1 /* Language-dependent node constructors for parse phase of GNU compiler. 2 Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009, 2010, 2011 4 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 #include "config.h" 24 #include "system.h" 25 #include "coretypes.h" 26 #include "tm.h" 27 #include "tree.h" 28 #include "cp-tree.h" 29 #include "flags.h" 30 #include "tree-inline.h" 31 #include "debug.h" 32 #include "convert.h" 33 #include "cgraph.h" 34 #include "splay-tree.h" 35 #include "gimple.h" /* gimple_has_body_p */ 36 37 static tree bot_manip (tree *, int *, void *); 38 static tree bot_replace (tree *, int *, void *); 39 static int list_hash_eq (const void *, const void *); 40 static hashval_t list_hash_pieces (tree, tree, tree); 41 static hashval_t list_hash (const void *); 42 static tree build_target_expr (tree, tree, tsubst_flags_t); 43 static tree count_trees_r (tree *, int *, void *); 44 static tree verify_stmt_tree_r (tree *, int *, void *); 45 static tree build_local_temp (tree); 46 47 static tree handle_java_interface_attribute (tree *, tree, tree, int, bool *); 48 static tree handle_com_interface_attribute (tree *, tree, tree, int, bool *); 49 static tree handle_init_priority_attribute (tree *, tree, tree, int, bool *); 50 51 /* If REF is an lvalue, returns the kind of lvalue that REF is. 52 Otherwise, returns clk_none. */ 53 54 cp_lvalue_kind 55 lvalue_kind (const_tree ref) 56 { 57 cp_lvalue_kind op1_lvalue_kind = clk_none; 58 cp_lvalue_kind op2_lvalue_kind = clk_none; 59 60 /* Expressions of reference type are sometimes wrapped in 61 INDIRECT_REFs. INDIRECT_REFs are just internal compiler 62 representation, not part of the language, so we have to look 63 through them. */ 64 if (REFERENCE_REF_P (ref)) 65 return lvalue_kind (TREE_OPERAND (ref, 0)); 66 67 if (TREE_TYPE (ref) 68 && TREE_CODE (TREE_TYPE (ref)) == REFERENCE_TYPE) 69 { 70 /* unnamed rvalue references are rvalues */ 71 if (TYPE_REF_IS_RVALUE (TREE_TYPE (ref)) 72 && TREE_CODE (ref) != PARM_DECL 73 && TREE_CODE (ref) != VAR_DECL 74 && TREE_CODE (ref) != COMPONENT_REF 75 /* Functions are always lvalues. */ 76 && TREE_CODE (TREE_TYPE (TREE_TYPE (ref))) != FUNCTION_TYPE) 77 return clk_rvalueref; 78 79 /* lvalue references and named rvalue references are lvalues. */ 80 return clk_ordinary; 81 } 82 83 if (ref == current_class_ptr) 84 return clk_none; 85 86 switch (TREE_CODE (ref)) 87 { 88 case SAVE_EXPR: 89 return clk_none; 90 /* preincrements and predecrements are valid lvals, provided 91 what they refer to are valid lvals. */ 92 case PREINCREMENT_EXPR: 93 case PREDECREMENT_EXPR: 94 case TRY_CATCH_EXPR: 95 case WITH_CLEANUP_EXPR: 96 case REALPART_EXPR: 97 case IMAGPART_EXPR: 98 return lvalue_kind (TREE_OPERAND (ref, 0)); 99 100 case COMPONENT_REF: 101 op1_lvalue_kind = lvalue_kind (TREE_OPERAND (ref, 0)); 102 /* Look at the member designator. */ 103 if (!op1_lvalue_kind) 104 ; 105 else if (is_overloaded_fn (TREE_OPERAND (ref, 1))) 106 /* The "field" can be a FUNCTION_DECL or an OVERLOAD in some 107 situations. If we're seeing a COMPONENT_REF, it's a non-static 108 member, so it isn't an lvalue. */ 109 op1_lvalue_kind = clk_none; 110 else if (TREE_CODE (TREE_OPERAND (ref, 1)) != FIELD_DECL) 111 /* This can be IDENTIFIER_NODE in a template. */; 112 else if (DECL_C_BIT_FIELD (TREE_OPERAND (ref, 1))) 113 { 114 /* Clear the ordinary bit. If this object was a class 115 rvalue we want to preserve that information. */ 116 op1_lvalue_kind &= ~clk_ordinary; 117 /* The lvalue is for a bitfield. */ 118 op1_lvalue_kind |= clk_bitfield; 119 } 120 else if (DECL_PACKED (TREE_OPERAND (ref, 1))) 121 op1_lvalue_kind |= clk_packed; 122 123 return op1_lvalue_kind; 124 125 case STRING_CST: 126 case COMPOUND_LITERAL_EXPR: 127 return clk_ordinary; 128 129 case CONST_DECL: 130 /* CONST_DECL without TREE_STATIC are enumeration values and 131 thus not lvalues. With TREE_STATIC they are used by ObjC++ 132 in objc_build_string_object and need to be considered as 133 lvalues. */ 134 if (! TREE_STATIC (ref)) 135 return clk_none; 136 case VAR_DECL: 137 if (TREE_READONLY (ref) && ! TREE_STATIC (ref) 138 && DECL_LANG_SPECIFIC (ref) 139 && DECL_IN_AGGR_P (ref)) 140 return clk_none; 141 case INDIRECT_REF: 142 case ARROW_EXPR: 143 case ARRAY_REF: 144 case PARM_DECL: 145 case RESULT_DECL: 146 if (TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE) 147 return clk_ordinary; 148 break; 149 150 /* A scope ref in a template, left as SCOPE_REF to support later 151 access checking. */ 152 case SCOPE_REF: 153 { 154 tree op = TREE_OPERAND (ref, 1); 155 /* The member must be an lvalue; assume it isn't a bit-field. */ 156 if (TREE_CODE (op) == IDENTIFIER_NODE) 157 return clk_ordinary; 158 gcc_assert (!type_dependent_expression_p (CONST_CAST_TREE (ref))); 159 return lvalue_kind (op); 160 } 161 162 case MAX_EXPR: 163 case MIN_EXPR: 164 /* Disallow <? and >? as lvalues if either argument side-effects. */ 165 if (TREE_SIDE_EFFECTS (TREE_OPERAND (ref, 0)) 166 || TREE_SIDE_EFFECTS (TREE_OPERAND (ref, 1))) 167 return clk_none; 168 op1_lvalue_kind = lvalue_kind (TREE_OPERAND (ref, 0)); 169 op2_lvalue_kind = lvalue_kind (TREE_OPERAND (ref, 1)); 170 break; 171 172 case COND_EXPR: 173 op1_lvalue_kind = lvalue_kind (TREE_OPERAND (ref, 1) 174 ? TREE_OPERAND (ref, 1) 175 : TREE_OPERAND (ref, 0)); 176 op2_lvalue_kind = lvalue_kind (TREE_OPERAND (ref, 2)); 177 break; 178 179 case MODIFY_EXPR: 180 case TYPEID_EXPR: 181 return clk_ordinary; 182 183 case COMPOUND_EXPR: 184 return lvalue_kind (TREE_OPERAND (ref, 1)); 185 186 case TARGET_EXPR: 187 return clk_class; 188 189 case VA_ARG_EXPR: 190 return (CLASS_TYPE_P (TREE_TYPE (ref)) ? clk_class : clk_none); 191 192 case CALL_EXPR: 193 /* We can see calls outside of TARGET_EXPR in templates. */ 194 if (CLASS_TYPE_P (TREE_TYPE (ref))) 195 return clk_class; 196 return clk_none; 197 198 case FUNCTION_DECL: 199 /* All functions (except non-static-member functions) are 200 lvalues. */ 201 return (DECL_NONSTATIC_MEMBER_FUNCTION_P (ref) 202 ? clk_none : clk_ordinary); 203 204 case BASELINK: 205 /* We now represent a reference to a single static member function 206 with a BASELINK. */ 207 /* This CONST_CAST is okay because BASELINK_FUNCTIONS returns 208 its argument unmodified and we assign it to a const_tree. */ 209 return lvalue_kind (BASELINK_FUNCTIONS (CONST_CAST_TREE (ref))); 210 211 case NON_DEPENDENT_EXPR: 212 /* We just return clk_ordinary for NON_DEPENDENT_EXPR in C++98, but 213 in C++11 lvalues don't bind to rvalue references, so we need to 214 work harder to avoid bogus errors (c++/44870). */ 215 if (cxx_dialect < cxx0x) 216 return clk_ordinary; 217 else 218 return lvalue_kind (TREE_OPERAND (ref, 0)); 219 220 default: 221 if (!TREE_TYPE (ref)) 222 return clk_none; 223 if (CLASS_TYPE_P (TREE_TYPE (ref))) 224 return clk_class; 225 break; 226 } 227 228 /* If one operand is not an lvalue at all, then this expression is 229 not an lvalue. */ 230 if (!op1_lvalue_kind || !op2_lvalue_kind) 231 return clk_none; 232 233 /* Otherwise, it's an lvalue, and it has all the odd properties 234 contributed by either operand. */ 235 op1_lvalue_kind = op1_lvalue_kind | op2_lvalue_kind; 236 /* It's not an ordinary lvalue if it involves any other kind. */ 237 if ((op1_lvalue_kind & ~clk_ordinary) != clk_none) 238 op1_lvalue_kind &= ~clk_ordinary; 239 /* It can't be both a pseudo-lvalue and a non-addressable lvalue. 240 A COND_EXPR of those should be wrapped in a TARGET_EXPR. */ 241 if ((op1_lvalue_kind & (clk_rvalueref|clk_class)) 242 && (op1_lvalue_kind & (clk_bitfield|clk_packed))) 243 op1_lvalue_kind = clk_none; 244 return op1_lvalue_kind; 245 } 246 247 /* Returns the kind of lvalue that REF is, in the sense of 248 [basic.lval]. This function should really be named lvalue_p; it 249 computes the C++ definition of lvalue. */ 250 251 cp_lvalue_kind 252 real_lvalue_p (const_tree ref) 253 { 254 cp_lvalue_kind kind = lvalue_kind (ref); 255 if (kind & (clk_rvalueref|clk_class)) 256 return clk_none; 257 else 258 return kind; 259 } 260 261 /* This differs from real_lvalue_p in that class rvalues are considered 262 lvalues. */ 263 264 bool 265 lvalue_p (const_tree ref) 266 { 267 return (lvalue_kind (ref) != clk_none); 268 } 269 270 /* This differs from real_lvalue_p in that rvalues formed by dereferencing 271 rvalue references are considered rvalues. */ 272 273 bool 274 lvalue_or_rvalue_with_address_p (const_tree ref) 275 { 276 cp_lvalue_kind kind = lvalue_kind (ref); 277 if (kind & clk_class) 278 return false; 279 else 280 return (kind != clk_none); 281 } 282 283 /* Test whether DECL is a builtin that may appear in a 284 constant-expression. */ 285 286 bool 287 builtin_valid_in_constant_expr_p (const_tree decl) 288 { 289 /* At present BUILT_IN_CONSTANT_P is the only builtin we're allowing 290 in constant-expressions. We may want to add other builtins later. */ 291 return DECL_IS_BUILTIN_CONSTANT_P (decl); 292 } 293 294 /* Build a TARGET_EXPR, initializing the DECL with the VALUE. */ 295 296 static tree 297 build_target_expr (tree decl, tree value, tsubst_flags_t complain) 298 { 299 tree t; 300 tree type = TREE_TYPE (decl); 301 302 #ifdef ENABLE_CHECKING 303 gcc_assert (VOID_TYPE_P (TREE_TYPE (value)) 304 || TREE_TYPE (decl) == TREE_TYPE (value) 305 /* On ARM ctors return 'this'. */ 306 || (TREE_CODE (TREE_TYPE (value)) == POINTER_TYPE 307 && TREE_CODE (value) == CALL_EXPR) 308 || useless_type_conversion_p (TREE_TYPE (decl), 309 TREE_TYPE (value))); 310 #endif 311 312 t = cxx_maybe_build_cleanup (decl, complain); 313 if (t == error_mark_node) 314 return error_mark_node; 315 t = build4 (TARGET_EXPR, type, decl, value, t, NULL_TREE); 316 /* We always set TREE_SIDE_EFFECTS so that expand_expr does not 317 ignore the TARGET_EXPR. If there really turn out to be no 318 side-effects, then the optimizer should be able to get rid of 319 whatever code is generated anyhow. */ 320 TREE_SIDE_EFFECTS (t) = 1; 321 if (literal_type_p (type)) 322 TREE_CONSTANT (t) = TREE_CONSTANT (value); 323 324 return t; 325 } 326 327 /* Return an undeclared local temporary of type TYPE for use in building a 328 TARGET_EXPR. */ 329 330 static tree 331 build_local_temp (tree type) 332 { 333 tree slot = build_decl (input_location, 334 VAR_DECL, NULL_TREE, type); 335 DECL_ARTIFICIAL (slot) = 1; 336 DECL_IGNORED_P (slot) = 1; 337 DECL_CONTEXT (slot) = current_function_decl; 338 layout_decl (slot, 0); 339 return slot; 340 } 341 342 /* Set various status flags when building an AGGR_INIT_EXPR object T. */ 343 344 static void 345 process_aggr_init_operands (tree t) 346 { 347 bool side_effects; 348 349 side_effects = TREE_SIDE_EFFECTS (t); 350 if (!side_effects) 351 { 352 int i, n; 353 n = TREE_OPERAND_LENGTH (t); 354 for (i = 1; i < n; i++) 355 { 356 tree op = TREE_OPERAND (t, i); 357 if (op && TREE_SIDE_EFFECTS (op)) 358 { 359 side_effects = 1; 360 break; 361 } 362 } 363 } 364 TREE_SIDE_EFFECTS (t) = side_effects; 365 } 366 367 /* Build an AGGR_INIT_EXPR of class tcc_vl_exp with the indicated RETURN_TYPE, 368 FN, and SLOT. NARGS is the number of call arguments which are specified 369 as a tree array ARGS. */ 370 371 static tree 372 build_aggr_init_array (tree return_type, tree fn, tree slot, int nargs, 373 tree *args) 374 { 375 tree t; 376 int i; 377 378 t = build_vl_exp (AGGR_INIT_EXPR, nargs + 3); 379 TREE_TYPE (t) = return_type; 380 AGGR_INIT_EXPR_FN (t) = fn; 381 AGGR_INIT_EXPR_SLOT (t) = slot; 382 for (i = 0; i < nargs; i++) 383 AGGR_INIT_EXPR_ARG (t, i) = args[i]; 384 process_aggr_init_operands (t); 385 return t; 386 } 387 388 /* INIT is a CALL_EXPR or AGGR_INIT_EXPR which needs info about its 389 target. TYPE is the type to be initialized. 390 391 Build an AGGR_INIT_EXPR to represent the initialization. This function 392 differs from build_cplus_new in that an AGGR_INIT_EXPR can only be used 393 to initialize another object, whereas a TARGET_EXPR can either 394 initialize another object or create its own temporary object, and as a 395 result building up a TARGET_EXPR requires that the type's destructor be 396 callable. */ 397 398 tree 399 build_aggr_init_expr (tree type, tree init, tsubst_flags_t complain) 400 { 401 tree fn; 402 tree slot; 403 tree rval; 404 int is_ctor; 405 406 /* Make sure that we're not trying to create an instance of an 407 abstract class. */ 408 if (abstract_virtuals_error_sfinae (NULL_TREE, type, complain)) 409 return error_mark_node; 410 411 if (TREE_CODE (init) == CALL_EXPR) 412 fn = CALL_EXPR_FN (init); 413 else if (TREE_CODE (init) == AGGR_INIT_EXPR) 414 fn = AGGR_INIT_EXPR_FN (init); 415 else 416 return convert (type, init); 417 418 is_ctor = (TREE_CODE (fn) == ADDR_EXPR 419 && TREE_CODE (TREE_OPERAND (fn, 0)) == FUNCTION_DECL 420 && DECL_CONSTRUCTOR_P (TREE_OPERAND (fn, 0))); 421 422 /* We split the CALL_EXPR into its function and its arguments here. 423 Then, in expand_expr, we put them back together. The reason for 424 this is that this expression might be a default argument 425 expression. In that case, we need a new temporary every time the 426 expression is used. That's what break_out_target_exprs does; it 427 replaces every AGGR_INIT_EXPR with a copy that uses a fresh 428 temporary slot. Then, expand_expr builds up a call-expression 429 using the new slot. */ 430 431 /* If we don't need to use a constructor to create an object of this 432 type, don't mess with AGGR_INIT_EXPR. */ 433 if (is_ctor || TREE_ADDRESSABLE (type)) 434 { 435 slot = build_local_temp (type); 436 437 if (TREE_CODE(init) == CALL_EXPR) 438 rval = build_aggr_init_array (void_type_node, fn, slot, 439 call_expr_nargs (init), 440 CALL_EXPR_ARGP (init)); 441 else 442 rval = build_aggr_init_array (void_type_node, fn, slot, 443 aggr_init_expr_nargs (init), 444 AGGR_INIT_EXPR_ARGP (init)); 445 TREE_SIDE_EFFECTS (rval) = 1; 446 AGGR_INIT_VIA_CTOR_P (rval) = is_ctor; 447 TREE_NOTHROW (rval) = TREE_NOTHROW (init); 448 } 449 else 450 rval = init; 451 452 return rval; 453 } 454 455 /* INIT is a CALL_EXPR or AGGR_INIT_EXPR which needs info about its 456 target. TYPE is the type that this initialization should appear to 457 have. 458 459 Build an encapsulation of the initialization to perform 460 and return it so that it can be processed by language-independent 461 and language-specific expression expanders. */ 462 463 tree 464 build_cplus_new (tree type, tree init, tsubst_flags_t complain) 465 { 466 tree rval = build_aggr_init_expr (type, init, complain); 467 tree slot; 468 469 if (TREE_CODE (rval) == AGGR_INIT_EXPR) 470 slot = AGGR_INIT_EXPR_SLOT (rval); 471 else if (TREE_CODE (rval) == CALL_EXPR 472 || TREE_CODE (rval) == CONSTRUCTOR) 473 slot = build_local_temp (type); 474 else 475 return rval; 476 477 rval = build_target_expr (slot, rval, complain); 478 479 if (rval != error_mark_node) 480 TARGET_EXPR_IMPLICIT_P (rval) = 1; 481 482 return rval; 483 } 484 485 /* Subroutine of build_vec_init_expr: Build up a single element 486 intialization as a proxy for the full array initialization to get things 487 marked as used and any appropriate diagnostics. 488 489 Since we're deferring building the actual constructor calls until 490 gimplification time, we need to build one now and throw it away so 491 that the relevant constructor gets mark_used before cgraph decides 492 what functions are needed. Here we assume that init is either 493 NULL_TREE, void_type_node (indicating value-initialization), or 494 another array to copy. */ 495 496 static tree 497 build_vec_init_elt (tree type, tree init, tsubst_flags_t complain) 498 { 499 tree inner_type = strip_array_types (type); 500 VEC(tree,gc) *argvec; 501 502 if (integer_zerop (array_type_nelts_total (type)) 503 || !CLASS_TYPE_P (inner_type)) 504 /* No interesting initialization to do. */ 505 return integer_zero_node; 506 else if (init == void_type_node) 507 return build_value_init (inner_type, complain); 508 509 gcc_assert (init == NULL_TREE 510 || (same_type_ignoring_top_level_qualifiers_p 511 (type, TREE_TYPE (init)))); 512 513 argvec = make_tree_vector (); 514 if (init) 515 { 516 tree dummy = build_dummy_object (inner_type); 517 if (!real_lvalue_p (init)) 518 dummy = move (dummy); 519 VEC_quick_push (tree, argvec, dummy); 520 } 521 init = build_special_member_call (NULL_TREE, complete_ctor_identifier, 522 &argvec, inner_type, LOOKUP_NORMAL, 523 complain); 524 release_tree_vector (argvec); 525 526 /* For a trivial constructor, build_over_call creates a TARGET_EXPR. But 527 we don't want one here because we aren't creating a temporary. */ 528 if (TREE_CODE (init) == TARGET_EXPR) 529 init = TARGET_EXPR_INITIAL (init); 530 531 return init; 532 } 533 534 /* Return a TARGET_EXPR which expresses the initialization of an array to 535 be named later, either default-initialization or copy-initialization 536 from another array of the same type. */ 537 538 tree 539 build_vec_init_expr (tree type, tree init, tsubst_flags_t complain) 540 { 541 tree slot; 542 bool value_init = false; 543 tree elt_init = build_vec_init_elt (type, init, complain); 544 545 if (init == void_type_node) 546 { 547 value_init = true; 548 init = NULL_TREE; 549 } 550 551 slot = build_local_temp (type); 552 init = build2 (VEC_INIT_EXPR, type, slot, init); 553 TREE_SIDE_EFFECTS (init) = true; 554 SET_EXPR_LOCATION (init, input_location); 555 556 if (cxx_dialect >= cxx0x 557 && potential_constant_expression (elt_init)) 558 VEC_INIT_EXPR_IS_CONSTEXPR (init) = true; 559 VEC_INIT_EXPR_VALUE_INIT (init) = value_init; 560 561 return init; 562 } 563 564 /* Give a helpful diagnostic for a non-constexpr VEC_INIT_EXPR in a context 565 that requires a constant expression. */ 566 567 void 568 diagnose_non_constexpr_vec_init (tree expr) 569 { 570 tree type = TREE_TYPE (VEC_INIT_EXPR_SLOT (expr)); 571 tree init, elt_init; 572 if (VEC_INIT_EXPR_VALUE_INIT (expr)) 573 init = void_type_node; 574 else 575 init = VEC_INIT_EXPR_INIT (expr); 576 577 elt_init = build_vec_init_elt (type, init, tf_warning_or_error); 578 require_potential_constant_expression (elt_init); 579 } 580 581 tree 582 build_array_copy (tree init) 583 { 584 return build_vec_init_expr (TREE_TYPE (init), init, tf_warning_or_error); 585 } 586 587 /* Build a TARGET_EXPR using INIT to initialize a new temporary of the 588 indicated TYPE. */ 589 590 tree 591 build_target_expr_with_type (tree init, tree type, tsubst_flags_t complain) 592 { 593 gcc_assert (!VOID_TYPE_P (type)); 594 595 if (TREE_CODE (init) == TARGET_EXPR 596 || init == error_mark_node) 597 return init; 598 else if (CLASS_TYPE_P (type) && type_has_nontrivial_copy_init (type) 599 && !VOID_TYPE_P (TREE_TYPE (init)) 600 && TREE_CODE (init) != COND_EXPR 601 && TREE_CODE (init) != CONSTRUCTOR 602 && TREE_CODE (init) != VA_ARG_EXPR) 603 /* We need to build up a copy constructor call. A void initializer 604 means we're being called from bot_manip. COND_EXPR is a special 605 case because we already have copies on the arms and we don't want 606 another one here. A CONSTRUCTOR is aggregate initialization, which 607 is handled separately. A VA_ARG_EXPR is magic creation of an 608 aggregate; there's no additional work to be done. */ 609 return force_rvalue (init, complain); 610 611 return force_target_expr (type, init, complain); 612 } 613 614 /* Like the above function, but without the checking. This function should 615 only be used by code which is deliberately trying to subvert the type 616 system, such as call_builtin_trap. Or build_over_call, to avoid 617 infinite recursion. */ 618 619 tree 620 force_target_expr (tree type, tree init, tsubst_flags_t complain) 621 { 622 tree slot; 623 624 gcc_assert (!VOID_TYPE_P (type)); 625 626 slot = build_local_temp (type); 627 return build_target_expr (slot, init, complain); 628 } 629 630 /* Like build_target_expr_with_type, but use the type of INIT. */ 631 632 tree 633 get_target_expr_sfinae (tree init, tsubst_flags_t complain) 634 { 635 if (TREE_CODE (init) == AGGR_INIT_EXPR) 636 return build_target_expr (AGGR_INIT_EXPR_SLOT (init), init, complain); 637 else if (TREE_CODE (init) == VEC_INIT_EXPR) 638 return build_target_expr (VEC_INIT_EXPR_SLOT (init), init, complain); 639 else 640 return build_target_expr_with_type (init, TREE_TYPE (init), complain); 641 } 642 643 tree 644 get_target_expr (tree init) 645 { 646 return get_target_expr_sfinae (init, tf_warning_or_error); 647 } 648 649 /* If EXPR is a bitfield reference, convert it to the declared type of 650 the bitfield, and return the resulting expression. Otherwise, 651 return EXPR itself. */ 652 653 tree 654 convert_bitfield_to_declared_type (tree expr) 655 { 656 tree bitfield_type; 657 658 bitfield_type = is_bitfield_expr_with_lowered_type (expr); 659 if (bitfield_type) 660 expr = convert_to_integer (TYPE_MAIN_VARIANT (bitfield_type), 661 expr); 662 return expr; 663 } 664 665 /* EXPR is being used in an rvalue context. Return a version of EXPR 666 that is marked as an rvalue. */ 667 668 tree 669 rvalue (tree expr) 670 { 671 tree type; 672 673 if (error_operand_p (expr)) 674 return expr; 675 676 expr = mark_rvalue_use (expr); 677 678 /* [basic.lval] 679 680 Non-class rvalues always have cv-unqualified types. */ 681 type = TREE_TYPE (expr); 682 if (!CLASS_TYPE_P (type) && cv_qualified_p (type)) 683 type = cv_unqualified (type); 684 685 /* We need to do this for rvalue refs as well to get the right answer 686 from decltype; see c++/36628. */ 687 if (!processing_template_decl && lvalue_or_rvalue_with_address_p (expr)) 688 expr = build1 (NON_LVALUE_EXPR, type, expr); 689 else if (type != TREE_TYPE (expr)) 690 expr = build_nop (type, expr); 691 692 return expr; 693 } 694 695 696 /* Hash an ARRAY_TYPE. K is really of type `tree'. */ 697 698 static hashval_t 699 cplus_array_hash (const void* k) 700 { 701 hashval_t hash; 702 const_tree const t = (const_tree) k; 703 704 hash = TYPE_UID (TREE_TYPE (t)); 705 if (TYPE_DOMAIN (t)) 706 hash ^= TYPE_UID (TYPE_DOMAIN (t)); 707 return hash; 708 } 709 710 typedef struct cplus_array_info { 711 tree type; 712 tree domain; 713 } cplus_array_info; 714 715 /* Compare two ARRAY_TYPEs. K1 is really of type `tree', K2 is really 716 of type `cplus_array_info*'. */ 717 718 static int 719 cplus_array_compare (const void * k1, const void * k2) 720 { 721 const_tree const t1 = (const_tree) k1; 722 const cplus_array_info *const t2 = (const cplus_array_info*) k2; 723 724 return (TREE_TYPE (t1) == t2->type && TYPE_DOMAIN (t1) == t2->domain); 725 } 726 727 /* Hash table containing dependent array types, which are unsuitable for 728 the language-independent type hash table. */ 729 static GTY ((param_is (union tree_node))) htab_t cplus_array_htab; 730 731 /* Like build_array_type, but handle special C++ semantics. */ 732 733 tree 734 build_cplus_array_type (tree elt_type, tree index_type) 735 { 736 tree t; 737 738 if (elt_type == error_mark_node || index_type == error_mark_node) 739 return error_mark_node; 740 741 if (processing_template_decl 742 && (dependent_type_p (elt_type) 743 || (index_type && !TREE_CONSTANT (TYPE_MAX_VALUE (index_type))))) 744 { 745 void **e; 746 cplus_array_info cai; 747 hashval_t hash; 748 749 if (cplus_array_htab == NULL) 750 cplus_array_htab = htab_create_ggc (61, &cplus_array_hash, 751 &cplus_array_compare, NULL); 752 753 hash = TYPE_UID (elt_type); 754 if (index_type) 755 hash ^= TYPE_UID (index_type); 756 cai.type = elt_type; 757 cai.domain = index_type; 758 759 e = htab_find_slot_with_hash (cplus_array_htab, &cai, hash, INSERT); 760 if (*e) 761 /* We have found the type: we're done. */ 762 return (tree) *e; 763 else 764 { 765 /* Build a new array type. */ 766 t = cxx_make_type (ARRAY_TYPE); 767 TREE_TYPE (t) = elt_type; 768 TYPE_DOMAIN (t) = index_type; 769 770 /* Store it in the hash table. */ 771 *e = t; 772 773 /* Set the canonical type for this new node. */ 774 if (TYPE_STRUCTURAL_EQUALITY_P (elt_type) 775 || (index_type && TYPE_STRUCTURAL_EQUALITY_P (index_type))) 776 SET_TYPE_STRUCTURAL_EQUALITY (t); 777 else if (TYPE_CANONICAL (elt_type) != elt_type 778 || (index_type 779 && TYPE_CANONICAL (index_type) != index_type)) 780 TYPE_CANONICAL (t) 781 = build_cplus_array_type 782 (TYPE_CANONICAL (elt_type), 783 index_type ? TYPE_CANONICAL (index_type) : index_type); 784 else 785 TYPE_CANONICAL (t) = t; 786 } 787 } 788 else 789 { 790 if (!TYPE_STRUCTURAL_EQUALITY_P (elt_type) 791 && !(index_type && TYPE_STRUCTURAL_EQUALITY_P (index_type)) 792 && (TYPE_CANONICAL (elt_type) != elt_type 793 || (index_type && TYPE_CANONICAL (index_type) != index_type))) 794 /* Make sure that the canonical type is on the appropriate 795 variants list. */ 796 build_cplus_array_type 797 (TYPE_CANONICAL (elt_type), 798 index_type ? TYPE_CANONICAL (index_type) : index_type); 799 t = build_array_type (elt_type, index_type); 800 } 801 802 /* We want TYPE_MAIN_VARIANT of an array to strip cv-quals from the 803 element type as well, so fix it up if needed. */ 804 if (elt_type != TYPE_MAIN_VARIANT (elt_type)) 805 { 806 tree m = build_cplus_array_type (TYPE_MAIN_VARIANT (elt_type), 807 index_type); 808 809 if (TYPE_MAIN_VARIANT (t) != m) 810 { 811 TYPE_MAIN_VARIANT (t) = m; 812 TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (m); 813 TYPE_NEXT_VARIANT (m) = t; 814 } 815 } 816 817 /* Push these needs up so that initialization takes place 818 more easily. */ 819 TYPE_NEEDS_CONSTRUCTING (t) 820 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (elt_type)); 821 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) 822 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (elt_type)); 823 return t; 824 } 825 826 /* Return an ARRAY_TYPE with element type ELT and length N. */ 827 828 tree 829 build_array_of_n_type (tree elt, int n) 830 { 831 return build_cplus_array_type (elt, build_index_type (size_int (n - 1))); 832 } 833 834 /* Return a reference type node referring to TO_TYPE. If RVAL is 835 true, return an rvalue reference type, otherwise return an lvalue 836 reference type. If a type node exists, reuse it, otherwise create 837 a new one. */ 838 tree 839 cp_build_reference_type (tree to_type, bool rval) 840 { 841 tree lvalue_ref, t; 842 lvalue_ref = build_reference_type (to_type); 843 if (!rval) 844 return lvalue_ref; 845 846 /* This code to create rvalue reference types is based on and tied 847 to the code creating lvalue reference types in the middle-end 848 functions build_reference_type_for_mode and build_reference_type. 849 850 It works by putting the rvalue reference type nodes after the 851 lvalue reference nodes in the TYPE_NEXT_REF_TO linked list, so 852 they will effectively be ignored by the middle end. */ 853 854 for (t = lvalue_ref; (t = TYPE_NEXT_REF_TO (t)); ) 855 if (TYPE_REF_IS_RVALUE (t)) 856 return t; 857 858 t = build_distinct_type_copy (lvalue_ref); 859 860 TYPE_REF_IS_RVALUE (t) = true; 861 TYPE_NEXT_REF_TO (t) = TYPE_NEXT_REF_TO (lvalue_ref); 862 TYPE_NEXT_REF_TO (lvalue_ref) = t; 863 864 if (TYPE_STRUCTURAL_EQUALITY_P (to_type)) 865 SET_TYPE_STRUCTURAL_EQUALITY (t); 866 else if (TYPE_CANONICAL (to_type) != to_type) 867 TYPE_CANONICAL (t) 868 = cp_build_reference_type (TYPE_CANONICAL (to_type), rval); 869 else 870 TYPE_CANONICAL (t) = t; 871 872 layout_type (t); 873 874 return t; 875 876 } 877 878 /* Returns EXPR cast to rvalue reference type, like std::move. */ 879 880 tree 881 move (tree expr) 882 { 883 tree type = TREE_TYPE (expr); 884 gcc_assert (TREE_CODE (type) != REFERENCE_TYPE); 885 type = cp_build_reference_type (type, /*rval*/true); 886 return build_static_cast (type, expr, tf_warning_or_error); 887 } 888 889 /* Used by the C++ front end to build qualified array types. However, 890 the C version of this function does not properly maintain canonical 891 types (which are not used in C). */ 892 tree 893 c_build_qualified_type (tree type, int type_quals) 894 { 895 return cp_build_qualified_type (type, type_quals); 896 } 897 898 899 /* Make a variant of TYPE, qualified with the TYPE_QUALS. Handles 900 arrays correctly. In particular, if TYPE is an array of T's, and 901 TYPE_QUALS is non-empty, returns an array of qualified T's. 902 903 FLAGS determines how to deal with ill-formed qualifications. If 904 tf_ignore_bad_quals is set, then bad qualifications are dropped 905 (this is permitted if TYPE was introduced via a typedef or template 906 type parameter). If bad qualifications are dropped and tf_warning 907 is set, then a warning is issued for non-const qualifications. If 908 tf_ignore_bad_quals is not set and tf_error is not set, we 909 return error_mark_node. Otherwise, we issue an error, and ignore 910 the qualifications. 911 912 Qualification of a reference type is valid when the reference came 913 via a typedef or template type argument. [dcl.ref] No such 914 dispensation is provided for qualifying a function type. [dcl.fct] 915 DR 295 queries this and the proposed resolution brings it into line 916 with qualifying a reference. We implement the DR. We also behave 917 in a similar manner for restricting non-pointer types. */ 918 919 tree 920 cp_build_qualified_type_real (tree type, 921 int type_quals, 922 tsubst_flags_t complain) 923 { 924 tree result; 925 int bad_quals = TYPE_UNQUALIFIED; 926 927 if (type == error_mark_node) 928 return type; 929 930 if (type_quals == cp_type_quals (type)) 931 return type; 932 933 if (TREE_CODE (type) == ARRAY_TYPE) 934 { 935 /* In C++, the qualification really applies to the array element 936 type. Obtain the appropriately qualified element type. */ 937 tree t; 938 tree element_type 939 = cp_build_qualified_type_real (TREE_TYPE (type), 940 type_quals, 941 complain); 942 943 if (element_type == error_mark_node) 944 return error_mark_node; 945 946 /* See if we already have an identically qualified type. Tests 947 should be equivalent to those in check_qualified_type. */ 948 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t)) 949 if (TREE_TYPE (t) == element_type 950 && TYPE_NAME (t) == TYPE_NAME (type) 951 && TYPE_CONTEXT (t) == TYPE_CONTEXT (type) 952 && attribute_list_equal (TYPE_ATTRIBUTES (t), 953 TYPE_ATTRIBUTES (type))) 954 break; 955 956 if (!t) 957 { 958 t = build_cplus_array_type (element_type, TYPE_DOMAIN (type)); 959 960 /* Keep the typedef name. */ 961 if (TYPE_NAME (t) != TYPE_NAME (type)) 962 { 963 t = build_variant_type_copy (t); 964 TYPE_NAME (t) = TYPE_NAME (type); 965 } 966 } 967 968 /* Even if we already had this variant, we update 969 TYPE_NEEDS_CONSTRUCTING and TYPE_HAS_NONTRIVIAL_DESTRUCTOR in case 970 they changed since the variant was originally created. 971 972 This seems hokey; if there is some way to use a previous 973 variant *without* coming through here, 974 TYPE_NEEDS_CONSTRUCTING will never be updated. */ 975 TYPE_NEEDS_CONSTRUCTING (t) 976 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (element_type)); 977 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) 978 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (element_type)); 979 return t; 980 } 981 else if (TYPE_PTRMEMFUNC_P (type)) 982 { 983 /* For a pointer-to-member type, we can't just return a 984 cv-qualified version of the RECORD_TYPE. If we do, we 985 haven't changed the field that contains the actual pointer to 986 a method, and so TYPE_PTRMEMFUNC_FN_TYPE will be wrong. */ 987 tree t; 988 989 t = TYPE_PTRMEMFUNC_FN_TYPE (type); 990 t = cp_build_qualified_type_real (t, type_quals, complain); 991 return build_ptrmemfunc_type (t); 992 } 993 else if (TREE_CODE (type) == TYPE_PACK_EXPANSION) 994 { 995 tree t = PACK_EXPANSION_PATTERN (type); 996 997 t = cp_build_qualified_type_real (t, type_quals, complain); 998 return make_pack_expansion (t); 999 } 1000 1001 /* A reference or method type shall not be cv-qualified. 1002 [dcl.ref], [dcl.fct]. This used to be an error, but as of DR 295 1003 (in CD1) we always ignore extra cv-quals on functions. */ 1004 if (type_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE) 1005 && (TREE_CODE (type) == REFERENCE_TYPE 1006 || TREE_CODE (type) == FUNCTION_TYPE 1007 || TREE_CODE (type) == METHOD_TYPE)) 1008 { 1009 if (TREE_CODE (type) == REFERENCE_TYPE) 1010 bad_quals |= type_quals & (TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE); 1011 type_quals &= ~(TYPE_QUAL_CONST | TYPE_QUAL_VOLATILE); 1012 } 1013 1014 /* But preserve any function-cv-quals on a FUNCTION_TYPE. */ 1015 if (TREE_CODE (type) == FUNCTION_TYPE) 1016 type_quals |= type_memfn_quals (type); 1017 1018 /* A restrict-qualified type must be a pointer (or reference) 1019 to object or incomplete type. */ 1020 if ((type_quals & TYPE_QUAL_RESTRICT) 1021 && TREE_CODE (type) != TEMPLATE_TYPE_PARM 1022 && TREE_CODE (type) != TYPENAME_TYPE 1023 && !POINTER_TYPE_P (type)) 1024 { 1025 bad_quals |= TYPE_QUAL_RESTRICT; 1026 type_quals &= ~TYPE_QUAL_RESTRICT; 1027 } 1028 1029 if (bad_quals == TYPE_UNQUALIFIED 1030 || (complain & tf_ignore_bad_quals)) 1031 /*OK*/; 1032 else if (!(complain & tf_error)) 1033 return error_mark_node; 1034 else 1035 { 1036 tree bad_type = build_qualified_type (ptr_type_node, bad_quals); 1037 error ("%qV qualifiers cannot be applied to %qT", 1038 bad_type, type); 1039 } 1040 1041 /* Retrieve (or create) the appropriately qualified variant. */ 1042 result = build_qualified_type (type, type_quals); 1043 1044 /* If this was a pointer-to-method type, and we just made a copy, 1045 then we need to unshare the record that holds the cached 1046 pointer-to-member-function type, because these will be distinct 1047 between the unqualified and qualified types. */ 1048 if (result != type 1049 && TREE_CODE (type) == POINTER_TYPE 1050 && TREE_CODE (TREE_TYPE (type)) == METHOD_TYPE 1051 && TYPE_LANG_SPECIFIC (result) == TYPE_LANG_SPECIFIC (type)) 1052 TYPE_LANG_SPECIFIC (result) = NULL; 1053 1054 /* We may also have ended up building a new copy of the canonical 1055 type of a pointer-to-method type, which could have the same 1056 sharing problem described above. */ 1057 if (TYPE_CANONICAL (result) != TYPE_CANONICAL (type) 1058 && TREE_CODE (type) == POINTER_TYPE 1059 && TREE_CODE (TREE_TYPE (type)) == METHOD_TYPE 1060 && (TYPE_LANG_SPECIFIC (TYPE_CANONICAL (result)) 1061 == TYPE_LANG_SPECIFIC (TYPE_CANONICAL (type)))) 1062 TYPE_LANG_SPECIFIC (TYPE_CANONICAL (result)) = NULL; 1063 1064 return result; 1065 } 1066 1067 /* Return TYPE with const and volatile removed. */ 1068 1069 tree 1070 cv_unqualified (tree type) 1071 { 1072 int quals; 1073 1074 if (type == error_mark_node) 1075 return type; 1076 1077 quals = cp_type_quals (type); 1078 quals &= ~(TYPE_QUAL_CONST|TYPE_QUAL_VOLATILE); 1079 return cp_build_qualified_type (type, quals); 1080 } 1081 1082 /* Builds a qualified variant of T that is not a typedef variant. 1083 E.g. consider the following declarations: 1084 typedef const int ConstInt; 1085 typedef ConstInt* PtrConstInt; 1086 If T is PtrConstInt, this function returns a type representing 1087 const int*. 1088 In other words, if T is a typedef, the function returns the underlying type. 1089 The cv-qualification and attributes of the type returned match the 1090 input type. 1091 They will always be compatible types. 1092 The returned type is built so that all of its subtypes 1093 recursively have their typedefs stripped as well. 1094 1095 This is different from just returning TYPE_CANONICAL (T) 1096 Because of several reasons: 1097 * If T is a type that needs structural equality 1098 its TYPE_CANONICAL (T) will be NULL. 1099 * TYPE_CANONICAL (T) desn't carry type attributes 1100 and looses template parameter names. */ 1101 1102 tree 1103 strip_typedefs (tree t) 1104 { 1105 tree result = NULL, type = NULL, t0 = NULL; 1106 1107 if (!t || t == error_mark_node || t == TYPE_CANONICAL (t)) 1108 return t; 1109 1110 gcc_assert (TYPE_P (t)); 1111 1112 switch (TREE_CODE (t)) 1113 { 1114 case POINTER_TYPE: 1115 type = strip_typedefs (TREE_TYPE (t)); 1116 result = build_pointer_type (type); 1117 break; 1118 case REFERENCE_TYPE: 1119 type = strip_typedefs (TREE_TYPE (t)); 1120 result = cp_build_reference_type (type, TYPE_REF_IS_RVALUE (t)); 1121 break; 1122 case OFFSET_TYPE: 1123 t0 = strip_typedefs (TYPE_OFFSET_BASETYPE (t)); 1124 type = strip_typedefs (TREE_TYPE (t)); 1125 result = build_offset_type (t0, type); 1126 break; 1127 case RECORD_TYPE: 1128 if (TYPE_PTRMEMFUNC_P (t)) 1129 { 1130 t0 = strip_typedefs (TYPE_PTRMEMFUNC_FN_TYPE (t)); 1131 result = build_ptrmemfunc_type (t0); 1132 } 1133 break; 1134 case ARRAY_TYPE: 1135 type = strip_typedefs (TREE_TYPE (t)); 1136 t0 = strip_typedefs (TYPE_DOMAIN (t));; 1137 result = build_cplus_array_type (type, t0); 1138 break; 1139 case FUNCTION_TYPE: 1140 case METHOD_TYPE: 1141 { 1142 tree arg_types = NULL, arg_node, arg_type; 1143 for (arg_node = TYPE_ARG_TYPES (t); 1144 arg_node; 1145 arg_node = TREE_CHAIN (arg_node)) 1146 { 1147 if (arg_node == void_list_node) 1148 break; 1149 arg_type = strip_typedefs (TREE_VALUE (arg_node)); 1150 gcc_assert (arg_type); 1151 1152 arg_types = 1153 tree_cons (TREE_PURPOSE (arg_node), arg_type, arg_types); 1154 } 1155 1156 if (arg_types) 1157 arg_types = nreverse (arg_types); 1158 1159 /* A list of parameters not ending with an ellipsis 1160 must end with void_list_node. */ 1161 if (arg_node) 1162 arg_types = chainon (arg_types, void_list_node); 1163 1164 type = strip_typedefs (TREE_TYPE (t)); 1165 if (TREE_CODE (t) == METHOD_TYPE) 1166 { 1167 tree class_type = TREE_TYPE (TREE_VALUE (arg_types)); 1168 gcc_assert (class_type); 1169 result = 1170 build_method_type_directly (class_type, type, 1171 TREE_CHAIN (arg_types)); 1172 } 1173 else 1174 { 1175 result = build_function_type (type, 1176 arg_types); 1177 result = apply_memfn_quals (result, type_memfn_quals (t)); 1178 } 1179 1180 if (TYPE_RAISES_EXCEPTIONS (t)) 1181 result = build_exception_variant (result, 1182 TYPE_RAISES_EXCEPTIONS (t)); 1183 } 1184 break; 1185 case TYPENAME_TYPE: 1186 result = make_typename_type (strip_typedefs (TYPE_CONTEXT (t)), 1187 TYPENAME_TYPE_FULLNAME (t), 1188 typename_type, tf_none); 1189 break; 1190 default: 1191 break; 1192 } 1193 1194 if (!result) 1195 result = TYPE_MAIN_VARIANT (t); 1196 if (TYPE_USER_ALIGN (t) != TYPE_USER_ALIGN (result) 1197 || TYPE_ALIGN (t) != TYPE_ALIGN (result)) 1198 { 1199 gcc_assert (TYPE_USER_ALIGN (t)); 1200 if (TYPE_ALIGN (t) == TYPE_ALIGN (result)) 1201 result = build_variant_type_copy (result); 1202 else 1203 result = build_aligned_type (result, TYPE_ALIGN (t)); 1204 TYPE_USER_ALIGN (result) = true; 1205 } 1206 if (TYPE_ATTRIBUTES (t)) 1207 result = cp_build_type_attribute_variant (result, TYPE_ATTRIBUTES (t)); 1208 return cp_build_qualified_type (result, cp_type_quals (t)); 1209 } 1210 1211 /* Makes a copy of BINFO and TYPE, which is to be inherited into a 1212 graph dominated by T. If BINFO is NULL, TYPE is a dependent base, 1213 and we do a shallow copy. If BINFO is non-NULL, we do a deep copy. 1214 VIRT indicates whether TYPE is inherited virtually or not. 1215 IGO_PREV points at the previous binfo of the inheritance graph 1216 order chain. The newly copied binfo's TREE_CHAIN forms this 1217 ordering. 1218 1219 The CLASSTYPE_VBASECLASSES vector of T is constructed in the 1220 correct order. That is in the order the bases themselves should be 1221 constructed in. 1222 1223 The BINFO_INHERITANCE of a virtual base class points to the binfo 1224 of the most derived type. ??? We could probably change this so that 1225 BINFO_INHERITANCE becomes synonymous with BINFO_PRIMARY, and hence 1226 remove a field. They currently can only differ for primary virtual 1227 virtual bases. */ 1228 1229 tree 1230 copy_binfo (tree binfo, tree type, tree t, tree *igo_prev, int virt) 1231 { 1232 tree new_binfo; 1233 1234 if (virt) 1235 { 1236 /* See if we've already made this virtual base. */ 1237 new_binfo = binfo_for_vbase (type, t); 1238 if (new_binfo) 1239 return new_binfo; 1240 } 1241 1242 new_binfo = make_tree_binfo (binfo ? BINFO_N_BASE_BINFOS (binfo) : 0); 1243 BINFO_TYPE (new_binfo) = type; 1244 1245 /* Chain it into the inheritance graph. */ 1246 TREE_CHAIN (*igo_prev) = new_binfo; 1247 *igo_prev = new_binfo; 1248 1249 if (binfo && !BINFO_DEPENDENT_BASE_P (binfo)) 1250 { 1251 int ix; 1252 tree base_binfo; 1253 1254 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), type)); 1255 1256 BINFO_OFFSET (new_binfo) = BINFO_OFFSET (binfo); 1257 BINFO_VIRTUALS (new_binfo) = BINFO_VIRTUALS (binfo); 1258 1259 /* We do not need to copy the accesses, as they are read only. */ 1260 BINFO_BASE_ACCESSES (new_binfo) = BINFO_BASE_ACCESSES (binfo); 1261 1262 /* Recursively copy base binfos of BINFO. */ 1263 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++) 1264 { 1265 tree new_base_binfo; 1266 new_base_binfo = copy_binfo (base_binfo, BINFO_TYPE (base_binfo), 1267 t, igo_prev, 1268 BINFO_VIRTUAL_P (base_binfo)); 1269 1270 if (!BINFO_INHERITANCE_CHAIN (new_base_binfo)) 1271 BINFO_INHERITANCE_CHAIN (new_base_binfo) = new_binfo; 1272 BINFO_BASE_APPEND (new_binfo, new_base_binfo); 1273 } 1274 } 1275 else 1276 BINFO_DEPENDENT_BASE_P (new_binfo) = 1; 1277 1278 if (virt) 1279 { 1280 /* Push it onto the list after any virtual bases it contains 1281 will have been pushed. */ 1282 VEC_quick_push (tree, CLASSTYPE_VBASECLASSES (t), new_binfo); 1283 BINFO_VIRTUAL_P (new_binfo) = 1; 1284 BINFO_INHERITANCE_CHAIN (new_binfo) = TYPE_BINFO (t); 1285 } 1286 1287 return new_binfo; 1288 } 1289 1290 /* Hashing of lists so that we don't make duplicates. 1291 The entry point is `list_hash_canon'. */ 1292 1293 /* Now here is the hash table. When recording a list, it is added 1294 to the slot whose index is the hash code mod the table size. 1295 Note that the hash table is used for several kinds of lists. 1296 While all these live in the same table, they are completely independent, 1297 and the hash code is computed differently for each of these. */ 1298 1299 static GTY ((param_is (union tree_node))) htab_t list_hash_table; 1300 1301 struct list_proxy 1302 { 1303 tree purpose; 1304 tree value; 1305 tree chain; 1306 }; 1307 1308 /* Compare ENTRY (an entry in the hash table) with DATA (a list_proxy 1309 for a node we are thinking about adding). */ 1310 1311 static int 1312 list_hash_eq (const void* entry, const void* data) 1313 { 1314 const_tree const t = (const_tree) entry; 1315 const struct list_proxy *const proxy = (const struct list_proxy *) data; 1316 1317 return (TREE_VALUE (t) == proxy->value 1318 && TREE_PURPOSE (t) == proxy->purpose 1319 && TREE_CHAIN (t) == proxy->chain); 1320 } 1321 1322 /* Compute a hash code for a list (chain of TREE_LIST nodes 1323 with goodies in the TREE_PURPOSE, TREE_VALUE, and bits of the 1324 TREE_COMMON slots), by adding the hash codes of the individual entries. */ 1325 1326 static hashval_t 1327 list_hash_pieces (tree purpose, tree value, tree chain) 1328 { 1329 hashval_t hashcode = 0; 1330 1331 if (chain) 1332 hashcode += TREE_HASH (chain); 1333 1334 if (value) 1335 hashcode += TREE_HASH (value); 1336 else 1337 hashcode += 1007; 1338 if (purpose) 1339 hashcode += TREE_HASH (purpose); 1340 else 1341 hashcode += 1009; 1342 return hashcode; 1343 } 1344 1345 /* Hash an already existing TREE_LIST. */ 1346 1347 static hashval_t 1348 list_hash (const void* p) 1349 { 1350 const_tree const t = (const_tree) p; 1351 return list_hash_pieces (TREE_PURPOSE (t), 1352 TREE_VALUE (t), 1353 TREE_CHAIN (t)); 1354 } 1355 1356 /* Given list components PURPOSE, VALUE, AND CHAIN, return the canonical 1357 object for an identical list if one already exists. Otherwise, build a 1358 new one, and record it as the canonical object. */ 1359 1360 tree 1361 hash_tree_cons (tree purpose, tree value, tree chain) 1362 { 1363 int hashcode = 0; 1364 void **slot; 1365 struct list_proxy proxy; 1366 1367 /* Hash the list node. */ 1368 hashcode = list_hash_pieces (purpose, value, chain); 1369 /* Create a proxy for the TREE_LIST we would like to create. We 1370 don't actually create it so as to avoid creating garbage. */ 1371 proxy.purpose = purpose; 1372 proxy.value = value; 1373 proxy.chain = chain; 1374 /* See if it is already in the table. */ 1375 slot = htab_find_slot_with_hash (list_hash_table, &proxy, hashcode, 1376 INSERT); 1377 /* If not, create a new node. */ 1378 if (!*slot) 1379 *slot = tree_cons (purpose, value, chain); 1380 return (tree) *slot; 1381 } 1382 1383 /* Constructor for hashed lists. */ 1384 1385 tree 1386 hash_tree_chain (tree value, tree chain) 1387 { 1388 return hash_tree_cons (NULL_TREE, value, chain); 1389 } 1390 1391 void 1392 debug_binfo (tree elem) 1393 { 1394 HOST_WIDE_INT n; 1395 tree virtuals; 1396 1397 fprintf (stderr, "type \"%s\", offset = " HOST_WIDE_INT_PRINT_DEC 1398 "\nvtable type:\n", 1399 TYPE_NAME_STRING (BINFO_TYPE (elem)), 1400 TREE_INT_CST_LOW (BINFO_OFFSET (elem))); 1401 debug_tree (BINFO_TYPE (elem)); 1402 if (BINFO_VTABLE (elem)) 1403 fprintf (stderr, "vtable decl \"%s\"\n", 1404 IDENTIFIER_POINTER (DECL_NAME (get_vtbl_decl_for_binfo (elem)))); 1405 else 1406 fprintf (stderr, "no vtable decl yet\n"); 1407 fprintf (stderr, "virtuals:\n"); 1408 virtuals = BINFO_VIRTUALS (elem); 1409 n = 0; 1410 1411 while (virtuals) 1412 { 1413 tree fndecl = TREE_VALUE (virtuals); 1414 fprintf (stderr, "%s [%ld =? %ld]\n", 1415 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (fndecl)), 1416 (long) n, (long) TREE_INT_CST_LOW (DECL_VINDEX (fndecl))); 1417 ++n; 1418 virtuals = TREE_CHAIN (virtuals); 1419 } 1420 } 1421 1422 /* Build a representation for the qualified name SCOPE::NAME. TYPE is 1423 the type of the result expression, if known, or NULL_TREE if the 1424 resulting expression is type-dependent. If TEMPLATE_P is true, 1425 NAME is known to be a template because the user explicitly used the 1426 "template" keyword after the "::". 1427 1428 All SCOPE_REFs should be built by use of this function. */ 1429 1430 tree 1431 build_qualified_name (tree type, tree scope, tree name, bool template_p) 1432 { 1433 tree t; 1434 if (type == error_mark_node 1435 || scope == error_mark_node 1436 || name == error_mark_node) 1437 return error_mark_node; 1438 t = build2 (SCOPE_REF, type, scope, name); 1439 QUALIFIED_NAME_IS_TEMPLATE (t) = template_p; 1440 PTRMEM_OK_P (t) = true; 1441 if (type) 1442 t = convert_from_reference (t); 1443 return t; 1444 } 1445 1446 /* Returns nonzero if X is an expression for a (possibly overloaded) 1447 function. If "f" is a function or function template, "f", "c->f", 1448 "c.f", "C::f", and "f<int>" will all be considered possibly 1449 overloaded functions. Returns 2 if the function is actually 1450 overloaded, i.e., if it is impossible to know the type of the 1451 function without performing overload resolution. */ 1452 1453 int 1454 is_overloaded_fn (tree x) 1455 { 1456 /* A baselink is also considered an overloaded function. */ 1457 if (TREE_CODE (x) == OFFSET_REF 1458 || TREE_CODE (x) == COMPONENT_REF) 1459 x = TREE_OPERAND (x, 1); 1460 if (BASELINK_P (x)) 1461 x = BASELINK_FUNCTIONS (x); 1462 if (TREE_CODE (x) == TEMPLATE_ID_EXPR) 1463 x = TREE_OPERAND (x, 0); 1464 if (DECL_FUNCTION_TEMPLATE_P (OVL_CURRENT (x)) 1465 || (TREE_CODE (x) == OVERLOAD && OVL_CHAIN (x))) 1466 return 2; 1467 return (TREE_CODE (x) == FUNCTION_DECL 1468 || TREE_CODE (x) == OVERLOAD); 1469 } 1470 1471 /* X is the CALL_EXPR_FN of a CALL_EXPR. If X represents a dependent name 1472 (14.6.2), return the IDENTIFIER_NODE for that name. Otherwise, return 1473 NULL_TREE. */ 1474 1475 tree 1476 dependent_name (tree x) 1477 { 1478 if (TREE_CODE (x) == IDENTIFIER_NODE) 1479 return x; 1480 if (TREE_CODE (x) != COMPONENT_REF 1481 && TREE_CODE (x) != OFFSET_REF 1482 && TREE_CODE (x) != BASELINK 1483 && is_overloaded_fn (x)) 1484 return DECL_NAME (get_first_fn (x)); 1485 return NULL_TREE; 1486 } 1487 1488 /* Returns true iff X is an expression for an overloaded function 1489 whose type cannot be known without performing overload 1490 resolution. */ 1491 1492 bool 1493 really_overloaded_fn (tree x) 1494 { 1495 return is_overloaded_fn (x) == 2; 1496 } 1497 1498 tree 1499 get_fns (tree from) 1500 { 1501 gcc_assert (is_overloaded_fn (from)); 1502 /* A baselink is also considered an overloaded function. */ 1503 if (TREE_CODE (from) == OFFSET_REF 1504 || TREE_CODE (from) == COMPONENT_REF) 1505 from = TREE_OPERAND (from, 1); 1506 if (BASELINK_P (from)) 1507 from = BASELINK_FUNCTIONS (from); 1508 if (TREE_CODE (from) == TEMPLATE_ID_EXPR) 1509 from = TREE_OPERAND (from, 0); 1510 return from; 1511 } 1512 1513 tree 1514 get_first_fn (tree from) 1515 { 1516 return OVL_CURRENT (get_fns (from)); 1517 } 1518 1519 /* Return a new OVL node, concatenating it with the old one. */ 1520 1521 tree 1522 ovl_cons (tree decl, tree chain) 1523 { 1524 tree result = make_node (OVERLOAD); 1525 TREE_TYPE (result) = unknown_type_node; 1526 OVL_FUNCTION (result) = decl; 1527 TREE_CHAIN (result) = chain; 1528 1529 return result; 1530 } 1531 1532 /* Build a new overloaded function. If this is the first one, 1533 just return it; otherwise, ovl_cons the _DECLs */ 1534 1535 tree 1536 build_overload (tree decl, tree chain) 1537 { 1538 if (! chain && TREE_CODE (decl) != TEMPLATE_DECL) 1539 return decl; 1540 return ovl_cons (decl, chain); 1541 } 1542 1543 /* Return the scope where the overloaded functions OVL were found. */ 1544 1545 tree 1546 ovl_scope (tree ovl) 1547 { 1548 if (TREE_CODE (ovl) == OFFSET_REF 1549 || TREE_CODE (ovl) == COMPONENT_REF) 1550 ovl = TREE_OPERAND (ovl, 1); 1551 if (TREE_CODE (ovl) == BASELINK) 1552 return BINFO_TYPE (BASELINK_BINFO (ovl)); 1553 if (TREE_CODE (ovl) == TEMPLATE_ID_EXPR) 1554 ovl = TREE_OPERAND (ovl, 0); 1555 /* Skip using-declarations. */ 1556 while (TREE_CODE (ovl) == OVERLOAD && OVL_USED (ovl) && OVL_CHAIN (ovl)) 1557 ovl = OVL_CHAIN (ovl); 1558 return CP_DECL_CONTEXT (OVL_CURRENT (ovl)); 1559 } 1560 1561 /* Return TRUE if FN is a non-static member function, FALSE otherwise. 1562 This function looks into BASELINK and OVERLOAD nodes. */ 1563 1564 bool 1565 non_static_member_function_p (tree fn) 1566 { 1567 if (fn == NULL_TREE) 1568 return false; 1569 1570 if (is_overloaded_fn (fn)) 1571 fn = get_first_fn (fn); 1572 1573 return (DECL_P (fn) 1574 && DECL_NONSTATIC_MEMBER_FUNCTION_P (fn)); 1575 } 1576 1577 1578 #define PRINT_RING_SIZE 4 1579 1580 static const char * 1581 cxx_printable_name_internal (tree decl, int v, bool translate) 1582 { 1583 static unsigned int uid_ring[PRINT_RING_SIZE]; 1584 static char *print_ring[PRINT_RING_SIZE]; 1585 static bool trans_ring[PRINT_RING_SIZE]; 1586 static int ring_counter; 1587 int i; 1588 1589 /* Only cache functions. */ 1590 if (v < 2 1591 || TREE_CODE (decl) != FUNCTION_DECL 1592 || DECL_LANG_SPECIFIC (decl) == 0) 1593 return lang_decl_name (decl, v, translate); 1594 1595 /* See if this print name is lying around. */ 1596 for (i = 0; i < PRINT_RING_SIZE; i++) 1597 if (uid_ring[i] == DECL_UID (decl) && translate == trans_ring[i]) 1598 /* yes, so return it. */ 1599 return print_ring[i]; 1600 1601 if (++ring_counter == PRINT_RING_SIZE) 1602 ring_counter = 0; 1603 1604 if (current_function_decl != NULL_TREE) 1605 { 1606 /* There may be both translated and untranslated versions of the 1607 name cached. */ 1608 for (i = 0; i < 2; i++) 1609 { 1610 if (uid_ring[ring_counter] == DECL_UID (current_function_decl)) 1611 ring_counter += 1; 1612 if (ring_counter == PRINT_RING_SIZE) 1613 ring_counter = 0; 1614 } 1615 gcc_assert (uid_ring[ring_counter] != DECL_UID (current_function_decl)); 1616 } 1617 1618 free (print_ring[ring_counter]); 1619 1620 print_ring[ring_counter] = xstrdup (lang_decl_name (decl, v, translate)); 1621 uid_ring[ring_counter] = DECL_UID (decl); 1622 trans_ring[ring_counter] = translate; 1623 return print_ring[ring_counter]; 1624 } 1625 1626 const char * 1627 cxx_printable_name (tree decl, int v) 1628 { 1629 return cxx_printable_name_internal (decl, v, false); 1630 } 1631 1632 const char * 1633 cxx_printable_name_translate (tree decl, int v) 1634 { 1635 return cxx_printable_name_internal (decl, v, true); 1636 } 1637 1638 /* Build the FUNCTION_TYPE or METHOD_TYPE which may throw exceptions 1639 listed in RAISES. */ 1640 1641 tree 1642 build_exception_variant (tree type, tree raises) 1643 { 1644 tree v; 1645 int type_quals; 1646 1647 if (comp_except_specs (raises, TYPE_RAISES_EXCEPTIONS (type), ce_exact)) 1648 return type; 1649 1650 type_quals = TYPE_QUALS (type); 1651 for (v = TYPE_MAIN_VARIANT (type); v; v = TYPE_NEXT_VARIANT (v)) 1652 if (check_qualified_type (v, type, type_quals) 1653 && comp_except_specs (raises, TYPE_RAISES_EXCEPTIONS (v), ce_exact)) 1654 return v; 1655 1656 /* Need to build a new variant. */ 1657 v = build_variant_type_copy (type); 1658 TYPE_RAISES_EXCEPTIONS (v) = raises; 1659 return v; 1660 } 1661 1662 /* Given a TEMPLATE_TEMPLATE_PARM node T, create a new 1663 BOUND_TEMPLATE_TEMPLATE_PARM bound with NEWARGS as its template 1664 arguments. */ 1665 1666 tree 1667 bind_template_template_parm (tree t, tree newargs) 1668 { 1669 tree decl = TYPE_NAME (t); 1670 tree t2; 1671 1672 t2 = cxx_make_type (BOUND_TEMPLATE_TEMPLATE_PARM); 1673 decl = build_decl (input_location, 1674 TYPE_DECL, DECL_NAME (decl), NULL_TREE); 1675 1676 /* These nodes have to be created to reflect new TYPE_DECL and template 1677 arguments. */ 1678 TEMPLATE_TYPE_PARM_INDEX (t2) = copy_node (TEMPLATE_TYPE_PARM_INDEX (t)); 1679 TEMPLATE_PARM_DECL (TEMPLATE_TYPE_PARM_INDEX (t2)) = decl; 1680 TEMPLATE_TEMPLATE_PARM_TEMPLATE_INFO (t2) 1681 = build_template_info (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t), newargs); 1682 1683 TREE_TYPE (decl) = t2; 1684 TYPE_NAME (t2) = decl; 1685 TYPE_STUB_DECL (t2) = decl; 1686 TYPE_SIZE (t2) = 0; 1687 SET_TYPE_STRUCTURAL_EQUALITY (t2); 1688 1689 return t2; 1690 } 1691 1692 /* Called from count_trees via walk_tree. */ 1693 1694 static tree 1695 count_trees_r (tree *tp, int *walk_subtrees, void *data) 1696 { 1697 ++*((int *) data); 1698 1699 if (TYPE_P (*tp)) 1700 *walk_subtrees = 0; 1701 1702 return NULL_TREE; 1703 } 1704 1705 /* Debugging function for measuring the rough complexity of a tree 1706 representation. */ 1707 1708 int 1709 count_trees (tree t) 1710 { 1711 int n_trees = 0; 1712 cp_walk_tree_without_duplicates (&t, count_trees_r, &n_trees); 1713 return n_trees; 1714 } 1715 1716 /* Called from verify_stmt_tree via walk_tree. */ 1717 1718 static tree 1719 verify_stmt_tree_r (tree* tp, 1720 int* walk_subtrees ATTRIBUTE_UNUSED , 1721 void* data) 1722 { 1723 tree t = *tp; 1724 htab_t *statements = (htab_t *) data; 1725 void **slot; 1726 1727 if (!STATEMENT_CODE_P (TREE_CODE (t))) 1728 return NULL_TREE; 1729 1730 /* If this statement is already present in the hash table, then 1731 there is a circularity in the statement tree. */ 1732 gcc_assert (!htab_find (*statements, t)); 1733 1734 slot = htab_find_slot (*statements, t, INSERT); 1735 *slot = t; 1736 1737 return NULL_TREE; 1738 } 1739 1740 /* Debugging function to check that the statement T has not been 1741 corrupted. For now, this function simply checks that T contains no 1742 circularities. */ 1743 1744 void 1745 verify_stmt_tree (tree t) 1746 { 1747 htab_t statements; 1748 statements = htab_create (37, htab_hash_pointer, htab_eq_pointer, NULL); 1749 cp_walk_tree (&t, verify_stmt_tree_r, &statements, NULL); 1750 htab_delete (statements); 1751 } 1752 1753 /* Check if the type T depends on a type with no linkage and if so, return 1754 it. If RELAXED_P then do not consider a class type declared within 1755 a vague-linkage function to have no linkage. */ 1756 1757 tree 1758 no_linkage_check (tree t, bool relaxed_p) 1759 { 1760 tree r; 1761 1762 /* There's no point in checking linkage on template functions; we 1763 can't know their complete types. */ 1764 if (processing_template_decl) 1765 return NULL_TREE; 1766 1767 switch (TREE_CODE (t)) 1768 { 1769 case RECORD_TYPE: 1770 if (TYPE_PTRMEMFUNC_P (t)) 1771 goto ptrmem; 1772 /* Lambda types that don't have mangling scope have no linkage. We 1773 check CLASSTYPE_LAMBDA_EXPR here rather than LAMBDA_TYPE_P because 1774 when we get here from pushtag none of the lambda information is 1775 set up yet, so we want to assume that the lambda has linkage and 1776 fix it up later if not. */ 1777 if (CLASSTYPE_LAMBDA_EXPR (t) 1778 && LAMBDA_TYPE_EXTRA_SCOPE (t) == NULL_TREE) 1779 return t; 1780 /* Fall through. */ 1781 case UNION_TYPE: 1782 if (!CLASS_TYPE_P (t)) 1783 return NULL_TREE; 1784 /* Fall through. */ 1785 case ENUMERAL_TYPE: 1786 /* Only treat anonymous types as having no linkage if they're at 1787 namespace scope. This is core issue 966. */ 1788 if (TYPE_ANONYMOUS_P (t) && TYPE_NAMESPACE_SCOPE_P (t)) 1789 return t; 1790 1791 for (r = CP_TYPE_CONTEXT (t); ; ) 1792 { 1793 /* If we're a nested type of a !TREE_PUBLIC class, we might not 1794 have linkage, or we might just be in an anonymous namespace. 1795 If we're in a TREE_PUBLIC class, we have linkage. */ 1796 if (TYPE_P (r) && !TREE_PUBLIC (TYPE_NAME (r))) 1797 return no_linkage_check (TYPE_CONTEXT (t), relaxed_p); 1798 else if (TREE_CODE (r) == FUNCTION_DECL) 1799 { 1800 if (!relaxed_p || !vague_linkage_p (r)) 1801 return t; 1802 else 1803 r = CP_DECL_CONTEXT (r); 1804 } 1805 else 1806 break; 1807 } 1808 1809 return NULL_TREE; 1810 1811 case ARRAY_TYPE: 1812 case POINTER_TYPE: 1813 case REFERENCE_TYPE: 1814 return no_linkage_check (TREE_TYPE (t), relaxed_p); 1815 1816 case OFFSET_TYPE: 1817 ptrmem: 1818 r = no_linkage_check (TYPE_PTRMEM_POINTED_TO_TYPE (t), 1819 relaxed_p); 1820 if (r) 1821 return r; 1822 return no_linkage_check (TYPE_PTRMEM_CLASS_TYPE (t), relaxed_p); 1823 1824 case METHOD_TYPE: 1825 r = no_linkage_check (TYPE_METHOD_BASETYPE (t), relaxed_p); 1826 if (r) 1827 return r; 1828 /* Fall through. */ 1829 case FUNCTION_TYPE: 1830 { 1831 tree parm; 1832 for (parm = TYPE_ARG_TYPES (t); 1833 parm && parm != void_list_node; 1834 parm = TREE_CHAIN (parm)) 1835 { 1836 r = no_linkage_check (TREE_VALUE (parm), relaxed_p); 1837 if (r) 1838 return r; 1839 } 1840 return no_linkage_check (TREE_TYPE (t), relaxed_p); 1841 } 1842 1843 default: 1844 return NULL_TREE; 1845 } 1846 } 1847 1848 #ifdef GATHER_STATISTICS 1849 extern int depth_reached; 1850 #endif 1851 1852 void 1853 cxx_print_statistics (void) 1854 { 1855 print_search_statistics (); 1856 print_class_statistics (); 1857 print_template_statistics (); 1858 #ifdef GATHER_STATISTICS 1859 fprintf (stderr, "maximum template instantiation depth reached: %d\n", 1860 depth_reached); 1861 #endif 1862 } 1863 1864 /* Return, as an INTEGER_CST node, the number of elements for TYPE 1865 (which is an ARRAY_TYPE). This counts only elements of the top 1866 array. */ 1867 1868 tree 1869 array_type_nelts_top (tree type) 1870 { 1871 return fold_build2_loc (input_location, 1872 PLUS_EXPR, sizetype, 1873 array_type_nelts (type), 1874 size_one_node); 1875 } 1876 1877 /* Return, as an INTEGER_CST node, the number of elements for TYPE 1878 (which is an ARRAY_TYPE). This one is a recursive count of all 1879 ARRAY_TYPEs that are clumped together. */ 1880 1881 tree 1882 array_type_nelts_total (tree type) 1883 { 1884 tree sz = array_type_nelts_top (type); 1885 type = TREE_TYPE (type); 1886 while (TREE_CODE (type) == ARRAY_TYPE) 1887 { 1888 tree n = array_type_nelts_top (type); 1889 sz = fold_build2_loc (input_location, 1890 MULT_EXPR, sizetype, sz, n); 1891 type = TREE_TYPE (type); 1892 } 1893 return sz; 1894 } 1895 1896 /* Called from break_out_target_exprs via mapcar. */ 1897 1898 static tree 1899 bot_manip (tree* tp, int* walk_subtrees, void* data) 1900 { 1901 splay_tree target_remap = ((splay_tree) data); 1902 tree t = *tp; 1903 1904 if (!TYPE_P (t) && TREE_CONSTANT (t) && !TREE_SIDE_EFFECTS (t)) 1905 { 1906 /* There can't be any TARGET_EXPRs or their slot variables below this 1907 point. But we must make a copy, in case subsequent processing 1908 alters any part of it. For example, during gimplification a cast 1909 of the form (T) &X::f (where "f" is a member function) will lead 1910 to replacing the PTRMEM_CST for &X::f with a VAR_DECL. */ 1911 *walk_subtrees = 0; 1912 *tp = unshare_expr (t); 1913 return NULL_TREE; 1914 } 1915 if (TREE_CODE (t) == TARGET_EXPR) 1916 { 1917 tree u; 1918 1919 if (TREE_CODE (TREE_OPERAND (t, 1)) == AGGR_INIT_EXPR) 1920 { 1921 u = build_cplus_new (TREE_TYPE (t), TREE_OPERAND (t, 1), 1922 tf_warning_or_error); 1923 if (AGGR_INIT_ZERO_FIRST (TREE_OPERAND (t, 1))) 1924 AGGR_INIT_ZERO_FIRST (TREE_OPERAND (u, 1)) = true; 1925 } 1926 else 1927 u = build_target_expr_with_type (TREE_OPERAND (t, 1), TREE_TYPE (t), 1928 tf_warning_or_error); 1929 1930 TARGET_EXPR_IMPLICIT_P (u) = TARGET_EXPR_IMPLICIT_P (t); 1931 TARGET_EXPR_LIST_INIT_P (u) = TARGET_EXPR_LIST_INIT_P (t); 1932 TARGET_EXPR_DIRECT_INIT_P (u) = TARGET_EXPR_DIRECT_INIT_P (t); 1933 1934 /* Map the old variable to the new one. */ 1935 splay_tree_insert (target_remap, 1936 (splay_tree_key) TREE_OPERAND (t, 0), 1937 (splay_tree_value) TREE_OPERAND (u, 0)); 1938 1939 TREE_OPERAND (u, 1) = break_out_target_exprs (TREE_OPERAND (u, 1)); 1940 1941 /* Replace the old expression with the new version. */ 1942 *tp = u; 1943 /* We don't have to go below this point; the recursive call to 1944 break_out_target_exprs will have handled anything below this 1945 point. */ 1946 *walk_subtrees = 0; 1947 return NULL_TREE; 1948 } 1949 1950 /* Make a copy of this node. */ 1951 t = copy_tree_r (tp, walk_subtrees, NULL); 1952 if (TREE_CODE (*tp) == CALL_EXPR) 1953 set_flags_from_callee (*tp); 1954 return t; 1955 } 1956 1957 /* Replace all remapped VAR_DECLs in T with their new equivalents. 1958 DATA is really a splay-tree mapping old variables to new 1959 variables. */ 1960 1961 static tree 1962 bot_replace (tree* t, 1963 int* walk_subtrees ATTRIBUTE_UNUSED , 1964 void* data) 1965 { 1966 splay_tree target_remap = ((splay_tree) data); 1967 1968 if (TREE_CODE (*t) == VAR_DECL) 1969 { 1970 splay_tree_node n = splay_tree_lookup (target_remap, 1971 (splay_tree_key) *t); 1972 if (n) 1973 *t = (tree) n->value; 1974 } 1975 else if (TREE_CODE (*t) == PARM_DECL 1976 && DECL_NAME (*t) == this_identifier) 1977 { 1978 /* In an NSDMI we need to replace the 'this' parameter we used for 1979 parsing with the real one for this function. */ 1980 *t = current_class_ptr; 1981 } 1982 else if (TREE_CODE (*t) == CONVERT_EXPR 1983 && CONVERT_EXPR_VBASE_PATH (*t)) 1984 { 1985 /* In an NSDMI build_base_path defers building conversions to virtual 1986 bases, and we handle it here. */ 1987 tree basetype = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (*t))); 1988 VEC(tree,gc) *vbases = CLASSTYPE_VBASECLASSES (current_class_type); 1989 int i; tree binfo; 1990 FOR_EACH_VEC_ELT (tree, vbases, i, binfo) 1991 if (BINFO_TYPE (binfo) == basetype) 1992 break; 1993 *t = build_base_path (PLUS_EXPR, TREE_OPERAND (*t, 0), binfo, true, 1994 tf_warning_or_error); 1995 } 1996 1997 return NULL_TREE; 1998 } 1999 2000 /* When we parse a default argument expression, we may create 2001 temporary variables via TARGET_EXPRs. When we actually use the 2002 default-argument expression, we make a copy of the expression 2003 and replace the temporaries with appropriate local versions. */ 2004 2005 tree 2006 break_out_target_exprs (tree t) 2007 { 2008 static int target_remap_count; 2009 static splay_tree target_remap; 2010 2011 if (!target_remap_count++) 2012 target_remap = splay_tree_new (splay_tree_compare_pointers, 2013 /*splay_tree_delete_key_fn=*/NULL, 2014 /*splay_tree_delete_value_fn=*/NULL); 2015 cp_walk_tree (&t, bot_manip, target_remap, NULL); 2016 cp_walk_tree (&t, bot_replace, target_remap, NULL); 2017 2018 if (!--target_remap_count) 2019 { 2020 splay_tree_delete (target_remap); 2021 target_remap = NULL; 2022 } 2023 2024 return t; 2025 } 2026 2027 /* Similar to `build_nt', but for template definitions of dependent 2028 expressions */ 2029 2030 tree 2031 build_min_nt (enum tree_code code, ...) 2032 { 2033 tree t; 2034 int length; 2035 int i; 2036 va_list p; 2037 2038 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp); 2039 2040 va_start (p, code); 2041 2042 t = make_node (code); 2043 length = TREE_CODE_LENGTH (code); 2044 2045 for (i = 0; i < length; i++) 2046 { 2047 tree x = va_arg (p, tree); 2048 TREE_OPERAND (t, i) = x; 2049 } 2050 2051 va_end (p); 2052 return t; 2053 } 2054 2055 2056 /* Similar to `build', but for template definitions. */ 2057 2058 tree 2059 build_min (enum tree_code code, tree tt, ...) 2060 { 2061 tree t; 2062 int length; 2063 int i; 2064 va_list p; 2065 2066 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp); 2067 2068 va_start (p, tt); 2069 2070 t = make_node (code); 2071 length = TREE_CODE_LENGTH (code); 2072 TREE_TYPE (t) = tt; 2073 2074 for (i = 0; i < length; i++) 2075 { 2076 tree x = va_arg (p, tree); 2077 TREE_OPERAND (t, i) = x; 2078 if (x && !TYPE_P (x) && TREE_SIDE_EFFECTS (x)) 2079 TREE_SIDE_EFFECTS (t) = 1; 2080 } 2081 2082 va_end (p); 2083 return t; 2084 } 2085 2086 /* Similar to `build', but for template definitions of non-dependent 2087 expressions. NON_DEP is the non-dependent expression that has been 2088 built. */ 2089 2090 tree 2091 build_min_non_dep (enum tree_code code, tree non_dep, ...) 2092 { 2093 tree t; 2094 int length; 2095 int i; 2096 va_list p; 2097 2098 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp); 2099 2100 va_start (p, non_dep); 2101 2102 if (REFERENCE_REF_P (non_dep)) 2103 non_dep = TREE_OPERAND (non_dep, 0); 2104 2105 t = make_node (code); 2106 length = TREE_CODE_LENGTH (code); 2107 TREE_TYPE (t) = TREE_TYPE (non_dep); 2108 TREE_SIDE_EFFECTS (t) = TREE_SIDE_EFFECTS (non_dep); 2109 2110 for (i = 0; i < length; i++) 2111 { 2112 tree x = va_arg (p, tree); 2113 TREE_OPERAND (t, i) = x; 2114 } 2115 2116 if (code == COMPOUND_EXPR && TREE_CODE (non_dep) != COMPOUND_EXPR) 2117 /* This should not be considered a COMPOUND_EXPR, because it 2118 resolves to an overload. */ 2119 COMPOUND_EXPR_OVERLOADED (t) = 1; 2120 2121 va_end (p); 2122 return convert_from_reference (t); 2123 } 2124 2125 /* Similar to `build_nt_call_vec', but for template definitions of 2126 non-dependent expressions. NON_DEP is the non-dependent expression 2127 that has been built. */ 2128 2129 tree 2130 build_min_non_dep_call_vec (tree non_dep, tree fn, VEC(tree,gc) *argvec) 2131 { 2132 tree t = build_nt_call_vec (fn, argvec); 2133 if (REFERENCE_REF_P (non_dep)) 2134 non_dep = TREE_OPERAND (non_dep, 0); 2135 TREE_TYPE (t) = TREE_TYPE (non_dep); 2136 TREE_SIDE_EFFECTS (t) = TREE_SIDE_EFFECTS (non_dep); 2137 return convert_from_reference (t); 2138 } 2139 2140 tree 2141 get_type_decl (tree t) 2142 { 2143 if (TREE_CODE (t) == TYPE_DECL) 2144 return t; 2145 if (TYPE_P (t)) 2146 return TYPE_STUB_DECL (t); 2147 gcc_assert (t == error_mark_node); 2148 return t; 2149 } 2150 2151 /* Returns the namespace that contains DECL, whether directly or 2152 indirectly. */ 2153 2154 tree 2155 decl_namespace_context (tree decl) 2156 { 2157 while (1) 2158 { 2159 if (TREE_CODE (decl) == NAMESPACE_DECL) 2160 return decl; 2161 else if (TYPE_P (decl)) 2162 decl = CP_DECL_CONTEXT (TYPE_MAIN_DECL (decl)); 2163 else 2164 decl = CP_DECL_CONTEXT (decl); 2165 } 2166 } 2167 2168 /* Returns true if decl is within an anonymous namespace, however deeply 2169 nested, or false otherwise. */ 2170 2171 bool 2172 decl_anon_ns_mem_p (const_tree decl) 2173 { 2174 while (1) 2175 { 2176 if (decl == NULL_TREE || decl == error_mark_node) 2177 return false; 2178 if (TREE_CODE (decl) == NAMESPACE_DECL 2179 && DECL_NAME (decl) == NULL_TREE) 2180 return true; 2181 /* Classes and namespaces inside anonymous namespaces have 2182 TREE_PUBLIC == 0, so we can shortcut the search. */ 2183 else if (TYPE_P (decl)) 2184 return (TREE_PUBLIC (TYPE_NAME (decl)) == 0); 2185 else if (TREE_CODE (decl) == NAMESPACE_DECL) 2186 return (TREE_PUBLIC (decl) == 0); 2187 else 2188 decl = DECL_CONTEXT (decl); 2189 } 2190 } 2191 2192 /* Subroutine of cp_tree_equal: t1 and t2 are the CALL_EXPR_FNs of two 2193 CALL_EXPRS. Return whether they are equivalent. */ 2194 2195 static bool 2196 called_fns_equal (tree t1, tree t2) 2197 { 2198 /* Core 1321: dependent names are equivalent even if the overload sets 2199 are different. But do compare explicit template arguments. */ 2200 tree name1 = dependent_name (t1); 2201 tree name2 = dependent_name (t2); 2202 if (name1 || name2) 2203 { 2204 tree targs1 = NULL_TREE, targs2 = NULL_TREE; 2205 2206 if (name1 != name2) 2207 return false; 2208 2209 if (TREE_CODE (t1) == TEMPLATE_ID_EXPR) 2210 targs1 = TREE_OPERAND (t1, 1); 2211 if (TREE_CODE (t2) == TEMPLATE_ID_EXPR) 2212 targs2 = TREE_OPERAND (t2, 1); 2213 return cp_tree_equal (targs1, targs2); 2214 } 2215 else 2216 return cp_tree_equal (t1, t2); 2217 } 2218 2219 /* Return truthvalue of whether T1 is the same tree structure as T2. 2220 Return 1 if they are the same. Return 0 if they are different. */ 2221 2222 bool 2223 cp_tree_equal (tree t1, tree t2) 2224 { 2225 enum tree_code code1, code2; 2226 2227 if (t1 == t2) 2228 return true; 2229 if (!t1 || !t2) 2230 return false; 2231 2232 for (code1 = TREE_CODE (t1); 2233 CONVERT_EXPR_CODE_P (code1) 2234 || code1 == NON_LVALUE_EXPR; 2235 code1 = TREE_CODE (t1)) 2236 t1 = TREE_OPERAND (t1, 0); 2237 for (code2 = TREE_CODE (t2); 2238 CONVERT_EXPR_CODE_P (code2) 2239 || code1 == NON_LVALUE_EXPR; 2240 code2 = TREE_CODE (t2)) 2241 t2 = TREE_OPERAND (t2, 0); 2242 2243 /* They might have become equal now. */ 2244 if (t1 == t2) 2245 return true; 2246 2247 if (code1 != code2) 2248 return false; 2249 2250 switch (code1) 2251 { 2252 case INTEGER_CST: 2253 return TREE_INT_CST_LOW (t1) == TREE_INT_CST_LOW (t2) 2254 && TREE_INT_CST_HIGH (t1) == TREE_INT_CST_HIGH (t2); 2255 2256 case REAL_CST: 2257 return REAL_VALUES_EQUAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2)); 2258 2259 case STRING_CST: 2260 return TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2) 2261 && !memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2), 2262 TREE_STRING_LENGTH (t1)); 2263 2264 case FIXED_CST: 2265 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), 2266 TREE_FIXED_CST (t2)); 2267 2268 case COMPLEX_CST: 2269 return cp_tree_equal (TREE_REALPART (t1), TREE_REALPART (t2)) 2270 && cp_tree_equal (TREE_IMAGPART (t1), TREE_IMAGPART (t2)); 2271 2272 case CONSTRUCTOR: 2273 /* We need to do this when determining whether or not two 2274 non-type pointer to member function template arguments 2275 are the same. */ 2276 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)) 2277 || CONSTRUCTOR_NELTS (t1) != CONSTRUCTOR_NELTS (t2)) 2278 return false; 2279 { 2280 tree field, value; 2281 unsigned int i; 2282 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (t1), i, field, value) 2283 { 2284 constructor_elt *elt2 = CONSTRUCTOR_ELT (t2, i); 2285 if (!cp_tree_equal (field, elt2->index) 2286 || !cp_tree_equal (value, elt2->value)) 2287 return false; 2288 } 2289 } 2290 return true; 2291 2292 case TREE_LIST: 2293 if (!cp_tree_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2))) 2294 return false; 2295 if (!cp_tree_equal (TREE_VALUE (t1), TREE_VALUE (t2))) 2296 return false; 2297 return cp_tree_equal (TREE_CHAIN (t1), TREE_CHAIN (t2)); 2298 2299 case SAVE_EXPR: 2300 return cp_tree_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0)); 2301 2302 case CALL_EXPR: 2303 { 2304 tree arg1, arg2; 2305 call_expr_arg_iterator iter1, iter2; 2306 if (!called_fns_equal (CALL_EXPR_FN (t1), CALL_EXPR_FN (t2))) 2307 return false; 2308 for (arg1 = first_call_expr_arg (t1, &iter1), 2309 arg2 = first_call_expr_arg (t2, &iter2); 2310 arg1 && arg2; 2311 arg1 = next_call_expr_arg (&iter1), 2312 arg2 = next_call_expr_arg (&iter2)) 2313 if (!cp_tree_equal (arg1, arg2)) 2314 return false; 2315 if (arg1 || arg2) 2316 return false; 2317 return true; 2318 } 2319 2320 case TARGET_EXPR: 2321 { 2322 tree o1 = TREE_OPERAND (t1, 0); 2323 tree o2 = TREE_OPERAND (t2, 0); 2324 2325 /* Special case: if either target is an unallocated VAR_DECL, 2326 it means that it's going to be unified with whatever the 2327 TARGET_EXPR is really supposed to initialize, so treat it 2328 as being equivalent to anything. */ 2329 if (TREE_CODE (o1) == VAR_DECL && DECL_NAME (o1) == NULL_TREE 2330 && !DECL_RTL_SET_P (o1)) 2331 /*Nop*/; 2332 else if (TREE_CODE (o2) == VAR_DECL && DECL_NAME (o2) == NULL_TREE 2333 && !DECL_RTL_SET_P (o2)) 2334 /*Nop*/; 2335 else if (!cp_tree_equal (o1, o2)) 2336 return false; 2337 2338 return cp_tree_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)); 2339 } 2340 2341 case WITH_CLEANUP_EXPR: 2342 if (!cp_tree_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))) 2343 return false; 2344 return cp_tree_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t1, 1)); 2345 2346 case COMPONENT_REF: 2347 if (TREE_OPERAND (t1, 1) != TREE_OPERAND (t2, 1)) 2348 return false; 2349 return cp_tree_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0)); 2350 2351 case PARM_DECL: 2352 /* For comparing uses of parameters in late-specified return types 2353 with an out-of-class definition of the function, but can also come 2354 up for expressions that involve 'this' in a member function 2355 template. */ 2356 if (same_type_p (TREE_TYPE (t1), TREE_TYPE (t2))) 2357 { 2358 if (DECL_ARTIFICIAL (t1) ^ DECL_ARTIFICIAL (t2)) 2359 return false; 2360 if (DECL_ARTIFICIAL (t1) 2361 || (DECL_PARM_LEVEL (t1) == DECL_PARM_LEVEL (t2) 2362 && DECL_PARM_INDEX (t1) == DECL_PARM_INDEX (t2))) 2363 return true; 2364 } 2365 return false; 2366 2367 case VAR_DECL: 2368 case CONST_DECL: 2369 case FUNCTION_DECL: 2370 case TEMPLATE_DECL: 2371 case IDENTIFIER_NODE: 2372 case SSA_NAME: 2373 return false; 2374 2375 case BASELINK: 2376 return (BASELINK_BINFO (t1) == BASELINK_BINFO (t2) 2377 && BASELINK_ACCESS_BINFO (t1) == BASELINK_ACCESS_BINFO (t2) 2378 && BASELINK_QUALIFIED_P (t1) == BASELINK_QUALIFIED_P (t2) 2379 && cp_tree_equal (BASELINK_FUNCTIONS (t1), 2380 BASELINK_FUNCTIONS (t2))); 2381 2382 case TEMPLATE_PARM_INDEX: 2383 if (TEMPLATE_PARM_NUM_SIBLINGS (t1) 2384 != TEMPLATE_PARM_NUM_SIBLINGS (t2)) 2385 return false; 2386 return (TEMPLATE_PARM_IDX (t1) == TEMPLATE_PARM_IDX (t2) 2387 && TEMPLATE_PARM_LEVEL (t1) == TEMPLATE_PARM_LEVEL (t2) 2388 && (TEMPLATE_PARM_PARAMETER_PACK (t1) 2389 == TEMPLATE_PARM_PARAMETER_PACK (t2)) 2390 && same_type_p (TREE_TYPE (TEMPLATE_PARM_DECL (t1)), 2391 TREE_TYPE (TEMPLATE_PARM_DECL (t2)))); 2392 2393 case TEMPLATE_ID_EXPR: 2394 return (cp_tree_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0)) 2395 && cp_tree_equal (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1))); 2396 2397 case TREE_VEC: 2398 { 2399 unsigned ix; 2400 if (TREE_VEC_LENGTH (t1) != TREE_VEC_LENGTH (t2)) 2401 return false; 2402 for (ix = TREE_VEC_LENGTH (t1); ix--;) 2403 if (!cp_tree_equal (TREE_VEC_ELT (t1, ix), 2404 TREE_VEC_ELT (t2, ix))) 2405 return false; 2406 return true; 2407 } 2408 2409 case SIZEOF_EXPR: 2410 case ALIGNOF_EXPR: 2411 { 2412 tree o1 = TREE_OPERAND (t1, 0); 2413 tree o2 = TREE_OPERAND (t2, 0); 2414 2415 if (TREE_CODE (o1) != TREE_CODE (o2)) 2416 return false; 2417 if (TYPE_P (o1)) 2418 return same_type_p (o1, o2); 2419 else 2420 return cp_tree_equal (o1, o2); 2421 } 2422 2423 case MODOP_EXPR: 2424 { 2425 tree t1_op1, t2_op1; 2426 2427 if (!cp_tree_equal (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))) 2428 return false; 2429 2430 t1_op1 = TREE_OPERAND (t1, 1); 2431 t2_op1 = TREE_OPERAND (t2, 1); 2432 if (TREE_CODE (t1_op1) != TREE_CODE (t2_op1)) 2433 return false; 2434 2435 return cp_tree_equal (TREE_OPERAND (t1, 2), TREE_OPERAND (t2, 2)); 2436 } 2437 2438 case PTRMEM_CST: 2439 /* Two pointer-to-members are the same if they point to the same 2440 field or function in the same class. */ 2441 if (PTRMEM_CST_MEMBER (t1) != PTRMEM_CST_MEMBER (t2)) 2442 return false; 2443 2444 return same_type_p (PTRMEM_CST_CLASS (t1), PTRMEM_CST_CLASS (t2)); 2445 2446 case OVERLOAD: 2447 if (OVL_FUNCTION (t1) != OVL_FUNCTION (t2)) 2448 return false; 2449 return cp_tree_equal (OVL_CHAIN (t1), OVL_CHAIN (t2)); 2450 2451 case TRAIT_EXPR: 2452 if (TRAIT_EXPR_KIND (t1) != TRAIT_EXPR_KIND (t2)) 2453 return false; 2454 return same_type_p (TRAIT_EXPR_TYPE1 (t1), TRAIT_EXPR_TYPE1 (t2)) 2455 && same_type_p (TRAIT_EXPR_TYPE2 (t1), TRAIT_EXPR_TYPE2 (t2)); 2456 2457 case CAST_EXPR: 2458 case STATIC_CAST_EXPR: 2459 case REINTERPRET_CAST_EXPR: 2460 case CONST_CAST_EXPR: 2461 case DYNAMIC_CAST_EXPR: 2462 case IMPLICIT_CONV_EXPR: 2463 case NEW_EXPR: 2464 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2))) 2465 return false; 2466 /* Now compare operands as usual. */ 2467 break; 2468 2469 case DEFERRED_NOEXCEPT: 2470 return (cp_tree_equal (DEFERRED_NOEXCEPT_PATTERN (t1), 2471 DEFERRED_NOEXCEPT_PATTERN (t2)) 2472 && comp_template_args (DEFERRED_NOEXCEPT_ARGS (t1), 2473 DEFERRED_NOEXCEPT_ARGS (t2))); 2474 break; 2475 2476 default: 2477 break; 2478 } 2479 2480 switch (TREE_CODE_CLASS (code1)) 2481 { 2482 case tcc_unary: 2483 case tcc_binary: 2484 case tcc_comparison: 2485 case tcc_expression: 2486 case tcc_vl_exp: 2487 case tcc_reference: 2488 case tcc_statement: 2489 { 2490 int i, n; 2491 2492 n = cp_tree_operand_length (t1); 2493 if (TREE_CODE_CLASS (code1) == tcc_vl_exp 2494 && n != TREE_OPERAND_LENGTH (t2)) 2495 return false; 2496 2497 for (i = 0; i < n; ++i) 2498 if (!cp_tree_equal (TREE_OPERAND (t1, i), TREE_OPERAND (t2, i))) 2499 return false; 2500 2501 return true; 2502 } 2503 2504 case tcc_type: 2505 return same_type_p (t1, t2); 2506 default: 2507 gcc_unreachable (); 2508 } 2509 /* We can get here with --disable-checking. */ 2510 return false; 2511 } 2512 2513 /* The type of ARG when used as an lvalue. */ 2514 2515 tree 2516 lvalue_type (tree arg) 2517 { 2518 tree type = TREE_TYPE (arg); 2519 return type; 2520 } 2521 2522 /* The type of ARG for printing error messages; denote lvalues with 2523 reference types. */ 2524 2525 tree 2526 error_type (tree arg) 2527 { 2528 tree type = TREE_TYPE (arg); 2529 2530 if (TREE_CODE (type) == ARRAY_TYPE) 2531 ; 2532 else if (TREE_CODE (type) == ERROR_MARK) 2533 ; 2534 else if (real_lvalue_p (arg)) 2535 type = build_reference_type (lvalue_type (arg)); 2536 else if (MAYBE_CLASS_TYPE_P (type)) 2537 type = lvalue_type (arg); 2538 2539 return type; 2540 } 2541 2542 /* Does FUNCTION use a variable-length argument list? */ 2543 2544 int 2545 varargs_function_p (const_tree function) 2546 { 2547 return stdarg_p (TREE_TYPE (function)); 2548 } 2549 2550 /* Returns 1 if decl is a member of a class. */ 2551 2552 int 2553 member_p (const_tree decl) 2554 { 2555 const_tree const ctx = DECL_CONTEXT (decl); 2556 return (ctx && TYPE_P (ctx)); 2557 } 2558 2559 /* Create a placeholder for member access where we don't actually have an 2560 object that the access is against. */ 2561 2562 tree 2563 build_dummy_object (tree type) 2564 { 2565 tree decl = build1 (NOP_EXPR, build_pointer_type (type), void_zero_node); 2566 return cp_build_indirect_ref (decl, RO_NULL, tf_warning_or_error); 2567 } 2568 2569 /* We've gotten a reference to a member of TYPE. Return *this if appropriate, 2570 or a dummy object otherwise. If BINFOP is non-0, it is filled with the 2571 binfo path from current_class_type to TYPE, or 0. */ 2572 2573 tree 2574 maybe_dummy_object (tree type, tree* binfop) 2575 { 2576 tree decl, context; 2577 tree binfo; 2578 tree current = current_nonlambda_class_type (); 2579 2580 if (current 2581 && (binfo = lookup_base (current, type, ba_any, NULL))) 2582 context = current; 2583 else 2584 { 2585 /* Reference from a nested class member function. */ 2586 context = type; 2587 binfo = TYPE_BINFO (type); 2588 } 2589 2590 if (binfop) 2591 *binfop = binfo; 2592 2593 if (current_class_ref 2594 /* current_class_ref might not correspond to current_class_type if 2595 we're in tsubst_default_argument or a lambda-declarator; in either 2596 case, we want to use current_class_ref if it matches CONTEXT. */ 2597 && (same_type_ignoring_top_level_qualifiers_p 2598 (TREE_TYPE (current_class_ref), context))) 2599 decl = current_class_ref; 2600 else if (current != current_class_type 2601 && context == nonlambda_method_basetype ()) 2602 /* In a lambda, need to go through 'this' capture. */ 2603 decl = (build_x_indirect_ref 2604 ((lambda_expr_this_capture 2605 (CLASSTYPE_LAMBDA_EXPR (current_class_type))), 2606 RO_NULL, tf_warning_or_error)); 2607 else 2608 decl = build_dummy_object (context); 2609 2610 return decl; 2611 } 2612 2613 /* Returns 1 if OB is a placeholder object, or a pointer to one. */ 2614 2615 int 2616 is_dummy_object (const_tree ob) 2617 { 2618 if (TREE_CODE (ob) == INDIRECT_REF) 2619 ob = TREE_OPERAND (ob, 0); 2620 return (TREE_CODE (ob) == NOP_EXPR 2621 && TREE_OPERAND (ob, 0) == void_zero_node); 2622 } 2623 2624 /* Returns 1 iff type T is something we want to treat as a scalar type for 2625 the purpose of deciding whether it is trivial/POD/standard-layout. */ 2626 2627 static bool 2628 scalarish_type_p (const_tree t) 2629 { 2630 if (t == error_mark_node) 2631 return 1; 2632 2633 return (SCALAR_TYPE_P (t) 2634 || TREE_CODE (t) == VECTOR_TYPE); 2635 } 2636 2637 /* Returns true iff T requires non-trivial default initialization. */ 2638 2639 bool 2640 type_has_nontrivial_default_init (const_tree t) 2641 { 2642 t = strip_array_types (CONST_CAST_TREE (t)); 2643 2644 if (CLASS_TYPE_P (t)) 2645 return TYPE_HAS_COMPLEX_DFLT (t); 2646 else 2647 return 0; 2648 } 2649 2650 /* Returns true iff copying an object of type T (including via move 2651 constructor) is non-trivial. That is, T has no non-trivial copy 2652 constructors and no non-trivial move constructors. */ 2653 2654 bool 2655 type_has_nontrivial_copy_init (const_tree t) 2656 { 2657 t = strip_array_types (CONST_CAST_TREE (t)); 2658 2659 if (CLASS_TYPE_P (t)) 2660 { 2661 gcc_assert (COMPLETE_TYPE_P (t)); 2662 return ((TYPE_HAS_COPY_CTOR (t) 2663 && TYPE_HAS_COMPLEX_COPY_CTOR (t)) 2664 || TYPE_HAS_COMPLEX_MOVE_CTOR (t)); 2665 } 2666 else 2667 return 0; 2668 } 2669 2670 /* Returns 1 iff type T is a trivially copyable type, as defined in 2671 [basic.types] and [class]. */ 2672 2673 bool 2674 trivially_copyable_p (const_tree t) 2675 { 2676 t = strip_array_types (CONST_CAST_TREE (t)); 2677 2678 if (CLASS_TYPE_P (t)) 2679 return ((!TYPE_HAS_COPY_CTOR (t) 2680 || !TYPE_HAS_COMPLEX_COPY_CTOR (t)) 2681 && !TYPE_HAS_COMPLEX_MOVE_CTOR (t) 2682 && (!TYPE_HAS_COPY_ASSIGN (t) 2683 || !TYPE_HAS_COMPLEX_COPY_ASSIGN (t)) 2684 && !TYPE_HAS_COMPLEX_MOVE_ASSIGN (t) 2685 && TYPE_HAS_TRIVIAL_DESTRUCTOR (t)); 2686 else 2687 return scalarish_type_p (t); 2688 } 2689 2690 /* Returns 1 iff type T is a trivial type, as defined in [basic.types] and 2691 [class]. */ 2692 2693 bool 2694 trivial_type_p (const_tree t) 2695 { 2696 t = strip_array_types (CONST_CAST_TREE (t)); 2697 2698 if (CLASS_TYPE_P (t)) 2699 return (TYPE_HAS_TRIVIAL_DFLT (t) 2700 && trivially_copyable_p (t)); 2701 else 2702 return scalarish_type_p (t); 2703 } 2704 2705 /* Returns 1 iff type T is a POD type, as defined in [basic.types]. */ 2706 2707 bool 2708 pod_type_p (const_tree t) 2709 { 2710 /* This CONST_CAST is okay because strip_array_types returns its 2711 argument unmodified and we assign it to a const_tree. */ 2712 t = strip_array_types (CONST_CAST_TREE(t)); 2713 2714 if (!CLASS_TYPE_P (t)) 2715 return scalarish_type_p (t); 2716 else if (cxx_dialect > cxx98) 2717 /* [class]/10: A POD struct is a class that is both a trivial class and a 2718 standard-layout class, and has no non-static data members of type 2719 non-POD struct, non-POD union (or array of such types). 2720 2721 We don't need to check individual members because if a member is 2722 non-std-layout or non-trivial, the class will be too. */ 2723 return (std_layout_type_p (t) && trivial_type_p (t)); 2724 else 2725 /* The C++98 definition of POD is different. */ 2726 return !CLASSTYPE_NON_LAYOUT_POD_P (t); 2727 } 2728 2729 /* Returns true iff T is POD for the purpose of layout, as defined in the 2730 C++ ABI. */ 2731 2732 bool 2733 layout_pod_type_p (const_tree t) 2734 { 2735 t = strip_array_types (CONST_CAST_TREE (t)); 2736 2737 if (CLASS_TYPE_P (t)) 2738 return !CLASSTYPE_NON_LAYOUT_POD_P (t); 2739 else 2740 return scalarish_type_p (t); 2741 } 2742 2743 /* Returns true iff T is a standard-layout type, as defined in 2744 [basic.types]. */ 2745 2746 bool 2747 std_layout_type_p (const_tree t) 2748 { 2749 t = strip_array_types (CONST_CAST_TREE (t)); 2750 2751 if (CLASS_TYPE_P (t)) 2752 return !CLASSTYPE_NON_STD_LAYOUT (t); 2753 else 2754 return scalarish_type_p (t); 2755 } 2756 2757 /* Nonzero iff type T is a class template implicit specialization. */ 2758 2759 bool 2760 class_tmpl_impl_spec_p (const_tree t) 2761 { 2762 return CLASS_TYPE_P (t) && CLASSTYPE_TEMPLATE_INSTANTIATION (t); 2763 } 2764 2765 /* Returns 1 iff zero initialization of type T means actually storing 2766 zeros in it. */ 2767 2768 int 2769 zero_init_p (const_tree t) 2770 { 2771 /* This CONST_CAST is okay because strip_array_types returns its 2772 argument unmodified and we assign it to a const_tree. */ 2773 t = strip_array_types (CONST_CAST_TREE(t)); 2774 2775 if (t == error_mark_node) 2776 return 1; 2777 2778 /* NULL pointers to data members are initialized with -1. */ 2779 if (TYPE_PTRMEM_P (t)) 2780 return 0; 2781 2782 /* Classes that contain types that can't be zero-initialized, cannot 2783 be zero-initialized themselves. */ 2784 if (CLASS_TYPE_P (t) && CLASSTYPE_NON_ZERO_INIT_P (t)) 2785 return 0; 2786 2787 return 1; 2788 } 2789 2790 /* Table of valid C++ attributes. */ 2791 const struct attribute_spec cxx_attribute_table[] = 2792 { 2793 /* { name, min_len, max_len, decl_req, type_req, fn_type_req, handler, 2794 affects_type_identity } */ 2795 { "java_interface", 0, 0, false, false, false, 2796 handle_java_interface_attribute, false }, 2797 { "com_interface", 0, 0, false, false, false, 2798 handle_com_interface_attribute, false }, 2799 { "init_priority", 1, 1, true, false, false, 2800 handle_init_priority_attribute, false }, 2801 { NULL, 0, 0, false, false, false, NULL, false } 2802 }; 2803 2804 /* Handle a "java_interface" attribute; arguments as in 2805 struct attribute_spec.handler. */ 2806 static tree 2807 handle_java_interface_attribute (tree* node, 2808 tree name, 2809 tree args ATTRIBUTE_UNUSED , 2810 int flags, 2811 bool* no_add_attrs) 2812 { 2813 if (DECL_P (*node) 2814 || !CLASS_TYPE_P (*node) 2815 || !TYPE_FOR_JAVA (*node)) 2816 { 2817 error ("%qE attribute can only be applied to Java class definitions", 2818 name); 2819 *no_add_attrs = true; 2820 return NULL_TREE; 2821 } 2822 if (!(flags & (int) ATTR_FLAG_TYPE_IN_PLACE)) 2823 *node = build_variant_type_copy (*node); 2824 TYPE_JAVA_INTERFACE (*node) = 1; 2825 2826 return NULL_TREE; 2827 } 2828 2829 /* Handle a "com_interface" attribute; arguments as in 2830 struct attribute_spec.handler. */ 2831 static tree 2832 handle_com_interface_attribute (tree* node, 2833 tree name, 2834 tree args ATTRIBUTE_UNUSED , 2835 int flags ATTRIBUTE_UNUSED , 2836 bool* no_add_attrs) 2837 { 2838 static int warned; 2839 2840 *no_add_attrs = true; 2841 2842 if (DECL_P (*node) 2843 || !CLASS_TYPE_P (*node) 2844 || *node != TYPE_MAIN_VARIANT (*node)) 2845 { 2846 warning (OPT_Wattributes, "%qE attribute can only be applied " 2847 "to class definitions", name); 2848 return NULL_TREE; 2849 } 2850 2851 if (!warned++) 2852 warning (0, "%qE is obsolete; g++ vtables are now COM-compatible by default", 2853 name); 2854 2855 return NULL_TREE; 2856 } 2857 2858 /* Handle an "init_priority" attribute; arguments as in 2859 struct attribute_spec.handler. */ 2860 static tree 2861 handle_init_priority_attribute (tree* node, 2862 tree name, 2863 tree args, 2864 int flags ATTRIBUTE_UNUSED , 2865 bool* no_add_attrs) 2866 { 2867 tree initp_expr = TREE_VALUE (args); 2868 tree decl = *node; 2869 tree type = TREE_TYPE (decl); 2870 int pri; 2871 2872 STRIP_NOPS (initp_expr); 2873 2874 if (!initp_expr || TREE_CODE (initp_expr) != INTEGER_CST) 2875 { 2876 error ("requested init_priority is not an integer constant"); 2877 *no_add_attrs = true; 2878 return NULL_TREE; 2879 } 2880 2881 pri = TREE_INT_CST_LOW (initp_expr); 2882 2883 type = strip_array_types (type); 2884 2885 if (decl == NULL_TREE 2886 || TREE_CODE (decl) != VAR_DECL 2887 || !TREE_STATIC (decl) 2888 || DECL_EXTERNAL (decl) 2889 || (TREE_CODE (type) != RECORD_TYPE 2890 && TREE_CODE (type) != UNION_TYPE) 2891 /* Static objects in functions are initialized the 2892 first time control passes through that 2893 function. This is not precise enough to pin down an 2894 init_priority value, so don't allow it. */ 2895 || current_function_decl) 2896 { 2897 error ("can only use %qE attribute on file-scope definitions " 2898 "of objects of class type", name); 2899 *no_add_attrs = true; 2900 return NULL_TREE; 2901 } 2902 2903 if (pri > MAX_INIT_PRIORITY || pri <= 0) 2904 { 2905 error ("requested init_priority is out of range"); 2906 *no_add_attrs = true; 2907 return NULL_TREE; 2908 } 2909 2910 /* Check for init_priorities that are reserved for 2911 language and runtime support implementations.*/ 2912 if (pri <= MAX_RESERVED_INIT_PRIORITY) 2913 { 2914 warning 2915 (0, "requested init_priority is reserved for internal use"); 2916 } 2917 2918 if (SUPPORTS_INIT_PRIORITY) 2919 { 2920 SET_DECL_INIT_PRIORITY (decl, pri); 2921 DECL_HAS_INIT_PRIORITY_P (decl) = 1; 2922 return NULL_TREE; 2923 } 2924 else 2925 { 2926 error ("%qE attribute is not supported on this platform", name); 2927 *no_add_attrs = true; 2928 return NULL_TREE; 2929 } 2930 } 2931 2932 /* Return a new PTRMEM_CST of the indicated TYPE. The MEMBER is the 2933 thing pointed to by the constant. */ 2934 2935 tree 2936 make_ptrmem_cst (tree type, tree member) 2937 { 2938 tree ptrmem_cst = make_node (PTRMEM_CST); 2939 TREE_TYPE (ptrmem_cst) = type; 2940 PTRMEM_CST_MEMBER (ptrmem_cst) = member; 2941 return ptrmem_cst; 2942 } 2943 2944 /* Build a variant of TYPE that has the indicated ATTRIBUTES. May 2945 return an existing type if an appropriate type already exists. */ 2946 2947 tree 2948 cp_build_type_attribute_variant (tree type, tree attributes) 2949 { 2950 tree new_type; 2951 2952 new_type = build_type_attribute_variant (type, attributes); 2953 if (TREE_CODE (new_type) == FUNCTION_TYPE 2954 || TREE_CODE (new_type) == METHOD_TYPE) 2955 new_type = build_exception_variant (new_type, 2956 TYPE_RAISES_EXCEPTIONS (type)); 2957 2958 /* Making a new main variant of a class type is broken. */ 2959 gcc_assert (!CLASS_TYPE_P (type) || new_type == type); 2960 2961 return new_type; 2962 } 2963 2964 /* Return TRUE if TYPE1 and TYPE2 are identical for type hashing purposes. 2965 Called only after doing all language independent checks. Only 2966 to check TYPE_RAISES_EXCEPTIONS for FUNCTION_TYPE, the rest is already 2967 compared in type_hash_eq. */ 2968 2969 bool 2970 cxx_type_hash_eq (const_tree typea, const_tree typeb) 2971 { 2972 gcc_assert (TREE_CODE (typea) == FUNCTION_TYPE 2973 || TREE_CODE (typea) == METHOD_TYPE); 2974 2975 return comp_except_specs (TYPE_RAISES_EXCEPTIONS (typea), 2976 TYPE_RAISES_EXCEPTIONS (typeb), ce_exact); 2977 } 2978 2979 /* Apply FUNC to all language-specific sub-trees of TP in a pre-order 2980 traversal. Called from walk_tree. */ 2981 2982 tree 2983 cp_walk_subtrees (tree *tp, int *walk_subtrees_p, walk_tree_fn func, 2984 void *data, struct pointer_set_t *pset) 2985 { 2986 enum tree_code code = TREE_CODE (*tp); 2987 tree result; 2988 2989 #define WALK_SUBTREE(NODE) \ 2990 do \ 2991 { \ 2992 result = cp_walk_tree (&(NODE), func, data, pset); \ 2993 if (result) goto out; \ 2994 } \ 2995 while (0) 2996 2997 /* Not one of the easy cases. We must explicitly go through the 2998 children. */ 2999 result = NULL_TREE; 3000 switch (code) 3001 { 3002 case DEFAULT_ARG: 3003 case TEMPLATE_TEMPLATE_PARM: 3004 case BOUND_TEMPLATE_TEMPLATE_PARM: 3005 case UNBOUND_CLASS_TEMPLATE: 3006 case TEMPLATE_PARM_INDEX: 3007 case TEMPLATE_TYPE_PARM: 3008 case TYPENAME_TYPE: 3009 case TYPEOF_TYPE: 3010 case UNDERLYING_TYPE: 3011 /* None of these have subtrees other than those already walked 3012 above. */ 3013 *walk_subtrees_p = 0; 3014 break; 3015 3016 case BASELINK: 3017 WALK_SUBTREE (BASELINK_FUNCTIONS (*tp)); 3018 *walk_subtrees_p = 0; 3019 break; 3020 3021 case PTRMEM_CST: 3022 WALK_SUBTREE (TREE_TYPE (*tp)); 3023 *walk_subtrees_p = 0; 3024 break; 3025 3026 case TREE_LIST: 3027 WALK_SUBTREE (TREE_PURPOSE (*tp)); 3028 break; 3029 3030 case OVERLOAD: 3031 WALK_SUBTREE (OVL_FUNCTION (*tp)); 3032 WALK_SUBTREE (OVL_CHAIN (*tp)); 3033 *walk_subtrees_p = 0; 3034 break; 3035 3036 case USING_DECL: 3037 WALK_SUBTREE (DECL_NAME (*tp)); 3038 WALK_SUBTREE (USING_DECL_SCOPE (*tp)); 3039 WALK_SUBTREE (USING_DECL_DECLS (*tp)); 3040 *walk_subtrees_p = 0; 3041 break; 3042 3043 case RECORD_TYPE: 3044 if (TYPE_PTRMEMFUNC_P (*tp)) 3045 WALK_SUBTREE (TYPE_PTRMEMFUNC_FN_TYPE (*tp)); 3046 break; 3047 3048 case TYPE_ARGUMENT_PACK: 3049 case NONTYPE_ARGUMENT_PACK: 3050 { 3051 tree args = ARGUMENT_PACK_ARGS (*tp); 3052 int i, len = TREE_VEC_LENGTH (args); 3053 for (i = 0; i < len; i++) 3054 WALK_SUBTREE (TREE_VEC_ELT (args, i)); 3055 } 3056 break; 3057 3058 case TYPE_PACK_EXPANSION: 3059 WALK_SUBTREE (TREE_TYPE (*tp)); 3060 WALK_SUBTREE (PACK_EXPANSION_EXTRA_ARGS (*tp)); 3061 *walk_subtrees_p = 0; 3062 break; 3063 3064 case EXPR_PACK_EXPANSION: 3065 WALK_SUBTREE (TREE_OPERAND (*tp, 0)); 3066 WALK_SUBTREE (PACK_EXPANSION_EXTRA_ARGS (*tp)); 3067 *walk_subtrees_p = 0; 3068 break; 3069 3070 case CAST_EXPR: 3071 case REINTERPRET_CAST_EXPR: 3072 case STATIC_CAST_EXPR: 3073 case CONST_CAST_EXPR: 3074 case DYNAMIC_CAST_EXPR: 3075 case IMPLICIT_CONV_EXPR: 3076 if (TREE_TYPE (*tp)) 3077 WALK_SUBTREE (TREE_TYPE (*tp)); 3078 3079 { 3080 int i; 3081 for (i = 0; i < TREE_CODE_LENGTH (TREE_CODE (*tp)); ++i) 3082 WALK_SUBTREE (TREE_OPERAND (*tp, i)); 3083 } 3084 *walk_subtrees_p = 0; 3085 break; 3086 3087 case TRAIT_EXPR: 3088 WALK_SUBTREE (TRAIT_EXPR_TYPE1 (*tp)); 3089 WALK_SUBTREE (TRAIT_EXPR_TYPE2 (*tp)); 3090 *walk_subtrees_p = 0; 3091 break; 3092 3093 case DECLTYPE_TYPE: 3094 WALK_SUBTREE (DECLTYPE_TYPE_EXPR (*tp)); 3095 *walk_subtrees_p = 0; 3096 break; 3097 3098 3099 default: 3100 return NULL_TREE; 3101 } 3102 3103 /* We didn't find what we were looking for. */ 3104 out: 3105 return result; 3106 3107 #undef WALK_SUBTREE 3108 } 3109 3110 /* Like save_expr, but for C++. */ 3111 3112 tree 3113 cp_save_expr (tree expr) 3114 { 3115 /* There is no reason to create a SAVE_EXPR within a template; if 3116 needed, we can create the SAVE_EXPR when instantiating the 3117 template. Furthermore, the middle-end cannot handle C++-specific 3118 tree codes. */ 3119 if (processing_template_decl) 3120 return expr; 3121 return save_expr (expr); 3122 } 3123 3124 /* Initialize tree.c. */ 3125 3126 void 3127 init_tree (void) 3128 { 3129 list_hash_table = htab_create_ggc (31, list_hash, list_hash_eq, NULL); 3130 } 3131 3132 /* Returns the kind of special function that DECL (a FUNCTION_DECL) 3133 is. Note that sfk_none is zero, so this function can be used as a 3134 predicate to test whether or not DECL is a special function. */ 3135 3136 special_function_kind 3137 special_function_p (const_tree decl) 3138 { 3139 /* Rather than doing all this stuff with magic names, we should 3140 probably have a field of type `special_function_kind' in 3141 DECL_LANG_SPECIFIC. */ 3142 if (DECL_COPY_CONSTRUCTOR_P (decl)) 3143 return sfk_copy_constructor; 3144 if (DECL_MOVE_CONSTRUCTOR_P (decl)) 3145 return sfk_move_constructor; 3146 if (DECL_CONSTRUCTOR_P (decl)) 3147 return sfk_constructor; 3148 if (DECL_OVERLOADED_OPERATOR_P (decl) == NOP_EXPR) 3149 { 3150 if (copy_fn_p (decl)) 3151 return sfk_copy_assignment; 3152 if (move_fn_p (decl)) 3153 return sfk_move_assignment; 3154 } 3155 if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (decl)) 3156 return sfk_destructor; 3157 if (DECL_COMPLETE_DESTRUCTOR_P (decl)) 3158 return sfk_complete_destructor; 3159 if (DECL_BASE_DESTRUCTOR_P (decl)) 3160 return sfk_base_destructor; 3161 if (DECL_DELETING_DESTRUCTOR_P (decl)) 3162 return sfk_deleting_destructor; 3163 if (DECL_CONV_FN_P (decl)) 3164 return sfk_conversion; 3165 3166 return sfk_none; 3167 } 3168 3169 /* Returns nonzero if TYPE is a character type, including wchar_t. */ 3170 3171 int 3172 char_type_p (tree type) 3173 { 3174 return (same_type_p (type, char_type_node) 3175 || same_type_p (type, unsigned_char_type_node) 3176 || same_type_p (type, signed_char_type_node) 3177 || same_type_p (type, char16_type_node) 3178 || same_type_p (type, char32_type_node) 3179 || same_type_p (type, wchar_type_node)); 3180 } 3181 3182 /* Returns the kind of linkage associated with the indicated DECL. Th 3183 value returned is as specified by the language standard; it is 3184 independent of implementation details regarding template 3185 instantiation, etc. For example, it is possible that a declaration 3186 to which this function assigns external linkage would not show up 3187 as a global symbol when you run `nm' on the resulting object file. */ 3188 3189 linkage_kind 3190 decl_linkage (tree decl) 3191 { 3192 /* This function doesn't attempt to calculate the linkage from first 3193 principles as given in [basic.link]. Instead, it makes use of 3194 the fact that we have already set TREE_PUBLIC appropriately, and 3195 then handles a few special cases. Ideally, we would calculate 3196 linkage first, and then transform that into a concrete 3197 implementation. */ 3198 3199 /* Things that don't have names have no linkage. */ 3200 if (!DECL_NAME (decl)) 3201 return lk_none; 3202 3203 /* Fields have no linkage. */ 3204 if (TREE_CODE (decl) == FIELD_DECL) 3205 return lk_none; 3206 3207 /* Things that are TREE_PUBLIC have external linkage. */ 3208 if (TREE_PUBLIC (decl)) 3209 return lk_external; 3210 3211 if (TREE_CODE (decl) == NAMESPACE_DECL) 3212 return lk_external; 3213 3214 /* Linkage of a CONST_DECL depends on the linkage of the enumeration 3215 type. */ 3216 if (TREE_CODE (decl) == CONST_DECL) 3217 return decl_linkage (TYPE_NAME (TREE_TYPE (decl))); 3218 3219 /* Some things that are not TREE_PUBLIC have external linkage, too. 3220 For example, on targets that don't have weak symbols, we make all 3221 template instantiations have internal linkage (in the object 3222 file), but the symbols should still be treated as having external 3223 linkage from the point of view of the language. */ 3224 if ((TREE_CODE (decl) == FUNCTION_DECL 3225 || TREE_CODE (decl) == VAR_DECL) 3226 && DECL_COMDAT (decl)) 3227 return lk_external; 3228 3229 /* Things in local scope do not have linkage, if they don't have 3230 TREE_PUBLIC set. */ 3231 if (decl_function_context (decl)) 3232 return lk_none; 3233 3234 /* Members of the anonymous namespace also have TREE_PUBLIC unset, but 3235 are considered to have external linkage for language purposes. DECLs 3236 really meant to have internal linkage have DECL_THIS_STATIC set. */ 3237 if (TREE_CODE (decl) == TYPE_DECL) 3238 return lk_external; 3239 if (TREE_CODE (decl) == VAR_DECL || TREE_CODE (decl) == FUNCTION_DECL) 3240 { 3241 if (!DECL_THIS_STATIC (decl)) 3242 return lk_external; 3243 3244 /* Static data members and static member functions from classes 3245 in anonymous namespace also don't have TREE_PUBLIC set. */ 3246 if (DECL_CLASS_CONTEXT (decl)) 3247 return lk_external; 3248 } 3249 3250 /* Everything else has internal linkage. */ 3251 return lk_internal; 3252 } 3253 3254 /* Returns the storage duration of the object or reference associated with 3255 the indicated DECL, which should be a VAR_DECL or PARM_DECL. */ 3256 3257 duration_kind 3258 decl_storage_duration (tree decl) 3259 { 3260 if (TREE_CODE (decl) == PARM_DECL) 3261 return dk_auto; 3262 if (TREE_CODE (decl) == FUNCTION_DECL) 3263 return dk_static; 3264 gcc_assert (TREE_CODE (decl) == VAR_DECL); 3265 if (!TREE_STATIC (decl) 3266 && !DECL_EXTERNAL (decl)) 3267 return dk_auto; 3268 if (DECL_THREAD_LOCAL_P (decl)) 3269 return dk_thread; 3270 return dk_static; 3271 } 3272 3273 /* EXP is an expression that we want to pre-evaluate. Returns (in 3274 *INITP) an expression that will perform the pre-evaluation. The 3275 value returned by this function is a side-effect free expression 3276 equivalent to the pre-evaluated expression. Callers must ensure 3277 that *INITP is evaluated before EXP. */ 3278 3279 tree 3280 stabilize_expr (tree exp, tree* initp) 3281 { 3282 tree init_expr; 3283 3284 if (!TREE_SIDE_EFFECTS (exp)) 3285 init_expr = NULL_TREE; 3286 else if (VOID_TYPE_P (TREE_TYPE (exp))) 3287 { 3288 *initp = exp; 3289 return void_zero_node; 3290 } 3291 /* There are no expressions with REFERENCE_TYPE, but there can be call 3292 arguments with such a type; just treat it as a pointer. */ 3293 else if (TREE_CODE (TREE_TYPE (exp)) == REFERENCE_TYPE 3294 || SCALAR_TYPE_P (TREE_TYPE (exp)) 3295 || !lvalue_or_rvalue_with_address_p (exp)) 3296 { 3297 init_expr = get_target_expr (exp); 3298 exp = TARGET_EXPR_SLOT (init_expr); 3299 } 3300 else 3301 { 3302 bool xval = !real_lvalue_p (exp); 3303 exp = cp_build_addr_expr (exp, tf_warning_or_error); 3304 init_expr = get_target_expr (exp); 3305 exp = TARGET_EXPR_SLOT (init_expr); 3306 exp = cp_build_indirect_ref (exp, RO_NULL, tf_warning_or_error); 3307 if (xval) 3308 exp = move (exp); 3309 } 3310 *initp = init_expr; 3311 3312 gcc_assert (!TREE_SIDE_EFFECTS (exp)); 3313 return exp; 3314 } 3315 3316 /* Add NEW_EXPR, an expression whose value we don't care about, after the 3317 similar expression ORIG. */ 3318 3319 tree 3320 add_stmt_to_compound (tree orig, tree new_expr) 3321 { 3322 if (!new_expr || !TREE_SIDE_EFFECTS (new_expr)) 3323 return orig; 3324 if (!orig || !TREE_SIDE_EFFECTS (orig)) 3325 return new_expr; 3326 return build2 (COMPOUND_EXPR, void_type_node, orig, new_expr); 3327 } 3328 3329 /* Like stabilize_expr, but for a call whose arguments we want to 3330 pre-evaluate. CALL is modified in place to use the pre-evaluated 3331 arguments, while, upon return, *INITP contains an expression to 3332 compute the arguments. */ 3333 3334 void 3335 stabilize_call (tree call, tree *initp) 3336 { 3337 tree inits = NULL_TREE; 3338 int i; 3339 int nargs = call_expr_nargs (call); 3340 3341 if (call == error_mark_node || processing_template_decl) 3342 { 3343 *initp = NULL_TREE; 3344 return; 3345 } 3346 3347 gcc_assert (TREE_CODE (call) == CALL_EXPR); 3348 3349 for (i = 0; i < nargs; i++) 3350 { 3351 tree init; 3352 CALL_EXPR_ARG (call, i) = 3353 stabilize_expr (CALL_EXPR_ARG (call, i), &init); 3354 inits = add_stmt_to_compound (inits, init); 3355 } 3356 3357 *initp = inits; 3358 } 3359 3360 /* Like stabilize_expr, but for an AGGR_INIT_EXPR whose arguments we want 3361 to pre-evaluate. CALL is modified in place to use the pre-evaluated 3362 arguments, while, upon return, *INITP contains an expression to 3363 compute the arguments. */ 3364 3365 void 3366 stabilize_aggr_init (tree call, tree *initp) 3367 { 3368 tree inits = NULL_TREE; 3369 int i; 3370 int nargs = aggr_init_expr_nargs (call); 3371 3372 if (call == error_mark_node) 3373 return; 3374 3375 gcc_assert (TREE_CODE (call) == AGGR_INIT_EXPR); 3376 3377 for (i = 0; i < nargs; i++) 3378 { 3379 tree init; 3380 AGGR_INIT_EXPR_ARG (call, i) = 3381 stabilize_expr (AGGR_INIT_EXPR_ARG (call, i), &init); 3382 inits = add_stmt_to_compound (inits, init); 3383 } 3384 3385 *initp = inits; 3386 } 3387 3388 /* Like stabilize_expr, but for an initialization. 3389 3390 If the initialization is for an object of class type, this function 3391 takes care not to introduce additional temporaries. 3392 3393 Returns TRUE iff the expression was successfully pre-evaluated, 3394 i.e., if INIT is now side-effect free, except for, possible, a 3395 single call to a constructor. */ 3396 3397 bool 3398 stabilize_init (tree init, tree *initp) 3399 { 3400 tree t = init; 3401 3402 *initp = NULL_TREE; 3403 3404 if (t == error_mark_node || processing_template_decl) 3405 return true; 3406 3407 if (TREE_CODE (t) == INIT_EXPR 3408 && TREE_CODE (TREE_OPERAND (t, 1)) != TARGET_EXPR 3409 && TREE_CODE (TREE_OPERAND (t, 1)) != CONSTRUCTOR 3410 && TREE_CODE (TREE_OPERAND (t, 1)) != AGGR_INIT_EXPR) 3411 { 3412 TREE_OPERAND (t, 1) = stabilize_expr (TREE_OPERAND (t, 1), initp); 3413 return true; 3414 } 3415 3416 if (TREE_CODE (t) == INIT_EXPR) 3417 t = TREE_OPERAND (t, 1); 3418 if (TREE_CODE (t) == TARGET_EXPR) 3419 t = TARGET_EXPR_INITIAL (t); 3420 if (TREE_CODE (t) == COMPOUND_EXPR) 3421 t = expr_last (t); 3422 if (TREE_CODE (t) == CONSTRUCTOR) 3423 { 3424 /* Aggregate initialization: stabilize each of the field 3425 initializers. */ 3426 unsigned i; 3427 constructor_elt *ce; 3428 bool good = true; 3429 VEC(constructor_elt,gc) *v = CONSTRUCTOR_ELTS (t); 3430 for (i = 0; VEC_iterate (constructor_elt, v, i, ce); ++i) 3431 { 3432 tree type = TREE_TYPE (ce->value); 3433 tree subinit; 3434 if (TREE_CODE (type) == REFERENCE_TYPE 3435 || SCALAR_TYPE_P (type)) 3436 ce->value = stabilize_expr (ce->value, &subinit); 3437 else if (!stabilize_init (ce->value, &subinit)) 3438 good = false; 3439 *initp = add_stmt_to_compound (*initp, subinit); 3440 } 3441 return good; 3442 } 3443 3444 /* If the initializer is a COND_EXPR, we can't preevaluate 3445 anything. */ 3446 if (TREE_CODE (t) == COND_EXPR) 3447 return false; 3448 3449 if (TREE_CODE (t) == CALL_EXPR) 3450 { 3451 stabilize_call (t, initp); 3452 return true; 3453 } 3454 3455 if (TREE_CODE (t) == AGGR_INIT_EXPR) 3456 { 3457 stabilize_aggr_init (t, initp); 3458 return true; 3459 } 3460 3461 /* The initialization is being performed via a bitwise copy -- and 3462 the item copied may have side effects. */ 3463 return !TREE_SIDE_EFFECTS (init); 3464 } 3465 3466 /* Like "fold", but should be used whenever we might be processing the 3467 body of a template. */ 3468 3469 tree 3470 fold_if_not_in_template (tree expr) 3471 { 3472 /* In the body of a template, there is never any need to call 3473 "fold". We will call fold later when actually instantiating the 3474 template. Integral constant expressions in templates will be 3475 evaluated via fold_non_dependent_expr, as necessary. */ 3476 if (processing_template_decl) 3477 return expr; 3478 3479 /* Fold C++ front-end specific tree codes. */ 3480 if (TREE_CODE (expr) == UNARY_PLUS_EXPR) 3481 return fold_convert (TREE_TYPE (expr), TREE_OPERAND (expr, 0)); 3482 3483 return fold (expr); 3484 } 3485 3486 /* Returns true if a cast to TYPE may appear in an integral constant 3487 expression. */ 3488 3489 bool 3490 cast_valid_in_integral_constant_expression_p (tree type) 3491 { 3492 return (INTEGRAL_OR_ENUMERATION_TYPE_P (type) 3493 || cxx_dialect >= cxx0x 3494 || dependent_type_p (type) 3495 || type == error_mark_node); 3496 } 3497 3498 /* Return true if we need to fix linkage information of DECL. */ 3499 3500 static bool 3501 cp_fix_function_decl_p (tree decl) 3502 { 3503 /* Skip if DECL is not externally visible. */ 3504 if (!TREE_PUBLIC (decl)) 3505 return false; 3506 3507 /* We need to fix DECL if it a appears to be exported but with no 3508 function body. Thunks do not have CFGs and we may need to 3509 handle them specially later. */ 3510 if (!gimple_has_body_p (decl) 3511 && !DECL_THUNK_P (decl) 3512 && !DECL_EXTERNAL (decl)) 3513 { 3514 struct cgraph_node *node = cgraph_get_node (decl); 3515 3516 /* Don't fix same_body aliases. Although they don't have their own 3517 CFG, they share it with what they alias to. */ 3518 if (!node || !node->alias 3519 || !VEC_length (ipa_ref_t, node->ref_list.references)) 3520 return true; 3521 } 3522 3523 return false; 3524 } 3525 3526 /* Clean the C++ specific parts of the tree T. */ 3527 3528 void 3529 cp_free_lang_data (tree t) 3530 { 3531 if (TREE_CODE (t) == METHOD_TYPE 3532 || TREE_CODE (t) == FUNCTION_TYPE) 3533 { 3534 /* Default args are not interesting anymore. */ 3535 tree argtypes = TYPE_ARG_TYPES (t); 3536 while (argtypes) 3537 { 3538 TREE_PURPOSE (argtypes) = 0; 3539 argtypes = TREE_CHAIN (argtypes); 3540 } 3541 } 3542 else if (TREE_CODE (t) == FUNCTION_DECL 3543 && cp_fix_function_decl_p (t)) 3544 { 3545 /* If T is used in this translation unit at all, the definition 3546 must exist somewhere else since we have decided to not emit it 3547 in this TU. So make it an external reference. */ 3548 DECL_EXTERNAL (t) = 1; 3549 TREE_STATIC (t) = 0; 3550 } 3551 if (TREE_CODE (t) == NAMESPACE_DECL) 3552 { 3553 /* The list of users of a namespace isn't useful for the middle-end 3554 or debug generators. */ 3555 DECL_NAMESPACE_USERS (t) = NULL_TREE; 3556 /* Neither do we need the leftover chaining of namespaces 3557 from the binding level. */ 3558 DECL_CHAIN (t) = NULL_TREE; 3559 } 3560 } 3561 3562 /* Stub for c-common. Please keep in sync with c-decl.c. 3563 FIXME: If address space support is target specific, then this 3564 should be a C target hook. But currently this is not possible, 3565 because this function is called via REGISTER_TARGET_PRAGMAS. */ 3566 void 3567 c_register_addr_space (const char *word ATTRIBUTE_UNUSED, 3568 addr_space_t as ATTRIBUTE_UNUSED) 3569 { 3570 } 3571 3572 /* Return the number of operands in T that we care about for things like 3573 mangling. */ 3574 3575 int 3576 cp_tree_operand_length (const_tree t) 3577 { 3578 enum tree_code code = TREE_CODE (t); 3579 3580 switch (code) 3581 { 3582 case PREINCREMENT_EXPR: 3583 case PREDECREMENT_EXPR: 3584 case POSTINCREMENT_EXPR: 3585 case POSTDECREMENT_EXPR: 3586 return 1; 3587 3588 case ARRAY_REF: 3589 return 2; 3590 3591 case EXPR_PACK_EXPANSION: 3592 return 1; 3593 3594 default: 3595 return TREE_OPERAND_LENGTH (t); 3596 } 3597 } 3598 3599 #if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007) 3600 /* Complain that some language-specific thing hanging off a tree 3601 node has been accessed improperly. */ 3602 3603 void 3604 lang_check_failed (const char* file, int line, const char* function) 3605 { 3606 internal_error ("lang_* check: failed in %s, at %s:%d", 3607 function, trim_filename (file), line); 3608 } 3609 #endif /* ENABLE_TREE_CHECKING */ 3610 3611 #include "gt-cp-tree.h" 3612