1 /* Process declarations and variables for C++ compiler.
2 Copyright (C) 1988-2018 Free Software Foundation, Inc.
3 Contributed by Michael Tiemann (tiemann@cygnus.com)
4
5 This file is part of GCC.
6
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
10 any later version.
11
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
20
21
22 /* Process declarations and symbol lookup for C++ front end.
23 Also constructs types; the standard scalar types at initialization,
24 and structure, union, array and enum types when they are declared. */
25
26 /* ??? not all decl nodes are given the most useful possible
27 line numbers. For example, the CONST_DECLs for enum values. */
28
29 #include "config.h"
30 #include "system.h"
31 #include "coretypes.h"
32 #include "target.h"
33 #include "c-family/c-target.h"
34 #include "cp-tree.h"
35 #include "timevar.h"
36 #include "stringpool.h"
37 #include "cgraph.h"
38 #include "stor-layout.h"
39 #include "varasm.h"
40 #include "attribs.h"
41 #include "flags.h"
42 #include "tree-iterator.h"
43 #include "decl.h"
44 #include "intl.h"
45 #include "toplev.h"
46 #include "c-family/c-objc.h"
47 #include "c-family/c-pragma.h"
48 #include "c-family/c-ubsan.h"
49 #include "debug.h"
50 #include "plugin.h"
51 #include "builtins.h"
52 #include "gimplify.h"
53 #include "asan.h"
54
55 /* Possible cases of bad specifiers type used by bad_specifiers. */
56 enum bad_spec_place {
57 BSP_VAR, /* variable */
58 BSP_PARM, /* parameter */
59 BSP_TYPE, /* type */
60 BSP_FIELD /* field */
61 };
62
63 static const char *redeclaration_error_message (tree, tree);
64
65 static int decl_jump_unsafe (tree);
66 static void require_complete_types_for_parms (tree);
67 static void push_local_name (tree);
68 static tree grok_reference_init (tree, tree, tree, int);
69 static tree grokvardecl (tree, tree, tree, const cp_decl_specifier_seq *,
70 int, int, int, bool, int, tree);
71 static int check_static_variable_definition (tree, tree);
72 static void record_unknown_type (tree, const char *);
73 static tree builtin_function_1 (tree, tree, bool);
74 static int member_function_or_else (tree, tree, enum overload_flags);
75 static tree local_variable_p_walkfn (tree *, int *, void *);
76 static const char *tag_name (enum tag_types);
77 static tree lookup_and_check_tag (enum tag_types, tree, tag_scope, bool);
78 static void maybe_deduce_size_from_array_init (tree, tree);
79 static void layout_var_decl (tree);
80 static tree check_initializer (tree, tree, int, vec<tree, va_gc> **);
81 static void make_rtl_for_nonlocal_decl (tree, tree, const char *);
82 static void save_function_data (tree);
83 static void copy_type_enum (tree , tree);
84 static void check_function_type (tree, tree);
85 static void finish_constructor_body (void);
86 static void begin_destructor_body (void);
87 static void finish_destructor_body (void);
88 static void record_key_method_defined (tree);
89 static tree create_array_type_for_decl (tree, tree, tree);
90 static tree get_atexit_node (void);
91 static tree get_dso_handle_node (void);
92 static tree start_cleanup_fn (void);
93 static void end_cleanup_fn (void);
94 static tree cp_make_fname_decl (location_t, tree, int);
95 static void initialize_predefined_identifiers (void);
96 static tree check_special_function_return_type
97 (special_function_kind, tree, tree, int, const location_t*);
98 static tree push_cp_library_fn (enum tree_code, tree, int);
99 static tree build_cp_library_fn (tree, enum tree_code, tree, int);
100 static void store_parm_decls (tree);
101 static void initialize_local_var (tree, tree);
102 static void expand_static_init (tree, tree);
103
104 /* The following symbols are subsumed in the cp_global_trees array, and
105 listed here individually for documentation purposes.
106
107 C++ extensions
108 tree wchar_decl_node;
109
110 tree vtable_entry_type;
111 tree delta_type_node;
112 tree __t_desc_type_node;
113
114 tree class_type_node;
115 tree unknown_type_node;
116
117 Array type `vtable_entry_type[]'
118
119 tree vtbl_type_node;
120 tree vtbl_ptr_type_node;
121
122 Namespaces,
123
124 tree std_node;
125 tree abi_node;
126
127 A FUNCTION_DECL which can call `abort'. Not necessarily the
128 one that the user will declare, but sufficient to be called
129 by routines that want to abort the program.
130
131 tree abort_fndecl;
132
133 Used by RTTI
134 tree type_info_type_node, tinfo_decl_id, tinfo_decl_type;
135 tree tinfo_var_id; */
136
137 tree cp_global_trees[CPTI_MAX];
138
139 #define local_names cp_function_chain->x_local_names
140
141 /* A list of objects which have constructors or destructors
142 which reside in the global scope. The decl is stored in
143 the TREE_VALUE slot and the initializer is stored
144 in the TREE_PURPOSE slot. */
145 tree static_aggregates;
146
147 /* Like static_aggregates, but for thread_local variables. */
148 tree tls_aggregates;
149
150 /* -- end of C++ */
151
152 /* A node for the integer constant 2. */
153
154 tree integer_two_node;
155
156 /* vector of static decls. */
157 vec<tree, va_gc> *static_decls;
158
159 /* vector of keyed classes. */
160 vec<tree, va_gc> *keyed_classes;
161
162 /* Used only for jumps to as-yet undefined labels, since jumps to
163 defined labels can have their validity checked immediately. */
164
165 struct GTY((chain_next ("%h.next"))) named_label_use_entry {
166 struct named_label_use_entry *next;
167 /* The binding level to which this entry is *currently* attached.
168 This is initially the binding level in which the goto appeared,
169 but is modified as scopes are closed. */
170 cp_binding_level *binding_level;
171 /* The head of the names list that was current when the goto appeared,
172 or the inner scope popped. These are the decls that will *not* be
173 skipped when jumping to the label. */
174 tree names_in_scope;
175 /* The location of the goto, for error reporting. */
176 location_t o_goto_locus;
177 /* True if an OpenMP structured block scope has been closed since
178 the goto appeared. This means that the branch from the label will
179 illegally exit an OpenMP scope. */
180 bool in_omp_scope;
181 };
182
183 /* A list of all LABEL_DECLs in the function that have names. Here so
184 we can clear out their names' definitions at the end of the
185 function, and so we can check the validity of jumps to these labels. */
186
187 struct GTY((for_user)) named_label_entry {
188
189 tree name; /* Name of decl. */
190
191 tree label_decl; /* LABEL_DECL, unless deleted local label. */
192
193 named_label_entry *outer; /* Outer shadowed chain. */
194
195 /* The binding level to which the label is *currently* attached.
196 This is initially set to the binding level in which the label
197 is defined, but is modified as scopes are closed. */
198 cp_binding_level *binding_level;
199
200 /* The head of the names list that was current when the label was
201 defined, or the inner scope popped. These are the decls that will
202 be skipped when jumping to the label. */
203 tree names_in_scope;
204
205 /* A vector of all decls from all binding levels that would be
206 crossed by a backward branch to the label. */
207 vec<tree, va_gc> *bad_decls;
208
209 /* A list of uses of the label, before the label is defined. */
210 named_label_use_entry *uses;
211
212 /* The following bits are set after the label is defined, and are
213 updated as scopes are popped. They indicate that a jump to the
214 label will illegally enter a scope of the given flavor. */
215 bool in_try_scope;
216 bool in_catch_scope;
217 bool in_omp_scope;
218 bool in_transaction_scope;
219 bool in_constexpr_if;
220 };
221
222 #define named_labels cp_function_chain->x_named_labels
223
224 /* The number of function bodies which we are currently processing.
225 (Zero if we are at namespace scope, one inside the body of a
226 function, two inside the body of a function in a local class, etc.) */
227 int function_depth;
228
229 /* Whether the exception-specifier is part of a function type (i.e. C++17). */
230 bool flag_noexcept_type;
231
232 /* States indicating how grokdeclarator() should handle declspecs marked
233 with __attribute__((deprecated)). An object declared as
234 __attribute__((deprecated)) suppresses warnings of uses of other
235 deprecated items. */
236 enum deprecated_states deprecated_state = DEPRECATED_NORMAL;
237
238
239 /* A list of VAR_DECLs whose type was incomplete at the time the
240 variable was declared. */
241
242 struct GTY(()) incomplete_var {
243 tree decl;
244 tree incomplete_type;
245 };
246
247
248 static GTY(()) vec<incomplete_var, va_gc> *incomplete_vars;
249
250 /* Returns the kind of template specialization we are currently
251 processing, given that it's declaration contained N_CLASS_SCOPES
252 explicit scope qualifications. */
253
254 tmpl_spec_kind
current_tmpl_spec_kind(int n_class_scopes)255 current_tmpl_spec_kind (int n_class_scopes)
256 {
257 int n_template_parm_scopes = 0;
258 int seen_specialization_p = 0;
259 int innermost_specialization_p = 0;
260 cp_binding_level *b;
261
262 /* Scan through the template parameter scopes. */
263 for (b = current_binding_level;
264 b->kind == sk_template_parms;
265 b = b->level_chain)
266 {
267 /* If we see a specialization scope inside a parameter scope,
268 then something is wrong. That corresponds to a declaration
269 like:
270
271 template <class T> template <> ...
272
273 which is always invalid since [temp.expl.spec] forbids the
274 specialization of a class member template if the enclosing
275 class templates are not explicitly specialized as well. */
276 if (b->explicit_spec_p)
277 {
278 if (n_template_parm_scopes == 0)
279 innermost_specialization_p = 1;
280 else
281 seen_specialization_p = 1;
282 }
283 else if (seen_specialization_p == 1)
284 return tsk_invalid_member_spec;
285
286 ++n_template_parm_scopes;
287 }
288
289 /* Handle explicit instantiations. */
290 if (processing_explicit_instantiation)
291 {
292 if (n_template_parm_scopes != 0)
293 /* We've seen a template parameter list during an explicit
294 instantiation. For example:
295
296 template <class T> template void f(int);
297
298 This is erroneous. */
299 return tsk_invalid_expl_inst;
300 else
301 return tsk_expl_inst;
302 }
303
304 if (n_template_parm_scopes < n_class_scopes)
305 /* We've not seen enough template headers to match all the
306 specialized classes present. For example:
307
308 template <class T> void R<T>::S<T>::f(int);
309
310 This is invalid; there needs to be one set of template
311 parameters for each class. */
312 return tsk_insufficient_parms;
313 else if (n_template_parm_scopes == n_class_scopes)
314 /* We're processing a non-template declaration (even though it may
315 be a member of a template class.) For example:
316
317 template <class T> void S<T>::f(int);
318
319 The `class T' matches the `S<T>', leaving no template headers
320 corresponding to the `f'. */
321 return tsk_none;
322 else if (n_template_parm_scopes > n_class_scopes + 1)
323 /* We've got too many template headers. For example:
324
325 template <> template <class T> void f (T);
326
327 There need to be more enclosing classes. */
328 return tsk_excessive_parms;
329 else
330 /* This must be a template. It's of the form:
331
332 template <class T> template <class U> void S<T>::f(U);
333
334 This is a specialization if the innermost level was a
335 specialization; otherwise it's just a definition of the
336 template. */
337 return innermost_specialization_p ? tsk_expl_spec : tsk_template;
338 }
339
340 /* Exit the current scope. */
341
342 void
finish_scope(void)343 finish_scope (void)
344 {
345 poplevel (0, 0, 0);
346 }
347
348 /* When a label goes out of scope, check to see if that label was used
349 in a valid manner, and issue any appropriate warnings or errors. */
350
351 static void
check_label_used(tree label)352 check_label_used (tree label)
353 {
354 if (!processing_template_decl)
355 {
356 if (DECL_INITIAL (label) == NULL_TREE)
357 {
358 location_t location;
359
360 error ("label %q+D used but not defined", label);
361 location = input_location;
362 /* FIXME want (LOCATION_FILE (input_location), (line)0) */
363 /* Avoid crashing later. */
364 define_label (location, DECL_NAME (label));
365 }
366 else
367 warn_for_unused_label (label);
368 }
369 }
370
371 /* Helper function to sort named label entries in a vector by DECL_UID. */
372
373 static int
sort_labels(const void * a,const void * b)374 sort_labels (const void *a, const void *b)
375 {
376 tree label1 = *(tree const *) a;
377 tree label2 = *(tree const *) b;
378
379 /* DECL_UIDs can never be equal. */
380 return DECL_UID (label1) > DECL_UID (label2) ? -1 : +1;
381 }
382
383 /* At the end of a function, all labels declared within the function
384 go out of scope. BLOCK is the top-level block for the
385 function. */
386
387 static void
pop_labels(tree block)388 pop_labels (tree block)
389 {
390 if (!named_labels)
391 return;
392
393 /* We need to add the labels to the block chain, so debug
394 information is emitted. But, we want the order to be stable so
395 need to sort them first. Otherwise the debug output could be
396 randomly ordered. I guess it's mostly stable, unless the hash
397 table implementation changes. */
398 auto_vec<tree, 32> labels (named_labels->elements ());
399 hash_table<named_label_hash>::iterator end (named_labels->end ());
400 for (hash_table<named_label_hash>::iterator iter
401 (named_labels->begin ()); iter != end; ++iter)
402 {
403 named_label_entry *ent = *iter;
404
405 gcc_checking_assert (!ent->outer);
406 if (ent->label_decl)
407 labels.quick_push (ent->label_decl);
408 ggc_free (ent);
409 }
410 named_labels = NULL;
411 labels.qsort (sort_labels);
412
413 while (labels.length ())
414 {
415 tree label = labels.pop ();
416
417 DECL_CHAIN (label) = BLOCK_VARS (block);
418 BLOCK_VARS (block) = label;
419
420 check_label_used (label);
421 }
422 }
423
424 /* At the end of a block with local labels, restore the outer definition. */
425
426 static void
pop_local_label(tree id,tree label)427 pop_local_label (tree id, tree label)
428 {
429 check_label_used (label);
430 named_label_entry **slot = named_labels->find_slot_with_hash
431 (id, IDENTIFIER_HASH_VALUE (id), NO_INSERT);
432 named_label_entry *ent = *slot;
433
434 if (ent->outer)
435 ent = ent->outer;
436 else
437 {
438 ent = ggc_cleared_alloc<named_label_entry> ();
439 ent->name = id;
440 }
441 *slot = ent;
442 }
443
444 /* The following two routines are used to interface to Objective-C++.
445 The binding level is purposely treated as an opaque type. */
446
447 void *
objc_get_current_scope(void)448 objc_get_current_scope (void)
449 {
450 return current_binding_level;
451 }
452
453 /* The following routine is used by the NeXT-style SJLJ exceptions;
454 variables get marked 'volatile' so as to not be clobbered by
455 _setjmp()/_longjmp() calls. All variables in the current scope,
456 as well as parent scopes up to (but not including) ENCLOSING_BLK
457 shall be thusly marked. */
458
459 void
objc_mark_locals_volatile(void * enclosing_blk)460 objc_mark_locals_volatile (void *enclosing_blk)
461 {
462 cp_binding_level *scope;
463
464 for (scope = current_binding_level;
465 scope && scope != enclosing_blk;
466 scope = scope->level_chain)
467 {
468 tree decl;
469
470 for (decl = scope->names; decl; decl = TREE_CHAIN (decl))
471 objc_volatilize_decl (decl);
472
473 /* Do not climb up past the current function. */
474 if (scope->kind == sk_function_parms)
475 break;
476 }
477 }
478
479 /* True if B is the level for the condition of a constexpr if. */
480
481 static bool
level_for_constexpr_if(cp_binding_level * b)482 level_for_constexpr_if (cp_binding_level *b)
483 {
484 return (b->kind == sk_cond && b->this_entity
485 && TREE_CODE (b->this_entity) == IF_STMT
486 && IF_STMT_CONSTEXPR_P (b->this_entity));
487 }
488
489 /* Update data for defined and undefined labels when leaving a scope. */
490
491 int
poplevel_named_label_1(named_label_entry ** slot,cp_binding_level * bl)492 poplevel_named_label_1 (named_label_entry **slot, cp_binding_level *bl)
493 {
494 named_label_entry *ent = *slot;
495 cp_binding_level *obl = bl->level_chain;
496
497 if (ent->binding_level == bl)
498 {
499 tree decl;
500
501 /* ENT->NAMES_IN_SCOPE may contain a mixture of DECLs and
502 TREE_LISTs representing OVERLOADs, so be careful. */
503 for (decl = ent->names_in_scope; decl; decl = (DECL_P (decl)
504 ? DECL_CHAIN (decl)
505 : TREE_CHAIN (decl)))
506 if (decl_jump_unsafe (decl))
507 vec_safe_push (ent->bad_decls, decl);
508
509 ent->binding_level = obl;
510 ent->names_in_scope = obl->names;
511 switch (bl->kind)
512 {
513 case sk_try:
514 ent->in_try_scope = true;
515 break;
516 case sk_catch:
517 ent->in_catch_scope = true;
518 break;
519 case sk_omp:
520 ent->in_omp_scope = true;
521 break;
522 case sk_transaction:
523 ent->in_transaction_scope = true;
524 break;
525 case sk_block:
526 if (level_for_constexpr_if (bl->level_chain))
527 ent->in_constexpr_if = true;
528 break;
529 default:
530 break;
531 }
532 }
533 else if (ent->uses)
534 {
535 struct named_label_use_entry *use;
536
537 for (use = ent->uses; use ; use = use->next)
538 if (use->binding_level == bl)
539 {
540 use->binding_level = obl;
541 use->names_in_scope = obl->names;
542 if (bl->kind == sk_omp)
543 use->in_omp_scope = true;
544 }
545 }
546
547 return 1;
548 }
549
550 /* Saved errorcount to avoid -Wunused-but-set-{parameter,variable} warnings
551 when errors were reported, except for -Werror-unused-but-set-*. */
552 static int unused_but_set_errorcount;
553
554 /* Exit a binding level.
555 Pop the level off, and restore the state of the identifier-decl mappings
556 that were in effect when this level was entered.
557
558 If KEEP == 1, this level had explicit declarations, so
559 and create a "block" (a BLOCK node) for the level
560 to record its declarations and subblocks for symbol table output.
561
562 If FUNCTIONBODY is nonzero, this level is the body of a function,
563 so create a block as if KEEP were set and also clear out all
564 label names.
565
566 If REVERSE is nonzero, reverse the order of decls before putting
567 them into the BLOCK. */
568
569 tree
poplevel(int keep,int reverse,int functionbody)570 poplevel (int keep, int reverse, int functionbody)
571 {
572 tree link;
573 /* The chain of decls was accumulated in reverse order.
574 Put it into forward order, just for cleanliness. */
575 tree decls;
576 tree subblocks;
577 tree block;
578 tree decl;
579 int leaving_for_scope;
580 scope_kind kind;
581 unsigned ix;
582
583 bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
584 restart:
585
586 block = NULL_TREE;
587
588 gcc_assert (current_binding_level->kind != sk_class
589 && current_binding_level->kind != sk_namespace);
590
591 if (current_binding_level->kind == sk_cleanup)
592 functionbody = 0;
593 subblocks = functionbody >= 0 ? current_binding_level->blocks : 0;
594
595 gcc_assert (!vec_safe_length (current_binding_level->class_shadowed));
596
597 /* We used to use KEEP == 2 to indicate that the new block should go
598 at the beginning of the list of blocks at this binding level,
599 rather than the end. This hack is no longer used. */
600 gcc_assert (keep == 0 || keep == 1);
601
602 if (current_binding_level->keep)
603 keep = 1;
604
605 /* Any uses of undefined labels, and any defined labels, now operate
606 under constraints of next binding contour. */
607 if (cfun && !functionbody && named_labels)
608 named_labels->traverse<cp_binding_level *, poplevel_named_label_1>
609 (current_binding_level);
610
611 /* Get the decls in the order they were written.
612 Usually current_binding_level->names is in reverse order.
613 But parameter decls were previously put in forward order. */
614
615 decls = current_binding_level->names;
616 if (reverse)
617 {
618 decls = nreverse (decls);
619 current_binding_level->names = decls;
620 }
621
622 /* If there were any declarations or structure tags in that level,
623 or if this level is a function body,
624 create a BLOCK to record them for the life of this function. */
625 block = NULL_TREE;
626 /* Avoid function body block if possible. */
627 if (functionbody && subblocks && BLOCK_CHAIN (subblocks) == NULL_TREE)
628 keep = 0;
629 else if (keep == 1 || functionbody)
630 block = make_node (BLOCK);
631 if (block != NULL_TREE)
632 {
633 BLOCK_VARS (block) = decls;
634 BLOCK_SUBBLOCKS (block) = subblocks;
635 }
636
637 /* In each subblock, record that this is its superior. */
638 if (keep >= 0)
639 for (link = subblocks; link; link = BLOCK_CHAIN (link))
640 BLOCK_SUPERCONTEXT (link) = block;
641
642 /* We still support the old for-scope rules, whereby the variables
643 in a init statement were in scope after the for-statement ended.
644 We only use the new rules if flag_new_for_scope is nonzero. */
645 leaving_for_scope
646 = current_binding_level->kind == sk_for && flag_new_for_scope;
647
648 /* Before we remove the declarations first check for unused variables. */
649 if ((warn_unused_variable || warn_unused_but_set_variable)
650 && current_binding_level->kind != sk_template_parms
651 && !processing_template_decl)
652 for (tree d = get_local_decls (); d; d = TREE_CHAIN (d))
653 {
654 /* There are cases where D itself is a TREE_LIST. See in
655 push_local_binding where the list of decls returned by
656 getdecls is built. */
657 decl = TREE_CODE (d) == TREE_LIST ? TREE_VALUE (d) : d;
658
659 tree type = TREE_TYPE (decl);
660 if (VAR_P (decl)
661 && (! TREE_USED (decl) || !DECL_READ_P (decl))
662 && ! DECL_IN_SYSTEM_HEADER (decl)
663 /* For structured bindings, consider only real variables, not
664 subobjects. */
665 && (DECL_DECOMPOSITION_P (decl) ? !DECL_DECOMP_BASE (decl)
666 : (DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)))
667 && type != error_mark_node
668 && (!CLASS_TYPE_P (type)
669 || !TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
670 || lookup_attribute ("warn_unused",
671 TYPE_ATTRIBUTES (TREE_TYPE (decl)))))
672 {
673 if (! TREE_USED (decl))
674 {
675 if (!DECL_NAME (decl) && DECL_DECOMPOSITION_P (decl))
676 warning_at (DECL_SOURCE_LOCATION (decl),
677 OPT_Wunused_variable,
678 "unused structured binding declaration");
679 else
680 warning_at (DECL_SOURCE_LOCATION (decl),
681 OPT_Wunused_variable, "unused variable %qD", decl);
682 }
683 else if (DECL_CONTEXT (decl) == current_function_decl
684 // For -Wunused-but-set-variable leave references alone.
685 && TREE_CODE (TREE_TYPE (decl)) != REFERENCE_TYPE
686 && errorcount == unused_but_set_errorcount)
687 {
688 if (!DECL_NAME (decl) && DECL_DECOMPOSITION_P (decl))
689 warning_at (DECL_SOURCE_LOCATION (decl),
690 OPT_Wunused_but_set_variable, "structured "
691 "binding declaration set but not used");
692 else
693 warning_at (DECL_SOURCE_LOCATION (decl),
694 OPT_Wunused_but_set_variable,
695 "variable %qD set but not used", decl);
696 unused_but_set_errorcount = errorcount;
697 }
698 }
699 }
700
701 /* Remove declarations for all the DECLs in this level. */
702 for (link = decls; link; link = TREE_CHAIN (link))
703 {
704 decl = TREE_CODE (link) == TREE_LIST ? TREE_VALUE (link) : link;
705 tree name = OVL_NAME (decl);
706
707 if (leaving_for_scope && VAR_P (decl)
708 /* It's hard to make this ARM compatibility hack play nicely with
709 lambdas, and it really isn't necessary in C++11 mode. */
710 && cxx_dialect < cxx11
711 && name)
712 {
713 cxx_binding *ob = outer_binding (name,
714 IDENTIFIER_BINDING (name),
715 /*class_p=*/true);
716 tree ns_binding = NULL_TREE;
717 if (!ob)
718 ns_binding = get_namespace_binding (current_namespace, name);
719
720 if (ob && ob->scope == current_binding_level->level_chain)
721 /* We have something like:
722
723 int i;
724 for (int i; ;);
725
726 and we are leaving the `for' scope. There's no reason to
727 keep the binding of the inner `i' in this case. */
728 ;
729 else if ((ob && (TREE_CODE (ob->value) == TYPE_DECL))
730 || (ns_binding && TREE_CODE (ns_binding) == TYPE_DECL))
731 /* Here, we have something like:
732
733 typedef int I;
734
735 void f () {
736 for (int I; ;);
737 }
738
739 We must pop the for-scope binding so we know what's a
740 type and what isn't. */
741 ;
742 else
743 {
744 /* Mark this VAR_DECL as dead so that we can tell we left it
745 there only for backward compatibility. */
746 DECL_DEAD_FOR_LOCAL (link) = 1;
747
748 /* Keep track of what should have happened when we
749 popped the binding. */
750 if (ob && ob->value)
751 {
752 SET_DECL_SHADOWED_FOR_VAR (link, ob->value);
753 DECL_HAS_SHADOWED_FOR_VAR_P (link) = 1;
754 }
755
756 /* Add it to the list of dead variables in the next
757 outermost binding to that we can remove these when we
758 leave that binding. */
759 vec_safe_push (
760 current_binding_level->level_chain->dead_vars_from_for,
761 link);
762
763 /* Although we don't pop the cxx_binding, we do clear
764 its SCOPE since the scope is going away now. */
765 IDENTIFIER_BINDING (name)->scope
766 = current_binding_level->level_chain;
767
768 /* Don't remove the binding. */
769 name = NULL_TREE;
770 }
771 }
772 /* Remove the binding. */
773 if (TREE_CODE (decl) == LABEL_DECL)
774 pop_local_label (name, decl);
775 else
776 pop_local_binding (name, decl);
777 }
778
779 /* Remove declarations for any `for' variables from inner scopes
780 that we kept around. */
781 FOR_EACH_VEC_SAFE_ELT_REVERSE (current_binding_level->dead_vars_from_for,
782 ix, decl)
783 pop_local_binding (DECL_NAME (decl), decl);
784
785 /* Restore the IDENTIFIER_TYPE_VALUEs. */
786 for (link = current_binding_level->type_shadowed;
787 link; link = TREE_CHAIN (link))
788 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (link), TREE_VALUE (link));
789
790 /* There may be OVERLOADs (wrapped in TREE_LISTs) on the BLOCK_VARs
791 list if a `using' declaration put them there. The debugging
792 back ends won't understand OVERLOAD, so we remove them here.
793 Because the BLOCK_VARS are (temporarily) shared with
794 CURRENT_BINDING_LEVEL->NAMES we must do this fixup after we have
795 popped all the bindings. Also remove undeduced 'auto' decls,
796 which LTO doesn't understand, and can't have been used by anything. */
797 if (block)
798 {
799 tree* d;
800
801 for (d = &BLOCK_VARS (block); *d; )
802 {
803 if (TREE_CODE (*d) == TREE_LIST
804 || (!processing_template_decl
805 && undeduced_auto_decl (*d)))
806 *d = TREE_CHAIN (*d);
807 else
808 d = &DECL_CHAIN (*d);
809 }
810 }
811
812 /* If the level being exited is the top level of a function,
813 check over all the labels. */
814 if (functionbody)
815 {
816 if (block)
817 {
818 /* Since this is the top level block of a function, the vars are
819 the function's parameters. Don't leave them in the BLOCK
820 because they are found in the FUNCTION_DECL instead. */
821 BLOCK_VARS (block) = 0;
822 pop_labels (block);
823 }
824 else
825 pop_labels (subblocks);
826 }
827
828 kind = current_binding_level->kind;
829 if (kind == sk_cleanup)
830 {
831 tree stmt;
832
833 /* If this is a temporary binding created for a cleanup, then we'll
834 have pushed a statement list level. Pop that, create a new
835 BIND_EXPR for the block, and insert it into the stream. */
836 stmt = pop_stmt_list (current_binding_level->statement_list);
837 stmt = c_build_bind_expr (input_location, block, stmt);
838 add_stmt (stmt);
839 }
840
841 leave_scope ();
842 if (functionbody)
843 {
844 /* The current function is being defined, so its DECL_INITIAL
845 should be error_mark_node. */
846 gcc_assert (DECL_INITIAL (current_function_decl) == error_mark_node);
847 DECL_INITIAL (current_function_decl) = block ? block : subblocks;
848 if (subblocks)
849 {
850 if (FUNCTION_NEEDS_BODY_BLOCK (current_function_decl))
851 {
852 if (BLOCK_SUBBLOCKS (subblocks))
853 BLOCK_OUTER_CURLY_BRACE_P (BLOCK_SUBBLOCKS (subblocks)) = 1;
854 }
855 else
856 BLOCK_OUTER_CURLY_BRACE_P (subblocks) = 1;
857 }
858 }
859 else if (block)
860 current_binding_level->blocks
861 = block_chainon (current_binding_level->blocks, block);
862
863 /* If we did not make a block for the level just exited,
864 any blocks made for inner levels
865 (since they cannot be recorded as subblocks in that level)
866 must be carried forward so they will later become subblocks
867 of something else. */
868 else if (subblocks)
869 current_binding_level->blocks
870 = block_chainon (current_binding_level->blocks, subblocks);
871
872 /* Each and every BLOCK node created here in `poplevel' is important
873 (e.g. for proper debugging information) so if we created one
874 earlier, mark it as "used". */
875 if (block)
876 TREE_USED (block) = 1;
877
878 /* All temporary bindings created for cleanups are popped silently. */
879 if (kind == sk_cleanup)
880 goto restart;
881
882 timevar_cond_stop (TV_NAME_LOOKUP, subtime);
883 return block;
884 }
885
886 /* Call wrapup_globals_declarations for the globals in NAMESPACE. */
887 /* Diagnose odr-used extern inline variables without definitions
888 in the current TU. */
889
890 int
wrapup_namespace_globals()891 wrapup_namespace_globals ()
892 {
893 if (vec<tree, va_gc> *statics = static_decls)
894 {
895 tree decl;
896 unsigned int i;
897 FOR_EACH_VEC_ELT (*statics, i, decl)
898 {
899 if (warn_unused_function
900 && TREE_CODE (decl) == FUNCTION_DECL
901 && DECL_INITIAL (decl) == 0
902 && DECL_EXTERNAL (decl)
903 && !TREE_PUBLIC (decl)
904 && !DECL_ARTIFICIAL (decl)
905 && !DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)
906 && !TREE_NO_WARNING (decl))
907 warning_at (DECL_SOURCE_LOCATION (decl),
908 OPT_Wunused_function,
909 "%qF declared %<static%> but never defined", decl);
910
911 if (VAR_P (decl)
912 && DECL_EXTERNAL (decl)
913 && DECL_INLINE_VAR_P (decl)
914 && DECL_ODR_USED (decl))
915 error_at (DECL_SOURCE_LOCATION (decl),
916 "odr-used inline variable %qD is not defined", decl);
917 }
918
919 /* Clear out the list, so we don't rescan next time. */
920 static_decls = NULL;
921
922 /* Write out any globals that need to be output. */
923 return wrapup_global_declarations (statics->address (),
924 statics->length ());
925 }
926 return 0;
927 }
928
929 /* In C++, you don't have to write `struct S' to refer to `S'; you
930 can just use `S'. We accomplish this by creating a TYPE_DECL as
931 if the user had written `typedef struct S S'. Create and return
932 the TYPE_DECL for TYPE. */
933
934 tree
create_implicit_typedef(tree name,tree type)935 create_implicit_typedef (tree name, tree type)
936 {
937 tree decl;
938
939 decl = build_decl (input_location, TYPE_DECL, name, type);
940 DECL_ARTIFICIAL (decl) = 1;
941 /* There are other implicit type declarations, like the one *within*
942 a class that allows you to write `S::S'. We must distinguish
943 amongst these. */
944 SET_DECL_IMPLICIT_TYPEDEF_P (decl);
945 TYPE_NAME (type) = decl;
946 TYPE_STUB_DECL (type) = decl;
947
948 return decl;
949 }
950
951 /* Remember a local name for name-mangling purposes. */
952
953 static void
push_local_name(tree decl)954 push_local_name (tree decl)
955 {
956 size_t i, nelts;
957 tree t, name;
958
959 timevar_start (TV_NAME_LOOKUP);
960
961 name = DECL_NAME (decl);
962
963 nelts = vec_safe_length (local_names);
964 for (i = 0; i < nelts; i++)
965 {
966 t = (*local_names)[i];
967 if (DECL_NAME (t) == name)
968 {
969 retrofit_lang_decl (decl);
970 DECL_LANG_SPECIFIC (decl)->u.base.u2sel = 1;
971 if (DECL_DISCRIMINATOR_SET_P (t))
972 DECL_DISCRIMINATOR (decl) = DECL_DISCRIMINATOR (t) + 1;
973 else
974 DECL_DISCRIMINATOR (decl) = 1;
975
976 (*local_names)[i] = decl;
977 timevar_stop (TV_NAME_LOOKUP);
978 return;
979 }
980 }
981
982 vec_safe_push (local_names, decl);
983 timevar_stop (TV_NAME_LOOKUP);
984 }
985
986 /* Subroutine of duplicate_decls: return truthvalue of whether
987 or not types of these decls match.
988
989 For C++, we must compare the parameter list so that `int' can match
990 `int&' in a parameter position, but `int&' is not confused with
991 `const int&'. */
992
993 int
decls_match(tree newdecl,tree olddecl,bool record_versions)994 decls_match (tree newdecl, tree olddecl, bool record_versions /* = true */)
995 {
996 int types_match;
997
998 if (newdecl == olddecl)
999 return 1;
1000
1001 if (TREE_CODE (newdecl) != TREE_CODE (olddecl))
1002 /* If the two DECLs are not even the same kind of thing, we're not
1003 interested in their types. */
1004 return 0;
1005
1006 gcc_assert (DECL_P (newdecl));
1007
1008 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1009 {
1010 tree f1 = TREE_TYPE (newdecl);
1011 tree f2 = TREE_TYPE (olddecl);
1012 tree p1 = TYPE_ARG_TYPES (f1);
1013 tree p2 = TYPE_ARG_TYPES (f2);
1014 tree r2;
1015
1016 /* Specializations of different templates are different functions
1017 even if they have the same type. */
1018 tree t1 = (DECL_USE_TEMPLATE (newdecl)
1019 ? DECL_TI_TEMPLATE (newdecl)
1020 : NULL_TREE);
1021 tree t2 = (DECL_USE_TEMPLATE (olddecl)
1022 ? DECL_TI_TEMPLATE (olddecl)
1023 : NULL_TREE);
1024 if (t1 != t2)
1025 return 0;
1026
1027 if (CP_DECL_CONTEXT (newdecl) != CP_DECL_CONTEXT (olddecl)
1028 && ! (DECL_EXTERN_C_P (newdecl)
1029 && DECL_EXTERN_C_P (olddecl)))
1030 return 0;
1031
1032 /* A new declaration doesn't match a built-in one unless it
1033 is also extern "C". */
1034 if (DECL_IS_BUILTIN (olddecl)
1035 && DECL_EXTERN_C_P (olddecl) && !DECL_EXTERN_C_P (newdecl))
1036 return 0;
1037
1038 if (TREE_CODE (f1) != TREE_CODE (f2))
1039 return 0;
1040
1041 /* A declaration with deduced return type should use its pre-deduction
1042 type for declaration matching. */
1043 r2 = fndecl_declared_return_type (olddecl);
1044
1045 if (same_type_p (TREE_TYPE (f1), r2))
1046 {
1047 if (!prototype_p (f2) && DECL_EXTERN_C_P (olddecl)
1048 && (DECL_BUILT_IN (olddecl)
1049 #ifndef NO_IMPLICIT_EXTERN_C
1050 || (DECL_IN_SYSTEM_HEADER (newdecl) && !DECL_CLASS_SCOPE_P (newdecl))
1051 || (DECL_IN_SYSTEM_HEADER (olddecl) && !DECL_CLASS_SCOPE_P (olddecl))
1052 #endif
1053 ))
1054 {
1055 types_match = self_promoting_args_p (p1);
1056 if (p1 == void_list_node)
1057 TREE_TYPE (newdecl) = TREE_TYPE (olddecl);
1058 }
1059 #ifndef NO_IMPLICIT_EXTERN_C
1060 else if (!prototype_p (f1)
1061 && (DECL_EXTERN_C_P (olddecl)
1062 && DECL_IN_SYSTEM_HEADER (olddecl)
1063 && !DECL_CLASS_SCOPE_P (olddecl))
1064 && (DECL_EXTERN_C_P (newdecl)
1065 && DECL_IN_SYSTEM_HEADER (newdecl)
1066 && !DECL_CLASS_SCOPE_P (newdecl)))
1067 {
1068 types_match = self_promoting_args_p (p2);
1069 TREE_TYPE (newdecl) = TREE_TYPE (olddecl);
1070 }
1071 #endif
1072 else
1073 types_match =
1074 compparms (p1, p2)
1075 && type_memfn_rqual (f1) == type_memfn_rqual (f2)
1076 && (TYPE_ATTRIBUTES (TREE_TYPE (newdecl)) == NULL_TREE
1077 || comp_type_attributes (TREE_TYPE (newdecl),
1078 TREE_TYPE (olddecl)) != 0);
1079 }
1080 else
1081 types_match = 0;
1082
1083 /* The decls dont match if they correspond to two different versions
1084 of the same function. Disallow extern "C" functions to be
1085 versions for now. */
1086 if (types_match
1087 && !DECL_EXTERN_C_P (newdecl)
1088 && !DECL_EXTERN_C_P (olddecl)
1089 && record_versions
1090 && maybe_version_functions (newdecl, olddecl,
1091 (!DECL_FUNCTION_VERSIONED (newdecl)
1092 || !DECL_FUNCTION_VERSIONED (olddecl))))
1093 return 0;
1094 }
1095 else if (TREE_CODE (newdecl) == TEMPLATE_DECL)
1096 {
1097 tree oldres = DECL_TEMPLATE_RESULT (olddecl);
1098 tree newres = DECL_TEMPLATE_RESULT (newdecl);
1099
1100 if (TREE_CODE (newres) != TREE_CODE (oldres))
1101 return 0;
1102
1103 if (!comp_template_parms (DECL_TEMPLATE_PARMS (newdecl),
1104 DECL_TEMPLATE_PARMS (olddecl)))
1105 return 0;
1106
1107 if (TREE_CODE (DECL_TEMPLATE_RESULT (newdecl)) == TYPE_DECL)
1108 types_match = (same_type_p (TREE_TYPE (oldres), TREE_TYPE (newres))
1109 && equivalently_constrained (olddecl, newdecl));
1110 else
1111 // We don't need to check equivalently_constrained for variable and
1112 // function templates because we check it on the results.
1113 types_match = decls_match (oldres, newres);
1114 }
1115 else
1116 {
1117 /* Need to check scope for variable declaration (VAR_DECL).
1118 For typedef (TYPE_DECL), scope is ignored. */
1119 if (VAR_P (newdecl)
1120 && CP_DECL_CONTEXT (newdecl) != CP_DECL_CONTEXT (olddecl)
1121 /* [dcl.link]
1122 Two declarations for an object with C language linkage
1123 with the same name (ignoring the namespace that qualify
1124 it) that appear in different namespace scopes refer to
1125 the same object. */
1126 && !(DECL_EXTERN_C_P (olddecl) && DECL_EXTERN_C_P (newdecl)))
1127 return 0;
1128
1129 if (TREE_TYPE (newdecl) == error_mark_node)
1130 types_match = TREE_TYPE (olddecl) == error_mark_node;
1131 else if (TREE_TYPE (olddecl) == NULL_TREE)
1132 types_match = TREE_TYPE (newdecl) == NULL_TREE;
1133 else if (TREE_TYPE (newdecl) == NULL_TREE)
1134 types_match = 0;
1135 else
1136 types_match = comptypes (TREE_TYPE (newdecl),
1137 TREE_TYPE (olddecl),
1138 COMPARE_REDECLARATION);
1139 }
1140
1141 // Normal functions can be constrained, as can variable partial
1142 // specializations.
1143 if (types_match && VAR_OR_FUNCTION_DECL_P (newdecl))
1144 types_match = equivalently_constrained (newdecl, olddecl);
1145
1146 return types_match;
1147 }
1148
1149 /* NEWDECL and OLDDECL have identical signatures. If they are
1150 different versions adjust them and return true.
1151 If RECORD is set to true, record function versions. */
1152
1153 bool
maybe_version_functions(tree newdecl,tree olddecl,bool record)1154 maybe_version_functions (tree newdecl, tree olddecl, bool record)
1155 {
1156 if (!targetm.target_option.function_versions (newdecl, olddecl))
1157 return false;
1158
1159 if (!DECL_FUNCTION_VERSIONED (olddecl))
1160 {
1161 DECL_FUNCTION_VERSIONED (olddecl) = 1;
1162 if (DECL_ASSEMBLER_NAME_SET_P (olddecl))
1163 mangle_decl (olddecl);
1164 }
1165
1166 if (!DECL_FUNCTION_VERSIONED (newdecl))
1167 {
1168 DECL_FUNCTION_VERSIONED (newdecl) = 1;
1169 if (DECL_ASSEMBLER_NAME_SET_P (newdecl))
1170 mangle_decl (newdecl);
1171 }
1172
1173 if (record)
1174 cgraph_node::record_function_versions (olddecl, newdecl);
1175
1176 return true;
1177 }
1178
1179 /* If NEWDECL is `static' and an `extern' was seen previously,
1180 warn about it. OLDDECL is the previous declaration.
1181
1182 Note that this does not apply to the C++ case of declaring
1183 a variable `extern const' and then later `const'.
1184
1185 Don't complain about built-in functions, since they are beyond
1186 the user's control. */
1187
1188 void
warn_extern_redeclared_static(tree newdecl,tree olddecl)1189 warn_extern_redeclared_static (tree newdecl, tree olddecl)
1190 {
1191 if (TREE_CODE (newdecl) == TYPE_DECL
1192 || TREE_CODE (newdecl) == TEMPLATE_DECL
1193 || TREE_CODE (newdecl) == CONST_DECL
1194 || TREE_CODE (newdecl) == NAMESPACE_DECL)
1195 return;
1196
1197 /* Don't get confused by static member functions; that's a different
1198 use of `static'. */
1199 if (TREE_CODE (newdecl) == FUNCTION_DECL
1200 && DECL_STATIC_FUNCTION_P (newdecl))
1201 return;
1202
1203 /* If the old declaration was `static', or the new one isn't, then
1204 everything is OK. */
1205 if (DECL_THIS_STATIC (olddecl) || !DECL_THIS_STATIC (newdecl))
1206 return;
1207
1208 /* It's OK to declare a builtin function as `static'. */
1209 if (TREE_CODE (olddecl) == FUNCTION_DECL
1210 && DECL_ARTIFICIAL (olddecl))
1211 return;
1212
1213 if (permerror (DECL_SOURCE_LOCATION (newdecl),
1214 "%qD was declared %<extern%> and later %<static%>", newdecl))
1215 inform (DECL_SOURCE_LOCATION (olddecl),
1216 "previous declaration of %qD", olddecl);
1217 }
1218
1219 /* NEW_DECL is a redeclaration of OLD_DECL; both are functions or
1220 function templates. If their exception specifications do not
1221 match, issue a diagnostic. */
1222
1223 static void
check_redeclaration_exception_specification(tree new_decl,tree old_decl)1224 check_redeclaration_exception_specification (tree new_decl,
1225 tree old_decl)
1226 {
1227 tree new_exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (new_decl));
1228 tree old_exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (old_decl));
1229
1230 /* Two default specs are equivalent, don't force evaluation. */
1231 if (UNEVALUATED_NOEXCEPT_SPEC_P (new_exceptions)
1232 && UNEVALUATED_NOEXCEPT_SPEC_P (old_exceptions))
1233 return;
1234
1235 if (!type_dependent_expression_p (old_decl))
1236 {
1237 maybe_instantiate_noexcept (new_decl);
1238 maybe_instantiate_noexcept (old_decl);
1239 }
1240 new_exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (new_decl));
1241 old_exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (old_decl));
1242
1243 /* [except.spec]
1244
1245 If any declaration of a function has an exception-specification,
1246 all declarations, including the definition and an explicit
1247 specialization, of that function shall have an
1248 exception-specification with the same set of type-ids. */
1249 if (! DECL_IS_BUILTIN (old_decl)
1250 && !comp_except_specs (new_exceptions, old_exceptions, ce_normal))
1251 {
1252 const char *const msg
1253 = G_("declaration of %qF has a different exception specifier");
1254 bool complained = true;
1255 location_t new_loc = DECL_SOURCE_LOCATION (new_decl);
1256 if (DECL_IN_SYSTEM_HEADER (old_decl))
1257 complained = pedwarn (new_loc, OPT_Wsystem_headers, msg, new_decl);
1258 else if (!flag_exceptions)
1259 /* We used to silently permit mismatched eh specs with
1260 -fno-exceptions, so make them a pedwarn now. */
1261 complained = pedwarn (new_loc, OPT_Wpedantic, msg, new_decl);
1262 else
1263 error_at (new_loc, msg, new_decl);
1264 if (complained)
1265 inform (DECL_SOURCE_LOCATION (old_decl),
1266 "from previous declaration %qF", old_decl);
1267 }
1268 }
1269
1270 /* Return true if OLD_DECL and NEW_DECL agree on constexprness.
1271 Otherwise issue diagnostics. */
1272
1273 static bool
validate_constexpr_redeclaration(tree old_decl,tree new_decl)1274 validate_constexpr_redeclaration (tree old_decl, tree new_decl)
1275 {
1276 old_decl = STRIP_TEMPLATE (old_decl);
1277 new_decl = STRIP_TEMPLATE (new_decl);
1278 if (!VAR_OR_FUNCTION_DECL_P (old_decl)
1279 || !VAR_OR_FUNCTION_DECL_P (new_decl))
1280 return true;
1281 if (DECL_DECLARED_CONSTEXPR_P (old_decl)
1282 == DECL_DECLARED_CONSTEXPR_P (new_decl))
1283 return true;
1284 if (TREE_CODE (old_decl) == FUNCTION_DECL)
1285 {
1286 if (DECL_BUILT_IN (old_decl))
1287 {
1288 /* Hide a built-in declaration. */
1289 DECL_DECLARED_CONSTEXPR_P (old_decl)
1290 = DECL_DECLARED_CONSTEXPR_P (new_decl);
1291 return true;
1292 }
1293 /* 7.1.5 [dcl.constexpr]
1294 Note: An explicit specialization can differ from the template
1295 declaration with respect to the constexpr specifier. */
1296 if (! DECL_TEMPLATE_SPECIALIZATION (old_decl)
1297 && DECL_TEMPLATE_SPECIALIZATION (new_decl))
1298 return true;
1299
1300 error_at (DECL_SOURCE_LOCATION (new_decl),
1301 "redeclaration %qD differs in %<constexpr%> "
1302 "from previous declaration", new_decl);
1303 inform (DECL_SOURCE_LOCATION (old_decl),
1304 "previous declaration %qD", old_decl);
1305 return false;
1306 }
1307 return true;
1308 }
1309
1310 // If OLDDECL and NEWDECL are concept declarations with the same type
1311 // (i.e., and template parameters), but different requirements,
1312 // emit diagnostics and return true. Otherwise, return false.
1313 static inline bool
check_concept_refinement(tree olddecl,tree newdecl)1314 check_concept_refinement (tree olddecl, tree newdecl)
1315 {
1316 if (!DECL_DECLARED_CONCEPT_P (olddecl) || !DECL_DECLARED_CONCEPT_P (newdecl))
1317 return false;
1318
1319 tree d1 = DECL_TEMPLATE_RESULT (olddecl);
1320 tree d2 = DECL_TEMPLATE_RESULT (newdecl);
1321 if (TREE_CODE (d1) != TREE_CODE (d2))
1322 return false;
1323
1324 tree t1 = TREE_TYPE (d1);
1325 tree t2 = TREE_TYPE (d2);
1326 if (TREE_CODE (d1) == FUNCTION_DECL)
1327 {
1328 if (compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2))
1329 && comp_template_parms (DECL_TEMPLATE_PARMS (olddecl),
1330 DECL_TEMPLATE_PARMS (newdecl))
1331 && !equivalently_constrained (olddecl, newdecl))
1332 {
1333 error ("cannot specialize concept %q#D", olddecl);
1334 return true;
1335 }
1336 }
1337 return false;
1338 }
1339
1340 /* DECL is a redeclaration of a function or function template. If
1341 it does have default arguments issue a diagnostic. Note: this
1342 function is used to enforce the requirements in C++11 8.3.6 about
1343 no default arguments in redeclarations. */
1344
1345 static void
check_redeclaration_no_default_args(tree decl)1346 check_redeclaration_no_default_args (tree decl)
1347 {
1348 gcc_assert (DECL_DECLARES_FUNCTION_P (decl));
1349
1350 for (tree t = FUNCTION_FIRST_USER_PARMTYPE (decl);
1351 t && t != void_list_node; t = TREE_CHAIN (t))
1352 if (TREE_PURPOSE (t))
1353 {
1354 permerror (DECL_SOURCE_LOCATION (decl),
1355 "redeclaration of %q#D may not have default "
1356 "arguments", decl);
1357 return;
1358 }
1359 }
1360
1361 /* Merge tree bits that correspond to attributes noreturn, nothrow,
1362 const, malloc, and pure from NEWDECL with those of OLDDECL. */
1363
1364 static void
merge_attribute_bits(tree newdecl,tree olddecl)1365 merge_attribute_bits (tree newdecl, tree olddecl)
1366 {
1367 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1368 TREE_THIS_VOLATILE (olddecl) |= TREE_THIS_VOLATILE (newdecl);
1369 TREE_NOTHROW (newdecl) |= TREE_NOTHROW (olddecl);
1370 TREE_NOTHROW (olddecl) |= TREE_NOTHROW (newdecl);
1371 TREE_READONLY (newdecl) |= TREE_READONLY (olddecl);
1372 TREE_READONLY (olddecl) |= TREE_READONLY (newdecl);
1373 DECL_IS_MALLOC (newdecl) |= DECL_IS_MALLOC (olddecl);
1374 DECL_IS_MALLOC (olddecl) |= DECL_IS_MALLOC (newdecl);
1375 DECL_PURE_P (newdecl) |= DECL_PURE_P (olddecl);
1376 DECL_PURE_P (olddecl) |= DECL_PURE_P (newdecl);
1377 DECL_UNINLINABLE (newdecl) |= DECL_UNINLINABLE (olddecl);
1378 DECL_UNINLINABLE (olddecl) |= DECL_UNINLINABLE (newdecl);
1379 }
1380
1381 #define GNU_INLINE_P(fn) (DECL_DECLARED_INLINE_P (fn) \
1382 && lookup_attribute ("gnu_inline", \
1383 DECL_ATTRIBUTES (fn)))
1384
1385 /* If NEWDECL is a redeclaration of OLDDECL, merge the declarations.
1386 If the redeclaration is invalid, a diagnostic is issued, and the
1387 error_mark_node is returned. Otherwise, OLDDECL is returned.
1388
1389 If NEWDECL is not a redeclaration of OLDDECL, NULL_TREE is
1390 returned.
1391
1392 NEWDECL_IS_FRIEND is true if NEWDECL was declared as a friend. */
1393
1394 tree
duplicate_decls(tree newdecl,tree olddecl,bool newdecl_is_friend)1395 duplicate_decls (tree newdecl, tree olddecl, bool newdecl_is_friend)
1396 {
1397 unsigned olddecl_uid = DECL_UID (olddecl);
1398 int olddecl_friend = 0, types_match = 0, hidden_friend = 0;
1399 int new_defines_function = 0;
1400 tree new_template_info;
1401
1402 if (newdecl == olddecl)
1403 return olddecl;
1404
1405 types_match = decls_match (newdecl, olddecl);
1406
1407 /* If either the type of the new decl or the type of the old decl is an
1408 error_mark_node, then that implies that we have already issued an
1409 error (earlier) for some bogus type specification, and in that case,
1410 it is rather pointless to harass the user with yet more error message
1411 about the same declaration, so just pretend the types match here. */
1412 if (TREE_TYPE (newdecl) == error_mark_node
1413 || TREE_TYPE (olddecl) == error_mark_node)
1414 return error_mark_node;
1415
1416 if (DECL_NAME (newdecl)
1417 && DECL_NAME (olddecl)
1418 && UDLIT_OPER_P (DECL_NAME (newdecl))
1419 && UDLIT_OPER_P (DECL_NAME (olddecl)))
1420 {
1421 if (TREE_CODE (newdecl) == TEMPLATE_DECL
1422 && TREE_CODE (olddecl) != TEMPLATE_DECL
1423 && check_raw_literal_operator (olddecl))
1424 error ("literal operator template %q+D conflicts with"
1425 " raw literal operator %qD", newdecl, olddecl);
1426 else if (TREE_CODE (newdecl) != TEMPLATE_DECL
1427 && TREE_CODE (olddecl) == TEMPLATE_DECL
1428 && check_raw_literal_operator (newdecl))
1429 error ("raw literal operator %q+D conflicts with"
1430 " literal operator template %qD", newdecl, olddecl);
1431 }
1432
1433 /* True to merge attributes between the declarations, false to
1434 set OLDDECL's attributes to those of NEWDECL (for template
1435 explicit specializations that specify their own attributes
1436 independent of those specified for the primary template). */
1437 const bool merge_attr = (TREE_CODE (newdecl) != FUNCTION_DECL
1438 || !DECL_TEMPLATE_SPECIALIZATION (newdecl)
1439 || DECL_TEMPLATE_SPECIALIZATION (olddecl));
1440
1441 if (DECL_P (olddecl)
1442 && TREE_CODE (newdecl) == FUNCTION_DECL
1443 && TREE_CODE (olddecl) == FUNCTION_DECL
1444 && merge_attr
1445 && diagnose_mismatched_attributes (olddecl, newdecl))
1446 {
1447 if (DECL_INITIAL (olddecl))
1448 inform (DECL_SOURCE_LOCATION (olddecl),
1449 "previous definition of %qD was here", olddecl);
1450 else
1451 inform (DECL_SOURCE_LOCATION (olddecl),
1452 "previous declaration of %qD was here", olddecl);
1453 }
1454
1455 /* Check for redeclaration and other discrepancies. */
1456 if (TREE_CODE (olddecl) == FUNCTION_DECL
1457 && DECL_ARTIFICIAL (olddecl))
1458 {
1459 gcc_assert (!DECL_HIDDEN_FRIEND_P (olddecl));
1460 if (TREE_CODE (newdecl) != FUNCTION_DECL)
1461 {
1462 /* Avoid warnings redeclaring built-ins which have not been
1463 explicitly declared. */
1464 if (DECL_ANTICIPATED (olddecl))
1465 {
1466 if (TREE_PUBLIC (newdecl)
1467 && CP_DECL_CONTEXT (newdecl) == global_namespace)
1468 warning_at (DECL_SOURCE_LOCATION (newdecl),
1469 OPT_Wbuiltin_declaration_mismatch,
1470 "built-in function %qD declared as non-function",
1471 newdecl);
1472 return NULL_TREE;
1473 }
1474
1475 /* If you declare a built-in or predefined function name as static,
1476 the old definition is overridden, but optionally warn this was a
1477 bad choice of name. */
1478 if (! TREE_PUBLIC (newdecl))
1479 {
1480 warning (OPT_Wshadow,
1481 DECL_BUILT_IN (olddecl)
1482 ? G_("shadowing built-in function %q#D")
1483 : G_("shadowing library function %q#D"), olddecl);
1484 /* Discard the old built-in function. */
1485 return NULL_TREE;
1486 }
1487 /* If the built-in is not ansi, then programs can override
1488 it even globally without an error. */
1489 else if (! DECL_BUILT_IN (olddecl))
1490 warning_at (DECL_SOURCE_LOCATION (newdecl), 0,
1491 "library function %q#D redeclared as non-function %q#D",
1492 olddecl, newdecl);
1493 else
1494 error ("declaration of %q+#D conflicts with built-in "
1495 "declaration %q#D", newdecl, olddecl);
1496 return NULL_TREE;
1497 }
1498 else if (DECL_OMP_DECLARE_REDUCTION_P (olddecl))
1499 {
1500 gcc_assert (DECL_OMP_DECLARE_REDUCTION_P (newdecl));
1501 error_at (DECL_SOURCE_LOCATION (newdecl),
1502 "redeclaration of %<pragma omp declare reduction%>");
1503 inform (DECL_SOURCE_LOCATION (olddecl),
1504 "previous %<pragma omp declare reduction%> declaration");
1505 return error_mark_node;
1506 }
1507 else if (!types_match)
1508 {
1509 /* Avoid warnings redeclaring built-ins which have not been
1510 explicitly declared. */
1511 if (DECL_ANTICIPATED (olddecl))
1512 {
1513 tree t1, t2;
1514
1515 /* A new declaration doesn't match a built-in one unless it
1516 is also extern "C". */
1517 gcc_assert (DECL_IS_BUILTIN (olddecl));
1518 gcc_assert (DECL_EXTERN_C_P (olddecl));
1519 if (!DECL_EXTERN_C_P (newdecl))
1520 return NULL_TREE;
1521
1522 for (t1 = TYPE_ARG_TYPES (TREE_TYPE (newdecl)),
1523 t2 = TYPE_ARG_TYPES (TREE_TYPE (olddecl));
1524 t1 || t2;
1525 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1526 {
1527 if (!t1 || !t2)
1528 break;
1529 /* FILE, tm types are not known at the time
1530 we create the builtins. */
1531 for (unsigned i = 0;
1532 i < sizeof (builtin_structptr_types)
1533 / sizeof (builtin_structptr_type);
1534 ++i)
1535 if (TREE_VALUE (t2) == builtin_structptr_types[i].node)
1536 {
1537 tree t = TREE_VALUE (t1);
1538
1539 if (TYPE_PTR_P (t)
1540 && TYPE_IDENTIFIER (TREE_TYPE (t))
1541 == get_identifier (builtin_structptr_types[i].str)
1542 && compparms (TREE_CHAIN (t1), TREE_CHAIN (t2)))
1543 {
1544 tree oldargs = TYPE_ARG_TYPES (TREE_TYPE (olddecl));
1545
1546 TYPE_ARG_TYPES (TREE_TYPE (olddecl))
1547 = TYPE_ARG_TYPES (TREE_TYPE (newdecl));
1548 types_match = decls_match (newdecl, olddecl);
1549 if (types_match)
1550 return duplicate_decls (newdecl, olddecl,
1551 newdecl_is_friend);
1552 TYPE_ARG_TYPES (TREE_TYPE (olddecl)) = oldargs;
1553 }
1554 goto next_arg;
1555 }
1556
1557 if (! same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1558 break;
1559 next_arg:;
1560 }
1561
1562 warning_at (DECL_SOURCE_LOCATION (newdecl),
1563 OPT_Wbuiltin_declaration_mismatch,
1564 "declaration of %q#D conflicts with built-in "
1565 "declaration %q#D", newdecl, olddecl);
1566 }
1567 else if ((DECL_EXTERN_C_P (newdecl)
1568 && DECL_EXTERN_C_P (olddecl))
1569 || compparms (TYPE_ARG_TYPES (TREE_TYPE (newdecl)),
1570 TYPE_ARG_TYPES (TREE_TYPE (olddecl))))
1571 {
1572 /* Don't really override olddecl for __* prefixed builtins
1573 except for __[^b]*_chk, the compiler might be using those
1574 explicitly. */
1575 if (DECL_BUILT_IN (olddecl))
1576 {
1577 tree id = DECL_NAME (olddecl);
1578 const char *name = IDENTIFIER_POINTER (id);
1579 size_t len;
1580
1581 if (name[0] == '_'
1582 && name[1] == '_'
1583 && (strncmp (name + 2, "builtin_",
1584 strlen ("builtin_")) == 0
1585 || (len = strlen (name)) <= strlen ("___chk")
1586 || memcmp (name + len - strlen ("_chk"),
1587 "_chk", strlen ("_chk") + 1) != 0))
1588 {
1589 if (DECL_INITIAL (newdecl))
1590 {
1591 error_at (DECL_SOURCE_LOCATION (newdecl),
1592 "definition of %q#D ambiguates built-in "
1593 "declaration %q#D", newdecl, olddecl);
1594 return error_mark_node;
1595 }
1596 if (permerror (DECL_SOURCE_LOCATION (newdecl),
1597 "new declaration %q#D ambiguates built-in"
1598 " declaration %q#D", newdecl, olddecl)
1599 && flag_permissive)
1600 inform (DECL_SOURCE_LOCATION (newdecl),
1601 "ignoring the %q#D declaration", newdecl);
1602 return flag_permissive ? olddecl : error_mark_node;
1603 }
1604 }
1605
1606 /* A near match; override the builtin. */
1607
1608 if (TREE_PUBLIC (newdecl))
1609 warning_at (DECL_SOURCE_LOCATION (newdecl),
1610 OPT_Wbuiltin_declaration_mismatch,
1611 "new declaration %q#D ambiguates built-in "
1612 "declaration %q#D", newdecl, olddecl);
1613 else
1614 warning (OPT_Wshadow,
1615 DECL_BUILT_IN (olddecl)
1616 ? G_("shadowing built-in function %q#D")
1617 : G_("shadowing library function %q#D"), olddecl);
1618 }
1619 else
1620 /* Discard the old built-in function. */
1621 return NULL_TREE;
1622
1623 /* Replace the old RTL to avoid problems with inlining. */
1624 COPY_DECL_RTL (newdecl, olddecl);
1625 }
1626 /* Even if the types match, prefer the new declarations type for
1627 built-ins which have not been explicitly declared, for
1628 exception lists, etc... */
1629 else if (DECL_IS_BUILTIN (olddecl))
1630 {
1631 tree type = TREE_TYPE (newdecl);
1632 tree attribs = (*targetm.merge_type_attributes)
1633 (TREE_TYPE (olddecl), type);
1634
1635 type = cp_build_type_attribute_variant (type, attribs);
1636 TREE_TYPE (newdecl) = TREE_TYPE (olddecl) = type;
1637 }
1638
1639 /* If a function is explicitly declared "throw ()", propagate that to
1640 the corresponding builtin. */
1641 if (DECL_BUILT_IN_CLASS (olddecl) == BUILT_IN_NORMAL
1642 && DECL_ANTICIPATED (olddecl)
1643 && TREE_NOTHROW (newdecl)
1644 && !TREE_NOTHROW (olddecl))
1645 {
1646 enum built_in_function fncode = DECL_FUNCTION_CODE (olddecl);
1647 tree tmpdecl = builtin_decl_explicit (fncode);
1648 if (tmpdecl && tmpdecl != olddecl && types_match)
1649 TREE_NOTHROW (tmpdecl) = 1;
1650 }
1651
1652 /* Whether or not the builtin can throw exceptions has no
1653 bearing on this declarator. */
1654 TREE_NOTHROW (olddecl) = 0;
1655
1656 if (DECL_THIS_STATIC (newdecl) && !DECL_THIS_STATIC (olddecl))
1657 {
1658 /* If a builtin function is redeclared as `static', merge
1659 the declarations, but make the original one static. */
1660 DECL_THIS_STATIC (olddecl) = 1;
1661 TREE_PUBLIC (olddecl) = 0;
1662
1663 /* Make the old declaration consistent with the new one so
1664 that all remnants of the builtin-ness of this function
1665 will be banished. */
1666 SET_DECL_LANGUAGE (olddecl, DECL_LANGUAGE (newdecl));
1667 COPY_DECL_RTL (newdecl, olddecl);
1668 }
1669 }
1670 else if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
1671 {
1672 /* C++ Standard, 3.3, clause 4:
1673 "[Note: a namespace name or a class template name must be unique
1674 in its declarative region (7.3.2, clause 14). ]" */
1675 if (TREE_CODE (olddecl) != NAMESPACE_DECL
1676 && TREE_CODE (newdecl) != NAMESPACE_DECL
1677 && (TREE_CODE (olddecl) != TEMPLATE_DECL
1678 || TREE_CODE (DECL_TEMPLATE_RESULT (olddecl)) != TYPE_DECL)
1679 && (TREE_CODE (newdecl) != TEMPLATE_DECL
1680 || TREE_CODE (DECL_TEMPLATE_RESULT (newdecl)) != TYPE_DECL))
1681 {
1682 if ((TREE_CODE (olddecl) == TYPE_DECL && DECL_ARTIFICIAL (olddecl)
1683 && TREE_CODE (newdecl) != TYPE_DECL)
1684 || (TREE_CODE (newdecl) == TYPE_DECL && DECL_ARTIFICIAL (newdecl)
1685 && TREE_CODE (olddecl) != TYPE_DECL))
1686 {
1687 /* We do nothing special here, because C++ does such nasty
1688 things with TYPE_DECLs. Instead, just let the TYPE_DECL
1689 get shadowed, and know that if we need to find a TYPE_DECL
1690 for a given name, we can look in the IDENTIFIER_TYPE_VALUE
1691 slot of the identifier. */
1692 return NULL_TREE;
1693 }
1694
1695 if ((TREE_CODE (newdecl) == FUNCTION_DECL
1696 && DECL_FUNCTION_TEMPLATE_P (olddecl))
1697 || (TREE_CODE (olddecl) == FUNCTION_DECL
1698 && DECL_FUNCTION_TEMPLATE_P (newdecl)))
1699 return NULL_TREE;
1700 }
1701
1702 error ("%q#D redeclared as different kind of symbol", newdecl);
1703 if (TREE_CODE (olddecl) == TREE_LIST)
1704 olddecl = TREE_VALUE (olddecl);
1705 inform (DECL_SOURCE_LOCATION (olddecl),
1706 "previous declaration %q#D", olddecl);
1707
1708 return error_mark_node;
1709 }
1710 else if (!types_match)
1711 {
1712 if (CP_DECL_CONTEXT (newdecl) != CP_DECL_CONTEXT (olddecl))
1713 /* These are certainly not duplicate declarations; they're
1714 from different scopes. */
1715 return NULL_TREE;
1716
1717 if (TREE_CODE (newdecl) == TEMPLATE_DECL)
1718 {
1719 /* The name of a class template may not be declared to refer to
1720 any other template, class, function, object, namespace, value,
1721 or type in the same scope. */
1722 if (TREE_CODE (DECL_TEMPLATE_RESULT (olddecl)) == TYPE_DECL
1723 || TREE_CODE (DECL_TEMPLATE_RESULT (newdecl)) == TYPE_DECL)
1724 {
1725 error ("conflicting declaration of template %q+#D", newdecl);
1726 inform (DECL_SOURCE_LOCATION (olddecl),
1727 "previous declaration %q#D", olddecl);
1728 return error_mark_node;
1729 }
1730 else if (TREE_CODE (DECL_TEMPLATE_RESULT (olddecl)) == FUNCTION_DECL
1731 && TREE_CODE (DECL_TEMPLATE_RESULT (newdecl)) == FUNCTION_DECL
1732 && compparms (TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (olddecl))),
1733 TYPE_ARG_TYPES (TREE_TYPE (DECL_TEMPLATE_RESULT (newdecl))))
1734 && comp_template_parms (DECL_TEMPLATE_PARMS (newdecl),
1735 DECL_TEMPLATE_PARMS (olddecl))
1736 /* Template functions can be disambiguated by
1737 return type. */
1738 && same_type_p (TREE_TYPE (TREE_TYPE (newdecl)),
1739 TREE_TYPE (TREE_TYPE (olddecl)))
1740 // Template functions can also be disambiguated by
1741 // constraints.
1742 && equivalently_constrained (olddecl, newdecl))
1743 {
1744 error ("ambiguating new declaration %q+#D", newdecl);
1745 inform (DECL_SOURCE_LOCATION (olddecl),
1746 "old declaration %q#D", olddecl);
1747 }
1748 else if (check_concept_refinement (olddecl, newdecl))
1749 return error_mark_node;
1750 return NULL_TREE;
1751 }
1752 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1753 {
1754 if (DECL_EXTERN_C_P (newdecl) && DECL_EXTERN_C_P (olddecl))
1755 {
1756 error ("conflicting declaration of C function %q+#D",
1757 newdecl);
1758 inform (DECL_SOURCE_LOCATION (olddecl),
1759 "previous declaration %q#D", olddecl);
1760 return NULL_TREE;
1761 }
1762 /* For function versions, params and types match, but they
1763 are not ambiguous. */
1764 else if ((!DECL_FUNCTION_VERSIONED (newdecl)
1765 && !DECL_FUNCTION_VERSIONED (olddecl))
1766 // The functions have the same parameter types.
1767 && compparms (TYPE_ARG_TYPES (TREE_TYPE (newdecl)),
1768 TYPE_ARG_TYPES (TREE_TYPE (olddecl)))
1769 // And the same constraints.
1770 && equivalently_constrained (newdecl, olddecl))
1771 {
1772 error ("ambiguating new declaration of %q+#D", newdecl);
1773 inform (DECL_SOURCE_LOCATION (olddecl),
1774 "old declaration %q#D", olddecl);
1775 return error_mark_node;
1776 }
1777 else
1778 return NULL_TREE;
1779 }
1780 else
1781 {
1782 error ("conflicting declaration %q+#D", newdecl);
1783 inform (DECL_SOURCE_LOCATION (olddecl),
1784 "previous declaration as %q#D", olddecl);
1785 return error_mark_node;
1786 }
1787 }
1788 else if (TREE_CODE (newdecl) == FUNCTION_DECL
1789 && ((DECL_TEMPLATE_SPECIALIZATION (olddecl)
1790 && (!DECL_TEMPLATE_INFO (newdecl)
1791 || (DECL_TI_TEMPLATE (newdecl)
1792 != DECL_TI_TEMPLATE (olddecl))))
1793 || (DECL_TEMPLATE_SPECIALIZATION (newdecl)
1794 && (!DECL_TEMPLATE_INFO (olddecl)
1795 || (DECL_TI_TEMPLATE (olddecl)
1796 != DECL_TI_TEMPLATE (newdecl))))))
1797 /* It's OK to have a template specialization and a non-template
1798 with the same type, or to have specializations of two
1799 different templates with the same type. Note that if one is a
1800 specialization, and the other is an instantiation of the same
1801 template, that we do not exit at this point. That situation
1802 can occur if we instantiate a template class, and then
1803 specialize one of its methods. This situation is valid, but
1804 the declarations must be merged in the usual way. */
1805 return NULL_TREE;
1806 else if (TREE_CODE (newdecl) == FUNCTION_DECL
1807 && ((DECL_TEMPLATE_INSTANTIATION (olddecl)
1808 && !DECL_USE_TEMPLATE (newdecl))
1809 || (DECL_TEMPLATE_INSTANTIATION (newdecl)
1810 && !DECL_USE_TEMPLATE (olddecl))))
1811 /* One of the declarations is a template instantiation, and the
1812 other is not a template at all. That's OK. */
1813 return NULL_TREE;
1814 else if (TREE_CODE (newdecl) == NAMESPACE_DECL)
1815 {
1816 /* In [namespace.alias] we have:
1817
1818 In a declarative region, a namespace-alias-definition can be
1819 used to redefine a namespace-alias declared in that declarative
1820 region to refer only to the namespace to which it already
1821 refers.
1822
1823 Therefore, if we encounter a second alias directive for the same
1824 alias, we can just ignore the second directive. */
1825 if (DECL_NAMESPACE_ALIAS (newdecl)
1826 && (DECL_NAMESPACE_ALIAS (newdecl)
1827 == DECL_NAMESPACE_ALIAS (olddecl)))
1828 return olddecl;
1829
1830 /* Leave it to update_binding to merge or report error. */
1831 return NULL_TREE;
1832 }
1833 else
1834 {
1835 const char *errmsg = redeclaration_error_message (newdecl, olddecl);
1836 if (errmsg)
1837 {
1838 error_at (DECL_SOURCE_LOCATION (newdecl), errmsg, newdecl);
1839 if (DECL_NAME (olddecl) != NULL_TREE)
1840 inform (DECL_SOURCE_LOCATION (olddecl),
1841 (DECL_INITIAL (olddecl) && namespace_bindings_p ())
1842 ? G_("%q#D previously defined here")
1843 : G_("%q#D previously declared here"), olddecl);
1844 return error_mark_node;
1845 }
1846 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1847 && DECL_INITIAL (olddecl) != NULL_TREE
1848 && !prototype_p (TREE_TYPE (olddecl))
1849 && prototype_p (TREE_TYPE (newdecl)))
1850 {
1851 /* Prototype decl follows defn w/o prototype. */
1852 if (warning_at (DECL_SOURCE_LOCATION (newdecl), 0,
1853 "prototype specified for %q#D", newdecl))
1854 inform (DECL_SOURCE_LOCATION (olddecl),
1855 "previous non-prototype definition here");
1856 }
1857 else if (VAR_OR_FUNCTION_DECL_P (olddecl)
1858 && DECL_LANGUAGE (newdecl) != DECL_LANGUAGE (olddecl))
1859 {
1860 /* [dcl.link]
1861 If two declarations of the same function or object
1862 specify different linkage-specifications ..., the program
1863 is ill-formed.... Except for functions with C++ linkage,
1864 a function declaration without a linkage specification
1865 shall not precede the first linkage specification for
1866 that function. A function can be declared without a
1867 linkage specification after an explicit linkage
1868 specification has been seen; the linkage explicitly
1869 specified in the earlier declaration is not affected by
1870 such a function declaration.
1871
1872 DR 563 raises the question why the restrictions on
1873 functions should not also apply to objects. Older
1874 versions of G++ silently ignore the linkage-specification
1875 for this example:
1876
1877 namespace N {
1878 extern int i;
1879 extern "C" int i;
1880 }
1881
1882 which is clearly wrong. Therefore, we now treat objects
1883 like functions. */
1884 if (current_lang_depth () == 0)
1885 {
1886 /* There is no explicit linkage-specification, so we use
1887 the linkage from the previous declaration. */
1888 retrofit_lang_decl (newdecl);
1889 SET_DECL_LANGUAGE (newdecl, DECL_LANGUAGE (olddecl));
1890 }
1891 else
1892 {
1893 error ("conflicting declaration of %q+#D with %qL linkage",
1894 newdecl, DECL_LANGUAGE (newdecl));
1895 inform (DECL_SOURCE_LOCATION (olddecl),
1896 "previous declaration with %qL linkage",
1897 DECL_LANGUAGE (olddecl));
1898 }
1899 }
1900
1901 if (DECL_LANG_SPECIFIC (olddecl) && DECL_USE_TEMPLATE (olddecl))
1902 ;
1903 else if (TREE_CODE (olddecl) == FUNCTION_DECL)
1904 {
1905 /* Note: free functions, as TEMPLATE_DECLs, are handled below. */
1906 if (DECL_FUNCTION_MEMBER_P (olddecl)
1907 && (/* grokfndecl passes member function templates too
1908 as FUNCTION_DECLs. */
1909 DECL_TEMPLATE_INFO (olddecl)
1910 /* C++11 8.3.6/6.
1911 Default arguments for a member function of a class
1912 template shall be specified on the initial declaration
1913 of the member function within the class template. */
1914 || CLASSTYPE_TEMPLATE_INFO (CP_DECL_CONTEXT (olddecl))))
1915 check_redeclaration_no_default_args (newdecl);
1916 else
1917 {
1918 tree t1 = FUNCTION_FIRST_USER_PARMTYPE (olddecl);
1919 tree t2 = FUNCTION_FIRST_USER_PARMTYPE (newdecl);
1920 int i = 1;
1921
1922 for (; t1 && t1 != void_list_node;
1923 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2), i++)
1924 if (TREE_PURPOSE (t1) && TREE_PURPOSE (t2))
1925 {
1926 if (simple_cst_equal (TREE_PURPOSE (t1),
1927 TREE_PURPOSE (t2)) == 1)
1928 {
1929 if (permerror (input_location,
1930 "default argument given for parameter "
1931 "%d of %q#D", i, newdecl))
1932 inform (DECL_SOURCE_LOCATION (olddecl),
1933 "previous specification in %q#D here",
1934 olddecl);
1935 }
1936 else
1937 {
1938 error ("default argument given for parameter %d "
1939 "of %q#D", i, newdecl);
1940 inform (DECL_SOURCE_LOCATION (olddecl),
1941 "previous specification in %q#D here",
1942 olddecl);
1943 }
1944 }
1945 }
1946 }
1947 }
1948
1949 /* Do not merge an implicit typedef with an explicit one. In:
1950
1951 class A;
1952 ...
1953 typedef class A A __attribute__ ((foo));
1954
1955 the attribute should apply only to the typedef. */
1956 if (TREE_CODE (olddecl) == TYPE_DECL
1957 && (DECL_IMPLICIT_TYPEDEF_P (olddecl)
1958 || DECL_IMPLICIT_TYPEDEF_P (newdecl)))
1959 return NULL_TREE;
1960
1961 /* If new decl is `static' and an `extern' was seen previously,
1962 warn about it. */
1963 warn_extern_redeclared_static (newdecl, olddecl);
1964
1965 if (!validate_constexpr_redeclaration (olddecl, newdecl))
1966 return error_mark_node;
1967
1968 /* We have committed to returning 1 at this point. */
1969 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1970 {
1971 /* Now that functions must hold information normally held
1972 by field decls, there is extra work to do so that
1973 declaration information does not get destroyed during
1974 definition. */
1975 if (DECL_VINDEX (olddecl))
1976 DECL_VINDEX (newdecl) = DECL_VINDEX (olddecl);
1977 if (DECL_CONTEXT (olddecl))
1978 DECL_CONTEXT (newdecl) = DECL_CONTEXT (olddecl);
1979 DECL_STATIC_CONSTRUCTOR (newdecl) |= DECL_STATIC_CONSTRUCTOR (olddecl);
1980 DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
1981 DECL_PURE_VIRTUAL_P (newdecl) |= DECL_PURE_VIRTUAL_P (olddecl);
1982 DECL_VIRTUAL_P (newdecl) |= DECL_VIRTUAL_P (olddecl);
1983 DECL_INVALID_OVERRIDER_P (newdecl) |= DECL_INVALID_OVERRIDER_P (olddecl);
1984 DECL_FINAL_P (newdecl) |= DECL_FINAL_P (olddecl);
1985 DECL_OVERRIDE_P (newdecl) |= DECL_OVERRIDE_P (olddecl);
1986 DECL_THIS_STATIC (newdecl) |= DECL_THIS_STATIC (olddecl);
1987 if (DECL_OVERLOADED_OPERATOR_P (olddecl))
1988 DECL_OVERLOADED_OPERATOR_CODE_RAW (newdecl)
1989 = DECL_OVERLOADED_OPERATOR_CODE_RAW (olddecl);
1990 new_defines_function = DECL_INITIAL (newdecl) != NULL_TREE;
1991
1992 /* Optionally warn about more than one declaration for the same
1993 name, but don't warn about a function declaration followed by a
1994 definition. */
1995 if (warn_redundant_decls && ! DECL_ARTIFICIAL (olddecl)
1996 && !(new_defines_function && DECL_INITIAL (olddecl) == NULL_TREE)
1997 /* Don't warn about extern decl followed by definition. */
1998 && !(DECL_EXTERNAL (olddecl) && ! DECL_EXTERNAL (newdecl))
1999 /* Don't warn about friends, let add_friend take care of it. */
2000 && ! (newdecl_is_friend || DECL_FRIEND_P (olddecl))
2001 /* Don't warn about declaration followed by specialization. */
2002 && (! DECL_TEMPLATE_SPECIALIZATION (newdecl)
2003 || DECL_TEMPLATE_SPECIALIZATION (olddecl)))
2004 {
2005 if (warning_at (DECL_SOURCE_LOCATION (newdecl),
2006 OPT_Wredundant_decls,
2007 "redundant redeclaration of %qD in same scope",
2008 newdecl))
2009 inform (DECL_SOURCE_LOCATION (olddecl),
2010 "previous declaration of %qD", olddecl);
2011 }
2012
2013 if (!(DECL_TEMPLATE_INSTANTIATION (olddecl)
2014 && DECL_TEMPLATE_SPECIALIZATION (newdecl)))
2015 {
2016 if (DECL_DELETED_FN (newdecl))
2017 {
2018 error ("deleted definition of %q+D", newdecl);
2019 inform (DECL_SOURCE_LOCATION (olddecl),
2020 "previous declaration of %qD", olddecl);
2021 }
2022 DECL_DELETED_FN (newdecl) |= DECL_DELETED_FN (olddecl);
2023 }
2024 }
2025
2026 /* Deal with C++: must preserve virtual function table size. */
2027 if (TREE_CODE (olddecl) == TYPE_DECL)
2028 {
2029 tree newtype = TREE_TYPE (newdecl);
2030 tree oldtype = TREE_TYPE (olddecl);
2031
2032 if (newtype != error_mark_node && oldtype != error_mark_node
2033 && TYPE_LANG_SPECIFIC (newtype) && TYPE_LANG_SPECIFIC (oldtype))
2034 CLASSTYPE_FRIEND_CLASSES (newtype)
2035 = CLASSTYPE_FRIEND_CLASSES (oldtype);
2036
2037 DECL_ORIGINAL_TYPE (newdecl) = DECL_ORIGINAL_TYPE (olddecl);
2038 }
2039
2040 /* Copy all the DECL_... slots specified in the new decl except for
2041 any that we copy here from the old type. */
2042 if (merge_attr)
2043 DECL_ATTRIBUTES (newdecl)
2044 = (*targetm.merge_decl_attributes) (olddecl, newdecl);
2045 else
2046 DECL_ATTRIBUTES (olddecl) = DECL_ATTRIBUTES (newdecl);
2047
2048 if (DECL_DECLARES_FUNCTION_P (olddecl) && DECL_DECLARES_FUNCTION_P (newdecl))
2049 {
2050 olddecl_friend = DECL_FRIEND_P (olddecl);
2051 hidden_friend = (DECL_ANTICIPATED (olddecl)
2052 && DECL_HIDDEN_FRIEND_P (olddecl)
2053 && newdecl_is_friend);
2054 if (!hidden_friend)
2055 {
2056 DECL_ANTICIPATED (olddecl) = 0;
2057 DECL_HIDDEN_FRIEND_P (olddecl) = 0;
2058 }
2059 }
2060
2061 if (TREE_CODE (newdecl) == TEMPLATE_DECL)
2062 {
2063 tree old_result;
2064 tree new_result;
2065 old_result = DECL_TEMPLATE_RESULT (olddecl);
2066 new_result = DECL_TEMPLATE_RESULT (newdecl);
2067 TREE_TYPE (olddecl) = TREE_TYPE (old_result);
2068 DECL_TEMPLATE_SPECIALIZATIONS (olddecl)
2069 = chainon (DECL_TEMPLATE_SPECIALIZATIONS (olddecl),
2070 DECL_TEMPLATE_SPECIALIZATIONS (newdecl));
2071
2072 DECL_ATTRIBUTES (old_result)
2073 = (*targetm.merge_decl_attributes) (old_result, new_result);
2074
2075 if (DECL_FUNCTION_TEMPLATE_P (newdecl))
2076 {
2077 /* Per C++11 8.3.6/4, default arguments cannot be added in later
2078 declarations of a function template. */
2079 if (DECL_SOURCE_LOCATION (newdecl)
2080 != DECL_SOURCE_LOCATION (olddecl))
2081 check_redeclaration_no_default_args (newdecl);
2082
2083 check_default_args (newdecl);
2084
2085 if (GNU_INLINE_P (old_result) != GNU_INLINE_P (new_result)
2086 && DECL_INITIAL (new_result))
2087 {
2088 if (DECL_INITIAL (old_result))
2089 DECL_UNINLINABLE (old_result) = 1;
2090 else
2091 DECL_UNINLINABLE (old_result) = DECL_UNINLINABLE (new_result);
2092 DECL_EXTERNAL (old_result) = DECL_EXTERNAL (new_result);
2093 DECL_NOT_REALLY_EXTERN (old_result)
2094 = DECL_NOT_REALLY_EXTERN (new_result);
2095 DECL_INTERFACE_KNOWN (old_result)
2096 = DECL_INTERFACE_KNOWN (new_result);
2097 DECL_DECLARED_INLINE_P (old_result)
2098 = DECL_DECLARED_INLINE_P (new_result);
2099 DECL_DISREGARD_INLINE_LIMITS (old_result)
2100 |= DECL_DISREGARD_INLINE_LIMITS (new_result);
2101
2102 }
2103 else
2104 {
2105 DECL_DECLARED_INLINE_P (old_result)
2106 |= DECL_DECLARED_INLINE_P (new_result);
2107 DECL_DISREGARD_INLINE_LIMITS (old_result)
2108 |= DECL_DISREGARD_INLINE_LIMITS (new_result);
2109 check_redeclaration_exception_specification (newdecl, olddecl);
2110
2111 merge_attribute_bits (new_result, old_result);
2112 }
2113 }
2114
2115 /* If the new declaration is a definition, update the file and
2116 line information on the declaration, and also make
2117 the old declaration the same definition. */
2118 if (DECL_INITIAL (new_result) != NULL_TREE)
2119 {
2120 DECL_SOURCE_LOCATION (olddecl)
2121 = DECL_SOURCE_LOCATION (old_result)
2122 = DECL_SOURCE_LOCATION (newdecl);
2123 DECL_INITIAL (old_result) = DECL_INITIAL (new_result);
2124 if (DECL_FUNCTION_TEMPLATE_P (newdecl))
2125 {
2126 tree parm;
2127 DECL_ARGUMENTS (old_result)
2128 = DECL_ARGUMENTS (new_result);
2129 for (parm = DECL_ARGUMENTS (old_result); parm;
2130 parm = DECL_CHAIN (parm))
2131 DECL_CONTEXT (parm) = old_result;
2132 }
2133 }
2134
2135 return olddecl;
2136 }
2137
2138 if (types_match)
2139 {
2140 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2141 check_redeclaration_exception_specification (newdecl, olddecl);
2142
2143 /* Automatically handles default parameters. */
2144 tree oldtype = TREE_TYPE (olddecl);
2145 tree newtype;
2146
2147 /* For typedefs use the old type, as the new type's DECL_NAME points
2148 at newdecl, which will be ggc_freed. */
2149 if (TREE_CODE (newdecl) == TYPE_DECL)
2150 {
2151 /* But NEWTYPE might have an attribute, honor that. */
2152 tree tem = TREE_TYPE (newdecl);
2153 newtype = oldtype;
2154
2155 if (TYPE_USER_ALIGN (tem))
2156 {
2157 if (TYPE_ALIGN (tem) > TYPE_ALIGN (newtype))
2158 SET_TYPE_ALIGN (newtype, TYPE_ALIGN (tem));
2159 TYPE_USER_ALIGN (newtype) = true;
2160 }
2161
2162 /* And remove the new type from the variants list. */
2163 if (TYPE_NAME (TREE_TYPE (newdecl)) == newdecl)
2164 {
2165 tree remove = TREE_TYPE (newdecl);
2166 for (tree t = TYPE_MAIN_VARIANT (remove); ;
2167 t = TYPE_NEXT_VARIANT (t))
2168 if (TYPE_NEXT_VARIANT (t) == remove)
2169 {
2170 TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (remove);
2171 break;
2172 }
2173 }
2174 }
2175 else if (merge_attr)
2176 newtype = merge_types (TREE_TYPE (newdecl), TREE_TYPE (olddecl));
2177 else
2178 newtype = TREE_TYPE (newdecl);
2179
2180 if (VAR_P (newdecl))
2181 {
2182 DECL_THIS_EXTERN (newdecl) |= DECL_THIS_EXTERN (olddecl);
2183 /* For already initialized vars, TREE_READONLY could have been
2184 cleared in cp_finish_decl, because the var needs runtime
2185 initialization or destruction. Make sure not to set
2186 TREE_READONLY on it again. */
2187 if (DECL_INITIALIZED_P (olddecl)
2188 && !DECL_EXTERNAL (olddecl)
2189 && !TREE_READONLY (olddecl))
2190 TREE_READONLY (newdecl) = 0;
2191 DECL_INITIALIZED_P (newdecl) |= DECL_INITIALIZED_P (olddecl);
2192 DECL_NONTRIVIALLY_INITIALIZED_P (newdecl)
2193 |= DECL_NONTRIVIALLY_INITIALIZED_P (olddecl);
2194 if (DECL_DEPENDENT_INIT_P (olddecl))
2195 SET_DECL_DEPENDENT_INIT_P (newdecl, true);
2196 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (newdecl)
2197 |= DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (olddecl);
2198 if (DECL_CLASS_SCOPE_P (olddecl))
2199 DECL_DECLARED_CONSTEXPR_P (newdecl)
2200 |= DECL_DECLARED_CONSTEXPR_P (olddecl);
2201
2202 /* Merge the threadprivate attribute from OLDDECL into NEWDECL. */
2203 if (DECL_LANG_SPECIFIC (olddecl)
2204 && CP_DECL_THREADPRIVATE_P (olddecl))
2205 {
2206 /* Allocate a LANG_SPECIFIC structure for NEWDECL, if needed. */
2207 retrofit_lang_decl (newdecl);
2208 CP_DECL_THREADPRIVATE_P (newdecl) = 1;
2209 }
2210 }
2211
2212 /* An explicit specialization of a function template or of a member
2213 function of a class template can be declared transaction_safe
2214 independently of whether the corresponding template entity is declared
2215 transaction_safe. */
2216 if (flag_tm && TREE_CODE (newdecl) == FUNCTION_DECL
2217 && DECL_TEMPLATE_INSTANTIATION (olddecl)
2218 && DECL_TEMPLATE_SPECIALIZATION (newdecl)
2219 && tx_safe_fn_type_p (newtype)
2220 && !tx_safe_fn_type_p (TREE_TYPE (newdecl)))
2221 newtype = tx_unsafe_fn_variant (newtype);
2222
2223 TREE_TYPE (newdecl) = TREE_TYPE (olddecl) = newtype;
2224
2225 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2226 check_default_args (newdecl);
2227
2228 /* Lay the type out, unless already done. */
2229 if (! same_type_p (newtype, oldtype)
2230 && TREE_TYPE (newdecl) != error_mark_node
2231 && !(processing_template_decl && uses_template_parms (newdecl)))
2232 layout_type (TREE_TYPE (newdecl));
2233
2234 if ((VAR_P (newdecl)
2235 || TREE_CODE (newdecl) == PARM_DECL
2236 || TREE_CODE (newdecl) == RESULT_DECL
2237 || TREE_CODE (newdecl) == FIELD_DECL
2238 || TREE_CODE (newdecl) == TYPE_DECL)
2239 && !(processing_template_decl && uses_template_parms (newdecl)))
2240 layout_decl (newdecl, 0);
2241
2242 /* Merge deprecatedness. */
2243 if (TREE_DEPRECATED (newdecl))
2244 TREE_DEPRECATED (olddecl) = 1;
2245
2246 /* Preserve function specific target and optimization options */
2247 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2248 {
2249 if (DECL_FUNCTION_SPECIFIC_TARGET (olddecl)
2250 && !DECL_FUNCTION_SPECIFIC_TARGET (newdecl))
2251 DECL_FUNCTION_SPECIFIC_TARGET (newdecl)
2252 = DECL_FUNCTION_SPECIFIC_TARGET (olddecl);
2253
2254 if (DECL_FUNCTION_SPECIFIC_OPTIMIZATION (olddecl)
2255 && !DECL_FUNCTION_SPECIFIC_OPTIMIZATION (newdecl))
2256 DECL_FUNCTION_SPECIFIC_OPTIMIZATION (newdecl)
2257 = DECL_FUNCTION_SPECIFIC_OPTIMIZATION (olddecl);
2258 }
2259 else
2260 {
2261 /* Merge the const type qualifier. */
2262 if (TREE_READONLY (newdecl))
2263 TREE_READONLY (olddecl) = 1;
2264 /* Merge the volatile type qualifier. */
2265 if (TREE_THIS_VOLATILE (newdecl))
2266 TREE_THIS_VOLATILE (olddecl) = 1;
2267 }
2268
2269 /* Merge the initialization information. */
2270 if (DECL_INITIAL (newdecl) == NULL_TREE
2271 && DECL_INITIAL (olddecl) != NULL_TREE)
2272 {
2273 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
2274 DECL_SOURCE_LOCATION (newdecl) = DECL_SOURCE_LOCATION (olddecl);
2275 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2276 {
2277 DECL_SAVED_TREE (newdecl) = DECL_SAVED_TREE (olddecl);
2278 DECL_STRUCT_FUNCTION (newdecl) = DECL_STRUCT_FUNCTION (olddecl);
2279 }
2280 }
2281
2282 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2283 {
2284 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
2285 |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
2286 DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
2287 DECL_IS_OPERATOR_NEW (newdecl) |= DECL_IS_OPERATOR_NEW (olddecl);
2288 DECL_LOOPING_CONST_OR_PURE_P (newdecl)
2289 |= DECL_LOOPING_CONST_OR_PURE_P (olddecl);
2290
2291 if (merge_attr)
2292 merge_attribute_bits (newdecl, olddecl);
2293 else
2294 {
2295 /* Merge the noreturn bit. */
2296 TREE_THIS_VOLATILE (olddecl) = TREE_THIS_VOLATILE (newdecl);
2297 TREE_READONLY (olddecl) = TREE_READONLY (newdecl);
2298 TREE_NOTHROW (olddecl) = TREE_NOTHROW (newdecl);
2299 DECL_IS_MALLOC (olddecl) = DECL_IS_MALLOC (newdecl);
2300 DECL_PURE_P (olddecl) = DECL_PURE_P (newdecl);
2301 }
2302 /* Keep the old RTL. */
2303 COPY_DECL_RTL (olddecl, newdecl);
2304 }
2305 else if (VAR_P (newdecl)
2306 && (DECL_SIZE (olddecl) || !DECL_SIZE (newdecl)))
2307 {
2308 /* Keep the old RTL. We cannot keep the old RTL if the old
2309 declaration was for an incomplete object and the new
2310 declaration is not since many attributes of the RTL will
2311 change. */
2312 COPY_DECL_RTL (olddecl, newdecl);
2313 }
2314 }
2315 /* If cannot merge, then use the new type and qualifiers,
2316 and don't preserve the old rtl. */
2317 else
2318 {
2319 /* Clean out any memory we had of the old declaration. */
2320 tree oldstatic = value_member (olddecl, static_aggregates);
2321 if (oldstatic)
2322 TREE_VALUE (oldstatic) = error_mark_node;
2323
2324 TREE_TYPE (olddecl) = TREE_TYPE (newdecl);
2325 TREE_READONLY (olddecl) = TREE_READONLY (newdecl);
2326 TREE_THIS_VOLATILE (olddecl) = TREE_THIS_VOLATILE (newdecl);
2327 TREE_NOTHROW (olddecl) = TREE_NOTHROW (newdecl);
2328 TREE_SIDE_EFFECTS (olddecl) = TREE_SIDE_EFFECTS (newdecl);
2329 }
2330
2331 /* Merge the storage class information. */
2332 merge_weak (newdecl, olddecl);
2333
2334 DECL_DEFER_OUTPUT (newdecl) |= DECL_DEFER_OUTPUT (olddecl);
2335 TREE_PUBLIC (newdecl) = TREE_PUBLIC (olddecl);
2336 TREE_STATIC (olddecl) = TREE_STATIC (newdecl) |= TREE_STATIC (olddecl);
2337 if (! DECL_EXTERNAL (olddecl))
2338 DECL_EXTERNAL (newdecl) = 0;
2339 if (! DECL_COMDAT (olddecl))
2340 DECL_COMDAT (newdecl) = 0;
2341
2342 new_template_info = NULL_TREE;
2343 if (DECL_LANG_SPECIFIC (newdecl) && DECL_LANG_SPECIFIC (olddecl))
2344 {
2345 bool new_redefines_gnu_inline = false;
2346
2347 if (new_defines_function
2348 && ((DECL_INTERFACE_KNOWN (olddecl)
2349 && TREE_CODE (olddecl) == FUNCTION_DECL)
2350 || (TREE_CODE (olddecl) == TEMPLATE_DECL
2351 && (TREE_CODE (DECL_TEMPLATE_RESULT (olddecl))
2352 == FUNCTION_DECL))))
2353 {
2354 tree fn = olddecl;
2355
2356 if (TREE_CODE (fn) == TEMPLATE_DECL)
2357 fn = DECL_TEMPLATE_RESULT (olddecl);
2358
2359 new_redefines_gnu_inline = GNU_INLINE_P (fn) && DECL_INITIAL (fn);
2360 }
2361
2362 if (!new_redefines_gnu_inline)
2363 {
2364 DECL_INTERFACE_KNOWN (newdecl) |= DECL_INTERFACE_KNOWN (olddecl);
2365 DECL_NOT_REALLY_EXTERN (newdecl) |= DECL_NOT_REALLY_EXTERN (olddecl);
2366 DECL_COMDAT (newdecl) |= DECL_COMDAT (olddecl);
2367 }
2368 DECL_TEMPLATE_INSTANTIATED (newdecl)
2369 |= DECL_TEMPLATE_INSTANTIATED (olddecl);
2370 DECL_ODR_USED (newdecl) |= DECL_ODR_USED (olddecl);
2371
2372 /* If the OLDDECL is an instantiation and/or specialization,
2373 then the NEWDECL must be too. But, it may not yet be marked
2374 as such if the caller has created NEWDECL, but has not yet
2375 figured out that it is a redeclaration. */
2376 if (!DECL_USE_TEMPLATE (newdecl))
2377 DECL_USE_TEMPLATE (newdecl) = DECL_USE_TEMPLATE (olddecl);
2378
2379 /* Don't really know how much of the language-specific
2380 values we should copy from old to new. */
2381 DECL_IN_AGGR_P (newdecl) = DECL_IN_AGGR_P (olddecl);
2382 DECL_REPO_AVAILABLE_P (newdecl) = DECL_REPO_AVAILABLE_P (olddecl);
2383 DECL_INITIALIZED_IN_CLASS_P (newdecl)
2384 |= DECL_INITIALIZED_IN_CLASS_P (olddecl);
2385
2386 if (LANG_DECL_HAS_MIN (newdecl))
2387 {
2388 DECL_LANG_SPECIFIC (newdecl)->u.min.u2 =
2389 DECL_LANG_SPECIFIC (olddecl)->u.min.u2;
2390 if (DECL_TEMPLATE_INFO (newdecl))
2391 {
2392 new_template_info = DECL_TEMPLATE_INFO (newdecl);
2393 if (DECL_TEMPLATE_INSTANTIATION (olddecl)
2394 && DECL_TEMPLATE_SPECIALIZATION (newdecl))
2395 /* Remember the presence of explicit specialization args. */
2396 TINFO_USED_TEMPLATE_ID (DECL_TEMPLATE_INFO (olddecl))
2397 = TINFO_USED_TEMPLATE_ID (new_template_info);
2398 }
2399 DECL_TEMPLATE_INFO (newdecl) = DECL_TEMPLATE_INFO (olddecl);
2400 }
2401 /* Only functions have these fields. */
2402 if (DECL_DECLARES_FUNCTION_P (newdecl))
2403 {
2404 DECL_NONCONVERTING_P (newdecl) = DECL_NONCONVERTING_P (olddecl);
2405 DECL_BEFRIENDING_CLASSES (newdecl)
2406 = chainon (DECL_BEFRIENDING_CLASSES (newdecl),
2407 DECL_BEFRIENDING_CLASSES (olddecl));
2408 /* DECL_THUNKS is only valid for virtual functions,
2409 otherwise it is a DECL_FRIEND_CONTEXT. */
2410 if (DECL_VIRTUAL_P (newdecl))
2411 SET_DECL_THUNKS (newdecl, DECL_THUNKS (olddecl));
2412 }
2413 /* Only variables have this field. */
2414 else if (VAR_P (newdecl)
2415 && VAR_HAD_UNKNOWN_BOUND (olddecl))
2416 SET_VAR_HAD_UNKNOWN_BOUND (newdecl);
2417 }
2418
2419 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2420 {
2421 tree parm;
2422
2423 /* Merge parameter attributes. */
2424 tree oldarg, newarg;
2425 for (oldarg = DECL_ARGUMENTS(olddecl),
2426 newarg = DECL_ARGUMENTS(newdecl);
2427 oldarg && newarg;
2428 oldarg = DECL_CHAIN(oldarg), newarg = DECL_CHAIN(newarg)) {
2429 DECL_ATTRIBUTES (newarg)
2430 = (*targetm.merge_decl_attributes) (oldarg, newarg);
2431 DECL_ATTRIBUTES (oldarg) = DECL_ATTRIBUTES (newarg);
2432 }
2433
2434 if (DECL_TEMPLATE_INSTANTIATION (olddecl)
2435 && !DECL_TEMPLATE_INSTANTIATION (newdecl))
2436 {
2437 /* If newdecl is not a specialization, then it is not a
2438 template-related function at all. And that means that we
2439 should have exited above, returning 0. */
2440 gcc_assert (DECL_TEMPLATE_SPECIALIZATION (newdecl));
2441
2442 if (DECL_ODR_USED (olddecl))
2443 /* From [temp.expl.spec]:
2444
2445 If a template, a member template or the member of a class
2446 template is explicitly specialized then that
2447 specialization shall be declared before the first use of
2448 that specialization that would cause an implicit
2449 instantiation to take place, in every translation unit in
2450 which such a use occurs. */
2451 error ("explicit specialization of %qD after first use",
2452 olddecl);
2453
2454 SET_DECL_TEMPLATE_SPECIALIZATION (olddecl);
2455 DECL_COMDAT (newdecl) = (TREE_PUBLIC (newdecl)
2456 && DECL_DECLARED_INLINE_P (newdecl));
2457
2458 /* Don't propagate visibility from the template to the
2459 specialization here. We'll do that in determine_visibility if
2460 appropriate. */
2461 DECL_VISIBILITY_SPECIFIED (olddecl) = 0;
2462
2463 /* [temp.expl.spec/14] We don't inline explicit specialization
2464 just because the primary template says so. */
2465 gcc_assert (!merge_attr);
2466
2467 DECL_DECLARED_INLINE_P (olddecl)
2468 = DECL_DECLARED_INLINE_P (newdecl);
2469
2470 DECL_DISREGARD_INLINE_LIMITS (olddecl)
2471 = DECL_DISREGARD_INLINE_LIMITS (newdecl);
2472
2473 DECL_UNINLINABLE (olddecl) = DECL_UNINLINABLE (newdecl);
2474 }
2475 else if (new_defines_function && DECL_INITIAL (olddecl))
2476 {
2477 /* Never inline re-defined extern inline functions.
2478 FIXME: this could be better handled by keeping both
2479 function as separate declarations. */
2480 DECL_UNINLINABLE (newdecl) = 1;
2481 }
2482 else
2483 {
2484 if (DECL_PENDING_INLINE_P (olddecl))
2485 {
2486 DECL_PENDING_INLINE_P (newdecl) = 1;
2487 DECL_PENDING_INLINE_INFO (newdecl)
2488 = DECL_PENDING_INLINE_INFO (olddecl);
2489 }
2490 else if (DECL_PENDING_INLINE_P (newdecl))
2491 ;
2492 else if (DECL_SAVED_FUNCTION_DATA (newdecl) == NULL)
2493 DECL_SAVED_FUNCTION_DATA (newdecl)
2494 = DECL_SAVED_FUNCTION_DATA (olddecl);
2495
2496 DECL_DECLARED_INLINE_P (newdecl) |= DECL_DECLARED_INLINE_P (olddecl);
2497
2498 DECL_UNINLINABLE (newdecl) = DECL_UNINLINABLE (olddecl)
2499 = (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl));
2500
2501 DECL_DISREGARD_INLINE_LIMITS (newdecl)
2502 = DECL_DISREGARD_INLINE_LIMITS (olddecl)
2503 = (DECL_DISREGARD_INLINE_LIMITS (newdecl)
2504 || DECL_DISREGARD_INLINE_LIMITS (olddecl));
2505 }
2506
2507 /* Preserve abstractness on cloned [cd]tors. */
2508 DECL_ABSTRACT_P (newdecl) = DECL_ABSTRACT_P (olddecl);
2509
2510 /* Update newdecl's parms to point at olddecl. */
2511 for (parm = DECL_ARGUMENTS (newdecl); parm;
2512 parm = DECL_CHAIN (parm))
2513 DECL_CONTEXT (parm) = olddecl;
2514
2515 if (! types_match)
2516 {
2517 SET_DECL_LANGUAGE (olddecl, DECL_LANGUAGE (newdecl));
2518 COPY_DECL_ASSEMBLER_NAME (newdecl, olddecl);
2519 COPY_DECL_RTL (newdecl, olddecl);
2520 }
2521 if (! types_match || new_defines_function)
2522 {
2523 /* These need to be copied so that the names are available.
2524 Note that if the types do match, we'll preserve inline
2525 info and other bits, but if not, we won't. */
2526 DECL_ARGUMENTS (olddecl) = DECL_ARGUMENTS (newdecl);
2527 DECL_RESULT (olddecl) = DECL_RESULT (newdecl);
2528 }
2529 /* If redeclaring a builtin function, it stays built in
2530 if newdecl is a gnu_inline definition, or if newdecl is just
2531 a declaration. */
2532 if (DECL_BUILT_IN (olddecl)
2533 && (new_defines_function ? GNU_INLINE_P (newdecl) : types_match))
2534 {
2535 DECL_BUILT_IN_CLASS (newdecl) = DECL_BUILT_IN_CLASS (olddecl);
2536 DECL_FUNCTION_CODE (newdecl) = DECL_FUNCTION_CODE (olddecl);
2537 /* If we're keeping the built-in definition, keep the rtl,
2538 regardless of declaration matches. */
2539 COPY_DECL_RTL (olddecl, newdecl);
2540 if (DECL_BUILT_IN_CLASS (newdecl) == BUILT_IN_NORMAL)
2541 {
2542 enum built_in_function fncode = DECL_FUNCTION_CODE (newdecl);
2543 switch (fncode)
2544 {
2545 /* If a compatible prototype of these builtin functions
2546 is seen, assume the runtime implements it with the
2547 expected semantics. */
2548 case BUILT_IN_STPCPY:
2549 if (builtin_decl_explicit_p (fncode))
2550 set_builtin_decl_implicit_p (fncode, true);
2551 break;
2552 default:
2553 if (builtin_decl_explicit_p (fncode))
2554 set_builtin_decl_declared_p (fncode, true);
2555 break;
2556 }
2557 }
2558
2559 copy_attributes_to_builtin (newdecl);
2560 }
2561 if (new_defines_function)
2562 /* If defining a function declared with other language
2563 linkage, use the previously declared language linkage. */
2564 SET_DECL_LANGUAGE (newdecl, DECL_LANGUAGE (olddecl));
2565 else if (types_match)
2566 {
2567 DECL_RESULT (newdecl) = DECL_RESULT (olddecl);
2568 /* Don't clear out the arguments if we're just redeclaring a
2569 function. */
2570 if (DECL_ARGUMENTS (olddecl))
2571 DECL_ARGUMENTS (newdecl) = DECL_ARGUMENTS (olddecl);
2572 }
2573 }
2574 else if (TREE_CODE (newdecl) == NAMESPACE_DECL)
2575 NAMESPACE_LEVEL (newdecl) = NAMESPACE_LEVEL (olddecl);
2576
2577 /* Now preserve various other info from the definition. */
2578 TREE_ADDRESSABLE (newdecl) = TREE_ADDRESSABLE (olddecl);
2579 TREE_ASM_WRITTEN (newdecl) = TREE_ASM_WRITTEN (olddecl);
2580 DECL_COMMON (newdecl) = DECL_COMMON (olddecl);
2581 COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
2582
2583 /* Warn about conflicting visibility specifications. */
2584 if (DECL_VISIBILITY_SPECIFIED (olddecl)
2585 && DECL_VISIBILITY_SPECIFIED (newdecl)
2586 && DECL_VISIBILITY (newdecl) != DECL_VISIBILITY (olddecl))
2587 {
2588 if (warning_at (DECL_SOURCE_LOCATION (newdecl), OPT_Wattributes,
2589 "%qD: visibility attribute ignored because it "
2590 "conflicts with previous declaration", newdecl))
2591 inform (DECL_SOURCE_LOCATION (olddecl),
2592 "previous declaration of %qD", olddecl);
2593 }
2594 /* Choose the declaration which specified visibility. */
2595 if (DECL_VISIBILITY_SPECIFIED (olddecl))
2596 {
2597 DECL_VISIBILITY (newdecl) = DECL_VISIBILITY (olddecl);
2598 DECL_VISIBILITY_SPECIFIED (newdecl) = 1;
2599 }
2600 /* Init priority used to be merged from newdecl to olddecl by the memcpy,
2601 so keep this behavior. */
2602 if (VAR_P (newdecl) && DECL_HAS_INIT_PRIORITY_P (newdecl))
2603 {
2604 SET_DECL_INIT_PRIORITY (olddecl, DECL_INIT_PRIORITY (newdecl));
2605 DECL_HAS_INIT_PRIORITY_P (olddecl) = 1;
2606 }
2607 /* Likewise for DECL_ALIGN, DECL_USER_ALIGN and DECL_PACKED. */
2608 if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
2609 {
2610 SET_DECL_ALIGN (newdecl, DECL_ALIGN (olddecl));
2611 DECL_USER_ALIGN (newdecl) |= DECL_USER_ALIGN (olddecl);
2612 }
2613 DECL_USER_ALIGN (olddecl) = DECL_USER_ALIGN (newdecl);
2614 if (DECL_WARN_IF_NOT_ALIGN (olddecl)
2615 > DECL_WARN_IF_NOT_ALIGN (newdecl))
2616 SET_DECL_WARN_IF_NOT_ALIGN (newdecl,
2617 DECL_WARN_IF_NOT_ALIGN (olddecl));
2618 if (TREE_CODE (newdecl) == FIELD_DECL)
2619 DECL_PACKED (olddecl) = DECL_PACKED (newdecl);
2620
2621 /* The DECL_LANG_SPECIFIC information in OLDDECL will be replaced
2622 with that from NEWDECL below. */
2623 if (DECL_LANG_SPECIFIC (olddecl))
2624 {
2625 gcc_assert (DECL_LANG_SPECIFIC (olddecl)
2626 != DECL_LANG_SPECIFIC (newdecl));
2627 ggc_free (DECL_LANG_SPECIFIC (olddecl));
2628 }
2629
2630 /* Merge the USED information. */
2631 if (TREE_USED (olddecl))
2632 TREE_USED (newdecl) = 1;
2633 else if (TREE_USED (newdecl))
2634 TREE_USED (olddecl) = 1;
2635 if (VAR_P (newdecl))
2636 {
2637 if (DECL_READ_P (olddecl))
2638 DECL_READ_P (newdecl) = 1;
2639 else if (DECL_READ_P (newdecl))
2640 DECL_READ_P (olddecl) = 1;
2641 }
2642 if (DECL_PRESERVE_P (olddecl))
2643 DECL_PRESERVE_P (newdecl) = 1;
2644 else if (DECL_PRESERVE_P (newdecl))
2645 DECL_PRESERVE_P (olddecl) = 1;
2646
2647 /* Merge the DECL_FUNCTION_VERSIONED information. newdecl will be copied
2648 to olddecl and deleted. */
2649 if (TREE_CODE (newdecl) == FUNCTION_DECL
2650 && DECL_FUNCTION_VERSIONED (olddecl))
2651 {
2652 /* Set the flag for newdecl so that it gets copied to olddecl. */
2653 DECL_FUNCTION_VERSIONED (newdecl) = 1;
2654 /* newdecl will be purged after copying to olddecl and is no longer
2655 a version. */
2656 cgraph_node::delete_function_version_by_decl (newdecl);
2657 }
2658
2659 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2660 {
2661 int function_size;
2662 struct symtab_node *snode = symtab_node::get (olddecl);
2663
2664 function_size = sizeof (struct tree_decl_common);
2665
2666 memcpy ((char *) olddecl + sizeof (struct tree_common),
2667 (char *) newdecl + sizeof (struct tree_common),
2668 function_size - sizeof (struct tree_common));
2669
2670 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
2671 (char *) newdecl + sizeof (struct tree_decl_common),
2672 sizeof (struct tree_function_decl) - sizeof (struct tree_decl_common));
2673
2674 /* Preserve symtab node mapping. */
2675 olddecl->decl_with_vis.symtab_node = snode;
2676
2677 if (new_template_info)
2678 /* If newdecl is a template instantiation, it is possible that
2679 the following sequence of events has occurred:
2680
2681 o A friend function was declared in a class template. The
2682 class template was instantiated.
2683
2684 o The instantiation of the friend declaration was
2685 recorded on the instantiation list, and is newdecl.
2686
2687 o Later, however, instantiate_class_template called pushdecl
2688 on the newdecl to perform name injection. But, pushdecl in
2689 turn called duplicate_decls when it discovered that another
2690 declaration of a global function with the same name already
2691 existed.
2692
2693 o Here, in duplicate_decls, we decided to clobber newdecl.
2694
2695 If we're going to do that, we'd better make sure that
2696 olddecl, and not newdecl, is on the list of
2697 instantiations so that if we try to do the instantiation
2698 again we won't get the clobbered declaration. */
2699 reregister_specialization (newdecl,
2700 new_template_info,
2701 olddecl);
2702 }
2703 else
2704 {
2705 size_t size = tree_code_size (TREE_CODE (newdecl));
2706
2707 memcpy ((char *) olddecl + sizeof (struct tree_common),
2708 (char *) newdecl + sizeof (struct tree_common),
2709 sizeof (struct tree_decl_common) - sizeof (struct tree_common));
2710 switch (TREE_CODE (newdecl))
2711 {
2712 case LABEL_DECL:
2713 case VAR_DECL:
2714 case RESULT_DECL:
2715 case PARM_DECL:
2716 case FIELD_DECL:
2717 case TYPE_DECL:
2718 case CONST_DECL:
2719 {
2720 struct symtab_node *snode = NULL;
2721
2722 if (VAR_P (newdecl)
2723 && (TREE_STATIC (olddecl) || TREE_PUBLIC (olddecl)
2724 || DECL_EXTERNAL (olddecl)))
2725 snode = symtab_node::get (olddecl);
2726 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
2727 (char *) newdecl + sizeof (struct tree_decl_common),
2728 size - sizeof (struct tree_decl_common)
2729 + TREE_CODE_LENGTH (TREE_CODE (newdecl)) * sizeof (char *));
2730 if (VAR_P (newdecl))
2731 olddecl->decl_with_vis.symtab_node = snode;
2732 }
2733 break;
2734 default:
2735 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
2736 (char *) newdecl + sizeof (struct tree_decl_common),
2737 sizeof (struct tree_decl_non_common) - sizeof (struct tree_decl_common)
2738 + TREE_CODE_LENGTH (TREE_CODE (newdecl)) * sizeof (char *));
2739 break;
2740 }
2741 }
2742
2743 if (VAR_OR_FUNCTION_DECL_P (newdecl))
2744 {
2745 if (DECL_EXTERNAL (olddecl)
2746 || TREE_PUBLIC (olddecl)
2747 || TREE_STATIC (olddecl))
2748 {
2749 /* Merge the section attribute.
2750 We want to issue an error if the sections conflict but that must be
2751 done later in decl_attributes since we are called before attributes
2752 are assigned. */
2753 if (DECL_SECTION_NAME (newdecl) != NULL)
2754 set_decl_section_name (olddecl, DECL_SECTION_NAME (newdecl));
2755
2756 if (DECL_ONE_ONLY (newdecl))
2757 {
2758 struct symtab_node *oldsym, *newsym;
2759 if (TREE_CODE (olddecl) == FUNCTION_DECL)
2760 oldsym = cgraph_node::get_create (olddecl);
2761 else
2762 oldsym = varpool_node::get_create (olddecl);
2763 newsym = symtab_node::get (newdecl);
2764 oldsym->set_comdat_group (newsym->get_comdat_group ());
2765 }
2766 }
2767
2768 if (VAR_P (newdecl)
2769 && CP_DECL_THREAD_LOCAL_P (newdecl))
2770 {
2771 CP_DECL_THREAD_LOCAL_P (olddecl) = true;
2772 if (!processing_template_decl)
2773 set_decl_tls_model (olddecl, DECL_TLS_MODEL (newdecl));
2774 }
2775 }
2776
2777 DECL_UID (olddecl) = olddecl_uid;
2778 if (olddecl_friend)
2779 DECL_FRIEND_P (olddecl) = 1;
2780 if (hidden_friend)
2781 {
2782 DECL_ANTICIPATED (olddecl) = 1;
2783 DECL_HIDDEN_FRIEND_P (olddecl) = 1;
2784 }
2785
2786 /* NEWDECL contains the merged attribute lists.
2787 Update OLDDECL to be the same. */
2788 DECL_ATTRIBUTES (olddecl) = DECL_ATTRIBUTES (newdecl);
2789
2790 /* If OLDDECL had its DECL_RTL instantiated, re-invoke make_decl_rtl
2791 so that encode_section_info has a chance to look at the new decl
2792 flags and attributes. */
2793 if (DECL_RTL_SET_P (olddecl)
2794 && (TREE_CODE (olddecl) == FUNCTION_DECL
2795 || (VAR_P (olddecl)
2796 && TREE_STATIC (olddecl))))
2797 make_decl_rtl (olddecl);
2798
2799 /* The NEWDECL will no longer be needed. Because every out-of-class
2800 declaration of a member results in a call to duplicate_decls,
2801 freeing these nodes represents in a significant savings.
2802
2803 Before releasing the node, be sore to remove function from symbol
2804 table that might have been inserted there to record comdat group.
2805 Be sure to however do not free DECL_STRUCT_FUNCTION because this
2806 structure is shared in between newdecl and oldecl. */
2807 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2808 DECL_STRUCT_FUNCTION (newdecl) = NULL;
2809 if (VAR_OR_FUNCTION_DECL_P (newdecl))
2810 {
2811 struct symtab_node *snode = symtab_node::get (newdecl);
2812 if (snode)
2813 snode->remove ();
2814 }
2815
2816 /* Remove the associated constraints for newdecl, if any, before
2817 reclaiming memory. */
2818 if (flag_concepts)
2819 remove_constraints (newdecl);
2820
2821 ggc_free (newdecl);
2822
2823 return olddecl;
2824 }
2825
2826 /* Return zero if the declaration NEWDECL is valid
2827 when the declaration OLDDECL (assumed to be for the same name)
2828 has already been seen.
2829 Otherwise return an error message format string with a %s
2830 where the identifier should go. */
2831
2832 static const char *
redeclaration_error_message(tree newdecl,tree olddecl)2833 redeclaration_error_message (tree newdecl, tree olddecl)
2834 {
2835 if (TREE_CODE (newdecl) == TYPE_DECL)
2836 {
2837 /* Because C++ can put things into name space for free,
2838 constructs like "typedef struct foo { ... } foo"
2839 would look like an erroneous redeclaration. */
2840 if (same_type_p (TREE_TYPE (newdecl), TREE_TYPE (olddecl)))
2841 return NULL;
2842 else
2843 return G_("redefinition of %q#D");
2844 }
2845 else if (TREE_CODE (newdecl) == FUNCTION_DECL)
2846 {
2847 /* If this is a pure function, its olddecl will actually be
2848 the original initialization to `0' (which we force to call
2849 abort()). Don't complain about redefinition in this case. */
2850 if (DECL_LANG_SPECIFIC (olddecl) && DECL_PURE_VIRTUAL_P (olddecl)
2851 && DECL_INITIAL (olddecl) == NULL_TREE)
2852 return NULL;
2853
2854 /* If both functions come from different namespaces, this is not
2855 a redeclaration - this is a conflict with a used function. */
2856 if (DECL_NAMESPACE_SCOPE_P (olddecl)
2857 && DECL_CONTEXT (olddecl) != DECL_CONTEXT (newdecl)
2858 && ! decls_match (olddecl, newdecl))
2859 return G_("%qD conflicts with used function");
2860
2861 /* We'll complain about linkage mismatches in
2862 warn_extern_redeclared_static. */
2863
2864 /* Defining the same name twice is no good. */
2865 if (decl_defined_p (olddecl)
2866 && decl_defined_p (newdecl))
2867 {
2868 if (DECL_NAME (olddecl) == NULL_TREE)
2869 return G_("%q#D not declared in class");
2870 else if (!GNU_INLINE_P (olddecl)
2871 || GNU_INLINE_P (newdecl))
2872 return G_("redefinition of %q#D");
2873 }
2874
2875 if (DECL_DECLARED_INLINE_P (olddecl) && DECL_DECLARED_INLINE_P (newdecl))
2876 {
2877 bool olda = GNU_INLINE_P (olddecl);
2878 bool newa = GNU_INLINE_P (newdecl);
2879
2880 if (olda != newa)
2881 {
2882 if (newa)
2883 return G_("%q+D redeclared inline with "
2884 "%<gnu_inline%> attribute");
2885 else
2886 return G_("%q+D redeclared inline without "
2887 "%<gnu_inline%> attribute");
2888 }
2889 }
2890
2891 check_abi_tag_redeclaration
2892 (olddecl, lookup_attribute ("abi_tag", DECL_ATTRIBUTES (olddecl)),
2893 lookup_attribute ("abi_tag", DECL_ATTRIBUTES (newdecl)));
2894
2895 return NULL;
2896 }
2897 else if (TREE_CODE (newdecl) == TEMPLATE_DECL)
2898 {
2899 tree nt, ot;
2900
2901 if (TREE_CODE (DECL_TEMPLATE_RESULT (newdecl)) == TYPE_DECL)
2902 {
2903 if (COMPLETE_TYPE_P (TREE_TYPE (newdecl))
2904 && COMPLETE_TYPE_P (TREE_TYPE (olddecl)))
2905 return G_("redefinition of %q#D");
2906 return NULL;
2907 }
2908
2909 if (TREE_CODE (DECL_TEMPLATE_RESULT (newdecl)) != FUNCTION_DECL
2910 || (DECL_TEMPLATE_RESULT (newdecl)
2911 == DECL_TEMPLATE_RESULT (olddecl)))
2912 return NULL;
2913
2914 nt = DECL_TEMPLATE_RESULT (newdecl);
2915 if (DECL_TEMPLATE_INFO (nt))
2916 nt = DECL_TEMPLATE_RESULT (template_for_substitution (nt));
2917 ot = DECL_TEMPLATE_RESULT (olddecl);
2918 if (DECL_TEMPLATE_INFO (ot))
2919 ot = DECL_TEMPLATE_RESULT (template_for_substitution (ot));
2920 if (DECL_INITIAL (nt) && DECL_INITIAL (ot)
2921 && (!GNU_INLINE_P (ot) || GNU_INLINE_P (nt)))
2922 return G_("redefinition of %q#D");
2923
2924 if (DECL_DECLARED_INLINE_P (ot) && DECL_DECLARED_INLINE_P (nt))
2925 {
2926 bool olda = GNU_INLINE_P (ot);
2927 bool newa = GNU_INLINE_P (nt);
2928
2929 if (olda != newa)
2930 {
2931 if (newa)
2932 return G_("%q+D redeclared inline with "
2933 "%<gnu_inline%> attribute");
2934 else
2935 return G_("%q+D redeclared inline without "
2936 "%<gnu_inline%> attribute");
2937 }
2938 }
2939
2940 /* Core issue #226 (C++0x):
2941
2942 If a friend function template declaration specifies a
2943 default template-argument, that declaration shall be a
2944 definition and shall be the only declaration of the
2945 function template in the translation unit. */
2946 if ((cxx_dialect != cxx98)
2947 && TREE_CODE (ot) == FUNCTION_DECL && DECL_FRIEND_P (ot)
2948 && !check_default_tmpl_args (nt, DECL_TEMPLATE_PARMS (newdecl),
2949 /*is_primary=*/true,
2950 /*is_partial=*/false,
2951 /*is_friend_decl=*/2))
2952 return G_("redeclaration of friend %q#D "
2953 "may not have default template arguments");
2954
2955 return NULL;
2956 }
2957 else if (VAR_P (newdecl)
2958 && CP_DECL_THREAD_LOCAL_P (newdecl) != CP_DECL_THREAD_LOCAL_P (olddecl)
2959 && (! DECL_LANG_SPECIFIC (olddecl)
2960 || ! CP_DECL_THREADPRIVATE_P (olddecl)
2961 || CP_DECL_THREAD_LOCAL_P (newdecl)))
2962 {
2963 /* Only variables can be thread-local, and all declarations must
2964 agree on this property. */
2965 if (CP_DECL_THREAD_LOCAL_P (newdecl))
2966 return G_("thread-local declaration of %q#D follows "
2967 "non-thread-local declaration");
2968 else
2969 return G_("non-thread-local declaration of %q#D follows "
2970 "thread-local declaration");
2971 }
2972 else if (toplevel_bindings_p () || DECL_NAMESPACE_SCOPE_P (newdecl))
2973 {
2974 /* The objects have been declared at namespace scope. If either
2975 is a member of an anonymous union, then this is an invalid
2976 redeclaration. For example:
2977
2978 int i;
2979 union { int i; };
2980
2981 is invalid. */
2982 if ((VAR_P (newdecl) && DECL_ANON_UNION_VAR_P (newdecl))
2983 || (VAR_P (olddecl) && DECL_ANON_UNION_VAR_P (olddecl)))
2984 return G_("redeclaration of %q#D");
2985 /* If at least one declaration is a reference, there is no
2986 conflict. For example:
2987
2988 int i = 3;
2989 extern int i;
2990
2991 is valid. */
2992 if (DECL_EXTERNAL (newdecl) || DECL_EXTERNAL (olddecl))
2993 return NULL;
2994
2995 /* Static data member declared outside a class definition
2996 if the variable is defined within the class with constexpr
2997 specifier is declaration rather than definition (and
2998 deprecated). */
2999 if (cxx_dialect >= cxx17
3000 && VAR_P (olddecl)
3001 && DECL_CLASS_SCOPE_P (olddecl)
3002 && DECL_DECLARED_CONSTEXPR_P (olddecl)
3003 && !DECL_INITIAL (newdecl))
3004 {
3005 DECL_EXTERNAL (newdecl) = 1;
3006 /* For now, only warn with explicit -Wdeprecated. */
3007 if (global_options_set.x_warn_deprecated
3008 && warning_at (DECL_SOURCE_LOCATION (newdecl), OPT_Wdeprecated,
3009 "redundant redeclaration of %<constexpr%> static "
3010 "data member %qD", newdecl))
3011 inform (DECL_SOURCE_LOCATION (olddecl),
3012 "previous declaration of %qD", olddecl);
3013 return NULL;
3014 }
3015
3016 /* Reject two definitions. */
3017 return G_("redefinition of %q#D");
3018 }
3019 else
3020 {
3021 /* Objects declared with block scope: */
3022 /* Reject two definitions, and reject a definition
3023 together with an external reference. */
3024 if (!(DECL_EXTERNAL (newdecl) && DECL_EXTERNAL (olddecl)))
3025 return G_("redeclaration of %q#D");
3026 return NULL;
3027 }
3028 }
3029
3030
3031 /* Hash and equality functions for the named_label table. */
3032
3033 hashval_t
hash(const value_type entry)3034 named_label_hash::hash (const value_type entry)
3035 {
3036 return IDENTIFIER_HASH_VALUE (entry->name);
3037 }
3038
3039 bool
equal(const value_type entry,compare_type name)3040 named_label_hash::equal (const value_type entry, compare_type name)
3041 {
3042 return name == entry->name;
3043 }
3044
3045 /* Look for a label named ID in the current function. If one cannot
3046 be found, create one. Return the named_label_entry, or NULL on
3047 failure. */
3048
3049 static named_label_entry *
lookup_label_1(tree id,bool making_local_p)3050 lookup_label_1 (tree id, bool making_local_p)
3051 {
3052 /* You can't use labels at global scope. */
3053 if (current_function_decl == NULL_TREE)
3054 {
3055 error ("label %qE referenced outside of any function", id);
3056 return NULL;
3057 }
3058
3059 if (!named_labels)
3060 named_labels = hash_table<named_label_hash>::create_ggc (13);
3061
3062 hashval_t hash = IDENTIFIER_HASH_VALUE (id);
3063 named_label_entry **slot
3064 = named_labels->find_slot_with_hash (id, hash, INSERT);
3065 named_label_entry *old = *slot;
3066
3067 if (old && old->label_decl)
3068 {
3069 if (!making_local_p)
3070 return old;
3071
3072 if (old->binding_level == current_binding_level)
3073 {
3074 error ("local label %qE conflicts with existing label", id);
3075 inform (DECL_SOURCE_LOCATION (old->label_decl), "previous label");
3076 return NULL;
3077 }
3078 }
3079
3080 /* We are making a new decl, create or reuse the named_label_entry */
3081 named_label_entry *ent = NULL;
3082 if (old && !old->label_decl)
3083 ent = old;
3084 else
3085 {
3086 ent = ggc_cleared_alloc<named_label_entry> ();
3087 ent->name = id;
3088 ent->outer = old;
3089 *slot = ent;
3090 }
3091
3092 /* Now create the LABEL_DECL. */
3093 tree decl = build_decl (input_location, LABEL_DECL, id, void_type_node);
3094
3095 DECL_CONTEXT (decl) = current_function_decl;
3096 SET_DECL_MODE (decl, VOIDmode);
3097 if (making_local_p)
3098 {
3099 C_DECLARED_LABEL_FLAG (decl) = true;
3100 DECL_CHAIN (decl) = current_binding_level->names;
3101 current_binding_level->names = decl;
3102 }
3103
3104 ent->label_decl = decl;
3105
3106 return ent;
3107 }
3108
3109 /* Wrapper for lookup_label_1. */
3110
3111 tree
lookup_label(tree id)3112 lookup_label (tree id)
3113 {
3114 bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
3115 named_label_entry *ent = lookup_label_1 (id, false);
3116 timevar_cond_stop (TV_NAME_LOOKUP, subtime);
3117 return ent ? ent->label_decl : NULL_TREE;
3118 }
3119
3120 tree
declare_local_label(tree id)3121 declare_local_label (tree id)
3122 {
3123 bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
3124 named_label_entry *ent = lookup_label_1 (id, true);
3125 timevar_cond_stop (TV_NAME_LOOKUP, subtime);
3126 return ent ? ent->label_decl : NULL_TREE;
3127 }
3128
3129 /* Returns nonzero if it is ill-formed to jump past the declaration of
3130 DECL. Returns 2 if it's also a real problem. */
3131
3132 static int
decl_jump_unsafe(tree decl)3133 decl_jump_unsafe (tree decl)
3134 {
3135 /* [stmt.dcl]/3: A program that jumps from a point where a local variable
3136 with automatic storage duration is not in scope to a point where it is
3137 in scope is ill-formed unless the variable has scalar type, class type
3138 with a trivial default constructor and a trivial destructor, a
3139 cv-qualified version of one of these types, or an array of one of the
3140 preceding types and is declared without an initializer (8.5). */
3141 tree type = TREE_TYPE (decl);
3142
3143 if (!VAR_P (decl) || TREE_STATIC (decl)
3144 || type == error_mark_node)
3145 return 0;
3146
3147 if (DECL_NONTRIVIALLY_INITIALIZED_P (decl)
3148 || variably_modified_type_p (type, NULL_TREE))
3149 return 2;
3150
3151 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
3152 return 1;
3153
3154 return 0;
3155 }
3156
3157 /* A subroutine of check_previous_goto_1 and check_goto to identify a branch
3158 to the user. */
3159
3160 static bool
identify_goto(tree decl,location_t loc,const location_t * locus,diagnostic_t diag_kind)3161 identify_goto (tree decl, location_t loc, const location_t *locus,
3162 diagnostic_t diag_kind)
3163 {
3164 bool complained
3165 = emit_diagnostic (diag_kind, loc, 0,
3166 decl ? N_("jump to label %qD")
3167 : N_("jump to case label"), decl);
3168 if (complained && locus)
3169 inform (*locus, " from here");
3170 return complained;
3171 }
3172
3173 /* Check that a single previously seen jump to a newly defined label
3174 is OK. DECL is the LABEL_DECL or 0; LEVEL is the binding_level for
3175 the jump context; NAMES are the names in scope in LEVEL at the jump
3176 context; LOCUS is the source position of the jump or 0. Returns
3177 true if all is well. */
3178
3179 static bool
check_previous_goto_1(tree decl,cp_binding_level * level,tree names,bool exited_omp,const location_t * locus)3180 check_previous_goto_1 (tree decl, cp_binding_level* level, tree names,
3181 bool exited_omp, const location_t *locus)
3182 {
3183 cp_binding_level *b;
3184 bool complained = false;
3185 int identified = 0;
3186 bool saw_eh = false, saw_omp = false, saw_tm = false, saw_cxif = false;
3187
3188 if (exited_omp)
3189 {
3190 complained = identify_goto (decl, input_location, locus, DK_ERROR);
3191 if (complained)
3192 inform (input_location, " exits OpenMP structured block");
3193 saw_omp = true;
3194 identified = 2;
3195 }
3196
3197 for (b = current_binding_level; b ; b = b->level_chain)
3198 {
3199 tree new_decls, old_decls = (b == level ? names : NULL_TREE);
3200
3201 for (new_decls = b->names; new_decls != old_decls;
3202 new_decls = (DECL_P (new_decls) ? DECL_CHAIN (new_decls)
3203 : TREE_CHAIN (new_decls)))
3204 {
3205 int problem = decl_jump_unsafe (new_decls);
3206 if (! problem)
3207 continue;
3208
3209 if (!identified)
3210 {
3211 complained = identify_goto (decl, input_location, locus,
3212 DK_PERMERROR);
3213 identified = 1;
3214 }
3215 if (complained)
3216 {
3217 if (problem > 1)
3218 inform (DECL_SOURCE_LOCATION (new_decls),
3219 " crosses initialization of %q#D", new_decls);
3220 else
3221 inform (DECL_SOURCE_LOCATION (new_decls),
3222 " enters scope of %q#D, which has "
3223 "non-trivial destructor", new_decls);
3224 }
3225 }
3226
3227 if (b == level)
3228 break;
3229
3230 const char *inf = NULL;
3231 location_t loc = input_location;
3232 switch (b->kind)
3233 {
3234 case sk_try:
3235 if (!saw_eh)
3236 inf = N_("enters try block");
3237 saw_eh = true;
3238 break;
3239
3240 case sk_catch:
3241 if (!saw_eh)
3242 inf = N_("enters catch block");
3243 saw_eh = true;
3244 break;
3245
3246 case sk_omp:
3247 if (!saw_omp)
3248 inf = N_("enters OpenMP structured block");
3249 saw_omp = true;
3250 break;
3251
3252 case sk_transaction:
3253 if (!saw_tm)
3254 inf = N_("enters synchronized or atomic statement");
3255 saw_tm = true;
3256 break;
3257
3258 case sk_block:
3259 if (!saw_cxif && level_for_constexpr_if (b->level_chain))
3260 {
3261 inf = N_("enters constexpr if statement");
3262 loc = EXPR_LOCATION (b->level_chain->this_entity);
3263 saw_cxif = true;
3264 }
3265 break;
3266
3267 default:
3268 break;
3269 }
3270
3271 if (inf)
3272 {
3273 if (identified < 2)
3274 complained = identify_goto (decl, input_location, locus, DK_ERROR);
3275 identified = 2;
3276 if (complained)
3277 inform (loc, " %s", inf);
3278 }
3279 }
3280
3281 return !identified;
3282 }
3283
3284 static void
check_previous_goto(tree decl,struct named_label_use_entry * use)3285 check_previous_goto (tree decl, struct named_label_use_entry *use)
3286 {
3287 check_previous_goto_1 (decl, use->binding_level,
3288 use->names_in_scope, use->in_omp_scope,
3289 &use->o_goto_locus);
3290 }
3291
3292 static bool
check_switch_goto(cp_binding_level * level)3293 check_switch_goto (cp_binding_level* level)
3294 {
3295 return check_previous_goto_1 (NULL_TREE, level, level->names, false, NULL);
3296 }
3297
3298 /* Check that a new jump to a label DECL is OK. Called by
3299 finish_goto_stmt. */
3300
3301 void
check_goto(tree decl)3302 check_goto (tree decl)
3303 {
3304 /* We can't know where a computed goto is jumping.
3305 So we assume that it's OK. */
3306 if (TREE_CODE (decl) != LABEL_DECL)
3307 return;
3308
3309 /* We didn't record any information about this label when we created it,
3310 and there's not much point since it's trivial to analyze as a return. */
3311 if (decl == cdtor_label)
3312 return;
3313
3314 hashval_t hash = IDENTIFIER_HASH_VALUE (DECL_NAME (decl));
3315 named_label_entry **slot
3316 = named_labels->find_slot_with_hash (DECL_NAME (decl), hash, NO_INSERT);
3317 named_label_entry *ent = *slot;
3318
3319 /* If the label hasn't been defined yet, defer checking. */
3320 if (! DECL_INITIAL (decl))
3321 {
3322 /* Don't bother creating another use if the last goto had the
3323 same data, and will therefore create the same set of errors. */
3324 if (ent->uses
3325 && ent->uses->names_in_scope == current_binding_level->names)
3326 return;
3327
3328 named_label_use_entry *new_use
3329 = ggc_alloc<named_label_use_entry> ();
3330 new_use->binding_level = current_binding_level;
3331 new_use->names_in_scope = current_binding_level->names;
3332 new_use->o_goto_locus = input_location;
3333 new_use->in_omp_scope = false;
3334
3335 new_use->next = ent->uses;
3336 ent->uses = new_use;
3337 return;
3338 }
3339
3340 bool saw_catch = false, complained = false;
3341 int identified = 0;
3342 tree bad;
3343 unsigned ix;
3344
3345 if (ent->in_try_scope || ent->in_catch_scope || ent->in_transaction_scope
3346 || ent->in_constexpr_if
3347 || ent->in_omp_scope || !vec_safe_is_empty (ent->bad_decls))
3348 {
3349 diagnostic_t diag_kind = DK_PERMERROR;
3350 if (ent->in_try_scope || ent->in_catch_scope || ent->in_constexpr_if
3351 || ent->in_transaction_scope || ent->in_omp_scope)
3352 diag_kind = DK_ERROR;
3353 complained = identify_goto (decl, DECL_SOURCE_LOCATION (decl),
3354 &input_location, diag_kind);
3355 identified = 1 + (diag_kind == DK_ERROR);
3356 }
3357
3358 FOR_EACH_VEC_SAFE_ELT (ent->bad_decls, ix, bad)
3359 {
3360 int u = decl_jump_unsafe (bad);
3361
3362 if (u > 1 && DECL_ARTIFICIAL (bad))
3363 {
3364 /* Can't skip init of __exception_info. */
3365 if (identified == 1)
3366 {
3367 complained = identify_goto (decl, DECL_SOURCE_LOCATION (decl),
3368 &input_location, DK_ERROR);
3369 identified = 2;
3370 }
3371 if (complained)
3372 inform (DECL_SOURCE_LOCATION (bad), " enters catch block");
3373 saw_catch = true;
3374 }
3375 else if (complained)
3376 {
3377 if (u > 1)
3378 inform (DECL_SOURCE_LOCATION (bad),
3379 " skips initialization of %q#D", bad);
3380 else
3381 inform (DECL_SOURCE_LOCATION (bad),
3382 " enters scope of %q#D which has "
3383 "non-trivial destructor", bad);
3384 }
3385 }
3386
3387 if (complained)
3388 {
3389 if (ent->in_try_scope)
3390 inform (input_location, " enters try block");
3391 else if (ent->in_catch_scope && !saw_catch)
3392 inform (input_location, " enters catch block");
3393 else if (ent->in_transaction_scope)
3394 inform (input_location, " enters synchronized or atomic statement");
3395 else if (ent->in_constexpr_if)
3396 inform (input_location, " enters %<constexpr%> if statement");
3397 }
3398
3399 if (ent->in_omp_scope)
3400 {
3401 if (complained)
3402 inform (input_location, " enters OpenMP structured block");
3403 }
3404 else if (flag_openmp)
3405 for (cp_binding_level *b = current_binding_level; b ; b = b->level_chain)
3406 {
3407 if (b == ent->binding_level)
3408 break;
3409 if (b->kind == sk_omp)
3410 {
3411 if (identified < 2)
3412 {
3413 complained = identify_goto (decl,
3414 DECL_SOURCE_LOCATION (decl),
3415 &input_location, DK_ERROR);
3416 identified = 2;
3417 }
3418 if (complained)
3419 inform (input_location, " exits OpenMP structured block");
3420 break;
3421 }
3422 }
3423 }
3424
3425 /* Check that a return is ok wrt OpenMP structured blocks.
3426 Called by finish_return_stmt. Returns true if all is well. */
3427
3428 bool
check_omp_return(void)3429 check_omp_return (void)
3430 {
3431 for (cp_binding_level *b = current_binding_level; b ; b = b->level_chain)
3432 if (b->kind == sk_omp)
3433 {
3434 error ("invalid exit from OpenMP structured block");
3435 return false;
3436 }
3437 else if (b->kind == sk_function_parms)
3438 break;
3439 return true;
3440 }
3441
3442 /* Define a label, specifying the location in the source file.
3443 Return the LABEL_DECL node for the label. */
3444
3445 static tree
define_label_1(location_t location,tree name)3446 define_label_1 (location_t location, tree name)
3447 {
3448 /* After labels, make any new cleanups in the function go into their
3449 own new (temporary) binding contour. */
3450 for (cp_binding_level *p = current_binding_level;
3451 p->kind != sk_function_parms;
3452 p = p->level_chain)
3453 p->more_cleanups_ok = 0;
3454
3455 named_label_entry *ent = lookup_label_1 (name, false);
3456 tree decl = ent->label_decl;
3457
3458 if (DECL_INITIAL (decl) != NULL_TREE)
3459 {
3460 error ("duplicate label %qD", decl);
3461 return error_mark_node;
3462 }
3463 else
3464 {
3465 /* Mark label as having been defined. */
3466 DECL_INITIAL (decl) = error_mark_node;
3467 /* Say where in the source. */
3468 DECL_SOURCE_LOCATION (decl) = location;
3469
3470 ent->binding_level = current_binding_level;
3471 ent->names_in_scope = current_binding_level->names;
3472
3473 for (named_label_use_entry *use = ent->uses; use; use = use->next)
3474 check_previous_goto (decl, use);
3475 ent->uses = NULL;
3476 }
3477
3478 return decl;
3479 }
3480
3481 /* Wrapper for define_label_1. */
3482
3483 tree
define_label(location_t location,tree name)3484 define_label (location_t location, tree name)
3485 {
3486 bool running = timevar_cond_start (TV_NAME_LOOKUP);
3487 tree ret = define_label_1 (location, name);
3488 timevar_cond_stop (TV_NAME_LOOKUP, running);
3489 return ret;
3490 }
3491
3492
3493 struct cp_switch
3494 {
3495 cp_binding_level *level;
3496 struct cp_switch *next;
3497 /* The SWITCH_STMT being built. */
3498 tree switch_stmt;
3499 /* A splay-tree mapping the low element of a case range to the high
3500 element, or NULL_TREE if there is no high element. Used to
3501 determine whether or not a new case label duplicates an old case
3502 label. We need a tree, rather than simply a hash table, because
3503 of the GNU case range extension. */
3504 splay_tree cases;
3505 /* Remember whether there was a case value that is outside the
3506 range of the original type of the controlling expression. */
3507 bool outside_range_p;
3508 /* Remember whether a default: case label has been seen. */
3509 bool has_default_p;
3510 /* Remember whether a BREAK_STMT has been seen in this SWITCH_STMT. */
3511 bool break_stmt_seen_p;
3512 /* Set if inside of {FOR,DO,WHILE}_BODY nested inside of a switch,
3513 where BREAK_STMT doesn't belong to the SWITCH_STMT. */
3514 bool in_loop_body_p;
3515 };
3516
3517 /* A stack of the currently active switch statements. The innermost
3518 switch statement is on the top of the stack. There is no need to
3519 mark the stack for garbage collection because it is only active
3520 during the processing of the body of a function, and we never
3521 collect at that point. */
3522
3523 static struct cp_switch *switch_stack;
3524
3525 /* Called right after a switch-statement condition is parsed.
3526 SWITCH_STMT is the switch statement being parsed. */
3527
3528 void
push_switch(tree switch_stmt)3529 push_switch (tree switch_stmt)
3530 {
3531 struct cp_switch *p = XNEW (struct cp_switch);
3532 p->level = current_binding_level;
3533 p->next = switch_stack;
3534 p->switch_stmt = switch_stmt;
3535 p->cases = splay_tree_new (case_compare, NULL, NULL);
3536 p->outside_range_p = false;
3537 p->has_default_p = false;
3538 p->break_stmt_seen_p = false;
3539 p->in_loop_body_p = false;
3540 switch_stack = p;
3541 }
3542
3543 void
pop_switch(void)3544 pop_switch (void)
3545 {
3546 struct cp_switch *cs = switch_stack;
3547 location_t switch_location;
3548
3549 /* Emit warnings as needed. */
3550 switch_location = EXPR_LOC_OR_LOC (cs->switch_stmt, input_location);
3551 const bool bool_cond_p
3552 = (SWITCH_STMT_TYPE (cs->switch_stmt)
3553 && TREE_CODE (SWITCH_STMT_TYPE (cs->switch_stmt)) == BOOLEAN_TYPE);
3554 if (!processing_template_decl)
3555 c_do_switch_warnings (cs->cases, switch_location,
3556 SWITCH_STMT_TYPE (cs->switch_stmt),
3557 SWITCH_STMT_COND (cs->switch_stmt),
3558 bool_cond_p, cs->outside_range_p);
3559
3560 /* For the benefit of block_may_fallthru remember if the switch body
3561 case labels cover all possible values and if there are break; stmts. */
3562 if (cs->has_default_p
3563 || (!processing_template_decl
3564 && c_switch_covers_all_cases_p (cs->cases,
3565 SWITCH_STMT_TYPE (cs->switch_stmt))))
3566 SWITCH_STMT_ALL_CASES_P (cs->switch_stmt) = 1;
3567 if (!cs->break_stmt_seen_p)
3568 SWITCH_STMT_NO_BREAK_P (cs->switch_stmt) = 1;
3569 gcc_assert (!cs->in_loop_body_p);
3570 splay_tree_delete (cs->cases);
3571 switch_stack = switch_stack->next;
3572 free (cs);
3573 }
3574
3575 /* Note that a BREAK_STMT is about to be added. If it is inside of
3576 a SWITCH_STMT and not inside of a loop body inside of it, note
3577 in switch_stack we've seen a BREAK_STMT. */
3578
3579 void
note_break_stmt(void)3580 note_break_stmt (void)
3581 {
3582 if (switch_stack && !switch_stack->in_loop_body_p)
3583 switch_stack->break_stmt_seen_p = true;
3584 }
3585
3586 /* Note the start of processing of an iteration statement's body.
3587 The note_break_stmt function will do nothing while processing it.
3588 Return a flag that should be passed to note_iteration_stmt_body_end. */
3589
3590 bool
note_iteration_stmt_body_start(void)3591 note_iteration_stmt_body_start (void)
3592 {
3593 if (!switch_stack)
3594 return false;
3595 bool ret = switch_stack->in_loop_body_p;
3596 switch_stack->in_loop_body_p = true;
3597 return ret;
3598 }
3599
3600 /* Note the end of processing of an iteration statement's body. */
3601
3602 void
note_iteration_stmt_body_end(bool prev)3603 note_iteration_stmt_body_end (bool prev)
3604 {
3605 if (switch_stack)
3606 switch_stack->in_loop_body_p = prev;
3607 }
3608
3609 /* Convert a case constant VALUE in a switch to the type TYPE of the switch
3610 condition. Note that if TYPE and VALUE are already integral we don't
3611 really do the conversion because the language-independent
3612 warning/optimization code will work better that way. */
3613
3614 static tree
case_conversion(tree type,tree value)3615 case_conversion (tree type, tree value)
3616 {
3617 if (value == NULL_TREE)
3618 return value;
3619
3620 value = mark_rvalue_use (value);
3621
3622 if (cxx_dialect >= cxx11
3623 && (SCOPED_ENUM_P (type)
3624 || !INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (value))))
3625 {
3626 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
3627 type = type_promotes_to (type);
3628 value = (perform_implicit_conversion_flags
3629 (type, value, tf_warning_or_error,
3630 LOOKUP_IMPLICIT | LOOKUP_NO_NON_INTEGRAL));
3631 }
3632 return cxx_constant_value (value);
3633 }
3634
3635 /* Note that we've seen a definition of a case label, and complain if this
3636 is a bad place for one. */
3637
3638 tree
finish_case_label(location_t loc,tree low_value,tree high_value)3639 finish_case_label (location_t loc, tree low_value, tree high_value)
3640 {
3641 tree cond, r;
3642 cp_binding_level *p;
3643 tree type;
3644
3645 if (low_value == NULL_TREE && high_value == NULL_TREE)
3646 switch_stack->has_default_p = true;
3647
3648 if (processing_template_decl)
3649 {
3650 tree label;
3651
3652 /* For templates, just add the case label; we'll do semantic
3653 analysis at instantiation-time. */
3654 label = build_decl (loc, LABEL_DECL, NULL_TREE, NULL_TREE);
3655 return add_stmt (build_case_label (low_value, high_value, label));
3656 }
3657
3658 /* Find the condition on which this switch statement depends. */
3659 cond = SWITCH_STMT_COND (switch_stack->switch_stmt);
3660 if (cond && TREE_CODE (cond) == TREE_LIST)
3661 cond = TREE_VALUE (cond);
3662
3663 if (!check_switch_goto (switch_stack->level))
3664 return error_mark_node;
3665
3666 type = SWITCH_STMT_TYPE (switch_stack->switch_stmt);
3667
3668 low_value = case_conversion (type, low_value);
3669 high_value = case_conversion (type, high_value);
3670
3671 r = c_add_case_label (loc, switch_stack->cases, cond, type,
3672 low_value, high_value,
3673 &switch_stack->outside_range_p);
3674
3675 /* After labels, make any new cleanups in the function go into their
3676 own new (temporary) binding contour. */
3677 for (p = current_binding_level;
3678 p->kind != sk_function_parms;
3679 p = p->level_chain)
3680 p->more_cleanups_ok = 0;
3681
3682 return r;
3683 }
3684
3685 struct typename_info {
3686 tree scope;
3687 tree name;
3688 tree template_id;
3689 bool enum_p;
3690 bool class_p;
3691 };
3692
3693 struct typename_hasher : ggc_ptr_hash<tree_node>
3694 {
3695 typedef typename_info *compare_type;
3696
3697 /* Hash a TYPENAME_TYPE. */
3698
3699 static hashval_t
hashtypename_hasher3700 hash (tree t)
3701 {
3702 hashval_t hash;
3703
3704 hash = (htab_hash_pointer (TYPE_CONTEXT (t))
3705 ^ htab_hash_pointer (TYPE_IDENTIFIER (t)));
3706
3707 return hash;
3708 }
3709
3710 /* Compare two TYPENAME_TYPEs. */
3711
3712 static bool
equaltypename_hasher3713 equal (tree t1, const typename_info *t2)
3714 {
3715 return (TYPE_IDENTIFIER (t1) == t2->name
3716 && TYPE_CONTEXT (t1) == t2->scope
3717 && TYPENAME_TYPE_FULLNAME (t1) == t2->template_id
3718 && TYPENAME_IS_ENUM_P (t1) == t2->enum_p
3719 && TYPENAME_IS_CLASS_P (t1) == t2->class_p);
3720 }
3721 };
3722
3723 /* Build a TYPENAME_TYPE. If the type is `typename T::t', CONTEXT is
3724 the type of `T', NAME is the IDENTIFIER_NODE for `t'.
3725
3726 Returns the new TYPENAME_TYPE. */
3727
3728 static GTY (()) hash_table<typename_hasher> *typename_htab;
3729
3730 tree
build_typename_type(tree context,tree name,tree fullname,enum tag_types tag_type)3731 build_typename_type (tree context, tree name, tree fullname,
3732 enum tag_types tag_type)
3733 {
3734 tree t;
3735 tree d;
3736 typename_info ti;
3737 tree *e;
3738 hashval_t hash;
3739
3740 if (typename_htab == NULL)
3741 typename_htab = hash_table<typename_hasher>::create_ggc (61);
3742
3743 ti.scope = FROB_CONTEXT (context);
3744 ti.name = name;
3745 ti.template_id = fullname;
3746 ti.enum_p = tag_type == enum_type;
3747 ti.class_p = (tag_type == class_type
3748 || tag_type == record_type
3749 || tag_type == union_type);
3750 hash = (htab_hash_pointer (ti.scope)
3751 ^ htab_hash_pointer (ti.name));
3752
3753 /* See if we already have this type. */
3754 e = typename_htab->find_slot_with_hash (&ti, hash, INSERT);
3755 if (*e)
3756 t = *e;
3757 else
3758 {
3759 /* Build the TYPENAME_TYPE. */
3760 t = cxx_make_type (TYPENAME_TYPE);
3761 TYPE_CONTEXT (t) = ti.scope;
3762 TYPENAME_TYPE_FULLNAME (t) = ti.template_id;
3763 TYPENAME_IS_ENUM_P (t) = ti.enum_p;
3764 TYPENAME_IS_CLASS_P (t) = ti.class_p;
3765
3766 /* Build the corresponding TYPE_DECL. */
3767 d = build_decl (input_location, TYPE_DECL, name, t);
3768 TYPE_NAME (TREE_TYPE (d)) = d;
3769 TYPE_STUB_DECL (TREE_TYPE (d)) = d;
3770 DECL_CONTEXT (d) = FROB_CONTEXT (context);
3771 DECL_ARTIFICIAL (d) = 1;
3772
3773 /* Store it in the hash table. */
3774 *e = t;
3775
3776 /* TYPENAME_TYPEs must always be compared structurally, because
3777 they may or may not resolve down to another type depending on
3778 the currently open classes. */
3779 SET_TYPE_STRUCTURAL_EQUALITY (t);
3780 }
3781
3782 return t;
3783 }
3784
3785 /* Resolve `typename CONTEXT::NAME'. TAG_TYPE indicates the tag
3786 provided to name the type. Returns an appropriate type, unless an
3787 error occurs, in which case error_mark_node is returned. If we
3788 locate a non-artificial TYPE_DECL and TF_KEEP_TYPE_DECL is set, we
3789 return that, rather than the _TYPE it corresponds to, in other
3790 cases we look through the type decl. If TF_ERROR is set, complain
3791 about errors, otherwise be quiet. */
3792
3793 tree
make_typename_type(tree context,tree name,enum tag_types tag_type,tsubst_flags_t complain)3794 make_typename_type (tree context, tree name, enum tag_types tag_type,
3795 tsubst_flags_t complain)
3796 {
3797 tree fullname;
3798 tree t;
3799 bool want_template;
3800
3801 if (name == error_mark_node
3802 || context == NULL_TREE
3803 || context == error_mark_node)
3804 return error_mark_node;
3805
3806 if (TYPE_P (name))
3807 {
3808 if (!(TYPE_LANG_SPECIFIC (name)
3809 && (CLASSTYPE_IS_TEMPLATE (name)
3810 || CLASSTYPE_USE_TEMPLATE (name))))
3811 name = TYPE_IDENTIFIER (name);
3812 else
3813 /* Create a TEMPLATE_ID_EXPR for the type. */
3814 name = build_nt (TEMPLATE_ID_EXPR,
3815 CLASSTYPE_TI_TEMPLATE (name),
3816 CLASSTYPE_TI_ARGS (name));
3817 }
3818 else if (TREE_CODE (name) == TYPE_DECL)
3819 name = DECL_NAME (name);
3820
3821 fullname = name;
3822
3823 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
3824 {
3825 name = TREE_OPERAND (name, 0);
3826 if (DECL_TYPE_TEMPLATE_P (name))
3827 name = TREE_OPERAND (fullname, 0) = DECL_NAME (name);
3828 if (TREE_CODE (name) != IDENTIFIER_NODE)
3829 {
3830 if (complain & tf_error)
3831 error ("%qD is not a type", name);
3832 return error_mark_node;
3833 }
3834 }
3835 if (TREE_CODE (name) == TEMPLATE_DECL)
3836 {
3837 if (complain & tf_error)
3838 error ("%qD used without template parameters", name);
3839 return error_mark_node;
3840 }
3841 gcc_assert (identifier_p (name));
3842 gcc_assert (TYPE_P (context));
3843
3844 if (!MAYBE_CLASS_TYPE_P (context))
3845 {
3846 if (complain & tf_error)
3847 error ("%q#T is not a class", context);
3848 return error_mark_node;
3849 }
3850
3851 /* When the CONTEXT is a dependent type, NAME could refer to a
3852 dependent base class of CONTEXT. But look inside it anyway
3853 if CONTEXT is a currently open scope, in case it refers to a
3854 member of the current instantiation or a non-dependent base;
3855 lookup will stop when we hit a dependent base. */
3856 if (!dependent_scope_p (context))
3857 /* We should only set WANT_TYPE when we're a nested typename type.
3858 Then we can give better diagnostics if we find a non-type. */
3859 t = lookup_field (context, name, 2, /*want_type=*/true);
3860 else
3861 t = NULL_TREE;
3862
3863 if ((!t || TREE_CODE (t) == TREE_LIST) && dependent_type_p (context))
3864 return build_typename_type (context, name, fullname, tag_type);
3865
3866 want_template = TREE_CODE (fullname) == TEMPLATE_ID_EXPR;
3867
3868 if (!t)
3869 {
3870 if (complain & tf_error)
3871 {
3872 if (!COMPLETE_TYPE_P (context))
3873 cxx_incomplete_type_error (NULL_TREE, context);
3874 else
3875 error (want_template ? G_("no class template named %q#T in %q#T")
3876 : G_("no type named %q#T in %q#T"), name, context);
3877 }
3878 return error_mark_node;
3879 }
3880
3881 /* Pull out the template from an injected-class-name (or multiple). */
3882 if (want_template)
3883 t = maybe_get_template_decl_from_type_decl (t);
3884
3885 if (TREE_CODE (t) == TREE_LIST)
3886 {
3887 if (complain & tf_error)
3888 {
3889 error ("lookup of %qT in %qT is ambiguous", name, context);
3890 print_candidates (t);
3891 }
3892 return error_mark_node;
3893 }
3894
3895 if (want_template && !DECL_TYPE_TEMPLATE_P (t))
3896 {
3897 if (complain & tf_error)
3898 error ("%<typename %T::%D%> names %q#T, which is not a class template",
3899 context, name, t);
3900 return error_mark_node;
3901 }
3902 if (!want_template && TREE_CODE (t) != TYPE_DECL)
3903 {
3904 if (complain & tf_error)
3905 error ("%<typename %T::%D%> names %q#T, which is not a type",
3906 context, name, t);
3907 return error_mark_node;
3908 }
3909
3910 if (!perform_or_defer_access_check (TYPE_BINFO (context), t, t, complain))
3911 return error_mark_node;
3912
3913 /* If we are currently parsing a template and if T is a typedef accessed
3914 through CONTEXT then we need to remember and check access of T at
3915 template instantiation time. */
3916 add_typedef_to_current_template_for_access_check (t, context, input_location);
3917
3918 if (want_template)
3919 return lookup_template_class (t, TREE_OPERAND (fullname, 1),
3920 NULL_TREE, context,
3921 /*entering_scope=*/0,
3922 complain | tf_user);
3923
3924 if (DECL_ARTIFICIAL (t) || !(complain & tf_keep_type_decl))
3925 t = TREE_TYPE (t);
3926
3927 maybe_record_typedef_use (t);
3928
3929 return t;
3930 }
3931
3932 /* Resolve `CONTEXT::template NAME'. Returns a TEMPLATE_DECL if the name
3933 can be resolved or an UNBOUND_CLASS_TEMPLATE, unless an error occurs,
3934 in which case error_mark_node is returned.
3935
3936 If PARM_LIST is non-NULL, also make sure that the template parameter
3937 list of TEMPLATE_DECL matches.
3938
3939 If COMPLAIN zero, don't complain about any errors that occur. */
3940
3941 tree
make_unbound_class_template(tree context,tree name,tree parm_list,tsubst_flags_t complain)3942 make_unbound_class_template (tree context, tree name, tree parm_list,
3943 tsubst_flags_t complain)
3944 {
3945 tree t;
3946 tree d;
3947
3948 if (TYPE_P (name))
3949 name = TYPE_IDENTIFIER (name);
3950 else if (DECL_P (name))
3951 name = DECL_NAME (name);
3952 gcc_assert (identifier_p (name));
3953
3954 if (!dependent_type_p (context)
3955 || currently_open_class (context))
3956 {
3957 tree tmpl = NULL_TREE;
3958
3959 if (MAYBE_CLASS_TYPE_P (context))
3960 tmpl = lookup_field (context, name, 0, false);
3961
3962 if (tmpl && TREE_CODE (tmpl) == TYPE_DECL)
3963 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
3964
3965 if (!tmpl || !DECL_TYPE_TEMPLATE_P (tmpl))
3966 {
3967 if (complain & tf_error)
3968 error ("no class template named %q#T in %q#T", name, context);
3969 return error_mark_node;
3970 }
3971
3972 if (parm_list
3973 && !comp_template_parms (DECL_TEMPLATE_PARMS (tmpl), parm_list))
3974 {
3975 if (complain & tf_error)
3976 {
3977 error ("template parameters do not match template %qD", tmpl);
3978 inform (DECL_SOURCE_LOCATION (tmpl),
3979 "%qD declared here", tmpl);
3980 }
3981 return error_mark_node;
3982 }
3983
3984 if (!perform_or_defer_access_check (TYPE_BINFO (context), tmpl, tmpl,
3985 complain))
3986 return error_mark_node;
3987
3988 return tmpl;
3989 }
3990
3991 /* Build the UNBOUND_CLASS_TEMPLATE. */
3992 t = cxx_make_type (UNBOUND_CLASS_TEMPLATE);
3993 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
3994 TREE_TYPE (t) = NULL_TREE;
3995 SET_TYPE_STRUCTURAL_EQUALITY (t);
3996
3997 /* Build the corresponding TEMPLATE_DECL. */
3998 d = build_decl (input_location, TEMPLATE_DECL, name, t);
3999 TYPE_NAME (TREE_TYPE (d)) = d;
4000 TYPE_STUB_DECL (TREE_TYPE (d)) = d;
4001 DECL_CONTEXT (d) = FROB_CONTEXT (context);
4002 DECL_ARTIFICIAL (d) = 1;
4003 DECL_TEMPLATE_PARMS (d) = parm_list;
4004
4005 return t;
4006 }
4007
4008
4009
4010 /* Push the declarations of builtin types into the global namespace.
4011 RID_INDEX is the index of the builtin type in the array
4012 RID_POINTERS. NAME is the name used when looking up the builtin
4013 type. TYPE is the _TYPE node for the builtin type.
4014
4015 The calls to set_global_binding below should be
4016 eliminated. Built-in types should not be looked up name; their
4017 names are keywords that the parser can recognize. However, there
4018 is code in c-common.c that uses identifier_global_value to look up
4019 built-in types by name. */
4020
4021 void
record_builtin_type(enum rid rid_index,const char * name,tree type)4022 record_builtin_type (enum rid rid_index,
4023 const char* name,
4024 tree type)
4025 {
4026 tree decl = NULL_TREE;
4027
4028 if (name)
4029 {
4030 tree tname = get_identifier (name);
4031 tree tdecl = build_decl (BUILTINS_LOCATION, TYPE_DECL, tname, type);
4032 DECL_ARTIFICIAL (tdecl) = 1;
4033 set_global_binding (tdecl);
4034 decl = tdecl;
4035 }
4036
4037 if ((int) rid_index < (int) RID_MAX)
4038 if (tree rname = ridpointers[(int) rid_index])
4039 if (!decl || DECL_NAME (decl) != rname)
4040 {
4041 tree rdecl = build_decl (BUILTINS_LOCATION, TYPE_DECL, rname, type);
4042 DECL_ARTIFICIAL (rdecl) = 1;
4043 set_global_binding (rdecl);
4044 if (!decl)
4045 decl = rdecl;
4046 }
4047
4048 if (decl)
4049 {
4050 if (!TYPE_NAME (type))
4051 TYPE_NAME (type) = decl;
4052 debug_hooks->type_decl (decl, 0);
4053 }
4054 }
4055
4056 /* Push a type into the namespace so that the back ends ignore it. */
4057
4058 static void
record_unknown_type(tree type,const char * name)4059 record_unknown_type (tree type, const char* name)
4060 {
4061 tree decl = pushdecl (build_decl (UNKNOWN_LOCATION,
4062 TYPE_DECL, get_identifier (name), type));
4063 /* Make sure the "unknown type" typedecl gets ignored for debug info. */
4064 DECL_IGNORED_P (decl) = 1;
4065 TYPE_DECL_SUPPRESS_DEBUG (decl) = 1;
4066 TYPE_SIZE (type) = TYPE_SIZE (void_type_node);
4067 SET_TYPE_ALIGN (type, 1);
4068 TYPE_USER_ALIGN (type) = 0;
4069 SET_TYPE_MODE (type, TYPE_MODE (void_type_node));
4070 }
4071
4072 /* Create all the predefined identifiers. */
4073
4074 static void
initialize_predefined_identifiers(void)4075 initialize_predefined_identifiers (void)
4076 {
4077 struct predefined_identifier
4078 {
4079 const char *name; /* Name. */
4080 tree *node; /* Node to store it in. */
4081 cp_identifier_kind kind; /* Kind of identifier. */
4082 };
4083
4084 /* A table of identifiers to create at startup. */
4085 static const predefined_identifier predefined_identifiers[] = {
4086 {"C++", &lang_name_cplusplus, cik_normal},
4087 {"C", &lang_name_c, cik_normal},
4088 /* Some of these names have a trailing space so that it is
4089 impossible for them to conflict with names written by users. */
4090 {"__ct ", &ctor_identifier, cik_ctor},
4091 {"__ct_base ", &base_ctor_identifier, cik_ctor},
4092 {"__ct_comp ", &complete_ctor_identifier, cik_ctor},
4093 {"__dt ", &dtor_identifier, cik_dtor},
4094 {"__dt_base ", &base_dtor_identifier, cik_dtor},
4095 {"__dt_comp ", &complete_dtor_identifier, cik_dtor},
4096 {"__dt_del ", &deleting_dtor_identifier, cik_dtor},
4097 {"__conv_op ", &conv_op_identifier, cik_conv_op},
4098 {"__in_chrg", &in_charge_identifier, cik_normal},
4099 {"this", &this_identifier, cik_normal},
4100 {"__delta", &delta_identifier, cik_normal},
4101 {"__pfn", &pfn_identifier, cik_normal},
4102 {"_vptr", &vptr_identifier, cik_normal},
4103 {"__vtt_parm", &vtt_parm_identifier, cik_normal},
4104 {"::", &global_identifier, cik_normal},
4105 {"std", &std_identifier, cik_normal},
4106 /* The demangler expects anonymous namespaces to be called
4107 something starting with '_GLOBAL__N_'. It no longer needs
4108 to be unique to the TU. */
4109 {"_GLOBAL__N_1", &anon_identifier, cik_normal},
4110 {"auto", &auto_identifier, cik_normal},
4111 {"decltype(auto)", &decltype_auto_identifier, cik_normal},
4112 {"initializer_list", &init_list_identifier, cik_normal},
4113 {NULL, NULL, cik_normal}
4114 };
4115
4116 for (const predefined_identifier *pid = predefined_identifiers;
4117 pid->name; ++pid)
4118 {
4119 *pid->node = get_identifier (pid->name);
4120 /* Some of these identifiers already have a special kind. */
4121 if (pid->kind != cik_normal)
4122 set_identifier_kind (*pid->node, pid->kind);
4123 }
4124 }
4125
4126 /* Create the predefined scalar types of C,
4127 and some nodes representing standard constants (0, 1, (void *)0).
4128 Initialize the global binding level.
4129 Make definitions for built-in primitive functions. */
4130
4131 void
cxx_init_decl_processing(void)4132 cxx_init_decl_processing (void)
4133 {
4134 tree void_ftype;
4135 tree void_ftype_ptr;
4136
4137 /* Create all the identifiers we need. */
4138 initialize_predefined_identifiers ();
4139
4140 /* Create the global variables. */
4141 push_to_top_level ();
4142
4143 current_function_decl = NULL_TREE;
4144 current_binding_level = NULL;
4145 /* Enter the global namespace. */
4146 gcc_assert (global_namespace == NULL_TREE);
4147 global_namespace = build_lang_decl (NAMESPACE_DECL, global_identifier,
4148 void_type_node);
4149 TREE_PUBLIC (global_namespace) = 1;
4150 DECL_CONTEXT (global_namespace)
4151 = build_translation_unit_decl (get_identifier (main_input_filename));
4152 /* Remember whether we want the empty class passing ABI change warning
4153 in this TU. */
4154 TRANSLATION_UNIT_WARN_EMPTY_P (DECL_CONTEXT (global_namespace))
4155 = warn_abi && abi_version_crosses (12);
4156 debug_hooks->register_main_translation_unit
4157 (DECL_CONTEXT (global_namespace));
4158 begin_scope (sk_namespace, global_namespace);
4159 current_namespace = global_namespace;
4160
4161 if (flag_visibility_ms_compat)
4162 default_visibility = VISIBILITY_HIDDEN;
4163
4164 /* Initially, C. */
4165 current_lang_name = lang_name_c;
4166
4167 /* Create the `std' namespace. */
4168 push_namespace (std_identifier);
4169 std_node = current_namespace;
4170 pop_namespace ();
4171
4172 flag_noexcept_type = (cxx_dialect >= cxx17);
4173 /* There's no fixed location for <command-line>, the current
4174 location is <builtins>, which is somewhat confusing. */
4175 if (!flag_new_for_scope)
4176 warning_at (UNKNOWN_LOCATION, OPT_Wdeprecated,
4177 "%<-fno-for-scope%> is deprecated");
4178 if (flag_friend_injection)
4179 warning_at (UNKNOWN_LOCATION, OPT_Wdeprecated,
4180 "%<-ffriend-injection%> is deprecated");
4181
4182 c_common_nodes_and_builtins ();
4183
4184 integer_two_node = build_int_cst (NULL_TREE, 2);
4185
4186 /* Guess at the initial static decls size. */
4187 vec_alloc (static_decls, 500);
4188
4189 /* ... and keyed classes. */
4190 vec_alloc (keyed_classes, 100);
4191
4192 record_builtin_type (RID_BOOL, "bool", boolean_type_node);
4193 truthvalue_type_node = boolean_type_node;
4194 truthvalue_false_node = boolean_false_node;
4195 truthvalue_true_node = boolean_true_node;
4196
4197 empty_except_spec = build_tree_list (NULL_TREE, NULL_TREE);
4198 noexcept_true_spec = build_tree_list (boolean_true_node, NULL_TREE);
4199 noexcept_false_spec = build_tree_list (boolean_false_node, NULL_TREE);
4200 noexcept_deferred_spec = build_tree_list (make_node (DEFERRED_NOEXCEPT),
4201 NULL_TREE);
4202
4203 #if 0
4204 record_builtin_type (RID_MAX, NULL, string_type_node);
4205 #endif
4206
4207 delta_type_node = ptrdiff_type_node;
4208 vtable_index_type = ptrdiff_type_node;
4209
4210 vtt_parm_type = build_pointer_type (const_ptr_type_node);
4211 void_ftype = build_function_type_list (void_type_node, NULL_TREE);
4212 void_ftype_ptr = build_function_type_list (void_type_node,
4213 ptr_type_node, NULL_TREE);
4214 void_ftype_ptr
4215 = build_exception_variant (void_ftype_ptr, empty_except_spec);
4216
4217 /* Create the conversion operator marker. This operator's DECL_NAME
4218 is in the identifier table, so we can use identifier equality to
4219 find it. */
4220 conv_op_marker = build_lang_decl (FUNCTION_DECL, conv_op_identifier,
4221 void_ftype);
4222
4223 /* C++ extensions */
4224
4225 unknown_type_node = make_node (LANG_TYPE);
4226 record_unknown_type (unknown_type_node, "unknown type");
4227
4228 /* Indirecting an UNKNOWN_TYPE node yields an UNKNOWN_TYPE node. */
4229 TREE_TYPE (unknown_type_node) = unknown_type_node;
4230
4231 /* Looking up TYPE_POINTER_TO and TYPE_REFERENCE_TO yield the same
4232 result. */
4233 TYPE_POINTER_TO (unknown_type_node) = unknown_type_node;
4234 TYPE_REFERENCE_TO (unknown_type_node) = unknown_type_node;
4235
4236 init_list_type_node = make_node (LANG_TYPE);
4237 record_unknown_type (init_list_type_node, "init list");
4238
4239 {
4240 /* Make sure we get a unique function type, so we can give
4241 its pointer type a name. (This wins for gdb.) */
4242 tree vfunc_type = make_node (FUNCTION_TYPE);
4243 TREE_TYPE (vfunc_type) = integer_type_node;
4244 TYPE_ARG_TYPES (vfunc_type) = NULL_TREE;
4245 layout_type (vfunc_type);
4246
4247 vtable_entry_type = build_pointer_type (vfunc_type);
4248 }
4249 record_builtin_type (RID_MAX, "__vtbl_ptr_type", vtable_entry_type);
4250
4251 vtbl_type_node
4252 = build_cplus_array_type (vtable_entry_type, NULL_TREE);
4253 layout_type (vtbl_type_node);
4254 vtbl_type_node = cp_build_qualified_type (vtbl_type_node, TYPE_QUAL_CONST);
4255 record_builtin_type (RID_MAX, NULL, vtbl_type_node);
4256 vtbl_ptr_type_node = build_pointer_type (vtable_entry_type);
4257 layout_type (vtbl_ptr_type_node);
4258 record_builtin_type (RID_MAX, NULL, vtbl_ptr_type_node);
4259
4260 push_namespace (get_identifier ("__cxxabiv1"));
4261 abi_node = current_namespace;
4262 pop_namespace ();
4263
4264 global_type_node = make_node (LANG_TYPE);
4265 record_unknown_type (global_type_node, "global type");
4266
4267 any_targ_node = make_node (LANG_TYPE);
4268 record_unknown_type (any_targ_node, "any type");
4269
4270 /* Now, C++. */
4271 current_lang_name = lang_name_cplusplus;
4272
4273 if (aligned_new_threshold > 1
4274 && !pow2p_hwi (aligned_new_threshold))
4275 {
4276 error ("-faligned-new=%d is not a power of two", aligned_new_threshold);
4277 aligned_new_threshold = 1;
4278 }
4279 if (aligned_new_threshold == -1)
4280 aligned_new_threshold = (cxx_dialect >= cxx17) ? 1 : 0;
4281 if (aligned_new_threshold == 1)
4282 aligned_new_threshold = malloc_alignment () / BITS_PER_UNIT;
4283
4284 {
4285 tree newattrs, extvisattr;
4286 tree newtype, deltype;
4287 tree ptr_ftype_sizetype;
4288 tree new_eh_spec;
4289
4290 ptr_ftype_sizetype
4291 = build_function_type_list (ptr_type_node, size_type_node, NULL_TREE);
4292 if (cxx_dialect == cxx98)
4293 {
4294 tree bad_alloc_id;
4295 tree bad_alloc_type_node;
4296 tree bad_alloc_decl;
4297
4298 push_namespace (std_identifier);
4299 bad_alloc_id = get_identifier ("bad_alloc");
4300 bad_alloc_type_node = make_class_type (RECORD_TYPE);
4301 TYPE_CONTEXT (bad_alloc_type_node) = current_namespace;
4302 bad_alloc_decl
4303 = create_implicit_typedef (bad_alloc_id, bad_alloc_type_node);
4304 DECL_CONTEXT (bad_alloc_decl) = current_namespace;
4305 pop_namespace ();
4306
4307 new_eh_spec
4308 = add_exception_specifier (NULL_TREE, bad_alloc_type_node, -1);
4309 }
4310 else
4311 new_eh_spec = noexcept_false_spec;
4312
4313 /* Ensure attribs.c is initialized. */
4314 init_attributes ();
4315
4316 /* Ensure constraint.cc is initialized. */
4317 init_constraint_processing ();
4318
4319 extvisattr = build_tree_list (get_identifier ("externally_visible"),
4320 NULL_TREE);
4321 newattrs = tree_cons (get_identifier ("alloc_size"),
4322 build_tree_list (NULL_TREE, integer_one_node),
4323 extvisattr);
4324 newtype = cp_build_type_attribute_variant (ptr_ftype_sizetype, newattrs);
4325 newtype = build_exception_variant (newtype, new_eh_spec);
4326 deltype = cp_build_type_attribute_variant (void_ftype_ptr, extvisattr);
4327 deltype = build_exception_variant (deltype, empty_except_spec);
4328 tree opnew = push_cp_library_fn (NEW_EXPR, newtype, 0);
4329 DECL_IS_MALLOC (opnew) = 1;
4330 DECL_IS_OPERATOR_NEW (opnew) = 1;
4331 opnew = push_cp_library_fn (VEC_NEW_EXPR, newtype, 0);
4332 DECL_IS_MALLOC (opnew) = 1;
4333 DECL_IS_OPERATOR_NEW (opnew) = 1;
4334 push_cp_library_fn (DELETE_EXPR, deltype, ECF_NOTHROW);
4335 push_cp_library_fn (VEC_DELETE_EXPR, deltype, ECF_NOTHROW);
4336 if (flag_sized_deallocation)
4337 {
4338 /* Also push the sized deallocation variants:
4339 void operator delete(void*, std::size_t) throw();
4340 void operator delete[](void*, std::size_t) throw(); */
4341 tree void_ftype_ptr_size
4342 = build_function_type_list (void_type_node, ptr_type_node,
4343 size_type_node, NULL_TREE);
4344 deltype = cp_build_type_attribute_variant (void_ftype_ptr_size,
4345 extvisattr);
4346 deltype = build_exception_variant (deltype, empty_except_spec);
4347 push_cp_library_fn (DELETE_EXPR, deltype, ECF_NOTHROW);
4348 push_cp_library_fn (VEC_DELETE_EXPR, deltype, ECF_NOTHROW);
4349 }
4350
4351 if (aligned_new_threshold)
4352 {
4353 push_namespace (std_identifier);
4354 tree align_id = get_identifier ("align_val_t");
4355 align_type_node = start_enum (align_id, NULL_TREE, size_type_node,
4356 NULL_TREE, /*scoped*/true, NULL);
4357 pop_namespace ();
4358
4359 /* operator new (size_t, align_val_t); */
4360 newtype = build_function_type_list (ptr_type_node, size_type_node,
4361 align_type_node, NULL_TREE);
4362 newtype = cp_build_type_attribute_variant (newtype, newattrs);
4363 newtype = build_exception_variant (newtype, new_eh_spec);
4364 opnew = push_cp_library_fn (NEW_EXPR, newtype, 0);
4365 DECL_IS_MALLOC (opnew) = 1;
4366 DECL_IS_OPERATOR_NEW (opnew) = 1;
4367 opnew = push_cp_library_fn (VEC_NEW_EXPR, newtype, 0);
4368 DECL_IS_MALLOC (opnew) = 1;
4369 DECL_IS_OPERATOR_NEW (opnew) = 1;
4370
4371 /* operator delete (void *, align_val_t); */
4372 deltype = build_function_type_list (void_type_node, ptr_type_node,
4373 align_type_node, NULL_TREE);
4374 deltype = cp_build_type_attribute_variant (deltype, extvisattr);
4375 deltype = build_exception_variant (deltype, empty_except_spec);
4376 push_cp_library_fn (DELETE_EXPR, deltype, ECF_NOTHROW);
4377 push_cp_library_fn (VEC_DELETE_EXPR, deltype, ECF_NOTHROW);
4378
4379 if (flag_sized_deallocation)
4380 {
4381 /* operator delete (void *, size_t, align_val_t); */
4382 deltype = build_function_type_list (void_type_node, ptr_type_node,
4383 size_type_node, align_type_node,
4384 NULL_TREE);
4385 deltype = cp_build_type_attribute_variant (deltype, extvisattr);
4386 deltype = build_exception_variant (deltype, empty_except_spec);
4387 push_cp_library_fn (DELETE_EXPR, deltype, ECF_NOTHROW);
4388 push_cp_library_fn (VEC_DELETE_EXPR, deltype, ECF_NOTHROW);
4389 }
4390 }
4391
4392 nullptr_type_node = make_node (NULLPTR_TYPE);
4393 TYPE_SIZE (nullptr_type_node) = bitsize_int (GET_MODE_BITSIZE (ptr_mode));
4394 TYPE_SIZE_UNIT (nullptr_type_node) = size_int (GET_MODE_SIZE (ptr_mode));
4395 TYPE_UNSIGNED (nullptr_type_node) = 1;
4396 TYPE_PRECISION (nullptr_type_node) = GET_MODE_BITSIZE (ptr_mode);
4397 if (abi_version_at_least (9))
4398 SET_TYPE_ALIGN (nullptr_type_node, GET_MODE_ALIGNMENT (ptr_mode));
4399 SET_TYPE_MODE (nullptr_type_node, ptr_mode);
4400 record_builtin_type (RID_MAX, "decltype(nullptr)", nullptr_type_node);
4401 nullptr_node = build_int_cst (nullptr_type_node, 0);
4402 }
4403
4404 abort_fndecl
4405 = build_library_fn_ptr ("__cxa_pure_virtual", void_ftype,
4406 ECF_NORETURN | ECF_NOTHROW | ECF_COLD);
4407
4408 /* Perform other language dependent initializations. */
4409 init_class_processing ();
4410 init_rtti_processing ();
4411 init_template_processing ();
4412
4413 if (flag_exceptions)
4414 init_exception_processing ();
4415
4416 if (! supports_one_only ())
4417 flag_weak = 0;
4418
4419 make_fname_decl = cp_make_fname_decl;
4420 start_fname_decls ();
4421
4422 /* Show we use EH for cleanups. */
4423 if (flag_exceptions)
4424 using_eh_for_cleanups ();
4425 }
4426
4427 /* Generate an initializer for a function naming variable from
4428 NAME. NAME may be NULL, to indicate a dependent name. TYPE_P is
4429 filled in with the type of the init. */
4430
4431 tree
cp_fname_init(const char * name,tree * type_p)4432 cp_fname_init (const char* name, tree *type_p)
4433 {
4434 tree domain = NULL_TREE;
4435 tree type;
4436 tree init = NULL_TREE;
4437 size_t length = 0;
4438
4439 if (name)
4440 {
4441 length = strlen (name);
4442 domain = build_index_type (size_int (length));
4443 init = build_string (length + 1, name);
4444 }
4445
4446 type = cp_build_qualified_type (char_type_node, TYPE_QUAL_CONST);
4447 type = build_cplus_array_type (type, domain);
4448
4449 *type_p = type;
4450
4451 if (init)
4452 TREE_TYPE (init) = type;
4453 else
4454 init = error_mark_node;
4455
4456 return init;
4457 }
4458
4459 /* Create the VAR_DECL for __FUNCTION__ etc. ID is the name to give
4460 the decl, LOC is the location to give the decl, NAME is the
4461 initialization string and TYPE_DEP indicates whether NAME depended
4462 on the type of the function. We make use of that to detect
4463 __PRETTY_FUNCTION__ inside a template fn. This is being done lazily
4464 at the point of first use, so we mustn't push the decl now. */
4465
4466 static tree
cp_make_fname_decl(location_t loc,tree id,int type_dep)4467 cp_make_fname_decl (location_t loc, tree id, int type_dep)
4468 {
4469 const char *const name = (type_dep && processing_template_decl
4470 ? NULL : fname_as_string (type_dep));
4471 tree type;
4472 tree init = cp_fname_init (name, &type);
4473 tree decl = build_decl (loc, VAR_DECL, id, type);
4474
4475 if (name)
4476 free (CONST_CAST (char *, name));
4477
4478 TREE_STATIC (decl) = 1;
4479 TREE_READONLY (decl) = 1;
4480 DECL_ARTIFICIAL (decl) = 1;
4481
4482 TREE_USED (decl) = 1;
4483
4484 if (current_function_decl)
4485 {
4486 DECL_CONTEXT (decl) = current_function_decl;
4487 decl = pushdecl_outermost_localscope (decl);
4488 cp_finish_decl (decl, init, /*init_const_expr_p=*/false, NULL_TREE,
4489 LOOKUP_ONLYCONVERTING);
4490 }
4491 else
4492 {
4493 DECL_THIS_STATIC (decl) = true;
4494 pushdecl_top_level_and_finish (decl, init);
4495 }
4496
4497 return decl;
4498 }
4499
4500 static tree
builtin_function_1(tree decl,tree context,bool is_global)4501 builtin_function_1 (tree decl, tree context, bool is_global)
4502 {
4503 tree id = DECL_NAME (decl);
4504 const char *name = IDENTIFIER_POINTER (id);
4505
4506 retrofit_lang_decl (decl);
4507
4508 DECL_ARTIFICIAL (decl) = 1;
4509 SET_DECL_LANGUAGE (decl, lang_c);
4510 /* Runtime library routines are, by definition, available in an
4511 external shared object. */
4512 DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT;
4513 DECL_VISIBILITY_SPECIFIED (decl) = 1;
4514
4515 DECL_CONTEXT (decl) = context;
4516
4517 /* A function in the user's namespace should have an explicit
4518 declaration before it is used. Mark the built-in function as
4519 anticipated but not actually declared. */
4520 if (name[0] != '_' || name[1] != '_')
4521 DECL_ANTICIPATED (decl) = 1;
4522 else if (strncmp (name + 2, "builtin_", strlen ("builtin_")) != 0)
4523 {
4524 size_t len = strlen (name);
4525
4526 /* Treat __*_chk fortification functions as anticipated as well,
4527 unless they are __builtin_*. */
4528 if (len > strlen ("___chk")
4529 && memcmp (name + len - strlen ("_chk"),
4530 "_chk", strlen ("_chk") + 1) == 0)
4531 DECL_ANTICIPATED (decl) = 1;
4532 }
4533
4534 if (is_global)
4535 pushdecl_top_level (decl);
4536 else
4537 pushdecl (decl);
4538
4539 return decl;
4540 }
4541
4542 tree
cxx_builtin_function(tree decl)4543 cxx_builtin_function (tree decl)
4544 {
4545 tree id = DECL_NAME (decl);
4546 const char *name = IDENTIFIER_POINTER (id);
4547 /* All builtins that don't begin with an '_' should additionally
4548 go in the 'std' namespace. */
4549 if (name[0] != '_')
4550 {
4551 tree decl2 = copy_node(decl);
4552 push_namespace (std_identifier);
4553 builtin_function_1 (decl2, std_node, false);
4554 pop_namespace ();
4555 }
4556
4557 return builtin_function_1 (decl, NULL_TREE, false);
4558 }
4559
4560 /* Like cxx_builtin_function, but guarantee the function is added to the global
4561 scope. This is to allow function specific options to add new machine
4562 dependent builtins when the target ISA changes via attribute((target(...)))
4563 which saves space on program startup if the program does not use non-generic
4564 ISAs. */
4565
4566 tree
cxx_builtin_function_ext_scope(tree decl)4567 cxx_builtin_function_ext_scope (tree decl)
4568 {
4569
4570 tree id = DECL_NAME (decl);
4571 const char *name = IDENTIFIER_POINTER (id);
4572 /* All builtins that don't begin with an '_' should additionally
4573 go in the 'std' namespace. */
4574 if (name[0] != '_')
4575 {
4576 tree decl2 = copy_node(decl);
4577 push_namespace (std_identifier);
4578 builtin_function_1 (decl2, std_node, true);
4579 pop_namespace ();
4580 }
4581
4582 return builtin_function_1 (decl, NULL_TREE, true);
4583 }
4584
4585 /* Generate a FUNCTION_DECL with the typical flags for a runtime library
4586 function. Not called directly. */
4587
4588 static tree
build_library_fn(tree name,enum tree_code operator_code,tree type,int ecf_flags)4589 build_library_fn (tree name, enum tree_code operator_code, tree type,
4590 int ecf_flags)
4591 {
4592 tree fn = build_lang_decl (FUNCTION_DECL, name, type);
4593 DECL_EXTERNAL (fn) = 1;
4594 TREE_PUBLIC (fn) = 1;
4595 DECL_ARTIFICIAL (fn) = 1;
4596 DECL_OVERLOADED_OPERATOR_CODE_RAW (fn)
4597 = OVL_OP_INFO (false, operator_code)->ovl_op_code;
4598 SET_DECL_LANGUAGE (fn, lang_c);
4599 /* Runtime library routines are, by definition, available in an
4600 external shared object. */
4601 DECL_VISIBILITY (fn) = VISIBILITY_DEFAULT;
4602 DECL_VISIBILITY_SPECIFIED (fn) = 1;
4603 set_call_expr_flags (fn, ecf_flags);
4604 return fn;
4605 }
4606
4607 /* Returns the _DECL for a library function with C++ linkage. */
4608
4609 static tree
build_cp_library_fn(tree name,enum tree_code operator_code,tree type,int ecf_flags)4610 build_cp_library_fn (tree name, enum tree_code operator_code, tree type,
4611 int ecf_flags)
4612 {
4613 tree fn = build_library_fn (name, operator_code, type, ecf_flags);
4614 DECL_CONTEXT (fn) = FROB_CONTEXT (current_namespace);
4615 SET_DECL_LANGUAGE (fn, lang_cplusplus);
4616 return fn;
4617 }
4618
4619 /* Like build_library_fn, but takes a C string instead of an
4620 IDENTIFIER_NODE. */
4621
4622 tree
build_library_fn_ptr(const char * name,tree type,int ecf_flags)4623 build_library_fn_ptr (const char* name, tree type, int ecf_flags)
4624 {
4625 return build_library_fn (get_identifier (name), ERROR_MARK, type, ecf_flags);
4626 }
4627
4628 /* Like build_cp_library_fn, but takes a C string instead of an
4629 IDENTIFIER_NODE. */
4630
4631 tree
build_cp_library_fn_ptr(const char * name,tree type,int ecf_flags)4632 build_cp_library_fn_ptr (const char* name, tree type, int ecf_flags)
4633 {
4634 return build_cp_library_fn (get_identifier (name), ERROR_MARK, type,
4635 ecf_flags);
4636 }
4637
4638 /* Like build_library_fn, but also pushes the function so that we will
4639 be able to find it via get_global_binding. Also, the function
4640 may throw exceptions listed in RAISES. */
4641
4642 tree
push_library_fn(tree name,tree type,tree raises,int ecf_flags)4643 push_library_fn (tree name, tree type, tree raises, int ecf_flags)
4644 {
4645 tree fn;
4646
4647 if (raises)
4648 type = build_exception_variant (type, raises);
4649
4650 fn = build_library_fn (name, ERROR_MARK, type, ecf_flags);
4651 pushdecl_top_level (fn);
4652 return fn;
4653 }
4654
4655 /* Like build_cp_library_fn, but also pushes the function so that it
4656 will be found by normal lookup. */
4657
4658 static tree
push_cp_library_fn(enum tree_code operator_code,tree type,int ecf_flags)4659 push_cp_library_fn (enum tree_code operator_code, tree type,
4660 int ecf_flags)
4661 {
4662 tree fn = build_cp_library_fn (ovl_op_identifier (false, operator_code),
4663 operator_code, type, ecf_flags);
4664 pushdecl (fn);
4665 if (flag_tm)
4666 apply_tm_attr (fn, get_identifier ("transaction_safe"));
4667 return fn;
4668 }
4669
4670 /* Like push_library_fn, but takes a TREE_LIST of parm types rather than
4671 a FUNCTION_TYPE. */
4672
4673 tree
push_void_library_fn(tree name,tree parmtypes,int ecf_flags)4674 push_void_library_fn (tree name, tree parmtypes, int ecf_flags)
4675 {
4676 tree type = build_function_type (void_type_node, parmtypes);
4677 return push_library_fn (name, type, NULL_TREE, ecf_flags);
4678 }
4679
4680 /* Like push_library_fn, but also note that this function throws
4681 and does not return. Used for __throw_foo and the like. */
4682
4683 tree
push_throw_library_fn(tree name,tree type)4684 push_throw_library_fn (tree name, tree type)
4685 {
4686 tree fn = push_library_fn (name, type, NULL_TREE, ECF_NORETURN | ECF_COLD);
4687 return fn;
4688 }
4689
4690 /* When we call finish_struct for an anonymous union, we create
4691 default copy constructors and such. But, an anonymous union
4692 shouldn't have such things; this function undoes the damage to the
4693 anonymous union type T.
4694
4695 (The reason that we create the synthesized methods is that we don't
4696 distinguish `union { int i; }' from `typedef union { int i; } U'.
4697 The first is an anonymous union; the second is just an ordinary
4698 union type.) */
4699
4700 void
fixup_anonymous_aggr(tree t)4701 fixup_anonymous_aggr (tree t)
4702 {
4703 /* Wipe out memory of synthesized methods. */
4704 TYPE_HAS_USER_CONSTRUCTOR (t) = 0;
4705 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 0;
4706 TYPE_HAS_COPY_CTOR (t) = 0;
4707 TYPE_HAS_CONST_COPY_CTOR (t) = 0;
4708 TYPE_HAS_COPY_ASSIGN (t) = 0;
4709 TYPE_HAS_CONST_COPY_ASSIGN (t) = 0;
4710
4711 /* Splice the implicitly generated functions out of TYPE_FIELDS. */
4712 for (tree probe, *prev_p = &TYPE_FIELDS (t); (probe = *prev_p);)
4713 if (TREE_CODE (probe) == FUNCTION_DECL && DECL_ARTIFICIAL (probe))
4714 *prev_p = DECL_CHAIN (probe);
4715 else
4716 prev_p = &DECL_CHAIN (probe);
4717
4718 /* Anonymous aggregates cannot have fields with ctors, dtors or complex
4719 assignment operators (because they cannot have these methods themselves).
4720 For anonymous unions this is already checked because they are not allowed
4721 in any union, otherwise we have to check it. */
4722 if (TREE_CODE (t) != UNION_TYPE)
4723 {
4724 tree field, type;
4725
4726 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
4727 if (TREE_CODE (field) == FIELD_DECL)
4728 {
4729 type = TREE_TYPE (field);
4730 if (CLASS_TYPE_P (type))
4731 {
4732 if (TYPE_NEEDS_CONSTRUCTING (type))
4733 error ("member %q+#D with constructor not allowed "
4734 "in anonymous aggregate", field);
4735 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4736 error ("member %q+#D with destructor not allowed "
4737 "in anonymous aggregate", field);
4738 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
4739 error ("member %q+#D with copy assignment operator "
4740 "not allowed in anonymous aggregate", field);
4741 }
4742 }
4743 }
4744 }
4745
4746 /* Warn for an attribute located at LOCATION that appertains to the
4747 class type CLASS_TYPE that has not been properly placed after its
4748 class-key, in it class-specifier. */
4749
4750 void
warn_misplaced_attr_for_class_type(source_location location,tree class_type)4751 warn_misplaced_attr_for_class_type (source_location location,
4752 tree class_type)
4753 {
4754 gcc_assert (OVERLOAD_TYPE_P (class_type));
4755
4756 if (warning_at (location, OPT_Wattributes,
4757 "attribute ignored in declaration "
4758 "of %q#T", class_type))
4759 inform (location,
4760 "attribute for %q#T must follow the %qs keyword",
4761 class_type, class_key_or_enum_as_string (class_type));
4762 }
4763
4764 /* Make sure that a declaration with no declarator is well-formed, i.e.
4765 just declares a tagged type or anonymous union.
4766
4767 Returns the type declared; or NULL_TREE if none. */
4768
4769 tree
check_tag_decl(cp_decl_specifier_seq * declspecs,bool explicit_type_instantiation_p)4770 check_tag_decl (cp_decl_specifier_seq *declspecs,
4771 bool explicit_type_instantiation_p)
4772 {
4773 int saw_friend = decl_spec_seq_has_spec_p (declspecs, ds_friend);
4774 int saw_typedef = decl_spec_seq_has_spec_p (declspecs, ds_typedef);
4775 /* If a class, struct, or enum type is declared by the DECLSPECS
4776 (i.e, if a class-specifier, enum-specifier, or non-typename
4777 elaborated-type-specifier appears in the DECLSPECS),
4778 DECLARED_TYPE is set to the corresponding type. */
4779 tree declared_type = NULL_TREE;
4780 bool error_p = false;
4781
4782 if (declspecs->multiple_types_p)
4783 error ("multiple types in one declaration");
4784 else if (declspecs->redefined_builtin_type)
4785 {
4786 if (!in_system_header_at (input_location))
4787 permerror (declspecs->locations[ds_redefined_builtin_type_spec],
4788 "redeclaration of C++ built-in type %qT",
4789 declspecs->redefined_builtin_type);
4790 return NULL_TREE;
4791 }
4792
4793 if (declspecs->type
4794 && TYPE_P (declspecs->type)
4795 && ((TREE_CODE (declspecs->type) != TYPENAME_TYPE
4796 && MAYBE_CLASS_TYPE_P (declspecs->type))
4797 || TREE_CODE (declspecs->type) == ENUMERAL_TYPE))
4798 declared_type = declspecs->type;
4799 else if (declspecs->type == error_mark_node)
4800 error_p = true;
4801 if (declared_type == NULL_TREE && ! saw_friend && !error_p)
4802 permerror (input_location, "declaration does not declare anything");
4803 else if (declared_type != NULL_TREE && type_uses_auto (declared_type))
4804 {
4805 error_at (declspecs->locations[ds_type_spec],
4806 "%<auto%> can only be specified for variables "
4807 "or function declarations");
4808 return error_mark_node;
4809 }
4810 /* Check for an anonymous union. */
4811 else if (declared_type && RECORD_OR_UNION_CODE_P (TREE_CODE (declared_type))
4812 && TYPE_UNNAMED_P (declared_type))
4813 {
4814 /* 7/3 In a simple-declaration, the optional init-declarator-list
4815 can be omitted only when declaring a class (clause 9) or
4816 enumeration (7.2), that is, when the decl-specifier-seq contains
4817 either a class-specifier, an elaborated-type-specifier with
4818 a class-key (9.1), or an enum-specifier. In these cases and
4819 whenever a class-specifier or enum-specifier is present in the
4820 decl-specifier-seq, the identifiers in these specifiers are among
4821 the names being declared by the declaration (as class-name,
4822 enum-names, or enumerators, depending on the syntax). In such
4823 cases, and except for the declaration of an unnamed bit-field (9.6),
4824 the decl-specifier-seq shall introduce one or more names into the
4825 program, or shall redeclare a name introduced by a previous
4826 declaration. [Example:
4827 enum { }; // ill-formed
4828 typedef class { }; // ill-formed
4829 --end example] */
4830 if (saw_typedef)
4831 {
4832 error ("missing type-name in typedef-declaration");
4833 return NULL_TREE;
4834 }
4835 /* Anonymous unions are objects, so they can have specifiers. */;
4836 SET_ANON_AGGR_TYPE_P (declared_type);
4837
4838 if (TREE_CODE (declared_type) != UNION_TYPE
4839 && !in_system_header_at (input_location))
4840 pedwarn (input_location, OPT_Wpedantic, "ISO C++ prohibits anonymous structs");
4841 }
4842
4843 else
4844 {
4845 if (decl_spec_seq_has_spec_p (declspecs, ds_inline))
4846 error_at (declspecs->locations[ds_inline],
4847 "%<inline%> can only be specified for functions");
4848 else if (decl_spec_seq_has_spec_p (declspecs, ds_virtual))
4849 error_at (declspecs->locations[ds_virtual],
4850 "%<virtual%> can only be specified for functions");
4851 else if (saw_friend
4852 && (!current_class_type
4853 || current_scope () != current_class_type))
4854 error_at (declspecs->locations[ds_friend],
4855 "%<friend%> can only be specified inside a class");
4856 else if (decl_spec_seq_has_spec_p (declspecs, ds_explicit))
4857 error_at (declspecs->locations[ds_explicit],
4858 "%<explicit%> can only be specified for constructors");
4859 else if (declspecs->storage_class)
4860 error_at (declspecs->locations[ds_storage_class],
4861 "a storage class can only be specified for objects "
4862 "and functions");
4863 else if (decl_spec_seq_has_spec_p (declspecs, ds_const))
4864 error_at (declspecs->locations[ds_const],
4865 "%<const%> can only be specified for objects and "
4866 "functions");
4867 else if (decl_spec_seq_has_spec_p (declspecs, ds_volatile))
4868 error_at (declspecs->locations[ds_volatile],
4869 "%<volatile%> can only be specified for objects and "
4870 "functions");
4871 else if (decl_spec_seq_has_spec_p (declspecs, ds_restrict))
4872 error_at (declspecs->locations[ds_restrict],
4873 "%<__restrict%> can only be specified for objects and "
4874 "functions");
4875 else if (decl_spec_seq_has_spec_p (declspecs, ds_thread))
4876 error_at (declspecs->locations[ds_thread],
4877 "%<__thread%> can only be specified for objects "
4878 "and functions");
4879 else if (saw_typedef)
4880 warning_at (declspecs->locations[ds_typedef], 0,
4881 "%<typedef%> was ignored in this declaration");
4882 else if (decl_spec_seq_has_spec_p (declspecs, ds_constexpr))
4883 error_at (declspecs->locations[ds_constexpr],
4884 "%<constexpr%> cannot be used for type declarations");
4885 }
4886
4887 if (declspecs->attributes && warn_attributes && declared_type)
4888 {
4889 location_t loc;
4890 if (!CLASS_TYPE_P (declared_type)
4891 || !CLASSTYPE_TEMPLATE_INSTANTIATION (declared_type))
4892 /* For a non-template class, use the name location. */
4893 loc = location_of (declared_type);
4894 else
4895 /* For a template class (an explicit instantiation), use the
4896 current location. */
4897 loc = input_location;
4898
4899 if (explicit_type_instantiation_p)
4900 /* [dcl.attr.grammar]/4:
4901
4902 No attribute-specifier-seq shall appertain to an explicit
4903 instantiation. */
4904 {
4905 if (warning_at (loc, OPT_Wattributes,
4906 "attribute ignored in explicit instantiation %q#T",
4907 declared_type))
4908 inform (loc,
4909 "no attribute can be applied to "
4910 "an explicit instantiation");
4911 }
4912 else
4913 warn_misplaced_attr_for_class_type (loc, declared_type);
4914 }
4915
4916 return declared_type;
4917 }
4918
4919 /* Called when a declaration is seen that contains no names to declare.
4920 If its type is a reference to a structure, union or enum inherited
4921 from a containing scope, shadow that tag name for the current scope
4922 with a forward reference.
4923 If its type defines a new named structure or union
4924 or defines an enum, it is valid but we need not do anything here.
4925 Otherwise, it is an error.
4926
4927 C++: may have to grok the declspecs to learn about static,
4928 complain for anonymous unions.
4929
4930 Returns the TYPE declared -- or NULL_TREE if none. */
4931
4932 tree
shadow_tag(cp_decl_specifier_seq * declspecs)4933 shadow_tag (cp_decl_specifier_seq *declspecs)
4934 {
4935 tree t = check_tag_decl (declspecs,
4936 /*explicit_type_instantiation_p=*/false);
4937
4938 if (!t)
4939 return NULL_TREE;
4940
4941 if (maybe_process_partial_specialization (t) == error_mark_node)
4942 return NULL_TREE;
4943
4944 /* This is where the variables in an anonymous union are
4945 declared. An anonymous union declaration looks like:
4946 union { ... } ;
4947 because there is no declarator after the union, the parser
4948 sends that declaration here. */
4949 if (ANON_AGGR_TYPE_P (t))
4950 {
4951 fixup_anonymous_aggr (t);
4952
4953 if (TYPE_FIELDS (t))
4954 {
4955 tree decl = grokdeclarator (/*declarator=*/NULL,
4956 declspecs, NORMAL, 0, NULL);
4957 finish_anon_union (decl);
4958 }
4959 }
4960
4961 return t;
4962 }
4963
4964 /* Decode a "typename", such as "int **", returning a ..._TYPE node. */
4965
4966 tree
groktypename(cp_decl_specifier_seq * type_specifiers,const cp_declarator * declarator,bool is_template_arg)4967 groktypename (cp_decl_specifier_seq *type_specifiers,
4968 const cp_declarator *declarator,
4969 bool is_template_arg)
4970 {
4971 tree attrs;
4972 tree type;
4973 enum decl_context context
4974 = is_template_arg ? TEMPLATE_TYPE_ARG : TYPENAME;
4975 attrs = type_specifiers->attributes;
4976 type_specifiers->attributes = NULL_TREE;
4977 type = grokdeclarator (declarator, type_specifiers, context, 0, &attrs);
4978 if (attrs && type != error_mark_node)
4979 {
4980 if (CLASS_TYPE_P (type))
4981 warning (OPT_Wattributes, "ignoring attributes applied to class type %qT "
4982 "outside of definition", type);
4983 else if (MAYBE_CLASS_TYPE_P (type))
4984 /* A template type parameter or other dependent type. */
4985 warning (OPT_Wattributes, "ignoring attributes applied to dependent "
4986 "type %qT without an associated declaration", type);
4987 else
4988 cplus_decl_attributes (&type, attrs, 0);
4989 }
4990 return type;
4991 }
4992
4993 /* Process a DECLARATOR for a function-scope variable declaration,
4994 namespace-scope variable declaration, or function declaration.
4995 (Function definitions go through start_function; class member
4996 declarations appearing in the body of the class go through
4997 grokfield.) The DECL corresponding to the DECLARATOR is returned.
4998 If an error occurs, the error_mark_node is returned instead.
4999
5000 DECLSPECS are the decl-specifiers for the declaration. INITIALIZED is
5001 SD_INITIALIZED if an explicit initializer is present, or SD_DEFAULTED
5002 for an explicitly defaulted function, or SD_DELETED for an explicitly
5003 deleted function, but 0 (SD_UNINITIALIZED) if this is a variable
5004 implicitly initialized via a default constructor. ATTRIBUTES and
5005 PREFIX_ATTRIBUTES are GNU attributes associated with this declaration.
5006
5007 The scope represented by the context of the returned DECL is pushed
5008 (if it is not the global namespace) and is assigned to
5009 *PUSHED_SCOPE_P. The caller is then responsible for calling
5010 pop_scope on *PUSHED_SCOPE_P if it is set. */
5011
5012 tree
start_decl(const cp_declarator * declarator,cp_decl_specifier_seq * declspecs,int initialized,tree attributes,tree prefix_attributes,tree * pushed_scope_p)5013 start_decl (const cp_declarator *declarator,
5014 cp_decl_specifier_seq *declspecs,
5015 int initialized,
5016 tree attributes,
5017 tree prefix_attributes,
5018 tree *pushed_scope_p)
5019 {
5020 tree decl;
5021 tree context;
5022 bool was_public;
5023 int flags;
5024 bool alias;
5025
5026 *pushed_scope_p = NULL_TREE;
5027
5028 /* An object declared as __attribute__((deprecated)) suppresses
5029 warnings of uses of other deprecated items. */
5030 if (lookup_attribute ("deprecated", attributes))
5031 deprecated_state = DEPRECATED_SUPPRESS;
5032
5033 attributes = chainon (attributes, prefix_attributes);
5034
5035 decl = grokdeclarator (declarator, declspecs, NORMAL, initialized,
5036 &attributes);
5037
5038 deprecated_state = DEPRECATED_NORMAL;
5039
5040 if (decl == NULL_TREE || VOID_TYPE_P (decl)
5041 || decl == error_mark_node)
5042 return error_mark_node;
5043
5044 context = CP_DECL_CONTEXT (decl);
5045 if (context != global_namespace)
5046 *pushed_scope_p = push_scope (context);
5047
5048 /* Is it valid for this decl to have an initializer at all?
5049 If not, set INITIALIZED to zero, which will indirectly
5050 tell `cp_finish_decl' to ignore the initializer once it is parsed. */
5051 if (initialized
5052 && TREE_CODE (decl) == TYPE_DECL)
5053 {
5054 error ("typedef %qD is initialized (use decltype instead)", decl);
5055 return error_mark_node;
5056 }
5057
5058 if (initialized)
5059 {
5060 if (! toplevel_bindings_p ()
5061 && DECL_EXTERNAL (decl))
5062 warning (0, "declaration of %q#D has %<extern%> and is initialized",
5063 decl);
5064 DECL_EXTERNAL (decl) = 0;
5065 if (toplevel_bindings_p ())
5066 TREE_STATIC (decl) = 1;
5067 }
5068 alias = lookup_attribute ("alias", DECL_ATTRIBUTES (decl)) != 0;
5069
5070 if (alias && TREE_CODE (decl) == FUNCTION_DECL)
5071 record_key_method_defined (decl);
5072
5073 /* If this is a typedef that names the class for linkage purposes
5074 (7.1.3p8), apply any attributes directly to the type. */
5075 if (TREE_CODE (decl) == TYPE_DECL
5076 && OVERLOAD_TYPE_P (TREE_TYPE (decl))
5077 && decl == TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (decl))))
5078 flags = ATTR_FLAG_TYPE_IN_PLACE;
5079 else
5080 flags = 0;
5081
5082 /* Set attributes here so if duplicate decl, will have proper attributes. */
5083 cplus_decl_attributes (&decl, attributes, flags);
5084
5085 /* Dllimported symbols cannot be defined. Static data members (which
5086 can be initialized in-class and dllimported) go through grokfield,
5087 not here, so we don't need to exclude those decls when checking for
5088 a definition. */
5089 if (initialized && DECL_DLLIMPORT_P (decl))
5090 {
5091 error ("definition of %q#D is marked %<dllimport%>", decl);
5092 DECL_DLLIMPORT_P (decl) = 0;
5093 }
5094
5095 /* If #pragma weak was used, mark the decl weak now. */
5096 if (!processing_template_decl && !DECL_DECOMPOSITION_P (decl))
5097 maybe_apply_pragma_weak (decl);
5098
5099 if (TREE_CODE (decl) == FUNCTION_DECL
5100 && DECL_DECLARED_INLINE_P (decl)
5101 && DECL_UNINLINABLE (decl)
5102 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl)))
5103 warning_at (DECL_SOURCE_LOCATION (decl), 0,
5104 "inline function %qD given attribute noinline", decl);
5105
5106 if (TYPE_P (context) && COMPLETE_TYPE_P (complete_type (context)))
5107 {
5108 bool this_tmpl = (processing_template_decl
5109 > template_class_depth (context));
5110 if (VAR_P (decl))
5111 {
5112 tree field = lookup_field (context, DECL_NAME (decl), 0, false);
5113 if (field == NULL_TREE
5114 || !(VAR_P (field) || variable_template_p (field)))
5115 error ("%q+#D is not a static data member of %q#T", decl, context);
5116 else if (variable_template_p (field)
5117 && (DECL_LANG_SPECIFIC (decl)
5118 && DECL_TEMPLATE_SPECIALIZATION (decl)))
5119 /* OK, specialization was already checked. */;
5120 else if (variable_template_p (field) && !this_tmpl)
5121 {
5122 error_at (DECL_SOURCE_LOCATION (decl),
5123 "non-member-template declaration of %qD", decl);
5124 inform (DECL_SOURCE_LOCATION (field), "does not match "
5125 "member template declaration here");
5126 return error_mark_node;
5127 }
5128 else
5129 {
5130 if (variable_template_p (field))
5131 field = DECL_TEMPLATE_RESULT (field);
5132
5133 if (DECL_CONTEXT (field) != context)
5134 {
5135 if (!same_type_p (DECL_CONTEXT (field), context))
5136 permerror (input_location, "ISO C++ does not permit %<%T::%D%> "
5137 "to be defined as %<%T::%D%>",
5138 DECL_CONTEXT (field), DECL_NAME (decl),
5139 context, DECL_NAME (decl));
5140 DECL_CONTEXT (decl) = DECL_CONTEXT (field);
5141 }
5142 /* Static data member are tricky; an in-class initialization
5143 still doesn't provide a definition, so the in-class
5144 declaration will have DECL_EXTERNAL set, but will have an
5145 initialization. Thus, duplicate_decls won't warn
5146 about this situation, and so we check here. */
5147 if (initialized && DECL_INITIALIZED_IN_CLASS_P (field))
5148 error ("duplicate initialization of %qD", decl);
5149 field = duplicate_decls (decl, field,
5150 /*newdecl_is_friend=*/false);
5151 if (field == error_mark_node)
5152 return error_mark_node;
5153 else if (field)
5154 decl = field;
5155 }
5156 }
5157 else
5158 {
5159 tree field = check_classfn (context, decl,
5160 this_tmpl
5161 ? current_template_parms
5162 : NULL_TREE);
5163 if (field && field != error_mark_node
5164 && duplicate_decls (decl, field,
5165 /*newdecl_is_friend=*/false))
5166 decl = field;
5167 }
5168
5169 /* cp_finish_decl sets DECL_EXTERNAL if DECL_IN_AGGR_P is set. */
5170 DECL_IN_AGGR_P (decl) = 0;
5171 /* Do not mark DECL as an explicit specialization if it was not
5172 already marked as an instantiation; a declaration should
5173 never be marked as a specialization unless we know what
5174 template is being specialized. */
5175 if (DECL_LANG_SPECIFIC (decl) && DECL_USE_TEMPLATE (decl))
5176 {
5177 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
5178 if (TREE_CODE (decl) == FUNCTION_DECL)
5179 DECL_COMDAT (decl) = (TREE_PUBLIC (decl)
5180 && DECL_DECLARED_INLINE_P (decl));
5181 else
5182 DECL_COMDAT (decl) = false;
5183
5184 /* [temp.expl.spec] An explicit specialization of a static data
5185 member of a template is a definition if the declaration
5186 includes an initializer; otherwise, it is a declaration.
5187
5188 We check for processing_specialization so this only applies
5189 to the new specialization syntax. */
5190 if (!initialized && processing_specialization)
5191 DECL_EXTERNAL (decl) = 1;
5192 }
5193
5194 if (DECL_EXTERNAL (decl) && ! DECL_TEMPLATE_SPECIALIZATION (decl)
5195 /* Aliases are definitions. */
5196 && !alias)
5197 permerror (input_location, "declaration of %q#D outside of class is not definition",
5198 decl);
5199 }
5200
5201 was_public = TREE_PUBLIC (decl);
5202
5203 /* Enter this declaration into the symbol table. Don't push the plain
5204 VAR_DECL for a variable template. */
5205 if (!template_parm_scope_p ()
5206 || !VAR_P (decl))
5207 decl = maybe_push_decl (decl);
5208
5209 if (processing_template_decl)
5210 decl = push_template_decl (decl);
5211 if (decl == error_mark_node)
5212 return error_mark_node;
5213
5214 if (VAR_P (decl)
5215 && DECL_NAMESPACE_SCOPE_P (decl) && !TREE_PUBLIC (decl) && !was_public
5216 && !DECL_THIS_STATIC (decl) && !DECL_ARTIFICIAL (decl))
5217 {
5218 /* This is a const variable with implicit 'static'. Set
5219 DECL_THIS_STATIC so we can tell it from variables that are
5220 !TREE_PUBLIC because of the anonymous namespace. */
5221 gcc_assert (CP_TYPE_CONST_P (TREE_TYPE (decl)) || errorcount);
5222 DECL_THIS_STATIC (decl) = 1;
5223 }
5224
5225 if (current_function_decl && VAR_P (decl)
5226 && DECL_DECLARED_CONSTEXPR_P (current_function_decl))
5227 {
5228 bool ok = false;
5229 if (CP_DECL_THREAD_LOCAL_P (decl))
5230 error ("%qD declared %<thread_local%> in %<constexpr%> function",
5231 decl);
5232 else if (TREE_STATIC (decl))
5233 error ("%qD declared %<static%> in %<constexpr%> function", decl);
5234 else
5235 ok = true;
5236 if (!ok)
5237 cp_function_chain->invalid_constexpr = true;
5238 }
5239
5240 if (!processing_template_decl && VAR_P (decl))
5241 start_decl_1 (decl, initialized);
5242
5243 return decl;
5244 }
5245
5246 /* Process the declaration of a variable DECL. INITIALIZED is true
5247 iff DECL is explicitly initialized. (INITIALIZED is false if the
5248 variable is initialized via an implicitly-called constructor.)
5249 This function must be called for ordinary variables (including, for
5250 example, implicit instantiations of templates), but must not be
5251 called for template declarations. */
5252
5253 void
start_decl_1(tree decl,bool initialized)5254 start_decl_1 (tree decl, bool initialized)
5255 {
5256 tree type;
5257 bool complete_p;
5258 bool aggregate_definition_p;
5259
5260 gcc_assert (!processing_template_decl);
5261
5262 if (error_operand_p (decl))
5263 return;
5264
5265 gcc_assert (VAR_P (decl));
5266
5267 type = TREE_TYPE (decl);
5268 complete_p = COMPLETE_TYPE_P (type);
5269 aggregate_definition_p = MAYBE_CLASS_TYPE_P (type) && !DECL_EXTERNAL (decl);
5270
5271 /* If an explicit initializer is present, or if this is a definition
5272 of an aggregate, then we need a complete type at this point.
5273 (Scalars are always complete types, so there is nothing to
5274 check.) This code just sets COMPLETE_P; errors (if necessary)
5275 are issued below. */
5276 if ((initialized || aggregate_definition_p)
5277 && !complete_p
5278 && COMPLETE_TYPE_P (complete_type (type)))
5279 {
5280 complete_p = true;
5281 /* We will not yet have set TREE_READONLY on DECL if the type
5282 was "const", but incomplete, before this point. But, now, we
5283 have a complete type, so we can try again. */
5284 cp_apply_type_quals_to_decl (cp_type_quals (type), decl);
5285 }
5286
5287 if (initialized)
5288 /* Is it valid for this decl to have an initializer at all? */
5289 {
5290 /* Don't allow initializations for incomplete types except for
5291 arrays which might be completed by the initialization. */
5292 if (complete_p)
5293 ; /* A complete type is ok. */
5294 else if (type_uses_auto (type))
5295 ; /* An auto type is ok. */
5296 else if (TREE_CODE (type) != ARRAY_TYPE)
5297 {
5298 error ("variable %q#D has initializer but incomplete type", decl);
5299 type = TREE_TYPE (decl) = error_mark_node;
5300 }
5301 else if (!COMPLETE_TYPE_P (complete_type (TREE_TYPE (type))))
5302 {
5303 if (DECL_LANG_SPECIFIC (decl) && DECL_TEMPLATE_INFO (decl))
5304 error ("elements of array %q#D have incomplete type", decl);
5305 /* else we already gave an error in start_decl. */
5306 }
5307 }
5308 else if (aggregate_definition_p && !complete_p)
5309 {
5310 if (type_uses_auto (type))
5311 gcc_assert (CLASS_PLACEHOLDER_TEMPLATE (type));
5312 else
5313 {
5314 error ("aggregate %q#D has incomplete type and cannot be defined",
5315 decl);
5316 /* Change the type so that assemble_variable will give
5317 DECL an rtl we can live with: (mem (const_int 0)). */
5318 type = TREE_TYPE (decl) = error_mark_node;
5319 }
5320 }
5321
5322 /* Create a new scope to hold this declaration if necessary.
5323 Whether or not a new scope is necessary cannot be determined
5324 until after the type has been completed; if the type is a
5325 specialization of a class template it is not until after
5326 instantiation has occurred that TYPE_HAS_NONTRIVIAL_DESTRUCTOR
5327 will be set correctly. */
5328 maybe_push_cleanup_level (type);
5329 }
5330
5331 /* Handle initialization of references. DECL, TYPE, and INIT have the
5332 same meaning as in cp_finish_decl. *CLEANUP must be NULL on entry,
5333 but will be set to a new CLEANUP_STMT if a temporary is created
5334 that must be destroyed subsequently.
5335
5336 Returns an initializer expression to use to initialize DECL, or
5337 NULL if the initialization can be performed statically.
5338
5339 Quotes on semantics can be found in ARM 8.4.3. */
5340
5341 static tree
grok_reference_init(tree decl,tree type,tree init,int flags)5342 grok_reference_init (tree decl, tree type, tree init, int flags)
5343 {
5344 if (init == NULL_TREE)
5345 {
5346 if ((DECL_LANG_SPECIFIC (decl) == 0
5347 || DECL_IN_AGGR_P (decl) == 0)
5348 && ! DECL_THIS_EXTERN (decl))
5349 error ("%qD declared as reference but not initialized", decl);
5350 return NULL_TREE;
5351 }
5352
5353 if (TREE_CODE (init) == TREE_LIST)
5354 init = build_x_compound_expr_from_list (init, ELK_INIT,
5355 tf_warning_or_error);
5356
5357 tree ttype = TREE_TYPE (type);
5358 if (TREE_CODE (ttype) != ARRAY_TYPE
5359 && TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE)
5360 /* Note: default conversion is only called in very special cases. */
5361 init = decay_conversion (init, tf_warning_or_error);
5362
5363 /* check_initializer handles this for non-reference variables, but for
5364 references we need to do it here or the initializer will get the
5365 incomplete array type and confuse later calls to
5366 cp_complete_array_type. */
5367 if (TREE_CODE (ttype) == ARRAY_TYPE
5368 && TYPE_DOMAIN (ttype) == NULL_TREE
5369 && (BRACE_ENCLOSED_INITIALIZER_P (init)
5370 || TREE_CODE (init) == STRING_CST))
5371 {
5372 cp_complete_array_type (&ttype, init, false);
5373 if (ttype != TREE_TYPE (type))
5374 type = cp_build_reference_type (ttype, TYPE_REF_IS_RVALUE (type));
5375 }
5376
5377 /* Convert INIT to the reference type TYPE. This may involve the
5378 creation of a temporary, whose lifetime must be the same as that
5379 of the reference. If so, a DECL_EXPR for the temporary will be
5380 added just after the DECL_EXPR for DECL. That's why we don't set
5381 DECL_INITIAL for local references (instead assigning to them
5382 explicitly); we need to allow the temporary to be initialized
5383 first. */
5384 return initialize_reference (type, init, flags,
5385 tf_warning_or_error);
5386 }
5387
5388 /* Designated initializers in arrays are not supported in GNU C++.
5389 The parser cannot detect this error since it does not know whether
5390 a given brace-enclosed initializer is for a class type or for an
5391 array. This function checks that CE does not use a designated
5392 initializer. If it does, an error is issued. Returns true if CE
5393 is valid, i.e., does not have a designated initializer. */
5394
5395 bool
check_array_designated_initializer(constructor_elt * ce,unsigned HOST_WIDE_INT index)5396 check_array_designated_initializer (constructor_elt *ce,
5397 unsigned HOST_WIDE_INT index)
5398 {
5399 /* Designated initializers for array elements are not supported. */
5400 if (ce->index)
5401 {
5402 /* The parser only allows identifiers as designated
5403 initializers. */
5404 if (ce->index == error_mark_node)
5405 {
5406 error ("name used in a GNU-style designated "
5407 "initializer for an array");
5408 return false;
5409 }
5410 else if (identifier_p (ce->index))
5411 {
5412 error ("name %qD used in a GNU-style designated "
5413 "initializer for an array", ce->index);
5414 return false;
5415 }
5416
5417 tree ce_index = build_expr_type_conversion (WANT_INT | WANT_ENUM,
5418 ce->index, true);
5419 if (ce_index
5420 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (ce_index))
5421 && (TREE_CODE (ce_index = fold_non_dependent_expr (ce_index))
5422 == INTEGER_CST))
5423 {
5424 /* A C99 designator is OK if it matches the current index. */
5425 if (wi::to_wide (ce_index) == index)
5426 {
5427 ce->index = ce_index;
5428 return true;
5429 }
5430 else
5431 sorry ("non-trivial designated initializers not supported");
5432 }
5433 else
5434 error ("C99 designator %qE is not an integral constant-expression",
5435 ce->index);
5436
5437 return false;
5438 }
5439
5440 return true;
5441 }
5442
5443 /* When parsing `int a[] = {1, 2};' we don't know the size of the
5444 array until we finish parsing the initializer. If that's the
5445 situation we're in, update DECL accordingly. */
5446
5447 static void
maybe_deduce_size_from_array_init(tree decl,tree init)5448 maybe_deduce_size_from_array_init (tree decl, tree init)
5449 {
5450 tree type = TREE_TYPE (decl);
5451
5452 if (TREE_CODE (type) == ARRAY_TYPE
5453 && TYPE_DOMAIN (type) == NULL_TREE
5454 && TREE_CODE (decl) != TYPE_DECL)
5455 {
5456 /* do_default is really a C-ism to deal with tentative definitions.
5457 But let's leave it here to ease the eventual merge. */
5458 int do_default = !DECL_EXTERNAL (decl);
5459 tree initializer = init ? init : DECL_INITIAL (decl);
5460 int failure = 0;
5461
5462 /* Check that there are no designated initializers in INIT, as
5463 those are not supported in GNU C++, and as the middle-end
5464 will crash if presented with a non-numeric designated
5465 initializer. */
5466 if (initializer && BRACE_ENCLOSED_INITIALIZER_P (initializer))
5467 {
5468 vec<constructor_elt, va_gc> *v = CONSTRUCTOR_ELTS (initializer);
5469 constructor_elt *ce;
5470 HOST_WIDE_INT i;
5471 FOR_EACH_VEC_SAFE_ELT (v, i, ce)
5472 {
5473 if (instantiation_dependent_expression_p (ce->index))
5474 return;
5475 if (!check_array_designated_initializer (ce, i))
5476 failure = 1;
5477 }
5478 }
5479
5480 if (failure)
5481 TREE_TYPE (decl) = error_mark_node;
5482 else
5483 {
5484 failure = cp_complete_array_type (&TREE_TYPE (decl), initializer,
5485 do_default);
5486 if (failure == 1)
5487 {
5488 error_at (EXPR_LOC_OR_LOC (initializer,
5489 DECL_SOURCE_LOCATION (decl)),
5490 "initializer fails to determine size of %qD", decl);
5491 }
5492 else if (failure == 2)
5493 {
5494 if (do_default)
5495 {
5496 error_at (DECL_SOURCE_LOCATION (decl),
5497 "array size missing in %qD", decl);
5498 }
5499 /* If a `static' var's size isn't known, make it extern as
5500 well as static, so it does not get allocated. If it's not
5501 `static', then don't mark it extern; finish_incomplete_decl
5502 will give it a default size and it will get allocated. */
5503 else if (!pedantic && TREE_STATIC (decl) && !TREE_PUBLIC (decl))
5504 DECL_EXTERNAL (decl) = 1;
5505 }
5506 else if (failure == 3)
5507 {
5508 error_at (DECL_SOURCE_LOCATION (decl),
5509 "zero-size array %qD", decl);
5510 }
5511 }
5512
5513 cp_apply_type_quals_to_decl (cp_type_quals (TREE_TYPE (decl)), decl);
5514
5515 relayout_decl (decl);
5516 }
5517 }
5518
5519 /* Set DECL_SIZE, DECL_ALIGN, etc. for DECL (a VAR_DECL), and issue
5520 any appropriate error messages regarding the layout. */
5521
5522 static void
layout_var_decl(tree decl)5523 layout_var_decl (tree decl)
5524 {
5525 tree type;
5526
5527 type = TREE_TYPE (decl);
5528 if (type == error_mark_node)
5529 return;
5530
5531 /* If we haven't already laid out this declaration, do so now.
5532 Note that we must not call complete type for an external object
5533 because it's type might involve templates that we are not
5534 supposed to instantiate yet. (And it's perfectly valid to say
5535 `extern X x' for some incomplete type `X'.) */
5536 if (!DECL_EXTERNAL (decl))
5537 complete_type (type);
5538 if (!DECL_SIZE (decl)
5539 && TREE_TYPE (decl) != error_mark_node
5540 && complete_or_array_type_p (type))
5541 layout_decl (decl, 0);
5542
5543 if (!DECL_EXTERNAL (decl) && DECL_SIZE (decl) == NULL_TREE)
5544 {
5545 /* An automatic variable with an incomplete type: that is an error.
5546 Don't talk about array types here, since we took care of that
5547 message in grokdeclarator. */
5548 error_at (DECL_SOURCE_LOCATION (decl),
5549 "storage size of %qD isn%'t known", decl);
5550 TREE_TYPE (decl) = error_mark_node;
5551 }
5552 #if 0
5553 /* Keep this code around in case we later want to control debug info
5554 based on whether a type is "used". (jason 1999-11-11) */
5555
5556 else if (!DECL_EXTERNAL (decl) && MAYBE_CLASS_TYPE_P (ttype))
5557 /* Let debugger know it should output info for this type. */
5558 note_debug_info_needed (ttype);
5559
5560 if (TREE_STATIC (decl) && DECL_CLASS_SCOPE_P (decl))
5561 note_debug_info_needed (DECL_CONTEXT (decl));
5562 #endif
5563
5564 if ((DECL_EXTERNAL (decl) || TREE_STATIC (decl))
5565 && DECL_SIZE (decl) != NULL_TREE
5566 && ! TREE_CONSTANT (DECL_SIZE (decl)))
5567 {
5568 if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST)
5569 constant_expression_warning (DECL_SIZE (decl));
5570 else
5571 {
5572 error_at (DECL_SOURCE_LOCATION (decl),
5573 "storage size of %qD isn%'t constant", decl);
5574 TREE_TYPE (decl) = error_mark_node;
5575 }
5576 }
5577 }
5578
5579 /* If a local static variable is declared in an inline function, or if
5580 we have a weak definition, we must endeavor to create only one
5581 instance of the variable at link-time. */
5582
5583 void
maybe_commonize_var(tree decl)5584 maybe_commonize_var (tree decl)
5585 {
5586 /* Static data in a function with comdat linkage also has comdat
5587 linkage. */
5588 if ((TREE_STATIC (decl)
5589 /* Don't mess with __FUNCTION__. */
5590 && ! DECL_ARTIFICIAL (decl)
5591 && DECL_FUNCTION_SCOPE_P (decl)
5592 && vague_linkage_p (DECL_CONTEXT (decl)))
5593 || (TREE_PUBLIC (decl) && DECL_INLINE_VAR_P (decl)))
5594 {
5595 if (flag_weak)
5596 {
5597 /* With weak symbols, we simply make the variable COMDAT;
5598 that will cause copies in multiple translations units to
5599 be merged. */
5600 comdat_linkage (decl);
5601 }
5602 else
5603 {
5604 if (DECL_INITIAL (decl) == NULL_TREE
5605 || DECL_INITIAL (decl) == error_mark_node)
5606 {
5607 /* Without weak symbols, we can use COMMON to merge
5608 uninitialized variables. */
5609 TREE_PUBLIC (decl) = 1;
5610 DECL_COMMON (decl) = 1;
5611 }
5612 else
5613 {
5614 /* While for initialized variables, we must use internal
5615 linkage -- which means that multiple copies will not
5616 be merged. */
5617 TREE_PUBLIC (decl) = 0;
5618 DECL_COMMON (decl) = 0;
5619 const char *msg;
5620 if (DECL_INLINE_VAR_P (decl))
5621 msg = G_("sorry: semantics of inline variable "
5622 "%q#D are wrong (you%'ll wind up with "
5623 "multiple copies)");
5624 else
5625 msg = G_("sorry: semantics of inline function "
5626 "static data %q#D are wrong (you%'ll wind "
5627 "up with multiple copies)");
5628 if (warning_at (DECL_SOURCE_LOCATION (decl), 0,
5629 msg, decl))
5630 inform (DECL_SOURCE_LOCATION (decl),
5631 "you can work around this by removing the initializer");
5632 }
5633 }
5634 }
5635 }
5636
5637 /* Issue an error message if DECL is an uninitialized const variable.
5638 CONSTEXPR_CONTEXT_P is true when the function is called in a constexpr
5639 context from potential_constant_expression. Returns true if all is well,
5640 false otherwise. */
5641
5642 bool
check_for_uninitialized_const_var(tree decl,bool constexpr_context_p,tsubst_flags_t complain)5643 check_for_uninitialized_const_var (tree decl, bool constexpr_context_p,
5644 tsubst_flags_t complain)
5645 {
5646 tree type = strip_array_types (TREE_TYPE (decl));
5647
5648 /* ``Unless explicitly declared extern, a const object does not have
5649 external linkage and must be initialized. ($8.4; $12.1)'' ARM
5650 7.1.6 */
5651 if (VAR_P (decl)
5652 && TREE_CODE (type) != REFERENCE_TYPE
5653 && (constexpr_context_p
5654 || CP_TYPE_CONST_P (type) || var_in_constexpr_fn (decl))
5655 && !DECL_NONTRIVIALLY_INITIALIZED_P (decl))
5656 {
5657 tree field = default_init_uninitialized_part (type);
5658 if (!field)
5659 return true;
5660
5661 if (!constexpr_context_p)
5662 {
5663 if (CP_TYPE_CONST_P (type))
5664 {
5665 if (complain & tf_error)
5666 permerror (DECL_SOURCE_LOCATION (decl),
5667 "uninitialized const %qD", decl);
5668 }
5669 else
5670 {
5671 if (!is_instantiation_of_constexpr (current_function_decl)
5672 && (complain & tf_error))
5673 error_at (DECL_SOURCE_LOCATION (decl),
5674 "uninitialized variable %qD in %<constexpr%> "
5675 "function", decl);
5676 cp_function_chain->invalid_constexpr = true;
5677 }
5678 }
5679 else if (complain & tf_error)
5680 error_at (DECL_SOURCE_LOCATION (decl),
5681 "uninitialized variable %qD in %<constexpr%> context",
5682 decl);
5683
5684 if (CLASS_TYPE_P (type) && (complain & tf_error))
5685 {
5686 tree defaulted_ctor;
5687
5688 inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (type)),
5689 "%q#T has no user-provided default constructor", type);
5690 defaulted_ctor = in_class_defaulted_default_constructor (type);
5691 if (defaulted_ctor)
5692 inform (DECL_SOURCE_LOCATION (defaulted_ctor),
5693 "constructor is not user-provided because it is "
5694 "explicitly defaulted in the class body");
5695 inform (DECL_SOURCE_LOCATION (field),
5696 "and the implicitly-defined constructor does not "
5697 "initialize %q#D", field);
5698 }
5699
5700 return false;
5701 }
5702
5703 return true;
5704 }
5705
5706 /* Structure holding the current initializer being processed by reshape_init.
5707 CUR is a pointer to the current element being processed, END is a pointer
5708 after the last element present in the initializer. */
5709 struct reshape_iter
5710 {
5711 constructor_elt *cur;
5712 constructor_elt *end;
5713 };
5714
5715 static tree reshape_init_r (tree, reshape_iter *, bool, tsubst_flags_t);
5716
5717 /* FIELD is a FIELD_DECL or NULL. In the former case, the value
5718 returned is the next FIELD_DECL (possibly FIELD itself) that can be
5719 initialized. If there are no more such fields, the return value
5720 will be NULL. */
5721
5722 tree
next_initializable_field(tree field)5723 next_initializable_field (tree field)
5724 {
5725 while (field
5726 && (TREE_CODE (field) != FIELD_DECL
5727 || DECL_UNNAMED_BIT_FIELD (field)
5728 || (DECL_ARTIFICIAL (field)
5729 && !(cxx_dialect >= cxx17 && DECL_FIELD_IS_BASE (field)))))
5730 field = DECL_CHAIN (field);
5731
5732 return field;
5733 }
5734
5735 /* Return true for [dcl.init.list] direct-list-initialization from
5736 single element of enumeration with a fixed underlying type. */
5737
5738 bool
is_direct_enum_init(tree type,tree init)5739 is_direct_enum_init (tree type, tree init)
5740 {
5741 if (cxx_dialect >= cxx17
5742 && TREE_CODE (type) == ENUMERAL_TYPE
5743 && ENUM_FIXED_UNDERLYING_TYPE_P (type)
5744 && TREE_CODE (init) == CONSTRUCTOR
5745 && CONSTRUCTOR_IS_DIRECT_INIT (init)
5746 && CONSTRUCTOR_NELTS (init) == 1)
5747 return true;
5748 return false;
5749 }
5750
5751 /* Subroutine of reshape_init_array and reshape_init_vector, which does
5752 the actual work. ELT_TYPE is the element type of the array. MAX_INDEX is an
5753 INTEGER_CST representing the size of the array minus one (the maximum index),
5754 or NULL_TREE if the array was declared without specifying the size. D is
5755 the iterator within the constructor. */
5756
5757 static tree
reshape_init_array_1(tree elt_type,tree max_index,reshape_iter * d,tsubst_flags_t complain)5758 reshape_init_array_1 (tree elt_type, tree max_index, reshape_iter *d,
5759 tsubst_flags_t complain)
5760 {
5761 tree new_init;
5762 bool sized_array_p = (max_index && TREE_CONSTANT (max_index));
5763 unsigned HOST_WIDE_INT max_index_cst = 0;
5764 unsigned HOST_WIDE_INT index;
5765
5766 /* The initializer for an array is always a CONSTRUCTOR. */
5767 new_init = build_constructor (init_list_type_node, NULL);
5768
5769 if (sized_array_p)
5770 {
5771 /* Minus 1 is used for zero sized arrays. */
5772 if (integer_all_onesp (max_index))
5773 return new_init;
5774
5775 if (tree_fits_uhwi_p (max_index))
5776 max_index_cst = tree_to_uhwi (max_index);
5777 /* sizetype is sign extended, not zero extended. */
5778 else
5779 max_index_cst = tree_to_uhwi (fold_convert (size_type_node, max_index));
5780 }
5781
5782 /* Loop until there are no more initializers. */
5783 for (index = 0;
5784 d->cur != d->end && (!sized_array_p || index <= max_index_cst);
5785 ++index)
5786 {
5787 tree elt_init;
5788 constructor_elt *old_cur = d->cur;
5789
5790 check_array_designated_initializer (d->cur, index);
5791 elt_init = reshape_init_r (elt_type, d, /*first_initializer_p=*/false,
5792 complain);
5793 if (elt_init == error_mark_node)
5794 return error_mark_node;
5795 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_init),
5796 size_int (index), elt_init);
5797 if (!TREE_CONSTANT (elt_init))
5798 TREE_CONSTANT (new_init) = false;
5799
5800 /* This can happen with an invalid initializer (c++/54501). */
5801 if (d->cur == old_cur && !sized_array_p)
5802 break;
5803 }
5804
5805 return new_init;
5806 }
5807
5808 /* Subroutine of reshape_init_r, processes the initializers for arrays.
5809 Parameters are the same of reshape_init_r. */
5810
5811 static tree
reshape_init_array(tree type,reshape_iter * d,tsubst_flags_t complain)5812 reshape_init_array (tree type, reshape_iter *d, tsubst_flags_t complain)
5813 {
5814 tree max_index = NULL_TREE;
5815
5816 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
5817
5818 if (TYPE_DOMAIN (type))
5819 max_index = array_type_nelts (type);
5820
5821 return reshape_init_array_1 (TREE_TYPE (type), max_index, d, complain);
5822 }
5823
5824 /* Subroutine of reshape_init_r, processes the initializers for vectors.
5825 Parameters are the same of reshape_init_r. */
5826
5827 static tree
reshape_init_vector(tree type,reshape_iter * d,tsubst_flags_t complain)5828 reshape_init_vector (tree type, reshape_iter *d, tsubst_flags_t complain)
5829 {
5830 tree max_index = NULL_TREE;
5831
5832 gcc_assert (VECTOR_TYPE_P (type));
5833
5834 if (COMPOUND_LITERAL_P (d->cur->value))
5835 {
5836 tree value = d->cur->value;
5837 if (!same_type_p (TREE_TYPE (value), type))
5838 {
5839 if (complain & tf_error)
5840 error ("invalid type %qT as initializer for a vector of type %qT",
5841 TREE_TYPE (d->cur->value), type);
5842 value = error_mark_node;
5843 }
5844 ++d->cur;
5845 return value;
5846 }
5847
5848 /* For a vector, we initialize it as an array of the appropriate size. */
5849 if (VECTOR_TYPE_P (type))
5850 max_index = size_int (TYPE_VECTOR_SUBPARTS (type) - 1);
5851
5852 return reshape_init_array_1 (TREE_TYPE (type), max_index, d, complain);
5853 }
5854
5855 /* Subroutine of reshape_init_r, processes the initializers for classes
5856 or union. Parameters are the same of reshape_init_r. */
5857
5858 static tree
reshape_init_class(tree type,reshape_iter * d,bool first_initializer_p,tsubst_flags_t complain)5859 reshape_init_class (tree type, reshape_iter *d, bool first_initializer_p,
5860 tsubst_flags_t complain)
5861 {
5862 tree field;
5863 tree new_init;
5864
5865 gcc_assert (CLASS_TYPE_P (type));
5866
5867 /* The initializer for a class is always a CONSTRUCTOR. */
5868 new_init = build_constructor (init_list_type_node, NULL);
5869 field = next_initializable_field (TYPE_FIELDS (type));
5870
5871 if (!field)
5872 {
5873 /* [dcl.init.aggr]
5874
5875 An initializer for an aggregate member that is an
5876 empty class shall have the form of an empty
5877 initializer-list {}. */
5878 if (!first_initializer_p)
5879 {
5880 if (complain & tf_error)
5881 error ("initializer for %qT must be brace-enclosed", type);
5882 return error_mark_node;
5883 }
5884 return new_init;
5885 }
5886
5887 /* Loop through the initializable fields, gathering initializers. */
5888 while (d->cur != d->end)
5889 {
5890 tree field_init;
5891 constructor_elt *old_cur = d->cur;
5892
5893 /* Handle designated initializers, as an extension. */
5894 if (d->cur->index)
5895 {
5896 if (d->cur->index == error_mark_node)
5897 return error_mark_node;
5898
5899 if (TREE_CODE (d->cur->index) == FIELD_DECL)
5900 {
5901 /* We already reshaped this. */
5902 if (field != d->cur->index)
5903 {
5904 tree id = DECL_NAME (d->cur->index);
5905 gcc_assert (id);
5906 gcc_checking_assert (d->cur->index
5907 == get_class_binding (type, id, false));
5908 field = d->cur->index;
5909 }
5910 }
5911 else if (TREE_CODE (d->cur->index) == IDENTIFIER_NODE)
5912 field = get_class_binding (type, d->cur->index, false);
5913 else
5914 {
5915 if (complain & tf_error)
5916 error ("%<[%E] =%> used in a GNU-style designated initializer"
5917 " for class %qT", d->cur->index, type);
5918 return error_mark_node;
5919 }
5920
5921 if (!field || TREE_CODE (field) != FIELD_DECL)
5922 {
5923 if (complain & tf_error)
5924 error ("%qT has no non-static data member named %qD", type,
5925 d->cur->index);
5926 return error_mark_node;
5927 }
5928 }
5929
5930 /* If we processed all the member of the class, we are done. */
5931 if (!field)
5932 break;
5933
5934 field_init = reshape_init_r (TREE_TYPE (field), d,
5935 /*first_initializer_p=*/false, complain);
5936 if (field_init == error_mark_node)
5937 return error_mark_node;
5938
5939 if (d->cur == old_cur && d->cur->index)
5940 {
5941 /* This can happen with an invalid initializer for a flexible
5942 array member (c++/54441). */
5943 if (complain & tf_error)
5944 error ("invalid initializer for %q#D", field);
5945 return error_mark_node;
5946 }
5947
5948 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_init), field, field_init);
5949
5950 /* [dcl.init.aggr]
5951
5952 When a union is initialized with a brace-enclosed
5953 initializer, the braces shall only contain an
5954 initializer for the first member of the union. */
5955 if (TREE_CODE (type) == UNION_TYPE)
5956 break;
5957
5958 field = next_initializable_field (DECL_CHAIN (field));
5959 }
5960
5961 return new_init;
5962 }
5963
5964 /* Subroutine of reshape_init_r. We're in a context where C99 initializer
5965 designators are not valid; either complain or return true to indicate
5966 that reshape_init_r should return error_mark_node. */
5967
5968 static bool
has_designator_problem(reshape_iter * d,tsubst_flags_t complain)5969 has_designator_problem (reshape_iter *d, tsubst_flags_t complain)
5970 {
5971 if (d->cur->index)
5972 {
5973 if (complain & tf_error)
5974 error ("C99 designator %qE outside aggregate initializer",
5975 d->cur->index);
5976 else
5977 return true;
5978 }
5979 return false;
5980 }
5981
5982 /* Subroutine of reshape_init, which processes a single initializer (part of
5983 a CONSTRUCTOR). TYPE is the type of the variable being initialized, D is the
5984 iterator within the CONSTRUCTOR which points to the initializer to process.
5985 FIRST_INITIALIZER_P is true if this is the first initializer of the
5986 outermost CONSTRUCTOR node. */
5987
5988 static tree
reshape_init_r(tree type,reshape_iter * d,bool first_initializer_p,tsubst_flags_t complain)5989 reshape_init_r (tree type, reshape_iter *d, bool first_initializer_p,
5990 tsubst_flags_t complain)
5991 {
5992 tree init = d->cur->value;
5993
5994 if (error_operand_p (init))
5995 return error_mark_node;
5996
5997 if (first_initializer_p && !CP_AGGREGATE_TYPE_P (type)
5998 && has_designator_problem (d, complain))
5999 return error_mark_node;
6000
6001 if (TREE_CODE (type) == COMPLEX_TYPE)
6002 {
6003 /* A complex type can be initialized from one or two initializers,
6004 but braces are not elided. */
6005 d->cur++;
6006 if (BRACE_ENCLOSED_INITIALIZER_P (init))
6007 {
6008 if (CONSTRUCTOR_NELTS (init) > 2)
6009 {
6010 if (complain & tf_error)
6011 error ("too many initializers for %qT", type);
6012 else
6013 return error_mark_node;
6014 }
6015 }
6016 else if (first_initializer_p && d->cur != d->end)
6017 {
6018 vec<constructor_elt, va_gc> *v = 0;
6019 CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, init);
6020 CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, d->cur->value);
6021 if (has_designator_problem (d, complain))
6022 return error_mark_node;
6023 d->cur++;
6024 init = build_constructor (init_list_type_node, v);
6025 }
6026 return init;
6027 }
6028
6029 /* A non-aggregate type is always initialized with a single
6030 initializer. */
6031 if (!CP_AGGREGATE_TYPE_P (type))
6032 {
6033 /* It is invalid to initialize a non-aggregate type with a
6034 brace-enclosed initializer before C++0x.
6035 We need to check for BRACE_ENCLOSED_INITIALIZER_P here because
6036 of g++.old-deja/g++.mike/p7626.C: a pointer-to-member constant is
6037 a CONSTRUCTOR (with a record type). */
6038 if (TREE_CODE (init) == CONSTRUCTOR
6039 /* Don't complain about a capture-init. */
6040 && !CONSTRUCTOR_IS_DIRECT_INIT (init)
6041 && BRACE_ENCLOSED_INITIALIZER_P (init)) /* p7626.C */
6042 {
6043 if (SCALAR_TYPE_P (type))
6044 {
6045 if (cxx_dialect < cxx11
6046 /* Isn't value-initialization. */
6047 || CONSTRUCTOR_NELTS (init) > 0)
6048 {
6049 if (complain & tf_error)
6050 error ("braces around scalar initializer for type %qT",
6051 type);
6052 init = error_mark_node;
6053 }
6054 }
6055 else
6056 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
6057 }
6058
6059 d->cur++;
6060 return init;
6061 }
6062
6063 /* "If T is a class type and the initializer list has a single element of
6064 type cv U, where U is T or a class derived from T, the object is
6065 initialized from that element." Even if T is an aggregate. */
6066 if (cxx_dialect >= cxx11 && (CLASS_TYPE_P (type) || VECTOR_TYPE_P (type))
6067 && first_initializer_p
6068 && d->end - d->cur == 1
6069 && reference_related_p (type, TREE_TYPE (init)))
6070 {
6071 d->cur++;
6072 return init;
6073 }
6074
6075 /* [dcl.init.aggr]
6076
6077 All implicit type conversions (clause _conv_) are considered when
6078 initializing the aggregate member with an initializer from an
6079 initializer-list. If the initializer can initialize a member,
6080 the member is initialized. Otherwise, if the member is itself a
6081 non-empty subaggregate, brace elision is assumed and the
6082 initializer is considered for the initialization of the first
6083 member of the subaggregate. */
6084 if (TREE_CODE (init) != CONSTRUCTOR
6085 /* But don't try this for the first initializer, since that would be
6086 looking through the outermost braces; A a2 = { a1 }; is not a
6087 valid aggregate initialization. */
6088 && !first_initializer_p
6089 && (same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (init))
6090 || can_convert_arg (type, TREE_TYPE (init), init, LOOKUP_NORMAL,
6091 complain)))
6092 {
6093 d->cur++;
6094 return init;
6095 }
6096
6097 /* [dcl.init.string]
6098
6099 A char array (whether plain char, signed char, or unsigned char)
6100 can be initialized by a string-literal (optionally enclosed in
6101 braces); a wchar_t array can be initialized by a wide
6102 string-literal (optionally enclosed in braces). */
6103 if (TREE_CODE (type) == ARRAY_TYPE
6104 && char_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (type))))
6105 {
6106 tree str_init = init;
6107
6108 /* Strip one level of braces if and only if they enclose a single
6109 element (as allowed by [dcl.init.string]). */
6110 if (!first_initializer_p
6111 && TREE_CODE (str_init) == CONSTRUCTOR
6112 && CONSTRUCTOR_NELTS (str_init) == 1)
6113 {
6114 str_init = (*CONSTRUCTOR_ELTS (str_init))[0].value;
6115 }
6116
6117 /* If it's a string literal, then it's the initializer for the array
6118 as a whole. Otherwise, continue with normal initialization for
6119 array types (one value per array element). */
6120 if (TREE_CODE (str_init) == STRING_CST)
6121 {
6122 if (has_designator_problem (d, complain))
6123 return error_mark_node;
6124 d->cur++;
6125 return str_init;
6126 }
6127 }
6128
6129 /* The following cases are about aggregates. If we are not within a full
6130 initializer already, and there is not a CONSTRUCTOR, it means that there
6131 is a missing set of braces (that is, we are processing the case for
6132 which reshape_init exists). */
6133 if (!first_initializer_p)
6134 {
6135 if (TREE_CODE (init) == CONSTRUCTOR)
6136 {
6137 tree init_type = TREE_TYPE (init);
6138 if (init_type && TYPE_PTRMEMFUNC_P (init_type))
6139 /* There is no need to call reshape_init for pointer-to-member
6140 function initializers, as they are always constructed correctly
6141 by the front end. Here we have e.g. {.__pfn=0B, .__delta=0},
6142 which is missing outermost braces. We should warn below, and
6143 one of the routines below will wrap it in additional { }. */;
6144 /* For a nested compound literal, there is no need to reshape since
6145 we called reshape_init in finish_compound_literal, before calling
6146 digest_init. */
6147 else if (COMPOUND_LITERAL_P (init)
6148 /* Similarly, a CONSTRUCTOR of the target's type is a
6149 previously digested initializer. */
6150 || same_type_ignoring_top_level_qualifiers_p (type,
6151 init_type))
6152 {
6153 ++d->cur;
6154 gcc_assert (!BRACE_ENCLOSED_INITIALIZER_P (init));
6155 return init;
6156 }
6157 else
6158 {
6159 /* Something that hasn't been reshaped yet. */
6160 ++d->cur;
6161 gcc_assert (BRACE_ENCLOSED_INITIALIZER_P (init));
6162 return reshape_init (type, init, complain);
6163 }
6164 }
6165
6166 if (complain & tf_warning)
6167 warning (OPT_Wmissing_braces,
6168 "missing braces around initializer for %qT",
6169 type);
6170 }
6171
6172 /* Dispatch to specialized routines. */
6173 if (CLASS_TYPE_P (type))
6174 return reshape_init_class (type, d, first_initializer_p, complain);
6175 else if (TREE_CODE (type) == ARRAY_TYPE)
6176 return reshape_init_array (type, d, complain);
6177 else if (VECTOR_TYPE_P (type))
6178 return reshape_init_vector (type, d, complain);
6179 else
6180 gcc_unreachable();
6181 }
6182
6183 /* Undo the brace-elision allowed by [dcl.init.aggr] in a
6184 brace-enclosed aggregate initializer.
6185
6186 INIT is the CONSTRUCTOR containing the list of initializers describing
6187 a brace-enclosed initializer for an entity of the indicated aggregate TYPE.
6188 It may not presently match the shape of the TYPE; for example:
6189
6190 struct S { int a; int b; };
6191 struct S a[] = { 1, 2, 3, 4 };
6192
6193 Here INIT will hold a vector of four elements, rather than a
6194 vector of two elements, each itself a vector of two elements. This
6195 routine transforms INIT from the former form into the latter. The
6196 revised CONSTRUCTOR node is returned. */
6197
6198 tree
reshape_init(tree type,tree init,tsubst_flags_t complain)6199 reshape_init (tree type, tree init, tsubst_flags_t complain)
6200 {
6201 vec<constructor_elt, va_gc> *v;
6202 reshape_iter d;
6203 tree new_init;
6204
6205 gcc_assert (BRACE_ENCLOSED_INITIALIZER_P (init));
6206
6207 v = CONSTRUCTOR_ELTS (init);
6208
6209 /* An empty constructor does not need reshaping, and it is always a valid
6210 initializer. */
6211 if (vec_safe_is_empty (v))
6212 return init;
6213
6214 /* Handle [dcl.init.list] direct-list-initialization from
6215 single element of enumeration with a fixed underlying type. */
6216 if (is_direct_enum_init (type, init))
6217 {
6218 tree elt = CONSTRUCTOR_ELT (init, 0)->value;
6219 type = cv_unqualified (type);
6220 if (check_narrowing (ENUM_UNDERLYING_TYPE (type), elt, complain))
6221 {
6222 warning_sentinel w (warn_useless_cast);
6223 warning_sentinel w2 (warn_ignored_qualifiers);
6224 return cp_build_c_cast (type, elt, tf_warning_or_error);
6225 }
6226 else
6227 return error_mark_node;
6228 }
6229
6230 /* Recurse on this CONSTRUCTOR. */
6231 d.cur = &(*v)[0];
6232 d.end = d.cur + v->length ();
6233
6234 new_init = reshape_init_r (type, &d, true, complain);
6235 if (new_init == error_mark_node)
6236 return error_mark_node;
6237
6238 /* Make sure all the element of the constructor were used. Otherwise,
6239 issue an error about exceeding initializers. */
6240 if (d.cur != d.end)
6241 {
6242 if (complain & tf_error)
6243 error ("too many initializers for %qT", type);
6244 return error_mark_node;
6245 }
6246
6247 if (CONSTRUCTOR_IS_DIRECT_INIT (init)
6248 && BRACE_ENCLOSED_INITIALIZER_P (new_init))
6249 CONSTRUCTOR_IS_DIRECT_INIT (new_init) = true;
6250
6251 return new_init;
6252 }
6253
6254 /* Verify array initializer. Returns true if errors have been reported. */
6255
6256 bool
check_array_initializer(tree decl,tree type,tree init)6257 check_array_initializer (tree decl, tree type, tree init)
6258 {
6259 tree element_type = TREE_TYPE (type);
6260
6261 /* The array type itself need not be complete, because the
6262 initializer may tell us how many elements are in the array.
6263 But, the elements of the array must be complete. */
6264 if (!COMPLETE_TYPE_P (complete_type (element_type)))
6265 {
6266 if (decl)
6267 error_at (DECL_SOURCE_LOCATION (decl),
6268 "elements of array %q#D have incomplete type", decl);
6269 else
6270 error ("elements of array %q#T have incomplete type", type);
6271 return true;
6272 }
6273 /* A compound literal can't have variable size. */
6274 if (init && !decl
6275 && ((COMPLETE_TYPE_P (type) && !TREE_CONSTANT (TYPE_SIZE (type)))
6276 || !TREE_CONSTANT (TYPE_SIZE (element_type))))
6277 {
6278 error ("variable-sized compound literal");
6279 return true;
6280 }
6281 return false;
6282 }
6283
6284 /* Subroutine of check_initializer; args are passed down from that function.
6285 Set stmts_are_full_exprs_p to 1 across a call to build_aggr_init. */
6286
6287 static tree
build_aggr_init_full_exprs(tree decl,tree init,int flags)6288 build_aggr_init_full_exprs (tree decl, tree init, int flags)
6289
6290 {
6291 gcc_assert (stmts_are_full_exprs_p ());
6292 return build_aggr_init (decl, init, flags, tf_warning_or_error);
6293 }
6294
6295 /* Verify INIT (the initializer for DECL), and record the
6296 initialization in DECL_INITIAL, if appropriate. CLEANUP is as for
6297 grok_reference_init.
6298
6299 If the return value is non-NULL, it is an expression that must be
6300 evaluated dynamically to initialize DECL. */
6301
6302 static tree
check_initializer(tree decl,tree init,int flags,vec<tree,va_gc> ** cleanups)6303 check_initializer (tree decl, tree init, int flags, vec<tree, va_gc> **cleanups)
6304 {
6305 tree type = TREE_TYPE (decl);
6306 tree init_code = NULL;
6307 tree core_type;
6308
6309 /* Things that are going to be initialized need to have complete
6310 type. */
6311 TREE_TYPE (decl) = type = complete_type (TREE_TYPE (decl));
6312
6313 if (DECL_HAS_VALUE_EXPR_P (decl))
6314 {
6315 /* A variable with DECL_HAS_VALUE_EXPR_P set is just a placeholder,
6316 it doesn't have storage to be initialized. */
6317 gcc_assert (init == NULL_TREE);
6318 return NULL_TREE;
6319 }
6320
6321 if (type == error_mark_node)
6322 /* We will have already complained. */
6323 return NULL_TREE;
6324
6325 if (TREE_CODE (type) == ARRAY_TYPE)
6326 {
6327 if (check_array_initializer (decl, type, init))
6328 return NULL_TREE;
6329 }
6330 else if (!COMPLETE_TYPE_P (type))
6331 {
6332 error_at (DECL_SOURCE_LOCATION (decl),
6333 "%q#D has incomplete type", decl);
6334 TREE_TYPE (decl) = error_mark_node;
6335 return NULL_TREE;
6336 }
6337 else
6338 /* There is no way to make a variable-sized class type in GNU C++. */
6339 gcc_assert (TREE_CONSTANT (TYPE_SIZE (type)));
6340
6341 if (init && BRACE_ENCLOSED_INITIALIZER_P (init))
6342 {
6343 int init_len = CONSTRUCTOR_NELTS (init);
6344 if (SCALAR_TYPE_P (type))
6345 {
6346 if (init_len == 0)
6347 {
6348 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
6349 init = build_zero_init (type, NULL_TREE, false);
6350 }
6351 else if (init_len != 1 && TREE_CODE (type) != COMPLEX_TYPE)
6352 {
6353 error_at (EXPR_LOC_OR_LOC (init, DECL_SOURCE_LOCATION (decl)),
6354 "scalar object %qD requires one element in "
6355 "initializer", decl);
6356 TREE_TYPE (decl) = error_mark_node;
6357 return NULL_TREE;
6358 }
6359 }
6360 }
6361
6362 if (TREE_CODE (decl) == CONST_DECL)
6363 {
6364 gcc_assert (TREE_CODE (type) != REFERENCE_TYPE);
6365
6366 DECL_INITIAL (decl) = init;
6367
6368 gcc_assert (init != NULL_TREE);
6369 init = NULL_TREE;
6370 }
6371 else if (!init && DECL_REALLY_EXTERN (decl))
6372 ;
6373 else if (init || type_build_ctor_call (type)
6374 || TREE_CODE (type) == REFERENCE_TYPE)
6375 {
6376 if (TREE_CODE (type) == REFERENCE_TYPE)
6377 {
6378 init = grok_reference_init (decl, type, init, flags);
6379 flags |= LOOKUP_ALREADY_DIGESTED;
6380 }
6381 else if (!init)
6382 check_for_uninitialized_const_var (decl, /*constexpr_context_p=*/false,
6383 tf_warning_or_error);
6384 /* Do not reshape constructors of vectors (they don't need to be
6385 reshaped. */
6386 else if (BRACE_ENCLOSED_INITIALIZER_P (init))
6387 {
6388 if (is_std_init_list (type))
6389 {
6390 init = perform_implicit_conversion (type, init,
6391 tf_warning_or_error);
6392 flags |= LOOKUP_ALREADY_DIGESTED;
6393 }
6394 else if (TYPE_NON_AGGREGATE_CLASS (type))
6395 {
6396 /* Don't reshape if the class has constructors. */
6397 if (cxx_dialect == cxx98)
6398 error_at (EXPR_LOC_OR_LOC (init, DECL_SOURCE_LOCATION (decl)),
6399 "in C++98 %qD must be initialized by "
6400 "constructor, not by %<{...}%>",
6401 decl);
6402 }
6403 else if (VECTOR_TYPE_P (type) && TYPE_VECTOR_OPAQUE (type))
6404 {
6405 error ("opaque vector types cannot be initialized");
6406 init = error_mark_node;
6407 }
6408 else
6409 {
6410 init = reshape_init (type, init, tf_warning_or_error);
6411 flags |= LOOKUP_NO_NARROWING;
6412 }
6413 }
6414 else if (TREE_CODE (init) == TREE_LIST
6415 && TREE_TYPE (init) != unknown_type_node
6416 && !MAYBE_CLASS_TYPE_P (type))
6417 {
6418 gcc_assert (TREE_CODE (decl) != RESULT_DECL);
6419
6420 /* We get here with code like `int a (2);' */
6421 init = build_x_compound_expr_from_list (init, ELK_INIT,
6422 tf_warning_or_error);
6423 }
6424
6425 /* If DECL has an array type without a specific bound, deduce the
6426 array size from the initializer. */
6427 maybe_deduce_size_from_array_init (decl, init);
6428 type = TREE_TYPE (decl);
6429 if (type == error_mark_node)
6430 return NULL_TREE;
6431
6432 if (((type_build_ctor_call (type) || CLASS_TYPE_P (type))
6433 && !(flags & LOOKUP_ALREADY_DIGESTED)
6434 && !(init && BRACE_ENCLOSED_INITIALIZER_P (init)
6435 && CP_AGGREGATE_TYPE_P (type)
6436 && (CLASS_TYPE_P (type)
6437 || !TYPE_NEEDS_CONSTRUCTING (type)
6438 || type_has_extended_temps (type))))
6439 || (DECL_DECOMPOSITION_P (decl) && TREE_CODE (type) == ARRAY_TYPE))
6440 {
6441 init_code = build_aggr_init_full_exprs (decl, init, flags);
6442
6443 /* A constructor call is a non-trivial initializer even if
6444 it isn't explicitly written. */
6445 if (TREE_SIDE_EFFECTS (init_code))
6446 DECL_NONTRIVIALLY_INITIALIZED_P (decl) = true;
6447
6448 /* If this is a constexpr initializer, expand_default_init will
6449 have returned an INIT_EXPR rather than a CALL_EXPR. In that
6450 case, pull the initializer back out and pass it down into
6451 store_init_value. */
6452 while (TREE_CODE (init_code) == EXPR_STMT
6453 || TREE_CODE (init_code) == CONVERT_EXPR)
6454 init_code = TREE_OPERAND (init_code, 0);
6455 if (TREE_CODE (init_code) == INIT_EXPR)
6456 {
6457 init = TREE_OPERAND (init_code, 1);
6458 init_code = NULL_TREE;
6459 /* Don't call digest_init; it's unnecessary and will complain
6460 about aggregate initialization of non-aggregate classes. */
6461 flags |= LOOKUP_ALREADY_DIGESTED;
6462 }
6463 else if (DECL_DECLARED_CONSTEXPR_P (decl))
6464 {
6465 /* Declared constexpr, but no suitable initializer; massage
6466 init appropriately so we can pass it into store_init_value
6467 for the error. */
6468 if (CLASS_TYPE_P (type)
6469 && (!init || TREE_CODE (init) == TREE_LIST))
6470 {
6471 init = build_functional_cast (type, init, tf_none);
6472 if (TREE_CODE (init) == TARGET_EXPR)
6473 TARGET_EXPR_DIRECT_INIT_P (init) = true;
6474 }
6475 init_code = NULL_TREE;
6476 }
6477 else
6478 init = NULL_TREE;
6479 }
6480
6481 if (init && TREE_CODE (init) != TREE_VEC)
6482 {
6483 /* In aggregate initialization of a variable, each element
6484 initialization is a full-expression because there is no
6485 enclosing expression. */
6486 gcc_assert (stmts_are_full_exprs_p ());
6487
6488 init_code = store_init_value (decl, init, cleanups, flags);
6489
6490 if (pedantic && TREE_CODE (type) == ARRAY_TYPE
6491 && DECL_INITIAL (decl)
6492 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
6493 && PAREN_STRING_LITERAL_P (DECL_INITIAL (decl)))
6494 warning_at (EXPR_LOC_OR_LOC (DECL_INITIAL (decl),
6495 DECL_SOURCE_LOCATION (decl)),
6496 0, "array %qD initialized by parenthesized "
6497 "string literal %qE",
6498 decl, DECL_INITIAL (decl));
6499 init = NULL;
6500 }
6501 }
6502 else
6503 {
6504 if (CLASS_TYPE_P (core_type = strip_array_types (type))
6505 && (CLASSTYPE_READONLY_FIELDS_NEED_INIT (core_type)
6506 || CLASSTYPE_REF_FIELDS_NEED_INIT (core_type)))
6507 diagnose_uninitialized_cst_or_ref_member (core_type, /*using_new=*/false,
6508 /*complain=*/true);
6509
6510 check_for_uninitialized_const_var (decl, /*constexpr_context_p=*/false,
6511 tf_warning_or_error);
6512 }
6513
6514 if (init && init != error_mark_node)
6515 init_code = build2 (INIT_EXPR, type, decl, init);
6516
6517 if (init_code)
6518 {
6519 /* We might have set these in cp_finish_decl. */
6520 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl) = false;
6521 TREE_CONSTANT (decl) = false;
6522 }
6523
6524 if (init_code
6525 && (DECL_IN_AGGR_P (decl)
6526 && DECL_INITIALIZED_IN_CLASS_P (decl)
6527 && !DECL_VAR_DECLARED_INLINE_P (decl)))
6528 {
6529 static int explained = 0;
6530
6531 if (cxx_dialect < cxx11)
6532 error ("initializer invalid for static member with constructor");
6533 else if (cxx_dialect < cxx17)
6534 error ("non-constant in-class initialization invalid for static "
6535 "member %qD", decl);
6536 else
6537 error ("non-constant in-class initialization invalid for non-inline "
6538 "static member %qD", decl);
6539 if (!explained)
6540 {
6541 inform (input_location,
6542 "(an out of class initialization is required)");
6543 explained = 1;
6544 }
6545 return NULL_TREE;
6546 }
6547
6548 return init_code;
6549 }
6550
6551 /* If DECL is not a local variable, give it RTL. */
6552
6553 static void
make_rtl_for_nonlocal_decl(tree decl,tree init,const char * asmspec)6554 make_rtl_for_nonlocal_decl (tree decl, tree init, const char* asmspec)
6555 {
6556 int toplev = toplevel_bindings_p ();
6557 int defer_p;
6558
6559 /* Set the DECL_ASSEMBLER_NAME for the object. */
6560 if (asmspec)
6561 {
6562 /* The `register' keyword, when used together with an
6563 asm-specification, indicates that the variable should be
6564 placed in a particular register. */
6565 if (VAR_P (decl) && DECL_REGISTER (decl))
6566 {
6567 set_user_assembler_name (decl, asmspec);
6568 DECL_HARD_REGISTER (decl) = 1;
6569 }
6570 else
6571 {
6572 if (TREE_CODE (decl) == FUNCTION_DECL
6573 && DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL)
6574 set_builtin_user_assembler_name (decl, asmspec);
6575 set_user_assembler_name (decl, asmspec);
6576 }
6577 }
6578
6579 /* Handle non-variables up front. */
6580 if (!VAR_P (decl))
6581 {
6582 rest_of_decl_compilation (decl, toplev, at_eof);
6583 return;
6584 }
6585
6586 /* If we see a class member here, it should be a static data
6587 member. */
6588 if (DECL_LANG_SPECIFIC (decl) && DECL_IN_AGGR_P (decl))
6589 {
6590 gcc_assert (TREE_STATIC (decl));
6591 /* An in-class declaration of a static data member should be
6592 external; it is only a declaration, and not a definition. */
6593 if (init == NULL_TREE)
6594 gcc_assert (DECL_EXTERNAL (decl)
6595 || !TREE_PUBLIC (decl)
6596 || DECL_INLINE_VAR_P (decl));
6597 }
6598
6599 /* We don't create any RTL for local variables. */
6600 if (DECL_FUNCTION_SCOPE_P (decl) && !TREE_STATIC (decl))
6601 return;
6602
6603 /* We defer emission of local statics until the corresponding
6604 DECL_EXPR is expanded. But with constexpr its function might never
6605 be expanded, so go ahead and tell cgraph about the variable now. */
6606 defer_p = ((DECL_FUNCTION_SCOPE_P (decl)
6607 && !var_in_maybe_constexpr_fn (decl))
6608 || DECL_VIRTUAL_P (decl));
6609
6610 /* Defer template instantiations. */
6611 if (DECL_LANG_SPECIFIC (decl)
6612 && DECL_IMPLICIT_INSTANTIATION (decl))
6613 defer_p = 1;
6614
6615 /* If we're not deferring, go ahead and assemble the variable. */
6616 if (!defer_p)
6617 rest_of_decl_compilation (decl, toplev, at_eof);
6618 }
6619
6620 /* walk_tree helper for wrap_temporary_cleanups, below. */
6621
6622 static tree
wrap_cleanups_r(tree * stmt_p,int * walk_subtrees,void * data)6623 wrap_cleanups_r (tree *stmt_p, int *walk_subtrees, void *data)
6624 {
6625 /* Stop at types or full-expression boundaries. */
6626 if (TYPE_P (*stmt_p)
6627 || TREE_CODE (*stmt_p) == CLEANUP_POINT_EXPR)
6628 {
6629 *walk_subtrees = 0;
6630 return NULL_TREE;
6631 }
6632
6633 if (TREE_CODE (*stmt_p) == TARGET_EXPR)
6634 {
6635 tree guard = (tree)data;
6636 tree tcleanup = TARGET_EXPR_CLEANUP (*stmt_p);
6637
6638 tcleanup = build2 (TRY_CATCH_EXPR, void_type_node, tcleanup, guard);
6639 /* Tell honor_protect_cleanup_actions to handle this as a separate
6640 cleanup. */
6641 TRY_CATCH_IS_CLEANUP (tcleanup) = 1;
6642
6643 TARGET_EXPR_CLEANUP (*stmt_p) = tcleanup;
6644 }
6645
6646 return NULL_TREE;
6647 }
6648
6649 /* We're initializing a local variable which has a cleanup GUARD. If there
6650 are any temporaries used in the initializer INIT of this variable, we
6651 need to wrap their cleanups with TRY_CATCH_EXPR (, GUARD) so that the
6652 variable will be cleaned up properly if one of them throws.
6653
6654 Unfortunately, there's no way to express this properly in terms of
6655 nesting, as the regions for the temporaries overlap the region for the
6656 variable itself; if there are two temporaries, the variable needs to be
6657 the first thing destroyed if either of them throws. However, we only
6658 want to run the variable's cleanup if it actually got constructed. So
6659 we need to guard the temporary cleanups with the variable's cleanup if
6660 they are run on the normal path, but not if they are run on the
6661 exceptional path. We implement this by telling
6662 honor_protect_cleanup_actions to strip the variable cleanup from the
6663 exceptional path. */
6664
6665 static void
wrap_temporary_cleanups(tree init,tree guard)6666 wrap_temporary_cleanups (tree init, tree guard)
6667 {
6668 cp_walk_tree_without_duplicates (&init, wrap_cleanups_r, (void *)guard);
6669 }
6670
6671 /* Generate code to initialize DECL (a local variable). */
6672
6673 static void
initialize_local_var(tree decl,tree init)6674 initialize_local_var (tree decl, tree init)
6675 {
6676 tree type = TREE_TYPE (decl);
6677 tree cleanup;
6678 int already_used;
6679
6680 gcc_assert (VAR_P (decl)
6681 || TREE_CODE (decl) == RESULT_DECL);
6682 gcc_assert (!TREE_STATIC (decl));
6683
6684 if (DECL_SIZE (decl) == NULL_TREE)
6685 {
6686 /* If we used it already as memory, it must stay in memory. */
6687 DECL_INITIAL (decl) = NULL_TREE;
6688 TREE_ADDRESSABLE (decl) = TREE_USED (decl);
6689 return;
6690 }
6691
6692 if (type == error_mark_node)
6693 return;
6694
6695 /* Compute and store the initial value. */
6696 already_used = TREE_USED (decl) || TREE_USED (type);
6697 if (TREE_USED (type))
6698 DECL_READ_P (decl) = 1;
6699
6700 /* Generate a cleanup, if necessary. */
6701 cleanup = cxx_maybe_build_cleanup (decl, tf_warning_or_error);
6702
6703 /* Perform the initialization. */
6704 if (init)
6705 {
6706 tree rinit = (TREE_CODE (init) == INIT_EXPR
6707 ? TREE_OPERAND (init, 1) : NULL_TREE);
6708 if (rinit && !TREE_SIDE_EFFECTS (rinit))
6709 {
6710 /* Stick simple initializers in DECL_INITIAL so that
6711 -Wno-init-self works (c++/34772). */
6712 gcc_assert (TREE_OPERAND (init, 0) == decl);
6713 DECL_INITIAL (decl) = rinit;
6714
6715 if (warn_init_self && TREE_CODE (type) == REFERENCE_TYPE)
6716 {
6717 STRIP_NOPS (rinit);
6718 if (rinit == decl)
6719 warning_at (DECL_SOURCE_LOCATION (decl),
6720 OPT_Winit_self,
6721 "reference %qD is initialized with itself", decl);
6722 }
6723 }
6724 else
6725 {
6726 int saved_stmts_are_full_exprs_p;
6727
6728 /* If we're only initializing a single object, guard the
6729 destructors of any temporaries used in its initializer with
6730 its destructor. This isn't right for arrays because each
6731 element initialization is a full-expression. */
6732 if (cleanup && TREE_CODE (type) != ARRAY_TYPE)
6733 wrap_temporary_cleanups (init, cleanup);
6734
6735 gcc_assert (building_stmt_list_p ());
6736 saved_stmts_are_full_exprs_p = stmts_are_full_exprs_p ();
6737 current_stmt_tree ()->stmts_are_full_exprs_p = 1;
6738 finish_expr_stmt (init);
6739 current_stmt_tree ()->stmts_are_full_exprs_p =
6740 saved_stmts_are_full_exprs_p;
6741 }
6742 }
6743
6744 /* Set this to 0 so we can tell whether an aggregate which was
6745 initialized was ever used. Don't do this if it has a
6746 destructor, so we don't complain about the 'resource
6747 allocation is initialization' idiom. Now set
6748 attribute((unused)) on types so decls of that type will be
6749 marked used. (see TREE_USED, above.) */
6750 if (TYPE_NEEDS_CONSTRUCTING (type)
6751 && ! already_used
6752 && TYPE_HAS_TRIVIAL_DESTRUCTOR (type)
6753 && DECL_NAME (decl))
6754 TREE_USED (decl) = 0;
6755 else if (already_used)
6756 TREE_USED (decl) = 1;
6757
6758 if (cleanup)
6759 finish_decl_cleanup (decl, cleanup);
6760 }
6761
6762 /* DECL is a VAR_DECL for a compiler-generated variable with static
6763 storage duration (like a virtual table) whose initializer is a
6764 compile-time constant. Initialize the variable and provide it to the
6765 back end. */
6766
6767 void
initialize_artificial_var(tree decl,vec<constructor_elt,va_gc> * v)6768 initialize_artificial_var (tree decl, vec<constructor_elt, va_gc> *v)
6769 {
6770 tree init;
6771 gcc_assert (DECL_ARTIFICIAL (decl));
6772 init = build_constructor (TREE_TYPE (decl), v);
6773 gcc_assert (TREE_CODE (init) == CONSTRUCTOR);
6774 DECL_INITIAL (decl) = init;
6775 DECL_INITIALIZED_P (decl) = 1;
6776 determine_visibility (decl);
6777 layout_var_decl (decl);
6778 maybe_commonize_var (decl);
6779 make_rtl_for_nonlocal_decl (decl, init, /*asmspec=*/NULL);
6780 }
6781
6782 /* INIT is the initializer for a variable, as represented by the
6783 parser. Returns true iff INIT is value-dependent. */
6784
6785 static bool
value_dependent_init_p(tree init)6786 value_dependent_init_p (tree init)
6787 {
6788 if (TREE_CODE (init) == TREE_LIST)
6789 /* A parenthesized initializer, e.g.: int i (3, 2); ? */
6790 return any_value_dependent_elements_p (init);
6791 else if (TREE_CODE (init) == CONSTRUCTOR)
6792 /* A brace-enclosed initializer, e.g.: int i = { 3 }; ? */
6793 {
6794 if (dependent_type_p (TREE_TYPE (init)))
6795 return true;
6796
6797 vec<constructor_elt, va_gc> *elts;
6798 size_t nelts;
6799 size_t i;
6800
6801 elts = CONSTRUCTOR_ELTS (init);
6802 nelts = vec_safe_length (elts);
6803 for (i = 0; i < nelts; ++i)
6804 if (value_dependent_init_p ((*elts)[i].value))
6805 return true;
6806 }
6807 else
6808 /* It must be a simple expression, e.g., int i = 3; */
6809 return value_dependent_expression_p (init);
6810
6811 return false;
6812 }
6813
6814 // Returns true if a DECL is VAR_DECL with the concept specifier.
6815 static inline bool
is_concept_var(tree decl)6816 is_concept_var (tree decl)
6817 {
6818 return (VAR_P (decl)
6819 // Not all variables have DECL_LANG_SPECIFIC.
6820 && DECL_LANG_SPECIFIC (decl)
6821 && DECL_DECLARED_CONCEPT_P (decl));
6822 }
6823
6824 /* A helper function to be called via walk_tree. If any label exists
6825 under *TP, it is (going to be) forced. Set has_forced_label_in_static. */
6826
6827 static tree
notice_forced_label_r(tree * tp,int * walk_subtrees,void *)6828 notice_forced_label_r (tree *tp, int *walk_subtrees, void *)
6829 {
6830 if (TYPE_P (*tp))
6831 *walk_subtrees = 0;
6832 if (TREE_CODE (*tp) == LABEL_DECL)
6833 cfun->has_forced_label_in_static = 1;
6834 return NULL_TREE;
6835 }
6836
6837 /* Finish processing of a declaration;
6838 install its line number and initial value.
6839 If the length of an array type is not known before,
6840 it must be determined now, from the initial value, or it is an error.
6841
6842 INIT is the initializer (if any) for DECL. If INIT_CONST_EXPR_P is
6843 true, then INIT is an integral constant expression.
6844
6845 FLAGS is LOOKUP_ONLYCONVERTING if the = init syntax was used, else 0
6846 if the (init) syntax was used. */
6847
6848 void
cp_finish_decl(tree decl,tree init,bool init_const_expr_p,tree asmspec_tree,int flags)6849 cp_finish_decl (tree decl, tree init, bool init_const_expr_p,
6850 tree asmspec_tree, int flags)
6851 {
6852 tree type;
6853 vec<tree, va_gc> *cleanups = NULL;
6854 const char *asmspec = NULL;
6855 int was_readonly = 0;
6856 bool var_definition_p = false;
6857 tree auto_node;
6858
6859 if (decl == error_mark_node)
6860 return;
6861 else if (! decl)
6862 {
6863 if (init)
6864 error ("assignment (not initialization) in declaration");
6865 return;
6866 }
6867
6868 gcc_assert (TREE_CODE (decl) != RESULT_DECL);
6869 /* Parameters are handled by store_parm_decls, not cp_finish_decl. */
6870 gcc_assert (TREE_CODE (decl) != PARM_DECL);
6871
6872 type = TREE_TYPE (decl);
6873 if (type == error_mark_node)
6874 return;
6875
6876 /* Warn about register storage specifiers except when in GNU global
6877 or local register variable extension. */
6878 if (VAR_P (decl) && DECL_REGISTER (decl) && asmspec_tree == NULL_TREE)
6879 {
6880 if (cxx_dialect >= cxx17)
6881 pedwarn (DECL_SOURCE_LOCATION (decl), OPT_Wregister,
6882 "ISO C++17 does not allow %<register%> storage "
6883 "class specifier");
6884 else
6885 warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wregister,
6886 "%<register%> storage class specifier used");
6887 }
6888
6889 /* If a name was specified, get the string. */
6890 if (at_namespace_scope_p ())
6891 asmspec_tree = maybe_apply_renaming_pragma (decl, asmspec_tree);
6892 if (asmspec_tree && asmspec_tree != error_mark_node)
6893 asmspec = TREE_STRING_POINTER (asmspec_tree);
6894
6895 if (current_class_type
6896 && CP_DECL_CONTEXT (decl) == current_class_type
6897 && TYPE_BEING_DEFINED (current_class_type)
6898 && !CLASSTYPE_TEMPLATE_INSTANTIATION (current_class_type)
6899 && (DECL_INITIAL (decl) || init))
6900 DECL_INITIALIZED_IN_CLASS_P (decl) = 1;
6901
6902 if (TREE_CODE (decl) != FUNCTION_DECL
6903 && (auto_node = type_uses_auto (type)))
6904 {
6905 tree d_init;
6906 if (init == NULL_TREE)
6907 {
6908 if (DECL_LANG_SPECIFIC (decl)
6909 && DECL_TEMPLATE_INSTANTIATION (decl)
6910 && !DECL_TEMPLATE_INSTANTIATED (decl))
6911 {
6912 /* init is null because we're deferring instantiating the
6913 initializer until we need it. Well, we need it now. */
6914 instantiate_decl (decl, /*defer_ok*/true, /*expl*/false);
6915 return;
6916 }
6917
6918 gcc_assert (CLASS_PLACEHOLDER_TEMPLATE (auto_node));
6919 }
6920 d_init = init;
6921 if (d_init)
6922 {
6923 if (TREE_CODE (d_init) == TREE_LIST
6924 && !CLASS_PLACEHOLDER_TEMPLATE (auto_node))
6925 d_init = build_x_compound_expr_from_list (d_init, ELK_INIT,
6926 tf_warning_or_error);
6927 d_init = resolve_nondeduced_context (d_init, tf_warning_or_error);
6928 }
6929 enum auto_deduction_context adc = adc_variable_type;
6930 if (VAR_P (decl) && DECL_DECOMPOSITION_P (decl))
6931 adc = adc_decomp_type;
6932 type = TREE_TYPE (decl) = do_auto_deduction (type, d_init, auto_node,
6933 tf_warning_or_error, adc,
6934 NULL_TREE, flags);
6935 if (type == error_mark_node)
6936 return;
6937 if (TREE_CODE (type) == FUNCTION_TYPE)
6938 {
6939 error ("initializer for %<decltype(auto) %D%> has function type "
6940 "(did you forget the %<()%> ?)", decl);
6941 TREE_TYPE (decl) = error_mark_node;
6942 return;
6943 }
6944 cp_apply_type_quals_to_decl (cp_type_quals (type), decl);
6945 }
6946
6947 if (ensure_literal_type_for_constexpr_object (decl) == error_mark_node)
6948 {
6949 DECL_DECLARED_CONSTEXPR_P (decl) = 0;
6950 if (VAR_P (decl) && DECL_CLASS_SCOPE_P (decl))
6951 {
6952 init = NULL_TREE;
6953 DECL_EXTERNAL (decl) = 1;
6954 }
6955 }
6956
6957 if (VAR_P (decl)
6958 && DECL_CLASS_SCOPE_P (decl)
6959 && DECL_INITIALIZED_IN_CLASS_P (decl))
6960 check_static_variable_definition (decl, type);
6961
6962 if (init && TREE_CODE (decl) == FUNCTION_DECL)
6963 {
6964 tree clone;
6965 if (init == ridpointers[(int)RID_DELETE])
6966 {
6967 /* FIXME check this is 1st decl. */
6968 DECL_DELETED_FN (decl) = 1;
6969 DECL_DECLARED_INLINE_P (decl) = 1;
6970 DECL_INITIAL (decl) = error_mark_node;
6971 FOR_EACH_CLONE (clone, decl)
6972 {
6973 DECL_DELETED_FN (clone) = 1;
6974 DECL_DECLARED_INLINE_P (clone) = 1;
6975 DECL_INITIAL (clone) = error_mark_node;
6976 }
6977 init = NULL_TREE;
6978 }
6979 else if (init == ridpointers[(int)RID_DEFAULT])
6980 {
6981 if (defaultable_fn_check (decl))
6982 DECL_DEFAULTED_FN (decl) = 1;
6983 else
6984 DECL_INITIAL (decl) = NULL_TREE;
6985 }
6986 }
6987
6988 if (init && VAR_P (decl))
6989 {
6990 DECL_NONTRIVIALLY_INITIALIZED_P (decl) = 1;
6991 /* If DECL is a reference, then we want to know whether init is a
6992 reference constant; init_const_expr_p as passed tells us whether
6993 it's an rvalue constant. */
6994 if (TREE_CODE (type) == REFERENCE_TYPE)
6995 init_const_expr_p = potential_constant_expression (init);
6996 if (init_const_expr_p)
6997 {
6998 /* Set these flags now for templates. We'll update the flags in
6999 store_init_value for instantiations. */
7000 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl) = 1;
7001 if (decl_maybe_constant_var_p (decl)
7002 /* FIXME setting TREE_CONSTANT on refs breaks the back end. */
7003 && TREE_CODE (type) != REFERENCE_TYPE)
7004 TREE_CONSTANT (decl) = 1;
7005 }
7006 }
7007
7008 if (processing_template_decl)
7009 {
7010 bool type_dependent_p;
7011
7012 /* Add this declaration to the statement-tree. */
7013 if (at_function_scope_p ())
7014 add_decl_expr (decl);
7015
7016 type_dependent_p = dependent_type_p (type);
7017
7018 if (check_for_bare_parameter_packs (init))
7019 {
7020 init = NULL_TREE;
7021 DECL_INITIAL (decl) = NULL_TREE;
7022 }
7023
7024 /* Generally, initializers in templates are expanded when the
7025 template is instantiated. But, if DECL is a variable constant
7026 then it can be used in future constant expressions, so its value
7027 must be available. */
7028
7029 bool dep_init = false;
7030
7031 if (!VAR_P (decl) || type_dependent_p)
7032 /* We can't do anything if the decl has dependent type. */;
7033 else if (!init && is_concept_var (decl))
7034 {
7035 error ("variable concept has no initializer");
7036 init = boolean_true_node;
7037 }
7038 else if (init
7039 && init_const_expr_p
7040 && TREE_CODE (type) != REFERENCE_TYPE
7041 && decl_maybe_constant_var_p (decl)
7042 && !(dep_init = value_dependent_init_p (init)))
7043 {
7044 /* This variable seems to be a non-dependent constant, so process
7045 its initializer. If check_initializer returns non-null the
7046 initialization wasn't constant after all. */
7047 tree init_code;
7048 cleanups = make_tree_vector ();
7049 init_code = check_initializer (decl, init, flags, &cleanups);
7050 if (init_code == NULL_TREE)
7051 init = NULL_TREE;
7052 release_tree_vector (cleanups);
7053 }
7054 else if (!DECL_PRETTY_FUNCTION_P (decl))
7055 {
7056 /* Deduce array size even if the initializer is dependent. */
7057 maybe_deduce_size_from_array_init (decl, init);
7058 /* And complain about multiple initializers. */
7059 if (init && TREE_CODE (init) == TREE_LIST && TREE_CHAIN (init)
7060 && !MAYBE_CLASS_TYPE_P (type))
7061 init = build_x_compound_expr_from_list (init, ELK_INIT,
7062 tf_warning_or_error);
7063 }
7064
7065 if (init)
7066 {
7067 if (TREE_CODE (init) == TREE_LIST)
7068 lookup_list_keep (init, true);
7069 DECL_INITIAL (decl) = init;
7070 }
7071 if (dep_init)
7072 {
7073 retrofit_lang_decl (decl);
7074 SET_DECL_DEPENDENT_INIT_P (decl, true);
7075 }
7076 return;
7077 }
7078
7079 /* Just store non-static data member initializers for later. */
7080 if (init && TREE_CODE (decl) == FIELD_DECL)
7081 DECL_INITIAL (decl) = init;
7082
7083 /* Take care of TYPE_DECLs up front. */
7084 if (TREE_CODE (decl) == TYPE_DECL)
7085 {
7086 if (type != error_mark_node
7087 && MAYBE_CLASS_TYPE_P (type) && DECL_NAME (decl))
7088 {
7089 if (TREE_TYPE (DECL_NAME (decl)) && TREE_TYPE (decl) != type)
7090 warning (0, "shadowing previous type declaration of %q#D", decl);
7091 set_identifier_type_value (DECL_NAME (decl), decl);
7092 }
7093
7094 /* If we have installed this as the canonical typedef for this
7095 type, and that type has not been defined yet, delay emitting
7096 the debug information for it, as we will emit it later. */
7097 if (TYPE_MAIN_DECL (TREE_TYPE (decl)) == decl
7098 && !COMPLETE_TYPE_P (TREE_TYPE (decl)))
7099 TYPE_DECL_SUPPRESS_DEBUG (decl) = 1;
7100
7101 rest_of_decl_compilation (decl, DECL_FILE_SCOPE_P (decl),
7102 at_eof);
7103 return;
7104 }
7105
7106 /* A reference will be modified here, as it is initialized. */
7107 if (! DECL_EXTERNAL (decl)
7108 && TREE_READONLY (decl)
7109 && TREE_CODE (type) == REFERENCE_TYPE)
7110 {
7111 was_readonly = 1;
7112 TREE_READONLY (decl) = 0;
7113 }
7114
7115 if (VAR_P (decl))
7116 {
7117 /* If this is a local variable that will need a mangled name,
7118 register it now. We must do this before processing the
7119 initializer for the variable, since the initialization might
7120 require a guard variable, and since the mangled name of the
7121 guard variable will depend on the mangled name of this
7122 variable. */
7123 if (DECL_FUNCTION_SCOPE_P (decl)
7124 && TREE_STATIC (decl)
7125 && !DECL_ARTIFICIAL (decl))
7126 {
7127 push_local_name (decl);
7128 /* Normally has_forced_label_in_static is set during GIMPLE
7129 lowering, but [cd]tors are never actually compiled directly.
7130 We need to set this early so we can deal with the label
7131 address extension. */
7132 if ((DECL_CONSTRUCTOR_P (current_function_decl)
7133 || DECL_DESTRUCTOR_P (current_function_decl))
7134 && init)
7135 {
7136 walk_tree (&init, notice_forced_label_r, NULL, NULL);
7137 add_local_decl (cfun, decl);
7138 }
7139 /* And make sure it's in the symbol table for
7140 c_parse_final_cleanups to find. */
7141 varpool_node::get_create (decl);
7142 }
7143
7144 /* Convert the initializer to the type of DECL, if we have not
7145 already initialized DECL. */
7146 if (!DECL_INITIALIZED_P (decl)
7147 /* If !DECL_EXTERNAL then DECL is being defined. In the
7148 case of a static data member initialized inside the
7149 class-specifier, there can be an initializer even if DECL
7150 is *not* defined. */
7151 && (!DECL_EXTERNAL (decl) || init))
7152 {
7153 cleanups = make_tree_vector ();
7154 init = check_initializer (decl, init, flags, &cleanups);
7155
7156 /* Handle:
7157
7158 [dcl.init]
7159
7160 The memory occupied by any object of static storage
7161 duration is zero-initialized at program startup before
7162 any other initialization takes place.
7163
7164 We cannot create an appropriate initializer until after
7165 the type of DECL is finalized. If DECL_INITIAL is set,
7166 then the DECL is statically initialized, and any
7167 necessary zero-initialization has already been performed. */
7168 if (TREE_STATIC (decl) && !DECL_INITIAL (decl))
7169 DECL_INITIAL (decl) = build_zero_init (TREE_TYPE (decl),
7170 /*nelts=*/NULL_TREE,
7171 /*static_storage_p=*/true);
7172 /* Remember that the initialization for this variable has
7173 taken place. */
7174 DECL_INITIALIZED_P (decl) = 1;
7175 /* This declaration is the definition of this variable,
7176 unless we are initializing a static data member within
7177 the class specifier. */
7178 if (!DECL_EXTERNAL (decl))
7179 var_definition_p = true;
7180 }
7181 /* If the variable has an array type, lay out the type, even if
7182 there is no initializer. It is valid to index through the
7183 array, and we must get TYPE_ALIGN set correctly on the array
7184 type. */
7185 else if (TREE_CODE (type) == ARRAY_TYPE)
7186 layout_type (type);
7187
7188 if (TREE_STATIC (decl)
7189 && !at_function_scope_p ()
7190 && current_function_decl == NULL)
7191 /* So decl is a global variable or a static member of a
7192 non local class. Record the types it uses
7193 so that we can decide later to emit debug info for them. */
7194 record_types_used_by_current_var_decl (decl);
7195 }
7196
7197 /* Add this declaration to the statement-tree. This needs to happen
7198 after the call to check_initializer so that the DECL_EXPR for a
7199 reference temp is added before the DECL_EXPR for the reference itself. */
7200 if (DECL_FUNCTION_SCOPE_P (decl))
7201 {
7202 /* If we're building a variable sized type, and we might be
7203 reachable other than via the top of the current binding
7204 level, then create a new BIND_EXPR so that we deallocate
7205 the object at the right time. */
7206 if (VAR_P (decl)
7207 && DECL_SIZE (decl)
7208 && !TREE_CONSTANT (DECL_SIZE (decl))
7209 && STATEMENT_LIST_HAS_LABEL (cur_stmt_list))
7210 {
7211 tree bind;
7212 bind = build3 (BIND_EXPR, void_type_node, NULL, NULL, NULL);
7213 TREE_SIDE_EFFECTS (bind) = 1;
7214 add_stmt (bind);
7215 BIND_EXPR_BODY (bind) = push_stmt_list ();
7216 }
7217 add_decl_expr (decl);
7218 }
7219
7220 /* Let the middle end know about variables and functions -- but not
7221 static data members in uninstantiated class templates. */
7222 if (VAR_OR_FUNCTION_DECL_P (decl))
7223 {
7224 if (VAR_P (decl))
7225 {
7226 layout_var_decl (decl);
7227 maybe_commonize_var (decl);
7228 }
7229
7230 /* This needs to happen after the linkage is set. */
7231 determine_visibility (decl);
7232
7233 if (var_definition_p && TREE_STATIC (decl))
7234 {
7235 /* If a TREE_READONLY variable needs initialization
7236 at runtime, it is no longer readonly and we need to
7237 avoid MEM_READONLY_P being set on RTL created for it. */
7238 if (init)
7239 {
7240 if (TREE_READONLY (decl))
7241 TREE_READONLY (decl) = 0;
7242 was_readonly = 0;
7243 }
7244 else if (was_readonly)
7245 TREE_READONLY (decl) = 1;
7246
7247 /* Likewise if it needs destruction. */
7248 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
7249 TREE_READONLY (decl) = 0;
7250 }
7251
7252 make_rtl_for_nonlocal_decl (decl, init, asmspec);
7253
7254 /* Check for abstractness of the type. Notice that there is no
7255 need to strip array types here since the check for those types
7256 is already done within create_array_type_for_decl. */
7257 abstract_virtuals_error (decl, type);
7258
7259 if (TREE_TYPE (decl) == error_mark_node)
7260 /* No initialization required. */
7261 ;
7262 else if (TREE_CODE (decl) == FUNCTION_DECL)
7263 {
7264 if (init)
7265 {
7266 if (init == ridpointers[(int)RID_DEFAULT])
7267 {
7268 /* An out-of-class default definition is defined at
7269 the point where it is explicitly defaulted. */
7270 if (DECL_DELETED_FN (decl))
7271 maybe_explain_implicit_delete (decl);
7272 else if (DECL_INITIAL (decl) == error_mark_node)
7273 synthesize_method (decl);
7274 }
7275 else
7276 error ("function %q#D is initialized like a variable", decl);
7277 }
7278 /* else no initialization required. */
7279 }
7280 else if (DECL_EXTERNAL (decl)
7281 && ! (DECL_LANG_SPECIFIC (decl)
7282 && DECL_NOT_REALLY_EXTERN (decl)))
7283 {
7284 if (init)
7285 DECL_INITIAL (decl) = init;
7286 }
7287 /* A variable definition. */
7288 else if (DECL_FUNCTION_SCOPE_P (decl) && !TREE_STATIC (decl))
7289 /* Initialize the local variable. */
7290 initialize_local_var (decl, init);
7291
7292 /* If a variable is defined, and then a subsequent
7293 definition with external linkage is encountered, we will
7294 get here twice for the same variable. We want to avoid
7295 calling expand_static_init more than once. For variables
7296 that are not static data members, we can call
7297 expand_static_init only when we actually process the
7298 initializer. It is not legal to redeclare a static data
7299 member, so this issue does not arise in that case. */
7300 else if (var_definition_p && TREE_STATIC (decl))
7301 expand_static_init (decl, init);
7302 }
7303
7304 /* If a CLEANUP_STMT was created to destroy a temporary bound to a
7305 reference, insert it in the statement-tree now. */
7306 if (cleanups)
7307 {
7308 unsigned i; tree t;
7309 FOR_EACH_VEC_ELT (*cleanups, i, t)
7310 push_cleanup (decl, t, false);
7311 release_tree_vector (cleanups);
7312 }
7313
7314 if (was_readonly)
7315 TREE_READONLY (decl) = 1;
7316
7317 if (flag_openmp
7318 && VAR_P (decl)
7319 && lookup_attribute ("omp declare target implicit",
7320 DECL_ATTRIBUTES (decl)))
7321 {
7322 DECL_ATTRIBUTES (decl)
7323 = remove_attribute ("omp declare target implicit",
7324 DECL_ATTRIBUTES (decl));
7325 complete_type (TREE_TYPE (decl));
7326 if (!cp_omp_mappable_type (TREE_TYPE (decl)))
7327 error ("%q+D in declare target directive does not have mappable type",
7328 decl);
7329 else if (!lookup_attribute ("omp declare target",
7330 DECL_ATTRIBUTES (decl))
7331 && !lookup_attribute ("omp declare target link",
7332 DECL_ATTRIBUTES (decl)))
7333 DECL_ATTRIBUTES (decl)
7334 = tree_cons (get_identifier ("omp declare target"),
7335 NULL_TREE, DECL_ATTRIBUTES (decl));
7336 }
7337
7338 invoke_plugin_callbacks (PLUGIN_FINISH_DECL, decl);
7339 }
7340
7341 /* For class TYPE return itself or some its bases that contain
7342 any direct non-static data members. Return error_mark_node if an
7343 error has been diagnosed. */
7344
7345 static tree
find_decomp_class_base(location_t loc,tree type,tree ret)7346 find_decomp_class_base (location_t loc, tree type, tree ret)
7347 {
7348 bool member_seen = false;
7349 for (tree field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
7350 if (TREE_CODE (field) != FIELD_DECL
7351 || DECL_ARTIFICIAL (field)
7352 || DECL_UNNAMED_BIT_FIELD (field))
7353 continue;
7354 else if (ret)
7355 return type;
7356 else if (ANON_AGGR_TYPE_P (TREE_TYPE (field)))
7357 {
7358 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE)
7359 error_at (loc, "cannot decompose class type %qT because it has an "
7360 "anonymous struct member", type);
7361 else
7362 error_at (loc, "cannot decompose class type %qT because it has an "
7363 "anonymous union member", type);
7364 inform (DECL_SOURCE_LOCATION (field), "declared here");
7365 return error_mark_node;
7366 }
7367 else if (!accessible_p (type, field, true))
7368 {
7369 error_at (loc, "cannot decompose inaccessible member %qD of %qT",
7370 field, type);
7371 inform (DECL_SOURCE_LOCATION (field),
7372 TREE_PRIVATE (field)
7373 ? G_("declared private here")
7374 : G_("declared protected here"));
7375 return error_mark_node;
7376 }
7377 else
7378 member_seen = true;
7379
7380 tree base_binfo, binfo;
7381 tree orig_ret = ret;
7382 int i;
7383 if (member_seen)
7384 ret = type;
7385 for (binfo = TYPE_BINFO (type), i = 0;
7386 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
7387 {
7388 tree t = find_decomp_class_base (loc, TREE_TYPE (base_binfo), ret);
7389 if (t == error_mark_node)
7390 return error_mark_node;
7391 if (t != NULL_TREE && t != ret)
7392 {
7393 if (ret == type)
7394 {
7395 error_at (loc, "cannot decompose class type %qT: both it and "
7396 "its base class %qT have non-static data members",
7397 type, t);
7398 return error_mark_node;
7399 }
7400 else if (orig_ret != NULL_TREE)
7401 return t;
7402 else if (ret != NULL_TREE)
7403 {
7404 error_at (loc, "cannot decompose class type %qT: its base "
7405 "classes %qT and %qT have non-static data "
7406 "members", type, ret, t);
7407 return error_mark_node;
7408 }
7409 else
7410 ret = t;
7411 }
7412 }
7413 return ret;
7414 }
7415
7416 /* Return std::tuple_size<TYPE>::value. */
7417
7418 static tree
get_tuple_size(tree type)7419 get_tuple_size (tree type)
7420 {
7421 tree args = make_tree_vec (1);
7422 TREE_VEC_ELT (args, 0) = type;
7423 tree inst = lookup_template_class (get_identifier ("tuple_size"), args,
7424 /*in_decl*/NULL_TREE,
7425 /*context*/std_node,
7426 /*entering_scope*/false, tf_none);
7427 inst = complete_type (inst);
7428 if (inst == error_mark_node || !COMPLETE_TYPE_P (inst))
7429 return NULL_TREE;
7430 tree val = lookup_qualified_name (inst, get_identifier ("value"),
7431 /*type*/false, /*complain*/false);
7432 if (TREE_CODE (val) == VAR_DECL || TREE_CODE (val) == CONST_DECL)
7433 val = maybe_constant_value (val);
7434 if (TREE_CODE (val) == INTEGER_CST)
7435 return val;
7436 else
7437 return error_mark_node;
7438 }
7439
7440 /* Return std::tuple_element<I,TYPE>::type. */
7441
7442 static tree
get_tuple_element_type(tree type,unsigned i)7443 get_tuple_element_type (tree type, unsigned i)
7444 {
7445 tree args = make_tree_vec (2);
7446 TREE_VEC_ELT (args, 0) = build_int_cst (integer_type_node, i);
7447 TREE_VEC_ELT (args, 1) = type;
7448 tree inst = lookup_template_class (get_identifier ("tuple_element"), args,
7449 /*in_decl*/NULL_TREE,
7450 /*context*/std_node,
7451 /*entering_scope*/false,
7452 tf_warning_or_error);
7453 return make_typename_type (inst, get_identifier ("type"),
7454 none_type, tf_warning_or_error);
7455 }
7456
7457 /* Return e.get<i>() or get<i>(e). */
7458
7459 static tree
get_tuple_decomp_init(tree decl,unsigned i)7460 get_tuple_decomp_init (tree decl, unsigned i)
7461 {
7462 tree get_id = get_identifier ("get");
7463 tree targs = make_tree_vec (1);
7464 TREE_VEC_ELT (targs, 0) = build_int_cst (integer_type_node, i);
7465
7466 tree etype = TREE_TYPE (decl);
7467 tree e = convert_from_reference (decl);
7468
7469 /* [The id-expression] e is an lvalue if the type of the entity e is an
7470 lvalue reference and an xvalue otherwise. */
7471 if (TREE_CODE (etype) != REFERENCE_TYPE
7472 || TYPE_REF_IS_RVALUE (etype))
7473 e = move (e);
7474
7475 tree fns = lookup_qualified_name (TREE_TYPE (e), get_id,
7476 /*type*/false, /*complain*/false);
7477 bool use_member_get = false;
7478
7479 /* To use a member get, member lookup must find at least one
7480 declaration that is a function template
7481 whose first template parameter is a non-type parameter. */
7482 for (lkp_iterator iter (MAYBE_BASELINK_FUNCTIONS (fns)); iter; ++iter)
7483 {
7484 tree fn = *iter;
7485 if (TREE_CODE (fn) == TEMPLATE_DECL)
7486 {
7487 tree tparms = DECL_TEMPLATE_PARMS (fn);
7488 tree parm = TREE_VEC_ELT (INNERMOST_TEMPLATE_PARMS (tparms), 0);
7489 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
7490 {
7491 use_member_get = true;
7492 break;
7493 }
7494 }
7495 }
7496
7497 if (use_member_get)
7498 {
7499 fns = lookup_template_function (fns, targs);
7500 return build_new_method_call (e, fns, /*args*/NULL,
7501 /*path*/NULL_TREE, LOOKUP_NORMAL,
7502 /*fn_p*/NULL, tf_warning_or_error);
7503 }
7504 else
7505 {
7506 vec<tree,va_gc> *args = make_tree_vector_single (e);
7507 fns = lookup_template_function (get_id, targs);
7508 fns = perform_koenig_lookup (fns, args, tf_warning_or_error);
7509 return finish_call_expr (fns, &args, /*novirt*/false,
7510 /*koenig*/true, tf_warning_or_error);
7511 }
7512 }
7513
7514 /* It's impossible to recover the decltype of a tuple decomposition variable
7515 based on the actual type of the variable, so store it in a hash table. */
7516
7517 static GTY((cache)) tree_cache_map *decomp_type_table;
7518 static void
store_decomp_type(tree v,tree t)7519 store_decomp_type (tree v, tree t)
7520 {
7521 if (!decomp_type_table)
7522 decomp_type_table = tree_cache_map::create_ggc (13);
7523 decomp_type_table->put (v, t);
7524 }
7525
7526 tree
lookup_decomp_type(tree v)7527 lookup_decomp_type (tree v)
7528 {
7529 return *decomp_type_table->get (v);
7530 }
7531
7532 /* Mangle a decomposition declaration if needed. Arguments like
7533 in cp_finish_decomp. */
7534
7535 void
cp_maybe_mangle_decomp(tree decl,tree first,unsigned int count)7536 cp_maybe_mangle_decomp (tree decl, tree first, unsigned int count)
7537 {
7538 if (!processing_template_decl
7539 && !error_operand_p (decl)
7540 && DECL_NAMESPACE_SCOPE_P (decl))
7541 {
7542 auto_vec<tree, 16> v;
7543 v.safe_grow (count);
7544 tree d = first;
7545 for (unsigned int i = 0; i < count; i++, d = DECL_CHAIN (d))
7546 v[count - i - 1] = d;
7547 SET_DECL_ASSEMBLER_NAME (decl, mangle_decomp (decl, v));
7548 maybe_apply_pragma_weak (decl);
7549 }
7550 }
7551
7552 /* Finish a decomposition declaration. DECL is the underlying declaration
7553 "e", FIRST is the head of a chain of decls for the individual identifiers
7554 chained through DECL_CHAIN in reverse order and COUNT is the number of
7555 those decls. */
7556
7557 void
cp_finish_decomp(tree decl,tree first,unsigned int count)7558 cp_finish_decomp (tree decl, tree first, unsigned int count)
7559 {
7560 if (error_operand_p (decl))
7561 {
7562 error_out:
7563 while (count--)
7564 {
7565 TREE_TYPE (first) = error_mark_node;
7566 if (DECL_HAS_VALUE_EXPR_P (first))
7567 {
7568 SET_DECL_VALUE_EXPR (first, NULL_TREE);
7569 DECL_HAS_VALUE_EXPR_P (first) = 0;
7570 }
7571 first = DECL_CHAIN (first);
7572 }
7573 if (DECL_P (decl) && DECL_NAMESPACE_SCOPE_P (decl))
7574 SET_DECL_ASSEMBLER_NAME (decl, get_identifier ("<decomp>"));
7575 return;
7576 }
7577
7578 location_t loc = DECL_SOURCE_LOCATION (decl);
7579 if (type_dependent_expression_p (decl)
7580 /* This happens for range for when not in templates.
7581 Still add the DECL_VALUE_EXPRs for later processing. */
7582 || (!processing_template_decl
7583 && type_uses_auto (TREE_TYPE (decl))))
7584 {
7585 for (unsigned int i = 0; i < count; i++)
7586 {
7587 if (!DECL_HAS_VALUE_EXPR_P (first))
7588 {
7589 tree v = build_nt (ARRAY_REF, decl,
7590 size_int (count - i - 1),
7591 NULL_TREE, NULL_TREE);
7592 SET_DECL_VALUE_EXPR (first, v);
7593 DECL_HAS_VALUE_EXPR_P (first) = 1;
7594 }
7595 if (processing_template_decl)
7596 fit_decomposition_lang_decl (first, decl);
7597 first = DECL_CHAIN (first);
7598 }
7599 return;
7600 }
7601
7602 auto_vec<tree, 16> v;
7603 v.safe_grow (count);
7604 tree d = first;
7605 for (unsigned int i = 0; i < count; i++, d = DECL_CHAIN (d))
7606 {
7607 v[count - i - 1] = d;
7608 fit_decomposition_lang_decl (d, decl);
7609 }
7610
7611 tree type = TREE_TYPE (decl);
7612 tree dexp = decl;
7613
7614 if (TREE_CODE (type) == REFERENCE_TYPE)
7615 {
7616 dexp = convert_from_reference (dexp);
7617 type = complete_type (TREE_TYPE (type));
7618 if (type == error_mark_node)
7619 goto error_out;
7620 if (!COMPLETE_TYPE_P (type))
7621 {
7622 error_at (loc, "structured binding refers to incomplete type %qT",
7623 type);
7624 goto error_out;
7625 }
7626 }
7627
7628 tree eltype = NULL_TREE;
7629 unsigned HOST_WIDE_INT eltscnt = 0;
7630 if (TREE_CODE (type) == ARRAY_TYPE)
7631 {
7632 tree nelts;
7633 nelts = array_type_nelts_top (type);
7634 if (nelts == error_mark_node)
7635 goto error_out;
7636 if (!tree_fits_uhwi_p (nelts))
7637 {
7638 error_at (loc, "cannot decompose variable length array %qT", type);
7639 goto error_out;
7640 }
7641 eltscnt = tree_to_uhwi (nelts);
7642 if (count != eltscnt)
7643 {
7644 cnt_mismatch:
7645 if (count > eltscnt)
7646 error_n (loc, count,
7647 "%u name provided for structured binding",
7648 "%u names provided for structured binding", count);
7649 else
7650 error_n (loc, count,
7651 "only %u name provided for structured binding",
7652 "only %u names provided for structured binding", count);
7653 inform_n (loc, eltscnt,
7654 "while %qT decomposes into %wu element",
7655 "while %qT decomposes into %wu elements",
7656 type, eltscnt);
7657 goto error_out;
7658 }
7659 eltype = TREE_TYPE (type);
7660 for (unsigned int i = 0; i < count; i++)
7661 {
7662 TREE_TYPE (v[i]) = eltype;
7663 layout_decl (v[i], 0);
7664 if (processing_template_decl)
7665 continue;
7666 tree t = unshare_expr (dexp);
7667 t = build4_loc (DECL_SOURCE_LOCATION (v[i]), ARRAY_REF,
7668 eltype, t, size_int (i), NULL_TREE,
7669 NULL_TREE);
7670 SET_DECL_VALUE_EXPR (v[i], t);
7671 DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
7672 }
7673 }
7674 /* 2 GNU extensions. */
7675 else if (TREE_CODE (type) == COMPLEX_TYPE)
7676 {
7677 eltscnt = 2;
7678 if (count != eltscnt)
7679 goto cnt_mismatch;
7680 eltype = cp_build_qualified_type (TREE_TYPE (type), TYPE_QUALS (type));
7681 for (unsigned int i = 0; i < count; i++)
7682 {
7683 TREE_TYPE (v[i]) = eltype;
7684 layout_decl (v[i], 0);
7685 if (processing_template_decl)
7686 continue;
7687 tree t = unshare_expr (dexp);
7688 t = build1_loc (DECL_SOURCE_LOCATION (v[i]),
7689 i ? IMAGPART_EXPR : REALPART_EXPR, eltype,
7690 t);
7691 SET_DECL_VALUE_EXPR (v[i], t);
7692 DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
7693 }
7694 }
7695 else if (TREE_CODE (type) == VECTOR_TYPE)
7696 {
7697 if (!TYPE_VECTOR_SUBPARTS (type).is_constant (&eltscnt))
7698 {
7699 error_at (loc, "cannot decompose variable length vector %qT", type);
7700 goto error_out;
7701 }
7702 if (count != eltscnt)
7703 goto cnt_mismatch;
7704 eltype = cp_build_qualified_type (TREE_TYPE (type), TYPE_QUALS (type));
7705 for (unsigned int i = 0; i < count; i++)
7706 {
7707 TREE_TYPE (v[i]) = eltype;
7708 layout_decl (v[i], 0);
7709 if (processing_template_decl)
7710 continue;
7711 tree t = unshare_expr (dexp);
7712 convert_vector_to_array_for_subscript (DECL_SOURCE_LOCATION (v[i]),
7713 &t, size_int (i));
7714 t = build4_loc (DECL_SOURCE_LOCATION (v[i]), ARRAY_REF,
7715 eltype, t, size_int (i), NULL_TREE,
7716 NULL_TREE);
7717 SET_DECL_VALUE_EXPR (v[i], t);
7718 DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
7719 }
7720 }
7721 else if (tree tsize = get_tuple_size (type))
7722 {
7723 if (tsize == error_mark_node)
7724 {
7725 error_at (loc, "%<std::tuple_size<%T>::value%> is not an integral "
7726 "constant expression", type);
7727 goto error_out;
7728 }
7729 if (!tree_fits_uhwi_p (tsize))
7730 {
7731 error_n (loc, count,
7732 "%u name provided for structured binding",
7733 "%u names provided for structured binding", count);
7734 inform (loc, "while %qT decomposes into %E elements",
7735 type, tsize);
7736 goto error_out;
7737 }
7738 eltscnt = tree_to_uhwi (tsize);
7739 if (count != eltscnt)
7740 goto cnt_mismatch;
7741 int save_read = DECL_READ_P (decl);
7742 for (unsigned i = 0; i < count; ++i)
7743 {
7744 location_t sloc = input_location;
7745 location_t dloc = DECL_SOURCE_LOCATION (v[i]);
7746
7747 input_location = dloc;
7748 tree init = get_tuple_decomp_init (decl, i);
7749 tree eltype = (init == error_mark_node ? error_mark_node
7750 : get_tuple_element_type (type, i));
7751 input_location = sloc;
7752
7753 if (init == error_mark_node || eltype == error_mark_node)
7754 {
7755 inform (dloc, "in initialization of structured binding "
7756 "variable %qD", v[i]);
7757 goto error_out;
7758 }
7759 /* Save the decltype away before reference collapse. */
7760 store_decomp_type (v[i], eltype);
7761 eltype = cp_build_reference_type (eltype, !lvalue_p (init));
7762 TREE_TYPE (v[i]) = eltype;
7763 layout_decl (v[i], 0);
7764 if (DECL_HAS_VALUE_EXPR_P (v[i]))
7765 {
7766 /* In this case the names are variables, not just proxies. */
7767 SET_DECL_VALUE_EXPR (v[i], NULL_TREE);
7768 DECL_HAS_VALUE_EXPR_P (v[i]) = 0;
7769 }
7770 if (!processing_template_decl)
7771 cp_finish_decl (v[i], init, /*constexpr*/false,
7772 /*asm*/NULL_TREE, LOOKUP_NORMAL);
7773 }
7774 /* Ignore reads from the underlying decl performed during initialization
7775 of the individual variables. If those will be read, we'll mark
7776 the underlying decl as read at that point. */
7777 DECL_READ_P (decl) = save_read;
7778 }
7779 else if (TREE_CODE (type) == UNION_TYPE)
7780 {
7781 error_at (loc, "cannot decompose union type %qT", type);
7782 goto error_out;
7783 }
7784 else if (!CLASS_TYPE_P (type))
7785 {
7786 error_at (loc, "cannot decompose non-array non-class type %qT", type);
7787 goto error_out;
7788 }
7789 else if (LAMBDA_TYPE_P (type))
7790 {
7791 error_at (loc, "cannot decompose lambda closure type %qT", type);
7792 goto error_out;
7793 }
7794 else if (processing_template_decl && !COMPLETE_TYPE_P (type))
7795 pedwarn (loc, 0, "structured binding refers to incomplete class type %qT",
7796 type);
7797 else
7798 {
7799 tree btype = find_decomp_class_base (loc, type, NULL_TREE);
7800 if (btype == error_mark_node)
7801 goto error_out;
7802 else if (btype == NULL_TREE)
7803 {
7804 error_at (loc, "cannot decompose class type %qT without non-static "
7805 "data members", type);
7806 goto error_out;
7807 }
7808 for (tree field = TYPE_FIELDS (btype); field; field = TREE_CHAIN (field))
7809 if (TREE_CODE (field) != FIELD_DECL
7810 || DECL_ARTIFICIAL (field)
7811 || DECL_UNNAMED_BIT_FIELD (field))
7812 continue;
7813 else
7814 eltscnt++;
7815 if (count != eltscnt)
7816 goto cnt_mismatch;
7817 tree t = dexp;
7818 if (type != btype)
7819 {
7820 t = convert_to_base (t, btype, /*check_access*/true,
7821 /*nonnull*/false, tf_warning_or_error);
7822 type = btype;
7823 }
7824 unsigned int i = 0;
7825 for (tree field = TYPE_FIELDS (btype); field; field = TREE_CHAIN (field))
7826 if (TREE_CODE (field) != FIELD_DECL
7827 || DECL_ARTIFICIAL (field)
7828 || DECL_UNNAMED_BIT_FIELD (field))
7829 continue;
7830 else
7831 {
7832 tree tt = finish_non_static_data_member (field, unshare_expr (t),
7833 NULL_TREE);
7834 if (REFERENCE_REF_P (tt))
7835 tt = TREE_OPERAND (tt, 0);
7836 TREE_TYPE (v[i]) = TREE_TYPE (tt);
7837 layout_decl (v[i], 0);
7838 if (!processing_template_decl)
7839 {
7840 SET_DECL_VALUE_EXPR (v[i], tt);
7841 DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
7842 }
7843 i++;
7844 }
7845 }
7846 if (processing_template_decl)
7847 {
7848 for (unsigned int i = 0; i < count; i++)
7849 if (!DECL_HAS_VALUE_EXPR_P (v[i]))
7850 {
7851 tree a = build_nt (ARRAY_REF, decl, size_int (i),
7852 NULL_TREE, NULL_TREE);
7853 SET_DECL_VALUE_EXPR (v[i], a);
7854 DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
7855 }
7856 }
7857 }
7858
7859 /* Returns a declaration for a VAR_DECL as if:
7860
7861 extern "C" TYPE NAME;
7862
7863 had been seen. Used to create compiler-generated global
7864 variables. */
7865
7866 static tree
declare_global_var(tree name,tree type)7867 declare_global_var (tree name, tree type)
7868 {
7869 tree decl;
7870
7871 push_to_top_level ();
7872 decl = build_decl (input_location, VAR_DECL, name, type);
7873 TREE_PUBLIC (decl) = 1;
7874 DECL_EXTERNAL (decl) = 1;
7875 DECL_ARTIFICIAL (decl) = 1;
7876 DECL_CONTEXT (decl) = FROB_CONTEXT (global_namespace);
7877 /* If the user has explicitly declared this variable (perhaps
7878 because the code we are compiling is part of a low-level runtime
7879 library), then it is possible that our declaration will be merged
7880 with theirs by pushdecl. */
7881 decl = pushdecl (decl);
7882 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
7883 pop_from_top_level ();
7884
7885 return decl;
7886 }
7887
7888 /* Returns the type for the argument to "__cxa_atexit" (or "atexit",
7889 if "__cxa_atexit" is not being used) corresponding to the function
7890 to be called when the program exits. */
7891
7892 static tree
get_atexit_fn_ptr_type(void)7893 get_atexit_fn_ptr_type (void)
7894 {
7895 tree fn_type;
7896
7897 if (!atexit_fn_ptr_type_node)
7898 {
7899 tree arg_type;
7900 if (flag_use_cxa_atexit
7901 && !targetm.cxx.use_atexit_for_cxa_atexit ())
7902 /* The parameter to "__cxa_atexit" is "void (*)(void *)". */
7903 arg_type = ptr_type_node;
7904 else
7905 /* The parameter to "atexit" is "void (*)(void)". */
7906 arg_type = NULL_TREE;
7907
7908 fn_type = build_function_type_list (void_type_node,
7909 arg_type, NULL_TREE);
7910 atexit_fn_ptr_type_node = build_pointer_type (fn_type);
7911 }
7912
7913 return atexit_fn_ptr_type_node;
7914 }
7915
7916 /* Returns a pointer to the `atexit' function. Note that if
7917 FLAG_USE_CXA_ATEXIT is nonzero, then this will actually be the new
7918 `__cxa_atexit' function specified in the IA64 C++ ABI. */
7919
7920 static tree
get_atexit_node(void)7921 get_atexit_node (void)
7922 {
7923 tree atexit_fndecl;
7924 tree fn_type;
7925 tree fn_ptr_type;
7926 const char *name;
7927 bool use_aeabi_atexit;
7928
7929 if (atexit_node)
7930 return atexit_node;
7931
7932 if (flag_use_cxa_atexit && !targetm.cxx.use_atexit_for_cxa_atexit ())
7933 {
7934 /* The declaration for `__cxa_atexit' is:
7935
7936 int __cxa_atexit (void (*)(void *), void *, void *)
7937
7938 We build up the argument types and then the function type
7939 itself. */
7940 tree argtype0, argtype1, argtype2;
7941
7942 use_aeabi_atexit = targetm.cxx.use_aeabi_atexit ();
7943 /* First, build the pointer-to-function type for the first
7944 argument. */
7945 fn_ptr_type = get_atexit_fn_ptr_type ();
7946 /* Then, build the rest of the argument types. */
7947 argtype2 = ptr_type_node;
7948 if (use_aeabi_atexit)
7949 {
7950 argtype1 = fn_ptr_type;
7951 argtype0 = ptr_type_node;
7952 }
7953 else
7954 {
7955 argtype1 = ptr_type_node;
7956 argtype0 = fn_ptr_type;
7957 }
7958 /* And the final __cxa_atexit type. */
7959 fn_type = build_function_type_list (integer_type_node,
7960 argtype0, argtype1, argtype2,
7961 NULL_TREE);
7962 if (use_aeabi_atexit)
7963 name = "__aeabi_atexit";
7964 else
7965 name = "__cxa_atexit";
7966 }
7967 else
7968 {
7969 /* The declaration for `atexit' is:
7970
7971 int atexit (void (*)());
7972
7973 We build up the argument types and then the function type
7974 itself. */
7975 fn_ptr_type = get_atexit_fn_ptr_type ();
7976 /* Build the final atexit type. */
7977 fn_type = build_function_type_list (integer_type_node,
7978 fn_ptr_type, NULL_TREE);
7979 name = "atexit";
7980 }
7981
7982 /* Now, build the function declaration. */
7983 push_lang_context (lang_name_c);
7984 atexit_fndecl = build_library_fn_ptr (name, fn_type, ECF_LEAF | ECF_NOTHROW);
7985 mark_used (atexit_fndecl);
7986 pop_lang_context ();
7987 atexit_node = decay_conversion (atexit_fndecl, tf_warning_or_error);
7988
7989 return atexit_node;
7990 }
7991
7992 /* Like get_atexit_node, but for thread-local cleanups. */
7993
7994 static tree
get_thread_atexit_node(void)7995 get_thread_atexit_node (void)
7996 {
7997 /* The declaration for `__cxa_thread_atexit' is:
7998
7999 int __cxa_thread_atexit (void (*)(void *), void *, void *) */
8000 tree fn_type = build_function_type_list (integer_type_node,
8001 get_atexit_fn_ptr_type (),
8002 ptr_type_node, ptr_type_node,
8003 NULL_TREE);
8004
8005 /* Now, build the function declaration. */
8006 tree atexit_fndecl = build_library_fn_ptr ("__cxa_thread_atexit", fn_type,
8007 ECF_LEAF | ECF_NOTHROW);
8008 return decay_conversion (atexit_fndecl, tf_warning_or_error);
8009 }
8010
8011 /* Returns the __dso_handle VAR_DECL. */
8012
8013 static tree
get_dso_handle_node(void)8014 get_dso_handle_node (void)
8015 {
8016 if (dso_handle_node)
8017 return dso_handle_node;
8018
8019 /* Declare the variable. */
8020 dso_handle_node = declare_global_var (get_identifier ("__dso_handle"),
8021 ptr_type_node);
8022
8023 #ifdef HAVE_GAS_HIDDEN
8024 if (dso_handle_node != error_mark_node)
8025 {
8026 DECL_VISIBILITY (dso_handle_node) = VISIBILITY_HIDDEN;
8027 DECL_VISIBILITY_SPECIFIED (dso_handle_node) = 1;
8028 }
8029 #endif
8030
8031 return dso_handle_node;
8032 }
8033
8034 /* Begin a new function with internal linkage whose job will be simply
8035 to destroy some particular variable. */
8036
8037 static GTY(()) int start_cleanup_cnt;
8038
8039 static tree
start_cleanup_fn(void)8040 start_cleanup_fn (void)
8041 {
8042 char name[32];
8043 tree fntype;
8044 tree fndecl;
8045 bool use_cxa_atexit = flag_use_cxa_atexit
8046 && !targetm.cxx.use_atexit_for_cxa_atexit ();
8047
8048 push_to_top_level ();
8049
8050 /* No need to mangle this. */
8051 push_lang_context (lang_name_c);
8052
8053 /* Build the name of the function. */
8054 sprintf (name, "__tcf_%d", start_cleanup_cnt++);
8055 /* Build the function declaration. */
8056 fntype = TREE_TYPE (get_atexit_fn_ptr_type ());
8057 fndecl = build_lang_decl (FUNCTION_DECL, get_identifier (name), fntype);
8058 /* It's a function with internal linkage, generated by the
8059 compiler. */
8060 TREE_PUBLIC (fndecl) = 0;
8061 DECL_ARTIFICIAL (fndecl) = 1;
8062 /* Make the function `inline' so that it is only emitted if it is
8063 actually needed. It is unlikely that it will be inlined, since
8064 it is only called via a function pointer, but we avoid unnecessary
8065 emissions this way. */
8066 DECL_DECLARED_INLINE_P (fndecl) = 1;
8067 DECL_INTERFACE_KNOWN (fndecl) = 1;
8068 /* Build the parameter. */
8069 if (use_cxa_atexit)
8070 {
8071 tree parmdecl = cp_build_parm_decl (fndecl, NULL_TREE, ptr_type_node);
8072 TREE_USED (parmdecl) = 1;
8073 DECL_READ_P (parmdecl) = 1;
8074 DECL_ARGUMENTS (fndecl) = parmdecl;
8075 }
8076
8077 pushdecl (fndecl);
8078 start_preparsed_function (fndecl, NULL_TREE, SF_PRE_PARSED);
8079
8080 pop_lang_context ();
8081
8082 return current_function_decl;
8083 }
8084
8085 /* Finish the cleanup function begun by start_cleanup_fn. */
8086
8087 static void
end_cleanup_fn(void)8088 end_cleanup_fn (void)
8089 {
8090 expand_or_defer_fn (finish_function (/*inline_p=*/false));
8091
8092 pop_from_top_level ();
8093 }
8094
8095 /* Generate code to handle the destruction of DECL, an object with
8096 static storage duration. */
8097
8098 tree
register_dtor_fn(tree decl)8099 register_dtor_fn (tree decl)
8100 {
8101 tree cleanup;
8102 tree addr;
8103 tree compound_stmt;
8104 tree fcall;
8105 tree type;
8106 bool ob_parm, dso_parm, use_dtor;
8107 tree arg0, arg1, arg2;
8108 tree atex_node;
8109
8110 type = TREE_TYPE (decl);
8111 if (TYPE_HAS_TRIVIAL_DESTRUCTOR (type))
8112 return void_node;
8113
8114 /* If we're using "__cxa_atexit" (or "__cxa_thread_atexit" or
8115 "__aeabi_atexit"), and DECL is a class object, we can just pass the
8116 destructor to "__cxa_atexit"; we don't have to build a temporary
8117 function to do the cleanup. */
8118 dso_parm = (flag_use_cxa_atexit
8119 && !targetm.cxx.use_atexit_for_cxa_atexit ());
8120 ob_parm = (CP_DECL_THREAD_LOCAL_P (decl) || dso_parm);
8121 use_dtor = ob_parm && CLASS_TYPE_P (type);
8122 if (use_dtor)
8123 {
8124 cleanup = get_class_binding (type, complete_dtor_identifier);
8125
8126 /* Make sure it is accessible. */
8127 perform_or_defer_access_check (TYPE_BINFO (type), cleanup, cleanup,
8128 tf_warning_or_error);
8129 }
8130 else
8131 {
8132 /* Call build_cleanup before we enter the anonymous function so
8133 that any access checks will be done relative to the current
8134 scope, rather than the scope of the anonymous function. */
8135 build_cleanup (decl);
8136
8137 /* Now start the function. */
8138 cleanup = start_cleanup_fn ();
8139
8140 /* Now, recompute the cleanup. It may contain SAVE_EXPRs that refer
8141 to the original function, rather than the anonymous one. That
8142 will make the back end think that nested functions are in use,
8143 which causes confusion. */
8144 push_deferring_access_checks (dk_no_check);
8145 fcall = build_cleanup (decl);
8146 pop_deferring_access_checks ();
8147
8148 /* Create the body of the anonymous function. */
8149 compound_stmt = begin_compound_stmt (BCS_FN_BODY);
8150 finish_expr_stmt (fcall);
8151 finish_compound_stmt (compound_stmt);
8152 end_cleanup_fn ();
8153 }
8154
8155 /* Call atexit with the cleanup function. */
8156 mark_used (cleanup);
8157 cleanup = build_address (cleanup);
8158
8159 if (CP_DECL_THREAD_LOCAL_P (decl))
8160 atex_node = get_thread_atexit_node ();
8161 else
8162 atex_node = get_atexit_node ();
8163
8164 if (use_dtor)
8165 {
8166 /* We must convert CLEANUP to the type that "__cxa_atexit"
8167 expects. */
8168 cleanup = build_nop (get_atexit_fn_ptr_type (), cleanup);
8169 /* "__cxa_atexit" will pass the address of DECL to the
8170 cleanup function. */
8171 mark_used (decl);
8172 addr = build_address (decl);
8173 /* The declared type of the parameter to "__cxa_atexit" is
8174 "void *". For plain "T*", we could just let the
8175 machinery in cp_build_function_call convert it -- but if the
8176 type is "cv-qualified T *", then we need to convert it
8177 before passing it in, to avoid spurious errors. */
8178 addr = build_nop (ptr_type_node, addr);
8179 }
8180 else
8181 /* Since the cleanup functions we build ignore the address
8182 they're given, there's no reason to pass the actual address
8183 in, and, in general, it's cheaper to pass NULL than any
8184 other value. */
8185 addr = null_pointer_node;
8186
8187 if (dso_parm)
8188 arg2 = cp_build_addr_expr (get_dso_handle_node (),
8189 tf_warning_or_error);
8190 else if (ob_parm)
8191 /* Just pass NULL to the dso handle parm if we don't actually
8192 have a DSO handle on this target. */
8193 arg2 = null_pointer_node;
8194 else
8195 arg2 = NULL_TREE;
8196
8197 if (ob_parm)
8198 {
8199 if (!CP_DECL_THREAD_LOCAL_P (decl)
8200 && targetm.cxx.use_aeabi_atexit ())
8201 {
8202 arg1 = cleanup;
8203 arg0 = addr;
8204 }
8205 else
8206 {
8207 arg1 = addr;
8208 arg0 = cleanup;
8209 }
8210 }
8211 else
8212 {
8213 arg0 = cleanup;
8214 arg1 = NULL_TREE;
8215 }
8216 return cp_build_function_call_nary (atex_node, tf_warning_or_error,
8217 arg0, arg1, arg2, NULL_TREE);
8218 }
8219
8220 /* DECL is a VAR_DECL with static storage duration. INIT, if present,
8221 is its initializer. Generate code to handle the construction
8222 and destruction of DECL. */
8223
8224 static void
expand_static_init(tree decl,tree init)8225 expand_static_init (tree decl, tree init)
8226 {
8227 gcc_assert (VAR_P (decl));
8228 gcc_assert (TREE_STATIC (decl));
8229
8230 /* Some variables require no dynamic initialization. */
8231 if (TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
8232 {
8233 /* Make sure the destructor is callable. */
8234 cxx_maybe_build_cleanup (decl, tf_warning_or_error);
8235 if (!init)
8236 return;
8237 }
8238
8239 if (CP_DECL_THREAD_LOCAL_P (decl) && DECL_GNU_TLS_P (decl)
8240 && !DECL_FUNCTION_SCOPE_P (decl))
8241 {
8242 if (init)
8243 error ("non-local variable %qD declared %<__thread%> "
8244 "needs dynamic initialization", decl);
8245 else
8246 error ("non-local variable %qD declared %<__thread%> "
8247 "has a non-trivial destructor", decl);
8248 static bool informed;
8249 if (!informed)
8250 {
8251 inform (DECL_SOURCE_LOCATION (decl),
8252 "C++11 %<thread_local%> allows dynamic initialization "
8253 "and destruction");
8254 informed = true;
8255 }
8256 return;
8257 }
8258
8259 if (DECL_FUNCTION_SCOPE_P (decl))
8260 {
8261 /* Emit code to perform this initialization but once. */
8262 tree if_stmt = NULL_TREE, inner_if_stmt = NULL_TREE;
8263 tree then_clause = NULL_TREE, inner_then_clause = NULL_TREE;
8264 tree guard, guard_addr;
8265 tree flag, begin;
8266 /* We don't need thread-safety code for thread-local vars. */
8267 bool thread_guard = (flag_threadsafe_statics
8268 && !CP_DECL_THREAD_LOCAL_P (decl));
8269
8270 /* Emit code to perform this initialization but once. This code
8271 looks like:
8272
8273 static <type> guard;
8274 if (!__atomic_load (guard.first_byte)) {
8275 if (__cxa_guard_acquire (&guard)) {
8276 bool flag = false;
8277 try {
8278 // Do initialization.
8279 flag = true; __cxa_guard_release (&guard);
8280 // Register variable for destruction at end of program.
8281 } catch {
8282 if (!flag) __cxa_guard_abort (&guard);
8283 }
8284 }
8285 }
8286
8287 Note that the `flag' variable is only set to 1 *after* the
8288 initialization is complete. This ensures that an exception,
8289 thrown during the construction, will cause the variable to
8290 reinitialized when we pass through this code again, as per:
8291
8292 [stmt.dcl]
8293
8294 If the initialization exits by throwing an exception, the
8295 initialization is not complete, so it will be tried again
8296 the next time control enters the declaration.
8297
8298 This process should be thread-safe, too; multiple threads
8299 should not be able to initialize the variable more than
8300 once. */
8301
8302 /* Create the guard variable. */
8303 guard = get_guard (decl);
8304
8305 /* Begin the conditional initialization. */
8306 if_stmt = begin_if_stmt ();
8307
8308 finish_if_stmt_cond (get_guard_cond (guard, thread_guard), if_stmt);
8309 then_clause = begin_compound_stmt (BCS_NO_SCOPE);
8310
8311 if (thread_guard)
8312 {
8313 tree vfntype = NULL_TREE;
8314 tree acquire_name, release_name, abort_name;
8315 tree acquire_fn, release_fn, abort_fn;
8316 guard_addr = build_address (guard);
8317
8318 acquire_name = get_identifier ("__cxa_guard_acquire");
8319 release_name = get_identifier ("__cxa_guard_release");
8320 abort_name = get_identifier ("__cxa_guard_abort");
8321 acquire_fn = get_global_binding (acquire_name);
8322 release_fn = get_global_binding (release_name);
8323 abort_fn = get_global_binding (abort_name);
8324 if (!acquire_fn)
8325 acquire_fn = push_library_fn
8326 (acquire_name, build_function_type_list (integer_type_node,
8327 TREE_TYPE (guard_addr),
8328 NULL_TREE),
8329 NULL_TREE, ECF_NOTHROW | ECF_LEAF);
8330 if (!release_fn || !abort_fn)
8331 vfntype = build_function_type_list (void_type_node,
8332 TREE_TYPE (guard_addr),
8333 NULL_TREE);
8334 if (!release_fn)
8335 release_fn = push_library_fn (release_name, vfntype, NULL_TREE,
8336 ECF_NOTHROW | ECF_LEAF);
8337 if (!abort_fn)
8338 abort_fn = push_library_fn (abort_name, vfntype, NULL_TREE,
8339 ECF_NOTHROW | ECF_LEAF);
8340
8341 inner_if_stmt = begin_if_stmt ();
8342 finish_if_stmt_cond (build_call_n (acquire_fn, 1, guard_addr),
8343 inner_if_stmt);
8344
8345 inner_then_clause = begin_compound_stmt (BCS_NO_SCOPE);
8346 begin = get_target_expr (boolean_false_node);
8347 flag = TARGET_EXPR_SLOT (begin);
8348
8349 TARGET_EXPR_CLEANUP (begin)
8350 = build3 (COND_EXPR, void_type_node, flag,
8351 void_node,
8352 build_call_n (abort_fn, 1, guard_addr));
8353 CLEANUP_EH_ONLY (begin) = 1;
8354
8355 /* Do the initialization itself. */
8356 init = add_stmt_to_compound (begin, init);
8357 init = add_stmt_to_compound
8358 (init, build2 (MODIFY_EXPR, void_type_node, flag, boolean_true_node));
8359 init = add_stmt_to_compound
8360 (init, build_call_n (release_fn, 1, guard_addr));
8361 }
8362 else
8363 init = add_stmt_to_compound (init, set_guard (guard));
8364
8365 /* Use atexit to register a function for destroying this static
8366 variable. */
8367 init = add_stmt_to_compound (init, register_dtor_fn (decl));
8368
8369 finish_expr_stmt (init);
8370
8371 if (thread_guard)
8372 {
8373 finish_compound_stmt (inner_then_clause);
8374 finish_then_clause (inner_if_stmt);
8375 finish_if_stmt (inner_if_stmt);
8376 }
8377
8378 finish_compound_stmt (then_clause);
8379 finish_then_clause (if_stmt);
8380 finish_if_stmt (if_stmt);
8381 }
8382 else if (CP_DECL_THREAD_LOCAL_P (decl))
8383 tls_aggregates = tree_cons (init, decl, tls_aggregates);
8384 else
8385 static_aggregates = tree_cons (init, decl, static_aggregates);
8386 }
8387
8388
8389 /* Make TYPE a complete type based on INITIAL_VALUE.
8390 Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered,
8391 2 if there was no information (in which case assume 0 if DO_DEFAULT),
8392 3 if the initializer list is empty (in pedantic mode). */
8393
8394 int
cp_complete_array_type(tree * ptype,tree initial_value,bool do_default)8395 cp_complete_array_type (tree *ptype, tree initial_value, bool do_default)
8396 {
8397 int failure;
8398 tree type, elt_type;
8399
8400 /* Don't get confused by a CONSTRUCTOR for some other type. */
8401 if (initial_value && TREE_CODE (initial_value) == CONSTRUCTOR
8402 && !BRACE_ENCLOSED_INITIALIZER_P (initial_value)
8403 && TREE_CODE (TREE_TYPE (initial_value)) != ARRAY_TYPE)
8404 return 1;
8405
8406 if (initial_value)
8407 {
8408 unsigned HOST_WIDE_INT i;
8409 tree value;
8410
8411 /* An array of character type can be initialized from a
8412 brace-enclosed string constant.
8413
8414 FIXME: this code is duplicated from reshape_init. Probably
8415 we should just call reshape_init here? */
8416 if (char_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (*ptype)))
8417 && TREE_CODE (initial_value) == CONSTRUCTOR
8418 && !vec_safe_is_empty (CONSTRUCTOR_ELTS (initial_value)))
8419 {
8420 vec<constructor_elt, va_gc> *v = CONSTRUCTOR_ELTS (initial_value);
8421 tree value = (*v)[0].value;
8422
8423 if (TREE_CODE (value) == STRING_CST
8424 && v->length () == 1)
8425 initial_value = value;
8426 }
8427
8428 /* If any of the elements are parameter packs, we can't actually
8429 complete this type now because the array size is dependent. */
8430 if (TREE_CODE (initial_value) == CONSTRUCTOR)
8431 {
8432 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (initial_value),
8433 i, value)
8434 {
8435 if (PACK_EXPANSION_P (value))
8436 return 0;
8437 }
8438 }
8439 }
8440
8441 failure = complete_array_type (ptype, initial_value, do_default);
8442
8443 /* We can create the array before the element type is complete, which
8444 means that we didn't have these two bits set in the original type
8445 either. In completing the type, we are expected to propagate these
8446 bits. See also complete_type which does the same thing for arrays
8447 of fixed size. */
8448 type = *ptype;
8449 if (type != error_mark_node && TYPE_DOMAIN (type))
8450 {
8451 elt_type = TREE_TYPE (type);
8452 TYPE_NEEDS_CONSTRUCTING (type) = TYPE_NEEDS_CONSTRUCTING (elt_type);
8453 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
8454 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (elt_type);
8455 }
8456
8457 return failure;
8458 }
8459
8460 /* As above, but either give an error or reject zero-size arrays, depending
8461 on COMPLAIN. */
8462
8463 int
cp_complete_array_type_or_error(tree * ptype,tree initial_value,bool do_default,tsubst_flags_t complain)8464 cp_complete_array_type_or_error (tree *ptype, tree initial_value,
8465 bool do_default, tsubst_flags_t complain)
8466 {
8467 int failure;
8468 bool sfinae = !(complain & tf_error);
8469 /* In SFINAE context we can't be lenient about zero-size arrays. */
8470 if (sfinae)
8471 ++pedantic;
8472 failure = cp_complete_array_type (ptype, initial_value, do_default);
8473 if (sfinae)
8474 --pedantic;
8475 if (failure)
8476 {
8477 if (sfinae)
8478 /* Not an error. */;
8479 else if (failure == 1)
8480 error ("initializer fails to determine size of %qT", *ptype);
8481 else if (failure == 2)
8482 {
8483 if (do_default)
8484 error ("array size missing in %qT", *ptype);
8485 }
8486 else if (failure == 3)
8487 error ("zero-size array %qT", *ptype);
8488 *ptype = error_mark_node;
8489 }
8490 return failure;
8491 }
8492
8493 /* Return zero if something is declared to be a member of type
8494 CTYPE when in the context of CUR_TYPE. STRING is the error
8495 message to print in that case. Otherwise, quietly return 1. */
8496
8497 static int
member_function_or_else(tree ctype,tree cur_type,enum overload_flags flags)8498 member_function_or_else (tree ctype, tree cur_type, enum overload_flags flags)
8499 {
8500 if (ctype && ctype != cur_type)
8501 {
8502 if (flags == DTOR_FLAG)
8503 error ("destructor for alien class %qT cannot be a member", ctype);
8504 else
8505 error ("constructor for alien class %qT cannot be a member", ctype);
8506 return 0;
8507 }
8508 return 1;
8509 }
8510
8511 /* Subroutine of `grokdeclarator'. */
8512
8513 /* Generate errors possibly applicable for a given set of specifiers.
8514 This is for ARM $7.1.2. */
8515
8516 static void
bad_specifiers(tree object,enum bad_spec_place type,int virtualp,int quals,int inlinep,int friendp,int raises)8517 bad_specifiers (tree object,
8518 enum bad_spec_place type,
8519 int virtualp,
8520 int quals,
8521 int inlinep,
8522 int friendp,
8523 int raises)
8524 {
8525 switch (type)
8526 {
8527 case BSP_VAR:
8528 if (virtualp)
8529 error ("%qD declared as a %<virtual%> variable", object);
8530 if (quals)
8531 error ("%<const%> and %<volatile%> function specifiers on "
8532 "%qD invalid in variable declaration", object);
8533 break;
8534 case BSP_PARM:
8535 if (virtualp)
8536 error ("%qD declared as a %<virtual%> parameter", object);
8537 if (inlinep)
8538 error ("%qD declared as an %<inline%> parameter", object);
8539 if (quals)
8540 error ("%<const%> and %<volatile%> function specifiers on "
8541 "%qD invalid in parameter declaration", object);
8542 break;
8543 case BSP_TYPE:
8544 if (virtualp)
8545 error ("%qD declared as a %<virtual%> type", object);
8546 if (inlinep)
8547 error ("%qD declared as an %<inline%> type", object);
8548 if (quals)
8549 error ("%<const%> and %<volatile%> function specifiers on "
8550 "%qD invalid in type declaration", object);
8551 break;
8552 case BSP_FIELD:
8553 if (virtualp)
8554 error ("%qD declared as a %<virtual%> field", object);
8555 if (inlinep)
8556 error ("%qD declared as an %<inline%> field", object);
8557 if (quals)
8558 error ("%<const%> and %<volatile%> function specifiers on "
8559 "%qD invalid in field declaration", object);
8560 break;
8561 default:
8562 gcc_unreachable();
8563 }
8564 if (friendp)
8565 error ("%q+D declared as a friend", object);
8566 if (raises
8567 && !flag_noexcept_type
8568 && (TREE_CODE (object) == TYPE_DECL
8569 || (!TYPE_PTRFN_P (TREE_TYPE (object))
8570 && !TYPE_REFFN_P (TREE_TYPE (object))
8571 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (object)))))
8572 error ("%q+D declared with an exception specification", object);
8573 }
8574
8575 /* DECL is a member function or static data member and is presently
8576 being defined. Check that the definition is taking place in a
8577 valid namespace. */
8578
8579 static void
check_class_member_definition_namespace(tree decl)8580 check_class_member_definition_namespace (tree decl)
8581 {
8582 /* These checks only apply to member functions and static data
8583 members. */
8584 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
8585 /* We check for problems with specializations in pt.c in
8586 check_specialization_namespace, where we can issue better
8587 diagnostics. */
8588 if (processing_specialization)
8589 return;
8590 /* We check this in check_explicit_instantiation_namespace. */
8591 if (processing_explicit_instantiation)
8592 return;
8593 /* [class.mfct]
8594
8595 A member function definition that appears outside of the
8596 class definition shall appear in a namespace scope enclosing
8597 the class definition.
8598
8599 [class.static.data]
8600
8601 The definition for a static data member shall appear in a
8602 namespace scope enclosing the member's class definition. */
8603 if (!is_ancestor (current_namespace, DECL_CONTEXT (decl)))
8604 permerror (input_location, "definition of %qD is not in namespace enclosing %qT",
8605 decl, DECL_CONTEXT (decl));
8606 }
8607
8608 /* Build a PARM_DECL for the "this" parameter of FN. TYPE is the
8609 METHOD_TYPE for a non-static member function; QUALS are the
8610 cv-qualifiers that apply to the function. */
8611
8612 tree
build_this_parm(tree fn,tree type,cp_cv_quals quals)8613 build_this_parm (tree fn, tree type, cp_cv_quals quals)
8614 {
8615 tree this_type;
8616 tree qual_type;
8617 tree parm;
8618 cp_cv_quals this_quals;
8619
8620 if (CLASS_TYPE_P (type))
8621 {
8622 this_type
8623 = cp_build_qualified_type (type, quals & ~TYPE_QUAL_RESTRICT);
8624 this_type = build_pointer_type (this_type);
8625 }
8626 else
8627 this_type = type_of_this_parm (type);
8628 /* The `this' parameter is implicitly `const'; it cannot be
8629 assigned to. */
8630 this_quals = (quals & TYPE_QUAL_RESTRICT) | TYPE_QUAL_CONST;
8631 qual_type = cp_build_qualified_type (this_type, this_quals);
8632 parm = build_artificial_parm (fn, this_identifier, qual_type);
8633 cp_apply_type_quals_to_decl (this_quals, parm);
8634 return parm;
8635 }
8636
8637 /* DECL is a static member function. Complain if it was declared
8638 with function-cv-quals. */
8639
8640 static void
check_static_quals(tree decl,cp_cv_quals quals)8641 check_static_quals (tree decl, cp_cv_quals quals)
8642 {
8643 if (quals != TYPE_UNQUALIFIED)
8644 error ("static member function %q#D declared with type qualifiers",
8645 decl);
8646 }
8647
8648 // Check that FN takes no arguments and returns bool.
8649 static void
check_concept_fn(tree fn)8650 check_concept_fn (tree fn)
8651 {
8652 // A constraint is nullary.
8653 if (DECL_ARGUMENTS (fn))
8654 error ("concept %q#D declared with function parameters", fn);
8655
8656 // The declared return type of the concept shall be bool, and
8657 // it shall not be deduced from it definition.
8658 tree type = TREE_TYPE (TREE_TYPE (fn));
8659 if (is_auto (type))
8660 error ("concept %q#D declared with a deduced return type", fn);
8661 else if (type != boolean_type_node)
8662 error ("concept %q#D with non-%<bool%> return type %qT", fn, type);
8663 }
8664
8665 /* Helper function. Replace the temporary this parameter injected
8666 during cp_finish_omp_declare_simd with the real this parameter. */
8667
8668 static tree
declare_simd_adjust_this(tree * tp,int * walk_subtrees,void * data)8669 declare_simd_adjust_this (tree *tp, int *walk_subtrees, void *data)
8670 {
8671 tree this_parm = (tree) data;
8672 if (TREE_CODE (*tp) == PARM_DECL
8673 && DECL_NAME (*tp) == this_identifier
8674 && *tp != this_parm)
8675 *tp = this_parm;
8676 else if (TYPE_P (*tp))
8677 *walk_subtrees = 0;
8678 return NULL_TREE;
8679 }
8680
8681 /* CTYPE is class type, or null if non-class.
8682 TYPE is type this FUNCTION_DECL should have, either FUNCTION_TYPE
8683 or METHOD_TYPE.
8684 DECLARATOR is the function's name.
8685 PARMS is a chain of PARM_DECLs for the function.
8686 VIRTUALP is truthvalue of whether the function is virtual or not.
8687 FLAGS are to be passed through to `grokclassfn'.
8688 QUALS are qualifiers indicating whether the function is `const'
8689 or `volatile'.
8690 RAISES is a list of exceptions that this function can raise.
8691 CHECK is 1 if we must find this method in CTYPE, 0 if we should
8692 not look, and -1 if we should not call `grokclassfn' at all.
8693
8694 SFK is the kind of special function (if any) for the new function.
8695
8696 Returns `NULL_TREE' if something goes wrong, after issuing
8697 applicable error messages. */
8698
8699 static tree
grokfndecl(tree ctype,tree type,tree declarator,tree parms,tree orig_declarator,tree decl_reqs,int virtualp,enum overload_flags flags,cp_cv_quals quals,cp_ref_qualifier rqual,tree raises,int check,int friendp,int publicp,int inlinep,bool deletedp,special_function_kind sfk,bool funcdef_flag,int template_count,tree in_namespace,tree * attrlist,location_t location)8700 grokfndecl (tree ctype,
8701 tree type,
8702 tree declarator,
8703 tree parms,
8704 tree orig_declarator,
8705 tree decl_reqs,
8706 int virtualp,
8707 enum overload_flags flags,
8708 cp_cv_quals quals,
8709 cp_ref_qualifier rqual,
8710 tree raises,
8711 int check,
8712 int friendp,
8713 int publicp,
8714 int inlinep,
8715 bool deletedp,
8716 special_function_kind sfk,
8717 bool funcdef_flag,
8718 int template_count,
8719 tree in_namespace,
8720 tree* attrlist,
8721 location_t location)
8722 {
8723 tree decl;
8724 int staticp = ctype && TREE_CODE (type) == FUNCTION_TYPE;
8725 tree t;
8726
8727 // Was the concept specifier present?
8728 bool concept_p = inlinep & 4;
8729
8730 // Concept declarations must have a corresponding definition.
8731 if (concept_p && !funcdef_flag)
8732 {
8733 error ("concept %qD has no definition", declarator);
8734 return NULL_TREE;
8735 }
8736
8737 if (rqual)
8738 type = build_ref_qualified_type (type, rqual);
8739 if (raises)
8740 type = build_exception_variant (type, raises);
8741
8742 decl = build_lang_decl (FUNCTION_DECL, declarator, type);
8743
8744 /* Set the constraints on the declaration. */
8745 if (flag_concepts)
8746 {
8747 tree tmpl_reqs = NULL_TREE;
8748 if (processing_template_decl > template_class_depth (ctype))
8749 tmpl_reqs = TEMPLATE_PARMS_CONSTRAINTS (current_template_parms);
8750
8751 /* Adjust the required expression into a constraint. */
8752 if (decl_reqs)
8753 decl_reqs = normalize_expression (decl_reqs);
8754
8755 tree ci = build_constraints (tmpl_reqs, decl_reqs);
8756 set_constraints (decl, ci);
8757 }
8758
8759 /* If we have an explicit location, use it, otherwise use whatever
8760 build_lang_decl used (probably input_location). */
8761 if (location != UNKNOWN_LOCATION)
8762 DECL_SOURCE_LOCATION (decl) = location;
8763
8764 if (TREE_CODE (type) == METHOD_TYPE)
8765 {
8766 tree parm = build_this_parm (decl, type, quals);
8767 DECL_CHAIN (parm) = parms;
8768 parms = parm;
8769
8770 /* Allocate space to hold the vptr bit if needed. */
8771 SET_DECL_ALIGN (decl, MINIMUM_METHOD_BOUNDARY);
8772 }
8773
8774 DECL_ARGUMENTS (decl) = parms;
8775 for (t = parms; t; t = DECL_CHAIN (t))
8776 DECL_CONTEXT (t) = decl;
8777
8778 /* Propagate volatile out from type to decl. */
8779 if (TYPE_VOLATILE (type))
8780 TREE_THIS_VOLATILE (decl) = 1;
8781
8782 /* Setup decl according to sfk. */
8783 switch (sfk)
8784 {
8785 case sfk_constructor:
8786 case sfk_copy_constructor:
8787 case sfk_move_constructor:
8788 DECL_CXX_CONSTRUCTOR_P (decl) = 1;
8789 DECL_NAME (decl) = ctor_identifier;
8790 break;
8791 case sfk_destructor:
8792 DECL_CXX_DESTRUCTOR_P (decl) = 1;
8793 DECL_NAME (decl) = dtor_identifier;
8794 break;
8795 default:
8796 break;
8797 }
8798
8799 if (friendp && TREE_CODE (orig_declarator) == TEMPLATE_ID_EXPR)
8800 {
8801 if (funcdef_flag)
8802 error ("defining explicit specialization %qD in friend declaration",
8803 orig_declarator);
8804 else
8805 {
8806 tree fns = TREE_OPERAND (orig_declarator, 0);
8807 tree args = TREE_OPERAND (orig_declarator, 1);
8808
8809 if (PROCESSING_REAL_TEMPLATE_DECL_P ())
8810 {
8811 /* Something like `template <class T> friend void f<T>()'. */
8812 error ("invalid use of template-id %qD in declaration "
8813 "of primary template",
8814 orig_declarator);
8815 return NULL_TREE;
8816 }
8817
8818
8819 /* A friend declaration of the form friend void f<>(). Record
8820 the information in the TEMPLATE_ID_EXPR. */
8821 SET_DECL_IMPLICIT_INSTANTIATION (decl);
8822
8823 gcc_assert (identifier_p (fns) || TREE_CODE (fns) == OVERLOAD);
8824 DECL_TEMPLATE_INFO (decl) = build_template_info (fns, args);
8825
8826 for (t = TYPE_ARG_TYPES (TREE_TYPE (decl)); t; t = TREE_CHAIN (t))
8827 if (TREE_PURPOSE (t)
8828 && TREE_CODE (TREE_PURPOSE (t)) == DEFAULT_ARG)
8829 {
8830 error ("default arguments are not allowed in declaration "
8831 "of friend template specialization %qD",
8832 decl);
8833 return NULL_TREE;
8834 }
8835
8836 if (inlinep & 1)
8837 {
8838 error ("%<inline%> is not allowed in declaration of friend "
8839 "template specialization %qD",
8840 decl);
8841 return NULL_TREE;
8842 }
8843 }
8844 }
8845
8846 /* If this decl has namespace scope, set that up. */
8847 if (in_namespace)
8848 set_decl_namespace (decl, in_namespace, friendp);
8849 else if (!ctype)
8850 DECL_CONTEXT (decl) = FROB_CONTEXT (current_decl_namespace ());
8851
8852 /* `main' and builtins have implicit 'C' linkage. */
8853 if (ctype == NULL_TREE
8854 && DECL_FILE_SCOPE_P (decl)
8855 && current_lang_name == lang_name_cplusplus
8856 && (MAIN_NAME_P (declarator)
8857 || (IDENTIFIER_LENGTH (declarator) > 10
8858 && IDENTIFIER_POINTER (declarator)[0] == '_'
8859 && IDENTIFIER_POINTER (declarator)[1] == '_'
8860 && strncmp (IDENTIFIER_POINTER (declarator)+2,
8861 "builtin_", 8) == 0)
8862 || (targetcm.cxx_implicit_extern_c
8863 && (targetcm.cxx_implicit_extern_c
8864 (IDENTIFIER_POINTER (declarator))))))
8865 SET_DECL_LANGUAGE (decl, lang_c);
8866
8867 /* Should probably propagate const out from type to decl I bet (mrs). */
8868 if (staticp)
8869 {
8870 DECL_STATIC_FUNCTION_P (decl) = 1;
8871 DECL_CONTEXT (decl) = ctype;
8872 }
8873
8874 if (deletedp)
8875 DECL_DELETED_FN (decl) = 1;
8876
8877 if (ctype)
8878 {
8879 DECL_CONTEXT (decl) = ctype;
8880 if (funcdef_flag)
8881 check_class_member_definition_namespace (decl);
8882 }
8883
8884 if (ctype == NULL_TREE && DECL_MAIN_P (decl))
8885 {
8886 if (PROCESSING_REAL_TEMPLATE_DECL_P())
8887 error ("cannot declare %<::main%> to be a template");
8888 if (inlinep & 1)
8889 error ("cannot declare %<::main%> to be inline");
8890 if (inlinep & 2)
8891 error ("cannot declare %<::main%> to be %<constexpr%>");
8892 if (!publicp)
8893 error ("cannot declare %<::main%> to be static");
8894 inlinep = 0;
8895 publicp = 1;
8896 }
8897
8898 /* Members of anonymous types and local classes have no linkage; make
8899 them internal. If a typedef is made later, this will be changed. */
8900 if (ctype && (!TREE_PUBLIC (TYPE_MAIN_DECL (ctype))
8901 || decl_function_context (TYPE_MAIN_DECL (ctype))))
8902 publicp = 0;
8903
8904 if (publicp && cxx_dialect == cxx98)
8905 {
8906 /* [basic.link]: A name with no linkage (notably, the name of a class
8907 or enumeration declared in a local scope) shall not be used to
8908 declare an entity with linkage.
8909
8910 DR 757 relaxes this restriction for C++0x. */
8911 no_linkage_error (decl);
8912 }
8913
8914 TREE_PUBLIC (decl) = publicp;
8915 if (! publicp)
8916 {
8917 DECL_INTERFACE_KNOWN (decl) = 1;
8918 DECL_NOT_REALLY_EXTERN (decl) = 1;
8919 }
8920
8921 /* If the declaration was declared inline, mark it as such. */
8922 if (inlinep)
8923 {
8924 DECL_DECLARED_INLINE_P (decl) = 1;
8925 if (publicp)
8926 DECL_COMDAT (decl) = 1;
8927 }
8928 if (inlinep & 2)
8929 DECL_DECLARED_CONSTEXPR_P (decl) = true;
8930
8931 // If the concept declaration specifier was found, check
8932 // that the declaration satisfies the necessary requirements.
8933 if (concept_p)
8934 {
8935 DECL_DECLARED_CONCEPT_P (decl) = true;
8936 check_concept_fn (decl);
8937 }
8938
8939 DECL_EXTERNAL (decl) = 1;
8940 if (TREE_CODE (type) == FUNCTION_TYPE)
8941 {
8942 if (quals || rqual)
8943 TREE_TYPE (decl) = apply_memfn_quals (TREE_TYPE (decl),
8944 TYPE_UNQUALIFIED,
8945 REF_QUAL_NONE);
8946
8947 if (quals)
8948 {
8949 error (ctype
8950 ? G_("static member function %qD cannot have cv-qualifier")
8951 : G_("non-member function %qD cannot have cv-qualifier"),
8952 decl);
8953 quals = TYPE_UNQUALIFIED;
8954 }
8955
8956 if (rqual)
8957 {
8958 error (ctype
8959 ? G_("static member function %qD cannot have ref-qualifier")
8960 : G_("non-member function %qD cannot have ref-qualifier"),
8961 decl);
8962 rqual = REF_QUAL_NONE;
8963 }
8964 }
8965
8966 if (deduction_guide_p (decl))
8967 {
8968 if (!DECL_NAMESPACE_SCOPE_P (decl))
8969 {
8970 error_at (location, "deduction guide %qD must be declared at "
8971 "namespace scope", decl);
8972 return NULL_TREE;
8973 }
8974 if (funcdef_flag)
8975 error_at (location,
8976 "deduction guide %qD must not have a function body", decl);
8977 }
8978 else if (IDENTIFIER_ANY_OP_P (DECL_NAME (decl))
8979 && !grok_op_properties (decl, /*complain=*/true))
8980 return NULL_TREE;
8981 else if (UDLIT_OPER_P (DECL_NAME (decl)))
8982 {
8983 bool long_long_unsigned_p;
8984 bool long_double_p;
8985 const char *suffix = NULL;
8986 /* [over.literal]/6: Literal operators shall not have C linkage. */
8987 if (DECL_LANGUAGE (decl) == lang_c)
8988 {
8989 error ("literal operator with C linkage");
8990 maybe_show_extern_c_location ();
8991 return NULL_TREE;
8992 }
8993
8994 if (DECL_NAMESPACE_SCOPE_P (decl))
8995 {
8996 if (!check_literal_operator_args (decl, &long_long_unsigned_p,
8997 &long_double_p))
8998 {
8999 error ("%qD has invalid argument list", decl);
9000 return NULL_TREE;
9001 }
9002
9003 suffix = UDLIT_OP_SUFFIX (DECL_NAME (decl));
9004 if (long_long_unsigned_p)
9005 {
9006 if (cpp_interpret_int_suffix (parse_in, suffix, strlen (suffix)))
9007 warning (0, "integer suffix %qs"
9008 " shadowed by implementation", suffix);
9009 }
9010 else if (long_double_p)
9011 {
9012 if (cpp_interpret_float_suffix (parse_in, suffix, strlen (suffix)))
9013 warning (0, "floating point suffix %qs"
9014 " shadowed by implementation", suffix);
9015 }
9016 /* 17.6.3.3.5 */
9017 if (suffix[0] != '_'
9018 && !in_system_header_at (DECL_SOURCE_LOCATION (decl))
9019 && !current_function_decl && !(friendp && !funcdef_flag))
9020 warning (OPT_Wliteral_suffix,
9021 "literal operator suffixes not preceded by %<_%>"
9022 " are reserved for future standardization");
9023 }
9024 else
9025 {
9026 error ("%qD must be a non-member function", decl);
9027 return NULL_TREE;
9028 }
9029 }
9030
9031 if (funcdef_flag)
9032 /* Make the init_value nonzero so pushdecl knows this is not
9033 tentative. error_mark_node is replaced later with the BLOCK. */
9034 DECL_INITIAL (decl) = error_mark_node;
9035
9036 if (TYPE_NOTHROW_P (type) || nothrow_libfn_p (decl))
9037 TREE_NOTHROW (decl) = 1;
9038
9039 if (flag_openmp || flag_openmp_simd)
9040 {
9041 /* Adjust "omp declare simd" attributes. */
9042 tree ods = lookup_attribute ("omp declare simd", *attrlist);
9043 if (ods)
9044 {
9045 tree attr;
9046 for (attr = ods; attr;
9047 attr = lookup_attribute ("omp declare simd", TREE_CHAIN (attr)))
9048 {
9049 if (TREE_CODE (type) == METHOD_TYPE)
9050 walk_tree (&TREE_VALUE (attr), declare_simd_adjust_this,
9051 DECL_ARGUMENTS (decl), NULL);
9052 if (TREE_VALUE (attr) != NULL_TREE)
9053 {
9054 tree cl = TREE_VALUE (TREE_VALUE (attr));
9055 cl = c_omp_declare_simd_clauses_to_numbers
9056 (DECL_ARGUMENTS (decl), cl);
9057 if (cl)
9058 TREE_VALUE (TREE_VALUE (attr)) = cl;
9059 else
9060 TREE_VALUE (attr) = NULL_TREE;
9061 }
9062 }
9063 }
9064 }
9065
9066 /* Caller will do the rest of this. */
9067 if (check < 0)
9068 return decl;
9069
9070 if (ctype != NULL_TREE)
9071 grokclassfn (ctype, decl, flags);
9072
9073 /* 12.4/3 */
9074 if (cxx_dialect >= cxx11
9075 && DECL_DESTRUCTOR_P (decl)
9076 && !TYPE_BEING_DEFINED (DECL_CONTEXT (decl))
9077 && !processing_template_decl)
9078 deduce_noexcept_on_destructor (decl);
9079
9080 decl = check_explicit_specialization (orig_declarator, decl,
9081 template_count,
9082 2 * funcdef_flag +
9083 4 * (friendp != 0) +
9084 8 * concept_p,
9085 *attrlist);
9086 if (decl == error_mark_node)
9087 return NULL_TREE;
9088
9089 if (DECL_STATIC_FUNCTION_P (decl))
9090 check_static_quals (decl, quals);
9091
9092 if (attrlist)
9093 {
9094 cplus_decl_attributes (&decl, *attrlist, 0);
9095 *attrlist = NULL_TREE;
9096 }
9097
9098 /* Check main's type after attributes have been applied. */
9099 if (ctype == NULL_TREE && DECL_MAIN_P (decl))
9100 {
9101 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
9102 integer_type_node))
9103 {
9104 tree oldtypeargs = TYPE_ARG_TYPES (TREE_TYPE (decl));
9105 tree newtype;
9106 error ("%<::main%> must return %<int%>");
9107 newtype = build_function_type (integer_type_node, oldtypeargs);
9108 TREE_TYPE (decl) = newtype;
9109 }
9110 if (warn_main)
9111 check_main_parameter_types (decl);
9112 }
9113
9114 if (ctype != NULL_TREE && check)
9115 {
9116 tree old_decl = check_classfn (ctype, decl,
9117 (processing_template_decl
9118 > template_class_depth (ctype))
9119 ? current_template_parms
9120 : NULL_TREE);
9121
9122 if (old_decl == error_mark_node)
9123 return NULL_TREE;
9124
9125 if (old_decl)
9126 {
9127 tree ok;
9128 tree pushed_scope;
9129
9130 if (TREE_CODE (old_decl) == TEMPLATE_DECL)
9131 /* Because grokfndecl is always supposed to return a
9132 FUNCTION_DECL, we pull out the DECL_TEMPLATE_RESULT
9133 here. We depend on our callers to figure out that its
9134 really a template that's being returned. */
9135 old_decl = DECL_TEMPLATE_RESULT (old_decl);
9136
9137 if (DECL_STATIC_FUNCTION_P (old_decl)
9138 && TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE)
9139 {
9140 /* Remove the `this' parm added by grokclassfn. */
9141 revert_static_member_fn (decl);
9142 check_static_quals (decl, quals);
9143 }
9144 if (DECL_ARTIFICIAL (old_decl))
9145 {
9146 error ("definition of implicitly-declared %qD", old_decl);
9147 return NULL_TREE;
9148 }
9149 else if (DECL_DEFAULTED_FN (old_decl))
9150 {
9151 error ("definition of explicitly-defaulted %q+D", decl);
9152 inform (DECL_SOURCE_LOCATION (old_decl),
9153 "%q#D explicitly defaulted here", old_decl);
9154 return NULL_TREE;
9155 }
9156
9157 /* Since we've smashed OLD_DECL to its
9158 DECL_TEMPLATE_RESULT, we must do the same to DECL. */
9159 if (TREE_CODE (decl) == TEMPLATE_DECL)
9160 decl = DECL_TEMPLATE_RESULT (decl);
9161
9162 /* Attempt to merge the declarations. This can fail, in
9163 the case of some invalid specialization declarations. */
9164 pushed_scope = push_scope (ctype);
9165 ok = duplicate_decls (decl, old_decl, friendp);
9166 if (pushed_scope)
9167 pop_scope (pushed_scope);
9168 if (!ok)
9169 {
9170 error ("no %q#D member function declared in class %qT",
9171 decl, ctype);
9172 return NULL_TREE;
9173 }
9174 if (ok == error_mark_node)
9175 return NULL_TREE;
9176 return old_decl;
9177 }
9178 }
9179
9180 if (DECL_CONSTRUCTOR_P (decl) && !grok_ctor_properties (ctype, decl))
9181 return NULL_TREE;
9182
9183 if (ctype == NULL_TREE || check)
9184 return decl;
9185
9186 if (virtualp)
9187 DECL_VIRTUAL_P (decl) = 1;
9188
9189 return decl;
9190 }
9191
9192 /* decl is a FUNCTION_DECL.
9193 specifiers are the parsed virt-specifiers.
9194
9195 Set flags to reflect the virt-specifiers.
9196
9197 Returns decl. */
9198
9199 static tree
set_virt_specifiers(tree decl,cp_virt_specifiers specifiers)9200 set_virt_specifiers (tree decl, cp_virt_specifiers specifiers)
9201 {
9202 if (decl == NULL_TREE)
9203 return decl;
9204 if (specifiers & VIRT_SPEC_OVERRIDE)
9205 DECL_OVERRIDE_P (decl) = 1;
9206 if (specifiers & VIRT_SPEC_FINAL)
9207 DECL_FINAL_P (decl) = 1;
9208 return decl;
9209 }
9210
9211 /* DECL is a VAR_DECL for a static data member. Set flags to reflect
9212 the linkage that DECL will receive in the object file. */
9213
9214 static void
set_linkage_for_static_data_member(tree decl)9215 set_linkage_for_static_data_member (tree decl)
9216 {
9217 /* A static data member always has static storage duration and
9218 external linkage. Note that static data members are forbidden in
9219 local classes -- the only situation in which a class has
9220 non-external linkage. */
9221 TREE_PUBLIC (decl) = 1;
9222 TREE_STATIC (decl) = 1;
9223 /* For non-template classes, static data members are always put
9224 out in exactly those files where they are defined, just as
9225 with ordinary namespace-scope variables. */
9226 if (!processing_template_decl)
9227 DECL_INTERFACE_KNOWN (decl) = 1;
9228 }
9229
9230 /* Create a VAR_DECL named NAME with the indicated TYPE.
9231
9232 If SCOPE is non-NULL, it is the class type or namespace containing
9233 the variable. If SCOPE is NULL, the variable should is created in
9234 the innermost enclosing scope. */
9235
9236 static tree
grokvardecl(tree type,tree name,tree orig_declarator,const cp_decl_specifier_seq * declspecs,int initialized,int type_quals,int inlinep,bool conceptp,int template_count,tree scope)9237 grokvardecl (tree type,
9238 tree name,
9239 tree orig_declarator,
9240 const cp_decl_specifier_seq *declspecs,
9241 int initialized,
9242 int type_quals,
9243 int inlinep,
9244 bool conceptp,
9245 int template_count,
9246 tree scope)
9247 {
9248 tree decl;
9249 tree explicit_scope;
9250
9251 gcc_assert (!name || identifier_p (name));
9252
9253 bool constp = (type_quals & TYPE_QUAL_CONST) != 0;
9254 bool volatilep = (type_quals & TYPE_QUAL_VOLATILE) != 0;
9255
9256 /* Compute the scope in which to place the variable, but remember
9257 whether or not that scope was explicitly specified by the user. */
9258 explicit_scope = scope;
9259 if (!scope)
9260 {
9261 /* An explicit "extern" specifier indicates a namespace-scope
9262 variable. */
9263 if (declspecs->storage_class == sc_extern)
9264 scope = current_decl_namespace ();
9265 else if (!at_function_scope_p ())
9266 scope = current_scope ();
9267 }
9268
9269 if (scope
9270 && (/* If the variable is a namespace-scope variable declared in a
9271 template, we need DECL_LANG_SPECIFIC. */
9272 (TREE_CODE (scope) == NAMESPACE_DECL && processing_template_decl)
9273 /* Similarly for namespace-scope variables with language linkage
9274 other than C++. */
9275 || (TREE_CODE (scope) == NAMESPACE_DECL
9276 && current_lang_name != lang_name_cplusplus)
9277 /* Similarly for static data members. */
9278 || TYPE_P (scope)
9279 /* Similarly for explicit specializations. */
9280 || (orig_declarator
9281 && TREE_CODE (orig_declarator) == TEMPLATE_ID_EXPR)))
9282 decl = build_lang_decl (VAR_DECL, name, type);
9283 else
9284 decl = build_decl (input_location, VAR_DECL, name, type);
9285
9286 if (explicit_scope && TREE_CODE (explicit_scope) == NAMESPACE_DECL)
9287 set_decl_namespace (decl, explicit_scope, 0);
9288 else
9289 DECL_CONTEXT (decl) = FROB_CONTEXT (scope);
9290
9291 if (declspecs->storage_class == sc_extern)
9292 {
9293 DECL_THIS_EXTERN (decl) = 1;
9294 DECL_EXTERNAL (decl) = !initialized;
9295 }
9296
9297 if (DECL_CLASS_SCOPE_P (decl))
9298 {
9299 set_linkage_for_static_data_member (decl);
9300 /* This function is only called with out-of-class definitions. */
9301 DECL_EXTERNAL (decl) = 0;
9302 check_class_member_definition_namespace (decl);
9303 }
9304 /* At top level, either `static' or no s.c. makes a definition
9305 (perhaps tentative), and absence of `static' makes it public. */
9306 else if (toplevel_bindings_p ())
9307 {
9308 TREE_PUBLIC (decl) = (declspecs->storage_class != sc_static
9309 && (DECL_THIS_EXTERN (decl)
9310 || ! constp
9311 || volatilep
9312 || inlinep));
9313 TREE_STATIC (decl) = ! DECL_EXTERNAL (decl);
9314 }
9315 /* Not at top level, only `static' makes a static definition. */
9316 else
9317 {
9318 TREE_STATIC (decl) = declspecs->storage_class == sc_static;
9319 TREE_PUBLIC (decl) = DECL_EXTERNAL (decl);
9320 }
9321
9322 if (decl_spec_seq_has_spec_p (declspecs, ds_thread))
9323 {
9324 if (DECL_EXTERNAL (decl) || TREE_STATIC (decl))
9325 {
9326 CP_DECL_THREAD_LOCAL_P (decl) = true;
9327 if (!processing_template_decl)
9328 set_decl_tls_model (decl, decl_default_tls_model (decl));
9329 }
9330 if (declspecs->gnu_thread_keyword_p)
9331 SET_DECL_GNU_TLS_P (decl);
9332 }
9333
9334 /* If the type of the decl has no linkage, make sure that we'll
9335 notice that in mark_used. */
9336 if (cxx_dialect > cxx98
9337 && decl_linkage (decl) != lk_none
9338 && DECL_LANG_SPECIFIC (decl) == NULL
9339 && !DECL_EXTERN_C_P (decl)
9340 && no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false))
9341 retrofit_lang_decl (decl);
9342
9343 if (TREE_PUBLIC (decl))
9344 {
9345 /* [basic.link]: A name with no linkage (notably, the name of a class
9346 or enumeration declared in a local scope) shall not be used to
9347 declare an entity with linkage.
9348
9349 DR 757 relaxes this restriction for C++0x. */
9350 if (cxx_dialect < cxx11)
9351 no_linkage_error (decl);
9352 }
9353 else
9354 DECL_INTERFACE_KNOWN (decl) = 1;
9355
9356 if (DECL_NAME (decl)
9357 && MAIN_NAME_P (DECL_NAME (decl))
9358 && scope == global_namespace)
9359 error ("cannot declare %<::main%> to be a global variable");
9360
9361 /* Check that the variable can be safely declared as a concept.
9362 Note that this also forbids explicit specializations. */
9363 if (conceptp)
9364 {
9365 if (!processing_template_decl)
9366 {
9367 error ("a non-template variable cannot be %<concept%>");
9368 return NULL_TREE;
9369 }
9370 else
9371 DECL_DECLARED_CONCEPT_P (decl) = true;
9372 if (!same_type_ignoring_top_level_qualifiers_p (type, boolean_type_node))
9373 error_at (declspecs->locations[ds_type_spec],
9374 "concept must have type %<bool%>");
9375 }
9376 else if (flag_concepts
9377 && processing_template_decl > template_class_depth (scope))
9378 {
9379 tree reqs = TEMPLATE_PARMS_CONSTRAINTS (current_template_parms);
9380 tree ci = build_constraints (reqs, NULL_TREE);
9381 set_constraints (decl, ci);
9382 }
9383
9384 // Handle explicit specializations and instantiations of variable templates.
9385 if (orig_declarator)
9386 decl = check_explicit_specialization (orig_declarator, decl,
9387 template_count, conceptp * 8);
9388
9389 return decl != error_mark_node ? decl : NULL_TREE;
9390 }
9391
9392 /* Create and return a canonical pointer to member function type, for
9393 TYPE, which is a POINTER_TYPE to a METHOD_TYPE. */
9394
9395 tree
build_ptrmemfunc_type(tree type)9396 build_ptrmemfunc_type (tree type)
9397 {
9398 tree field, fields;
9399 tree t;
9400
9401 if (type == error_mark_node)
9402 return type;
9403
9404 /* Make sure that we always have the unqualified pointer-to-member
9405 type first. */
9406 if (cp_cv_quals quals = cp_type_quals (type))
9407 {
9408 tree unqual = build_ptrmemfunc_type (TYPE_MAIN_VARIANT (type));
9409 return cp_build_qualified_type (unqual, quals);
9410 }
9411
9412 /* If a canonical type already exists for this type, use it. We use
9413 this method instead of type_hash_canon, because it only does a
9414 simple equality check on the list of field members. */
9415
9416 t = TYPE_PTRMEMFUNC_TYPE (type);
9417 if (t)
9418 return t;
9419
9420 t = make_node (RECORD_TYPE);
9421
9422 /* Let the front end know this is a pointer to member function. */
9423 TYPE_PTRMEMFUNC_FLAG (t) = 1;
9424
9425 field = build_decl (input_location, FIELD_DECL, pfn_identifier, type);
9426 fields = field;
9427
9428 field = build_decl (input_location, FIELD_DECL, delta_identifier,
9429 delta_type_node);
9430 DECL_CHAIN (field) = fields;
9431 fields = field;
9432
9433 finish_builtin_struct (t, "__ptrmemfunc_type", fields, ptr_type_node);
9434
9435 /* Zap out the name so that the back end will give us the debugging
9436 information for this anonymous RECORD_TYPE. */
9437 TYPE_NAME (t) = NULL_TREE;
9438
9439 /* Cache this pointer-to-member type so that we can find it again
9440 later. */
9441 TYPE_PTRMEMFUNC_TYPE (type) = t;
9442
9443 if (TYPE_STRUCTURAL_EQUALITY_P (type))
9444 SET_TYPE_STRUCTURAL_EQUALITY (t);
9445 else if (TYPE_CANONICAL (type) != type)
9446 TYPE_CANONICAL (t) = build_ptrmemfunc_type (TYPE_CANONICAL (type));
9447
9448 return t;
9449 }
9450
9451 /* Create and return a pointer to data member type. */
9452
9453 tree
build_ptrmem_type(tree class_type,tree member_type)9454 build_ptrmem_type (tree class_type, tree member_type)
9455 {
9456 if (TREE_CODE (member_type) == METHOD_TYPE)
9457 {
9458 cp_cv_quals quals = type_memfn_quals (member_type);
9459 cp_ref_qualifier rqual = type_memfn_rqual (member_type);
9460 member_type = build_memfn_type (member_type, class_type, quals, rqual);
9461 return build_ptrmemfunc_type (build_pointer_type (member_type));
9462 }
9463 else
9464 {
9465 gcc_assert (TREE_CODE (member_type) != FUNCTION_TYPE);
9466 return build_offset_type (class_type, member_type);
9467 }
9468 }
9469
9470 /* DECL is a VAR_DECL defined in-class, whose TYPE is also given.
9471 Check to see that the definition is valid. Issue appropriate error
9472 messages. Return 1 if the definition is particularly bad, or 0
9473 otherwise. */
9474
9475 static int
check_static_variable_definition(tree decl,tree type)9476 check_static_variable_definition (tree decl, tree type)
9477 {
9478 /* Avoid redundant diagnostics on out-of-class definitions. */
9479 if (!current_class_type || !TYPE_BEING_DEFINED (current_class_type))
9480 return 0;
9481 /* Can't check yet if we don't know the type. */
9482 if (dependent_type_p (type))
9483 return 0;
9484 /* If DECL is declared constexpr, we'll do the appropriate checks
9485 in check_initializer. Similarly for inline static data members. */
9486 if (DECL_P (decl)
9487 && (DECL_DECLARED_CONSTEXPR_P (decl)
9488 || DECL_VAR_DECLARED_INLINE_P (decl)))
9489 return 0;
9490 else if (cxx_dialect >= cxx11 && !INTEGRAL_OR_ENUMERATION_TYPE_P (type))
9491 {
9492 if (!COMPLETE_TYPE_P (type))
9493 error_at (DECL_SOURCE_LOCATION (decl),
9494 "in-class initialization of static data member %q#D of "
9495 "incomplete type", decl);
9496 else if (literal_type_p (type))
9497 permerror (DECL_SOURCE_LOCATION (decl),
9498 "%<constexpr%> needed for in-class initialization of "
9499 "static data member %q#D of non-integral type", decl);
9500 else
9501 error_at (DECL_SOURCE_LOCATION (decl),
9502 "in-class initialization of static data member %q#D of "
9503 "non-literal type", decl);
9504 return 1;
9505 }
9506
9507 /* Motion 10 at San Diego: If a static const integral data member is
9508 initialized with an integral constant expression, the initializer
9509 may appear either in the declaration (within the class), or in
9510 the definition, but not both. If it appears in the class, the
9511 member is a member constant. The file-scope definition is always
9512 required. */
9513 if (!ARITHMETIC_TYPE_P (type) && TREE_CODE (type) != ENUMERAL_TYPE)
9514 {
9515 error_at (DECL_SOURCE_LOCATION (decl),
9516 "invalid in-class initialization of static data member "
9517 "of non-integral type %qT",
9518 type);
9519 return 1;
9520 }
9521 else if (!CP_TYPE_CONST_P (type))
9522 error_at (DECL_SOURCE_LOCATION (decl),
9523 "ISO C++ forbids in-class initialization of non-const "
9524 "static member %qD",
9525 decl);
9526 else if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
9527 pedwarn (DECL_SOURCE_LOCATION (decl), OPT_Wpedantic,
9528 "ISO C++ forbids initialization of member constant "
9529 "%qD of non-integral type %qT", decl, type);
9530
9531 return 0;
9532 }
9533
9534 /* *expr_p is part of the TYPE_SIZE of a variably-sized array. If any
9535 SAVE_EXPRs in *expr_p wrap expressions with side-effects, break those
9536 expressions out into temporary variables so that walk_tree doesn't
9537 step into them (c++/15764). */
9538
9539 static tree
stabilize_save_expr_r(tree * expr_p,int * walk_subtrees,void * data)9540 stabilize_save_expr_r (tree *expr_p, int *walk_subtrees, void *data)
9541 {
9542 hash_set<tree> *pset = (hash_set<tree> *)data;
9543 tree expr = *expr_p;
9544 if (TREE_CODE (expr) == SAVE_EXPR)
9545 {
9546 tree op = TREE_OPERAND (expr, 0);
9547 cp_walk_tree (&op, stabilize_save_expr_r, data, pset);
9548 if (TREE_SIDE_EFFECTS (op))
9549 TREE_OPERAND (expr, 0) = get_temp_regvar (TREE_TYPE (op), op);
9550 *walk_subtrees = 0;
9551 }
9552 else if (!EXPR_P (expr) || !TREE_SIDE_EFFECTS (expr))
9553 *walk_subtrees = 0;
9554 return NULL;
9555 }
9556
9557 /* Entry point for the above. */
9558
9559 static void
stabilize_vla_size(tree size)9560 stabilize_vla_size (tree size)
9561 {
9562 hash_set<tree> pset;
9563 /* Break out any function calls into temporary variables. */
9564 cp_walk_tree (&size, stabilize_save_expr_r, &pset, &pset);
9565 }
9566
9567 /* Reduce a SIZEOF_EXPR to its value. */
9568
9569 tree
fold_sizeof_expr(tree t)9570 fold_sizeof_expr (tree t)
9571 {
9572 tree r;
9573 if (SIZEOF_EXPR_TYPE_P (t))
9574 r = cxx_sizeof_or_alignof_type (TREE_TYPE (TREE_OPERAND (t, 0)),
9575 SIZEOF_EXPR, false, false);
9576 else if (TYPE_P (TREE_OPERAND (t, 0)))
9577 r = cxx_sizeof_or_alignof_type (TREE_OPERAND (t, 0), SIZEOF_EXPR,
9578 false, false);
9579 else
9580 r = cxx_sizeof_or_alignof_expr (TREE_OPERAND (t, 0), SIZEOF_EXPR,
9581 false);
9582 if (r == error_mark_node)
9583 r = size_one_node;
9584 return r;
9585 }
9586
9587 /* Given the SIZE (i.e., number of elements) in an array, compute
9588 an appropriate index type for the array. If non-NULL, NAME is
9589 the name of the entity being declared. */
9590
9591 tree
compute_array_index_type(tree name,tree size,tsubst_flags_t complain)9592 compute_array_index_type (tree name, tree size, tsubst_flags_t complain)
9593 {
9594 tree itype;
9595 tree osize = size;
9596
9597 if (error_operand_p (size))
9598 return error_mark_node;
9599
9600 if (!type_dependent_expression_p (size))
9601 {
9602 osize = size = mark_rvalue_use (size);
9603
9604 if (cxx_dialect < cxx11 && TREE_CODE (size) == NOP_EXPR
9605 && TREE_SIDE_EFFECTS (size))
9606 /* In C++98, we mark a non-constant array bound with a magic
9607 NOP_EXPR with TREE_SIDE_EFFECTS; don't fold in that case. */;
9608 else
9609 {
9610 size = instantiate_non_dependent_expr_sfinae (size, complain);
9611 size = build_converted_constant_expr (size_type_node, size, complain);
9612 size = maybe_constant_value (size);
9613
9614 if (!TREE_CONSTANT (size))
9615 size = osize;
9616 }
9617
9618 if (error_operand_p (size))
9619 return error_mark_node;
9620
9621 /* The array bound must be an integer type. */
9622 tree type = TREE_TYPE (size);
9623 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
9624 {
9625 if (!(complain & tf_error))
9626 return error_mark_node;
9627 if (name)
9628 error ("size of array %qD has non-integral type %qT", name, type);
9629 else
9630 error ("size of array has non-integral type %qT", type);
9631 size = integer_one_node;
9632 }
9633 }
9634
9635 /* A type is dependent if it is...an array type constructed from any
9636 dependent type or whose size is specified by a constant expression
9637 that is value-dependent. */
9638 /* We can only call value_dependent_expression_p on integral constant
9639 expressions; treat non-constant expressions as dependent, too. */
9640 if (processing_template_decl
9641 && (type_dependent_expression_p (size)
9642 || !TREE_CONSTANT (size) || value_dependent_expression_p (size)))
9643 {
9644 /* We cannot do any checking for a SIZE that isn't known to be
9645 constant. Just build the index type and mark that it requires
9646 structural equality checks. */
9647 itype = build_index_type (build_min (MINUS_EXPR, sizetype,
9648 size, size_one_node));
9649 TYPE_DEPENDENT_P (itype) = 1;
9650 TYPE_DEPENDENT_P_VALID (itype) = 1;
9651 SET_TYPE_STRUCTURAL_EQUALITY (itype);
9652 return itype;
9653 }
9654
9655 if (TREE_CODE (size) != INTEGER_CST)
9656 {
9657 tree folded = cp_fully_fold (size);
9658 if (TREE_CODE (folded) == INTEGER_CST)
9659 pedwarn (location_of (size), OPT_Wpedantic,
9660 "size of array is not an integral constant-expression");
9661 /* Use the folded result for VLAs, too; it will have resolved
9662 SIZEOF_EXPR. */
9663 size = folded;
9664 }
9665
9666 /* Normally, the array-bound will be a constant. */
9667 if (TREE_CODE (size) == INTEGER_CST)
9668 {
9669 /* An array must have a positive number of elements. */
9670 if (!valid_constant_size_p (size))
9671 {
9672 if (!(complain & tf_error))
9673 return error_mark_node;
9674
9675 if (name)
9676 error ("size of array %qD is negative", name);
9677 else
9678 error ("size of array is negative");
9679 size = integer_one_node;
9680 }
9681 /* As an extension we allow zero-sized arrays. */
9682 else if (integer_zerop (size))
9683 {
9684 if (!(complain & tf_error))
9685 /* We must fail if performing argument deduction (as
9686 indicated by the state of complain), so that
9687 another substitution can be found. */
9688 return error_mark_node;
9689 else if (in_system_header_at (input_location))
9690 /* Allow them in system headers because glibc uses them. */;
9691 else if (name)
9692 pedwarn (input_location, OPT_Wpedantic, "ISO C++ forbids zero-size array %qD", name);
9693 else
9694 pedwarn (input_location, OPT_Wpedantic, "ISO C++ forbids zero-size array");
9695 }
9696 }
9697 else if (TREE_CONSTANT (size)
9698 /* We don't allow VLAs at non-function scopes, or during
9699 tentative template substitution. */
9700 || !at_function_scope_p ()
9701 || !(complain & tf_error))
9702 {
9703 if (!(complain & tf_error))
9704 return error_mark_node;
9705 /* `(int) &fn' is not a valid array bound. */
9706 if (name)
9707 error ("size of array %qD is not an integral constant-expression",
9708 name);
9709 else
9710 error ("size of array is not an integral constant-expression");
9711 size = integer_one_node;
9712 }
9713 else if (pedantic && warn_vla != 0)
9714 {
9715 if (name)
9716 pedwarn (input_location, OPT_Wvla, "ISO C++ forbids variable length array %qD", name);
9717 else
9718 pedwarn (input_location, OPT_Wvla, "ISO C++ forbids variable length array");
9719 }
9720 else if (warn_vla > 0)
9721 {
9722 if (name)
9723 warning (OPT_Wvla,
9724 "variable length array %qD is used", name);
9725 else
9726 warning (OPT_Wvla,
9727 "variable length array is used");
9728 }
9729
9730 if (processing_template_decl && !TREE_CONSTANT (size))
9731 /* A variable sized array. */
9732 itype = build_min (MINUS_EXPR, sizetype, size, integer_one_node);
9733 else
9734 {
9735 /* Compute the index of the largest element in the array. It is
9736 one less than the number of elements in the array. We save
9737 and restore PROCESSING_TEMPLATE_DECL so that computations in
9738 cp_build_binary_op will be appropriately folded. */
9739 {
9740 processing_template_decl_sentinel s;
9741 itype = cp_build_binary_op (input_location,
9742 MINUS_EXPR,
9743 cp_convert (ssizetype, size, complain),
9744 cp_convert (ssizetype, integer_one_node,
9745 complain),
9746 complain);
9747 itype = maybe_constant_value (itype);
9748 }
9749
9750 if (!TREE_CONSTANT (itype))
9751 {
9752 /* A variable sized array. */
9753 itype = variable_size (itype);
9754
9755 stabilize_vla_size (itype);
9756
9757 if (sanitize_flags_p (SANITIZE_VLA)
9758 && current_function_decl != NULL_TREE)
9759 {
9760 /* We have to add 1 -- in the ubsan routine we generate
9761 LE_EXPR rather than LT_EXPR. */
9762 tree t = fold_build2 (PLUS_EXPR, TREE_TYPE (itype), itype,
9763 build_one_cst (TREE_TYPE (itype)));
9764 t = ubsan_instrument_vla (input_location, t);
9765 finish_expr_stmt (t);
9766 }
9767 }
9768 /* Make sure that there was no overflow when creating to a signed
9769 index type. (For example, on a 32-bit machine, an array with
9770 size 2^32 - 1 is too big.) */
9771 else if (TREE_CODE (itype) == INTEGER_CST
9772 && TREE_OVERFLOW (itype))
9773 {
9774 if (!(complain & tf_error))
9775 return error_mark_node;
9776 error ("overflow in array dimension");
9777 TREE_OVERFLOW (itype) = 0;
9778 }
9779 }
9780
9781 /* Create and return the appropriate index type. */
9782 itype = build_index_type (itype);
9783
9784 /* If the index type were dependent, we would have returned early, so
9785 remember that it isn't. */
9786 TYPE_DEPENDENT_P (itype) = 0;
9787 TYPE_DEPENDENT_P_VALID (itype) = 1;
9788 return itype;
9789 }
9790
9791 /* Returns the scope (if any) in which the entity declared by
9792 DECLARATOR will be located. If the entity was declared with an
9793 unqualified name, NULL_TREE is returned. */
9794
9795 tree
get_scope_of_declarator(const cp_declarator * declarator)9796 get_scope_of_declarator (const cp_declarator *declarator)
9797 {
9798 while (declarator && declarator->kind != cdk_id)
9799 declarator = declarator->declarator;
9800
9801 /* If the declarator-id is a SCOPE_REF, the scope in which the
9802 declaration occurs is the first operand. */
9803 if (declarator
9804 && declarator->u.id.qualifying_scope)
9805 return declarator->u.id.qualifying_scope;
9806
9807 /* Otherwise, the declarator is not a qualified name; the entity will
9808 be declared in the current scope. */
9809 return NULL_TREE;
9810 }
9811
9812 /* Returns an ARRAY_TYPE for an array with SIZE elements of the
9813 indicated TYPE. If non-NULL, NAME is the NAME of the declaration
9814 with this type. */
9815
9816 static tree
create_array_type_for_decl(tree name,tree type,tree size)9817 create_array_type_for_decl (tree name, tree type, tree size)
9818 {
9819 tree itype = NULL_TREE;
9820
9821 /* If things have already gone awry, bail now. */
9822 if (type == error_mark_node || size == error_mark_node)
9823 return error_mark_node;
9824
9825 /* 8.3.4/1: If the type of the identifier of D contains the auto
9826 type-specifier, the program is ill-formed. */
9827 if (type_uses_auto (type))
9828 {
9829 error ("%qD declared as array of %qT", name, type);
9830 return error_mark_node;
9831 }
9832
9833 /* If there are some types which cannot be array elements,
9834 issue an error-message and return. */
9835 switch (TREE_CODE (type))
9836 {
9837 case VOID_TYPE:
9838 if (name)
9839 error ("declaration of %qD as array of void", name);
9840 else
9841 error ("creating array of void");
9842 return error_mark_node;
9843
9844 case FUNCTION_TYPE:
9845 if (name)
9846 error ("declaration of %qD as array of functions", name);
9847 else
9848 error ("creating array of functions");
9849 return error_mark_node;
9850
9851 case REFERENCE_TYPE:
9852 if (name)
9853 error ("declaration of %qD as array of references", name);
9854 else
9855 error ("creating array of references");
9856 return error_mark_node;
9857
9858 case METHOD_TYPE:
9859 if (name)
9860 error ("declaration of %qD as array of function members", name);
9861 else
9862 error ("creating array of function members");
9863 return error_mark_node;
9864
9865 default:
9866 break;
9867 }
9868
9869 /* [dcl.array]
9870
9871 The constant expressions that specify the bounds of the arrays
9872 can be omitted only for the first member of the sequence. */
9873 if (TREE_CODE (type) == ARRAY_TYPE && !TYPE_DOMAIN (type))
9874 {
9875 if (name)
9876 error ("declaration of %qD as multidimensional array must "
9877 "have bounds for all dimensions except the first",
9878 name);
9879 else
9880 error ("multidimensional array must have bounds for all "
9881 "dimensions except the first");
9882
9883 return error_mark_node;
9884 }
9885
9886 /* Figure out the index type for the array. */
9887 if (size)
9888 itype = compute_array_index_type (name, size, tf_warning_or_error);
9889
9890 /* [dcl.array]
9891 T is called the array element type; this type shall not be [...] an
9892 abstract class type. */
9893 abstract_virtuals_error (name, type);
9894
9895 return build_cplus_array_type (type, itype);
9896 }
9897
9898 /* Returns the smallest location != UNKNOWN_LOCATION among the
9899 three stored in LOCATIONS[ds_const], LOCATIONS[ds_volatile],
9900 and LOCATIONS[ds_restrict]. */
9901
9902 static location_t
smallest_type_quals_location(int type_quals,const location_t * locations)9903 smallest_type_quals_location (int type_quals, const location_t* locations)
9904 {
9905 location_t loc = UNKNOWN_LOCATION;
9906
9907 if (type_quals & TYPE_QUAL_CONST)
9908 loc = locations[ds_const];
9909
9910 if ((type_quals & TYPE_QUAL_VOLATILE)
9911 && (loc == UNKNOWN_LOCATION || locations[ds_volatile] < loc))
9912 loc = locations[ds_volatile];
9913
9914 if ((type_quals & TYPE_QUAL_RESTRICT)
9915 && (loc == UNKNOWN_LOCATION || locations[ds_restrict] < loc))
9916 loc = locations[ds_restrict];
9917
9918 return loc;
9919 }
9920
9921 /* Check that it's OK to declare a function with the indicated TYPE
9922 and TYPE_QUALS. SFK indicates the kind of special function (if any)
9923 that this function is. OPTYPE is the type given in a conversion
9924 operator declaration, or the class type for a constructor/destructor.
9925 Returns the actual return type of the function; that may be different
9926 than TYPE if an error occurs, or for certain special functions. */
9927
9928 static tree
check_special_function_return_type(special_function_kind sfk,tree type,tree optype,int type_quals,const location_t * locations)9929 check_special_function_return_type (special_function_kind sfk,
9930 tree type,
9931 tree optype,
9932 int type_quals,
9933 const location_t* locations)
9934 {
9935 switch (sfk)
9936 {
9937 case sfk_constructor:
9938 if (type)
9939 error ("return type specification for constructor invalid");
9940 else if (type_quals != TYPE_UNQUALIFIED)
9941 error_at (smallest_type_quals_location (type_quals, locations),
9942 "qualifiers are not allowed on constructor declaration");
9943
9944 if (targetm.cxx.cdtor_returns_this ())
9945 type = build_pointer_type (optype);
9946 else
9947 type = void_type_node;
9948 break;
9949
9950 case sfk_destructor:
9951 if (type)
9952 error ("return type specification for destructor invalid");
9953 else if (type_quals != TYPE_UNQUALIFIED)
9954 error_at (smallest_type_quals_location (type_quals, locations),
9955 "qualifiers are not allowed on destructor declaration");
9956
9957 /* We can't use the proper return type here because we run into
9958 problems with ambiguous bases and covariant returns. */
9959 if (targetm.cxx.cdtor_returns_this ())
9960 type = build_pointer_type (void_type_node);
9961 else
9962 type = void_type_node;
9963 break;
9964
9965 case sfk_conversion:
9966 if (type)
9967 error ("return type specified for %<operator %T%>", optype);
9968 else if (type_quals != TYPE_UNQUALIFIED)
9969 error_at (smallest_type_quals_location (type_quals, locations),
9970 "qualifiers are not allowed on declaration of "
9971 "%<operator %T%>", optype);
9972
9973 type = optype;
9974 break;
9975
9976 case sfk_deduction_guide:
9977 if (type)
9978 error ("return type specified for deduction guide");
9979 else if (type_quals != TYPE_UNQUALIFIED)
9980 error_at (smallest_type_quals_location (type_quals, locations),
9981 "qualifiers are not allowed on declaration of "
9982 "deduction guide");
9983 if (TREE_CODE (optype) == TEMPLATE_TEMPLATE_PARM)
9984 {
9985 error ("template template parameter %qT in declaration of "
9986 "deduction guide", optype);
9987 type = error_mark_node;
9988 }
9989 else
9990 type = make_template_placeholder (CLASSTYPE_TI_TEMPLATE (optype));
9991 for (int i = 0; i < ds_last; ++i)
9992 if (i != ds_explicit && locations[i])
9993 error_at (locations[i],
9994 "decl-specifier in declaration of deduction guide");
9995 break;
9996
9997 default:
9998 gcc_unreachable ();
9999 }
10000
10001 return type;
10002 }
10003
10004 /* A variable or data member (whose unqualified name is IDENTIFIER)
10005 has been declared with the indicated TYPE. If the TYPE is not
10006 acceptable, issue an error message and return a type to use for
10007 error-recovery purposes. */
10008
10009 tree
check_var_type(tree identifier,tree type)10010 check_var_type (tree identifier, tree type)
10011 {
10012 if (VOID_TYPE_P (type))
10013 {
10014 if (!identifier)
10015 error ("unnamed variable or field declared void");
10016 else if (identifier_p (identifier))
10017 {
10018 gcc_assert (!IDENTIFIER_ANY_OP_P (identifier));
10019 error ("variable or field %qE declared void", identifier);
10020 }
10021 else
10022 error ("variable or field declared void");
10023 type = error_mark_node;
10024 }
10025
10026 return type;
10027 }
10028
10029 /* Handle declaring DECL as an inline variable. */
10030
10031 static void
mark_inline_variable(tree decl)10032 mark_inline_variable (tree decl)
10033 {
10034 bool inlinep = true;
10035 if (! toplevel_bindings_p ())
10036 {
10037 error ("%<inline%> specifier invalid for variable "
10038 "%qD declared at block scope", decl);
10039 inlinep = false;
10040 }
10041 else if (cxx_dialect < cxx17)
10042 pedwarn (DECL_SOURCE_LOCATION (decl), 0,
10043 "inline variables are only available "
10044 "with -std=c++17 or -std=gnu++17");
10045 if (inlinep)
10046 {
10047 retrofit_lang_decl (decl);
10048 SET_DECL_VAR_DECLARED_INLINE_P (decl);
10049 }
10050 }
10051
10052
10053 /* Assign a typedef-given name to a class or enumeration type declared
10054 as anonymous at first. This was split out of grokdeclarator
10055 because it is also used in libcc1. */
10056
10057 void
name_unnamed_type(tree type,tree decl)10058 name_unnamed_type (tree type, tree decl)
10059 {
10060 gcc_assert (TYPE_UNNAMED_P (type));
10061
10062 /* Replace the anonymous name with the real name everywhere. */
10063 for (tree t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
10064 {
10065 if (anon_aggrname_p (TYPE_IDENTIFIER (t)))
10066 /* We do not rename the debug info representing the
10067 unnamed tagged type because the standard says in
10068 [dcl.typedef] that the naming applies only for
10069 linkage purposes. */
10070 /*debug_hooks->set_name (t, decl);*/
10071 TYPE_NAME (t) = decl;
10072 }
10073
10074 if (TYPE_LANG_SPECIFIC (type))
10075 TYPE_WAS_UNNAMED (type) = 1;
10076
10077 /* If this is a typedef within a template class, the nested
10078 type is a (non-primary) template. The name for the
10079 template needs updating as well. */
10080 if (TYPE_LANG_SPECIFIC (type) && CLASSTYPE_TEMPLATE_INFO (type))
10081 DECL_NAME (CLASSTYPE_TI_TEMPLATE (type))
10082 = TYPE_IDENTIFIER (type);
10083
10084 /* Adjust linkage now that we aren't unnamed anymore. */
10085 reset_type_linkage (type);
10086
10087 /* FIXME remangle member functions; member functions of a
10088 type with external linkage have external linkage. */
10089
10090 /* Check that our job is done, and that it would fail if we
10091 attempted to do it again. */
10092 gcc_assert (!TYPE_UNNAMED_P (type));
10093 }
10094
10095 /* Given declspecs and a declarator (abstract or otherwise), determine
10096 the name and type of the object declared and construct a DECL node
10097 for it.
10098
10099 DECLSPECS points to the representation of declaration-specifier
10100 sequence that precedes declarator.
10101
10102 DECL_CONTEXT says which syntactic context this declaration is in:
10103 NORMAL for most contexts. Make a VAR_DECL or FUNCTION_DECL or TYPE_DECL.
10104 FUNCDEF for a function definition. Like NORMAL but a few different
10105 error messages in each case. Return value may be zero meaning
10106 this definition is too screwy to try to parse.
10107 MEMFUNCDEF for a function definition. Like FUNCDEF but prepares to
10108 handle member functions (which have FIELD context).
10109 Return value may be zero meaning this definition is too screwy to
10110 try to parse.
10111 PARM for a parameter declaration (either within a function prototype
10112 or before a function body). Make a PARM_DECL, or return void_type_node.
10113 TPARM for a template parameter declaration.
10114 CATCHPARM for a parameter declaration before a catch clause.
10115 TYPENAME if for a typename (in a cast or sizeof).
10116 Don't make a DECL node; just return the ..._TYPE node.
10117 FIELD for a struct or union field; make a FIELD_DECL.
10118 BITFIELD for a field with specified width.
10119
10120 INITIALIZED is as for start_decl.
10121
10122 ATTRLIST is a pointer to the list of attributes, which may be NULL
10123 if there are none; *ATTRLIST may be modified if attributes from inside
10124 the declarator should be applied to the declaration.
10125
10126 When this function is called, scoping variables (such as
10127 CURRENT_CLASS_TYPE) should reflect the scope in which the
10128 declaration occurs, not the scope in which the new declaration will
10129 be placed. For example, on:
10130
10131 void S::f() { ... }
10132
10133 when grokdeclarator is called for `S::f', the CURRENT_CLASS_TYPE
10134 should not be `S'.
10135
10136 Returns a DECL (if a declarator is present), a TYPE (if there is no
10137 declarator, in cases like "struct S;"), or the ERROR_MARK_NODE if an
10138 error occurs. */
10139
10140 tree
grokdeclarator(const cp_declarator * declarator,cp_decl_specifier_seq * declspecs,enum decl_context decl_context,int initialized,tree * attrlist)10141 grokdeclarator (const cp_declarator *declarator,
10142 cp_decl_specifier_seq *declspecs,
10143 enum decl_context decl_context,
10144 int initialized,
10145 tree* attrlist)
10146 {
10147 tree type = NULL_TREE;
10148 int longlong = 0;
10149 int explicit_intN = 0;
10150 int virtualp, explicitp, friendp, inlinep, staticp;
10151 int explicit_int = 0;
10152 int explicit_char = 0;
10153 int defaulted_int = 0;
10154
10155 tree typedef_decl = NULL_TREE;
10156 const char *name = NULL;
10157 tree typedef_type = NULL_TREE;
10158 /* True if this declarator is a function definition. */
10159 bool funcdef_flag = false;
10160 cp_declarator_kind innermost_code = cdk_error;
10161 int bitfield = 0;
10162 #if 0
10163 /* See the code below that used this. */
10164 tree decl_attr = NULL_TREE;
10165 #endif
10166
10167 /* Keep track of what sort of function is being processed
10168 so that we can warn about default return values, or explicit
10169 return values which do not match prescribed defaults. */
10170 special_function_kind sfk = sfk_none;
10171
10172 tree dname = NULL_TREE;
10173 tree ctor_return_type = NULL_TREE;
10174 enum overload_flags flags = NO_SPECIAL;
10175 /* cv-qualifiers that apply to the declarator, for a declaration of
10176 a member function. */
10177 cp_cv_quals memfn_quals = TYPE_UNQUALIFIED;
10178 /* virt-specifiers that apply to the declarator, for a declaration of
10179 a member function. */
10180 cp_virt_specifiers virt_specifiers = VIRT_SPEC_UNSPECIFIED;
10181 /* ref-qualifier that applies to the declarator, for a declaration of
10182 a member function. */
10183 cp_ref_qualifier rqual = REF_QUAL_NONE;
10184 /* cv-qualifiers that apply to the type specified by the DECLSPECS. */
10185 int type_quals = TYPE_UNQUALIFIED;
10186 tree raises = NULL_TREE;
10187 int template_count = 0;
10188 tree returned_attrs = NULL_TREE;
10189 tree parms = NULL_TREE;
10190 const cp_declarator *id_declarator;
10191 /* The unqualified name of the declarator; either an
10192 IDENTIFIER_NODE, BIT_NOT_EXPR, or TEMPLATE_ID_EXPR. */
10193 tree unqualified_id;
10194 /* The class type, if any, in which this entity is located,
10195 or NULL_TREE if none. Note that this value may be different from
10196 the current class type; for example if an attempt is made to declare
10197 "A::f" inside "B", this value will be "A". */
10198 tree ctype = current_class_type;
10199 /* The NAMESPACE_DECL for the namespace in which this entity is
10200 located. If an unqualified name is used to declare the entity,
10201 this value will be NULL_TREE, even if the entity is located at
10202 namespace scope. */
10203 tree in_namespace = NULL_TREE;
10204 cp_storage_class storage_class;
10205 bool unsigned_p, signed_p, short_p, long_p, thread_p;
10206 bool type_was_error_mark_node = false;
10207 bool parameter_pack_p = declarator ? declarator->parameter_pack_p : false;
10208 bool template_type_arg = false;
10209 bool template_parm_flag = false;
10210 bool typedef_p = decl_spec_seq_has_spec_p (declspecs, ds_typedef);
10211 bool constexpr_p = decl_spec_seq_has_spec_p (declspecs, ds_constexpr);
10212 bool late_return_type_p = false;
10213 bool array_parameter_p = false;
10214 source_location saved_loc = input_location;
10215 tree reqs = NULL_TREE;
10216
10217 signed_p = decl_spec_seq_has_spec_p (declspecs, ds_signed);
10218 unsigned_p = decl_spec_seq_has_spec_p (declspecs, ds_unsigned);
10219 short_p = decl_spec_seq_has_spec_p (declspecs, ds_short);
10220 long_p = decl_spec_seq_has_spec_p (declspecs, ds_long);
10221 longlong = decl_spec_seq_has_spec_p (declspecs, ds_long_long);
10222 explicit_intN = declspecs->explicit_intN_p;
10223 thread_p = decl_spec_seq_has_spec_p (declspecs, ds_thread);
10224
10225 // Was concept_p specified? Note that ds_concept
10226 // implies ds_constexpr!
10227 bool concept_p = decl_spec_seq_has_spec_p (declspecs, ds_concept);
10228 if (concept_p)
10229 constexpr_p = true;
10230
10231 if (decl_spec_seq_has_spec_p (declspecs, ds_const))
10232 type_quals |= TYPE_QUAL_CONST;
10233 if (decl_spec_seq_has_spec_p (declspecs, ds_volatile))
10234 type_quals |= TYPE_QUAL_VOLATILE;
10235 if (decl_spec_seq_has_spec_p (declspecs, ds_restrict))
10236 type_quals |= TYPE_QUAL_RESTRICT;
10237
10238 if (decl_context == FUNCDEF)
10239 funcdef_flag = true, decl_context = NORMAL;
10240 else if (decl_context == MEMFUNCDEF)
10241 funcdef_flag = true, decl_context = FIELD;
10242 else if (decl_context == BITFIELD)
10243 bitfield = 1, decl_context = FIELD;
10244 else if (decl_context == TEMPLATE_TYPE_ARG)
10245 template_type_arg = true, decl_context = TYPENAME;
10246 else if (decl_context == TPARM)
10247 template_parm_flag = true, decl_context = PARM;
10248
10249 if (initialized > 1)
10250 funcdef_flag = true;
10251
10252 location_t typespec_loc = smallest_type_quals_location (type_quals,
10253 declspecs->locations);
10254 if (typespec_loc == UNKNOWN_LOCATION)
10255 typespec_loc = declspecs->locations[ds_type_spec];
10256 if (typespec_loc == UNKNOWN_LOCATION)
10257 typespec_loc = input_location;
10258
10259 /* Look inside a declarator for the name being declared
10260 and get it as a string, for an error message. */
10261 for (id_declarator = declarator;
10262 id_declarator;
10263 id_declarator = id_declarator->declarator)
10264 {
10265 if (id_declarator->kind != cdk_id)
10266 innermost_code = id_declarator->kind;
10267
10268 switch (id_declarator->kind)
10269 {
10270 case cdk_function:
10271 if (id_declarator->declarator
10272 && id_declarator->declarator->kind == cdk_id)
10273 {
10274 sfk = id_declarator->declarator->u.id.sfk;
10275 if (sfk == sfk_destructor)
10276 flags = DTOR_FLAG;
10277 }
10278 break;
10279
10280 case cdk_id:
10281 {
10282 tree qualifying_scope = id_declarator->u.id.qualifying_scope;
10283 tree decl = id_declarator->u.id.unqualified_name;
10284 if (!decl)
10285 break;
10286 if (qualifying_scope)
10287 {
10288 if (check_for_bare_parameter_packs (qualifying_scope,
10289 id_declarator->id_loc))
10290 return error_mark_node;
10291 if (at_function_scope_p ())
10292 {
10293 /* [dcl.meaning]
10294
10295 A declarator-id shall not be qualified except
10296 for ...
10297
10298 None of the cases are permitted in block
10299 scope. */
10300 if (qualifying_scope == global_namespace)
10301 error ("invalid use of qualified-name %<::%D%>",
10302 decl);
10303 else if (TYPE_P (qualifying_scope))
10304 error ("invalid use of qualified-name %<%T::%D%>",
10305 qualifying_scope, decl);
10306 else
10307 error ("invalid use of qualified-name %<%D::%D%>",
10308 qualifying_scope, decl);
10309 return error_mark_node;
10310 }
10311 else if (TYPE_P (qualifying_scope))
10312 {
10313 ctype = qualifying_scope;
10314 if (!MAYBE_CLASS_TYPE_P (ctype))
10315 {
10316 error ("%q#T is not a class or a namespace", ctype);
10317 ctype = NULL_TREE;
10318 }
10319 else if (innermost_code != cdk_function
10320 && current_class_type
10321 && !uniquely_derived_from_p (ctype,
10322 current_class_type))
10323 {
10324 error ("invalid use of qualified-name %<%T::%D%>",
10325 qualifying_scope, decl);
10326 return error_mark_node;
10327 }
10328 }
10329 else if (TREE_CODE (qualifying_scope) == NAMESPACE_DECL)
10330 in_namespace = qualifying_scope;
10331 }
10332 switch (TREE_CODE (decl))
10333 {
10334 case BIT_NOT_EXPR:
10335 {
10336 if (innermost_code != cdk_function)
10337 {
10338 error ("declaration of %qD as non-function", decl);
10339 return error_mark_node;
10340 }
10341 else if (!qualifying_scope
10342 && !(current_class_type && at_class_scope_p ()))
10343 {
10344 error ("declaration of %qD as non-member", decl);
10345 return error_mark_node;
10346 }
10347
10348 tree type = TREE_OPERAND (decl, 0);
10349 if (TYPE_P (type))
10350 type = constructor_name (type);
10351 name = identifier_to_locale (IDENTIFIER_POINTER (type));
10352 dname = decl;
10353 }
10354 break;
10355
10356 case TEMPLATE_ID_EXPR:
10357 {
10358 tree fns = TREE_OPERAND (decl, 0);
10359
10360 dname = fns;
10361 if (!identifier_p (dname))
10362 dname = OVL_NAME (dname);
10363 }
10364 /* Fall through. */
10365
10366 case IDENTIFIER_NODE:
10367 if (identifier_p (decl))
10368 dname = decl;
10369
10370 if (IDENTIFIER_KEYWORD_P (dname))
10371 {
10372 error ("declarator-id missing; using reserved word %qD",
10373 dname);
10374 name = identifier_to_locale (IDENTIFIER_POINTER (dname));
10375 }
10376 else if (!IDENTIFIER_CONV_OP_P (dname))
10377 name = identifier_to_locale (IDENTIFIER_POINTER (dname));
10378 else
10379 {
10380 gcc_assert (flags == NO_SPECIAL);
10381 flags = TYPENAME_FLAG;
10382 sfk = sfk_conversion;
10383 tree glob = get_global_binding (dname);
10384 if (glob && TREE_CODE (glob) == TYPE_DECL)
10385 name = identifier_to_locale (IDENTIFIER_POINTER (dname));
10386 else
10387 name = "<invalid operator>";
10388 }
10389 break;
10390
10391 default:
10392 gcc_unreachable ();
10393 }
10394 break;
10395 }
10396
10397 case cdk_array:
10398 case cdk_pointer:
10399 case cdk_reference:
10400 case cdk_ptrmem:
10401 break;
10402
10403 case cdk_decomp:
10404 name = "structured binding";
10405 break;
10406
10407 case cdk_error:
10408 return error_mark_node;
10409
10410 default:
10411 gcc_unreachable ();
10412 }
10413 if (id_declarator->kind == cdk_id)
10414 break;
10415 }
10416
10417 /* [dcl.fct.edf]
10418
10419 The declarator in a function-definition shall have the form
10420 D1 ( parameter-declaration-clause) ... */
10421 if (funcdef_flag && innermost_code != cdk_function)
10422 {
10423 error ("function definition does not declare parameters");
10424 return error_mark_node;
10425 }
10426
10427 if (flags == TYPENAME_FLAG
10428 && innermost_code != cdk_function
10429 && ! (ctype && !declspecs->any_specifiers_p))
10430 {
10431 error ("declaration of %qD as non-function", dname);
10432 return error_mark_node;
10433 }
10434
10435 if (dname && identifier_p (dname))
10436 {
10437 if (UDLIT_OPER_P (dname)
10438 && innermost_code != cdk_function)
10439 {
10440 error ("declaration of %qD as non-function", dname);
10441 return error_mark_node;
10442 }
10443
10444 if (IDENTIFIER_ANY_OP_P (dname))
10445 {
10446 if (typedef_p)
10447 {
10448 error ("declaration of %qD as %<typedef%>", dname);
10449 return error_mark_node;
10450 }
10451 else if (decl_context == PARM || decl_context == CATCHPARM)
10452 {
10453 error ("declaration of %qD as parameter", dname);
10454 return error_mark_node;
10455 }
10456 }
10457 }
10458
10459 /* Anything declared one level down from the top level
10460 must be one of the parameters of a function
10461 (because the body is at least two levels down). */
10462
10463 /* This heuristic cannot be applied to C++ nodes! Fixed, however,
10464 by not allowing C++ class definitions to specify their parameters
10465 with xdecls (must be spec.d in the parmlist).
10466
10467 Since we now wait to push a class scope until we are sure that
10468 we are in a legitimate method context, we must set oldcname
10469 explicitly (since current_class_name is not yet alive).
10470
10471 We also want to avoid calling this a PARM if it is in a namespace. */
10472
10473 if (decl_context == NORMAL && !toplevel_bindings_p ())
10474 {
10475 cp_binding_level *b = current_binding_level;
10476 current_binding_level = b->level_chain;
10477 if (current_binding_level != 0 && toplevel_bindings_p ())
10478 decl_context = PARM;
10479 current_binding_level = b;
10480 }
10481
10482 if (name == NULL)
10483 name = decl_context == PARM ? "parameter" : "type name";
10484
10485 if (concept_p && typedef_p)
10486 {
10487 error ("%<concept%> cannot appear in a typedef declaration");
10488 return error_mark_node;
10489 }
10490
10491 if (constexpr_p && typedef_p)
10492 {
10493 error ("%<constexpr%> cannot appear in a typedef declaration");
10494 return error_mark_node;
10495 }
10496
10497 /* If there were multiple types specified in the decl-specifier-seq,
10498 issue an error message. */
10499 if (declspecs->multiple_types_p)
10500 {
10501 error ("two or more data types in declaration of %qs", name);
10502 return error_mark_node;
10503 }
10504
10505 if (declspecs->conflicting_specifiers_p)
10506 {
10507 error ("conflicting specifiers in declaration of %qs", name);
10508 return error_mark_node;
10509 }
10510
10511 /* Extract the basic type from the decl-specifier-seq. */
10512 type = declspecs->type;
10513 if (type == error_mark_node)
10514 {
10515 type = NULL_TREE;
10516 type_was_error_mark_node = true;
10517 }
10518 /* If the entire declaration is itself tagged as deprecated then
10519 suppress reports of deprecated items. */
10520 if (type && TREE_DEPRECATED (type)
10521 && deprecated_state != DEPRECATED_SUPPRESS)
10522 cp_warn_deprecated_use (type);
10523 if (type && TREE_CODE (type) == TYPE_DECL)
10524 {
10525 typedef_decl = type;
10526 type = TREE_TYPE (typedef_decl);
10527 if (TREE_DEPRECATED (type)
10528 && DECL_ARTIFICIAL (typedef_decl)
10529 && deprecated_state != DEPRECATED_SUPPRESS)
10530 cp_warn_deprecated_use (type);
10531 }
10532 /* No type at all: default to `int', and set DEFAULTED_INT
10533 because it was not a user-defined typedef. */
10534 if (type == NULL_TREE)
10535 {
10536 if (signed_p || unsigned_p || long_p || short_p)
10537 {
10538 /* These imply 'int'. */
10539 type = integer_type_node;
10540 defaulted_int = 1;
10541 }
10542 /* If we just have "complex", it is equivalent to "complex double". */
10543 else if (!longlong && !explicit_intN
10544 && decl_spec_seq_has_spec_p (declspecs, ds_complex))
10545 {
10546 type = double_type_node;
10547 pedwarn (declspecs->locations[ds_complex], OPT_Wpedantic,
10548 "ISO C++ does not support plain %<complex%> meaning "
10549 "%<double complex%>");
10550 }
10551 }
10552 /* Gather flags. */
10553 explicit_int = declspecs->explicit_int_p;
10554 explicit_char = declspecs->explicit_char_p;
10555
10556 #if 0
10557 /* See the code below that used this. */
10558 if (typedef_decl)
10559 decl_attr = DECL_ATTRIBUTES (typedef_decl);
10560 #endif
10561 typedef_type = type;
10562
10563 if (sfk == sfk_conversion || sfk == sfk_deduction_guide)
10564 ctor_return_type = TREE_TYPE (dname);
10565 else
10566 ctor_return_type = ctype;
10567
10568 if (sfk != sfk_none)
10569 {
10570 type = check_special_function_return_type (sfk, type,
10571 ctor_return_type,
10572 type_quals,
10573 declspecs->locations);
10574 type_quals = TYPE_UNQUALIFIED;
10575 }
10576 else if (type == NULL_TREE)
10577 {
10578 int is_main;
10579
10580 explicit_int = -1;
10581
10582 /* We handle `main' specially here, because 'main () { }' is so
10583 common. With no options, it is allowed. With -Wreturn-type,
10584 it is a warning. It is only an error with -pedantic-errors. */
10585 is_main = (funcdef_flag
10586 && dname && identifier_p (dname)
10587 && MAIN_NAME_P (dname)
10588 && ctype == NULL_TREE
10589 && in_namespace == NULL_TREE
10590 && current_namespace == global_namespace);
10591
10592 if (type_was_error_mark_node)
10593 /* We've already issued an error, don't complain more. */;
10594 else if (in_system_header_at (input_location) || flag_ms_extensions)
10595 /* Allow it, sigh. */;
10596 else if (! is_main)
10597 permerror (input_location, "ISO C++ forbids declaration of %qs with no type", name);
10598 else if (pedantic)
10599 pedwarn (input_location, OPT_Wpedantic,
10600 "ISO C++ forbids declaration of %qs with no type", name);
10601 else
10602 warning (OPT_Wreturn_type,
10603 "ISO C++ forbids declaration of %qs with no type", name);
10604
10605 if (type_was_error_mark_node && template_parm_flag)
10606 /* FIXME we should be able to propagate the error_mark_node as is
10607 for other contexts too. */
10608 type = error_mark_node;
10609 else
10610 type = integer_type_node;
10611 }
10612
10613 ctype = NULL_TREE;
10614
10615 if (explicit_intN)
10616 {
10617 if (! int_n_enabled_p[declspecs->int_n_idx])
10618 {
10619 error ("%<__int%d%> is not supported by this target",
10620 int_n_data[declspecs->int_n_idx].bitsize);
10621 explicit_intN = false;
10622 }
10623 else if (pedantic && ! in_system_header_at (input_location))
10624 pedwarn (input_location, OPT_Wpedantic,
10625 "ISO C++ does not support %<__int%d%> for %qs",
10626 int_n_data[declspecs->int_n_idx].bitsize, name);
10627 }
10628
10629 /* Now process the modifiers that were specified
10630 and check for invalid combinations. */
10631
10632 /* Long double is a special combination. */
10633 if (long_p && !longlong && TYPE_MAIN_VARIANT (type) == double_type_node)
10634 {
10635 long_p = false;
10636 type = cp_build_qualified_type (long_double_type_node,
10637 cp_type_quals (type));
10638 }
10639
10640 /* Check all other uses of type modifiers. */
10641
10642 if (unsigned_p || signed_p || long_p || short_p)
10643 {
10644 int ok = 0;
10645
10646 if ((signed_p || unsigned_p) && TREE_CODE (type) != INTEGER_TYPE)
10647 error ("%<signed%> or %<unsigned%> invalid for %qs", name);
10648 else if (signed_p && unsigned_p)
10649 error ("%<signed%> and %<unsigned%> specified together for %qs", name);
10650 else if (longlong && TREE_CODE (type) != INTEGER_TYPE)
10651 error ("%<long long%> invalid for %qs", name);
10652 else if (long_p && TREE_CODE (type) == REAL_TYPE)
10653 error ("%<long%> invalid for %qs", name);
10654 else if (short_p && TREE_CODE (type) == REAL_TYPE)
10655 error ("%<short%> invalid for %qs", name);
10656 else if ((long_p || short_p) && TREE_CODE (type) != INTEGER_TYPE)
10657 error ("%<long%> or %<short%> invalid for %qs", name);
10658 else if ((long_p || short_p || explicit_char || explicit_int) && explicit_intN)
10659 error ("%<long%>, %<int%>, %<short%>, or %<char%> invalid for %qs", name);
10660 else if ((long_p || short_p) && explicit_char)
10661 error ("%<long%> or %<short%> specified with char for %qs", name);
10662 else if (long_p && short_p)
10663 error ("%<long%> and %<short%> specified together for %qs", name);
10664 else if (type == char16_type_node || type == char32_type_node)
10665 {
10666 if (signed_p || unsigned_p)
10667 error ("%<signed%> or %<unsigned%> invalid for %qs", name);
10668 else if (short_p || long_p)
10669 error ("%<short%> or %<long%> invalid for %qs", name);
10670 }
10671 else
10672 {
10673 ok = 1;
10674 if (!explicit_int && !defaulted_int && !explicit_char && !explicit_intN && pedantic)
10675 {
10676 pedwarn (input_location, OPT_Wpedantic,
10677 "long, short, signed or unsigned used invalidly for %qs",
10678 name);
10679 if (flag_pedantic_errors)
10680 ok = 0;
10681 }
10682 }
10683
10684 /* Discard the type modifiers if they are invalid. */
10685 if (! ok)
10686 {
10687 unsigned_p = false;
10688 signed_p = false;
10689 long_p = false;
10690 short_p = false;
10691 longlong = 0;
10692 }
10693 }
10694
10695 /* Decide whether an integer type is signed or not.
10696 Optionally treat bitfields as signed by default. */
10697 if (unsigned_p
10698 /* [class.bit]
10699
10700 It is implementation-defined whether a plain (neither
10701 explicitly signed or unsigned) char, short, int, or long
10702 bit-field is signed or unsigned.
10703
10704 Naturally, we extend this to long long as well. Note that
10705 this does not include wchar_t. */
10706 || (bitfield && !flag_signed_bitfields
10707 && !signed_p
10708 /* A typedef for plain `int' without `signed' can be
10709 controlled just like plain `int', but a typedef for
10710 `signed int' cannot be so controlled. */
10711 && !(typedef_decl
10712 && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl))
10713 && TREE_CODE (type) == INTEGER_TYPE
10714 && !same_type_p (TYPE_MAIN_VARIANT (type), wchar_type_node)))
10715 {
10716 if (explicit_intN)
10717 type = int_n_trees[declspecs->int_n_idx].unsigned_type;
10718 else if (longlong)
10719 type = long_long_unsigned_type_node;
10720 else if (long_p)
10721 type = long_unsigned_type_node;
10722 else if (short_p)
10723 type = short_unsigned_type_node;
10724 else if (type == char_type_node)
10725 type = unsigned_char_type_node;
10726 else if (typedef_decl)
10727 type = unsigned_type_for (type);
10728 else
10729 type = unsigned_type_node;
10730 }
10731 else if (signed_p && type == char_type_node)
10732 type = signed_char_type_node;
10733 else if (explicit_intN)
10734 type = int_n_trees[declspecs->int_n_idx].signed_type;
10735 else if (longlong)
10736 type = long_long_integer_type_node;
10737 else if (long_p)
10738 type = long_integer_type_node;
10739 else if (short_p)
10740 type = short_integer_type_node;
10741
10742 if (decl_spec_seq_has_spec_p (declspecs, ds_complex))
10743 {
10744 if (TREE_CODE (type) != INTEGER_TYPE && TREE_CODE (type) != REAL_TYPE)
10745 error ("complex invalid for %qs", name);
10746 /* If a modifier is specified, the resulting complex is the complex
10747 form of TYPE. E.g, "complex short" is "complex short int". */
10748 else if (type == integer_type_node)
10749 type = complex_integer_type_node;
10750 else if (type == float_type_node)
10751 type = complex_float_type_node;
10752 else if (type == double_type_node)
10753 type = complex_double_type_node;
10754 else if (type == long_double_type_node)
10755 type = complex_long_double_type_node;
10756 else
10757 type = build_complex_type (type);
10758 }
10759
10760 /* If we're using the injected-class-name to form a compound type or a
10761 declaration, replace it with the underlying class so we don't get
10762 redundant typedefs in the debug output. But if we are returning the
10763 type unchanged, leave it alone so that it's available to
10764 maybe_get_template_decl_from_type_decl. */
10765 if (CLASS_TYPE_P (type)
10766 && DECL_SELF_REFERENCE_P (TYPE_NAME (type))
10767 && type == TREE_TYPE (TYPE_NAME (type))
10768 && (declarator || type_quals))
10769 type = DECL_ORIGINAL_TYPE (TYPE_NAME (type));
10770
10771 type_quals |= cp_type_quals (type);
10772 type = cp_build_qualified_type_real
10773 (type, type_quals, ((((typedef_decl && !DECL_ARTIFICIAL (typedef_decl))
10774 || declspecs->decltype_p)
10775 ? tf_ignore_bad_quals : 0) | tf_warning_or_error));
10776 /* We might have ignored or rejected some of the qualifiers. */
10777 type_quals = cp_type_quals (type);
10778
10779 if (cxx_dialect >= cxx17 && type && is_auto (type)
10780 && innermost_code != cdk_function
10781 && id_declarator && declarator != id_declarator)
10782 if (tree tmpl = CLASS_PLACEHOLDER_TEMPLATE (type))
10783 {
10784 error_at (typespec_loc, "template placeholder type %qT must be followed "
10785 "by a simple declarator-id", type);
10786 inform (DECL_SOURCE_LOCATION (tmpl), "%qD declared here", tmpl);
10787 }
10788
10789 staticp = 0;
10790 inlinep = decl_spec_seq_has_spec_p (declspecs, ds_inline);
10791 virtualp = decl_spec_seq_has_spec_p (declspecs, ds_virtual);
10792 explicitp = decl_spec_seq_has_spec_p (declspecs, ds_explicit);
10793
10794 storage_class = declspecs->storage_class;
10795 if (storage_class == sc_static)
10796 staticp = 1 + (decl_context == FIELD);
10797
10798 if (virtualp)
10799 {
10800 if (staticp == 2)
10801 {
10802 error ("member %qD cannot be declared both %<virtual%> "
10803 "and %<static%>", dname);
10804 storage_class = sc_none;
10805 staticp = 0;
10806 }
10807 if (constexpr_p)
10808 error ("member %qD cannot be declared both %<virtual%> "
10809 "and %<constexpr%>", dname);
10810 }
10811 friendp = decl_spec_seq_has_spec_p (declspecs, ds_friend);
10812
10813 /* Issue errors about use of storage classes for parameters. */
10814 if (decl_context == PARM)
10815 {
10816 if (typedef_p)
10817 {
10818 error ("typedef declaration invalid in parameter declaration");
10819 return error_mark_node;
10820 }
10821 else if (template_parm_flag && storage_class != sc_none)
10822 {
10823 error ("storage class specified for template parameter %qs", name);
10824 return error_mark_node;
10825 }
10826 else if (storage_class == sc_static
10827 || storage_class == sc_extern
10828 || thread_p)
10829 error ("storage class specifiers invalid in parameter declarations");
10830
10831 /* Function parameters cannot be concept. */
10832 if (concept_p)
10833 error ("a parameter cannot be declared %<concept%>");
10834 /* Function parameters cannot be constexpr. If we saw one, moan
10835 and pretend it wasn't there. */
10836 else if (constexpr_p)
10837 {
10838 error ("a parameter cannot be declared %<constexpr%>");
10839 constexpr_p = 0;
10840 }
10841 }
10842
10843 /* Give error if `virtual' is used outside of class declaration. */
10844 if (virtualp
10845 && (current_class_name == NULL_TREE || decl_context != FIELD))
10846 {
10847 error_at (declspecs->locations[ds_virtual],
10848 "%<virtual%> outside class declaration");
10849 virtualp = 0;
10850 }
10851
10852 if (innermost_code == cdk_decomp)
10853 {
10854 location_t loc = (declarator->kind == cdk_reference
10855 ? declarator->declarator->id_loc : declarator->id_loc);
10856 if (inlinep)
10857 error_at (declspecs->locations[ds_inline],
10858 "structured binding declaration cannot be %<inline%>");
10859 if (typedef_p)
10860 error_at (declspecs->locations[ds_typedef],
10861 "structured binding declaration cannot be %<typedef%>");
10862 if (constexpr_p)
10863 error_at (declspecs->locations[ds_constexpr], "structured "
10864 "binding declaration cannot be %<constexpr%>");
10865 if (thread_p)
10866 error_at (declspecs->locations[ds_thread],
10867 "structured binding declaration cannot be %qs",
10868 declspecs->gnu_thread_keyword_p
10869 ? "__thread" : "thread_local");
10870 if (concept_p)
10871 error_at (declspecs->locations[ds_concept],
10872 "structured binding declaration cannot be %<concept%>");
10873 switch (storage_class)
10874 {
10875 case sc_none:
10876 break;
10877 case sc_register:
10878 error_at (loc, "structured binding declaration cannot be "
10879 "%<register%>");
10880 break;
10881 case sc_static:
10882 error_at (loc, "structured binding declaration cannot be "
10883 "%<static%>");
10884 break;
10885 case sc_extern:
10886 error_at (loc, "structured binding declaration cannot be "
10887 "%<extern%>");
10888 break;
10889 case sc_mutable:
10890 error_at (loc, "structured binding declaration cannot be "
10891 "%<mutable%>");
10892 break;
10893 case sc_auto:
10894 error_at (loc, "structured binding declaration cannot be "
10895 "C++98 %<auto%>");
10896 break;
10897 default:
10898 gcc_unreachable ();
10899 }
10900 if (TREE_CODE (type) != TEMPLATE_TYPE_PARM
10901 || TYPE_IDENTIFIER (type) != auto_identifier)
10902 {
10903 if (type != error_mark_node)
10904 {
10905 error_at (loc, "structured binding declaration cannot have "
10906 "type %qT", type);
10907 inform (loc,
10908 "type must be cv-qualified %<auto%> or reference to "
10909 "cv-qualified %<auto%>");
10910 }
10911 type = build_qualified_type (make_auto (), type_quals);
10912 declspecs->type = type;
10913 }
10914 inlinep = 0;
10915 typedef_p = 0;
10916 constexpr_p = 0;
10917 thread_p = 0;
10918 concept_p = 0;
10919 storage_class = sc_none;
10920 staticp = 0;
10921 declspecs->storage_class = sc_none;
10922 declspecs->locations[ds_thread] = UNKNOWN_LOCATION;
10923 }
10924
10925 /* Static anonymous unions are dealt with here. */
10926 if (staticp && decl_context == TYPENAME
10927 && declspecs->type
10928 && ANON_AGGR_TYPE_P (declspecs->type))
10929 decl_context = FIELD;
10930
10931 /* Warn about storage classes that are invalid for certain
10932 kinds of declarations (parameters, typenames, etc.). */
10933 if (thread_p
10934 && ((storage_class
10935 && storage_class != sc_extern
10936 && storage_class != sc_static)
10937 || typedef_p))
10938 {
10939 error ("multiple storage classes in declaration of %qs", name);
10940 thread_p = false;
10941 }
10942 if (decl_context != NORMAL
10943 && ((storage_class != sc_none
10944 && storage_class != sc_mutable)
10945 || thread_p))
10946 {
10947 if ((decl_context == PARM || decl_context == CATCHPARM)
10948 && (storage_class == sc_register
10949 || storage_class == sc_auto))
10950 ;
10951 else if (typedef_p)
10952 ;
10953 else if (decl_context == FIELD
10954 /* C++ allows static class elements. */
10955 && storage_class == sc_static)
10956 /* C++ also allows inlines and signed and unsigned elements,
10957 but in those cases we don't come in here. */
10958 ;
10959 else
10960 {
10961 if (decl_context == FIELD)
10962 error ("storage class specified for %qs", name);
10963 else
10964 {
10965 if (decl_context == PARM || decl_context == CATCHPARM)
10966 error ("storage class specified for parameter %qs", name);
10967 else
10968 error ("storage class specified for typename");
10969 }
10970 if (storage_class == sc_register
10971 || storage_class == sc_auto
10972 || storage_class == sc_extern
10973 || thread_p)
10974 storage_class = sc_none;
10975 }
10976 }
10977 else if (storage_class == sc_extern && funcdef_flag
10978 && ! toplevel_bindings_p ())
10979 error ("nested function %qs declared %<extern%>", name);
10980 else if (toplevel_bindings_p ())
10981 {
10982 if (storage_class == sc_auto)
10983 error ("top-level declaration of %qs specifies %<auto%>", name);
10984 }
10985 else if (thread_p
10986 && storage_class != sc_extern
10987 && storage_class != sc_static)
10988 {
10989 if (declspecs->gnu_thread_keyword_p)
10990 pedwarn (input_location, 0, "function-scope %qs implicitly auto and "
10991 "declared %<__thread%>", name);
10992
10993 /* When thread_local is applied to a variable of block scope the
10994 storage-class-specifier static is implied if it does not appear
10995 explicitly. */
10996 storage_class = declspecs->storage_class = sc_static;
10997 staticp = 1;
10998 }
10999
11000 if (storage_class && friendp)
11001 {
11002 error ("storage class specifiers invalid in friend function declarations");
11003 storage_class = sc_none;
11004 staticp = 0;
11005 }
11006
11007 if (!id_declarator)
11008 unqualified_id = NULL_TREE;
11009 else
11010 {
11011 unqualified_id = id_declarator->u.id.unqualified_name;
11012 switch (TREE_CODE (unqualified_id))
11013 {
11014 case BIT_NOT_EXPR:
11015 unqualified_id = TREE_OPERAND (unqualified_id, 0);
11016 if (TYPE_P (unqualified_id))
11017 unqualified_id = constructor_name (unqualified_id);
11018 break;
11019
11020 case IDENTIFIER_NODE:
11021 case TEMPLATE_ID_EXPR:
11022 break;
11023
11024 default:
11025 gcc_unreachable ();
11026 }
11027 }
11028
11029 if (declspecs->std_attributes)
11030 {
11031 location_t attr_loc = declspecs->locations[ds_std_attribute];
11032 if (warning_at (attr_loc, OPT_Wattributes, "attribute ignored"))
11033 inform (attr_loc, "an attribute that appertains to a type-specifier "
11034 "is ignored");
11035 }
11036
11037 /* Determine the type of the entity declared by recurring on the
11038 declarator. */
11039 for (; declarator; declarator = declarator->declarator)
11040 {
11041 const cp_declarator *inner_declarator;
11042 tree attrs;
11043
11044 if (type == error_mark_node)
11045 return error_mark_node;
11046
11047 attrs = declarator->attributes;
11048 if (attrs)
11049 {
11050 int attr_flags;
11051
11052 attr_flags = 0;
11053 if (declarator == NULL || declarator->kind == cdk_id)
11054 attr_flags |= (int) ATTR_FLAG_DECL_NEXT;
11055 if (declarator->kind == cdk_function)
11056 attr_flags |= (int) ATTR_FLAG_FUNCTION_NEXT;
11057 if (declarator->kind == cdk_array)
11058 attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT;
11059 returned_attrs = decl_attributes (&type,
11060 chainon (returned_attrs, attrs),
11061 attr_flags);
11062 }
11063
11064 inner_declarator = declarator->declarator;
11065
11066 /* We don't want to warn in parameter context because we don't
11067 yet know if the parse will succeed, and this might turn out
11068 to be a constructor call. */
11069 if (decl_context != PARM
11070 && decl_context != TYPENAME
11071 && !typedef_p
11072 && declarator->parenthesized != UNKNOWN_LOCATION
11073 /* If the type is class-like and the inner name used a
11074 global namespace qualifier, we need the parens.
11075 Unfortunately all we can tell is whether a qualified name
11076 was used or not. */
11077 && !(inner_declarator
11078 && inner_declarator->kind == cdk_id
11079 && inner_declarator->u.id.qualifying_scope
11080 && (MAYBE_CLASS_TYPE_P (type)
11081 || TREE_CODE (type) == ENUMERAL_TYPE)))
11082 warning_at (declarator->parenthesized, OPT_Wparentheses,
11083 "unnecessary parentheses in declaration of %qs", name);
11084 if (declarator->kind == cdk_id || declarator->kind == cdk_decomp)
11085 break;
11086
11087 switch (declarator->kind)
11088 {
11089 case cdk_array:
11090 type = create_array_type_for_decl (dname, type,
11091 declarator->u.array.bounds);
11092 if (!valid_array_size_p (input_location, type, dname))
11093 type = error_mark_node;
11094
11095 if (declarator->std_attributes)
11096 /* [dcl.array]/1:
11097
11098 The optional attribute-specifier-seq appertains to the
11099 array. */
11100 returned_attrs = chainon (returned_attrs,
11101 declarator->std_attributes);
11102 break;
11103
11104 case cdk_function:
11105 {
11106 tree arg_types;
11107 int funcdecl_p;
11108
11109 /* Declaring a function type. */
11110
11111 input_location = declspecs->locations[ds_type_spec];
11112 abstract_virtuals_error (ACU_RETURN, type);
11113 input_location = saved_loc;
11114
11115 /* Pick up type qualifiers which should be applied to `this'. */
11116 memfn_quals = declarator->u.function.qualifiers;
11117 /* Pick up virt-specifiers. */
11118 virt_specifiers = declarator->u.function.virt_specifiers;
11119 /* And ref-qualifier, too */
11120 rqual = declarator->u.function.ref_qualifier;
11121 /* And tx-qualifier. */
11122 tree tx_qual = declarator->u.function.tx_qualifier;
11123 /* Pick up the exception specifications. */
11124 raises = declarator->u.function.exception_specification;
11125 /* If the exception-specification is ill-formed, let's pretend
11126 there wasn't one. */
11127 if (raises == error_mark_node)
11128 raises = NULL_TREE;
11129
11130 if (reqs)
11131 error_at (location_of (reqs), "requires-clause on return type");
11132 reqs = declarator->u.function.requires_clause;
11133
11134 /* Say it's a definition only for the CALL_EXPR
11135 closest to the identifier. */
11136 funcdecl_p = inner_declarator && inner_declarator->kind == cdk_id;
11137
11138 /* Handle a late-specified return type. */
11139 tree late_return_type = declarator->u.function.late_return_type;
11140 if (funcdecl_p)
11141 {
11142 if (tree auto_node = type_uses_auto (type))
11143 {
11144 if (!late_return_type)
11145 {
11146 if (current_class_type
11147 && LAMBDA_TYPE_P (current_class_type))
11148 /* OK for C++11 lambdas. */;
11149 else if (cxx_dialect < cxx14)
11150 {
11151 error ("%qs function uses "
11152 "%<auto%> type specifier without trailing "
11153 "return type", name);
11154 inform (input_location, "deduced return type "
11155 "only available with -std=c++14 or "
11156 "-std=gnu++14");
11157 }
11158 else if (virtualp)
11159 {
11160 error ("virtual function cannot "
11161 "have deduced return type");
11162 virtualp = false;
11163 }
11164 }
11165 else if (!is_auto (type) && sfk != sfk_conversion)
11166 {
11167 error ("%qs function with trailing return type has"
11168 " %qT as its type rather than plain %<auto%>",
11169 name, type);
11170 return error_mark_node;
11171 }
11172 tree tmpl = CLASS_PLACEHOLDER_TEMPLATE (auto_node);
11173 if (!tmpl)
11174 if (tree late_auto = type_uses_auto (late_return_type))
11175 tmpl = CLASS_PLACEHOLDER_TEMPLATE (late_auto);
11176 if (tmpl)
11177 {
11178 if (!dguide_name_p (unqualified_id))
11179 {
11180 error_at (declarator->id_loc, "deduced class "
11181 "type %qD in function return type",
11182 DECL_NAME (tmpl));
11183 inform (DECL_SOURCE_LOCATION (tmpl),
11184 "%qD declared here", tmpl);
11185 return error_mark_node;
11186 }
11187 else if (!late_return_type)
11188 {
11189 error_at (declarator->id_loc, "deduction guide "
11190 "for %qT must have trailing return "
11191 "type", TREE_TYPE (tmpl));
11192 inform (DECL_SOURCE_LOCATION (tmpl),
11193 "%qD declared here", tmpl);
11194 return error_mark_node;
11195 }
11196 else if (CLASS_TYPE_P (late_return_type)
11197 && CLASSTYPE_TEMPLATE_INFO (late_return_type)
11198 && (CLASSTYPE_TI_TEMPLATE (late_return_type)
11199 == tmpl))
11200 /* OK */;
11201 else
11202 error ("trailing return type %qT of deduction guide "
11203 "is not a specialization of %qT",
11204 late_return_type, TREE_TYPE (tmpl));
11205 }
11206 }
11207 else if (late_return_type
11208 && sfk != sfk_conversion)
11209 {
11210 if (cxx_dialect < cxx11)
11211 /* Not using maybe_warn_cpp0x because this should
11212 always be an error. */
11213 error ("trailing return type only available with "
11214 "-std=c++11 or -std=gnu++11");
11215 else
11216 error ("%qs function with trailing return type not "
11217 "declared with %<auto%> type specifier", name);
11218 return error_mark_node;
11219 }
11220 }
11221 type = splice_late_return_type (type, late_return_type);
11222 if (type == error_mark_node)
11223 return error_mark_node;
11224
11225 if (late_return_type)
11226 {
11227 late_return_type_p = true;
11228 type_quals = cp_type_quals (type);
11229 }
11230
11231 if (type_quals != TYPE_UNQUALIFIED)
11232 {
11233 if (SCALAR_TYPE_P (type) || VOID_TYPE_P (type))
11234 warning_at (typespec_loc, OPT_Wignored_qualifiers, "type "
11235 "qualifiers ignored on function return type");
11236 /* We now know that the TYPE_QUALS don't apply to the
11237 decl, but to its return type. */
11238 type_quals = TYPE_UNQUALIFIED;
11239 }
11240
11241 /* Error about some types functions can't return. */
11242
11243 if (TREE_CODE (type) == FUNCTION_TYPE)
11244 {
11245 error_at (typespec_loc, "%qs declared as function returning "
11246 "a function", name);
11247 return error_mark_node;
11248 }
11249 if (TREE_CODE (type) == ARRAY_TYPE)
11250 {
11251 error_at (typespec_loc, "%qs declared as function returning "
11252 "an array", name);
11253 return error_mark_node;
11254 }
11255
11256 if (ctype == NULL_TREE
11257 && decl_context == FIELD
11258 && funcdecl_p
11259 && friendp == 0)
11260 ctype = current_class_type;
11261
11262 if (ctype && (sfk == sfk_constructor
11263 || sfk == sfk_destructor))
11264 {
11265 /* We are within a class's scope. If our declarator name
11266 is the same as the class name, and we are defining
11267 a function, then it is a constructor/destructor, and
11268 therefore returns a void type. */
11269
11270 /* ISO C++ 12.4/2. A destructor may not be declared
11271 const or volatile. A destructor may not be static.
11272 A destructor may not be declared with ref-qualifier.
11273
11274 ISO C++ 12.1. A constructor may not be declared
11275 const or volatile. A constructor may not be
11276 virtual. A constructor may not be static.
11277 A constructor may not be declared with ref-qualifier. */
11278 if (staticp == 2)
11279 error ((flags == DTOR_FLAG)
11280 ? G_("destructor cannot be static member function")
11281 : G_("constructor cannot be static member function"));
11282 if (memfn_quals)
11283 {
11284 error ((flags == DTOR_FLAG)
11285 ? G_("destructors may not be cv-qualified")
11286 : G_("constructors may not be cv-qualified"));
11287 memfn_quals = TYPE_UNQUALIFIED;
11288 }
11289
11290 if (rqual)
11291 {
11292 maybe_warn_cpp0x (CPP0X_REF_QUALIFIER);
11293 error ((flags == DTOR_FLAG)
11294 ? G_("destructors may not be ref-qualified")
11295 : G_("constructors may not be ref-qualified"));
11296 rqual = REF_QUAL_NONE;
11297 }
11298
11299 if (decl_context == FIELD
11300 && !member_function_or_else (ctype,
11301 current_class_type,
11302 flags))
11303 return error_mark_node;
11304
11305 if (flags != DTOR_FLAG)
11306 {
11307 /* It's a constructor. */
11308 if (explicitp == 1)
11309 explicitp = 2;
11310 if (virtualp)
11311 {
11312 permerror (input_location,
11313 "constructors cannot be declared %<virtual%>");
11314 virtualp = 0;
11315 }
11316 if (decl_context == FIELD
11317 && sfk != sfk_constructor)
11318 return error_mark_node;
11319 }
11320 if (decl_context == FIELD)
11321 staticp = 0;
11322 }
11323 else if (friendp)
11324 {
11325 if (virtualp)
11326 {
11327 /* Cannot be both friend and virtual. */
11328 error ("virtual functions cannot be friends");
11329 friendp = 0;
11330 }
11331 if (decl_context == NORMAL)
11332 error ("friend declaration not in class definition");
11333 if (current_function_decl && funcdef_flag)
11334 error ("can%'t define friend function %qs in a local "
11335 "class definition",
11336 name);
11337 }
11338 else if (ctype && sfk == sfk_conversion)
11339 {
11340 if (explicitp == 1)
11341 {
11342 maybe_warn_cpp0x (CPP0X_EXPLICIT_CONVERSION);
11343 explicitp = 2;
11344 }
11345 if (late_return_type_p)
11346 error ("a conversion function cannot have a trailing return type");
11347 }
11348 else if (sfk == sfk_deduction_guide)
11349 {
11350 if (explicitp == 1)
11351 explicitp = 2;
11352 }
11353
11354 tree pushed_scope = NULL_TREE;
11355 if (funcdecl_p
11356 && decl_context != FIELD
11357 && inner_declarator->u.id.qualifying_scope
11358 && CLASS_TYPE_P (inner_declarator->u.id.qualifying_scope))
11359 pushed_scope
11360 = push_scope (inner_declarator->u.id.qualifying_scope);
11361
11362 arg_types = grokparms (declarator->u.function.parameters, &parms);
11363
11364 if (pushed_scope)
11365 pop_scope (pushed_scope);
11366
11367 if (inner_declarator
11368 && inner_declarator->kind == cdk_id
11369 && inner_declarator->u.id.sfk == sfk_destructor
11370 && arg_types != void_list_node)
11371 {
11372 error ("destructors may not have parameters");
11373 arg_types = void_list_node;
11374 parms = NULL_TREE;
11375 }
11376
11377 type = build_function_type (type, arg_types);
11378
11379 tree attrs = declarator->std_attributes;
11380 if (tx_qual)
11381 {
11382 tree att = build_tree_list (tx_qual, NULL_TREE);
11383 /* transaction_safe applies to the type, but
11384 transaction_safe_dynamic applies to the function. */
11385 if (is_attribute_p ("transaction_safe", tx_qual))
11386 attrs = chainon (attrs, att);
11387 else
11388 returned_attrs = chainon (returned_attrs, att);
11389 }
11390 if (attrs)
11391 /* [dcl.fct]/2:
11392
11393 The optional attribute-specifier-seq appertains to
11394 the function type. */
11395 decl_attributes (&type, attrs, 0);
11396
11397 if (raises)
11398 type = build_exception_variant (type, raises);
11399 }
11400 break;
11401
11402 case cdk_pointer:
11403 case cdk_reference:
11404 case cdk_ptrmem:
11405 /* Filter out pointers-to-references and references-to-references.
11406 We can get these if a TYPE_DECL is used. */
11407
11408 if (TREE_CODE (type) == REFERENCE_TYPE)
11409 {
11410 if (declarator->kind != cdk_reference)
11411 {
11412 error ("cannot declare pointer to %q#T", type);
11413 type = TREE_TYPE (type);
11414 }
11415
11416 /* In C++0x, we allow reference to reference declarations
11417 that occur indirectly through typedefs [7.1.3/8 dcl.typedef]
11418 and template type arguments [14.3.1/4 temp.arg.type]. The
11419 check for direct reference to reference declarations, which
11420 are still forbidden, occurs below. Reasoning behind the change
11421 can be found in DR106, DR540, and the rvalue reference
11422 proposals. */
11423 else if (cxx_dialect == cxx98)
11424 {
11425 error ("cannot declare reference to %q#T", type);
11426 type = TREE_TYPE (type);
11427 }
11428 }
11429 else if (VOID_TYPE_P (type))
11430 {
11431 if (declarator->kind == cdk_reference)
11432 error ("cannot declare reference to %q#T", type);
11433 else if (declarator->kind == cdk_ptrmem)
11434 error ("cannot declare pointer to %q#T member", type);
11435 }
11436
11437 /* We now know that the TYPE_QUALS don't apply to the decl,
11438 but to the target of the pointer. */
11439 type_quals = TYPE_UNQUALIFIED;
11440
11441 /* This code used to handle METHOD_TYPE, but I don't think it's
11442 possible to get it here anymore. */
11443 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
11444 if (declarator->kind == cdk_ptrmem
11445 && TREE_CODE (type) == FUNCTION_TYPE)
11446 {
11447 memfn_quals |= type_memfn_quals (type);
11448 type = build_memfn_type (type,
11449 declarator->u.pointer.class_type,
11450 memfn_quals,
11451 rqual);
11452 if (type == error_mark_node)
11453 return error_mark_node;
11454
11455 rqual = REF_QUAL_NONE;
11456 memfn_quals = TYPE_UNQUALIFIED;
11457 }
11458
11459 if (TREE_CODE (type) == FUNCTION_TYPE
11460 && (type_memfn_quals (type) != TYPE_UNQUALIFIED
11461 || type_memfn_rqual (type) != REF_QUAL_NONE))
11462 error (declarator->kind == cdk_reference
11463 ? G_("cannot declare reference to qualified function type %qT")
11464 : G_("cannot declare pointer to qualified function type %qT"),
11465 type);
11466
11467 /* When the pointed-to type involves components of variable size,
11468 care must be taken to ensure that the size evaluation code is
11469 emitted early enough to dominate all the possible later uses
11470 and late enough for the variables on which it depends to have
11471 been assigned.
11472
11473 This is expected to happen automatically when the pointed-to
11474 type has a name/declaration of it's own, but special attention
11475 is required if the type is anonymous.
11476
11477 We handle the NORMAL and FIELD contexts here by inserting a
11478 dummy statement that just evaluates the size at a safe point
11479 and ensures it is not deferred until e.g. within a deeper
11480 conditional context (c++/43555).
11481
11482 We expect nothing to be needed here for PARM or TYPENAME.
11483 Evaluating the size at this point for TYPENAME would
11484 actually be incorrect, as we might be in the middle of an
11485 expression with side effects on the pointed-to type size
11486 "arguments" prior to the pointer declaration point and the
11487 size evaluation could end up prior to the side effects. */
11488
11489 if (!TYPE_NAME (type)
11490 && (decl_context == NORMAL || decl_context == FIELD)
11491 && at_function_scope_p ()
11492 && variably_modified_type_p (type, NULL_TREE))
11493 {
11494 TYPE_NAME (type) = build_decl (UNKNOWN_LOCATION, TYPE_DECL,
11495 NULL_TREE, type);
11496 add_decl_expr (TYPE_NAME (type));
11497 }
11498
11499 if (declarator->kind == cdk_reference)
11500 {
11501 /* In C++0x, the type we are creating a reference to might be
11502 a typedef which is itself a reference type. In that case,
11503 we follow the reference collapsing rules in
11504 [7.1.3/8 dcl.typedef] to create the final reference type:
11505
11506 "If a typedef TD names a type that is a reference to a type
11507 T, an attempt to create the type 'lvalue reference to cv TD'
11508 creates the type 'lvalue reference to T,' while an attempt
11509 to create the type "rvalue reference to cv TD' creates the
11510 type TD."
11511 */
11512 if (VOID_TYPE_P (type))
11513 /* We already gave an error. */;
11514 else if (TREE_CODE (type) == REFERENCE_TYPE)
11515 {
11516 if (declarator->u.reference.rvalue_ref)
11517 /* Leave type alone. */;
11518 else
11519 type = cp_build_reference_type (TREE_TYPE (type), false);
11520 }
11521 else
11522 type = cp_build_reference_type
11523 (type, declarator->u.reference.rvalue_ref);
11524
11525 /* In C++0x, we need this check for direct reference to
11526 reference declarations, which are forbidden by
11527 [8.3.2/5 dcl.ref]. Reference to reference declarations
11528 are only allowed indirectly through typedefs and template
11529 type arguments. Example:
11530
11531 void foo(int & &); // invalid ref-to-ref decl
11532
11533 typedef int & int_ref;
11534 void foo(int_ref &); // valid ref-to-ref decl
11535 */
11536 if (inner_declarator && inner_declarator->kind == cdk_reference)
11537 error ("cannot declare reference to %q#T, which is not "
11538 "a typedef or a template type argument", type);
11539 }
11540 else if (TREE_CODE (type) == METHOD_TYPE)
11541 type = build_ptrmemfunc_type (build_pointer_type (type));
11542 else if (declarator->kind == cdk_ptrmem)
11543 {
11544 gcc_assert (TREE_CODE (declarator->u.pointer.class_type)
11545 != NAMESPACE_DECL);
11546 if (declarator->u.pointer.class_type == error_mark_node)
11547 /* We will already have complained. */
11548 type = error_mark_node;
11549 else
11550 type = build_ptrmem_type (declarator->u.pointer.class_type,
11551 type);
11552 }
11553 else
11554 type = build_pointer_type (type);
11555
11556 /* Process a list of type modifier keywords (such as
11557 const or volatile) that were given inside the `*' or `&'. */
11558
11559 if (declarator->u.pointer.qualifiers)
11560 {
11561 type
11562 = cp_build_qualified_type (type,
11563 declarator->u.pointer.qualifiers);
11564 type_quals = cp_type_quals (type);
11565 }
11566
11567 /* Apply C++11 attributes to the pointer, and not to the
11568 type pointed to. This is unlike what is done for GNU
11569 attributes above. It is to comply with [dcl.ptr]/1:
11570
11571 [the optional attribute-specifier-seq (7.6.1) appertains
11572 to the pointer and not to the object pointed to]. */
11573 if (declarator->std_attributes)
11574 decl_attributes (&type, declarator->std_attributes,
11575 0);
11576
11577 ctype = NULL_TREE;
11578 break;
11579
11580 case cdk_error:
11581 break;
11582
11583 default:
11584 gcc_unreachable ();
11585 }
11586 }
11587
11588 /* A `constexpr' specifier used in an object declaration declares
11589 the object as `const'. */
11590 if (constexpr_p && innermost_code != cdk_function)
11591 {
11592 /* DR1688 says that a `constexpr' specifier in combination with
11593 `volatile' is valid. */
11594
11595 if (TREE_CODE (type) != REFERENCE_TYPE)
11596 {
11597 type_quals |= TYPE_QUAL_CONST;
11598 type = cp_build_qualified_type (type, type_quals);
11599 }
11600 }
11601
11602 if (unqualified_id && TREE_CODE (unqualified_id) == TEMPLATE_ID_EXPR
11603 && TREE_CODE (type) != FUNCTION_TYPE
11604 && TREE_CODE (type) != METHOD_TYPE
11605 && !variable_template_p (TREE_OPERAND (unqualified_id, 0)))
11606 {
11607 error ("template-id %qD used as a declarator",
11608 unqualified_id);
11609 unqualified_id = dname;
11610 }
11611
11612 /* If TYPE is a FUNCTION_TYPE, but the function name was explicitly
11613 qualified with a class-name, turn it into a METHOD_TYPE, unless
11614 we know that the function is static. We take advantage of this
11615 opportunity to do other processing that pertains to entities
11616 explicitly declared to be class members. Note that if DECLARATOR
11617 is non-NULL, we know it is a cdk_id declarator; otherwise, we
11618 would not have exited the loop above. */
11619 if (declarator
11620 && declarator->kind == cdk_id
11621 && declarator->u.id.qualifying_scope
11622 && MAYBE_CLASS_TYPE_P (declarator->u.id.qualifying_scope))
11623 {
11624 ctype = declarator->u.id.qualifying_scope;
11625 ctype = TYPE_MAIN_VARIANT (ctype);
11626 template_count = num_template_headers_for_class (ctype);
11627
11628 if (ctype == current_class_type)
11629 {
11630 if (friendp)
11631 {
11632 permerror (input_location, "member functions are implicitly "
11633 "friends of their class");
11634 friendp = 0;
11635 }
11636 else
11637 permerror (declarator->id_loc,
11638 "extra qualification %<%T::%> on member %qs",
11639 ctype, name);
11640 }
11641 else if (/* If the qualifying type is already complete, then we
11642 can skip the following checks. */
11643 !COMPLETE_TYPE_P (ctype)
11644 && (/* If the function is being defined, then
11645 qualifying type must certainly be complete. */
11646 funcdef_flag
11647 /* A friend declaration of "T::f" is OK, even if
11648 "T" is a template parameter. But, if this
11649 function is not a friend, the qualifying type
11650 must be a class. */
11651 || (!friendp && !CLASS_TYPE_P (ctype))
11652 /* For a declaration, the type need not be
11653 complete, if either it is dependent (since there
11654 is no meaningful definition of complete in that
11655 case) or the qualifying class is currently being
11656 defined. */
11657 || !(dependent_type_p (ctype)
11658 || currently_open_class (ctype)))
11659 /* Check that the qualifying type is complete. */
11660 && !complete_type_or_else (ctype, NULL_TREE))
11661 return error_mark_node;
11662 else if (TREE_CODE (type) == FUNCTION_TYPE)
11663 {
11664 if (current_class_type
11665 && (!friendp || funcdef_flag || initialized))
11666 {
11667 error (funcdef_flag || initialized
11668 ? G_("cannot define member function %<%T::%s%> "
11669 "within %qT")
11670 : G_("cannot declare member function %<%T::%s%> "
11671 "within %qT"),
11672 ctype, name, current_class_type);
11673 return error_mark_node;
11674 }
11675 }
11676 else if (typedef_p && current_class_type)
11677 {
11678 error ("cannot declare member %<%T::%s%> within %qT",
11679 ctype, name, current_class_type);
11680 return error_mark_node;
11681 }
11682 }
11683
11684 if (ctype == NULL_TREE && decl_context == FIELD && friendp == 0)
11685 ctype = current_class_type;
11686
11687 /* Now TYPE has the actual type. */
11688
11689 if (returned_attrs)
11690 {
11691 if (attrlist)
11692 *attrlist = chainon (returned_attrs, *attrlist);
11693 else
11694 attrlist = &returned_attrs;
11695 }
11696
11697 if (declarator
11698 && declarator->kind == cdk_id
11699 && declarator->std_attributes
11700 && attrlist != NULL)
11701 {
11702 /* [dcl.meaning]/1: The optional attribute-specifier-seq following
11703 a declarator-id appertains to the entity that is declared. */
11704 if (declarator->std_attributes != error_mark_node)
11705 *attrlist = chainon (*attrlist, declarator->std_attributes);
11706 else
11707 /* We should have already diagnosed the issue (c++/78344). */
11708 gcc_assert (seen_error ());
11709 }
11710
11711 /* Handle parameter packs. */
11712 if (parameter_pack_p)
11713 {
11714 if (decl_context == PARM)
11715 /* Turn the type into a pack expansion.*/
11716 type = make_pack_expansion (type);
11717 else
11718 error ("non-parameter %qs cannot be a parameter pack", name);
11719 }
11720
11721 if ((decl_context == FIELD || decl_context == PARM)
11722 && !processing_template_decl
11723 && variably_modified_type_p (type, NULL_TREE))
11724 {
11725 if (decl_context == FIELD)
11726 error ("data member may not have variably modified type %qT", type);
11727 else
11728 error ("parameter may not have variably modified type %qT", type);
11729 type = error_mark_node;
11730 }
11731
11732 if (explicitp == 1 || (explicitp && friendp))
11733 {
11734 /* [dcl.fct.spec] (C++11) The explicit specifier shall be used only
11735 in the declaration of a constructor or conversion function within
11736 a class definition. */
11737 if (!current_class_type)
11738 error_at (declspecs->locations[ds_explicit],
11739 "%<explicit%> outside class declaration");
11740 else if (friendp)
11741 error_at (declspecs->locations[ds_explicit],
11742 "%<explicit%> in friend declaration");
11743 else
11744 error_at (declspecs->locations[ds_explicit],
11745 "only declarations of constructors and conversion operators "
11746 "can be %<explicit%>");
11747 explicitp = 0;
11748 }
11749
11750 if (storage_class == sc_mutable)
11751 {
11752 if (decl_context != FIELD || friendp)
11753 {
11754 error ("non-member %qs cannot be declared %<mutable%>", name);
11755 storage_class = sc_none;
11756 }
11757 else if (decl_context == TYPENAME || typedef_p)
11758 {
11759 error ("non-object member %qs cannot be declared %<mutable%>", name);
11760 storage_class = sc_none;
11761 }
11762 else if (TREE_CODE (type) == FUNCTION_TYPE
11763 || TREE_CODE (type) == METHOD_TYPE)
11764 {
11765 error ("function %qs cannot be declared %<mutable%>", name);
11766 storage_class = sc_none;
11767 }
11768 else if (staticp)
11769 {
11770 error ("static %qs cannot be declared %<mutable%>", name);
11771 storage_class = sc_none;
11772 }
11773 else if (type_quals & TYPE_QUAL_CONST)
11774 {
11775 error ("const %qs cannot be declared %<mutable%>", name);
11776 storage_class = sc_none;
11777 }
11778 else if (TREE_CODE (type) == REFERENCE_TYPE)
11779 {
11780 permerror (input_location, "reference %qs cannot be declared "
11781 "%<mutable%>", name);
11782 storage_class = sc_none;
11783 }
11784 }
11785
11786 /* If this is declaring a typedef name, return a TYPE_DECL. */
11787 if (typedef_p && decl_context != TYPENAME)
11788 {
11789 tree decl;
11790
11791 /* This declaration:
11792
11793 typedef void f(int) const;
11794
11795 declares a function type which is not a member of any
11796 particular class, but which is cv-qualified; for
11797 example "f S::*" declares a pointer to a const-qualified
11798 member function of S. We record the cv-qualification in the
11799 function type. */
11800 if ((rqual || memfn_quals) && TREE_CODE (type) == FUNCTION_TYPE)
11801 {
11802 type = apply_memfn_quals (type, memfn_quals, rqual);
11803
11804 /* We have now dealt with these qualifiers. */
11805 memfn_quals = TYPE_UNQUALIFIED;
11806 rqual = REF_QUAL_NONE;
11807 }
11808
11809 if (type_uses_auto (type))
11810 {
11811 error ("typedef declared %<auto%>");
11812 type = error_mark_node;
11813 }
11814
11815 if (reqs)
11816 error_at (location_of (reqs), "requires-clause on typedef");
11817
11818 if (id_declarator && declarator->u.id.qualifying_scope)
11819 {
11820 error ("typedef name may not be a nested-name-specifier");
11821 type = error_mark_node;
11822 }
11823
11824 if (decl_context == FIELD)
11825 decl = build_lang_decl (TYPE_DECL, unqualified_id, type);
11826 else
11827 decl = build_decl (input_location, TYPE_DECL, unqualified_id, type);
11828
11829 if (decl_context != FIELD)
11830 {
11831 if (!current_function_decl)
11832 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
11833 else if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (current_function_decl)
11834 || (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P
11835 (current_function_decl)))
11836 /* The TYPE_DECL is "abstract" because there will be
11837 clones of this constructor/destructor, and there will
11838 be copies of this TYPE_DECL generated in those
11839 clones. The decloning optimization (for space) may
11840 revert this subsequently if it determines that
11841 the clones should share a common implementation. */
11842 DECL_ABSTRACT_P (decl) = true;
11843 }
11844 else if (current_class_type
11845 && constructor_name_p (unqualified_id, current_class_type))
11846 permerror (input_location, "ISO C++ forbids nested type %qD with same name "
11847 "as enclosing class",
11848 unqualified_id);
11849
11850 /* If the user declares "typedef struct {...} foo" then the
11851 struct will have an anonymous name. Fill that name in now.
11852 Nothing can refer to it, so nothing needs know about the name
11853 change. */
11854 if (type != error_mark_node
11855 && unqualified_id
11856 && TYPE_NAME (type)
11857 && TREE_CODE (TYPE_NAME (type)) == TYPE_DECL
11858 && TYPE_UNNAMED_P (type)
11859 && declspecs->type_definition_p
11860 && attributes_naming_typedef_ok (*attrlist)
11861 && cp_type_quals (type) == TYPE_UNQUALIFIED)
11862 name_unnamed_type (type, decl);
11863
11864 if (signed_p
11865 || (typedef_decl && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl)))
11866 C_TYPEDEF_EXPLICITLY_SIGNED (decl) = 1;
11867
11868 bad_specifiers (decl, BSP_TYPE, virtualp,
11869 memfn_quals != TYPE_UNQUALIFIED,
11870 inlinep, friendp, raises != NULL_TREE);
11871
11872 if (decl_spec_seq_has_spec_p (declspecs, ds_alias))
11873 /* Acknowledge that this was written:
11874 `using analias = atype;'. */
11875 TYPE_DECL_ALIAS_P (decl) = 1;
11876
11877 return decl;
11878 }
11879
11880 /* Detect the case of an array type of unspecified size
11881 which came, as such, direct from a typedef name.
11882 We must copy the type, so that the array's domain can be
11883 individually set by the object's initializer. */
11884
11885 if (type && typedef_type
11886 && TREE_CODE (type) == ARRAY_TYPE && !TYPE_DOMAIN (type)
11887 && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (typedef_type))
11888 type = build_cplus_array_type (TREE_TYPE (type), NULL_TREE);
11889
11890 /* Detect where we're using a typedef of function type to declare a
11891 function. PARMS will not be set, so we must create it now. */
11892
11893 if (type == typedef_type && TREE_CODE (type) == FUNCTION_TYPE)
11894 {
11895 tree decls = NULL_TREE;
11896 tree args;
11897
11898 for (args = TYPE_ARG_TYPES (type);
11899 args && args != void_list_node;
11900 args = TREE_CHAIN (args))
11901 {
11902 tree decl = cp_build_parm_decl (NULL_TREE, NULL_TREE,
11903 TREE_VALUE (args));
11904
11905 DECL_CHAIN (decl) = decls;
11906 decls = decl;
11907 }
11908
11909 parms = nreverse (decls);
11910
11911 if (decl_context != TYPENAME)
11912 {
11913 /* The qualifiers on the function type become the qualifiers on
11914 the non-static member function. */
11915 memfn_quals |= type_memfn_quals (type);
11916 rqual = type_memfn_rqual (type);
11917 type_quals = TYPE_UNQUALIFIED;
11918 }
11919 }
11920
11921 /* If this is a type name (such as, in a cast or sizeof),
11922 compute the type and return it now. */
11923
11924 if (decl_context == TYPENAME)
11925 {
11926 /* Note that here we don't care about type_quals. */
11927
11928 /* Special case: "friend class foo" looks like a TYPENAME context. */
11929 if (friendp)
11930 {
11931 if (inlinep)
11932 {
11933 error ("%<inline%> specified for friend class declaration");
11934 inlinep = 0;
11935 }
11936
11937 if (!current_aggr)
11938 {
11939 /* Don't allow friend declaration without a class-key. */
11940 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
11941 permerror (input_location, "template parameters cannot be friends");
11942 else if (TREE_CODE (type) == TYPENAME_TYPE)
11943 permerror (input_location, "friend declaration requires class-key, "
11944 "i.e. %<friend class %T::%D%>",
11945 TYPE_CONTEXT (type), TYPENAME_TYPE_FULLNAME (type));
11946 else
11947 permerror (input_location, "friend declaration requires class-key, "
11948 "i.e. %<friend %#T%>",
11949 type);
11950 }
11951
11952 /* Only try to do this stuff if we didn't already give up. */
11953 if (type != integer_type_node)
11954 {
11955 /* A friendly class? */
11956 if (current_class_type)
11957 make_friend_class (current_class_type, TYPE_MAIN_VARIANT (type),
11958 /*complain=*/true);
11959 else
11960 error ("trying to make class %qT a friend of global scope",
11961 type);
11962
11963 type = void_type_node;
11964 }
11965 }
11966 else if (memfn_quals || rqual)
11967 {
11968 if (ctype == NULL_TREE
11969 && TREE_CODE (type) == METHOD_TYPE)
11970 ctype = TYPE_METHOD_BASETYPE (type);
11971
11972 if (ctype)
11973 type = build_memfn_type (type, ctype, memfn_quals, rqual);
11974 /* Core issue #547: need to allow this in template type args.
11975 Allow it in general in C++11 for alias-declarations. */
11976 else if ((template_type_arg || cxx_dialect >= cxx11)
11977 && TREE_CODE (type) == FUNCTION_TYPE)
11978 type = apply_memfn_quals (type, memfn_quals, rqual);
11979 else
11980 error ("invalid qualifiers on non-member function type");
11981 }
11982
11983 if (reqs)
11984 error_at (location_of (reqs), "requires-clause on type-id");
11985
11986 return type;
11987 }
11988 else if (unqualified_id == NULL_TREE && decl_context != PARM
11989 && decl_context != CATCHPARM
11990 && TREE_CODE (type) != UNION_TYPE
11991 && ! bitfield
11992 && innermost_code != cdk_decomp)
11993 {
11994 error ("abstract declarator %qT used as declaration", type);
11995 return error_mark_node;
11996 }
11997
11998 if (!FUNC_OR_METHOD_TYPE_P (type))
11999 {
12000 /* Only functions may be declared using an operator-function-id. */
12001 if (dname && IDENTIFIER_ANY_OP_P (dname))
12002 {
12003 error ("declaration of %qD as non-function", dname);
12004 return error_mark_node;
12005 }
12006
12007 if (reqs)
12008 error_at (location_of (reqs),
12009 "requires-clause on declaration of non-function type %qT",
12010 type);
12011 }
12012
12013 /* We don't check parameter types here because we can emit a better
12014 error message later. */
12015 if (decl_context != PARM)
12016 {
12017 type = check_var_type (unqualified_id, type);
12018 if (type == error_mark_node)
12019 return error_mark_node;
12020 }
12021
12022 /* Now create the decl, which may be a VAR_DECL, a PARM_DECL
12023 or a FUNCTION_DECL, depending on DECL_CONTEXT and TYPE. */
12024
12025 if (decl_context == PARM || decl_context == CATCHPARM)
12026 {
12027 if (ctype || in_namespace)
12028 error ("cannot use %<::%> in parameter declaration");
12029
12030 if (type_uses_auto (type)
12031 && !(cxx_dialect >= cxx17 && template_parm_flag))
12032 {
12033 if (cxx_dialect >= cxx14)
12034 error ("%<auto%> parameter not permitted in this context");
12035 else
12036 error ("parameter declared %<auto%>");
12037 type = error_mark_node;
12038 }
12039
12040 /* A parameter declared as an array of T is really a pointer to T.
12041 One declared as a function is really a pointer to a function.
12042 One declared as a member is really a pointer to member. */
12043
12044 if (TREE_CODE (type) == ARRAY_TYPE)
12045 {
12046 /* Transfer const-ness of array into that of type pointed to. */
12047 type = build_pointer_type (TREE_TYPE (type));
12048 type_quals = TYPE_UNQUALIFIED;
12049 array_parameter_p = true;
12050 }
12051 else if (TREE_CODE (type) == FUNCTION_TYPE)
12052 type = build_pointer_type (type);
12053 }
12054
12055 if (ctype && TREE_CODE (type) == FUNCTION_TYPE && staticp < 2
12056 && !(identifier_p (unqualified_id)
12057 && IDENTIFIER_NEWDEL_OP_P (unqualified_id)))
12058 {
12059 cp_cv_quals real_quals = memfn_quals;
12060 if (cxx_dialect < cxx14 && constexpr_p
12061 && sfk != sfk_constructor && sfk != sfk_destructor)
12062 real_quals |= TYPE_QUAL_CONST;
12063 type = build_memfn_type (type, ctype, real_quals, rqual);
12064 }
12065
12066 {
12067 tree decl = NULL_TREE;
12068
12069 if (decl_context == PARM)
12070 {
12071 decl = cp_build_parm_decl (NULL_TREE, unqualified_id, type);
12072 DECL_ARRAY_PARAMETER_P (decl) = array_parameter_p;
12073
12074 bad_specifiers (decl, BSP_PARM, virtualp,
12075 memfn_quals != TYPE_UNQUALIFIED,
12076 inlinep, friendp, raises != NULL_TREE);
12077 }
12078 else if (decl_context == FIELD)
12079 {
12080 if (!staticp && !friendp && TREE_CODE (type) != METHOD_TYPE)
12081 if (tree auto_node = type_uses_auto (type))
12082 {
12083 location_t loc = declspecs->locations[ds_type_spec];
12084 if (CLASS_PLACEHOLDER_TEMPLATE (auto_node))
12085 error_at (loc, "invalid use of template-name %qE without an "
12086 "argument list",
12087 CLASS_PLACEHOLDER_TEMPLATE (auto_node));
12088 else
12089 error_at (loc, "non-static data member declared with "
12090 "placeholder %qT", auto_node);
12091 type = error_mark_node;
12092 }
12093
12094 /* The C99 flexible array extension. */
12095 if (!staticp && TREE_CODE (type) == ARRAY_TYPE
12096 && TYPE_DOMAIN (type) == NULL_TREE)
12097 {
12098 if (ctype
12099 && (TREE_CODE (ctype) == UNION_TYPE
12100 || TREE_CODE (ctype) == QUAL_UNION_TYPE))
12101 {
12102 error ("flexible array member in union");
12103 type = error_mark_node;
12104 }
12105 else
12106 {
12107 /* Array is a flexible member. */
12108 if (in_system_header_at (input_location))
12109 /* Do not warn on flexible array members in system
12110 headers because glibc uses them. */;
12111 else if (name)
12112 pedwarn (input_location, OPT_Wpedantic,
12113 "ISO C++ forbids flexible array member %qs", name);
12114 else
12115 pedwarn (input_location, OPT_Wpedantic,
12116 "ISO C++ forbids flexible array members");
12117
12118 /* Flexible array member has a null domain. */
12119 type = build_cplus_array_type (TREE_TYPE (type), NULL_TREE);
12120 }
12121 }
12122
12123 if (type == error_mark_node)
12124 {
12125 /* Happens when declaring arrays of sizes which
12126 are error_mark_node, for example. */
12127 decl = NULL_TREE;
12128 }
12129 else if (in_namespace && !friendp)
12130 {
12131 /* Something like struct S { int N::j; }; */
12132 error ("invalid use of %<::%>");
12133 return error_mark_node;
12134 }
12135 else if (TREE_CODE (type) == FUNCTION_TYPE
12136 || TREE_CODE (type) == METHOD_TYPE)
12137 {
12138 int publicp = 0;
12139 tree function_context;
12140
12141 if (friendp == 0)
12142 {
12143 /* This should never happen in pure C++ (the check
12144 could be an assert). It could happen in
12145 Objective-C++ if someone writes invalid code that
12146 uses a function declaration for an instance
12147 variable or property (instance variables and
12148 properties are parsed as FIELD_DECLs, but they are
12149 part of an Objective-C class, not a C++ class).
12150 That code is invalid and is caught by this
12151 check. */
12152 if (!ctype)
12153 {
12154 error ("declaration of function %qD in invalid context",
12155 unqualified_id);
12156 return error_mark_node;
12157 }
12158
12159 /* ``A union may [ ... ] not [ have ] virtual functions.''
12160 ARM 9.5 */
12161 if (virtualp && TREE_CODE (ctype) == UNION_TYPE)
12162 {
12163 error ("function %qD declared %<virtual%> inside a union",
12164 unqualified_id);
12165 return error_mark_node;
12166 }
12167
12168 if (virtualp
12169 && identifier_p (unqualified_id)
12170 && IDENTIFIER_NEWDEL_OP_P (unqualified_id))
12171 {
12172 error ("%qD cannot be declared %<virtual%>, since it "
12173 "is always static", unqualified_id);
12174 virtualp = 0;
12175 }
12176 }
12177
12178 /* Check that the name used for a destructor makes sense. */
12179 if (sfk == sfk_destructor)
12180 {
12181 tree uqname = id_declarator->u.id.unqualified_name;
12182
12183 if (!ctype)
12184 {
12185 gcc_assert (friendp);
12186 error ("expected qualified name in friend declaration "
12187 "for destructor %qD", uqname);
12188 return error_mark_node;
12189 }
12190
12191 if (!check_dtor_name (ctype, TREE_OPERAND (uqname, 0)))
12192 {
12193 error ("declaration of %qD as member of %qT",
12194 uqname, ctype);
12195 return error_mark_node;
12196 }
12197 if (concept_p)
12198 {
12199 error ("a destructor cannot be %<concept%>");
12200 return error_mark_node;
12201 }
12202 if (constexpr_p)
12203 {
12204 error ("a destructor cannot be %<constexpr%>");
12205 return error_mark_node;
12206 }
12207 }
12208 else if (sfk == sfk_constructor && friendp && !ctype)
12209 {
12210 error ("expected qualified name in friend declaration "
12211 "for constructor %qD",
12212 id_declarator->u.id.unqualified_name);
12213 return error_mark_node;
12214 }
12215 if (sfk == sfk_constructor)
12216 if (concept_p)
12217 {
12218 error ("a constructor cannot be %<concept%>");
12219 return error_mark_node;
12220 }
12221 if (concept_p)
12222 {
12223 error ("a concept cannot be a member function");
12224 concept_p = false;
12225 }
12226
12227 if (TREE_CODE (unqualified_id) == TEMPLATE_ID_EXPR)
12228 {
12229 tree tmpl = TREE_OPERAND (unqualified_id, 0);
12230 if (variable_template_p (tmpl))
12231 {
12232 error ("specialization of variable template %qD "
12233 "declared as function", tmpl);
12234 inform (DECL_SOURCE_LOCATION (tmpl),
12235 "variable template declared here");
12236 return error_mark_node;
12237 }
12238 }
12239
12240 /* Tell grokfndecl if it needs to set TREE_PUBLIC on the node. */
12241 function_context = (ctype != NULL_TREE) ?
12242 decl_function_context (TYPE_MAIN_DECL (ctype)) : NULL_TREE;
12243 publicp = (! friendp || ! staticp)
12244 && function_context == NULL_TREE;
12245
12246 if (late_return_type_p)
12247 TYPE_HAS_LATE_RETURN_TYPE (type) = 1;
12248
12249 decl = grokfndecl (ctype, type,
12250 TREE_CODE (unqualified_id) != TEMPLATE_ID_EXPR
12251 ? unqualified_id : dname,
12252 parms,
12253 unqualified_id,
12254 reqs,
12255 virtualp, flags, memfn_quals, rqual, raises,
12256 friendp ? -1 : 0, friendp, publicp,
12257 inlinep | (2 * constexpr_p) | (4 * concept_p),
12258 initialized == SD_DELETED, sfk,
12259 funcdef_flag, template_count, in_namespace,
12260 attrlist, declarator->id_loc);
12261 decl = set_virt_specifiers (decl, virt_specifiers);
12262 if (decl == NULL_TREE)
12263 return error_mark_node;
12264 #if 0
12265 /* This clobbers the attrs stored in `decl' from `attrlist'. */
12266 /* The decl and setting of decl_attr is also turned off. */
12267 decl = build_decl_attribute_variant (decl, decl_attr);
12268 #endif
12269
12270 /* [class.conv.ctor]
12271
12272 A constructor declared without the function-specifier
12273 explicit that can be called with a single parameter
12274 specifies a conversion from the type of its first
12275 parameter to the type of its class. Such a constructor
12276 is called a converting constructor. */
12277 if (explicitp == 2)
12278 DECL_NONCONVERTING_P (decl) = 1;
12279 }
12280 else if (!staticp && !dependent_type_p (type)
12281 && !COMPLETE_TYPE_P (complete_type (type))
12282 && (!complete_or_array_type_p (type)
12283 || initialized == 0))
12284 {
12285 if (TREE_CODE (type) != ARRAY_TYPE
12286 || !COMPLETE_TYPE_P (TREE_TYPE (type)))
12287 {
12288 if (unqualified_id)
12289 {
12290 error ("field %qD has incomplete type %qT",
12291 unqualified_id, type);
12292 cxx_incomplete_type_inform (strip_array_types (type));
12293 }
12294 else
12295 error ("name %qT has incomplete type", type);
12296
12297 type = error_mark_node;
12298 decl = NULL_TREE;
12299 }
12300 }
12301 else
12302 {
12303 if (friendp)
12304 {
12305 error ("%qE is neither function nor member function; "
12306 "cannot be declared friend", unqualified_id);
12307 return error_mark_node;
12308 }
12309 decl = NULL_TREE;
12310 }
12311
12312 if (friendp)
12313 {
12314 /* Friends are treated specially. */
12315 if (ctype == current_class_type)
12316 ; /* We already issued a permerror. */
12317 else if (decl && DECL_NAME (decl))
12318 {
12319 if (template_class_depth (current_class_type) == 0)
12320 {
12321 decl = check_explicit_specialization
12322 (unqualified_id, decl, template_count,
12323 2 * funcdef_flag + 4);
12324 if (decl == error_mark_node)
12325 return error_mark_node;
12326 }
12327
12328 decl = do_friend (ctype, unqualified_id, decl,
12329 *attrlist, flags,
12330 funcdef_flag);
12331 return decl;
12332 }
12333 else
12334 return error_mark_node;
12335 }
12336
12337 /* Structure field. It may not be a function, except for C++. */
12338
12339 if (decl == NULL_TREE)
12340 {
12341 if (staticp)
12342 {
12343 /* C++ allows static class members. All other work
12344 for this is done by grokfield. */
12345 decl = build_lang_decl_loc (declarator
12346 ? declarator->id_loc
12347 : input_location,
12348 VAR_DECL, unqualified_id, type);
12349 set_linkage_for_static_data_member (decl);
12350 if (concept_p)
12351 error ("static data member %qE declared %<concept%>",
12352 unqualified_id);
12353 else if (constexpr_p && !initialized)
12354 {
12355 error ("%<constexpr%> static data member %qD must have an "
12356 "initializer", decl);
12357 constexpr_p = false;
12358 }
12359
12360 if (inlinep)
12361 mark_inline_variable (decl);
12362
12363 if (!DECL_VAR_DECLARED_INLINE_P (decl)
12364 && !(cxx_dialect >= cxx17 && constexpr_p))
12365 /* Even if there is an in-class initialization, DECL
12366 is considered undefined until an out-of-class
12367 definition is provided, unless this is an inline
12368 variable. */
12369 DECL_EXTERNAL (decl) = 1;
12370
12371 if (thread_p)
12372 {
12373 CP_DECL_THREAD_LOCAL_P (decl) = true;
12374 if (!processing_template_decl)
12375 set_decl_tls_model (decl, decl_default_tls_model (decl));
12376 if (declspecs->gnu_thread_keyword_p)
12377 SET_DECL_GNU_TLS_P (decl);
12378 }
12379 }
12380 else
12381 {
12382 if (concept_p)
12383 error ("non-static data member %qE declared %<concept%>",
12384 unqualified_id);
12385 else if (constexpr_p)
12386 {
12387 error ("non-static data member %qE declared %<constexpr%>",
12388 unqualified_id);
12389 constexpr_p = false;
12390 }
12391 decl = build_decl (input_location,
12392 FIELD_DECL, unqualified_id, type);
12393 DECL_NONADDRESSABLE_P (decl) = bitfield;
12394 if (bitfield && !unqualified_id)
12395 {
12396 TREE_NO_WARNING (decl) = 1;
12397 DECL_PADDING_P (decl) = 1;
12398 }
12399
12400 if (storage_class == sc_mutable)
12401 {
12402 DECL_MUTABLE_P (decl) = 1;
12403 storage_class = sc_none;
12404 }
12405
12406 if (initialized)
12407 {
12408 /* An attempt is being made to initialize a non-static
12409 member. This is new in C++11. */
12410 maybe_warn_cpp0x (CPP0X_NSDMI);
12411
12412 /* If this has been parsed with static storage class, but
12413 errors forced staticp to be cleared, ensure NSDMI is
12414 not present. */
12415 if (declspecs->storage_class == sc_static)
12416 DECL_INITIAL (decl) = error_mark_node;
12417 }
12418 }
12419
12420 bad_specifiers (decl, BSP_FIELD, virtualp,
12421 memfn_quals != TYPE_UNQUALIFIED,
12422 staticp ? false : inlinep, friendp,
12423 raises != NULL_TREE);
12424 }
12425 }
12426 else if (TREE_CODE (type) == FUNCTION_TYPE
12427 || TREE_CODE (type) == METHOD_TYPE)
12428 {
12429 tree original_name;
12430 int publicp = 0;
12431
12432 if (!unqualified_id)
12433 return error_mark_node;
12434
12435 if (TREE_CODE (unqualified_id) == TEMPLATE_ID_EXPR)
12436 original_name = dname;
12437 else
12438 original_name = unqualified_id;
12439 // FIXME:gcc_assert (original_name == dname);
12440
12441 if (storage_class == sc_auto)
12442 error ("storage class %<auto%> invalid for function %qs", name);
12443 else if (storage_class == sc_register)
12444 error ("storage class %<register%> invalid for function %qs", name);
12445 else if (thread_p)
12446 {
12447 if (declspecs->gnu_thread_keyword_p)
12448 error ("storage class %<__thread%> invalid for function %qs",
12449 name);
12450 else
12451 error ("storage class %<thread_local%> invalid for function %qs",
12452 name);
12453 }
12454
12455 if (virt_specifiers)
12456 error ("virt-specifiers in %qs not allowed outside a class definition", name);
12457 /* Function declaration not at top level.
12458 Storage classes other than `extern' are not allowed
12459 and `extern' makes no difference. */
12460 if (! toplevel_bindings_p ()
12461 && (storage_class == sc_static
12462 || decl_spec_seq_has_spec_p (declspecs, ds_inline))
12463 && pedantic)
12464 {
12465 if (storage_class == sc_static)
12466 pedwarn (input_location, OPT_Wpedantic,
12467 "%<static%> specifier invalid for function %qs "
12468 "declared out of global scope", name);
12469 else
12470 pedwarn (input_location, OPT_Wpedantic,
12471 "%<inline%> specifier invalid for function %qs "
12472 "declared out of global scope", name);
12473 }
12474
12475 if (ctype == NULL_TREE)
12476 {
12477 if (virtualp)
12478 {
12479 error ("virtual non-class function %qs", name);
12480 virtualp = 0;
12481 }
12482 else if (sfk == sfk_constructor
12483 || sfk == sfk_destructor)
12484 {
12485 error (funcdef_flag
12486 ? G_("%qs defined in a non-class scope")
12487 : G_("%qs declared in a non-class scope"), name);
12488 sfk = sfk_none;
12489 }
12490 }
12491
12492 /* Record whether the function is public. */
12493 publicp = (ctype != NULL_TREE
12494 || storage_class != sc_static);
12495
12496 if (late_return_type_p)
12497 TYPE_HAS_LATE_RETURN_TYPE (type) = 1;
12498
12499 decl = grokfndecl (ctype, type, original_name, parms, unqualified_id,
12500 reqs, virtualp, flags, memfn_quals, rqual, raises,
12501 1, friendp,
12502 publicp,
12503 inlinep | (2 * constexpr_p) | (4 * concept_p),
12504 initialized == SD_DELETED,
12505 sfk,
12506 funcdef_flag,
12507 template_count, in_namespace, attrlist,
12508 declarator->id_loc);
12509 if (decl == NULL_TREE)
12510 return error_mark_node;
12511
12512 if (explicitp == 2)
12513 DECL_NONCONVERTING_P (decl) = 1;
12514 if (staticp == 1)
12515 {
12516 int invalid_static = 0;
12517
12518 /* Don't allow a static member function in a class, and forbid
12519 declaring main to be static. */
12520 if (TREE_CODE (type) == METHOD_TYPE)
12521 {
12522 permerror (input_location, "cannot declare member function %qD to have "
12523 "static linkage", decl);
12524 invalid_static = 1;
12525 }
12526 else if (current_function_decl)
12527 {
12528 /* 7.1.1: There can be no static function declarations within a
12529 block. */
12530 error ("cannot declare static function inside another function");
12531 invalid_static = 1;
12532 }
12533
12534 if (invalid_static)
12535 {
12536 staticp = 0;
12537 storage_class = sc_none;
12538 }
12539 }
12540 }
12541 else
12542 {
12543 /* It's a variable. */
12544
12545 /* An uninitialized decl with `extern' is a reference. */
12546 decl = grokvardecl (type, dname, unqualified_id,
12547 declspecs,
12548 initialized,
12549 type_quals,
12550 inlinep,
12551 concept_p,
12552 template_count,
12553 ctype ? ctype : in_namespace);
12554 if (decl == NULL_TREE)
12555 return error_mark_node;
12556
12557 bad_specifiers (decl, BSP_VAR, virtualp,
12558 memfn_quals != TYPE_UNQUALIFIED,
12559 inlinep, friendp, raises != NULL_TREE);
12560
12561 if (ctype)
12562 {
12563 DECL_CONTEXT (decl) = ctype;
12564 if (staticp == 1)
12565 {
12566 permerror (input_location, "%<static%> may not be used when defining "
12567 "(as opposed to declaring) a static data member");
12568 staticp = 0;
12569 storage_class = sc_none;
12570 }
12571 if (storage_class == sc_register && TREE_STATIC (decl))
12572 {
12573 error ("static member %qD declared %<register%>", decl);
12574 storage_class = sc_none;
12575 }
12576 if (storage_class == sc_extern && pedantic)
12577 {
12578 pedwarn (input_location, OPT_Wpedantic,
12579 "cannot explicitly declare member %q#D to have "
12580 "extern linkage", decl);
12581 storage_class = sc_none;
12582 }
12583 }
12584 else if (constexpr_p && DECL_EXTERNAL (decl))
12585 {
12586 error ("declaration of %<constexpr%> variable %qD "
12587 "is not a definition", decl);
12588 constexpr_p = false;
12589 }
12590
12591 if (inlinep)
12592 mark_inline_variable (decl);
12593 if (innermost_code == cdk_decomp)
12594 {
12595 gcc_assert (declarator && declarator->kind == cdk_decomp);
12596 DECL_SOURCE_LOCATION (decl) = declarator->id_loc;
12597 DECL_ARTIFICIAL (decl) = 1;
12598 fit_decomposition_lang_decl (decl, NULL_TREE);
12599 }
12600 }
12601
12602 if (VAR_P (decl) && !initialized)
12603 if (tree auto_node = type_uses_auto (type))
12604 if (!CLASS_PLACEHOLDER_TEMPLATE (auto_node))
12605 {
12606 location_t loc = declspecs->locations[ds_type_spec];
12607 error_at (loc, "declaration of %q#D has no initializer", decl);
12608 TREE_TYPE (decl) = error_mark_node;
12609 }
12610
12611 if (storage_class == sc_extern && initialized && !funcdef_flag)
12612 {
12613 if (toplevel_bindings_p ())
12614 {
12615 /* It's common practice (and completely valid) to have a const
12616 be initialized and declared extern. */
12617 if (!(type_quals & TYPE_QUAL_CONST))
12618 warning (0, "%qs initialized and declared %<extern%>", name);
12619 }
12620 else
12621 {
12622 error ("%qs has both %<extern%> and initializer", name);
12623 return error_mark_node;
12624 }
12625 }
12626
12627 /* Record `register' declaration for warnings on &
12628 and in case doing stupid register allocation. */
12629
12630 if (storage_class == sc_register)
12631 {
12632 DECL_REGISTER (decl) = 1;
12633 /* Warn about register storage specifiers on PARM_DECLs. */
12634 if (TREE_CODE (decl) == PARM_DECL)
12635 {
12636 if (cxx_dialect >= cxx17)
12637 pedwarn (DECL_SOURCE_LOCATION (decl), OPT_Wregister,
12638 "ISO C++17 does not allow %<register%> storage "
12639 "class specifier");
12640 else
12641 warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wregister,
12642 "%<register%> storage class specifier used");
12643 }
12644 }
12645 else if (storage_class == sc_extern)
12646 DECL_THIS_EXTERN (decl) = 1;
12647 else if (storage_class == sc_static)
12648 DECL_THIS_STATIC (decl) = 1;
12649
12650 /* Set constexpr flag on vars (functions got it in grokfndecl). */
12651 if (constexpr_p && VAR_P (decl))
12652 DECL_DECLARED_CONSTEXPR_P (decl) = true;
12653
12654 /* Record constancy and volatility on the DECL itself . There's
12655 no need to do this when processing a template; we'll do this
12656 for the instantiated declaration based on the type of DECL. */
12657 if (!processing_template_decl)
12658 cp_apply_type_quals_to_decl (type_quals, decl);
12659
12660 return decl;
12661 }
12662 }
12663
12664 /* Subroutine of start_function. Ensure that each of the parameter
12665 types (as listed in PARMS) is complete, as is required for a
12666 function definition. */
12667
12668 static void
require_complete_types_for_parms(tree parms)12669 require_complete_types_for_parms (tree parms)
12670 {
12671 for (; parms; parms = DECL_CHAIN (parms))
12672 {
12673 if (dependent_type_p (TREE_TYPE (parms)))
12674 continue;
12675 if (!VOID_TYPE_P (TREE_TYPE (parms))
12676 && complete_type_or_else (TREE_TYPE (parms), parms))
12677 {
12678 relayout_decl (parms);
12679 DECL_ARG_TYPE (parms) = type_passed_as (TREE_TYPE (parms));
12680
12681 maybe_warn_parm_abi (TREE_TYPE (parms),
12682 DECL_SOURCE_LOCATION (parms));
12683 }
12684 else
12685 /* grokparms or complete_type_or_else will have already issued
12686 an error. */
12687 TREE_TYPE (parms) = error_mark_node;
12688 }
12689 }
12690
12691 /* Returns nonzero if T is a local variable. */
12692
12693 int
local_variable_p(const_tree t)12694 local_variable_p (const_tree t)
12695 {
12696 if ((VAR_P (t)
12697 /* A VAR_DECL with a context that is a _TYPE is a static data
12698 member. */
12699 && !TYPE_P (CP_DECL_CONTEXT (t))
12700 /* Any other non-local variable must be at namespace scope. */
12701 && !DECL_NAMESPACE_SCOPE_P (t))
12702 || (TREE_CODE (t) == PARM_DECL))
12703 return 1;
12704
12705 return 0;
12706 }
12707
12708 /* Like local_variable_p, but suitable for use as a tree-walking
12709 function. */
12710
12711 static tree
local_variable_p_walkfn(tree * tp,int * walk_subtrees,void *)12712 local_variable_p_walkfn (tree *tp, int *walk_subtrees,
12713 void * /*data*/)
12714 {
12715 if (local_variable_p (*tp)
12716 && (!DECL_ARTIFICIAL (*tp) || DECL_NAME (*tp) == this_identifier))
12717 return *tp;
12718 else if (TYPE_P (*tp))
12719 *walk_subtrees = 0;
12720
12721 return NULL_TREE;
12722 }
12723
12724 /* Check that ARG, which is a default-argument expression for a
12725 parameter DECL, is valid. Returns ARG, or ERROR_MARK_NODE, if
12726 something goes wrong. DECL may also be a _TYPE node, rather than a
12727 DECL, if there is no DECL available. */
12728
12729 tree
check_default_argument(tree decl,tree arg,tsubst_flags_t complain)12730 check_default_argument (tree decl, tree arg, tsubst_flags_t complain)
12731 {
12732 tree var;
12733 tree decl_type;
12734
12735 if (TREE_CODE (arg) == DEFAULT_ARG)
12736 /* We get a DEFAULT_ARG when looking at an in-class declaration
12737 with a default argument. Ignore the argument for now; we'll
12738 deal with it after the class is complete. */
12739 return arg;
12740
12741 if (TYPE_P (decl))
12742 {
12743 decl_type = decl;
12744 decl = NULL_TREE;
12745 }
12746 else
12747 decl_type = TREE_TYPE (decl);
12748
12749 if (arg == error_mark_node
12750 || decl == error_mark_node
12751 || TREE_TYPE (arg) == error_mark_node
12752 || decl_type == error_mark_node)
12753 /* Something already went wrong. There's no need to check
12754 further. */
12755 return error_mark_node;
12756
12757 /* [dcl.fct.default]
12758
12759 A default argument expression is implicitly converted to the
12760 parameter type. */
12761 ++cp_unevaluated_operand;
12762 /* Avoid digest_init clobbering the initializer. */
12763 tree carg = BRACE_ENCLOSED_INITIALIZER_P (arg) ? unshare_expr (arg): arg;
12764 perform_implicit_conversion_flags (decl_type, carg, complain,
12765 LOOKUP_IMPLICIT);
12766 --cp_unevaluated_operand;
12767
12768 /* Avoid redundant -Wzero-as-null-pointer-constant warnings at
12769 the call sites. */
12770 if (TYPE_PTR_OR_PTRMEM_P (decl_type)
12771 && null_ptr_cst_p (arg))
12772 return nullptr_node;
12773
12774 /* [dcl.fct.default]
12775
12776 Local variables shall not be used in default argument
12777 expressions.
12778
12779 The keyword `this' shall not be used in a default argument of a
12780 member function. */
12781 var = cp_walk_tree_without_duplicates (&arg, local_variable_p_walkfn, NULL);
12782 if (var)
12783 {
12784 if (complain & tf_warning_or_error)
12785 {
12786 if (DECL_NAME (var) == this_identifier)
12787 permerror (input_location, "default argument %qE uses %qD",
12788 arg, var);
12789 else
12790 error ("default argument %qE uses local variable %qD", arg, var);
12791 }
12792 return error_mark_node;
12793 }
12794
12795 /* All is well. */
12796 return arg;
12797 }
12798
12799 /* Returns a deprecated type used within TYPE, or NULL_TREE if none. */
12800
12801 static tree
type_is_deprecated(tree type)12802 type_is_deprecated (tree type)
12803 {
12804 enum tree_code code;
12805 if (TREE_DEPRECATED (type))
12806 return type;
12807 if (TYPE_NAME (type))
12808 {
12809 if (TREE_DEPRECATED (TYPE_NAME (type)))
12810 return type;
12811 else
12812 return NULL_TREE;
12813 }
12814
12815 /* Do warn about using typedefs to a deprecated class. */
12816 if (OVERLOAD_TYPE_P (type) && type != TYPE_MAIN_VARIANT (type))
12817 return type_is_deprecated (TYPE_MAIN_VARIANT (type));
12818
12819 code = TREE_CODE (type);
12820
12821 if (code == POINTER_TYPE || code == REFERENCE_TYPE
12822 || code == OFFSET_TYPE || code == FUNCTION_TYPE
12823 || code == METHOD_TYPE || code == ARRAY_TYPE)
12824 return type_is_deprecated (TREE_TYPE (type));
12825
12826 if (TYPE_PTRMEMFUNC_P (type))
12827 return type_is_deprecated
12828 (TREE_TYPE (TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (type))));
12829
12830 return NULL_TREE;
12831 }
12832
12833 /* Decode the list of parameter types for a function type.
12834 Given the list of things declared inside the parens,
12835 return a list of types.
12836
12837 If this parameter does not end with an ellipsis, we append
12838 void_list_node.
12839
12840 *PARMS is set to the chain of PARM_DECLs created. */
12841
12842 tree
grokparms(tree parmlist,tree * parms)12843 grokparms (tree parmlist, tree *parms)
12844 {
12845 tree result = NULL_TREE;
12846 tree decls = NULL_TREE;
12847 tree parm;
12848 int any_error = 0;
12849
12850 for (parm = parmlist; parm != NULL_TREE; parm = TREE_CHAIN (parm))
12851 {
12852 tree type = NULL_TREE;
12853 tree init = TREE_PURPOSE (parm);
12854 tree decl = TREE_VALUE (parm);
12855
12856 if (parm == void_list_node)
12857 break;
12858
12859 if (! decl || TREE_TYPE (decl) == error_mark_node)
12860 continue;
12861
12862 type = TREE_TYPE (decl);
12863 if (VOID_TYPE_P (type))
12864 {
12865 if (same_type_p (type, void_type_node)
12866 && !init
12867 && !DECL_NAME (decl) && !result
12868 && TREE_CHAIN (parm) == void_list_node)
12869 /* DR 577: A parameter list consisting of a single
12870 unnamed parameter of non-dependent type 'void'. */
12871 break;
12872 else if (cv_qualified_p (type))
12873 error_at (DECL_SOURCE_LOCATION (decl),
12874 "invalid use of cv-qualified type %qT in "
12875 "parameter declaration", type);
12876 else
12877 error_at (DECL_SOURCE_LOCATION (decl),
12878 "invalid use of type %<void%> in parameter "
12879 "declaration");
12880 /* It's not a good idea to actually create parameters of
12881 type `void'; other parts of the compiler assume that a
12882 void type terminates the parameter list. */
12883 type = error_mark_node;
12884 TREE_TYPE (decl) = error_mark_node;
12885 }
12886
12887 if (type != error_mark_node)
12888 {
12889 if (deprecated_state != DEPRECATED_SUPPRESS)
12890 {
12891 tree deptype = type_is_deprecated (type);
12892 if (deptype)
12893 cp_warn_deprecated_use (deptype);
12894 }
12895
12896 /* Top-level qualifiers on the parameters are
12897 ignored for function types. */
12898 type = cp_build_qualified_type (type, 0);
12899 if (TREE_CODE (type) == METHOD_TYPE)
12900 {
12901 error ("parameter %qD invalidly declared method type", decl);
12902 type = build_pointer_type (type);
12903 TREE_TYPE (decl) = type;
12904 }
12905 else if (abstract_virtuals_error (decl, type))
12906 any_error = 1; /* Seems like a good idea. */
12907 else if (cxx_dialect < cxx17 && POINTER_TYPE_P (type))
12908 {
12909 /* Before C++17 DR 393:
12910 [dcl.fct]/6, parameter types cannot contain pointers
12911 (references) to arrays of unknown bound. */
12912 tree t = TREE_TYPE (type);
12913 int ptr = TYPE_PTR_P (type);
12914
12915 while (1)
12916 {
12917 if (TYPE_PTR_P (t))
12918 ptr = 1;
12919 else if (TREE_CODE (t) != ARRAY_TYPE)
12920 break;
12921 else if (!TYPE_DOMAIN (t))
12922 break;
12923 t = TREE_TYPE (t);
12924 }
12925 if (TREE_CODE (t) == ARRAY_TYPE)
12926 pedwarn (DECL_SOURCE_LOCATION (decl), OPT_Wpedantic,
12927 ptr
12928 ? G_("parameter %qD includes pointer to array of "
12929 "unknown bound %qT")
12930 : G_("parameter %qD includes reference to array of "
12931 "unknown bound %qT"),
12932 decl, t);
12933 }
12934
12935 if (any_error)
12936 init = NULL_TREE;
12937 else if (init && !processing_template_decl)
12938 init = check_default_argument (decl, init, tf_warning_or_error);
12939 }
12940
12941 DECL_CHAIN (decl) = decls;
12942 decls = decl;
12943 result = tree_cons (init, type, result);
12944 }
12945 decls = nreverse (decls);
12946 result = nreverse (result);
12947 if (parm)
12948 result = chainon (result, void_list_node);
12949 *parms = decls;
12950
12951 return result;
12952 }
12953
12954
12955 /* D is a constructor or overloaded `operator='.
12956
12957 Let T be the class in which D is declared. Then, this function
12958 returns:
12959
12960 -1 if D's is an ill-formed constructor or copy assignment operator
12961 whose first parameter is of type `T'.
12962 0 if D is not a copy constructor or copy assignment
12963 operator.
12964 1 if D is a copy constructor or copy assignment operator whose
12965 first parameter is a reference to non-const qualified T.
12966 2 if D is a copy constructor or copy assignment operator whose
12967 first parameter is a reference to const qualified T.
12968
12969 This function can be used as a predicate. Positive values indicate
12970 a copy constructor and nonzero values indicate a copy assignment
12971 operator. */
12972
12973 int
copy_fn_p(const_tree d)12974 copy_fn_p (const_tree d)
12975 {
12976 tree args;
12977 tree arg_type;
12978 int result = 1;
12979
12980 gcc_assert (DECL_FUNCTION_MEMBER_P (d));
12981
12982 if (TREE_CODE (d) == TEMPLATE_DECL
12983 || (DECL_TEMPLATE_INFO (d)
12984 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (d))))
12985 /* Instantiations of template member functions are never copy
12986 functions. Note that member functions of templated classes are
12987 represented as template functions internally, and we must
12988 accept those as copy functions. */
12989 return 0;
12990
12991 args = FUNCTION_FIRST_USER_PARMTYPE (d);
12992 if (!args)
12993 return 0;
12994
12995 arg_type = TREE_VALUE (args);
12996 if (arg_type == error_mark_node)
12997 return 0;
12998
12999 if (TYPE_MAIN_VARIANT (arg_type) == DECL_CONTEXT (d))
13000 {
13001 /* Pass by value copy assignment operator. */
13002 result = -1;
13003 }
13004 else if (TREE_CODE (arg_type) == REFERENCE_TYPE
13005 && !TYPE_REF_IS_RVALUE (arg_type)
13006 && TYPE_MAIN_VARIANT (TREE_TYPE (arg_type)) == DECL_CONTEXT (d))
13007 {
13008 if (CP_TYPE_CONST_P (TREE_TYPE (arg_type)))
13009 result = 2;
13010 }
13011 else
13012 return 0;
13013
13014 args = TREE_CHAIN (args);
13015
13016 if (args && args != void_list_node && !TREE_PURPOSE (args))
13017 /* There are more non-optional args. */
13018 return 0;
13019
13020 return result;
13021 }
13022
13023 /* D is a constructor or overloaded `operator='.
13024
13025 Let T be the class in which D is declared. Then, this function
13026 returns true when D is a move constructor or move assignment
13027 operator, false otherwise. */
13028
13029 bool
move_fn_p(const_tree d)13030 move_fn_p (const_tree d)
13031 {
13032 gcc_assert (DECL_FUNCTION_MEMBER_P (d));
13033
13034 if (cxx_dialect == cxx98)
13035 /* There are no move constructors if we are in C++98 mode. */
13036 return false;
13037
13038 if (TREE_CODE (d) == TEMPLATE_DECL
13039 || (DECL_TEMPLATE_INFO (d)
13040 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (d))))
13041 /* Instantiations of template member functions are never move
13042 functions. Note that member functions of templated classes are
13043 represented as template functions internally, and we must
13044 accept those as move functions. */
13045 return 0;
13046
13047 return move_signature_fn_p (d);
13048 }
13049
13050 /* D is a constructor or overloaded `operator='.
13051
13052 Then, this function returns true when D has the same signature as a move
13053 constructor or move assignment operator (because either it is such a
13054 ctor/op= or it is a template specialization with the same signature),
13055 false otherwise. */
13056
13057 bool
move_signature_fn_p(const_tree d)13058 move_signature_fn_p (const_tree d)
13059 {
13060 tree args;
13061 tree arg_type;
13062 bool result = false;
13063
13064 args = FUNCTION_FIRST_USER_PARMTYPE (d);
13065 if (!args)
13066 return 0;
13067
13068 arg_type = TREE_VALUE (args);
13069 if (arg_type == error_mark_node)
13070 return 0;
13071
13072 if (TREE_CODE (arg_type) == REFERENCE_TYPE
13073 && TYPE_REF_IS_RVALUE (arg_type)
13074 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (arg_type)),
13075 DECL_CONTEXT (d)))
13076 result = true;
13077
13078 args = TREE_CHAIN (args);
13079
13080 if (args && args != void_list_node && !TREE_PURPOSE (args))
13081 /* There are more non-optional args. */
13082 return false;
13083
13084 return result;
13085 }
13086
13087 /* Remember any special properties of member function DECL. */
13088
13089 void
grok_special_member_properties(tree decl)13090 grok_special_member_properties (tree decl)
13091 {
13092 tree class_type;
13093
13094 if (!DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
13095 return;
13096
13097 class_type = DECL_CONTEXT (decl);
13098 if (IDENTIFIER_CTOR_P (DECL_NAME (decl)))
13099 {
13100 int ctor = copy_fn_p (decl);
13101
13102 if (!DECL_ARTIFICIAL (decl))
13103 TYPE_HAS_USER_CONSTRUCTOR (class_type) = 1;
13104
13105 if (ctor > 0)
13106 {
13107 /* [class.copy]
13108
13109 A non-template constructor for class X is a copy
13110 constructor if its first parameter is of type X&, const
13111 X&, volatile X& or const volatile X&, and either there
13112 are no other parameters or else all other parameters have
13113 default arguments. */
13114 TYPE_HAS_COPY_CTOR (class_type) = 1;
13115 if (user_provided_p (decl))
13116 TYPE_HAS_COMPLEX_COPY_CTOR (class_type) = 1;
13117 if (ctor > 1)
13118 TYPE_HAS_CONST_COPY_CTOR (class_type) = 1;
13119 }
13120 else if (sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (decl)))
13121 TYPE_HAS_DEFAULT_CONSTRUCTOR (class_type) = 1;
13122 else if (move_fn_p (decl) && user_provided_p (decl))
13123 TYPE_HAS_COMPLEX_MOVE_CTOR (class_type) = 1;
13124 else if (is_list_ctor (decl))
13125 TYPE_HAS_LIST_CTOR (class_type) = 1;
13126
13127 if (DECL_DECLARED_CONSTEXPR_P (decl)
13128 && !ctor && !move_fn_p (decl))
13129 TYPE_HAS_CONSTEXPR_CTOR (class_type) = 1;
13130 }
13131 else if (DECL_NAME (decl) == assign_op_identifier)
13132 {
13133 /* [class.copy]
13134
13135 A non-template assignment operator for class X is a copy
13136 assignment operator if its parameter is of type X, X&, const
13137 X&, volatile X& or const volatile X&. */
13138
13139 int assop = copy_fn_p (decl);
13140
13141 if (assop)
13142 {
13143 TYPE_HAS_COPY_ASSIGN (class_type) = 1;
13144 if (user_provided_p (decl))
13145 TYPE_HAS_COMPLEX_COPY_ASSIGN (class_type) = 1;
13146 if (assop != 1)
13147 TYPE_HAS_CONST_COPY_ASSIGN (class_type) = 1;
13148 }
13149 else if (move_fn_p (decl) && user_provided_p (decl))
13150 TYPE_HAS_COMPLEX_MOVE_ASSIGN (class_type) = 1;
13151 }
13152 else if (IDENTIFIER_CONV_OP_P (DECL_NAME (decl)))
13153 TYPE_HAS_CONVERSION (class_type) = true;
13154
13155 /* Destructors are handled in check_methods. */
13156 }
13157
13158 /* Check a constructor DECL has the correct form. Complains
13159 if the class has a constructor of the form X(X). */
13160
13161 bool
grok_ctor_properties(const_tree ctype,const_tree decl)13162 grok_ctor_properties (const_tree ctype, const_tree decl)
13163 {
13164 int ctor_parm = copy_fn_p (decl);
13165
13166 if (ctor_parm < 0)
13167 {
13168 /* [class.copy]
13169
13170 A declaration of a constructor for a class X is ill-formed if
13171 its first parameter is of type (optionally cv-qualified) X
13172 and either there are no other parameters or else all other
13173 parameters have default arguments.
13174
13175 We *don't* complain about member template instantiations that
13176 have this form, though; they can occur as we try to decide
13177 what constructor to use during overload resolution. Since
13178 overload resolution will never prefer such a constructor to
13179 the non-template copy constructor (which is either explicitly
13180 or implicitly defined), there's no need to worry about their
13181 existence. Theoretically, they should never even be
13182 instantiated, but that's hard to forestall. */
13183 error ("invalid constructor; you probably meant %<%T (const %T&)%>",
13184 ctype, ctype);
13185 return false;
13186 }
13187
13188 return true;
13189 }
13190
13191 /* DECL is a declaration for an overloaded or conversion operator. If
13192 COMPLAIN is true, errors are issued for invalid declarations. */
13193
13194 bool
grok_op_properties(tree decl,bool complain)13195 grok_op_properties (tree decl, bool complain)
13196 {
13197 tree argtypes = TYPE_ARG_TYPES (TREE_TYPE (decl));
13198 bool methodp = TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE;
13199 tree name = DECL_NAME (decl);
13200
13201 tree class_type = DECL_CONTEXT (decl);
13202 if (class_type && !CLASS_TYPE_P (class_type))
13203 class_type = NULL_TREE;
13204
13205 tree_code operator_code;
13206 unsigned op_flags;
13207 if (IDENTIFIER_CONV_OP_P (name))
13208 {
13209 /* Conversion operators are TYPE_EXPR for the purposes of this
13210 function. */
13211 operator_code = TYPE_EXPR;
13212 op_flags = OVL_OP_FLAG_UNARY;
13213 }
13214 else
13215 {
13216 const ovl_op_info_t *ovl_op = IDENTIFIER_OVL_OP_INFO (name);
13217
13218 operator_code = ovl_op->tree_code;
13219 op_flags = ovl_op->flags;
13220 gcc_checking_assert (operator_code != ERROR_MARK);
13221 DECL_OVERLOADED_OPERATOR_CODE_RAW (decl) = ovl_op->ovl_op_code;
13222 }
13223
13224 if (op_flags & OVL_OP_FLAG_ALLOC)
13225 {
13226 /* operator new and operator delete are quite special. */
13227 if (class_type)
13228 switch (op_flags)
13229 {
13230 case OVL_OP_FLAG_ALLOC:
13231 TYPE_HAS_NEW_OPERATOR (class_type) = 1;
13232 break;
13233
13234 case OVL_OP_FLAG_ALLOC | OVL_OP_FLAG_DELETE:
13235 TYPE_GETS_DELETE (class_type) |= 1;
13236 break;
13237
13238 case OVL_OP_FLAG_ALLOC | OVL_OP_FLAG_VEC:
13239 TYPE_HAS_ARRAY_NEW_OPERATOR (class_type) = 1;
13240 break;
13241
13242 case OVL_OP_FLAG_ALLOC | OVL_OP_FLAG_DELETE | OVL_OP_FLAG_VEC:
13243 TYPE_GETS_DELETE (class_type) |= 2;
13244 break;
13245
13246 default:
13247 gcc_unreachable ();
13248 }
13249
13250 /* [basic.std.dynamic.allocation]/1:
13251
13252 A program is ill-formed if an allocation function is declared
13253 in a namespace scope other than global scope or declared
13254 static in global scope.
13255
13256 The same also holds true for deallocation functions. */
13257 if (DECL_NAMESPACE_SCOPE_P (decl))
13258 {
13259 if (CP_DECL_CONTEXT (decl) != global_namespace)
13260 {
13261 error ("%qD may not be declared within a namespace", decl);
13262 return false;
13263 }
13264
13265 if (!TREE_PUBLIC (decl))
13266 {
13267 error ("%qD may not be declared as static", decl);
13268 return false;
13269 }
13270 }
13271
13272 if (op_flags & OVL_OP_FLAG_DELETE)
13273 TREE_TYPE (decl) = coerce_delete_type (TREE_TYPE (decl));
13274 else
13275 {
13276 DECL_IS_OPERATOR_NEW (decl) = 1;
13277 TREE_TYPE (decl) = coerce_new_type (TREE_TYPE (decl));
13278 }
13279
13280 return true;
13281 }
13282
13283 /* An operator function must either be a non-static member function
13284 or have at least one parameter of a class, a reference to a class,
13285 an enumeration, or a reference to an enumeration. 13.4.0.6 */
13286 if (! methodp || DECL_STATIC_FUNCTION_P (decl))
13287 {
13288 if (operator_code == TYPE_EXPR
13289 || operator_code == CALL_EXPR
13290 || operator_code == COMPONENT_REF
13291 || operator_code == ARRAY_REF
13292 || operator_code == NOP_EXPR)
13293 {
13294 error ("%qD must be a nonstatic member function", decl);
13295 return false;
13296 }
13297
13298 if (DECL_STATIC_FUNCTION_P (decl))
13299 {
13300 error ("%qD must be either a non-static member "
13301 "function or a non-member function", decl);
13302 return false;
13303 }
13304
13305 for (tree arg = argtypes; ; arg = TREE_CHAIN (arg))
13306 {
13307 if (!arg || arg == void_list_node)
13308 {
13309 if (complain)
13310 error ("%qD must have an argument of class or "
13311 "enumerated type", decl);
13312 return false;
13313 }
13314
13315 tree type = non_reference (TREE_VALUE (arg));
13316 if (type == error_mark_node)
13317 return false;
13318
13319 /* MAYBE_CLASS_TYPE_P, rather than CLASS_TYPE_P, is used
13320 because these checks are performed even on template
13321 functions. */
13322 if (MAYBE_CLASS_TYPE_P (type)
13323 || TREE_CODE (type) == ENUMERAL_TYPE)
13324 break;
13325 }
13326 }
13327
13328 if (operator_code == CALL_EXPR)
13329 /* There are no further restrictions on the arguments to an overloaded
13330 "operator ()". */
13331 return true;
13332
13333 if (operator_code == COND_EXPR)
13334 {
13335 /* 13.4.0.3 */
13336 error ("ISO C++ prohibits overloading operator ?:");
13337 return false;
13338 }
13339
13340 /* Count the number of arguments and check for ellipsis. */
13341 int arity = 0;
13342 for (tree arg = argtypes; arg != void_list_node; arg = TREE_CHAIN (arg))
13343 {
13344 if (!arg)
13345 {
13346 /* Variadic. */
13347 error ("%qD must not have variable number of arguments", decl);
13348 return false;
13349 }
13350 ++arity;
13351 }
13352
13353 /* Verify correct number of arguments. */
13354 switch (op_flags)
13355 {
13356 case OVL_OP_FLAG_AMBIARY:
13357 if (arity == 1)
13358 {
13359 /* We have a unary instance of an ambi-ary op. Remap to the
13360 unary one. */
13361 unsigned alt = ovl_op_alternate[ovl_op_mapping [operator_code]];
13362 const ovl_op_info_t *ovl_op = &ovl_op_info[false][alt];
13363 gcc_checking_assert (ovl_op->flags == OVL_OP_FLAG_UNARY);
13364 operator_code = ovl_op->tree_code;
13365 DECL_OVERLOADED_OPERATOR_CODE_RAW (decl) = ovl_op->ovl_op_code;
13366 }
13367 else if (arity != 2)
13368 {
13369 /* This was an ambiguous operator but is invalid. */
13370 error (methodp
13371 ? G_("%qD must have either zero or one argument")
13372 : G_("%qD must have either one or two arguments"), decl);
13373 return false;
13374 }
13375 else if ((operator_code == POSTINCREMENT_EXPR
13376 || operator_code == POSTDECREMENT_EXPR)
13377 && ! processing_template_decl
13378 /* x++ and x--'s second argument must be an int. */
13379 && ! same_type_p (TREE_VALUE (TREE_CHAIN (argtypes)),
13380 integer_type_node))
13381 {
13382 error (methodp
13383 ? G_("postfix %qD must have %<int%> as its argument")
13384 : G_("postfix %qD must have %<int%> as its second argument"),
13385 decl);
13386 return false;
13387 }
13388 break;
13389
13390 case OVL_OP_FLAG_UNARY:
13391 if (arity != 1)
13392 {
13393 error (methodp
13394 ? G_("%qD must have no arguments")
13395 : G_("%qD must have exactly one argument"), decl);
13396 return false;
13397 }
13398 break;
13399
13400 case OVL_OP_FLAG_BINARY:
13401 if (arity != 2)
13402 {
13403 error (methodp
13404 ? G_("%qD must have exactly one argument")
13405 : G_("%qD must have exactly two arguments"), decl);
13406 return false;
13407 }
13408 break;
13409
13410 default:
13411 gcc_unreachable ();
13412 }
13413
13414 /* There can be no default arguments. */
13415 for (tree arg = argtypes; arg != void_list_node; arg = TREE_CHAIN (arg))
13416 if (TREE_PURPOSE (arg))
13417 {
13418 TREE_PURPOSE (arg) = NULL_TREE;
13419 if (operator_code == POSTINCREMENT_EXPR
13420 || operator_code == POSTDECREMENT_EXPR)
13421 pedwarn (input_location, OPT_Wpedantic,
13422 "%qD cannot have default arguments", decl);
13423 else
13424 {
13425 error ("%qD cannot have default arguments", decl);
13426 return false;
13427 }
13428 }
13429
13430 /* At this point the declaration is well-formed. It may not be
13431 sensible though. */
13432
13433 /* Check member function warnings only on the in-class declaration.
13434 There's no point warning on an out-of-class definition. */
13435 if (class_type && class_type != current_class_type)
13436 return true;
13437
13438 /* Warn about conversion operators that will never be used. */
13439 if (IDENTIFIER_CONV_OP_P (name)
13440 && ! DECL_TEMPLATE_INFO (decl)
13441 && warn_conversion)
13442 {
13443 tree t = TREE_TYPE (name);
13444 int ref = (TREE_CODE (t) == REFERENCE_TYPE);
13445
13446 if (ref)
13447 t = TYPE_MAIN_VARIANT (TREE_TYPE (t));
13448
13449 if (VOID_TYPE_P (t))
13450 warning (OPT_Wconversion,
13451 ref
13452 ? G_("conversion to a reference to void "
13453 "will never use a type conversion operator")
13454 : G_("conversion to void "
13455 "will never use a type conversion operator"));
13456 else if (class_type)
13457 {
13458 if (t == class_type)
13459 warning (OPT_Wconversion,
13460 ref
13461 ? G_("conversion to a reference to the same type "
13462 "will never use a type conversion operator")
13463 : G_("conversion to the same type "
13464 "will never use a type conversion operator"));
13465 /* Don't force t to be complete here. */
13466 else if (MAYBE_CLASS_TYPE_P (t)
13467 && COMPLETE_TYPE_P (t)
13468 && DERIVED_FROM_P (t, class_type))
13469 warning (OPT_Wconversion,
13470 ref
13471 ? G_("conversion to a reference to a base class "
13472 "will never use a type conversion operator")
13473 : G_("conversion to a base class "
13474 "will never use a type conversion operator"));
13475 }
13476 }
13477
13478 if (!warn_ecpp)
13479 return true;
13480
13481 /* Effective C++ rules below. */
13482
13483 /* More Effective C++ rule 7. */
13484 if (operator_code == TRUTH_ANDIF_EXPR
13485 || operator_code == TRUTH_ORIF_EXPR
13486 || operator_code == COMPOUND_EXPR)
13487 warning (OPT_Weffc__,
13488 "user-defined %qD always evaluates both arguments", decl);
13489
13490 /* More Effective C++ rule 6. */
13491 if (operator_code == POSTINCREMENT_EXPR
13492 || operator_code == POSTDECREMENT_EXPR
13493 || operator_code == PREINCREMENT_EXPR
13494 || operator_code == PREDECREMENT_EXPR)
13495 {
13496 tree arg = TREE_VALUE (argtypes);
13497 tree ret = TREE_TYPE (TREE_TYPE (decl));
13498 if (methodp || TREE_CODE (arg) == REFERENCE_TYPE)
13499 arg = TREE_TYPE (arg);
13500 arg = TYPE_MAIN_VARIANT (arg);
13501
13502 if (operator_code == PREINCREMENT_EXPR
13503 || operator_code == PREDECREMENT_EXPR)
13504 {
13505 if (TREE_CODE (ret) != REFERENCE_TYPE
13506 || !same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (ret)), arg))
13507 warning (OPT_Weffc__, "prefix %qD should return %qT", decl,
13508 build_reference_type (arg));
13509 }
13510 else
13511 {
13512 if (!same_type_p (TYPE_MAIN_VARIANT (ret), arg))
13513 warning (OPT_Weffc__, "postfix %qD should return %qT", decl, arg);
13514 }
13515 }
13516
13517 /* Effective C++ rule 23. */
13518 if (!DECL_ASSIGNMENT_OPERATOR_P (decl)
13519 && (operator_code == PLUS_EXPR
13520 || operator_code == MINUS_EXPR
13521 || operator_code == TRUNC_DIV_EXPR
13522 || operator_code == MULT_EXPR
13523 || operator_code == TRUNC_MOD_EXPR)
13524 && TREE_CODE (TREE_TYPE (TREE_TYPE (decl))) == REFERENCE_TYPE)
13525 warning (OPT_Weffc__, "%qD should return by value", decl);
13526
13527 return true;
13528 }
13529
13530 /* Return a string giving the keyword associate with CODE. */
13531
13532 static const char *
tag_name(enum tag_types code)13533 tag_name (enum tag_types code)
13534 {
13535 switch (code)
13536 {
13537 case record_type:
13538 return "struct";
13539 case class_type:
13540 return "class";
13541 case union_type:
13542 return "union";
13543 case enum_type:
13544 return "enum";
13545 case typename_type:
13546 return "typename";
13547 default:
13548 gcc_unreachable ();
13549 }
13550 }
13551
13552 /* Name lookup in an elaborated-type-specifier (after the keyword
13553 indicated by TAG_CODE) has found the TYPE_DECL DECL. If the
13554 elaborated-type-specifier is invalid, issue a diagnostic and return
13555 error_mark_node; otherwise, return the *_TYPE to which it referred.
13556 If ALLOW_TEMPLATE_P is true, TYPE may be a class template. */
13557
13558 tree
check_elaborated_type_specifier(enum tag_types tag_code,tree decl,bool allow_template_p)13559 check_elaborated_type_specifier (enum tag_types tag_code,
13560 tree decl,
13561 bool allow_template_p)
13562 {
13563 tree type;
13564
13565 /* In the case of:
13566
13567 struct S { struct S *p; };
13568
13569 name lookup will find the TYPE_DECL for the implicit "S::S"
13570 typedef. Adjust for that here. */
13571 if (DECL_SELF_REFERENCE_P (decl))
13572 decl = TYPE_NAME (TREE_TYPE (decl));
13573
13574 type = TREE_TYPE (decl);
13575
13576 /* Check TEMPLATE_TYPE_PARM first because DECL_IMPLICIT_TYPEDEF_P
13577 is false for this case as well. */
13578 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
13579 {
13580 error ("using template type parameter %qT after %qs",
13581 type, tag_name (tag_code));
13582 return error_mark_node;
13583 }
13584 /* Accept template template parameters. */
13585 else if (allow_template_p
13586 && (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM
13587 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM))
13588 ;
13589 /* [dcl.type.elab]
13590
13591 If the identifier resolves to a typedef-name or the
13592 simple-template-id resolves to an alias template
13593 specialization, the elaborated-type-specifier is ill-formed.
13594
13595 In other words, the only legitimate declaration to use in the
13596 elaborated type specifier is the implicit typedef created when
13597 the type is declared. */
13598 else if (!DECL_IMPLICIT_TYPEDEF_P (decl)
13599 && !DECL_SELF_REFERENCE_P (decl)
13600 && tag_code != typename_type)
13601 {
13602 if (alias_template_specialization_p (type))
13603 error ("using alias template specialization %qT after %qs",
13604 type, tag_name (tag_code));
13605 else
13606 error ("using typedef-name %qD after %qs", decl, tag_name (tag_code));
13607 inform (DECL_SOURCE_LOCATION (decl),
13608 "%qD has a previous declaration here", decl);
13609 return error_mark_node;
13610 }
13611 else if (TREE_CODE (type) != RECORD_TYPE
13612 && TREE_CODE (type) != UNION_TYPE
13613 && tag_code != enum_type
13614 && tag_code != typename_type)
13615 {
13616 error ("%qT referred to as %qs", type, tag_name (tag_code));
13617 inform (location_of (type), "%qT has a previous declaration here", type);
13618 return error_mark_node;
13619 }
13620 else if (TREE_CODE (type) != ENUMERAL_TYPE
13621 && tag_code == enum_type)
13622 {
13623 error ("%qT referred to as enum", type);
13624 inform (location_of (type), "%qT has a previous declaration here", type);
13625 return error_mark_node;
13626 }
13627 else if (!allow_template_p
13628 && TREE_CODE (type) == RECORD_TYPE
13629 && CLASSTYPE_IS_TEMPLATE (type))
13630 {
13631 /* If a class template appears as elaborated type specifier
13632 without a template header such as:
13633
13634 template <class T> class C {};
13635 void f(class C); // No template header here
13636
13637 then the required template argument is missing. */
13638 error ("template argument required for %<%s %T%>",
13639 tag_name (tag_code),
13640 DECL_NAME (CLASSTYPE_TI_TEMPLATE (type)));
13641 return error_mark_node;
13642 }
13643
13644 return type;
13645 }
13646
13647 /* Lookup NAME in elaborate type specifier in scope according to
13648 SCOPE and issue diagnostics if necessary.
13649 Return *_TYPE node upon success, NULL_TREE when the NAME is not
13650 found, and ERROR_MARK_NODE for type error. */
13651
13652 static tree
lookup_and_check_tag(enum tag_types tag_code,tree name,tag_scope scope,bool template_header_p)13653 lookup_and_check_tag (enum tag_types tag_code, tree name,
13654 tag_scope scope, bool template_header_p)
13655 {
13656 tree t;
13657 tree decl;
13658 if (scope == ts_global)
13659 {
13660 /* First try ordinary name lookup, ignoring hidden class name
13661 injected via friend declaration. */
13662 decl = lookup_name_prefer_type (name, 2);
13663 decl = strip_using_decl (decl);
13664 /* If that fails, the name will be placed in the smallest
13665 non-class, non-function-prototype scope according to 3.3.1/5.
13666 We may already have a hidden name declared as friend in this
13667 scope. So lookup again but not ignoring hidden names.
13668 If we find one, that name will be made visible rather than
13669 creating a new tag. */
13670 if (!decl)
13671 decl = lookup_type_scope (name, ts_within_enclosing_non_class);
13672 }
13673 else
13674 decl = lookup_type_scope (name, scope);
13675
13676 if (decl
13677 && (DECL_CLASS_TEMPLATE_P (decl)
13678 /* If scope is ts_current we're defining a class, so ignore a
13679 template template parameter. */
13680 || (scope != ts_current
13681 && DECL_TEMPLATE_TEMPLATE_PARM_P (decl))))
13682 decl = DECL_TEMPLATE_RESULT (decl);
13683
13684 if (decl && TREE_CODE (decl) == TYPE_DECL)
13685 {
13686 /* Look for invalid nested type:
13687 class C {
13688 class C {};
13689 }; */
13690 if (scope == ts_current && DECL_SELF_REFERENCE_P (decl))
13691 {
13692 error ("%qD has the same name as the class in which it is "
13693 "declared",
13694 decl);
13695 return error_mark_node;
13696 }
13697
13698 /* Two cases we need to consider when deciding if a class
13699 template is allowed as an elaborated type specifier:
13700 1. It is a self reference to its own class.
13701 2. It comes with a template header.
13702
13703 For example:
13704
13705 template <class T> class C {
13706 class C *c1; // DECL_SELF_REFERENCE_P is true
13707 class D;
13708 };
13709 template <class U> class C; // template_header_p is true
13710 template <class T> class C<T>::D {
13711 class C *c2; // DECL_SELF_REFERENCE_P is true
13712 }; */
13713
13714 t = check_elaborated_type_specifier (tag_code,
13715 decl,
13716 template_header_p
13717 | DECL_SELF_REFERENCE_P (decl));
13718 if (template_header_p && t && CLASS_TYPE_P (t)
13719 && (!CLASSTYPE_TEMPLATE_INFO (t)
13720 || (!PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t)))))
13721 {
13722 error ("%qT is not a template", t);
13723 inform (location_of (t), "previous declaration here");
13724 if (TYPE_CLASS_SCOPE_P (t)
13725 && CLASSTYPE_TEMPLATE_INFO (TYPE_CONTEXT (t)))
13726 inform (input_location,
13727 "perhaps you want to explicitly add %<%T::%>",
13728 TYPE_CONTEXT (t));
13729 t = error_mark_node;
13730 }
13731
13732 return t;
13733 }
13734 else if (decl && TREE_CODE (decl) == TREE_LIST)
13735 {
13736 error ("reference to %qD is ambiguous", name);
13737 print_candidates (decl);
13738 return error_mark_node;
13739 }
13740 else
13741 return NULL_TREE;
13742 }
13743
13744 /* Get the struct, enum or union (TAG_CODE says which) with tag NAME.
13745 Define the tag as a forward-reference if it is not defined.
13746
13747 If a declaration is given, process it here, and report an error if
13748 multiple declarations are not identical.
13749
13750 SCOPE is TS_CURRENT when this is also a definition. Only look in
13751 the current frame for the name (since C++ allows new names in any
13752 scope.) It is TS_WITHIN_ENCLOSING_NON_CLASS if this is a friend
13753 declaration. Only look beginning from the current scope outward up
13754 till the nearest non-class scope. Otherwise it is TS_GLOBAL.
13755
13756 TEMPLATE_HEADER_P is true when this declaration is preceded by
13757 a set of template parameters. */
13758
13759 static tree
xref_tag_1(enum tag_types tag_code,tree name,tag_scope scope,bool template_header_p)13760 xref_tag_1 (enum tag_types tag_code, tree name,
13761 tag_scope scope, bool template_header_p)
13762 {
13763 enum tree_code code;
13764 tree context = NULL_TREE;
13765
13766 gcc_assert (identifier_p (name));
13767
13768 switch (tag_code)
13769 {
13770 case record_type:
13771 case class_type:
13772 code = RECORD_TYPE;
13773 break;
13774 case union_type:
13775 code = UNION_TYPE;
13776 break;
13777 case enum_type:
13778 code = ENUMERAL_TYPE;
13779 break;
13780 default:
13781 gcc_unreachable ();
13782 }
13783
13784 /* In case of anonymous name, xref_tag is only called to
13785 make type node and push name. Name lookup is not required. */
13786 tree t = NULL_TREE;
13787 if (scope != ts_lambda && !anon_aggrname_p (name))
13788 t = lookup_and_check_tag (tag_code, name, scope, template_header_p);
13789
13790 if (t == error_mark_node)
13791 return error_mark_node;
13792
13793 if (scope != ts_current && t && current_class_type
13794 && template_class_depth (current_class_type)
13795 && template_header_p)
13796 {
13797 if (TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM)
13798 return t;
13799
13800 /* Since SCOPE is not TS_CURRENT, we are not looking at a
13801 definition of this tag. Since, in addition, we are currently
13802 processing a (member) template declaration of a template
13803 class, we must be very careful; consider:
13804
13805 template <class X> struct S1
13806
13807 template <class U> struct S2
13808 {
13809 template <class V> friend struct S1;
13810 };
13811
13812 Here, the S2::S1 declaration should not be confused with the
13813 outer declaration. In particular, the inner version should
13814 have a template parameter of level 2, not level 1.
13815
13816 On the other hand, when presented with:
13817
13818 template <class T> struct S1
13819 {
13820 template <class U> struct S2 {};
13821 template <class U> friend struct S2;
13822 };
13823
13824 the friend must find S1::S2 eventually. We accomplish this
13825 by making sure that the new type we create to represent this
13826 declaration has the right TYPE_CONTEXT. */
13827 context = TYPE_CONTEXT (t);
13828 t = NULL_TREE;
13829 }
13830
13831 if (! t)
13832 {
13833 /* If no such tag is yet defined, create a forward-reference node
13834 and record it as the "definition".
13835 When a real declaration of this type is found,
13836 the forward-reference will be altered into a real type. */
13837 if (code == ENUMERAL_TYPE)
13838 {
13839 error ("use of enum %q#D without previous declaration", name);
13840 return error_mark_node;
13841 }
13842 else
13843 {
13844 t = make_class_type (code);
13845 TYPE_CONTEXT (t) = context;
13846 if (scope == ts_lambda)
13847 {
13848 /* Mark it as a lambda type. */
13849 CLASSTYPE_LAMBDA_EXPR (t) = error_mark_node;
13850 /* And push it into current scope. */
13851 scope = ts_current;
13852 }
13853 t = pushtag (name, t, scope);
13854 }
13855 }
13856 else
13857 {
13858 if (template_header_p && MAYBE_CLASS_TYPE_P (t))
13859 {
13860 /* Check that we aren't trying to overload a class with different
13861 constraints. */
13862 tree constr = NULL_TREE;
13863 if (current_template_parms)
13864 {
13865 tree reqs = TEMPLATE_PARMS_CONSTRAINTS (current_template_parms);
13866 constr = build_constraints (reqs, NULL_TREE);
13867 }
13868 if (!redeclare_class_template (t, current_template_parms, constr))
13869 return error_mark_node;
13870 }
13871 else if (!processing_template_decl
13872 && CLASS_TYPE_P (t)
13873 && CLASSTYPE_IS_TEMPLATE (t))
13874 {
13875 error ("redeclaration of %qT as a non-template", t);
13876 inform (location_of (t), "previous declaration %qD", t);
13877 return error_mark_node;
13878 }
13879
13880 if (scope != ts_within_enclosing_non_class && TYPE_HIDDEN_P (t))
13881 {
13882 /* This is no longer an invisible friend. Make it
13883 visible. */
13884 tree decl = TYPE_NAME (t);
13885
13886 DECL_ANTICIPATED (decl) = false;
13887 DECL_FRIEND_P (decl) = false;
13888
13889 if (TYPE_TEMPLATE_INFO (t))
13890 {
13891 tree tmpl = TYPE_TI_TEMPLATE (t);
13892 DECL_ANTICIPATED (tmpl) = false;
13893 DECL_FRIEND_P (tmpl) = false;
13894 }
13895 }
13896 }
13897
13898 return t;
13899 }
13900
13901 /* Wrapper for xref_tag_1. */
13902
13903 tree
xref_tag(enum tag_types tag_code,tree name,tag_scope scope,bool template_header_p)13904 xref_tag (enum tag_types tag_code, tree name,
13905 tag_scope scope, bool template_header_p)
13906 {
13907 tree ret;
13908 bool subtime;
13909 subtime = timevar_cond_start (TV_NAME_LOOKUP);
13910 ret = xref_tag_1 (tag_code, name, scope, template_header_p);
13911 timevar_cond_stop (TV_NAME_LOOKUP, subtime);
13912 return ret;
13913 }
13914
13915
13916 tree
xref_tag_from_type(tree old,tree id,tag_scope scope)13917 xref_tag_from_type (tree old, tree id, tag_scope scope)
13918 {
13919 enum tag_types tag_kind;
13920
13921 if (TREE_CODE (old) == RECORD_TYPE)
13922 tag_kind = (CLASSTYPE_DECLARED_CLASS (old) ? class_type : record_type);
13923 else
13924 tag_kind = union_type;
13925
13926 if (id == NULL_TREE)
13927 id = TYPE_IDENTIFIER (old);
13928
13929 return xref_tag (tag_kind, id, scope, false);
13930 }
13931
13932 /* Create the binfo hierarchy for REF with (possibly NULL) base list
13933 BASE_LIST. For each element on BASE_LIST the TREE_PURPOSE is an
13934 access_* node, and the TREE_VALUE is the type of the base-class.
13935 Non-NULL TREE_TYPE indicates virtual inheritance. */
13936
13937 void
xref_basetypes(tree ref,tree base_list)13938 xref_basetypes (tree ref, tree base_list)
13939 {
13940 tree *basep;
13941 tree binfo, base_binfo;
13942 unsigned max_vbases = 0; /* Maximum direct & indirect virtual bases. */
13943 unsigned max_bases = 0; /* Maximum direct bases. */
13944 unsigned max_dvbases = 0; /* Maximum direct virtual bases. */
13945 int i;
13946 tree default_access;
13947 tree igo_prev; /* Track Inheritance Graph Order. */
13948
13949 if (ref == error_mark_node)
13950 return;
13951
13952 /* The base of a derived class is private by default, all others are
13953 public. */
13954 default_access = (TREE_CODE (ref) == RECORD_TYPE
13955 && CLASSTYPE_DECLARED_CLASS (ref)
13956 ? access_private_node : access_public_node);
13957
13958 /* First, make sure that any templates in base-classes are
13959 instantiated. This ensures that if we call ourselves recursively
13960 we do not get confused about which classes are marked and which
13961 are not. */
13962 basep = &base_list;
13963 while (*basep)
13964 {
13965 tree basetype = TREE_VALUE (*basep);
13966
13967 /* The dependent_type_p call below should really be dependent_scope_p
13968 so that we give a hard error about using an incomplete type as a
13969 base, but we allow it with a pedwarn for backward
13970 compatibility. */
13971 if (processing_template_decl
13972 && CLASS_TYPE_P (basetype) && TYPE_BEING_DEFINED (basetype))
13973 cxx_incomplete_type_diagnostic (NULL_TREE, basetype, DK_PEDWARN);
13974 if (!dependent_type_p (basetype)
13975 && !complete_type_or_else (basetype, NULL))
13976 /* An incomplete type. Remove it from the list. */
13977 *basep = TREE_CHAIN (*basep);
13978 else
13979 {
13980 max_bases++;
13981 if (TREE_TYPE (*basep))
13982 max_dvbases++;
13983 if (CLASS_TYPE_P (basetype))
13984 max_vbases += vec_safe_length (CLASSTYPE_VBASECLASSES (basetype));
13985 basep = &TREE_CHAIN (*basep);
13986 }
13987 }
13988 max_vbases += max_dvbases;
13989
13990 TYPE_MARKED_P (ref) = 1;
13991
13992 /* The binfo slot should be empty, unless this is an (ill-formed)
13993 redefinition. */
13994 gcc_assert (!TYPE_BINFO (ref) || TYPE_SIZE (ref));
13995
13996 gcc_assert (TYPE_MAIN_VARIANT (ref) == ref);
13997
13998 binfo = make_tree_binfo (max_bases);
13999
14000 TYPE_BINFO (ref) = binfo;
14001 BINFO_OFFSET (binfo) = size_zero_node;
14002 BINFO_TYPE (binfo) = ref;
14003
14004 /* Apply base-class info set up to the variants of this type. */
14005 fixup_type_variants (ref);
14006
14007 if (max_bases)
14008 {
14009 vec_alloc (BINFO_BASE_ACCESSES (binfo), max_bases);
14010 /* A C++98 POD cannot have base classes. */
14011 CLASSTYPE_NON_LAYOUT_POD_P (ref) = true;
14012
14013 if (TREE_CODE (ref) == UNION_TYPE)
14014 {
14015 error ("derived union %qT invalid", ref);
14016 return;
14017 }
14018 }
14019
14020 if (max_bases > 1)
14021 warning (OPT_Wmultiple_inheritance,
14022 "%qT defined with multiple direct bases", ref);
14023
14024 if (max_vbases)
14025 {
14026 /* An aggregate can't have virtual base classes. */
14027 CLASSTYPE_NON_AGGREGATE (ref) = true;
14028
14029 vec_alloc (CLASSTYPE_VBASECLASSES (ref), max_vbases);
14030
14031 if (max_dvbases)
14032 warning (OPT_Wvirtual_inheritance,
14033 "%qT defined with direct virtual base", ref);
14034 }
14035
14036 for (igo_prev = binfo; base_list; base_list = TREE_CHAIN (base_list))
14037 {
14038 tree access = TREE_PURPOSE (base_list);
14039 int via_virtual = TREE_TYPE (base_list) != NULL_TREE;
14040 tree basetype = TREE_VALUE (base_list);
14041
14042 if (access == access_default_node)
14043 access = default_access;
14044
14045 /* Before C++17, an aggregate cannot have base classes. In C++17, an
14046 aggregate can't have virtual, private, or protected base classes. */
14047 if (cxx_dialect < cxx17
14048 || access != access_public_node
14049 || via_virtual)
14050 CLASSTYPE_NON_AGGREGATE (ref) = true;
14051
14052 if (PACK_EXPANSION_P (basetype))
14053 basetype = PACK_EXPANSION_PATTERN (basetype);
14054 if (TREE_CODE (basetype) == TYPE_DECL)
14055 basetype = TREE_TYPE (basetype);
14056 if (!MAYBE_CLASS_TYPE_P (basetype) || TREE_CODE (basetype) == UNION_TYPE)
14057 {
14058 error ("base type %qT fails to be a struct or class type",
14059 basetype);
14060 goto dropped_base;
14061 }
14062
14063 base_binfo = NULL_TREE;
14064 if (CLASS_TYPE_P (basetype) && !dependent_scope_p (basetype))
14065 {
14066 base_binfo = TYPE_BINFO (basetype);
14067 /* The original basetype could have been a typedef'd type. */
14068 basetype = BINFO_TYPE (base_binfo);
14069
14070 /* Inherit flags from the base. */
14071 TYPE_HAS_NEW_OPERATOR (ref)
14072 |= TYPE_HAS_NEW_OPERATOR (basetype);
14073 TYPE_HAS_ARRAY_NEW_OPERATOR (ref)
14074 |= TYPE_HAS_ARRAY_NEW_OPERATOR (basetype);
14075 TYPE_GETS_DELETE (ref) |= TYPE_GETS_DELETE (basetype);
14076 TYPE_HAS_CONVERSION (ref) |= TYPE_HAS_CONVERSION (basetype);
14077 CLASSTYPE_DIAMOND_SHAPED_P (ref)
14078 |= CLASSTYPE_DIAMOND_SHAPED_P (basetype);
14079 CLASSTYPE_REPEATED_BASE_P (ref)
14080 |= CLASSTYPE_REPEATED_BASE_P (basetype);
14081 }
14082
14083 /* We must do this test after we've seen through a typedef
14084 type. */
14085 if (TYPE_MARKED_P (basetype))
14086 {
14087 if (basetype == ref)
14088 error ("recursive type %qT undefined", basetype);
14089 else
14090 error ("duplicate base type %qT invalid", basetype);
14091 goto dropped_base;
14092 }
14093
14094 if (PACK_EXPANSION_P (TREE_VALUE (base_list)))
14095 /* Regenerate the pack expansion for the bases. */
14096 basetype = make_pack_expansion (basetype);
14097
14098 TYPE_MARKED_P (basetype) = 1;
14099
14100 base_binfo = copy_binfo (base_binfo, basetype, ref,
14101 &igo_prev, via_virtual);
14102 if (!BINFO_INHERITANCE_CHAIN (base_binfo))
14103 BINFO_INHERITANCE_CHAIN (base_binfo) = binfo;
14104
14105 BINFO_BASE_APPEND (binfo, base_binfo);
14106 BINFO_BASE_ACCESS_APPEND (binfo, access);
14107 continue;
14108
14109 dropped_base:
14110 /* Update max_vbases to reflect the reality that we are dropping
14111 this base: if it reaches zero we want to undo the vec_alloc
14112 above to avoid inconsistencies during error-recovery: eg, in
14113 build_special_member_call, CLASSTYPE_VBASECLASSES non null
14114 and vtt null (c++/27952). */
14115 if (via_virtual)
14116 max_vbases--;
14117 if (CLASS_TYPE_P (basetype))
14118 max_vbases
14119 -= vec_safe_length (CLASSTYPE_VBASECLASSES (basetype));
14120 }
14121
14122 if (CLASSTYPE_VBASECLASSES (ref)
14123 && max_vbases == 0)
14124 vec_free (CLASSTYPE_VBASECLASSES (ref));
14125
14126 if (vec_safe_length (CLASSTYPE_VBASECLASSES (ref)) < max_vbases)
14127 /* If we didn't get max_vbases vbases, we must have shared at
14128 least one of them, and are therefore diamond shaped. */
14129 CLASSTYPE_DIAMOND_SHAPED_P (ref) = 1;
14130
14131 /* Unmark all the types. */
14132 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
14133 TYPE_MARKED_P (BINFO_TYPE (base_binfo)) = 0;
14134 TYPE_MARKED_P (ref) = 0;
14135
14136 /* Now see if we have a repeated base type. */
14137 if (!CLASSTYPE_REPEATED_BASE_P (ref))
14138 {
14139 for (base_binfo = binfo; base_binfo;
14140 base_binfo = TREE_CHAIN (base_binfo))
14141 {
14142 if (TYPE_MARKED_P (BINFO_TYPE (base_binfo)))
14143 {
14144 CLASSTYPE_REPEATED_BASE_P (ref) = 1;
14145 break;
14146 }
14147 TYPE_MARKED_P (BINFO_TYPE (base_binfo)) = 1;
14148 }
14149 for (base_binfo = binfo; base_binfo;
14150 base_binfo = TREE_CHAIN (base_binfo))
14151 if (TYPE_MARKED_P (BINFO_TYPE (base_binfo)))
14152 TYPE_MARKED_P (BINFO_TYPE (base_binfo)) = 0;
14153 else
14154 break;
14155 }
14156 }
14157
14158
14159 /* Copies the enum-related properties from type SRC to type DST.
14160 Used with the underlying type of an enum and the enum itself. */
14161 static void
copy_type_enum(tree dst,tree src)14162 copy_type_enum (tree dst, tree src)
14163 {
14164 tree t;
14165 for (t = dst; t; t = TYPE_NEXT_VARIANT (t))
14166 {
14167 TYPE_MIN_VALUE (t) = TYPE_MIN_VALUE (src);
14168 TYPE_MAX_VALUE (t) = TYPE_MAX_VALUE (src);
14169 TYPE_SIZE (t) = TYPE_SIZE (src);
14170 TYPE_SIZE_UNIT (t) = TYPE_SIZE_UNIT (src);
14171 SET_TYPE_MODE (dst, TYPE_MODE (src));
14172 TYPE_PRECISION (t) = TYPE_PRECISION (src);
14173 unsigned valign = TYPE_ALIGN (src);
14174 if (TYPE_USER_ALIGN (t))
14175 valign = MAX (valign, TYPE_ALIGN (t));
14176 else
14177 TYPE_USER_ALIGN (t) = TYPE_USER_ALIGN (src);
14178 SET_TYPE_ALIGN (t, valign);
14179 TYPE_UNSIGNED (t) = TYPE_UNSIGNED (src);
14180 }
14181 }
14182
14183 /* Begin compiling the definition of an enumeration type.
14184 NAME is its name,
14185
14186 if ENUMTYPE is not NULL_TREE then the type has alredy been found.
14187
14188 UNDERLYING_TYPE is the type that will be used as the storage for
14189 the enumeration type. This should be NULL_TREE if no storage type
14190 was specified.
14191
14192 ATTRIBUTES are any attributes specified after the enum-key.
14193
14194 SCOPED_ENUM_P is true if this is a scoped enumeration type.
14195
14196 if IS_NEW is not NULL, gets TRUE iff a new type is created.
14197
14198 Returns the type object, as yet incomplete.
14199 Also records info about it so that build_enumerator
14200 may be used to declare the individual values as they are read. */
14201
14202 tree
start_enum(tree name,tree enumtype,tree underlying_type,tree attributes,bool scoped_enum_p,bool * is_new)14203 start_enum (tree name, tree enumtype, tree underlying_type,
14204 tree attributes, bool scoped_enum_p, bool *is_new)
14205 {
14206 tree prevtype = NULL_TREE;
14207 gcc_assert (identifier_p (name));
14208
14209 if (is_new)
14210 *is_new = false;
14211 /* [C++0x dcl.enum]p5:
14212
14213 If not explicitly specified, the underlying type of a scoped
14214 enumeration type is int. */
14215 if (!underlying_type && scoped_enum_p)
14216 underlying_type = integer_type_node;
14217
14218 if (underlying_type)
14219 underlying_type = cv_unqualified (underlying_type);
14220
14221 /* If this is the real definition for a previous forward reference,
14222 fill in the contents in the same object that used to be the
14223 forward reference. */
14224 if (!enumtype)
14225 enumtype = lookup_and_check_tag (enum_type, name,
14226 /*tag_scope=*/ts_current,
14227 /*template_header_p=*/false);
14228
14229 /* In case of a template_decl, the only check that should be deferred
14230 to instantiation time is the comparison of underlying types. */
14231 if (enumtype && TREE_CODE (enumtype) == ENUMERAL_TYPE)
14232 {
14233 if (scoped_enum_p != SCOPED_ENUM_P (enumtype))
14234 {
14235 error_at (input_location, "scoped/unscoped mismatch "
14236 "in enum %q#T", enumtype);
14237 inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (enumtype)),
14238 "previous definition here");
14239 enumtype = error_mark_node;
14240 }
14241 else if (ENUM_FIXED_UNDERLYING_TYPE_P (enumtype) != !! underlying_type)
14242 {
14243 error_at (input_location, "underlying type mismatch "
14244 "in enum %q#T", enumtype);
14245 inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (enumtype)),
14246 "previous definition here");
14247 enumtype = error_mark_node;
14248 }
14249 else if (underlying_type && ENUM_UNDERLYING_TYPE (enumtype)
14250 && !dependent_type_p (underlying_type)
14251 && !dependent_type_p (ENUM_UNDERLYING_TYPE (enumtype))
14252 && !same_type_p (underlying_type,
14253 ENUM_UNDERLYING_TYPE (enumtype)))
14254 {
14255 error_at (input_location, "different underlying type "
14256 "in enum %q#T", enumtype);
14257 inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (enumtype)),
14258 "previous definition here");
14259 underlying_type = NULL_TREE;
14260 }
14261 }
14262
14263 if (!enumtype || TREE_CODE (enumtype) != ENUMERAL_TYPE
14264 || processing_template_decl)
14265 {
14266 /* In case of error, make a dummy enum to allow parsing to
14267 continue. */
14268 if (enumtype == error_mark_node)
14269 {
14270 name = make_anon_name ();
14271 enumtype = NULL_TREE;
14272 }
14273
14274 /* enumtype may be an ENUMERAL_TYPE if this is a redefinition
14275 of an opaque enum, or an opaque enum of an already defined
14276 enumeration (C++0x only).
14277 In any other case, it'll be NULL_TREE. */
14278 if (!enumtype)
14279 {
14280 if (is_new)
14281 *is_new = true;
14282 }
14283 prevtype = enumtype;
14284
14285 /* Do not push the decl more than once, unless we need to
14286 compare underlying types at instantiation time */
14287 if (!enumtype
14288 || TREE_CODE (enumtype) != ENUMERAL_TYPE
14289 || (underlying_type
14290 && dependent_type_p (underlying_type))
14291 || (ENUM_UNDERLYING_TYPE (enumtype)
14292 && dependent_type_p (ENUM_UNDERLYING_TYPE (enumtype))))
14293 {
14294 enumtype = cxx_make_type (ENUMERAL_TYPE);
14295 enumtype = pushtag (name, enumtype, /*tag_scope=*/ts_current);
14296
14297 /* std::byte aliases anything. */
14298 if (enumtype != error_mark_node
14299 && TYPE_CONTEXT (enumtype) == std_node
14300 && !strcmp ("byte", TYPE_NAME_STRING (enumtype)))
14301 TYPE_ALIAS_SET (enumtype) = 0;
14302 }
14303 else
14304 enumtype = xref_tag (enum_type, name, /*tag_scope=*/ts_current,
14305 false);
14306
14307 if (enumtype == error_mark_node)
14308 return error_mark_node;
14309
14310 /* The enum is considered opaque until the opening '{' of the
14311 enumerator list. */
14312 SET_OPAQUE_ENUM_P (enumtype, true);
14313 ENUM_FIXED_UNDERLYING_TYPE_P (enumtype) = !! underlying_type;
14314 }
14315
14316 SET_SCOPED_ENUM_P (enumtype, scoped_enum_p);
14317
14318 cplus_decl_attributes (&enumtype, attributes, (int)ATTR_FLAG_TYPE_IN_PLACE);
14319
14320 if (underlying_type)
14321 {
14322 if (ENUM_UNDERLYING_TYPE (enumtype))
14323 /* We already checked that it matches, don't change it to a different
14324 typedef variant. */;
14325 else if (CP_INTEGRAL_TYPE_P (underlying_type))
14326 {
14327 copy_type_enum (enumtype, underlying_type);
14328 ENUM_UNDERLYING_TYPE (enumtype) = underlying_type;
14329 }
14330 else if (dependent_type_p (underlying_type))
14331 ENUM_UNDERLYING_TYPE (enumtype) = underlying_type;
14332 else
14333 error ("underlying type %qT of %qT must be an integral type",
14334 underlying_type, enumtype);
14335 }
14336
14337 /* If into a template class, the returned enum is always the first
14338 declaration (opaque or not) seen. This way all the references to
14339 this type will be to the same declaration. The following ones are used
14340 only to check for definition errors. */
14341 if (prevtype && processing_template_decl)
14342 return prevtype;
14343 else
14344 return enumtype;
14345 }
14346
14347 /* After processing and defining all the values of an enumeration type,
14348 install their decls in the enumeration type.
14349 ENUMTYPE is the type object. */
14350
14351 void
finish_enum_value_list(tree enumtype)14352 finish_enum_value_list (tree enumtype)
14353 {
14354 tree values;
14355 tree underlying_type;
14356 tree decl;
14357 tree value;
14358 tree minnode, maxnode;
14359 tree t;
14360
14361 bool fixed_underlying_type_p
14362 = ENUM_UNDERLYING_TYPE (enumtype) != NULL_TREE;
14363
14364 /* We built up the VALUES in reverse order. */
14365 TYPE_VALUES (enumtype) = nreverse (TYPE_VALUES (enumtype));
14366
14367 /* For an enum defined in a template, just set the type of the values;
14368 all further processing is postponed until the template is
14369 instantiated. We need to set the type so that tsubst of a CONST_DECL
14370 works. */
14371 if (processing_template_decl)
14372 {
14373 for (values = TYPE_VALUES (enumtype);
14374 values;
14375 values = TREE_CHAIN (values))
14376 TREE_TYPE (TREE_VALUE (values)) = enumtype;
14377 return;
14378 }
14379
14380 /* Determine the minimum and maximum values of the enumerators. */
14381 if (TYPE_VALUES (enumtype))
14382 {
14383 minnode = maxnode = NULL_TREE;
14384
14385 for (values = TYPE_VALUES (enumtype);
14386 values;
14387 values = TREE_CHAIN (values))
14388 {
14389 decl = TREE_VALUE (values);
14390
14391 /* [dcl.enum]: Following the closing brace of an enum-specifier,
14392 each enumerator has the type of its enumeration. Prior to the
14393 closing brace, the type of each enumerator is the type of its
14394 initializing value. */
14395 TREE_TYPE (decl) = enumtype;
14396
14397 /* Update the minimum and maximum values, if appropriate. */
14398 value = DECL_INITIAL (decl);
14399 if (value == error_mark_node)
14400 value = integer_zero_node;
14401 /* Figure out what the minimum and maximum values of the
14402 enumerators are. */
14403 if (!minnode)
14404 minnode = maxnode = value;
14405 else if (tree_int_cst_lt (maxnode, value))
14406 maxnode = value;
14407 else if (tree_int_cst_lt (value, minnode))
14408 minnode = value;
14409 }
14410 }
14411 else
14412 /* [dcl.enum]
14413
14414 If the enumerator-list is empty, the underlying type is as if
14415 the enumeration had a single enumerator with value 0. */
14416 minnode = maxnode = integer_zero_node;
14417
14418 if (!fixed_underlying_type_p)
14419 {
14420 /* Compute the number of bits require to represent all values of the
14421 enumeration. We must do this before the type of MINNODE and
14422 MAXNODE are transformed, since tree_int_cst_min_precision relies
14423 on the TREE_TYPE of the value it is passed. */
14424 signop sgn = tree_int_cst_sgn (minnode) >= 0 ? UNSIGNED : SIGNED;
14425 int lowprec = tree_int_cst_min_precision (minnode, sgn);
14426 int highprec = tree_int_cst_min_precision (maxnode, sgn);
14427 int precision = MAX (lowprec, highprec);
14428 unsigned int itk;
14429 bool use_short_enum;
14430
14431 /* Determine the underlying type of the enumeration.
14432
14433 [dcl.enum]
14434
14435 The underlying type of an enumeration is an integral type that
14436 can represent all the enumerator values defined in the
14437 enumeration. It is implementation-defined which integral type is
14438 used as the underlying type for an enumeration except that the
14439 underlying type shall not be larger than int unless the value of
14440 an enumerator cannot fit in an int or unsigned int.
14441
14442 We use "int" or an "unsigned int" as the underlying type, even if
14443 a smaller integral type would work, unless the user has
14444 explicitly requested that we use the smallest possible type. The
14445 user can request that for all enumerations with a command line
14446 flag, or for just one enumeration with an attribute. */
14447
14448 use_short_enum = flag_short_enums
14449 || lookup_attribute ("packed", TYPE_ATTRIBUTES (enumtype));
14450
14451 /* If the precision of the type was specified with an attribute and it
14452 was too small, give an error. Otherwise, use it. */
14453 if (TYPE_PRECISION (enumtype))
14454 {
14455 if (precision > TYPE_PRECISION (enumtype))
14456 error ("specified mode too small for enumeral values");
14457 else
14458 {
14459 use_short_enum = true;
14460 precision = TYPE_PRECISION (enumtype);
14461 }
14462 }
14463
14464 for (itk = (use_short_enum ? itk_char : itk_int);
14465 itk != itk_none;
14466 itk++)
14467 {
14468 underlying_type = integer_types[itk];
14469 if (underlying_type != NULL_TREE
14470 && TYPE_PRECISION (underlying_type) >= precision
14471 && TYPE_SIGN (underlying_type) == sgn)
14472 break;
14473 }
14474 if (itk == itk_none)
14475 {
14476 /* DR 377
14477
14478 IF no integral type can represent all the enumerator values, the
14479 enumeration is ill-formed. */
14480 error ("no integral type can represent all of the enumerator values "
14481 "for %qT", enumtype);
14482 precision = TYPE_PRECISION (long_long_integer_type_node);
14483 underlying_type = integer_types[itk_unsigned_long_long];
14484 }
14485
14486 /* [dcl.enum]
14487
14488 The value of sizeof() applied to an enumeration type, an object
14489 of an enumeration type, or an enumerator, is the value of sizeof()
14490 applied to the underlying type. */
14491 copy_type_enum (enumtype, underlying_type);
14492
14493 /* Compute the minimum and maximum values for the type.
14494
14495 [dcl.enum]
14496
14497 For an enumeration where emin is the smallest enumerator and emax
14498 is the largest, the values of the enumeration are the values of the
14499 underlying type in the range bmin to bmax, where bmin and bmax are,
14500 respectively, the smallest and largest values of the smallest bit-
14501 field that can store emin and emax. */
14502
14503 /* The middle-end currently assumes that types with TYPE_PRECISION
14504 narrower than their underlying type are suitably zero or sign
14505 extended to fill their mode. Similarly, it assumes that the front
14506 end assures that a value of a particular type must be within
14507 TYPE_MIN_VALUE and TYPE_MAX_VALUE.
14508
14509 We used to set these fields based on bmin and bmax, but that led
14510 to invalid assumptions like optimizing away bounds checking. So
14511 now we just set the TYPE_PRECISION, TYPE_MIN_VALUE, and
14512 TYPE_MAX_VALUE to the values for the mode above and only restrict
14513 the ENUM_UNDERLYING_TYPE for the benefit of diagnostics. */
14514 ENUM_UNDERLYING_TYPE (enumtype)
14515 = build_distinct_type_copy (underlying_type);
14516 TYPE_PRECISION (ENUM_UNDERLYING_TYPE (enumtype)) = precision;
14517 set_min_and_max_values_for_integral_type
14518 (ENUM_UNDERLYING_TYPE (enumtype), precision, sgn);
14519
14520 /* If -fstrict-enums, still constrain TYPE_MIN/MAX_VALUE. */
14521 if (flag_strict_enums)
14522 set_min_and_max_values_for_integral_type (enumtype, precision, sgn);
14523 }
14524 else
14525 underlying_type = ENUM_UNDERLYING_TYPE (enumtype);
14526
14527 /* Convert each of the enumerators to the type of the underlying
14528 type of the enumeration. */
14529 for (values = TYPE_VALUES (enumtype); values; values = TREE_CHAIN (values))
14530 {
14531 location_t saved_location;
14532
14533 decl = TREE_VALUE (values);
14534 saved_location = input_location;
14535 input_location = DECL_SOURCE_LOCATION (decl);
14536 if (fixed_underlying_type_p)
14537 /* If the enumeration type has a fixed underlying type, we
14538 already checked all of the enumerator values. */
14539 value = DECL_INITIAL (decl);
14540 else
14541 value = perform_implicit_conversion (underlying_type,
14542 DECL_INITIAL (decl),
14543 tf_warning_or_error);
14544 input_location = saved_location;
14545
14546 /* Do not clobber shared ints. */
14547 if (value != error_mark_node)
14548 {
14549 value = copy_node (value);
14550
14551 TREE_TYPE (value) = enumtype;
14552 }
14553 DECL_INITIAL (decl) = value;
14554 }
14555
14556 /* Fix up all variant types of this enum type. */
14557 for (t = TYPE_MAIN_VARIANT (enumtype); t; t = TYPE_NEXT_VARIANT (t))
14558 TYPE_VALUES (t) = TYPE_VALUES (enumtype);
14559
14560 if (at_class_scope_p ()
14561 && COMPLETE_TYPE_P (current_class_type)
14562 && UNSCOPED_ENUM_P (enumtype))
14563 {
14564 insert_late_enum_def_bindings (current_class_type, enumtype);
14565 /* TYPE_FIELDS needs fixup. */
14566 fixup_type_variants (current_class_type);
14567 }
14568
14569 /* Finish debugging output for this type. */
14570 rest_of_type_compilation (enumtype, namespace_bindings_p ());
14571
14572 /* Each enumerator now has the type of its enumeration. Clear the cache
14573 so that this change in types doesn't confuse us later on. */
14574 clear_cv_and_fold_caches ();
14575 }
14576
14577 /* Finishes the enum type. This is called only the first time an
14578 enumeration is seen, be it opaque or odinary.
14579 ENUMTYPE is the type object. */
14580
14581 void
finish_enum(tree enumtype)14582 finish_enum (tree enumtype)
14583 {
14584 if (processing_template_decl)
14585 {
14586 if (at_function_scope_p ())
14587 add_stmt (build_min (TAG_DEFN, enumtype));
14588 return;
14589 }
14590
14591 /* If this is a forward declaration, there should not be any variants,
14592 though we can get a variant in the middle of an enum-specifier with
14593 wacky code like 'enum E { e = sizeof(const E*) };' */
14594 gcc_assert (enumtype == TYPE_MAIN_VARIANT (enumtype)
14595 && (TYPE_VALUES (enumtype)
14596 || !TYPE_NEXT_VARIANT (enumtype)));
14597 }
14598
14599 /* Build and install a CONST_DECL for an enumeration constant of the
14600 enumeration type ENUMTYPE whose NAME and VALUE (if any) are provided.
14601 Apply ATTRIBUTES if available. LOC is the location of NAME.
14602 Assignment of sequential values by default is handled here. */
14603
14604 void
build_enumerator(tree name,tree value,tree enumtype,tree attributes,location_t loc)14605 build_enumerator (tree name, tree value, tree enumtype, tree attributes,
14606 location_t loc)
14607 {
14608 tree decl;
14609 tree context;
14610 tree type;
14611
14612 /* scalar_constant_value will pull out this expression, so make sure
14613 it's folded as appropriate. */
14614 if (processing_template_decl)
14615 value = fold_non_dependent_expr (value);
14616
14617 /* If the VALUE was erroneous, pretend it wasn't there; that will
14618 result in the enum being assigned the next value in sequence. */
14619 if (value == error_mark_node)
14620 value = NULL_TREE;
14621
14622 /* Remove no-op casts from the value. */
14623 if (value)
14624 STRIP_TYPE_NOPS (value);
14625
14626 if (! processing_template_decl)
14627 {
14628 /* Validate and default VALUE. */
14629 if (value != NULL_TREE)
14630 {
14631 if (!ENUM_UNDERLYING_TYPE (enumtype))
14632 {
14633 tree tmp_value = build_expr_type_conversion (WANT_INT | WANT_ENUM,
14634 value, true);
14635 if (tmp_value)
14636 value = tmp_value;
14637 }
14638 else if (! INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P
14639 (TREE_TYPE (value)))
14640 value = perform_implicit_conversion_flags
14641 (ENUM_UNDERLYING_TYPE (enumtype), value, tf_warning_or_error,
14642 LOOKUP_IMPLICIT | LOOKUP_NO_NARROWING);
14643
14644 if (value == error_mark_node)
14645 value = NULL_TREE;
14646
14647 if (value != NULL_TREE)
14648 {
14649 if (! INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P
14650 (TREE_TYPE (value)))
14651 {
14652 error ("enumerator value for %qD must have integral or "
14653 "unscoped enumeration type", name);
14654 value = NULL_TREE;
14655 }
14656 else
14657 {
14658 value = cxx_constant_value (value);
14659
14660 if (TREE_CODE (value) != INTEGER_CST)
14661 {
14662 error ("enumerator value for %qD is not an integer "
14663 "constant", name);
14664 value = NULL_TREE;
14665 }
14666 }
14667 }
14668 }
14669
14670 /* Default based on previous value. */
14671 if (value == NULL_TREE)
14672 {
14673 if (TYPE_VALUES (enumtype))
14674 {
14675 tree prev_value;
14676 bool overflowed;
14677
14678 /* C++03 7.2/4: If no initializer is specified for the first
14679 enumerator, the type is an unspecified integral
14680 type. Otherwise the type is the same as the type of the
14681 initializing value of the preceding enumerator unless the
14682 incremented value is not representable in that type, in
14683 which case the type is an unspecified integral type
14684 sufficient to contain the incremented value. */
14685 prev_value = DECL_INITIAL (TREE_VALUE (TYPE_VALUES (enumtype)));
14686 if (error_operand_p (prev_value))
14687 value = error_mark_node;
14688 else
14689 {
14690 tree type = TREE_TYPE (prev_value);
14691 signop sgn = TYPE_SIGN (type);
14692 widest_int wi = wi::add (wi::to_widest (prev_value), 1, sgn,
14693 &overflowed);
14694 if (!overflowed)
14695 {
14696 bool pos = !wi::neg_p (wi, sgn);
14697 if (!wi::fits_to_tree_p (wi, type))
14698 {
14699 unsigned int itk;
14700 for (itk = itk_int; itk != itk_none; itk++)
14701 {
14702 type = integer_types[itk];
14703 if (type != NULL_TREE
14704 && (pos || !TYPE_UNSIGNED (type))
14705 && wi::fits_to_tree_p (wi, type))
14706 break;
14707 }
14708 if (type && cxx_dialect < cxx11
14709 && itk > itk_unsigned_long)
14710 pedwarn (input_location, OPT_Wlong_long,
14711 pos ? G_("\
14712 incremented enumerator value is too large for %<unsigned long%>") : G_("\
14713 incremented enumerator value is too large for %<long%>"));
14714 }
14715 if (type == NULL_TREE)
14716 overflowed = true;
14717 else
14718 value = wide_int_to_tree (type, wi);
14719 }
14720
14721 if (overflowed)
14722 {
14723 error ("overflow in enumeration values at %qD", name);
14724 value = error_mark_node;
14725 }
14726 }
14727 }
14728 else
14729 value = integer_zero_node;
14730 }
14731
14732 /* Remove no-op casts from the value. */
14733 STRIP_TYPE_NOPS (value);
14734
14735 /* If the underlying type of the enum is fixed, check whether
14736 the enumerator values fits in the underlying type. If it
14737 does not fit, the program is ill-formed [C++0x dcl.enum]. */
14738 if (ENUM_UNDERLYING_TYPE (enumtype)
14739 && value
14740 && TREE_CODE (value) == INTEGER_CST)
14741 {
14742 if (!int_fits_type_p (value, ENUM_UNDERLYING_TYPE (enumtype)))
14743 error ("enumerator value %qE is outside the range of underlying "
14744 "type %qT", value, ENUM_UNDERLYING_TYPE (enumtype));
14745
14746 /* Convert the value to the appropriate type. */
14747 value = fold_convert (ENUM_UNDERLYING_TYPE (enumtype), value);
14748 }
14749 }
14750
14751 /* C++ associates enums with global, function, or class declarations. */
14752 context = current_scope ();
14753
14754 /* Build the actual enumeration constant. Note that the enumeration
14755 constants have the underlying type of the enum (if it is fixed)
14756 or the type of their initializer (if the underlying type of the
14757 enum is not fixed):
14758
14759 [ C++0x dcl.enum ]
14760
14761 If the underlying type is fixed, the type of each enumerator
14762 prior to the closing brace is the underlying type; if the
14763 initializing value of an enumerator cannot be represented by
14764 the underlying type, the program is ill-formed. If the
14765 underlying type is not fixed, the type of each enumerator is
14766 the type of its initializing value.
14767
14768 If the underlying type is not fixed, it will be computed by
14769 finish_enum and we will reset the type of this enumerator. Of
14770 course, if we're processing a template, there may be no value. */
14771 type = value ? TREE_TYPE (value) : NULL_TREE;
14772
14773 decl = build_decl (loc, CONST_DECL, name, type);
14774
14775 DECL_CONTEXT (decl) = enumtype;
14776 TREE_CONSTANT (decl) = 1;
14777 TREE_READONLY (decl) = 1;
14778 DECL_INITIAL (decl) = value;
14779
14780 if (attributes)
14781 cplus_decl_attributes (&decl, attributes, 0);
14782
14783 if (context && context == current_class_type && !SCOPED_ENUM_P (enumtype))
14784 {
14785 /* In something like `struct S { enum E { i = 7 }; };' we put `i'
14786 on the TYPE_FIELDS list for `S'. (That's so that you can say
14787 things like `S::i' later.) */
14788
14789 /* The enumerator may be getting declared outside of its enclosing
14790 class, like so:
14791
14792 class S { public: enum E : int; }; enum S::E : int { i = 7; };
14793
14794 For which case we need to make sure that the access of `S::i'
14795 matches the access of `S::E'. */
14796 tree saved_cas = current_access_specifier;
14797 if (TREE_PRIVATE (TYPE_NAME (enumtype)))
14798 current_access_specifier = access_private_node;
14799 else if (TREE_PROTECTED (TYPE_NAME (enumtype)))
14800 current_access_specifier = access_protected_node;
14801 else
14802 current_access_specifier = access_public_node;
14803
14804 finish_member_declaration (decl);
14805
14806 current_access_specifier = saved_cas;
14807 }
14808 else
14809 pushdecl (decl);
14810
14811 /* Add this enumeration constant to the list for this type. */
14812 TYPE_VALUES (enumtype) = tree_cons (name, decl, TYPE_VALUES (enumtype));
14813 }
14814
14815 /* Look for an enumerator with the given NAME within the enumeration
14816 type ENUMTYPE. This routine is used primarily for qualified name
14817 lookup into an enumerator in C++0x, e.g.,
14818
14819 enum class Color { Red, Green, Blue };
14820
14821 Color color = Color::Red;
14822
14823 Returns the value corresponding to the enumerator, or
14824 NULL_TREE if no such enumerator was found. */
14825 tree
lookup_enumerator(tree enumtype,tree name)14826 lookup_enumerator (tree enumtype, tree name)
14827 {
14828 tree e;
14829 gcc_assert (enumtype && TREE_CODE (enumtype) == ENUMERAL_TYPE);
14830
14831 e = purpose_member (name, TYPE_VALUES (enumtype));
14832 return e? TREE_VALUE (e) : NULL_TREE;
14833 }
14834
14835
14836 /* We're defining DECL. Make sure that its type is OK. */
14837
14838 static void
check_function_type(tree decl,tree current_function_parms)14839 check_function_type (tree decl, tree current_function_parms)
14840 {
14841 tree fntype = TREE_TYPE (decl);
14842 tree return_type = complete_type (TREE_TYPE (fntype));
14843
14844 /* In a function definition, arg types must be complete. */
14845 require_complete_types_for_parms (current_function_parms);
14846
14847 if (dependent_type_p (return_type)
14848 || type_uses_auto (return_type))
14849 return;
14850 if (!COMPLETE_OR_VOID_TYPE_P (return_type))
14851 {
14852 tree args = TYPE_ARG_TYPES (fntype);
14853
14854 error ("return type %q#T is incomplete", return_type);
14855
14856 /* Make it return void instead. */
14857 if (TREE_CODE (fntype) == METHOD_TYPE)
14858 fntype = build_method_type_directly (TREE_TYPE (TREE_VALUE (args)),
14859 void_type_node,
14860 TREE_CHAIN (args));
14861 else
14862 fntype = build_function_type (void_type_node, args);
14863 fntype
14864 = build_exception_variant (fntype,
14865 TYPE_RAISES_EXCEPTIONS (TREE_TYPE (decl)));
14866 fntype = (cp_build_type_attribute_variant
14867 (fntype, TYPE_ATTRIBUTES (TREE_TYPE (decl))));
14868 TREE_TYPE (decl) = fntype;
14869 }
14870 else
14871 {
14872 abstract_virtuals_error (decl, TREE_TYPE (fntype));
14873 maybe_warn_parm_abi (TREE_TYPE (fntype),
14874 DECL_SOURCE_LOCATION (decl));
14875 }
14876 }
14877
14878 /* True iff FN is an implicitly-defined default constructor. */
14879
14880 static bool
implicit_default_ctor_p(tree fn)14881 implicit_default_ctor_p (tree fn)
14882 {
14883 return (DECL_CONSTRUCTOR_P (fn)
14884 && !user_provided_p (fn)
14885 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)));
14886 }
14887
14888 /* Clobber the contents of *this to let the back end know that the object
14889 storage is dead when we enter the constructor or leave the destructor. */
14890
14891 static tree
build_clobber_this()14892 build_clobber_this ()
14893 {
14894 /* Clobbering an empty base is pointless, and harmful if its one byte
14895 TYPE_SIZE overlays real data. */
14896 if (is_empty_class (current_class_type))
14897 return void_node;
14898
14899 /* If we have virtual bases, clobber the whole object, but only if we're in
14900 charge. If we don't have virtual bases, clobber the as-base type so we
14901 don't mess with tail padding. */
14902 bool vbases = CLASSTYPE_VBASECLASSES (current_class_type);
14903
14904 tree ctype = current_class_type;
14905 if (!vbases)
14906 ctype = CLASSTYPE_AS_BASE (ctype);
14907
14908 tree clobber = build_constructor (ctype, NULL);
14909 TREE_THIS_VOLATILE (clobber) = true;
14910
14911 tree thisref = current_class_ref;
14912 if (ctype != current_class_type)
14913 {
14914 thisref = build_nop (build_reference_type (ctype), current_class_ptr);
14915 thisref = convert_from_reference (thisref);
14916 }
14917
14918 tree exprstmt = build2 (MODIFY_EXPR, void_type_node, thisref, clobber);
14919 if (vbases)
14920 exprstmt = build_if_in_charge (exprstmt);
14921
14922 return exprstmt;
14923 }
14924
14925 /* Create the FUNCTION_DECL for a function definition.
14926 DECLSPECS and DECLARATOR are the parts of the declaration;
14927 they describe the function's name and the type it returns,
14928 but twisted together in a fashion that parallels the syntax of C.
14929
14930 FLAGS is a bitwise or of SF_PRE_PARSED (indicating that the
14931 DECLARATOR is really the DECL for the function we are about to
14932 process and that DECLSPECS should be ignored), SF_INCLASS_INLINE
14933 indicating that the function is an inline defined in-class.
14934
14935 This function creates a binding context for the function body
14936 as well as setting up the FUNCTION_DECL in current_function_decl.
14937
14938 For C++, we must first check whether that datum makes any sense.
14939 For example, "class A local_a(1,2);" means that variable local_a
14940 is an aggregate of type A, which should have a constructor
14941 applied to it with the argument list [1, 2].
14942
14943 On entry, DECL_INITIAL (decl1) should be NULL_TREE or error_mark_node,
14944 or may be a BLOCK if the function has been defined previously
14945 in this translation unit. On exit, DECL_INITIAL (decl1) will be
14946 error_mark_node if the function has never been defined, or
14947 a BLOCK if the function has been defined somewhere. */
14948
14949 bool
start_preparsed_function(tree decl1,tree attrs,int flags)14950 start_preparsed_function (tree decl1, tree attrs, int flags)
14951 {
14952 tree ctype = NULL_TREE;
14953 tree fntype;
14954 tree restype;
14955 int doing_friend = 0;
14956 cp_binding_level *bl;
14957 tree current_function_parms;
14958 struct c_fileinfo *finfo
14959 = get_fileinfo (LOCATION_FILE (DECL_SOURCE_LOCATION (decl1)));
14960 bool honor_interface;
14961
14962 /* Sanity check. */
14963 gcc_assert (VOID_TYPE_P (TREE_VALUE (void_list_node)));
14964 gcc_assert (TREE_CHAIN (void_list_node) == NULL_TREE);
14965
14966 fntype = TREE_TYPE (decl1);
14967 if (TREE_CODE (fntype) == METHOD_TYPE)
14968 ctype = TYPE_METHOD_BASETYPE (fntype);
14969
14970 /* ISO C++ 11.4/5. A friend function defined in a class is in
14971 the (lexical) scope of the class in which it is defined. */
14972 if (!ctype && DECL_FRIEND_P (decl1))
14973 {
14974 ctype = DECL_FRIEND_CONTEXT (decl1);
14975
14976 /* CTYPE could be null here if we're dealing with a template;
14977 for example, `inline friend float foo()' inside a template
14978 will have no CTYPE set. */
14979 if (ctype && TREE_CODE (ctype) != RECORD_TYPE)
14980 ctype = NULL_TREE;
14981 else
14982 doing_friend = 1;
14983 }
14984
14985 if (DECL_DECLARED_INLINE_P (decl1)
14986 && lookup_attribute ("noinline", attrs))
14987 warning_at (DECL_SOURCE_LOCATION (decl1), 0,
14988 "inline function %qD given attribute noinline", decl1);
14989
14990 /* Handle gnu_inline attribute. */
14991 if (GNU_INLINE_P (decl1))
14992 {
14993 DECL_EXTERNAL (decl1) = 1;
14994 DECL_NOT_REALLY_EXTERN (decl1) = 0;
14995 DECL_INTERFACE_KNOWN (decl1) = 1;
14996 DECL_DISREGARD_INLINE_LIMITS (decl1) = 1;
14997 }
14998
14999 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl1))
15000 /* This is a constructor, we must ensure that any default args
15001 introduced by this definition are propagated to the clones
15002 now. The clones are used directly in overload resolution. */
15003 adjust_clone_args (decl1);
15004
15005 /* Sometimes we don't notice that a function is a static member, and
15006 build a METHOD_TYPE for it. Fix that up now. */
15007 gcc_assert (!(ctype != NULL_TREE && DECL_STATIC_FUNCTION_P (decl1)
15008 && TREE_CODE (TREE_TYPE (decl1)) == METHOD_TYPE));
15009
15010 /* Set up current_class_type, and enter the scope of the class, if
15011 appropriate. */
15012 if (ctype)
15013 push_nested_class (ctype);
15014 else if (DECL_STATIC_FUNCTION_P (decl1))
15015 push_nested_class (DECL_CONTEXT (decl1));
15016
15017 /* Now that we have entered the scope of the class, we must restore
15018 the bindings for any template parameters surrounding DECL1, if it
15019 is an inline member template. (Order is important; consider the
15020 case where a template parameter has the same name as a field of
15021 the class.) It is not until after this point that
15022 PROCESSING_TEMPLATE_DECL is guaranteed to be set up correctly. */
15023 if (flags & SF_INCLASS_INLINE)
15024 maybe_begin_member_template_processing (decl1);
15025
15026 /* Effective C++ rule 15. */
15027 if (warn_ecpp
15028 && DECL_ASSIGNMENT_OPERATOR_P (decl1)
15029 && DECL_OVERLOADED_OPERATOR_IS (decl1, NOP_EXPR)
15030 && VOID_TYPE_P (TREE_TYPE (fntype)))
15031 warning (OPT_Weffc__,
15032 "%<operator=%> should return a reference to %<*this%>");
15033
15034 /* Make the init_value nonzero so pushdecl knows this is not tentative.
15035 error_mark_node is replaced below (in poplevel) with the BLOCK. */
15036 if (!DECL_INITIAL (decl1))
15037 DECL_INITIAL (decl1) = error_mark_node;
15038
15039 /* This function exists in static storage.
15040 (This does not mean `static' in the C sense!) */
15041 TREE_STATIC (decl1) = 1;
15042
15043 /* We must call push_template_decl after current_class_type is set
15044 up. (If we are processing inline definitions after exiting a
15045 class scope, current_class_type will be NULL_TREE until set above
15046 by push_nested_class.) */
15047 if (processing_template_decl)
15048 {
15049 tree newdecl1 = push_template_decl (decl1);
15050 if (newdecl1 == error_mark_node)
15051 {
15052 if (ctype || DECL_STATIC_FUNCTION_P (decl1))
15053 pop_nested_class ();
15054 return false;
15055 }
15056 decl1 = newdecl1;
15057 }
15058
15059 /* Make sure the parameter and return types are reasonable. When
15060 you declare a function, these types can be incomplete, but they
15061 must be complete when you define the function. */
15062 check_function_type (decl1, DECL_ARGUMENTS (decl1));
15063
15064 /* Build the return declaration for the function. */
15065 restype = TREE_TYPE (fntype);
15066
15067 if (DECL_RESULT (decl1) == NULL_TREE)
15068 {
15069 tree resdecl;
15070
15071 resdecl = build_decl (input_location, RESULT_DECL, 0, restype);
15072 DECL_ARTIFICIAL (resdecl) = 1;
15073 DECL_IGNORED_P (resdecl) = 1;
15074 DECL_RESULT (decl1) = resdecl;
15075
15076 cp_apply_type_quals_to_decl (cp_type_quals (restype), resdecl);
15077 }
15078
15079 /* Record the decl so that the function name is defined.
15080 If we already have a decl for this name, and it is a FUNCTION_DECL,
15081 use the old decl. */
15082 if (!processing_template_decl && !(flags & SF_PRE_PARSED))
15083 {
15084 /* A specialization is not used to guide overload resolution. */
15085 if (!DECL_FUNCTION_MEMBER_P (decl1)
15086 && !(DECL_USE_TEMPLATE (decl1) &&
15087 PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl1))))
15088 {
15089 tree olddecl = pushdecl (decl1);
15090
15091 if (olddecl == error_mark_node)
15092 /* If something went wrong when registering the declaration,
15093 use DECL1; we have to have a FUNCTION_DECL to use when
15094 parsing the body of the function. */
15095 ;
15096 else
15097 {
15098 /* Otherwise, OLDDECL is either a previous declaration
15099 of the same function or DECL1 itself. */
15100
15101 if (warn_missing_declarations
15102 && olddecl == decl1
15103 && !DECL_MAIN_P (decl1)
15104 && TREE_PUBLIC (decl1)
15105 && !DECL_DECLARED_INLINE_P (decl1))
15106 {
15107 tree context;
15108
15109 /* Check whether DECL1 is in an anonymous
15110 namespace. */
15111 for (context = DECL_CONTEXT (decl1);
15112 context;
15113 context = DECL_CONTEXT (context))
15114 {
15115 if (TREE_CODE (context) == NAMESPACE_DECL
15116 && DECL_NAME (context) == NULL_TREE)
15117 break;
15118 }
15119
15120 if (context == NULL)
15121 warning_at (DECL_SOURCE_LOCATION (decl1),
15122 OPT_Wmissing_declarations,
15123 "no previous declaration for %qD", decl1);
15124 }
15125
15126 decl1 = olddecl;
15127 }
15128 }
15129 else
15130 {
15131 /* We need to set the DECL_CONTEXT. */
15132 if (!DECL_CONTEXT (decl1) && DECL_TEMPLATE_INFO (decl1))
15133 DECL_CONTEXT (decl1) = DECL_CONTEXT (DECL_TI_TEMPLATE (decl1));
15134 }
15135 fntype = TREE_TYPE (decl1);
15136 restype = TREE_TYPE (fntype);
15137
15138 /* If #pragma weak applies, mark the decl appropriately now.
15139 The pragma only applies to global functions. Because
15140 determining whether or not the #pragma applies involves
15141 computing the mangled name for the declaration, we cannot
15142 apply the pragma until after we have merged this declaration
15143 with any previous declarations; if the original declaration
15144 has a linkage specification, that specification applies to
15145 the definition as well, and may affect the mangled name. */
15146 if (DECL_FILE_SCOPE_P (decl1))
15147 maybe_apply_pragma_weak (decl1);
15148 }
15149
15150 /* We are now in the scope of the function being defined. */
15151 current_function_decl = decl1;
15152
15153 /* Save the parm names or decls from this function's declarator
15154 where store_parm_decls will find them. */
15155 current_function_parms = DECL_ARGUMENTS (decl1);
15156
15157 /* Let the user know we're compiling this function. */
15158 announce_function (decl1);
15159
15160 gcc_assert (DECL_INITIAL (decl1));
15161
15162 /* This function may already have been parsed, in which case just
15163 return; our caller will skip over the body without parsing. */
15164 if (DECL_INITIAL (decl1) != error_mark_node)
15165 return true;
15166
15167 /* Initialize RTL machinery. We cannot do this until
15168 CURRENT_FUNCTION_DECL and DECL_RESULT are set up. We do this
15169 even when processing a template; this is how we get
15170 CFUN set up, and our per-function variables initialized.
15171 FIXME factor out the non-RTL stuff. */
15172 bl = current_binding_level;
15173 allocate_struct_function (decl1, processing_template_decl);
15174
15175 /* Initialize the language data structures. Whenever we start
15176 a new function, we destroy temporaries in the usual way. */
15177 cfun->language = ggc_cleared_alloc<language_function> ();
15178 current_stmt_tree ()->stmts_are_full_exprs_p = 1;
15179 current_binding_level = bl;
15180
15181 if (!processing_template_decl && type_uses_auto (restype))
15182 {
15183 FNDECL_USED_AUTO (decl1) = true;
15184 current_function_auto_return_pattern = restype;
15185 }
15186
15187 /* Start the statement-tree, start the tree now. */
15188 DECL_SAVED_TREE (decl1) = push_stmt_list ();
15189
15190 /* If we are (erroneously) defining a function that we have already
15191 defined before, wipe out what we knew before. */
15192 if (!DECL_PENDING_INLINE_P (decl1))
15193 DECL_SAVED_FUNCTION_DATA (decl1) = NULL;
15194
15195 if (ctype && !doing_friend && !DECL_STATIC_FUNCTION_P (decl1))
15196 {
15197 /* We know that this was set up by `grokclassfn'. We do not
15198 wait until `store_parm_decls', since evil parse errors may
15199 never get us to that point. Here we keep the consistency
15200 between `current_class_type' and `current_class_ptr'. */
15201 tree t = DECL_ARGUMENTS (decl1);
15202
15203 gcc_assert (t != NULL_TREE && TREE_CODE (t) == PARM_DECL);
15204 gcc_assert (TYPE_PTR_P (TREE_TYPE (t)));
15205
15206 cp_function_chain->x_current_class_ref
15207 = cp_build_fold_indirect_ref (t);
15208 /* Set this second to avoid shortcut in cp_build_indirect_ref. */
15209 cp_function_chain->x_current_class_ptr = t;
15210
15211 /* Constructors and destructors need to know whether they're "in
15212 charge" of initializing virtual base classes. */
15213 t = DECL_CHAIN (t);
15214 if (DECL_HAS_IN_CHARGE_PARM_P (decl1))
15215 {
15216 current_in_charge_parm = t;
15217 t = DECL_CHAIN (t);
15218 }
15219 if (DECL_HAS_VTT_PARM_P (decl1))
15220 {
15221 gcc_assert (DECL_NAME (t) == vtt_parm_identifier);
15222 current_vtt_parm = t;
15223 }
15224 }
15225
15226 honor_interface = (!DECL_TEMPLATE_INSTANTIATION (decl1)
15227 /* Implicitly-defined methods (like the
15228 destructor for a class in which no destructor
15229 is explicitly declared) must not be defined
15230 until their definition is needed. So, we
15231 ignore interface specifications for
15232 compiler-generated functions. */
15233 && !DECL_ARTIFICIAL (decl1));
15234
15235 if (processing_template_decl)
15236 /* Don't mess with interface flags. */;
15237 else if (DECL_INTERFACE_KNOWN (decl1))
15238 {
15239 tree ctx = decl_function_context (decl1);
15240
15241 if (DECL_NOT_REALLY_EXTERN (decl1))
15242 DECL_EXTERNAL (decl1) = 0;
15243
15244 if (ctx != NULL_TREE && vague_linkage_p (ctx))
15245 /* This is a function in a local class in an extern inline
15246 or template function. */
15247 comdat_linkage (decl1);
15248 }
15249 /* If this function belongs to an interface, it is public.
15250 If it belongs to someone else's interface, it is also external.
15251 This only affects inlines and template instantiations. */
15252 else if (!finfo->interface_unknown && honor_interface)
15253 {
15254 if (DECL_DECLARED_INLINE_P (decl1)
15255 || DECL_TEMPLATE_INSTANTIATION (decl1))
15256 {
15257 DECL_EXTERNAL (decl1)
15258 = (finfo->interface_only
15259 || (DECL_DECLARED_INLINE_P (decl1)
15260 && ! flag_implement_inlines
15261 && !DECL_VINDEX (decl1)));
15262
15263 /* For WIN32 we also want to put these in linkonce sections. */
15264 maybe_make_one_only (decl1);
15265 }
15266 else
15267 DECL_EXTERNAL (decl1) = 0;
15268 DECL_INTERFACE_KNOWN (decl1) = 1;
15269 /* If this function is in an interface implemented in this file,
15270 make sure that the back end knows to emit this function
15271 here. */
15272 if (!DECL_EXTERNAL (decl1))
15273 mark_needed (decl1);
15274 }
15275 else if (finfo->interface_unknown && finfo->interface_only
15276 && honor_interface)
15277 {
15278 /* If MULTIPLE_SYMBOL_SPACES is defined and we saw a #pragma
15279 interface, we will have both finfo->interface_unknown and
15280 finfo->interface_only set. In that case, we don't want to
15281 use the normal heuristics because someone will supply a
15282 #pragma implementation elsewhere, and deducing it here would
15283 produce a conflict. */
15284 comdat_linkage (decl1);
15285 DECL_EXTERNAL (decl1) = 0;
15286 DECL_INTERFACE_KNOWN (decl1) = 1;
15287 DECL_DEFER_OUTPUT (decl1) = 1;
15288 }
15289 else
15290 {
15291 /* This is a definition, not a reference.
15292 So clear DECL_EXTERNAL, unless this is a GNU extern inline. */
15293 if (!GNU_INLINE_P (decl1))
15294 DECL_EXTERNAL (decl1) = 0;
15295
15296 if ((DECL_DECLARED_INLINE_P (decl1)
15297 || DECL_TEMPLATE_INSTANTIATION (decl1))
15298 && ! DECL_INTERFACE_KNOWN (decl1))
15299 DECL_DEFER_OUTPUT (decl1) = 1;
15300 else
15301 DECL_INTERFACE_KNOWN (decl1) = 1;
15302 }
15303
15304 /* Determine the ELF visibility attribute for the function. We must not
15305 do this before calling "pushdecl", as we must allow "duplicate_decls"
15306 to merge any attributes appropriately. We also need to wait until
15307 linkage is set. */
15308 if (!DECL_CLONED_FUNCTION_P (decl1))
15309 determine_visibility (decl1);
15310
15311 if (!processing_template_decl)
15312 maybe_instantiate_noexcept (decl1);
15313
15314 begin_scope (sk_function_parms, decl1);
15315
15316 ++function_depth;
15317
15318 if (DECL_DESTRUCTOR_P (decl1)
15319 || (DECL_CONSTRUCTOR_P (decl1)
15320 && targetm.cxx.cdtor_returns_this ()))
15321 {
15322 cdtor_label = create_artificial_label (input_location);
15323 LABEL_DECL_CDTOR (cdtor_label) = true;
15324 }
15325
15326 start_fname_decls ();
15327
15328 store_parm_decls (current_function_parms);
15329
15330 if (!processing_template_decl
15331 && (flag_lifetime_dse > 1)
15332 && DECL_CONSTRUCTOR_P (decl1)
15333 && !DECL_CLONED_FUNCTION_P (decl1)
15334 /* Clobbering an empty base is harmful if it overlays real data. */
15335 && !is_empty_class (current_class_type)
15336 /* We can't clobber safely for an implicitly-defined default constructor
15337 because part of the initialization might happen before we enter the
15338 constructor, via AGGR_INIT_ZERO_FIRST (c++/68006). */
15339 && !implicit_default_ctor_p (decl1))
15340 finish_expr_stmt (build_clobber_this ());
15341
15342 if (!processing_template_decl
15343 && DECL_CONSTRUCTOR_P (decl1)
15344 && sanitize_flags_p (SANITIZE_VPTR)
15345 && !DECL_CLONED_FUNCTION_P (decl1)
15346 && !implicit_default_ctor_p (decl1))
15347 cp_ubsan_maybe_initialize_vtbl_ptrs (current_class_ptr);
15348
15349 start_lambda_scope (decl1);
15350
15351 return true;
15352 }
15353
15354
15355 /* Like start_preparsed_function, except that instead of a
15356 FUNCTION_DECL, this function takes DECLSPECS and DECLARATOR.
15357
15358 Returns true on success. If the DECLARATOR is not suitable
15359 for a function, we return false, which tells the parser to
15360 skip the entire function. */
15361
15362 bool
start_function(cp_decl_specifier_seq * declspecs,const cp_declarator * declarator,tree attrs)15363 start_function (cp_decl_specifier_seq *declspecs,
15364 const cp_declarator *declarator,
15365 tree attrs)
15366 {
15367 tree decl1;
15368
15369 decl1 = grokdeclarator (declarator, declspecs, FUNCDEF, 1, &attrs);
15370 invoke_plugin_callbacks (PLUGIN_START_PARSE_FUNCTION, decl1);
15371 if (decl1 == error_mark_node)
15372 return false;
15373 /* If the declarator is not suitable for a function definition,
15374 cause a syntax error. */
15375 if (decl1 == NULL_TREE || TREE_CODE (decl1) != FUNCTION_DECL)
15376 {
15377 error ("invalid function declaration");
15378 return false;
15379 }
15380
15381 if (DECL_MAIN_P (decl1))
15382 /* main must return int. grokfndecl should have corrected it
15383 (and issued a diagnostic) if the user got it wrong. */
15384 gcc_assert (same_type_p (TREE_TYPE (TREE_TYPE (decl1)),
15385 integer_type_node));
15386
15387 return start_preparsed_function (decl1, attrs, /*flags=*/SF_DEFAULT);
15388 }
15389
15390 /* Returns true iff an EH_SPEC_BLOCK should be created in the body of
15391 FN. */
15392
15393 static bool
use_eh_spec_block(tree fn)15394 use_eh_spec_block (tree fn)
15395 {
15396 return (flag_exceptions && flag_enforce_eh_specs
15397 && !processing_template_decl
15398 && !type_throw_all_p (TREE_TYPE (fn))
15399 /* We insert the EH_SPEC_BLOCK only in the original
15400 function; then, it is copied automatically to the
15401 clones. */
15402 && !DECL_CLONED_FUNCTION_P (fn)
15403 /* Implicitly-generated constructors and destructors have
15404 exception specifications. However, those specifications
15405 are the union of the possible exceptions specified by the
15406 constructors/destructors for bases and members, so no
15407 unallowed exception will ever reach this function. By
15408 not creating the EH_SPEC_BLOCK we save a little memory,
15409 and we avoid spurious warnings about unreachable
15410 code. */
15411 && !DECL_DEFAULTED_FN (fn));
15412 }
15413
15414 /* Store the parameter declarations into the current function declaration.
15415 This is called after parsing the parameter declarations, before
15416 digesting the body of the function.
15417
15418 Also install to binding contour return value identifier, if any. */
15419
15420 static void
store_parm_decls(tree current_function_parms)15421 store_parm_decls (tree current_function_parms)
15422 {
15423 tree fndecl = current_function_decl;
15424 tree parm;
15425
15426 /* This is a chain of any other decls that came in among the parm
15427 declarations. If a parm is declared with enum {foo, bar} x;
15428 then CONST_DECLs for foo and bar are put here. */
15429 tree nonparms = NULL_TREE;
15430
15431 if (current_function_parms)
15432 {
15433 /* This case is when the function was defined with an ANSI prototype.
15434 The parms already have decls, so we need not do anything here
15435 except record them as in effect
15436 and complain if any redundant old-style parm decls were written. */
15437
15438 tree specparms = current_function_parms;
15439 tree next;
15440
15441 /* Must clear this because it might contain TYPE_DECLs declared
15442 at class level. */
15443 current_binding_level->names = NULL;
15444
15445 /* If we're doing semantic analysis, then we'll call pushdecl
15446 for each of these. We must do them in reverse order so that
15447 they end in the correct forward order. */
15448 specparms = nreverse (specparms);
15449
15450 for (parm = specparms; parm; parm = next)
15451 {
15452 next = DECL_CHAIN (parm);
15453 if (TREE_CODE (parm) == PARM_DECL)
15454 pushdecl (parm);
15455 else
15456 {
15457 /* If we find an enum constant or a type tag,
15458 put it aside for the moment. */
15459 TREE_CHAIN (parm) = NULL_TREE;
15460 nonparms = chainon (nonparms, parm);
15461 }
15462 }
15463
15464 /* Get the decls in their original chain order and record in the
15465 function. This is all and only the PARM_DECLs that were
15466 pushed into scope by the loop above. */
15467 DECL_ARGUMENTS (fndecl) = get_local_decls ();
15468 }
15469 else
15470 DECL_ARGUMENTS (fndecl) = NULL_TREE;
15471
15472 /* Now store the final chain of decls for the arguments
15473 as the decl-chain of the current lexical scope.
15474 Put the enumerators in as well, at the front so that
15475 DECL_ARGUMENTS is not modified. */
15476 current_binding_level->names = chainon (nonparms, DECL_ARGUMENTS (fndecl));
15477
15478 if (use_eh_spec_block (current_function_decl))
15479 current_eh_spec_block = begin_eh_spec_block ();
15480 }
15481
15482
15483 /* We have finished doing semantic analysis on DECL, but have not yet
15484 generated RTL for its body. Save away our current state, so that
15485 when we want to generate RTL later we know what to do. */
15486
15487 static void
save_function_data(tree decl)15488 save_function_data (tree decl)
15489 {
15490 struct language_function *f;
15491
15492 /* Save the language-specific per-function data so that we can
15493 get it back when we really expand this function. */
15494 gcc_assert (!DECL_PENDING_INLINE_P (decl));
15495
15496 /* Make a copy. */
15497 f = ggc_alloc<language_function> ();
15498 memcpy (f, cp_function_chain, sizeof (struct language_function));
15499 DECL_SAVED_FUNCTION_DATA (decl) = f;
15500
15501 /* Clear out the bits we don't need. */
15502 f->base.x_stmt_tree.x_cur_stmt_list = NULL;
15503 f->bindings = NULL;
15504 f->x_local_names = NULL;
15505 f->base.local_typedefs = NULL;
15506 }
15507
15508
15509 /* Set the return value of the constructor (if present). */
15510
15511 static void
finish_constructor_body(void)15512 finish_constructor_body (void)
15513 {
15514 tree val;
15515 tree exprstmt;
15516
15517 if (targetm.cxx.cdtor_returns_this ())
15518 {
15519 /* Any return from a constructor will end up here. */
15520 add_stmt (build_stmt (input_location, LABEL_EXPR, cdtor_label));
15521
15522 val = DECL_ARGUMENTS (current_function_decl);
15523 val = build2 (MODIFY_EXPR, TREE_TYPE (val),
15524 DECL_RESULT (current_function_decl), val);
15525 /* Return the address of the object. */
15526 exprstmt = build_stmt (input_location, RETURN_EXPR, val);
15527 add_stmt (exprstmt);
15528 }
15529 }
15530
15531 /* Do all the processing for the beginning of a destructor; set up the
15532 vtable pointers and cleanups for bases and members. */
15533
15534 static void
begin_destructor_body(void)15535 begin_destructor_body (void)
15536 {
15537 tree compound_stmt;
15538
15539 /* If the CURRENT_CLASS_TYPE is incomplete, we will have already
15540 issued an error message. We still want to try to process the
15541 body of the function, but initialize_vtbl_ptrs will crash if
15542 TYPE_BINFO is NULL. */
15543 if (COMPLETE_TYPE_P (current_class_type))
15544 {
15545 compound_stmt = begin_compound_stmt (0);
15546 /* Make all virtual function table pointers in non-virtual base
15547 classes point to CURRENT_CLASS_TYPE's virtual function
15548 tables. */
15549 initialize_vtbl_ptrs (current_class_ptr);
15550 finish_compound_stmt (compound_stmt);
15551
15552 if (flag_lifetime_dse
15553 /* Clobbering an empty base is harmful if it overlays real data. */
15554 && !is_empty_class (current_class_type))
15555 {
15556 if (sanitize_flags_p (SANITIZE_VPTR)
15557 && (flag_sanitize_recover & SANITIZE_VPTR) == 0
15558 && TYPE_CONTAINS_VPTR_P (current_class_type))
15559 {
15560 tree binfo = TYPE_BINFO (current_class_type);
15561 tree ref
15562 = cp_build_fold_indirect_ref (current_class_ptr);
15563
15564 tree vtbl_ptr = build_vfield_ref (ref, TREE_TYPE (binfo));
15565 tree vtbl = build_zero_cst (TREE_TYPE (vtbl_ptr));
15566 tree stmt = cp_build_modify_expr (input_location, vtbl_ptr,
15567 NOP_EXPR, vtbl,
15568 tf_warning_or_error);
15569 /* If the vptr is shared with some virtual nearly empty base,
15570 don't clear it if not in charge, the dtor of the virtual
15571 nearly empty base will do that later. */
15572 if (CLASSTYPE_VBASECLASSES (current_class_type)
15573 && CLASSTYPE_PRIMARY_BINFO (current_class_type)
15574 && BINFO_VIRTUAL_P
15575 (CLASSTYPE_PRIMARY_BINFO (current_class_type)))
15576 {
15577 stmt = convert_to_void (stmt, ICV_STATEMENT,
15578 tf_warning_or_error);
15579 stmt = build_if_in_charge (stmt);
15580 }
15581 finish_decl_cleanup (NULL_TREE, stmt);
15582 }
15583 else
15584 finish_decl_cleanup (NULL_TREE, build_clobber_this ());
15585 }
15586
15587 /* And insert cleanups for our bases and members so that they
15588 will be properly destroyed if we throw. */
15589 push_base_cleanups ();
15590 }
15591 }
15592
15593 /* At the end of every destructor we generate code to delete the object if
15594 necessary. Do that now. */
15595
15596 static void
finish_destructor_body(void)15597 finish_destructor_body (void)
15598 {
15599 tree exprstmt;
15600
15601 /* Any return from a destructor will end up here; that way all base
15602 and member cleanups will be run when the function returns. */
15603 add_stmt (build_stmt (input_location, LABEL_EXPR, cdtor_label));
15604
15605 if (targetm.cxx.cdtor_returns_this ())
15606 {
15607 tree val;
15608
15609 val = DECL_ARGUMENTS (current_function_decl);
15610 val = build2 (MODIFY_EXPR, TREE_TYPE (val),
15611 DECL_RESULT (current_function_decl), val);
15612 /* Return the address of the object. */
15613 exprstmt = build_stmt (input_location, RETURN_EXPR, val);
15614 add_stmt (exprstmt);
15615 }
15616 }
15617
15618 /* Do the necessary processing for the beginning of a function body, which
15619 in this case includes member-initializers, but not the catch clauses of
15620 a function-try-block. Currently, this means opening a binding level
15621 for the member-initializers (in a ctor), member cleanups (in a dtor),
15622 and capture proxies (in a lambda operator()). */
15623
15624 tree
begin_function_body(void)15625 begin_function_body (void)
15626 {
15627 tree stmt;
15628
15629 if (! FUNCTION_NEEDS_BODY_BLOCK (current_function_decl))
15630 return NULL_TREE;
15631
15632 if (processing_template_decl)
15633 /* Do nothing now. */;
15634 else
15635 /* Always keep the BLOCK node associated with the outermost pair of
15636 curly braces of a function. These are needed for correct
15637 operation of dwarfout.c. */
15638 keep_next_level (true);
15639
15640 stmt = begin_compound_stmt (BCS_FN_BODY);
15641
15642 if (processing_template_decl)
15643 /* Do nothing now. */;
15644 else if (DECL_DESTRUCTOR_P (current_function_decl))
15645 begin_destructor_body ();
15646
15647 return stmt;
15648 }
15649
15650 /* Do the processing for the end of a function body. Currently, this means
15651 closing out the cleanups for fully-constructed bases and members, and in
15652 the case of the destructor, deleting the object if desired. Again, this
15653 is only meaningful for [cd]tors, since they are the only functions where
15654 there is a significant distinction between the main body and any
15655 function catch clauses. Handling, say, main() return semantics here
15656 would be wrong, as flowing off the end of a function catch clause for
15657 main() would also need to return 0. */
15658
15659 void
finish_function_body(tree compstmt)15660 finish_function_body (tree compstmt)
15661 {
15662 if (compstmt == NULL_TREE)
15663 return;
15664
15665 /* Close the block. */
15666 finish_compound_stmt (compstmt);
15667
15668 if (processing_template_decl)
15669 /* Do nothing now. */;
15670 else if (DECL_CONSTRUCTOR_P (current_function_decl))
15671 finish_constructor_body ();
15672 else if (DECL_DESTRUCTOR_P (current_function_decl))
15673 finish_destructor_body ();
15674 }
15675
15676 /* Given a function, returns the BLOCK corresponding to the outermost level
15677 of curly braces, skipping the artificial block created for constructor
15678 initializers. */
15679
15680 tree
outer_curly_brace_block(tree fndecl)15681 outer_curly_brace_block (tree fndecl)
15682 {
15683 tree block = DECL_INITIAL (fndecl);
15684 if (BLOCK_OUTER_CURLY_BRACE_P (block))
15685 return block;
15686 block = BLOCK_SUBBLOCKS (block);
15687 if (BLOCK_OUTER_CURLY_BRACE_P (block))
15688 return block;
15689 block = BLOCK_SUBBLOCKS (block);
15690 gcc_assert (BLOCK_OUTER_CURLY_BRACE_P (block));
15691 return block;
15692 }
15693
15694 /* If FNDECL is a class's key method, add the class to the list of
15695 keyed classes that should be emitted. */
15696
15697 static void
record_key_method_defined(tree fndecl)15698 record_key_method_defined (tree fndecl)
15699 {
15700 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fndecl)
15701 && DECL_VIRTUAL_P (fndecl)
15702 && !processing_template_decl)
15703 {
15704 tree fnclass = DECL_CONTEXT (fndecl);
15705 if (fndecl == CLASSTYPE_KEY_METHOD (fnclass))
15706 vec_safe_push (keyed_classes, fnclass);
15707 }
15708 }
15709
15710 /* Subroutine of finish_function.
15711 Save the body of constexpr functions for possible
15712 future compile time evaluation. */
15713
15714 static void
maybe_save_function_definition(tree fun)15715 maybe_save_function_definition (tree fun)
15716 {
15717 if (!processing_template_decl
15718 && DECL_DECLARED_CONSTEXPR_P (fun)
15719 && !cp_function_chain->invalid_constexpr
15720 && !DECL_CLONED_FUNCTION_P (fun))
15721 register_constexpr_fundef (fun, DECL_SAVED_TREE (fun));
15722 }
15723
15724 /* Finish up a function declaration and compile that function
15725 all the way to assembler language output. The free the storage
15726 for the function definition. INLINE_P is TRUE if we just
15727 finished processing the body of an in-class inline function
15728 definition. (This processing will have taken place after the
15729 class definition is complete.) */
15730
15731 tree
finish_function(bool inline_p)15732 finish_function (bool inline_p)
15733 {
15734 tree fndecl = current_function_decl;
15735 tree fntype, ctype = NULL_TREE;
15736
15737 /* When we get some parse errors, we can end up without a
15738 current_function_decl, so cope. */
15739 if (fndecl == NULL_TREE)
15740 return error_mark_node;
15741
15742 finish_lambda_scope ();
15743
15744 if (c_dialect_objc ())
15745 objc_finish_function ();
15746
15747 record_key_method_defined (fndecl);
15748
15749 fntype = TREE_TYPE (fndecl);
15750
15751 /* TREE_READONLY (fndecl) = 1;
15752 This caused &foo to be of type ptr-to-const-function
15753 which then got a warning when stored in a ptr-to-function variable. */
15754
15755 gcc_assert (building_stmt_list_p ());
15756 /* The current function is being defined, so its DECL_INITIAL should
15757 be set, and unless there's a multiple definition, it should be
15758 error_mark_node. */
15759 gcc_assert (DECL_INITIAL (fndecl) == error_mark_node);
15760
15761 /* For a cloned function, we've already got all the code we need;
15762 there's no need to add any extra bits. */
15763 if (!DECL_CLONED_FUNCTION_P (fndecl))
15764 {
15765 /* Make it so that `main' always returns 0 by default. */
15766 if (DECL_MAIN_P (current_function_decl))
15767 finish_return_stmt (integer_zero_node);
15768
15769 if (use_eh_spec_block (current_function_decl))
15770 finish_eh_spec_block (TYPE_RAISES_EXCEPTIONS
15771 (TREE_TYPE (current_function_decl)),
15772 current_eh_spec_block);
15773 }
15774
15775 /* If we're saving up tree structure, tie off the function now. */
15776 DECL_SAVED_TREE (fndecl) = pop_stmt_list (DECL_SAVED_TREE (fndecl));
15777
15778 finish_fname_decls ();
15779
15780 /* If this function can't throw any exceptions, remember that. */
15781 if (!processing_template_decl
15782 && !cp_function_chain->can_throw
15783 && !flag_non_call_exceptions
15784 && !decl_replaceable_p (fndecl))
15785 TREE_NOTHROW (fndecl) = 1;
15786
15787 /* This must come after expand_function_end because cleanups might
15788 have declarations (from inline functions) that need to go into
15789 this function's blocks. */
15790
15791 /* If the current binding level isn't the outermost binding level
15792 for this function, either there is a bug, or we have experienced
15793 syntax errors and the statement tree is malformed. */
15794 if (current_binding_level->kind != sk_function_parms)
15795 {
15796 /* Make sure we have already experienced errors. */
15797 gcc_assert (errorcount);
15798
15799 /* Throw away the broken statement tree and extra binding
15800 levels. */
15801 DECL_SAVED_TREE (fndecl) = alloc_stmt_list ();
15802
15803 while (current_binding_level->kind != sk_function_parms)
15804 {
15805 if (current_binding_level->kind == sk_class)
15806 pop_nested_class ();
15807 else
15808 poplevel (0, 0, 0);
15809 }
15810 }
15811 poplevel (1, 0, 1);
15812
15813 /* Statements should always be full-expressions at the outermost set
15814 of curly braces for a function. */
15815 gcc_assert (stmts_are_full_exprs_p ());
15816
15817 /* If there are no return statements in a function with auto return type,
15818 the return type is void. But if the declared type is something like
15819 auto*, this is an error. */
15820 if (!processing_template_decl && FNDECL_USED_AUTO (fndecl)
15821 && TREE_TYPE (fntype) == current_function_auto_return_pattern)
15822 {
15823 if (is_auto (current_function_auto_return_pattern))
15824 {
15825 apply_deduced_return_type (fndecl, void_type_node);
15826 fntype = TREE_TYPE (fndecl);
15827 }
15828 else if (!current_function_returns_value
15829 && !current_function_returns_null)
15830 {
15831 error ("no return statements in function returning %qT",
15832 current_function_auto_return_pattern);
15833 inform (input_location, "only plain %<auto%> return type can be "
15834 "deduced to %<void%>");
15835 }
15836 }
15837
15838 // If this is a concept, check that the definition is reasonable.
15839 if (DECL_DECLARED_CONCEPT_P (fndecl))
15840 check_function_concept (fndecl);
15841
15842 /* Lambda closure members are implicitly constexpr if possible. */
15843 if (cxx_dialect >= cxx17
15844 && LAMBDA_TYPE_P (CP_DECL_CONTEXT (fndecl)))
15845 DECL_DECLARED_CONSTEXPR_P (fndecl)
15846 = ((processing_template_decl
15847 || is_valid_constexpr_fn (fndecl, /*complain*/false))
15848 && potential_constant_expression (DECL_SAVED_TREE (fndecl)));
15849
15850 /* Save constexpr function body before it gets munged by
15851 the NRV transformation. */
15852 maybe_save_function_definition (fndecl);
15853
15854 /* Invoke the pre-genericize plugin before we start munging things. */
15855 if (!processing_template_decl)
15856 invoke_plugin_callbacks (PLUGIN_PRE_GENERICIZE, fndecl);
15857
15858 /* Perform delayed folding before NRV transformation. */
15859 if (!processing_template_decl)
15860 cp_fold_function (fndecl);
15861
15862 /* Set up the named return value optimization, if we can. Candidate
15863 variables are selected in check_return_expr. */
15864 if (current_function_return_value)
15865 {
15866 tree r = current_function_return_value;
15867 tree outer;
15868
15869 if (r != error_mark_node
15870 /* This is only worth doing for fns that return in memory--and
15871 simpler, since we don't have to worry about promoted modes. */
15872 && aggregate_value_p (TREE_TYPE (TREE_TYPE (fndecl)), fndecl)
15873 /* Only allow this for variables declared in the outer scope of
15874 the function so we know that their lifetime always ends with a
15875 return; see g++.dg/opt/nrv6.C. We could be more flexible if
15876 we were to do this optimization in tree-ssa. */
15877 && (outer = outer_curly_brace_block (fndecl))
15878 && chain_member (r, BLOCK_VARS (outer)))
15879 finalize_nrv (&DECL_SAVED_TREE (fndecl), r, DECL_RESULT (fndecl));
15880
15881 current_function_return_value = NULL_TREE;
15882 }
15883
15884 /* Remember that we were in class scope. */
15885 if (current_class_name)
15886 ctype = current_class_type;
15887
15888 /* Must mark the RESULT_DECL as being in this function. */
15889 DECL_CONTEXT (DECL_RESULT (fndecl)) = fndecl;
15890
15891 /* Set the BLOCK_SUPERCONTEXT of the outermost function scope to point
15892 to the FUNCTION_DECL node itself. */
15893 BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
15894
15895 /* Save away current state, if appropriate. */
15896 if (!processing_template_decl)
15897 save_function_data (fndecl);
15898
15899 /* Complain if there's just no return statement. */
15900 if (warn_return_type
15901 && !VOID_TYPE_P (TREE_TYPE (fntype))
15902 && !dependent_type_p (TREE_TYPE (fntype))
15903 && !current_function_returns_value && !current_function_returns_null
15904 /* Don't complain if we abort or throw. */
15905 && !current_function_returns_abnormally
15906 /* Don't complain if there's an infinite loop. */
15907 && !current_function_infinite_loop
15908 /* Don't complain if we are declared noreturn. */
15909 && !TREE_THIS_VOLATILE (fndecl)
15910 && !DECL_NAME (DECL_RESULT (fndecl))
15911 && !TREE_NO_WARNING (fndecl)
15912 /* Structor return values (if any) are set by the compiler. */
15913 && !DECL_CONSTRUCTOR_P (fndecl)
15914 && !DECL_DESTRUCTOR_P (fndecl)
15915 && targetm.warn_func_return (fndecl))
15916 {
15917 warning (OPT_Wreturn_type,
15918 "no return statement in function returning non-void");
15919 TREE_NO_WARNING (fndecl) = 1;
15920 }
15921
15922 /* Store the end of the function, so that we get good line number
15923 info for the epilogue. */
15924 cfun->function_end_locus = input_location;
15925
15926 /* Complain about parameters that are only set, but never otherwise used. */
15927 if (warn_unused_but_set_parameter
15928 && !processing_template_decl
15929 && errorcount == unused_but_set_errorcount
15930 && !DECL_CLONED_FUNCTION_P (fndecl))
15931 {
15932 tree decl;
15933
15934 for (decl = DECL_ARGUMENTS (fndecl);
15935 decl;
15936 decl = DECL_CHAIN (decl))
15937 if (TREE_USED (decl)
15938 && TREE_CODE (decl) == PARM_DECL
15939 && !DECL_READ_P (decl)
15940 && DECL_NAME (decl)
15941 && !DECL_ARTIFICIAL (decl)
15942 && !TREE_NO_WARNING (decl)
15943 && !DECL_IN_SYSTEM_HEADER (decl)
15944 && TREE_TYPE (decl) != error_mark_node
15945 && TREE_CODE (TREE_TYPE (decl)) != REFERENCE_TYPE
15946 && (!CLASS_TYPE_P (TREE_TYPE (decl))
15947 || !TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (decl))))
15948 warning_at (DECL_SOURCE_LOCATION (decl),
15949 OPT_Wunused_but_set_parameter,
15950 "parameter %qD set but not used", decl);
15951 unused_but_set_errorcount = errorcount;
15952 }
15953
15954 /* Complain about locally defined typedefs that are not used in this
15955 function. */
15956 maybe_warn_unused_local_typedefs ();
15957
15958 /* Possibly warn about unused parameters. */
15959 if (warn_unused_parameter
15960 && !processing_template_decl
15961 && !DECL_CLONED_FUNCTION_P (fndecl))
15962 do_warn_unused_parameter (fndecl);
15963
15964 /* Genericize before inlining. */
15965 if (!processing_template_decl)
15966 {
15967 struct language_function *f = DECL_SAVED_FUNCTION_DATA (fndecl);
15968 cp_genericize (fndecl);
15969 /* Clear out the bits we don't need. */
15970 f->x_current_class_ptr = NULL;
15971 f->x_current_class_ref = NULL;
15972 f->x_eh_spec_block = NULL;
15973 f->x_in_charge_parm = NULL;
15974 f->x_vtt_parm = NULL;
15975 f->x_return_value = NULL;
15976 f->bindings = NULL;
15977 f->extern_decl_map = NULL;
15978 f->infinite_loops = NULL;
15979 }
15980 /* Clear out the bits we don't need. */
15981 local_names = NULL;
15982
15983 /* We're leaving the context of this function, so zap cfun. It's still in
15984 DECL_STRUCT_FUNCTION, and we'll restore it in tree_rest_of_compilation. */
15985 set_cfun (NULL);
15986 current_function_decl = NULL;
15987
15988 /* If this is an in-class inline definition, we may have to pop the
15989 bindings for the template parameters that we added in
15990 maybe_begin_member_template_processing when start_function was
15991 called. */
15992 if (inline_p)
15993 maybe_end_member_template_processing ();
15994
15995 /* Leave the scope of the class. */
15996 if (ctype)
15997 pop_nested_class ();
15998
15999 --function_depth;
16000
16001 /* Clean up. */
16002 current_function_decl = NULL_TREE;
16003
16004 invoke_plugin_callbacks (PLUGIN_FINISH_PARSE_FUNCTION, fndecl);
16005 return fndecl;
16006 }
16007
16008 /* Create the FUNCTION_DECL for a function definition.
16009 DECLSPECS and DECLARATOR are the parts of the declaration;
16010 they describe the return type and the name of the function,
16011 but twisted together in a fashion that parallels the syntax of C.
16012
16013 This function creates a binding context for the function body
16014 as well as setting up the FUNCTION_DECL in current_function_decl.
16015
16016 Returns a FUNCTION_DECL on success.
16017
16018 If the DECLARATOR is not suitable for a function (it defines a datum
16019 instead), we return 0, which tells yyparse to report a parse error.
16020
16021 May return void_type_node indicating that this method is actually
16022 a friend. See grokfield for more details.
16023
16024 Came here with a `.pushlevel' .
16025
16026 DO NOT MAKE ANY CHANGES TO THIS CODE WITHOUT MAKING CORRESPONDING
16027 CHANGES TO CODE IN `grokfield'. */
16028
16029 tree
grokmethod(cp_decl_specifier_seq * declspecs,const cp_declarator * declarator,tree attrlist)16030 grokmethod (cp_decl_specifier_seq *declspecs,
16031 const cp_declarator *declarator, tree attrlist)
16032 {
16033 tree fndecl = grokdeclarator (declarator, declspecs, MEMFUNCDEF, 0,
16034 &attrlist);
16035
16036 if (fndecl == error_mark_node)
16037 return error_mark_node;
16038
16039 if (fndecl == NULL || TREE_CODE (fndecl) != FUNCTION_DECL)
16040 {
16041 error ("invalid member function declaration");
16042 return error_mark_node;
16043 }
16044
16045 if (attrlist)
16046 cplus_decl_attributes (&fndecl, attrlist, 0);
16047
16048 /* Pass friends other than inline friend functions back. */
16049 if (fndecl == void_type_node)
16050 return fndecl;
16051
16052 if (DECL_IN_AGGR_P (fndecl))
16053 {
16054 if (DECL_CLASS_SCOPE_P (fndecl))
16055 error ("%qD is already defined in class %qT", fndecl,
16056 DECL_CONTEXT (fndecl));
16057 return error_mark_node;
16058 }
16059
16060 check_template_shadow (fndecl);
16061
16062 if (TREE_PUBLIC (fndecl))
16063 DECL_COMDAT (fndecl) = 1;
16064 DECL_DECLARED_INLINE_P (fndecl) = 1;
16065 DECL_NO_INLINE_WARNING_P (fndecl) = 1;
16066
16067 /* We process method specializations in finish_struct_1. */
16068 if (processing_template_decl && !DECL_TEMPLATE_SPECIALIZATION (fndecl))
16069 {
16070 fndecl = push_template_decl (fndecl);
16071 if (fndecl == error_mark_node)
16072 return fndecl;
16073 }
16074
16075 if (! DECL_FRIEND_P (fndecl))
16076 {
16077 if (DECL_CHAIN (fndecl))
16078 {
16079 fndecl = copy_node (fndecl);
16080 TREE_CHAIN (fndecl) = NULL_TREE;
16081 }
16082 }
16083
16084 cp_finish_decl (fndecl, NULL_TREE, false, NULL_TREE, 0);
16085
16086 DECL_IN_AGGR_P (fndecl) = 1;
16087 return fndecl;
16088 }
16089
16090
16091 /* VAR is a VAR_DECL. If its type is incomplete, remember VAR so that
16092 we can lay it out later, when and if its type becomes complete.
16093
16094 Also handle constexpr variables where the initializer involves
16095 an unlowered PTRMEM_CST because the class isn't complete yet. */
16096
16097 void
maybe_register_incomplete_var(tree var)16098 maybe_register_incomplete_var (tree var)
16099 {
16100 gcc_assert (VAR_P (var));
16101
16102 /* Keep track of variables with incomplete types. */
16103 if (!processing_template_decl && TREE_TYPE (var) != error_mark_node
16104 && DECL_EXTERNAL (var))
16105 {
16106 tree inner_type = TREE_TYPE (var);
16107
16108 while (TREE_CODE (inner_type) == ARRAY_TYPE)
16109 inner_type = TREE_TYPE (inner_type);
16110 inner_type = TYPE_MAIN_VARIANT (inner_type);
16111
16112 if ((!COMPLETE_TYPE_P (inner_type) && CLASS_TYPE_P (inner_type))
16113 /* RTTI TD entries are created while defining the type_info. */
16114 || (TYPE_LANG_SPECIFIC (inner_type)
16115 && TYPE_BEING_DEFINED (inner_type)))
16116 {
16117 incomplete_var iv = {var, inner_type};
16118 vec_safe_push (incomplete_vars, iv);
16119 }
16120 else if (!(DECL_LANG_SPECIFIC (var) && DECL_TEMPLATE_INFO (var))
16121 && decl_constant_var_p (var)
16122 && (TYPE_PTRMEM_P (inner_type) || CLASS_TYPE_P (inner_type)))
16123 {
16124 /* When the outermost open class is complete we can resolve any
16125 pointers-to-members. */
16126 tree context = outermost_open_class ();
16127 incomplete_var iv = {var, context};
16128 vec_safe_push (incomplete_vars, iv);
16129 }
16130 }
16131 }
16132
16133 /* Called when a class type (given by TYPE) is defined. If there are
16134 any existing VAR_DECLs whose type has been completed by this
16135 declaration, update them now. */
16136
16137 void
complete_vars(tree type)16138 complete_vars (tree type)
16139 {
16140 unsigned ix;
16141 incomplete_var *iv;
16142
16143 for (ix = 0; vec_safe_iterate (incomplete_vars, ix, &iv); )
16144 {
16145 if (same_type_p (type, iv->incomplete_type))
16146 {
16147 tree var = iv->decl;
16148 tree type = TREE_TYPE (var);
16149
16150 if (type != error_mark_node
16151 && (TYPE_MAIN_VARIANT (strip_array_types (type))
16152 == iv->incomplete_type))
16153 {
16154 /* Complete the type of the variable. The VAR_DECL itself
16155 will be laid out in expand_expr. */
16156 complete_type (type);
16157 cp_apply_type_quals_to_decl (cp_type_quals (type), var);
16158 }
16159
16160 /* Remove this entry from the list. */
16161 incomplete_vars->unordered_remove (ix);
16162 }
16163 else
16164 ix++;
16165 }
16166
16167 /* Check for pending declarations which may have abstract type. */
16168 complete_type_check_abstract (type);
16169 }
16170
16171 /* If DECL is of a type which needs a cleanup, build and return an
16172 expression to perform that cleanup here. Return NULL_TREE if no
16173 cleanup need be done. DECL can also be a _REF when called from
16174 split_nonconstant_init_1. */
16175
16176 tree
cxx_maybe_build_cleanup(tree decl,tsubst_flags_t complain)16177 cxx_maybe_build_cleanup (tree decl, tsubst_flags_t complain)
16178 {
16179 tree type;
16180 tree attr;
16181 tree cleanup;
16182
16183 /* Assume no cleanup is required. */
16184 cleanup = NULL_TREE;
16185
16186 if (error_operand_p (decl))
16187 return cleanup;
16188
16189 /* Handle "__attribute__((cleanup))". We run the cleanup function
16190 before the destructor since the destructor is what actually
16191 terminates the lifetime of the object. */
16192 if (DECL_P (decl))
16193 attr = lookup_attribute ("cleanup", DECL_ATTRIBUTES (decl));
16194 else
16195 attr = NULL_TREE;
16196 if (attr)
16197 {
16198 tree id;
16199 tree fn;
16200 tree arg;
16201
16202 /* Get the name specified by the user for the cleanup function. */
16203 id = TREE_VALUE (TREE_VALUE (attr));
16204 /* Look up the name to find the cleanup function to call. It is
16205 important to use lookup_name here because that is what is
16206 used in c-common.c:handle_cleanup_attribute when performing
16207 initial checks on the attribute. Note that those checks
16208 include ensuring that the function found is not an overloaded
16209 function, or an object with an overloaded call operator,
16210 etc.; we can rely on the fact that the function found is an
16211 ordinary FUNCTION_DECL. */
16212 fn = lookup_name (id);
16213 arg = build_address (decl);
16214 if (!mark_used (decl, complain) && !(complain & tf_error))
16215 return error_mark_node;
16216 cleanup = cp_build_function_call_nary (fn, complain, arg, NULL_TREE);
16217 if (cleanup == error_mark_node)
16218 return error_mark_node;
16219 }
16220 /* Handle ordinary C++ destructors. */
16221 type = TREE_TYPE (decl);
16222 if (type_build_dtor_call (type))
16223 {
16224 int flags = LOOKUP_NORMAL|LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR;
16225 tree addr;
16226 tree call;
16227
16228 if (TREE_CODE (type) == ARRAY_TYPE)
16229 addr = decl;
16230 else
16231 addr = build_address (decl);
16232
16233 call = build_delete (TREE_TYPE (addr), addr,
16234 sfk_complete_destructor, flags, 0, complain);
16235 if (call == error_mark_node)
16236 cleanup = error_mark_node;
16237 else if (TYPE_HAS_TRIVIAL_DESTRUCTOR (type))
16238 /* Discard the call. */;
16239 else if (cleanup)
16240 cleanup = cp_build_compound_expr (cleanup, call, complain);
16241 else
16242 cleanup = call;
16243 }
16244
16245 /* build_delete sets the location of the destructor call to the
16246 current location, even though the destructor is going to be
16247 called later, at the end of the current scope. This can lead to
16248 a "jumpy" behavior for users of debuggers when they step around
16249 the end of the block. So let's unset the location of the
16250 destructor call instead. */
16251 protected_set_expr_location (cleanup, UNKNOWN_LOCATION);
16252
16253 if (cleanup
16254 && DECL_P (decl)
16255 && !lookup_attribute ("warn_unused", TYPE_ATTRIBUTES (TREE_TYPE (decl)))
16256 /* Treat objects with destructors as used; the destructor may do
16257 something substantive. */
16258 && !mark_used (decl, complain) && !(complain & tf_error))
16259 return error_mark_node;
16260
16261 return cleanup;
16262 }
16263
16264
16265 /* Return the FUNCTION_TYPE that corresponds to MEMFNTYPE, which can be a
16266 FUNCTION_DECL, METHOD_TYPE, FUNCTION_TYPE, pointer or reference to
16267 METHOD_TYPE or FUNCTION_TYPE, or pointer to member function. */
16268
16269 tree
static_fn_type(tree memfntype)16270 static_fn_type (tree memfntype)
16271 {
16272 tree fntype;
16273 tree args;
16274
16275 if (TYPE_PTRMEMFUNC_P (memfntype))
16276 memfntype = TYPE_PTRMEMFUNC_FN_TYPE (memfntype);
16277 if (POINTER_TYPE_P (memfntype)
16278 || TREE_CODE (memfntype) == FUNCTION_DECL)
16279 memfntype = TREE_TYPE (memfntype);
16280 if (TREE_CODE (memfntype) == FUNCTION_TYPE)
16281 return memfntype;
16282 gcc_assert (TREE_CODE (memfntype) == METHOD_TYPE);
16283 args = TYPE_ARG_TYPES (memfntype);
16284 cp_ref_qualifier rqual = type_memfn_rqual (memfntype);
16285 fntype = build_function_type (TREE_TYPE (memfntype), TREE_CHAIN (args));
16286 fntype = apply_memfn_quals (fntype, type_memfn_quals (memfntype), rqual);
16287 fntype = (cp_build_type_attribute_variant
16288 (fntype, TYPE_ATTRIBUTES (memfntype)));
16289 fntype = (build_exception_variant
16290 (fntype, TYPE_RAISES_EXCEPTIONS (memfntype)));
16291 if (TYPE_HAS_LATE_RETURN_TYPE (memfntype))
16292 TYPE_HAS_LATE_RETURN_TYPE (fntype) = 1;
16293 return fntype;
16294 }
16295
16296 /* DECL was originally constructed as a non-static member function,
16297 but turned out to be static. Update it accordingly. */
16298
16299 void
revert_static_member_fn(tree decl)16300 revert_static_member_fn (tree decl)
16301 {
16302 tree stype = static_fn_type (decl);
16303 cp_cv_quals quals = type_memfn_quals (stype);
16304 cp_ref_qualifier rqual = type_memfn_rqual (stype);
16305
16306 if (quals != TYPE_UNQUALIFIED || rqual != REF_QUAL_NONE)
16307 stype = apply_memfn_quals (stype, TYPE_UNQUALIFIED, REF_QUAL_NONE);
16308
16309 TREE_TYPE (decl) = stype;
16310
16311 if (DECL_ARGUMENTS (decl))
16312 DECL_ARGUMENTS (decl) = DECL_CHAIN (DECL_ARGUMENTS (decl));
16313 DECL_STATIC_FUNCTION_P (decl) = 1;
16314 }
16315
16316 /* Return which tree structure is used by T, or TS_CP_GENERIC if T is
16317 one of the language-independent trees. */
16318
16319 enum cp_tree_node_structure_enum
cp_tree_node_structure(union lang_tree_node * t)16320 cp_tree_node_structure (union lang_tree_node * t)
16321 {
16322 switch (TREE_CODE (&t->generic))
16323 {
16324 case DEFAULT_ARG: return TS_CP_DEFAULT_ARG;
16325 case DEFERRED_NOEXCEPT: return TS_CP_DEFERRED_NOEXCEPT;
16326 case IDENTIFIER_NODE: return TS_CP_IDENTIFIER;
16327 case OVERLOAD: return TS_CP_OVERLOAD;
16328 case TEMPLATE_PARM_INDEX: return TS_CP_TPI;
16329 case PTRMEM_CST: return TS_CP_PTRMEM;
16330 case BASELINK: return TS_CP_BASELINK;
16331 case TEMPLATE_DECL: return TS_CP_TEMPLATE_DECL;
16332 case STATIC_ASSERT: return TS_CP_STATIC_ASSERT;
16333 case ARGUMENT_PACK_SELECT: return TS_CP_ARGUMENT_PACK_SELECT;
16334 case TRAIT_EXPR: return TS_CP_TRAIT_EXPR;
16335 case LAMBDA_EXPR: return TS_CP_LAMBDA_EXPR;
16336 case TEMPLATE_INFO: return TS_CP_TEMPLATE_INFO;
16337 case CONSTRAINT_INFO: return TS_CP_CONSTRAINT_INFO;
16338 case USERDEF_LITERAL: return TS_CP_USERDEF_LITERAL;
16339 default: return TS_CP_GENERIC;
16340 }
16341 }
16342
16343 /* Build the void_list_node (void_type_node having been created). */
16344 tree
build_void_list_node(void)16345 build_void_list_node (void)
16346 {
16347 tree t = build_tree_list (NULL_TREE, void_type_node);
16348 return t;
16349 }
16350
16351 bool
cp_missing_noreturn_ok_p(tree decl)16352 cp_missing_noreturn_ok_p (tree decl)
16353 {
16354 /* A missing noreturn is ok for the `main' function. */
16355 return DECL_MAIN_P (decl);
16356 }
16357
16358 /* Return the decl used to identify the COMDAT group into which DECL should
16359 be placed. */
16360
16361 tree
cxx_comdat_group(tree decl)16362 cxx_comdat_group (tree decl)
16363 {
16364 /* Virtual tables, construction virtual tables, and virtual table
16365 tables all go in a single COMDAT group, named after the primary
16366 virtual table. */
16367 if (VAR_P (decl) && DECL_VTABLE_OR_VTT_P (decl))
16368 decl = CLASSTYPE_VTABLES (DECL_CONTEXT (decl));
16369 /* For all other DECLs, the COMDAT group is the mangled name of the
16370 declaration itself. */
16371 else
16372 {
16373 while (DECL_THUNK_P (decl))
16374 {
16375 /* If TARGET_USE_LOCAL_THUNK_ALIAS_P, use_thunk puts the thunk
16376 into the same section as the target function. In that case
16377 we must return target's name. */
16378 tree target = THUNK_TARGET (decl);
16379 if (TARGET_USE_LOCAL_THUNK_ALIAS_P (target)
16380 && DECL_SECTION_NAME (target) != NULL
16381 && DECL_ONE_ONLY (target))
16382 decl = target;
16383 else
16384 break;
16385 }
16386 }
16387
16388 return decl;
16389 }
16390
16391 /* Returns the return type for FN as written by the user, which may include
16392 a placeholder for a deduced return type. */
16393
16394 tree
fndecl_declared_return_type(tree fn)16395 fndecl_declared_return_type (tree fn)
16396 {
16397 fn = STRIP_TEMPLATE (fn);
16398 if (FNDECL_USED_AUTO (fn))
16399 {
16400 struct language_function *f = NULL;
16401 if (DECL_STRUCT_FUNCTION (fn))
16402 f = DECL_STRUCT_FUNCTION (fn)->language;
16403 if (f == NULL)
16404 f = DECL_SAVED_FUNCTION_DATA (fn);
16405 return f->x_auto_return_pattern;
16406 }
16407 return TREE_TYPE (TREE_TYPE (fn));
16408 }
16409
16410 /* Returns true iff DECL is a variable or function declared with an auto type
16411 that has not yet been deduced to a real type. */
16412
16413 bool
undeduced_auto_decl(tree decl)16414 undeduced_auto_decl (tree decl)
16415 {
16416 if (cxx_dialect < cxx11)
16417 return false;
16418 return ((VAR_OR_FUNCTION_DECL_P (decl)
16419 || TREE_CODE (decl) == TEMPLATE_DECL)
16420 && type_uses_auto (TREE_TYPE (decl)));
16421 }
16422
16423 /* Complain if DECL has an undeduced return type. */
16424
16425 bool
require_deduced_type(tree decl,tsubst_flags_t complain)16426 require_deduced_type (tree decl, tsubst_flags_t complain)
16427 {
16428 if (undeduced_auto_decl (decl))
16429 {
16430 if (complain & tf_error)
16431 error ("use of %qD before deduction of %<auto%>", decl);
16432 return false;
16433 }
16434 return true;
16435 }
16436
16437 #include "gt-cp-decl.h"
16438