1 /* Definitions for C++ name lookup routines. 2 Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012 3 Free Software Foundation, Inc. 4 Contributed by Gabriel Dos Reis <gdr@integrable-solutions.net> 5 6 This file is part of GCC. 7 8 GCC is free software; you can redistribute it and/or modify 9 it under the terms of the GNU General Public License as published by 10 the Free Software Foundation; either version 3, or (at your option) 11 any later version. 12 13 GCC is distributed in the hope that it will be useful, 14 but WITHOUT ANY WARRANTY; without even the implied warranty of 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 16 GNU General Public License for more details. 17 18 You should have received a copy of the GNU General Public License 19 along with GCC; see the file COPYING3. If not see 20 <http://www.gnu.org/licenses/>. */ 21 22 #include "config.h" 23 #include "system.h" 24 #include "coretypes.h" 25 #include "tm.h" 26 #include "flags.h" 27 #include "tree.h" 28 #include "cp-tree.h" 29 #include "name-lookup.h" 30 #include "timevar.h" 31 #include "diagnostic-core.h" 32 #include "intl.h" 33 #include "debug.h" 34 #include "c-family/c-pragma.h" 35 #include "params.h" 36 #include "pointer-set.h" 37 38 /* The bindings for a particular name in a particular scope. */ 39 40 struct scope_binding { 41 tree value; 42 tree type; 43 }; 44 #define EMPTY_SCOPE_BINDING { NULL_TREE, NULL_TREE } 45 46 static cp_binding_level *innermost_nonclass_level (void); 47 static cxx_binding *binding_for_name (cp_binding_level *, tree); 48 static tree push_overloaded_decl (tree, int, bool); 49 static bool lookup_using_namespace (tree, struct scope_binding *, tree, 50 tree, int); 51 static bool qualified_lookup_using_namespace (tree, tree, 52 struct scope_binding *, int); 53 static tree lookup_type_current_level (tree); 54 static tree push_using_directive (tree); 55 static tree lookup_extern_c_fun_in_all_ns (tree); 56 static void diagnose_name_conflict (tree, tree); 57 58 /* The :: namespace. */ 59 60 tree global_namespace; 61 62 /* The name of the anonymous namespace, throughout this translation 63 unit. */ 64 static GTY(()) tree anonymous_namespace_name; 65 66 /* Initialize anonymous_namespace_name if necessary, and return it. */ 67 68 static tree 69 get_anonymous_namespace_name (void) 70 { 71 if (!anonymous_namespace_name) 72 { 73 /* The anonymous namespace has to have a unique name 74 if typeinfo objects are being compared by name. */ 75 if (! flag_weak || ! SUPPORTS_ONE_ONLY) 76 anonymous_namespace_name = get_file_function_name ("N"); 77 else 78 /* The demangler expects anonymous namespaces to be called 79 something starting with '_GLOBAL__N_'. */ 80 anonymous_namespace_name = get_identifier ("_GLOBAL__N_1"); 81 } 82 return anonymous_namespace_name; 83 } 84 85 /* Compute the chain index of a binding_entry given the HASH value of its 86 name and the total COUNT of chains. COUNT is assumed to be a power 87 of 2. */ 88 89 #define ENTRY_INDEX(HASH, COUNT) (((HASH) >> 3) & ((COUNT) - 1)) 90 91 /* A free list of "binding_entry"s awaiting for re-use. */ 92 93 static GTY((deletable)) binding_entry free_binding_entry = NULL; 94 95 /* Create a binding_entry object for (NAME, TYPE). */ 96 97 static inline binding_entry 98 binding_entry_make (tree name, tree type) 99 { 100 binding_entry entry; 101 102 if (free_binding_entry) 103 { 104 entry = free_binding_entry; 105 free_binding_entry = entry->chain; 106 } 107 else 108 entry = ggc_alloc_binding_entry_s (); 109 110 entry->name = name; 111 entry->type = type; 112 entry->chain = NULL; 113 114 return entry; 115 } 116 117 /* Put ENTRY back on the free list. */ 118 #if 0 119 static inline void 120 binding_entry_free (binding_entry entry) 121 { 122 entry->name = NULL; 123 entry->type = NULL; 124 entry->chain = free_binding_entry; 125 free_binding_entry = entry; 126 } 127 #endif 128 129 /* The datatype used to implement the mapping from names to types at 130 a given scope. */ 131 struct GTY(()) binding_table_s { 132 /* Array of chains of "binding_entry"s */ 133 binding_entry * GTY((length ("%h.chain_count"))) chain; 134 135 /* The number of chains in this table. This is the length of the 136 member "chain" considered as an array. */ 137 size_t chain_count; 138 139 /* Number of "binding_entry"s in this table. */ 140 size_t entry_count; 141 }; 142 143 /* Construct TABLE with an initial CHAIN_COUNT. */ 144 145 static inline void 146 binding_table_construct (binding_table table, size_t chain_count) 147 { 148 table->chain_count = chain_count; 149 table->entry_count = 0; 150 table->chain = ggc_alloc_cleared_vec_binding_entry (table->chain_count); 151 } 152 153 /* Make TABLE's entries ready for reuse. */ 154 #if 0 155 static void 156 binding_table_free (binding_table table) 157 { 158 size_t i; 159 size_t count; 160 161 if (table == NULL) 162 return; 163 164 for (i = 0, count = table->chain_count; i < count; ++i) 165 { 166 binding_entry temp = table->chain[i]; 167 while (temp != NULL) 168 { 169 binding_entry entry = temp; 170 temp = entry->chain; 171 binding_entry_free (entry); 172 } 173 table->chain[i] = NULL; 174 } 175 table->entry_count = 0; 176 } 177 #endif 178 179 /* Allocate a table with CHAIN_COUNT, assumed to be a power of two. */ 180 181 static inline binding_table 182 binding_table_new (size_t chain_count) 183 { 184 binding_table table = ggc_alloc_binding_table_s (); 185 table->chain = NULL; 186 binding_table_construct (table, chain_count); 187 return table; 188 } 189 190 /* Expand TABLE to twice its current chain_count. */ 191 192 static void 193 binding_table_expand (binding_table table) 194 { 195 const size_t old_chain_count = table->chain_count; 196 const size_t old_entry_count = table->entry_count; 197 const size_t new_chain_count = 2 * old_chain_count; 198 binding_entry *old_chains = table->chain; 199 size_t i; 200 201 binding_table_construct (table, new_chain_count); 202 for (i = 0; i < old_chain_count; ++i) 203 { 204 binding_entry entry = old_chains[i]; 205 for (; entry != NULL; entry = old_chains[i]) 206 { 207 const unsigned int hash = IDENTIFIER_HASH_VALUE (entry->name); 208 const size_t j = ENTRY_INDEX (hash, new_chain_count); 209 210 old_chains[i] = entry->chain; 211 entry->chain = table->chain[j]; 212 table->chain[j] = entry; 213 } 214 } 215 table->entry_count = old_entry_count; 216 } 217 218 /* Insert a binding for NAME to TYPE into TABLE. */ 219 220 static void 221 binding_table_insert (binding_table table, tree name, tree type) 222 { 223 const unsigned int hash = IDENTIFIER_HASH_VALUE (name); 224 const size_t i = ENTRY_INDEX (hash, table->chain_count); 225 binding_entry entry = binding_entry_make (name, type); 226 227 entry->chain = table->chain[i]; 228 table->chain[i] = entry; 229 ++table->entry_count; 230 231 if (3 * table->chain_count < 5 * table->entry_count) 232 binding_table_expand (table); 233 } 234 235 /* Return the binding_entry, if any, that maps NAME. */ 236 237 binding_entry 238 binding_table_find (binding_table table, tree name) 239 { 240 const unsigned int hash = IDENTIFIER_HASH_VALUE (name); 241 binding_entry entry = table->chain[ENTRY_INDEX (hash, table->chain_count)]; 242 243 while (entry != NULL && entry->name != name) 244 entry = entry->chain; 245 246 return entry; 247 } 248 249 /* Apply PROC -- with DATA -- to all entries in TABLE. */ 250 251 void 252 binding_table_foreach (binding_table table, bt_foreach_proc proc, void *data) 253 { 254 size_t chain_count; 255 size_t i; 256 257 if (!table) 258 return; 259 260 chain_count = table->chain_count; 261 for (i = 0; i < chain_count; ++i) 262 { 263 binding_entry entry = table->chain[i]; 264 for (; entry != NULL; entry = entry->chain) 265 proc (entry, data); 266 } 267 } 268 269 #ifndef ENABLE_SCOPE_CHECKING 270 # define ENABLE_SCOPE_CHECKING 0 271 #else 272 # define ENABLE_SCOPE_CHECKING 1 273 #endif 274 275 /* A free list of "cxx_binding"s, connected by their PREVIOUS. */ 276 277 static GTY((deletable)) cxx_binding *free_bindings; 278 279 /* Initialize VALUE and TYPE field for BINDING, and set the PREVIOUS 280 field to NULL. */ 281 282 static inline void 283 cxx_binding_init (cxx_binding *binding, tree value, tree type) 284 { 285 binding->value = value; 286 binding->type = type; 287 binding->previous = NULL; 288 } 289 290 /* (GC)-allocate a binding object with VALUE and TYPE member initialized. */ 291 292 static cxx_binding * 293 cxx_binding_make (tree value, tree type) 294 { 295 cxx_binding *binding; 296 if (free_bindings) 297 { 298 binding = free_bindings; 299 free_bindings = binding->previous; 300 } 301 else 302 binding = ggc_alloc_cxx_binding (); 303 304 cxx_binding_init (binding, value, type); 305 306 return binding; 307 } 308 309 /* Put BINDING back on the free list. */ 310 311 static inline void 312 cxx_binding_free (cxx_binding *binding) 313 { 314 binding->scope = NULL; 315 binding->previous = free_bindings; 316 free_bindings = binding; 317 } 318 319 /* Create a new binding for NAME (with the indicated VALUE and TYPE 320 bindings) in the class scope indicated by SCOPE. */ 321 322 static cxx_binding * 323 new_class_binding (tree name, tree value, tree type, cp_binding_level *scope) 324 { 325 cp_class_binding *cb; 326 cxx_binding *binding; 327 328 cb = VEC_safe_push (cp_class_binding, gc, scope->class_shadowed, NULL); 329 330 cb->identifier = name; 331 cb->base = binding = cxx_binding_make (value, type); 332 binding->scope = scope; 333 return binding; 334 } 335 336 /* Make DECL the innermost binding for ID. The LEVEL is the binding 337 level at which this declaration is being bound. */ 338 339 static void 340 push_binding (tree id, tree decl, cp_binding_level* level) 341 { 342 cxx_binding *binding; 343 344 if (level != class_binding_level) 345 { 346 binding = cxx_binding_make (decl, NULL_TREE); 347 binding->scope = level; 348 } 349 else 350 binding = new_class_binding (id, decl, /*type=*/NULL_TREE, level); 351 352 /* Now, fill in the binding information. */ 353 binding->previous = IDENTIFIER_BINDING (id); 354 INHERITED_VALUE_BINDING_P (binding) = 0; 355 LOCAL_BINDING_P (binding) = (level != class_binding_level); 356 357 /* And put it on the front of the list of bindings for ID. */ 358 IDENTIFIER_BINDING (id) = binding; 359 } 360 361 /* Remove the binding for DECL which should be the innermost binding 362 for ID. */ 363 364 void 365 pop_binding (tree id, tree decl) 366 { 367 cxx_binding *binding; 368 369 if (id == NULL_TREE) 370 /* It's easiest to write the loops that call this function without 371 checking whether or not the entities involved have names. We 372 get here for such an entity. */ 373 return; 374 375 /* Get the innermost binding for ID. */ 376 binding = IDENTIFIER_BINDING (id); 377 378 /* The name should be bound. */ 379 gcc_assert (binding != NULL); 380 381 /* The DECL will be either the ordinary binding or the type 382 binding for this identifier. Remove that binding. */ 383 if (binding->value == decl) 384 binding->value = NULL_TREE; 385 else 386 { 387 gcc_assert (binding->type == decl); 388 binding->type = NULL_TREE; 389 } 390 391 if (!binding->value && !binding->type) 392 { 393 /* We're completely done with the innermost binding for this 394 identifier. Unhook it from the list of bindings. */ 395 IDENTIFIER_BINDING (id) = binding->previous; 396 397 /* Add it to the free list. */ 398 cxx_binding_free (binding); 399 } 400 } 401 402 /* Strip non dependent using declarations. If DECL is dependent, 403 surreptitiously create a typename_type and return it. */ 404 405 tree 406 strip_using_decl (tree decl) 407 { 408 if (decl == NULL_TREE) 409 return NULL_TREE; 410 411 while (TREE_CODE (decl) == USING_DECL && !DECL_DEPENDENT_P (decl)) 412 decl = USING_DECL_DECLS (decl); 413 414 if (TREE_CODE (decl) == USING_DECL && DECL_DEPENDENT_P (decl) 415 && USING_DECL_TYPENAME_P (decl)) 416 { 417 /* We have found a type introduced by a using 418 declaration at class scope that refers to a dependent 419 type. 420 421 using typename :: [opt] nested-name-specifier unqualified-id ; 422 */ 423 decl = make_typename_type (TREE_TYPE (decl), 424 DECL_NAME (decl), 425 typename_type, tf_error); 426 if (decl != error_mark_node) 427 decl = TYPE_NAME (decl); 428 } 429 430 return decl; 431 } 432 433 /* BINDING records an existing declaration for a name in the current scope. 434 But, DECL is another declaration for that same identifier in the 435 same scope. This is the `struct stat' hack whereby a non-typedef 436 class name or enum-name can be bound at the same level as some other 437 kind of entity. 438 3.3.7/1 439 440 A class name (9.1) or enumeration name (7.2) can be hidden by the 441 name of an object, function, or enumerator declared in the same scope. 442 If a class or enumeration name and an object, function, or enumerator 443 are declared in the same scope (in any order) with the same name, the 444 class or enumeration name is hidden wherever the object, function, or 445 enumerator name is visible. 446 447 It's the responsibility of the caller to check that 448 inserting this name is valid here. Returns nonzero if the new binding 449 was successful. */ 450 451 static bool 452 supplement_binding_1 (cxx_binding *binding, tree decl) 453 { 454 tree bval = binding->value; 455 bool ok = true; 456 tree target_bval = strip_using_decl (bval); 457 tree target_decl = strip_using_decl (decl); 458 459 if (TREE_CODE (target_decl) == TYPE_DECL && DECL_ARTIFICIAL (target_decl) 460 && target_decl != target_bval 461 && (TREE_CODE (target_bval) != TYPE_DECL 462 /* We allow pushing an enum multiple times in a class 463 template in order to handle late matching of underlying 464 type on an opaque-enum-declaration followed by an 465 enum-specifier. */ 466 || (TREE_CODE (TREE_TYPE (target_decl)) == ENUMERAL_TYPE 467 && TREE_CODE (TREE_TYPE (target_bval)) == ENUMERAL_TYPE 468 && (dependent_type_p (ENUM_UNDERLYING_TYPE 469 (TREE_TYPE (target_decl))) 470 || dependent_type_p (ENUM_UNDERLYING_TYPE 471 (TREE_TYPE (target_bval))))))) 472 /* The new name is the type name. */ 473 binding->type = decl; 474 else if (/* TARGET_BVAL is null when push_class_level_binding moves 475 an inherited type-binding out of the way to make room 476 for a new value binding. */ 477 !target_bval 478 /* TARGET_BVAL is error_mark_node when TARGET_DECL's name 479 has been used in a non-class scope prior declaration. 480 In that case, we should have already issued a 481 diagnostic; for graceful error recovery purpose, pretend 482 this was the intended declaration for that name. */ 483 || target_bval == error_mark_node 484 /* If TARGET_BVAL is anticipated but has not yet been 485 declared, pretend it is not there at all. */ 486 || (TREE_CODE (target_bval) == FUNCTION_DECL 487 && DECL_ANTICIPATED (target_bval) 488 && !DECL_HIDDEN_FRIEND_P (target_bval))) 489 binding->value = decl; 490 else if (TREE_CODE (target_bval) == TYPE_DECL 491 && DECL_ARTIFICIAL (target_bval) 492 && target_decl != target_bval 493 && (TREE_CODE (target_decl) != TYPE_DECL 494 || same_type_p (TREE_TYPE (target_decl), 495 TREE_TYPE (target_bval)))) 496 { 497 /* The old binding was a type name. It was placed in 498 VALUE field because it was thought, at the point it was 499 declared, to be the only entity with such a name. Move the 500 type name into the type slot; it is now hidden by the new 501 binding. */ 502 binding->type = bval; 503 binding->value = decl; 504 binding->value_is_inherited = false; 505 } 506 else if (TREE_CODE (target_bval) == TYPE_DECL 507 && TREE_CODE (target_decl) == TYPE_DECL 508 && DECL_NAME (target_decl) == DECL_NAME (target_bval) 509 && binding->scope->kind != sk_class 510 && (same_type_p (TREE_TYPE (target_decl), TREE_TYPE (target_bval)) 511 /* If either type involves template parameters, we must 512 wait until instantiation. */ 513 || uses_template_parms (TREE_TYPE (target_decl)) 514 || uses_template_parms (TREE_TYPE (target_bval)))) 515 /* We have two typedef-names, both naming the same type to have 516 the same name. In general, this is OK because of: 517 518 [dcl.typedef] 519 520 In a given scope, a typedef specifier can be used to redefine 521 the name of any type declared in that scope to refer to the 522 type to which it already refers. 523 524 However, in class scopes, this rule does not apply due to the 525 stricter language in [class.mem] prohibiting redeclarations of 526 members. */ 527 ok = false; 528 /* There can be two block-scope declarations of the same variable, 529 so long as they are `extern' declarations. However, there cannot 530 be two declarations of the same static data member: 531 532 [class.mem] 533 534 A member shall not be declared twice in the 535 member-specification. */ 536 else if (TREE_CODE (target_decl) == VAR_DECL 537 && TREE_CODE (target_bval) == VAR_DECL 538 && DECL_EXTERNAL (target_decl) && DECL_EXTERNAL (target_bval) 539 && !DECL_CLASS_SCOPE_P (target_decl)) 540 { 541 duplicate_decls (decl, binding->value, /*newdecl_is_friend=*/false); 542 ok = false; 543 } 544 else if (TREE_CODE (decl) == NAMESPACE_DECL 545 && TREE_CODE (bval) == NAMESPACE_DECL 546 && DECL_NAMESPACE_ALIAS (decl) 547 && DECL_NAMESPACE_ALIAS (bval) 548 && ORIGINAL_NAMESPACE (bval) == ORIGINAL_NAMESPACE (decl)) 549 /* [namespace.alias] 550 551 In a declarative region, a namespace-alias-definition can be 552 used to redefine a namespace-alias declared in that declarative 553 region to refer only to the namespace to which it already 554 refers. */ 555 ok = false; 556 else 557 { 558 diagnose_name_conflict (decl, bval); 559 ok = false; 560 } 561 562 return ok; 563 } 564 565 /* Diagnose a name conflict between DECL and BVAL. */ 566 567 static void 568 diagnose_name_conflict (tree decl, tree bval) 569 { 570 if (TREE_CODE (decl) == TREE_CODE (bval) 571 && (TREE_CODE (decl) != TYPE_DECL 572 || (DECL_ARTIFICIAL (decl) && DECL_ARTIFICIAL (bval)) 573 || (!DECL_ARTIFICIAL (decl) && !DECL_ARTIFICIAL (bval))) 574 && !is_overloaded_fn (decl)) 575 error ("redeclaration of %q#D", decl); 576 else 577 error ("%q#D conflicts with a previous declaration", decl); 578 579 inform (input_location, "previous declaration %q+#D", bval); 580 } 581 582 /* Wrapper for supplement_binding_1. */ 583 584 static bool 585 supplement_binding (cxx_binding *binding, tree decl) 586 { 587 bool ret; 588 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 589 ret = supplement_binding_1 (binding, decl); 590 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 591 return ret; 592 } 593 594 /* Add DECL to the list of things declared in B. */ 595 596 static void 597 add_decl_to_level (tree decl, cp_binding_level *b) 598 { 599 /* We used to record virtual tables as if they were ordinary 600 variables, but no longer do so. */ 601 gcc_assert (!(TREE_CODE (decl) == VAR_DECL && DECL_VIRTUAL_P (decl))); 602 603 if (TREE_CODE (decl) == NAMESPACE_DECL 604 && !DECL_NAMESPACE_ALIAS (decl)) 605 { 606 DECL_CHAIN (decl) = b->namespaces; 607 b->namespaces = decl; 608 } 609 else 610 { 611 /* We build up the list in reverse order, and reverse it later if 612 necessary. */ 613 TREE_CHAIN (decl) = b->names; 614 b->names = decl; 615 616 /* If appropriate, add decl to separate list of statics. We 617 include extern variables because they might turn out to be 618 static later. It's OK for this list to contain a few false 619 positives. */ 620 if (b->kind == sk_namespace) 621 if ((TREE_CODE (decl) == VAR_DECL 622 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))) 623 || (TREE_CODE (decl) == FUNCTION_DECL 624 && (!TREE_PUBLIC (decl) || DECL_DECLARED_INLINE_P (decl)))) 625 VEC_safe_push (tree, gc, b->static_decls, decl); 626 } 627 } 628 629 /* Record a decl-node X as belonging to the current lexical scope. 630 Check for errors (such as an incompatible declaration for the same 631 name already seen in the same scope). IS_FRIEND is true if X is 632 declared as a friend. 633 634 Returns either X or an old decl for the same name. 635 If an old decl is returned, it may have been smashed 636 to agree with what X says. */ 637 638 static tree 639 pushdecl_maybe_friend_1 (tree x, bool is_friend) 640 { 641 tree t; 642 tree name; 643 int need_new_binding; 644 645 if (x == error_mark_node) 646 return error_mark_node; 647 648 need_new_binding = 1; 649 650 if (DECL_TEMPLATE_PARM_P (x)) 651 /* Template parameters have no context; they are not X::T even 652 when declared within a class or namespace. */ 653 ; 654 else 655 { 656 if (current_function_decl && x != current_function_decl 657 /* A local declaration for a function doesn't constitute 658 nesting. */ 659 && TREE_CODE (x) != FUNCTION_DECL 660 /* A local declaration for an `extern' variable is in the 661 scope of the current namespace, not the current 662 function. */ 663 && !(TREE_CODE (x) == VAR_DECL && DECL_EXTERNAL (x)) 664 /* When parsing the parameter list of a function declarator, 665 don't set DECL_CONTEXT to an enclosing function. When we 666 push the PARM_DECLs in order to process the function body, 667 current_binding_level->this_entity will be set. */ 668 && !(TREE_CODE (x) == PARM_DECL 669 && current_binding_level->kind == sk_function_parms 670 && current_binding_level->this_entity == NULL) 671 && !DECL_CONTEXT (x)) 672 DECL_CONTEXT (x) = current_function_decl; 673 674 /* If this is the declaration for a namespace-scope function, 675 but the declaration itself is in a local scope, mark the 676 declaration. */ 677 if (TREE_CODE (x) == FUNCTION_DECL 678 && DECL_NAMESPACE_SCOPE_P (x) 679 && current_function_decl 680 && x != current_function_decl) 681 DECL_LOCAL_FUNCTION_P (x) = 1; 682 } 683 684 name = DECL_NAME (x); 685 if (name) 686 { 687 int different_binding_level = 0; 688 689 if (TREE_CODE (name) == TEMPLATE_ID_EXPR) 690 name = TREE_OPERAND (name, 0); 691 692 /* In case this decl was explicitly namespace-qualified, look it 693 up in its namespace context. */ 694 if (DECL_NAMESPACE_SCOPE_P (x) && namespace_bindings_p ()) 695 t = namespace_binding (name, DECL_CONTEXT (x)); 696 else 697 t = lookup_name_innermost_nonclass_level (name); 698 699 /* [basic.link] If there is a visible declaration of an entity 700 with linkage having the same name and type, ignoring entities 701 declared outside the innermost enclosing namespace scope, the 702 block scope declaration declares that same entity and 703 receives the linkage of the previous declaration. */ 704 if (! t && current_function_decl && x != current_function_decl 705 && (TREE_CODE (x) == FUNCTION_DECL || TREE_CODE (x) == VAR_DECL) 706 && DECL_EXTERNAL (x)) 707 { 708 /* Look in block scope. */ 709 t = innermost_non_namespace_value (name); 710 /* Or in the innermost namespace. */ 711 if (! t) 712 t = namespace_binding (name, DECL_CONTEXT (x)); 713 /* Does it have linkage? Note that if this isn't a DECL, it's an 714 OVERLOAD, which is OK. */ 715 if (t && DECL_P (t) && ! (TREE_STATIC (t) || DECL_EXTERNAL (t))) 716 t = NULL_TREE; 717 if (t) 718 different_binding_level = 1; 719 } 720 721 /* If we are declaring a function, and the result of name-lookup 722 was an OVERLOAD, look for an overloaded instance that is 723 actually the same as the function we are declaring. (If 724 there is one, we have to merge our declaration with the 725 previous declaration.) */ 726 if (t && TREE_CODE (t) == OVERLOAD) 727 { 728 tree match; 729 730 if (TREE_CODE (x) == FUNCTION_DECL) 731 for (match = t; match; match = OVL_NEXT (match)) 732 { 733 if (decls_match (OVL_CURRENT (match), x)) 734 break; 735 } 736 else 737 /* Just choose one. */ 738 match = t; 739 740 if (match) 741 t = OVL_CURRENT (match); 742 else 743 t = NULL_TREE; 744 } 745 746 if (t && t != error_mark_node) 747 { 748 if (different_binding_level) 749 { 750 if (decls_match (x, t)) 751 /* The standard only says that the local extern 752 inherits linkage from the previous decl; in 753 particular, default args are not shared. Add 754 the decl into a hash table to make sure only 755 the previous decl in this case is seen by the 756 middle end. */ 757 { 758 struct cxx_int_tree_map *h; 759 void **loc; 760 761 TREE_PUBLIC (x) = TREE_PUBLIC (t); 762 763 if (cp_function_chain->extern_decl_map == NULL) 764 cp_function_chain->extern_decl_map 765 = htab_create_ggc (20, cxx_int_tree_map_hash, 766 cxx_int_tree_map_eq, NULL); 767 768 h = ggc_alloc_cxx_int_tree_map (); 769 h->uid = DECL_UID (x); 770 h->to = t; 771 loc = htab_find_slot_with_hash 772 (cp_function_chain->extern_decl_map, h, 773 h->uid, INSERT); 774 *(struct cxx_int_tree_map **) loc = h; 775 } 776 } 777 else if (TREE_CODE (t) == PARM_DECL) 778 { 779 /* Check for duplicate params. */ 780 tree d = duplicate_decls (x, t, is_friend); 781 if (d) 782 return d; 783 } 784 else if ((DECL_EXTERN_C_FUNCTION_P (x) 785 || DECL_FUNCTION_TEMPLATE_P (x)) 786 && is_overloaded_fn (t)) 787 /* Don't do anything just yet. */; 788 else if (t == wchar_decl_node) 789 { 790 if (! DECL_IN_SYSTEM_HEADER (x)) 791 pedwarn (input_location, OPT_pedantic, "redeclaration of %<wchar_t%> as %qT", 792 TREE_TYPE (x)); 793 794 /* Throw away the redeclaration. */ 795 return t; 796 } 797 else 798 { 799 tree olddecl = duplicate_decls (x, t, is_friend); 800 801 /* If the redeclaration failed, we can stop at this 802 point. */ 803 if (olddecl == error_mark_node) 804 return error_mark_node; 805 806 if (olddecl) 807 { 808 if (TREE_CODE (t) == TYPE_DECL) 809 SET_IDENTIFIER_TYPE_VALUE (name, TREE_TYPE (t)); 810 811 return t; 812 } 813 else if (DECL_MAIN_P (x) && TREE_CODE (t) == FUNCTION_DECL) 814 { 815 /* A redeclaration of main, but not a duplicate of the 816 previous one. 817 818 [basic.start.main] 819 820 This function shall not be overloaded. */ 821 error ("invalid redeclaration of %q+D", t); 822 error ("as %qD", x); 823 /* We don't try to push this declaration since that 824 causes a crash. */ 825 return x; 826 } 827 } 828 } 829 830 /* If x has C linkage-specification, (extern "C"), 831 lookup its binding, in case it's already bound to an object. 832 The lookup is done in all namespaces. 833 If we find an existing binding, make sure it has the same 834 exception specification as x, otherwise, bail in error [7.5, 7.6]. */ 835 if ((TREE_CODE (x) == FUNCTION_DECL) 836 && DECL_EXTERN_C_P (x) 837 /* We should ignore declarations happening in system headers. */ 838 && !DECL_ARTIFICIAL (x) 839 && !DECL_IN_SYSTEM_HEADER (x)) 840 { 841 tree previous = lookup_extern_c_fun_in_all_ns (x); 842 if (previous 843 && !DECL_ARTIFICIAL (previous) 844 && !DECL_IN_SYSTEM_HEADER (previous) 845 && DECL_CONTEXT (previous) != DECL_CONTEXT (x)) 846 { 847 /* In case either x or previous is declared to throw an exception, 848 make sure both exception specifications are equal. */ 849 if (decls_match (x, previous)) 850 { 851 tree x_exception_spec = NULL_TREE; 852 tree previous_exception_spec = NULL_TREE; 853 854 x_exception_spec = 855 TYPE_RAISES_EXCEPTIONS (TREE_TYPE (x)); 856 previous_exception_spec = 857 TYPE_RAISES_EXCEPTIONS (TREE_TYPE (previous)); 858 if (!comp_except_specs (previous_exception_spec, 859 x_exception_spec, 860 ce_normal)) 861 { 862 pedwarn (input_location, 0, 863 "declaration of %q#D with C language linkage", 864 x); 865 pedwarn (input_location, 0, 866 "conflicts with previous declaration %q+#D", 867 previous); 868 pedwarn (input_location, 0, 869 "due to different exception specifications"); 870 return error_mark_node; 871 } 872 if (DECL_ASSEMBLER_NAME_SET_P (previous)) 873 SET_DECL_ASSEMBLER_NAME (x, 874 DECL_ASSEMBLER_NAME (previous)); 875 } 876 else 877 { 878 pedwarn (input_location, 0, 879 "declaration of %q#D with C language linkage", x); 880 pedwarn (input_location, 0, 881 "conflicts with previous declaration %q+#D", 882 previous); 883 } 884 } 885 } 886 887 check_template_shadow (x); 888 889 /* If this is a function conjured up by the back end, massage it 890 so it looks friendly. */ 891 if (DECL_NON_THUNK_FUNCTION_P (x) && ! DECL_LANG_SPECIFIC (x)) 892 { 893 retrofit_lang_decl (x); 894 SET_DECL_LANGUAGE (x, lang_c); 895 } 896 897 t = x; 898 if (DECL_NON_THUNK_FUNCTION_P (x) && ! DECL_FUNCTION_MEMBER_P (x)) 899 { 900 t = push_overloaded_decl (x, PUSH_LOCAL, is_friend); 901 if (!namespace_bindings_p ()) 902 /* We do not need to create a binding for this name; 903 push_overloaded_decl will have already done so if 904 necessary. */ 905 need_new_binding = 0; 906 } 907 else if (DECL_FUNCTION_TEMPLATE_P (x) && DECL_NAMESPACE_SCOPE_P (x)) 908 { 909 t = push_overloaded_decl (x, PUSH_GLOBAL, is_friend); 910 if (t == x) 911 add_decl_to_level (x, NAMESPACE_LEVEL (CP_DECL_CONTEXT (t))); 912 } 913 914 if (TREE_CODE (t) == FUNCTION_DECL || DECL_FUNCTION_TEMPLATE_P (t)) 915 check_default_args (t); 916 917 if (t != x || DECL_FUNCTION_TEMPLATE_P (t)) 918 return t; 919 920 /* If declaring a type as a typedef, copy the type (unless we're 921 at line 0), and install this TYPE_DECL as the new type's typedef 922 name. See the extensive comment of set_underlying_type (). */ 923 if (TREE_CODE (x) == TYPE_DECL) 924 { 925 tree type = TREE_TYPE (x); 926 927 if (DECL_IS_BUILTIN (x) 928 || (TREE_TYPE (x) != error_mark_node 929 && TYPE_NAME (type) != x 930 /* We don't want to copy the type when all we're 931 doing is making a TYPE_DECL for the purposes of 932 inlining. */ 933 && (!TYPE_NAME (type) 934 || TYPE_NAME (type) != DECL_ABSTRACT_ORIGIN (x)))) 935 set_underlying_type (x); 936 937 if (type != error_mark_node 938 && TYPE_NAME (type) 939 && TYPE_IDENTIFIER (type)) 940 set_identifier_type_value (DECL_NAME (x), x); 941 942 /* If this is a locally defined typedef in a function that 943 is not a template instantation, record it to implement 944 -Wunused-local-typedefs. */ 945 if (current_instantiation () == NULL 946 || (current_instantiation ()->decl != current_function_decl)) 947 record_locally_defined_typedef (x); 948 } 949 950 /* Multiple external decls of the same identifier ought to match. 951 952 We get warnings about inline functions where they are defined. 953 We get warnings about other functions from push_overloaded_decl. 954 955 Avoid duplicate warnings where they are used. */ 956 if (TREE_PUBLIC (x) && TREE_CODE (x) != FUNCTION_DECL) 957 { 958 tree decl; 959 960 decl = IDENTIFIER_NAMESPACE_VALUE (name); 961 if (decl && TREE_CODE (decl) == OVERLOAD) 962 decl = OVL_FUNCTION (decl); 963 964 if (decl && decl != error_mark_node 965 && (DECL_EXTERNAL (decl) || TREE_PUBLIC (decl)) 966 /* If different sort of thing, we already gave an error. */ 967 && TREE_CODE (decl) == TREE_CODE (x) 968 && !same_type_p (TREE_TYPE (x), TREE_TYPE (decl))) 969 { 970 permerror (input_location, "type mismatch with previous external decl of %q#D", x); 971 permerror (input_location, "previous external decl of %q+#D", decl); 972 } 973 } 974 975 if (TREE_CODE (x) == FUNCTION_DECL 976 && is_friend 977 && !flag_friend_injection) 978 { 979 /* This is a new declaration of a friend function, so hide 980 it from ordinary function lookup. */ 981 DECL_ANTICIPATED (x) = 1; 982 DECL_HIDDEN_FRIEND_P (x) = 1; 983 } 984 985 /* This name is new in its binding level. 986 Install the new declaration and return it. */ 987 if (namespace_bindings_p ()) 988 { 989 /* Install a global value. */ 990 991 /* If the first global decl has external linkage, 992 warn if we later see static one. */ 993 if (IDENTIFIER_GLOBAL_VALUE (name) == NULL_TREE && TREE_PUBLIC (x)) 994 TREE_PUBLIC (name) = 1; 995 996 /* Bind the name for the entity. */ 997 if (!(TREE_CODE (x) == TYPE_DECL && DECL_ARTIFICIAL (x) 998 && t != NULL_TREE) 999 && (TREE_CODE (x) == TYPE_DECL 1000 || TREE_CODE (x) == VAR_DECL 1001 || TREE_CODE (x) == NAMESPACE_DECL 1002 || TREE_CODE (x) == CONST_DECL 1003 || TREE_CODE (x) == TEMPLATE_DECL)) 1004 SET_IDENTIFIER_NAMESPACE_VALUE (name, x); 1005 1006 /* If new decl is `static' and an `extern' was seen previously, 1007 warn about it. */ 1008 if (x != NULL_TREE && t != NULL_TREE && decls_match (x, t)) 1009 warn_extern_redeclared_static (x, t); 1010 } 1011 else 1012 { 1013 /* Here to install a non-global value. */ 1014 tree oldglobal = IDENTIFIER_NAMESPACE_VALUE (name); 1015 tree oldlocal = NULL_TREE; 1016 cp_binding_level *oldscope = NULL; 1017 cxx_binding *oldbinding = outer_binding (name, NULL, true); 1018 if (oldbinding) 1019 { 1020 oldlocal = oldbinding->value; 1021 oldscope = oldbinding->scope; 1022 } 1023 1024 if (need_new_binding) 1025 { 1026 push_local_binding (name, x, 0); 1027 /* Because push_local_binding will hook X on to the 1028 current_binding_level's name list, we don't want to 1029 do that again below. */ 1030 need_new_binding = 0; 1031 } 1032 1033 /* If this is a TYPE_DECL, push it into the type value slot. */ 1034 if (TREE_CODE (x) == TYPE_DECL) 1035 set_identifier_type_value (name, x); 1036 1037 /* Clear out any TYPE_DECL shadowed by a namespace so that 1038 we won't think this is a type. The C struct hack doesn't 1039 go through namespaces. */ 1040 if (TREE_CODE (x) == NAMESPACE_DECL) 1041 set_identifier_type_value (name, NULL_TREE); 1042 1043 if (oldlocal) 1044 { 1045 tree d = oldlocal; 1046 1047 while (oldlocal 1048 && TREE_CODE (oldlocal) == VAR_DECL 1049 && DECL_DEAD_FOR_LOCAL (oldlocal)) 1050 oldlocal = DECL_SHADOWED_FOR_VAR (oldlocal); 1051 1052 if (oldlocal == NULL_TREE) 1053 oldlocal = IDENTIFIER_NAMESPACE_VALUE (DECL_NAME (d)); 1054 } 1055 1056 /* If this is an extern function declaration, see if we 1057 have a global definition or declaration for the function. */ 1058 if (oldlocal == NULL_TREE 1059 && DECL_EXTERNAL (x) 1060 && oldglobal != NULL_TREE 1061 && TREE_CODE (x) == FUNCTION_DECL 1062 && TREE_CODE (oldglobal) == FUNCTION_DECL) 1063 { 1064 /* We have one. Their types must agree. */ 1065 if (decls_match (x, oldglobal)) 1066 /* OK */; 1067 else 1068 { 1069 warning (0, "extern declaration of %q#D doesn%'t match", x); 1070 warning (0, "global declaration %q+#D", oldglobal); 1071 } 1072 } 1073 /* If we have a local external declaration, 1074 and no file-scope declaration has yet been seen, 1075 then if we later have a file-scope decl it must not be static. */ 1076 if (oldlocal == NULL_TREE 1077 && oldglobal == NULL_TREE 1078 && DECL_EXTERNAL (x) 1079 && TREE_PUBLIC (x)) 1080 TREE_PUBLIC (name) = 1; 1081 1082 /* Don't complain about the parms we push and then pop 1083 while tentatively parsing a function declarator. */ 1084 if (TREE_CODE (x) == PARM_DECL && DECL_CONTEXT (x) == NULL_TREE) 1085 /* Ignore. */; 1086 1087 /* Warn if shadowing an argument at the top level of the body. */ 1088 else if (oldlocal != NULL_TREE && !DECL_EXTERNAL (x) 1089 /* Inline decls shadow nothing. */ 1090 && !DECL_FROM_INLINE (x) 1091 && (TREE_CODE (oldlocal) == PARM_DECL 1092 || TREE_CODE (oldlocal) == VAR_DECL 1093 /* If the old decl is a type decl, only warn if the 1094 old decl is an explicit typedef or if both the old 1095 and new decls are type decls. */ 1096 || (TREE_CODE (oldlocal) == TYPE_DECL 1097 && (!DECL_ARTIFICIAL (oldlocal) 1098 || TREE_CODE (x) == TYPE_DECL))) 1099 /* Don't check for internally generated vars unless 1100 it's an implicit typedef (see create_implicit_typedef 1101 in decl.c). */ 1102 && (!DECL_ARTIFICIAL (x) || DECL_IMPLICIT_TYPEDEF_P (x))) 1103 { 1104 bool nowarn = false; 1105 1106 /* Don't complain if it's from an enclosing function. */ 1107 if (DECL_CONTEXT (oldlocal) == current_function_decl 1108 && TREE_CODE (x) != PARM_DECL 1109 && TREE_CODE (oldlocal) == PARM_DECL) 1110 { 1111 /* Go to where the parms should be and see if we find 1112 them there. */ 1113 cp_binding_level *b = current_binding_level->level_chain; 1114 1115 if (FUNCTION_NEEDS_BODY_BLOCK (current_function_decl)) 1116 /* Skip the ctor/dtor cleanup level. */ 1117 b = b->level_chain; 1118 1119 /* ARM $8.3 */ 1120 if (b->kind == sk_function_parms) 1121 { 1122 error ("declaration of %q#D shadows a parameter", x); 1123 nowarn = true; 1124 } 1125 } 1126 1127 /* The local structure or class can't use parameters of 1128 the containing function anyway. */ 1129 if (DECL_CONTEXT (oldlocal) != current_function_decl) 1130 { 1131 cp_binding_level *scope = current_binding_level; 1132 tree context = DECL_CONTEXT (oldlocal); 1133 for (; scope; scope = scope->level_chain) 1134 { 1135 if (scope->kind == sk_function_parms 1136 && scope->this_entity == context) 1137 break; 1138 if (scope->kind == sk_class 1139 && !LAMBDA_TYPE_P (scope->this_entity)) 1140 { 1141 nowarn = true; 1142 break; 1143 } 1144 } 1145 } 1146 /* Error if redeclaring a local declared in a 1147 for-init-statement or in the condition of an if or 1148 switch statement when the new declaration is in the 1149 outermost block of the controlled statement. 1150 Redeclaring a variable from a for or while condition is 1151 detected elsewhere. */ 1152 else if (TREE_CODE (oldlocal) == VAR_DECL 1153 && oldscope == current_binding_level->level_chain 1154 && (oldscope->kind == sk_cond 1155 || oldscope->kind == sk_for)) 1156 { 1157 error ("redeclaration of %q#D", x); 1158 error ("%q+#D previously declared here", oldlocal); 1159 } 1160 1161 if (warn_shadow && !nowarn) 1162 { 1163 if (TREE_CODE (oldlocal) == PARM_DECL) 1164 warning_at (input_location, OPT_Wshadow, 1165 "declaration of %q#D shadows a parameter", x); 1166 else if (is_capture_proxy (oldlocal)) 1167 warning_at (input_location, OPT_Wshadow, 1168 "declaration of %qD shadows a lambda capture", 1169 x); 1170 else 1171 warning_at (input_location, OPT_Wshadow, 1172 "declaration of %qD shadows a previous local", 1173 x); 1174 warning_at (DECL_SOURCE_LOCATION (oldlocal), OPT_Wshadow, 1175 "shadowed declaration is here"); 1176 } 1177 } 1178 1179 /* Maybe warn if shadowing something else. */ 1180 else if (warn_shadow && !DECL_EXTERNAL (x) 1181 /* No shadow warnings for internally generated vars unless 1182 it's an implicit typedef (see create_implicit_typedef 1183 in decl.c). */ 1184 && (! DECL_ARTIFICIAL (x) || DECL_IMPLICIT_TYPEDEF_P (x)) 1185 /* No shadow warnings for vars made for inlining. */ 1186 && ! DECL_FROM_INLINE (x)) 1187 { 1188 tree member; 1189 1190 if (current_class_ptr) 1191 member = lookup_member (current_class_type, 1192 name, 1193 /*protect=*/0, 1194 /*want_type=*/false, 1195 tf_warning_or_error); 1196 else 1197 member = NULL_TREE; 1198 1199 if (member && !TREE_STATIC (member)) 1200 { 1201 /* Location of previous decl is not useful in this case. */ 1202 warning (OPT_Wshadow, "declaration of %qD shadows a member of 'this'", 1203 x); 1204 } 1205 else if (oldglobal != NULL_TREE 1206 && (TREE_CODE (oldglobal) == VAR_DECL 1207 /* If the old decl is a type decl, only warn if the 1208 old decl is an explicit typedef or if both the 1209 old and new decls are type decls. */ 1210 || (TREE_CODE (oldglobal) == TYPE_DECL 1211 && (!DECL_ARTIFICIAL (oldglobal) 1212 || TREE_CODE (x) == TYPE_DECL)))) 1213 /* XXX shadow warnings in outer-more namespaces */ 1214 { 1215 warning_at (input_location, OPT_Wshadow, 1216 "declaration of %qD shadows a global declaration", x); 1217 warning_at (DECL_SOURCE_LOCATION (oldglobal), OPT_Wshadow, 1218 "shadowed declaration is here"); 1219 } 1220 } 1221 } 1222 1223 if (TREE_CODE (x) == VAR_DECL) 1224 maybe_register_incomplete_var (x); 1225 } 1226 1227 if (need_new_binding) 1228 add_decl_to_level (x, 1229 DECL_NAMESPACE_SCOPE_P (x) 1230 ? NAMESPACE_LEVEL (CP_DECL_CONTEXT (x)) 1231 : current_binding_level); 1232 1233 return x; 1234 } 1235 1236 /* Wrapper for pushdecl_maybe_friend_1. */ 1237 1238 tree 1239 pushdecl_maybe_friend (tree x, bool is_friend) 1240 { 1241 tree ret; 1242 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 1243 ret = pushdecl_maybe_friend_1 (x, is_friend); 1244 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 1245 return ret; 1246 } 1247 1248 /* Record a decl-node X as belonging to the current lexical scope. */ 1249 1250 tree 1251 pushdecl (tree x) 1252 { 1253 return pushdecl_maybe_friend (x, false); 1254 } 1255 1256 /* Enter DECL into the symbol table, if that's appropriate. Returns 1257 DECL, or a modified version thereof. */ 1258 1259 tree 1260 maybe_push_decl (tree decl) 1261 { 1262 tree type = TREE_TYPE (decl); 1263 1264 /* Add this decl to the current binding level, but not if it comes 1265 from another scope, e.g. a static member variable. TEM may equal 1266 DECL or it may be a previous decl of the same name. */ 1267 if (decl == error_mark_node 1268 || (TREE_CODE (decl) != PARM_DECL 1269 && DECL_CONTEXT (decl) != NULL_TREE 1270 /* Definitions of namespace members outside their namespace are 1271 possible. */ 1272 && !DECL_NAMESPACE_SCOPE_P (decl)) 1273 || (TREE_CODE (decl) == TEMPLATE_DECL && !namespace_bindings_p ()) 1274 || type == unknown_type_node 1275 /* The declaration of a template specialization does not affect 1276 the functions available for overload resolution, so we do not 1277 call pushdecl. */ 1278 || (TREE_CODE (decl) == FUNCTION_DECL 1279 && DECL_TEMPLATE_SPECIALIZATION (decl))) 1280 return decl; 1281 else 1282 return pushdecl (decl); 1283 } 1284 1285 /* Bind DECL to ID in the current_binding_level, assumed to be a local 1286 binding level. If PUSH_USING is set in FLAGS, we know that DECL 1287 doesn't really belong to this binding level, that it got here 1288 through a using-declaration. */ 1289 1290 void 1291 push_local_binding (tree id, tree decl, int flags) 1292 { 1293 cp_binding_level *b; 1294 1295 /* Skip over any local classes. This makes sense if we call 1296 push_local_binding with a friend decl of a local class. */ 1297 b = innermost_nonclass_level (); 1298 1299 if (lookup_name_innermost_nonclass_level (id)) 1300 { 1301 /* Supplement the existing binding. */ 1302 if (!supplement_binding (IDENTIFIER_BINDING (id), decl)) 1303 /* It didn't work. Something else must be bound at this 1304 level. Do not add DECL to the list of things to pop 1305 later. */ 1306 return; 1307 } 1308 else 1309 /* Create a new binding. */ 1310 push_binding (id, decl, b); 1311 1312 if (TREE_CODE (decl) == OVERLOAD || (flags & PUSH_USING)) 1313 /* We must put the OVERLOAD into a TREE_LIST since the 1314 TREE_CHAIN of an OVERLOAD is already used. Similarly for 1315 decls that got here through a using-declaration. */ 1316 decl = build_tree_list (NULL_TREE, decl); 1317 1318 /* And put DECL on the list of things declared by the current 1319 binding level. */ 1320 add_decl_to_level (decl, b); 1321 } 1322 1323 /* Check to see whether or not DECL is a variable that would have been 1324 in scope under the ARM, but is not in scope under the ANSI/ISO 1325 standard. If so, issue an error message. If name lookup would 1326 work in both cases, but return a different result, this function 1327 returns the result of ANSI/ISO lookup. Otherwise, it returns 1328 DECL. */ 1329 1330 tree 1331 check_for_out_of_scope_variable (tree decl) 1332 { 1333 tree shadowed; 1334 1335 /* We only care about out of scope variables. */ 1336 if (!(TREE_CODE (decl) == VAR_DECL && DECL_DEAD_FOR_LOCAL (decl))) 1337 return decl; 1338 1339 shadowed = DECL_HAS_SHADOWED_FOR_VAR_P (decl) 1340 ? DECL_SHADOWED_FOR_VAR (decl) : NULL_TREE ; 1341 while (shadowed != NULL_TREE && TREE_CODE (shadowed) == VAR_DECL 1342 && DECL_DEAD_FOR_LOCAL (shadowed)) 1343 shadowed = DECL_HAS_SHADOWED_FOR_VAR_P (shadowed) 1344 ? DECL_SHADOWED_FOR_VAR (shadowed) : NULL_TREE; 1345 if (!shadowed) 1346 shadowed = IDENTIFIER_NAMESPACE_VALUE (DECL_NAME (decl)); 1347 if (shadowed) 1348 { 1349 if (!DECL_ERROR_REPORTED (decl)) 1350 { 1351 warning (0, "name lookup of %qD changed", DECL_NAME (decl)); 1352 warning (0, " matches this %q+D under ISO standard rules", 1353 shadowed); 1354 warning (0, " matches this %q+D under old rules", decl); 1355 DECL_ERROR_REPORTED (decl) = 1; 1356 } 1357 return shadowed; 1358 } 1359 1360 /* If we have already complained about this declaration, there's no 1361 need to do it again. */ 1362 if (DECL_ERROR_REPORTED (decl)) 1363 return decl; 1364 1365 DECL_ERROR_REPORTED (decl) = 1; 1366 1367 if (TREE_TYPE (decl) == error_mark_node) 1368 return decl; 1369 1370 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (decl))) 1371 { 1372 error ("name lookup of %qD changed for ISO %<for%> scoping", 1373 DECL_NAME (decl)); 1374 error (" cannot use obsolete binding at %q+D because " 1375 "it has a destructor", decl); 1376 return error_mark_node; 1377 } 1378 else 1379 { 1380 permerror (input_location, "name lookup of %qD changed for ISO %<for%> scoping", 1381 DECL_NAME (decl)); 1382 if (flag_permissive) 1383 permerror (input_location, " using obsolete binding at %q+D", decl); 1384 else 1385 { 1386 static bool hint; 1387 if (!hint) 1388 { 1389 inform (input_location, "(if you use %<-fpermissive%> G++ will accept your code)"); 1390 hint = true; 1391 } 1392 } 1393 } 1394 1395 return decl; 1396 } 1397 1398 /* true means unconditionally make a BLOCK for the next level pushed. */ 1399 1400 static bool keep_next_level_flag; 1401 1402 static int binding_depth = 0; 1403 1404 static void 1405 indent (int depth) 1406 { 1407 int i; 1408 1409 for (i = 0; i < depth * 2; i++) 1410 putc (' ', stderr); 1411 } 1412 1413 /* Return a string describing the kind of SCOPE we have. */ 1414 static const char * 1415 cp_binding_level_descriptor (cp_binding_level *scope) 1416 { 1417 /* The order of this table must match the "scope_kind" 1418 enumerators. */ 1419 static const char* scope_kind_names[] = { 1420 "block-scope", 1421 "cleanup-scope", 1422 "try-scope", 1423 "catch-scope", 1424 "for-scope", 1425 "function-parameter-scope", 1426 "class-scope", 1427 "namespace-scope", 1428 "template-parameter-scope", 1429 "template-explicit-spec-scope" 1430 }; 1431 const scope_kind kind = scope->explicit_spec_p 1432 ? sk_template_spec : scope->kind; 1433 1434 return scope_kind_names[kind]; 1435 } 1436 1437 /* Output a debugging information about SCOPE when performing 1438 ACTION at LINE. */ 1439 static void 1440 cp_binding_level_debug (cp_binding_level *scope, int line, const char *action) 1441 { 1442 const char *desc = cp_binding_level_descriptor (scope); 1443 if (scope->this_entity) 1444 verbatim ("%s %s(%E) %p %d\n", action, desc, 1445 scope->this_entity, (void *) scope, line); 1446 else 1447 verbatim ("%s %s %p %d\n", action, desc, (void *) scope, line); 1448 } 1449 1450 /* Return the estimated initial size of the hashtable of a NAMESPACE 1451 scope. */ 1452 1453 static inline size_t 1454 namespace_scope_ht_size (tree ns) 1455 { 1456 tree name = DECL_NAME (ns); 1457 1458 return name == std_identifier 1459 ? NAMESPACE_STD_HT_SIZE 1460 : (name == global_scope_name 1461 ? GLOBAL_SCOPE_HT_SIZE 1462 : NAMESPACE_ORDINARY_HT_SIZE); 1463 } 1464 1465 /* A chain of binding_level structures awaiting reuse. */ 1466 1467 static GTY((deletable)) cp_binding_level *free_binding_level; 1468 1469 /* Insert SCOPE as the innermost binding level. */ 1470 1471 void 1472 push_binding_level (cp_binding_level *scope) 1473 { 1474 /* Add it to the front of currently active scopes stack. */ 1475 scope->level_chain = current_binding_level; 1476 current_binding_level = scope; 1477 keep_next_level_flag = false; 1478 1479 if (ENABLE_SCOPE_CHECKING) 1480 { 1481 scope->binding_depth = binding_depth; 1482 indent (binding_depth); 1483 cp_binding_level_debug (scope, input_line, "push"); 1484 binding_depth++; 1485 } 1486 } 1487 1488 /* Create a new KIND scope and make it the top of the active scopes stack. 1489 ENTITY is the scope of the associated C++ entity (namespace, class, 1490 function, C++0x enumeration); it is NULL otherwise. */ 1491 1492 cp_binding_level * 1493 begin_scope (scope_kind kind, tree entity) 1494 { 1495 cp_binding_level *scope; 1496 1497 /* Reuse or create a struct for this binding level. */ 1498 if (!ENABLE_SCOPE_CHECKING && free_binding_level) 1499 { 1500 scope = free_binding_level; 1501 memset (scope, 0, sizeof (cp_binding_level)); 1502 free_binding_level = scope->level_chain; 1503 } 1504 else 1505 scope = ggc_alloc_cleared_cp_binding_level (); 1506 1507 scope->this_entity = entity; 1508 scope->more_cleanups_ok = true; 1509 switch (kind) 1510 { 1511 case sk_cleanup: 1512 scope->keep = true; 1513 break; 1514 1515 case sk_template_spec: 1516 scope->explicit_spec_p = true; 1517 kind = sk_template_parms; 1518 /* Fall through. */ 1519 case sk_template_parms: 1520 case sk_block: 1521 case sk_try: 1522 case sk_catch: 1523 case sk_for: 1524 case sk_cond: 1525 case sk_class: 1526 case sk_scoped_enum: 1527 case sk_function_parms: 1528 case sk_omp: 1529 scope->keep = keep_next_level_flag; 1530 break; 1531 1532 case sk_namespace: 1533 NAMESPACE_LEVEL (entity) = scope; 1534 scope->static_decls = 1535 VEC_alloc (tree, gc, 1536 DECL_NAME (entity) == std_identifier 1537 || DECL_NAME (entity) == global_scope_name 1538 ? 200 : 10); 1539 break; 1540 1541 default: 1542 /* Should not happen. */ 1543 gcc_unreachable (); 1544 break; 1545 } 1546 scope->kind = kind; 1547 1548 push_binding_level (scope); 1549 1550 return scope; 1551 } 1552 1553 /* We're about to leave current scope. Pop the top of the stack of 1554 currently active scopes. Return the enclosing scope, now active. */ 1555 1556 cp_binding_level * 1557 leave_scope (void) 1558 { 1559 cp_binding_level *scope = current_binding_level; 1560 1561 if (scope->kind == sk_namespace && class_binding_level) 1562 current_binding_level = class_binding_level; 1563 1564 /* We cannot leave a scope, if there are none left. */ 1565 if (NAMESPACE_LEVEL (global_namespace)) 1566 gcc_assert (!global_scope_p (scope)); 1567 1568 if (ENABLE_SCOPE_CHECKING) 1569 { 1570 indent (--binding_depth); 1571 cp_binding_level_debug (scope, input_line, "leave"); 1572 } 1573 1574 /* Move one nesting level up. */ 1575 current_binding_level = scope->level_chain; 1576 1577 /* Namespace-scopes are left most probably temporarily, not 1578 completely; they can be reopened later, e.g. in namespace-extension 1579 or any name binding activity that requires us to resume a 1580 namespace. For classes, we cache some binding levels. For other 1581 scopes, we just make the structure available for reuse. */ 1582 if (scope->kind != sk_namespace 1583 && scope->kind != sk_class) 1584 { 1585 scope->level_chain = free_binding_level; 1586 gcc_assert (!ENABLE_SCOPE_CHECKING 1587 || scope->binding_depth == binding_depth); 1588 free_binding_level = scope; 1589 } 1590 1591 /* Find the innermost enclosing class scope, and reset 1592 CLASS_BINDING_LEVEL appropriately. */ 1593 if (scope->kind == sk_class) 1594 { 1595 class_binding_level = NULL; 1596 for (scope = current_binding_level; scope; scope = scope->level_chain) 1597 if (scope->kind == sk_class) 1598 { 1599 class_binding_level = scope; 1600 break; 1601 } 1602 } 1603 1604 return current_binding_level; 1605 } 1606 1607 static void 1608 resume_scope (cp_binding_level* b) 1609 { 1610 /* Resuming binding levels is meant only for namespaces, 1611 and those cannot nest into classes. */ 1612 gcc_assert (!class_binding_level); 1613 /* Also, resuming a non-directly nested namespace is a no-no. */ 1614 gcc_assert (b->level_chain == current_binding_level); 1615 current_binding_level = b; 1616 if (ENABLE_SCOPE_CHECKING) 1617 { 1618 b->binding_depth = binding_depth; 1619 indent (binding_depth); 1620 cp_binding_level_debug (b, input_line, "resume"); 1621 binding_depth++; 1622 } 1623 } 1624 1625 /* Return the innermost binding level that is not for a class scope. */ 1626 1627 static cp_binding_level * 1628 innermost_nonclass_level (void) 1629 { 1630 cp_binding_level *b; 1631 1632 b = current_binding_level; 1633 while (b->kind == sk_class) 1634 b = b->level_chain; 1635 1636 return b; 1637 } 1638 1639 /* We're defining an object of type TYPE. If it needs a cleanup, but 1640 we're not allowed to add any more objects with cleanups to the current 1641 scope, create a new binding level. */ 1642 1643 void 1644 maybe_push_cleanup_level (tree type) 1645 { 1646 if (type != error_mark_node 1647 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type) 1648 && current_binding_level->more_cleanups_ok == 0) 1649 { 1650 begin_scope (sk_cleanup, NULL); 1651 current_binding_level->statement_list = push_stmt_list (); 1652 } 1653 } 1654 1655 /* Return true if we are in the global binding level. */ 1656 1657 bool 1658 global_bindings_p (void) 1659 { 1660 return global_scope_p (current_binding_level); 1661 } 1662 1663 /* True if we are currently in a toplevel binding level. This 1664 means either the global binding level or a namespace in a toplevel 1665 binding level. Since there are no non-toplevel namespace levels, 1666 this really means any namespace or template parameter level. We 1667 also include a class whose context is toplevel. */ 1668 1669 bool 1670 toplevel_bindings_p (void) 1671 { 1672 cp_binding_level *b = innermost_nonclass_level (); 1673 1674 return b->kind == sk_namespace || b->kind == sk_template_parms; 1675 } 1676 1677 /* True if this is a namespace scope, or if we are defining a class 1678 which is itself at namespace scope, or whose enclosing class is 1679 such a class, etc. */ 1680 1681 bool 1682 namespace_bindings_p (void) 1683 { 1684 cp_binding_level *b = innermost_nonclass_level (); 1685 1686 return b->kind == sk_namespace; 1687 } 1688 1689 /* True if the innermost non-class scope is a block scope. */ 1690 1691 bool 1692 local_bindings_p (void) 1693 { 1694 cp_binding_level *b = innermost_nonclass_level (); 1695 return b->kind < sk_function_parms || b->kind == sk_omp; 1696 } 1697 1698 /* True if the current level needs to have a BLOCK made. */ 1699 1700 bool 1701 kept_level_p (void) 1702 { 1703 return (current_binding_level->blocks != NULL_TREE 1704 || current_binding_level->keep 1705 || current_binding_level->kind == sk_cleanup 1706 || current_binding_level->names != NULL_TREE 1707 || current_binding_level->using_directives); 1708 } 1709 1710 /* Returns the kind of the innermost scope. */ 1711 1712 scope_kind 1713 innermost_scope_kind (void) 1714 { 1715 return current_binding_level->kind; 1716 } 1717 1718 /* Returns true if this scope was created to store template parameters. */ 1719 1720 bool 1721 template_parm_scope_p (void) 1722 { 1723 return innermost_scope_kind () == sk_template_parms; 1724 } 1725 1726 /* If KEEP is true, make a BLOCK node for the next binding level, 1727 unconditionally. Otherwise, use the normal logic to decide whether 1728 or not to create a BLOCK. */ 1729 1730 void 1731 keep_next_level (bool keep) 1732 { 1733 keep_next_level_flag = keep; 1734 } 1735 1736 /* Return the list of declarations of the current level. 1737 Note that this list is in reverse order unless/until 1738 you nreverse it; and when you do nreverse it, you must 1739 store the result back using `storedecls' or you will lose. */ 1740 1741 tree 1742 getdecls (void) 1743 { 1744 return current_binding_level->names; 1745 } 1746 1747 /* Return how many function prototypes we are currently nested inside. */ 1748 1749 int 1750 function_parm_depth (void) 1751 { 1752 int level = 0; 1753 cp_binding_level *b; 1754 1755 for (b = current_binding_level; 1756 b->kind == sk_function_parms; 1757 b = b->level_chain) 1758 ++level; 1759 1760 return level; 1761 } 1762 1763 /* For debugging. */ 1764 static int no_print_functions = 0; 1765 static int no_print_builtins = 0; 1766 1767 static void 1768 print_binding_level (cp_binding_level* lvl) 1769 { 1770 tree t; 1771 int i = 0, len; 1772 fprintf (stderr, " blocks=%p", (void *) lvl->blocks); 1773 if (lvl->more_cleanups_ok) 1774 fprintf (stderr, " more-cleanups-ok"); 1775 if (lvl->have_cleanups) 1776 fprintf (stderr, " have-cleanups"); 1777 fprintf (stderr, "\n"); 1778 if (lvl->names) 1779 { 1780 fprintf (stderr, " names:\t"); 1781 /* We can probably fit 3 names to a line? */ 1782 for (t = lvl->names; t; t = TREE_CHAIN (t)) 1783 { 1784 if (no_print_functions && (TREE_CODE (t) == FUNCTION_DECL)) 1785 continue; 1786 if (no_print_builtins 1787 && (TREE_CODE (t) == TYPE_DECL) 1788 && DECL_IS_BUILTIN (t)) 1789 continue; 1790 1791 /* Function decls tend to have longer names. */ 1792 if (TREE_CODE (t) == FUNCTION_DECL) 1793 len = 3; 1794 else 1795 len = 2; 1796 i += len; 1797 if (i > 6) 1798 { 1799 fprintf (stderr, "\n\t"); 1800 i = len; 1801 } 1802 print_node_brief (stderr, "", t, 0); 1803 if (t == error_mark_node) 1804 break; 1805 } 1806 if (i) 1807 fprintf (stderr, "\n"); 1808 } 1809 if (VEC_length (cp_class_binding, lvl->class_shadowed)) 1810 { 1811 size_t i; 1812 cp_class_binding *b; 1813 fprintf (stderr, " class-shadowed:"); 1814 FOR_EACH_VEC_ELT (cp_class_binding, lvl->class_shadowed, i, b) 1815 fprintf (stderr, " %s ", IDENTIFIER_POINTER (b->identifier)); 1816 fprintf (stderr, "\n"); 1817 } 1818 if (lvl->type_shadowed) 1819 { 1820 fprintf (stderr, " type-shadowed:"); 1821 for (t = lvl->type_shadowed; t; t = TREE_CHAIN (t)) 1822 { 1823 fprintf (stderr, " %s ", IDENTIFIER_POINTER (TREE_PURPOSE (t))); 1824 } 1825 fprintf (stderr, "\n"); 1826 } 1827 } 1828 1829 void 1830 print_other_binding_stack (cp_binding_level *stack) 1831 { 1832 cp_binding_level *level; 1833 for (level = stack; !global_scope_p (level); level = level->level_chain) 1834 { 1835 fprintf (stderr, "binding level %p\n", (void *) level); 1836 print_binding_level (level); 1837 } 1838 } 1839 1840 void 1841 print_binding_stack (void) 1842 { 1843 cp_binding_level *b; 1844 fprintf (stderr, "current_binding_level=%p\n" 1845 "class_binding_level=%p\n" 1846 "NAMESPACE_LEVEL (global_namespace)=%p\n", 1847 (void *) current_binding_level, (void *) class_binding_level, 1848 (void *) NAMESPACE_LEVEL (global_namespace)); 1849 if (class_binding_level) 1850 { 1851 for (b = class_binding_level; b; b = b->level_chain) 1852 if (b == current_binding_level) 1853 break; 1854 if (b) 1855 b = class_binding_level; 1856 else 1857 b = current_binding_level; 1858 } 1859 else 1860 b = current_binding_level; 1861 print_other_binding_stack (b); 1862 fprintf (stderr, "global:\n"); 1863 print_binding_level (NAMESPACE_LEVEL (global_namespace)); 1864 } 1865 1866 /* Return the type associated with ID. */ 1867 1868 static tree 1869 identifier_type_value_1 (tree id) 1870 { 1871 /* There is no type with that name, anywhere. */ 1872 if (REAL_IDENTIFIER_TYPE_VALUE (id) == NULL_TREE) 1873 return NULL_TREE; 1874 /* This is not the type marker, but the real thing. */ 1875 if (REAL_IDENTIFIER_TYPE_VALUE (id) != global_type_node) 1876 return REAL_IDENTIFIER_TYPE_VALUE (id); 1877 /* Have to search for it. It must be on the global level, now. 1878 Ask lookup_name not to return non-types. */ 1879 id = lookup_name_real (id, 2, 1, /*block_p=*/true, 0, LOOKUP_COMPLAIN); 1880 if (id) 1881 return TREE_TYPE (id); 1882 return NULL_TREE; 1883 } 1884 1885 /* Wrapper for identifier_type_value_1. */ 1886 1887 tree 1888 identifier_type_value (tree id) 1889 { 1890 tree ret; 1891 timevar_start (TV_NAME_LOOKUP); 1892 ret = identifier_type_value_1 (id); 1893 timevar_stop (TV_NAME_LOOKUP); 1894 return ret; 1895 } 1896 1897 1898 /* Return the IDENTIFIER_GLOBAL_VALUE of T, for use in common code, since 1899 the definition of IDENTIFIER_GLOBAL_VALUE is different for C and C++. */ 1900 1901 tree 1902 identifier_global_value (tree t) 1903 { 1904 return IDENTIFIER_GLOBAL_VALUE (t); 1905 } 1906 1907 /* Push a definition of struct, union or enum tag named ID. into 1908 binding_level B. DECL is a TYPE_DECL for the type. We assume that 1909 the tag ID is not already defined. */ 1910 1911 static void 1912 set_identifier_type_value_with_scope (tree id, tree decl, cp_binding_level *b) 1913 { 1914 tree type; 1915 1916 if (b->kind != sk_namespace) 1917 { 1918 /* Shadow the marker, not the real thing, so that the marker 1919 gets restored later. */ 1920 tree old_type_value = REAL_IDENTIFIER_TYPE_VALUE (id); 1921 b->type_shadowed 1922 = tree_cons (id, old_type_value, b->type_shadowed); 1923 type = decl ? TREE_TYPE (decl) : NULL_TREE; 1924 TREE_TYPE (b->type_shadowed) = type; 1925 } 1926 else 1927 { 1928 cxx_binding *binding = 1929 binding_for_name (NAMESPACE_LEVEL (current_namespace), id); 1930 gcc_assert (decl); 1931 if (binding->value) 1932 supplement_binding (binding, decl); 1933 else 1934 binding->value = decl; 1935 1936 /* Store marker instead of real type. */ 1937 type = global_type_node; 1938 } 1939 SET_IDENTIFIER_TYPE_VALUE (id, type); 1940 } 1941 1942 /* As set_identifier_type_value_with_scope, but using 1943 current_binding_level. */ 1944 1945 void 1946 set_identifier_type_value (tree id, tree decl) 1947 { 1948 set_identifier_type_value_with_scope (id, decl, current_binding_level); 1949 } 1950 1951 /* Return the name for the constructor (or destructor) for the 1952 specified class TYPE. When given a template, this routine doesn't 1953 lose the specialization. */ 1954 1955 static inline tree 1956 constructor_name_full (tree type) 1957 { 1958 return TYPE_IDENTIFIER (TYPE_MAIN_VARIANT (type)); 1959 } 1960 1961 /* Return the name for the constructor (or destructor) for the 1962 specified class. When given a template, return the plain 1963 unspecialized name. */ 1964 1965 tree 1966 constructor_name (tree type) 1967 { 1968 tree name; 1969 name = constructor_name_full (type); 1970 if (IDENTIFIER_TEMPLATE (name)) 1971 name = IDENTIFIER_TEMPLATE (name); 1972 return name; 1973 } 1974 1975 /* Returns TRUE if NAME is the name for the constructor for TYPE, 1976 which must be a class type. */ 1977 1978 bool 1979 constructor_name_p (tree name, tree type) 1980 { 1981 tree ctor_name; 1982 1983 gcc_assert (MAYBE_CLASS_TYPE_P (type)); 1984 1985 if (!name) 1986 return false; 1987 1988 if (TREE_CODE (name) != IDENTIFIER_NODE) 1989 return false; 1990 1991 /* These don't have names. */ 1992 if (TREE_CODE (type) == DECLTYPE_TYPE 1993 || TREE_CODE (type) == TYPEOF_TYPE) 1994 return false; 1995 1996 ctor_name = constructor_name_full (type); 1997 if (name == ctor_name) 1998 return true; 1999 if (IDENTIFIER_TEMPLATE (ctor_name) 2000 && name == IDENTIFIER_TEMPLATE (ctor_name)) 2001 return true; 2002 return false; 2003 } 2004 2005 /* Counter used to create anonymous type names. */ 2006 2007 static GTY(()) int anon_cnt; 2008 2009 /* Return an IDENTIFIER which can be used as a name for 2010 anonymous structs and unions. */ 2011 2012 tree 2013 make_anon_name (void) 2014 { 2015 char buf[32]; 2016 2017 sprintf (buf, ANON_AGGRNAME_FORMAT, anon_cnt++); 2018 return get_identifier (buf); 2019 } 2020 2021 /* This code is practically identical to that for creating 2022 anonymous names, but is just used for lambdas instead. This is necessary 2023 because anonymous names are recognized and cannot be passed to template 2024 functions. */ 2025 /* FIXME is this still necessary? */ 2026 2027 static GTY(()) int lambda_cnt = 0; 2028 2029 tree 2030 make_lambda_name (void) 2031 { 2032 char buf[32]; 2033 2034 sprintf (buf, LAMBDANAME_FORMAT, lambda_cnt++); 2035 return get_identifier (buf); 2036 } 2037 2038 /* Return (from the stack of) the BINDING, if any, established at SCOPE. */ 2039 2040 static inline cxx_binding * 2041 find_binding (cp_binding_level *scope, cxx_binding *binding) 2042 { 2043 for (; binding != NULL; binding = binding->previous) 2044 if (binding->scope == scope) 2045 return binding; 2046 2047 return (cxx_binding *)0; 2048 } 2049 2050 /* Return the binding for NAME in SCOPE, if any. Otherwise, return NULL. */ 2051 2052 static inline cxx_binding * 2053 cp_binding_level_find_binding_for_name (cp_binding_level *scope, tree name) 2054 { 2055 cxx_binding *b = IDENTIFIER_NAMESPACE_BINDINGS (name); 2056 if (b) 2057 { 2058 /* Fold-in case where NAME is used only once. */ 2059 if (scope == b->scope && b->previous == NULL) 2060 return b; 2061 return find_binding (scope, b); 2062 } 2063 return NULL; 2064 } 2065 2066 /* Always returns a binding for name in scope. If no binding is 2067 found, make a new one. */ 2068 2069 static cxx_binding * 2070 binding_for_name (cp_binding_level *scope, tree name) 2071 { 2072 cxx_binding *result; 2073 2074 result = cp_binding_level_find_binding_for_name (scope, name); 2075 if (result) 2076 return result; 2077 /* Not found, make a new one. */ 2078 result = cxx_binding_make (NULL, NULL); 2079 result->previous = IDENTIFIER_NAMESPACE_BINDINGS (name); 2080 result->scope = scope; 2081 result->is_local = false; 2082 result->value_is_inherited = false; 2083 IDENTIFIER_NAMESPACE_BINDINGS (name) = result; 2084 return result; 2085 } 2086 2087 /* Walk through the bindings associated to the name of FUNCTION, 2088 and return the first declaration of a function with a 2089 "C" linkage specification, a.k.a 'extern "C"'. 2090 This function looks for the binding, regardless of which scope it 2091 has been defined in. It basically looks in all the known scopes. 2092 Note that this function does not lookup for bindings of builtin functions 2093 or for functions declared in system headers. */ 2094 static tree 2095 lookup_extern_c_fun_in_all_ns (tree function) 2096 { 2097 tree name; 2098 cxx_binding *iter; 2099 2100 gcc_assert (function && TREE_CODE (function) == FUNCTION_DECL); 2101 2102 name = DECL_NAME (function); 2103 gcc_assert (name && TREE_CODE (name) == IDENTIFIER_NODE); 2104 2105 for (iter = IDENTIFIER_NAMESPACE_BINDINGS (name); 2106 iter; 2107 iter = iter->previous) 2108 { 2109 tree ovl; 2110 for (ovl = iter->value; ovl; ovl = OVL_NEXT (ovl)) 2111 { 2112 tree decl = OVL_CURRENT (ovl); 2113 if (decl 2114 && TREE_CODE (decl) == FUNCTION_DECL 2115 && DECL_EXTERN_C_P (decl) 2116 && !DECL_ARTIFICIAL (decl)) 2117 { 2118 return decl; 2119 } 2120 } 2121 } 2122 return NULL; 2123 } 2124 2125 /* Returns a list of C-linkage decls with the name NAME. */ 2126 2127 tree 2128 c_linkage_bindings (tree name) 2129 { 2130 tree decls = NULL_TREE; 2131 cxx_binding *iter; 2132 2133 for (iter = IDENTIFIER_NAMESPACE_BINDINGS (name); 2134 iter; 2135 iter = iter->previous) 2136 { 2137 tree ovl; 2138 for (ovl = iter->value; ovl; ovl = OVL_NEXT (ovl)) 2139 { 2140 tree decl = OVL_CURRENT (ovl); 2141 if (decl 2142 && DECL_EXTERN_C_P (decl) 2143 && !DECL_ARTIFICIAL (decl)) 2144 { 2145 if (decls == NULL_TREE) 2146 decls = decl; 2147 else 2148 decls = tree_cons (NULL_TREE, decl, decls); 2149 } 2150 } 2151 } 2152 return decls; 2153 } 2154 2155 /* Insert another USING_DECL into the current binding level, returning 2156 this declaration. If this is a redeclaration, do nothing, and 2157 return NULL_TREE if this not in namespace scope (in namespace 2158 scope, a using decl might extend any previous bindings). */ 2159 2160 static tree 2161 push_using_decl_1 (tree scope, tree name) 2162 { 2163 tree decl; 2164 2165 gcc_assert (TREE_CODE (scope) == NAMESPACE_DECL); 2166 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE); 2167 for (decl = current_binding_level->usings; decl; decl = DECL_CHAIN (decl)) 2168 if (USING_DECL_SCOPE (decl) == scope && DECL_NAME (decl) == name) 2169 break; 2170 if (decl) 2171 return namespace_bindings_p () ? decl : NULL_TREE; 2172 decl = build_lang_decl (USING_DECL, name, NULL_TREE); 2173 USING_DECL_SCOPE (decl) = scope; 2174 DECL_CHAIN (decl) = current_binding_level->usings; 2175 current_binding_level->usings = decl; 2176 return decl; 2177 } 2178 2179 /* Wrapper for push_using_decl_1. */ 2180 2181 static tree 2182 push_using_decl (tree scope, tree name) 2183 { 2184 tree ret; 2185 timevar_start (TV_NAME_LOOKUP); 2186 ret = push_using_decl_1 (scope, name); 2187 timevar_stop (TV_NAME_LOOKUP); 2188 return ret; 2189 } 2190 2191 /* Same as pushdecl, but define X in binding-level LEVEL. We rely on the 2192 caller to set DECL_CONTEXT properly. 2193 2194 Note that this must only be used when X will be the new innermost 2195 binding for its name, as we tack it onto the front of IDENTIFIER_BINDING 2196 without checking to see if the current IDENTIFIER_BINDING comes from a 2197 closer binding level than LEVEL. */ 2198 2199 static tree 2200 pushdecl_with_scope_1 (tree x, cp_binding_level *level, bool is_friend) 2201 { 2202 cp_binding_level *b; 2203 tree function_decl = current_function_decl; 2204 2205 current_function_decl = NULL_TREE; 2206 if (level->kind == sk_class) 2207 { 2208 b = class_binding_level; 2209 class_binding_level = level; 2210 pushdecl_class_level (x); 2211 class_binding_level = b; 2212 } 2213 else 2214 { 2215 b = current_binding_level; 2216 current_binding_level = level; 2217 x = pushdecl_maybe_friend (x, is_friend); 2218 current_binding_level = b; 2219 } 2220 current_function_decl = function_decl; 2221 return x; 2222 } 2223 2224 /* Wrapper for pushdecl_with_scope_1. */ 2225 2226 tree 2227 pushdecl_with_scope (tree x, cp_binding_level *level, bool is_friend) 2228 { 2229 tree ret; 2230 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 2231 ret = pushdecl_with_scope_1 (x, level, is_friend); 2232 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 2233 return ret; 2234 } 2235 2236 2237 /* DECL is a FUNCTION_DECL for a non-member function, which may have 2238 other definitions already in place. We get around this by making 2239 the value of the identifier point to a list of all the things that 2240 want to be referenced by that name. It is then up to the users of 2241 that name to decide what to do with that list. 2242 2243 DECL may also be a TEMPLATE_DECL, with a FUNCTION_DECL in its 2244 DECL_TEMPLATE_RESULT. It is dealt with the same way. 2245 2246 FLAGS is a bitwise-or of the following values: 2247 PUSH_LOCAL: Bind DECL in the current scope, rather than at 2248 namespace scope. 2249 PUSH_USING: DECL is being pushed as the result of a using 2250 declaration. 2251 2252 IS_FRIEND is true if this is a friend declaration. 2253 2254 The value returned may be a previous declaration if we guessed wrong 2255 about what language DECL should belong to (C or C++). Otherwise, 2256 it's always DECL (and never something that's not a _DECL). */ 2257 2258 static tree 2259 push_overloaded_decl_1 (tree decl, int flags, bool is_friend) 2260 { 2261 tree name = DECL_NAME (decl); 2262 tree old; 2263 tree new_binding; 2264 int doing_global = (namespace_bindings_p () || !(flags & PUSH_LOCAL)); 2265 2266 if (doing_global) 2267 old = namespace_binding (name, DECL_CONTEXT (decl)); 2268 else 2269 old = lookup_name_innermost_nonclass_level (name); 2270 2271 if (old) 2272 { 2273 if (TREE_CODE (old) == TYPE_DECL && DECL_ARTIFICIAL (old)) 2274 { 2275 tree t = TREE_TYPE (old); 2276 if (MAYBE_CLASS_TYPE_P (t) && warn_shadow 2277 && (! DECL_IN_SYSTEM_HEADER (decl) 2278 || ! DECL_IN_SYSTEM_HEADER (old))) 2279 warning (OPT_Wshadow, "%q#D hides constructor for %q#T", decl, t); 2280 old = NULL_TREE; 2281 } 2282 else if (is_overloaded_fn (old)) 2283 { 2284 tree tmp; 2285 2286 for (tmp = old; tmp; tmp = OVL_NEXT (tmp)) 2287 { 2288 tree fn = OVL_CURRENT (tmp); 2289 tree dup; 2290 2291 if (TREE_CODE (tmp) == OVERLOAD && OVL_USED (tmp) 2292 && !(flags & PUSH_USING) 2293 && compparms (TYPE_ARG_TYPES (TREE_TYPE (fn)), 2294 TYPE_ARG_TYPES (TREE_TYPE (decl))) 2295 && ! decls_match (fn, decl)) 2296 error ("%q#D conflicts with previous using declaration %q#D", 2297 decl, fn); 2298 2299 dup = duplicate_decls (decl, fn, is_friend); 2300 /* If DECL was a redeclaration of FN -- even an invalid 2301 one -- pass that information along to our caller. */ 2302 if (dup == fn || dup == error_mark_node) 2303 return dup; 2304 } 2305 2306 /* We don't overload implicit built-ins. duplicate_decls() 2307 may fail to merge the decls if the new decl is e.g. a 2308 template function. */ 2309 if (TREE_CODE (old) == FUNCTION_DECL 2310 && DECL_ANTICIPATED (old) 2311 && !DECL_HIDDEN_FRIEND_P (old)) 2312 old = NULL; 2313 } 2314 else if (old == error_mark_node) 2315 /* Ignore the undefined symbol marker. */ 2316 old = NULL_TREE; 2317 else 2318 { 2319 error ("previous non-function declaration %q+#D", old); 2320 error ("conflicts with function declaration %q#D", decl); 2321 return decl; 2322 } 2323 } 2324 2325 if (old || TREE_CODE (decl) == TEMPLATE_DECL 2326 /* If it's a using declaration, we always need to build an OVERLOAD, 2327 because it's the only way to remember that the declaration comes 2328 from 'using', and have the lookup behave correctly. */ 2329 || (flags & PUSH_USING)) 2330 { 2331 if (old && TREE_CODE (old) != OVERLOAD) 2332 new_binding = ovl_cons (decl, ovl_cons (old, NULL_TREE)); 2333 else 2334 new_binding = ovl_cons (decl, old); 2335 if (flags & PUSH_USING) 2336 OVL_USED (new_binding) = 1; 2337 } 2338 else 2339 /* NAME is not ambiguous. */ 2340 new_binding = decl; 2341 2342 if (doing_global) 2343 set_namespace_binding (name, current_namespace, new_binding); 2344 else 2345 { 2346 /* We only create an OVERLOAD if there was a previous binding at 2347 this level, or if decl is a template. In the former case, we 2348 need to remove the old binding and replace it with the new 2349 binding. We must also run through the NAMES on the binding 2350 level where the name was bound to update the chain. */ 2351 2352 if (TREE_CODE (new_binding) == OVERLOAD && old) 2353 { 2354 tree *d; 2355 2356 for (d = &IDENTIFIER_BINDING (name)->scope->names; 2357 *d; 2358 d = &TREE_CHAIN (*d)) 2359 if (*d == old 2360 || (TREE_CODE (*d) == TREE_LIST 2361 && TREE_VALUE (*d) == old)) 2362 { 2363 if (TREE_CODE (*d) == TREE_LIST) 2364 /* Just replace the old binding with the new. */ 2365 TREE_VALUE (*d) = new_binding; 2366 else 2367 /* Build a TREE_LIST to wrap the OVERLOAD. */ 2368 *d = tree_cons (NULL_TREE, new_binding, 2369 TREE_CHAIN (*d)); 2370 2371 /* And update the cxx_binding node. */ 2372 IDENTIFIER_BINDING (name)->value = new_binding; 2373 return decl; 2374 } 2375 2376 /* We should always find a previous binding in this case. */ 2377 gcc_unreachable (); 2378 } 2379 2380 /* Install the new binding. */ 2381 push_local_binding (name, new_binding, flags); 2382 } 2383 2384 return decl; 2385 } 2386 2387 /* Wrapper for push_overloaded_decl_1. */ 2388 2389 static tree 2390 push_overloaded_decl (tree decl, int flags, bool is_friend) 2391 { 2392 tree ret; 2393 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 2394 ret = push_overloaded_decl_1 (decl, flags, is_friend); 2395 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 2396 return ret; 2397 } 2398 2399 /* Check a non-member using-declaration. Return the name and scope 2400 being used, and the USING_DECL, or NULL_TREE on failure. */ 2401 2402 static tree 2403 validate_nonmember_using_decl (tree decl, tree scope, tree name) 2404 { 2405 /* [namespace.udecl] 2406 A using-declaration for a class member shall be a 2407 member-declaration. */ 2408 if (TYPE_P (scope)) 2409 { 2410 error ("%qT is not a namespace", scope); 2411 return NULL_TREE; 2412 } 2413 else if (scope == error_mark_node) 2414 return NULL_TREE; 2415 2416 if (TREE_CODE (decl) == TEMPLATE_ID_EXPR) 2417 { 2418 /* 7.3.3/5 2419 A using-declaration shall not name a template-id. */ 2420 error ("a using-declaration cannot specify a template-id. " 2421 "Try %<using %D%>", name); 2422 return NULL_TREE; 2423 } 2424 2425 if (TREE_CODE (decl) == NAMESPACE_DECL) 2426 { 2427 error ("namespace %qD not allowed in using-declaration", decl); 2428 return NULL_TREE; 2429 } 2430 2431 if (TREE_CODE (decl) == SCOPE_REF) 2432 { 2433 /* It's a nested name with template parameter dependent scope. 2434 This can only be using-declaration for class member. */ 2435 error ("%qT is not a namespace", TREE_OPERAND (decl, 0)); 2436 return NULL_TREE; 2437 } 2438 2439 if (is_overloaded_fn (decl)) 2440 decl = get_first_fn (decl); 2441 2442 gcc_assert (DECL_P (decl)); 2443 2444 /* Make a USING_DECL. */ 2445 return push_using_decl (scope, name); 2446 } 2447 2448 /* Process local and global using-declarations. */ 2449 2450 static void 2451 do_nonmember_using_decl (tree scope, tree name, tree oldval, tree oldtype, 2452 tree *newval, tree *newtype) 2453 { 2454 struct scope_binding decls = EMPTY_SCOPE_BINDING; 2455 2456 *newval = *newtype = NULL_TREE; 2457 if (!qualified_lookup_using_namespace (name, scope, &decls, 0)) 2458 /* Lookup error */ 2459 return; 2460 2461 if (!decls.value && !decls.type) 2462 { 2463 error ("%qD not declared", name); 2464 return; 2465 } 2466 2467 /* Shift the old and new bindings around so we're comparing class and 2468 enumeration names to each other. */ 2469 if (oldval && DECL_IMPLICIT_TYPEDEF_P (oldval)) 2470 { 2471 oldtype = oldval; 2472 oldval = NULL_TREE; 2473 } 2474 2475 if (decls.value && DECL_IMPLICIT_TYPEDEF_P (decls.value)) 2476 { 2477 decls.type = decls.value; 2478 decls.value = NULL_TREE; 2479 } 2480 2481 /* It is impossible to overload a built-in function; any explicit 2482 declaration eliminates the built-in declaration. So, if OLDVAL 2483 is a built-in, then we can just pretend it isn't there. */ 2484 if (oldval 2485 && TREE_CODE (oldval) == FUNCTION_DECL 2486 && DECL_ANTICIPATED (oldval) 2487 && !DECL_HIDDEN_FRIEND_P (oldval)) 2488 oldval = NULL_TREE; 2489 2490 if (decls.value) 2491 { 2492 /* Check for using functions. */ 2493 if (is_overloaded_fn (decls.value)) 2494 { 2495 tree tmp, tmp1; 2496 2497 if (oldval && !is_overloaded_fn (oldval)) 2498 { 2499 error ("%qD is already declared in this scope", name); 2500 oldval = NULL_TREE; 2501 } 2502 2503 *newval = oldval; 2504 for (tmp = decls.value; tmp; tmp = OVL_NEXT (tmp)) 2505 { 2506 tree new_fn = OVL_CURRENT (tmp); 2507 2508 /* [namespace.udecl] 2509 2510 If a function declaration in namespace scope or block 2511 scope has the same name and the same parameter types as a 2512 function introduced by a using declaration the program is 2513 ill-formed. */ 2514 for (tmp1 = oldval; tmp1; tmp1 = OVL_NEXT (tmp1)) 2515 { 2516 tree old_fn = OVL_CURRENT (tmp1); 2517 2518 if (new_fn == old_fn) 2519 /* The function already exists in the current namespace. */ 2520 break; 2521 else if (OVL_USED (tmp1)) 2522 continue; /* this is a using decl */ 2523 else if (compparms (TYPE_ARG_TYPES (TREE_TYPE (new_fn)), 2524 TYPE_ARG_TYPES (TREE_TYPE (old_fn)))) 2525 { 2526 gcc_assert (!DECL_ANTICIPATED (old_fn) 2527 || DECL_HIDDEN_FRIEND_P (old_fn)); 2528 2529 /* There was already a non-using declaration in 2530 this scope with the same parameter types. If both 2531 are the same extern "C" functions, that's ok. */ 2532 if (decls_match (new_fn, old_fn)) 2533 break; 2534 else 2535 { 2536 error ("%qD is already declared in this scope", name); 2537 break; 2538 } 2539 } 2540 } 2541 2542 /* If we broke out of the loop, there's no reason to add 2543 this function to the using declarations for this 2544 scope. */ 2545 if (tmp1) 2546 continue; 2547 2548 /* If we are adding to an existing OVERLOAD, then we no 2549 longer know the type of the set of functions. */ 2550 if (*newval && TREE_CODE (*newval) == OVERLOAD) 2551 TREE_TYPE (*newval) = unknown_type_node; 2552 /* Add this new function to the set. */ 2553 *newval = build_overload (OVL_CURRENT (tmp), *newval); 2554 /* If there is only one function, then we use its type. (A 2555 using-declaration naming a single function can be used in 2556 contexts where overload resolution cannot be 2557 performed.) */ 2558 if (TREE_CODE (*newval) != OVERLOAD) 2559 { 2560 *newval = ovl_cons (*newval, NULL_TREE); 2561 TREE_TYPE (*newval) = TREE_TYPE (OVL_CURRENT (tmp)); 2562 } 2563 OVL_USED (*newval) = 1; 2564 } 2565 } 2566 else 2567 { 2568 *newval = decls.value; 2569 if (oldval && !decls_match (*newval, oldval)) 2570 error ("%qD is already declared in this scope", name); 2571 } 2572 } 2573 else 2574 *newval = oldval; 2575 2576 if (decls.type && TREE_CODE (decls.type) == TREE_LIST) 2577 { 2578 error ("reference to %qD is ambiguous", name); 2579 print_candidates (decls.type); 2580 } 2581 else 2582 { 2583 *newtype = decls.type; 2584 if (oldtype && *newtype && !decls_match (oldtype, *newtype)) 2585 error ("%qD is already declared in this scope", name); 2586 } 2587 2588 /* If *newval is empty, shift any class or enumeration name down. */ 2589 if (!*newval) 2590 { 2591 *newval = *newtype; 2592 *newtype = NULL_TREE; 2593 } 2594 } 2595 2596 /* Process a using-declaration at function scope. */ 2597 2598 void 2599 do_local_using_decl (tree decl, tree scope, tree name) 2600 { 2601 tree oldval, oldtype, newval, newtype; 2602 tree orig_decl = decl; 2603 2604 decl = validate_nonmember_using_decl (decl, scope, name); 2605 if (decl == NULL_TREE) 2606 return; 2607 2608 if (building_stmt_list_p () 2609 && at_function_scope_p ()) 2610 add_decl_expr (decl); 2611 2612 oldval = lookup_name_innermost_nonclass_level (name); 2613 oldtype = lookup_type_current_level (name); 2614 2615 do_nonmember_using_decl (scope, name, oldval, oldtype, &newval, &newtype); 2616 2617 if (newval) 2618 { 2619 if (is_overloaded_fn (newval)) 2620 { 2621 tree fn, term; 2622 2623 /* We only need to push declarations for those functions 2624 that were not already bound in the current level. 2625 The old value might be NULL_TREE, it might be a single 2626 function, or an OVERLOAD. */ 2627 if (oldval && TREE_CODE (oldval) == OVERLOAD) 2628 term = OVL_FUNCTION (oldval); 2629 else 2630 term = oldval; 2631 for (fn = newval; fn && OVL_CURRENT (fn) != term; 2632 fn = OVL_NEXT (fn)) 2633 push_overloaded_decl (OVL_CURRENT (fn), 2634 PUSH_LOCAL | PUSH_USING, 2635 false); 2636 } 2637 else 2638 push_local_binding (name, newval, PUSH_USING); 2639 } 2640 if (newtype) 2641 { 2642 push_local_binding (name, newtype, PUSH_USING); 2643 set_identifier_type_value (name, newtype); 2644 } 2645 2646 /* Emit debug info. */ 2647 if (!processing_template_decl) 2648 cp_emit_debug_info_for_using (orig_decl, current_scope()); 2649 } 2650 2651 /* Returns true if ROOT (a namespace, class, or function) encloses 2652 CHILD. CHILD may be either a class type or a namespace. */ 2653 2654 bool 2655 is_ancestor (tree root, tree child) 2656 { 2657 gcc_assert ((TREE_CODE (root) == NAMESPACE_DECL 2658 || TREE_CODE (root) == FUNCTION_DECL 2659 || CLASS_TYPE_P (root))); 2660 gcc_assert ((TREE_CODE (child) == NAMESPACE_DECL 2661 || CLASS_TYPE_P (child))); 2662 2663 /* The global namespace encloses everything. */ 2664 if (root == global_namespace) 2665 return true; 2666 2667 while (true) 2668 { 2669 /* If we've run out of scopes, stop. */ 2670 if (!child) 2671 return false; 2672 /* If we've reached the ROOT, it encloses CHILD. */ 2673 if (root == child) 2674 return true; 2675 /* Go out one level. */ 2676 if (TYPE_P (child)) 2677 child = TYPE_NAME (child); 2678 child = DECL_CONTEXT (child); 2679 } 2680 } 2681 2682 /* Enter the class or namespace scope indicated by T suitable for name 2683 lookup. T can be arbitrary scope, not necessary nested inside the 2684 current scope. Returns a non-null scope to pop iff pop_scope 2685 should be called later to exit this scope. */ 2686 2687 tree 2688 push_scope (tree t) 2689 { 2690 if (TREE_CODE (t) == NAMESPACE_DECL) 2691 push_decl_namespace (t); 2692 else if (CLASS_TYPE_P (t)) 2693 { 2694 if (!at_class_scope_p () 2695 || !same_type_p (current_class_type, t)) 2696 push_nested_class (t); 2697 else 2698 /* T is the same as the current scope. There is therefore no 2699 need to re-enter the scope. Since we are not actually 2700 pushing a new scope, our caller should not call 2701 pop_scope. */ 2702 t = NULL_TREE; 2703 } 2704 2705 return t; 2706 } 2707 2708 /* Leave scope pushed by push_scope. */ 2709 2710 void 2711 pop_scope (tree t) 2712 { 2713 if (t == NULL_TREE) 2714 return; 2715 if (TREE_CODE (t) == NAMESPACE_DECL) 2716 pop_decl_namespace (); 2717 else if CLASS_TYPE_P (t) 2718 pop_nested_class (); 2719 } 2720 2721 /* Subroutine of push_inner_scope. */ 2722 2723 static void 2724 push_inner_scope_r (tree outer, tree inner) 2725 { 2726 tree prev; 2727 2728 if (outer == inner 2729 || (TREE_CODE (inner) != NAMESPACE_DECL && !CLASS_TYPE_P (inner))) 2730 return; 2731 2732 prev = CP_DECL_CONTEXT (TREE_CODE (inner) == NAMESPACE_DECL ? inner : TYPE_NAME (inner)); 2733 if (outer != prev) 2734 push_inner_scope_r (outer, prev); 2735 if (TREE_CODE (inner) == NAMESPACE_DECL) 2736 { 2737 cp_binding_level *save_template_parm = 0; 2738 /* Temporary take out template parameter scopes. They are saved 2739 in reversed order in save_template_parm. */ 2740 while (current_binding_level->kind == sk_template_parms) 2741 { 2742 cp_binding_level *b = current_binding_level; 2743 current_binding_level = b->level_chain; 2744 b->level_chain = save_template_parm; 2745 save_template_parm = b; 2746 } 2747 2748 resume_scope (NAMESPACE_LEVEL (inner)); 2749 current_namespace = inner; 2750 2751 /* Restore template parameter scopes. */ 2752 while (save_template_parm) 2753 { 2754 cp_binding_level *b = save_template_parm; 2755 save_template_parm = b->level_chain; 2756 b->level_chain = current_binding_level; 2757 current_binding_level = b; 2758 } 2759 } 2760 else 2761 pushclass (inner); 2762 } 2763 2764 /* Enter the scope INNER from current scope. INNER must be a scope 2765 nested inside current scope. This works with both name lookup and 2766 pushing name into scope. In case a template parameter scope is present, 2767 namespace is pushed under the template parameter scope according to 2768 name lookup rule in 14.6.1/6. 2769 2770 Return the former current scope suitable for pop_inner_scope. */ 2771 2772 tree 2773 push_inner_scope (tree inner) 2774 { 2775 tree outer = current_scope (); 2776 if (!outer) 2777 outer = current_namespace; 2778 2779 push_inner_scope_r (outer, inner); 2780 return outer; 2781 } 2782 2783 /* Exit the current scope INNER back to scope OUTER. */ 2784 2785 void 2786 pop_inner_scope (tree outer, tree inner) 2787 { 2788 if (outer == inner 2789 || (TREE_CODE (inner) != NAMESPACE_DECL && !CLASS_TYPE_P (inner))) 2790 return; 2791 2792 while (outer != inner) 2793 { 2794 if (TREE_CODE (inner) == NAMESPACE_DECL) 2795 { 2796 cp_binding_level *save_template_parm = 0; 2797 /* Temporary take out template parameter scopes. They are saved 2798 in reversed order in save_template_parm. */ 2799 while (current_binding_level->kind == sk_template_parms) 2800 { 2801 cp_binding_level *b = current_binding_level; 2802 current_binding_level = b->level_chain; 2803 b->level_chain = save_template_parm; 2804 save_template_parm = b; 2805 } 2806 2807 pop_namespace (); 2808 2809 /* Restore template parameter scopes. */ 2810 while (save_template_parm) 2811 { 2812 cp_binding_level *b = save_template_parm; 2813 save_template_parm = b->level_chain; 2814 b->level_chain = current_binding_level; 2815 current_binding_level = b; 2816 } 2817 } 2818 else 2819 popclass (); 2820 2821 inner = CP_DECL_CONTEXT (TREE_CODE (inner) == NAMESPACE_DECL ? inner : TYPE_NAME (inner)); 2822 } 2823 } 2824 2825 /* Do a pushlevel for class declarations. */ 2826 2827 void 2828 pushlevel_class (void) 2829 { 2830 class_binding_level = begin_scope (sk_class, current_class_type); 2831 } 2832 2833 /* ...and a poplevel for class declarations. */ 2834 2835 void 2836 poplevel_class (void) 2837 { 2838 cp_binding_level *level = class_binding_level; 2839 cp_class_binding *cb; 2840 size_t i; 2841 tree shadowed; 2842 2843 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 2844 gcc_assert (level != 0); 2845 2846 /* If we're leaving a toplevel class, cache its binding level. */ 2847 if (current_class_depth == 1) 2848 previous_class_level = level; 2849 for (shadowed = level->type_shadowed; 2850 shadowed; 2851 shadowed = TREE_CHAIN (shadowed)) 2852 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (shadowed), TREE_VALUE (shadowed)); 2853 2854 /* Remove the bindings for all of the class-level declarations. */ 2855 if (level->class_shadowed) 2856 { 2857 FOR_EACH_VEC_ELT (cp_class_binding, level->class_shadowed, i, cb) 2858 { 2859 IDENTIFIER_BINDING (cb->identifier) = cb->base->previous; 2860 cxx_binding_free (cb->base); 2861 } 2862 ggc_free (level->class_shadowed); 2863 level->class_shadowed = NULL; 2864 } 2865 2866 /* Now, pop out of the binding level which we created up in the 2867 `pushlevel_class' routine. */ 2868 gcc_assert (current_binding_level == level); 2869 leave_scope (); 2870 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 2871 } 2872 2873 /* Set INHERITED_VALUE_BINDING_P on BINDING to true or false, as 2874 appropriate. DECL is the value to which a name has just been 2875 bound. CLASS_TYPE is the class in which the lookup occurred. */ 2876 2877 static void 2878 set_inherited_value_binding_p (cxx_binding *binding, tree decl, 2879 tree class_type) 2880 { 2881 if (binding->value == decl && TREE_CODE (decl) != TREE_LIST) 2882 { 2883 tree context; 2884 2885 if (TREE_CODE (decl) == OVERLOAD) 2886 context = ovl_scope (decl); 2887 else 2888 { 2889 gcc_assert (DECL_P (decl)); 2890 context = context_for_name_lookup (decl); 2891 } 2892 2893 if (is_properly_derived_from (class_type, context)) 2894 INHERITED_VALUE_BINDING_P (binding) = 1; 2895 else 2896 INHERITED_VALUE_BINDING_P (binding) = 0; 2897 } 2898 else if (binding->value == decl) 2899 /* We only encounter a TREE_LIST when there is an ambiguity in the 2900 base classes. Such an ambiguity can be overridden by a 2901 definition in this class. */ 2902 INHERITED_VALUE_BINDING_P (binding) = 1; 2903 else 2904 INHERITED_VALUE_BINDING_P (binding) = 0; 2905 } 2906 2907 /* Make the declaration of X appear in CLASS scope. */ 2908 2909 bool 2910 pushdecl_class_level (tree x) 2911 { 2912 tree name; 2913 bool is_valid = true; 2914 bool subtime; 2915 2916 /* Do nothing if we're adding to an outer lambda closure type, 2917 outer_binding will add it later if it's needed. */ 2918 if (current_class_type != class_binding_level->this_entity) 2919 return true; 2920 2921 subtime = timevar_cond_start (TV_NAME_LOOKUP); 2922 /* Get the name of X. */ 2923 if (TREE_CODE (x) == OVERLOAD) 2924 name = DECL_NAME (get_first_fn (x)); 2925 else 2926 name = DECL_NAME (x); 2927 2928 if (name) 2929 { 2930 is_valid = push_class_level_binding (name, x); 2931 if (TREE_CODE (x) == TYPE_DECL) 2932 set_identifier_type_value (name, x); 2933 } 2934 else if (ANON_AGGR_TYPE_P (TREE_TYPE (x))) 2935 { 2936 /* If X is an anonymous aggregate, all of its members are 2937 treated as if they were members of the class containing the 2938 aggregate, for naming purposes. */ 2939 tree f; 2940 2941 for (f = TYPE_FIELDS (TREE_TYPE (x)); f; f = DECL_CHAIN (f)) 2942 { 2943 location_t save_location = input_location; 2944 input_location = DECL_SOURCE_LOCATION (f); 2945 if (!pushdecl_class_level (f)) 2946 is_valid = false; 2947 input_location = save_location; 2948 } 2949 } 2950 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 2951 return is_valid; 2952 } 2953 2954 /* Return the BINDING (if any) for NAME in SCOPE, which is a class 2955 scope. If the value returned is non-NULL, and the PREVIOUS field 2956 is not set, callers must set the PREVIOUS field explicitly. */ 2957 2958 static cxx_binding * 2959 get_class_binding (tree name, cp_binding_level *scope) 2960 { 2961 tree class_type; 2962 tree type_binding; 2963 tree value_binding; 2964 cxx_binding *binding; 2965 2966 class_type = scope->this_entity; 2967 2968 /* Get the type binding. */ 2969 type_binding = lookup_member (class_type, name, 2970 /*protect=*/2, /*want_type=*/true, 2971 tf_warning_or_error); 2972 /* Get the value binding. */ 2973 value_binding = lookup_member (class_type, name, 2974 /*protect=*/2, /*want_type=*/false, 2975 tf_warning_or_error); 2976 2977 if (value_binding 2978 && (TREE_CODE (value_binding) == TYPE_DECL 2979 || DECL_CLASS_TEMPLATE_P (value_binding) 2980 || (TREE_CODE (value_binding) == TREE_LIST 2981 && TREE_TYPE (value_binding) == error_mark_node 2982 && (TREE_CODE (TREE_VALUE (value_binding)) 2983 == TYPE_DECL)))) 2984 /* We found a type binding, even when looking for a non-type 2985 binding. This means that we already processed this binding 2986 above. */ 2987 ; 2988 else if (value_binding) 2989 { 2990 if (TREE_CODE (value_binding) == TREE_LIST 2991 && TREE_TYPE (value_binding) == error_mark_node) 2992 /* NAME is ambiguous. */ 2993 ; 2994 else if (BASELINK_P (value_binding)) 2995 /* NAME is some overloaded functions. */ 2996 value_binding = BASELINK_FUNCTIONS (value_binding); 2997 } 2998 2999 /* If we found either a type binding or a value binding, create a 3000 new binding object. */ 3001 if (type_binding || value_binding) 3002 { 3003 binding = new_class_binding (name, 3004 value_binding, 3005 type_binding, 3006 scope); 3007 /* This is a class-scope binding, not a block-scope binding. */ 3008 LOCAL_BINDING_P (binding) = 0; 3009 set_inherited_value_binding_p (binding, value_binding, class_type); 3010 } 3011 else 3012 binding = NULL; 3013 3014 return binding; 3015 } 3016 3017 /* Make the declaration(s) of X appear in CLASS scope under the name 3018 NAME. Returns true if the binding is valid. */ 3019 3020 static bool 3021 push_class_level_binding_1 (tree name, tree x) 3022 { 3023 cxx_binding *binding; 3024 tree decl = x; 3025 bool ok; 3026 3027 /* The class_binding_level will be NULL if x is a template 3028 parameter name in a member template. */ 3029 if (!class_binding_level) 3030 return true; 3031 3032 if (name == error_mark_node) 3033 return false; 3034 3035 /* Check for invalid member names. */ 3036 gcc_assert (TYPE_BEING_DEFINED (current_class_type)); 3037 /* Check that we're pushing into the right binding level. */ 3038 gcc_assert (current_class_type == class_binding_level->this_entity); 3039 3040 /* We could have been passed a tree list if this is an ambiguous 3041 declaration. If so, pull the declaration out because 3042 check_template_shadow will not handle a TREE_LIST. */ 3043 if (TREE_CODE (decl) == TREE_LIST 3044 && TREE_TYPE (decl) == error_mark_node) 3045 decl = TREE_VALUE (decl); 3046 3047 if (!check_template_shadow (decl)) 3048 return false; 3049 3050 /* [class.mem] 3051 3052 If T is the name of a class, then each of the following shall 3053 have a name different from T: 3054 3055 -- every static data member of class T; 3056 3057 -- every member of class T that is itself a type; 3058 3059 -- every enumerator of every member of class T that is an 3060 enumerated type; 3061 3062 -- every member of every anonymous union that is a member of 3063 class T. 3064 3065 (Non-static data members were also forbidden to have the same 3066 name as T until TC1.) */ 3067 if ((TREE_CODE (x) == VAR_DECL 3068 || TREE_CODE (x) == CONST_DECL 3069 || (TREE_CODE (x) == TYPE_DECL 3070 && !DECL_SELF_REFERENCE_P (x)) 3071 /* A data member of an anonymous union. */ 3072 || (TREE_CODE (x) == FIELD_DECL 3073 && DECL_CONTEXT (x) != current_class_type)) 3074 && DECL_NAME (x) == constructor_name (current_class_type)) 3075 { 3076 tree scope = context_for_name_lookup (x); 3077 if (TYPE_P (scope) && same_type_p (scope, current_class_type)) 3078 { 3079 error ("%qD has the same name as the class in which it is " 3080 "declared", 3081 x); 3082 return false; 3083 } 3084 } 3085 3086 /* Get the current binding for NAME in this class, if any. */ 3087 binding = IDENTIFIER_BINDING (name); 3088 if (!binding || binding->scope != class_binding_level) 3089 { 3090 binding = get_class_binding (name, class_binding_level); 3091 /* If a new binding was created, put it at the front of the 3092 IDENTIFIER_BINDING list. */ 3093 if (binding) 3094 { 3095 binding->previous = IDENTIFIER_BINDING (name); 3096 IDENTIFIER_BINDING (name) = binding; 3097 } 3098 } 3099 3100 /* If there is already a binding, then we may need to update the 3101 current value. */ 3102 if (binding && binding->value) 3103 { 3104 tree bval = binding->value; 3105 tree old_decl = NULL_TREE; 3106 tree target_decl = strip_using_decl (decl); 3107 tree target_bval = strip_using_decl (bval); 3108 3109 if (INHERITED_VALUE_BINDING_P (binding)) 3110 { 3111 /* If the old binding was from a base class, and was for a 3112 tag name, slide it over to make room for the new binding. 3113 The old binding is still visible if explicitly qualified 3114 with a class-key. */ 3115 if (TREE_CODE (target_bval) == TYPE_DECL 3116 && DECL_ARTIFICIAL (target_bval) 3117 && !(TREE_CODE (target_decl) == TYPE_DECL 3118 && DECL_ARTIFICIAL (target_decl))) 3119 { 3120 old_decl = binding->type; 3121 binding->type = bval; 3122 binding->value = NULL_TREE; 3123 INHERITED_VALUE_BINDING_P (binding) = 0; 3124 } 3125 else 3126 { 3127 old_decl = bval; 3128 /* Any inherited type declaration is hidden by the type 3129 declaration in the derived class. */ 3130 if (TREE_CODE (target_decl) == TYPE_DECL 3131 && DECL_ARTIFICIAL (target_decl)) 3132 binding->type = NULL_TREE; 3133 } 3134 } 3135 else if (TREE_CODE (target_decl) == OVERLOAD 3136 && is_overloaded_fn (target_bval)) 3137 old_decl = bval; 3138 else if (TREE_CODE (decl) == USING_DECL 3139 && TREE_CODE (bval) == USING_DECL 3140 && same_type_p (USING_DECL_SCOPE (decl), 3141 USING_DECL_SCOPE (bval))) 3142 /* This is a using redeclaration that will be diagnosed later 3143 in supplement_binding */ 3144 ; 3145 else if (TREE_CODE (decl) == USING_DECL 3146 && TREE_CODE (bval) == USING_DECL 3147 && DECL_DEPENDENT_P (decl) 3148 && DECL_DEPENDENT_P (bval)) 3149 return true; 3150 else if (TREE_CODE (decl) == USING_DECL 3151 && is_overloaded_fn (target_bval)) 3152 old_decl = bval; 3153 else if (TREE_CODE (bval) == USING_DECL 3154 && is_overloaded_fn (target_decl)) 3155 return true; 3156 3157 if (old_decl && binding->scope == class_binding_level) 3158 { 3159 binding->value = x; 3160 /* It is always safe to clear INHERITED_VALUE_BINDING_P 3161 here. This function is only used to register bindings 3162 from with the class definition itself. */ 3163 INHERITED_VALUE_BINDING_P (binding) = 0; 3164 return true; 3165 } 3166 } 3167 3168 /* Note that we declared this value so that we can issue an error if 3169 this is an invalid redeclaration of a name already used for some 3170 other purpose. */ 3171 note_name_declared_in_class (name, decl); 3172 3173 /* If we didn't replace an existing binding, put the binding on the 3174 stack of bindings for the identifier, and update the shadowed 3175 list. */ 3176 if (binding && binding->scope == class_binding_level) 3177 /* Supplement the existing binding. */ 3178 ok = supplement_binding (binding, decl); 3179 else 3180 { 3181 /* Create a new binding. */ 3182 push_binding (name, decl, class_binding_level); 3183 ok = true; 3184 } 3185 3186 return ok; 3187 } 3188 3189 /* Wrapper for push_class_level_binding_1. */ 3190 3191 bool 3192 push_class_level_binding (tree name, tree x) 3193 { 3194 bool ret; 3195 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 3196 ret = push_class_level_binding_1 (name, x); 3197 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 3198 return ret; 3199 } 3200 3201 /* Process "using SCOPE::NAME" in a class scope. Return the 3202 USING_DECL created. */ 3203 3204 tree 3205 do_class_using_decl (tree scope, tree name) 3206 { 3207 /* The USING_DECL returned by this function. */ 3208 tree value; 3209 /* The declaration (or declarations) name by this using 3210 declaration. NULL if we are in a template and cannot figure out 3211 what has been named. */ 3212 tree decl; 3213 /* True if SCOPE is a dependent type. */ 3214 bool scope_dependent_p; 3215 /* True if SCOPE::NAME is dependent. */ 3216 bool name_dependent_p; 3217 /* True if any of the bases of CURRENT_CLASS_TYPE are dependent. */ 3218 bool bases_dependent_p; 3219 tree binfo; 3220 tree base_binfo; 3221 int i; 3222 3223 if (name == error_mark_node) 3224 return NULL_TREE; 3225 3226 if (!scope || !TYPE_P (scope)) 3227 { 3228 error ("using-declaration for non-member at class scope"); 3229 return NULL_TREE; 3230 } 3231 3232 /* Make sure the name is not invalid */ 3233 if (TREE_CODE (name) == BIT_NOT_EXPR) 3234 { 3235 error ("%<%T::%D%> names destructor", scope, name); 3236 return NULL_TREE; 3237 } 3238 if (MAYBE_CLASS_TYPE_P (scope) && constructor_name_p (name, scope)) 3239 { 3240 error ("%<%T::%D%> names constructor", scope, name); 3241 return NULL_TREE; 3242 } 3243 if (constructor_name_p (name, current_class_type)) 3244 { 3245 error ("%<%T::%D%> names constructor in %qT", 3246 scope, name, current_class_type); 3247 return NULL_TREE; 3248 } 3249 3250 scope_dependent_p = dependent_scope_p (scope); 3251 name_dependent_p = (scope_dependent_p 3252 || (IDENTIFIER_TYPENAME_P (name) 3253 && dependent_type_p (TREE_TYPE (name)))); 3254 3255 bases_dependent_p = false; 3256 if (processing_template_decl) 3257 for (binfo = TYPE_BINFO (current_class_type), i = 0; 3258 BINFO_BASE_ITERATE (binfo, i, base_binfo); 3259 i++) 3260 if (dependent_type_p (TREE_TYPE (base_binfo))) 3261 { 3262 bases_dependent_p = true; 3263 break; 3264 } 3265 3266 decl = NULL_TREE; 3267 3268 /* From [namespace.udecl]: 3269 3270 A using-declaration used as a member-declaration shall refer to a 3271 member of a base class of the class being defined. 3272 3273 In general, we cannot check this constraint in a template because 3274 we do not know the entire set of base classes of the current 3275 class type. Morover, if SCOPE is dependent, it might match a 3276 non-dependent base. */ 3277 3278 if (!scope_dependent_p) 3279 { 3280 base_kind b_kind; 3281 binfo = lookup_base (current_class_type, scope, ba_any, &b_kind); 3282 if (b_kind < bk_proper_base) 3283 { 3284 if (!bases_dependent_p) 3285 { 3286 error_not_base_type (scope, current_class_type); 3287 return NULL_TREE; 3288 } 3289 } 3290 else if (!name_dependent_p) 3291 { 3292 decl = lookup_member (binfo, name, 0, false, tf_warning_or_error); 3293 if (!decl) 3294 { 3295 error ("no members matching %<%T::%D%> in %q#T", scope, name, 3296 scope); 3297 return NULL_TREE; 3298 } 3299 /* The binfo from which the functions came does not matter. */ 3300 if (BASELINK_P (decl)) 3301 decl = BASELINK_FUNCTIONS (decl); 3302 } 3303 } 3304 3305 value = build_lang_decl (USING_DECL, name, NULL_TREE); 3306 USING_DECL_DECLS (value) = decl; 3307 USING_DECL_SCOPE (value) = scope; 3308 DECL_DEPENDENT_P (value) = !decl; 3309 3310 return value; 3311 } 3312 3313 3314 /* Return the binding value for name in scope. */ 3315 3316 3317 static tree 3318 namespace_binding_1 (tree name, tree scope) 3319 { 3320 cxx_binding *binding; 3321 3322 if (SCOPE_FILE_SCOPE_P (scope)) 3323 scope = global_namespace; 3324 else 3325 /* Unnecessary for the global namespace because it can't be an alias. */ 3326 scope = ORIGINAL_NAMESPACE (scope); 3327 3328 binding = cp_binding_level_find_binding_for_name (NAMESPACE_LEVEL (scope), name); 3329 3330 return binding ? binding->value : NULL_TREE; 3331 } 3332 3333 tree 3334 namespace_binding (tree name, tree scope) 3335 { 3336 tree ret; 3337 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 3338 ret = namespace_binding_1 (name, scope); 3339 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 3340 return ret; 3341 } 3342 3343 /* Set the binding value for name in scope. */ 3344 3345 static void 3346 set_namespace_binding_1 (tree name, tree scope, tree val) 3347 { 3348 cxx_binding *b; 3349 3350 if (scope == NULL_TREE) 3351 scope = global_namespace; 3352 b = binding_for_name (NAMESPACE_LEVEL (scope), name); 3353 if (!b->value || TREE_CODE (val) == OVERLOAD || val == error_mark_node) 3354 b->value = val; 3355 else 3356 supplement_binding (b, val); 3357 } 3358 3359 /* Wrapper for set_namespace_binding_1. */ 3360 3361 void 3362 set_namespace_binding (tree name, tree scope, tree val) 3363 { 3364 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 3365 set_namespace_binding_1 (name, scope, val); 3366 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 3367 } 3368 3369 /* Set the context of a declaration to scope. Complain if we are not 3370 outside scope. */ 3371 3372 void 3373 set_decl_namespace (tree decl, tree scope, bool friendp) 3374 { 3375 tree old; 3376 3377 /* Get rid of namespace aliases. */ 3378 scope = ORIGINAL_NAMESPACE (scope); 3379 3380 /* It is ok for friends to be qualified in parallel space. */ 3381 if (!friendp && !is_ancestor (current_namespace, scope)) 3382 error ("declaration of %qD not in a namespace surrounding %qD", 3383 decl, scope); 3384 DECL_CONTEXT (decl) = FROB_CONTEXT (scope); 3385 3386 /* Writing "int N::i" to declare a variable within "N" is invalid. */ 3387 if (scope == current_namespace) 3388 { 3389 if (at_namespace_scope_p ()) 3390 error ("explicit qualification in declaration of %qD", 3391 decl); 3392 return; 3393 } 3394 3395 /* See whether this has been declared in the namespace. */ 3396 old = lookup_qualified_name (scope, DECL_NAME (decl), false, true); 3397 if (old == error_mark_node) 3398 /* No old declaration at all. */ 3399 goto complain; 3400 /* If it's a TREE_LIST, the result of the lookup was ambiguous. */ 3401 if (TREE_CODE (old) == TREE_LIST) 3402 { 3403 error ("reference to %qD is ambiguous", decl); 3404 print_candidates (old); 3405 return; 3406 } 3407 if (!is_overloaded_fn (decl)) 3408 { 3409 /* We might have found OLD in an inline namespace inside SCOPE. */ 3410 if (TREE_CODE (decl) == TREE_CODE (old)) 3411 DECL_CONTEXT (decl) = DECL_CONTEXT (old); 3412 /* Don't compare non-function decls with decls_match here, since 3413 it can't check for the correct constness at this 3414 point. pushdecl will find those errors later. */ 3415 return; 3416 } 3417 /* Since decl is a function, old should contain a function decl. */ 3418 if (!is_overloaded_fn (old)) 3419 goto complain; 3420 /* A template can be explicitly specialized in any namespace. */ 3421 if (processing_explicit_instantiation) 3422 return; 3423 if (processing_template_decl || processing_specialization) 3424 /* We have not yet called push_template_decl to turn a 3425 FUNCTION_DECL into a TEMPLATE_DECL, so the declarations won't 3426 match. But, we'll check later, when we construct the 3427 template. */ 3428 return; 3429 /* Instantiations or specializations of templates may be declared as 3430 friends in any namespace. */ 3431 if (friendp && DECL_USE_TEMPLATE (decl)) 3432 return; 3433 if (is_overloaded_fn (old)) 3434 { 3435 tree found = NULL_TREE; 3436 tree elt = old; 3437 for (; elt; elt = OVL_NEXT (elt)) 3438 { 3439 tree ofn = OVL_CURRENT (elt); 3440 /* Adjust DECL_CONTEXT first so decls_match will return true 3441 if DECL will match a declaration in an inline namespace. */ 3442 DECL_CONTEXT (decl) = DECL_CONTEXT (ofn); 3443 if (decls_match (decl, ofn)) 3444 { 3445 if (found && !decls_match (found, ofn)) 3446 { 3447 DECL_CONTEXT (decl) = FROB_CONTEXT (scope); 3448 error ("reference to %qD is ambiguous", decl); 3449 print_candidates (old); 3450 return; 3451 } 3452 found = ofn; 3453 } 3454 } 3455 if (found) 3456 { 3457 if (!is_associated_namespace (scope, CP_DECL_CONTEXT (found))) 3458 goto complain; 3459 DECL_CONTEXT (decl) = DECL_CONTEXT (found); 3460 return; 3461 } 3462 } 3463 else 3464 { 3465 DECL_CONTEXT (decl) = DECL_CONTEXT (old); 3466 if (decls_match (decl, old)) 3467 return; 3468 } 3469 3470 /* It didn't work, go back to the explicit scope. */ 3471 DECL_CONTEXT (decl) = FROB_CONTEXT (scope); 3472 complain: 3473 error ("%qD should have been declared inside %qD", decl, scope); 3474 } 3475 3476 /* Return the namespace where the current declaration is declared. */ 3477 3478 tree 3479 current_decl_namespace (void) 3480 { 3481 tree result; 3482 /* If we have been pushed into a different namespace, use it. */ 3483 if (!VEC_empty (tree, decl_namespace_list)) 3484 return VEC_last (tree, decl_namespace_list); 3485 3486 if (current_class_type) 3487 result = decl_namespace_context (current_class_type); 3488 else if (current_function_decl) 3489 result = decl_namespace_context (current_function_decl); 3490 else 3491 result = current_namespace; 3492 return result; 3493 } 3494 3495 /* Process any ATTRIBUTES on a namespace definition. Currently only 3496 attribute visibility is meaningful, which is a property of the syntactic 3497 block rather than the namespace as a whole, so we don't touch the 3498 NAMESPACE_DECL at all. Returns true if attribute visibility is seen. */ 3499 3500 bool 3501 handle_namespace_attrs (tree ns, tree attributes) 3502 { 3503 tree d; 3504 bool saw_vis = false; 3505 3506 for (d = attributes; d; d = TREE_CHAIN (d)) 3507 { 3508 tree name = TREE_PURPOSE (d); 3509 tree args = TREE_VALUE (d); 3510 3511 if (is_attribute_p ("visibility", name)) 3512 { 3513 tree x = args ? TREE_VALUE (args) : NULL_TREE; 3514 if (x == NULL_TREE || TREE_CODE (x) != STRING_CST || TREE_CHAIN (args)) 3515 { 3516 warning (OPT_Wattributes, 3517 "%qD attribute requires a single NTBS argument", 3518 name); 3519 continue; 3520 } 3521 3522 if (!TREE_PUBLIC (ns)) 3523 warning (OPT_Wattributes, 3524 "%qD attribute is meaningless since members of the " 3525 "anonymous namespace get local symbols", name); 3526 3527 push_visibility (TREE_STRING_POINTER (x), 1); 3528 saw_vis = true; 3529 } 3530 else 3531 { 3532 warning (OPT_Wattributes, "%qD attribute directive ignored", 3533 name); 3534 continue; 3535 } 3536 } 3537 3538 return saw_vis; 3539 } 3540 3541 /* Push into the scope of the NAME namespace. If NAME is NULL_TREE, then we 3542 select a name that is unique to this compilation unit. */ 3543 3544 void 3545 push_namespace (tree name) 3546 { 3547 tree d = NULL_TREE; 3548 int need_new = 1; 3549 int implicit_use = 0; 3550 bool anon = !name; 3551 3552 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 3553 3554 /* We should not get here if the global_namespace is not yet constructed 3555 nor if NAME designates the global namespace: The global scope is 3556 constructed elsewhere. */ 3557 gcc_assert (global_namespace != NULL && name != global_scope_name); 3558 3559 if (anon) 3560 { 3561 name = get_anonymous_namespace_name(); 3562 d = IDENTIFIER_NAMESPACE_VALUE (name); 3563 if (d) 3564 /* Reopening anonymous namespace. */ 3565 need_new = 0; 3566 implicit_use = 1; 3567 } 3568 else 3569 { 3570 /* Check whether this is an extended namespace definition. */ 3571 d = IDENTIFIER_NAMESPACE_VALUE (name); 3572 if (d != NULL_TREE && TREE_CODE (d) == NAMESPACE_DECL) 3573 { 3574 need_new = 0; 3575 if (DECL_NAMESPACE_ALIAS (d)) 3576 { 3577 error ("namespace alias %qD not allowed here, assuming %qD", 3578 d, DECL_NAMESPACE_ALIAS (d)); 3579 d = DECL_NAMESPACE_ALIAS (d); 3580 } 3581 } 3582 } 3583 3584 if (need_new) 3585 { 3586 /* Make a new namespace, binding the name to it. */ 3587 d = build_lang_decl (NAMESPACE_DECL, name, void_type_node); 3588 DECL_CONTEXT (d) = FROB_CONTEXT (current_namespace); 3589 /* The name of this namespace is not visible to other translation 3590 units if it is an anonymous namespace or member thereof. */ 3591 if (anon || decl_anon_ns_mem_p (current_namespace)) 3592 TREE_PUBLIC (d) = 0; 3593 else 3594 TREE_PUBLIC (d) = 1; 3595 pushdecl (d); 3596 if (anon) 3597 { 3598 /* Clear DECL_NAME for the benefit of debugging back ends. */ 3599 SET_DECL_ASSEMBLER_NAME (d, name); 3600 DECL_NAME (d) = NULL_TREE; 3601 } 3602 begin_scope (sk_namespace, d); 3603 } 3604 else 3605 resume_scope (NAMESPACE_LEVEL (d)); 3606 3607 if (implicit_use) 3608 do_using_directive (d); 3609 /* Enter the name space. */ 3610 current_namespace = d; 3611 3612 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 3613 } 3614 3615 /* Pop from the scope of the current namespace. */ 3616 3617 void 3618 pop_namespace (void) 3619 { 3620 gcc_assert (current_namespace != global_namespace); 3621 current_namespace = CP_DECL_CONTEXT (current_namespace); 3622 /* The binding level is not popped, as it might be re-opened later. */ 3623 leave_scope (); 3624 } 3625 3626 /* Push into the scope of the namespace NS, even if it is deeply 3627 nested within another namespace. */ 3628 3629 void 3630 push_nested_namespace (tree ns) 3631 { 3632 if (ns == global_namespace) 3633 push_to_top_level (); 3634 else 3635 { 3636 push_nested_namespace (CP_DECL_CONTEXT (ns)); 3637 push_namespace (DECL_NAME (ns)); 3638 } 3639 } 3640 3641 /* Pop back from the scope of the namespace NS, which was previously 3642 entered with push_nested_namespace. */ 3643 3644 void 3645 pop_nested_namespace (tree ns) 3646 { 3647 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 3648 gcc_assert (current_namespace == ns); 3649 while (ns != global_namespace) 3650 { 3651 pop_namespace (); 3652 ns = CP_DECL_CONTEXT (ns); 3653 } 3654 3655 pop_from_top_level (); 3656 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 3657 } 3658 3659 /* Temporarily set the namespace for the current declaration. */ 3660 3661 void 3662 push_decl_namespace (tree decl) 3663 { 3664 if (TREE_CODE (decl) != NAMESPACE_DECL) 3665 decl = decl_namespace_context (decl); 3666 VEC_safe_push (tree, gc, decl_namespace_list, ORIGINAL_NAMESPACE (decl)); 3667 } 3668 3669 /* [namespace.memdef]/2 */ 3670 3671 void 3672 pop_decl_namespace (void) 3673 { 3674 VEC_pop (tree, decl_namespace_list); 3675 } 3676 3677 /* Return the namespace that is the common ancestor 3678 of two given namespaces. */ 3679 3680 static tree 3681 namespace_ancestor_1 (tree ns1, tree ns2) 3682 { 3683 tree nsr; 3684 if (is_ancestor (ns1, ns2)) 3685 nsr = ns1; 3686 else 3687 nsr = namespace_ancestor_1 (CP_DECL_CONTEXT (ns1), ns2); 3688 return nsr; 3689 } 3690 3691 /* Wrapper for namespace_ancestor_1. */ 3692 3693 static tree 3694 namespace_ancestor (tree ns1, tree ns2) 3695 { 3696 tree nsr; 3697 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 3698 nsr = namespace_ancestor_1 (ns1, ns2); 3699 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 3700 return nsr; 3701 } 3702 3703 /* Process a namespace-alias declaration. */ 3704 3705 void 3706 do_namespace_alias (tree alias, tree name_space) 3707 { 3708 if (name_space == error_mark_node) 3709 return; 3710 3711 gcc_assert (TREE_CODE (name_space) == NAMESPACE_DECL); 3712 3713 name_space = ORIGINAL_NAMESPACE (name_space); 3714 3715 /* Build the alias. */ 3716 alias = build_lang_decl (NAMESPACE_DECL, alias, void_type_node); 3717 DECL_NAMESPACE_ALIAS (alias) = name_space; 3718 DECL_EXTERNAL (alias) = 1; 3719 DECL_CONTEXT (alias) = FROB_CONTEXT (current_scope ()); 3720 pushdecl (alias); 3721 3722 /* Emit debug info for namespace alias. */ 3723 if (!building_stmt_list_p ()) 3724 (*debug_hooks->global_decl) (alias); 3725 } 3726 3727 /* Like pushdecl, only it places X in the current namespace, 3728 if appropriate. */ 3729 3730 tree 3731 pushdecl_namespace_level (tree x, bool is_friend) 3732 { 3733 cp_binding_level *b = current_binding_level; 3734 tree t; 3735 3736 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 3737 t = pushdecl_with_scope (x, NAMESPACE_LEVEL (current_namespace), is_friend); 3738 3739 /* Now, the type_shadowed stack may screw us. Munge it so it does 3740 what we want. */ 3741 if (TREE_CODE (t) == TYPE_DECL) 3742 { 3743 tree name = DECL_NAME (t); 3744 tree newval; 3745 tree *ptr = (tree *)0; 3746 for (; !global_scope_p (b); b = b->level_chain) 3747 { 3748 tree shadowed = b->type_shadowed; 3749 for (; shadowed; shadowed = TREE_CHAIN (shadowed)) 3750 if (TREE_PURPOSE (shadowed) == name) 3751 { 3752 ptr = &TREE_VALUE (shadowed); 3753 /* Can't break out of the loop here because sometimes 3754 a binding level will have duplicate bindings for 3755 PT names. It's gross, but I haven't time to fix it. */ 3756 } 3757 } 3758 newval = TREE_TYPE (t); 3759 if (ptr == (tree *)0) 3760 { 3761 /* @@ This shouldn't be needed. My test case "zstring.cc" trips 3762 up here if this is changed to an assertion. --KR */ 3763 SET_IDENTIFIER_TYPE_VALUE (name, t); 3764 } 3765 else 3766 { 3767 *ptr = newval; 3768 } 3769 } 3770 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 3771 return t; 3772 } 3773 3774 /* Insert USED into the using list of USER. Set INDIRECT_flag if this 3775 directive is not directly from the source. Also find the common 3776 ancestor and let our users know about the new namespace */ 3777 3778 static void 3779 add_using_namespace_1 (tree user, tree used, bool indirect) 3780 { 3781 tree t; 3782 /* Using oneself is a no-op. */ 3783 if (user == used) 3784 return; 3785 gcc_assert (TREE_CODE (user) == NAMESPACE_DECL); 3786 gcc_assert (TREE_CODE (used) == NAMESPACE_DECL); 3787 /* Check if we already have this. */ 3788 t = purpose_member (used, DECL_NAMESPACE_USING (user)); 3789 if (t != NULL_TREE) 3790 { 3791 if (!indirect) 3792 /* Promote to direct usage. */ 3793 TREE_INDIRECT_USING (t) = 0; 3794 return; 3795 } 3796 3797 /* Add used to the user's using list. */ 3798 DECL_NAMESPACE_USING (user) 3799 = tree_cons (used, namespace_ancestor (user, used), 3800 DECL_NAMESPACE_USING (user)); 3801 3802 TREE_INDIRECT_USING (DECL_NAMESPACE_USING (user)) = indirect; 3803 3804 /* Add user to the used's users list. */ 3805 DECL_NAMESPACE_USERS (used) 3806 = tree_cons (user, 0, DECL_NAMESPACE_USERS (used)); 3807 3808 /* Recursively add all namespaces used. */ 3809 for (t = DECL_NAMESPACE_USING (used); t; t = TREE_CHAIN (t)) 3810 /* indirect usage */ 3811 add_using_namespace_1 (user, TREE_PURPOSE (t), 1); 3812 3813 /* Tell everyone using us about the new used namespaces. */ 3814 for (t = DECL_NAMESPACE_USERS (user); t; t = TREE_CHAIN (t)) 3815 add_using_namespace_1 (TREE_PURPOSE (t), used, 1); 3816 } 3817 3818 /* Wrapper for add_using_namespace_1. */ 3819 3820 static void 3821 add_using_namespace (tree user, tree used, bool indirect) 3822 { 3823 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 3824 add_using_namespace_1 (user, used, indirect); 3825 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 3826 } 3827 3828 /* Process a using-declaration not appearing in class or local scope. */ 3829 3830 void 3831 do_toplevel_using_decl (tree decl, tree scope, tree name) 3832 { 3833 tree oldval, oldtype, newval, newtype; 3834 tree orig_decl = decl; 3835 cxx_binding *binding; 3836 3837 decl = validate_nonmember_using_decl (decl, scope, name); 3838 if (decl == NULL_TREE) 3839 return; 3840 3841 binding = binding_for_name (NAMESPACE_LEVEL (current_namespace), name); 3842 3843 oldval = binding->value; 3844 oldtype = binding->type; 3845 3846 do_nonmember_using_decl (scope, name, oldval, oldtype, &newval, &newtype); 3847 3848 /* Emit debug info. */ 3849 if (!processing_template_decl) 3850 cp_emit_debug_info_for_using (orig_decl, current_namespace); 3851 3852 /* Copy declarations found. */ 3853 if (newval) 3854 binding->value = newval; 3855 if (newtype) 3856 binding->type = newtype; 3857 } 3858 3859 /* Process a using-directive. */ 3860 3861 void 3862 do_using_directive (tree name_space) 3863 { 3864 tree context = NULL_TREE; 3865 3866 if (name_space == error_mark_node) 3867 return; 3868 3869 gcc_assert (TREE_CODE (name_space) == NAMESPACE_DECL); 3870 3871 if (building_stmt_list_p ()) 3872 add_stmt (build_stmt (input_location, USING_STMT, name_space)); 3873 name_space = ORIGINAL_NAMESPACE (name_space); 3874 3875 if (!toplevel_bindings_p ()) 3876 { 3877 push_using_directive (name_space); 3878 } 3879 else 3880 { 3881 /* direct usage */ 3882 add_using_namespace (current_namespace, name_space, 0); 3883 if (current_namespace != global_namespace) 3884 context = current_namespace; 3885 3886 /* Emit debugging info. */ 3887 if (!processing_template_decl) 3888 (*debug_hooks->imported_module_or_decl) (name_space, NULL_TREE, 3889 context, false); 3890 } 3891 } 3892 3893 /* Deal with a using-directive seen by the parser. Currently we only 3894 handle attributes here, since they cannot appear inside a template. */ 3895 3896 void 3897 parse_using_directive (tree name_space, tree attribs) 3898 { 3899 tree a; 3900 3901 do_using_directive (name_space); 3902 3903 for (a = attribs; a; a = TREE_CHAIN (a)) 3904 { 3905 tree name = TREE_PURPOSE (a); 3906 if (is_attribute_p ("strong", name)) 3907 { 3908 if (!toplevel_bindings_p ()) 3909 error ("strong using only meaningful at namespace scope"); 3910 else if (name_space != error_mark_node) 3911 { 3912 if (!is_ancestor (current_namespace, name_space)) 3913 error ("current namespace %qD does not enclose strongly used namespace %qD", 3914 current_namespace, name_space); 3915 DECL_NAMESPACE_ASSOCIATIONS (name_space) 3916 = tree_cons (current_namespace, 0, 3917 DECL_NAMESPACE_ASSOCIATIONS (name_space)); 3918 } 3919 } 3920 else 3921 warning (OPT_Wattributes, "%qD attribute directive ignored", name); 3922 } 3923 } 3924 3925 /* Like pushdecl, only it places X in the global scope if appropriate. 3926 Calls cp_finish_decl to register the variable, initializing it with 3927 *INIT, if INIT is non-NULL. */ 3928 3929 static tree 3930 pushdecl_top_level_1 (tree x, tree *init, bool is_friend) 3931 { 3932 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 3933 push_to_top_level (); 3934 x = pushdecl_namespace_level (x, is_friend); 3935 if (init) 3936 cp_finish_decl (x, *init, false, NULL_TREE, 0); 3937 pop_from_top_level (); 3938 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 3939 return x; 3940 } 3941 3942 /* Like pushdecl, only it places X in the global scope if appropriate. */ 3943 3944 tree 3945 pushdecl_top_level (tree x) 3946 { 3947 return pushdecl_top_level_1 (x, NULL, false); 3948 } 3949 3950 /* Like pushdecl_top_level, but adding the IS_FRIEND parameter. */ 3951 3952 tree 3953 pushdecl_top_level_maybe_friend (tree x, bool is_friend) 3954 { 3955 return pushdecl_top_level_1 (x, NULL, is_friend); 3956 } 3957 3958 /* Like pushdecl, only it places X in the global scope if 3959 appropriate. Calls cp_finish_decl to register the variable, 3960 initializing it with INIT. */ 3961 3962 tree 3963 pushdecl_top_level_and_finish (tree x, tree init) 3964 { 3965 return pushdecl_top_level_1 (x, &init, false); 3966 } 3967 3968 /* Combines two sets of overloaded functions into an OVERLOAD chain, removing 3969 duplicates. The first list becomes the tail of the result. 3970 3971 The algorithm is O(n^2). We could get this down to O(n log n) by 3972 doing a sort on the addresses of the functions, if that becomes 3973 necessary. */ 3974 3975 static tree 3976 merge_functions (tree s1, tree s2) 3977 { 3978 for (; s2; s2 = OVL_NEXT (s2)) 3979 { 3980 tree fn2 = OVL_CURRENT (s2); 3981 tree fns1; 3982 3983 for (fns1 = s1; fns1; fns1 = OVL_NEXT (fns1)) 3984 { 3985 tree fn1 = OVL_CURRENT (fns1); 3986 3987 /* If the function from S2 is already in S1, there is no 3988 need to add it again. For `extern "C"' functions, we 3989 might have two FUNCTION_DECLs for the same function, in 3990 different namespaces, but let's leave them in in case 3991 they have different default arguments. */ 3992 if (fn1 == fn2) 3993 break; 3994 } 3995 3996 /* If we exhausted all of the functions in S1, FN2 is new. */ 3997 if (!fns1) 3998 s1 = build_overload (fn2, s1); 3999 } 4000 return s1; 4001 } 4002 4003 /* Returns TRUE iff OLD and NEW are the same entity. 4004 4005 3 [basic]/3: An entity is a value, object, reference, function, 4006 enumerator, type, class member, template, template specialization, 4007 namespace, parameter pack, or this. 4008 4009 7.3.4 [namespace.udir]/4: If name lookup finds a declaration for a name 4010 in two different namespaces, and the declarations do not declare the 4011 same entity and do not declare functions, the use of the name is 4012 ill-formed. */ 4013 4014 static bool 4015 same_entity_p (tree one, tree two) 4016 { 4017 if (one == two) 4018 return true; 4019 if (!one || !two) 4020 return false; 4021 if (TREE_CODE (one) == TYPE_DECL 4022 && TREE_CODE (two) == TYPE_DECL 4023 && same_type_p (TREE_TYPE (one), TREE_TYPE (two))) 4024 return true; 4025 return false; 4026 } 4027 4028 /* This should return an error not all definitions define functions. 4029 It is not an error if we find two functions with exactly the 4030 same signature, only if these are selected in overload resolution. 4031 old is the current set of bindings, new_binding the freshly-found binding. 4032 XXX Do we want to give *all* candidates in case of ambiguity? 4033 XXX In what way should I treat extern declarations? 4034 XXX I don't want to repeat the entire duplicate_decls here */ 4035 4036 static void 4037 ambiguous_decl (struct scope_binding *old, cxx_binding *new_binding, int flags) 4038 { 4039 tree val, type; 4040 gcc_assert (old != NULL); 4041 4042 /* Copy the type. */ 4043 type = new_binding->type; 4044 if (LOOKUP_NAMESPACES_ONLY (flags) 4045 || (type && hidden_name_p (type) && !(flags & LOOKUP_HIDDEN))) 4046 type = NULL_TREE; 4047 4048 /* Copy the value. */ 4049 val = new_binding->value; 4050 if (val) 4051 { 4052 if (hidden_name_p (val) && !(flags & LOOKUP_HIDDEN)) 4053 val = NULL_TREE; 4054 else 4055 switch (TREE_CODE (val)) 4056 { 4057 case TEMPLATE_DECL: 4058 /* If we expect types or namespaces, and not templates, 4059 or this is not a template class. */ 4060 if ((LOOKUP_QUALIFIERS_ONLY (flags) 4061 && !DECL_CLASS_TEMPLATE_P (val))) 4062 val = NULL_TREE; 4063 break; 4064 case TYPE_DECL: 4065 if (LOOKUP_NAMESPACES_ONLY (flags) 4066 || (type && (flags & LOOKUP_PREFER_TYPES))) 4067 val = NULL_TREE; 4068 break; 4069 case NAMESPACE_DECL: 4070 if (LOOKUP_TYPES_ONLY (flags)) 4071 val = NULL_TREE; 4072 break; 4073 case FUNCTION_DECL: 4074 /* Ignore built-in functions that are still anticipated. */ 4075 if (LOOKUP_QUALIFIERS_ONLY (flags)) 4076 val = NULL_TREE; 4077 break; 4078 default: 4079 if (LOOKUP_QUALIFIERS_ONLY (flags)) 4080 val = NULL_TREE; 4081 } 4082 } 4083 4084 /* If val is hidden, shift down any class or enumeration name. */ 4085 if (!val) 4086 { 4087 val = type; 4088 type = NULL_TREE; 4089 } 4090 4091 if (!old->value) 4092 old->value = val; 4093 else if (val && !same_entity_p (val, old->value)) 4094 { 4095 if (is_overloaded_fn (old->value) && is_overloaded_fn (val)) 4096 old->value = merge_functions (old->value, val); 4097 else 4098 { 4099 old->value = tree_cons (NULL_TREE, old->value, 4100 build_tree_list (NULL_TREE, val)); 4101 TREE_TYPE (old->value) = error_mark_node; 4102 } 4103 } 4104 4105 if (!old->type) 4106 old->type = type; 4107 else if (type && old->type != type) 4108 { 4109 old->type = tree_cons (NULL_TREE, old->type, 4110 build_tree_list (NULL_TREE, type)); 4111 TREE_TYPE (old->type) = error_mark_node; 4112 } 4113 } 4114 4115 /* Return the declarations that are members of the namespace NS. */ 4116 4117 tree 4118 cp_namespace_decls (tree ns) 4119 { 4120 return NAMESPACE_LEVEL (ns)->names; 4121 } 4122 4123 /* Combine prefer_type and namespaces_only into flags. */ 4124 4125 static int 4126 lookup_flags (int prefer_type, int namespaces_only) 4127 { 4128 if (namespaces_only) 4129 return LOOKUP_PREFER_NAMESPACES; 4130 if (prefer_type > 1) 4131 return LOOKUP_PREFER_TYPES; 4132 if (prefer_type > 0) 4133 return LOOKUP_PREFER_BOTH; 4134 return 0; 4135 } 4136 4137 /* Given a lookup that returned VAL, use FLAGS to decide if we want to 4138 ignore it or not. Subroutine of lookup_name_real and 4139 lookup_type_scope. */ 4140 4141 static bool 4142 qualify_lookup (tree val, int flags) 4143 { 4144 if (val == NULL_TREE) 4145 return false; 4146 if ((flags & LOOKUP_PREFER_NAMESPACES) && TREE_CODE (val) == NAMESPACE_DECL) 4147 return true; 4148 if (flags & LOOKUP_PREFER_TYPES) 4149 { 4150 tree target_val = strip_using_decl (val); 4151 if (TREE_CODE (target_val) == TYPE_DECL 4152 || TREE_CODE (target_val) == TEMPLATE_DECL) 4153 return true; 4154 } 4155 if (flags & (LOOKUP_PREFER_NAMESPACES | LOOKUP_PREFER_TYPES)) 4156 return false; 4157 /* Look through lambda things that we shouldn't be able to see. */ 4158 if (is_lambda_ignored_entity (val)) 4159 return false; 4160 return true; 4161 } 4162 4163 /* Given a lookup that returned VAL, decide if we want to ignore it or 4164 not based on DECL_ANTICIPATED. */ 4165 4166 bool 4167 hidden_name_p (tree val) 4168 { 4169 if (DECL_P (val) 4170 && DECL_LANG_SPECIFIC (val) 4171 && DECL_ANTICIPATED (val)) 4172 return true; 4173 return false; 4174 } 4175 4176 /* Remove any hidden friend functions from a possibly overloaded set 4177 of functions. */ 4178 4179 tree 4180 remove_hidden_names (tree fns) 4181 { 4182 if (!fns) 4183 return fns; 4184 4185 if (TREE_CODE (fns) == FUNCTION_DECL && hidden_name_p (fns)) 4186 fns = NULL_TREE; 4187 else if (TREE_CODE (fns) == OVERLOAD) 4188 { 4189 tree o; 4190 4191 for (o = fns; o; o = OVL_NEXT (o)) 4192 if (hidden_name_p (OVL_CURRENT (o))) 4193 break; 4194 if (o) 4195 { 4196 tree n = NULL_TREE; 4197 4198 for (o = fns; o; o = OVL_NEXT (o)) 4199 if (!hidden_name_p (OVL_CURRENT (o))) 4200 n = build_overload (OVL_CURRENT (o), n); 4201 fns = n; 4202 } 4203 } 4204 4205 return fns; 4206 } 4207 4208 /* Suggest alternatives for NAME, an IDENTIFIER_NODE for which name 4209 lookup failed. Search through all available namespaces and print out 4210 possible candidates. */ 4211 4212 void 4213 suggest_alternatives_for (location_t location, tree name) 4214 { 4215 VEC(tree,heap) *candidates = NULL; 4216 VEC(tree,heap) *namespaces_to_search = NULL; 4217 int max_to_search = PARAM_VALUE (CXX_MAX_NAMESPACES_FOR_DIAGNOSTIC_HELP); 4218 int n_searched = 0; 4219 tree t; 4220 unsigned ix; 4221 4222 VEC_safe_push (tree, heap, namespaces_to_search, global_namespace); 4223 4224 while (!VEC_empty (tree, namespaces_to_search) 4225 && n_searched < max_to_search) 4226 { 4227 tree scope = VEC_pop (tree, namespaces_to_search); 4228 struct scope_binding binding = EMPTY_SCOPE_BINDING; 4229 cp_binding_level *level = NAMESPACE_LEVEL (scope); 4230 4231 /* Look in this namespace. */ 4232 qualified_lookup_using_namespace (name, scope, &binding, 0); 4233 4234 n_searched++; 4235 4236 if (binding.value) 4237 VEC_safe_push (tree, heap, candidates, binding.value); 4238 4239 /* Add child namespaces. */ 4240 for (t = level->namespaces; t; t = DECL_CHAIN (t)) 4241 VEC_safe_push (tree, heap, namespaces_to_search, t); 4242 } 4243 4244 /* If we stopped before we could examine all namespaces, inform the 4245 user. Do this even if we don't have any candidates, since there 4246 might be more candidates further down that we weren't able to 4247 find. */ 4248 if (n_searched >= max_to_search 4249 && !VEC_empty (tree, namespaces_to_search)) 4250 inform (location, 4251 "maximum limit of %d namespaces searched for %qE", 4252 max_to_search, name); 4253 4254 VEC_free (tree, heap, namespaces_to_search); 4255 4256 /* Nothing useful to report. */ 4257 if (VEC_empty (tree, candidates)) 4258 return; 4259 4260 inform_n (location, VEC_length (tree, candidates), 4261 "suggested alternative:", 4262 "suggested alternatives:"); 4263 4264 FOR_EACH_VEC_ELT (tree, candidates, ix, t) 4265 inform (location_of (t), " %qE", t); 4266 4267 VEC_free (tree, heap, candidates); 4268 } 4269 4270 /* Unscoped lookup of a global: iterate over current namespaces, 4271 considering using-directives. */ 4272 4273 static tree 4274 unqualified_namespace_lookup_1 (tree name, int flags) 4275 { 4276 tree initial = current_decl_namespace (); 4277 tree scope = initial; 4278 tree siter; 4279 cp_binding_level *level; 4280 tree val = NULL_TREE; 4281 4282 for (; !val; scope = CP_DECL_CONTEXT (scope)) 4283 { 4284 struct scope_binding binding = EMPTY_SCOPE_BINDING; 4285 cxx_binding *b = 4286 cp_binding_level_find_binding_for_name (NAMESPACE_LEVEL (scope), name); 4287 4288 if (b) 4289 ambiguous_decl (&binding, b, flags); 4290 4291 /* Add all _DECLs seen through local using-directives. */ 4292 for (level = current_binding_level; 4293 level->kind != sk_namespace; 4294 level = level->level_chain) 4295 if (!lookup_using_namespace (name, &binding, level->using_directives, 4296 scope, flags)) 4297 /* Give up because of error. */ 4298 return error_mark_node; 4299 4300 /* Add all _DECLs seen through global using-directives. */ 4301 /* XXX local and global using lists should work equally. */ 4302 siter = initial; 4303 while (1) 4304 { 4305 if (!lookup_using_namespace (name, &binding, 4306 DECL_NAMESPACE_USING (siter), 4307 scope, flags)) 4308 /* Give up because of error. */ 4309 return error_mark_node; 4310 if (siter == scope) break; 4311 siter = CP_DECL_CONTEXT (siter); 4312 } 4313 4314 val = binding.value; 4315 if (scope == global_namespace) 4316 break; 4317 } 4318 return val; 4319 } 4320 4321 /* Wrapper for unqualified_namespace_lookup_1. */ 4322 4323 static tree 4324 unqualified_namespace_lookup (tree name, int flags) 4325 { 4326 tree ret; 4327 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 4328 ret = unqualified_namespace_lookup_1 (name, flags); 4329 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 4330 return ret; 4331 } 4332 4333 /* Look up NAME (an IDENTIFIER_NODE) in SCOPE (either a NAMESPACE_DECL 4334 or a class TYPE). If IS_TYPE_P is TRUE, then ignore non-type 4335 bindings. 4336 4337 Returns a DECL (or OVERLOAD, or BASELINK) representing the 4338 declaration found. If no suitable declaration can be found, 4339 ERROR_MARK_NODE is returned. If COMPLAIN is true and SCOPE is 4340 neither a class-type nor a namespace a diagnostic is issued. */ 4341 4342 tree 4343 lookup_qualified_name (tree scope, tree name, bool is_type_p, bool complain) 4344 { 4345 int flags = 0; 4346 tree t = NULL_TREE; 4347 4348 if (TREE_CODE (scope) == NAMESPACE_DECL) 4349 { 4350 struct scope_binding binding = EMPTY_SCOPE_BINDING; 4351 4352 flags |= LOOKUP_COMPLAIN; 4353 if (is_type_p) 4354 flags |= LOOKUP_PREFER_TYPES; 4355 if (qualified_lookup_using_namespace (name, scope, &binding, flags)) 4356 t = binding.value; 4357 } 4358 else if (cxx_dialect != cxx98 && TREE_CODE (scope) == ENUMERAL_TYPE) 4359 t = lookup_enumerator (scope, name); 4360 else if (is_class_type (scope, complain)) 4361 t = lookup_member (scope, name, 2, is_type_p, tf_warning_or_error); 4362 4363 if (!t) 4364 return error_mark_node; 4365 return t; 4366 } 4367 4368 /* Subroutine of unqualified_namespace_lookup: 4369 Add the bindings of NAME in used namespaces to VAL. 4370 We are currently looking for names in namespace SCOPE, so we 4371 look through USINGS for using-directives of namespaces 4372 which have SCOPE as a common ancestor with the current scope. 4373 Returns false on errors. */ 4374 4375 static bool 4376 lookup_using_namespace (tree name, struct scope_binding *val, 4377 tree usings, tree scope, int flags) 4378 { 4379 tree iter; 4380 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 4381 /* Iterate over all used namespaces in current, searching for using 4382 directives of scope. */ 4383 for (iter = usings; iter; iter = TREE_CHAIN (iter)) 4384 if (TREE_VALUE (iter) == scope) 4385 { 4386 tree used = ORIGINAL_NAMESPACE (TREE_PURPOSE (iter)); 4387 cxx_binding *val1 = 4388 cp_binding_level_find_binding_for_name (NAMESPACE_LEVEL (used), name); 4389 /* Resolve ambiguities. */ 4390 if (val1) 4391 ambiguous_decl (val, val1, flags); 4392 } 4393 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 4394 return val->value != error_mark_node; 4395 } 4396 4397 /* Returns true iff VEC contains TARGET. */ 4398 4399 static bool 4400 tree_vec_contains (VEC(tree,gc)* vec, tree target) 4401 { 4402 unsigned int i; 4403 tree elt; 4404 FOR_EACH_VEC_ELT (tree,vec,i,elt) 4405 if (elt == target) 4406 return true; 4407 return false; 4408 } 4409 4410 /* [namespace.qual] 4411 Accepts the NAME to lookup and its qualifying SCOPE. 4412 Returns the name/type pair found into the cxx_binding *RESULT, 4413 or false on error. */ 4414 4415 static bool 4416 qualified_lookup_using_namespace (tree name, tree scope, 4417 struct scope_binding *result, int flags) 4418 { 4419 /* Maintain a list of namespaces visited... */ 4420 VEC(tree,gc) *seen = NULL; 4421 VEC(tree,gc) *seen_inline = NULL; 4422 /* ... and a list of namespace yet to see. */ 4423 VEC(tree,gc) *todo = NULL; 4424 VEC(tree,gc) *todo_maybe = NULL; 4425 VEC(tree,gc) *todo_inline = NULL; 4426 tree usings; 4427 timevar_start (TV_NAME_LOOKUP); 4428 /* Look through namespace aliases. */ 4429 scope = ORIGINAL_NAMESPACE (scope); 4430 4431 /* Algorithm: Starting with SCOPE, walk through the set of used 4432 namespaces. For each used namespace, look through its inline 4433 namespace set for any bindings and usings. If no bindings are 4434 found, add any usings seen to the set of used namespaces. */ 4435 VEC_safe_push (tree, gc, todo, scope); 4436 4437 while (VEC_length (tree, todo)) 4438 { 4439 bool found_here; 4440 scope = VEC_pop (tree, todo); 4441 if (tree_vec_contains (seen, scope)) 4442 continue; 4443 VEC_safe_push (tree, gc, seen, scope); 4444 VEC_safe_push (tree, gc, todo_inline, scope); 4445 4446 found_here = false; 4447 while (VEC_length (tree, todo_inline)) 4448 { 4449 cxx_binding *binding; 4450 4451 scope = VEC_pop (tree, todo_inline); 4452 if (tree_vec_contains (seen_inline, scope)) 4453 continue; 4454 VEC_safe_push (tree, gc, seen_inline, scope); 4455 4456 binding = 4457 cp_binding_level_find_binding_for_name (NAMESPACE_LEVEL (scope), name); 4458 if (binding) 4459 { 4460 found_here = true; 4461 ambiguous_decl (result, binding, flags); 4462 } 4463 4464 for (usings = DECL_NAMESPACE_USING (scope); usings; 4465 usings = TREE_CHAIN (usings)) 4466 if (!TREE_INDIRECT_USING (usings)) 4467 { 4468 if (is_associated_namespace (scope, TREE_PURPOSE (usings))) 4469 VEC_safe_push (tree, gc, todo_inline, TREE_PURPOSE (usings)); 4470 else 4471 VEC_safe_push (tree, gc, todo_maybe, TREE_PURPOSE (usings)); 4472 } 4473 } 4474 4475 if (found_here) 4476 VEC_truncate (tree, todo_maybe, 0); 4477 else 4478 while (VEC_length (tree, todo_maybe)) 4479 VEC_safe_push (tree, gc, todo, VEC_pop (tree, todo_maybe)); 4480 } 4481 VEC_free (tree,gc,todo); 4482 VEC_free (tree,gc,todo_maybe); 4483 VEC_free (tree,gc,todo_inline); 4484 VEC_free (tree,gc,seen); 4485 VEC_free (tree,gc,seen_inline); 4486 timevar_stop (TV_NAME_LOOKUP); 4487 return result->value != error_mark_node; 4488 } 4489 4490 /* Subroutine of outer_binding. 4491 4492 Returns TRUE if BINDING is a binding to a template parameter of 4493 SCOPE. In that case SCOPE is the scope of a primary template 4494 parameter -- in the sense of G++, i.e, a template that has its own 4495 template header. 4496 4497 Returns FALSE otherwise. */ 4498 4499 static bool 4500 binding_to_template_parms_of_scope_p (cxx_binding *binding, 4501 cp_binding_level *scope) 4502 { 4503 tree binding_value; 4504 4505 if (!binding || !scope) 4506 return false; 4507 4508 binding_value = binding->value ? binding->value : binding->type; 4509 4510 return (scope 4511 && scope->this_entity 4512 && get_template_info (scope->this_entity) 4513 && PRIMARY_TEMPLATE_P (TI_TEMPLATE 4514 (get_template_info (scope->this_entity))) 4515 && parameter_of_template_p (binding_value, 4516 TI_TEMPLATE (get_template_info \ 4517 (scope->this_entity)))); 4518 } 4519 4520 /* Return the innermost non-namespace binding for NAME from a scope 4521 containing BINDING, or, if BINDING is NULL, the current scope. 4522 Please note that for a given template, the template parameters are 4523 considered to be in the scope containing the current scope. 4524 If CLASS_P is false, then class bindings are ignored. */ 4525 4526 cxx_binding * 4527 outer_binding (tree name, 4528 cxx_binding *binding, 4529 bool class_p) 4530 { 4531 cxx_binding *outer; 4532 cp_binding_level *scope; 4533 cp_binding_level *outer_scope; 4534 4535 if (binding) 4536 { 4537 scope = binding->scope->level_chain; 4538 outer = binding->previous; 4539 } 4540 else 4541 { 4542 scope = current_binding_level; 4543 outer = IDENTIFIER_BINDING (name); 4544 } 4545 outer_scope = outer ? outer->scope : NULL; 4546 4547 /* Because we create class bindings lazily, we might be missing a 4548 class binding for NAME. If there are any class binding levels 4549 between the LAST_BINDING_LEVEL and the scope in which OUTER was 4550 declared, we must lookup NAME in those class scopes. */ 4551 if (class_p) 4552 while (scope && scope != outer_scope && scope->kind != sk_namespace) 4553 { 4554 if (scope->kind == sk_class) 4555 { 4556 cxx_binding *class_binding; 4557 4558 class_binding = get_class_binding (name, scope); 4559 if (class_binding) 4560 { 4561 /* Thread this new class-scope binding onto the 4562 IDENTIFIER_BINDING list so that future lookups 4563 find it quickly. */ 4564 class_binding->previous = outer; 4565 if (binding) 4566 binding->previous = class_binding; 4567 else 4568 IDENTIFIER_BINDING (name) = class_binding; 4569 return class_binding; 4570 } 4571 } 4572 /* If we are in a member template, the template parms of the member 4573 template are considered to be inside the scope of the containing 4574 class, but within G++ the class bindings are all pushed between the 4575 template parms and the function body. So if the outer binding is 4576 a template parm for the current scope, return it now rather than 4577 look for a class binding. */ 4578 if (outer_scope && outer_scope->kind == sk_template_parms 4579 && binding_to_template_parms_of_scope_p (outer, scope)) 4580 return outer; 4581 4582 scope = scope->level_chain; 4583 } 4584 4585 return outer; 4586 } 4587 4588 /* Return the innermost block-scope or class-scope value binding for 4589 NAME, or NULL_TREE if there is no such binding. */ 4590 4591 tree 4592 innermost_non_namespace_value (tree name) 4593 { 4594 cxx_binding *binding; 4595 binding = outer_binding (name, /*binding=*/NULL, /*class_p=*/true); 4596 return binding ? binding->value : NULL_TREE; 4597 } 4598 4599 /* Look up NAME in the current binding level and its superiors in the 4600 namespace of variables, functions and typedefs. Return a ..._DECL 4601 node of some kind representing its definition if there is only one 4602 such declaration, or return a TREE_LIST with all the overloaded 4603 definitions if there are many, or return 0 if it is undefined. 4604 Hidden name, either friend declaration or built-in function, are 4605 not ignored. 4606 4607 If PREFER_TYPE is > 0, we prefer TYPE_DECLs or namespaces. 4608 If PREFER_TYPE is > 1, we reject non-type decls (e.g. namespaces). 4609 Otherwise we prefer non-TYPE_DECLs. 4610 4611 If NONCLASS is nonzero, bindings in class scopes are ignored. If 4612 BLOCK_P is false, bindings in block scopes are ignored. */ 4613 4614 static tree 4615 lookup_name_real_1 (tree name, int prefer_type, int nonclass, bool block_p, 4616 int namespaces_only, int flags) 4617 { 4618 cxx_binding *iter; 4619 tree val = NULL_TREE; 4620 4621 /* Conversion operators are handled specially because ordinary 4622 unqualified name lookup will not find template conversion 4623 operators. */ 4624 if (IDENTIFIER_TYPENAME_P (name)) 4625 { 4626 cp_binding_level *level; 4627 4628 for (level = current_binding_level; 4629 level && level->kind != sk_namespace; 4630 level = level->level_chain) 4631 { 4632 tree class_type; 4633 tree operators; 4634 4635 /* A conversion operator can only be declared in a class 4636 scope. */ 4637 if (level->kind != sk_class) 4638 continue; 4639 4640 /* Lookup the conversion operator in the class. */ 4641 class_type = level->this_entity; 4642 operators = lookup_fnfields (class_type, name, /*protect=*/0); 4643 if (operators) 4644 return operators; 4645 } 4646 4647 return NULL_TREE; 4648 } 4649 4650 flags |= lookup_flags (prefer_type, namespaces_only); 4651 4652 /* First, look in non-namespace scopes. */ 4653 4654 if (current_class_type == NULL_TREE) 4655 nonclass = 1; 4656 4657 if (block_p || !nonclass) 4658 for (iter = outer_binding (name, NULL, !nonclass); 4659 iter; 4660 iter = outer_binding (name, iter, !nonclass)) 4661 { 4662 tree binding; 4663 4664 /* Skip entities we don't want. */ 4665 if (LOCAL_BINDING_P (iter) ? !block_p : nonclass) 4666 continue; 4667 4668 /* If this is the kind of thing we're looking for, we're done. */ 4669 if (qualify_lookup (iter->value, flags)) 4670 binding = iter->value; 4671 else if ((flags & LOOKUP_PREFER_TYPES) 4672 && qualify_lookup (iter->type, flags)) 4673 binding = iter->type; 4674 else 4675 binding = NULL_TREE; 4676 4677 if (binding) 4678 { 4679 if (hidden_name_p (binding)) 4680 { 4681 /* A non namespace-scope binding can only be hidden in the 4682 presence of a local class, due to friend declarations. 4683 4684 In particular, consider: 4685 4686 struct C; 4687 void f() { 4688 struct A { 4689 friend struct B; 4690 friend struct C; 4691 void g() { 4692 B* b; // error: B is hidden 4693 C* c; // OK, finds ::C 4694 } 4695 }; 4696 B *b; // error: B is hidden 4697 C *c; // OK, finds ::C 4698 struct B {}; 4699 B *bb; // OK 4700 } 4701 4702 The standard says that "B" is a local class in "f" 4703 (but not nested within "A") -- but that name lookup 4704 for "B" does not find this declaration until it is 4705 declared directly with "f". 4706 4707 In particular: 4708 4709 [class.friend] 4710 4711 If a friend declaration appears in a local class and 4712 the name specified is an unqualified name, a prior 4713 declaration is looked up without considering scopes 4714 that are outside the innermost enclosing non-class 4715 scope. For a friend function declaration, if there is 4716 no prior declaration, the program is ill-formed. For a 4717 friend class declaration, if there is no prior 4718 declaration, the class that is specified belongs to the 4719 innermost enclosing non-class scope, but if it is 4720 subsequently referenced, its name is not found by name 4721 lookup until a matching declaration is provided in the 4722 innermost enclosing nonclass scope. 4723 4724 So just keep looking for a non-hidden binding. 4725 */ 4726 gcc_assert (TREE_CODE (binding) == TYPE_DECL); 4727 continue; 4728 } 4729 val = binding; 4730 break; 4731 } 4732 } 4733 4734 /* Now lookup in namespace scopes. */ 4735 if (!val) 4736 val = unqualified_namespace_lookup (name, flags); 4737 4738 /* If we have a single function from a using decl, pull it out. */ 4739 if (val && TREE_CODE (val) == OVERLOAD && !really_overloaded_fn (val)) 4740 val = OVL_FUNCTION (val); 4741 4742 return val; 4743 } 4744 4745 /* Wrapper for lookup_name_real_1. */ 4746 4747 tree 4748 lookup_name_real (tree name, int prefer_type, int nonclass, bool block_p, 4749 int namespaces_only, int flags) 4750 { 4751 tree ret; 4752 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 4753 ret = lookup_name_real_1 (name, prefer_type, nonclass, block_p, 4754 namespaces_only, flags); 4755 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 4756 return ret; 4757 } 4758 4759 tree 4760 lookup_name_nonclass (tree name) 4761 { 4762 return lookup_name_real (name, 0, 1, /*block_p=*/true, 0, LOOKUP_COMPLAIN); 4763 } 4764 4765 tree 4766 lookup_function_nonclass (tree name, VEC(tree,gc) *args, bool block_p) 4767 { 4768 return 4769 lookup_arg_dependent (name, 4770 lookup_name_real (name, 0, 1, block_p, 0, 4771 LOOKUP_COMPLAIN), 4772 args, false); 4773 } 4774 4775 tree 4776 lookup_name (tree name) 4777 { 4778 return lookup_name_real (name, 0, 0, /*block_p=*/true, 0, LOOKUP_COMPLAIN); 4779 } 4780 4781 tree 4782 lookup_name_prefer_type (tree name, int prefer_type) 4783 { 4784 return lookup_name_real (name, prefer_type, 0, /*block_p=*/true, 4785 0, LOOKUP_COMPLAIN); 4786 } 4787 4788 /* Look up NAME for type used in elaborated name specifier in 4789 the scopes given by SCOPE. SCOPE can be either TS_CURRENT or 4790 TS_WITHIN_ENCLOSING_NON_CLASS. Although not implied by the 4791 name, more scopes are checked if cleanup or template parameter 4792 scope is encountered. 4793 4794 Unlike lookup_name_real, we make sure that NAME is actually 4795 declared in the desired scope, not from inheritance, nor using 4796 directive. For using declaration, there is DR138 still waiting 4797 to be resolved. Hidden name coming from an earlier friend 4798 declaration is also returned. 4799 4800 A TYPE_DECL best matching the NAME is returned. Catching error 4801 and issuing diagnostics are caller's responsibility. */ 4802 4803 static tree 4804 lookup_type_scope_1 (tree name, tag_scope scope) 4805 { 4806 cxx_binding *iter = NULL; 4807 tree val = NULL_TREE; 4808 4809 /* Look in non-namespace scope first. */ 4810 if (current_binding_level->kind != sk_namespace) 4811 iter = outer_binding (name, NULL, /*class_p=*/ true); 4812 for (; iter; iter = outer_binding (name, iter, /*class_p=*/ true)) 4813 { 4814 /* Check if this is the kind of thing we're looking for. 4815 If SCOPE is TS_CURRENT, also make sure it doesn't come from 4816 base class. For ITER->VALUE, we can simply use 4817 INHERITED_VALUE_BINDING_P. For ITER->TYPE, we have to use 4818 our own check. 4819 4820 We check ITER->TYPE before ITER->VALUE in order to handle 4821 typedef struct C {} C; 4822 correctly. */ 4823 4824 if (qualify_lookup (iter->type, LOOKUP_PREFER_TYPES) 4825 && (scope != ts_current 4826 || LOCAL_BINDING_P (iter) 4827 || DECL_CONTEXT (iter->type) == iter->scope->this_entity)) 4828 val = iter->type; 4829 else if ((scope != ts_current 4830 || !INHERITED_VALUE_BINDING_P (iter)) 4831 && qualify_lookup (iter->value, LOOKUP_PREFER_TYPES)) 4832 val = iter->value; 4833 4834 if (val) 4835 break; 4836 } 4837 4838 /* Look in namespace scope. */ 4839 if (!val) 4840 { 4841 iter = cp_binding_level_find_binding_for_name 4842 (NAMESPACE_LEVEL (current_decl_namespace ()), name); 4843 4844 if (iter) 4845 { 4846 /* If this is the kind of thing we're looking for, we're done. */ 4847 if (qualify_lookup (iter->type, LOOKUP_PREFER_TYPES)) 4848 val = iter->type; 4849 else if (qualify_lookup (iter->value, LOOKUP_PREFER_TYPES)) 4850 val = iter->value; 4851 } 4852 4853 } 4854 4855 /* Type found, check if it is in the allowed scopes, ignoring cleanup 4856 and template parameter scopes. */ 4857 if (val) 4858 { 4859 cp_binding_level *b = current_binding_level; 4860 while (b) 4861 { 4862 if (iter->scope == b) 4863 return val; 4864 4865 if (b->kind == sk_cleanup || b->kind == sk_template_parms 4866 || b->kind == sk_function_parms) 4867 b = b->level_chain; 4868 else if (b->kind == sk_class 4869 && scope == ts_within_enclosing_non_class) 4870 b = b->level_chain; 4871 else 4872 break; 4873 } 4874 } 4875 4876 return NULL_TREE; 4877 } 4878 4879 /* Wrapper for lookup_type_scope_1. */ 4880 4881 tree 4882 lookup_type_scope (tree name, tag_scope scope) 4883 { 4884 tree ret; 4885 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 4886 ret = lookup_type_scope_1 (name, scope); 4887 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 4888 return ret; 4889 } 4890 4891 4892 /* Similar to `lookup_name' but look only in the innermost non-class 4893 binding level. */ 4894 4895 static tree 4896 lookup_name_innermost_nonclass_level_1 (tree name) 4897 { 4898 cp_binding_level *b; 4899 tree t = NULL_TREE; 4900 4901 b = innermost_nonclass_level (); 4902 4903 if (b->kind == sk_namespace) 4904 { 4905 t = IDENTIFIER_NAMESPACE_VALUE (name); 4906 4907 /* extern "C" function() */ 4908 if (t != NULL_TREE && TREE_CODE (t) == TREE_LIST) 4909 t = TREE_VALUE (t); 4910 } 4911 else if (IDENTIFIER_BINDING (name) 4912 && LOCAL_BINDING_P (IDENTIFIER_BINDING (name))) 4913 { 4914 cxx_binding *binding; 4915 binding = IDENTIFIER_BINDING (name); 4916 while (1) 4917 { 4918 if (binding->scope == b 4919 && !(TREE_CODE (binding->value) == VAR_DECL 4920 && DECL_DEAD_FOR_LOCAL (binding->value))) 4921 return binding->value; 4922 4923 if (b->kind == sk_cleanup) 4924 b = b->level_chain; 4925 else 4926 break; 4927 } 4928 } 4929 4930 return t; 4931 } 4932 4933 /* Wrapper for lookup_name_innermost_nonclass_level_1. */ 4934 4935 tree 4936 lookup_name_innermost_nonclass_level (tree name) 4937 { 4938 tree ret; 4939 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 4940 ret = lookup_name_innermost_nonclass_level_1 (name); 4941 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 4942 return ret; 4943 } 4944 4945 4946 /* Returns true iff DECL is a block-scope extern declaration of a function 4947 or variable. */ 4948 4949 bool 4950 is_local_extern (tree decl) 4951 { 4952 cxx_binding *binding; 4953 4954 /* For functions, this is easy. */ 4955 if (TREE_CODE (decl) == FUNCTION_DECL) 4956 return DECL_LOCAL_FUNCTION_P (decl); 4957 4958 if (TREE_CODE (decl) != VAR_DECL) 4959 return false; 4960 if (!current_function_decl) 4961 return false; 4962 4963 /* For variables, this is not easy. We need to look at the binding stack 4964 for the identifier to see whether the decl we have is a local. */ 4965 for (binding = IDENTIFIER_BINDING (DECL_NAME (decl)); 4966 binding && binding->scope->kind != sk_namespace; 4967 binding = binding->previous) 4968 if (binding->value == decl) 4969 return LOCAL_BINDING_P (binding); 4970 4971 return false; 4972 } 4973 4974 /* Like lookup_name_innermost_nonclass_level, but for types. */ 4975 4976 static tree 4977 lookup_type_current_level (tree name) 4978 { 4979 tree t = NULL_TREE; 4980 4981 timevar_start (TV_NAME_LOOKUP); 4982 gcc_assert (current_binding_level->kind != sk_namespace); 4983 4984 if (REAL_IDENTIFIER_TYPE_VALUE (name) != NULL_TREE 4985 && REAL_IDENTIFIER_TYPE_VALUE (name) != global_type_node) 4986 { 4987 cp_binding_level *b = current_binding_level; 4988 while (1) 4989 { 4990 if (purpose_member (name, b->type_shadowed)) 4991 { 4992 t = REAL_IDENTIFIER_TYPE_VALUE (name); 4993 break; 4994 } 4995 if (b->kind == sk_cleanup) 4996 b = b->level_chain; 4997 else 4998 break; 4999 } 5000 } 5001 5002 timevar_stop (TV_NAME_LOOKUP); 5003 return t; 5004 } 5005 5006 /* [basic.lookup.koenig] */ 5007 /* A nonzero return value in the functions below indicates an error. */ 5008 5009 struct arg_lookup 5010 { 5011 tree name; 5012 VEC(tree,gc) *args; 5013 VEC(tree,gc) *namespaces; 5014 VEC(tree,gc) *classes; 5015 tree functions; 5016 struct pointer_set_t *fn_set; 5017 }; 5018 5019 static bool arg_assoc (struct arg_lookup*, tree); 5020 static bool arg_assoc_args (struct arg_lookup*, tree); 5021 static bool arg_assoc_args_vec (struct arg_lookup*, VEC(tree,gc) *); 5022 static bool arg_assoc_type (struct arg_lookup*, tree); 5023 static bool add_function (struct arg_lookup *, tree); 5024 static bool arg_assoc_namespace (struct arg_lookup *, tree); 5025 static bool arg_assoc_class_only (struct arg_lookup *, tree); 5026 static bool arg_assoc_bases (struct arg_lookup *, tree); 5027 static bool arg_assoc_class (struct arg_lookup *, tree); 5028 static bool arg_assoc_template_arg (struct arg_lookup*, tree); 5029 5030 /* Add a function to the lookup structure. 5031 Returns true on error. */ 5032 5033 static bool 5034 add_function (struct arg_lookup *k, tree fn) 5035 { 5036 if (!is_overloaded_fn (fn)) 5037 /* All names except those of (possibly overloaded) functions and 5038 function templates are ignored. */; 5039 else if (k->fn_set && pointer_set_insert (k->fn_set, fn)) 5040 /* It's already in the list. */; 5041 else if (!k->functions) 5042 k->functions = fn; 5043 else if (fn == k->functions) 5044 ; 5045 else 5046 { 5047 k->functions = build_overload (fn, k->functions); 5048 if (TREE_CODE (k->functions) == OVERLOAD) 5049 OVL_ARG_DEPENDENT (k->functions) = true; 5050 } 5051 5052 return false; 5053 } 5054 5055 /* Returns true iff CURRENT has declared itself to be an associated 5056 namespace of SCOPE via a strong using-directive (or transitive chain 5057 thereof). Both are namespaces. */ 5058 5059 bool 5060 is_associated_namespace (tree current, tree scope) 5061 { 5062 VEC(tree,gc) *seen = make_tree_vector (); 5063 VEC(tree,gc) *todo = make_tree_vector (); 5064 tree t; 5065 bool ret; 5066 5067 while (1) 5068 { 5069 if (scope == current) 5070 { 5071 ret = true; 5072 break; 5073 } 5074 VEC_safe_push (tree, gc, seen, scope); 5075 for (t = DECL_NAMESPACE_ASSOCIATIONS (scope); t; t = TREE_CHAIN (t)) 5076 if (!vec_member (TREE_PURPOSE (t), seen)) 5077 VEC_safe_push (tree, gc, todo, TREE_PURPOSE (t)); 5078 if (!VEC_empty (tree, todo)) 5079 { 5080 scope = VEC_last (tree, todo); 5081 VEC_pop (tree, todo); 5082 } 5083 else 5084 { 5085 ret = false; 5086 break; 5087 } 5088 } 5089 5090 release_tree_vector (seen); 5091 release_tree_vector (todo); 5092 5093 return ret; 5094 } 5095 5096 /* Add functions of a namespace to the lookup structure. 5097 Returns true on error. */ 5098 5099 static bool 5100 arg_assoc_namespace (struct arg_lookup *k, tree scope) 5101 { 5102 tree value; 5103 5104 if (vec_member (scope, k->namespaces)) 5105 return false; 5106 VEC_safe_push (tree, gc, k->namespaces, scope); 5107 5108 /* Check out our super-users. */ 5109 for (value = DECL_NAMESPACE_ASSOCIATIONS (scope); value; 5110 value = TREE_CHAIN (value)) 5111 if (arg_assoc_namespace (k, TREE_PURPOSE (value))) 5112 return true; 5113 5114 /* Also look down into inline namespaces. */ 5115 for (value = DECL_NAMESPACE_USING (scope); value; 5116 value = TREE_CHAIN (value)) 5117 if (is_associated_namespace (scope, TREE_PURPOSE (value))) 5118 if (arg_assoc_namespace (k, TREE_PURPOSE (value))) 5119 return true; 5120 5121 value = namespace_binding (k->name, scope); 5122 if (!value) 5123 return false; 5124 5125 for (; value; value = OVL_NEXT (value)) 5126 { 5127 /* We don't want to find arbitrary hidden functions via argument 5128 dependent lookup. We only want to find friends of associated 5129 classes, which we'll do via arg_assoc_class. */ 5130 if (hidden_name_p (OVL_CURRENT (value))) 5131 continue; 5132 5133 if (add_function (k, OVL_CURRENT (value))) 5134 return true; 5135 } 5136 5137 return false; 5138 } 5139 5140 /* Adds everything associated with a template argument to the lookup 5141 structure. Returns true on error. */ 5142 5143 static bool 5144 arg_assoc_template_arg (struct arg_lookup *k, tree arg) 5145 { 5146 /* [basic.lookup.koenig] 5147 5148 If T is a template-id, its associated namespaces and classes are 5149 ... the namespaces and classes associated with the types of the 5150 template arguments provided for template type parameters 5151 (excluding template template parameters); the namespaces in which 5152 any template template arguments are defined; and the classes in 5153 which any member templates used as template template arguments 5154 are defined. [Note: non-type template arguments do not 5155 contribute to the set of associated namespaces. ] */ 5156 5157 /* Consider first template template arguments. */ 5158 if (TREE_CODE (arg) == TEMPLATE_TEMPLATE_PARM 5159 || TREE_CODE (arg) == UNBOUND_CLASS_TEMPLATE) 5160 return false; 5161 else if (TREE_CODE (arg) == TEMPLATE_DECL) 5162 { 5163 tree ctx = CP_DECL_CONTEXT (arg); 5164 5165 /* It's not a member template. */ 5166 if (TREE_CODE (ctx) == NAMESPACE_DECL) 5167 return arg_assoc_namespace (k, ctx); 5168 /* Otherwise, it must be member template. */ 5169 else 5170 return arg_assoc_class_only (k, ctx); 5171 } 5172 /* It's an argument pack; handle it recursively. */ 5173 else if (ARGUMENT_PACK_P (arg)) 5174 { 5175 tree args = ARGUMENT_PACK_ARGS (arg); 5176 int i, len = TREE_VEC_LENGTH (args); 5177 for (i = 0; i < len; ++i) 5178 if (arg_assoc_template_arg (k, TREE_VEC_ELT (args, i))) 5179 return true; 5180 5181 return false; 5182 } 5183 /* It's not a template template argument, but it is a type template 5184 argument. */ 5185 else if (TYPE_P (arg)) 5186 return arg_assoc_type (k, arg); 5187 /* It's a non-type template argument. */ 5188 else 5189 return false; 5190 } 5191 5192 /* Adds the class and its friends to the lookup structure. 5193 Returns true on error. */ 5194 5195 static bool 5196 arg_assoc_class_only (struct arg_lookup *k, tree type) 5197 { 5198 tree list, friends, context; 5199 5200 /* Backend-built structures, such as __builtin_va_list, aren't 5201 affected by all this. */ 5202 if (!CLASS_TYPE_P (type)) 5203 return false; 5204 5205 context = decl_namespace_context (type); 5206 if (arg_assoc_namespace (k, context)) 5207 return true; 5208 5209 complete_type (type); 5210 5211 /* Process friends. */ 5212 for (list = DECL_FRIENDLIST (TYPE_MAIN_DECL (type)); list; 5213 list = TREE_CHAIN (list)) 5214 if (k->name == FRIEND_NAME (list)) 5215 for (friends = FRIEND_DECLS (list); friends; 5216 friends = TREE_CHAIN (friends)) 5217 { 5218 tree fn = TREE_VALUE (friends); 5219 5220 /* Only interested in global functions with potentially hidden 5221 (i.e. unqualified) declarations. */ 5222 if (CP_DECL_CONTEXT (fn) != context) 5223 continue; 5224 /* Template specializations are never found by name lookup. 5225 (Templates themselves can be found, but not template 5226 specializations.) */ 5227 if (TREE_CODE (fn) == FUNCTION_DECL && DECL_USE_TEMPLATE (fn)) 5228 continue; 5229 if (add_function (k, fn)) 5230 return true; 5231 } 5232 5233 return false; 5234 } 5235 5236 /* Adds the class and its bases to the lookup structure. 5237 Returns true on error. */ 5238 5239 static bool 5240 arg_assoc_bases (struct arg_lookup *k, tree type) 5241 { 5242 if (arg_assoc_class_only (k, type)) 5243 return true; 5244 5245 if (TYPE_BINFO (type)) 5246 { 5247 /* Process baseclasses. */ 5248 tree binfo, base_binfo; 5249 int i; 5250 5251 for (binfo = TYPE_BINFO (type), i = 0; 5252 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++) 5253 if (arg_assoc_bases (k, BINFO_TYPE (base_binfo))) 5254 return true; 5255 } 5256 5257 return false; 5258 } 5259 5260 /* Adds everything associated with a class argument type to the lookup 5261 structure. Returns true on error. 5262 5263 If T is a class type (including unions), its associated classes are: the 5264 class itself; the class of which it is a member, if any; and its direct 5265 and indirect base classes. Its associated namespaces are the namespaces 5266 of which its associated classes are members. Furthermore, if T is a 5267 class template specialization, its associated namespaces and classes 5268 also include: the namespaces and classes associated with the types of 5269 the template arguments provided for template type parameters (excluding 5270 template template parameters); the namespaces of which any template 5271 template arguments are members; and the classes of which any member 5272 templates used as template template arguments are members. [ Note: 5273 non-type template arguments do not contribute to the set of associated 5274 namespaces. --end note] */ 5275 5276 static bool 5277 arg_assoc_class (struct arg_lookup *k, tree type) 5278 { 5279 tree list; 5280 int i; 5281 5282 /* Backend build structures, such as __builtin_va_list, aren't 5283 affected by all this. */ 5284 if (!CLASS_TYPE_P (type)) 5285 return false; 5286 5287 if (vec_member (type, k->classes)) 5288 return false; 5289 VEC_safe_push (tree, gc, k->classes, type); 5290 5291 if (TYPE_CLASS_SCOPE_P (type) 5292 && arg_assoc_class_only (k, TYPE_CONTEXT (type))) 5293 return true; 5294 5295 if (arg_assoc_bases (k, type)) 5296 return true; 5297 5298 /* Process template arguments. */ 5299 if (CLASSTYPE_TEMPLATE_INFO (type) 5300 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))) 5301 { 5302 list = INNERMOST_TEMPLATE_ARGS (CLASSTYPE_TI_ARGS (type)); 5303 for (i = 0; i < TREE_VEC_LENGTH (list); ++i) 5304 if (arg_assoc_template_arg (k, TREE_VEC_ELT (list, i))) 5305 return true; 5306 } 5307 5308 return false; 5309 } 5310 5311 /* Adds everything associated with a given type. 5312 Returns 1 on error. */ 5313 5314 static bool 5315 arg_assoc_type (struct arg_lookup *k, tree type) 5316 { 5317 /* As we do not get the type of non-type dependent expressions 5318 right, we can end up with such things without a type. */ 5319 if (!type) 5320 return false; 5321 5322 if (TYPE_PTRMEM_P (type)) 5323 { 5324 /* Pointer to member: associate class type and value type. */ 5325 if (arg_assoc_type (k, TYPE_PTRMEM_CLASS_TYPE (type))) 5326 return true; 5327 return arg_assoc_type (k, TYPE_PTRMEM_POINTED_TO_TYPE (type)); 5328 } 5329 else switch (TREE_CODE (type)) 5330 { 5331 case ERROR_MARK: 5332 return false; 5333 case VOID_TYPE: 5334 case INTEGER_TYPE: 5335 case REAL_TYPE: 5336 case COMPLEX_TYPE: 5337 case VECTOR_TYPE: 5338 case BOOLEAN_TYPE: 5339 case FIXED_POINT_TYPE: 5340 case DECLTYPE_TYPE: 5341 case NULLPTR_TYPE: 5342 return false; 5343 case RECORD_TYPE: 5344 if (TYPE_PTRMEMFUNC_P (type)) 5345 return arg_assoc_type (k, TYPE_PTRMEMFUNC_FN_TYPE (type)); 5346 case UNION_TYPE: 5347 return arg_assoc_class (k, type); 5348 case POINTER_TYPE: 5349 case REFERENCE_TYPE: 5350 case ARRAY_TYPE: 5351 return arg_assoc_type (k, TREE_TYPE (type)); 5352 case ENUMERAL_TYPE: 5353 if (TYPE_CLASS_SCOPE_P (type) 5354 && arg_assoc_class_only (k, TYPE_CONTEXT (type))) 5355 return true; 5356 return arg_assoc_namespace (k, decl_namespace_context (type)); 5357 case METHOD_TYPE: 5358 /* The basetype is referenced in the first arg type, so just 5359 fall through. */ 5360 case FUNCTION_TYPE: 5361 /* Associate the parameter types. */ 5362 if (arg_assoc_args (k, TYPE_ARG_TYPES (type))) 5363 return true; 5364 /* Associate the return type. */ 5365 return arg_assoc_type (k, TREE_TYPE (type)); 5366 case TEMPLATE_TYPE_PARM: 5367 case BOUND_TEMPLATE_TEMPLATE_PARM: 5368 return false; 5369 case TYPENAME_TYPE: 5370 return false; 5371 case LANG_TYPE: 5372 gcc_assert (type == unknown_type_node 5373 || type == init_list_type_node); 5374 return false; 5375 case TYPE_PACK_EXPANSION: 5376 return arg_assoc_type (k, PACK_EXPANSION_PATTERN (type)); 5377 5378 default: 5379 gcc_unreachable (); 5380 } 5381 return false; 5382 } 5383 5384 /* Adds everything associated with arguments. Returns true on error. */ 5385 5386 static bool 5387 arg_assoc_args (struct arg_lookup *k, tree args) 5388 { 5389 for (; args; args = TREE_CHAIN (args)) 5390 if (arg_assoc (k, TREE_VALUE (args))) 5391 return true; 5392 return false; 5393 } 5394 5395 /* Adds everything associated with an argument vector. Returns true 5396 on error. */ 5397 5398 static bool 5399 arg_assoc_args_vec (struct arg_lookup *k, VEC(tree,gc) *args) 5400 { 5401 unsigned int ix; 5402 tree arg; 5403 5404 FOR_EACH_VEC_ELT (tree, args, ix, arg) 5405 if (arg_assoc (k, arg)) 5406 return true; 5407 return false; 5408 } 5409 5410 /* Adds everything associated with a given tree_node. Returns 1 on error. */ 5411 5412 static bool 5413 arg_assoc (struct arg_lookup *k, tree n) 5414 { 5415 if (n == error_mark_node) 5416 return false; 5417 5418 if (TYPE_P (n)) 5419 return arg_assoc_type (k, n); 5420 5421 if (! type_unknown_p (n)) 5422 return arg_assoc_type (k, TREE_TYPE (n)); 5423 5424 if (TREE_CODE (n) == ADDR_EXPR) 5425 n = TREE_OPERAND (n, 0); 5426 if (TREE_CODE (n) == COMPONENT_REF) 5427 n = TREE_OPERAND (n, 1); 5428 if (TREE_CODE (n) == OFFSET_REF) 5429 n = TREE_OPERAND (n, 1); 5430 while (TREE_CODE (n) == TREE_LIST) 5431 n = TREE_VALUE (n); 5432 if (BASELINK_P (n)) 5433 n = BASELINK_FUNCTIONS (n); 5434 5435 if (TREE_CODE (n) == FUNCTION_DECL) 5436 return arg_assoc_type (k, TREE_TYPE (n)); 5437 if (TREE_CODE (n) == TEMPLATE_ID_EXPR) 5438 { 5439 /* The working paper doesn't currently say how to handle template-id 5440 arguments. The sensible thing would seem to be to handle the list 5441 of template candidates like a normal overload set, and handle the 5442 template arguments like we do for class template 5443 specializations. */ 5444 tree templ = TREE_OPERAND (n, 0); 5445 tree args = TREE_OPERAND (n, 1); 5446 int ix; 5447 5448 /* First the templates. */ 5449 if (arg_assoc (k, templ)) 5450 return true; 5451 5452 /* Now the arguments. */ 5453 if (args) 5454 for (ix = TREE_VEC_LENGTH (args); ix--;) 5455 if (arg_assoc_template_arg (k, TREE_VEC_ELT (args, ix)) == 1) 5456 return true; 5457 } 5458 else if (TREE_CODE (n) == OVERLOAD) 5459 { 5460 for (; n; n = OVL_NEXT (n)) 5461 if (arg_assoc_type (k, TREE_TYPE (OVL_CURRENT (n)))) 5462 return true; 5463 } 5464 5465 return false; 5466 } 5467 5468 /* Performs Koenig lookup depending on arguments, where fns 5469 are the functions found in normal lookup. */ 5470 5471 static tree 5472 lookup_arg_dependent_1 (tree name, tree fns, VEC(tree,gc) *args, 5473 bool include_std) 5474 { 5475 struct arg_lookup k; 5476 5477 /* Remove any hidden friend functions from the list of functions 5478 found so far. They will be added back by arg_assoc_class as 5479 appropriate. */ 5480 fns = remove_hidden_names (fns); 5481 5482 k.name = name; 5483 k.args = args; 5484 k.functions = fns; 5485 k.classes = make_tree_vector (); 5486 5487 /* We previously performed an optimization here by setting 5488 NAMESPACES to the current namespace when it was safe. However, DR 5489 164 says that namespaces that were already searched in the first 5490 stage of template processing are searched again (potentially 5491 picking up later definitions) in the second stage. */ 5492 k.namespaces = make_tree_vector (); 5493 5494 /* We used to allow duplicates and let joust discard them, but 5495 since the above change for DR 164 we end up with duplicates of 5496 all the functions found by unqualified lookup. So keep track 5497 of which ones we've seen. */ 5498 if (fns) 5499 { 5500 tree ovl; 5501 /* We shouldn't be here if lookup found something other than 5502 namespace-scope functions. */ 5503 gcc_assert (DECL_NAMESPACE_SCOPE_P (OVL_CURRENT (fns))); 5504 k.fn_set = pointer_set_create (); 5505 for (ovl = fns; ovl; ovl = OVL_NEXT (ovl)) 5506 pointer_set_insert (k.fn_set, OVL_CURRENT (ovl)); 5507 } 5508 else 5509 k.fn_set = NULL; 5510 5511 if (include_std) 5512 arg_assoc_namespace (&k, std_node); 5513 arg_assoc_args_vec (&k, args); 5514 5515 fns = k.functions; 5516 5517 if (fns 5518 && TREE_CODE (fns) != VAR_DECL 5519 && !is_overloaded_fn (fns)) 5520 { 5521 error ("argument dependent lookup finds %q+D", fns); 5522 error (" in call to %qD", name); 5523 fns = error_mark_node; 5524 } 5525 5526 release_tree_vector (k.classes); 5527 release_tree_vector (k.namespaces); 5528 if (k.fn_set) 5529 pointer_set_destroy (k.fn_set); 5530 5531 return fns; 5532 } 5533 5534 /* Wrapper for lookup_arg_dependent_1. */ 5535 5536 tree 5537 lookup_arg_dependent (tree name, tree fns, VEC(tree,gc) *args, 5538 bool include_std) 5539 { 5540 tree ret; 5541 bool subtime; 5542 subtime = timevar_cond_start (TV_NAME_LOOKUP); 5543 ret = lookup_arg_dependent_1 (name, fns, args, include_std); 5544 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 5545 return ret; 5546 } 5547 5548 5549 /* Add namespace to using_directives. Return NULL_TREE if nothing was 5550 changed (i.e. there was already a directive), or the fresh 5551 TREE_LIST otherwise. */ 5552 5553 static tree 5554 push_using_directive_1 (tree used) 5555 { 5556 tree ud = current_binding_level->using_directives; 5557 tree iter, ancestor; 5558 5559 /* Check if we already have this. */ 5560 if (purpose_member (used, ud) != NULL_TREE) 5561 return NULL_TREE; 5562 5563 ancestor = namespace_ancestor (current_decl_namespace (), used); 5564 ud = current_binding_level->using_directives; 5565 ud = tree_cons (used, ancestor, ud); 5566 current_binding_level->using_directives = ud; 5567 5568 /* Recursively add all namespaces used. */ 5569 for (iter = DECL_NAMESPACE_USING (used); iter; iter = TREE_CHAIN (iter)) 5570 push_using_directive (TREE_PURPOSE (iter)); 5571 5572 return ud; 5573 } 5574 5575 /* Wrapper for push_using_directive_1. */ 5576 5577 static tree 5578 push_using_directive (tree used) 5579 { 5580 tree ret; 5581 timevar_start (TV_NAME_LOOKUP); 5582 ret = push_using_directive_1 (used); 5583 timevar_stop (TV_NAME_LOOKUP); 5584 return ret; 5585 } 5586 5587 /* The type TYPE is being declared. If it is a class template, or a 5588 specialization of a class template, do any processing required and 5589 perform error-checking. If IS_FRIEND is nonzero, this TYPE is 5590 being declared a friend. B is the binding level at which this TYPE 5591 should be bound. 5592 5593 Returns the TYPE_DECL for TYPE, which may have been altered by this 5594 processing. */ 5595 5596 static tree 5597 maybe_process_template_type_declaration (tree type, int is_friend, 5598 cp_binding_level *b) 5599 { 5600 tree decl = TYPE_NAME (type); 5601 5602 if (processing_template_parmlist) 5603 /* You can't declare a new template type in a template parameter 5604 list. But, you can declare a non-template type: 5605 5606 template <class A*> struct S; 5607 5608 is a forward-declaration of `A'. */ 5609 ; 5610 else if (b->kind == sk_namespace 5611 && current_binding_level->kind != sk_namespace) 5612 /* If this new type is being injected into a containing scope, 5613 then it's not a template type. */ 5614 ; 5615 else 5616 { 5617 gcc_assert (MAYBE_CLASS_TYPE_P (type) 5618 || TREE_CODE (type) == ENUMERAL_TYPE); 5619 5620 if (processing_template_decl) 5621 { 5622 /* This may change after the call to 5623 push_template_decl_real, but we want the original value. */ 5624 tree name = DECL_NAME (decl); 5625 5626 decl = push_template_decl_real (decl, is_friend); 5627 if (decl == error_mark_node) 5628 return error_mark_node; 5629 5630 /* If the current binding level is the binding level for the 5631 template parameters (see the comment in 5632 begin_template_parm_list) and the enclosing level is a class 5633 scope, and we're not looking at a friend, push the 5634 declaration of the member class into the class scope. In the 5635 friend case, push_template_decl will already have put the 5636 friend into global scope, if appropriate. */ 5637 if (TREE_CODE (type) != ENUMERAL_TYPE 5638 && !is_friend && b->kind == sk_template_parms 5639 && b->level_chain->kind == sk_class) 5640 { 5641 finish_member_declaration (CLASSTYPE_TI_TEMPLATE (type)); 5642 5643 if (!COMPLETE_TYPE_P (current_class_type)) 5644 { 5645 maybe_add_class_template_decl_list (current_class_type, 5646 type, /*friend_p=*/0); 5647 /* Put this UTD in the table of UTDs for the class. */ 5648 if (CLASSTYPE_NESTED_UTDS (current_class_type) == NULL) 5649 CLASSTYPE_NESTED_UTDS (current_class_type) = 5650 binding_table_new (SCOPE_DEFAULT_HT_SIZE); 5651 5652 binding_table_insert 5653 (CLASSTYPE_NESTED_UTDS (current_class_type), name, type); 5654 } 5655 } 5656 } 5657 } 5658 5659 return decl; 5660 } 5661 5662 /* Push a tag name NAME for struct/class/union/enum type TYPE. In case 5663 that the NAME is a class template, the tag is processed but not pushed. 5664 5665 The pushed scope depend on the SCOPE parameter: 5666 - When SCOPE is TS_CURRENT, put it into the inner-most non-sk_cleanup 5667 scope. 5668 - When SCOPE is TS_GLOBAL, put it in the inner-most non-class and 5669 non-template-parameter scope. This case is needed for forward 5670 declarations. 5671 - When SCOPE is TS_WITHIN_ENCLOSING_NON_CLASS, this is similar to 5672 TS_GLOBAL case except that names within template-parameter scopes 5673 are not pushed at all. 5674 5675 Returns TYPE upon success and ERROR_MARK_NODE otherwise. */ 5676 5677 static tree 5678 pushtag_1 (tree name, tree type, tag_scope scope) 5679 { 5680 cp_binding_level *b; 5681 tree decl; 5682 5683 b = current_binding_level; 5684 while (/* Cleanup scopes are not scopes from the point of view of 5685 the language. */ 5686 b->kind == sk_cleanup 5687 /* Neither are function parameter scopes. */ 5688 || b->kind == sk_function_parms 5689 /* Neither are the scopes used to hold template parameters 5690 for an explicit specialization. For an ordinary template 5691 declaration, these scopes are not scopes from the point of 5692 view of the language. */ 5693 || (b->kind == sk_template_parms 5694 && (b->explicit_spec_p || scope == ts_global)) 5695 || (b->kind == sk_class 5696 && (scope != ts_current 5697 /* We may be defining a new type in the initializer 5698 of a static member variable. We allow this when 5699 not pedantic, and it is particularly useful for 5700 type punning via an anonymous union. */ 5701 || COMPLETE_TYPE_P (b->this_entity)))) 5702 b = b->level_chain; 5703 5704 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE); 5705 5706 /* Do C++ gratuitous typedefing. */ 5707 if (identifier_type_value_1 (name) != type) 5708 { 5709 tree tdef; 5710 int in_class = 0; 5711 tree context = TYPE_CONTEXT (type); 5712 5713 if (! context) 5714 { 5715 tree cs = current_scope (); 5716 5717 if (scope == ts_current 5718 || (cs && TREE_CODE (cs) == FUNCTION_DECL)) 5719 context = cs; 5720 else if (cs != NULL_TREE && TYPE_P (cs)) 5721 /* When declaring a friend class of a local class, we want 5722 to inject the newly named class into the scope 5723 containing the local class, not the namespace 5724 scope. */ 5725 context = decl_function_context (get_type_decl (cs)); 5726 } 5727 if (!context) 5728 context = current_namespace; 5729 5730 if (b->kind == sk_class 5731 || (b->kind == sk_template_parms 5732 && b->level_chain->kind == sk_class)) 5733 in_class = 1; 5734 5735 if (current_lang_name == lang_name_java) 5736 TYPE_FOR_JAVA (type) = 1; 5737 5738 tdef = create_implicit_typedef (name, type); 5739 DECL_CONTEXT (tdef) = FROB_CONTEXT (context); 5740 if (scope == ts_within_enclosing_non_class) 5741 { 5742 /* This is a friend. Make this TYPE_DECL node hidden from 5743 ordinary name lookup. Its corresponding TEMPLATE_DECL 5744 will be marked in push_template_decl_real. */ 5745 retrofit_lang_decl (tdef); 5746 DECL_ANTICIPATED (tdef) = 1; 5747 DECL_FRIEND_P (tdef) = 1; 5748 } 5749 5750 decl = maybe_process_template_type_declaration 5751 (type, scope == ts_within_enclosing_non_class, b); 5752 if (decl == error_mark_node) 5753 return decl; 5754 5755 if (b->kind == sk_class) 5756 { 5757 if (!TYPE_BEING_DEFINED (current_class_type)) 5758 return error_mark_node; 5759 5760 if (!PROCESSING_REAL_TEMPLATE_DECL_P ()) 5761 /* Put this TYPE_DECL on the TYPE_FIELDS list for the 5762 class. But if it's a member template class, we want 5763 the TEMPLATE_DECL, not the TYPE_DECL, so this is done 5764 later. */ 5765 finish_member_declaration (decl); 5766 else 5767 pushdecl_class_level (decl); 5768 } 5769 else if (b->kind != sk_template_parms) 5770 { 5771 decl = pushdecl_with_scope_1 (decl, b, /*is_friend=*/false); 5772 if (decl == error_mark_node) 5773 return decl; 5774 } 5775 5776 if (! in_class) 5777 set_identifier_type_value_with_scope (name, tdef, b); 5778 5779 TYPE_CONTEXT (type) = DECL_CONTEXT (decl); 5780 5781 /* If this is a local class, keep track of it. We need this 5782 information for name-mangling, and so that it is possible to 5783 find all function definitions in a translation unit in a 5784 convenient way. (It's otherwise tricky to find a member 5785 function definition it's only pointed to from within a local 5786 class.) */ 5787 if (TYPE_CONTEXT (type) 5788 && TREE_CODE (TYPE_CONTEXT (type)) == FUNCTION_DECL) 5789 VEC_safe_push (tree, gc, local_classes, type); 5790 } 5791 if (b->kind == sk_class 5792 && !COMPLETE_TYPE_P (current_class_type)) 5793 { 5794 maybe_add_class_template_decl_list (current_class_type, 5795 type, /*friend_p=*/0); 5796 5797 if (CLASSTYPE_NESTED_UTDS (current_class_type) == NULL) 5798 CLASSTYPE_NESTED_UTDS (current_class_type) 5799 = binding_table_new (SCOPE_DEFAULT_HT_SIZE); 5800 5801 binding_table_insert 5802 (CLASSTYPE_NESTED_UTDS (current_class_type), name, type); 5803 } 5804 5805 decl = TYPE_NAME (type); 5806 gcc_assert (TREE_CODE (decl) == TYPE_DECL); 5807 5808 /* Set type visibility now if this is a forward declaration. */ 5809 TREE_PUBLIC (decl) = 1; 5810 determine_visibility (decl); 5811 5812 return type; 5813 } 5814 5815 /* Wrapper for pushtag_1. */ 5816 5817 tree 5818 pushtag (tree name, tree type, tag_scope scope) 5819 { 5820 tree ret; 5821 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 5822 ret = pushtag_1 (name, type, scope); 5823 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 5824 return ret; 5825 } 5826 5827 /* Subroutines for reverting temporarily to top-level for instantiation 5828 of templates and such. We actually need to clear out the class- and 5829 local-value slots of all identifiers, so that only the global values 5830 are at all visible. Simply setting current_binding_level to the global 5831 scope isn't enough, because more binding levels may be pushed. */ 5832 struct saved_scope *scope_chain; 5833 5834 /* If ID has not already been marked, add an appropriate binding to 5835 *OLD_BINDINGS. */ 5836 5837 static void 5838 store_binding (tree id, VEC(cxx_saved_binding,gc) **old_bindings) 5839 { 5840 cxx_saved_binding *saved; 5841 5842 if (!id || !IDENTIFIER_BINDING (id)) 5843 return; 5844 5845 if (IDENTIFIER_MARKED (id)) 5846 return; 5847 5848 IDENTIFIER_MARKED (id) = 1; 5849 5850 saved = VEC_safe_push (cxx_saved_binding, gc, *old_bindings, NULL); 5851 saved->identifier = id; 5852 saved->binding = IDENTIFIER_BINDING (id); 5853 saved->real_type_value = REAL_IDENTIFIER_TYPE_VALUE (id); 5854 IDENTIFIER_BINDING (id) = NULL; 5855 } 5856 5857 static void 5858 store_bindings (tree names, VEC(cxx_saved_binding,gc) **old_bindings) 5859 { 5860 tree t; 5861 5862 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 5863 for (t = names; t; t = TREE_CHAIN (t)) 5864 { 5865 tree id; 5866 5867 if (TREE_CODE (t) == TREE_LIST) 5868 id = TREE_PURPOSE (t); 5869 else 5870 id = DECL_NAME (t); 5871 5872 store_binding (id, old_bindings); 5873 } 5874 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 5875 } 5876 5877 /* Like store_bindings, but NAMES is a vector of cp_class_binding 5878 objects, rather than a TREE_LIST. */ 5879 5880 static void 5881 store_class_bindings (VEC(cp_class_binding,gc) *names, 5882 VEC(cxx_saved_binding,gc) **old_bindings) 5883 { 5884 size_t i; 5885 cp_class_binding *cb; 5886 5887 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 5888 for (i = 0; VEC_iterate(cp_class_binding, names, i, cb); ++i) 5889 store_binding (cb->identifier, old_bindings); 5890 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 5891 } 5892 5893 void 5894 push_to_top_level (void) 5895 { 5896 struct saved_scope *s; 5897 cp_binding_level *b; 5898 cxx_saved_binding *sb; 5899 size_t i; 5900 bool need_pop; 5901 5902 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 5903 s = ggc_alloc_cleared_saved_scope (); 5904 5905 b = scope_chain ? current_binding_level : 0; 5906 5907 /* If we're in the middle of some function, save our state. */ 5908 if (cfun) 5909 { 5910 need_pop = true; 5911 push_function_context (); 5912 } 5913 else 5914 need_pop = false; 5915 5916 if (scope_chain && previous_class_level) 5917 store_class_bindings (previous_class_level->class_shadowed, 5918 &s->old_bindings); 5919 5920 /* Have to include the global scope, because class-scope decls 5921 aren't listed anywhere useful. */ 5922 for (; b; b = b->level_chain) 5923 { 5924 tree t; 5925 5926 /* Template IDs are inserted into the global level. If they were 5927 inserted into namespace level, finish_file wouldn't find them 5928 when doing pending instantiations. Therefore, don't stop at 5929 namespace level, but continue until :: . */ 5930 if (global_scope_p (b)) 5931 break; 5932 5933 store_bindings (b->names, &s->old_bindings); 5934 /* We also need to check class_shadowed to save class-level type 5935 bindings, since pushclass doesn't fill in b->names. */ 5936 if (b->kind == sk_class) 5937 store_class_bindings (b->class_shadowed, &s->old_bindings); 5938 5939 /* Unwind type-value slots back to top level. */ 5940 for (t = b->type_shadowed; t; t = TREE_CHAIN (t)) 5941 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (t), TREE_VALUE (t)); 5942 } 5943 5944 FOR_EACH_VEC_ELT (cxx_saved_binding, s->old_bindings, i, sb) 5945 IDENTIFIER_MARKED (sb->identifier) = 0; 5946 5947 s->prev = scope_chain; 5948 s->bindings = b; 5949 s->need_pop_function_context = need_pop; 5950 s->function_decl = current_function_decl; 5951 s->unevaluated_operand = cp_unevaluated_operand; 5952 s->inhibit_evaluation_warnings = c_inhibit_evaluation_warnings; 5953 s->x_stmt_tree.stmts_are_full_exprs_p = true; 5954 5955 scope_chain = s; 5956 current_function_decl = NULL_TREE; 5957 current_lang_base = VEC_alloc (tree, gc, 10); 5958 current_lang_name = lang_name_cplusplus; 5959 current_namespace = global_namespace; 5960 push_class_stack (); 5961 cp_unevaluated_operand = 0; 5962 c_inhibit_evaluation_warnings = 0; 5963 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 5964 } 5965 5966 static void 5967 pop_from_top_level_1 (void) 5968 { 5969 struct saved_scope *s = scope_chain; 5970 cxx_saved_binding *saved; 5971 size_t i; 5972 5973 /* Clear out class-level bindings cache. */ 5974 if (previous_class_level) 5975 invalidate_class_lookup_cache (); 5976 pop_class_stack (); 5977 5978 current_lang_base = 0; 5979 5980 scope_chain = s->prev; 5981 FOR_EACH_VEC_ELT (cxx_saved_binding, s->old_bindings, i, saved) 5982 { 5983 tree id = saved->identifier; 5984 5985 IDENTIFIER_BINDING (id) = saved->binding; 5986 SET_IDENTIFIER_TYPE_VALUE (id, saved->real_type_value); 5987 } 5988 5989 /* If we were in the middle of compiling a function, restore our 5990 state. */ 5991 if (s->need_pop_function_context) 5992 pop_function_context (); 5993 current_function_decl = s->function_decl; 5994 cp_unevaluated_operand = s->unevaluated_operand; 5995 c_inhibit_evaluation_warnings = s->inhibit_evaluation_warnings; 5996 } 5997 5998 /* Wrapper for pop_from_top_level_1. */ 5999 6000 void 6001 pop_from_top_level (void) 6002 { 6003 bool subtime = timevar_cond_start (TV_NAME_LOOKUP); 6004 pop_from_top_level_1 (); 6005 timevar_cond_stop (TV_NAME_LOOKUP, subtime); 6006 } 6007 6008 6009 /* Pop off extraneous binding levels left over due to syntax errors. 6010 6011 We don't pop past namespaces, as they might be valid. */ 6012 6013 void 6014 pop_everything (void) 6015 { 6016 if (ENABLE_SCOPE_CHECKING) 6017 verbatim ("XXX entering pop_everything ()\n"); 6018 while (!toplevel_bindings_p ()) 6019 { 6020 if (current_binding_level->kind == sk_class) 6021 pop_nested_class (); 6022 else 6023 poplevel (0, 0, 0); 6024 } 6025 if (ENABLE_SCOPE_CHECKING) 6026 verbatim ("XXX leaving pop_everything ()\n"); 6027 } 6028 6029 /* Emit debugging information for using declarations and directives. 6030 If input tree is overloaded fn then emit debug info for all 6031 candidates. */ 6032 6033 void 6034 cp_emit_debug_info_for_using (tree t, tree context) 6035 { 6036 /* Don't try to emit any debug information if we have errors. */ 6037 if (seen_error ()) 6038 return; 6039 6040 /* Ignore this FUNCTION_DECL if it refers to a builtin declaration 6041 of a builtin function. */ 6042 if (TREE_CODE (t) == FUNCTION_DECL 6043 && DECL_EXTERNAL (t) 6044 && DECL_BUILT_IN (t)) 6045 return; 6046 6047 /* Do not supply context to imported_module_or_decl, if 6048 it is a global namespace. */ 6049 if (context == global_namespace) 6050 context = NULL_TREE; 6051 6052 if (BASELINK_P (t)) 6053 t = BASELINK_FUNCTIONS (t); 6054 6055 /* FIXME: Handle TEMPLATE_DECLs. */ 6056 for (t = OVL_CURRENT (t); t; t = OVL_NEXT (t)) 6057 if (TREE_CODE (t) != TEMPLATE_DECL) 6058 { 6059 if (building_stmt_list_p ()) 6060 add_stmt (build_stmt (input_location, USING_STMT, t)); 6061 else 6062 (*debug_hooks->imported_module_or_decl) (t, NULL_TREE, context, false); 6063 } 6064 } 6065 6066 #include "gt-cp-name-lookup.h" 6067