1 /* Process declarations and variables for C++ compiler. 2 Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 4 2011 Free Software Foundation, Inc. 5 Hacked by Michael Tiemann (tiemann@cygnus.com) 6 7 This file is part of GCC. 8 9 GCC is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 3, or (at your option) 12 any later version. 13 14 GCC is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with GCC; see the file COPYING3. If not see 21 <http://www.gnu.org/licenses/>. */ 22 23 24 /* Process declarations and symbol lookup for C++ front end. 25 Also constructs types; the standard scalar types at initialization, 26 and structure, union, array and enum types when they are declared. */ 27 28 /* ??? not all decl nodes are given the most useful possible 29 line numbers. For example, the CONST_DECLs for enum values. */ 30 31 #include "config.h" 32 #include "system.h" 33 #include "coretypes.h" 34 #include "tm.h" 35 #include "tree.h" 36 #include "flags.h" 37 #include "cp-tree.h" 38 #include "decl.h" 39 #include "output.h" 40 #include "toplev.h" 41 #include "timevar.h" 42 #include "cpplib.h" 43 #include "target.h" 44 #include "c-family/c-common.h" 45 #include "c-family/c-objc.h" 46 #include "cgraph.h" 47 #include "tree-inline.h" 48 #include "c-family/c-pragma.h" 49 #include "tree-dump.h" 50 #include "intl.h" 51 #include "gimple.h" 52 #include "pointer-set.h" 53 #include "splay-tree.h" 54 #include "langhooks.h" 55 #include "c-family/c-ada-spec.h" 56 57 extern cpp_reader *parse_in; 58 59 /* This structure contains information about the initializations 60 and/or destructions required for a particular priority level. */ 61 typedef struct priority_info_s { 62 /* Nonzero if there have been any initializations at this priority 63 throughout the translation unit. */ 64 int initializations_p; 65 /* Nonzero if there have been any destructions at this priority 66 throughout the translation unit. */ 67 int destructions_p; 68 } *priority_info; 69 70 static void mark_vtable_entries (tree); 71 static bool maybe_emit_vtables (tree); 72 static bool acceptable_java_type (tree); 73 static tree start_objects (int, int); 74 static void finish_objects (int, int, tree); 75 static tree start_static_storage_duration_function (unsigned); 76 static void finish_static_storage_duration_function (tree); 77 static priority_info get_priority_info (int); 78 static void do_static_initialization_or_destruction (tree, bool); 79 static void one_static_initialization_or_destruction (tree, tree, bool); 80 static void generate_ctor_or_dtor_function (bool, int, location_t *); 81 static int generate_ctor_and_dtor_functions_for_priority (splay_tree_node, 82 void *); 83 static tree prune_vars_needing_no_initialization (tree *); 84 static void write_out_vars (tree); 85 static void import_export_class (tree); 86 static tree get_guard_bits (tree); 87 static void determine_visibility_from_class (tree, tree); 88 static bool determine_hidden_inline (tree); 89 static bool decl_defined_p (tree); 90 91 /* A list of static class variables. This is needed, because a 92 static class variable can be declared inside the class without 93 an initializer, and then initialized, statically, outside the class. */ 94 static GTY(()) VEC(tree,gc) *pending_statics; 95 96 /* A list of functions which were declared inline, but which we 97 may need to emit outline anyway. */ 98 static GTY(()) VEC(tree,gc) *deferred_fns; 99 100 /* A list of decls that use types with no linkage, which we need to make 101 sure are defined. */ 102 static GTY(()) VEC(tree,gc) *no_linkage_decls; 103 104 /* Nonzero if we're done parsing and into end-of-file activities. */ 105 106 int at_eof; 107 108 109 110 /* Return a member function type (a METHOD_TYPE), given FNTYPE (a 111 FUNCTION_TYPE), CTYPE (class type), and QUALS (the cv-qualifiers 112 that apply to the function). */ 113 114 tree 115 build_memfn_type (tree fntype, tree ctype, cp_cv_quals quals) 116 { 117 tree raises; 118 tree attrs; 119 int type_quals; 120 121 if (fntype == error_mark_node || ctype == error_mark_node) 122 return error_mark_node; 123 124 gcc_assert (TREE_CODE (fntype) == FUNCTION_TYPE 125 || TREE_CODE (fntype) == METHOD_TYPE); 126 127 type_quals = quals & ~TYPE_QUAL_RESTRICT; 128 ctype = cp_build_qualified_type (ctype, type_quals); 129 raises = TYPE_RAISES_EXCEPTIONS (fntype); 130 attrs = TYPE_ATTRIBUTES (fntype); 131 fntype = build_method_type_directly (ctype, TREE_TYPE (fntype), 132 (TREE_CODE (fntype) == METHOD_TYPE 133 ? TREE_CHAIN (TYPE_ARG_TYPES (fntype)) 134 : TYPE_ARG_TYPES (fntype))); 135 if (raises) 136 fntype = build_exception_variant (fntype, raises); 137 if (attrs) 138 fntype = cp_build_type_attribute_variant (fntype, attrs); 139 140 return fntype; 141 } 142 143 /* Return a variant of FNTYPE, a FUNCTION_TYPE or METHOD_TYPE, with its 144 return type changed to NEW_RET. */ 145 146 tree 147 change_return_type (tree new_ret, tree fntype) 148 { 149 tree newtype; 150 tree args = TYPE_ARG_TYPES (fntype); 151 tree raises = TYPE_RAISES_EXCEPTIONS (fntype); 152 tree attrs = TYPE_ATTRIBUTES (fntype); 153 154 if (same_type_p (new_ret, TREE_TYPE (fntype))) 155 return fntype; 156 157 if (TREE_CODE (fntype) == FUNCTION_TYPE) 158 { 159 newtype = build_function_type (new_ret, args); 160 newtype = apply_memfn_quals (newtype, type_memfn_quals (fntype)); 161 } 162 else 163 newtype = build_method_type_directly 164 (class_of_this_parm (fntype), new_ret, TREE_CHAIN (args)); 165 if (raises) 166 newtype = build_exception_variant (newtype, raises); 167 if (attrs) 168 newtype = cp_build_type_attribute_variant (newtype, attrs); 169 170 return newtype; 171 } 172 173 /* Build a PARM_DECL with NAME and TYPE, and set DECL_ARG_TYPE 174 appropriately. */ 175 176 tree 177 cp_build_parm_decl (tree name, tree type) 178 { 179 tree parm = build_decl (input_location, 180 PARM_DECL, name, type); 181 /* DECL_ARG_TYPE is only used by the back end and the back end never 182 sees templates. */ 183 if (!processing_template_decl) 184 DECL_ARG_TYPE (parm) = type_passed_as (type); 185 186 /* If the type is a pack expansion, then we have a function 187 parameter pack. */ 188 if (type && TREE_CODE (type) == TYPE_PACK_EXPANSION) 189 FUNCTION_PARAMETER_PACK_P (parm) = 1; 190 191 return parm; 192 } 193 194 /* Returns a PARM_DECL for a parameter of the indicated TYPE, with the 195 indicated NAME. */ 196 197 tree 198 build_artificial_parm (tree name, tree type) 199 { 200 tree parm = cp_build_parm_decl (name, type); 201 DECL_ARTIFICIAL (parm) = 1; 202 /* All our artificial parms are implicitly `const'; they cannot be 203 assigned to. */ 204 TREE_READONLY (parm) = 1; 205 return parm; 206 } 207 208 /* Constructors for types with virtual baseclasses need an "in-charge" flag 209 saying whether this constructor is responsible for initialization of 210 virtual baseclasses or not. All destructors also need this "in-charge" 211 flag, which additionally determines whether or not the destructor should 212 free the memory for the object. 213 214 This function adds the "in-charge" flag to member function FN if 215 appropriate. It is called from grokclassfn and tsubst. 216 FN must be either a constructor or destructor. 217 218 The in-charge flag follows the 'this' parameter, and is followed by the 219 VTT parm (if any), then the user-written parms. */ 220 221 void 222 maybe_retrofit_in_chrg (tree fn) 223 { 224 tree basetype, arg_types, parms, parm, fntype; 225 226 /* If we've already add the in-charge parameter don't do it again. */ 227 if (DECL_HAS_IN_CHARGE_PARM_P (fn)) 228 return; 229 230 /* When processing templates we can't know, in general, whether or 231 not we're going to have virtual baseclasses. */ 232 if (processing_template_decl) 233 return; 234 235 /* We don't need an in-charge parameter for constructors that don't 236 have virtual bases. */ 237 if (DECL_CONSTRUCTOR_P (fn) 238 && !CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn))) 239 return; 240 241 arg_types = TYPE_ARG_TYPES (TREE_TYPE (fn)); 242 basetype = TREE_TYPE (TREE_VALUE (arg_types)); 243 arg_types = TREE_CHAIN (arg_types); 244 245 parms = DECL_CHAIN (DECL_ARGUMENTS (fn)); 246 247 /* If this is a subobject constructor or destructor, our caller will 248 pass us a pointer to our VTT. */ 249 if (CLASSTYPE_VBASECLASSES (DECL_CONTEXT (fn))) 250 { 251 parm = build_artificial_parm (vtt_parm_identifier, vtt_parm_type); 252 253 /* First add it to DECL_ARGUMENTS between 'this' and the real args... */ 254 DECL_CHAIN (parm) = parms; 255 parms = parm; 256 257 /* ...and then to TYPE_ARG_TYPES. */ 258 arg_types = hash_tree_chain (vtt_parm_type, arg_types); 259 260 DECL_HAS_VTT_PARM_P (fn) = 1; 261 } 262 263 /* Then add the in-charge parm (before the VTT parm). */ 264 parm = build_artificial_parm (in_charge_identifier, integer_type_node); 265 DECL_CHAIN (parm) = parms; 266 parms = parm; 267 arg_types = hash_tree_chain (integer_type_node, arg_types); 268 269 /* Insert our new parameter(s) into the list. */ 270 DECL_CHAIN (DECL_ARGUMENTS (fn)) = parms; 271 272 /* And rebuild the function type. */ 273 fntype = build_method_type_directly (basetype, TREE_TYPE (TREE_TYPE (fn)), 274 arg_types); 275 if (TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn))) 276 fntype = build_exception_variant (fntype, 277 TYPE_RAISES_EXCEPTIONS (TREE_TYPE (fn))); 278 if (TYPE_ATTRIBUTES (TREE_TYPE (fn))) 279 fntype = (cp_build_type_attribute_variant 280 (fntype, TYPE_ATTRIBUTES (TREE_TYPE (fn)))); 281 TREE_TYPE (fn) = fntype; 282 283 /* Now we've got the in-charge parameter. */ 284 DECL_HAS_IN_CHARGE_PARM_P (fn) = 1; 285 } 286 287 /* Classes overload their constituent function names automatically. 288 When a function name is declared in a record structure, 289 its name is changed to it overloaded name. Since names for 290 constructors and destructors can conflict, we place a leading 291 '$' for destructors. 292 293 CNAME is the name of the class we are grokking for. 294 295 FUNCTION is a FUNCTION_DECL. It was created by `grokdeclarator'. 296 297 FLAGS contains bits saying what's special about today's 298 arguments. DTOR_FLAG == DESTRUCTOR. 299 300 If FUNCTION is a destructor, then we must add the `auto-delete' field 301 as a second parameter. There is some hair associated with the fact 302 that we must "declare" this variable in the manner consistent with the 303 way the rest of the arguments were declared. 304 305 QUALS are the qualifiers for the this pointer. */ 306 307 void 308 grokclassfn (tree ctype, tree function, enum overload_flags flags) 309 { 310 tree fn_name = DECL_NAME (function); 311 312 /* Even within an `extern "C"' block, members get C++ linkage. See 313 [dcl.link] for details. */ 314 SET_DECL_LANGUAGE (function, lang_cplusplus); 315 316 if (fn_name == NULL_TREE) 317 { 318 error ("name missing for member function"); 319 fn_name = get_identifier ("<anonymous>"); 320 DECL_NAME (function) = fn_name; 321 } 322 323 DECL_CONTEXT (function) = ctype; 324 325 if (flags == DTOR_FLAG) 326 DECL_DESTRUCTOR_P (function) = 1; 327 328 if (flags == DTOR_FLAG || DECL_CONSTRUCTOR_P (function)) 329 maybe_retrofit_in_chrg (function); 330 } 331 332 /* Create an ARRAY_REF, checking for the user doing things backwards 333 along the way. */ 334 335 tree 336 grok_array_decl (tree array_expr, tree index_exp) 337 { 338 tree type; 339 tree expr; 340 tree orig_array_expr = array_expr; 341 tree orig_index_exp = index_exp; 342 343 if (error_operand_p (array_expr) || error_operand_p (index_exp)) 344 return error_mark_node; 345 346 if (processing_template_decl) 347 { 348 if (type_dependent_expression_p (array_expr) 349 || type_dependent_expression_p (index_exp)) 350 return build_min_nt (ARRAY_REF, array_expr, index_exp, 351 NULL_TREE, NULL_TREE); 352 array_expr = build_non_dependent_expr (array_expr); 353 index_exp = build_non_dependent_expr (index_exp); 354 } 355 356 type = TREE_TYPE (array_expr); 357 gcc_assert (type); 358 type = non_reference (type); 359 360 /* If they have an `operator[]', use that. */ 361 if (MAYBE_CLASS_TYPE_P (type) || MAYBE_CLASS_TYPE_P (TREE_TYPE (index_exp))) 362 expr = build_new_op (ARRAY_REF, LOOKUP_NORMAL, 363 array_expr, index_exp, NULL_TREE, 364 /*overload=*/NULL, tf_warning_or_error); 365 else 366 { 367 tree p1, p2, i1, i2; 368 369 /* Otherwise, create an ARRAY_REF for a pointer or array type. 370 It is a little-known fact that, if `a' is an array and `i' is 371 an int, you can write `i[a]', which means the same thing as 372 `a[i]'. */ 373 if (TREE_CODE (type) == ARRAY_TYPE) 374 p1 = array_expr; 375 else 376 p1 = build_expr_type_conversion (WANT_POINTER, array_expr, false); 377 378 if (TREE_CODE (TREE_TYPE (index_exp)) == ARRAY_TYPE) 379 p2 = index_exp; 380 else 381 p2 = build_expr_type_conversion (WANT_POINTER, index_exp, false); 382 383 i1 = build_expr_type_conversion (WANT_INT | WANT_ENUM, array_expr, 384 false); 385 i2 = build_expr_type_conversion (WANT_INT | WANT_ENUM, index_exp, 386 false); 387 388 if ((p1 && i2) && (i1 && p2)) 389 error ("ambiguous conversion for array subscript"); 390 391 if (p1 && i2) 392 array_expr = p1, index_exp = i2; 393 else if (i1 && p2) 394 array_expr = p2, index_exp = i1; 395 else 396 { 397 error ("invalid types %<%T[%T]%> for array subscript", 398 type, TREE_TYPE (index_exp)); 399 return error_mark_node; 400 } 401 402 if (array_expr == error_mark_node || index_exp == error_mark_node) 403 error ("ambiguous conversion for array subscript"); 404 405 expr = build_array_ref (input_location, array_expr, index_exp); 406 } 407 if (processing_template_decl && expr != error_mark_node) 408 return build_min_non_dep (ARRAY_REF, expr, orig_array_expr, orig_index_exp, 409 NULL_TREE, NULL_TREE); 410 return expr; 411 } 412 413 /* Given the cast expression EXP, checking out its validity. Either return 414 an error_mark_node if there was an unavoidable error, return a cast to 415 void for trying to delete a pointer w/ the value 0, or return the 416 call to delete. If DOING_VEC is true, we handle things differently 417 for doing an array delete. 418 Implements ARM $5.3.4. This is called from the parser. */ 419 420 tree 421 delete_sanity (tree exp, tree size, bool doing_vec, int use_global_delete, 422 tsubst_flags_t complain) 423 { 424 tree t, type; 425 426 if (exp == error_mark_node) 427 return exp; 428 429 if (processing_template_decl) 430 { 431 t = build_min (DELETE_EXPR, void_type_node, exp, size); 432 DELETE_EXPR_USE_GLOBAL (t) = use_global_delete; 433 DELETE_EXPR_USE_VEC (t) = doing_vec; 434 TREE_SIDE_EFFECTS (t) = 1; 435 return t; 436 } 437 438 /* An array can't have been allocated by new, so complain. */ 439 if (TREE_CODE (exp) == VAR_DECL 440 && TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE) 441 warning (0, "deleting array %q#D", exp); 442 443 t = build_expr_type_conversion (WANT_POINTER, exp, true); 444 445 if (t == NULL_TREE || t == error_mark_node) 446 { 447 error ("type %q#T argument given to %<delete%>, expected pointer", 448 TREE_TYPE (exp)); 449 return error_mark_node; 450 } 451 452 type = TREE_TYPE (t); 453 454 /* As of Valley Forge, you can delete a pointer to const. */ 455 456 /* You can't delete functions. */ 457 if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE) 458 { 459 error ("cannot delete a function. Only pointer-to-objects are " 460 "valid arguments to %<delete%>"); 461 return error_mark_node; 462 } 463 464 /* Deleting ptr to void is undefined behavior [expr.delete/3]. */ 465 if (TREE_CODE (TREE_TYPE (type)) == VOID_TYPE) 466 { 467 warning (0, "deleting %qT is undefined", type); 468 doing_vec = 0; 469 } 470 471 /* Deleting a pointer with the value zero is valid and has no effect. */ 472 if (integer_zerop (t)) 473 return build1 (NOP_EXPR, void_type_node, t); 474 475 if (doing_vec) 476 return build_vec_delete (t, /*maxindex=*/NULL_TREE, 477 sfk_deleting_destructor, 478 use_global_delete, complain); 479 else 480 return build_delete (type, t, sfk_deleting_destructor, 481 LOOKUP_NORMAL, use_global_delete, 482 complain); 483 } 484 485 /* Report an error if the indicated template declaration is not the 486 sort of thing that should be a member template. */ 487 488 void 489 check_member_template (tree tmpl) 490 { 491 tree decl; 492 493 gcc_assert (TREE_CODE (tmpl) == TEMPLATE_DECL); 494 decl = DECL_TEMPLATE_RESULT (tmpl); 495 496 if (TREE_CODE (decl) == FUNCTION_DECL 497 || DECL_ALIAS_TEMPLATE_P (tmpl) 498 || (TREE_CODE (decl) == TYPE_DECL 499 && MAYBE_CLASS_TYPE_P (TREE_TYPE (decl)))) 500 { 501 /* The parser rejects template declarations in local classes. */ 502 gcc_assert (!current_function_decl); 503 /* The parser rejects any use of virtual in a function template. */ 504 gcc_assert (!(TREE_CODE (decl) == FUNCTION_DECL 505 && DECL_VIRTUAL_P (decl))); 506 507 /* The debug-information generating code doesn't know what to do 508 with member templates. */ 509 DECL_IGNORED_P (tmpl) = 1; 510 } 511 else 512 error ("template declaration of %q#D", decl); 513 } 514 515 /* Return true iff TYPE is a valid Java parameter or return type. */ 516 517 static bool 518 acceptable_java_type (tree type) 519 { 520 if (type == error_mark_node) 521 return false; 522 523 if (TREE_CODE (type) == VOID_TYPE || TYPE_FOR_JAVA (type)) 524 return true; 525 if (TREE_CODE (type) == POINTER_TYPE || TREE_CODE (type) == REFERENCE_TYPE) 526 { 527 type = TREE_TYPE (type); 528 if (TREE_CODE (type) == RECORD_TYPE) 529 { 530 tree args; int i; 531 if (! TYPE_FOR_JAVA (type)) 532 return false; 533 if (! CLASSTYPE_TEMPLATE_INFO (type)) 534 return true; 535 args = CLASSTYPE_TI_ARGS (type); 536 i = TREE_VEC_LENGTH (args); 537 while (--i >= 0) 538 { 539 type = TREE_VEC_ELT (args, i); 540 if (TREE_CODE (type) == POINTER_TYPE) 541 type = TREE_TYPE (type); 542 if (! TYPE_FOR_JAVA (type)) 543 return false; 544 } 545 return true; 546 } 547 } 548 return false; 549 } 550 551 /* For a METHOD in a Java class CTYPE, return true if 552 the parameter and return types are valid Java types. 553 Otherwise, print appropriate error messages, and return false. */ 554 555 bool 556 check_java_method (tree method) 557 { 558 bool jerr = false; 559 tree arg_types = TYPE_ARG_TYPES (TREE_TYPE (method)); 560 tree ret_type = TREE_TYPE (TREE_TYPE (method)); 561 562 if (!acceptable_java_type (ret_type)) 563 { 564 error ("Java method %qD has non-Java return type %qT", 565 method, ret_type); 566 jerr = true; 567 } 568 569 arg_types = TREE_CHAIN (arg_types); 570 if (DECL_HAS_IN_CHARGE_PARM_P (method)) 571 arg_types = TREE_CHAIN (arg_types); 572 if (DECL_HAS_VTT_PARM_P (method)) 573 arg_types = TREE_CHAIN (arg_types); 574 575 for (; arg_types != NULL_TREE; arg_types = TREE_CHAIN (arg_types)) 576 { 577 tree type = TREE_VALUE (arg_types); 578 if (!acceptable_java_type (type)) 579 { 580 if (type != error_mark_node) 581 error ("Java method %qD has non-Java parameter type %qT", 582 method, type); 583 jerr = true; 584 } 585 } 586 return !jerr; 587 } 588 589 /* Sanity check: report error if this function FUNCTION is not 590 really a member of the class (CTYPE) it is supposed to belong to. 591 TEMPLATE_PARMS is used to specify the template parameters of a member 592 template passed as FUNCTION_DECL. If the member template is passed as a 593 TEMPLATE_DECL, it can be NULL since the parameters can be extracted 594 from the declaration. If the function is not a function template, it 595 must be NULL. 596 It returns the original declaration for the function, NULL_TREE if 597 no declaration was found, error_mark_node if an error was emitted. */ 598 599 tree 600 check_classfn (tree ctype, tree function, tree template_parms) 601 { 602 int ix; 603 bool is_template; 604 tree pushed_scope; 605 606 if (DECL_USE_TEMPLATE (function) 607 && !(TREE_CODE (function) == TEMPLATE_DECL 608 && DECL_TEMPLATE_SPECIALIZATION (function)) 609 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (function))) 610 /* Since this is a specialization of a member template, 611 we're not going to find the declaration in the class. 612 For example, in: 613 614 struct S { template <typename T> void f(T); }; 615 template <> void S::f(int); 616 617 we're not going to find `S::f(int)', but there's no 618 reason we should, either. We let our callers know we didn't 619 find the method, but we don't complain. */ 620 return NULL_TREE; 621 622 /* Basic sanity check: for a template function, the template parameters 623 either were not passed, or they are the same of DECL_TEMPLATE_PARMS. */ 624 if (TREE_CODE (function) == TEMPLATE_DECL) 625 { 626 if (template_parms 627 && !comp_template_parms (template_parms, 628 DECL_TEMPLATE_PARMS (function))) 629 { 630 error ("template parameter lists provided don%'t match the " 631 "template parameters of %qD", function); 632 return error_mark_node; 633 } 634 template_parms = DECL_TEMPLATE_PARMS (function); 635 } 636 637 /* OK, is this a definition of a member template? */ 638 is_template = (template_parms != NULL_TREE); 639 640 /* We must enter the scope here, because conversion operators are 641 named by target type, and type equivalence relies on typenames 642 resolving within the scope of CTYPE. */ 643 pushed_scope = push_scope (ctype); 644 ix = class_method_index_for_fn (complete_type (ctype), function); 645 if (ix >= 0) 646 { 647 VEC(tree,gc) *methods = CLASSTYPE_METHOD_VEC (ctype); 648 tree fndecls, fndecl = 0; 649 bool is_conv_op; 650 const char *format = NULL; 651 652 for (fndecls = VEC_index (tree, methods, ix); 653 fndecls; fndecls = OVL_NEXT (fndecls)) 654 { 655 tree p1, p2; 656 657 fndecl = OVL_CURRENT (fndecls); 658 p1 = TYPE_ARG_TYPES (TREE_TYPE (function)); 659 p2 = TYPE_ARG_TYPES (TREE_TYPE (fndecl)); 660 661 /* We cannot simply call decls_match because this doesn't 662 work for static member functions that are pretending to 663 be methods, and because the name may have been changed by 664 asm("new_name"). */ 665 666 /* Get rid of the this parameter on functions that become 667 static. */ 668 if (DECL_STATIC_FUNCTION_P (fndecl) 669 && TREE_CODE (TREE_TYPE (function)) == METHOD_TYPE) 670 p1 = TREE_CHAIN (p1); 671 672 /* A member template definition only matches a member template 673 declaration. */ 674 if (is_template != (TREE_CODE (fndecl) == TEMPLATE_DECL)) 675 continue; 676 677 if (same_type_p (TREE_TYPE (TREE_TYPE (function)), 678 TREE_TYPE (TREE_TYPE (fndecl))) 679 && compparms (p1, p2) 680 && (!is_template 681 || comp_template_parms (template_parms, 682 DECL_TEMPLATE_PARMS (fndecl))) 683 && (DECL_TEMPLATE_SPECIALIZATION (function) 684 == DECL_TEMPLATE_SPECIALIZATION (fndecl)) 685 && (!DECL_TEMPLATE_SPECIALIZATION (function) 686 || (DECL_TI_TEMPLATE (function) 687 == DECL_TI_TEMPLATE (fndecl)))) 688 break; 689 } 690 if (fndecls) 691 { 692 if (pushed_scope) 693 pop_scope (pushed_scope); 694 return OVL_CURRENT (fndecls); 695 } 696 697 error_at (DECL_SOURCE_LOCATION (function), 698 "prototype for %q#D does not match any in class %qT", 699 function, ctype); 700 is_conv_op = DECL_CONV_FN_P (fndecl); 701 702 if (is_conv_op) 703 ix = CLASSTYPE_FIRST_CONVERSION_SLOT; 704 fndecls = VEC_index (tree, methods, ix); 705 while (fndecls) 706 { 707 fndecl = OVL_CURRENT (fndecls); 708 fndecls = OVL_NEXT (fndecls); 709 710 if (!fndecls && is_conv_op) 711 { 712 if (VEC_length (tree, methods) > (size_t) ++ix) 713 { 714 fndecls = VEC_index (tree, methods, ix); 715 if (!DECL_CONV_FN_P (OVL_CURRENT (fndecls))) 716 { 717 fndecls = NULL_TREE; 718 is_conv_op = false; 719 } 720 } 721 else 722 is_conv_op = false; 723 } 724 if (format) 725 format = " %+#D"; 726 else if (fndecls) 727 format = N_("candidates are: %+#D"); 728 else 729 format = N_("candidate is: %+#D"); 730 error (format, fndecl); 731 } 732 } 733 else if (!COMPLETE_TYPE_P (ctype)) 734 cxx_incomplete_type_error (function, ctype); 735 else 736 error ("no %q#D member function declared in class %qT", 737 function, ctype); 738 739 if (pushed_scope) 740 pop_scope (pushed_scope); 741 return error_mark_node; 742 } 743 744 /* DECL is a function with vague linkage. Remember it so that at the 745 end of the translation unit we can decide whether or not to emit 746 it. */ 747 748 void 749 note_vague_linkage_fn (tree decl) 750 { 751 DECL_DEFER_OUTPUT (decl) = 1; 752 VEC_safe_push (tree, gc, deferred_fns, decl); 753 } 754 755 /* We have just processed the DECL, which is a static data member. 756 The other parameters are as for cp_finish_decl. */ 757 758 void 759 finish_static_data_member_decl (tree decl, 760 tree init, bool init_const_expr_p, 761 tree asmspec_tree, 762 int flags) 763 { 764 DECL_CONTEXT (decl) = current_class_type; 765 766 /* We cannot call pushdecl here, because that would fill in the 767 TREE_CHAIN of our decl. Instead, we modify cp_finish_decl to do 768 the right thing, namely, to put this decl out straight away. */ 769 770 if (! processing_template_decl) 771 VEC_safe_push (tree, gc, pending_statics, decl); 772 773 if (LOCAL_CLASS_P (current_class_type)) 774 permerror (input_location, "local class %q#T shall not have static data member %q#D", 775 current_class_type, decl); 776 777 DECL_IN_AGGR_P (decl) = 1; 778 779 if (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE 780 && TYPE_DOMAIN (TREE_TYPE (decl)) == NULL_TREE) 781 SET_VAR_HAD_UNKNOWN_BOUND (decl); 782 783 cp_finish_decl (decl, init, init_const_expr_p, asmspec_tree, flags); 784 } 785 786 /* DECLARATOR and DECLSPECS correspond to a class member. The other 787 parameters are as for cp_finish_decl. Return the DECL for the 788 class member declared. */ 789 790 tree 791 grokfield (const cp_declarator *declarator, 792 cp_decl_specifier_seq *declspecs, 793 tree init, bool init_const_expr_p, 794 tree asmspec_tree, 795 tree attrlist) 796 { 797 tree value; 798 const char *asmspec = 0; 799 int flags; 800 tree name; 801 802 if (init 803 && TREE_CODE (init) == TREE_LIST 804 && TREE_VALUE (init) == error_mark_node 805 && TREE_CHAIN (init) == NULL_TREE) 806 init = NULL_TREE; 807 808 value = grokdeclarator (declarator, declspecs, FIELD, init != 0, &attrlist); 809 if (! value || error_operand_p (value)) 810 /* friend or constructor went bad. */ 811 return error_mark_node; 812 813 if (TREE_CODE (value) == TYPE_DECL && init) 814 { 815 error ("typedef %qD is initialized (use decltype instead)", value); 816 init = NULL_TREE; 817 } 818 819 /* Pass friendly classes back. */ 820 if (value == void_type_node) 821 return value; 822 823 /* Pass friend decls back. */ 824 if ((TREE_CODE (value) == FUNCTION_DECL 825 || TREE_CODE (value) == TEMPLATE_DECL) 826 && DECL_CONTEXT (value) != current_class_type) 827 return value; 828 829 name = DECL_NAME (value); 830 831 if (name != NULL_TREE) 832 { 833 if (TREE_CODE (name) == TEMPLATE_ID_EXPR) 834 { 835 error ("explicit template argument list not allowed"); 836 return error_mark_node; 837 } 838 839 if (IDENTIFIER_POINTER (name)[0] == '_' 840 && ! strcmp (IDENTIFIER_POINTER (name), "_vptr")) 841 error ("member %qD conflicts with virtual function table field name", 842 value); 843 } 844 845 /* Stash away type declarations. */ 846 if (TREE_CODE (value) == TYPE_DECL) 847 { 848 DECL_NONLOCAL (value) = 1; 849 DECL_CONTEXT (value) = current_class_type; 850 851 if (attrlist) 852 { 853 int attrflags = 0; 854 855 /* If this is a typedef that names the class for linkage purposes 856 (7.1.3p8), apply any attributes directly to the type. */ 857 if (TAGGED_TYPE_P (TREE_TYPE (value)) 858 && value == TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (value)))) 859 attrflags = ATTR_FLAG_TYPE_IN_PLACE; 860 861 cplus_decl_attributes (&value, attrlist, attrflags); 862 } 863 864 if (declspecs->specs[(int)ds_typedef] 865 && TREE_TYPE (value) != error_mark_node 866 && TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (value))) != value) 867 set_underlying_type (value); 868 869 /* It's important that push_template_decl below follows 870 set_underlying_type above so that the created template 871 carries the properly set type of VALUE. */ 872 if (processing_template_decl) 873 value = push_template_decl (value); 874 875 record_locally_defined_typedef (value); 876 return value; 877 } 878 879 if (DECL_IN_AGGR_P (value)) 880 { 881 error ("%qD is already defined in %qT", value, DECL_CONTEXT (value)); 882 return void_type_node; 883 } 884 885 if (asmspec_tree && asmspec_tree != error_mark_node) 886 asmspec = TREE_STRING_POINTER (asmspec_tree); 887 888 if (init) 889 { 890 if (TREE_CODE (value) == FUNCTION_DECL) 891 { 892 /* Initializers for functions are rejected early in the parser. 893 If we get here, it must be a pure specifier for a method. */ 894 if (init == ridpointers[(int)RID_DELETE]) 895 { 896 DECL_DELETED_FN (value) = 1; 897 DECL_DECLARED_INLINE_P (value) = 1; 898 DECL_INITIAL (value) = error_mark_node; 899 } 900 else if (init == ridpointers[(int)RID_DEFAULT]) 901 { 902 if (defaultable_fn_check (value)) 903 { 904 DECL_DEFAULTED_FN (value) = 1; 905 DECL_INITIALIZED_IN_CLASS_P (value) = 1; 906 DECL_DECLARED_INLINE_P (value) = 1; 907 } 908 } 909 else if (TREE_CODE (init) == DEFAULT_ARG) 910 error ("invalid initializer for member function %qD", value); 911 else if (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE) 912 { 913 if (integer_zerop (init)) 914 DECL_PURE_VIRTUAL_P (value) = 1; 915 else if (error_operand_p (init)) 916 ; /* An error has already been reported. */ 917 else 918 error ("invalid initializer for member function %qD", 919 value); 920 } 921 else 922 { 923 gcc_assert (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE); 924 error ("initializer specified for static member function %qD", 925 value); 926 } 927 } 928 else if (TREE_CODE (value) == FIELD_DECL) 929 /* C++11 NSDMI, keep going. */; 930 else if (TREE_CODE (value) != VAR_DECL) 931 gcc_unreachable (); 932 else if (!processing_template_decl) 933 { 934 if (TREE_CODE (init) == CONSTRUCTOR) 935 init = digest_init (TREE_TYPE (value), init, tf_warning_or_error); 936 init = maybe_constant_init (init); 937 938 if (init != error_mark_node && !TREE_CONSTANT (init)) 939 { 940 /* We can allow references to things that are effectively 941 static, since references are initialized with the 942 address. */ 943 if (TREE_CODE (TREE_TYPE (value)) != REFERENCE_TYPE 944 || (TREE_STATIC (init) == 0 945 && (!DECL_P (init) || DECL_EXTERNAL (init) == 0))) 946 { 947 error ("field initializer is not constant"); 948 init = error_mark_node; 949 } 950 } 951 } 952 } 953 954 if (processing_template_decl 955 && (TREE_CODE (value) == VAR_DECL || TREE_CODE (value) == FUNCTION_DECL)) 956 { 957 value = push_template_decl (value); 958 if (error_operand_p (value)) 959 return error_mark_node; 960 } 961 962 if (attrlist) 963 cplus_decl_attributes (&value, attrlist, 0); 964 965 if (init && BRACE_ENCLOSED_INITIALIZER_P (init) 966 && CONSTRUCTOR_IS_DIRECT_INIT (init)) 967 flags = LOOKUP_NORMAL; 968 else 969 flags = LOOKUP_IMPLICIT; 970 971 switch (TREE_CODE (value)) 972 { 973 case VAR_DECL: 974 finish_static_data_member_decl (value, init, init_const_expr_p, 975 asmspec_tree, flags); 976 return value; 977 978 case FIELD_DECL: 979 if (asmspec) 980 error ("%<asm%> specifiers are not permitted on non-static data members"); 981 if (DECL_INITIAL (value) == error_mark_node) 982 init = error_mark_node; 983 cp_finish_decl (value, init, /*init_const_expr_p=*/false, 984 NULL_TREE, flags); 985 DECL_IN_AGGR_P (value) = 1; 986 return value; 987 988 case FUNCTION_DECL: 989 if (asmspec) 990 set_user_assembler_name (value, asmspec); 991 992 cp_finish_decl (value, 993 /*init=*/NULL_TREE, 994 /*init_const_expr_p=*/false, 995 asmspec_tree, flags); 996 997 /* Pass friends back this way. */ 998 if (DECL_FRIEND_P (value)) 999 return void_type_node; 1000 1001 DECL_IN_AGGR_P (value) = 1; 1002 return value; 1003 1004 default: 1005 gcc_unreachable (); 1006 } 1007 return NULL_TREE; 1008 } 1009 1010 /* Like `grokfield', but for bitfields. 1011 WIDTH is non-NULL for bit fields only, and is an INTEGER_CST node. */ 1012 1013 tree 1014 grokbitfield (const cp_declarator *declarator, 1015 cp_decl_specifier_seq *declspecs, tree width, 1016 tree attrlist) 1017 { 1018 tree value = grokdeclarator (declarator, declspecs, BITFIELD, 0, &attrlist); 1019 1020 if (value == error_mark_node) 1021 return NULL_TREE; /* friends went bad. */ 1022 1023 /* Pass friendly classes back. */ 1024 if (TREE_CODE (value) == VOID_TYPE) 1025 return void_type_node; 1026 1027 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (value)) 1028 && (POINTER_TYPE_P (value) 1029 || !dependent_type_p (TREE_TYPE (value)))) 1030 { 1031 error ("bit-field %qD with non-integral type", value); 1032 return error_mark_node; 1033 } 1034 1035 if (TREE_CODE (value) == TYPE_DECL) 1036 { 1037 error ("cannot declare %qD to be a bit-field type", value); 1038 return NULL_TREE; 1039 } 1040 1041 /* Usually, finish_struct_1 catches bitfields with invalid types. 1042 But, in the case of bitfields with function type, we confuse 1043 ourselves into thinking they are member functions, so we must 1044 check here. */ 1045 if (TREE_CODE (value) == FUNCTION_DECL) 1046 { 1047 error ("cannot declare bit-field %qD with function type", 1048 DECL_NAME (value)); 1049 return NULL_TREE; 1050 } 1051 1052 if (DECL_IN_AGGR_P (value)) 1053 { 1054 error ("%qD is already defined in the class %qT", value, 1055 DECL_CONTEXT (value)); 1056 return void_type_node; 1057 } 1058 1059 if (TREE_STATIC (value)) 1060 { 1061 error ("static member %qD cannot be a bit-field", value); 1062 return NULL_TREE; 1063 } 1064 cp_finish_decl (value, NULL_TREE, false, NULL_TREE, 0); 1065 1066 if (width != error_mark_node) 1067 { 1068 /* The width must be an integer type. */ 1069 if (!type_dependent_expression_p (width) 1070 && !INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (width))) 1071 error ("width of bit-field %qD has non-integral type %qT", value, 1072 TREE_TYPE (width)); 1073 DECL_INITIAL (value) = width; 1074 SET_DECL_C_BIT_FIELD (value); 1075 } 1076 1077 DECL_IN_AGGR_P (value) = 1; 1078 1079 if (attrlist) 1080 cplus_decl_attributes (&value, attrlist, /*flags=*/0); 1081 1082 return value; 1083 } 1084 1085 1086 /* Returns true iff ATTR is an attribute which needs to be applied at 1087 instantiation time rather than template definition time. */ 1088 1089 static bool 1090 is_late_template_attribute (tree attr, tree decl) 1091 { 1092 tree name = TREE_PURPOSE (attr); 1093 tree args = TREE_VALUE (attr); 1094 const struct attribute_spec *spec = lookup_attribute_spec (name); 1095 tree arg; 1096 1097 if (!spec) 1098 /* Unknown attribute. */ 1099 return false; 1100 1101 /* Attribute weak handling wants to write out assembly right away. */ 1102 if (is_attribute_p ("weak", name)) 1103 return true; 1104 1105 /* If any of the arguments are dependent expressions, we can't evaluate 1106 the attribute until instantiation time. */ 1107 for (arg = args; arg; arg = TREE_CHAIN (arg)) 1108 { 1109 tree t = TREE_VALUE (arg); 1110 1111 /* If the first attribute argument is an identifier, only consider 1112 second and following arguments. Attributes like mode, format, 1113 cleanup and several target specific attributes aren't late 1114 just because they have an IDENTIFIER_NODE as first argument. */ 1115 if (arg == args && TREE_CODE (t) == IDENTIFIER_NODE) 1116 continue; 1117 1118 if (value_dependent_expression_p (t) 1119 || type_dependent_expression_p (t)) 1120 return true; 1121 } 1122 1123 if (TREE_CODE (decl) == TYPE_DECL 1124 || TYPE_P (decl) 1125 || spec->type_required) 1126 { 1127 tree type = TYPE_P (decl) ? decl : TREE_TYPE (decl); 1128 1129 /* We can't apply any attributes to a completely unknown type until 1130 instantiation time. */ 1131 enum tree_code code = TREE_CODE (type); 1132 if (code == TEMPLATE_TYPE_PARM 1133 || code == BOUND_TEMPLATE_TEMPLATE_PARM 1134 || code == TYPENAME_TYPE) 1135 return true; 1136 /* Also defer most attributes on dependent types. This is not 1137 necessary in all cases, but is the better default. */ 1138 else if (dependent_type_p (type) 1139 /* But attribute visibility specifically works on 1140 templates. */ 1141 && !is_attribute_p ("visibility", name)) 1142 return true; 1143 else 1144 return false; 1145 } 1146 else 1147 return false; 1148 } 1149 1150 /* ATTR_P is a list of attributes. Remove any attributes which need to be 1151 applied at instantiation time and return them. If IS_DEPENDENT is true, 1152 the declaration itself is dependent, so all attributes should be applied 1153 at instantiation time. */ 1154 1155 static tree 1156 splice_template_attributes (tree *attr_p, tree decl) 1157 { 1158 tree *p = attr_p; 1159 tree late_attrs = NULL_TREE; 1160 tree *q = &late_attrs; 1161 1162 if (!p) 1163 return NULL_TREE; 1164 1165 for (; *p; ) 1166 { 1167 if (is_late_template_attribute (*p, decl)) 1168 { 1169 ATTR_IS_DEPENDENT (*p) = 1; 1170 *q = *p; 1171 *p = TREE_CHAIN (*p); 1172 q = &TREE_CHAIN (*q); 1173 *q = NULL_TREE; 1174 } 1175 else 1176 p = &TREE_CHAIN (*p); 1177 } 1178 1179 return late_attrs; 1180 } 1181 1182 /* Remove any late attributes from the list in ATTR_P and attach them to 1183 DECL_P. */ 1184 1185 static void 1186 save_template_attributes (tree *attr_p, tree *decl_p) 1187 { 1188 tree late_attrs = splice_template_attributes (attr_p, *decl_p); 1189 tree *q; 1190 tree old_attrs = NULL_TREE; 1191 1192 if (!late_attrs) 1193 return; 1194 1195 if (DECL_P (*decl_p)) 1196 q = &DECL_ATTRIBUTES (*decl_p); 1197 else 1198 q = &TYPE_ATTRIBUTES (*decl_p); 1199 1200 old_attrs = *q; 1201 1202 /* Merge the late attributes at the beginning with the attribute 1203 list. */ 1204 late_attrs = merge_attributes (late_attrs, *q); 1205 *q = late_attrs; 1206 1207 if (!DECL_P (*decl_p) && *decl_p == TYPE_MAIN_VARIANT (*decl_p)) 1208 { 1209 /* We've added new attributes directly to the main variant, so 1210 now we need to update all of the other variants to include 1211 these new attributes. */ 1212 tree variant; 1213 for (variant = TYPE_NEXT_VARIANT (*decl_p); variant; 1214 variant = TYPE_NEXT_VARIANT (variant)) 1215 { 1216 gcc_assert (TYPE_ATTRIBUTES (variant) == old_attrs); 1217 TYPE_ATTRIBUTES (variant) = TYPE_ATTRIBUTES (*decl_p); 1218 } 1219 } 1220 } 1221 1222 /* Like reconstruct_complex_type, but handle also template trees. */ 1223 1224 tree 1225 cp_reconstruct_complex_type (tree type, tree bottom) 1226 { 1227 tree inner, outer; 1228 1229 if (TREE_CODE (type) == POINTER_TYPE) 1230 { 1231 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1232 outer = build_pointer_type_for_mode (inner, TYPE_MODE (type), 1233 TYPE_REF_CAN_ALIAS_ALL (type)); 1234 } 1235 else if (TREE_CODE (type) == REFERENCE_TYPE) 1236 { 1237 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1238 outer = build_reference_type_for_mode (inner, TYPE_MODE (type), 1239 TYPE_REF_CAN_ALIAS_ALL (type)); 1240 } 1241 else if (TREE_CODE (type) == ARRAY_TYPE) 1242 { 1243 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1244 outer = build_cplus_array_type (inner, TYPE_DOMAIN (type)); 1245 /* Don't call cp_build_qualified_type on ARRAY_TYPEs, the 1246 element type qualification will be handled by the recursive 1247 cp_reconstruct_complex_type call and cp_build_qualified_type 1248 for ARRAY_TYPEs changes the element type. */ 1249 return outer; 1250 } 1251 else if (TREE_CODE (type) == FUNCTION_TYPE) 1252 { 1253 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1254 outer = build_function_type (inner, TYPE_ARG_TYPES (type)); 1255 outer = apply_memfn_quals (outer, type_memfn_quals (type)); 1256 } 1257 else if (TREE_CODE (type) == METHOD_TYPE) 1258 { 1259 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1260 /* The build_method_type_directly() routine prepends 'this' to argument list, 1261 so we must compensate by getting rid of it. */ 1262 outer 1263 = build_method_type_directly 1264 (class_of_this_parm (type), inner, 1265 TREE_CHAIN (TYPE_ARG_TYPES (type))); 1266 } 1267 else if (TREE_CODE (type) == OFFSET_TYPE) 1268 { 1269 inner = cp_reconstruct_complex_type (TREE_TYPE (type), bottom); 1270 outer = build_offset_type (TYPE_OFFSET_BASETYPE (type), inner); 1271 } 1272 else 1273 return bottom; 1274 1275 if (TYPE_ATTRIBUTES (type)) 1276 outer = cp_build_type_attribute_variant (outer, TYPE_ATTRIBUTES (type)); 1277 return cp_build_qualified_type (outer, cp_type_quals (type)); 1278 } 1279 1280 /* Replaces any constexpr expression that may be into the attributes 1281 arguments with their reduced value. */ 1282 1283 static void 1284 cp_check_const_attributes (tree attributes) 1285 { 1286 tree attr; 1287 for (attr = attributes; attr; attr = TREE_CHAIN (attr)) 1288 { 1289 tree arg; 1290 for (arg = TREE_VALUE (attr); arg; arg = TREE_CHAIN (arg)) 1291 { 1292 tree expr = TREE_VALUE (arg); 1293 if (EXPR_P (expr)) 1294 TREE_VALUE (arg) = maybe_constant_value (expr); 1295 } 1296 } 1297 } 1298 1299 /* Like decl_attributes, but handle C++ complexity. */ 1300 1301 void 1302 cplus_decl_attributes (tree *decl, tree attributes, int flags) 1303 { 1304 if (*decl == NULL_TREE || *decl == void_type_node 1305 || *decl == error_mark_node) 1306 return; 1307 1308 if (processing_template_decl) 1309 { 1310 if (check_for_bare_parameter_packs (attributes)) 1311 return; 1312 1313 save_template_attributes (&attributes, decl); 1314 } 1315 1316 cp_check_const_attributes (attributes); 1317 1318 if (TREE_CODE (*decl) == TEMPLATE_DECL) 1319 decl = &DECL_TEMPLATE_RESULT (*decl); 1320 1321 decl_attributes (decl, attributes, flags); 1322 1323 if (TREE_CODE (*decl) == TYPE_DECL) 1324 SET_IDENTIFIER_TYPE_VALUE (DECL_NAME (*decl), TREE_TYPE (*decl)); 1325 } 1326 1327 /* Walks through the namespace- or function-scope anonymous union 1328 OBJECT, with the indicated TYPE, building appropriate VAR_DECLs. 1329 Returns one of the fields for use in the mangled name. */ 1330 1331 static tree 1332 build_anon_union_vars (tree type, tree object) 1333 { 1334 tree main_decl = NULL_TREE; 1335 tree field; 1336 1337 /* Rather than write the code to handle the non-union case, 1338 just give an error. */ 1339 if (TREE_CODE (type) != UNION_TYPE) 1340 { 1341 error ("anonymous struct not inside named type"); 1342 return error_mark_node; 1343 } 1344 1345 for (field = TYPE_FIELDS (type); 1346 field != NULL_TREE; 1347 field = DECL_CHAIN (field)) 1348 { 1349 tree decl; 1350 tree ref; 1351 1352 if (DECL_ARTIFICIAL (field)) 1353 continue; 1354 if (TREE_CODE (field) != FIELD_DECL) 1355 { 1356 permerror (input_location, "%q+#D invalid; an anonymous union can only " 1357 "have non-static data members", field); 1358 continue; 1359 } 1360 1361 if (TREE_PRIVATE (field)) 1362 permerror (input_location, "private member %q+#D in anonymous union", field); 1363 else if (TREE_PROTECTED (field)) 1364 permerror (input_location, "protected member %q+#D in anonymous union", field); 1365 1366 if (processing_template_decl) 1367 ref = build_min_nt (COMPONENT_REF, object, 1368 DECL_NAME (field), NULL_TREE); 1369 else 1370 ref = build_class_member_access_expr (object, field, NULL_TREE, 1371 false, tf_warning_or_error); 1372 1373 if (DECL_NAME (field)) 1374 { 1375 tree base; 1376 1377 decl = build_decl (input_location, 1378 VAR_DECL, DECL_NAME (field), TREE_TYPE (field)); 1379 DECL_ANON_UNION_VAR_P (decl) = 1; 1380 DECL_ARTIFICIAL (decl) = 1; 1381 1382 base = get_base_address (object); 1383 TREE_PUBLIC (decl) = TREE_PUBLIC (base); 1384 TREE_STATIC (decl) = TREE_STATIC (base); 1385 DECL_EXTERNAL (decl) = DECL_EXTERNAL (base); 1386 1387 SET_DECL_VALUE_EXPR (decl, ref); 1388 DECL_HAS_VALUE_EXPR_P (decl) = 1; 1389 1390 decl = pushdecl (decl); 1391 } 1392 else if (ANON_AGGR_TYPE_P (TREE_TYPE (field))) 1393 decl = build_anon_union_vars (TREE_TYPE (field), ref); 1394 else 1395 decl = 0; 1396 1397 if (main_decl == NULL_TREE) 1398 main_decl = decl; 1399 } 1400 1401 return main_decl; 1402 } 1403 1404 /* Finish off the processing of a UNION_TYPE structure. If the union is an 1405 anonymous union, then all members must be laid out together. PUBLIC_P 1406 is nonzero if this union is not declared static. */ 1407 1408 void 1409 finish_anon_union (tree anon_union_decl) 1410 { 1411 tree type; 1412 tree main_decl; 1413 bool public_p; 1414 1415 if (anon_union_decl == error_mark_node) 1416 return; 1417 1418 type = TREE_TYPE (anon_union_decl); 1419 public_p = TREE_PUBLIC (anon_union_decl); 1420 1421 /* The VAR_DECL's context is the same as the TYPE's context. */ 1422 DECL_CONTEXT (anon_union_decl) = DECL_CONTEXT (TYPE_NAME (type)); 1423 1424 if (TYPE_FIELDS (type) == NULL_TREE) 1425 return; 1426 1427 if (public_p) 1428 { 1429 error ("namespace-scope anonymous aggregates must be static"); 1430 return; 1431 } 1432 1433 main_decl = build_anon_union_vars (type, anon_union_decl); 1434 if (main_decl == error_mark_node) 1435 return; 1436 if (main_decl == NULL_TREE) 1437 { 1438 warning (0, "anonymous union with no members"); 1439 return; 1440 } 1441 1442 if (!processing_template_decl) 1443 { 1444 /* Use main_decl to set the mangled name. */ 1445 DECL_NAME (anon_union_decl) = DECL_NAME (main_decl); 1446 maybe_commonize_var (anon_union_decl); 1447 if (TREE_STATIC (anon_union_decl) || DECL_EXTERNAL (anon_union_decl)) 1448 mangle_decl (anon_union_decl); 1449 DECL_NAME (anon_union_decl) = NULL_TREE; 1450 } 1451 1452 pushdecl (anon_union_decl); 1453 if (building_stmt_list_p () 1454 && at_function_scope_p ()) 1455 add_decl_expr (anon_union_decl); 1456 else if (!processing_template_decl) 1457 rest_of_decl_compilation (anon_union_decl, 1458 toplevel_bindings_p (), at_eof); 1459 } 1460 1461 /* Auxiliary functions to make type signatures for 1462 `operator new' and `operator delete' correspond to 1463 what compiler will be expecting. */ 1464 1465 tree 1466 coerce_new_type (tree type) 1467 { 1468 int e = 0; 1469 tree args = TYPE_ARG_TYPES (type); 1470 1471 gcc_assert (TREE_CODE (type) == FUNCTION_TYPE); 1472 1473 if (!same_type_p (TREE_TYPE (type), ptr_type_node)) 1474 { 1475 e = 1; 1476 error ("%<operator new%> must return type %qT", ptr_type_node); 1477 } 1478 1479 if (args && args != void_list_node) 1480 { 1481 if (TREE_PURPOSE (args)) 1482 { 1483 /* [basic.stc.dynamic.allocation] 1484 1485 The first parameter shall not have an associated default 1486 argument. */ 1487 error ("the first parameter of %<operator new%> cannot " 1488 "have a default argument"); 1489 /* Throw away the default argument. */ 1490 TREE_PURPOSE (args) = NULL_TREE; 1491 } 1492 1493 if (!same_type_p (TREE_VALUE (args), size_type_node)) 1494 { 1495 e = 2; 1496 args = TREE_CHAIN (args); 1497 } 1498 } 1499 else 1500 e = 2; 1501 1502 if (e == 2) 1503 permerror (input_location, "%<operator new%> takes type %<size_t%> (%qT) " 1504 "as first parameter", size_type_node); 1505 1506 switch (e) 1507 { 1508 case 2: 1509 args = tree_cons (NULL_TREE, size_type_node, args); 1510 /* Fall through. */ 1511 case 1: 1512 type = build_exception_variant 1513 (build_function_type (ptr_type_node, args), 1514 TYPE_RAISES_EXCEPTIONS (type)); 1515 /* Fall through. */ 1516 default:; 1517 } 1518 return type; 1519 } 1520 1521 tree 1522 coerce_delete_type (tree type) 1523 { 1524 int e = 0; 1525 tree args = TYPE_ARG_TYPES (type); 1526 1527 gcc_assert (TREE_CODE (type) == FUNCTION_TYPE); 1528 1529 if (!same_type_p (TREE_TYPE (type), void_type_node)) 1530 { 1531 e = 1; 1532 error ("%<operator delete%> must return type %qT", void_type_node); 1533 } 1534 1535 if (!args || args == void_list_node 1536 || !same_type_p (TREE_VALUE (args), ptr_type_node)) 1537 { 1538 e = 2; 1539 if (args && args != void_list_node) 1540 args = TREE_CHAIN (args); 1541 error ("%<operator delete%> takes type %qT as first parameter", 1542 ptr_type_node); 1543 } 1544 switch (e) 1545 { 1546 case 2: 1547 args = tree_cons (NULL_TREE, ptr_type_node, args); 1548 /* Fall through. */ 1549 case 1: 1550 type = build_exception_variant 1551 (build_function_type (void_type_node, args), 1552 TYPE_RAISES_EXCEPTIONS (type)); 1553 /* Fall through. */ 1554 default:; 1555 } 1556 1557 return type; 1558 } 1559 1560 /* DECL is a VAR_DECL for a vtable: walk through the entries in the vtable 1561 and mark them as needed. */ 1562 1563 static void 1564 mark_vtable_entries (tree decl) 1565 { 1566 tree fnaddr; 1567 unsigned HOST_WIDE_INT idx; 1568 1569 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (DECL_INITIAL (decl)), 1570 idx, fnaddr) 1571 { 1572 tree fn; 1573 1574 STRIP_NOPS (fnaddr); 1575 1576 if (TREE_CODE (fnaddr) != ADDR_EXPR 1577 && TREE_CODE (fnaddr) != FDESC_EXPR) 1578 /* This entry is an offset: a virtual base class offset, a 1579 virtual call offset, an RTTI offset, etc. */ 1580 continue; 1581 1582 fn = TREE_OPERAND (fnaddr, 0); 1583 TREE_ADDRESSABLE (fn) = 1; 1584 /* When we don't have vcall offsets, we output thunks whenever 1585 we output the vtables that contain them. With vcall offsets, 1586 we know all the thunks we'll need when we emit a virtual 1587 function, so we emit the thunks there instead. */ 1588 if (DECL_THUNK_P (fn)) 1589 use_thunk (fn, /*emit_p=*/0); 1590 mark_used (fn); 1591 } 1592 } 1593 1594 /* Set DECL up to have the closest approximation of "initialized common" 1595 linkage available. */ 1596 1597 void 1598 comdat_linkage (tree decl) 1599 { 1600 if (flag_weak) 1601 make_decl_one_only (decl, cxx_comdat_group (decl)); 1602 else if (TREE_CODE (decl) == FUNCTION_DECL 1603 || (TREE_CODE (decl) == VAR_DECL && DECL_ARTIFICIAL (decl))) 1604 /* We can just emit function and compiler-generated variables 1605 statically; having multiple copies is (for the most part) only 1606 a waste of space. 1607 1608 There are two correctness issues, however: the address of a 1609 template instantiation with external linkage should be the 1610 same, independent of what translation unit asks for the 1611 address, and this will not hold when we emit multiple copies of 1612 the function. However, there's little else we can do. 1613 1614 Also, by default, the typeinfo implementation assumes that 1615 there will be only one copy of the string used as the name for 1616 each type. Therefore, if weak symbols are unavailable, the 1617 run-time library should perform a more conservative check; it 1618 should perform a string comparison, rather than an address 1619 comparison. */ 1620 TREE_PUBLIC (decl) = 0; 1621 else 1622 { 1623 /* Static data member template instantiations, however, cannot 1624 have multiple copies. */ 1625 if (DECL_INITIAL (decl) == 0 1626 || DECL_INITIAL (decl) == error_mark_node) 1627 DECL_COMMON (decl) = 1; 1628 else if (EMPTY_CONSTRUCTOR_P (DECL_INITIAL (decl))) 1629 { 1630 DECL_COMMON (decl) = 1; 1631 DECL_INITIAL (decl) = error_mark_node; 1632 } 1633 else if (!DECL_EXPLICIT_INSTANTIATION (decl)) 1634 { 1635 /* We can't do anything useful; leave vars for explicit 1636 instantiation. */ 1637 DECL_EXTERNAL (decl) = 1; 1638 DECL_NOT_REALLY_EXTERN (decl) = 0; 1639 } 1640 } 1641 1642 DECL_COMDAT (decl) = 1; 1643 } 1644 1645 /* For win32 we also want to put explicit instantiations in 1646 linkonce sections, so that they will be merged with implicit 1647 instantiations; otherwise we get duplicate symbol errors. 1648 For Darwin we do not want explicit instantiations to be 1649 linkonce. */ 1650 1651 void 1652 maybe_make_one_only (tree decl) 1653 { 1654 /* We used to say that this was not necessary on targets that support weak 1655 symbols, because the implicit instantiations will defer to the explicit 1656 one. However, that's not actually the case in SVR4; a strong definition 1657 after a weak one is an error. Also, not making explicit 1658 instantiations one_only means that we can end up with two copies of 1659 some template instantiations. */ 1660 if (! flag_weak) 1661 return; 1662 1663 /* We can't set DECL_COMDAT on functions, or cp_finish_file will think 1664 we can get away with not emitting them if they aren't used. We need 1665 to for variables so that cp_finish_decl will update their linkage, 1666 because their DECL_INITIAL may not have been set properly yet. */ 1667 1668 if (!TARGET_WEAK_NOT_IN_ARCHIVE_TOC 1669 || (! DECL_EXPLICIT_INSTANTIATION (decl) 1670 && ! DECL_TEMPLATE_SPECIALIZATION (decl))) 1671 { 1672 make_decl_one_only (decl, cxx_comdat_group (decl)); 1673 1674 if (TREE_CODE (decl) == VAR_DECL) 1675 { 1676 DECL_COMDAT (decl) = 1; 1677 /* Mark it needed so we don't forget to emit it. */ 1678 mark_decl_referenced (decl); 1679 } 1680 } 1681 } 1682 1683 /* Returns true iff DECL, a FUNCTION_DECL or VAR_DECL, has vague linkage. 1684 This predicate will give the right answer during parsing of the 1685 function, which other tests may not. */ 1686 1687 bool 1688 vague_linkage_p (tree decl) 1689 { 1690 /* Unfortunately, import_export_decl has not always been called 1691 before the function is processed, so we cannot simply check 1692 DECL_COMDAT. */ 1693 return (DECL_COMDAT (decl) 1694 || (((TREE_CODE (decl) == FUNCTION_DECL 1695 && DECL_DECLARED_INLINE_P (decl)) 1696 || (DECL_LANG_SPECIFIC (decl) 1697 && DECL_TEMPLATE_INSTANTIATION (decl))) 1698 && TREE_PUBLIC (decl))); 1699 } 1700 1701 /* Determine whether or not we want to specifically import or export CTYPE, 1702 using various heuristics. */ 1703 1704 static void 1705 import_export_class (tree ctype) 1706 { 1707 /* -1 for imported, 1 for exported. */ 1708 int import_export = 0; 1709 1710 /* It only makes sense to call this function at EOF. The reason is 1711 that this function looks at whether or not the first non-inline 1712 non-abstract virtual member function has been defined in this 1713 translation unit. But, we can't possibly know that until we've 1714 seen the entire translation unit. */ 1715 gcc_assert (at_eof); 1716 1717 if (CLASSTYPE_INTERFACE_KNOWN (ctype)) 1718 return; 1719 1720 /* If MULTIPLE_SYMBOL_SPACES is set and we saw a #pragma interface, 1721 we will have CLASSTYPE_INTERFACE_ONLY set but not 1722 CLASSTYPE_INTERFACE_KNOWN. In that case, we don't want to use this 1723 heuristic because someone will supply a #pragma implementation 1724 elsewhere, and deducing it here would produce a conflict. */ 1725 if (CLASSTYPE_INTERFACE_ONLY (ctype)) 1726 return; 1727 1728 if (lookup_attribute ("dllimport", TYPE_ATTRIBUTES (ctype))) 1729 import_export = -1; 1730 else if (lookup_attribute ("dllexport", TYPE_ATTRIBUTES (ctype))) 1731 import_export = 1; 1732 else if (CLASSTYPE_IMPLICIT_INSTANTIATION (ctype) 1733 && !flag_implicit_templates) 1734 /* For a template class, without -fimplicit-templates, check the 1735 repository. If the virtual table is assigned to this 1736 translation unit, then export the class; otherwise, import 1737 it. */ 1738 import_export = repo_export_class_p (ctype) ? 1 : -1; 1739 else if (TYPE_POLYMORPHIC_P (ctype)) 1740 { 1741 /* The ABI specifies that the virtual table and associated 1742 information are emitted with the key method, if any. */ 1743 tree method = CLASSTYPE_KEY_METHOD (ctype); 1744 /* If weak symbol support is not available, then we must be 1745 careful not to emit the vtable when the key function is 1746 inline. An inline function can be defined in multiple 1747 translation units. If we were to emit the vtable in each 1748 translation unit containing a definition, we would get 1749 multiple definition errors at link-time. */ 1750 if (method && (flag_weak || ! DECL_DECLARED_INLINE_P (method))) 1751 import_export = (DECL_REALLY_EXTERN (method) ? -1 : 1); 1752 } 1753 1754 /* When MULTIPLE_SYMBOL_SPACES is set, we cannot count on seeing 1755 a definition anywhere else. */ 1756 if (MULTIPLE_SYMBOL_SPACES && import_export == -1) 1757 import_export = 0; 1758 1759 /* Allow back ends the chance to overrule the decision. */ 1760 if (targetm.cxx.import_export_class) 1761 import_export = targetm.cxx.import_export_class (ctype, import_export); 1762 1763 if (import_export) 1764 { 1765 SET_CLASSTYPE_INTERFACE_KNOWN (ctype); 1766 CLASSTYPE_INTERFACE_ONLY (ctype) = (import_export < 0); 1767 } 1768 } 1769 1770 /* Return true if VAR has already been provided to the back end; in that 1771 case VAR should not be modified further by the front end. */ 1772 static bool 1773 var_finalized_p (tree var) 1774 { 1775 return varpool_node (var)->finalized; 1776 } 1777 1778 /* DECL is a VAR_DECL or FUNCTION_DECL which, for whatever reason, 1779 must be emitted in this translation unit. Mark it as such. */ 1780 1781 void 1782 mark_needed (tree decl) 1783 { 1784 /* It's possible that we no longer need to set 1785 TREE_SYMBOL_REFERENCED here directly, but doing so is 1786 harmless. */ 1787 TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)) = 1; 1788 mark_decl_referenced (decl); 1789 } 1790 1791 /* DECL is either a FUNCTION_DECL or a VAR_DECL. This function 1792 returns true if a definition of this entity should be provided in 1793 this object file. Callers use this function to determine whether 1794 or not to let the back end know that a definition of DECL is 1795 available in this translation unit. */ 1796 1797 bool 1798 decl_needed_p (tree decl) 1799 { 1800 gcc_assert (TREE_CODE (decl) == VAR_DECL 1801 || TREE_CODE (decl) == FUNCTION_DECL); 1802 /* This function should only be called at the end of the translation 1803 unit. We cannot be sure of whether or not something will be 1804 COMDAT until that point. */ 1805 gcc_assert (at_eof); 1806 1807 /* All entities with external linkage that are not COMDAT should be 1808 emitted; they may be referred to from other object files. */ 1809 if (TREE_PUBLIC (decl) && !DECL_COMDAT (decl)) 1810 return true; 1811 /* If this entity was used, let the back end see it; it will decide 1812 whether or not to emit it into the object file. */ 1813 if (TREE_USED (decl) 1814 || (DECL_ASSEMBLER_NAME_SET_P (decl) 1815 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl)))) 1816 return true; 1817 /* Functions marked "dllexport" must be emitted so that they are 1818 visible to other DLLs. */ 1819 if (flag_keep_inline_dllexport 1820 && lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl))) 1821 return true; 1822 /* Otherwise, DECL does not need to be emitted -- yet. A subsequent 1823 reference to DECL might cause it to be emitted later. */ 1824 return false; 1825 } 1826 1827 /* If necessary, write out the vtables for the dynamic class CTYPE. 1828 Returns true if any vtables were emitted. */ 1829 1830 static bool 1831 maybe_emit_vtables (tree ctype) 1832 { 1833 tree vtbl; 1834 tree primary_vtbl; 1835 int needed = 0; 1836 struct varpool_node *current = NULL, *last = NULL, *first = NULL; 1837 1838 /* If the vtables for this class have already been emitted there is 1839 nothing more to do. */ 1840 primary_vtbl = CLASSTYPE_VTABLES (ctype); 1841 if (var_finalized_p (primary_vtbl)) 1842 return false; 1843 /* Ignore dummy vtables made by get_vtable_decl. */ 1844 if (TREE_TYPE (primary_vtbl) == void_type_node) 1845 return false; 1846 1847 /* On some targets, we cannot determine the key method until the end 1848 of the translation unit -- which is when this function is 1849 called. */ 1850 if (!targetm.cxx.key_method_may_be_inline ()) 1851 determine_key_method (ctype); 1852 1853 /* See if any of the vtables are needed. */ 1854 for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = DECL_CHAIN (vtbl)) 1855 { 1856 import_export_decl (vtbl); 1857 if (DECL_NOT_REALLY_EXTERN (vtbl) && decl_needed_p (vtbl)) 1858 needed = 1; 1859 } 1860 if (!needed) 1861 { 1862 /* If the references to this class' vtables are optimized away, 1863 still emit the appropriate debugging information. See 1864 dfs_debug_mark. */ 1865 if (DECL_COMDAT (primary_vtbl) 1866 && CLASSTYPE_DEBUG_REQUESTED (ctype)) 1867 note_debug_info_needed (ctype); 1868 return false; 1869 } 1870 1871 /* The ABI requires that we emit all of the vtables if we emit any 1872 of them. */ 1873 for (vtbl = CLASSTYPE_VTABLES (ctype); vtbl; vtbl = DECL_CHAIN (vtbl)) 1874 { 1875 /* Mark entities references from the virtual table as used. */ 1876 mark_vtable_entries (vtbl); 1877 1878 if (TREE_TYPE (DECL_INITIAL (vtbl)) == 0) 1879 { 1880 VEC(tree,gc)* cleanups = NULL; 1881 tree expr = store_init_value (vtbl, DECL_INITIAL (vtbl), &cleanups, 1882 LOOKUP_NORMAL); 1883 1884 /* It had better be all done at compile-time. */ 1885 gcc_assert (!expr && !cleanups); 1886 } 1887 1888 /* Write it out. */ 1889 DECL_EXTERNAL (vtbl) = 0; 1890 rest_of_decl_compilation (vtbl, 1, 1); 1891 1892 /* Because we're only doing syntax-checking, we'll never end up 1893 actually marking the variable as written. */ 1894 if (flag_syntax_only) 1895 TREE_ASM_WRITTEN (vtbl) = 1; 1896 else if (DECL_COMDAT (vtbl)) 1897 { 1898 current = varpool_node (vtbl); 1899 if (last) 1900 last->same_comdat_group = current; 1901 last = current; 1902 if (!first) 1903 first = current; 1904 } 1905 } 1906 1907 if (first != last) 1908 last->same_comdat_group = first; 1909 1910 /* Since we're writing out the vtable here, also write the debug 1911 info. */ 1912 note_debug_info_needed (ctype); 1913 1914 return true; 1915 } 1916 1917 /* A special return value from type_visibility meaning internal 1918 linkage. */ 1919 1920 enum { VISIBILITY_ANON = VISIBILITY_INTERNAL+1 }; 1921 1922 /* walk_tree helper function for type_visibility. */ 1923 1924 static tree 1925 min_vis_r (tree *tp, int *walk_subtrees, void *data) 1926 { 1927 int *vis_p = (int *)data; 1928 if (! TYPE_P (*tp)) 1929 { 1930 *walk_subtrees = 0; 1931 } 1932 else if (TAGGED_TYPE_P (*tp) 1933 && !TREE_PUBLIC (TYPE_MAIN_DECL (*tp))) 1934 { 1935 *vis_p = VISIBILITY_ANON; 1936 return *tp; 1937 } 1938 else if (CLASS_TYPE_P (*tp) 1939 && CLASSTYPE_VISIBILITY (*tp) > *vis_p) 1940 *vis_p = CLASSTYPE_VISIBILITY (*tp); 1941 return NULL; 1942 } 1943 1944 /* Returns the visibility of TYPE, which is the minimum visibility of its 1945 component types. */ 1946 1947 static int 1948 type_visibility (tree type) 1949 { 1950 int vis = VISIBILITY_DEFAULT; 1951 cp_walk_tree_without_duplicates (&type, min_vis_r, &vis); 1952 return vis; 1953 } 1954 1955 /* Limit the visibility of DECL to VISIBILITY, if not explicitly 1956 specified (or if VISIBILITY is static). If TMPL is true, this 1957 constraint is for a template argument, and takes precedence 1958 over explicitly-specified visibility on the template. */ 1959 1960 static void 1961 constrain_visibility (tree decl, int visibility, bool tmpl) 1962 { 1963 if (visibility == VISIBILITY_ANON) 1964 { 1965 /* extern "C" declarations aren't affected by the anonymous 1966 namespace. */ 1967 if (!DECL_EXTERN_C_P (decl)) 1968 { 1969 TREE_PUBLIC (decl) = 0; 1970 DECL_WEAK (decl) = 0; 1971 DECL_COMMON (decl) = 0; 1972 DECL_COMDAT_GROUP (decl) = NULL_TREE; 1973 DECL_INTERFACE_KNOWN (decl) = 1; 1974 if (DECL_LANG_SPECIFIC (decl)) 1975 DECL_NOT_REALLY_EXTERN (decl) = 1; 1976 } 1977 } 1978 else if (visibility > DECL_VISIBILITY (decl) 1979 && (tmpl || !DECL_VISIBILITY_SPECIFIED (decl))) 1980 { 1981 DECL_VISIBILITY (decl) = (enum symbol_visibility) visibility; 1982 /* This visibility was not specified. */ 1983 DECL_VISIBILITY_SPECIFIED (decl) = false; 1984 } 1985 } 1986 1987 /* Constrain the visibility of DECL based on the visibility of its template 1988 arguments. */ 1989 1990 static void 1991 constrain_visibility_for_template (tree decl, tree targs) 1992 { 1993 /* If this is a template instantiation, check the innermost 1994 template args for visibility constraints. The outer template 1995 args are covered by the class check. */ 1996 tree args = INNERMOST_TEMPLATE_ARGS (targs); 1997 int i; 1998 for (i = TREE_VEC_LENGTH (args); i > 0; --i) 1999 { 2000 int vis = 0; 2001 2002 tree arg = TREE_VEC_ELT (args, i-1); 2003 if (TYPE_P (arg)) 2004 vis = type_visibility (arg); 2005 else if (TREE_TYPE (arg) && POINTER_TYPE_P (TREE_TYPE (arg))) 2006 { 2007 STRIP_NOPS (arg); 2008 if (TREE_CODE (arg) == ADDR_EXPR) 2009 arg = TREE_OPERAND (arg, 0); 2010 if (TREE_CODE (arg) == VAR_DECL 2011 || TREE_CODE (arg) == FUNCTION_DECL) 2012 { 2013 if (! TREE_PUBLIC (arg)) 2014 vis = VISIBILITY_ANON; 2015 else 2016 vis = DECL_VISIBILITY (arg); 2017 } 2018 } 2019 if (vis) 2020 constrain_visibility (decl, vis, true); 2021 } 2022 } 2023 2024 /* Like c_determine_visibility, but with additional C++-specific 2025 behavior. 2026 2027 Function-scope entities can rely on the function's visibility because 2028 it is set in start_preparsed_function. 2029 2030 Class-scope entities cannot rely on the class's visibility until the end 2031 of the enclosing class definition. 2032 2033 Note that because namespaces have multiple independent definitions, 2034 namespace visibility is handled elsewhere using the #pragma visibility 2035 machinery rather than by decorating the namespace declaration. 2036 2037 The goal is for constraints from the type to give a diagnostic, and 2038 other constraints to be applied silently. */ 2039 2040 void 2041 determine_visibility (tree decl) 2042 { 2043 tree class_type = NULL_TREE; 2044 bool use_template; 2045 bool orig_visibility_specified; 2046 enum symbol_visibility orig_visibility; 2047 2048 /* Remember that all decls get VISIBILITY_DEFAULT when built. */ 2049 2050 /* Only relevant for names with external linkage. */ 2051 if (!TREE_PUBLIC (decl)) 2052 return; 2053 2054 /* Cloned constructors and destructors get the same visibility as 2055 the underlying function. That should be set up in 2056 maybe_clone_body. */ 2057 gcc_assert (!DECL_CLONED_FUNCTION_P (decl)); 2058 2059 orig_visibility_specified = DECL_VISIBILITY_SPECIFIED (decl); 2060 orig_visibility = DECL_VISIBILITY (decl); 2061 2062 if (TREE_CODE (decl) == TYPE_DECL) 2063 { 2064 if (CLASS_TYPE_P (TREE_TYPE (decl))) 2065 use_template = CLASSTYPE_USE_TEMPLATE (TREE_TYPE (decl)); 2066 else if (TYPE_TEMPLATE_INFO (TREE_TYPE (decl))) 2067 use_template = 1; 2068 else 2069 use_template = 0; 2070 } 2071 else if (DECL_LANG_SPECIFIC (decl)) 2072 use_template = DECL_USE_TEMPLATE (decl); 2073 else 2074 use_template = 0; 2075 2076 /* If DECL is a member of a class, visibility specifiers on the 2077 class can influence the visibility of the DECL. */ 2078 if (DECL_CLASS_SCOPE_P (decl)) 2079 class_type = DECL_CONTEXT (decl); 2080 else 2081 { 2082 /* Not a class member. */ 2083 2084 /* Virtual tables have DECL_CONTEXT set to their associated class, 2085 so they are automatically handled above. */ 2086 gcc_assert (TREE_CODE (decl) != VAR_DECL 2087 || !DECL_VTABLE_OR_VTT_P (decl)); 2088 2089 if (DECL_FUNCTION_SCOPE_P (decl) && ! DECL_VISIBILITY_SPECIFIED (decl)) 2090 { 2091 /* Local statics and classes get the visibility of their 2092 containing function by default, except that 2093 -fvisibility-inlines-hidden doesn't affect them. */ 2094 tree fn = DECL_CONTEXT (decl); 2095 if (DECL_VISIBILITY_SPECIFIED (fn)) 2096 { 2097 DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn); 2098 DECL_VISIBILITY_SPECIFIED (decl) = 2099 DECL_VISIBILITY_SPECIFIED (fn); 2100 } 2101 else 2102 { 2103 if (DECL_CLASS_SCOPE_P (fn)) 2104 determine_visibility_from_class (decl, DECL_CONTEXT (fn)); 2105 else if (determine_hidden_inline (fn)) 2106 { 2107 DECL_VISIBILITY (decl) = default_visibility; 2108 DECL_VISIBILITY_SPECIFIED (decl) = 2109 visibility_options.inpragma; 2110 } 2111 else 2112 { 2113 DECL_VISIBILITY (decl) = DECL_VISIBILITY (fn); 2114 DECL_VISIBILITY_SPECIFIED (decl) = 2115 DECL_VISIBILITY_SPECIFIED (fn); 2116 } 2117 } 2118 2119 /* Local classes in templates have CLASSTYPE_USE_TEMPLATE set, 2120 but have no TEMPLATE_INFO, so don't try to check it. */ 2121 use_template = 0; 2122 } 2123 else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl) 2124 && flag_visibility_ms_compat) 2125 { 2126 /* Under -fvisibility-ms-compat, types are visible by default, 2127 even though their contents aren't. */ 2128 tree underlying_type = TREE_TYPE (DECL_NAME (decl)); 2129 int underlying_vis = type_visibility (underlying_type); 2130 if (underlying_vis == VISIBILITY_ANON 2131 || (CLASS_TYPE_P (underlying_type) 2132 && CLASSTYPE_VISIBILITY_SPECIFIED (underlying_type))) 2133 constrain_visibility (decl, underlying_vis, false); 2134 else 2135 DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT; 2136 } 2137 else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl)) 2138 { 2139 /* tinfo visibility is based on the type it's for. */ 2140 constrain_visibility 2141 (decl, type_visibility (TREE_TYPE (DECL_NAME (decl))), false); 2142 2143 /* Give the target a chance to override the visibility associated 2144 with DECL. */ 2145 if (TREE_PUBLIC (decl) 2146 && !DECL_REALLY_EXTERN (decl) 2147 && CLASS_TYPE_P (TREE_TYPE (DECL_NAME (decl))) 2148 && !CLASSTYPE_VISIBILITY_SPECIFIED (TREE_TYPE (DECL_NAME (decl)))) 2149 targetm.cxx.determine_class_data_visibility (decl); 2150 } 2151 else if (use_template) 2152 /* Template instantiations and specializations get visibility based 2153 on their template unless they override it with an attribute. */; 2154 else if (! DECL_VISIBILITY_SPECIFIED (decl)) 2155 { 2156 if (determine_hidden_inline (decl)) 2157 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN; 2158 else 2159 { 2160 /* Set default visibility to whatever the user supplied with 2161 #pragma GCC visibility or a namespace visibility attribute. */ 2162 DECL_VISIBILITY (decl) = default_visibility; 2163 DECL_VISIBILITY_SPECIFIED (decl) = visibility_options.inpragma; 2164 } 2165 } 2166 } 2167 2168 if (use_template) 2169 { 2170 /* If the specialization doesn't specify visibility, use the 2171 visibility from the template. */ 2172 tree tinfo = (TREE_CODE (decl) == TYPE_DECL 2173 ? TYPE_TEMPLATE_INFO (TREE_TYPE (decl)) 2174 : DECL_TEMPLATE_INFO (decl)); 2175 tree args = TI_ARGS (tinfo); 2176 tree attribs = (TREE_CODE (decl) == TYPE_DECL 2177 ? TYPE_ATTRIBUTES (TREE_TYPE (decl)) 2178 : DECL_ATTRIBUTES (decl)); 2179 2180 if (args != error_mark_node 2181 /* Template argument visibility outweighs #pragma or namespace 2182 visibility, but not an explicit attribute. */ 2183 && !lookup_attribute ("visibility", attribs)) 2184 { 2185 int depth = TMPL_ARGS_DEPTH (args); 2186 tree pattern = DECL_TEMPLATE_RESULT (TI_TEMPLATE (tinfo)); 2187 2188 if (!DECL_VISIBILITY_SPECIFIED (decl)) 2189 { 2190 if (!DECL_VISIBILITY_SPECIFIED (pattern) 2191 && determine_hidden_inline (decl)) 2192 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN; 2193 else 2194 { 2195 DECL_VISIBILITY (decl) = DECL_VISIBILITY (pattern); 2196 DECL_VISIBILITY_SPECIFIED (decl) 2197 = DECL_VISIBILITY_SPECIFIED (pattern); 2198 } 2199 } 2200 2201 /* FIXME should TMPL_ARGS_DEPTH really return 1 for null input? */ 2202 if (args && depth > template_class_depth (class_type)) 2203 /* Limit visibility based on its template arguments. */ 2204 constrain_visibility_for_template (decl, args); 2205 } 2206 } 2207 2208 if (class_type) 2209 determine_visibility_from_class (decl, class_type); 2210 2211 if (decl_anon_ns_mem_p (decl)) 2212 /* Names in an anonymous namespace get internal linkage. 2213 This might change once we implement export. */ 2214 constrain_visibility (decl, VISIBILITY_ANON, false); 2215 else if (TREE_CODE (decl) != TYPE_DECL) 2216 { 2217 /* Propagate anonymity from type to decl. */ 2218 int tvis = type_visibility (TREE_TYPE (decl)); 2219 if (tvis == VISIBILITY_ANON 2220 || ! DECL_VISIBILITY_SPECIFIED (decl)) 2221 constrain_visibility (decl, tvis, false); 2222 } 2223 else if (no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/true)) 2224 /* DR 757: A type without linkage shall not be used as the type of a 2225 variable or function with linkage, unless 2226 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or 2227 o the variable or function is not used (3.2 [basic.def.odr]) or is 2228 defined in the same translation unit. 2229 2230 Since non-extern "C" decls need to be defined in the same 2231 translation unit, we can make the type internal. */ 2232 constrain_visibility (decl, VISIBILITY_ANON, false); 2233 2234 /* If visibility changed and DECL already has DECL_RTL, ensure 2235 symbol flags are updated. */ 2236 if ((DECL_VISIBILITY (decl) != orig_visibility 2237 || DECL_VISIBILITY_SPECIFIED (decl) != orig_visibility_specified) 2238 && ((TREE_CODE (decl) == VAR_DECL && TREE_STATIC (decl)) 2239 || TREE_CODE (decl) == FUNCTION_DECL) 2240 && DECL_RTL_SET_P (decl)) 2241 make_decl_rtl (decl); 2242 } 2243 2244 /* By default, static data members and function members receive 2245 the visibility of their containing class. */ 2246 2247 static void 2248 determine_visibility_from_class (tree decl, tree class_type) 2249 { 2250 if (DECL_VISIBILITY_SPECIFIED (decl)) 2251 return; 2252 2253 if (determine_hidden_inline (decl)) 2254 DECL_VISIBILITY (decl) = VISIBILITY_HIDDEN; 2255 else 2256 { 2257 /* Default to the class visibility. */ 2258 DECL_VISIBILITY (decl) = CLASSTYPE_VISIBILITY (class_type); 2259 DECL_VISIBILITY_SPECIFIED (decl) 2260 = CLASSTYPE_VISIBILITY_SPECIFIED (class_type); 2261 } 2262 2263 /* Give the target a chance to override the visibility associated 2264 with DECL. */ 2265 if (TREE_CODE (decl) == VAR_DECL 2266 && (DECL_TINFO_P (decl) 2267 || (DECL_VTABLE_OR_VTT_P (decl) 2268 /* Construction virtual tables are not exported because 2269 they cannot be referred to from other object files; 2270 their name is not standardized by the ABI. */ 2271 && !DECL_CONSTRUCTION_VTABLE_P (decl))) 2272 && TREE_PUBLIC (decl) 2273 && !DECL_REALLY_EXTERN (decl) 2274 && !CLASSTYPE_VISIBILITY_SPECIFIED (class_type)) 2275 targetm.cxx.determine_class_data_visibility (decl); 2276 } 2277 2278 /* Returns true iff DECL is an inline that should get hidden visibility 2279 because of -fvisibility-inlines-hidden. */ 2280 2281 static bool 2282 determine_hidden_inline (tree decl) 2283 { 2284 return (visibility_options.inlines_hidden 2285 /* Don't do this for inline templates; specializations might not be 2286 inline, and we don't want them to inherit the hidden 2287 visibility. We'll set it here for all inline instantiations. */ 2288 && !processing_template_decl 2289 && TREE_CODE (decl) == FUNCTION_DECL 2290 && DECL_DECLARED_INLINE_P (decl) 2291 && (! DECL_LANG_SPECIFIC (decl) 2292 || ! DECL_EXPLICIT_INSTANTIATION (decl))); 2293 } 2294 2295 /* Constrain the visibility of a class TYPE based on the visibility of its 2296 field types. Warn if any fields require lesser visibility. */ 2297 2298 void 2299 constrain_class_visibility (tree type) 2300 { 2301 tree binfo; 2302 tree t; 2303 int i; 2304 2305 int vis = type_visibility (type); 2306 2307 if (vis == VISIBILITY_ANON 2308 || DECL_IN_SYSTEM_HEADER (TYPE_MAIN_DECL (type))) 2309 return; 2310 2311 /* Don't warn about visibility if the class has explicit visibility. */ 2312 if (CLASSTYPE_VISIBILITY_SPECIFIED (type)) 2313 vis = VISIBILITY_INTERNAL; 2314 2315 for (t = TYPE_FIELDS (type); t; t = DECL_CHAIN (t)) 2316 if (TREE_CODE (t) == FIELD_DECL && TREE_TYPE (t) != error_mark_node) 2317 { 2318 tree ftype = strip_pointer_or_array_types (TREE_TYPE (t)); 2319 int subvis = type_visibility (ftype); 2320 2321 if (subvis == VISIBILITY_ANON) 2322 { 2323 if (!in_main_input_context ()) 2324 warning (0, "\ 2325 %qT has a field %qD whose type uses the anonymous namespace", 2326 type, t); 2327 } 2328 else if (MAYBE_CLASS_TYPE_P (ftype) 2329 && vis < VISIBILITY_HIDDEN 2330 && subvis >= VISIBILITY_HIDDEN) 2331 warning (OPT_Wattributes, "\ 2332 %qT declared with greater visibility than the type of its field %qD", 2333 type, t); 2334 } 2335 2336 binfo = TYPE_BINFO (type); 2337 for (i = 0; BINFO_BASE_ITERATE (binfo, i, t); ++i) 2338 { 2339 int subvis = type_visibility (TREE_TYPE (t)); 2340 2341 if (subvis == VISIBILITY_ANON) 2342 { 2343 if (!in_main_input_context()) 2344 warning (0, "\ 2345 %qT has a base %qT whose type uses the anonymous namespace", 2346 type, TREE_TYPE (t)); 2347 } 2348 else if (vis < VISIBILITY_HIDDEN 2349 && subvis >= VISIBILITY_HIDDEN) 2350 warning (OPT_Wattributes, "\ 2351 %qT declared with greater visibility than its base %qT", 2352 type, TREE_TYPE (t)); 2353 } 2354 } 2355 2356 /* DECL is a FUNCTION_DECL or VAR_DECL. If the object file linkage 2357 for DECL has not already been determined, do so now by setting 2358 DECL_EXTERNAL, DECL_COMDAT and other related flags. Until this 2359 function is called entities with vague linkage whose definitions 2360 are available must have TREE_PUBLIC set. 2361 2362 If this function decides to place DECL in COMDAT, it will set 2363 appropriate flags -- but will not clear DECL_EXTERNAL. It is up to 2364 the caller to decide whether or not to clear DECL_EXTERNAL. Some 2365 callers defer that decision until it is clear that DECL is actually 2366 required. */ 2367 2368 void 2369 import_export_decl (tree decl) 2370 { 2371 int emit_p; 2372 bool comdat_p; 2373 bool import_p; 2374 tree class_type = NULL_TREE; 2375 2376 if (DECL_INTERFACE_KNOWN (decl)) 2377 return; 2378 2379 /* We cannot determine what linkage to give to an entity with vague 2380 linkage until the end of the file. For example, a virtual table 2381 for a class will be defined if and only if the key method is 2382 defined in this translation unit. As a further example, consider 2383 that when compiling a translation unit that uses PCH file with 2384 "-frepo" it would be incorrect to make decisions about what 2385 entities to emit when building the PCH; those decisions must be 2386 delayed until the repository information has been processed. */ 2387 gcc_assert (at_eof); 2388 /* Object file linkage for explicit instantiations is handled in 2389 mark_decl_instantiated. For static variables in functions with 2390 vague linkage, maybe_commonize_var is used. 2391 2392 Therefore, the only declarations that should be provided to this 2393 function are those with external linkage that are: 2394 2395 * implicit instantiations of function templates 2396 2397 * inline function 2398 2399 * implicit instantiations of static data members of class 2400 templates 2401 2402 * virtual tables 2403 2404 * typeinfo objects 2405 2406 Furthermore, all entities that reach this point must have a 2407 definition available in this translation unit. 2408 2409 The following assertions check these conditions. */ 2410 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL 2411 || TREE_CODE (decl) == VAR_DECL); 2412 /* Any code that creates entities with TREE_PUBLIC cleared should 2413 also set DECL_INTERFACE_KNOWN. */ 2414 gcc_assert (TREE_PUBLIC (decl)); 2415 if (TREE_CODE (decl) == FUNCTION_DECL) 2416 gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl) 2417 || DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl) 2418 || DECL_DECLARED_INLINE_P (decl)); 2419 else 2420 gcc_assert (DECL_IMPLICIT_INSTANTIATION (decl) 2421 || DECL_VTABLE_OR_VTT_P (decl) 2422 || DECL_TINFO_P (decl)); 2423 /* Check that a definition of DECL is available in this translation 2424 unit. */ 2425 gcc_assert (!DECL_REALLY_EXTERN (decl)); 2426 2427 /* Assume that DECL will not have COMDAT linkage. */ 2428 comdat_p = false; 2429 /* Assume that DECL will not be imported into this translation 2430 unit. */ 2431 import_p = false; 2432 2433 /* See if the repository tells us whether or not to emit DECL in 2434 this translation unit. */ 2435 emit_p = repo_emit_p (decl); 2436 if (emit_p == 0) 2437 import_p = true; 2438 else if (emit_p == 1) 2439 { 2440 /* The repository indicates that this entity should be defined 2441 here. Make sure the back end honors that request. */ 2442 if (TREE_CODE (decl) == VAR_DECL) 2443 mark_needed (decl); 2444 else if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl) 2445 || DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (decl)) 2446 { 2447 tree clone; 2448 FOR_EACH_CLONE (clone, decl) 2449 mark_needed (clone); 2450 } 2451 else 2452 mark_needed (decl); 2453 /* Output the definition as an ordinary strong definition. */ 2454 DECL_EXTERNAL (decl) = 0; 2455 DECL_INTERFACE_KNOWN (decl) = 1; 2456 return; 2457 } 2458 2459 if (import_p) 2460 /* We have already decided what to do with this DECL; there is no 2461 need to check anything further. */ 2462 ; 2463 else if (TREE_CODE (decl) == VAR_DECL && DECL_VTABLE_OR_VTT_P (decl)) 2464 { 2465 class_type = DECL_CONTEXT (decl); 2466 import_export_class (class_type); 2467 if (TYPE_FOR_JAVA (class_type)) 2468 import_p = true; 2469 else if (CLASSTYPE_INTERFACE_KNOWN (class_type) 2470 && CLASSTYPE_INTERFACE_ONLY (class_type)) 2471 import_p = true; 2472 else if ((!flag_weak || TARGET_WEAK_NOT_IN_ARCHIVE_TOC) 2473 && !CLASSTYPE_USE_TEMPLATE (class_type) 2474 && CLASSTYPE_KEY_METHOD (class_type) 2475 && !DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type))) 2476 /* The ABI requires that all virtual tables be emitted with 2477 COMDAT linkage. However, on systems where COMDAT symbols 2478 don't show up in the table of contents for a static 2479 archive, or on systems without weak symbols (where we 2480 approximate COMDAT linkage by using internal linkage), the 2481 linker will report errors about undefined symbols because 2482 it will not see the virtual table definition. Therefore, 2483 in the case that we know that the virtual table will be 2484 emitted in only one translation unit, we make the virtual 2485 table an ordinary definition with external linkage. */ 2486 DECL_EXTERNAL (decl) = 0; 2487 else if (CLASSTYPE_INTERFACE_KNOWN (class_type)) 2488 { 2489 /* CLASS_TYPE is being exported from this translation unit, 2490 so DECL should be defined here. */ 2491 if (!flag_weak && CLASSTYPE_EXPLICIT_INSTANTIATION (class_type)) 2492 /* If a class is declared in a header with the "extern 2493 template" extension, then it will not be instantiated, 2494 even in translation units that would normally require 2495 it. Often such classes are explicitly instantiated in 2496 one translation unit. Therefore, the explicit 2497 instantiation must be made visible to other translation 2498 units. */ 2499 DECL_EXTERNAL (decl) = 0; 2500 else 2501 { 2502 /* The generic C++ ABI says that class data is always 2503 COMDAT, even if there is a key function. Some 2504 variants (e.g., the ARM EABI) says that class data 2505 only has COMDAT linkage if the class data might be 2506 emitted in more than one translation unit. When the 2507 key method can be inline and is inline, we still have 2508 to arrange for comdat even though 2509 class_data_always_comdat is false. */ 2510 if (!CLASSTYPE_KEY_METHOD (class_type) 2511 || DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (class_type)) 2512 || targetm.cxx.class_data_always_comdat ()) 2513 { 2514 /* The ABI requires COMDAT linkage. Normally, we 2515 only emit COMDAT things when they are needed; 2516 make sure that we realize that this entity is 2517 indeed needed. */ 2518 comdat_p = true; 2519 mark_needed (decl); 2520 } 2521 } 2522 } 2523 else if (!flag_implicit_templates 2524 && CLASSTYPE_IMPLICIT_INSTANTIATION (class_type)) 2525 import_p = true; 2526 else 2527 comdat_p = true; 2528 } 2529 else if (TREE_CODE (decl) == VAR_DECL && DECL_TINFO_P (decl)) 2530 { 2531 tree type = TREE_TYPE (DECL_NAME (decl)); 2532 if (CLASS_TYPE_P (type)) 2533 { 2534 class_type = type; 2535 import_export_class (type); 2536 if (CLASSTYPE_INTERFACE_KNOWN (type) 2537 && TYPE_POLYMORPHIC_P (type) 2538 && CLASSTYPE_INTERFACE_ONLY (type) 2539 /* If -fno-rtti was specified, then we cannot be sure 2540 that RTTI information will be emitted with the 2541 virtual table of the class, so we must emit it 2542 wherever it is used. */ 2543 && flag_rtti) 2544 import_p = true; 2545 else 2546 { 2547 if (CLASSTYPE_INTERFACE_KNOWN (type) 2548 && !CLASSTYPE_INTERFACE_ONLY (type)) 2549 { 2550 comdat_p = (targetm.cxx.class_data_always_comdat () 2551 || (CLASSTYPE_KEY_METHOD (type) 2552 && DECL_DECLARED_INLINE_P (CLASSTYPE_KEY_METHOD (type)))); 2553 mark_needed (decl); 2554 if (!flag_weak) 2555 { 2556 comdat_p = false; 2557 DECL_EXTERNAL (decl) = 0; 2558 } 2559 } 2560 else 2561 comdat_p = true; 2562 } 2563 } 2564 else 2565 comdat_p = true; 2566 } 2567 else if (DECL_TEMPLATE_INSTANTIATION (decl) 2568 || DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)) 2569 { 2570 /* DECL is an implicit instantiation of a function or static 2571 data member. */ 2572 if ((flag_implicit_templates 2573 && !flag_use_repository) 2574 || (flag_implicit_inline_templates 2575 && TREE_CODE (decl) == FUNCTION_DECL 2576 && DECL_DECLARED_INLINE_P (decl))) 2577 comdat_p = true; 2578 else 2579 /* If we are not implicitly generating templates, then mark 2580 this entity as undefined in this translation unit. */ 2581 import_p = true; 2582 } 2583 else if (DECL_FUNCTION_MEMBER_P (decl)) 2584 { 2585 if (!DECL_DECLARED_INLINE_P (decl)) 2586 { 2587 tree ctype = DECL_CONTEXT (decl); 2588 import_export_class (ctype); 2589 if (CLASSTYPE_INTERFACE_KNOWN (ctype)) 2590 { 2591 DECL_NOT_REALLY_EXTERN (decl) 2592 = ! (CLASSTYPE_INTERFACE_ONLY (ctype) 2593 || (DECL_DECLARED_INLINE_P (decl) 2594 && ! flag_implement_inlines 2595 && !DECL_VINDEX (decl))); 2596 2597 if (!DECL_NOT_REALLY_EXTERN (decl)) 2598 DECL_EXTERNAL (decl) = 1; 2599 2600 /* Always make artificials weak. */ 2601 if (DECL_ARTIFICIAL (decl) && flag_weak) 2602 comdat_p = true; 2603 else 2604 maybe_make_one_only (decl); 2605 } 2606 } 2607 else 2608 comdat_p = true; 2609 } 2610 else 2611 comdat_p = true; 2612 2613 if (import_p) 2614 { 2615 /* If we are importing DECL into this translation unit, mark is 2616 an undefined here. */ 2617 DECL_EXTERNAL (decl) = 1; 2618 DECL_NOT_REALLY_EXTERN (decl) = 0; 2619 } 2620 else if (comdat_p) 2621 { 2622 /* If we decided to put DECL in COMDAT, mark it accordingly at 2623 this point. */ 2624 comdat_linkage (decl); 2625 } 2626 2627 DECL_INTERFACE_KNOWN (decl) = 1; 2628 } 2629 2630 /* Return an expression that performs the destruction of DECL, which 2631 must be a VAR_DECL whose type has a non-trivial destructor, or is 2632 an array whose (innermost) elements have a non-trivial destructor. */ 2633 2634 tree 2635 build_cleanup (tree decl) 2636 { 2637 tree temp; 2638 tree type = TREE_TYPE (decl); 2639 2640 /* This function should only be called for declarations that really 2641 require cleanups. */ 2642 gcc_assert (!TYPE_HAS_TRIVIAL_DESTRUCTOR (type)); 2643 2644 /* Treat all objects with destructors as used; the destructor may do 2645 something substantive. */ 2646 mark_used (decl); 2647 2648 if (TREE_CODE (type) == ARRAY_TYPE) 2649 temp = decl; 2650 else 2651 temp = build_address (decl); 2652 temp = build_delete (TREE_TYPE (temp), temp, 2653 sfk_complete_destructor, 2654 LOOKUP_NORMAL|LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR, 0, 2655 tf_warning_or_error); 2656 return temp; 2657 } 2658 2659 /* Returns the initialization guard variable for the variable DECL, 2660 which has static storage duration. */ 2661 2662 tree 2663 get_guard (tree decl) 2664 { 2665 tree sname; 2666 tree guard; 2667 2668 sname = mangle_guard_variable (decl); 2669 guard = IDENTIFIER_GLOBAL_VALUE (sname); 2670 if (! guard) 2671 { 2672 tree guard_type; 2673 2674 /* We use a type that is big enough to contain a mutex as well 2675 as an integer counter. */ 2676 guard_type = targetm.cxx.guard_type (); 2677 guard = build_decl (DECL_SOURCE_LOCATION (decl), 2678 VAR_DECL, sname, guard_type); 2679 2680 /* The guard should have the same linkage as what it guards. */ 2681 TREE_PUBLIC (guard) = TREE_PUBLIC (decl); 2682 TREE_STATIC (guard) = TREE_STATIC (decl); 2683 DECL_COMMON (guard) = DECL_COMMON (decl); 2684 DECL_COMDAT (guard) = DECL_COMDAT (decl); 2685 if (DECL_ONE_ONLY (decl)) 2686 make_decl_one_only (guard, cxx_comdat_group (guard)); 2687 if (TREE_PUBLIC (decl)) 2688 DECL_WEAK (guard) = DECL_WEAK (decl); 2689 DECL_VISIBILITY (guard) = DECL_VISIBILITY (decl); 2690 DECL_VISIBILITY_SPECIFIED (guard) = DECL_VISIBILITY_SPECIFIED (decl); 2691 2692 DECL_ARTIFICIAL (guard) = 1; 2693 DECL_IGNORED_P (guard) = 1; 2694 TREE_USED (guard) = 1; 2695 pushdecl_top_level_and_finish (guard, NULL_TREE); 2696 } 2697 return guard; 2698 } 2699 2700 /* Return those bits of the GUARD variable that should be set when the 2701 guarded entity is actually initialized. */ 2702 2703 static tree 2704 get_guard_bits (tree guard) 2705 { 2706 if (!targetm.cxx.guard_mask_bit ()) 2707 { 2708 /* We only set the first byte of the guard, in order to leave room 2709 for a mutex in the high-order bits. */ 2710 guard = build1 (ADDR_EXPR, 2711 build_pointer_type (TREE_TYPE (guard)), 2712 guard); 2713 guard = build1 (NOP_EXPR, 2714 build_pointer_type (char_type_node), 2715 guard); 2716 guard = build1 (INDIRECT_REF, char_type_node, guard); 2717 } 2718 2719 return guard; 2720 } 2721 2722 /* Return an expression which determines whether or not the GUARD 2723 variable has already been initialized. */ 2724 2725 tree 2726 get_guard_cond (tree guard) 2727 { 2728 tree guard_value; 2729 2730 /* Check to see if the GUARD is zero. */ 2731 guard = get_guard_bits (guard); 2732 2733 /* Mask off all but the low bit. */ 2734 if (targetm.cxx.guard_mask_bit ()) 2735 { 2736 guard_value = integer_one_node; 2737 if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard))) 2738 guard_value = convert (TREE_TYPE (guard), guard_value); 2739 guard = cp_build_binary_op (input_location, 2740 BIT_AND_EXPR, guard, guard_value, 2741 tf_warning_or_error); 2742 } 2743 2744 guard_value = integer_zero_node; 2745 if (!same_type_p (TREE_TYPE (guard_value), TREE_TYPE (guard))) 2746 guard_value = convert (TREE_TYPE (guard), guard_value); 2747 return cp_build_binary_op (input_location, 2748 EQ_EXPR, guard, guard_value, 2749 tf_warning_or_error); 2750 } 2751 2752 /* Return an expression which sets the GUARD variable, indicating that 2753 the variable being guarded has been initialized. */ 2754 2755 tree 2756 set_guard (tree guard) 2757 { 2758 tree guard_init; 2759 2760 /* Set the GUARD to one. */ 2761 guard = get_guard_bits (guard); 2762 guard_init = integer_one_node; 2763 if (!same_type_p (TREE_TYPE (guard_init), TREE_TYPE (guard))) 2764 guard_init = convert (TREE_TYPE (guard), guard_init); 2765 return cp_build_modify_expr (guard, NOP_EXPR, guard_init, 2766 tf_warning_or_error); 2767 } 2768 2769 /* Start the process of running a particular set of global constructors 2770 or destructors. Subroutine of do_[cd]tors. */ 2771 2772 static tree 2773 start_objects (int method_type, int initp) 2774 { 2775 tree body; 2776 tree fndecl; 2777 char type[14]; 2778 2779 /* Make ctor or dtor function. METHOD_TYPE may be 'I' or 'D'. */ 2780 2781 if (initp != DEFAULT_INIT_PRIORITY) 2782 { 2783 char joiner; 2784 2785 #ifdef JOINER 2786 joiner = JOINER; 2787 #else 2788 joiner = '_'; 2789 #endif 2790 2791 sprintf (type, "sub_%c%c%.5u", method_type, joiner, initp); 2792 } 2793 else 2794 sprintf (type, "sub_%c", method_type); 2795 2796 fndecl = build_lang_decl (FUNCTION_DECL, 2797 get_file_function_name (type), 2798 build_function_type_list (void_type_node, 2799 NULL_TREE)); 2800 start_preparsed_function (fndecl, /*attrs=*/NULL_TREE, SF_PRE_PARSED); 2801 2802 TREE_PUBLIC (current_function_decl) = 0; 2803 2804 /* Mark as artificial because it's not explicitly in the user's 2805 source code. */ 2806 DECL_ARTIFICIAL (current_function_decl) = 1; 2807 2808 /* Mark this declaration as used to avoid spurious warnings. */ 2809 TREE_USED (current_function_decl) = 1; 2810 2811 /* Mark this function as a global constructor or destructor. */ 2812 if (method_type == 'I') 2813 DECL_GLOBAL_CTOR_P (current_function_decl) = 1; 2814 else 2815 DECL_GLOBAL_DTOR_P (current_function_decl) = 1; 2816 2817 body = begin_compound_stmt (BCS_FN_BODY); 2818 2819 return body; 2820 } 2821 2822 /* Finish the process of running a particular set of global constructors 2823 or destructors. Subroutine of do_[cd]tors. */ 2824 2825 static void 2826 finish_objects (int method_type, int initp, tree body) 2827 { 2828 tree fn; 2829 2830 /* Finish up. */ 2831 finish_compound_stmt (body); 2832 fn = finish_function (0); 2833 2834 if (method_type == 'I') 2835 { 2836 DECL_STATIC_CONSTRUCTOR (fn) = 1; 2837 decl_init_priority_insert (fn, initp); 2838 } 2839 else 2840 { 2841 DECL_STATIC_DESTRUCTOR (fn) = 1; 2842 decl_fini_priority_insert (fn, initp); 2843 } 2844 2845 expand_or_defer_fn (fn); 2846 } 2847 2848 /* The names of the parameters to the function created to handle 2849 initializations and destructions for objects with static storage 2850 duration. */ 2851 #define INITIALIZE_P_IDENTIFIER "__initialize_p" 2852 #define PRIORITY_IDENTIFIER "__priority" 2853 2854 /* The name of the function we create to handle initializations and 2855 destructions for objects with static storage duration. */ 2856 #define SSDF_IDENTIFIER "__static_initialization_and_destruction" 2857 2858 /* The declaration for the __INITIALIZE_P argument. */ 2859 static GTY(()) tree initialize_p_decl; 2860 2861 /* The declaration for the __PRIORITY argument. */ 2862 static GTY(()) tree priority_decl; 2863 2864 /* The declaration for the static storage duration function. */ 2865 static GTY(()) tree ssdf_decl; 2866 2867 /* All the static storage duration functions created in this 2868 translation unit. */ 2869 static GTY(()) VEC(tree,gc) *ssdf_decls; 2870 2871 /* A map from priority levels to information about that priority 2872 level. There may be many such levels, so efficient lookup is 2873 important. */ 2874 static splay_tree priority_info_map; 2875 2876 /* Begins the generation of the function that will handle all 2877 initialization and destruction of objects with static storage 2878 duration. The function generated takes two parameters of type 2879 `int': __INITIALIZE_P and __PRIORITY. If __INITIALIZE_P is 2880 nonzero, it performs initializations. Otherwise, it performs 2881 destructions. It only performs those initializations or 2882 destructions with the indicated __PRIORITY. The generated function 2883 returns no value. 2884 2885 It is assumed that this function will only be called once per 2886 translation unit. */ 2887 2888 static tree 2889 start_static_storage_duration_function (unsigned count) 2890 { 2891 tree type; 2892 tree body; 2893 char id[sizeof (SSDF_IDENTIFIER) + 1 /* '\0' */ + 32]; 2894 2895 /* Create the identifier for this function. It will be of the form 2896 SSDF_IDENTIFIER_<number>. */ 2897 sprintf (id, "%s_%u", SSDF_IDENTIFIER, count); 2898 2899 type = build_function_type_list (void_type_node, 2900 integer_type_node, integer_type_node, 2901 NULL_TREE); 2902 2903 /* Create the FUNCTION_DECL itself. */ 2904 ssdf_decl = build_lang_decl (FUNCTION_DECL, 2905 get_identifier (id), 2906 type); 2907 TREE_PUBLIC (ssdf_decl) = 0; 2908 DECL_ARTIFICIAL (ssdf_decl) = 1; 2909 2910 /* Put this function in the list of functions to be called from the 2911 static constructors and destructors. */ 2912 if (!ssdf_decls) 2913 { 2914 ssdf_decls = VEC_alloc (tree, gc, 32); 2915 2916 /* Take this opportunity to initialize the map from priority 2917 numbers to information about that priority level. */ 2918 priority_info_map = splay_tree_new (splay_tree_compare_ints, 2919 /*delete_key_fn=*/0, 2920 /*delete_value_fn=*/ 2921 (splay_tree_delete_value_fn) &free); 2922 2923 /* We always need to generate functions for the 2924 DEFAULT_INIT_PRIORITY so enter it now. That way when we walk 2925 priorities later, we'll be sure to find the 2926 DEFAULT_INIT_PRIORITY. */ 2927 get_priority_info (DEFAULT_INIT_PRIORITY); 2928 } 2929 2930 VEC_safe_push (tree, gc, ssdf_decls, ssdf_decl); 2931 2932 /* Create the argument list. */ 2933 initialize_p_decl = cp_build_parm_decl 2934 (get_identifier (INITIALIZE_P_IDENTIFIER), integer_type_node); 2935 DECL_CONTEXT (initialize_p_decl) = ssdf_decl; 2936 TREE_USED (initialize_p_decl) = 1; 2937 priority_decl = cp_build_parm_decl 2938 (get_identifier (PRIORITY_IDENTIFIER), integer_type_node); 2939 DECL_CONTEXT (priority_decl) = ssdf_decl; 2940 TREE_USED (priority_decl) = 1; 2941 2942 DECL_CHAIN (initialize_p_decl) = priority_decl; 2943 DECL_ARGUMENTS (ssdf_decl) = initialize_p_decl; 2944 2945 /* Put the function in the global scope. */ 2946 pushdecl (ssdf_decl); 2947 2948 /* Start the function itself. This is equivalent to declaring the 2949 function as: 2950 2951 static void __ssdf (int __initialize_p, init __priority_p); 2952 2953 It is static because we only need to call this function from the 2954 various constructor and destructor functions for this module. */ 2955 start_preparsed_function (ssdf_decl, 2956 /*attrs=*/NULL_TREE, 2957 SF_PRE_PARSED); 2958 2959 /* Set up the scope of the outermost block in the function. */ 2960 body = begin_compound_stmt (BCS_FN_BODY); 2961 2962 return body; 2963 } 2964 2965 /* Finish the generation of the function which performs initialization 2966 and destruction of objects with static storage duration. After 2967 this point, no more such objects can be created. */ 2968 2969 static void 2970 finish_static_storage_duration_function (tree body) 2971 { 2972 /* Close out the function. */ 2973 finish_compound_stmt (body); 2974 expand_or_defer_fn (finish_function (0)); 2975 } 2976 2977 /* Return the information about the indicated PRIORITY level. If no 2978 code to handle this level has yet been generated, generate the 2979 appropriate prologue. */ 2980 2981 static priority_info 2982 get_priority_info (int priority) 2983 { 2984 priority_info pi; 2985 splay_tree_node n; 2986 2987 n = splay_tree_lookup (priority_info_map, 2988 (splay_tree_key) priority); 2989 if (!n) 2990 { 2991 /* Create a new priority information structure, and insert it 2992 into the map. */ 2993 pi = XNEW (struct priority_info_s); 2994 pi->initializations_p = 0; 2995 pi->destructions_p = 0; 2996 splay_tree_insert (priority_info_map, 2997 (splay_tree_key) priority, 2998 (splay_tree_value) pi); 2999 } 3000 else 3001 pi = (priority_info) n->value; 3002 3003 return pi; 3004 } 3005 3006 /* The effective initialization priority of a DECL. */ 3007 3008 #define DECL_EFFECTIVE_INIT_PRIORITY(decl) \ 3009 ((!DECL_HAS_INIT_PRIORITY_P (decl) || DECL_INIT_PRIORITY (decl) == 0) \ 3010 ? DEFAULT_INIT_PRIORITY : DECL_INIT_PRIORITY (decl)) 3011 3012 /* Whether a DECL needs a guard to protect it against multiple 3013 initialization. */ 3014 3015 #define NEEDS_GUARD_P(decl) (TREE_PUBLIC (decl) && (DECL_COMMON (decl) \ 3016 || DECL_ONE_ONLY (decl) \ 3017 || DECL_WEAK (decl))) 3018 3019 /* Called from one_static_initialization_or_destruction(), 3020 via walk_tree. 3021 Walks the initializer list of a global variable and looks for 3022 temporary variables (DECL_NAME() == NULL and DECL_ARTIFICIAL != 0) 3023 and that have their DECL_CONTEXT() == NULL. 3024 For each such temporary variable, set their DECL_CONTEXT() to 3025 the current function. This is necessary because otherwise 3026 some optimizers (enabled by -O2 -fprofile-arcs) might crash 3027 when trying to refer to a temporary variable that does not have 3028 it's DECL_CONTECT() properly set. */ 3029 static tree 3030 fix_temporary_vars_context_r (tree *node, 3031 int *unused ATTRIBUTE_UNUSED, 3032 void *unused1 ATTRIBUTE_UNUSED) 3033 { 3034 gcc_assert (current_function_decl); 3035 3036 if (TREE_CODE (*node) == BIND_EXPR) 3037 { 3038 tree var; 3039 3040 for (var = BIND_EXPR_VARS (*node); var; var = DECL_CHAIN (var)) 3041 if (TREE_CODE (var) == VAR_DECL 3042 && !DECL_NAME (var) 3043 && DECL_ARTIFICIAL (var) 3044 && !DECL_CONTEXT (var)) 3045 DECL_CONTEXT (var) = current_function_decl; 3046 } 3047 3048 return NULL_TREE; 3049 } 3050 3051 /* Set up to handle the initialization or destruction of DECL. If 3052 INITP is nonzero, we are initializing the variable. Otherwise, we 3053 are destroying it. */ 3054 3055 static void 3056 one_static_initialization_or_destruction (tree decl, tree init, bool initp) 3057 { 3058 tree guard_if_stmt = NULL_TREE; 3059 tree guard; 3060 3061 /* If we are supposed to destruct and there's a trivial destructor, 3062 nothing has to be done. */ 3063 if (!initp 3064 && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl))) 3065 return; 3066 3067 /* Trick the compiler into thinking we are at the file and line 3068 where DECL was declared so that error-messages make sense, and so 3069 that the debugger will show somewhat sensible file and line 3070 information. */ 3071 input_location = DECL_SOURCE_LOCATION (decl); 3072 3073 /* Make sure temporary variables in the initialiser all have 3074 their DECL_CONTEXT() set to a value different from NULL_TREE. 3075 This can happen when global variables initialisers are built. 3076 In that case, the DECL_CONTEXT() of the global variables _AND_ of all 3077 the temporary variables that might have been generated in the 3078 accompagning initialisers is NULL_TREE, meaning the variables have been 3079 declared in the global namespace. 3080 What we want to do here is to fix that and make sure the DECL_CONTEXT() 3081 of the temporaries are set to the current function decl. */ 3082 cp_walk_tree_without_duplicates (&init, 3083 fix_temporary_vars_context_r, 3084 NULL); 3085 3086 /* Because of: 3087 3088 [class.access.spec] 3089 3090 Access control for implicit calls to the constructors, 3091 the conversion functions, or the destructor called to 3092 create and destroy a static data member is performed as 3093 if these calls appeared in the scope of the member's 3094 class. 3095 3096 we pretend we are in a static member function of the class of 3097 which the DECL is a member. */ 3098 if (member_p (decl)) 3099 { 3100 DECL_CONTEXT (current_function_decl) = DECL_CONTEXT (decl); 3101 DECL_STATIC_FUNCTION_P (current_function_decl) = 1; 3102 } 3103 3104 /* Assume we don't need a guard. */ 3105 guard = NULL_TREE; 3106 /* We need a guard if this is an object with external linkage that 3107 might be initialized in more than one place. (For example, a 3108 static data member of a template, when the data member requires 3109 construction.) */ 3110 if (NEEDS_GUARD_P (decl)) 3111 { 3112 tree guard_cond; 3113 3114 guard = get_guard (decl); 3115 3116 /* When using __cxa_atexit, we just check the GUARD as we would 3117 for a local static. */ 3118 if (flag_use_cxa_atexit) 3119 { 3120 /* When using __cxa_atexit, we never try to destroy 3121 anything from a static destructor. */ 3122 gcc_assert (initp); 3123 guard_cond = get_guard_cond (guard); 3124 } 3125 /* If we don't have __cxa_atexit, then we will be running 3126 destructors from .fini sections, or their equivalents. So, 3127 we need to know how many times we've tried to initialize this 3128 object. We do initializations only if the GUARD is zero, 3129 i.e., if we are the first to initialize the variable. We do 3130 destructions only if the GUARD is one, i.e., if we are the 3131 last to destroy the variable. */ 3132 else if (initp) 3133 guard_cond 3134 = cp_build_binary_op (input_location, 3135 EQ_EXPR, 3136 cp_build_unary_op (PREINCREMENT_EXPR, 3137 guard, 3138 /*noconvert=*/1, 3139 tf_warning_or_error), 3140 integer_one_node, 3141 tf_warning_or_error); 3142 else 3143 guard_cond 3144 = cp_build_binary_op (input_location, 3145 EQ_EXPR, 3146 cp_build_unary_op (PREDECREMENT_EXPR, 3147 guard, 3148 /*noconvert=*/1, 3149 tf_warning_or_error), 3150 integer_zero_node, 3151 tf_warning_or_error); 3152 3153 guard_if_stmt = begin_if_stmt (); 3154 finish_if_stmt_cond (guard_cond, guard_if_stmt); 3155 } 3156 3157 3158 /* If we're using __cxa_atexit, we have not already set the GUARD, 3159 so we must do so now. */ 3160 if (guard && initp && flag_use_cxa_atexit) 3161 finish_expr_stmt (set_guard (guard)); 3162 3163 /* Perform the initialization or destruction. */ 3164 if (initp) 3165 { 3166 if (init) 3167 finish_expr_stmt (init); 3168 3169 /* If we're using __cxa_atexit, register a function that calls the 3170 destructor for the object. */ 3171 if (flag_use_cxa_atexit) 3172 finish_expr_stmt (register_dtor_fn (decl)); 3173 } 3174 else 3175 finish_expr_stmt (build_cleanup (decl)); 3176 3177 /* Finish the guard if-stmt, if necessary. */ 3178 if (guard) 3179 { 3180 finish_then_clause (guard_if_stmt); 3181 finish_if_stmt (guard_if_stmt); 3182 } 3183 3184 /* Now that we're done with DECL we don't need to pretend to be a 3185 member of its class any longer. */ 3186 DECL_CONTEXT (current_function_decl) = NULL_TREE; 3187 DECL_STATIC_FUNCTION_P (current_function_decl) = 0; 3188 } 3189 3190 /* Generate code to do the initialization or destruction of the decls in VARS, 3191 a TREE_LIST of VAR_DECL with static storage duration. 3192 Whether initialization or destruction is performed is specified by INITP. */ 3193 3194 static void 3195 do_static_initialization_or_destruction (tree vars, bool initp) 3196 { 3197 tree node, init_if_stmt, cond; 3198 3199 /* Build the outer if-stmt to check for initialization or destruction. */ 3200 init_if_stmt = begin_if_stmt (); 3201 cond = initp ? integer_one_node : integer_zero_node; 3202 cond = cp_build_binary_op (input_location, 3203 EQ_EXPR, 3204 initialize_p_decl, 3205 cond, 3206 tf_warning_or_error); 3207 finish_if_stmt_cond (cond, init_if_stmt); 3208 3209 node = vars; 3210 do { 3211 tree decl = TREE_VALUE (node); 3212 tree priority_if_stmt; 3213 int priority; 3214 priority_info pi; 3215 3216 /* If we don't need a destructor, there's nothing to do. Avoid 3217 creating a possibly empty if-stmt. */ 3218 if (!initp && TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl))) 3219 { 3220 node = TREE_CHAIN (node); 3221 continue; 3222 } 3223 3224 /* Remember that we had an initialization or finalization at this 3225 priority. */ 3226 priority = DECL_EFFECTIVE_INIT_PRIORITY (decl); 3227 pi = get_priority_info (priority); 3228 if (initp) 3229 pi->initializations_p = 1; 3230 else 3231 pi->destructions_p = 1; 3232 3233 /* Conditionalize this initialization on being in the right priority 3234 and being initializing/finalizing appropriately. */ 3235 priority_if_stmt = begin_if_stmt (); 3236 cond = cp_build_binary_op (input_location, 3237 EQ_EXPR, 3238 priority_decl, 3239 build_int_cst (NULL_TREE, priority), 3240 tf_warning_or_error); 3241 finish_if_stmt_cond (cond, priority_if_stmt); 3242 3243 /* Process initializers with same priority. */ 3244 for (; node 3245 && DECL_EFFECTIVE_INIT_PRIORITY (TREE_VALUE (node)) == priority; 3246 node = TREE_CHAIN (node)) 3247 /* Do one initialization or destruction. */ 3248 one_static_initialization_or_destruction (TREE_VALUE (node), 3249 TREE_PURPOSE (node), initp); 3250 3251 /* Finish up the priority if-stmt body. */ 3252 finish_then_clause (priority_if_stmt); 3253 finish_if_stmt (priority_if_stmt); 3254 3255 } while (node); 3256 3257 /* Finish up the init/destruct if-stmt body. */ 3258 finish_then_clause (init_if_stmt); 3259 finish_if_stmt (init_if_stmt); 3260 } 3261 3262 /* VARS is a list of variables with static storage duration which may 3263 need initialization and/or finalization. Remove those variables 3264 that don't really need to be initialized or finalized, and return 3265 the resulting list. The order in which the variables appear in 3266 VARS is in reverse order of the order in which they should actually 3267 be initialized. The list we return is in the unreversed order; 3268 i.e., the first variable should be initialized first. */ 3269 3270 static tree 3271 prune_vars_needing_no_initialization (tree *vars) 3272 { 3273 tree *var = vars; 3274 tree result = NULL_TREE; 3275 3276 while (*var) 3277 { 3278 tree t = *var; 3279 tree decl = TREE_VALUE (t); 3280 tree init = TREE_PURPOSE (t); 3281 3282 /* Deal gracefully with error. */ 3283 if (decl == error_mark_node) 3284 { 3285 var = &TREE_CHAIN (t); 3286 continue; 3287 } 3288 3289 /* The only things that can be initialized are variables. */ 3290 gcc_assert (TREE_CODE (decl) == VAR_DECL); 3291 3292 /* If this object is not defined, we don't need to do anything 3293 here. */ 3294 if (DECL_EXTERNAL (decl)) 3295 { 3296 var = &TREE_CHAIN (t); 3297 continue; 3298 } 3299 3300 /* Also, if the initializer already contains errors, we can bail 3301 out now. */ 3302 if (init && TREE_CODE (init) == TREE_LIST 3303 && value_member (error_mark_node, init)) 3304 { 3305 var = &TREE_CHAIN (t); 3306 continue; 3307 } 3308 3309 /* This variable is going to need initialization and/or 3310 finalization, so we add it to the list. */ 3311 *var = TREE_CHAIN (t); 3312 TREE_CHAIN (t) = result; 3313 result = t; 3314 } 3315 3316 return result; 3317 } 3318 3319 /* Make sure we have told the back end about all the variables in 3320 VARS. */ 3321 3322 static void 3323 write_out_vars (tree vars) 3324 { 3325 tree v; 3326 3327 for (v = vars; v; v = TREE_CHAIN (v)) 3328 { 3329 tree var = TREE_VALUE (v); 3330 if (!var_finalized_p (var)) 3331 { 3332 import_export_decl (var); 3333 rest_of_decl_compilation (var, 1, 1); 3334 } 3335 } 3336 } 3337 3338 /* Generate a static constructor (if CONSTRUCTOR_P) or destructor 3339 (otherwise) that will initialize all global objects with static 3340 storage duration having the indicated PRIORITY. */ 3341 3342 static void 3343 generate_ctor_or_dtor_function (bool constructor_p, int priority, 3344 location_t *locus) 3345 { 3346 char function_key; 3347 tree fndecl; 3348 tree body; 3349 size_t i; 3350 3351 input_location = *locus; 3352 /* ??? */ 3353 /* Was: locus->line++; */ 3354 3355 /* We use `I' to indicate initialization and `D' to indicate 3356 destruction. */ 3357 function_key = constructor_p ? 'I' : 'D'; 3358 3359 /* We emit the function lazily, to avoid generating empty 3360 global constructors and destructors. */ 3361 body = NULL_TREE; 3362 3363 /* For Objective-C++, we may need to initialize metadata found in this module. 3364 This must be done _before_ any other static initializations. */ 3365 if (c_dialect_objc () && (priority == DEFAULT_INIT_PRIORITY) 3366 && constructor_p && objc_static_init_needed_p ()) 3367 { 3368 body = start_objects (function_key, priority); 3369 objc_generate_static_init_call (NULL_TREE); 3370 } 3371 3372 /* Call the static storage duration function with appropriate 3373 arguments. */ 3374 FOR_EACH_VEC_ELT (tree, ssdf_decls, i, fndecl) 3375 { 3376 /* Calls to pure or const functions will expand to nothing. */ 3377 if (! (flags_from_decl_or_type (fndecl) & (ECF_CONST | ECF_PURE))) 3378 { 3379 tree call; 3380 3381 if (! body) 3382 body = start_objects (function_key, priority); 3383 3384 call = cp_build_function_call_nary (fndecl, tf_warning_or_error, 3385 build_int_cst (NULL_TREE, 3386 constructor_p), 3387 build_int_cst (NULL_TREE, 3388 priority), 3389 NULL_TREE); 3390 finish_expr_stmt (call); 3391 } 3392 } 3393 3394 /* Close out the function. */ 3395 if (body) 3396 finish_objects (function_key, priority, body); 3397 } 3398 3399 /* Generate constructor and destructor functions for the priority 3400 indicated by N. */ 3401 3402 static int 3403 generate_ctor_and_dtor_functions_for_priority (splay_tree_node n, void * data) 3404 { 3405 location_t *locus = (location_t *) data; 3406 int priority = (int) n->key; 3407 priority_info pi = (priority_info) n->value; 3408 3409 /* Generate the functions themselves, but only if they are really 3410 needed. */ 3411 if (pi->initializations_p) 3412 generate_ctor_or_dtor_function (/*constructor_p=*/true, priority, locus); 3413 if (pi->destructions_p) 3414 generate_ctor_or_dtor_function (/*constructor_p=*/false, priority, locus); 3415 3416 /* Keep iterating. */ 3417 return 0; 3418 } 3419 3420 /* Called via LANGHOOK_CALLGRAPH_ANALYZE_EXPR. It is supposed to mark 3421 decls referenced from front-end specific constructs; it will be called 3422 only for language-specific tree nodes. 3423 3424 Here we must deal with member pointers. */ 3425 3426 tree 3427 cxx_callgraph_analyze_expr (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED) 3428 { 3429 tree t = *tp; 3430 3431 switch (TREE_CODE (t)) 3432 { 3433 case PTRMEM_CST: 3434 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (t))) 3435 cgraph_mark_address_taken_node ( 3436 cgraph_get_create_node (PTRMEM_CST_MEMBER (t))); 3437 break; 3438 case BASELINK: 3439 if (TREE_CODE (BASELINK_FUNCTIONS (t)) == FUNCTION_DECL) 3440 cgraph_mark_address_taken_node ( 3441 cgraph_get_create_node (BASELINK_FUNCTIONS (t))); 3442 break; 3443 case VAR_DECL: 3444 if (DECL_CONTEXT (t) 3445 && flag_use_repository 3446 && TREE_CODE (DECL_CONTEXT (t)) == FUNCTION_DECL) 3447 /* If we need a static variable in a function, then we 3448 need the containing function. */ 3449 mark_decl_referenced (DECL_CONTEXT (t)); 3450 break; 3451 default: 3452 break; 3453 } 3454 3455 return NULL; 3456 } 3457 3458 /* Java requires that we be able to reference a local address for a 3459 method, and not be confused by PLT entries. If hidden aliases are 3460 supported, collect and return all the functions for which we should 3461 emit a hidden alias. */ 3462 3463 static struct pointer_set_t * 3464 collect_candidates_for_java_method_aliases (void) 3465 { 3466 struct cgraph_node *node; 3467 struct pointer_set_t *candidates = NULL; 3468 3469 #ifndef HAVE_GAS_HIDDEN 3470 return candidates; 3471 #endif 3472 3473 for (node = cgraph_nodes; node ; node = node->next) 3474 { 3475 tree fndecl = node->decl; 3476 3477 if (DECL_CONTEXT (fndecl) 3478 && TYPE_P (DECL_CONTEXT (fndecl)) 3479 && TYPE_FOR_JAVA (DECL_CONTEXT (fndecl)) 3480 && TARGET_USE_LOCAL_THUNK_ALIAS_P (fndecl)) 3481 { 3482 if (candidates == NULL) 3483 candidates = pointer_set_create (); 3484 pointer_set_insert (candidates, fndecl); 3485 } 3486 } 3487 3488 return candidates; 3489 } 3490 3491 3492 /* Java requires that we be able to reference a local address for a 3493 method, and not be confused by PLT entries. If hidden aliases are 3494 supported, emit one for each java function that we've emitted. 3495 CANDIDATES is the set of FUNCTION_DECLs that were gathered 3496 by collect_candidates_for_java_method_aliases. */ 3497 3498 static void 3499 build_java_method_aliases (struct pointer_set_t *candidates) 3500 { 3501 struct cgraph_node *node; 3502 3503 #ifndef HAVE_GAS_HIDDEN 3504 return; 3505 #endif 3506 3507 for (node = cgraph_nodes; node ; node = node->next) 3508 { 3509 tree fndecl = node->decl; 3510 3511 if (TREE_ASM_WRITTEN (fndecl) 3512 && pointer_set_contains (candidates, fndecl)) 3513 { 3514 /* Mangle the name in a predictable way; we need to reference 3515 this from a java compiled object file. */ 3516 tree oid, nid, alias; 3517 const char *oname; 3518 char *nname; 3519 3520 oid = DECL_ASSEMBLER_NAME (fndecl); 3521 oname = IDENTIFIER_POINTER (oid); 3522 gcc_assert (oname[0] == '_' && oname[1] == 'Z'); 3523 nname = ACONCAT (("_ZGA", oname+2, NULL)); 3524 nid = get_identifier (nname); 3525 3526 alias = make_alias_for (fndecl, nid); 3527 TREE_PUBLIC (alias) = 1; 3528 DECL_VISIBILITY (alias) = VISIBILITY_HIDDEN; 3529 3530 assemble_alias (alias, oid); 3531 } 3532 } 3533 } 3534 3535 /* Return C++ property of T, based on given operation OP. */ 3536 3537 static int 3538 cpp_check (tree t, cpp_operation op) 3539 { 3540 switch (op) 3541 { 3542 case IS_ABSTRACT: 3543 return DECL_PURE_VIRTUAL_P (t); 3544 case IS_CONSTRUCTOR: 3545 return DECL_CONSTRUCTOR_P (t); 3546 case IS_DESTRUCTOR: 3547 return DECL_DESTRUCTOR_P (t); 3548 case IS_COPY_CONSTRUCTOR: 3549 return DECL_COPY_CONSTRUCTOR_P (t); 3550 case IS_TEMPLATE: 3551 return TREE_CODE (t) == TEMPLATE_DECL; 3552 default: 3553 return 0; 3554 } 3555 } 3556 3557 /* Collect source file references recursively, starting from NAMESPC. */ 3558 3559 static void 3560 collect_source_refs (tree namespc) 3561 { 3562 tree t; 3563 3564 if (!namespc) 3565 return; 3566 3567 /* Iterate over names in this name space. */ 3568 for (t = NAMESPACE_LEVEL (namespc)->names; t; t = TREE_CHAIN (t)) 3569 if (!DECL_IS_BUILTIN (t) ) 3570 collect_source_ref (DECL_SOURCE_FILE (t)); 3571 3572 /* Dump siblings, if any */ 3573 collect_source_refs (TREE_CHAIN (namespc)); 3574 3575 /* Dump children, if any */ 3576 collect_source_refs (NAMESPACE_LEVEL (namespc)->namespaces); 3577 } 3578 3579 /* Collect decls relevant to SOURCE_FILE from all namespaces recursively, 3580 starting from NAMESPC. */ 3581 3582 static void 3583 collect_ada_namespace (tree namespc, const char *source_file) 3584 { 3585 if (!namespc) 3586 return; 3587 3588 /* Collect decls from this namespace */ 3589 collect_ada_nodes (NAMESPACE_LEVEL (namespc)->names, source_file); 3590 3591 /* Collect siblings, if any */ 3592 collect_ada_namespace (TREE_CHAIN (namespc), source_file); 3593 3594 /* Collect children, if any */ 3595 collect_ada_namespace (NAMESPACE_LEVEL (namespc)->namespaces, source_file); 3596 } 3597 3598 /* Returns true iff there is a definition available for variable or 3599 function DECL. */ 3600 3601 static bool 3602 decl_defined_p (tree decl) 3603 { 3604 if (TREE_CODE (decl) == FUNCTION_DECL) 3605 return (DECL_INITIAL (decl) != NULL_TREE); 3606 else 3607 { 3608 gcc_assert (TREE_CODE (decl) == VAR_DECL); 3609 return !DECL_EXTERNAL (decl); 3610 } 3611 } 3612 3613 /* Nonzero for a VAR_DECL whose value can be used in a constant expression. 3614 3615 [expr.const] 3616 3617 An integral constant-expression can only involve ... const 3618 variables of integral or enumeration types initialized with 3619 constant expressions ... 3620 3621 C++0x also allows constexpr variables and temporaries initialized 3622 with constant expressions. We handle the former here, but the latter 3623 are just folded away in cxx_eval_constant_expression. 3624 3625 The standard does not require that the expression be non-volatile. 3626 G++ implements the proposed correction in DR 457. */ 3627 3628 bool 3629 decl_constant_var_p (tree decl) 3630 { 3631 if (!decl_maybe_constant_var_p (decl)) 3632 return false; 3633 3634 /* We don't know if a template static data member is initialized with 3635 a constant expression until we instantiate its initializer. Even 3636 in the case of a constexpr variable, we can't treat it as a 3637 constant until its initializer is complete in case it's used in 3638 its own initializer. */ 3639 mark_used (decl); 3640 return DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl); 3641 } 3642 3643 /* Returns true if DECL could be a symbolic constant variable, depending on 3644 its initializer. */ 3645 3646 bool 3647 decl_maybe_constant_var_p (tree decl) 3648 { 3649 tree type = TREE_TYPE (decl); 3650 if (TREE_CODE (decl) != VAR_DECL) 3651 return false; 3652 if (DECL_DECLARED_CONSTEXPR_P (decl)) 3653 return true; 3654 return (CP_TYPE_CONST_NON_VOLATILE_P (type) 3655 && INTEGRAL_OR_ENUMERATION_TYPE_P (type)); 3656 } 3657 3658 /* Complain that DECL uses a type with no linkage but is never defined. */ 3659 3660 static void 3661 no_linkage_error (tree decl) 3662 { 3663 tree t = no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false); 3664 if (TYPE_ANONYMOUS_P (t)) 3665 { 3666 permerror (0, "%q+#D, declared using anonymous type, " 3667 "is used but never defined", decl); 3668 if (is_typedef_decl (TYPE_NAME (t))) 3669 permerror (0, "%q+#D does not refer to the unqualified type, " 3670 "so it is not used for linkage", TYPE_NAME (t)); 3671 } 3672 else 3673 permerror (0, "%q+#D, declared using local type %qT, " 3674 "is used but never defined", decl, t); 3675 } 3676 3677 /* Collect declarations from all namespaces relevant to SOURCE_FILE. */ 3678 3679 static void 3680 collect_all_refs (const char *source_file) 3681 { 3682 collect_ada_namespace (global_namespace, source_file); 3683 } 3684 3685 /* Clear DECL_EXTERNAL for NODE. */ 3686 3687 static bool 3688 clear_decl_external (struct cgraph_node *node, void *data ATTRIBUTE_UNUSED) 3689 { 3690 DECL_EXTERNAL (node->decl) = 0; 3691 return false; 3692 } 3693 3694 /* This routine is called at the end of compilation. 3695 Its job is to create all the code needed to initialize and 3696 destroy the global aggregates. We do the destruction 3697 first, since that way we only need to reverse the decls once. */ 3698 3699 void 3700 cp_write_global_declarations (void) 3701 { 3702 tree vars; 3703 bool reconsider; 3704 size_t i; 3705 location_t locus; 3706 unsigned ssdf_count = 0; 3707 int retries = 0; 3708 tree decl; 3709 struct pointer_set_t *candidates; 3710 3711 locus = input_location; 3712 at_eof = 1; 3713 3714 /* Bad parse errors. Just forget about it. */ 3715 if (! global_bindings_p () || current_class_type 3716 || !VEC_empty (tree,decl_namespace_list)) 3717 return; 3718 3719 if (pch_file) 3720 c_common_write_pch (); 3721 3722 cgraph_process_same_body_aliases (); 3723 3724 /* Handle -fdump-ada-spec[-slim] */ 3725 if (dump_enabled_p (TDI_ada)) 3726 { 3727 if (get_dump_file_info (TDI_ada)->flags & TDF_SLIM) 3728 collect_source_ref (main_input_filename); 3729 else 3730 collect_source_refs (global_namespace); 3731 3732 dump_ada_specs (collect_all_refs, cpp_check); 3733 } 3734 3735 /* FIXME - huh? was input_line -= 1;*/ 3736 3737 timevar_start (TV_PHASE_DEFERRED); 3738 3739 /* We now have to write out all the stuff we put off writing out. 3740 These include: 3741 3742 o Template specializations that we have not yet instantiated, 3743 but which are needed. 3744 o Initialization and destruction for non-local objects with 3745 static storage duration. (Local objects with static storage 3746 duration are initialized when their scope is first entered, 3747 and are cleaned up via atexit.) 3748 o Virtual function tables. 3749 3750 All of these may cause others to be needed. For example, 3751 instantiating one function may cause another to be needed, and 3752 generating the initializer for an object may cause templates to be 3753 instantiated, etc., etc. */ 3754 3755 emit_support_tinfos (); 3756 3757 do 3758 { 3759 tree t; 3760 tree decl; 3761 3762 reconsider = false; 3763 3764 /* If there are templates that we've put off instantiating, do 3765 them now. */ 3766 instantiate_pending_templates (retries); 3767 ggc_collect (); 3768 3769 /* Write out virtual tables as required. Note that writing out 3770 the virtual table for a template class may cause the 3771 instantiation of members of that class. If we write out 3772 vtables then we remove the class from our list so we don't 3773 have to look at it again. */ 3774 3775 while (keyed_classes != NULL_TREE 3776 && maybe_emit_vtables (TREE_VALUE (keyed_classes))) 3777 { 3778 reconsider = true; 3779 keyed_classes = TREE_CHAIN (keyed_classes); 3780 } 3781 3782 t = keyed_classes; 3783 if (t != NULL_TREE) 3784 { 3785 tree next = TREE_CHAIN (t); 3786 3787 while (next) 3788 { 3789 if (maybe_emit_vtables (TREE_VALUE (next))) 3790 { 3791 reconsider = true; 3792 TREE_CHAIN (t) = TREE_CHAIN (next); 3793 } 3794 else 3795 t = next; 3796 3797 next = TREE_CHAIN (t); 3798 } 3799 } 3800 3801 /* Write out needed type info variables. We have to be careful 3802 looping through unemitted decls, because emit_tinfo_decl may 3803 cause other variables to be needed. New elements will be 3804 appended, and we remove from the vector those that actually 3805 get emitted. */ 3806 for (i = VEC_length (tree, unemitted_tinfo_decls); 3807 VEC_iterate (tree, unemitted_tinfo_decls, --i, t);) 3808 if (emit_tinfo_decl (t)) 3809 { 3810 reconsider = true; 3811 VEC_unordered_remove (tree, unemitted_tinfo_decls, i); 3812 } 3813 3814 /* The list of objects with static storage duration is built up 3815 in reverse order. We clear STATIC_AGGREGATES so that any new 3816 aggregates added during the initialization of these will be 3817 initialized in the correct order when we next come around the 3818 loop. */ 3819 vars = prune_vars_needing_no_initialization (&static_aggregates); 3820 3821 if (vars) 3822 { 3823 /* We need to start a new initialization function each time 3824 through the loop. That's because we need to know which 3825 vtables have been referenced, and TREE_SYMBOL_REFERENCED 3826 isn't computed until a function is finished, and written 3827 out. That's a deficiency in the back end. When this is 3828 fixed, these initialization functions could all become 3829 inline, with resulting performance improvements. */ 3830 tree ssdf_body; 3831 3832 /* Set the line and file, so that it is obviously not from 3833 the source file. */ 3834 input_location = locus; 3835 ssdf_body = start_static_storage_duration_function (ssdf_count); 3836 3837 /* Make sure the back end knows about all the variables. */ 3838 write_out_vars (vars); 3839 3840 /* First generate code to do all the initializations. */ 3841 if (vars) 3842 do_static_initialization_or_destruction (vars, /*initp=*/true); 3843 3844 /* Then, generate code to do all the destructions. Do these 3845 in reverse order so that the most recently constructed 3846 variable is the first destroyed. If we're using 3847 __cxa_atexit, then we don't need to do this; functions 3848 were registered at initialization time to destroy the 3849 local statics. */ 3850 if (!flag_use_cxa_atexit && vars) 3851 { 3852 vars = nreverse (vars); 3853 do_static_initialization_or_destruction (vars, /*initp=*/false); 3854 } 3855 else 3856 vars = NULL_TREE; 3857 3858 /* Finish up the static storage duration function for this 3859 round. */ 3860 input_location = locus; 3861 finish_static_storage_duration_function (ssdf_body); 3862 3863 /* All those initializations and finalizations might cause 3864 us to need more inline functions, more template 3865 instantiations, etc. */ 3866 reconsider = true; 3867 ssdf_count++; 3868 /* ??? was: locus.line++; */ 3869 } 3870 3871 /* Go through the set of inline functions whose bodies have not 3872 been emitted yet. If out-of-line copies of these functions 3873 are required, emit them. */ 3874 FOR_EACH_VEC_ELT (tree, deferred_fns, i, decl) 3875 { 3876 /* Does it need synthesizing? */ 3877 if (DECL_DEFAULTED_FN (decl) && ! DECL_INITIAL (decl) 3878 && (! DECL_REALLY_EXTERN (decl) || possibly_inlined_p (decl))) 3879 { 3880 /* Even though we're already at the top-level, we push 3881 there again. That way, when we pop back a few lines 3882 hence, all of our state is restored. Otherwise, 3883 finish_function doesn't clean things up, and we end 3884 up with CURRENT_FUNCTION_DECL set. */ 3885 push_to_top_level (); 3886 /* The decl's location will mark where it was first 3887 needed. Save that so synthesize method can indicate 3888 where it was needed from, in case of error */ 3889 input_location = DECL_SOURCE_LOCATION (decl); 3890 synthesize_method (decl); 3891 pop_from_top_level (); 3892 reconsider = true; 3893 } 3894 3895 if (!DECL_SAVED_TREE (decl)) 3896 continue; 3897 3898 /* We lie to the back end, pretending that some functions 3899 are not defined when they really are. This keeps these 3900 functions from being put out unnecessarily. But, we must 3901 stop lying when the functions are referenced, or if they 3902 are not comdat since they need to be put out now. If 3903 DECL_INTERFACE_KNOWN, then we have already set 3904 DECL_EXTERNAL appropriately, so there's no need to check 3905 again, and we do not want to clear DECL_EXTERNAL if a 3906 previous call to import_export_decl set it. 3907 3908 This is done in a separate for cycle, because if some 3909 deferred function is contained in another deferred 3910 function later in deferred_fns varray, 3911 rest_of_compilation would skip this function and we 3912 really cannot expand the same function twice. */ 3913 import_export_decl (decl); 3914 if (DECL_NOT_REALLY_EXTERN (decl) 3915 && DECL_INITIAL (decl) 3916 && decl_needed_p (decl)) 3917 { 3918 struct cgraph_node *node, *next; 3919 3920 node = cgraph_get_node (decl); 3921 if (node->same_body_alias) 3922 node = cgraph_alias_aliased_node (node); 3923 3924 cgraph_for_node_and_aliases (node, clear_decl_external, 3925 NULL, true); 3926 /* If we mark !DECL_EXTERNAL one of the symbols in some comdat 3927 group, we need to mark all symbols in the same comdat group 3928 that way. */ 3929 if (node->same_comdat_group) 3930 for (next = node->same_comdat_group; 3931 next != node; 3932 next = next->same_comdat_group) 3933 cgraph_for_node_and_aliases (next, clear_decl_external, 3934 NULL, true); 3935 } 3936 3937 /* If we're going to need to write this function out, and 3938 there's already a body for it, create RTL for it now. 3939 (There might be no body if this is a method we haven't 3940 gotten around to synthesizing yet.) */ 3941 if (!DECL_EXTERNAL (decl) 3942 && decl_needed_p (decl) 3943 && !TREE_ASM_WRITTEN (decl) 3944 && !cgraph_get_node (decl)->local.finalized) 3945 { 3946 /* We will output the function; no longer consider it in this 3947 loop. */ 3948 DECL_DEFER_OUTPUT (decl) = 0; 3949 /* Generate RTL for this function now that we know we 3950 need it. */ 3951 expand_or_defer_fn (decl); 3952 /* If we're compiling -fsyntax-only pretend that this 3953 function has been written out so that we don't try to 3954 expand it again. */ 3955 if (flag_syntax_only) 3956 TREE_ASM_WRITTEN (decl) = 1; 3957 reconsider = true; 3958 } 3959 } 3960 3961 if (walk_namespaces (wrapup_globals_for_namespace, /*data=*/0)) 3962 reconsider = true; 3963 3964 /* Static data members are just like namespace-scope globals. */ 3965 FOR_EACH_VEC_ELT (tree, pending_statics, i, decl) 3966 { 3967 if (var_finalized_p (decl) || DECL_REALLY_EXTERN (decl) 3968 /* Don't write it out if we haven't seen a definition. */ 3969 || DECL_IN_AGGR_P (decl)) 3970 continue; 3971 import_export_decl (decl); 3972 /* If this static data member is needed, provide it to the 3973 back end. */ 3974 if (DECL_NOT_REALLY_EXTERN (decl) && decl_needed_p (decl)) 3975 DECL_EXTERNAL (decl) = 0; 3976 } 3977 if (VEC_length (tree, pending_statics) != 0 3978 && wrapup_global_declarations (VEC_address (tree, pending_statics), 3979 VEC_length (tree, pending_statics))) 3980 reconsider = true; 3981 3982 retries++; 3983 } 3984 while (reconsider); 3985 3986 /* All used inline functions must have a definition at this point. */ 3987 FOR_EACH_VEC_ELT (tree, deferred_fns, i, decl) 3988 { 3989 if (/* Check online inline functions that were actually used. */ 3990 DECL_ODR_USED (decl) && DECL_DECLARED_INLINE_P (decl) 3991 /* If the definition actually was available here, then the 3992 fact that the function was not defined merely represents 3993 that for some reason (use of a template repository, 3994 #pragma interface, etc.) we decided not to emit the 3995 definition here. */ 3996 && !DECL_INITIAL (decl) 3997 /* Don't complain if the template was defined. */ 3998 && !(DECL_TEMPLATE_INSTANTIATION (decl) 3999 && DECL_INITIAL (DECL_TEMPLATE_RESULT 4000 (template_for_substitution (decl))))) 4001 { 4002 warning (0, "inline function %q+D used but never defined", decl); 4003 /* Avoid a duplicate warning from check_global_declaration_1. */ 4004 TREE_NO_WARNING (decl) = 1; 4005 } 4006 } 4007 4008 /* So must decls that use a type with no linkage. */ 4009 FOR_EACH_VEC_ELT (tree, no_linkage_decls, i, decl) 4010 if (!decl_defined_p (decl)) 4011 no_linkage_error (decl); 4012 4013 /* Then, do the Objective-C stuff. This is where all the 4014 Objective-C module stuff gets generated (symtab, 4015 class/protocol/selector lists etc). This must be done after C++ 4016 templates, destructors etc. so that selectors used in C++ 4017 templates are properly allocated. */ 4018 if (c_dialect_objc ()) 4019 objc_write_global_declarations (); 4020 4021 /* We give C linkage to static constructors and destructors. */ 4022 push_lang_context (lang_name_c); 4023 4024 /* Generate initialization and destruction functions for all 4025 priorities for which they are required. */ 4026 if (priority_info_map) 4027 splay_tree_foreach (priority_info_map, 4028 generate_ctor_and_dtor_functions_for_priority, 4029 /*data=*/&locus); 4030 else if (c_dialect_objc () && objc_static_init_needed_p ()) 4031 /* If this is obj-c++ and we need a static init, call 4032 generate_ctor_or_dtor_function. */ 4033 generate_ctor_or_dtor_function (/*constructor_p=*/true, 4034 DEFAULT_INIT_PRIORITY, &locus); 4035 4036 /* We're done with the splay-tree now. */ 4037 if (priority_info_map) 4038 splay_tree_delete (priority_info_map); 4039 4040 /* Generate any missing aliases. */ 4041 maybe_apply_pending_pragma_weaks (); 4042 4043 /* We're done with static constructors, so we can go back to "C++" 4044 linkage now. */ 4045 pop_lang_context (); 4046 4047 /* Collect candidates for Java hidden aliases. */ 4048 candidates = collect_candidates_for_java_method_aliases (); 4049 4050 timevar_stop (TV_PHASE_DEFERRED); 4051 timevar_start (TV_PHASE_CGRAPH); 4052 4053 cgraph_finalize_compilation_unit (); 4054 4055 timevar_stop (TV_PHASE_CGRAPH); 4056 timevar_start (TV_PHASE_CHECK_DBGINFO); 4057 4058 /* Now, issue warnings about static, but not defined, functions, 4059 etc., and emit debugging information. */ 4060 walk_namespaces (wrapup_globals_for_namespace, /*data=*/&reconsider); 4061 if (VEC_length (tree, pending_statics) != 0) 4062 { 4063 check_global_declarations (VEC_address (tree, pending_statics), 4064 VEC_length (tree, pending_statics)); 4065 emit_debug_global_declarations (VEC_address (tree, pending_statics), 4066 VEC_length (tree, pending_statics)); 4067 } 4068 4069 perform_deferred_noexcept_checks (); 4070 4071 /* Generate hidden aliases for Java. */ 4072 if (candidates) 4073 { 4074 build_java_method_aliases (candidates); 4075 pointer_set_destroy (candidates); 4076 } 4077 4078 finish_repo (); 4079 4080 /* The entire file is now complete. If requested, dump everything 4081 to a file. */ 4082 { 4083 int flags; 4084 FILE *stream = dump_begin (TDI_tu, &flags); 4085 4086 if (stream) 4087 { 4088 dump_node (global_namespace, flags & ~TDF_SLIM, stream); 4089 dump_end (TDI_tu, stream); 4090 } 4091 } 4092 4093 if (flag_detailed_statistics) 4094 { 4095 dump_tree_statistics (); 4096 dump_time_statistics (); 4097 } 4098 input_location = locus; 4099 4100 #ifdef ENABLE_CHECKING 4101 validate_conversion_obstack (); 4102 #endif /* ENABLE_CHECKING */ 4103 4104 timevar_stop (TV_PHASE_CHECK_DBGINFO); 4105 } 4106 4107 /* FN is an OFFSET_REF, DOTSTAR_EXPR or MEMBER_REF indicating the 4108 function to call in parse-tree form; it has not yet been 4109 semantically analyzed. ARGS are the arguments to the function. 4110 They have already been semantically analyzed. This may change 4111 ARGS. */ 4112 4113 tree 4114 build_offset_ref_call_from_tree (tree fn, VEC(tree,gc) **args) 4115 { 4116 tree orig_fn; 4117 VEC(tree,gc) *orig_args = NULL; 4118 tree expr; 4119 tree object; 4120 4121 orig_fn = fn; 4122 object = TREE_OPERAND (fn, 0); 4123 4124 if (processing_template_decl) 4125 { 4126 gcc_assert (TREE_CODE (fn) == DOTSTAR_EXPR 4127 || TREE_CODE (fn) == MEMBER_REF); 4128 if (type_dependent_expression_p (fn) 4129 || any_type_dependent_arguments_p (*args)) 4130 return build_nt_call_vec (fn, *args); 4131 4132 orig_args = make_tree_vector_copy (*args); 4133 4134 /* Transform the arguments and add the implicit "this" 4135 parameter. That must be done before the FN is transformed 4136 because we depend on the form of FN. */ 4137 make_args_non_dependent (*args); 4138 object = build_non_dependent_expr (object); 4139 if (TREE_CODE (TREE_TYPE (fn)) == METHOD_TYPE) 4140 { 4141 if (TREE_CODE (fn) == DOTSTAR_EXPR) 4142 object = cp_build_addr_expr (object, tf_warning_or_error); 4143 VEC_safe_insert (tree, gc, *args, 0, object); 4144 } 4145 /* Now that the arguments are done, transform FN. */ 4146 fn = build_non_dependent_expr (fn); 4147 } 4148 4149 /* A qualified name corresponding to a bound pointer-to-member is 4150 represented as an OFFSET_REF: 4151 4152 struct B { void g(); }; 4153 void (B::*p)(); 4154 void B::g() { (this->*p)(); } */ 4155 if (TREE_CODE (fn) == OFFSET_REF) 4156 { 4157 tree object_addr = cp_build_addr_expr (object, tf_warning_or_error); 4158 fn = TREE_OPERAND (fn, 1); 4159 fn = get_member_function_from_ptrfunc (&object_addr, fn); 4160 VEC_safe_insert (tree, gc, *args, 0, object_addr); 4161 } 4162 4163 if (CLASS_TYPE_P (TREE_TYPE (fn))) 4164 expr = build_op_call (fn, args, tf_warning_or_error); 4165 else 4166 expr = cp_build_function_call_vec (fn, args, tf_warning_or_error); 4167 if (processing_template_decl && expr != error_mark_node) 4168 expr = build_min_non_dep_call_vec (expr, orig_fn, orig_args); 4169 4170 if (orig_args != NULL) 4171 release_tree_vector (orig_args); 4172 4173 return expr; 4174 } 4175 4176 4177 void 4178 check_default_args (tree x) 4179 { 4180 tree arg = TYPE_ARG_TYPES (TREE_TYPE (x)); 4181 bool saw_def = false; 4182 int i = 0 - (TREE_CODE (TREE_TYPE (x)) == METHOD_TYPE); 4183 for (; arg && arg != void_list_node; arg = TREE_CHAIN (arg), ++i) 4184 { 4185 if (TREE_PURPOSE (arg)) 4186 saw_def = true; 4187 else if (saw_def) 4188 { 4189 error ("default argument missing for parameter %P of %q+#D", i, x); 4190 TREE_PURPOSE (arg) = error_mark_node; 4191 } 4192 } 4193 } 4194 4195 /* Return true if function DECL can be inlined. This is used to force 4196 instantiation of methods that might be interesting for inlining. */ 4197 bool 4198 possibly_inlined_p (tree decl) 4199 { 4200 gcc_assert (TREE_CODE (decl) == FUNCTION_DECL); 4201 if (DECL_UNINLINABLE (decl)) 4202 return false; 4203 if (!optimize || pragma_java_exceptions) 4204 return DECL_DECLARED_INLINE_P (decl); 4205 /* When optimizing, we might inline everything when flatten 4206 attribute or heuristics inlining for size or autoinlining 4207 is used. */ 4208 return true; 4209 } 4210 4211 /* Mark DECL (either a _DECL or a BASELINK) as "used" in the program. 4212 If DECL is a specialization or implicitly declared class member, 4213 generate the actual definition. Return false if something goes 4214 wrong, true otherwise. */ 4215 4216 bool 4217 mark_used (tree decl) 4218 { 4219 /* If DECL is a BASELINK for a single function, then treat it just 4220 like the DECL for the function. Otherwise, if the BASELINK is 4221 for an overloaded function, we don't know which function was 4222 actually used until after overload resolution. */ 4223 if (BASELINK_P (decl)) 4224 { 4225 decl = BASELINK_FUNCTIONS (decl); 4226 if (really_overloaded_fn (decl)) 4227 return true; 4228 decl = OVL_CURRENT (decl); 4229 } 4230 4231 /* Set TREE_USED for the benefit of -Wunused. */ 4232 TREE_USED (decl) = 1; 4233 if (DECL_CLONED_FUNCTION_P (decl)) 4234 TREE_USED (DECL_CLONED_FUNCTION (decl)) = 1; 4235 4236 if (TREE_CODE (decl) == FUNCTION_DECL 4237 && DECL_DELETED_FN (decl)) 4238 { 4239 if (DECL_ARTIFICIAL (decl)) 4240 { 4241 if (DECL_OVERLOADED_OPERATOR_P (decl) == TYPE_EXPR 4242 && LAMBDA_TYPE_P (DECL_CONTEXT (decl))) 4243 { 4244 /* We mark a lambda conversion op as deleted if we can't 4245 generate it properly; see maybe_add_lambda_conv_op. */ 4246 sorry ("converting lambda which uses %<...%> to " 4247 "function pointer"); 4248 return false; 4249 } 4250 } 4251 error ("use of deleted function %qD", decl); 4252 if (!maybe_explain_implicit_delete (decl)) 4253 error_at (DECL_SOURCE_LOCATION (decl), "declared here"); 4254 return false; 4255 } 4256 4257 /* We can only check DECL_ODR_USED on variables or functions with 4258 DECL_LANG_SPECIFIC set, and these are also the only decls that we 4259 might need special handling for. */ 4260 if ((TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL) 4261 || DECL_LANG_SPECIFIC (decl) == NULL 4262 || DECL_THUNK_P (decl)) 4263 return true; 4264 4265 /* We only want to do this processing once. We don't need to keep trying 4266 to instantiate inline templates, because unit-at-a-time will make sure 4267 we get them compiled before functions that want to inline them. */ 4268 if (DECL_ODR_USED (decl)) 4269 return true; 4270 4271 /* If within finish_function, defer the rest until that function 4272 finishes, otherwise it might recurse. */ 4273 if (defer_mark_used_calls) 4274 { 4275 VEC_safe_push (tree, gc, deferred_mark_used_calls, decl); 4276 return true; 4277 } 4278 4279 if (TREE_CODE (decl) == FUNCTION_DECL) 4280 maybe_instantiate_noexcept (decl); 4281 4282 /* Normally, we can wait until instantiation-time to synthesize DECL. 4283 However, if DECL is a static data member initialized with a constant 4284 or a constexpr function, we need it right now because a reference to 4285 such a data member or a call to such function is not value-dependent. */ 4286 if ((decl_maybe_constant_var_p (decl) 4287 || (TREE_CODE (decl) == FUNCTION_DECL 4288 && DECL_DECLARED_CONSTEXPR_P (decl))) 4289 && DECL_LANG_SPECIFIC (decl) 4290 && DECL_TEMPLATE_INFO (decl) 4291 && !uses_template_parms (DECL_TI_ARGS (decl))) 4292 { 4293 /* Instantiating a function will result in garbage collection. We 4294 must treat this situation as if we were within the body of a 4295 function so as to avoid collecting live data only referenced from 4296 the stack (such as overload resolution candidates). */ 4297 ++function_depth; 4298 instantiate_decl (decl, /*defer_ok=*/false, 4299 /*expl_inst_class_mem_p=*/false); 4300 --function_depth; 4301 } 4302 4303 /* If we don't need a value, then we don't need to synthesize DECL. */ 4304 if (cp_unevaluated_operand != 0) 4305 return true; 4306 4307 if (processing_template_decl) 4308 return true; 4309 4310 /* Check this too in case we're within fold_non_dependent_expr. */ 4311 if (DECL_TEMPLATE_INFO (decl) 4312 && uses_template_parms (DECL_TI_ARGS (decl))) 4313 return true; 4314 4315 DECL_ODR_USED (decl) = 1; 4316 if (DECL_CLONED_FUNCTION_P (decl)) 4317 DECL_ODR_USED (DECL_CLONED_FUNCTION (decl)) = 1; 4318 4319 /* DR 757: A type without linkage shall not be used as the type of a 4320 variable or function with linkage, unless 4321 o the variable or function has extern "C" linkage (7.5 [dcl.link]), or 4322 o the variable or function is not used (3.2 [basic.def.odr]) or is 4323 defined in the same translation unit. */ 4324 if (cxx_dialect > cxx98 4325 && decl_linkage (decl) != lk_none 4326 && !DECL_EXTERN_C_P (decl) 4327 && !DECL_ARTIFICIAL (decl) 4328 && !decl_defined_p (decl) 4329 && no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false)) 4330 { 4331 if (is_local_extern (decl)) 4332 /* There's no way to define a local extern, and adding it to 4333 the vector interferes with GC, so give an error now. */ 4334 no_linkage_error (decl); 4335 else 4336 VEC_safe_push (tree, gc, no_linkage_decls, decl); 4337 } 4338 4339 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_DECLARED_INLINE_P (decl) 4340 && !DECL_INITIAL (decl) && !DECL_ARTIFICIAL (decl)) 4341 /* Remember it, so we can check it was defined. */ 4342 note_vague_linkage_fn (decl); 4343 4344 /* Is it a synthesized method that needs to be synthesized? */ 4345 if (TREE_CODE (decl) == FUNCTION_DECL 4346 && DECL_NONSTATIC_MEMBER_FUNCTION_P (decl) 4347 && DECL_DEFAULTED_FN (decl) 4348 /* A function defaulted outside the class is synthesized either by 4349 cp_finish_decl or instantiate_decl. */ 4350 && !DECL_DEFAULTED_OUTSIDE_CLASS_P (decl) 4351 && ! DECL_INITIAL (decl)) 4352 { 4353 /* Defer virtual destructors so that thunks get the right 4354 linkage. */ 4355 if (DECL_VIRTUAL_P (decl) && !at_eof) 4356 { 4357 note_vague_linkage_fn (decl); 4358 return true; 4359 } 4360 4361 /* Remember the current location for a function we will end up 4362 synthesizing. Then we can inform the user where it was 4363 required in the case of error. */ 4364 DECL_SOURCE_LOCATION (decl) = input_location; 4365 4366 /* Synthesizing an implicitly defined member function will result in 4367 garbage collection. We must treat this situation as if we were 4368 within the body of a function so as to avoid collecting live data 4369 on the stack (such as overload resolution candidates). 4370 4371 We could just let cp_write_global_declarations handle synthesizing 4372 this function by adding it to deferred_fns, but doing 4373 it at the use site produces better error messages. */ 4374 ++function_depth; 4375 synthesize_method (decl); 4376 --function_depth; 4377 /* If this is a synthesized method we don't need to 4378 do the instantiation test below. */ 4379 } 4380 else if ((TREE_CODE (decl) == FUNCTION_DECL || TREE_CODE (decl) == VAR_DECL) 4381 && DECL_TEMPLATE_INFO (decl) 4382 && (!DECL_EXPLICIT_INSTANTIATION (decl) 4383 || always_instantiate_p (decl))) 4384 /* If this is a function or variable that is an instance of some 4385 template, we now know that we will need to actually do the 4386 instantiation. We check that DECL is not an explicit 4387 instantiation because that is not checked in instantiate_decl. 4388 4389 We put off instantiating functions in order to improve compile 4390 times. Maintaining a stack of active functions is expensive, 4391 and the inliner knows to instantiate any functions it might 4392 need. Therefore, we always try to defer instantiation. */ 4393 { 4394 ++function_depth; 4395 instantiate_decl (decl, /*defer_ok=*/true, 4396 /*expl_inst_class_mem_p=*/false); 4397 --function_depth; 4398 } 4399 4400 return true; 4401 } 4402 4403 #include "gt-cp-decl2.h" 4404