1 /* Handle parameterized types (templates) for GNU C++. 2 Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 3 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011, 2012 4 Free Software Foundation, Inc. 5 Written by Ken Raeburn (raeburn@cygnus.com) while at Watchmaker Computing. 6 Rewritten by Jason Merrill (jason@cygnus.com). 7 8 This file is part of GCC. 9 10 GCC is free software; you can redistribute it and/or modify 11 it under the terms of the GNU General Public License as published by 12 the Free Software Foundation; either version 3, or (at your option) 13 any later version. 14 15 GCC is distributed in the hope that it will be useful, 16 but WITHOUT ANY WARRANTY; without even the implied warranty of 17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 18 GNU General Public License for more details. 19 20 You should have received a copy of the GNU General Public License 21 along with GCC; see the file COPYING3. If not see 22 <http://www.gnu.org/licenses/>. */ 23 24 /* Known bugs or deficiencies include: 25 26 all methods must be provided in header files; can't use a source 27 file that contains only the method templates and "just win". */ 28 29 #include "config.h" 30 #include "system.h" 31 #include "coretypes.h" 32 #include "tm.h" 33 #include "tree.h" 34 #include "intl.h" 35 #include "pointer-set.h" 36 #include "flags.h" 37 #include "cp-tree.h" 38 #include "c-family/c-common.h" 39 #include "c-family/c-objc.h" 40 #include "cp-objcp-common.h" 41 #include "tree-inline.h" 42 #include "decl.h" 43 #include "output.h" 44 #include "toplev.h" 45 #include "timevar.h" 46 #include "tree-iterator.h" 47 #include "vecprim.h" 48 49 /* The type of functions taking a tree, and some additional data, and 50 returning an int. */ 51 typedef int (*tree_fn_t) (tree, void*); 52 53 /* The PENDING_TEMPLATES is a TREE_LIST of templates whose 54 instantiations have been deferred, either because their definitions 55 were not yet available, or because we were putting off doing the work. */ 56 struct GTY ((chain_next ("%h.next"))) pending_template { 57 struct pending_template *next; 58 struct tinst_level *tinst; 59 }; 60 61 static GTY(()) struct pending_template *pending_templates; 62 static GTY(()) struct pending_template *last_pending_template; 63 64 int processing_template_parmlist; 65 static int template_header_count; 66 67 static GTY(()) tree saved_trees; 68 static VEC(int,heap) *inline_parm_levels; 69 70 static GTY(()) struct tinst_level *current_tinst_level; 71 72 static GTY(()) tree saved_access_scope; 73 74 /* Live only within one (recursive) call to tsubst_expr. We use 75 this to pass the statement expression node from the STMT_EXPR 76 to the EXPR_STMT that is its result. */ 77 static tree cur_stmt_expr; 78 79 /* A map from local variable declarations in the body of the template 80 presently being instantiated to the corresponding instantiated 81 local variables. */ 82 static htab_t local_specializations; 83 84 typedef struct GTY(()) spec_entry 85 { 86 tree tmpl; 87 tree args; 88 tree spec; 89 } spec_entry; 90 91 static GTY ((param_is (spec_entry))) 92 htab_t decl_specializations; 93 94 static GTY ((param_is (spec_entry))) 95 htab_t type_specializations; 96 97 /* Contains canonical template parameter types. The vector is indexed by 98 the TEMPLATE_TYPE_IDX of the template parameter. Each element is a 99 TREE_LIST, whose TREE_VALUEs contain the canonical template 100 parameters of various types and levels. */ 101 static GTY(()) VEC(tree,gc) *canonical_template_parms; 102 103 #define UNIFY_ALLOW_NONE 0 104 #define UNIFY_ALLOW_MORE_CV_QUAL 1 105 #define UNIFY_ALLOW_LESS_CV_QUAL 2 106 #define UNIFY_ALLOW_DERIVED 4 107 #define UNIFY_ALLOW_INTEGER 8 108 #define UNIFY_ALLOW_OUTER_LEVEL 16 109 #define UNIFY_ALLOW_OUTER_MORE_CV_QUAL 32 110 #define UNIFY_ALLOW_OUTER_LESS_CV_QUAL 64 111 112 enum template_base_result { 113 tbr_incomplete_type, 114 tbr_ambiguous_baseclass, 115 tbr_success 116 }; 117 118 static void push_access_scope (tree); 119 static void pop_access_scope (tree); 120 static void push_deduction_access_scope (tree); 121 static void pop_deduction_access_scope (tree); 122 static bool resolve_overloaded_unification (tree, tree, tree, tree, 123 unification_kind_t, int, 124 bool); 125 static int try_one_overload (tree, tree, tree, tree, tree, 126 unification_kind_t, int, bool, bool); 127 static int unify (tree, tree, tree, tree, int, bool); 128 static void add_pending_template (tree); 129 static tree reopen_tinst_level (struct tinst_level *); 130 static tree tsubst_initializer_list (tree, tree); 131 static tree get_class_bindings (tree, tree, tree); 132 static tree coerce_template_parms (tree, tree, tree, tsubst_flags_t, 133 bool, bool); 134 static void tsubst_enum (tree, tree, tree); 135 static tree add_to_template_args (tree, tree); 136 static tree add_outermost_template_args (tree, tree); 137 static bool check_instantiated_args (tree, tree, tsubst_flags_t); 138 static int maybe_adjust_types_for_deduction (unification_kind_t, tree*, tree*, 139 tree); 140 static int type_unification_real (tree, tree, tree, const tree *, 141 unsigned int, int, unification_kind_t, int, 142 bool); 143 static void note_template_header (int); 144 static tree convert_nontype_argument_function (tree, tree); 145 static tree convert_nontype_argument (tree, tree, tsubst_flags_t); 146 static tree convert_template_argument (tree, tree, tree, 147 tsubst_flags_t, int, tree); 148 static int for_each_template_parm (tree, tree_fn_t, void*, 149 struct pointer_set_t*, bool); 150 static tree expand_template_argument_pack (tree); 151 static tree build_template_parm_index (int, int, int, tree, tree); 152 static bool inline_needs_template_parms (tree); 153 static void push_inline_template_parms_recursive (tree, int); 154 static tree retrieve_local_specialization (tree); 155 static void register_local_specialization (tree, tree); 156 static hashval_t hash_specialization (const void *p); 157 static tree reduce_template_parm_level (tree, tree, int, tree, tsubst_flags_t); 158 static int mark_template_parm (tree, void *); 159 static int template_parm_this_level_p (tree, void *); 160 static tree tsubst_friend_function (tree, tree); 161 static tree tsubst_friend_class (tree, tree); 162 static int can_complete_type_without_circularity (tree); 163 static tree get_bindings (tree, tree, tree, bool); 164 static int template_decl_level (tree); 165 static int check_cv_quals_for_unify (int, tree, tree); 166 static void template_parm_level_and_index (tree, int*, int*); 167 static int unify_pack_expansion (tree, tree, tree, 168 tree, unification_kind_t, bool, bool); 169 static tree tsubst_template_arg (tree, tree, tsubst_flags_t, tree); 170 static tree tsubst_template_args (tree, tree, tsubst_flags_t, tree); 171 static tree tsubst_template_parms (tree, tree, tsubst_flags_t); 172 static void regenerate_decl_from_template (tree, tree); 173 static tree most_specialized_class (tree, tree, tsubst_flags_t); 174 static tree tsubst_aggr_type (tree, tree, tsubst_flags_t, tree, int); 175 static tree tsubst_arg_types (tree, tree, tree, tsubst_flags_t, tree); 176 static tree tsubst_function_type (tree, tree, tsubst_flags_t, tree); 177 static bool check_specialization_scope (void); 178 static tree process_partial_specialization (tree); 179 static void set_current_access_from_decl (tree); 180 static enum template_base_result get_template_base (tree, tree, tree, tree, 181 bool , tree *); 182 static tree try_class_unification (tree, tree, tree, tree, bool); 183 static int coerce_template_template_parms (tree, tree, tsubst_flags_t, 184 tree, tree); 185 static bool template_template_parm_bindings_ok_p (tree, tree); 186 static int template_args_equal (tree, tree); 187 static void tsubst_default_arguments (tree); 188 static tree for_each_template_parm_r (tree *, int *, void *); 189 static tree copy_default_args_to_explicit_spec_1 (tree, tree); 190 static void copy_default_args_to_explicit_spec (tree); 191 static int invalid_nontype_parm_type_p (tree, tsubst_flags_t); 192 static int eq_local_specializations (const void *, const void *); 193 static bool dependent_template_arg_p (tree); 194 static bool any_template_arguments_need_structural_equality_p (tree); 195 static bool dependent_type_p_r (tree); 196 static tree tsubst_expr (tree, tree, tsubst_flags_t, tree, bool); 197 static tree tsubst_copy (tree, tree, tsubst_flags_t, tree); 198 static tree tsubst_pack_expansion (tree, tree, tsubst_flags_t, tree); 199 static tree tsubst_decl (tree, tree, tsubst_flags_t); 200 static void perform_typedefs_access_check (tree tmpl, tree targs); 201 static void append_type_to_template_for_access_check_1 (tree, tree, tree, 202 location_t); 203 static tree listify (tree); 204 static tree listify_autos (tree, tree); 205 static tree template_parm_to_arg (tree t); 206 static bool arg_from_parm_pack_p (tree, tree); 207 static tree current_template_args (void); 208 static tree tsubst_template_parm (tree, tree, tsubst_flags_t); 209 210 /* Make the current scope suitable for access checking when we are 211 processing T. T can be FUNCTION_DECL for instantiated function 212 template, or VAR_DECL for static member variable (need by 213 instantiate_decl). */ 214 215 static void 216 push_access_scope (tree t) 217 { 218 gcc_assert (TREE_CODE (t) == FUNCTION_DECL 219 || TREE_CODE (t) == VAR_DECL); 220 221 if (DECL_FRIEND_CONTEXT (t)) 222 push_nested_class (DECL_FRIEND_CONTEXT (t)); 223 else if (DECL_CLASS_SCOPE_P (t)) 224 push_nested_class (DECL_CONTEXT (t)); 225 else 226 push_to_top_level (); 227 228 if (TREE_CODE (t) == FUNCTION_DECL) 229 { 230 saved_access_scope = tree_cons 231 (NULL_TREE, current_function_decl, saved_access_scope); 232 current_function_decl = t; 233 } 234 } 235 236 /* Restore the scope set up by push_access_scope. T is the node we 237 are processing. */ 238 239 static void 240 pop_access_scope (tree t) 241 { 242 if (TREE_CODE (t) == FUNCTION_DECL) 243 { 244 current_function_decl = TREE_VALUE (saved_access_scope); 245 saved_access_scope = TREE_CHAIN (saved_access_scope); 246 } 247 248 if (DECL_FRIEND_CONTEXT (t) || DECL_CLASS_SCOPE_P (t)) 249 pop_nested_class (); 250 else 251 pop_from_top_level (); 252 } 253 254 /* Do any processing required when DECL (a member template 255 declaration) is finished. Returns the TEMPLATE_DECL corresponding 256 to DECL, unless it is a specialization, in which case the DECL 257 itself is returned. */ 258 259 tree 260 finish_member_template_decl (tree decl) 261 { 262 if (decl == error_mark_node) 263 return error_mark_node; 264 265 gcc_assert (DECL_P (decl)); 266 267 if (TREE_CODE (decl) == TYPE_DECL) 268 { 269 tree type; 270 271 type = TREE_TYPE (decl); 272 if (type == error_mark_node) 273 return error_mark_node; 274 if (MAYBE_CLASS_TYPE_P (type) 275 && CLASSTYPE_TEMPLATE_INFO (type) 276 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (type)) 277 { 278 tree tmpl = CLASSTYPE_TI_TEMPLATE (type); 279 check_member_template (tmpl); 280 return tmpl; 281 } 282 return NULL_TREE; 283 } 284 else if (TREE_CODE (decl) == FIELD_DECL) 285 error ("data member %qD cannot be a member template", decl); 286 else if (DECL_TEMPLATE_INFO (decl)) 287 { 288 if (!DECL_TEMPLATE_SPECIALIZATION (decl)) 289 { 290 check_member_template (DECL_TI_TEMPLATE (decl)); 291 return DECL_TI_TEMPLATE (decl); 292 } 293 else 294 return decl; 295 } 296 else 297 error ("invalid member template declaration %qD", decl); 298 299 return error_mark_node; 300 } 301 302 /* Create a template info node. */ 303 304 tree 305 build_template_info (tree template_decl, tree template_args) 306 { 307 tree result = make_node (TEMPLATE_INFO); 308 TI_TEMPLATE (result) = template_decl; 309 TI_ARGS (result) = template_args; 310 return result; 311 } 312 313 /* Return the template info node corresponding to T, whatever T is. */ 314 315 tree 316 get_template_info (const_tree t) 317 { 318 tree tinfo = NULL_TREE; 319 320 if (!t || t == error_mark_node) 321 return NULL; 322 323 if (DECL_P (t) && DECL_LANG_SPECIFIC (t)) 324 tinfo = DECL_TEMPLATE_INFO (t); 325 326 if (!tinfo && DECL_IMPLICIT_TYPEDEF_P (t)) 327 t = TREE_TYPE (t); 328 329 if (TAGGED_TYPE_P (t)) 330 tinfo = TYPE_TEMPLATE_INFO (t); 331 else if (TREE_CODE (t) == BOUND_TEMPLATE_TEMPLATE_PARM) 332 tinfo = TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t); 333 334 return tinfo; 335 } 336 337 /* Returns the template nesting level of the indicated class TYPE. 338 339 For example, in: 340 template <class T> 341 struct A 342 { 343 template <class U> 344 struct B {}; 345 }; 346 347 A<T>::B<U> has depth two, while A<T> has depth one. 348 Both A<T>::B<int> and A<int>::B<U> have depth one, if 349 they are instantiations, not specializations. 350 351 This function is guaranteed to return 0 if passed NULL_TREE so 352 that, for example, `template_class_depth (current_class_type)' is 353 always safe. */ 354 355 int 356 template_class_depth (tree type) 357 { 358 int depth; 359 360 for (depth = 0; 361 type && TREE_CODE (type) != NAMESPACE_DECL; 362 type = (TREE_CODE (type) == FUNCTION_DECL) 363 ? CP_DECL_CONTEXT (type) : CP_TYPE_CONTEXT (type)) 364 { 365 tree tinfo = get_template_info (type); 366 367 if (tinfo && PRIMARY_TEMPLATE_P (TI_TEMPLATE (tinfo)) 368 && uses_template_parms (INNERMOST_TEMPLATE_ARGS (TI_ARGS (tinfo)))) 369 ++depth; 370 } 371 372 return depth; 373 } 374 375 /* Subroutine of maybe_begin_member_template_processing. 376 Returns true if processing DECL needs us to push template parms. */ 377 378 static bool 379 inline_needs_template_parms (tree decl) 380 { 381 if (! DECL_TEMPLATE_INFO (decl)) 382 return false; 383 384 return (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (most_general_template (decl))) 385 > (processing_template_decl + DECL_TEMPLATE_SPECIALIZATION (decl))); 386 } 387 388 /* Subroutine of maybe_begin_member_template_processing. 389 Push the template parms in PARMS, starting from LEVELS steps into the 390 chain, and ending at the beginning, since template parms are listed 391 innermost first. */ 392 393 static void 394 push_inline_template_parms_recursive (tree parmlist, int levels) 395 { 396 tree parms = TREE_VALUE (parmlist); 397 int i; 398 399 if (levels > 1) 400 push_inline_template_parms_recursive (TREE_CHAIN (parmlist), levels - 1); 401 402 ++processing_template_decl; 403 current_template_parms 404 = tree_cons (size_int (processing_template_decl), 405 parms, current_template_parms); 406 TEMPLATE_PARMS_FOR_INLINE (current_template_parms) = 1; 407 408 begin_scope (TREE_VEC_LENGTH (parms) ? sk_template_parms : sk_template_spec, 409 NULL); 410 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i) 411 { 412 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i)); 413 414 if (parm == error_mark_node) 415 continue; 416 417 gcc_assert (DECL_P (parm)); 418 419 switch (TREE_CODE (parm)) 420 { 421 case TYPE_DECL: 422 case TEMPLATE_DECL: 423 pushdecl (parm); 424 break; 425 426 case PARM_DECL: 427 { 428 /* Make a CONST_DECL as is done in process_template_parm. 429 It is ugly that we recreate this here; the original 430 version built in process_template_parm is no longer 431 available. */ 432 tree decl = build_decl (DECL_SOURCE_LOCATION (parm), 433 CONST_DECL, DECL_NAME (parm), 434 TREE_TYPE (parm)); 435 DECL_ARTIFICIAL (decl) = 1; 436 TREE_CONSTANT (decl) = 1; 437 TREE_READONLY (decl) = 1; 438 DECL_INITIAL (decl) = DECL_INITIAL (parm); 439 SET_DECL_TEMPLATE_PARM_P (decl); 440 pushdecl (decl); 441 } 442 break; 443 444 default: 445 gcc_unreachable (); 446 } 447 } 448 } 449 450 /* Restore the template parameter context for a member template or 451 a friend template defined in a class definition. */ 452 453 void 454 maybe_begin_member_template_processing (tree decl) 455 { 456 tree parms; 457 int levels = 0; 458 459 if (inline_needs_template_parms (decl)) 460 { 461 parms = DECL_TEMPLATE_PARMS (most_general_template (decl)); 462 levels = TMPL_PARMS_DEPTH (parms) - processing_template_decl; 463 464 if (DECL_TEMPLATE_SPECIALIZATION (decl)) 465 { 466 --levels; 467 parms = TREE_CHAIN (parms); 468 } 469 470 push_inline_template_parms_recursive (parms, levels); 471 } 472 473 /* Remember how many levels of template parameters we pushed so that 474 we can pop them later. */ 475 VEC_safe_push (int, heap, inline_parm_levels, levels); 476 } 477 478 /* Undo the effects of maybe_begin_member_template_processing. */ 479 480 void 481 maybe_end_member_template_processing (void) 482 { 483 int i; 484 int last; 485 486 if (VEC_length (int, inline_parm_levels) == 0) 487 return; 488 489 last = VEC_pop (int, inline_parm_levels); 490 for (i = 0; i < last; ++i) 491 { 492 --processing_template_decl; 493 current_template_parms = TREE_CHAIN (current_template_parms); 494 poplevel (0, 0, 0); 495 } 496 } 497 498 /* Return a new template argument vector which contains all of ARGS, 499 but has as its innermost set of arguments the EXTRA_ARGS. */ 500 501 static tree 502 add_to_template_args (tree args, tree extra_args) 503 { 504 tree new_args; 505 int extra_depth; 506 int i; 507 int j; 508 509 if (args == NULL_TREE || extra_args == error_mark_node) 510 return extra_args; 511 512 extra_depth = TMPL_ARGS_DEPTH (extra_args); 513 new_args = make_tree_vec (TMPL_ARGS_DEPTH (args) + extra_depth); 514 515 for (i = 1; i <= TMPL_ARGS_DEPTH (args); ++i) 516 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (args, i)); 517 518 for (j = 1; j <= extra_depth; ++j, ++i) 519 SET_TMPL_ARGS_LEVEL (new_args, i, TMPL_ARGS_LEVEL (extra_args, j)); 520 521 return new_args; 522 } 523 524 /* Like add_to_template_args, but only the outermost ARGS are added to 525 the EXTRA_ARGS. In particular, all but TMPL_ARGS_DEPTH 526 (EXTRA_ARGS) levels are added. This function is used to combine 527 the template arguments from a partial instantiation with the 528 template arguments used to attain the full instantiation from the 529 partial instantiation. */ 530 531 static tree 532 add_outermost_template_args (tree args, tree extra_args) 533 { 534 tree new_args; 535 536 /* If there are more levels of EXTRA_ARGS than there are ARGS, 537 something very fishy is going on. */ 538 gcc_assert (TMPL_ARGS_DEPTH (args) >= TMPL_ARGS_DEPTH (extra_args)); 539 540 /* If *all* the new arguments will be the EXTRA_ARGS, just return 541 them. */ 542 if (TMPL_ARGS_DEPTH (args) == TMPL_ARGS_DEPTH (extra_args)) 543 return extra_args; 544 545 /* For the moment, we make ARGS look like it contains fewer levels. */ 546 TREE_VEC_LENGTH (args) -= TMPL_ARGS_DEPTH (extra_args); 547 548 new_args = add_to_template_args (args, extra_args); 549 550 /* Now, we restore ARGS to its full dimensions. */ 551 TREE_VEC_LENGTH (args) += TMPL_ARGS_DEPTH (extra_args); 552 553 return new_args; 554 } 555 556 /* Return the N levels of innermost template arguments from the ARGS. */ 557 558 tree 559 get_innermost_template_args (tree args, int n) 560 { 561 tree new_args; 562 int extra_levels; 563 int i; 564 565 gcc_assert (n >= 0); 566 567 /* If N is 1, just return the innermost set of template arguments. */ 568 if (n == 1) 569 return TMPL_ARGS_LEVEL (args, TMPL_ARGS_DEPTH (args)); 570 571 /* If we're not removing anything, just return the arguments we were 572 given. */ 573 extra_levels = TMPL_ARGS_DEPTH (args) - n; 574 gcc_assert (extra_levels >= 0); 575 if (extra_levels == 0) 576 return args; 577 578 /* Make a new set of arguments, not containing the outer arguments. */ 579 new_args = make_tree_vec (n); 580 for (i = 1; i <= n; ++i) 581 SET_TMPL_ARGS_LEVEL (new_args, i, 582 TMPL_ARGS_LEVEL (args, i + extra_levels)); 583 584 return new_args; 585 } 586 587 /* The inverse of get_innermost_template_args: Return all but the innermost 588 EXTRA_LEVELS levels of template arguments from the ARGS. */ 589 590 static tree 591 strip_innermost_template_args (tree args, int extra_levels) 592 { 593 tree new_args; 594 int n = TMPL_ARGS_DEPTH (args) - extra_levels; 595 int i; 596 597 gcc_assert (n >= 0); 598 599 /* If N is 1, just return the outermost set of template arguments. */ 600 if (n == 1) 601 return TMPL_ARGS_LEVEL (args, 1); 602 603 /* If we're not removing anything, just return the arguments we were 604 given. */ 605 gcc_assert (extra_levels >= 0); 606 if (extra_levels == 0) 607 return args; 608 609 /* Make a new set of arguments, not containing the inner arguments. */ 610 new_args = make_tree_vec (n); 611 for (i = 1; i <= n; ++i) 612 SET_TMPL_ARGS_LEVEL (new_args, i, 613 TMPL_ARGS_LEVEL (args, i)); 614 615 return new_args; 616 } 617 618 /* We've got a template header coming up; push to a new level for storing 619 the parms. */ 620 621 void 622 begin_template_parm_list (void) 623 { 624 /* We use a non-tag-transparent scope here, which causes pushtag to 625 put tags in this scope, rather than in the enclosing class or 626 namespace scope. This is the right thing, since we want 627 TEMPLATE_DECLS, and not TYPE_DECLS for template classes. For a 628 global template class, push_template_decl handles putting the 629 TEMPLATE_DECL into top-level scope. For a nested template class, 630 e.g.: 631 632 template <class T> struct S1 { 633 template <class T> struct S2 {}; 634 }; 635 636 pushtag contains special code to call pushdecl_with_scope on the 637 TEMPLATE_DECL for S2. */ 638 begin_scope (sk_template_parms, NULL); 639 ++processing_template_decl; 640 ++processing_template_parmlist; 641 note_template_header (0); 642 } 643 644 /* This routine is called when a specialization is declared. If it is 645 invalid to declare a specialization here, an error is reported and 646 false is returned, otherwise this routine will return true. */ 647 648 static bool 649 check_specialization_scope (void) 650 { 651 tree scope = current_scope (); 652 653 /* [temp.expl.spec] 654 655 An explicit specialization shall be declared in the namespace of 656 which the template is a member, or, for member templates, in the 657 namespace of which the enclosing class or enclosing class 658 template is a member. An explicit specialization of a member 659 function, member class or static data member of a class template 660 shall be declared in the namespace of which the class template 661 is a member. */ 662 if (scope && TREE_CODE (scope) != NAMESPACE_DECL) 663 { 664 error ("explicit specialization in non-namespace scope %qD", scope); 665 return false; 666 } 667 668 /* [temp.expl.spec] 669 670 In an explicit specialization declaration for a member of a class 671 template or a member template that appears in namespace scope, 672 the member template and some of its enclosing class templates may 673 remain unspecialized, except that the declaration shall not 674 explicitly specialize a class member template if its enclosing 675 class templates are not explicitly specialized as well. */ 676 if (current_template_parms) 677 { 678 error ("enclosing class templates are not explicitly specialized"); 679 return false; 680 } 681 682 return true; 683 } 684 685 /* We've just seen template <>. */ 686 687 bool 688 begin_specialization (void) 689 { 690 begin_scope (sk_template_spec, NULL); 691 note_template_header (1); 692 return check_specialization_scope (); 693 } 694 695 /* Called at then end of processing a declaration preceded by 696 template<>. */ 697 698 void 699 end_specialization (void) 700 { 701 finish_scope (); 702 reset_specialization (); 703 } 704 705 /* Any template <>'s that we have seen thus far are not referring to a 706 function specialization. */ 707 708 void 709 reset_specialization (void) 710 { 711 processing_specialization = 0; 712 template_header_count = 0; 713 } 714 715 /* We've just seen a template header. If SPECIALIZATION is nonzero, 716 it was of the form template <>. */ 717 718 static void 719 note_template_header (int specialization) 720 { 721 processing_specialization = specialization; 722 template_header_count++; 723 } 724 725 /* We're beginning an explicit instantiation. */ 726 727 void 728 begin_explicit_instantiation (void) 729 { 730 gcc_assert (!processing_explicit_instantiation); 731 processing_explicit_instantiation = true; 732 } 733 734 735 void 736 end_explicit_instantiation (void) 737 { 738 gcc_assert (processing_explicit_instantiation); 739 processing_explicit_instantiation = false; 740 } 741 742 /* An explicit specialization or partial specialization TMPL is being 743 declared. Check that the namespace in which the specialization is 744 occurring is permissible. Returns false iff it is invalid to 745 specialize TMPL in the current namespace. */ 746 747 static bool 748 check_specialization_namespace (tree tmpl) 749 { 750 tree tpl_ns = decl_namespace_context (tmpl); 751 752 /* [tmpl.expl.spec] 753 754 An explicit specialization shall be declared in the namespace of 755 which the template is a member, or, for member templates, in the 756 namespace of which the enclosing class or enclosing class 757 template is a member. An explicit specialization of a member 758 function, member class or static data member of a class template 759 shall be declared in the namespace of which the class template is 760 a member. */ 761 if (current_scope() != DECL_CONTEXT (tmpl) 762 && !at_namespace_scope_p ()) 763 { 764 error ("specialization of %qD must appear at namespace scope", tmpl); 765 return false; 766 } 767 if (is_associated_namespace (current_namespace, tpl_ns)) 768 /* Same or super-using namespace. */ 769 return true; 770 else 771 { 772 permerror (input_location, "specialization of %qD in different namespace", tmpl); 773 permerror (input_location, " from definition of %q+#D", tmpl); 774 return false; 775 } 776 } 777 778 /* SPEC is an explicit instantiation. Check that it is valid to 779 perform this explicit instantiation in the current namespace. */ 780 781 static void 782 check_explicit_instantiation_namespace (tree spec) 783 { 784 tree ns; 785 786 /* DR 275: An explicit instantiation shall appear in an enclosing 787 namespace of its template. */ 788 ns = decl_namespace_context (spec); 789 if (!is_ancestor (current_namespace, ns)) 790 permerror (input_location, "explicit instantiation of %qD in namespace %qD " 791 "(which does not enclose namespace %qD)", 792 spec, current_namespace, ns); 793 } 794 795 /* The TYPE is being declared. If it is a template type, that means it 796 is a partial specialization. Do appropriate error-checking. */ 797 798 tree 799 maybe_process_partial_specialization (tree type) 800 { 801 tree context; 802 803 if (type == error_mark_node) 804 return error_mark_node; 805 806 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM) 807 { 808 error ("name of class shadows template template parameter %qD", 809 TYPE_NAME (type)); 810 return error_mark_node; 811 } 812 813 context = TYPE_CONTEXT (type); 814 815 if ((CLASS_TYPE_P (type) && CLASSTYPE_USE_TEMPLATE (type)) 816 /* Consider non-class instantiations of alias templates as 817 well. */ 818 || (TYPE_P (type) 819 && TYPE_TEMPLATE_INFO (type) 820 && DECL_LANG_SPECIFIC (TYPE_NAME (type)) 821 && DECL_USE_TEMPLATE (TYPE_NAME (type)))) 822 { 823 /* This is for ordinary explicit specialization and partial 824 specialization of a template class such as: 825 826 template <> class C<int>; 827 828 or: 829 830 template <class T> class C<T*>; 831 832 Make sure that `C<int>' and `C<T*>' are implicit instantiations. */ 833 834 if (CLASS_TYPE_P (type) 835 && CLASSTYPE_IMPLICIT_INSTANTIATION (type) 836 && !COMPLETE_TYPE_P (type)) 837 { 838 check_specialization_namespace (CLASSTYPE_TI_TEMPLATE (type)); 839 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type); 840 if (processing_template_decl) 841 { 842 if (push_template_decl (TYPE_MAIN_DECL (type)) 843 == error_mark_node) 844 return error_mark_node; 845 } 846 } 847 else if (CLASS_TYPE_P (type) 848 && CLASSTYPE_TEMPLATE_INSTANTIATION (type)) 849 error ("specialization of %qT after instantiation", type); 850 851 if (DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (type))) 852 { 853 error ("partial specialization of alias template %qD", 854 TYPE_TI_TEMPLATE (type)); 855 return error_mark_node; 856 } 857 } 858 else if (CLASS_TYPE_P (type) 859 && !CLASSTYPE_USE_TEMPLATE (type) 860 && CLASSTYPE_TEMPLATE_INFO (type) 861 && context && CLASS_TYPE_P (context) 862 && CLASSTYPE_TEMPLATE_INFO (context)) 863 { 864 /* This is for an explicit specialization of member class 865 template according to [temp.expl.spec/18]: 866 867 template <> template <class U> class C<int>::D; 868 869 The context `C<int>' must be an implicit instantiation. 870 Otherwise this is just a member class template declared 871 earlier like: 872 873 template <> class C<int> { template <class U> class D; }; 874 template <> template <class U> class C<int>::D; 875 876 In the first case, `C<int>::D' is a specialization of `C<T>::D' 877 while in the second case, `C<int>::D' is a primary template 878 and `C<T>::D' may not exist. */ 879 880 if (CLASSTYPE_IMPLICIT_INSTANTIATION (context) 881 && !COMPLETE_TYPE_P (type)) 882 { 883 tree t; 884 tree tmpl = CLASSTYPE_TI_TEMPLATE (type); 885 886 if (current_namespace 887 != decl_namespace_context (tmpl)) 888 { 889 permerror (input_location, "specializing %q#T in different namespace", type); 890 permerror (input_location, " from definition of %q+#D", tmpl); 891 } 892 893 /* Check for invalid specialization after instantiation: 894 895 template <> template <> class C<int>::D<int>; 896 template <> template <class U> class C<int>::D; */ 897 898 for (t = DECL_TEMPLATE_INSTANTIATIONS (tmpl); 899 t; t = TREE_CHAIN (t)) 900 { 901 tree inst = TREE_VALUE (t); 902 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (inst)) 903 { 904 /* We already have a full specialization of this partial 905 instantiation. Reassign it to the new member 906 specialization template. */ 907 spec_entry elt; 908 spec_entry *entry; 909 void **slot; 910 911 elt.tmpl = most_general_template (tmpl); 912 elt.args = CLASSTYPE_TI_ARGS (inst); 913 elt.spec = inst; 914 915 htab_remove_elt (type_specializations, &elt); 916 917 elt.tmpl = tmpl; 918 elt.args = INNERMOST_TEMPLATE_ARGS (elt.args); 919 920 slot = htab_find_slot (type_specializations, &elt, INSERT); 921 entry = ggc_alloc_spec_entry (); 922 *entry = elt; 923 *slot = entry; 924 } 925 else if (COMPLETE_OR_OPEN_TYPE_P (inst)) 926 /* But if we've had an implicit instantiation, that's a 927 problem ([temp.expl.spec]/6). */ 928 error ("specialization %qT after instantiation %qT", 929 type, inst); 930 } 931 932 /* Mark TYPE as a specialization. And as a result, we only 933 have one level of template argument for the innermost 934 class template. */ 935 SET_CLASSTYPE_TEMPLATE_SPECIALIZATION (type); 936 CLASSTYPE_TI_ARGS (type) 937 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)); 938 } 939 } 940 else if (processing_specialization) 941 { 942 /* Someday C++0x may allow for enum template specialization. */ 943 if (cxx_dialect > cxx98 && TREE_CODE (type) == ENUMERAL_TYPE 944 && CLASS_TYPE_P (context) && CLASSTYPE_USE_TEMPLATE (context)) 945 pedwarn (input_location, OPT_pedantic, "template specialization " 946 "of %qD not allowed by ISO C++", type); 947 else 948 { 949 error ("explicit specialization of non-template %qT", type); 950 return error_mark_node; 951 } 952 } 953 954 return type; 955 } 956 957 /* Returns nonzero if we can optimize the retrieval of specializations 958 for TMPL, a TEMPLATE_DECL. In particular, for such a template, we 959 do not use DECL_TEMPLATE_SPECIALIZATIONS at all. */ 960 961 static inline bool 962 optimize_specialization_lookup_p (tree tmpl) 963 { 964 return (DECL_FUNCTION_TEMPLATE_P (tmpl) 965 && DECL_CLASS_SCOPE_P (tmpl) 966 /* DECL_CLASS_SCOPE_P holds of T::f even if T is a template 967 parameter. */ 968 && CLASS_TYPE_P (DECL_CONTEXT (tmpl)) 969 /* The optimized lookup depends on the fact that the 970 template arguments for the member function template apply 971 purely to the containing class, which is not true if the 972 containing class is an explicit or partial 973 specialization. */ 974 && !CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (tmpl)) 975 && !DECL_MEMBER_TEMPLATE_P (tmpl) 976 && !DECL_CONV_FN_P (tmpl) 977 /* It is possible to have a template that is not a member 978 template and is not a member of a template class: 979 980 template <typename T> 981 struct S { friend A::f(); }; 982 983 Here, the friend function is a template, but the context does 984 not have template information. The optimized lookup relies 985 on having ARGS be the template arguments for both the class 986 and the function template. */ 987 && !DECL_FRIEND_P (DECL_TEMPLATE_RESULT (tmpl))); 988 } 989 990 /* Retrieve the specialization (in the sense of [temp.spec] - a 991 specialization is either an instantiation or an explicit 992 specialization) of TMPL for the given template ARGS. If there is 993 no such specialization, return NULL_TREE. The ARGS are a vector of 994 arguments, or a vector of vectors of arguments, in the case of 995 templates with more than one level of parameters. 996 997 If TMPL is a type template and CLASS_SPECIALIZATIONS_P is true, 998 then we search for a partial specialization matching ARGS. This 999 parameter is ignored if TMPL is not a class template. */ 1000 1001 static tree 1002 retrieve_specialization (tree tmpl, tree args, hashval_t hash) 1003 { 1004 if (args == error_mark_node) 1005 return NULL_TREE; 1006 1007 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL); 1008 1009 /* There should be as many levels of arguments as there are 1010 levels of parameters. */ 1011 gcc_assert (TMPL_ARGS_DEPTH (args) 1012 == TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl))); 1013 1014 if (optimize_specialization_lookup_p (tmpl)) 1015 { 1016 tree class_template; 1017 tree class_specialization; 1018 VEC(tree,gc) *methods; 1019 tree fns; 1020 int idx; 1021 1022 /* The template arguments actually apply to the containing 1023 class. Find the class specialization with those 1024 arguments. */ 1025 class_template = CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (tmpl)); 1026 class_specialization 1027 = retrieve_specialization (class_template, args, 0); 1028 if (!class_specialization) 1029 return NULL_TREE; 1030 /* Now, find the appropriate entry in the CLASSTYPE_METHOD_VEC 1031 for the specialization. */ 1032 idx = class_method_index_for_fn (class_specialization, tmpl); 1033 if (idx == -1) 1034 return NULL_TREE; 1035 /* Iterate through the methods with the indicated name, looking 1036 for the one that has an instance of TMPL. */ 1037 methods = CLASSTYPE_METHOD_VEC (class_specialization); 1038 for (fns = VEC_index (tree, methods, idx); fns; fns = OVL_NEXT (fns)) 1039 { 1040 tree fn = OVL_CURRENT (fns); 1041 if (DECL_TEMPLATE_INFO (fn) && DECL_TI_TEMPLATE (fn) == tmpl 1042 /* using-declarations can add base methods to the method vec, 1043 and we don't want those here. */ 1044 && DECL_CONTEXT (fn) == class_specialization) 1045 return fn; 1046 } 1047 return NULL_TREE; 1048 } 1049 else 1050 { 1051 spec_entry *found; 1052 spec_entry elt; 1053 htab_t specializations; 1054 1055 elt.tmpl = tmpl; 1056 elt.args = args; 1057 elt.spec = NULL_TREE; 1058 1059 if (DECL_CLASS_TEMPLATE_P (tmpl)) 1060 specializations = type_specializations; 1061 else 1062 specializations = decl_specializations; 1063 1064 if (hash == 0) 1065 hash = hash_specialization (&elt); 1066 found = (spec_entry *) htab_find_with_hash (specializations, &elt, hash); 1067 if (found) 1068 return found->spec; 1069 } 1070 1071 return NULL_TREE; 1072 } 1073 1074 /* Like retrieve_specialization, but for local declarations. */ 1075 1076 static tree 1077 retrieve_local_specialization (tree tmpl) 1078 { 1079 tree spec; 1080 1081 if (local_specializations == NULL) 1082 return NULL_TREE; 1083 1084 spec = (tree) htab_find_with_hash (local_specializations, tmpl, 1085 htab_hash_pointer (tmpl)); 1086 return spec ? TREE_PURPOSE (spec) : NULL_TREE; 1087 } 1088 1089 /* Returns nonzero iff DECL is a specialization of TMPL. */ 1090 1091 int 1092 is_specialization_of (tree decl, tree tmpl) 1093 { 1094 tree t; 1095 1096 if (TREE_CODE (decl) == FUNCTION_DECL) 1097 { 1098 for (t = decl; 1099 t != NULL_TREE; 1100 t = DECL_TEMPLATE_INFO (t) ? DECL_TI_TEMPLATE (t) : NULL_TREE) 1101 if (t == tmpl) 1102 return 1; 1103 } 1104 else 1105 { 1106 gcc_assert (TREE_CODE (decl) == TYPE_DECL); 1107 1108 for (t = TREE_TYPE (decl); 1109 t != NULL_TREE; 1110 t = CLASSTYPE_USE_TEMPLATE (t) 1111 ? TREE_TYPE (CLASSTYPE_TI_TEMPLATE (t)) : NULL_TREE) 1112 if (same_type_ignoring_top_level_qualifiers_p (t, TREE_TYPE (tmpl))) 1113 return 1; 1114 } 1115 1116 return 0; 1117 } 1118 1119 /* Returns nonzero iff DECL is a specialization of friend declaration 1120 FRIEND_DECL according to [temp.friend]. */ 1121 1122 bool 1123 is_specialization_of_friend (tree decl, tree friend_decl) 1124 { 1125 bool need_template = true; 1126 int template_depth; 1127 1128 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL 1129 || TREE_CODE (decl) == TYPE_DECL); 1130 1131 /* For [temp.friend/6] when FRIEND_DECL is an ordinary member function 1132 of a template class, we want to check if DECL is a specialization 1133 if this. */ 1134 if (TREE_CODE (friend_decl) == FUNCTION_DECL 1135 && DECL_TEMPLATE_INFO (friend_decl) 1136 && !DECL_USE_TEMPLATE (friend_decl)) 1137 { 1138 /* We want a TEMPLATE_DECL for `is_specialization_of'. */ 1139 friend_decl = DECL_TI_TEMPLATE (friend_decl); 1140 need_template = false; 1141 } 1142 else if (TREE_CODE (friend_decl) == TEMPLATE_DECL 1143 && !PRIMARY_TEMPLATE_P (friend_decl)) 1144 need_template = false; 1145 1146 /* There is nothing to do if this is not a template friend. */ 1147 if (TREE_CODE (friend_decl) != TEMPLATE_DECL) 1148 return false; 1149 1150 if (is_specialization_of (decl, friend_decl)) 1151 return true; 1152 1153 /* [temp.friend/6] 1154 A member of a class template may be declared to be a friend of a 1155 non-template class. In this case, the corresponding member of 1156 every specialization of the class template is a friend of the 1157 class granting friendship. 1158 1159 For example, given a template friend declaration 1160 1161 template <class T> friend void A<T>::f(); 1162 1163 the member function below is considered a friend 1164 1165 template <> struct A<int> { 1166 void f(); 1167 }; 1168 1169 For this type of template friend, TEMPLATE_DEPTH below will be 1170 nonzero. To determine if DECL is a friend of FRIEND, we first 1171 check if the enclosing class is a specialization of another. */ 1172 1173 template_depth = template_class_depth (CP_DECL_CONTEXT (friend_decl)); 1174 if (template_depth 1175 && DECL_CLASS_SCOPE_P (decl) 1176 && is_specialization_of (TYPE_NAME (DECL_CONTEXT (decl)), 1177 CLASSTYPE_TI_TEMPLATE (DECL_CONTEXT (friend_decl)))) 1178 { 1179 /* Next, we check the members themselves. In order to handle 1180 a few tricky cases, such as when FRIEND_DECL's are 1181 1182 template <class T> friend void A<T>::g(T t); 1183 template <class T> template <T t> friend void A<T>::h(); 1184 1185 and DECL's are 1186 1187 void A<int>::g(int); 1188 template <int> void A<int>::h(); 1189 1190 we need to figure out ARGS, the template arguments from 1191 the context of DECL. This is required for template substitution 1192 of `T' in the function parameter of `g' and template parameter 1193 of `h' in the above examples. Here ARGS corresponds to `int'. */ 1194 1195 tree context = DECL_CONTEXT (decl); 1196 tree args = NULL_TREE; 1197 int current_depth = 0; 1198 1199 while (current_depth < template_depth) 1200 { 1201 if (CLASSTYPE_TEMPLATE_INFO (context)) 1202 { 1203 if (current_depth == 0) 1204 args = TYPE_TI_ARGS (context); 1205 else 1206 args = add_to_template_args (TYPE_TI_ARGS (context), args); 1207 current_depth++; 1208 } 1209 context = TYPE_CONTEXT (context); 1210 } 1211 1212 if (TREE_CODE (decl) == FUNCTION_DECL) 1213 { 1214 bool is_template; 1215 tree friend_type; 1216 tree decl_type; 1217 tree friend_args_type; 1218 tree decl_args_type; 1219 1220 /* Make sure that both DECL and FRIEND_DECL are templates or 1221 non-templates. */ 1222 is_template = DECL_TEMPLATE_INFO (decl) 1223 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl)); 1224 if (need_template ^ is_template) 1225 return false; 1226 else if (is_template) 1227 { 1228 /* If both are templates, check template parameter list. */ 1229 tree friend_parms 1230 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl), 1231 args, tf_none); 1232 if (!comp_template_parms 1233 (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (decl)), 1234 friend_parms)) 1235 return false; 1236 1237 decl_type = TREE_TYPE (DECL_TI_TEMPLATE (decl)); 1238 } 1239 else 1240 decl_type = TREE_TYPE (decl); 1241 1242 friend_type = tsubst_function_type (TREE_TYPE (friend_decl), args, 1243 tf_none, NULL_TREE); 1244 if (friend_type == error_mark_node) 1245 return false; 1246 1247 /* Check if return types match. */ 1248 if (!same_type_p (TREE_TYPE (decl_type), TREE_TYPE (friend_type))) 1249 return false; 1250 1251 /* Check if function parameter types match, ignoring the 1252 `this' parameter. */ 1253 friend_args_type = TYPE_ARG_TYPES (friend_type); 1254 decl_args_type = TYPE_ARG_TYPES (decl_type); 1255 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (friend_decl)) 1256 friend_args_type = TREE_CHAIN (friend_args_type); 1257 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)) 1258 decl_args_type = TREE_CHAIN (decl_args_type); 1259 1260 return compparms (decl_args_type, friend_args_type); 1261 } 1262 else 1263 { 1264 /* DECL is a TYPE_DECL */ 1265 bool is_template; 1266 tree decl_type = TREE_TYPE (decl); 1267 1268 /* Make sure that both DECL and FRIEND_DECL are templates or 1269 non-templates. */ 1270 is_template 1271 = CLASSTYPE_TEMPLATE_INFO (decl_type) 1272 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (decl_type)); 1273 1274 if (need_template ^ is_template) 1275 return false; 1276 else if (is_template) 1277 { 1278 tree friend_parms; 1279 /* If both are templates, check the name of the two 1280 TEMPLATE_DECL's first because is_friend didn't. */ 1281 if (DECL_NAME (CLASSTYPE_TI_TEMPLATE (decl_type)) 1282 != DECL_NAME (friend_decl)) 1283 return false; 1284 1285 /* Now check template parameter list. */ 1286 friend_parms 1287 = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_decl), 1288 args, tf_none); 1289 return comp_template_parms 1290 (DECL_TEMPLATE_PARMS (CLASSTYPE_TI_TEMPLATE (decl_type)), 1291 friend_parms); 1292 } 1293 else 1294 return (DECL_NAME (decl) 1295 == DECL_NAME (friend_decl)); 1296 } 1297 } 1298 return false; 1299 } 1300 1301 /* Register the specialization SPEC as a specialization of TMPL with 1302 the indicated ARGS. IS_FRIEND indicates whether the specialization 1303 is actually just a friend declaration. Returns SPEC, or an 1304 equivalent prior declaration, if available. */ 1305 1306 static tree 1307 register_specialization (tree spec, tree tmpl, tree args, bool is_friend, 1308 hashval_t hash) 1309 { 1310 tree fn; 1311 void **slot = NULL; 1312 spec_entry elt; 1313 1314 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL && DECL_P (spec)); 1315 1316 if (TREE_CODE (spec) == FUNCTION_DECL 1317 && uses_template_parms (DECL_TI_ARGS (spec))) 1318 /* This is the FUNCTION_DECL for a partial instantiation. Don't 1319 register it; we want the corresponding TEMPLATE_DECL instead. 1320 We use `uses_template_parms (DECL_TI_ARGS (spec))' rather than 1321 the more obvious `uses_template_parms (spec)' to avoid problems 1322 with default function arguments. In particular, given 1323 something like this: 1324 1325 template <class T> void f(T t1, T t = T()) 1326 1327 the default argument expression is not substituted for in an 1328 instantiation unless and until it is actually needed. */ 1329 return spec; 1330 1331 if (optimize_specialization_lookup_p (tmpl)) 1332 /* We don't put these specializations in the hash table, but we might 1333 want to give an error about a mismatch. */ 1334 fn = retrieve_specialization (tmpl, args, 0); 1335 else 1336 { 1337 elt.tmpl = tmpl; 1338 elt.args = args; 1339 elt.spec = spec; 1340 1341 if (hash == 0) 1342 hash = hash_specialization (&elt); 1343 1344 slot = 1345 htab_find_slot_with_hash (decl_specializations, &elt, hash, INSERT); 1346 if (*slot) 1347 fn = ((spec_entry *) *slot)->spec; 1348 else 1349 fn = NULL_TREE; 1350 } 1351 1352 /* We can sometimes try to re-register a specialization that we've 1353 already got. In particular, regenerate_decl_from_template calls 1354 duplicate_decls which will update the specialization list. But, 1355 we'll still get called again here anyhow. It's more convenient 1356 to simply allow this than to try to prevent it. */ 1357 if (fn == spec) 1358 return spec; 1359 else if (fn && DECL_TEMPLATE_SPECIALIZATION (spec)) 1360 { 1361 if (DECL_TEMPLATE_INSTANTIATION (fn)) 1362 { 1363 if (DECL_ODR_USED (fn) 1364 || DECL_EXPLICIT_INSTANTIATION (fn)) 1365 { 1366 error ("specialization of %qD after instantiation", 1367 fn); 1368 return error_mark_node; 1369 } 1370 else 1371 { 1372 tree clone; 1373 /* This situation should occur only if the first 1374 specialization is an implicit instantiation, the 1375 second is an explicit specialization, and the 1376 implicit instantiation has not yet been used. That 1377 situation can occur if we have implicitly 1378 instantiated a member function and then specialized 1379 it later. 1380 1381 We can also wind up here if a friend declaration that 1382 looked like an instantiation turns out to be a 1383 specialization: 1384 1385 template <class T> void foo(T); 1386 class S { friend void foo<>(int) }; 1387 template <> void foo(int); 1388 1389 We transform the existing DECL in place so that any 1390 pointers to it become pointers to the updated 1391 declaration. 1392 1393 If there was a definition for the template, but not 1394 for the specialization, we want this to look as if 1395 there were no definition, and vice versa. */ 1396 DECL_INITIAL (fn) = NULL_TREE; 1397 duplicate_decls (spec, fn, is_friend); 1398 /* The call to duplicate_decls will have applied 1399 [temp.expl.spec]: 1400 1401 An explicit specialization of a function template 1402 is inline only if it is explicitly declared to be, 1403 and independently of whether its function template 1404 is. 1405 1406 to the primary function; now copy the inline bits to 1407 the various clones. */ 1408 FOR_EACH_CLONE (clone, fn) 1409 { 1410 DECL_DECLARED_INLINE_P (clone) 1411 = DECL_DECLARED_INLINE_P (fn); 1412 DECL_SOURCE_LOCATION (clone) 1413 = DECL_SOURCE_LOCATION (fn); 1414 } 1415 check_specialization_namespace (fn); 1416 1417 return fn; 1418 } 1419 } 1420 else if (DECL_TEMPLATE_SPECIALIZATION (fn)) 1421 { 1422 if (!duplicate_decls (spec, fn, is_friend) && DECL_INITIAL (spec)) 1423 /* Dup decl failed, but this is a new definition. Set the 1424 line number so any errors match this new 1425 definition. */ 1426 DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (spec); 1427 1428 return fn; 1429 } 1430 } 1431 else if (fn) 1432 return duplicate_decls (spec, fn, is_friend); 1433 1434 /* A specialization must be declared in the same namespace as the 1435 template it is specializing. */ 1436 if (DECL_TEMPLATE_SPECIALIZATION (spec) 1437 && !check_specialization_namespace (tmpl)) 1438 DECL_CONTEXT (spec) = DECL_CONTEXT (tmpl); 1439 1440 if (slot != NULL /* !optimize_specialization_lookup_p (tmpl) */) 1441 { 1442 spec_entry *entry = ggc_alloc_spec_entry (); 1443 gcc_assert (tmpl && args && spec); 1444 *entry = elt; 1445 *slot = entry; 1446 if (TREE_CODE (spec) == FUNCTION_DECL && DECL_NAMESPACE_SCOPE_P (spec) 1447 && PRIMARY_TEMPLATE_P (tmpl) 1448 && DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (tmpl)) == NULL_TREE) 1449 /* TMPL is a forward declaration of a template function; keep a list 1450 of all specializations in case we need to reassign them to a friend 1451 template later in tsubst_friend_function. */ 1452 DECL_TEMPLATE_INSTANTIATIONS (tmpl) 1453 = tree_cons (args, spec, DECL_TEMPLATE_INSTANTIATIONS (tmpl)); 1454 } 1455 1456 return spec; 1457 } 1458 1459 /* Returns true iff two spec_entry nodes are equivalent. Only compares the 1460 TMPL and ARGS members, ignores SPEC. */ 1461 1462 int comparing_specializations; 1463 1464 static int 1465 eq_specializations (const void *p1, const void *p2) 1466 { 1467 const spec_entry *e1 = (const spec_entry *)p1; 1468 const spec_entry *e2 = (const spec_entry *)p2; 1469 int equal; 1470 1471 ++comparing_specializations; 1472 equal = (e1->tmpl == e2->tmpl 1473 && comp_template_args (e1->args, e2->args)); 1474 --comparing_specializations; 1475 1476 return equal; 1477 } 1478 1479 /* Returns a hash for a template TMPL and template arguments ARGS. */ 1480 1481 static hashval_t 1482 hash_tmpl_and_args (tree tmpl, tree args) 1483 { 1484 hashval_t val = DECL_UID (tmpl); 1485 return iterative_hash_template_arg (args, val); 1486 } 1487 1488 /* Returns a hash for a spec_entry node based on the TMPL and ARGS members, 1489 ignoring SPEC. */ 1490 1491 static hashval_t 1492 hash_specialization (const void *p) 1493 { 1494 const spec_entry *e = (const spec_entry *)p; 1495 return hash_tmpl_and_args (e->tmpl, e->args); 1496 } 1497 1498 /* Recursively calculate a hash value for a template argument ARG, for use 1499 in the hash tables of template specializations. */ 1500 1501 hashval_t 1502 iterative_hash_template_arg (tree arg, hashval_t val) 1503 { 1504 unsigned HOST_WIDE_INT i; 1505 enum tree_code code; 1506 char tclass; 1507 1508 if (arg == NULL_TREE) 1509 return iterative_hash_object (arg, val); 1510 1511 if (!TYPE_P (arg)) 1512 STRIP_NOPS (arg); 1513 1514 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT) 1515 /* We can get one of these when re-hashing a previous entry in the middle 1516 of substituting into a pack expansion. Just look through it. */ 1517 arg = ARGUMENT_PACK_SELECT_FROM_PACK (arg); 1518 1519 code = TREE_CODE (arg); 1520 tclass = TREE_CODE_CLASS (code); 1521 1522 val = iterative_hash_object (code, val); 1523 1524 switch (code) 1525 { 1526 case ERROR_MARK: 1527 return val; 1528 1529 case IDENTIFIER_NODE: 1530 return iterative_hash_object (IDENTIFIER_HASH_VALUE (arg), val); 1531 1532 case TREE_VEC: 1533 { 1534 int i, len = TREE_VEC_LENGTH (arg); 1535 for (i = 0; i < len; ++i) 1536 val = iterative_hash_template_arg (TREE_VEC_ELT (arg, i), val); 1537 return val; 1538 } 1539 1540 case TYPE_PACK_EXPANSION: 1541 case EXPR_PACK_EXPANSION: 1542 val = iterative_hash_template_arg (PACK_EXPANSION_PATTERN (arg), val); 1543 return iterative_hash_template_arg (PACK_EXPANSION_EXTRA_ARGS (arg), val); 1544 1545 case TYPE_ARGUMENT_PACK: 1546 case NONTYPE_ARGUMENT_PACK: 1547 return iterative_hash_template_arg (ARGUMENT_PACK_ARGS (arg), val); 1548 1549 case TREE_LIST: 1550 for (; arg; arg = TREE_CHAIN (arg)) 1551 val = iterative_hash_template_arg (TREE_VALUE (arg), val); 1552 return val; 1553 1554 case OVERLOAD: 1555 for (; arg; arg = OVL_NEXT (arg)) 1556 val = iterative_hash_template_arg (OVL_CURRENT (arg), val); 1557 return val; 1558 1559 case CONSTRUCTOR: 1560 { 1561 tree field, value; 1562 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (arg), i, field, value) 1563 { 1564 val = iterative_hash_template_arg (field, val); 1565 val = iterative_hash_template_arg (value, val); 1566 } 1567 return val; 1568 } 1569 1570 case PARM_DECL: 1571 if (!DECL_ARTIFICIAL (arg)) 1572 { 1573 val = iterative_hash_object (DECL_PARM_INDEX (arg), val); 1574 val = iterative_hash_object (DECL_PARM_LEVEL (arg), val); 1575 } 1576 return iterative_hash_template_arg (TREE_TYPE (arg), val); 1577 1578 case TARGET_EXPR: 1579 return iterative_hash_template_arg (TARGET_EXPR_INITIAL (arg), val); 1580 1581 case PTRMEM_CST: 1582 val = iterative_hash_template_arg (PTRMEM_CST_CLASS (arg), val); 1583 return iterative_hash_template_arg (PTRMEM_CST_MEMBER (arg), val); 1584 1585 case TEMPLATE_PARM_INDEX: 1586 val = iterative_hash_template_arg 1587 (TREE_TYPE (TEMPLATE_PARM_DECL (arg)), val); 1588 val = iterative_hash_object (TEMPLATE_PARM_LEVEL (arg), val); 1589 return iterative_hash_object (TEMPLATE_PARM_IDX (arg), val); 1590 1591 case TRAIT_EXPR: 1592 val = iterative_hash_object (TRAIT_EXPR_KIND (arg), val); 1593 val = iterative_hash_template_arg (TRAIT_EXPR_TYPE1 (arg), val); 1594 return iterative_hash_template_arg (TRAIT_EXPR_TYPE2 (arg), val); 1595 1596 case BASELINK: 1597 val = iterative_hash_template_arg (BINFO_TYPE (BASELINK_BINFO (arg)), 1598 val); 1599 return iterative_hash_template_arg (DECL_NAME (get_first_fn (arg)), 1600 val); 1601 1602 case MODOP_EXPR: 1603 val = iterative_hash_template_arg (TREE_OPERAND (arg, 0), val); 1604 code = TREE_CODE (TREE_OPERAND (arg, 1)); 1605 val = iterative_hash_object (code, val); 1606 return iterative_hash_template_arg (TREE_OPERAND (arg, 2), val); 1607 1608 case LAMBDA_EXPR: 1609 /* A lambda can't appear in a template arg, but don't crash on 1610 erroneous input. */ 1611 gcc_assert (seen_error ()); 1612 return val; 1613 1614 case CAST_EXPR: 1615 case IMPLICIT_CONV_EXPR: 1616 case STATIC_CAST_EXPR: 1617 case REINTERPRET_CAST_EXPR: 1618 case CONST_CAST_EXPR: 1619 case DYNAMIC_CAST_EXPR: 1620 case NEW_EXPR: 1621 val = iterative_hash_template_arg (TREE_TYPE (arg), val); 1622 /* Now hash operands as usual. */ 1623 break; 1624 1625 default: 1626 break; 1627 } 1628 1629 switch (tclass) 1630 { 1631 case tcc_type: 1632 if (TYPE_CANONICAL (arg)) 1633 return iterative_hash_object (TYPE_HASH (TYPE_CANONICAL (arg)), 1634 val); 1635 else if (TREE_CODE (arg) == DECLTYPE_TYPE) 1636 return iterative_hash_template_arg (DECLTYPE_TYPE_EXPR (arg), val); 1637 /* Otherwise just compare the types during lookup. */ 1638 return val; 1639 1640 case tcc_declaration: 1641 case tcc_constant: 1642 return iterative_hash_expr (arg, val); 1643 1644 default: 1645 gcc_assert (IS_EXPR_CODE_CLASS (tclass)); 1646 { 1647 unsigned n = cp_tree_operand_length (arg); 1648 for (i = 0; i < n; ++i) 1649 val = iterative_hash_template_arg (TREE_OPERAND (arg, i), val); 1650 return val; 1651 } 1652 } 1653 gcc_unreachable (); 1654 return 0; 1655 } 1656 1657 /* Unregister the specialization SPEC as a specialization of TMPL. 1658 Replace it with NEW_SPEC, if NEW_SPEC is non-NULL. Returns true 1659 if the SPEC was listed as a specialization of TMPL. 1660 1661 Note that SPEC has been ggc_freed, so we can't look inside it. */ 1662 1663 bool 1664 reregister_specialization (tree spec, tree tinfo, tree new_spec) 1665 { 1666 spec_entry *entry; 1667 spec_entry elt; 1668 1669 elt.tmpl = most_general_template (TI_TEMPLATE (tinfo)); 1670 elt.args = TI_ARGS (tinfo); 1671 elt.spec = NULL_TREE; 1672 1673 entry = (spec_entry *) htab_find (decl_specializations, &elt); 1674 if (entry != NULL) 1675 { 1676 gcc_assert (entry->spec == spec || entry->spec == new_spec); 1677 gcc_assert (new_spec != NULL_TREE); 1678 entry->spec = new_spec; 1679 return 1; 1680 } 1681 1682 return 0; 1683 } 1684 1685 /* Compare an entry in the local specializations hash table P1 (which 1686 is really a pointer to a TREE_LIST) with P2 (which is really a 1687 DECL). */ 1688 1689 static int 1690 eq_local_specializations (const void *p1, const void *p2) 1691 { 1692 return TREE_VALUE ((const_tree) p1) == (const_tree) p2; 1693 } 1694 1695 /* Hash P1, an entry in the local specializations table. */ 1696 1697 static hashval_t 1698 hash_local_specialization (const void* p1) 1699 { 1700 return htab_hash_pointer (TREE_VALUE ((const_tree) p1)); 1701 } 1702 1703 /* Like register_specialization, but for local declarations. We are 1704 registering SPEC, an instantiation of TMPL. */ 1705 1706 static void 1707 register_local_specialization (tree spec, tree tmpl) 1708 { 1709 void **slot; 1710 1711 slot = htab_find_slot_with_hash (local_specializations, tmpl, 1712 htab_hash_pointer (tmpl), INSERT); 1713 *slot = build_tree_list (spec, tmpl); 1714 } 1715 1716 /* TYPE is a class type. Returns true if TYPE is an explicitly 1717 specialized class. */ 1718 1719 bool 1720 explicit_class_specialization_p (tree type) 1721 { 1722 if (!CLASSTYPE_TEMPLATE_SPECIALIZATION (type)) 1723 return false; 1724 return !uses_template_parms (CLASSTYPE_TI_ARGS (type)); 1725 } 1726 1727 /* Print the list of functions at FNS, going through all the overloads 1728 for each element of the list. Alternatively, FNS can not be a 1729 TREE_LIST, in which case it will be printed together with all the 1730 overloads. 1731 1732 MORE and *STR should respectively be FALSE and NULL when the function 1733 is called from the outside. They are used internally on recursive 1734 calls. print_candidates manages the two parameters and leaves NULL 1735 in *STR when it ends. */ 1736 1737 static void 1738 print_candidates_1 (tree fns, bool more, const char **str) 1739 { 1740 tree fn, fn2; 1741 char *spaces = NULL; 1742 1743 for (fn = fns; fn; fn = OVL_NEXT (fn)) 1744 if (TREE_CODE (fn) == TREE_LIST) 1745 { 1746 for (fn2 = fn; fn2 != NULL_TREE; fn2 = TREE_CHAIN (fn2)) 1747 print_candidates_1 (TREE_VALUE (fn2), 1748 TREE_CHAIN (fn2) || more, str); 1749 } 1750 else 1751 { 1752 if (!*str) 1753 { 1754 /* Pick the prefix string. */ 1755 if (!more && !OVL_NEXT (fns)) 1756 { 1757 error ("candidate is: %+#D", OVL_CURRENT (fn)); 1758 continue; 1759 } 1760 1761 *str = _("candidates are:"); 1762 spaces = get_spaces (*str); 1763 } 1764 error ("%s %+#D", *str, OVL_CURRENT (fn)); 1765 *str = spaces ? spaces : *str; 1766 } 1767 1768 if (!more) 1769 { 1770 free (spaces); 1771 *str = NULL; 1772 } 1773 } 1774 1775 /* Print the list of candidate FNS in an error message. FNS can also 1776 be a TREE_LIST of non-functions in the case of an ambiguous lookup. */ 1777 1778 void 1779 print_candidates (tree fns) 1780 { 1781 const char *str = NULL; 1782 print_candidates_1 (fns, false, &str); 1783 gcc_assert (str == NULL); 1784 } 1785 1786 /* Returns the template (one of the functions given by TEMPLATE_ID) 1787 which can be specialized to match the indicated DECL with the 1788 explicit template args given in TEMPLATE_ID. The DECL may be 1789 NULL_TREE if none is available. In that case, the functions in 1790 TEMPLATE_ID are non-members. 1791 1792 If NEED_MEMBER_TEMPLATE is nonzero the function is known to be a 1793 specialization of a member template. 1794 1795 The TEMPLATE_COUNT is the number of references to qualifying 1796 template classes that appeared in the name of the function. See 1797 check_explicit_specialization for a more accurate description. 1798 1799 TSK indicates what kind of template declaration (if any) is being 1800 declared. TSK_TEMPLATE indicates that the declaration given by 1801 DECL, though a FUNCTION_DECL, has template parameters, and is 1802 therefore a template function. 1803 1804 The template args (those explicitly specified and those deduced) 1805 are output in a newly created vector *TARGS_OUT. 1806 1807 If it is impossible to determine the result, an error message is 1808 issued. The error_mark_node is returned to indicate failure. */ 1809 1810 static tree 1811 determine_specialization (tree template_id, 1812 tree decl, 1813 tree* targs_out, 1814 int need_member_template, 1815 int template_count, 1816 tmpl_spec_kind tsk) 1817 { 1818 tree fns; 1819 tree targs; 1820 tree explicit_targs; 1821 tree candidates = NULL_TREE; 1822 /* A TREE_LIST of templates of which DECL may be a specialization. 1823 The TREE_VALUE of each node is a TEMPLATE_DECL. The 1824 corresponding TREE_PURPOSE is the set of template arguments that, 1825 when used to instantiate the template, would produce a function 1826 with the signature of DECL. */ 1827 tree templates = NULL_TREE; 1828 int header_count; 1829 cp_binding_level *b; 1830 1831 *targs_out = NULL_TREE; 1832 1833 if (template_id == error_mark_node || decl == error_mark_node) 1834 return error_mark_node; 1835 1836 fns = TREE_OPERAND (template_id, 0); 1837 explicit_targs = TREE_OPERAND (template_id, 1); 1838 1839 if (fns == error_mark_node) 1840 return error_mark_node; 1841 1842 /* Check for baselinks. */ 1843 if (BASELINK_P (fns)) 1844 fns = BASELINK_FUNCTIONS (fns); 1845 1846 if (!is_overloaded_fn (fns)) 1847 { 1848 error ("%qD is not a function template", fns); 1849 return error_mark_node; 1850 } 1851 1852 /* Count the number of template headers specified for this 1853 specialization. */ 1854 header_count = 0; 1855 for (b = current_binding_level; 1856 b->kind == sk_template_parms; 1857 b = b->level_chain) 1858 ++header_count; 1859 1860 for (; fns; fns = OVL_NEXT (fns)) 1861 { 1862 tree fn = OVL_CURRENT (fns); 1863 1864 if (TREE_CODE (fn) == TEMPLATE_DECL) 1865 { 1866 tree decl_arg_types; 1867 tree fn_arg_types; 1868 tree insttype; 1869 1870 /* In case of explicit specialization, we need to check if 1871 the number of template headers appearing in the specialization 1872 is correct. This is usually done in check_explicit_specialization, 1873 but the check done there cannot be exhaustive when specializing 1874 member functions. Consider the following code: 1875 1876 template <> void A<int>::f(int); 1877 template <> template <> void A<int>::f(int); 1878 1879 Assuming that A<int> is not itself an explicit specialization 1880 already, the first line specializes "f" which is a non-template 1881 member function, whilst the second line specializes "f" which 1882 is a template member function. So both lines are syntactically 1883 correct, and check_explicit_specialization does not reject 1884 them. 1885 1886 Here, we can do better, as we are matching the specialization 1887 against the declarations. We count the number of template 1888 headers, and we check if they match TEMPLATE_COUNT + 1 1889 (TEMPLATE_COUNT is the number of qualifying template classes, 1890 plus there must be another header for the member template 1891 itself). 1892 1893 Notice that if header_count is zero, this is not a 1894 specialization but rather a template instantiation, so there 1895 is no check we can perform here. */ 1896 if (header_count && header_count != template_count + 1) 1897 continue; 1898 1899 /* Check that the number of template arguments at the 1900 innermost level for DECL is the same as for FN. */ 1901 if (current_binding_level->kind == sk_template_parms 1902 && !current_binding_level->explicit_spec_p 1903 && (TREE_VEC_LENGTH (DECL_INNERMOST_TEMPLATE_PARMS (fn)) 1904 != TREE_VEC_LENGTH (INNERMOST_TEMPLATE_PARMS 1905 (current_template_parms)))) 1906 continue; 1907 1908 /* DECL might be a specialization of FN. */ 1909 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl)); 1910 fn_arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn)); 1911 1912 /* For a non-static member function, we need to make sure 1913 that the const qualification is the same. Since 1914 get_bindings does not try to merge the "this" parameter, 1915 we must do the comparison explicitly. */ 1916 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn) 1917 && !same_type_p (TREE_VALUE (fn_arg_types), 1918 TREE_VALUE (decl_arg_types))) 1919 continue; 1920 1921 /* Skip the "this" parameter and, for constructors of 1922 classes with virtual bases, the VTT parameter. A 1923 full specialization of a constructor will have a VTT 1924 parameter, but a template never will. */ 1925 decl_arg_types 1926 = skip_artificial_parms_for (decl, decl_arg_types); 1927 fn_arg_types 1928 = skip_artificial_parms_for (fn, fn_arg_types); 1929 1930 /* Check that the number of function parameters matches. 1931 For example, 1932 template <class T> void f(int i = 0); 1933 template <> void f<int>(); 1934 The specialization f<int> is invalid but is not caught 1935 by get_bindings below. */ 1936 if (cxx_dialect < cxx11 1937 && list_length (fn_arg_types) != list_length (decl_arg_types)) 1938 continue; 1939 1940 /* Function templates cannot be specializations; there are 1941 no partial specializations of functions. Therefore, if 1942 the type of DECL does not match FN, there is no 1943 match. */ 1944 if (tsk == tsk_template) 1945 { 1946 if (compparms (fn_arg_types, decl_arg_types)) 1947 candidates = tree_cons (NULL_TREE, fn, candidates); 1948 continue; 1949 } 1950 1951 /* See whether this function might be a specialization of this 1952 template. */ 1953 targs = get_bindings (fn, decl, explicit_targs, /*check_ret=*/true); 1954 1955 if (!targs) 1956 /* We cannot deduce template arguments that when used to 1957 specialize TMPL will produce DECL. */ 1958 continue; 1959 1960 if (cxx_dialect >= cxx11) 1961 { 1962 /* Make sure that the deduced arguments actually work. */ 1963 insttype = tsubst (TREE_TYPE (fn), targs, tf_none, NULL_TREE); 1964 if (insttype == error_mark_node) 1965 continue; 1966 fn_arg_types 1967 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (insttype)); 1968 if (!compparms (fn_arg_types, decl_arg_types)) 1969 continue; 1970 } 1971 1972 /* Save this template, and the arguments deduced. */ 1973 templates = tree_cons (targs, fn, templates); 1974 } 1975 else if (need_member_template) 1976 /* FN is an ordinary member function, and we need a 1977 specialization of a member template. */ 1978 ; 1979 else if (TREE_CODE (fn) != FUNCTION_DECL) 1980 /* We can get IDENTIFIER_NODEs here in certain erroneous 1981 cases. */ 1982 ; 1983 else if (!DECL_FUNCTION_MEMBER_P (fn)) 1984 /* This is just an ordinary non-member function. Nothing can 1985 be a specialization of that. */ 1986 ; 1987 else if (DECL_ARTIFICIAL (fn)) 1988 /* Cannot specialize functions that are created implicitly. */ 1989 ; 1990 else 1991 { 1992 tree decl_arg_types; 1993 1994 /* This is an ordinary member function. However, since 1995 we're here, we can assume it's enclosing class is a 1996 template class. For example, 1997 1998 template <typename T> struct S { void f(); }; 1999 template <> void S<int>::f() {} 2000 2001 Here, S<int>::f is a non-template, but S<int> is a 2002 template class. If FN has the same type as DECL, we 2003 might be in business. */ 2004 2005 if (!DECL_TEMPLATE_INFO (fn)) 2006 /* Its enclosing class is an explicit specialization 2007 of a template class. This is not a candidate. */ 2008 continue; 2009 2010 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)), 2011 TREE_TYPE (TREE_TYPE (fn)))) 2012 /* The return types differ. */ 2013 continue; 2014 2015 /* Adjust the type of DECL in case FN is a static member. */ 2016 decl_arg_types = TYPE_ARG_TYPES (TREE_TYPE (decl)); 2017 if (DECL_STATIC_FUNCTION_P (fn) 2018 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)) 2019 decl_arg_types = TREE_CHAIN (decl_arg_types); 2020 2021 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)), 2022 decl_arg_types)) 2023 /* They match! */ 2024 candidates = tree_cons (NULL_TREE, fn, candidates); 2025 } 2026 } 2027 2028 if (templates && TREE_CHAIN (templates)) 2029 { 2030 /* We have: 2031 2032 [temp.expl.spec] 2033 2034 It is possible for a specialization with a given function 2035 signature to be instantiated from more than one function 2036 template. In such cases, explicit specification of the 2037 template arguments must be used to uniquely identify the 2038 function template specialization being specialized. 2039 2040 Note that here, there's no suggestion that we're supposed to 2041 determine which of the candidate templates is most 2042 specialized. However, we, also have: 2043 2044 [temp.func.order] 2045 2046 Partial ordering of overloaded function template 2047 declarations is used in the following contexts to select 2048 the function template to which a function template 2049 specialization refers: 2050 2051 -- when an explicit specialization refers to a function 2052 template. 2053 2054 So, we do use the partial ordering rules, at least for now. 2055 This extension can only serve to make invalid programs valid, 2056 so it's safe. And, there is strong anecdotal evidence that 2057 the committee intended the partial ordering rules to apply; 2058 the EDG front end has that behavior, and John Spicer claims 2059 that the committee simply forgot to delete the wording in 2060 [temp.expl.spec]. */ 2061 tree tmpl = most_specialized_instantiation (templates); 2062 if (tmpl != error_mark_node) 2063 { 2064 templates = tmpl; 2065 TREE_CHAIN (templates) = NULL_TREE; 2066 } 2067 } 2068 2069 if (templates == NULL_TREE && candidates == NULL_TREE) 2070 { 2071 error ("template-id %qD for %q+D does not match any template " 2072 "declaration", template_id, decl); 2073 if (header_count && header_count != template_count + 1) 2074 inform (input_location, "saw %d %<template<>%>, need %d for " 2075 "specializing a member function template", 2076 header_count, template_count + 1); 2077 return error_mark_node; 2078 } 2079 else if ((templates && TREE_CHAIN (templates)) 2080 || (candidates && TREE_CHAIN (candidates)) 2081 || (templates && candidates)) 2082 { 2083 error ("ambiguous template specialization %qD for %q+D", 2084 template_id, decl); 2085 candidates = chainon (candidates, templates); 2086 print_candidates (candidates); 2087 return error_mark_node; 2088 } 2089 2090 /* We have one, and exactly one, match. */ 2091 if (candidates) 2092 { 2093 tree fn = TREE_VALUE (candidates); 2094 *targs_out = copy_node (DECL_TI_ARGS (fn)); 2095 /* DECL is a re-declaration or partial instantiation of a template 2096 function. */ 2097 if (TREE_CODE (fn) == TEMPLATE_DECL) 2098 return fn; 2099 /* It was a specialization of an ordinary member function in a 2100 template class. */ 2101 return DECL_TI_TEMPLATE (fn); 2102 } 2103 2104 /* It was a specialization of a template. */ 2105 targs = DECL_TI_ARGS (DECL_TEMPLATE_RESULT (TREE_VALUE (templates))); 2106 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (targs)) 2107 { 2108 *targs_out = copy_node (targs); 2109 SET_TMPL_ARGS_LEVEL (*targs_out, 2110 TMPL_ARGS_DEPTH (*targs_out), 2111 TREE_PURPOSE (templates)); 2112 } 2113 else 2114 *targs_out = TREE_PURPOSE (templates); 2115 return TREE_VALUE (templates); 2116 } 2117 2118 /* Returns a chain of parameter types, exactly like the SPEC_TYPES, 2119 but with the default argument values filled in from those in the 2120 TMPL_TYPES. */ 2121 2122 static tree 2123 copy_default_args_to_explicit_spec_1 (tree spec_types, 2124 tree tmpl_types) 2125 { 2126 tree new_spec_types; 2127 2128 if (!spec_types) 2129 return NULL_TREE; 2130 2131 if (spec_types == void_list_node) 2132 return void_list_node; 2133 2134 /* Substitute into the rest of the list. */ 2135 new_spec_types = 2136 copy_default_args_to_explicit_spec_1 (TREE_CHAIN (spec_types), 2137 TREE_CHAIN (tmpl_types)); 2138 2139 /* Add the default argument for this parameter. */ 2140 return hash_tree_cons (TREE_PURPOSE (tmpl_types), 2141 TREE_VALUE (spec_types), 2142 new_spec_types); 2143 } 2144 2145 /* DECL is an explicit specialization. Replicate default arguments 2146 from the template it specializes. (That way, code like: 2147 2148 template <class T> void f(T = 3); 2149 template <> void f(double); 2150 void g () { f (); } 2151 2152 works, as required.) An alternative approach would be to look up 2153 the correct default arguments at the call-site, but this approach 2154 is consistent with how implicit instantiations are handled. */ 2155 2156 static void 2157 copy_default_args_to_explicit_spec (tree decl) 2158 { 2159 tree tmpl; 2160 tree spec_types; 2161 tree tmpl_types; 2162 tree new_spec_types; 2163 tree old_type; 2164 tree new_type; 2165 tree t; 2166 tree object_type = NULL_TREE; 2167 tree in_charge = NULL_TREE; 2168 tree vtt = NULL_TREE; 2169 2170 /* See if there's anything we need to do. */ 2171 tmpl = DECL_TI_TEMPLATE (decl); 2172 tmpl_types = TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (tmpl))); 2173 for (t = tmpl_types; t; t = TREE_CHAIN (t)) 2174 if (TREE_PURPOSE (t)) 2175 break; 2176 if (!t) 2177 return; 2178 2179 old_type = TREE_TYPE (decl); 2180 spec_types = TYPE_ARG_TYPES (old_type); 2181 2182 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)) 2183 { 2184 /* Remove the this pointer, but remember the object's type for 2185 CV quals. */ 2186 object_type = TREE_TYPE (TREE_VALUE (spec_types)); 2187 spec_types = TREE_CHAIN (spec_types); 2188 tmpl_types = TREE_CHAIN (tmpl_types); 2189 2190 if (DECL_HAS_IN_CHARGE_PARM_P (decl)) 2191 { 2192 /* DECL may contain more parameters than TMPL due to the extra 2193 in-charge parameter in constructors and destructors. */ 2194 in_charge = spec_types; 2195 spec_types = TREE_CHAIN (spec_types); 2196 } 2197 if (DECL_HAS_VTT_PARM_P (decl)) 2198 { 2199 vtt = spec_types; 2200 spec_types = TREE_CHAIN (spec_types); 2201 } 2202 } 2203 2204 /* Compute the merged default arguments. */ 2205 new_spec_types = 2206 copy_default_args_to_explicit_spec_1 (spec_types, tmpl_types); 2207 2208 /* Compute the new FUNCTION_TYPE. */ 2209 if (object_type) 2210 { 2211 if (vtt) 2212 new_spec_types = hash_tree_cons (TREE_PURPOSE (vtt), 2213 TREE_VALUE (vtt), 2214 new_spec_types); 2215 2216 if (in_charge) 2217 /* Put the in-charge parameter back. */ 2218 new_spec_types = hash_tree_cons (TREE_PURPOSE (in_charge), 2219 TREE_VALUE (in_charge), 2220 new_spec_types); 2221 2222 new_type = build_method_type_directly (object_type, 2223 TREE_TYPE (old_type), 2224 new_spec_types); 2225 } 2226 else 2227 new_type = build_function_type (TREE_TYPE (old_type), 2228 new_spec_types); 2229 new_type = cp_build_type_attribute_variant (new_type, 2230 TYPE_ATTRIBUTES (old_type)); 2231 new_type = build_exception_variant (new_type, 2232 TYPE_RAISES_EXCEPTIONS (old_type)); 2233 TREE_TYPE (decl) = new_type; 2234 } 2235 2236 /* Check to see if the function just declared, as indicated in 2237 DECLARATOR, and in DECL, is a specialization of a function 2238 template. We may also discover that the declaration is an explicit 2239 instantiation at this point. 2240 2241 Returns DECL, or an equivalent declaration that should be used 2242 instead if all goes well. Issues an error message if something is 2243 amiss. Returns error_mark_node if the error is not easily 2244 recoverable. 2245 2246 FLAGS is a bitmask consisting of the following flags: 2247 2248 2: The function has a definition. 2249 4: The function is a friend. 2250 2251 The TEMPLATE_COUNT is the number of references to qualifying 2252 template classes that appeared in the name of the function. For 2253 example, in 2254 2255 template <class T> struct S { void f(); }; 2256 void S<int>::f(); 2257 2258 the TEMPLATE_COUNT would be 1. However, explicitly specialized 2259 classes are not counted in the TEMPLATE_COUNT, so that in 2260 2261 template <class T> struct S {}; 2262 template <> struct S<int> { void f(); } 2263 template <> void S<int>::f(); 2264 2265 the TEMPLATE_COUNT would be 0. (Note that this declaration is 2266 invalid; there should be no template <>.) 2267 2268 If the function is a specialization, it is marked as such via 2269 DECL_TEMPLATE_SPECIALIZATION. Furthermore, its DECL_TEMPLATE_INFO 2270 is set up correctly, and it is added to the list of specializations 2271 for that template. */ 2272 2273 tree 2274 check_explicit_specialization (tree declarator, 2275 tree decl, 2276 int template_count, 2277 int flags) 2278 { 2279 int have_def = flags & 2; 2280 int is_friend = flags & 4; 2281 int specialization = 0; 2282 int explicit_instantiation = 0; 2283 int member_specialization = 0; 2284 tree ctype = DECL_CLASS_CONTEXT (decl); 2285 tree dname = DECL_NAME (decl); 2286 tmpl_spec_kind tsk; 2287 2288 if (is_friend) 2289 { 2290 if (!processing_specialization) 2291 tsk = tsk_none; 2292 else 2293 tsk = tsk_excessive_parms; 2294 } 2295 else 2296 tsk = current_tmpl_spec_kind (template_count); 2297 2298 switch (tsk) 2299 { 2300 case tsk_none: 2301 if (processing_specialization) 2302 { 2303 specialization = 1; 2304 SET_DECL_TEMPLATE_SPECIALIZATION (decl); 2305 } 2306 else if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR) 2307 { 2308 if (is_friend) 2309 /* This could be something like: 2310 2311 template <class T> void f(T); 2312 class S { friend void f<>(int); } */ 2313 specialization = 1; 2314 else 2315 { 2316 /* This case handles bogus declarations like template <> 2317 template <class T> void f<int>(); */ 2318 2319 error ("template-id %qD in declaration of primary template", 2320 declarator); 2321 return decl; 2322 } 2323 } 2324 break; 2325 2326 case tsk_invalid_member_spec: 2327 /* The error has already been reported in 2328 check_specialization_scope. */ 2329 return error_mark_node; 2330 2331 case tsk_invalid_expl_inst: 2332 error ("template parameter list used in explicit instantiation"); 2333 2334 /* Fall through. */ 2335 2336 case tsk_expl_inst: 2337 if (have_def) 2338 error ("definition provided for explicit instantiation"); 2339 2340 explicit_instantiation = 1; 2341 break; 2342 2343 case tsk_excessive_parms: 2344 case tsk_insufficient_parms: 2345 if (tsk == tsk_excessive_parms) 2346 error ("too many template parameter lists in declaration of %qD", 2347 decl); 2348 else if (template_header_count) 2349 error("too few template parameter lists in declaration of %qD", decl); 2350 else 2351 error("explicit specialization of %qD must be introduced by " 2352 "%<template <>%>", decl); 2353 2354 /* Fall through. */ 2355 case tsk_expl_spec: 2356 SET_DECL_TEMPLATE_SPECIALIZATION (decl); 2357 if (ctype) 2358 member_specialization = 1; 2359 else 2360 specialization = 1; 2361 break; 2362 2363 case tsk_template: 2364 if (TREE_CODE (declarator) == TEMPLATE_ID_EXPR) 2365 { 2366 /* This case handles bogus declarations like template <> 2367 template <class T> void f<int>(); */ 2368 2369 if (uses_template_parms (declarator)) 2370 error ("function template partial specialization %qD " 2371 "is not allowed", declarator); 2372 else 2373 error ("template-id %qD in declaration of primary template", 2374 declarator); 2375 return decl; 2376 } 2377 2378 if (ctype && CLASSTYPE_TEMPLATE_INSTANTIATION (ctype)) 2379 /* This is a specialization of a member template, without 2380 specialization the containing class. Something like: 2381 2382 template <class T> struct S { 2383 template <class U> void f (U); 2384 }; 2385 template <> template <class U> void S<int>::f(U) {} 2386 2387 That's a specialization -- but of the entire template. */ 2388 specialization = 1; 2389 break; 2390 2391 default: 2392 gcc_unreachable (); 2393 } 2394 2395 if (specialization || member_specialization) 2396 { 2397 tree t = TYPE_ARG_TYPES (TREE_TYPE (decl)); 2398 for (; t; t = TREE_CHAIN (t)) 2399 if (TREE_PURPOSE (t)) 2400 { 2401 permerror (input_location, 2402 "default argument specified in explicit specialization"); 2403 break; 2404 } 2405 } 2406 2407 if (specialization || member_specialization || explicit_instantiation) 2408 { 2409 tree tmpl = NULL_TREE; 2410 tree targs = NULL_TREE; 2411 2412 /* Make sure that the declarator is a TEMPLATE_ID_EXPR. */ 2413 if (TREE_CODE (declarator) != TEMPLATE_ID_EXPR) 2414 { 2415 tree fns; 2416 2417 gcc_assert (TREE_CODE (declarator) == IDENTIFIER_NODE); 2418 if (ctype) 2419 fns = dname; 2420 else 2421 { 2422 /* If there is no class context, the explicit instantiation 2423 must be at namespace scope. */ 2424 gcc_assert (DECL_NAMESPACE_SCOPE_P (decl)); 2425 2426 /* Find the namespace binding, using the declaration 2427 context. */ 2428 fns = lookup_qualified_name (CP_DECL_CONTEXT (decl), dname, 2429 false, true); 2430 if (fns == error_mark_node || !is_overloaded_fn (fns)) 2431 { 2432 error ("%qD is not a template function", dname); 2433 fns = error_mark_node; 2434 } 2435 else 2436 { 2437 tree fn = OVL_CURRENT (fns); 2438 if (!is_associated_namespace (CP_DECL_CONTEXT (decl), 2439 CP_DECL_CONTEXT (fn))) 2440 error ("%qD is not declared in %qD", 2441 decl, current_namespace); 2442 } 2443 } 2444 2445 declarator = lookup_template_function (fns, NULL_TREE); 2446 } 2447 2448 if (declarator == error_mark_node) 2449 return error_mark_node; 2450 2451 if (ctype != NULL_TREE && TYPE_BEING_DEFINED (ctype)) 2452 { 2453 if (!explicit_instantiation) 2454 /* A specialization in class scope. This is invalid, 2455 but the error will already have been flagged by 2456 check_specialization_scope. */ 2457 return error_mark_node; 2458 else 2459 { 2460 /* It's not valid to write an explicit instantiation in 2461 class scope, e.g.: 2462 2463 class C { template void f(); } 2464 2465 This case is caught by the parser. However, on 2466 something like: 2467 2468 template class C { void f(); }; 2469 2470 (which is invalid) we can get here. The error will be 2471 issued later. */ 2472 ; 2473 } 2474 2475 return decl; 2476 } 2477 else if (ctype != NULL_TREE 2478 && (TREE_CODE (TREE_OPERAND (declarator, 0)) == 2479 IDENTIFIER_NODE)) 2480 { 2481 /* Find the list of functions in ctype that have the same 2482 name as the declared function. */ 2483 tree name = TREE_OPERAND (declarator, 0); 2484 tree fns = NULL_TREE; 2485 int idx; 2486 2487 if (constructor_name_p (name, ctype)) 2488 { 2489 int is_constructor = DECL_CONSTRUCTOR_P (decl); 2490 2491 if (is_constructor ? !TYPE_HAS_USER_CONSTRUCTOR (ctype) 2492 : !CLASSTYPE_DESTRUCTORS (ctype)) 2493 { 2494 /* From [temp.expl.spec]: 2495 2496 If such an explicit specialization for the member 2497 of a class template names an implicitly-declared 2498 special member function (clause _special_), the 2499 program is ill-formed. 2500 2501 Similar language is found in [temp.explicit]. */ 2502 error ("specialization of implicitly-declared special member function"); 2503 return error_mark_node; 2504 } 2505 2506 name = is_constructor ? ctor_identifier : dtor_identifier; 2507 } 2508 2509 if (!DECL_CONV_FN_P (decl)) 2510 { 2511 idx = lookup_fnfields_1 (ctype, name); 2512 if (idx >= 0) 2513 fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (ctype), idx); 2514 } 2515 else 2516 { 2517 VEC(tree,gc) *methods; 2518 tree ovl; 2519 2520 /* For a type-conversion operator, we cannot do a 2521 name-based lookup. We might be looking for `operator 2522 int' which will be a specialization of `operator T'. 2523 So, we find *all* the conversion operators, and then 2524 select from them. */ 2525 fns = NULL_TREE; 2526 2527 methods = CLASSTYPE_METHOD_VEC (ctype); 2528 if (methods) 2529 for (idx = CLASSTYPE_FIRST_CONVERSION_SLOT; 2530 VEC_iterate (tree, methods, idx, ovl); 2531 ++idx) 2532 { 2533 if (!DECL_CONV_FN_P (OVL_CURRENT (ovl))) 2534 /* There are no more conversion functions. */ 2535 break; 2536 2537 /* Glue all these conversion functions together 2538 with those we already have. */ 2539 for (; ovl; ovl = OVL_NEXT (ovl)) 2540 fns = ovl_cons (OVL_CURRENT (ovl), fns); 2541 } 2542 } 2543 2544 if (fns == NULL_TREE) 2545 { 2546 error ("no member function %qD declared in %qT", name, ctype); 2547 return error_mark_node; 2548 } 2549 else 2550 TREE_OPERAND (declarator, 0) = fns; 2551 } 2552 2553 /* Figure out what exactly is being specialized at this point. 2554 Note that for an explicit instantiation, even one for a 2555 member function, we cannot tell apriori whether the 2556 instantiation is for a member template, or just a member 2557 function of a template class. Even if a member template is 2558 being instantiated, the member template arguments may be 2559 elided if they can be deduced from the rest of the 2560 declaration. */ 2561 tmpl = determine_specialization (declarator, decl, 2562 &targs, 2563 member_specialization, 2564 template_count, 2565 tsk); 2566 2567 if (!tmpl || tmpl == error_mark_node) 2568 /* We couldn't figure out what this declaration was 2569 specializing. */ 2570 return error_mark_node; 2571 else 2572 { 2573 tree gen_tmpl = most_general_template (tmpl); 2574 2575 if (explicit_instantiation) 2576 { 2577 /* We don't set DECL_EXPLICIT_INSTANTIATION here; that 2578 is done by do_decl_instantiation later. */ 2579 2580 int arg_depth = TMPL_ARGS_DEPTH (targs); 2581 int parm_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)); 2582 2583 if (arg_depth > parm_depth) 2584 { 2585 /* If TMPL is not the most general template (for 2586 example, if TMPL is a friend template that is 2587 injected into namespace scope), then there will 2588 be too many levels of TARGS. Remove some of them 2589 here. */ 2590 int i; 2591 tree new_targs; 2592 2593 new_targs = make_tree_vec (parm_depth); 2594 for (i = arg_depth - parm_depth; i < arg_depth; ++i) 2595 TREE_VEC_ELT (new_targs, i - (arg_depth - parm_depth)) 2596 = TREE_VEC_ELT (targs, i); 2597 targs = new_targs; 2598 } 2599 2600 return instantiate_template (tmpl, targs, tf_error); 2601 } 2602 2603 /* If we thought that the DECL was a member function, but it 2604 turns out to be specializing a static member function, 2605 make DECL a static member function as well. */ 2606 if (DECL_STATIC_FUNCTION_P (tmpl) 2607 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)) 2608 revert_static_member_fn (decl); 2609 2610 /* If this is a specialization of a member template of a 2611 template class, we want to return the TEMPLATE_DECL, not 2612 the specialization of it. */ 2613 if (tsk == tsk_template) 2614 { 2615 tree result = DECL_TEMPLATE_RESULT (tmpl); 2616 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl); 2617 DECL_INITIAL (result) = NULL_TREE; 2618 if (have_def) 2619 { 2620 tree parm; 2621 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl); 2622 DECL_SOURCE_LOCATION (result) 2623 = DECL_SOURCE_LOCATION (decl); 2624 /* We want to use the argument list specified in the 2625 definition, not in the original declaration. */ 2626 DECL_ARGUMENTS (result) = DECL_ARGUMENTS (decl); 2627 for (parm = DECL_ARGUMENTS (result); parm; 2628 parm = DECL_CHAIN (parm)) 2629 DECL_CONTEXT (parm) = result; 2630 } 2631 return register_specialization (tmpl, gen_tmpl, targs, 2632 is_friend, 0); 2633 } 2634 2635 /* Set up the DECL_TEMPLATE_INFO for DECL. */ 2636 DECL_TEMPLATE_INFO (decl) = build_template_info (tmpl, targs); 2637 2638 /* Inherit default function arguments from the template 2639 DECL is specializing. */ 2640 copy_default_args_to_explicit_spec (decl); 2641 2642 /* This specialization has the same protection as the 2643 template it specializes. */ 2644 TREE_PRIVATE (decl) = TREE_PRIVATE (gen_tmpl); 2645 TREE_PROTECTED (decl) = TREE_PROTECTED (gen_tmpl); 2646 2647 /* 7.1.1-1 [dcl.stc] 2648 2649 A storage-class-specifier shall not be specified in an 2650 explicit specialization... 2651 2652 The parser rejects these, so unless action is taken here, 2653 explicit function specializations will always appear with 2654 global linkage. 2655 2656 The action recommended by the C++ CWG in response to C++ 2657 defect report 605 is to make the storage class and linkage 2658 of the explicit specialization match the templated function: 2659 2660 http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#605 2661 */ 2662 if (tsk == tsk_expl_spec && DECL_FUNCTION_TEMPLATE_P (gen_tmpl)) 2663 { 2664 tree tmpl_func = DECL_TEMPLATE_RESULT (gen_tmpl); 2665 gcc_assert (TREE_CODE (tmpl_func) == FUNCTION_DECL); 2666 2667 /* This specialization has the same linkage and visibility as 2668 the function template it specializes. */ 2669 TREE_PUBLIC (decl) = TREE_PUBLIC (tmpl_func); 2670 if (! TREE_PUBLIC (decl)) 2671 { 2672 DECL_INTERFACE_KNOWN (decl) = 1; 2673 DECL_NOT_REALLY_EXTERN (decl) = 1; 2674 } 2675 DECL_THIS_STATIC (decl) = DECL_THIS_STATIC (tmpl_func); 2676 if (DECL_VISIBILITY_SPECIFIED (tmpl_func)) 2677 { 2678 DECL_VISIBILITY_SPECIFIED (decl) = 1; 2679 DECL_VISIBILITY (decl) = DECL_VISIBILITY (tmpl_func); 2680 } 2681 } 2682 2683 /* If DECL is a friend declaration, declared using an 2684 unqualified name, the namespace associated with DECL may 2685 have been set incorrectly. For example, in: 2686 2687 template <typename T> void f(T); 2688 namespace N { 2689 struct S { friend void f<int>(int); } 2690 } 2691 2692 we will have set the DECL_CONTEXT for the friend 2693 declaration to N, rather than to the global namespace. */ 2694 if (DECL_NAMESPACE_SCOPE_P (decl)) 2695 DECL_CONTEXT (decl) = DECL_CONTEXT (tmpl); 2696 2697 if (is_friend && !have_def) 2698 /* This is not really a declaration of a specialization. 2699 It's just the name of an instantiation. But, it's not 2700 a request for an instantiation, either. */ 2701 SET_DECL_IMPLICIT_INSTANTIATION (decl); 2702 else if (DECL_CONSTRUCTOR_P (decl) || DECL_DESTRUCTOR_P (decl)) 2703 /* This is indeed a specialization. In case of constructors 2704 and destructors, we need in-charge and not-in-charge 2705 versions in V3 ABI. */ 2706 clone_function_decl (decl, /*update_method_vec_p=*/0); 2707 2708 /* Register this specialization so that we can find it 2709 again. */ 2710 decl = register_specialization (decl, gen_tmpl, targs, is_friend, 0); 2711 } 2712 } 2713 2714 return decl; 2715 } 2716 2717 /* Returns 1 iff PARMS1 and PARMS2 are identical sets of template 2718 parameters. These are represented in the same format used for 2719 DECL_TEMPLATE_PARMS. */ 2720 2721 int 2722 comp_template_parms (const_tree parms1, const_tree parms2) 2723 { 2724 const_tree p1; 2725 const_tree p2; 2726 2727 if (parms1 == parms2) 2728 return 1; 2729 2730 for (p1 = parms1, p2 = parms2; 2731 p1 != NULL_TREE && p2 != NULL_TREE; 2732 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2)) 2733 { 2734 tree t1 = TREE_VALUE (p1); 2735 tree t2 = TREE_VALUE (p2); 2736 int i; 2737 2738 gcc_assert (TREE_CODE (t1) == TREE_VEC); 2739 gcc_assert (TREE_CODE (t2) == TREE_VEC); 2740 2741 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2)) 2742 return 0; 2743 2744 for (i = 0; i < TREE_VEC_LENGTH (t2); ++i) 2745 { 2746 tree parm1 = TREE_VALUE (TREE_VEC_ELT (t1, i)); 2747 tree parm2 = TREE_VALUE (TREE_VEC_ELT (t2, i)); 2748 2749 /* If either of the template parameters are invalid, assume 2750 they match for the sake of error recovery. */ 2751 if (parm1 == error_mark_node || parm2 == error_mark_node) 2752 return 1; 2753 2754 if (TREE_CODE (parm1) != TREE_CODE (parm2)) 2755 return 0; 2756 2757 if (TREE_CODE (parm1) == TEMPLATE_TYPE_PARM 2758 && (TEMPLATE_TYPE_PARAMETER_PACK (parm1) 2759 == TEMPLATE_TYPE_PARAMETER_PACK (parm2))) 2760 continue; 2761 else if (!same_type_p (TREE_TYPE (parm1), TREE_TYPE (parm2))) 2762 return 0; 2763 } 2764 } 2765 2766 if ((p1 != NULL_TREE) != (p2 != NULL_TREE)) 2767 /* One set of parameters has more parameters lists than the 2768 other. */ 2769 return 0; 2770 2771 return 1; 2772 } 2773 2774 /* Determine whether PARM is a parameter pack. */ 2775 2776 bool 2777 template_parameter_pack_p (const_tree parm) 2778 { 2779 /* Determine if we have a non-type template parameter pack. */ 2780 if (TREE_CODE (parm) == PARM_DECL) 2781 return (DECL_TEMPLATE_PARM_P (parm) 2782 && TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))); 2783 if (TREE_CODE (parm) == TEMPLATE_PARM_INDEX) 2784 return TEMPLATE_PARM_PARAMETER_PACK (parm); 2785 2786 /* If this is a list of template parameters, we could get a 2787 TYPE_DECL or a TEMPLATE_DECL. */ 2788 if (TREE_CODE (parm) == TYPE_DECL || TREE_CODE (parm) == TEMPLATE_DECL) 2789 parm = TREE_TYPE (parm); 2790 2791 /* Otherwise it must be a type template parameter. */ 2792 return ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM 2793 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM) 2794 && TEMPLATE_TYPE_PARAMETER_PACK (parm)); 2795 } 2796 2797 /* Determine if T is a function parameter pack. */ 2798 2799 bool 2800 function_parameter_pack_p (const_tree t) 2801 { 2802 if (t && TREE_CODE (t) == PARM_DECL) 2803 return FUNCTION_PARAMETER_PACK_P (t); 2804 return false; 2805 } 2806 2807 /* Return the function template declaration of PRIMARY_FUNC_TMPL_INST. 2808 PRIMARY_FUNC_TMPL_INST is a primary function template instantiation. */ 2809 2810 tree 2811 get_function_template_decl (const_tree primary_func_tmpl_inst) 2812 { 2813 if (! primary_func_tmpl_inst 2814 || TREE_CODE (primary_func_tmpl_inst) != FUNCTION_DECL 2815 || ! primary_template_instantiation_p (primary_func_tmpl_inst)) 2816 return NULL; 2817 2818 return DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (primary_func_tmpl_inst)); 2819 } 2820 2821 /* Return true iff the function parameter PARAM_DECL was expanded 2822 from the function parameter pack PACK. */ 2823 2824 bool 2825 function_parameter_expanded_from_pack_p (tree param_decl, tree pack) 2826 { 2827 if (DECL_ARTIFICIAL (param_decl) 2828 || !function_parameter_pack_p (pack)) 2829 return false; 2830 2831 /* The parameter pack and its pack arguments have the same 2832 DECL_PARM_INDEX. */ 2833 return DECL_PARM_INDEX (pack) == DECL_PARM_INDEX (param_decl); 2834 } 2835 2836 /* Determine whether ARGS describes a variadic template args list, 2837 i.e., one that is terminated by a template argument pack. */ 2838 2839 static bool 2840 template_args_variadic_p (tree args) 2841 { 2842 int nargs; 2843 tree last_parm; 2844 2845 if (args == NULL_TREE) 2846 return false; 2847 2848 args = INNERMOST_TEMPLATE_ARGS (args); 2849 nargs = TREE_VEC_LENGTH (args); 2850 2851 if (nargs == 0) 2852 return false; 2853 2854 last_parm = TREE_VEC_ELT (args, nargs - 1); 2855 2856 return ARGUMENT_PACK_P (last_parm); 2857 } 2858 2859 /* Generate a new name for the parameter pack name NAME (an 2860 IDENTIFIER_NODE) that incorporates its */ 2861 2862 static tree 2863 make_ith_pack_parameter_name (tree name, int i) 2864 { 2865 /* Munge the name to include the parameter index. */ 2866 #define NUMBUF_LEN 128 2867 char numbuf[NUMBUF_LEN]; 2868 char* newname; 2869 int newname_len; 2870 2871 if (name == NULL_TREE) 2872 return name; 2873 snprintf (numbuf, NUMBUF_LEN, "%i", i); 2874 newname_len = IDENTIFIER_LENGTH (name) 2875 + strlen (numbuf) + 2; 2876 newname = (char*)alloca (newname_len); 2877 snprintf (newname, newname_len, 2878 "%s#%i", IDENTIFIER_POINTER (name), i); 2879 return get_identifier (newname); 2880 } 2881 2882 /* Return true if T is a primary function, class or alias template 2883 instantiation. */ 2884 2885 bool 2886 primary_template_instantiation_p (const_tree t) 2887 { 2888 if (!t) 2889 return false; 2890 2891 if (TREE_CODE (t) == FUNCTION_DECL) 2892 return DECL_LANG_SPECIFIC (t) 2893 && DECL_TEMPLATE_INSTANTIATION (t) 2894 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (t)); 2895 else if (CLASS_TYPE_P (t) && !TYPE_DECL_ALIAS_P (TYPE_NAME (t))) 2896 return CLASSTYPE_TEMPLATE_INSTANTIATION (t) 2897 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t)); 2898 else if (TYPE_P (t) 2899 && TYPE_TEMPLATE_INFO (t) 2900 && PRIMARY_TEMPLATE_P (TYPE_TI_TEMPLATE (t)) 2901 && DECL_TEMPLATE_INSTANTIATION (TYPE_NAME (t))) 2902 return true; 2903 return false; 2904 } 2905 2906 /* Return true if PARM is a template template parameter. */ 2907 2908 bool 2909 template_template_parameter_p (const_tree parm) 2910 { 2911 return DECL_TEMPLATE_TEMPLATE_PARM_P (parm); 2912 } 2913 2914 /* Return the template parameters of T if T is a 2915 primary template instantiation, NULL otherwise. */ 2916 2917 tree 2918 get_primary_template_innermost_parameters (const_tree t) 2919 { 2920 tree parms = NULL, template_info = NULL; 2921 2922 if ((template_info = get_template_info (t)) 2923 && primary_template_instantiation_p (t)) 2924 parms = INNERMOST_TEMPLATE_PARMS 2925 (DECL_TEMPLATE_PARMS (TI_TEMPLATE (template_info))); 2926 2927 return parms; 2928 } 2929 2930 /* Return the template parameters of the LEVELth level from the full list 2931 of template parameters PARMS. */ 2932 2933 tree 2934 get_template_parms_at_level (tree parms, int level) 2935 { 2936 tree p; 2937 if (!parms 2938 || TREE_CODE (parms) != TREE_LIST 2939 || level > TMPL_PARMS_DEPTH (parms)) 2940 return NULL_TREE; 2941 2942 for (p = parms; p; p = TREE_CHAIN (p)) 2943 if (TMPL_PARMS_DEPTH (p) == level) 2944 return p; 2945 2946 return NULL_TREE; 2947 } 2948 2949 /* Returns the template arguments of T if T is a template instantiation, 2950 NULL otherwise. */ 2951 2952 tree 2953 get_template_innermost_arguments (const_tree t) 2954 { 2955 tree args = NULL, template_info = NULL; 2956 2957 if ((template_info = get_template_info (t)) 2958 && TI_ARGS (template_info)) 2959 args = INNERMOST_TEMPLATE_ARGS (TI_ARGS (template_info)); 2960 2961 return args; 2962 } 2963 2964 /* Return the argument pack elements of T if T is a template argument pack, 2965 NULL otherwise. */ 2966 2967 tree 2968 get_template_argument_pack_elems (const_tree t) 2969 { 2970 if (TREE_CODE (t) != TYPE_ARGUMENT_PACK 2971 && TREE_CODE (t) != NONTYPE_ARGUMENT_PACK) 2972 return NULL; 2973 2974 return ARGUMENT_PACK_ARGS (t); 2975 } 2976 2977 /* Structure used to track the progress of find_parameter_packs_r. */ 2978 struct find_parameter_pack_data 2979 { 2980 /* TREE_LIST that will contain all of the parameter packs found by 2981 the traversal. */ 2982 tree* parameter_packs; 2983 2984 /* Set of AST nodes that have been visited by the traversal. */ 2985 struct pointer_set_t *visited; 2986 }; 2987 2988 /* Identifies all of the argument packs that occur in a template 2989 argument and appends them to the TREE_LIST inside DATA, which is a 2990 find_parameter_pack_data structure. This is a subroutine of 2991 make_pack_expansion and uses_parameter_packs. */ 2992 static tree 2993 find_parameter_packs_r (tree *tp, int *walk_subtrees, void* data) 2994 { 2995 tree t = *tp; 2996 struct find_parameter_pack_data* ppd = 2997 (struct find_parameter_pack_data*)data; 2998 bool parameter_pack_p = false; 2999 3000 /* Handle type aliases/typedefs. */ 3001 if (TYPE_P (t) 3002 && TYPE_NAME (t) 3003 && TREE_CODE (TYPE_NAME (t)) == TYPE_DECL 3004 && TYPE_DECL_ALIAS_P (TYPE_NAME (t))) 3005 { 3006 if (TYPE_TEMPLATE_INFO (t)) 3007 cp_walk_tree (&TYPE_TI_ARGS (t), 3008 &find_parameter_packs_r, 3009 ppd, ppd->visited); 3010 *walk_subtrees = 0; 3011 return NULL_TREE; 3012 } 3013 3014 /* Identify whether this is a parameter pack or not. */ 3015 switch (TREE_CODE (t)) 3016 { 3017 case TEMPLATE_PARM_INDEX: 3018 if (TEMPLATE_PARM_PARAMETER_PACK (t)) 3019 parameter_pack_p = true; 3020 break; 3021 3022 case TEMPLATE_TYPE_PARM: 3023 t = TYPE_MAIN_VARIANT (t); 3024 case TEMPLATE_TEMPLATE_PARM: 3025 if (TEMPLATE_TYPE_PARAMETER_PACK (t)) 3026 parameter_pack_p = true; 3027 break; 3028 3029 case PARM_DECL: 3030 if (FUNCTION_PARAMETER_PACK_P (t)) 3031 { 3032 /* We don't want to walk into the type of a PARM_DECL, 3033 because we don't want to see the type parameter pack. */ 3034 *walk_subtrees = 0; 3035 parameter_pack_p = true; 3036 } 3037 break; 3038 3039 case BASES: 3040 parameter_pack_p = true; 3041 break; 3042 default: 3043 /* Not a parameter pack. */ 3044 break; 3045 } 3046 3047 if (parameter_pack_p) 3048 { 3049 /* Add this parameter pack to the list. */ 3050 *ppd->parameter_packs = tree_cons (NULL_TREE, t, *ppd->parameter_packs); 3051 } 3052 3053 if (TYPE_P (t)) 3054 cp_walk_tree (&TYPE_CONTEXT (t), 3055 &find_parameter_packs_r, ppd, ppd->visited); 3056 3057 /* This switch statement will return immediately if we don't find a 3058 parameter pack. */ 3059 switch (TREE_CODE (t)) 3060 { 3061 case TEMPLATE_PARM_INDEX: 3062 return NULL_TREE; 3063 3064 case BOUND_TEMPLATE_TEMPLATE_PARM: 3065 /* Check the template itself. */ 3066 cp_walk_tree (&TREE_TYPE (TYPE_TI_TEMPLATE (t)), 3067 &find_parameter_packs_r, ppd, ppd->visited); 3068 /* Check the template arguments. */ 3069 cp_walk_tree (&TYPE_TI_ARGS (t), &find_parameter_packs_r, ppd, 3070 ppd->visited); 3071 *walk_subtrees = 0; 3072 return NULL_TREE; 3073 3074 case TEMPLATE_TYPE_PARM: 3075 case TEMPLATE_TEMPLATE_PARM: 3076 return NULL_TREE; 3077 3078 case PARM_DECL: 3079 return NULL_TREE; 3080 3081 case RECORD_TYPE: 3082 if (TYPE_PTRMEMFUNC_P (t)) 3083 return NULL_TREE; 3084 /* Fall through. */ 3085 3086 case UNION_TYPE: 3087 case ENUMERAL_TYPE: 3088 if (TYPE_TEMPLATE_INFO (t)) 3089 cp_walk_tree (&TI_ARGS (TYPE_TEMPLATE_INFO (t)), 3090 &find_parameter_packs_r, ppd, ppd->visited); 3091 3092 *walk_subtrees = 0; 3093 return NULL_TREE; 3094 3095 case CONSTRUCTOR: 3096 case TEMPLATE_DECL: 3097 cp_walk_tree (&TREE_TYPE (t), 3098 &find_parameter_packs_r, ppd, ppd->visited); 3099 return NULL_TREE; 3100 3101 case TYPENAME_TYPE: 3102 cp_walk_tree (&TYPENAME_TYPE_FULLNAME (t), &find_parameter_packs_r, 3103 ppd, ppd->visited); 3104 *walk_subtrees = 0; 3105 return NULL_TREE; 3106 3107 case TYPE_PACK_EXPANSION: 3108 case EXPR_PACK_EXPANSION: 3109 *walk_subtrees = 0; 3110 return NULL_TREE; 3111 3112 case INTEGER_TYPE: 3113 cp_walk_tree (&TYPE_MAX_VALUE (t), &find_parameter_packs_r, 3114 ppd, ppd->visited); 3115 *walk_subtrees = 0; 3116 return NULL_TREE; 3117 3118 case IDENTIFIER_NODE: 3119 cp_walk_tree (&TREE_TYPE (t), &find_parameter_packs_r, ppd, 3120 ppd->visited); 3121 *walk_subtrees = 0; 3122 return NULL_TREE; 3123 3124 default: 3125 return NULL_TREE; 3126 } 3127 3128 return NULL_TREE; 3129 } 3130 3131 /* Determines if the expression or type T uses any parameter packs. */ 3132 bool 3133 uses_parameter_packs (tree t) 3134 { 3135 tree parameter_packs = NULL_TREE; 3136 struct find_parameter_pack_data ppd; 3137 ppd.parameter_packs = ¶meter_packs; 3138 ppd.visited = pointer_set_create (); 3139 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited); 3140 pointer_set_destroy (ppd.visited); 3141 return parameter_packs != NULL_TREE; 3142 } 3143 3144 /* Turn ARG, which may be an expression, type, or a TREE_LIST 3145 representation a base-class initializer into a parameter pack 3146 expansion. If all goes well, the resulting node will be an 3147 EXPR_PACK_EXPANSION, TYPE_PACK_EXPANSION, or TREE_LIST, 3148 respectively. */ 3149 tree 3150 make_pack_expansion (tree arg) 3151 { 3152 tree result; 3153 tree parameter_packs = NULL_TREE; 3154 bool for_types = false; 3155 struct find_parameter_pack_data ppd; 3156 3157 if (!arg || arg == error_mark_node) 3158 return arg; 3159 3160 if (TREE_CODE (arg) == TREE_LIST) 3161 { 3162 /* The only time we will see a TREE_LIST here is for a base 3163 class initializer. In this case, the TREE_PURPOSE will be a 3164 _TYPE node (representing the base class expansion we're 3165 initializing) and the TREE_VALUE will be a TREE_LIST 3166 containing the initialization arguments. 3167 3168 The resulting expansion looks somewhat different from most 3169 expansions. Rather than returning just one _EXPANSION, we 3170 return a TREE_LIST whose TREE_PURPOSE is a 3171 TYPE_PACK_EXPANSION containing the bases that will be 3172 initialized. The TREE_VALUE will be identical to the 3173 original TREE_VALUE, which is a list of arguments that will 3174 be passed to each base. We do not introduce any new pack 3175 expansion nodes into the TREE_VALUE (although it is possible 3176 that some already exist), because the TREE_PURPOSE and 3177 TREE_VALUE all need to be expanded together with the same 3178 _EXPANSION node. Note that the TYPE_PACK_EXPANSION in the 3179 resulting TREE_PURPOSE will mention the parameter packs in 3180 both the bases and the arguments to the bases. */ 3181 tree purpose; 3182 tree value; 3183 tree parameter_packs = NULL_TREE; 3184 3185 /* Determine which parameter packs will be used by the base 3186 class expansion. */ 3187 ppd.visited = pointer_set_create (); 3188 ppd.parameter_packs = ¶meter_packs; 3189 cp_walk_tree (&TREE_PURPOSE (arg), &find_parameter_packs_r, 3190 &ppd, ppd.visited); 3191 3192 if (parameter_packs == NULL_TREE) 3193 { 3194 error ("base initializer expansion %<%T%> contains no parameter packs", arg); 3195 pointer_set_destroy (ppd.visited); 3196 return error_mark_node; 3197 } 3198 3199 if (TREE_VALUE (arg) != void_type_node) 3200 { 3201 /* Collect the sets of parameter packs used in each of the 3202 initialization arguments. */ 3203 for (value = TREE_VALUE (arg); value; value = TREE_CHAIN (value)) 3204 { 3205 /* Determine which parameter packs will be expanded in this 3206 argument. */ 3207 cp_walk_tree (&TREE_VALUE (value), &find_parameter_packs_r, 3208 &ppd, ppd.visited); 3209 } 3210 } 3211 3212 pointer_set_destroy (ppd.visited); 3213 3214 /* Create the pack expansion type for the base type. */ 3215 purpose = cxx_make_type (TYPE_PACK_EXPANSION); 3216 SET_PACK_EXPANSION_PATTERN (purpose, TREE_PURPOSE (arg)); 3217 PACK_EXPANSION_PARAMETER_PACKS (purpose) = parameter_packs; 3218 3219 /* Just use structural equality for these TYPE_PACK_EXPANSIONS; 3220 they will rarely be compared to anything. */ 3221 SET_TYPE_STRUCTURAL_EQUALITY (purpose); 3222 3223 return tree_cons (purpose, TREE_VALUE (arg), NULL_TREE); 3224 } 3225 3226 if (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL) 3227 for_types = true; 3228 3229 /* Build the PACK_EXPANSION_* node. */ 3230 result = for_types 3231 ? cxx_make_type (TYPE_PACK_EXPANSION) 3232 : make_node (EXPR_PACK_EXPANSION); 3233 SET_PACK_EXPANSION_PATTERN (result, arg); 3234 if (TREE_CODE (result) == EXPR_PACK_EXPANSION) 3235 { 3236 /* Propagate type and const-expression information. */ 3237 TREE_TYPE (result) = TREE_TYPE (arg); 3238 TREE_CONSTANT (result) = TREE_CONSTANT (arg); 3239 } 3240 else 3241 /* Just use structural equality for these TYPE_PACK_EXPANSIONS; 3242 they will rarely be compared to anything. */ 3243 SET_TYPE_STRUCTURAL_EQUALITY (result); 3244 3245 /* Determine which parameter packs will be expanded. */ 3246 ppd.parameter_packs = ¶meter_packs; 3247 ppd.visited = pointer_set_create (); 3248 cp_walk_tree (&arg, &find_parameter_packs_r, &ppd, ppd.visited); 3249 pointer_set_destroy (ppd.visited); 3250 3251 /* Make sure we found some parameter packs. */ 3252 if (parameter_packs == NULL_TREE) 3253 { 3254 if (TYPE_P (arg)) 3255 error ("expansion pattern %<%T%> contains no argument packs", arg); 3256 else 3257 error ("expansion pattern %<%E%> contains no argument packs", arg); 3258 return error_mark_node; 3259 } 3260 PACK_EXPANSION_PARAMETER_PACKS (result) = parameter_packs; 3261 3262 PACK_EXPANSION_LOCAL_P (result) = at_function_scope_p (); 3263 3264 return result; 3265 } 3266 3267 /* Checks T for any "bare" parameter packs, which have not yet been 3268 expanded, and issues an error if any are found. This operation can 3269 only be done on full expressions or types (e.g., an expression 3270 statement, "if" condition, etc.), because we could have expressions like: 3271 3272 foo(f(g(h(args)))...) 3273 3274 where "args" is a parameter pack. check_for_bare_parameter_packs 3275 should not be called for the subexpressions args, h(args), 3276 g(h(args)), or f(g(h(args))), because we would produce erroneous 3277 error messages. 3278 3279 Returns TRUE and emits an error if there were bare parameter packs, 3280 returns FALSE otherwise. */ 3281 bool 3282 check_for_bare_parameter_packs (tree t) 3283 { 3284 tree parameter_packs = NULL_TREE; 3285 struct find_parameter_pack_data ppd; 3286 3287 if (!processing_template_decl || !t || t == error_mark_node) 3288 return false; 3289 3290 if (TREE_CODE (t) == TYPE_DECL) 3291 t = TREE_TYPE (t); 3292 3293 ppd.parameter_packs = ¶meter_packs; 3294 ppd.visited = pointer_set_create (); 3295 cp_walk_tree (&t, &find_parameter_packs_r, &ppd, ppd.visited); 3296 pointer_set_destroy (ppd.visited); 3297 3298 if (parameter_packs) 3299 { 3300 error ("parameter packs not expanded with %<...%>:"); 3301 while (parameter_packs) 3302 { 3303 tree pack = TREE_VALUE (parameter_packs); 3304 tree name = NULL_TREE; 3305 3306 if (TREE_CODE (pack) == TEMPLATE_TYPE_PARM 3307 || TREE_CODE (pack) == TEMPLATE_TEMPLATE_PARM) 3308 name = TYPE_NAME (pack); 3309 else if (TREE_CODE (pack) == TEMPLATE_PARM_INDEX) 3310 name = DECL_NAME (TEMPLATE_PARM_DECL (pack)); 3311 else 3312 name = DECL_NAME (pack); 3313 3314 if (name) 3315 inform (input_location, " %qD", name); 3316 else 3317 inform (input_location, " <anonymous>"); 3318 3319 parameter_packs = TREE_CHAIN (parameter_packs); 3320 } 3321 3322 return true; 3323 } 3324 3325 return false; 3326 } 3327 3328 /* Expand any parameter packs that occur in the template arguments in 3329 ARGS. */ 3330 tree 3331 expand_template_argument_pack (tree args) 3332 { 3333 tree result_args = NULL_TREE; 3334 int in_arg, out_arg = 0, nargs = args ? TREE_VEC_LENGTH (args) : 0; 3335 int num_result_args = -1; 3336 int non_default_args_count = -1; 3337 3338 /* First, determine if we need to expand anything, and the number of 3339 slots we'll need. */ 3340 for (in_arg = 0; in_arg < nargs; ++in_arg) 3341 { 3342 tree arg = TREE_VEC_ELT (args, in_arg); 3343 if (arg == NULL_TREE) 3344 return args; 3345 if (ARGUMENT_PACK_P (arg)) 3346 { 3347 int num_packed = TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg)); 3348 if (num_result_args < 0) 3349 num_result_args = in_arg + num_packed; 3350 else 3351 num_result_args += num_packed; 3352 } 3353 else 3354 { 3355 if (num_result_args >= 0) 3356 num_result_args++; 3357 } 3358 } 3359 3360 /* If no expansion is necessary, we're done. */ 3361 if (num_result_args < 0) 3362 return args; 3363 3364 /* Expand arguments. */ 3365 result_args = make_tree_vec (num_result_args); 3366 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (args)) 3367 non_default_args_count = 3368 GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (args); 3369 for (in_arg = 0; in_arg < nargs; ++in_arg) 3370 { 3371 tree arg = TREE_VEC_ELT (args, in_arg); 3372 if (ARGUMENT_PACK_P (arg)) 3373 { 3374 tree packed = ARGUMENT_PACK_ARGS (arg); 3375 int i, num_packed = TREE_VEC_LENGTH (packed); 3376 for (i = 0; i < num_packed; ++i, ++out_arg) 3377 TREE_VEC_ELT (result_args, out_arg) = TREE_VEC_ELT(packed, i); 3378 if (non_default_args_count > 0) 3379 non_default_args_count += num_packed; 3380 } 3381 else 3382 { 3383 TREE_VEC_ELT (result_args, out_arg) = arg; 3384 ++out_arg; 3385 } 3386 } 3387 if (non_default_args_count >= 0) 3388 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (result_args, non_default_args_count); 3389 return result_args; 3390 } 3391 3392 /* Checks if DECL shadows a template parameter. 3393 3394 [temp.local]: A template-parameter shall not be redeclared within its 3395 scope (including nested scopes). 3396 3397 Emits an error and returns TRUE if the DECL shadows a parameter, 3398 returns FALSE otherwise. */ 3399 3400 bool 3401 check_template_shadow (tree decl) 3402 { 3403 tree olddecl; 3404 3405 /* If we're not in a template, we can't possibly shadow a template 3406 parameter. */ 3407 if (!current_template_parms) 3408 return true; 3409 3410 /* Figure out what we're shadowing. */ 3411 if (TREE_CODE (decl) == OVERLOAD) 3412 decl = OVL_CURRENT (decl); 3413 olddecl = innermost_non_namespace_value (DECL_NAME (decl)); 3414 3415 /* If there's no previous binding for this name, we're not shadowing 3416 anything, let alone a template parameter. */ 3417 if (!olddecl) 3418 return true; 3419 3420 /* If we're not shadowing a template parameter, we're done. Note 3421 that OLDDECL might be an OVERLOAD (or perhaps even an 3422 ERROR_MARK), so we can't just blithely assume it to be a _DECL 3423 node. */ 3424 if (!DECL_P (olddecl) || !DECL_TEMPLATE_PARM_P (olddecl)) 3425 return true; 3426 3427 /* We check for decl != olddecl to avoid bogus errors for using a 3428 name inside a class. We check TPFI to avoid duplicate errors for 3429 inline member templates. */ 3430 if (decl == olddecl 3431 || TEMPLATE_PARMS_FOR_INLINE (current_template_parms)) 3432 return true; 3433 3434 error ("declaration of %q+#D", decl); 3435 error (" shadows template parm %q+#D", olddecl); 3436 return false; 3437 } 3438 3439 /* Return a new TEMPLATE_PARM_INDEX with the indicated INDEX, LEVEL, 3440 ORIG_LEVEL, DECL, and TYPE. */ 3441 3442 static tree 3443 build_template_parm_index (int index, 3444 int level, 3445 int orig_level, 3446 tree decl, 3447 tree type) 3448 { 3449 tree t = make_node (TEMPLATE_PARM_INDEX); 3450 TEMPLATE_PARM_IDX (t) = index; 3451 TEMPLATE_PARM_LEVEL (t) = level; 3452 TEMPLATE_PARM_ORIG_LEVEL (t) = orig_level; 3453 TEMPLATE_PARM_DECL (t) = decl; 3454 TREE_TYPE (t) = type; 3455 TREE_CONSTANT (t) = TREE_CONSTANT (decl); 3456 TREE_READONLY (t) = TREE_READONLY (decl); 3457 3458 return t; 3459 } 3460 3461 /* Find the canonical type parameter for the given template type 3462 parameter. Returns the canonical type parameter, which may be TYPE 3463 if no such parameter existed. */ 3464 3465 static tree 3466 canonical_type_parameter (tree type) 3467 { 3468 tree list; 3469 int idx = TEMPLATE_TYPE_IDX (type); 3470 if (!canonical_template_parms) 3471 canonical_template_parms = VEC_alloc (tree, gc, idx+1); 3472 3473 while (VEC_length (tree, canonical_template_parms) <= (unsigned)idx) 3474 VEC_safe_push (tree, gc, canonical_template_parms, NULL_TREE); 3475 3476 list = VEC_index (tree, canonical_template_parms, idx); 3477 while (list && !comptypes (type, TREE_VALUE (list), COMPARE_STRUCTURAL)) 3478 list = TREE_CHAIN (list); 3479 3480 if (list) 3481 return TREE_VALUE (list); 3482 else 3483 { 3484 VEC_replace(tree, canonical_template_parms, idx, 3485 tree_cons (NULL_TREE, type, 3486 VEC_index (tree, canonical_template_parms, idx))); 3487 return type; 3488 } 3489 } 3490 3491 /* Return a TEMPLATE_PARM_INDEX, similar to INDEX, but whose 3492 TEMPLATE_PARM_LEVEL has been decreased by LEVELS. If such a 3493 TEMPLATE_PARM_INDEX already exists, it is returned; otherwise, a 3494 new one is created. */ 3495 3496 static tree 3497 reduce_template_parm_level (tree index, tree type, int levels, tree args, 3498 tsubst_flags_t complain) 3499 { 3500 if (TEMPLATE_PARM_DESCENDANTS (index) == NULL_TREE 3501 || (TEMPLATE_PARM_LEVEL (TEMPLATE_PARM_DESCENDANTS (index)) 3502 != TEMPLATE_PARM_LEVEL (index) - levels) 3503 || !same_type_p (type, TREE_TYPE (TEMPLATE_PARM_DESCENDANTS (index)))) 3504 { 3505 tree orig_decl = TEMPLATE_PARM_DECL (index); 3506 tree decl, t; 3507 3508 decl = build_decl (DECL_SOURCE_LOCATION (orig_decl), 3509 TREE_CODE (orig_decl), DECL_NAME (orig_decl), type); 3510 TREE_CONSTANT (decl) = TREE_CONSTANT (orig_decl); 3511 TREE_READONLY (decl) = TREE_READONLY (orig_decl); 3512 DECL_ARTIFICIAL (decl) = 1; 3513 SET_DECL_TEMPLATE_PARM_P (decl); 3514 3515 t = build_template_parm_index (TEMPLATE_PARM_IDX (index), 3516 TEMPLATE_PARM_LEVEL (index) - levels, 3517 TEMPLATE_PARM_ORIG_LEVEL (index), 3518 decl, type); 3519 TEMPLATE_PARM_DESCENDANTS (index) = t; 3520 TEMPLATE_PARM_PARAMETER_PACK (t) 3521 = TEMPLATE_PARM_PARAMETER_PACK (index); 3522 3523 /* Template template parameters need this. */ 3524 if (TREE_CODE (decl) == TEMPLATE_DECL) 3525 DECL_TEMPLATE_PARMS (decl) = tsubst_template_parms 3526 (DECL_TEMPLATE_PARMS (TEMPLATE_PARM_DECL (index)), 3527 args, complain); 3528 } 3529 3530 return TEMPLATE_PARM_DESCENDANTS (index); 3531 } 3532 3533 /* Process information from new template parameter PARM and append it 3534 to the LIST being built. This new parameter is a non-type 3535 parameter iff IS_NON_TYPE is true. This new parameter is a 3536 parameter pack iff IS_PARAMETER_PACK is true. The location of PARM 3537 is in PARM_LOC. NUM_TEMPLATE_PARMS is the size of the template 3538 parameter list PARM belongs to. This is used used to create a 3539 proper canonical type for the type of PARM that is to be created, 3540 iff PARM is a type. If the size is not known, this parameter shall 3541 be set to 0. */ 3542 3543 tree 3544 process_template_parm (tree list, location_t parm_loc, tree parm, 3545 bool is_non_type, bool is_parameter_pack) 3546 { 3547 tree decl = 0; 3548 tree defval; 3549 tree err_parm_list; 3550 int idx = 0; 3551 3552 gcc_assert (TREE_CODE (parm) == TREE_LIST); 3553 defval = TREE_PURPOSE (parm); 3554 3555 if (list) 3556 { 3557 tree p = tree_last (list); 3558 3559 if (p && TREE_VALUE (p) != error_mark_node) 3560 { 3561 p = TREE_VALUE (p); 3562 if (TREE_CODE (p) == TYPE_DECL || TREE_CODE (p) == TEMPLATE_DECL) 3563 idx = TEMPLATE_TYPE_IDX (TREE_TYPE (p)); 3564 else 3565 idx = TEMPLATE_PARM_IDX (DECL_INITIAL (p)); 3566 } 3567 3568 ++idx; 3569 } 3570 else 3571 idx = 0; 3572 3573 if (is_non_type) 3574 { 3575 parm = TREE_VALUE (parm); 3576 3577 SET_DECL_TEMPLATE_PARM_P (parm); 3578 3579 if (TREE_TYPE (parm) == error_mark_node) 3580 { 3581 err_parm_list = build_tree_list (defval, parm); 3582 TREE_VALUE (err_parm_list) = error_mark_node; 3583 return chainon (list, err_parm_list); 3584 } 3585 else 3586 { 3587 /* [temp.param] 3588 3589 The top-level cv-qualifiers on the template-parameter are 3590 ignored when determining its type. */ 3591 TREE_TYPE (parm) = TYPE_MAIN_VARIANT (TREE_TYPE (parm)); 3592 if (invalid_nontype_parm_type_p (TREE_TYPE (parm), 1)) 3593 { 3594 err_parm_list = build_tree_list (defval, parm); 3595 TREE_VALUE (err_parm_list) = error_mark_node; 3596 return chainon (list, err_parm_list); 3597 } 3598 3599 if (uses_parameter_packs (TREE_TYPE (parm)) && !is_parameter_pack) 3600 { 3601 /* This template parameter is not a parameter pack, but it 3602 should be. Complain about "bare" parameter packs. */ 3603 check_for_bare_parameter_packs (TREE_TYPE (parm)); 3604 3605 /* Recover by calling this a parameter pack. */ 3606 is_parameter_pack = true; 3607 } 3608 } 3609 3610 /* A template parameter is not modifiable. */ 3611 TREE_CONSTANT (parm) = 1; 3612 TREE_READONLY (parm) = 1; 3613 decl = build_decl (parm_loc, 3614 CONST_DECL, DECL_NAME (parm), TREE_TYPE (parm)); 3615 TREE_CONSTANT (decl) = 1; 3616 TREE_READONLY (decl) = 1; 3617 DECL_INITIAL (parm) = DECL_INITIAL (decl) 3618 = build_template_parm_index (idx, processing_template_decl, 3619 processing_template_decl, 3620 decl, TREE_TYPE (parm)); 3621 3622 TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm)) 3623 = is_parameter_pack; 3624 } 3625 else 3626 { 3627 tree t; 3628 parm = TREE_VALUE (TREE_VALUE (parm)); 3629 3630 if (parm && TREE_CODE (parm) == TEMPLATE_DECL) 3631 { 3632 t = cxx_make_type (TEMPLATE_TEMPLATE_PARM); 3633 /* This is for distinguishing between real templates and template 3634 template parameters */ 3635 TREE_TYPE (parm) = t; 3636 TREE_TYPE (DECL_TEMPLATE_RESULT (parm)) = t; 3637 decl = parm; 3638 } 3639 else 3640 { 3641 t = cxx_make_type (TEMPLATE_TYPE_PARM); 3642 /* parm is either IDENTIFIER_NODE or NULL_TREE. */ 3643 decl = build_decl (parm_loc, 3644 TYPE_DECL, parm, t); 3645 } 3646 3647 TYPE_NAME (t) = decl; 3648 TYPE_STUB_DECL (t) = decl; 3649 parm = decl; 3650 TEMPLATE_TYPE_PARM_INDEX (t) 3651 = build_template_parm_index (idx, processing_template_decl, 3652 processing_template_decl, 3653 decl, TREE_TYPE (parm)); 3654 TEMPLATE_TYPE_PARAMETER_PACK (t) = is_parameter_pack; 3655 TYPE_CANONICAL (t) = canonical_type_parameter (t); 3656 } 3657 DECL_ARTIFICIAL (decl) = 1; 3658 SET_DECL_TEMPLATE_PARM_P (decl); 3659 pushdecl (decl); 3660 parm = build_tree_list (defval, parm); 3661 return chainon (list, parm); 3662 } 3663 3664 /* The end of a template parameter list has been reached. Process the 3665 tree list into a parameter vector, converting each parameter into a more 3666 useful form. Type parameters are saved as IDENTIFIER_NODEs, and others 3667 as PARM_DECLs. */ 3668 3669 tree 3670 end_template_parm_list (tree parms) 3671 { 3672 int nparms; 3673 tree parm, next; 3674 tree saved_parmlist = make_tree_vec (list_length (parms)); 3675 3676 current_template_parms 3677 = tree_cons (size_int (processing_template_decl), 3678 saved_parmlist, current_template_parms); 3679 3680 for (parm = parms, nparms = 0; parm; parm = next, nparms++) 3681 { 3682 next = TREE_CHAIN (parm); 3683 TREE_VEC_ELT (saved_parmlist, nparms) = parm; 3684 TREE_CHAIN (parm) = NULL_TREE; 3685 } 3686 3687 --processing_template_parmlist; 3688 3689 return saved_parmlist; 3690 } 3691 3692 /* end_template_decl is called after a template declaration is seen. */ 3693 3694 void 3695 end_template_decl (void) 3696 { 3697 reset_specialization (); 3698 3699 if (! processing_template_decl) 3700 return; 3701 3702 /* This matches the pushlevel in begin_template_parm_list. */ 3703 finish_scope (); 3704 3705 --processing_template_decl; 3706 current_template_parms = TREE_CHAIN (current_template_parms); 3707 } 3708 3709 /* Takes a TREE_LIST representing a template parameter and convert it 3710 into an argument suitable to be passed to the type substitution 3711 functions. Note that If the TREE_LIST contains an error_mark 3712 node, the returned argument is error_mark_node. */ 3713 3714 static tree 3715 template_parm_to_arg (tree t) 3716 { 3717 3718 if (t == NULL_TREE 3719 || TREE_CODE (t) != TREE_LIST) 3720 return t; 3721 3722 if (error_operand_p (TREE_VALUE (t))) 3723 return error_mark_node; 3724 3725 t = TREE_VALUE (t); 3726 3727 if (TREE_CODE (t) == TYPE_DECL 3728 || TREE_CODE (t) == TEMPLATE_DECL) 3729 { 3730 t = TREE_TYPE (t); 3731 3732 if (TEMPLATE_TYPE_PARAMETER_PACK (t)) 3733 { 3734 /* Turn this argument into a TYPE_ARGUMENT_PACK 3735 with a single element, which expands T. */ 3736 tree vec = make_tree_vec (1); 3737 #ifdef ENABLE_CHECKING 3738 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT 3739 (vec, TREE_VEC_LENGTH (vec)); 3740 #endif 3741 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t); 3742 3743 t = cxx_make_type (TYPE_ARGUMENT_PACK); 3744 SET_ARGUMENT_PACK_ARGS (t, vec); 3745 } 3746 } 3747 else 3748 { 3749 t = DECL_INITIAL (t); 3750 3751 if (TEMPLATE_PARM_PARAMETER_PACK (t)) 3752 { 3753 /* Turn this argument into a NONTYPE_ARGUMENT_PACK 3754 with a single element, which expands T. */ 3755 tree vec = make_tree_vec (1); 3756 tree type = TREE_TYPE (TEMPLATE_PARM_DECL (t)); 3757 #ifdef ENABLE_CHECKING 3758 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT 3759 (vec, TREE_VEC_LENGTH (vec)); 3760 #endif 3761 TREE_VEC_ELT (vec, 0) = make_pack_expansion (t); 3762 3763 t = make_node (NONTYPE_ARGUMENT_PACK); 3764 SET_ARGUMENT_PACK_ARGS (t, vec); 3765 TREE_TYPE (t) = type; 3766 } 3767 } 3768 return t; 3769 } 3770 3771 /* This function returns TRUE if PARM_PACK is a template parameter 3772 pack and if ARG_PACK is what template_parm_to_arg returned when 3773 passed PARM_PACK. */ 3774 3775 static bool 3776 arg_from_parm_pack_p (tree arg_pack, tree parm_pack) 3777 { 3778 /* For clarity in the comments below let's use the representation 3779 argument_pack<elements>' to denote an argument pack and its 3780 elements. 3781 3782 In the 'if' block below, we want to detect cases where 3783 ARG_PACK is argument_pack<PARM_PACK...>. I.e, we want to 3784 check if ARG_PACK is an argument pack which sole element is 3785 the expansion of PARM_PACK. That argument pack is typically 3786 created by template_parm_to_arg when passed a parameter 3787 pack. */ 3788 3789 if (arg_pack 3790 && TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1 3791 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0))) 3792 { 3793 tree expansion = TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 0); 3794 tree pattern = PACK_EXPANSION_PATTERN (expansion); 3795 if ((TYPE_P (pattern) && same_type_p (pattern, parm_pack)) 3796 || (!TYPE_P (pattern) && cp_tree_equal (parm_pack, pattern))) 3797 /* The argument pack that the parameter maps to is just an 3798 expansion of the parameter itself, such as one would 3799 find in the implicit typedef of a class inside the 3800 class itself. Consider this parameter "unsubstituted", 3801 so that we will maintain the outer pack expansion. */ 3802 return true; 3803 } 3804 return false; 3805 } 3806 3807 /* Within the declaration of a template, return all levels of template 3808 parameters that apply. The template parameters are represented as 3809 a TREE_VEC, in the form documented in cp-tree.h for template 3810 arguments. */ 3811 3812 static tree 3813 current_template_args (void) 3814 { 3815 tree header; 3816 tree args = NULL_TREE; 3817 int length = TMPL_PARMS_DEPTH (current_template_parms); 3818 int l = length; 3819 3820 /* If there is only one level of template parameters, we do not 3821 create a TREE_VEC of TREE_VECs. Instead, we return a single 3822 TREE_VEC containing the arguments. */ 3823 if (length > 1) 3824 args = make_tree_vec (length); 3825 3826 for (header = current_template_parms; header; header = TREE_CHAIN (header)) 3827 { 3828 tree a = copy_node (TREE_VALUE (header)); 3829 int i; 3830 3831 TREE_TYPE (a) = NULL_TREE; 3832 for (i = TREE_VEC_LENGTH (a) - 1; i >= 0; --i) 3833 TREE_VEC_ELT (a, i) = template_parm_to_arg (TREE_VEC_ELT (a, i)); 3834 3835 #ifdef ENABLE_CHECKING 3836 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (a, TREE_VEC_LENGTH (a)); 3837 #endif 3838 3839 if (length > 1) 3840 TREE_VEC_ELT (args, --l) = a; 3841 else 3842 args = a; 3843 } 3844 3845 if (length > 1 && TREE_VEC_ELT (args, 0) == NULL_TREE) 3846 /* This can happen for template parms of a template template 3847 parameter, e.g: 3848 3849 template<template<class T, class U> class TT> struct S; 3850 3851 Consider the level of the parms of TT; T and U both have 3852 level 2; TT has no template parm of level 1. So in this case 3853 the first element of full_template_args is NULL_TREE. If we 3854 leave it like this TMPL_ARG_DEPTH on args returns 1 instead 3855 of 2. This will make tsubst wrongly consider that T and U 3856 have level 1. Instead, let's create a dummy vector as the 3857 first element of full_template_args so that TMPL_ARG_DEPTH 3858 returns the correct depth for args. */ 3859 TREE_VEC_ELT (args, 0) = make_tree_vec (1); 3860 return args; 3861 } 3862 3863 /* Update the declared TYPE by doing any lookups which were thought to be 3864 dependent, but are not now that we know the SCOPE of the declarator. */ 3865 3866 tree 3867 maybe_update_decl_type (tree orig_type, tree scope) 3868 { 3869 tree type = orig_type; 3870 3871 if (type == NULL_TREE) 3872 return type; 3873 3874 if (TREE_CODE (orig_type) == TYPE_DECL) 3875 type = TREE_TYPE (type); 3876 3877 if (scope && TYPE_P (scope) && dependent_type_p (scope) 3878 && dependent_type_p (type) 3879 /* Don't bother building up the args in this case. */ 3880 && TREE_CODE (type) != TEMPLATE_TYPE_PARM) 3881 { 3882 /* tsubst in the args corresponding to the template parameters, 3883 including auto if present. Most things will be unchanged, but 3884 make_typename_type and tsubst_qualified_id will resolve 3885 TYPENAME_TYPEs and SCOPE_REFs that were previously dependent. */ 3886 tree args = current_template_args (); 3887 tree auto_node = type_uses_auto (type); 3888 tree pushed; 3889 if (auto_node) 3890 { 3891 tree auto_vec = make_tree_vec (1); 3892 TREE_VEC_ELT (auto_vec, 0) = auto_node; 3893 args = add_to_template_args (args, auto_vec); 3894 } 3895 pushed = push_scope (scope); 3896 type = tsubst (type, args, tf_warning_or_error, NULL_TREE); 3897 if (pushed) 3898 pop_scope (scope); 3899 } 3900 3901 if (type == error_mark_node) 3902 return orig_type; 3903 3904 if (TREE_CODE (orig_type) == TYPE_DECL) 3905 { 3906 if (same_type_p (type, TREE_TYPE (orig_type))) 3907 type = orig_type; 3908 else 3909 type = TYPE_NAME (type); 3910 } 3911 return type; 3912 } 3913 3914 /* Return a TEMPLATE_DECL corresponding to DECL, using the indicated 3915 template PARMS. If MEMBER_TEMPLATE_P is true, the new template is 3916 a member template. Used by push_template_decl below. */ 3917 3918 static tree 3919 build_template_decl (tree decl, tree parms, bool member_template_p) 3920 { 3921 tree tmpl = build_lang_decl (TEMPLATE_DECL, DECL_NAME (decl), NULL_TREE); 3922 DECL_TEMPLATE_PARMS (tmpl) = parms; 3923 DECL_CONTEXT (tmpl) = DECL_CONTEXT (decl); 3924 DECL_SOURCE_LOCATION (tmpl) = DECL_SOURCE_LOCATION (decl); 3925 DECL_MEMBER_TEMPLATE_P (tmpl) = member_template_p; 3926 3927 return tmpl; 3928 } 3929 3930 struct template_parm_data 3931 { 3932 /* The level of the template parameters we are currently 3933 processing. */ 3934 int level; 3935 3936 /* The index of the specialization argument we are currently 3937 processing. */ 3938 int current_arg; 3939 3940 /* An array whose size is the number of template parameters. The 3941 elements are nonzero if the parameter has been used in any one 3942 of the arguments processed so far. */ 3943 int* parms; 3944 3945 /* An array whose size is the number of template arguments. The 3946 elements are nonzero if the argument makes use of template 3947 parameters of this level. */ 3948 int* arg_uses_template_parms; 3949 }; 3950 3951 /* Subroutine of push_template_decl used to see if each template 3952 parameter in a partial specialization is used in the explicit 3953 argument list. If T is of the LEVEL given in DATA (which is 3954 treated as a template_parm_data*), then DATA->PARMS is marked 3955 appropriately. */ 3956 3957 static int 3958 mark_template_parm (tree t, void* data) 3959 { 3960 int level; 3961 int idx; 3962 struct template_parm_data* tpd = (struct template_parm_data*) data; 3963 3964 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX) 3965 { 3966 level = TEMPLATE_PARM_LEVEL (t); 3967 idx = TEMPLATE_PARM_IDX (t); 3968 } 3969 else 3970 { 3971 level = TEMPLATE_TYPE_LEVEL (t); 3972 idx = TEMPLATE_TYPE_IDX (t); 3973 } 3974 3975 if (level == tpd->level) 3976 { 3977 tpd->parms[idx] = 1; 3978 tpd->arg_uses_template_parms[tpd->current_arg] = 1; 3979 } 3980 3981 /* Return zero so that for_each_template_parm will continue the 3982 traversal of the tree; we want to mark *every* template parm. */ 3983 return 0; 3984 } 3985 3986 /* Process the partial specialization DECL. */ 3987 3988 static tree 3989 process_partial_specialization (tree decl) 3990 { 3991 tree type = TREE_TYPE (decl); 3992 tree maintmpl = CLASSTYPE_TI_TEMPLATE (type); 3993 tree specargs = CLASSTYPE_TI_ARGS (type); 3994 tree inner_args = INNERMOST_TEMPLATE_ARGS (specargs); 3995 tree main_inner_parms = DECL_INNERMOST_TEMPLATE_PARMS (maintmpl); 3996 tree inner_parms; 3997 tree inst; 3998 int nargs = TREE_VEC_LENGTH (inner_args); 3999 int ntparms; 4000 int i; 4001 bool did_error_intro = false; 4002 struct template_parm_data tpd; 4003 struct template_parm_data tpd2; 4004 4005 gcc_assert (current_template_parms); 4006 4007 inner_parms = INNERMOST_TEMPLATE_PARMS (current_template_parms); 4008 ntparms = TREE_VEC_LENGTH (inner_parms); 4009 4010 /* We check that each of the template parameters given in the 4011 partial specialization is used in the argument list to the 4012 specialization. For example: 4013 4014 template <class T> struct S; 4015 template <class T> struct S<T*>; 4016 4017 The second declaration is OK because `T*' uses the template 4018 parameter T, whereas 4019 4020 template <class T> struct S<int>; 4021 4022 is no good. Even trickier is: 4023 4024 template <class T> 4025 struct S1 4026 { 4027 template <class U> 4028 struct S2; 4029 template <class U> 4030 struct S2<T>; 4031 }; 4032 4033 The S2<T> declaration is actually invalid; it is a 4034 full-specialization. Of course, 4035 4036 template <class U> 4037 struct S2<T (*)(U)>; 4038 4039 or some such would have been OK. */ 4040 tpd.level = TMPL_PARMS_DEPTH (current_template_parms); 4041 tpd.parms = XALLOCAVEC (int, ntparms); 4042 memset (tpd.parms, 0, sizeof (int) * ntparms); 4043 4044 tpd.arg_uses_template_parms = XALLOCAVEC (int, nargs); 4045 memset (tpd.arg_uses_template_parms, 0, sizeof (int) * nargs); 4046 for (i = 0; i < nargs; ++i) 4047 { 4048 tpd.current_arg = i; 4049 for_each_template_parm (TREE_VEC_ELT (inner_args, i), 4050 &mark_template_parm, 4051 &tpd, 4052 NULL, 4053 /*include_nondeduced_p=*/false); 4054 } 4055 for (i = 0; i < ntparms; ++i) 4056 if (tpd.parms[i] == 0) 4057 { 4058 /* One of the template parms was not used in the 4059 specialization. */ 4060 if (!did_error_intro) 4061 { 4062 error ("template parameters not used in partial specialization:"); 4063 did_error_intro = true; 4064 } 4065 4066 error (" %qD", TREE_VALUE (TREE_VEC_ELT (inner_parms, i))); 4067 } 4068 4069 if (did_error_intro) 4070 return error_mark_node; 4071 4072 /* [temp.class.spec] 4073 4074 The argument list of the specialization shall not be identical to 4075 the implicit argument list of the primary template. */ 4076 if (comp_template_args 4077 (inner_args, 4078 INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE 4079 (maintmpl))))) 4080 error ("partial specialization %qT does not specialize any template arguments", type); 4081 4082 /* [temp.class.spec] 4083 4084 A partially specialized non-type argument expression shall not 4085 involve template parameters of the partial specialization except 4086 when the argument expression is a simple identifier. 4087 4088 The type of a template parameter corresponding to a specialized 4089 non-type argument shall not be dependent on a parameter of the 4090 specialization. 4091 4092 Also, we verify that pack expansions only occur at the 4093 end of the argument list. */ 4094 gcc_assert (nargs == DECL_NTPARMS (maintmpl)); 4095 tpd2.parms = 0; 4096 for (i = 0; i < nargs; ++i) 4097 { 4098 tree parm = TREE_VALUE (TREE_VEC_ELT (main_inner_parms, i)); 4099 tree arg = TREE_VEC_ELT (inner_args, i); 4100 tree packed_args = NULL_TREE; 4101 int j, len = 1; 4102 4103 if (ARGUMENT_PACK_P (arg)) 4104 { 4105 /* Extract the arguments from the argument pack. We'll be 4106 iterating over these in the following loop. */ 4107 packed_args = ARGUMENT_PACK_ARGS (arg); 4108 len = TREE_VEC_LENGTH (packed_args); 4109 } 4110 4111 for (j = 0; j < len; j++) 4112 { 4113 if (packed_args) 4114 /* Get the Jth argument in the parameter pack. */ 4115 arg = TREE_VEC_ELT (packed_args, j); 4116 4117 if (PACK_EXPANSION_P (arg)) 4118 { 4119 /* Pack expansions must come at the end of the 4120 argument list. */ 4121 if ((packed_args && j < len - 1) 4122 || (!packed_args && i < nargs - 1)) 4123 { 4124 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION) 4125 error ("parameter pack argument %qE must be at the " 4126 "end of the template argument list", arg); 4127 else 4128 error ("parameter pack argument %qT must be at the " 4129 "end of the template argument list", arg); 4130 } 4131 } 4132 4133 if (TREE_CODE (arg) == EXPR_PACK_EXPANSION) 4134 /* We only care about the pattern. */ 4135 arg = PACK_EXPANSION_PATTERN (arg); 4136 4137 if (/* These first two lines are the `non-type' bit. */ 4138 !TYPE_P (arg) 4139 && TREE_CODE (arg) != TEMPLATE_DECL 4140 /* This next line is the `argument expression is not just a 4141 simple identifier' condition and also the `specialized 4142 non-type argument' bit. */ 4143 && TREE_CODE (arg) != TEMPLATE_PARM_INDEX) 4144 { 4145 if ((!packed_args && tpd.arg_uses_template_parms[i]) 4146 || (packed_args && uses_template_parms (arg))) 4147 error ("template argument %qE involves template parameter(s)", 4148 arg); 4149 else 4150 { 4151 /* Look at the corresponding template parameter, 4152 marking which template parameters its type depends 4153 upon. */ 4154 tree type = TREE_TYPE (parm); 4155 4156 if (!tpd2.parms) 4157 { 4158 /* We haven't yet initialized TPD2. Do so now. */ 4159 tpd2.arg_uses_template_parms = XALLOCAVEC (int, nargs); 4160 /* The number of parameters here is the number in the 4161 main template, which, as checked in the assertion 4162 above, is NARGS. */ 4163 tpd2.parms = XALLOCAVEC (int, nargs); 4164 tpd2.level = 4165 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (maintmpl)); 4166 } 4167 4168 /* Mark the template parameters. But this time, we're 4169 looking for the template parameters of the main 4170 template, not in the specialization. */ 4171 tpd2.current_arg = i; 4172 tpd2.arg_uses_template_parms[i] = 0; 4173 memset (tpd2.parms, 0, sizeof (int) * nargs); 4174 for_each_template_parm (type, 4175 &mark_template_parm, 4176 &tpd2, 4177 NULL, 4178 /*include_nondeduced_p=*/false); 4179 4180 if (tpd2.arg_uses_template_parms [i]) 4181 { 4182 /* The type depended on some template parameters. 4183 If they are fully specialized in the 4184 specialization, that's OK. */ 4185 int j; 4186 int count = 0; 4187 for (j = 0; j < nargs; ++j) 4188 if (tpd2.parms[j] != 0 4189 && tpd.arg_uses_template_parms [j]) 4190 ++count; 4191 if (count != 0) 4192 error_n (input_location, count, 4193 "type %qT of template argument %qE depends " 4194 "on a template parameter", 4195 "type %qT of template argument %qE depends " 4196 "on template parameters", 4197 type, 4198 arg); 4199 } 4200 } 4201 } 4202 } 4203 } 4204 4205 /* We should only get here once. */ 4206 gcc_assert (!COMPLETE_TYPE_P (type)); 4207 4208 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl) 4209 = tree_cons (specargs, inner_parms, 4210 DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)); 4211 TREE_TYPE (DECL_TEMPLATE_SPECIALIZATIONS (maintmpl)) = type; 4212 4213 for (inst = DECL_TEMPLATE_INSTANTIATIONS (maintmpl); inst; 4214 inst = TREE_CHAIN (inst)) 4215 { 4216 tree inst_type = TREE_VALUE (inst); 4217 if (COMPLETE_TYPE_P (inst_type) 4218 && CLASSTYPE_IMPLICIT_INSTANTIATION (inst_type)) 4219 { 4220 tree spec = most_specialized_class (inst_type, maintmpl, tf_none); 4221 if (spec && TREE_TYPE (spec) == type) 4222 permerror (input_location, 4223 "partial specialization of %qT after instantiation " 4224 "of %qT", type, inst_type); 4225 } 4226 } 4227 4228 return decl; 4229 } 4230 4231 /* Check that a template declaration's use of default arguments and 4232 parameter packs is not invalid. Here, PARMS are the template 4233 parameters. IS_PRIMARY is nonzero if DECL is the thing declared by 4234 a primary template. IS_PARTIAL is nonzero if DECL is a partial 4235 specialization. 4236 4237 4238 IS_FRIEND_DECL is nonzero if DECL is a friend function template 4239 declaration (but not a definition); 1 indicates a declaration, 2 4240 indicates a redeclaration. When IS_FRIEND_DECL=2, no errors are 4241 emitted for extraneous default arguments. 4242 4243 Returns TRUE if there were no errors found, FALSE otherwise. */ 4244 4245 bool 4246 check_default_tmpl_args (tree decl, tree parms, int is_primary, 4247 int is_partial, int is_friend_decl) 4248 { 4249 const char *msg; 4250 int last_level_to_check; 4251 tree parm_level; 4252 bool no_errors = true; 4253 4254 /* [temp.param] 4255 4256 A default template-argument shall not be specified in a 4257 function template declaration or a function template definition, nor 4258 in the template-parameter-list of the definition of a member of a 4259 class template. */ 4260 4261 if (TREE_CODE (CP_DECL_CONTEXT (decl)) == FUNCTION_DECL) 4262 /* You can't have a function template declaration in a local 4263 scope, nor you can you define a member of a class template in a 4264 local scope. */ 4265 return true; 4266 4267 if (current_class_type 4268 && !TYPE_BEING_DEFINED (current_class_type) 4269 && DECL_LANG_SPECIFIC (decl) 4270 && DECL_DECLARES_FUNCTION_P (decl) 4271 /* If this is either a friend defined in the scope of the class 4272 or a member function. */ 4273 && (DECL_FUNCTION_MEMBER_P (decl) 4274 ? same_type_p (DECL_CONTEXT (decl), current_class_type) 4275 : DECL_FRIEND_CONTEXT (decl) 4276 ? same_type_p (DECL_FRIEND_CONTEXT (decl), current_class_type) 4277 : false) 4278 /* And, if it was a member function, it really was defined in 4279 the scope of the class. */ 4280 && (!DECL_FUNCTION_MEMBER_P (decl) 4281 || DECL_INITIALIZED_IN_CLASS_P (decl))) 4282 /* We already checked these parameters when the template was 4283 declared, so there's no need to do it again now. This function 4284 was defined in class scope, but we're processing it's body now 4285 that the class is complete. */ 4286 return true; 4287 4288 /* Core issue 226 (C++0x only): the following only applies to class 4289 templates. */ 4290 if ((cxx_dialect == cxx98) || TREE_CODE (decl) != FUNCTION_DECL) 4291 { 4292 /* [temp.param] 4293 4294 If a template-parameter has a default template-argument, all 4295 subsequent template-parameters shall have a default 4296 template-argument supplied. */ 4297 for (parm_level = parms; parm_level; parm_level = TREE_CHAIN (parm_level)) 4298 { 4299 tree inner_parms = TREE_VALUE (parm_level); 4300 int ntparms = TREE_VEC_LENGTH (inner_parms); 4301 int seen_def_arg_p = 0; 4302 int i; 4303 4304 for (i = 0; i < ntparms; ++i) 4305 { 4306 tree parm = TREE_VEC_ELT (inner_parms, i); 4307 4308 if (parm == error_mark_node) 4309 continue; 4310 4311 if (TREE_PURPOSE (parm)) 4312 seen_def_arg_p = 1; 4313 else if (seen_def_arg_p 4314 && !template_parameter_pack_p (TREE_VALUE (parm))) 4315 { 4316 error ("no default argument for %qD", TREE_VALUE (parm)); 4317 /* For better subsequent error-recovery, we indicate that 4318 there should have been a default argument. */ 4319 TREE_PURPOSE (parm) = error_mark_node; 4320 no_errors = false; 4321 } 4322 else if (is_primary 4323 && !is_partial 4324 && !is_friend_decl 4325 /* Don't complain about an enclosing partial 4326 specialization. */ 4327 && parm_level == parms 4328 && TREE_CODE (decl) == TYPE_DECL 4329 && i < ntparms - 1 4330 && template_parameter_pack_p (TREE_VALUE (parm))) 4331 { 4332 /* A primary class template can only have one 4333 parameter pack, at the end of the template 4334 parameter list. */ 4335 4336 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL) 4337 error ("parameter pack %qE must be at the end of the" 4338 " template parameter list", TREE_VALUE (parm)); 4339 else 4340 error ("parameter pack %qT must be at the end of the" 4341 " template parameter list", 4342 TREE_TYPE (TREE_VALUE (parm))); 4343 4344 TREE_VALUE (TREE_VEC_ELT (inner_parms, i)) 4345 = error_mark_node; 4346 no_errors = false; 4347 } 4348 } 4349 } 4350 } 4351 4352 if (((cxx_dialect == cxx98) && TREE_CODE (decl) != TYPE_DECL) 4353 || is_partial 4354 || !is_primary 4355 || is_friend_decl) 4356 /* For an ordinary class template, default template arguments are 4357 allowed at the innermost level, e.g.: 4358 template <class T = int> 4359 struct S {}; 4360 but, in a partial specialization, they're not allowed even 4361 there, as we have in [temp.class.spec]: 4362 4363 The template parameter list of a specialization shall not 4364 contain default template argument values. 4365 4366 So, for a partial specialization, or for a function template 4367 (in C++98/C++03), we look at all of them. */ 4368 ; 4369 else 4370 /* But, for a primary class template that is not a partial 4371 specialization we look at all template parameters except the 4372 innermost ones. */ 4373 parms = TREE_CHAIN (parms); 4374 4375 /* Figure out what error message to issue. */ 4376 if (is_friend_decl == 2) 4377 msg = G_("default template arguments may not be used in function template " 4378 "friend re-declaration"); 4379 else if (is_friend_decl) 4380 msg = G_("default template arguments may not be used in function template " 4381 "friend declarations"); 4382 else if (TREE_CODE (decl) == FUNCTION_DECL && (cxx_dialect == cxx98)) 4383 msg = G_("default template arguments may not be used in function templates " 4384 "without -std=c++11 or -std=gnu++11"); 4385 else if (is_partial) 4386 msg = G_("default template arguments may not be used in " 4387 "partial specializations"); 4388 else 4389 msg = G_("default argument for template parameter for class enclosing %qD"); 4390 4391 if (current_class_type && TYPE_BEING_DEFINED (current_class_type)) 4392 /* If we're inside a class definition, there's no need to 4393 examine the parameters to the class itself. On the one 4394 hand, they will be checked when the class is defined, and, 4395 on the other, default arguments are valid in things like: 4396 template <class T = double> 4397 struct S { template <class U> void f(U); }; 4398 Here the default argument for `S' has no bearing on the 4399 declaration of `f'. */ 4400 last_level_to_check = template_class_depth (current_class_type) + 1; 4401 else 4402 /* Check everything. */ 4403 last_level_to_check = 0; 4404 4405 for (parm_level = parms; 4406 parm_level && TMPL_PARMS_DEPTH (parm_level) >= last_level_to_check; 4407 parm_level = TREE_CHAIN (parm_level)) 4408 { 4409 tree inner_parms = TREE_VALUE (parm_level); 4410 int i; 4411 int ntparms; 4412 4413 ntparms = TREE_VEC_LENGTH (inner_parms); 4414 for (i = 0; i < ntparms; ++i) 4415 { 4416 if (TREE_VEC_ELT (inner_parms, i) == error_mark_node) 4417 continue; 4418 4419 if (TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i))) 4420 { 4421 if (msg) 4422 { 4423 no_errors = false; 4424 if (is_friend_decl == 2) 4425 return no_errors; 4426 4427 error (msg, decl); 4428 msg = 0; 4429 } 4430 4431 /* Clear out the default argument so that we are not 4432 confused later. */ 4433 TREE_PURPOSE (TREE_VEC_ELT (inner_parms, i)) = NULL_TREE; 4434 } 4435 } 4436 4437 /* At this point, if we're still interested in issuing messages, 4438 they must apply to classes surrounding the object declared. */ 4439 if (msg) 4440 msg = G_("default argument for template parameter for class " 4441 "enclosing %qD"); 4442 } 4443 4444 return no_errors; 4445 } 4446 4447 /* Worker for push_template_decl_real, called via 4448 for_each_template_parm. DATA is really an int, indicating the 4449 level of the parameters we are interested in. If T is a template 4450 parameter of that level, return nonzero. */ 4451 4452 static int 4453 template_parm_this_level_p (tree t, void* data) 4454 { 4455 int this_level = *(int *)data; 4456 int level; 4457 4458 if (TREE_CODE (t) == TEMPLATE_PARM_INDEX) 4459 level = TEMPLATE_PARM_LEVEL (t); 4460 else 4461 level = TEMPLATE_TYPE_LEVEL (t); 4462 return level == this_level; 4463 } 4464 4465 /* Creates a TEMPLATE_DECL for the indicated DECL using the template 4466 parameters given by current_template_args, or reuses a 4467 previously existing one, if appropriate. Returns the DECL, or an 4468 equivalent one, if it is replaced via a call to duplicate_decls. 4469 4470 If IS_FRIEND is true, DECL is a friend declaration. */ 4471 4472 tree 4473 push_template_decl_real (tree decl, bool is_friend) 4474 { 4475 tree tmpl; 4476 tree args; 4477 tree info; 4478 tree ctx; 4479 int primary; 4480 int is_partial; 4481 int new_template_p = 0; 4482 /* True if the template is a member template, in the sense of 4483 [temp.mem]. */ 4484 bool member_template_p = false; 4485 4486 if (decl == error_mark_node || !current_template_parms) 4487 return error_mark_node; 4488 4489 /* See if this is a partial specialization. */ 4490 is_partial = (DECL_IMPLICIT_TYPEDEF_P (decl) 4491 && TREE_CODE (TREE_TYPE (decl)) != ENUMERAL_TYPE 4492 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl))); 4493 4494 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_FRIEND_P (decl)) 4495 is_friend = true; 4496 4497 if (is_friend) 4498 /* For a friend, we want the context of the friend function, not 4499 the type of which it is a friend. */ 4500 ctx = CP_DECL_CONTEXT (decl); 4501 else if (CP_DECL_CONTEXT (decl) 4502 && TREE_CODE (CP_DECL_CONTEXT (decl)) != NAMESPACE_DECL) 4503 /* In the case of a virtual function, we want the class in which 4504 it is defined. */ 4505 ctx = CP_DECL_CONTEXT (decl); 4506 else 4507 /* Otherwise, if we're currently defining some class, the DECL 4508 is assumed to be a member of the class. */ 4509 ctx = current_scope (); 4510 4511 if (ctx && TREE_CODE (ctx) == NAMESPACE_DECL) 4512 ctx = NULL_TREE; 4513 4514 if (!DECL_CONTEXT (decl)) 4515 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace); 4516 4517 /* See if this is a primary template. */ 4518 if (is_friend && ctx) 4519 /* A friend template that specifies a class context, i.e. 4520 template <typename T> friend void A<T>::f(); 4521 is not primary. */ 4522 primary = 0; 4523 else 4524 primary = template_parm_scope_p (); 4525 4526 if (primary) 4527 { 4528 if (DECL_CLASS_SCOPE_P (decl)) 4529 member_template_p = true; 4530 if (TREE_CODE (decl) == TYPE_DECL 4531 && ANON_AGGRNAME_P (DECL_NAME (decl))) 4532 { 4533 error ("template class without a name"); 4534 return error_mark_node; 4535 } 4536 else if (TREE_CODE (decl) == FUNCTION_DECL) 4537 { 4538 if (DECL_DESTRUCTOR_P (decl)) 4539 { 4540 /* [temp.mem] 4541 4542 A destructor shall not be a member template. */ 4543 error ("destructor %qD declared as member template", decl); 4544 return error_mark_node; 4545 } 4546 if (NEW_DELETE_OPNAME_P (DECL_NAME (decl)) 4547 && (!prototype_p (TREE_TYPE (decl)) 4548 || TYPE_ARG_TYPES (TREE_TYPE (decl)) == void_list_node 4549 || !TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (decl))) 4550 || (TREE_CHAIN (TYPE_ARG_TYPES ((TREE_TYPE (decl)))) 4551 == void_list_node))) 4552 { 4553 /* [basic.stc.dynamic.allocation] 4554 4555 An allocation function can be a function 4556 template. ... Template allocation functions shall 4557 have two or more parameters. */ 4558 error ("invalid template declaration of %qD", decl); 4559 return error_mark_node; 4560 } 4561 } 4562 else if (DECL_IMPLICIT_TYPEDEF_P (decl) 4563 && CLASS_TYPE_P (TREE_TYPE (decl))) 4564 /* OK */; 4565 else if (TREE_CODE (decl) == TYPE_DECL 4566 && TYPE_DECL_ALIAS_P (decl)) 4567 /* alias-declaration */ 4568 gcc_assert (!DECL_ARTIFICIAL (decl)); 4569 else 4570 { 4571 error ("template declaration of %q#D", decl); 4572 return error_mark_node; 4573 } 4574 } 4575 4576 /* Check to see that the rules regarding the use of default 4577 arguments are not being violated. */ 4578 check_default_tmpl_args (decl, current_template_parms, 4579 primary, is_partial, /*is_friend_decl=*/0); 4580 4581 /* Ensure that there are no parameter packs in the type of this 4582 declaration that have not been expanded. */ 4583 if (TREE_CODE (decl) == FUNCTION_DECL) 4584 { 4585 /* Check each of the arguments individually to see if there are 4586 any bare parameter packs. */ 4587 tree type = TREE_TYPE (decl); 4588 tree arg = DECL_ARGUMENTS (decl); 4589 tree argtype = TYPE_ARG_TYPES (type); 4590 4591 while (arg && argtype) 4592 { 4593 if (!FUNCTION_PARAMETER_PACK_P (arg) 4594 && check_for_bare_parameter_packs (TREE_TYPE (arg))) 4595 { 4596 /* This is a PARM_DECL that contains unexpanded parameter 4597 packs. We have already complained about this in the 4598 check_for_bare_parameter_packs call, so just replace 4599 these types with ERROR_MARK_NODE. */ 4600 TREE_TYPE (arg) = error_mark_node; 4601 TREE_VALUE (argtype) = error_mark_node; 4602 } 4603 4604 arg = DECL_CHAIN (arg); 4605 argtype = TREE_CHAIN (argtype); 4606 } 4607 4608 /* Check for bare parameter packs in the return type and the 4609 exception specifiers. */ 4610 if (check_for_bare_parameter_packs (TREE_TYPE (type))) 4611 /* Errors were already issued, set return type to int 4612 as the frontend doesn't expect error_mark_node as 4613 the return type. */ 4614 TREE_TYPE (type) = integer_type_node; 4615 if (check_for_bare_parameter_packs (TYPE_RAISES_EXCEPTIONS (type))) 4616 TYPE_RAISES_EXCEPTIONS (type) = NULL_TREE; 4617 } 4618 else if (check_for_bare_parameter_packs ((TREE_CODE (decl) == TYPE_DECL 4619 && TYPE_DECL_ALIAS_P (decl)) 4620 ? DECL_ORIGINAL_TYPE (decl) 4621 : TREE_TYPE (decl))) 4622 { 4623 TREE_TYPE (decl) = error_mark_node; 4624 return error_mark_node; 4625 } 4626 4627 if (is_partial) 4628 return process_partial_specialization (decl); 4629 4630 args = current_template_args (); 4631 4632 if (!ctx 4633 || TREE_CODE (ctx) == FUNCTION_DECL 4634 || (CLASS_TYPE_P (ctx) && TYPE_BEING_DEFINED (ctx)) 4635 || (is_friend && !DECL_TEMPLATE_INFO (decl))) 4636 { 4637 if (DECL_LANG_SPECIFIC (decl) 4638 && DECL_TEMPLATE_INFO (decl) 4639 && DECL_TI_TEMPLATE (decl)) 4640 tmpl = DECL_TI_TEMPLATE (decl); 4641 /* If DECL is a TYPE_DECL for a class-template, then there won't 4642 be DECL_LANG_SPECIFIC. The information equivalent to 4643 DECL_TEMPLATE_INFO is found in TYPE_TEMPLATE_INFO instead. */ 4644 else if (DECL_IMPLICIT_TYPEDEF_P (decl) 4645 && TYPE_TEMPLATE_INFO (TREE_TYPE (decl)) 4646 && TYPE_TI_TEMPLATE (TREE_TYPE (decl))) 4647 { 4648 /* Since a template declaration already existed for this 4649 class-type, we must be redeclaring it here. Make sure 4650 that the redeclaration is valid. */ 4651 redeclare_class_template (TREE_TYPE (decl), 4652 current_template_parms); 4653 /* We don't need to create a new TEMPLATE_DECL; just use the 4654 one we already had. */ 4655 tmpl = TYPE_TI_TEMPLATE (TREE_TYPE (decl)); 4656 } 4657 else 4658 { 4659 tmpl = build_template_decl (decl, current_template_parms, 4660 member_template_p); 4661 new_template_p = 1; 4662 4663 if (DECL_LANG_SPECIFIC (decl) 4664 && DECL_TEMPLATE_SPECIALIZATION (decl)) 4665 { 4666 /* A specialization of a member template of a template 4667 class. */ 4668 SET_DECL_TEMPLATE_SPECIALIZATION (tmpl); 4669 DECL_TEMPLATE_INFO (tmpl) = DECL_TEMPLATE_INFO (decl); 4670 DECL_TEMPLATE_INFO (decl) = NULL_TREE; 4671 } 4672 } 4673 } 4674 else 4675 { 4676 tree a, t, current, parms; 4677 int i; 4678 tree tinfo = get_template_info (decl); 4679 4680 if (!tinfo) 4681 { 4682 error ("template definition of non-template %q#D", decl); 4683 return error_mark_node; 4684 } 4685 4686 tmpl = TI_TEMPLATE (tinfo); 4687 4688 if (DECL_FUNCTION_TEMPLATE_P (tmpl) 4689 && DECL_TEMPLATE_INFO (decl) && DECL_TI_ARGS (decl) 4690 && DECL_TEMPLATE_SPECIALIZATION (decl) 4691 && DECL_MEMBER_TEMPLATE_P (tmpl)) 4692 { 4693 tree new_tmpl; 4694 4695 /* The declaration is a specialization of a member 4696 template, declared outside the class. Therefore, the 4697 innermost template arguments will be NULL, so we 4698 replace them with the arguments determined by the 4699 earlier call to check_explicit_specialization. */ 4700 args = DECL_TI_ARGS (decl); 4701 4702 new_tmpl 4703 = build_template_decl (decl, current_template_parms, 4704 member_template_p); 4705 DECL_TEMPLATE_RESULT (new_tmpl) = decl; 4706 TREE_TYPE (new_tmpl) = TREE_TYPE (decl); 4707 DECL_TI_TEMPLATE (decl) = new_tmpl; 4708 SET_DECL_TEMPLATE_SPECIALIZATION (new_tmpl); 4709 DECL_TEMPLATE_INFO (new_tmpl) 4710 = build_template_info (tmpl, args); 4711 4712 register_specialization (new_tmpl, 4713 most_general_template (tmpl), 4714 args, 4715 is_friend, 0); 4716 return decl; 4717 } 4718 4719 /* Make sure the template headers we got make sense. */ 4720 4721 parms = DECL_TEMPLATE_PARMS (tmpl); 4722 i = TMPL_PARMS_DEPTH (parms); 4723 if (TMPL_ARGS_DEPTH (args) != i) 4724 { 4725 error ("expected %d levels of template parms for %q#D, got %d", 4726 i, decl, TMPL_ARGS_DEPTH (args)); 4727 } 4728 else 4729 for (current = decl; i > 0; --i, parms = TREE_CHAIN (parms)) 4730 { 4731 a = TMPL_ARGS_LEVEL (args, i); 4732 t = INNERMOST_TEMPLATE_PARMS (parms); 4733 4734 if (TREE_VEC_LENGTH (t) != TREE_VEC_LENGTH (a)) 4735 { 4736 if (current == decl) 4737 error ("got %d template parameters for %q#D", 4738 TREE_VEC_LENGTH (a), decl); 4739 else 4740 error ("got %d template parameters for %q#T", 4741 TREE_VEC_LENGTH (a), current); 4742 error (" but %d required", TREE_VEC_LENGTH (t)); 4743 /* Avoid crash in import_export_decl. */ 4744 DECL_INTERFACE_KNOWN (decl) = 1; 4745 return error_mark_node; 4746 } 4747 4748 if (current == decl) 4749 current = ctx; 4750 else if (current == NULL_TREE) 4751 /* Can happen in erroneous input. */ 4752 break; 4753 else 4754 current = (TYPE_P (current) 4755 ? TYPE_CONTEXT (current) 4756 : DECL_CONTEXT (current)); 4757 } 4758 4759 /* Check that the parms are used in the appropriate qualifying scopes 4760 in the declarator. */ 4761 if (!comp_template_args 4762 (TI_ARGS (tinfo), 4763 TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (tmpl))))) 4764 { 4765 error ("\ 4766 template arguments to %qD do not match original template %qD", 4767 decl, DECL_TEMPLATE_RESULT (tmpl)); 4768 if (!uses_template_parms (TI_ARGS (tinfo))) 4769 inform (input_location, "use template<> for an explicit specialization"); 4770 /* Avoid crash in import_export_decl. */ 4771 DECL_INTERFACE_KNOWN (decl) = 1; 4772 return error_mark_node; 4773 } 4774 } 4775 4776 DECL_TEMPLATE_RESULT (tmpl) = decl; 4777 TREE_TYPE (tmpl) = TREE_TYPE (decl); 4778 4779 /* Push template declarations for global functions and types. Note 4780 that we do not try to push a global template friend declared in a 4781 template class; such a thing may well depend on the template 4782 parameters of the class. */ 4783 if (new_template_p && !ctx 4784 && !(is_friend && template_class_depth (current_class_type) > 0)) 4785 { 4786 tmpl = pushdecl_namespace_level (tmpl, is_friend); 4787 if (tmpl == error_mark_node) 4788 return error_mark_node; 4789 4790 /* Hide template friend classes that haven't been declared yet. */ 4791 if (is_friend && TREE_CODE (decl) == TYPE_DECL) 4792 { 4793 DECL_ANTICIPATED (tmpl) = 1; 4794 DECL_FRIEND_P (tmpl) = 1; 4795 } 4796 } 4797 4798 if (primary) 4799 { 4800 tree parms = DECL_TEMPLATE_PARMS (tmpl); 4801 int i; 4802 4803 DECL_PRIMARY_TEMPLATE (tmpl) = tmpl; 4804 if (DECL_CONV_FN_P (tmpl)) 4805 { 4806 int depth = TMPL_PARMS_DEPTH (parms); 4807 4808 /* It is a conversion operator. See if the type converted to 4809 depends on innermost template operands. */ 4810 4811 if (uses_template_parms_level (TREE_TYPE (TREE_TYPE (tmpl)), 4812 depth)) 4813 DECL_TEMPLATE_CONV_FN_P (tmpl) = 1; 4814 } 4815 4816 /* Give template template parms a DECL_CONTEXT of the template 4817 for which they are a parameter. */ 4818 parms = INNERMOST_TEMPLATE_PARMS (parms); 4819 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i) 4820 { 4821 tree parm = TREE_VALUE (TREE_VEC_ELT (parms, i)); 4822 if (TREE_CODE (parm) == TEMPLATE_DECL) 4823 DECL_CONTEXT (parm) = tmpl; 4824 } 4825 } 4826 4827 /* The DECL_TI_ARGS of DECL contains full set of arguments referring 4828 back to its most general template. If TMPL is a specialization, 4829 ARGS may only have the innermost set of arguments. Add the missing 4830 argument levels if necessary. */ 4831 if (DECL_TEMPLATE_INFO (tmpl)) 4832 args = add_outermost_template_args (DECL_TI_ARGS (tmpl), args); 4833 4834 info = build_template_info (tmpl, args); 4835 4836 if (DECL_IMPLICIT_TYPEDEF_P (decl)) 4837 SET_TYPE_TEMPLATE_INFO (TREE_TYPE (tmpl), info); 4838 else 4839 { 4840 if (primary && !DECL_LANG_SPECIFIC (decl)) 4841 retrofit_lang_decl (decl); 4842 if (DECL_LANG_SPECIFIC (decl)) 4843 DECL_TEMPLATE_INFO (decl) = info; 4844 } 4845 4846 return DECL_TEMPLATE_RESULT (tmpl); 4847 } 4848 4849 tree 4850 push_template_decl (tree decl) 4851 { 4852 return push_template_decl_real (decl, false); 4853 } 4854 4855 /* Called when a class template TYPE is redeclared with the indicated 4856 template PARMS, e.g.: 4857 4858 template <class T> struct S; 4859 template <class T> struct S {}; */ 4860 4861 bool 4862 redeclare_class_template (tree type, tree parms) 4863 { 4864 tree tmpl; 4865 tree tmpl_parms; 4866 int i; 4867 4868 if (!TYPE_TEMPLATE_INFO (type)) 4869 { 4870 error ("%qT is not a template type", type); 4871 return false; 4872 } 4873 4874 tmpl = TYPE_TI_TEMPLATE (type); 4875 if (!PRIMARY_TEMPLATE_P (tmpl)) 4876 /* The type is nested in some template class. Nothing to worry 4877 about here; there are no new template parameters for the nested 4878 type. */ 4879 return true; 4880 4881 if (!parms) 4882 { 4883 error ("template specifiers not specified in declaration of %qD", 4884 tmpl); 4885 return false; 4886 } 4887 4888 parms = INNERMOST_TEMPLATE_PARMS (parms); 4889 tmpl_parms = DECL_INNERMOST_TEMPLATE_PARMS (tmpl); 4890 4891 if (TREE_VEC_LENGTH (parms) != TREE_VEC_LENGTH (tmpl_parms)) 4892 { 4893 error_n (input_location, TREE_VEC_LENGTH (parms), 4894 "redeclared with %d template parameter", 4895 "redeclared with %d template parameters", 4896 TREE_VEC_LENGTH (parms)); 4897 inform_n (input_location, TREE_VEC_LENGTH (tmpl_parms), 4898 "previous declaration %q+D used %d template parameter", 4899 "previous declaration %q+D used %d template parameters", 4900 tmpl, TREE_VEC_LENGTH (tmpl_parms)); 4901 return false; 4902 } 4903 4904 for (i = 0; i < TREE_VEC_LENGTH (tmpl_parms); ++i) 4905 { 4906 tree tmpl_parm; 4907 tree parm; 4908 tree tmpl_default; 4909 tree parm_default; 4910 4911 if (TREE_VEC_ELT (tmpl_parms, i) == error_mark_node 4912 || TREE_VEC_ELT (parms, i) == error_mark_node) 4913 continue; 4914 4915 tmpl_parm = TREE_VALUE (TREE_VEC_ELT (tmpl_parms, i)); 4916 if (tmpl_parm == error_mark_node) 4917 return false; 4918 4919 parm = TREE_VALUE (TREE_VEC_ELT (parms, i)); 4920 tmpl_default = TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)); 4921 parm_default = TREE_PURPOSE (TREE_VEC_ELT (parms, i)); 4922 4923 /* TMPL_PARM and PARM can be either TYPE_DECL, PARM_DECL, or 4924 TEMPLATE_DECL. */ 4925 if (TREE_CODE (tmpl_parm) != TREE_CODE (parm) 4926 || (TREE_CODE (tmpl_parm) != TYPE_DECL 4927 && !same_type_p (TREE_TYPE (tmpl_parm), TREE_TYPE (parm))) 4928 || (TREE_CODE (tmpl_parm) != PARM_DECL 4929 && (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (tmpl_parm)) 4930 != TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm)))) 4931 || (TREE_CODE (tmpl_parm) == PARM_DECL 4932 && (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (tmpl_parm)) 4933 != TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))))) 4934 { 4935 error ("template parameter %q+#D", tmpl_parm); 4936 error ("redeclared here as %q#D", parm); 4937 return false; 4938 } 4939 4940 if (tmpl_default != NULL_TREE && parm_default != NULL_TREE) 4941 { 4942 /* We have in [temp.param]: 4943 4944 A template-parameter may not be given default arguments 4945 by two different declarations in the same scope. */ 4946 error_at (input_location, "redefinition of default argument for %q#D", parm); 4947 inform (DECL_SOURCE_LOCATION (tmpl_parm), 4948 "original definition appeared here"); 4949 return false; 4950 } 4951 4952 if (parm_default != NULL_TREE) 4953 /* Update the previous template parameters (which are the ones 4954 that will really count) with the new default value. */ 4955 TREE_PURPOSE (TREE_VEC_ELT (tmpl_parms, i)) = parm_default; 4956 else if (tmpl_default != NULL_TREE) 4957 /* Update the new parameters, too; they'll be used as the 4958 parameters for any members. */ 4959 TREE_PURPOSE (TREE_VEC_ELT (parms, i)) = tmpl_default; 4960 } 4961 4962 return true; 4963 } 4964 4965 /* Simplify EXPR if it is a non-dependent expression. Returns the 4966 (possibly simplified) expression. */ 4967 4968 static tree 4969 fold_non_dependent_expr_sfinae (tree expr, tsubst_flags_t complain) 4970 { 4971 if (expr == NULL_TREE) 4972 return NULL_TREE; 4973 4974 /* If we're in a template, but EXPR isn't value dependent, simplify 4975 it. We're supposed to treat: 4976 4977 template <typename T> void f(T[1 + 1]); 4978 template <typename T> void f(T[2]); 4979 4980 as two declarations of the same function, for example. */ 4981 if (processing_template_decl 4982 && !type_dependent_expression_p (expr) 4983 && potential_constant_expression (expr) 4984 && !value_dependent_expression_p (expr)) 4985 { 4986 HOST_WIDE_INT saved_processing_template_decl; 4987 4988 saved_processing_template_decl = processing_template_decl; 4989 processing_template_decl = 0; 4990 expr = tsubst_copy_and_build (expr, 4991 /*args=*/NULL_TREE, 4992 complain, 4993 /*in_decl=*/NULL_TREE, 4994 /*function_p=*/false, 4995 /*integral_constant_expression_p=*/true); 4996 processing_template_decl = saved_processing_template_decl; 4997 } 4998 return expr; 4999 } 5000 5001 tree 5002 fold_non_dependent_expr (tree expr) 5003 { 5004 return fold_non_dependent_expr_sfinae (expr, tf_error); 5005 } 5006 5007 /* Return TRUE iff T is a type alias, a TEMPLATE_DECL for an alias 5008 template declaration, or a TYPE_DECL for an alias declaration. */ 5009 5010 bool 5011 alias_type_or_template_p (tree t) 5012 { 5013 if (t == NULL_TREE) 5014 return false; 5015 return ((TREE_CODE (t) == TYPE_DECL && TYPE_DECL_ALIAS_P (t)) 5016 || (TYPE_P (t) 5017 && TYPE_NAME (t) 5018 && TYPE_DECL_ALIAS_P (TYPE_NAME (t))) 5019 || DECL_ALIAS_TEMPLATE_P (t)); 5020 } 5021 5022 /* Return TRUE iff is a specialization of an alias template. */ 5023 5024 bool 5025 alias_template_specialization_p (tree t) 5026 { 5027 if (t == NULL_TREE) 5028 return false; 5029 return (primary_template_instantiation_p (t) 5030 && DECL_ALIAS_TEMPLATE_P (TYPE_TI_TEMPLATE (t))); 5031 } 5032 5033 /* Subroutine of convert_nontype_argument. Converts EXPR to TYPE, which 5034 must be a function or a pointer-to-function type, as specified 5035 in [temp.arg.nontype]: disambiguate EXPR if it is an overload set, 5036 and check that the resulting function has external linkage. */ 5037 5038 static tree 5039 convert_nontype_argument_function (tree type, tree expr) 5040 { 5041 tree fns = expr; 5042 tree fn, fn_no_ptr; 5043 linkage_kind linkage; 5044 5045 fn = instantiate_type (type, fns, tf_none); 5046 if (fn == error_mark_node) 5047 return error_mark_node; 5048 5049 fn_no_ptr = fn; 5050 if (TREE_CODE (fn_no_ptr) == ADDR_EXPR) 5051 fn_no_ptr = TREE_OPERAND (fn_no_ptr, 0); 5052 if (BASELINK_P (fn_no_ptr)) 5053 fn_no_ptr = BASELINK_FUNCTIONS (fn_no_ptr); 5054 5055 /* [temp.arg.nontype]/1 5056 5057 A template-argument for a non-type, non-template template-parameter 5058 shall be one of: 5059 [...] 5060 -- the address of an object or function with external [C++11: or 5061 internal] linkage. */ 5062 linkage = decl_linkage (fn_no_ptr); 5063 if (cxx_dialect >= cxx0x ? linkage == lk_none : linkage != lk_external) 5064 { 5065 if (cxx_dialect >= cxx0x) 5066 error ("%qE is not a valid template argument for type %qT " 5067 "because %qD has no linkage", 5068 expr, type, fn_no_ptr); 5069 else 5070 error ("%qE is not a valid template argument for type %qT " 5071 "because %qD does not have external linkage", 5072 expr, type, fn_no_ptr); 5073 return NULL_TREE; 5074 } 5075 5076 return fn; 5077 } 5078 5079 /* Subroutine of convert_nontype_argument. 5080 Check if EXPR of type TYPE is a valid pointer-to-member constant. 5081 Emit an error otherwise. */ 5082 5083 static bool 5084 check_valid_ptrmem_cst_expr (tree type, tree expr, 5085 tsubst_flags_t complain) 5086 { 5087 STRIP_NOPS (expr); 5088 if (expr && (null_ptr_cst_p (expr) || TREE_CODE (expr) == PTRMEM_CST)) 5089 return true; 5090 if (cxx_dialect >= cxx0x && null_member_pointer_value_p (expr)) 5091 return true; 5092 if (complain & tf_error) 5093 { 5094 error ("%qE is not a valid template argument for type %qT", 5095 expr, type); 5096 error ("it must be a pointer-to-member of the form %<&X::Y%>"); 5097 } 5098 return false; 5099 } 5100 5101 /* Returns TRUE iff the address of OP is value-dependent. 5102 5103 14.6.2.4 [temp.dep.temp]: 5104 A non-integral non-type template-argument is dependent if its type is 5105 dependent or it has either of the following forms 5106 qualified-id 5107 & qualified-id 5108 and contains a nested-name-specifier which specifies a class-name that 5109 names a dependent type. 5110 5111 We generalize this to just say that the address of a member of a 5112 dependent class is value-dependent; the above doesn't cover the 5113 address of a static data member named with an unqualified-id. */ 5114 5115 static bool 5116 has_value_dependent_address (tree op) 5117 { 5118 /* We could use get_inner_reference here, but there's no need; 5119 this is only relevant for template non-type arguments, which 5120 can only be expressed as &id-expression. */ 5121 if (DECL_P (op)) 5122 { 5123 tree ctx = CP_DECL_CONTEXT (op); 5124 if (TYPE_P (ctx) && dependent_type_p (ctx)) 5125 return true; 5126 } 5127 5128 return false; 5129 } 5130 5131 /* The next set of functions are used for providing helpful explanatory 5132 diagnostics for failed overload resolution. Their messages should be 5133 indented by two spaces for consistency with the messages in 5134 call.c */ 5135 5136 static int 5137 unify_success (bool explain_p ATTRIBUTE_UNUSED) 5138 { 5139 return 0; 5140 } 5141 5142 static int 5143 unify_parameter_deduction_failure (bool explain_p, tree parm) 5144 { 5145 if (explain_p) 5146 inform (input_location, 5147 " couldn't deduce template parameter %qD", parm); 5148 return 1; 5149 } 5150 5151 static int 5152 unify_invalid (bool explain_p ATTRIBUTE_UNUSED) 5153 { 5154 return 1; 5155 } 5156 5157 static int 5158 unify_cv_qual_mismatch (bool explain_p, tree parm, tree arg) 5159 { 5160 if (explain_p) 5161 inform (input_location, 5162 " types %qT and %qT have incompatible cv-qualifiers", 5163 parm, arg); 5164 return 1; 5165 } 5166 5167 static int 5168 unify_type_mismatch (bool explain_p, tree parm, tree arg) 5169 { 5170 if (explain_p) 5171 inform (input_location, " mismatched types %qT and %qT", parm, arg); 5172 return 1; 5173 } 5174 5175 static int 5176 unify_parameter_pack_mismatch (bool explain_p, tree parm, tree arg) 5177 { 5178 if (explain_p) 5179 inform (input_location, 5180 " template parameter %qD is not a parameter pack, but " 5181 "argument %qD is", 5182 parm, arg); 5183 return 1; 5184 } 5185 5186 static int 5187 unify_ptrmem_cst_mismatch (bool explain_p, tree parm, tree arg) 5188 { 5189 if (explain_p) 5190 inform (input_location, 5191 " template argument %qE does not match " 5192 "pointer-to-member constant %qE", 5193 arg, parm); 5194 return 1; 5195 } 5196 5197 static int 5198 unify_expression_unequal (bool explain_p, tree parm, tree arg) 5199 { 5200 if (explain_p) 5201 inform (input_location, " %qE is not equivalent to %qE", parm, arg); 5202 return 1; 5203 } 5204 5205 static int 5206 unify_parameter_pack_inconsistent (bool explain_p, tree old_arg, tree new_arg) 5207 { 5208 if (explain_p) 5209 inform (input_location, 5210 " inconsistent parameter pack deduction with %qT and %qT", 5211 old_arg, new_arg); 5212 return 1; 5213 } 5214 5215 static int 5216 unify_inconsistency (bool explain_p, tree parm, tree first, tree second) 5217 { 5218 if (explain_p) 5219 { 5220 if (TYPE_P (parm)) 5221 inform (input_location, 5222 " deduced conflicting types for parameter %qT (%qT and %qT)", 5223 parm, first, second); 5224 else 5225 inform (input_location, 5226 " deduced conflicting values for non-type parameter " 5227 "%qE (%qE and %qE)", parm, first, second); 5228 } 5229 return 1; 5230 } 5231 5232 static int 5233 unify_vla_arg (bool explain_p, tree arg) 5234 { 5235 if (explain_p) 5236 inform (input_location, 5237 " variable-sized array type %qT is not " 5238 "a valid template argument", 5239 arg); 5240 return 1; 5241 } 5242 5243 static int 5244 unify_method_type_error (bool explain_p, tree arg) 5245 { 5246 if (explain_p) 5247 inform (input_location, 5248 " member function type %qT is not a valid template argument", 5249 arg); 5250 return 1; 5251 } 5252 5253 static int 5254 unify_arity (bool explain_p, int have, int wanted) 5255 { 5256 if (explain_p) 5257 inform_n (input_location, wanted, 5258 " candidate expects %d argument, %d provided", 5259 " candidate expects %d arguments, %d provided", 5260 wanted, have); 5261 return 1; 5262 } 5263 5264 static int 5265 unify_too_many_arguments (bool explain_p, int have, int wanted) 5266 { 5267 return unify_arity (explain_p, have, wanted); 5268 } 5269 5270 static int 5271 unify_too_few_arguments (bool explain_p, int have, int wanted) 5272 { 5273 return unify_arity (explain_p, have, wanted); 5274 } 5275 5276 static int 5277 unify_arg_conversion (bool explain_p, tree to_type, 5278 tree from_type, tree arg) 5279 { 5280 if (explain_p) 5281 inform (input_location, " cannot convert %qE (type %qT) to type %qT", 5282 arg, from_type, to_type); 5283 return 1; 5284 } 5285 5286 static int 5287 unify_no_common_base (bool explain_p, enum template_base_result r, 5288 tree parm, tree arg) 5289 { 5290 if (explain_p) 5291 switch (r) 5292 { 5293 case tbr_ambiguous_baseclass: 5294 inform (input_location, " %qT is an ambiguous base class of %qT", 5295 arg, parm); 5296 break; 5297 default: 5298 inform (input_location, " %qT is not derived from %qT", arg, parm); 5299 break; 5300 } 5301 return 1; 5302 } 5303 5304 static int 5305 unify_inconsistent_template_template_parameters (bool explain_p) 5306 { 5307 if (explain_p) 5308 inform (input_location, 5309 " template parameters of a template template argument are " 5310 "inconsistent with other deduced template arguments"); 5311 return 1; 5312 } 5313 5314 static int 5315 unify_template_deduction_failure (bool explain_p, tree parm, tree arg) 5316 { 5317 if (explain_p) 5318 inform (input_location, 5319 " can't deduce a template for %qT from non-template type %qT", 5320 parm, arg); 5321 return 1; 5322 } 5323 5324 static int 5325 unify_template_argument_mismatch (bool explain_p, tree parm, tree arg) 5326 { 5327 if (explain_p) 5328 inform (input_location, 5329 " template argument %qE does not match %qD", arg, parm); 5330 return 1; 5331 } 5332 5333 static int 5334 unify_overload_resolution_failure (bool explain_p, tree arg) 5335 { 5336 if (explain_p) 5337 inform (input_location, 5338 " could not resolve address from overloaded function %qE", 5339 arg); 5340 return 1; 5341 } 5342 5343 /* Attempt to convert the non-type template parameter EXPR to the 5344 indicated TYPE. If the conversion is successful, return the 5345 converted value. If the conversion is unsuccessful, return 5346 NULL_TREE if we issued an error message, or error_mark_node if we 5347 did not. We issue error messages for out-and-out bad template 5348 parameters, but not simply because the conversion failed, since we 5349 might be just trying to do argument deduction. Both TYPE and EXPR 5350 must be non-dependent. 5351 5352 The conversion follows the special rules described in 5353 [temp.arg.nontype], and it is much more strict than an implicit 5354 conversion. 5355 5356 This function is called twice for each template argument (see 5357 lookup_template_class for a more accurate description of this 5358 problem). This means that we need to handle expressions which 5359 are not valid in a C++ source, but can be created from the 5360 first call (for instance, casts to perform conversions). These 5361 hacks can go away after we fix the double coercion problem. */ 5362 5363 static tree 5364 convert_nontype_argument (tree type, tree expr, tsubst_flags_t complain) 5365 { 5366 tree expr_type; 5367 5368 /* Detect immediately string literals as invalid non-type argument. 5369 This special-case is not needed for correctness (we would easily 5370 catch this later), but only to provide better diagnostic for this 5371 common user mistake. As suggested by DR 100, we do not mention 5372 linkage issues in the diagnostic as this is not the point. */ 5373 /* FIXME we're making this OK. */ 5374 if (TREE_CODE (expr) == STRING_CST) 5375 { 5376 if (complain & tf_error) 5377 error ("%qE is not a valid template argument for type %qT " 5378 "because string literals can never be used in this context", 5379 expr, type); 5380 return NULL_TREE; 5381 } 5382 5383 /* Add the ADDR_EXPR now for the benefit of 5384 value_dependent_expression_p. */ 5385 if (TYPE_PTROBV_P (type) 5386 && TREE_CODE (TREE_TYPE (expr)) == ARRAY_TYPE) 5387 expr = decay_conversion (expr); 5388 5389 /* If we are in a template, EXPR may be non-dependent, but still 5390 have a syntactic, rather than semantic, form. For example, EXPR 5391 might be a SCOPE_REF, rather than the VAR_DECL to which the 5392 SCOPE_REF refers. Preserving the qualifying scope is necessary 5393 so that access checking can be performed when the template is 5394 instantiated -- but here we need the resolved form so that we can 5395 convert the argument. */ 5396 if (TYPE_REF_OBJ_P (type) 5397 && has_value_dependent_address (expr)) 5398 /* If we want the address and it's value-dependent, don't fold. */; 5399 else if (!type_unknown_p (expr)) 5400 expr = fold_non_dependent_expr_sfinae (expr, complain); 5401 if (error_operand_p (expr)) 5402 return error_mark_node; 5403 expr_type = TREE_TYPE (expr); 5404 if (TREE_CODE (type) == REFERENCE_TYPE) 5405 expr = mark_lvalue_use (expr); 5406 else 5407 expr = mark_rvalue_use (expr); 5408 5409 /* 14.3.2/5: The null pointer{,-to-member} conversion is applied 5410 to a non-type argument of "nullptr". */ 5411 if (expr == nullptr_node 5412 && (TYPE_PTR_P (type) || TYPE_PTR_TO_MEMBER_P (type))) 5413 expr = convert (type, expr); 5414 5415 /* In C++11, integral or enumeration non-type template arguments can be 5416 arbitrary constant expressions. Pointer and pointer to 5417 member arguments can be general constant expressions that evaluate 5418 to a null value, but otherwise still need to be of a specific form. */ 5419 if (cxx_dialect >= cxx0x) 5420 { 5421 if (TREE_CODE (expr) == PTRMEM_CST) 5422 /* A PTRMEM_CST is already constant, and a valid template 5423 argument for a parameter of pointer to member type, we just want 5424 to leave it in that form rather than lower it to a 5425 CONSTRUCTOR. */; 5426 else if (INTEGRAL_OR_ENUMERATION_TYPE_P (type)) 5427 expr = maybe_constant_value (expr); 5428 else if (TYPE_PTR_P (type) 5429 || TYPE_PTR_TO_MEMBER_P (type)) 5430 { 5431 tree folded = maybe_constant_value (expr); 5432 if (TYPE_PTR_P (type) ? integer_zerop (folded) 5433 : null_member_pointer_value_p (folded)) 5434 expr = folded; 5435 } 5436 } 5437 5438 /* HACK: Due to double coercion, we can get a 5439 NOP_EXPR<REFERENCE_TYPE>(ADDR_EXPR<POINTER_TYPE> (arg)) here, 5440 which is the tree that we built on the first call (see 5441 below when coercing to reference to object or to reference to 5442 function). We just strip everything and get to the arg. 5443 See g++.old-deja/g++.oliva/template4.C and g++.dg/template/nontype9.C 5444 for examples. */ 5445 if (TYPE_REF_OBJ_P (type) || TYPE_REFFN_P (type)) 5446 { 5447 tree probe_type, probe = expr; 5448 if (REFERENCE_REF_P (probe)) 5449 probe = TREE_OPERAND (probe, 0); 5450 probe_type = TREE_TYPE (probe); 5451 if (TREE_CODE (probe) == NOP_EXPR) 5452 { 5453 /* ??? Maybe we could use convert_from_reference here, but we 5454 would need to relax its constraints because the NOP_EXPR 5455 could actually change the type to something more cv-qualified, 5456 and this is not folded by convert_from_reference. */ 5457 tree addr = TREE_OPERAND (probe, 0); 5458 gcc_assert (TREE_CODE (probe_type) == REFERENCE_TYPE); 5459 gcc_assert (TREE_CODE (addr) == ADDR_EXPR); 5460 gcc_assert (TREE_CODE (TREE_TYPE (addr)) == POINTER_TYPE); 5461 gcc_assert (same_type_ignoring_top_level_qualifiers_p 5462 (TREE_TYPE (probe_type), 5463 TREE_TYPE (TREE_TYPE (addr)))); 5464 5465 expr = TREE_OPERAND (addr, 0); 5466 expr_type = TREE_TYPE (expr); 5467 } 5468 } 5469 5470 /* We could also generate a NOP_EXPR(ADDR_EXPR()) when the 5471 parameter is a pointer to object, through decay and 5472 qualification conversion. Let's strip everything. */ 5473 else if (TREE_CODE (expr) == NOP_EXPR && TYPE_PTROBV_P (type)) 5474 { 5475 STRIP_NOPS (expr); 5476 gcc_assert (TREE_CODE (expr) == ADDR_EXPR); 5477 gcc_assert (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE); 5478 /* Skip the ADDR_EXPR only if it is part of the decay for 5479 an array. Otherwise, it is part of the original argument 5480 in the source code. */ 5481 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (expr, 0))) == ARRAY_TYPE) 5482 expr = TREE_OPERAND (expr, 0); 5483 expr_type = TREE_TYPE (expr); 5484 } 5485 5486 /* [temp.arg.nontype]/5, bullet 1 5487 5488 For a non-type template-parameter of integral or enumeration type, 5489 integral promotions (_conv.prom_) and integral conversions 5490 (_conv.integral_) are applied. */ 5491 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type)) 5492 { 5493 tree t = build_integral_nontype_arg_conv (type, expr, complain); 5494 t = maybe_constant_value (t); 5495 if (t != error_mark_node) 5496 expr = t; 5497 5498 if (!same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (expr))) 5499 return error_mark_node; 5500 5501 /* Notice that there are constant expressions like '4 % 0' which 5502 do not fold into integer constants. */ 5503 if (TREE_CODE (expr) != INTEGER_CST) 5504 { 5505 if (complain & tf_error) 5506 { 5507 int errs = errorcount, warns = warningcount; 5508 if (processing_template_decl 5509 && !require_potential_constant_expression (expr)) 5510 return NULL_TREE; 5511 expr = cxx_constant_value (expr); 5512 if (errorcount > errs || warningcount > warns) 5513 inform (EXPR_LOC_OR_HERE (expr), 5514 "in template argument for type %qT ", type); 5515 if (expr == error_mark_node) 5516 return NULL_TREE; 5517 /* else cxx_constant_value complained but gave us 5518 a real constant, so go ahead. */ 5519 gcc_assert (TREE_CODE (expr) == INTEGER_CST); 5520 } 5521 else 5522 return NULL_TREE; 5523 } 5524 } 5525 /* [temp.arg.nontype]/5, bullet 2 5526 5527 For a non-type template-parameter of type pointer to object, 5528 qualification conversions (_conv.qual_) and the array-to-pointer 5529 conversion (_conv.array_) are applied. */ 5530 else if (TYPE_PTROBV_P (type)) 5531 { 5532 /* [temp.arg.nontype]/1 (TC1 version, DR 49): 5533 5534 A template-argument for a non-type, non-template template-parameter 5535 shall be one of: [...] 5536 5537 -- the name of a non-type template-parameter; 5538 -- the address of an object or function with external linkage, [...] 5539 expressed as "& id-expression" where the & is optional if the name 5540 refers to a function or array, or if the corresponding 5541 template-parameter is a reference. 5542 5543 Here, we do not care about functions, as they are invalid anyway 5544 for a parameter of type pointer-to-object. */ 5545 5546 if (DECL_P (expr) && DECL_TEMPLATE_PARM_P (expr)) 5547 /* Non-type template parameters are OK. */ 5548 ; 5549 else if (cxx_dialect >= cxx0x && integer_zerop (expr)) 5550 /* Null pointer values are OK in C++11. */; 5551 else if (TREE_CODE (expr) != ADDR_EXPR 5552 && TREE_CODE (expr_type) != ARRAY_TYPE) 5553 { 5554 if (TREE_CODE (expr) == VAR_DECL) 5555 { 5556 error ("%qD is not a valid template argument " 5557 "because %qD is a variable, not the address of " 5558 "a variable", 5559 expr, expr); 5560 return NULL_TREE; 5561 } 5562 /* Other values, like integer constants, might be valid 5563 non-type arguments of some other type. */ 5564 return error_mark_node; 5565 } 5566 else 5567 { 5568 tree decl; 5569 5570 decl = ((TREE_CODE (expr) == ADDR_EXPR) 5571 ? TREE_OPERAND (expr, 0) : expr); 5572 if (TREE_CODE (decl) != VAR_DECL) 5573 { 5574 error ("%qE is not a valid template argument of type %qT " 5575 "because %qE is not a variable", 5576 expr, type, decl); 5577 return NULL_TREE; 5578 } 5579 else if (cxx_dialect < cxx0x && !DECL_EXTERNAL_LINKAGE_P (decl)) 5580 { 5581 error ("%qE is not a valid template argument of type %qT " 5582 "because %qD does not have external linkage", 5583 expr, type, decl); 5584 return NULL_TREE; 5585 } 5586 else if (cxx_dialect >= cxx0x && decl_linkage (decl) == lk_none) 5587 { 5588 error ("%qE is not a valid template argument of type %qT " 5589 "because %qD has no linkage", 5590 expr, type, decl); 5591 return NULL_TREE; 5592 } 5593 } 5594 5595 expr = decay_conversion (expr); 5596 if (expr == error_mark_node) 5597 return error_mark_node; 5598 5599 expr = perform_qualification_conversions (type, expr); 5600 if (expr == error_mark_node) 5601 return error_mark_node; 5602 } 5603 /* [temp.arg.nontype]/5, bullet 3 5604 5605 For a non-type template-parameter of type reference to object, no 5606 conversions apply. The type referred to by the reference may be more 5607 cv-qualified than the (otherwise identical) type of the 5608 template-argument. The template-parameter is bound directly to the 5609 template-argument, which must be an lvalue. */ 5610 else if (TYPE_REF_OBJ_P (type)) 5611 { 5612 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type), 5613 expr_type)) 5614 return error_mark_node; 5615 5616 if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type)) 5617 { 5618 error ("%qE is not a valid template argument for type %qT " 5619 "because of conflicts in cv-qualification", expr, type); 5620 return NULL_TREE; 5621 } 5622 5623 if (!real_lvalue_p (expr)) 5624 { 5625 error ("%qE is not a valid template argument for type %qT " 5626 "because it is not an lvalue", expr, type); 5627 return NULL_TREE; 5628 } 5629 5630 /* [temp.arg.nontype]/1 5631 5632 A template-argument for a non-type, non-template template-parameter 5633 shall be one of: [...] 5634 5635 -- the address of an object or function with external linkage. */ 5636 if (TREE_CODE (expr) == INDIRECT_REF 5637 && TYPE_REF_OBJ_P (TREE_TYPE (TREE_OPERAND (expr, 0)))) 5638 { 5639 expr = TREE_OPERAND (expr, 0); 5640 if (DECL_P (expr)) 5641 { 5642 error ("%q#D is not a valid template argument for type %qT " 5643 "because a reference variable does not have a constant " 5644 "address", expr, type); 5645 return NULL_TREE; 5646 } 5647 } 5648 5649 if (!DECL_P (expr)) 5650 { 5651 error ("%qE is not a valid template argument for type %qT " 5652 "because it is not an object with external linkage", 5653 expr, type); 5654 return NULL_TREE; 5655 } 5656 5657 if (!DECL_EXTERNAL_LINKAGE_P (expr)) 5658 { 5659 error ("%qE is not a valid template argument for type %qT " 5660 "because object %qD has not external linkage", 5661 expr, type, expr); 5662 return NULL_TREE; 5663 } 5664 5665 expr = build_nop (type, build_address (expr)); 5666 } 5667 /* [temp.arg.nontype]/5, bullet 4 5668 5669 For a non-type template-parameter of type pointer to function, only 5670 the function-to-pointer conversion (_conv.func_) is applied. If the 5671 template-argument represents a set of overloaded functions (or a 5672 pointer to such), the matching function is selected from the set 5673 (_over.over_). */ 5674 else if (TYPE_PTRFN_P (type)) 5675 { 5676 /* If the argument is a template-id, we might not have enough 5677 context information to decay the pointer. */ 5678 if (!type_unknown_p (expr_type)) 5679 { 5680 expr = decay_conversion (expr); 5681 if (expr == error_mark_node) 5682 return error_mark_node; 5683 } 5684 5685 if (cxx_dialect >= cxx0x && integer_zerop (expr)) 5686 /* Null pointer values are OK in C++11. */ 5687 return perform_qualification_conversions (type, expr); 5688 5689 expr = convert_nontype_argument_function (type, expr); 5690 if (!expr || expr == error_mark_node) 5691 return expr; 5692 5693 if (TREE_CODE (expr) != ADDR_EXPR) 5694 { 5695 error ("%qE is not a valid template argument for type %qT", expr, type); 5696 error ("it must be the address of a function with external linkage"); 5697 return NULL_TREE; 5698 } 5699 } 5700 /* [temp.arg.nontype]/5, bullet 5 5701 5702 For a non-type template-parameter of type reference to function, no 5703 conversions apply. If the template-argument represents a set of 5704 overloaded functions, the matching function is selected from the set 5705 (_over.over_). */ 5706 else if (TYPE_REFFN_P (type)) 5707 { 5708 if (TREE_CODE (expr) == ADDR_EXPR) 5709 { 5710 error ("%qE is not a valid template argument for type %qT " 5711 "because it is a pointer", expr, type); 5712 inform (input_location, "try using %qE instead", TREE_OPERAND (expr, 0)); 5713 return NULL_TREE; 5714 } 5715 5716 expr = convert_nontype_argument_function (TREE_TYPE (type), expr); 5717 if (!expr || expr == error_mark_node) 5718 return expr; 5719 5720 expr = build_nop (type, build_address (expr)); 5721 } 5722 /* [temp.arg.nontype]/5, bullet 6 5723 5724 For a non-type template-parameter of type pointer to member function, 5725 no conversions apply. If the template-argument represents a set of 5726 overloaded member functions, the matching member function is selected 5727 from the set (_over.over_). */ 5728 else if (TYPE_PTRMEMFUNC_P (type)) 5729 { 5730 expr = instantiate_type (type, expr, tf_none); 5731 if (expr == error_mark_node) 5732 return error_mark_node; 5733 5734 /* [temp.arg.nontype] bullet 1 says the pointer to member 5735 expression must be a pointer-to-member constant. */ 5736 if (!check_valid_ptrmem_cst_expr (type, expr, complain)) 5737 return error_mark_node; 5738 5739 /* There is no way to disable standard conversions in 5740 resolve_address_of_overloaded_function (called by 5741 instantiate_type). It is possible that the call succeeded by 5742 converting &B::I to &D::I (where B is a base of D), so we need 5743 to reject this conversion here. 5744 5745 Actually, even if there was a way to disable standard conversions, 5746 it would still be better to reject them here so that we can 5747 provide a superior diagnostic. */ 5748 if (!same_type_p (TREE_TYPE (expr), type)) 5749 { 5750 error ("%qE is not a valid template argument for type %qT " 5751 "because it is of type %qT", expr, type, 5752 TREE_TYPE (expr)); 5753 /* If we are just one standard conversion off, explain. */ 5754 if (can_convert (type, TREE_TYPE (expr))) 5755 inform (input_location, 5756 "standard conversions are not allowed in this context"); 5757 return NULL_TREE; 5758 } 5759 } 5760 /* [temp.arg.nontype]/5, bullet 7 5761 5762 For a non-type template-parameter of type pointer to data member, 5763 qualification conversions (_conv.qual_) are applied. */ 5764 else if (TYPE_PTRMEM_P (type)) 5765 { 5766 /* [temp.arg.nontype] bullet 1 says the pointer to member 5767 expression must be a pointer-to-member constant. */ 5768 if (!check_valid_ptrmem_cst_expr (type, expr, complain)) 5769 return error_mark_node; 5770 5771 expr = perform_qualification_conversions (type, expr); 5772 if (expr == error_mark_node) 5773 return expr; 5774 } 5775 else if (NULLPTR_TYPE_P (type)) 5776 { 5777 if (expr != nullptr_node) 5778 { 5779 error ("%qE is not a valid template argument for type %qT " 5780 "because it is of type %qT", expr, type, TREE_TYPE (expr)); 5781 return NULL_TREE; 5782 } 5783 return expr; 5784 } 5785 /* A template non-type parameter must be one of the above. */ 5786 else 5787 gcc_unreachable (); 5788 5789 /* Sanity check: did we actually convert the argument to the 5790 right type? */ 5791 gcc_assert (same_type_ignoring_top_level_qualifiers_p 5792 (type, TREE_TYPE (expr))); 5793 return expr; 5794 } 5795 5796 /* Subroutine of coerce_template_template_parms, which returns 1 if 5797 PARM_PARM and ARG_PARM match using the rule for the template 5798 parameters of template template parameters. Both PARM and ARG are 5799 template parameters; the rest of the arguments are the same as for 5800 coerce_template_template_parms. 5801 */ 5802 static int 5803 coerce_template_template_parm (tree parm, 5804 tree arg, 5805 tsubst_flags_t complain, 5806 tree in_decl, 5807 tree outer_args) 5808 { 5809 if (arg == NULL_TREE || arg == error_mark_node 5810 || parm == NULL_TREE || parm == error_mark_node) 5811 return 0; 5812 5813 if (TREE_CODE (arg) != TREE_CODE (parm)) 5814 return 0; 5815 5816 switch (TREE_CODE (parm)) 5817 { 5818 case TEMPLATE_DECL: 5819 /* We encounter instantiations of templates like 5820 template <template <template <class> class> class TT> 5821 class C; */ 5822 { 5823 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm); 5824 tree argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg); 5825 5826 if (!coerce_template_template_parms 5827 (parmparm, argparm, complain, in_decl, outer_args)) 5828 return 0; 5829 } 5830 /* Fall through. */ 5831 5832 case TYPE_DECL: 5833 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (arg)) 5834 && !TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))) 5835 /* Argument is a parameter pack but parameter is not. */ 5836 return 0; 5837 break; 5838 5839 case PARM_DECL: 5840 /* The tsubst call is used to handle cases such as 5841 5842 template <int> class C {}; 5843 template <class T, template <T> class TT> class D {}; 5844 D<int, C> d; 5845 5846 i.e. the parameter list of TT depends on earlier parameters. */ 5847 if (!uses_template_parms (TREE_TYPE (arg)) 5848 && !same_type_p 5849 (tsubst (TREE_TYPE (parm), outer_args, complain, in_decl), 5850 TREE_TYPE (arg))) 5851 return 0; 5852 5853 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (arg)) 5854 && !TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))) 5855 /* Argument is a parameter pack but parameter is not. */ 5856 return 0; 5857 5858 break; 5859 5860 default: 5861 gcc_unreachable (); 5862 } 5863 5864 return 1; 5865 } 5866 5867 5868 /* Return 1 if PARM_PARMS and ARG_PARMS matches using rule for 5869 template template parameters. Both PARM_PARMS and ARG_PARMS are 5870 vectors of TREE_LIST nodes containing TYPE_DECL, TEMPLATE_DECL 5871 or PARM_DECL. 5872 5873 Consider the example: 5874 template <class T> class A; 5875 template<template <class U> class TT> class B; 5876 5877 For B<A>, PARM_PARMS are the parameters to TT, while ARG_PARMS are 5878 the parameters to A, and OUTER_ARGS contains A. */ 5879 5880 static int 5881 coerce_template_template_parms (tree parm_parms, 5882 tree arg_parms, 5883 tsubst_flags_t complain, 5884 tree in_decl, 5885 tree outer_args) 5886 { 5887 int nparms, nargs, i; 5888 tree parm, arg; 5889 int variadic_p = 0; 5890 5891 gcc_assert (TREE_CODE (parm_parms) == TREE_VEC); 5892 gcc_assert (TREE_CODE (arg_parms) == TREE_VEC); 5893 5894 nparms = TREE_VEC_LENGTH (parm_parms); 5895 nargs = TREE_VEC_LENGTH (arg_parms); 5896 5897 /* Determine whether we have a parameter pack at the end of the 5898 template template parameter's template parameter list. */ 5899 if (TREE_VEC_ELT (parm_parms, nparms - 1) != error_mark_node) 5900 { 5901 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, nparms - 1)); 5902 5903 if (parm == error_mark_node) 5904 return 0; 5905 5906 switch (TREE_CODE (parm)) 5907 { 5908 case TEMPLATE_DECL: 5909 case TYPE_DECL: 5910 if (TEMPLATE_TYPE_PARAMETER_PACK (TREE_TYPE (parm))) 5911 variadic_p = 1; 5912 break; 5913 5914 case PARM_DECL: 5915 if (TEMPLATE_PARM_PARAMETER_PACK (DECL_INITIAL (parm))) 5916 variadic_p = 1; 5917 break; 5918 5919 default: 5920 gcc_unreachable (); 5921 } 5922 } 5923 5924 if (nargs != nparms 5925 && !(variadic_p && nargs >= nparms - 1)) 5926 return 0; 5927 5928 /* Check all of the template parameters except the parameter pack at 5929 the end (if any). */ 5930 for (i = 0; i < nparms - variadic_p; ++i) 5931 { 5932 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node 5933 || TREE_VEC_ELT (arg_parms, i) == error_mark_node) 5934 continue; 5935 5936 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i)); 5937 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i)); 5938 5939 if (!coerce_template_template_parm (parm, arg, complain, in_decl, 5940 outer_args)) 5941 return 0; 5942 5943 } 5944 5945 if (variadic_p) 5946 { 5947 /* Check each of the template parameters in the template 5948 argument against the template parameter pack at the end of 5949 the template template parameter. */ 5950 if (TREE_VEC_ELT (parm_parms, i) == error_mark_node) 5951 return 0; 5952 5953 parm = TREE_VALUE (TREE_VEC_ELT (parm_parms, i)); 5954 5955 for (; i < nargs; ++i) 5956 { 5957 if (TREE_VEC_ELT (arg_parms, i) == error_mark_node) 5958 continue; 5959 5960 arg = TREE_VALUE (TREE_VEC_ELT (arg_parms, i)); 5961 5962 if (!coerce_template_template_parm (parm, arg, complain, in_decl, 5963 outer_args)) 5964 return 0; 5965 } 5966 } 5967 5968 return 1; 5969 } 5970 5971 /* Verifies that the deduced template arguments (in TARGS) for the 5972 template template parameters (in TPARMS) represent valid bindings, 5973 by comparing the template parameter list of each template argument 5974 to the template parameter list of its corresponding template 5975 template parameter, in accordance with DR150. This 5976 routine can only be called after all template arguments have been 5977 deduced. It will return TRUE if all of the template template 5978 parameter bindings are okay, FALSE otherwise. */ 5979 bool 5980 template_template_parm_bindings_ok_p (tree tparms, tree targs) 5981 { 5982 int i, ntparms = TREE_VEC_LENGTH (tparms); 5983 bool ret = true; 5984 5985 /* We're dealing with template parms in this process. */ 5986 ++processing_template_decl; 5987 5988 targs = INNERMOST_TEMPLATE_ARGS (targs); 5989 5990 for (i = 0; i < ntparms; ++i) 5991 { 5992 tree tparm = TREE_VALUE (TREE_VEC_ELT (tparms, i)); 5993 tree targ = TREE_VEC_ELT (targs, i); 5994 5995 if (TREE_CODE (tparm) == TEMPLATE_DECL && targ) 5996 { 5997 tree packed_args = NULL_TREE; 5998 int idx, len = 1; 5999 6000 if (ARGUMENT_PACK_P (targ)) 6001 { 6002 /* Look inside the argument pack. */ 6003 packed_args = ARGUMENT_PACK_ARGS (targ); 6004 len = TREE_VEC_LENGTH (packed_args); 6005 } 6006 6007 for (idx = 0; idx < len; ++idx) 6008 { 6009 tree targ_parms = NULL_TREE; 6010 6011 if (packed_args) 6012 /* Extract the next argument from the argument 6013 pack. */ 6014 targ = TREE_VEC_ELT (packed_args, idx); 6015 6016 if (PACK_EXPANSION_P (targ)) 6017 /* Look at the pattern of the pack expansion. */ 6018 targ = PACK_EXPANSION_PATTERN (targ); 6019 6020 /* Extract the template parameters from the template 6021 argument. */ 6022 if (TREE_CODE (targ) == TEMPLATE_DECL) 6023 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (targ); 6024 else if (TREE_CODE (targ) == TEMPLATE_TEMPLATE_PARM) 6025 targ_parms = DECL_INNERMOST_TEMPLATE_PARMS (TYPE_NAME (targ)); 6026 6027 /* Verify that we can coerce the template template 6028 parameters from the template argument to the template 6029 parameter. This requires an exact match. */ 6030 if (targ_parms 6031 && !coerce_template_template_parms 6032 (DECL_INNERMOST_TEMPLATE_PARMS (tparm), 6033 targ_parms, 6034 tf_none, 6035 tparm, 6036 targs)) 6037 { 6038 ret = false; 6039 goto out; 6040 } 6041 } 6042 } 6043 } 6044 6045 out: 6046 6047 --processing_template_decl; 6048 return ret; 6049 } 6050 6051 /* Since type attributes aren't mangled, we need to strip them from 6052 template type arguments. */ 6053 6054 static tree 6055 canonicalize_type_argument (tree arg, tsubst_flags_t complain) 6056 { 6057 tree mv; 6058 if (!arg || arg == error_mark_node || arg == TYPE_CANONICAL (arg)) 6059 return arg; 6060 mv = TYPE_MAIN_VARIANT (arg); 6061 arg = strip_typedefs (arg); 6062 if (TYPE_ALIGN (arg) != TYPE_ALIGN (mv) 6063 || TYPE_ATTRIBUTES (arg) != TYPE_ATTRIBUTES (mv)) 6064 { 6065 if (complain & tf_warning) 6066 warning (0, "ignoring attributes on template argument %qT", arg); 6067 arg = build_aligned_type (arg, TYPE_ALIGN (mv)); 6068 arg = cp_build_type_attribute_variant (arg, TYPE_ATTRIBUTES (mv)); 6069 } 6070 return arg; 6071 } 6072 6073 /* Convert the indicated template ARG as necessary to match the 6074 indicated template PARM. Returns the converted ARG, or 6075 error_mark_node if the conversion was unsuccessful. Error and 6076 warning messages are issued under control of COMPLAIN. This 6077 conversion is for the Ith parameter in the parameter list. ARGS is 6078 the full set of template arguments deduced so far. */ 6079 6080 static tree 6081 convert_template_argument (tree parm, 6082 tree arg, 6083 tree args, 6084 tsubst_flags_t complain, 6085 int i, 6086 tree in_decl) 6087 { 6088 tree orig_arg; 6089 tree val; 6090 int is_type, requires_type, is_tmpl_type, requires_tmpl_type; 6091 6092 if (TREE_CODE (arg) == TREE_LIST 6093 && TREE_CODE (TREE_VALUE (arg)) == OFFSET_REF) 6094 { 6095 /* The template argument was the name of some 6096 member function. That's usually 6097 invalid, but static members are OK. In any 6098 case, grab the underlying fields/functions 6099 and issue an error later if required. */ 6100 orig_arg = TREE_VALUE (arg); 6101 TREE_TYPE (arg) = unknown_type_node; 6102 } 6103 6104 orig_arg = arg; 6105 6106 requires_tmpl_type = TREE_CODE (parm) == TEMPLATE_DECL; 6107 requires_type = (TREE_CODE (parm) == TYPE_DECL 6108 || requires_tmpl_type); 6109 6110 /* When determining whether an argument pack expansion is a template, 6111 look at the pattern. */ 6112 if (TREE_CODE (arg) == TYPE_PACK_EXPANSION) 6113 arg = PACK_EXPANSION_PATTERN (arg); 6114 6115 /* Deal with an injected-class-name used as a template template arg. */ 6116 if (requires_tmpl_type && CLASS_TYPE_P (arg)) 6117 { 6118 tree t = maybe_get_template_decl_from_type_decl (TYPE_NAME (arg)); 6119 if (TREE_CODE (t) == TEMPLATE_DECL) 6120 { 6121 if (cxx_dialect >= cxx0x) 6122 /* OK under DR 1004. */; 6123 else if (complain & tf_warning_or_error) 6124 pedwarn (input_location, OPT_pedantic, "injected-class-name %qD" 6125 " used as template template argument", TYPE_NAME (arg)); 6126 else if (flag_pedantic_errors) 6127 t = arg; 6128 6129 arg = t; 6130 } 6131 } 6132 6133 is_tmpl_type = 6134 ((TREE_CODE (arg) == TEMPLATE_DECL 6135 && TREE_CODE (DECL_TEMPLATE_RESULT (arg)) == TYPE_DECL) 6136 || (requires_tmpl_type && TREE_CODE (arg) == TYPE_ARGUMENT_PACK) 6137 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM 6138 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE); 6139 6140 if (is_tmpl_type 6141 && (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM 6142 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE)) 6143 arg = TYPE_STUB_DECL (arg); 6144 6145 is_type = TYPE_P (arg) || is_tmpl_type; 6146 6147 if (requires_type && ! is_type && TREE_CODE (arg) == SCOPE_REF 6148 && TREE_CODE (TREE_OPERAND (arg, 0)) == TEMPLATE_TYPE_PARM) 6149 { 6150 if (TREE_CODE (TREE_OPERAND (arg, 1)) == BIT_NOT_EXPR) 6151 { 6152 if (complain & tf_error) 6153 error ("invalid use of destructor %qE as a type", orig_arg); 6154 return error_mark_node; 6155 } 6156 6157 permerror (input_location, 6158 "to refer to a type member of a template parameter, " 6159 "use %<typename %E%>", orig_arg); 6160 6161 orig_arg = make_typename_type (TREE_OPERAND (arg, 0), 6162 TREE_OPERAND (arg, 1), 6163 typename_type, 6164 complain & tf_error); 6165 arg = orig_arg; 6166 is_type = 1; 6167 } 6168 if (is_type != requires_type) 6169 { 6170 if (in_decl) 6171 { 6172 if (complain & tf_error) 6173 { 6174 error ("type/value mismatch at argument %d in template " 6175 "parameter list for %qD", 6176 i + 1, in_decl); 6177 if (is_type) 6178 error (" expected a constant of type %qT, got %qT", 6179 TREE_TYPE (parm), 6180 (DECL_P (arg) ? DECL_NAME (arg) : orig_arg)); 6181 else if (requires_tmpl_type) 6182 error (" expected a class template, got %qE", orig_arg); 6183 else 6184 error (" expected a type, got %qE", orig_arg); 6185 } 6186 } 6187 return error_mark_node; 6188 } 6189 if (is_tmpl_type ^ requires_tmpl_type) 6190 { 6191 if (in_decl && (complain & tf_error)) 6192 { 6193 error ("type/value mismatch at argument %d in template " 6194 "parameter list for %qD", 6195 i + 1, in_decl); 6196 if (is_tmpl_type) 6197 error (" expected a type, got %qT", DECL_NAME (arg)); 6198 else 6199 error (" expected a class template, got %qT", orig_arg); 6200 } 6201 return error_mark_node; 6202 } 6203 6204 if (is_type) 6205 { 6206 if (requires_tmpl_type) 6207 { 6208 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg)) 6209 val = orig_arg; 6210 else if (TREE_CODE (TREE_TYPE (arg)) == UNBOUND_CLASS_TEMPLATE) 6211 /* The number of argument required is not known yet. 6212 Just accept it for now. */ 6213 val = TREE_TYPE (arg); 6214 else 6215 { 6216 tree parmparm = DECL_INNERMOST_TEMPLATE_PARMS (parm); 6217 tree argparm; 6218 6219 argparm = DECL_INNERMOST_TEMPLATE_PARMS (arg); 6220 6221 if (coerce_template_template_parms (parmparm, argparm, 6222 complain, in_decl, 6223 args)) 6224 { 6225 val = arg; 6226 6227 /* TEMPLATE_TEMPLATE_PARM node is preferred over 6228 TEMPLATE_DECL. */ 6229 if (val != error_mark_node) 6230 { 6231 if (DECL_TEMPLATE_TEMPLATE_PARM_P (val)) 6232 val = TREE_TYPE (val); 6233 if (TREE_CODE (orig_arg) == TYPE_PACK_EXPANSION) 6234 val = make_pack_expansion (val); 6235 } 6236 } 6237 else 6238 { 6239 if (in_decl && (complain & tf_error)) 6240 { 6241 error ("type/value mismatch at argument %d in " 6242 "template parameter list for %qD", 6243 i + 1, in_decl); 6244 error (" expected a template of type %qD, got %qT", 6245 parm, orig_arg); 6246 } 6247 6248 val = error_mark_node; 6249 } 6250 } 6251 } 6252 else 6253 val = orig_arg; 6254 /* We only form one instance of each template specialization. 6255 Therefore, if we use a non-canonical variant (i.e., a 6256 typedef), any future messages referring to the type will use 6257 the typedef, which is confusing if those future uses do not 6258 themselves also use the typedef. */ 6259 if (TYPE_P (val)) 6260 val = canonicalize_type_argument (val, complain); 6261 } 6262 else 6263 { 6264 tree t = tsubst (TREE_TYPE (parm), args, complain, in_decl); 6265 6266 if (invalid_nontype_parm_type_p (t, complain)) 6267 return error_mark_node; 6268 6269 if (template_parameter_pack_p (parm) && ARGUMENT_PACK_P (orig_arg)) 6270 { 6271 if (same_type_p (t, TREE_TYPE (orig_arg))) 6272 val = orig_arg; 6273 else 6274 { 6275 /* Not sure if this is reachable, but it doesn't hurt 6276 to be robust. */ 6277 error ("type mismatch in nontype parameter pack"); 6278 val = error_mark_node; 6279 } 6280 } 6281 else if (!uses_template_parms (orig_arg) && !uses_template_parms (t)) 6282 /* We used to call digest_init here. However, digest_init 6283 will report errors, which we don't want when complain 6284 is zero. More importantly, digest_init will try too 6285 hard to convert things: for example, `0' should not be 6286 converted to pointer type at this point according to 6287 the standard. Accepting this is not merely an 6288 extension, since deciding whether or not these 6289 conversions can occur is part of determining which 6290 function template to call, or whether a given explicit 6291 argument specification is valid. */ 6292 val = convert_nontype_argument (t, orig_arg, complain); 6293 else 6294 val = strip_typedefs_expr (orig_arg); 6295 6296 if (val == NULL_TREE) 6297 val = error_mark_node; 6298 else if (val == error_mark_node && (complain & tf_error)) 6299 error ("could not convert template argument %qE to %qT", orig_arg, t); 6300 6301 if (TREE_CODE (val) == SCOPE_REF) 6302 { 6303 /* Strip typedefs from the SCOPE_REF. */ 6304 tree type = canonicalize_type_argument (TREE_TYPE (val), complain); 6305 tree scope = canonicalize_type_argument (TREE_OPERAND (val, 0), 6306 complain); 6307 val = build_qualified_name (type, scope, TREE_OPERAND (val, 1), 6308 QUALIFIED_NAME_IS_TEMPLATE (val)); 6309 } 6310 } 6311 6312 return val; 6313 } 6314 6315 /* Coerces the remaining template arguments in INNER_ARGS (from 6316 ARG_IDX to the end) into the parameter pack at PARM_IDX in PARMS. 6317 Returns the coerced argument pack. PARM_IDX is the position of this 6318 parameter in the template parameter list. ARGS is the original 6319 template argument list. */ 6320 static tree 6321 coerce_template_parameter_pack (tree parms, 6322 int parm_idx, 6323 tree args, 6324 tree inner_args, 6325 int arg_idx, 6326 tree new_args, 6327 int* lost, 6328 tree in_decl, 6329 tsubst_flags_t complain) 6330 { 6331 tree parm = TREE_VEC_ELT (parms, parm_idx); 6332 int nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0; 6333 tree packed_args; 6334 tree argument_pack; 6335 tree packed_types = NULL_TREE; 6336 6337 if (arg_idx > nargs) 6338 arg_idx = nargs; 6339 6340 packed_args = make_tree_vec (nargs - arg_idx); 6341 6342 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL 6343 && uses_parameter_packs (TREE_TYPE (TREE_VALUE (parm)))) 6344 { 6345 /* When the template parameter is a non-type template 6346 parameter pack whose type uses parameter packs, we need 6347 to look at each of the template arguments 6348 separately. Build a vector of the types for these 6349 non-type template parameters in PACKED_TYPES. */ 6350 tree expansion 6351 = make_pack_expansion (TREE_TYPE (TREE_VALUE (parm))); 6352 packed_types = tsubst_pack_expansion (expansion, args, 6353 complain, in_decl); 6354 6355 if (packed_types == error_mark_node) 6356 return error_mark_node; 6357 6358 /* Check that we have the right number of arguments. */ 6359 if (arg_idx < nargs 6360 && !PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx)) 6361 && nargs - arg_idx != TREE_VEC_LENGTH (packed_types)) 6362 { 6363 int needed_parms 6364 = TREE_VEC_LENGTH (parms) - 1 + TREE_VEC_LENGTH (packed_types); 6365 error ("wrong number of template arguments (%d, should be %d)", 6366 nargs, needed_parms); 6367 return error_mark_node; 6368 } 6369 6370 /* If we aren't able to check the actual arguments now 6371 (because they haven't been expanded yet), we can at least 6372 verify that all of the types used for the non-type 6373 template parameter pack are, in fact, valid for non-type 6374 template parameters. */ 6375 if (arg_idx < nargs 6376 && PACK_EXPANSION_P (TREE_VEC_ELT (inner_args, arg_idx))) 6377 { 6378 int j, len = TREE_VEC_LENGTH (packed_types); 6379 for (j = 0; j < len; ++j) 6380 { 6381 tree t = TREE_VEC_ELT (packed_types, j); 6382 if (invalid_nontype_parm_type_p (t, complain)) 6383 return error_mark_node; 6384 } 6385 } 6386 } 6387 6388 /* Convert the remaining arguments, which will be a part of the 6389 parameter pack "parm". */ 6390 for (; arg_idx < nargs; ++arg_idx) 6391 { 6392 tree arg = TREE_VEC_ELT (inner_args, arg_idx); 6393 tree actual_parm = TREE_VALUE (parm); 6394 6395 if (packed_types && !PACK_EXPANSION_P (arg)) 6396 { 6397 /* When we have a vector of types (corresponding to the 6398 non-type template parameter pack that uses parameter 6399 packs in its type, as mention above), and the 6400 argument is not an expansion (which expands to a 6401 currently unknown number of arguments), clone the 6402 parm and give it the next type in PACKED_TYPES. */ 6403 actual_parm = copy_node (actual_parm); 6404 TREE_TYPE (actual_parm) = 6405 TREE_VEC_ELT (packed_types, arg_idx - parm_idx); 6406 } 6407 6408 if (arg != error_mark_node) 6409 arg = convert_template_argument (actual_parm, 6410 arg, new_args, complain, parm_idx, 6411 in_decl); 6412 if (arg == error_mark_node) 6413 (*lost)++; 6414 TREE_VEC_ELT (packed_args, arg_idx - parm_idx) = arg; 6415 } 6416 6417 if (TREE_CODE (TREE_VALUE (parm)) == TYPE_DECL 6418 || TREE_CODE (TREE_VALUE (parm)) == TEMPLATE_DECL) 6419 argument_pack = cxx_make_type (TYPE_ARGUMENT_PACK); 6420 else 6421 { 6422 argument_pack = make_node (NONTYPE_ARGUMENT_PACK); 6423 TREE_TYPE (argument_pack) 6424 = tsubst (TREE_TYPE (TREE_VALUE (parm)), new_args, complain, in_decl); 6425 TREE_CONSTANT (argument_pack) = 1; 6426 } 6427 6428 SET_ARGUMENT_PACK_ARGS (argument_pack, packed_args); 6429 #ifdef ENABLE_CHECKING 6430 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (packed_args, 6431 TREE_VEC_LENGTH (packed_args)); 6432 #endif 6433 return argument_pack; 6434 } 6435 6436 /* Returns true if the template argument vector ARGS contains 6437 any pack expansions, false otherwise. */ 6438 6439 static bool 6440 any_pack_expanson_args_p (tree args) 6441 { 6442 int i; 6443 if (args) 6444 for (i = 0; i < TREE_VEC_LENGTH (args); ++i) 6445 if (PACK_EXPANSION_P (TREE_VEC_ELT (args, i))) 6446 return true; 6447 return false; 6448 } 6449 6450 /* Convert all template arguments to their appropriate types, and 6451 return a vector containing the innermost resulting template 6452 arguments. If any error occurs, return error_mark_node. Error and 6453 warning messages are issued under control of COMPLAIN. 6454 6455 If REQUIRE_ALL_ARGS is false, argument deduction will be performed 6456 for arguments not specified in ARGS. Otherwise, if 6457 USE_DEFAULT_ARGS is true, default arguments will be used to fill in 6458 unspecified arguments. If REQUIRE_ALL_ARGS is true, but 6459 USE_DEFAULT_ARGS is false, then all arguments must be specified in 6460 ARGS. */ 6461 6462 static tree 6463 coerce_template_parms (tree parms, 6464 tree args, 6465 tree in_decl, 6466 tsubst_flags_t complain, 6467 bool require_all_args, 6468 bool use_default_args) 6469 { 6470 int nparms, nargs, parm_idx, arg_idx, lost = 0; 6471 tree inner_args; 6472 tree new_args; 6473 tree new_inner_args; 6474 int saved_unevaluated_operand; 6475 int saved_inhibit_evaluation_warnings; 6476 6477 /* When used as a boolean value, indicates whether this is a 6478 variadic template parameter list. Since it's an int, we can also 6479 subtract it from nparms to get the number of non-variadic 6480 parameters. */ 6481 int variadic_p = 0; 6482 int post_variadic_parms = 0; 6483 6484 if (args == error_mark_node) 6485 return error_mark_node; 6486 6487 nparms = TREE_VEC_LENGTH (parms); 6488 6489 /* Determine if there are any parameter packs. */ 6490 for (parm_idx = 0; parm_idx < nparms; ++parm_idx) 6491 { 6492 tree tparm = TREE_VALUE (TREE_VEC_ELT (parms, parm_idx)); 6493 if (variadic_p) 6494 ++post_variadic_parms; 6495 if (template_parameter_pack_p (tparm)) 6496 ++variadic_p; 6497 } 6498 6499 inner_args = INNERMOST_TEMPLATE_ARGS (args); 6500 /* If there are no parameters that follow a parameter pack, we need to 6501 expand any argument packs so that we can deduce a parameter pack from 6502 some non-packed args followed by an argument pack, as in variadic85.C. 6503 If there are such parameters, we need to leave argument packs intact 6504 so the arguments are assigned properly. This can happen when dealing 6505 with a nested class inside a partial specialization of a class 6506 template, as in variadic92.C, or when deducing a template parameter pack 6507 from a sub-declarator, as in variadic114.C. */ 6508 if (!post_variadic_parms) 6509 inner_args = expand_template_argument_pack (inner_args); 6510 6511 nargs = inner_args ? NUM_TMPL_ARGS (inner_args) : 0; 6512 if ((nargs > nparms && !variadic_p) 6513 || (nargs < nparms - variadic_p 6514 && require_all_args 6515 && !any_pack_expanson_args_p (inner_args) 6516 && (!use_default_args 6517 || (TREE_VEC_ELT (parms, nargs) != error_mark_node 6518 && !TREE_PURPOSE (TREE_VEC_ELT (parms, nargs)))))) 6519 { 6520 if (complain & tf_error) 6521 { 6522 if (variadic_p) 6523 { 6524 nparms -= variadic_p; 6525 error ("wrong number of template arguments " 6526 "(%d, should be %d or more)", nargs, nparms); 6527 } 6528 else 6529 error ("wrong number of template arguments " 6530 "(%d, should be %d)", nargs, nparms); 6531 6532 if (in_decl) 6533 error ("provided for %q+D", in_decl); 6534 } 6535 6536 return error_mark_node; 6537 } 6538 6539 /* We need to evaluate the template arguments, even though this 6540 template-id may be nested within a "sizeof". */ 6541 saved_unevaluated_operand = cp_unevaluated_operand; 6542 cp_unevaluated_operand = 0; 6543 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings; 6544 c_inhibit_evaluation_warnings = 0; 6545 new_inner_args = make_tree_vec (nparms); 6546 new_args = add_outermost_template_args (args, new_inner_args); 6547 for (parm_idx = 0, arg_idx = 0; parm_idx < nparms; parm_idx++, arg_idx++) 6548 { 6549 tree arg; 6550 tree parm; 6551 6552 /* Get the Ith template parameter. */ 6553 parm = TREE_VEC_ELT (parms, parm_idx); 6554 6555 if (parm == error_mark_node) 6556 { 6557 TREE_VEC_ELT (new_inner_args, arg_idx) = error_mark_node; 6558 continue; 6559 } 6560 6561 /* Calculate the next argument. */ 6562 if (arg_idx < nargs) 6563 arg = TREE_VEC_ELT (inner_args, arg_idx); 6564 else 6565 arg = NULL_TREE; 6566 6567 if (template_parameter_pack_p (TREE_VALUE (parm)) 6568 && !(arg && ARGUMENT_PACK_P (arg))) 6569 { 6570 /* All remaining arguments will be placed in the 6571 template parameter pack PARM. */ 6572 arg = coerce_template_parameter_pack (parms, parm_idx, args, 6573 inner_args, arg_idx, 6574 new_args, &lost, 6575 in_decl, complain); 6576 6577 /* Store this argument. */ 6578 if (arg == error_mark_node) 6579 lost++; 6580 TREE_VEC_ELT (new_inner_args, parm_idx) = arg; 6581 6582 /* We are done with all of the arguments. */ 6583 arg_idx = nargs; 6584 6585 continue; 6586 } 6587 else if (arg) 6588 { 6589 if (PACK_EXPANSION_P (arg)) 6590 { 6591 /* We don't know how many args we have yet, just 6592 use the unconverted ones for now. */ 6593 new_inner_args = inner_args; 6594 break; 6595 } 6596 } 6597 else if (require_all_args) 6598 { 6599 /* There must be a default arg in this case. */ 6600 arg = tsubst_template_arg (TREE_PURPOSE (parm), new_args, 6601 complain, in_decl); 6602 /* The position of the first default template argument, 6603 is also the number of non-defaulted arguments in NEW_INNER_ARGS. 6604 Record that. */ 6605 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args)) 6606 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, arg_idx); 6607 } 6608 else 6609 break; 6610 6611 if (arg == error_mark_node) 6612 { 6613 if (complain & tf_error) 6614 error ("template argument %d is invalid", arg_idx + 1); 6615 } 6616 else if (!arg) 6617 /* This only occurs if there was an error in the template 6618 parameter list itself (which we would already have 6619 reported) that we are trying to recover from, e.g., a class 6620 template with a parameter list such as 6621 template<typename..., typename>. */ 6622 ++lost; 6623 else 6624 arg = convert_template_argument (TREE_VALUE (parm), 6625 arg, new_args, complain, 6626 parm_idx, in_decl); 6627 6628 if (arg == error_mark_node) 6629 lost++; 6630 TREE_VEC_ELT (new_inner_args, arg_idx) = arg; 6631 } 6632 cp_unevaluated_operand = saved_unevaluated_operand; 6633 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings; 6634 6635 if (lost) 6636 return error_mark_node; 6637 6638 #ifdef ENABLE_CHECKING 6639 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args)) 6640 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (new_inner_args, 6641 TREE_VEC_LENGTH (new_inner_args)); 6642 #endif 6643 6644 return new_inner_args; 6645 } 6646 6647 /* Returns 1 if template args OT and NT are equivalent. */ 6648 6649 static int 6650 template_args_equal (tree ot, tree nt) 6651 { 6652 if (nt == ot) 6653 return 1; 6654 if (nt == NULL_TREE || ot == NULL_TREE) 6655 return false; 6656 6657 if (TREE_CODE (nt) == TREE_VEC) 6658 /* For member templates */ 6659 return TREE_CODE (ot) == TREE_VEC && comp_template_args (ot, nt); 6660 else if (PACK_EXPANSION_P (ot)) 6661 return (PACK_EXPANSION_P (nt) 6662 && template_args_equal (PACK_EXPANSION_PATTERN (ot), 6663 PACK_EXPANSION_PATTERN (nt)) 6664 && template_args_equal (PACK_EXPANSION_EXTRA_ARGS (ot), 6665 PACK_EXPANSION_EXTRA_ARGS (nt))); 6666 else if (ARGUMENT_PACK_P (ot)) 6667 { 6668 int i, len; 6669 tree opack, npack; 6670 6671 if (!ARGUMENT_PACK_P (nt)) 6672 return 0; 6673 6674 opack = ARGUMENT_PACK_ARGS (ot); 6675 npack = ARGUMENT_PACK_ARGS (nt); 6676 len = TREE_VEC_LENGTH (opack); 6677 if (TREE_VEC_LENGTH (npack) != len) 6678 return 0; 6679 for (i = 0; i < len; ++i) 6680 if (!template_args_equal (TREE_VEC_ELT (opack, i), 6681 TREE_VEC_ELT (npack, i))) 6682 return 0; 6683 return 1; 6684 } 6685 else if (ot && TREE_CODE (ot) == ARGUMENT_PACK_SELECT) 6686 { 6687 /* We get here probably because we are in the middle of substituting 6688 into the pattern of a pack expansion. In that case the 6689 ARGUMENT_PACK_SELECT temporarily replaces the pack argument we are 6690 interested in. So we want to use the initial pack argument for 6691 the comparison. */ 6692 ot = ARGUMENT_PACK_SELECT_FROM_PACK (ot); 6693 if (nt && TREE_CODE (nt) == ARGUMENT_PACK_SELECT) 6694 nt = ARGUMENT_PACK_SELECT_FROM_PACK (nt); 6695 return template_args_equal (ot, nt); 6696 } 6697 else if (TYPE_P (nt)) 6698 return TYPE_P (ot) && same_type_p (ot, nt); 6699 else if (TREE_CODE (ot) == TREE_VEC || TYPE_P (ot)) 6700 return 0; 6701 else 6702 return cp_tree_equal (ot, nt); 6703 } 6704 6705 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets of 6706 template arguments. Returns 0 otherwise, and updates OLDARG_PTR and 6707 NEWARG_PTR with the offending arguments if they are non-NULL. */ 6708 6709 static int 6710 comp_template_args_with_info (tree oldargs, tree newargs, 6711 tree *oldarg_ptr, tree *newarg_ptr) 6712 { 6713 int i; 6714 6715 if (oldargs == newargs) 6716 return 1; 6717 6718 if (!oldargs || !newargs) 6719 return 0; 6720 6721 if (TREE_VEC_LENGTH (oldargs) != TREE_VEC_LENGTH (newargs)) 6722 return 0; 6723 6724 for (i = 0; i < TREE_VEC_LENGTH (oldargs); ++i) 6725 { 6726 tree nt = TREE_VEC_ELT (newargs, i); 6727 tree ot = TREE_VEC_ELT (oldargs, i); 6728 6729 if (! template_args_equal (ot, nt)) 6730 { 6731 if (oldarg_ptr != NULL) 6732 *oldarg_ptr = ot; 6733 if (newarg_ptr != NULL) 6734 *newarg_ptr = nt; 6735 return 0; 6736 } 6737 } 6738 return 1; 6739 } 6740 6741 /* Returns 1 iff the OLDARGS and NEWARGS are in fact identical sets 6742 of template arguments. Returns 0 otherwise. */ 6743 6744 int 6745 comp_template_args (tree oldargs, tree newargs) 6746 { 6747 return comp_template_args_with_info (oldargs, newargs, NULL, NULL); 6748 } 6749 6750 static void 6751 add_pending_template (tree d) 6752 { 6753 tree ti = (TYPE_P (d) 6754 ? CLASSTYPE_TEMPLATE_INFO (d) 6755 : DECL_TEMPLATE_INFO (d)); 6756 struct pending_template *pt; 6757 int level; 6758 6759 if (TI_PENDING_TEMPLATE_FLAG (ti)) 6760 return; 6761 6762 /* We are called both from instantiate_decl, where we've already had a 6763 tinst_level pushed, and instantiate_template, where we haven't. 6764 Compensate. */ 6765 level = !current_tinst_level || current_tinst_level->decl != d; 6766 6767 if (level) 6768 push_tinst_level (d); 6769 6770 pt = ggc_alloc_pending_template (); 6771 pt->next = NULL; 6772 pt->tinst = current_tinst_level; 6773 if (last_pending_template) 6774 last_pending_template->next = pt; 6775 else 6776 pending_templates = pt; 6777 6778 last_pending_template = pt; 6779 6780 TI_PENDING_TEMPLATE_FLAG (ti) = 1; 6781 6782 if (level) 6783 pop_tinst_level (); 6784 } 6785 6786 6787 /* Return a TEMPLATE_ID_EXPR corresponding to the indicated FNS and 6788 ARGLIST. Valid choices for FNS are given in the cp-tree.def 6789 documentation for TEMPLATE_ID_EXPR. */ 6790 6791 tree 6792 lookup_template_function (tree fns, tree arglist) 6793 { 6794 tree type; 6795 6796 if (fns == error_mark_node || arglist == error_mark_node) 6797 return error_mark_node; 6798 6799 gcc_assert (!arglist || TREE_CODE (arglist) == TREE_VEC); 6800 6801 if (!is_overloaded_fn (fns) && TREE_CODE (fns) != IDENTIFIER_NODE) 6802 { 6803 error ("%q#D is not a function template", fns); 6804 return error_mark_node; 6805 } 6806 6807 if (BASELINK_P (fns)) 6808 { 6809 BASELINK_FUNCTIONS (fns) = build2 (TEMPLATE_ID_EXPR, 6810 unknown_type_node, 6811 BASELINK_FUNCTIONS (fns), 6812 arglist); 6813 return fns; 6814 } 6815 6816 type = TREE_TYPE (fns); 6817 if (TREE_CODE (fns) == OVERLOAD || !type) 6818 type = unknown_type_node; 6819 6820 return build2 (TEMPLATE_ID_EXPR, type, fns, arglist); 6821 } 6822 6823 /* Within the scope of a template class S<T>, the name S gets bound 6824 (in build_self_reference) to a TYPE_DECL for the class, not a 6825 TEMPLATE_DECL. If DECL is a TYPE_DECL for current_class_type, 6826 or one of its enclosing classes, and that type is a template, 6827 return the associated TEMPLATE_DECL. Otherwise, the original 6828 DECL is returned. 6829 6830 Also handle the case when DECL is a TREE_LIST of ambiguous 6831 injected-class-names from different bases. */ 6832 6833 tree 6834 maybe_get_template_decl_from_type_decl (tree decl) 6835 { 6836 if (decl == NULL_TREE) 6837 return decl; 6838 6839 /* DR 176: A lookup that finds an injected-class-name (10.2 6840 [class.member.lookup]) can result in an ambiguity in certain cases 6841 (for example, if it is found in more than one base class). If all of 6842 the injected-class-names that are found refer to specializations of 6843 the same class template, and if the name is followed by a 6844 template-argument-list, the reference refers to the class template 6845 itself and not a specialization thereof, and is not ambiguous. */ 6846 if (TREE_CODE (decl) == TREE_LIST) 6847 { 6848 tree t, tmpl = NULL_TREE; 6849 for (t = decl; t; t = TREE_CHAIN (t)) 6850 { 6851 tree elt = maybe_get_template_decl_from_type_decl (TREE_VALUE (t)); 6852 if (!tmpl) 6853 tmpl = elt; 6854 else if (tmpl != elt) 6855 break; 6856 } 6857 if (tmpl && t == NULL_TREE) 6858 return tmpl; 6859 else 6860 return decl; 6861 } 6862 6863 return (decl != NULL_TREE 6864 && DECL_SELF_REFERENCE_P (decl) 6865 && CLASSTYPE_TEMPLATE_INFO (TREE_TYPE (decl))) 6866 ? CLASSTYPE_TI_TEMPLATE (TREE_TYPE (decl)) : decl; 6867 } 6868 6869 /* Given an IDENTIFIER_NODE (type TEMPLATE_DECL) and a chain of 6870 parameters, find the desired type. 6871 6872 D1 is the PTYPENAME terminal, and ARGLIST is the list of arguments. 6873 6874 IN_DECL, if non-NULL, is the template declaration we are trying to 6875 instantiate. 6876 6877 If ENTERING_SCOPE is nonzero, we are about to enter the scope of 6878 the class we are looking up. 6879 6880 Issue error and warning messages under control of COMPLAIN. 6881 6882 If the template class is really a local class in a template 6883 function, then the FUNCTION_CONTEXT is the function in which it is 6884 being instantiated. 6885 6886 ??? Note that this function is currently called *twice* for each 6887 template-id: the first time from the parser, while creating the 6888 incomplete type (finish_template_type), and the second type during the 6889 real instantiation (instantiate_template_class). This is surely something 6890 that we want to avoid. It also causes some problems with argument 6891 coercion (see convert_nontype_argument for more information on this). */ 6892 6893 static tree 6894 lookup_template_class_1 (tree d1, tree arglist, tree in_decl, tree context, 6895 int entering_scope, tsubst_flags_t complain) 6896 { 6897 tree templ = NULL_TREE, parmlist; 6898 tree t; 6899 void **slot; 6900 spec_entry *entry; 6901 spec_entry elt; 6902 hashval_t hash; 6903 6904 if (TREE_CODE (d1) == IDENTIFIER_NODE) 6905 { 6906 tree value = innermost_non_namespace_value (d1); 6907 if (value && DECL_TEMPLATE_TEMPLATE_PARM_P (value)) 6908 templ = value; 6909 else 6910 { 6911 if (context) 6912 push_decl_namespace (context); 6913 templ = lookup_name (d1); 6914 templ = maybe_get_template_decl_from_type_decl (templ); 6915 if (context) 6916 pop_decl_namespace (); 6917 } 6918 if (templ) 6919 context = DECL_CONTEXT (templ); 6920 } 6921 else if (TREE_CODE (d1) == TYPE_DECL && MAYBE_CLASS_TYPE_P (TREE_TYPE (d1))) 6922 { 6923 tree type = TREE_TYPE (d1); 6924 6925 /* If we are declaring a constructor, say A<T>::A<T>, we will get 6926 an implicit typename for the second A. Deal with it. */ 6927 if (TREE_CODE (type) == TYPENAME_TYPE && TREE_TYPE (type)) 6928 type = TREE_TYPE (type); 6929 6930 if (CLASSTYPE_TEMPLATE_INFO (type)) 6931 { 6932 templ = CLASSTYPE_TI_TEMPLATE (type); 6933 d1 = DECL_NAME (templ); 6934 } 6935 } 6936 else if (TREE_CODE (d1) == ENUMERAL_TYPE 6937 || (TYPE_P (d1) && MAYBE_CLASS_TYPE_P (d1))) 6938 { 6939 templ = TYPE_TI_TEMPLATE (d1); 6940 d1 = DECL_NAME (templ); 6941 } 6942 else if (TREE_CODE (d1) == TEMPLATE_DECL 6943 && DECL_TEMPLATE_RESULT (d1) 6944 && TREE_CODE (DECL_TEMPLATE_RESULT (d1)) == TYPE_DECL) 6945 { 6946 templ = d1; 6947 d1 = DECL_NAME (templ); 6948 context = DECL_CONTEXT (templ); 6949 } 6950 6951 /* Issue an error message if we didn't find a template. */ 6952 if (! templ) 6953 { 6954 if (complain & tf_error) 6955 error ("%qT is not a template", d1); 6956 return error_mark_node; 6957 } 6958 6959 if (TREE_CODE (templ) != TEMPLATE_DECL 6960 /* Make sure it's a user visible template, if it was named by 6961 the user. */ 6962 || ((complain & tf_user) && !DECL_TEMPLATE_PARM_P (templ) 6963 && !PRIMARY_TEMPLATE_P (templ))) 6964 { 6965 if (complain & tf_error) 6966 { 6967 error ("non-template type %qT used as a template", d1); 6968 if (in_decl) 6969 error ("for template declaration %q+D", in_decl); 6970 } 6971 return error_mark_node; 6972 } 6973 6974 complain &= ~tf_user; 6975 6976 if (DECL_TEMPLATE_TEMPLATE_PARM_P (templ)) 6977 { 6978 /* Create a new TEMPLATE_DECL and TEMPLATE_TEMPLATE_PARM node to store 6979 template arguments */ 6980 6981 tree parm; 6982 tree arglist2; 6983 tree outer; 6984 6985 parmlist = DECL_INNERMOST_TEMPLATE_PARMS (templ); 6986 6987 /* Consider an example where a template template parameter declared as 6988 6989 template <class T, class U = std::allocator<T> > class TT 6990 6991 The template parameter level of T and U are one level larger than 6992 of TT. To proper process the default argument of U, say when an 6993 instantiation `TT<int>' is seen, we need to build the full 6994 arguments containing {int} as the innermost level. Outer levels, 6995 available when not appearing as default template argument, can be 6996 obtained from the arguments of the enclosing template. 6997 6998 Suppose that TT is later substituted with std::vector. The above 6999 instantiation is `TT<int, std::allocator<T> >' with TT at 7000 level 1, and T at level 2, while the template arguments at level 1 7001 becomes {std::vector} and the inner level 2 is {int}. */ 7002 7003 outer = DECL_CONTEXT (templ); 7004 if (outer) 7005 outer = TI_ARGS (get_template_info (DECL_TEMPLATE_RESULT (outer))); 7006 else if (current_template_parms) 7007 /* This is an argument of the current template, so we haven't set 7008 DECL_CONTEXT yet. */ 7009 outer = current_template_args (); 7010 7011 if (outer) 7012 arglist = add_to_template_args (outer, arglist); 7013 7014 arglist2 = coerce_template_parms (parmlist, arglist, templ, 7015 complain, 7016 /*require_all_args=*/true, 7017 /*use_default_args=*/true); 7018 if (arglist2 == error_mark_node 7019 || (!uses_template_parms (arglist2) 7020 && check_instantiated_args (templ, arglist2, complain))) 7021 return error_mark_node; 7022 7023 parm = bind_template_template_parm (TREE_TYPE (templ), arglist2); 7024 return parm; 7025 } 7026 else 7027 { 7028 tree template_type = TREE_TYPE (templ); 7029 tree gen_tmpl; 7030 tree type_decl; 7031 tree found = NULL_TREE; 7032 int arg_depth; 7033 int parm_depth; 7034 int is_dependent_type; 7035 int use_partial_inst_tmpl = false; 7036 7037 if (template_type == error_mark_node) 7038 /* An error occured while building the template TEMPL, and a 7039 diagnostic has most certainly been emitted for that 7040 already. Let's propagate that error. */ 7041 return error_mark_node; 7042 7043 gen_tmpl = most_general_template (templ); 7044 parmlist = DECL_TEMPLATE_PARMS (gen_tmpl); 7045 parm_depth = TMPL_PARMS_DEPTH (parmlist); 7046 arg_depth = TMPL_ARGS_DEPTH (arglist); 7047 7048 if (arg_depth == 1 && parm_depth > 1) 7049 { 7050 /* We've been given an incomplete set of template arguments. 7051 For example, given: 7052 7053 template <class T> struct S1 { 7054 template <class U> struct S2 {}; 7055 template <class U> struct S2<U*> {}; 7056 }; 7057 7058 we will be called with an ARGLIST of `U*', but the 7059 TEMPLATE will be `template <class T> template 7060 <class U> struct S1<T>::S2'. We must fill in the missing 7061 arguments. */ 7062 arglist 7063 = add_outermost_template_args (TYPE_TI_ARGS (TREE_TYPE (templ)), 7064 arglist); 7065 arg_depth = TMPL_ARGS_DEPTH (arglist); 7066 } 7067 7068 /* Now we should have enough arguments. */ 7069 gcc_assert (parm_depth == arg_depth); 7070 7071 /* From here on, we're only interested in the most general 7072 template. */ 7073 7074 /* Calculate the BOUND_ARGS. These will be the args that are 7075 actually tsubst'd into the definition to create the 7076 instantiation. */ 7077 if (parm_depth > 1) 7078 { 7079 /* We have multiple levels of arguments to coerce, at once. */ 7080 int i; 7081 int saved_depth = TMPL_ARGS_DEPTH (arglist); 7082 7083 tree bound_args = make_tree_vec (parm_depth); 7084 7085 for (i = saved_depth, 7086 t = DECL_TEMPLATE_PARMS (gen_tmpl); 7087 i > 0 && t != NULL_TREE; 7088 --i, t = TREE_CHAIN (t)) 7089 { 7090 tree a; 7091 if (i == saved_depth) 7092 a = coerce_template_parms (TREE_VALUE (t), 7093 arglist, gen_tmpl, 7094 complain, 7095 /*require_all_args=*/true, 7096 /*use_default_args=*/true); 7097 else 7098 /* Outer levels should have already been coerced. */ 7099 a = TMPL_ARGS_LEVEL (arglist, i); 7100 7101 /* Don't process further if one of the levels fails. */ 7102 if (a == error_mark_node) 7103 { 7104 /* Restore the ARGLIST to its full size. */ 7105 TREE_VEC_LENGTH (arglist) = saved_depth; 7106 return error_mark_node; 7107 } 7108 7109 SET_TMPL_ARGS_LEVEL (bound_args, i, a); 7110 7111 /* We temporarily reduce the length of the ARGLIST so 7112 that coerce_template_parms will see only the arguments 7113 corresponding to the template parameters it is 7114 examining. */ 7115 TREE_VEC_LENGTH (arglist)--; 7116 } 7117 7118 /* Restore the ARGLIST to its full size. */ 7119 TREE_VEC_LENGTH (arglist) = saved_depth; 7120 7121 arglist = bound_args; 7122 } 7123 else 7124 arglist 7125 = coerce_template_parms (INNERMOST_TEMPLATE_PARMS (parmlist), 7126 INNERMOST_TEMPLATE_ARGS (arglist), 7127 gen_tmpl, 7128 complain, 7129 /*require_all_args=*/true, 7130 /*use_default_args=*/true); 7131 7132 if (arglist == error_mark_node) 7133 /* We were unable to bind the arguments. */ 7134 return error_mark_node; 7135 7136 /* In the scope of a template class, explicit references to the 7137 template class refer to the type of the template, not any 7138 instantiation of it. For example, in: 7139 7140 template <class T> class C { void f(C<T>); } 7141 7142 the `C<T>' is just the same as `C'. Outside of the 7143 class, however, such a reference is an instantiation. */ 7144 if ((entering_scope 7145 || !PRIMARY_TEMPLATE_P (gen_tmpl) 7146 || currently_open_class (template_type)) 7147 /* comp_template_args is expensive, check it last. */ 7148 && comp_template_args (TYPE_TI_ARGS (template_type), 7149 arglist)) 7150 return template_type; 7151 7152 /* If we already have this specialization, return it. */ 7153 elt.tmpl = gen_tmpl; 7154 elt.args = arglist; 7155 hash = hash_specialization (&elt); 7156 entry = (spec_entry *) htab_find_with_hash (type_specializations, 7157 &elt, hash); 7158 7159 if (entry) 7160 return entry->spec; 7161 7162 is_dependent_type = uses_template_parms (arglist); 7163 7164 /* If the deduced arguments are invalid, then the binding 7165 failed. */ 7166 if (!is_dependent_type 7167 && check_instantiated_args (gen_tmpl, 7168 INNERMOST_TEMPLATE_ARGS (arglist), 7169 complain)) 7170 return error_mark_node; 7171 7172 if (!is_dependent_type 7173 && !PRIMARY_TEMPLATE_P (gen_tmpl) 7174 && !LAMBDA_TYPE_P (TREE_TYPE (gen_tmpl)) 7175 && TREE_CODE (CP_DECL_CONTEXT (gen_tmpl)) == NAMESPACE_DECL) 7176 { 7177 found = xref_tag_from_type (TREE_TYPE (gen_tmpl), 7178 DECL_NAME (gen_tmpl), 7179 /*tag_scope=*/ts_global); 7180 return found; 7181 } 7182 7183 context = tsubst (DECL_CONTEXT (gen_tmpl), arglist, 7184 complain, in_decl); 7185 if (context == error_mark_node) 7186 return error_mark_node; 7187 7188 if (!context) 7189 context = global_namespace; 7190 7191 /* Create the type. */ 7192 if (TREE_CODE (template_type) == ENUMERAL_TYPE) 7193 { 7194 if (!is_dependent_type) 7195 { 7196 set_current_access_from_decl (TYPE_NAME (template_type)); 7197 t = start_enum (TYPE_IDENTIFIER (template_type), NULL_TREE, 7198 tsubst (ENUM_UNDERLYING_TYPE (template_type), 7199 arglist, complain, in_decl), 7200 SCOPED_ENUM_P (template_type), NULL); 7201 } 7202 else 7203 { 7204 /* We don't want to call start_enum for this type, since 7205 the values for the enumeration constants may involve 7206 template parameters. And, no one should be interested 7207 in the enumeration constants for such a type. */ 7208 t = cxx_make_type (ENUMERAL_TYPE); 7209 SET_SCOPED_ENUM_P (t, SCOPED_ENUM_P (template_type)); 7210 } 7211 SET_OPAQUE_ENUM_P (t, OPAQUE_ENUM_P (template_type)); 7212 ENUM_FIXED_UNDERLYING_TYPE_P (t) 7213 = ENUM_FIXED_UNDERLYING_TYPE_P (template_type); 7214 } 7215 else if (DECL_ALIAS_TEMPLATE_P (gen_tmpl)) 7216 { 7217 /* The user referred to a specialization of an alias 7218 template represented by GEN_TMPL. 7219 7220 [temp.alias]/2 says: 7221 7222 When a template-id refers to the specialization of an 7223 alias template, it is equivalent to the associated 7224 type obtained by substitution of its 7225 template-arguments for the template-parameters in the 7226 type-id of the alias template. */ 7227 7228 t = tsubst (TREE_TYPE (gen_tmpl), arglist, complain, in_decl); 7229 /* Note that the call above (by indirectly calling 7230 register_specialization in tsubst_decl) registers the 7231 TYPE_DECL representing the specialization of the alias 7232 template. So next time someone substitutes ARGLIST for 7233 the template parms into the alias template (GEN_TMPL), 7234 she'll get that TYPE_DECL back. */ 7235 7236 if (t == error_mark_node) 7237 return t; 7238 } 7239 else if (CLASS_TYPE_P (template_type)) 7240 { 7241 t = make_class_type (TREE_CODE (template_type)); 7242 CLASSTYPE_DECLARED_CLASS (t) 7243 = CLASSTYPE_DECLARED_CLASS (template_type); 7244 SET_CLASSTYPE_IMPLICIT_INSTANTIATION (t); 7245 TYPE_FOR_JAVA (t) = TYPE_FOR_JAVA (template_type); 7246 7247 /* A local class. Make sure the decl gets registered properly. */ 7248 if (context == current_function_decl) 7249 pushtag (DECL_NAME (gen_tmpl), t, /*tag_scope=*/ts_global); 7250 7251 if (comp_template_args (CLASSTYPE_TI_ARGS (template_type), arglist)) 7252 /* This instantiation is another name for the primary 7253 template type. Set the TYPE_CANONICAL field 7254 appropriately. */ 7255 TYPE_CANONICAL (t) = template_type; 7256 else if (any_template_arguments_need_structural_equality_p (arglist)) 7257 /* Some of the template arguments require structural 7258 equality testing, so this template class requires 7259 structural equality testing. */ 7260 SET_TYPE_STRUCTURAL_EQUALITY (t); 7261 } 7262 else 7263 gcc_unreachable (); 7264 7265 /* If we called start_enum or pushtag above, this information 7266 will already be set up. */ 7267 if (!TYPE_NAME (t)) 7268 { 7269 TYPE_CONTEXT (t) = FROB_CONTEXT (context); 7270 7271 type_decl = create_implicit_typedef (DECL_NAME (gen_tmpl), t); 7272 DECL_CONTEXT (type_decl) = TYPE_CONTEXT (t); 7273 DECL_SOURCE_LOCATION (type_decl) 7274 = DECL_SOURCE_LOCATION (TYPE_STUB_DECL (template_type)); 7275 } 7276 else 7277 type_decl = TYPE_NAME (t); 7278 7279 if (CLASS_TYPE_P (template_type)) 7280 { 7281 TREE_PRIVATE (type_decl) 7282 = TREE_PRIVATE (TYPE_STUB_DECL (template_type)); 7283 TREE_PROTECTED (type_decl) 7284 = TREE_PROTECTED (TYPE_STUB_DECL (template_type)); 7285 if (CLASSTYPE_VISIBILITY_SPECIFIED (template_type)) 7286 { 7287 DECL_VISIBILITY_SPECIFIED (type_decl) = 1; 7288 DECL_VISIBILITY (type_decl) = CLASSTYPE_VISIBILITY (template_type); 7289 } 7290 } 7291 7292 /* Let's consider the explicit specialization of a member 7293 of a class template specialization that is implicitely instantiated, 7294 e.g.: 7295 template<class T> 7296 struct S 7297 { 7298 template<class U> struct M {}; //#0 7299 }; 7300 7301 template<> 7302 template<> 7303 struct S<int>::M<char> //#1 7304 { 7305 int i; 7306 }; 7307 [temp.expl.spec]/4 says this is valid. 7308 7309 In this case, when we write: 7310 S<int>::M<char> m; 7311 7312 M is instantiated from the CLASSTYPE_TI_TEMPLATE of #1, not from 7313 the one of #0. 7314 7315 When we encounter #1, we want to store the partial instantiation 7316 of M (template<class T> S<int>::M<T>) in it's CLASSTYPE_TI_TEMPLATE. 7317 7318 For all cases other than this "explicit specialization of member of a 7319 class template", we just want to store the most general template into 7320 the CLASSTYPE_TI_TEMPLATE of M. 7321 7322 This case of "explicit specialization of member of a class template" 7323 only happens when: 7324 1/ the enclosing class is an instantiation of, and therefore not 7325 the same as, the context of the most general template, and 7326 2/ we aren't looking at the partial instantiation itself, i.e. 7327 the innermost arguments are not the same as the innermost parms of 7328 the most general template. 7329 7330 So it's only when 1/ and 2/ happens that we want to use the partial 7331 instantiation of the member template in lieu of its most general 7332 template. */ 7333 7334 if (PRIMARY_TEMPLATE_P (gen_tmpl) 7335 && TMPL_ARGS_HAVE_MULTIPLE_LEVELS (arglist) 7336 /* the enclosing class must be an instantiation... */ 7337 && CLASS_TYPE_P (context) 7338 && !same_type_p (context, DECL_CONTEXT (gen_tmpl))) 7339 { 7340 tree partial_inst_args; 7341 TREE_VEC_LENGTH (arglist)--; 7342 ++processing_template_decl; 7343 partial_inst_args = 7344 tsubst (INNERMOST_TEMPLATE_ARGS 7345 (TYPE_TI_ARGS (TREE_TYPE (gen_tmpl))), 7346 arglist, complain, NULL_TREE); 7347 --processing_template_decl; 7348 TREE_VEC_LENGTH (arglist)++; 7349 use_partial_inst_tmpl = 7350 /*...and we must not be looking at the partial instantiation 7351 itself. */ 7352 !comp_template_args (INNERMOST_TEMPLATE_ARGS (arglist), 7353 partial_inst_args); 7354 } 7355 7356 if (!use_partial_inst_tmpl) 7357 /* This case is easy; there are no member templates involved. */ 7358 found = gen_tmpl; 7359 else 7360 { 7361 /* This is a full instantiation of a member template. Find 7362 the partial instantiation of which this is an instance. */ 7363 7364 /* Temporarily reduce by one the number of levels in the ARGLIST 7365 so as to avoid comparing the last set of arguments. */ 7366 TREE_VEC_LENGTH (arglist)--; 7367 found = tsubst (gen_tmpl, arglist, complain, NULL_TREE); 7368 TREE_VEC_LENGTH (arglist)++; 7369 /* FOUND is either a proper class type, or an alias 7370 template specialization. In the later case, it's a 7371 TYPE_DECL, resulting from the substituting of arguments 7372 for parameters in the TYPE_DECL of the alias template 7373 done earlier. So be careful while getting the template 7374 of FOUND. */ 7375 found = TREE_CODE (found) == TYPE_DECL 7376 ? TYPE_TI_TEMPLATE (TREE_TYPE (found)) 7377 : CLASSTYPE_TI_TEMPLATE (found); 7378 } 7379 7380 SET_TYPE_TEMPLATE_INFO (t, build_template_info (found, arglist)); 7381 7382 elt.spec = t; 7383 slot = htab_find_slot_with_hash (type_specializations, 7384 &elt, hash, INSERT); 7385 entry = ggc_alloc_spec_entry (); 7386 *entry = elt; 7387 *slot = entry; 7388 7389 /* Note this use of the partial instantiation so we can check it 7390 later in maybe_process_partial_specialization. */ 7391 DECL_TEMPLATE_INSTANTIATIONS (templ) 7392 = tree_cons (arglist, t, 7393 DECL_TEMPLATE_INSTANTIATIONS (templ)); 7394 7395 if (TREE_CODE (t) == ENUMERAL_TYPE && !is_dependent_type) 7396 /* Now that the type has been registered on the instantiations 7397 list, we set up the enumerators. Because the enumeration 7398 constants may involve the enumeration type itself, we make 7399 sure to register the type first, and then create the 7400 constants. That way, doing tsubst_expr for the enumeration 7401 constants won't result in recursive calls here; we'll find 7402 the instantiation and exit above. */ 7403 tsubst_enum (template_type, t, arglist); 7404 7405 if (CLASS_TYPE_P (template_type) && is_dependent_type) 7406 /* If the type makes use of template parameters, the 7407 code that generates debugging information will crash. */ 7408 DECL_IGNORED_P (TYPE_STUB_DECL (t)) = 1; 7409 7410 /* Possibly limit visibility based on template args. */ 7411 TREE_PUBLIC (type_decl) = 1; 7412 determine_visibility (type_decl); 7413 7414 return t; 7415 } 7416 } 7417 7418 /* Wrapper for lookup_template_class_1. */ 7419 7420 tree 7421 lookup_template_class (tree d1, tree arglist, tree in_decl, tree context, 7422 int entering_scope, tsubst_flags_t complain) 7423 { 7424 tree ret; 7425 timevar_push (TV_TEMPLATE_INST); 7426 ret = lookup_template_class_1 (d1, arglist, in_decl, context, 7427 entering_scope, complain); 7428 timevar_pop (TV_TEMPLATE_INST); 7429 return ret; 7430 } 7431 7432 struct pair_fn_data 7433 { 7434 tree_fn_t fn; 7435 void *data; 7436 /* True when we should also visit template parameters that occur in 7437 non-deduced contexts. */ 7438 bool include_nondeduced_p; 7439 struct pointer_set_t *visited; 7440 }; 7441 7442 /* Called from for_each_template_parm via walk_tree. */ 7443 7444 static tree 7445 for_each_template_parm_r (tree *tp, int *walk_subtrees, void *d) 7446 { 7447 tree t = *tp; 7448 struct pair_fn_data *pfd = (struct pair_fn_data *) d; 7449 tree_fn_t fn = pfd->fn; 7450 void *data = pfd->data; 7451 7452 if (TYPE_P (t) 7453 && (pfd->include_nondeduced_p || TREE_CODE (t) != TYPENAME_TYPE) 7454 && for_each_template_parm (TYPE_CONTEXT (t), fn, data, pfd->visited, 7455 pfd->include_nondeduced_p)) 7456 return error_mark_node; 7457 7458 switch (TREE_CODE (t)) 7459 { 7460 case RECORD_TYPE: 7461 if (TYPE_PTRMEMFUNC_P (t)) 7462 break; 7463 /* Fall through. */ 7464 7465 case UNION_TYPE: 7466 case ENUMERAL_TYPE: 7467 if (!TYPE_TEMPLATE_INFO (t)) 7468 *walk_subtrees = 0; 7469 else if (for_each_template_parm (TI_ARGS (TYPE_TEMPLATE_INFO (t)), 7470 fn, data, pfd->visited, 7471 pfd->include_nondeduced_p)) 7472 return error_mark_node; 7473 break; 7474 7475 case INTEGER_TYPE: 7476 if (for_each_template_parm (TYPE_MIN_VALUE (t), 7477 fn, data, pfd->visited, 7478 pfd->include_nondeduced_p) 7479 || for_each_template_parm (TYPE_MAX_VALUE (t), 7480 fn, data, pfd->visited, 7481 pfd->include_nondeduced_p)) 7482 return error_mark_node; 7483 break; 7484 7485 case METHOD_TYPE: 7486 /* Since we're not going to walk subtrees, we have to do this 7487 explicitly here. */ 7488 if (for_each_template_parm (TYPE_METHOD_BASETYPE (t), fn, data, 7489 pfd->visited, pfd->include_nondeduced_p)) 7490 return error_mark_node; 7491 /* Fall through. */ 7492 7493 case FUNCTION_TYPE: 7494 /* Check the return type. */ 7495 if (for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited, 7496 pfd->include_nondeduced_p)) 7497 return error_mark_node; 7498 7499 /* Check the parameter types. Since default arguments are not 7500 instantiated until they are needed, the TYPE_ARG_TYPES may 7501 contain expressions that involve template parameters. But, 7502 no-one should be looking at them yet. And, once they're 7503 instantiated, they don't contain template parameters, so 7504 there's no point in looking at them then, either. */ 7505 { 7506 tree parm; 7507 7508 for (parm = TYPE_ARG_TYPES (t); parm; parm = TREE_CHAIN (parm)) 7509 if (for_each_template_parm (TREE_VALUE (parm), fn, data, 7510 pfd->visited, pfd->include_nondeduced_p)) 7511 return error_mark_node; 7512 7513 /* Since we've already handled the TYPE_ARG_TYPES, we don't 7514 want walk_tree walking into them itself. */ 7515 *walk_subtrees = 0; 7516 } 7517 break; 7518 7519 case TYPEOF_TYPE: 7520 case UNDERLYING_TYPE: 7521 if (pfd->include_nondeduced_p 7522 && for_each_template_parm (TYPE_FIELDS (t), fn, data, 7523 pfd->visited, 7524 pfd->include_nondeduced_p)) 7525 return error_mark_node; 7526 break; 7527 7528 case FUNCTION_DECL: 7529 case VAR_DECL: 7530 if (DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t) 7531 && for_each_template_parm (DECL_TI_ARGS (t), fn, data, 7532 pfd->visited, pfd->include_nondeduced_p)) 7533 return error_mark_node; 7534 /* Fall through. */ 7535 7536 case PARM_DECL: 7537 case CONST_DECL: 7538 if (TREE_CODE (t) == CONST_DECL && DECL_TEMPLATE_PARM_P (t) 7539 && for_each_template_parm (DECL_INITIAL (t), fn, data, 7540 pfd->visited, pfd->include_nondeduced_p)) 7541 return error_mark_node; 7542 if (DECL_CONTEXT (t) 7543 && pfd->include_nondeduced_p 7544 && for_each_template_parm (DECL_CONTEXT (t), fn, data, 7545 pfd->visited, pfd->include_nondeduced_p)) 7546 return error_mark_node; 7547 break; 7548 7549 case BOUND_TEMPLATE_TEMPLATE_PARM: 7550 /* Record template parameters such as `T' inside `TT<T>'. */ 7551 if (for_each_template_parm (TYPE_TI_ARGS (t), fn, data, pfd->visited, 7552 pfd->include_nondeduced_p)) 7553 return error_mark_node; 7554 /* Fall through. */ 7555 7556 case TEMPLATE_TEMPLATE_PARM: 7557 case TEMPLATE_TYPE_PARM: 7558 case TEMPLATE_PARM_INDEX: 7559 if (fn && (*fn)(t, data)) 7560 return error_mark_node; 7561 else if (!fn) 7562 return error_mark_node; 7563 break; 7564 7565 case TEMPLATE_DECL: 7566 /* A template template parameter is encountered. */ 7567 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t) 7568 && for_each_template_parm (TREE_TYPE (t), fn, data, pfd->visited, 7569 pfd->include_nondeduced_p)) 7570 return error_mark_node; 7571 7572 /* Already substituted template template parameter */ 7573 *walk_subtrees = 0; 7574 break; 7575 7576 case TYPENAME_TYPE: 7577 if (!fn 7578 || for_each_template_parm (TYPENAME_TYPE_FULLNAME (t), fn, 7579 data, pfd->visited, 7580 pfd->include_nondeduced_p)) 7581 return error_mark_node; 7582 break; 7583 7584 case CONSTRUCTOR: 7585 if (TREE_TYPE (t) && TYPE_PTRMEMFUNC_P (TREE_TYPE (t)) 7586 && pfd->include_nondeduced_p 7587 && for_each_template_parm (TYPE_PTRMEMFUNC_FN_TYPE 7588 (TREE_TYPE (t)), fn, data, 7589 pfd->visited, pfd->include_nondeduced_p)) 7590 return error_mark_node; 7591 break; 7592 7593 case INDIRECT_REF: 7594 case COMPONENT_REF: 7595 /* If there's no type, then this thing must be some expression 7596 involving template parameters. */ 7597 if (!fn && !TREE_TYPE (t)) 7598 return error_mark_node; 7599 break; 7600 7601 case MODOP_EXPR: 7602 case CAST_EXPR: 7603 case IMPLICIT_CONV_EXPR: 7604 case REINTERPRET_CAST_EXPR: 7605 case CONST_CAST_EXPR: 7606 case STATIC_CAST_EXPR: 7607 case DYNAMIC_CAST_EXPR: 7608 case ARROW_EXPR: 7609 case DOTSTAR_EXPR: 7610 case TYPEID_EXPR: 7611 case PSEUDO_DTOR_EXPR: 7612 if (!fn) 7613 return error_mark_node; 7614 break; 7615 7616 default: 7617 break; 7618 } 7619 7620 /* We didn't find any template parameters we liked. */ 7621 return NULL_TREE; 7622 } 7623 7624 /* For each TEMPLATE_TYPE_PARM, TEMPLATE_TEMPLATE_PARM, 7625 BOUND_TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX in T, 7626 call FN with the parameter and the DATA. 7627 If FN returns nonzero, the iteration is terminated, and 7628 for_each_template_parm returns 1. Otherwise, the iteration 7629 continues. If FN never returns a nonzero value, the value 7630 returned by for_each_template_parm is 0. If FN is NULL, it is 7631 considered to be the function which always returns 1. 7632 7633 If INCLUDE_NONDEDUCED_P, then this routine will also visit template 7634 parameters that occur in non-deduced contexts. When false, only 7635 visits those template parameters that can be deduced. */ 7636 7637 static int 7638 for_each_template_parm (tree t, tree_fn_t fn, void* data, 7639 struct pointer_set_t *visited, 7640 bool include_nondeduced_p) 7641 { 7642 struct pair_fn_data pfd; 7643 int result; 7644 7645 /* Set up. */ 7646 pfd.fn = fn; 7647 pfd.data = data; 7648 pfd.include_nondeduced_p = include_nondeduced_p; 7649 7650 /* Walk the tree. (Conceptually, we would like to walk without 7651 duplicates, but for_each_template_parm_r recursively calls 7652 for_each_template_parm, so we would need to reorganize a fair 7653 bit to use walk_tree_without_duplicates, so we keep our own 7654 visited list.) */ 7655 if (visited) 7656 pfd.visited = visited; 7657 else 7658 pfd.visited = pointer_set_create (); 7659 result = cp_walk_tree (&t, 7660 for_each_template_parm_r, 7661 &pfd, 7662 pfd.visited) != NULL_TREE; 7663 7664 /* Clean up. */ 7665 if (!visited) 7666 { 7667 pointer_set_destroy (pfd.visited); 7668 pfd.visited = 0; 7669 } 7670 7671 return result; 7672 } 7673 7674 /* Returns true if T depends on any template parameter. */ 7675 7676 int 7677 uses_template_parms (tree t) 7678 { 7679 bool dependent_p; 7680 int saved_processing_template_decl; 7681 7682 saved_processing_template_decl = processing_template_decl; 7683 if (!saved_processing_template_decl) 7684 processing_template_decl = 1; 7685 if (TYPE_P (t)) 7686 dependent_p = dependent_type_p (t); 7687 else if (TREE_CODE (t) == TREE_VEC) 7688 dependent_p = any_dependent_template_arguments_p (t); 7689 else if (TREE_CODE (t) == TREE_LIST) 7690 dependent_p = (uses_template_parms (TREE_VALUE (t)) 7691 || uses_template_parms (TREE_CHAIN (t))); 7692 else if (TREE_CODE (t) == TYPE_DECL) 7693 dependent_p = dependent_type_p (TREE_TYPE (t)); 7694 else if (DECL_P (t) 7695 || EXPR_P (t) 7696 || TREE_CODE (t) == TEMPLATE_PARM_INDEX 7697 || TREE_CODE (t) == OVERLOAD 7698 || BASELINK_P (t) 7699 || TREE_CODE (t) == IDENTIFIER_NODE 7700 || TREE_CODE (t) == TRAIT_EXPR 7701 || TREE_CODE (t) == CONSTRUCTOR 7702 || CONSTANT_CLASS_P (t)) 7703 dependent_p = (type_dependent_expression_p (t) 7704 || value_dependent_expression_p (t)); 7705 else 7706 { 7707 gcc_assert (t == error_mark_node); 7708 dependent_p = false; 7709 } 7710 7711 processing_template_decl = saved_processing_template_decl; 7712 7713 return dependent_p; 7714 } 7715 7716 /* Returns true if T depends on any template parameter with level LEVEL. */ 7717 7718 int 7719 uses_template_parms_level (tree t, int level) 7720 { 7721 return for_each_template_parm (t, template_parm_this_level_p, &level, NULL, 7722 /*include_nondeduced_p=*/true); 7723 } 7724 7725 /* Returns TRUE iff INST is an instantiation we don't need to do in an 7726 ill-formed translation unit, i.e. a variable or function that isn't 7727 usable in a constant expression. */ 7728 7729 static inline bool 7730 neglectable_inst_p (tree d) 7731 { 7732 return (DECL_P (d) 7733 && !(TREE_CODE (d) == FUNCTION_DECL ? DECL_DECLARED_CONSTEXPR_P (d) 7734 : decl_maybe_constant_var_p (d))); 7735 } 7736 7737 /* Returns TRUE iff we should refuse to instantiate DECL because it's 7738 neglectable and instantiated from within an erroneous instantiation. */ 7739 7740 static bool 7741 limit_bad_template_recursion (tree decl) 7742 { 7743 struct tinst_level *lev = current_tinst_level; 7744 int errs = errorcount + sorrycount; 7745 if (lev == NULL || errs == 0 || !neglectable_inst_p (decl)) 7746 return false; 7747 7748 for (; lev; lev = lev->next) 7749 if (neglectable_inst_p (lev->decl)) 7750 break; 7751 7752 return (lev && errs > lev->errors); 7753 } 7754 7755 static int tinst_depth; 7756 extern int max_tinst_depth; 7757 #ifdef GATHER_STATISTICS 7758 int depth_reached; 7759 #endif 7760 static GTY(()) struct tinst_level *last_error_tinst_level; 7761 7762 /* We're starting to instantiate D; record the template instantiation context 7763 for diagnostics and to restore it later. */ 7764 7765 int 7766 push_tinst_level (tree d) 7767 { 7768 struct tinst_level *new_level; 7769 7770 if (tinst_depth >= max_tinst_depth) 7771 { 7772 last_error_tinst_level = current_tinst_level; 7773 if (TREE_CODE (d) == TREE_LIST) 7774 error ("template instantiation depth exceeds maximum of %d (use " 7775 "-ftemplate-depth= to increase the maximum) substituting %qS", 7776 max_tinst_depth, d); 7777 else 7778 error ("template instantiation depth exceeds maximum of %d (use " 7779 "-ftemplate-depth= to increase the maximum) instantiating %qD", 7780 max_tinst_depth, d); 7781 7782 print_instantiation_context (); 7783 7784 return 0; 7785 } 7786 7787 /* If the current instantiation caused problems, don't let it instantiate 7788 anything else. Do allow deduction substitution and decls usable in 7789 constant expressions. */ 7790 if (limit_bad_template_recursion (d)) 7791 return 0; 7792 7793 new_level = ggc_alloc_tinst_level (); 7794 new_level->decl = d; 7795 new_level->locus = input_location; 7796 new_level->errors = errorcount+sorrycount; 7797 new_level->in_system_header_p = in_system_header; 7798 new_level->next = current_tinst_level; 7799 current_tinst_level = new_level; 7800 7801 ++tinst_depth; 7802 #ifdef GATHER_STATISTICS 7803 if (tinst_depth > depth_reached) 7804 depth_reached = tinst_depth; 7805 #endif 7806 7807 return 1; 7808 } 7809 7810 /* We're done instantiating this template; return to the instantiation 7811 context. */ 7812 7813 void 7814 pop_tinst_level (void) 7815 { 7816 /* Restore the filename and line number stashed away when we started 7817 this instantiation. */ 7818 input_location = current_tinst_level->locus; 7819 current_tinst_level = current_tinst_level->next; 7820 --tinst_depth; 7821 } 7822 7823 /* We're instantiating a deferred template; restore the template 7824 instantiation context in which the instantiation was requested, which 7825 is one step out from LEVEL. Return the corresponding DECL or TYPE. */ 7826 7827 static tree 7828 reopen_tinst_level (struct tinst_level *level) 7829 { 7830 struct tinst_level *t; 7831 7832 tinst_depth = 0; 7833 for (t = level; t; t = t->next) 7834 ++tinst_depth; 7835 7836 current_tinst_level = level; 7837 pop_tinst_level (); 7838 if (current_tinst_level) 7839 current_tinst_level->errors = errorcount+sorrycount; 7840 return level->decl; 7841 } 7842 7843 /* Returns the TINST_LEVEL which gives the original instantiation 7844 context. */ 7845 7846 struct tinst_level * 7847 outermost_tinst_level (void) 7848 { 7849 struct tinst_level *level = current_tinst_level; 7850 if (level) 7851 while (level->next) 7852 level = level->next; 7853 return level; 7854 } 7855 7856 /* Returns TRUE if PARM is a parameter of the template TEMPL. */ 7857 7858 bool 7859 parameter_of_template_p (tree parm, tree templ) 7860 { 7861 tree parms; 7862 int i; 7863 7864 if (!parm || !templ) 7865 return false; 7866 7867 gcc_assert (DECL_TEMPLATE_PARM_P (parm)); 7868 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL); 7869 7870 parms = DECL_TEMPLATE_PARMS (templ); 7871 parms = INNERMOST_TEMPLATE_PARMS (parms); 7872 7873 for (i = 0; i < TREE_VEC_LENGTH (parms); ++i) 7874 { 7875 tree p = TREE_VALUE (TREE_VEC_ELT (parms, i)); 7876 if (p == error_mark_node) 7877 continue; 7878 7879 if (parm == p 7880 || (DECL_INITIAL (parm) 7881 && DECL_INITIAL (parm) == DECL_INITIAL (p))) 7882 return true; 7883 } 7884 7885 return false; 7886 } 7887 7888 /* DECL is a friend FUNCTION_DECL or TEMPLATE_DECL. ARGS is the 7889 vector of template arguments, as for tsubst. 7890 7891 Returns an appropriate tsubst'd friend declaration. */ 7892 7893 static tree 7894 tsubst_friend_function (tree decl, tree args) 7895 { 7896 tree new_friend; 7897 7898 if (TREE_CODE (decl) == FUNCTION_DECL 7899 && DECL_TEMPLATE_INSTANTIATION (decl) 7900 && TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL) 7901 /* This was a friend declared with an explicit template 7902 argument list, e.g.: 7903 7904 friend void f<>(T); 7905 7906 to indicate that f was a template instantiation, not a new 7907 function declaration. Now, we have to figure out what 7908 instantiation of what template. */ 7909 { 7910 tree template_id, arglist, fns; 7911 tree new_args; 7912 tree tmpl; 7913 tree ns = decl_namespace_context (TYPE_MAIN_DECL (current_class_type)); 7914 7915 /* Friend functions are looked up in the containing namespace scope. 7916 We must enter that scope, to avoid finding member functions of the 7917 current class with same name. */ 7918 push_nested_namespace (ns); 7919 fns = tsubst_expr (DECL_TI_TEMPLATE (decl), args, 7920 tf_warning_or_error, NULL_TREE, 7921 /*integral_constant_expression_p=*/false); 7922 pop_nested_namespace (ns); 7923 arglist = tsubst (DECL_TI_ARGS (decl), args, 7924 tf_warning_or_error, NULL_TREE); 7925 template_id = lookup_template_function (fns, arglist); 7926 7927 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE); 7928 tmpl = determine_specialization (template_id, new_friend, 7929 &new_args, 7930 /*need_member_template=*/0, 7931 TREE_VEC_LENGTH (args), 7932 tsk_none); 7933 return instantiate_template (tmpl, new_args, tf_error); 7934 } 7935 7936 new_friend = tsubst (decl, args, tf_warning_or_error, NULL_TREE); 7937 7938 /* The NEW_FRIEND will look like an instantiation, to the 7939 compiler, but is not an instantiation from the point of view of 7940 the language. For example, we might have had: 7941 7942 template <class T> struct S { 7943 template <class U> friend void f(T, U); 7944 }; 7945 7946 Then, in S<int>, template <class U> void f(int, U) is not an 7947 instantiation of anything. */ 7948 if (new_friend == error_mark_node) 7949 return error_mark_node; 7950 7951 DECL_USE_TEMPLATE (new_friend) = 0; 7952 if (TREE_CODE (decl) == TEMPLATE_DECL) 7953 { 7954 DECL_USE_TEMPLATE (DECL_TEMPLATE_RESULT (new_friend)) = 0; 7955 DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (new_friend)) 7956 = DECL_SAVED_TREE (DECL_TEMPLATE_RESULT (decl)); 7957 } 7958 7959 /* The mangled name for the NEW_FRIEND is incorrect. The function 7960 is not a template instantiation and should not be mangled like 7961 one. Therefore, we forget the mangling here; we'll recompute it 7962 later if we need it. */ 7963 if (TREE_CODE (new_friend) != TEMPLATE_DECL) 7964 { 7965 SET_DECL_RTL (new_friend, NULL); 7966 SET_DECL_ASSEMBLER_NAME (new_friend, NULL_TREE); 7967 } 7968 7969 if (DECL_NAMESPACE_SCOPE_P (new_friend)) 7970 { 7971 tree old_decl; 7972 tree new_friend_template_info; 7973 tree new_friend_result_template_info; 7974 tree ns; 7975 int new_friend_is_defn; 7976 7977 /* We must save some information from NEW_FRIEND before calling 7978 duplicate decls since that function will free NEW_FRIEND if 7979 possible. */ 7980 new_friend_template_info = DECL_TEMPLATE_INFO (new_friend); 7981 new_friend_is_defn = 7982 (DECL_INITIAL (DECL_TEMPLATE_RESULT 7983 (template_for_substitution (new_friend))) 7984 != NULL_TREE); 7985 if (TREE_CODE (new_friend) == TEMPLATE_DECL) 7986 { 7987 /* This declaration is a `primary' template. */ 7988 DECL_PRIMARY_TEMPLATE (new_friend) = new_friend; 7989 7990 new_friend_result_template_info 7991 = DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (new_friend)); 7992 } 7993 else 7994 new_friend_result_template_info = NULL_TREE; 7995 7996 /* Make the init_value nonzero so pushdecl knows this is a defn. */ 7997 if (new_friend_is_defn) 7998 DECL_INITIAL (new_friend) = error_mark_node; 7999 8000 /* Inside pushdecl_namespace_level, we will push into the 8001 current namespace. However, the friend function should go 8002 into the namespace of the template. */ 8003 ns = decl_namespace_context (new_friend); 8004 push_nested_namespace (ns); 8005 old_decl = pushdecl_namespace_level (new_friend, /*is_friend=*/true); 8006 pop_nested_namespace (ns); 8007 8008 if (old_decl == error_mark_node) 8009 return error_mark_node; 8010 8011 if (old_decl != new_friend) 8012 { 8013 /* This new friend declaration matched an existing 8014 declaration. For example, given: 8015 8016 template <class T> void f(T); 8017 template <class U> class C { 8018 template <class T> friend void f(T) {} 8019 }; 8020 8021 the friend declaration actually provides the definition 8022 of `f', once C has been instantiated for some type. So, 8023 old_decl will be the out-of-class template declaration, 8024 while new_friend is the in-class definition. 8025 8026 But, if `f' was called before this point, the 8027 instantiation of `f' will have DECL_TI_ARGS corresponding 8028 to `T' but not to `U', references to which might appear 8029 in the definition of `f'. Previously, the most general 8030 template for an instantiation of `f' was the out-of-class 8031 version; now it is the in-class version. Therefore, we 8032 run through all specialization of `f', adding to their 8033 DECL_TI_ARGS appropriately. In particular, they need a 8034 new set of outer arguments, corresponding to the 8035 arguments for this class instantiation. 8036 8037 The same situation can arise with something like this: 8038 8039 friend void f(int); 8040 template <class T> class C { 8041 friend void f(T) {} 8042 }; 8043 8044 when `C<int>' is instantiated. Now, `f(int)' is defined 8045 in the class. */ 8046 8047 if (!new_friend_is_defn) 8048 /* On the other hand, if the in-class declaration does 8049 *not* provide a definition, then we don't want to alter 8050 existing definitions. We can just leave everything 8051 alone. */ 8052 ; 8053 else 8054 { 8055 tree new_template = TI_TEMPLATE (new_friend_template_info); 8056 tree new_args = TI_ARGS (new_friend_template_info); 8057 8058 /* Overwrite whatever template info was there before, if 8059 any, with the new template information pertaining to 8060 the declaration. */ 8061 DECL_TEMPLATE_INFO (old_decl) = new_friend_template_info; 8062 8063 if (TREE_CODE (old_decl) != TEMPLATE_DECL) 8064 { 8065 /* We should have called reregister_specialization in 8066 duplicate_decls. */ 8067 gcc_assert (retrieve_specialization (new_template, 8068 new_args, 0) 8069 == old_decl); 8070 8071 /* Instantiate it if the global has already been used. */ 8072 if (DECL_ODR_USED (old_decl)) 8073 instantiate_decl (old_decl, /*defer_ok=*/true, 8074 /*expl_inst_class_mem_p=*/false); 8075 } 8076 else 8077 { 8078 tree t; 8079 8080 /* Indicate that the old function template is a partial 8081 instantiation. */ 8082 DECL_TEMPLATE_INFO (DECL_TEMPLATE_RESULT (old_decl)) 8083 = new_friend_result_template_info; 8084 8085 gcc_assert (new_template 8086 == most_general_template (new_template)); 8087 gcc_assert (new_template != old_decl); 8088 8089 /* Reassign any specializations already in the hash table 8090 to the new more general template, and add the 8091 additional template args. */ 8092 for (t = DECL_TEMPLATE_INSTANTIATIONS (old_decl); 8093 t != NULL_TREE; 8094 t = TREE_CHAIN (t)) 8095 { 8096 tree spec = TREE_VALUE (t); 8097 spec_entry elt; 8098 8099 elt.tmpl = old_decl; 8100 elt.args = DECL_TI_ARGS (spec); 8101 elt.spec = NULL_TREE; 8102 8103 htab_remove_elt (decl_specializations, &elt); 8104 8105 DECL_TI_ARGS (spec) 8106 = add_outermost_template_args (new_args, 8107 DECL_TI_ARGS (spec)); 8108 8109 register_specialization 8110 (spec, new_template, DECL_TI_ARGS (spec), true, 0); 8111 8112 } 8113 DECL_TEMPLATE_INSTANTIATIONS (old_decl) = NULL_TREE; 8114 } 8115 } 8116 8117 /* The information from NEW_FRIEND has been merged into OLD_DECL 8118 by duplicate_decls. */ 8119 new_friend = old_decl; 8120 } 8121 } 8122 else 8123 { 8124 tree context = DECL_CONTEXT (new_friend); 8125 bool dependent_p; 8126 8127 /* In the code 8128 template <class T> class C { 8129 template <class U> friend void C1<U>::f (); // case 1 8130 friend void C2<T>::f (); // case 2 8131 }; 8132 we only need to make sure CONTEXT is a complete type for 8133 case 2. To distinguish between the two cases, we note that 8134 CONTEXT of case 1 remains dependent type after tsubst while 8135 this isn't true for case 2. */ 8136 ++processing_template_decl; 8137 dependent_p = dependent_type_p (context); 8138 --processing_template_decl; 8139 8140 if (!dependent_p 8141 && !complete_type_or_else (context, NULL_TREE)) 8142 return error_mark_node; 8143 8144 if (COMPLETE_TYPE_P (context)) 8145 { 8146 /* Check to see that the declaration is really present, and, 8147 possibly obtain an improved declaration. */ 8148 tree fn = check_classfn (context, 8149 new_friend, NULL_TREE); 8150 8151 if (fn) 8152 new_friend = fn; 8153 } 8154 } 8155 8156 return new_friend; 8157 } 8158 8159 /* FRIEND_TMPL is a friend TEMPLATE_DECL. ARGS is the vector of 8160 template arguments, as for tsubst. 8161 8162 Returns an appropriate tsubst'd friend type or error_mark_node on 8163 failure. */ 8164 8165 static tree 8166 tsubst_friend_class (tree friend_tmpl, tree args) 8167 { 8168 tree friend_type; 8169 tree tmpl; 8170 tree context; 8171 8172 context = CP_DECL_CONTEXT (friend_tmpl); 8173 8174 if (context != global_namespace) 8175 { 8176 if (TREE_CODE (context) == NAMESPACE_DECL) 8177 push_nested_namespace (context); 8178 else 8179 push_nested_class (tsubst (context, args, tf_none, NULL_TREE)); 8180 } 8181 8182 /* Look for a class template declaration. We look for hidden names 8183 because two friend declarations of the same template are the 8184 same. For example, in: 8185 8186 struct A { 8187 template <typename> friend class F; 8188 }; 8189 template <typename> struct B { 8190 template <typename> friend class F; 8191 }; 8192 8193 both F templates are the same. */ 8194 tmpl = lookup_name_real (DECL_NAME (friend_tmpl), 0, 0, 8195 /*block_p=*/true, 0, 8196 LOOKUP_COMPLAIN | LOOKUP_HIDDEN); 8197 8198 /* But, if we don't find one, it might be because we're in a 8199 situation like this: 8200 8201 template <class T> 8202 struct S { 8203 template <class U> 8204 friend struct S; 8205 }; 8206 8207 Here, in the scope of (say) S<int>, `S' is bound to a TYPE_DECL 8208 for `S<int>', not the TEMPLATE_DECL. */ 8209 if (!tmpl || !DECL_CLASS_TEMPLATE_P (tmpl)) 8210 { 8211 tmpl = lookup_name_prefer_type (DECL_NAME (friend_tmpl), 1); 8212 tmpl = maybe_get_template_decl_from_type_decl (tmpl); 8213 } 8214 8215 if (tmpl && DECL_CLASS_TEMPLATE_P (tmpl)) 8216 { 8217 /* The friend template has already been declared. Just 8218 check to see that the declarations match, and install any new 8219 default parameters. We must tsubst the default parameters, 8220 of course. We only need the innermost template parameters 8221 because that is all that redeclare_class_template will look 8222 at. */ 8223 if (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (friend_tmpl)) 8224 > TMPL_ARGS_DEPTH (args)) 8225 { 8226 tree parms; 8227 location_t saved_input_location; 8228 parms = tsubst_template_parms (DECL_TEMPLATE_PARMS (friend_tmpl), 8229 args, tf_warning_or_error); 8230 8231 saved_input_location = input_location; 8232 input_location = DECL_SOURCE_LOCATION (friend_tmpl); 8233 redeclare_class_template (TREE_TYPE (tmpl), parms); 8234 input_location = saved_input_location; 8235 8236 } 8237 8238 friend_type = TREE_TYPE (tmpl); 8239 } 8240 else 8241 { 8242 /* The friend template has not already been declared. In this 8243 case, the instantiation of the template class will cause the 8244 injection of this template into the global scope. */ 8245 tmpl = tsubst (friend_tmpl, args, tf_warning_or_error, NULL_TREE); 8246 if (tmpl == error_mark_node) 8247 return error_mark_node; 8248 8249 /* The new TMPL is not an instantiation of anything, so we 8250 forget its origins. We don't reset CLASSTYPE_TI_TEMPLATE for 8251 the new type because that is supposed to be the corresponding 8252 template decl, i.e., TMPL. */ 8253 DECL_USE_TEMPLATE (tmpl) = 0; 8254 DECL_TEMPLATE_INFO (tmpl) = NULL_TREE; 8255 CLASSTYPE_USE_TEMPLATE (TREE_TYPE (tmpl)) = 0; 8256 CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl)) 8257 = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (TREE_TYPE (tmpl))); 8258 8259 /* Inject this template into the global scope. */ 8260 friend_type = TREE_TYPE (pushdecl_top_level_maybe_friend (tmpl, true)); 8261 } 8262 8263 if (context != global_namespace) 8264 { 8265 if (TREE_CODE (context) == NAMESPACE_DECL) 8266 pop_nested_namespace (context); 8267 else 8268 pop_nested_class (); 8269 } 8270 8271 return friend_type; 8272 } 8273 8274 /* Returns zero if TYPE cannot be completed later due to circularity. 8275 Otherwise returns one. */ 8276 8277 static int 8278 can_complete_type_without_circularity (tree type) 8279 { 8280 if (type == NULL_TREE || type == error_mark_node) 8281 return 0; 8282 else if (COMPLETE_TYPE_P (type)) 8283 return 1; 8284 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type)) 8285 return can_complete_type_without_circularity (TREE_TYPE (type)); 8286 else if (CLASS_TYPE_P (type) 8287 && TYPE_BEING_DEFINED (TYPE_MAIN_VARIANT (type))) 8288 return 0; 8289 else 8290 return 1; 8291 } 8292 8293 /* Apply any attributes which had to be deferred until instantiation 8294 time. DECL_P, ATTRIBUTES and ATTR_FLAGS are as cplus_decl_attributes; 8295 ARGS, COMPLAIN, IN_DECL are as tsubst. */ 8296 8297 static void 8298 apply_late_template_attributes (tree *decl_p, tree attributes, int attr_flags, 8299 tree args, tsubst_flags_t complain, tree in_decl) 8300 { 8301 tree last_dep = NULL_TREE; 8302 tree t; 8303 tree *p; 8304 8305 for (t = attributes; t; t = TREE_CHAIN (t)) 8306 if (ATTR_IS_DEPENDENT (t)) 8307 { 8308 last_dep = t; 8309 attributes = copy_list (attributes); 8310 break; 8311 } 8312 8313 if (DECL_P (*decl_p)) 8314 { 8315 if (TREE_TYPE (*decl_p) == error_mark_node) 8316 return; 8317 p = &DECL_ATTRIBUTES (*decl_p); 8318 } 8319 else 8320 p = &TYPE_ATTRIBUTES (*decl_p); 8321 8322 if (last_dep) 8323 { 8324 tree late_attrs = NULL_TREE; 8325 tree *q = &late_attrs; 8326 8327 for (*p = attributes; *p; ) 8328 { 8329 t = *p; 8330 if (ATTR_IS_DEPENDENT (t)) 8331 { 8332 *p = TREE_CHAIN (t); 8333 TREE_CHAIN (t) = NULL_TREE; 8334 /* If the first attribute argument is an identifier, don't 8335 pass it through tsubst. Attributes like mode, format, 8336 cleanup and several target specific attributes expect it 8337 unmodified. */ 8338 if (TREE_VALUE (t) 8339 && TREE_CODE (TREE_VALUE (t)) == TREE_LIST 8340 && TREE_VALUE (TREE_VALUE (t)) 8341 && (TREE_CODE (TREE_VALUE (TREE_VALUE (t))) 8342 == IDENTIFIER_NODE)) 8343 { 8344 tree chain 8345 = tsubst_expr (TREE_CHAIN (TREE_VALUE (t)), args, complain, 8346 in_decl, 8347 /*integral_constant_expression_p=*/false); 8348 if (chain != TREE_CHAIN (TREE_VALUE (t))) 8349 TREE_VALUE (t) 8350 = tree_cons (NULL_TREE, TREE_VALUE (TREE_VALUE (t)), 8351 chain); 8352 } 8353 else 8354 TREE_VALUE (t) 8355 = tsubst_expr (TREE_VALUE (t), args, complain, in_decl, 8356 /*integral_constant_expression_p=*/false); 8357 *q = t; 8358 q = &TREE_CHAIN (t); 8359 } 8360 else 8361 p = &TREE_CHAIN (t); 8362 } 8363 8364 cplus_decl_attributes (decl_p, late_attrs, attr_flags); 8365 } 8366 } 8367 8368 /* Perform (or defer) access check for typedefs that were referenced 8369 from within the template TMPL code. 8370 This is a subroutine of instantiate_template and instantiate_class_template. 8371 TMPL is the template to consider and TARGS is the list of arguments of 8372 that template. */ 8373 8374 static void 8375 perform_typedefs_access_check (tree tmpl, tree targs) 8376 { 8377 location_t saved_location; 8378 int i; 8379 qualified_typedef_usage_t *iter; 8380 8381 if (!tmpl 8382 || (!CLASS_TYPE_P (tmpl) 8383 && TREE_CODE (tmpl) != FUNCTION_DECL)) 8384 return; 8385 8386 saved_location = input_location; 8387 FOR_EACH_VEC_ELT (qualified_typedef_usage_t, 8388 get_types_needing_access_check (tmpl), 8389 i, iter) 8390 { 8391 tree type_decl = iter->typedef_decl; 8392 tree type_scope = iter->context; 8393 8394 if (!type_decl || !type_scope || !CLASS_TYPE_P (type_scope)) 8395 continue; 8396 8397 if (uses_template_parms (type_decl)) 8398 type_decl = tsubst (type_decl, targs, tf_error, NULL_TREE); 8399 if (uses_template_parms (type_scope)) 8400 type_scope = tsubst (type_scope, targs, tf_error, NULL_TREE); 8401 8402 /* Make access check error messages point to the location 8403 of the use of the typedef. */ 8404 input_location = iter->locus; 8405 perform_or_defer_access_check (TYPE_BINFO (type_scope), 8406 type_decl, type_decl); 8407 } 8408 input_location = saved_location; 8409 } 8410 8411 static tree 8412 instantiate_class_template_1 (tree type) 8413 { 8414 tree templ, args, pattern, t, member; 8415 tree typedecl; 8416 tree pbinfo; 8417 tree base_list; 8418 unsigned int saved_maximum_field_alignment; 8419 tree fn_context; 8420 8421 if (type == error_mark_node) 8422 return error_mark_node; 8423 8424 if (COMPLETE_OR_OPEN_TYPE_P (type) 8425 || uses_template_parms (type)) 8426 return type; 8427 8428 /* Figure out which template is being instantiated. */ 8429 templ = most_general_template (CLASSTYPE_TI_TEMPLATE (type)); 8430 gcc_assert (TREE_CODE (templ) == TEMPLATE_DECL); 8431 8432 /* Determine what specialization of the original template to 8433 instantiate. */ 8434 t = most_specialized_class (type, templ, tf_warning_or_error); 8435 if (t == error_mark_node) 8436 { 8437 TYPE_BEING_DEFINED (type) = 1; 8438 return error_mark_node; 8439 } 8440 else if (t) 8441 { 8442 /* This TYPE is actually an instantiation of a partial 8443 specialization. We replace the innermost set of ARGS with 8444 the arguments appropriate for substitution. For example, 8445 given: 8446 8447 template <class T> struct S {}; 8448 template <class T> struct S<T*> {}; 8449 8450 and supposing that we are instantiating S<int*>, ARGS will 8451 presently be {int*} -- but we need {int}. */ 8452 pattern = TREE_TYPE (t); 8453 args = TREE_PURPOSE (t); 8454 } 8455 else 8456 { 8457 pattern = TREE_TYPE (templ); 8458 args = CLASSTYPE_TI_ARGS (type); 8459 } 8460 8461 /* If the template we're instantiating is incomplete, then clearly 8462 there's nothing we can do. */ 8463 if (!COMPLETE_TYPE_P (pattern)) 8464 return type; 8465 8466 /* If we've recursively instantiated too many templates, stop. */ 8467 if (! push_tinst_level (type)) 8468 return type; 8469 8470 /* Now we're really doing the instantiation. Mark the type as in 8471 the process of being defined. */ 8472 TYPE_BEING_DEFINED (type) = 1; 8473 8474 /* We may be in the middle of deferred access check. Disable 8475 it now. */ 8476 push_deferring_access_checks (dk_no_deferred); 8477 8478 fn_context = decl_function_context (TYPE_MAIN_DECL (type)); 8479 if (!fn_context) 8480 push_to_top_level (); 8481 /* Use #pragma pack from the template context. */ 8482 saved_maximum_field_alignment = maximum_field_alignment; 8483 maximum_field_alignment = TYPE_PRECISION (pattern); 8484 8485 SET_CLASSTYPE_INTERFACE_UNKNOWN (type); 8486 8487 /* Set the input location to the most specialized template definition. 8488 This is needed if tsubsting causes an error. */ 8489 typedecl = TYPE_MAIN_DECL (pattern); 8490 input_location = DECL_SOURCE_LOCATION (TYPE_NAME (type)) = 8491 DECL_SOURCE_LOCATION (typedecl); 8492 8493 TYPE_PACKED (type) = TYPE_PACKED (pattern); 8494 TYPE_ALIGN (type) = TYPE_ALIGN (pattern); 8495 TYPE_USER_ALIGN (type) = TYPE_USER_ALIGN (pattern); 8496 TYPE_FOR_JAVA (type) = TYPE_FOR_JAVA (pattern); /* For libjava's JArray<T> */ 8497 if (ANON_AGGR_TYPE_P (pattern)) 8498 SET_ANON_AGGR_TYPE_P (type); 8499 if (CLASSTYPE_VISIBILITY_SPECIFIED (pattern)) 8500 { 8501 CLASSTYPE_VISIBILITY_SPECIFIED (type) = 1; 8502 CLASSTYPE_VISIBILITY (type) = CLASSTYPE_VISIBILITY (pattern); 8503 /* Adjust visibility for template arguments. */ 8504 determine_visibility (TYPE_MAIN_DECL (type)); 8505 } 8506 CLASSTYPE_FINAL (type) = CLASSTYPE_FINAL (pattern); 8507 8508 pbinfo = TYPE_BINFO (pattern); 8509 8510 /* We should never instantiate a nested class before its enclosing 8511 class; we need to look up the nested class by name before we can 8512 instantiate it, and that lookup should instantiate the enclosing 8513 class. */ 8514 gcc_assert (!DECL_CLASS_SCOPE_P (TYPE_MAIN_DECL (pattern)) 8515 || COMPLETE_OR_OPEN_TYPE_P (TYPE_CONTEXT (type))); 8516 8517 base_list = NULL_TREE; 8518 if (BINFO_N_BASE_BINFOS (pbinfo)) 8519 { 8520 tree pbase_binfo; 8521 tree pushed_scope; 8522 int i; 8523 8524 /* We must enter the scope containing the type, as that is where 8525 the accessibility of types named in dependent bases are 8526 looked up from. */ 8527 pushed_scope = push_scope (CP_TYPE_CONTEXT (type)); 8528 8529 /* Substitute into each of the bases to determine the actual 8530 basetypes. */ 8531 for (i = 0; BINFO_BASE_ITERATE (pbinfo, i, pbase_binfo); i++) 8532 { 8533 tree base; 8534 tree access = BINFO_BASE_ACCESS (pbinfo, i); 8535 tree expanded_bases = NULL_TREE; 8536 int idx, len = 1; 8537 8538 if (PACK_EXPANSION_P (BINFO_TYPE (pbase_binfo))) 8539 { 8540 expanded_bases = 8541 tsubst_pack_expansion (BINFO_TYPE (pbase_binfo), 8542 args, tf_error, NULL_TREE); 8543 if (expanded_bases == error_mark_node) 8544 continue; 8545 8546 len = TREE_VEC_LENGTH (expanded_bases); 8547 } 8548 8549 for (idx = 0; idx < len; idx++) 8550 { 8551 if (expanded_bases) 8552 /* Extract the already-expanded base class. */ 8553 base = TREE_VEC_ELT (expanded_bases, idx); 8554 else 8555 /* Substitute to figure out the base class. */ 8556 base = tsubst (BINFO_TYPE (pbase_binfo), args, tf_error, 8557 NULL_TREE); 8558 8559 if (base == error_mark_node) 8560 continue; 8561 8562 base_list = tree_cons (access, base, base_list); 8563 if (BINFO_VIRTUAL_P (pbase_binfo)) 8564 TREE_TYPE (base_list) = integer_type_node; 8565 } 8566 } 8567 8568 /* The list is now in reverse order; correct that. */ 8569 base_list = nreverse (base_list); 8570 8571 if (pushed_scope) 8572 pop_scope (pushed_scope); 8573 } 8574 /* Now call xref_basetypes to set up all the base-class 8575 information. */ 8576 xref_basetypes (type, base_list); 8577 8578 apply_late_template_attributes (&type, TYPE_ATTRIBUTES (pattern), 8579 (int) ATTR_FLAG_TYPE_IN_PLACE, 8580 args, tf_error, NULL_TREE); 8581 fixup_attribute_variants (type); 8582 8583 /* Now that our base classes are set up, enter the scope of the 8584 class, so that name lookups into base classes, etc. will work 8585 correctly. This is precisely analogous to what we do in 8586 begin_class_definition when defining an ordinary non-template 8587 class, except we also need to push the enclosing classes. */ 8588 push_nested_class (type); 8589 8590 /* Now members are processed in the order of declaration. */ 8591 for (member = CLASSTYPE_DECL_LIST (pattern); 8592 member; member = TREE_CHAIN (member)) 8593 { 8594 tree t = TREE_VALUE (member); 8595 8596 if (TREE_PURPOSE (member)) 8597 { 8598 if (TYPE_P (t)) 8599 { 8600 /* Build new CLASSTYPE_NESTED_UTDS. */ 8601 8602 tree newtag; 8603 bool class_template_p; 8604 8605 class_template_p = (TREE_CODE (t) != ENUMERAL_TYPE 8606 && TYPE_LANG_SPECIFIC (t) 8607 && CLASSTYPE_IS_TEMPLATE (t)); 8608 /* If the member is a class template, then -- even after 8609 substitution -- there may be dependent types in the 8610 template argument list for the class. We increment 8611 PROCESSING_TEMPLATE_DECL so that dependent_type_p, as 8612 that function will assume that no types are dependent 8613 when outside of a template. */ 8614 if (class_template_p) 8615 ++processing_template_decl; 8616 newtag = tsubst (t, args, tf_error, NULL_TREE); 8617 if (class_template_p) 8618 --processing_template_decl; 8619 if (newtag == error_mark_node) 8620 continue; 8621 8622 if (TREE_CODE (newtag) != ENUMERAL_TYPE) 8623 { 8624 tree name = TYPE_IDENTIFIER (t); 8625 8626 if (class_template_p) 8627 /* Unfortunately, lookup_template_class sets 8628 CLASSTYPE_IMPLICIT_INSTANTIATION for a partial 8629 instantiation (i.e., for the type of a member 8630 template class nested within a template class.) 8631 This behavior is required for 8632 maybe_process_partial_specialization to work 8633 correctly, but is not accurate in this case; 8634 the TAG is not an instantiation of anything. 8635 (The corresponding TEMPLATE_DECL is an 8636 instantiation, but the TYPE is not.) */ 8637 CLASSTYPE_USE_TEMPLATE (newtag) = 0; 8638 8639 /* Now, we call pushtag to put this NEWTAG into the scope of 8640 TYPE. We first set up the IDENTIFIER_TYPE_VALUE to avoid 8641 pushtag calling push_template_decl. We don't have to do 8642 this for enums because it will already have been done in 8643 tsubst_enum. */ 8644 if (name) 8645 SET_IDENTIFIER_TYPE_VALUE (name, newtag); 8646 pushtag (name, newtag, /*tag_scope=*/ts_current); 8647 } 8648 } 8649 else if (TREE_CODE (t) == FUNCTION_DECL 8650 || DECL_FUNCTION_TEMPLATE_P (t)) 8651 { 8652 /* Build new TYPE_METHODS. */ 8653 tree r; 8654 8655 if (TREE_CODE (t) == TEMPLATE_DECL) 8656 ++processing_template_decl; 8657 r = tsubst (t, args, tf_error, NULL_TREE); 8658 if (TREE_CODE (t) == TEMPLATE_DECL) 8659 --processing_template_decl; 8660 set_current_access_from_decl (r); 8661 finish_member_declaration (r); 8662 /* Instantiate members marked with attribute used. */ 8663 if (r != error_mark_node && DECL_PRESERVE_P (r)) 8664 mark_used (r); 8665 } 8666 else 8667 { 8668 /* Build new TYPE_FIELDS. */ 8669 if (TREE_CODE (t) == STATIC_ASSERT) 8670 { 8671 tree condition = 8672 tsubst_expr (STATIC_ASSERT_CONDITION (t), args, 8673 tf_warning_or_error, NULL_TREE, 8674 /*integral_constant_expression_p=*/true); 8675 finish_static_assert (condition, 8676 STATIC_ASSERT_MESSAGE (t), 8677 STATIC_ASSERT_SOURCE_LOCATION (t), 8678 /*member_p=*/true); 8679 } 8680 else if (TREE_CODE (t) != CONST_DECL) 8681 { 8682 tree r; 8683 8684 /* The file and line for this declaration, to 8685 assist in error message reporting. Since we 8686 called push_tinst_level above, we don't need to 8687 restore these. */ 8688 input_location = DECL_SOURCE_LOCATION (t); 8689 8690 if (TREE_CODE (t) == TEMPLATE_DECL) 8691 ++processing_template_decl; 8692 r = tsubst (t, args, tf_warning_or_error, NULL_TREE); 8693 if (TREE_CODE (t) == TEMPLATE_DECL) 8694 --processing_template_decl; 8695 if (TREE_CODE (r) == VAR_DECL) 8696 { 8697 /* In [temp.inst]: 8698 8699 [t]he initialization (and any associated 8700 side-effects) of a static data member does 8701 not occur unless the static data member is 8702 itself used in a way that requires the 8703 definition of the static data member to 8704 exist. 8705 8706 Therefore, we do not substitute into the 8707 initialized for the static data member here. */ 8708 finish_static_data_member_decl 8709 (r, 8710 /*init=*/NULL_TREE, 8711 /*init_const_expr_p=*/false, 8712 /*asmspec_tree=*/NULL_TREE, 8713 /*flags=*/0); 8714 /* Instantiate members marked with attribute used. */ 8715 if (r != error_mark_node && DECL_PRESERVE_P (r)) 8716 mark_used (r); 8717 } 8718 else if (TREE_CODE (r) == FIELD_DECL) 8719 { 8720 /* Determine whether R has a valid type and can be 8721 completed later. If R is invalid, then it is 8722 replaced by error_mark_node so that it will not be 8723 added to TYPE_FIELDS. */ 8724 tree rtype = TREE_TYPE (r); 8725 if (can_complete_type_without_circularity (rtype)) 8726 complete_type (rtype); 8727 8728 if (!COMPLETE_TYPE_P (rtype)) 8729 { 8730 cxx_incomplete_type_error (r, rtype); 8731 r = error_mark_node; 8732 } 8733 } 8734 8735 /* If it is a TYPE_DECL for a class-scoped ENUMERAL_TYPE, 8736 such a thing will already have been added to the field 8737 list by tsubst_enum in finish_member_declaration in the 8738 CLASSTYPE_NESTED_UTDS case above. */ 8739 if (!(TREE_CODE (r) == TYPE_DECL 8740 && TREE_CODE (TREE_TYPE (r)) == ENUMERAL_TYPE 8741 && DECL_ARTIFICIAL (r))) 8742 { 8743 set_current_access_from_decl (r); 8744 finish_member_declaration (r); 8745 } 8746 } 8747 } 8748 } 8749 else 8750 { 8751 if (TYPE_P (t) || DECL_CLASS_TEMPLATE_P (t)) 8752 { 8753 /* Build new CLASSTYPE_FRIEND_CLASSES. */ 8754 8755 tree friend_type = t; 8756 bool adjust_processing_template_decl = false; 8757 8758 if (TREE_CODE (friend_type) == TEMPLATE_DECL) 8759 { 8760 /* template <class T> friend class C; */ 8761 friend_type = tsubst_friend_class (friend_type, args); 8762 adjust_processing_template_decl = true; 8763 } 8764 else if (TREE_CODE (friend_type) == UNBOUND_CLASS_TEMPLATE) 8765 { 8766 /* template <class T> friend class C::D; */ 8767 friend_type = tsubst (friend_type, args, 8768 tf_warning_or_error, NULL_TREE); 8769 if (TREE_CODE (friend_type) == TEMPLATE_DECL) 8770 friend_type = TREE_TYPE (friend_type); 8771 adjust_processing_template_decl = true; 8772 } 8773 else if (TREE_CODE (friend_type) == TYPENAME_TYPE 8774 || TREE_CODE (friend_type) == TEMPLATE_TYPE_PARM) 8775 { 8776 /* This could be either 8777 8778 friend class T::C; 8779 8780 when dependent_type_p is false or 8781 8782 template <class U> friend class T::C; 8783 8784 otherwise. */ 8785 friend_type = tsubst (friend_type, args, 8786 tf_warning_or_error, NULL_TREE); 8787 /* Bump processing_template_decl for correct 8788 dependent_type_p calculation. */ 8789 ++processing_template_decl; 8790 if (dependent_type_p (friend_type)) 8791 adjust_processing_template_decl = true; 8792 --processing_template_decl; 8793 } 8794 else if (!CLASSTYPE_USE_TEMPLATE (friend_type) 8795 && hidden_name_p (TYPE_NAME (friend_type))) 8796 { 8797 /* friend class C; 8798 8799 where C hasn't been declared yet. Let's lookup name 8800 from namespace scope directly, bypassing any name that 8801 come from dependent base class. */ 8802 tree ns = decl_namespace_context (TYPE_MAIN_DECL (friend_type)); 8803 8804 /* The call to xref_tag_from_type does injection for friend 8805 classes. */ 8806 push_nested_namespace (ns); 8807 friend_type = 8808 xref_tag_from_type (friend_type, NULL_TREE, 8809 /*tag_scope=*/ts_current); 8810 pop_nested_namespace (ns); 8811 } 8812 else if (uses_template_parms (friend_type)) 8813 /* friend class C<T>; */ 8814 friend_type = tsubst (friend_type, args, 8815 tf_warning_or_error, NULL_TREE); 8816 /* Otherwise it's 8817 8818 friend class C; 8819 8820 where C is already declared or 8821 8822 friend class C<int>; 8823 8824 We don't have to do anything in these cases. */ 8825 8826 if (adjust_processing_template_decl) 8827 /* Trick make_friend_class into realizing that the friend 8828 we're adding is a template, not an ordinary class. It's 8829 important that we use make_friend_class since it will 8830 perform some error-checking and output cross-reference 8831 information. */ 8832 ++processing_template_decl; 8833 8834 if (friend_type != error_mark_node) 8835 make_friend_class (type, friend_type, /*complain=*/false); 8836 8837 if (adjust_processing_template_decl) 8838 --processing_template_decl; 8839 } 8840 else 8841 { 8842 /* Build new DECL_FRIENDLIST. */ 8843 tree r; 8844 8845 /* The file and line for this declaration, to 8846 assist in error message reporting. Since we 8847 called push_tinst_level above, we don't need to 8848 restore these. */ 8849 input_location = DECL_SOURCE_LOCATION (t); 8850 8851 if (TREE_CODE (t) == TEMPLATE_DECL) 8852 { 8853 ++processing_template_decl; 8854 push_deferring_access_checks (dk_no_check); 8855 } 8856 8857 r = tsubst_friend_function (t, args); 8858 add_friend (type, r, /*complain=*/false); 8859 if (TREE_CODE (t) == TEMPLATE_DECL) 8860 { 8861 pop_deferring_access_checks (); 8862 --processing_template_decl; 8863 } 8864 } 8865 } 8866 } 8867 8868 if (CLASSTYPE_LAMBDA_EXPR (type)) 8869 { 8870 tree decl = lambda_function (type); 8871 if (decl) 8872 { 8873 tree lambda = CLASSTYPE_LAMBDA_EXPR (type); 8874 if (LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (lambda)) 8875 { 8876 apply_lambda_return_type (lambda, void_type_node); 8877 LAMBDA_EXPR_RETURN_TYPE (lambda) = NULL_TREE; 8878 } 8879 8880 instantiate_decl (decl, false, false); 8881 maybe_add_lambda_conv_op (type); 8882 } 8883 else 8884 gcc_assert (errorcount); 8885 } 8886 8887 /* Set the file and line number information to whatever is given for 8888 the class itself. This puts error messages involving generated 8889 implicit functions at a predictable point, and the same point 8890 that would be used for non-template classes. */ 8891 input_location = DECL_SOURCE_LOCATION (typedecl); 8892 8893 unreverse_member_declarations (type); 8894 finish_struct_1 (type); 8895 TYPE_BEING_DEFINED (type) = 0; 8896 8897 /* We don't instantiate default arguments for member functions. 14.7.1: 8898 8899 The implicit instantiation of a class template specialization causes 8900 the implicit instantiation of the declarations, but not of the 8901 definitions or default arguments, of the class member functions, 8902 member classes, static data members and member templates.... */ 8903 8904 /* Some typedefs referenced from within the template code need to be access 8905 checked at template instantiation time, i.e now. These types were 8906 added to the template at parsing time. Let's get those and perform 8907 the access checks then. */ 8908 perform_typedefs_access_check (pattern, args); 8909 perform_deferred_access_checks (); 8910 pop_nested_class (); 8911 maximum_field_alignment = saved_maximum_field_alignment; 8912 if (!fn_context) 8913 pop_from_top_level (); 8914 pop_deferring_access_checks (); 8915 pop_tinst_level (); 8916 8917 /* The vtable for a template class can be emitted in any translation 8918 unit in which the class is instantiated. When there is no key 8919 method, however, finish_struct_1 will already have added TYPE to 8920 the keyed_classes list. */ 8921 if (TYPE_CONTAINS_VPTR_P (type) && CLASSTYPE_KEY_METHOD (type)) 8922 keyed_classes = tree_cons (NULL_TREE, type, keyed_classes); 8923 8924 return type; 8925 } 8926 8927 /* Wrapper for instantiate_class_template_1. */ 8928 8929 tree 8930 instantiate_class_template (tree type) 8931 { 8932 tree ret; 8933 timevar_push (TV_TEMPLATE_INST); 8934 ret = instantiate_class_template_1 (type); 8935 timevar_pop (TV_TEMPLATE_INST); 8936 return ret; 8937 } 8938 8939 static tree 8940 tsubst_template_arg (tree t, tree args, tsubst_flags_t complain, tree in_decl) 8941 { 8942 tree r; 8943 8944 if (!t) 8945 r = t; 8946 else if (TYPE_P (t)) 8947 r = tsubst (t, args, complain, in_decl); 8948 else 8949 { 8950 if (!(complain & tf_warning)) 8951 ++c_inhibit_evaluation_warnings; 8952 r = tsubst_expr (t, args, complain, in_decl, 8953 /*integral_constant_expression_p=*/true); 8954 if (!(complain & tf_warning)) 8955 --c_inhibit_evaluation_warnings; 8956 /* Preserve the raw-reference nature of T. */ 8957 if (TREE_TYPE (t) && TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE 8958 && REFERENCE_REF_P (r)) 8959 r = TREE_OPERAND (r, 0); 8960 } 8961 return r; 8962 } 8963 8964 /* Given a function parameter pack TMPL_PARM and some function parameters 8965 instantiated from it at *SPEC_P, return a NONTYPE_ARGUMENT_PACK of them 8966 and set *SPEC_P to point at the next point in the list. */ 8967 8968 static tree 8969 extract_fnparm_pack (tree tmpl_parm, tree *spec_p) 8970 { 8971 /* Collect all of the extra "packed" parameters into an 8972 argument pack. */ 8973 tree parmvec; 8974 tree parmtypevec; 8975 tree argpack = make_node (NONTYPE_ARGUMENT_PACK); 8976 tree argtypepack = cxx_make_type (TYPE_ARGUMENT_PACK); 8977 tree spec_parm = *spec_p; 8978 int i, len; 8979 8980 for (len = 0; spec_parm; ++len, spec_parm = TREE_CHAIN (spec_parm)) 8981 if (tmpl_parm 8982 && !function_parameter_expanded_from_pack_p (spec_parm, tmpl_parm)) 8983 break; 8984 8985 /* Fill in PARMVEC and PARMTYPEVEC with all of the parameters. */ 8986 parmvec = make_tree_vec (len); 8987 parmtypevec = make_tree_vec (len); 8988 spec_parm = *spec_p; 8989 for (i = 0; i < len; i++, spec_parm = DECL_CHAIN (spec_parm)) 8990 { 8991 TREE_VEC_ELT (parmvec, i) = spec_parm; 8992 TREE_VEC_ELT (parmtypevec, i) = TREE_TYPE (spec_parm); 8993 } 8994 8995 /* Build the argument packs. */ 8996 SET_ARGUMENT_PACK_ARGS (argpack, parmvec); 8997 SET_ARGUMENT_PACK_ARGS (argtypepack, parmtypevec); 8998 TREE_TYPE (argpack) = argtypepack; 8999 *spec_p = spec_parm; 9000 9001 return argpack; 9002 } 9003 9004 /* Give a chain SPEC_PARM of PARM_DECLs, pack them into a 9005 NONTYPE_ARGUMENT_PACK. */ 9006 9007 static tree 9008 make_fnparm_pack (tree spec_parm) 9009 { 9010 return extract_fnparm_pack (NULL_TREE, &spec_parm); 9011 } 9012 9013 /* Substitute ARGS into T, which is an pack expansion 9014 (i.e. TYPE_PACK_EXPANSION or EXPR_PACK_EXPANSION). Returns a 9015 TREE_VEC with the substituted arguments, a PACK_EXPANSION_* node 9016 (if only a partial substitution could be performed) or 9017 ERROR_MARK_NODE if there was an error. */ 9018 tree 9019 tsubst_pack_expansion (tree t, tree args, tsubst_flags_t complain, 9020 tree in_decl) 9021 { 9022 tree pattern; 9023 tree pack, packs = NULL_TREE; 9024 bool unsubstituted_packs = false; 9025 bool real_packs = false; 9026 int missing_level = 0; 9027 int i, len = -1; 9028 tree result; 9029 htab_t saved_local_specializations = NULL; 9030 bool need_local_specializations = false; 9031 int levels; 9032 9033 gcc_assert (PACK_EXPANSION_P (t)); 9034 pattern = PACK_EXPANSION_PATTERN (t); 9035 9036 /* Add in any args remembered from an earlier partial instantiation. */ 9037 args = add_to_template_args (PACK_EXPANSION_EXTRA_ARGS (t), args); 9038 9039 levels = TMPL_ARGS_DEPTH (args); 9040 9041 /* Determine the argument packs that will instantiate the parameter 9042 packs used in the expansion expression. While we're at it, 9043 compute the number of arguments to be expanded and make sure it 9044 is consistent. */ 9045 for (pack = PACK_EXPANSION_PARAMETER_PACKS (t); pack; 9046 pack = TREE_CHAIN (pack)) 9047 { 9048 tree parm_pack = TREE_VALUE (pack); 9049 tree arg_pack = NULL_TREE; 9050 tree orig_arg = NULL_TREE; 9051 int level = 0; 9052 9053 if (TREE_CODE (parm_pack) == BASES) 9054 { 9055 if (BASES_DIRECT (parm_pack)) 9056 return calculate_direct_bases (tsubst_expr (BASES_TYPE (parm_pack), 9057 args, complain, in_decl, false)); 9058 else 9059 return calculate_bases (tsubst_expr (BASES_TYPE (parm_pack), 9060 args, complain, in_decl, false)); 9061 } 9062 if (TREE_CODE (parm_pack) == PARM_DECL) 9063 { 9064 if (PACK_EXPANSION_LOCAL_P (t)) 9065 arg_pack = retrieve_local_specialization (parm_pack); 9066 else 9067 { 9068 /* We can't rely on local_specializations for a parameter 9069 name used later in a function declaration (such as in a 9070 late-specified return type). Even if it exists, it might 9071 have the wrong value for a recursive call. Just make a 9072 dummy decl, since it's only used for its type. */ 9073 /* Copy before tsubsting so that we don't recurse into any 9074 later PARM_DECLs. */ 9075 arg_pack = tsubst_decl (copy_node (parm_pack), args, complain); 9076 if (arg_pack && FUNCTION_PARAMETER_PACK_P (arg_pack)) 9077 /* Partial instantiation of the parm_pack, we can't build 9078 up an argument pack yet. */ 9079 arg_pack = NULL_TREE; 9080 else 9081 arg_pack = make_fnparm_pack (arg_pack); 9082 need_local_specializations = true; 9083 } 9084 } 9085 else 9086 { 9087 int idx; 9088 template_parm_level_and_index (parm_pack, &level, &idx); 9089 9090 if (level <= levels) 9091 arg_pack = TMPL_ARG (args, level, idx); 9092 } 9093 9094 orig_arg = arg_pack; 9095 if (arg_pack && TREE_CODE (arg_pack) == ARGUMENT_PACK_SELECT) 9096 arg_pack = ARGUMENT_PACK_SELECT_FROM_PACK (arg_pack); 9097 9098 if (arg_pack && !ARGUMENT_PACK_P (arg_pack)) 9099 /* This can only happen if we forget to expand an argument 9100 pack somewhere else. Just return an error, silently. */ 9101 { 9102 result = make_tree_vec (1); 9103 TREE_VEC_ELT (result, 0) = error_mark_node; 9104 return result; 9105 } 9106 9107 if (arg_from_parm_pack_p (arg_pack, parm_pack)) 9108 /* The argument pack that the parameter maps to is just an 9109 expansion of the parameter itself, such as one would find 9110 in the implicit typedef of a class inside the class itself. 9111 Consider this parameter "unsubstituted", so that we will 9112 maintain the outer pack expansion. */ 9113 arg_pack = NULL_TREE; 9114 9115 if (arg_pack) 9116 { 9117 int my_len = 9118 TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)); 9119 9120 /* Don't bother trying to do a partial substitution with 9121 incomplete packs; we'll try again after deduction. */ 9122 if (ARGUMENT_PACK_INCOMPLETE_P (arg_pack)) 9123 return t; 9124 9125 if (len < 0) 9126 len = my_len; 9127 else if (len != my_len) 9128 { 9129 if (!(complain & tf_error)) 9130 /* Fail quietly. */; 9131 else if (TREE_CODE (t) == TYPE_PACK_EXPANSION) 9132 error ("mismatched argument pack lengths while expanding " 9133 "%<%T%>", 9134 pattern); 9135 else 9136 error ("mismatched argument pack lengths while expanding " 9137 "%<%E%>", 9138 pattern); 9139 return error_mark_node; 9140 } 9141 9142 if (TREE_VEC_LENGTH (ARGUMENT_PACK_ARGS (arg_pack)) == 1 9143 && PACK_EXPANSION_P (TREE_VEC_ELT (ARGUMENT_PACK_ARGS (arg_pack), 9144 0))) 9145 /* This isn't a real argument pack yet. */; 9146 else 9147 real_packs = true; 9148 9149 /* Keep track of the parameter packs and their corresponding 9150 argument packs. */ 9151 packs = tree_cons (parm_pack, arg_pack, packs); 9152 TREE_TYPE (packs) = orig_arg; 9153 } 9154 else 9155 { 9156 /* We can't substitute for this parameter pack. We use a flag as 9157 well as the missing_level counter because function parameter 9158 packs don't have a level. */ 9159 unsubstituted_packs = true; 9160 if (!missing_level || missing_level > level) 9161 missing_level = level; 9162 } 9163 } 9164 9165 /* We cannot expand this expansion expression, because we don't have 9166 all of the argument packs we need. */ 9167 if (unsubstituted_packs) 9168 { 9169 if (real_packs) 9170 { 9171 /* We got some full packs, but we can't substitute them in until we 9172 have values for all the packs. So remember these until then. */ 9173 tree save_args; 9174 9175 t = make_pack_expansion (pattern); 9176 9177 /* The call to add_to_template_args above assumes no overlap 9178 between saved args and new args, so prune away any fake 9179 args, i.e. those that satisfied arg_from_parm_pack_p above. */ 9180 if (missing_level && levels >= missing_level) 9181 { 9182 gcc_assert (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args) 9183 && missing_level > 1); 9184 TREE_VEC_LENGTH (args) = missing_level - 1; 9185 save_args = copy_node (args); 9186 TREE_VEC_LENGTH (args) = levels; 9187 } 9188 else 9189 save_args = args; 9190 9191 PACK_EXPANSION_EXTRA_ARGS (t) = save_args; 9192 } 9193 else 9194 { 9195 /* There were no real arguments, we're just replacing a parameter 9196 pack with another version of itself. Substitute into the 9197 pattern and return a PACK_EXPANSION_*. The caller will need to 9198 deal with that. */ 9199 if (TREE_CODE (t) == EXPR_PACK_EXPANSION) 9200 t = tsubst_expr (pattern, args, complain, in_decl, 9201 /*integral_constant_expression_p=*/false); 9202 else 9203 t = tsubst (pattern, args, complain, in_decl); 9204 t = make_pack_expansion (t); 9205 } 9206 return t; 9207 } 9208 9209 /* We could not find any argument packs that work. */ 9210 if (len < 0) 9211 return error_mark_node; 9212 9213 if (need_local_specializations) 9214 { 9215 /* We're in a late-specified return type, so create our own local 9216 specializations table; the current table is either NULL or (in the 9217 case of recursive unification) might have bindings that we don't 9218 want to use or alter. */ 9219 saved_local_specializations = local_specializations; 9220 local_specializations = htab_create (37, 9221 hash_local_specialization, 9222 eq_local_specializations, 9223 NULL); 9224 } 9225 9226 /* For each argument in each argument pack, substitute into the 9227 pattern. */ 9228 result = make_tree_vec (len); 9229 for (i = 0; i < len; ++i) 9230 { 9231 /* For parameter pack, change the substitution of the parameter 9232 pack to the ith argument in its argument pack, then expand 9233 the pattern. */ 9234 for (pack = packs; pack; pack = TREE_CHAIN (pack)) 9235 { 9236 tree parm = TREE_PURPOSE (pack); 9237 tree arg; 9238 9239 /* Select the Ith argument from the pack. */ 9240 if (TREE_CODE (parm) == PARM_DECL) 9241 { 9242 if (i == 0) 9243 { 9244 arg = make_node (ARGUMENT_PACK_SELECT); 9245 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack); 9246 mark_used (parm); 9247 register_local_specialization (arg, parm); 9248 } 9249 else 9250 arg = retrieve_local_specialization (parm); 9251 } 9252 else 9253 { 9254 int idx, level; 9255 template_parm_level_and_index (parm, &level, &idx); 9256 9257 if (i == 0) 9258 { 9259 arg = make_node (ARGUMENT_PACK_SELECT); 9260 ARGUMENT_PACK_SELECT_FROM_PACK (arg) = TREE_VALUE (pack); 9261 /* Update the corresponding argument. */ 9262 TMPL_ARG (args, level, idx) = arg; 9263 } 9264 else 9265 /* Re-use the ARGUMENT_PACK_SELECT. */ 9266 arg = TMPL_ARG (args, level, idx); 9267 } 9268 ARGUMENT_PACK_SELECT_INDEX (arg) = i; 9269 } 9270 9271 /* Substitute into the PATTERN with the altered arguments. */ 9272 if (!TYPE_P (pattern)) 9273 TREE_VEC_ELT (result, i) = 9274 tsubst_expr (pattern, args, complain, in_decl, 9275 /*integral_constant_expression_p=*/false); 9276 else 9277 TREE_VEC_ELT (result, i) = tsubst (pattern, args, complain, in_decl); 9278 9279 if (TREE_VEC_ELT (result, i) == error_mark_node) 9280 { 9281 result = error_mark_node; 9282 break; 9283 } 9284 } 9285 9286 /* Update ARGS to restore the substitution from parameter packs to 9287 their argument packs. */ 9288 for (pack = packs; pack; pack = TREE_CHAIN (pack)) 9289 { 9290 tree parm = TREE_PURPOSE (pack); 9291 9292 if (TREE_CODE (parm) == PARM_DECL) 9293 register_local_specialization (TREE_TYPE (pack), parm); 9294 else 9295 { 9296 int idx, level; 9297 template_parm_level_and_index (parm, &level, &idx); 9298 9299 /* Update the corresponding argument. */ 9300 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args)) 9301 TREE_VEC_ELT (TREE_VEC_ELT (args, level -1 ), idx) = 9302 TREE_TYPE (pack); 9303 else 9304 TREE_VEC_ELT (args, idx) = TREE_TYPE (pack); 9305 } 9306 } 9307 9308 if (need_local_specializations) 9309 { 9310 htab_delete (local_specializations); 9311 local_specializations = saved_local_specializations; 9312 } 9313 9314 return result; 9315 } 9316 9317 /* Given PARM_DECL PARM, find the corresponding PARM_DECL in the template 9318 TMPL. We do this using DECL_PARM_INDEX, which should work even with 9319 parameter packs; all parms generated from a function parameter pack will 9320 have the same DECL_PARM_INDEX. */ 9321 9322 tree 9323 get_pattern_parm (tree parm, tree tmpl) 9324 { 9325 tree pattern = DECL_TEMPLATE_RESULT (tmpl); 9326 tree patparm; 9327 9328 if (DECL_ARTIFICIAL (parm)) 9329 { 9330 for (patparm = DECL_ARGUMENTS (pattern); 9331 patparm; patparm = DECL_CHAIN (patparm)) 9332 if (DECL_ARTIFICIAL (patparm) 9333 && DECL_NAME (parm) == DECL_NAME (patparm)) 9334 break; 9335 } 9336 else 9337 { 9338 patparm = FUNCTION_FIRST_USER_PARM (DECL_TEMPLATE_RESULT (tmpl)); 9339 patparm = chain_index (DECL_PARM_INDEX (parm)-1, patparm); 9340 gcc_assert (DECL_PARM_INDEX (patparm) 9341 == DECL_PARM_INDEX (parm)); 9342 } 9343 9344 return patparm; 9345 } 9346 9347 /* Substitute ARGS into the vector or list of template arguments T. */ 9348 9349 static tree 9350 tsubst_template_args (tree t, tree args, tsubst_flags_t complain, tree in_decl) 9351 { 9352 tree orig_t = t; 9353 int len, need_new = 0, i, expanded_len_adjust = 0, out; 9354 tree *elts; 9355 9356 if (t == error_mark_node) 9357 return error_mark_node; 9358 9359 len = TREE_VEC_LENGTH (t); 9360 elts = XALLOCAVEC (tree, len); 9361 9362 for (i = 0; i < len; i++) 9363 { 9364 tree orig_arg = TREE_VEC_ELT (t, i); 9365 tree new_arg; 9366 9367 if (TREE_CODE (orig_arg) == TREE_VEC) 9368 new_arg = tsubst_template_args (orig_arg, args, complain, in_decl); 9369 else if (PACK_EXPANSION_P (orig_arg)) 9370 { 9371 /* Substitute into an expansion expression. */ 9372 new_arg = tsubst_pack_expansion (orig_arg, args, complain, in_decl); 9373 9374 if (TREE_CODE (new_arg) == TREE_VEC) 9375 /* Add to the expanded length adjustment the number of 9376 expanded arguments. We subtract one from this 9377 measurement, because the argument pack expression 9378 itself is already counted as 1 in 9379 LEN. EXPANDED_LEN_ADJUST can actually be negative, if 9380 the argument pack is empty. */ 9381 expanded_len_adjust += TREE_VEC_LENGTH (new_arg) - 1; 9382 } 9383 else if (ARGUMENT_PACK_P (orig_arg)) 9384 { 9385 /* Substitute into each of the arguments. */ 9386 new_arg = TYPE_P (orig_arg) 9387 ? cxx_make_type (TREE_CODE (orig_arg)) 9388 : make_node (TREE_CODE (orig_arg)); 9389 9390 SET_ARGUMENT_PACK_ARGS ( 9391 new_arg, 9392 tsubst_template_args (ARGUMENT_PACK_ARGS (orig_arg), 9393 args, complain, in_decl)); 9394 9395 if (ARGUMENT_PACK_ARGS (new_arg) == error_mark_node) 9396 new_arg = error_mark_node; 9397 9398 if (TREE_CODE (new_arg) == NONTYPE_ARGUMENT_PACK) { 9399 TREE_TYPE (new_arg) = tsubst (TREE_TYPE (orig_arg), args, 9400 complain, in_decl); 9401 TREE_CONSTANT (new_arg) = TREE_CONSTANT (orig_arg); 9402 9403 if (TREE_TYPE (new_arg) == error_mark_node) 9404 new_arg = error_mark_node; 9405 } 9406 } 9407 else 9408 new_arg = tsubst_template_arg (orig_arg, args, complain, in_decl); 9409 9410 if (new_arg == error_mark_node) 9411 return error_mark_node; 9412 9413 elts[i] = new_arg; 9414 if (new_arg != orig_arg) 9415 need_new = 1; 9416 } 9417 9418 if (!need_new) 9419 return t; 9420 9421 /* Make space for the expanded arguments coming from template 9422 argument packs. */ 9423 t = make_tree_vec (len + expanded_len_adjust); 9424 /* ORIG_T can contain TREE_VECs. That happens if ORIG_T contains the 9425 arguments for a member template. 9426 In that case each TREE_VEC in ORIG_T represents a level of template 9427 arguments, and ORIG_T won't carry any non defaulted argument count. 9428 It will rather be the nested TREE_VECs that will carry one. 9429 In other words, ORIG_T carries a non defaulted argument count only 9430 if it doesn't contain any nested TREE_VEC. */ 9431 if (NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t)) 9432 { 9433 int count = GET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (orig_t); 9434 count += expanded_len_adjust; 9435 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (t, count); 9436 } 9437 for (i = 0, out = 0; i < len; i++) 9438 { 9439 if ((PACK_EXPANSION_P (TREE_VEC_ELT (orig_t, i)) 9440 || ARGUMENT_PACK_P (TREE_VEC_ELT (orig_t, i))) 9441 && TREE_CODE (elts[i]) == TREE_VEC) 9442 { 9443 int idx; 9444 9445 /* Now expand the template argument pack "in place". */ 9446 for (idx = 0; idx < TREE_VEC_LENGTH (elts[i]); idx++, out++) 9447 TREE_VEC_ELT (t, out) = TREE_VEC_ELT (elts[i], idx); 9448 } 9449 else 9450 { 9451 TREE_VEC_ELT (t, out) = elts[i]; 9452 out++; 9453 } 9454 } 9455 9456 return t; 9457 } 9458 9459 /* Return the result of substituting ARGS into the template parameters 9460 given by PARMS. If there are m levels of ARGS and m + n levels of 9461 PARMS, then the result will contain n levels of PARMS. For 9462 example, if PARMS is `template <class T> template <class U> 9463 template <T*, U, class V>' and ARGS is {{int}, {double}} then the 9464 result will be `template <int*, double, class V>'. */ 9465 9466 static tree 9467 tsubst_template_parms (tree parms, tree args, tsubst_flags_t complain) 9468 { 9469 tree r = NULL_TREE; 9470 tree* new_parms; 9471 9472 /* When substituting into a template, we must set 9473 PROCESSING_TEMPLATE_DECL as the template parameters may be 9474 dependent if they are based on one-another, and the dependency 9475 predicates are short-circuit outside of templates. */ 9476 ++processing_template_decl; 9477 9478 for (new_parms = &r; 9479 TMPL_PARMS_DEPTH (parms) > TMPL_ARGS_DEPTH (args); 9480 new_parms = &(TREE_CHAIN (*new_parms)), 9481 parms = TREE_CHAIN (parms)) 9482 { 9483 tree new_vec = 9484 make_tree_vec (TREE_VEC_LENGTH (TREE_VALUE (parms))); 9485 int i; 9486 9487 for (i = 0; i < TREE_VEC_LENGTH (new_vec); ++i) 9488 { 9489 tree tuple; 9490 9491 if (parms == error_mark_node) 9492 continue; 9493 9494 tuple = TREE_VEC_ELT (TREE_VALUE (parms), i); 9495 9496 if (tuple == error_mark_node) 9497 continue; 9498 9499 TREE_VEC_ELT (new_vec, i) = 9500 tsubst_template_parm (tuple, args, complain); 9501 } 9502 9503 *new_parms = 9504 tree_cons (size_int (TMPL_PARMS_DEPTH (parms) 9505 - TMPL_ARGS_DEPTH (args)), 9506 new_vec, NULL_TREE); 9507 } 9508 9509 --processing_template_decl; 9510 9511 return r; 9512 } 9513 9514 /* Return the result of substituting ARGS into one template parameter 9515 given by T. T Must be a TREE_LIST which TREE_VALUE is the template 9516 parameter and which TREE_PURPOSE is the default argument of the 9517 template parameter. */ 9518 9519 static tree 9520 tsubst_template_parm (tree t, tree args, tsubst_flags_t complain) 9521 { 9522 tree default_value, parm_decl; 9523 9524 if (args == NULL_TREE 9525 || t == NULL_TREE 9526 || t == error_mark_node) 9527 return t; 9528 9529 gcc_assert (TREE_CODE (t) == TREE_LIST); 9530 9531 default_value = TREE_PURPOSE (t); 9532 parm_decl = TREE_VALUE (t); 9533 9534 parm_decl = tsubst (parm_decl, args, complain, NULL_TREE); 9535 if (TREE_CODE (parm_decl) == PARM_DECL 9536 && invalid_nontype_parm_type_p (TREE_TYPE (parm_decl), complain)) 9537 parm_decl = error_mark_node; 9538 default_value = tsubst_template_arg (default_value, args, 9539 complain, NULL_TREE); 9540 9541 return build_tree_list (default_value, parm_decl); 9542 } 9543 9544 /* Substitute the ARGS into the indicated aggregate (or enumeration) 9545 type T. If T is not an aggregate or enumeration type, it is 9546 handled as if by tsubst. IN_DECL is as for tsubst. If 9547 ENTERING_SCOPE is nonzero, T is the context for a template which 9548 we are presently tsubst'ing. Return the substituted value. */ 9549 9550 static tree 9551 tsubst_aggr_type (tree t, 9552 tree args, 9553 tsubst_flags_t complain, 9554 tree in_decl, 9555 int entering_scope) 9556 { 9557 if (t == NULL_TREE) 9558 return NULL_TREE; 9559 9560 switch (TREE_CODE (t)) 9561 { 9562 case RECORD_TYPE: 9563 if (TYPE_PTRMEMFUNC_P (t)) 9564 return tsubst (TYPE_PTRMEMFUNC_FN_TYPE (t), args, complain, in_decl); 9565 9566 /* Else fall through. */ 9567 case ENUMERAL_TYPE: 9568 case UNION_TYPE: 9569 if (TYPE_TEMPLATE_INFO (t) && uses_template_parms (t)) 9570 { 9571 tree argvec; 9572 tree context; 9573 tree r; 9574 int saved_unevaluated_operand; 9575 int saved_inhibit_evaluation_warnings; 9576 9577 /* In "sizeof(X<I>)" we need to evaluate "I". */ 9578 saved_unevaluated_operand = cp_unevaluated_operand; 9579 cp_unevaluated_operand = 0; 9580 saved_inhibit_evaluation_warnings = c_inhibit_evaluation_warnings; 9581 c_inhibit_evaluation_warnings = 0; 9582 9583 /* First, determine the context for the type we are looking 9584 up. */ 9585 context = TYPE_CONTEXT (t); 9586 if (context && TYPE_P (context)) 9587 { 9588 context = tsubst_aggr_type (context, args, complain, 9589 in_decl, /*entering_scope=*/1); 9590 /* If context is a nested class inside a class template, 9591 it may still need to be instantiated (c++/33959). */ 9592 context = complete_type (context); 9593 } 9594 9595 /* Then, figure out what arguments are appropriate for the 9596 type we are trying to find. For example, given: 9597 9598 template <class T> struct S; 9599 template <class T, class U> void f(T, U) { S<U> su; } 9600 9601 and supposing that we are instantiating f<int, double>, 9602 then our ARGS will be {int, double}, but, when looking up 9603 S we only want {double}. */ 9604 argvec = tsubst_template_args (TYPE_TI_ARGS (t), args, 9605 complain, in_decl); 9606 if (argvec == error_mark_node) 9607 r = error_mark_node; 9608 else 9609 { 9610 r = lookup_template_class (t, argvec, in_decl, context, 9611 entering_scope, complain); 9612 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain); 9613 } 9614 9615 cp_unevaluated_operand = saved_unevaluated_operand; 9616 c_inhibit_evaluation_warnings = saved_inhibit_evaluation_warnings; 9617 9618 return r; 9619 } 9620 else 9621 /* This is not a template type, so there's nothing to do. */ 9622 return t; 9623 9624 default: 9625 return tsubst (t, args, complain, in_decl); 9626 } 9627 } 9628 9629 /* Substitute into the default argument ARG (a default argument for 9630 FN), which has the indicated TYPE. */ 9631 9632 tree 9633 tsubst_default_argument (tree fn, tree type, tree arg) 9634 { 9635 tree saved_class_ptr = NULL_TREE; 9636 tree saved_class_ref = NULL_TREE; 9637 9638 /* This can happen in invalid code. */ 9639 if (TREE_CODE (arg) == DEFAULT_ARG) 9640 return arg; 9641 9642 /* This default argument came from a template. Instantiate the 9643 default argument here, not in tsubst. In the case of 9644 something like: 9645 9646 template <class T> 9647 struct S { 9648 static T t(); 9649 void f(T = t()); 9650 }; 9651 9652 we must be careful to do name lookup in the scope of S<T>, 9653 rather than in the current class. */ 9654 push_access_scope (fn); 9655 /* The "this" pointer is not valid in a default argument. */ 9656 if (cfun) 9657 { 9658 saved_class_ptr = current_class_ptr; 9659 cp_function_chain->x_current_class_ptr = NULL_TREE; 9660 saved_class_ref = current_class_ref; 9661 cp_function_chain->x_current_class_ref = NULL_TREE; 9662 } 9663 9664 push_deferring_access_checks(dk_no_deferred); 9665 /* The default argument expression may cause implicitly defined 9666 member functions to be synthesized, which will result in garbage 9667 collection. We must treat this situation as if we were within 9668 the body of function so as to avoid collecting live data on the 9669 stack. */ 9670 ++function_depth; 9671 arg = tsubst_expr (arg, DECL_TI_ARGS (fn), 9672 tf_warning_or_error, NULL_TREE, 9673 /*integral_constant_expression_p=*/false); 9674 --function_depth; 9675 pop_deferring_access_checks(); 9676 9677 /* Restore the "this" pointer. */ 9678 if (cfun) 9679 { 9680 cp_function_chain->x_current_class_ptr = saved_class_ptr; 9681 cp_function_chain->x_current_class_ref = saved_class_ref; 9682 } 9683 9684 /* Make sure the default argument is reasonable. */ 9685 arg = check_default_argument (type, arg); 9686 9687 pop_access_scope (fn); 9688 9689 return arg; 9690 } 9691 9692 /* Substitute into all the default arguments for FN. */ 9693 9694 static void 9695 tsubst_default_arguments (tree fn) 9696 { 9697 tree arg; 9698 tree tmpl_args; 9699 9700 tmpl_args = DECL_TI_ARGS (fn); 9701 9702 /* If this function is not yet instantiated, we certainly don't need 9703 its default arguments. */ 9704 if (uses_template_parms (tmpl_args)) 9705 return; 9706 /* Don't do this again for clones. */ 9707 if (DECL_CLONED_FUNCTION_P (fn)) 9708 return; 9709 9710 for (arg = TYPE_ARG_TYPES (TREE_TYPE (fn)); 9711 arg; 9712 arg = TREE_CHAIN (arg)) 9713 if (TREE_PURPOSE (arg)) 9714 TREE_PURPOSE (arg) = tsubst_default_argument (fn, 9715 TREE_VALUE (arg), 9716 TREE_PURPOSE (arg)); 9717 } 9718 9719 /* Substitute the ARGS into the T, which is a _DECL. Return the 9720 result of the substitution. Issue error and warning messages under 9721 control of COMPLAIN. */ 9722 9723 static tree 9724 tsubst_decl (tree t, tree args, tsubst_flags_t complain) 9725 { 9726 #define RETURN(EXP) do { r = (EXP); goto out; } while(0) 9727 location_t saved_loc; 9728 tree r = NULL_TREE; 9729 tree in_decl = t; 9730 hashval_t hash = 0; 9731 9732 /* Set the filename and linenumber to improve error-reporting. */ 9733 saved_loc = input_location; 9734 input_location = DECL_SOURCE_LOCATION (t); 9735 9736 switch (TREE_CODE (t)) 9737 { 9738 case TEMPLATE_DECL: 9739 { 9740 /* We can get here when processing a member function template, 9741 member class template, or template template parameter. */ 9742 tree decl = DECL_TEMPLATE_RESULT (t); 9743 tree spec; 9744 tree tmpl_args; 9745 tree full_args; 9746 9747 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)) 9748 { 9749 /* Template template parameter is treated here. */ 9750 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl); 9751 if (new_type == error_mark_node) 9752 RETURN (error_mark_node); 9753 9754 r = copy_decl (t); 9755 DECL_CHAIN (r) = NULL_TREE; 9756 TREE_TYPE (r) = new_type; 9757 DECL_TEMPLATE_RESULT (r) 9758 = build_decl (DECL_SOURCE_LOCATION (decl), 9759 TYPE_DECL, DECL_NAME (decl), new_type); 9760 DECL_TEMPLATE_PARMS (r) 9761 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args, 9762 complain); 9763 TYPE_NAME (new_type) = r; 9764 break; 9765 } 9766 9767 /* We might already have an instance of this template. 9768 The ARGS are for the surrounding class type, so the 9769 full args contain the tsubst'd args for the context, 9770 plus the innermost args from the template decl. */ 9771 tmpl_args = DECL_CLASS_TEMPLATE_P (t) 9772 ? CLASSTYPE_TI_ARGS (TREE_TYPE (t)) 9773 : DECL_TI_ARGS (DECL_TEMPLATE_RESULT (t)); 9774 /* Because this is a template, the arguments will still be 9775 dependent, even after substitution. If 9776 PROCESSING_TEMPLATE_DECL is not set, the dependency 9777 predicates will short-circuit. */ 9778 ++processing_template_decl; 9779 full_args = tsubst_template_args (tmpl_args, args, 9780 complain, in_decl); 9781 --processing_template_decl; 9782 if (full_args == error_mark_node) 9783 RETURN (error_mark_node); 9784 9785 /* If this is a default template template argument, 9786 tsubst might not have changed anything. */ 9787 if (full_args == tmpl_args) 9788 RETURN (t); 9789 9790 hash = hash_tmpl_and_args (t, full_args); 9791 spec = retrieve_specialization (t, full_args, hash); 9792 if (spec != NULL_TREE) 9793 { 9794 r = spec; 9795 break; 9796 } 9797 9798 /* Make a new template decl. It will be similar to the 9799 original, but will record the current template arguments. 9800 We also create a new function declaration, which is just 9801 like the old one, but points to this new template, rather 9802 than the old one. */ 9803 r = copy_decl (t); 9804 gcc_assert (DECL_LANG_SPECIFIC (r) != 0); 9805 DECL_CHAIN (r) = NULL_TREE; 9806 9807 DECL_TEMPLATE_INFO (r) = build_template_info (t, args); 9808 9809 if (TREE_CODE (decl) == TYPE_DECL 9810 && !TYPE_DECL_ALIAS_P (decl)) 9811 { 9812 tree new_type; 9813 ++processing_template_decl; 9814 new_type = tsubst (TREE_TYPE (t), args, complain, in_decl); 9815 --processing_template_decl; 9816 if (new_type == error_mark_node) 9817 RETURN (error_mark_node); 9818 9819 TREE_TYPE (r) = new_type; 9820 CLASSTYPE_TI_TEMPLATE (new_type) = r; 9821 DECL_TEMPLATE_RESULT (r) = TYPE_MAIN_DECL (new_type); 9822 DECL_TI_ARGS (r) = CLASSTYPE_TI_ARGS (new_type); 9823 DECL_CONTEXT (r) = TYPE_CONTEXT (new_type); 9824 } 9825 else 9826 { 9827 tree new_decl; 9828 ++processing_template_decl; 9829 new_decl = tsubst (decl, args, complain, in_decl); 9830 --processing_template_decl; 9831 if (new_decl == error_mark_node) 9832 RETURN (error_mark_node); 9833 9834 DECL_TEMPLATE_RESULT (r) = new_decl; 9835 DECL_TI_TEMPLATE (new_decl) = r; 9836 TREE_TYPE (r) = TREE_TYPE (new_decl); 9837 DECL_TI_ARGS (r) = DECL_TI_ARGS (new_decl); 9838 DECL_CONTEXT (r) = DECL_CONTEXT (new_decl); 9839 } 9840 9841 SET_DECL_IMPLICIT_INSTANTIATION (r); 9842 DECL_TEMPLATE_INSTANTIATIONS (r) = NULL_TREE; 9843 DECL_TEMPLATE_SPECIALIZATIONS (r) = NULL_TREE; 9844 9845 /* The template parameters for this new template are all the 9846 template parameters for the old template, except the 9847 outermost level of parameters. */ 9848 DECL_TEMPLATE_PARMS (r) 9849 = tsubst_template_parms (DECL_TEMPLATE_PARMS (t), args, 9850 complain); 9851 9852 if (PRIMARY_TEMPLATE_P (t)) 9853 DECL_PRIMARY_TEMPLATE (r) = r; 9854 9855 if (TREE_CODE (decl) != TYPE_DECL) 9856 /* Record this non-type partial instantiation. */ 9857 register_specialization (r, t, 9858 DECL_TI_ARGS (DECL_TEMPLATE_RESULT (r)), 9859 false, hash); 9860 } 9861 break; 9862 9863 case FUNCTION_DECL: 9864 { 9865 tree ctx; 9866 tree argvec = NULL_TREE; 9867 tree *friends; 9868 tree gen_tmpl; 9869 tree type; 9870 int member; 9871 int args_depth; 9872 int parms_depth; 9873 9874 /* Nobody should be tsubst'ing into non-template functions. */ 9875 gcc_assert (DECL_TEMPLATE_INFO (t) != NULL_TREE); 9876 9877 if (TREE_CODE (DECL_TI_TEMPLATE (t)) == TEMPLATE_DECL) 9878 { 9879 tree spec; 9880 bool dependent_p; 9881 9882 /* If T is not dependent, just return it. We have to 9883 increment PROCESSING_TEMPLATE_DECL because 9884 value_dependent_expression_p assumes that nothing is 9885 dependent when PROCESSING_TEMPLATE_DECL is zero. */ 9886 ++processing_template_decl; 9887 dependent_p = value_dependent_expression_p (t); 9888 --processing_template_decl; 9889 if (!dependent_p) 9890 RETURN (t); 9891 9892 /* Calculate the most general template of which R is a 9893 specialization, and the complete set of arguments used to 9894 specialize R. */ 9895 gen_tmpl = most_general_template (DECL_TI_TEMPLATE (t)); 9896 argvec = tsubst_template_args (DECL_TI_ARGS 9897 (DECL_TEMPLATE_RESULT 9898 (DECL_TI_TEMPLATE (t))), 9899 args, complain, in_decl); 9900 if (argvec == error_mark_node) 9901 RETURN (error_mark_node); 9902 9903 /* Check to see if we already have this specialization. */ 9904 hash = hash_tmpl_and_args (gen_tmpl, argvec); 9905 spec = retrieve_specialization (gen_tmpl, argvec, hash); 9906 9907 if (spec) 9908 { 9909 r = spec; 9910 break; 9911 } 9912 9913 /* We can see more levels of arguments than parameters if 9914 there was a specialization of a member template, like 9915 this: 9916 9917 template <class T> struct S { template <class U> void f(); } 9918 template <> template <class U> void S<int>::f(U); 9919 9920 Here, we'll be substituting into the specialization, 9921 because that's where we can find the code we actually 9922 want to generate, but we'll have enough arguments for 9923 the most general template. 9924 9925 We also deal with the peculiar case: 9926 9927 template <class T> struct S { 9928 template <class U> friend void f(); 9929 }; 9930 template <class U> void f() {} 9931 template S<int>; 9932 template void f<double>(); 9933 9934 Here, the ARGS for the instantiation of will be {int, 9935 double}. But, we only need as many ARGS as there are 9936 levels of template parameters in CODE_PATTERN. We are 9937 careful not to get fooled into reducing the ARGS in 9938 situations like: 9939 9940 template <class T> struct S { template <class U> void f(U); } 9941 template <class T> template <> void S<T>::f(int) {} 9942 9943 which we can spot because the pattern will be a 9944 specialization in this case. */ 9945 args_depth = TMPL_ARGS_DEPTH (args); 9946 parms_depth = 9947 TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (DECL_TI_TEMPLATE (t))); 9948 if (args_depth > parms_depth 9949 && !DECL_TEMPLATE_SPECIALIZATION (t)) 9950 args = get_innermost_template_args (args, parms_depth); 9951 } 9952 else 9953 { 9954 /* This special case arises when we have something like this: 9955 9956 template <class T> struct S { 9957 friend void f<int>(int, double); 9958 }; 9959 9960 Here, the DECL_TI_TEMPLATE for the friend declaration 9961 will be an IDENTIFIER_NODE. We are being called from 9962 tsubst_friend_function, and we want only to create a 9963 new decl (R) with appropriate types so that we can call 9964 determine_specialization. */ 9965 gen_tmpl = NULL_TREE; 9966 } 9967 9968 if (DECL_CLASS_SCOPE_P (t)) 9969 { 9970 if (DECL_NAME (t) == constructor_name (DECL_CONTEXT (t))) 9971 member = 2; 9972 else 9973 member = 1; 9974 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, 9975 complain, t, /*entering_scope=*/1); 9976 } 9977 else 9978 { 9979 member = 0; 9980 ctx = DECL_CONTEXT (t); 9981 } 9982 type = tsubst (TREE_TYPE (t), args, complain, in_decl); 9983 if (type == error_mark_node) 9984 RETURN (error_mark_node); 9985 9986 /* We do NOT check for matching decls pushed separately at this 9987 point, as they may not represent instantiations of this 9988 template, and in any case are considered separate under the 9989 discrete model. */ 9990 r = copy_decl (t); 9991 DECL_USE_TEMPLATE (r) = 0; 9992 TREE_TYPE (r) = type; 9993 /* Clear out the mangled name and RTL for the instantiation. */ 9994 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE); 9995 SET_DECL_RTL (r, NULL); 9996 /* Leave DECL_INITIAL set on deleted instantiations. */ 9997 if (!DECL_DELETED_FN (r)) 9998 DECL_INITIAL (r) = NULL_TREE; 9999 DECL_CONTEXT (r) = ctx; 10000 10001 if (member && DECL_CONV_FN_P (r)) 10002 /* Type-conversion operator. Reconstruct the name, in 10003 case it's the name of one of the template's parameters. */ 10004 DECL_NAME (r) = mangle_conv_op_name_for_type (TREE_TYPE (type)); 10005 10006 DECL_ARGUMENTS (r) = tsubst (DECL_ARGUMENTS (t), args, 10007 complain, t); 10008 DECL_RESULT (r) = NULL_TREE; 10009 10010 TREE_STATIC (r) = 0; 10011 TREE_PUBLIC (r) = TREE_PUBLIC (t); 10012 DECL_EXTERNAL (r) = 1; 10013 /* If this is an instantiation of a function with internal 10014 linkage, we already know what object file linkage will be 10015 assigned to the instantiation. */ 10016 DECL_INTERFACE_KNOWN (r) = !TREE_PUBLIC (r); 10017 DECL_DEFER_OUTPUT (r) = 0; 10018 DECL_CHAIN (r) = NULL_TREE; 10019 DECL_PENDING_INLINE_INFO (r) = 0; 10020 DECL_PENDING_INLINE_P (r) = 0; 10021 DECL_SAVED_TREE (r) = NULL_TREE; 10022 DECL_STRUCT_FUNCTION (r) = NULL; 10023 TREE_USED (r) = 0; 10024 /* We'll re-clone as appropriate in instantiate_template. */ 10025 DECL_CLONED_FUNCTION (r) = NULL_TREE; 10026 10027 /* If we aren't complaining now, return on error before we register 10028 the specialization so that we'll complain eventually. */ 10029 if ((complain & tf_error) == 0 10030 && IDENTIFIER_OPNAME_P (DECL_NAME (r)) 10031 && !grok_op_properties (r, /*complain=*/false)) 10032 RETURN (error_mark_node); 10033 10034 /* Set up the DECL_TEMPLATE_INFO for R. There's no need to do 10035 this in the special friend case mentioned above where 10036 GEN_TMPL is NULL. */ 10037 if (gen_tmpl) 10038 { 10039 DECL_TEMPLATE_INFO (r) 10040 = build_template_info (gen_tmpl, argvec); 10041 SET_DECL_IMPLICIT_INSTANTIATION (r); 10042 register_specialization (r, gen_tmpl, argvec, false, hash); 10043 10044 /* We're not supposed to instantiate default arguments 10045 until they are called, for a template. But, for a 10046 declaration like: 10047 10048 template <class T> void f () 10049 { extern void g(int i = T()); } 10050 10051 we should do the substitution when the template is 10052 instantiated. We handle the member function case in 10053 instantiate_class_template since the default arguments 10054 might refer to other members of the class. */ 10055 if (!member 10056 && !PRIMARY_TEMPLATE_P (gen_tmpl) 10057 && !uses_template_parms (argvec)) 10058 tsubst_default_arguments (r); 10059 } 10060 else 10061 DECL_TEMPLATE_INFO (r) = NULL_TREE; 10062 10063 /* Copy the list of befriending classes. */ 10064 for (friends = &DECL_BEFRIENDING_CLASSES (r); 10065 *friends; 10066 friends = &TREE_CHAIN (*friends)) 10067 { 10068 *friends = copy_node (*friends); 10069 TREE_VALUE (*friends) = tsubst (TREE_VALUE (*friends), 10070 args, complain, 10071 in_decl); 10072 } 10073 10074 if (DECL_CONSTRUCTOR_P (r) || DECL_DESTRUCTOR_P (r)) 10075 { 10076 maybe_retrofit_in_chrg (r); 10077 if (DECL_CONSTRUCTOR_P (r)) 10078 grok_ctor_properties (ctx, r); 10079 /* If this is an instantiation of a member template, clone it. 10080 If it isn't, that'll be handled by 10081 clone_constructors_and_destructors. */ 10082 if (PRIMARY_TEMPLATE_P (gen_tmpl)) 10083 clone_function_decl (r, /*update_method_vec_p=*/0); 10084 } 10085 else if ((complain & tf_error) != 0 10086 && IDENTIFIER_OPNAME_P (DECL_NAME (r)) 10087 && !grok_op_properties (r, /*complain=*/true)) 10088 RETURN (error_mark_node); 10089 10090 if (DECL_FRIEND_P (t) && DECL_FRIEND_CONTEXT (t)) 10091 SET_DECL_FRIEND_CONTEXT (r, 10092 tsubst (DECL_FRIEND_CONTEXT (t), 10093 args, complain, in_decl)); 10094 10095 /* Possibly limit visibility based on template args. */ 10096 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT; 10097 if (DECL_VISIBILITY_SPECIFIED (t)) 10098 { 10099 DECL_VISIBILITY_SPECIFIED (r) = 0; 10100 DECL_ATTRIBUTES (r) 10101 = remove_attribute ("visibility", DECL_ATTRIBUTES (r)); 10102 } 10103 determine_visibility (r); 10104 if (DECL_DEFAULTED_OUTSIDE_CLASS_P (r) 10105 && !processing_template_decl) 10106 defaulted_late_check (r); 10107 10108 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0, 10109 args, complain, in_decl); 10110 } 10111 break; 10112 10113 case PARM_DECL: 10114 { 10115 tree type = NULL_TREE; 10116 int i, len = 1; 10117 tree expanded_types = NULL_TREE; 10118 tree prev_r = NULL_TREE; 10119 tree first_r = NULL_TREE; 10120 10121 if (FUNCTION_PARAMETER_PACK_P (t)) 10122 { 10123 /* If there is a local specialization that isn't a 10124 parameter pack, it means that we're doing a "simple" 10125 substitution from inside tsubst_pack_expansion. Just 10126 return the local specialization (which will be a single 10127 parm). */ 10128 tree spec = retrieve_local_specialization (t); 10129 if (spec 10130 && TREE_CODE (spec) == PARM_DECL 10131 && TREE_CODE (TREE_TYPE (spec)) != TYPE_PACK_EXPANSION) 10132 RETURN (spec); 10133 10134 /* Expand the TYPE_PACK_EXPANSION that provides the types for 10135 the parameters in this function parameter pack. */ 10136 expanded_types = tsubst_pack_expansion (TREE_TYPE (t), args, 10137 complain, in_decl); 10138 if (TREE_CODE (expanded_types) == TREE_VEC) 10139 { 10140 len = TREE_VEC_LENGTH (expanded_types); 10141 10142 /* Zero-length parameter packs are boring. Just substitute 10143 into the chain. */ 10144 if (len == 0) 10145 RETURN (tsubst (TREE_CHAIN (t), args, complain, 10146 TREE_CHAIN (t))); 10147 } 10148 else 10149 { 10150 /* All we did was update the type. Make a note of that. */ 10151 type = expanded_types; 10152 expanded_types = NULL_TREE; 10153 } 10154 } 10155 10156 /* Loop through all of the parameter's we'll build. When T is 10157 a function parameter pack, LEN is the number of expanded 10158 types in EXPANDED_TYPES; otherwise, LEN is 1. */ 10159 r = NULL_TREE; 10160 for (i = 0; i < len; ++i) 10161 { 10162 prev_r = r; 10163 r = copy_node (t); 10164 if (DECL_TEMPLATE_PARM_P (t)) 10165 SET_DECL_TEMPLATE_PARM_P (r); 10166 10167 if (expanded_types) 10168 /* We're on the Ith parameter of the function parameter 10169 pack. */ 10170 { 10171 /* An argument of a function parameter pack is not a parameter 10172 pack. */ 10173 FUNCTION_PARAMETER_PACK_P (r) = false; 10174 10175 /* Get the Ith type. */ 10176 type = TREE_VEC_ELT (expanded_types, i); 10177 10178 /* Rename the parameter to include the index. */ 10179 DECL_NAME (r) 10180 = make_ith_pack_parameter_name (DECL_NAME (r), i); 10181 } 10182 else if (!type) 10183 /* We're dealing with a normal parameter. */ 10184 type = tsubst (TREE_TYPE (t), args, complain, in_decl); 10185 10186 type = type_decays_to (type); 10187 TREE_TYPE (r) = type; 10188 cp_apply_type_quals_to_decl (cp_type_quals (type), r); 10189 10190 if (DECL_INITIAL (r)) 10191 { 10192 if (TREE_CODE (DECL_INITIAL (r)) != TEMPLATE_PARM_INDEX) 10193 DECL_INITIAL (r) = TREE_TYPE (r); 10194 else 10195 DECL_INITIAL (r) = tsubst (DECL_INITIAL (r), args, 10196 complain, in_decl); 10197 } 10198 10199 DECL_CONTEXT (r) = NULL_TREE; 10200 10201 if (!DECL_TEMPLATE_PARM_P (r)) 10202 DECL_ARG_TYPE (r) = type_passed_as (type); 10203 10204 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0, 10205 args, complain, in_decl); 10206 10207 /* Keep track of the first new parameter we 10208 generate. That's what will be returned to the 10209 caller. */ 10210 if (!first_r) 10211 first_r = r; 10212 10213 /* Build a proper chain of parameters when substituting 10214 into a function parameter pack. */ 10215 if (prev_r) 10216 DECL_CHAIN (prev_r) = r; 10217 } 10218 10219 if (DECL_CHAIN (t)) 10220 DECL_CHAIN (r) = tsubst (DECL_CHAIN (t), args, 10221 complain, DECL_CHAIN (t)); 10222 10223 /* FIRST_R contains the start of the chain we've built. */ 10224 r = first_r; 10225 } 10226 break; 10227 10228 case FIELD_DECL: 10229 { 10230 tree type; 10231 10232 r = copy_decl (t); 10233 type = tsubst (TREE_TYPE (t), args, complain, in_decl); 10234 if (type == error_mark_node) 10235 RETURN (error_mark_node); 10236 TREE_TYPE (r) = type; 10237 cp_apply_type_quals_to_decl (cp_type_quals (type), r); 10238 10239 if (DECL_C_BIT_FIELD (r)) 10240 /* For bit-fields, DECL_INITIAL gives the number of bits. For 10241 non-bit-fields DECL_INITIAL is a non-static data member 10242 initializer, which gets deferred instantiation. */ 10243 DECL_INITIAL (r) 10244 = tsubst_expr (DECL_INITIAL (t), args, 10245 complain, in_decl, 10246 /*integral_constant_expression_p=*/true); 10247 else if (DECL_INITIAL (t)) 10248 { 10249 /* Set up DECL_TEMPLATE_INFO so that we can get at the 10250 NSDMI in perform_member_init. Still set DECL_INITIAL 10251 so that we know there is one. */ 10252 DECL_INITIAL (r) = void_zero_node; 10253 gcc_assert (DECL_LANG_SPECIFIC (r) == NULL); 10254 retrofit_lang_decl (r); 10255 DECL_TEMPLATE_INFO (r) = build_template_info (t, args); 10256 } 10257 /* We don't have to set DECL_CONTEXT here; it is set by 10258 finish_member_declaration. */ 10259 DECL_CHAIN (r) = NULL_TREE; 10260 if (VOID_TYPE_P (type)) 10261 error ("instantiation of %q+D as type %qT", r, type); 10262 10263 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 0, 10264 args, complain, in_decl); 10265 } 10266 break; 10267 10268 case USING_DECL: 10269 /* We reach here only for member using decls. We also need to check 10270 uses_template_parms because DECL_DEPENDENT_P is not set for a 10271 using-declaration that designates a member of the current 10272 instantiation (c++/53549). */ 10273 if (DECL_DEPENDENT_P (t) 10274 || uses_template_parms (USING_DECL_SCOPE (t))) 10275 { 10276 r = do_class_using_decl 10277 (tsubst_copy (USING_DECL_SCOPE (t), args, complain, in_decl), 10278 tsubst_copy (DECL_NAME (t), args, complain, in_decl)); 10279 if (!r) 10280 r = error_mark_node; 10281 else 10282 { 10283 TREE_PROTECTED (r) = TREE_PROTECTED (t); 10284 TREE_PRIVATE (r) = TREE_PRIVATE (t); 10285 } 10286 } 10287 else 10288 { 10289 r = copy_node (t); 10290 DECL_CHAIN (r) = NULL_TREE; 10291 } 10292 break; 10293 10294 case TYPE_DECL: 10295 case VAR_DECL: 10296 { 10297 tree argvec = NULL_TREE; 10298 tree gen_tmpl = NULL_TREE; 10299 tree spec; 10300 tree tmpl = NULL_TREE; 10301 tree ctx; 10302 tree type = NULL_TREE; 10303 bool local_p; 10304 10305 if (TREE_CODE (t) == TYPE_DECL 10306 && t == TYPE_MAIN_DECL (TREE_TYPE (t))) 10307 { 10308 /* If this is the canonical decl, we don't have to 10309 mess with instantiations, and often we can't (for 10310 typename, template type parms and such). Note that 10311 TYPE_NAME is not correct for the above test if 10312 we've copied the type for a typedef. */ 10313 type = tsubst (TREE_TYPE (t), args, complain, in_decl); 10314 if (type == error_mark_node) 10315 RETURN (error_mark_node); 10316 r = TYPE_NAME (type); 10317 break; 10318 } 10319 10320 /* Check to see if we already have the specialization we 10321 need. */ 10322 spec = NULL_TREE; 10323 if (DECL_CLASS_SCOPE_P (t) || DECL_NAMESPACE_SCOPE_P (t)) 10324 { 10325 /* T is a static data member or namespace-scope entity. 10326 We have to substitute into namespace-scope variables 10327 (even though such entities are never templates) because 10328 of cases like: 10329 10330 template <class T> void f() { extern T t; } 10331 10332 where the entity referenced is not known until 10333 instantiation time. */ 10334 local_p = false; 10335 ctx = DECL_CONTEXT (t); 10336 if (DECL_CLASS_SCOPE_P (t)) 10337 { 10338 ctx = tsubst_aggr_type (ctx, args, 10339 complain, 10340 in_decl, /*entering_scope=*/1); 10341 /* If CTX is unchanged, then T is in fact the 10342 specialization we want. That situation occurs when 10343 referencing a static data member within in its own 10344 class. We can use pointer equality, rather than 10345 same_type_p, because DECL_CONTEXT is always 10346 canonical... */ 10347 if (ctx == DECL_CONTEXT (t) 10348 && (TREE_CODE (t) != TYPE_DECL 10349 /* ... unless T is a member template; in which 10350 case our caller can be willing to create a 10351 specialization of that template represented 10352 by T. */ 10353 || !(DECL_TI_TEMPLATE (t) 10354 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (t))))) 10355 spec = t; 10356 } 10357 10358 if (!spec) 10359 { 10360 tmpl = DECL_TI_TEMPLATE (t); 10361 gen_tmpl = most_general_template (tmpl); 10362 argvec = tsubst (DECL_TI_ARGS (t), args, complain, in_decl); 10363 if (argvec == error_mark_node) 10364 RETURN (error_mark_node); 10365 hash = hash_tmpl_and_args (gen_tmpl, argvec); 10366 spec = retrieve_specialization (gen_tmpl, argvec, hash); 10367 } 10368 } 10369 else 10370 { 10371 /* A local variable. */ 10372 local_p = true; 10373 /* Subsequent calls to pushdecl will fill this in. */ 10374 ctx = NULL_TREE; 10375 spec = retrieve_local_specialization (t); 10376 } 10377 /* If we already have the specialization we need, there is 10378 nothing more to do. */ 10379 if (spec) 10380 { 10381 r = spec; 10382 break; 10383 } 10384 10385 if (TREE_CODE (t) == VAR_DECL && DECL_ANON_UNION_VAR_P (t)) 10386 { 10387 /* Just use name lookup to find a member alias for an anonymous 10388 union, but then add it to the hash table. */ 10389 r = lookup_name (DECL_NAME (t)); 10390 gcc_assert (DECL_ANON_UNION_VAR_P (r)); 10391 register_local_specialization (r, t); 10392 break; 10393 } 10394 10395 /* Create a new node for the specialization we need. */ 10396 r = copy_decl (t); 10397 if (type == NULL_TREE) 10398 { 10399 if (is_typedef_decl (t)) 10400 type = DECL_ORIGINAL_TYPE (t); 10401 else 10402 type = TREE_TYPE (t); 10403 if (TREE_CODE (t) == VAR_DECL 10404 && VAR_HAD_UNKNOWN_BOUND (t) 10405 && type != error_mark_node) 10406 type = strip_array_domain (type); 10407 type = tsubst (type, args, complain, in_decl); 10408 } 10409 if (TREE_CODE (r) == VAR_DECL) 10410 { 10411 /* Even if the original location is out of scope, the 10412 newly substituted one is not. */ 10413 DECL_DEAD_FOR_LOCAL (r) = 0; 10414 DECL_INITIALIZED_P (r) = 0; 10415 DECL_TEMPLATE_INSTANTIATED (r) = 0; 10416 if (type == error_mark_node) 10417 RETURN (error_mark_node); 10418 if (TREE_CODE (type) == FUNCTION_TYPE) 10419 { 10420 /* It may seem that this case cannot occur, since: 10421 10422 typedef void f(); 10423 void g() { f x; } 10424 10425 declares a function, not a variable. However: 10426 10427 typedef void f(); 10428 template <typename T> void g() { T t; } 10429 template void g<f>(); 10430 10431 is an attempt to declare a variable with function 10432 type. */ 10433 error ("variable %qD has function type", 10434 /* R is not yet sufficiently initialized, so we 10435 just use its name. */ 10436 DECL_NAME (r)); 10437 RETURN (error_mark_node); 10438 } 10439 type = complete_type (type); 10440 /* Wait until cp_finish_decl to set this again, to handle 10441 circular dependency (template/instantiate6.C). */ 10442 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (r) = 0; 10443 type = check_var_type (DECL_NAME (r), type); 10444 10445 if (DECL_HAS_VALUE_EXPR_P (t)) 10446 { 10447 tree ve = DECL_VALUE_EXPR (t); 10448 ve = tsubst_expr (ve, args, complain, in_decl, 10449 /*constant_expression_p=*/false); 10450 if (REFERENCE_REF_P (ve)) 10451 { 10452 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE); 10453 ve = TREE_OPERAND (ve, 0); 10454 } 10455 SET_DECL_VALUE_EXPR (r, ve); 10456 } 10457 } 10458 else if (DECL_SELF_REFERENCE_P (t)) 10459 SET_DECL_SELF_REFERENCE_P (r); 10460 TREE_TYPE (r) = type; 10461 cp_apply_type_quals_to_decl (cp_type_quals (type), r); 10462 DECL_CONTEXT (r) = ctx; 10463 /* Clear out the mangled name and RTL for the instantiation. */ 10464 SET_DECL_ASSEMBLER_NAME (r, NULL_TREE); 10465 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL)) 10466 SET_DECL_RTL (r, NULL); 10467 /* The initializer must not be expanded until it is required; 10468 see [temp.inst]. */ 10469 DECL_INITIAL (r) = NULL_TREE; 10470 if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL)) 10471 SET_DECL_RTL (r, NULL); 10472 DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0; 10473 if (TREE_CODE (r) == VAR_DECL) 10474 { 10475 /* Possibly limit visibility based on template args. */ 10476 DECL_VISIBILITY (r) = VISIBILITY_DEFAULT; 10477 if (DECL_VISIBILITY_SPECIFIED (t)) 10478 { 10479 DECL_VISIBILITY_SPECIFIED (r) = 0; 10480 DECL_ATTRIBUTES (r) 10481 = remove_attribute ("visibility", DECL_ATTRIBUTES (r)); 10482 } 10483 determine_visibility (r); 10484 } 10485 10486 if (!local_p) 10487 { 10488 /* A static data member declaration is always marked 10489 external when it is declared in-class, even if an 10490 initializer is present. We mimic the non-template 10491 processing here. */ 10492 DECL_EXTERNAL (r) = 1; 10493 10494 register_specialization (r, gen_tmpl, argvec, false, hash); 10495 DECL_TEMPLATE_INFO (r) = build_template_info (tmpl, argvec); 10496 SET_DECL_IMPLICIT_INSTANTIATION (r); 10497 } 10498 else if (cp_unevaluated_operand) 10499 { 10500 /* We're substituting this var in a decltype outside of its 10501 scope, such as for a lambda return type. Don't add it to 10502 local_specializations, do perform auto deduction. */ 10503 tree auto_node = type_uses_auto (type); 10504 if (auto_node) 10505 { 10506 tree init 10507 = tsubst_expr (DECL_INITIAL (t), args, complain, in_decl, 10508 /*constant_expression_p=*/false); 10509 init = resolve_nondeduced_context (init); 10510 TREE_TYPE (r) = type 10511 = do_auto_deduction (type, init, auto_node); 10512 } 10513 } 10514 else 10515 register_local_specialization (r, t); 10516 10517 DECL_CHAIN (r) = NULL_TREE; 10518 10519 apply_late_template_attributes (&r, DECL_ATTRIBUTES (r), 10520 /*flags=*/0, 10521 args, complain, in_decl); 10522 10523 /* Preserve a typedef that names a type. */ 10524 if (is_typedef_decl (r)) 10525 { 10526 DECL_ORIGINAL_TYPE (r) = NULL_TREE; 10527 set_underlying_type (r); 10528 } 10529 10530 layout_decl (r, 0); 10531 } 10532 break; 10533 10534 default: 10535 gcc_unreachable (); 10536 } 10537 #undef RETURN 10538 10539 out: 10540 /* Restore the file and line information. */ 10541 input_location = saved_loc; 10542 10543 return r; 10544 } 10545 10546 /* Substitute into the ARG_TYPES of a function type. 10547 If END is a TREE_CHAIN, leave it and any following types 10548 un-substituted. */ 10549 10550 static tree 10551 tsubst_arg_types (tree arg_types, 10552 tree args, 10553 tree end, 10554 tsubst_flags_t complain, 10555 tree in_decl) 10556 { 10557 tree remaining_arg_types; 10558 tree type = NULL_TREE; 10559 int i = 1; 10560 tree expanded_args = NULL_TREE; 10561 tree default_arg; 10562 10563 if (!arg_types || arg_types == void_list_node || arg_types == end) 10564 return arg_types; 10565 10566 remaining_arg_types = tsubst_arg_types (TREE_CHAIN (arg_types), 10567 args, end, complain, in_decl); 10568 if (remaining_arg_types == error_mark_node) 10569 return error_mark_node; 10570 10571 if (PACK_EXPANSION_P (TREE_VALUE (arg_types))) 10572 { 10573 /* For a pack expansion, perform substitution on the 10574 entire expression. Later on, we'll handle the arguments 10575 one-by-one. */ 10576 expanded_args = tsubst_pack_expansion (TREE_VALUE (arg_types), 10577 args, complain, in_decl); 10578 10579 if (TREE_CODE (expanded_args) == TREE_VEC) 10580 /* So that we'll spin through the parameters, one by one. */ 10581 i = TREE_VEC_LENGTH (expanded_args); 10582 else 10583 { 10584 /* We only partially substituted into the parameter 10585 pack. Our type is TYPE_PACK_EXPANSION. */ 10586 type = expanded_args; 10587 expanded_args = NULL_TREE; 10588 } 10589 } 10590 10591 while (i > 0) { 10592 --i; 10593 10594 if (expanded_args) 10595 type = TREE_VEC_ELT (expanded_args, i); 10596 else if (!type) 10597 type = tsubst (TREE_VALUE (arg_types), args, complain, in_decl); 10598 10599 if (type == error_mark_node) 10600 return error_mark_node; 10601 if (VOID_TYPE_P (type)) 10602 { 10603 if (complain & tf_error) 10604 { 10605 error ("invalid parameter type %qT", type); 10606 if (in_decl) 10607 error ("in declaration %q+D", in_decl); 10608 } 10609 return error_mark_node; 10610 } 10611 10612 /* Do array-to-pointer, function-to-pointer conversion, and ignore 10613 top-level qualifiers as required. */ 10614 type = cv_unqualified (type_decays_to (type)); 10615 10616 /* We do not substitute into default arguments here. The standard 10617 mandates that they be instantiated only when needed, which is 10618 done in build_over_call. */ 10619 default_arg = TREE_PURPOSE (arg_types); 10620 10621 if (default_arg && TREE_CODE (default_arg) == DEFAULT_ARG) 10622 { 10623 /* We've instantiated a template before its default arguments 10624 have been parsed. This can happen for a nested template 10625 class, and is not an error unless we require the default 10626 argument in a call of this function. */ 10627 remaining_arg_types = 10628 tree_cons (default_arg, type, remaining_arg_types); 10629 VEC_safe_push (tree, gc, DEFARG_INSTANTIATIONS (default_arg), 10630 remaining_arg_types); 10631 } 10632 else 10633 remaining_arg_types = 10634 hash_tree_cons (default_arg, type, remaining_arg_types); 10635 } 10636 10637 return remaining_arg_types; 10638 } 10639 10640 /* Substitute into a FUNCTION_TYPE or METHOD_TYPE. This routine does 10641 *not* handle the exception-specification for FNTYPE, because the 10642 initial substitution of explicitly provided template parameters 10643 during argument deduction forbids substitution into the 10644 exception-specification: 10645 10646 [temp.deduct] 10647 10648 All references in the function type of the function template to the 10649 corresponding template parameters are replaced by the specified tem- 10650 plate argument values. If a substitution in a template parameter or 10651 in the function type of the function template results in an invalid 10652 type, type deduction fails. [Note: The equivalent substitution in 10653 exception specifications is done only when the function is instanti- 10654 ated, at which point a program is ill-formed if the substitution 10655 results in an invalid type.] */ 10656 10657 static tree 10658 tsubst_function_type (tree t, 10659 tree args, 10660 tsubst_flags_t complain, 10661 tree in_decl) 10662 { 10663 tree return_type; 10664 tree arg_types; 10665 tree fntype; 10666 10667 /* The TYPE_CONTEXT is not used for function/method types. */ 10668 gcc_assert (TYPE_CONTEXT (t) == NULL_TREE); 10669 10670 /* Substitute the return type. */ 10671 return_type = tsubst (TREE_TYPE (t), args, complain, in_decl); 10672 if (return_type == error_mark_node) 10673 return error_mark_node; 10674 /* The standard does not presently indicate that creation of a 10675 function type with an invalid return type is a deduction failure. 10676 However, that is clearly analogous to creating an array of "void" 10677 or a reference to a reference. This is core issue #486. */ 10678 if (TREE_CODE (return_type) == ARRAY_TYPE 10679 || TREE_CODE (return_type) == FUNCTION_TYPE) 10680 { 10681 if (complain & tf_error) 10682 { 10683 if (TREE_CODE (return_type) == ARRAY_TYPE) 10684 error ("function returning an array"); 10685 else 10686 error ("function returning a function"); 10687 } 10688 return error_mark_node; 10689 } 10690 10691 /* Substitute the argument types. */ 10692 arg_types = tsubst_arg_types (TYPE_ARG_TYPES (t), args, NULL_TREE, 10693 complain, in_decl); 10694 if (arg_types == error_mark_node) 10695 return error_mark_node; 10696 10697 /* Construct a new type node and return it. */ 10698 if (TREE_CODE (t) == FUNCTION_TYPE) 10699 { 10700 fntype = build_function_type (return_type, arg_types); 10701 fntype = apply_memfn_quals (fntype, type_memfn_quals (t)); 10702 } 10703 else 10704 { 10705 tree r = TREE_TYPE (TREE_VALUE (arg_types)); 10706 if (! MAYBE_CLASS_TYPE_P (r)) 10707 { 10708 /* [temp.deduct] 10709 10710 Type deduction may fail for any of the following 10711 reasons: 10712 10713 -- Attempting to create "pointer to member of T" when T 10714 is not a class type. */ 10715 if (complain & tf_error) 10716 error ("creating pointer to member function of non-class type %qT", 10717 r); 10718 return error_mark_node; 10719 } 10720 10721 fntype = build_method_type_directly (r, return_type, 10722 TREE_CHAIN (arg_types)); 10723 } 10724 fntype = cp_build_type_attribute_variant (fntype, TYPE_ATTRIBUTES (t)); 10725 10726 return fntype; 10727 } 10728 10729 /* FNTYPE is a FUNCTION_TYPE or METHOD_TYPE. Substitute the template 10730 ARGS into that specification, and return the substituted 10731 specification. If there is no specification, return NULL_TREE. */ 10732 10733 static tree 10734 tsubst_exception_specification (tree fntype, 10735 tree args, 10736 tsubst_flags_t complain, 10737 tree in_decl, 10738 bool defer_ok) 10739 { 10740 tree specs; 10741 tree new_specs; 10742 10743 specs = TYPE_RAISES_EXCEPTIONS (fntype); 10744 new_specs = NULL_TREE; 10745 if (specs && TREE_PURPOSE (specs)) 10746 { 10747 /* A noexcept-specifier. */ 10748 tree expr = TREE_PURPOSE (specs); 10749 if (TREE_CODE (expr) == INTEGER_CST) 10750 new_specs = expr; 10751 else if (defer_ok) 10752 { 10753 /* Defer instantiation of noexcept-specifiers to avoid 10754 excessive instantiations (c++/49107). */ 10755 new_specs = make_node (DEFERRED_NOEXCEPT); 10756 if (DEFERRED_NOEXCEPT_SPEC_P (specs)) 10757 { 10758 /* We already partially instantiated this member template, 10759 so combine the new args with the old. */ 10760 DEFERRED_NOEXCEPT_PATTERN (new_specs) 10761 = DEFERRED_NOEXCEPT_PATTERN (expr); 10762 DEFERRED_NOEXCEPT_ARGS (new_specs) 10763 = add_to_template_args (DEFERRED_NOEXCEPT_ARGS (expr), args); 10764 } 10765 else 10766 { 10767 DEFERRED_NOEXCEPT_PATTERN (new_specs) = expr; 10768 DEFERRED_NOEXCEPT_ARGS (new_specs) = args; 10769 } 10770 } 10771 else 10772 new_specs = tsubst_copy_and_build 10773 (expr, args, complain, in_decl, /*function_p=*/false, 10774 /*integral_constant_expression_p=*/true); 10775 new_specs = build_noexcept_spec (new_specs, complain); 10776 } 10777 else if (specs) 10778 { 10779 if (! TREE_VALUE (specs)) 10780 new_specs = specs; 10781 else 10782 while (specs) 10783 { 10784 tree spec; 10785 int i, len = 1; 10786 tree expanded_specs = NULL_TREE; 10787 10788 if (PACK_EXPANSION_P (TREE_VALUE (specs))) 10789 { 10790 /* Expand the pack expansion type. */ 10791 expanded_specs = tsubst_pack_expansion (TREE_VALUE (specs), 10792 args, complain, 10793 in_decl); 10794 10795 if (expanded_specs == error_mark_node) 10796 return error_mark_node; 10797 else if (TREE_CODE (expanded_specs) == TREE_VEC) 10798 len = TREE_VEC_LENGTH (expanded_specs); 10799 else 10800 { 10801 /* We're substituting into a member template, so 10802 we got a TYPE_PACK_EXPANSION back. Add that 10803 expansion and move on. */ 10804 gcc_assert (TREE_CODE (expanded_specs) 10805 == TYPE_PACK_EXPANSION); 10806 new_specs = add_exception_specifier (new_specs, 10807 expanded_specs, 10808 complain); 10809 specs = TREE_CHAIN (specs); 10810 continue; 10811 } 10812 } 10813 10814 for (i = 0; i < len; ++i) 10815 { 10816 if (expanded_specs) 10817 spec = TREE_VEC_ELT (expanded_specs, i); 10818 else 10819 spec = tsubst (TREE_VALUE (specs), args, complain, in_decl); 10820 if (spec == error_mark_node) 10821 return spec; 10822 new_specs = add_exception_specifier (new_specs, spec, 10823 complain); 10824 } 10825 10826 specs = TREE_CHAIN (specs); 10827 } 10828 } 10829 return new_specs; 10830 } 10831 10832 /* Take the tree structure T and replace template parameters used 10833 therein with the argument vector ARGS. IN_DECL is an associated 10834 decl for diagnostics. If an error occurs, returns ERROR_MARK_NODE. 10835 Issue error and warning messages under control of COMPLAIN. Note 10836 that we must be relatively non-tolerant of extensions here, in 10837 order to preserve conformance; if we allow substitutions that 10838 should not be allowed, we may allow argument deductions that should 10839 not succeed, and therefore report ambiguous overload situations 10840 where there are none. In theory, we could allow the substitution, 10841 but indicate that it should have failed, and allow our caller to 10842 make sure that the right thing happens, but we don't try to do this 10843 yet. 10844 10845 This function is used for dealing with types, decls and the like; 10846 for expressions, use tsubst_expr or tsubst_copy. */ 10847 10848 tree 10849 tsubst (tree t, tree args, tsubst_flags_t complain, tree in_decl) 10850 { 10851 enum tree_code code; 10852 tree type, r = NULL_TREE; 10853 10854 if (t == NULL_TREE || t == error_mark_node 10855 || t == integer_type_node 10856 || t == void_type_node 10857 || t == char_type_node 10858 || t == unknown_type_node 10859 || TREE_CODE (t) == NAMESPACE_DECL 10860 || TREE_CODE (t) == TRANSLATION_UNIT_DECL) 10861 return t; 10862 10863 if (DECL_P (t)) 10864 return tsubst_decl (t, args, complain); 10865 10866 if (args == NULL_TREE) 10867 return t; 10868 10869 code = TREE_CODE (t); 10870 10871 if (code == IDENTIFIER_NODE) 10872 type = IDENTIFIER_TYPE_VALUE (t); 10873 else 10874 type = TREE_TYPE (t); 10875 10876 gcc_assert (type != unknown_type_node); 10877 10878 /* Reuse typedefs. We need to do this to handle dependent attributes, 10879 such as attribute aligned. */ 10880 if (TYPE_P (t) 10881 && typedef_variant_p (t)) 10882 { 10883 tree decl = TYPE_NAME (t); 10884 10885 if (TYPE_DECL_ALIAS_P (decl) 10886 && DECL_LANG_SPECIFIC (decl) 10887 && DECL_TEMPLATE_INFO (decl) 10888 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl))) 10889 { 10890 /* DECL represents an alias template and we want to 10891 instantiate it. Let's substitute our arguments for the 10892 template parameters into the declaration and get the 10893 resulting type. */ 10894 r = tsubst (decl, args, complain, decl); 10895 } 10896 else if (DECL_CLASS_SCOPE_P (decl) 10897 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl)) 10898 && uses_template_parms (DECL_CONTEXT (decl))) 10899 { 10900 tree tmpl = most_general_template (DECL_TI_TEMPLATE (decl)); 10901 tree gen_args = tsubst (DECL_TI_ARGS (decl), args, complain, in_decl); 10902 r = retrieve_specialization (tmpl, gen_args, 0); 10903 } 10904 else if (DECL_FUNCTION_SCOPE_P (decl) 10905 && DECL_TEMPLATE_INFO (DECL_CONTEXT (decl)) 10906 && uses_template_parms (DECL_TI_ARGS (DECL_CONTEXT (decl)))) 10907 r = retrieve_local_specialization (decl); 10908 else 10909 /* The typedef is from a non-template context. */ 10910 return t; 10911 10912 if (r) 10913 { 10914 r = TREE_TYPE (r); 10915 r = cp_build_qualified_type_real 10916 (r, cp_type_quals (t) | cp_type_quals (r), 10917 complain | tf_ignore_bad_quals); 10918 return r; 10919 } 10920 else 10921 { 10922 /* We don't have an instantiation yet, so drop the typedef. */ 10923 int quals = cp_type_quals (t); 10924 t = DECL_ORIGINAL_TYPE (decl); 10925 t = cp_build_qualified_type_real (t, quals, 10926 complain | tf_ignore_bad_quals); 10927 } 10928 } 10929 10930 if (type 10931 && code != TYPENAME_TYPE 10932 && code != TEMPLATE_TYPE_PARM 10933 && code != IDENTIFIER_NODE 10934 && code != FUNCTION_TYPE 10935 && code != METHOD_TYPE) 10936 type = tsubst (type, args, complain, in_decl); 10937 if (type == error_mark_node) 10938 return error_mark_node; 10939 10940 switch (code) 10941 { 10942 case RECORD_TYPE: 10943 case UNION_TYPE: 10944 case ENUMERAL_TYPE: 10945 return tsubst_aggr_type (t, args, complain, in_decl, 10946 /*entering_scope=*/0); 10947 10948 case ERROR_MARK: 10949 case IDENTIFIER_NODE: 10950 case VOID_TYPE: 10951 case REAL_TYPE: 10952 case COMPLEX_TYPE: 10953 case VECTOR_TYPE: 10954 case BOOLEAN_TYPE: 10955 case NULLPTR_TYPE: 10956 case LANG_TYPE: 10957 return t; 10958 10959 case INTEGER_TYPE: 10960 if (t == integer_type_node) 10961 return t; 10962 10963 if (TREE_CODE (TYPE_MIN_VALUE (t)) == INTEGER_CST 10964 && TREE_CODE (TYPE_MAX_VALUE (t)) == INTEGER_CST) 10965 return t; 10966 10967 { 10968 tree max, omax = TREE_OPERAND (TYPE_MAX_VALUE (t), 0); 10969 10970 max = tsubst_expr (omax, args, complain, in_decl, 10971 /*integral_constant_expression_p=*/false); 10972 10973 /* Fix up type of the magic NOP_EXPR with TREE_SIDE_EFFECTS if 10974 needed. */ 10975 if (TREE_CODE (max) == NOP_EXPR 10976 && TREE_SIDE_EFFECTS (omax) 10977 && !TREE_TYPE (max)) 10978 TREE_TYPE (max) = TREE_TYPE (TREE_OPERAND (max, 0)); 10979 10980 /* If we're in a partial instantiation, preserve the magic NOP_EXPR 10981 with TREE_SIDE_EFFECTS that indicates this is not an integral 10982 constant expression. */ 10983 if (processing_template_decl 10984 && TREE_SIDE_EFFECTS (omax) && TREE_CODE (omax) == NOP_EXPR) 10985 { 10986 gcc_assert (TREE_CODE (max) == NOP_EXPR); 10987 TREE_SIDE_EFFECTS (max) = 1; 10988 } 10989 10990 return compute_array_index_type (NULL_TREE, max, complain); 10991 } 10992 10993 case TEMPLATE_TYPE_PARM: 10994 case TEMPLATE_TEMPLATE_PARM: 10995 case BOUND_TEMPLATE_TEMPLATE_PARM: 10996 case TEMPLATE_PARM_INDEX: 10997 { 10998 int idx; 10999 int level; 11000 int levels; 11001 tree arg = NULL_TREE; 11002 11003 r = NULL_TREE; 11004 11005 gcc_assert (TREE_VEC_LENGTH (args) > 0); 11006 template_parm_level_and_index (t, &level, &idx); 11007 11008 levels = TMPL_ARGS_DEPTH (args); 11009 if (level <= levels) 11010 { 11011 arg = TMPL_ARG (args, level, idx); 11012 11013 if (arg && TREE_CODE (arg) == ARGUMENT_PACK_SELECT) 11014 /* See through ARGUMENT_PACK_SELECT arguments. */ 11015 arg = ARGUMENT_PACK_SELECT_ARG (arg); 11016 } 11017 11018 if (arg == error_mark_node) 11019 return error_mark_node; 11020 else if (arg != NULL_TREE) 11021 { 11022 if (ARGUMENT_PACK_P (arg)) 11023 /* If ARG is an argument pack, we don't actually want to 11024 perform a substitution here, because substitutions 11025 for argument packs are only done 11026 element-by-element. We can get to this point when 11027 substituting the type of a non-type template 11028 parameter pack, when that type actually contains 11029 template parameter packs from an outer template, e.g., 11030 11031 template<typename... Types> struct A { 11032 template<Types... Values> struct B { }; 11033 }; */ 11034 return t; 11035 11036 if (code == TEMPLATE_TYPE_PARM) 11037 { 11038 int quals; 11039 gcc_assert (TYPE_P (arg)); 11040 11041 quals = cp_type_quals (arg) | cp_type_quals (t); 11042 11043 return cp_build_qualified_type_real 11044 (arg, quals, complain | tf_ignore_bad_quals); 11045 } 11046 else if (code == BOUND_TEMPLATE_TEMPLATE_PARM) 11047 { 11048 /* We are processing a type constructed from a 11049 template template parameter. */ 11050 tree argvec = tsubst (TYPE_TI_ARGS (t), 11051 args, complain, in_decl); 11052 if (argvec == error_mark_node) 11053 return error_mark_node; 11054 11055 gcc_assert (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM 11056 || TREE_CODE (arg) == TEMPLATE_DECL 11057 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE); 11058 11059 if (TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE) 11060 /* Consider this code: 11061 11062 template <template <class> class Template> 11063 struct Internal { 11064 template <class Arg> using Bind = Template<Arg>; 11065 }; 11066 11067 template <template <class> class Template, class Arg> 11068 using Instantiate = Template<Arg>; //#0 11069 11070 template <template <class> class Template, 11071 class Argument> 11072 using Bind = 11073 Instantiate<Internal<Template>::template Bind, 11074 Argument>; //#1 11075 11076 When #1 is parsed, the 11077 BOUND_TEMPLATE_TEMPLATE_PARM representing the 11078 parameter `Template' in #0 matches the 11079 UNBOUND_CLASS_TEMPLATE representing the argument 11080 `Internal<Template>::template Bind'; We then want 11081 to assemble the type `Bind<Argument>' that can't 11082 be fully created right now, because 11083 `Internal<Template>' not being complete, the Bind 11084 template cannot be looked up in that context. So 11085 we need to "store" `Bind<Argument>' for later 11086 when the context of Bind becomes complete. Let's 11087 store that in a TYPENAME_TYPE. */ 11088 return make_typename_type (TYPE_CONTEXT (arg), 11089 build_nt (TEMPLATE_ID_EXPR, 11090 TYPE_IDENTIFIER (arg), 11091 argvec), 11092 typename_type, 11093 complain); 11094 11095 /* We can get a TEMPLATE_TEMPLATE_PARM here when we 11096 are resolving nested-types in the signature of a 11097 member function templates. Otherwise ARG is a 11098 TEMPLATE_DECL and is the real template to be 11099 instantiated. */ 11100 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM) 11101 arg = TYPE_NAME (arg); 11102 11103 r = lookup_template_class (arg, 11104 argvec, in_decl, 11105 DECL_CONTEXT (arg), 11106 /*entering_scope=*/0, 11107 complain); 11108 return cp_build_qualified_type_real 11109 (r, cp_type_quals (t), complain); 11110 } 11111 else 11112 /* TEMPLATE_TEMPLATE_PARM or TEMPLATE_PARM_INDEX. */ 11113 return convert_from_reference (unshare_expr (arg)); 11114 } 11115 11116 if (level == 1) 11117 /* This can happen during the attempted tsubst'ing in 11118 unify. This means that we don't yet have any information 11119 about the template parameter in question. */ 11120 return t; 11121 11122 /* If we get here, we must have been looking at a parm for a 11123 more deeply nested template. Make a new version of this 11124 template parameter, but with a lower level. */ 11125 switch (code) 11126 { 11127 case TEMPLATE_TYPE_PARM: 11128 case TEMPLATE_TEMPLATE_PARM: 11129 case BOUND_TEMPLATE_TEMPLATE_PARM: 11130 if (cp_type_quals (t)) 11131 { 11132 r = tsubst (TYPE_MAIN_VARIANT (t), args, complain, in_decl); 11133 r = cp_build_qualified_type_real 11134 (r, cp_type_quals (t), 11135 complain | (code == TEMPLATE_TYPE_PARM 11136 ? tf_ignore_bad_quals : 0)); 11137 } 11138 else 11139 { 11140 r = copy_type (t); 11141 TEMPLATE_TYPE_PARM_INDEX (r) 11142 = reduce_template_parm_level (TEMPLATE_TYPE_PARM_INDEX (t), 11143 r, levels, args, complain); 11144 TYPE_STUB_DECL (r) = TYPE_NAME (r) = TEMPLATE_TYPE_DECL (r); 11145 TYPE_MAIN_VARIANT (r) = r; 11146 TYPE_POINTER_TO (r) = NULL_TREE; 11147 TYPE_REFERENCE_TO (r) = NULL_TREE; 11148 11149 if (TREE_CODE (r) == TEMPLATE_TEMPLATE_PARM) 11150 /* We have reduced the level of the template 11151 template parameter, but not the levels of its 11152 template parameters, so canonical_type_parameter 11153 will not be able to find the canonical template 11154 template parameter for this level. Thus, we 11155 require structural equality checking to compare 11156 TEMPLATE_TEMPLATE_PARMs. */ 11157 SET_TYPE_STRUCTURAL_EQUALITY (r); 11158 else if (TYPE_STRUCTURAL_EQUALITY_P (t)) 11159 SET_TYPE_STRUCTURAL_EQUALITY (r); 11160 else 11161 TYPE_CANONICAL (r) = canonical_type_parameter (r); 11162 11163 if (code == BOUND_TEMPLATE_TEMPLATE_PARM) 11164 { 11165 tree argvec = tsubst (TYPE_TI_ARGS (t), args, 11166 complain, in_decl); 11167 if (argvec == error_mark_node) 11168 return error_mark_node; 11169 11170 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (r) 11171 = build_template_info (TYPE_TI_TEMPLATE (t), argvec); 11172 } 11173 } 11174 break; 11175 11176 case TEMPLATE_PARM_INDEX: 11177 r = reduce_template_parm_level (t, type, levels, args, complain); 11178 break; 11179 11180 default: 11181 gcc_unreachable (); 11182 } 11183 11184 return r; 11185 } 11186 11187 case TREE_LIST: 11188 { 11189 tree purpose, value, chain; 11190 11191 if (t == void_list_node) 11192 return t; 11193 11194 purpose = TREE_PURPOSE (t); 11195 if (purpose) 11196 { 11197 purpose = tsubst (purpose, args, complain, in_decl); 11198 if (purpose == error_mark_node) 11199 return error_mark_node; 11200 } 11201 value = TREE_VALUE (t); 11202 if (value) 11203 { 11204 value = tsubst (value, args, complain, in_decl); 11205 if (value == error_mark_node) 11206 return error_mark_node; 11207 } 11208 chain = TREE_CHAIN (t); 11209 if (chain && chain != void_type_node) 11210 { 11211 chain = tsubst (chain, args, complain, in_decl); 11212 if (chain == error_mark_node) 11213 return error_mark_node; 11214 } 11215 if (purpose == TREE_PURPOSE (t) 11216 && value == TREE_VALUE (t) 11217 && chain == TREE_CHAIN (t)) 11218 return t; 11219 return hash_tree_cons (purpose, value, chain); 11220 } 11221 11222 case TREE_BINFO: 11223 /* We should never be tsubsting a binfo. */ 11224 gcc_unreachable (); 11225 11226 case TREE_VEC: 11227 /* A vector of template arguments. */ 11228 gcc_assert (!type); 11229 return tsubst_template_args (t, args, complain, in_decl); 11230 11231 case POINTER_TYPE: 11232 case REFERENCE_TYPE: 11233 { 11234 if (type == TREE_TYPE (t) && TREE_CODE (type) != METHOD_TYPE) 11235 return t; 11236 11237 /* [temp.deduct] 11238 11239 Type deduction may fail for any of the following 11240 reasons: 11241 11242 -- Attempting to create a pointer to reference type. 11243 -- Attempting to create a reference to a reference type or 11244 a reference to void. 11245 11246 Core issue 106 says that creating a reference to a reference 11247 during instantiation is no longer a cause for failure. We 11248 only enforce this check in strict C++98 mode. */ 11249 if ((TREE_CODE (type) == REFERENCE_TYPE 11250 && (((cxx_dialect == cxx98) && flag_iso) || code != REFERENCE_TYPE)) 11251 || (code == REFERENCE_TYPE && TREE_CODE (type) == VOID_TYPE)) 11252 { 11253 static location_t last_loc; 11254 11255 /* We keep track of the last time we issued this error 11256 message to avoid spewing a ton of messages during a 11257 single bad template instantiation. */ 11258 if (complain & tf_error 11259 && last_loc != input_location) 11260 { 11261 if (TREE_CODE (type) == VOID_TYPE) 11262 error ("forming reference to void"); 11263 else if (code == POINTER_TYPE) 11264 error ("forming pointer to reference type %qT", type); 11265 else 11266 error ("forming reference to reference type %qT", type); 11267 last_loc = input_location; 11268 } 11269 11270 return error_mark_node; 11271 } 11272 else if (code == POINTER_TYPE) 11273 { 11274 r = build_pointer_type (type); 11275 if (TREE_CODE (type) == METHOD_TYPE) 11276 r = build_ptrmemfunc_type (r); 11277 } 11278 else if (TREE_CODE (type) == REFERENCE_TYPE) 11279 /* In C++0x, during template argument substitution, when there is an 11280 attempt to create a reference to a reference type, reference 11281 collapsing is applied as described in [14.3.1/4 temp.arg.type]: 11282 11283 "If a template-argument for a template-parameter T names a type 11284 that is a reference to a type A, an attempt to create the type 11285 'lvalue reference to cv T' creates the type 'lvalue reference to 11286 A,' while an attempt to create the type type rvalue reference to 11287 cv T' creates the type T" 11288 */ 11289 r = cp_build_reference_type 11290 (TREE_TYPE (type), 11291 TYPE_REF_IS_RVALUE (t) && TYPE_REF_IS_RVALUE (type)); 11292 else 11293 r = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t)); 11294 r = cp_build_qualified_type_real (r, cp_type_quals (t), complain); 11295 11296 if (r != error_mark_node) 11297 /* Will this ever be needed for TYPE_..._TO values? */ 11298 layout_type (r); 11299 11300 return r; 11301 } 11302 case OFFSET_TYPE: 11303 { 11304 r = tsubst (TYPE_OFFSET_BASETYPE (t), args, complain, in_decl); 11305 if (r == error_mark_node || !MAYBE_CLASS_TYPE_P (r)) 11306 { 11307 /* [temp.deduct] 11308 11309 Type deduction may fail for any of the following 11310 reasons: 11311 11312 -- Attempting to create "pointer to member of T" when T 11313 is not a class type. */ 11314 if (complain & tf_error) 11315 error ("creating pointer to member of non-class type %qT", r); 11316 return error_mark_node; 11317 } 11318 if (TREE_CODE (type) == REFERENCE_TYPE) 11319 { 11320 if (complain & tf_error) 11321 error ("creating pointer to member reference type %qT", type); 11322 return error_mark_node; 11323 } 11324 if (TREE_CODE (type) == VOID_TYPE) 11325 { 11326 if (complain & tf_error) 11327 error ("creating pointer to member of type void"); 11328 return error_mark_node; 11329 } 11330 gcc_assert (TREE_CODE (type) != METHOD_TYPE); 11331 if (TREE_CODE (type) == FUNCTION_TYPE) 11332 { 11333 /* The type of the implicit object parameter gets its 11334 cv-qualifiers from the FUNCTION_TYPE. */ 11335 tree memptr; 11336 tree method_type = build_memfn_type (type, r, type_memfn_quals (type)); 11337 memptr = build_ptrmemfunc_type (build_pointer_type (method_type)); 11338 return cp_build_qualified_type_real (memptr, cp_type_quals (t), 11339 complain); 11340 } 11341 else 11342 return cp_build_qualified_type_real (build_ptrmem_type (r, type), 11343 cp_type_quals (t), 11344 complain); 11345 } 11346 case FUNCTION_TYPE: 11347 case METHOD_TYPE: 11348 { 11349 tree fntype; 11350 tree specs; 11351 fntype = tsubst_function_type (t, args, complain, in_decl); 11352 if (fntype == error_mark_node) 11353 return error_mark_node; 11354 11355 /* Substitute the exception specification. */ 11356 specs = tsubst_exception_specification (t, args, complain, 11357 in_decl, /*defer_ok*/true); 11358 if (specs == error_mark_node) 11359 return error_mark_node; 11360 if (specs) 11361 fntype = build_exception_variant (fntype, specs); 11362 return fntype; 11363 } 11364 case ARRAY_TYPE: 11365 { 11366 tree domain = tsubst (TYPE_DOMAIN (t), args, complain, in_decl); 11367 if (domain == error_mark_node) 11368 return error_mark_node; 11369 11370 /* As an optimization, we avoid regenerating the array type if 11371 it will obviously be the same as T. */ 11372 if (type == TREE_TYPE (t) && domain == TYPE_DOMAIN (t)) 11373 return t; 11374 11375 /* These checks should match the ones in grokdeclarator. 11376 11377 [temp.deduct] 11378 11379 The deduction may fail for any of the following reasons: 11380 11381 -- Attempting to create an array with an element type that 11382 is void, a function type, or a reference type, or [DR337] 11383 an abstract class type. */ 11384 if (TREE_CODE (type) == VOID_TYPE 11385 || TREE_CODE (type) == FUNCTION_TYPE 11386 || TREE_CODE (type) == REFERENCE_TYPE) 11387 { 11388 if (complain & tf_error) 11389 error ("creating array of %qT", type); 11390 return error_mark_node; 11391 } 11392 if (CLASS_TYPE_P (type) && CLASSTYPE_PURE_VIRTUALS (type)) 11393 { 11394 if (complain & tf_error) 11395 error ("creating array of %qT, which is an abstract class type", 11396 type); 11397 return error_mark_node; 11398 } 11399 11400 r = build_cplus_array_type (type, domain); 11401 11402 if (TYPE_USER_ALIGN (t)) 11403 { 11404 TYPE_ALIGN (r) = TYPE_ALIGN (t); 11405 TYPE_USER_ALIGN (r) = 1; 11406 } 11407 11408 return r; 11409 } 11410 11411 case TYPENAME_TYPE: 11412 { 11413 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain, 11414 in_decl, /*entering_scope=*/1); 11415 tree f = tsubst_copy (TYPENAME_TYPE_FULLNAME (t), args, 11416 complain, in_decl); 11417 11418 if (ctx == error_mark_node || f == error_mark_node) 11419 return error_mark_node; 11420 11421 if (!MAYBE_CLASS_TYPE_P (ctx)) 11422 { 11423 if (complain & tf_error) 11424 error ("%qT is not a class, struct, or union type", ctx); 11425 return error_mark_node; 11426 } 11427 else if (!uses_template_parms (ctx) && !TYPE_BEING_DEFINED (ctx)) 11428 { 11429 /* Normally, make_typename_type does not require that the CTX 11430 have complete type in order to allow things like: 11431 11432 template <class T> struct S { typename S<T>::X Y; }; 11433 11434 But, such constructs have already been resolved by this 11435 point, so here CTX really should have complete type, unless 11436 it's a partial instantiation. */ 11437 ctx = complete_type (ctx); 11438 if (!COMPLETE_TYPE_P (ctx)) 11439 { 11440 if (complain & tf_error) 11441 cxx_incomplete_type_error (NULL_TREE, ctx); 11442 return error_mark_node; 11443 } 11444 } 11445 11446 f = make_typename_type (ctx, f, typename_type, 11447 (complain & tf_error) | tf_keep_type_decl); 11448 if (f == error_mark_node) 11449 return f; 11450 if (TREE_CODE (f) == TYPE_DECL) 11451 { 11452 complain |= tf_ignore_bad_quals; 11453 f = TREE_TYPE (f); 11454 } 11455 11456 if (TREE_CODE (f) != TYPENAME_TYPE) 11457 { 11458 if (TYPENAME_IS_ENUM_P (t) && TREE_CODE (f) != ENUMERAL_TYPE) 11459 { 11460 if (complain & tf_error) 11461 error ("%qT resolves to %qT, which is not an enumeration type", 11462 t, f); 11463 else 11464 return error_mark_node; 11465 } 11466 else if (TYPENAME_IS_CLASS_P (t) && !CLASS_TYPE_P (f)) 11467 { 11468 if (complain & tf_error) 11469 error ("%qT resolves to %qT, which is is not a class type", 11470 t, f); 11471 else 11472 return error_mark_node; 11473 } 11474 } 11475 11476 return cp_build_qualified_type_real 11477 (f, cp_type_quals (f) | cp_type_quals (t), complain); 11478 } 11479 11480 case UNBOUND_CLASS_TEMPLATE: 11481 { 11482 tree ctx = tsubst_aggr_type (TYPE_CONTEXT (t), args, complain, 11483 in_decl, /*entering_scope=*/1); 11484 tree name = TYPE_IDENTIFIER (t); 11485 tree parm_list = DECL_TEMPLATE_PARMS (TYPE_NAME (t)); 11486 11487 if (ctx == error_mark_node || name == error_mark_node) 11488 return error_mark_node; 11489 11490 if (parm_list) 11491 parm_list = tsubst_template_parms (parm_list, args, complain); 11492 return make_unbound_class_template (ctx, name, parm_list, complain); 11493 } 11494 11495 case TYPEOF_TYPE: 11496 { 11497 tree type; 11498 11499 ++cp_unevaluated_operand; 11500 ++c_inhibit_evaluation_warnings; 11501 11502 type = tsubst_expr (TYPEOF_TYPE_EXPR (t), args, 11503 complain, in_decl, 11504 /*integral_constant_expression_p=*/false); 11505 11506 --cp_unevaluated_operand; 11507 --c_inhibit_evaluation_warnings; 11508 11509 type = finish_typeof (type); 11510 return cp_build_qualified_type_real (type, 11511 cp_type_quals (t) 11512 | cp_type_quals (type), 11513 complain); 11514 } 11515 11516 case DECLTYPE_TYPE: 11517 { 11518 tree type; 11519 11520 ++cp_unevaluated_operand; 11521 ++c_inhibit_evaluation_warnings; 11522 11523 type = tsubst_expr (DECLTYPE_TYPE_EXPR (t), args, 11524 complain, in_decl, 11525 /*integral_constant_expression_p=*/false); 11526 11527 --cp_unevaluated_operand; 11528 --c_inhibit_evaluation_warnings; 11529 11530 if (DECLTYPE_FOR_LAMBDA_CAPTURE (t)) 11531 type = lambda_capture_field_type (type); 11532 else if (DECLTYPE_FOR_LAMBDA_PROXY (t)) 11533 type = lambda_proxy_type (type); 11534 else 11535 type = finish_decltype_type 11536 (type, DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t), complain); 11537 return cp_build_qualified_type_real (type, 11538 cp_type_quals (t) 11539 | cp_type_quals (type), 11540 complain); 11541 } 11542 11543 case UNDERLYING_TYPE: 11544 { 11545 tree type = tsubst (UNDERLYING_TYPE_TYPE (t), args, 11546 complain, in_decl); 11547 return finish_underlying_type (type); 11548 } 11549 11550 case TYPE_ARGUMENT_PACK: 11551 case NONTYPE_ARGUMENT_PACK: 11552 { 11553 tree r = TYPE_P (t) ? cxx_make_type (code) : make_node (code); 11554 tree packed_out = 11555 tsubst_template_args (ARGUMENT_PACK_ARGS (t), 11556 args, 11557 complain, 11558 in_decl); 11559 SET_ARGUMENT_PACK_ARGS (r, packed_out); 11560 11561 /* For template nontype argument packs, also substitute into 11562 the type. */ 11563 if (code == NONTYPE_ARGUMENT_PACK) 11564 TREE_TYPE (r) = tsubst (TREE_TYPE (t), args, complain, in_decl); 11565 11566 return r; 11567 } 11568 break; 11569 11570 case INTEGER_CST: 11571 case REAL_CST: 11572 case STRING_CST: 11573 case PLUS_EXPR: 11574 case MINUS_EXPR: 11575 case NEGATE_EXPR: 11576 case NOP_EXPR: 11577 case INDIRECT_REF: 11578 case ADDR_EXPR: 11579 case CALL_EXPR: 11580 case ARRAY_REF: 11581 case SCOPE_REF: 11582 /* We should use one of the expression tsubsts for these codes. */ 11583 gcc_unreachable (); 11584 11585 default: 11586 sorry ("use of %qs in template", tree_code_name [(int) code]); 11587 return error_mark_node; 11588 } 11589 } 11590 11591 /* Like tsubst_expr for a BASELINK. OBJECT_TYPE, if non-NULL, is the 11592 type of the expression on the left-hand side of the "." or "->" 11593 operator. */ 11594 11595 static tree 11596 tsubst_baselink (tree baselink, tree object_type, 11597 tree args, tsubst_flags_t complain, tree in_decl) 11598 { 11599 tree name; 11600 tree qualifying_scope; 11601 tree fns; 11602 tree optype; 11603 tree template_args = 0; 11604 bool template_id_p = false; 11605 bool qualified = BASELINK_QUALIFIED_P (baselink); 11606 11607 /* A baselink indicates a function from a base class. Both the 11608 BASELINK_ACCESS_BINFO and the base class referenced may 11609 indicate bases of the template class, rather than the 11610 instantiated class. In addition, lookups that were not 11611 ambiguous before may be ambiguous now. Therefore, we perform 11612 the lookup again. */ 11613 qualifying_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (baselink)); 11614 qualifying_scope = tsubst (qualifying_scope, args, 11615 complain, in_decl); 11616 fns = BASELINK_FUNCTIONS (baselink); 11617 optype = tsubst (BASELINK_OPTYPE (baselink), args, complain, in_decl); 11618 if (TREE_CODE (fns) == TEMPLATE_ID_EXPR) 11619 { 11620 template_id_p = true; 11621 template_args = TREE_OPERAND (fns, 1); 11622 fns = TREE_OPERAND (fns, 0); 11623 if (template_args) 11624 template_args = tsubst_template_args (template_args, args, 11625 complain, in_decl); 11626 } 11627 name = DECL_NAME (get_first_fn (fns)); 11628 if (IDENTIFIER_TYPENAME_P (name)) 11629 name = mangle_conv_op_name_for_type (optype); 11630 baselink = lookup_fnfields (qualifying_scope, name, /*protect=*/1); 11631 if (!baselink) 11632 return error_mark_node; 11633 11634 /* If lookup found a single function, mark it as used at this 11635 point. (If it lookup found multiple functions the one selected 11636 later by overload resolution will be marked as used at that 11637 point.) */ 11638 if (BASELINK_P (baselink)) 11639 fns = BASELINK_FUNCTIONS (baselink); 11640 if (!template_id_p && !really_overloaded_fn (fns)) 11641 mark_used (OVL_CURRENT (fns)); 11642 11643 /* Add back the template arguments, if present. */ 11644 if (BASELINK_P (baselink) && template_id_p) 11645 BASELINK_FUNCTIONS (baselink) 11646 = build_nt (TEMPLATE_ID_EXPR, 11647 BASELINK_FUNCTIONS (baselink), 11648 template_args); 11649 /* Update the conversion operator type. */ 11650 BASELINK_OPTYPE (baselink) = optype; 11651 11652 if (!object_type) 11653 object_type = current_class_type; 11654 11655 if (qualified) 11656 baselink = adjust_result_of_qualified_name_lookup (baselink, 11657 qualifying_scope, 11658 object_type); 11659 return baselink; 11660 } 11661 11662 /* Like tsubst_expr for a SCOPE_REF, given by QUALIFIED_ID. DONE is 11663 true if the qualified-id will be a postfix-expression in-and-of 11664 itself; false if more of the postfix-expression follows the 11665 QUALIFIED_ID. ADDRESS_P is true if the qualified-id is the operand 11666 of "&". */ 11667 11668 static tree 11669 tsubst_qualified_id (tree qualified_id, tree args, 11670 tsubst_flags_t complain, tree in_decl, 11671 bool done, bool address_p) 11672 { 11673 tree expr; 11674 tree scope; 11675 tree name; 11676 bool is_template; 11677 tree template_args; 11678 11679 gcc_assert (TREE_CODE (qualified_id) == SCOPE_REF); 11680 11681 /* Figure out what name to look up. */ 11682 name = TREE_OPERAND (qualified_id, 1); 11683 if (TREE_CODE (name) == TEMPLATE_ID_EXPR) 11684 { 11685 is_template = true; 11686 template_args = TREE_OPERAND (name, 1); 11687 if (template_args) 11688 template_args = tsubst_template_args (template_args, args, 11689 complain, in_decl); 11690 name = TREE_OPERAND (name, 0); 11691 } 11692 else 11693 { 11694 is_template = false; 11695 template_args = NULL_TREE; 11696 } 11697 11698 /* Substitute into the qualifying scope. When there are no ARGS, we 11699 are just trying to simplify a non-dependent expression. In that 11700 case the qualifying scope may be dependent, and, in any case, 11701 substituting will not help. */ 11702 scope = TREE_OPERAND (qualified_id, 0); 11703 if (args) 11704 { 11705 scope = tsubst (scope, args, complain, in_decl); 11706 expr = tsubst_copy (name, args, complain, in_decl); 11707 } 11708 else 11709 expr = name; 11710 11711 if (dependent_scope_p (scope)) 11712 { 11713 if (is_template) 11714 expr = build_min_nt (TEMPLATE_ID_EXPR, expr, template_args); 11715 return build_qualified_name (NULL_TREE, scope, expr, 11716 QUALIFIED_NAME_IS_TEMPLATE (qualified_id)); 11717 } 11718 11719 if (!BASELINK_P (name) && !DECL_P (expr)) 11720 { 11721 if (TREE_CODE (expr) == BIT_NOT_EXPR) 11722 { 11723 /* A BIT_NOT_EXPR is used to represent a destructor. */ 11724 if (!check_dtor_name (scope, TREE_OPERAND (expr, 0))) 11725 { 11726 error ("qualifying type %qT does not match destructor name ~%qT", 11727 scope, TREE_OPERAND (expr, 0)); 11728 expr = error_mark_node; 11729 } 11730 else 11731 expr = lookup_qualified_name (scope, complete_dtor_identifier, 11732 /*is_type_p=*/0, false); 11733 } 11734 else 11735 expr = lookup_qualified_name (scope, expr, /*is_type_p=*/0, false); 11736 if (TREE_CODE (TREE_CODE (expr) == TEMPLATE_DECL 11737 ? DECL_TEMPLATE_RESULT (expr) : expr) == TYPE_DECL) 11738 { 11739 if (complain & tf_error) 11740 { 11741 error ("dependent-name %qE is parsed as a non-type, but " 11742 "instantiation yields a type", qualified_id); 11743 inform (input_location, "say %<typename %E%> if a type is meant", qualified_id); 11744 } 11745 return error_mark_node; 11746 } 11747 } 11748 11749 if (DECL_P (expr)) 11750 { 11751 check_accessibility_of_qualified_id (expr, /*object_type=*/NULL_TREE, 11752 scope); 11753 /* Remember that there was a reference to this entity. */ 11754 mark_used (expr); 11755 } 11756 11757 if (expr == error_mark_node || TREE_CODE (expr) == TREE_LIST) 11758 { 11759 if (complain & tf_error) 11760 qualified_name_lookup_error (scope, 11761 TREE_OPERAND (qualified_id, 1), 11762 expr, input_location); 11763 return error_mark_node; 11764 } 11765 11766 if (is_template) 11767 expr = lookup_template_function (expr, template_args); 11768 11769 if (expr == error_mark_node && complain & tf_error) 11770 qualified_name_lookup_error (scope, TREE_OPERAND (qualified_id, 1), 11771 expr, input_location); 11772 else if (TYPE_P (scope)) 11773 { 11774 expr = (adjust_result_of_qualified_name_lookup 11775 (expr, scope, current_class_type)); 11776 expr = (finish_qualified_id_expr 11777 (scope, expr, done, address_p && PTRMEM_OK_P (qualified_id), 11778 QUALIFIED_NAME_IS_TEMPLATE (qualified_id), 11779 /*template_arg_p=*/false)); 11780 } 11781 11782 /* Expressions do not generally have reference type. */ 11783 if (TREE_CODE (expr) != SCOPE_REF 11784 /* However, if we're about to form a pointer-to-member, we just 11785 want the referenced member referenced. */ 11786 && TREE_CODE (expr) != OFFSET_REF) 11787 expr = convert_from_reference (expr); 11788 11789 return expr; 11790 } 11791 11792 /* Like tsubst, but deals with expressions. This function just replaces 11793 template parms; to finish processing the resultant expression, use 11794 tsubst_copy_and_build or tsubst_expr. */ 11795 11796 static tree 11797 tsubst_copy (tree t, tree args, tsubst_flags_t complain, tree in_decl) 11798 { 11799 enum tree_code code; 11800 tree r; 11801 11802 if (t == NULL_TREE || t == error_mark_node || args == NULL_TREE) 11803 return t; 11804 11805 code = TREE_CODE (t); 11806 11807 switch (code) 11808 { 11809 case PARM_DECL: 11810 r = retrieve_local_specialization (t); 11811 11812 if (r == NULL) 11813 { 11814 tree c; 11815 11816 /* We get here for a use of 'this' in an NSDMI. */ 11817 if (DECL_NAME (t) == this_identifier 11818 && at_function_scope_p () 11819 && DECL_CONSTRUCTOR_P (current_function_decl)) 11820 return current_class_ptr; 11821 11822 /* This can happen for a parameter name used later in a function 11823 declaration (such as in a late-specified return type). Just 11824 make a dummy decl, since it's only used for its type. */ 11825 gcc_assert (cp_unevaluated_operand != 0); 11826 /* We copy T because want to tsubst the PARM_DECL only, 11827 not the following PARM_DECLs that are chained to T. */ 11828 c = copy_node (t); 11829 r = tsubst_decl (c, args, complain); 11830 /* Give it the template pattern as its context; its true context 11831 hasn't been instantiated yet and this is good enough for 11832 mangling. */ 11833 DECL_CONTEXT (r) = DECL_CONTEXT (t); 11834 } 11835 11836 if (TREE_CODE (r) == ARGUMENT_PACK_SELECT) 11837 r = ARGUMENT_PACK_SELECT_ARG (r); 11838 mark_used (r); 11839 return r; 11840 11841 case CONST_DECL: 11842 { 11843 tree enum_type; 11844 tree v; 11845 11846 if (DECL_TEMPLATE_PARM_P (t)) 11847 return tsubst_copy (DECL_INITIAL (t), args, complain, in_decl); 11848 /* There is no need to substitute into namespace-scope 11849 enumerators. */ 11850 if (DECL_NAMESPACE_SCOPE_P (t)) 11851 return t; 11852 /* If ARGS is NULL, then T is known to be non-dependent. */ 11853 if (args == NULL_TREE) 11854 return integral_constant_value (t); 11855 11856 /* Unfortunately, we cannot just call lookup_name here. 11857 Consider: 11858 11859 template <int I> int f() { 11860 enum E { a = I }; 11861 struct S { void g() { E e = a; } }; 11862 }; 11863 11864 When we instantiate f<7>::S::g(), say, lookup_name is not 11865 clever enough to find f<7>::a. */ 11866 enum_type 11867 = tsubst_aggr_type (TREE_TYPE (t), args, complain, in_decl, 11868 /*entering_scope=*/0); 11869 11870 for (v = TYPE_VALUES (enum_type); 11871 v != NULL_TREE; 11872 v = TREE_CHAIN (v)) 11873 if (TREE_PURPOSE (v) == DECL_NAME (t)) 11874 return TREE_VALUE (v); 11875 11876 /* We didn't find the name. That should never happen; if 11877 name-lookup found it during preliminary parsing, we 11878 should find it again here during instantiation. */ 11879 gcc_unreachable (); 11880 } 11881 return t; 11882 11883 case FIELD_DECL: 11884 if (DECL_CONTEXT (t)) 11885 { 11886 tree ctx; 11887 11888 ctx = tsubst_aggr_type (DECL_CONTEXT (t), args, complain, in_decl, 11889 /*entering_scope=*/1); 11890 if (ctx != DECL_CONTEXT (t)) 11891 { 11892 tree r = lookup_field (ctx, DECL_NAME (t), 0, false); 11893 if (!r) 11894 { 11895 if (complain & tf_error) 11896 error ("using invalid field %qD", t); 11897 return error_mark_node; 11898 } 11899 return r; 11900 } 11901 } 11902 11903 return t; 11904 11905 case VAR_DECL: 11906 case FUNCTION_DECL: 11907 if ((DECL_LANG_SPECIFIC (t) && DECL_TEMPLATE_INFO (t)) 11908 || local_variable_p (t)) 11909 t = tsubst (t, args, complain, in_decl); 11910 mark_used (t); 11911 return t; 11912 11913 case NAMESPACE_DECL: 11914 return t; 11915 11916 case OVERLOAD: 11917 /* An OVERLOAD will always be a non-dependent overload set; an 11918 overload set from function scope will just be represented with an 11919 IDENTIFIER_NODE, and from class scope with a BASELINK. */ 11920 gcc_assert (!uses_template_parms (t)); 11921 return t; 11922 11923 case BASELINK: 11924 return tsubst_baselink (t, current_class_type, args, complain, in_decl); 11925 11926 case TEMPLATE_DECL: 11927 if (DECL_TEMPLATE_TEMPLATE_PARM_P (t)) 11928 return tsubst (TREE_TYPE (DECL_TEMPLATE_RESULT (t)), 11929 args, complain, in_decl); 11930 else if (DECL_FUNCTION_TEMPLATE_P (t) && DECL_MEMBER_TEMPLATE_P (t)) 11931 return tsubst (t, args, complain, in_decl); 11932 else if (DECL_CLASS_SCOPE_P (t) 11933 && uses_template_parms (DECL_CONTEXT (t))) 11934 { 11935 /* Template template argument like the following example need 11936 special treatment: 11937 11938 template <template <class> class TT> struct C {}; 11939 template <class T> struct D { 11940 template <class U> struct E {}; 11941 C<E> c; // #1 11942 }; 11943 D<int> d; // #2 11944 11945 We are processing the template argument `E' in #1 for 11946 the template instantiation #2. Originally, `E' is a 11947 TEMPLATE_DECL with `D<T>' as its DECL_CONTEXT. Now we 11948 have to substitute this with one having context `D<int>'. */ 11949 11950 tree context = tsubst (DECL_CONTEXT (t), args, complain, in_decl); 11951 return lookup_field (context, DECL_NAME(t), 0, false); 11952 } 11953 else 11954 /* Ordinary template template argument. */ 11955 return t; 11956 11957 case CAST_EXPR: 11958 case REINTERPRET_CAST_EXPR: 11959 case CONST_CAST_EXPR: 11960 case STATIC_CAST_EXPR: 11961 case DYNAMIC_CAST_EXPR: 11962 case IMPLICIT_CONV_EXPR: 11963 case CONVERT_EXPR: 11964 case NOP_EXPR: 11965 return build1 11966 (code, tsubst (TREE_TYPE (t), args, complain, in_decl), 11967 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)); 11968 11969 case SIZEOF_EXPR: 11970 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0))) 11971 { 11972 11973 tree expanded; 11974 int len = 0; 11975 11976 ++cp_unevaluated_operand; 11977 ++c_inhibit_evaluation_warnings; 11978 /* We only want to compute the number of arguments. */ 11979 expanded = tsubst_pack_expansion (TREE_OPERAND (t, 0), args, 11980 complain, in_decl); 11981 --cp_unevaluated_operand; 11982 --c_inhibit_evaluation_warnings; 11983 11984 if (TREE_CODE (expanded) == TREE_VEC) 11985 len = TREE_VEC_LENGTH (expanded); 11986 11987 if (expanded == error_mark_node) 11988 return error_mark_node; 11989 else if (PACK_EXPANSION_P (expanded) 11990 || (TREE_CODE (expanded) == TREE_VEC 11991 && len > 0 11992 && PACK_EXPANSION_P (TREE_VEC_ELT (expanded, len-1)))) 11993 { 11994 if (TREE_CODE (expanded) == TREE_VEC) 11995 expanded = TREE_VEC_ELT (expanded, len - 1); 11996 11997 if (TYPE_P (expanded)) 11998 return cxx_sizeof_or_alignof_type (expanded, SIZEOF_EXPR, 11999 complain & tf_error); 12000 else 12001 return cxx_sizeof_or_alignof_expr (expanded, SIZEOF_EXPR, 12002 complain & tf_error); 12003 } 12004 else 12005 return build_int_cst (size_type_node, len); 12006 } 12007 /* Fall through */ 12008 12009 case INDIRECT_REF: 12010 case NEGATE_EXPR: 12011 case TRUTH_NOT_EXPR: 12012 case BIT_NOT_EXPR: 12013 case ADDR_EXPR: 12014 case UNARY_PLUS_EXPR: /* Unary + */ 12015 case ALIGNOF_EXPR: 12016 case AT_ENCODE_EXPR: 12017 case ARROW_EXPR: 12018 case THROW_EXPR: 12019 case TYPEID_EXPR: 12020 case REALPART_EXPR: 12021 case IMAGPART_EXPR: 12022 return build1 12023 (code, tsubst (TREE_TYPE (t), args, complain, in_decl), 12024 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl)); 12025 12026 case COMPONENT_REF: 12027 { 12028 tree object; 12029 tree name; 12030 12031 object = tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl); 12032 name = TREE_OPERAND (t, 1); 12033 if (TREE_CODE (name) == BIT_NOT_EXPR) 12034 { 12035 name = tsubst_copy (TREE_OPERAND (name, 0), args, 12036 complain, in_decl); 12037 name = build1 (BIT_NOT_EXPR, NULL_TREE, name); 12038 } 12039 else if (TREE_CODE (name) == SCOPE_REF 12040 && TREE_CODE (TREE_OPERAND (name, 1)) == BIT_NOT_EXPR) 12041 { 12042 tree base = tsubst_copy (TREE_OPERAND (name, 0), args, 12043 complain, in_decl); 12044 name = TREE_OPERAND (name, 1); 12045 name = tsubst_copy (TREE_OPERAND (name, 0), args, 12046 complain, in_decl); 12047 name = build1 (BIT_NOT_EXPR, NULL_TREE, name); 12048 name = build_qualified_name (/*type=*/NULL_TREE, 12049 base, name, 12050 /*template_p=*/false); 12051 } 12052 else if (BASELINK_P (name)) 12053 name = tsubst_baselink (name, 12054 non_reference (TREE_TYPE (object)), 12055 args, complain, 12056 in_decl); 12057 else 12058 name = tsubst_copy (name, args, complain, in_decl); 12059 return build_nt (COMPONENT_REF, object, name, NULL_TREE); 12060 } 12061 12062 case PLUS_EXPR: 12063 case MINUS_EXPR: 12064 case MULT_EXPR: 12065 case TRUNC_DIV_EXPR: 12066 case CEIL_DIV_EXPR: 12067 case FLOOR_DIV_EXPR: 12068 case ROUND_DIV_EXPR: 12069 case EXACT_DIV_EXPR: 12070 case BIT_AND_EXPR: 12071 case BIT_IOR_EXPR: 12072 case BIT_XOR_EXPR: 12073 case TRUNC_MOD_EXPR: 12074 case FLOOR_MOD_EXPR: 12075 case TRUTH_ANDIF_EXPR: 12076 case TRUTH_ORIF_EXPR: 12077 case TRUTH_AND_EXPR: 12078 case TRUTH_OR_EXPR: 12079 case RSHIFT_EXPR: 12080 case LSHIFT_EXPR: 12081 case RROTATE_EXPR: 12082 case LROTATE_EXPR: 12083 case EQ_EXPR: 12084 case NE_EXPR: 12085 case MAX_EXPR: 12086 case MIN_EXPR: 12087 case LE_EXPR: 12088 case GE_EXPR: 12089 case LT_EXPR: 12090 case GT_EXPR: 12091 case COMPOUND_EXPR: 12092 case DOTSTAR_EXPR: 12093 case MEMBER_REF: 12094 case PREDECREMENT_EXPR: 12095 case PREINCREMENT_EXPR: 12096 case POSTDECREMENT_EXPR: 12097 case POSTINCREMENT_EXPR: 12098 return build_nt 12099 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl), 12100 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl)); 12101 12102 case SCOPE_REF: 12103 return build_qualified_name (/*type=*/NULL_TREE, 12104 tsubst_copy (TREE_OPERAND (t, 0), 12105 args, complain, in_decl), 12106 tsubst_copy (TREE_OPERAND (t, 1), 12107 args, complain, in_decl), 12108 QUALIFIED_NAME_IS_TEMPLATE (t)); 12109 12110 case ARRAY_REF: 12111 return build_nt 12112 (ARRAY_REF, 12113 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl), 12114 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl), 12115 NULL_TREE, NULL_TREE); 12116 12117 case CALL_EXPR: 12118 { 12119 int n = VL_EXP_OPERAND_LENGTH (t); 12120 tree result = build_vl_exp (CALL_EXPR, n); 12121 int i; 12122 for (i = 0; i < n; i++) 12123 TREE_OPERAND (t, i) = tsubst_copy (TREE_OPERAND (t, i), args, 12124 complain, in_decl); 12125 return result; 12126 } 12127 12128 case COND_EXPR: 12129 case MODOP_EXPR: 12130 case PSEUDO_DTOR_EXPR: 12131 { 12132 r = build_nt 12133 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl), 12134 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl), 12135 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl)); 12136 TREE_NO_WARNING (r) = TREE_NO_WARNING (t); 12137 return r; 12138 } 12139 12140 case NEW_EXPR: 12141 { 12142 r = build_nt 12143 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl), 12144 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl), 12145 tsubst_copy (TREE_OPERAND (t, 2), args, complain, in_decl)); 12146 NEW_EXPR_USE_GLOBAL (r) = NEW_EXPR_USE_GLOBAL (t); 12147 return r; 12148 } 12149 12150 case DELETE_EXPR: 12151 { 12152 r = build_nt 12153 (code, tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl), 12154 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl)); 12155 DELETE_EXPR_USE_GLOBAL (r) = DELETE_EXPR_USE_GLOBAL (t); 12156 DELETE_EXPR_USE_VEC (r) = DELETE_EXPR_USE_VEC (t); 12157 return r; 12158 } 12159 12160 case TEMPLATE_ID_EXPR: 12161 { 12162 /* Substituted template arguments */ 12163 tree fn = TREE_OPERAND (t, 0); 12164 tree targs = TREE_OPERAND (t, 1); 12165 12166 fn = tsubst_copy (fn, args, complain, in_decl); 12167 if (targs) 12168 targs = tsubst_template_args (targs, args, complain, in_decl); 12169 12170 return lookup_template_function (fn, targs); 12171 } 12172 12173 case TREE_LIST: 12174 { 12175 tree purpose, value, chain; 12176 12177 if (t == void_list_node) 12178 return t; 12179 12180 purpose = TREE_PURPOSE (t); 12181 if (purpose) 12182 purpose = tsubst_copy (purpose, args, complain, in_decl); 12183 value = TREE_VALUE (t); 12184 if (value) 12185 value = tsubst_copy (value, args, complain, in_decl); 12186 chain = TREE_CHAIN (t); 12187 if (chain && chain != void_type_node) 12188 chain = tsubst_copy (chain, args, complain, in_decl); 12189 if (purpose == TREE_PURPOSE (t) 12190 && value == TREE_VALUE (t) 12191 && chain == TREE_CHAIN (t)) 12192 return t; 12193 return tree_cons (purpose, value, chain); 12194 } 12195 12196 case RECORD_TYPE: 12197 case UNION_TYPE: 12198 case ENUMERAL_TYPE: 12199 case INTEGER_TYPE: 12200 case TEMPLATE_TYPE_PARM: 12201 case TEMPLATE_TEMPLATE_PARM: 12202 case BOUND_TEMPLATE_TEMPLATE_PARM: 12203 case TEMPLATE_PARM_INDEX: 12204 case POINTER_TYPE: 12205 case REFERENCE_TYPE: 12206 case OFFSET_TYPE: 12207 case FUNCTION_TYPE: 12208 case METHOD_TYPE: 12209 case ARRAY_TYPE: 12210 case TYPENAME_TYPE: 12211 case UNBOUND_CLASS_TEMPLATE: 12212 case TYPEOF_TYPE: 12213 case DECLTYPE_TYPE: 12214 case TYPE_DECL: 12215 return tsubst (t, args, complain, in_decl); 12216 12217 case IDENTIFIER_NODE: 12218 if (IDENTIFIER_TYPENAME_P (t)) 12219 { 12220 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl); 12221 return mangle_conv_op_name_for_type (new_type); 12222 } 12223 else 12224 return t; 12225 12226 case CONSTRUCTOR: 12227 /* This is handled by tsubst_copy_and_build. */ 12228 gcc_unreachable (); 12229 12230 case VA_ARG_EXPR: 12231 return build_x_va_arg (tsubst_copy (TREE_OPERAND (t, 0), args, complain, 12232 in_decl), 12233 tsubst (TREE_TYPE (t), args, complain, in_decl)); 12234 12235 case CLEANUP_POINT_EXPR: 12236 /* We shouldn't have built any of these during initial template 12237 generation. Instead, they should be built during instantiation 12238 in response to the saved STMT_IS_FULL_EXPR_P setting. */ 12239 gcc_unreachable (); 12240 12241 case OFFSET_REF: 12242 r = build2 12243 (code, tsubst (TREE_TYPE (t), args, complain, in_decl), 12244 tsubst_copy (TREE_OPERAND (t, 0), args, complain, in_decl), 12245 tsubst_copy (TREE_OPERAND (t, 1), args, complain, in_decl)); 12246 PTRMEM_OK_P (r) = PTRMEM_OK_P (t); 12247 mark_used (TREE_OPERAND (r, 1)); 12248 return r; 12249 12250 case EXPR_PACK_EXPANSION: 12251 error ("invalid use of pack expansion expression"); 12252 return error_mark_node; 12253 12254 case NONTYPE_ARGUMENT_PACK: 12255 error ("use %<...%> to expand argument pack"); 12256 return error_mark_node; 12257 12258 case INTEGER_CST: 12259 case REAL_CST: 12260 case STRING_CST: 12261 case COMPLEX_CST: 12262 { 12263 /* Instantiate any typedefs in the type. */ 12264 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); 12265 r = fold_convert (type, t); 12266 gcc_assert (TREE_CODE (r) == code); 12267 return r; 12268 } 12269 12270 case PTRMEM_CST: 12271 /* These can sometimes show up in a partial instantiation, but never 12272 involve template parms. */ 12273 gcc_assert (!uses_template_parms (t)); 12274 return t; 12275 12276 default: 12277 /* We shouldn't get here, but keep going if !ENABLE_CHECKING. */ 12278 gcc_checking_assert (false); 12279 return t; 12280 } 12281 } 12282 12283 /* Like tsubst_copy, but specifically for OpenMP clauses. */ 12284 12285 static tree 12286 tsubst_omp_clauses (tree clauses, tree args, tsubst_flags_t complain, 12287 tree in_decl) 12288 { 12289 tree new_clauses = NULL, nc, oc; 12290 12291 for (oc = clauses; oc ; oc = OMP_CLAUSE_CHAIN (oc)) 12292 { 12293 nc = copy_node (oc); 12294 OMP_CLAUSE_CHAIN (nc) = new_clauses; 12295 new_clauses = nc; 12296 12297 switch (OMP_CLAUSE_CODE (nc)) 12298 { 12299 case OMP_CLAUSE_LASTPRIVATE: 12300 if (OMP_CLAUSE_LASTPRIVATE_STMT (oc)) 12301 { 12302 OMP_CLAUSE_LASTPRIVATE_STMT (nc) = push_stmt_list (); 12303 tsubst_expr (OMP_CLAUSE_LASTPRIVATE_STMT (oc), args, complain, 12304 in_decl, /*integral_constant_expression_p=*/false); 12305 OMP_CLAUSE_LASTPRIVATE_STMT (nc) 12306 = pop_stmt_list (OMP_CLAUSE_LASTPRIVATE_STMT (nc)); 12307 } 12308 /* FALLTHRU */ 12309 case OMP_CLAUSE_PRIVATE: 12310 case OMP_CLAUSE_SHARED: 12311 case OMP_CLAUSE_FIRSTPRIVATE: 12312 case OMP_CLAUSE_REDUCTION: 12313 case OMP_CLAUSE_COPYIN: 12314 case OMP_CLAUSE_COPYPRIVATE: 12315 case OMP_CLAUSE_IF: 12316 case OMP_CLAUSE_NUM_THREADS: 12317 case OMP_CLAUSE_SCHEDULE: 12318 case OMP_CLAUSE_COLLAPSE: 12319 case OMP_CLAUSE_FINAL: 12320 OMP_CLAUSE_OPERAND (nc, 0) 12321 = tsubst_expr (OMP_CLAUSE_OPERAND (oc, 0), args, complain, 12322 in_decl, /*integral_constant_expression_p=*/false); 12323 break; 12324 case OMP_CLAUSE_NOWAIT: 12325 case OMP_CLAUSE_ORDERED: 12326 case OMP_CLAUSE_DEFAULT: 12327 case OMP_CLAUSE_UNTIED: 12328 case OMP_CLAUSE_MERGEABLE: 12329 break; 12330 default: 12331 gcc_unreachable (); 12332 } 12333 } 12334 12335 return finish_omp_clauses (nreverse (new_clauses)); 12336 } 12337 12338 /* Like tsubst_copy_and_build, but unshare TREE_LIST nodes. */ 12339 12340 static tree 12341 tsubst_copy_asm_operands (tree t, tree args, tsubst_flags_t complain, 12342 tree in_decl) 12343 { 12344 #define RECUR(t) tsubst_copy_asm_operands (t, args, complain, in_decl) 12345 12346 tree purpose, value, chain; 12347 12348 if (t == NULL) 12349 return t; 12350 12351 if (TREE_CODE (t) != TREE_LIST) 12352 return tsubst_copy_and_build (t, args, complain, in_decl, 12353 /*function_p=*/false, 12354 /*integral_constant_expression_p=*/false); 12355 12356 if (t == void_list_node) 12357 return t; 12358 12359 purpose = TREE_PURPOSE (t); 12360 if (purpose) 12361 purpose = RECUR (purpose); 12362 value = TREE_VALUE (t); 12363 if (value) 12364 { 12365 if (TREE_CODE (value) != LABEL_DECL) 12366 value = RECUR (value); 12367 else 12368 { 12369 value = lookup_label (DECL_NAME (value)); 12370 gcc_assert (TREE_CODE (value) == LABEL_DECL); 12371 TREE_USED (value) = 1; 12372 } 12373 } 12374 chain = TREE_CHAIN (t); 12375 if (chain && chain != void_type_node) 12376 chain = RECUR (chain); 12377 return tree_cons (purpose, value, chain); 12378 #undef RECUR 12379 } 12380 12381 /* Substitute one OMP_FOR iterator. */ 12382 12383 static void 12384 tsubst_omp_for_iterator (tree t, int i, tree declv, tree initv, 12385 tree condv, tree incrv, tree *clauses, 12386 tree args, tsubst_flags_t complain, tree in_decl, 12387 bool integral_constant_expression_p) 12388 { 12389 #define RECUR(NODE) \ 12390 tsubst_expr ((NODE), args, complain, in_decl, \ 12391 integral_constant_expression_p) 12392 tree decl, init, cond, incr, auto_node; 12393 12394 init = TREE_VEC_ELT (OMP_FOR_INIT (t), i); 12395 gcc_assert (TREE_CODE (init) == MODIFY_EXPR); 12396 decl = RECUR (TREE_OPERAND (init, 0)); 12397 init = TREE_OPERAND (init, 1); 12398 auto_node = type_uses_auto (TREE_TYPE (decl)); 12399 if (auto_node && init) 12400 { 12401 tree init_expr = init; 12402 if (TREE_CODE (init_expr) == DECL_EXPR) 12403 init_expr = DECL_INITIAL (DECL_EXPR_DECL (init_expr)); 12404 init_expr = RECUR (init_expr); 12405 TREE_TYPE (decl) 12406 = do_auto_deduction (TREE_TYPE (decl), init_expr, auto_node); 12407 } 12408 gcc_assert (!type_dependent_expression_p (decl)); 12409 12410 if (!CLASS_TYPE_P (TREE_TYPE (decl))) 12411 { 12412 cond = RECUR (TREE_VEC_ELT (OMP_FOR_COND (t), i)); 12413 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i); 12414 if (TREE_CODE (incr) == MODIFY_EXPR) 12415 incr = build_x_modify_expr (RECUR (TREE_OPERAND (incr, 0)), NOP_EXPR, 12416 RECUR (TREE_OPERAND (incr, 1)), 12417 complain); 12418 else 12419 incr = RECUR (incr); 12420 TREE_VEC_ELT (declv, i) = decl; 12421 TREE_VEC_ELT (initv, i) = init; 12422 TREE_VEC_ELT (condv, i) = cond; 12423 TREE_VEC_ELT (incrv, i) = incr; 12424 return; 12425 } 12426 12427 if (init && TREE_CODE (init) != DECL_EXPR) 12428 { 12429 tree c; 12430 for (c = *clauses; c ; c = OMP_CLAUSE_CHAIN (c)) 12431 { 12432 if ((OMP_CLAUSE_CODE (c) == OMP_CLAUSE_PRIVATE 12433 || OMP_CLAUSE_CODE (c) == OMP_CLAUSE_LASTPRIVATE) 12434 && OMP_CLAUSE_DECL (c) == decl) 12435 break; 12436 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_FIRSTPRIVATE 12437 && OMP_CLAUSE_DECL (c) == decl) 12438 error ("iteration variable %qD should not be firstprivate", decl); 12439 else if (OMP_CLAUSE_CODE (c) == OMP_CLAUSE_REDUCTION 12440 && OMP_CLAUSE_DECL (c) == decl) 12441 error ("iteration variable %qD should not be reduction", decl); 12442 } 12443 if (c == NULL) 12444 { 12445 c = build_omp_clause (input_location, OMP_CLAUSE_PRIVATE); 12446 OMP_CLAUSE_DECL (c) = decl; 12447 c = finish_omp_clauses (c); 12448 if (c) 12449 { 12450 OMP_CLAUSE_CHAIN (c) = *clauses; 12451 *clauses = c; 12452 } 12453 } 12454 } 12455 cond = TREE_VEC_ELT (OMP_FOR_COND (t), i); 12456 if (COMPARISON_CLASS_P (cond)) 12457 cond = build2 (TREE_CODE (cond), boolean_type_node, 12458 RECUR (TREE_OPERAND (cond, 0)), 12459 RECUR (TREE_OPERAND (cond, 1))); 12460 else 12461 cond = RECUR (cond); 12462 incr = TREE_VEC_ELT (OMP_FOR_INCR (t), i); 12463 switch (TREE_CODE (incr)) 12464 { 12465 case PREINCREMENT_EXPR: 12466 case PREDECREMENT_EXPR: 12467 case POSTINCREMENT_EXPR: 12468 case POSTDECREMENT_EXPR: 12469 incr = build2 (TREE_CODE (incr), TREE_TYPE (decl), 12470 RECUR (TREE_OPERAND (incr, 0)), NULL_TREE); 12471 break; 12472 case MODIFY_EXPR: 12473 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR 12474 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR) 12475 { 12476 tree rhs = TREE_OPERAND (incr, 1); 12477 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), 12478 RECUR (TREE_OPERAND (incr, 0)), 12479 build2 (TREE_CODE (rhs), TREE_TYPE (decl), 12480 RECUR (TREE_OPERAND (rhs, 0)), 12481 RECUR (TREE_OPERAND (rhs, 1)))); 12482 } 12483 else 12484 incr = RECUR (incr); 12485 break; 12486 case MODOP_EXPR: 12487 if (TREE_CODE (TREE_OPERAND (incr, 1)) == PLUS_EXPR 12488 || TREE_CODE (TREE_OPERAND (incr, 1)) == MINUS_EXPR) 12489 { 12490 tree lhs = RECUR (TREE_OPERAND (incr, 0)); 12491 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), lhs, 12492 build2 (TREE_CODE (TREE_OPERAND (incr, 1)), 12493 TREE_TYPE (decl), lhs, 12494 RECUR (TREE_OPERAND (incr, 2)))); 12495 } 12496 else if (TREE_CODE (TREE_OPERAND (incr, 1)) == NOP_EXPR 12497 && (TREE_CODE (TREE_OPERAND (incr, 2)) == PLUS_EXPR 12498 || (TREE_CODE (TREE_OPERAND (incr, 2)) == MINUS_EXPR))) 12499 { 12500 tree rhs = TREE_OPERAND (incr, 2); 12501 incr = build2 (MODIFY_EXPR, TREE_TYPE (decl), 12502 RECUR (TREE_OPERAND (incr, 0)), 12503 build2 (TREE_CODE (rhs), TREE_TYPE (decl), 12504 RECUR (TREE_OPERAND (rhs, 0)), 12505 RECUR (TREE_OPERAND (rhs, 1)))); 12506 } 12507 else 12508 incr = RECUR (incr); 12509 break; 12510 default: 12511 incr = RECUR (incr); 12512 break; 12513 } 12514 12515 TREE_VEC_ELT (declv, i) = decl; 12516 TREE_VEC_ELT (initv, i) = init; 12517 TREE_VEC_ELT (condv, i) = cond; 12518 TREE_VEC_ELT (incrv, i) = incr; 12519 #undef RECUR 12520 } 12521 12522 /* Like tsubst_copy for expressions, etc. but also does semantic 12523 processing. */ 12524 12525 static tree 12526 tsubst_expr (tree t, tree args, tsubst_flags_t complain, tree in_decl, 12527 bool integral_constant_expression_p) 12528 { 12529 #define RECUR(NODE) \ 12530 tsubst_expr ((NODE), args, complain, in_decl, \ 12531 integral_constant_expression_p) 12532 12533 tree stmt, tmp; 12534 12535 if (t == NULL_TREE || t == error_mark_node) 12536 return t; 12537 12538 if (EXPR_HAS_LOCATION (t)) 12539 input_location = EXPR_LOCATION (t); 12540 if (STATEMENT_CODE_P (TREE_CODE (t))) 12541 current_stmt_tree ()->stmts_are_full_exprs_p = STMT_IS_FULL_EXPR_P (t); 12542 12543 switch (TREE_CODE (t)) 12544 { 12545 case STATEMENT_LIST: 12546 { 12547 tree_stmt_iterator i; 12548 for (i = tsi_start (t); !tsi_end_p (i); tsi_next (&i)) 12549 RECUR (tsi_stmt (i)); 12550 break; 12551 } 12552 12553 case CTOR_INITIALIZER: 12554 finish_mem_initializers (tsubst_initializer_list 12555 (TREE_OPERAND (t, 0), args)); 12556 break; 12557 12558 case RETURN_EXPR: 12559 finish_return_stmt (RECUR (TREE_OPERAND (t, 0))); 12560 break; 12561 12562 case EXPR_STMT: 12563 tmp = RECUR (EXPR_STMT_EXPR (t)); 12564 if (EXPR_STMT_STMT_EXPR_RESULT (t)) 12565 finish_stmt_expr_expr (tmp, cur_stmt_expr); 12566 else 12567 finish_expr_stmt (tmp); 12568 break; 12569 12570 case USING_STMT: 12571 do_using_directive (USING_STMT_NAMESPACE (t)); 12572 break; 12573 12574 case DECL_EXPR: 12575 { 12576 tree decl, pattern_decl; 12577 tree init; 12578 12579 pattern_decl = decl = DECL_EXPR_DECL (t); 12580 if (TREE_CODE (decl) == LABEL_DECL) 12581 finish_label_decl (DECL_NAME (decl)); 12582 else if (TREE_CODE (decl) == USING_DECL) 12583 { 12584 tree scope = USING_DECL_SCOPE (decl); 12585 tree name = DECL_NAME (decl); 12586 tree decl; 12587 12588 scope = tsubst (scope, args, complain, in_decl); 12589 decl = lookup_qualified_name (scope, name, 12590 /*is_type_p=*/false, 12591 /*complain=*/false); 12592 if (decl == error_mark_node || TREE_CODE (decl) == TREE_LIST) 12593 qualified_name_lookup_error (scope, name, decl, input_location); 12594 else 12595 do_local_using_decl (decl, scope, name); 12596 } 12597 else 12598 { 12599 init = DECL_INITIAL (decl); 12600 decl = tsubst (decl, args, complain, in_decl); 12601 if (decl != error_mark_node) 12602 { 12603 /* By marking the declaration as instantiated, we avoid 12604 trying to instantiate it. Since instantiate_decl can't 12605 handle local variables, and since we've already done 12606 all that needs to be done, that's the right thing to 12607 do. */ 12608 if (TREE_CODE (decl) == VAR_DECL) 12609 DECL_TEMPLATE_INSTANTIATED (decl) = 1; 12610 if (TREE_CODE (decl) == VAR_DECL 12611 && ANON_AGGR_TYPE_P (TREE_TYPE (decl))) 12612 /* Anonymous aggregates are a special case. */ 12613 finish_anon_union (decl); 12614 else if (is_capture_proxy (DECL_EXPR_DECL (t))) 12615 { 12616 DECL_CONTEXT (decl) = current_function_decl; 12617 if (DECL_NAME (decl) == this_identifier) 12618 { 12619 tree lam = DECL_CONTEXT (current_function_decl); 12620 lam = CLASSTYPE_LAMBDA_EXPR (lam); 12621 LAMBDA_EXPR_THIS_CAPTURE (lam) = decl; 12622 } 12623 insert_capture_proxy (decl); 12624 } 12625 else 12626 { 12627 int const_init = false; 12628 maybe_push_decl (decl); 12629 if (TREE_CODE (decl) == VAR_DECL 12630 && DECL_PRETTY_FUNCTION_P (decl)) 12631 { 12632 /* For __PRETTY_FUNCTION__ we have to adjust the 12633 initializer. */ 12634 const char *const name 12635 = cxx_printable_name (current_function_decl, 2); 12636 init = cp_fname_init (name, &TREE_TYPE (decl)); 12637 } 12638 else 12639 { 12640 tree t = RECUR (init); 12641 12642 if (init && !t) 12643 { 12644 /* If we had an initializer but it 12645 instantiated to nothing, 12646 value-initialize the object. This will 12647 only occur when the initializer was a 12648 pack expansion where the parameter packs 12649 used in that expansion were of length 12650 zero. */ 12651 init = build_value_init (TREE_TYPE (decl), 12652 complain); 12653 if (TREE_CODE (init) == AGGR_INIT_EXPR) 12654 init = get_target_expr_sfinae (init, complain); 12655 } 12656 else 12657 init = t; 12658 } 12659 12660 if (TREE_CODE (decl) == VAR_DECL) 12661 const_init = (DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P 12662 (pattern_decl)); 12663 cp_finish_decl (decl, init, const_init, NULL_TREE, 0); 12664 } 12665 } 12666 } 12667 12668 /* A DECL_EXPR can also be used as an expression, in the condition 12669 clause of an if/for/while construct. */ 12670 return decl; 12671 } 12672 12673 case FOR_STMT: 12674 stmt = begin_for_stmt (NULL_TREE, NULL_TREE); 12675 RECUR (FOR_INIT_STMT (t)); 12676 finish_for_init_stmt (stmt); 12677 tmp = RECUR (FOR_COND (t)); 12678 finish_for_cond (tmp, stmt); 12679 tmp = RECUR (FOR_EXPR (t)); 12680 finish_for_expr (tmp, stmt); 12681 RECUR (FOR_BODY (t)); 12682 finish_for_stmt (stmt); 12683 break; 12684 12685 case RANGE_FOR_STMT: 12686 { 12687 tree decl, expr; 12688 stmt = begin_for_stmt (NULL_TREE, NULL_TREE); 12689 decl = RANGE_FOR_DECL (t); 12690 decl = tsubst (decl, args, complain, in_decl); 12691 maybe_push_decl (decl); 12692 expr = RECUR (RANGE_FOR_EXPR (t)); 12693 stmt = cp_convert_range_for (stmt, decl, expr); 12694 RECUR (RANGE_FOR_BODY (t)); 12695 finish_for_stmt (stmt); 12696 } 12697 break; 12698 12699 case WHILE_STMT: 12700 stmt = begin_while_stmt (); 12701 tmp = RECUR (WHILE_COND (t)); 12702 finish_while_stmt_cond (tmp, stmt); 12703 RECUR (WHILE_BODY (t)); 12704 finish_while_stmt (stmt); 12705 break; 12706 12707 case DO_STMT: 12708 stmt = begin_do_stmt (); 12709 RECUR (DO_BODY (t)); 12710 finish_do_body (stmt); 12711 tmp = RECUR (DO_COND (t)); 12712 finish_do_stmt (tmp, stmt); 12713 break; 12714 12715 case IF_STMT: 12716 stmt = begin_if_stmt (); 12717 tmp = RECUR (IF_COND (t)); 12718 finish_if_stmt_cond (tmp, stmt); 12719 RECUR (THEN_CLAUSE (t)); 12720 finish_then_clause (stmt); 12721 12722 if (ELSE_CLAUSE (t)) 12723 { 12724 begin_else_clause (stmt); 12725 RECUR (ELSE_CLAUSE (t)); 12726 finish_else_clause (stmt); 12727 } 12728 12729 finish_if_stmt (stmt); 12730 break; 12731 12732 case BIND_EXPR: 12733 if (BIND_EXPR_BODY_BLOCK (t)) 12734 stmt = begin_function_body (); 12735 else 12736 stmt = begin_compound_stmt (BIND_EXPR_TRY_BLOCK (t) 12737 ? BCS_TRY_BLOCK : 0); 12738 12739 RECUR (BIND_EXPR_BODY (t)); 12740 12741 if (BIND_EXPR_BODY_BLOCK (t)) 12742 finish_function_body (stmt); 12743 else 12744 finish_compound_stmt (stmt); 12745 break; 12746 12747 case BREAK_STMT: 12748 finish_break_stmt (); 12749 break; 12750 12751 case CONTINUE_STMT: 12752 finish_continue_stmt (); 12753 break; 12754 12755 case SWITCH_STMT: 12756 stmt = begin_switch_stmt (); 12757 tmp = RECUR (SWITCH_STMT_COND (t)); 12758 finish_switch_cond (tmp, stmt); 12759 RECUR (SWITCH_STMT_BODY (t)); 12760 finish_switch_stmt (stmt); 12761 break; 12762 12763 case CASE_LABEL_EXPR: 12764 finish_case_label (EXPR_LOCATION (t), 12765 RECUR (CASE_LOW (t)), 12766 RECUR (CASE_HIGH (t))); 12767 break; 12768 12769 case LABEL_EXPR: 12770 { 12771 tree decl = LABEL_EXPR_LABEL (t); 12772 tree label; 12773 12774 label = finish_label_stmt (DECL_NAME (decl)); 12775 if (DECL_ATTRIBUTES (decl) != NULL_TREE) 12776 cplus_decl_attributes (&label, DECL_ATTRIBUTES (decl), 0); 12777 } 12778 break; 12779 12780 case GOTO_EXPR: 12781 tmp = GOTO_DESTINATION (t); 12782 if (TREE_CODE (tmp) != LABEL_DECL) 12783 /* Computed goto's must be tsubst'd into. On the other hand, 12784 non-computed gotos must not be; the identifier in question 12785 will have no binding. */ 12786 tmp = RECUR (tmp); 12787 else 12788 tmp = DECL_NAME (tmp); 12789 finish_goto_stmt (tmp); 12790 break; 12791 12792 case ASM_EXPR: 12793 tmp = finish_asm_stmt 12794 (ASM_VOLATILE_P (t), 12795 RECUR (ASM_STRING (t)), 12796 tsubst_copy_asm_operands (ASM_OUTPUTS (t), args, complain, in_decl), 12797 tsubst_copy_asm_operands (ASM_INPUTS (t), args, complain, in_decl), 12798 tsubst_copy_asm_operands (ASM_CLOBBERS (t), args, complain, in_decl), 12799 tsubst_copy_asm_operands (ASM_LABELS (t), args, complain, in_decl)); 12800 { 12801 tree asm_expr = tmp; 12802 if (TREE_CODE (asm_expr) == CLEANUP_POINT_EXPR) 12803 asm_expr = TREE_OPERAND (asm_expr, 0); 12804 ASM_INPUT_P (asm_expr) = ASM_INPUT_P (t); 12805 } 12806 break; 12807 12808 case TRY_BLOCK: 12809 if (CLEANUP_P (t)) 12810 { 12811 stmt = begin_try_block (); 12812 RECUR (TRY_STMTS (t)); 12813 finish_cleanup_try_block (stmt); 12814 finish_cleanup (RECUR (TRY_HANDLERS (t)), stmt); 12815 } 12816 else 12817 { 12818 tree compound_stmt = NULL_TREE; 12819 12820 if (FN_TRY_BLOCK_P (t)) 12821 stmt = begin_function_try_block (&compound_stmt); 12822 else 12823 stmt = begin_try_block (); 12824 12825 RECUR (TRY_STMTS (t)); 12826 12827 if (FN_TRY_BLOCK_P (t)) 12828 finish_function_try_block (stmt); 12829 else 12830 finish_try_block (stmt); 12831 12832 RECUR (TRY_HANDLERS (t)); 12833 if (FN_TRY_BLOCK_P (t)) 12834 finish_function_handler_sequence (stmt, compound_stmt); 12835 else 12836 finish_handler_sequence (stmt); 12837 } 12838 break; 12839 12840 case HANDLER: 12841 { 12842 tree decl = HANDLER_PARMS (t); 12843 12844 if (decl) 12845 { 12846 decl = tsubst (decl, args, complain, in_decl); 12847 /* Prevent instantiate_decl from trying to instantiate 12848 this variable. We've already done all that needs to be 12849 done. */ 12850 if (decl != error_mark_node) 12851 DECL_TEMPLATE_INSTANTIATED (decl) = 1; 12852 } 12853 stmt = begin_handler (); 12854 finish_handler_parms (decl, stmt); 12855 RECUR (HANDLER_BODY (t)); 12856 finish_handler (stmt); 12857 } 12858 break; 12859 12860 case TAG_DEFN: 12861 tsubst (TREE_TYPE (t), args, complain, NULL_TREE); 12862 break; 12863 12864 case STATIC_ASSERT: 12865 { 12866 tree condition = 12867 tsubst_expr (STATIC_ASSERT_CONDITION (t), 12868 args, 12869 complain, in_decl, 12870 /*integral_constant_expression_p=*/true); 12871 finish_static_assert (condition, 12872 STATIC_ASSERT_MESSAGE (t), 12873 STATIC_ASSERT_SOURCE_LOCATION (t), 12874 /*member_p=*/false); 12875 } 12876 break; 12877 12878 case OMP_PARALLEL: 12879 tmp = tsubst_omp_clauses (OMP_PARALLEL_CLAUSES (t), 12880 args, complain, in_decl); 12881 stmt = begin_omp_parallel (); 12882 RECUR (OMP_PARALLEL_BODY (t)); 12883 OMP_PARALLEL_COMBINED (finish_omp_parallel (tmp, stmt)) 12884 = OMP_PARALLEL_COMBINED (t); 12885 break; 12886 12887 case OMP_TASK: 12888 tmp = tsubst_omp_clauses (OMP_TASK_CLAUSES (t), 12889 args, complain, in_decl); 12890 stmt = begin_omp_task (); 12891 RECUR (OMP_TASK_BODY (t)); 12892 finish_omp_task (tmp, stmt); 12893 break; 12894 12895 case OMP_FOR: 12896 { 12897 tree clauses, body, pre_body; 12898 tree declv, initv, condv, incrv; 12899 int i; 12900 12901 clauses = tsubst_omp_clauses (OMP_FOR_CLAUSES (t), 12902 args, complain, in_decl); 12903 declv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t))); 12904 initv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t))); 12905 condv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t))); 12906 incrv = make_tree_vec (TREE_VEC_LENGTH (OMP_FOR_INIT (t))); 12907 12908 for (i = 0; i < TREE_VEC_LENGTH (OMP_FOR_INIT (t)); i++) 12909 tsubst_omp_for_iterator (t, i, declv, initv, condv, incrv, 12910 &clauses, args, complain, in_decl, 12911 integral_constant_expression_p); 12912 12913 stmt = begin_omp_structured_block (); 12914 12915 for (i = 0; i < TREE_VEC_LENGTH (initv); i++) 12916 if (TREE_VEC_ELT (initv, i) == NULL 12917 || TREE_CODE (TREE_VEC_ELT (initv, i)) != DECL_EXPR) 12918 TREE_VEC_ELT (initv, i) = RECUR (TREE_VEC_ELT (initv, i)); 12919 else if (CLASS_TYPE_P (TREE_TYPE (TREE_VEC_ELT (initv, i)))) 12920 { 12921 tree init = RECUR (TREE_VEC_ELT (initv, i)); 12922 gcc_assert (init == TREE_VEC_ELT (declv, i)); 12923 TREE_VEC_ELT (initv, i) = NULL_TREE; 12924 } 12925 else 12926 { 12927 tree decl_expr = TREE_VEC_ELT (initv, i); 12928 tree init = DECL_INITIAL (DECL_EXPR_DECL (decl_expr)); 12929 gcc_assert (init != NULL); 12930 TREE_VEC_ELT (initv, i) = RECUR (init); 12931 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = NULL; 12932 RECUR (decl_expr); 12933 DECL_INITIAL (DECL_EXPR_DECL (decl_expr)) = init; 12934 } 12935 12936 pre_body = push_stmt_list (); 12937 RECUR (OMP_FOR_PRE_BODY (t)); 12938 pre_body = pop_stmt_list (pre_body); 12939 12940 body = push_stmt_list (); 12941 RECUR (OMP_FOR_BODY (t)); 12942 body = pop_stmt_list (body); 12943 12944 t = finish_omp_for (EXPR_LOCATION (t), declv, initv, condv, incrv, 12945 body, pre_body, clauses); 12946 12947 add_stmt (finish_omp_structured_block (stmt)); 12948 } 12949 break; 12950 12951 case OMP_SECTIONS: 12952 case OMP_SINGLE: 12953 tmp = tsubst_omp_clauses (OMP_CLAUSES (t), args, complain, in_decl); 12954 stmt = push_stmt_list (); 12955 RECUR (OMP_BODY (t)); 12956 stmt = pop_stmt_list (stmt); 12957 12958 t = copy_node (t); 12959 OMP_BODY (t) = stmt; 12960 OMP_CLAUSES (t) = tmp; 12961 add_stmt (t); 12962 break; 12963 12964 case OMP_SECTION: 12965 case OMP_CRITICAL: 12966 case OMP_MASTER: 12967 case OMP_ORDERED: 12968 stmt = push_stmt_list (); 12969 RECUR (OMP_BODY (t)); 12970 stmt = pop_stmt_list (stmt); 12971 12972 t = copy_node (t); 12973 OMP_BODY (t) = stmt; 12974 add_stmt (t); 12975 break; 12976 12977 case OMP_ATOMIC: 12978 gcc_assert (OMP_ATOMIC_DEPENDENT_P (t)); 12979 if (TREE_CODE (TREE_OPERAND (t, 1)) != MODIFY_EXPR) 12980 { 12981 tree op1 = TREE_OPERAND (t, 1); 12982 tree rhs1 = NULL_TREE; 12983 tree lhs, rhs; 12984 if (TREE_CODE (op1) == COMPOUND_EXPR) 12985 { 12986 rhs1 = RECUR (TREE_OPERAND (op1, 0)); 12987 op1 = TREE_OPERAND (op1, 1); 12988 } 12989 lhs = RECUR (TREE_OPERAND (op1, 0)); 12990 rhs = RECUR (TREE_OPERAND (op1, 1)); 12991 finish_omp_atomic (OMP_ATOMIC, TREE_CODE (op1), lhs, rhs, 12992 NULL_TREE, NULL_TREE, rhs1); 12993 } 12994 else 12995 { 12996 tree op1 = TREE_OPERAND (t, 1); 12997 tree v = NULL_TREE, lhs, rhs = NULL_TREE, lhs1 = NULL_TREE; 12998 tree rhs1 = NULL_TREE; 12999 enum tree_code code = TREE_CODE (TREE_OPERAND (op1, 1)); 13000 enum tree_code opcode = NOP_EXPR; 13001 if (code == OMP_ATOMIC_READ) 13002 { 13003 v = RECUR (TREE_OPERAND (op1, 0)); 13004 lhs = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0)); 13005 } 13006 else if (code == OMP_ATOMIC_CAPTURE_OLD 13007 || code == OMP_ATOMIC_CAPTURE_NEW) 13008 { 13009 tree op11 = TREE_OPERAND (TREE_OPERAND (op1, 1), 1); 13010 v = RECUR (TREE_OPERAND (op1, 0)); 13011 lhs1 = RECUR (TREE_OPERAND (TREE_OPERAND (op1, 1), 0)); 13012 if (TREE_CODE (op11) == COMPOUND_EXPR) 13013 { 13014 rhs1 = RECUR (TREE_OPERAND (op11, 0)); 13015 op11 = TREE_OPERAND (op11, 1); 13016 } 13017 lhs = RECUR (TREE_OPERAND (op11, 0)); 13018 rhs = RECUR (TREE_OPERAND (op11, 1)); 13019 opcode = TREE_CODE (op11); 13020 } 13021 else 13022 { 13023 code = OMP_ATOMIC; 13024 lhs = RECUR (TREE_OPERAND (op1, 0)); 13025 rhs = RECUR (TREE_OPERAND (op1, 1)); 13026 } 13027 finish_omp_atomic (code, opcode, lhs, rhs, v, lhs1, rhs1); 13028 } 13029 break; 13030 13031 case TRANSACTION_EXPR: 13032 { 13033 int flags = 0; 13034 flags |= (TRANSACTION_EXPR_OUTER (t) ? TM_STMT_ATTR_OUTER : 0); 13035 flags |= (TRANSACTION_EXPR_RELAXED (t) ? TM_STMT_ATTR_RELAXED : 0); 13036 13037 if (TRANSACTION_EXPR_IS_STMT (t)) 13038 { 13039 tree body = TRANSACTION_EXPR_BODY (t); 13040 tree noex = NULL_TREE; 13041 if (TREE_CODE (body) == MUST_NOT_THROW_EXPR) 13042 { 13043 noex = MUST_NOT_THROW_COND (body); 13044 if (noex == NULL_TREE) 13045 noex = boolean_true_node; 13046 body = TREE_OPERAND (body, 0); 13047 } 13048 stmt = begin_transaction_stmt (input_location, NULL, flags); 13049 RECUR (body); 13050 finish_transaction_stmt (stmt, NULL, flags, RECUR (noex)); 13051 } 13052 else 13053 { 13054 stmt = build_transaction_expr (EXPR_LOCATION (t), 13055 RECUR (TRANSACTION_EXPR_BODY (t)), 13056 flags, NULL_TREE); 13057 return stmt; 13058 } 13059 } 13060 break; 13061 13062 case MUST_NOT_THROW_EXPR: 13063 return build_must_not_throw_expr (RECUR (TREE_OPERAND (t, 0)), 13064 RECUR (MUST_NOT_THROW_COND (t))); 13065 13066 case EXPR_PACK_EXPANSION: 13067 error ("invalid use of pack expansion expression"); 13068 return error_mark_node; 13069 13070 case NONTYPE_ARGUMENT_PACK: 13071 error ("use %<...%> to expand argument pack"); 13072 return error_mark_node; 13073 13074 default: 13075 gcc_assert (!STATEMENT_CODE_P (TREE_CODE (t))); 13076 13077 return tsubst_copy_and_build (t, args, complain, in_decl, 13078 /*function_p=*/false, 13079 integral_constant_expression_p); 13080 } 13081 13082 return NULL_TREE; 13083 #undef RECUR 13084 } 13085 13086 /* T is a postfix-expression that is not being used in a function 13087 call. Return the substituted version of T. */ 13088 13089 static tree 13090 tsubst_non_call_postfix_expression (tree t, tree args, 13091 tsubst_flags_t complain, 13092 tree in_decl) 13093 { 13094 if (TREE_CODE (t) == SCOPE_REF) 13095 t = tsubst_qualified_id (t, args, complain, in_decl, 13096 /*done=*/false, /*address_p=*/false); 13097 else 13098 t = tsubst_copy_and_build (t, args, complain, in_decl, 13099 /*function_p=*/false, 13100 /*integral_constant_expression_p=*/false); 13101 13102 return t; 13103 } 13104 13105 /* Like tsubst but deals with expressions and performs semantic 13106 analysis. FUNCTION_P is true if T is the "F" in "F (ARGS)". */ 13107 13108 tree 13109 tsubst_copy_and_build (tree t, 13110 tree args, 13111 tsubst_flags_t complain, 13112 tree in_decl, 13113 bool function_p, 13114 bool integral_constant_expression_p) 13115 { 13116 #define RECUR(NODE) \ 13117 tsubst_copy_and_build (NODE, args, complain, in_decl, \ 13118 /*function_p=*/false, \ 13119 integral_constant_expression_p) 13120 13121 tree op1; 13122 13123 if (t == NULL_TREE || t == error_mark_node) 13124 return t; 13125 13126 switch (TREE_CODE (t)) 13127 { 13128 case USING_DECL: 13129 t = DECL_NAME (t); 13130 /* Fall through. */ 13131 case IDENTIFIER_NODE: 13132 { 13133 tree decl; 13134 cp_id_kind idk; 13135 bool non_integral_constant_expression_p; 13136 const char *error_msg; 13137 13138 if (IDENTIFIER_TYPENAME_P (t)) 13139 { 13140 tree new_type = tsubst (TREE_TYPE (t), args, complain, in_decl); 13141 t = mangle_conv_op_name_for_type (new_type); 13142 } 13143 13144 /* Look up the name. */ 13145 decl = lookup_name (t); 13146 13147 /* By convention, expressions use ERROR_MARK_NODE to indicate 13148 failure, not NULL_TREE. */ 13149 if (decl == NULL_TREE) 13150 decl = error_mark_node; 13151 13152 decl = finish_id_expression (t, decl, NULL_TREE, 13153 &idk, 13154 integral_constant_expression_p, 13155 /*allow_non_integral_constant_expression_p=*/(cxx_dialect >= cxx0x), 13156 &non_integral_constant_expression_p, 13157 /*template_p=*/false, 13158 /*done=*/true, 13159 /*address_p=*/false, 13160 /*template_arg_p=*/false, 13161 &error_msg, 13162 input_location); 13163 if (error_msg) 13164 error (error_msg); 13165 if (!function_p && TREE_CODE (decl) == IDENTIFIER_NODE) 13166 { 13167 if (complain & tf_error) 13168 unqualified_name_lookup_error (decl); 13169 decl = error_mark_node; 13170 } 13171 return decl; 13172 } 13173 13174 case TEMPLATE_ID_EXPR: 13175 { 13176 tree object; 13177 tree templ = RECUR (TREE_OPERAND (t, 0)); 13178 tree targs = TREE_OPERAND (t, 1); 13179 13180 if (targs) 13181 targs = tsubst_template_args (targs, args, complain, in_decl); 13182 13183 if (TREE_CODE (templ) == COMPONENT_REF) 13184 { 13185 object = TREE_OPERAND (templ, 0); 13186 templ = TREE_OPERAND (templ, 1); 13187 } 13188 else 13189 object = NULL_TREE; 13190 templ = lookup_template_function (templ, targs); 13191 13192 if (object) 13193 return build3 (COMPONENT_REF, TREE_TYPE (templ), 13194 object, templ, NULL_TREE); 13195 else 13196 return baselink_for_fns (templ); 13197 } 13198 13199 case INDIRECT_REF: 13200 { 13201 tree r = RECUR (TREE_OPERAND (t, 0)); 13202 13203 if (REFERENCE_REF_P (t)) 13204 { 13205 /* A type conversion to reference type will be enclosed in 13206 such an indirect ref, but the substitution of the cast 13207 will have also added such an indirect ref. */ 13208 if (TREE_CODE (TREE_TYPE (r)) == REFERENCE_TYPE) 13209 r = convert_from_reference (r); 13210 } 13211 else 13212 r = build_x_indirect_ref (r, RO_UNARY_STAR, complain); 13213 return r; 13214 } 13215 13216 case NOP_EXPR: 13217 return build_nop 13218 (tsubst (TREE_TYPE (t), args, complain, in_decl), 13219 RECUR (TREE_OPERAND (t, 0))); 13220 13221 case IMPLICIT_CONV_EXPR: 13222 { 13223 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); 13224 tree expr = RECUR (TREE_OPERAND (t, 0)); 13225 int flags = LOOKUP_IMPLICIT; 13226 if (IMPLICIT_CONV_EXPR_DIRECT_INIT (t)) 13227 flags = LOOKUP_NORMAL; 13228 return perform_implicit_conversion_flags (type, expr, complain, 13229 flags); 13230 } 13231 13232 case CONVERT_EXPR: 13233 return build1 13234 (CONVERT_EXPR, 13235 tsubst (TREE_TYPE (t), args, complain, in_decl), 13236 RECUR (TREE_OPERAND (t, 0))); 13237 13238 case CAST_EXPR: 13239 case REINTERPRET_CAST_EXPR: 13240 case CONST_CAST_EXPR: 13241 case DYNAMIC_CAST_EXPR: 13242 case STATIC_CAST_EXPR: 13243 { 13244 tree type; 13245 tree op; 13246 13247 type = tsubst (TREE_TYPE (t), args, complain, in_decl); 13248 if (integral_constant_expression_p 13249 && !cast_valid_in_integral_constant_expression_p (type)) 13250 { 13251 if (complain & tf_error) 13252 error ("a cast to a type other than an integral or " 13253 "enumeration type cannot appear in a constant-expression"); 13254 return error_mark_node; 13255 } 13256 13257 op = RECUR (TREE_OPERAND (t, 0)); 13258 13259 switch (TREE_CODE (t)) 13260 { 13261 case CAST_EXPR: 13262 return build_functional_cast (type, op, complain); 13263 case REINTERPRET_CAST_EXPR: 13264 return build_reinterpret_cast (type, op, complain); 13265 case CONST_CAST_EXPR: 13266 return build_const_cast (type, op, complain); 13267 case DYNAMIC_CAST_EXPR: 13268 return build_dynamic_cast (type, op, complain); 13269 case STATIC_CAST_EXPR: 13270 return build_static_cast (type, op, complain); 13271 default: 13272 gcc_unreachable (); 13273 } 13274 } 13275 13276 case POSTDECREMENT_EXPR: 13277 case POSTINCREMENT_EXPR: 13278 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0), 13279 args, complain, in_decl); 13280 return build_x_unary_op (TREE_CODE (t), op1, complain); 13281 13282 case PREDECREMENT_EXPR: 13283 case PREINCREMENT_EXPR: 13284 case NEGATE_EXPR: 13285 case BIT_NOT_EXPR: 13286 case ABS_EXPR: 13287 case TRUTH_NOT_EXPR: 13288 case UNARY_PLUS_EXPR: /* Unary + */ 13289 case REALPART_EXPR: 13290 case IMAGPART_EXPR: 13291 return build_x_unary_op (TREE_CODE (t), RECUR (TREE_OPERAND (t, 0)), 13292 complain); 13293 13294 case FIX_TRUNC_EXPR: 13295 return cp_build_unary_op (FIX_TRUNC_EXPR, RECUR (TREE_OPERAND (t, 0)), 13296 0, complain); 13297 13298 case ADDR_EXPR: 13299 op1 = TREE_OPERAND (t, 0); 13300 if (TREE_CODE (op1) == LABEL_DECL) 13301 return finish_label_address_expr (DECL_NAME (op1), 13302 EXPR_LOCATION (op1)); 13303 if (TREE_CODE (op1) == SCOPE_REF) 13304 op1 = tsubst_qualified_id (op1, args, complain, in_decl, 13305 /*done=*/true, /*address_p=*/true); 13306 else 13307 op1 = tsubst_non_call_postfix_expression (op1, args, complain, 13308 in_decl); 13309 return build_x_unary_op (ADDR_EXPR, op1, complain); 13310 13311 case PLUS_EXPR: 13312 case MINUS_EXPR: 13313 case MULT_EXPR: 13314 case TRUNC_DIV_EXPR: 13315 case CEIL_DIV_EXPR: 13316 case FLOOR_DIV_EXPR: 13317 case ROUND_DIV_EXPR: 13318 case EXACT_DIV_EXPR: 13319 case BIT_AND_EXPR: 13320 case BIT_IOR_EXPR: 13321 case BIT_XOR_EXPR: 13322 case TRUNC_MOD_EXPR: 13323 case FLOOR_MOD_EXPR: 13324 case TRUTH_ANDIF_EXPR: 13325 case TRUTH_ORIF_EXPR: 13326 case TRUTH_AND_EXPR: 13327 case TRUTH_OR_EXPR: 13328 case RSHIFT_EXPR: 13329 case LSHIFT_EXPR: 13330 case RROTATE_EXPR: 13331 case LROTATE_EXPR: 13332 case EQ_EXPR: 13333 case NE_EXPR: 13334 case MAX_EXPR: 13335 case MIN_EXPR: 13336 case LE_EXPR: 13337 case GE_EXPR: 13338 case LT_EXPR: 13339 case GT_EXPR: 13340 case MEMBER_REF: 13341 case DOTSTAR_EXPR: 13342 { 13343 tree r = build_x_binary_op 13344 (TREE_CODE (t), 13345 RECUR (TREE_OPERAND (t, 0)), 13346 (TREE_NO_WARNING (TREE_OPERAND (t, 0)) 13347 ? ERROR_MARK 13348 : TREE_CODE (TREE_OPERAND (t, 0))), 13349 RECUR (TREE_OPERAND (t, 1)), 13350 (TREE_NO_WARNING (TREE_OPERAND (t, 1)) 13351 ? ERROR_MARK 13352 : TREE_CODE (TREE_OPERAND (t, 1))), 13353 /*overload=*/NULL, 13354 complain); 13355 if (EXPR_P (r) && TREE_NO_WARNING (t)) 13356 TREE_NO_WARNING (r) = TREE_NO_WARNING (t); 13357 return r; 13358 } 13359 13360 case SCOPE_REF: 13361 return tsubst_qualified_id (t, args, complain, in_decl, /*done=*/true, 13362 /*address_p=*/false); 13363 case ARRAY_REF: 13364 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0), 13365 args, complain, in_decl); 13366 return build_x_array_ref (op1, RECUR (TREE_OPERAND (t, 1)), complain); 13367 13368 case SIZEOF_EXPR: 13369 if (PACK_EXPANSION_P (TREE_OPERAND (t, 0))) 13370 return tsubst_copy (t, args, complain, in_decl); 13371 /* Fall through */ 13372 13373 case ALIGNOF_EXPR: 13374 op1 = TREE_OPERAND (t, 0); 13375 if (!args) 13376 { 13377 /* When there are no ARGS, we are trying to evaluate a 13378 non-dependent expression from the parser. Trying to do 13379 the substitutions may not work. */ 13380 if (!TYPE_P (op1)) 13381 op1 = TREE_TYPE (op1); 13382 } 13383 else 13384 { 13385 ++cp_unevaluated_operand; 13386 ++c_inhibit_evaluation_warnings; 13387 op1 = tsubst_copy_and_build (op1, args, complain, in_decl, 13388 /*function_p=*/false, 13389 /*integral_constant_expression_p=*/false); 13390 --cp_unevaluated_operand; 13391 --c_inhibit_evaluation_warnings; 13392 } 13393 if (TYPE_P (op1)) 13394 return cxx_sizeof_or_alignof_type (op1, TREE_CODE (t), 13395 complain & tf_error); 13396 else 13397 return cxx_sizeof_or_alignof_expr (op1, TREE_CODE (t), 13398 complain & tf_error); 13399 13400 case AT_ENCODE_EXPR: 13401 { 13402 op1 = TREE_OPERAND (t, 0); 13403 ++cp_unevaluated_operand; 13404 ++c_inhibit_evaluation_warnings; 13405 op1 = tsubst_copy_and_build (op1, args, complain, in_decl, 13406 /*function_p=*/false, 13407 /*integral_constant_expression_p=*/false); 13408 --cp_unevaluated_operand; 13409 --c_inhibit_evaluation_warnings; 13410 return objc_build_encode_expr (op1); 13411 } 13412 13413 case NOEXCEPT_EXPR: 13414 op1 = TREE_OPERAND (t, 0); 13415 ++cp_unevaluated_operand; 13416 ++c_inhibit_evaluation_warnings; 13417 op1 = tsubst_copy_and_build (op1, args, complain, in_decl, 13418 /*function_p=*/false, 13419 /*integral_constant_expression_p=*/false); 13420 --cp_unevaluated_operand; 13421 --c_inhibit_evaluation_warnings; 13422 return finish_noexcept_expr (op1, complain); 13423 13424 case MODOP_EXPR: 13425 { 13426 tree r = build_x_modify_expr 13427 (RECUR (TREE_OPERAND (t, 0)), 13428 TREE_CODE (TREE_OPERAND (t, 1)), 13429 RECUR (TREE_OPERAND (t, 2)), 13430 complain); 13431 /* TREE_NO_WARNING must be set if either the expression was 13432 parenthesized or it uses an operator such as >>= rather 13433 than plain assignment. In the former case, it was already 13434 set and must be copied. In the latter case, 13435 build_x_modify_expr sets it and it must not be reset 13436 here. */ 13437 if (TREE_NO_WARNING (t)) 13438 TREE_NO_WARNING (r) = TREE_NO_WARNING (t); 13439 return r; 13440 } 13441 13442 case ARROW_EXPR: 13443 op1 = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0), 13444 args, complain, in_decl); 13445 /* Remember that there was a reference to this entity. */ 13446 if (DECL_P (op1)) 13447 mark_used (op1); 13448 return build_x_arrow (op1); 13449 13450 case NEW_EXPR: 13451 { 13452 tree placement = RECUR (TREE_OPERAND (t, 0)); 13453 tree init = RECUR (TREE_OPERAND (t, 3)); 13454 VEC(tree,gc) *placement_vec; 13455 VEC(tree,gc) *init_vec; 13456 tree ret; 13457 13458 if (placement == NULL_TREE) 13459 placement_vec = NULL; 13460 else 13461 { 13462 placement_vec = make_tree_vector (); 13463 for (; placement != NULL_TREE; placement = TREE_CHAIN (placement)) 13464 VEC_safe_push (tree, gc, placement_vec, TREE_VALUE (placement)); 13465 } 13466 13467 /* If there was an initializer in the original tree, but it 13468 instantiated to an empty list, then we should pass a 13469 non-NULL empty vector to tell build_new that it was an 13470 empty initializer() rather than no initializer. This can 13471 only happen when the initializer is a pack expansion whose 13472 parameter packs are of length zero. */ 13473 if (init == NULL_TREE && TREE_OPERAND (t, 3) == NULL_TREE) 13474 init_vec = NULL; 13475 else 13476 { 13477 init_vec = make_tree_vector (); 13478 if (init == void_zero_node) 13479 gcc_assert (init_vec != NULL); 13480 else 13481 { 13482 for (; init != NULL_TREE; init = TREE_CHAIN (init)) 13483 VEC_safe_push (tree, gc, init_vec, TREE_VALUE (init)); 13484 } 13485 } 13486 13487 ret = build_new (&placement_vec, 13488 tsubst (TREE_OPERAND (t, 1), args, complain, in_decl), 13489 RECUR (TREE_OPERAND (t, 2)), 13490 &init_vec, 13491 NEW_EXPR_USE_GLOBAL (t), 13492 complain); 13493 13494 if (placement_vec != NULL) 13495 release_tree_vector (placement_vec); 13496 if (init_vec != NULL) 13497 release_tree_vector (init_vec); 13498 13499 return ret; 13500 } 13501 13502 case DELETE_EXPR: 13503 return delete_sanity 13504 (RECUR (TREE_OPERAND (t, 0)), 13505 RECUR (TREE_OPERAND (t, 1)), 13506 DELETE_EXPR_USE_VEC (t), 13507 DELETE_EXPR_USE_GLOBAL (t), 13508 complain); 13509 13510 case COMPOUND_EXPR: 13511 return build_x_compound_expr (RECUR (TREE_OPERAND (t, 0)), 13512 RECUR (TREE_OPERAND (t, 1)), 13513 complain); 13514 13515 case CALL_EXPR: 13516 { 13517 tree function; 13518 VEC(tree,gc) *call_args; 13519 unsigned int nargs, i; 13520 bool qualified_p; 13521 bool koenig_p; 13522 tree ret; 13523 13524 function = CALL_EXPR_FN (t); 13525 /* When we parsed the expression, we determined whether or 13526 not Koenig lookup should be performed. */ 13527 koenig_p = KOENIG_LOOKUP_P (t); 13528 if (TREE_CODE (function) == SCOPE_REF) 13529 { 13530 qualified_p = true; 13531 function = tsubst_qualified_id (function, args, complain, in_decl, 13532 /*done=*/false, 13533 /*address_p=*/false); 13534 } 13535 else if (koenig_p && TREE_CODE (function) == IDENTIFIER_NODE) 13536 { 13537 /* Do nothing; calling tsubst_copy_and_build on an identifier 13538 would incorrectly perform unqualified lookup again. 13539 13540 Note that we can also have an IDENTIFIER_NODE if the earlier 13541 unqualified lookup found a member function; in that case 13542 koenig_p will be false and we do want to do the lookup 13543 again to find the instantiated member function. 13544 13545 FIXME but doing that causes c++/15272, so we need to stop 13546 using IDENTIFIER_NODE in that situation. */ 13547 qualified_p = false; 13548 } 13549 else 13550 { 13551 if (TREE_CODE (function) == COMPONENT_REF) 13552 { 13553 tree op = TREE_OPERAND (function, 1); 13554 13555 qualified_p = (TREE_CODE (op) == SCOPE_REF 13556 || (BASELINK_P (op) 13557 && BASELINK_QUALIFIED_P (op))); 13558 } 13559 else 13560 qualified_p = false; 13561 13562 function = tsubst_copy_and_build (function, args, complain, 13563 in_decl, 13564 !qualified_p, 13565 integral_constant_expression_p); 13566 13567 if (BASELINK_P (function)) 13568 qualified_p = true; 13569 } 13570 13571 nargs = call_expr_nargs (t); 13572 call_args = make_tree_vector (); 13573 for (i = 0; i < nargs; ++i) 13574 { 13575 tree arg = CALL_EXPR_ARG (t, i); 13576 13577 if (!PACK_EXPANSION_P (arg)) 13578 VEC_safe_push (tree, gc, call_args, 13579 RECUR (CALL_EXPR_ARG (t, i))); 13580 else 13581 { 13582 /* Expand the pack expansion and push each entry onto 13583 CALL_ARGS. */ 13584 arg = tsubst_pack_expansion (arg, args, complain, in_decl); 13585 if (TREE_CODE (arg) == TREE_VEC) 13586 { 13587 unsigned int len, j; 13588 13589 len = TREE_VEC_LENGTH (arg); 13590 for (j = 0; j < len; ++j) 13591 { 13592 tree value = TREE_VEC_ELT (arg, j); 13593 if (value != NULL_TREE) 13594 value = convert_from_reference (value); 13595 VEC_safe_push (tree, gc, call_args, value); 13596 } 13597 } 13598 else 13599 { 13600 /* A partial substitution. Add one entry. */ 13601 VEC_safe_push (tree, gc, call_args, arg); 13602 } 13603 } 13604 } 13605 13606 /* We do not perform argument-dependent lookup if normal 13607 lookup finds a non-function, in accordance with the 13608 expected resolution of DR 218. */ 13609 if (koenig_p 13610 && ((is_overloaded_fn (function) 13611 /* If lookup found a member function, the Koenig lookup is 13612 not appropriate, even if an unqualified-name was used 13613 to denote the function. */ 13614 && !DECL_FUNCTION_MEMBER_P (get_first_fn (function))) 13615 || TREE_CODE (function) == IDENTIFIER_NODE) 13616 /* Only do this when substitution turns a dependent call 13617 into a non-dependent call. */ 13618 && type_dependent_expression_p_push (t) 13619 && !any_type_dependent_arguments_p (call_args)) 13620 function = perform_koenig_lookup (function, call_args, false, 13621 tf_none); 13622 13623 if (TREE_CODE (function) == IDENTIFIER_NODE 13624 && !any_type_dependent_arguments_p (call_args)) 13625 { 13626 if (koenig_p && (complain & tf_warning_or_error)) 13627 { 13628 /* For backwards compatibility and good diagnostics, try 13629 the unqualified lookup again if we aren't in SFINAE 13630 context. */ 13631 tree unq = (tsubst_copy_and_build 13632 (function, args, complain, in_decl, true, 13633 integral_constant_expression_p)); 13634 if (unq == error_mark_node) 13635 return error_mark_node; 13636 13637 if (unq != function) 13638 { 13639 tree fn = unq; 13640 if (TREE_CODE (fn) == INDIRECT_REF) 13641 fn = TREE_OPERAND (fn, 0); 13642 if (TREE_CODE (fn) == COMPONENT_REF) 13643 fn = TREE_OPERAND (fn, 1); 13644 if (is_overloaded_fn (fn)) 13645 fn = get_first_fn (fn); 13646 permerror (EXPR_LOC_OR_HERE (t), 13647 "%qD was not declared in this scope, " 13648 "and no declarations were found by " 13649 "argument-dependent lookup at the point " 13650 "of instantiation", function); 13651 if (!DECL_P (fn)) 13652 /* Can't say anything more. */; 13653 else if (DECL_CLASS_SCOPE_P (fn)) 13654 { 13655 inform (EXPR_LOC_OR_HERE (t), 13656 "declarations in dependent base %qT are " 13657 "not found by unqualified lookup", 13658 DECL_CLASS_CONTEXT (fn)); 13659 if (current_class_ptr) 13660 inform (EXPR_LOC_OR_HERE (t), 13661 "use %<this->%D%> instead", function); 13662 else 13663 inform (EXPR_LOC_OR_HERE (t), 13664 "use %<%T::%D%> instead", 13665 current_class_name, function); 13666 } 13667 else 13668 inform (0, "%q+D declared here, later in the " 13669 "translation unit", fn); 13670 function = unq; 13671 } 13672 } 13673 if (TREE_CODE (function) == IDENTIFIER_NODE) 13674 { 13675 unqualified_name_lookup_error (function); 13676 release_tree_vector (call_args); 13677 return error_mark_node; 13678 } 13679 } 13680 13681 /* Remember that there was a reference to this entity. */ 13682 if (DECL_P (function)) 13683 mark_used (function); 13684 13685 if (TREE_CODE (function) == OFFSET_REF) 13686 ret = build_offset_ref_call_from_tree (function, &call_args); 13687 else if (TREE_CODE (function) == COMPONENT_REF) 13688 { 13689 tree instance = TREE_OPERAND (function, 0); 13690 tree fn = TREE_OPERAND (function, 1); 13691 13692 if (processing_template_decl 13693 && (type_dependent_expression_p (instance) 13694 || (!BASELINK_P (fn) 13695 && TREE_CODE (fn) != FIELD_DECL) 13696 || type_dependent_expression_p (fn) 13697 || any_type_dependent_arguments_p (call_args))) 13698 ret = build_nt_call_vec (function, call_args); 13699 else if (!BASELINK_P (fn)) 13700 ret = finish_call_expr (function, &call_args, 13701 /*disallow_virtual=*/false, 13702 /*koenig_p=*/false, 13703 complain); 13704 else 13705 ret = (build_new_method_call 13706 (instance, fn, 13707 &call_args, NULL_TREE, 13708 qualified_p ? LOOKUP_NONVIRTUAL : LOOKUP_NORMAL, 13709 /*fn_p=*/NULL, 13710 complain)); 13711 } 13712 else 13713 ret = finish_call_expr (function, &call_args, 13714 /*disallow_virtual=*/qualified_p, 13715 koenig_p, 13716 complain); 13717 13718 release_tree_vector (call_args); 13719 13720 return ret; 13721 } 13722 13723 case COND_EXPR: 13724 return build_x_conditional_expr 13725 (RECUR (TREE_OPERAND (t, 0)), 13726 RECUR (TREE_OPERAND (t, 1)), 13727 RECUR (TREE_OPERAND (t, 2)), 13728 complain); 13729 13730 case PSEUDO_DTOR_EXPR: 13731 return finish_pseudo_destructor_expr 13732 (RECUR (TREE_OPERAND (t, 0)), 13733 RECUR (TREE_OPERAND (t, 1)), 13734 tsubst (TREE_OPERAND (t, 2), args, complain, in_decl)); 13735 13736 case TREE_LIST: 13737 { 13738 tree purpose, value, chain; 13739 13740 if (t == void_list_node) 13741 return t; 13742 13743 if ((TREE_PURPOSE (t) && PACK_EXPANSION_P (TREE_PURPOSE (t))) 13744 || (TREE_VALUE (t) && PACK_EXPANSION_P (TREE_VALUE (t)))) 13745 { 13746 /* We have pack expansions, so expand those and 13747 create a new list out of it. */ 13748 tree purposevec = NULL_TREE; 13749 tree valuevec = NULL_TREE; 13750 tree chain; 13751 int i, len = -1; 13752 13753 /* Expand the argument expressions. */ 13754 if (TREE_PURPOSE (t)) 13755 purposevec = tsubst_pack_expansion (TREE_PURPOSE (t), args, 13756 complain, in_decl); 13757 if (TREE_VALUE (t)) 13758 valuevec = tsubst_pack_expansion (TREE_VALUE (t), args, 13759 complain, in_decl); 13760 13761 /* Build the rest of the list. */ 13762 chain = TREE_CHAIN (t); 13763 if (chain && chain != void_type_node) 13764 chain = RECUR (chain); 13765 13766 /* Determine the number of arguments. */ 13767 if (purposevec && TREE_CODE (purposevec) == TREE_VEC) 13768 { 13769 len = TREE_VEC_LENGTH (purposevec); 13770 gcc_assert (!valuevec || len == TREE_VEC_LENGTH (valuevec)); 13771 } 13772 else if (TREE_CODE (valuevec) == TREE_VEC) 13773 len = TREE_VEC_LENGTH (valuevec); 13774 else 13775 { 13776 /* Since we only performed a partial substitution into 13777 the argument pack, we only return a single list 13778 node. */ 13779 if (purposevec == TREE_PURPOSE (t) 13780 && valuevec == TREE_VALUE (t) 13781 && chain == TREE_CHAIN (t)) 13782 return t; 13783 13784 return tree_cons (purposevec, valuevec, chain); 13785 } 13786 13787 /* Convert the argument vectors into a TREE_LIST */ 13788 i = len; 13789 while (i > 0) 13790 { 13791 /* Grab the Ith values. */ 13792 i--; 13793 purpose = purposevec ? TREE_VEC_ELT (purposevec, i) 13794 : NULL_TREE; 13795 value 13796 = valuevec ? convert_from_reference (TREE_VEC_ELT (valuevec, i)) 13797 : NULL_TREE; 13798 13799 /* Build the list (backwards). */ 13800 chain = tree_cons (purpose, value, chain); 13801 } 13802 13803 return chain; 13804 } 13805 13806 purpose = TREE_PURPOSE (t); 13807 if (purpose) 13808 purpose = RECUR (purpose); 13809 value = TREE_VALUE (t); 13810 if (value) 13811 value = RECUR (value); 13812 chain = TREE_CHAIN (t); 13813 if (chain && chain != void_type_node) 13814 chain = RECUR (chain); 13815 if (purpose == TREE_PURPOSE (t) 13816 && value == TREE_VALUE (t) 13817 && chain == TREE_CHAIN (t)) 13818 return t; 13819 return tree_cons (purpose, value, chain); 13820 } 13821 13822 case COMPONENT_REF: 13823 { 13824 tree object; 13825 tree object_type; 13826 tree member; 13827 13828 object = tsubst_non_call_postfix_expression (TREE_OPERAND (t, 0), 13829 args, complain, in_decl); 13830 /* Remember that there was a reference to this entity. */ 13831 if (DECL_P (object)) 13832 mark_used (object); 13833 object_type = TREE_TYPE (object); 13834 13835 member = TREE_OPERAND (t, 1); 13836 if (BASELINK_P (member)) 13837 member = tsubst_baselink (member, 13838 non_reference (TREE_TYPE (object)), 13839 args, complain, in_decl); 13840 else 13841 member = tsubst_copy (member, args, complain, in_decl); 13842 if (member == error_mark_node) 13843 return error_mark_node; 13844 13845 if (type_dependent_expression_p (object)) 13846 /* We can't do much here. */; 13847 else if (!CLASS_TYPE_P (object_type)) 13848 { 13849 if (SCALAR_TYPE_P (object_type)) 13850 { 13851 tree s = NULL_TREE; 13852 tree dtor = member; 13853 13854 if (TREE_CODE (dtor) == SCOPE_REF) 13855 { 13856 s = TREE_OPERAND (dtor, 0); 13857 dtor = TREE_OPERAND (dtor, 1); 13858 } 13859 if (TREE_CODE (dtor) == BIT_NOT_EXPR) 13860 { 13861 dtor = TREE_OPERAND (dtor, 0); 13862 if (TYPE_P (dtor)) 13863 return finish_pseudo_destructor_expr (object, s, dtor); 13864 } 13865 } 13866 } 13867 else if (TREE_CODE (member) == SCOPE_REF 13868 && TREE_CODE (TREE_OPERAND (member, 1)) == TEMPLATE_ID_EXPR) 13869 { 13870 /* Lookup the template functions now that we know what the 13871 scope is. */ 13872 tree scope = TREE_OPERAND (member, 0); 13873 tree tmpl = TREE_OPERAND (TREE_OPERAND (member, 1), 0); 13874 tree args = TREE_OPERAND (TREE_OPERAND (member, 1), 1); 13875 member = lookup_qualified_name (scope, tmpl, 13876 /*is_type_p=*/false, 13877 /*complain=*/false); 13878 if (BASELINK_P (member)) 13879 { 13880 BASELINK_FUNCTIONS (member) 13881 = build_nt (TEMPLATE_ID_EXPR, BASELINK_FUNCTIONS (member), 13882 args); 13883 member = (adjust_result_of_qualified_name_lookup 13884 (member, BINFO_TYPE (BASELINK_BINFO (member)), 13885 object_type)); 13886 } 13887 else 13888 { 13889 qualified_name_lookup_error (scope, tmpl, member, 13890 input_location); 13891 return error_mark_node; 13892 } 13893 } 13894 else if (TREE_CODE (member) == SCOPE_REF 13895 && !CLASS_TYPE_P (TREE_OPERAND (member, 0)) 13896 && TREE_CODE (TREE_OPERAND (member, 0)) != NAMESPACE_DECL) 13897 { 13898 if (complain & tf_error) 13899 { 13900 if (TYPE_P (TREE_OPERAND (member, 0))) 13901 error ("%qT is not a class or namespace", 13902 TREE_OPERAND (member, 0)); 13903 else 13904 error ("%qD is not a class or namespace", 13905 TREE_OPERAND (member, 0)); 13906 } 13907 return error_mark_node; 13908 } 13909 else if (TREE_CODE (member) == FIELD_DECL) 13910 return finish_non_static_data_member (member, object, NULL_TREE); 13911 13912 return finish_class_member_access_expr (object, member, 13913 /*template_p=*/false, 13914 complain); 13915 } 13916 13917 case THROW_EXPR: 13918 return build_throw 13919 (RECUR (TREE_OPERAND (t, 0))); 13920 13921 case CONSTRUCTOR: 13922 { 13923 VEC(constructor_elt,gc) *n; 13924 constructor_elt *ce; 13925 unsigned HOST_WIDE_INT idx; 13926 tree type = tsubst (TREE_TYPE (t), args, complain, in_decl); 13927 bool process_index_p; 13928 int newlen; 13929 bool need_copy_p = false; 13930 tree r; 13931 13932 if (type == error_mark_node) 13933 return error_mark_node; 13934 13935 /* digest_init will do the wrong thing if we let it. */ 13936 if (type && TYPE_PTRMEMFUNC_P (type)) 13937 return t; 13938 13939 /* We do not want to process the index of aggregate 13940 initializers as they are identifier nodes which will be 13941 looked up by digest_init. */ 13942 process_index_p = !(type && MAYBE_CLASS_TYPE_P (type)); 13943 13944 n = VEC_copy (constructor_elt, gc, CONSTRUCTOR_ELTS (t)); 13945 newlen = VEC_length (constructor_elt, n); 13946 FOR_EACH_VEC_ELT (constructor_elt, n, idx, ce) 13947 { 13948 if (ce->index && process_index_p) 13949 ce->index = RECUR (ce->index); 13950 13951 if (PACK_EXPANSION_P (ce->value)) 13952 { 13953 /* Substitute into the pack expansion. */ 13954 ce->value = tsubst_pack_expansion (ce->value, args, complain, 13955 in_decl); 13956 13957 if (ce->value == error_mark_node 13958 || PACK_EXPANSION_P (ce->value)) 13959 ; 13960 else if (TREE_VEC_LENGTH (ce->value) == 1) 13961 /* Just move the argument into place. */ 13962 ce->value = TREE_VEC_ELT (ce->value, 0); 13963 else 13964 { 13965 /* Update the length of the final CONSTRUCTOR 13966 arguments vector, and note that we will need to 13967 copy.*/ 13968 newlen = newlen + TREE_VEC_LENGTH (ce->value) - 1; 13969 need_copy_p = true; 13970 } 13971 } 13972 else 13973 ce->value = RECUR (ce->value); 13974 } 13975 13976 if (need_copy_p) 13977 { 13978 VEC(constructor_elt,gc) *old_n = n; 13979 13980 n = VEC_alloc (constructor_elt, gc, newlen); 13981 FOR_EACH_VEC_ELT (constructor_elt, old_n, idx, ce) 13982 { 13983 if (TREE_CODE (ce->value) == TREE_VEC) 13984 { 13985 int i, len = TREE_VEC_LENGTH (ce->value); 13986 for (i = 0; i < len; ++i) 13987 CONSTRUCTOR_APPEND_ELT (n, 0, 13988 TREE_VEC_ELT (ce->value, i)); 13989 } 13990 else 13991 CONSTRUCTOR_APPEND_ELT (n, 0, ce->value); 13992 } 13993 } 13994 13995 r = build_constructor (init_list_type_node, n); 13996 CONSTRUCTOR_IS_DIRECT_INIT (r) = CONSTRUCTOR_IS_DIRECT_INIT (t); 13997 13998 if (TREE_HAS_CONSTRUCTOR (t)) 13999 return finish_compound_literal (type, r, complain); 14000 14001 TREE_TYPE (r) = type; 14002 return r; 14003 } 14004 14005 case TYPEID_EXPR: 14006 { 14007 tree operand_0 = TREE_OPERAND (t, 0); 14008 if (TYPE_P (operand_0)) 14009 { 14010 operand_0 = tsubst (operand_0, args, complain, in_decl); 14011 return get_typeid (operand_0); 14012 } 14013 else 14014 { 14015 operand_0 = RECUR (operand_0); 14016 return build_typeid (operand_0); 14017 } 14018 } 14019 14020 case VAR_DECL: 14021 if (!args) 14022 return t; 14023 /* Fall through */ 14024 14025 case PARM_DECL: 14026 { 14027 tree r = tsubst_copy (t, args, complain, in_decl); 14028 14029 if (TREE_CODE (TREE_TYPE (t)) != REFERENCE_TYPE) 14030 /* If the original type was a reference, we'll be wrapped in 14031 the appropriate INDIRECT_REF. */ 14032 r = convert_from_reference (r); 14033 return r; 14034 } 14035 14036 case VA_ARG_EXPR: 14037 return build_x_va_arg (RECUR (TREE_OPERAND (t, 0)), 14038 tsubst (TREE_TYPE (t), args, complain, in_decl)); 14039 14040 case OFFSETOF_EXPR: 14041 return finish_offsetof (RECUR (TREE_OPERAND (t, 0))); 14042 14043 case TRAIT_EXPR: 14044 { 14045 tree type1 = tsubst_copy (TRAIT_EXPR_TYPE1 (t), args, 14046 complain, in_decl); 14047 14048 tree type2 = TRAIT_EXPR_TYPE2 (t); 14049 if (type2) 14050 type2 = tsubst_copy (type2, args, complain, in_decl); 14051 14052 return finish_trait_expr (TRAIT_EXPR_KIND (t), type1, type2); 14053 } 14054 14055 case STMT_EXPR: 14056 { 14057 tree old_stmt_expr = cur_stmt_expr; 14058 tree stmt_expr = begin_stmt_expr (); 14059 14060 cur_stmt_expr = stmt_expr; 14061 tsubst_expr (STMT_EXPR_STMT (t), args, complain, in_decl, 14062 integral_constant_expression_p); 14063 stmt_expr = finish_stmt_expr (stmt_expr, false); 14064 cur_stmt_expr = old_stmt_expr; 14065 14066 /* If the resulting list of expression statement is empty, 14067 fold it further into void_zero_node. */ 14068 if (empty_expr_stmt_p (stmt_expr)) 14069 stmt_expr = void_zero_node; 14070 14071 return stmt_expr; 14072 } 14073 14074 case CONST_DECL: 14075 t = tsubst_copy (t, args, complain, in_decl); 14076 /* As in finish_id_expression, we resolve enumeration constants 14077 to their underlying values. */ 14078 if (TREE_CODE (t) == CONST_DECL && !processing_template_decl) 14079 { 14080 used_types_insert (TREE_TYPE (t)); 14081 return DECL_INITIAL (t); 14082 } 14083 return t; 14084 14085 case LAMBDA_EXPR: 14086 { 14087 tree r = build_lambda_expr (); 14088 14089 tree type = tsubst (LAMBDA_EXPR_CLOSURE (t), args, complain, NULL_TREE); 14090 LAMBDA_EXPR_CLOSURE (r) = type; 14091 CLASSTYPE_LAMBDA_EXPR (type) = r; 14092 14093 LAMBDA_EXPR_LOCATION (r) 14094 = LAMBDA_EXPR_LOCATION (t); 14095 LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (r) 14096 = LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (t); 14097 LAMBDA_EXPR_MUTABLE_P (r) = LAMBDA_EXPR_MUTABLE_P (t); 14098 LAMBDA_EXPR_DISCRIMINATOR (r) 14099 = (LAMBDA_EXPR_DISCRIMINATOR (t)); 14100 LAMBDA_EXPR_EXTRA_SCOPE (r) 14101 = RECUR (LAMBDA_EXPR_EXTRA_SCOPE (t)); 14102 if (LAMBDA_EXPR_RETURN_TYPE (t) == dependent_lambda_return_type_node) 14103 { 14104 LAMBDA_EXPR_RETURN_TYPE (r) = dependent_lambda_return_type_node; 14105 LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (r) = true; 14106 } 14107 else 14108 LAMBDA_EXPR_RETURN_TYPE (r) 14109 = tsubst (LAMBDA_EXPR_RETURN_TYPE (t), args, complain, in_decl); 14110 14111 gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (t) == NULL_TREE 14112 && LAMBDA_EXPR_PENDING_PROXIES (t) == NULL); 14113 14114 /* Do this again now that LAMBDA_EXPR_EXTRA_SCOPE is set. */ 14115 determine_visibility (TYPE_NAME (type)); 14116 /* Now that we know visibility, instantiate the type so we have a 14117 declaration of the op() for later calls to lambda_function. */ 14118 complete_type (type); 14119 14120 /* The capture list refers to closure members, so this needs to 14121 wait until after we finish instantiating the type. Also keep 14122 any captures that may have been added during instantiation. */ 14123 LAMBDA_EXPR_CAPTURE_LIST (r) 14124 = chainon (RECUR (LAMBDA_EXPR_CAPTURE_LIST (t)), 14125 LAMBDA_EXPR_CAPTURE_LIST (r)); 14126 LAMBDA_EXPR_THIS_CAPTURE (r) = NULL_TREE; 14127 14128 return build_lambda_object (r); 14129 } 14130 14131 case TARGET_EXPR: 14132 /* We can get here for a constant initializer of non-dependent type. 14133 FIXME stop folding in cp_parser_initializer_clause. */ 14134 { 14135 tree r = get_target_expr (RECUR (TARGET_EXPR_INITIAL (t))); 14136 return r; 14137 } 14138 14139 case TRANSACTION_EXPR: 14140 return tsubst_expr(t, args, complain, in_decl, 14141 integral_constant_expression_p); 14142 14143 default: 14144 /* Handle Objective-C++ constructs, if appropriate. */ 14145 { 14146 tree subst 14147 = objcp_tsubst_copy_and_build (t, args, complain, 14148 in_decl, /*function_p=*/false); 14149 if (subst) 14150 return subst; 14151 } 14152 return tsubst_copy (t, args, complain, in_decl); 14153 } 14154 14155 #undef RECUR 14156 } 14157 14158 /* Verify that the instantiated ARGS are valid. For type arguments, 14159 make sure that the type's linkage is ok. For non-type arguments, 14160 make sure they are constants if they are integral or enumerations. 14161 Emit an error under control of COMPLAIN, and return TRUE on error. */ 14162 14163 static bool 14164 check_instantiated_arg (tree tmpl, tree t, tsubst_flags_t complain) 14165 { 14166 if (ARGUMENT_PACK_P (t)) 14167 { 14168 tree vec = ARGUMENT_PACK_ARGS (t); 14169 int len = TREE_VEC_LENGTH (vec); 14170 bool result = false; 14171 int i; 14172 14173 for (i = 0; i < len; ++i) 14174 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (vec, i), complain)) 14175 result = true; 14176 return result; 14177 } 14178 else if (TYPE_P (t)) 14179 { 14180 /* [basic.link]: A name with no linkage (notably, the name 14181 of a class or enumeration declared in a local scope) 14182 shall not be used to declare an entity with linkage. 14183 This implies that names with no linkage cannot be used as 14184 template arguments 14185 14186 DR 757 relaxes this restriction for C++0x. */ 14187 tree nt = (cxx_dialect > cxx98 ? NULL_TREE 14188 : no_linkage_check (t, /*relaxed_p=*/false)); 14189 14190 if (nt) 14191 { 14192 /* DR 488 makes use of a type with no linkage cause 14193 type deduction to fail. */ 14194 if (complain & tf_error) 14195 { 14196 if (TYPE_ANONYMOUS_P (nt)) 14197 error ("%qT is/uses anonymous type", t); 14198 else 14199 error ("template argument for %qD uses local type %qT", 14200 tmpl, t); 14201 } 14202 return true; 14203 } 14204 /* In order to avoid all sorts of complications, we do not 14205 allow variably-modified types as template arguments. */ 14206 else if (variably_modified_type_p (t, NULL_TREE)) 14207 { 14208 if (complain & tf_error) 14209 error ("%qT is a variably modified type", t); 14210 return true; 14211 } 14212 } 14213 /* A non-type argument of integral or enumerated type must be a 14214 constant. */ 14215 else if (TREE_TYPE (t) 14216 && INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (t)) 14217 && !TREE_CONSTANT (t)) 14218 { 14219 if (complain & tf_error) 14220 error ("integral expression %qE is not constant", t); 14221 return true; 14222 } 14223 return false; 14224 } 14225 14226 static bool 14227 check_instantiated_args (tree tmpl, tree args, tsubst_flags_t complain) 14228 { 14229 int ix, len = DECL_NTPARMS (tmpl); 14230 bool result = false; 14231 14232 for (ix = 0; ix != len; ix++) 14233 { 14234 if (check_instantiated_arg (tmpl, TREE_VEC_ELT (args, ix), complain)) 14235 result = true; 14236 } 14237 if (result && (complain & tf_error)) 14238 error (" trying to instantiate %qD", tmpl); 14239 return result; 14240 } 14241 14242 /* In C++0x, it's possible to have a function template whose type depends 14243 on itself recursively. This is most obvious with decltype, but can also 14244 occur with enumeration scope (c++/48969). So we need to catch infinite 14245 recursion and reject the substitution at deduction time; this function 14246 will return error_mark_node for any repeated substitution. 14247 14248 This also catches excessive recursion such as when f<N> depends on 14249 f<N-1> across all integers, and returns error_mark_node for all the 14250 substitutions back up to the initial one. 14251 14252 This is, of course, not reentrant. */ 14253 14254 static tree 14255 deduction_tsubst_fntype (tree fn, tree targs, tsubst_flags_t complain) 14256 { 14257 static bool excessive_deduction_depth; 14258 static int deduction_depth; 14259 struct pending_template *old_last_pend = last_pending_template; 14260 struct tinst_level *old_error_tinst = last_error_tinst_level; 14261 14262 tree fntype = TREE_TYPE (fn); 14263 tree tinst; 14264 tree r; 14265 14266 if (excessive_deduction_depth) 14267 return error_mark_node; 14268 14269 tinst = build_tree_list (fn, targs); 14270 if (!push_tinst_level (tinst)) 14271 { 14272 excessive_deduction_depth = true; 14273 ggc_free (tinst); 14274 return error_mark_node; 14275 } 14276 14277 input_location = DECL_SOURCE_LOCATION (fn); 14278 ++deduction_depth; 14279 push_deduction_access_scope (fn); 14280 r = tsubst (fntype, targs, complain, NULL_TREE); 14281 pop_deduction_access_scope (fn); 14282 --deduction_depth; 14283 14284 if (excessive_deduction_depth) 14285 { 14286 r = error_mark_node; 14287 if (deduction_depth == 0) 14288 /* Reset once we're all the way out. */ 14289 excessive_deduction_depth = false; 14290 } 14291 14292 pop_tinst_level (); 14293 /* We can't free this if a pending_template entry or last_error_tinst_level 14294 is pointing at it. */ 14295 if (last_pending_template == old_last_pend 14296 && last_error_tinst_level == old_error_tinst) 14297 ggc_free (tinst); 14298 return r; 14299 } 14300 14301 /* Instantiate the indicated variable or function template TMPL with 14302 the template arguments in TARG_PTR. */ 14303 14304 static tree 14305 instantiate_template_1 (tree tmpl, tree orig_args, tsubst_flags_t complain) 14306 { 14307 tree targ_ptr = orig_args; 14308 tree fndecl; 14309 tree gen_tmpl; 14310 tree spec; 14311 14312 if (tmpl == error_mark_node) 14313 return error_mark_node; 14314 14315 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL); 14316 14317 /* If this function is a clone, handle it specially. */ 14318 if (DECL_CLONED_FUNCTION_P (tmpl)) 14319 { 14320 tree spec; 14321 tree clone; 14322 14323 /* Use DECL_ABSTRACT_ORIGIN because only FUNCTION_DECLs have 14324 DECL_CLONED_FUNCTION. */ 14325 spec = instantiate_template (DECL_ABSTRACT_ORIGIN (tmpl), 14326 targ_ptr, complain); 14327 if (spec == error_mark_node) 14328 return error_mark_node; 14329 14330 /* Look for the clone. */ 14331 FOR_EACH_CLONE (clone, spec) 14332 if (DECL_NAME (clone) == DECL_NAME (tmpl)) 14333 return clone; 14334 /* We should always have found the clone by now. */ 14335 gcc_unreachable (); 14336 return NULL_TREE; 14337 } 14338 14339 /* Check to see if we already have this specialization. */ 14340 gen_tmpl = most_general_template (tmpl); 14341 if (tmpl != gen_tmpl) 14342 /* The TMPL is a partial instantiation. To get a full set of 14343 arguments we must add the arguments used to perform the 14344 partial instantiation. */ 14345 targ_ptr = add_outermost_template_args (DECL_TI_ARGS (tmpl), 14346 targ_ptr); 14347 14348 /* It would be nice to avoid hashing here and then again in tsubst_decl, 14349 but it doesn't seem to be on the hot path. */ 14350 spec = retrieve_specialization (gen_tmpl, targ_ptr, 0); 14351 14352 gcc_assert (tmpl == gen_tmpl 14353 || ((fndecl = retrieve_specialization (tmpl, orig_args, 0)) 14354 == spec) 14355 || fndecl == NULL_TREE); 14356 14357 if (spec != NULL_TREE) 14358 return spec; 14359 14360 if (check_instantiated_args (gen_tmpl, INNERMOST_TEMPLATE_ARGS (targ_ptr), 14361 complain)) 14362 return error_mark_node; 14363 14364 /* We are building a FUNCTION_DECL, during which the access of its 14365 parameters and return types have to be checked. However this 14366 FUNCTION_DECL which is the desired context for access checking 14367 is not built yet. We solve this chicken-and-egg problem by 14368 deferring all checks until we have the FUNCTION_DECL. */ 14369 push_deferring_access_checks (dk_deferred); 14370 14371 /* Instantiation of the function happens in the context of the function 14372 template, not the context of the overload resolution we're doing. */ 14373 push_to_top_level (); 14374 if (DECL_CLASS_SCOPE_P (gen_tmpl)) 14375 { 14376 tree ctx = tsubst (DECL_CONTEXT (gen_tmpl), targ_ptr, 14377 complain, gen_tmpl); 14378 push_nested_class (ctx); 14379 } 14380 /* Substitute template parameters to obtain the specialization. */ 14381 fndecl = tsubst (DECL_TEMPLATE_RESULT (gen_tmpl), 14382 targ_ptr, complain, gen_tmpl); 14383 if (DECL_CLASS_SCOPE_P (gen_tmpl)) 14384 pop_nested_class (); 14385 pop_from_top_level (); 14386 14387 if (fndecl == error_mark_node) 14388 return error_mark_node; 14389 14390 /* Now we know the specialization, compute access previously 14391 deferred. */ 14392 push_access_scope (fndecl); 14393 14394 /* Some typedefs referenced from within the template code need to be access 14395 checked at template instantiation time, i.e now. These types were 14396 added to the template at parsing time. Let's get those and perfom 14397 the acces checks then. */ 14398 perform_typedefs_access_check (DECL_TEMPLATE_RESULT (tmpl), targ_ptr); 14399 perform_deferred_access_checks (); 14400 pop_access_scope (fndecl); 14401 pop_deferring_access_checks (); 14402 14403 /* The DECL_TI_TEMPLATE should always be the immediate parent 14404 template, not the most general template. */ 14405 DECL_TI_TEMPLATE (fndecl) = tmpl; 14406 14407 /* If we've just instantiated the main entry point for a function, 14408 instantiate all the alternate entry points as well. We do this 14409 by cloning the instantiation of the main entry point, not by 14410 instantiating the template clones. */ 14411 if (DECL_CHAIN (gen_tmpl) && DECL_CLONED_FUNCTION_P (DECL_CHAIN (gen_tmpl))) 14412 clone_function_decl (fndecl, /*update_method_vec_p=*/0); 14413 14414 return fndecl; 14415 } 14416 14417 /* Wrapper for instantiate_template_1. */ 14418 14419 tree 14420 instantiate_template (tree tmpl, tree orig_args, tsubst_flags_t complain) 14421 { 14422 tree ret; 14423 timevar_push (TV_TEMPLATE_INST); 14424 ret = instantiate_template_1 (tmpl, orig_args, complain); 14425 timevar_pop (TV_TEMPLATE_INST); 14426 return ret; 14427 } 14428 14429 /* We're going to do deduction substitution on the type of TMPL, a function 14430 template. In C++11 mode, push into that access scope. In C++03 mode, 14431 disable access checking. */ 14432 14433 static void 14434 push_deduction_access_scope (tree tmpl) 14435 { 14436 if (cxx_dialect >= cxx0x) 14437 { 14438 int ptd = processing_template_decl; 14439 push_access_scope (DECL_TEMPLATE_RESULT (tmpl)); 14440 /* Preserve processing_template_decl across push_to_top_level. */ 14441 if (ptd && !processing_template_decl) 14442 ++processing_template_decl; 14443 } 14444 else 14445 push_deferring_access_checks (dk_no_check); 14446 } 14447 14448 /* And pop back out. */ 14449 14450 static void 14451 pop_deduction_access_scope (tree tmpl) 14452 { 14453 if (cxx_dialect >= cxx0x) 14454 pop_access_scope (DECL_TEMPLATE_RESULT (tmpl)); 14455 else 14456 pop_deferring_access_checks (); 14457 } 14458 14459 /* PARM is a template parameter pack for FN. Returns true iff 14460 PARM is used in a deducible way in the argument list of FN. */ 14461 14462 static bool 14463 pack_deducible_p (tree parm, tree fn) 14464 { 14465 tree t = FUNCTION_FIRST_USER_PARMTYPE (fn); 14466 for (; t; t = TREE_CHAIN (t)) 14467 { 14468 tree type = TREE_VALUE (t); 14469 tree packs; 14470 if (!PACK_EXPANSION_P (type)) 14471 continue; 14472 for (packs = PACK_EXPANSION_PARAMETER_PACKS (type); 14473 packs; packs = TREE_CHAIN (packs)) 14474 if (TREE_VALUE (packs) == parm) 14475 { 14476 /* The template parameter pack is used in a function parameter 14477 pack. If this is the end of the parameter list, the 14478 template parameter pack is deducible. */ 14479 if (TREE_CHAIN (t) == void_list_node) 14480 return true; 14481 else 14482 /* Otherwise, not. Well, it could be deduced from 14483 a non-pack parameter, but doing so would end up with 14484 a deduction mismatch, so don't bother. */ 14485 return false; 14486 } 14487 } 14488 /* The template parameter pack isn't used in any function parameter 14489 packs, but it might be used deeper, e.g. tuple<Args...>. */ 14490 return true; 14491 } 14492 14493 /* The FN is a TEMPLATE_DECL for a function. ARGS is an array with 14494 NARGS elements of the arguments that are being used when calling 14495 it. TARGS is a vector into which the deduced template arguments 14496 are placed. 14497 14498 Return zero for success, 2 for an incomplete match that doesn't resolve 14499 all the types, and 1 for complete failure. An error message will be 14500 printed only for an incomplete match. 14501 14502 If FN is a conversion operator, or we are trying to produce a specific 14503 specialization, RETURN_TYPE is the return type desired. 14504 14505 The EXPLICIT_TARGS are explicit template arguments provided via a 14506 template-id. 14507 14508 The parameter STRICT is one of: 14509 14510 DEDUCE_CALL: 14511 We are deducing arguments for a function call, as in 14512 [temp.deduct.call]. 14513 14514 DEDUCE_CONV: 14515 We are deducing arguments for a conversion function, as in 14516 [temp.deduct.conv]. 14517 14518 DEDUCE_EXACT: 14519 We are deducing arguments when doing an explicit instantiation 14520 as in [temp.explicit], when determining an explicit specialization 14521 as in [temp.expl.spec], or when taking the address of a function 14522 template, as in [temp.deduct.funcaddr]. */ 14523 14524 int 14525 fn_type_unification (tree fn, 14526 tree explicit_targs, 14527 tree targs, 14528 const tree *args, 14529 unsigned int nargs, 14530 tree return_type, 14531 unification_kind_t strict, 14532 int flags, 14533 bool explain_p) 14534 { 14535 tree parms; 14536 tree fntype; 14537 int result; 14538 14539 gcc_assert (TREE_CODE (fn) == TEMPLATE_DECL); 14540 14541 fntype = TREE_TYPE (fn); 14542 if (explicit_targs) 14543 { 14544 /* [temp.deduct] 14545 14546 The specified template arguments must match the template 14547 parameters in kind (i.e., type, nontype, template), and there 14548 must not be more arguments than there are parameters; 14549 otherwise type deduction fails. 14550 14551 Nontype arguments must match the types of the corresponding 14552 nontype template parameters, or must be convertible to the 14553 types of the corresponding nontype parameters as specified in 14554 _temp.arg.nontype_, otherwise type deduction fails. 14555 14556 All references in the function type of the function template 14557 to the corresponding template parameters are replaced by the 14558 specified template argument values. If a substitution in a 14559 template parameter or in the function type of the function 14560 template results in an invalid type, type deduction fails. */ 14561 tree tparms = DECL_INNERMOST_TEMPLATE_PARMS (fn); 14562 int i, len = TREE_VEC_LENGTH (tparms); 14563 tree converted_args; 14564 bool incomplete = false; 14565 14566 if (explicit_targs == error_mark_node) 14567 return unify_invalid (explain_p); 14568 14569 converted_args 14570 = (coerce_template_parms (tparms, explicit_targs, NULL_TREE, 14571 (explain_p 14572 ? tf_warning_or_error 14573 : tf_none), 14574 /*require_all_args=*/false, 14575 /*use_default_args=*/false)); 14576 if (converted_args == error_mark_node) 14577 return 1; 14578 14579 /* Substitute the explicit args into the function type. This is 14580 necessary so that, for instance, explicitly declared function 14581 arguments can match null pointed constants. If we were given 14582 an incomplete set of explicit args, we must not do semantic 14583 processing during substitution as we could create partial 14584 instantiations. */ 14585 for (i = 0; i < len; i++) 14586 { 14587 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i)); 14588 bool parameter_pack = false; 14589 tree targ = TREE_VEC_ELT (converted_args, i); 14590 14591 /* Dig out the actual parm. */ 14592 if (TREE_CODE (parm) == TYPE_DECL 14593 || TREE_CODE (parm) == TEMPLATE_DECL) 14594 { 14595 parm = TREE_TYPE (parm); 14596 parameter_pack = TEMPLATE_TYPE_PARAMETER_PACK (parm); 14597 } 14598 else if (TREE_CODE (parm) == PARM_DECL) 14599 { 14600 parm = DECL_INITIAL (parm); 14601 parameter_pack = TEMPLATE_PARM_PARAMETER_PACK (parm); 14602 } 14603 14604 if (!parameter_pack && targ == NULL_TREE) 14605 /* No explicit argument for this template parameter. */ 14606 incomplete = true; 14607 14608 if (parameter_pack && pack_deducible_p (parm, fn)) 14609 { 14610 /* Mark the argument pack as "incomplete". We could 14611 still deduce more arguments during unification. 14612 We remove this mark in type_unification_real. */ 14613 if (targ) 14614 { 14615 ARGUMENT_PACK_INCOMPLETE_P(targ) = 1; 14616 ARGUMENT_PACK_EXPLICIT_ARGS (targ) 14617 = ARGUMENT_PACK_ARGS (targ); 14618 } 14619 14620 /* We have some incomplete argument packs. */ 14621 incomplete = true; 14622 } 14623 } 14624 14625 processing_template_decl += incomplete; 14626 fntype = deduction_tsubst_fntype (fn, converted_args, 14627 (explain_p 14628 ? tf_warning_or_error 14629 : tf_none)); 14630 processing_template_decl -= incomplete; 14631 14632 if (fntype == error_mark_node) 14633 return 1; 14634 14635 /* Place the explicitly specified arguments in TARGS. */ 14636 for (i = NUM_TMPL_ARGS (converted_args); i--;) 14637 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (converted_args, i); 14638 } 14639 14640 /* Never do unification on the 'this' parameter. */ 14641 parms = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (fntype)); 14642 14643 if (return_type) 14644 { 14645 tree *new_args; 14646 14647 parms = tree_cons (NULL_TREE, TREE_TYPE (fntype), parms); 14648 new_args = XALLOCAVEC (tree, nargs + 1); 14649 new_args[0] = return_type; 14650 memcpy (new_args + 1, args, nargs * sizeof (tree)); 14651 args = new_args; 14652 ++nargs; 14653 } 14654 14655 /* We allow incomplete unification without an error message here 14656 because the standard doesn't seem to explicitly prohibit it. Our 14657 callers must be ready to deal with unification failures in any 14658 event. */ 14659 result = type_unification_real (DECL_INNERMOST_TEMPLATE_PARMS (fn), 14660 targs, parms, args, nargs, /*subr=*/0, 14661 strict, flags, explain_p); 14662 14663 /* Now that we have bindings for all of the template arguments, 14664 ensure that the arguments deduced for the template template 14665 parameters have compatible template parameter lists. We cannot 14666 check this property before we have deduced all template 14667 arguments, because the template parameter types of a template 14668 template parameter might depend on prior template parameters 14669 deduced after the template template parameter. The following 14670 ill-formed example illustrates this issue: 14671 14672 template<typename T, template<T> class C> void f(C<5>, T); 14673 14674 template<int N> struct X {}; 14675 14676 void g() { 14677 f(X<5>(), 5l); // error: template argument deduction fails 14678 } 14679 14680 The template parameter list of 'C' depends on the template type 14681 parameter 'T', but 'C' is deduced to 'X' before 'T' is deduced to 14682 'long'. Thus, we can't check that 'C' cannot bind to 'X' at the 14683 time that we deduce 'C'. */ 14684 if (result == 0 14685 && !template_template_parm_bindings_ok_p 14686 (DECL_INNERMOST_TEMPLATE_PARMS (fn), targs)) 14687 return unify_inconsistent_template_template_parameters (explain_p); 14688 14689 if (result == 0) 14690 /* All is well so far. Now, check: 14691 14692 [temp.deduct] 14693 14694 When all template arguments have been deduced, all uses of 14695 template parameters in nondeduced contexts are replaced with 14696 the corresponding deduced argument values. If the 14697 substitution results in an invalid type, as described above, 14698 type deduction fails. */ 14699 { 14700 tree substed = deduction_tsubst_fntype (fn, targs, 14701 (explain_p 14702 ? tf_warning_or_error 14703 : tf_none)); 14704 if (substed == error_mark_node) 14705 return 1; 14706 14707 /* If we're looking for an exact match, check that what we got 14708 is indeed an exact match. It might not be if some template 14709 parameters are used in non-deduced contexts. */ 14710 if (strict == DEDUCE_EXACT) 14711 { 14712 unsigned int i; 14713 14714 tree sarg 14715 = skip_artificial_parms_for (fn, TYPE_ARG_TYPES (substed)); 14716 if (return_type) 14717 sarg = tree_cons (NULL_TREE, TREE_TYPE (substed), sarg); 14718 for (i = 0; i < nargs && sarg; ++i, sarg = TREE_CHAIN (sarg)) 14719 if (!same_type_p (args[i], TREE_VALUE (sarg))) 14720 return unify_type_mismatch (explain_p, args[i], 14721 TREE_VALUE (sarg)); 14722 } 14723 } 14724 14725 return result; 14726 } 14727 14728 /* Adjust types before performing type deduction, as described in 14729 [temp.deduct.call] and [temp.deduct.conv]. The rules in these two 14730 sections are symmetric. PARM is the type of a function parameter 14731 or the return type of the conversion function. ARG is the type of 14732 the argument passed to the call, or the type of the value 14733 initialized with the result of the conversion function. 14734 ARG_EXPR is the original argument expression, which may be null. */ 14735 14736 static int 14737 maybe_adjust_types_for_deduction (unification_kind_t strict, 14738 tree* parm, 14739 tree* arg, 14740 tree arg_expr) 14741 { 14742 int result = 0; 14743 14744 switch (strict) 14745 { 14746 case DEDUCE_CALL: 14747 break; 14748 14749 case DEDUCE_CONV: 14750 { 14751 /* Swap PARM and ARG throughout the remainder of this 14752 function; the handling is precisely symmetric since PARM 14753 will initialize ARG rather than vice versa. */ 14754 tree* temp = parm; 14755 parm = arg; 14756 arg = temp; 14757 break; 14758 } 14759 14760 case DEDUCE_EXACT: 14761 /* Core issue #873: Do the DR606 thing (see below) for these cases, 14762 too, but here handle it by stripping the reference from PARM 14763 rather than by adding it to ARG. */ 14764 if (TREE_CODE (*parm) == REFERENCE_TYPE 14765 && TYPE_REF_IS_RVALUE (*parm) 14766 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM 14767 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED 14768 && TREE_CODE (*arg) == REFERENCE_TYPE 14769 && !TYPE_REF_IS_RVALUE (*arg)) 14770 *parm = TREE_TYPE (*parm); 14771 /* Nothing else to do in this case. */ 14772 return 0; 14773 14774 default: 14775 gcc_unreachable (); 14776 } 14777 14778 if (TREE_CODE (*parm) != REFERENCE_TYPE) 14779 { 14780 /* [temp.deduct.call] 14781 14782 If P is not a reference type: 14783 14784 --If A is an array type, the pointer type produced by the 14785 array-to-pointer standard conversion (_conv.array_) is 14786 used in place of A for type deduction; otherwise, 14787 14788 --If A is a function type, the pointer type produced by 14789 the function-to-pointer standard conversion 14790 (_conv.func_) is used in place of A for type deduction; 14791 otherwise, 14792 14793 --If A is a cv-qualified type, the top level 14794 cv-qualifiers of A's type are ignored for type 14795 deduction. */ 14796 if (TREE_CODE (*arg) == ARRAY_TYPE) 14797 *arg = build_pointer_type (TREE_TYPE (*arg)); 14798 else if (TREE_CODE (*arg) == FUNCTION_TYPE) 14799 *arg = build_pointer_type (*arg); 14800 else 14801 *arg = TYPE_MAIN_VARIANT (*arg); 14802 } 14803 14804 /* From C++0x [14.8.2.1/3 temp.deduct.call] (after DR606), "If P is 14805 of the form T&&, where T is a template parameter, and the argument 14806 is an lvalue, T is deduced as A& */ 14807 if (TREE_CODE (*parm) == REFERENCE_TYPE 14808 && TYPE_REF_IS_RVALUE (*parm) 14809 && TREE_CODE (TREE_TYPE (*parm)) == TEMPLATE_TYPE_PARM 14810 && cp_type_quals (TREE_TYPE (*parm)) == TYPE_UNQUALIFIED 14811 && (arg_expr ? real_lvalue_p (arg_expr) 14812 /* try_one_overload doesn't provide an arg_expr, but 14813 functions are always lvalues. */ 14814 : TREE_CODE (*arg) == FUNCTION_TYPE)) 14815 *arg = build_reference_type (*arg); 14816 14817 /* [temp.deduct.call] 14818 14819 If P is a cv-qualified type, the top level cv-qualifiers 14820 of P's type are ignored for type deduction. If P is a 14821 reference type, the type referred to by P is used for 14822 type deduction. */ 14823 *parm = TYPE_MAIN_VARIANT (*parm); 14824 if (TREE_CODE (*parm) == REFERENCE_TYPE) 14825 { 14826 *parm = TREE_TYPE (*parm); 14827 result |= UNIFY_ALLOW_OUTER_MORE_CV_QUAL; 14828 } 14829 14830 /* DR 322. For conversion deduction, remove a reference type on parm 14831 too (which has been swapped into ARG). */ 14832 if (strict == DEDUCE_CONV && TREE_CODE (*arg) == REFERENCE_TYPE) 14833 *arg = TREE_TYPE (*arg); 14834 14835 return result; 14836 } 14837 14838 /* Subroutine of unify_one_argument. PARM is a function parameter of a 14839 template which does contain any deducible template parameters; check if 14840 ARG is a suitable match for it. STRICT, FLAGS and EXPLAIN_P are as in 14841 unify_one_argument. */ 14842 14843 static int 14844 check_non_deducible_conversion (tree parm, tree arg, int strict, 14845 int flags, bool explain_p) 14846 { 14847 tree type; 14848 14849 if (!TYPE_P (arg)) 14850 type = TREE_TYPE (arg); 14851 else 14852 type = arg; 14853 14854 if (same_type_p (parm, type)) 14855 return unify_success (explain_p); 14856 14857 if (strict == DEDUCE_CONV) 14858 { 14859 if (can_convert_arg (type, parm, NULL_TREE, flags)) 14860 return unify_success (explain_p); 14861 } 14862 else if (strict != DEDUCE_EXACT) 14863 { 14864 if (can_convert_arg (parm, type, 14865 TYPE_P (arg) ? NULL_TREE : arg, 14866 flags)) 14867 return unify_success (explain_p); 14868 } 14869 14870 if (strict == DEDUCE_EXACT) 14871 return unify_type_mismatch (explain_p, parm, arg); 14872 else 14873 return unify_arg_conversion (explain_p, parm, type, arg); 14874 } 14875 14876 /* Subroutine of type_unification_real and unify_pack_expansion to 14877 handle unification of a single P/A pair. Parameters are as 14878 for those functions. */ 14879 14880 static int 14881 unify_one_argument (tree tparms, tree targs, tree parm, tree arg, 14882 int subr, unification_kind_t strict, int flags, 14883 bool explain_p) 14884 { 14885 tree arg_expr = NULL_TREE; 14886 int arg_strict; 14887 14888 if (arg == error_mark_node || parm == error_mark_node) 14889 return unify_invalid (explain_p); 14890 if (arg == unknown_type_node) 14891 /* We can't deduce anything from this, but we might get all the 14892 template args from other function args. */ 14893 return unify_success (explain_p); 14894 14895 /* FIXME uses_deducible_template_parms */ 14896 if (TYPE_P (parm) && !uses_template_parms (parm)) 14897 return check_non_deducible_conversion (parm, arg, strict, flags, 14898 explain_p); 14899 14900 switch (strict) 14901 { 14902 case DEDUCE_CALL: 14903 arg_strict = (UNIFY_ALLOW_OUTER_LEVEL 14904 | UNIFY_ALLOW_MORE_CV_QUAL 14905 | UNIFY_ALLOW_DERIVED); 14906 break; 14907 14908 case DEDUCE_CONV: 14909 arg_strict = UNIFY_ALLOW_LESS_CV_QUAL; 14910 break; 14911 14912 case DEDUCE_EXACT: 14913 arg_strict = UNIFY_ALLOW_NONE; 14914 break; 14915 14916 default: 14917 gcc_unreachable (); 14918 } 14919 14920 /* We only do these transformations if this is the top-level 14921 parameter_type_list in a call or declaration matching; in other 14922 situations (nested function declarators, template argument lists) we 14923 won't be comparing a type to an expression, and we don't do any type 14924 adjustments. */ 14925 if (!subr) 14926 { 14927 if (!TYPE_P (arg)) 14928 { 14929 gcc_assert (TREE_TYPE (arg) != NULL_TREE); 14930 if (type_unknown_p (arg)) 14931 { 14932 /* [temp.deduct.type] A template-argument can be 14933 deduced from a pointer to function or pointer 14934 to member function argument if the set of 14935 overloaded functions does not contain function 14936 templates and at most one of a set of 14937 overloaded functions provides a unique 14938 match. */ 14939 14940 if (resolve_overloaded_unification 14941 (tparms, targs, parm, arg, strict, 14942 arg_strict, explain_p)) 14943 return unify_success (explain_p); 14944 return unify_overload_resolution_failure (explain_p, arg); 14945 } 14946 14947 arg_expr = arg; 14948 arg = unlowered_expr_type (arg); 14949 if (arg == error_mark_node) 14950 return unify_invalid (explain_p); 14951 } 14952 14953 arg_strict |= 14954 maybe_adjust_types_for_deduction (strict, &parm, &arg, arg_expr); 14955 } 14956 else 14957 gcc_assert ((TYPE_P (parm) || TREE_CODE (parm) == TEMPLATE_DECL) 14958 == (TYPE_P (arg) || TREE_CODE (arg) == TEMPLATE_DECL)); 14959 14960 /* For deduction from an init-list we need the actual list. */ 14961 if (arg_expr && BRACE_ENCLOSED_INITIALIZER_P (arg_expr)) 14962 arg = arg_expr; 14963 return unify (tparms, targs, parm, arg, arg_strict, explain_p); 14964 } 14965 14966 /* Most parms like fn_type_unification. 14967 14968 If SUBR is 1, we're being called recursively (to unify the 14969 arguments of a function or method parameter of a function 14970 template). */ 14971 14972 static int 14973 type_unification_real (tree tparms, 14974 tree targs, 14975 tree xparms, 14976 const tree *xargs, 14977 unsigned int xnargs, 14978 int subr, 14979 unification_kind_t strict, 14980 int flags, 14981 bool explain_p) 14982 { 14983 tree parm, arg; 14984 int i; 14985 int ntparms = TREE_VEC_LENGTH (tparms); 14986 int saw_undeduced = 0; 14987 tree parms; 14988 const tree *args; 14989 unsigned int nargs; 14990 unsigned int ia; 14991 14992 gcc_assert (TREE_CODE (tparms) == TREE_VEC); 14993 gcc_assert (xparms == NULL_TREE || TREE_CODE (xparms) == TREE_LIST); 14994 gcc_assert (ntparms > 0); 14995 14996 /* Reset the number of non-defaulted template arguments contained 14997 in TARGS. */ 14998 NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs) = NULL_TREE; 14999 15000 again: 15001 parms = xparms; 15002 args = xargs; 15003 nargs = xnargs; 15004 15005 ia = 0; 15006 while (parms && parms != void_list_node 15007 && ia < nargs) 15008 { 15009 parm = TREE_VALUE (parms); 15010 15011 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION 15012 && (!TREE_CHAIN (parms) || TREE_CHAIN (parms) == void_list_node)) 15013 /* For a function parameter pack that occurs at the end of the 15014 parameter-declaration-list, the type A of each remaining 15015 argument of the call is compared with the type P of the 15016 declarator-id of the function parameter pack. */ 15017 break; 15018 15019 parms = TREE_CHAIN (parms); 15020 15021 if (TREE_CODE (parm) == TYPE_PACK_EXPANSION) 15022 /* For a function parameter pack that does not occur at the 15023 end of the parameter-declaration-list, the type of the 15024 parameter pack is a non-deduced context. */ 15025 continue; 15026 15027 arg = args[ia]; 15028 ++ia; 15029 15030 if (unify_one_argument (tparms, targs, parm, arg, subr, strict, 15031 flags, explain_p)) 15032 return 1; 15033 } 15034 15035 if (parms 15036 && parms != void_list_node 15037 && TREE_CODE (TREE_VALUE (parms)) == TYPE_PACK_EXPANSION) 15038 { 15039 /* Unify the remaining arguments with the pack expansion type. */ 15040 tree argvec; 15041 tree parmvec = make_tree_vec (1); 15042 15043 /* Allocate a TREE_VEC and copy in all of the arguments */ 15044 argvec = make_tree_vec (nargs - ia); 15045 for (i = 0; ia < nargs; ++ia, ++i) 15046 TREE_VEC_ELT (argvec, i) = args[ia]; 15047 15048 /* Copy the parameter into parmvec. */ 15049 TREE_VEC_ELT (parmvec, 0) = TREE_VALUE (parms); 15050 if (unify_pack_expansion (tparms, targs, parmvec, argvec, strict, 15051 /*subr=*/subr, explain_p)) 15052 return 1; 15053 15054 /* Advance to the end of the list of parameters. */ 15055 parms = TREE_CHAIN (parms); 15056 } 15057 15058 /* Fail if we've reached the end of the parm list, and more args 15059 are present, and the parm list isn't variadic. */ 15060 if (ia < nargs && parms == void_list_node) 15061 return unify_too_many_arguments (explain_p, nargs, ia); 15062 /* Fail if parms are left and they don't have default values. */ 15063 if (parms && parms != void_list_node 15064 && TREE_PURPOSE (parms) == NULL_TREE) 15065 { 15066 unsigned int count = nargs; 15067 tree p = parms; 15068 while (p && p != void_list_node) 15069 { 15070 count++; 15071 p = TREE_CHAIN (p); 15072 } 15073 return unify_too_few_arguments (explain_p, ia, count); 15074 } 15075 15076 if (!subr) 15077 { 15078 tsubst_flags_t complain = (explain_p 15079 ? tf_warning_or_error 15080 : tf_none); 15081 15082 for (i = 0; i < ntparms; i++) 15083 { 15084 tree targ = TREE_VEC_ELT (targs, i); 15085 tree tparm = TREE_VEC_ELT (tparms, i); 15086 15087 /* Clear the "incomplete" flags on all argument packs now so that 15088 substituting them into later default arguments works. */ 15089 if (targ && ARGUMENT_PACK_P (targ)) 15090 { 15091 ARGUMENT_PACK_INCOMPLETE_P (targ) = 0; 15092 ARGUMENT_PACK_EXPLICIT_ARGS (targ) = NULL_TREE; 15093 } 15094 15095 if (targ || tparm == error_mark_node) 15096 continue; 15097 tparm = TREE_VALUE (tparm); 15098 15099 /* If this is an undeduced nontype parameter that depends on 15100 a type parameter, try another pass; its type may have been 15101 deduced from a later argument than the one from which 15102 this parameter can be deduced. */ 15103 if (TREE_CODE (tparm) == PARM_DECL 15104 && uses_template_parms (TREE_TYPE (tparm)) 15105 && !saw_undeduced++) 15106 goto again; 15107 15108 /* Core issue #226 (C++0x) [temp.deduct]: 15109 15110 If a template argument has not been deduced, its 15111 default template argument, if any, is used. 15112 15113 When we are in C++98 mode, TREE_PURPOSE will either 15114 be NULL_TREE or ERROR_MARK_NODE, so we do not need 15115 to explicitly check cxx_dialect here. */ 15116 if (TREE_PURPOSE (TREE_VEC_ELT (tparms, i))) 15117 { 15118 tree parm = TREE_VALUE (TREE_VEC_ELT (tparms, i)); 15119 tree arg = TREE_PURPOSE (TREE_VEC_ELT (tparms, i)); 15120 location_t save_loc = input_location; 15121 if (DECL_P (parm)) 15122 input_location = DECL_SOURCE_LOCATION (parm); 15123 arg = tsubst_template_arg (arg, targs, complain, NULL_TREE); 15124 arg = convert_template_argument (parm, arg, targs, complain, 15125 i, NULL_TREE); 15126 input_location = save_loc; 15127 if (arg == error_mark_node) 15128 return 1; 15129 else 15130 { 15131 TREE_VEC_ELT (targs, i) = arg; 15132 /* The position of the first default template argument, 15133 is also the number of non-defaulted arguments in TARGS. 15134 Record that. */ 15135 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs)) 15136 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, i); 15137 continue; 15138 } 15139 } 15140 15141 /* If the type parameter is a parameter pack, then it will 15142 be deduced to an empty parameter pack. */ 15143 if (template_parameter_pack_p (tparm)) 15144 { 15145 tree arg; 15146 15147 if (TREE_CODE (tparm) == TEMPLATE_PARM_INDEX) 15148 { 15149 arg = make_node (NONTYPE_ARGUMENT_PACK); 15150 TREE_TYPE (arg) = TREE_TYPE (TEMPLATE_PARM_DECL (tparm)); 15151 TREE_CONSTANT (arg) = 1; 15152 } 15153 else 15154 arg = cxx_make_type (TYPE_ARGUMENT_PACK); 15155 15156 SET_ARGUMENT_PACK_ARGS (arg, make_tree_vec (0)); 15157 15158 TREE_VEC_ELT (targs, i) = arg; 15159 continue; 15160 } 15161 15162 return unify_parameter_deduction_failure (explain_p, tparm); 15163 } 15164 } 15165 #ifdef ENABLE_CHECKING 15166 if (!NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs)) 15167 SET_NON_DEFAULT_TEMPLATE_ARGS_COUNT (targs, TREE_VEC_LENGTH (targs)); 15168 #endif 15169 15170 return unify_success (explain_p); 15171 } 15172 15173 /* Subroutine of type_unification_real. Args are like the variables 15174 at the call site. ARG is an overloaded function (or template-id); 15175 we try deducing template args from each of the overloads, and if 15176 only one succeeds, we go with that. Modifies TARGS and returns 15177 true on success. */ 15178 15179 static bool 15180 resolve_overloaded_unification (tree tparms, 15181 tree targs, 15182 tree parm, 15183 tree arg, 15184 unification_kind_t strict, 15185 int sub_strict, 15186 bool explain_p) 15187 { 15188 tree tempargs = copy_node (targs); 15189 int good = 0; 15190 tree goodfn = NULL_TREE; 15191 bool addr_p; 15192 15193 if (TREE_CODE (arg) == ADDR_EXPR) 15194 { 15195 arg = TREE_OPERAND (arg, 0); 15196 addr_p = true; 15197 } 15198 else 15199 addr_p = false; 15200 15201 if (TREE_CODE (arg) == COMPONENT_REF) 15202 /* Handle `&x' where `x' is some static or non-static member 15203 function name. */ 15204 arg = TREE_OPERAND (arg, 1); 15205 15206 if (TREE_CODE (arg) == OFFSET_REF) 15207 arg = TREE_OPERAND (arg, 1); 15208 15209 /* Strip baselink information. */ 15210 if (BASELINK_P (arg)) 15211 arg = BASELINK_FUNCTIONS (arg); 15212 15213 if (TREE_CODE (arg) == TEMPLATE_ID_EXPR) 15214 { 15215 /* If we got some explicit template args, we need to plug them into 15216 the affected templates before we try to unify, in case the 15217 explicit args will completely resolve the templates in question. */ 15218 15219 int ok = 0; 15220 tree expl_subargs = TREE_OPERAND (arg, 1); 15221 arg = TREE_OPERAND (arg, 0); 15222 15223 for (; arg; arg = OVL_NEXT (arg)) 15224 { 15225 tree fn = OVL_CURRENT (arg); 15226 tree subargs, elem; 15227 15228 if (TREE_CODE (fn) != TEMPLATE_DECL) 15229 continue; 15230 15231 ++processing_template_decl; 15232 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn), 15233 expl_subargs, /*check_ret=*/false); 15234 if (subargs && !any_dependent_template_arguments_p (subargs)) 15235 { 15236 elem = tsubst (TREE_TYPE (fn), subargs, tf_none, NULL_TREE); 15237 if (try_one_overload (tparms, targs, tempargs, parm, 15238 elem, strict, sub_strict, addr_p, explain_p) 15239 && (!goodfn || !same_type_p (goodfn, elem))) 15240 { 15241 goodfn = elem; 15242 ++good; 15243 } 15244 } 15245 else if (subargs) 15246 ++ok; 15247 --processing_template_decl; 15248 } 15249 /* If no templates (or more than one) are fully resolved by the 15250 explicit arguments, this template-id is a non-deduced context; it 15251 could still be OK if we deduce all template arguments for the 15252 enclosing call through other arguments. */ 15253 if (good != 1) 15254 good = ok; 15255 } 15256 else if (TREE_CODE (arg) != OVERLOAD 15257 && TREE_CODE (arg) != FUNCTION_DECL) 15258 /* If ARG is, for example, "(0, &f)" then its type will be unknown 15259 -- but the deduction does not succeed because the expression is 15260 not just the function on its own. */ 15261 return false; 15262 else 15263 for (; arg; arg = OVL_NEXT (arg)) 15264 if (try_one_overload (tparms, targs, tempargs, parm, 15265 TREE_TYPE (OVL_CURRENT (arg)), 15266 strict, sub_strict, addr_p, explain_p) 15267 && (!goodfn || !decls_match (goodfn, OVL_CURRENT (arg)))) 15268 { 15269 goodfn = OVL_CURRENT (arg); 15270 ++good; 15271 } 15272 15273 /* [temp.deduct.type] A template-argument can be deduced from a pointer 15274 to function or pointer to member function argument if the set of 15275 overloaded functions does not contain function templates and at most 15276 one of a set of overloaded functions provides a unique match. 15277 15278 So if we found multiple possibilities, we return success but don't 15279 deduce anything. */ 15280 15281 if (good == 1) 15282 { 15283 int i = TREE_VEC_LENGTH (targs); 15284 for (; i--; ) 15285 if (TREE_VEC_ELT (tempargs, i)) 15286 TREE_VEC_ELT (targs, i) = TREE_VEC_ELT (tempargs, i); 15287 } 15288 if (good) 15289 return true; 15290 15291 return false; 15292 } 15293 15294 /* Core DR 115: In contexts where deduction is done and fails, or in 15295 contexts where deduction is not done, if a template argument list is 15296 specified and it, along with any default template arguments, identifies 15297 a single function template specialization, then the template-id is an 15298 lvalue for the function template specialization. */ 15299 15300 tree 15301 resolve_nondeduced_context (tree orig_expr) 15302 { 15303 tree expr, offset, baselink; 15304 bool addr; 15305 15306 if (!type_unknown_p (orig_expr)) 15307 return orig_expr; 15308 15309 expr = orig_expr; 15310 addr = false; 15311 offset = NULL_TREE; 15312 baselink = NULL_TREE; 15313 15314 if (TREE_CODE (expr) == ADDR_EXPR) 15315 { 15316 expr = TREE_OPERAND (expr, 0); 15317 addr = true; 15318 } 15319 if (TREE_CODE (expr) == OFFSET_REF) 15320 { 15321 offset = expr; 15322 expr = TREE_OPERAND (expr, 1); 15323 } 15324 if (BASELINK_P (expr)) 15325 { 15326 baselink = expr; 15327 expr = BASELINK_FUNCTIONS (expr); 15328 } 15329 15330 if (TREE_CODE (expr) == TEMPLATE_ID_EXPR) 15331 { 15332 int good = 0; 15333 tree goodfn = NULL_TREE; 15334 15335 /* If we got some explicit template args, we need to plug them into 15336 the affected templates before we try to unify, in case the 15337 explicit args will completely resolve the templates in question. */ 15338 15339 tree expl_subargs = TREE_OPERAND (expr, 1); 15340 tree arg = TREE_OPERAND (expr, 0); 15341 tree badfn = NULL_TREE; 15342 tree badargs = NULL_TREE; 15343 15344 for (; arg; arg = OVL_NEXT (arg)) 15345 { 15346 tree fn = OVL_CURRENT (arg); 15347 tree subargs, elem; 15348 15349 if (TREE_CODE (fn) != TEMPLATE_DECL) 15350 continue; 15351 15352 ++processing_template_decl; 15353 subargs = get_bindings (fn, DECL_TEMPLATE_RESULT (fn), 15354 expl_subargs, /*check_ret=*/false); 15355 if (subargs && !any_dependent_template_arguments_p (subargs)) 15356 { 15357 elem = instantiate_template (fn, subargs, tf_none); 15358 if (elem == error_mark_node) 15359 { 15360 badfn = fn; 15361 badargs = subargs; 15362 } 15363 else if (elem && (!goodfn || !decls_match (goodfn, elem))) 15364 { 15365 goodfn = elem; 15366 ++good; 15367 } 15368 } 15369 --processing_template_decl; 15370 } 15371 if (good == 1) 15372 { 15373 mark_used (goodfn); 15374 expr = goodfn; 15375 if (baselink) 15376 expr = build_baselink (BASELINK_BINFO (baselink), 15377 BASELINK_ACCESS_BINFO (baselink), 15378 expr, BASELINK_OPTYPE (baselink)); 15379 if (offset) 15380 { 15381 tree base 15382 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (offset, 0))); 15383 expr = build_offset_ref (base, expr, addr); 15384 } 15385 if (addr) 15386 expr = cp_build_addr_expr (expr, tf_warning_or_error); 15387 return expr; 15388 } 15389 else if (good == 0 && badargs) 15390 /* There were no good options and at least one bad one, so let the 15391 user know what the problem is. */ 15392 instantiate_template (badfn, badargs, tf_warning_or_error); 15393 } 15394 return orig_expr; 15395 } 15396 15397 /* Subroutine of resolve_overloaded_unification; does deduction for a single 15398 overload. Fills TARGS with any deduced arguments, or error_mark_node if 15399 different overloads deduce different arguments for a given parm. 15400 ADDR_P is true if the expression for which deduction is being 15401 performed was of the form "& fn" rather than simply "fn". 15402 15403 Returns 1 on success. */ 15404 15405 static int 15406 try_one_overload (tree tparms, 15407 tree orig_targs, 15408 tree targs, 15409 tree parm, 15410 tree arg, 15411 unification_kind_t strict, 15412 int sub_strict, 15413 bool addr_p, 15414 bool explain_p) 15415 { 15416 int nargs; 15417 tree tempargs; 15418 int i; 15419 15420 /* [temp.deduct.type] A template-argument can be deduced from a pointer 15421 to function or pointer to member function argument if the set of 15422 overloaded functions does not contain function templates and at most 15423 one of a set of overloaded functions provides a unique match. 15424 15425 So if this is a template, just return success. */ 15426 15427 if (uses_template_parms (arg)) 15428 return 1; 15429 15430 if (TREE_CODE (arg) == METHOD_TYPE) 15431 arg = build_ptrmemfunc_type (build_pointer_type (arg)); 15432 else if (addr_p) 15433 arg = build_pointer_type (arg); 15434 15435 sub_strict |= maybe_adjust_types_for_deduction (strict, &parm, &arg, NULL); 15436 15437 /* We don't copy orig_targs for this because if we have already deduced 15438 some template args from previous args, unify would complain when we 15439 try to deduce a template parameter for the same argument, even though 15440 there isn't really a conflict. */ 15441 nargs = TREE_VEC_LENGTH (targs); 15442 tempargs = make_tree_vec (nargs); 15443 15444 if (unify (tparms, tempargs, parm, arg, sub_strict, explain_p)) 15445 return 0; 15446 15447 /* First make sure we didn't deduce anything that conflicts with 15448 explicitly specified args. */ 15449 for (i = nargs; i--; ) 15450 { 15451 tree elt = TREE_VEC_ELT (tempargs, i); 15452 tree oldelt = TREE_VEC_ELT (orig_targs, i); 15453 15454 if (!elt) 15455 /*NOP*/; 15456 else if (uses_template_parms (elt)) 15457 /* Since we're unifying against ourselves, we will fill in 15458 template args used in the function parm list with our own 15459 template parms. Discard them. */ 15460 TREE_VEC_ELT (tempargs, i) = NULL_TREE; 15461 else if (oldelt && !template_args_equal (oldelt, elt)) 15462 return 0; 15463 } 15464 15465 for (i = nargs; i--; ) 15466 { 15467 tree elt = TREE_VEC_ELT (tempargs, i); 15468 15469 if (elt) 15470 TREE_VEC_ELT (targs, i) = elt; 15471 } 15472 15473 return 1; 15474 } 15475 15476 /* PARM is a template class (perhaps with unbound template 15477 parameters). ARG is a fully instantiated type. If ARG can be 15478 bound to PARM, return ARG, otherwise return NULL_TREE. TPARMS and 15479 TARGS are as for unify. */ 15480 15481 static tree 15482 try_class_unification (tree tparms, tree targs, tree parm, tree arg, 15483 bool explain_p) 15484 { 15485 tree copy_of_targs; 15486 15487 if (!CLASSTYPE_TEMPLATE_INFO (arg) 15488 || (most_general_template (CLASSTYPE_TI_TEMPLATE (arg)) 15489 != most_general_template (CLASSTYPE_TI_TEMPLATE (parm)))) 15490 return NULL_TREE; 15491 15492 /* We need to make a new template argument vector for the call to 15493 unify. If we used TARGS, we'd clutter it up with the result of 15494 the attempted unification, even if this class didn't work out. 15495 We also don't want to commit ourselves to all the unifications 15496 we've already done, since unification is supposed to be done on 15497 an argument-by-argument basis. In other words, consider the 15498 following pathological case: 15499 15500 template <int I, int J, int K> 15501 struct S {}; 15502 15503 template <int I, int J> 15504 struct S<I, J, 2> : public S<I, I, I>, S<J, J, J> {}; 15505 15506 template <int I, int J, int K> 15507 void f(S<I, J, K>, S<I, I, I>); 15508 15509 void g() { 15510 S<0, 0, 0> s0; 15511 S<0, 1, 2> s2; 15512 15513 f(s0, s2); 15514 } 15515 15516 Now, by the time we consider the unification involving `s2', we 15517 already know that we must have `f<0, 0, 0>'. But, even though 15518 `S<0, 1, 2>' is derived from `S<0, 0, 0>', the code is invalid 15519 because there are two ways to unify base classes of S<0, 1, 2> 15520 with S<I, I, I>. If we kept the already deduced knowledge, we 15521 would reject the possibility I=1. */ 15522 copy_of_targs = make_tree_vec (TREE_VEC_LENGTH (targs)); 15523 15524 /* If unification failed, we're done. */ 15525 if (unify (tparms, copy_of_targs, CLASSTYPE_TI_ARGS (parm), 15526 CLASSTYPE_TI_ARGS (arg), UNIFY_ALLOW_NONE, explain_p)) 15527 return NULL_TREE; 15528 15529 return arg; 15530 } 15531 15532 /* Given a template type PARM and a class type ARG, find the unique 15533 base type in ARG that is an instance of PARM. We do not examine 15534 ARG itself; only its base-classes. If there is not exactly one 15535 appropriate base class, return NULL_TREE. PARM may be the type of 15536 a partial specialization, as well as a plain template type. Used 15537 by unify. */ 15538 15539 static enum template_base_result 15540 get_template_base (tree tparms, tree targs, tree parm, tree arg, 15541 bool explain_p, tree *result) 15542 { 15543 tree rval = NULL_TREE; 15544 tree binfo; 15545 15546 gcc_assert (RECORD_OR_UNION_CODE_P (TREE_CODE (arg))); 15547 15548 binfo = TYPE_BINFO (complete_type (arg)); 15549 if (!binfo) 15550 { 15551 /* The type could not be completed. */ 15552 *result = NULL_TREE; 15553 return tbr_incomplete_type; 15554 } 15555 15556 /* Walk in inheritance graph order. The search order is not 15557 important, and this avoids multiple walks of virtual bases. */ 15558 for (binfo = TREE_CHAIN (binfo); binfo; binfo = TREE_CHAIN (binfo)) 15559 { 15560 tree r = try_class_unification (tparms, targs, parm, 15561 BINFO_TYPE (binfo), explain_p); 15562 15563 if (r) 15564 { 15565 /* If there is more than one satisfactory baseclass, then: 15566 15567 [temp.deduct.call] 15568 15569 If they yield more than one possible deduced A, the type 15570 deduction fails. 15571 15572 applies. */ 15573 if (rval && !same_type_p (r, rval)) 15574 { 15575 *result = NULL_TREE; 15576 return tbr_ambiguous_baseclass; 15577 } 15578 15579 rval = r; 15580 } 15581 } 15582 15583 *result = rval; 15584 return tbr_success; 15585 } 15586 15587 /* Returns the level of DECL, which declares a template parameter. */ 15588 15589 static int 15590 template_decl_level (tree decl) 15591 { 15592 switch (TREE_CODE (decl)) 15593 { 15594 case TYPE_DECL: 15595 case TEMPLATE_DECL: 15596 return TEMPLATE_TYPE_LEVEL (TREE_TYPE (decl)); 15597 15598 case PARM_DECL: 15599 return TEMPLATE_PARM_LEVEL (DECL_INITIAL (decl)); 15600 15601 default: 15602 gcc_unreachable (); 15603 } 15604 return 0; 15605 } 15606 15607 /* Decide whether ARG can be unified with PARM, considering only the 15608 cv-qualifiers of each type, given STRICT as documented for unify. 15609 Returns nonzero iff the unification is OK on that basis. */ 15610 15611 static int 15612 check_cv_quals_for_unify (int strict, tree arg, tree parm) 15613 { 15614 int arg_quals = cp_type_quals (arg); 15615 int parm_quals = cp_type_quals (parm); 15616 15617 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM 15618 && !(strict & UNIFY_ALLOW_OUTER_MORE_CV_QUAL)) 15619 { 15620 /* Although a CVR qualifier is ignored when being applied to a 15621 substituted template parameter ([8.3.2]/1 for example), that 15622 does not allow us to unify "const T" with "int&" because both 15623 types are not of the form "cv-list T" [14.8.2.5 temp.deduct.type]. 15624 It is ok when we're allowing additional CV qualifiers 15625 at the outer level [14.8.2.1]/3,1st bullet. */ 15626 if ((TREE_CODE (arg) == REFERENCE_TYPE 15627 || TREE_CODE (arg) == FUNCTION_TYPE 15628 || TREE_CODE (arg) == METHOD_TYPE) 15629 && (parm_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE))) 15630 return 0; 15631 15632 if ((!POINTER_TYPE_P (arg) && TREE_CODE (arg) != TEMPLATE_TYPE_PARM) 15633 && (parm_quals & TYPE_QUAL_RESTRICT)) 15634 return 0; 15635 } 15636 15637 if (!(strict & (UNIFY_ALLOW_MORE_CV_QUAL | UNIFY_ALLOW_OUTER_MORE_CV_QUAL)) 15638 && (arg_quals & parm_quals) != parm_quals) 15639 return 0; 15640 15641 if (!(strict & (UNIFY_ALLOW_LESS_CV_QUAL | UNIFY_ALLOW_OUTER_LESS_CV_QUAL)) 15642 && (parm_quals & arg_quals) != arg_quals) 15643 return 0; 15644 15645 return 1; 15646 } 15647 15648 /* Determines the LEVEL and INDEX for the template parameter PARM. */ 15649 void 15650 template_parm_level_and_index (tree parm, int* level, int* index) 15651 { 15652 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM 15653 || TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM 15654 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM) 15655 { 15656 *index = TEMPLATE_TYPE_IDX (parm); 15657 *level = TEMPLATE_TYPE_LEVEL (parm); 15658 } 15659 else 15660 { 15661 *index = TEMPLATE_PARM_IDX (parm); 15662 *level = TEMPLATE_PARM_LEVEL (parm); 15663 } 15664 } 15665 15666 #define RECUR_AND_CHECK_FAILURE(TP, TA, P, A, S, EP) \ 15667 do { \ 15668 if (unify (TP, TA, P, A, S, EP)) \ 15669 return 1; \ 15670 } while (0); 15671 15672 /* Unifies the remaining arguments in PACKED_ARGS with the pack 15673 expansion at the end of PACKED_PARMS. Returns 0 if the type 15674 deduction succeeds, 1 otherwise. STRICT is the same as in 15675 unify. CALL_ARGS_P is true iff PACKED_ARGS is actually a function 15676 call argument list. We'll need to adjust the arguments to make them 15677 types. SUBR tells us if this is from a recursive call to 15678 type_unification_real, or for comparing two template argument 15679 lists. */ 15680 15681 static int 15682 unify_pack_expansion (tree tparms, tree targs, tree packed_parms, 15683 tree packed_args, unification_kind_t strict, 15684 bool subr, bool explain_p) 15685 { 15686 tree parm 15687 = TREE_VEC_ELT (packed_parms, TREE_VEC_LENGTH (packed_parms) - 1); 15688 tree pattern = PACK_EXPANSION_PATTERN (parm); 15689 tree pack, packs = NULL_TREE; 15690 int i, start = TREE_VEC_LENGTH (packed_parms) - 1; 15691 int len = TREE_VEC_LENGTH (packed_args); 15692 15693 /* Determine the parameter packs we will be deducing from the 15694 pattern, and record their current deductions. */ 15695 for (pack = PACK_EXPANSION_PARAMETER_PACKS (parm); 15696 pack; pack = TREE_CHAIN (pack)) 15697 { 15698 tree parm_pack = TREE_VALUE (pack); 15699 int idx, level; 15700 15701 /* Determine the index and level of this parameter pack. */ 15702 template_parm_level_and_index (parm_pack, &level, &idx); 15703 15704 /* Keep track of the parameter packs and their corresponding 15705 argument packs. */ 15706 packs = tree_cons (parm_pack, TMPL_ARG (targs, level, idx), packs); 15707 TREE_TYPE (packs) = make_tree_vec (len - start); 15708 } 15709 15710 /* Loop through all of the arguments that have not yet been 15711 unified and unify each with the pattern. */ 15712 for (i = start; i < len; i++) 15713 { 15714 tree parm; 15715 bool any_explicit = false; 15716 tree arg = TREE_VEC_ELT (packed_args, i); 15717 15718 /* For each parameter pack, set its TMPL_ARG to either NULL_TREE 15719 or the element of its argument pack at the current index if 15720 this argument was explicitly specified. */ 15721 for (pack = packs; pack; pack = TREE_CHAIN (pack)) 15722 { 15723 int idx, level; 15724 tree arg, pargs; 15725 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx); 15726 15727 arg = NULL_TREE; 15728 if (TREE_VALUE (pack) 15729 && (pargs = ARGUMENT_PACK_EXPLICIT_ARGS (TREE_VALUE (pack))) 15730 && (i - start < TREE_VEC_LENGTH (pargs))) 15731 { 15732 any_explicit = true; 15733 arg = TREE_VEC_ELT (pargs, i - start); 15734 } 15735 TMPL_ARG (targs, level, idx) = arg; 15736 } 15737 15738 /* If we had explicit template arguments, substitute them into the 15739 pattern before deduction. */ 15740 if (any_explicit) 15741 { 15742 /* Some arguments might still be unspecified or dependent. */ 15743 bool dependent; 15744 ++processing_template_decl; 15745 dependent = any_dependent_template_arguments_p (targs); 15746 if (!dependent) 15747 --processing_template_decl; 15748 parm = tsubst (pattern, targs, 15749 explain_p ? tf_warning_or_error : tf_none, 15750 NULL_TREE); 15751 if (dependent) 15752 --processing_template_decl; 15753 if (parm == error_mark_node) 15754 return 1; 15755 } 15756 else 15757 parm = pattern; 15758 15759 /* Unify the pattern with the current argument. */ 15760 if (unify_one_argument (tparms, targs, parm, arg, subr, strict, 15761 LOOKUP_IMPLICIT, explain_p)) 15762 return 1; 15763 15764 /* For each parameter pack, collect the deduced value. */ 15765 for (pack = packs; pack; pack = TREE_CHAIN (pack)) 15766 { 15767 int idx, level; 15768 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx); 15769 15770 TREE_VEC_ELT (TREE_TYPE (pack), i - start) = 15771 TMPL_ARG (targs, level, idx); 15772 } 15773 } 15774 15775 /* Verify that the results of unification with the parameter packs 15776 produce results consistent with what we've seen before, and make 15777 the deduced argument packs available. */ 15778 for (pack = packs; pack; pack = TREE_CHAIN (pack)) 15779 { 15780 tree old_pack = TREE_VALUE (pack); 15781 tree new_args = TREE_TYPE (pack); 15782 int i, len = TREE_VEC_LENGTH (new_args); 15783 int idx, level; 15784 bool nondeduced_p = false; 15785 15786 /* By default keep the original deduced argument pack. 15787 If necessary, more specific code is going to update the 15788 resulting deduced argument later down in this function. */ 15789 template_parm_level_and_index (TREE_PURPOSE (pack), &level, &idx); 15790 TMPL_ARG (targs, level, idx) = old_pack; 15791 15792 /* If NEW_ARGS contains any NULL_TREE entries, we didn't 15793 actually deduce anything. */ 15794 for (i = 0; i < len && !nondeduced_p; ++i) 15795 if (TREE_VEC_ELT (new_args, i) == NULL_TREE) 15796 nondeduced_p = true; 15797 if (nondeduced_p) 15798 continue; 15799 15800 if (old_pack && ARGUMENT_PACK_INCOMPLETE_P (old_pack)) 15801 { 15802 /* If we had fewer function args than explicit template args, 15803 just use the explicits. */ 15804 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack); 15805 int explicit_len = TREE_VEC_LENGTH (explicit_args); 15806 if (len < explicit_len) 15807 new_args = explicit_args; 15808 } 15809 15810 if (!old_pack) 15811 { 15812 tree result; 15813 /* Build the deduced *_ARGUMENT_PACK. */ 15814 if (TREE_CODE (TREE_PURPOSE (pack)) == TEMPLATE_PARM_INDEX) 15815 { 15816 result = make_node (NONTYPE_ARGUMENT_PACK); 15817 TREE_TYPE (result) = 15818 TREE_TYPE (TEMPLATE_PARM_DECL (TREE_PURPOSE (pack))); 15819 TREE_CONSTANT (result) = 1; 15820 } 15821 else 15822 result = cxx_make_type (TYPE_ARGUMENT_PACK); 15823 15824 SET_ARGUMENT_PACK_ARGS (result, new_args); 15825 15826 /* Note the deduced argument packs for this parameter 15827 pack. */ 15828 TMPL_ARG (targs, level, idx) = result; 15829 } 15830 else if (ARGUMENT_PACK_INCOMPLETE_P (old_pack) 15831 && (ARGUMENT_PACK_ARGS (old_pack) 15832 == ARGUMENT_PACK_EXPLICIT_ARGS (old_pack))) 15833 { 15834 /* We only had the explicitly-provided arguments before, but 15835 now we have a complete set of arguments. */ 15836 tree explicit_args = ARGUMENT_PACK_EXPLICIT_ARGS (old_pack); 15837 15838 SET_ARGUMENT_PACK_ARGS (old_pack, new_args); 15839 ARGUMENT_PACK_INCOMPLETE_P (old_pack) = 1; 15840 ARGUMENT_PACK_EXPLICIT_ARGS (old_pack) = explicit_args; 15841 } 15842 else 15843 { 15844 tree bad_old_arg = NULL_TREE, bad_new_arg = NULL_TREE; 15845 tree old_args = ARGUMENT_PACK_ARGS (old_pack); 15846 15847 if (!comp_template_args_with_info (old_args, new_args, 15848 &bad_old_arg, &bad_new_arg)) 15849 /* Inconsistent unification of this parameter pack. */ 15850 return unify_parameter_pack_inconsistent (explain_p, 15851 bad_old_arg, 15852 bad_new_arg); 15853 } 15854 } 15855 15856 return unify_success (explain_p); 15857 } 15858 15859 /* Deduce the value of template parameters. TPARMS is the (innermost) 15860 set of template parameters to a template. TARGS is the bindings 15861 for those template parameters, as determined thus far; TARGS may 15862 include template arguments for outer levels of template parameters 15863 as well. PARM is a parameter to a template function, or a 15864 subcomponent of that parameter; ARG is the corresponding argument. 15865 This function attempts to match PARM with ARG in a manner 15866 consistent with the existing assignments in TARGS. If more values 15867 are deduced, then TARGS is updated. 15868 15869 Returns 0 if the type deduction succeeds, 1 otherwise. The 15870 parameter STRICT is a bitwise or of the following flags: 15871 15872 UNIFY_ALLOW_NONE: 15873 Require an exact match between PARM and ARG. 15874 UNIFY_ALLOW_MORE_CV_QUAL: 15875 Allow the deduced ARG to be more cv-qualified (by qualification 15876 conversion) than ARG. 15877 UNIFY_ALLOW_LESS_CV_QUAL: 15878 Allow the deduced ARG to be less cv-qualified than ARG. 15879 UNIFY_ALLOW_DERIVED: 15880 Allow the deduced ARG to be a template base class of ARG, 15881 or a pointer to a template base class of the type pointed to by 15882 ARG. 15883 UNIFY_ALLOW_INTEGER: 15884 Allow any integral type to be deduced. See the TEMPLATE_PARM_INDEX 15885 case for more information. 15886 UNIFY_ALLOW_OUTER_LEVEL: 15887 This is the outermost level of a deduction. Used to determine validity 15888 of qualification conversions. A valid qualification conversion must 15889 have const qualified pointers leading up to the inner type which 15890 requires additional CV quals, except at the outer level, where const 15891 is not required [conv.qual]. It would be normal to set this flag in 15892 addition to setting UNIFY_ALLOW_MORE_CV_QUAL. 15893 UNIFY_ALLOW_OUTER_MORE_CV_QUAL: 15894 This is the outermost level of a deduction, and PARM can be more CV 15895 qualified at this point. 15896 UNIFY_ALLOW_OUTER_LESS_CV_QUAL: 15897 This is the outermost level of a deduction, and PARM can be less CV 15898 qualified at this point. */ 15899 15900 static int 15901 unify (tree tparms, tree targs, tree parm, tree arg, int strict, 15902 bool explain_p) 15903 { 15904 int idx; 15905 tree targ; 15906 tree tparm; 15907 int strict_in = strict; 15908 15909 /* I don't think this will do the right thing with respect to types. 15910 But the only case I've seen it in so far has been array bounds, where 15911 signedness is the only information lost, and I think that will be 15912 okay. */ 15913 while (TREE_CODE (parm) == NOP_EXPR) 15914 parm = TREE_OPERAND (parm, 0); 15915 15916 if (arg == error_mark_node) 15917 return unify_invalid (explain_p); 15918 if (arg == unknown_type_node 15919 || arg == init_list_type_node) 15920 /* We can't deduce anything from this, but we might get all the 15921 template args from other function args. */ 15922 return unify_success (explain_p); 15923 15924 /* If PARM uses template parameters, then we can't bail out here, 15925 even if ARG == PARM, since we won't record unifications for the 15926 template parameters. We might need them if we're trying to 15927 figure out which of two things is more specialized. */ 15928 if (arg == parm && !uses_template_parms (parm)) 15929 return unify_success (explain_p); 15930 15931 /* Handle init lists early, so the rest of the function can assume 15932 we're dealing with a type. */ 15933 if (BRACE_ENCLOSED_INITIALIZER_P (arg)) 15934 { 15935 tree elt, elttype; 15936 unsigned i; 15937 tree orig_parm = parm; 15938 15939 /* Replace T with std::initializer_list<T> for deduction. */ 15940 if (TREE_CODE (parm) == TEMPLATE_TYPE_PARM 15941 && flag_deduce_init_list) 15942 parm = listify (parm); 15943 15944 if (!is_std_init_list (parm)) 15945 /* We can only deduce from an initializer list argument if the 15946 parameter is std::initializer_list; otherwise this is a 15947 non-deduced context. */ 15948 return unify_success (explain_p); 15949 15950 elttype = TREE_VEC_ELT (CLASSTYPE_TI_ARGS (parm), 0); 15951 15952 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (arg), i, elt) 15953 { 15954 int elt_strict = strict; 15955 15956 if (elt == error_mark_node) 15957 return unify_invalid (explain_p); 15958 15959 if (!BRACE_ENCLOSED_INITIALIZER_P (elt)) 15960 { 15961 tree type = TREE_TYPE (elt); 15962 /* It should only be possible to get here for a call. */ 15963 gcc_assert (elt_strict & UNIFY_ALLOW_OUTER_LEVEL); 15964 elt_strict |= maybe_adjust_types_for_deduction 15965 (DEDUCE_CALL, &elttype, &type, elt); 15966 elt = type; 15967 } 15968 15969 RECUR_AND_CHECK_FAILURE (tparms, targs, elttype, elt, elt_strict, 15970 explain_p); 15971 } 15972 15973 /* If the std::initializer_list<T> deduction worked, replace the 15974 deduced A with std::initializer_list<A>. */ 15975 if (orig_parm != parm) 15976 { 15977 idx = TEMPLATE_TYPE_IDX (orig_parm); 15978 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx); 15979 targ = listify (targ); 15980 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = targ; 15981 } 15982 return unify_success (explain_p); 15983 } 15984 15985 /* Immediately reject some pairs that won't unify because of 15986 cv-qualification mismatches. */ 15987 if (TREE_CODE (arg) == TREE_CODE (parm) 15988 && TYPE_P (arg) 15989 /* It is the elements of the array which hold the cv quals of an array 15990 type, and the elements might be template type parms. We'll check 15991 when we recurse. */ 15992 && TREE_CODE (arg) != ARRAY_TYPE 15993 /* We check the cv-qualifiers when unifying with template type 15994 parameters below. We want to allow ARG `const T' to unify with 15995 PARM `T' for example, when computing which of two templates 15996 is more specialized, for example. */ 15997 && TREE_CODE (arg) != TEMPLATE_TYPE_PARM 15998 && !check_cv_quals_for_unify (strict_in, arg, parm)) 15999 return unify_cv_qual_mismatch (explain_p, parm, arg); 16000 16001 if (!(strict & UNIFY_ALLOW_OUTER_LEVEL) 16002 && TYPE_P (parm) && !CP_TYPE_CONST_P (parm)) 16003 strict &= ~UNIFY_ALLOW_MORE_CV_QUAL; 16004 strict &= ~UNIFY_ALLOW_OUTER_LEVEL; 16005 strict &= ~UNIFY_ALLOW_DERIVED; 16006 strict &= ~UNIFY_ALLOW_OUTER_MORE_CV_QUAL; 16007 strict &= ~UNIFY_ALLOW_OUTER_LESS_CV_QUAL; 16008 16009 switch (TREE_CODE (parm)) 16010 { 16011 case TYPENAME_TYPE: 16012 case SCOPE_REF: 16013 case UNBOUND_CLASS_TEMPLATE: 16014 /* In a type which contains a nested-name-specifier, template 16015 argument values cannot be deduced for template parameters used 16016 within the nested-name-specifier. */ 16017 return unify_success (explain_p); 16018 16019 case TEMPLATE_TYPE_PARM: 16020 case TEMPLATE_TEMPLATE_PARM: 16021 case BOUND_TEMPLATE_TEMPLATE_PARM: 16022 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0)); 16023 if (tparm == error_mark_node) 16024 return unify_invalid (explain_p); 16025 16026 if (TEMPLATE_TYPE_LEVEL (parm) 16027 != template_decl_level (tparm)) 16028 /* The PARM is not one we're trying to unify. Just check 16029 to see if it matches ARG. */ 16030 { 16031 if (TREE_CODE (arg) == TREE_CODE (parm) 16032 && same_type_p (parm, arg)) 16033 return unify_success (explain_p); 16034 else 16035 return unify_type_mismatch (explain_p, parm, arg); 16036 } 16037 idx = TEMPLATE_TYPE_IDX (parm); 16038 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx); 16039 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, idx)); 16040 if (tparm == error_mark_node) 16041 return unify_invalid (explain_p); 16042 16043 /* Check for mixed types and values. */ 16044 if ((TREE_CODE (parm) == TEMPLATE_TYPE_PARM 16045 && TREE_CODE (tparm) != TYPE_DECL) 16046 || (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM 16047 && TREE_CODE (tparm) != TEMPLATE_DECL)) 16048 gcc_unreachable (); 16049 16050 if (TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM) 16051 { 16052 /* ARG must be constructed from a template class or a template 16053 template parameter. */ 16054 if (TREE_CODE (arg) != BOUND_TEMPLATE_TEMPLATE_PARM 16055 && !CLASSTYPE_SPECIALIZATION_OF_PRIMARY_TEMPLATE_P (arg)) 16056 return unify_template_deduction_failure (explain_p, parm, arg); 16057 16058 { 16059 tree parmvec = TYPE_TI_ARGS (parm); 16060 tree argvec = INNERMOST_TEMPLATE_ARGS (TYPE_TI_ARGS (arg)); 16061 tree full_argvec = add_to_template_args (targs, argvec); 16062 tree parm_parms 16063 = DECL_INNERMOST_TEMPLATE_PARMS 16064 (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (parm)); 16065 int i, len; 16066 int parm_variadic_p = 0; 16067 16068 /* The resolution to DR150 makes clear that default 16069 arguments for an N-argument may not be used to bind T 16070 to a template template parameter with fewer than N 16071 parameters. It is not safe to permit the binding of 16072 default arguments as an extension, as that may change 16073 the meaning of a conforming program. Consider: 16074 16075 struct Dense { static const unsigned int dim = 1; }; 16076 16077 template <template <typename> class View, 16078 typename Block> 16079 void operator+(float, View<Block> const&); 16080 16081 template <typename Block, 16082 unsigned int Dim = Block::dim> 16083 struct Lvalue_proxy { operator float() const; }; 16084 16085 void 16086 test_1d (void) { 16087 Lvalue_proxy<Dense> p; 16088 float b; 16089 b + p; 16090 } 16091 16092 Here, if Lvalue_proxy is permitted to bind to View, then 16093 the global operator+ will be used; if they are not, the 16094 Lvalue_proxy will be converted to float. */ 16095 if (coerce_template_parms (parm_parms, 16096 full_argvec, 16097 TYPE_TI_TEMPLATE (parm), 16098 (explain_p 16099 ? tf_warning_or_error 16100 : tf_none), 16101 /*require_all_args=*/true, 16102 /*use_default_args=*/false) 16103 == error_mark_node) 16104 return 1; 16105 16106 /* Deduce arguments T, i from TT<T> or TT<i>. 16107 We check each element of PARMVEC and ARGVEC individually 16108 rather than the whole TREE_VEC since they can have 16109 different number of elements. */ 16110 16111 parmvec = expand_template_argument_pack (parmvec); 16112 argvec = expand_template_argument_pack (argvec); 16113 16114 len = TREE_VEC_LENGTH (parmvec); 16115 16116 /* Check if the parameters end in a pack, making them 16117 variadic. */ 16118 if (len > 0 16119 && PACK_EXPANSION_P (TREE_VEC_ELT (parmvec, len - 1))) 16120 parm_variadic_p = 1; 16121 16122 if (TREE_VEC_LENGTH (argvec) < len - parm_variadic_p) 16123 return unify_too_few_arguments (explain_p, 16124 TREE_VEC_LENGTH (argvec), len); 16125 16126 for (i = 0; i < len - parm_variadic_p; ++i) 16127 { 16128 RECUR_AND_CHECK_FAILURE (tparms, targs, 16129 TREE_VEC_ELT (parmvec, i), 16130 TREE_VEC_ELT (argvec, i), 16131 UNIFY_ALLOW_NONE, explain_p); 16132 } 16133 16134 if (parm_variadic_p 16135 && unify_pack_expansion (tparms, targs, 16136 parmvec, argvec, 16137 DEDUCE_EXACT, 16138 /*subr=*/true, explain_p)) 16139 return 1; 16140 } 16141 arg = TYPE_TI_TEMPLATE (arg); 16142 16143 /* Fall through to deduce template name. */ 16144 } 16145 16146 if (TREE_CODE (parm) == TEMPLATE_TEMPLATE_PARM 16147 || TREE_CODE (parm) == BOUND_TEMPLATE_TEMPLATE_PARM) 16148 { 16149 /* Deduce template name TT from TT, TT<>, TT<T> and TT<i>. */ 16150 16151 /* Simple cases: Value already set, does match or doesn't. */ 16152 if (targ != NULL_TREE && template_args_equal (targ, arg)) 16153 return unify_success (explain_p); 16154 else if (targ) 16155 return unify_inconsistency (explain_p, parm, targ, arg); 16156 } 16157 else 16158 { 16159 /* If PARM is `const T' and ARG is only `int', we don't have 16160 a match unless we are allowing additional qualification. 16161 If ARG is `const int' and PARM is just `T' that's OK; 16162 that binds `const int' to `T'. */ 16163 if (!check_cv_quals_for_unify (strict_in | UNIFY_ALLOW_LESS_CV_QUAL, 16164 arg, parm)) 16165 return unify_cv_qual_mismatch (explain_p, parm, arg); 16166 16167 /* Consider the case where ARG is `const volatile int' and 16168 PARM is `const T'. Then, T should be `volatile int'. */ 16169 arg = cp_build_qualified_type_real 16170 (arg, cp_type_quals (arg) & ~cp_type_quals (parm), tf_none); 16171 if (arg == error_mark_node) 16172 return unify_invalid (explain_p); 16173 16174 /* Simple cases: Value already set, does match or doesn't. */ 16175 if (targ != NULL_TREE && same_type_p (targ, arg)) 16176 return unify_success (explain_p); 16177 else if (targ) 16178 return unify_inconsistency (explain_p, parm, targ, arg); 16179 16180 /* Make sure that ARG is not a variable-sized array. (Note 16181 that were talking about variable-sized arrays (like 16182 `int[n]'), rather than arrays of unknown size (like 16183 `int[]').) We'll get very confused by such a type since 16184 the bound of the array is not constant, and therefore 16185 not mangleable. Besides, such types are not allowed in 16186 ISO C++, so we can do as we please here. We do allow 16187 them for 'auto' deduction, since that isn't ABI-exposed. */ 16188 if (!is_auto (parm) && variably_modified_type_p (arg, NULL_TREE)) 16189 return unify_vla_arg (explain_p, arg); 16190 16191 /* Strip typedefs as in convert_template_argument. */ 16192 arg = canonicalize_type_argument (arg, tf_none); 16193 } 16194 16195 /* If ARG is a parameter pack or an expansion, we cannot unify 16196 against it unless PARM is also a parameter pack. */ 16197 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg)) 16198 && !template_parameter_pack_p (parm)) 16199 return unify_parameter_pack_mismatch (explain_p, parm, arg); 16200 16201 /* If the argument deduction results is a METHOD_TYPE, 16202 then there is a problem. 16203 METHOD_TYPE doesn't map to any real C++ type the result of 16204 the deduction can not be of that type. */ 16205 if (TREE_CODE (arg) == METHOD_TYPE) 16206 return unify_method_type_error (explain_p, arg); 16207 16208 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg; 16209 return unify_success (explain_p); 16210 16211 case TEMPLATE_PARM_INDEX: 16212 tparm = TREE_VALUE (TREE_VEC_ELT (tparms, 0)); 16213 if (tparm == error_mark_node) 16214 return unify_invalid (explain_p); 16215 16216 if (TEMPLATE_PARM_LEVEL (parm) 16217 != template_decl_level (tparm)) 16218 { 16219 /* The PARM is not one we're trying to unify. Just check 16220 to see if it matches ARG. */ 16221 int result = !(TREE_CODE (arg) == TREE_CODE (parm) 16222 && cp_tree_equal (parm, arg)); 16223 if (result) 16224 unify_expression_unequal (explain_p, parm, arg); 16225 return result; 16226 } 16227 16228 idx = TEMPLATE_PARM_IDX (parm); 16229 targ = TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx); 16230 16231 if (targ) 16232 { 16233 int x = !cp_tree_equal (targ, arg); 16234 if (x) 16235 unify_inconsistency (explain_p, parm, targ, arg); 16236 return x; 16237 } 16238 16239 /* [temp.deduct.type] If, in the declaration of a function template 16240 with a non-type template-parameter, the non-type 16241 template-parameter is used in an expression in the function 16242 parameter-list and, if the corresponding template-argument is 16243 deduced, the template-argument type shall match the type of the 16244 template-parameter exactly, except that a template-argument 16245 deduced from an array bound may be of any integral type. 16246 The non-type parameter might use already deduced type parameters. */ 16247 tparm = tsubst (TREE_TYPE (parm), targs, 0, NULL_TREE); 16248 if (!TREE_TYPE (arg)) 16249 /* Template-parameter dependent expression. Just accept it for now. 16250 It will later be processed in convert_template_argument. */ 16251 ; 16252 else if (same_type_p (TREE_TYPE (arg), tparm)) 16253 /* OK */; 16254 else if ((strict & UNIFY_ALLOW_INTEGER) 16255 && (TREE_CODE (tparm) == INTEGER_TYPE 16256 || TREE_CODE (tparm) == BOOLEAN_TYPE)) 16257 /* Convert the ARG to the type of PARM; the deduced non-type 16258 template argument must exactly match the types of the 16259 corresponding parameter. */ 16260 arg = fold (build_nop (tparm, arg)); 16261 else if (uses_template_parms (tparm)) 16262 /* We haven't deduced the type of this parameter yet. Try again 16263 later. */ 16264 return unify_success (explain_p); 16265 else 16266 return unify_type_mismatch (explain_p, tparm, arg); 16267 16268 /* If ARG is a parameter pack or an expansion, we cannot unify 16269 against it unless PARM is also a parameter pack. */ 16270 if ((template_parameter_pack_p (arg) || PACK_EXPANSION_P (arg)) 16271 && !TEMPLATE_PARM_PARAMETER_PACK (parm)) 16272 return unify_parameter_pack_mismatch (explain_p, parm, arg); 16273 16274 arg = strip_typedefs_expr (arg); 16275 TREE_VEC_ELT (INNERMOST_TEMPLATE_ARGS (targs), idx) = arg; 16276 return unify_success (explain_p); 16277 16278 case PTRMEM_CST: 16279 { 16280 /* A pointer-to-member constant can be unified only with 16281 another constant. */ 16282 if (TREE_CODE (arg) != PTRMEM_CST) 16283 return unify_ptrmem_cst_mismatch (explain_p, parm, arg); 16284 16285 /* Just unify the class member. It would be useless (and possibly 16286 wrong, depending on the strict flags) to unify also 16287 PTRMEM_CST_CLASS, because we want to be sure that both parm and 16288 arg refer to the same variable, even if through different 16289 classes. For instance: 16290 16291 struct A { int x; }; 16292 struct B : A { }; 16293 16294 Unification of &A::x and &B::x must succeed. */ 16295 return unify (tparms, targs, PTRMEM_CST_MEMBER (parm), 16296 PTRMEM_CST_MEMBER (arg), strict, explain_p); 16297 } 16298 16299 case POINTER_TYPE: 16300 { 16301 if (TREE_CODE (arg) != POINTER_TYPE) 16302 return unify_type_mismatch (explain_p, parm, arg); 16303 16304 /* [temp.deduct.call] 16305 16306 A can be another pointer or pointer to member type that can 16307 be converted to the deduced A via a qualification 16308 conversion (_conv.qual_). 16309 16310 We pass down STRICT here rather than UNIFY_ALLOW_NONE. 16311 This will allow for additional cv-qualification of the 16312 pointed-to types if appropriate. */ 16313 16314 if (TREE_CODE (TREE_TYPE (arg)) == RECORD_TYPE) 16315 /* The derived-to-base conversion only persists through one 16316 level of pointers. */ 16317 strict |= (strict_in & UNIFY_ALLOW_DERIVED); 16318 16319 return unify (tparms, targs, TREE_TYPE (parm), 16320 TREE_TYPE (arg), strict, explain_p); 16321 } 16322 16323 case REFERENCE_TYPE: 16324 if (TREE_CODE (arg) != REFERENCE_TYPE) 16325 return unify_type_mismatch (explain_p, parm, arg); 16326 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg), 16327 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p); 16328 16329 case ARRAY_TYPE: 16330 if (TREE_CODE (arg) != ARRAY_TYPE) 16331 return unify_type_mismatch (explain_p, parm, arg); 16332 if ((TYPE_DOMAIN (parm) == NULL_TREE) 16333 != (TYPE_DOMAIN (arg) == NULL_TREE)) 16334 return unify_type_mismatch (explain_p, parm, arg); 16335 if (TYPE_DOMAIN (parm) != NULL_TREE) 16336 { 16337 tree parm_max; 16338 tree arg_max; 16339 bool parm_cst; 16340 bool arg_cst; 16341 16342 /* Our representation of array types uses "N - 1" as the 16343 TYPE_MAX_VALUE for an array with "N" elements, if "N" is 16344 not an integer constant. We cannot unify arbitrarily 16345 complex expressions, so we eliminate the MINUS_EXPRs 16346 here. */ 16347 parm_max = TYPE_MAX_VALUE (TYPE_DOMAIN (parm)); 16348 parm_cst = TREE_CODE (parm_max) == INTEGER_CST; 16349 if (!parm_cst) 16350 { 16351 gcc_assert (TREE_CODE (parm_max) == MINUS_EXPR); 16352 parm_max = TREE_OPERAND (parm_max, 0); 16353 } 16354 arg_max = TYPE_MAX_VALUE (TYPE_DOMAIN (arg)); 16355 arg_cst = TREE_CODE (arg_max) == INTEGER_CST; 16356 if (!arg_cst) 16357 { 16358 /* The ARG_MAX may not be a simple MINUS_EXPR, if we are 16359 trying to unify the type of a variable with the type 16360 of a template parameter. For example: 16361 16362 template <unsigned int N> 16363 void f (char (&) [N]); 16364 int g(); 16365 void h(int i) { 16366 char a[g(i)]; 16367 f(a); 16368 } 16369 16370 Here, the type of the ARG will be "int [g(i)]", and 16371 may be a SAVE_EXPR, etc. */ 16372 if (TREE_CODE (arg_max) != MINUS_EXPR) 16373 return unify_vla_arg (explain_p, arg); 16374 arg_max = TREE_OPERAND (arg_max, 0); 16375 } 16376 16377 /* If only one of the bounds used a MINUS_EXPR, compensate 16378 by adding one to the other bound. */ 16379 if (parm_cst && !arg_cst) 16380 parm_max = fold_build2_loc (input_location, PLUS_EXPR, 16381 integer_type_node, 16382 parm_max, 16383 integer_one_node); 16384 else if (arg_cst && !parm_cst) 16385 arg_max = fold_build2_loc (input_location, PLUS_EXPR, 16386 integer_type_node, 16387 arg_max, 16388 integer_one_node); 16389 16390 RECUR_AND_CHECK_FAILURE (tparms, targs, parm_max, arg_max, 16391 UNIFY_ALLOW_INTEGER, explain_p); 16392 } 16393 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg), 16394 strict & UNIFY_ALLOW_MORE_CV_QUAL, explain_p); 16395 16396 case REAL_TYPE: 16397 case COMPLEX_TYPE: 16398 case VECTOR_TYPE: 16399 case INTEGER_TYPE: 16400 case BOOLEAN_TYPE: 16401 case ENUMERAL_TYPE: 16402 case VOID_TYPE: 16403 case NULLPTR_TYPE: 16404 if (TREE_CODE (arg) != TREE_CODE (parm)) 16405 return unify_type_mismatch (explain_p, parm, arg); 16406 16407 /* We have already checked cv-qualification at the top of the 16408 function. */ 16409 if (!same_type_ignoring_top_level_qualifiers_p (arg, parm)) 16410 return unify_type_mismatch (explain_p, parm, arg); 16411 16412 /* As far as unification is concerned, this wins. Later checks 16413 will invalidate it if necessary. */ 16414 return unify_success (explain_p); 16415 16416 /* Types INTEGER_CST and MINUS_EXPR can come from array bounds. */ 16417 /* Type INTEGER_CST can come from ordinary constant template args. */ 16418 case INTEGER_CST: 16419 while (TREE_CODE (arg) == NOP_EXPR) 16420 arg = TREE_OPERAND (arg, 0); 16421 16422 if (TREE_CODE (arg) != INTEGER_CST) 16423 return unify_template_argument_mismatch (explain_p, parm, arg); 16424 return (tree_int_cst_equal (parm, arg) 16425 ? unify_success (explain_p) 16426 : unify_template_argument_mismatch (explain_p, parm, arg)); 16427 16428 case TREE_VEC: 16429 { 16430 int i, len, argslen; 16431 int parm_variadic_p = 0; 16432 16433 if (TREE_CODE (arg) != TREE_VEC) 16434 return unify_template_argument_mismatch (explain_p, parm, arg); 16435 16436 len = TREE_VEC_LENGTH (parm); 16437 argslen = TREE_VEC_LENGTH (arg); 16438 16439 /* Check for pack expansions in the parameters. */ 16440 for (i = 0; i < len; ++i) 16441 { 16442 if (PACK_EXPANSION_P (TREE_VEC_ELT (parm, i))) 16443 { 16444 if (i == len - 1) 16445 /* We can unify against something with a trailing 16446 parameter pack. */ 16447 parm_variadic_p = 1; 16448 else 16449 /* [temp.deduct.type]/9: If the template argument list of 16450 P contains a pack expansion that is not the last 16451 template argument, the entire template argument list 16452 is a non-deduced context. */ 16453 return unify_success (explain_p); 16454 } 16455 } 16456 16457 /* If we don't have enough arguments to satisfy the parameters 16458 (not counting the pack expression at the end), or we have 16459 too many arguments for a parameter list that doesn't end in 16460 a pack expression, we can't unify. */ 16461 if (parm_variadic_p 16462 ? argslen < len - parm_variadic_p 16463 : argslen != len) 16464 return unify_arity (explain_p, TREE_VEC_LENGTH (arg), len); 16465 16466 /* Unify all of the parameters that precede the (optional) 16467 pack expression. */ 16468 for (i = 0; i < len - parm_variadic_p; ++i) 16469 { 16470 RECUR_AND_CHECK_FAILURE (tparms, targs, 16471 TREE_VEC_ELT (parm, i), 16472 TREE_VEC_ELT (arg, i), 16473 UNIFY_ALLOW_NONE, explain_p); 16474 } 16475 if (parm_variadic_p) 16476 return unify_pack_expansion (tparms, targs, parm, arg, 16477 DEDUCE_EXACT, 16478 /*subr=*/true, explain_p); 16479 return unify_success (explain_p); 16480 } 16481 16482 case RECORD_TYPE: 16483 case UNION_TYPE: 16484 if (TREE_CODE (arg) != TREE_CODE (parm)) 16485 return unify_type_mismatch (explain_p, parm, arg); 16486 16487 if (TYPE_PTRMEMFUNC_P (parm)) 16488 { 16489 if (!TYPE_PTRMEMFUNC_P (arg)) 16490 return unify_type_mismatch (explain_p, parm, arg); 16491 16492 return unify (tparms, targs, 16493 TYPE_PTRMEMFUNC_FN_TYPE (parm), 16494 TYPE_PTRMEMFUNC_FN_TYPE (arg), 16495 strict, explain_p); 16496 } 16497 16498 if (CLASSTYPE_TEMPLATE_INFO (parm)) 16499 { 16500 tree t = NULL_TREE; 16501 16502 if (strict_in & UNIFY_ALLOW_DERIVED) 16503 { 16504 /* First, we try to unify the PARM and ARG directly. */ 16505 t = try_class_unification (tparms, targs, 16506 parm, arg, explain_p); 16507 16508 if (!t) 16509 { 16510 /* Fallback to the special case allowed in 16511 [temp.deduct.call]: 16512 16513 If P is a class, and P has the form 16514 template-id, then A can be a derived class of 16515 the deduced A. Likewise, if P is a pointer to 16516 a class of the form template-id, A can be a 16517 pointer to a derived class pointed to by the 16518 deduced A. */ 16519 enum template_base_result r; 16520 r = get_template_base (tparms, targs, parm, arg, 16521 explain_p, &t); 16522 16523 if (!t) 16524 return unify_no_common_base (explain_p, r, parm, arg); 16525 } 16526 } 16527 else if (CLASSTYPE_TEMPLATE_INFO (arg) 16528 && (CLASSTYPE_TI_TEMPLATE (parm) 16529 == CLASSTYPE_TI_TEMPLATE (arg))) 16530 /* Perhaps PARM is something like S<U> and ARG is S<int>. 16531 Then, we should unify `int' and `U'. */ 16532 t = arg; 16533 else 16534 /* There's no chance of unification succeeding. */ 16535 return unify_type_mismatch (explain_p, parm, arg); 16536 16537 return unify (tparms, targs, CLASSTYPE_TI_ARGS (parm), 16538 CLASSTYPE_TI_ARGS (t), UNIFY_ALLOW_NONE, explain_p); 16539 } 16540 else if (!same_type_ignoring_top_level_qualifiers_p (parm, arg)) 16541 return unify_type_mismatch (explain_p, parm, arg); 16542 return unify_success (explain_p); 16543 16544 case METHOD_TYPE: 16545 case FUNCTION_TYPE: 16546 { 16547 unsigned int nargs; 16548 tree *args; 16549 tree a; 16550 unsigned int i; 16551 16552 if (TREE_CODE (arg) != TREE_CODE (parm)) 16553 return unify_type_mismatch (explain_p, parm, arg); 16554 16555 /* CV qualifications for methods can never be deduced, they must 16556 match exactly. We need to check them explicitly here, 16557 because type_unification_real treats them as any other 16558 cv-qualified parameter. */ 16559 if (TREE_CODE (parm) == METHOD_TYPE 16560 && (!check_cv_quals_for_unify 16561 (UNIFY_ALLOW_NONE, 16562 class_of_this_parm (arg), 16563 class_of_this_parm (parm)))) 16564 return unify_cv_qual_mismatch (explain_p, parm, arg); 16565 16566 RECUR_AND_CHECK_FAILURE (tparms, targs, TREE_TYPE (parm), 16567 TREE_TYPE (arg), UNIFY_ALLOW_NONE, explain_p); 16568 16569 nargs = list_length (TYPE_ARG_TYPES (arg)); 16570 args = XALLOCAVEC (tree, nargs); 16571 for (a = TYPE_ARG_TYPES (arg), i = 0; 16572 a != NULL_TREE && a != void_list_node; 16573 a = TREE_CHAIN (a), ++i) 16574 args[i] = TREE_VALUE (a); 16575 nargs = i; 16576 16577 return type_unification_real (tparms, targs, TYPE_ARG_TYPES (parm), 16578 args, nargs, 1, DEDUCE_EXACT, 16579 LOOKUP_NORMAL, explain_p); 16580 } 16581 16582 case OFFSET_TYPE: 16583 /* Unify a pointer to member with a pointer to member function, which 16584 deduces the type of the member as a function type. */ 16585 if (TYPE_PTRMEMFUNC_P (arg)) 16586 { 16587 tree method_type; 16588 tree fntype; 16589 16590 /* Check top-level cv qualifiers */ 16591 if (!check_cv_quals_for_unify (UNIFY_ALLOW_NONE, arg, parm)) 16592 return unify_cv_qual_mismatch (explain_p, parm, arg); 16593 16594 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm), 16595 TYPE_PTRMEMFUNC_OBJECT_TYPE (arg), 16596 UNIFY_ALLOW_NONE, explain_p); 16597 16598 /* Determine the type of the function we are unifying against. */ 16599 method_type = TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (arg)); 16600 fntype = 16601 build_function_type (TREE_TYPE (method_type), 16602 TREE_CHAIN (TYPE_ARG_TYPES (method_type))); 16603 16604 /* Extract the cv-qualifiers of the member function from the 16605 implicit object parameter and place them on the function 16606 type to be restored later. */ 16607 fntype = apply_memfn_quals (fntype, type_memfn_quals (method_type)); 16608 return unify (tparms, targs, TREE_TYPE (parm), fntype, strict, explain_p); 16609 } 16610 16611 if (TREE_CODE (arg) != OFFSET_TYPE) 16612 return unify_type_mismatch (explain_p, parm, arg); 16613 RECUR_AND_CHECK_FAILURE (tparms, targs, TYPE_OFFSET_BASETYPE (parm), 16614 TYPE_OFFSET_BASETYPE (arg), 16615 UNIFY_ALLOW_NONE, explain_p); 16616 return unify (tparms, targs, TREE_TYPE (parm), TREE_TYPE (arg), 16617 strict, explain_p); 16618 16619 case CONST_DECL: 16620 if (DECL_TEMPLATE_PARM_P (parm)) 16621 return unify (tparms, targs, DECL_INITIAL (parm), arg, strict, explain_p); 16622 if (arg != integral_constant_value (parm)) 16623 return unify_template_argument_mismatch (explain_p, parm, arg); 16624 return unify_success (explain_p); 16625 16626 case FIELD_DECL: 16627 case TEMPLATE_DECL: 16628 /* Matched cases are handled by the ARG == PARM test above. */ 16629 return unify_template_argument_mismatch (explain_p, parm, arg); 16630 16631 case VAR_DECL: 16632 /* A non-type template parameter that is a variable should be a 16633 an integral constant, in which case, it whould have been 16634 folded into its (constant) value. So we should not be getting 16635 a variable here. */ 16636 gcc_unreachable (); 16637 16638 case TYPE_ARGUMENT_PACK: 16639 case NONTYPE_ARGUMENT_PACK: 16640 return unify (tparms, targs, ARGUMENT_PACK_ARGS (parm), 16641 ARGUMENT_PACK_ARGS (arg), strict, explain_p); 16642 16643 case TYPEOF_TYPE: 16644 case DECLTYPE_TYPE: 16645 case UNDERLYING_TYPE: 16646 /* Cannot deduce anything from TYPEOF_TYPE, DECLTYPE_TYPE, 16647 or UNDERLYING_TYPE nodes. */ 16648 return unify_success (explain_p); 16649 16650 case ERROR_MARK: 16651 /* Unification fails if we hit an error node. */ 16652 return unify_invalid (explain_p); 16653 16654 default: 16655 /* An unresolved overload is a nondeduced context. */ 16656 if (is_overloaded_fn (parm) || type_unknown_p (parm)) 16657 return unify_success (explain_p); 16658 gcc_assert (EXPR_P (parm)); 16659 16660 /* We must be looking at an expression. This can happen with 16661 something like: 16662 16663 template <int I> 16664 void foo(S<I>, S<I + 2>); 16665 16666 This is a "nondeduced context": 16667 16668 [deduct.type] 16669 16670 The nondeduced contexts are: 16671 16672 --A type that is a template-id in which one or more of 16673 the template-arguments is an expression that references 16674 a template-parameter. 16675 16676 In these cases, we assume deduction succeeded, but don't 16677 actually infer any unifications. */ 16678 16679 if (!uses_template_parms (parm) 16680 && !template_args_equal (parm, arg)) 16681 return unify_expression_unequal (explain_p, parm, arg); 16682 else 16683 return unify_success (explain_p); 16684 } 16685 } 16686 #undef RECUR_AND_CHECK_FAILURE 16687 16688 /* Note that DECL can be defined in this translation unit, if 16689 required. */ 16690 16691 static void 16692 mark_definable (tree decl) 16693 { 16694 tree clone; 16695 DECL_NOT_REALLY_EXTERN (decl) = 1; 16696 FOR_EACH_CLONE (clone, decl) 16697 DECL_NOT_REALLY_EXTERN (clone) = 1; 16698 } 16699 16700 /* Called if RESULT is explicitly instantiated, or is a member of an 16701 explicitly instantiated class. */ 16702 16703 void 16704 mark_decl_instantiated (tree result, int extern_p) 16705 { 16706 SET_DECL_EXPLICIT_INSTANTIATION (result); 16707 16708 /* If this entity has already been written out, it's too late to 16709 make any modifications. */ 16710 if (TREE_ASM_WRITTEN (result)) 16711 return; 16712 16713 if (TREE_CODE (result) != FUNCTION_DECL) 16714 /* The TREE_PUBLIC flag for function declarations will have been 16715 set correctly by tsubst. */ 16716 TREE_PUBLIC (result) = 1; 16717 16718 /* This might have been set by an earlier implicit instantiation. */ 16719 DECL_COMDAT (result) = 0; 16720 16721 if (extern_p) 16722 DECL_NOT_REALLY_EXTERN (result) = 0; 16723 else 16724 { 16725 mark_definable (result); 16726 /* Always make artificials weak. */ 16727 if (DECL_ARTIFICIAL (result) && flag_weak) 16728 comdat_linkage (result); 16729 /* For WIN32 we also want to put explicit instantiations in 16730 linkonce sections. */ 16731 else if (TREE_PUBLIC (result)) 16732 maybe_make_one_only (result); 16733 } 16734 16735 /* If EXTERN_P, then this function will not be emitted -- unless 16736 followed by an explicit instantiation, at which point its linkage 16737 will be adjusted. If !EXTERN_P, then this function will be 16738 emitted here. In neither circumstance do we want 16739 import_export_decl to adjust the linkage. */ 16740 DECL_INTERFACE_KNOWN (result) = 1; 16741 } 16742 16743 /* Subroutine of more_specialized_fn: check whether TARGS is missing any 16744 important template arguments. If any are missing, we check whether 16745 they're important by using error_mark_node for substituting into any 16746 args that were used for partial ordering (the ones between ARGS and END) 16747 and seeing if it bubbles up. */ 16748 16749 static bool 16750 check_undeduced_parms (tree targs, tree args, tree end) 16751 { 16752 bool found = false; 16753 int i; 16754 for (i = TREE_VEC_LENGTH (targs) - 1; i >= 0; --i) 16755 if (TREE_VEC_ELT (targs, i) == NULL_TREE) 16756 { 16757 found = true; 16758 TREE_VEC_ELT (targs, i) = error_mark_node; 16759 } 16760 if (found) 16761 { 16762 tree substed = tsubst_arg_types (args, targs, end, tf_none, NULL_TREE); 16763 if (substed == error_mark_node) 16764 return true; 16765 } 16766 return false; 16767 } 16768 16769 /* Given two function templates PAT1 and PAT2, return: 16770 16771 1 if PAT1 is more specialized than PAT2 as described in [temp.func.order]. 16772 -1 if PAT2 is more specialized than PAT1. 16773 0 if neither is more specialized. 16774 16775 LEN indicates the number of parameters we should consider 16776 (defaulted parameters should not be considered). 16777 16778 The 1998 std underspecified function template partial ordering, and 16779 DR214 addresses the issue. We take pairs of arguments, one from 16780 each of the templates, and deduce them against each other. One of 16781 the templates will be more specialized if all the *other* 16782 template's arguments deduce against its arguments and at least one 16783 of its arguments *does* *not* deduce against the other template's 16784 corresponding argument. Deduction is done as for class templates. 16785 The arguments used in deduction have reference and top level cv 16786 qualifiers removed. Iff both arguments were originally reference 16787 types *and* deduction succeeds in both directions, the template 16788 with the more cv-qualified argument wins for that pairing (if 16789 neither is more cv-qualified, they both are equal). Unlike regular 16790 deduction, after all the arguments have been deduced in this way, 16791 we do *not* verify the deduced template argument values can be 16792 substituted into non-deduced contexts. 16793 16794 The logic can be a bit confusing here, because we look at deduce1 and 16795 targs1 to see if pat2 is at least as specialized, and vice versa; if we 16796 can find template arguments for pat1 to make arg1 look like arg2, that 16797 means that arg2 is at least as specialized as arg1. */ 16798 16799 int 16800 more_specialized_fn (tree pat1, tree pat2, int len) 16801 { 16802 tree decl1 = DECL_TEMPLATE_RESULT (pat1); 16803 tree decl2 = DECL_TEMPLATE_RESULT (pat2); 16804 tree targs1 = make_tree_vec (DECL_NTPARMS (pat1)); 16805 tree targs2 = make_tree_vec (DECL_NTPARMS (pat2)); 16806 tree tparms1 = DECL_INNERMOST_TEMPLATE_PARMS (pat1); 16807 tree tparms2 = DECL_INNERMOST_TEMPLATE_PARMS (pat2); 16808 tree args1 = TYPE_ARG_TYPES (TREE_TYPE (decl1)); 16809 tree args2 = TYPE_ARG_TYPES (TREE_TYPE (decl2)); 16810 tree origs1, origs2; 16811 bool lose1 = false; 16812 bool lose2 = false; 16813 16814 /* Remove the this parameter from non-static member functions. If 16815 one is a non-static member function and the other is not a static 16816 member function, remove the first parameter from that function 16817 also. This situation occurs for operator functions where we 16818 locate both a member function (with this pointer) and non-member 16819 operator (with explicit first operand). */ 16820 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl1)) 16821 { 16822 len--; /* LEN is the number of significant arguments for DECL1 */ 16823 args1 = TREE_CHAIN (args1); 16824 if (!DECL_STATIC_FUNCTION_P (decl2)) 16825 args2 = TREE_CHAIN (args2); 16826 } 16827 else if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl2)) 16828 { 16829 args2 = TREE_CHAIN (args2); 16830 if (!DECL_STATIC_FUNCTION_P (decl1)) 16831 { 16832 len--; 16833 args1 = TREE_CHAIN (args1); 16834 } 16835 } 16836 16837 /* If only one is a conversion operator, they are unordered. */ 16838 if (DECL_CONV_FN_P (decl1) != DECL_CONV_FN_P (decl2)) 16839 return 0; 16840 16841 /* Consider the return type for a conversion function */ 16842 if (DECL_CONV_FN_P (decl1)) 16843 { 16844 args1 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl1)), args1); 16845 args2 = tree_cons (NULL_TREE, TREE_TYPE (TREE_TYPE (decl2)), args2); 16846 len++; 16847 } 16848 16849 processing_template_decl++; 16850 16851 origs1 = args1; 16852 origs2 = args2; 16853 16854 while (len-- 16855 /* Stop when an ellipsis is seen. */ 16856 && args1 != NULL_TREE && args2 != NULL_TREE) 16857 { 16858 tree arg1 = TREE_VALUE (args1); 16859 tree arg2 = TREE_VALUE (args2); 16860 int deduce1, deduce2; 16861 int quals1 = -1; 16862 int quals2 = -1; 16863 16864 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION 16865 && TREE_CODE (arg2) == TYPE_PACK_EXPANSION) 16866 { 16867 /* When both arguments are pack expansions, we need only 16868 unify the patterns themselves. */ 16869 arg1 = PACK_EXPANSION_PATTERN (arg1); 16870 arg2 = PACK_EXPANSION_PATTERN (arg2); 16871 16872 /* This is the last comparison we need to do. */ 16873 len = 0; 16874 } 16875 16876 if (TREE_CODE (arg1) == REFERENCE_TYPE) 16877 { 16878 arg1 = TREE_TYPE (arg1); 16879 quals1 = cp_type_quals (arg1); 16880 } 16881 16882 if (TREE_CODE (arg2) == REFERENCE_TYPE) 16883 { 16884 arg2 = TREE_TYPE (arg2); 16885 quals2 = cp_type_quals (arg2); 16886 } 16887 16888 if ((quals1 < 0) != (quals2 < 0)) 16889 { 16890 /* Only of the args is a reference, see if we should apply 16891 array/function pointer decay to it. This is not part of 16892 DR214, but is, IMHO, consistent with the deduction rules 16893 for the function call itself, and with our earlier 16894 implementation of the underspecified partial ordering 16895 rules. (nathan). */ 16896 if (quals1 >= 0) 16897 { 16898 switch (TREE_CODE (arg1)) 16899 { 16900 case ARRAY_TYPE: 16901 arg1 = TREE_TYPE (arg1); 16902 /* FALLTHROUGH. */ 16903 case FUNCTION_TYPE: 16904 arg1 = build_pointer_type (arg1); 16905 break; 16906 16907 default: 16908 break; 16909 } 16910 } 16911 else 16912 { 16913 switch (TREE_CODE (arg2)) 16914 { 16915 case ARRAY_TYPE: 16916 arg2 = TREE_TYPE (arg2); 16917 /* FALLTHROUGH. */ 16918 case FUNCTION_TYPE: 16919 arg2 = build_pointer_type (arg2); 16920 break; 16921 16922 default: 16923 break; 16924 } 16925 } 16926 } 16927 16928 arg1 = TYPE_MAIN_VARIANT (arg1); 16929 arg2 = TYPE_MAIN_VARIANT (arg2); 16930 16931 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION) 16932 { 16933 int i, len2 = list_length (args2); 16934 tree parmvec = make_tree_vec (1); 16935 tree argvec = make_tree_vec (len2); 16936 tree ta = args2; 16937 16938 /* Setup the parameter vector, which contains only ARG1. */ 16939 TREE_VEC_ELT (parmvec, 0) = arg1; 16940 16941 /* Setup the argument vector, which contains the remaining 16942 arguments. */ 16943 for (i = 0; i < len2; i++, ta = TREE_CHAIN (ta)) 16944 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta); 16945 16946 deduce1 = (unify_pack_expansion (tparms1, targs1, parmvec, 16947 argvec, DEDUCE_EXACT, 16948 /*subr=*/true, /*explain_p=*/false) 16949 == 0); 16950 16951 /* We cannot deduce in the other direction, because ARG1 is 16952 a pack expansion but ARG2 is not. */ 16953 deduce2 = 0; 16954 } 16955 else if (TREE_CODE (arg2) == TYPE_PACK_EXPANSION) 16956 { 16957 int i, len1 = list_length (args1); 16958 tree parmvec = make_tree_vec (1); 16959 tree argvec = make_tree_vec (len1); 16960 tree ta = args1; 16961 16962 /* Setup the parameter vector, which contains only ARG1. */ 16963 TREE_VEC_ELT (parmvec, 0) = arg2; 16964 16965 /* Setup the argument vector, which contains the remaining 16966 arguments. */ 16967 for (i = 0; i < len1; i++, ta = TREE_CHAIN (ta)) 16968 TREE_VEC_ELT (argvec, i) = TREE_VALUE (ta); 16969 16970 deduce2 = (unify_pack_expansion (tparms2, targs2, parmvec, 16971 argvec, DEDUCE_EXACT, 16972 /*subr=*/true, /*explain_p=*/false) 16973 == 0); 16974 16975 /* We cannot deduce in the other direction, because ARG2 is 16976 a pack expansion but ARG1 is not.*/ 16977 deduce1 = 0; 16978 } 16979 16980 else 16981 { 16982 /* The normal case, where neither argument is a pack 16983 expansion. */ 16984 deduce1 = (unify (tparms1, targs1, arg1, arg2, 16985 UNIFY_ALLOW_NONE, /*explain_p=*/false) 16986 == 0); 16987 deduce2 = (unify (tparms2, targs2, arg2, arg1, 16988 UNIFY_ALLOW_NONE, /*explain_p=*/false) 16989 == 0); 16990 } 16991 16992 /* If we couldn't deduce arguments for tparms1 to make arg1 match 16993 arg2, then arg2 is not as specialized as arg1. */ 16994 if (!deduce1) 16995 lose2 = true; 16996 if (!deduce2) 16997 lose1 = true; 16998 16999 /* "If, for a given type, deduction succeeds in both directions 17000 (i.e., the types are identical after the transformations above) 17001 and if the type from the argument template is more cv-qualified 17002 than the type from the parameter template (as described above) 17003 that type is considered to be more specialized than the other. If 17004 neither type is more cv-qualified than the other then neither type 17005 is more specialized than the other." */ 17006 17007 if (deduce1 && deduce2 17008 && quals1 != quals2 && quals1 >= 0 && quals2 >= 0) 17009 { 17010 if ((quals1 & quals2) == quals2) 17011 lose2 = true; 17012 if ((quals1 & quals2) == quals1) 17013 lose1 = true; 17014 } 17015 17016 if (lose1 && lose2) 17017 /* We've failed to deduce something in either direction. 17018 These must be unordered. */ 17019 break; 17020 17021 if (TREE_CODE (arg1) == TYPE_PACK_EXPANSION 17022 || TREE_CODE (arg2) == TYPE_PACK_EXPANSION) 17023 /* We have already processed all of the arguments in our 17024 handing of the pack expansion type. */ 17025 len = 0; 17026 17027 args1 = TREE_CHAIN (args1); 17028 args2 = TREE_CHAIN (args2); 17029 } 17030 17031 /* "In most cases, all template parameters must have values in order for 17032 deduction to succeed, but for partial ordering purposes a template 17033 parameter may remain without a value provided it is not used in the 17034 types being used for partial ordering." 17035 17036 Thus, if we are missing any of the targs1 we need to substitute into 17037 origs1, then pat2 is not as specialized as pat1. This can happen when 17038 there is a nondeduced context. */ 17039 if (!lose2 && check_undeduced_parms (targs1, origs1, args1)) 17040 lose2 = true; 17041 if (!lose1 && check_undeduced_parms (targs2, origs2, args2)) 17042 lose1 = true; 17043 17044 processing_template_decl--; 17045 17046 /* All things being equal, if the next argument is a pack expansion 17047 for one function but not for the other, prefer the 17048 non-variadic function. FIXME this is bogus; see c++/41958. */ 17049 if (lose1 == lose2 17050 && args1 && TREE_VALUE (args1) 17051 && args2 && TREE_VALUE (args2)) 17052 { 17053 lose1 = TREE_CODE (TREE_VALUE (args1)) == TYPE_PACK_EXPANSION; 17054 lose2 = TREE_CODE (TREE_VALUE (args2)) == TYPE_PACK_EXPANSION; 17055 } 17056 17057 if (lose1 == lose2) 17058 return 0; 17059 else if (!lose1) 17060 return 1; 17061 else 17062 return -1; 17063 } 17064 17065 /* Determine which of two partial specializations is more specialized. 17066 17067 PAT1 is a TREE_LIST whose TREE_TYPE is the _TYPE node corresponding 17068 to the first partial specialization. The TREE_VALUE is the 17069 innermost set of template parameters for the partial 17070 specialization. PAT2 is similar, but for the second template. 17071 17072 Return 1 if the first partial specialization is more specialized; 17073 -1 if the second is more specialized; 0 if neither is more 17074 specialized. 17075 17076 See [temp.class.order] for information about determining which of 17077 two templates is more specialized. */ 17078 17079 static int 17080 more_specialized_class (tree pat1, tree pat2) 17081 { 17082 tree targs; 17083 tree tmpl1, tmpl2; 17084 int winner = 0; 17085 bool any_deductions = false; 17086 17087 tmpl1 = TREE_TYPE (pat1); 17088 tmpl2 = TREE_TYPE (pat2); 17089 17090 /* Just like what happens for functions, if we are ordering between 17091 different class template specializations, we may encounter dependent 17092 types in the arguments, and we need our dependency check functions 17093 to behave correctly. */ 17094 ++processing_template_decl; 17095 targs = get_class_bindings (TREE_VALUE (pat1), 17096 CLASSTYPE_TI_ARGS (tmpl1), 17097 CLASSTYPE_TI_ARGS (tmpl2)); 17098 if (targs) 17099 { 17100 --winner; 17101 any_deductions = true; 17102 } 17103 17104 targs = get_class_bindings (TREE_VALUE (pat2), 17105 CLASSTYPE_TI_ARGS (tmpl2), 17106 CLASSTYPE_TI_ARGS (tmpl1)); 17107 if (targs) 17108 { 17109 ++winner; 17110 any_deductions = true; 17111 } 17112 --processing_template_decl; 17113 17114 /* In the case of a tie where at least one of the class templates 17115 has a parameter pack at the end, the template with the most 17116 non-packed parameters wins. */ 17117 if (winner == 0 17118 && any_deductions 17119 && (template_args_variadic_p (TREE_PURPOSE (pat1)) 17120 || template_args_variadic_p (TREE_PURPOSE (pat2)))) 17121 { 17122 tree args1 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat1)); 17123 tree args2 = INNERMOST_TEMPLATE_ARGS (TREE_PURPOSE (pat2)); 17124 int len1 = TREE_VEC_LENGTH (args1); 17125 int len2 = TREE_VEC_LENGTH (args2); 17126 17127 /* We don't count the pack expansion at the end. */ 17128 if (template_args_variadic_p (TREE_PURPOSE (pat1))) 17129 --len1; 17130 if (template_args_variadic_p (TREE_PURPOSE (pat2))) 17131 --len2; 17132 17133 if (len1 > len2) 17134 return 1; 17135 else if (len1 < len2) 17136 return -1; 17137 } 17138 17139 return winner; 17140 } 17141 17142 /* Return the template arguments that will produce the function signature 17143 DECL from the function template FN, with the explicit template 17144 arguments EXPLICIT_ARGS. If CHECK_RETTYPE is true, the return type must 17145 also match. Return NULL_TREE if no satisfactory arguments could be 17146 found. */ 17147 17148 static tree 17149 get_bindings (tree fn, tree decl, tree explicit_args, bool check_rettype) 17150 { 17151 int ntparms = DECL_NTPARMS (fn); 17152 tree targs = make_tree_vec (ntparms); 17153 tree decl_type; 17154 tree decl_arg_types; 17155 tree *args; 17156 unsigned int nargs, ix; 17157 tree arg; 17158 17159 /* Substitute the explicit template arguments into the type of DECL. 17160 The call to fn_type_unification will handle substitution into the 17161 FN. */ 17162 decl_type = TREE_TYPE (decl); 17163 if (explicit_args && uses_template_parms (decl_type)) 17164 { 17165 tree tmpl; 17166 tree converted_args; 17167 17168 if (DECL_TEMPLATE_INFO (decl)) 17169 tmpl = DECL_TI_TEMPLATE (decl); 17170 else 17171 /* We can get here for some invalid specializations. */ 17172 return NULL_TREE; 17173 17174 converted_args 17175 = coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl), 17176 explicit_args, NULL_TREE, 17177 tf_none, 17178 /*require_all_args=*/false, 17179 /*use_default_args=*/false); 17180 if (converted_args == error_mark_node) 17181 return NULL_TREE; 17182 17183 decl_type = tsubst (decl_type, converted_args, tf_none, NULL_TREE); 17184 if (decl_type == error_mark_node) 17185 return NULL_TREE; 17186 } 17187 17188 /* Never do unification on the 'this' parameter. */ 17189 decl_arg_types = skip_artificial_parms_for (decl, 17190 TYPE_ARG_TYPES (decl_type)); 17191 17192 nargs = list_length (decl_arg_types); 17193 args = XALLOCAVEC (tree, nargs); 17194 for (arg = decl_arg_types, ix = 0; 17195 arg != NULL_TREE && arg != void_list_node; 17196 arg = TREE_CHAIN (arg), ++ix) 17197 args[ix] = TREE_VALUE (arg); 17198 17199 if (fn_type_unification (fn, explicit_args, targs, 17200 args, ix, 17201 (check_rettype || DECL_CONV_FN_P (fn) 17202 ? TREE_TYPE (decl_type) : NULL_TREE), 17203 DEDUCE_EXACT, LOOKUP_NORMAL, /*explain_p=*/false)) 17204 return NULL_TREE; 17205 17206 return targs; 17207 } 17208 17209 /* Return the innermost template arguments that, when applied to a 17210 template specialization whose innermost template parameters are 17211 TPARMS, and whose specialization arguments are SPEC_ARGS, yield the 17212 ARGS. 17213 17214 For example, suppose we have: 17215 17216 template <class T, class U> struct S {}; 17217 template <class T> struct S<T*, int> {}; 17218 17219 Then, suppose we want to get `S<double*, int>'. The TPARMS will be 17220 {T}, the SPEC_ARGS will be {T*, int} and the ARGS will be {double*, 17221 int}. The resulting vector will be {double}, indicating that `T' 17222 is bound to `double'. */ 17223 17224 static tree 17225 get_class_bindings (tree tparms, tree spec_args, tree args) 17226 { 17227 int i, ntparms = TREE_VEC_LENGTH (tparms); 17228 tree deduced_args; 17229 tree innermost_deduced_args; 17230 17231 innermost_deduced_args = make_tree_vec (ntparms); 17232 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args)) 17233 { 17234 deduced_args = copy_node (args); 17235 SET_TMPL_ARGS_LEVEL (deduced_args, 17236 TMPL_ARGS_DEPTH (deduced_args), 17237 innermost_deduced_args); 17238 } 17239 else 17240 deduced_args = innermost_deduced_args; 17241 17242 if (unify (tparms, deduced_args, 17243 INNERMOST_TEMPLATE_ARGS (spec_args), 17244 INNERMOST_TEMPLATE_ARGS (args), 17245 UNIFY_ALLOW_NONE, /*explain_p=*/false)) 17246 return NULL_TREE; 17247 17248 for (i = 0; i < ntparms; ++i) 17249 if (! TREE_VEC_ELT (innermost_deduced_args, i)) 17250 return NULL_TREE; 17251 17252 /* Verify that nondeduced template arguments agree with the type 17253 obtained from argument deduction. 17254 17255 For example: 17256 17257 struct A { typedef int X; }; 17258 template <class T, class U> struct C {}; 17259 template <class T> struct C<T, typename T::X> {}; 17260 17261 Then with the instantiation `C<A, int>', we can deduce that 17262 `T' is `A' but unify () does not check whether `typename T::X' 17263 is `int'. */ 17264 spec_args = tsubst (spec_args, deduced_args, tf_none, NULL_TREE); 17265 if (spec_args == error_mark_node 17266 /* We only need to check the innermost arguments; the other 17267 arguments will always agree. */ 17268 || !comp_template_args (INNERMOST_TEMPLATE_ARGS (spec_args), 17269 INNERMOST_TEMPLATE_ARGS (args))) 17270 return NULL_TREE; 17271 17272 /* Now that we have bindings for all of the template arguments, 17273 ensure that the arguments deduced for the template template 17274 parameters have compatible template parameter lists. See the use 17275 of template_template_parm_bindings_ok_p in fn_type_unification 17276 for more information. */ 17277 if (!template_template_parm_bindings_ok_p (tparms, deduced_args)) 17278 return NULL_TREE; 17279 17280 return deduced_args; 17281 } 17282 17283 /* TEMPLATES is a TREE_LIST. Each TREE_VALUE is a TEMPLATE_DECL. 17284 Return the TREE_LIST node with the most specialized template, if 17285 any. If there is no most specialized template, the error_mark_node 17286 is returned. 17287 17288 Note that this function does not look at, or modify, the 17289 TREE_PURPOSE or TREE_TYPE of any of the nodes. Since the node 17290 returned is one of the elements of INSTANTIATIONS, callers may 17291 store information in the TREE_PURPOSE or TREE_TYPE of the nodes, 17292 and retrieve it from the value returned. */ 17293 17294 tree 17295 most_specialized_instantiation (tree templates) 17296 { 17297 tree fn, champ; 17298 17299 ++processing_template_decl; 17300 17301 champ = templates; 17302 for (fn = TREE_CHAIN (templates); fn; fn = TREE_CHAIN (fn)) 17303 { 17304 int fate = 0; 17305 17306 if (get_bindings (TREE_VALUE (champ), 17307 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)), 17308 NULL_TREE, /*check_ret=*/true)) 17309 fate--; 17310 17311 if (get_bindings (TREE_VALUE (fn), 17312 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)), 17313 NULL_TREE, /*check_ret=*/true)) 17314 fate++; 17315 17316 if (fate == -1) 17317 champ = fn; 17318 else if (!fate) 17319 { 17320 /* Equally specialized, move to next function. If there 17321 is no next function, nothing's most specialized. */ 17322 fn = TREE_CHAIN (fn); 17323 champ = fn; 17324 if (!fn) 17325 break; 17326 } 17327 } 17328 17329 if (champ) 17330 /* Now verify that champ is better than everything earlier in the 17331 instantiation list. */ 17332 for (fn = templates; fn != champ; fn = TREE_CHAIN (fn)) 17333 if (get_bindings (TREE_VALUE (champ), 17334 DECL_TEMPLATE_RESULT (TREE_VALUE (fn)), 17335 NULL_TREE, /*check_ret=*/true) 17336 || !get_bindings (TREE_VALUE (fn), 17337 DECL_TEMPLATE_RESULT (TREE_VALUE (champ)), 17338 NULL_TREE, /*check_ret=*/true)) 17339 { 17340 champ = NULL_TREE; 17341 break; 17342 } 17343 17344 processing_template_decl--; 17345 17346 if (!champ) 17347 return error_mark_node; 17348 17349 return champ; 17350 } 17351 17352 /* If DECL is a specialization of some template, return the most 17353 general such template. Otherwise, returns NULL_TREE. 17354 17355 For example, given: 17356 17357 template <class T> struct S { template <class U> void f(U); }; 17358 17359 if TMPL is `template <class U> void S<int>::f(U)' this will return 17360 the full template. This function will not trace past partial 17361 specializations, however. For example, given in addition: 17362 17363 template <class T> struct S<T*> { template <class U> void f(U); }; 17364 17365 if TMPL is `template <class U> void S<int*>::f(U)' this will return 17366 `template <class T> template <class U> S<T*>::f(U)'. */ 17367 17368 tree 17369 most_general_template (tree decl) 17370 { 17371 /* If DECL is a FUNCTION_DECL, find the TEMPLATE_DECL of which it is 17372 an immediate specialization. */ 17373 if (TREE_CODE (decl) == FUNCTION_DECL) 17374 { 17375 if (DECL_TEMPLATE_INFO (decl)) { 17376 decl = DECL_TI_TEMPLATE (decl); 17377 17378 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE for a 17379 template friend. */ 17380 if (TREE_CODE (decl) != TEMPLATE_DECL) 17381 return NULL_TREE; 17382 } else 17383 return NULL_TREE; 17384 } 17385 17386 /* Look for more and more general templates. */ 17387 while (DECL_TEMPLATE_INFO (decl)) 17388 { 17389 /* The DECL_TI_TEMPLATE can be an IDENTIFIER_NODE in some cases. 17390 (See cp-tree.h for details.) */ 17391 if (TREE_CODE (DECL_TI_TEMPLATE (decl)) != TEMPLATE_DECL) 17392 break; 17393 17394 if (CLASS_TYPE_P (TREE_TYPE (decl)) 17395 && CLASSTYPE_TEMPLATE_SPECIALIZATION (TREE_TYPE (decl))) 17396 break; 17397 17398 /* Stop if we run into an explicitly specialized class template. */ 17399 if (!DECL_NAMESPACE_SCOPE_P (decl) 17400 && DECL_CONTEXT (decl) 17401 && CLASSTYPE_TEMPLATE_SPECIALIZATION (DECL_CONTEXT (decl))) 17402 break; 17403 17404 decl = DECL_TI_TEMPLATE (decl); 17405 } 17406 17407 return decl; 17408 } 17409 17410 /* Return the most specialized of the class template partial 17411 specializations of TMPL which can produce TYPE, a specialization of 17412 TMPL. The value returned is actually a TREE_LIST; the TREE_TYPE is 17413 a _TYPE node corresponding to the partial specialization, while the 17414 TREE_PURPOSE is the set of template arguments that must be 17415 substituted into the TREE_TYPE in order to generate TYPE. 17416 17417 If the choice of partial specialization is ambiguous, a diagnostic 17418 is issued, and the error_mark_node is returned. If there are no 17419 partial specializations of TMPL matching TYPE, then NULL_TREE is 17420 returned. */ 17421 17422 static tree 17423 most_specialized_class (tree type, tree tmpl, tsubst_flags_t complain) 17424 { 17425 tree list = NULL_TREE; 17426 tree t; 17427 tree champ; 17428 int fate; 17429 bool ambiguous_p; 17430 tree args; 17431 tree outer_args = NULL_TREE; 17432 17433 tmpl = most_general_template (tmpl); 17434 args = CLASSTYPE_TI_ARGS (type); 17435 17436 /* For determining which partial specialization to use, only the 17437 innermost args are interesting. */ 17438 if (TMPL_ARGS_HAVE_MULTIPLE_LEVELS (args)) 17439 { 17440 outer_args = strip_innermost_template_args (args, 1); 17441 args = INNERMOST_TEMPLATE_ARGS (args); 17442 } 17443 17444 for (t = DECL_TEMPLATE_SPECIALIZATIONS (tmpl); t; t = TREE_CHAIN (t)) 17445 { 17446 tree partial_spec_args; 17447 tree spec_args; 17448 tree parms = TREE_VALUE (t); 17449 17450 partial_spec_args = CLASSTYPE_TI_ARGS (TREE_TYPE (t)); 17451 17452 ++processing_template_decl; 17453 17454 if (outer_args) 17455 { 17456 int i; 17457 17458 /* Discard the outer levels of args, and then substitute in the 17459 template args from the enclosing class. */ 17460 partial_spec_args = INNERMOST_TEMPLATE_ARGS (partial_spec_args); 17461 partial_spec_args = tsubst_template_args 17462 (partial_spec_args, outer_args, tf_none, NULL_TREE); 17463 17464 /* PARMS already refers to just the innermost parms, but the 17465 template parms in partial_spec_args had their levels lowered 17466 by tsubst, so we need to do the same for the parm list. We 17467 can't just tsubst the TREE_VEC itself, as tsubst wants to 17468 treat a TREE_VEC as an argument vector. */ 17469 parms = copy_node (parms); 17470 for (i = TREE_VEC_LENGTH (parms) - 1; i >= 0; --i) 17471 TREE_VEC_ELT (parms, i) = 17472 tsubst (TREE_VEC_ELT (parms, i), outer_args, tf_none, NULL_TREE); 17473 17474 } 17475 17476 partial_spec_args = 17477 coerce_template_parms (DECL_INNERMOST_TEMPLATE_PARMS (tmpl), 17478 add_to_template_args (outer_args, 17479 partial_spec_args), 17480 tmpl, tf_none, 17481 /*require_all_args=*/true, 17482 /*use_default_args=*/true); 17483 17484 --processing_template_decl; 17485 17486 if (partial_spec_args == error_mark_node) 17487 return error_mark_node; 17488 17489 spec_args = get_class_bindings (parms, 17490 partial_spec_args, 17491 args); 17492 if (spec_args) 17493 { 17494 if (outer_args) 17495 spec_args = add_to_template_args (outer_args, spec_args); 17496 list = tree_cons (spec_args, TREE_VALUE (t), list); 17497 TREE_TYPE (list) = TREE_TYPE (t); 17498 } 17499 } 17500 17501 if (! list) 17502 return NULL_TREE; 17503 17504 ambiguous_p = false; 17505 t = list; 17506 champ = t; 17507 t = TREE_CHAIN (t); 17508 for (; t; t = TREE_CHAIN (t)) 17509 { 17510 fate = more_specialized_class (champ, t); 17511 if (fate == 1) 17512 ; 17513 else 17514 { 17515 if (fate == 0) 17516 { 17517 t = TREE_CHAIN (t); 17518 if (! t) 17519 { 17520 ambiguous_p = true; 17521 break; 17522 } 17523 } 17524 champ = t; 17525 } 17526 } 17527 17528 if (!ambiguous_p) 17529 for (t = list; t && t != champ; t = TREE_CHAIN (t)) 17530 { 17531 fate = more_specialized_class (champ, t); 17532 if (fate != 1) 17533 { 17534 ambiguous_p = true; 17535 break; 17536 } 17537 } 17538 17539 if (ambiguous_p) 17540 { 17541 const char *str; 17542 char *spaces = NULL; 17543 if (!(complain & tf_error)) 17544 return error_mark_node; 17545 error ("ambiguous class template instantiation for %q#T", type); 17546 str = ngettext ("candidate is:", "candidates are:", list_length (list)); 17547 for (t = list; t; t = TREE_CHAIN (t)) 17548 { 17549 error ("%s %+#T", spaces ? spaces : str, TREE_TYPE (t)); 17550 spaces = spaces ? spaces : get_spaces (str); 17551 } 17552 free (spaces); 17553 return error_mark_node; 17554 } 17555 17556 return champ; 17557 } 17558 17559 /* Explicitly instantiate DECL. */ 17560 17561 void 17562 do_decl_instantiation (tree decl, tree storage) 17563 { 17564 tree result = NULL_TREE; 17565 int extern_p = 0; 17566 17567 if (!decl || decl == error_mark_node) 17568 /* An error occurred, for which grokdeclarator has already issued 17569 an appropriate message. */ 17570 return; 17571 else if (! DECL_LANG_SPECIFIC (decl)) 17572 { 17573 error ("explicit instantiation of non-template %q#D", decl); 17574 return; 17575 } 17576 else if (TREE_CODE (decl) == VAR_DECL) 17577 { 17578 /* There is an asymmetry here in the way VAR_DECLs and 17579 FUNCTION_DECLs are handled by grokdeclarator. In the case of 17580 the latter, the DECL we get back will be marked as a 17581 template instantiation, and the appropriate 17582 DECL_TEMPLATE_INFO will be set up. This does not happen for 17583 VAR_DECLs so we do the lookup here. Probably, grokdeclarator 17584 should handle VAR_DECLs as it currently handles 17585 FUNCTION_DECLs. */ 17586 if (!DECL_CLASS_SCOPE_P (decl)) 17587 { 17588 error ("%qD is not a static data member of a class template", decl); 17589 return; 17590 } 17591 result = lookup_field (DECL_CONTEXT (decl), DECL_NAME (decl), 0, false); 17592 if (!result || TREE_CODE (result) != VAR_DECL) 17593 { 17594 error ("no matching template for %qD found", decl); 17595 return; 17596 } 17597 if (!same_type_p (TREE_TYPE (result), TREE_TYPE (decl))) 17598 { 17599 error ("type %qT for explicit instantiation %qD does not match " 17600 "declared type %qT", TREE_TYPE (result), decl, 17601 TREE_TYPE (decl)); 17602 return; 17603 } 17604 } 17605 else if (TREE_CODE (decl) != FUNCTION_DECL) 17606 { 17607 error ("explicit instantiation of %q#D", decl); 17608 return; 17609 } 17610 else 17611 result = decl; 17612 17613 /* Check for various error cases. Note that if the explicit 17614 instantiation is valid the RESULT will currently be marked as an 17615 *implicit* instantiation; DECL_EXPLICIT_INSTANTIATION is not set 17616 until we get here. */ 17617 17618 if (DECL_TEMPLATE_SPECIALIZATION (result)) 17619 { 17620 /* DR 259 [temp.spec]. 17621 17622 Both an explicit instantiation and a declaration of an explicit 17623 specialization shall not appear in a program unless the explicit 17624 instantiation follows a declaration of the explicit specialization. 17625 17626 For a given set of template parameters, if an explicit 17627 instantiation of a template appears after a declaration of an 17628 explicit specialization for that template, the explicit 17629 instantiation has no effect. */ 17630 return; 17631 } 17632 else if (DECL_EXPLICIT_INSTANTIATION (result)) 17633 { 17634 /* [temp.spec] 17635 17636 No program shall explicitly instantiate any template more 17637 than once. 17638 17639 We check DECL_NOT_REALLY_EXTERN so as not to complain when 17640 the first instantiation was `extern' and the second is not, 17641 and EXTERN_P for the opposite case. */ 17642 if (DECL_NOT_REALLY_EXTERN (result) && !extern_p) 17643 permerror (input_location, "duplicate explicit instantiation of %q#D", result); 17644 /* If an "extern" explicit instantiation follows an ordinary 17645 explicit instantiation, the template is instantiated. */ 17646 if (extern_p) 17647 return; 17648 } 17649 else if (!DECL_IMPLICIT_INSTANTIATION (result)) 17650 { 17651 error ("no matching template for %qD found", result); 17652 return; 17653 } 17654 else if (!DECL_TEMPLATE_INFO (result)) 17655 { 17656 permerror (input_location, "explicit instantiation of non-template %q#D", result); 17657 return; 17658 } 17659 17660 if (storage == NULL_TREE) 17661 ; 17662 else if (storage == ridpointers[(int) RID_EXTERN]) 17663 { 17664 if (!in_system_header && (cxx_dialect == cxx98)) 17665 pedwarn (input_location, OPT_pedantic, 17666 "ISO C++ 1998 forbids the use of %<extern%> on explicit " 17667 "instantiations"); 17668 extern_p = 1; 17669 } 17670 else 17671 error ("storage class %qD applied to template instantiation", storage); 17672 17673 check_explicit_instantiation_namespace (result); 17674 mark_decl_instantiated (result, extern_p); 17675 if (! extern_p) 17676 instantiate_decl (result, /*defer_ok=*/1, 17677 /*expl_inst_class_mem_p=*/false); 17678 } 17679 17680 static void 17681 mark_class_instantiated (tree t, int extern_p) 17682 { 17683 SET_CLASSTYPE_EXPLICIT_INSTANTIATION (t); 17684 SET_CLASSTYPE_INTERFACE_KNOWN (t); 17685 CLASSTYPE_INTERFACE_ONLY (t) = extern_p; 17686 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (t)) = extern_p; 17687 if (! extern_p) 17688 { 17689 CLASSTYPE_DEBUG_REQUESTED (t) = 1; 17690 rest_of_type_compilation (t, 1); 17691 } 17692 } 17693 17694 /* Called from do_type_instantiation through binding_table_foreach to 17695 do recursive instantiation for the type bound in ENTRY. */ 17696 static void 17697 bt_instantiate_type_proc (binding_entry entry, void *data) 17698 { 17699 tree storage = *(tree *) data; 17700 17701 if (MAYBE_CLASS_TYPE_P (entry->type) 17702 && !uses_template_parms (CLASSTYPE_TI_ARGS (entry->type))) 17703 do_type_instantiation (TYPE_MAIN_DECL (entry->type), storage, 0); 17704 } 17705 17706 /* Called from do_type_instantiation to instantiate a member 17707 (a member function or a static member variable) of an 17708 explicitly instantiated class template. */ 17709 static void 17710 instantiate_class_member (tree decl, int extern_p) 17711 { 17712 mark_decl_instantiated (decl, extern_p); 17713 if (! extern_p) 17714 instantiate_decl (decl, /*defer_ok=*/1, 17715 /*expl_inst_class_mem_p=*/true); 17716 } 17717 17718 /* Perform an explicit instantiation of template class T. STORAGE, if 17719 non-null, is the RID for extern, inline or static. COMPLAIN is 17720 nonzero if this is called from the parser, zero if called recursively, 17721 since the standard is unclear (as detailed below). */ 17722 17723 void 17724 do_type_instantiation (tree t, tree storage, tsubst_flags_t complain) 17725 { 17726 int extern_p = 0; 17727 int nomem_p = 0; 17728 int static_p = 0; 17729 int previous_instantiation_extern_p = 0; 17730 17731 if (TREE_CODE (t) == TYPE_DECL) 17732 t = TREE_TYPE (t); 17733 17734 if (! CLASS_TYPE_P (t) || ! CLASSTYPE_TEMPLATE_INFO (t)) 17735 { 17736 tree tmpl = 17737 (TYPE_TEMPLATE_INFO (t)) ? TYPE_TI_TEMPLATE (t) : NULL; 17738 if (tmpl) 17739 error ("explicit instantiation of non-class template %qD", tmpl); 17740 else 17741 error ("explicit instantiation of non-template type %qT", t); 17742 return; 17743 } 17744 17745 complete_type (t); 17746 17747 if (!COMPLETE_TYPE_P (t)) 17748 { 17749 if (complain & tf_error) 17750 error ("explicit instantiation of %q#T before definition of template", 17751 t); 17752 return; 17753 } 17754 17755 if (storage != NULL_TREE) 17756 { 17757 if (!in_system_header) 17758 { 17759 if (storage == ridpointers[(int) RID_EXTERN]) 17760 { 17761 if (cxx_dialect == cxx98) 17762 pedwarn (input_location, OPT_pedantic, 17763 "ISO C++ 1998 forbids the use of %<extern%> on " 17764 "explicit instantiations"); 17765 } 17766 else 17767 pedwarn (input_location, OPT_pedantic, 17768 "ISO C++ forbids the use of %qE" 17769 " on explicit instantiations", storage); 17770 } 17771 17772 if (storage == ridpointers[(int) RID_INLINE]) 17773 nomem_p = 1; 17774 else if (storage == ridpointers[(int) RID_EXTERN]) 17775 extern_p = 1; 17776 else if (storage == ridpointers[(int) RID_STATIC]) 17777 static_p = 1; 17778 else 17779 { 17780 error ("storage class %qD applied to template instantiation", 17781 storage); 17782 extern_p = 0; 17783 } 17784 } 17785 17786 if (CLASSTYPE_TEMPLATE_SPECIALIZATION (t)) 17787 { 17788 /* DR 259 [temp.spec]. 17789 17790 Both an explicit instantiation and a declaration of an explicit 17791 specialization shall not appear in a program unless the explicit 17792 instantiation follows a declaration of the explicit specialization. 17793 17794 For a given set of template parameters, if an explicit 17795 instantiation of a template appears after a declaration of an 17796 explicit specialization for that template, the explicit 17797 instantiation has no effect. */ 17798 return; 17799 } 17800 else if (CLASSTYPE_EXPLICIT_INSTANTIATION (t)) 17801 { 17802 /* [temp.spec] 17803 17804 No program shall explicitly instantiate any template more 17805 than once. 17806 17807 If PREVIOUS_INSTANTIATION_EXTERN_P, then the first explicit 17808 instantiation was `extern'. If EXTERN_P then the second is. 17809 These cases are OK. */ 17810 previous_instantiation_extern_p = CLASSTYPE_INTERFACE_ONLY (t); 17811 17812 if (!previous_instantiation_extern_p && !extern_p 17813 && (complain & tf_error)) 17814 permerror (input_location, "duplicate explicit instantiation of %q#T", t); 17815 17816 /* If we've already instantiated the template, just return now. */ 17817 if (!CLASSTYPE_INTERFACE_ONLY (t)) 17818 return; 17819 } 17820 17821 check_explicit_instantiation_namespace (TYPE_NAME (t)); 17822 mark_class_instantiated (t, extern_p); 17823 17824 if (nomem_p) 17825 return; 17826 17827 { 17828 tree tmp; 17829 17830 /* In contrast to implicit instantiation, where only the 17831 declarations, and not the definitions, of members are 17832 instantiated, we have here: 17833 17834 [temp.explicit] 17835 17836 The explicit instantiation of a class template specialization 17837 implies the instantiation of all of its members not 17838 previously explicitly specialized in the translation unit 17839 containing the explicit instantiation. 17840 17841 Of course, we can't instantiate member template classes, since 17842 we don't have any arguments for them. Note that the standard 17843 is unclear on whether the instantiation of the members are 17844 *explicit* instantiations or not. However, the most natural 17845 interpretation is that it should be an explicit instantiation. */ 17846 17847 if (! static_p) 17848 for (tmp = TYPE_METHODS (t); tmp; tmp = DECL_CHAIN (tmp)) 17849 if (TREE_CODE (tmp) == FUNCTION_DECL 17850 && DECL_TEMPLATE_INSTANTIATION (tmp)) 17851 instantiate_class_member (tmp, extern_p); 17852 17853 for (tmp = TYPE_FIELDS (t); tmp; tmp = DECL_CHAIN (tmp)) 17854 if (TREE_CODE (tmp) == VAR_DECL && DECL_TEMPLATE_INSTANTIATION (tmp)) 17855 instantiate_class_member (tmp, extern_p); 17856 17857 if (CLASSTYPE_NESTED_UTDS (t)) 17858 binding_table_foreach (CLASSTYPE_NESTED_UTDS (t), 17859 bt_instantiate_type_proc, &storage); 17860 } 17861 } 17862 17863 /* Given a function DECL, which is a specialization of TMPL, modify 17864 DECL to be a re-instantiation of TMPL with the same template 17865 arguments. TMPL should be the template into which tsubst'ing 17866 should occur for DECL, not the most general template. 17867 17868 One reason for doing this is a scenario like this: 17869 17870 template <class T> 17871 void f(const T&, int i); 17872 17873 void g() { f(3, 7); } 17874 17875 template <class T> 17876 void f(const T& t, const int i) { } 17877 17878 Note that when the template is first instantiated, with 17879 instantiate_template, the resulting DECL will have no name for the 17880 first parameter, and the wrong type for the second. So, when we go 17881 to instantiate the DECL, we regenerate it. */ 17882 17883 static void 17884 regenerate_decl_from_template (tree decl, tree tmpl) 17885 { 17886 /* The arguments used to instantiate DECL, from the most general 17887 template. */ 17888 tree args; 17889 tree code_pattern; 17890 17891 args = DECL_TI_ARGS (decl); 17892 code_pattern = DECL_TEMPLATE_RESULT (tmpl); 17893 17894 /* Make sure that we can see identifiers, and compute access 17895 correctly. */ 17896 push_access_scope (decl); 17897 17898 if (TREE_CODE (decl) == FUNCTION_DECL) 17899 { 17900 tree decl_parm; 17901 tree pattern_parm; 17902 tree specs; 17903 int args_depth; 17904 int parms_depth; 17905 17906 args_depth = TMPL_ARGS_DEPTH (args); 17907 parms_depth = TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (tmpl)); 17908 if (args_depth > parms_depth) 17909 args = get_innermost_template_args (args, parms_depth); 17910 17911 specs = tsubst_exception_specification (TREE_TYPE (code_pattern), 17912 args, tf_error, NULL_TREE, 17913 /*defer_ok*/false); 17914 if (specs && specs != error_mark_node) 17915 TREE_TYPE (decl) = build_exception_variant (TREE_TYPE (decl), 17916 specs); 17917 17918 /* Merge parameter declarations. */ 17919 decl_parm = skip_artificial_parms_for (decl, 17920 DECL_ARGUMENTS (decl)); 17921 pattern_parm 17922 = skip_artificial_parms_for (code_pattern, 17923 DECL_ARGUMENTS (code_pattern)); 17924 while (decl_parm && !FUNCTION_PARAMETER_PACK_P (pattern_parm)) 17925 { 17926 tree parm_type; 17927 tree attributes; 17928 17929 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm)) 17930 DECL_NAME (decl_parm) = DECL_NAME (pattern_parm); 17931 parm_type = tsubst (TREE_TYPE (pattern_parm), args, tf_error, 17932 NULL_TREE); 17933 parm_type = type_decays_to (parm_type); 17934 if (!same_type_p (TREE_TYPE (decl_parm), parm_type)) 17935 TREE_TYPE (decl_parm) = parm_type; 17936 attributes = DECL_ATTRIBUTES (pattern_parm); 17937 if (DECL_ATTRIBUTES (decl_parm) != attributes) 17938 { 17939 DECL_ATTRIBUTES (decl_parm) = attributes; 17940 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0); 17941 } 17942 decl_parm = DECL_CHAIN (decl_parm); 17943 pattern_parm = DECL_CHAIN (pattern_parm); 17944 } 17945 /* Merge any parameters that match with the function parameter 17946 pack. */ 17947 if (pattern_parm && FUNCTION_PARAMETER_PACK_P (pattern_parm)) 17948 { 17949 int i, len; 17950 tree expanded_types; 17951 /* Expand the TYPE_PACK_EXPANSION that provides the types for 17952 the parameters in this function parameter pack. */ 17953 expanded_types = tsubst_pack_expansion (TREE_TYPE (pattern_parm), 17954 args, tf_error, NULL_TREE); 17955 len = TREE_VEC_LENGTH (expanded_types); 17956 for (i = 0; i < len; i++) 17957 { 17958 tree parm_type; 17959 tree attributes; 17960 17961 if (DECL_NAME (decl_parm) != DECL_NAME (pattern_parm)) 17962 /* Rename the parameter to include the index. */ 17963 DECL_NAME (decl_parm) = 17964 make_ith_pack_parameter_name (DECL_NAME (pattern_parm), i); 17965 parm_type = TREE_VEC_ELT (expanded_types, i); 17966 parm_type = type_decays_to (parm_type); 17967 if (!same_type_p (TREE_TYPE (decl_parm), parm_type)) 17968 TREE_TYPE (decl_parm) = parm_type; 17969 attributes = DECL_ATTRIBUTES (pattern_parm); 17970 if (DECL_ATTRIBUTES (decl_parm) != attributes) 17971 { 17972 DECL_ATTRIBUTES (decl_parm) = attributes; 17973 cplus_decl_attributes (&decl_parm, attributes, /*flags=*/0); 17974 } 17975 decl_parm = DECL_CHAIN (decl_parm); 17976 } 17977 } 17978 /* Merge additional specifiers from the CODE_PATTERN. */ 17979 if (DECL_DECLARED_INLINE_P (code_pattern) 17980 && !DECL_DECLARED_INLINE_P (decl)) 17981 DECL_DECLARED_INLINE_P (decl) = 1; 17982 } 17983 else if (TREE_CODE (decl) == VAR_DECL) 17984 { 17985 DECL_INITIAL (decl) = 17986 tsubst_expr (DECL_INITIAL (code_pattern), args, 17987 tf_error, DECL_TI_TEMPLATE (decl), 17988 /*integral_constant_expression_p=*/false); 17989 if (VAR_HAD_UNKNOWN_BOUND (decl)) 17990 TREE_TYPE (decl) = tsubst (TREE_TYPE (code_pattern), args, 17991 tf_error, DECL_TI_TEMPLATE (decl)); 17992 } 17993 else 17994 gcc_unreachable (); 17995 17996 pop_access_scope (decl); 17997 } 17998 17999 /* Return the TEMPLATE_DECL into which DECL_TI_ARGS(DECL) should be 18000 substituted to get DECL. */ 18001 18002 tree 18003 template_for_substitution (tree decl) 18004 { 18005 tree tmpl = DECL_TI_TEMPLATE (decl); 18006 18007 /* Set TMPL to the template whose DECL_TEMPLATE_RESULT is the pattern 18008 for the instantiation. This is not always the most general 18009 template. Consider, for example: 18010 18011 template <class T> 18012 struct S { template <class U> void f(); 18013 template <> void f<int>(); }; 18014 18015 and an instantiation of S<double>::f<int>. We want TD to be the 18016 specialization S<T>::f<int>, not the more general S<T>::f<U>. */ 18017 while (/* An instantiation cannot have a definition, so we need a 18018 more general template. */ 18019 DECL_TEMPLATE_INSTANTIATION (tmpl) 18020 /* We must also deal with friend templates. Given: 18021 18022 template <class T> struct S { 18023 template <class U> friend void f() {}; 18024 }; 18025 18026 S<int>::f<U> say, is not an instantiation of S<T>::f<U>, 18027 so far as the language is concerned, but that's still 18028 where we get the pattern for the instantiation from. On 18029 other hand, if the definition comes outside the class, say: 18030 18031 template <class T> struct S { 18032 template <class U> friend void f(); 18033 }; 18034 template <class U> friend void f() {} 18035 18036 we don't need to look any further. That's what the check for 18037 DECL_INITIAL is for. */ 18038 || (TREE_CODE (decl) == FUNCTION_DECL 18039 && DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (tmpl) 18040 && !DECL_INITIAL (DECL_TEMPLATE_RESULT (tmpl)))) 18041 { 18042 /* The present template, TD, should not be a definition. If it 18043 were a definition, we should be using it! Note that we 18044 cannot restructure the loop to just keep going until we find 18045 a template with a definition, since that might go too far if 18046 a specialization was declared, but not defined. */ 18047 gcc_assert (TREE_CODE (decl) != VAR_DECL 18048 || DECL_IN_AGGR_P (DECL_TEMPLATE_RESULT (tmpl))); 18049 18050 /* Fetch the more general template. */ 18051 tmpl = DECL_TI_TEMPLATE (tmpl); 18052 } 18053 18054 return tmpl; 18055 } 18056 18057 /* Returns true if we need to instantiate this template instance even if we 18058 know we aren't going to emit it.. */ 18059 18060 bool 18061 always_instantiate_p (tree decl) 18062 { 18063 /* We always instantiate inline functions so that we can inline them. An 18064 explicit instantiation declaration prohibits implicit instantiation of 18065 non-inline functions. With high levels of optimization, we would 18066 normally inline non-inline functions -- but we're not allowed to do 18067 that for "extern template" functions. Therefore, we check 18068 DECL_DECLARED_INLINE_P, rather than possibly_inlined_p. */ 18069 return ((TREE_CODE (decl) == FUNCTION_DECL 18070 && DECL_DECLARED_INLINE_P (decl)) 18071 /* And we need to instantiate static data members so that 18072 their initializers are available in integral constant 18073 expressions. */ 18074 || (TREE_CODE (decl) == VAR_DECL 18075 && decl_maybe_constant_var_p (decl))); 18076 } 18077 18078 /* If FN has a noexcept-specifier that hasn't been instantiated yet, 18079 instantiate it now, modifying TREE_TYPE (fn). */ 18080 18081 void 18082 maybe_instantiate_noexcept (tree fn) 18083 { 18084 tree fntype, spec, noex, clone; 18085 18086 if (DECL_CLONED_FUNCTION_P (fn)) 18087 fn = DECL_CLONED_FUNCTION (fn); 18088 fntype = TREE_TYPE (fn); 18089 spec = TYPE_RAISES_EXCEPTIONS (fntype); 18090 18091 if (!DEFERRED_NOEXCEPT_SPEC_P (spec)) 18092 return; 18093 18094 noex = TREE_PURPOSE (spec); 18095 18096 if (TREE_CODE (noex) == DEFERRED_NOEXCEPT) 18097 { 18098 if (push_tinst_level (fn)) 18099 { 18100 push_access_scope (fn); 18101 push_deferring_access_checks (dk_no_deferred); 18102 input_location = DECL_SOURCE_LOCATION (fn); 18103 noex = tsubst_copy_and_build (DEFERRED_NOEXCEPT_PATTERN (noex), 18104 DEFERRED_NOEXCEPT_ARGS (noex), 18105 tf_warning_or_error, fn, 18106 /*function_p=*/false, 18107 /*integral_constant_expression_p=*/true); 18108 pop_deferring_access_checks (); 18109 pop_access_scope (fn); 18110 pop_tinst_level (); 18111 spec = build_noexcept_spec (noex, tf_warning_or_error); 18112 if (spec == error_mark_node) 18113 spec = noexcept_false_spec; 18114 } 18115 else 18116 spec = noexcept_false_spec; 18117 } 18118 else 18119 { 18120 /* This is an implicitly declared function, so NOEX is a list of 18121 other functions to evaluate and merge. */ 18122 tree elt; 18123 spec = noexcept_true_spec; 18124 for (elt = noex; elt; elt = OVL_NEXT (elt)) 18125 { 18126 tree fn = OVL_CURRENT (elt); 18127 tree subspec; 18128 maybe_instantiate_noexcept (fn); 18129 subspec = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn)); 18130 spec = merge_exception_specifiers (spec, subspec, NULL_TREE); 18131 } 18132 } 18133 18134 TREE_TYPE (fn) = build_exception_variant (fntype, spec); 18135 18136 FOR_EACH_CLONE (clone, fn) 18137 { 18138 if (TREE_TYPE (clone) == fntype) 18139 TREE_TYPE (clone) = TREE_TYPE (fn); 18140 else 18141 TREE_TYPE (clone) = build_exception_variant (TREE_TYPE (clone), spec); 18142 } 18143 } 18144 18145 /* Produce the definition of D, a _DECL generated from a template. If 18146 DEFER_OK is nonzero, then we don't have to actually do the 18147 instantiation now; we just have to do it sometime. Normally it is 18148 an error if this is an explicit instantiation but D is undefined. 18149 EXPL_INST_CLASS_MEM_P is true iff D is a member of an 18150 explicitly instantiated class template. */ 18151 18152 tree 18153 instantiate_decl (tree d, int defer_ok, 18154 bool expl_inst_class_mem_p) 18155 { 18156 tree tmpl = DECL_TI_TEMPLATE (d); 18157 tree gen_args; 18158 tree args; 18159 tree td; 18160 tree code_pattern; 18161 tree spec; 18162 tree gen_tmpl; 18163 bool pattern_defined; 18164 location_t saved_loc = input_location; 18165 bool external_p; 18166 tree fn_context; 18167 bool nested; 18168 18169 /* This function should only be used to instantiate templates for 18170 functions and static member variables. */ 18171 gcc_assert (TREE_CODE (d) == FUNCTION_DECL 18172 || TREE_CODE (d) == VAR_DECL); 18173 18174 /* Variables are never deferred; if instantiation is required, they 18175 are instantiated right away. That allows for better code in the 18176 case that an expression refers to the value of the variable -- 18177 if the variable has a constant value the referring expression can 18178 take advantage of that fact. */ 18179 if (TREE_CODE (d) == VAR_DECL 18180 || DECL_DECLARED_CONSTEXPR_P (d)) 18181 defer_ok = 0; 18182 18183 /* Don't instantiate cloned functions. Instead, instantiate the 18184 functions they cloned. */ 18185 if (TREE_CODE (d) == FUNCTION_DECL && DECL_CLONED_FUNCTION_P (d)) 18186 d = DECL_CLONED_FUNCTION (d); 18187 18188 if (DECL_TEMPLATE_INSTANTIATED (d) 18189 || (TREE_CODE (d) == FUNCTION_DECL 18190 && DECL_DEFAULTED_FN (d) && DECL_INITIAL (d)) 18191 || DECL_TEMPLATE_SPECIALIZATION (d)) 18192 /* D has already been instantiated or explicitly specialized, so 18193 there's nothing for us to do here. 18194 18195 It might seem reasonable to check whether or not D is an explicit 18196 instantiation, and, if so, stop here. But when an explicit 18197 instantiation is deferred until the end of the compilation, 18198 DECL_EXPLICIT_INSTANTIATION is set, even though we still need to do 18199 the instantiation. */ 18200 return d; 18201 18202 /* Check to see whether we know that this template will be 18203 instantiated in some other file, as with "extern template" 18204 extension. */ 18205 external_p = (DECL_INTERFACE_KNOWN (d) && DECL_REALLY_EXTERN (d)); 18206 18207 /* In general, we do not instantiate such templates. */ 18208 if (external_p && !always_instantiate_p (d)) 18209 return d; 18210 18211 gen_tmpl = most_general_template (tmpl); 18212 gen_args = DECL_TI_ARGS (d); 18213 18214 if (tmpl != gen_tmpl) 18215 /* We should already have the extra args. */ 18216 gcc_assert (TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (gen_tmpl)) 18217 == TMPL_ARGS_DEPTH (gen_args)); 18218 /* And what's in the hash table should match D. */ 18219 gcc_assert ((spec = retrieve_specialization (gen_tmpl, gen_args, 0)) == d 18220 || spec == NULL_TREE); 18221 18222 /* This needs to happen before any tsubsting. */ 18223 if (! push_tinst_level (d)) 18224 return d; 18225 18226 timevar_push (TV_TEMPLATE_INST); 18227 18228 /* Set TD to the template whose DECL_TEMPLATE_RESULT is the pattern 18229 for the instantiation. */ 18230 td = template_for_substitution (d); 18231 code_pattern = DECL_TEMPLATE_RESULT (td); 18232 18233 /* We should never be trying to instantiate a member of a class 18234 template or partial specialization. */ 18235 gcc_assert (d != code_pattern); 18236 18237 if ((DECL_NAMESPACE_SCOPE_P (d) && !DECL_INITIALIZED_IN_CLASS_P (d)) 18238 || DECL_TEMPLATE_SPECIALIZATION (td)) 18239 /* In the case of a friend template whose definition is provided 18240 outside the class, we may have too many arguments. Drop the 18241 ones we don't need. The same is true for specializations. */ 18242 args = get_innermost_template_args 18243 (gen_args, TMPL_PARMS_DEPTH (DECL_TEMPLATE_PARMS (td))); 18244 else 18245 args = gen_args; 18246 18247 if (TREE_CODE (d) == FUNCTION_DECL) 18248 pattern_defined = (DECL_SAVED_TREE (code_pattern) != NULL_TREE 18249 || DECL_DEFAULTED_OUTSIDE_CLASS_P (code_pattern)); 18250 else 18251 pattern_defined = ! DECL_IN_AGGR_P (code_pattern); 18252 18253 /* We may be in the middle of deferred access check. Disable it now. */ 18254 push_deferring_access_checks (dk_no_deferred); 18255 18256 /* Unless an explicit instantiation directive has already determined 18257 the linkage of D, remember that a definition is available for 18258 this entity. */ 18259 if (pattern_defined 18260 && !DECL_INTERFACE_KNOWN (d) 18261 && !DECL_NOT_REALLY_EXTERN (d)) 18262 mark_definable (d); 18263 18264 DECL_SOURCE_LOCATION (td) = DECL_SOURCE_LOCATION (code_pattern); 18265 DECL_SOURCE_LOCATION (d) = DECL_SOURCE_LOCATION (code_pattern); 18266 input_location = DECL_SOURCE_LOCATION (d); 18267 18268 /* If D is a member of an explicitly instantiated class template, 18269 and no definition is available, treat it like an implicit 18270 instantiation. */ 18271 if (!pattern_defined && expl_inst_class_mem_p 18272 && DECL_EXPLICIT_INSTANTIATION (d)) 18273 { 18274 /* Leave linkage flags alone on instantiations with anonymous 18275 visibility. */ 18276 if (TREE_PUBLIC (d)) 18277 { 18278 DECL_NOT_REALLY_EXTERN (d) = 0; 18279 DECL_INTERFACE_KNOWN (d) = 0; 18280 } 18281 SET_DECL_IMPLICIT_INSTANTIATION (d); 18282 } 18283 18284 if (TREE_CODE (d) == FUNCTION_DECL) 18285 maybe_instantiate_noexcept (d); 18286 18287 /* Recheck the substitutions to obtain any warning messages 18288 about ignoring cv qualifiers. Don't do this for artificial decls, 18289 as it breaks the context-sensitive substitution for lambda op(). */ 18290 if (!defer_ok && !DECL_ARTIFICIAL (d)) 18291 { 18292 tree gen = DECL_TEMPLATE_RESULT (gen_tmpl); 18293 tree type = TREE_TYPE (gen); 18294 18295 /* Make sure that we can see identifiers, and compute access 18296 correctly. D is already the target FUNCTION_DECL with the 18297 right context. */ 18298 push_access_scope (d); 18299 18300 if (TREE_CODE (gen) == FUNCTION_DECL) 18301 { 18302 tsubst (DECL_ARGUMENTS (gen), gen_args, tf_warning_or_error, d); 18303 tsubst_exception_specification (type, gen_args, tf_warning_or_error, 18304 d, /*defer_ok*/true); 18305 /* Don't simply tsubst the function type, as that will give 18306 duplicate warnings about poor parameter qualifications. 18307 The function arguments are the same as the decl_arguments 18308 without the top level cv qualifiers. */ 18309 type = TREE_TYPE (type); 18310 } 18311 tsubst (type, gen_args, tf_warning_or_error, d); 18312 18313 pop_access_scope (d); 18314 } 18315 18316 /* Defer all other templates, unless we have been explicitly 18317 forbidden from doing so. */ 18318 if (/* If there is no definition, we cannot instantiate the 18319 template. */ 18320 ! pattern_defined 18321 /* If it's OK to postpone instantiation, do so. */ 18322 || defer_ok 18323 /* If this is a static data member that will be defined 18324 elsewhere, we don't want to instantiate the entire data 18325 member, but we do want to instantiate the initializer so that 18326 we can substitute that elsewhere. */ 18327 || (external_p && TREE_CODE (d) == VAR_DECL)) 18328 { 18329 /* The definition of the static data member is now required so 18330 we must substitute the initializer. */ 18331 if (TREE_CODE (d) == VAR_DECL 18332 && !DECL_INITIAL (d) 18333 && DECL_INITIAL (code_pattern)) 18334 { 18335 tree ns; 18336 tree init; 18337 bool const_init = false; 18338 18339 ns = decl_namespace_context (d); 18340 push_nested_namespace (ns); 18341 push_nested_class (DECL_CONTEXT (d)); 18342 init = tsubst_expr (DECL_INITIAL (code_pattern), 18343 args, 18344 tf_warning_or_error, NULL_TREE, 18345 /*integral_constant_expression_p=*/false); 18346 /* Make sure the initializer is still constant, in case of 18347 circular dependency (template/instantiate6.C). */ 18348 const_init 18349 = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern); 18350 cp_finish_decl (d, init, /*init_const_expr_p=*/const_init, 18351 /*asmspec_tree=*/NULL_TREE, 18352 LOOKUP_ONLYCONVERTING); 18353 pop_nested_class (); 18354 pop_nested_namespace (ns); 18355 } 18356 18357 /* We restore the source position here because it's used by 18358 add_pending_template. */ 18359 input_location = saved_loc; 18360 18361 if (at_eof && !pattern_defined 18362 && DECL_EXPLICIT_INSTANTIATION (d) 18363 && DECL_NOT_REALLY_EXTERN (d)) 18364 /* [temp.explicit] 18365 18366 The definition of a non-exported function template, a 18367 non-exported member function template, or a non-exported 18368 member function or static data member of a class template 18369 shall be present in every translation unit in which it is 18370 explicitly instantiated. */ 18371 permerror (input_location, "explicit instantiation of %qD " 18372 "but no definition available", d); 18373 18374 /* If we're in unevaluated context, we just wanted to get the 18375 constant value; this isn't an odr use, so don't queue 18376 a full instantiation. */ 18377 if (cp_unevaluated_operand != 0) 18378 goto out; 18379 /* ??? Historically, we have instantiated inline functions, even 18380 when marked as "extern template". */ 18381 if (!(external_p && TREE_CODE (d) == VAR_DECL)) 18382 add_pending_template (d); 18383 goto out; 18384 } 18385 /* Tell the repository that D is available in this translation unit 18386 -- and see if it is supposed to be instantiated here. */ 18387 if (TREE_PUBLIC (d) && !DECL_REALLY_EXTERN (d) && !repo_emit_p (d)) 18388 { 18389 /* In a PCH file, despite the fact that the repository hasn't 18390 requested instantiation in the PCH it is still possible that 18391 an instantiation will be required in a file that includes the 18392 PCH. */ 18393 if (pch_file) 18394 add_pending_template (d); 18395 /* Instantiate inline functions so that the inliner can do its 18396 job, even though we'll not be emitting a copy of this 18397 function. */ 18398 if (!(TREE_CODE (d) == FUNCTION_DECL && possibly_inlined_p (d))) 18399 goto out; 18400 } 18401 18402 fn_context = decl_function_context (d); 18403 nested = (current_function_decl != NULL_TREE); 18404 if (!fn_context) 18405 push_to_top_level (); 18406 else if (nested) 18407 push_function_context (); 18408 18409 /* Mark D as instantiated so that recursive calls to 18410 instantiate_decl do not try to instantiate it again. */ 18411 DECL_TEMPLATE_INSTANTIATED (d) = 1; 18412 18413 /* Regenerate the declaration in case the template has been modified 18414 by a subsequent redeclaration. */ 18415 regenerate_decl_from_template (d, td); 18416 18417 /* We already set the file and line above. Reset them now in case 18418 they changed as a result of calling regenerate_decl_from_template. */ 18419 input_location = DECL_SOURCE_LOCATION (d); 18420 18421 if (TREE_CODE (d) == VAR_DECL) 18422 { 18423 tree init; 18424 bool const_init = false; 18425 18426 /* Clear out DECL_RTL; whatever was there before may not be right 18427 since we've reset the type of the declaration. */ 18428 SET_DECL_RTL (d, NULL); 18429 DECL_IN_AGGR_P (d) = 0; 18430 18431 /* The initializer is placed in DECL_INITIAL by 18432 regenerate_decl_from_template so we don't need to 18433 push/pop_access_scope again here. Pull it out so that 18434 cp_finish_decl can process it. */ 18435 init = DECL_INITIAL (d); 18436 DECL_INITIAL (d) = NULL_TREE; 18437 DECL_INITIALIZED_P (d) = 0; 18438 18439 /* Clear DECL_EXTERNAL so that cp_finish_decl will process the 18440 initializer. That function will defer actual emission until 18441 we have a chance to determine linkage. */ 18442 DECL_EXTERNAL (d) = 0; 18443 18444 /* Enter the scope of D so that access-checking works correctly. */ 18445 push_nested_class (DECL_CONTEXT (d)); 18446 const_init = DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (code_pattern); 18447 cp_finish_decl (d, init, const_init, NULL_TREE, 0); 18448 pop_nested_class (); 18449 } 18450 else if (TREE_CODE (d) == FUNCTION_DECL && DECL_DEFAULTED_FN (code_pattern)) 18451 synthesize_method (d); 18452 else if (TREE_CODE (d) == FUNCTION_DECL) 18453 { 18454 htab_t saved_local_specializations; 18455 tree subst_decl; 18456 tree tmpl_parm; 18457 tree spec_parm; 18458 18459 /* Save away the current list, in case we are instantiating one 18460 template from within the body of another. */ 18461 saved_local_specializations = local_specializations; 18462 18463 /* Set up the list of local specializations. */ 18464 local_specializations = htab_create (37, 18465 hash_local_specialization, 18466 eq_local_specializations, 18467 NULL); 18468 18469 /* Set up context. */ 18470 start_preparsed_function (d, NULL_TREE, SF_PRE_PARSED); 18471 18472 /* Create substitution entries for the parameters. */ 18473 subst_decl = DECL_TEMPLATE_RESULT (template_for_substitution (d)); 18474 tmpl_parm = DECL_ARGUMENTS (subst_decl); 18475 spec_parm = DECL_ARGUMENTS (d); 18476 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (d)) 18477 { 18478 register_local_specialization (spec_parm, tmpl_parm); 18479 spec_parm = skip_artificial_parms_for (d, spec_parm); 18480 tmpl_parm = skip_artificial_parms_for (subst_decl, tmpl_parm); 18481 } 18482 for (; tmpl_parm; tmpl_parm = DECL_CHAIN (tmpl_parm)) 18483 { 18484 if (!FUNCTION_PARAMETER_PACK_P (tmpl_parm)) 18485 { 18486 register_local_specialization (spec_parm, tmpl_parm); 18487 spec_parm = DECL_CHAIN (spec_parm); 18488 } 18489 else 18490 { 18491 /* Register the (value) argument pack as a specialization of 18492 TMPL_PARM, then move on. */ 18493 tree argpack = extract_fnparm_pack (tmpl_parm, &spec_parm); 18494 register_local_specialization (argpack, tmpl_parm); 18495 } 18496 } 18497 gcc_assert (!spec_parm); 18498 18499 /* Substitute into the body of the function. */ 18500 tsubst_expr (DECL_SAVED_TREE (code_pattern), args, 18501 tf_warning_or_error, tmpl, 18502 /*integral_constant_expression_p=*/false); 18503 18504 /* Set the current input_location to the end of the function 18505 so that finish_function knows where we are. */ 18506 input_location = DECL_STRUCT_FUNCTION (code_pattern)->function_end_locus; 18507 18508 /* We don't need the local specializations any more. */ 18509 htab_delete (local_specializations); 18510 local_specializations = saved_local_specializations; 18511 18512 /* Finish the function. */ 18513 d = finish_function (0); 18514 expand_or_defer_fn (d); 18515 } 18516 18517 /* We're not deferring instantiation any more. */ 18518 TI_PENDING_TEMPLATE_FLAG (DECL_TEMPLATE_INFO (d)) = 0; 18519 18520 if (!fn_context) 18521 pop_from_top_level (); 18522 else if (nested) 18523 pop_function_context (); 18524 18525 out: 18526 input_location = saved_loc; 18527 pop_deferring_access_checks (); 18528 pop_tinst_level (); 18529 18530 timevar_pop (TV_TEMPLATE_INST); 18531 18532 return d; 18533 } 18534 18535 /* Run through the list of templates that we wish we could 18536 instantiate, and instantiate any we can. RETRIES is the 18537 number of times we retry pending template instantiation. */ 18538 18539 void 18540 instantiate_pending_templates (int retries) 18541 { 18542 int reconsider; 18543 location_t saved_loc = input_location; 18544 18545 /* Instantiating templates may trigger vtable generation. This in turn 18546 may require further template instantiations. We place a limit here 18547 to avoid infinite loop. */ 18548 if (pending_templates && retries >= max_tinst_depth) 18549 { 18550 tree decl = pending_templates->tinst->decl; 18551 18552 error ("template instantiation depth exceeds maximum of %d" 18553 " instantiating %q+D, possibly from virtual table generation" 18554 " (use -ftemplate-depth= to increase the maximum)", 18555 max_tinst_depth, decl); 18556 if (TREE_CODE (decl) == FUNCTION_DECL) 18557 /* Pretend that we defined it. */ 18558 DECL_INITIAL (decl) = error_mark_node; 18559 return; 18560 } 18561 18562 do 18563 { 18564 struct pending_template **t = &pending_templates; 18565 struct pending_template *last = NULL; 18566 reconsider = 0; 18567 while (*t) 18568 { 18569 tree instantiation = reopen_tinst_level ((*t)->tinst); 18570 bool complete = false; 18571 18572 if (TYPE_P (instantiation)) 18573 { 18574 tree fn; 18575 18576 if (!COMPLETE_TYPE_P (instantiation)) 18577 { 18578 instantiate_class_template (instantiation); 18579 if (CLASSTYPE_TEMPLATE_INSTANTIATION (instantiation)) 18580 for (fn = TYPE_METHODS (instantiation); 18581 fn; 18582 fn = TREE_CHAIN (fn)) 18583 if (! DECL_ARTIFICIAL (fn)) 18584 instantiate_decl (fn, 18585 /*defer_ok=*/0, 18586 /*expl_inst_class_mem_p=*/false); 18587 if (COMPLETE_TYPE_P (instantiation)) 18588 reconsider = 1; 18589 } 18590 18591 complete = COMPLETE_TYPE_P (instantiation); 18592 } 18593 else 18594 { 18595 if (!DECL_TEMPLATE_SPECIALIZATION (instantiation) 18596 && !DECL_TEMPLATE_INSTANTIATED (instantiation)) 18597 { 18598 instantiation 18599 = instantiate_decl (instantiation, 18600 /*defer_ok=*/0, 18601 /*expl_inst_class_mem_p=*/false); 18602 if (DECL_TEMPLATE_INSTANTIATED (instantiation)) 18603 reconsider = 1; 18604 } 18605 18606 complete = (DECL_TEMPLATE_SPECIALIZATION (instantiation) 18607 || DECL_TEMPLATE_INSTANTIATED (instantiation)); 18608 } 18609 18610 if (complete) 18611 /* If INSTANTIATION has been instantiated, then we don't 18612 need to consider it again in the future. */ 18613 *t = (*t)->next; 18614 else 18615 { 18616 last = *t; 18617 t = &(*t)->next; 18618 } 18619 tinst_depth = 0; 18620 current_tinst_level = NULL; 18621 } 18622 last_pending_template = last; 18623 } 18624 while (reconsider); 18625 18626 input_location = saved_loc; 18627 } 18628 18629 /* Substitute ARGVEC into T, which is a list of initializers for 18630 either base class or a non-static data member. The TREE_PURPOSEs 18631 are DECLs, and the TREE_VALUEs are the initializer values. Used by 18632 instantiate_decl. */ 18633 18634 static tree 18635 tsubst_initializer_list (tree t, tree argvec) 18636 { 18637 tree inits = NULL_TREE; 18638 18639 for (; t; t = TREE_CHAIN (t)) 18640 { 18641 tree decl; 18642 tree init; 18643 tree expanded_bases = NULL_TREE; 18644 tree expanded_arguments = NULL_TREE; 18645 int i, len = 1; 18646 18647 if (TREE_CODE (TREE_PURPOSE (t)) == TYPE_PACK_EXPANSION) 18648 { 18649 tree expr; 18650 tree arg; 18651 18652 /* Expand the base class expansion type into separate base 18653 classes. */ 18654 expanded_bases = tsubst_pack_expansion (TREE_PURPOSE (t), argvec, 18655 tf_warning_or_error, 18656 NULL_TREE); 18657 if (expanded_bases == error_mark_node) 18658 continue; 18659 18660 /* We'll be building separate TREE_LISTs of arguments for 18661 each base. */ 18662 len = TREE_VEC_LENGTH (expanded_bases); 18663 expanded_arguments = make_tree_vec (len); 18664 for (i = 0; i < len; i++) 18665 TREE_VEC_ELT (expanded_arguments, i) = NULL_TREE; 18666 18667 /* Build a dummy EXPR_PACK_EXPANSION that will be used to 18668 expand each argument in the TREE_VALUE of t. */ 18669 expr = make_node (EXPR_PACK_EXPANSION); 18670 PACK_EXPANSION_LOCAL_P (expr) = true; 18671 PACK_EXPANSION_PARAMETER_PACKS (expr) = 18672 PACK_EXPANSION_PARAMETER_PACKS (TREE_PURPOSE (t)); 18673 18674 if (TREE_VALUE (t) == void_type_node) 18675 /* VOID_TYPE_NODE is used to indicate 18676 value-initialization. */ 18677 { 18678 for (i = 0; i < len; i++) 18679 TREE_VEC_ELT (expanded_arguments, i) = void_type_node; 18680 } 18681 else 18682 { 18683 /* Substitute parameter packs into each argument in the 18684 TREE_LIST. */ 18685 in_base_initializer = 1; 18686 for (arg = TREE_VALUE (t); arg; arg = TREE_CHAIN (arg)) 18687 { 18688 tree expanded_exprs; 18689 18690 /* Expand the argument. */ 18691 SET_PACK_EXPANSION_PATTERN (expr, TREE_VALUE (arg)); 18692 expanded_exprs 18693 = tsubst_pack_expansion (expr, argvec, 18694 tf_warning_or_error, 18695 NULL_TREE); 18696 if (expanded_exprs == error_mark_node) 18697 continue; 18698 18699 /* Prepend each of the expanded expressions to the 18700 corresponding TREE_LIST in EXPANDED_ARGUMENTS. */ 18701 for (i = 0; i < len; i++) 18702 { 18703 TREE_VEC_ELT (expanded_arguments, i) = 18704 tree_cons (NULL_TREE, 18705 TREE_VEC_ELT (expanded_exprs, i), 18706 TREE_VEC_ELT (expanded_arguments, i)); 18707 } 18708 } 18709 in_base_initializer = 0; 18710 18711 /* Reverse all of the TREE_LISTs in EXPANDED_ARGUMENTS, 18712 since we built them backwards. */ 18713 for (i = 0; i < len; i++) 18714 { 18715 TREE_VEC_ELT (expanded_arguments, i) = 18716 nreverse (TREE_VEC_ELT (expanded_arguments, i)); 18717 } 18718 } 18719 } 18720 18721 for (i = 0; i < len; ++i) 18722 { 18723 if (expanded_bases) 18724 { 18725 decl = TREE_VEC_ELT (expanded_bases, i); 18726 decl = expand_member_init (decl); 18727 init = TREE_VEC_ELT (expanded_arguments, i); 18728 } 18729 else 18730 { 18731 tree tmp; 18732 decl = tsubst_copy (TREE_PURPOSE (t), argvec, 18733 tf_warning_or_error, NULL_TREE); 18734 18735 decl = expand_member_init (decl); 18736 if (decl && !DECL_P (decl)) 18737 in_base_initializer = 1; 18738 18739 init = TREE_VALUE (t); 18740 tmp = init; 18741 if (init != void_type_node) 18742 init = tsubst_expr (init, argvec, 18743 tf_warning_or_error, NULL_TREE, 18744 /*integral_constant_expression_p=*/false); 18745 if (init == NULL_TREE && tmp != NULL_TREE) 18746 /* If we had an initializer but it instantiated to nothing, 18747 value-initialize the object. This will only occur when 18748 the initializer was a pack expansion where the parameter 18749 packs used in that expansion were of length zero. */ 18750 init = void_type_node; 18751 in_base_initializer = 0; 18752 } 18753 18754 if (decl) 18755 { 18756 init = build_tree_list (decl, init); 18757 TREE_CHAIN (init) = inits; 18758 inits = init; 18759 } 18760 } 18761 } 18762 return inits; 18763 } 18764 18765 /* Set CURRENT_ACCESS_SPECIFIER based on the protection of DECL. */ 18766 18767 static void 18768 set_current_access_from_decl (tree decl) 18769 { 18770 if (TREE_PRIVATE (decl)) 18771 current_access_specifier = access_private_node; 18772 else if (TREE_PROTECTED (decl)) 18773 current_access_specifier = access_protected_node; 18774 else 18775 current_access_specifier = access_public_node; 18776 } 18777 18778 /* Instantiate an enumerated type. TAG is the template type, NEWTAG 18779 is the instantiation (which should have been created with 18780 start_enum) and ARGS are the template arguments to use. */ 18781 18782 static void 18783 tsubst_enum (tree tag, tree newtag, tree args) 18784 { 18785 tree e; 18786 18787 if (SCOPED_ENUM_P (newtag)) 18788 begin_scope (sk_scoped_enum, newtag); 18789 18790 for (e = TYPE_VALUES (tag); e; e = TREE_CHAIN (e)) 18791 { 18792 tree value; 18793 tree decl; 18794 18795 decl = TREE_VALUE (e); 18796 /* Note that in a template enum, the TREE_VALUE is the 18797 CONST_DECL, not the corresponding INTEGER_CST. */ 18798 value = tsubst_expr (DECL_INITIAL (decl), 18799 args, tf_warning_or_error, NULL_TREE, 18800 /*integral_constant_expression_p=*/true); 18801 18802 /* Give this enumeration constant the correct access. */ 18803 set_current_access_from_decl (decl); 18804 18805 /* Actually build the enumerator itself. */ 18806 build_enumerator 18807 (DECL_NAME (decl), value, newtag, DECL_SOURCE_LOCATION (decl)); 18808 } 18809 18810 if (SCOPED_ENUM_P (newtag)) 18811 finish_scope (); 18812 18813 finish_enum_value_list (newtag); 18814 finish_enum (newtag); 18815 18816 DECL_SOURCE_LOCATION (TYPE_NAME (newtag)) 18817 = DECL_SOURCE_LOCATION (TYPE_NAME (tag)); 18818 } 18819 18820 /* DECL is a FUNCTION_DECL that is a template specialization. Return 18821 its type -- but without substituting the innermost set of template 18822 arguments. So, innermost set of template parameters will appear in 18823 the type. */ 18824 18825 tree 18826 get_mostly_instantiated_function_type (tree decl) 18827 { 18828 tree fn_type; 18829 tree tmpl; 18830 tree targs; 18831 tree tparms; 18832 int parm_depth; 18833 18834 tmpl = most_general_template (DECL_TI_TEMPLATE (decl)); 18835 targs = DECL_TI_ARGS (decl); 18836 tparms = DECL_TEMPLATE_PARMS (tmpl); 18837 parm_depth = TMPL_PARMS_DEPTH (tparms); 18838 18839 /* There should be as many levels of arguments as there are levels 18840 of parameters. */ 18841 gcc_assert (parm_depth == TMPL_ARGS_DEPTH (targs)); 18842 18843 fn_type = TREE_TYPE (tmpl); 18844 18845 if (parm_depth == 1) 18846 /* No substitution is necessary. */ 18847 ; 18848 else 18849 { 18850 int i; 18851 tree partial_args; 18852 18853 /* Replace the innermost level of the TARGS with NULL_TREEs to 18854 let tsubst know not to substitute for those parameters. */ 18855 partial_args = make_tree_vec (TREE_VEC_LENGTH (targs)); 18856 for (i = 1; i < TMPL_ARGS_DEPTH (targs); ++i) 18857 SET_TMPL_ARGS_LEVEL (partial_args, i, 18858 TMPL_ARGS_LEVEL (targs, i)); 18859 SET_TMPL_ARGS_LEVEL (partial_args, 18860 TMPL_ARGS_DEPTH (targs), 18861 make_tree_vec (DECL_NTPARMS (tmpl))); 18862 18863 /* Make sure that we can see identifiers, and compute access 18864 correctly. */ 18865 push_access_scope (decl); 18866 18867 ++processing_template_decl; 18868 /* Now, do the (partial) substitution to figure out the 18869 appropriate function type. */ 18870 fn_type = tsubst (fn_type, partial_args, tf_error, NULL_TREE); 18871 --processing_template_decl; 18872 18873 /* Substitute into the template parameters to obtain the real 18874 innermost set of parameters. This step is important if the 18875 innermost set of template parameters contains value 18876 parameters whose types depend on outer template parameters. */ 18877 TREE_VEC_LENGTH (partial_args)--; 18878 tparms = tsubst_template_parms (tparms, partial_args, tf_error); 18879 18880 pop_access_scope (decl); 18881 } 18882 18883 return fn_type; 18884 } 18885 18886 /* Return truthvalue if we're processing a template different from 18887 the last one involved in diagnostics. */ 18888 int 18889 problematic_instantiation_changed (void) 18890 { 18891 return current_tinst_level != last_error_tinst_level; 18892 } 18893 18894 /* Remember current template involved in diagnostics. */ 18895 void 18896 record_last_problematic_instantiation (void) 18897 { 18898 last_error_tinst_level = current_tinst_level; 18899 } 18900 18901 struct tinst_level * 18902 current_instantiation (void) 18903 { 18904 return current_tinst_level; 18905 } 18906 18907 /* [temp.param] Check that template non-type parm TYPE is of an allowable 18908 type. Return zero for ok, nonzero for disallowed. Issue error and 18909 warning messages under control of COMPLAIN. */ 18910 18911 static int 18912 invalid_nontype_parm_type_p (tree type, tsubst_flags_t complain) 18913 { 18914 if (INTEGRAL_OR_ENUMERATION_TYPE_P (type)) 18915 return 0; 18916 else if (POINTER_TYPE_P (type)) 18917 return 0; 18918 else if (TYPE_PTR_TO_MEMBER_P (type)) 18919 return 0; 18920 else if (TREE_CODE (type) == TEMPLATE_TYPE_PARM) 18921 return 0; 18922 else if (TREE_CODE (type) == TYPENAME_TYPE) 18923 return 0; 18924 else if (TREE_CODE (type) == DECLTYPE_TYPE) 18925 return 0; 18926 else if (TREE_CODE (type) == NULLPTR_TYPE) 18927 return 0; 18928 18929 if (complain & tf_error) 18930 { 18931 if (type == error_mark_node) 18932 inform (input_location, "invalid template non-type parameter"); 18933 else 18934 error ("%q#T is not a valid type for a template non-type parameter", 18935 type); 18936 } 18937 return 1; 18938 } 18939 18940 /* Returns TRUE if TYPE is dependent, in the sense of [temp.dep.type]. 18941 Assumes that TYPE really is a type, and not the ERROR_MARK_NODE.*/ 18942 18943 static bool 18944 dependent_type_p_r (tree type) 18945 { 18946 tree scope; 18947 18948 /* [temp.dep.type] 18949 18950 A type is dependent if it is: 18951 18952 -- a template parameter. Template template parameters are types 18953 for us (since TYPE_P holds true for them) so we handle 18954 them here. */ 18955 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM 18956 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM) 18957 return true; 18958 /* -- a qualified-id with a nested-name-specifier which contains a 18959 class-name that names a dependent type or whose unqualified-id 18960 names a dependent type. */ 18961 if (TREE_CODE (type) == TYPENAME_TYPE) 18962 return true; 18963 /* -- a cv-qualified type where the cv-unqualified type is 18964 dependent. */ 18965 type = TYPE_MAIN_VARIANT (type); 18966 /* -- a compound type constructed from any dependent type. */ 18967 if (TYPE_PTR_TO_MEMBER_P (type)) 18968 return (dependent_type_p (TYPE_PTRMEM_CLASS_TYPE (type)) 18969 || dependent_type_p (TYPE_PTRMEM_POINTED_TO_TYPE 18970 (type))); 18971 else if (TREE_CODE (type) == POINTER_TYPE 18972 || TREE_CODE (type) == REFERENCE_TYPE) 18973 return dependent_type_p (TREE_TYPE (type)); 18974 else if (TREE_CODE (type) == FUNCTION_TYPE 18975 || TREE_CODE (type) == METHOD_TYPE) 18976 { 18977 tree arg_type; 18978 18979 if (dependent_type_p (TREE_TYPE (type))) 18980 return true; 18981 for (arg_type = TYPE_ARG_TYPES (type); 18982 arg_type; 18983 arg_type = TREE_CHAIN (arg_type)) 18984 if (dependent_type_p (TREE_VALUE (arg_type))) 18985 return true; 18986 return false; 18987 } 18988 /* -- an array type constructed from any dependent type or whose 18989 size is specified by a constant expression that is 18990 value-dependent. 18991 18992 We checked for type- and value-dependence of the bounds in 18993 compute_array_index_type, so TYPE_DEPENDENT_P is already set. */ 18994 if (TREE_CODE (type) == ARRAY_TYPE) 18995 { 18996 if (TYPE_DOMAIN (type) 18997 && dependent_type_p (TYPE_DOMAIN (type))) 18998 return true; 18999 return dependent_type_p (TREE_TYPE (type)); 19000 } 19001 19002 /* -- a template-id in which either the template name is a template 19003 parameter ... */ 19004 if (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM) 19005 return true; 19006 /* ... or any of the template arguments is a dependent type or 19007 an expression that is type-dependent or value-dependent. */ 19008 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INFO (type) 19009 && (any_dependent_template_arguments_p 19010 (INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type))))) 19011 return true; 19012 19013 /* All TYPEOF_TYPEs, DECLTYPE_TYPEs, and UNDERLYING_TYPEs are 19014 dependent; if the argument of the `typeof' expression is not 19015 type-dependent, then it should already been have resolved. */ 19016 if (TREE_CODE (type) == TYPEOF_TYPE 19017 || TREE_CODE (type) == DECLTYPE_TYPE 19018 || TREE_CODE (type) == UNDERLYING_TYPE) 19019 return true; 19020 19021 /* A template argument pack is dependent if any of its packed 19022 arguments are. */ 19023 if (TREE_CODE (type) == TYPE_ARGUMENT_PACK) 19024 { 19025 tree args = ARGUMENT_PACK_ARGS (type); 19026 int i, len = TREE_VEC_LENGTH (args); 19027 for (i = 0; i < len; ++i) 19028 if (dependent_template_arg_p (TREE_VEC_ELT (args, i))) 19029 return true; 19030 } 19031 19032 /* All TYPE_PACK_EXPANSIONs are dependent, because parameter packs must 19033 be template parameters. */ 19034 if (TREE_CODE (type) == TYPE_PACK_EXPANSION) 19035 return true; 19036 19037 /* The standard does not specifically mention types that are local 19038 to template functions or local classes, but they should be 19039 considered dependent too. For example: 19040 19041 template <int I> void f() { 19042 enum E { a = I }; 19043 S<sizeof (E)> s; 19044 } 19045 19046 The size of `E' cannot be known until the value of `I' has been 19047 determined. Therefore, `E' must be considered dependent. */ 19048 scope = TYPE_CONTEXT (type); 19049 if (scope && TYPE_P (scope)) 19050 return dependent_type_p (scope); 19051 /* Don't use type_dependent_expression_p here, as it can lead 19052 to infinite recursion trying to determine whether a lambda 19053 nested in a lambda is dependent (c++/47687). */ 19054 else if (scope && TREE_CODE (scope) == FUNCTION_DECL 19055 && DECL_LANG_SPECIFIC (scope) 19056 && DECL_TEMPLATE_INFO (scope) 19057 && (any_dependent_template_arguments_p 19058 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (scope))))) 19059 return true; 19060 19061 /* Other types are non-dependent. */ 19062 return false; 19063 } 19064 19065 /* Returns TRUE if TYPE is dependent, in the sense of 19066 [temp.dep.type]. Note that a NULL type is considered dependent. */ 19067 19068 bool 19069 dependent_type_p (tree type) 19070 { 19071 /* If there are no template parameters in scope, then there can't be 19072 any dependent types. */ 19073 if (!processing_template_decl) 19074 { 19075 /* If we are not processing a template, then nobody should be 19076 providing us with a dependent type. */ 19077 gcc_assert (type); 19078 gcc_assert (TREE_CODE (type) != TEMPLATE_TYPE_PARM || is_auto (type)); 19079 return false; 19080 } 19081 19082 /* If the type is NULL, we have not computed a type for the entity 19083 in question; in that case, the type is dependent. */ 19084 if (!type) 19085 return true; 19086 19087 /* Erroneous types can be considered non-dependent. */ 19088 if (type == error_mark_node) 19089 return false; 19090 19091 /* If we have not already computed the appropriate value for TYPE, 19092 do so now. */ 19093 if (!TYPE_DEPENDENT_P_VALID (type)) 19094 { 19095 TYPE_DEPENDENT_P (type) = dependent_type_p_r (type); 19096 TYPE_DEPENDENT_P_VALID (type) = 1; 19097 } 19098 19099 return TYPE_DEPENDENT_P (type); 19100 } 19101 19102 /* Returns TRUE if SCOPE is a dependent scope, in which we can't do any 19103 lookup. In other words, a dependent type that is not the current 19104 instantiation. */ 19105 19106 bool 19107 dependent_scope_p (tree scope) 19108 { 19109 return (scope && TYPE_P (scope) && dependent_type_p (scope) 19110 && !currently_open_class (scope)); 19111 } 19112 19113 /* Returns TRUE if the EXPRESSION is value-dependent, in the sense of 19114 [temp.dep.constexpr]. EXPRESSION is already known to be a constant 19115 expression. */ 19116 19117 /* Note that this predicate is not appropriate for general expressions; 19118 only constant expressions (that satisfy potential_constant_expression) 19119 can be tested for value dependence. 19120 19121 We should really also have a predicate for "instantiation-dependent". 19122 19123 fold_non_dependent_expr: fold if constant and not type-dependent and not value-dependent. 19124 (what about instantiation-dependent constant-expressions?) 19125 is_late_template_attribute: defer if instantiation-dependent. 19126 compute_array_index_type: proceed if constant and not t- or v-dependent 19127 if instantiation-dependent, need to remember full expression 19128 uses_template_parms: FIXME - need to audit callers 19129 tsubst_decl [function_decl]: Why is this using value_dependent_expression_p? 19130 dependent_type_p [array_type]: dependent if index type is dependent 19131 (or non-constant?) 19132 static_assert - instantiation-dependent */ 19133 19134 bool 19135 value_dependent_expression_p (tree expression) 19136 { 19137 if (!processing_template_decl) 19138 return false; 19139 19140 /* A name declared with a dependent type. */ 19141 if (DECL_P (expression) && type_dependent_expression_p (expression)) 19142 return true; 19143 19144 switch (TREE_CODE (expression)) 19145 { 19146 case IDENTIFIER_NODE: 19147 /* A name that has not been looked up -- must be dependent. */ 19148 return true; 19149 19150 case TEMPLATE_PARM_INDEX: 19151 /* A non-type template parm. */ 19152 return true; 19153 19154 case CONST_DECL: 19155 /* A non-type template parm. */ 19156 if (DECL_TEMPLATE_PARM_P (expression)) 19157 return true; 19158 return value_dependent_expression_p (DECL_INITIAL (expression)); 19159 19160 case VAR_DECL: 19161 /* A constant with literal type and is initialized 19162 with an expression that is value-dependent. 19163 19164 Note that a non-dependent parenthesized initializer will have 19165 already been replaced with its constant value, so if we see 19166 a TREE_LIST it must be dependent. */ 19167 if (DECL_INITIAL (expression) 19168 && decl_constant_var_p (expression) 19169 && (TREE_CODE (DECL_INITIAL (expression)) == TREE_LIST 19170 || value_dependent_expression_p (DECL_INITIAL (expression)))) 19171 return true; 19172 return false; 19173 19174 case DYNAMIC_CAST_EXPR: 19175 case STATIC_CAST_EXPR: 19176 case CONST_CAST_EXPR: 19177 case REINTERPRET_CAST_EXPR: 19178 case CAST_EXPR: 19179 /* These expressions are value-dependent if the type to which 19180 the cast occurs is dependent or the expression being casted 19181 is value-dependent. */ 19182 { 19183 tree type = TREE_TYPE (expression); 19184 19185 if (dependent_type_p (type)) 19186 return true; 19187 19188 /* A functional cast has a list of operands. */ 19189 expression = TREE_OPERAND (expression, 0); 19190 if (!expression) 19191 { 19192 /* If there are no operands, it must be an expression such 19193 as "int()". This should not happen for aggregate types 19194 because it would form non-constant expressions. */ 19195 gcc_assert (cxx_dialect >= cxx0x 19196 || INTEGRAL_OR_ENUMERATION_TYPE_P (type)); 19197 19198 return false; 19199 } 19200 19201 if (TREE_CODE (expression) == TREE_LIST) 19202 return any_value_dependent_elements_p (expression); 19203 19204 return value_dependent_expression_p (expression); 19205 } 19206 19207 case SIZEOF_EXPR: 19208 case ALIGNOF_EXPR: 19209 case TYPEID_EXPR: 19210 /* A `sizeof' expression is value-dependent if the operand is 19211 type-dependent or is a pack expansion. */ 19212 expression = TREE_OPERAND (expression, 0); 19213 if (PACK_EXPANSION_P (expression)) 19214 return true; 19215 else if (TYPE_P (expression)) 19216 return dependent_type_p (expression); 19217 return type_dependent_expression_p (expression); 19218 19219 case AT_ENCODE_EXPR: 19220 /* An 'encode' expression is value-dependent if the operand is 19221 type-dependent. */ 19222 expression = TREE_OPERAND (expression, 0); 19223 return dependent_type_p (expression); 19224 19225 case NOEXCEPT_EXPR: 19226 expression = TREE_OPERAND (expression, 0); 19227 return type_dependent_expression_p (expression); 19228 19229 case SCOPE_REF: 19230 { 19231 tree name = TREE_OPERAND (expression, 1); 19232 return value_dependent_expression_p (name); 19233 } 19234 19235 case COMPONENT_REF: 19236 return (value_dependent_expression_p (TREE_OPERAND (expression, 0)) 19237 || value_dependent_expression_p (TREE_OPERAND (expression, 1))); 19238 19239 case NONTYPE_ARGUMENT_PACK: 19240 /* A NONTYPE_ARGUMENT_PACK is value-dependent if any packed argument 19241 is value-dependent. */ 19242 { 19243 tree values = ARGUMENT_PACK_ARGS (expression); 19244 int i, len = TREE_VEC_LENGTH (values); 19245 19246 for (i = 0; i < len; ++i) 19247 if (value_dependent_expression_p (TREE_VEC_ELT (values, i))) 19248 return true; 19249 19250 return false; 19251 } 19252 19253 case TRAIT_EXPR: 19254 { 19255 tree type2 = TRAIT_EXPR_TYPE2 (expression); 19256 return (dependent_type_p (TRAIT_EXPR_TYPE1 (expression)) 19257 || (type2 ? dependent_type_p (type2) : false)); 19258 } 19259 19260 case MODOP_EXPR: 19261 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0))) 19262 || (value_dependent_expression_p (TREE_OPERAND (expression, 2)))); 19263 19264 case ARRAY_REF: 19265 return ((value_dependent_expression_p (TREE_OPERAND (expression, 0))) 19266 || (value_dependent_expression_p (TREE_OPERAND (expression, 1)))); 19267 19268 case ADDR_EXPR: 19269 { 19270 tree op = TREE_OPERAND (expression, 0); 19271 return (value_dependent_expression_p (op) 19272 || has_value_dependent_address (op)); 19273 } 19274 19275 case CALL_EXPR: 19276 { 19277 tree fn = get_callee_fndecl (expression); 19278 int i, nargs; 19279 if (!fn && value_dependent_expression_p (CALL_EXPR_FN (expression))) 19280 return true; 19281 nargs = call_expr_nargs (expression); 19282 for (i = 0; i < nargs; ++i) 19283 { 19284 tree op = CALL_EXPR_ARG (expression, i); 19285 /* In a call to a constexpr member function, look through the 19286 implicit ADDR_EXPR on the object argument so that it doesn't 19287 cause the call to be considered value-dependent. We also 19288 look through it in potential_constant_expression. */ 19289 if (i == 0 && fn && DECL_DECLARED_CONSTEXPR_P (fn) 19290 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn) 19291 && TREE_CODE (op) == ADDR_EXPR) 19292 op = TREE_OPERAND (op, 0); 19293 if (value_dependent_expression_p (op)) 19294 return true; 19295 } 19296 return false; 19297 } 19298 19299 case TEMPLATE_ID_EXPR: 19300 /* If a TEMPLATE_ID_EXPR involves a dependent name, it will be 19301 type-dependent. */ 19302 return type_dependent_expression_p (expression); 19303 19304 case CONSTRUCTOR: 19305 { 19306 unsigned ix; 19307 tree val; 19308 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), ix, val) 19309 if (value_dependent_expression_p (val)) 19310 return true; 19311 return false; 19312 } 19313 19314 case STMT_EXPR: 19315 /* Treat a GNU statement expression as dependent to avoid crashing 19316 under fold_non_dependent_expr; it can't be constant. */ 19317 return true; 19318 19319 default: 19320 /* A constant expression is value-dependent if any subexpression is 19321 value-dependent. */ 19322 switch (TREE_CODE_CLASS (TREE_CODE (expression))) 19323 { 19324 case tcc_reference: 19325 case tcc_unary: 19326 case tcc_comparison: 19327 case tcc_binary: 19328 case tcc_expression: 19329 case tcc_vl_exp: 19330 { 19331 int i, len = cp_tree_operand_length (expression); 19332 19333 for (i = 0; i < len; i++) 19334 { 19335 tree t = TREE_OPERAND (expression, i); 19336 19337 /* In some cases, some of the operands may be missing.l 19338 (For example, in the case of PREDECREMENT_EXPR, the 19339 amount to increment by may be missing.) That doesn't 19340 make the expression dependent. */ 19341 if (t && value_dependent_expression_p (t)) 19342 return true; 19343 } 19344 } 19345 break; 19346 default: 19347 break; 19348 } 19349 break; 19350 } 19351 19352 /* The expression is not value-dependent. */ 19353 return false; 19354 } 19355 19356 /* Returns TRUE if the EXPRESSION is type-dependent, in the sense of 19357 [temp.dep.expr]. Note that an expression with no type is 19358 considered dependent. Other parts of the compiler arrange for an 19359 expression with type-dependent subexpressions to have no type, so 19360 this function doesn't have to be fully recursive. */ 19361 19362 bool 19363 type_dependent_expression_p (tree expression) 19364 { 19365 if (!processing_template_decl) 19366 return false; 19367 19368 if (expression == error_mark_node) 19369 return false; 19370 19371 /* An unresolved name is always dependent. */ 19372 if (TREE_CODE (expression) == IDENTIFIER_NODE 19373 || TREE_CODE (expression) == USING_DECL) 19374 return true; 19375 19376 /* Some expression forms are never type-dependent. */ 19377 if (TREE_CODE (expression) == PSEUDO_DTOR_EXPR 19378 || TREE_CODE (expression) == SIZEOF_EXPR 19379 || TREE_CODE (expression) == ALIGNOF_EXPR 19380 || TREE_CODE (expression) == AT_ENCODE_EXPR 19381 || TREE_CODE (expression) == NOEXCEPT_EXPR 19382 || TREE_CODE (expression) == TRAIT_EXPR 19383 || TREE_CODE (expression) == TYPEID_EXPR 19384 || TREE_CODE (expression) == DELETE_EXPR 19385 || TREE_CODE (expression) == VEC_DELETE_EXPR 19386 || TREE_CODE (expression) == THROW_EXPR) 19387 return false; 19388 19389 /* The types of these expressions depends only on the type to which 19390 the cast occurs. */ 19391 if (TREE_CODE (expression) == DYNAMIC_CAST_EXPR 19392 || TREE_CODE (expression) == STATIC_CAST_EXPR 19393 || TREE_CODE (expression) == CONST_CAST_EXPR 19394 || TREE_CODE (expression) == REINTERPRET_CAST_EXPR 19395 || TREE_CODE (expression) == IMPLICIT_CONV_EXPR 19396 || TREE_CODE (expression) == CAST_EXPR) 19397 return dependent_type_p (TREE_TYPE (expression)); 19398 19399 /* The types of these expressions depends only on the type created 19400 by the expression. */ 19401 if (TREE_CODE (expression) == NEW_EXPR 19402 || TREE_CODE (expression) == VEC_NEW_EXPR) 19403 { 19404 /* For NEW_EXPR tree nodes created inside a template, either 19405 the object type itself or a TREE_LIST may appear as the 19406 operand 1. */ 19407 tree type = TREE_OPERAND (expression, 1); 19408 if (TREE_CODE (type) == TREE_LIST) 19409 /* This is an array type. We need to check array dimensions 19410 as well. */ 19411 return dependent_type_p (TREE_VALUE (TREE_PURPOSE (type))) 19412 || value_dependent_expression_p 19413 (TREE_OPERAND (TREE_VALUE (type), 1)); 19414 else 19415 return dependent_type_p (type); 19416 } 19417 19418 if (TREE_CODE (expression) == SCOPE_REF) 19419 { 19420 tree scope = TREE_OPERAND (expression, 0); 19421 tree name = TREE_OPERAND (expression, 1); 19422 19423 /* 14.6.2.2 [temp.dep.expr]: An id-expression is type-dependent if it 19424 contains an identifier associated by name lookup with one or more 19425 declarations declared with a dependent type, or...a 19426 nested-name-specifier or qualified-id that names a member of an 19427 unknown specialization. */ 19428 return (type_dependent_expression_p (name) 19429 || dependent_scope_p (scope)); 19430 } 19431 19432 if (TREE_CODE (expression) == FUNCTION_DECL 19433 && DECL_LANG_SPECIFIC (expression) 19434 && DECL_TEMPLATE_INFO (expression) 19435 && (any_dependent_template_arguments_p 19436 (INNERMOST_TEMPLATE_ARGS (DECL_TI_ARGS (expression))))) 19437 return true; 19438 19439 if (TREE_CODE (expression) == TEMPLATE_DECL 19440 && !DECL_TEMPLATE_TEMPLATE_PARM_P (expression)) 19441 return false; 19442 19443 if (TREE_CODE (expression) == STMT_EXPR) 19444 expression = stmt_expr_value_expr (expression); 19445 19446 if (BRACE_ENCLOSED_INITIALIZER_P (expression)) 19447 { 19448 tree elt; 19449 unsigned i; 19450 19451 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (expression), i, elt) 19452 { 19453 if (type_dependent_expression_p (elt)) 19454 return true; 19455 } 19456 return false; 19457 } 19458 19459 /* A static data member of the current instantiation with incomplete 19460 array type is type-dependent, as the definition and specializations 19461 can have different bounds. */ 19462 if (TREE_CODE (expression) == VAR_DECL 19463 && DECL_CLASS_SCOPE_P (expression) 19464 && dependent_type_p (DECL_CONTEXT (expression)) 19465 && VAR_HAD_UNKNOWN_BOUND (expression)) 19466 return true; 19467 19468 if (TREE_TYPE (expression) == unknown_type_node) 19469 { 19470 if (TREE_CODE (expression) == ADDR_EXPR) 19471 return type_dependent_expression_p (TREE_OPERAND (expression, 0)); 19472 if (TREE_CODE (expression) == COMPONENT_REF 19473 || TREE_CODE (expression) == OFFSET_REF) 19474 { 19475 if (type_dependent_expression_p (TREE_OPERAND (expression, 0))) 19476 return true; 19477 expression = TREE_OPERAND (expression, 1); 19478 if (TREE_CODE (expression) == IDENTIFIER_NODE) 19479 return false; 19480 } 19481 /* SCOPE_REF with non-null TREE_TYPE is always non-dependent. */ 19482 if (TREE_CODE (expression) == SCOPE_REF) 19483 return false; 19484 19485 if (BASELINK_P (expression)) 19486 expression = BASELINK_FUNCTIONS (expression); 19487 19488 if (TREE_CODE (expression) == TEMPLATE_ID_EXPR) 19489 { 19490 if (any_dependent_template_arguments_p 19491 (TREE_OPERAND (expression, 1))) 19492 return true; 19493 expression = TREE_OPERAND (expression, 0); 19494 } 19495 gcc_assert (TREE_CODE (expression) == OVERLOAD 19496 || TREE_CODE (expression) == FUNCTION_DECL); 19497 19498 while (expression) 19499 { 19500 if (type_dependent_expression_p (OVL_CURRENT (expression))) 19501 return true; 19502 expression = OVL_NEXT (expression); 19503 } 19504 return false; 19505 } 19506 19507 gcc_assert (TREE_CODE (expression) != TYPE_DECL); 19508 19509 return (dependent_type_p (TREE_TYPE (expression))); 19510 } 19511 19512 /* Like type_dependent_expression_p, but it also works while not processing 19513 a template definition, i.e. during substitution or mangling. */ 19514 19515 bool 19516 type_dependent_expression_p_push (tree expr) 19517 { 19518 bool b; 19519 ++processing_template_decl; 19520 b = type_dependent_expression_p (expr); 19521 --processing_template_decl; 19522 return b; 19523 } 19524 19525 /* Returns TRUE if ARGS contains a type-dependent expression. */ 19526 19527 bool 19528 any_type_dependent_arguments_p (const VEC(tree,gc) *args) 19529 { 19530 unsigned int i; 19531 tree arg; 19532 19533 FOR_EACH_VEC_ELT (tree, args, i, arg) 19534 { 19535 if (type_dependent_expression_p (arg)) 19536 return true; 19537 } 19538 return false; 19539 } 19540 19541 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are 19542 expressions) contains any type-dependent expressions. */ 19543 19544 bool 19545 any_type_dependent_elements_p (const_tree list) 19546 { 19547 for (; list; list = TREE_CHAIN (list)) 19548 if (value_dependent_expression_p (TREE_VALUE (list))) 19549 return true; 19550 19551 return false; 19552 } 19553 19554 /* Returns TRUE if LIST (a TREE_LIST whose TREE_VALUEs are 19555 expressions) contains any value-dependent expressions. */ 19556 19557 bool 19558 any_value_dependent_elements_p (const_tree list) 19559 { 19560 for (; list; list = TREE_CHAIN (list)) 19561 if (value_dependent_expression_p (TREE_VALUE (list))) 19562 return true; 19563 19564 return false; 19565 } 19566 19567 /* Returns TRUE if the ARG (a template argument) is dependent. */ 19568 19569 bool 19570 dependent_template_arg_p (tree arg) 19571 { 19572 if (!processing_template_decl) 19573 return false; 19574 19575 /* Assume a template argument that was wrongly written by the user 19576 is dependent. This is consistent with what 19577 any_dependent_template_arguments_p [that calls this function] 19578 does. */ 19579 if (!arg || arg == error_mark_node) 19580 return true; 19581 19582 if (TREE_CODE (arg) == ARGUMENT_PACK_SELECT) 19583 arg = ARGUMENT_PACK_SELECT_ARG (arg); 19584 19585 if (TREE_CODE (arg) == TEMPLATE_DECL 19586 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM) 19587 return dependent_template_p (arg); 19588 else if (ARGUMENT_PACK_P (arg)) 19589 { 19590 tree args = ARGUMENT_PACK_ARGS (arg); 19591 int i, len = TREE_VEC_LENGTH (args); 19592 for (i = 0; i < len; ++i) 19593 { 19594 if (dependent_template_arg_p (TREE_VEC_ELT (args, i))) 19595 return true; 19596 } 19597 19598 return false; 19599 } 19600 else if (TYPE_P (arg)) 19601 return dependent_type_p (arg); 19602 else 19603 return (type_dependent_expression_p (arg) 19604 || value_dependent_expression_p (arg)); 19605 } 19606 19607 /* Returns true if ARGS (a collection of template arguments) contains 19608 any types that require structural equality testing. */ 19609 19610 bool 19611 any_template_arguments_need_structural_equality_p (tree args) 19612 { 19613 int i; 19614 int j; 19615 19616 if (!args) 19617 return false; 19618 if (args == error_mark_node) 19619 return true; 19620 19621 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i) 19622 { 19623 tree level = TMPL_ARGS_LEVEL (args, i + 1); 19624 for (j = 0; j < TREE_VEC_LENGTH (level); ++j) 19625 { 19626 tree arg = TREE_VEC_ELT (level, j); 19627 tree packed_args = NULL_TREE; 19628 int k, len = 1; 19629 19630 if (ARGUMENT_PACK_P (arg)) 19631 { 19632 /* Look inside the argument pack. */ 19633 packed_args = ARGUMENT_PACK_ARGS (arg); 19634 len = TREE_VEC_LENGTH (packed_args); 19635 } 19636 19637 for (k = 0; k < len; ++k) 19638 { 19639 if (packed_args) 19640 arg = TREE_VEC_ELT (packed_args, k); 19641 19642 if (error_operand_p (arg)) 19643 return true; 19644 else if (TREE_CODE (arg) == TEMPLATE_DECL 19645 || TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM) 19646 continue; 19647 else if (TYPE_P (arg) && TYPE_STRUCTURAL_EQUALITY_P (arg)) 19648 return true; 19649 else if (!TYPE_P (arg) && TREE_TYPE (arg) 19650 && TYPE_STRUCTURAL_EQUALITY_P (TREE_TYPE (arg))) 19651 return true; 19652 } 19653 } 19654 } 19655 19656 return false; 19657 } 19658 19659 /* Returns true if ARGS (a collection of template arguments) contains 19660 any dependent arguments. */ 19661 19662 bool 19663 any_dependent_template_arguments_p (const_tree args) 19664 { 19665 int i; 19666 int j; 19667 19668 if (!args) 19669 return false; 19670 if (args == error_mark_node) 19671 return true; 19672 19673 for (i = 0; i < TMPL_ARGS_DEPTH (args); ++i) 19674 { 19675 const_tree level = TMPL_ARGS_LEVEL (args, i + 1); 19676 for (j = 0; j < TREE_VEC_LENGTH (level); ++j) 19677 if (dependent_template_arg_p (TREE_VEC_ELT (level, j))) 19678 return true; 19679 } 19680 19681 return false; 19682 } 19683 19684 /* Returns TRUE if the template TMPL is dependent. */ 19685 19686 bool 19687 dependent_template_p (tree tmpl) 19688 { 19689 if (TREE_CODE (tmpl) == OVERLOAD) 19690 { 19691 while (tmpl) 19692 { 19693 if (dependent_template_p (OVL_CURRENT (tmpl))) 19694 return true; 19695 tmpl = OVL_NEXT (tmpl); 19696 } 19697 return false; 19698 } 19699 19700 /* Template template parameters are dependent. */ 19701 if (DECL_TEMPLATE_TEMPLATE_PARM_P (tmpl) 19702 || TREE_CODE (tmpl) == TEMPLATE_TEMPLATE_PARM) 19703 return true; 19704 /* So are names that have not been looked up. */ 19705 if (TREE_CODE (tmpl) == SCOPE_REF 19706 || TREE_CODE (tmpl) == IDENTIFIER_NODE) 19707 return true; 19708 /* So are member templates of dependent classes. */ 19709 if (TYPE_P (CP_DECL_CONTEXT (tmpl))) 19710 return dependent_type_p (DECL_CONTEXT (tmpl)); 19711 return false; 19712 } 19713 19714 /* Returns TRUE if the specialization TMPL<ARGS> is dependent. */ 19715 19716 bool 19717 dependent_template_id_p (tree tmpl, tree args) 19718 { 19719 return (dependent_template_p (tmpl) 19720 || any_dependent_template_arguments_p (args)); 19721 } 19722 19723 /* Returns TRUE if OMP_FOR with DECLV, INITV, CONDV and INCRV vectors 19724 is dependent. */ 19725 19726 bool 19727 dependent_omp_for_p (tree declv, tree initv, tree condv, tree incrv) 19728 { 19729 int i; 19730 19731 if (!processing_template_decl) 19732 return false; 19733 19734 for (i = 0; i < TREE_VEC_LENGTH (declv); i++) 19735 { 19736 tree decl = TREE_VEC_ELT (declv, i); 19737 tree init = TREE_VEC_ELT (initv, i); 19738 tree cond = TREE_VEC_ELT (condv, i); 19739 tree incr = TREE_VEC_ELT (incrv, i); 19740 19741 if (type_dependent_expression_p (decl)) 19742 return true; 19743 19744 if (init && type_dependent_expression_p (init)) 19745 return true; 19746 19747 if (type_dependent_expression_p (cond)) 19748 return true; 19749 19750 if (COMPARISON_CLASS_P (cond) 19751 && (type_dependent_expression_p (TREE_OPERAND (cond, 0)) 19752 || type_dependent_expression_p (TREE_OPERAND (cond, 1)))) 19753 return true; 19754 19755 if (TREE_CODE (incr) == MODOP_EXPR) 19756 { 19757 if (type_dependent_expression_p (TREE_OPERAND (incr, 0)) 19758 || type_dependent_expression_p (TREE_OPERAND (incr, 2))) 19759 return true; 19760 } 19761 else if (type_dependent_expression_p (incr)) 19762 return true; 19763 else if (TREE_CODE (incr) == MODIFY_EXPR) 19764 { 19765 if (type_dependent_expression_p (TREE_OPERAND (incr, 0))) 19766 return true; 19767 else if (BINARY_CLASS_P (TREE_OPERAND (incr, 1))) 19768 { 19769 tree t = TREE_OPERAND (incr, 1); 19770 if (type_dependent_expression_p (TREE_OPERAND (t, 0)) 19771 || type_dependent_expression_p (TREE_OPERAND (t, 1))) 19772 return true; 19773 } 19774 } 19775 } 19776 19777 return false; 19778 } 19779 19780 /* TYPE is a TYPENAME_TYPE. Returns the ordinary TYPE to which the 19781 TYPENAME_TYPE corresponds. Returns the original TYPENAME_TYPE if 19782 no such TYPE can be found. Note that this function peers inside 19783 uninstantiated templates and therefore should be used only in 19784 extremely limited situations. ONLY_CURRENT_P restricts this 19785 peering to the currently open classes hierarchy (which is required 19786 when comparing types). */ 19787 19788 tree 19789 resolve_typename_type (tree type, bool only_current_p) 19790 { 19791 tree scope; 19792 tree name; 19793 tree decl; 19794 int quals; 19795 tree pushed_scope; 19796 tree result; 19797 19798 gcc_assert (TREE_CODE (type) == TYPENAME_TYPE); 19799 19800 scope = TYPE_CONTEXT (type); 19801 /* Usually the non-qualified identifier of a TYPENAME_TYPE is 19802 TYPE_IDENTIFIER (type). But when 'type' is a typedef variant of 19803 a TYPENAME_TYPE node, then TYPE_NAME (type) is set to the TYPE_DECL representing 19804 the typedef. In that case TYPE_IDENTIFIER (type) is not the non-qualified 19805 identifier of the TYPENAME_TYPE anymore. 19806 So by getting the TYPE_IDENTIFIER of the _main declaration_ of the 19807 TYPENAME_TYPE instead, we avoid messing up with a possible 19808 typedef variant case. */ 19809 name = TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type)); 19810 19811 /* If the SCOPE is itself a TYPENAME_TYPE, then we need to resolve 19812 it first before we can figure out what NAME refers to. */ 19813 if (TREE_CODE (scope) == TYPENAME_TYPE) 19814 { 19815 if (TYPENAME_IS_RESOLVING_P (scope)) 19816 /* Given a class template A with a dependent base with nested type C, 19817 typedef typename A::C::C C will land us here, as trying to resolve 19818 the initial A::C leads to the local C typedef, which leads back to 19819 A::C::C. So we break the recursion now. */ 19820 return type; 19821 else 19822 scope = resolve_typename_type (scope, only_current_p); 19823 } 19824 /* If we don't know what SCOPE refers to, then we cannot resolve the 19825 TYPENAME_TYPE. */ 19826 if (TREE_CODE (scope) == TYPENAME_TYPE) 19827 return type; 19828 /* If the SCOPE is a template type parameter, we have no way of 19829 resolving the name. */ 19830 if (TREE_CODE (scope) == TEMPLATE_TYPE_PARM) 19831 return type; 19832 /* If the SCOPE is not the current instantiation, there's no reason 19833 to look inside it. */ 19834 if (only_current_p && !currently_open_class (scope)) 19835 return type; 19836 /* If this is a typedef, we don't want to look inside (c++/11987). */ 19837 if (typedef_variant_p (type)) 19838 return type; 19839 /* If SCOPE isn't the template itself, it will not have a valid 19840 TYPE_FIELDS list. */ 19841 if (same_type_p (scope, CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope))) 19842 /* scope is either the template itself or a compatible instantiation 19843 like X<T>, so look up the name in the original template. */ 19844 scope = CLASSTYPE_PRIMARY_TEMPLATE_TYPE (scope); 19845 else 19846 /* scope is a partial instantiation, so we can't do the lookup or we 19847 will lose the template arguments. */ 19848 return type; 19849 /* Enter the SCOPE so that name lookup will be resolved as if we 19850 were in the class definition. In particular, SCOPE will no 19851 longer be considered a dependent type. */ 19852 pushed_scope = push_scope (scope); 19853 /* Look up the declaration. */ 19854 decl = lookup_member (scope, name, /*protect=*/0, /*want_type=*/true, 19855 tf_warning_or_error); 19856 19857 result = NULL_TREE; 19858 19859 /* For a TYPENAME_TYPE like "typename X::template Y<T>", we want to 19860 find a TEMPLATE_DECL. Otherwise, we want to find a TYPE_DECL. */ 19861 if (!decl) 19862 /*nop*/; 19863 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == IDENTIFIER_NODE 19864 && TREE_CODE (decl) == TYPE_DECL) 19865 { 19866 result = TREE_TYPE (decl); 19867 if (result == error_mark_node) 19868 result = NULL_TREE; 19869 } 19870 else if (TREE_CODE (TYPENAME_TYPE_FULLNAME (type)) == TEMPLATE_ID_EXPR 19871 && DECL_CLASS_TEMPLATE_P (decl)) 19872 { 19873 tree tmpl; 19874 tree args; 19875 /* Obtain the template and the arguments. */ 19876 tmpl = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 0); 19877 args = TREE_OPERAND (TYPENAME_TYPE_FULLNAME (type), 1); 19878 /* Instantiate the template. */ 19879 result = lookup_template_class (tmpl, args, NULL_TREE, NULL_TREE, 19880 /*entering_scope=*/0, 19881 tf_error | tf_user); 19882 if (result == error_mark_node) 19883 result = NULL_TREE; 19884 } 19885 19886 /* Leave the SCOPE. */ 19887 if (pushed_scope) 19888 pop_scope (pushed_scope); 19889 19890 /* If we failed to resolve it, return the original typename. */ 19891 if (!result) 19892 return type; 19893 19894 /* If lookup found a typename type, resolve that too. */ 19895 if (TREE_CODE (result) == TYPENAME_TYPE && !TYPENAME_IS_RESOLVING_P (result)) 19896 { 19897 /* Ill-formed programs can cause infinite recursion here, so we 19898 must catch that. */ 19899 TYPENAME_IS_RESOLVING_P (type) = 1; 19900 result = resolve_typename_type (result, only_current_p); 19901 TYPENAME_IS_RESOLVING_P (type) = 0; 19902 } 19903 19904 /* Qualify the resulting type. */ 19905 quals = cp_type_quals (type); 19906 if (quals) 19907 result = cp_build_qualified_type (result, cp_type_quals (result) | quals); 19908 19909 return result; 19910 } 19911 19912 /* EXPR is an expression which is not type-dependent. Return a proxy 19913 for EXPR that can be used to compute the types of larger 19914 expressions containing EXPR. */ 19915 19916 tree 19917 build_non_dependent_expr (tree expr) 19918 { 19919 tree inner_expr; 19920 19921 #ifdef ENABLE_CHECKING 19922 /* Try to get a constant value for all non-type-dependent expressions in 19923 order to expose bugs in *_dependent_expression_p and constexpr. */ 19924 if (cxx_dialect >= cxx0x) 19925 maybe_constant_value (fold_non_dependent_expr_sfinae (expr, tf_none)); 19926 #endif 19927 19928 /* Preserve OVERLOADs; the functions must be available to resolve 19929 types. */ 19930 inner_expr = expr; 19931 if (TREE_CODE (inner_expr) == STMT_EXPR) 19932 inner_expr = stmt_expr_value_expr (inner_expr); 19933 if (TREE_CODE (inner_expr) == ADDR_EXPR) 19934 inner_expr = TREE_OPERAND (inner_expr, 0); 19935 if (TREE_CODE (inner_expr) == COMPONENT_REF) 19936 inner_expr = TREE_OPERAND (inner_expr, 1); 19937 if (is_overloaded_fn (inner_expr) 19938 || TREE_CODE (inner_expr) == OFFSET_REF) 19939 return expr; 19940 /* There is no need to return a proxy for a variable. */ 19941 if (TREE_CODE (expr) == VAR_DECL) 19942 return expr; 19943 /* Preserve string constants; conversions from string constants to 19944 "char *" are allowed, even though normally a "const char *" 19945 cannot be used to initialize a "char *". */ 19946 if (TREE_CODE (expr) == STRING_CST) 19947 return expr; 19948 /* Preserve arithmetic constants, as an optimization -- there is no 19949 reason to create a new node. */ 19950 if (TREE_CODE (expr) == INTEGER_CST || TREE_CODE (expr) == REAL_CST) 19951 return expr; 19952 /* Preserve THROW_EXPRs -- all throw-expressions have type "void". 19953 There is at least one place where we want to know that a 19954 particular expression is a throw-expression: when checking a ?: 19955 expression, there are special rules if the second or third 19956 argument is a throw-expression. */ 19957 if (TREE_CODE (expr) == THROW_EXPR) 19958 return expr; 19959 19960 /* Don't wrap an initializer list, we need to be able to look inside. */ 19961 if (BRACE_ENCLOSED_INITIALIZER_P (expr)) 19962 return expr; 19963 19964 if (TREE_CODE (expr) == COND_EXPR) 19965 return build3 (COND_EXPR, 19966 TREE_TYPE (expr), 19967 TREE_OPERAND (expr, 0), 19968 (TREE_OPERAND (expr, 1) 19969 ? build_non_dependent_expr (TREE_OPERAND (expr, 1)) 19970 : build_non_dependent_expr (TREE_OPERAND (expr, 0))), 19971 build_non_dependent_expr (TREE_OPERAND (expr, 2))); 19972 if (TREE_CODE (expr) == COMPOUND_EXPR 19973 && !COMPOUND_EXPR_OVERLOADED (expr)) 19974 return build2 (COMPOUND_EXPR, 19975 TREE_TYPE (expr), 19976 TREE_OPERAND (expr, 0), 19977 build_non_dependent_expr (TREE_OPERAND (expr, 1))); 19978 19979 /* If the type is unknown, it can't really be non-dependent */ 19980 gcc_assert (TREE_TYPE (expr) != unknown_type_node); 19981 19982 /* Otherwise, build a NON_DEPENDENT_EXPR. */ 19983 return build1 (NON_DEPENDENT_EXPR, TREE_TYPE (expr), expr); 19984 } 19985 19986 /* ARGS is a vector of expressions as arguments to a function call. 19987 Replace the arguments with equivalent non-dependent expressions. 19988 This modifies ARGS in place. */ 19989 19990 void 19991 make_args_non_dependent (VEC(tree,gc) *args) 19992 { 19993 unsigned int ix; 19994 tree arg; 19995 19996 FOR_EACH_VEC_ELT (tree, args, ix, arg) 19997 { 19998 tree newarg = build_non_dependent_expr (arg); 19999 if (newarg != arg) 20000 VEC_replace (tree, args, ix, newarg); 20001 } 20002 } 20003 20004 /* Returns a type which represents 'auto'. We use a TEMPLATE_TYPE_PARM 20005 with a level one deeper than the actual template parms. */ 20006 20007 tree 20008 make_auto (void) 20009 { 20010 tree au = cxx_make_type (TEMPLATE_TYPE_PARM); 20011 TYPE_NAME (au) = build_decl (BUILTINS_LOCATION, 20012 TYPE_DECL, get_identifier ("auto"), au); 20013 TYPE_STUB_DECL (au) = TYPE_NAME (au); 20014 TEMPLATE_TYPE_PARM_INDEX (au) = build_template_parm_index 20015 (0, processing_template_decl + 1, processing_template_decl + 1, 20016 TYPE_NAME (au), NULL_TREE); 20017 TYPE_CANONICAL (au) = canonical_type_parameter (au); 20018 DECL_ARTIFICIAL (TYPE_NAME (au)) = 1; 20019 SET_DECL_TEMPLATE_PARM_P (TYPE_NAME (au)); 20020 20021 return au; 20022 } 20023 20024 /* Given type ARG, return std::initializer_list<ARG>. */ 20025 20026 static tree 20027 listify (tree arg) 20028 { 20029 tree std_init_list = namespace_binding 20030 (get_identifier ("initializer_list"), std_node); 20031 tree argvec; 20032 if (!std_init_list || !DECL_CLASS_TEMPLATE_P (std_init_list)) 20033 { 20034 error ("deducing from brace-enclosed initializer list requires " 20035 "#include <initializer_list>"); 20036 return error_mark_node; 20037 } 20038 argvec = make_tree_vec (1); 20039 TREE_VEC_ELT (argvec, 0) = arg; 20040 return lookup_template_class (std_init_list, argvec, NULL_TREE, 20041 NULL_TREE, 0, tf_warning_or_error); 20042 } 20043 20044 /* Replace auto in TYPE with std::initializer_list<auto>. */ 20045 20046 static tree 20047 listify_autos (tree type, tree auto_node) 20048 { 20049 tree init_auto = listify (auto_node); 20050 tree argvec = make_tree_vec (1); 20051 TREE_VEC_ELT (argvec, 0) = init_auto; 20052 if (processing_template_decl) 20053 argvec = add_to_template_args (current_template_args (), argvec); 20054 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE); 20055 } 20056 20057 /* walk_tree helper for do_auto_deduction. */ 20058 20059 static tree 20060 contains_auto_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED, 20061 void *type) 20062 { 20063 /* Is this a variable with the type we're looking for? */ 20064 if (DECL_P (*tp) 20065 && TREE_TYPE (*tp) == type) 20066 return *tp; 20067 else 20068 return NULL_TREE; 20069 } 20070 20071 /* Replace occurrences of 'auto' in TYPE with the appropriate type deduced 20072 from INIT. AUTO_NODE is the TEMPLATE_TYPE_PARM used for 'auto' in TYPE. */ 20073 20074 tree 20075 do_auto_deduction (tree type, tree init, tree auto_node) 20076 { 20077 tree parms, tparms, targs; 20078 tree args[1]; 20079 tree decl; 20080 int val; 20081 20082 if (type_dependent_expression_p (init)) 20083 /* Defining a subset of type-dependent expressions that we can deduce 20084 from ahead of time isn't worth the trouble. */ 20085 return type; 20086 20087 /* The name of the object being declared shall not appear in the 20088 initializer expression. */ 20089 decl = cp_walk_tree_without_duplicates (&init, contains_auto_r, type); 20090 if (decl) 20091 { 20092 error ("variable %q#D with %<auto%> type used in its own " 20093 "initializer", decl); 20094 return error_mark_node; 20095 } 20096 20097 /* [dcl.spec.auto]: Obtain P from T by replacing the occurrences of auto 20098 with either a new invented type template parameter U or, if the 20099 initializer is a braced-init-list (8.5.4), with 20100 std::initializer_list<U>. */ 20101 if (BRACE_ENCLOSED_INITIALIZER_P (init)) 20102 type = listify_autos (type, auto_node); 20103 20104 init = resolve_nondeduced_context (init); 20105 20106 parms = build_tree_list (NULL_TREE, type); 20107 args[0] = init; 20108 tparms = make_tree_vec (1); 20109 targs = make_tree_vec (1); 20110 TREE_VEC_ELT (tparms, 0) 20111 = build_tree_list (NULL_TREE, TYPE_NAME (auto_node)); 20112 val = type_unification_real (tparms, targs, parms, args, 1, 0, 20113 DEDUCE_CALL, LOOKUP_NORMAL, 20114 /*explain_p=*/false); 20115 if (val > 0) 20116 { 20117 if (processing_template_decl) 20118 /* Try again at instantiation time. */ 20119 return type; 20120 if (type && type != error_mark_node) 20121 /* If type is error_mark_node a diagnostic must have been 20122 emitted by now. Also, having a mention to '<type error>' 20123 in the diagnostic is not really useful to the user. */ 20124 error ("unable to deduce %qT from %qE", type, init); 20125 return error_mark_node; 20126 } 20127 20128 /* If the list of declarators contains more than one declarator, the type 20129 of each declared variable is determined as described above. If the 20130 type deduced for the template parameter U is not the same in each 20131 deduction, the program is ill-formed. */ 20132 if (TREE_TYPE (auto_node) 20133 && !same_type_p (TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0))) 20134 { 20135 error ("inconsistent deduction for %qT: %qT and then %qT", 20136 auto_node, TREE_TYPE (auto_node), TREE_VEC_ELT (targs, 0)); 20137 return error_mark_node; 20138 } 20139 TREE_TYPE (auto_node) = TREE_VEC_ELT (targs, 0); 20140 20141 if (processing_template_decl) 20142 targs = add_to_template_args (current_template_args (), targs); 20143 return tsubst (type, targs, tf_warning_or_error, NULL_TREE); 20144 } 20145 20146 /* Substitutes LATE_RETURN_TYPE for 'auto' in TYPE and returns the 20147 result. */ 20148 20149 tree 20150 splice_late_return_type (tree type, tree late_return_type) 20151 { 20152 tree argvec; 20153 20154 if (late_return_type == NULL_TREE) 20155 return type; 20156 argvec = make_tree_vec (1); 20157 TREE_VEC_ELT (argvec, 0) = late_return_type; 20158 if (processing_template_parmlist) 20159 /* For a late-specified return type in a template type-parameter, we 20160 need to add a dummy argument level for its parmlist. */ 20161 argvec = add_to_template_args 20162 (make_tree_vec (processing_template_parmlist), argvec); 20163 if (current_template_parms) 20164 argvec = add_to_template_args (current_template_args (), argvec); 20165 return tsubst (type, argvec, tf_warning_or_error, NULL_TREE); 20166 } 20167 20168 /* Returns true iff TYPE is a TEMPLATE_TYPE_PARM representing 'auto'. */ 20169 20170 bool 20171 is_auto (const_tree type) 20172 { 20173 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM 20174 && TYPE_IDENTIFIER (type) == get_identifier ("auto")) 20175 return true; 20176 else 20177 return false; 20178 } 20179 20180 /* Returns true iff TYPE contains a use of 'auto'. Since auto can only 20181 appear as a type-specifier for the declaration in question, we don't 20182 have to look through the whole type. */ 20183 20184 tree 20185 type_uses_auto (tree type) 20186 { 20187 enum tree_code code; 20188 if (is_auto (type)) 20189 return type; 20190 20191 code = TREE_CODE (type); 20192 20193 if (code == POINTER_TYPE || code == REFERENCE_TYPE 20194 || code == OFFSET_TYPE || code == FUNCTION_TYPE 20195 || code == METHOD_TYPE || code == ARRAY_TYPE) 20196 return type_uses_auto (TREE_TYPE (type)); 20197 20198 if (TYPE_PTRMEMFUNC_P (type)) 20199 return type_uses_auto (TREE_TYPE (TREE_TYPE 20200 (TYPE_PTRMEMFUNC_FN_TYPE (type)))); 20201 20202 return NULL_TREE; 20203 } 20204 20205 /* For a given template T, return the vector of typedefs referenced 20206 in T for which access check is needed at T instantiation time. 20207 T is either a FUNCTION_DECL or a RECORD_TYPE. 20208 Those typedefs were added to T by the function 20209 append_type_to_template_for_access_check. */ 20210 20211 VEC(qualified_typedef_usage_t,gc)* 20212 get_types_needing_access_check (tree t) 20213 { 20214 tree ti; 20215 VEC(qualified_typedef_usage_t,gc) *result = NULL; 20216 20217 if (!t || t == error_mark_node) 20218 return NULL; 20219 20220 if (!(ti = get_template_info (t))) 20221 return NULL; 20222 20223 if (CLASS_TYPE_P (t) 20224 || TREE_CODE (t) == FUNCTION_DECL) 20225 { 20226 if (!TI_TEMPLATE (ti)) 20227 return NULL; 20228 20229 result = TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti); 20230 } 20231 20232 return result; 20233 } 20234 20235 /* Append the typedef TYPE_DECL used in template T to a list of typedefs 20236 tied to T. That list of typedefs will be access checked at 20237 T instantiation time. 20238 T is either a FUNCTION_DECL or a RECORD_TYPE. 20239 TYPE_DECL is a TYPE_DECL node representing a typedef. 20240 SCOPE is the scope through which TYPE_DECL is accessed. 20241 LOCATION is the location of the usage point of TYPE_DECL. 20242 20243 This function is a subroutine of 20244 append_type_to_template_for_access_check. */ 20245 20246 static void 20247 append_type_to_template_for_access_check_1 (tree t, 20248 tree type_decl, 20249 tree scope, 20250 location_t location) 20251 { 20252 qualified_typedef_usage_t typedef_usage; 20253 tree ti; 20254 20255 if (!t || t == error_mark_node) 20256 return; 20257 20258 gcc_assert ((TREE_CODE (t) == FUNCTION_DECL 20259 || CLASS_TYPE_P (t)) 20260 && type_decl 20261 && TREE_CODE (type_decl) == TYPE_DECL 20262 && scope); 20263 20264 if (!(ti = get_template_info (t))) 20265 return; 20266 20267 gcc_assert (TI_TEMPLATE (ti)); 20268 20269 typedef_usage.typedef_decl = type_decl; 20270 typedef_usage.context = scope; 20271 typedef_usage.locus = location; 20272 20273 VEC_safe_push (qualified_typedef_usage_t, gc, 20274 TI_TYPEDEFS_NEEDING_ACCESS_CHECKING (ti), 20275 &typedef_usage); 20276 } 20277 20278 /* Append TYPE_DECL to the template TEMPL. 20279 TEMPL is either a class type, a FUNCTION_DECL or a a TEMPLATE_DECL. 20280 At TEMPL instanciation time, TYPE_DECL will be checked to see 20281 if it can be accessed through SCOPE. 20282 LOCATION is the location of the usage point of TYPE_DECL. 20283 20284 e.g. consider the following code snippet: 20285 20286 class C 20287 { 20288 typedef int myint; 20289 }; 20290 20291 template<class U> struct S 20292 { 20293 C::myint mi; // <-- usage point of the typedef C::myint 20294 }; 20295 20296 S<char> s; 20297 20298 At S<char> instantiation time, we need to check the access of C::myint 20299 In other words, we need to check the access of the myint typedef through 20300 the C scope. For that purpose, this function will add the myint typedef 20301 and the scope C through which its being accessed to a list of typedefs 20302 tied to the template S. That list will be walked at template instantiation 20303 time and access check performed on each typedefs it contains. 20304 Note that this particular code snippet should yield an error because 20305 myint is private to C. */ 20306 20307 void 20308 append_type_to_template_for_access_check (tree templ, 20309 tree type_decl, 20310 tree scope, 20311 location_t location) 20312 { 20313 qualified_typedef_usage_t *iter; 20314 int i; 20315 20316 gcc_assert (type_decl && (TREE_CODE (type_decl) == TYPE_DECL)); 20317 20318 /* Make sure we don't append the type to the template twice. */ 20319 FOR_EACH_VEC_ELT (qualified_typedef_usage_t, 20320 get_types_needing_access_check (templ), 20321 i, iter) 20322 if (iter->typedef_decl == type_decl && scope == iter->context) 20323 return; 20324 20325 append_type_to_template_for_access_check_1 (templ, type_decl, 20326 scope, location); 20327 } 20328 20329 /* Set up the hash tables for template instantiations. */ 20330 20331 void 20332 init_template_processing (void) 20333 { 20334 decl_specializations = htab_create_ggc (37, 20335 hash_specialization, 20336 eq_specializations, 20337 ggc_free); 20338 type_specializations = htab_create_ggc (37, 20339 hash_specialization, 20340 eq_specializations, 20341 ggc_free); 20342 } 20343 20344 /* Print stats about the template hash tables for -fstats. */ 20345 20346 void 20347 print_template_statistics (void) 20348 { 20349 fprintf (stderr, "decl_specializations: size %ld, %ld elements, " 20350 "%f collisions\n", (long) htab_size (decl_specializations), 20351 (long) htab_elements (decl_specializations), 20352 htab_collisions (decl_specializations)); 20353 fprintf (stderr, "type_specializations: size %ld, %ld elements, " 20354 "%f collisions\n", (long) htab_size (type_specializations), 20355 (long) htab_elements (type_specializations), 20356 htab_collisions (type_specializations)); 20357 } 20358 20359 #include "gt-cp-pt.h" 20360