1 /* Process declarations and variables for -*- C++ -*- compiler.
2 Copyright (C) 1988-2020 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 #include "gcc-rich-location.h"
55 #include "langhooks.h"
56 #include "omp-general.h"
57
58 /* Possible cases of bad specifiers type used by bad_specifiers. */
59 enum bad_spec_place {
60 BSP_VAR, /* variable */
61 BSP_PARM, /* parameter */
62 BSP_TYPE, /* type */
63 BSP_FIELD /* field */
64 };
65
66 static const char *redeclaration_error_message (tree, tree);
67
68 static int decl_jump_unsafe (tree);
69 static void require_complete_types_for_parms (tree);
70 static tree grok_reference_init (tree, tree, tree, int);
71 static tree grokvardecl (tree, tree, tree, const cp_decl_specifier_seq *,
72 int, int, int, bool, int, tree, location_t);
73 static void check_static_variable_definition (tree, tree);
74 static void record_unknown_type (tree, const char *);
75 static int member_function_or_else (tree, tree, enum overload_flags);
76 static tree local_variable_p_walkfn (tree *, int *, void *);
77 static const char *tag_name (enum tag_types);
78 static tree lookup_and_check_tag (enum tag_types, tree, tag_scope, bool);
79 static void maybe_deduce_size_from_array_init (tree, tree);
80 static void layout_var_decl (tree);
81 static tree check_initializer (tree, tree, int, vec<tree, va_gc> **);
82 static void make_rtl_for_nonlocal_decl (tree, tree, const char *);
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, location_t);
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 static location_t smallest_type_location (const cp_decl_specifier_seq*);
104
105 /* The following symbols are subsumed in the cp_global_trees array, and
106 listed here individually for documentation purposes.
107
108 C++ extensions
109 tree wchar_decl_node;
110
111 tree vtable_entry_type;
112 tree delta_type_node;
113 tree __t_desc_type_node;
114
115 tree class_type_node;
116 tree unknown_type_node;
117
118 Array type `vtable_entry_type[]'
119
120 tree vtbl_type_node;
121 tree vtbl_ptr_type_node;
122
123 Namespaces,
124
125 tree std_node;
126 tree abi_node;
127
128 A FUNCTION_DECL which can call `abort'. Not necessarily the
129 one that the user will declare, but sufficient to be called
130 by routines that want to abort the program.
131
132 tree abort_fndecl;
133
134 Used by RTTI
135 tree type_info_type_node, tinfo_decl_id, tinfo_decl_type;
136 tree tinfo_var_id; */
137
138 tree cp_global_trees[CPTI_MAX];
139
140 /* A list of objects which have constructors or destructors
141 which reside in the global scope. The decl is stored in
142 the TREE_VALUE slot and the initializer is stored
143 in the TREE_PURPOSE slot. */
144 tree static_aggregates;
145
146 /* Like static_aggregates, but for thread_local variables. */
147 tree tls_aggregates;
148
149 /* -- end of C++ */
150
151 /* A node for the integer constant 2. */
152
153 tree integer_two_node;
154
155 /* vector of static decls. */
156 vec<tree, va_gc> *static_decls;
157
158 /* vector of keyed classes. */
159 vec<tree, va_gc> *keyed_classes;
160
161 /* Used only for jumps to as-yet undefined labels, since jumps to
162 defined labels can have their validity checked immediately. */
163
164 struct GTY((chain_next ("%h.next"))) named_label_use_entry {
165 struct named_label_use_entry *next;
166 /* The binding level to which this entry is *currently* attached.
167 This is initially the binding level in which the goto appeared,
168 but is modified as scopes are closed. */
169 cp_binding_level *binding_level;
170 /* The head of the names list that was current when the goto appeared,
171 or the inner scope popped. These are the decls that will *not* be
172 skipped when jumping to the label. */
173 tree names_in_scope;
174 /* The location of the goto, for error reporting. */
175 location_t o_goto_locus;
176 /* True if an OpenMP structured block scope has been closed since
177 the goto appeared. This means that the branch from the label will
178 illegally exit an OpenMP scope. */
179 bool in_omp_scope;
180 };
181
182 /* A list of all LABEL_DECLs in the function that have names. Here so
183 we can clear out their names' definitions at the end of the
184 function, and so we can check the validity of jumps to these labels. */
185
186 struct GTY((for_user)) named_label_entry {
187
188 tree name; /* Name of decl. */
189
190 tree label_decl; /* LABEL_DECL, unless deleted local label. */
191
192 named_label_entry *outer; /* Outer shadowed chain. */
193
194 /* The binding level to which the label is *currently* attached.
195 This is initially set to the binding level in which the label
196 is defined, but is modified as scopes are closed. */
197 cp_binding_level *binding_level;
198
199 /* The head of the names list that was current when the label was
200 defined, or the inner scope popped. These are the decls that will
201 be skipped when jumping to the label. */
202 tree names_in_scope;
203
204 /* A vector of all decls from all binding levels that would be
205 crossed by a backward branch to the label. */
206 vec<tree, va_gc> *bad_decls;
207
208 /* A list of uses of the label, before the label is defined. */
209 named_label_use_entry *uses;
210
211 /* The following bits are set after the label is defined, and are
212 updated as scopes are popped. They indicate that a jump to the
213 label will illegally enter a scope of the given flavor. */
214 bool in_try_scope;
215 bool in_catch_scope;
216 bool in_omp_scope;
217 bool in_transaction_scope;
218 bool in_constexpr_if;
219 };
220
221 #define named_labels cp_function_chain->x_named_labels
222
223 /* The number of function bodies which we are currently processing.
224 (Zero if we are at namespace scope, one inside the body of a
225 function, two inside the body of a function in a local class, etc.) */
226 int function_depth;
227
228 /* Whether the exception-specifier is part of a function type (i.e. C++17). */
229 bool flag_noexcept_type;
230
231 /* States indicating how grokdeclarator() should handle declspecs marked
232 with __attribute__((deprecated)). An object declared as
233 __attribute__((deprecated)) suppresses warnings of uses of other
234 deprecated items. */
235 enum deprecated_states deprecated_state = DEPRECATED_NORMAL;
236
237
238 /* A list of VAR_DECLs whose type was incomplete at the time the
239 variable was declared. */
240
241 struct GTY(()) incomplete_var {
242 tree decl;
243 tree incomplete_type;
244 };
245
246
247 static GTY(()) vec<incomplete_var, va_gc> *incomplete_vars;
248
249 /* Returns the kind of template specialization we are currently
250 processing, given that it's declaration contained N_CLASS_SCOPES
251 explicit scope qualifications. */
252
253 tmpl_spec_kind
current_tmpl_spec_kind(int n_class_scopes)254 current_tmpl_spec_kind (int n_class_scopes)
255 {
256 int n_template_parm_scopes = 0;
257 int seen_specialization_p = 0;
258 int innermost_specialization_p = 0;
259 cp_binding_level *b;
260
261 /* Scan through the template parameter scopes. */
262 for (b = current_binding_level;
263 b->kind == sk_template_parms;
264 b = b->level_chain)
265 {
266 /* If we see a specialization scope inside a parameter scope,
267 then something is wrong. That corresponds to a declaration
268 like:
269
270 template <class T> template <> ...
271
272 which is always invalid since [temp.expl.spec] forbids the
273 specialization of a class member template if the enclosing
274 class templates are not explicitly specialized as well. */
275 if (b->explicit_spec_p)
276 {
277 if (n_template_parm_scopes == 0)
278 innermost_specialization_p = 1;
279 else
280 seen_specialization_p = 1;
281 }
282 else if (seen_specialization_p == 1)
283 return tsk_invalid_member_spec;
284
285 ++n_template_parm_scopes;
286 }
287
288 /* Handle explicit instantiations. */
289 if (processing_explicit_instantiation)
290 {
291 if (n_template_parm_scopes != 0)
292 /* We've seen a template parameter list during an explicit
293 instantiation. For example:
294
295 template <class T> template void f(int);
296
297 This is erroneous. */
298 return tsk_invalid_expl_inst;
299 else
300 return tsk_expl_inst;
301 }
302
303 if (n_template_parm_scopes < n_class_scopes)
304 /* We've not seen enough template headers to match all the
305 specialized classes present. For example:
306
307 template <class T> void R<T>::S<T>::f(int);
308
309 This is invalid; there needs to be one set of template
310 parameters for each class. */
311 return tsk_insufficient_parms;
312 else if (n_template_parm_scopes == n_class_scopes)
313 /* We're processing a non-template declaration (even though it may
314 be a member of a template class.) For example:
315
316 template <class T> void S<T>::f(int);
317
318 The `class T' matches the `S<T>', leaving no template headers
319 corresponding to the `f'. */
320 return tsk_none;
321 else if (n_template_parm_scopes > n_class_scopes + 1)
322 /* We've got too many template headers. For example:
323
324 template <> template <class T> void f (T);
325
326 There need to be more enclosing classes. */
327 return tsk_excessive_parms;
328 else
329 /* This must be a template. It's of the form:
330
331 template <class T> template <class U> void S<T>::f(U);
332
333 This is a specialization if the innermost level was a
334 specialization; otherwise it's just a definition of the
335 template. */
336 return innermost_specialization_p ? tsk_expl_spec : tsk_template;
337 }
338
339 /* Exit the current scope. */
340
341 void
finish_scope(void)342 finish_scope (void)
343 {
344 poplevel (0, 0, 0);
345 }
346
347 /* When a label goes out of scope, check to see if that label was used
348 in a valid manner, and issue any appropriate warnings or errors. */
349
350 static void
check_label_used(tree label)351 check_label_used (tree label)
352 {
353 if (!processing_template_decl)
354 {
355 if (DECL_INITIAL (label) == NULL_TREE)
356 {
357 location_t location;
358
359 error ("label %q+D used but not defined", label);
360 location = input_location;
361 /* FIXME want (LOCATION_FILE (input_location), (line)0) */
362 /* Avoid crashing later. */
363 define_label (location, DECL_NAME (label));
364 }
365 else
366 warn_for_unused_label (label);
367 }
368 }
369
370 /* Helper function to sort named label entries in a vector by DECL_UID. */
371
372 static int
sort_labels(const void * a,const void * b)373 sort_labels (const void *a, const void *b)
374 {
375 tree label1 = *(tree const *) a;
376 tree label2 = *(tree const *) b;
377
378 /* DECL_UIDs can never be equal. */
379 return DECL_UID (label1) > DECL_UID (label2) ? -1 : +1;
380 }
381
382 /* At the end of a function, all labels declared within the function
383 go out of scope. BLOCK is the top-level block for the
384 function. */
385
386 static void
pop_labels(tree block)387 pop_labels (tree block)
388 {
389 if (!named_labels)
390 return;
391
392 /* We need to add the labels to the block chain, so debug
393 information is emitted. But, we want the order to be stable so
394 need to sort them first. Otherwise the debug output could be
395 randomly ordered. I guess it's mostly stable, unless the hash
396 table implementation changes. */
397 auto_vec<tree, 32> labels (named_labels->elements ());
398 hash_table<named_label_hash>::iterator end (named_labels->end ());
399 for (hash_table<named_label_hash>::iterator iter
400 (named_labels->begin ()); iter != end; ++iter)
401 {
402 named_label_entry *ent = *iter;
403
404 gcc_checking_assert (!ent->outer);
405 if (ent->label_decl)
406 labels.quick_push (ent->label_decl);
407 ggc_free (ent);
408 }
409 named_labels = NULL;
410 labels.qsort (sort_labels);
411
412 while (labels.length ())
413 {
414 tree label = labels.pop ();
415
416 DECL_CHAIN (label) = BLOCK_VARS (block);
417 BLOCK_VARS (block) = label;
418
419 check_label_used (label);
420 }
421 }
422
423 /* At the end of a block with local labels, restore the outer definition. */
424
425 static void
pop_local_label(tree id,tree label)426 pop_local_label (tree id, tree label)
427 {
428 check_label_used (label);
429 named_label_entry **slot = named_labels->find_slot_with_hash
430 (id, IDENTIFIER_HASH_VALUE (id), NO_INSERT);
431 named_label_entry *ent = *slot;
432
433 if (ent->outer)
434 ent = ent->outer;
435 else
436 {
437 ent = ggc_cleared_alloc<named_label_entry> ();
438 ent->name = id;
439 }
440 *slot = ent;
441 }
442
443 /* The following two routines are used to interface to Objective-C++.
444 The binding level is purposely treated as an opaque type. */
445
446 void *
objc_get_current_scope(void)447 objc_get_current_scope (void)
448 {
449 return current_binding_level;
450 }
451
452 /* The following routine is used by the NeXT-style SJLJ exceptions;
453 variables get marked 'volatile' so as to not be clobbered by
454 _setjmp()/_longjmp() calls. All variables in the current scope,
455 as well as parent scopes up to (but not including) ENCLOSING_BLK
456 shall be thusly marked. */
457
458 void
objc_mark_locals_volatile(void * enclosing_blk)459 objc_mark_locals_volatile (void *enclosing_blk)
460 {
461 cp_binding_level *scope;
462
463 for (scope = current_binding_level;
464 scope && scope != enclosing_blk;
465 scope = scope->level_chain)
466 {
467 tree decl;
468
469 for (decl = scope->names; decl; decl = TREE_CHAIN (decl))
470 objc_volatilize_decl (decl);
471
472 /* Do not climb up past the current function. */
473 if (scope->kind == sk_function_parms)
474 break;
475 }
476 }
477
478 /* True if B is the level for the condition of a constexpr if. */
479
480 static bool
level_for_constexpr_if(cp_binding_level * b)481 level_for_constexpr_if (cp_binding_level *b)
482 {
483 return (b->kind == sk_cond && b->this_entity
484 && TREE_CODE (b->this_entity) == IF_STMT
485 && IF_STMT_CONSTEXPR_P (b->this_entity));
486 }
487
488 /* Update data for defined and undefined labels when leaving a scope. */
489
490 int
poplevel_named_label_1(named_label_entry ** slot,cp_binding_level * bl)491 poplevel_named_label_1 (named_label_entry **slot, cp_binding_level *bl)
492 {
493 named_label_entry *ent = *slot;
494 cp_binding_level *obl = bl->level_chain;
495
496 if (ent->binding_level == bl)
497 {
498 tree decl;
499
500 /* ENT->NAMES_IN_SCOPE may contain a mixture of DECLs and
501 TREE_LISTs representing OVERLOADs, so be careful. */
502 for (decl = ent->names_in_scope; decl; decl = (DECL_P (decl)
503 ? DECL_CHAIN (decl)
504 : TREE_CHAIN (decl)))
505 if (decl_jump_unsafe (decl))
506 vec_safe_push (ent->bad_decls, decl);
507
508 ent->binding_level = obl;
509 ent->names_in_scope = obl->names;
510 switch (bl->kind)
511 {
512 case sk_try:
513 ent->in_try_scope = true;
514 break;
515 case sk_catch:
516 ent->in_catch_scope = true;
517 break;
518 case sk_omp:
519 ent->in_omp_scope = true;
520 break;
521 case sk_transaction:
522 ent->in_transaction_scope = true;
523 break;
524 case sk_block:
525 if (level_for_constexpr_if (bl->level_chain))
526 ent->in_constexpr_if = true;
527 break;
528 default:
529 break;
530 }
531 }
532 else if (ent->uses)
533 {
534 struct named_label_use_entry *use;
535
536 for (use = ent->uses; use ; use = use->next)
537 if (use->binding_level == bl)
538 {
539 use->binding_level = obl;
540 use->names_in_scope = obl->names;
541 if (bl->kind == sk_omp)
542 use->in_omp_scope = true;
543 }
544 }
545
546 return 1;
547 }
548
549 /* Saved errorcount to avoid -Wunused-but-set-{parameter,variable} warnings
550 when errors were reported, except for -Werror-unused-but-set-*. */
551 static int unused_but_set_errorcount;
552
553 /* Exit a binding level.
554 Pop the level off, and restore the state of the identifier-decl mappings
555 that were in effect when this level was entered.
556
557 If KEEP == 1, this level had explicit declarations, so
558 and create a "block" (a BLOCK node) for the level
559 to record its declarations and subblocks for symbol table output.
560
561 If FUNCTIONBODY is nonzero, this level is the body of a function,
562 so create a block as if KEEP were set and also clear out all
563 label names.
564
565 If REVERSE is nonzero, reverse the order of decls before putting
566 them into the BLOCK. */
567
568 tree
poplevel(int keep,int reverse,int functionbody)569 poplevel (int keep, int reverse, int functionbody)
570 {
571 tree link;
572 /* The chain of decls was accumulated in reverse order.
573 Put it into forward order, just for cleanliness. */
574 tree decls;
575 tree subblocks;
576 tree block;
577 tree decl;
578 scope_kind kind;
579
580 bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
581 restart:
582
583 block = NULL_TREE;
584
585 gcc_assert (current_binding_level->kind != sk_class
586 && current_binding_level->kind != sk_namespace);
587
588 if (current_binding_level->kind == sk_cleanup)
589 functionbody = 0;
590 subblocks = functionbody >= 0 ? current_binding_level->blocks : 0;
591
592 gcc_assert (!vec_safe_length (current_binding_level->class_shadowed));
593
594 /* We used to use KEEP == 2 to indicate that the new block should go
595 at the beginning of the list of blocks at this binding level,
596 rather than the end. This hack is no longer used. */
597 gcc_assert (keep == 0 || keep == 1);
598
599 if (current_binding_level->keep)
600 keep = 1;
601
602 /* Any uses of undefined labels, and any defined labels, now operate
603 under constraints of next binding contour. */
604 if (cfun && !functionbody && named_labels)
605 named_labels->traverse<cp_binding_level *, poplevel_named_label_1>
606 (current_binding_level);
607
608 /* Get the decls in the order they were written.
609 Usually current_binding_level->names is in reverse order.
610 But parameter decls were previously put in forward order. */
611
612 decls = current_binding_level->names;
613 if (reverse)
614 {
615 decls = nreverse (decls);
616 current_binding_level->names = decls;
617 }
618
619 /* If there were any declarations or structure tags in that level,
620 or if this level is a function body,
621 create a BLOCK to record them for the life of this function. */
622 block = NULL_TREE;
623 /* Avoid function body block if possible. */
624 if (functionbody && subblocks && BLOCK_CHAIN (subblocks) == NULL_TREE)
625 keep = 0;
626 else if (keep == 1 || functionbody)
627 block = make_node (BLOCK);
628 if (block != NULL_TREE)
629 {
630 BLOCK_VARS (block) = decls;
631 BLOCK_SUBBLOCKS (block) = subblocks;
632 }
633
634 /* In each subblock, record that this is its superior. */
635 if (keep >= 0)
636 for (link = subblocks; link; link = BLOCK_CHAIN (link))
637 BLOCK_SUPERCONTEXT (link) = block;
638
639 /* Before we remove the declarations first check for unused variables. */
640 if ((warn_unused_variable || warn_unused_but_set_variable)
641 && current_binding_level->kind != sk_template_parms
642 && !processing_template_decl)
643 for (tree d = get_local_decls (); d; d = TREE_CHAIN (d))
644 {
645 /* There are cases where D itself is a TREE_LIST. See in
646 push_local_binding where the list of decls returned by
647 getdecls is built. */
648 decl = TREE_CODE (d) == TREE_LIST ? TREE_VALUE (d) : d;
649
650 tree type = TREE_TYPE (decl);
651 if (VAR_P (decl)
652 && (! TREE_USED (decl) || !DECL_READ_P (decl))
653 && ! DECL_IN_SYSTEM_HEADER (decl)
654 /* For structured bindings, consider only real variables, not
655 subobjects. */
656 && (DECL_DECOMPOSITION_P (decl) ? !DECL_DECOMP_BASE (decl)
657 : (DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)))
658 && type != error_mark_node
659 && (!CLASS_TYPE_P (type)
660 || !TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
661 || lookup_attribute ("warn_unused",
662 TYPE_ATTRIBUTES (TREE_TYPE (decl)))))
663 {
664 if (! TREE_USED (decl))
665 {
666 if (!DECL_NAME (decl) && DECL_DECOMPOSITION_P (decl))
667 warning_at (DECL_SOURCE_LOCATION (decl),
668 OPT_Wunused_variable,
669 "unused structured binding declaration");
670 else
671 warning_at (DECL_SOURCE_LOCATION (decl),
672 OPT_Wunused_variable, "unused variable %qD", decl);
673 }
674 else if (DECL_CONTEXT (decl) == current_function_decl
675 // For -Wunused-but-set-variable leave references alone.
676 && !TYPE_REF_P (TREE_TYPE (decl))
677 && errorcount == unused_but_set_errorcount)
678 {
679 if (!DECL_NAME (decl) && DECL_DECOMPOSITION_P (decl))
680 warning_at (DECL_SOURCE_LOCATION (decl),
681 OPT_Wunused_but_set_variable, "structured "
682 "binding declaration set but not used");
683 else
684 warning_at (DECL_SOURCE_LOCATION (decl),
685 OPT_Wunused_but_set_variable,
686 "variable %qD set but not used", decl);
687 unused_but_set_errorcount = errorcount;
688 }
689 }
690 }
691
692 /* Remove declarations for all the DECLs in this level. */
693 for (link = decls; link; link = TREE_CHAIN (link))
694 {
695 decl = TREE_CODE (link) == TREE_LIST ? TREE_VALUE (link) : link;
696 tree name = OVL_NAME (decl);
697
698 /* Remove the binding. */
699 if (TREE_CODE (decl) == LABEL_DECL)
700 pop_local_label (name, decl);
701 else
702 pop_local_binding (name, decl);
703 }
704
705 /* Restore the IDENTIFIER_TYPE_VALUEs. */
706 for (link = current_binding_level->type_shadowed;
707 link; link = TREE_CHAIN (link))
708 SET_IDENTIFIER_TYPE_VALUE (TREE_PURPOSE (link), TREE_VALUE (link));
709
710 /* There may be OVERLOADs (wrapped in TREE_LISTs) on the BLOCK_VARs
711 list if a `using' declaration put them there. The debugging
712 back ends won't understand OVERLOAD, so we remove them here.
713 Because the BLOCK_VARS are (temporarily) shared with
714 CURRENT_BINDING_LEVEL->NAMES we must do this fixup after we have
715 popped all the bindings. Also remove undeduced 'auto' decls,
716 which LTO doesn't understand, and can't have been used by anything. */
717 if (block)
718 {
719 tree* d;
720
721 for (d = &BLOCK_VARS (block); *d; )
722 {
723 if (TREE_CODE (*d) == TREE_LIST
724 || (!processing_template_decl
725 && undeduced_auto_decl (*d)))
726 *d = TREE_CHAIN (*d);
727 else
728 d = &DECL_CHAIN (*d);
729 }
730 }
731
732 /* If the level being exited is the top level of a function,
733 check over all the labels. */
734 if (functionbody)
735 {
736 if (block)
737 {
738 /* Since this is the top level block of a function, the vars are
739 the function's parameters. Don't leave them in the BLOCK
740 because they are found in the FUNCTION_DECL instead. */
741 BLOCK_VARS (block) = 0;
742 pop_labels (block);
743 }
744 else
745 pop_labels (subblocks);
746 }
747
748 kind = current_binding_level->kind;
749 if (kind == sk_cleanup)
750 {
751 tree stmt;
752
753 /* If this is a temporary binding created for a cleanup, then we'll
754 have pushed a statement list level. Pop that, create a new
755 BIND_EXPR for the block, and insert it into the stream. */
756 stmt = pop_stmt_list (current_binding_level->statement_list);
757 stmt = c_build_bind_expr (input_location, block, stmt);
758 add_stmt (stmt);
759 }
760
761 leave_scope ();
762 if (functionbody)
763 {
764 /* The current function is being defined, so its DECL_INITIAL
765 should be error_mark_node. */
766 gcc_assert (DECL_INITIAL (current_function_decl) == error_mark_node);
767 DECL_INITIAL (current_function_decl) = block ? block : subblocks;
768 if (subblocks)
769 {
770 if (FUNCTION_NEEDS_BODY_BLOCK (current_function_decl))
771 {
772 if (BLOCK_SUBBLOCKS (subblocks))
773 BLOCK_OUTER_CURLY_BRACE_P (BLOCK_SUBBLOCKS (subblocks)) = 1;
774 }
775 else
776 BLOCK_OUTER_CURLY_BRACE_P (subblocks) = 1;
777 }
778 }
779 else if (block)
780 current_binding_level->blocks
781 = block_chainon (current_binding_level->blocks, block);
782
783 /* If we did not make a block for the level just exited,
784 any blocks made for inner levels
785 (since they cannot be recorded as subblocks in that level)
786 must be carried forward so they will later become subblocks
787 of something else. */
788 else if (subblocks)
789 current_binding_level->blocks
790 = block_chainon (current_binding_level->blocks, subblocks);
791
792 /* Each and every BLOCK node created here in `poplevel' is important
793 (e.g. for proper debugging information) so if we created one
794 earlier, mark it as "used". */
795 if (block)
796 TREE_USED (block) = 1;
797
798 /* All temporary bindings created for cleanups are popped silently. */
799 if (kind == sk_cleanup)
800 goto restart;
801
802 timevar_cond_stop (TV_NAME_LOOKUP, subtime);
803 return block;
804 }
805
806 /* Call wrapup_globals_declarations for the globals in NAMESPACE. */
807 /* Diagnose odr-used extern inline variables without definitions
808 in the current TU. */
809
810 int
wrapup_namespace_globals()811 wrapup_namespace_globals ()
812 {
813 if (vec<tree, va_gc> *statics = static_decls)
814 {
815 tree decl;
816 unsigned int i;
817 FOR_EACH_VEC_ELT (*statics, i, decl)
818 {
819 if (warn_unused_function
820 && TREE_CODE (decl) == FUNCTION_DECL
821 && DECL_INITIAL (decl) == 0
822 && DECL_EXTERNAL (decl)
823 && !TREE_PUBLIC (decl)
824 && !DECL_ARTIFICIAL (decl)
825 && !DECL_FRIEND_PSEUDO_TEMPLATE_INSTANTIATION (decl)
826 && !TREE_NO_WARNING (decl))
827 warning_at (DECL_SOURCE_LOCATION (decl),
828 OPT_Wunused_function,
829 "%qF declared %<static%> but never defined", decl);
830
831 if (VAR_P (decl)
832 && DECL_EXTERNAL (decl)
833 && DECL_INLINE_VAR_P (decl)
834 && DECL_ODR_USED (decl))
835 error_at (DECL_SOURCE_LOCATION (decl),
836 "odr-used inline variable %qD is not defined", decl);
837 }
838
839 /* Clear out the list, so we don't rescan next time. */
840 static_decls = NULL;
841
842 /* Write out any globals that need to be output. */
843 return wrapup_global_declarations (statics->address (),
844 statics->length ());
845 }
846 return 0;
847 }
848
849 /* In C++, you don't have to write `struct S' to refer to `S'; you
850 can just use `S'. We accomplish this by creating a TYPE_DECL as
851 if the user had written `typedef struct S S'. Create and return
852 the TYPE_DECL for TYPE. */
853
854 tree
create_implicit_typedef(tree name,tree type)855 create_implicit_typedef (tree name, tree type)
856 {
857 tree decl;
858
859 decl = build_decl (input_location, TYPE_DECL, name, type);
860 DECL_ARTIFICIAL (decl) = 1;
861 /* There are other implicit type declarations, like the one *within*
862 a class that allows you to write `S::S'. We must distinguish
863 amongst these. */
864 SET_DECL_IMPLICIT_TYPEDEF_P (decl);
865 TYPE_NAME (type) = decl;
866 TYPE_STUB_DECL (type) = decl;
867
868 return decl;
869 }
870
871 /* Function-scope local entities that need discriminators. Each entry
872 is a {decl,name} pair. VAR_DECLs for anon unions get their name
873 smashed, so we cannot rely on DECL_NAME. */
874
875 static GTY((deletable)) vec<tree, va_gc> *local_entities;
876
877 /* Determine the mangling discriminator of local DECL. There are
878 generally very few of these in any particular function. */
879
880 void
determine_local_discriminator(tree decl)881 determine_local_discriminator (tree decl)
882 {
883 bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
884 retrofit_lang_decl (decl);
885 tree ctx = DECL_CONTEXT (decl);
886 tree name = (TREE_CODE (decl) == TYPE_DECL
887 && TYPE_UNNAMED_P (TREE_TYPE (decl))
888 ? NULL_TREE : DECL_NAME (decl));
889 size_t nelts = vec_safe_length (local_entities);
890 for (size_t i = 0; i < nelts; i += 2)
891 {
892 tree *pair = &(*local_entities)[i];
893 tree d = pair[0];
894 tree n = pair[1];
895 gcc_checking_assert (d != decl);
896 if (name == n
897 && TREE_CODE (decl) == TREE_CODE (d)
898 && ctx == DECL_CONTEXT (d))
899 {
900 tree disc = integer_one_node;
901 if (DECL_DISCRIMINATOR (d))
902 disc = build_int_cst (TREE_TYPE (disc),
903 TREE_INT_CST_LOW (DECL_DISCRIMINATOR (d)) + 1);
904 DECL_DISCRIMINATOR (decl) = disc;
905 /* Replace the saved decl. */
906 pair[0] = decl;
907 decl = NULL_TREE;
908 break;
909 }
910 }
911
912 if (decl)
913 {
914 vec_safe_reserve (local_entities, 2);
915 local_entities->quick_push (decl);
916 local_entities->quick_push (name);
917 }
918
919 timevar_cond_stop (TV_NAME_LOOKUP, subtime);
920 }
921
922
923
924 /* Returns true if functions FN1 and FN2 have equivalent trailing
925 requires clauses. */
926
927 static bool
function_requirements_equivalent_p(tree newfn,tree oldfn)928 function_requirements_equivalent_p (tree newfn, tree oldfn)
929 {
930 /* In the concepts TS, the combined constraints are compared. */
931 if (cxx_dialect < cxx2a)
932 {
933 tree ci1 = get_constraints (oldfn);
934 tree ci2 = get_constraints (newfn);
935 tree req1 = ci1 ? CI_ASSOCIATED_CONSTRAINTS (ci1) : NULL_TREE;
936 tree req2 = ci2 ? CI_ASSOCIATED_CONSTRAINTS (ci2) : NULL_TREE;
937 return cp_tree_equal (req1, req2);
938 }
939
940 /* Compare only trailing requirements. */
941 tree reqs1 = get_trailing_function_requirements (newfn);
942 tree reqs2 = get_trailing_function_requirements (oldfn);
943 if ((reqs1 != NULL_TREE) != (reqs2 != NULL_TREE))
944 return false;
945 reqs1 = maybe_substitute_reqs_for (reqs1, newfn);
946 reqs2 = maybe_substitute_reqs_for (reqs2, oldfn);
947 return cp_tree_equal (reqs1, reqs2);
948 }
949
950 /* Subroutine of duplicate_decls: return truthvalue of whether
951 or not types of these decls match.
952
953 For C++, we must compare the parameter list so that `int' can match
954 `int&' in a parameter position, but `int&' is not confused with
955 `const int&'. */
956
957 int
decls_match(tree newdecl,tree olddecl,bool record_versions)958 decls_match (tree newdecl, tree olddecl, bool record_versions /* = true */)
959 {
960 int types_match;
961
962 if (newdecl == olddecl)
963 return 1;
964
965 if (TREE_CODE (newdecl) != TREE_CODE (olddecl))
966 /* If the two DECLs are not even the same kind of thing, we're not
967 interested in their types. */
968 return 0;
969
970 gcc_assert (DECL_P (newdecl));
971
972 if (TREE_CODE (newdecl) == FUNCTION_DECL)
973 {
974 tree f1 = TREE_TYPE (newdecl);
975 tree f2 = TREE_TYPE (olddecl);
976 tree p1 = TYPE_ARG_TYPES (f1);
977 tree p2 = TYPE_ARG_TYPES (f2);
978 tree r2;
979
980 /* Specializations of different templates are different functions
981 even if they have the same type. */
982 tree t1 = (DECL_USE_TEMPLATE (newdecl)
983 ? DECL_TI_TEMPLATE (newdecl)
984 : NULL_TREE);
985 tree t2 = (DECL_USE_TEMPLATE (olddecl)
986 ? DECL_TI_TEMPLATE (olddecl)
987 : NULL_TREE);
988 if (t1 != t2)
989 return 0;
990
991 if (CP_DECL_CONTEXT (newdecl) != CP_DECL_CONTEXT (olddecl)
992 && ! (DECL_EXTERN_C_P (newdecl)
993 && DECL_EXTERN_C_P (olddecl)))
994 return 0;
995
996 /* A new declaration doesn't match a built-in one unless it
997 is also extern "C". */
998 if (DECL_IS_BUILTIN (olddecl)
999 && DECL_EXTERN_C_P (olddecl) && !DECL_EXTERN_C_P (newdecl))
1000 return 0;
1001
1002 if (TREE_CODE (f1) != TREE_CODE (f2))
1003 return 0;
1004
1005 /* A declaration with deduced return type should use its pre-deduction
1006 type for declaration matching. */
1007 r2 = fndecl_declared_return_type (olddecl);
1008
1009 if (same_type_p (TREE_TYPE (f1), r2))
1010 {
1011 if (!prototype_p (f2) && DECL_EXTERN_C_P (olddecl)
1012 && fndecl_built_in_p (olddecl))
1013 {
1014 types_match = self_promoting_args_p (p1);
1015 if (p1 == void_list_node)
1016 TREE_TYPE (newdecl) = TREE_TYPE (olddecl);
1017 }
1018 else
1019 types_match =
1020 compparms (p1, p2)
1021 && type_memfn_rqual (f1) == type_memfn_rqual (f2)
1022 && (TYPE_ATTRIBUTES (TREE_TYPE (newdecl)) == NULL_TREE
1023 || comp_type_attributes (TREE_TYPE (newdecl),
1024 TREE_TYPE (olddecl)) != 0);
1025 }
1026 else
1027 types_match = 0;
1028
1029 /* Two function declarations match if either has a requires-clause
1030 then both have a requires-clause and their constraints-expressions
1031 are equivalent. */
1032 if (types_match && flag_concepts)
1033 types_match = function_requirements_equivalent_p (newdecl, olddecl);
1034
1035 /* The decls dont match if they correspond to two different versions
1036 of the same function. Disallow extern "C" functions to be
1037 versions for now. */
1038 if (types_match
1039 && !DECL_EXTERN_C_P (newdecl)
1040 && !DECL_EXTERN_C_P (olddecl)
1041 && record_versions
1042 && maybe_version_functions (newdecl, olddecl,
1043 (!DECL_FUNCTION_VERSIONED (newdecl)
1044 || !DECL_FUNCTION_VERSIONED (olddecl))))
1045 return 0;
1046 }
1047 else if (TREE_CODE (newdecl) == TEMPLATE_DECL)
1048 {
1049 if (!template_heads_equivalent_p (newdecl, olddecl))
1050 return 0;
1051
1052 tree oldres = DECL_TEMPLATE_RESULT (olddecl);
1053 tree newres = DECL_TEMPLATE_RESULT (newdecl);
1054
1055 if (TREE_CODE (newres) != TREE_CODE (oldres))
1056 return 0;
1057
1058 /* Two template types match if they are the same. Otherwise, compare
1059 the underlying declarations. */
1060 if (TREE_CODE (newres) == TYPE_DECL)
1061 types_match = same_type_p (TREE_TYPE (newres), TREE_TYPE (oldres));
1062 else
1063 types_match = decls_match (newres, oldres);
1064 }
1065 else
1066 {
1067 /* Need to check scope for variable declaration (VAR_DECL).
1068 For typedef (TYPE_DECL), scope is ignored. */
1069 if (VAR_P (newdecl)
1070 && CP_DECL_CONTEXT (newdecl) != CP_DECL_CONTEXT (olddecl)
1071 /* [dcl.link]
1072 Two declarations for an object with C language linkage
1073 with the same name (ignoring the namespace that qualify
1074 it) that appear in different namespace scopes refer to
1075 the same object. */
1076 && !(DECL_EXTERN_C_P (olddecl) && DECL_EXTERN_C_P (newdecl)))
1077 return 0;
1078
1079 if (TREE_TYPE (newdecl) == error_mark_node)
1080 types_match = TREE_TYPE (olddecl) == error_mark_node;
1081 else if (TREE_TYPE (olddecl) == NULL_TREE)
1082 types_match = TREE_TYPE (newdecl) == NULL_TREE;
1083 else if (TREE_TYPE (newdecl) == NULL_TREE)
1084 types_match = 0;
1085 else
1086 types_match = comptypes (TREE_TYPE (newdecl),
1087 TREE_TYPE (olddecl),
1088 COMPARE_REDECLARATION);
1089 }
1090
1091 return types_match;
1092 }
1093
1094 /* NEWDECL and OLDDECL have identical signatures. If they are
1095 different versions adjust them and return true.
1096 If RECORD is set to true, record function versions. */
1097
1098 bool
maybe_version_functions(tree newdecl,tree olddecl,bool record)1099 maybe_version_functions (tree newdecl, tree olddecl, bool record)
1100 {
1101 if (!targetm.target_option.function_versions (newdecl, olddecl))
1102 return false;
1103
1104 if (!DECL_FUNCTION_VERSIONED (olddecl))
1105 {
1106 DECL_FUNCTION_VERSIONED (olddecl) = 1;
1107 if (DECL_ASSEMBLER_NAME_SET_P (olddecl))
1108 mangle_decl (olddecl);
1109 }
1110
1111 if (!DECL_FUNCTION_VERSIONED (newdecl))
1112 {
1113 DECL_FUNCTION_VERSIONED (newdecl) = 1;
1114 if (DECL_ASSEMBLER_NAME_SET_P (newdecl))
1115 mangle_decl (newdecl);
1116 }
1117
1118 if (record)
1119 cgraph_node::record_function_versions (olddecl, newdecl);
1120
1121 return true;
1122 }
1123
1124 /* If NEWDECL is `static' and an `extern' was seen previously,
1125 warn about it. OLDDECL is the previous declaration.
1126
1127 Note that this does not apply to the C++ case of declaring
1128 a variable `extern const' and then later `const'.
1129
1130 Don't complain about built-in functions, since they are beyond
1131 the user's control. */
1132
1133 void
warn_extern_redeclared_static(tree newdecl,tree olddecl)1134 warn_extern_redeclared_static (tree newdecl, tree olddecl)
1135 {
1136 if (TREE_CODE (newdecl) == TYPE_DECL
1137 || TREE_CODE (newdecl) == TEMPLATE_DECL
1138 || TREE_CODE (newdecl) == CONST_DECL
1139 || TREE_CODE (newdecl) == NAMESPACE_DECL)
1140 return;
1141
1142 /* Don't get confused by static member functions; that's a different
1143 use of `static'. */
1144 if (TREE_CODE (newdecl) == FUNCTION_DECL
1145 && DECL_STATIC_FUNCTION_P (newdecl))
1146 return;
1147
1148 /* If the old declaration was `static', or the new one isn't, then
1149 everything is OK. */
1150 if (DECL_THIS_STATIC (olddecl) || !DECL_THIS_STATIC (newdecl))
1151 return;
1152
1153 /* It's OK to declare a builtin function as `static'. */
1154 if (TREE_CODE (olddecl) == FUNCTION_DECL
1155 && DECL_ARTIFICIAL (olddecl))
1156 return;
1157
1158 auto_diagnostic_group d;
1159 if (permerror (DECL_SOURCE_LOCATION (newdecl),
1160 "%qD was declared %<extern%> and later %<static%>", newdecl))
1161 inform (DECL_SOURCE_LOCATION (olddecl),
1162 "previous declaration of %qD", olddecl);
1163 }
1164
1165 /* NEW_DECL is a redeclaration of OLD_DECL; both are functions or
1166 function templates. If their exception specifications do not
1167 match, issue a diagnostic. */
1168
1169 static void
check_redeclaration_exception_specification(tree new_decl,tree old_decl)1170 check_redeclaration_exception_specification (tree new_decl,
1171 tree old_decl)
1172 {
1173 tree new_exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (new_decl));
1174 tree old_exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (old_decl));
1175
1176 /* Two default specs are equivalent, don't force evaluation. */
1177 if (UNEVALUATED_NOEXCEPT_SPEC_P (new_exceptions)
1178 && UNEVALUATED_NOEXCEPT_SPEC_P (old_exceptions))
1179 return;
1180
1181 if (!type_dependent_expression_p (old_decl))
1182 {
1183 maybe_instantiate_noexcept (new_decl);
1184 maybe_instantiate_noexcept (old_decl);
1185 }
1186 new_exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (new_decl));
1187 old_exceptions = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (old_decl));
1188
1189 /* [except.spec]
1190
1191 If any declaration of a function has an exception-specification,
1192 all declarations, including the definition and an explicit
1193 specialization, of that function shall have an
1194 exception-specification with the same set of type-ids. */
1195 if (! DECL_IS_BUILTIN (old_decl)
1196 && !comp_except_specs (new_exceptions, old_exceptions, ce_normal))
1197 {
1198 const char *const msg
1199 = G_("declaration of %qF has a different exception specifier");
1200 bool complained = true;
1201 location_t new_loc = DECL_SOURCE_LOCATION (new_decl);
1202 auto_diagnostic_group d;
1203 if (DECL_IN_SYSTEM_HEADER (old_decl))
1204 complained = pedwarn (new_loc, OPT_Wsystem_headers, msg, new_decl);
1205 else if (!flag_exceptions)
1206 /* We used to silently permit mismatched eh specs with
1207 -fno-exceptions, so make them a pedwarn now. */
1208 complained = pedwarn (new_loc, OPT_Wpedantic, msg, new_decl);
1209 else
1210 error_at (new_loc, msg, new_decl);
1211 if (complained)
1212 inform (DECL_SOURCE_LOCATION (old_decl),
1213 "from previous declaration %qF", old_decl);
1214 }
1215 }
1216
1217 /* Return true if OLD_DECL and NEW_DECL agree on constexprness.
1218 Otherwise issue diagnostics. */
1219
1220 static bool
validate_constexpr_redeclaration(tree old_decl,tree new_decl)1221 validate_constexpr_redeclaration (tree old_decl, tree new_decl)
1222 {
1223 old_decl = STRIP_TEMPLATE (old_decl);
1224 new_decl = STRIP_TEMPLATE (new_decl);
1225 if (!VAR_OR_FUNCTION_DECL_P (old_decl)
1226 || !VAR_OR_FUNCTION_DECL_P (new_decl))
1227 return true;
1228 if (DECL_DECLARED_CONSTEXPR_P (old_decl)
1229 == DECL_DECLARED_CONSTEXPR_P (new_decl))
1230 {
1231 if (TREE_CODE (old_decl) != FUNCTION_DECL)
1232 return true;
1233 if (DECL_IMMEDIATE_FUNCTION_P (old_decl)
1234 == DECL_IMMEDIATE_FUNCTION_P (new_decl))
1235 return true;
1236 }
1237 if (TREE_CODE (old_decl) == FUNCTION_DECL)
1238 {
1239 if (fndecl_built_in_p (old_decl))
1240 {
1241 /* Hide a built-in declaration. */
1242 DECL_DECLARED_CONSTEXPR_P (old_decl)
1243 = DECL_DECLARED_CONSTEXPR_P (new_decl);
1244 if (DECL_IMMEDIATE_FUNCTION_P (new_decl))
1245 SET_DECL_IMMEDIATE_FUNCTION_P (old_decl);
1246 return true;
1247 }
1248 /* 7.1.5 [dcl.constexpr]
1249 Note: An explicit specialization can differ from the template
1250 declaration with respect to the constexpr specifier. */
1251 if (! DECL_TEMPLATE_SPECIALIZATION (old_decl)
1252 && DECL_TEMPLATE_SPECIALIZATION (new_decl))
1253 return true;
1254
1255 const char *kind = "constexpr";
1256 if (DECL_IMMEDIATE_FUNCTION_P (old_decl)
1257 || DECL_IMMEDIATE_FUNCTION_P (new_decl))
1258 kind = "consteval";
1259 error_at (DECL_SOURCE_LOCATION (new_decl),
1260 "redeclaration %qD differs in %qs "
1261 "from previous declaration", new_decl,
1262 kind);
1263 inform (DECL_SOURCE_LOCATION (old_decl),
1264 "previous declaration %qD", old_decl);
1265 return false;
1266 }
1267 return true;
1268 }
1269
1270 // If OLDDECL and NEWDECL are concept declarations with the same type
1271 // (i.e., and template parameters), but different requirements,
1272 // emit diagnostics and return true. Otherwise, return false.
1273 static inline bool
check_concept_refinement(tree olddecl,tree newdecl)1274 check_concept_refinement (tree olddecl, tree newdecl)
1275 {
1276 if (!DECL_DECLARED_CONCEPT_P (olddecl) || !DECL_DECLARED_CONCEPT_P (newdecl))
1277 return false;
1278
1279 tree d1 = DECL_TEMPLATE_RESULT (olddecl);
1280 tree d2 = DECL_TEMPLATE_RESULT (newdecl);
1281 if (TREE_CODE (d1) != TREE_CODE (d2))
1282 return false;
1283
1284 tree t1 = TREE_TYPE (d1);
1285 tree t2 = TREE_TYPE (d2);
1286 if (TREE_CODE (d1) == FUNCTION_DECL)
1287 {
1288 if (compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2))
1289 && comp_template_parms (DECL_TEMPLATE_PARMS (olddecl),
1290 DECL_TEMPLATE_PARMS (newdecl))
1291 && !equivalently_constrained (olddecl, newdecl))
1292 {
1293 error ("cannot specialize concept %q#D", olddecl);
1294 return true;
1295 }
1296 }
1297 return false;
1298 }
1299
1300 /* DECL is a redeclaration of a function or function template. If
1301 it does have default arguments issue a diagnostic. Note: this
1302 function is used to enforce the requirements in C++11 8.3.6 about
1303 no default arguments in redeclarations. */
1304
1305 static void
check_redeclaration_no_default_args(tree decl)1306 check_redeclaration_no_default_args (tree decl)
1307 {
1308 gcc_assert (DECL_DECLARES_FUNCTION_P (decl));
1309
1310 for (tree t = FUNCTION_FIRST_USER_PARMTYPE (decl);
1311 t && t != void_list_node; t = TREE_CHAIN (t))
1312 if (TREE_PURPOSE (t))
1313 {
1314 permerror (DECL_SOURCE_LOCATION (decl),
1315 "redeclaration of %q#D may not have default "
1316 "arguments", decl);
1317 return;
1318 }
1319 }
1320
1321 /* NEWDECL is a redeclaration of a function or function template OLDDECL,
1322 in any case represented as FUNCTION_DECLs (the DECL_TEMPLATE_RESULTs of
1323 the TEMPLATE_DECLs in case of function templates). This function is used
1324 to enforce the final part of C++17 11.3.6/4, about a single declaration:
1325 "If a friend declaration specifies a default argument expression, that
1326 declaration shall be a definition and shall be the only declaration of
1327 the function or function template in the translation unit." */
1328
1329 static void
check_no_redeclaration_friend_default_args(tree olddecl,tree newdecl,bool olddecl_hidden_friend_p)1330 check_no_redeclaration_friend_default_args (tree olddecl, tree newdecl,
1331 bool olddecl_hidden_friend_p)
1332 {
1333 if (!olddecl_hidden_friend_p && !DECL_FRIEND_P (newdecl))
1334 return;
1335
1336 tree t1 = FUNCTION_FIRST_USER_PARMTYPE (olddecl);
1337 tree t2 = FUNCTION_FIRST_USER_PARMTYPE (newdecl);
1338
1339 for (; t1 && t1 != void_list_node;
1340 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1341 if ((olddecl_hidden_friend_p && TREE_PURPOSE (t1))
1342 || (DECL_FRIEND_P (newdecl) && TREE_PURPOSE (t2)))
1343 {
1344 auto_diagnostic_group d;
1345 if (permerror (DECL_SOURCE_LOCATION (newdecl),
1346 "friend declaration of %q#D specifies default "
1347 "arguments and isn%'t the only declaration", newdecl))
1348 inform (DECL_SOURCE_LOCATION (olddecl),
1349 "previous declaration of %q#D", olddecl);
1350 return;
1351 }
1352 }
1353
1354 /* Merge tree bits that correspond to attributes noreturn, nothrow,
1355 const, malloc, and pure from NEWDECL with those of OLDDECL. */
1356
1357 static void
merge_attribute_bits(tree newdecl,tree olddecl)1358 merge_attribute_bits (tree newdecl, tree olddecl)
1359 {
1360 TREE_THIS_VOLATILE (newdecl) |= TREE_THIS_VOLATILE (olddecl);
1361 TREE_THIS_VOLATILE (olddecl) |= TREE_THIS_VOLATILE (newdecl);
1362 TREE_NOTHROW (newdecl) |= TREE_NOTHROW (olddecl);
1363 TREE_NOTHROW (olddecl) |= TREE_NOTHROW (newdecl);
1364 TREE_READONLY (newdecl) |= TREE_READONLY (olddecl);
1365 TREE_READONLY (olddecl) |= TREE_READONLY (newdecl);
1366 DECL_IS_MALLOC (newdecl) |= DECL_IS_MALLOC (olddecl);
1367 DECL_IS_MALLOC (olddecl) |= DECL_IS_MALLOC (newdecl);
1368 DECL_PURE_P (newdecl) |= DECL_PURE_P (olddecl);
1369 DECL_PURE_P (olddecl) |= DECL_PURE_P (newdecl);
1370 DECL_UNINLINABLE (newdecl) |= DECL_UNINLINABLE (olddecl);
1371 DECL_UNINLINABLE (olddecl) |= DECL_UNINLINABLE (newdecl);
1372 }
1373
1374 #define GNU_INLINE_P(fn) (DECL_DECLARED_INLINE_P (fn) \
1375 && lookup_attribute ("gnu_inline", \
1376 DECL_ATTRIBUTES (fn)))
1377
1378 /* A subroutine of duplicate_decls. Emits a diagnostic when newdecl
1379 ambiguates olddecl. Returns true if an error occurs. */
1380
1381 static bool
duplicate_function_template_decls(tree newdecl,tree olddecl)1382 duplicate_function_template_decls (tree newdecl, tree olddecl)
1383 {
1384
1385 tree newres = DECL_TEMPLATE_RESULT (newdecl);
1386 tree oldres = DECL_TEMPLATE_RESULT (olddecl);
1387 /* Function template declarations can be differentiated by parameter
1388 and return type. */
1389 if (compparms (TYPE_ARG_TYPES (TREE_TYPE (oldres)),
1390 TYPE_ARG_TYPES (TREE_TYPE (newres)))
1391 && same_type_p (TREE_TYPE (TREE_TYPE (newdecl)),
1392 TREE_TYPE (TREE_TYPE (olddecl))))
1393 {
1394 /* ... and also by their template-heads and requires-clauses. */
1395 if (template_heads_equivalent_p (newdecl, olddecl)
1396 && function_requirements_equivalent_p (newres, oldres))
1397 {
1398 error ("ambiguating new declaration %q+#D", newdecl);
1399 inform (DECL_SOURCE_LOCATION (olddecl),
1400 "old declaration %q#D", olddecl);
1401 return true;
1402 }
1403
1404 /* FIXME: The types are the same but the are differences
1405 in either the template heads or function requirements.
1406 We should be able to diagnose a set of common errors
1407 stemming from these declarations. For example:
1408
1409 template<typename T> requires C void f(...);
1410 template<typename T> void f(...) requires C;
1411
1412 These are functionally equivalent but not equivalent. */
1413 }
1414
1415 return false;
1416 }
1417
1418 /* If NEWDECL is a redeclaration of OLDDECL, merge the declarations.
1419 If the redeclaration is invalid, a diagnostic is issued, and the
1420 error_mark_node is returned. Otherwise, OLDDECL is returned.
1421
1422 If NEWDECL is not a redeclaration of OLDDECL, NULL_TREE is
1423 returned.
1424
1425 NEWDECL_IS_FRIEND is true if NEWDECL was declared as a friend. */
1426
1427 tree
duplicate_decls(tree newdecl,tree olddecl,bool newdecl_is_friend)1428 duplicate_decls (tree newdecl, tree olddecl, bool newdecl_is_friend)
1429 {
1430 unsigned olddecl_uid = DECL_UID (olddecl);
1431 int olddecl_friend = 0, types_match = 0, hidden_friend = 0;
1432 int olddecl_hidden_friend = 0;
1433 int new_defines_function = 0;
1434 tree new_template_info;
1435 location_t olddecl_loc = DECL_SOURCE_LOCATION (olddecl);
1436 location_t newdecl_loc = DECL_SOURCE_LOCATION (newdecl);
1437
1438 if (newdecl == olddecl)
1439 return olddecl;
1440
1441 types_match = decls_match (newdecl, olddecl);
1442
1443 /* If either the type of the new decl or the type of the old decl is an
1444 error_mark_node, then that implies that we have already issued an
1445 error (earlier) for some bogus type specification, and in that case,
1446 it is rather pointless to harass the user with yet more error message
1447 about the same declaration, so just pretend the types match here. */
1448 if (TREE_TYPE (newdecl) == error_mark_node
1449 || TREE_TYPE (olddecl) == error_mark_node)
1450 return error_mark_node;
1451
1452 /* Check for redeclaration and other discrepancies. */
1453 if (TREE_CODE (olddecl) == FUNCTION_DECL
1454 && DECL_ARTIFICIAL (olddecl)
1455 /* A C++20 implicit friend operator== uses the normal path (94462). */
1456 && !DECL_HIDDEN_FRIEND_P (olddecl))
1457 {
1458 if (TREE_CODE (newdecl) != FUNCTION_DECL)
1459 {
1460 /* Avoid warnings redeclaring built-ins which have not been
1461 explicitly declared. */
1462 if (DECL_ANTICIPATED (olddecl))
1463 {
1464 if (TREE_PUBLIC (newdecl)
1465 && CP_DECL_CONTEXT (newdecl) == global_namespace)
1466 warning_at (newdecl_loc,
1467 OPT_Wbuiltin_declaration_mismatch,
1468 "built-in function %qD declared as non-function",
1469 newdecl);
1470 return NULL_TREE;
1471 }
1472
1473 /* If you declare a built-in or predefined function name as static,
1474 the old definition is overridden, but optionally warn this was a
1475 bad choice of name. */
1476 if (! TREE_PUBLIC (newdecl))
1477 {
1478 warning_at (newdecl_loc,
1479 OPT_Wshadow,
1480 fndecl_built_in_p (olddecl)
1481 ? G_("shadowing built-in function %q#D")
1482 : G_("shadowing library function %q#D"), olddecl);
1483 /* Discard the old built-in function. */
1484 return NULL_TREE;
1485 }
1486 /* If the built-in is not ansi, then programs can override
1487 it even globally without an error. */
1488 else if (! fndecl_built_in_p (olddecl))
1489 warning_at (newdecl_loc, 0,
1490 "library function %q#D redeclared as non-function %q#D",
1491 olddecl, newdecl);
1492 else
1493 error_at (newdecl_loc,
1494 "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 (newdecl_loc,
1502 "redeclaration of %<pragma omp declare reduction%>");
1503 inform (olddecl_loc,
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 (newdecl_loc,
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 (fndecl_built_in_p (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 (newdecl_loc,
1592 "definition of %q#D ambiguates built-in "
1593 "declaration %q#D", newdecl, olddecl);
1594 return error_mark_node;
1595 }
1596 auto_diagnostic_group d;
1597 if (permerror (newdecl_loc,
1598 "new declaration %q#D ambiguates built-in"
1599 " declaration %q#D", newdecl, olddecl)
1600 && flag_permissive)
1601 inform (newdecl_loc,
1602 "ignoring the %q#D declaration", newdecl);
1603 return flag_permissive ? olddecl : error_mark_node;
1604 }
1605 }
1606
1607 /* A near match; override the builtin. */
1608
1609 if (TREE_PUBLIC (newdecl))
1610 warning_at (newdecl_loc,
1611 OPT_Wbuiltin_declaration_mismatch,
1612 "new declaration %q#D ambiguates built-in "
1613 "declaration %q#D", newdecl, olddecl);
1614 else
1615 warning (OPT_Wshadow,
1616 fndecl_built_in_p (olddecl)
1617 ? G_("shadowing built-in function %q#D")
1618 : G_("shadowing library function %q#D"), olddecl);
1619 }
1620 else
1621 /* Discard the old built-in function. */
1622 return NULL_TREE;
1623
1624 /* Replace the old RTL to avoid problems with inlining. */
1625 COPY_DECL_RTL (newdecl, olddecl);
1626 }
1627 /* Even if the types match, prefer the new declarations type for
1628 built-ins which have not been explicitly declared, for
1629 exception lists, etc... */
1630 else if (DECL_IS_BUILTIN (olddecl))
1631 {
1632 tree type = TREE_TYPE (newdecl);
1633 tree attribs = (*targetm.merge_type_attributes)
1634 (TREE_TYPE (olddecl), type);
1635
1636 type = cp_build_type_attribute_variant (type, attribs);
1637 TREE_TYPE (newdecl) = TREE_TYPE (olddecl) = type;
1638 }
1639
1640 /* If a function is explicitly declared "throw ()", propagate that to
1641 the corresponding builtin. */
1642 if (DECL_BUILT_IN_CLASS (olddecl) == BUILT_IN_NORMAL
1643 && DECL_ANTICIPATED (olddecl)
1644 && TREE_NOTHROW (newdecl)
1645 && !TREE_NOTHROW (olddecl))
1646 {
1647 enum built_in_function fncode = DECL_FUNCTION_CODE (olddecl);
1648 tree tmpdecl = builtin_decl_explicit (fncode);
1649 if (tmpdecl && tmpdecl != olddecl && types_match)
1650 TREE_NOTHROW (tmpdecl) = 1;
1651 }
1652
1653 /* Whether or not the builtin can throw exceptions has no
1654 bearing on this declarator. */
1655 TREE_NOTHROW (olddecl) = 0;
1656
1657 if (DECL_THIS_STATIC (newdecl) && !DECL_THIS_STATIC (olddecl))
1658 {
1659 /* If a builtin function is redeclared as `static', merge
1660 the declarations, but make the original one static. */
1661 DECL_THIS_STATIC (olddecl) = 1;
1662 TREE_PUBLIC (olddecl) = 0;
1663
1664 /* Make the old declaration consistent with the new one so
1665 that all remnants of the builtin-ness of this function
1666 will be banished. */
1667 SET_DECL_LANGUAGE (olddecl, DECL_LANGUAGE (newdecl));
1668 COPY_DECL_RTL (newdecl, olddecl);
1669 }
1670 }
1671 else if (TREE_CODE (olddecl) != TREE_CODE (newdecl))
1672 {
1673 /* C++ Standard, 3.3, clause 4:
1674 "[Note: a namespace name or a class template name must be unique
1675 in its declarative region (7.3.2, clause 14). ]" */
1676 if (TREE_CODE (olddecl) == NAMESPACE_DECL
1677 || TREE_CODE (newdecl) == NAMESPACE_DECL)
1678 /* Namespace conflicts with not namespace. */;
1679 else if (DECL_TYPE_TEMPLATE_P (olddecl)
1680 || DECL_TYPE_TEMPLATE_P (newdecl))
1681 /* Class template conflicts. */;
1682 else if ((TREE_CODE (newdecl) == FUNCTION_DECL
1683 && DECL_FUNCTION_TEMPLATE_P (olddecl))
1684 || (TREE_CODE (olddecl) == FUNCTION_DECL
1685 && DECL_FUNCTION_TEMPLATE_P (newdecl)))
1686 {
1687 /* One is a function and the other is a template
1688 function. */
1689 if (!UDLIT_OPER_P (DECL_NAME (newdecl)))
1690 return NULL_TREE;
1691
1692 /* There can only be one! */
1693 if (TREE_CODE (newdecl) == TEMPLATE_DECL
1694 && check_raw_literal_operator (olddecl))
1695 error_at (newdecl_loc,
1696 "literal operator %q#D conflicts with"
1697 " raw literal operator", newdecl);
1698 else if (check_raw_literal_operator (newdecl))
1699 error_at (newdecl_loc,
1700 "raw literal operator %q#D conflicts with"
1701 " literal operator template", newdecl);
1702 else
1703 return NULL_TREE;
1704
1705 inform (olddecl_loc, "previous declaration %q#D", olddecl);
1706 return error_mark_node;
1707 }
1708 else if (DECL_IMPLICIT_TYPEDEF_P (olddecl)
1709 || DECL_IMPLICIT_TYPEDEF_P (newdecl))
1710 /* One is an implicit typedef, that's ok. */
1711 return NULL_TREE;
1712
1713 error ("%q#D redeclared as different kind of entity", newdecl);
1714 inform (olddecl_loc, "previous declaration %q#D", olddecl);
1715
1716 return error_mark_node;
1717 }
1718 else if (!types_match)
1719 {
1720 if (CP_DECL_CONTEXT (newdecl) != CP_DECL_CONTEXT (olddecl))
1721 /* These are certainly not duplicate declarations; they're
1722 from different scopes. */
1723 return NULL_TREE;
1724
1725 if (TREE_CODE (newdecl) == TEMPLATE_DECL)
1726 {
1727 tree oldres = DECL_TEMPLATE_RESULT (olddecl);
1728 tree newres = DECL_TEMPLATE_RESULT (newdecl);
1729
1730 /* The name of a class template may not be declared to refer to
1731 any other template, class, function, object, namespace, value,
1732 or type in the same scope. */
1733 if (TREE_CODE (oldres) == TYPE_DECL
1734 || TREE_CODE (newres) == TYPE_DECL)
1735 {
1736 error_at (newdecl_loc,
1737 "conflicting declaration of template %q#D", newdecl);
1738 inform (olddecl_loc,
1739 "previous declaration %q#D", olddecl);
1740 return error_mark_node;
1741 }
1742
1743 else if (TREE_CODE (oldres) == FUNCTION_DECL
1744 && TREE_CODE (newres) == FUNCTION_DECL)
1745 {
1746 if (duplicate_function_template_decls (newdecl, olddecl))
1747 return error_mark_node;
1748 return NULL_TREE;
1749 }
1750 else if (check_concept_refinement (olddecl, newdecl))
1751 return error_mark_node;
1752 return NULL_TREE;
1753 }
1754 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1755 {
1756 if (DECL_EXTERN_C_P (newdecl) && DECL_EXTERN_C_P (olddecl))
1757 {
1758 error_at (newdecl_loc,
1759 "conflicting declaration of C function %q#D",
1760 newdecl);
1761 inform (olddecl_loc,
1762 "previous declaration %q#D", olddecl);
1763 return NULL_TREE;
1764 }
1765 /* For function versions, params and types match, but they
1766 are not ambiguous. */
1767 else if ((!DECL_FUNCTION_VERSIONED (newdecl)
1768 && !DECL_FUNCTION_VERSIONED (olddecl))
1769 // The functions have the same parameter types.
1770 && compparms (TYPE_ARG_TYPES (TREE_TYPE (newdecl)),
1771 TYPE_ARG_TYPES (TREE_TYPE (olddecl)))
1772 // And the same constraints.
1773 && equivalently_constrained (newdecl, olddecl))
1774 {
1775 error_at (newdecl_loc,
1776 "ambiguating new declaration of %q#D", newdecl);
1777 inform (olddecl_loc,
1778 "old declaration %q#D", olddecl);
1779 return error_mark_node;
1780 }
1781 else
1782 return NULL_TREE;
1783 }
1784 else
1785 {
1786 error_at (newdecl_loc, "conflicting declaration %q#D", newdecl);
1787 inform (olddecl_loc,
1788 "previous declaration as %q#D", olddecl);
1789 return error_mark_node;
1790 }
1791 }
1792 else if (TREE_CODE (newdecl) == FUNCTION_DECL
1793 && ((DECL_TEMPLATE_SPECIALIZATION (olddecl)
1794 && (!DECL_TEMPLATE_INFO (newdecl)
1795 || (DECL_TI_TEMPLATE (newdecl)
1796 != DECL_TI_TEMPLATE (olddecl))))
1797 || (DECL_TEMPLATE_SPECIALIZATION (newdecl)
1798 && (!DECL_TEMPLATE_INFO (olddecl)
1799 || (DECL_TI_TEMPLATE (olddecl)
1800 != DECL_TI_TEMPLATE (newdecl))))))
1801 /* It's OK to have a template specialization and a non-template
1802 with the same type, or to have specializations of two
1803 different templates with the same type. Note that if one is a
1804 specialization, and the other is an instantiation of the same
1805 template, that we do not exit at this point. That situation
1806 can occur if we instantiate a template class, and then
1807 specialize one of its methods. This situation is valid, but
1808 the declarations must be merged in the usual way. */
1809 return NULL_TREE;
1810 else if (TREE_CODE (newdecl) == FUNCTION_DECL
1811 && ((DECL_TEMPLATE_INSTANTIATION (olddecl)
1812 && !DECL_USE_TEMPLATE (newdecl))
1813 || (DECL_TEMPLATE_INSTANTIATION (newdecl)
1814 && !DECL_USE_TEMPLATE (olddecl))))
1815 /* One of the declarations is a template instantiation, and the
1816 other is not a template at all. That's OK. */
1817 return NULL_TREE;
1818 else if (TREE_CODE (newdecl) == NAMESPACE_DECL)
1819 {
1820 /* In [namespace.alias] we have:
1821
1822 In a declarative region, a namespace-alias-definition can be
1823 used to redefine a namespace-alias declared in that declarative
1824 region to refer only to the namespace to which it already
1825 refers.
1826
1827 Therefore, if we encounter a second alias directive for the same
1828 alias, we can just ignore the second directive. */
1829 if (DECL_NAMESPACE_ALIAS (newdecl)
1830 && (DECL_NAMESPACE_ALIAS (newdecl)
1831 == DECL_NAMESPACE_ALIAS (olddecl)))
1832 return olddecl;
1833
1834 /* Leave it to update_binding to merge or report error. */
1835 return NULL_TREE;
1836 }
1837 else
1838 {
1839 const char *errmsg = redeclaration_error_message (newdecl, olddecl);
1840 if (errmsg)
1841 {
1842 auto_diagnostic_group d;
1843 error_at (newdecl_loc, errmsg, newdecl);
1844 if (DECL_NAME (olddecl) != NULL_TREE)
1845 inform (olddecl_loc,
1846 (DECL_INITIAL (olddecl) && namespace_bindings_p ())
1847 ? G_("%q#D previously defined here")
1848 : G_("%q#D previously declared here"), olddecl);
1849 return error_mark_node;
1850 }
1851 else if (TREE_CODE (olddecl) == FUNCTION_DECL
1852 && DECL_INITIAL (olddecl) != NULL_TREE
1853 && !prototype_p (TREE_TYPE (olddecl))
1854 && prototype_p (TREE_TYPE (newdecl)))
1855 {
1856 /* Prototype decl follows defn w/o prototype. */
1857 auto_diagnostic_group d;
1858 if (warning_at (newdecl_loc, 0,
1859 "prototype specified for %q#D", newdecl))
1860 inform (olddecl_loc,
1861 "previous non-prototype definition here");
1862 }
1863 else if (VAR_OR_FUNCTION_DECL_P (olddecl)
1864 && DECL_LANGUAGE (newdecl) != DECL_LANGUAGE (olddecl))
1865 {
1866 /* [dcl.link]
1867 If two declarations of the same function or object
1868 specify different linkage-specifications ..., the program
1869 is ill-formed.... Except for functions with C++ linkage,
1870 a function declaration without a linkage specification
1871 shall not precede the first linkage specification for
1872 that function. A function can be declared without a
1873 linkage specification after an explicit linkage
1874 specification has been seen; the linkage explicitly
1875 specified in the earlier declaration is not affected by
1876 such a function declaration.
1877
1878 DR 563 raises the question why the restrictions on
1879 functions should not also apply to objects. Older
1880 versions of G++ silently ignore the linkage-specification
1881 for this example:
1882
1883 namespace N {
1884 extern int i;
1885 extern "C" int i;
1886 }
1887
1888 which is clearly wrong. Therefore, we now treat objects
1889 like functions. */
1890 if (current_lang_depth () == 0)
1891 {
1892 /* There is no explicit linkage-specification, so we use
1893 the linkage from the previous declaration. */
1894 retrofit_lang_decl (newdecl);
1895 SET_DECL_LANGUAGE (newdecl, DECL_LANGUAGE (olddecl));
1896 }
1897 else
1898 {
1899 auto_diagnostic_group d;
1900 error_at (newdecl_loc,
1901 "conflicting declaration of %q#D with %qL linkage",
1902 newdecl, DECL_LANGUAGE (newdecl));
1903 inform (olddecl_loc,
1904 "previous declaration with %qL linkage",
1905 DECL_LANGUAGE (olddecl));
1906 }
1907 }
1908
1909 if (DECL_LANG_SPECIFIC (olddecl) && DECL_USE_TEMPLATE (olddecl))
1910 ;
1911 else if (TREE_CODE (olddecl) == FUNCTION_DECL)
1912 {
1913 /* Note: free functions, as TEMPLATE_DECLs, are handled below. */
1914 if (DECL_FUNCTION_MEMBER_P (olddecl)
1915 && (/* grokfndecl passes member function templates too
1916 as FUNCTION_DECLs. */
1917 DECL_TEMPLATE_INFO (olddecl)
1918 /* C++11 8.3.6/6.
1919 Default arguments for a member function of a class
1920 template shall be specified on the initial declaration
1921 of the member function within the class template. */
1922 || CLASSTYPE_TEMPLATE_INFO (CP_DECL_CONTEXT (olddecl))))
1923 check_redeclaration_no_default_args (newdecl);
1924 else
1925 {
1926 tree t1 = FUNCTION_FIRST_USER_PARMTYPE (olddecl);
1927 tree t2 = FUNCTION_FIRST_USER_PARMTYPE (newdecl);
1928 int i = 1;
1929
1930 for (; t1 && t1 != void_list_node;
1931 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2), i++)
1932 if (TREE_PURPOSE (t1) && TREE_PURPOSE (t2))
1933 {
1934 if (simple_cst_equal (TREE_PURPOSE (t1),
1935 TREE_PURPOSE (t2)) == 1)
1936 {
1937 auto_diagnostic_group d;
1938 if (permerror (newdecl_loc,
1939 "default argument given for parameter "
1940 "%d of %q#D", i, newdecl))
1941 inform (olddecl_loc,
1942 "previous specification in %q#D here",
1943 olddecl);
1944 }
1945 else
1946 {
1947 auto_diagnostic_group d;
1948 error_at (newdecl_loc,
1949 "default argument given for parameter %d "
1950 "of %q#D", i, newdecl);
1951 inform (olddecl_loc,
1952 "previous specification in %q#D here",
1953 olddecl);
1954 }
1955 }
1956
1957 /* C++17 11.3.6/4: "If a friend declaration specifies a default
1958 argument expression, that declaration... shall be the only
1959 declaration of the function or function template in the
1960 translation unit." */
1961 check_no_redeclaration_friend_default_args
1962 (olddecl, newdecl, DECL_HIDDEN_FRIEND_P (olddecl));
1963 }
1964 }
1965 }
1966
1967 /* Do not merge an implicit typedef with an explicit one. In:
1968
1969 class A;
1970 ...
1971 typedef class A A __attribute__ ((foo));
1972
1973 the attribute should apply only to the typedef. */
1974 if (TREE_CODE (olddecl) == TYPE_DECL
1975 && (DECL_IMPLICIT_TYPEDEF_P (olddecl)
1976 || DECL_IMPLICIT_TYPEDEF_P (newdecl)))
1977 return NULL_TREE;
1978
1979 if (!validate_constexpr_redeclaration (olddecl, newdecl))
1980 return error_mark_node;
1981
1982 /* We have committed to returning OLDDECL at this point. */
1983
1984 /* If new decl is `static' and an `extern' was seen previously,
1985 warn about it. */
1986 warn_extern_redeclared_static (newdecl, olddecl);
1987
1988 /* True to merge attributes between the declarations, false to
1989 set OLDDECL's attributes to those of NEWDECL (for template
1990 explicit specializations that specify their own attributes
1991 independent of those specified for the primary template). */
1992 const bool merge_attr = (TREE_CODE (newdecl) != FUNCTION_DECL
1993 || !DECL_TEMPLATE_SPECIALIZATION (newdecl)
1994 || DECL_TEMPLATE_SPECIALIZATION (olddecl));
1995
1996 if (TREE_CODE (newdecl) == FUNCTION_DECL)
1997 {
1998 if (merge_attr)
1999 {
2000 if (diagnose_mismatched_attributes (olddecl, newdecl))
2001 inform (olddecl_loc, DECL_INITIAL (olddecl)
2002 ? G_("previous definition of %qD here")
2003 : G_("previous declaration of %qD here"), olddecl);
2004
2005 /* [dcl.attr.noreturn]: The first declaration of a function shall
2006 specify the noreturn attribute if any declaration of that function
2007 specifies the noreturn attribute. */
2008 tree a;
2009 if (TREE_THIS_VOLATILE (newdecl)
2010 && !TREE_THIS_VOLATILE (olddecl)
2011 /* This applies to [[noreturn]] only, not its GNU variants. */
2012 && (a = lookup_attribute ("noreturn", DECL_ATTRIBUTES (newdecl)))
2013 && cxx11_attribute_p (a)
2014 && get_attribute_namespace (a) == NULL_TREE)
2015 {
2016 error_at (newdecl_loc, "function %qD declared %<[[noreturn]]%> "
2017 "but its first declaration was not", newdecl);
2018 inform (olddecl_loc, "previous declaration of %qD", olddecl);
2019 }
2020 }
2021
2022 /* Now that functions must hold information normally held
2023 by field decls, there is extra work to do so that
2024 declaration information does not get destroyed during
2025 definition. */
2026 if (DECL_VINDEX (olddecl))
2027 DECL_VINDEX (newdecl) = DECL_VINDEX (olddecl);
2028 if (DECL_CONTEXT (olddecl))
2029 DECL_CONTEXT (newdecl) = DECL_CONTEXT (olddecl);
2030 DECL_STATIC_CONSTRUCTOR (newdecl) |= DECL_STATIC_CONSTRUCTOR (olddecl);
2031 DECL_STATIC_DESTRUCTOR (newdecl) |= DECL_STATIC_DESTRUCTOR (olddecl);
2032 DECL_PURE_VIRTUAL_P (newdecl) |= DECL_PURE_VIRTUAL_P (olddecl);
2033 DECL_VIRTUAL_P (newdecl) |= DECL_VIRTUAL_P (olddecl);
2034 DECL_INVALID_OVERRIDER_P (newdecl) |= DECL_INVALID_OVERRIDER_P (olddecl);
2035 DECL_FINAL_P (newdecl) |= DECL_FINAL_P (olddecl);
2036 DECL_OVERRIDE_P (newdecl) |= DECL_OVERRIDE_P (olddecl);
2037 DECL_THIS_STATIC (newdecl) |= DECL_THIS_STATIC (olddecl);
2038 DECL_HAS_DEPENDENT_EXPLICIT_SPEC_P (newdecl)
2039 |= DECL_HAS_DEPENDENT_EXPLICIT_SPEC_P (olddecl);
2040 if (DECL_OVERLOADED_OPERATOR_P (olddecl))
2041 DECL_OVERLOADED_OPERATOR_CODE_RAW (newdecl)
2042 = DECL_OVERLOADED_OPERATOR_CODE_RAW (olddecl);
2043 new_defines_function = DECL_INITIAL (newdecl) != NULL_TREE;
2044
2045 /* Optionally warn about more than one declaration for the same
2046 name, but don't warn about a function declaration followed by a
2047 definition. */
2048 if (warn_redundant_decls && ! DECL_ARTIFICIAL (olddecl)
2049 && !(new_defines_function && DECL_INITIAL (olddecl) == NULL_TREE)
2050 /* Don't warn about extern decl followed by definition. */
2051 && !(DECL_EXTERNAL (olddecl) && ! DECL_EXTERNAL (newdecl))
2052 /* Don't warn about friends, let add_friend take care of it. */
2053 && ! (newdecl_is_friend || DECL_FRIEND_P (olddecl))
2054 /* Don't warn about declaration followed by specialization. */
2055 && (! DECL_TEMPLATE_SPECIALIZATION (newdecl)
2056 || DECL_TEMPLATE_SPECIALIZATION (olddecl)))
2057 {
2058 auto_diagnostic_group d;
2059 if (warning_at (newdecl_loc,
2060 OPT_Wredundant_decls,
2061 "redundant redeclaration of %qD in same scope",
2062 newdecl))
2063 inform (olddecl_loc,
2064 "previous declaration of %qD", olddecl);
2065 }
2066
2067 if (!(DECL_TEMPLATE_INSTANTIATION (olddecl)
2068 && DECL_TEMPLATE_SPECIALIZATION (newdecl)))
2069 {
2070 if (DECL_DELETED_FN (newdecl))
2071 {
2072 auto_diagnostic_group d;
2073 error_at (newdecl_loc, "deleted definition of %qD", newdecl);
2074 inform (olddecl_loc,
2075 "previous declaration of %qD", olddecl);
2076 }
2077 DECL_DELETED_FN (newdecl) |= DECL_DELETED_FN (olddecl);
2078 }
2079 }
2080
2081 /* Deal with C++: must preserve virtual function table size. */
2082 if (TREE_CODE (olddecl) == TYPE_DECL)
2083 {
2084 tree newtype = TREE_TYPE (newdecl);
2085 tree oldtype = TREE_TYPE (olddecl);
2086
2087 if (newtype != error_mark_node && oldtype != error_mark_node
2088 && TYPE_LANG_SPECIFIC (newtype) && TYPE_LANG_SPECIFIC (oldtype))
2089 CLASSTYPE_FRIEND_CLASSES (newtype)
2090 = CLASSTYPE_FRIEND_CLASSES (oldtype);
2091
2092 DECL_ORIGINAL_TYPE (newdecl) = DECL_ORIGINAL_TYPE (olddecl);
2093 }
2094
2095 /* Copy all the DECL_... slots specified in the new decl except for
2096 any that we copy here from the old type. */
2097 if (merge_attr)
2098 DECL_ATTRIBUTES (newdecl)
2099 = (*targetm.merge_decl_attributes) (olddecl, newdecl);
2100 else
2101 DECL_ATTRIBUTES (olddecl) = DECL_ATTRIBUTES (newdecl);
2102
2103 if (DECL_DECLARES_FUNCTION_P (olddecl))
2104 {
2105 olddecl_friend = DECL_FRIEND_P (olddecl);
2106 olddecl_hidden_friend = DECL_HIDDEN_FRIEND_P (olddecl);
2107 hidden_friend = (DECL_ANTICIPATED (olddecl)
2108 && DECL_HIDDEN_FRIEND_P (olddecl)
2109 && newdecl_is_friend);
2110 if (!hidden_friend)
2111 {
2112 DECL_ANTICIPATED (olddecl) = 0;
2113 DECL_HIDDEN_FRIEND_P (olddecl) = 0;
2114 }
2115 }
2116
2117 if (TREE_CODE (newdecl) == TEMPLATE_DECL)
2118 {
2119 tree old_result = DECL_TEMPLATE_RESULT (olddecl);
2120 tree new_result = DECL_TEMPLATE_RESULT (newdecl);
2121 TREE_TYPE (olddecl) = TREE_TYPE (old_result);
2122
2123 /* The new decl should not already have gathered any
2124 specializations. */
2125 gcc_assert (!DECL_TEMPLATE_SPECIALIZATIONS (newdecl));
2126
2127 DECL_ATTRIBUTES (old_result)
2128 = (*targetm.merge_decl_attributes) (old_result, new_result);
2129
2130 if (DECL_FUNCTION_TEMPLATE_P (newdecl))
2131 {
2132 if (DECL_SOURCE_LOCATION (newdecl)
2133 != DECL_SOURCE_LOCATION (olddecl))
2134 {
2135 /* Per C++11 8.3.6/4, default arguments cannot be added in
2136 later declarations of a function template. */
2137 check_redeclaration_no_default_args (newdecl);
2138 /* C++17 11.3.6/4: "If a friend declaration specifies a default
2139 argument expression, that declaration... shall be the only
2140 declaration of the function or function template in the
2141 translation unit." */
2142 check_no_redeclaration_friend_default_args
2143 (old_result, new_result, olddecl_hidden_friend);
2144 }
2145
2146 check_default_args (newdecl);
2147
2148 if (GNU_INLINE_P (old_result) != GNU_INLINE_P (new_result)
2149 && DECL_INITIAL (new_result))
2150 {
2151 if (DECL_INITIAL (old_result))
2152 DECL_UNINLINABLE (old_result) = 1;
2153 else
2154 DECL_UNINLINABLE (old_result) = DECL_UNINLINABLE (new_result);
2155 DECL_EXTERNAL (old_result) = DECL_EXTERNAL (new_result);
2156 DECL_NOT_REALLY_EXTERN (old_result)
2157 = DECL_NOT_REALLY_EXTERN (new_result);
2158 DECL_INTERFACE_KNOWN (old_result)
2159 = DECL_INTERFACE_KNOWN (new_result);
2160 DECL_DECLARED_INLINE_P (old_result)
2161 = DECL_DECLARED_INLINE_P (new_result);
2162 DECL_DISREGARD_INLINE_LIMITS (old_result)
2163 |= DECL_DISREGARD_INLINE_LIMITS (new_result);
2164
2165 }
2166 else
2167 {
2168 DECL_DECLARED_INLINE_P (old_result)
2169 |= DECL_DECLARED_INLINE_P (new_result);
2170 DECL_DISREGARD_INLINE_LIMITS (old_result)
2171 |= DECL_DISREGARD_INLINE_LIMITS (new_result);
2172 check_redeclaration_exception_specification (newdecl, olddecl);
2173
2174 merge_attribute_bits (new_result, old_result);
2175 }
2176 }
2177
2178 /* If the new declaration is a definition, update the file and
2179 line information on the declaration, and also make
2180 the old declaration the same definition. */
2181 if (DECL_INITIAL (new_result) != NULL_TREE)
2182 {
2183 DECL_SOURCE_LOCATION (olddecl)
2184 = DECL_SOURCE_LOCATION (old_result)
2185 = DECL_SOURCE_LOCATION (newdecl);
2186 DECL_INITIAL (old_result) = DECL_INITIAL (new_result);
2187 if (DECL_FUNCTION_TEMPLATE_P (newdecl))
2188 {
2189 tree parm;
2190 DECL_ARGUMENTS (old_result)
2191 = DECL_ARGUMENTS (new_result);
2192 for (parm = DECL_ARGUMENTS (old_result); parm;
2193 parm = DECL_CHAIN (parm))
2194 DECL_CONTEXT (parm) = old_result;
2195 }
2196 }
2197
2198 return olddecl;
2199 }
2200
2201 if (types_match)
2202 {
2203 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2204 check_redeclaration_exception_specification (newdecl, olddecl);
2205
2206 /* Automatically handles default parameters. */
2207 tree oldtype = TREE_TYPE (olddecl);
2208 tree newtype;
2209
2210 /* For typedefs use the old type, as the new type's DECL_NAME points
2211 at newdecl, which will be ggc_freed. */
2212 if (TREE_CODE (newdecl) == TYPE_DECL)
2213 {
2214 /* But NEWTYPE might have an attribute, honor that. */
2215 tree tem = TREE_TYPE (newdecl);
2216 newtype = oldtype;
2217
2218 if (TYPE_USER_ALIGN (tem))
2219 {
2220 if (TYPE_ALIGN (tem) > TYPE_ALIGN (newtype))
2221 SET_TYPE_ALIGN (newtype, TYPE_ALIGN (tem));
2222 TYPE_USER_ALIGN (newtype) = true;
2223 }
2224
2225 /* And remove the new type from the variants list. */
2226 if (TYPE_NAME (TREE_TYPE (newdecl)) == newdecl)
2227 {
2228 tree remove = TREE_TYPE (newdecl);
2229 if (TYPE_MAIN_VARIANT (remove) == remove)
2230 {
2231 gcc_assert (TYPE_NEXT_VARIANT (remove) == NULL_TREE);
2232 /* If remove is the main variant, no need to remove that
2233 from the list. One of the DECL_ORIGINAL_TYPE
2234 variants, e.g. created for aligned attribute, might still
2235 refer to the newdecl TYPE_DECL though, so remove that one
2236 in that case. */
2237 if (tree orig = DECL_ORIGINAL_TYPE (newdecl))
2238 if (orig != remove)
2239 for (tree t = TYPE_MAIN_VARIANT (orig); t;
2240 t = TYPE_MAIN_VARIANT (t))
2241 if (TYPE_NAME (TYPE_NEXT_VARIANT (t)) == newdecl)
2242 {
2243 TYPE_NEXT_VARIANT (t)
2244 = TYPE_NEXT_VARIANT (TYPE_NEXT_VARIANT (t));
2245 break;
2246 }
2247 }
2248 else
2249 for (tree t = TYPE_MAIN_VARIANT (remove); ;
2250 t = TYPE_NEXT_VARIANT (t))
2251 if (TYPE_NEXT_VARIANT (t) == remove)
2252 {
2253 TYPE_NEXT_VARIANT (t) = TYPE_NEXT_VARIANT (remove);
2254 break;
2255 }
2256 }
2257 }
2258 else if (merge_attr)
2259 newtype = merge_types (TREE_TYPE (newdecl), TREE_TYPE (olddecl));
2260 else
2261 newtype = TREE_TYPE (newdecl);
2262
2263 if (VAR_P (newdecl))
2264 {
2265 DECL_THIS_EXTERN (newdecl) |= DECL_THIS_EXTERN (olddecl);
2266 /* For already initialized vars, TREE_READONLY could have been
2267 cleared in cp_finish_decl, because the var needs runtime
2268 initialization or destruction. Make sure not to set
2269 TREE_READONLY on it again. */
2270 if (DECL_INITIALIZED_P (olddecl)
2271 && !DECL_EXTERNAL (olddecl)
2272 && !TREE_READONLY (olddecl))
2273 TREE_READONLY (newdecl) = 0;
2274 DECL_INITIALIZED_P (newdecl) |= DECL_INITIALIZED_P (olddecl);
2275 DECL_NONTRIVIALLY_INITIALIZED_P (newdecl)
2276 |= DECL_NONTRIVIALLY_INITIALIZED_P (olddecl);
2277 if (DECL_DEPENDENT_INIT_P (olddecl))
2278 SET_DECL_DEPENDENT_INIT_P (newdecl, true);
2279 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (newdecl)
2280 |= DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (olddecl);
2281 DECL_DECLARED_CONSTEXPR_P (newdecl)
2282 |= DECL_DECLARED_CONSTEXPR_P (olddecl);
2283
2284 /* Merge the threadprivate attribute from OLDDECL into NEWDECL. */
2285 if (DECL_LANG_SPECIFIC (olddecl)
2286 && CP_DECL_THREADPRIVATE_P (olddecl))
2287 {
2288 /* Allocate a LANG_SPECIFIC structure for NEWDECL, if needed. */
2289 retrofit_lang_decl (newdecl);
2290 CP_DECL_THREADPRIVATE_P (newdecl) = 1;
2291 }
2292 }
2293
2294 /* An explicit specialization of a function template or of a member
2295 function of a class template can be declared transaction_safe
2296 independently of whether the corresponding template entity is declared
2297 transaction_safe. */
2298 if (flag_tm && TREE_CODE (newdecl) == FUNCTION_DECL
2299 && DECL_TEMPLATE_INSTANTIATION (olddecl)
2300 && DECL_TEMPLATE_SPECIALIZATION (newdecl)
2301 && tx_safe_fn_type_p (newtype)
2302 && !tx_safe_fn_type_p (TREE_TYPE (newdecl)))
2303 newtype = tx_unsafe_fn_variant (newtype);
2304
2305 TREE_TYPE (newdecl) = TREE_TYPE (olddecl) = newtype;
2306
2307 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2308 check_default_args (newdecl);
2309
2310 /* Lay the type out, unless already done. */
2311 if (! same_type_p (newtype, oldtype)
2312 && TREE_TYPE (newdecl) != error_mark_node
2313 && !(processing_template_decl && uses_template_parms (newdecl)))
2314 layout_type (TREE_TYPE (newdecl));
2315
2316 if ((VAR_P (newdecl)
2317 || TREE_CODE (newdecl) == PARM_DECL
2318 || TREE_CODE (newdecl) == RESULT_DECL
2319 || TREE_CODE (newdecl) == FIELD_DECL
2320 || TREE_CODE (newdecl) == TYPE_DECL)
2321 && !(processing_template_decl && uses_template_parms (newdecl)))
2322 layout_decl (newdecl, 0);
2323
2324 /* Merge deprecatedness. */
2325 if (TREE_DEPRECATED (newdecl))
2326 TREE_DEPRECATED (olddecl) = 1;
2327
2328 /* Preserve function specific target and optimization options */
2329 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2330 {
2331 if (DECL_FUNCTION_SPECIFIC_TARGET (olddecl)
2332 && !DECL_FUNCTION_SPECIFIC_TARGET (newdecl))
2333 DECL_FUNCTION_SPECIFIC_TARGET (newdecl)
2334 = DECL_FUNCTION_SPECIFIC_TARGET (olddecl);
2335
2336 if (DECL_FUNCTION_SPECIFIC_OPTIMIZATION (olddecl)
2337 && !DECL_FUNCTION_SPECIFIC_OPTIMIZATION (newdecl))
2338 DECL_FUNCTION_SPECIFIC_OPTIMIZATION (newdecl)
2339 = DECL_FUNCTION_SPECIFIC_OPTIMIZATION (olddecl);
2340 }
2341 else
2342 {
2343 /* Merge the const type qualifier. */
2344 if (TREE_READONLY (newdecl))
2345 TREE_READONLY (olddecl) = 1;
2346 /* Merge the volatile type qualifier. */
2347 if (TREE_THIS_VOLATILE (newdecl))
2348 TREE_THIS_VOLATILE (olddecl) = 1;
2349 }
2350
2351 /* Merge the initialization information. */
2352 if (DECL_INITIAL (newdecl) == NULL_TREE
2353 && DECL_INITIAL (olddecl) != NULL_TREE)
2354 {
2355 DECL_INITIAL (newdecl) = DECL_INITIAL (olddecl);
2356 DECL_SOURCE_LOCATION (newdecl) = DECL_SOURCE_LOCATION (olddecl);
2357 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2358 {
2359 DECL_SAVED_TREE (newdecl) = DECL_SAVED_TREE (olddecl);
2360 DECL_STRUCT_FUNCTION (newdecl) = DECL_STRUCT_FUNCTION (olddecl);
2361 }
2362 }
2363
2364 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2365 {
2366 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (newdecl)
2367 |= DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (olddecl);
2368 DECL_NO_LIMIT_STACK (newdecl) |= DECL_NO_LIMIT_STACK (olddecl);
2369 if (DECL_IS_OPERATOR_NEW_P (olddecl))
2370 DECL_SET_IS_OPERATOR_NEW (newdecl, true);
2371 DECL_LOOPING_CONST_OR_PURE_P (newdecl)
2372 |= DECL_LOOPING_CONST_OR_PURE_P (olddecl);
2373 DECL_IS_REPLACEABLE_OPERATOR (newdecl)
2374 |= DECL_IS_REPLACEABLE_OPERATOR (olddecl);
2375
2376 if (merge_attr)
2377 merge_attribute_bits (newdecl, olddecl);
2378 else
2379 {
2380 /* Merge the noreturn bit. */
2381 TREE_THIS_VOLATILE (olddecl) = TREE_THIS_VOLATILE (newdecl);
2382 TREE_READONLY (olddecl) = TREE_READONLY (newdecl);
2383 TREE_NOTHROW (olddecl) = TREE_NOTHROW (newdecl);
2384 DECL_IS_MALLOC (olddecl) = DECL_IS_MALLOC (newdecl);
2385 DECL_PURE_P (olddecl) = DECL_PURE_P (newdecl);
2386 }
2387 /* Keep the old RTL. */
2388 COPY_DECL_RTL (olddecl, newdecl);
2389 }
2390 else if (VAR_P (newdecl)
2391 && (DECL_SIZE (olddecl) || !DECL_SIZE (newdecl)))
2392 {
2393 /* Keep the old RTL. We cannot keep the old RTL if the old
2394 declaration was for an incomplete object and the new
2395 declaration is not since many attributes of the RTL will
2396 change. */
2397 COPY_DECL_RTL (olddecl, newdecl);
2398 }
2399 }
2400 /* If cannot merge, then use the new type and qualifiers,
2401 and don't preserve the old rtl. */
2402 else
2403 {
2404 /* Clean out any memory we had of the old declaration. */
2405 tree oldstatic = value_member (olddecl, static_aggregates);
2406 if (oldstatic)
2407 TREE_VALUE (oldstatic) = error_mark_node;
2408
2409 TREE_TYPE (olddecl) = TREE_TYPE (newdecl);
2410 TREE_READONLY (olddecl) = TREE_READONLY (newdecl);
2411 TREE_THIS_VOLATILE (olddecl) = TREE_THIS_VOLATILE (newdecl);
2412 TREE_NOTHROW (olddecl) = TREE_NOTHROW (newdecl);
2413 TREE_SIDE_EFFECTS (olddecl) = TREE_SIDE_EFFECTS (newdecl);
2414 }
2415
2416 /* Merge the storage class information. */
2417 merge_weak (newdecl, olddecl);
2418
2419 DECL_DEFER_OUTPUT (newdecl) |= DECL_DEFER_OUTPUT (olddecl);
2420 TREE_PUBLIC (newdecl) = TREE_PUBLIC (olddecl);
2421 TREE_STATIC (olddecl) = TREE_STATIC (newdecl) |= TREE_STATIC (olddecl);
2422 if (! DECL_EXTERNAL (olddecl))
2423 DECL_EXTERNAL (newdecl) = 0;
2424 if (! DECL_COMDAT (olddecl))
2425 DECL_COMDAT (newdecl) = 0;
2426
2427 new_template_info = NULL_TREE;
2428 if (DECL_LANG_SPECIFIC (newdecl) && DECL_LANG_SPECIFIC (olddecl))
2429 {
2430 bool new_redefines_gnu_inline = false;
2431
2432 if (new_defines_function
2433 && ((DECL_INTERFACE_KNOWN (olddecl)
2434 && TREE_CODE (olddecl) == FUNCTION_DECL)
2435 || (TREE_CODE (olddecl) == TEMPLATE_DECL
2436 && (TREE_CODE (DECL_TEMPLATE_RESULT (olddecl))
2437 == FUNCTION_DECL))))
2438 {
2439 tree fn = olddecl;
2440
2441 if (TREE_CODE (fn) == TEMPLATE_DECL)
2442 fn = DECL_TEMPLATE_RESULT (olddecl);
2443
2444 new_redefines_gnu_inline = GNU_INLINE_P (fn) && DECL_INITIAL (fn);
2445 }
2446
2447 if (!new_redefines_gnu_inline)
2448 {
2449 DECL_INTERFACE_KNOWN (newdecl) |= DECL_INTERFACE_KNOWN (olddecl);
2450 DECL_NOT_REALLY_EXTERN (newdecl) |= DECL_NOT_REALLY_EXTERN (olddecl);
2451 DECL_COMDAT (newdecl) |= DECL_COMDAT (olddecl);
2452 }
2453 DECL_TEMPLATE_INSTANTIATED (newdecl)
2454 |= DECL_TEMPLATE_INSTANTIATED (olddecl);
2455 DECL_ODR_USED (newdecl) |= DECL_ODR_USED (olddecl);
2456
2457 /* If the OLDDECL is an instantiation and/or specialization,
2458 then the NEWDECL must be too. But, it may not yet be marked
2459 as such if the caller has created NEWDECL, but has not yet
2460 figured out that it is a redeclaration. */
2461 if (!DECL_USE_TEMPLATE (newdecl))
2462 DECL_USE_TEMPLATE (newdecl) = DECL_USE_TEMPLATE (olddecl);
2463
2464 /* Don't really know how much of the language-specific
2465 values we should copy from old to new. */
2466 DECL_IN_AGGR_P (newdecl) = DECL_IN_AGGR_P (olddecl);
2467 DECL_INITIALIZED_IN_CLASS_P (newdecl)
2468 |= DECL_INITIALIZED_IN_CLASS_P (olddecl);
2469
2470 if (LANG_DECL_HAS_MIN (newdecl))
2471 {
2472 DECL_ACCESS (newdecl) = DECL_ACCESS (olddecl);
2473 if (DECL_TEMPLATE_INFO (newdecl))
2474 {
2475 new_template_info = DECL_TEMPLATE_INFO (newdecl);
2476 if (DECL_TEMPLATE_INSTANTIATION (olddecl)
2477 && DECL_TEMPLATE_SPECIALIZATION (newdecl))
2478 /* Remember the presence of explicit specialization args. */
2479 TINFO_USED_TEMPLATE_ID (DECL_TEMPLATE_INFO (olddecl))
2480 = TINFO_USED_TEMPLATE_ID (new_template_info);
2481 }
2482 DECL_TEMPLATE_INFO (newdecl) = DECL_TEMPLATE_INFO (olddecl);
2483 }
2484
2485 if (DECL_DECLARES_FUNCTION_P (newdecl))
2486 {
2487 /* Only functions have these fields. */
2488 DECL_NONCONVERTING_P (newdecl) = DECL_NONCONVERTING_P (olddecl);
2489 DECL_BEFRIENDING_CLASSES (newdecl)
2490 = chainon (DECL_BEFRIENDING_CLASSES (newdecl),
2491 DECL_BEFRIENDING_CLASSES (olddecl));
2492 /* DECL_THUNKS is only valid for virtual functions,
2493 otherwise it is a DECL_FRIEND_CONTEXT. */
2494 if (DECL_VIRTUAL_P (newdecl))
2495 SET_DECL_THUNKS (newdecl, DECL_THUNKS (olddecl));
2496 }
2497 else if (VAR_P (newdecl))
2498 {
2499 /* Only variables have this field. */
2500 if (VAR_HAD_UNKNOWN_BOUND (olddecl))
2501 SET_VAR_HAD_UNKNOWN_BOUND (newdecl);
2502 }
2503 }
2504
2505 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2506 {
2507 tree parm;
2508
2509 /* Merge parameter attributes. */
2510 tree oldarg, newarg;
2511 for (oldarg = DECL_ARGUMENTS(olddecl), newarg = DECL_ARGUMENTS(newdecl);
2512 oldarg && newarg;
2513 oldarg = DECL_CHAIN(oldarg), newarg = DECL_CHAIN(newarg))
2514 {
2515 DECL_ATTRIBUTES (newarg)
2516 = (*targetm.merge_decl_attributes) (oldarg, newarg);
2517 DECL_ATTRIBUTES (oldarg) = DECL_ATTRIBUTES (newarg);
2518 }
2519
2520 if (DECL_TEMPLATE_INSTANTIATION (olddecl)
2521 && !DECL_TEMPLATE_INSTANTIATION (newdecl))
2522 {
2523 /* If newdecl is not a specialization, then it is not a
2524 template-related function at all. And that means that we
2525 should have exited above, returning 0. */
2526 gcc_assert (DECL_TEMPLATE_SPECIALIZATION (newdecl));
2527
2528 if (DECL_ODR_USED (olddecl))
2529 /* From [temp.expl.spec]:
2530
2531 If a template, a member template or the member of a class
2532 template is explicitly specialized then that
2533 specialization shall be declared before the first use of
2534 that specialization that would cause an implicit
2535 instantiation to take place, in every translation unit in
2536 which such a use occurs. */
2537 error ("explicit specialization of %qD after first use",
2538 olddecl);
2539
2540 SET_DECL_TEMPLATE_SPECIALIZATION (olddecl);
2541 DECL_COMDAT (newdecl) = (TREE_PUBLIC (newdecl)
2542 && DECL_DECLARED_INLINE_P (newdecl));
2543
2544 /* Don't propagate visibility from the template to the
2545 specialization here. We'll do that in determine_visibility if
2546 appropriate. */
2547 DECL_VISIBILITY_SPECIFIED (olddecl) = 0;
2548
2549 /* [temp.expl.spec/14] We don't inline explicit specialization
2550 just because the primary template says so. */
2551 gcc_assert (!merge_attr);
2552
2553 DECL_DECLARED_INLINE_P (olddecl)
2554 = DECL_DECLARED_INLINE_P (newdecl);
2555
2556 DECL_DISREGARD_INLINE_LIMITS (olddecl)
2557 = DECL_DISREGARD_INLINE_LIMITS (newdecl);
2558
2559 DECL_UNINLINABLE (olddecl) = DECL_UNINLINABLE (newdecl);
2560 }
2561 else if (new_defines_function && DECL_INITIAL (olddecl))
2562 {
2563 /* Never inline re-defined extern inline functions.
2564 FIXME: this could be better handled by keeping both
2565 function as separate declarations. */
2566 DECL_UNINLINABLE (newdecl) = 1;
2567 }
2568 else
2569 {
2570 if (DECL_PENDING_INLINE_P (olddecl))
2571 {
2572 DECL_PENDING_INLINE_P (newdecl) = 1;
2573 DECL_PENDING_INLINE_INFO (newdecl)
2574 = DECL_PENDING_INLINE_INFO (olddecl);
2575 }
2576 else if (DECL_PENDING_INLINE_P (newdecl))
2577 ;
2578 else if (DECL_SAVED_AUTO_RETURN_TYPE (newdecl) == NULL)
2579 DECL_SAVED_AUTO_RETURN_TYPE (newdecl)
2580 = DECL_SAVED_AUTO_RETURN_TYPE (olddecl);
2581
2582 DECL_DECLARED_INLINE_P (newdecl) |= DECL_DECLARED_INLINE_P (olddecl);
2583
2584 DECL_UNINLINABLE (newdecl) = DECL_UNINLINABLE (olddecl)
2585 = (DECL_UNINLINABLE (newdecl) || DECL_UNINLINABLE (olddecl));
2586
2587 DECL_DISREGARD_INLINE_LIMITS (newdecl)
2588 = DECL_DISREGARD_INLINE_LIMITS (olddecl)
2589 = (DECL_DISREGARD_INLINE_LIMITS (newdecl)
2590 || DECL_DISREGARD_INLINE_LIMITS (olddecl));
2591 }
2592
2593 /* Preserve abstractness on cloned [cd]tors. */
2594 DECL_ABSTRACT_P (newdecl) = DECL_ABSTRACT_P (olddecl);
2595
2596 /* Update newdecl's parms to point at olddecl. */
2597 for (parm = DECL_ARGUMENTS (newdecl); parm;
2598 parm = DECL_CHAIN (parm))
2599 DECL_CONTEXT (parm) = olddecl;
2600
2601 if (! types_match)
2602 {
2603 SET_DECL_LANGUAGE (olddecl, DECL_LANGUAGE (newdecl));
2604 COPY_DECL_ASSEMBLER_NAME (newdecl, olddecl);
2605 COPY_DECL_RTL (newdecl, olddecl);
2606 }
2607 if (! types_match || new_defines_function)
2608 {
2609 /* These need to be copied so that the names are available.
2610 Note that if the types do match, we'll preserve inline
2611 info and other bits, but if not, we won't. */
2612 DECL_ARGUMENTS (olddecl) = DECL_ARGUMENTS (newdecl);
2613 DECL_RESULT (olddecl) = DECL_RESULT (newdecl);
2614 }
2615 /* If redeclaring a builtin function, it stays built in
2616 if newdecl is a gnu_inline definition, or if newdecl is just
2617 a declaration. */
2618 if (fndecl_built_in_p (olddecl)
2619 && (new_defines_function ? GNU_INLINE_P (newdecl) : types_match))
2620 {
2621 copy_decl_built_in_function (newdecl, olddecl);
2622 /* If we're keeping the built-in definition, keep the rtl,
2623 regardless of declaration matches. */
2624 COPY_DECL_RTL (olddecl, newdecl);
2625 if (DECL_BUILT_IN_CLASS (newdecl) == BUILT_IN_NORMAL)
2626 {
2627 enum built_in_function fncode = DECL_FUNCTION_CODE (newdecl);
2628 switch (fncode)
2629 {
2630 /* If a compatible prototype of these builtin functions
2631 is seen, assume the runtime implements it with the
2632 expected semantics. */
2633 case BUILT_IN_STPCPY:
2634 if (builtin_decl_explicit_p (fncode))
2635 set_builtin_decl_implicit_p (fncode, true);
2636 break;
2637 default:
2638 if (builtin_decl_explicit_p (fncode))
2639 set_builtin_decl_declared_p (fncode, true);
2640 break;
2641 }
2642
2643 copy_attributes_to_builtin (newdecl);
2644 }
2645 }
2646 if (new_defines_function)
2647 /* If defining a function declared with other language
2648 linkage, use the previously declared language linkage. */
2649 SET_DECL_LANGUAGE (newdecl, DECL_LANGUAGE (olddecl));
2650 else if (types_match)
2651 {
2652 DECL_RESULT (newdecl) = DECL_RESULT (olddecl);
2653 /* Don't clear out the arguments if we're just redeclaring a
2654 function. */
2655 if (DECL_ARGUMENTS (olddecl))
2656 DECL_ARGUMENTS (newdecl) = DECL_ARGUMENTS (olddecl);
2657 }
2658 }
2659 else if (TREE_CODE (newdecl) == NAMESPACE_DECL)
2660 NAMESPACE_LEVEL (newdecl) = NAMESPACE_LEVEL (olddecl);
2661
2662 /* Now preserve various other info from the definition. */
2663 TREE_ADDRESSABLE (newdecl) = TREE_ADDRESSABLE (olddecl);
2664 TREE_ASM_WRITTEN (newdecl) = TREE_ASM_WRITTEN (olddecl);
2665 DECL_COMMON (newdecl) = DECL_COMMON (olddecl);
2666 COPY_DECL_ASSEMBLER_NAME (olddecl, newdecl);
2667
2668 /* Warn about conflicting visibility specifications. */
2669 if (DECL_VISIBILITY_SPECIFIED (olddecl)
2670 && DECL_VISIBILITY_SPECIFIED (newdecl)
2671 && DECL_VISIBILITY (newdecl) != DECL_VISIBILITY (olddecl))
2672 {
2673 auto_diagnostic_group d;
2674 if (warning_at (newdecl_loc, OPT_Wattributes,
2675 "%qD: visibility attribute ignored because it "
2676 "conflicts with previous declaration", newdecl))
2677 inform (olddecl_loc,
2678 "previous declaration of %qD", olddecl);
2679 }
2680 /* Choose the declaration which specified visibility. */
2681 if (DECL_VISIBILITY_SPECIFIED (olddecl))
2682 {
2683 DECL_VISIBILITY (newdecl) = DECL_VISIBILITY (olddecl);
2684 DECL_VISIBILITY_SPECIFIED (newdecl) = 1;
2685 }
2686 /* Init priority used to be merged from newdecl to olddecl by the memcpy,
2687 so keep this behavior. */
2688 if (VAR_P (newdecl) && DECL_HAS_INIT_PRIORITY_P (newdecl))
2689 {
2690 SET_DECL_INIT_PRIORITY (olddecl, DECL_INIT_PRIORITY (newdecl));
2691 DECL_HAS_INIT_PRIORITY_P (olddecl) = 1;
2692 }
2693 /* Likewise for DECL_ALIGN, DECL_USER_ALIGN and DECL_PACKED. */
2694 if (DECL_ALIGN (olddecl) > DECL_ALIGN (newdecl))
2695 {
2696 SET_DECL_ALIGN (newdecl, DECL_ALIGN (olddecl));
2697 DECL_USER_ALIGN (newdecl) |= DECL_USER_ALIGN (olddecl);
2698 }
2699 DECL_USER_ALIGN (olddecl) = DECL_USER_ALIGN (newdecl);
2700 if (DECL_WARN_IF_NOT_ALIGN (olddecl)
2701 > DECL_WARN_IF_NOT_ALIGN (newdecl))
2702 SET_DECL_WARN_IF_NOT_ALIGN (newdecl,
2703 DECL_WARN_IF_NOT_ALIGN (olddecl));
2704 if (TREE_CODE (newdecl) == FIELD_DECL)
2705 DECL_PACKED (olddecl) = DECL_PACKED (newdecl);
2706
2707 /* The DECL_LANG_SPECIFIC information in OLDDECL will be replaced
2708 with that from NEWDECL below. */
2709 if (DECL_LANG_SPECIFIC (olddecl))
2710 {
2711 gcc_assert (DECL_LANG_SPECIFIC (olddecl)
2712 != DECL_LANG_SPECIFIC (newdecl));
2713 ggc_free (DECL_LANG_SPECIFIC (olddecl));
2714 }
2715
2716 /* Merge the USED information. */
2717 if (TREE_USED (olddecl))
2718 TREE_USED (newdecl) = 1;
2719 else if (TREE_USED (newdecl))
2720 TREE_USED (olddecl) = 1;
2721 if (VAR_P (newdecl))
2722 {
2723 if (DECL_READ_P (olddecl))
2724 DECL_READ_P (newdecl) = 1;
2725 else if (DECL_READ_P (newdecl))
2726 DECL_READ_P (olddecl) = 1;
2727 }
2728 if (DECL_PRESERVE_P (olddecl))
2729 DECL_PRESERVE_P (newdecl) = 1;
2730 else if (DECL_PRESERVE_P (newdecl))
2731 DECL_PRESERVE_P (olddecl) = 1;
2732
2733 /* Merge the DECL_FUNCTION_VERSIONED information. newdecl will be copied
2734 to olddecl and deleted. */
2735 if (TREE_CODE (newdecl) == FUNCTION_DECL
2736 && DECL_FUNCTION_VERSIONED (olddecl))
2737 {
2738 /* Set the flag for newdecl so that it gets copied to olddecl. */
2739 DECL_FUNCTION_VERSIONED (newdecl) = 1;
2740 /* newdecl will be purged after copying to olddecl and is no longer
2741 a version. */
2742 cgraph_node::delete_function_version_by_decl (newdecl);
2743 }
2744
2745 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2746 {
2747 int function_size;
2748 struct symtab_node *snode = symtab_node::get (olddecl);
2749
2750 function_size = sizeof (struct tree_decl_common);
2751
2752 memcpy ((char *) olddecl + sizeof (struct tree_common),
2753 (char *) newdecl + sizeof (struct tree_common),
2754 function_size - sizeof (struct tree_common));
2755
2756 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
2757 (char *) newdecl + sizeof (struct tree_decl_common),
2758 sizeof (struct tree_function_decl) - sizeof (struct tree_decl_common));
2759
2760 /* Preserve symtab node mapping. */
2761 olddecl->decl_with_vis.symtab_node = snode;
2762
2763 if (new_template_info)
2764 /* If newdecl is a template instantiation, it is possible that
2765 the following sequence of events has occurred:
2766
2767 o A friend function was declared in a class template. The
2768 class template was instantiated.
2769
2770 o The instantiation of the friend declaration was
2771 recorded on the instantiation list, and is newdecl.
2772
2773 o Later, however, instantiate_class_template called pushdecl
2774 on the newdecl to perform name injection. But, pushdecl in
2775 turn called duplicate_decls when it discovered that another
2776 declaration of a global function with the same name already
2777 existed.
2778
2779 o Here, in duplicate_decls, we decided to clobber newdecl.
2780
2781 If we're going to do that, we'd better make sure that
2782 olddecl, and not newdecl, is on the list of
2783 instantiations so that if we try to do the instantiation
2784 again we won't get the clobbered declaration. */
2785 reregister_specialization (newdecl,
2786 new_template_info,
2787 olddecl);
2788 }
2789 else
2790 {
2791 size_t size = tree_code_size (TREE_CODE (newdecl));
2792
2793 memcpy ((char *) olddecl + sizeof (struct tree_common),
2794 (char *) newdecl + sizeof (struct tree_common),
2795 sizeof (struct tree_decl_common) - sizeof (struct tree_common));
2796 switch (TREE_CODE (newdecl))
2797 {
2798 case LABEL_DECL:
2799 case VAR_DECL:
2800 case RESULT_DECL:
2801 case PARM_DECL:
2802 case FIELD_DECL:
2803 case TYPE_DECL:
2804 case CONST_DECL:
2805 {
2806 struct symtab_node *snode = NULL;
2807
2808 if (VAR_P (newdecl)
2809 && (TREE_STATIC (olddecl) || TREE_PUBLIC (olddecl)
2810 || DECL_EXTERNAL (olddecl)))
2811 snode = symtab_node::get (olddecl);
2812 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
2813 (char *) newdecl + sizeof (struct tree_decl_common),
2814 size - sizeof (struct tree_decl_common)
2815 + TREE_CODE_LENGTH (TREE_CODE (newdecl)) * sizeof (char *));
2816 if (VAR_P (newdecl))
2817 olddecl->decl_with_vis.symtab_node = snode;
2818 }
2819 break;
2820 default:
2821 memcpy ((char *) olddecl + sizeof (struct tree_decl_common),
2822 (char *) newdecl + sizeof (struct tree_decl_common),
2823 sizeof (struct tree_decl_non_common) - sizeof (struct tree_decl_common)
2824 + TREE_CODE_LENGTH (TREE_CODE (newdecl)) * sizeof (char *));
2825 break;
2826 }
2827 }
2828
2829 if (VAR_OR_FUNCTION_DECL_P (newdecl))
2830 {
2831 if (DECL_EXTERNAL (olddecl)
2832 || TREE_PUBLIC (olddecl)
2833 || TREE_STATIC (olddecl))
2834 {
2835 /* Merge the section attribute.
2836 We want to issue an error if the sections conflict but that must be
2837 done later in decl_attributes since we are called before attributes
2838 are assigned. */
2839 if (DECL_SECTION_NAME (newdecl) != NULL)
2840 set_decl_section_name (olddecl, DECL_SECTION_NAME (newdecl));
2841
2842 if (DECL_ONE_ONLY (newdecl))
2843 {
2844 struct symtab_node *oldsym, *newsym;
2845 if (TREE_CODE (olddecl) == FUNCTION_DECL)
2846 oldsym = cgraph_node::get_create (olddecl);
2847 else
2848 oldsym = varpool_node::get_create (olddecl);
2849 newsym = symtab_node::get (newdecl);
2850 oldsym->set_comdat_group (newsym->get_comdat_group ());
2851 }
2852 }
2853
2854 if (VAR_P (newdecl)
2855 && CP_DECL_THREAD_LOCAL_P (newdecl))
2856 {
2857 CP_DECL_THREAD_LOCAL_P (olddecl) = true;
2858 if (!processing_template_decl)
2859 set_decl_tls_model (olddecl, DECL_TLS_MODEL (newdecl));
2860 }
2861 }
2862
2863 DECL_UID (olddecl) = olddecl_uid;
2864 if (olddecl_friend)
2865 DECL_FRIEND_P (olddecl) = 1;
2866 if (hidden_friend)
2867 {
2868 DECL_ANTICIPATED (olddecl) = 1;
2869 DECL_HIDDEN_FRIEND_P (olddecl) = 1;
2870 }
2871
2872 /* NEWDECL contains the merged attribute lists.
2873 Update OLDDECL to be the same. */
2874 DECL_ATTRIBUTES (olddecl) = DECL_ATTRIBUTES (newdecl);
2875
2876 /* If OLDDECL had its DECL_RTL instantiated, re-invoke make_decl_rtl
2877 so that encode_section_info has a chance to look at the new decl
2878 flags and attributes. */
2879 if (DECL_RTL_SET_P (olddecl)
2880 && (TREE_CODE (olddecl) == FUNCTION_DECL
2881 || (VAR_P (olddecl)
2882 && TREE_STATIC (olddecl))))
2883 make_decl_rtl (olddecl);
2884
2885 /* The NEWDECL will no longer be needed. Because every out-of-class
2886 declaration of a member results in a call to duplicate_decls,
2887 freeing these nodes represents in a significant savings.
2888
2889 Before releasing the node, be sore to remove function from symbol
2890 table that might have been inserted there to record comdat group.
2891 Be sure to however do not free DECL_STRUCT_FUNCTION because this
2892 structure is shared in between newdecl and oldecl. */
2893 if (TREE_CODE (newdecl) == FUNCTION_DECL)
2894 DECL_STRUCT_FUNCTION (newdecl) = NULL;
2895 if (VAR_OR_FUNCTION_DECL_P (newdecl))
2896 {
2897 struct symtab_node *snode = symtab_node::get (newdecl);
2898 if (snode)
2899 snode->remove ();
2900 }
2901
2902 if (TREE_CODE (olddecl) == FUNCTION_DECL)
2903 {
2904 tree clone;
2905 FOR_EACH_CLONE (clone, olddecl)
2906 {
2907 DECL_ATTRIBUTES (clone) = DECL_ATTRIBUTES (olddecl);
2908 DECL_PRESERVE_P (clone) |= DECL_PRESERVE_P (olddecl);
2909 }
2910 }
2911
2912 /* Remove the associated constraints for newdecl, if any, before
2913 reclaiming memory. */
2914 if (flag_concepts)
2915 remove_constraints (newdecl);
2916
2917 ggc_free (newdecl);
2918
2919 return olddecl;
2920 }
2921
2922 /* Return zero if the declaration NEWDECL is valid
2923 when the declaration OLDDECL (assumed to be for the same name)
2924 has already been seen.
2925 Otherwise return an error message format string with a %s
2926 where the identifier should go. */
2927
2928 static const char *
redeclaration_error_message(tree newdecl,tree olddecl)2929 redeclaration_error_message (tree newdecl, tree olddecl)
2930 {
2931 if (TREE_CODE (newdecl) == TYPE_DECL)
2932 {
2933 /* Because C++ can put things into name space for free,
2934 constructs like "typedef struct foo { ... } foo"
2935 would look like an erroneous redeclaration. */
2936 if (same_type_p (TREE_TYPE (newdecl), TREE_TYPE (olddecl)))
2937 return NULL;
2938 else
2939 return G_("redefinition of %q#D");
2940 }
2941 else if (TREE_CODE (newdecl) == FUNCTION_DECL)
2942 {
2943 /* If this is a pure function, its olddecl will actually be
2944 the original initialization to `0' (which we force to call
2945 abort()). Don't complain about redefinition in this case. */
2946 if (DECL_LANG_SPECIFIC (olddecl) && DECL_PURE_VIRTUAL_P (olddecl)
2947 && DECL_INITIAL (olddecl) == NULL_TREE)
2948 return NULL;
2949
2950 /* If both functions come from different namespaces, this is not
2951 a redeclaration - this is a conflict with a used function. */
2952 if (DECL_NAMESPACE_SCOPE_P (olddecl)
2953 && DECL_CONTEXT (olddecl) != DECL_CONTEXT (newdecl)
2954 && ! decls_match (olddecl, newdecl))
2955 return G_("%qD conflicts with used function");
2956
2957 /* We'll complain about linkage mismatches in
2958 warn_extern_redeclared_static. */
2959
2960 /* Defining the same name twice is no good. */
2961 if (decl_defined_p (olddecl)
2962 && decl_defined_p (newdecl))
2963 {
2964 if (DECL_NAME (olddecl) == NULL_TREE)
2965 return G_("%q#D not declared in class");
2966 else if (!GNU_INLINE_P (olddecl)
2967 || GNU_INLINE_P (newdecl))
2968 return G_("redefinition of %q#D");
2969 }
2970
2971 if (DECL_DECLARED_INLINE_P (olddecl) && DECL_DECLARED_INLINE_P (newdecl))
2972 {
2973 bool olda = GNU_INLINE_P (olddecl);
2974 bool newa = GNU_INLINE_P (newdecl);
2975
2976 if (olda != newa)
2977 {
2978 if (newa)
2979 return G_("%q+D redeclared inline with "
2980 "%<gnu_inline%> attribute");
2981 else
2982 return G_("%q+D redeclared inline without "
2983 "%<gnu_inline%> attribute");
2984 }
2985 }
2986
2987 /* [class.compare.default]: A definition of a comparison operator as
2988 defaulted that appears in a class shall be the first declaration of
2989 that function. */
2990 special_function_kind sfk = special_function_p (olddecl);
2991 if (sfk == sfk_comparison && DECL_DEFAULTED_FN (newdecl))
2992 return G_("comparison operator %q+D defaulted after "
2993 "its first declaration");
2994
2995 check_abi_tag_redeclaration
2996 (olddecl, lookup_attribute ("abi_tag", DECL_ATTRIBUTES (olddecl)),
2997 lookup_attribute ("abi_tag", DECL_ATTRIBUTES (newdecl)));
2998
2999 return NULL;
3000 }
3001 else if (TREE_CODE (newdecl) == TEMPLATE_DECL)
3002 {
3003 tree nt, ot;
3004
3005 if (TREE_CODE (DECL_TEMPLATE_RESULT (newdecl)) == CONCEPT_DECL)
3006 return G_("redefinition of %q#D");
3007
3008 if (TREE_CODE (DECL_TEMPLATE_RESULT (newdecl)) != FUNCTION_DECL)
3009 return redeclaration_error_message (DECL_TEMPLATE_RESULT (newdecl),
3010 DECL_TEMPLATE_RESULT (olddecl));
3011
3012 if (DECL_TEMPLATE_RESULT (newdecl) == DECL_TEMPLATE_RESULT (olddecl))
3013 return NULL;
3014
3015 nt = DECL_TEMPLATE_RESULT (newdecl);
3016 if (DECL_TEMPLATE_INFO (nt))
3017 nt = DECL_TEMPLATE_RESULT (template_for_substitution (nt));
3018 ot = DECL_TEMPLATE_RESULT (olddecl);
3019 if (DECL_TEMPLATE_INFO (ot))
3020 ot = DECL_TEMPLATE_RESULT (template_for_substitution (ot));
3021 if (DECL_INITIAL (nt) && DECL_INITIAL (ot)
3022 && (!GNU_INLINE_P (ot) || GNU_INLINE_P (nt)))
3023 return G_("redefinition of %q#D");
3024
3025 if (DECL_DECLARED_INLINE_P (ot) && DECL_DECLARED_INLINE_P (nt))
3026 {
3027 bool olda = GNU_INLINE_P (ot);
3028 bool newa = GNU_INLINE_P (nt);
3029
3030 if (olda != newa)
3031 {
3032 if (newa)
3033 return G_("%q+D redeclared inline with "
3034 "%<gnu_inline%> attribute");
3035 else
3036 return G_("%q+D redeclared inline without "
3037 "%<gnu_inline%> attribute");
3038 }
3039 }
3040
3041 /* Core issue #226 (C++0x):
3042
3043 If a friend function template declaration specifies a
3044 default template-argument, that declaration shall be a
3045 definition and shall be the only declaration of the
3046 function template in the translation unit. */
3047 if ((cxx_dialect != cxx98)
3048 && TREE_CODE (ot) == FUNCTION_DECL && DECL_FRIEND_P (ot)
3049 && !check_default_tmpl_args (nt, DECL_TEMPLATE_PARMS (newdecl),
3050 /*is_primary=*/true,
3051 /*is_partial=*/false,
3052 /*is_friend_decl=*/2))
3053 return G_("redeclaration of friend %q#D "
3054 "may not have default template arguments");
3055
3056 return NULL;
3057 }
3058 else if (VAR_P (newdecl)
3059 && CP_DECL_THREAD_LOCAL_P (newdecl) != CP_DECL_THREAD_LOCAL_P (olddecl)
3060 && (! DECL_LANG_SPECIFIC (olddecl)
3061 || ! CP_DECL_THREADPRIVATE_P (olddecl)
3062 || CP_DECL_THREAD_LOCAL_P (newdecl)))
3063 {
3064 /* Only variables can be thread-local, and all declarations must
3065 agree on this property. */
3066 if (CP_DECL_THREAD_LOCAL_P (newdecl))
3067 return G_("thread-local declaration of %q#D follows "
3068 "non-thread-local declaration");
3069 else
3070 return G_("non-thread-local declaration of %q#D follows "
3071 "thread-local declaration");
3072 }
3073 else if (toplevel_bindings_p () || DECL_NAMESPACE_SCOPE_P (newdecl))
3074 {
3075 /* The objects have been declared at namespace scope. If either
3076 is a member of an anonymous union, then this is an invalid
3077 redeclaration. For example:
3078
3079 int i;
3080 union { int i; };
3081
3082 is invalid. */
3083 if ((VAR_P (newdecl) && DECL_ANON_UNION_VAR_P (newdecl))
3084 || (VAR_P (olddecl) && DECL_ANON_UNION_VAR_P (olddecl)))
3085 return G_("redeclaration of %q#D");
3086 /* If at least one declaration is a reference, there is no
3087 conflict. For example:
3088
3089 int i = 3;
3090 extern int i;
3091
3092 is valid. */
3093 if (DECL_EXTERNAL (newdecl) || DECL_EXTERNAL (olddecl))
3094 return NULL;
3095
3096 /* Static data member declared outside a class definition
3097 if the variable is defined within the class with constexpr
3098 specifier is declaration rather than definition (and
3099 deprecated). */
3100 if (cxx_dialect >= cxx17
3101 && VAR_P (olddecl)
3102 && DECL_CLASS_SCOPE_P (olddecl)
3103 && DECL_DECLARED_CONSTEXPR_P (olddecl)
3104 && !DECL_INITIAL (newdecl))
3105 {
3106 DECL_EXTERNAL (newdecl) = 1;
3107 /* For now, only warn with explicit -Wdeprecated. */
3108 if (global_options_set.x_warn_deprecated)
3109 {
3110 auto_diagnostic_group d;
3111 if (warning_at (DECL_SOURCE_LOCATION (newdecl), OPT_Wdeprecated,
3112 "redundant redeclaration of %<constexpr%> "
3113 "static data member %qD", newdecl))
3114 inform (DECL_SOURCE_LOCATION (olddecl),
3115 "previous declaration of %qD", olddecl);
3116 }
3117 return NULL;
3118 }
3119
3120 /* Reject two definitions. */
3121 return G_("redefinition of %q#D");
3122 }
3123 else
3124 {
3125 /* Objects declared with block scope: */
3126 /* Reject two definitions, and reject a definition
3127 together with an external reference. */
3128 if (!(DECL_EXTERNAL (newdecl) && DECL_EXTERNAL (olddecl)))
3129 return G_("redeclaration of %q#D");
3130 return NULL;
3131 }
3132 }
3133
3134
3135 /* Hash and equality functions for the named_label table. */
3136
3137 hashval_t
hash(const value_type entry)3138 named_label_hash::hash (const value_type entry)
3139 {
3140 return IDENTIFIER_HASH_VALUE (entry->name);
3141 }
3142
3143 bool
equal(const value_type entry,compare_type name)3144 named_label_hash::equal (const value_type entry, compare_type name)
3145 {
3146 return name == entry->name;
3147 }
3148
3149 /* Look for a label named ID in the current function. If one cannot
3150 be found, create one. Return the named_label_entry, or NULL on
3151 failure. */
3152
3153 static named_label_entry *
lookup_label_1(tree id,bool making_local_p)3154 lookup_label_1 (tree id, bool making_local_p)
3155 {
3156 /* You can't use labels at global scope. */
3157 if (current_function_decl == NULL_TREE)
3158 {
3159 error ("label %qE referenced outside of any function", id);
3160 return NULL;
3161 }
3162
3163 if (!named_labels)
3164 named_labels = hash_table<named_label_hash>::create_ggc (13);
3165
3166 hashval_t hash = IDENTIFIER_HASH_VALUE (id);
3167 named_label_entry **slot
3168 = named_labels->find_slot_with_hash (id, hash, INSERT);
3169 named_label_entry *old = *slot;
3170
3171 if (old && old->label_decl)
3172 {
3173 if (!making_local_p)
3174 return old;
3175
3176 if (old->binding_level == current_binding_level)
3177 {
3178 error ("local label %qE conflicts with existing label", id);
3179 inform (DECL_SOURCE_LOCATION (old->label_decl), "previous label");
3180 return NULL;
3181 }
3182 }
3183
3184 /* We are making a new decl, create or reuse the named_label_entry */
3185 named_label_entry *ent = NULL;
3186 if (old && !old->label_decl)
3187 ent = old;
3188 else
3189 {
3190 ent = ggc_cleared_alloc<named_label_entry> ();
3191 ent->name = id;
3192 ent->outer = old;
3193 *slot = ent;
3194 }
3195
3196 /* Now create the LABEL_DECL. */
3197 tree decl = build_decl (input_location, LABEL_DECL, id, void_type_node);
3198
3199 DECL_CONTEXT (decl) = current_function_decl;
3200 SET_DECL_MODE (decl, VOIDmode);
3201 if (making_local_p)
3202 {
3203 C_DECLARED_LABEL_FLAG (decl) = true;
3204 DECL_CHAIN (decl) = current_binding_level->names;
3205 current_binding_level->names = decl;
3206 }
3207
3208 ent->label_decl = decl;
3209
3210 return ent;
3211 }
3212
3213 /* Wrapper for lookup_label_1. */
3214
3215 tree
lookup_label(tree id)3216 lookup_label (tree id)
3217 {
3218 bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
3219 named_label_entry *ent = lookup_label_1 (id, false);
3220 timevar_cond_stop (TV_NAME_LOOKUP, subtime);
3221 return ent ? ent->label_decl : NULL_TREE;
3222 }
3223
3224 tree
declare_local_label(tree id)3225 declare_local_label (tree id)
3226 {
3227 bool subtime = timevar_cond_start (TV_NAME_LOOKUP);
3228 named_label_entry *ent = lookup_label_1 (id, true);
3229 timevar_cond_stop (TV_NAME_LOOKUP, subtime);
3230 return ent ? ent->label_decl : NULL_TREE;
3231 }
3232
3233 /* Returns nonzero if it is ill-formed to jump past the declaration of
3234 DECL. Returns 2 if it's also a real problem. */
3235
3236 static int
decl_jump_unsafe(tree decl)3237 decl_jump_unsafe (tree decl)
3238 {
3239 /* [stmt.dcl]/3: A program that jumps from a point where a local variable
3240 with automatic storage duration is not in scope to a point where it is
3241 in scope is ill-formed unless the variable has scalar type, class type
3242 with a trivial default constructor and a trivial destructor, a
3243 cv-qualified version of one of these types, or an array of one of the
3244 preceding types and is declared without an initializer (8.5). */
3245 tree type = TREE_TYPE (decl);
3246
3247 if (!VAR_P (decl) || TREE_STATIC (decl)
3248 || type == error_mark_node)
3249 return 0;
3250
3251 if (DECL_NONTRIVIALLY_INITIALIZED_P (decl)
3252 || variably_modified_type_p (type, NULL_TREE))
3253 return 2;
3254
3255 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
3256 return 1;
3257
3258 return 0;
3259 }
3260
3261 /* A subroutine of check_previous_goto_1 and check_goto to identify a branch
3262 to the user. */
3263
3264 static bool
identify_goto(tree decl,location_t loc,const location_t * locus,diagnostic_t diag_kind)3265 identify_goto (tree decl, location_t loc, const location_t *locus,
3266 diagnostic_t diag_kind)
3267 {
3268 bool complained
3269 = emit_diagnostic (diag_kind, loc, 0,
3270 decl ? N_("jump to label %qD")
3271 : N_("jump to case label"), decl);
3272 if (complained && locus)
3273 inform (*locus, " from here");
3274 return complained;
3275 }
3276
3277 /* Check that a single previously seen jump to a newly defined label
3278 is OK. DECL is the LABEL_DECL or 0; LEVEL is the binding_level for
3279 the jump context; NAMES are the names in scope in LEVEL at the jump
3280 context; LOCUS is the source position of the jump or 0. Returns
3281 true if all is well. */
3282
3283 static bool
check_previous_goto_1(tree decl,cp_binding_level * level,tree names,bool exited_omp,const location_t * locus)3284 check_previous_goto_1 (tree decl, cp_binding_level* level, tree names,
3285 bool exited_omp, const location_t *locus)
3286 {
3287 cp_binding_level *b;
3288 bool complained = false;
3289 int identified = 0;
3290 bool saw_eh = false, saw_omp = false, saw_tm = false, saw_cxif = false;
3291
3292 if (exited_omp)
3293 {
3294 complained = identify_goto (decl, input_location, locus, DK_ERROR);
3295 if (complained)
3296 inform (input_location, " exits OpenMP structured block");
3297 saw_omp = true;
3298 identified = 2;
3299 }
3300
3301 for (b = current_binding_level; b ; b = b->level_chain)
3302 {
3303 tree new_decls, old_decls = (b == level ? names : NULL_TREE);
3304
3305 for (new_decls = b->names; new_decls != old_decls;
3306 new_decls = (DECL_P (new_decls) ? DECL_CHAIN (new_decls)
3307 : TREE_CHAIN (new_decls)))
3308 {
3309 int problem = decl_jump_unsafe (new_decls);
3310 if (! problem)
3311 continue;
3312
3313 if (!identified)
3314 {
3315 complained = identify_goto (decl, input_location, locus,
3316 problem > 1
3317 ? DK_ERROR : DK_PERMERROR);
3318 identified = 1;
3319 }
3320 if (complained)
3321 {
3322 if (problem > 1)
3323 inform (DECL_SOURCE_LOCATION (new_decls),
3324 " crosses initialization of %q#D", new_decls);
3325 else
3326 inform (DECL_SOURCE_LOCATION (new_decls),
3327 " enters scope of %q#D, which has "
3328 "non-trivial destructor", new_decls);
3329 }
3330 }
3331
3332 if (b == level)
3333 break;
3334
3335 const char *inf = NULL;
3336 location_t loc = input_location;
3337 switch (b->kind)
3338 {
3339 case sk_try:
3340 if (!saw_eh)
3341 inf = G_(" enters %<try%> block");
3342 saw_eh = true;
3343 break;
3344
3345 case sk_catch:
3346 if (!saw_eh)
3347 inf = G_(" enters %<catch%> block");
3348 saw_eh = true;
3349 break;
3350
3351 case sk_omp:
3352 if (!saw_omp)
3353 inf = G_(" enters OpenMP structured block");
3354 saw_omp = true;
3355 break;
3356
3357 case sk_transaction:
3358 if (!saw_tm)
3359 inf = G_(" enters synchronized or atomic statement");
3360 saw_tm = true;
3361 break;
3362
3363 case sk_block:
3364 if (!saw_cxif && level_for_constexpr_if (b->level_chain))
3365 {
3366 inf = G_(" enters %<constexpr if%> statement");
3367 loc = EXPR_LOCATION (b->level_chain->this_entity);
3368 saw_cxif = true;
3369 }
3370 break;
3371
3372 default:
3373 break;
3374 }
3375
3376 if (inf)
3377 {
3378 if (identified < 2)
3379 complained = identify_goto (decl, input_location, locus, DK_ERROR);
3380 identified = 2;
3381 if (complained)
3382 inform (loc, inf);
3383 }
3384 }
3385
3386 return !identified;
3387 }
3388
3389 static void
check_previous_goto(tree decl,struct named_label_use_entry * use)3390 check_previous_goto (tree decl, struct named_label_use_entry *use)
3391 {
3392 check_previous_goto_1 (decl, use->binding_level,
3393 use->names_in_scope, use->in_omp_scope,
3394 &use->o_goto_locus);
3395 }
3396
3397 static bool
check_switch_goto(cp_binding_level * level)3398 check_switch_goto (cp_binding_level* level)
3399 {
3400 return check_previous_goto_1 (NULL_TREE, level, level->names, false, NULL);
3401 }
3402
3403 /* Check that a new jump to a label DECL is OK. Called by
3404 finish_goto_stmt. */
3405
3406 void
check_goto(tree decl)3407 check_goto (tree decl)
3408 {
3409 /* We can't know where a computed goto is jumping.
3410 So we assume that it's OK. */
3411 if (TREE_CODE (decl) != LABEL_DECL)
3412 return;
3413
3414 /* We didn't record any information about this label when we created it,
3415 and there's not much point since it's trivial to analyze as a return. */
3416 if (decl == cdtor_label)
3417 return;
3418
3419 hashval_t hash = IDENTIFIER_HASH_VALUE (DECL_NAME (decl));
3420 named_label_entry **slot
3421 = named_labels->find_slot_with_hash (DECL_NAME (decl), hash, NO_INSERT);
3422 named_label_entry *ent = *slot;
3423
3424 /* If the label hasn't been defined yet, defer checking. */
3425 if (! DECL_INITIAL (decl))
3426 {
3427 /* Don't bother creating another use if the last goto had the
3428 same data, and will therefore create the same set of errors. */
3429 if (ent->uses
3430 && ent->uses->names_in_scope == current_binding_level->names)
3431 return;
3432
3433 named_label_use_entry *new_use
3434 = ggc_alloc<named_label_use_entry> ();
3435 new_use->binding_level = current_binding_level;
3436 new_use->names_in_scope = current_binding_level->names;
3437 new_use->o_goto_locus = input_location;
3438 new_use->in_omp_scope = false;
3439
3440 new_use->next = ent->uses;
3441 ent->uses = new_use;
3442 return;
3443 }
3444
3445 bool saw_catch = false, complained = false;
3446 int identified = 0;
3447 tree bad;
3448 unsigned ix;
3449
3450 if (ent->in_try_scope || ent->in_catch_scope || ent->in_transaction_scope
3451 || ent->in_constexpr_if
3452 || ent->in_omp_scope || !vec_safe_is_empty (ent->bad_decls))
3453 {
3454 diagnostic_t diag_kind = DK_PERMERROR;
3455 if (ent->in_try_scope || ent->in_catch_scope || ent->in_constexpr_if
3456 || ent->in_transaction_scope || ent->in_omp_scope)
3457 diag_kind = DK_ERROR;
3458 complained = identify_goto (decl, DECL_SOURCE_LOCATION (decl),
3459 &input_location, diag_kind);
3460 identified = 1 + (diag_kind == DK_ERROR);
3461 }
3462
3463 FOR_EACH_VEC_SAFE_ELT (ent->bad_decls, ix, bad)
3464 {
3465 int u = decl_jump_unsafe (bad);
3466
3467 if (u > 1 && DECL_ARTIFICIAL (bad))
3468 {
3469 /* Can't skip init of __exception_info. */
3470 if (identified == 1)
3471 {
3472 complained = identify_goto (decl, DECL_SOURCE_LOCATION (decl),
3473 &input_location, DK_ERROR);
3474 identified = 2;
3475 }
3476 if (complained)
3477 inform (DECL_SOURCE_LOCATION (bad), " enters %<catch%> block");
3478 saw_catch = true;
3479 }
3480 else if (complained)
3481 {
3482 if (u > 1)
3483 inform (DECL_SOURCE_LOCATION (bad),
3484 " skips initialization of %q#D", bad);
3485 else
3486 inform (DECL_SOURCE_LOCATION (bad),
3487 " enters scope of %q#D which has "
3488 "non-trivial destructor", bad);
3489 }
3490 }
3491
3492 if (complained)
3493 {
3494 if (ent->in_try_scope)
3495 inform (input_location, " enters %<try%> block");
3496 else if (ent->in_catch_scope && !saw_catch)
3497 inform (input_location, " enters %<catch%> block");
3498 else if (ent->in_transaction_scope)
3499 inform (input_location, " enters synchronized or atomic statement");
3500 else if (ent->in_constexpr_if)
3501 inform (input_location, " enters %<constexpr if%> statement");
3502 }
3503
3504 if (ent->in_omp_scope)
3505 {
3506 if (complained)
3507 inform (input_location, " enters OpenMP structured block");
3508 }
3509 else if (flag_openmp)
3510 for (cp_binding_level *b = current_binding_level; b ; b = b->level_chain)
3511 {
3512 if (b == ent->binding_level)
3513 break;
3514 if (b->kind == sk_omp)
3515 {
3516 if (identified < 2)
3517 {
3518 complained = identify_goto (decl,
3519 DECL_SOURCE_LOCATION (decl),
3520 &input_location, DK_ERROR);
3521 identified = 2;
3522 }
3523 if (complained)
3524 inform (input_location, " exits OpenMP structured block");
3525 break;
3526 }
3527 }
3528 }
3529
3530 /* Check that a return is ok wrt OpenMP structured blocks.
3531 Called by finish_return_stmt. Returns true if all is well. */
3532
3533 bool
check_omp_return(void)3534 check_omp_return (void)
3535 {
3536 for (cp_binding_level *b = current_binding_level; b ; b = b->level_chain)
3537 if (b->kind == sk_omp)
3538 {
3539 error ("invalid exit from OpenMP structured block");
3540 return false;
3541 }
3542 else if (b->kind == sk_function_parms)
3543 break;
3544 return true;
3545 }
3546
3547 /* Define a label, specifying the location in the source file.
3548 Return the LABEL_DECL node for the label. */
3549
3550 static tree
define_label_1(location_t location,tree name)3551 define_label_1 (location_t location, tree name)
3552 {
3553 /* After labels, make any new cleanups in the function go into their
3554 own new (temporary) binding contour. */
3555 for (cp_binding_level *p = current_binding_level;
3556 p->kind != sk_function_parms;
3557 p = p->level_chain)
3558 p->more_cleanups_ok = 0;
3559
3560 named_label_entry *ent = lookup_label_1 (name, false);
3561 tree decl = ent->label_decl;
3562
3563 if (DECL_INITIAL (decl) != NULL_TREE)
3564 {
3565 error ("duplicate label %qD", decl);
3566 return error_mark_node;
3567 }
3568 else
3569 {
3570 /* Mark label as having been defined. */
3571 DECL_INITIAL (decl) = error_mark_node;
3572 /* Say where in the source. */
3573 DECL_SOURCE_LOCATION (decl) = location;
3574
3575 ent->binding_level = current_binding_level;
3576 ent->names_in_scope = current_binding_level->names;
3577
3578 for (named_label_use_entry *use = ent->uses; use; use = use->next)
3579 check_previous_goto (decl, use);
3580 ent->uses = NULL;
3581 }
3582
3583 return decl;
3584 }
3585
3586 /* Wrapper for define_label_1. */
3587
3588 tree
define_label(location_t location,tree name)3589 define_label (location_t location, tree name)
3590 {
3591 bool running = timevar_cond_start (TV_NAME_LOOKUP);
3592 tree ret = define_label_1 (location, name);
3593 timevar_cond_stop (TV_NAME_LOOKUP, running);
3594 return ret;
3595 }
3596
3597
3598 struct cp_switch
3599 {
3600 cp_binding_level *level;
3601 struct cp_switch *next;
3602 /* The SWITCH_STMT being built. */
3603 tree switch_stmt;
3604 /* A splay-tree mapping the low element of a case range to the high
3605 element, or NULL_TREE if there is no high element. Used to
3606 determine whether or not a new case label duplicates an old case
3607 label. We need a tree, rather than simply a hash table, because
3608 of the GNU case range extension. */
3609 splay_tree cases;
3610 /* Remember whether a default: case label has been seen. */
3611 bool has_default_p;
3612 /* Remember whether a BREAK_STMT has been seen in this SWITCH_STMT. */
3613 bool break_stmt_seen_p;
3614 /* Set if inside of {FOR,DO,WHILE}_BODY nested inside of a switch,
3615 where BREAK_STMT doesn't belong to the SWITCH_STMT. */
3616 bool in_loop_body_p;
3617 };
3618
3619 /* A stack of the currently active switch statements. The innermost
3620 switch statement is on the top of the stack. There is no need to
3621 mark the stack for garbage collection because it is only active
3622 during the processing of the body of a function, and we never
3623 collect at that point. */
3624
3625 static struct cp_switch *switch_stack;
3626
3627 /* Called right after a switch-statement condition is parsed.
3628 SWITCH_STMT is the switch statement being parsed. */
3629
3630 void
push_switch(tree switch_stmt)3631 push_switch (tree switch_stmt)
3632 {
3633 struct cp_switch *p = XNEW (struct cp_switch);
3634 p->level = current_binding_level;
3635 p->next = switch_stack;
3636 p->switch_stmt = switch_stmt;
3637 p->cases = splay_tree_new (case_compare, NULL, NULL);
3638 p->has_default_p = false;
3639 p->break_stmt_seen_p = false;
3640 p->in_loop_body_p = false;
3641 switch_stack = p;
3642 }
3643
3644 void
pop_switch(void)3645 pop_switch (void)
3646 {
3647 struct cp_switch *cs = switch_stack;
3648
3649 /* Emit warnings as needed. */
3650 location_t switch_location = cp_expr_loc_or_input_loc (cs->switch_stmt);
3651 tree cond = SWITCH_STMT_COND (cs->switch_stmt);
3652 const bool bool_cond_p
3653 = (SWITCH_STMT_TYPE (cs->switch_stmt)
3654 && TREE_CODE (SWITCH_STMT_TYPE (cs->switch_stmt)) == BOOLEAN_TYPE);
3655 if (!processing_template_decl)
3656 c_do_switch_warnings (cs->cases, switch_location,
3657 SWITCH_STMT_TYPE (cs->switch_stmt), cond,
3658 bool_cond_p);
3659
3660 /* For the benefit of block_may_fallthru remember if the switch body
3661 case labels cover all possible values and if there are break; stmts. */
3662 if (cs->has_default_p
3663 || (!processing_template_decl
3664 && c_switch_covers_all_cases_p (cs->cases,
3665 SWITCH_STMT_TYPE (cs->switch_stmt))))
3666 SWITCH_STMT_ALL_CASES_P (cs->switch_stmt) = 1;
3667 if (!cs->break_stmt_seen_p)
3668 SWITCH_STMT_NO_BREAK_P (cs->switch_stmt) = 1;
3669 /* Now that we're done with the switch warnings, set the switch type
3670 to the type of the condition if the index type was of scoped enum type.
3671 (Such types don't participate in the integer promotions.) We do this
3672 because of bit-fields whose declared type is a scoped enum type:
3673 gimplification will use the lowered index type, but convert the
3674 case values to SWITCH_STMT_TYPE, which would have been the declared type
3675 and verify_gimple_switch doesn't accept that. */
3676 if (is_bitfield_expr_with_lowered_type (cond))
3677 SWITCH_STMT_TYPE (cs->switch_stmt) = TREE_TYPE (cond);
3678 gcc_assert (!cs->in_loop_body_p);
3679 splay_tree_delete (cs->cases);
3680 switch_stack = switch_stack->next;
3681 free (cs);
3682 }
3683
3684 /* Note that a BREAK_STMT is about to be added. If it is inside of
3685 a SWITCH_STMT and not inside of a loop body inside of it, note
3686 in switch_stack we've seen a BREAK_STMT. */
3687
3688 void
note_break_stmt(void)3689 note_break_stmt (void)
3690 {
3691 if (switch_stack && !switch_stack->in_loop_body_p)
3692 switch_stack->break_stmt_seen_p = true;
3693 }
3694
3695 /* Note the start of processing of an iteration statement's body.
3696 The note_break_stmt function will do nothing while processing it.
3697 Return a flag that should be passed to note_iteration_stmt_body_end. */
3698
3699 bool
note_iteration_stmt_body_start(void)3700 note_iteration_stmt_body_start (void)
3701 {
3702 if (!switch_stack)
3703 return false;
3704 bool ret = switch_stack->in_loop_body_p;
3705 switch_stack->in_loop_body_p = true;
3706 return ret;
3707 }
3708
3709 /* Note the end of processing of an iteration statement's body. */
3710
3711 void
note_iteration_stmt_body_end(bool prev)3712 note_iteration_stmt_body_end (bool prev)
3713 {
3714 if (switch_stack)
3715 switch_stack->in_loop_body_p = prev;
3716 }
3717
3718 /* Convert a case constant VALUE in a switch to the type TYPE of the switch
3719 condition. Note that if TYPE and VALUE are already integral we don't
3720 really do the conversion because the language-independent
3721 warning/optimization code will work better that way. */
3722
3723 static tree
case_conversion(tree type,tree value)3724 case_conversion (tree type, tree value)
3725 {
3726 if (value == NULL_TREE)
3727 return value;
3728
3729 value = mark_rvalue_use (value);
3730
3731 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
3732 type = type_promotes_to (type);
3733
3734 tree ovalue = value;
3735 /* The constant-expression VALUE shall be a converted constant expression
3736 of the adjusted type of the switch condition, which doesn't allow
3737 narrowing conversions. */
3738 value = build_converted_constant_expr (type, value, tf_warning_or_error);
3739
3740 if (cxx_dialect >= cxx11
3741 && (SCOPED_ENUM_P (type)
3742 || !INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (ovalue))))
3743 /* Use the converted value. */;
3744 else
3745 /* The already integral case. */
3746 value = ovalue;
3747
3748 return cxx_constant_value (value);
3749 }
3750
3751 /* Note that we've seen a definition of a case label, and complain if this
3752 is a bad place for one. */
3753
3754 tree
finish_case_label(location_t loc,tree low_value,tree high_value)3755 finish_case_label (location_t loc, tree low_value, tree high_value)
3756 {
3757 tree cond, r;
3758 cp_binding_level *p;
3759 tree type;
3760
3761 if (low_value == NULL_TREE && high_value == NULL_TREE)
3762 switch_stack->has_default_p = true;
3763
3764 if (processing_template_decl)
3765 {
3766 tree label;
3767
3768 /* For templates, just add the case label; we'll do semantic
3769 analysis at instantiation-time. */
3770 label = build_decl (loc, LABEL_DECL, NULL_TREE, void_type_node);
3771 return add_stmt (build_case_label (low_value, high_value, label));
3772 }
3773
3774 /* Find the condition on which this switch statement depends. */
3775 cond = SWITCH_STMT_COND (switch_stack->switch_stmt);
3776 if (cond && TREE_CODE (cond) == TREE_LIST)
3777 cond = TREE_VALUE (cond);
3778
3779 if (!check_switch_goto (switch_stack->level))
3780 return error_mark_node;
3781
3782 type = SWITCH_STMT_TYPE (switch_stack->switch_stmt);
3783 if (type == error_mark_node)
3784 return error_mark_node;
3785
3786 low_value = case_conversion (type, low_value);
3787 high_value = case_conversion (type, high_value);
3788
3789 r = c_add_case_label (loc, switch_stack->cases, cond, low_value, high_value);
3790
3791 /* After labels, make any new cleanups in the function go into their
3792 own new (temporary) binding contour. */
3793 for (p = current_binding_level;
3794 p->kind != sk_function_parms;
3795 p = p->level_chain)
3796 p->more_cleanups_ok = 0;
3797
3798 return r;
3799 }
3800
3801 struct typename_info {
3802 tree scope;
3803 tree name;
3804 tree template_id;
3805 bool enum_p;
3806 bool class_p;
3807 };
3808
3809 struct typename_hasher : ggc_ptr_hash<tree_node>
3810 {
3811 typedef typename_info *compare_type;
3812
3813 /* Hash a TYPENAME_TYPE. */
3814
3815 static hashval_t
hashtypename_hasher3816 hash (tree t)
3817 {
3818 hashval_t hash;
3819
3820 hash = (htab_hash_pointer (TYPE_CONTEXT (t))
3821 ^ htab_hash_pointer (TYPE_IDENTIFIER (t)));
3822
3823 return hash;
3824 }
3825
3826 /* Compare two TYPENAME_TYPEs. */
3827
3828 static bool
equaltypename_hasher3829 equal (tree t1, const typename_info *t2)
3830 {
3831 return (TYPE_IDENTIFIER (t1) == t2->name
3832 && TYPE_CONTEXT (t1) == t2->scope
3833 && TYPENAME_TYPE_FULLNAME (t1) == t2->template_id
3834 && TYPENAME_IS_ENUM_P (t1) == t2->enum_p
3835 && TYPENAME_IS_CLASS_P (t1) == t2->class_p);
3836 }
3837 };
3838
3839 /* Build a TYPENAME_TYPE. If the type is `typename T::t', CONTEXT is
3840 the type of `T', NAME is the IDENTIFIER_NODE for `t'.
3841
3842 Returns the new TYPENAME_TYPE. */
3843
3844 static GTY (()) hash_table<typename_hasher> *typename_htab;
3845
3846 tree
build_typename_type(tree context,tree name,tree fullname,enum tag_types tag_type)3847 build_typename_type (tree context, tree name, tree fullname,
3848 enum tag_types tag_type)
3849 {
3850 tree t;
3851 tree d;
3852 typename_info ti;
3853 tree *e;
3854 hashval_t hash;
3855
3856 if (typename_htab == NULL)
3857 typename_htab = hash_table<typename_hasher>::create_ggc (61);
3858
3859 ti.scope = FROB_CONTEXT (context);
3860 ti.name = name;
3861 ti.template_id = fullname;
3862 ti.enum_p = tag_type == enum_type;
3863 ti.class_p = (tag_type == class_type
3864 || tag_type == record_type
3865 || tag_type == union_type);
3866 hash = (htab_hash_pointer (ti.scope)
3867 ^ htab_hash_pointer (ti.name));
3868
3869 /* See if we already have this type. */
3870 e = typename_htab->find_slot_with_hash (&ti, hash, INSERT);
3871 if (*e)
3872 t = *e;
3873 else
3874 {
3875 /* Build the TYPENAME_TYPE. */
3876 t = cxx_make_type (TYPENAME_TYPE);
3877 TYPE_CONTEXT (t) = ti.scope;
3878 TYPENAME_TYPE_FULLNAME (t) = ti.template_id;
3879 TYPENAME_IS_ENUM_P (t) = ti.enum_p;
3880 TYPENAME_IS_CLASS_P (t) = ti.class_p;
3881
3882 /* Build the corresponding TYPE_DECL. */
3883 d = build_decl (input_location, TYPE_DECL, name, t);
3884 TYPE_NAME (TREE_TYPE (d)) = d;
3885 TYPE_STUB_DECL (TREE_TYPE (d)) = d;
3886 DECL_CONTEXT (d) = FROB_CONTEXT (context);
3887 DECL_ARTIFICIAL (d) = 1;
3888
3889 /* Store it in the hash table. */
3890 *e = t;
3891
3892 /* TYPENAME_TYPEs must always be compared structurally, because
3893 they may or may not resolve down to another type depending on
3894 the currently open classes. */
3895 SET_TYPE_STRUCTURAL_EQUALITY (t);
3896 }
3897
3898 return t;
3899 }
3900
3901 /* Resolve `typename CONTEXT::NAME'. TAG_TYPE indicates the tag
3902 provided to name the type. Returns an appropriate type, unless an
3903 error occurs, in which case error_mark_node is returned. If we
3904 locate a non-artificial TYPE_DECL and TF_KEEP_TYPE_DECL is set, we
3905 return that, rather than the _TYPE it corresponds to, in other
3906 cases we look through the type decl. If TF_ERROR is set, complain
3907 about errors, otherwise be quiet. */
3908
3909 tree
make_typename_type(tree context,tree name,enum tag_types tag_type,tsubst_flags_t complain)3910 make_typename_type (tree context, tree name, enum tag_types tag_type,
3911 tsubst_flags_t complain)
3912 {
3913 tree fullname;
3914 tree t;
3915 bool want_template;
3916
3917 if (name == error_mark_node
3918 || context == NULL_TREE
3919 || context == error_mark_node)
3920 return error_mark_node;
3921
3922 if (TYPE_P (name))
3923 {
3924 if (!(TYPE_LANG_SPECIFIC (name)
3925 && (CLASSTYPE_IS_TEMPLATE (name)
3926 || CLASSTYPE_USE_TEMPLATE (name))))
3927 name = TYPE_IDENTIFIER (name);
3928 else
3929 /* Create a TEMPLATE_ID_EXPR for the type. */
3930 name = build_nt (TEMPLATE_ID_EXPR,
3931 CLASSTYPE_TI_TEMPLATE (name),
3932 CLASSTYPE_TI_ARGS (name));
3933 }
3934 else if (TREE_CODE (name) == TYPE_DECL)
3935 name = DECL_NAME (name);
3936
3937 fullname = name;
3938
3939 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
3940 {
3941 name = TREE_OPERAND (name, 0);
3942 if (DECL_TYPE_TEMPLATE_P (name))
3943 name = TREE_OPERAND (fullname, 0) = DECL_NAME (name);
3944 if (TREE_CODE (name) != IDENTIFIER_NODE)
3945 {
3946 if (complain & tf_error)
3947 error ("%qD is not a type", name);
3948 return error_mark_node;
3949 }
3950 }
3951 if (TREE_CODE (name) == TEMPLATE_DECL)
3952 {
3953 if (complain & tf_error)
3954 error ("%qD used without template arguments", name);
3955 return error_mark_node;
3956 }
3957 gcc_assert (identifier_p (name));
3958 gcc_assert (TYPE_P (context));
3959
3960 if (TREE_CODE (context) == TYPE_PACK_EXPANSION)
3961 /* This can happen for C++17 variadic using (c++/88986). */;
3962 else if (!MAYBE_CLASS_TYPE_P (context))
3963 {
3964 if (complain & tf_error)
3965 error ("%q#T is not a class", context);
3966 return error_mark_node;
3967 }
3968
3969 /* When the CONTEXT is a dependent type, NAME could refer to a
3970 dependent base class of CONTEXT. But look inside it anyway
3971 if CONTEXT is a currently open scope, in case it refers to a
3972 member of the current instantiation or a non-dependent base;
3973 lookup will stop when we hit a dependent base. */
3974 if (!dependent_scope_p (context))
3975 /* We should only set WANT_TYPE when we're a nested typename type.
3976 Then we can give better diagnostics if we find a non-type. */
3977 t = lookup_field (context, name, 2, /*want_type=*/true);
3978 else
3979 t = NULL_TREE;
3980
3981 if ((!t || TREE_CODE (t) == TREE_LIST) && dependent_type_p (context))
3982 return build_typename_type (context, name, fullname, tag_type);
3983
3984 want_template = TREE_CODE (fullname) == TEMPLATE_ID_EXPR;
3985
3986 if (!t)
3987 {
3988 if (complain & tf_error)
3989 {
3990 if (!COMPLETE_TYPE_P (context))
3991 cxx_incomplete_type_error (NULL_TREE, context);
3992 else
3993 error (want_template ? G_("no class template named %q#T in %q#T")
3994 : G_("no type named %q#T in %q#T"), name, context);
3995 }
3996 return error_mark_node;
3997 }
3998
3999 /* Pull out the template from an injected-class-name (or multiple). */
4000 if (want_template)
4001 t = maybe_get_template_decl_from_type_decl (t);
4002
4003 if (TREE_CODE (t) == TREE_LIST)
4004 {
4005 if (complain & tf_error)
4006 {
4007 error ("lookup of %qT in %qT is ambiguous", name, context);
4008 print_candidates (t);
4009 }
4010 return error_mark_node;
4011 }
4012
4013 if (want_template && !DECL_TYPE_TEMPLATE_P (t))
4014 {
4015 if (complain & tf_error)
4016 error ("%<typename %T::%D%> names %q#T, which is not a class template",
4017 context, name, t);
4018 return error_mark_node;
4019 }
4020 if (!want_template && TREE_CODE (t) != TYPE_DECL)
4021 {
4022 if (complain & tf_error)
4023 error ("%<typename %T::%D%> names %q#T, which is not a type",
4024 context, name, t);
4025 return error_mark_node;
4026 }
4027
4028 if (!perform_or_defer_access_check (TYPE_BINFO (context), t, t, complain))
4029 return error_mark_node;
4030
4031 /* If we are currently parsing a template and if T is a typedef accessed
4032 through CONTEXT then we need to remember and check access of T at
4033 template instantiation time. */
4034 add_typedef_to_current_template_for_access_check (t, context, input_location);
4035
4036 if (want_template)
4037 return lookup_template_class (t, TREE_OPERAND (fullname, 1),
4038 NULL_TREE, context,
4039 /*entering_scope=*/0,
4040 complain | tf_user);
4041
4042 if (DECL_ARTIFICIAL (t) || !(complain & tf_keep_type_decl))
4043 t = TREE_TYPE (t);
4044
4045 maybe_record_typedef_use (t);
4046
4047 return t;
4048 }
4049
4050 /* Resolve `CONTEXT::template NAME'. Returns a TEMPLATE_DECL if the name
4051 can be resolved or an UNBOUND_CLASS_TEMPLATE, unless an error occurs,
4052 in which case error_mark_node is returned.
4053
4054 If PARM_LIST is non-NULL, also make sure that the template parameter
4055 list of TEMPLATE_DECL matches.
4056
4057 If COMPLAIN zero, don't complain about any errors that occur. */
4058
4059 tree
make_unbound_class_template(tree context,tree name,tree parm_list,tsubst_flags_t complain)4060 make_unbound_class_template (tree context, tree name, tree parm_list,
4061 tsubst_flags_t complain)
4062 {
4063 tree t;
4064 tree d;
4065
4066 if (TYPE_P (name))
4067 name = TYPE_IDENTIFIER (name);
4068 else if (DECL_P (name))
4069 name = DECL_NAME (name);
4070 gcc_assert (identifier_p (name));
4071
4072 if (!dependent_type_p (context)
4073 || currently_open_class (context))
4074 {
4075 tree tmpl = NULL_TREE;
4076
4077 if (MAYBE_CLASS_TYPE_P (context))
4078 tmpl = lookup_field (context, name, 0, false);
4079
4080 if (tmpl && TREE_CODE (tmpl) == TYPE_DECL)
4081 tmpl = maybe_get_template_decl_from_type_decl (tmpl);
4082
4083 if (!tmpl || !DECL_TYPE_TEMPLATE_P (tmpl))
4084 {
4085 if (complain & tf_error)
4086 error ("no class template named %q#T in %q#T", name, context);
4087 return error_mark_node;
4088 }
4089
4090 if (parm_list
4091 && !comp_template_parms (DECL_TEMPLATE_PARMS (tmpl), parm_list))
4092 {
4093 if (complain & tf_error)
4094 {
4095 error ("template parameters do not match template %qD", tmpl);
4096 inform (DECL_SOURCE_LOCATION (tmpl),
4097 "%qD declared here", tmpl);
4098 }
4099 return error_mark_node;
4100 }
4101
4102 if (!perform_or_defer_access_check (TYPE_BINFO (context), tmpl, tmpl,
4103 complain))
4104 return error_mark_node;
4105
4106 return tmpl;
4107 }
4108
4109 /* Build the UNBOUND_CLASS_TEMPLATE. */
4110 t = cxx_make_type (UNBOUND_CLASS_TEMPLATE);
4111 TYPE_CONTEXT (t) = FROB_CONTEXT (context);
4112 TREE_TYPE (t) = NULL_TREE;
4113 SET_TYPE_STRUCTURAL_EQUALITY (t);
4114
4115 /* Build the corresponding TEMPLATE_DECL. */
4116 d = build_decl (input_location, TEMPLATE_DECL, name, t);
4117 TYPE_NAME (TREE_TYPE (d)) = d;
4118 TYPE_STUB_DECL (TREE_TYPE (d)) = d;
4119 DECL_CONTEXT (d) = FROB_CONTEXT (context);
4120 DECL_ARTIFICIAL (d) = 1;
4121 DECL_TEMPLATE_PARMS (d) = parm_list;
4122
4123 return t;
4124 }
4125
4126
4127
4128 /* Push the declarations of builtin types into the global namespace.
4129 RID_INDEX is the index of the builtin type in the array
4130 RID_POINTERS. NAME is the name used when looking up the builtin
4131 type. TYPE is the _TYPE node for the builtin type.
4132
4133 The calls to set_global_binding below should be
4134 eliminated. Built-in types should not be looked up name; their
4135 names are keywords that the parser can recognize. However, there
4136 is code in c-common.c that uses identifier_global_value to look up
4137 built-in types by name. */
4138
4139 void
record_builtin_type(enum rid rid_index,const char * name,tree type)4140 record_builtin_type (enum rid rid_index,
4141 const char* name,
4142 tree type)
4143 {
4144 tree decl = NULL_TREE;
4145
4146 if (name)
4147 {
4148 tree tname = get_identifier (name);
4149 tree tdecl = build_decl (BUILTINS_LOCATION, TYPE_DECL, tname, type);
4150 DECL_ARTIFICIAL (tdecl) = 1;
4151 set_global_binding (tdecl);
4152 decl = tdecl;
4153 }
4154
4155 if ((int) rid_index < (int) RID_MAX)
4156 if (tree rname = ridpointers[(int) rid_index])
4157 if (!decl || DECL_NAME (decl) != rname)
4158 {
4159 tree rdecl = build_decl (BUILTINS_LOCATION, TYPE_DECL, rname, type);
4160 DECL_ARTIFICIAL (rdecl) = 1;
4161 set_global_binding (rdecl);
4162 if (!decl)
4163 decl = rdecl;
4164 }
4165
4166 if (decl)
4167 {
4168 if (!TYPE_NAME (type))
4169 TYPE_NAME (type) = decl;
4170 debug_hooks->type_decl (decl, 0);
4171 }
4172 }
4173
4174 /* Push a type into the namespace so that the back ends ignore it. */
4175
4176 static void
record_unknown_type(tree type,const char * name)4177 record_unknown_type (tree type, const char* name)
4178 {
4179 tree decl = pushdecl (build_decl (UNKNOWN_LOCATION,
4180 TYPE_DECL, get_identifier (name), type));
4181 /* Make sure the "unknown type" typedecl gets ignored for debug info. */
4182 DECL_IGNORED_P (decl) = 1;
4183 TYPE_DECL_SUPPRESS_DEBUG (decl) = 1;
4184 TYPE_SIZE (type) = TYPE_SIZE (void_type_node);
4185 SET_TYPE_ALIGN (type, 1);
4186 TYPE_USER_ALIGN (type) = 0;
4187 SET_TYPE_MODE (type, TYPE_MODE (void_type_node));
4188 }
4189
4190 /* Create all the predefined identifiers. */
4191
4192 static void
initialize_predefined_identifiers(void)4193 initialize_predefined_identifiers (void)
4194 {
4195 struct predefined_identifier
4196 {
4197 const char *name; /* Name. */
4198 tree *node; /* Node to store it in. */
4199 cp_identifier_kind kind; /* Kind of identifier. */
4200 };
4201
4202 /* A table of identifiers to create at startup. */
4203 static const predefined_identifier predefined_identifiers[] = {
4204 {"C++", &lang_name_cplusplus, cik_normal},
4205 {"C", &lang_name_c, cik_normal},
4206 /* Some of these names have a trailing space so that it is
4207 impossible for them to conflict with names written by users. */
4208 {"__ct ", &ctor_identifier, cik_ctor},
4209 {"__ct_base ", &base_ctor_identifier, cik_ctor},
4210 {"__ct_comp ", &complete_ctor_identifier, cik_ctor},
4211 {"__dt ", &dtor_identifier, cik_dtor},
4212 {"__dt_base ", &base_dtor_identifier, cik_dtor},
4213 {"__dt_comp ", &complete_dtor_identifier, cik_dtor},
4214 {"__dt_del ", &deleting_dtor_identifier, cik_dtor},
4215 {"__conv_op ", &conv_op_identifier, cik_conv_op},
4216 {"__in_chrg", &in_charge_identifier, cik_normal},
4217 {"this", &this_identifier, cik_normal},
4218 {"__delta", &delta_identifier, cik_normal},
4219 {"__pfn", &pfn_identifier, cik_normal},
4220 {"_vptr", &vptr_identifier, cik_normal},
4221 {"__vtt_parm", &vtt_parm_identifier, cik_normal},
4222 {"::", &global_identifier, cik_normal},
4223 /* The demangler expects anonymous namespaces to be called
4224 something starting with '_GLOBAL__N_'. It no longer needs
4225 to be unique to the TU. */
4226 {"_GLOBAL__N_1", &anon_identifier, cik_normal},
4227 {"auto", &auto_identifier, cik_normal},
4228 {"decltype(auto)", &decltype_auto_identifier, cik_normal},
4229 {"initializer_list", &init_list_identifier, cik_normal},
4230 {"__for_range ", &for_range__identifier, cik_normal},
4231 {"__for_begin ", &for_begin__identifier, cik_normal},
4232 {"__for_end ", &for_end__identifier, cik_normal},
4233 {"__for_range", &for_range_identifier, cik_normal},
4234 {"__for_begin", &for_begin_identifier, cik_normal},
4235 {"__for_end", &for_end_identifier, cik_normal},
4236 {"abi_tag", &abi_tag_identifier, cik_normal},
4237 {"aligned", &aligned_identifier, cik_normal},
4238 {"begin", &begin_identifier, cik_normal},
4239 {"end", &end_identifier, cik_normal},
4240 {"get", &get__identifier, cik_normal},
4241 {"gnu", &gnu_identifier, cik_normal},
4242 {"tuple_element", &tuple_element_identifier, cik_normal},
4243 {"tuple_size", &tuple_size_identifier, cik_normal},
4244 {"type", &type_identifier, cik_normal},
4245 {"value", &value_identifier, cik_normal},
4246 {"_FUN", &fun_identifier, cik_normal},
4247 {"__closure", &closure_identifier, cik_normal},
4248 {"heap uninit", &heap_uninit_identifier, cik_normal},
4249 {"heap ", &heap_identifier, cik_normal},
4250 {"heap deleted", &heap_deleted_identifier, cik_normal},
4251 {NULL, NULL, cik_normal}
4252 };
4253
4254 for (const predefined_identifier *pid = predefined_identifiers;
4255 pid->name; ++pid)
4256 {
4257 *pid->node = get_identifier (pid->name);
4258 /* Some of these identifiers already have a special kind. */
4259 if (pid->kind != cik_normal)
4260 set_identifier_kind (*pid->node, pid->kind);
4261 }
4262 }
4263
4264 /* Create the predefined scalar types of C,
4265 and some nodes representing standard constants (0, 1, (void *)0).
4266 Initialize the global binding level.
4267 Make definitions for built-in primitive functions. */
4268
4269 void
cxx_init_decl_processing(void)4270 cxx_init_decl_processing (void)
4271 {
4272 tree void_ftype;
4273 tree void_ftype_ptr;
4274
4275 /* Create all the identifiers we need. */
4276 initialize_predefined_identifiers ();
4277
4278 /* Create the global variables. */
4279 push_to_top_level ();
4280
4281 current_function_decl = NULL_TREE;
4282 current_binding_level = NULL;
4283 /* Enter the global namespace. */
4284 gcc_assert (global_namespace == NULL_TREE);
4285 global_namespace = build_lang_decl (NAMESPACE_DECL, global_identifier,
4286 void_type_node);
4287 TREE_PUBLIC (global_namespace) = 1;
4288 DECL_CONTEXT (global_namespace)
4289 = build_translation_unit_decl (get_identifier (main_input_filename));
4290 /* Remember whether we want the empty class passing ABI change warning
4291 in this TU. */
4292 TRANSLATION_UNIT_WARN_EMPTY_P (DECL_CONTEXT (global_namespace))
4293 = warn_abi && abi_version_crosses (12);
4294 debug_hooks->register_main_translation_unit
4295 (DECL_CONTEXT (global_namespace));
4296 begin_scope (sk_namespace, global_namespace);
4297 current_namespace = global_namespace;
4298
4299 if (flag_visibility_ms_compat)
4300 default_visibility = VISIBILITY_HIDDEN;
4301
4302 /* Initially, C. */
4303 current_lang_name = lang_name_c;
4304
4305 /* Create the `std' namespace. */
4306 push_namespace (get_identifier ("std"));
4307 std_node = current_namespace;
4308 pop_namespace ();
4309
4310 flag_noexcept_type = (cxx_dialect >= cxx17);
4311
4312 c_common_nodes_and_builtins ();
4313
4314 tree bool_ftype = build_function_type_list (boolean_type_node, NULL_TREE);
4315 tree decl
4316 = add_builtin_function ("__builtin_is_constant_evaluated",
4317 bool_ftype, CP_BUILT_IN_IS_CONSTANT_EVALUATED,
4318 BUILT_IN_FRONTEND, NULL, NULL_TREE);
4319 set_call_expr_flags (decl, ECF_CONST | ECF_NOTHROW | ECF_LEAF);
4320
4321 tree cptr_ftype = build_function_type_list (const_ptr_type_node, NULL_TREE);
4322 decl = add_builtin_function ("__builtin_source_location",
4323 cptr_ftype, CP_BUILT_IN_SOURCE_LOCATION,
4324 BUILT_IN_FRONTEND, NULL, NULL_TREE);
4325 set_call_expr_flags (decl, ECF_CONST | ECF_NOTHROW | ECF_LEAF);
4326
4327 integer_two_node = build_int_cst (NULL_TREE, 2);
4328
4329 /* Guess at the initial static decls size. */
4330 vec_alloc (static_decls, 500);
4331
4332 /* ... and keyed classes. */
4333 vec_alloc (keyed_classes, 100);
4334
4335 record_builtin_type (RID_BOOL, "bool", boolean_type_node);
4336 truthvalue_type_node = boolean_type_node;
4337 truthvalue_false_node = boolean_false_node;
4338 truthvalue_true_node = boolean_true_node;
4339
4340 empty_except_spec = build_tree_list (NULL_TREE, NULL_TREE);
4341 noexcept_true_spec = build_tree_list (boolean_true_node, NULL_TREE);
4342 noexcept_false_spec = build_tree_list (boolean_false_node, NULL_TREE);
4343 noexcept_deferred_spec = build_tree_list (make_node (DEFERRED_NOEXCEPT),
4344 NULL_TREE);
4345
4346 #if 0
4347 record_builtin_type (RID_MAX, NULL, string_type_node);
4348 #endif
4349
4350 delta_type_node = ptrdiff_type_node;
4351 vtable_index_type = ptrdiff_type_node;
4352
4353 vtt_parm_type = build_pointer_type (const_ptr_type_node);
4354 void_ftype = build_function_type_list (void_type_node, NULL_TREE);
4355 void_ftype_ptr = build_function_type_list (void_type_node,
4356 ptr_type_node, NULL_TREE);
4357 void_ftype_ptr
4358 = build_exception_variant (void_ftype_ptr, empty_except_spec);
4359
4360 /* Create the conversion operator marker. This operator's DECL_NAME
4361 is in the identifier table, so we can use identifier equality to
4362 find it. */
4363 conv_op_marker = build_lang_decl (FUNCTION_DECL, conv_op_identifier,
4364 void_ftype);
4365
4366 /* C++ extensions */
4367
4368 unknown_type_node = make_node (LANG_TYPE);
4369 record_unknown_type (unknown_type_node, "unknown type");
4370
4371 /* Indirecting an UNKNOWN_TYPE node yields an UNKNOWN_TYPE node. */
4372 TREE_TYPE (unknown_type_node) = unknown_type_node;
4373
4374 /* Looking up TYPE_POINTER_TO and TYPE_REFERENCE_TO yield the same
4375 result. */
4376 TYPE_POINTER_TO (unknown_type_node) = unknown_type_node;
4377 TYPE_REFERENCE_TO (unknown_type_node) = unknown_type_node;
4378
4379 init_list_type_node = make_node (LANG_TYPE);
4380 record_unknown_type (init_list_type_node, "init list");
4381
4382 {
4383 /* Make sure we get a unique function type, so we can give
4384 its pointer type a name. (This wins for gdb.) */
4385 tree vfunc_type = make_node (FUNCTION_TYPE);
4386 TREE_TYPE (vfunc_type) = integer_type_node;
4387 TYPE_ARG_TYPES (vfunc_type) = NULL_TREE;
4388 layout_type (vfunc_type);
4389
4390 vtable_entry_type = build_pointer_type (vfunc_type);
4391 }
4392 record_builtin_type (RID_MAX, "__vtbl_ptr_type", vtable_entry_type);
4393
4394 vtbl_type_node
4395 = build_cplus_array_type (vtable_entry_type, NULL_TREE);
4396 layout_type (vtbl_type_node);
4397 vtbl_type_node = cp_build_qualified_type (vtbl_type_node, TYPE_QUAL_CONST);
4398 record_builtin_type (RID_MAX, NULL, vtbl_type_node);
4399 vtbl_ptr_type_node = build_pointer_type (vtable_entry_type);
4400 layout_type (vtbl_ptr_type_node);
4401 record_builtin_type (RID_MAX, NULL, vtbl_ptr_type_node);
4402
4403 push_namespace (get_identifier ("__cxxabiv1"));
4404 abi_node = current_namespace;
4405 pop_namespace ();
4406
4407 global_type_node = make_node (LANG_TYPE);
4408 record_unknown_type (global_type_node, "global type");
4409
4410 any_targ_node = make_node (LANG_TYPE);
4411 record_unknown_type (any_targ_node, "any type");
4412
4413 /* Now, C++. */
4414 current_lang_name = lang_name_cplusplus;
4415
4416 if (aligned_new_threshold > 1
4417 && !pow2p_hwi (aligned_new_threshold))
4418 {
4419 error ("%<-faligned-new=%d%> is not a power of two",
4420 aligned_new_threshold);
4421 aligned_new_threshold = 1;
4422 }
4423 if (aligned_new_threshold == -1)
4424 aligned_new_threshold = (cxx_dialect >= cxx17) ? 1 : 0;
4425 if (aligned_new_threshold == 1)
4426 aligned_new_threshold = malloc_alignment () / BITS_PER_UNIT;
4427
4428 {
4429 tree newattrs, extvisattr;
4430 tree newtype, deltype;
4431 tree ptr_ftype_sizetype;
4432 tree new_eh_spec;
4433
4434 ptr_ftype_sizetype
4435 = build_function_type_list (ptr_type_node, size_type_node, NULL_TREE);
4436 if (cxx_dialect == cxx98)
4437 {
4438 tree bad_alloc_id;
4439 tree bad_alloc_type_node;
4440 tree bad_alloc_decl;
4441
4442 push_nested_namespace (std_node);
4443 bad_alloc_id = get_identifier ("bad_alloc");
4444 bad_alloc_type_node = make_class_type (RECORD_TYPE);
4445 TYPE_CONTEXT (bad_alloc_type_node) = current_namespace;
4446 bad_alloc_decl
4447 = create_implicit_typedef (bad_alloc_id, bad_alloc_type_node);
4448 DECL_CONTEXT (bad_alloc_decl) = current_namespace;
4449 pop_nested_namespace (std_node);
4450
4451 new_eh_spec
4452 = add_exception_specifier (NULL_TREE, bad_alloc_type_node, -1);
4453 }
4454 else
4455 new_eh_spec = noexcept_false_spec;
4456
4457 /* Ensure attribs.c is initialized. */
4458 init_attributes ();
4459
4460 extvisattr = build_tree_list (get_identifier ("externally_visible"),
4461 NULL_TREE);
4462 newattrs = tree_cons (get_identifier ("alloc_size"),
4463 build_tree_list (NULL_TREE, integer_one_node),
4464 extvisattr);
4465 newtype = cp_build_type_attribute_variant (ptr_ftype_sizetype, newattrs);
4466 newtype = build_exception_variant (newtype, new_eh_spec);
4467 deltype = cp_build_type_attribute_variant (void_ftype_ptr, extvisattr);
4468 deltype = build_exception_variant (deltype, empty_except_spec);
4469 tree opnew = push_cp_library_fn (NEW_EXPR, newtype, 0);
4470 DECL_IS_MALLOC (opnew) = 1;
4471 DECL_SET_IS_OPERATOR_NEW (opnew, true);
4472 DECL_IS_REPLACEABLE_OPERATOR (opnew) = 1;
4473 opnew = push_cp_library_fn (VEC_NEW_EXPR, newtype, 0);
4474 DECL_IS_MALLOC (opnew) = 1;
4475 DECL_SET_IS_OPERATOR_NEW (opnew, true);
4476 DECL_IS_REPLACEABLE_OPERATOR (opnew) = 1;
4477 tree opdel = push_cp_library_fn (DELETE_EXPR, deltype, ECF_NOTHROW);
4478 DECL_SET_IS_OPERATOR_DELETE (opdel, true);
4479 DECL_IS_REPLACEABLE_OPERATOR (opdel) = 1;
4480 opdel = push_cp_library_fn (VEC_DELETE_EXPR, deltype, ECF_NOTHROW);
4481 DECL_SET_IS_OPERATOR_DELETE (opdel, true);
4482 DECL_IS_REPLACEABLE_OPERATOR (opdel) = 1;
4483 if (flag_sized_deallocation)
4484 {
4485 /* Also push the sized deallocation variants:
4486 void operator delete(void*, std::size_t) throw();
4487 void operator delete[](void*, std::size_t) throw(); */
4488 tree void_ftype_ptr_size
4489 = build_function_type_list (void_type_node, ptr_type_node,
4490 size_type_node, NULL_TREE);
4491 deltype = cp_build_type_attribute_variant (void_ftype_ptr_size,
4492 extvisattr);
4493 deltype = build_exception_variant (deltype, empty_except_spec);
4494 opdel = push_cp_library_fn (DELETE_EXPR, deltype, ECF_NOTHROW);
4495 DECL_SET_IS_OPERATOR_DELETE (opdel, true);
4496 DECL_IS_REPLACEABLE_OPERATOR (opdel) = 1;
4497 opdel = push_cp_library_fn (VEC_DELETE_EXPR, deltype, ECF_NOTHROW);
4498 DECL_SET_IS_OPERATOR_DELETE (opdel, true);
4499 DECL_IS_REPLACEABLE_OPERATOR (opdel) = 1;
4500 }
4501
4502 if (aligned_new_threshold)
4503 {
4504 push_nested_namespace (std_node);
4505 tree align_id = get_identifier ("align_val_t");
4506 align_type_node = start_enum (align_id, NULL_TREE, size_type_node,
4507 NULL_TREE, /*scoped*/true, NULL);
4508 pop_nested_namespace (std_node);
4509
4510 /* operator new (size_t, align_val_t); */
4511 newtype = build_function_type_list (ptr_type_node, size_type_node,
4512 align_type_node, NULL_TREE);
4513 newtype = cp_build_type_attribute_variant (newtype, newattrs);
4514 newtype = build_exception_variant (newtype, new_eh_spec);
4515 opnew = push_cp_library_fn (NEW_EXPR, newtype, 0);
4516 DECL_IS_MALLOC (opnew) = 1;
4517 DECL_SET_IS_OPERATOR_NEW (opnew, true);
4518 DECL_IS_REPLACEABLE_OPERATOR (opnew) = 1;
4519 opnew = push_cp_library_fn (VEC_NEW_EXPR, newtype, 0);
4520 DECL_IS_MALLOC (opnew) = 1;
4521 DECL_SET_IS_OPERATOR_NEW (opnew, true);
4522 DECL_IS_REPLACEABLE_OPERATOR (opnew) = 1;
4523
4524 /* operator delete (void *, align_val_t); */
4525 deltype = build_function_type_list (void_type_node, ptr_type_node,
4526 align_type_node, NULL_TREE);
4527 deltype = cp_build_type_attribute_variant (deltype, extvisattr);
4528 deltype = build_exception_variant (deltype, empty_except_spec);
4529 opdel = push_cp_library_fn (DELETE_EXPR, deltype, ECF_NOTHROW);
4530 DECL_SET_IS_OPERATOR_DELETE (opdel, true);
4531 DECL_IS_REPLACEABLE_OPERATOR (opdel) = 1;
4532 opdel = push_cp_library_fn (VEC_DELETE_EXPR, deltype, ECF_NOTHROW);
4533 DECL_SET_IS_OPERATOR_DELETE (opdel, true);
4534 DECL_IS_REPLACEABLE_OPERATOR (opdel) = 1;
4535
4536 if (flag_sized_deallocation)
4537 {
4538 /* operator delete (void *, size_t, align_val_t); */
4539 deltype = build_function_type_list (void_type_node, ptr_type_node,
4540 size_type_node, align_type_node,
4541 NULL_TREE);
4542 deltype = cp_build_type_attribute_variant (deltype, extvisattr);
4543 deltype = build_exception_variant (deltype, empty_except_spec);
4544 opdel = push_cp_library_fn (DELETE_EXPR, deltype, ECF_NOTHROW);
4545 DECL_SET_IS_OPERATOR_DELETE (opdel, true);
4546 DECL_IS_REPLACEABLE_OPERATOR (opdel) = 1;
4547 opdel = push_cp_library_fn (VEC_DELETE_EXPR, deltype, ECF_NOTHROW);
4548 DECL_SET_IS_OPERATOR_DELETE (opdel, true);
4549 DECL_IS_REPLACEABLE_OPERATOR (opdel) = 1;
4550 }
4551 }
4552
4553 nullptr_type_node = make_node (NULLPTR_TYPE);
4554 TYPE_SIZE (nullptr_type_node) = bitsize_int (GET_MODE_BITSIZE (ptr_mode));
4555 TYPE_SIZE_UNIT (nullptr_type_node) = size_int (GET_MODE_SIZE (ptr_mode));
4556 TYPE_UNSIGNED (nullptr_type_node) = 1;
4557 TYPE_PRECISION (nullptr_type_node) = GET_MODE_BITSIZE (ptr_mode);
4558 if (abi_version_at_least (9))
4559 SET_TYPE_ALIGN (nullptr_type_node, GET_MODE_ALIGNMENT (ptr_mode));
4560 SET_TYPE_MODE (nullptr_type_node, ptr_mode);
4561 record_builtin_type (RID_MAX, "decltype(nullptr)", nullptr_type_node);
4562 nullptr_node = build_int_cst (nullptr_type_node, 0);
4563 }
4564
4565 abort_fndecl
4566 = build_library_fn_ptr ("__cxa_pure_virtual", void_ftype,
4567 ECF_NORETURN | ECF_NOTHROW | ECF_COLD);
4568
4569 /* Perform other language dependent initializations. */
4570 init_class_processing ();
4571 init_rtti_processing ();
4572 init_template_processing ();
4573
4574 if (flag_exceptions)
4575 init_exception_processing ();
4576
4577 if (! supports_one_only ())
4578 flag_weak = 0;
4579
4580 make_fname_decl = cp_make_fname_decl;
4581 start_fname_decls ();
4582
4583 /* Show we use EH for cleanups. */
4584 if (flag_exceptions)
4585 using_eh_for_cleanups ();
4586 }
4587
4588 /* Generate an initializer for a function naming variable from
4589 NAME. NAME may be NULL, to indicate a dependent name. TYPE_P is
4590 filled in with the type of the init. */
4591
4592 tree
cp_fname_init(const char * name,tree * type_p)4593 cp_fname_init (const char* name, tree *type_p)
4594 {
4595 tree domain = NULL_TREE;
4596 tree type;
4597 tree init = NULL_TREE;
4598 size_t length = 0;
4599
4600 if (name)
4601 {
4602 length = strlen (name);
4603 domain = build_index_type (size_int (length));
4604 init = build_string (length + 1, name);
4605 }
4606
4607 type = cp_build_qualified_type (char_type_node, TYPE_QUAL_CONST);
4608 type = build_cplus_array_type (type, domain);
4609
4610 *type_p = type;
4611
4612 if (init)
4613 TREE_TYPE (init) = type;
4614 else
4615 init = error_mark_node;
4616
4617 return init;
4618 }
4619
4620 /* Create the VAR_DECL for __FUNCTION__ etc. ID is the name to give
4621 the decl, LOC is the location to give the decl, NAME is the
4622 initialization string and TYPE_DEP indicates whether NAME depended
4623 on the type of the function. We make use of that to detect
4624 __PRETTY_FUNCTION__ inside a template fn. This is being done lazily
4625 at the point of first use, so we mustn't push the decl now. */
4626
4627 static tree
cp_make_fname_decl(location_t loc,tree id,int type_dep)4628 cp_make_fname_decl (location_t loc, tree id, int type_dep)
4629 {
4630 const char * name = NULL;
4631 bool release_name = false;
4632 if (!(type_dep && in_template_function ()))
4633 {
4634 if (current_function_decl == NULL_TREE)
4635 name = "top level";
4636 else if (type_dep == 1) /* __PRETTY_FUNCTION__ */
4637 name = cxx_printable_name (current_function_decl, 2);
4638 else if (type_dep == 0) /* __FUNCTION__ */
4639 {
4640 name = fname_as_string (type_dep);
4641 release_name = true;
4642 }
4643 else
4644 gcc_unreachable ();
4645 }
4646 tree type;
4647 tree init = cp_fname_init (name, &type);
4648 tree decl = build_decl (loc, VAR_DECL, id, type);
4649
4650 if (release_name)
4651 free (CONST_CAST (char *, name));
4652
4653 /* As we're using pushdecl_with_scope, we must set the context. */
4654 DECL_CONTEXT (decl) = current_function_decl;
4655
4656 TREE_READONLY (decl) = 1;
4657 DECL_ARTIFICIAL (decl) = 1;
4658 DECL_DECLARED_CONSTEXPR_P (decl) = 1;
4659 TREE_STATIC (decl) = 1;
4660
4661 TREE_USED (decl) = 1;
4662
4663 if (init)
4664 {
4665 SET_DECL_VALUE_EXPR (decl, init);
4666 DECL_HAS_VALUE_EXPR_P (decl) = 1;
4667 /* For decl_constant_var_p. */
4668 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl) = 1;
4669 }
4670
4671 if (current_function_decl)
4672 {
4673 DECL_CONTEXT (decl) = current_function_decl;
4674 decl = pushdecl_outermost_localscope (decl);
4675 if (decl != error_mark_node)
4676 add_decl_expr (decl);
4677 }
4678 else
4679 {
4680 DECL_THIS_STATIC (decl) = true;
4681 pushdecl_top_level_and_finish (decl, NULL_TREE);
4682 }
4683
4684 return decl;
4685 }
4686
4687 /* Install DECL as a builtin function at current (global) scope.
4688 Return the new decl (if we found an existing version). Also
4689 installs it into ::std, if it's not '_*'. */
4690
4691 tree
cxx_builtin_function(tree decl)4692 cxx_builtin_function (tree decl)
4693 {
4694 retrofit_lang_decl (decl);
4695
4696 DECL_ARTIFICIAL (decl) = 1;
4697 SET_DECL_LANGUAGE (decl, lang_c);
4698 /* Runtime library routines are, by definition, available in an
4699 external shared object. */
4700 DECL_VISIBILITY (decl) = VISIBILITY_DEFAULT;
4701 DECL_VISIBILITY_SPECIFIED (decl) = 1;
4702
4703 tree id = DECL_NAME (decl);
4704 const char *name = IDENTIFIER_POINTER (id);
4705 if (name[0] != '_' || name[1] != '_')
4706 /* In the user's namespace, it must be declared before use. */
4707 DECL_ANTICIPATED (decl) = 1;
4708 else if (IDENTIFIER_LENGTH (id) > strlen ("___chk")
4709 && 0 != strncmp (name + 2, "builtin_", strlen ("builtin_"))
4710 && 0 == memcmp (name + IDENTIFIER_LENGTH (id) - strlen ("_chk"),
4711 "_chk", strlen ("_chk") + 1))
4712 /* Treat __*_chk fortification functions as anticipated as well,
4713 unless they are __builtin_*_chk. */
4714 DECL_ANTICIPATED (decl) = 1;
4715
4716 /* All builtins that don't begin with an '_' should additionally
4717 go in the 'std' namespace. */
4718 if (name[0] != '_')
4719 {
4720 tree std_decl = copy_decl (decl);
4721
4722 push_nested_namespace (std_node);
4723 DECL_CONTEXT (std_decl) = FROB_CONTEXT (std_node);
4724 pushdecl (std_decl);
4725 pop_nested_namespace (std_node);
4726 }
4727
4728 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4729 decl = pushdecl (decl);
4730
4731 return decl;
4732 }
4733
4734 /* Like cxx_builtin_function, but guarantee the function is added to the global
4735 scope. This is to allow function specific options to add new machine
4736 dependent builtins when the target ISA changes via attribute((target(...)))
4737 which saves space on program startup if the program does not use non-generic
4738 ISAs. */
4739
4740 tree
cxx_builtin_function_ext_scope(tree decl)4741 cxx_builtin_function_ext_scope (tree decl)
4742 {
4743 push_nested_namespace (global_namespace);
4744 decl = cxx_builtin_function (decl);
4745 pop_nested_namespace (global_namespace);
4746
4747 return decl;
4748 }
4749
4750 /* Implement LANG_HOOKS_SIMULATE_BUILTIN_FUNCTION_DECL. */
4751
4752 tree
cxx_simulate_builtin_function_decl(tree decl)4753 cxx_simulate_builtin_function_decl (tree decl)
4754 {
4755 retrofit_lang_decl (decl);
4756
4757 DECL_ARTIFICIAL (decl) = 1;
4758 SET_DECL_LANGUAGE (decl, lang_cplusplus);
4759 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
4760 return pushdecl (decl);
4761 }
4762
4763 /* Generate a FUNCTION_DECL with the typical flags for a runtime library
4764 function. Not called directly. */
4765
4766 static tree
build_library_fn(tree name,enum tree_code operator_code,tree type,int ecf_flags)4767 build_library_fn (tree name, enum tree_code operator_code, tree type,
4768 int ecf_flags)
4769 {
4770 tree fn = build_lang_decl (FUNCTION_DECL, name, type);
4771 DECL_EXTERNAL (fn) = 1;
4772 TREE_PUBLIC (fn) = 1;
4773 DECL_ARTIFICIAL (fn) = 1;
4774 DECL_OVERLOADED_OPERATOR_CODE_RAW (fn)
4775 = OVL_OP_INFO (false, operator_code)->ovl_op_code;
4776 SET_DECL_LANGUAGE (fn, lang_c);
4777 /* Runtime library routines are, by definition, available in an
4778 external shared object. */
4779 DECL_VISIBILITY (fn) = VISIBILITY_DEFAULT;
4780 DECL_VISIBILITY_SPECIFIED (fn) = 1;
4781 set_call_expr_flags (fn, ecf_flags);
4782 return fn;
4783 }
4784
4785 /* Returns the _DECL for a library function with C++ linkage. */
4786
4787 static tree
build_cp_library_fn(tree name,enum tree_code operator_code,tree type,int ecf_flags)4788 build_cp_library_fn (tree name, enum tree_code operator_code, tree type,
4789 int ecf_flags)
4790 {
4791 tree fn = build_library_fn (name, operator_code, type, ecf_flags);
4792 DECL_CONTEXT (fn) = FROB_CONTEXT (current_namespace);
4793 SET_DECL_LANGUAGE (fn, lang_cplusplus);
4794 return fn;
4795 }
4796
4797 /* Like build_library_fn, but takes a C string instead of an
4798 IDENTIFIER_NODE. */
4799
4800 tree
build_library_fn_ptr(const char * name,tree type,int ecf_flags)4801 build_library_fn_ptr (const char* name, tree type, int ecf_flags)
4802 {
4803 return build_library_fn (get_identifier (name), ERROR_MARK, type, ecf_flags);
4804 }
4805
4806 /* Like build_cp_library_fn, but takes a C string instead of an
4807 IDENTIFIER_NODE. */
4808
4809 tree
build_cp_library_fn_ptr(const char * name,tree type,int ecf_flags)4810 build_cp_library_fn_ptr (const char* name, tree type, int ecf_flags)
4811 {
4812 return build_cp_library_fn (get_identifier (name), ERROR_MARK, type,
4813 ecf_flags);
4814 }
4815
4816 /* Like build_library_fn, but also pushes the function so that we will
4817 be able to find it via get_global_binding. Also, the function
4818 may throw exceptions listed in RAISES. */
4819
4820 tree
push_library_fn(tree name,tree type,tree raises,int ecf_flags)4821 push_library_fn (tree name, tree type, tree raises, int ecf_flags)
4822 {
4823 tree fn;
4824
4825 if (raises)
4826 type = build_exception_variant (type, raises);
4827
4828 fn = build_library_fn (name, ERROR_MARK, type, ecf_flags);
4829 pushdecl_top_level (fn);
4830 return fn;
4831 }
4832
4833 /* Like build_cp_library_fn, but also pushes the function so that it
4834 will be found by normal lookup. */
4835
4836 static tree
push_cp_library_fn(enum tree_code operator_code,tree type,int ecf_flags)4837 push_cp_library_fn (enum tree_code operator_code, tree type,
4838 int ecf_flags)
4839 {
4840 tree fn = build_cp_library_fn (ovl_op_identifier (false, operator_code),
4841 operator_code, type, ecf_flags);
4842 pushdecl (fn);
4843 if (flag_tm)
4844 apply_tm_attr (fn, get_identifier ("transaction_safe"));
4845 return fn;
4846 }
4847
4848 /* Like push_library_fn, but takes a TREE_LIST of parm types rather than
4849 a FUNCTION_TYPE. */
4850
4851 tree
push_void_library_fn(tree name,tree parmtypes,int ecf_flags)4852 push_void_library_fn (tree name, tree parmtypes, int ecf_flags)
4853 {
4854 tree type = build_function_type (void_type_node, parmtypes);
4855 return push_library_fn (name, type, NULL_TREE, ecf_flags);
4856 }
4857
4858 /* Like push_library_fn, but also note that this function throws
4859 and does not return. Used for __throw_foo and the like. */
4860
4861 tree
push_throw_library_fn(tree name,tree type)4862 push_throw_library_fn (tree name, tree type)
4863 {
4864 tree fn = push_library_fn (name, type, NULL_TREE, ECF_NORETURN | ECF_COLD);
4865 return fn;
4866 }
4867
4868 /* When we call finish_struct for an anonymous union, we create
4869 default copy constructors and such. But, an anonymous union
4870 shouldn't have such things; this function undoes the damage to the
4871 anonymous union type T.
4872
4873 (The reason that we create the synthesized methods is that we don't
4874 distinguish `union { int i; }' from `typedef union { int i; } U'.
4875 The first is an anonymous union; the second is just an ordinary
4876 union type.) */
4877
4878 void
fixup_anonymous_aggr(tree t)4879 fixup_anonymous_aggr (tree t)
4880 {
4881 /* Wipe out memory of synthesized methods. */
4882 TYPE_HAS_USER_CONSTRUCTOR (t) = 0;
4883 TYPE_HAS_DEFAULT_CONSTRUCTOR (t) = 0;
4884 TYPE_HAS_COPY_CTOR (t) = 0;
4885 TYPE_HAS_CONST_COPY_CTOR (t) = 0;
4886 TYPE_HAS_COPY_ASSIGN (t) = 0;
4887 TYPE_HAS_CONST_COPY_ASSIGN (t) = 0;
4888
4889 /* Splice the implicitly generated functions out of TYPE_FIELDS. */
4890 for (tree probe, *prev_p = &TYPE_FIELDS (t); (probe = *prev_p);)
4891 if (TREE_CODE (probe) == FUNCTION_DECL && DECL_ARTIFICIAL (probe))
4892 *prev_p = DECL_CHAIN (probe);
4893 else
4894 prev_p = &DECL_CHAIN (probe);
4895
4896 /* Anonymous aggregates cannot have fields with ctors, dtors or complex
4897 assignment operators (because they cannot have these methods themselves).
4898 For anonymous unions this is already checked because they are not allowed
4899 in any union, otherwise we have to check it. */
4900 if (TREE_CODE (t) != UNION_TYPE)
4901 {
4902 tree field, type;
4903
4904 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
4905 if (TREE_CODE (field) == FIELD_DECL)
4906 {
4907 type = TREE_TYPE (field);
4908 if (CLASS_TYPE_P (type))
4909 {
4910 if (TYPE_NEEDS_CONSTRUCTING (type))
4911 error ("member %q+#D with constructor not allowed "
4912 "in anonymous aggregate", field);
4913 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
4914 error ("member %q+#D with destructor not allowed "
4915 "in anonymous aggregate", field);
4916 if (TYPE_HAS_COMPLEX_COPY_ASSIGN (type))
4917 error ("member %q+#D with copy assignment operator "
4918 "not allowed in anonymous aggregate", field);
4919 }
4920 }
4921 }
4922 }
4923
4924 /* Warn for an attribute located at LOCATION that appertains to the
4925 class type CLASS_TYPE that has not been properly placed after its
4926 class-key, in it class-specifier. */
4927
4928 void
warn_misplaced_attr_for_class_type(location_t location,tree class_type)4929 warn_misplaced_attr_for_class_type (location_t location,
4930 tree class_type)
4931 {
4932 gcc_assert (OVERLOAD_TYPE_P (class_type));
4933
4934 auto_diagnostic_group d;
4935 if (warning_at (location, OPT_Wattributes,
4936 "attribute ignored in declaration "
4937 "of %q#T", class_type))
4938 inform (location,
4939 "attribute for %q#T must follow the %qs keyword",
4940 class_type, class_key_or_enum_as_string (class_type));
4941 }
4942
4943 /* Returns the cv-qualifiers that apply to the type specified
4944 by the DECLSPECS. */
4945
4946 static int
get_type_quals(const cp_decl_specifier_seq * declspecs)4947 get_type_quals (const cp_decl_specifier_seq *declspecs)
4948 {
4949 int type_quals = TYPE_UNQUALIFIED;
4950
4951 if (decl_spec_seq_has_spec_p (declspecs, ds_const))
4952 type_quals |= TYPE_QUAL_CONST;
4953 if (decl_spec_seq_has_spec_p (declspecs, ds_volatile))
4954 type_quals |= TYPE_QUAL_VOLATILE;
4955 if (decl_spec_seq_has_spec_p (declspecs, ds_restrict))
4956 type_quals |= TYPE_QUAL_RESTRICT;
4957
4958 return type_quals;
4959 }
4960
4961 /* Make sure that a declaration with no declarator is well-formed, i.e.
4962 just declares a tagged type or anonymous union.
4963
4964 Returns the type declared; or NULL_TREE if none. */
4965
4966 tree
check_tag_decl(cp_decl_specifier_seq * declspecs,bool explicit_type_instantiation_p)4967 check_tag_decl (cp_decl_specifier_seq *declspecs,
4968 bool explicit_type_instantiation_p)
4969 {
4970 int saw_friend = decl_spec_seq_has_spec_p (declspecs, ds_friend);
4971 int saw_typedef = decl_spec_seq_has_spec_p (declspecs, ds_typedef);
4972 /* If a class, struct, or enum type is declared by the DECLSPECS
4973 (i.e, if a class-specifier, enum-specifier, or non-typename
4974 elaborated-type-specifier appears in the DECLSPECS),
4975 DECLARED_TYPE is set to the corresponding type. */
4976 tree declared_type = NULL_TREE;
4977 bool error_p = false;
4978
4979 if (declspecs->multiple_types_p)
4980 error_at (smallest_type_location (declspecs),
4981 "multiple types in one declaration");
4982 else if (declspecs->redefined_builtin_type)
4983 {
4984 location_t loc = declspecs->locations[ds_redefined_builtin_type_spec];
4985 if (!in_system_header_at (loc))
4986 permerror (loc, "redeclaration of C++ built-in type %qT",
4987 declspecs->redefined_builtin_type);
4988 return NULL_TREE;
4989 }
4990
4991 if (declspecs->type
4992 && TYPE_P (declspecs->type)
4993 && ((TREE_CODE (declspecs->type) != TYPENAME_TYPE
4994 && MAYBE_CLASS_TYPE_P (declspecs->type))
4995 || TREE_CODE (declspecs->type) == ENUMERAL_TYPE))
4996 declared_type = declspecs->type;
4997 else if (declspecs->type == error_mark_node)
4998 error_p = true;
4999
5000 if (type_uses_auto (declared_type))
5001 {
5002 error_at (declspecs->locations[ds_type_spec],
5003 "%<auto%> can only be specified for variables "
5004 "or function declarations");
5005 return error_mark_node;
5006 }
5007
5008 if (declared_type && !OVERLOAD_TYPE_P (declared_type))
5009 declared_type = NULL_TREE;
5010
5011 if (!declared_type && !saw_friend && !error_p)
5012 permerror (input_location, "declaration does not declare anything");
5013 /* Check for an anonymous union. */
5014 else if (declared_type && RECORD_OR_UNION_CODE_P (TREE_CODE (declared_type))
5015 && TYPE_UNNAMED_P (declared_type))
5016 {
5017 /* 7/3 In a simple-declaration, the optional init-declarator-list
5018 can be omitted only when declaring a class (clause 9) or
5019 enumeration (7.2), that is, when the decl-specifier-seq contains
5020 either a class-specifier, an elaborated-type-specifier with
5021 a class-key (9.1), or an enum-specifier. In these cases and
5022 whenever a class-specifier or enum-specifier is present in the
5023 decl-specifier-seq, the identifiers in these specifiers are among
5024 the names being declared by the declaration (as class-name,
5025 enum-names, or enumerators, depending on the syntax). In such
5026 cases, and except for the declaration of an unnamed bit-field (9.6),
5027 the decl-specifier-seq shall introduce one or more names into the
5028 program, or shall redeclare a name introduced by a previous
5029 declaration. [Example:
5030 enum { }; // ill-formed
5031 typedef class { }; // ill-formed
5032 --end example] */
5033 if (saw_typedef)
5034 {
5035 error_at (declspecs->locations[ds_typedef],
5036 "missing type-name in typedef-declaration");
5037 return NULL_TREE;
5038 }
5039 /* Anonymous unions are objects, so they can have specifiers. */;
5040 SET_ANON_AGGR_TYPE_P (declared_type);
5041
5042 if (TREE_CODE (declared_type) != UNION_TYPE)
5043 pedwarn (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (declared_type)),
5044 OPT_Wpedantic, "ISO C++ prohibits anonymous structs");
5045 }
5046
5047 else
5048 {
5049 if (decl_spec_seq_has_spec_p (declspecs, ds_inline))
5050 error_at (declspecs->locations[ds_inline],
5051 "%<inline%> can only be specified for functions");
5052 else if (decl_spec_seq_has_spec_p (declspecs, ds_virtual))
5053 error_at (declspecs->locations[ds_virtual],
5054 "%<virtual%> can only be specified for functions");
5055 else if (saw_friend
5056 && (!current_class_type
5057 || current_scope () != current_class_type))
5058 error_at (declspecs->locations[ds_friend],
5059 "%<friend%> can only be specified inside a class");
5060 else if (decl_spec_seq_has_spec_p (declspecs, ds_explicit))
5061 error_at (declspecs->locations[ds_explicit],
5062 "%<explicit%> can only be specified for constructors");
5063 else if (declspecs->storage_class)
5064 error_at (declspecs->locations[ds_storage_class],
5065 "a storage class can only be specified for objects "
5066 "and functions");
5067 else if (decl_spec_seq_has_spec_p (declspecs, ds_const))
5068 error_at (declspecs->locations[ds_const],
5069 "%<const%> can only be specified for objects and "
5070 "functions");
5071 else if (decl_spec_seq_has_spec_p (declspecs, ds_volatile))
5072 error_at (declspecs->locations[ds_volatile],
5073 "%<volatile%> can only be specified for objects and "
5074 "functions");
5075 else if (decl_spec_seq_has_spec_p (declspecs, ds_restrict))
5076 error_at (declspecs->locations[ds_restrict],
5077 "%<__restrict%> can only be specified for objects and "
5078 "functions");
5079 else if (decl_spec_seq_has_spec_p (declspecs, ds_thread))
5080 error_at (declspecs->locations[ds_thread],
5081 "%<__thread%> can only be specified for objects "
5082 "and functions");
5083 else if (saw_typedef)
5084 warning_at (declspecs->locations[ds_typedef], 0,
5085 "%<typedef%> was ignored in this declaration");
5086 else if (decl_spec_seq_has_spec_p (declspecs, ds_constexpr))
5087 error_at (declspecs->locations[ds_constexpr],
5088 "%qs cannot be used for type declarations", "constexpr");
5089 else if (decl_spec_seq_has_spec_p (declspecs, ds_constinit))
5090 error_at (declspecs->locations[ds_constinit],
5091 "%qs cannot be used for type declarations", "constinit");
5092 else if (decl_spec_seq_has_spec_p (declspecs, ds_consteval))
5093 error_at (declspecs->locations[ds_consteval],
5094 "%qs cannot be used for type declarations", "consteval");
5095 }
5096
5097 if (declspecs->attributes && warn_attributes && declared_type)
5098 {
5099 location_t loc;
5100 if (!CLASS_TYPE_P (declared_type)
5101 || !CLASSTYPE_TEMPLATE_INSTANTIATION (declared_type))
5102 /* For a non-template class, use the name location. */
5103 loc = location_of (declared_type);
5104 else
5105 /* For a template class (an explicit instantiation), use the
5106 current location. */
5107 loc = input_location;
5108
5109 if (explicit_type_instantiation_p)
5110 /* [dcl.attr.grammar]/4:
5111
5112 No attribute-specifier-seq shall appertain to an explicit
5113 instantiation. */
5114 {
5115 if (warning_at (loc, OPT_Wattributes,
5116 "attribute ignored in explicit instantiation %q#T",
5117 declared_type))
5118 inform (loc,
5119 "no attribute can be applied to "
5120 "an explicit instantiation");
5121 }
5122 else
5123 warn_misplaced_attr_for_class_type (loc, declared_type);
5124 }
5125
5126 return declared_type;
5127 }
5128
5129 /* Called when a declaration is seen that contains no names to declare.
5130 If its type is a reference to a structure, union or enum inherited
5131 from a containing scope, shadow that tag name for the current scope
5132 with a forward reference.
5133 If its type defines a new named structure or union
5134 or defines an enum, it is valid but we need not do anything here.
5135 Otherwise, it is an error.
5136
5137 C++: may have to grok the declspecs to learn about static,
5138 complain for anonymous unions.
5139
5140 Returns the TYPE declared -- or NULL_TREE if none. */
5141
5142 tree
shadow_tag(cp_decl_specifier_seq * declspecs)5143 shadow_tag (cp_decl_specifier_seq *declspecs)
5144 {
5145 tree t = check_tag_decl (declspecs,
5146 /*explicit_type_instantiation_p=*/false);
5147
5148 if (!t)
5149 return NULL_TREE;
5150
5151 if (maybe_process_partial_specialization (t) == error_mark_node)
5152 return NULL_TREE;
5153
5154 /* This is where the variables in an anonymous union are
5155 declared. An anonymous union declaration looks like:
5156 union { ... } ;
5157 because there is no declarator after the union, the parser
5158 sends that declaration here. */
5159 if (ANON_AGGR_TYPE_P (t))
5160 {
5161 fixup_anonymous_aggr (t);
5162
5163 if (TYPE_FIELDS (t))
5164 {
5165 tree decl = grokdeclarator (/*declarator=*/NULL,
5166 declspecs, NORMAL, 0, NULL);
5167 finish_anon_union (decl);
5168 }
5169 }
5170
5171 return t;
5172 }
5173
5174 /* Decode a "typename", such as "int **", returning a ..._TYPE node. */
5175
5176 tree
groktypename(cp_decl_specifier_seq * type_specifiers,const cp_declarator * declarator,bool is_template_arg)5177 groktypename (cp_decl_specifier_seq *type_specifiers,
5178 const cp_declarator *declarator,
5179 bool is_template_arg)
5180 {
5181 tree attrs;
5182 tree type;
5183 enum decl_context context
5184 = is_template_arg ? TEMPLATE_TYPE_ARG : TYPENAME;
5185 attrs = type_specifiers->attributes;
5186 type_specifiers->attributes = NULL_TREE;
5187 type = grokdeclarator (declarator, type_specifiers, context, 0, &attrs);
5188 if (attrs && type != error_mark_node)
5189 {
5190 if (CLASS_TYPE_P (type))
5191 warning (OPT_Wattributes, "ignoring attributes applied to class type %qT "
5192 "outside of definition", type);
5193 else if (MAYBE_CLASS_TYPE_P (type))
5194 /* A template type parameter or other dependent type. */
5195 warning (OPT_Wattributes, "ignoring attributes applied to dependent "
5196 "type %qT without an associated declaration", type);
5197 else
5198 cplus_decl_attributes (&type, attrs, 0);
5199 }
5200 return type;
5201 }
5202
5203 /* Process a DECLARATOR for a function-scope variable declaration,
5204 namespace-scope variable declaration, or function declaration.
5205 (Function definitions go through start_function; class member
5206 declarations appearing in the body of the class go through
5207 grokfield.) The DECL corresponding to the DECLARATOR is returned.
5208 If an error occurs, the error_mark_node is returned instead.
5209
5210 DECLSPECS are the decl-specifiers for the declaration. INITIALIZED is
5211 SD_INITIALIZED if an explicit initializer is present, or SD_DEFAULTED
5212 for an explicitly defaulted function, or SD_DELETED for an explicitly
5213 deleted function, but 0 (SD_UNINITIALIZED) if this is a variable
5214 implicitly initialized via a default constructor. ATTRIBUTES and
5215 PREFIX_ATTRIBUTES are GNU attributes associated with this declaration.
5216
5217 The scope represented by the context of the returned DECL is pushed
5218 (if it is not the global namespace) and is assigned to
5219 *PUSHED_SCOPE_P. The caller is then responsible for calling
5220 pop_scope on *PUSHED_SCOPE_P if it is set. */
5221
5222 tree
start_decl(const cp_declarator * declarator,cp_decl_specifier_seq * declspecs,int initialized,tree attributes,tree prefix_attributes,tree * pushed_scope_p)5223 start_decl (const cp_declarator *declarator,
5224 cp_decl_specifier_seq *declspecs,
5225 int initialized,
5226 tree attributes,
5227 tree prefix_attributes,
5228 tree *pushed_scope_p)
5229 {
5230 tree decl;
5231 tree context;
5232 bool was_public;
5233 int flags;
5234 bool alias;
5235
5236 *pushed_scope_p = NULL_TREE;
5237
5238 /* An object declared as __attribute__((deprecated)) suppresses
5239 warnings of uses of other deprecated items. */
5240 if (lookup_attribute ("deprecated", attributes))
5241 deprecated_state = DEPRECATED_SUPPRESS;
5242
5243 attributes = chainon (attributes, prefix_attributes);
5244
5245 decl = grokdeclarator (declarator, declspecs, NORMAL, initialized,
5246 &attributes);
5247
5248 deprecated_state = DEPRECATED_NORMAL;
5249
5250 if (decl == NULL_TREE || VOID_TYPE_P (decl)
5251 || decl == error_mark_node)
5252 return error_mark_node;
5253
5254 context = CP_DECL_CONTEXT (decl);
5255 if (context != global_namespace)
5256 *pushed_scope_p = push_scope (context);
5257
5258 /* Is it valid for this decl to have an initializer at all?
5259 If not, set INITIALIZED to zero, which will indirectly
5260 tell `cp_finish_decl' to ignore the initializer once it is parsed. */
5261 if (initialized
5262 && TREE_CODE (decl) == TYPE_DECL)
5263 {
5264 error_at (DECL_SOURCE_LOCATION (decl),
5265 "typedef %qD is initialized (use %qs instead)",
5266 decl, "decltype");
5267 return error_mark_node;
5268 }
5269
5270 if (initialized)
5271 {
5272 if (! toplevel_bindings_p ()
5273 && DECL_EXTERNAL (decl))
5274 warning (0, "declaration of %q#D has %<extern%> and is initialized",
5275 decl);
5276 DECL_EXTERNAL (decl) = 0;
5277 if (toplevel_bindings_p ())
5278 TREE_STATIC (decl) = 1;
5279 }
5280 alias = lookup_attribute ("alias", DECL_ATTRIBUTES (decl)) != 0;
5281
5282 if (alias && TREE_CODE (decl) == FUNCTION_DECL)
5283 record_key_method_defined (decl);
5284
5285 /* If this is a typedef that names the class for linkage purposes
5286 (7.1.3p8), apply any attributes directly to the type. */
5287 if (TREE_CODE (decl) == TYPE_DECL
5288 && OVERLOAD_TYPE_P (TREE_TYPE (decl))
5289 && decl == TYPE_NAME (TYPE_MAIN_VARIANT (TREE_TYPE (decl))))
5290 flags = ATTR_FLAG_TYPE_IN_PLACE;
5291 else
5292 flags = 0;
5293
5294 /* Set attributes here so if duplicate decl, will have proper attributes. */
5295 cplus_decl_attributes (&decl, attributes, flags);
5296
5297 /* Dllimported symbols cannot be defined. Static data members (which
5298 can be initialized in-class and dllimported) go through grokfield,
5299 not here, so we don't need to exclude those decls when checking for
5300 a definition. */
5301 if (initialized && DECL_DLLIMPORT_P (decl))
5302 {
5303 error_at (DECL_SOURCE_LOCATION (decl),
5304 "definition of %q#D is marked %<dllimport%>", decl);
5305 DECL_DLLIMPORT_P (decl) = 0;
5306 }
5307
5308 /* If #pragma weak was used, mark the decl weak now. */
5309 if (!processing_template_decl && !DECL_DECOMPOSITION_P (decl))
5310 maybe_apply_pragma_weak (decl);
5311
5312 if (TREE_CODE (decl) == FUNCTION_DECL
5313 && DECL_DECLARED_INLINE_P (decl)
5314 && DECL_UNINLINABLE (decl)
5315 && lookup_attribute ("noinline", DECL_ATTRIBUTES (decl)))
5316 warning_at (DECL_SOURCE_LOCATION (decl), 0,
5317 "inline function %qD given attribute %qs", decl, "noinline");
5318
5319 if (TYPE_P (context) && COMPLETE_TYPE_P (complete_type (context)))
5320 {
5321 bool this_tmpl = (processing_template_decl
5322 > template_class_depth (context));
5323 if (VAR_P (decl))
5324 {
5325 tree field = lookup_field (context, DECL_NAME (decl), 0, false);
5326 if (field == NULL_TREE
5327 || !(VAR_P (field) || variable_template_p (field)))
5328 error ("%q+#D is not a static data member of %q#T", decl, context);
5329 else if (variable_template_p (field)
5330 && (DECL_LANG_SPECIFIC (decl)
5331 && DECL_TEMPLATE_SPECIALIZATION (decl)))
5332 /* OK, specialization was already checked. */;
5333 else if (variable_template_p (field) && !this_tmpl)
5334 {
5335 error_at (DECL_SOURCE_LOCATION (decl),
5336 "non-member-template declaration of %qD", decl);
5337 inform (DECL_SOURCE_LOCATION (field), "does not match "
5338 "member template declaration here");
5339 return error_mark_node;
5340 }
5341 else
5342 {
5343 if (variable_template_p (field))
5344 field = DECL_TEMPLATE_RESULT (field);
5345
5346 if (DECL_CONTEXT (field) != context)
5347 {
5348 if (!same_type_p (DECL_CONTEXT (field), context))
5349 permerror (input_location, "ISO C++ does not permit %<%T::%D%> "
5350 "to be defined as %<%T::%D%>",
5351 DECL_CONTEXT (field), DECL_NAME (decl),
5352 context, DECL_NAME (decl));
5353 DECL_CONTEXT (decl) = DECL_CONTEXT (field);
5354 }
5355 /* Static data member are tricky; an in-class initialization
5356 still doesn't provide a definition, so the in-class
5357 declaration will have DECL_EXTERNAL set, but will have an
5358 initialization. Thus, duplicate_decls won't warn
5359 about this situation, and so we check here. */
5360 if (initialized && DECL_INITIALIZED_IN_CLASS_P (field))
5361 error ("duplicate initialization of %qD", decl);
5362 field = duplicate_decls (decl, field,
5363 /*newdecl_is_friend=*/false);
5364 if (field == error_mark_node)
5365 return error_mark_node;
5366 else if (field)
5367 decl = field;
5368 }
5369 }
5370 else
5371 {
5372 tree field = check_classfn (context, decl,
5373 this_tmpl
5374 ? current_template_parms
5375 : NULL_TREE);
5376 if (field && field != error_mark_node
5377 && duplicate_decls (decl, field,
5378 /*newdecl_is_friend=*/false))
5379 decl = field;
5380 }
5381
5382 /* cp_finish_decl sets DECL_EXTERNAL if DECL_IN_AGGR_P is set. */
5383 DECL_IN_AGGR_P (decl) = 0;
5384 /* Do not mark DECL as an explicit specialization if it was not
5385 already marked as an instantiation; a declaration should
5386 never be marked as a specialization unless we know what
5387 template is being specialized. */
5388 if (DECL_LANG_SPECIFIC (decl) && DECL_USE_TEMPLATE (decl))
5389 {
5390 SET_DECL_TEMPLATE_SPECIALIZATION (decl);
5391 if (TREE_CODE (decl) == FUNCTION_DECL)
5392 DECL_COMDAT (decl) = (TREE_PUBLIC (decl)
5393 && DECL_DECLARED_INLINE_P (decl));
5394 else
5395 DECL_COMDAT (decl) = false;
5396
5397 /* [temp.expl.spec] An explicit specialization of a static data
5398 member of a template is a definition if the declaration
5399 includes an initializer; otherwise, it is a declaration.
5400
5401 We check for processing_specialization so this only applies
5402 to the new specialization syntax. */
5403 if (!initialized && processing_specialization)
5404 DECL_EXTERNAL (decl) = 1;
5405 }
5406
5407 if (DECL_EXTERNAL (decl) && ! DECL_TEMPLATE_SPECIALIZATION (decl)
5408 /* Aliases are definitions. */
5409 && !alias)
5410 permerror (declarator->id_loc,
5411 "declaration of %q#D outside of class is not definition",
5412 decl);
5413 }
5414
5415 was_public = TREE_PUBLIC (decl);
5416
5417 /* Enter this declaration into the symbol table. Don't push the plain
5418 VAR_DECL for a variable template. */
5419 if (!template_parm_scope_p ()
5420 || !VAR_P (decl))
5421 decl = maybe_push_decl (decl);
5422
5423 if (processing_template_decl)
5424 {
5425 /* Make sure that for a `constinit' decl push_template_decl creates
5426 a DECL_TEMPLATE_INFO info for us, so that cp_finish_decl can then set
5427 TINFO_VAR_DECLARED_CONSTINIT. */
5428 if (decl_spec_seq_has_spec_p (declspecs, ds_constinit))
5429 retrofit_lang_decl (decl);
5430 decl = push_template_decl (decl);
5431 }
5432 if (decl == error_mark_node)
5433 return error_mark_node;
5434
5435 if (VAR_P (decl)
5436 && DECL_NAMESPACE_SCOPE_P (decl) && !TREE_PUBLIC (decl) && !was_public
5437 && !DECL_THIS_STATIC (decl) && !DECL_ARTIFICIAL (decl))
5438 {
5439 /* This is a const variable with implicit 'static'. Set
5440 DECL_THIS_STATIC so we can tell it from variables that are
5441 !TREE_PUBLIC because of the anonymous namespace. */
5442 gcc_assert (CP_TYPE_CONST_P (TREE_TYPE (decl)) || errorcount);
5443 DECL_THIS_STATIC (decl) = 1;
5444 }
5445
5446 if (current_function_decl && VAR_P (decl)
5447 && DECL_DECLARED_CONSTEXPR_P (current_function_decl))
5448 {
5449 bool ok = false;
5450 if (CP_DECL_THREAD_LOCAL_P (decl))
5451 error_at (DECL_SOURCE_LOCATION (decl),
5452 "%qD declared %<thread_local%> in %qs function", decl,
5453 DECL_IMMEDIATE_FUNCTION_P (current_function_decl)
5454 ? "consteval" : "constexpr");
5455 else if (TREE_STATIC (decl))
5456 error_at (DECL_SOURCE_LOCATION (decl),
5457 "%qD declared %<static%> in %qs function", decl,
5458 DECL_IMMEDIATE_FUNCTION_P (current_function_decl)
5459 ? "consteval" : "constexpr");
5460 else
5461 ok = true;
5462 if (!ok)
5463 cp_function_chain->invalid_constexpr = true;
5464 }
5465
5466 if (!processing_template_decl && VAR_P (decl))
5467 start_decl_1 (decl, initialized);
5468
5469 return decl;
5470 }
5471
5472 /* Process the declaration of a variable DECL. INITIALIZED is true
5473 iff DECL is explicitly initialized. (INITIALIZED is false if the
5474 variable is initialized via an implicitly-called constructor.)
5475 This function must be called for ordinary variables (including, for
5476 example, implicit instantiations of templates), but must not be
5477 called for template declarations. */
5478
5479 void
start_decl_1(tree decl,bool initialized)5480 start_decl_1 (tree decl, bool initialized)
5481 {
5482 tree type;
5483 bool complete_p;
5484 bool aggregate_definition_p;
5485
5486 gcc_assert (!processing_template_decl);
5487
5488 if (error_operand_p (decl))
5489 return;
5490
5491 gcc_assert (VAR_P (decl));
5492
5493 type = TREE_TYPE (decl);
5494 complete_p = COMPLETE_TYPE_P (type);
5495 aggregate_definition_p = MAYBE_CLASS_TYPE_P (type) && !DECL_EXTERNAL (decl);
5496
5497 /* If an explicit initializer is present, or if this is a definition
5498 of an aggregate, then we need a complete type at this point.
5499 (Scalars are always complete types, so there is nothing to
5500 check.) This code just sets COMPLETE_P; errors (if necessary)
5501 are issued below. */
5502 if ((initialized || aggregate_definition_p)
5503 && !complete_p
5504 && COMPLETE_TYPE_P (complete_type (type)))
5505 {
5506 complete_p = true;
5507 /* We will not yet have set TREE_READONLY on DECL if the type
5508 was "const", but incomplete, before this point. But, now, we
5509 have a complete type, so we can try again. */
5510 cp_apply_type_quals_to_decl (cp_type_quals (type), decl);
5511 }
5512
5513 if (is_global_var (decl))
5514 {
5515 type_context_kind context = (DECL_THREAD_LOCAL_P (decl)
5516 ? TCTX_THREAD_STORAGE
5517 : TCTX_STATIC_STORAGE);
5518 verify_type_context (input_location, context, TREE_TYPE (decl));
5519 }
5520 if (initialized)
5521 /* Is it valid for this decl to have an initializer at all? */
5522 {
5523 /* Don't allow initializations for incomplete types except for
5524 arrays which might be completed by the initialization. */
5525 if (complete_p)
5526 ; /* A complete type is ok. */
5527 else if (type_uses_auto (type))
5528 ; /* An auto type is ok. */
5529 else if (TREE_CODE (type) != ARRAY_TYPE)
5530 {
5531 error ("variable %q#D has initializer but incomplete type", decl);
5532 type = TREE_TYPE (decl) = error_mark_node;
5533 }
5534 else if (!COMPLETE_TYPE_P (complete_type (TREE_TYPE (type))))
5535 {
5536 if (DECL_LANG_SPECIFIC (decl) && DECL_TEMPLATE_INFO (decl))
5537 error ("elements of array %q#D have incomplete type", decl);
5538 /* else we already gave an error in start_decl. */
5539 }
5540 }
5541 else if (aggregate_definition_p && !complete_p)
5542 {
5543 if (type_uses_auto (type))
5544 gcc_assert (CLASS_PLACEHOLDER_TEMPLATE (type));
5545 else
5546 {
5547 error ("aggregate %q#D has incomplete type and cannot be defined",
5548 decl);
5549 /* Change the type so that assemble_variable will give
5550 DECL an rtl we can live with: (mem (const_int 0)). */
5551 type = TREE_TYPE (decl) = error_mark_node;
5552 }
5553 }
5554
5555 /* Create a new scope to hold this declaration if necessary.
5556 Whether or not a new scope is necessary cannot be determined
5557 until after the type has been completed; if the type is a
5558 specialization of a class template it is not until after
5559 instantiation has occurred that TYPE_HAS_NONTRIVIAL_DESTRUCTOR
5560 will be set correctly. */
5561 maybe_push_cleanup_level (type);
5562 }
5563
5564 /* Handle initialization of references. DECL, TYPE, and INIT have the
5565 same meaning as in cp_finish_decl. *CLEANUP must be NULL on entry,
5566 but will be set to a new CLEANUP_STMT if a temporary is created
5567 that must be destroyed subsequently.
5568
5569 Returns an initializer expression to use to initialize DECL, or
5570 NULL if the initialization can be performed statically.
5571
5572 Quotes on semantics can be found in ARM 8.4.3. */
5573
5574 static tree
grok_reference_init(tree decl,tree type,tree init,int flags)5575 grok_reference_init (tree decl, tree type, tree init, int flags)
5576 {
5577 if (init == NULL_TREE)
5578 {
5579 if ((DECL_LANG_SPECIFIC (decl) == 0
5580 || DECL_IN_AGGR_P (decl) == 0)
5581 && ! DECL_THIS_EXTERN (decl))
5582 error_at (DECL_SOURCE_LOCATION (decl),
5583 "%qD declared as reference but not initialized", decl);
5584 return NULL_TREE;
5585 }
5586
5587 tree ttype = TREE_TYPE (type);
5588 if (TREE_CODE (init) == TREE_LIST)
5589 {
5590 /* This handles (C++20 only) code like
5591
5592 const A& r(1, 2, 3);
5593
5594 where we treat the parenthesized list as a CONSTRUCTOR. */
5595 if (TREE_TYPE (init) == NULL_TREE
5596 && CP_AGGREGATE_TYPE_P (ttype)
5597 && !DECL_DECOMPOSITION_P (decl)
5598 && (cxx_dialect >= cxx2a))
5599 {
5600 /* We don't know yet if we should treat const A& r(1) as
5601 const A& r{1}. */
5602 if (list_length (init) == 1)
5603 {
5604 flags |= LOOKUP_AGGREGATE_PAREN_INIT;
5605 init = build_x_compound_expr_from_list (init, ELK_INIT,
5606 tf_warning_or_error);
5607 }
5608 /* If the list had more than one element, the code is ill-formed
5609 pre-C++20, so we can build a constructor right away. */
5610 else
5611 {
5612 init = build_constructor_from_list (init_list_type_node, init);
5613 CONSTRUCTOR_IS_DIRECT_INIT (init) = true;
5614 CONSTRUCTOR_IS_PAREN_INIT (init) = true;
5615 }
5616 }
5617 else
5618 init = build_x_compound_expr_from_list (init, ELK_INIT,
5619 tf_warning_or_error);
5620 }
5621
5622 if (TREE_CODE (ttype) != ARRAY_TYPE
5623 && TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE)
5624 /* Note: default conversion is only called in very special cases. */
5625 init = decay_conversion (init, tf_warning_or_error);
5626
5627 /* check_initializer handles this for non-reference variables, but for
5628 references we need to do it here or the initializer will get the
5629 incomplete array type and confuse later calls to
5630 cp_complete_array_type. */
5631 if (TREE_CODE (ttype) == ARRAY_TYPE
5632 && TYPE_DOMAIN (ttype) == NULL_TREE
5633 && (BRACE_ENCLOSED_INITIALIZER_P (init)
5634 || TREE_CODE (init) == STRING_CST))
5635 {
5636 cp_complete_array_type (&ttype, init, false);
5637 if (ttype != TREE_TYPE (type))
5638 type = cp_build_reference_type (ttype, TYPE_REF_IS_RVALUE (type));
5639 }
5640
5641 /* Convert INIT to the reference type TYPE. This may involve the
5642 creation of a temporary, whose lifetime must be the same as that
5643 of the reference. If so, a DECL_EXPR for the temporary will be
5644 added just after the DECL_EXPR for DECL. That's why we don't set
5645 DECL_INITIAL for local references (instead assigning to them
5646 explicitly); we need to allow the temporary to be initialized
5647 first. */
5648 return initialize_reference (type, init, flags,
5649 tf_warning_or_error);
5650 }
5651
5652 /* Designated initializers in arrays are not supported in GNU C++.
5653 The parser cannot detect this error since it does not know whether
5654 a given brace-enclosed initializer is for a class type or for an
5655 array. This function checks that CE does not use a designated
5656 initializer. If it does, an error is issued. Returns true if CE
5657 is valid, i.e., does not have a designated initializer. */
5658
5659 bool
check_array_designated_initializer(constructor_elt * ce,unsigned HOST_WIDE_INT index)5660 check_array_designated_initializer (constructor_elt *ce,
5661 unsigned HOST_WIDE_INT index)
5662 {
5663 /* Designated initializers for array elements are not supported. */
5664 if (ce->index)
5665 {
5666 /* The parser only allows identifiers as designated
5667 initializers. */
5668 if (ce->index == error_mark_node)
5669 {
5670 error ("name used in a GNU-style designated "
5671 "initializer for an array");
5672 return false;
5673 }
5674 else if (identifier_p (ce->index))
5675 {
5676 error ("name %qD used in a GNU-style designated "
5677 "initializer for an array", ce->index);
5678 return false;
5679 }
5680
5681 tree ce_index = build_expr_type_conversion (WANT_INT | WANT_ENUM,
5682 ce->index, true);
5683 if (ce_index
5684 && INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (ce_index))
5685 && (TREE_CODE (ce_index = fold_non_dependent_expr (ce_index))
5686 == INTEGER_CST))
5687 {
5688 /* A C99 designator is OK if it matches the current index. */
5689 if (wi::to_wide (ce_index) == index)
5690 {
5691 ce->index = ce_index;
5692 return true;
5693 }
5694 else
5695 sorry ("non-trivial designated initializers not supported");
5696 }
5697 else
5698 error_at (cp_expr_loc_or_input_loc (ce->index),
5699 "C99 designator %qE is not an integral constant-expression",
5700 ce->index);
5701
5702 return false;
5703 }
5704
5705 return true;
5706 }
5707
5708 /* When parsing `int a[] = {1, 2};' we don't know the size of the
5709 array until we finish parsing the initializer. If that's the
5710 situation we're in, update DECL accordingly. */
5711
5712 static void
maybe_deduce_size_from_array_init(tree decl,tree init)5713 maybe_deduce_size_from_array_init (tree decl, tree init)
5714 {
5715 tree type = TREE_TYPE (decl);
5716
5717 if (TREE_CODE (type) == ARRAY_TYPE
5718 && TYPE_DOMAIN (type) == NULL_TREE
5719 && TREE_CODE (decl) != TYPE_DECL)
5720 {
5721 /* do_default is really a C-ism to deal with tentative definitions.
5722 But let's leave it here to ease the eventual merge. */
5723 int do_default = !DECL_EXTERNAL (decl);
5724 tree initializer = init ? init : DECL_INITIAL (decl);
5725 int failure = 0;
5726
5727 /* Check that there are no designated initializers in INIT, as
5728 those are not supported in GNU C++, and as the middle-end
5729 will crash if presented with a non-numeric designated
5730 initializer. */
5731 if (initializer && BRACE_ENCLOSED_INITIALIZER_P (initializer))
5732 {
5733 vec<constructor_elt, va_gc> *v = CONSTRUCTOR_ELTS (initializer);
5734 constructor_elt *ce;
5735 HOST_WIDE_INT i;
5736 FOR_EACH_VEC_SAFE_ELT (v, i, ce)
5737 {
5738 if (instantiation_dependent_expression_p (ce->index))
5739 return;
5740 if (!check_array_designated_initializer (ce, i))
5741 failure = 1;
5742 }
5743 }
5744
5745 if (failure)
5746 TREE_TYPE (decl) = error_mark_node;
5747 else
5748 {
5749 failure = cp_complete_array_type (&TREE_TYPE (decl), initializer,
5750 do_default);
5751 if (failure == 1)
5752 {
5753 error_at (cp_expr_loc_or_loc (initializer,
5754 DECL_SOURCE_LOCATION (decl)),
5755 "initializer fails to determine size of %qD", decl);
5756 }
5757 else if (failure == 2)
5758 {
5759 if (do_default)
5760 {
5761 error_at (DECL_SOURCE_LOCATION (decl),
5762 "array size missing in %qD", decl);
5763 }
5764 /* If a `static' var's size isn't known, make it extern as
5765 well as static, so it does not get allocated. If it's not
5766 `static', then don't mark it extern; finish_incomplete_decl
5767 will give it a default size and it will get allocated. */
5768 else if (!pedantic && TREE_STATIC (decl) && !TREE_PUBLIC (decl))
5769 DECL_EXTERNAL (decl) = 1;
5770 }
5771 else if (failure == 3)
5772 {
5773 error_at (DECL_SOURCE_LOCATION (decl),
5774 "zero-size array %qD", decl);
5775 }
5776 }
5777
5778 cp_apply_type_quals_to_decl (cp_type_quals (TREE_TYPE (decl)), decl);
5779
5780 relayout_decl (decl);
5781 }
5782 }
5783
5784 /* Set DECL_SIZE, DECL_ALIGN, etc. for DECL (a VAR_DECL), and issue
5785 any appropriate error messages regarding the layout. */
5786
5787 static void
layout_var_decl(tree decl)5788 layout_var_decl (tree decl)
5789 {
5790 tree type;
5791
5792 type = TREE_TYPE (decl);
5793 if (type == error_mark_node)
5794 return;
5795
5796 /* If we haven't already laid out this declaration, do so now.
5797 Note that we must not call complete type for an external object
5798 because it's type might involve templates that we are not
5799 supposed to instantiate yet. (And it's perfectly valid to say
5800 `extern X x' for some incomplete type `X'.) */
5801 if (!DECL_EXTERNAL (decl))
5802 complete_type (type);
5803 if (!DECL_SIZE (decl)
5804 && TREE_TYPE (decl) != error_mark_node
5805 && complete_or_array_type_p (type))
5806 layout_decl (decl, 0);
5807
5808 if (!DECL_EXTERNAL (decl) && DECL_SIZE (decl) == NULL_TREE)
5809 {
5810 /* An automatic variable with an incomplete type: that is an error.
5811 Don't talk about array types here, since we took care of that
5812 message in grokdeclarator. */
5813 error_at (DECL_SOURCE_LOCATION (decl),
5814 "storage size of %qD isn%'t known", decl);
5815 TREE_TYPE (decl) = error_mark_node;
5816 }
5817 #if 0
5818 /* Keep this code around in case we later want to control debug info
5819 based on whether a type is "used". (jason 1999-11-11) */
5820
5821 else if (!DECL_EXTERNAL (decl) && MAYBE_CLASS_TYPE_P (ttype))
5822 /* Let debugger know it should output info for this type. */
5823 note_debug_info_needed (ttype);
5824
5825 if (TREE_STATIC (decl) && DECL_CLASS_SCOPE_P (decl))
5826 note_debug_info_needed (DECL_CONTEXT (decl));
5827 #endif
5828
5829 if ((DECL_EXTERNAL (decl) || TREE_STATIC (decl))
5830 && DECL_SIZE (decl) != NULL_TREE
5831 && ! TREE_CONSTANT (DECL_SIZE (decl)))
5832 {
5833 if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST)
5834 constant_expression_warning (DECL_SIZE (decl));
5835 else
5836 {
5837 error_at (DECL_SOURCE_LOCATION (decl),
5838 "storage size of %qD isn%'t constant", decl);
5839 TREE_TYPE (decl) = error_mark_node;
5840 }
5841 }
5842 }
5843
5844 /* If a local static variable is declared in an inline function, or if
5845 we have a weak definition, we must endeavor to create only one
5846 instance of the variable at link-time. */
5847
5848 void
maybe_commonize_var(tree decl)5849 maybe_commonize_var (tree decl)
5850 {
5851 /* Don't mess with __FUNCTION__ and similar. */
5852 if (DECL_ARTIFICIAL (decl))
5853 return;
5854
5855 /* Static data in a function with comdat linkage also has comdat
5856 linkage. */
5857 if ((TREE_STATIC (decl)
5858 && DECL_FUNCTION_SCOPE_P (decl)
5859 && vague_linkage_p (DECL_CONTEXT (decl)))
5860 || (TREE_PUBLIC (decl) && DECL_INLINE_VAR_P (decl)))
5861 {
5862 if (flag_weak)
5863 {
5864 /* With weak symbols, we simply make the variable COMDAT;
5865 that will cause copies in multiple translations units to
5866 be merged. */
5867 comdat_linkage (decl);
5868 }
5869 else
5870 {
5871 if (DECL_INITIAL (decl) == NULL_TREE
5872 || DECL_INITIAL (decl) == error_mark_node)
5873 {
5874 /* Without weak symbols, we can use COMMON to merge
5875 uninitialized variables. */
5876 TREE_PUBLIC (decl) = 1;
5877 DECL_COMMON (decl) = 1;
5878 }
5879 else
5880 {
5881 /* While for initialized variables, we must use internal
5882 linkage -- which means that multiple copies will not
5883 be merged. */
5884 TREE_PUBLIC (decl) = 0;
5885 DECL_COMMON (decl) = 0;
5886 DECL_INTERFACE_KNOWN (decl) = 1;
5887 const char *msg;
5888 if (DECL_INLINE_VAR_P (decl))
5889 msg = G_("sorry: semantics of inline variable "
5890 "%q#D are wrong (you%'ll wind up with "
5891 "multiple copies)");
5892 else
5893 msg = G_("sorry: semantics of inline function "
5894 "static data %q#D are wrong (you%'ll wind "
5895 "up with multiple copies)");
5896 if (warning_at (DECL_SOURCE_LOCATION (decl), 0,
5897 msg, decl))
5898 inform (DECL_SOURCE_LOCATION (decl),
5899 "you can work around this by removing the initializer");
5900 }
5901 }
5902 }
5903 }
5904
5905 /* Issue an error message if DECL is an uninitialized const variable.
5906 CONSTEXPR_CONTEXT_P is true when the function is called in a constexpr
5907 context from potential_constant_expression. Returns true if all is well,
5908 false otherwise. */
5909
5910 bool
check_for_uninitialized_const_var(tree decl,bool constexpr_context_p,tsubst_flags_t complain)5911 check_for_uninitialized_const_var (tree decl, bool constexpr_context_p,
5912 tsubst_flags_t complain)
5913 {
5914 tree type = strip_array_types (TREE_TYPE (decl));
5915
5916 /* ``Unless explicitly declared extern, a const object does not have
5917 external linkage and must be initialized. ($8.4; $12.1)'' ARM
5918 7.1.6 */
5919 if (VAR_P (decl)
5920 && !TYPE_REF_P (type)
5921 && (CP_TYPE_CONST_P (type)
5922 /* C++20 permits trivial default initialization in constexpr
5923 context (P1331R2). */
5924 || (cxx_dialect < cxx2a
5925 && (constexpr_context_p
5926 || var_in_constexpr_fn (decl))))
5927 && !DECL_NONTRIVIALLY_INITIALIZED_P (decl))
5928 {
5929 tree field = default_init_uninitialized_part (type);
5930 if (!field)
5931 return true;
5932
5933 bool show_notes = true;
5934
5935 if (!constexpr_context_p || cxx_dialect >= cxx2a)
5936 {
5937 if (CP_TYPE_CONST_P (type))
5938 {
5939 if (complain & tf_error)
5940 show_notes = permerror (DECL_SOURCE_LOCATION (decl),
5941 "uninitialized %<const %D%>", decl);
5942 }
5943 else
5944 {
5945 if (!is_instantiation_of_constexpr (current_function_decl)
5946 && (complain & tf_error))
5947 error_at (DECL_SOURCE_LOCATION (decl),
5948 "uninitialized variable %qD in %<constexpr%> "
5949 "function", decl);
5950 else
5951 show_notes = false;
5952 cp_function_chain->invalid_constexpr = true;
5953 }
5954 }
5955 else if (complain & tf_error)
5956 error_at (DECL_SOURCE_LOCATION (decl),
5957 "uninitialized variable %qD in %<constexpr%> context",
5958 decl);
5959
5960 if (show_notes && CLASS_TYPE_P (type) && (complain & tf_error))
5961 {
5962 tree defaulted_ctor;
5963
5964 inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (type)),
5965 "%q#T has no user-provided default constructor", type);
5966 defaulted_ctor = in_class_defaulted_default_constructor (type);
5967 if (defaulted_ctor)
5968 inform (DECL_SOURCE_LOCATION (defaulted_ctor),
5969 "constructor is not user-provided because it is "
5970 "explicitly defaulted in the class body");
5971 inform (DECL_SOURCE_LOCATION (field),
5972 "and the implicitly-defined constructor does not "
5973 "initialize %q#D", field);
5974 }
5975
5976 return false;
5977 }
5978
5979 return true;
5980 }
5981
5982 /* Structure holding the current initializer being processed by reshape_init.
5983 CUR is a pointer to the current element being processed, END is a pointer
5984 after the last element present in the initializer. */
5985 struct reshape_iter
5986 {
5987 constructor_elt *cur;
5988 constructor_elt *end;
5989 };
5990
5991 static tree reshape_init_r (tree, reshape_iter *, tree, tsubst_flags_t);
5992
5993 /* FIELD is a FIELD_DECL or NULL. In the former case, the value
5994 returned is the next FIELD_DECL (possibly FIELD itself) that can be
5995 initialized. If there are no more such fields, the return value
5996 will be NULL. */
5997
5998 tree
next_initializable_field(tree field)5999 next_initializable_field (tree field)
6000 {
6001 while (field
6002 && (TREE_CODE (field) != FIELD_DECL
6003 || DECL_UNNAMED_BIT_FIELD (field)
6004 || (DECL_ARTIFICIAL (field)
6005 /* In C++17, don't skip base class fields. */
6006 && !(cxx_dialect >= cxx17 && DECL_FIELD_IS_BASE (field))
6007 /* Don't skip vptr fields. We might see them when we're
6008 called from reduced_constant_expression_p. */
6009 && !DECL_VIRTUAL_P (field))))
6010 field = DECL_CHAIN (field);
6011
6012 return field;
6013 }
6014
6015 /* Return true for [dcl.init.list] direct-list-initialization from
6016 single element of enumeration with a fixed underlying type. */
6017
6018 bool
is_direct_enum_init(tree type,tree init)6019 is_direct_enum_init (tree type, tree init)
6020 {
6021 if (cxx_dialect >= cxx17
6022 && TREE_CODE (type) == ENUMERAL_TYPE
6023 && ENUM_FIXED_UNDERLYING_TYPE_P (type)
6024 && TREE_CODE (init) == CONSTRUCTOR
6025 && CONSTRUCTOR_IS_DIRECT_INIT (init)
6026 && CONSTRUCTOR_NELTS (init) == 1)
6027 return true;
6028 return false;
6029 }
6030
6031 /* Subroutine of reshape_init_array and reshape_init_vector, which does
6032 the actual work. ELT_TYPE is the element type of the array. MAX_INDEX is an
6033 INTEGER_CST representing the size of the array minus one (the maximum index),
6034 or NULL_TREE if the array was declared without specifying the size. D is
6035 the iterator within the constructor. */
6036
6037 static tree
reshape_init_array_1(tree elt_type,tree max_index,reshape_iter * d,tree first_initializer_p,tsubst_flags_t complain)6038 reshape_init_array_1 (tree elt_type, tree max_index, reshape_iter *d,
6039 tree first_initializer_p, tsubst_flags_t complain)
6040 {
6041 tree new_init;
6042 bool sized_array_p = (max_index && TREE_CONSTANT (max_index));
6043 unsigned HOST_WIDE_INT max_index_cst = 0;
6044 unsigned HOST_WIDE_INT index;
6045
6046 /* The initializer for an array is always a CONSTRUCTOR. If this is the
6047 outermost CONSTRUCTOR and the element type is non-aggregate, we don't need
6048 to build a new one. But don't reuse if not complaining; if this is
6049 tentative, we might also reshape to another type (95319). */
6050 bool reuse = (first_initializer_p
6051 && (complain & tf_error)
6052 && !CP_AGGREGATE_TYPE_P (elt_type)
6053 && !TREE_SIDE_EFFECTS (first_initializer_p));
6054 if (reuse)
6055 new_init = first_initializer_p;
6056 else
6057 new_init = build_constructor (init_list_type_node, NULL);
6058
6059 if (sized_array_p)
6060 {
6061 /* Minus 1 is used for zero sized arrays. */
6062 if (integer_all_onesp (max_index))
6063 return new_init;
6064
6065 if (tree_fits_uhwi_p (max_index))
6066 max_index_cst = tree_to_uhwi (max_index);
6067 /* sizetype is sign extended, not zero extended. */
6068 else
6069 max_index_cst = tree_to_uhwi (fold_convert (size_type_node, max_index));
6070 }
6071
6072 /* Loop until there are no more initializers. */
6073 for (index = 0;
6074 d->cur != d->end && (!sized_array_p || index <= max_index_cst);
6075 ++index)
6076 {
6077 tree elt_init;
6078 constructor_elt *old_cur = d->cur;
6079
6080 check_array_designated_initializer (d->cur, index);
6081 elt_init = reshape_init_r (elt_type, d,
6082 /*first_initializer_p=*/NULL_TREE,
6083 complain);
6084 if (elt_init == error_mark_node)
6085 return error_mark_node;
6086 tree idx = size_int (index);
6087 if (reuse)
6088 {
6089 old_cur->index = idx;
6090 old_cur->value = elt_init;
6091 }
6092 else
6093 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_init),
6094 idx, elt_init);
6095 if (!TREE_CONSTANT (elt_init))
6096 TREE_CONSTANT (new_init) = false;
6097
6098 /* This can happen with an invalid initializer (c++/54501). */
6099 if (d->cur == old_cur && !sized_array_p)
6100 break;
6101 }
6102
6103 return new_init;
6104 }
6105
6106 /* Subroutine of reshape_init_r, processes the initializers for arrays.
6107 Parameters are the same of reshape_init_r. */
6108
6109 static tree
reshape_init_array(tree type,reshape_iter * d,tree first_initializer_p,tsubst_flags_t complain)6110 reshape_init_array (tree type, reshape_iter *d, tree first_initializer_p,
6111 tsubst_flags_t complain)
6112 {
6113 tree max_index = NULL_TREE;
6114
6115 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
6116
6117 if (TYPE_DOMAIN (type))
6118 max_index = array_type_nelts (type);
6119
6120 return reshape_init_array_1 (TREE_TYPE (type), max_index, d,
6121 first_initializer_p, complain);
6122 }
6123
6124 /* Subroutine of reshape_init_r, processes the initializers for vectors.
6125 Parameters are the same of reshape_init_r. */
6126
6127 static tree
reshape_init_vector(tree type,reshape_iter * d,tsubst_flags_t complain)6128 reshape_init_vector (tree type, reshape_iter *d, tsubst_flags_t complain)
6129 {
6130 tree max_index = NULL_TREE;
6131
6132 gcc_assert (VECTOR_TYPE_P (type));
6133
6134 if (COMPOUND_LITERAL_P (d->cur->value))
6135 {
6136 tree value = d->cur->value;
6137 if (!same_type_p (TREE_TYPE (value), type))
6138 {
6139 if (complain & tf_error)
6140 error ("invalid type %qT as initializer for a vector of type %qT",
6141 TREE_TYPE (d->cur->value), type);
6142 value = error_mark_node;
6143 }
6144 ++d->cur;
6145 return value;
6146 }
6147
6148 /* For a vector, we initialize it as an array of the appropriate size. */
6149 if (VECTOR_TYPE_P (type))
6150 max_index = size_int (TYPE_VECTOR_SUBPARTS (type) - 1);
6151
6152 return reshape_init_array_1 (TREE_TYPE (type), max_index, d,
6153 NULL_TREE, complain);
6154 }
6155
6156 /* Subroutine of reshape_init_r, processes the initializers for classes
6157 or union. Parameters are the same of reshape_init_r. */
6158
6159 static tree
reshape_init_class(tree type,reshape_iter * d,bool first_initializer_p,tsubst_flags_t complain)6160 reshape_init_class (tree type, reshape_iter *d, bool first_initializer_p,
6161 tsubst_flags_t complain)
6162 {
6163 tree field;
6164 tree new_init;
6165
6166 gcc_assert (CLASS_TYPE_P (type));
6167
6168 /* The initializer for a class is always a CONSTRUCTOR. */
6169 new_init = build_constructor (init_list_type_node, NULL);
6170 field = next_initializable_field (TYPE_FIELDS (type));
6171
6172 if (!field)
6173 {
6174 /* [dcl.init.aggr]
6175
6176 An initializer for an aggregate member that is an
6177 empty class shall have the form of an empty
6178 initializer-list {}. */
6179 if (!first_initializer_p)
6180 {
6181 if (complain & tf_error)
6182 error ("initializer for %qT must be brace-enclosed", type);
6183 return error_mark_node;
6184 }
6185 return new_init;
6186 }
6187
6188 /* Loop through the initializable fields, gathering initializers. */
6189 while (d->cur != d->end)
6190 {
6191 tree field_init;
6192 constructor_elt *old_cur = d->cur;
6193
6194 /* Handle designated initializers, as an extension. */
6195 if (d->cur->index)
6196 {
6197 if (d->cur->index == error_mark_node)
6198 return error_mark_node;
6199
6200 if (TREE_CODE (d->cur->index) == FIELD_DECL)
6201 {
6202 /* We already reshaped this. */
6203 if (field != d->cur->index)
6204 {
6205 tree id = DECL_NAME (d->cur->index);
6206 gcc_assert (id);
6207 gcc_checking_assert (d->cur->index
6208 == get_class_binding (type, id));
6209 field = d->cur->index;
6210 }
6211 }
6212 else if (TREE_CODE (d->cur->index) == IDENTIFIER_NODE)
6213 field = get_class_binding (type, d->cur->index);
6214 else
6215 {
6216 if (complain & tf_error)
6217 error ("%<[%E] =%> used in a GNU-style designated initializer"
6218 " for class %qT", d->cur->index, type);
6219 return error_mark_node;
6220 }
6221
6222 if (!field || TREE_CODE (field) != FIELD_DECL)
6223 {
6224 if (complain & tf_error)
6225 error ("%qT has no non-static data member named %qD", type,
6226 d->cur->index);
6227 return error_mark_node;
6228 }
6229 }
6230
6231 /* If we processed all the member of the class, we are done. */
6232 if (!field)
6233 break;
6234
6235 field_init = reshape_init_r (TREE_TYPE (field), d,
6236 /*first_initializer_p=*/NULL_TREE,
6237 complain);
6238 if (field_init == error_mark_node)
6239 return error_mark_node;
6240
6241 if (d->cur == old_cur && d->cur->index)
6242 {
6243 /* This can happen with an invalid initializer for a flexible
6244 array member (c++/54441). */
6245 if (complain & tf_error)
6246 error ("invalid initializer for %q#D", field);
6247 return error_mark_node;
6248 }
6249
6250 CONSTRUCTOR_APPEND_ELT (CONSTRUCTOR_ELTS (new_init), field, field_init);
6251
6252 /* [dcl.init.aggr]
6253
6254 When a union is initialized with a brace-enclosed
6255 initializer, the braces shall only contain an
6256 initializer for the first member of the union. */
6257 if (TREE_CODE (type) == UNION_TYPE)
6258 break;
6259
6260 field = next_initializable_field (DECL_CHAIN (field));
6261 }
6262
6263 return new_init;
6264 }
6265
6266 /* Subroutine of reshape_init_r. We're in a context where C99 initializer
6267 designators are not valid; either complain or return true to indicate
6268 that reshape_init_r should return error_mark_node. */
6269
6270 static bool
has_designator_problem(reshape_iter * d,tsubst_flags_t complain)6271 has_designator_problem (reshape_iter *d, tsubst_flags_t complain)
6272 {
6273 if (d->cur->index)
6274 {
6275 if (complain & tf_error)
6276 error_at (cp_expr_loc_or_input_loc (d->cur->index),
6277 "C99 designator %qE outside aggregate initializer",
6278 d->cur->index);
6279 else
6280 return true;
6281 }
6282 return false;
6283 }
6284
6285 /* Subroutine of reshape_init, which processes a single initializer (part of
6286 a CONSTRUCTOR). TYPE is the type of the variable being initialized, D is the
6287 iterator within the CONSTRUCTOR which points to the initializer to process.
6288 If this is the first initializer of the outermost CONSTRUCTOR node,
6289 FIRST_INITIALIZER_P is that CONSTRUCTOR; otherwise, it is NULL_TREE. */
6290
6291 static tree
reshape_init_r(tree type,reshape_iter * d,tree first_initializer_p,tsubst_flags_t complain)6292 reshape_init_r (tree type, reshape_iter *d, tree first_initializer_p,
6293 tsubst_flags_t complain)
6294 {
6295 tree init = d->cur->value;
6296
6297 if (error_operand_p (init))
6298 return error_mark_node;
6299
6300 if (first_initializer_p && !CP_AGGREGATE_TYPE_P (type)
6301 && has_designator_problem (d, complain))
6302 return error_mark_node;
6303
6304 tree stripped_init = tree_strip_any_location_wrapper (init);
6305
6306 if (TREE_CODE (type) == COMPLEX_TYPE)
6307 {
6308 /* A complex type can be initialized from one or two initializers,
6309 but braces are not elided. */
6310 d->cur++;
6311 if (BRACE_ENCLOSED_INITIALIZER_P (stripped_init))
6312 {
6313 if (CONSTRUCTOR_NELTS (stripped_init) > 2)
6314 {
6315 if (complain & tf_error)
6316 error ("too many initializers for %qT", type);
6317 else
6318 return error_mark_node;
6319 }
6320 }
6321 else if (first_initializer_p && d->cur != d->end)
6322 {
6323 vec<constructor_elt, va_gc> *v = 0;
6324 CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, init);
6325 CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, d->cur->value);
6326 if (has_designator_problem (d, complain))
6327 return error_mark_node;
6328 d->cur++;
6329 init = build_constructor (init_list_type_node, v);
6330 }
6331 return init;
6332 }
6333
6334 /* A non-aggregate type is always initialized with a single
6335 initializer. */
6336 if (!CP_AGGREGATE_TYPE_P (type))
6337 {
6338 /* It is invalid to initialize a non-aggregate type with a
6339 brace-enclosed initializer before C++0x.
6340 We need to check for BRACE_ENCLOSED_INITIALIZER_P here because
6341 of g++.old-deja/g++.mike/p7626.C: a pointer-to-member constant is
6342 a CONSTRUCTOR (with a record type). */
6343 if (TREE_CODE (stripped_init) == CONSTRUCTOR
6344 /* Don't complain about a capture-init. */
6345 && !CONSTRUCTOR_IS_DIRECT_INIT (stripped_init)
6346 && BRACE_ENCLOSED_INITIALIZER_P (stripped_init)) /* p7626.C */
6347 {
6348 if (SCALAR_TYPE_P (type))
6349 {
6350 if (cxx_dialect < cxx11)
6351 {
6352 if (complain & tf_error)
6353 error ("braces around scalar initializer for type %qT",
6354 type);
6355 init = error_mark_node;
6356 }
6357 else if (first_initializer_p
6358 || (CONSTRUCTOR_NELTS (stripped_init) > 0
6359 && (BRACE_ENCLOSED_INITIALIZER_P
6360 (CONSTRUCTOR_ELT (stripped_init,0)->value))))
6361 {
6362 if (complain & tf_error)
6363 error ("too many braces around scalar initializer "
6364 "for type %qT", type);
6365 init = error_mark_node;
6366 }
6367 }
6368 else
6369 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
6370 }
6371
6372 d->cur++;
6373 return init;
6374 }
6375
6376 /* "If T is a class type and the initializer list has a single element of
6377 type cv U, where U is T or a class derived from T, the object is
6378 initialized from that element." Even if T is an aggregate. */
6379 if (cxx_dialect >= cxx11 && (CLASS_TYPE_P (type) || VECTOR_TYPE_P (type))
6380 && first_initializer_p
6381 && d->end - d->cur == 1
6382 && reference_related_p (type, TREE_TYPE (init)))
6383 {
6384 d->cur++;
6385 return init;
6386 }
6387
6388 /* [dcl.init.aggr]
6389
6390 All implicit type conversions (clause _conv_) are considered when
6391 initializing the aggregate member with an initializer from an
6392 initializer-list. If the initializer can initialize a member,
6393 the member is initialized. Otherwise, if the member is itself a
6394 non-empty subaggregate, brace elision is assumed and the
6395 initializer is considered for the initialization of the first
6396 member of the subaggregate. */
6397 if ((TREE_CODE (init) != CONSTRUCTOR || COMPOUND_LITERAL_P (init))
6398 /* But don't try this for the first initializer, since that would be
6399 looking through the outermost braces; A a2 = { a1 }; is not a
6400 valid aggregate initialization. */
6401 && !first_initializer_p
6402 && (same_type_ignoring_top_level_qualifiers_p (type, TREE_TYPE (init))
6403 || can_convert_arg (type, TREE_TYPE (init), init, LOOKUP_NORMAL,
6404 complain)))
6405 {
6406 d->cur++;
6407 return init;
6408 }
6409
6410 /* [dcl.init.string]
6411
6412 A char array (whether plain char, signed char, or unsigned char)
6413 can be initialized by a string-literal (optionally enclosed in
6414 braces); a wchar_t array can be initialized by a wide
6415 string-literal (optionally enclosed in braces). */
6416 if (TREE_CODE (type) == ARRAY_TYPE
6417 && char_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (type))))
6418 {
6419 tree str_init = init;
6420 tree stripped_str_init = stripped_init;
6421
6422 /* Strip one level of braces if and only if they enclose a single
6423 element (as allowed by [dcl.init.string]). */
6424 if (!first_initializer_p
6425 && TREE_CODE (stripped_str_init) == CONSTRUCTOR
6426 && CONSTRUCTOR_NELTS (stripped_str_init) == 1)
6427 {
6428 str_init = (*CONSTRUCTOR_ELTS (stripped_str_init))[0].value;
6429 stripped_str_init = tree_strip_any_location_wrapper (str_init);
6430 }
6431
6432 /* If it's a string literal, then it's the initializer for the array
6433 as a whole. Otherwise, continue with normal initialization for
6434 array types (one value per array element). */
6435 if (TREE_CODE (stripped_str_init) == STRING_CST)
6436 {
6437 if (has_designator_problem (d, complain))
6438 return error_mark_node;
6439 d->cur++;
6440 return str_init;
6441 }
6442 }
6443
6444 /* The following cases are about aggregates. If we are not within a full
6445 initializer already, and there is not a CONSTRUCTOR, it means that there
6446 is a missing set of braces (that is, we are processing the case for
6447 which reshape_init exists). */
6448 if (!first_initializer_p)
6449 {
6450 if (TREE_CODE (stripped_init) == CONSTRUCTOR)
6451 {
6452 tree init_type = TREE_TYPE (init);
6453 if (init_type && TYPE_PTRMEMFUNC_P (init_type))
6454 /* There is no need to call reshape_init for pointer-to-member
6455 function initializers, as they are always constructed correctly
6456 by the front end. Here we have e.g. {.__pfn=0B, .__delta=0},
6457 which is missing outermost braces. We should warn below, and
6458 one of the routines below will wrap it in additional { }. */;
6459 /* For a nested compound literal, proceed to specialized routines,
6460 to handle initialization of arrays and similar. */
6461 else if (COMPOUND_LITERAL_P (stripped_init))
6462 gcc_assert (!BRACE_ENCLOSED_INITIALIZER_P (stripped_init));
6463 /* A CONSTRUCTOR of the target's type is a previously
6464 digested initializer. */
6465 else if (same_type_ignoring_top_level_qualifiers_p (type, init_type))
6466 {
6467 ++d->cur;
6468 return init;
6469 }
6470 else
6471 {
6472 /* Something that hasn't been reshaped yet. */
6473 ++d->cur;
6474 gcc_assert (BRACE_ENCLOSED_INITIALIZER_P (stripped_init));
6475 return reshape_init (type, init, complain);
6476 }
6477 }
6478
6479 if (complain & tf_warning)
6480 warning (OPT_Wmissing_braces,
6481 "missing braces around initializer for %qT",
6482 type);
6483 }
6484
6485 /* Dispatch to specialized routines. */
6486 if (CLASS_TYPE_P (type))
6487 return reshape_init_class (type, d, first_initializer_p, complain);
6488 else if (TREE_CODE (type) == ARRAY_TYPE)
6489 return reshape_init_array (type, d, first_initializer_p, complain);
6490 else if (VECTOR_TYPE_P (type))
6491 return reshape_init_vector (type, d, complain);
6492 else
6493 gcc_unreachable();
6494 }
6495
6496 /* Undo the brace-elision allowed by [dcl.init.aggr] in a
6497 brace-enclosed aggregate initializer.
6498
6499 INIT is the CONSTRUCTOR containing the list of initializers describing
6500 a brace-enclosed initializer for an entity of the indicated aggregate TYPE.
6501 It may not presently match the shape of the TYPE; for example:
6502
6503 struct S { int a; int b; };
6504 struct S a[] = { 1, 2, 3, 4 };
6505
6506 Here INIT will hold a vector of four elements, rather than a
6507 vector of two elements, each itself a vector of two elements. This
6508 routine transforms INIT from the former form into the latter. The
6509 revised CONSTRUCTOR node is returned. */
6510
6511 tree
reshape_init(tree type,tree init,tsubst_flags_t complain)6512 reshape_init (tree type, tree init, tsubst_flags_t complain)
6513 {
6514 vec<constructor_elt, va_gc> *v;
6515 reshape_iter d;
6516 tree new_init;
6517
6518 gcc_assert (BRACE_ENCLOSED_INITIALIZER_P (init));
6519
6520 v = CONSTRUCTOR_ELTS (init);
6521
6522 /* An empty constructor does not need reshaping, and it is always a valid
6523 initializer. */
6524 if (vec_safe_is_empty (v))
6525 return init;
6526
6527 /* Brace elision is not performed for a CONSTRUCTOR representing
6528 parenthesized aggregate initialization. */
6529 if (CONSTRUCTOR_IS_PAREN_INIT (init))
6530 return init;
6531
6532 /* Handle [dcl.init.list] direct-list-initialization from
6533 single element of enumeration with a fixed underlying type. */
6534 if (is_direct_enum_init (type, init))
6535 {
6536 tree elt = CONSTRUCTOR_ELT (init, 0)->value;
6537 type = cv_unqualified (type);
6538 if (check_narrowing (ENUM_UNDERLYING_TYPE (type), elt, complain))
6539 {
6540 warning_sentinel w (warn_useless_cast);
6541 warning_sentinel w2 (warn_ignored_qualifiers);
6542 return cp_build_c_cast (input_location, type, elt,
6543 tf_warning_or_error);
6544 }
6545 else
6546 return error_mark_node;
6547 }
6548
6549 /* Recurse on this CONSTRUCTOR. */
6550 d.cur = &(*v)[0];
6551 d.end = d.cur + v->length ();
6552
6553 new_init = reshape_init_r (type, &d, init, complain);
6554 if (new_init == error_mark_node)
6555 return error_mark_node;
6556
6557 /* Make sure all the element of the constructor were used. Otherwise,
6558 issue an error about exceeding initializers. */
6559 if (d.cur != d.end)
6560 {
6561 if (complain & tf_error)
6562 error ("too many initializers for %qT", type);
6563 return error_mark_node;
6564 }
6565
6566 if (CONSTRUCTOR_IS_DIRECT_INIT (init)
6567 && BRACE_ENCLOSED_INITIALIZER_P (new_init))
6568 CONSTRUCTOR_IS_DIRECT_INIT (new_init) = true;
6569 if (CONSTRUCTOR_IS_DESIGNATED_INIT (init)
6570 && BRACE_ENCLOSED_INITIALIZER_P (new_init))
6571 CONSTRUCTOR_IS_DESIGNATED_INIT (new_init) = true;
6572
6573 return new_init;
6574 }
6575
6576 /* Verify array initializer. Returns true if errors have been reported. */
6577
6578 bool
check_array_initializer(tree decl,tree type,tree init)6579 check_array_initializer (tree decl, tree type, tree init)
6580 {
6581 tree element_type = TREE_TYPE (type);
6582
6583 /* Structured binding when initialized with an array type needs
6584 to have complete type. */
6585 if (decl
6586 && DECL_DECOMPOSITION_P (decl)
6587 && !DECL_DECOMP_BASE (decl)
6588 && !COMPLETE_TYPE_P (type))
6589 {
6590 error_at (DECL_SOURCE_LOCATION (decl),
6591 "structured binding has incomplete type %qT", type);
6592 TREE_TYPE (decl) = error_mark_node;
6593 return true;
6594 }
6595
6596 /* The array type itself need not be complete, because the
6597 initializer may tell us how many elements are in the array.
6598 But, the elements of the array must be complete. */
6599 if (!COMPLETE_TYPE_P (complete_type (element_type)))
6600 {
6601 if (decl)
6602 error_at (DECL_SOURCE_LOCATION (decl),
6603 "elements of array %q#D have incomplete type", decl);
6604 else
6605 error ("elements of array %q#T have incomplete type", type);
6606 return true;
6607 }
6608
6609 location_t loc = (decl ? location_of (decl) : input_location);
6610 if (!verify_type_context (loc, TCTX_ARRAY_ELEMENT, element_type))
6611 return true;
6612
6613 /* A compound literal can't have variable size. */
6614 if (init && !decl
6615 && ((COMPLETE_TYPE_P (type) && !TREE_CONSTANT (TYPE_SIZE (type)))
6616 || !TREE_CONSTANT (TYPE_SIZE (element_type))))
6617 {
6618 error ("variable-sized compound literal");
6619 return true;
6620 }
6621 return false;
6622 }
6623
6624 /* Subroutine of check_initializer; args are passed down from that function.
6625 Set stmts_are_full_exprs_p to 1 across a call to build_aggr_init. */
6626
6627 static tree
build_aggr_init_full_exprs(tree decl,tree init,int flags)6628 build_aggr_init_full_exprs (tree decl, tree init, int flags)
6629
6630 {
6631 gcc_assert (stmts_are_full_exprs_p ());
6632 return build_aggr_init (decl, init, flags, tf_warning_or_error);
6633 }
6634
6635 /* Verify INIT (the initializer for DECL), and record the
6636 initialization in DECL_INITIAL, if appropriate. CLEANUP is as for
6637 grok_reference_init.
6638
6639 If the return value is non-NULL, it is an expression that must be
6640 evaluated dynamically to initialize DECL. */
6641
6642 static tree
check_initializer(tree decl,tree init,int flags,vec<tree,va_gc> ** cleanups)6643 check_initializer (tree decl, tree init, int flags, vec<tree, va_gc> **cleanups)
6644 {
6645 tree type;
6646 tree init_code = NULL;
6647 tree core_type;
6648
6649 /* Things that are going to be initialized need to have complete
6650 type. */
6651 TREE_TYPE (decl) = type = complete_type (TREE_TYPE (decl));
6652
6653 if (DECL_HAS_VALUE_EXPR_P (decl))
6654 {
6655 /* A variable with DECL_HAS_VALUE_EXPR_P set is just a placeholder,
6656 it doesn't have storage to be initialized. */
6657 gcc_assert (init == NULL_TREE);
6658 return NULL_TREE;
6659 }
6660
6661 if (type == error_mark_node)
6662 /* We will have already complained. */
6663 return NULL_TREE;
6664
6665 if (TREE_CODE (type) == ARRAY_TYPE)
6666 {
6667 if (check_array_initializer (decl, type, init))
6668 return NULL_TREE;
6669 }
6670 else if (!COMPLETE_TYPE_P (type))
6671 {
6672 error_at (DECL_SOURCE_LOCATION (decl),
6673 "%q#D has incomplete type", decl);
6674 TREE_TYPE (decl) = error_mark_node;
6675 return NULL_TREE;
6676 }
6677 else
6678 /* There is no way to make a variable-sized class type in GNU C++. */
6679 gcc_assert (TREE_CONSTANT (TYPE_SIZE (type)));
6680
6681 if (init && BRACE_ENCLOSED_INITIALIZER_P (init))
6682 {
6683 int init_len = CONSTRUCTOR_NELTS (init);
6684 if (SCALAR_TYPE_P (type))
6685 {
6686 if (init_len == 0)
6687 {
6688 maybe_warn_cpp0x (CPP0X_INITIALIZER_LISTS);
6689 init = build_zero_init (type, NULL_TREE, false);
6690 }
6691 else if (init_len != 1 && TREE_CODE (type) != COMPLEX_TYPE)
6692 {
6693 error_at (cp_expr_loc_or_loc (init, DECL_SOURCE_LOCATION (decl)),
6694 "scalar object %qD requires one element in "
6695 "initializer", decl);
6696 TREE_TYPE (decl) = error_mark_node;
6697 return NULL_TREE;
6698 }
6699 }
6700 }
6701
6702 if (TREE_CODE (decl) == CONST_DECL)
6703 {
6704 gcc_assert (!TYPE_REF_P (type));
6705
6706 DECL_INITIAL (decl) = init;
6707
6708 gcc_assert (init != NULL_TREE);
6709 init = NULL_TREE;
6710 }
6711 else if (!init && DECL_REALLY_EXTERN (decl))
6712 ;
6713 else if (init || type_build_ctor_call (type)
6714 || TYPE_REF_P (type))
6715 {
6716 if (TYPE_REF_P (type))
6717 {
6718 init = grok_reference_init (decl, type, init, flags);
6719 flags |= LOOKUP_ALREADY_DIGESTED;
6720 }
6721 else if (!init)
6722 check_for_uninitialized_const_var (decl, /*constexpr_context_p=*/false,
6723 tf_warning_or_error);
6724 /* Do not reshape constructors of vectors (they don't need to be
6725 reshaped. */
6726 else if (BRACE_ENCLOSED_INITIALIZER_P (init))
6727 {
6728 if (is_std_init_list (type))
6729 {
6730 init = perform_implicit_conversion (type, init,
6731 tf_warning_or_error);
6732 flags |= LOOKUP_ALREADY_DIGESTED;
6733 }
6734 else if (TYPE_NON_AGGREGATE_CLASS (type))
6735 {
6736 /* Don't reshape if the class has constructors. */
6737 if (cxx_dialect == cxx98)
6738 error_at (cp_expr_loc_or_loc (init, DECL_SOURCE_LOCATION (decl)),
6739 "in C++98 %qD must be initialized by "
6740 "constructor, not by %<{...}%>",
6741 decl);
6742 }
6743 else if (VECTOR_TYPE_P (type) && TYPE_VECTOR_OPAQUE (type))
6744 {
6745 error ("opaque vector types cannot be initialized");
6746 init = error_mark_node;
6747 }
6748 else
6749 {
6750 init = reshape_init (type, init, tf_warning_or_error);
6751 flags |= LOOKUP_NO_NARROWING;
6752 }
6753 }
6754 /* [dcl.init] "Otherwise, if the destination type is an array, the object
6755 is initialized as follows..." So handle things like
6756
6757 int a[](1, 2, 3);
6758
6759 which is permitted in C++20 by P0960. */
6760 else if (TREE_CODE (init) == TREE_LIST
6761 && TREE_TYPE (init) == NULL_TREE
6762 && TREE_CODE (type) == ARRAY_TYPE
6763 && !DECL_DECOMPOSITION_P (decl)
6764 && (cxx_dialect >= cxx2a))
6765 {
6766 /* [dcl.init.string] "An array of ordinary character type [...]
6767 can be initialized by an ordinary string literal [...] by an
6768 appropriately-typed string literal enclosed in braces" only
6769 talks about braces, but GCC has always accepted
6770
6771 char a[]("foobar");
6772
6773 so we continue to do so. */
6774 tree val = TREE_VALUE (init);
6775 if (TREE_CHAIN (init) == NULL_TREE
6776 && char_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (type)))
6777 && TREE_CODE (tree_strip_any_location_wrapper (val))
6778 == STRING_CST)
6779 /* If the list has a single element and it's a string literal,
6780 then it's the initializer for the array as a whole. */
6781 init = val;
6782 else
6783 {
6784 init = build_constructor_from_list (init_list_type_node, init);
6785 CONSTRUCTOR_IS_DIRECT_INIT (init) = true;
6786 CONSTRUCTOR_IS_PAREN_INIT (init) = true;
6787 }
6788 }
6789 else if (TREE_CODE (init) == TREE_LIST
6790 && TREE_TYPE (init) != unknown_type_node
6791 && !MAYBE_CLASS_TYPE_P (type))
6792 {
6793 gcc_assert (TREE_CODE (decl) != RESULT_DECL);
6794
6795 /* We get here with code like `int a (2);' */
6796 init = build_x_compound_expr_from_list (init, ELK_INIT,
6797 tf_warning_or_error);
6798 }
6799
6800 /* If DECL has an array type without a specific bound, deduce the
6801 array size from the initializer. */
6802 maybe_deduce_size_from_array_init (decl, init);
6803 type = TREE_TYPE (decl);
6804 if (type == error_mark_node)
6805 return NULL_TREE;
6806
6807 if (((type_build_ctor_call (type) || CLASS_TYPE_P (type))
6808 && !(flags & LOOKUP_ALREADY_DIGESTED)
6809 && !(init && BRACE_ENCLOSED_INITIALIZER_P (init)
6810 && CP_AGGREGATE_TYPE_P (type)
6811 && (CLASS_TYPE_P (type)
6812 || !TYPE_NEEDS_CONSTRUCTING (type)
6813 || type_has_extended_temps (type))))
6814 || (DECL_DECOMPOSITION_P (decl) && TREE_CODE (type) == ARRAY_TYPE))
6815 {
6816 init_code = build_aggr_init_full_exprs (decl, init, flags);
6817
6818 /* A constructor call is a non-trivial initializer even if
6819 it isn't explicitly written. */
6820 if (TREE_SIDE_EFFECTS (init_code))
6821 DECL_NONTRIVIALLY_INITIALIZED_P (decl) = true;
6822
6823 /* If this is a constexpr initializer, expand_default_init will
6824 have returned an INIT_EXPR rather than a CALL_EXPR. In that
6825 case, pull the initializer back out and pass it down into
6826 store_init_value. */
6827 while (TREE_CODE (init_code) == EXPR_STMT
6828 || TREE_CODE (init_code) == CONVERT_EXPR)
6829 init_code = TREE_OPERAND (init_code, 0);
6830 if (TREE_CODE (init_code) == INIT_EXPR)
6831 {
6832 /* In C++20, the call to build_aggr_init could have created
6833 an INIT_EXPR with a CONSTRUCTOR as the RHS to handle
6834 A(1, 2). */
6835 init = TREE_OPERAND (init_code, 1);
6836 init_code = NULL_TREE;
6837 /* Don't call digest_init; it's unnecessary and will complain
6838 about aggregate initialization of non-aggregate classes. */
6839 flags |= LOOKUP_ALREADY_DIGESTED;
6840 }
6841 else if (DECL_DECLARED_CONSTEXPR_P (decl)
6842 || (flags & LOOKUP_CONSTINIT))
6843 {
6844 /* Declared constexpr or constinit, but no suitable initializer;
6845 massage init appropriately so we can pass it into
6846 store_init_value for the error. */
6847 if (CLASS_TYPE_P (type)
6848 && (!init || TREE_CODE (init) == TREE_LIST))
6849 {
6850 init = build_functional_cast (input_location, type,
6851 init, tf_none);
6852 if (TREE_CODE (init) == TARGET_EXPR)
6853 TARGET_EXPR_DIRECT_INIT_P (init) = true;
6854 }
6855 init_code = NULL_TREE;
6856 }
6857 else
6858 init = NULL_TREE;
6859 }
6860
6861 if (init && TREE_CODE (init) != TREE_VEC)
6862 {
6863 /* In aggregate initialization of a variable, each element
6864 initialization is a full-expression because there is no
6865 enclosing expression. */
6866 gcc_assert (stmts_are_full_exprs_p ());
6867
6868 init_code = store_init_value (decl, init, cleanups, flags);
6869
6870 if (DECL_INITIAL (decl)
6871 && TREE_CODE (DECL_INITIAL (decl)) == CONSTRUCTOR
6872 && !vec_safe_is_empty (CONSTRUCTOR_ELTS (DECL_INITIAL (decl))))
6873 {
6874 tree elt = CONSTRUCTOR_ELTS (DECL_INITIAL (decl))->last ().value;
6875 if (TREE_CODE (TREE_TYPE (elt)) == ARRAY_TYPE
6876 && TYPE_SIZE (TREE_TYPE (elt)) == NULL_TREE)
6877 cp_complete_array_type (&TREE_TYPE (elt), elt, false);
6878 }
6879
6880 if (pedantic && TREE_CODE (type) == ARRAY_TYPE
6881 && DECL_INITIAL (decl)
6882 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
6883 && PAREN_STRING_LITERAL_P (DECL_INITIAL (decl)))
6884 warning_at (cp_expr_loc_or_loc (DECL_INITIAL (decl),
6885 DECL_SOURCE_LOCATION (decl)),
6886 0, "array %qD initialized by parenthesized "
6887 "string literal %qE",
6888 decl, DECL_INITIAL (decl));
6889 init = NULL_TREE;
6890 }
6891 }
6892 else
6893 {
6894 if (CLASS_TYPE_P (core_type = strip_array_types (type))
6895 && (CLASSTYPE_READONLY_FIELDS_NEED_INIT (core_type)
6896 || CLASSTYPE_REF_FIELDS_NEED_INIT (core_type)))
6897 diagnose_uninitialized_cst_or_ref_member (core_type, /*using_new=*/false,
6898 /*complain=*/true);
6899
6900 check_for_uninitialized_const_var (decl, /*constexpr_context_p=*/false,
6901 tf_warning_or_error);
6902 }
6903
6904 if (init && init != error_mark_node)
6905 init_code = build2 (INIT_EXPR, type, decl, init);
6906
6907 if (init_code)
6908 {
6909 /* We might have set these in cp_finish_decl. */
6910 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl) = false;
6911 TREE_CONSTANT (decl) = false;
6912 }
6913
6914 if (init_code
6915 && DECL_IN_AGGR_P (decl)
6916 && DECL_INITIALIZED_IN_CLASS_P (decl))
6917 {
6918 static int explained = 0;
6919
6920 if (cxx_dialect < cxx11)
6921 error ("initializer invalid for static member with constructor");
6922 else if (cxx_dialect < cxx17)
6923 error ("non-constant in-class initialization invalid for static "
6924 "member %qD", decl);
6925 else
6926 error ("non-constant in-class initialization invalid for non-inline "
6927 "static member %qD", decl);
6928 if (!explained)
6929 {
6930 inform (input_location,
6931 "(an out of class initialization is required)");
6932 explained = 1;
6933 }
6934 return NULL_TREE;
6935 }
6936
6937 return init_code;
6938 }
6939
6940 /* If DECL is not a local variable, give it RTL. */
6941
6942 static void
make_rtl_for_nonlocal_decl(tree decl,tree init,const char * asmspec)6943 make_rtl_for_nonlocal_decl (tree decl, tree init, const char* asmspec)
6944 {
6945 int toplev = toplevel_bindings_p ();
6946 int defer_p;
6947
6948 /* Set the DECL_ASSEMBLER_NAME for the object. */
6949 if (asmspec)
6950 {
6951 /* The `register' keyword, when used together with an
6952 asm-specification, indicates that the variable should be
6953 placed in a particular register. */
6954 if (VAR_P (decl) && DECL_REGISTER (decl))
6955 {
6956 set_user_assembler_name (decl, asmspec);
6957 DECL_HARD_REGISTER (decl) = 1;
6958 }
6959 else
6960 {
6961 if (TREE_CODE (decl) == FUNCTION_DECL
6962 && fndecl_built_in_p (decl, BUILT_IN_NORMAL))
6963 set_builtin_user_assembler_name (decl, asmspec);
6964 set_user_assembler_name (decl, asmspec);
6965 }
6966 }
6967
6968 /* Handle non-variables up front. */
6969 if (!VAR_P (decl))
6970 {
6971 rest_of_decl_compilation (decl, toplev, at_eof);
6972 return;
6973 }
6974
6975 /* If we see a class member here, it should be a static data
6976 member. */
6977 if (DECL_LANG_SPECIFIC (decl) && DECL_IN_AGGR_P (decl))
6978 {
6979 gcc_assert (TREE_STATIC (decl));
6980 /* An in-class declaration of a static data member should be
6981 external; it is only a declaration, and not a definition. */
6982 if (init == NULL_TREE)
6983 gcc_assert (DECL_EXTERNAL (decl)
6984 || !TREE_PUBLIC (decl));
6985 }
6986
6987 /* We don't create any RTL for local variables. */
6988 if (DECL_FUNCTION_SCOPE_P (decl) && !TREE_STATIC (decl))
6989 return;
6990
6991 /* We defer emission of local statics until the corresponding
6992 DECL_EXPR is expanded. But with constexpr its function might never
6993 be expanded, so go ahead and tell cgraph about the variable now. */
6994 defer_p = ((DECL_FUNCTION_SCOPE_P (decl)
6995 && !var_in_maybe_constexpr_fn (decl))
6996 || DECL_VIRTUAL_P (decl));
6997
6998 /* Defer template instantiations. */
6999 if (DECL_LANG_SPECIFIC (decl)
7000 && DECL_IMPLICIT_INSTANTIATION (decl))
7001 defer_p = 1;
7002
7003 /* If we're not deferring, go ahead and assemble the variable. */
7004 if (!defer_p)
7005 rest_of_decl_compilation (decl, toplev, at_eof);
7006 }
7007
7008 /* walk_tree helper for wrap_temporary_cleanups, below. */
7009
7010 static tree
wrap_cleanups_r(tree * stmt_p,int * walk_subtrees,void * data)7011 wrap_cleanups_r (tree *stmt_p, int *walk_subtrees, void *data)
7012 {
7013 /* Stop at types or full-expression boundaries. */
7014 if (TYPE_P (*stmt_p)
7015 || TREE_CODE (*stmt_p) == CLEANUP_POINT_EXPR)
7016 {
7017 *walk_subtrees = 0;
7018 return NULL_TREE;
7019 }
7020
7021 if (TREE_CODE (*stmt_p) == TARGET_EXPR)
7022 {
7023 tree guard = (tree)data;
7024 tree tcleanup = TARGET_EXPR_CLEANUP (*stmt_p);
7025
7026 tcleanup = build2 (TRY_CATCH_EXPR, void_type_node, tcleanup, guard);
7027 /* Tell honor_protect_cleanup_actions to handle this as a separate
7028 cleanup. */
7029 TRY_CATCH_IS_CLEANUP (tcleanup) = 1;
7030
7031 TARGET_EXPR_CLEANUP (*stmt_p) = tcleanup;
7032 }
7033
7034 return NULL_TREE;
7035 }
7036
7037 /* We're initializing a local variable which has a cleanup GUARD. If there
7038 are any temporaries used in the initializer INIT of this variable, we
7039 need to wrap their cleanups with TRY_CATCH_EXPR (, GUARD) so that the
7040 variable will be cleaned up properly if one of them throws.
7041
7042 Unfortunately, there's no way to express this properly in terms of
7043 nesting, as the regions for the temporaries overlap the region for the
7044 variable itself; if there are two temporaries, the variable needs to be
7045 the first thing destroyed if either of them throws. However, we only
7046 want to run the variable's cleanup if it actually got constructed. So
7047 we need to guard the temporary cleanups with the variable's cleanup if
7048 they are run on the normal path, but not if they are run on the
7049 exceptional path. We implement this by telling
7050 honor_protect_cleanup_actions to strip the variable cleanup from the
7051 exceptional path. */
7052
7053 static void
wrap_temporary_cleanups(tree init,tree guard)7054 wrap_temporary_cleanups (tree init, tree guard)
7055 {
7056 cp_walk_tree_without_duplicates (&init, wrap_cleanups_r, (void *)guard);
7057 }
7058
7059 /* Generate code to initialize DECL (a local variable). */
7060
7061 static void
initialize_local_var(tree decl,tree init)7062 initialize_local_var (tree decl, tree init)
7063 {
7064 tree type = TREE_TYPE (decl);
7065 tree cleanup;
7066 int already_used;
7067
7068 gcc_assert (VAR_P (decl)
7069 || TREE_CODE (decl) == RESULT_DECL);
7070 gcc_assert (!TREE_STATIC (decl));
7071
7072 if (DECL_SIZE (decl) == NULL_TREE)
7073 {
7074 /* If we used it already as memory, it must stay in memory. */
7075 DECL_INITIAL (decl) = NULL_TREE;
7076 TREE_ADDRESSABLE (decl) = TREE_USED (decl);
7077 return;
7078 }
7079
7080 if (type == error_mark_node)
7081 return;
7082
7083 /* Compute and store the initial value. */
7084 already_used = TREE_USED (decl) || TREE_USED (type);
7085 if (TREE_USED (type))
7086 DECL_READ_P (decl) = 1;
7087
7088 /* Generate a cleanup, if necessary. */
7089 cleanup = cxx_maybe_build_cleanup (decl, tf_warning_or_error);
7090
7091 /* Perform the initialization. */
7092 if (init)
7093 {
7094 tree rinit = (TREE_CODE (init) == INIT_EXPR
7095 ? TREE_OPERAND (init, 1) : NULL_TREE);
7096 if (rinit && !TREE_SIDE_EFFECTS (rinit))
7097 {
7098 /* Stick simple initializers in DECL_INITIAL so that
7099 -Wno-init-self works (c++/34772). */
7100 gcc_assert (TREE_OPERAND (init, 0) == decl);
7101 DECL_INITIAL (decl) = rinit;
7102
7103 if (warn_init_self && TYPE_REF_P (type))
7104 {
7105 STRIP_NOPS (rinit);
7106 if (rinit == decl)
7107 warning_at (DECL_SOURCE_LOCATION (decl),
7108 OPT_Winit_self,
7109 "reference %qD is initialized with itself", decl);
7110 }
7111 }
7112 else
7113 {
7114 int saved_stmts_are_full_exprs_p;
7115
7116 /* If we're only initializing a single object, guard the
7117 destructors of any temporaries used in its initializer with
7118 its destructor. This isn't right for arrays because each
7119 element initialization is a full-expression. */
7120 if (cleanup && TREE_CODE (type) != ARRAY_TYPE)
7121 wrap_temporary_cleanups (init, cleanup);
7122
7123 gcc_assert (building_stmt_list_p ());
7124 saved_stmts_are_full_exprs_p = stmts_are_full_exprs_p ();
7125 current_stmt_tree ()->stmts_are_full_exprs_p = 1;
7126 finish_expr_stmt (init);
7127 current_stmt_tree ()->stmts_are_full_exprs_p =
7128 saved_stmts_are_full_exprs_p;
7129 }
7130 }
7131
7132 /* Set this to 0 so we can tell whether an aggregate which was
7133 initialized was ever used. Don't do this if it has a
7134 destructor, so we don't complain about the 'resource
7135 allocation is initialization' idiom. Now set
7136 attribute((unused)) on types so decls of that type will be
7137 marked used. (see TREE_USED, above.) */
7138 if (TYPE_NEEDS_CONSTRUCTING (type)
7139 && ! already_used
7140 && TYPE_HAS_TRIVIAL_DESTRUCTOR (type)
7141 && DECL_NAME (decl))
7142 TREE_USED (decl) = 0;
7143 else if (already_used)
7144 TREE_USED (decl) = 1;
7145
7146 if (cleanup)
7147 finish_decl_cleanup (decl, cleanup);
7148 }
7149
7150 /* DECL is a VAR_DECL for a compiler-generated variable with static
7151 storage duration (like a virtual table) whose initializer is a
7152 compile-time constant. Initialize the variable and provide it to the
7153 back end. */
7154
7155 void
initialize_artificial_var(tree decl,vec<constructor_elt,va_gc> * v)7156 initialize_artificial_var (tree decl, vec<constructor_elt, va_gc> *v)
7157 {
7158 tree init;
7159 gcc_assert (DECL_ARTIFICIAL (decl));
7160 init = build_constructor (TREE_TYPE (decl), v);
7161 gcc_assert (TREE_CODE (init) == CONSTRUCTOR);
7162 DECL_INITIAL (decl) = init;
7163 DECL_INITIALIZED_P (decl) = 1;
7164 /* Mark the decl as constexpr so that we can access its content
7165 at compile time. */
7166 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl) = true;
7167 DECL_DECLARED_CONSTEXPR_P (decl) = true;
7168 determine_visibility (decl);
7169 layout_var_decl (decl);
7170 maybe_commonize_var (decl);
7171 make_rtl_for_nonlocal_decl (decl, init, /*asmspec=*/NULL);
7172 }
7173
7174 /* INIT is the initializer for a variable, as represented by the
7175 parser. Returns true iff INIT is value-dependent. */
7176
7177 static bool
value_dependent_init_p(tree init)7178 value_dependent_init_p (tree init)
7179 {
7180 if (TREE_CODE (init) == TREE_LIST)
7181 /* A parenthesized initializer, e.g.: int i (3, 2); ? */
7182 return any_value_dependent_elements_p (init);
7183 else if (TREE_CODE (init) == CONSTRUCTOR)
7184 /* A brace-enclosed initializer, e.g.: int i = { 3 }; ? */
7185 {
7186 if (dependent_type_p (TREE_TYPE (init)))
7187 return true;
7188
7189 vec<constructor_elt, va_gc> *elts;
7190 size_t nelts;
7191 size_t i;
7192
7193 elts = CONSTRUCTOR_ELTS (init);
7194 nelts = vec_safe_length (elts);
7195 for (i = 0; i < nelts; ++i)
7196 if (value_dependent_init_p ((*elts)[i].value))
7197 return true;
7198 }
7199 else
7200 /* It must be a simple expression, e.g., int i = 3; */
7201 return value_dependent_expression_p (init);
7202
7203 return false;
7204 }
7205
7206 // Returns true if a DECL is VAR_DECL with the concept specifier.
7207 static inline bool
is_concept_var(tree decl)7208 is_concept_var (tree decl)
7209 {
7210 return (VAR_P (decl)
7211 // Not all variables have DECL_LANG_SPECIFIC.
7212 && DECL_LANG_SPECIFIC (decl)
7213 && DECL_DECLARED_CONCEPT_P (decl));
7214 }
7215
7216 /* A helper function to be called via walk_tree. If any label exists
7217 under *TP, it is (going to be) forced. Set has_forced_label_in_static. */
7218
7219 static tree
notice_forced_label_r(tree * tp,int * walk_subtrees,void *)7220 notice_forced_label_r (tree *tp, int *walk_subtrees, void *)
7221 {
7222 if (TYPE_P (*tp))
7223 *walk_subtrees = 0;
7224 if (TREE_CODE (*tp) == LABEL_DECL)
7225 cfun->has_forced_label_in_static = 1;
7226 return NULL_TREE;
7227 }
7228
7229 /* Return true if DECL has either a trivial destructor, or for C++2A
7230 is constexpr and has a constexpr destructor. */
7231
7232 static bool
decl_maybe_constant_destruction(tree decl,tree type)7233 decl_maybe_constant_destruction (tree decl, tree type)
7234 {
7235 return (TYPE_HAS_TRIVIAL_DESTRUCTOR (type)
7236 || (cxx_dialect >= cxx2a
7237 && VAR_P (decl)
7238 && DECL_DECLARED_CONSTEXPR_P (decl)
7239 && type_has_constexpr_destructor (strip_array_types (type))));
7240 }
7241
7242 static tree declare_simd_adjust_this (tree *, int *, void *);
7243
7244 /* Helper function of omp_declare_variant_finalize. Finalize one
7245 "omp declare variant base" attribute. Return true if it should be
7246 removed. */
7247
7248 static bool
omp_declare_variant_finalize_one(tree decl,tree attr)7249 omp_declare_variant_finalize_one (tree decl, tree attr)
7250 {
7251 if (TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE)
7252 {
7253 walk_tree (&TREE_VALUE (TREE_VALUE (attr)), declare_simd_adjust_this,
7254 DECL_ARGUMENTS (decl), NULL);
7255 walk_tree (&TREE_PURPOSE (TREE_VALUE (attr)), declare_simd_adjust_this,
7256 DECL_ARGUMENTS (decl), NULL);
7257 }
7258
7259 tree ctx = TREE_VALUE (TREE_VALUE (attr));
7260 tree simd = omp_get_context_selector (ctx, "construct", "simd");
7261 if (simd)
7262 {
7263 TREE_VALUE (simd)
7264 = c_omp_declare_simd_clauses_to_numbers (DECL_ARGUMENTS (decl),
7265 TREE_VALUE (simd));
7266 /* FIXME, adjusting simd args unimplemented. */
7267 return true;
7268 }
7269
7270 tree chain = TREE_CHAIN (TREE_VALUE (attr));
7271 location_t varid_loc
7272 = cp_expr_loc_or_input_loc (TREE_PURPOSE (TREE_CHAIN (chain)));
7273 location_t match_loc = cp_expr_loc_or_input_loc (TREE_PURPOSE (chain));
7274 cp_id_kind idk = (cp_id_kind) tree_to_uhwi (TREE_VALUE (chain));
7275 tree variant = TREE_PURPOSE (TREE_VALUE (attr));
7276
7277 location_t save_loc = input_location;
7278 input_location = varid_loc;
7279
7280 releasing_vec args;
7281 tree parm = DECL_ARGUMENTS (decl);
7282 if (TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE)
7283 parm = DECL_CHAIN (parm);
7284 for (; parm; parm = DECL_CHAIN (parm))
7285 if (type_dependent_expression_p (parm))
7286 vec_safe_push (args, build_constructor (TREE_TYPE (parm), NULL));
7287 else if (MAYBE_CLASS_TYPE_P (TREE_TYPE (parm)))
7288 vec_safe_push (args, build_local_temp (TREE_TYPE (parm)));
7289 else
7290 vec_safe_push (args, build_zero_cst (TREE_TYPE (parm)));
7291
7292 bool koenig_p = false;
7293 if (idk == CP_ID_KIND_UNQUALIFIED || idk == CP_ID_KIND_TEMPLATE_ID)
7294 {
7295 if (identifier_p (variant)
7296 /* In C++2A, we may need to perform ADL for a template
7297 name. */
7298 || (TREE_CODE (variant) == TEMPLATE_ID_EXPR
7299 && identifier_p (TREE_OPERAND (variant, 0))))
7300 {
7301 if (!args->is_empty ())
7302 {
7303 koenig_p = true;
7304 if (!any_type_dependent_arguments_p (args))
7305 variant = perform_koenig_lookup (variant, args,
7306 tf_warning_or_error);
7307 }
7308 else
7309 variant = unqualified_fn_lookup_error (variant);
7310 }
7311 else if (!args->is_empty () && is_overloaded_fn (variant))
7312 {
7313 tree fn = get_first_fn (variant);
7314 fn = STRIP_TEMPLATE (fn);
7315 if (!((TREE_CODE (fn) == USING_DECL && DECL_DEPENDENT_P (fn))
7316 || DECL_FUNCTION_MEMBER_P (fn)
7317 || DECL_LOCAL_FUNCTION_P (fn)))
7318 {
7319 koenig_p = true;
7320 if (!any_type_dependent_arguments_p (args))
7321 variant = perform_koenig_lookup (variant, args,
7322 tf_warning_or_error);
7323 }
7324 }
7325 }
7326
7327 if (idk == CP_ID_KIND_QUALIFIED)
7328 variant = finish_call_expr (variant, &args, /*disallow_virtual=*/true,
7329 koenig_p, tf_warning_or_error);
7330 else
7331 variant = finish_call_expr (variant, &args, /*disallow_virtual=*/false,
7332 koenig_p, tf_warning_or_error);
7333 if (variant == error_mark_node && !processing_template_decl)
7334 return true;
7335
7336 variant = cp_get_callee_fndecl_nofold (variant);
7337 input_location = save_loc;
7338
7339 if (variant)
7340 {
7341 const char *varname = IDENTIFIER_POINTER (DECL_NAME (variant));
7342 if (!comptypes (TREE_TYPE (decl), TREE_TYPE (variant), 0))
7343 {
7344 error_at (varid_loc, "variant %qD and base %qD have incompatible "
7345 "types", variant, decl);
7346 return true;
7347 }
7348 if (fndecl_built_in_p (variant)
7349 && (strncmp (varname, "__builtin_", strlen ("__builtin_")) == 0
7350 || strncmp (varname, "__sync_", strlen ("__sync_")) == 0
7351 || strncmp (varname, "__atomic_", strlen ("__atomic_")) == 0))
7352 {
7353 error_at (varid_loc, "variant %qD is a built-in", variant);
7354 return true;
7355 }
7356 else
7357 {
7358 tree construct = omp_get_context_selector (ctx, "construct", NULL);
7359 c_omp_mark_declare_variant (match_loc, variant, construct);
7360 if (!omp_context_selector_matches (ctx))
7361 return true;
7362 TREE_PURPOSE (TREE_VALUE (attr)) = variant;
7363 }
7364 }
7365 else if (!processing_template_decl)
7366 {
7367 error_at (varid_loc, "could not find variant declaration");
7368 return true;
7369 }
7370
7371 return false;
7372 }
7373
7374 /* Helper function, finish up "omp declare variant base" attribute
7375 now that there is a DECL. ATTR is the first "omp declare variant base"
7376 attribute. */
7377
7378 void
omp_declare_variant_finalize(tree decl,tree attr)7379 omp_declare_variant_finalize (tree decl, tree attr)
7380 {
7381 size_t attr_len = strlen ("omp declare variant base");
7382 tree *list = &DECL_ATTRIBUTES (decl);
7383 bool remove_all = false;
7384 location_t match_loc = DECL_SOURCE_LOCATION (decl);
7385 if (TREE_CHAIN (TREE_VALUE (attr))
7386 && TREE_PURPOSE (TREE_CHAIN (TREE_VALUE (attr)))
7387 && EXPR_HAS_LOCATION (TREE_PURPOSE (TREE_CHAIN (TREE_VALUE (attr)))))
7388 match_loc = EXPR_LOCATION (TREE_PURPOSE (TREE_CHAIN (TREE_VALUE (attr))));
7389 if (DECL_CONSTRUCTOR_P (decl))
7390 {
7391 error_at (match_loc, "%<declare variant%> on constructor %qD", decl);
7392 remove_all = true;
7393 }
7394 else if (DECL_DESTRUCTOR_P (decl))
7395 {
7396 error_at (match_loc, "%<declare variant%> on destructor %qD", decl);
7397 remove_all = true;
7398 }
7399 else if (DECL_DEFAULTED_FN (decl))
7400 {
7401 error_at (match_loc, "%<declare variant%> on defaulted %qD", decl);
7402 remove_all = true;
7403 }
7404 else if (DECL_DELETED_FN (decl))
7405 {
7406 error_at (match_loc, "%<declare variant%> on deleted %qD", decl);
7407 remove_all = true;
7408 }
7409 else if (DECL_VIRTUAL_P (decl))
7410 {
7411 error_at (match_loc, "%<declare variant%> on virtual %qD", decl);
7412 remove_all = true;
7413 }
7414 /* This loop is like private_lookup_attribute, except that it works
7415 with tree * rather than tree, as we might want to remove the
7416 attributes that are diagnosed as errorneous. */
7417 while (*list)
7418 {
7419 tree attr = get_attribute_name (*list);
7420 size_t ident_len = IDENTIFIER_LENGTH (attr);
7421 if (cmp_attribs ("omp declare variant base", attr_len,
7422 IDENTIFIER_POINTER (attr), ident_len))
7423 {
7424 if (remove_all || omp_declare_variant_finalize_one (decl, *list))
7425 {
7426 *list = TREE_CHAIN (*list);
7427 continue;
7428 }
7429 }
7430 list = &TREE_CHAIN (*list);
7431 }
7432 }
7433
7434 /* Finish processing of a declaration;
7435 install its line number and initial value.
7436 If the length of an array type is not known before,
7437 it must be determined now, from the initial value, or it is an error.
7438
7439 INIT is the initializer (if any) for DECL. If INIT_CONST_EXPR_P is
7440 true, then INIT is an integral constant expression.
7441
7442 FLAGS is LOOKUP_ONLYCONVERTING if the = init syntax was used, else 0
7443 if the (init) syntax was used. */
7444
7445 void
cp_finish_decl(tree decl,tree init,bool init_const_expr_p,tree asmspec_tree,int flags)7446 cp_finish_decl (tree decl, tree init, bool init_const_expr_p,
7447 tree asmspec_tree, int flags)
7448 {
7449 tree type;
7450 vec<tree, va_gc> *cleanups = NULL;
7451 const char *asmspec = NULL;
7452 int was_readonly = 0;
7453 bool var_definition_p = false;
7454 tree auto_node;
7455
7456 if (decl == error_mark_node)
7457 return;
7458 else if (! decl)
7459 {
7460 if (init)
7461 error ("assignment (not initialization) in declaration");
7462 return;
7463 }
7464
7465 gcc_assert (TREE_CODE (decl) != RESULT_DECL);
7466 /* Parameters are handled by store_parm_decls, not cp_finish_decl. */
7467 gcc_assert (TREE_CODE (decl) != PARM_DECL);
7468
7469 type = TREE_TYPE (decl);
7470 if (type == error_mark_node)
7471 return;
7472
7473 /* Warn about register storage specifiers except when in GNU global
7474 or local register variable extension. */
7475 if (VAR_P (decl) && DECL_REGISTER (decl) && asmspec_tree == NULL_TREE)
7476 {
7477 if (cxx_dialect >= cxx17)
7478 pedwarn (DECL_SOURCE_LOCATION (decl), OPT_Wregister,
7479 "ISO C++17 does not allow %<register%> storage "
7480 "class specifier");
7481 else
7482 warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wregister,
7483 "%<register%> storage class specifier used");
7484 }
7485
7486 /* If a name was specified, get the string. */
7487 if (at_namespace_scope_p ())
7488 asmspec_tree = maybe_apply_renaming_pragma (decl, asmspec_tree);
7489 if (asmspec_tree && asmspec_tree != error_mark_node)
7490 asmspec = TREE_STRING_POINTER (asmspec_tree);
7491
7492 bool in_class_decl
7493 = (current_class_type
7494 && CP_DECL_CONTEXT (decl) == current_class_type
7495 && TYPE_BEING_DEFINED (current_class_type)
7496 && !CLASSTYPE_TEMPLATE_INSTANTIATION (current_class_type));
7497
7498 if (in_class_decl
7499 && (DECL_INITIAL (decl) || init))
7500 DECL_INITIALIZED_IN_CLASS_P (decl) = 1;
7501
7502 /* Do auto deduction unless decl is a function or an uninstantiated
7503 template specialization. */
7504 if (TREE_CODE (decl) != FUNCTION_DECL
7505 && !(init == NULL_TREE
7506 && DECL_LANG_SPECIFIC (decl)
7507 && DECL_TEMPLATE_INSTANTIATION (decl)
7508 && !DECL_TEMPLATE_INSTANTIATED (decl))
7509 && (auto_node = type_uses_auto (type)))
7510 {
7511 tree d_init;
7512 if (init == NULL_TREE)
7513 gcc_assert (CLASS_PLACEHOLDER_TEMPLATE (auto_node));
7514 d_init = init;
7515 if (d_init)
7516 {
7517 if (TREE_CODE (d_init) == TREE_LIST
7518 && !CLASS_PLACEHOLDER_TEMPLATE (auto_node))
7519 d_init = build_x_compound_expr_from_list (d_init, ELK_INIT,
7520 tf_warning_or_error);
7521 d_init = resolve_nondeduced_context (d_init, tf_warning_or_error);
7522 }
7523 enum auto_deduction_context adc = adc_variable_type;
7524 if (VAR_P (decl) && DECL_DECOMPOSITION_P (decl))
7525 adc = adc_decomp_type;
7526 type = TREE_TYPE (decl) = do_auto_deduction (type, d_init, auto_node,
7527 tf_warning_or_error, adc,
7528 NULL_TREE, flags);
7529 if (type == error_mark_node)
7530 return;
7531 if (TREE_CODE (type) == FUNCTION_TYPE)
7532 {
7533 error ("initializer for %<decltype(auto) %D%> has function type; "
7534 "did you forget the %<()%>?", decl);
7535 TREE_TYPE (decl) = error_mark_node;
7536 return;
7537 }
7538 cp_apply_type_quals_to_decl (cp_type_quals (type), decl);
7539 }
7540
7541 if (ensure_literal_type_for_constexpr_object (decl) == error_mark_node)
7542 {
7543 DECL_DECLARED_CONSTEXPR_P (decl) = 0;
7544 if (VAR_P (decl) && DECL_CLASS_SCOPE_P (decl))
7545 {
7546 init = NULL_TREE;
7547 DECL_EXTERNAL (decl) = 1;
7548 }
7549 }
7550
7551 if (VAR_P (decl)
7552 && DECL_CLASS_SCOPE_P (decl)
7553 && verify_type_context (DECL_SOURCE_LOCATION (decl),
7554 TCTX_STATIC_STORAGE, type)
7555 && DECL_INITIALIZED_IN_CLASS_P (decl))
7556 check_static_variable_definition (decl, type);
7557
7558 if (init && TREE_CODE (decl) == FUNCTION_DECL)
7559 {
7560 tree clone;
7561 if (init == ridpointers[(int)RID_DELETE])
7562 {
7563 /* FIXME check this is 1st decl. */
7564 DECL_DELETED_FN (decl) = 1;
7565 DECL_DECLARED_INLINE_P (decl) = 1;
7566 DECL_INITIAL (decl) = error_mark_node;
7567 FOR_EACH_CLONE (clone, decl)
7568 {
7569 DECL_DELETED_FN (clone) = 1;
7570 DECL_DECLARED_INLINE_P (clone) = 1;
7571 DECL_INITIAL (clone) = error_mark_node;
7572 }
7573 init = NULL_TREE;
7574 }
7575 else if (init == ridpointers[(int)RID_DEFAULT])
7576 {
7577 if (defaultable_fn_check (decl))
7578 DECL_DEFAULTED_FN (decl) = 1;
7579 else
7580 DECL_INITIAL (decl) = NULL_TREE;
7581 }
7582 }
7583
7584 if (init && VAR_P (decl))
7585 {
7586 DECL_NONTRIVIALLY_INITIALIZED_P (decl) = 1;
7587 /* If DECL is a reference, then we want to know whether init is a
7588 reference constant; init_const_expr_p as passed tells us whether
7589 it's an rvalue constant. */
7590 if (TYPE_REF_P (type))
7591 init_const_expr_p = potential_constant_expression (init);
7592 if (init_const_expr_p)
7593 {
7594 /* Set these flags now for templates. We'll update the flags in
7595 store_init_value for instantiations. */
7596 DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl) = 1;
7597 if (decl_maybe_constant_var_p (decl)
7598 /* FIXME setting TREE_CONSTANT on refs breaks the back end. */
7599 && !TYPE_REF_P (type))
7600 TREE_CONSTANT (decl) = 1;
7601 }
7602 }
7603
7604 if (flag_openmp
7605 && TREE_CODE (decl) == FUNCTION_DECL
7606 /* #pragma omp declare variant on methods handled in finish_struct
7607 instead. */
7608 && (!DECL_NONSTATIC_MEMBER_FUNCTION_P (decl)
7609 || COMPLETE_TYPE_P (DECL_CONTEXT (decl))))
7610 if (tree attr = lookup_attribute ("omp declare variant base",
7611 DECL_ATTRIBUTES (decl)))
7612 omp_declare_variant_finalize (decl, attr);
7613
7614 if (processing_template_decl)
7615 {
7616 bool type_dependent_p;
7617
7618 /* Add this declaration to the statement-tree. */
7619 if (at_function_scope_p ())
7620 add_decl_expr (decl);
7621
7622 type_dependent_p = dependent_type_p (type);
7623
7624 if (check_for_bare_parameter_packs (init))
7625 {
7626 init = NULL_TREE;
7627 DECL_INITIAL (decl) = NULL_TREE;
7628 }
7629
7630 /* Handle `constinit' on variable templates. */
7631 if (flags & LOOKUP_CONSTINIT)
7632 TINFO_VAR_DECLARED_CONSTINIT (DECL_TEMPLATE_INFO (decl)) = true;
7633
7634 /* Generally, initializers in templates are expanded when the
7635 template is instantiated. But, if DECL is a variable constant
7636 then it can be used in future constant expressions, so its value
7637 must be available. */
7638
7639 bool dep_init = false;
7640
7641 if (!VAR_P (decl) || type_dependent_p)
7642 /* We can't do anything if the decl has dependent type. */;
7643 else if (!init && is_concept_var (decl))
7644 {
7645 error ("variable concept has no initializer");
7646 init = boolean_true_node;
7647 }
7648 else if (init
7649 && init_const_expr_p
7650 && !TYPE_REF_P (type)
7651 && decl_maybe_constant_var_p (decl)
7652 && !(dep_init = value_dependent_init_p (init)))
7653 {
7654 /* This variable seems to be a non-dependent constant, so process
7655 its initializer. If check_initializer returns non-null the
7656 initialization wasn't constant after all. */
7657 tree init_code;
7658 cleanups = make_tree_vector ();
7659 init_code = check_initializer (decl, init, flags, &cleanups);
7660 if (init_code == NULL_TREE)
7661 init = NULL_TREE;
7662 release_tree_vector (cleanups);
7663 }
7664 else
7665 {
7666 gcc_assert (!DECL_PRETTY_FUNCTION_P (decl));
7667 /* Deduce array size even if the initializer is dependent. */
7668 maybe_deduce_size_from_array_init (decl, init);
7669 /* And complain about multiple initializers. */
7670 if (init && TREE_CODE (init) == TREE_LIST && TREE_CHAIN (init)
7671 && !MAYBE_CLASS_TYPE_P (type))
7672 init = build_x_compound_expr_from_list (init, ELK_INIT,
7673 tf_warning_or_error);
7674 }
7675
7676 if (init)
7677 DECL_INITIAL (decl) = init;
7678
7679 if (dep_init)
7680 {
7681 retrofit_lang_decl (decl);
7682 SET_DECL_DEPENDENT_INIT_P (decl, true);
7683 }
7684
7685 if (VAR_P (decl) && DECL_REGISTER (decl) && asmspec)
7686 {
7687 set_user_assembler_name (decl, asmspec);
7688 DECL_HARD_REGISTER (decl) = 1;
7689 }
7690 return;
7691 }
7692
7693 /* Just store non-static data member initializers for later. */
7694 if (init && TREE_CODE (decl) == FIELD_DECL)
7695 DECL_INITIAL (decl) = init;
7696
7697 /* Take care of TYPE_DECLs up front. */
7698 if (TREE_CODE (decl) == TYPE_DECL)
7699 {
7700 if (type != error_mark_node
7701 && MAYBE_CLASS_TYPE_P (type) && DECL_NAME (decl))
7702 {
7703 if (TREE_TYPE (DECL_NAME (decl)) && TREE_TYPE (decl) != type)
7704 warning (0, "shadowing previous type declaration of %q#D", decl);
7705 set_identifier_type_value (DECL_NAME (decl), decl);
7706 }
7707
7708 /* If we have installed this as the canonical typedef for this
7709 type, and that type has not been defined yet, delay emitting
7710 the debug information for it, as we will emit it later. */
7711 if (TYPE_MAIN_DECL (TREE_TYPE (decl)) == decl
7712 && !COMPLETE_TYPE_P (TREE_TYPE (decl)))
7713 TYPE_DECL_SUPPRESS_DEBUG (decl) = 1;
7714
7715 rest_of_decl_compilation (decl, DECL_FILE_SCOPE_P (decl),
7716 at_eof);
7717 return;
7718 }
7719
7720 /* A reference will be modified here, as it is initialized. */
7721 if (! DECL_EXTERNAL (decl)
7722 && TREE_READONLY (decl)
7723 && TYPE_REF_P (type))
7724 {
7725 was_readonly = 1;
7726 TREE_READONLY (decl) = 0;
7727 }
7728
7729 /* This needs to happen before extend_ref_init_temps. */
7730 if (VAR_OR_FUNCTION_DECL_P (decl))
7731 {
7732 if (VAR_P (decl))
7733 maybe_commonize_var (decl);
7734 determine_visibility (decl);
7735 }
7736
7737 if (VAR_P (decl))
7738 {
7739 duration_kind dk = decl_storage_duration (decl);
7740 /* [dcl.constinit]/1 "The constinit specifier shall be applied
7741 only to a declaration of a variable with static or thread storage
7742 duration." */
7743 if ((flags & LOOKUP_CONSTINIT)
7744 && !(dk == dk_thread || dk == dk_static))
7745 {
7746 error_at (DECL_SOURCE_LOCATION (decl),
7747 "%<constinit%> can only be applied to a variable with "
7748 "static or thread storage duration");
7749 return;
7750 }
7751
7752 /* If this is a local variable that will need a mangled name,
7753 register it now. We must do this before processing the
7754 initializer for the variable, since the initialization might
7755 require a guard variable, and since the mangled name of the
7756 guard variable will depend on the mangled name of this
7757 variable. */
7758 if (DECL_FUNCTION_SCOPE_P (decl)
7759 && TREE_STATIC (decl)
7760 && !DECL_ARTIFICIAL (decl))
7761 {
7762 /* The variable holding an anonymous union will have had its
7763 discriminator set in finish_anon_union, after which it's
7764 NAME will have been cleared. */
7765 if (DECL_NAME (decl))
7766 determine_local_discriminator (decl);
7767 /* Normally has_forced_label_in_static is set during GIMPLE
7768 lowering, but [cd]tors are never actually compiled directly.
7769 We need to set this early so we can deal with the label
7770 address extension. */
7771 if ((DECL_CONSTRUCTOR_P (current_function_decl)
7772 || DECL_DESTRUCTOR_P (current_function_decl))
7773 && init)
7774 {
7775 walk_tree (&init, notice_forced_label_r, NULL, NULL);
7776 add_local_decl (cfun, decl);
7777 }
7778 /* And make sure it's in the symbol table for
7779 c_parse_final_cleanups to find. */
7780 varpool_node::get_create (decl);
7781 }
7782
7783 /* Convert the initializer to the type of DECL, if we have not
7784 already initialized DECL. */
7785 if (!DECL_INITIALIZED_P (decl)
7786 /* If !DECL_EXTERNAL then DECL is being defined. In the
7787 case of a static data member initialized inside the
7788 class-specifier, there can be an initializer even if DECL
7789 is *not* defined. */
7790 && (!DECL_EXTERNAL (decl) || init))
7791 {
7792 cleanups = make_tree_vector ();
7793 init = check_initializer (decl, init, flags, &cleanups);
7794
7795 /* Handle:
7796
7797 [dcl.init]
7798
7799 The memory occupied by any object of static storage
7800 duration is zero-initialized at program startup before
7801 any other initialization takes place.
7802
7803 We cannot create an appropriate initializer until after
7804 the type of DECL is finalized. If DECL_INITIAL is set,
7805 then the DECL is statically initialized, and any
7806 necessary zero-initialization has already been performed. */
7807 if (TREE_STATIC (decl) && !DECL_INITIAL (decl))
7808 DECL_INITIAL (decl) = build_zero_init (TREE_TYPE (decl),
7809 /*nelts=*/NULL_TREE,
7810 /*static_storage_p=*/true);
7811 /* Remember that the initialization for this variable has
7812 taken place. */
7813 DECL_INITIALIZED_P (decl) = 1;
7814 /* This declaration is the definition of this variable,
7815 unless we are initializing a static data member within
7816 the class specifier. */
7817 if (!DECL_EXTERNAL (decl))
7818 var_definition_p = true;
7819 }
7820 /* If the variable has an array type, lay out the type, even if
7821 there is no initializer. It is valid to index through the
7822 array, and we must get TYPE_ALIGN set correctly on the array
7823 type. */
7824 else if (TREE_CODE (type) == ARRAY_TYPE)
7825 layout_type (type);
7826
7827 if (TREE_STATIC (decl)
7828 && !at_function_scope_p ()
7829 && current_function_decl == NULL)
7830 /* So decl is a global variable or a static member of a
7831 non local class. Record the types it uses
7832 so that we can decide later to emit debug info for them. */
7833 record_types_used_by_current_var_decl (decl);
7834 }
7835
7836 /* Add this declaration to the statement-tree. This needs to happen
7837 after the call to check_initializer so that the DECL_EXPR for a
7838 reference temp is added before the DECL_EXPR for the reference itself. */
7839 if (DECL_FUNCTION_SCOPE_P (decl))
7840 {
7841 /* If we're building a variable sized type, and we might be
7842 reachable other than via the top of the current binding
7843 level, then create a new BIND_EXPR so that we deallocate
7844 the object at the right time. */
7845 if (VAR_P (decl)
7846 && DECL_SIZE (decl)
7847 && !TREE_CONSTANT (DECL_SIZE (decl))
7848 && STATEMENT_LIST_HAS_LABEL (cur_stmt_list))
7849 {
7850 tree bind;
7851 bind = build3 (BIND_EXPR, void_type_node, NULL, NULL, NULL);
7852 TREE_SIDE_EFFECTS (bind) = 1;
7853 add_stmt (bind);
7854 BIND_EXPR_BODY (bind) = push_stmt_list ();
7855 }
7856 add_decl_expr (decl);
7857 }
7858
7859 /* Let the middle end know about variables and functions -- but not
7860 static data members in uninstantiated class templates. */
7861 if (VAR_OR_FUNCTION_DECL_P (decl))
7862 {
7863 if (VAR_P (decl))
7864 {
7865 layout_var_decl (decl);
7866 if (!flag_weak)
7867 /* Check again now that we have an initializer. */
7868 maybe_commonize_var (decl);
7869 /* A class-scope constexpr variable with an out-of-class declaration.
7870 C++17 makes them implicitly inline, but still force it out. */
7871 if (DECL_INLINE_VAR_P (decl)
7872 && !DECL_VAR_DECLARED_INLINE_P (decl)
7873 && !DECL_TEMPLATE_INSTANTIATION (decl)
7874 && !in_class_decl)
7875 mark_needed (decl);
7876 }
7877
7878 if (var_definition_p
7879 /* With -fmerge-all-constants, gimplify_init_constructor
7880 might add TREE_STATIC to the variable. */
7881 && (TREE_STATIC (decl) || flag_merge_constants >= 2))
7882 {
7883 /* If a TREE_READONLY variable needs initialization
7884 at runtime, it is no longer readonly and we need to
7885 avoid MEM_READONLY_P being set on RTL created for it. */
7886 if (init)
7887 {
7888 if (TREE_READONLY (decl))
7889 TREE_READONLY (decl) = 0;
7890 was_readonly = 0;
7891 }
7892 else if (was_readonly)
7893 TREE_READONLY (decl) = 1;
7894
7895 /* Likewise if it needs destruction. */
7896 if (!decl_maybe_constant_destruction (decl, type))
7897 TREE_READONLY (decl) = 0;
7898 }
7899
7900 make_rtl_for_nonlocal_decl (decl, init, asmspec);
7901
7902 /* Check for abstractness of the type. Notice that there is no
7903 need to strip array types here since the check for those types
7904 is already done within create_array_type_for_decl. */
7905 abstract_virtuals_error (decl, type);
7906
7907 if (TREE_TYPE (decl) == error_mark_node)
7908 /* No initialization required. */
7909 ;
7910 else if (TREE_CODE (decl) == FUNCTION_DECL)
7911 {
7912 if (init)
7913 {
7914 if (init == ridpointers[(int)RID_DEFAULT])
7915 {
7916 /* An out-of-class default definition is defined at
7917 the point where it is explicitly defaulted. */
7918 if (DECL_DELETED_FN (decl))
7919 maybe_explain_implicit_delete (decl);
7920 else if (DECL_INITIAL (decl) == error_mark_node)
7921 synthesize_method (decl);
7922 }
7923 else
7924 error_at (cp_expr_loc_or_loc (init,
7925 DECL_SOURCE_LOCATION (decl)),
7926 "function %q#D is initialized like a variable",
7927 decl);
7928 }
7929 /* else no initialization required. */
7930 }
7931 else if (DECL_EXTERNAL (decl)
7932 && ! (DECL_LANG_SPECIFIC (decl)
7933 && DECL_NOT_REALLY_EXTERN (decl)))
7934 {
7935 /* check_initializer will have done any constant initialization. */
7936 }
7937 /* A variable definition. */
7938 else if (DECL_FUNCTION_SCOPE_P (decl) && !TREE_STATIC (decl))
7939 /* Initialize the local variable. */
7940 initialize_local_var (decl, init);
7941
7942 /* If a variable is defined, and then a subsequent
7943 definition with external linkage is encountered, we will
7944 get here twice for the same variable. We want to avoid
7945 calling expand_static_init more than once. For variables
7946 that are not static data members, we can call
7947 expand_static_init only when we actually process the
7948 initializer. It is not legal to redeclare a static data
7949 member, so this issue does not arise in that case. */
7950 else if (var_definition_p && TREE_STATIC (decl))
7951 expand_static_init (decl, init);
7952 }
7953
7954 /* If a CLEANUP_STMT was created to destroy a temporary bound to a
7955 reference, insert it in the statement-tree now. */
7956 if (cleanups)
7957 {
7958 unsigned i; tree t;
7959 FOR_EACH_VEC_ELT (*cleanups, i, t)
7960 push_cleanup (decl, t, false);
7961 release_tree_vector (cleanups);
7962 }
7963
7964 if (was_readonly)
7965 TREE_READONLY (decl) = 1;
7966
7967 if (flag_openmp
7968 && VAR_P (decl)
7969 && lookup_attribute ("omp declare target implicit",
7970 DECL_ATTRIBUTES (decl)))
7971 {
7972 DECL_ATTRIBUTES (decl)
7973 = remove_attribute ("omp declare target implicit",
7974 DECL_ATTRIBUTES (decl));
7975 complete_type (TREE_TYPE (decl));
7976 if (!cp_omp_mappable_type (TREE_TYPE (decl)))
7977 {
7978 error ("%q+D in declare target directive does not have mappable"
7979 " type", decl);
7980 cp_omp_emit_unmappable_type_notes (TREE_TYPE (decl));
7981 }
7982 else if (!lookup_attribute ("omp declare target",
7983 DECL_ATTRIBUTES (decl))
7984 && !lookup_attribute ("omp declare target link",
7985 DECL_ATTRIBUTES (decl)))
7986 DECL_ATTRIBUTES (decl)
7987 = tree_cons (get_identifier ("omp declare target"),
7988 NULL_TREE, DECL_ATTRIBUTES (decl));
7989 }
7990
7991 invoke_plugin_callbacks (PLUGIN_FINISH_DECL, decl);
7992 }
7993
7994 /* For class TYPE return itself or some its bases that contain
7995 any direct non-static data members. Return error_mark_node if an
7996 error has been diagnosed. */
7997
7998 static tree
find_decomp_class_base(location_t loc,tree type,tree ret)7999 find_decomp_class_base (location_t loc, tree type, tree ret)
8000 {
8001 bool member_seen = false;
8002 for (tree field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
8003 if (TREE_CODE (field) != FIELD_DECL
8004 || DECL_ARTIFICIAL (field)
8005 || DECL_UNNAMED_BIT_FIELD (field))
8006 continue;
8007 else if (ret)
8008 return type;
8009 else if (ANON_AGGR_TYPE_P (TREE_TYPE (field)))
8010 {
8011 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE)
8012 error_at (loc, "cannot decompose class type %qT because it has an "
8013 "anonymous struct member", type);
8014 else
8015 error_at (loc, "cannot decompose class type %qT because it has an "
8016 "anonymous union member", type);
8017 inform (DECL_SOURCE_LOCATION (field), "declared here");
8018 return error_mark_node;
8019 }
8020 else if (!accessible_p (type, field, true))
8021 {
8022 error_at (loc, "cannot decompose inaccessible member %qD of %qT",
8023 field, type);
8024 inform (DECL_SOURCE_LOCATION (field),
8025 TREE_PRIVATE (field)
8026 ? G_("declared private here")
8027 : G_("declared protected here"));
8028 return error_mark_node;
8029 }
8030 else
8031 member_seen = true;
8032
8033 tree base_binfo, binfo;
8034 tree orig_ret = ret;
8035 int i;
8036 if (member_seen)
8037 ret = type;
8038 for (binfo = TYPE_BINFO (type), i = 0;
8039 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
8040 {
8041 tree t = find_decomp_class_base (loc, TREE_TYPE (base_binfo), ret);
8042 if (t == error_mark_node)
8043 return error_mark_node;
8044 if (t != NULL_TREE && t != ret)
8045 {
8046 if (ret == type)
8047 {
8048 error_at (loc, "cannot decompose class type %qT: both it and "
8049 "its base class %qT have non-static data members",
8050 type, t);
8051 return error_mark_node;
8052 }
8053 else if (orig_ret != NULL_TREE)
8054 return t;
8055 else if (ret != NULL_TREE)
8056 {
8057 error_at (loc, "cannot decompose class type %qT: its base "
8058 "classes %qT and %qT have non-static data "
8059 "members", type, ret, t);
8060 return error_mark_node;
8061 }
8062 else
8063 ret = t;
8064 }
8065 }
8066 return ret;
8067 }
8068
8069 /* Return std::tuple_size<TYPE>::value. */
8070
8071 static tree
get_tuple_size(tree type)8072 get_tuple_size (tree type)
8073 {
8074 tree args = make_tree_vec (1);
8075 TREE_VEC_ELT (args, 0) = type;
8076 tree inst = lookup_template_class (tuple_size_identifier, args,
8077 /*in_decl*/NULL_TREE,
8078 /*context*/std_node,
8079 /*entering_scope*/false, tf_none);
8080 inst = complete_type (inst);
8081 if (inst == error_mark_node || !COMPLETE_TYPE_P (inst))
8082 return NULL_TREE;
8083 tree val = lookup_qualified_name (inst, value_identifier,
8084 /*type*/false, /*complain*/false);
8085 if (TREE_CODE (val) == VAR_DECL || TREE_CODE (val) == CONST_DECL)
8086 val = maybe_constant_value (val);
8087 if (TREE_CODE (val) == INTEGER_CST)
8088 return val;
8089 else
8090 return error_mark_node;
8091 }
8092
8093 /* Return std::tuple_element<I,TYPE>::type. */
8094
8095 static tree
get_tuple_element_type(tree type,unsigned i)8096 get_tuple_element_type (tree type, unsigned i)
8097 {
8098 tree args = make_tree_vec (2);
8099 TREE_VEC_ELT (args, 0) = build_int_cst (integer_type_node, i);
8100 TREE_VEC_ELT (args, 1) = type;
8101 tree inst = lookup_template_class (tuple_element_identifier, args,
8102 /*in_decl*/NULL_TREE,
8103 /*context*/std_node,
8104 /*entering_scope*/false,
8105 tf_warning_or_error);
8106 return make_typename_type (inst, type_identifier,
8107 none_type, tf_warning_or_error);
8108 }
8109
8110 /* Return e.get<i>() or get<i>(e). */
8111
8112 static tree
get_tuple_decomp_init(tree decl,unsigned i)8113 get_tuple_decomp_init (tree decl, unsigned i)
8114 {
8115 tree targs = make_tree_vec (1);
8116 TREE_VEC_ELT (targs, 0) = build_int_cst (integer_type_node, i);
8117
8118 tree etype = TREE_TYPE (decl);
8119 tree e = convert_from_reference (decl);
8120
8121 /* [The id-expression] e is an lvalue if the type of the entity e is an
8122 lvalue reference and an xvalue otherwise. */
8123 if (!TYPE_REF_P (etype)
8124 || TYPE_REF_IS_RVALUE (etype))
8125 e = move (e);
8126
8127 tree fns = lookup_qualified_name (TREE_TYPE (e), get__identifier,
8128 /*type*/false, /*complain*/false);
8129 bool use_member_get = false;
8130
8131 /* To use a member get, member lookup must find at least one
8132 declaration that is a function template
8133 whose first template parameter is a non-type parameter. */
8134 for (lkp_iterator iter (MAYBE_BASELINK_FUNCTIONS (fns)); iter; ++iter)
8135 {
8136 tree fn = *iter;
8137 if (TREE_CODE (fn) == TEMPLATE_DECL)
8138 {
8139 tree tparms = DECL_TEMPLATE_PARMS (fn);
8140 tree parm = TREE_VEC_ELT (INNERMOST_TEMPLATE_PARMS (tparms), 0);
8141 if (TREE_CODE (TREE_VALUE (parm)) == PARM_DECL)
8142 {
8143 use_member_get = true;
8144 break;
8145 }
8146 }
8147 }
8148
8149 if (use_member_get)
8150 {
8151 fns = lookup_template_function (fns, targs);
8152 return build_new_method_call (e, fns, /*args*/NULL,
8153 /*path*/NULL_TREE, LOOKUP_NORMAL,
8154 /*fn_p*/NULL, tf_warning_or_error);
8155 }
8156 else
8157 {
8158 releasing_vec args (make_tree_vector_single (e));
8159 fns = lookup_template_function (get__identifier, targs);
8160 fns = perform_koenig_lookup (fns, args, tf_warning_or_error);
8161 return finish_call_expr (fns, &args, /*novirt*/false,
8162 /*koenig*/true, tf_warning_or_error);
8163 }
8164 }
8165
8166 /* It's impossible to recover the decltype of a tuple decomposition variable
8167 based on the actual type of the variable, so store it in a hash table. */
8168
8169 static GTY((cache)) decl_tree_cache_map *decomp_type_table;
8170
8171 tree
lookup_decomp_type(tree v)8172 lookup_decomp_type (tree v)
8173 {
8174 return *decomp_type_table->get (v);
8175 }
8176
8177 /* Mangle a decomposition declaration if needed. Arguments like
8178 in cp_finish_decomp. */
8179
8180 void
cp_maybe_mangle_decomp(tree decl,tree first,unsigned int count)8181 cp_maybe_mangle_decomp (tree decl, tree first, unsigned int count)
8182 {
8183 if (!processing_template_decl
8184 && !error_operand_p (decl)
8185 && TREE_STATIC (decl))
8186 {
8187 auto_vec<tree, 16> v;
8188 v.safe_grow (count);
8189 tree d = first;
8190 for (unsigned int i = 0; i < count; i++, d = DECL_CHAIN (d))
8191 v[count - i - 1] = d;
8192 SET_DECL_ASSEMBLER_NAME (decl, mangle_decomp (decl, v));
8193 maybe_apply_pragma_weak (decl);
8194 }
8195 }
8196
8197 /* Finish a decomposition declaration. DECL is the underlying declaration
8198 "e", FIRST is the head of a chain of decls for the individual identifiers
8199 chained through DECL_CHAIN in reverse order and COUNT is the number of
8200 those decls. */
8201
8202 void
cp_finish_decomp(tree decl,tree first,unsigned int count)8203 cp_finish_decomp (tree decl, tree first, unsigned int count)
8204 {
8205 if (error_operand_p (decl))
8206 {
8207 error_out:
8208 while (count--)
8209 {
8210 TREE_TYPE (first) = error_mark_node;
8211 if (DECL_HAS_VALUE_EXPR_P (first))
8212 {
8213 SET_DECL_VALUE_EXPR (first, NULL_TREE);
8214 DECL_HAS_VALUE_EXPR_P (first) = 0;
8215 }
8216 first = DECL_CHAIN (first);
8217 }
8218 if (DECL_P (decl) && DECL_NAMESPACE_SCOPE_P (decl))
8219 SET_DECL_ASSEMBLER_NAME (decl, get_identifier ("<decomp>"));
8220 return;
8221 }
8222
8223 location_t loc = DECL_SOURCE_LOCATION (decl);
8224 if (type_dependent_expression_p (decl)
8225 /* This happens for range for when not in templates.
8226 Still add the DECL_VALUE_EXPRs for later processing. */
8227 || (!processing_template_decl
8228 && type_uses_auto (TREE_TYPE (decl))))
8229 {
8230 for (unsigned int i = 0; i < count; i++)
8231 {
8232 if (!DECL_HAS_VALUE_EXPR_P (first))
8233 {
8234 tree v = build_nt (ARRAY_REF, decl,
8235 size_int (count - i - 1),
8236 NULL_TREE, NULL_TREE);
8237 SET_DECL_VALUE_EXPR (first, v);
8238 DECL_HAS_VALUE_EXPR_P (first) = 1;
8239 }
8240 if (processing_template_decl)
8241 fit_decomposition_lang_decl (first, decl);
8242 first = DECL_CHAIN (first);
8243 }
8244 return;
8245 }
8246
8247 auto_vec<tree, 16> v;
8248 v.safe_grow (count);
8249 tree d = first;
8250 for (unsigned int i = 0; i < count; i++, d = DECL_CHAIN (d))
8251 {
8252 v[count - i - 1] = d;
8253 fit_decomposition_lang_decl (d, decl);
8254 }
8255
8256 tree type = TREE_TYPE (decl);
8257 tree dexp = decl;
8258
8259 if (TYPE_REF_P (type))
8260 {
8261 dexp = convert_from_reference (dexp);
8262 type = complete_type (TREE_TYPE (type));
8263 if (type == error_mark_node)
8264 goto error_out;
8265 if (!COMPLETE_TYPE_P (type))
8266 {
8267 error_at (loc, "structured binding refers to incomplete type %qT",
8268 type);
8269 goto error_out;
8270 }
8271 }
8272
8273 tree eltype = NULL_TREE;
8274 unsigned HOST_WIDE_INT eltscnt = 0;
8275 if (TREE_CODE (type) == ARRAY_TYPE)
8276 {
8277 tree nelts;
8278 nelts = array_type_nelts_top (type);
8279 if (nelts == error_mark_node)
8280 goto error_out;
8281 if (!tree_fits_uhwi_p (nelts))
8282 {
8283 error_at (loc, "cannot decompose variable length array %qT", type);
8284 goto error_out;
8285 }
8286 eltscnt = tree_to_uhwi (nelts);
8287 if (count != eltscnt)
8288 {
8289 cnt_mismatch:
8290 if (count > eltscnt)
8291 error_n (loc, count,
8292 "%u name provided for structured binding",
8293 "%u names provided for structured binding", count);
8294 else
8295 error_n (loc, count,
8296 "only %u name provided for structured binding",
8297 "only %u names provided for structured binding", count);
8298 inform_n (loc, eltscnt,
8299 "while %qT decomposes into %wu element",
8300 "while %qT decomposes into %wu elements",
8301 type, eltscnt);
8302 goto error_out;
8303 }
8304 eltype = TREE_TYPE (type);
8305 for (unsigned int i = 0; i < count; i++)
8306 {
8307 TREE_TYPE (v[i]) = eltype;
8308 layout_decl (v[i], 0);
8309 if (processing_template_decl)
8310 continue;
8311 tree t = unshare_expr (dexp);
8312 t = build4_loc (DECL_SOURCE_LOCATION (v[i]), ARRAY_REF,
8313 eltype, t, size_int (i), NULL_TREE,
8314 NULL_TREE);
8315 SET_DECL_VALUE_EXPR (v[i], t);
8316 DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
8317 }
8318 }
8319 /* 2 GNU extensions. */
8320 else if (TREE_CODE (type) == COMPLEX_TYPE)
8321 {
8322 eltscnt = 2;
8323 if (count != eltscnt)
8324 goto cnt_mismatch;
8325 eltype = cp_build_qualified_type (TREE_TYPE (type), TYPE_QUALS (type));
8326 for (unsigned int i = 0; i < count; i++)
8327 {
8328 TREE_TYPE (v[i]) = eltype;
8329 layout_decl (v[i], 0);
8330 if (processing_template_decl)
8331 continue;
8332 tree t = unshare_expr (dexp);
8333 t = build1_loc (DECL_SOURCE_LOCATION (v[i]),
8334 i ? IMAGPART_EXPR : REALPART_EXPR, eltype,
8335 t);
8336 SET_DECL_VALUE_EXPR (v[i], t);
8337 DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
8338 }
8339 }
8340 else if (TREE_CODE (type) == VECTOR_TYPE)
8341 {
8342 if (!TYPE_VECTOR_SUBPARTS (type).is_constant (&eltscnt))
8343 {
8344 error_at (loc, "cannot decompose variable length vector %qT", type);
8345 goto error_out;
8346 }
8347 if (count != eltscnt)
8348 goto cnt_mismatch;
8349 eltype = cp_build_qualified_type (TREE_TYPE (type), TYPE_QUALS (type));
8350 for (unsigned int i = 0; i < count; i++)
8351 {
8352 TREE_TYPE (v[i]) = eltype;
8353 layout_decl (v[i], 0);
8354 if (processing_template_decl)
8355 continue;
8356 tree t = unshare_expr (dexp);
8357 convert_vector_to_array_for_subscript (DECL_SOURCE_LOCATION (v[i]),
8358 &t, size_int (i));
8359 t = build4_loc (DECL_SOURCE_LOCATION (v[i]), ARRAY_REF,
8360 eltype, t, size_int (i), NULL_TREE,
8361 NULL_TREE);
8362 SET_DECL_VALUE_EXPR (v[i], t);
8363 DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
8364 }
8365 }
8366 else if (tree tsize = get_tuple_size (type))
8367 {
8368 if (tsize == error_mark_node)
8369 {
8370 error_at (loc, "%<std::tuple_size<%T>::value%> is not an integral "
8371 "constant expression", type);
8372 goto error_out;
8373 }
8374 if (!tree_fits_uhwi_p (tsize))
8375 {
8376 error_n (loc, count,
8377 "%u name provided for structured binding",
8378 "%u names provided for structured binding", count);
8379 inform (loc, "while %qT decomposes into %E elements",
8380 type, tsize);
8381 goto error_out;
8382 }
8383 eltscnt = tree_to_uhwi (tsize);
8384 if (count != eltscnt)
8385 goto cnt_mismatch;
8386 int save_read = DECL_READ_P (decl);
8387 for (unsigned i = 0; i < count; ++i)
8388 {
8389 location_t sloc = input_location;
8390 location_t dloc = DECL_SOURCE_LOCATION (v[i]);
8391
8392 input_location = dloc;
8393 tree init = get_tuple_decomp_init (decl, i);
8394 tree eltype = (init == error_mark_node ? error_mark_node
8395 : get_tuple_element_type (type, i));
8396 input_location = sloc;
8397
8398 if (VOID_TYPE_P (eltype))
8399 {
8400 error ("%<std::tuple_element<%u, %T>::type%> is %<void%>",
8401 i, type);
8402 eltype = error_mark_node;
8403 }
8404 if (init == error_mark_node || eltype == error_mark_node)
8405 {
8406 inform (dloc, "in initialization of structured binding "
8407 "variable %qD", v[i]);
8408 goto error_out;
8409 }
8410 /* Save the decltype away before reference collapse. */
8411 hash_map_safe_put<hm_ggc> (decomp_type_table, v[i], eltype);
8412 eltype = cp_build_reference_type (eltype, !lvalue_p (init));
8413 TREE_TYPE (v[i]) = eltype;
8414 layout_decl (v[i], 0);
8415 if (DECL_HAS_VALUE_EXPR_P (v[i]))
8416 {
8417 /* In this case the names are variables, not just proxies. */
8418 SET_DECL_VALUE_EXPR (v[i], NULL_TREE);
8419 DECL_HAS_VALUE_EXPR_P (v[i]) = 0;
8420 }
8421 if (!processing_template_decl)
8422 {
8423 copy_linkage (v[i], decl);
8424 cp_finish_decl (v[i], init, /*constexpr*/false,
8425 /*asm*/NULL_TREE, LOOKUP_NORMAL);
8426 }
8427 }
8428 /* Ignore reads from the underlying decl performed during initialization
8429 of the individual variables. If those will be read, we'll mark
8430 the underlying decl as read at that point. */
8431 DECL_READ_P (decl) = save_read;
8432 }
8433 else if (TREE_CODE (type) == UNION_TYPE)
8434 {
8435 error_at (loc, "cannot decompose union type %qT", type);
8436 goto error_out;
8437 }
8438 else if (!CLASS_TYPE_P (type))
8439 {
8440 error_at (loc, "cannot decompose non-array non-class type %qT", type);
8441 goto error_out;
8442 }
8443 else if (LAMBDA_TYPE_P (type))
8444 {
8445 error_at (loc, "cannot decompose lambda closure type %qT", type);
8446 goto error_out;
8447 }
8448 else if (processing_template_decl && complete_type (type) == error_mark_node)
8449 goto error_out;
8450 else if (processing_template_decl && !COMPLETE_TYPE_P (type))
8451 pedwarn (loc, 0, "structured binding refers to incomplete class type %qT",
8452 type);
8453 else
8454 {
8455 tree btype = find_decomp_class_base (loc, type, NULL_TREE);
8456 if (btype == error_mark_node)
8457 goto error_out;
8458 else if (btype == NULL_TREE)
8459 {
8460 error_at (loc, "cannot decompose class type %qT without non-static "
8461 "data members", type);
8462 goto error_out;
8463 }
8464 for (tree field = TYPE_FIELDS (btype); field; field = TREE_CHAIN (field))
8465 if (TREE_CODE (field) != FIELD_DECL
8466 || DECL_ARTIFICIAL (field)
8467 || DECL_UNNAMED_BIT_FIELD (field))
8468 continue;
8469 else
8470 eltscnt++;
8471 if (count != eltscnt)
8472 goto cnt_mismatch;
8473 tree t = dexp;
8474 if (type != btype)
8475 {
8476 t = convert_to_base (t, btype, /*check_access*/true,
8477 /*nonnull*/false, tf_warning_or_error);
8478 type = btype;
8479 }
8480 unsigned int i = 0;
8481 for (tree field = TYPE_FIELDS (btype); field; field = TREE_CHAIN (field))
8482 if (TREE_CODE (field) != FIELD_DECL
8483 || DECL_ARTIFICIAL (field)
8484 || DECL_UNNAMED_BIT_FIELD (field))
8485 continue;
8486 else
8487 {
8488 tree tt = finish_non_static_data_member (field, unshare_expr (t),
8489 NULL_TREE);
8490 if (REFERENCE_REF_P (tt))
8491 tt = TREE_OPERAND (tt, 0);
8492 TREE_TYPE (v[i]) = TREE_TYPE (tt);
8493 layout_decl (v[i], 0);
8494 if (!processing_template_decl)
8495 {
8496 SET_DECL_VALUE_EXPR (v[i], tt);
8497 DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
8498 }
8499 i++;
8500 }
8501 }
8502 if (processing_template_decl)
8503 {
8504 for (unsigned int i = 0; i < count; i++)
8505 if (!DECL_HAS_VALUE_EXPR_P (v[i]))
8506 {
8507 tree a = build_nt (ARRAY_REF, decl, size_int (i),
8508 NULL_TREE, NULL_TREE);
8509 SET_DECL_VALUE_EXPR (v[i], a);
8510 DECL_HAS_VALUE_EXPR_P (v[i]) = 1;
8511 }
8512 }
8513 }
8514
8515 /* Returns a declaration for a VAR_DECL as if:
8516
8517 extern "C" TYPE NAME;
8518
8519 had been seen. Used to create compiler-generated global
8520 variables. */
8521
8522 static tree
declare_global_var(tree name,tree type)8523 declare_global_var (tree name, tree type)
8524 {
8525 tree decl;
8526
8527 push_to_top_level ();
8528 decl = build_decl (input_location, VAR_DECL, name, type);
8529 TREE_PUBLIC (decl) = 1;
8530 DECL_EXTERNAL (decl) = 1;
8531 DECL_ARTIFICIAL (decl) = 1;
8532 DECL_CONTEXT (decl) = FROB_CONTEXT (global_namespace);
8533 /* If the user has explicitly declared this variable (perhaps
8534 because the code we are compiling is part of a low-level runtime
8535 library), then it is possible that our declaration will be merged
8536 with theirs by pushdecl. */
8537 decl = pushdecl (decl);
8538 cp_finish_decl (decl, NULL_TREE, false, NULL_TREE, 0);
8539 pop_from_top_level ();
8540
8541 return decl;
8542 }
8543
8544 /* Returns the type for the argument to "__cxa_atexit" (or "atexit",
8545 if "__cxa_atexit" is not being used) corresponding to the function
8546 to be called when the program exits. */
8547
8548 static tree
get_atexit_fn_ptr_type(void)8549 get_atexit_fn_ptr_type (void)
8550 {
8551 tree fn_type;
8552
8553 if (!atexit_fn_ptr_type_node)
8554 {
8555 tree arg_type;
8556 if (flag_use_cxa_atexit
8557 && !targetm.cxx.use_atexit_for_cxa_atexit ())
8558 /* The parameter to "__cxa_atexit" is "void (*)(void *)". */
8559 arg_type = ptr_type_node;
8560 else
8561 /* The parameter to "atexit" is "void (*)(void)". */
8562 arg_type = NULL_TREE;
8563
8564 fn_type = build_function_type_list (void_type_node,
8565 arg_type, NULL_TREE);
8566 atexit_fn_ptr_type_node = build_pointer_type (fn_type);
8567 }
8568
8569 return atexit_fn_ptr_type_node;
8570 }
8571
8572 /* Returns a pointer to the `atexit' function. Note that if
8573 FLAG_USE_CXA_ATEXIT is nonzero, then this will actually be the new
8574 `__cxa_atexit' function specified in the IA64 C++ ABI. */
8575
8576 static tree
get_atexit_node(void)8577 get_atexit_node (void)
8578 {
8579 tree atexit_fndecl;
8580 tree fn_type;
8581 tree fn_ptr_type;
8582 const char *name;
8583 bool use_aeabi_atexit;
8584
8585 if (atexit_node)
8586 return atexit_node;
8587
8588 if (flag_use_cxa_atexit && !targetm.cxx.use_atexit_for_cxa_atexit ())
8589 {
8590 /* The declaration for `__cxa_atexit' is:
8591
8592 int __cxa_atexit (void (*)(void *), void *, void *)
8593
8594 We build up the argument types and then the function type
8595 itself. */
8596 tree argtype0, argtype1, argtype2;
8597
8598 use_aeabi_atexit = targetm.cxx.use_aeabi_atexit ();
8599 /* First, build the pointer-to-function type for the first
8600 argument. */
8601 fn_ptr_type = get_atexit_fn_ptr_type ();
8602 /* Then, build the rest of the argument types. */
8603 argtype2 = ptr_type_node;
8604 if (use_aeabi_atexit)
8605 {
8606 argtype1 = fn_ptr_type;
8607 argtype0 = ptr_type_node;
8608 }
8609 else
8610 {
8611 argtype1 = ptr_type_node;
8612 argtype0 = fn_ptr_type;
8613 }
8614 /* And the final __cxa_atexit type. */
8615 fn_type = build_function_type_list (integer_type_node,
8616 argtype0, argtype1, argtype2,
8617 NULL_TREE);
8618 if (use_aeabi_atexit)
8619 name = "__aeabi_atexit";
8620 else
8621 name = "__cxa_atexit";
8622 }
8623 else
8624 {
8625 /* The declaration for `atexit' is:
8626
8627 int atexit (void (*)());
8628
8629 We build up the argument types and then the function type
8630 itself. */
8631 fn_ptr_type = get_atexit_fn_ptr_type ();
8632 /* Build the final atexit type. */
8633 fn_type = build_function_type_list (integer_type_node,
8634 fn_ptr_type, NULL_TREE);
8635 name = "atexit";
8636 }
8637
8638 /* Now, build the function declaration. */
8639 push_lang_context (lang_name_c);
8640 atexit_fndecl = build_library_fn_ptr (name, fn_type, ECF_LEAF | ECF_NOTHROW);
8641 mark_used (atexit_fndecl);
8642 pop_lang_context ();
8643 atexit_node = decay_conversion (atexit_fndecl, tf_warning_or_error);
8644
8645 return atexit_node;
8646 }
8647
8648 /* Like get_atexit_node, but for thread-local cleanups. */
8649
8650 static tree
get_thread_atexit_node(void)8651 get_thread_atexit_node (void)
8652 {
8653 /* The declaration for `__cxa_thread_atexit' is:
8654
8655 int __cxa_thread_atexit (void (*)(void *), void *, void *) */
8656 tree fn_type = build_function_type_list (integer_type_node,
8657 get_atexit_fn_ptr_type (),
8658 ptr_type_node, ptr_type_node,
8659 NULL_TREE);
8660
8661 /* Now, build the function declaration. */
8662 tree atexit_fndecl = build_library_fn_ptr ("__cxa_thread_atexit", fn_type,
8663 ECF_LEAF | ECF_NOTHROW);
8664 return decay_conversion (atexit_fndecl, tf_warning_or_error);
8665 }
8666
8667 /* Returns the __dso_handle VAR_DECL. */
8668
8669 static tree
get_dso_handle_node(void)8670 get_dso_handle_node (void)
8671 {
8672 if (dso_handle_node)
8673 return dso_handle_node;
8674
8675 /* Declare the variable. */
8676 dso_handle_node = declare_global_var (get_identifier ("__dso_handle"),
8677 ptr_type_node);
8678
8679 #ifdef HAVE_GAS_HIDDEN
8680 if (dso_handle_node != error_mark_node)
8681 {
8682 DECL_VISIBILITY (dso_handle_node) = VISIBILITY_HIDDEN;
8683 DECL_VISIBILITY_SPECIFIED (dso_handle_node) = 1;
8684 }
8685 #endif
8686
8687 return dso_handle_node;
8688 }
8689
8690 /* Begin a new function with internal linkage whose job will be simply
8691 to destroy some particular variable. */
8692
8693 static GTY(()) int start_cleanup_cnt;
8694
8695 static tree
start_cleanup_fn(void)8696 start_cleanup_fn (void)
8697 {
8698 char name[32];
8699 tree fntype;
8700 tree fndecl;
8701 bool use_cxa_atexit = flag_use_cxa_atexit
8702 && !targetm.cxx.use_atexit_for_cxa_atexit ();
8703
8704 push_to_top_level ();
8705
8706 /* No need to mangle this. */
8707 push_lang_context (lang_name_c);
8708
8709 /* Build the name of the function. */
8710 sprintf (name, "__tcf_%d", start_cleanup_cnt++);
8711 /* Build the function declaration. */
8712 fntype = TREE_TYPE (get_atexit_fn_ptr_type ());
8713 fndecl = build_lang_decl (FUNCTION_DECL, get_identifier (name), fntype);
8714 /* It's a function with internal linkage, generated by the
8715 compiler. */
8716 TREE_PUBLIC (fndecl) = 0;
8717 DECL_ARTIFICIAL (fndecl) = 1;
8718 /* Make the function `inline' so that it is only emitted if it is
8719 actually needed. It is unlikely that it will be inlined, since
8720 it is only called via a function pointer, but we avoid unnecessary
8721 emissions this way. */
8722 DECL_DECLARED_INLINE_P (fndecl) = 1;
8723 DECL_INTERFACE_KNOWN (fndecl) = 1;
8724 /* Build the parameter. */
8725 if (use_cxa_atexit)
8726 {
8727 tree parmdecl = cp_build_parm_decl (fndecl, NULL_TREE, ptr_type_node);
8728 TREE_USED (parmdecl) = 1;
8729 DECL_READ_P (parmdecl) = 1;
8730 DECL_ARGUMENTS (fndecl) = parmdecl;
8731 }
8732
8733 pushdecl (fndecl);
8734 start_preparsed_function (fndecl, NULL_TREE, SF_PRE_PARSED);
8735
8736 pop_lang_context ();
8737
8738 return current_function_decl;
8739 }
8740
8741 /* Finish the cleanup function begun by start_cleanup_fn. */
8742
8743 static void
end_cleanup_fn(void)8744 end_cleanup_fn (void)
8745 {
8746 expand_or_defer_fn (finish_function (/*inline_p=*/false));
8747
8748 pop_from_top_level ();
8749 }
8750
8751 /* Generate code to handle the destruction of DECL, an object with
8752 static storage duration. */
8753
8754 tree
register_dtor_fn(tree decl)8755 register_dtor_fn (tree decl)
8756 {
8757 tree cleanup;
8758 tree addr;
8759 tree compound_stmt;
8760 tree fcall;
8761 tree type;
8762 bool ob_parm, dso_parm, use_dtor;
8763 tree arg0, arg1, arg2;
8764 tree atex_node;
8765
8766 type = TREE_TYPE (decl);
8767 if (TYPE_HAS_TRIVIAL_DESTRUCTOR (type))
8768 return void_node;
8769
8770 if (decl_maybe_constant_destruction (decl, type)
8771 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
8772 {
8773 cxx_maybe_build_cleanup (decl, tf_warning_or_error);
8774 return void_node;
8775 }
8776
8777 /* If we're using "__cxa_atexit" (or "__cxa_thread_atexit" or
8778 "__aeabi_atexit"), and DECL is a class object, we can just pass the
8779 destructor to "__cxa_atexit"; we don't have to build a temporary
8780 function to do the cleanup. */
8781 dso_parm = (flag_use_cxa_atexit
8782 && !targetm.cxx.use_atexit_for_cxa_atexit ());
8783 ob_parm = (CP_DECL_THREAD_LOCAL_P (decl) || dso_parm);
8784 use_dtor = ob_parm && CLASS_TYPE_P (type);
8785 if (use_dtor)
8786 {
8787 cleanup = get_class_binding (type, complete_dtor_identifier);
8788
8789 /* Make sure it is accessible. */
8790 perform_or_defer_access_check (TYPE_BINFO (type), cleanup, cleanup,
8791 tf_warning_or_error);
8792 }
8793 else
8794 {
8795 /* Call build_cleanup before we enter the anonymous function so
8796 that any access checks will be done relative to the current
8797 scope, rather than the scope of the anonymous function. */
8798 build_cleanup (decl);
8799
8800 /* Now start the function. */
8801 cleanup = start_cleanup_fn ();
8802
8803 /* Now, recompute the cleanup. It may contain SAVE_EXPRs that refer
8804 to the original function, rather than the anonymous one. That
8805 will make the back end think that nested functions are in use,
8806 which causes confusion. */
8807 push_deferring_access_checks (dk_no_check);
8808 fcall = build_cleanup (decl);
8809 pop_deferring_access_checks ();
8810
8811 /* Create the body of the anonymous function. */
8812 compound_stmt = begin_compound_stmt (BCS_FN_BODY);
8813 finish_expr_stmt (fcall);
8814 finish_compound_stmt (compound_stmt);
8815 end_cleanup_fn ();
8816 }
8817
8818 /* Call atexit with the cleanup function. */
8819 mark_used (cleanup);
8820 cleanup = build_address (cleanup);
8821
8822 if (CP_DECL_THREAD_LOCAL_P (decl))
8823 atex_node = get_thread_atexit_node ();
8824 else
8825 atex_node = get_atexit_node ();
8826
8827 if (use_dtor)
8828 {
8829 /* We must convert CLEANUP to the type that "__cxa_atexit"
8830 expects. */
8831 cleanup = build_nop (get_atexit_fn_ptr_type (), cleanup);
8832 /* "__cxa_atexit" will pass the address of DECL to the
8833 cleanup function. */
8834 mark_used (decl);
8835 addr = build_address (decl);
8836 /* The declared type of the parameter to "__cxa_atexit" is
8837 "void *". For plain "T*", we could just let the
8838 machinery in cp_build_function_call convert it -- but if the
8839 type is "cv-qualified T *", then we need to convert it
8840 before passing it in, to avoid spurious errors. */
8841 addr = build_nop (ptr_type_node, addr);
8842 }
8843 else
8844 /* Since the cleanup functions we build ignore the address
8845 they're given, there's no reason to pass the actual address
8846 in, and, in general, it's cheaper to pass NULL than any
8847 other value. */
8848 addr = null_pointer_node;
8849
8850 if (dso_parm)
8851 arg2 = cp_build_addr_expr (get_dso_handle_node (),
8852 tf_warning_or_error);
8853 else if (ob_parm)
8854 /* Just pass NULL to the dso handle parm if we don't actually
8855 have a DSO handle on this target. */
8856 arg2 = null_pointer_node;
8857 else
8858 arg2 = NULL_TREE;
8859
8860 if (ob_parm)
8861 {
8862 if (!CP_DECL_THREAD_LOCAL_P (decl)
8863 && targetm.cxx.use_aeabi_atexit ())
8864 {
8865 arg1 = cleanup;
8866 arg0 = addr;
8867 }
8868 else
8869 {
8870 arg1 = addr;
8871 arg0 = cleanup;
8872 }
8873 }
8874 else
8875 {
8876 arg0 = cleanup;
8877 arg1 = NULL_TREE;
8878 }
8879 return cp_build_function_call_nary (atex_node, tf_warning_or_error,
8880 arg0, arg1, arg2, NULL_TREE);
8881 }
8882
8883 /* DECL is a VAR_DECL with static storage duration. INIT, if present,
8884 is its initializer. Generate code to handle the construction
8885 and destruction of DECL. */
8886
8887 static void
expand_static_init(tree decl,tree init)8888 expand_static_init (tree decl, tree init)
8889 {
8890 gcc_assert (VAR_P (decl));
8891 gcc_assert (TREE_STATIC (decl));
8892
8893 /* Some variables require no dynamic initialization. */
8894 if (decl_maybe_constant_destruction (decl, TREE_TYPE (decl)))
8895 {
8896 /* Make sure the destructor is callable. */
8897 cxx_maybe_build_cleanup (decl, tf_warning_or_error);
8898 if (!init)
8899 return;
8900 }
8901
8902 if (CP_DECL_THREAD_LOCAL_P (decl) && DECL_GNU_TLS_P (decl)
8903 && !DECL_FUNCTION_SCOPE_P (decl))
8904 {
8905 location_t dloc = DECL_SOURCE_LOCATION (decl);
8906 if (init)
8907 error_at (dloc, "non-local variable %qD declared %<__thread%> "
8908 "needs dynamic initialization", decl);
8909 else
8910 error_at (dloc, "non-local variable %qD declared %<__thread%> "
8911 "has a non-trivial destructor", decl);
8912 static bool informed;
8913 if (!informed)
8914 {
8915 inform (dloc, "C++11 %<thread_local%> allows dynamic "
8916 "initialization and destruction");
8917 informed = true;
8918 }
8919 return;
8920 }
8921
8922 if (DECL_FUNCTION_SCOPE_P (decl))
8923 {
8924 /* Emit code to perform this initialization but once. */
8925 tree if_stmt = NULL_TREE, inner_if_stmt = NULL_TREE;
8926 tree then_clause = NULL_TREE, inner_then_clause = NULL_TREE;
8927 tree guard, guard_addr;
8928 tree flag, begin;
8929 /* We don't need thread-safety code for thread-local vars. */
8930 bool thread_guard = (flag_threadsafe_statics
8931 && !CP_DECL_THREAD_LOCAL_P (decl));
8932
8933 /* Emit code to perform this initialization but once. This code
8934 looks like:
8935
8936 static <type> guard;
8937 if (!__atomic_load (guard.first_byte)) {
8938 if (__cxa_guard_acquire (&guard)) {
8939 bool flag = false;
8940 try {
8941 // Do initialization.
8942 flag = true; __cxa_guard_release (&guard);
8943 // Register variable for destruction at end of program.
8944 } catch {
8945 if (!flag) __cxa_guard_abort (&guard);
8946 }
8947 }
8948 }
8949
8950 Note that the `flag' variable is only set to 1 *after* the
8951 initialization is complete. This ensures that an exception,
8952 thrown during the construction, will cause the variable to
8953 reinitialized when we pass through this code again, as per:
8954
8955 [stmt.dcl]
8956
8957 If the initialization exits by throwing an exception, the
8958 initialization is not complete, so it will be tried again
8959 the next time control enters the declaration.
8960
8961 This process should be thread-safe, too; multiple threads
8962 should not be able to initialize the variable more than
8963 once. */
8964
8965 /* Create the guard variable. */
8966 guard = get_guard (decl);
8967
8968 /* Begin the conditional initialization. */
8969 if_stmt = begin_if_stmt ();
8970
8971 finish_if_stmt_cond (get_guard_cond (guard, thread_guard), if_stmt);
8972 then_clause = begin_compound_stmt (BCS_NO_SCOPE);
8973
8974 if (thread_guard)
8975 {
8976 tree vfntype = NULL_TREE;
8977 tree acquire_name, release_name, abort_name;
8978 tree acquire_fn, release_fn, abort_fn;
8979 guard_addr = build_address (guard);
8980
8981 acquire_name = get_identifier ("__cxa_guard_acquire");
8982 release_name = get_identifier ("__cxa_guard_release");
8983 abort_name = get_identifier ("__cxa_guard_abort");
8984 acquire_fn = get_global_binding (acquire_name);
8985 release_fn = get_global_binding (release_name);
8986 abort_fn = get_global_binding (abort_name);
8987 if (!acquire_fn)
8988 acquire_fn = push_library_fn
8989 (acquire_name, build_function_type_list (integer_type_node,
8990 TREE_TYPE (guard_addr),
8991 NULL_TREE),
8992 NULL_TREE, ECF_NOTHROW);
8993 if (!release_fn || !abort_fn)
8994 vfntype = build_function_type_list (void_type_node,
8995 TREE_TYPE (guard_addr),
8996 NULL_TREE);
8997 if (!release_fn)
8998 release_fn = push_library_fn (release_name, vfntype, NULL_TREE,
8999 ECF_NOTHROW);
9000 if (!abort_fn)
9001 abort_fn = push_library_fn (abort_name, vfntype, NULL_TREE,
9002 ECF_NOTHROW | ECF_LEAF);
9003
9004 inner_if_stmt = begin_if_stmt ();
9005 finish_if_stmt_cond (build_call_n (acquire_fn, 1, guard_addr),
9006 inner_if_stmt);
9007
9008 inner_then_clause = begin_compound_stmt (BCS_NO_SCOPE);
9009 begin = get_target_expr (boolean_false_node);
9010 flag = TARGET_EXPR_SLOT (begin);
9011
9012 TARGET_EXPR_CLEANUP (begin)
9013 = build3 (COND_EXPR, void_type_node, flag,
9014 void_node,
9015 build_call_n (abort_fn, 1, guard_addr));
9016 CLEANUP_EH_ONLY (begin) = 1;
9017
9018 /* Do the initialization itself. */
9019 init = add_stmt_to_compound (begin, init);
9020 init = add_stmt_to_compound (init,
9021 build2 (MODIFY_EXPR, void_type_node,
9022 flag, boolean_true_node));
9023
9024 /* Use atexit to register a function for destroying this static
9025 variable. Do this before calling __cxa_guard_release. */
9026 init = add_stmt_to_compound (init, register_dtor_fn (decl));
9027
9028 init = add_stmt_to_compound (init, build_call_n (release_fn, 1,
9029 guard_addr));
9030 }
9031 else
9032 {
9033 init = add_stmt_to_compound (init, set_guard (guard));
9034
9035 /* Use atexit to register a function for destroying this static
9036 variable. */
9037 init = add_stmt_to_compound (init, register_dtor_fn (decl));
9038 }
9039
9040 finish_expr_stmt (init);
9041
9042 if (thread_guard)
9043 {
9044 finish_compound_stmt (inner_then_clause);
9045 finish_then_clause (inner_if_stmt);
9046 finish_if_stmt (inner_if_stmt);
9047 }
9048
9049 finish_compound_stmt (then_clause);
9050 finish_then_clause (if_stmt);
9051 finish_if_stmt (if_stmt);
9052 }
9053 else if (CP_DECL_THREAD_LOCAL_P (decl))
9054 tls_aggregates = tree_cons (init, decl, tls_aggregates);
9055 else
9056 static_aggregates = tree_cons (init, decl, static_aggregates);
9057 }
9058
9059
9060 /* Make TYPE a complete type based on INITIAL_VALUE.
9061 Return 0 if successful, 1 if INITIAL_VALUE can't be deciphered,
9062 2 if there was no information (in which case assume 0 if DO_DEFAULT),
9063 3 if the initializer list is empty (in pedantic mode). */
9064
9065 int
cp_complete_array_type(tree * ptype,tree initial_value,bool do_default)9066 cp_complete_array_type (tree *ptype, tree initial_value, bool do_default)
9067 {
9068 int failure;
9069 tree type, elt_type;
9070
9071 /* Don't get confused by a CONSTRUCTOR for some other type. */
9072 if (initial_value && TREE_CODE (initial_value) == CONSTRUCTOR
9073 && !BRACE_ENCLOSED_INITIALIZER_P (initial_value)
9074 && TREE_CODE (TREE_TYPE (initial_value)) != ARRAY_TYPE)
9075 return 1;
9076
9077 if (initial_value)
9078 {
9079 unsigned HOST_WIDE_INT i;
9080 tree value;
9081
9082 /* An array of character type can be initialized from a
9083 brace-enclosed string constant.
9084
9085 FIXME: this code is duplicated from reshape_init. Probably
9086 we should just call reshape_init here? */
9087 if (char_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (*ptype)))
9088 && TREE_CODE (initial_value) == CONSTRUCTOR
9089 && !vec_safe_is_empty (CONSTRUCTOR_ELTS (initial_value)))
9090 {
9091 vec<constructor_elt, va_gc> *v = CONSTRUCTOR_ELTS (initial_value);
9092 tree value = (*v)[0].value;
9093 STRIP_ANY_LOCATION_WRAPPER (value);
9094
9095 if (TREE_CODE (value) == STRING_CST
9096 && v->length () == 1)
9097 initial_value = value;
9098 }
9099
9100 /* If any of the elements are parameter packs, we can't actually
9101 complete this type now because the array size is dependent. */
9102 if (TREE_CODE (initial_value) == CONSTRUCTOR)
9103 {
9104 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (initial_value),
9105 i, value)
9106 {
9107 if (PACK_EXPANSION_P (value))
9108 return 0;
9109 }
9110 }
9111 }
9112
9113 failure = complete_array_type (ptype, initial_value, do_default);
9114
9115 /* We can create the array before the element type is complete, which
9116 means that we didn't have these two bits set in the original type
9117 either. In completing the type, we are expected to propagate these
9118 bits. See also complete_type which does the same thing for arrays
9119 of fixed size. */
9120 type = *ptype;
9121 if (type != error_mark_node && TYPE_DOMAIN (type))
9122 {
9123 elt_type = TREE_TYPE (type);
9124 TYPE_NEEDS_CONSTRUCTING (type) = TYPE_NEEDS_CONSTRUCTING (elt_type);
9125 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
9126 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (elt_type);
9127 }
9128
9129 return failure;
9130 }
9131
9132 /* As above, but either give an error or reject zero-size arrays, depending
9133 on COMPLAIN. */
9134
9135 int
cp_complete_array_type_or_error(tree * ptype,tree initial_value,bool do_default,tsubst_flags_t complain)9136 cp_complete_array_type_or_error (tree *ptype, tree initial_value,
9137 bool do_default, tsubst_flags_t complain)
9138 {
9139 int failure;
9140 bool sfinae = !(complain & tf_error);
9141 /* In SFINAE context we can't be lenient about zero-size arrays. */
9142 if (sfinae)
9143 ++pedantic;
9144 failure = cp_complete_array_type (ptype, initial_value, do_default);
9145 if (sfinae)
9146 --pedantic;
9147 if (failure)
9148 {
9149 if (sfinae)
9150 /* Not an error. */;
9151 else if (failure == 1)
9152 error ("initializer fails to determine size of %qT", *ptype);
9153 else if (failure == 2)
9154 {
9155 if (do_default)
9156 error ("array size missing in %qT", *ptype);
9157 }
9158 else if (failure == 3)
9159 error ("zero-size array %qT", *ptype);
9160 *ptype = error_mark_node;
9161 }
9162 return failure;
9163 }
9164
9165 /* Return zero if something is declared to be a member of type
9166 CTYPE when in the context of CUR_TYPE. STRING is the error
9167 message to print in that case. Otherwise, quietly return 1. */
9168
9169 static int
member_function_or_else(tree ctype,tree cur_type,enum overload_flags flags)9170 member_function_or_else (tree ctype, tree cur_type, enum overload_flags flags)
9171 {
9172 if (ctype && ctype != cur_type)
9173 {
9174 if (flags == DTOR_FLAG)
9175 error ("destructor for alien class %qT cannot be a member", ctype);
9176 else
9177 error ("constructor for alien class %qT cannot be a member", ctype);
9178 return 0;
9179 }
9180 return 1;
9181 }
9182
9183 /* Subroutine of `grokdeclarator'. */
9184
9185 /* Generate errors possibly applicable for a given set of specifiers.
9186 This is for ARM $7.1.2. */
9187
9188 static void
bad_specifiers(tree object,enum bad_spec_place type,int virtualp,int quals,int inlinep,int friendp,int raises,const location_t * locations)9189 bad_specifiers (tree object,
9190 enum bad_spec_place type,
9191 int virtualp,
9192 int quals,
9193 int inlinep,
9194 int friendp,
9195 int raises,
9196 const location_t* locations)
9197 {
9198 switch (type)
9199 {
9200 case BSP_VAR:
9201 if (virtualp)
9202 error_at (locations[ds_virtual],
9203 "%qD declared as a %<virtual%> variable", object);
9204 if (quals)
9205 error ("%<const%> and %<volatile%> function specifiers on "
9206 "%qD invalid in variable declaration", object);
9207 break;
9208 case BSP_PARM:
9209 if (virtualp)
9210 error_at (locations[ds_virtual],
9211 "%qD declared as a %<virtual%> parameter", object);
9212 if (inlinep)
9213 error_at (locations[ds_inline],
9214 "%qD declared as an %<inline%> parameter", object);
9215 if (quals)
9216 error ("%<const%> and %<volatile%> function specifiers on "
9217 "%qD invalid in parameter declaration", object);
9218 break;
9219 case BSP_TYPE:
9220 if (virtualp)
9221 error_at (locations[ds_virtual],
9222 "%qD declared as a %<virtual%> type", object);
9223 if (inlinep)
9224 error_at (locations[ds_inline],
9225 "%qD declared as an %<inline%> type", object);
9226 if (quals)
9227 error ("%<const%> and %<volatile%> function specifiers on "
9228 "%qD invalid in type declaration", object);
9229 break;
9230 case BSP_FIELD:
9231 if (virtualp)
9232 error_at (locations[ds_virtual],
9233 "%qD declared as a %<virtual%> field", object);
9234 if (inlinep)
9235 error_at (locations[ds_inline],
9236 "%qD declared as an %<inline%> field", object);
9237 if (quals)
9238 error ("%<const%> and %<volatile%> function specifiers on "
9239 "%qD invalid in field declaration", object);
9240 break;
9241 default:
9242 gcc_unreachable();
9243 }
9244 if (friendp)
9245 error ("%q+D declared as a friend", object);
9246 if (raises
9247 && !flag_noexcept_type
9248 && (TREE_CODE (object) == TYPE_DECL
9249 || (!TYPE_PTRFN_P (TREE_TYPE (object))
9250 && !TYPE_REFFN_P (TREE_TYPE (object))
9251 && !TYPE_PTRMEMFUNC_P (TREE_TYPE (object)))))
9252 error ("%q+D declared with an exception specification", object);
9253 }
9254
9255 /* DECL is a member function or static data member and is presently
9256 being defined. Check that the definition is taking place in a
9257 valid namespace. */
9258
9259 static void
check_class_member_definition_namespace(tree decl)9260 check_class_member_definition_namespace (tree decl)
9261 {
9262 /* These checks only apply to member functions and static data
9263 members. */
9264 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
9265 /* We check for problems with specializations in pt.c in
9266 check_specialization_namespace, where we can issue better
9267 diagnostics. */
9268 if (processing_specialization)
9269 return;
9270 /* We check this in check_explicit_instantiation_namespace. */
9271 if (processing_explicit_instantiation)
9272 return;
9273 /* [class.mfct]
9274
9275 A member function definition that appears outside of the
9276 class definition shall appear in a namespace scope enclosing
9277 the class definition.
9278
9279 [class.static.data]
9280
9281 The definition for a static data member shall appear in a
9282 namespace scope enclosing the member's class definition. */
9283 if (!is_ancestor (current_namespace, DECL_CONTEXT (decl)))
9284 permerror (input_location, "definition of %qD is not in namespace enclosing %qT",
9285 decl, DECL_CONTEXT (decl));
9286 }
9287
9288 /* Build a PARM_DECL for the "this" parameter of FN. TYPE is the
9289 METHOD_TYPE for a non-static member function; QUALS are the
9290 cv-qualifiers that apply to the function. */
9291
9292 tree
build_this_parm(tree fn,tree type,cp_cv_quals quals)9293 build_this_parm (tree fn, tree type, cp_cv_quals quals)
9294 {
9295 tree this_type;
9296 tree qual_type;
9297 tree parm;
9298 cp_cv_quals this_quals;
9299
9300 if (CLASS_TYPE_P (type))
9301 {
9302 this_type
9303 = cp_build_qualified_type (type, quals & ~TYPE_QUAL_RESTRICT);
9304 this_type = build_pointer_type (this_type);
9305 }
9306 else
9307 this_type = type_of_this_parm (type);
9308 /* The `this' parameter is implicitly `const'; it cannot be
9309 assigned to. */
9310 this_quals = (quals & TYPE_QUAL_RESTRICT) | TYPE_QUAL_CONST;
9311 qual_type = cp_build_qualified_type (this_type, this_quals);
9312 parm = build_artificial_parm (fn, this_identifier, qual_type);
9313 cp_apply_type_quals_to_decl (this_quals, parm);
9314 return parm;
9315 }
9316
9317 /* DECL is a static member function. Complain if it was declared
9318 with function-cv-quals. */
9319
9320 static void
check_static_quals(tree decl,cp_cv_quals quals)9321 check_static_quals (tree decl, cp_cv_quals quals)
9322 {
9323 if (quals != TYPE_UNQUALIFIED)
9324 error ("static member function %q#D declared with type qualifiers",
9325 decl);
9326 }
9327
9328 // Check that FN takes no arguments and returns bool.
9329 static void
check_concept_fn(tree fn)9330 check_concept_fn (tree fn)
9331 {
9332 // A constraint is nullary.
9333 if (DECL_ARGUMENTS (fn))
9334 error_at (DECL_SOURCE_LOCATION (fn),
9335 "concept %q#D declared with function parameters", fn);
9336
9337 // The declared return type of the concept shall be bool, and
9338 // it shall not be deduced from it definition.
9339 tree type = TREE_TYPE (TREE_TYPE (fn));
9340 if (is_auto (type))
9341 error_at (DECL_SOURCE_LOCATION (fn),
9342 "concept %q#D declared with a deduced return type", fn);
9343 else if (type != boolean_type_node)
9344 error_at (DECL_SOURCE_LOCATION (fn),
9345 "concept %q#D with non-%<bool%> return type %qT", fn, type);
9346 }
9347
9348 /* Helper function. Replace the temporary this parameter injected
9349 during cp_finish_omp_declare_simd with the real this parameter. */
9350
9351 static tree
declare_simd_adjust_this(tree * tp,int * walk_subtrees,void * data)9352 declare_simd_adjust_this (tree *tp, int *walk_subtrees, void *data)
9353 {
9354 tree this_parm = (tree) data;
9355 if (TREE_CODE (*tp) == PARM_DECL
9356 && DECL_NAME (*tp) == this_identifier
9357 && *tp != this_parm)
9358 *tp = this_parm;
9359 else if (TYPE_P (*tp))
9360 *walk_subtrees = 0;
9361 return NULL_TREE;
9362 }
9363
9364 /* CTYPE is class type, or null if non-class.
9365 TYPE is type this FUNCTION_DECL should have, either FUNCTION_TYPE
9366 or METHOD_TYPE.
9367 DECLARATOR is the function's name.
9368 PARMS is a chain of PARM_DECLs for the function.
9369 VIRTUALP is truthvalue of whether the function is virtual or not.
9370 FLAGS are to be passed through to `grokclassfn'.
9371 QUALS are qualifiers indicating whether the function is `const'
9372 or `volatile'.
9373 RAISES is a list of exceptions that this function can raise.
9374 CHECK is 1 if we must find this method in CTYPE, 0 if we should
9375 not look, and -1 if we should not call `grokclassfn' at all.
9376
9377 SFK is the kind of special function (if any) for the new function.
9378
9379 Returns `NULL_TREE' if something goes wrong, after issuing
9380 applicable error messages. */
9381
9382 static tree
grokfndecl(tree ctype,tree type,tree declarator,tree parms,tree orig_declarator,const cp_decl_specifier_seq * declspecs,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,bool late_return_type_p,int initialized,int template_count,tree in_namespace,tree * attrlist,location_t location)9383 grokfndecl (tree ctype,
9384 tree type,
9385 tree declarator,
9386 tree parms,
9387 tree orig_declarator,
9388 const cp_decl_specifier_seq *declspecs,
9389 tree decl_reqs,
9390 int virtualp,
9391 enum overload_flags flags,
9392 cp_cv_quals quals,
9393 cp_ref_qualifier rqual,
9394 tree raises,
9395 int check,
9396 int friendp,
9397 int publicp,
9398 int inlinep,
9399 bool deletedp,
9400 special_function_kind sfk,
9401 bool funcdef_flag,
9402 bool late_return_type_p,
9403 int initialized,
9404 int template_count,
9405 tree in_namespace,
9406 tree* attrlist,
9407 location_t location)
9408 {
9409 tree decl;
9410 int staticp = ctype && TREE_CODE (type) == FUNCTION_TYPE;
9411 tree t;
9412
9413 if (location == UNKNOWN_LOCATION)
9414 location = input_location;
9415
9416 /* Was the concept specifier present? */
9417 bool concept_p = inlinep & 4;
9418
9419 /* Concept declarations must have a corresponding definition. */
9420 if (concept_p && !funcdef_flag)
9421 {
9422 error_at (location, "concept %qD has no definition", declarator);
9423 return NULL_TREE;
9424 }
9425
9426 type = build_cp_fntype_variant (type, rqual, raises, late_return_type_p);
9427
9428 decl = build_lang_decl_loc (location, FUNCTION_DECL, declarator, type);
9429
9430 /* Set the constraints on the declaration. */
9431 if (flag_concepts)
9432 {
9433 tree tmpl_reqs = NULL_TREE;
9434 tree ctx = friendp ? current_class_type : ctype;
9435 bool memtmpl = (processing_template_decl > template_class_depth (ctx));
9436 if (memtmpl)
9437 tmpl_reqs = TEMPLATE_PARMS_CONSTRAINTS (current_template_parms);
9438 tree ci = build_constraints (tmpl_reqs, decl_reqs);
9439 if (concept_p && ci)
9440 {
9441 error_at (location, "a function concept cannot be constrained");
9442 ci = NULL_TREE;
9443 }
9444 /* C++20 CA378: Remove non-templated constrained functions. */
9445 if (ci && !flag_concepts_ts
9446 && (!processing_template_decl
9447 || (friendp && !memtmpl && !initialized && !funcdef_flag)))
9448 {
9449 error_at (location, "constraints on a non-templated function");
9450 ci = NULL_TREE;
9451 }
9452 set_constraints (decl, ci);
9453 }
9454
9455 if (TREE_CODE (type) == METHOD_TYPE)
9456 {
9457 tree parm = build_this_parm (decl, type, quals);
9458 DECL_CHAIN (parm) = parms;
9459 parms = parm;
9460
9461 /* Allocate space to hold the vptr bit if needed. */
9462 SET_DECL_ALIGN (decl, MINIMUM_METHOD_BOUNDARY);
9463 }
9464
9465 DECL_ARGUMENTS (decl) = parms;
9466 for (t = parms; t; t = DECL_CHAIN (t))
9467 DECL_CONTEXT (t) = decl;
9468
9469 /* Propagate volatile out from type to decl. */
9470 if (TYPE_VOLATILE (type))
9471 TREE_THIS_VOLATILE (decl) = 1;
9472
9473 /* Setup decl according to sfk. */
9474 switch (sfk)
9475 {
9476 case sfk_constructor:
9477 case sfk_copy_constructor:
9478 case sfk_move_constructor:
9479 DECL_CXX_CONSTRUCTOR_P (decl) = 1;
9480 DECL_NAME (decl) = ctor_identifier;
9481 break;
9482 case sfk_destructor:
9483 DECL_CXX_DESTRUCTOR_P (decl) = 1;
9484 DECL_NAME (decl) = dtor_identifier;
9485 break;
9486 default:
9487 break;
9488 }
9489
9490 if (friendp && TREE_CODE (orig_declarator) == TEMPLATE_ID_EXPR)
9491 {
9492 if (funcdef_flag)
9493 error_at (location,
9494 "defining explicit specialization %qD in friend declaration",
9495 orig_declarator);
9496 else
9497 {
9498 tree fns = TREE_OPERAND (orig_declarator, 0);
9499 tree args = TREE_OPERAND (orig_declarator, 1);
9500
9501 if (PROCESSING_REAL_TEMPLATE_DECL_P ())
9502 {
9503 /* Something like `template <class T> friend void f<T>()'. */
9504 error_at (location,
9505 "invalid use of template-id %qD in declaration "
9506 "of primary template",
9507 orig_declarator);
9508 return NULL_TREE;
9509 }
9510
9511
9512 /* A friend declaration of the form friend void f<>(). Record
9513 the information in the TEMPLATE_ID_EXPR. */
9514 SET_DECL_IMPLICIT_INSTANTIATION (decl);
9515
9516 gcc_assert (identifier_p (fns) || OVL_P (fns));
9517 DECL_TEMPLATE_INFO (decl) = build_template_info (fns, args);
9518
9519 for (t = TYPE_ARG_TYPES (TREE_TYPE (decl)); t; t = TREE_CHAIN (t))
9520 if (TREE_PURPOSE (t)
9521 && TREE_CODE (TREE_PURPOSE (t)) == DEFERRED_PARSE)
9522 {
9523 error_at (defparse_location (TREE_PURPOSE (t)),
9524 "default arguments are not allowed in declaration "
9525 "of friend template specialization %qD",
9526 decl);
9527 return NULL_TREE;
9528 }
9529
9530 if (inlinep & 1)
9531 {
9532 error_at (declspecs->locations[ds_inline],
9533 "%<inline%> is not allowed in declaration of friend "
9534 "template specialization %qD",
9535 decl);
9536 return NULL_TREE;
9537 }
9538 }
9539 }
9540
9541 /* C++17 11.3.6/4: "If a friend declaration specifies a default argument
9542 expression, that declaration shall be a definition..." */
9543 if (friendp && !funcdef_flag)
9544 {
9545 for (tree t = FUNCTION_FIRST_USER_PARMTYPE (decl);
9546 t && t != void_list_node; t = TREE_CHAIN (t))
9547 if (TREE_PURPOSE (t))
9548 {
9549 permerror (DECL_SOURCE_LOCATION (decl),
9550 "friend declaration of %qD specifies default "
9551 "arguments and isn%'t a definition", decl);
9552 break;
9553 }
9554 }
9555
9556 /* FIXME: For now. */
9557 if (virtualp && (inlinep & 8) != 0)
9558 {
9559 sorry_at (DECL_SOURCE_LOCATION (decl),
9560 "%<virtual%> %<consteval%> method %qD not supported yet",
9561 decl);
9562 inlinep &= ~8;
9563 }
9564
9565 /* If this decl has namespace scope, set that up. */
9566 if (in_namespace)
9567 set_decl_namespace (decl, in_namespace, friendp);
9568 else if (!ctype)
9569 DECL_CONTEXT (decl) = FROB_CONTEXT (current_decl_namespace ());
9570
9571 /* `main' and builtins have implicit 'C' linkage. */
9572 if (ctype == NULL_TREE
9573 && DECL_FILE_SCOPE_P (decl)
9574 && current_lang_name == lang_name_cplusplus
9575 && (MAIN_NAME_P (declarator)
9576 || (IDENTIFIER_LENGTH (declarator) > 10
9577 && IDENTIFIER_POINTER (declarator)[0] == '_'
9578 && IDENTIFIER_POINTER (declarator)[1] == '_'
9579 && strncmp (IDENTIFIER_POINTER (declarator)+2,
9580 "builtin_", 8) == 0)
9581 || (targetcm.cxx_implicit_extern_c
9582 && (targetcm.cxx_implicit_extern_c
9583 (IDENTIFIER_POINTER (declarator))))))
9584 SET_DECL_LANGUAGE (decl, lang_c);
9585
9586 /* Should probably propagate const out from type to decl I bet (mrs). */
9587 if (staticp)
9588 {
9589 DECL_STATIC_FUNCTION_P (decl) = 1;
9590 DECL_CONTEXT (decl) = ctype;
9591 }
9592
9593 if (deletedp)
9594 DECL_DELETED_FN (decl) = 1;
9595
9596 if (ctype)
9597 {
9598 DECL_CONTEXT (decl) = ctype;
9599 if (funcdef_flag)
9600 check_class_member_definition_namespace (decl);
9601 }
9602
9603 if (ctype == NULL_TREE && DECL_MAIN_P (decl))
9604 {
9605 if (PROCESSING_REAL_TEMPLATE_DECL_P())
9606 error_at (location, "cannot declare %<::main%> to be a template");
9607 if (inlinep & 1)
9608 error_at (declspecs->locations[ds_inline],
9609 "cannot declare %<::main%> to be inline");
9610 if (inlinep & 2)
9611 error_at (declspecs->locations[ds_constexpr],
9612 "cannot declare %<::main%> to be %qs", "constexpr");
9613 if (inlinep & 8)
9614 error_at (declspecs->locations[ds_consteval],
9615 "cannot declare %<::main%> to be %qs", "consteval");
9616 if (!publicp)
9617 error_at (location, "cannot declare %<::main%> to be static");
9618 inlinep = 0;
9619 publicp = 1;
9620 }
9621
9622 /* Members of anonymous types and local classes have no linkage; make
9623 them internal. If a typedef is made later, this will be changed. */
9624 if (ctype && (!TREE_PUBLIC (TYPE_MAIN_DECL (ctype))
9625 || decl_function_context (TYPE_MAIN_DECL (ctype))))
9626 publicp = 0;
9627
9628 if (publicp && cxx_dialect == cxx98)
9629 {
9630 /* [basic.link]: A name with no linkage (notably, the name of a class
9631 or enumeration declared in a local scope) shall not be used to
9632 declare an entity with linkage.
9633
9634 DR 757 relaxes this restriction for C++0x. */
9635 no_linkage_error (decl);
9636 }
9637
9638 TREE_PUBLIC (decl) = publicp;
9639 if (! publicp)
9640 {
9641 DECL_INTERFACE_KNOWN (decl) = 1;
9642 DECL_NOT_REALLY_EXTERN (decl) = 1;
9643 }
9644
9645 /* If the declaration was declared inline, mark it as such. */
9646 if (inlinep)
9647 {
9648 DECL_DECLARED_INLINE_P (decl) = 1;
9649 if (publicp)
9650 DECL_COMDAT (decl) = 1;
9651 }
9652 if (inlinep & 2)
9653 DECL_DECLARED_CONSTEXPR_P (decl) = true;
9654 else if (inlinep & 8)
9655 {
9656 DECL_DECLARED_CONSTEXPR_P (decl) = true;
9657 SET_DECL_IMMEDIATE_FUNCTION_P (decl);
9658 }
9659
9660 // If the concept declaration specifier was found, check
9661 // that the declaration satisfies the necessary requirements.
9662 if (concept_p)
9663 {
9664 DECL_DECLARED_CONCEPT_P (decl) = true;
9665 check_concept_fn (decl);
9666 }
9667
9668 DECL_EXTERNAL (decl) = 1;
9669 if (TREE_CODE (type) == FUNCTION_TYPE)
9670 {
9671 if (quals || rqual)
9672 TREE_TYPE (decl) = apply_memfn_quals (TREE_TYPE (decl),
9673 TYPE_UNQUALIFIED,
9674 REF_QUAL_NONE);
9675
9676 if (quals)
9677 {
9678 error (ctype
9679 ? G_("static member function %qD cannot have cv-qualifier")
9680 : G_("non-member function %qD cannot have cv-qualifier"),
9681 decl);
9682 quals = TYPE_UNQUALIFIED;
9683 }
9684
9685 if (rqual)
9686 {
9687 error (ctype
9688 ? G_("static member function %qD cannot have ref-qualifier")
9689 : G_("non-member function %qD cannot have ref-qualifier"),
9690 decl);
9691 rqual = REF_QUAL_NONE;
9692 }
9693 }
9694
9695 if (deduction_guide_p (decl))
9696 {
9697 if (!DECL_NAMESPACE_SCOPE_P (decl))
9698 {
9699 error_at (location, "deduction guide %qD must be declared at "
9700 "namespace scope", decl);
9701 return NULL_TREE;
9702 }
9703 tree type = TREE_TYPE (DECL_NAME (decl));
9704 if (in_namespace == NULL_TREE
9705 && CP_DECL_CONTEXT (decl) != CP_TYPE_CONTEXT (type))
9706 {
9707 error_at (location, "deduction guide %qD must be declared in the "
9708 "same scope as %qT", decl, type);
9709 inform (location_of (type), " declared here");
9710 return NULL_TREE;
9711 }
9712 if (funcdef_flag)
9713 error_at (location,
9714 "deduction guide %qD must not have a function body", decl);
9715 }
9716 else if (IDENTIFIER_ANY_OP_P (DECL_NAME (decl))
9717 && !grok_op_properties (decl, /*complain=*/true))
9718 return NULL_TREE;
9719 else if (UDLIT_OPER_P (DECL_NAME (decl)))
9720 {
9721 bool long_long_unsigned_p;
9722 bool long_double_p;
9723 const char *suffix = NULL;
9724 /* [over.literal]/6: Literal operators shall not have C linkage. */
9725 if (DECL_LANGUAGE (decl) == lang_c)
9726 {
9727 error_at (location, "literal operator with C linkage");
9728 maybe_show_extern_c_location ();
9729 return NULL_TREE;
9730 }
9731
9732 if (DECL_NAMESPACE_SCOPE_P (decl))
9733 {
9734 if (!check_literal_operator_args (decl, &long_long_unsigned_p,
9735 &long_double_p))
9736 {
9737 error_at (location, "%qD has invalid argument list", decl);
9738 return NULL_TREE;
9739 }
9740
9741 suffix = UDLIT_OP_SUFFIX (DECL_NAME (decl));
9742 if (long_long_unsigned_p)
9743 {
9744 if (cpp_interpret_int_suffix (parse_in, suffix, strlen (suffix)))
9745 warning_at (location, 0, "integer suffix %qs"
9746 " shadowed by implementation", suffix);
9747 }
9748 else if (long_double_p)
9749 {
9750 if (cpp_interpret_float_suffix (parse_in, suffix, strlen (suffix)))
9751 warning_at (location, 0, "floating-point suffix %qs"
9752 " shadowed by implementation", suffix);
9753 }
9754 /* 17.6.3.3.5 */
9755 if (suffix[0] != '_'
9756 && !current_function_decl && !(friendp && !funcdef_flag))
9757 warning_at (location, OPT_Wliteral_suffix,
9758 "literal operator suffixes not preceded by %<_%>"
9759 " are reserved for future standardization");
9760 }
9761 else
9762 {
9763 error_at (location, "%qD must be a non-member function", decl);
9764 return NULL_TREE;
9765 }
9766 }
9767
9768 if (funcdef_flag)
9769 /* Make the init_value nonzero so pushdecl knows this is not
9770 tentative. error_mark_node is replaced later with the BLOCK. */
9771 DECL_INITIAL (decl) = error_mark_node;
9772
9773 if (TYPE_NOTHROW_P (type) || nothrow_libfn_p (decl))
9774 TREE_NOTHROW (decl) = 1;
9775
9776 if (flag_openmp || flag_openmp_simd)
9777 {
9778 /* Adjust "omp declare simd" attributes. */
9779 tree ods = lookup_attribute ("omp declare simd", *attrlist);
9780 if (ods)
9781 {
9782 tree attr;
9783 for (attr = ods; attr;
9784 attr = lookup_attribute ("omp declare simd", TREE_CHAIN (attr)))
9785 {
9786 if (TREE_CODE (type) == METHOD_TYPE)
9787 walk_tree (&TREE_VALUE (attr), declare_simd_adjust_this,
9788 DECL_ARGUMENTS (decl), NULL);
9789 if (TREE_VALUE (attr) != NULL_TREE)
9790 {
9791 tree cl = TREE_VALUE (TREE_VALUE (attr));
9792 cl = c_omp_declare_simd_clauses_to_numbers
9793 (DECL_ARGUMENTS (decl), cl);
9794 if (cl)
9795 TREE_VALUE (TREE_VALUE (attr)) = cl;
9796 else
9797 TREE_VALUE (attr) = NULL_TREE;
9798 }
9799 }
9800 }
9801 }
9802
9803 /* Caller will do the rest of this. */
9804 if (check < 0)
9805 return decl;
9806
9807 if (ctype != NULL_TREE)
9808 grokclassfn (ctype, decl, flags);
9809
9810 /* 12.4/3 */
9811 if (cxx_dialect >= cxx11
9812 && DECL_DESTRUCTOR_P (decl)
9813 && !TYPE_BEING_DEFINED (DECL_CONTEXT (decl))
9814 && !processing_template_decl)
9815 deduce_noexcept_on_destructor (decl);
9816
9817 decl = check_explicit_specialization (orig_declarator, decl,
9818 template_count,
9819 2 * funcdef_flag +
9820 4 * (friendp != 0) +
9821 8 * concept_p,
9822 *attrlist);
9823 if (decl == error_mark_node)
9824 return NULL_TREE;
9825
9826 if (DECL_STATIC_FUNCTION_P (decl))
9827 check_static_quals (decl, quals);
9828
9829 if (attrlist)
9830 {
9831 cplus_decl_attributes (&decl, *attrlist, 0);
9832 *attrlist = NULL_TREE;
9833 }
9834
9835 /* Check main's type after attributes have been applied. */
9836 if (ctype == NULL_TREE && DECL_MAIN_P (decl))
9837 {
9838 if (!same_type_p (TREE_TYPE (TREE_TYPE (decl)),
9839 integer_type_node))
9840 {
9841 tree oldtypeargs = TYPE_ARG_TYPES (TREE_TYPE (decl));
9842 tree newtype;
9843 error_at (declspecs->locations[ds_type_spec],
9844 "%<::main%> must return %<int%>");
9845 newtype = build_function_type (integer_type_node, oldtypeargs);
9846 TREE_TYPE (decl) = newtype;
9847 }
9848 if (warn_main)
9849 check_main_parameter_types (decl);
9850 }
9851
9852 if (ctype != NULL_TREE && check)
9853 {
9854 tree old_decl = check_classfn (ctype, decl,
9855 (processing_template_decl
9856 > template_class_depth (ctype))
9857 ? current_template_parms
9858 : NULL_TREE);
9859
9860 if (old_decl == error_mark_node)
9861 return NULL_TREE;
9862
9863 if (old_decl)
9864 {
9865 tree ok;
9866 tree pushed_scope;
9867
9868 if (TREE_CODE (old_decl) == TEMPLATE_DECL)
9869 /* Because grokfndecl is always supposed to return a
9870 FUNCTION_DECL, we pull out the DECL_TEMPLATE_RESULT
9871 here. We depend on our callers to figure out that its
9872 really a template that's being returned. */
9873 old_decl = DECL_TEMPLATE_RESULT (old_decl);
9874
9875 if (DECL_STATIC_FUNCTION_P (old_decl)
9876 && TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE)
9877 {
9878 /* Remove the `this' parm added by grokclassfn. */
9879 revert_static_member_fn (decl);
9880 check_static_quals (decl, quals);
9881 }
9882 if (DECL_ARTIFICIAL (old_decl))
9883 {
9884 error ("definition of implicitly-declared %qD", old_decl);
9885 return NULL_TREE;
9886 }
9887 else if (DECL_DEFAULTED_FN (old_decl))
9888 {
9889 error ("definition of explicitly-defaulted %q+D", decl);
9890 inform (DECL_SOURCE_LOCATION (old_decl),
9891 "%q#D explicitly defaulted here", old_decl);
9892 return NULL_TREE;
9893 }
9894
9895 /* Since we've smashed OLD_DECL to its
9896 DECL_TEMPLATE_RESULT, we must do the same to DECL. */
9897 if (TREE_CODE (decl) == TEMPLATE_DECL)
9898 decl = DECL_TEMPLATE_RESULT (decl);
9899
9900 /* Attempt to merge the declarations. This can fail, in
9901 the case of some invalid specialization declarations. */
9902 pushed_scope = push_scope (ctype);
9903 ok = duplicate_decls (decl, old_decl, friendp);
9904 if (pushed_scope)
9905 pop_scope (pushed_scope);
9906 if (!ok)
9907 {
9908 error ("no %q#D member function declared in class %qT",
9909 decl, ctype);
9910 return NULL_TREE;
9911 }
9912 if (ok == error_mark_node)
9913 return NULL_TREE;
9914 return old_decl;
9915 }
9916 }
9917
9918 if (DECL_CONSTRUCTOR_P (decl) && !grok_ctor_properties (ctype, decl))
9919 return NULL_TREE;
9920
9921 if (ctype == NULL_TREE || check)
9922 return decl;
9923
9924 if (virtualp)
9925 DECL_VIRTUAL_P (decl) = 1;
9926
9927 return decl;
9928 }
9929
9930 /* decl is a FUNCTION_DECL.
9931 specifiers are the parsed virt-specifiers.
9932
9933 Set flags to reflect the virt-specifiers.
9934
9935 Returns decl. */
9936
9937 static tree
set_virt_specifiers(tree decl,cp_virt_specifiers specifiers)9938 set_virt_specifiers (tree decl, cp_virt_specifiers specifiers)
9939 {
9940 if (decl == NULL_TREE)
9941 return decl;
9942 if (specifiers & VIRT_SPEC_OVERRIDE)
9943 DECL_OVERRIDE_P (decl) = 1;
9944 if (specifiers & VIRT_SPEC_FINAL)
9945 DECL_FINAL_P (decl) = 1;
9946 return decl;
9947 }
9948
9949 /* DECL is a VAR_DECL for a static data member. Set flags to reflect
9950 the linkage that DECL will receive in the object file. */
9951
9952 static void
set_linkage_for_static_data_member(tree decl)9953 set_linkage_for_static_data_member (tree decl)
9954 {
9955 /* A static data member always has static storage duration and
9956 external linkage. Note that static data members are forbidden in
9957 local classes -- the only situation in which a class has
9958 non-external linkage. */
9959 TREE_PUBLIC (decl) = 1;
9960 TREE_STATIC (decl) = 1;
9961 /* For non-template classes, static data members are always put
9962 out in exactly those files where they are defined, just as
9963 with ordinary namespace-scope variables. */
9964 if (!processing_template_decl)
9965 DECL_INTERFACE_KNOWN (decl) = 1;
9966 }
9967
9968 /* Create a VAR_DECL named NAME with the indicated TYPE.
9969
9970 If SCOPE is non-NULL, it is the class type or namespace containing
9971 the variable. If SCOPE is NULL, the variable should is created in
9972 the innermost enclosing scope. */
9973
9974 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,location_t location)9975 grokvardecl (tree type,
9976 tree name,
9977 tree orig_declarator,
9978 const cp_decl_specifier_seq *declspecs,
9979 int initialized,
9980 int type_quals,
9981 int inlinep,
9982 bool conceptp,
9983 int template_count,
9984 tree scope,
9985 location_t location)
9986 {
9987 tree decl;
9988 tree explicit_scope;
9989
9990 gcc_assert (!name || identifier_p (name));
9991
9992 bool constp = (type_quals & TYPE_QUAL_CONST) != 0;
9993 bool volatilep = (type_quals & TYPE_QUAL_VOLATILE) != 0;
9994
9995 /* Compute the scope in which to place the variable, but remember
9996 whether or not that scope was explicitly specified by the user. */
9997 explicit_scope = scope;
9998 if (!scope)
9999 {
10000 /* An explicit "extern" specifier indicates a namespace-scope
10001 variable. */
10002 if (declspecs->storage_class == sc_extern)
10003 scope = current_decl_namespace ();
10004 else if (!at_function_scope_p ())
10005 scope = current_scope ();
10006 }
10007
10008 if (scope
10009 && (/* If the variable is a namespace-scope variable declared in a
10010 template, we need DECL_LANG_SPECIFIC. */
10011 (TREE_CODE (scope) == NAMESPACE_DECL && processing_template_decl)
10012 /* Similarly for namespace-scope variables with language linkage
10013 other than C++. */
10014 || (TREE_CODE (scope) == NAMESPACE_DECL
10015 && current_lang_name != lang_name_cplusplus)
10016 /* Similarly for static data members. */
10017 || TYPE_P (scope)
10018 /* Similarly for explicit specializations. */
10019 || (orig_declarator
10020 && TREE_CODE (orig_declarator) == TEMPLATE_ID_EXPR)))
10021 decl = build_lang_decl_loc (location, VAR_DECL, name, type);
10022 else
10023 decl = build_decl (location, VAR_DECL, name, type);
10024
10025 if (explicit_scope && TREE_CODE (explicit_scope) == NAMESPACE_DECL)
10026 set_decl_namespace (decl, explicit_scope, 0);
10027 else
10028 DECL_CONTEXT (decl) = FROB_CONTEXT (scope);
10029
10030 if (declspecs->storage_class == sc_extern)
10031 {
10032 DECL_THIS_EXTERN (decl) = 1;
10033 DECL_EXTERNAL (decl) = !initialized;
10034 }
10035
10036 if (DECL_CLASS_SCOPE_P (decl))
10037 {
10038 set_linkage_for_static_data_member (decl);
10039 /* This function is only called with out-of-class definitions. */
10040 DECL_EXTERNAL (decl) = 0;
10041 check_class_member_definition_namespace (decl);
10042 }
10043 /* At top level, either `static' or no s.c. makes a definition
10044 (perhaps tentative), and absence of `static' makes it public. */
10045 else if (toplevel_bindings_p ())
10046 {
10047 TREE_PUBLIC (decl) = (declspecs->storage_class != sc_static
10048 && (DECL_THIS_EXTERN (decl)
10049 || ! constp
10050 || volatilep
10051 || inlinep));
10052 TREE_STATIC (decl) = ! DECL_EXTERNAL (decl);
10053 }
10054 /* Not at top level, only `static' makes a static definition. */
10055 else
10056 {
10057 TREE_STATIC (decl) = declspecs->storage_class == sc_static;
10058 TREE_PUBLIC (decl) = DECL_EXTERNAL (decl);
10059 }
10060
10061 if (decl_spec_seq_has_spec_p (declspecs, ds_thread))
10062 {
10063 if (DECL_EXTERNAL (decl) || TREE_STATIC (decl))
10064 {
10065 CP_DECL_THREAD_LOCAL_P (decl) = true;
10066 if (!processing_template_decl)
10067 set_decl_tls_model (decl, decl_default_tls_model (decl));
10068 }
10069 if (declspecs->gnu_thread_keyword_p)
10070 SET_DECL_GNU_TLS_P (decl);
10071 }
10072
10073 /* If the type of the decl has no linkage, make sure that we'll
10074 notice that in mark_used. */
10075 if (cxx_dialect > cxx98
10076 && decl_linkage (decl) != lk_none
10077 && DECL_LANG_SPECIFIC (decl) == NULL
10078 && !DECL_EXTERN_C_P (decl)
10079 && no_linkage_check (TREE_TYPE (decl), /*relaxed_p=*/false))
10080 retrofit_lang_decl (decl);
10081
10082 if (TREE_PUBLIC (decl))
10083 {
10084 /* [basic.link]: A name with no linkage (notably, the name of a class
10085 or enumeration declared in a local scope) shall not be used to
10086 declare an entity with linkage.
10087
10088 DR 757 relaxes this restriction for C++0x. */
10089 if (cxx_dialect < cxx11)
10090 no_linkage_error (decl);
10091 }
10092 else
10093 DECL_INTERFACE_KNOWN (decl) = 1;
10094
10095 if (DECL_NAME (decl)
10096 && MAIN_NAME_P (DECL_NAME (decl))
10097 && scope == global_namespace)
10098 error_at (DECL_SOURCE_LOCATION (decl),
10099 "cannot declare %<::main%> to be a global variable");
10100
10101 /* Check that the variable can be safely declared as a concept.
10102 Note that this also forbids explicit specializations. */
10103 if (conceptp)
10104 {
10105 if (!processing_template_decl)
10106 {
10107 error_at (declspecs->locations[ds_concept],
10108 "a non-template variable cannot be %<concept%>");
10109 return NULL_TREE;
10110 }
10111 else
10112 DECL_DECLARED_CONCEPT_P (decl) = true;
10113 if (!same_type_ignoring_top_level_qualifiers_p (type, boolean_type_node))
10114 error_at (declspecs->locations[ds_type_spec],
10115 "concept must have type %<bool%>");
10116 if (TEMPLATE_PARMS_CONSTRAINTS (current_template_parms))
10117 {
10118 error_at (location, "a variable concept cannot be constrained");
10119 TEMPLATE_PARMS_CONSTRAINTS (current_template_parms) = NULL_TREE;
10120 }
10121 }
10122 else if (flag_concepts
10123 && processing_template_decl > template_class_depth (scope))
10124 {
10125 tree reqs = TEMPLATE_PARMS_CONSTRAINTS (current_template_parms);
10126 tree ci = build_constraints (reqs, NULL_TREE);
10127
10128 set_constraints (decl, ci);
10129 }
10130
10131 // Handle explicit specializations and instantiations of variable templates.
10132 if (orig_declarator)
10133 decl = check_explicit_specialization (orig_declarator, decl,
10134 template_count, conceptp * 8);
10135
10136 return decl != error_mark_node ? decl : NULL_TREE;
10137 }
10138
10139 /* Create and return a canonical pointer to member function type, for
10140 TYPE, which is a POINTER_TYPE to a METHOD_TYPE. */
10141
10142 tree
build_ptrmemfunc_type(tree type)10143 build_ptrmemfunc_type (tree type)
10144 {
10145 tree field, fields;
10146 tree t;
10147
10148 if (type == error_mark_node)
10149 return type;
10150
10151 /* Make sure that we always have the unqualified pointer-to-member
10152 type first. */
10153 if (cp_cv_quals quals = cp_type_quals (type))
10154 {
10155 tree unqual = build_ptrmemfunc_type (TYPE_MAIN_VARIANT (type));
10156 return cp_build_qualified_type (unqual, quals);
10157 }
10158
10159 /* If a canonical type already exists for this type, use it. We use
10160 this method instead of type_hash_canon, because it only does a
10161 simple equality check on the list of field members. */
10162
10163 t = TYPE_PTRMEMFUNC_TYPE (type);
10164 if (t)
10165 return t;
10166
10167 t = make_node (RECORD_TYPE);
10168
10169 /* Let the front end know this is a pointer to member function. */
10170 TYPE_PTRMEMFUNC_FLAG (t) = 1;
10171
10172 field = build_decl (input_location, FIELD_DECL, pfn_identifier, type);
10173 DECL_NONADDRESSABLE_P (field) = 1;
10174 fields = field;
10175
10176 field = build_decl (input_location, FIELD_DECL, delta_identifier,
10177 delta_type_node);
10178 DECL_NONADDRESSABLE_P (field) = 1;
10179 DECL_CHAIN (field) = fields;
10180 fields = field;
10181
10182 finish_builtin_struct (t, "__ptrmemfunc_type", fields, ptr_type_node);
10183
10184 /* Zap out the name so that the back end will give us the debugging
10185 information for this anonymous RECORD_TYPE. */
10186 TYPE_NAME (t) = NULL_TREE;
10187
10188 /* Cache this pointer-to-member type so that we can find it again
10189 later. */
10190 TYPE_PTRMEMFUNC_TYPE (type) = t;
10191
10192 if (TYPE_STRUCTURAL_EQUALITY_P (type))
10193 SET_TYPE_STRUCTURAL_EQUALITY (t);
10194 else if (TYPE_CANONICAL (type) != type)
10195 TYPE_CANONICAL (t) = build_ptrmemfunc_type (TYPE_CANONICAL (type));
10196
10197 return t;
10198 }
10199
10200 /* Create and return a pointer to data member type. */
10201
10202 tree
build_ptrmem_type(tree class_type,tree member_type)10203 build_ptrmem_type (tree class_type, tree member_type)
10204 {
10205 if (TREE_CODE (member_type) == METHOD_TYPE)
10206 {
10207 cp_cv_quals quals = type_memfn_quals (member_type);
10208 cp_ref_qualifier rqual = type_memfn_rqual (member_type);
10209 member_type = build_memfn_type (member_type, class_type, quals, rqual);
10210 return build_ptrmemfunc_type (build_pointer_type (member_type));
10211 }
10212 else
10213 {
10214 gcc_assert (TREE_CODE (member_type) != FUNCTION_TYPE);
10215 return build_offset_type (class_type, member_type);
10216 }
10217 }
10218
10219 /* DECL is a VAR_DECL defined in-class, whose TYPE is also given.
10220 Check to see that the definition is valid. Issue appropriate error
10221 messages. */
10222
10223 static void
check_static_variable_definition(tree decl,tree type)10224 check_static_variable_definition (tree decl, tree type)
10225 {
10226 /* Avoid redundant diagnostics on out-of-class definitions. */
10227 if (!current_class_type || !TYPE_BEING_DEFINED (current_class_type))
10228 ;
10229 /* Can't check yet if we don't know the type. */
10230 else if (dependent_type_p (type))
10231 ;
10232 /* If DECL is declared constexpr, we'll do the appropriate checks
10233 in check_initializer. Similarly for inline static data members. */
10234 else if (DECL_P (decl)
10235 && (DECL_DECLARED_CONSTEXPR_P (decl)
10236 || undeduced_auto_decl (decl)
10237 || DECL_VAR_DECLARED_INLINE_P (decl)))
10238 ;
10239 else if (cxx_dialect >= cxx11 && !INTEGRAL_OR_ENUMERATION_TYPE_P (type))
10240 {
10241 if (!COMPLETE_TYPE_P (type))
10242 error_at (DECL_SOURCE_LOCATION (decl),
10243 "in-class initialization of static data member %q#D of "
10244 "incomplete type", decl);
10245 else if (literal_type_p (type))
10246 permerror (DECL_SOURCE_LOCATION (decl),
10247 "%<constexpr%> needed for in-class initialization of "
10248 "static data member %q#D of non-integral type", decl);
10249 else
10250 error_at (DECL_SOURCE_LOCATION (decl),
10251 "in-class initialization of static data member %q#D of "
10252 "non-literal type", decl);
10253 }
10254 /* Motion 10 at San Diego: If a static const integral data member is
10255 initialized with an integral constant expression, the initializer
10256 may appear either in the declaration (within the class), or in
10257 the definition, but not both. If it appears in the class, the
10258 member is a member constant. The file-scope definition is always
10259 required. */
10260 else if (!ARITHMETIC_TYPE_P (type) && TREE_CODE (type) != ENUMERAL_TYPE)
10261 error_at (DECL_SOURCE_LOCATION (decl),
10262 "invalid in-class initialization of static data member "
10263 "of non-integral type %qT",
10264 type);
10265 else if (!CP_TYPE_CONST_P (type))
10266 error_at (DECL_SOURCE_LOCATION (decl),
10267 "ISO C++ forbids in-class initialization of non-const "
10268 "static member %qD",
10269 decl);
10270 else if (!INTEGRAL_OR_ENUMERATION_TYPE_P (type))
10271 pedwarn (DECL_SOURCE_LOCATION (decl), OPT_Wpedantic,
10272 "ISO C++ forbids initialization of member constant "
10273 "%qD of non-integral type %qT", decl, type);
10274 }
10275
10276 /* *expr_p is part of the TYPE_SIZE of a variably-sized array. If any
10277 SAVE_EXPRs in *expr_p wrap expressions with side-effects, break those
10278 expressions out into temporary variables so that walk_tree doesn't
10279 step into them (c++/15764). */
10280
10281 static tree
stabilize_save_expr_r(tree * expr_p,int * walk_subtrees,void * data)10282 stabilize_save_expr_r (tree *expr_p, int *walk_subtrees, void *data)
10283 {
10284 hash_set<tree> *pset = (hash_set<tree> *)data;
10285 tree expr = *expr_p;
10286 if (TREE_CODE (expr) == SAVE_EXPR)
10287 {
10288 tree op = TREE_OPERAND (expr, 0);
10289 cp_walk_tree (&op, stabilize_save_expr_r, data, pset);
10290 if (TREE_SIDE_EFFECTS (op))
10291 TREE_OPERAND (expr, 0) = get_temp_regvar (TREE_TYPE (op), op);
10292 *walk_subtrees = 0;
10293 }
10294 else if (!EXPR_P (expr) || !TREE_SIDE_EFFECTS (expr))
10295 *walk_subtrees = 0;
10296 return NULL;
10297 }
10298
10299 /* Entry point for the above. */
10300
10301 static void
stabilize_vla_size(tree size)10302 stabilize_vla_size (tree size)
10303 {
10304 hash_set<tree> pset;
10305 /* Break out any function calls into temporary variables. */
10306 cp_walk_tree (&size, stabilize_save_expr_r, &pset, &pset);
10307 }
10308
10309 /* Reduce a SIZEOF_EXPR to its value. */
10310
10311 tree
fold_sizeof_expr(tree t)10312 fold_sizeof_expr (tree t)
10313 {
10314 tree r;
10315 if (SIZEOF_EXPR_TYPE_P (t))
10316 r = cxx_sizeof_or_alignof_type (EXPR_LOCATION (t),
10317 TREE_TYPE (TREE_OPERAND (t, 0)),
10318 SIZEOF_EXPR, false, false);
10319 else if (TYPE_P (TREE_OPERAND (t, 0)))
10320 r = cxx_sizeof_or_alignof_type (EXPR_LOCATION (t),
10321 TREE_OPERAND (t, 0), SIZEOF_EXPR,
10322 false, false);
10323 else
10324 r = cxx_sizeof_or_alignof_expr (EXPR_LOCATION (t),
10325 TREE_OPERAND (t, 0), SIZEOF_EXPR,
10326 false);
10327 if (r == error_mark_node)
10328 r = size_one_node;
10329 return r;
10330 }
10331
10332 /* Given the SIZE (i.e., number of elements) in an array, compute
10333 an appropriate index type for the array. If non-NULL, NAME is
10334 the name of the entity being declared. */
10335
10336 static tree
compute_array_index_type_loc(location_t name_loc,tree name,tree size,tsubst_flags_t complain)10337 compute_array_index_type_loc (location_t name_loc, tree name, tree size,
10338 tsubst_flags_t complain)
10339 {
10340 if (error_operand_p (size))
10341 return error_mark_node;
10342
10343 /* The type of the index being computed. */
10344 tree itype;
10345
10346 /* The original numeric size as seen in the source code before
10347 conversion to size_t. */
10348 tree origsize = size;
10349
10350 location_t loc = cp_expr_loc_or_loc (size, name ? name_loc : input_location);
10351
10352 if (!type_dependent_expression_p (size))
10353 {
10354 origsize = size = mark_rvalue_use (size);
10355
10356 if (cxx_dialect < cxx11 && TREE_CODE (size) == NOP_EXPR
10357 && TREE_SIDE_EFFECTS (size))
10358 /* In C++98, we mark a non-constant array bound with a magic
10359 NOP_EXPR with TREE_SIDE_EFFECTS; don't fold in that case. */;
10360 else
10361 {
10362 size = build_converted_constant_expr (size_type_node, size, complain);
10363 /* Pedantically a constant expression is required here and so
10364 __builtin_is_constant_evaluated () should fold to true if it
10365 is successfully folded into a constant. */
10366 size = fold_non_dependent_expr (size, complain,
10367 /*manifestly_const_eval=*/true);
10368
10369 if (!TREE_CONSTANT (size))
10370 size = origsize;
10371 }
10372
10373 if (error_operand_p (size))
10374 return error_mark_node;
10375
10376 /* The array bound must be an integer type. */
10377 tree type = TREE_TYPE (size);
10378 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (type))
10379 {
10380 if (!(complain & tf_error))
10381 return error_mark_node;
10382 if (name)
10383 error_at (loc, "size of array %qD has non-integral type %qT",
10384 name, type);
10385 else
10386 error_at (loc, "size of array has non-integral type %qT", type);
10387 size = integer_one_node;
10388 }
10389 }
10390
10391 /* A type is dependent if it is...an array type constructed from any
10392 dependent type or whose size is specified by a constant expression
10393 that is value-dependent. */
10394 /* We can only call value_dependent_expression_p on integral constant
10395 expressions; treat non-constant expressions as dependent, too. */
10396 if (processing_template_decl
10397 && (!TREE_CONSTANT (size) || value_dependent_expression_p (size)))
10398 {
10399 /* We cannot do any checking for a SIZE that isn't known to be
10400 constant. Just build the index type and mark that it requires
10401 structural equality checks. */
10402 itype = build_index_type (build_min (MINUS_EXPR, sizetype,
10403 size, size_one_node));
10404 TYPE_DEPENDENT_P (itype) = 1;
10405 TYPE_DEPENDENT_P_VALID (itype) = 1;
10406 SET_TYPE_STRUCTURAL_EQUALITY (itype);
10407 return itype;
10408 }
10409
10410 if (TREE_CODE (size) != INTEGER_CST)
10411 {
10412 tree folded = cp_fully_fold (size);
10413 if (TREE_CODE (folded) == INTEGER_CST)
10414 {
10415 if (name)
10416 pedwarn (loc, OPT_Wpedantic, "size of array %qD is not an "
10417 "integral constant-expression", name);
10418 else
10419 pedwarn (loc, OPT_Wpedantic,
10420 "size of array is not an integral constant-expression");
10421 }
10422 if (TREE_CONSTANT (size) && !TREE_CONSTANT (folded))
10423 /* We might have lost the TREE_CONSTANT flag e.g. when we are
10424 folding a conversion from a pointer to integral type. In that
10425 case issue an error below and don't treat this as a VLA. */;
10426 else
10427 /* Use the folded result for VLAs, too; it will have resolved
10428 SIZEOF_EXPR. */
10429 size = folded;
10430 }
10431
10432 /* Normally, the array-bound will be a constant. */
10433 if (TREE_CODE (size) == INTEGER_CST)
10434 {
10435 /* The size to use in diagnostics that reflects the constant
10436 size used in the source, rather than SIZE massaged above. */
10437 tree diagsize = size;
10438
10439 /* If the original size before conversion to size_t was signed
10440 and negative, convert it to ssizetype to restore the sign. */
10441 if (!TYPE_UNSIGNED (TREE_TYPE (origsize))
10442 && TREE_CODE (size) == INTEGER_CST
10443 && tree_int_cst_sign_bit (size))
10444 {
10445 diagsize = fold_convert (ssizetype, size);
10446
10447 /* Clear the overflow bit that may have been set as a result
10448 of the conversion from the sizetype of the new size to
10449 ssizetype. */
10450 TREE_OVERFLOW (diagsize) = false;
10451 }
10452
10453 /* Verify that the array has a positive number of elements
10454 and issue the appropriate diagnostic if it doesn't. */
10455 if (!valid_array_size_p (loc, diagsize, name, (complain & tf_error)))
10456 {
10457 if (!(complain & tf_error))
10458 return error_mark_node;
10459 size = integer_one_node;
10460 }
10461 /* As an extension we allow zero-sized arrays. */
10462 else if (integer_zerop (size))
10463 {
10464 if (!(complain & tf_error))
10465 /* We must fail if performing argument deduction (as
10466 indicated by the state of complain), so that
10467 another substitution can be found. */
10468 return error_mark_node;
10469 else if (name)
10470 pedwarn (loc, OPT_Wpedantic,
10471 "ISO C++ forbids zero-size array %qD", name);
10472 else
10473 pedwarn (loc, OPT_Wpedantic,
10474 "ISO C++ forbids zero-size array");
10475 }
10476 }
10477 else if (TREE_CONSTANT (size)
10478 /* We don't allow VLAs at non-function scopes, or during
10479 tentative template substitution. */
10480 || !at_function_scope_p ()
10481 || !(complain & tf_error))
10482 {
10483 if (!(complain & tf_error))
10484 return error_mark_node;
10485 /* `(int) &fn' is not a valid array bound. */
10486 if (name)
10487 error_at (loc,
10488 "size of array %qD is not an integral constant-expression",
10489 name);
10490 else
10491 error_at (loc, "size of array is not an integral constant-expression");
10492 size = integer_one_node;
10493 }
10494 else if (pedantic && warn_vla != 0)
10495 {
10496 if (name)
10497 pedwarn (name_loc, OPT_Wvla,
10498 "ISO C++ forbids variable length array %qD", name);
10499 else
10500 pedwarn (input_location, OPT_Wvla,
10501 "ISO C++ forbids variable length array");
10502 }
10503 else if (warn_vla > 0)
10504 {
10505 if (name)
10506 warning_at (name_loc, OPT_Wvla,
10507 "variable length array %qD is used", name);
10508 else
10509 warning (OPT_Wvla,
10510 "variable length array is used");
10511 }
10512
10513 if (processing_template_decl && !TREE_CONSTANT (size))
10514 /* A variable sized array. */
10515 itype = build_min (MINUS_EXPR, sizetype, size, integer_one_node);
10516 else
10517 {
10518 /* Compute the index of the largest element in the array. It is
10519 one less than the number of elements in the array. We save
10520 and restore PROCESSING_TEMPLATE_DECL so that computations in
10521 cp_build_binary_op will be appropriately folded. */
10522 {
10523 processing_template_decl_sentinel s;
10524 itype = cp_build_binary_op (input_location,
10525 MINUS_EXPR,
10526 cp_convert (ssizetype, size, complain),
10527 cp_convert (ssizetype, integer_one_node,
10528 complain),
10529 complain);
10530 itype = maybe_constant_value (itype);
10531 }
10532
10533 if (!TREE_CONSTANT (itype))
10534 {
10535 /* A variable sized array. */
10536 itype = variable_size (itype);
10537
10538 stabilize_vla_size (itype);
10539
10540 if (sanitize_flags_p (SANITIZE_VLA)
10541 && current_function_decl != NULL_TREE)
10542 {
10543 /* We have to add 1 -- in the ubsan routine we generate
10544 LE_EXPR rather than LT_EXPR. */
10545 tree t = fold_build2 (PLUS_EXPR, TREE_TYPE (itype), itype,
10546 build_one_cst (TREE_TYPE (itype)));
10547 t = ubsan_instrument_vla (input_location, t);
10548 finish_expr_stmt (t);
10549 }
10550 }
10551 /* Make sure that there was no overflow when creating to a signed
10552 index type. (For example, on a 32-bit machine, an array with
10553 size 2^32 - 1 is too big.) */
10554 else if (TREE_CODE (itype) == INTEGER_CST
10555 && TREE_OVERFLOW (itype))
10556 {
10557 if (!(complain & tf_error))
10558 return error_mark_node;
10559 error ("overflow in array dimension");
10560 TREE_OVERFLOW (itype) = 0;
10561 }
10562 }
10563
10564 /* Create and return the appropriate index type. */
10565 itype = build_index_type (itype);
10566
10567 /* If the index type were dependent, we would have returned early, so
10568 remember that it isn't. */
10569 TYPE_DEPENDENT_P (itype) = 0;
10570 TYPE_DEPENDENT_P_VALID (itype) = 1;
10571 return itype;
10572 }
10573
10574 tree
compute_array_index_type(tree name,tree size,tsubst_flags_t complain)10575 compute_array_index_type (tree name, tree size, tsubst_flags_t complain)
10576 {
10577 return compute_array_index_type_loc (input_location, name, size, complain);
10578 }
10579
10580 /* Returns the scope (if any) in which the entity declared by
10581 DECLARATOR will be located. If the entity was declared with an
10582 unqualified name, NULL_TREE is returned. */
10583
10584 tree
get_scope_of_declarator(const cp_declarator * declarator)10585 get_scope_of_declarator (const cp_declarator *declarator)
10586 {
10587 while (declarator && declarator->kind != cdk_id)
10588 declarator = declarator->declarator;
10589
10590 /* If the declarator-id is a SCOPE_REF, the scope in which the
10591 declaration occurs is the first operand. */
10592 if (declarator
10593 && declarator->u.id.qualifying_scope)
10594 return declarator->u.id.qualifying_scope;
10595
10596 /* Otherwise, the declarator is not a qualified name; the entity will
10597 be declared in the current scope. */
10598 return NULL_TREE;
10599 }
10600
10601 /* Returns an ARRAY_TYPE for an array with SIZE elements of the
10602 indicated TYPE. If non-NULL, NAME is the NAME of the declaration
10603 with this type. */
10604
10605 static tree
create_array_type_for_decl(tree name,tree type,tree size,location_t loc)10606 create_array_type_for_decl (tree name, tree type, tree size, location_t loc)
10607 {
10608 tree itype = NULL_TREE;
10609
10610 /* If things have already gone awry, bail now. */
10611 if (type == error_mark_node || size == error_mark_node)
10612 return error_mark_node;
10613
10614 /* 8.3.4/1: If the type of the identifier of D contains the auto
10615 type-specifier, the program is ill-formed. */
10616 if (type_uses_auto (type))
10617 {
10618 if (name)
10619 error_at (loc, "%qD declared as array of %qT", name, type);
10620 else
10621 error ("creating array of %qT", type);
10622 return error_mark_node;
10623 }
10624
10625 /* If there are some types which cannot be array elements,
10626 issue an error-message and return. */
10627 switch (TREE_CODE (type))
10628 {
10629 case VOID_TYPE:
10630 if (name)
10631 error_at (loc, "declaration of %qD as array of void", name);
10632 else
10633 error ("creating array of void");
10634 return error_mark_node;
10635
10636 case FUNCTION_TYPE:
10637 if (name)
10638 error_at (loc, "declaration of %qD as array of functions", name);
10639 else
10640 error ("creating array of functions");
10641 return error_mark_node;
10642
10643 case REFERENCE_TYPE:
10644 if (name)
10645 error_at (loc, "declaration of %qD as array of references", name);
10646 else
10647 error ("creating array of references");
10648 return error_mark_node;
10649
10650 case METHOD_TYPE:
10651 if (name)
10652 error_at (loc, "declaration of %qD as array of function members",
10653 name);
10654 else
10655 error ("creating array of function members");
10656 return error_mark_node;
10657
10658 default:
10659 break;
10660 }
10661
10662 if (!verify_type_context (name ? loc : input_location,
10663 TCTX_ARRAY_ELEMENT, type))
10664 return error_mark_node;
10665
10666 /* [dcl.array]
10667
10668 The constant expressions that specify the bounds of the arrays
10669 can be omitted only for the first member of the sequence. */
10670 if (TREE_CODE (type) == ARRAY_TYPE && !TYPE_DOMAIN (type))
10671 {
10672 if (name)
10673 error_at (loc, "declaration of %qD as multidimensional array must "
10674 "have bounds for all dimensions except the first",
10675 name);
10676 else
10677 error ("multidimensional array must have bounds for all "
10678 "dimensions except the first");
10679
10680 return error_mark_node;
10681 }
10682
10683 /* Figure out the index type for the array. */
10684 if (size)
10685 itype = compute_array_index_type_loc (loc, name, size,
10686 tf_warning_or_error);
10687
10688 /* [dcl.array]
10689 T is called the array element type; this type shall not be [...] an
10690 abstract class type. */
10691 abstract_virtuals_error (name, type);
10692
10693 return build_cplus_array_type (type, itype);
10694 }
10695
10696 /* Returns the smallest location that is not UNKNOWN_LOCATION. */
10697
10698 static location_t
min_location(location_t loca,location_t locb)10699 min_location (location_t loca, location_t locb)
10700 {
10701 if (loca == UNKNOWN_LOCATION
10702 || (locb != UNKNOWN_LOCATION
10703 && linemap_location_before_p (line_table, locb, loca)))
10704 return locb;
10705 return loca;
10706 }
10707
10708 /* Returns the smallest location != UNKNOWN_LOCATION among the
10709 three stored in LOCATIONS[ds_const], LOCATIONS[ds_volatile],
10710 and LOCATIONS[ds_restrict]. */
10711
10712 static location_t
smallest_type_quals_location(int type_quals,const location_t * locations)10713 smallest_type_quals_location (int type_quals, const location_t* locations)
10714 {
10715 location_t loc = UNKNOWN_LOCATION;
10716
10717 if (type_quals & TYPE_QUAL_CONST)
10718 loc = locations[ds_const];
10719
10720 if (type_quals & TYPE_QUAL_VOLATILE)
10721 loc = min_location (loc, locations[ds_volatile]);
10722
10723 if (type_quals & TYPE_QUAL_RESTRICT)
10724 loc = min_location (loc, locations[ds_restrict]);
10725
10726 return loc;
10727 }
10728
10729 /* Returns the smallest among the latter and locations[ds_type_spec]. */
10730
10731 static location_t
smallest_type_location(int type_quals,const location_t * locations)10732 smallest_type_location (int type_quals, const location_t* locations)
10733 {
10734 location_t loc = smallest_type_quals_location (type_quals, locations);
10735 return min_location (loc, locations[ds_type_spec]);
10736 }
10737
10738 static location_t
smallest_type_location(const cp_decl_specifier_seq * declspecs)10739 smallest_type_location (const cp_decl_specifier_seq *declspecs)
10740 {
10741 int type_quals = get_type_quals (declspecs);
10742 return smallest_type_location (type_quals, declspecs->locations);
10743 }
10744
10745 /* Check that it's OK to declare a function with the indicated TYPE
10746 and TYPE_QUALS. SFK indicates the kind of special function (if any)
10747 that this function is. OPTYPE is the type given in a conversion
10748 operator declaration, or the class type for a constructor/destructor.
10749 Returns the actual return type of the function; that may be different
10750 than TYPE if an error occurs, or for certain special functions. */
10751
10752 static tree
check_special_function_return_type(special_function_kind sfk,tree type,tree optype,int type_quals,const location_t * locations)10753 check_special_function_return_type (special_function_kind sfk,
10754 tree type,
10755 tree optype,
10756 int type_quals,
10757 const location_t* locations)
10758 {
10759 switch (sfk)
10760 {
10761 case sfk_constructor:
10762 if (type)
10763 error_at (smallest_type_location (type_quals, locations),
10764 "return type specification for constructor invalid");
10765 else if (type_quals != TYPE_UNQUALIFIED)
10766 error_at (smallest_type_quals_location (type_quals, locations),
10767 "qualifiers are not allowed on constructor declaration");
10768
10769 if (targetm.cxx.cdtor_returns_this ())
10770 type = build_pointer_type (optype);
10771 else
10772 type = void_type_node;
10773 break;
10774
10775 case sfk_destructor:
10776 if (type)
10777 error_at (smallest_type_location (type_quals, locations),
10778 "return type specification for destructor invalid");
10779 else if (type_quals != TYPE_UNQUALIFIED)
10780 error_at (smallest_type_quals_location (type_quals, locations),
10781 "qualifiers are not allowed on destructor declaration");
10782
10783 /* We can't use the proper return type here because we run into
10784 problems with ambiguous bases and covariant returns. */
10785 if (targetm.cxx.cdtor_returns_this ())
10786 type = build_pointer_type (void_type_node);
10787 else
10788 type = void_type_node;
10789 break;
10790
10791 case sfk_conversion:
10792 if (type)
10793 error_at (smallest_type_location (type_quals, locations),
10794 "return type specified for %<operator %T%>", optype);
10795 else if (type_quals != TYPE_UNQUALIFIED)
10796 error_at (smallest_type_quals_location (type_quals, locations),
10797 "qualifiers are not allowed on declaration of "
10798 "%<operator %T%>", optype);
10799
10800 type = optype;
10801 break;
10802
10803 case sfk_deduction_guide:
10804 if (type)
10805 error_at (smallest_type_location (type_quals, locations),
10806 "return type specified for deduction guide");
10807 else if (type_quals != TYPE_UNQUALIFIED)
10808 error_at (smallest_type_quals_location (type_quals, locations),
10809 "qualifiers are not allowed on declaration of "
10810 "deduction guide");
10811 if (TREE_CODE (optype) == TEMPLATE_TEMPLATE_PARM)
10812 {
10813 error ("template template parameter %qT in declaration of "
10814 "deduction guide", optype);
10815 type = error_mark_node;
10816 }
10817 else
10818 type = make_template_placeholder (CLASSTYPE_TI_TEMPLATE (optype));
10819 for (int i = 0; i < ds_last; ++i)
10820 if (i != ds_explicit && locations[i])
10821 error_at (locations[i],
10822 "%<decl-specifier%> in declaration of deduction guide");
10823 break;
10824
10825 default:
10826 gcc_unreachable ();
10827 }
10828
10829 return type;
10830 }
10831
10832 /* A variable or data member (whose unqualified name is IDENTIFIER)
10833 has been declared with the indicated TYPE. If the TYPE is not
10834 acceptable, issue an error message and return a type to use for
10835 error-recovery purposes. */
10836
10837 tree
check_var_type(tree identifier,tree type,location_t loc)10838 check_var_type (tree identifier, tree type, location_t loc)
10839 {
10840 if (VOID_TYPE_P (type))
10841 {
10842 if (!identifier)
10843 error_at (loc, "unnamed variable or field declared void");
10844 else if (identifier_p (identifier))
10845 {
10846 gcc_assert (!IDENTIFIER_ANY_OP_P (identifier));
10847 error_at (loc, "variable or field %qE declared void",
10848 identifier);
10849 }
10850 else
10851 error_at (loc, "variable or field declared void");
10852 type = error_mark_node;
10853 }
10854
10855 return type;
10856 }
10857
10858 /* Handle declaring DECL as an inline variable. */
10859
10860 static void
mark_inline_variable(tree decl,location_t loc)10861 mark_inline_variable (tree decl, location_t loc)
10862 {
10863 bool inlinep = true;
10864 if (! toplevel_bindings_p ())
10865 {
10866 error_at (loc, "%<inline%> specifier invalid for variable "
10867 "%qD declared at block scope", decl);
10868 inlinep = false;
10869 }
10870 else if (cxx_dialect < cxx17)
10871 pedwarn (loc, 0, "inline variables are only available "
10872 "with %<-std=c++17%> or %<-std=gnu++17%>");
10873 if (inlinep)
10874 {
10875 retrofit_lang_decl (decl);
10876 SET_DECL_VAR_DECLARED_INLINE_P (decl);
10877 }
10878 }
10879
10880
10881 /* Assign a typedef-given name to a class or enumeration type declared
10882 as anonymous at first. This was split out of grokdeclarator
10883 because it is also used in libcc1. */
10884
10885 void
name_unnamed_type(tree type,tree decl)10886 name_unnamed_type (tree type, tree decl)
10887 {
10888 gcc_assert (TYPE_UNNAMED_P (type));
10889
10890 /* Replace the anonymous name with the real name everywhere. */
10891 for (tree t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
10892 if (IDENTIFIER_ANON_P (TYPE_IDENTIFIER (t)))
10893 /* We do not rename the debug info representing the unnamed
10894 tagged type because the standard says in [dcl.typedef] that
10895 the naming applies only for linkage purposes. */
10896 /*debug_hooks->set_name (t, decl);*/
10897 TYPE_NAME (t) = decl;
10898
10899 /* If this is a typedef within a template class, the nested
10900 type is a (non-primary) template. The name for the
10901 template needs updating as well. */
10902 if (TYPE_LANG_SPECIFIC (type) && CLASSTYPE_TEMPLATE_INFO (type))
10903 DECL_NAME (CLASSTYPE_TI_TEMPLATE (type))
10904 = TYPE_IDENTIFIER (type);
10905
10906 /* Adjust linkage now that we aren't unnamed anymore. */
10907 reset_type_linkage (type);
10908
10909 /* FIXME remangle member functions; member functions of a
10910 type with external linkage have external linkage. */
10911
10912 /* Check that our job is done, and that it would fail if we
10913 attempted to do it again. */
10914 gcc_assert (!TYPE_UNNAMED_P (type));
10915 }
10916
10917 /* Given declspecs and a declarator (abstract or otherwise), determine
10918 the name and type of the object declared and construct a DECL node
10919 for it.
10920
10921 DECLSPECS points to the representation of declaration-specifier
10922 sequence that precedes declarator.
10923
10924 DECL_CONTEXT says which syntactic context this declaration is in:
10925 NORMAL for most contexts. Make a VAR_DECL or FUNCTION_DECL or TYPE_DECL.
10926 FUNCDEF for a function definition. Like NORMAL but a few different
10927 error messages in each case. Return value may be zero meaning
10928 this definition is too screwy to try to parse.
10929 MEMFUNCDEF for a function definition. Like FUNCDEF but prepares to
10930 handle member functions (which have FIELD context).
10931 Return value may be zero meaning this definition is too screwy to
10932 try to parse.
10933 PARM for a parameter declaration (either within a function prototype
10934 or before a function body). Make a PARM_DECL, or return void_type_node.
10935 TPARM for a template parameter declaration.
10936 CATCHPARM for a parameter declaration before a catch clause.
10937 TYPENAME if for a typename (in a cast or sizeof).
10938 Don't make a DECL node; just return the ..._TYPE node.
10939 FIELD for a struct or union field; make a FIELD_DECL.
10940 BITFIELD for a field with specified width.
10941
10942 INITIALIZED is as for start_decl.
10943
10944 ATTRLIST is a pointer to the list of attributes, which may be NULL
10945 if there are none; *ATTRLIST may be modified if attributes from inside
10946 the declarator should be applied to the declaration.
10947
10948 When this function is called, scoping variables (such as
10949 CURRENT_CLASS_TYPE) should reflect the scope in which the
10950 declaration occurs, not the scope in which the new declaration will
10951 be placed. For example, on:
10952
10953 void S::f() { ... }
10954
10955 when grokdeclarator is called for `S::f', the CURRENT_CLASS_TYPE
10956 should not be `S'.
10957
10958 Returns a DECL (if a declarator is present), a TYPE (if there is no
10959 declarator, in cases like "struct S;"), or the ERROR_MARK_NODE if an
10960 error occurs. */
10961
10962 tree
grokdeclarator(const cp_declarator * declarator,cp_decl_specifier_seq * declspecs,enum decl_context decl_context,int initialized,tree * attrlist)10963 grokdeclarator (const cp_declarator *declarator,
10964 cp_decl_specifier_seq *declspecs,
10965 enum decl_context decl_context,
10966 int initialized,
10967 tree* attrlist)
10968 {
10969 tree type = NULL_TREE;
10970 int longlong = 0;
10971 int explicit_intN = 0;
10972 int int_n_alt = 0;
10973 int virtualp, explicitp, friendp, inlinep, staticp;
10974 int explicit_int = 0;
10975 int explicit_char = 0;
10976 int defaulted_int = 0;
10977
10978 tree typedef_decl = NULL_TREE;
10979 const char *name = NULL;
10980 tree typedef_type = NULL_TREE;
10981 /* True if this declarator is a function definition. */
10982 bool funcdef_flag = false;
10983 cp_declarator_kind innermost_code = cdk_error;
10984 int bitfield = 0;
10985 #if 0
10986 /* See the code below that used this. */
10987 tree decl_attr = NULL_TREE;
10988 #endif
10989
10990 /* Keep track of what sort of function is being processed
10991 so that we can warn about default return values, or explicit
10992 return values which do not match prescribed defaults. */
10993 special_function_kind sfk = sfk_none;
10994
10995 tree dname = NULL_TREE;
10996 tree ctor_return_type = NULL_TREE;
10997 enum overload_flags flags = NO_SPECIAL;
10998 /* cv-qualifiers that apply to the declarator, for a declaration of
10999 a member function. */
11000 cp_cv_quals memfn_quals = TYPE_UNQUALIFIED;
11001 /* virt-specifiers that apply to the declarator, for a declaration of
11002 a member function. */
11003 cp_virt_specifiers virt_specifiers = VIRT_SPEC_UNSPECIFIED;
11004 /* ref-qualifier that applies to the declarator, for a declaration of
11005 a member function. */
11006 cp_ref_qualifier rqual = REF_QUAL_NONE;
11007 /* cv-qualifiers that apply to the type specified by the DECLSPECS. */
11008 int type_quals = get_type_quals (declspecs);
11009 tree raises = NULL_TREE;
11010 int template_count = 0;
11011 tree returned_attrs = NULL_TREE;
11012 tree parms = NULL_TREE;
11013 const cp_declarator *id_declarator;
11014 /* The unqualified name of the declarator; either an
11015 IDENTIFIER_NODE, BIT_NOT_EXPR, or TEMPLATE_ID_EXPR. */
11016 tree unqualified_id;
11017 /* The class type, if any, in which this entity is located,
11018 or NULL_TREE if none. Note that this value may be different from
11019 the current class type; for example if an attempt is made to declare
11020 "A::f" inside "B", this value will be "A". */
11021 tree ctype = current_class_type;
11022 /* The NAMESPACE_DECL for the namespace in which this entity is
11023 located. If an unqualified name is used to declare the entity,
11024 this value will be NULL_TREE, even if the entity is located at
11025 namespace scope. */
11026 tree in_namespace = NULL_TREE;
11027 cp_storage_class storage_class;
11028 bool unsigned_p, signed_p, short_p, long_p, thread_p;
11029 bool type_was_error_mark_node = false;
11030 bool parameter_pack_p = declarator ? declarator->parameter_pack_p : false;
11031 bool template_type_arg = false;
11032 bool template_parm_flag = false;
11033 bool typedef_p = decl_spec_seq_has_spec_p (declspecs, ds_typedef);
11034 bool constexpr_p = decl_spec_seq_has_spec_p (declspecs, ds_constexpr);
11035 bool constinit_p = decl_spec_seq_has_spec_p (declspecs, ds_constinit);
11036 bool consteval_p = decl_spec_seq_has_spec_p (declspecs, ds_consteval);
11037 bool late_return_type_p = false;
11038 bool array_parameter_p = false;
11039 tree reqs = NULL_TREE;
11040
11041 signed_p = decl_spec_seq_has_spec_p (declspecs, ds_signed);
11042 unsigned_p = decl_spec_seq_has_spec_p (declspecs, ds_unsigned);
11043 short_p = decl_spec_seq_has_spec_p (declspecs, ds_short);
11044 long_p = decl_spec_seq_has_spec_p (declspecs, ds_long);
11045 longlong = decl_spec_seq_has_spec_p (declspecs, ds_long_long);
11046 explicit_intN = declspecs->explicit_intN_p;
11047 int_n_alt = declspecs->int_n_alt;
11048 thread_p = decl_spec_seq_has_spec_p (declspecs, ds_thread);
11049
11050 // Was concept_p specified? Note that ds_concept
11051 // implies ds_constexpr!
11052 bool concept_p = decl_spec_seq_has_spec_p (declspecs, ds_concept);
11053 if (concept_p)
11054 constexpr_p = true;
11055
11056 if (decl_context == FUNCDEF)
11057 funcdef_flag = true, decl_context = NORMAL;
11058 else if (decl_context == MEMFUNCDEF)
11059 funcdef_flag = true, decl_context = FIELD;
11060 else if (decl_context == BITFIELD)
11061 bitfield = 1, decl_context = FIELD;
11062 else if (decl_context == TEMPLATE_TYPE_ARG)
11063 template_type_arg = true, decl_context = TYPENAME;
11064 else if (decl_context == TPARM)
11065 template_parm_flag = true, decl_context = PARM;
11066
11067 if (initialized > 1)
11068 funcdef_flag = true;
11069
11070 location_t typespec_loc = smallest_type_location (type_quals,
11071 declspecs->locations);
11072 if (typespec_loc == UNKNOWN_LOCATION)
11073 typespec_loc = input_location;
11074
11075 location_t id_loc = declarator ? declarator->id_loc : input_location;
11076 if (id_loc == UNKNOWN_LOCATION)
11077 id_loc = input_location;
11078
11079 /* Look inside a declarator for the name being declared
11080 and get it as a string, for an error message. */
11081 for (id_declarator = declarator;
11082 id_declarator;
11083 id_declarator = id_declarator->declarator)
11084 {
11085 if (id_declarator->kind != cdk_id)
11086 innermost_code = id_declarator->kind;
11087
11088 switch (id_declarator->kind)
11089 {
11090 case cdk_function:
11091 if (id_declarator->declarator
11092 && id_declarator->declarator->kind == cdk_id)
11093 {
11094 sfk = id_declarator->declarator->u.id.sfk;
11095 if (sfk == sfk_destructor)
11096 flags = DTOR_FLAG;
11097 }
11098 break;
11099
11100 case cdk_id:
11101 {
11102 tree qualifying_scope = id_declarator->u.id.qualifying_scope;
11103 tree decl = id_declarator->u.id.unqualified_name;
11104 if (!decl)
11105 break;
11106 if (qualifying_scope)
11107 {
11108 if (check_for_bare_parameter_packs (qualifying_scope,
11109 id_declarator->id_loc))
11110 return error_mark_node;
11111 if (at_function_scope_p ())
11112 {
11113 /* [dcl.meaning]
11114
11115 A declarator-id shall not be qualified except
11116 for ...
11117
11118 None of the cases are permitted in block
11119 scope. */
11120 if (qualifying_scope == global_namespace)
11121 error ("invalid use of qualified-name %<::%D%>",
11122 decl);
11123 else if (TYPE_P (qualifying_scope))
11124 error ("invalid use of qualified-name %<%T::%D%>",
11125 qualifying_scope, decl);
11126 else
11127 error ("invalid use of qualified-name %<%D::%D%>",
11128 qualifying_scope, decl);
11129 return error_mark_node;
11130 }
11131 else if (TYPE_P (qualifying_scope))
11132 {
11133 ctype = qualifying_scope;
11134 if (!MAYBE_CLASS_TYPE_P (ctype))
11135 {
11136 error_at (id_declarator->id_loc,
11137 "%q#T is not a class or namespace", ctype);
11138 ctype = NULL_TREE;
11139 }
11140 else if (innermost_code != cdk_function
11141 && current_class_type
11142 && !uniquely_derived_from_p (ctype,
11143 current_class_type))
11144 {
11145 error_at (id_declarator->id_loc,
11146 "invalid use of qualified-name %<%T::%D%>",
11147 qualifying_scope, decl);
11148 return error_mark_node;
11149 }
11150 }
11151 else if (TREE_CODE (qualifying_scope) == NAMESPACE_DECL)
11152 in_namespace = qualifying_scope;
11153 }
11154 switch (TREE_CODE (decl))
11155 {
11156 case BIT_NOT_EXPR:
11157 {
11158 if (innermost_code != cdk_function)
11159 {
11160 error_at (EXPR_LOCATION (decl),
11161 "declaration of %qE as non-function", decl);
11162 return error_mark_node;
11163 }
11164 else if (!qualifying_scope
11165 && !(current_class_type && at_class_scope_p ()))
11166 {
11167 error_at (EXPR_LOCATION (decl),
11168 "declaration of %qE as non-member", decl);
11169 return error_mark_node;
11170 }
11171
11172 tree type = TREE_OPERAND (decl, 0);
11173 if (TYPE_P (type))
11174 type = constructor_name (type);
11175 name = identifier_to_locale (IDENTIFIER_POINTER (type));
11176 dname = decl;
11177 }
11178 break;
11179
11180 case TEMPLATE_ID_EXPR:
11181 {
11182 tree fns = TREE_OPERAND (decl, 0);
11183
11184 dname = fns;
11185 if (!identifier_p (dname))
11186 dname = OVL_NAME (dname);
11187 }
11188 /* Fall through. */
11189
11190 case IDENTIFIER_NODE:
11191 if (identifier_p (decl))
11192 dname = decl;
11193
11194 if (IDENTIFIER_KEYWORD_P (dname))
11195 {
11196 error ("declarator-id missing; using reserved word %qD",
11197 dname);
11198 name = identifier_to_locale (IDENTIFIER_POINTER (dname));
11199 }
11200 else if (!IDENTIFIER_CONV_OP_P (dname))
11201 name = identifier_to_locale (IDENTIFIER_POINTER (dname));
11202 else
11203 {
11204 gcc_assert (flags == NO_SPECIAL);
11205 flags = TYPENAME_FLAG;
11206 sfk = sfk_conversion;
11207 tree glob = get_global_binding (dname);
11208 if (glob && TREE_CODE (glob) == TYPE_DECL)
11209 name = identifier_to_locale (IDENTIFIER_POINTER (dname));
11210 else
11211 name = "<invalid operator>";
11212 }
11213 break;
11214
11215 default:
11216 gcc_unreachable ();
11217 }
11218 break;
11219 }
11220
11221 case cdk_array:
11222 case cdk_pointer:
11223 case cdk_reference:
11224 case cdk_ptrmem:
11225 break;
11226
11227 case cdk_decomp:
11228 name = "structured binding";
11229 break;
11230
11231 case cdk_error:
11232 return error_mark_node;
11233
11234 default:
11235 gcc_unreachable ();
11236 }
11237 if (id_declarator->kind == cdk_id)
11238 break;
11239 }
11240
11241 /* [dcl.fct.edf]
11242
11243 The declarator in a function-definition shall have the form
11244 D1 ( parameter-declaration-clause) ... */
11245 if (funcdef_flag && innermost_code != cdk_function)
11246 {
11247 error_at (id_loc, "function definition does not declare parameters");
11248 return error_mark_node;
11249 }
11250
11251 if (flags == TYPENAME_FLAG
11252 && innermost_code != cdk_function
11253 && ! (ctype && !declspecs->any_specifiers_p))
11254 {
11255 error_at (id_loc, "declaration of %qD as non-function", dname);
11256 return error_mark_node;
11257 }
11258
11259 if (dname && identifier_p (dname))
11260 {
11261 if (UDLIT_OPER_P (dname)
11262 && innermost_code != cdk_function)
11263 {
11264 error_at (id_loc, "declaration of %qD as non-function", dname);
11265 return error_mark_node;
11266 }
11267
11268 if (IDENTIFIER_ANY_OP_P (dname))
11269 {
11270 if (typedef_p)
11271 {
11272 error_at (id_loc, "declaration of %qD as %<typedef%>", dname);
11273 return error_mark_node;
11274 }
11275 else if (decl_context == PARM || decl_context == CATCHPARM)
11276 {
11277 error_at (id_loc, "declaration of %qD as parameter", dname);
11278 return error_mark_node;
11279 }
11280 }
11281 }
11282
11283 /* Anything declared one level down from the top level
11284 must be one of the parameters of a function
11285 (because the body is at least two levels down). */
11286
11287 /* This heuristic cannot be applied to C++ nodes! Fixed, however,
11288 by not allowing C++ class definitions to specify their parameters
11289 with xdecls (must be spec.d in the parmlist).
11290
11291 Since we now wait to push a class scope until we are sure that
11292 we are in a legitimate method context, we must set oldcname
11293 explicitly (since current_class_name is not yet alive).
11294
11295 We also want to avoid calling this a PARM if it is in a namespace. */
11296
11297 if (decl_context == NORMAL && !toplevel_bindings_p ())
11298 {
11299 cp_binding_level *b = current_binding_level;
11300 current_binding_level = b->level_chain;
11301 if (current_binding_level != 0 && toplevel_bindings_p ())
11302 decl_context = PARM;
11303 current_binding_level = b;
11304 }
11305
11306 if (name == NULL)
11307 name = decl_context == PARM ? "parameter" : "type name";
11308
11309 if (consteval_p && constexpr_p)
11310 {
11311 error_at (declspecs->locations[ds_consteval],
11312 "both %qs and %qs specified", "constexpr", "consteval");
11313 return error_mark_node;
11314 }
11315
11316 if (concept_p && typedef_p)
11317 {
11318 error_at (declspecs->locations[ds_concept],
11319 "%qs cannot appear in a typedef declaration", "concept");
11320 return error_mark_node;
11321 }
11322
11323 if (constexpr_p && typedef_p)
11324 {
11325 error_at (declspecs->locations[ds_constexpr],
11326 "%qs cannot appear in a typedef declaration", "constexpr");
11327 return error_mark_node;
11328 }
11329
11330 if (consteval_p && typedef_p)
11331 {
11332 error_at (declspecs->locations[ds_consteval],
11333 "%qs cannot appear in a typedef declaration", "consteval");
11334 return error_mark_node;
11335 }
11336
11337 if (constinit_p && typedef_p)
11338 {
11339 error_at (declspecs->locations[ds_constinit],
11340 "%qs cannot appear in a typedef declaration", "constinit");
11341 return error_mark_node;
11342 }
11343
11344 /* [dcl.spec]/2 "At most one of the constexpr, consteval, and constinit
11345 keywords shall appear in a decl-specifier-seq." */
11346 if (constinit_p && constexpr_p)
11347 {
11348 gcc_rich_location richloc (declspecs->locations[ds_constinit]);
11349 richloc.add_range (declspecs->locations[ds_constexpr]);
11350 error_at (&richloc,
11351 "can use at most one of the %<constinit%> and %<constexpr%> "
11352 "specifiers");
11353 return error_mark_node;
11354 }
11355
11356 /* If there were multiple types specified in the decl-specifier-seq,
11357 issue an error message. */
11358 if (declspecs->multiple_types_p)
11359 {
11360 error_at (typespec_loc,
11361 "two or more data types in declaration of %qs", name);
11362 return error_mark_node;
11363 }
11364
11365 if (declspecs->conflicting_specifiers_p)
11366 {
11367 error_at (min_location (declspecs->locations[ds_typedef],
11368 declspecs->locations[ds_storage_class]),
11369 "conflicting specifiers in declaration of %qs", name);
11370 return error_mark_node;
11371 }
11372
11373 /* Extract the basic type from the decl-specifier-seq. */
11374 type = declspecs->type;
11375 if (type == error_mark_node)
11376 {
11377 type = NULL_TREE;
11378 type_was_error_mark_node = true;
11379 }
11380 cp_warn_deprecated_use (type);
11381 if (type && TREE_CODE (type) == TYPE_DECL)
11382 {
11383 cp_warn_deprecated_use_scopes (CP_DECL_CONTEXT (type));
11384 typedef_decl = type;
11385 type = TREE_TYPE (typedef_decl);
11386 if (DECL_ARTIFICIAL (typedef_decl))
11387 cp_warn_deprecated_use (type);
11388 }
11389 /* No type at all: default to `int', and set DEFAULTED_INT
11390 because it was not a user-defined typedef. */
11391 if (type == NULL_TREE)
11392 {
11393 if (signed_p || unsigned_p || long_p || short_p)
11394 {
11395 /* These imply 'int'. */
11396 type = integer_type_node;
11397 defaulted_int = 1;
11398 }
11399 /* If we just have "complex", it is equivalent to "complex double". */
11400 else if (!longlong && !explicit_intN
11401 && decl_spec_seq_has_spec_p (declspecs, ds_complex))
11402 {
11403 type = double_type_node;
11404 pedwarn (declspecs->locations[ds_complex], OPT_Wpedantic,
11405 "ISO C++ does not support plain %<complex%> meaning "
11406 "%<double complex%>");
11407 }
11408 }
11409 /* Gather flags. */
11410 explicit_int = declspecs->explicit_int_p;
11411 explicit_char = declspecs->explicit_char_p;
11412
11413 #if 0
11414 /* See the code below that used this. */
11415 if (typedef_decl)
11416 decl_attr = DECL_ATTRIBUTES (typedef_decl);
11417 #endif
11418 typedef_type = type;
11419
11420 if (sfk == sfk_conversion || sfk == sfk_deduction_guide)
11421 ctor_return_type = TREE_TYPE (dname);
11422 else
11423 ctor_return_type = ctype;
11424
11425 if (sfk != sfk_none)
11426 {
11427 type = check_special_function_return_type (sfk, type,
11428 ctor_return_type,
11429 type_quals,
11430 declspecs->locations);
11431 type_quals = TYPE_UNQUALIFIED;
11432 }
11433 else if (type == NULL_TREE)
11434 {
11435 int is_main;
11436
11437 explicit_int = -1;
11438
11439 /* We handle `main' specially here, because 'main () { }' is so
11440 common. With no options, it is allowed. With -Wreturn-type,
11441 it is a warning. It is only an error with -pedantic-errors. */
11442 is_main = (funcdef_flag
11443 && dname && identifier_p (dname)
11444 && MAIN_NAME_P (dname)
11445 && ctype == NULL_TREE
11446 && in_namespace == NULL_TREE
11447 && current_namespace == global_namespace);
11448
11449 if (type_was_error_mark_node)
11450 /* We've already issued an error, don't complain more. */;
11451 else if (in_system_header_at (id_loc) || flag_ms_extensions)
11452 /* Allow it, sigh. */;
11453 else if (! is_main)
11454 permerror (id_loc, "ISO C++ forbids declaration of %qs with no type",
11455 name);
11456 else if (pedantic)
11457 pedwarn (id_loc, OPT_Wpedantic,
11458 "ISO C++ forbids declaration of %qs with no type", name);
11459 else
11460 warning_at (id_loc, OPT_Wreturn_type,
11461 "ISO C++ forbids declaration of %qs with no type", name);
11462
11463 if (type_was_error_mark_node && template_parm_flag)
11464 /* FIXME we should be able to propagate the error_mark_node as is
11465 for other contexts too. */
11466 type = error_mark_node;
11467 else
11468 type = integer_type_node;
11469 }
11470
11471 ctype = NULL_TREE;
11472
11473 if (explicit_intN)
11474 {
11475 if (! int_n_enabled_p[declspecs->int_n_idx])
11476 {
11477 error_at (declspecs->locations[ds_type_spec],
11478 "%<__int%d%> is not supported by this target",
11479 int_n_data[declspecs->int_n_idx].bitsize);
11480 explicit_intN = false;
11481 }
11482 /* Don't pedwarn if the alternate "__intN__" form has been used instead
11483 of "__intN". */
11484 else if (!int_n_alt && pedantic)
11485 pedwarn (declspecs->locations[ds_type_spec], OPT_Wpedantic,
11486 "ISO C++ does not support %<__int%d%> for %qs",
11487 int_n_data[declspecs->int_n_idx].bitsize, name);
11488 }
11489
11490 /* Now process the modifiers that were specified
11491 and check for invalid combinations. */
11492
11493 /* Long double is a special combination. */
11494 if (long_p && !longlong && TYPE_MAIN_VARIANT (type) == double_type_node)
11495 {
11496 long_p = false;
11497 type = cp_build_qualified_type (long_double_type_node,
11498 cp_type_quals (type));
11499 }
11500
11501 /* Check all other uses of type modifiers. */
11502
11503 if (unsigned_p || signed_p || long_p || short_p)
11504 {
11505 location_t loc;
11506 const char *key;
11507 if (unsigned_p)
11508 {
11509 key = "unsigned";
11510 loc = declspecs->locations[ds_unsigned];
11511 }
11512 else if (signed_p)
11513 {
11514 key = "signed";
11515 loc = declspecs->locations[ds_signed];
11516 }
11517 else if (longlong)
11518 {
11519 key = "long long";
11520 loc = declspecs->locations[ds_long_long];
11521 }
11522 else if (long_p)
11523 {
11524 key = "long";
11525 loc = declspecs->locations[ds_long];
11526 }
11527 else /* if (short_p) */
11528 {
11529 key = "short";
11530 loc = declspecs->locations[ds_short];
11531 }
11532
11533 int ok = 0;
11534
11535 if (signed_p && unsigned_p)
11536 {
11537 gcc_rich_location richloc (declspecs->locations[ds_signed]);
11538 richloc.add_range (declspecs->locations[ds_unsigned]);
11539 error_at (&richloc,
11540 "%<signed%> and %<unsigned%> specified together");
11541 }
11542 else if (long_p && short_p)
11543 {
11544 gcc_rich_location richloc (declspecs->locations[ds_long]);
11545 richloc.add_range (declspecs->locations[ds_short]);
11546 error_at (&richloc, "%<long%> and %<short%> specified together");
11547 }
11548 else if (TREE_CODE (type) != INTEGER_TYPE
11549 || type == char8_type_node
11550 || type == char16_type_node
11551 || type == char32_type_node
11552 || ((long_p || short_p)
11553 && (explicit_char || explicit_intN)))
11554 error_at (loc, "%qs specified with %qT", key, type);
11555 else if (!explicit_int && !defaulted_int
11556 && !explicit_char && !explicit_intN)
11557 {
11558 if (typedef_decl)
11559 {
11560 pedwarn (loc, OPT_Wpedantic, "%qs specified with %qT",
11561 key, type);
11562 ok = !flag_pedantic_errors;
11563 }
11564 else if (declspecs->decltype_p)
11565 error_at (loc, "%qs specified with %<decltype%>", key);
11566 else
11567 error_at (loc, "%qs specified with %<typeof%>", key);
11568 }
11569 else
11570 ok = 1;
11571
11572 /* Discard the type modifiers if they are invalid. */
11573 if (! ok)
11574 {
11575 unsigned_p = false;
11576 signed_p = false;
11577 long_p = false;
11578 short_p = false;
11579 longlong = 0;
11580 }
11581 }
11582
11583 /* Decide whether an integer type is signed or not.
11584 Optionally treat bitfields as signed by default. */
11585 if (unsigned_p
11586 /* [class.bit]
11587
11588 It is implementation-defined whether a plain (neither
11589 explicitly signed or unsigned) char, short, int, or long
11590 bit-field is signed or unsigned.
11591
11592 Naturally, we extend this to long long as well. Note that
11593 this does not include wchar_t. */
11594 || (bitfield && !flag_signed_bitfields
11595 && !signed_p
11596 /* A typedef for plain `int' without `signed' can be
11597 controlled just like plain `int', but a typedef for
11598 `signed int' cannot be so controlled. */
11599 && !(typedef_decl
11600 && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl))
11601 && TREE_CODE (type) == INTEGER_TYPE
11602 && !same_type_p (TYPE_MAIN_VARIANT (type), wchar_type_node)))
11603 {
11604 if (explicit_intN)
11605 type = int_n_trees[declspecs->int_n_idx].unsigned_type;
11606 else if (longlong)
11607 type = long_long_unsigned_type_node;
11608 else if (long_p)
11609 type = long_unsigned_type_node;
11610 else if (short_p)
11611 type = short_unsigned_type_node;
11612 else if (type == char_type_node)
11613 type = unsigned_char_type_node;
11614 else if (typedef_decl)
11615 type = unsigned_type_for (type);
11616 else
11617 type = unsigned_type_node;
11618 }
11619 else if (signed_p && type == char_type_node)
11620 type = signed_char_type_node;
11621 else if (explicit_intN)
11622 type = int_n_trees[declspecs->int_n_idx].signed_type;
11623 else if (longlong)
11624 type = long_long_integer_type_node;
11625 else if (long_p)
11626 type = long_integer_type_node;
11627 else if (short_p)
11628 type = short_integer_type_node;
11629
11630 if (decl_spec_seq_has_spec_p (declspecs, ds_complex))
11631 {
11632 if (TREE_CODE (type) != INTEGER_TYPE && TREE_CODE (type) != REAL_TYPE)
11633 error_at (declspecs->locations[ds_complex],
11634 "complex invalid for %qs", name);
11635 /* If a modifier is specified, the resulting complex is the complex
11636 form of TYPE. E.g, "complex short" is "complex short int". */
11637 else if (type == integer_type_node)
11638 type = complex_integer_type_node;
11639 else if (type == float_type_node)
11640 type = complex_float_type_node;
11641 else if (type == double_type_node)
11642 type = complex_double_type_node;
11643 else if (type == long_double_type_node)
11644 type = complex_long_double_type_node;
11645 else
11646 type = build_complex_type (type);
11647 }
11648
11649 /* If we're using the injected-class-name to form a compound type or a
11650 declaration, replace it with the underlying class so we don't get
11651 redundant typedefs in the debug output. But if we are returning the
11652 type unchanged, leave it alone so that it's available to
11653 maybe_get_template_decl_from_type_decl. */
11654 if (CLASS_TYPE_P (type)
11655 && DECL_SELF_REFERENCE_P (TYPE_NAME (type))
11656 && type == TREE_TYPE (TYPE_NAME (type))
11657 && (declarator || type_quals))
11658 type = DECL_ORIGINAL_TYPE (TYPE_NAME (type));
11659
11660 type_quals |= cp_type_quals (type);
11661 type = cp_build_qualified_type_real
11662 (type, type_quals, ((((typedef_decl && !DECL_ARTIFICIAL (typedef_decl))
11663 || declspecs->decltype_p)
11664 ? tf_ignore_bad_quals : 0) | tf_warning_or_error));
11665 /* We might have ignored or rejected some of the qualifiers. */
11666 type_quals = cp_type_quals (type);
11667
11668 if (cxx_dialect >= cxx17 && type && is_auto (type)
11669 && innermost_code != cdk_function
11670 && id_declarator && declarator != id_declarator)
11671 if (tree tmpl = CLASS_PLACEHOLDER_TEMPLATE (type))
11672 {
11673 error_at (typespec_loc, "template placeholder type %qT must be followed "
11674 "by a simple declarator-id", type);
11675 inform (DECL_SOURCE_LOCATION (tmpl), "%qD declared here", tmpl);
11676 type = error_mark_node;
11677 }
11678
11679 staticp = 0;
11680 inlinep = decl_spec_seq_has_spec_p (declspecs, ds_inline);
11681 virtualp = decl_spec_seq_has_spec_p (declspecs, ds_virtual);
11682 explicitp = decl_spec_seq_has_spec_p (declspecs, ds_explicit);
11683
11684 storage_class = declspecs->storage_class;
11685 if (storage_class == sc_static)
11686 staticp = 1 + (decl_context == FIELD);
11687
11688 if (virtualp)
11689 {
11690 if (staticp == 2)
11691 {
11692 gcc_rich_location richloc (declspecs->locations[ds_virtual]);
11693 richloc.add_range (declspecs->locations[ds_storage_class]);
11694 error_at (&richloc, "member %qD cannot be declared both %<virtual%> "
11695 "and %<static%>", dname);
11696 storage_class = sc_none;
11697 staticp = 0;
11698 }
11699 if (constexpr_p && cxx_dialect < cxx2a)
11700 {
11701 gcc_rich_location richloc (declspecs->locations[ds_virtual]);
11702 richloc.add_range (declspecs->locations[ds_constexpr]);
11703 pedwarn (&richloc, OPT_Wpedantic, "member %qD can be declared both "
11704 "%<virtual%> and %<constexpr%> only in %<-std=c++2a%> or "
11705 "%<-std=gnu++2a%>", dname);
11706 }
11707 }
11708 friendp = decl_spec_seq_has_spec_p (declspecs, ds_friend);
11709
11710 /* Issue errors about use of storage classes for parameters. */
11711 if (decl_context == PARM)
11712 {
11713 if (typedef_p)
11714 {
11715 error_at (declspecs->locations[ds_typedef],
11716 "typedef declaration invalid in parameter declaration");
11717 return error_mark_node;
11718 }
11719 else if (template_parm_flag && storage_class != sc_none)
11720 {
11721 error_at (min_location (declspecs->locations[ds_thread],
11722 declspecs->locations[ds_storage_class]),
11723 "storage class specified for template parameter %qs",
11724 name);
11725 return error_mark_node;
11726 }
11727 else if (storage_class == sc_static
11728 || storage_class == sc_extern
11729 || thread_p)
11730 {
11731 error_at (min_location (declspecs->locations[ds_thread],
11732 declspecs->locations[ds_storage_class]),
11733 "storage class specified for parameter %qs", name);
11734 return error_mark_node;
11735 }
11736
11737 /* Function parameters cannot be concept. */
11738 if (concept_p)
11739 {
11740 error_at (declspecs->locations[ds_concept],
11741 "a parameter cannot be declared %qs", "concept");
11742 concept_p = 0;
11743 constexpr_p = 0;
11744 }
11745 /* Function parameters cannot be constexpr. If we saw one, moan
11746 and pretend it wasn't there. */
11747 else if (constexpr_p)
11748 {
11749 error_at (declspecs->locations[ds_constexpr],
11750 "a parameter cannot be declared %qs", "constexpr");
11751 constexpr_p = 0;
11752 }
11753 if (constinit_p)
11754 {
11755 error_at (declspecs->locations[ds_constinit],
11756 "a parameter cannot be declared %qs", "constinit");
11757 constinit_p = 0;
11758 }
11759 if (consteval_p)
11760 {
11761 error_at (declspecs->locations[ds_consteval],
11762 "a parameter cannot be declared %qs", "consteval");
11763 consteval_p = 0;
11764 }
11765 }
11766
11767 /* Give error if `virtual' is used outside of class declaration. */
11768 if (virtualp
11769 && (current_class_name == NULL_TREE || decl_context != FIELD))
11770 {
11771 error_at (declspecs->locations[ds_virtual],
11772 "%<virtual%> outside class declaration");
11773 virtualp = 0;
11774 }
11775
11776 if (innermost_code == cdk_decomp)
11777 {
11778 location_t loc = (declarator->kind == cdk_reference
11779 ? declarator->declarator->id_loc : declarator->id_loc);
11780 if (inlinep)
11781 error_at (declspecs->locations[ds_inline],
11782 "structured binding declaration cannot be %qs", "inline");
11783 if (typedef_p)
11784 error_at (declspecs->locations[ds_typedef],
11785 "structured binding declaration cannot be %qs", "typedef");
11786 if (constexpr_p && !concept_p)
11787 error_at (declspecs->locations[ds_constexpr], "structured "
11788 "binding declaration cannot be %qs", "constexpr");
11789 if (consteval_p)
11790 error_at (declspecs->locations[ds_consteval], "structured "
11791 "binding declaration cannot be %qs", "consteval");
11792 if (thread_p && cxx_dialect < cxx2a)
11793 pedwarn (declspecs->locations[ds_thread], 0,
11794 "structured binding declaration can be %qs only in "
11795 "%<-std=c++2a%> or %<-std=gnu++2a%>",
11796 declspecs->gnu_thread_keyword_p
11797 ? "__thread" : "thread_local");
11798 if (concept_p)
11799 error_at (declspecs->locations[ds_concept],
11800 "structured binding declaration cannot be %qs", "concept");
11801 /* [dcl.struct.bind] "A cv that includes volatile is deprecated." */
11802 if (type_quals & TYPE_QUAL_VOLATILE)
11803 warning_at (declspecs->locations[ds_volatile], OPT_Wvolatile,
11804 "%<volatile%>-qualified structured binding is deprecated");
11805 switch (storage_class)
11806 {
11807 case sc_none:
11808 break;
11809 case sc_register:
11810 error_at (loc, "structured binding declaration cannot be %qs",
11811 "register");
11812 break;
11813 case sc_static:
11814 if (cxx_dialect < cxx2a)
11815 pedwarn (loc, 0,
11816 "structured binding declaration can be %qs only in "
11817 "%<-std=c++2a%> or %<-std=gnu++2a%>", "static");
11818 break;
11819 case sc_extern:
11820 error_at (loc, "structured binding declaration cannot be %qs",
11821 "extern");
11822 break;
11823 case sc_mutable:
11824 error_at (loc, "structured binding declaration cannot be %qs",
11825 "mutable");
11826 break;
11827 case sc_auto:
11828 error_at (loc, "structured binding declaration cannot be "
11829 "C++98 %<auto%>");
11830 break;
11831 default:
11832 gcc_unreachable ();
11833 }
11834 if (TREE_CODE (type) != TEMPLATE_TYPE_PARM
11835 || TYPE_IDENTIFIER (type) != auto_identifier)
11836 {
11837 if (type != error_mark_node)
11838 {
11839 error_at (loc, "structured binding declaration cannot have "
11840 "type %qT", type);
11841 inform (loc,
11842 "type must be cv-qualified %<auto%> or reference to "
11843 "cv-qualified %<auto%>");
11844 }
11845 type = build_qualified_type (make_auto (), type_quals);
11846 declspecs->type = type;
11847 }
11848 inlinep = 0;
11849 typedef_p = 0;
11850 constexpr_p = 0;
11851 consteval_p = 0;
11852 concept_p = 0;
11853 if (storage_class != sc_static)
11854 {
11855 storage_class = sc_none;
11856 declspecs->storage_class = sc_none;
11857 }
11858 }
11859
11860 /* Static anonymous unions are dealt with here. */
11861 if (staticp && decl_context == TYPENAME
11862 && declspecs->type
11863 && ANON_AGGR_TYPE_P (declspecs->type))
11864 decl_context = FIELD;
11865
11866 /* Warn about storage classes that are invalid for certain
11867 kinds of declarations (parameters, typenames, etc.). */
11868 if (thread_p
11869 && ((storage_class
11870 && storage_class != sc_extern
11871 && storage_class != sc_static)
11872 || typedef_p))
11873 {
11874 location_t loc
11875 = min_location (declspecs->locations[ds_thread],
11876 declspecs->locations[ds_storage_class]);
11877 error_at (loc, "multiple storage classes in declaration of %qs", name);
11878 thread_p = false;
11879 }
11880 if (decl_context != NORMAL
11881 && ((storage_class != sc_none
11882 && storage_class != sc_mutable)
11883 || thread_p))
11884 {
11885 if ((decl_context == PARM || decl_context == CATCHPARM)
11886 && (storage_class == sc_register
11887 || storage_class == sc_auto))
11888 ;
11889 else if (typedef_p)
11890 ;
11891 else if (decl_context == FIELD
11892 /* C++ allows static class elements. */
11893 && storage_class == sc_static)
11894 /* C++ also allows inlines and signed and unsigned elements,
11895 but in those cases we don't come in here. */
11896 ;
11897 else
11898 {
11899 location_t loc
11900 = min_location (declspecs->locations[ds_thread],
11901 declspecs->locations[ds_storage_class]);
11902 if (decl_context == FIELD)
11903 error_at (loc, "storage class specified for %qs", name);
11904 else if (decl_context == PARM || decl_context == CATCHPARM)
11905 error_at (loc, "storage class specified for parameter %qs", name);
11906 else
11907 error_at (loc, "storage class specified for typename");
11908 if (storage_class == sc_register
11909 || storage_class == sc_auto
11910 || storage_class == sc_extern
11911 || thread_p)
11912 storage_class = sc_none;
11913 }
11914 }
11915 else if (storage_class == sc_extern && funcdef_flag
11916 && ! toplevel_bindings_p ())
11917 error ("nested function %qs declared %<extern%>", name);
11918 else if (toplevel_bindings_p ())
11919 {
11920 if (storage_class == sc_auto)
11921 error_at (declspecs->locations[ds_storage_class],
11922 "top-level declaration of %qs specifies %<auto%>", name);
11923 }
11924 else if (thread_p
11925 && storage_class != sc_extern
11926 && storage_class != sc_static)
11927 {
11928 if (declspecs->gnu_thread_keyword_p)
11929 pedwarn (declspecs->locations[ds_thread],
11930 0, "function-scope %qs implicitly auto and "
11931 "declared %<__thread%>", name);
11932
11933 /* When thread_local is applied to a variable of block scope the
11934 storage-class-specifier static is implied if it does not appear
11935 explicitly. */
11936 storage_class = declspecs->storage_class = sc_static;
11937 staticp = 1;
11938 }
11939
11940 if (storage_class && friendp)
11941 {
11942 error_at (min_location (declspecs->locations[ds_thread],
11943 declspecs->locations[ds_storage_class]),
11944 "storage class specifiers invalid in friend function "
11945 "declarations");
11946 storage_class = sc_none;
11947 staticp = 0;
11948 }
11949
11950 if (!id_declarator)
11951 unqualified_id = NULL_TREE;
11952 else
11953 {
11954 unqualified_id = id_declarator->u.id.unqualified_name;
11955 switch (TREE_CODE (unqualified_id))
11956 {
11957 case BIT_NOT_EXPR:
11958 unqualified_id = TREE_OPERAND (unqualified_id, 0);
11959 if (TYPE_P (unqualified_id))
11960 unqualified_id = constructor_name (unqualified_id);
11961 break;
11962
11963 case IDENTIFIER_NODE:
11964 case TEMPLATE_ID_EXPR:
11965 break;
11966
11967 default:
11968 gcc_unreachable ();
11969 }
11970 }
11971
11972 if (declspecs->std_attributes)
11973 {
11974 location_t attr_loc = declspecs->locations[ds_std_attribute];
11975 if (warning_at (attr_loc, OPT_Wattributes, "attribute ignored"))
11976 inform (attr_loc, "an attribute that appertains to a type-specifier "
11977 "is ignored");
11978 }
11979
11980 /* Determine the type of the entity declared by recurring on the
11981 declarator. */
11982 for (; declarator; declarator = declarator->declarator)
11983 {
11984 const cp_declarator *inner_declarator;
11985 tree attrs;
11986
11987 if (type == error_mark_node)
11988 return error_mark_node;
11989
11990 attrs = declarator->attributes;
11991 if (attrs)
11992 {
11993 int attr_flags;
11994
11995 attr_flags = 0;
11996 if (declarator == NULL || declarator->kind == cdk_id)
11997 attr_flags |= (int) ATTR_FLAG_DECL_NEXT;
11998 if (declarator->kind == cdk_function)
11999 attr_flags |= (int) ATTR_FLAG_FUNCTION_NEXT;
12000 if (declarator->kind == cdk_array)
12001 attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT;
12002 tree late_attrs = NULL_TREE;
12003 if (decl_context != PARM && decl_context != TYPENAME)
12004 /* Assume that any attributes that get applied late to
12005 templates will DTRT when applied to the declaration
12006 as a whole. */
12007 late_attrs = splice_template_attributes (&attrs, type);
12008 returned_attrs = decl_attributes (&type,
12009 chainon (returned_attrs, attrs),
12010 attr_flags);
12011 returned_attrs = chainon (late_attrs, returned_attrs);
12012 }
12013
12014 inner_declarator = declarator->declarator;
12015
12016 /* We don't want to warn in parameter context because we don't
12017 yet know if the parse will succeed, and this might turn out
12018 to be a constructor call. */
12019 if (decl_context != PARM
12020 && decl_context != TYPENAME
12021 && !typedef_p
12022 && declarator->parenthesized != UNKNOWN_LOCATION
12023 /* If the type is class-like and the inner name used a
12024 global namespace qualifier, we need the parens.
12025 Unfortunately all we can tell is whether a qualified name
12026 was used or not. */
12027 && !(inner_declarator
12028 && inner_declarator->kind == cdk_id
12029 && inner_declarator->u.id.qualifying_scope
12030 && (MAYBE_CLASS_TYPE_P (type)
12031 || TREE_CODE (type) == ENUMERAL_TYPE)))
12032 warning_at (declarator->parenthesized, OPT_Wparentheses,
12033 "unnecessary parentheses in declaration of %qs", name);
12034 if (declarator->kind == cdk_id || declarator->kind == cdk_decomp)
12035 break;
12036
12037 switch (declarator->kind)
12038 {
12039 case cdk_array:
12040 type = create_array_type_for_decl (dname, type,
12041 declarator->u.array.bounds,
12042 declarator->id_loc);
12043 if (!valid_array_size_p (dname
12044 ? declarator->id_loc : input_location,
12045 type, dname))
12046 type = error_mark_node;
12047
12048 if (declarator->std_attributes)
12049 /* [dcl.array]/1:
12050
12051 The optional attribute-specifier-seq appertains to the
12052 array. */
12053 returned_attrs = chainon (returned_attrs,
12054 declarator->std_attributes);
12055 break;
12056
12057 case cdk_function:
12058 {
12059 tree arg_types;
12060 int funcdecl_p;
12061
12062 /* Declaring a function type. */
12063
12064 {
12065 iloc_sentinel ils (declspecs->locations[ds_type_spec]);
12066 abstract_virtuals_error (ACU_RETURN, type);
12067 }
12068
12069 /* Pick up type qualifiers which should be applied to `this'. */
12070 memfn_quals = declarator->u.function.qualifiers;
12071 /* Pick up virt-specifiers. */
12072 virt_specifiers = declarator->u.function.virt_specifiers;
12073 /* And ref-qualifier, too */
12074 rqual = declarator->u.function.ref_qualifier;
12075 /* And tx-qualifier. */
12076 tree tx_qual = declarator->u.function.tx_qualifier;
12077 /* Pick up the exception specifications. */
12078 raises = declarator->u.function.exception_specification;
12079 /* If the exception-specification is ill-formed, let's pretend
12080 there wasn't one. */
12081 if (raises == error_mark_node)
12082 raises = NULL_TREE;
12083
12084 if (reqs)
12085 error_at (location_of (reqs), "requires-clause on return type");
12086 reqs = declarator->u.function.requires_clause;
12087
12088 /* Say it's a definition only for the CALL_EXPR
12089 closest to the identifier. */
12090 funcdecl_p = inner_declarator && inner_declarator->kind == cdk_id;
12091
12092 /* Handle a late-specified return type. */
12093 tree late_return_type = declarator->u.function.late_return_type;
12094 if (funcdecl_p
12095 /* This is the case e.g. for
12096 using T = auto () -> int. */
12097 || inner_declarator == NULL)
12098 {
12099 if (tree auto_node = type_uses_auto (type))
12100 {
12101 if (!late_return_type)
12102 {
12103 if (current_class_type
12104 && LAMBDA_TYPE_P (current_class_type))
12105 /* OK for C++11 lambdas. */;
12106 else if (cxx_dialect < cxx14)
12107 {
12108 error_at (typespec_loc, "%qs function uses "
12109 "%<auto%> type specifier without "
12110 "trailing return type", name);
12111 inform (typespec_loc,
12112 "deduced return type only available "
12113 "with %<-std=c++14%> or %<-std=gnu++14%>");
12114 }
12115 else if (virtualp)
12116 {
12117 error_at (typespec_loc, "virtual function "
12118 "cannot have deduced return type");
12119 virtualp = false;
12120 }
12121 }
12122 else if (!is_auto (type) && sfk != sfk_conversion)
12123 {
12124 error_at (typespec_loc, "%qs function with trailing "
12125 "return type has %qT as its type rather "
12126 "than plain %<auto%>", name, type);
12127 return error_mark_node;
12128 }
12129 else if (is_auto (type) && AUTO_IS_DECLTYPE (type))
12130 {
12131 if (funcdecl_p)
12132 error_at (typespec_loc,
12133 "%qs function with trailing return type "
12134 "has %<decltype(auto)%> as its type "
12135 "rather than plain %<auto%>", name);
12136 else
12137 error_at (typespec_loc,
12138 "invalid use of %<decltype(auto)%>");
12139 return error_mark_node;
12140 }
12141 tree tmpl = CLASS_PLACEHOLDER_TEMPLATE (auto_node);
12142 if (!tmpl)
12143 if (tree late_auto = type_uses_auto (late_return_type))
12144 tmpl = CLASS_PLACEHOLDER_TEMPLATE (late_auto);
12145 if (tmpl && funcdecl_p)
12146 {
12147 if (!dguide_name_p (unqualified_id))
12148 {
12149 error_at (declarator->id_loc, "deduced class "
12150 "type %qD in function return type",
12151 DECL_NAME (tmpl));
12152 inform (DECL_SOURCE_LOCATION (tmpl),
12153 "%qD declared here", tmpl);
12154 return error_mark_node;
12155 }
12156 else if (!late_return_type)
12157 {
12158 error_at (declarator->id_loc, "deduction guide "
12159 "for %qT must have trailing return "
12160 "type", TREE_TYPE (tmpl));
12161 inform (DECL_SOURCE_LOCATION (tmpl),
12162 "%qD declared here", tmpl);
12163 return error_mark_node;
12164 }
12165 else if (CLASS_TYPE_P (late_return_type)
12166 && CLASSTYPE_TEMPLATE_INFO (late_return_type)
12167 && (CLASSTYPE_TI_TEMPLATE (late_return_type)
12168 == tmpl))
12169 /* OK */;
12170 else
12171 error ("trailing return type %qT of deduction guide "
12172 "is not a specialization of %qT",
12173 late_return_type, TREE_TYPE (tmpl));
12174 }
12175 }
12176 else if (late_return_type
12177 && sfk != sfk_conversion)
12178 {
12179 if (late_return_type == error_mark_node)
12180 return error_mark_node;
12181 if (cxx_dialect < cxx11)
12182 /* Not using maybe_warn_cpp0x because this should
12183 always be an error. */
12184 error_at (typespec_loc,
12185 "trailing return type only available "
12186 "with %<-std=c++11%> or %<-std=gnu++11%>");
12187 else
12188 error_at (typespec_loc, "%qs function with trailing "
12189 "return type not declared with %<auto%> "
12190 "type specifier", name);
12191 return error_mark_node;
12192 }
12193 }
12194 type = splice_late_return_type (type, late_return_type);
12195 if (type == error_mark_node)
12196 return error_mark_node;
12197
12198 if (late_return_type)
12199 {
12200 late_return_type_p = true;
12201 type_quals = cp_type_quals (type);
12202 }
12203
12204 if (type_quals != TYPE_UNQUALIFIED)
12205 {
12206 if (SCALAR_TYPE_P (type) || VOID_TYPE_P (type))
12207 warning_at (typespec_loc, OPT_Wignored_qualifiers, "type "
12208 "qualifiers ignored on function return type");
12209 /* [dcl.fct] "A volatile-qualified return type is
12210 deprecated." */
12211 if (type_quals & TYPE_QUAL_VOLATILE)
12212 warning_at (typespec_loc, OPT_Wvolatile,
12213 "%<volatile%>-qualified return type is "
12214 "deprecated");
12215
12216 /* We now know that the TYPE_QUALS don't apply to the
12217 decl, but to its return type. */
12218 type_quals = TYPE_UNQUALIFIED;
12219 }
12220
12221 /* Error about some types functions can't return. */
12222
12223 if (TREE_CODE (type) == FUNCTION_TYPE)
12224 {
12225 error_at (typespec_loc, "%qs declared as function returning "
12226 "a function", name);
12227 return error_mark_node;
12228 }
12229 if (TREE_CODE (type) == ARRAY_TYPE)
12230 {
12231 error_at (typespec_loc, "%qs declared as function returning "
12232 "an array", name);
12233 return error_mark_node;
12234 }
12235 if (constinit_p)
12236 {
12237 error_at (declspecs->locations[ds_constinit],
12238 "%<constinit%> on function return type is not "
12239 "allowed");
12240 return error_mark_node;
12241 }
12242 /* Only plain decltype(auto) is allowed. */
12243 if (tree a = type_uses_auto (type))
12244 {
12245 if (AUTO_IS_DECLTYPE (a) && a != type)
12246 {
12247 error_at (typespec_loc, "%qT as type rather than "
12248 "plain %<decltype(auto)%>", type);
12249 return error_mark_node;
12250 }
12251 }
12252
12253 if (ctype == NULL_TREE
12254 && decl_context == FIELD
12255 && funcdecl_p
12256 && friendp == 0)
12257 ctype = current_class_type;
12258
12259 if (ctype && (sfk == sfk_constructor
12260 || sfk == sfk_destructor))
12261 {
12262 /* We are within a class's scope. If our declarator name
12263 is the same as the class name, and we are defining
12264 a function, then it is a constructor/destructor, and
12265 therefore returns a void type. */
12266
12267 /* ISO C++ 12.4/2. A destructor may not be declared
12268 const or volatile. A destructor may not be static.
12269 A destructor may not be declared with ref-qualifier.
12270
12271 ISO C++ 12.1. A constructor may not be declared
12272 const or volatile. A constructor may not be
12273 virtual. A constructor may not be static.
12274 A constructor may not be declared with ref-qualifier. */
12275 if (staticp == 2)
12276 error_at (declspecs->locations[ds_storage_class],
12277 (flags == DTOR_FLAG)
12278 ? G_("destructor cannot be static member "
12279 "function")
12280 : G_("constructor cannot be static member "
12281 "function"));
12282 if (memfn_quals)
12283 {
12284 error ((flags == DTOR_FLAG)
12285 ? G_("destructors may not be cv-qualified")
12286 : G_("constructors may not be cv-qualified"));
12287 memfn_quals = TYPE_UNQUALIFIED;
12288 }
12289
12290 if (rqual)
12291 {
12292 maybe_warn_cpp0x (CPP0X_REF_QUALIFIER);
12293 error ((flags == DTOR_FLAG)
12294 ? G_("destructors may not be ref-qualified")
12295 : G_("constructors may not be ref-qualified"));
12296 rqual = REF_QUAL_NONE;
12297 }
12298
12299 if (decl_context == FIELD
12300 && !member_function_or_else (ctype,
12301 current_class_type,
12302 flags))
12303 return error_mark_node;
12304
12305 if (flags != DTOR_FLAG)
12306 {
12307 /* It's a constructor. */
12308 if (explicitp == 1)
12309 explicitp = 2;
12310 if (virtualp)
12311 {
12312 permerror (declspecs->locations[ds_virtual],
12313 "constructors cannot be declared %<virtual%>");
12314 virtualp = 0;
12315 }
12316 if (decl_context == FIELD
12317 && sfk != sfk_constructor)
12318 return error_mark_node;
12319 }
12320 if (decl_context == FIELD)
12321 staticp = 0;
12322 }
12323 else if (friendp)
12324 {
12325 if (virtualp)
12326 {
12327 /* Cannot be both friend and virtual. */
12328 gcc_rich_location richloc (declspecs->locations[ds_virtual]);
12329 richloc.add_range (declspecs->locations[ds_friend]);
12330 error_at (&richloc, "virtual functions cannot be friends");
12331 friendp = 0;
12332 }
12333 if (decl_context == NORMAL)
12334 error_at (declarator->id_loc,
12335 "friend declaration not in class definition");
12336 if (current_function_decl && funcdef_flag)
12337 {
12338 error_at (declarator->id_loc,
12339 "cannot define friend function %qs in a local "
12340 "class definition", name);
12341 friendp = 0;
12342 }
12343 /* [class.friend]/6: A function can be defined in a friend
12344 declaration if the function name is unqualified. */
12345 if (funcdef_flag && in_namespace)
12346 {
12347 if (in_namespace == global_namespace)
12348 error_at (declarator->id_loc,
12349 "friend function definition %qs cannot have "
12350 "a name qualified with %<::%>", name);
12351 else
12352 error_at (declarator->id_loc,
12353 "friend function definition %qs cannot have "
12354 "a name qualified with %<%D::%>", name,
12355 in_namespace);
12356 }
12357 }
12358 else if (ctype && sfk == sfk_conversion)
12359 {
12360 if (explicitp == 1)
12361 {
12362 maybe_warn_cpp0x (CPP0X_EXPLICIT_CONVERSION);
12363 explicitp = 2;
12364 }
12365 if (late_return_type_p)
12366 error ("a conversion function cannot have a trailing return type");
12367 }
12368 else if (sfk == sfk_deduction_guide)
12369 {
12370 if (explicitp == 1)
12371 explicitp = 2;
12372 }
12373
12374 tree pushed_scope = NULL_TREE;
12375 if (funcdecl_p
12376 && decl_context != FIELD
12377 && inner_declarator->u.id.qualifying_scope
12378 && CLASS_TYPE_P (inner_declarator->u.id.qualifying_scope))
12379 pushed_scope
12380 = push_scope (inner_declarator->u.id.qualifying_scope);
12381
12382 arg_types = grokparms (declarator->u.function.parameters, &parms);
12383
12384 if (pushed_scope)
12385 pop_scope (pushed_scope);
12386
12387 if (inner_declarator
12388 && inner_declarator->kind == cdk_id
12389 && inner_declarator->u.id.sfk == sfk_destructor
12390 && arg_types != void_list_node)
12391 {
12392 error_at (declarator->id_loc,
12393 "destructors may not have parameters");
12394 arg_types = void_list_node;
12395 parms = NULL_TREE;
12396 }
12397
12398 type = build_function_type (type, arg_types);
12399
12400 tree attrs = declarator->std_attributes;
12401 if (tx_qual)
12402 {
12403 tree att = build_tree_list (tx_qual, NULL_TREE);
12404 /* transaction_safe applies to the type, but
12405 transaction_safe_dynamic applies to the function. */
12406 if (is_attribute_p ("transaction_safe", tx_qual))
12407 attrs = chainon (attrs, att);
12408 else
12409 returned_attrs = chainon (returned_attrs, att);
12410 }
12411 if (attrs)
12412 /* [dcl.fct]/2:
12413
12414 The optional attribute-specifier-seq appertains to
12415 the function type. */
12416 cplus_decl_attributes (&type, attrs, 0);
12417
12418 if (raises)
12419 type = build_exception_variant (type, raises);
12420 }
12421 break;
12422
12423 case cdk_pointer:
12424 case cdk_reference:
12425 case cdk_ptrmem:
12426 /* Filter out pointers-to-references and references-to-references.
12427 We can get these if a TYPE_DECL is used. */
12428
12429 if (TYPE_REF_P (type))
12430 {
12431 if (declarator->kind != cdk_reference)
12432 {
12433 error ("cannot declare pointer to %q#T", type);
12434 type = TREE_TYPE (type);
12435 }
12436
12437 /* In C++0x, we allow reference to reference declarations
12438 that occur indirectly through typedefs [7.1.3/8 dcl.typedef]
12439 and template type arguments [14.3.1/4 temp.arg.type]. The
12440 check for direct reference to reference declarations, which
12441 are still forbidden, occurs below. Reasoning behind the change
12442 can be found in DR106, DR540, and the rvalue reference
12443 proposals. */
12444 else if (cxx_dialect == cxx98)
12445 {
12446 error ("cannot declare reference to %q#T", type);
12447 type = TREE_TYPE (type);
12448 }
12449 }
12450 else if (VOID_TYPE_P (type))
12451 {
12452 if (declarator->kind == cdk_reference)
12453 error ("cannot declare reference to %q#T", type);
12454 else if (declarator->kind == cdk_ptrmem)
12455 error ("cannot declare pointer to %q#T member", type);
12456 }
12457
12458 /* We now know that the TYPE_QUALS don't apply to the decl,
12459 but to the target of the pointer. */
12460 type_quals = TYPE_UNQUALIFIED;
12461
12462 /* This code used to handle METHOD_TYPE, but I don't think it's
12463 possible to get it here anymore. */
12464 gcc_assert (TREE_CODE (type) != METHOD_TYPE);
12465 if (declarator->kind == cdk_ptrmem
12466 && TREE_CODE (type) == FUNCTION_TYPE)
12467 {
12468 memfn_quals |= type_memfn_quals (type);
12469 type = build_memfn_type (type,
12470 declarator->u.pointer.class_type,
12471 memfn_quals,
12472 rqual);
12473 if (type == error_mark_node)
12474 return error_mark_node;
12475
12476 rqual = REF_QUAL_NONE;
12477 memfn_quals = TYPE_UNQUALIFIED;
12478 }
12479
12480 if (TREE_CODE (type) == FUNCTION_TYPE
12481 && (type_memfn_quals (type) != TYPE_UNQUALIFIED
12482 || type_memfn_rqual (type) != REF_QUAL_NONE))
12483 error (declarator->kind == cdk_reference
12484 ? G_("cannot declare reference to qualified function type %qT")
12485 : G_("cannot declare pointer to qualified function type %qT"),
12486 type);
12487
12488 /* When the pointed-to type involves components of variable size,
12489 care must be taken to ensure that the size evaluation code is
12490 emitted early enough to dominate all the possible later uses
12491 and late enough for the variables on which it depends to have
12492 been assigned.
12493
12494 This is expected to happen automatically when the pointed-to
12495 type has a name/declaration of it's own, but special attention
12496 is required if the type is anonymous.
12497
12498 We handle the NORMAL and FIELD contexts here by inserting a
12499 dummy statement that just evaluates the size at a safe point
12500 and ensures it is not deferred until e.g. within a deeper
12501 conditional context (c++/43555).
12502
12503 We expect nothing to be needed here for PARM or TYPENAME.
12504 Evaluating the size at this point for TYPENAME would
12505 actually be incorrect, as we might be in the middle of an
12506 expression with side effects on the pointed-to type size
12507 "arguments" prior to the pointer declaration point and the
12508 size evaluation could end up prior to the side effects. */
12509
12510 if (!TYPE_NAME (type)
12511 && (decl_context == NORMAL || decl_context == FIELD)
12512 && at_function_scope_p ()
12513 && variably_modified_type_p (type, NULL_TREE))
12514 {
12515 TYPE_NAME (type) = build_decl (UNKNOWN_LOCATION, TYPE_DECL,
12516 NULL_TREE, type);
12517 add_decl_expr (TYPE_NAME (type));
12518 }
12519
12520 if (declarator->kind == cdk_reference)
12521 {
12522 /* In C++0x, the type we are creating a reference to might be
12523 a typedef which is itself a reference type. In that case,
12524 we follow the reference collapsing rules in
12525 [7.1.3/8 dcl.typedef] to create the final reference type:
12526
12527 "If a typedef TD names a type that is a reference to a type
12528 T, an attempt to create the type 'lvalue reference to cv TD'
12529 creates the type 'lvalue reference to T,' while an attempt
12530 to create the type "rvalue reference to cv TD' creates the
12531 type TD."
12532 */
12533 if (VOID_TYPE_P (type))
12534 /* We already gave an error. */;
12535 else if (TYPE_REF_P (type))
12536 {
12537 if (declarator->u.reference.rvalue_ref)
12538 /* Leave type alone. */;
12539 else
12540 type = cp_build_reference_type (TREE_TYPE (type), false);
12541 }
12542 else
12543 type = cp_build_reference_type
12544 (type, declarator->u.reference.rvalue_ref);
12545
12546 /* In C++0x, we need this check for direct reference to
12547 reference declarations, which are forbidden by
12548 [8.3.2/5 dcl.ref]. Reference to reference declarations
12549 are only allowed indirectly through typedefs and template
12550 type arguments. Example:
12551
12552 void foo(int & &); // invalid ref-to-ref decl
12553
12554 typedef int & int_ref;
12555 void foo(int_ref &); // valid ref-to-ref decl
12556 */
12557 if (inner_declarator && inner_declarator->kind == cdk_reference)
12558 error ("cannot declare reference to %q#T, which is not "
12559 "a typedef or a template type argument", type);
12560 }
12561 else if (TREE_CODE (type) == METHOD_TYPE)
12562 type = build_ptrmemfunc_type (build_pointer_type (type));
12563 else if (declarator->kind == cdk_ptrmem)
12564 {
12565 gcc_assert (TREE_CODE (declarator->u.pointer.class_type)
12566 != NAMESPACE_DECL);
12567 if (declarator->u.pointer.class_type == error_mark_node)
12568 /* We will already have complained. */
12569 type = error_mark_node;
12570 else
12571 type = build_ptrmem_type (declarator->u.pointer.class_type,
12572 type);
12573 }
12574 else
12575 type = build_pointer_type (type);
12576
12577 /* Process a list of type modifier keywords (such as
12578 const or volatile) that were given inside the `*' or `&'. */
12579
12580 if (declarator->u.pointer.qualifiers)
12581 {
12582 type
12583 = cp_build_qualified_type (type,
12584 declarator->u.pointer.qualifiers);
12585 type_quals = cp_type_quals (type);
12586 }
12587
12588 /* Apply C++11 attributes to the pointer, and not to the
12589 type pointed to. This is unlike what is done for GNU
12590 attributes above. It is to comply with [dcl.ptr]/1:
12591
12592 [the optional attribute-specifier-seq (7.6.1) appertains
12593 to the pointer and not to the object pointed to]. */
12594 if (declarator->std_attributes)
12595 decl_attributes (&type, declarator->std_attributes,
12596 0);
12597
12598 ctype = NULL_TREE;
12599 break;
12600
12601 case cdk_error:
12602 break;
12603
12604 default:
12605 gcc_unreachable ();
12606 }
12607 }
12608
12609 id_loc = declarator ? declarator->id_loc : input_location;
12610
12611 /* A `constexpr' specifier used in an object declaration declares
12612 the object as `const'. */
12613 if (constexpr_p && innermost_code != cdk_function)
12614 {
12615 /* DR1688 says that a `constexpr' specifier in combination with
12616 `volatile' is valid. */
12617
12618 if (!TYPE_REF_P (type))
12619 {
12620 type_quals |= TYPE_QUAL_CONST;
12621 type = cp_build_qualified_type (type, type_quals);
12622 }
12623 }
12624
12625 if (unqualified_id && TREE_CODE (unqualified_id) == TEMPLATE_ID_EXPR
12626 && !FUNC_OR_METHOD_TYPE_P (type)
12627 && !variable_template_p (TREE_OPERAND (unqualified_id, 0)))
12628 {
12629 error ("template-id %qD used as a declarator",
12630 unqualified_id);
12631 unqualified_id = dname;
12632 }
12633
12634 /* If TYPE is a FUNCTION_TYPE, but the function name was explicitly
12635 qualified with a class-name, turn it into a METHOD_TYPE, unless
12636 we know that the function is static. We take advantage of this
12637 opportunity to do other processing that pertains to entities
12638 explicitly declared to be class members. Note that if DECLARATOR
12639 is non-NULL, we know it is a cdk_id declarator; otherwise, we
12640 would not have exited the loop above. */
12641 if (declarator
12642 && declarator->kind == cdk_id
12643 && declarator->u.id.qualifying_scope
12644 && MAYBE_CLASS_TYPE_P (declarator->u.id.qualifying_scope))
12645 {
12646 ctype = declarator->u.id.qualifying_scope;
12647 ctype = TYPE_MAIN_VARIANT (ctype);
12648 template_count = num_template_headers_for_class (ctype);
12649
12650 if (ctype == current_class_type)
12651 {
12652 if (friendp)
12653 {
12654 permerror (declspecs->locations[ds_friend],
12655 "member functions are implicitly "
12656 "friends of their class");
12657 friendp = 0;
12658 }
12659 else
12660 permerror (id_loc, "extra qualification %<%T::%> on member %qs",
12661 ctype, name);
12662 }
12663 else if (/* If the qualifying type is already complete, then we
12664 can skip the following checks. */
12665 !COMPLETE_TYPE_P (ctype)
12666 && (/* If the function is being defined, then
12667 qualifying type must certainly be complete. */
12668 funcdef_flag
12669 /* A friend declaration of "T::f" is OK, even if
12670 "T" is a template parameter. But, if this
12671 function is not a friend, the qualifying type
12672 must be a class. */
12673 || (!friendp && !CLASS_TYPE_P (ctype))
12674 /* For a declaration, the type need not be
12675 complete, if either it is dependent (since there
12676 is no meaningful definition of complete in that
12677 case) or the qualifying class is currently being
12678 defined. */
12679 || !(dependent_type_p (ctype)
12680 || currently_open_class (ctype)))
12681 /* Check that the qualifying type is complete. */
12682 && !complete_type_or_else (ctype, NULL_TREE))
12683 return error_mark_node;
12684 else if (TREE_CODE (type) == FUNCTION_TYPE)
12685 {
12686 if (current_class_type
12687 && (!friendp || funcdef_flag || initialized))
12688 {
12689 error_at (id_loc, funcdef_flag || initialized
12690 ? G_("cannot define member function %<%T::%s%> "
12691 "within %qT")
12692 : G_("cannot declare member function %<%T::%s%> "
12693 "within %qT"),
12694 ctype, name, current_class_type);
12695 return error_mark_node;
12696 }
12697 }
12698 else if (typedef_p && current_class_type)
12699 {
12700 error_at (id_loc, "cannot declare member %<%T::%s%> within %qT",
12701 ctype, name, current_class_type);
12702 return error_mark_node;
12703 }
12704 }
12705
12706 if (ctype == NULL_TREE && decl_context == FIELD && friendp == 0)
12707 ctype = current_class_type;
12708
12709 /* Now TYPE has the actual type. */
12710
12711 if (returned_attrs)
12712 {
12713 if (attrlist)
12714 *attrlist = chainon (returned_attrs, *attrlist);
12715 else
12716 attrlist = &returned_attrs;
12717 }
12718
12719 if (declarator
12720 && declarator->kind == cdk_id
12721 && declarator->std_attributes
12722 && attrlist != NULL)
12723 {
12724 /* [dcl.meaning]/1: The optional attribute-specifier-seq following
12725 a declarator-id appertains to the entity that is declared. */
12726 if (declarator->std_attributes != error_mark_node)
12727 *attrlist = chainon (*attrlist, declarator->std_attributes);
12728 else
12729 /* We should have already diagnosed the issue (c++/78344). */
12730 gcc_assert (seen_error ());
12731 }
12732
12733 /* Handle parameter packs. */
12734 if (parameter_pack_p)
12735 {
12736 if (decl_context == PARM)
12737 /* Turn the type into a pack expansion.*/
12738 type = make_pack_expansion (type);
12739 else
12740 error ("non-parameter %qs cannot be a parameter pack", name);
12741 }
12742
12743 if ((decl_context == FIELD || decl_context == PARM)
12744 && !processing_template_decl
12745 && variably_modified_type_p (type, NULL_TREE))
12746 {
12747 if (decl_context == FIELD)
12748 error_at (id_loc,
12749 "data member may not have variably modified type %qT", type);
12750 else
12751 error_at (id_loc,
12752 "parameter may not have variably modified type %qT", type);
12753 type = error_mark_node;
12754 }
12755
12756 if (explicitp == 1 || (explicitp && friendp))
12757 {
12758 /* [dcl.fct.spec] (C++11) The explicit specifier shall be used only
12759 in the declaration of a constructor or conversion function within
12760 a class definition. */
12761 if (!current_class_type)
12762 error_at (declspecs->locations[ds_explicit],
12763 "%<explicit%> outside class declaration");
12764 else if (friendp)
12765 error_at (declspecs->locations[ds_explicit],
12766 "%<explicit%> in friend declaration");
12767 else
12768 error_at (declspecs->locations[ds_explicit],
12769 "only declarations of constructors and conversion operators "
12770 "can be %<explicit%>");
12771 explicitp = 0;
12772 }
12773
12774 if (storage_class == sc_mutable)
12775 {
12776 location_t sloc = declspecs->locations[ds_storage_class];
12777 if (decl_context != FIELD || friendp)
12778 {
12779 error_at (sloc, "non-member %qs cannot be declared %<mutable%>",
12780 name);
12781 storage_class = sc_none;
12782 }
12783 else if (decl_context == TYPENAME || typedef_p)
12784 {
12785 error_at (sloc,
12786 "non-object member %qs cannot be declared %<mutable%>",
12787 name);
12788 storage_class = sc_none;
12789 }
12790 else if (FUNC_OR_METHOD_TYPE_P (type))
12791 {
12792 error_at (sloc, "function %qs cannot be declared %<mutable%>",
12793 name);
12794 storage_class = sc_none;
12795 }
12796 else if (staticp)
12797 {
12798 error_at (sloc, "%<static%> %qs cannot be declared %<mutable%>",
12799 name);
12800 storage_class = sc_none;
12801 }
12802 else if (type_quals & TYPE_QUAL_CONST)
12803 {
12804 error_at (sloc, "%<const%> %qs cannot be declared %<mutable%>",
12805 name);
12806 storage_class = sc_none;
12807 }
12808 else if (TYPE_REF_P (type))
12809 {
12810 permerror (sloc, "reference %qs cannot be declared %<mutable%>",
12811 name);
12812 storage_class = sc_none;
12813 }
12814 }
12815
12816 /* If this is declaring a typedef name, return a TYPE_DECL. */
12817 if (typedef_p && decl_context != TYPENAME)
12818 {
12819 bool alias_p = decl_spec_seq_has_spec_p (declspecs, ds_alias);
12820 tree decl;
12821
12822 if (funcdef_flag)
12823 {
12824 if (decl_context == NORMAL)
12825 error_at (id_loc,
12826 "typedef may not be a function definition");
12827 else
12828 error_at (id_loc,
12829 "typedef may not be a member function definition");
12830 return error_mark_node;
12831 }
12832
12833 /* This declaration:
12834
12835 typedef void f(int) const;
12836
12837 declares a function type which is not a member of any
12838 particular class, but which is cv-qualified; for
12839 example "f S::*" declares a pointer to a const-qualified
12840 member function of S. We record the cv-qualification in the
12841 function type. */
12842 if ((rqual || memfn_quals) && TREE_CODE (type) == FUNCTION_TYPE)
12843 {
12844 type = apply_memfn_quals (type, memfn_quals, rqual);
12845
12846 /* We have now dealt with these qualifiers. */
12847 memfn_quals = TYPE_UNQUALIFIED;
12848 rqual = REF_QUAL_NONE;
12849 }
12850
12851 if (type_uses_auto (type))
12852 {
12853 if (alias_p)
12854 error_at (declspecs->locations[ds_type_spec],
12855 "%<auto%> not allowed in alias declaration");
12856 else
12857 error_at (declspecs->locations[ds_type_spec],
12858 "typedef declared %<auto%>");
12859 type = error_mark_node;
12860 }
12861
12862 if (reqs)
12863 error_at (location_of (reqs), "requires-clause on typedef");
12864
12865 if (id_declarator && declarator->u.id.qualifying_scope)
12866 {
12867 error_at (id_loc, "typedef name may not be a nested-name-specifier");
12868 type = error_mark_node;
12869 }
12870
12871 if (decl_context == FIELD)
12872 decl = build_lang_decl_loc (id_loc, TYPE_DECL, unqualified_id, type);
12873 else
12874 decl = build_decl (id_loc, TYPE_DECL, unqualified_id, type);
12875
12876 if (decl_context != FIELD)
12877 {
12878 if (!current_function_decl)
12879 DECL_CONTEXT (decl) = FROB_CONTEXT (current_namespace);
12880 else if (DECL_MAYBE_IN_CHARGE_CDTOR_P (current_function_decl))
12881 /* The TYPE_DECL is "abstract" because there will be
12882 clones of this constructor/destructor, and there will
12883 be copies of this TYPE_DECL generated in those
12884 clones. The decloning optimization (for space) may
12885 revert this subsequently if it determines that
12886 the clones should share a common implementation. */
12887 DECL_ABSTRACT_P (decl) = true;
12888 }
12889 else if (current_class_type
12890 && constructor_name_p (unqualified_id, current_class_type))
12891 permerror (id_loc, "ISO C++ forbids nested type %qD with same name "
12892 "as enclosing class",
12893 unqualified_id);
12894
12895 /* If the user declares "typedef struct {...} foo" then the
12896 struct will have an anonymous name. Fill that name in now.
12897 Nothing can refer to it, so nothing needs know about the name
12898 change. */
12899 if (type != error_mark_node
12900 && unqualified_id
12901 && TYPE_NAME (type)
12902 && TREE_CODE (TYPE_NAME (type)) == TYPE_DECL
12903 && TYPE_UNNAMED_P (type)
12904 && declspecs->type_definition_p
12905 && attributes_naming_typedef_ok (*attrlist)
12906 && cp_type_quals (type) == TYPE_UNQUALIFIED)
12907 name_unnamed_type (type, decl);
12908
12909 if (signed_p
12910 || (typedef_decl && C_TYPEDEF_EXPLICITLY_SIGNED (typedef_decl)))
12911 C_TYPEDEF_EXPLICITLY_SIGNED (decl) = 1;
12912
12913 bad_specifiers (decl, BSP_TYPE, virtualp,
12914 memfn_quals != TYPE_UNQUALIFIED,
12915 inlinep, friendp, raises != NULL_TREE,
12916 declspecs->locations);
12917
12918 if (alias_p)
12919 /* Acknowledge that this was written:
12920 `using analias = atype;'. */
12921 TYPE_DECL_ALIAS_P (decl) = 1;
12922
12923 return decl;
12924 }
12925
12926 /* Detect the case of an array type of unspecified size
12927 which came, as such, direct from a typedef name.
12928 We must copy the type, so that the array's domain can be
12929 individually set by the object's initializer. */
12930
12931 if (type && typedef_type
12932 && TREE_CODE (type) == ARRAY_TYPE && !TYPE_DOMAIN (type)
12933 && TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (typedef_type))
12934 type = build_cplus_array_type (TREE_TYPE (type), NULL_TREE);
12935
12936 /* Detect where we're using a typedef of function type to declare a
12937 function. PARMS will not be set, so we must create it now. */
12938
12939 if (type == typedef_type && TREE_CODE (type) == FUNCTION_TYPE)
12940 {
12941 tree decls = NULL_TREE;
12942 tree args;
12943
12944 for (args = TYPE_ARG_TYPES (type);
12945 args && args != void_list_node;
12946 args = TREE_CHAIN (args))
12947 {
12948 tree decl = cp_build_parm_decl (NULL_TREE, NULL_TREE,
12949 TREE_VALUE (args));
12950
12951 DECL_CHAIN (decl) = decls;
12952 decls = decl;
12953 }
12954
12955 parms = nreverse (decls);
12956
12957 if (decl_context != TYPENAME)
12958 {
12959 /* The qualifiers on the function type become the qualifiers on
12960 the non-static member function. */
12961 memfn_quals |= type_memfn_quals (type);
12962 rqual = type_memfn_rqual (type);
12963 type_quals = TYPE_UNQUALIFIED;
12964 raises = TYPE_RAISES_EXCEPTIONS (type);
12965 }
12966 }
12967
12968 /* If this is a type name (such as, in a cast or sizeof),
12969 compute the type and return it now. */
12970
12971 if (decl_context == TYPENAME)
12972 {
12973 /* Note that here we don't care about type_quals. */
12974
12975 /* Special case: "friend class foo" looks like a TYPENAME context. */
12976 if (friendp)
12977 {
12978 if (inlinep)
12979 {
12980 error ("%<inline%> specified for friend class declaration");
12981 inlinep = 0;
12982 }
12983
12984 if (!current_aggr)
12985 {
12986 /* Don't allow friend declaration without a class-key. */
12987 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
12988 permerror (input_location, "template parameters cannot be friends");
12989 else if (TREE_CODE (type) == TYPENAME_TYPE)
12990 permerror (input_location, "friend declaration requires class-key, "
12991 "i.e. %<friend class %T::%D%>",
12992 TYPE_CONTEXT (type), TYPENAME_TYPE_FULLNAME (type));
12993 else
12994 permerror (input_location, "friend declaration requires class-key, "
12995 "i.e. %<friend %#T%>",
12996 type);
12997 }
12998
12999 /* Only try to do this stuff if we didn't already give up. */
13000 if (type != integer_type_node)
13001 {
13002 /* A friendly class? */
13003 if (current_class_type)
13004 make_friend_class (current_class_type, TYPE_MAIN_VARIANT (type),
13005 /*complain=*/true);
13006 else
13007 error ("trying to make class %qT a friend of global scope",
13008 type);
13009
13010 type = void_type_node;
13011 }
13012 }
13013 else if (memfn_quals || rqual)
13014 {
13015 if (ctype == NULL_TREE
13016 && TREE_CODE (type) == METHOD_TYPE)
13017 ctype = TYPE_METHOD_BASETYPE (type);
13018
13019 if (ctype)
13020 type = build_memfn_type (type, ctype, memfn_quals, rqual);
13021 /* Core issue #547: need to allow this in template type args.
13022 Allow it in general in C++11 for alias-declarations. */
13023 else if ((template_type_arg || cxx_dialect >= cxx11)
13024 && TREE_CODE (type) == FUNCTION_TYPE)
13025 type = apply_memfn_quals (type, memfn_quals, rqual);
13026 else
13027 error ("invalid qualifiers on non-member function type");
13028 }
13029
13030 if (reqs)
13031 error_at (location_of (reqs), "requires-clause on type-id");
13032
13033 return type;
13034 }
13035 else if (unqualified_id == NULL_TREE && decl_context != PARM
13036 && decl_context != CATCHPARM
13037 && TREE_CODE (type) != UNION_TYPE
13038 && ! bitfield
13039 && innermost_code != cdk_decomp)
13040 {
13041 error ("abstract declarator %qT used as declaration", type);
13042 return error_mark_node;
13043 }
13044
13045 if (!FUNC_OR_METHOD_TYPE_P (type))
13046 {
13047 /* Only functions may be declared using an operator-function-id. */
13048 if (dname && IDENTIFIER_ANY_OP_P (dname))
13049 {
13050 error_at (id_loc, "declaration of %qD as non-function", dname);
13051 return error_mark_node;
13052 }
13053
13054 if (reqs)
13055 error_at (location_of (reqs),
13056 "requires-clause on declaration of non-function type %qT",
13057 type);
13058 }
13059
13060 /* We don't check parameter types here because we can emit a better
13061 error message later. */
13062 if (decl_context != PARM)
13063 {
13064 type = check_var_type (unqualified_id, type, id_loc);
13065 if (type == error_mark_node)
13066 return error_mark_node;
13067 }
13068
13069 /* Now create the decl, which may be a VAR_DECL, a PARM_DECL
13070 or a FUNCTION_DECL, depending on DECL_CONTEXT and TYPE. */
13071
13072 if (decl_context == PARM || decl_context == CATCHPARM)
13073 {
13074 if (ctype || in_namespace)
13075 error ("cannot use %<::%> in parameter declaration");
13076
13077 tree auto_node = type_uses_auto (type);
13078 if (auto_node && !(cxx_dialect >= cxx17 && template_parm_flag))
13079 {
13080 if (cxx_dialect >= cxx14)
13081 {
13082 if (decl_context == PARM && AUTO_IS_DECLTYPE (auto_node))
13083 error_at (typespec_loc,
13084 "cannot declare a parameter with %<decltype(auto)%>");
13085 else
13086 error_at (typespec_loc,
13087 "%<auto%> parameter not permitted in this context");
13088 }
13089 else
13090 error_at (typespec_loc, "parameter declared %<auto%>");
13091 type = error_mark_node;
13092 }
13093
13094 /* A parameter declared as an array of T is really a pointer to T.
13095 One declared as a function is really a pointer to a function.
13096 One declared as a member is really a pointer to member. */
13097
13098 if (TREE_CODE (type) == ARRAY_TYPE)
13099 {
13100 /* Transfer const-ness of array into that of type pointed to. */
13101 type = build_pointer_type (TREE_TYPE (type));
13102 type_quals = TYPE_UNQUALIFIED;
13103 array_parameter_p = true;
13104 }
13105 else if (TREE_CODE (type) == FUNCTION_TYPE)
13106 type = build_pointer_type (type);
13107 }
13108
13109 if (ctype && TREE_CODE (type) == FUNCTION_TYPE && staticp < 2
13110 && !(unqualified_id
13111 && identifier_p (unqualified_id)
13112 && IDENTIFIER_NEWDEL_OP_P (unqualified_id)))
13113 {
13114 cp_cv_quals real_quals = memfn_quals;
13115 if (cxx_dialect < cxx14 && constexpr_p
13116 && sfk != sfk_constructor && sfk != sfk_destructor)
13117 real_quals |= TYPE_QUAL_CONST;
13118 type = build_memfn_type (type, ctype, real_quals, rqual);
13119 }
13120
13121 {
13122 tree decl = NULL_TREE;
13123
13124 if (decl_context == PARM)
13125 {
13126 decl = cp_build_parm_decl (NULL_TREE, unqualified_id, type);
13127 DECL_ARRAY_PARAMETER_P (decl) = array_parameter_p;
13128
13129 bad_specifiers (decl, BSP_PARM, virtualp,
13130 memfn_quals != TYPE_UNQUALIFIED,
13131 inlinep, friendp, raises != NULL_TREE,
13132 declspecs->locations);
13133 }
13134 else if (decl_context == FIELD)
13135 {
13136 if (!staticp && !friendp && TREE_CODE (type) != METHOD_TYPE)
13137 if (tree auto_node = type_uses_auto (type))
13138 {
13139 location_t tloc = declspecs->locations[ds_type_spec];
13140 if (CLASS_PLACEHOLDER_TEMPLATE (auto_node))
13141 error_at (tloc, "invalid use of template-name %qE without an "
13142 "argument list",
13143 CLASS_PLACEHOLDER_TEMPLATE (auto_node));
13144 else
13145 error_at (tloc, "non-static data member declared with "
13146 "placeholder %qT", auto_node);
13147 type = error_mark_node;
13148 }
13149
13150 /* The C99 flexible array extension. */
13151 if (!staticp && TREE_CODE (type) == ARRAY_TYPE
13152 && TYPE_DOMAIN (type) == NULL_TREE)
13153 {
13154 if (ctype
13155 && (TREE_CODE (ctype) == UNION_TYPE
13156 || TREE_CODE (ctype) == QUAL_UNION_TYPE))
13157 {
13158 error_at (id_loc, "flexible array member in union");
13159 type = error_mark_node;
13160 }
13161 else
13162 {
13163 /* Array is a flexible member. */
13164 if (name)
13165 pedwarn (id_loc, OPT_Wpedantic,
13166 "ISO C++ forbids flexible array member %qs", name);
13167 else
13168 pedwarn (input_location, OPT_Wpedantic,
13169 "ISO C++ forbids flexible array members");
13170
13171 /* Flexible array member has a null domain. */
13172 type = build_cplus_array_type (TREE_TYPE (type), NULL_TREE);
13173 }
13174 }
13175
13176 if (type == error_mark_node)
13177 {
13178 /* Happens when declaring arrays of sizes which
13179 are error_mark_node, for example. */
13180 decl = NULL_TREE;
13181 }
13182 else if (in_namespace && !friendp)
13183 {
13184 /* Something like struct S { int N::j; }; */
13185 error_at (id_loc, "invalid use of %<::%>");
13186 return error_mark_node;
13187 }
13188 else if (FUNC_OR_METHOD_TYPE_P (type) && unqualified_id)
13189 {
13190 int publicp = 0;
13191 tree function_context;
13192
13193 if (friendp == 0)
13194 {
13195 /* This should never happen in pure C++ (the check
13196 could be an assert). It could happen in
13197 Objective-C++ if someone writes invalid code that
13198 uses a function declaration for an instance
13199 variable or property (instance variables and
13200 properties are parsed as FIELD_DECLs, but they are
13201 part of an Objective-C class, not a C++ class).
13202 That code is invalid and is caught by this
13203 check. */
13204 if (!ctype)
13205 {
13206 error ("declaration of function %qD in invalid context",
13207 unqualified_id);
13208 return error_mark_node;
13209 }
13210
13211 /* ``A union may [ ... ] not [ have ] virtual functions.''
13212 ARM 9.5 */
13213 if (virtualp && TREE_CODE (ctype) == UNION_TYPE)
13214 {
13215 error_at (declspecs->locations[ds_virtual],
13216 "function %qD declared %<virtual%> inside a union",
13217 unqualified_id);
13218 return error_mark_node;
13219 }
13220
13221 if (virtualp
13222 && identifier_p (unqualified_id)
13223 && IDENTIFIER_NEWDEL_OP_P (unqualified_id))
13224 {
13225 error_at (declspecs->locations[ds_virtual],
13226 "%qD cannot be declared %<virtual%>, since it "
13227 "is always static", unqualified_id);
13228 virtualp = 0;
13229 }
13230 }
13231
13232 /* Check that the name used for a destructor makes sense. */
13233 if (sfk == sfk_destructor)
13234 {
13235 tree uqname = id_declarator->u.id.unqualified_name;
13236
13237 if (!ctype)
13238 {
13239 gcc_assert (friendp);
13240 error_at (id_loc, "expected qualified name in friend "
13241 "declaration for destructor %qD", uqname);
13242 return error_mark_node;
13243 }
13244
13245 if (!check_dtor_name (ctype, TREE_OPERAND (uqname, 0)))
13246 {
13247 error_at (id_loc, "declaration of %qD as member of %qT",
13248 uqname, ctype);
13249 return error_mark_node;
13250 }
13251 if (concept_p)
13252 {
13253 error_at (declspecs->locations[ds_concept],
13254 "a destructor cannot be %qs", "concept");
13255 return error_mark_node;
13256 }
13257 if (constexpr_p && cxx_dialect < cxx2a)
13258 {
13259 error_at (declspecs->locations[ds_constexpr],
13260 "%<constexpr%> destructors only available"
13261 " with %<-std=c++2a%> or %<-std=gnu++2a%>");
13262 return error_mark_node;
13263 }
13264 if (consteval_p)
13265 {
13266 error_at (declspecs->locations[ds_consteval],
13267 "a destructor cannot be %qs", "consteval");
13268 return error_mark_node;
13269 }
13270 }
13271 else if (sfk == sfk_constructor && friendp && !ctype)
13272 {
13273 error ("expected qualified name in friend declaration "
13274 "for constructor %qD",
13275 id_declarator->u.id.unqualified_name);
13276 return error_mark_node;
13277 }
13278 if (sfk == sfk_constructor)
13279 if (concept_p)
13280 {
13281 error_at (declspecs->locations[ds_concept],
13282 "a constructor cannot be %<concept%>");
13283 return error_mark_node;
13284 }
13285 if (concept_p)
13286 {
13287 error_at (declspecs->locations[ds_concept],
13288 "a concept cannot be a member function");
13289 concept_p = false;
13290 }
13291 else if (consteval_p
13292 && identifier_p (unqualified_id)
13293 && IDENTIFIER_NEWDEL_OP_P (unqualified_id))
13294 {
13295 error_at (declspecs->locations[ds_consteval],
13296 "%qD cannot be %qs", unqualified_id, "consteval");
13297 consteval_p = false;
13298 }
13299
13300 if (TREE_CODE (unqualified_id) == TEMPLATE_ID_EXPR)
13301 {
13302 tree tmpl = TREE_OPERAND (unqualified_id, 0);
13303 if (variable_template_p (tmpl))
13304 {
13305 error_at (id_loc, "specialization of variable template "
13306 "%qD declared as function", tmpl);
13307 inform (DECL_SOURCE_LOCATION (tmpl),
13308 "variable template declared here");
13309 return error_mark_node;
13310 }
13311 }
13312
13313 /* Tell grokfndecl if it needs to set TREE_PUBLIC on the node. */
13314 function_context
13315 = (ctype != NULL_TREE
13316 ? decl_function_context (TYPE_MAIN_DECL (ctype)) : NULL_TREE);
13317 publicp = ((! friendp || ! staticp)
13318 && function_context == NULL_TREE);
13319
13320 decl = grokfndecl (ctype, type,
13321 TREE_CODE (unqualified_id) != TEMPLATE_ID_EXPR
13322 ? unqualified_id : dname,
13323 parms,
13324 unqualified_id,
13325 declspecs,
13326 reqs,
13327 virtualp, flags, memfn_quals, rqual, raises,
13328 friendp ? -1 : 0, friendp, publicp,
13329 inlinep | (2 * constexpr_p) | (4 * concept_p)
13330 | (8 * consteval_p),
13331 initialized == SD_DELETED, sfk,
13332 funcdef_flag, late_return_type_p,
13333 initialized,
13334 template_count, in_namespace,
13335 attrlist, id_loc);
13336 decl = set_virt_specifiers (decl, virt_specifiers);
13337 if (decl == NULL_TREE)
13338 return error_mark_node;
13339 #if 0
13340 /* This clobbers the attrs stored in `decl' from `attrlist'. */
13341 /* The decl and setting of decl_attr is also turned off. */
13342 decl = build_decl_attribute_variant (decl, decl_attr);
13343 #endif
13344
13345 /* [class.conv.ctor]
13346
13347 A constructor declared without the function-specifier
13348 explicit that can be called with a single parameter
13349 specifies a conversion from the type of its first
13350 parameter to the type of its class. Such a constructor
13351 is called a converting constructor. */
13352 if (explicitp == 2)
13353 DECL_NONCONVERTING_P (decl) = 1;
13354
13355 if (declspecs->explicit_specifier)
13356 store_explicit_specifier (decl, declspecs->explicit_specifier);
13357 }
13358 else if (!staticp
13359 && ((current_class_type
13360 && same_type_p (type, current_class_type))
13361 || (!dependent_type_p (type)
13362 && !COMPLETE_TYPE_P (complete_type (type))
13363 && (!complete_or_array_type_p (type)
13364 || initialized == 0))))
13365 {
13366 if (TREE_CODE (type) != ARRAY_TYPE
13367 || !COMPLETE_TYPE_P (TREE_TYPE (type)))
13368 {
13369 if (unqualified_id)
13370 {
13371 error_at (id_loc, "field %qD has incomplete type %qT",
13372 unqualified_id, type);
13373 cxx_incomplete_type_inform (strip_array_types (type));
13374 }
13375 else
13376 error ("name %qT has incomplete type", type);
13377
13378 type = error_mark_node;
13379 decl = NULL_TREE;
13380 }
13381 }
13382 else if (!verify_type_context (input_location,
13383 staticp
13384 ? TCTX_STATIC_STORAGE
13385 : TCTX_FIELD, type))
13386 {
13387 type = error_mark_node;
13388 decl = NULL_TREE;
13389 }
13390 else
13391 {
13392 if (friendp)
13393 {
13394 if (unqualified_id)
13395 error_at (id_loc,
13396 "%qE is neither function nor member function; "
13397 "cannot be declared friend", unqualified_id);
13398 else
13399 error ("unnamed field is neither function nor member "
13400 "function; cannot be declared friend");
13401 return error_mark_node;
13402 }
13403 decl = NULL_TREE;
13404 }
13405
13406 if (friendp)
13407 {
13408 /* Friends are treated specially. */
13409 if (ctype == current_class_type)
13410 ; /* We already issued a permerror. */
13411 else if (decl && DECL_NAME (decl))
13412 {
13413 if (initialized)
13414 /* Kludge: We need funcdef_flag to be true in do_friend for
13415 in-class defaulted functions, but that breaks grokfndecl.
13416 So set it here. */
13417 funcdef_flag = true;
13418 if (template_class_depth (current_class_type) == 0)
13419 {
13420 decl = check_explicit_specialization
13421 (unqualified_id, decl, template_count,
13422 2 * funcdef_flag + 4);
13423 if (decl == error_mark_node)
13424 return error_mark_node;
13425 }
13426
13427 decl = do_friend (ctype, unqualified_id, decl,
13428 *attrlist, flags,
13429 funcdef_flag);
13430 return decl;
13431 }
13432 else
13433 return error_mark_node;
13434 }
13435
13436 /* Structure field. It may not be a function, except for C++. */
13437
13438 if (decl == NULL_TREE)
13439 {
13440 if (staticp)
13441 {
13442 /* C++ allows static class members. All other work
13443 for this is done by grokfield. */
13444 decl = build_lang_decl_loc (id_loc, VAR_DECL,
13445 unqualified_id, type);
13446 set_linkage_for_static_data_member (decl);
13447 if (concept_p)
13448 error_at (declspecs->locations[ds_concept],
13449 "static data member %qE declared %qs",
13450 unqualified_id, "concept");
13451 else if (constexpr_p && !initialized)
13452 {
13453 error_at (DECL_SOURCE_LOCATION (decl),
13454 "%<constexpr%> static data member %qD must "
13455 "have an initializer", decl);
13456 constexpr_p = false;
13457 }
13458 if (consteval_p)
13459 error_at (declspecs->locations[ds_consteval],
13460 "static data member %qE declared %qs",
13461 unqualified_id, "consteval");
13462
13463 if (inlinep)
13464 mark_inline_variable (decl, declspecs->locations[ds_inline]);
13465
13466 if (!DECL_VAR_DECLARED_INLINE_P (decl)
13467 && !(cxx_dialect >= cxx17 && constexpr_p))
13468 /* Even if there is an in-class initialization, DECL
13469 is considered undefined until an out-of-class
13470 definition is provided, unless this is an inline
13471 variable. */
13472 DECL_EXTERNAL (decl) = 1;
13473
13474 if (thread_p)
13475 {
13476 CP_DECL_THREAD_LOCAL_P (decl) = true;
13477 if (!processing_template_decl)
13478 set_decl_tls_model (decl, decl_default_tls_model (decl));
13479 if (declspecs->gnu_thread_keyword_p)
13480 SET_DECL_GNU_TLS_P (decl);
13481 }
13482 }
13483 else
13484 {
13485 if (concept_p)
13486 {
13487 error_at (declspecs->locations[ds_concept],
13488 "non-static data member %qE declared %qs",
13489 unqualified_id, "concept");
13490 concept_p = false;
13491 constexpr_p = false;
13492 }
13493 else if (constexpr_p)
13494 {
13495 error_at (declspecs->locations[ds_constexpr],
13496 "non-static data member %qE declared %qs",
13497 unqualified_id, "constexpr");
13498 constexpr_p = false;
13499 }
13500 if (constinit_p)
13501 {
13502 error_at (declspecs->locations[ds_constinit],
13503 "non-static data member %qE declared %qs",
13504 unqualified_id, "constinit");
13505 constinit_p = false;
13506 }
13507 if (consteval_p)
13508 {
13509 error_at (declspecs->locations[ds_consteval],
13510 "non-static data member %qE declared %qs",
13511 unqualified_id, "consteval");
13512 consteval_p = false;
13513 }
13514 decl = build_decl (id_loc, FIELD_DECL, unqualified_id, type);
13515 DECL_NONADDRESSABLE_P (decl) = bitfield;
13516 if (bitfield && !unqualified_id)
13517 {
13518 TREE_NO_WARNING (decl) = 1;
13519 DECL_PADDING_P (decl) = 1;
13520 }
13521
13522 if (storage_class == sc_mutable)
13523 {
13524 DECL_MUTABLE_P (decl) = 1;
13525 storage_class = sc_none;
13526 }
13527
13528 if (initialized)
13529 {
13530 /* An attempt is being made to initialize a non-static
13531 member. This is new in C++11. */
13532 maybe_warn_cpp0x (CPP0X_NSDMI);
13533
13534 /* If this has been parsed with static storage class, but
13535 errors forced staticp to be cleared, ensure NSDMI is
13536 not present. */
13537 if (declspecs->storage_class == sc_static)
13538 DECL_INITIAL (decl) = error_mark_node;
13539 }
13540 }
13541
13542 bad_specifiers (decl, BSP_FIELD, virtualp,
13543 memfn_quals != TYPE_UNQUALIFIED,
13544 staticp ? false : inlinep, friendp,
13545 raises != NULL_TREE,
13546 declspecs->locations);
13547 }
13548 }
13549 else if (FUNC_OR_METHOD_TYPE_P (type))
13550 {
13551 tree original_name;
13552 int publicp = 0;
13553
13554 if (!unqualified_id)
13555 return error_mark_node;
13556
13557 if (TREE_CODE (unqualified_id) == TEMPLATE_ID_EXPR)
13558 original_name = dname;
13559 else
13560 original_name = unqualified_id;
13561 // FIXME:gcc_assert (original_name == dname);
13562
13563 if (storage_class == sc_auto)
13564 error_at (declspecs->locations[ds_storage_class],
13565 "storage class %<auto%> invalid for function %qs", name);
13566 else if (storage_class == sc_register)
13567 error_at (declspecs->locations[ds_storage_class],
13568 "storage class %<register%> invalid for function %qs",
13569 name);
13570 else if (thread_p)
13571 {
13572 if (declspecs->gnu_thread_keyword_p)
13573 error_at (declspecs->locations[ds_thread],
13574 "storage class %<__thread%> invalid for function %qs",
13575 name);
13576 else
13577 error_at (declspecs->locations[ds_thread],
13578 "storage class %<thread_local%> invalid for "
13579 "function %qs", name);
13580 }
13581
13582 if (virt_specifiers)
13583 error ("virt-specifiers in %qs not allowed outside a class "
13584 "definition", name);
13585 /* Function declaration not at top level.
13586 Storage classes other than `extern' are not allowed
13587 and `extern' makes no difference. */
13588 if (! toplevel_bindings_p ()
13589 && (storage_class == sc_static
13590 || decl_spec_seq_has_spec_p (declspecs, ds_inline))
13591 && pedantic)
13592 {
13593 if (storage_class == sc_static)
13594 pedwarn (declspecs->locations[ds_storage_class], OPT_Wpedantic,
13595 "%<static%> specifier invalid for function %qs "
13596 "declared out of global scope", name);
13597 else
13598 pedwarn (declspecs->locations[ds_inline], OPT_Wpedantic,
13599 "%<inline%> specifier invalid for function %qs "
13600 "declared out of global scope", name);
13601 }
13602
13603 if (ctype == NULL_TREE)
13604 {
13605 if (virtualp)
13606 {
13607 error ("virtual non-class function %qs", name);
13608 virtualp = 0;
13609 }
13610 else if (sfk == sfk_constructor
13611 || sfk == sfk_destructor)
13612 {
13613 error (funcdef_flag
13614 ? G_("%qs defined in a non-class scope")
13615 : G_("%qs declared in a non-class scope"), name);
13616 sfk = sfk_none;
13617 }
13618 }
13619 if (consteval_p
13620 && identifier_p (unqualified_id)
13621 && IDENTIFIER_NEWDEL_OP_P (unqualified_id))
13622 {
13623 error_at (declspecs->locations[ds_consteval],
13624 "%qD cannot be %qs", unqualified_id, "consteval");
13625 consteval_p = false;
13626 }
13627
13628 /* Record whether the function is public. */
13629 publicp = (ctype != NULL_TREE
13630 || storage_class != sc_static);
13631
13632 decl = grokfndecl (ctype, type, original_name, parms, unqualified_id,
13633 declspecs,
13634 reqs, virtualp, flags, memfn_quals, rqual, raises,
13635 1, friendp,
13636 publicp,
13637 inlinep | (2 * constexpr_p) | (4 * concept_p)
13638 | (8 * consteval_p),
13639 initialized == SD_DELETED,
13640 sfk,
13641 funcdef_flag,
13642 late_return_type_p,
13643 initialized,
13644 template_count, in_namespace, attrlist,
13645 id_loc);
13646 if (decl == NULL_TREE)
13647 return error_mark_node;
13648
13649 if (explicitp == 2)
13650 DECL_NONCONVERTING_P (decl) = 1;
13651 if (staticp == 1)
13652 {
13653 int invalid_static = 0;
13654
13655 /* Don't allow a static member function in a class, and forbid
13656 declaring main to be static. */
13657 if (TREE_CODE (type) == METHOD_TYPE)
13658 {
13659 permerror (input_location, "cannot declare member function %qD to have "
13660 "static linkage", decl);
13661 invalid_static = 1;
13662 }
13663 else if (current_function_decl)
13664 {
13665 /* 7.1.1: There can be no static function declarations within a
13666 block. */
13667 error_at (declspecs->locations[ds_storage_class],
13668 "cannot declare static function inside another function");
13669 invalid_static = 1;
13670 }
13671
13672 if (invalid_static)
13673 {
13674 staticp = 0;
13675 storage_class = sc_none;
13676 }
13677 }
13678 }
13679 else
13680 {
13681 /* It's a variable. */
13682
13683 /* An uninitialized decl with `extern' is a reference. */
13684 decl = grokvardecl (type, dname, unqualified_id,
13685 declspecs,
13686 initialized,
13687 type_quals,
13688 inlinep,
13689 concept_p,
13690 template_count,
13691 ctype ? ctype : in_namespace,
13692 id_loc);
13693 if (decl == NULL_TREE)
13694 return error_mark_node;
13695
13696 bad_specifiers (decl, BSP_VAR, virtualp,
13697 memfn_quals != TYPE_UNQUALIFIED,
13698 inlinep, friendp, raises != NULL_TREE,
13699 declspecs->locations);
13700
13701 if (ctype)
13702 {
13703 DECL_CONTEXT (decl) = ctype;
13704 if (staticp == 1)
13705 {
13706 permerror (declspecs->locations[ds_storage_class],
13707 "%<static%> may not be used when defining "
13708 "(as opposed to declaring) a static data member");
13709 staticp = 0;
13710 storage_class = sc_none;
13711 }
13712 if (storage_class == sc_register && TREE_STATIC (decl))
13713 {
13714 error ("static member %qD declared %<register%>", decl);
13715 storage_class = sc_none;
13716 }
13717 if (storage_class == sc_extern && pedantic)
13718 {
13719 pedwarn (input_location, OPT_Wpedantic,
13720 "cannot explicitly declare member %q#D to have "
13721 "extern linkage", decl);
13722 storage_class = sc_none;
13723 }
13724 }
13725 else if (constexpr_p && DECL_EXTERNAL (decl))
13726 {
13727 error_at (DECL_SOURCE_LOCATION (decl),
13728 "declaration of %<constexpr%> variable %qD "
13729 "is not a definition", decl);
13730 constexpr_p = false;
13731 }
13732 if (consteval_p)
13733 {
13734 error_at (DECL_SOURCE_LOCATION (decl),
13735 "a variable cannot be declared %<consteval%>");
13736 consteval_p = false;
13737 }
13738
13739 if (inlinep)
13740 mark_inline_variable (decl, declspecs->locations[ds_inline]);
13741 if (innermost_code == cdk_decomp)
13742 {
13743 gcc_assert (declarator && declarator->kind == cdk_decomp);
13744 DECL_SOURCE_LOCATION (decl) = id_loc;
13745 DECL_ARTIFICIAL (decl) = 1;
13746 fit_decomposition_lang_decl (decl, NULL_TREE);
13747 }
13748 }
13749
13750 if (VAR_P (decl) && !initialized)
13751 if (tree auto_node = type_uses_auto (type))
13752 if (!CLASS_PLACEHOLDER_TEMPLATE (auto_node))
13753 {
13754 location_t loc = declspecs->locations[ds_type_spec];
13755 error_at (loc, "declaration of %q#D has no initializer", decl);
13756 TREE_TYPE (decl) = error_mark_node;
13757 }
13758
13759 if (storage_class == sc_extern && initialized && !funcdef_flag)
13760 {
13761 if (toplevel_bindings_p ())
13762 {
13763 /* It's common practice (and completely valid) to have a const
13764 be initialized and declared extern. */
13765 if (!(type_quals & TYPE_QUAL_CONST))
13766 warning_at (DECL_SOURCE_LOCATION (decl), 0,
13767 "%qs initialized and declared %<extern%>", name);
13768 }
13769 else
13770 {
13771 error_at (DECL_SOURCE_LOCATION (decl),
13772 "%qs has both %<extern%> and initializer", name);
13773 return error_mark_node;
13774 }
13775 }
13776
13777 /* Record `register' declaration for warnings on &
13778 and in case doing stupid register allocation. */
13779
13780 if (storage_class == sc_register)
13781 {
13782 DECL_REGISTER (decl) = 1;
13783 /* Warn about register storage specifiers on PARM_DECLs. */
13784 if (TREE_CODE (decl) == PARM_DECL)
13785 {
13786 if (cxx_dialect >= cxx17)
13787 pedwarn (DECL_SOURCE_LOCATION (decl), OPT_Wregister,
13788 "ISO C++17 does not allow %<register%> storage "
13789 "class specifier");
13790 else
13791 warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wregister,
13792 "%<register%> storage class specifier used");
13793 }
13794 }
13795 else if (storage_class == sc_extern)
13796 DECL_THIS_EXTERN (decl) = 1;
13797 else if (storage_class == sc_static)
13798 DECL_THIS_STATIC (decl) = 1;
13799
13800 /* Set constexpr flag on vars (functions got it in grokfndecl). */
13801 if (constexpr_p && VAR_P (decl))
13802 DECL_DECLARED_CONSTEXPR_P (decl) = true;
13803
13804 /* Record constancy and volatility on the DECL itself . There's
13805 no need to do this when processing a template; we'll do this
13806 for the instantiated declaration based on the type of DECL. */
13807 if (!processing_template_decl)
13808 cp_apply_type_quals_to_decl (type_quals, decl);
13809
13810 return decl;
13811 }
13812 }
13813
13814 /* Subroutine of start_function. Ensure that each of the parameter
13815 types (as listed in PARMS) is complete, as is required for a
13816 function definition. */
13817
13818 static void
require_complete_types_for_parms(tree parms)13819 require_complete_types_for_parms (tree parms)
13820 {
13821 for (; parms; parms = DECL_CHAIN (parms))
13822 {
13823 if (dependent_type_p (TREE_TYPE (parms)))
13824 continue;
13825 if (!VOID_TYPE_P (TREE_TYPE (parms))
13826 && complete_type_or_else (TREE_TYPE (parms), parms))
13827 {
13828 relayout_decl (parms);
13829 DECL_ARG_TYPE (parms) = type_passed_as (TREE_TYPE (parms));
13830
13831 maybe_warn_parm_abi (TREE_TYPE (parms),
13832 DECL_SOURCE_LOCATION (parms));
13833 }
13834 else
13835 /* grokparms or complete_type_or_else will have already issued
13836 an error. */
13837 TREE_TYPE (parms) = error_mark_node;
13838 }
13839 }
13840
13841 /* Returns nonzero if T is a local variable. */
13842
13843 int
local_variable_p(const_tree t)13844 local_variable_p (const_tree t)
13845 {
13846 if ((VAR_P (t)
13847 /* A VAR_DECL with a context that is a _TYPE is a static data
13848 member. */
13849 && !TYPE_P (CP_DECL_CONTEXT (t))
13850 /* Any other non-local variable must be at namespace scope. */
13851 && !DECL_NAMESPACE_SCOPE_P (t))
13852 || (TREE_CODE (t) == PARM_DECL))
13853 return 1;
13854
13855 return 0;
13856 }
13857
13858 /* Like local_variable_p, but suitable for use as a tree-walking
13859 function. */
13860
13861 static tree
local_variable_p_walkfn(tree * tp,int * walk_subtrees,void *)13862 local_variable_p_walkfn (tree *tp, int *walk_subtrees,
13863 void * /*data*/)
13864 {
13865 if (local_variable_p (*tp)
13866 && (!DECL_ARTIFICIAL (*tp) || DECL_NAME (*tp) == this_identifier))
13867 return *tp;
13868 else if (TYPE_P (*tp))
13869 *walk_subtrees = 0;
13870
13871 return NULL_TREE;
13872 }
13873
13874 /* Check that ARG, which is a default-argument expression for a
13875 parameter DECL, is valid. Returns ARG, or ERROR_MARK_NODE, if
13876 something goes wrong. DECL may also be a _TYPE node, rather than a
13877 DECL, if there is no DECL available. */
13878
13879 tree
check_default_argument(tree decl,tree arg,tsubst_flags_t complain)13880 check_default_argument (tree decl, tree arg, tsubst_flags_t complain)
13881 {
13882 tree var;
13883 tree decl_type;
13884
13885 if (TREE_CODE (arg) == DEFERRED_PARSE)
13886 /* We get a DEFERRED_PARSE when looking at an in-class declaration
13887 with a default argument. Ignore the argument for now; we'll
13888 deal with it after the class is complete. */
13889 return arg;
13890
13891 if (TYPE_P (decl))
13892 {
13893 decl_type = decl;
13894 decl = NULL_TREE;
13895 }
13896 else
13897 decl_type = TREE_TYPE (decl);
13898
13899 if (arg == error_mark_node
13900 || decl == error_mark_node
13901 || TREE_TYPE (arg) == error_mark_node
13902 || decl_type == error_mark_node)
13903 /* Something already went wrong. There's no need to check
13904 further. */
13905 return error_mark_node;
13906
13907 /* [dcl.fct.default]
13908
13909 A default argument expression is implicitly converted to the
13910 parameter type. */
13911 ++cp_unevaluated_operand;
13912 /* Avoid digest_init clobbering the initializer. */
13913 tree carg = BRACE_ENCLOSED_INITIALIZER_P (arg) ? unshare_expr (arg): arg;
13914 perform_implicit_conversion_flags (decl_type, carg, complain,
13915 LOOKUP_IMPLICIT);
13916 --cp_unevaluated_operand;
13917
13918 /* Avoid redundant -Wzero-as-null-pointer-constant warnings at
13919 the call sites. */
13920 if (TYPE_PTR_OR_PTRMEM_P (decl_type)
13921 && null_ptr_cst_p (arg)
13922 /* Don't lose side-effects as in PR90473. */
13923 && !TREE_SIDE_EFFECTS (arg))
13924 return nullptr_node;
13925
13926 /* [dcl.fct.default]
13927
13928 Local variables shall not be used in default argument
13929 expressions.
13930
13931 The keyword `this' shall not be used in a default argument of a
13932 member function. */
13933 var = cp_walk_tree_without_duplicates (&arg, local_variable_p_walkfn, NULL);
13934 if (var)
13935 {
13936 if (complain & tf_warning_or_error)
13937 {
13938 if (DECL_NAME (var) == this_identifier)
13939 permerror (input_location, "default argument %qE uses %qD",
13940 arg, var);
13941 else
13942 error ("default argument %qE uses local variable %qD", arg, var);
13943 }
13944 return error_mark_node;
13945 }
13946
13947 /* All is well. */
13948 return arg;
13949 }
13950
13951 /* Returns a deprecated type used within TYPE, or NULL_TREE if none. */
13952
13953 static tree
type_is_deprecated(tree type)13954 type_is_deprecated (tree type)
13955 {
13956 enum tree_code code;
13957 if (TREE_DEPRECATED (type))
13958 return type;
13959 if (TYPE_NAME (type))
13960 {
13961 if (TREE_DEPRECATED (TYPE_NAME (type)))
13962 return type;
13963 else
13964 {
13965 cp_warn_deprecated_use_scopes (CP_DECL_CONTEXT (TYPE_NAME (type)));
13966 return NULL_TREE;
13967 }
13968 }
13969
13970 /* Do warn about using typedefs to a deprecated class. */
13971 if (OVERLOAD_TYPE_P (type) && type != TYPE_MAIN_VARIANT (type))
13972 return type_is_deprecated (TYPE_MAIN_VARIANT (type));
13973
13974 code = TREE_CODE (type);
13975
13976 if (code == POINTER_TYPE || code == REFERENCE_TYPE
13977 || code == OFFSET_TYPE || code == FUNCTION_TYPE
13978 || code == METHOD_TYPE || code == ARRAY_TYPE)
13979 return type_is_deprecated (TREE_TYPE (type));
13980
13981 if (TYPE_PTRMEMFUNC_P (type))
13982 return type_is_deprecated
13983 (TREE_TYPE (TREE_TYPE (TYPE_PTRMEMFUNC_FN_TYPE (type))));
13984
13985 return NULL_TREE;
13986 }
13987
13988 /* Decode the list of parameter types for a function type.
13989 Given the list of things declared inside the parens,
13990 return a list of types.
13991
13992 If this parameter does not end with an ellipsis, we append
13993 void_list_node.
13994
13995 *PARMS is set to the chain of PARM_DECLs created. */
13996
13997 tree
grokparms(tree parmlist,tree * parms)13998 grokparms (tree parmlist, tree *parms)
13999 {
14000 tree result = NULL_TREE;
14001 tree decls = NULL_TREE;
14002 tree parm;
14003 int any_error = 0;
14004
14005 for (parm = parmlist; parm != NULL_TREE; parm = TREE_CHAIN (parm))
14006 {
14007 tree type = NULL_TREE;
14008 tree init = TREE_PURPOSE (parm);
14009 tree decl = TREE_VALUE (parm);
14010
14011 if (parm == void_list_node)
14012 break;
14013
14014 if (! decl || TREE_TYPE (decl) == error_mark_node)
14015 continue;
14016
14017 type = TREE_TYPE (decl);
14018 if (VOID_TYPE_P (type))
14019 {
14020 if (same_type_p (type, void_type_node)
14021 && !init
14022 && !DECL_NAME (decl) && !result
14023 && TREE_CHAIN (parm) == void_list_node)
14024 /* DR 577: A parameter list consisting of a single
14025 unnamed parameter of non-dependent type 'void'. */
14026 break;
14027 else if (cv_qualified_p (type))
14028 error_at (DECL_SOURCE_LOCATION (decl),
14029 "invalid use of cv-qualified type %qT in "
14030 "parameter declaration", type);
14031 else
14032 error_at (DECL_SOURCE_LOCATION (decl),
14033 "invalid use of type %<void%> in parameter "
14034 "declaration");
14035 /* It's not a good idea to actually create parameters of
14036 type `void'; other parts of the compiler assume that a
14037 void type terminates the parameter list. */
14038 type = error_mark_node;
14039 TREE_TYPE (decl) = error_mark_node;
14040 }
14041
14042 if (type != error_mark_node)
14043 {
14044 if (deprecated_state != DEPRECATED_SUPPRESS)
14045 {
14046 tree deptype = type_is_deprecated (type);
14047 if (deptype)
14048 cp_warn_deprecated_use (deptype);
14049 }
14050
14051 /* [dcl.fct] "A parameter with volatile-qualified type is
14052 deprecated." */
14053 if (CP_TYPE_VOLATILE_P (type))
14054 warning_at (DECL_SOURCE_LOCATION (decl), OPT_Wvolatile,
14055 "%<volatile%>-qualified parameter is "
14056 "deprecated");
14057
14058 /* Top-level qualifiers on the parameters are
14059 ignored for function types. */
14060 type = cp_build_qualified_type (type, 0);
14061 if (TREE_CODE (type) == METHOD_TYPE)
14062 {
14063 error ("parameter %qD invalidly declared method type", decl);
14064 type = build_pointer_type (type);
14065 TREE_TYPE (decl) = type;
14066 }
14067 else if (abstract_virtuals_error (decl, type))
14068 any_error = 1; /* Seems like a good idea. */
14069 else if (cxx_dialect < cxx17 && INDIRECT_TYPE_P (type))
14070 {
14071 /* Before C++17 DR 393:
14072 [dcl.fct]/6, parameter types cannot contain pointers
14073 (references) to arrays of unknown bound. */
14074 tree t = TREE_TYPE (type);
14075 int ptr = TYPE_PTR_P (type);
14076
14077 while (1)
14078 {
14079 if (TYPE_PTR_P (t))
14080 ptr = 1;
14081 else if (TREE_CODE (t) != ARRAY_TYPE)
14082 break;
14083 else if (!TYPE_DOMAIN (t))
14084 break;
14085 t = TREE_TYPE (t);
14086 }
14087 if (TREE_CODE (t) == ARRAY_TYPE)
14088 pedwarn (DECL_SOURCE_LOCATION (decl), OPT_Wpedantic,
14089 ptr
14090 ? G_("parameter %qD includes pointer to array of "
14091 "unknown bound %qT")
14092 : G_("parameter %qD includes reference to array of "
14093 "unknown bound %qT"),
14094 decl, t);
14095 }
14096
14097 if (any_error)
14098 init = NULL_TREE;
14099 else if (init && !processing_template_decl)
14100 init = check_default_argument (decl, init, tf_warning_or_error);
14101 }
14102
14103 DECL_CHAIN (decl) = decls;
14104 decls = decl;
14105 result = tree_cons (init, type, result);
14106 }
14107 decls = nreverse (decls);
14108 result = nreverse (result);
14109 if (parm)
14110 result = chainon (result, void_list_node);
14111 *parms = decls;
14112
14113 return result;
14114 }
14115
14116
14117 /* D is a constructor or overloaded `operator='.
14118
14119 Let T be the class in which D is declared. Then, this function
14120 returns:
14121
14122 -1 if D's is an ill-formed constructor or copy assignment operator
14123 whose first parameter is of type `T'.
14124 0 if D is not a copy constructor or copy assignment
14125 operator.
14126 1 if D is a copy constructor or copy assignment operator whose
14127 first parameter is a reference to non-const qualified T.
14128 2 if D is a copy constructor or copy assignment operator whose
14129 first parameter is a reference to const qualified T.
14130
14131 This function can be used as a predicate. Positive values indicate
14132 a copy constructor and nonzero values indicate a copy assignment
14133 operator. */
14134
14135 int
copy_fn_p(const_tree d)14136 copy_fn_p (const_tree d)
14137 {
14138 tree args;
14139 tree arg_type;
14140 int result = 1;
14141
14142 gcc_assert (DECL_FUNCTION_MEMBER_P (d));
14143
14144 if (TREE_CODE (d) == TEMPLATE_DECL
14145 || (DECL_TEMPLATE_INFO (d)
14146 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (d))))
14147 /* Instantiations of template member functions are never copy
14148 functions. Note that member functions of templated classes are
14149 represented as template functions internally, and we must
14150 accept those as copy functions. */
14151 return 0;
14152
14153 args = FUNCTION_FIRST_USER_PARMTYPE (d);
14154 if (!args)
14155 return 0;
14156
14157 arg_type = TREE_VALUE (args);
14158 if (arg_type == error_mark_node)
14159 return 0;
14160
14161 if (TYPE_MAIN_VARIANT (arg_type) == DECL_CONTEXT (d))
14162 {
14163 /* Pass by value copy assignment operator. */
14164 result = -1;
14165 }
14166 else if (TYPE_REF_P (arg_type)
14167 && !TYPE_REF_IS_RVALUE (arg_type)
14168 && TYPE_MAIN_VARIANT (TREE_TYPE (arg_type)) == DECL_CONTEXT (d))
14169 {
14170 if (CP_TYPE_CONST_P (TREE_TYPE (arg_type)))
14171 result = 2;
14172 }
14173 else
14174 return 0;
14175
14176 args = TREE_CHAIN (args);
14177
14178 if (args && args != void_list_node && !TREE_PURPOSE (args))
14179 /* There are more non-optional args. */
14180 return 0;
14181
14182 return result;
14183 }
14184
14185 /* D is a constructor or overloaded `operator='.
14186
14187 Let T be the class in which D is declared. Then, this function
14188 returns true when D is a move constructor or move assignment
14189 operator, false otherwise. */
14190
14191 bool
move_fn_p(const_tree d)14192 move_fn_p (const_tree d)
14193 {
14194 gcc_assert (DECL_FUNCTION_MEMBER_P (d));
14195
14196 if (cxx_dialect == cxx98)
14197 /* There are no move constructors if we are in C++98 mode. */
14198 return false;
14199
14200 if (TREE_CODE (d) == TEMPLATE_DECL
14201 || (DECL_TEMPLATE_INFO (d)
14202 && DECL_MEMBER_TEMPLATE_P (DECL_TI_TEMPLATE (d))))
14203 /* Instantiations of template member functions are never move
14204 functions. Note that member functions of templated classes are
14205 represented as template functions internally, and we must
14206 accept those as move functions. */
14207 return 0;
14208
14209 return move_signature_fn_p (d);
14210 }
14211
14212 /* D is a constructor or overloaded `operator='.
14213
14214 Then, this function returns true when D has the same signature as a move
14215 constructor or move assignment operator (because either it is such a
14216 ctor/op= or it is a template specialization with the same signature),
14217 false otherwise. */
14218
14219 bool
move_signature_fn_p(const_tree d)14220 move_signature_fn_p (const_tree d)
14221 {
14222 tree args;
14223 tree arg_type;
14224 bool result = false;
14225
14226 args = FUNCTION_FIRST_USER_PARMTYPE (d);
14227 if (!args)
14228 return 0;
14229
14230 arg_type = TREE_VALUE (args);
14231 if (arg_type == error_mark_node)
14232 return 0;
14233
14234 if (TYPE_REF_P (arg_type)
14235 && TYPE_REF_IS_RVALUE (arg_type)
14236 && same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (arg_type)),
14237 DECL_CONTEXT (d)))
14238 result = true;
14239
14240 args = TREE_CHAIN (args);
14241
14242 if (args && args != void_list_node && !TREE_PURPOSE (args))
14243 /* There are more non-optional args. */
14244 return false;
14245
14246 return result;
14247 }
14248
14249 /* Remember any special properties of member function DECL. */
14250
14251 void
grok_special_member_properties(tree decl)14252 grok_special_member_properties (tree decl)
14253 {
14254 tree class_type;
14255
14256 if (TREE_CODE (decl) == USING_DECL
14257 || !DECL_NONSTATIC_MEMBER_FUNCTION_P (decl))
14258 return;
14259
14260 class_type = DECL_CONTEXT (decl);
14261 if (IDENTIFIER_CTOR_P (DECL_NAME (decl)))
14262 {
14263 int ctor = copy_fn_p (decl);
14264
14265 if (!DECL_ARTIFICIAL (decl))
14266 TYPE_HAS_USER_CONSTRUCTOR (class_type) = 1;
14267
14268 if (ctor > 0)
14269 {
14270 /* [class.copy]
14271
14272 A non-template constructor for class X is a copy
14273 constructor if its first parameter is of type X&, const
14274 X&, volatile X& or const volatile X&, and either there
14275 are no other parameters or else all other parameters have
14276 default arguments. */
14277 TYPE_HAS_COPY_CTOR (class_type) = 1;
14278 if (ctor > 1)
14279 TYPE_HAS_CONST_COPY_CTOR (class_type) = 1;
14280 }
14281 else if (sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (decl)))
14282 TYPE_HAS_DEFAULT_CONSTRUCTOR (class_type) = 1;
14283 else if (is_list_ctor (decl))
14284 TYPE_HAS_LIST_CTOR (class_type) = 1;
14285
14286 if (DECL_DECLARED_CONSTEXPR_P (decl)
14287 && !ctor && !move_fn_p (decl))
14288 TYPE_HAS_CONSTEXPR_CTOR (class_type) = 1;
14289 }
14290 else if (DECL_NAME (decl) == assign_op_identifier)
14291 {
14292 /* [class.copy]
14293
14294 A non-template assignment operator for class X is a copy
14295 assignment operator if its parameter is of type X, X&, const
14296 X&, volatile X& or const volatile X&. */
14297
14298 int assop = copy_fn_p (decl);
14299
14300 if (assop)
14301 {
14302 TYPE_HAS_COPY_ASSIGN (class_type) = 1;
14303 if (assop != 1)
14304 TYPE_HAS_CONST_COPY_ASSIGN (class_type) = 1;
14305 }
14306 }
14307 else if (IDENTIFIER_CONV_OP_P (DECL_NAME (decl)))
14308 TYPE_HAS_CONVERSION (class_type) = true;
14309
14310 /* Destructors are handled in check_methods. */
14311 }
14312
14313 /* Check a constructor DECL has the correct form. Complains
14314 if the class has a constructor of the form X(X). */
14315
14316 bool
grok_ctor_properties(const_tree ctype,const_tree decl)14317 grok_ctor_properties (const_tree ctype, const_tree decl)
14318 {
14319 int ctor_parm = copy_fn_p (decl);
14320
14321 if (ctor_parm < 0)
14322 {
14323 /* [class.copy]
14324
14325 A declaration of a constructor for a class X is ill-formed if
14326 its first parameter is of type (optionally cv-qualified) X
14327 and either there are no other parameters or else all other
14328 parameters have default arguments.
14329
14330 We *don't* complain about member template instantiations that
14331 have this form, though; they can occur as we try to decide
14332 what constructor to use during overload resolution. Since
14333 overload resolution will never prefer such a constructor to
14334 the non-template copy constructor (which is either explicitly
14335 or implicitly defined), there's no need to worry about their
14336 existence. Theoretically, they should never even be
14337 instantiated, but that's hard to forestall. */
14338 error_at (DECL_SOURCE_LOCATION (decl),
14339 "invalid constructor; you probably meant %<%T (const %T&)%>",
14340 ctype, ctype);
14341 return false;
14342 }
14343
14344 return true;
14345 }
14346
14347 /* DECL is a declaration for an overloaded or conversion operator. If
14348 COMPLAIN is true, errors are issued for invalid declarations. */
14349
14350 bool
grok_op_properties(tree decl,bool complain)14351 grok_op_properties (tree decl, bool complain)
14352 {
14353 tree argtypes = TYPE_ARG_TYPES (TREE_TYPE (decl));
14354 bool methodp = TREE_CODE (TREE_TYPE (decl)) == METHOD_TYPE;
14355 tree name = DECL_NAME (decl);
14356 location_t loc = DECL_SOURCE_LOCATION (decl);
14357
14358 tree class_type = DECL_CONTEXT (decl);
14359 if (class_type && !CLASS_TYPE_P (class_type))
14360 class_type = NULL_TREE;
14361
14362 tree_code operator_code;
14363 unsigned op_flags;
14364 if (IDENTIFIER_CONV_OP_P (name))
14365 {
14366 /* Conversion operators are TYPE_EXPR for the purposes of this
14367 function. */
14368 operator_code = TYPE_EXPR;
14369 op_flags = OVL_OP_FLAG_UNARY;
14370 }
14371 else
14372 {
14373 const ovl_op_info_t *ovl_op = IDENTIFIER_OVL_OP_INFO (name);
14374
14375 operator_code = ovl_op->tree_code;
14376 op_flags = ovl_op->flags;
14377 gcc_checking_assert (operator_code != ERROR_MARK);
14378 DECL_OVERLOADED_OPERATOR_CODE_RAW (decl) = ovl_op->ovl_op_code;
14379 }
14380
14381 if (op_flags & OVL_OP_FLAG_ALLOC)
14382 {
14383 /* operator new and operator delete are quite special. */
14384 if (class_type)
14385 switch (op_flags)
14386 {
14387 case OVL_OP_FLAG_ALLOC:
14388 TYPE_HAS_NEW_OPERATOR (class_type) = 1;
14389 break;
14390
14391 case OVL_OP_FLAG_ALLOC | OVL_OP_FLAG_DELETE:
14392 TYPE_GETS_DELETE (class_type) |= 1;
14393 break;
14394
14395 case OVL_OP_FLAG_ALLOC | OVL_OP_FLAG_VEC:
14396 TYPE_HAS_ARRAY_NEW_OPERATOR (class_type) = 1;
14397 break;
14398
14399 case OVL_OP_FLAG_ALLOC | OVL_OP_FLAG_DELETE | OVL_OP_FLAG_VEC:
14400 TYPE_GETS_DELETE (class_type) |= 2;
14401 break;
14402
14403 default:
14404 gcc_unreachable ();
14405 }
14406
14407 /* [basic.std.dynamic.allocation]/1:
14408
14409 A program is ill-formed if an allocation function is declared
14410 in a namespace scope other than global scope or declared
14411 static in global scope.
14412
14413 The same also holds true for deallocation functions. */
14414 if (DECL_NAMESPACE_SCOPE_P (decl))
14415 {
14416 if (CP_DECL_CONTEXT (decl) != global_namespace)
14417 {
14418 error_at (loc, "%qD may not be declared within a namespace",
14419 decl);
14420 return false;
14421 }
14422
14423 if (!TREE_PUBLIC (decl))
14424 {
14425 error_at (loc, "%qD may not be declared as static", decl);
14426 return false;
14427 }
14428 }
14429
14430 if (op_flags & OVL_OP_FLAG_DELETE)
14431 {
14432 DECL_SET_IS_OPERATOR_DELETE (decl, true);
14433 coerce_delete_type (decl, loc);
14434 }
14435 else
14436 {
14437 DECL_SET_IS_OPERATOR_NEW (decl, true);
14438 TREE_TYPE (decl) = coerce_new_type (TREE_TYPE (decl), loc);
14439 }
14440
14441 return true;
14442 }
14443
14444 /* An operator function must either be a non-static member function
14445 or have at least one parameter of a class, a reference to a class,
14446 an enumeration, or a reference to an enumeration. 13.4.0.6 */
14447 if (! methodp || DECL_STATIC_FUNCTION_P (decl))
14448 {
14449 if (operator_code == TYPE_EXPR
14450 || operator_code == CALL_EXPR
14451 || operator_code == COMPONENT_REF
14452 || operator_code == ARRAY_REF
14453 || operator_code == NOP_EXPR)
14454 {
14455 error_at (loc, "%qD must be a nonstatic member function", decl);
14456 return false;
14457 }
14458
14459 if (DECL_STATIC_FUNCTION_P (decl))
14460 {
14461 error_at (loc, "%qD must be either a non-static member "
14462 "function or a non-member function", decl);
14463 return false;
14464 }
14465
14466 for (tree arg = argtypes; ; arg = TREE_CHAIN (arg))
14467 {
14468 if (!arg || arg == void_list_node)
14469 {
14470 if (complain)
14471 error_at(loc, "%qD must have an argument of class or "
14472 "enumerated type", decl);
14473 return false;
14474 }
14475
14476 tree type = non_reference (TREE_VALUE (arg));
14477 if (type == error_mark_node)
14478 return false;
14479
14480 /* MAYBE_CLASS_TYPE_P, rather than CLASS_TYPE_P, is used
14481 because these checks are performed even on template
14482 functions. */
14483 if (MAYBE_CLASS_TYPE_P (type)
14484 || TREE_CODE (type) == ENUMERAL_TYPE)
14485 break;
14486 }
14487 }
14488
14489 if (operator_code == CALL_EXPR)
14490 /* There are no further restrictions on the arguments to an overloaded
14491 "operator ()". */
14492 return true;
14493
14494 if (operator_code == COND_EXPR)
14495 {
14496 /* 13.4.0.3 */
14497 error_at (loc, "ISO C++ prohibits overloading %<operator ?:%>");
14498 return false;
14499 }
14500
14501 /* Count the number of arguments and check for ellipsis. */
14502 int arity = 0;
14503 for (tree arg = argtypes; arg != void_list_node; arg = TREE_CHAIN (arg))
14504 {
14505 if (!arg)
14506 {
14507 /* Variadic. */
14508 error_at (loc, "%qD must not have variable number of arguments",
14509 decl);
14510 return false;
14511 }
14512 ++arity;
14513 }
14514
14515 /* Verify correct number of arguments. */
14516 switch (op_flags)
14517 {
14518 case OVL_OP_FLAG_AMBIARY:
14519 if (arity == 1)
14520 {
14521 /* We have a unary instance of an ambi-ary op. Remap to the
14522 unary one. */
14523 unsigned alt = ovl_op_alternate[ovl_op_mapping [operator_code]];
14524 const ovl_op_info_t *ovl_op = &ovl_op_info[false][alt];
14525 gcc_checking_assert (ovl_op->flags == OVL_OP_FLAG_UNARY);
14526 operator_code = ovl_op->tree_code;
14527 DECL_OVERLOADED_OPERATOR_CODE_RAW (decl) = ovl_op->ovl_op_code;
14528 }
14529 else if (arity != 2)
14530 {
14531 /* This was an ambiguous operator but is invalid. */
14532 error_at (loc,
14533 methodp
14534 ? G_("%qD must have either zero or one argument")
14535 : G_("%qD must have either one or two arguments"), decl);
14536 return false;
14537 }
14538 else if ((operator_code == POSTINCREMENT_EXPR
14539 || operator_code == POSTDECREMENT_EXPR)
14540 && ! processing_template_decl
14541 /* x++ and x--'s second argument must be an int. */
14542 && ! same_type_p (TREE_VALUE (TREE_CHAIN (argtypes)),
14543 integer_type_node))
14544 {
14545 error_at (loc,
14546 methodp
14547 ? G_("postfix %qD must have %<int%> as its argument")
14548 : G_("postfix %qD must have %<int%> as its second argument"),
14549 decl);
14550 return false;
14551 }
14552 break;
14553
14554 case OVL_OP_FLAG_UNARY:
14555 if (arity != 1)
14556 {
14557 error_at (loc,
14558 methodp
14559 ? G_("%qD must have no arguments")
14560 : G_("%qD must have exactly one argument"), decl);
14561 return false;
14562 }
14563 break;
14564
14565 case OVL_OP_FLAG_BINARY:
14566 if (arity != 2)
14567 {
14568 error_at (loc,
14569 methodp
14570 ? G_("%qD must have exactly one argument")
14571 : G_("%qD must have exactly two arguments"), decl);
14572 return false;
14573 }
14574 break;
14575
14576 default:
14577 gcc_unreachable ();
14578 }
14579
14580 /* There can be no default arguments. */
14581 for (tree arg = argtypes; arg != void_list_node; arg = TREE_CHAIN (arg))
14582 if (TREE_PURPOSE (arg))
14583 {
14584 TREE_PURPOSE (arg) = NULL_TREE;
14585 error_at (loc, "%qD cannot have default arguments", decl);
14586 return false;
14587 }
14588
14589 /* At this point the declaration is well-formed. It may not be
14590 sensible though. */
14591
14592 /* Check member function warnings only on the in-class declaration.
14593 There's no point warning on an out-of-class definition. */
14594 if (class_type && class_type != current_class_type)
14595 return true;
14596
14597 /* Warn about conversion operators that will never be used. */
14598 if (IDENTIFIER_CONV_OP_P (name)
14599 && ! DECL_TEMPLATE_INFO (decl)
14600 && warn_class_conversion)
14601 {
14602 tree t = TREE_TYPE (name);
14603 int ref = TYPE_REF_P (t);
14604
14605 if (ref)
14606 t = TYPE_MAIN_VARIANT (TREE_TYPE (t));
14607
14608 if (VOID_TYPE_P (t))
14609 warning_at (loc, OPT_Wclass_conversion, "converting %qT to %<void%> "
14610 "will never use a type conversion operator", class_type);
14611 else if (class_type)
14612 {
14613 if (same_type_ignoring_top_level_qualifiers_p (t, class_type))
14614 warning_at (loc, OPT_Wclass_conversion,
14615 ref
14616 ? G_("converting %qT to a reference to the same type "
14617 "will never use a type conversion operator")
14618 : G_("converting %qT to the same type "
14619 "will never use a type conversion operator"),
14620 class_type);
14621 /* Don't force t to be complete here. */
14622 else if (MAYBE_CLASS_TYPE_P (t)
14623 && COMPLETE_TYPE_P (t)
14624 && DERIVED_FROM_P (t, class_type))
14625 warning_at (loc, OPT_Wclass_conversion,
14626 ref
14627 ? G_("converting %qT to a reference to a base class "
14628 "%qT will never use a type conversion operator")
14629 : G_("converting %qT to a base class %qT "
14630 "will never use a type conversion operator"),
14631 class_type, t);
14632 }
14633 }
14634
14635 if (!warn_ecpp)
14636 return true;
14637
14638 /* Effective C++ rules below. */
14639
14640 /* More Effective C++ rule 7. */
14641 if (operator_code == TRUTH_ANDIF_EXPR
14642 || operator_code == TRUTH_ORIF_EXPR
14643 || operator_code == COMPOUND_EXPR)
14644 warning_at (loc, OPT_Weffc__,
14645 "user-defined %qD always evaluates both arguments", decl);
14646
14647 /* More Effective C++ rule 6. */
14648 if (operator_code == POSTINCREMENT_EXPR
14649 || operator_code == POSTDECREMENT_EXPR
14650 || operator_code == PREINCREMENT_EXPR
14651 || operator_code == PREDECREMENT_EXPR)
14652 {
14653 tree arg = TREE_VALUE (argtypes);
14654 tree ret = TREE_TYPE (TREE_TYPE (decl));
14655 if (methodp || TYPE_REF_P (arg))
14656 arg = TREE_TYPE (arg);
14657 arg = TYPE_MAIN_VARIANT (arg);
14658
14659 if (operator_code == PREINCREMENT_EXPR
14660 || operator_code == PREDECREMENT_EXPR)
14661 {
14662 if (!TYPE_REF_P (ret)
14663 || !same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (ret)), arg))
14664 warning_at (loc, OPT_Weffc__, "prefix %qD should return %qT", decl,
14665 build_reference_type (arg));
14666 }
14667 else
14668 {
14669 if (!same_type_p (TYPE_MAIN_VARIANT (ret), arg))
14670 warning_at (loc, OPT_Weffc__,
14671 "postfix %qD should return %qT", decl, arg);
14672 }
14673 }
14674
14675 /* Effective C++ rule 23. */
14676 if (!DECL_ASSIGNMENT_OPERATOR_P (decl)
14677 && (operator_code == PLUS_EXPR
14678 || operator_code == MINUS_EXPR
14679 || operator_code == TRUNC_DIV_EXPR
14680 || operator_code == MULT_EXPR
14681 || operator_code == TRUNC_MOD_EXPR)
14682 && TYPE_REF_P (TREE_TYPE (TREE_TYPE (decl))))
14683 warning_at (loc, OPT_Weffc__, "%qD should return by value", decl);
14684
14685 return true;
14686 }
14687
14688 /* Return a string giving the keyword associate with CODE. */
14689
14690 static const char *
tag_name(enum tag_types code)14691 tag_name (enum tag_types code)
14692 {
14693 switch (code)
14694 {
14695 case record_type:
14696 return "struct";
14697 case class_type:
14698 return "class";
14699 case union_type:
14700 return "union";
14701 case enum_type:
14702 return "enum";
14703 case typename_type:
14704 return "typename";
14705 default:
14706 gcc_unreachable ();
14707 }
14708 }
14709
14710 /* Name lookup in an elaborated-type-specifier (after the keyword
14711 indicated by TAG_CODE) has found the TYPE_DECL DECL. If the
14712 elaborated-type-specifier is invalid, issue a diagnostic and return
14713 error_mark_node; otherwise, return the *_TYPE to which it referred.
14714 If ALLOW_TEMPLATE_P is true, TYPE may be a class template. */
14715
14716 tree
check_elaborated_type_specifier(enum tag_types tag_code,tree decl,bool allow_template_p)14717 check_elaborated_type_specifier (enum tag_types tag_code,
14718 tree decl,
14719 bool allow_template_p)
14720 {
14721 tree type;
14722
14723 /* In the case of:
14724
14725 struct S { struct S *p; };
14726
14727 name lookup will find the TYPE_DECL for the implicit "S::S"
14728 typedef. Adjust for that here. */
14729 if (DECL_SELF_REFERENCE_P (decl))
14730 decl = TYPE_NAME (TREE_TYPE (decl));
14731
14732 type = TREE_TYPE (decl);
14733
14734 /* Check TEMPLATE_TYPE_PARM first because DECL_IMPLICIT_TYPEDEF_P
14735 is false for this case as well. */
14736 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM)
14737 {
14738 error ("using template type parameter %qT after %qs",
14739 type, tag_name (tag_code));
14740 return error_mark_node;
14741 }
14742 /* Accept template template parameters. */
14743 else if (allow_template_p
14744 && (TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM
14745 || TREE_CODE (type) == TEMPLATE_TEMPLATE_PARM))
14746 ;
14747 /* [dcl.type.elab]
14748
14749 If the identifier resolves to a typedef-name or the
14750 simple-template-id resolves to an alias template
14751 specialization, the elaborated-type-specifier is ill-formed.
14752
14753 In other words, the only legitimate declaration to use in the
14754 elaborated type specifier is the implicit typedef created when
14755 the type is declared. */
14756 else if (!DECL_IMPLICIT_TYPEDEF_P (decl)
14757 && !DECL_SELF_REFERENCE_P (decl)
14758 && tag_code != typename_type)
14759 {
14760 if (alias_template_specialization_p (type, nt_opaque))
14761 error ("using alias template specialization %qT after %qs",
14762 type, tag_name (tag_code));
14763 else
14764 error ("using typedef-name %qD after %qs", decl, tag_name (tag_code));
14765 inform (DECL_SOURCE_LOCATION (decl),
14766 "%qD has a previous declaration here", decl);
14767 return error_mark_node;
14768 }
14769 else if (TREE_CODE (type) != RECORD_TYPE
14770 && TREE_CODE (type) != UNION_TYPE
14771 && tag_code != enum_type
14772 && tag_code != typename_type)
14773 {
14774 error ("%qT referred to as %qs", type, tag_name (tag_code));
14775 inform (location_of (type), "%qT has a previous declaration here", type);
14776 return error_mark_node;
14777 }
14778 else if (TREE_CODE (type) != ENUMERAL_TYPE
14779 && tag_code == enum_type)
14780 {
14781 error ("%qT referred to as enum", type);
14782 inform (location_of (type), "%qT has a previous declaration here", type);
14783 return error_mark_node;
14784 }
14785 else if (!allow_template_p
14786 && TREE_CODE (type) == RECORD_TYPE
14787 && CLASSTYPE_IS_TEMPLATE (type))
14788 {
14789 /* If a class template appears as elaborated type specifier
14790 without a template header such as:
14791
14792 template <class T> class C {};
14793 void f(class C); // No template header here
14794
14795 then the required template argument is missing. */
14796 error ("template argument required for %<%s %T%>",
14797 tag_name (tag_code),
14798 DECL_NAME (CLASSTYPE_TI_TEMPLATE (type)));
14799 return error_mark_node;
14800 }
14801
14802 return type;
14803 }
14804
14805 /* Lookup NAME in elaborate type specifier in scope according to
14806 SCOPE and issue diagnostics if necessary.
14807 Return *_TYPE node upon success, NULL_TREE when the NAME is not
14808 found, and ERROR_MARK_NODE for type error. */
14809
14810 static tree
lookup_and_check_tag(enum tag_types tag_code,tree name,tag_scope scope,bool template_header_p)14811 lookup_and_check_tag (enum tag_types tag_code, tree name,
14812 tag_scope scope, bool template_header_p)
14813 {
14814 tree t;
14815 tree decl;
14816 if (scope == ts_global)
14817 {
14818 /* First try ordinary name lookup, ignoring hidden class name
14819 injected via friend declaration. */
14820 decl = lookup_name_prefer_type (name, 2);
14821 decl = strip_using_decl (decl);
14822 /* If that fails, the name will be placed in the smallest
14823 non-class, non-function-prototype scope according to 3.3.1/5.
14824 We may already have a hidden name declared as friend in this
14825 scope. So lookup again but not ignoring hidden names.
14826 If we find one, that name will be made visible rather than
14827 creating a new tag. */
14828 if (!decl)
14829 decl = lookup_type_scope (name, ts_within_enclosing_non_class);
14830 }
14831 else
14832 decl = lookup_type_scope (name, scope);
14833
14834 if (decl
14835 && (DECL_CLASS_TEMPLATE_P (decl)
14836 /* If scope is ts_current we're defining a class, so ignore a
14837 template template parameter. */
14838 || (scope != ts_current
14839 && DECL_TEMPLATE_TEMPLATE_PARM_P (decl))))
14840 decl = DECL_TEMPLATE_RESULT (decl);
14841
14842 if (decl && TREE_CODE (decl) == TYPE_DECL)
14843 {
14844 /* Look for invalid nested type:
14845 class C {
14846 class C {};
14847 }; */
14848 if (scope == ts_current && DECL_SELF_REFERENCE_P (decl))
14849 {
14850 error ("%qD has the same name as the class in which it is "
14851 "declared",
14852 decl);
14853 return error_mark_node;
14854 }
14855
14856 /* Two cases we need to consider when deciding if a class
14857 template is allowed as an elaborated type specifier:
14858 1. It is a self reference to its own class.
14859 2. It comes with a template header.
14860
14861 For example:
14862
14863 template <class T> class C {
14864 class C *c1; // DECL_SELF_REFERENCE_P is true
14865 class D;
14866 };
14867 template <class U> class C; // template_header_p is true
14868 template <class T> class C<T>::D {
14869 class C *c2; // DECL_SELF_REFERENCE_P is true
14870 }; */
14871
14872 t = check_elaborated_type_specifier (tag_code,
14873 decl,
14874 template_header_p
14875 | DECL_SELF_REFERENCE_P (decl));
14876 if (template_header_p && t && CLASS_TYPE_P (t)
14877 && (!CLASSTYPE_TEMPLATE_INFO (t)
14878 || (!PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (t)))))
14879 {
14880 error ("%qT is not a template", t);
14881 inform (location_of (t), "previous declaration here");
14882 if (TYPE_CLASS_SCOPE_P (t)
14883 && CLASSTYPE_TEMPLATE_INFO (TYPE_CONTEXT (t)))
14884 inform (input_location,
14885 "perhaps you want to explicitly add %<%T::%>",
14886 TYPE_CONTEXT (t));
14887 t = error_mark_node;
14888 }
14889
14890 return t;
14891 }
14892 else if (decl && TREE_CODE (decl) == TREE_LIST)
14893 {
14894 error ("reference to %qD is ambiguous", name);
14895 print_candidates (decl);
14896 return error_mark_node;
14897 }
14898 else
14899 return NULL_TREE;
14900 }
14901
14902 /* Get the struct, enum or union (TAG_CODE says which) with tag NAME.
14903 Define the tag as a forward-reference if it is not defined.
14904
14905 If a declaration is given, process it here, and report an error if
14906 multiple declarations are not identical.
14907
14908 SCOPE is TS_CURRENT when this is also a definition. Only look in
14909 the current frame for the name (since C++ allows new names in any
14910 scope.) It is TS_WITHIN_ENCLOSING_NON_CLASS if this is a friend
14911 declaration. Only look beginning from the current scope outward up
14912 till the nearest non-class scope. Otherwise it is TS_GLOBAL.
14913
14914 TEMPLATE_HEADER_P is true when this declaration is preceded by
14915 a set of template parameters. */
14916
14917 static tree
xref_tag_1(enum tag_types tag_code,tree name,tag_scope scope,bool template_header_p)14918 xref_tag_1 (enum tag_types tag_code, tree name,
14919 tag_scope scope, bool template_header_p)
14920 {
14921 enum tree_code code;
14922 tree context = NULL_TREE;
14923
14924 gcc_assert (identifier_p (name));
14925
14926 switch (tag_code)
14927 {
14928 case record_type:
14929 case class_type:
14930 code = RECORD_TYPE;
14931 break;
14932 case union_type:
14933 code = UNION_TYPE;
14934 break;
14935 case enum_type:
14936 code = ENUMERAL_TYPE;
14937 break;
14938 default:
14939 gcc_unreachable ();
14940 }
14941
14942 /* In case of anonymous name, xref_tag is only called to
14943 make type node and push name. Name lookup is not required. */
14944 tree t = NULL_TREE;
14945 if (scope != ts_lambda && !IDENTIFIER_ANON_P (name))
14946 t = lookup_and_check_tag (tag_code, name, scope, template_header_p);
14947
14948 if (t == error_mark_node)
14949 return error_mark_node;
14950
14951 if (scope != ts_current && t && current_class_type
14952 && template_class_depth (current_class_type)
14953 && template_header_p)
14954 {
14955 if (TREE_CODE (t) == TEMPLATE_TEMPLATE_PARM)
14956 return t;
14957
14958 /* Since SCOPE is not TS_CURRENT, we are not looking at a
14959 definition of this tag. Since, in addition, we are currently
14960 processing a (member) template declaration of a template
14961 class, we must be very careful; consider:
14962
14963 template <class X> struct S1
14964
14965 template <class U> struct S2
14966 {
14967 template <class V> friend struct S1;
14968 };
14969
14970 Here, the S2::S1 declaration should not be confused with the
14971 outer declaration. In particular, the inner version should
14972 have a template parameter of level 2, not level 1.
14973
14974 On the other hand, when presented with:
14975
14976 template <class T> struct S1
14977 {
14978 template <class U> struct S2 {};
14979 template <class U> friend struct S2;
14980 };
14981
14982 the friend must find S1::S2 eventually. We accomplish this
14983 by making sure that the new type we create to represent this
14984 declaration has the right TYPE_CONTEXT. */
14985 context = TYPE_CONTEXT (t);
14986 t = NULL_TREE;
14987 }
14988
14989 if (! t)
14990 {
14991 /* If no such tag is yet defined, create a forward-reference node
14992 and record it as the "definition".
14993 When a real declaration of this type is found,
14994 the forward-reference will be altered into a real type. */
14995 if (code == ENUMERAL_TYPE)
14996 {
14997 error ("use of enum %q#D without previous declaration", name);
14998 return error_mark_node;
14999 }
15000 else
15001 {
15002 t = make_class_type (code);
15003 TYPE_CONTEXT (t) = context;
15004 if (scope == ts_lambda)
15005 {
15006 /* Mark it as a lambda type. */
15007 CLASSTYPE_LAMBDA_EXPR (t) = error_mark_node;
15008 /* And push it into current scope. */
15009 scope = ts_current;
15010 }
15011 t = pushtag (name, t, scope);
15012 }
15013 }
15014 else
15015 {
15016 if (template_header_p && MAYBE_CLASS_TYPE_P (t))
15017 {
15018 /* Check that we aren't trying to overload a class with different
15019 constraints. */
15020 tree constr = NULL_TREE;
15021 if (current_template_parms)
15022 {
15023 tree reqs = TEMPLATE_PARMS_CONSTRAINTS (current_template_parms);
15024 constr = build_constraints (reqs, NULL_TREE);
15025 }
15026 if (!redeclare_class_template (t, current_template_parms, constr))
15027 return error_mark_node;
15028 }
15029 else if (!processing_template_decl
15030 && CLASS_TYPE_P (t)
15031 && CLASSTYPE_IS_TEMPLATE (t))
15032 {
15033 error ("redeclaration of %qT as a non-template", t);
15034 inform (location_of (t), "previous declaration %qD", t);
15035 return error_mark_node;
15036 }
15037
15038 if (scope != ts_within_enclosing_non_class && TYPE_HIDDEN_P (t))
15039 {
15040 /* This is no longer an invisible friend. Make it
15041 visible. */
15042 tree decl = TYPE_NAME (t);
15043
15044 DECL_ANTICIPATED (decl) = false;
15045 DECL_FRIEND_P (decl) = false;
15046
15047 if (TYPE_TEMPLATE_INFO (t))
15048 {
15049 tree tmpl = TYPE_TI_TEMPLATE (t);
15050 DECL_ANTICIPATED (tmpl) = false;
15051 DECL_FRIEND_P (tmpl) = false;
15052 }
15053 }
15054 }
15055
15056 return t;
15057 }
15058
15059 /* Wrapper for xref_tag_1. */
15060
15061 tree
xref_tag(enum tag_types tag_code,tree name,tag_scope scope,bool template_header_p)15062 xref_tag (enum tag_types tag_code, tree name,
15063 tag_scope scope, bool template_header_p)
15064 {
15065 tree ret;
15066 bool subtime;
15067 subtime = timevar_cond_start (TV_NAME_LOOKUP);
15068 ret = xref_tag_1 (tag_code, name, scope, template_header_p);
15069 timevar_cond_stop (TV_NAME_LOOKUP, subtime);
15070 return ret;
15071 }
15072
15073
15074 tree
xref_tag_from_type(tree old,tree id,tag_scope scope)15075 xref_tag_from_type (tree old, tree id, tag_scope scope)
15076 {
15077 enum tag_types tag_kind;
15078
15079 if (TREE_CODE (old) == RECORD_TYPE)
15080 tag_kind = (CLASSTYPE_DECLARED_CLASS (old) ? class_type : record_type);
15081 else
15082 tag_kind = union_type;
15083
15084 if (id == NULL_TREE)
15085 id = TYPE_IDENTIFIER (old);
15086
15087 return xref_tag (tag_kind, id, scope, false);
15088 }
15089
15090 /* Create the binfo hierarchy for REF with (possibly NULL) base list
15091 BASE_LIST. For each element on BASE_LIST the TREE_PURPOSE is an
15092 access_* node, and the TREE_VALUE is the type of the base-class.
15093 Non-NULL TREE_TYPE indicates virtual inheritance. */
15094
15095 void
xref_basetypes(tree ref,tree base_list)15096 xref_basetypes (tree ref, tree base_list)
15097 {
15098 tree *basep;
15099 tree binfo, base_binfo;
15100 unsigned max_vbases = 0; /* Maximum direct & indirect virtual bases. */
15101 unsigned max_bases = 0; /* Maximum direct bases. */
15102 unsigned max_dvbases = 0; /* Maximum direct virtual bases. */
15103 int i;
15104 tree default_access;
15105 tree igo_prev; /* Track Inheritance Graph Order. */
15106
15107 if (ref == error_mark_node)
15108 return;
15109
15110 /* The base of a derived class is private by default, all others are
15111 public. */
15112 default_access = (TREE_CODE (ref) == RECORD_TYPE
15113 && CLASSTYPE_DECLARED_CLASS (ref)
15114 ? access_private_node : access_public_node);
15115
15116 /* First, make sure that any templates in base-classes are
15117 instantiated. This ensures that if we call ourselves recursively
15118 we do not get confused about which classes are marked and which
15119 are not. */
15120 basep = &base_list;
15121 while (*basep)
15122 {
15123 tree basetype = TREE_VALUE (*basep);
15124
15125 /* The dependent_type_p call below should really be dependent_scope_p
15126 so that we give a hard error about using an incomplete type as a
15127 base, but we allow it with a pedwarn for backward
15128 compatibility. */
15129 if (processing_template_decl
15130 && CLASS_TYPE_P (basetype) && TYPE_BEING_DEFINED (basetype))
15131 cxx_incomplete_type_diagnostic (NULL_TREE, basetype, DK_PEDWARN);
15132 if (!dependent_type_p (basetype)
15133 && !complete_type_or_else (basetype, NULL))
15134 /* An incomplete type. Remove it from the list. */
15135 *basep = TREE_CHAIN (*basep);
15136 else
15137 {
15138 max_bases++;
15139 if (TREE_TYPE (*basep))
15140 max_dvbases++;
15141 if (CLASS_TYPE_P (basetype))
15142 max_vbases += vec_safe_length (CLASSTYPE_VBASECLASSES (basetype));
15143 basep = &TREE_CHAIN (*basep);
15144 }
15145 }
15146 max_vbases += max_dvbases;
15147
15148 TYPE_MARKED_P (ref) = 1;
15149
15150 /* The binfo slot should be empty, unless this is an (ill-formed)
15151 redefinition. */
15152 gcc_assert (!TYPE_BINFO (ref) || TYPE_SIZE (ref));
15153
15154 gcc_assert (TYPE_MAIN_VARIANT (ref) == ref);
15155
15156 binfo = make_tree_binfo (max_bases);
15157
15158 TYPE_BINFO (ref) = binfo;
15159 BINFO_OFFSET (binfo) = size_zero_node;
15160 BINFO_TYPE (binfo) = ref;
15161
15162 /* Apply base-class info set up to the variants of this type. */
15163 fixup_type_variants (ref);
15164
15165 if (max_bases)
15166 {
15167 vec_alloc (BINFO_BASE_ACCESSES (binfo), max_bases);
15168 /* A C++98 POD cannot have base classes. */
15169 CLASSTYPE_NON_LAYOUT_POD_P (ref) = true;
15170
15171 if (TREE_CODE (ref) == UNION_TYPE)
15172 {
15173 error ("derived union %qT invalid", ref);
15174 return;
15175 }
15176 }
15177
15178 if (max_bases > 1)
15179 warning (OPT_Wmultiple_inheritance,
15180 "%qT defined with multiple direct bases", ref);
15181
15182 if (max_vbases)
15183 {
15184 /* An aggregate can't have virtual base classes. */
15185 CLASSTYPE_NON_AGGREGATE (ref) = true;
15186
15187 vec_alloc (CLASSTYPE_VBASECLASSES (ref), max_vbases);
15188
15189 if (max_dvbases)
15190 warning (OPT_Wvirtual_inheritance,
15191 "%qT defined with direct virtual base", ref);
15192 }
15193
15194 for (igo_prev = binfo; base_list; base_list = TREE_CHAIN (base_list))
15195 {
15196 tree access = TREE_PURPOSE (base_list);
15197 int via_virtual = TREE_TYPE (base_list) != NULL_TREE;
15198 tree basetype = TREE_VALUE (base_list);
15199
15200 if (access == access_default_node)
15201 access = default_access;
15202
15203 /* Before C++17, an aggregate cannot have base classes. In C++17, an
15204 aggregate can't have virtual, private, or protected base classes. */
15205 if (cxx_dialect < cxx17
15206 || access != access_public_node
15207 || via_virtual)
15208 CLASSTYPE_NON_AGGREGATE (ref) = true;
15209
15210 if (PACK_EXPANSION_P (basetype))
15211 basetype = PACK_EXPANSION_PATTERN (basetype);
15212 if (TREE_CODE (basetype) == TYPE_DECL)
15213 basetype = TREE_TYPE (basetype);
15214 if (!MAYBE_CLASS_TYPE_P (basetype) || TREE_CODE (basetype) == UNION_TYPE)
15215 {
15216 error ("base type %qT fails to be a struct or class type",
15217 basetype);
15218 goto dropped_base;
15219 }
15220
15221 base_binfo = NULL_TREE;
15222 if (CLASS_TYPE_P (basetype) && !dependent_scope_p (basetype))
15223 {
15224 base_binfo = TYPE_BINFO (basetype);
15225 /* The original basetype could have been a typedef'd type. */
15226 basetype = BINFO_TYPE (base_binfo);
15227
15228 /* Inherit flags from the base. */
15229 TYPE_HAS_NEW_OPERATOR (ref)
15230 |= TYPE_HAS_NEW_OPERATOR (basetype);
15231 TYPE_HAS_ARRAY_NEW_OPERATOR (ref)
15232 |= TYPE_HAS_ARRAY_NEW_OPERATOR (basetype);
15233 TYPE_GETS_DELETE (ref) |= TYPE_GETS_DELETE (basetype);
15234 TYPE_HAS_CONVERSION (ref) |= TYPE_HAS_CONVERSION (basetype);
15235 CLASSTYPE_DIAMOND_SHAPED_P (ref)
15236 |= CLASSTYPE_DIAMOND_SHAPED_P (basetype);
15237 CLASSTYPE_REPEATED_BASE_P (ref)
15238 |= CLASSTYPE_REPEATED_BASE_P (basetype);
15239 }
15240
15241 /* We must do this test after we've seen through a typedef
15242 type. */
15243 if (TYPE_MARKED_P (basetype))
15244 {
15245 if (basetype == ref)
15246 error ("recursive type %qT undefined", basetype);
15247 else
15248 error ("duplicate base type %qT invalid", basetype);
15249 goto dropped_base;
15250 }
15251
15252 if (PACK_EXPANSION_P (TREE_VALUE (base_list)))
15253 /* Regenerate the pack expansion for the bases. */
15254 basetype = make_pack_expansion (basetype);
15255
15256 TYPE_MARKED_P (basetype) = 1;
15257
15258 base_binfo = copy_binfo (base_binfo, basetype, ref,
15259 &igo_prev, via_virtual);
15260 if (!BINFO_INHERITANCE_CHAIN (base_binfo))
15261 BINFO_INHERITANCE_CHAIN (base_binfo) = binfo;
15262
15263 BINFO_BASE_APPEND (binfo, base_binfo);
15264 BINFO_BASE_ACCESS_APPEND (binfo, access);
15265 continue;
15266
15267 dropped_base:
15268 /* Update max_vbases to reflect the reality that we are dropping
15269 this base: if it reaches zero we want to undo the vec_alloc
15270 above to avoid inconsistencies during error-recovery: eg, in
15271 build_special_member_call, CLASSTYPE_VBASECLASSES non null
15272 and vtt null (c++/27952). */
15273 if (via_virtual)
15274 max_vbases--;
15275 if (CLASS_TYPE_P (basetype))
15276 max_vbases
15277 -= vec_safe_length (CLASSTYPE_VBASECLASSES (basetype));
15278 }
15279
15280 if (CLASSTYPE_VBASECLASSES (ref)
15281 && max_vbases == 0)
15282 vec_free (CLASSTYPE_VBASECLASSES (ref));
15283
15284 if (vec_safe_length (CLASSTYPE_VBASECLASSES (ref)) < max_vbases)
15285 /* If we didn't get max_vbases vbases, we must have shared at
15286 least one of them, and are therefore diamond shaped. */
15287 CLASSTYPE_DIAMOND_SHAPED_P (ref) = 1;
15288
15289 /* Unmark all the types. */
15290 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
15291 TYPE_MARKED_P (BINFO_TYPE (base_binfo)) = 0;
15292 TYPE_MARKED_P (ref) = 0;
15293
15294 /* Now see if we have a repeated base type. */
15295 if (!CLASSTYPE_REPEATED_BASE_P (ref))
15296 {
15297 for (base_binfo = binfo; base_binfo;
15298 base_binfo = TREE_CHAIN (base_binfo))
15299 {
15300 if (TYPE_MARKED_P (BINFO_TYPE (base_binfo)))
15301 {
15302 CLASSTYPE_REPEATED_BASE_P (ref) = 1;
15303 break;
15304 }
15305 TYPE_MARKED_P (BINFO_TYPE (base_binfo)) = 1;
15306 }
15307 for (base_binfo = binfo; base_binfo;
15308 base_binfo = TREE_CHAIN (base_binfo))
15309 if (TYPE_MARKED_P (BINFO_TYPE (base_binfo)))
15310 TYPE_MARKED_P (BINFO_TYPE (base_binfo)) = 0;
15311 else
15312 break;
15313 }
15314 }
15315
15316
15317 /* Copies the enum-related properties from type SRC to type DST.
15318 Used with the underlying type of an enum and the enum itself. */
15319 static void
copy_type_enum(tree dst,tree src)15320 copy_type_enum (tree dst, tree src)
15321 {
15322 tree t;
15323 for (t = dst; t; t = TYPE_NEXT_VARIANT (t))
15324 {
15325 TYPE_MIN_VALUE (t) = TYPE_MIN_VALUE (src);
15326 TYPE_MAX_VALUE (t) = TYPE_MAX_VALUE (src);
15327 TYPE_SIZE (t) = TYPE_SIZE (src);
15328 TYPE_SIZE_UNIT (t) = TYPE_SIZE_UNIT (src);
15329 SET_TYPE_MODE (dst, TYPE_MODE (src));
15330 TYPE_PRECISION (t) = TYPE_PRECISION (src);
15331 unsigned valign = TYPE_ALIGN (src);
15332 if (TYPE_USER_ALIGN (t))
15333 valign = MAX (valign, TYPE_ALIGN (t));
15334 else
15335 TYPE_USER_ALIGN (t) = TYPE_USER_ALIGN (src);
15336 SET_TYPE_ALIGN (t, valign);
15337 TYPE_UNSIGNED (t) = TYPE_UNSIGNED (src);
15338 }
15339 }
15340
15341 /* Begin compiling the definition of an enumeration type.
15342 NAME is its name,
15343
15344 if ENUMTYPE is not NULL_TREE then the type has alredy been found.
15345
15346 UNDERLYING_TYPE is the type that will be used as the storage for
15347 the enumeration type. This should be NULL_TREE if no storage type
15348 was specified.
15349
15350 ATTRIBUTES are any attributes specified after the enum-key.
15351
15352 SCOPED_ENUM_P is true if this is a scoped enumeration type.
15353
15354 if IS_NEW is not NULL, gets TRUE iff a new type is created.
15355
15356 Returns the type object, as yet incomplete.
15357 Also records info about it so that build_enumerator
15358 may be used to declare the individual values as they are read. */
15359
15360 tree
start_enum(tree name,tree enumtype,tree underlying_type,tree attributes,bool scoped_enum_p,bool * is_new)15361 start_enum (tree name, tree enumtype, tree underlying_type,
15362 tree attributes, bool scoped_enum_p, bool *is_new)
15363 {
15364 tree prevtype = NULL_TREE;
15365 gcc_assert (identifier_p (name));
15366
15367 if (is_new)
15368 *is_new = false;
15369 /* [C++0x dcl.enum]p5:
15370
15371 If not explicitly specified, the underlying type of a scoped
15372 enumeration type is int. */
15373 if (!underlying_type && scoped_enum_p)
15374 underlying_type = integer_type_node;
15375
15376 if (underlying_type)
15377 underlying_type = cv_unqualified (underlying_type);
15378
15379 /* If this is the real definition for a previous forward reference,
15380 fill in the contents in the same object that used to be the
15381 forward reference. */
15382 if (!enumtype)
15383 enumtype = lookup_and_check_tag (enum_type, name,
15384 /*tag_scope=*/ts_current,
15385 /*template_header_p=*/false);
15386
15387 /* In case of a template_decl, the only check that should be deferred
15388 to instantiation time is the comparison of underlying types. */
15389 if (enumtype && TREE_CODE (enumtype) == ENUMERAL_TYPE)
15390 {
15391 if (scoped_enum_p != SCOPED_ENUM_P (enumtype))
15392 {
15393 error_at (input_location, "scoped/unscoped mismatch "
15394 "in enum %q#T", enumtype);
15395 inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (enumtype)),
15396 "previous definition here");
15397 enumtype = error_mark_node;
15398 }
15399 else if (ENUM_FIXED_UNDERLYING_TYPE_P (enumtype) != !! underlying_type)
15400 {
15401 error_at (input_location, "underlying type mismatch "
15402 "in enum %q#T", enumtype);
15403 inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (enumtype)),
15404 "previous definition here");
15405 enumtype = error_mark_node;
15406 }
15407 else if (underlying_type && ENUM_UNDERLYING_TYPE (enumtype)
15408 && !same_type_p (underlying_type,
15409 ENUM_UNDERLYING_TYPE (enumtype)))
15410 {
15411 error_at (input_location, "different underlying type "
15412 "in enum %q#T", enumtype);
15413 inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (enumtype)),
15414 "previous definition here");
15415 underlying_type = NULL_TREE;
15416 }
15417 }
15418
15419 if (!enumtype || TREE_CODE (enumtype) != ENUMERAL_TYPE
15420 || processing_template_decl)
15421 {
15422 /* In case of error, make a dummy enum to allow parsing to
15423 continue. */
15424 if (enumtype == error_mark_node)
15425 {
15426 name = make_anon_name ();
15427 enumtype = NULL_TREE;
15428 }
15429
15430 /* enumtype may be an ENUMERAL_TYPE if this is a redefinition
15431 of an opaque enum, or an opaque enum of an already defined
15432 enumeration (C++11).
15433 In any other case, it'll be NULL_TREE. */
15434 if (!enumtype)
15435 {
15436 if (is_new)
15437 *is_new = true;
15438 }
15439 prevtype = enumtype;
15440
15441 /* Do not push the decl more than once. */
15442 if (!enumtype
15443 || TREE_CODE (enumtype) != ENUMERAL_TYPE)
15444 {
15445 enumtype = cxx_make_type (ENUMERAL_TYPE);
15446 enumtype = pushtag (name, enumtype, /*tag_scope=*/ts_current);
15447
15448 /* std::byte aliases anything. */
15449 if (enumtype != error_mark_node
15450 && TYPE_CONTEXT (enumtype) == std_node
15451 && !strcmp ("byte", TYPE_NAME_STRING (enumtype)))
15452 TYPE_ALIAS_SET (enumtype) = 0;
15453 }
15454 else
15455 enumtype = xref_tag (enum_type, name, /*tag_scope=*/ts_current,
15456 false);
15457
15458 if (enumtype == error_mark_node)
15459 return error_mark_node;
15460
15461 /* The enum is considered opaque until the opening '{' of the
15462 enumerator list. */
15463 SET_OPAQUE_ENUM_P (enumtype, true);
15464 ENUM_FIXED_UNDERLYING_TYPE_P (enumtype) = !! underlying_type;
15465 }
15466
15467 SET_SCOPED_ENUM_P (enumtype, scoped_enum_p);
15468
15469 cplus_decl_attributes (&enumtype, attributes, (int)ATTR_FLAG_TYPE_IN_PLACE);
15470
15471 if (underlying_type)
15472 {
15473 if (ENUM_UNDERLYING_TYPE (enumtype))
15474 /* We already checked that it matches, don't change it to a different
15475 typedef variant. */;
15476 else if (CP_INTEGRAL_TYPE_P (underlying_type))
15477 {
15478 copy_type_enum (enumtype, underlying_type);
15479 ENUM_UNDERLYING_TYPE (enumtype) = underlying_type;
15480 }
15481 else if (dependent_type_p (underlying_type))
15482 ENUM_UNDERLYING_TYPE (enumtype) = underlying_type;
15483 else
15484 error ("underlying type %qT of %qT must be an integral type",
15485 underlying_type, enumtype);
15486 }
15487
15488 /* If into a template class, the returned enum is always the first
15489 declaration (opaque or not) seen. This way all the references to
15490 this type will be to the same declaration. The following ones are used
15491 only to check for definition errors. */
15492 if (prevtype && processing_template_decl)
15493 return prevtype;
15494 else
15495 return enumtype;
15496 }
15497
15498 /* After processing and defining all the values of an enumeration type,
15499 install their decls in the enumeration type.
15500 ENUMTYPE is the type object. */
15501
15502 void
finish_enum_value_list(tree enumtype)15503 finish_enum_value_list (tree enumtype)
15504 {
15505 tree values;
15506 tree underlying_type;
15507 tree decl;
15508 tree value;
15509 tree minnode, maxnode;
15510 tree t;
15511
15512 bool fixed_underlying_type_p
15513 = ENUM_UNDERLYING_TYPE (enumtype) != NULL_TREE;
15514
15515 /* We built up the VALUES in reverse order. */
15516 TYPE_VALUES (enumtype) = nreverse (TYPE_VALUES (enumtype));
15517
15518 /* For an enum defined in a template, just set the type of the values;
15519 all further processing is postponed until the template is
15520 instantiated. We need to set the type so that tsubst of a CONST_DECL
15521 works. */
15522 if (processing_template_decl)
15523 {
15524 for (values = TYPE_VALUES (enumtype);
15525 values;
15526 values = TREE_CHAIN (values))
15527 TREE_TYPE (TREE_VALUE (values)) = enumtype;
15528 return;
15529 }
15530
15531 /* Determine the minimum and maximum values of the enumerators. */
15532 if (TYPE_VALUES (enumtype))
15533 {
15534 minnode = maxnode = NULL_TREE;
15535
15536 for (values = TYPE_VALUES (enumtype);
15537 values;
15538 values = TREE_CHAIN (values))
15539 {
15540 decl = TREE_VALUE (values);
15541
15542 /* [dcl.enum]: Following the closing brace of an enum-specifier,
15543 each enumerator has the type of its enumeration. Prior to the
15544 closing brace, the type of each enumerator is the type of its
15545 initializing value. */
15546 TREE_TYPE (decl) = enumtype;
15547
15548 /* Update the minimum and maximum values, if appropriate. */
15549 value = DECL_INITIAL (decl);
15550 if (value == error_mark_node)
15551 value = integer_zero_node;
15552 /* Figure out what the minimum and maximum values of the
15553 enumerators are. */
15554 if (!minnode)
15555 minnode = maxnode = value;
15556 else if (tree_int_cst_lt (maxnode, value))
15557 maxnode = value;
15558 else if (tree_int_cst_lt (value, minnode))
15559 minnode = value;
15560 }
15561 }
15562 else
15563 /* [dcl.enum]
15564
15565 If the enumerator-list is empty, the underlying type is as if
15566 the enumeration had a single enumerator with value 0. */
15567 minnode = maxnode = integer_zero_node;
15568
15569 if (!fixed_underlying_type_p)
15570 {
15571 /* Compute the number of bits require to represent all values of the
15572 enumeration. We must do this before the type of MINNODE and
15573 MAXNODE are transformed, since tree_int_cst_min_precision relies
15574 on the TREE_TYPE of the value it is passed. */
15575 signop sgn = tree_int_cst_sgn (minnode) >= 0 ? UNSIGNED : SIGNED;
15576 int lowprec = tree_int_cst_min_precision (minnode, sgn);
15577 int highprec = tree_int_cst_min_precision (maxnode, sgn);
15578 int precision = MAX (lowprec, highprec);
15579 unsigned int itk;
15580 bool use_short_enum;
15581
15582 /* Determine the underlying type of the enumeration.
15583
15584 [dcl.enum]
15585
15586 The underlying type of an enumeration is an integral type that
15587 can represent all the enumerator values defined in the
15588 enumeration. It is implementation-defined which integral type is
15589 used as the underlying type for an enumeration except that the
15590 underlying type shall not be larger than int unless the value of
15591 an enumerator cannot fit in an int or unsigned int.
15592
15593 We use "int" or an "unsigned int" as the underlying type, even if
15594 a smaller integral type would work, unless the user has
15595 explicitly requested that we use the smallest possible type. The
15596 user can request that for all enumerations with a command line
15597 flag, or for just one enumeration with an attribute. */
15598
15599 use_short_enum = flag_short_enums
15600 || lookup_attribute ("packed", TYPE_ATTRIBUTES (enumtype));
15601
15602 /* If the precision of the type was specified with an attribute and it
15603 was too small, give an error. Otherwise, use it. */
15604 if (TYPE_PRECISION (enumtype))
15605 {
15606 if (precision > TYPE_PRECISION (enumtype))
15607 error ("specified mode too small for enumerated values");
15608 else
15609 {
15610 use_short_enum = true;
15611 precision = TYPE_PRECISION (enumtype);
15612 }
15613 }
15614
15615 for (itk = (use_short_enum ? itk_char : itk_int);
15616 itk != itk_none;
15617 itk++)
15618 {
15619 underlying_type = integer_types[itk];
15620 if (underlying_type != NULL_TREE
15621 && TYPE_PRECISION (underlying_type) >= precision
15622 && TYPE_SIGN (underlying_type) == sgn)
15623 break;
15624 }
15625 if (itk == itk_none)
15626 {
15627 /* DR 377
15628
15629 IF no integral type can represent all the enumerator values, the
15630 enumeration is ill-formed. */
15631 error ("no integral type can represent all of the enumerator values "
15632 "for %qT", enumtype);
15633 precision = TYPE_PRECISION (long_long_integer_type_node);
15634 underlying_type = integer_types[itk_unsigned_long_long];
15635 }
15636
15637 /* [dcl.enum]
15638
15639 The value of sizeof() applied to an enumeration type, an object
15640 of an enumeration type, or an enumerator, is the value of sizeof()
15641 applied to the underlying type. */
15642 copy_type_enum (enumtype, underlying_type);
15643
15644 /* Compute the minimum and maximum values for the type.
15645
15646 [dcl.enum]
15647
15648 For an enumeration where emin is the smallest enumerator and emax
15649 is the largest, the values of the enumeration are the values of the
15650 underlying type in the range bmin to bmax, where bmin and bmax are,
15651 respectively, the smallest and largest values of the smallest bit-
15652 field that can store emin and emax. */
15653
15654 /* The middle-end currently assumes that types with TYPE_PRECISION
15655 narrower than their underlying type are suitably zero or sign
15656 extended to fill their mode. Similarly, it assumes that the front
15657 end assures that a value of a particular type must be within
15658 TYPE_MIN_VALUE and TYPE_MAX_VALUE.
15659
15660 We used to set these fields based on bmin and bmax, but that led
15661 to invalid assumptions like optimizing away bounds checking. So
15662 now we just set the TYPE_PRECISION, TYPE_MIN_VALUE, and
15663 TYPE_MAX_VALUE to the values for the mode above and only restrict
15664 the ENUM_UNDERLYING_TYPE for the benefit of diagnostics. */
15665 ENUM_UNDERLYING_TYPE (enumtype)
15666 = build_distinct_type_copy (underlying_type);
15667 TYPE_PRECISION (ENUM_UNDERLYING_TYPE (enumtype)) = precision;
15668 set_min_and_max_values_for_integral_type
15669 (ENUM_UNDERLYING_TYPE (enumtype), precision, sgn);
15670
15671 /* If -fstrict-enums, still constrain TYPE_MIN/MAX_VALUE. */
15672 if (flag_strict_enums)
15673 set_min_and_max_values_for_integral_type (enumtype, precision, sgn);
15674 }
15675 else
15676 underlying_type = ENUM_UNDERLYING_TYPE (enumtype);
15677
15678 /* Convert each of the enumerators to the type of the underlying
15679 type of the enumeration. */
15680 for (values = TYPE_VALUES (enumtype); values; values = TREE_CHAIN (values))
15681 {
15682 decl = TREE_VALUE (values);
15683 iloc_sentinel ils (DECL_SOURCE_LOCATION (decl));
15684 if (fixed_underlying_type_p)
15685 /* If the enumeration type has a fixed underlying type, we
15686 already checked all of the enumerator values. */
15687 value = DECL_INITIAL (decl);
15688 else
15689 value = perform_implicit_conversion (underlying_type,
15690 DECL_INITIAL (decl),
15691 tf_warning_or_error);
15692 /* Do not clobber shared ints. */
15693 if (value != error_mark_node)
15694 {
15695 value = copy_node (value);
15696
15697 TREE_TYPE (value) = enumtype;
15698 }
15699 DECL_INITIAL (decl) = value;
15700 }
15701
15702 /* Fix up all variant types of this enum type. */
15703 for (t = TYPE_MAIN_VARIANT (enumtype); t; t = TYPE_NEXT_VARIANT (t))
15704 TYPE_VALUES (t) = TYPE_VALUES (enumtype);
15705
15706 if (at_class_scope_p ()
15707 && COMPLETE_TYPE_P (current_class_type)
15708 && UNSCOPED_ENUM_P (enumtype))
15709 {
15710 insert_late_enum_def_bindings (current_class_type, enumtype);
15711 /* TYPE_FIELDS needs fixup. */
15712 fixup_type_variants (current_class_type);
15713 }
15714
15715 /* Finish debugging output for this type. */
15716 rest_of_type_compilation (enumtype, namespace_bindings_p ());
15717
15718 /* Each enumerator now has the type of its enumeration. Clear the cache
15719 so that this change in types doesn't confuse us later on. */
15720 clear_cv_and_fold_caches ();
15721 }
15722
15723 /* Finishes the enum type. This is called only the first time an
15724 enumeration is seen, be it opaque or odinary.
15725 ENUMTYPE is the type object. */
15726
15727 void
finish_enum(tree enumtype)15728 finish_enum (tree enumtype)
15729 {
15730 if (processing_template_decl)
15731 {
15732 if (at_function_scope_p ())
15733 add_stmt (build_min (TAG_DEFN, enumtype));
15734 return;
15735 }
15736
15737 /* If this is a forward declaration, there should not be any variants,
15738 though we can get a variant in the middle of an enum-specifier with
15739 wacky code like 'enum E { e = sizeof(const E*) };' */
15740 gcc_assert (enumtype == TYPE_MAIN_VARIANT (enumtype)
15741 && (TYPE_VALUES (enumtype)
15742 || !TYPE_NEXT_VARIANT (enumtype)));
15743 }
15744
15745 /* Build and install a CONST_DECL for an enumeration constant of the
15746 enumeration type ENUMTYPE whose NAME and VALUE (if any) are provided.
15747 Apply ATTRIBUTES if available. LOC is the location of NAME.
15748 Assignment of sequential values by default is handled here. */
15749
15750 void
build_enumerator(tree name,tree value,tree enumtype,tree attributes,location_t loc)15751 build_enumerator (tree name, tree value, tree enumtype, tree attributes,
15752 location_t loc)
15753 {
15754 tree decl;
15755 tree context;
15756 tree type;
15757
15758 /* scalar_constant_value will pull out this expression, so make sure
15759 it's folded as appropriate. */
15760 if (processing_template_decl)
15761 value = fold_non_dependent_expr (value);
15762
15763 /* If the VALUE was erroneous, pretend it wasn't there; that will
15764 result in the enum being assigned the next value in sequence. */
15765 if (value == error_mark_node)
15766 value = NULL_TREE;
15767
15768 /* Remove no-op casts from the value. */
15769 if (value)
15770 STRIP_TYPE_NOPS (value);
15771
15772 if (! processing_template_decl)
15773 {
15774 /* Validate and default VALUE. */
15775 if (value != NULL_TREE)
15776 {
15777 if (!ENUM_UNDERLYING_TYPE (enumtype))
15778 {
15779 tree tmp_value = build_expr_type_conversion (WANT_INT | WANT_ENUM,
15780 value, true);
15781 if (tmp_value)
15782 value = tmp_value;
15783 }
15784 else if (! INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P
15785 (TREE_TYPE (value)))
15786 value = perform_implicit_conversion_flags
15787 (ENUM_UNDERLYING_TYPE (enumtype), value, tf_warning_or_error,
15788 LOOKUP_IMPLICIT | LOOKUP_NO_NARROWING);
15789
15790 if (value == error_mark_node)
15791 value = NULL_TREE;
15792
15793 if (value != NULL_TREE)
15794 {
15795 if (! INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P
15796 (TREE_TYPE (value)))
15797 {
15798 error_at (cp_expr_loc_or_input_loc (value),
15799 "enumerator value for %qD must have integral or "
15800 "unscoped enumeration type", name);
15801 value = NULL_TREE;
15802 }
15803 else
15804 {
15805 value = cxx_constant_value (value);
15806
15807 if (TREE_CODE (value) != INTEGER_CST)
15808 {
15809 error ("enumerator value for %qD is not an integer "
15810 "constant", name);
15811 value = NULL_TREE;
15812 }
15813 }
15814 }
15815 }
15816
15817 /* Default based on previous value. */
15818 if (value == NULL_TREE)
15819 {
15820 if (TYPE_VALUES (enumtype))
15821 {
15822 tree prev_value;
15823
15824 /* C++03 7.2/4: If no initializer is specified for the first
15825 enumerator, the type is an unspecified integral
15826 type. Otherwise the type is the same as the type of the
15827 initializing value of the preceding enumerator unless the
15828 incremented value is not representable in that type, in
15829 which case the type is an unspecified integral type
15830 sufficient to contain the incremented value. */
15831 prev_value = DECL_INITIAL (TREE_VALUE (TYPE_VALUES (enumtype)));
15832 if (error_operand_p (prev_value))
15833 value = error_mark_node;
15834 else
15835 {
15836 wi::overflow_type overflowed;
15837 tree type = TREE_TYPE (prev_value);
15838 signop sgn = TYPE_SIGN (type);
15839 widest_int wi = wi::add (wi::to_widest (prev_value), 1, sgn,
15840 &overflowed);
15841 if (!overflowed)
15842 {
15843 bool pos = !wi::neg_p (wi, sgn);
15844 if (!wi::fits_to_tree_p (wi, type))
15845 {
15846 unsigned int itk;
15847 for (itk = itk_int; itk != itk_none; itk++)
15848 {
15849 type = integer_types[itk];
15850 if (type != NULL_TREE
15851 && (pos || !TYPE_UNSIGNED (type))
15852 && wi::fits_to_tree_p (wi, type))
15853 break;
15854 }
15855 if (type && cxx_dialect < cxx11
15856 && itk > itk_unsigned_long)
15857 pedwarn (input_location, OPT_Wlong_long,
15858 pos ? G_("\
15859 incremented enumerator value is too large for %<unsigned long%>") : G_("\
15860 incremented enumerator value is too large for %<long%>"));
15861 }
15862 if (type == NULL_TREE)
15863 overflowed = wi::OVF_UNKNOWN;
15864 else
15865 value = wide_int_to_tree (type, wi);
15866 }
15867
15868 if (overflowed)
15869 {
15870 error ("overflow in enumeration values at %qD", name);
15871 value = error_mark_node;
15872 }
15873 }
15874 }
15875 else
15876 value = integer_zero_node;
15877 }
15878
15879 /* Remove no-op casts from the value. */
15880 STRIP_TYPE_NOPS (value);
15881
15882 /* If the underlying type of the enum is fixed, check whether
15883 the enumerator values fits in the underlying type. If it
15884 does not fit, the program is ill-formed [C++0x dcl.enum]. */
15885 if (ENUM_UNDERLYING_TYPE (enumtype)
15886 && value
15887 && TREE_CODE (value) == INTEGER_CST)
15888 {
15889 if (!int_fits_type_p (value, ENUM_UNDERLYING_TYPE (enumtype)))
15890 error ("enumerator value %qE is outside the range of underlying "
15891 "type %qT", value, ENUM_UNDERLYING_TYPE (enumtype));
15892
15893 /* Convert the value to the appropriate type. */
15894 value = fold_convert (ENUM_UNDERLYING_TYPE (enumtype), value);
15895 }
15896 }
15897
15898 /* C++ associates enums with global, function, or class declarations. */
15899 context = current_scope ();
15900
15901 /* Build the actual enumeration constant. Note that the enumeration
15902 constants have the underlying type of the enum (if it is fixed)
15903 or the type of their initializer (if the underlying type of the
15904 enum is not fixed):
15905
15906 [ C++0x dcl.enum ]
15907
15908 If the underlying type is fixed, the type of each enumerator
15909 prior to the closing brace is the underlying type; if the
15910 initializing value of an enumerator cannot be represented by
15911 the underlying type, the program is ill-formed. If the
15912 underlying type is not fixed, the type of each enumerator is
15913 the type of its initializing value.
15914
15915 If the underlying type is not fixed, it will be computed by
15916 finish_enum and we will reset the type of this enumerator. Of
15917 course, if we're processing a template, there may be no value. */
15918 type = value ? TREE_TYPE (value) : NULL_TREE;
15919
15920 decl = build_decl (loc, CONST_DECL, name, type);
15921
15922 DECL_CONTEXT (decl) = enumtype;
15923 TREE_CONSTANT (decl) = 1;
15924 TREE_READONLY (decl) = 1;
15925 DECL_INITIAL (decl) = value;
15926
15927 if (attributes)
15928 cplus_decl_attributes (&decl, attributes, 0);
15929
15930 if (context && context == current_class_type && !SCOPED_ENUM_P (enumtype))
15931 {
15932 /* In something like `struct S { enum E { i = 7 }; };' we put `i'
15933 on the TYPE_FIELDS list for `S'. (That's so that you can say
15934 things like `S::i' later.) */
15935
15936 /* The enumerator may be getting declared outside of its enclosing
15937 class, like so:
15938
15939 class S { public: enum E : int; }; enum S::E : int { i = 7; };
15940
15941 For which case we need to make sure that the access of `S::i'
15942 matches the access of `S::E'. */
15943 tree saved_cas = current_access_specifier;
15944 if (TREE_PRIVATE (TYPE_NAME (enumtype)))
15945 current_access_specifier = access_private_node;
15946 else if (TREE_PROTECTED (TYPE_NAME (enumtype)))
15947 current_access_specifier = access_protected_node;
15948 else
15949 current_access_specifier = access_public_node;
15950
15951 finish_member_declaration (decl);
15952
15953 current_access_specifier = saved_cas;
15954 }
15955 else
15956 pushdecl (decl);
15957
15958 /* Add this enumeration constant to the list for this type. */
15959 TYPE_VALUES (enumtype) = tree_cons (name, decl, TYPE_VALUES (enumtype));
15960 }
15961
15962 /* Look for an enumerator with the given NAME within the enumeration
15963 type ENUMTYPE. This routine is used primarily for qualified name
15964 lookup into an enumerator in C++0x, e.g.,
15965
15966 enum class Color { Red, Green, Blue };
15967
15968 Color color = Color::Red;
15969
15970 Returns the value corresponding to the enumerator, or
15971 NULL_TREE if no such enumerator was found. */
15972 tree
lookup_enumerator(tree enumtype,tree name)15973 lookup_enumerator (tree enumtype, tree name)
15974 {
15975 tree e;
15976 gcc_assert (enumtype && TREE_CODE (enumtype) == ENUMERAL_TYPE);
15977
15978 e = purpose_member (name, TYPE_VALUES (enumtype));
15979 return e? TREE_VALUE (e) : NULL_TREE;
15980 }
15981
15982 /* Implement LANG_HOOKS_SIMULATE_ENUM_DECL. */
15983
15984 tree
cxx_simulate_enum_decl(location_t loc,const char * name,vec<string_int_pair> values)15985 cxx_simulate_enum_decl (location_t loc, const char *name,
15986 vec<string_int_pair> values)
15987 {
15988 location_t saved_loc = input_location;
15989 input_location = loc;
15990
15991 tree enumtype = start_enum (get_identifier (name), NULL_TREE, NULL_TREE,
15992 NULL_TREE, false, NULL);
15993 if (!OPAQUE_ENUM_P (enumtype))
15994 {
15995 error_at (loc, "multiple definition of %q#T", enumtype);
15996 inform (DECL_SOURCE_LOCATION (TYPE_MAIN_DECL (enumtype)),
15997 "previous definition here");
15998 return enumtype;
15999 }
16000 SET_OPAQUE_ENUM_P (enumtype, false);
16001 DECL_SOURCE_LOCATION (TYPE_NAME (enumtype)) = loc;
16002
16003 string_int_pair *value;
16004 unsigned int i;
16005 FOR_EACH_VEC_ELT (values, i, value)
16006 build_enumerator (get_identifier (value->first),
16007 build_int_cst (integer_type_node, value->second),
16008 enumtype, NULL_TREE, loc);
16009
16010 finish_enum_value_list (enumtype);
16011 finish_enum (enumtype);
16012
16013 input_location = saved_loc;
16014 return enumtype;
16015 }
16016
16017 /* We're defining DECL. Make sure that its type is OK. */
16018
16019 static void
check_function_type(tree decl,tree current_function_parms)16020 check_function_type (tree decl, tree current_function_parms)
16021 {
16022 tree fntype = TREE_TYPE (decl);
16023 tree return_type = complete_type (TREE_TYPE (fntype));
16024
16025 /* In a function definition, arg types must be complete. */
16026 require_complete_types_for_parms (current_function_parms);
16027
16028 if (dependent_type_p (return_type)
16029 || type_uses_auto (return_type))
16030 return;
16031 if (!COMPLETE_OR_VOID_TYPE_P (return_type))
16032 {
16033 tree args = TYPE_ARG_TYPES (fntype);
16034
16035 error ("return type %q#T is incomplete", return_type);
16036
16037 /* Make it return void instead. */
16038 if (TREE_CODE (fntype) == METHOD_TYPE)
16039 fntype = build_method_type_directly (TREE_TYPE (TREE_VALUE (args)),
16040 void_type_node,
16041 TREE_CHAIN (args));
16042 else
16043 fntype = build_function_type (void_type_node, args);
16044 fntype = (cp_build_type_attribute_variant
16045 (fntype, TYPE_ATTRIBUTES (TREE_TYPE (decl))));
16046 fntype = cxx_copy_lang_qualifiers (fntype, TREE_TYPE (decl));
16047 TREE_TYPE (decl) = fntype;
16048 }
16049 else
16050 {
16051 abstract_virtuals_error (decl, TREE_TYPE (fntype));
16052 maybe_warn_parm_abi (TREE_TYPE (fntype),
16053 DECL_SOURCE_LOCATION (decl));
16054 }
16055 }
16056
16057 /* True iff FN is an implicitly-defined default constructor. */
16058
16059 static bool
implicit_default_ctor_p(tree fn)16060 implicit_default_ctor_p (tree fn)
16061 {
16062 return (DECL_CONSTRUCTOR_P (fn)
16063 && !user_provided_p (fn)
16064 && sufficient_parms_p (FUNCTION_FIRST_USER_PARMTYPE (fn)));
16065 }
16066
16067 /* Clobber the contents of *this to let the back end know that the object
16068 storage is dead when we enter the constructor or leave the destructor. */
16069
16070 static tree
build_clobber_this()16071 build_clobber_this ()
16072 {
16073 /* Clobbering an empty base is pointless, and harmful if its one byte
16074 TYPE_SIZE overlays real data. */
16075 if (is_empty_class (current_class_type))
16076 return void_node;
16077
16078 /* If we have virtual bases, clobber the whole object, but only if we're in
16079 charge. If we don't have virtual bases, clobber the as-base type so we
16080 don't mess with tail padding. */
16081 bool vbases = CLASSTYPE_VBASECLASSES (current_class_type);
16082
16083 tree ctype = current_class_type;
16084 if (!vbases)
16085 ctype = CLASSTYPE_AS_BASE (ctype);
16086
16087 tree clobber = build_clobber (ctype);
16088
16089 tree thisref = current_class_ref;
16090 if (ctype != current_class_type)
16091 {
16092 thisref = build_nop (build_reference_type (ctype), current_class_ptr);
16093 thisref = convert_from_reference (thisref);
16094 }
16095
16096 tree exprstmt = build2 (MODIFY_EXPR, void_type_node, thisref, clobber);
16097 if (vbases)
16098 exprstmt = build_if_in_charge (exprstmt);
16099
16100 return exprstmt;
16101 }
16102
16103 /* Create the FUNCTION_DECL for a function definition.
16104 DECLSPECS and DECLARATOR are the parts of the declaration;
16105 they describe the function's name and the type it returns,
16106 but twisted together in a fashion that parallels the syntax of C.
16107
16108 FLAGS is a bitwise or of SF_PRE_PARSED (indicating that the
16109 DECLARATOR is really the DECL for the function we are about to
16110 process and that DECLSPECS should be ignored), SF_INCLASS_INLINE
16111 indicating that the function is an inline defined in-class.
16112
16113 This function creates a binding context for the function body
16114 as well as setting up the FUNCTION_DECL in current_function_decl.
16115
16116 For C++, we must first check whether that datum makes any sense.
16117 For example, "class A local_a(1,2);" means that variable local_a
16118 is an aggregate of type A, which should have a constructor
16119 applied to it with the argument list [1, 2].
16120
16121 On entry, DECL_INITIAL (decl1) should be NULL_TREE or error_mark_node,
16122 or may be a BLOCK if the function has been defined previously
16123 in this translation unit. On exit, DECL_INITIAL (decl1) will be
16124 error_mark_node if the function has never been defined, or
16125 a BLOCK if the function has been defined somewhere. */
16126
16127 bool
start_preparsed_function(tree decl1,tree attrs,int flags)16128 start_preparsed_function (tree decl1, tree attrs, int flags)
16129 {
16130 tree ctype = NULL_TREE;
16131 tree fntype;
16132 tree restype;
16133 int doing_friend = 0;
16134 cp_binding_level *bl;
16135 tree current_function_parms;
16136 struct c_fileinfo *finfo
16137 = get_fileinfo (LOCATION_FILE (DECL_SOURCE_LOCATION (decl1)));
16138 bool honor_interface;
16139
16140 /* Sanity check. */
16141 gcc_assert (VOID_TYPE_P (TREE_VALUE (void_list_node)));
16142 gcc_assert (TREE_CHAIN (void_list_node) == NULL_TREE);
16143
16144 fntype = TREE_TYPE (decl1);
16145 if (TREE_CODE (fntype) == METHOD_TYPE)
16146 ctype = TYPE_METHOD_BASETYPE (fntype);
16147
16148 /* ISO C++ 11.4/5. A friend function defined in a class is in
16149 the (lexical) scope of the class in which it is defined. */
16150 if (!ctype && DECL_FRIEND_P (decl1))
16151 {
16152 ctype = DECL_FRIEND_CONTEXT (decl1);
16153
16154 /* CTYPE could be null here if we're dealing with a template;
16155 for example, `inline friend float foo()' inside a template
16156 will have no CTYPE set. */
16157 if (ctype && TREE_CODE (ctype) != RECORD_TYPE)
16158 ctype = NULL_TREE;
16159 else
16160 doing_friend = 1;
16161 }
16162
16163 if (DECL_DECLARED_INLINE_P (decl1)
16164 && lookup_attribute ("noinline", attrs))
16165 warning_at (DECL_SOURCE_LOCATION (decl1), 0,
16166 "inline function %qD given attribute %qs", decl1, "noinline");
16167
16168 /* Handle gnu_inline attribute. */
16169 if (GNU_INLINE_P (decl1))
16170 {
16171 DECL_EXTERNAL (decl1) = 1;
16172 DECL_NOT_REALLY_EXTERN (decl1) = 0;
16173 DECL_INTERFACE_KNOWN (decl1) = 1;
16174 DECL_DISREGARD_INLINE_LIMITS (decl1) = 1;
16175 }
16176
16177 if (DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (decl1))
16178 /* This is a constructor, we must ensure that any default args
16179 introduced by this definition are propagated to the clones
16180 now. The clones are used directly in overload resolution. */
16181 adjust_clone_args (decl1);
16182
16183 /* Sometimes we don't notice that a function is a static member, and
16184 build a METHOD_TYPE for it. Fix that up now. */
16185 gcc_assert (!(ctype != NULL_TREE && DECL_STATIC_FUNCTION_P (decl1)
16186 && TREE_CODE (TREE_TYPE (decl1)) == METHOD_TYPE));
16187
16188 /* Set up current_class_type, and enter the scope of the class, if
16189 appropriate. */
16190 if (ctype)
16191 push_nested_class (ctype);
16192 else if (DECL_STATIC_FUNCTION_P (decl1))
16193 push_nested_class (DECL_CONTEXT (decl1));
16194
16195 /* Now that we have entered the scope of the class, we must restore
16196 the bindings for any template parameters surrounding DECL1, if it
16197 is an inline member template. (Order is important; consider the
16198 case where a template parameter has the same name as a field of
16199 the class.) It is not until after this point that
16200 PROCESSING_TEMPLATE_DECL is guaranteed to be set up correctly. */
16201 if (flags & SF_INCLASS_INLINE)
16202 maybe_begin_member_template_processing (decl1);
16203
16204 /* Effective C++ rule 15. */
16205 if (warn_ecpp
16206 && DECL_ASSIGNMENT_OPERATOR_P (decl1)
16207 && DECL_OVERLOADED_OPERATOR_IS (decl1, NOP_EXPR)
16208 && VOID_TYPE_P (TREE_TYPE (fntype)))
16209 warning (OPT_Weffc__,
16210 "%<operator=%> should return a reference to %<*this%>");
16211
16212 /* Make the init_value nonzero so pushdecl knows this is not tentative.
16213 error_mark_node is replaced below (in poplevel) with the BLOCK. */
16214 if (!DECL_INITIAL (decl1))
16215 DECL_INITIAL (decl1) = error_mark_node;
16216
16217 /* This function exists in static storage.
16218 (This does not mean `static' in the C sense!) */
16219 TREE_STATIC (decl1) = 1;
16220
16221 /* We must call push_template_decl after current_class_type is set
16222 up. (If we are processing inline definitions after exiting a
16223 class scope, current_class_type will be NULL_TREE until set above
16224 by push_nested_class.) */
16225 if (processing_template_decl)
16226 {
16227 tree newdecl1 = push_template_decl (decl1);
16228 if (newdecl1 == error_mark_node)
16229 {
16230 if (ctype || DECL_STATIC_FUNCTION_P (decl1))
16231 pop_nested_class ();
16232 return false;
16233 }
16234 decl1 = newdecl1;
16235 }
16236
16237 /* Make sure the parameter and return types are reasonable. When
16238 you declare a function, these types can be incomplete, but they
16239 must be complete when you define the function. */
16240 check_function_type (decl1, DECL_ARGUMENTS (decl1));
16241
16242 /* Build the return declaration for the function. */
16243 restype = TREE_TYPE (fntype);
16244
16245 if (DECL_RESULT (decl1) == NULL_TREE)
16246 {
16247 tree resdecl;
16248
16249 resdecl = build_decl (input_location, RESULT_DECL, 0, restype);
16250 DECL_ARTIFICIAL (resdecl) = 1;
16251 DECL_IGNORED_P (resdecl) = 1;
16252 DECL_RESULT (decl1) = resdecl;
16253
16254 cp_apply_type_quals_to_decl (cp_type_quals (restype), resdecl);
16255 }
16256
16257 /* Record the decl so that the function name is defined.
16258 If we already have a decl for this name, and it is a FUNCTION_DECL,
16259 use the old decl. */
16260 if (!processing_template_decl && !(flags & SF_PRE_PARSED))
16261 {
16262 /* A specialization is not used to guide overload resolution. */
16263 if (!DECL_FUNCTION_MEMBER_P (decl1)
16264 && !(DECL_USE_TEMPLATE (decl1) &&
16265 PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl1))))
16266 {
16267 tree olddecl = pushdecl (decl1);
16268
16269 if (olddecl == error_mark_node)
16270 /* If something went wrong when registering the declaration,
16271 use DECL1; we have to have a FUNCTION_DECL to use when
16272 parsing the body of the function. */
16273 ;
16274 else
16275 {
16276 /* Otherwise, OLDDECL is either a previous declaration
16277 of the same function or DECL1 itself. */
16278
16279 if (warn_missing_declarations
16280 && olddecl == decl1
16281 && !DECL_MAIN_P (decl1)
16282 && TREE_PUBLIC (decl1)
16283 && !DECL_DECLARED_INLINE_P (decl1))
16284 {
16285 tree context;
16286
16287 /* Check whether DECL1 is in an anonymous
16288 namespace. */
16289 for (context = DECL_CONTEXT (decl1);
16290 context;
16291 context = DECL_CONTEXT (context))
16292 {
16293 if (TREE_CODE (context) == NAMESPACE_DECL
16294 && DECL_NAME (context) == NULL_TREE)
16295 break;
16296 }
16297
16298 if (context == NULL)
16299 warning_at (DECL_SOURCE_LOCATION (decl1),
16300 OPT_Wmissing_declarations,
16301 "no previous declaration for %qD", decl1);
16302 }
16303
16304 decl1 = olddecl;
16305 }
16306 }
16307 else
16308 {
16309 /* We need to set the DECL_CONTEXT. */
16310 if (!DECL_CONTEXT (decl1) && DECL_TEMPLATE_INFO (decl1))
16311 DECL_CONTEXT (decl1) = DECL_CONTEXT (DECL_TI_TEMPLATE (decl1));
16312 }
16313 fntype = TREE_TYPE (decl1);
16314 restype = TREE_TYPE (fntype);
16315
16316 /* If #pragma weak applies, mark the decl appropriately now.
16317 The pragma only applies to global functions. Because
16318 determining whether or not the #pragma applies involves
16319 computing the mangled name for the declaration, we cannot
16320 apply the pragma until after we have merged this declaration
16321 with any previous declarations; if the original declaration
16322 has a linkage specification, that specification applies to
16323 the definition as well, and may affect the mangled name. */
16324 if (DECL_FILE_SCOPE_P (decl1))
16325 maybe_apply_pragma_weak (decl1);
16326 }
16327
16328 /* We are now in the scope of the function being defined. */
16329 current_function_decl = decl1;
16330
16331 /* Save the parm names or decls from this function's declarator
16332 where store_parm_decls will find them. */
16333 current_function_parms = DECL_ARGUMENTS (decl1);
16334
16335 /* Let the user know we're compiling this function. */
16336 announce_function (decl1);
16337
16338 gcc_assert (DECL_INITIAL (decl1));
16339
16340 /* This function may already have been parsed, in which case just
16341 return; our caller will skip over the body without parsing. */
16342 if (DECL_INITIAL (decl1) != error_mark_node)
16343 return true;
16344
16345 /* Initialize RTL machinery. We cannot do this until
16346 CURRENT_FUNCTION_DECL and DECL_RESULT are set up. We do this
16347 even when processing a template; this is how we get
16348 CFUN set up, and our per-function variables initialized.
16349 FIXME factor out the non-RTL stuff. */
16350 bl = current_binding_level;
16351 allocate_struct_function (decl1, processing_template_decl);
16352
16353 /* Initialize the language data structures. Whenever we start
16354 a new function, we destroy temporaries in the usual way. */
16355 cfun->language = ggc_cleared_alloc<language_function> ();
16356 current_stmt_tree ()->stmts_are_full_exprs_p = 1;
16357 current_binding_level = bl;
16358
16359 /* If we are (erroneously) defining a function that we have already
16360 defined before, wipe out what we knew before. */
16361 gcc_checking_assert (!DECL_PENDING_INLINE_P (decl1));
16362 FNDECL_USED_AUTO (decl1) = false;
16363 DECL_SAVED_AUTO_RETURN_TYPE (decl1) = NULL;
16364
16365 if (!processing_template_decl && type_uses_auto (restype))
16366 {
16367 FNDECL_USED_AUTO (decl1) = true;
16368 DECL_SAVED_AUTO_RETURN_TYPE (decl1) = restype;
16369 }
16370
16371 /* Start the statement-tree, start the tree now. */
16372 DECL_SAVED_TREE (decl1) = push_stmt_list ();
16373
16374 if (ctype && !doing_friend && !DECL_STATIC_FUNCTION_P (decl1))
16375 {
16376 /* We know that this was set up by `grokclassfn'. We do not
16377 wait until `store_parm_decls', since evil parse errors may
16378 never get us to that point. Here we keep the consistency
16379 between `current_class_type' and `current_class_ptr'. */
16380 tree t = DECL_ARGUMENTS (decl1);
16381
16382 gcc_assert (t != NULL_TREE && TREE_CODE (t) == PARM_DECL);
16383 gcc_assert (TYPE_PTR_P (TREE_TYPE (t)));
16384
16385 cp_function_chain->x_current_class_ref
16386 = cp_build_fold_indirect_ref (t);
16387 /* Set this second to avoid shortcut in cp_build_indirect_ref. */
16388 cp_function_chain->x_current_class_ptr = t;
16389
16390 /* Constructors and destructors need to know whether they're "in
16391 charge" of initializing virtual base classes. */
16392 t = DECL_CHAIN (t);
16393 if (DECL_HAS_IN_CHARGE_PARM_P (decl1))
16394 {
16395 current_in_charge_parm = t;
16396 t = DECL_CHAIN (t);
16397 }
16398 if (DECL_HAS_VTT_PARM_P (decl1))
16399 {
16400 gcc_assert (DECL_NAME (t) == vtt_parm_identifier);
16401 current_vtt_parm = t;
16402 }
16403 }
16404
16405 honor_interface = (!DECL_TEMPLATE_INSTANTIATION (decl1)
16406 /* Implicitly-defined methods (like the
16407 destructor for a class in which no destructor
16408 is explicitly declared) must not be defined
16409 until their definition is needed. So, we
16410 ignore interface specifications for
16411 compiler-generated functions. */
16412 && !DECL_ARTIFICIAL (decl1));
16413
16414 if (processing_template_decl)
16415 /* Don't mess with interface flags. */;
16416 else if (DECL_INTERFACE_KNOWN (decl1))
16417 {
16418 tree ctx = decl_function_context (decl1);
16419
16420 if (DECL_NOT_REALLY_EXTERN (decl1))
16421 DECL_EXTERNAL (decl1) = 0;
16422
16423 if (ctx != NULL_TREE && vague_linkage_p (ctx))
16424 /* This is a function in a local class in an extern inline
16425 or template function. */
16426 comdat_linkage (decl1);
16427 }
16428 /* If this function belongs to an interface, it is public.
16429 If it belongs to someone else's interface, it is also external.
16430 This only affects inlines and template instantiations. */
16431 else if (!finfo->interface_unknown && honor_interface)
16432 {
16433 if (DECL_DECLARED_INLINE_P (decl1)
16434 || DECL_TEMPLATE_INSTANTIATION (decl1))
16435 {
16436 DECL_EXTERNAL (decl1)
16437 = (finfo->interface_only
16438 || (DECL_DECLARED_INLINE_P (decl1)
16439 && ! flag_implement_inlines
16440 && !DECL_VINDEX (decl1)));
16441
16442 /* For WIN32 we also want to put these in linkonce sections. */
16443 maybe_make_one_only (decl1);
16444 }
16445 else
16446 DECL_EXTERNAL (decl1) = 0;
16447 DECL_INTERFACE_KNOWN (decl1) = 1;
16448 /* If this function is in an interface implemented in this file,
16449 make sure that the back end knows to emit this function
16450 here. */
16451 if (!DECL_EXTERNAL (decl1))
16452 mark_needed (decl1);
16453 }
16454 else if (finfo->interface_unknown && finfo->interface_only
16455 && honor_interface)
16456 {
16457 /* If MULTIPLE_SYMBOL_SPACES is defined and we saw a #pragma
16458 interface, we will have both finfo->interface_unknown and
16459 finfo->interface_only set. In that case, we don't want to
16460 use the normal heuristics because someone will supply a
16461 #pragma implementation elsewhere, and deducing it here would
16462 produce a conflict. */
16463 comdat_linkage (decl1);
16464 DECL_EXTERNAL (decl1) = 0;
16465 DECL_INTERFACE_KNOWN (decl1) = 1;
16466 DECL_DEFER_OUTPUT (decl1) = 1;
16467 }
16468 else
16469 {
16470 /* This is a definition, not a reference.
16471 So clear DECL_EXTERNAL, unless this is a GNU extern inline. */
16472 if (!GNU_INLINE_P (decl1))
16473 DECL_EXTERNAL (decl1) = 0;
16474
16475 if ((DECL_DECLARED_INLINE_P (decl1)
16476 || DECL_TEMPLATE_INSTANTIATION (decl1))
16477 && ! DECL_INTERFACE_KNOWN (decl1))
16478 DECL_DEFER_OUTPUT (decl1) = 1;
16479 else
16480 DECL_INTERFACE_KNOWN (decl1) = 1;
16481 }
16482
16483 /* Determine the ELF visibility attribute for the function. We must not
16484 do this before calling "pushdecl", as we must allow "duplicate_decls"
16485 to merge any attributes appropriately. We also need to wait until
16486 linkage is set. */
16487 if (!DECL_CLONED_FUNCTION_P (decl1))
16488 determine_visibility (decl1);
16489
16490 if (!processing_template_decl)
16491 maybe_instantiate_noexcept (decl1);
16492
16493 begin_scope (sk_function_parms, decl1);
16494
16495 ++function_depth;
16496
16497 if (DECL_DESTRUCTOR_P (decl1)
16498 || (DECL_CONSTRUCTOR_P (decl1)
16499 && targetm.cxx.cdtor_returns_this ()))
16500 {
16501 cdtor_label = create_artificial_label (input_location);
16502 LABEL_DECL_CDTOR (cdtor_label) = true;
16503 }
16504
16505 start_fname_decls ();
16506
16507 store_parm_decls (current_function_parms);
16508
16509 push_operator_bindings ();
16510
16511 if (!processing_template_decl
16512 && (flag_lifetime_dse > 1)
16513 && DECL_CONSTRUCTOR_P (decl1)
16514 && !DECL_CLONED_FUNCTION_P (decl1)
16515 /* Clobbering an empty base is harmful if it overlays real data. */
16516 && !is_empty_class (current_class_type)
16517 /* We can't clobber safely for an implicitly-defined default constructor
16518 because part of the initialization might happen before we enter the
16519 constructor, via AGGR_INIT_ZERO_FIRST (c++/68006). */
16520 && !implicit_default_ctor_p (decl1))
16521 finish_expr_stmt (build_clobber_this ());
16522
16523 if (!processing_template_decl
16524 && DECL_CONSTRUCTOR_P (decl1)
16525 && sanitize_flags_p (SANITIZE_VPTR)
16526 && !DECL_CLONED_FUNCTION_P (decl1)
16527 && !implicit_default_ctor_p (decl1))
16528 cp_ubsan_maybe_initialize_vtbl_ptrs (current_class_ptr);
16529
16530 if (!DECL_OMP_DECLARE_REDUCTION_P (decl1))
16531 start_lambda_scope (decl1);
16532
16533 return true;
16534 }
16535
16536
16537 /* Like start_preparsed_function, except that instead of a
16538 FUNCTION_DECL, this function takes DECLSPECS and DECLARATOR.
16539
16540 Returns true on success. If the DECLARATOR is not suitable
16541 for a function, we return false, which tells the parser to
16542 skip the entire function. */
16543
16544 bool
start_function(cp_decl_specifier_seq * declspecs,const cp_declarator * declarator,tree attrs)16545 start_function (cp_decl_specifier_seq *declspecs,
16546 const cp_declarator *declarator,
16547 tree attrs)
16548 {
16549 tree decl1;
16550
16551 decl1 = grokdeclarator (declarator, declspecs, FUNCDEF, 1, &attrs);
16552 invoke_plugin_callbacks (PLUGIN_START_PARSE_FUNCTION, decl1);
16553 if (decl1 == error_mark_node)
16554 return false;
16555
16556 if (DECL_MAIN_P (decl1))
16557 /* main must return int. grokfndecl should have corrected it
16558 (and issued a diagnostic) if the user got it wrong. */
16559 gcc_assert (same_type_p (TREE_TYPE (TREE_TYPE (decl1)),
16560 integer_type_node));
16561
16562 return start_preparsed_function (decl1, attrs, /*flags=*/SF_DEFAULT);
16563 }
16564
16565 /* Returns true iff an EH_SPEC_BLOCK should be created in the body of
16566 FN. */
16567
16568 static bool
use_eh_spec_block(tree fn)16569 use_eh_spec_block (tree fn)
16570 {
16571 return (flag_exceptions && flag_enforce_eh_specs
16572 && !processing_template_decl
16573 /* We insert the EH_SPEC_BLOCK only in the original
16574 function; then, it is copied automatically to the
16575 clones. */
16576 && !DECL_CLONED_FUNCTION_P (fn)
16577 /* Implicitly-generated constructors and destructors have
16578 exception specifications. However, those specifications
16579 are the union of the possible exceptions specified by the
16580 constructors/destructors for bases and members, so no
16581 unallowed exception will ever reach this function. By
16582 not creating the EH_SPEC_BLOCK we save a little memory,
16583 and we avoid spurious warnings about unreachable
16584 code. */
16585 && !DECL_DEFAULTED_FN (fn)
16586 && !type_throw_all_p (TREE_TYPE (fn)));
16587 }
16588
16589 /* Helper function to push ARGS into the current lexical scope. DECL
16590 is the function declaration. NONPARMS is used to handle enum
16591 constants. */
16592
16593 void
do_push_parm_decls(tree decl,tree args,tree * nonparms)16594 do_push_parm_decls (tree decl, tree args, tree *nonparms)
16595 {
16596 /* If we're doing semantic analysis, then we'll call pushdecl
16597 for each of these. We must do them in reverse order so that
16598 they end in the correct forward order. */
16599 args = nreverse (args);
16600
16601 tree next;
16602 for (tree parm = args; parm; parm = next)
16603 {
16604 next = DECL_CHAIN (parm);
16605 if (TREE_CODE (parm) == PARM_DECL)
16606 pushdecl (parm);
16607 else if (nonparms)
16608 {
16609 /* If we find an enum constant or a type tag, put it aside for
16610 the moment. */
16611 TREE_CHAIN (parm) = NULL_TREE;
16612 *nonparms = chainon (*nonparms, parm);
16613 }
16614 }
16615
16616 /* Get the decls in their original chain order and record in the
16617 function. This is all and only the PARM_DECLs that were
16618 pushed into scope by the loop above. */
16619 DECL_ARGUMENTS (decl) = get_local_decls ();
16620 }
16621
16622 /* Store the parameter declarations into the current function declaration.
16623 This is called after parsing the parameter declarations, before
16624 digesting the body of the function.
16625
16626 Also install to binding contour return value identifier, if any. */
16627
16628 static void
store_parm_decls(tree current_function_parms)16629 store_parm_decls (tree current_function_parms)
16630 {
16631 tree fndecl = current_function_decl;
16632
16633 /* This is a chain of any other decls that came in among the parm
16634 declarations. If a parm is declared with enum {foo, bar} x;
16635 then CONST_DECLs for foo and bar are put here. */
16636 tree nonparms = NULL_TREE;
16637
16638 if (current_function_parms)
16639 {
16640 /* This case is when the function was defined with an ANSI prototype.
16641 The parms already have decls, so we need not do anything here
16642 except record them as in effect
16643 and complain if any redundant old-style parm decls were written. */
16644
16645 tree specparms = current_function_parms;
16646
16647 /* Must clear this because it might contain TYPE_DECLs declared
16648 at class level. */
16649 current_binding_level->names = NULL;
16650
16651 do_push_parm_decls (fndecl, specparms, &nonparms);
16652 }
16653 else
16654 DECL_ARGUMENTS (fndecl) = NULL_TREE;
16655
16656 /* Now store the final chain of decls for the arguments
16657 as the decl-chain of the current lexical scope.
16658 Put the enumerators in as well, at the front so that
16659 DECL_ARGUMENTS is not modified. */
16660 current_binding_level->names = chainon (nonparms, DECL_ARGUMENTS (fndecl));
16661
16662 if (use_eh_spec_block (current_function_decl))
16663 current_eh_spec_block = begin_eh_spec_block ();
16664 }
16665
16666
16667 /* Set the return value of the constructor (if present). */
16668
16669 static void
finish_constructor_body(void)16670 finish_constructor_body (void)
16671 {
16672 tree val;
16673 tree exprstmt;
16674
16675 if (targetm.cxx.cdtor_returns_this ())
16676 {
16677 /* Any return from a constructor will end up here. */
16678 add_stmt (build_stmt (input_location, LABEL_EXPR, cdtor_label));
16679
16680 val = DECL_ARGUMENTS (current_function_decl);
16681 val = build2 (MODIFY_EXPR, TREE_TYPE (val),
16682 DECL_RESULT (current_function_decl), val);
16683 /* Return the address of the object. */
16684 exprstmt = build_stmt (input_location, RETURN_EXPR, val);
16685 add_stmt (exprstmt);
16686 }
16687 }
16688
16689 /* Do all the processing for the beginning of a destructor; set up the
16690 vtable pointers and cleanups for bases and members. */
16691
16692 static void
begin_destructor_body(void)16693 begin_destructor_body (void)
16694 {
16695 tree compound_stmt;
16696
16697 /* If the CURRENT_CLASS_TYPE is incomplete, we will have already
16698 issued an error message. We still want to try to process the
16699 body of the function, but initialize_vtbl_ptrs will crash if
16700 TYPE_BINFO is NULL. */
16701 if (COMPLETE_TYPE_P (current_class_type))
16702 {
16703 compound_stmt = begin_compound_stmt (0);
16704 /* Make all virtual function table pointers in non-virtual base
16705 classes point to CURRENT_CLASS_TYPE's virtual function
16706 tables. */
16707 initialize_vtbl_ptrs (current_class_ptr);
16708 finish_compound_stmt (compound_stmt);
16709
16710 if (flag_lifetime_dse
16711 /* Clobbering an empty base is harmful if it overlays real data. */
16712 && !is_empty_class (current_class_type))
16713 {
16714 if (sanitize_flags_p (SANITIZE_VPTR)
16715 && (flag_sanitize_recover & SANITIZE_VPTR) == 0
16716 && TYPE_CONTAINS_VPTR_P (current_class_type))
16717 {
16718 tree binfo = TYPE_BINFO (current_class_type);
16719 tree ref
16720 = cp_build_fold_indirect_ref (current_class_ptr);
16721
16722 tree vtbl_ptr = build_vfield_ref (ref, TREE_TYPE (binfo));
16723 tree vtbl = build_zero_cst (TREE_TYPE (vtbl_ptr));
16724 tree stmt = cp_build_modify_expr (input_location, vtbl_ptr,
16725 NOP_EXPR, vtbl,
16726 tf_warning_or_error);
16727 /* If the vptr is shared with some virtual nearly empty base,
16728 don't clear it if not in charge, the dtor of the virtual
16729 nearly empty base will do that later. */
16730 if (CLASSTYPE_VBASECLASSES (current_class_type))
16731 {
16732 tree c = current_class_type;
16733 while (CLASSTYPE_PRIMARY_BINFO (c))
16734 {
16735 if (BINFO_VIRTUAL_P (CLASSTYPE_PRIMARY_BINFO (c)))
16736 {
16737 stmt = convert_to_void (stmt, ICV_STATEMENT,
16738 tf_warning_or_error);
16739 stmt = build_if_in_charge (stmt);
16740 break;
16741 }
16742 c = BINFO_TYPE (CLASSTYPE_PRIMARY_BINFO (c));
16743 }
16744 }
16745 finish_decl_cleanup (NULL_TREE, stmt);
16746 }
16747 else
16748 finish_decl_cleanup (NULL_TREE, build_clobber_this ());
16749 }
16750
16751 /* And insert cleanups for our bases and members so that they
16752 will be properly destroyed if we throw. */
16753 push_base_cleanups ();
16754 }
16755 }
16756
16757 /* At the end of every destructor we generate code to delete the object if
16758 necessary. Do that now. */
16759
16760 static void
finish_destructor_body(void)16761 finish_destructor_body (void)
16762 {
16763 tree exprstmt;
16764
16765 /* Any return from a destructor will end up here; that way all base
16766 and member cleanups will be run when the function returns. */
16767 add_stmt (build_stmt (input_location, LABEL_EXPR, cdtor_label));
16768
16769 if (targetm.cxx.cdtor_returns_this ())
16770 {
16771 tree val;
16772
16773 val = DECL_ARGUMENTS (current_function_decl);
16774 val = build2 (MODIFY_EXPR, TREE_TYPE (val),
16775 DECL_RESULT (current_function_decl), val);
16776 /* Return the address of the object. */
16777 exprstmt = build_stmt (input_location, RETURN_EXPR, val);
16778 add_stmt (exprstmt);
16779 }
16780 }
16781
16782 /* Do the necessary processing for the beginning of a function body, which
16783 in this case includes member-initializers, but not the catch clauses of
16784 a function-try-block. Currently, this means opening a binding level
16785 for the member-initializers (in a ctor), member cleanups (in a dtor),
16786 and capture proxies (in a lambda operator()). */
16787
16788 tree
begin_function_body(void)16789 begin_function_body (void)
16790 {
16791 tree stmt;
16792
16793 if (! FUNCTION_NEEDS_BODY_BLOCK (current_function_decl))
16794 return NULL_TREE;
16795
16796 if (processing_template_decl)
16797 /* Do nothing now. */;
16798 else
16799 /* Always keep the BLOCK node associated with the outermost pair of
16800 curly braces of a function. These are needed for correct
16801 operation of dwarfout.c. */
16802 keep_next_level (true);
16803
16804 stmt = begin_compound_stmt (BCS_FN_BODY);
16805
16806 if (processing_template_decl)
16807 /* Do nothing now. */;
16808 else if (DECL_DESTRUCTOR_P (current_function_decl))
16809 begin_destructor_body ();
16810
16811 return stmt;
16812 }
16813
16814 /* Do the processing for the end of a function body. Currently, this means
16815 closing out the cleanups for fully-constructed bases and members, and in
16816 the case of the destructor, deleting the object if desired. Again, this
16817 is only meaningful for [cd]tors, since they are the only functions where
16818 there is a significant distinction between the main body and any
16819 function catch clauses. Handling, say, main() return semantics here
16820 would be wrong, as flowing off the end of a function catch clause for
16821 main() would also need to return 0. */
16822
16823 void
finish_function_body(tree compstmt)16824 finish_function_body (tree compstmt)
16825 {
16826 if (compstmt == NULL_TREE)
16827 return;
16828
16829 /* Close the block. */
16830 finish_compound_stmt (compstmt);
16831
16832 if (processing_template_decl)
16833 /* Do nothing now. */;
16834 else if (DECL_CONSTRUCTOR_P (current_function_decl))
16835 finish_constructor_body ();
16836 else if (DECL_DESTRUCTOR_P (current_function_decl))
16837 finish_destructor_body ();
16838 }
16839
16840 /* Given a function, returns the BLOCK corresponding to the outermost level
16841 of curly braces, skipping the artificial block created for constructor
16842 initializers. */
16843
16844 tree
outer_curly_brace_block(tree fndecl)16845 outer_curly_brace_block (tree fndecl)
16846 {
16847 tree block = DECL_INITIAL (fndecl);
16848 if (BLOCK_OUTER_CURLY_BRACE_P (block))
16849 return block;
16850 block = BLOCK_SUBBLOCKS (block);
16851 if (BLOCK_OUTER_CURLY_BRACE_P (block))
16852 return block;
16853 block = BLOCK_SUBBLOCKS (block);
16854 gcc_assert (BLOCK_OUTER_CURLY_BRACE_P (block));
16855 return block;
16856 }
16857
16858 /* If FNDECL is a class's key method, add the class to the list of
16859 keyed classes that should be emitted. */
16860
16861 static void
record_key_method_defined(tree fndecl)16862 record_key_method_defined (tree fndecl)
16863 {
16864 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fndecl)
16865 && DECL_VIRTUAL_P (fndecl)
16866 && !processing_template_decl)
16867 {
16868 tree fnclass = DECL_CONTEXT (fndecl);
16869 if (fndecl == CLASSTYPE_KEY_METHOD (fnclass))
16870 vec_safe_push (keyed_classes, fnclass);
16871 }
16872 }
16873
16874 /* Subroutine of finish_function.
16875 Save the body of constexpr functions for possible
16876 future compile time evaluation. */
16877
16878 static void
maybe_save_function_definition(tree fun)16879 maybe_save_function_definition (tree fun)
16880 {
16881 if (!processing_template_decl
16882 && DECL_DECLARED_CONSTEXPR_P (fun)
16883 && !cp_function_chain->invalid_constexpr
16884 && !DECL_CLONED_FUNCTION_P (fun))
16885 register_constexpr_fundef (fun, DECL_SAVED_TREE (fun));
16886 }
16887
16888 /* Attempt to add a fix-it hint to RICHLOC suggesting the insertion
16889 of "return *this;" immediately before its location, using FNDECL's
16890 first statement (if any) to give the indentation, if appropriate. */
16891
16892 static void
add_return_star_this_fixit(gcc_rich_location * richloc,tree fndecl)16893 add_return_star_this_fixit (gcc_rich_location *richloc, tree fndecl)
16894 {
16895 location_t indent = UNKNOWN_LOCATION;
16896 tree stmts = expr_first (DECL_SAVED_TREE (fndecl));
16897 if (stmts)
16898 indent = EXPR_LOCATION (stmts);
16899 richloc->add_fixit_insert_formatted ("return *this;",
16900 richloc->get_loc (),
16901 indent);
16902 }
16903
16904 /* This function carries out the subset of finish_function operations needed
16905 to emit the compiler-generated outlined helper functions used by the
16906 coroutines implementation. */
16907
16908 static void
emit_coro_helper(tree helper)16909 emit_coro_helper (tree helper)
16910 {
16911 /* This is a partial set of the operations done by finish_function()
16912 plus emitting the result. */
16913 set_cfun (NULL);
16914 current_function_decl = helper;
16915 begin_scope (sk_function_parms, NULL);
16916 store_parm_decls (DECL_ARGUMENTS (helper));
16917 announce_function (helper);
16918 allocate_struct_function (helper, false);
16919 cfun->language = ggc_cleared_alloc<language_function> ();
16920 poplevel (1, 0, 1);
16921 maybe_save_function_definition (helper);
16922 /* We must start each function with a clear fold cache. */
16923 clear_fold_cache ();
16924 cp_fold_function (helper);
16925 DECL_CONTEXT (DECL_RESULT (helper)) = helper;
16926 BLOCK_SUPERCONTEXT (DECL_INITIAL (helper)) = helper;
16927 /* This function has coroutine IFNs that we should handle in middle
16928 end lowering. */
16929 cfun->coroutine_component = true;
16930 cp_genericize (helper);
16931 expand_or_defer_fn (helper);
16932 }
16933
16934 /* Finish up a function declaration and compile that function
16935 all the way to assembler language output. The free the storage
16936 for the function definition. INLINE_P is TRUE if we just
16937 finished processing the body of an in-class inline function
16938 definition. (This processing will have taken place after the
16939 class definition is complete.) */
16940
16941 tree
finish_function(bool inline_p)16942 finish_function (bool inline_p)
16943 {
16944 tree fndecl = current_function_decl;
16945 tree fntype, ctype = NULL_TREE;
16946 tree resumer = NULL_TREE, destroyer = NULL_TREE;
16947 bool coro_p = flag_coroutines
16948 && !processing_template_decl
16949 && DECL_COROUTINE_P (fndecl);
16950 bool coro_emit_helpers = false;
16951
16952 /* When we get some parse errors, we can end up without a
16953 current_function_decl, so cope. */
16954 if (fndecl == NULL_TREE)
16955 return error_mark_node;
16956
16957 if (!DECL_OMP_DECLARE_REDUCTION_P (fndecl))
16958 finish_lambda_scope ();
16959
16960 if (c_dialect_objc ())
16961 objc_finish_function ();
16962
16963 record_key_method_defined (fndecl);
16964
16965 fntype = TREE_TYPE (fndecl);
16966
16967 /* TREE_READONLY (fndecl) = 1;
16968 This caused &foo to be of type ptr-to-const-function
16969 which then got a warning when stored in a ptr-to-function variable. */
16970
16971 gcc_assert (building_stmt_list_p ());
16972 /* The current function is being defined, so its DECL_INITIAL should
16973 be set, and unless there's a multiple definition, it should be
16974 error_mark_node. */
16975 gcc_assert (DECL_INITIAL (fndecl) == error_mark_node);
16976
16977 if (coro_p)
16978 {
16979 /* Only try to emit the coroutine outlined helper functions if the
16980 transforms succeeded. Otherwise, treat errors in the same way as
16981 a regular function. */
16982 coro_emit_helpers = morph_fn_to_coro (fndecl, &resumer, &destroyer);
16983
16984 /* We should handle coroutine IFNs in middle end lowering. */
16985 cfun->coroutine_component = true;
16986
16987 /* Do not try to process the ramp's EH unless outlining succeeded. */
16988 if (coro_emit_helpers && use_eh_spec_block (fndecl))
16989 finish_eh_spec_block (TYPE_RAISES_EXCEPTIONS
16990 (TREE_TYPE (fndecl)),
16991 current_eh_spec_block);
16992 }
16993 else
16994 /* For a cloned function, we've already got all the code we need;
16995 there's no need to add any extra bits. */
16996 if (!DECL_CLONED_FUNCTION_P (fndecl))
16997 {
16998 /* Make it so that `main' always returns 0 by default. */
16999 if (DECL_MAIN_P (current_function_decl))
17000 finish_return_stmt (integer_zero_node);
17001
17002 if (use_eh_spec_block (current_function_decl))
17003 finish_eh_spec_block (TYPE_RAISES_EXCEPTIONS
17004 (TREE_TYPE (current_function_decl)),
17005 current_eh_spec_block);
17006 }
17007
17008 /* If we're saving up tree structure, tie off the function now. */
17009 DECL_SAVED_TREE (fndecl) = pop_stmt_list (DECL_SAVED_TREE (fndecl));
17010
17011 finish_fname_decls ();
17012
17013 /* If this function can't throw any exceptions, remember that. */
17014 if (!processing_template_decl
17015 && !cp_function_chain->can_throw
17016 && !flag_non_call_exceptions
17017 && !decl_replaceable_p (fndecl))
17018 TREE_NOTHROW (fndecl) = 1;
17019
17020 /* This must come after expand_function_end because cleanups might
17021 have declarations (from inline functions) that need to go into
17022 this function's blocks. */
17023
17024 /* If the current binding level isn't the outermost binding level
17025 for this function, either there is a bug, or we have experienced
17026 syntax errors and the statement tree is malformed. */
17027 if (current_binding_level->kind != sk_function_parms)
17028 {
17029 /* Make sure we have already experienced errors. */
17030 gcc_assert (errorcount);
17031
17032 /* Throw away the broken statement tree and extra binding
17033 levels. */
17034 DECL_SAVED_TREE (fndecl) = alloc_stmt_list ();
17035
17036 while (current_binding_level->kind != sk_function_parms)
17037 {
17038 if (current_binding_level->kind == sk_class)
17039 pop_nested_class ();
17040 else
17041 poplevel (0, 0, 0);
17042 }
17043 }
17044 poplevel (1, 0, 1);
17045
17046 /* Statements should always be full-expressions at the outermost set
17047 of curly braces for a function. */
17048 gcc_assert (stmts_are_full_exprs_p ());
17049
17050 /* If there are no return statements in a function with auto return type,
17051 the return type is void. But if the declared type is something like
17052 auto*, this is an error. */
17053 if (!processing_template_decl && FNDECL_USED_AUTO (fndecl)
17054 && TREE_TYPE (fntype) == DECL_SAVED_AUTO_RETURN_TYPE (fndecl))
17055 {
17056 if (is_auto (DECL_SAVED_AUTO_RETURN_TYPE (fndecl))
17057 && !current_function_returns_value
17058 && !current_function_returns_null)
17059 {
17060 /* We haven't applied return type deduction because we haven't
17061 seen any return statements. Do that now. */
17062 tree node = type_uses_auto (DECL_SAVED_AUTO_RETURN_TYPE (fndecl));
17063 do_auto_deduction (DECL_SAVED_AUTO_RETURN_TYPE (fndecl),
17064 void_node, node, tf_warning_or_error,
17065 adc_return_type);
17066
17067 apply_deduced_return_type (fndecl, void_type_node);
17068 fntype = TREE_TYPE (fndecl);
17069 }
17070 else if (!current_function_returns_value
17071 && !current_function_returns_null)
17072 {
17073 error ("no return statements in function returning %qT",
17074 DECL_SAVED_AUTO_RETURN_TYPE (fndecl));
17075 inform (input_location, "only plain %<auto%> return type can be "
17076 "deduced to %<void%>");
17077 }
17078 }
17079
17080 /* Remember that we were in class scope. */
17081 if (current_class_name)
17082 ctype = current_class_type;
17083
17084 if (DECL_DELETED_FN (fndecl))
17085 {
17086 DECL_INITIAL (fndecl) = error_mark_node;
17087 DECL_SAVED_TREE (fndecl) = NULL_TREE;
17088 goto cleanup;
17089 }
17090
17091 // If this is a concept, check that the definition is reasonable.
17092 if (DECL_DECLARED_CONCEPT_P (fndecl))
17093 check_function_concept (fndecl);
17094
17095 if (flag_openmp)
17096 if (tree attr = lookup_attribute ("omp declare variant base",
17097 DECL_ATTRIBUTES (fndecl)))
17098 omp_declare_variant_finalize (fndecl, attr);
17099
17100 /* Lambda closure members are implicitly constexpr if possible. */
17101 if (cxx_dialect >= cxx17
17102 && LAMBDA_TYPE_P (CP_DECL_CONTEXT (fndecl)))
17103 DECL_DECLARED_CONSTEXPR_P (fndecl)
17104 = ((processing_template_decl
17105 || is_valid_constexpr_fn (fndecl, /*complain*/false))
17106 && potential_constant_expression (DECL_SAVED_TREE (fndecl)));
17107
17108 /* Save constexpr function body before it gets munged by
17109 the NRV transformation. */
17110 maybe_save_function_definition (fndecl);
17111
17112 /* Invoke the pre-genericize plugin before we start munging things. */
17113 if (!processing_template_decl)
17114 invoke_plugin_callbacks (PLUGIN_PRE_GENERICIZE, fndecl);
17115
17116 /* Perform delayed folding before NRV transformation. */
17117 if (!processing_template_decl
17118 && !DECL_IMMEDIATE_FUNCTION_P (fndecl)
17119 && !DECL_OMP_DECLARE_REDUCTION_P (fndecl))
17120 cp_fold_function (fndecl);
17121
17122 /* Set up the named return value optimization, if we can. Candidate
17123 variables are selected in check_return_expr. */
17124 if (current_function_return_value)
17125 {
17126 tree r = current_function_return_value;
17127 tree outer;
17128
17129 if (r != error_mark_node
17130 /* This is only worth doing for fns that return in memory--and
17131 simpler, since we don't have to worry about promoted modes. */
17132 && aggregate_value_p (TREE_TYPE (TREE_TYPE (fndecl)), fndecl)
17133 /* Only allow this for variables declared in the outer scope of
17134 the function so we know that their lifetime always ends with a
17135 return; see g++.dg/opt/nrv6.C. We could be more flexible if
17136 we were to do this optimization in tree-ssa. */
17137 && (outer = outer_curly_brace_block (fndecl))
17138 && chain_member (r, BLOCK_VARS (outer)))
17139 finalize_nrv (&DECL_SAVED_TREE (fndecl), r, DECL_RESULT (fndecl));
17140
17141 current_function_return_value = NULL_TREE;
17142 }
17143
17144 /* Must mark the RESULT_DECL as being in this function. */
17145 DECL_CONTEXT (DECL_RESULT (fndecl)) = fndecl;
17146
17147 /* Set the BLOCK_SUPERCONTEXT of the outermost function scope to point
17148 to the FUNCTION_DECL node itself. */
17149 BLOCK_SUPERCONTEXT (DECL_INITIAL (fndecl)) = fndecl;
17150
17151 /* Complain if there's just no return statement. */
17152 if (warn_return_type
17153 && !VOID_TYPE_P (TREE_TYPE (fntype))
17154 && !dependent_type_p (TREE_TYPE (fntype))
17155 && !current_function_returns_value && !current_function_returns_null
17156 /* Don't complain if we abort or throw. */
17157 && !current_function_returns_abnormally
17158 /* Don't complain if there's an infinite loop. */
17159 && !current_function_infinite_loop
17160 /* Don't complain if we are declared noreturn. */
17161 && !TREE_THIS_VOLATILE (fndecl)
17162 && !DECL_NAME (DECL_RESULT (fndecl))
17163 && !TREE_NO_WARNING (fndecl)
17164 /* Structor return values (if any) are set by the compiler. */
17165 && !DECL_CONSTRUCTOR_P (fndecl)
17166 && !DECL_DESTRUCTOR_P (fndecl)
17167 && targetm.warn_func_return (fndecl))
17168 {
17169 gcc_rich_location richloc (input_location);
17170 /* Potentially add a "return *this;" fix-it hint for
17171 assignment operators. */
17172 if (IDENTIFIER_ASSIGN_OP_P (DECL_NAME (fndecl)))
17173 {
17174 tree valtype = TREE_TYPE (DECL_RESULT (fndecl));
17175 if (TREE_CODE (valtype) == REFERENCE_TYPE
17176 && current_class_ref
17177 && same_type_ignoring_top_level_qualifiers_p
17178 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref))
17179 && global_dc->option_enabled (OPT_Wreturn_type,
17180 global_dc->lang_mask,
17181 global_dc->option_state))
17182 add_return_star_this_fixit (&richloc, fndecl);
17183 }
17184 if (warning_at (&richloc, OPT_Wreturn_type,
17185 "no return statement in function returning non-void"))
17186 TREE_NO_WARNING (fndecl) = 1;
17187 }
17188
17189 /* Store the end of the function, so that we get good line number
17190 info for the epilogue. */
17191 cfun->function_end_locus = input_location;
17192
17193 /* Complain about parameters that are only set, but never otherwise used. */
17194 if (warn_unused_but_set_parameter
17195 && !processing_template_decl
17196 && errorcount == unused_but_set_errorcount
17197 && !DECL_CLONED_FUNCTION_P (fndecl))
17198 {
17199 tree decl;
17200
17201 for (decl = DECL_ARGUMENTS (fndecl);
17202 decl;
17203 decl = DECL_CHAIN (decl))
17204 if (TREE_USED (decl)
17205 && TREE_CODE (decl) == PARM_DECL
17206 && !DECL_READ_P (decl)
17207 && DECL_NAME (decl)
17208 && !DECL_ARTIFICIAL (decl)
17209 && !TREE_NO_WARNING (decl)
17210 && !DECL_IN_SYSTEM_HEADER (decl)
17211 && TREE_TYPE (decl) != error_mark_node
17212 && !TYPE_REF_P (TREE_TYPE (decl))
17213 && (!CLASS_TYPE_P (TREE_TYPE (decl))
17214 || !TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (decl))))
17215 warning_at (DECL_SOURCE_LOCATION (decl),
17216 OPT_Wunused_but_set_parameter,
17217 "parameter %qD set but not used", decl);
17218 unused_but_set_errorcount = errorcount;
17219 }
17220
17221 /* Complain about locally defined typedefs that are not used in this
17222 function. */
17223 maybe_warn_unused_local_typedefs ();
17224
17225 /* Possibly warn about unused parameters. */
17226 if (warn_unused_parameter
17227 && !processing_template_decl
17228 && !DECL_CLONED_FUNCTION_P (fndecl))
17229 do_warn_unused_parameter (fndecl);
17230
17231 /* Genericize before inlining. */
17232 if (!processing_template_decl
17233 && !DECL_IMMEDIATE_FUNCTION_P (fndecl)
17234 && !DECL_OMP_DECLARE_REDUCTION_P (fndecl))
17235 cp_genericize (fndecl);
17236
17237 /* Emit the resumer and destroyer functions now, providing that we have
17238 not encountered some fatal error. */
17239 if (coro_emit_helpers)
17240 {
17241 emit_coro_helper (resumer);
17242 emit_coro_helper (destroyer);
17243 }
17244
17245 cleanup:
17246 /* We're leaving the context of this function, so zap cfun. It's still in
17247 DECL_STRUCT_FUNCTION, and we'll restore it in tree_rest_of_compilation. */
17248 set_cfun (NULL);
17249 current_function_decl = NULL;
17250
17251 /* If this is an in-class inline definition, we may have to pop the
17252 bindings for the template parameters that we added in
17253 maybe_begin_member_template_processing when start_function was
17254 called. */
17255 if (inline_p)
17256 maybe_end_member_template_processing ();
17257
17258 /* Leave the scope of the class. */
17259 if (ctype)
17260 pop_nested_class ();
17261
17262 --function_depth;
17263
17264 /* Clean up. */
17265 current_function_decl = NULL_TREE;
17266
17267 invoke_plugin_callbacks (PLUGIN_FINISH_PARSE_FUNCTION, fndecl);
17268 return fndecl;
17269 }
17270
17271 /* Create the FUNCTION_DECL for a function definition.
17272 DECLSPECS and DECLARATOR are the parts of the declaration;
17273 they describe the return type and the name of the function,
17274 but twisted together in a fashion that parallels the syntax of C.
17275
17276 This function creates a binding context for the function body
17277 as well as setting up the FUNCTION_DECL in current_function_decl.
17278
17279 Returns a FUNCTION_DECL on success.
17280
17281 If the DECLARATOR is not suitable for a function (it defines a datum
17282 instead), we return 0, which tells yyparse to report a parse error.
17283
17284 May return void_type_node indicating that this method is actually
17285 a friend. See grokfield for more details.
17286
17287 Came here with a `.pushlevel' .
17288
17289 DO NOT MAKE ANY CHANGES TO THIS CODE WITHOUT MAKING CORRESPONDING
17290 CHANGES TO CODE IN `grokfield'. */
17291
17292 tree
grokmethod(cp_decl_specifier_seq * declspecs,const cp_declarator * declarator,tree attrlist)17293 grokmethod (cp_decl_specifier_seq *declspecs,
17294 const cp_declarator *declarator, tree attrlist)
17295 {
17296 tree fndecl = grokdeclarator (declarator, declspecs, MEMFUNCDEF, 0,
17297 &attrlist);
17298
17299 if (fndecl == error_mark_node)
17300 return error_mark_node;
17301
17302 if (attrlist)
17303 cplus_decl_attributes (&fndecl, attrlist, 0);
17304
17305 /* Pass friends other than inline friend functions back. */
17306 if (fndecl == void_type_node)
17307 return fndecl;
17308
17309 if (DECL_IN_AGGR_P (fndecl))
17310 {
17311 if (DECL_CLASS_SCOPE_P (fndecl))
17312 error ("%qD is already defined in class %qT", fndecl,
17313 DECL_CONTEXT (fndecl));
17314 return error_mark_node;
17315 }
17316
17317 check_template_shadow (fndecl);
17318
17319 if (TREE_PUBLIC (fndecl))
17320 DECL_COMDAT (fndecl) = 1;
17321 DECL_DECLARED_INLINE_P (fndecl) = 1;
17322 DECL_NO_INLINE_WARNING_P (fndecl) = 1;
17323
17324 /* We process method specializations in finish_struct_1. */
17325 if (processing_template_decl && !DECL_TEMPLATE_SPECIALIZATION (fndecl))
17326 {
17327 fndecl = push_template_decl (fndecl);
17328 if (fndecl == error_mark_node)
17329 return fndecl;
17330 }
17331
17332 if (! DECL_FRIEND_P (fndecl))
17333 {
17334 if (DECL_CHAIN (fndecl))
17335 {
17336 fndecl = copy_node (fndecl);
17337 TREE_CHAIN (fndecl) = NULL_TREE;
17338 }
17339 }
17340
17341 cp_finish_decl (fndecl, NULL_TREE, false, NULL_TREE, 0);
17342
17343 DECL_IN_AGGR_P (fndecl) = 1;
17344 return fndecl;
17345 }
17346
17347
17348 /* VAR is a VAR_DECL. If its type is incomplete, remember VAR so that
17349 we can lay it out later, when and if its type becomes complete.
17350
17351 Also handle constexpr variables where the initializer involves
17352 an unlowered PTRMEM_CST because the class isn't complete yet. */
17353
17354 void
maybe_register_incomplete_var(tree var)17355 maybe_register_incomplete_var (tree var)
17356 {
17357 gcc_assert (VAR_P (var));
17358
17359 /* Keep track of variables with incomplete types. */
17360 if (!processing_template_decl && TREE_TYPE (var) != error_mark_node
17361 && DECL_EXTERNAL (var))
17362 {
17363 tree inner_type = TREE_TYPE (var);
17364
17365 while (TREE_CODE (inner_type) == ARRAY_TYPE)
17366 inner_type = TREE_TYPE (inner_type);
17367 inner_type = TYPE_MAIN_VARIANT (inner_type);
17368
17369 if ((!COMPLETE_TYPE_P (inner_type) && CLASS_TYPE_P (inner_type))
17370 /* RTTI TD entries are created while defining the type_info. */
17371 || (TYPE_LANG_SPECIFIC (inner_type)
17372 && TYPE_BEING_DEFINED (inner_type)))
17373 {
17374 incomplete_var iv = {var, inner_type};
17375 vec_safe_push (incomplete_vars, iv);
17376 }
17377 else if (!(DECL_LANG_SPECIFIC (var) && DECL_TEMPLATE_INFO (var))
17378 && decl_constant_var_p (var)
17379 && (TYPE_PTRMEM_P (inner_type) || CLASS_TYPE_P (inner_type)))
17380 {
17381 /* When the outermost open class is complete we can resolve any
17382 pointers-to-members. */
17383 tree context = outermost_open_class ();
17384 incomplete_var iv = {var, context};
17385 vec_safe_push (incomplete_vars, iv);
17386 }
17387 }
17388 }
17389
17390 /* Called when a class type (given by TYPE) is defined. If there are
17391 any existing VAR_DECLs whose type has been completed by this
17392 declaration, update them now. */
17393
17394 void
complete_vars(tree type)17395 complete_vars (tree type)
17396 {
17397 unsigned ix;
17398 incomplete_var *iv;
17399
17400 for (ix = 0; vec_safe_iterate (incomplete_vars, ix, &iv); )
17401 {
17402 if (same_type_p (type, iv->incomplete_type))
17403 {
17404 tree var = iv->decl;
17405 tree type = TREE_TYPE (var);
17406
17407 if (type != error_mark_node
17408 && (TYPE_MAIN_VARIANT (strip_array_types (type))
17409 == iv->incomplete_type))
17410 {
17411 /* Complete the type of the variable. The VAR_DECL itself
17412 will be laid out in expand_expr. */
17413 complete_type (type);
17414 cp_apply_type_quals_to_decl (cp_type_quals (type), var);
17415 }
17416
17417 /* Remove this entry from the list. */
17418 incomplete_vars->unordered_remove (ix);
17419 }
17420 else
17421 ix++;
17422 }
17423
17424 /* Check for pending declarations which may have abstract type. */
17425 complete_type_check_abstract (type);
17426 }
17427
17428 /* If DECL is of a type which needs a cleanup, build and return an
17429 expression to perform that cleanup here. Return NULL_TREE if no
17430 cleanup need be done. DECL can also be a _REF when called from
17431 split_nonconstant_init_1. */
17432
17433 tree
cxx_maybe_build_cleanup(tree decl,tsubst_flags_t complain)17434 cxx_maybe_build_cleanup (tree decl, tsubst_flags_t complain)
17435 {
17436 tree type;
17437 tree attr;
17438 tree cleanup;
17439
17440 /* Assume no cleanup is required. */
17441 cleanup = NULL_TREE;
17442
17443 if (error_operand_p (decl))
17444 return cleanup;
17445
17446 /* Handle "__attribute__((cleanup))". We run the cleanup function
17447 before the destructor since the destructor is what actually
17448 terminates the lifetime of the object. */
17449 if (DECL_P (decl))
17450 attr = lookup_attribute ("cleanup", DECL_ATTRIBUTES (decl));
17451 else
17452 attr = NULL_TREE;
17453 if (attr)
17454 {
17455 tree id;
17456 tree fn;
17457 tree arg;
17458
17459 /* Get the name specified by the user for the cleanup function. */
17460 id = TREE_VALUE (TREE_VALUE (attr));
17461 /* Look up the name to find the cleanup function to call. It is
17462 important to use lookup_name here because that is what is
17463 used in c-common.c:handle_cleanup_attribute when performing
17464 initial checks on the attribute. Note that those checks
17465 include ensuring that the function found is not an overloaded
17466 function, or an object with an overloaded call operator,
17467 etc.; we can rely on the fact that the function found is an
17468 ordinary FUNCTION_DECL. */
17469 fn = lookup_name (id);
17470 arg = build_address (decl);
17471 if (!mark_used (decl, complain) && !(complain & tf_error))
17472 return error_mark_node;
17473 cleanup = cp_build_function_call_nary (fn, complain, arg, NULL_TREE);
17474 if (cleanup == error_mark_node)
17475 return error_mark_node;
17476 }
17477 /* Handle ordinary C++ destructors. */
17478 type = TREE_TYPE (decl);
17479 if (type_build_dtor_call (type))
17480 {
17481 int flags = LOOKUP_NORMAL|LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR;
17482 tree addr;
17483 tree call;
17484
17485 if (TREE_CODE (type) == ARRAY_TYPE)
17486 addr = decl;
17487 else
17488 addr = build_address (decl);
17489
17490 call = build_delete (input_location, TREE_TYPE (addr), addr,
17491 sfk_complete_destructor, flags, 0, complain);
17492 if (call == error_mark_node)
17493 cleanup = error_mark_node;
17494 else if (TYPE_HAS_TRIVIAL_DESTRUCTOR (type))
17495 /* Discard the call. */;
17496 else if (decl_maybe_constant_destruction (decl, type)
17497 && DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
17498 cxx_constant_dtor (call, decl);
17499 else if (cleanup)
17500 cleanup = cp_build_compound_expr (cleanup, call, complain);
17501 else
17502 cleanup = call;
17503 }
17504
17505 /* build_delete sets the location of the destructor call to the
17506 current location, even though the destructor is going to be
17507 called later, at the end of the current scope. This can lead to
17508 a "jumpy" behavior for users of debuggers when they step around
17509 the end of the block. So let's unset the location of the
17510 destructor call instead. */
17511 protected_set_expr_location (cleanup, UNKNOWN_LOCATION);
17512 if (cleanup && CONVERT_EXPR_P (cleanup))
17513 protected_set_expr_location (TREE_OPERAND (cleanup, 0), UNKNOWN_LOCATION);
17514
17515 if (cleanup
17516 && DECL_P (decl)
17517 && !lookup_attribute ("warn_unused", TYPE_ATTRIBUTES (TREE_TYPE (decl)))
17518 /* Treat objects with destructors as used; the destructor may do
17519 something substantive. */
17520 && !mark_used (decl, complain) && !(complain & tf_error))
17521 return error_mark_node;
17522
17523 if (cleanup && cfun && !processing_template_decl
17524 && !expr_noexcept_p (cleanup, tf_none))
17525 cp_function_chain->throwing_cleanup = true;
17526
17527 return cleanup;
17528 }
17529
17530
17531 /* Return the FUNCTION_TYPE that corresponds to MEMFNTYPE, which can be a
17532 FUNCTION_DECL, METHOD_TYPE, FUNCTION_TYPE, pointer or reference to
17533 METHOD_TYPE or FUNCTION_TYPE, or pointer to member function. */
17534
17535 tree
static_fn_type(tree memfntype)17536 static_fn_type (tree memfntype)
17537 {
17538 tree fntype;
17539 tree args;
17540
17541 if (TYPE_PTRMEMFUNC_P (memfntype))
17542 memfntype = TYPE_PTRMEMFUNC_FN_TYPE (memfntype);
17543 if (INDIRECT_TYPE_P (memfntype)
17544 || TREE_CODE (memfntype) == FUNCTION_DECL)
17545 memfntype = TREE_TYPE (memfntype);
17546 if (TREE_CODE (memfntype) == FUNCTION_TYPE)
17547 return memfntype;
17548 gcc_assert (TREE_CODE (memfntype) == METHOD_TYPE);
17549 args = TYPE_ARG_TYPES (memfntype);
17550 fntype = build_function_type (TREE_TYPE (memfntype), TREE_CHAIN (args));
17551 fntype = apply_memfn_quals (fntype, type_memfn_quals (memfntype));
17552 fntype = (cp_build_type_attribute_variant
17553 (fntype, TYPE_ATTRIBUTES (memfntype)));
17554 fntype = cxx_copy_lang_qualifiers (fntype, memfntype);
17555 return fntype;
17556 }
17557
17558 /* DECL was originally constructed as a non-static member function,
17559 but turned out to be static. Update it accordingly. */
17560
17561 void
revert_static_member_fn(tree decl)17562 revert_static_member_fn (tree decl)
17563 {
17564 tree stype = static_fn_type (decl);
17565 cp_cv_quals quals = type_memfn_quals (stype);
17566 cp_ref_qualifier rqual = type_memfn_rqual (stype);
17567
17568 if (quals != TYPE_UNQUALIFIED || rqual != REF_QUAL_NONE)
17569 stype = apply_memfn_quals (stype, TYPE_UNQUALIFIED, REF_QUAL_NONE);
17570
17571 TREE_TYPE (decl) = stype;
17572
17573 if (DECL_ARGUMENTS (decl))
17574 DECL_ARGUMENTS (decl) = DECL_CHAIN (DECL_ARGUMENTS (decl));
17575 DECL_STATIC_FUNCTION_P (decl) = 1;
17576 }
17577
17578 /* Return which tree structure is used by T, or TS_CP_GENERIC if T is
17579 one of the language-independent trees. */
17580
17581 enum cp_tree_node_structure_enum
cp_tree_node_structure(union lang_tree_node * t)17582 cp_tree_node_structure (union lang_tree_node * t)
17583 {
17584 switch (TREE_CODE (&t->generic))
17585 {
17586 case ARGUMENT_PACK_SELECT: return TS_CP_ARGUMENT_PACK_SELECT;
17587 case BASELINK: return TS_CP_BASELINK;
17588 case CONSTRAINT_INFO: return TS_CP_CONSTRAINT_INFO;
17589 case DEFERRED_NOEXCEPT: return TS_CP_DEFERRED_NOEXCEPT;
17590 case DEFERRED_PARSE: return TS_CP_DEFERRED_PARSE;
17591 case IDENTIFIER_NODE: return TS_CP_IDENTIFIER;
17592 case LAMBDA_EXPR: return TS_CP_LAMBDA_EXPR;
17593 case OVERLOAD: return TS_CP_OVERLOAD;
17594 case PTRMEM_CST: return TS_CP_PTRMEM;
17595 case STATIC_ASSERT: return TS_CP_STATIC_ASSERT;
17596 case TEMPLATE_DECL: return TS_CP_TEMPLATE_DECL;
17597 case TEMPLATE_INFO: return TS_CP_TEMPLATE_INFO;
17598 case TEMPLATE_PARM_INDEX: return TS_CP_TPI;
17599 case TRAIT_EXPR: return TS_CP_TRAIT_EXPR;
17600 case USERDEF_LITERAL: return TS_CP_USERDEF_LITERAL;
17601 default: return TS_CP_GENERIC;
17602 }
17603 }
17604
17605 /* Build the void_list_node (void_type_node having been created). */
17606 tree
build_void_list_node(void)17607 build_void_list_node (void)
17608 {
17609 tree t = build_tree_list (NULL_TREE, void_type_node);
17610 return t;
17611 }
17612
17613 bool
cp_missing_noreturn_ok_p(tree decl)17614 cp_missing_noreturn_ok_p (tree decl)
17615 {
17616 /* A missing noreturn is ok for the `main' function. */
17617 return DECL_MAIN_P (decl);
17618 }
17619
17620 /* Return the decl used to identify the COMDAT group into which DECL should
17621 be placed. */
17622
17623 tree
cxx_comdat_group(tree decl)17624 cxx_comdat_group (tree decl)
17625 {
17626 /* Virtual tables, construction virtual tables, and virtual table
17627 tables all go in a single COMDAT group, named after the primary
17628 virtual table. */
17629 if (VAR_P (decl) && DECL_VTABLE_OR_VTT_P (decl))
17630 decl = CLASSTYPE_VTABLES (DECL_CONTEXT (decl));
17631 /* For all other DECLs, the COMDAT group is the mangled name of the
17632 declaration itself. */
17633 else
17634 {
17635 while (DECL_THUNK_P (decl))
17636 {
17637 /* If TARGET_USE_LOCAL_THUNK_ALIAS_P, use_thunk puts the thunk
17638 into the same section as the target function. In that case
17639 we must return target's name. */
17640 tree target = THUNK_TARGET (decl);
17641 if (TARGET_USE_LOCAL_THUNK_ALIAS_P (target)
17642 && DECL_SECTION_NAME (target) != NULL
17643 && DECL_ONE_ONLY (target))
17644 decl = target;
17645 else
17646 break;
17647 }
17648 }
17649
17650 return decl;
17651 }
17652
17653 /* Returns the return type for FN as written by the user, which may include
17654 a placeholder for a deduced return type. */
17655
17656 tree
fndecl_declared_return_type(tree fn)17657 fndecl_declared_return_type (tree fn)
17658 {
17659 fn = STRIP_TEMPLATE (fn);
17660 if (FNDECL_USED_AUTO (fn))
17661 return DECL_SAVED_AUTO_RETURN_TYPE (fn);
17662
17663 return TREE_TYPE (TREE_TYPE (fn));
17664 }
17665
17666 /* Returns true iff DECL is a variable or function declared with an auto type
17667 that has not yet been deduced to a real type. */
17668
17669 bool
undeduced_auto_decl(tree decl)17670 undeduced_auto_decl (tree decl)
17671 {
17672 if (cxx_dialect < cxx11)
17673 return false;
17674 STRIP_ANY_LOCATION_WRAPPER (decl);
17675 return ((VAR_OR_FUNCTION_DECL_P (decl)
17676 || TREE_CODE (decl) == TEMPLATE_DECL)
17677 && type_uses_auto (TREE_TYPE (decl)));
17678 }
17679
17680 /* Complain if DECL has an undeduced return type. */
17681
17682 bool
require_deduced_type(tree decl,tsubst_flags_t complain)17683 require_deduced_type (tree decl, tsubst_flags_t complain)
17684 {
17685 if (undeduced_auto_decl (decl))
17686 {
17687 if (TREE_NO_WARNING (decl) && seen_error ())
17688 /* We probably already complained about deduction failure. */;
17689 else if (complain & tf_error)
17690 error ("use of %qD before deduction of %<auto%>", decl);
17691 return false;
17692 }
17693 return true;
17694 }
17695
17696 /* Create a representation of the explicit-specifier with
17697 constant-expression of EXPR. COMPLAIN is as for tsubst. */
17698
17699 tree
build_explicit_specifier(tree expr,tsubst_flags_t complain)17700 build_explicit_specifier (tree expr, tsubst_flags_t complain)
17701 {
17702 if (instantiation_dependent_expression_p (expr))
17703 /* Wait for instantiation, tsubst_function_decl will handle it. */
17704 return expr;
17705
17706 expr = build_converted_constant_bool_expr (expr, complain);
17707 expr = instantiate_non_dependent_expr_sfinae (expr, complain);
17708 expr = cxx_constant_value (expr);
17709 return expr;
17710 }
17711
17712 #include "gt-cp-decl.h"
17713