1 /* Handle initialization things in C++.
2 Copyright (C) 1987-2020 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 /* High-level class interface. */
22
23 #include "config.h"
24 #include "system.h"
25 #include "coretypes.h"
26 #include "target.h"
27 #include "cp-tree.h"
28 #include "stringpool.h"
29 #include "varasm.h"
30 #include "gimplify.h"
31 #include "c-family/c-ubsan.h"
32 #include "intl.h"
33 #include "stringpool.h"
34 #include "attribs.h"
35 #include "asan.h"
36 #include "stor-layout.h"
37
38 static bool begin_init_stmts (tree *, tree *);
39 static tree finish_init_stmts (bool, tree, tree);
40 static void construct_virtual_base (tree, tree);
41 static void expand_aggr_init_1 (tree, tree, tree, tree, int, tsubst_flags_t);
42 static void expand_default_init (tree, tree, tree, tree, int, tsubst_flags_t);
43 static void perform_member_init (tree, tree);
44 static int member_init_ok_or_else (tree, tree, tree);
45 static void expand_virtual_init (tree, tree);
46 static tree sort_mem_initializers (tree, tree);
47 static tree initializing_context (tree);
48 static void expand_cleanup_for_base (tree, tree);
49 static tree dfs_initialize_vtbl_ptrs (tree, void *);
50 static tree build_field_list (tree, tree, int *);
51 static int diagnose_uninitialized_cst_or_ref_member_1 (tree, tree, bool, bool);
52
53 static GTY(()) tree fn;
54
55 /* We are about to generate some complex initialization code.
56 Conceptually, it is all a single expression. However, we may want
57 to include conditionals, loops, and other such statement-level
58 constructs. Therefore, we build the initialization code inside a
59 statement-expression. This function starts such an expression.
60 STMT_EXPR_P and COMPOUND_STMT_P are filled in by this function;
61 pass them back to finish_init_stmts when the expression is
62 complete. */
63
64 static bool
begin_init_stmts(tree * stmt_expr_p,tree * compound_stmt_p)65 begin_init_stmts (tree *stmt_expr_p, tree *compound_stmt_p)
66 {
67 bool is_global = !building_stmt_list_p ();
68
69 *stmt_expr_p = begin_stmt_expr ();
70 *compound_stmt_p = begin_compound_stmt (BCS_NO_SCOPE);
71
72 return is_global;
73 }
74
75 /* Finish out the statement-expression begun by the previous call to
76 begin_init_stmts. Returns the statement-expression itself. */
77
78 static tree
finish_init_stmts(bool is_global,tree stmt_expr,tree compound_stmt)79 finish_init_stmts (bool is_global, tree stmt_expr, tree compound_stmt)
80 {
81 finish_compound_stmt (compound_stmt);
82
83 stmt_expr = finish_stmt_expr (stmt_expr, true);
84
85 gcc_assert (!building_stmt_list_p () == is_global);
86
87 return stmt_expr;
88 }
89
90 /* Constructors */
91
92 /* Called from initialize_vtbl_ptrs via dfs_walk. BINFO is the base
93 which we want to initialize the vtable pointer for, DATA is
94 TREE_LIST whose TREE_VALUE is the this ptr expression. */
95
96 static tree
dfs_initialize_vtbl_ptrs(tree binfo,void * data)97 dfs_initialize_vtbl_ptrs (tree binfo, void *data)
98 {
99 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
100 return dfs_skip_bases;
101
102 if (!BINFO_PRIMARY_P (binfo) || BINFO_VIRTUAL_P (binfo))
103 {
104 tree base_ptr = TREE_VALUE ((tree) data);
105
106 base_ptr = build_base_path (PLUS_EXPR, base_ptr, binfo, /*nonnull=*/1,
107 tf_warning_or_error);
108
109 expand_virtual_init (binfo, base_ptr);
110 }
111
112 return NULL_TREE;
113 }
114
115 /* Initialize all the vtable pointers in the object pointed to by
116 ADDR. */
117
118 void
initialize_vtbl_ptrs(tree addr)119 initialize_vtbl_ptrs (tree addr)
120 {
121 tree list;
122 tree type;
123
124 type = TREE_TYPE (TREE_TYPE (addr));
125 list = build_tree_list (type, addr);
126
127 /* Walk through the hierarchy, initializing the vptr in each base
128 class. We do these in pre-order because we can't find the virtual
129 bases for a class until we've initialized the vtbl for that
130 class. */
131 dfs_walk_once (TYPE_BINFO (type), dfs_initialize_vtbl_ptrs, NULL, list);
132 }
133
134 /* Return an expression for the zero-initialization of an object with
135 type T. This expression will either be a constant (in the case
136 that T is a scalar), or a CONSTRUCTOR (in the case that T is an
137 aggregate), or NULL (in the case that T does not require
138 initialization). In either case, the value can be used as
139 DECL_INITIAL for a decl of the indicated TYPE; it is a valid static
140 initializer. If NELTS is non-NULL, and TYPE is an ARRAY_TYPE, NELTS
141 is the number of elements in the array. If STATIC_STORAGE_P is
142 TRUE, initializers are only generated for entities for which
143 zero-initialization does not simply mean filling the storage with
144 zero bytes. FIELD_SIZE, if non-NULL, is the bit size of the field,
145 subfields with bit positions at or above that bit size shouldn't
146 be added. Note that this only works when the result is assigned
147 to a base COMPONENT_REF; if we only have a pointer to the base subobject,
148 expand_assignment will end up clearing the full size of TYPE. */
149
150 static tree
build_zero_init_1(tree type,tree nelts,bool static_storage_p,tree field_size)151 build_zero_init_1 (tree type, tree nelts, bool static_storage_p,
152 tree field_size)
153 {
154 tree init = NULL_TREE;
155
156 /* [dcl.init]
157
158 To zero-initialize an object of type T means:
159
160 -- if T is a scalar type, the storage is set to the value of zero
161 converted to T.
162
163 -- if T is a non-union class type, the storage for each nonstatic
164 data member and each base-class subobject is zero-initialized.
165
166 -- if T is a union type, the storage for its first data member is
167 zero-initialized.
168
169 -- if T is an array type, the storage for each element is
170 zero-initialized.
171
172 -- if T is a reference type, no initialization is performed. */
173
174 gcc_assert (nelts == NULL_TREE || TREE_CODE (nelts) == INTEGER_CST);
175
176 if (type == error_mark_node)
177 ;
178 else if (static_storage_p && zero_init_p (type))
179 /* In order to save space, we do not explicitly build initializers
180 for items that do not need them. GCC's semantics are that
181 items with static storage duration that are not otherwise
182 initialized are initialized to zero. */
183 ;
184 else if (TYPE_PTR_OR_PTRMEM_P (type))
185 init = fold (convert (type, nullptr_node));
186 else if (NULLPTR_TYPE_P (type))
187 init = build_int_cst (type, 0);
188 else if (SCALAR_TYPE_P (type))
189 init = fold (convert (type, integer_zero_node));
190 else if (RECORD_OR_UNION_CODE_P (TREE_CODE (type)))
191 {
192 tree field;
193 vec<constructor_elt, va_gc> *v = NULL;
194
195 /* Iterate over the fields, building initializations. */
196 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
197 {
198 if (TREE_CODE (field) != FIELD_DECL)
199 continue;
200
201 if (TREE_TYPE (field) == error_mark_node)
202 continue;
203
204 /* Don't add virtual bases for base classes if they are beyond
205 the size of the current field, that means it is present
206 somewhere else in the object. */
207 if (field_size)
208 {
209 tree bitpos = bit_position (field);
210 if (TREE_CODE (bitpos) == INTEGER_CST
211 && !tree_int_cst_lt (bitpos, field_size))
212 continue;
213 }
214
215 /* Note that for class types there will be FIELD_DECLs
216 corresponding to base classes as well. Thus, iterating
217 over TYPE_FIELDs will result in correct initialization of
218 all of the subobjects. */
219 if (!static_storage_p || !zero_init_p (TREE_TYPE (field)))
220 {
221 tree new_field_size
222 = (DECL_FIELD_IS_BASE (field)
223 && DECL_SIZE (field)
224 && TREE_CODE (DECL_SIZE (field)) == INTEGER_CST)
225 ? DECL_SIZE (field) : NULL_TREE;
226 tree value = build_zero_init_1 (TREE_TYPE (field),
227 /*nelts=*/NULL_TREE,
228 static_storage_p,
229 new_field_size);
230 if (value)
231 CONSTRUCTOR_APPEND_ELT(v, field, value);
232 }
233
234 /* For unions, only the first field is initialized. */
235 if (TREE_CODE (type) == UNION_TYPE)
236 break;
237 }
238
239 /* Build a constructor to contain the initializations. */
240 init = build_constructor (type, v);
241 }
242 else if (TREE_CODE (type) == ARRAY_TYPE)
243 {
244 tree max_index;
245 vec<constructor_elt, va_gc> *v = NULL;
246
247 /* Iterate over the array elements, building initializations. */
248 if (nelts)
249 max_index = fold_build2_loc (input_location, MINUS_EXPR,
250 TREE_TYPE (nelts), nelts,
251 build_one_cst (TREE_TYPE (nelts)));
252 /* Treat flexible array members like [0] arrays. */
253 else if (TYPE_DOMAIN (type) == NULL_TREE)
254 return NULL_TREE;
255 else
256 max_index = array_type_nelts (type);
257
258 /* If we have an error_mark here, we should just return error mark
259 as we don't know the size of the array yet. */
260 if (max_index == error_mark_node)
261 return error_mark_node;
262 gcc_assert (TREE_CODE (max_index) == INTEGER_CST);
263
264 /* A zero-sized array, which is accepted as an extension, will
265 have an upper bound of -1. */
266 if (!integer_minus_onep (max_index))
267 {
268 constructor_elt ce;
269
270 /* If this is a one element array, we just use a regular init. */
271 if (integer_zerop (max_index))
272 ce.index = size_zero_node;
273 else
274 ce.index = build2 (RANGE_EXPR, sizetype, size_zero_node,
275 max_index);
276
277 ce.value = build_zero_init_1 (TREE_TYPE (type), /*nelts=*/NULL_TREE,
278 static_storage_p, NULL_TREE);
279 if (ce.value)
280 {
281 vec_alloc (v, 1);
282 v->quick_push (ce);
283 }
284 }
285
286 /* Build a constructor to contain the initializations. */
287 init = build_constructor (type, v);
288 }
289 else if (VECTOR_TYPE_P (type))
290 init = build_zero_cst (type);
291 else
292 gcc_assert (TYPE_REF_P (type));
293
294 /* In all cases, the initializer is a constant. */
295 if (init)
296 TREE_CONSTANT (init) = 1;
297
298 return init;
299 }
300
301 /* Return an expression for the zero-initialization of an object with
302 type T. This expression will either be a constant (in the case
303 that T is a scalar), or a CONSTRUCTOR (in the case that T is an
304 aggregate), or NULL (in the case that T does not require
305 initialization). In either case, the value can be used as
306 DECL_INITIAL for a decl of the indicated TYPE; it is a valid static
307 initializer. If NELTS is non-NULL, and TYPE is an ARRAY_TYPE, NELTS
308 is the number of elements in the array. If STATIC_STORAGE_P is
309 TRUE, initializers are only generated for entities for which
310 zero-initialization does not simply mean filling the storage with
311 zero bytes. */
312
313 tree
build_zero_init(tree type,tree nelts,bool static_storage_p)314 build_zero_init (tree type, tree nelts, bool static_storage_p)
315 {
316 return build_zero_init_1 (type, nelts, static_storage_p, NULL_TREE);
317 }
318
319 /* Return a suitable initializer for value-initializing an object of type
320 TYPE, as described in [dcl.init]. */
321
322 tree
build_value_init(tree type,tsubst_flags_t complain)323 build_value_init (tree type, tsubst_flags_t complain)
324 {
325 /* [dcl.init]
326
327 To value-initialize an object of type T means:
328
329 - if T is a class type (clause 9) with either no default constructor
330 (12.1) or a default constructor that is user-provided or deleted,
331 then the object is default-initialized;
332
333 - if T is a (possibly cv-qualified) class type without a user-provided
334 or deleted default constructor, then the object is zero-initialized
335 and the semantic constraints for default-initialization are checked,
336 and if T has a non-trivial default constructor, the object is
337 default-initialized;
338
339 - if T is an array type, then each element is value-initialized;
340
341 - otherwise, the object is zero-initialized.
342
343 A program that calls for default-initialization or
344 value-initialization of an entity of reference type is ill-formed. */
345
346 /* The AGGR_INIT_EXPR tweaking below breaks in templates. */
347 gcc_assert (!processing_template_decl
348 || (SCALAR_TYPE_P (type) || TREE_CODE (type) == ARRAY_TYPE));
349
350 if (CLASS_TYPE_P (type) && type_build_ctor_call (type))
351 {
352 tree ctor
353 = build_special_member_call (NULL_TREE, complete_ctor_identifier,
354 NULL, type, LOOKUP_NORMAL, complain);
355 if (ctor == error_mark_node || TREE_CONSTANT (ctor))
356 return ctor;
357 tree fn = NULL_TREE;
358 if (TREE_CODE (ctor) == CALL_EXPR)
359 fn = get_callee_fndecl (ctor);
360 ctor = build_aggr_init_expr (type, ctor);
361 if (fn && user_provided_p (fn))
362 return ctor;
363 else if (TYPE_HAS_COMPLEX_DFLT (type))
364 {
365 /* This is a class that needs constructing, but doesn't have
366 a user-provided constructor. So we need to zero-initialize
367 the object and then call the implicitly defined ctor.
368 This will be handled in simplify_aggr_init_expr. */
369 AGGR_INIT_ZERO_FIRST (ctor) = 1;
370 return ctor;
371 }
372 }
373
374 /* Discard any access checking during subobject initialization;
375 the checks are implied by the call to the ctor which we have
376 verified is OK (cpp0x/defaulted46.C). */
377 push_deferring_access_checks (dk_deferred);
378 tree r = build_value_init_noctor (type, complain);
379 pop_deferring_access_checks ();
380 return r;
381 }
382
383 /* Like build_value_init, but don't call the constructor for TYPE. Used
384 for base initializers. */
385
386 tree
build_value_init_noctor(tree type,tsubst_flags_t complain)387 build_value_init_noctor (tree type, tsubst_flags_t complain)
388 {
389 if (!COMPLETE_TYPE_P (type))
390 {
391 if (complain & tf_error)
392 error ("value-initialization of incomplete type %qT", type);
393 return error_mark_node;
394 }
395 /* FIXME the class and array cases should just use digest_init once it is
396 SFINAE-enabled. */
397 if (CLASS_TYPE_P (type))
398 {
399 gcc_assert (!TYPE_HAS_COMPLEX_DFLT (type)
400 || errorcount != 0);
401
402 if (TREE_CODE (type) != UNION_TYPE)
403 {
404 tree field;
405 vec<constructor_elt, va_gc> *v = NULL;
406
407 /* Iterate over the fields, building initializations. */
408 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
409 {
410 tree ftype, value;
411
412 if (TREE_CODE (field) != FIELD_DECL)
413 continue;
414
415 ftype = TREE_TYPE (field);
416
417 if (ftype == error_mark_node)
418 continue;
419
420 /* Ignore flexible array members for value initialization. */
421 if (TREE_CODE (ftype) == ARRAY_TYPE
422 && !COMPLETE_TYPE_P (ftype)
423 && !TYPE_DOMAIN (ftype)
424 && COMPLETE_TYPE_P (TREE_TYPE (ftype))
425 && (next_initializable_field (DECL_CHAIN (field))
426 == NULL_TREE))
427 continue;
428
429 /* We could skip vfields and fields of types with
430 user-defined constructors, but I think that won't improve
431 performance at all; it should be simpler in general just
432 to zero out the entire object than try to only zero the
433 bits that actually need it. */
434
435 /* Note that for class types there will be FIELD_DECLs
436 corresponding to base classes as well. Thus, iterating
437 over TYPE_FIELDs will result in correct initialization of
438 all of the subobjects. */
439 value = build_value_init (ftype, complain);
440 value = maybe_constant_init (value);
441
442 if (value == error_mark_node)
443 return error_mark_node;
444
445 CONSTRUCTOR_APPEND_ELT(v, field, value);
446
447 /* We shouldn't have gotten here for anything that would need
448 non-trivial initialization, and gimplify_init_ctor_preeval
449 would need to be fixed to allow it. */
450 gcc_assert (TREE_CODE (value) != TARGET_EXPR
451 && TREE_CODE (value) != AGGR_INIT_EXPR);
452 }
453
454 /* Build a constructor to contain the zero- initializations. */
455 return build_constructor (type, v);
456 }
457 }
458 else if (TREE_CODE (type) == ARRAY_TYPE)
459 {
460 vec<constructor_elt, va_gc> *v = NULL;
461
462 /* Iterate over the array elements, building initializations. */
463 tree max_index = array_type_nelts (type);
464
465 /* If we have an error_mark here, we should just return error mark
466 as we don't know the size of the array yet. */
467 if (max_index == error_mark_node)
468 {
469 if (complain & tf_error)
470 error ("cannot value-initialize array of unknown bound %qT",
471 type);
472 return error_mark_node;
473 }
474 gcc_assert (TREE_CODE (max_index) == INTEGER_CST);
475
476 /* A zero-sized array, which is accepted as an extension, will
477 have an upper bound of -1. */
478 if (!tree_int_cst_equal (max_index, integer_minus_one_node))
479 {
480 constructor_elt ce;
481
482 /* If this is a one element array, we just use a regular init. */
483 if (tree_int_cst_equal (size_zero_node, max_index))
484 ce.index = size_zero_node;
485 else
486 ce.index = build2 (RANGE_EXPR, sizetype, size_zero_node, max_index);
487
488 ce.value = build_value_init (TREE_TYPE (type), complain);
489 ce.value = maybe_constant_init (ce.value);
490 if (ce.value == error_mark_node)
491 return error_mark_node;
492
493 vec_alloc (v, 1);
494 v->quick_push (ce);
495
496 /* We shouldn't have gotten here for anything that would need
497 non-trivial initialization, and gimplify_init_ctor_preeval
498 would need to be fixed to allow it. */
499 gcc_assert (TREE_CODE (ce.value) != TARGET_EXPR
500 && TREE_CODE (ce.value) != AGGR_INIT_EXPR);
501 }
502
503 /* Build a constructor to contain the initializations. */
504 return build_constructor (type, v);
505 }
506 else if (TREE_CODE (type) == FUNCTION_TYPE)
507 {
508 if (complain & tf_error)
509 error ("value-initialization of function type %qT", type);
510 return error_mark_node;
511 }
512 else if (TYPE_REF_P (type))
513 {
514 if (complain & tf_error)
515 error ("value-initialization of reference type %qT", type);
516 return error_mark_node;
517 }
518
519 return build_zero_init (type, NULL_TREE, /*static_storage_p=*/false);
520 }
521
522 /* Initialize current class with INIT, a TREE_LIST of
523 arguments for a target constructor. If TREE_LIST is void_type_node,
524 an empty initializer list was given. */
525
526 static void
perform_target_ctor(tree init)527 perform_target_ctor (tree init)
528 {
529 tree decl = current_class_ref;
530 tree type = current_class_type;
531
532 finish_expr_stmt (build_aggr_init (decl, init,
533 LOOKUP_NORMAL|LOOKUP_DELEGATING_CONS,
534 tf_warning_or_error));
535 if (type_build_dtor_call (type))
536 {
537 tree expr = build_delete (input_location,
538 type, decl, sfk_complete_destructor,
539 LOOKUP_NORMAL
540 |LOOKUP_NONVIRTUAL
541 |LOOKUP_DESTRUCTOR,
542 0, tf_warning_or_error);
543 if (expr != error_mark_node
544 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
545 finish_eh_cleanup (expr);
546 }
547 }
548
549 /* Return the non-static data initializer for FIELD_DECL MEMBER. */
550
551 static GTY((cache)) decl_tree_cache_map *nsdmi_inst;
552
553 tree
get_nsdmi(tree member,bool in_ctor,tsubst_flags_t complain)554 get_nsdmi (tree member, bool in_ctor, tsubst_flags_t complain)
555 {
556 tree init;
557 tree save_ccp = current_class_ptr;
558 tree save_ccr = current_class_ref;
559
560 if (DECL_LANG_SPECIFIC (member) && DECL_TEMPLATE_INFO (member))
561 {
562 init = DECL_INITIAL (DECL_TI_TEMPLATE (member));
563 location_t expr_loc
564 = cp_expr_loc_or_loc (init, DECL_SOURCE_LOCATION (member));
565 if (TREE_CODE (init) == DEFERRED_PARSE)
566 /* Unparsed. */;
567 else if (tree *slot = hash_map_safe_get (nsdmi_inst, member))
568 init = *slot;
569 /* Check recursive instantiation. */
570 else if (DECL_INSTANTIATING_NSDMI_P (member))
571 {
572 if (complain & tf_error)
573 error_at (expr_loc, "recursive instantiation of default member "
574 "initializer for %qD", member);
575 init = error_mark_node;
576 }
577 else
578 {
579 cp_evaluated ev;
580
581 location_t sloc = input_location;
582 input_location = expr_loc;
583
584 DECL_INSTANTIATING_NSDMI_P (member) = 1;
585
586 bool pushed = false;
587 tree ctx = DECL_CONTEXT (member);
588 if (!currently_open_class (ctx)
589 && !LOCAL_CLASS_P (ctx))
590 {
591 push_to_top_level ();
592 push_nested_class (ctx);
593 pushed = true;
594 }
595
596 gcc_checking_assert (!processing_template_decl);
597
598 inject_this_parameter (ctx, TYPE_UNQUALIFIED);
599
600 start_lambda_scope (member);
601
602 /* Do deferred instantiation of the NSDMI. */
603 init = (tsubst_copy_and_build
604 (init, DECL_TI_ARGS (member),
605 complain, member, /*function_p=*/false,
606 /*integral_constant_expression_p=*/false));
607 init = digest_nsdmi_init (member, init, complain);
608
609 finish_lambda_scope ();
610
611 DECL_INSTANTIATING_NSDMI_P (member) = 0;
612
613 if (init != error_mark_node)
614 hash_map_safe_put<hm_ggc> (nsdmi_inst, member, init);
615
616 if (pushed)
617 {
618 pop_nested_class ();
619 pop_from_top_level ();
620 }
621
622 input_location = sloc;
623 }
624 }
625 else
626 init = DECL_INITIAL (member);
627
628 if (init && TREE_CODE (init) == DEFERRED_PARSE)
629 {
630 if (complain & tf_error)
631 {
632 error ("default member initializer for %qD required before the end "
633 "of its enclosing class", member);
634 inform (location_of (init), "defined here");
635 DECL_INITIAL (member) = error_mark_node;
636 }
637 init = error_mark_node;
638 }
639
640 if (in_ctor)
641 {
642 current_class_ptr = save_ccp;
643 current_class_ref = save_ccr;
644 }
645 else
646 {
647 /* Use a PLACEHOLDER_EXPR when we don't have a 'this' parameter to
648 refer to; constexpr evaluation knows what to do with it. */
649 current_class_ref = build0 (PLACEHOLDER_EXPR, DECL_CONTEXT (member));
650 current_class_ptr = build_address (current_class_ref);
651 }
652
653 /* Strip redundant TARGET_EXPR so we don't need to remap it, and
654 so the aggregate init code below will see a CONSTRUCTOR. */
655 bool simple_target = (init && SIMPLE_TARGET_EXPR_P (init));
656 if (simple_target)
657 init = TARGET_EXPR_INITIAL (init);
658 init = break_out_target_exprs (init, /*loc*/true);
659 if (in_ctor && init && TREE_CODE (init) == TARGET_EXPR)
660 /* This expresses the full initialization, prevent perform_member_init from
661 calling another constructor (58162). */
662 TARGET_EXPR_DIRECT_INIT_P (init) = true;
663 if (simple_target && TREE_CODE (init) != CONSTRUCTOR)
664 /* Now put it back so C++17 copy elision works. */
665 init = get_target_expr (init);
666
667 current_class_ptr = save_ccp;
668 current_class_ref = save_ccr;
669 return init;
670 }
671
672 /* Diagnose the flexible array MEMBER if its INITializer is non-null
673 and return true if so. Otherwise return false. */
674
675 bool
maybe_reject_flexarray_init(tree member,tree init)676 maybe_reject_flexarray_init (tree member, tree init)
677 {
678 tree type = TREE_TYPE (member);
679
680 if (!init
681 || TREE_CODE (type) != ARRAY_TYPE
682 || TYPE_DOMAIN (type))
683 return false;
684
685 /* Point at the flexible array member declaration if it's initialized
686 in-class, and at the ctor if it's initialized in a ctor member
687 initializer list. */
688 location_t loc;
689 if (DECL_INITIAL (member) == init
690 || !current_function_decl
691 || DECL_DEFAULTED_FN (current_function_decl))
692 loc = DECL_SOURCE_LOCATION (member);
693 else
694 loc = DECL_SOURCE_LOCATION (current_function_decl);
695
696 error_at (loc, "initializer for flexible array member %q#D", member);
697 return true;
698 }
699
700 /* If INIT's value can come from a call to std::initializer_list<T>::begin,
701 return that function. Otherwise, NULL_TREE. */
702
703 static tree
find_list_begin(tree init)704 find_list_begin (tree init)
705 {
706 STRIP_NOPS (init);
707 while (TREE_CODE (init) == COMPOUND_EXPR)
708 init = TREE_OPERAND (init, 1);
709 STRIP_NOPS (init);
710 if (TREE_CODE (init) == COND_EXPR)
711 {
712 tree left = TREE_OPERAND (init, 1);
713 if (!left)
714 left = TREE_OPERAND (init, 0);
715 left = find_list_begin (left);
716 if (left)
717 return left;
718 return find_list_begin (TREE_OPERAND (init, 2));
719 }
720 if (TREE_CODE (init) == CALL_EXPR)
721 if (tree fn = get_callee_fndecl (init))
722 if (id_equal (DECL_NAME (fn), "begin")
723 && is_std_init_list (DECL_CONTEXT (fn)))
724 return fn;
725 return NULL_TREE;
726 }
727
728 /* If INIT initializing MEMBER is copying the address of the underlying array
729 of an initializer_list, warn. */
730
731 static void
maybe_warn_list_ctor(tree member,tree init)732 maybe_warn_list_ctor (tree member, tree init)
733 {
734 tree memtype = TREE_TYPE (member);
735 if (!init || !TYPE_PTR_P (memtype)
736 || !is_list_ctor (current_function_decl))
737 return;
738
739 tree parms = FUNCTION_FIRST_USER_PARMTYPE (current_function_decl);
740 tree initlist = non_reference (TREE_VALUE (parms));
741 tree targs = CLASSTYPE_TI_ARGS (initlist);
742 tree elttype = TREE_VEC_ELT (targs, 0);
743
744 if (!same_type_ignoring_top_level_qualifiers_p
745 (TREE_TYPE (memtype), elttype))
746 return;
747
748 tree begin = find_list_begin (init);
749 if (!begin)
750 return;
751
752 location_t loc = cp_expr_loc_or_input_loc (init);
753 warning_at (loc, OPT_Winit_list_lifetime,
754 "initializing %qD from %qE does not extend the lifetime "
755 "of the underlying array", member, begin);
756 }
757
758 /* Initialize MEMBER, a FIELD_DECL, with INIT, a TREE_LIST of
759 arguments. If TREE_LIST is void_type_node, an empty initializer
760 list was given; if NULL_TREE no initializer was given. */
761
762 static void
perform_member_init(tree member,tree init)763 perform_member_init (tree member, tree init)
764 {
765 tree decl;
766 tree type = TREE_TYPE (member);
767
768 /* Use the non-static data member initializer if there was no
769 mem-initializer for this field. */
770 if (init == NULL_TREE)
771 init = get_nsdmi (member, /*ctor*/true, tf_warning_or_error);
772
773 if (init == error_mark_node)
774 return;
775
776 /* Effective C++ rule 12 requires that all data members be
777 initialized. */
778 if (warn_ecpp && init == NULL_TREE && TREE_CODE (type) != ARRAY_TYPE)
779 warning_at (DECL_SOURCE_LOCATION (current_function_decl), OPT_Weffc__,
780 "%qD should be initialized in the member initialization list",
781 member);
782
783 /* Get an lvalue for the data member. */
784 decl = build_class_member_access_expr (current_class_ref, member,
785 /*access_path=*/NULL_TREE,
786 /*preserve_reference=*/true,
787 tf_warning_or_error);
788 if (decl == error_mark_node)
789 return;
790
791 if (warn_init_self && init && TREE_CODE (init) == TREE_LIST
792 && TREE_CHAIN (init) == NULL_TREE)
793 {
794 tree val = TREE_VALUE (init);
795 /* Handle references. */
796 if (REFERENCE_REF_P (val))
797 val = TREE_OPERAND (val, 0);
798 if (TREE_CODE (val) == COMPONENT_REF && TREE_OPERAND (val, 1) == member
799 && TREE_OPERAND (val, 0) == current_class_ref)
800 warning_at (DECL_SOURCE_LOCATION (current_function_decl),
801 OPT_Winit_self, "%qD is initialized with itself",
802 member);
803 }
804
805 if (array_of_unknown_bound_p (type))
806 {
807 maybe_reject_flexarray_init (member, init);
808 return;
809 }
810
811 if (init && TREE_CODE (init) == TREE_LIST
812 && (DIRECT_LIST_INIT_P (TREE_VALUE (init))
813 /* FIXME C++20 parenthesized aggregate init (PR 92812). */
814 || !(/* cxx_dialect >= cxx2a ? CP_AGGREGATE_TYPE_P (type) */
815 /* : */CLASS_TYPE_P (type))))
816 init = build_x_compound_expr_from_list (init, ELK_MEM_INIT,
817 tf_warning_or_error);
818
819 if (init == void_type_node)
820 {
821 /* mem() means value-initialization. */
822 if (TREE_CODE (type) == ARRAY_TYPE)
823 {
824 init = build_vec_init_expr (type, init, tf_warning_or_error);
825 init = build2 (INIT_EXPR, type, decl, init);
826 finish_expr_stmt (init);
827 }
828 else
829 {
830 tree value = build_value_init (type, tf_warning_or_error);
831 if (value == error_mark_node)
832 return;
833 init = build2 (INIT_EXPR, type, decl, value);
834 finish_expr_stmt (init);
835 }
836 }
837 /* Deal with this here, as we will get confused if we try to call the
838 assignment op for an anonymous union. This can happen in a
839 synthesized copy constructor. */
840 else if (ANON_AGGR_TYPE_P (type))
841 {
842 if (init)
843 {
844 init = build2 (INIT_EXPR, type, decl, TREE_VALUE (init));
845 finish_expr_stmt (init);
846 }
847 }
848 else if (init
849 && (TYPE_REF_P (type)
850 || (TREE_CODE (init) == CONSTRUCTOR
851 && (CP_AGGREGATE_TYPE_P (type)
852 || is_std_init_list (type)))))
853 {
854 /* With references and list-initialization, we need to deal with
855 extending temporary lifetimes. 12.2p5: "A temporary bound to a
856 reference member in a constructor’s ctor-initializer (12.6.2)
857 persists until the constructor exits." */
858 unsigned i; tree t;
859 releasing_vec cleanups;
860 if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (init), type))
861 {
862 if (BRACE_ENCLOSED_INITIALIZER_P (init)
863 && CP_AGGREGATE_TYPE_P (type))
864 init = reshape_init (type, init, tf_warning_or_error);
865 init = digest_init (type, init, tf_warning_or_error);
866 }
867 if (init == error_mark_node)
868 return;
869 if (DECL_SIZE (member) && integer_zerop (DECL_SIZE (member))
870 && !TREE_SIDE_EFFECTS (init))
871 /* Don't add trivial initialization of an empty base/field, as they
872 might not be ordered the way the back-end expects. */
873 return;
874 /* A FIELD_DECL doesn't really have a suitable lifetime, but
875 make_temporary_var_for_ref_to_temp will treat it as automatic and
876 set_up_extended_ref_temp wants to use the decl in a warning. */
877 init = extend_ref_init_temps (member, init, &cleanups);
878 if (TREE_CODE (type) == ARRAY_TYPE
879 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (type)))
880 init = build_vec_init_expr (type, init, tf_warning_or_error);
881 init = build2 (INIT_EXPR, type, decl, init);
882 finish_expr_stmt (init);
883 FOR_EACH_VEC_ELT (*cleanups, i, t)
884 push_cleanup (decl, t, false);
885 }
886 else if (type_build_ctor_call (type)
887 || (init && CLASS_TYPE_P (strip_array_types (type))))
888 {
889 if (TREE_CODE (type) == ARRAY_TYPE)
890 {
891 if (init == NULL_TREE
892 || same_type_ignoring_top_level_qualifiers_p (type,
893 TREE_TYPE (init)))
894 {
895 if (TYPE_DOMAIN (type) && TYPE_MAX_VALUE (TYPE_DOMAIN (type)))
896 {
897 /* Initialize the array only if it's not a flexible
898 array member (i.e., if it has an upper bound). */
899 init = build_vec_init_expr (type, init, tf_warning_or_error);
900 init = build2 (INIT_EXPR, type, decl, init);
901 finish_expr_stmt (init);
902 }
903 }
904 else
905 error ("invalid initializer for array member %q#D", member);
906 }
907 else
908 {
909 int flags = LOOKUP_NORMAL;
910 if (DECL_DEFAULTED_FN (current_function_decl))
911 flags |= LOOKUP_DEFAULTED;
912 if (CP_TYPE_CONST_P (type)
913 && init == NULL_TREE
914 && default_init_uninitialized_part (type))
915 {
916 /* TYPE_NEEDS_CONSTRUCTING can be set just because we have a
917 vtable; still give this diagnostic. */
918 auto_diagnostic_group d;
919 if (permerror (DECL_SOURCE_LOCATION (current_function_decl),
920 "uninitialized const member in %q#T", type))
921 inform (DECL_SOURCE_LOCATION (member),
922 "%q#D should be initialized", member );
923 }
924 finish_expr_stmt (build_aggr_init (decl, init, flags,
925 tf_warning_or_error));
926 }
927 }
928 else
929 {
930 if (init == NULL_TREE)
931 {
932 tree core_type;
933 /* member traversal: note it leaves init NULL */
934 if (TYPE_REF_P (type))
935 {
936 auto_diagnostic_group d;
937 if (permerror (DECL_SOURCE_LOCATION (current_function_decl),
938 "uninitialized reference member in %q#T", type))
939 inform (DECL_SOURCE_LOCATION (member),
940 "%q#D should be initialized", member);
941 }
942 else if (CP_TYPE_CONST_P (type))
943 {
944 auto_diagnostic_group d;
945 if (permerror (DECL_SOURCE_LOCATION (current_function_decl),
946 "uninitialized const member in %q#T", type))
947 inform (DECL_SOURCE_LOCATION (member),
948 "%q#D should be initialized", member );
949 }
950
951 core_type = strip_array_types (type);
952
953 if (CLASS_TYPE_P (core_type)
954 && (CLASSTYPE_READONLY_FIELDS_NEED_INIT (core_type)
955 || CLASSTYPE_REF_FIELDS_NEED_INIT (core_type)))
956 diagnose_uninitialized_cst_or_ref_member (core_type,
957 /*using_new=*/false,
958 /*complain=*/true);
959 }
960
961 maybe_warn_list_ctor (member, init);
962
963 if (init)
964 finish_expr_stmt (cp_build_modify_expr (input_location, decl,
965 INIT_EXPR, init,
966 tf_warning_or_error));
967 }
968
969 if (type_build_dtor_call (type))
970 {
971 tree expr;
972
973 expr = build_class_member_access_expr (current_class_ref, member,
974 /*access_path=*/NULL_TREE,
975 /*preserve_reference=*/false,
976 tf_warning_or_error);
977 expr = build_delete (input_location,
978 type, expr, sfk_complete_destructor,
979 LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR, 0,
980 tf_warning_or_error);
981
982 if (expr != error_mark_node
983 && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
984 finish_eh_cleanup (expr);
985 }
986 }
987
988 /* Returns a TREE_LIST containing (as the TREE_PURPOSE of each node) all
989 the FIELD_DECLs on the TYPE_FIELDS list for T, in reverse order. */
990
991 static tree
build_field_list(tree t,tree list,int * uses_unions_or_anon_p)992 build_field_list (tree t, tree list, int *uses_unions_or_anon_p)
993 {
994 tree fields;
995
996 /* Note whether or not T is a union. */
997 if (TREE_CODE (t) == UNION_TYPE)
998 *uses_unions_or_anon_p = 1;
999
1000 for (fields = TYPE_FIELDS (t); fields; fields = DECL_CHAIN (fields))
1001 {
1002 tree fieldtype;
1003
1004 /* Skip CONST_DECLs for enumeration constants and so forth. */
1005 if (TREE_CODE (fields) != FIELD_DECL || DECL_ARTIFICIAL (fields))
1006 continue;
1007
1008 fieldtype = TREE_TYPE (fields);
1009
1010 /* For an anonymous struct or union, we must recursively
1011 consider the fields of the anonymous type. They can be
1012 directly initialized from the constructor. */
1013 if (ANON_AGGR_TYPE_P (fieldtype))
1014 {
1015 /* Add this field itself. Synthesized copy constructors
1016 initialize the entire aggregate. */
1017 list = tree_cons (fields, NULL_TREE, list);
1018 /* And now add the fields in the anonymous aggregate. */
1019 list = build_field_list (fieldtype, list, uses_unions_or_anon_p);
1020 *uses_unions_or_anon_p = 1;
1021 }
1022 /* Add this field. */
1023 else if (DECL_NAME (fields))
1024 list = tree_cons (fields, NULL_TREE, list);
1025 }
1026
1027 return list;
1028 }
1029
1030 /* Return the innermost aggregate scope for FIELD, whether that is
1031 the enclosing class or an anonymous aggregate within it. */
1032
1033 static tree
innermost_aggr_scope(tree field)1034 innermost_aggr_scope (tree field)
1035 {
1036 if (ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1037 return TREE_TYPE (field);
1038 else
1039 return DECL_CONTEXT (field);
1040 }
1041
1042 /* The MEM_INITS are a TREE_LIST. The TREE_PURPOSE of each list gives
1043 a FIELD_DECL or BINFO in T that needs initialization. The
1044 TREE_VALUE gives the initializer, or list of initializer arguments.
1045
1046 Return a TREE_LIST containing all of the initializations required
1047 for T, in the order in which they should be performed. The output
1048 list has the same format as the input. */
1049
1050 static tree
sort_mem_initializers(tree t,tree mem_inits)1051 sort_mem_initializers (tree t, tree mem_inits)
1052 {
1053 tree init;
1054 tree base, binfo, base_binfo;
1055 tree sorted_inits;
1056 tree next_subobject;
1057 vec<tree, va_gc> *vbases;
1058 int i;
1059 int uses_unions_or_anon_p = 0;
1060
1061 /* Build up a list of initializations. The TREE_PURPOSE of entry
1062 will be the subobject (a FIELD_DECL or BINFO) to initialize. The
1063 TREE_VALUE will be the constructor arguments, or NULL if no
1064 explicit initialization was provided. */
1065 sorted_inits = NULL_TREE;
1066
1067 /* Process the virtual bases. */
1068 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
1069 vec_safe_iterate (vbases, i, &base); i++)
1070 sorted_inits = tree_cons (base, NULL_TREE, sorted_inits);
1071
1072 /* Process the direct bases. */
1073 for (binfo = TYPE_BINFO (t), i = 0;
1074 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
1075 if (!BINFO_VIRTUAL_P (base_binfo))
1076 sorted_inits = tree_cons (base_binfo, NULL_TREE, sorted_inits);
1077
1078 /* Process the non-static data members. */
1079 sorted_inits = build_field_list (t, sorted_inits, &uses_unions_or_anon_p);
1080 /* Reverse the entire list of initializations, so that they are in
1081 the order that they will actually be performed. */
1082 sorted_inits = nreverse (sorted_inits);
1083
1084 /* If the user presented the initializers in an order different from
1085 that in which they will actually occur, we issue a warning. Keep
1086 track of the next subobject which can be explicitly initialized
1087 without issuing a warning. */
1088 next_subobject = sorted_inits;
1089
1090 /* Go through the explicit initializers, filling in TREE_PURPOSE in
1091 the SORTED_INITS. */
1092 for (init = mem_inits; init; init = TREE_CHAIN (init))
1093 {
1094 tree subobject;
1095 tree subobject_init;
1096
1097 subobject = TREE_PURPOSE (init);
1098
1099 /* If the explicit initializers are in sorted order, then
1100 SUBOBJECT will be NEXT_SUBOBJECT, or something following
1101 it. */
1102 for (subobject_init = next_subobject;
1103 subobject_init;
1104 subobject_init = TREE_CHAIN (subobject_init))
1105 if (TREE_PURPOSE (subobject_init) == subobject)
1106 break;
1107
1108 /* Issue a warning if the explicit initializer order does not
1109 match that which will actually occur.
1110 ??? Are all these on the correct lines? */
1111 if (warn_reorder && !subobject_init)
1112 {
1113 if (TREE_CODE (TREE_PURPOSE (next_subobject)) == FIELD_DECL)
1114 warning_at (DECL_SOURCE_LOCATION (TREE_PURPOSE (next_subobject)),
1115 OPT_Wreorder, "%qD will be initialized after",
1116 TREE_PURPOSE (next_subobject));
1117 else
1118 warning (OPT_Wreorder, "base %qT will be initialized after",
1119 TREE_PURPOSE (next_subobject));
1120 if (TREE_CODE (subobject) == FIELD_DECL)
1121 warning_at (DECL_SOURCE_LOCATION (subobject),
1122 OPT_Wreorder, " %q#D", subobject);
1123 else
1124 warning (OPT_Wreorder, " base %qT", subobject);
1125 warning_at (DECL_SOURCE_LOCATION (current_function_decl),
1126 OPT_Wreorder, " when initialized here");
1127 }
1128
1129 /* Look again, from the beginning of the list. */
1130 if (!subobject_init)
1131 {
1132 subobject_init = sorted_inits;
1133 while (TREE_PURPOSE (subobject_init) != subobject)
1134 subobject_init = TREE_CHAIN (subobject_init);
1135 }
1136
1137 /* It is invalid to initialize the same subobject more than
1138 once. */
1139 if (TREE_VALUE (subobject_init))
1140 {
1141 if (TREE_CODE (subobject) == FIELD_DECL)
1142 error_at (DECL_SOURCE_LOCATION (current_function_decl),
1143 "multiple initializations given for %qD",
1144 subobject);
1145 else
1146 error_at (DECL_SOURCE_LOCATION (current_function_decl),
1147 "multiple initializations given for base %qT",
1148 subobject);
1149 }
1150
1151 /* Record the initialization. */
1152 TREE_VALUE (subobject_init) = TREE_VALUE (init);
1153 next_subobject = subobject_init;
1154 }
1155
1156 /* [class.base.init]
1157
1158 If a ctor-initializer specifies more than one mem-initializer for
1159 multiple members of the same union (including members of
1160 anonymous unions), the ctor-initializer is ill-formed.
1161
1162 Here we also splice out uninitialized union members. */
1163 if (uses_unions_or_anon_p)
1164 {
1165 tree *last_p = NULL;
1166 tree *p;
1167 for (p = &sorted_inits; *p; )
1168 {
1169 tree field;
1170 tree ctx;
1171
1172 init = *p;
1173
1174 field = TREE_PURPOSE (init);
1175
1176 /* Skip base classes. */
1177 if (TREE_CODE (field) != FIELD_DECL)
1178 goto next;
1179
1180 /* If this is an anonymous aggregate with no explicit initializer,
1181 splice it out. */
1182 if (!TREE_VALUE (init) && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1183 goto splice;
1184
1185 /* See if this field is a member of a union, or a member of a
1186 structure contained in a union, etc. */
1187 ctx = innermost_aggr_scope (field);
1188
1189 /* If this field is not a member of a union, skip it. */
1190 if (TREE_CODE (ctx) != UNION_TYPE
1191 && !ANON_AGGR_TYPE_P (ctx))
1192 goto next;
1193
1194 /* If this union member has no explicit initializer and no NSDMI,
1195 splice it out. */
1196 if (TREE_VALUE (init) || DECL_INITIAL (field))
1197 /* OK. */;
1198 else
1199 goto splice;
1200
1201 /* It's only an error if we have two initializers for the same
1202 union type. */
1203 if (!last_p)
1204 {
1205 last_p = p;
1206 goto next;
1207 }
1208
1209 /* See if LAST_FIELD and the field initialized by INIT are
1210 members of the same union (or the union itself). If so, there's
1211 a problem, unless they're actually members of the same structure
1212 which is itself a member of a union. For example, given:
1213
1214 union { struct { int i; int j; }; };
1215
1216 initializing both `i' and `j' makes sense. */
1217 ctx = common_enclosing_class
1218 (innermost_aggr_scope (field),
1219 innermost_aggr_scope (TREE_PURPOSE (*last_p)));
1220
1221 if (ctx && (TREE_CODE (ctx) == UNION_TYPE
1222 || ctx == TREE_TYPE (TREE_PURPOSE (*last_p))))
1223 {
1224 /* A mem-initializer hides an NSDMI. */
1225 if (TREE_VALUE (init) && !TREE_VALUE (*last_p))
1226 *last_p = TREE_CHAIN (*last_p);
1227 else if (TREE_VALUE (*last_p) && !TREE_VALUE (init))
1228 goto splice;
1229 else
1230 {
1231 error_at (DECL_SOURCE_LOCATION (current_function_decl),
1232 "initializations for multiple members of %qT",
1233 ctx);
1234 goto splice;
1235 }
1236 }
1237
1238 last_p = p;
1239
1240 next:
1241 p = &TREE_CHAIN (*p);
1242 continue;
1243 splice:
1244 *p = TREE_CHAIN (*p);
1245 continue;
1246 }
1247 }
1248
1249 return sorted_inits;
1250 }
1251
1252 /* Callback for cp_walk_tree to mark all PARM_DECLs in a tree as read. */
1253
1254 static tree
mark_exp_read_r(tree * tp,int *,void *)1255 mark_exp_read_r (tree *tp, int *, void *)
1256 {
1257 tree t = *tp;
1258 if (TREE_CODE (t) == PARM_DECL)
1259 mark_exp_read (t);
1260 return NULL_TREE;
1261 }
1262
1263 /* Initialize all bases and members of CURRENT_CLASS_TYPE. MEM_INITS
1264 is a TREE_LIST giving the explicit mem-initializer-list for the
1265 constructor. The TREE_PURPOSE of each entry is a subobject (a
1266 FIELD_DECL or a BINFO) of the CURRENT_CLASS_TYPE. The TREE_VALUE
1267 is a TREE_LIST giving the arguments to the constructor or
1268 void_type_node for an empty list of arguments. */
1269
1270 void
emit_mem_initializers(tree mem_inits)1271 emit_mem_initializers (tree mem_inits)
1272 {
1273 int flags = LOOKUP_NORMAL;
1274
1275 /* We will already have issued an error message about the fact that
1276 the type is incomplete. */
1277 if (!COMPLETE_TYPE_P (current_class_type))
1278 return;
1279
1280 if (mem_inits
1281 && TYPE_P (TREE_PURPOSE (mem_inits))
1282 && same_type_p (TREE_PURPOSE (mem_inits), current_class_type))
1283 {
1284 /* Delegating constructor. */
1285 gcc_assert (TREE_CHAIN (mem_inits) == NULL_TREE);
1286 perform_target_ctor (TREE_VALUE (mem_inits));
1287 return;
1288 }
1289
1290 if (DECL_DEFAULTED_FN (current_function_decl)
1291 && ! DECL_INHERITED_CTOR (current_function_decl))
1292 flags |= LOOKUP_DEFAULTED;
1293
1294 /* Sort the mem-initializers into the order in which the
1295 initializations should be performed. */
1296 mem_inits = sort_mem_initializers (current_class_type, mem_inits);
1297
1298 in_base_initializer = 1;
1299
1300 /* Initialize base classes. */
1301 for (; (mem_inits
1302 && TREE_CODE (TREE_PURPOSE (mem_inits)) != FIELD_DECL);
1303 mem_inits = TREE_CHAIN (mem_inits))
1304 {
1305 tree subobject = TREE_PURPOSE (mem_inits);
1306 tree arguments = TREE_VALUE (mem_inits);
1307
1308 /* We already have issued an error message. */
1309 if (arguments == error_mark_node)
1310 continue;
1311
1312 /* Suppress access control when calling the inherited ctor. */
1313 bool inherited_base = (DECL_INHERITED_CTOR (current_function_decl)
1314 && flag_new_inheriting_ctors
1315 && arguments);
1316 if (inherited_base)
1317 push_deferring_access_checks (dk_deferred);
1318
1319 if (arguments == NULL_TREE)
1320 {
1321 /* If these initializations are taking place in a copy constructor,
1322 the base class should probably be explicitly initialized if there
1323 is a user-defined constructor in the base class (other than the
1324 default constructor, which will be called anyway). */
1325 if (extra_warnings
1326 && DECL_COPY_CONSTRUCTOR_P (current_function_decl)
1327 && type_has_user_nondefault_constructor (BINFO_TYPE (subobject)))
1328 warning_at (DECL_SOURCE_LOCATION (current_function_decl),
1329 OPT_Wextra, "base class %q#T should be explicitly "
1330 "initialized in the copy constructor",
1331 BINFO_TYPE (subobject));
1332 }
1333
1334 /* Initialize the base. */
1335 if (!BINFO_VIRTUAL_P (subobject))
1336 {
1337 tree base_addr;
1338
1339 base_addr = build_base_path (PLUS_EXPR, current_class_ptr,
1340 subobject, 1, tf_warning_or_error);
1341 expand_aggr_init_1 (subobject, NULL_TREE,
1342 cp_build_fold_indirect_ref (base_addr),
1343 arguments,
1344 flags,
1345 tf_warning_or_error);
1346 expand_cleanup_for_base (subobject, NULL_TREE);
1347 }
1348 else if (!ABSTRACT_CLASS_TYPE_P (current_class_type))
1349 /* C++14 DR1658 Means we do not have to construct vbases of
1350 abstract classes. */
1351 construct_virtual_base (subobject, arguments);
1352 else
1353 /* When not constructing vbases of abstract classes, at least mark
1354 the arguments expressions as read to avoid
1355 -Wunused-but-set-parameter false positives. */
1356 cp_walk_tree (&arguments, mark_exp_read_r, NULL, NULL);
1357
1358 if (inherited_base)
1359 pop_deferring_access_checks ();
1360 }
1361 in_base_initializer = 0;
1362
1363 /* Initialize the vptrs. */
1364 initialize_vtbl_ptrs (current_class_ptr);
1365
1366 /* Initialize the data members. */
1367 while (mem_inits)
1368 {
1369 perform_member_init (TREE_PURPOSE (mem_inits),
1370 TREE_VALUE (mem_inits));
1371 mem_inits = TREE_CHAIN (mem_inits);
1372 }
1373 }
1374
1375 /* Returns the address of the vtable (i.e., the value that should be
1376 assigned to the vptr) for BINFO. */
1377
1378 tree
build_vtbl_address(tree binfo)1379 build_vtbl_address (tree binfo)
1380 {
1381 tree binfo_for = binfo;
1382 tree vtbl;
1383
1384 if (BINFO_VPTR_INDEX (binfo) && BINFO_VIRTUAL_P (binfo))
1385 /* If this is a virtual primary base, then the vtable we want to store
1386 is that for the base this is being used as the primary base of. We
1387 can't simply skip the initialization, because we may be expanding the
1388 inits of a subobject constructor where the virtual base layout
1389 can be different. */
1390 while (BINFO_PRIMARY_P (binfo_for))
1391 binfo_for = BINFO_INHERITANCE_CHAIN (binfo_for);
1392
1393 /* Figure out what vtable BINFO's vtable is based on, and mark it as
1394 used. */
1395 vtbl = get_vtbl_decl_for_binfo (binfo_for);
1396 TREE_USED (vtbl) = true;
1397
1398 /* Now compute the address to use when initializing the vptr. */
1399 vtbl = unshare_expr (BINFO_VTABLE (binfo_for));
1400 if (VAR_P (vtbl))
1401 vtbl = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (vtbl)), vtbl);
1402
1403 return vtbl;
1404 }
1405
1406 /* This code sets up the virtual function tables appropriate for
1407 the pointer DECL. It is a one-ply initialization.
1408
1409 BINFO is the exact type that DECL is supposed to be. In
1410 multiple inheritance, this might mean "C's A" if C : A, B. */
1411
1412 static void
expand_virtual_init(tree binfo,tree decl)1413 expand_virtual_init (tree binfo, tree decl)
1414 {
1415 tree vtbl, vtbl_ptr;
1416 tree vtt_index;
1417
1418 /* Compute the initializer for vptr. */
1419 vtbl = build_vtbl_address (binfo);
1420
1421 /* We may get this vptr from a VTT, if this is a subobject
1422 constructor or subobject destructor. */
1423 vtt_index = BINFO_VPTR_INDEX (binfo);
1424 if (vtt_index)
1425 {
1426 tree vtbl2;
1427 tree vtt_parm;
1428
1429 /* Compute the value to use, when there's a VTT. */
1430 vtt_parm = current_vtt_parm;
1431 vtbl2 = fold_build_pointer_plus (vtt_parm, vtt_index);
1432 vtbl2 = cp_build_fold_indirect_ref (vtbl2);
1433 vtbl2 = convert (TREE_TYPE (vtbl), vtbl2);
1434
1435 /* The actual initializer is the VTT value only in the subobject
1436 constructor. In maybe_clone_body we'll substitute NULL for
1437 the vtt_parm in the case of the non-subobject constructor. */
1438 vtbl = build_if_in_charge (vtbl, vtbl2);
1439 }
1440
1441 /* Compute the location of the vtpr. */
1442 vtbl_ptr = build_vfield_ref (cp_build_fold_indirect_ref (decl),
1443 TREE_TYPE (binfo));
1444 gcc_assert (vtbl_ptr != error_mark_node);
1445
1446 /* Assign the vtable to the vptr. */
1447 vtbl = convert_force (TREE_TYPE (vtbl_ptr), vtbl, 0, tf_warning_or_error);
1448 finish_expr_stmt (cp_build_modify_expr (input_location, vtbl_ptr, NOP_EXPR,
1449 vtbl, tf_warning_or_error));
1450 }
1451
1452 /* If an exception is thrown in a constructor, those base classes already
1453 constructed must be destroyed. This function creates the cleanup
1454 for BINFO, which has just been constructed. If FLAG is non-NULL,
1455 it is a DECL which is nonzero when this base needs to be
1456 destroyed. */
1457
1458 static void
expand_cleanup_for_base(tree binfo,tree flag)1459 expand_cleanup_for_base (tree binfo, tree flag)
1460 {
1461 tree expr;
1462
1463 if (!type_build_dtor_call (BINFO_TYPE (binfo)))
1464 return;
1465
1466 /* Call the destructor. */
1467 expr = build_special_member_call (current_class_ref,
1468 base_dtor_identifier,
1469 NULL,
1470 binfo,
1471 LOOKUP_NORMAL | LOOKUP_NONVIRTUAL,
1472 tf_warning_or_error);
1473
1474 if (TYPE_HAS_TRIVIAL_DESTRUCTOR (BINFO_TYPE (binfo)))
1475 return;
1476
1477 if (flag)
1478 expr = fold_build3_loc (input_location,
1479 COND_EXPR, void_type_node,
1480 c_common_truthvalue_conversion (input_location, flag),
1481 expr, integer_zero_node);
1482
1483 finish_eh_cleanup (expr);
1484 }
1485
1486 /* Construct the virtual base-class VBASE passing the ARGUMENTS to its
1487 constructor. */
1488
1489 static void
construct_virtual_base(tree vbase,tree arguments)1490 construct_virtual_base (tree vbase, tree arguments)
1491 {
1492 tree inner_if_stmt;
1493 tree exp;
1494 tree flag;
1495
1496 /* If there are virtual base classes with destructors, we need to
1497 emit cleanups to destroy them if an exception is thrown during
1498 the construction process. These exception regions (i.e., the
1499 period during which the cleanups must occur) begin from the time
1500 the construction is complete to the end of the function. If we
1501 create a conditional block in which to initialize the
1502 base-classes, then the cleanup region for the virtual base begins
1503 inside a block, and ends outside of that block. This situation
1504 confuses the sjlj exception-handling code. Therefore, we do not
1505 create a single conditional block, but one for each
1506 initialization. (That way the cleanup regions always begin
1507 in the outer block.) We trust the back end to figure out
1508 that the FLAG will not change across initializations, and
1509 avoid doing multiple tests. */
1510 flag = DECL_CHAIN (DECL_ARGUMENTS (current_function_decl));
1511 inner_if_stmt = begin_if_stmt ();
1512 finish_if_stmt_cond (flag, inner_if_stmt);
1513
1514 /* Compute the location of the virtual base. If we're
1515 constructing virtual bases, then we must be the most derived
1516 class. Therefore, we don't have to look up the virtual base;
1517 we already know where it is. */
1518 exp = convert_to_base_statically (current_class_ref, vbase);
1519
1520 expand_aggr_init_1 (vbase, current_class_ref, exp, arguments,
1521 0, tf_warning_or_error);
1522 finish_then_clause (inner_if_stmt);
1523 finish_if_stmt (inner_if_stmt);
1524
1525 expand_cleanup_for_base (vbase, flag);
1526 }
1527
1528 /* Find the context in which this FIELD can be initialized. */
1529
1530 static tree
initializing_context(tree field)1531 initializing_context (tree field)
1532 {
1533 tree t = DECL_CONTEXT (field);
1534
1535 /* Anonymous union members can be initialized in the first enclosing
1536 non-anonymous union context. */
1537 while (t && ANON_AGGR_TYPE_P (t))
1538 t = TYPE_CONTEXT (t);
1539 return t;
1540 }
1541
1542 /* Function to give error message if member initialization specification
1543 is erroneous. FIELD is the member we decided to initialize.
1544 TYPE is the type for which the initialization is being performed.
1545 FIELD must be a member of TYPE.
1546
1547 MEMBER_NAME is the name of the member. */
1548
1549 static int
member_init_ok_or_else(tree field,tree type,tree member_name)1550 member_init_ok_or_else (tree field, tree type, tree member_name)
1551 {
1552 if (field == error_mark_node)
1553 return 0;
1554 if (!field)
1555 {
1556 error ("class %qT does not have any field named %qD", type,
1557 member_name);
1558 return 0;
1559 }
1560 if (VAR_P (field))
1561 {
1562 error ("%q#D is a static data member; it can only be "
1563 "initialized at its definition",
1564 field);
1565 return 0;
1566 }
1567 if (TREE_CODE (field) != FIELD_DECL)
1568 {
1569 error ("%q#D is not a non-static data member of %qT",
1570 field, type);
1571 return 0;
1572 }
1573 if (initializing_context (field) != type)
1574 {
1575 error ("class %qT does not have any field named %qD", type,
1576 member_name);
1577 return 0;
1578 }
1579
1580 return 1;
1581 }
1582
1583 /* NAME is a FIELD_DECL, an IDENTIFIER_NODE which names a field, or it
1584 is a _TYPE node or TYPE_DECL which names a base for that type.
1585 Check the validity of NAME, and return either the base _TYPE, base
1586 binfo, or the FIELD_DECL of the member. If NAME is invalid, return
1587 NULL_TREE and issue a diagnostic.
1588
1589 An old style unnamed direct single base construction is permitted,
1590 where NAME is NULL. */
1591
1592 tree
expand_member_init(tree name)1593 expand_member_init (tree name)
1594 {
1595 tree basetype;
1596 tree field;
1597
1598 if (!current_class_ref)
1599 return NULL_TREE;
1600
1601 if (!name)
1602 {
1603 /* This is an obsolete unnamed base class initializer. The
1604 parser will already have warned about its use. */
1605 switch (BINFO_N_BASE_BINFOS (TYPE_BINFO (current_class_type)))
1606 {
1607 case 0:
1608 error ("unnamed initializer for %qT, which has no base classes",
1609 current_class_type);
1610 return NULL_TREE;
1611 case 1:
1612 basetype = BINFO_TYPE
1613 (BINFO_BASE_BINFO (TYPE_BINFO (current_class_type), 0));
1614 break;
1615 default:
1616 error ("unnamed initializer for %qT, which uses multiple inheritance",
1617 current_class_type);
1618 return NULL_TREE;
1619 }
1620 }
1621 else if (TYPE_P (name))
1622 {
1623 basetype = TYPE_MAIN_VARIANT (name);
1624 name = TYPE_NAME (name);
1625 }
1626 else if (TREE_CODE (name) == TYPE_DECL)
1627 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (name));
1628 else
1629 basetype = NULL_TREE;
1630
1631 if (basetype)
1632 {
1633 tree class_binfo;
1634 tree direct_binfo;
1635 tree virtual_binfo;
1636 int i;
1637
1638 if (current_template_parms
1639 || same_type_p (basetype, current_class_type))
1640 return basetype;
1641
1642 class_binfo = TYPE_BINFO (current_class_type);
1643 direct_binfo = NULL_TREE;
1644 virtual_binfo = NULL_TREE;
1645
1646 /* Look for a direct base. */
1647 for (i = 0; BINFO_BASE_ITERATE (class_binfo, i, direct_binfo); ++i)
1648 if (SAME_BINFO_TYPE_P (BINFO_TYPE (direct_binfo), basetype))
1649 break;
1650
1651 /* Look for a virtual base -- unless the direct base is itself
1652 virtual. */
1653 if (!direct_binfo || !BINFO_VIRTUAL_P (direct_binfo))
1654 virtual_binfo = binfo_for_vbase (basetype, current_class_type);
1655
1656 /* [class.base.init]
1657
1658 If a mem-initializer-id is ambiguous because it designates
1659 both a direct non-virtual base class and an inherited virtual
1660 base class, the mem-initializer is ill-formed. */
1661 if (direct_binfo && virtual_binfo)
1662 {
1663 error ("%qD is both a direct base and an indirect virtual base",
1664 basetype);
1665 return NULL_TREE;
1666 }
1667
1668 if (!direct_binfo && !virtual_binfo)
1669 {
1670 if (CLASSTYPE_VBASECLASSES (current_class_type))
1671 error ("type %qT is not a direct or virtual base of %qT",
1672 basetype, current_class_type);
1673 else
1674 error ("type %qT is not a direct base of %qT",
1675 basetype, current_class_type);
1676 return NULL_TREE;
1677 }
1678
1679 return direct_binfo ? direct_binfo : virtual_binfo;
1680 }
1681 else
1682 {
1683 if (identifier_p (name))
1684 field = lookup_field (current_class_type, name, 1, false);
1685 else
1686 field = name;
1687
1688 if (member_init_ok_or_else (field, current_class_type, name))
1689 return field;
1690 }
1691
1692 return NULL_TREE;
1693 }
1694
1695 /* This is like `expand_member_init', only it stores one aggregate
1696 value into another.
1697
1698 INIT comes in two flavors: it is either a value which
1699 is to be stored in EXP, or it is a parameter list
1700 to go to a constructor, which will operate on EXP.
1701 If INIT is not a parameter list for a constructor, then set
1702 LOOKUP_ONLYCONVERTING.
1703 If FLAGS is LOOKUP_ONLYCONVERTING then it is the = init form of
1704 the initializer, if FLAGS is 0, then it is the (init) form.
1705 If `init' is a CONSTRUCTOR, then we emit a warning message,
1706 explaining that such initializations are invalid.
1707
1708 If INIT resolves to a CALL_EXPR which happens to return
1709 something of the type we are looking for, then we know
1710 that we can safely use that call to perform the
1711 initialization.
1712
1713 The virtual function table pointer cannot be set up here, because
1714 we do not really know its type.
1715
1716 This never calls operator=().
1717
1718 When initializing, nothing is CONST.
1719
1720 A default copy constructor may have to be used to perform the
1721 initialization.
1722
1723 A constructor or a conversion operator may have to be used to
1724 perform the initialization, but not both, as it would be ambiguous. */
1725
1726 tree
build_aggr_init(tree exp,tree init,int flags,tsubst_flags_t complain)1727 build_aggr_init (tree exp, tree init, int flags, tsubst_flags_t complain)
1728 {
1729 tree stmt_expr;
1730 tree compound_stmt;
1731 int destroy_temps;
1732 tree type = TREE_TYPE (exp);
1733 int was_const = TREE_READONLY (exp);
1734 int was_volatile = TREE_THIS_VOLATILE (exp);
1735 int is_global;
1736
1737 if (init == error_mark_node)
1738 return error_mark_node;
1739
1740 location_t init_loc = (init
1741 ? cp_expr_loc_or_input_loc (init)
1742 : location_of (exp));
1743
1744 TREE_READONLY (exp) = 0;
1745 TREE_THIS_VOLATILE (exp) = 0;
1746
1747 if (TREE_CODE (type) == ARRAY_TYPE)
1748 {
1749 tree itype = init ? TREE_TYPE (init) : NULL_TREE;
1750 int from_array = 0;
1751
1752 if (VAR_P (exp) && DECL_DECOMPOSITION_P (exp))
1753 {
1754 from_array = 1;
1755 init = mark_rvalue_use (init);
1756 if (init
1757 && DECL_P (tree_strip_any_location_wrapper (init))
1758 && !(flags & LOOKUP_ONLYCONVERTING))
1759 {
1760 /* Wrap the initializer in a CONSTRUCTOR so that build_vec_init
1761 recognizes it as direct-initialization. */
1762 init = build_constructor_single (init_list_type_node,
1763 NULL_TREE, init);
1764 CONSTRUCTOR_IS_DIRECT_INIT (init) = true;
1765 }
1766 }
1767 else
1768 {
1769 /* Must arrange to initialize each element of EXP
1770 from elements of INIT. */
1771 if (cv_qualified_p (type))
1772 TREE_TYPE (exp) = cv_unqualified (type);
1773 if (itype && cv_qualified_p (itype))
1774 TREE_TYPE (init) = cv_unqualified (itype);
1775 from_array = (itype && same_type_p (TREE_TYPE (init),
1776 TREE_TYPE (exp)));
1777
1778 if (init && !BRACE_ENCLOSED_INITIALIZER_P (init)
1779 && (!from_array
1780 || (TREE_CODE (init) != CONSTRUCTOR
1781 /* Can happen, eg, handling the compound-literals
1782 extension (ext/complit12.C). */
1783 && TREE_CODE (init) != TARGET_EXPR)))
1784 {
1785 if (complain & tf_error)
1786 error_at (init_loc, "array must be initialized "
1787 "with a brace-enclosed initializer");
1788 return error_mark_node;
1789 }
1790 }
1791
1792 stmt_expr = build_vec_init (exp, NULL_TREE, init,
1793 /*explicit_value_init_p=*/false,
1794 from_array,
1795 complain);
1796 TREE_READONLY (exp) = was_const;
1797 TREE_THIS_VOLATILE (exp) = was_volatile;
1798 TREE_TYPE (exp) = type;
1799 /* Restore the type of init unless it was used directly. */
1800 if (init && TREE_CODE (stmt_expr) != INIT_EXPR)
1801 TREE_TYPE (init) = itype;
1802 return stmt_expr;
1803 }
1804
1805 if (init && init != void_type_node
1806 && TREE_CODE (init) != TREE_LIST
1807 && !(TREE_CODE (init) == TARGET_EXPR
1808 && TARGET_EXPR_DIRECT_INIT_P (init))
1809 && !DIRECT_LIST_INIT_P (init))
1810 flags |= LOOKUP_ONLYCONVERTING;
1811
1812 is_global = begin_init_stmts (&stmt_expr, &compound_stmt);
1813 destroy_temps = stmts_are_full_exprs_p ();
1814 current_stmt_tree ()->stmts_are_full_exprs_p = 0;
1815 expand_aggr_init_1 (TYPE_BINFO (type), exp, exp,
1816 init, LOOKUP_NORMAL|flags, complain);
1817 stmt_expr = finish_init_stmts (is_global, stmt_expr, compound_stmt);
1818 current_stmt_tree ()->stmts_are_full_exprs_p = destroy_temps;
1819 TREE_READONLY (exp) = was_const;
1820 TREE_THIS_VOLATILE (exp) = was_volatile;
1821
1822 if ((VAR_P (exp) || TREE_CODE (exp) == PARM_DECL)
1823 && TREE_SIDE_EFFECTS (stmt_expr)
1824 && !lookup_attribute ("warn_unused", TYPE_ATTRIBUTES (type)))
1825 /* Just know that we've seen something for this node. */
1826 TREE_USED (exp) = 1;
1827
1828 return stmt_expr;
1829 }
1830
1831 static void
expand_default_init(tree binfo,tree true_exp,tree exp,tree init,int flags,tsubst_flags_t complain)1832 expand_default_init (tree binfo, tree true_exp, tree exp, tree init, int flags,
1833 tsubst_flags_t complain)
1834 {
1835 tree type = TREE_TYPE (exp);
1836
1837 /* It fails because there may not be a constructor which takes
1838 its own type as the first (or only parameter), but which does
1839 take other types via a conversion. So, if the thing initializing
1840 the expression is a unit element of type X, first try X(X&),
1841 followed by initialization by X. If neither of these work
1842 out, then look hard. */
1843 tree rval;
1844 vec<tree, va_gc> *parms;
1845
1846 /* If we have direct-initialization from an initializer list, pull
1847 it out of the TREE_LIST so the code below can see it. */
1848 if (init && TREE_CODE (init) == TREE_LIST
1849 && DIRECT_LIST_INIT_P (TREE_VALUE (init)))
1850 {
1851 gcc_checking_assert ((flags & LOOKUP_ONLYCONVERTING) == 0
1852 && TREE_CHAIN (init) == NULL_TREE);
1853 init = TREE_VALUE (init);
1854 /* Only call reshape_init if it has not been called earlier
1855 by the callers. */
1856 if (BRACE_ENCLOSED_INITIALIZER_P (init) && CP_AGGREGATE_TYPE_P (type))
1857 init = reshape_init (type, init, complain);
1858 }
1859
1860 if (init && BRACE_ENCLOSED_INITIALIZER_P (init)
1861 && CP_AGGREGATE_TYPE_P (type))
1862 /* A brace-enclosed initializer for an aggregate. In C++0x this can
1863 happen for direct-initialization, too. */
1864 init = digest_init (type, init, complain);
1865
1866 /* A CONSTRUCTOR of the target's type is a previously digested
1867 initializer, whether that happened just above or in
1868 cp_parser_late_parsing_nsdmi.
1869
1870 A TARGET_EXPR with TARGET_EXPR_DIRECT_INIT_P or TARGET_EXPR_LIST_INIT_P
1871 set represents the whole initialization, so we shouldn't build up
1872 another ctor call. */
1873 if (init
1874 && (TREE_CODE (init) == CONSTRUCTOR
1875 || (TREE_CODE (init) == TARGET_EXPR
1876 && (TARGET_EXPR_DIRECT_INIT_P (init)
1877 || TARGET_EXPR_LIST_INIT_P (init))))
1878 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (init), type))
1879 {
1880 /* Early initialization via a TARGET_EXPR only works for
1881 complete objects. */
1882 gcc_assert (TREE_CODE (init) == CONSTRUCTOR || true_exp == exp);
1883
1884 init = build2 (INIT_EXPR, TREE_TYPE (exp), exp, init);
1885 TREE_SIDE_EFFECTS (init) = 1;
1886 finish_expr_stmt (init);
1887 return;
1888 }
1889
1890 if (init && TREE_CODE (init) != TREE_LIST
1891 && (flags & LOOKUP_ONLYCONVERTING)
1892 && !unsafe_return_slot_p (exp))
1893 {
1894 /* Base subobjects should only get direct-initialization. */
1895 gcc_assert (true_exp == exp);
1896
1897 if (flags & DIRECT_BIND)
1898 /* Do nothing. We hit this in two cases: Reference initialization,
1899 where we aren't initializing a real variable, so we don't want
1900 to run a new constructor; and catching an exception, where we
1901 have already built up the constructor call so we could wrap it
1902 in an exception region. */;
1903 else
1904 init = ocp_convert (type, init, CONV_IMPLICIT|CONV_FORCE_TEMP,
1905 flags, complain);
1906
1907 if (TREE_CODE (init) == MUST_NOT_THROW_EXPR)
1908 /* We need to protect the initialization of a catch parm with a
1909 call to terminate(), which shows up as a MUST_NOT_THROW_EXPR
1910 around the TARGET_EXPR for the copy constructor. See
1911 initialize_handler_parm. */
1912 {
1913 TREE_OPERAND (init, 0) = build2 (INIT_EXPR, TREE_TYPE (exp), exp,
1914 TREE_OPERAND (init, 0));
1915 TREE_TYPE (init) = void_type_node;
1916 }
1917 else
1918 init = build2 (INIT_EXPR, TREE_TYPE (exp), exp, init);
1919 TREE_SIDE_EFFECTS (init) = 1;
1920 finish_expr_stmt (init);
1921 return;
1922 }
1923
1924 if (init == NULL_TREE)
1925 parms = NULL;
1926 else if (TREE_CODE (init) == TREE_LIST && !TREE_TYPE (init))
1927 {
1928 parms = make_tree_vector ();
1929 for (; init != NULL_TREE; init = TREE_CHAIN (init))
1930 vec_safe_push (parms, TREE_VALUE (init));
1931 }
1932 else
1933 parms = make_tree_vector_single (init);
1934
1935 if (exp == current_class_ref && current_function_decl
1936 && DECL_HAS_IN_CHARGE_PARM_P (current_function_decl))
1937 {
1938 /* Delegating constructor. */
1939 tree complete;
1940 tree base;
1941 tree elt; unsigned i;
1942
1943 /* Unshare the arguments for the second call. */
1944 releasing_vec parms2;
1945 FOR_EACH_VEC_SAFE_ELT (parms, i, elt)
1946 {
1947 elt = break_out_target_exprs (elt);
1948 vec_safe_push (parms2, elt);
1949 }
1950 complete = build_special_member_call (exp, complete_ctor_identifier,
1951 &parms2, binfo, flags,
1952 complain);
1953 complete = fold_build_cleanup_point_expr (void_type_node, complete);
1954
1955 base = build_special_member_call (exp, base_ctor_identifier,
1956 &parms, binfo, flags,
1957 complain);
1958 base = fold_build_cleanup_point_expr (void_type_node, base);
1959 rval = build_if_in_charge (complete, base);
1960 }
1961 else
1962 {
1963 tree ctor_name = (true_exp == exp
1964 ? complete_ctor_identifier : base_ctor_identifier);
1965
1966 rval = build_special_member_call (exp, ctor_name, &parms, binfo, flags,
1967 complain);
1968 }
1969
1970 if (parms != NULL)
1971 release_tree_vector (parms);
1972
1973 if (exp == true_exp && TREE_CODE (rval) == CALL_EXPR)
1974 {
1975 tree fn = get_callee_fndecl (rval);
1976 if (fn && DECL_DECLARED_CONSTEXPR_P (fn))
1977 {
1978 tree e = maybe_constant_init (rval, exp);
1979 if (TREE_CONSTANT (e))
1980 rval = build2 (INIT_EXPR, type, exp, e);
1981 }
1982 }
1983
1984 /* FIXME put back convert_to_void? */
1985 if (TREE_SIDE_EFFECTS (rval))
1986 finish_expr_stmt (rval);
1987 }
1988
1989 /* This function is responsible for initializing EXP with INIT
1990 (if any).
1991
1992 BINFO is the binfo of the type for who we are performing the
1993 initialization. For example, if W is a virtual base class of A and B,
1994 and C : A, B.
1995 If we are initializing B, then W must contain B's W vtable, whereas
1996 were we initializing C, W must contain C's W vtable.
1997
1998 TRUE_EXP is nonzero if it is the true expression being initialized.
1999 In this case, it may be EXP, or may just contain EXP. The reason we
2000 need this is because if EXP is a base element of TRUE_EXP, we
2001 don't necessarily know by looking at EXP where its virtual
2002 baseclass fields should really be pointing. But we do know
2003 from TRUE_EXP. In constructors, we don't know anything about
2004 the value being initialized.
2005
2006 FLAGS is just passed to `build_new_method_call'. See that function
2007 for its description. */
2008
2009 static void
expand_aggr_init_1(tree binfo,tree true_exp,tree exp,tree init,int flags,tsubst_flags_t complain)2010 expand_aggr_init_1 (tree binfo, tree true_exp, tree exp, tree init, int flags,
2011 tsubst_flags_t complain)
2012 {
2013 tree type = TREE_TYPE (exp);
2014
2015 gcc_assert (init != error_mark_node && type != error_mark_node);
2016 gcc_assert (building_stmt_list_p ());
2017
2018 /* Use a function returning the desired type to initialize EXP for us.
2019 If the function is a constructor, and its first argument is
2020 NULL_TREE, know that it was meant for us--just slide exp on
2021 in and expand the constructor. Constructors now come
2022 as TARGET_EXPRs. */
2023
2024 if (init && VAR_P (exp)
2025 && COMPOUND_LITERAL_P (init))
2026 {
2027 vec<tree, va_gc> *cleanups = NULL;
2028 /* If store_init_value returns NULL_TREE, the INIT has been
2029 recorded as the DECL_INITIAL for EXP. That means there's
2030 nothing more we have to do. */
2031 init = store_init_value (exp, init, &cleanups, flags);
2032 if (init)
2033 finish_expr_stmt (init);
2034 gcc_assert (!cleanups);
2035 return;
2036 }
2037
2038 /* List-initialization from {} becomes value-initialization for non-aggregate
2039 classes with default constructors. Handle this here when we're
2040 initializing a base, so protected access works. */
2041 if (exp != true_exp && init && TREE_CODE (init) == TREE_LIST)
2042 {
2043 tree elt = TREE_VALUE (init);
2044 if (DIRECT_LIST_INIT_P (elt)
2045 && CONSTRUCTOR_ELTS (elt) == 0
2046 && CLASSTYPE_NON_AGGREGATE (type)
2047 && TYPE_HAS_DEFAULT_CONSTRUCTOR (type))
2048 init = void_type_node;
2049 }
2050
2051 /* If an explicit -- but empty -- initializer list was present,
2052 that's value-initialization. */
2053 if (init == void_type_node)
2054 {
2055 /* If the type has data but no user-provided ctor, we need to zero
2056 out the object. */
2057 if (!type_has_user_provided_constructor (type)
2058 && !is_really_empty_class (type, /*ignore_vptr*/true))
2059 {
2060 tree field_size = NULL_TREE;
2061 if (exp != true_exp && CLASSTYPE_AS_BASE (type) != type)
2062 /* Don't clobber already initialized virtual bases. */
2063 field_size = TYPE_SIZE (CLASSTYPE_AS_BASE (type));
2064 init = build_zero_init_1 (type, NULL_TREE, /*static_storage_p=*/false,
2065 field_size);
2066 init = build2 (INIT_EXPR, type, exp, init);
2067 finish_expr_stmt (init);
2068 }
2069
2070 /* If we don't need to mess with the constructor at all,
2071 then we're done. */
2072 if (! type_build_ctor_call (type))
2073 return;
2074
2075 /* Otherwise fall through and call the constructor. */
2076 init = NULL_TREE;
2077 }
2078
2079 /* We know that expand_default_init can handle everything we want
2080 at this point. */
2081 expand_default_init (binfo, true_exp, exp, init, flags, complain);
2082 }
2083
2084 /* Report an error if TYPE is not a user-defined, class type. If
2085 OR_ELSE is nonzero, give an error message. */
2086
2087 int
is_class_type(tree type,int or_else)2088 is_class_type (tree type, int or_else)
2089 {
2090 if (type == error_mark_node)
2091 return 0;
2092
2093 if (! CLASS_TYPE_P (type))
2094 {
2095 if (or_else)
2096 error ("%qT is not a class type", type);
2097 return 0;
2098 }
2099 return 1;
2100 }
2101
2102 tree
get_type_value(tree name)2103 get_type_value (tree name)
2104 {
2105 if (name == error_mark_node)
2106 return NULL_TREE;
2107
2108 if (IDENTIFIER_HAS_TYPE_VALUE (name))
2109 return IDENTIFIER_TYPE_VALUE (name);
2110 else
2111 return NULL_TREE;
2112 }
2113
2114 /* Build a reference to a member of an aggregate. This is not a C++
2115 `&', but really something which can have its address taken, and
2116 then act as a pointer to member, for example TYPE :: FIELD can have
2117 its address taken by saying & TYPE :: FIELD. ADDRESS_P is true if
2118 this expression is the operand of "&".
2119
2120 @@ Prints out lousy diagnostics for operator <typename>
2121 @@ fields.
2122
2123 @@ This function should be rewritten and placed in search.c. */
2124
2125 tree
build_offset_ref(tree type,tree member,bool address_p,tsubst_flags_t complain)2126 build_offset_ref (tree type, tree member, bool address_p,
2127 tsubst_flags_t complain)
2128 {
2129 tree decl;
2130 tree basebinfo = NULL_TREE;
2131
2132 /* class templates can come in as TEMPLATE_DECLs here. */
2133 if (TREE_CODE (member) == TEMPLATE_DECL)
2134 return member;
2135
2136 if (dependent_scope_p (type) || type_dependent_expression_p (member))
2137 return build_qualified_name (NULL_TREE, type, member,
2138 /*template_p=*/false);
2139
2140 gcc_assert (TYPE_P (type));
2141 if (! is_class_type (type, 1))
2142 return error_mark_node;
2143
2144 gcc_assert (DECL_P (member) || BASELINK_P (member));
2145 /* Callers should call mark_used before this point. */
2146 gcc_assert (!DECL_P (member) || TREE_USED (member));
2147
2148 type = TYPE_MAIN_VARIANT (type);
2149 if (!COMPLETE_OR_OPEN_TYPE_P (complete_type (type)))
2150 {
2151 if (complain & tf_error)
2152 error ("incomplete type %qT does not have member %qD", type, member);
2153 return error_mark_node;
2154 }
2155
2156 /* Entities other than non-static members need no further
2157 processing. */
2158 if (TREE_CODE (member) == TYPE_DECL)
2159 return member;
2160 if (VAR_P (member) || TREE_CODE (member) == CONST_DECL)
2161 return convert_from_reference (member);
2162
2163 if (TREE_CODE (member) == FIELD_DECL && DECL_C_BIT_FIELD (member))
2164 {
2165 if (complain & tf_error)
2166 error ("invalid pointer to bit-field %qD", member);
2167 return error_mark_node;
2168 }
2169
2170 /* Set up BASEBINFO for member lookup. */
2171 decl = maybe_dummy_object (type, &basebinfo);
2172
2173 /* A lot of this logic is now handled in lookup_member. */
2174 if (BASELINK_P (member))
2175 {
2176 /* Go from the TREE_BASELINK to the member function info. */
2177 tree t = BASELINK_FUNCTIONS (member);
2178
2179 if (TREE_CODE (t) != TEMPLATE_ID_EXPR && !really_overloaded_fn (t))
2180 {
2181 /* Get rid of a potential OVERLOAD around it. */
2182 t = OVL_FIRST (t);
2183
2184 /* Unique functions are handled easily. */
2185
2186 /* For non-static member of base class, we need a special rule
2187 for access checking [class.protected]:
2188
2189 If the access is to form a pointer to member, the
2190 nested-name-specifier shall name the derived class
2191 (or any class derived from that class). */
2192 bool ok;
2193 if (address_p && DECL_P (t)
2194 && DECL_NONSTATIC_MEMBER_P (t))
2195 ok = perform_or_defer_access_check (TYPE_BINFO (type), t, t,
2196 complain);
2197 else
2198 ok = perform_or_defer_access_check (basebinfo, t, t,
2199 complain);
2200 if (!ok)
2201 return error_mark_node;
2202 if (DECL_STATIC_FUNCTION_P (t))
2203 return t;
2204 member = t;
2205 }
2206 else
2207 TREE_TYPE (member) = unknown_type_node;
2208 }
2209 else if (address_p && TREE_CODE (member) == FIELD_DECL)
2210 {
2211 /* We need additional test besides the one in
2212 check_accessibility_of_qualified_id in case it is
2213 a pointer to non-static member. */
2214 if (!perform_or_defer_access_check (TYPE_BINFO (type), member, member,
2215 complain))
2216 return error_mark_node;
2217 }
2218
2219 if (!address_p)
2220 {
2221 /* If MEMBER is non-static, then the program has fallen afoul of
2222 [expr.prim]:
2223
2224 An id-expression that denotes a nonstatic data member or
2225 nonstatic member function of a class can only be used:
2226
2227 -- as part of a class member access (_expr.ref_) in which the
2228 object-expression refers to the member's class or a class
2229 derived from that class, or
2230
2231 -- to form a pointer to member (_expr.unary.op_), or
2232
2233 -- in the body of a nonstatic member function of that class or
2234 of a class derived from that class (_class.mfct.nonstatic_), or
2235
2236 -- in a mem-initializer for a constructor for that class or for
2237 a class derived from that class (_class.base.init_). */
2238 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (member))
2239 {
2240 /* Build a representation of the qualified name suitable
2241 for use as the operand to "&" -- even though the "&" is
2242 not actually present. */
2243 member = build2 (OFFSET_REF, TREE_TYPE (member), decl, member);
2244 /* In Microsoft mode, treat a non-static member function as if
2245 it were a pointer-to-member. */
2246 if (flag_ms_extensions)
2247 {
2248 PTRMEM_OK_P (member) = 1;
2249 return cp_build_addr_expr (member, complain);
2250 }
2251 if (complain & tf_error)
2252 error ("invalid use of non-static member function %qD",
2253 TREE_OPERAND (member, 1));
2254 return error_mark_node;
2255 }
2256 else if (TREE_CODE (member) == FIELD_DECL)
2257 {
2258 if (complain & tf_error)
2259 error ("invalid use of non-static data member %qD", member);
2260 return error_mark_node;
2261 }
2262 return member;
2263 }
2264
2265 member = build2 (OFFSET_REF, TREE_TYPE (member), decl, member);
2266 PTRMEM_OK_P (member) = 1;
2267 return member;
2268 }
2269
2270 /* If DECL is a scalar enumeration constant or variable with a
2271 constant initializer, return the initializer (or, its initializers,
2272 recursively); otherwise, return DECL. If STRICT_P, the
2273 initializer is only returned if DECL is a
2274 constant-expression. If RETURN_AGGREGATE_CST_OK_P, it is ok to
2275 return an aggregate constant. If UNSHARE_P, return an unshared
2276 copy of the initializer. */
2277
2278 static tree
constant_value_1(tree decl,bool strict_p,bool return_aggregate_cst_ok_p,bool unshare_p)2279 constant_value_1 (tree decl, bool strict_p, bool return_aggregate_cst_ok_p,
2280 bool unshare_p)
2281 {
2282 while (TREE_CODE (decl) == CONST_DECL
2283 || decl_constant_var_p (decl)
2284 || (!strict_p && VAR_P (decl)
2285 && CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (decl))))
2286 {
2287 tree init;
2288 /* If DECL is a static data member in a template
2289 specialization, we must instantiate it here. The
2290 initializer for the static data member is not processed
2291 until needed; we need it now. */
2292 mark_used (decl, tf_none);
2293 init = DECL_INITIAL (decl);
2294 if (init == error_mark_node)
2295 {
2296 if (TREE_CODE (decl) == CONST_DECL
2297 || DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
2298 /* Treat the error as a constant to avoid cascading errors on
2299 excessively recursive template instantiation (c++/9335). */
2300 return init;
2301 else
2302 return decl;
2303 }
2304 /* Initializers in templates are generally expanded during
2305 instantiation, so before that for const int i(2)
2306 INIT is a TREE_LIST with the actual initializer as
2307 TREE_VALUE. */
2308 if (processing_template_decl
2309 && init
2310 && TREE_CODE (init) == TREE_LIST
2311 && TREE_CHAIN (init) == NULL_TREE)
2312 init = TREE_VALUE (init);
2313 /* Instantiate a non-dependent initializer for user variables. We
2314 mustn't do this for the temporary for an array compound literal;
2315 trying to instatiate the initializer will keep creating new
2316 temporaries until we crash. Probably it's not useful to do it for
2317 other artificial variables, either. */
2318 if (!DECL_ARTIFICIAL (decl))
2319 init = instantiate_non_dependent_or_null (init);
2320 if (!init
2321 || !TREE_TYPE (init)
2322 || !TREE_CONSTANT (init)
2323 || (!return_aggregate_cst_ok_p
2324 /* Unless RETURN_AGGREGATE_CST_OK_P is true, do not
2325 return an aggregate constant (of which string
2326 literals are a special case), as we do not want
2327 to make inadvertent copies of such entities, and
2328 we must be sure that their addresses are the
2329 same everywhere. */
2330 && (TREE_CODE (init) == CONSTRUCTOR
2331 || TREE_CODE (init) == STRING_CST)))
2332 break;
2333 /* Don't return a CONSTRUCTOR for a variable with partial run-time
2334 initialization, since it doesn't represent the entire value.
2335 Similarly for VECTOR_CSTs created by cp_folding those
2336 CONSTRUCTORs. */
2337 if ((TREE_CODE (init) == CONSTRUCTOR
2338 || TREE_CODE (init) == VECTOR_CST)
2339 && !DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
2340 break;
2341 /* If the variable has a dynamic initializer, don't use its
2342 DECL_INITIAL which doesn't reflect the real value. */
2343 if (VAR_P (decl)
2344 && TREE_STATIC (decl)
2345 && !DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)
2346 && DECL_NONTRIVIALLY_INITIALIZED_P (decl))
2347 break;
2348 decl = init;
2349 }
2350 return unshare_p ? unshare_expr (decl) : decl;
2351 }
2352
2353 /* If DECL is a CONST_DECL, or a constant VAR_DECL initialized by constant
2354 of integral or enumeration type, or a constexpr variable of scalar type,
2355 then return that value. These are those variables permitted in constant
2356 expressions by [5.19/1]. */
2357
2358 tree
scalar_constant_value(tree decl)2359 scalar_constant_value (tree decl)
2360 {
2361 return constant_value_1 (decl, /*strict_p=*/true,
2362 /*return_aggregate_cst_ok_p=*/false,
2363 /*unshare_p=*/true);
2364 }
2365
2366 /* Like scalar_constant_value, but can also return aggregate initializers.
2367 If UNSHARE_P, return an unshared copy of the initializer. */
2368
2369 tree
decl_really_constant_value(tree decl,bool unshare_p)2370 decl_really_constant_value (tree decl, bool unshare_p /*= true*/)
2371 {
2372 return constant_value_1 (decl, /*strict_p=*/true,
2373 /*return_aggregate_cst_ok_p=*/true,
2374 /*unshare_p=*/unshare_p);
2375 }
2376
2377 /* A more relaxed version of decl_really_constant_value, used by the
2378 common C/C++ code. */
2379
2380 tree
decl_constant_value(tree decl,bool unshare_p)2381 decl_constant_value (tree decl, bool unshare_p)
2382 {
2383 return constant_value_1 (decl, /*strict_p=*/processing_template_decl,
2384 /*return_aggregate_cst_ok_p=*/true,
2385 /*unshare_p=*/unshare_p);
2386 }
2387
2388 tree
decl_constant_value(tree decl)2389 decl_constant_value (tree decl)
2390 {
2391 return decl_constant_value (decl, /*unshare_p=*/true);
2392 }
2393
2394 /* Common subroutines of build_new and build_vec_delete. */
2395
2396 /* Build and return a NEW_EXPR. If NELTS is non-NULL, TYPE[NELTS] is
2397 the type of the object being allocated; otherwise, it's just TYPE.
2398 INIT is the initializer, if any. USE_GLOBAL_NEW is true if the
2399 user explicitly wrote "::operator new". PLACEMENT, if non-NULL, is
2400 a vector of arguments to be provided as arguments to a placement
2401 new operator. This routine performs no semantic checks; it just
2402 creates and returns a NEW_EXPR. */
2403
2404 static tree
build_raw_new_expr(location_t loc,vec<tree,va_gc> * placement,tree type,tree nelts,vec<tree,va_gc> * init,int use_global_new)2405 build_raw_new_expr (location_t loc, vec<tree, va_gc> *placement, tree type,
2406 tree nelts, vec<tree, va_gc> *init, int use_global_new)
2407 {
2408 tree init_list;
2409 tree new_expr;
2410
2411 /* If INIT is NULL, the we want to store NULL_TREE in the NEW_EXPR.
2412 If INIT is not NULL, then we want to store VOID_ZERO_NODE. This
2413 permits us to distinguish the case of a missing initializer "new
2414 int" from an empty initializer "new int()". */
2415 if (init == NULL)
2416 init_list = NULL_TREE;
2417 else if (init->is_empty ())
2418 init_list = void_node;
2419 else
2420 init_list = build_tree_list_vec (init);
2421
2422 new_expr = build4_loc (loc, NEW_EXPR, build_pointer_type (type),
2423 build_tree_list_vec (placement), type, nelts,
2424 init_list);
2425 NEW_EXPR_USE_GLOBAL (new_expr) = use_global_new;
2426 TREE_SIDE_EFFECTS (new_expr) = 1;
2427
2428 return new_expr;
2429 }
2430
2431 /* Diagnose uninitialized const members or reference members of type
2432 TYPE. USING_NEW is used to disambiguate the diagnostic between a
2433 new expression without a new-initializer and a declaration. Returns
2434 the error count. */
2435
2436 static int
diagnose_uninitialized_cst_or_ref_member_1(tree type,tree origin,bool using_new,bool complain)2437 diagnose_uninitialized_cst_or_ref_member_1 (tree type, tree origin,
2438 bool using_new, bool complain)
2439 {
2440 tree field;
2441 int error_count = 0;
2442
2443 if (type_has_user_provided_constructor (type))
2444 return 0;
2445
2446 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
2447 {
2448 tree field_type;
2449
2450 if (TREE_CODE (field) != FIELD_DECL)
2451 continue;
2452
2453 field_type = strip_array_types (TREE_TYPE (field));
2454
2455 if (type_has_user_provided_constructor (field_type))
2456 continue;
2457
2458 if (TYPE_REF_P (field_type))
2459 {
2460 ++ error_count;
2461 if (complain)
2462 {
2463 if (DECL_CONTEXT (field) == origin)
2464 {
2465 if (using_new)
2466 error ("uninitialized reference member in %q#T "
2467 "using %<new%> without new-initializer", origin);
2468 else
2469 error ("uninitialized reference member in %q#T", origin);
2470 }
2471 else
2472 {
2473 if (using_new)
2474 error ("uninitialized reference member in base %q#T "
2475 "of %q#T using %<new%> without new-initializer",
2476 DECL_CONTEXT (field), origin);
2477 else
2478 error ("uninitialized reference member in base %q#T "
2479 "of %q#T", DECL_CONTEXT (field), origin);
2480 }
2481 inform (DECL_SOURCE_LOCATION (field),
2482 "%q#D should be initialized", field);
2483 }
2484 }
2485
2486 if (CP_TYPE_CONST_P (field_type))
2487 {
2488 ++ error_count;
2489 if (complain)
2490 {
2491 if (DECL_CONTEXT (field) == origin)
2492 {
2493 if (using_new)
2494 error ("uninitialized const member in %q#T "
2495 "using %<new%> without new-initializer", origin);
2496 else
2497 error ("uninitialized const member in %q#T", origin);
2498 }
2499 else
2500 {
2501 if (using_new)
2502 error ("uninitialized const member in base %q#T "
2503 "of %q#T using %<new%> without new-initializer",
2504 DECL_CONTEXT (field), origin);
2505 else
2506 error ("uninitialized const member in base %q#T "
2507 "of %q#T", DECL_CONTEXT (field), origin);
2508 }
2509 inform (DECL_SOURCE_LOCATION (field),
2510 "%q#D should be initialized", field);
2511 }
2512 }
2513
2514 if (CLASS_TYPE_P (field_type))
2515 error_count
2516 += diagnose_uninitialized_cst_or_ref_member_1 (field_type, origin,
2517 using_new, complain);
2518 }
2519 return error_count;
2520 }
2521
2522 int
diagnose_uninitialized_cst_or_ref_member(tree type,bool using_new,bool complain)2523 diagnose_uninitialized_cst_or_ref_member (tree type, bool using_new, bool complain)
2524 {
2525 return diagnose_uninitialized_cst_or_ref_member_1 (type, type, using_new, complain);
2526 }
2527
2528 /* Call __cxa_bad_array_new_length to indicate that the size calculation
2529 overflowed. Pretend it returns sizetype so that it plays nicely in the
2530 COND_EXPR. */
2531
2532 tree
throw_bad_array_new_length(void)2533 throw_bad_array_new_length (void)
2534 {
2535 if (!fn)
2536 {
2537 tree name = get_identifier ("__cxa_throw_bad_array_new_length");
2538
2539 fn = get_global_binding (name);
2540 if (!fn)
2541 fn = push_throw_library_fn
2542 (name, build_function_type_list (sizetype, NULL_TREE));
2543 }
2544
2545 return build_cxx_call (fn, 0, NULL, tf_warning_or_error);
2546 }
2547
2548 /* Attempt to find the initializer for flexible array field T in the
2549 initializer INIT, when non-null. Returns the initializer when
2550 successful and NULL otherwise. */
2551 static tree
find_flexarray_init(tree t,tree init)2552 find_flexarray_init (tree t, tree init)
2553 {
2554 if (!init || init == error_mark_node)
2555 return NULL_TREE;
2556
2557 unsigned HOST_WIDE_INT idx;
2558 tree field, elt;
2559
2560 /* Iterate over all top-level initializer elements. */
2561 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init), idx, field, elt)
2562 /* If the member T is found, return it. */
2563 if (field == t)
2564 return elt;
2565
2566 return NULL_TREE;
2567 }
2568
2569 /* Attempt to verify that the argument, OPER, of a placement new expression
2570 refers to an object sufficiently large for an object of TYPE or an array
2571 of NELTS of such objects when NELTS is non-null, and issue a warning when
2572 it does not. SIZE specifies the size needed to construct the object or
2573 array and captures the result of NELTS * sizeof (TYPE). (SIZE could be
2574 greater when the array under construction requires a cookie to store
2575 NELTS. GCC's placement new expression stores the cookie when invoking
2576 a user-defined placement new operator function but not the default one.
2577 Placement new expressions with user-defined placement new operator are
2578 not diagnosed since we don't know how they use the buffer (this could
2579 be a future extension). */
2580 static void
warn_placement_new_too_small(tree type,tree nelts,tree size,tree oper)2581 warn_placement_new_too_small (tree type, tree nelts, tree size, tree oper)
2582 {
2583 location_t loc = cp_expr_loc_or_input_loc (oper);
2584
2585 /* The number of bytes to add to or subtract from the size of the provided
2586 buffer based on an offset into an array or an array element reference.
2587 Although intermediate results may be negative (as in a[3] - 2) a valid
2588 final result cannot be. */
2589 offset_int adjust = 0;
2590 /* True when the size of the entire destination object should be used
2591 to compute the possibly optimistic estimate of the available space. */
2592 bool use_obj_size = false;
2593 /* True when the reference to the destination buffer is an ADDR_EXPR. */
2594 bool addr_expr = false;
2595
2596 STRIP_NOPS (oper);
2597
2598 /* Using a function argument or a (non-array) variable as an argument
2599 to placement new is not checked since it's unknown what it might
2600 point to. */
2601 if (TREE_CODE (oper) == PARM_DECL
2602 || VAR_P (oper)
2603 || TREE_CODE (oper) == COMPONENT_REF)
2604 return;
2605
2606 /* Evaluate any constant expressions. */
2607 size = fold_non_dependent_expr (size);
2608
2609 /* Handle the common case of array + offset expression when the offset
2610 is a constant. */
2611 if (TREE_CODE (oper) == POINTER_PLUS_EXPR)
2612 {
2613 /* If the offset is compile-time constant, use it to compute a more
2614 accurate estimate of the size of the buffer. Since the operand
2615 of POINTER_PLUS_EXPR is represented as an unsigned type, convert
2616 it to signed first.
2617 Otherwise, use the size of the entire array as an optimistic
2618 estimate (this may lead to false negatives). */
2619 tree adj = TREE_OPERAND (oper, 1);
2620 adj = fold_for_warn (adj);
2621 if (CONSTANT_CLASS_P (adj))
2622 adjust += wi::to_offset (convert (ssizetype, adj));
2623 else
2624 use_obj_size = true;
2625
2626 oper = TREE_OPERAND (oper, 0);
2627
2628 STRIP_NOPS (oper);
2629 }
2630
2631 if (TREE_CODE (oper) == TARGET_EXPR)
2632 oper = TREE_OPERAND (oper, 1);
2633 else if (TREE_CODE (oper) == ADDR_EXPR)
2634 {
2635 addr_expr = true;
2636 oper = TREE_OPERAND (oper, 0);
2637 }
2638
2639 STRIP_NOPS (oper);
2640
2641 if (TREE_CODE (oper) == ARRAY_REF
2642 && (addr_expr || TREE_CODE (TREE_TYPE (oper)) == ARRAY_TYPE))
2643 {
2644 /* Similar to the offset computed above, see if the array index
2645 is a compile-time constant. If so, and unless the offset was
2646 not a compile-time constant, use the index to determine the
2647 size of the buffer. Otherwise, use the entire array as
2648 an optimistic estimate of the size. */
2649 const_tree adj = fold_non_dependent_expr (TREE_OPERAND (oper, 1));
2650 if (!use_obj_size && CONSTANT_CLASS_P (adj))
2651 adjust += wi::to_offset (adj);
2652 else
2653 {
2654 use_obj_size = true;
2655 adjust = 0;
2656 }
2657
2658 oper = TREE_OPERAND (oper, 0);
2659 }
2660
2661 /* Refers to the declared object that constains the subobject referenced
2662 by OPER. When the object is initialized, makes it possible to determine
2663 the actual size of a flexible array member used as the buffer passed
2664 as OPER to placement new. */
2665 tree var_decl = NULL_TREE;
2666 /* True when operand is a COMPONENT_REF, to distinguish flexible array
2667 members from arrays of unspecified size. */
2668 bool compref = TREE_CODE (oper) == COMPONENT_REF;
2669
2670 /* For COMPONENT_REF (i.e., a struct member) the size of the entire
2671 enclosing struct. Used to validate the adjustment (offset) into
2672 an array at the end of a struct. */
2673 offset_int compsize = 0;
2674
2675 /* Descend into a struct or union to find the member whose address
2676 is being used as the argument. */
2677 if (TREE_CODE (oper) == COMPONENT_REF)
2678 {
2679 tree comptype = TREE_TYPE (TREE_OPERAND (oper, 0));
2680 compsize = wi::to_offset (TYPE_SIZE_UNIT (comptype));
2681
2682 tree op0 = oper;
2683 while (TREE_CODE (op0 = TREE_OPERAND (op0, 0)) == COMPONENT_REF);
2684 STRIP_ANY_LOCATION_WRAPPER (op0);
2685 if (VAR_P (op0))
2686 var_decl = op0;
2687 oper = TREE_OPERAND (oper, 1);
2688 }
2689
2690 STRIP_ANY_LOCATION_WRAPPER (oper);
2691 tree opertype = TREE_TYPE (oper);
2692 if ((addr_expr || !INDIRECT_TYPE_P (opertype))
2693 && (VAR_P (oper)
2694 || TREE_CODE (oper) == FIELD_DECL
2695 || TREE_CODE (oper) == PARM_DECL))
2696 {
2697 /* A possibly optimistic estimate of the number of bytes available
2698 in the destination buffer. */
2699 offset_int bytes_avail = 0;
2700 /* True when the estimate above is in fact the exact size
2701 of the destination buffer rather than an estimate. */
2702 bool exact_size = true;
2703
2704 /* Treat members of unions and members of structs uniformly, even
2705 though the size of a member of a union may be viewed as extending
2706 to the end of the union itself (it is by __builtin_object_size). */
2707 if ((VAR_P (oper) || use_obj_size)
2708 && DECL_SIZE_UNIT (oper)
2709 && tree_fits_uhwi_p (DECL_SIZE_UNIT (oper)))
2710 {
2711 /* Use the size of the entire array object when the expression
2712 refers to a variable or its size depends on an expression
2713 that's not a compile-time constant. */
2714 bytes_avail = wi::to_offset (DECL_SIZE_UNIT (oper));
2715 exact_size = !use_obj_size;
2716 }
2717 else if (tree opersize = TYPE_SIZE_UNIT (opertype))
2718 {
2719 /* Use the size of the type of the destination buffer object
2720 as the optimistic estimate of the available space in it.
2721 Use the maximum possible size for zero-size arrays and
2722 flexible array members (except of initialized objects
2723 thereof). */
2724 if (TREE_CODE (opersize) == INTEGER_CST)
2725 bytes_avail = wi::to_offset (opersize);
2726 }
2727
2728 if (bytes_avail == 0)
2729 {
2730 if (var_decl)
2731 {
2732 /* Constructing into a buffer provided by the flexible array
2733 member of a declared object (which is permitted as a G++
2734 extension). If the array member has been initialized,
2735 determine its size from the initializer. Otherwise,
2736 the array size is zero. */
2737 if (tree init = find_flexarray_init (oper,
2738 DECL_INITIAL (var_decl)))
2739 bytes_avail = wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (init)));
2740 }
2741 else
2742 bytes_avail = (wi::to_offset (TYPE_MAX_VALUE (ptrdiff_type_node))
2743 - compsize);
2744 }
2745
2746 tree_code oper_code = TREE_CODE (opertype);
2747
2748 if (compref && oper_code == ARRAY_TYPE)
2749 {
2750 tree nelts = array_type_nelts_top (opertype);
2751 tree nelts_cst = maybe_constant_value (nelts);
2752 if (TREE_CODE (nelts_cst) == INTEGER_CST
2753 && integer_onep (nelts_cst)
2754 && !var_decl
2755 && warn_placement_new < 2)
2756 return;
2757 }
2758
2759 /* Reduce the size of the buffer by the adjustment computed above
2760 from the offset and/or the index into the array. */
2761 if (bytes_avail < adjust || adjust < 0)
2762 bytes_avail = 0;
2763 else
2764 {
2765 tree elttype = (TREE_CODE (opertype) == ARRAY_TYPE
2766 ? TREE_TYPE (opertype) : opertype);
2767 if (tree eltsize = TYPE_SIZE_UNIT (elttype))
2768 {
2769 bytes_avail -= adjust * wi::to_offset (eltsize);
2770 if (bytes_avail < 0)
2771 bytes_avail = 0;
2772 }
2773 }
2774
2775 /* The minimum amount of space needed for the allocation. This
2776 is an optimistic estimate that makes it possible to detect
2777 placement new invocation for some undersize buffers but not
2778 others. */
2779 offset_int bytes_need;
2780
2781 if (nelts)
2782 nelts = fold_for_warn (nelts);
2783
2784 if (CONSTANT_CLASS_P (size))
2785 bytes_need = wi::to_offset (size);
2786 else if (nelts && CONSTANT_CLASS_P (nelts))
2787 bytes_need = (wi::to_offset (nelts)
2788 * wi::to_offset (TYPE_SIZE_UNIT (type)));
2789 else if (tree_fits_uhwi_p (TYPE_SIZE_UNIT (type)))
2790 bytes_need = wi::to_offset (TYPE_SIZE_UNIT (type));
2791 else
2792 {
2793 /* The type is a VLA. */
2794 return;
2795 }
2796
2797 if (bytes_avail < bytes_need)
2798 {
2799 if (nelts)
2800 if (CONSTANT_CLASS_P (nelts))
2801 warning_at (loc, OPT_Wplacement_new_,
2802 exact_size ?
2803 "placement new constructing an object of type "
2804 "%<%T [%wu]%> and size %qwu in a region of type %qT "
2805 "and size %qwi"
2806 : "placement new constructing an object of type "
2807 "%<%T [%wu]%> and size %qwu in a region of type %qT "
2808 "and size at most %qwu",
2809 type, tree_to_uhwi (nelts), bytes_need.to_uhwi (),
2810 opertype, bytes_avail.to_uhwi ());
2811 else
2812 warning_at (loc, OPT_Wplacement_new_,
2813 exact_size ?
2814 "placement new constructing an array of objects "
2815 "of type %qT and size %qwu in a region of type %qT "
2816 "and size %qwi"
2817 : "placement new constructing an array of objects "
2818 "of type %qT and size %qwu in a region of type %qT "
2819 "and size at most %qwu",
2820 type, bytes_need.to_uhwi (), opertype,
2821 bytes_avail.to_uhwi ());
2822 else
2823 warning_at (loc, OPT_Wplacement_new_,
2824 exact_size ?
2825 "placement new constructing an object of type %qT "
2826 "and size %qwu in a region of type %qT and size %qwi"
2827 : "placement new constructing an object of type %qT "
2828 "and size %qwu in a region of type %qT and size "
2829 "at most %qwu",
2830 type, bytes_need.to_uhwi (), opertype,
2831 bytes_avail.to_uhwi ());
2832 }
2833 }
2834 }
2835
2836 /* True if alignof(T) > __STDCPP_DEFAULT_NEW_ALIGNMENT__. */
2837
2838 bool
type_has_new_extended_alignment(tree t)2839 type_has_new_extended_alignment (tree t)
2840 {
2841 return (aligned_new_threshold
2842 && TYPE_ALIGN_UNIT (t) > (unsigned)aligned_new_threshold);
2843 }
2844
2845 /* Return the alignment we expect malloc to guarantee. This should just be
2846 MALLOC_ABI_ALIGNMENT, but that macro defaults to only BITS_PER_WORD for some
2847 reason, so don't let the threshold be smaller than max_align_t_align. */
2848
2849 unsigned
malloc_alignment()2850 malloc_alignment ()
2851 {
2852 return MAX (max_align_t_align(), MALLOC_ABI_ALIGNMENT);
2853 }
2854
2855 /* Determine whether an allocation function is a namespace-scope
2856 non-replaceable placement new function. See DR 1748. */
2857 static bool
std_placement_new_fn_p(tree alloc_fn)2858 std_placement_new_fn_p (tree alloc_fn)
2859 {
2860 if (DECL_NAMESPACE_SCOPE_P (alloc_fn))
2861 {
2862 tree first_arg = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
2863 if ((TREE_VALUE (first_arg) == ptr_type_node)
2864 && TREE_CHAIN (first_arg) == void_list_node)
2865 return true;
2866 }
2867 return false;
2868 }
2869
2870 /* For element type ELT_TYPE, return the appropriate type of the heap object
2871 containing such element(s). COOKIE_SIZE is NULL or the size of cookie
2872 in bytes. FULL_SIZE is NULL if it is unknown how big the heap allocation
2873 will be, otherwise size of the heap object. If COOKIE_SIZE is NULL,
2874 return array type ELT_TYPE[FULL_SIZE / sizeof(ELT_TYPE)], otherwise return
2875 struct { size_t[COOKIE_SIZE/sizeof(size_t)]; ELT_TYPE[N]; }
2876 where N is nothing (flexible array member) if FULL_SIZE is NULL, otherwise
2877 it is computed such that the size of the struct fits into FULL_SIZE. */
2878
2879 tree
build_new_constexpr_heap_type(tree elt_type,tree cookie_size,tree full_size)2880 build_new_constexpr_heap_type (tree elt_type, tree cookie_size, tree full_size)
2881 {
2882 gcc_assert (cookie_size == NULL_TREE || tree_fits_uhwi_p (cookie_size));
2883 gcc_assert (full_size == NULL_TREE || tree_fits_uhwi_p (full_size));
2884 unsigned HOST_WIDE_INT csz = cookie_size ? tree_to_uhwi (cookie_size) : 0;
2885 tree itype2 = NULL_TREE;
2886 if (full_size)
2887 {
2888 unsigned HOST_WIDE_INT fsz = tree_to_uhwi (full_size);
2889 gcc_assert (fsz >= csz);
2890 fsz -= csz;
2891 fsz /= int_size_in_bytes (elt_type);
2892 itype2 = build_index_type (size_int (fsz - 1));
2893 if (!cookie_size)
2894 return build_cplus_array_type (elt_type, itype2);
2895 }
2896 else
2897 gcc_assert (cookie_size);
2898 csz /= int_size_in_bytes (sizetype);
2899 tree itype1 = build_index_type (size_int (csz - 1));
2900 tree atype1 = build_cplus_array_type (sizetype, itype1);
2901 tree atype2 = build_cplus_array_type (elt_type, itype2);
2902 tree rtype = cxx_make_type (RECORD_TYPE);
2903 TYPE_NAME (rtype) = heap_identifier;
2904 tree fld1 = build_decl (UNKNOWN_LOCATION, FIELD_DECL, NULL_TREE, atype1);
2905 tree fld2 = build_decl (UNKNOWN_LOCATION, FIELD_DECL, NULL_TREE, atype2);
2906 DECL_FIELD_CONTEXT (fld1) = rtype;
2907 DECL_FIELD_CONTEXT (fld2) = rtype;
2908 DECL_ARTIFICIAL (fld1) = true;
2909 DECL_ARTIFICIAL (fld2) = true;
2910 TYPE_FIELDS (rtype) = fld1;
2911 DECL_CHAIN (fld1) = fld2;
2912 layout_type (rtype);
2913 return rtype;
2914 }
2915
2916 /* Help the constexpr code to find the right type for the heap variable
2917 by adding a NOP_EXPR around ALLOC_CALL if needed for cookie_size.
2918 Return ALLOC_CALL or ALLOC_CALL cast to a pointer to
2919 struct { size_t[cookie_size/sizeof(size_t)]; elt_type[]; }. */
2920
2921 static tree
maybe_wrap_new_for_constexpr(tree alloc_call,tree elt_type,tree cookie_size)2922 maybe_wrap_new_for_constexpr (tree alloc_call, tree elt_type, tree cookie_size)
2923 {
2924 if (cxx_dialect < cxx2a)
2925 return alloc_call;
2926
2927 if (current_function_decl != NULL_TREE
2928 && !DECL_DECLARED_CONSTEXPR_P (current_function_decl))
2929 return alloc_call;
2930
2931 tree call_expr = extract_call_expr (alloc_call);
2932 if (call_expr == error_mark_node)
2933 return alloc_call;
2934
2935 tree alloc_call_fndecl = cp_get_callee_fndecl_nofold (call_expr);
2936 if (alloc_call_fndecl == NULL_TREE
2937 || !IDENTIFIER_NEW_OP_P (DECL_NAME (alloc_call_fndecl))
2938 || CP_DECL_CONTEXT (alloc_call_fndecl) != global_namespace)
2939 return alloc_call;
2940
2941 tree rtype = build_new_constexpr_heap_type (elt_type, cookie_size,
2942 NULL_TREE);
2943 return build_nop (build_pointer_type (rtype), alloc_call);
2944 }
2945
2946 /* Generate code for a new-expression, including calling the "operator
2947 new" function, initializing the object, and, if an exception occurs
2948 during construction, cleaning up. The arguments are as for
2949 build_raw_new_expr. This may change PLACEMENT and INIT.
2950 TYPE is the type of the object being constructed, possibly an array
2951 of NELTS elements when NELTS is non-null (in "new T[NELTS]", T may
2952 be an array of the form U[inner], with the whole expression being
2953 "new U[NELTS][inner]"). */
2954
2955 static tree
build_new_1(vec<tree,va_gc> ** placement,tree type,tree nelts,vec<tree,va_gc> ** init,bool globally_qualified_p,tsubst_flags_t complain)2956 build_new_1 (vec<tree, va_gc> **placement, tree type, tree nelts,
2957 vec<tree, va_gc> **init, bool globally_qualified_p,
2958 tsubst_flags_t complain)
2959 {
2960 tree size, rval;
2961 /* True iff this is a call to "operator new[]" instead of just
2962 "operator new". */
2963 bool array_p = false;
2964 /* If ARRAY_P is true, the element type of the array. This is never
2965 an ARRAY_TYPE; for something like "new int[3][4]", the
2966 ELT_TYPE is "int". If ARRAY_P is false, this is the same type as
2967 TYPE. */
2968 tree elt_type;
2969 /* The type of the new-expression. (This type is always a pointer
2970 type.) */
2971 tree pointer_type;
2972 tree non_const_pointer_type;
2973 /* The most significant array bound in int[OUTER_NELTS][inner]. */
2974 tree outer_nelts = NULL_TREE;
2975 /* For arrays with a non-constant number of elements, a bounds checks
2976 on the NELTS parameter to avoid integer overflow at runtime. */
2977 tree outer_nelts_check = NULL_TREE;
2978 bool outer_nelts_from_type = false;
2979 /* Number of the "inner" elements in "new T[OUTER_NELTS][inner]". */
2980 offset_int inner_nelts_count = 1;
2981 tree alloc_call, alloc_expr;
2982 /* Size of the inner array elements (those with constant dimensions). */
2983 offset_int inner_size;
2984 /* The address returned by the call to "operator new". This node is
2985 a VAR_DECL and is therefore reusable. */
2986 tree alloc_node;
2987 tree alloc_fn;
2988 tree cookie_expr, init_expr;
2989 int nothrow, check_new;
2990 /* If non-NULL, the number of extra bytes to allocate at the
2991 beginning of the storage allocated for an array-new expression in
2992 order to store the number of elements. */
2993 tree cookie_size = NULL_TREE;
2994 tree placement_first;
2995 tree placement_expr = NULL_TREE;
2996 /* True if the function we are calling is a placement allocation
2997 function. */
2998 bool placement_allocation_fn_p;
2999 /* True if the storage must be initialized, either by a constructor
3000 or due to an explicit new-initializer. */
3001 bool is_initialized;
3002 /* The address of the thing allocated, not including any cookie. In
3003 particular, if an array cookie is in use, DATA_ADDR is the
3004 address of the first array element. This node is a VAR_DECL, and
3005 is therefore reusable. */
3006 tree data_addr;
3007 tree init_preeval_expr = NULL_TREE;
3008 tree orig_type = type;
3009
3010 if (nelts)
3011 {
3012 outer_nelts = nelts;
3013 array_p = true;
3014 }
3015 else if (TREE_CODE (type) == ARRAY_TYPE)
3016 {
3017 /* Transforms new (T[N]) to new T[N]. The former is a GNU
3018 extension for variable N. (This also covers new T where T is
3019 a VLA typedef.) */
3020 array_p = true;
3021 nelts = array_type_nelts_top (type);
3022 outer_nelts = nelts;
3023 type = TREE_TYPE (type);
3024 outer_nelts_from_type = true;
3025 }
3026
3027 /* Lots of logic below depends on whether we have a constant number of
3028 elements, so go ahead and fold it now. */
3029 const_tree cst_outer_nelts = fold_non_dependent_expr (outer_nelts, complain);
3030
3031 /* If our base type is an array, then make sure we know how many elements
3032 it has. */
3033 for (elt_type = type;
3034 TREE_CODE (elt_type) == ARRAY_TYPE;
3035 elt_type = TREE_TYPE (elt_type))
3036 {
3037 tree inner_nelts = array_type_nelts_top (elt_type);
3038 tree inner_nelts_cst = maybe_constant_value (inner_nelts);
3039 if (TREE_CODE (inner_nelts_cst) == INTEGER_CST)
3040 {
3041 wi::overflow_type overflow;
3042 offset_int result = wi::mul (wi::to_offset (inner_nelts_cst),
3043 inner_nelts_count, SIGNED, &overflow);
3044 if (overflow)
3045 {
3046 if (complain & tf_error)
3047 error ("integer overflow in array size");
3048 nelts = error_mark_node;
3049 }
3050 inner_nelts_count = result;
3051 }
3052 else
3053 {
3054 if (complain & tf_error)
3055 {
3056 error_at (cp_expr_loc_or_input_loc (inner_nelts),
3057 "array size in new-expression must be constant");
3058 cxx_constant_value(inner_nelts);
3059 }
3060 nelts = error_mark_node;
3061 }
3062 if (nelts != error_mark_node)
3063 nelts = cp_build_binary_op (input_location,
3064 MULT_EXPR, nelts,
3065 inner_nelts_cst,
3066 complain);
3067 }
3068
3069 if (!verify_type_context (input_location, TCTX_ALLOCATION, elt_type,
3070 !(complain & tf_error)))
3071 return error_mark_node;
3072
3073 if (variably_modified_type_p (elt_type, NULL_TREE) && (complain & tf_error))
3074 {
3075 error ("variably modified type not allowed in new-expression");
3076 return error_mark_node;
3077 }
3078
3079 if (nelts == error_mark_node)
3080 return error_mark_node;
3081
3082 /* Warn if we performed the (T[N]) to T[N] transformation and N is
3083 variable. */
3084 if (outer_nelts_from_type
3085 && !TREE_CONSTANT (cst_outer_nelts))
3086 {
3087 if (complain & tf_warning_or_error)
3088 {
3089 pedwarn (cp_expr_loc_or_input_loc (outer_nelts), OPT_Wvla,
3090 typedef_variant_p (orig_type)
3091 ? G_("non-constant array new length must be specified "
3092 "directly, not by %<typedef%>")
3093 : G_("non-constant array new length must be specified "
3094 "without parentheses around the type-id"));
3095 }
3096 else
3097 return error_mark_node;
3098 }
3099
3100 if (VOID_TYPE_P (elt_type))
3101 {
3102 if (complain & tf_error)
3103 error ("invalid type %<void%> for %<new%>");
3104 return error_mark_node;
3105 }
3106
3107 if (is_std_init_list (elt_type))
3108 warning (OPT_Winit_list_lifetime,
3109 "%<new%> of %<initializer_list%> does not "
3110 "extend the lifetime of the underlying array");
3111
3112 if (abstract_virtuals_error_sfinae (ACU_NEW, elt_type, complain))
3113 return error_mark_node;
3114
3115 is_initialized = (type_build_ctor_call (elt_type) || *init != NULL);
3116
3117 if (*init == NULL && cxx_dialect < cxx11)
3118 {
3119 bool maybe_uninitialized_error = false;
3120 /* A program that calls for default-initialization [...] of an
3121 entity of reference type is ill-formed. */
3122 if (CLASSTYPE_REF_FIELDS_NEED_INIT (elt_type))
3123 maybe_uninitialized_error = true;
3124
3125 /* A new-expression that creates an object of type T initializes
3126 that object as follows:
3127 - If the new-initializer is omitted:
3128 -- If T is a (possibly cv-qualified) non-POD class type
3129 (or array thereof), the object is default-initialized (8.5).
3130 [...]
3131 -- Otherwise, the object created has indeterminate
3132 value. If T is a const-qualified type, or a (possibly
3133 cv-qualified) POD class type (or array thereof)
3134 containing (directly or indirectly) a member of
3135 const-qualified type, the program is ill-formed; */
3136
3137 if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (elt_type))
3138 maybe_uninitialized_error = true;
3139
3140 if (maybe_uninitialized_error
3141 && diagnose_uninitialized_cst_or_ref_member (elt_type,
3142 /*using_new=*/true,
3143 complain & tf_error))
3144 return error_mark_node;
3145 }
3146
3147 if (CP_TYPE_CONST_P (elt_type) && *init == NULL
3148 && default_init_uninitialized_part (elt_type))
3149 {
3150 if (complain & tf_error)
3151 error ("uninitialized const in %<new%> of %q#T", elt_type);
3152 return error_mark_node;
3153 }
3154
3155 size = size_in_bytes (elt_type);
3156 if (array_p)
3157 {
3158 /* Maximum available size in bytes. Half of the address space
3159 minus the cookie size. */
3160 offset_int max_size
3161 = wi::set_bit_in_zero <offset_int> (TYPE_PRECISION (sizetype) - 1);
3162 /* Maximum number of outer elements which can be allocated. */
3163 offset_int max_outer_nelts;
3164 tree max_outer_nelts_tree;
3165
3166 gcc_assert (TREE_CODE (size) == INTEGER_CST);
3167 cookie_size = targetm.cxx.get_cookie_size (elt_type);
3168 gcc_assert (TREE_CODE (cookie_size) == INTEGER_CST);
3169 gcc_checking_assert (wi::ltu_p (wi::to_offset (cookie_size), max_size));
3170 /* Unconditionally subtract the cookie size. This decreases the
3171 maximum object size and is safe even if we choose not to use
3172 a cookie after all. */
3173 max_size -= wi::to_offset (cookie_size);
3174 wi::overflow_type overflow;
3175 inner_size = wi::mul (wi::to_offset (size), inner_nelts_count, SIGNED,
3176 &overflow);
3177 if (overflow || wi::gtu_p (inner_size, max_size))
3178 {
3179 if (complain & tf_error)
3180 {
3181 cst_size_error error;
3182 if (overflow)
3183 error = cst_size_overflow;
3184 else
3185 {
3186 error = cst_size_too_big;
3187 size = size_binop (MULT_EXPR, size,
3188 wide_int_to_tree (sizetype,
3189 inner_nelts_count));
3190 size = cp_fully_fold (size);
3191 }
3192 invalid_array_size_error (input_location, error, size,
3193 /*name=*/NULL_TREE);
3194 }
3195 return error_mark_node;
3196 }
3197
3198 max_outer_nelts = wi::udiv_trunc (max_size, inner_size);
3199 max_outer_nelts_tree = wide_int_to_tree (sizetype, max_outer_nelts);
3200
3201 size = size_binop (MULT_EXPR, size, fold_convert (sizetype, nelts));
3202
3203 if (TREE_CODE (cst_outer_nelts) == INTEGER_CST)
3204 {
3205 if (tree_int_cst_lt (max_outer_nelts_tree, cst_outer_nelts))
3206 {
3207 /* When the array size is constant, check it at compile time
3208 to make sure it doesn't exceed the implementation-defined
3209 maximum, as required by C++ 14 (in C++ 11 this requirement
3210 isn't explicitly stated but it's enforced anyway -- see
3211 grokdeclarator in cp/decl.c). */
3212 if (complain & tf_error)
3213 {
3214 size = cp_fully_fold (size);
3215 invalid_array_size_error (input_location, cst_size_too_big,
3216 size, NULL_TREE);
3217 }
3218 return error_mark_node;
3219 }
3220 }
3221 else
3222 {
3223 /* When a runtime check is necessary because the array size
3224 isn't constant, keep only the top-most seven bits (starting
3225 with the most significant non-zero bit) of the maximum size
3226 to compare the array size against, to simplify encoding the
3227 constant maximum size in the instruction stream. */
3228
3229 unsigned shift = (max_outer_nelts.get_precision ()) - 7
3230 - wi::clz (max_outer_nelts);
3231 max_outer_nelts = (max_outer_nelts >> shift) << shift;
3232
3233 outer_nelts_check = fold_build2 (LE_EXPR, boolean_type_node,
3234 outer_nelts,
3235 max_outer_nelts_tree);
3236 }
3237 }
3238
3239 tree align_arg = NULL_TREE;
3240 if (type_has_new_extended_alignment (elt_type))
3241 align_arg = build_int_cst (align_type_node, TYPE_ALIGN_UNIT (elt_type));
3242
3243 alloc_fn = NULL_TREE;
3244
3245 /* If PLACEMENT is a single simple pointer type not passed by
3246 reference, prepare to capture it in a temporary variable. Do
3247 this now, since PLACEMENT will change in the calls below. */
3248 placement_first = NULL_TREE;
3249 if (vec_safe_length (*placement) == 1
3250 && (TYPE_PTR_P (TREE_TYPE ((**placement)[0]))))
3251 placement_first = (**placement)[0];
3252
3253 bool member_new_p = false;
3254
3255 /* Allocate the object. */
3256 tree fnname;
3257 tree fns;
3258
3259 fnname = ovl_op_identifier (false, array_p ? VEC_NEW_EXPR : NEW_EXPR);
3260
3261 member_new_p = !globally_qualified_p
3262 && CLASS_TYPE_P (elt_type)
3263 && (array_p
3264 ? TYPE_HAS_ARRAY_NEW_OPERATOR (elt_type)
3265 : TYPE_HAS_NEW_OPERATOR (elt_type));
3266
3267 if (member_new_p)
3268 {
3269 /* Use a class-specific operator new. */
3270 /* If a cookie is required, add some extra space. */
3271 if (array_p && TYPE_VEC_NEW_USES_COOKIE (elt_type))
3272 size = size_binop (PLUS_EXPR, size, cookie_size);
3273 else
3274 {
3275 cookie_size = NULL_TREE;
3276 /* No size arithmetic necessary, so the size check is
3277 not needed. */
3278 if (outer_nelts_check != NULL && inner_size == 1)
3279 outer_nelts_check = NULL_TREE;
3280 }
3281 /* Perform the overflow check. */
3282 tree errval = TYPE_MAX_VALUE (sizetype);
3283 if (cxx_dialect >= cxx11 && flag_exceptions)
3284 errval = throw_bad_array_new_length ();
3285 if (outer_nelts_check != NULL_TREE)
3286 size = fold_build3 (COND_EXPR, sizetype, outer_nelts_check,
3287 size, errval);
3288 /* Create the argument list. */
3289 vec_safe_insert (*placement, 0, size);
3290 /* Do name-lookup to find the appropriate operator. */
3291 fns = lookup_fnfields (elt_type, fnname, /*protect=*/2);
3292 if (fns == NULL_TREE)
3293 {
3294 if (complain & tf_error)
3295 error ("no suitable %qD found in class %qT", fnname, elt_type);
3296 return error_mark_node;
3297 }
3298 if (TREE_CODE (fns) == TREE_LIST)
3299 {
3300 if (complain & tf_error)
3301 {
3302 error ("request for member %qD is ambiguous", fnname);
3303 print_candidates (fns);
3304 }
3305 return error_mark_node;
3306 }
3307 tree dummy = build_dummy_object (elt_type);
3308 alloc_call = NULL_TREE;
3309 if (align_arg)
3310 {
3311 vec<tree, va_gc> *align_args
3312 = vec_copy_and_insert (*placement, align_arg, 1);
3313 alloc_call
3314 = build_new_method_call (dummy, fns, &align_args,
3315 /*conversion_path=*/NULL_TREE,
3316 LOOKUP_NORMAL, &alloc_fn, tf_none);
3317 /* If no matching function is found and the allocated object type
3318 has new-extended alignment, the alignment argument is removed
3319 from the argument list, and overload resolution is performed
3320 again. */
3321 if (alloc_call == error_mark_node)
3322 alloc_call = NULL_TREE;
3323 }
3324 if (!alloc_call)
3325 alloc_call = build_new_method_call (dummy, fns, placement,
3326 /*conversion_path=*/NULL_TREE,
3327 LOOKUP_NORMAL,
3328 &alloc_fn, complain);
3329 }
3330 else
3331 {
3332 /* Use a global operator new. */
3333 /* See if a cookie might be required. */
3334 if (!(array_p && TYPE_VEC_NEW_USES_COOKIE (elt_type)))
3335 {
3336 cookie_size = NULL_TREE;
3337 /* No size arithmetic necessary, so the size check is
3338 not needed. */
3339 if (outer_nelts_check != NULL && inner_size == 1)
3340 outer_nelts_check = NULL_TREE;
3341 }
3342
3343 alloc_call = build_operator_new_call (fnname, placement,
3344 &size, &cookie_size,
3345 align_arg, outer_nelts_check,
3346 &alloc_fn, complain);
3347 }
3348
3349 if (alloc_call == error_mark_node)
3350 return error_mark_node;
3351
3352 gcc_assert (alloc_fn != NULL_TREE);
3353
3354 /* Now, check to see if this function is actually a placement
3355 allocation function. This can happen even when PLACEMENT is NULL
3356 because we might have something like:
3357
3358 struct S { void* operator new (size_t, int i = 0); };
3359
3360 A call to `new S' will get this allocation function, even though
3361 there is no explicit placement argument. If there is more than
3362 one argument, or there are variable arguments, then this is a
3363 placement allocation function. */
3364 placement_allocation_fn_p
3365 = (type_num_arguments (TREE_TYPE (alloc_fn)) > 1
3366 || varargs_function_p (alloc_fn));
3367
3368 if (warn_aligned_new
3369 && !placement_allocation_fn_p
3370 && TYPE_ALIGN (elt_type) > malloc_alignment ()
3371 && (warn_aligned_new > 1
3372 || CP_DECL_CONTEXT (alloc_fn) == global_namespace)
3373 && !aligned_allocation_fn_p (alloc_fn))
3374 {
3375 auto_diagnostic_group d;
3376 if (warning (OPT_Waligned_new_, "%<new%> of type %qT with extended "
3377 "alignment %d", elt_type, TYPE_ALIGN_UNIT (elt_type)))
3378 {
3379 inform (input_location, "uses %qD, which does not have an alignment "
3380 "parameter", alloc_fn);
3381 if (!aligned_new_threshold)
3382 inform (input_location, "use %<-faligned-new%> to enable C++17 "
3383 "over-aligned new support");
3384 }
3385 }
3386
3387 /* If we found a simple case of PLACEMENT_EXPR above, then copy it
3388 into a temporary variable. */
3389 if (!processing_template_decl
3390 && TREE_CODE (alloc_call) == CALL_EXPR
3391 && call_expr_nargs (alloc_call) == 2
3392 && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (alloc_call, 0))) == INTEGER_TYPE
3393 && TYPE_PTR_P (TREE_TYPE (CALL_EXPR_ARG (alloc_call, 1))))
3394 {
3395 tree placement = CALL_EXPR_ARG (alloc_call, 1);
3396
3397 if (placement_first != NULL_TREE
3398 && (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (TREE_TYPE (placement)))
3399 || VOID_TYPE_P (TREE_TYPE (TREE_TYPE (placement)))))
3400 {
3401 placement_expr = get_target_expr (placement_first);
3402 CALL_EXPR_ARG (alloc_call, 1)
3403 = fold_convert (TREE_TYPE (placement), placement_expr);
3404 }
3405
3406 if (!member_new_p
3407 && VOID_TYPE_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_ARG (alloc_call, 1)))))
3408 {
3409 /* Attempt to make the warning point at the operator new argument. */
3410 if (placement_first)
3411 placement = placement_first;
3412
3413 warn_placement_new_too_small (orig_type, nelts, size, placement);
3414 }
3415 }
3416
3417 tree alloc_call_expr = extract_call_expr (alloc_call);
3418 if (TREE_CODE (alloc_call_expr) == CALL_EXPR)
3419 CALL_FROM_NEW_OR_DELETE_P (alloc_call_expr) = 1;
3420
3421 if (cookie_size)
3422 alloc_call = maybe_wrap_new_for_constexpr (alloc_call, elt_type,
3423 cookie_size);
3424
3425 /* In the simple case, we can stop now. */
3426 pointer_type = build_pointer_type (type);
3427 if (!cookie_size && !is_initialized)
3428 return build_nop (pointer_type, alloc_call);
3429
3430 /* Store the result of the allocation call in a variable so that we can
3431 use it more than once. */
3432 alloc_expr = get_target_expr (alloc_call);
3433 alloc_node = TARGET_EXPR_SLOT (alloc_expr);
3434
3435 /* Strip any COMPOUND_EXPRs from ALLOC_CALL. */
3436 while (TREE_CODE (alloc_call) == COMPOUND_EXPR)
3437 alloc_call = TREE_OPERAND (alloc_call, 1);
3438
3439 /* Preevaluate the placement args so that we don't reevaluate them for a
3440 placement delete. */
3441 if (placement_allocation_fn_p)
3442 {
3443 tree inits;
3444 stabilize_call (alloc_call, &inits);
3445 if (inits)
3446 alloc_expr = build2 (COMPOUND_EXPR, TREE_TYPE (alloc_expr), inits,
3447 alloc_expr);
3448 }
3449
3450 /* unless an allocation function is declared with an empty excep-
3451 tion-specification (_except.spec_), throw(), it indicates failure to
3452 allocate storage by throwing a bad_alloc exception (clause _except_,
3453 _lib.bad.alloc_); it returns a non-null pointer otherwise If the allo-
3454 cation function is declared with an empty exception-specification,
3455 throw(), it returns null to indicate failure to allocate storage and a
3456 non-null pointer otherwise.
3457
3458 So check for a null exception spec on the op new we just called. */
3459
3460 nothrow = TYPE_NOTHROW_P (TREE_TYPE (alloc_fn));
3461 check_new
3462 = flag_check_new || (nothrow && !std_placement_new_fn_p (alloc_fn));
3463
3464 if (cookie_size)
3465 {
3466 tree cookie;
3467 tree cookie_ptr;
3468 tree size_ptr_type;
3469
3470 /* Adjust so we're pointing to the start of the object. */
3471 data_addr = fold_build_pointer_plus (alloc_node, cookie_size);
3472
3473 /* Store the number of bytes allocated so that we can know how
3474 many elements to destroy later. We use the last sizeof
3475 (size_t) bytes to store the number of elements. */
3476 cookie_ptr = size_binop (MINUS_EXPR, cookie_size, size_in_bytes (sizetype));
3477 cookie_ptr = fold_build_pointer_plus_loc (input_location,
3478 alloc_node, cookie_ptr);
3479 size_ptr_type = build_pointer_type (sizetype);
3480 cookie_ptr = fold_convert (size_ptr_type, cookie_ptr);
3481 cookie = cp_build_fold_indirect_ref (cookie_ptr);
3482
3483 cookie_expr = build2 (MODIFY_EXPR, sizetype, cookie, nelts);
3484
3485 if (targetm.cxx.cookie_has_size ())
3486 {
3487 /* Also store the element size. */
3488 cookie_ptr = fold_build_pointer_plus (cookie_ptr,
3489 fold_build1_loc (input_location,
3490 NEGATE_EXPR, sizetype,
3491 size_in_bytes (sizetype)));
3492
3493 cookie = cp_build_fold_indirect_ref (cookie_ptr);
3494 cookie = build2 (MODIFY_EXPR, sizetype, cookie,
3495 size_in_bytes (elt_type));
3496 cookie_expr = build2 (COMPOUND_EXPR, TREE_TYPE (cookie_expr),
3497 cookie, cookie_expr);
3498 }
3499 }
3500 else
3501 {
3502 cookie_expr = NULL_TREE;
3503 data_addr = alloc_node;
3504 }
3505
3506 /* Now use a pointer to the type we've actually allocated. */
3507
3508 /* But we want to operate on a non-const version to start with,
3509 since we'll be modifying the elements. */
3510 non_const_pointer_type = build_pointer_type
3511 (cp_build_qualified_type (type, cp_type_quals (type) & ~TYPE_QUAL_CONST));
3512
3513 data_addr = fold_convert (non_const_pointer_type, data_addr);
3514 /* Any further uses of alloc_node will want this type, too. */
3515 alloc_node = fold_convert (non_const_pointer_type, alloc_node);
3516
3517 /* Now initialize the allocated object. Note that we preevaluate the
3518 initialization expression, apart from the actual constructor call or
3519 assignment--we do this because we want to delay the allocation as long
3520 as possible in order to minimize the size of the exception region for
3521 placement delete. */
3522 if (is_initialized)
3523 {
3524 bool stable;
3525 bool explicit_value_init_p = false;
3526
3527 if (*init != NULL && (*init)->is_empty ())
3528 {
3529 *init = NULL;
3530 explicit_value_init_p = true;
3531 }
3532
3533 if (processing_template_decl)
3534 {
3535 /* Avoid an ICE when converting to a base in build_simple_base_path.
3536 We'll throw this all away anyway, and build_new will create
3537 a NEW_EXPR. */
3538 tree t = fold_convert (build_pointer_type (elt_type), data_addr);
3539 /* build_value_init doesn't work in templates, and we don't need
3540 the initializer anyway since we're going to throw it away and
3541 rebuild it at instantiation time, so just build up a single
3542 constructor call to get any appropriate diagnostics. */
3543 init_expr = cp_build_fold_indirect_ref (t);
3544 if (type_build_ctor_call (elt_type))
3545 init_expr = build_special_member_call (init_expr,
3546 complete_ctor_identifier,
3547 init, elt_type,
3548 LOOKUP_NORMAL,
3549 complain);
3550 stable = stabilize_init (init_expr, &init_preeval_expr);
3551 }
3552 else if (array_p)
3553 {
3554 tree vecinit = NULL_TREE;
3555 if (vec_safe_length (*init) == 1
3556 && DIRECT_LIST_INIT_P ((**init)[0]))
3557 {
3558 vecinit = (**init)[0];
3559 if (CONSTRUCTOR_NELTS (vecinit) == 0)
3560 /* List-value-initialization, leave it alone. */;
3561 else
3562 {
3563 tree arraytype, domain;
3564 if (TREE_CONSTANT (nelts))
3565 domain = compute_array_index_type (NULL_TREE, nelts,
3566 complain);
3567 else
3568 /* We'll check the length at runtime. */
3569 domain = NULL_TREE;
3570 arraytype = build_cplus_array_type (type, domain);
3571 vecinit = digest_init (arraytype, vecinit, complain);
3572 }
3573 }
3574 else if (*init)
3575 {
3576 if (complain & tf_error)
3577 error ("parenthesized initializer in array new");
3578 return error_mark_node;
3579 }
3580 init_expr
3581 = build_vec_init (data_addr,
3582 cp_build_binary_op (input_location,
3583 MINUS_EXPR, outer_nelts,
3584 integer_one_node,
3585 complain),
3586 vecinit,
3587 explicit_value_init_p,
3588 /*from_array=*/0,
3589 complain);
3590
3591 /* An array initialization is stable because the initialization
3592 of each element is a full-expression, so the temporaries don't
3593 leak out. */
3594 stable = true;
3595 }
3596 else
3597 {
3598 init_expr = cp_build_fold_indirect_ref (data_addr);
3599
3600 if (type_build_ctor_call (type) && !explicit_value_init_p)
3601 {
3602 init_expr = build_special_member_call (init_expr,
3603 complete_ctor_identifier,
3604 init, elt_type,
3605 LOOKUP_NORMAL,
3606 complain|tf_no_cleanup);
3607 }
3608 else if (explicit_value_init_p)
3609 {
3610 /* Something like `new int()'. NO_CLEANUP is needed so
3611 we don't try and build a (possibly ill-formed)
3612 destructor. */
3613 tree val = build_value_init (type, complain | tf_no_cleanup);
3614 if (val == error_mark_node)
3615 return error_mark_node;
3616 init_expr = build2 (INIT_EXPR, type, init_expr, val);
3617 }
3618 else
3619 {
3620 tree ie;
3621
3622 /* We are processing something like `new int (10)', which
3623 means allocate an int, and initialize it with 10.
3624
3625 In C++20, also handle `new A(1, 2)'. */
3626 if (cxx_dialect >= cxx2a
3627 && AGGREGATE_TYPE_P (type)
3628 && (*init)->length () > 1)
3629 {
3630 ie = build_tree_list_vec (*init);
3631 ie = build_constructor_from_list (init_list_type_node, ie);
3632 CONSTRUCTOR_IS_DIRECT_INIT (ie) = true;
3633 CONSTRUCTOR_IS_PAREN_INIT (ie) = true;
3634 ie = digest_init (type, ie, complain);
3635 }
3636 else
3637 ie = build_x_compound_expr_from_vec (*init, "new initializer",
3638 complain);
3639 init_expr = cp_build_modify_expr (input_location, init_expr,
3640 INIT_EXPR, ie, complain);
3641 }
3642 /* If the initializer uses C++14 aggregate NSDMI that refer to the
3643 object being initialized, replace them now and don't try to
3644 preevaluate. */
3645 bool had_placeholder = false;
3646 if (!processing_template_decl
3647 && TREE_CODE (init_expr) == INIT_EXPR)
3648 TREE_OPERAND (init_expr, 1)
3649 = replace_placeholders (TREE_OPERAND (init_expr, 1),
3650 TREE_OPERAND (init_expr, 0),
3651 &had_placeholder);
3652 stable = (!had_placeholder
3653 && stabilize_init (init_expr, &init_preeval_expr));
3654 }
3655
3656 if (init_expr == error_mark_node)
3657 return error_mark_node;
3658
3659 /* If any part of the object initialization terminates by throwing an
3660 exception and a suitable deallocation function can be found, the
3661 deallocation function is called to free the memory in which the
3662 object was being constructed, after which the exception continues
3663 to propagate in the context of the new-expression. If no
3664 unambiguous matching deallocation function can be found,
3665 propagating the exception does not cause the object's memory to be
3666 freed. */
3667 if (flag_exceptions)
3668 {
3669 enum tree_code dcode = array_p ? VEC_DELETE_EXPR : DELETE_EXPR;
3670 tree cleanup;
3671
3672 /* The Standard is unclear here, but the right thing to do
3673 is to use the same method for finding deallocation
3674 functions that we use for finding allocation functions. */
3675 cleanup = (build_op_delete_call
3676 (dcode,
3677 alloc_node,
3678 size,
3679 globally_qualified_p,
3680 placement_allocation_fn_p ? alloc_call : NULL_TREE,
3681 alloc_fn,
3682 complain));
3683
3684 if (!cleanup)
3685 /* We're done. */;
3686 else if (stable)
3687 /* This is much simpler if we were able to preevaluate all of
3688 the arguments to the constructor call. */
3689 {
3690 /* CLEANUP is compiler-generated, so no diagnostics. */
3691 TREE_NO_WARNING (cleanup) = true;
3692 init_expr = build2 (TRY_CATCH_EXPR, void_type_node,
3693 init_expr, cleanup);
3694 /* Likewise, this try-catch is compiler-generated. */
3695 TREE_NO_WARNING (init_expr) = true;
3696 }
3697 else
3698 /* Ack! First we allocate the memory. Then we set our sentry
3699 variable to true, and expand a cleanup that deletes the
3700 memory if sentry is true. Then we run the constructor, and
3701 finally clear the sentry.
3702
3703 We need to do this because we allocate the space first, so
3704 if there are any temporaries with cleanups in the
3705 constructor args and we weren't able to preevaluate them, we
3706 need this EH region to extend until end of full-expression
3707 to preserve nesting. */
3708 {
3709 tree end, sentry, begin;
3710
3711 begin = get_target_expr (boolean_true_node);
3712 CLEANUP_EH_ONLY (begin) = 1;
3713
3714 sentry = TARGET_EXPR_SLOT (begin);
3715
3716 /* CLEANUP is compiler-generated, so no diagnostics. */
3717 TREE_NO_WARNING (cleanup) = true;
3718
3719 TARGET_EXPR_CLEANUP (begin)
3720 = build3 (COND_EXPR, void_type_node, sentry,
3721 cleanup, void_node);
3722
3723 end = build2 (MODIFY_EXPR, TREE_TYPE (sentry),
3724 sentry, boolean_false_node);
3725
3726 init_expr
3727 = build2 (COMPOUND_EXPR, void_type_node, begin,
3728 build2 (COMPOUND_EXPR, void_type_node, init_expr,
3729 end));
3730 /* Likewise, this is compiler-generated. */
3731 TREE_NO_WARNING (init_expr) = true;
3732 }
3733 }
3734 }
3735 else
3736 init_expr = NULL_TREE;
3737
3738 /* Now build up the return value in reverse order. */
3739
3740 rval = data_addr;
3741
3742 if (init_expr)
3743 rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), init_expr, rval);
3744 if (cookie_expr)
3745 rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), cookie_expr, rval);
3746
3747 if (rval == data_addr)
3748 /* If we don't have an initializer or a cookie, strip the TARGET_EXPR
3749 and return the call (which doesn't need to be adjusted). */
3750 rval = TARGET_EXPR_INITIAL (alloc_expr);
3751 else
3752 {
3753 if (check_new)
3754 {
3755 tree ifexp = cp_build_binary_op (input_location,
3756 NE_EXPR, alloc_node,
3757 nullptr_node,
3758 complain);
3759 rval = build_conditional_expr (input_location, ifexp, rval,
3760 alloc_node, complain);
3761 }
3762
3763 /* Perform the allocation before anything else, so that ALLOC_NODE
3764 has been initialized before we start using it. */
3765 rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), alloc_expr, rval);
3766 }
3767
3768 if (init_preeval_expr)
3769 rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), init_preeval_expr, rval);
3770
3771 /* A new-expression is never an lvalue. */
3772 gcc_assert (!obvalue_p (rval));
3773
3774 return convert (pointer_type, rval);
3775 }
3776
3777 /* Generate a representation for a C++ "new" expression. *PLACEMENT
3778 is a vector of placement-new arguments (or NULL if none). If NELTS
3779 is NULL, TYPE is the type of the storage to be allocated. If NELTS
3780 is not NULL, then this is an array-new allocation; TYPE is the type
3781 of the elements in the array and NELTS is the number of elements in
3782 the array. *INIT, if non-NULL, is the initializer for the new
3783 object, or an empty vector to indicate an initializer of "()". If
3784 USE_GLOBAL_NEW is true, then the user explicitly wrote "::new"
3785 rather than just "new". This may change PLACEMENT and INIT. */
3786
3787 tree
build_new(location_t loc,vec<tree,va_gc> ** placement,tree type,tree nelts,vec<tree,va_gc> ** init,int use_global_new,tsubst_flags_t complain)3788 build_new (location_t loc, vec<tree, va_gc> **placement, tree type,
3789 tree nelts, vec<tree, va_gc> **init, int use_global_new,
3790 tsubst_flags_t complain)
3791 {
3792 tree rval;
3793 vec<tree, va_gc> *orig_placement = NULL;
3794 tree orig_nelts = NULL_TREE;
3795 vec<tree, va_gc> *orig_init = NULL;
3796
3797 if (type == error_mark_node)
3798 return error_mark_node;
3799
3800 if (nelts == NULL_TREE
3801 /* Don't do auto deduction where it might affect mangling. */
3802 && (!processing_template_decl || at_function_scope_p ()))
3803 {
3804 tree auto_node = type_uses_auto (type);
3805 if (auto_node)
3806 {
3807 tree d_init = NULL_TREE;
3808 const size_t len = vec_safe_length (*init);
3809 /* E.g. new auto(x) must have exactly one element, or
3810 a {} initializer will have one element. */
3811 if (len == 1)
3812 {
3813 d_init = (**init)[0];
3814 d_init = resolve_nondeduced_context (d_init, complain);
3815 }
3816 /* For the rest, e.g. new A(1, 2, 3), create a list. */
3817 else if (len > 1)
3818 {
3819 unsigned int n;
3820 tree t;
3821 tree *pp = &d_init;
3822 FOR_EACH_VEC_ELT (**init, n, t)
3823 {
3824 t = resolve_nondeduced_context (t, complain);
3825 *pp = build_tree_list (NULL_TREE, t);
3826 pp = &TREE_CHAIN (*pp);
3827 }
3828 }
3829 type = do_auto_deduction (type, d_init, auto_node, complain);
3830 }
3831 }
3832
3833 if (processing_template_decl)
3834 {
3835 if (dependent_type_p (type)
3836 || any_type_dependent_arguments_p (*placement)
3837 || (nelts && type_dependent_expression_p (nelts))
3838 || (nelts && *init)
3839 || any_type_dependent_arguments_p (*init))
3840 return build_raw_new_expr (loc, *placement, type, nelts, *init,
3841 use_global_new);
3842
3843 orig_placement = make_tree_vector_copy (*placement);
3844 orig_nelts = nelts;
3845 if (*init)
3846 {
3847 orig_init = make_tree_vector_copy (*init);
3848 /* Also copy any CONSTRUCTORs in *init, since reshape_init and
3849 digest_init clobber them in place. */
3850 for (unsigned i = 0; i < orig_init->length(); ++i)
3851 {
3852 tree e = (**init)[i];
3853 if (TREE_CODE (e) == CONSTRUCTOR)
3854 (**init)[i] = copy_node (e);
3855 }
3856 }
3857
3858 make_args_non_dependent (*placement);
3859 if (nelts)
3860 nelts = build_non_dependent_expr (nelts);
3861 make_args_non_dependent (*init);
3862 }
3863
3864 if (nelts)
3865 {
3866 location_t nelts_loc = cp_expr_loc_or_loc (nelts, loc);
3867 if (!build_expr_type_conversion (WANT_INT | WANT_ENUM, nelts, false))
3868 {
3869 if (complain & tf_error)
3870 permerror (nelts_loc,
3871 "size in array new must have integral type");
3872 else
3873 return error_mark_node;
3874 }
3875
3876 /* Try to determine the constant value only for the purposes
3877 of the diagnostic below but continue to use the original
3878 value and handle const folding later. */
3879 const_tree cst_nelts = fold_non_dependent_expr (nelts, complain);
3880
3881 /* The expression in a noptr-new-declarator is erroneous if it's of
3882 non-class type and its value before converting to std::size_t is
3883 less than zero. ... If the expression is a constant expression,
3884 the program is ill-fomed. */
3885 if (TREE_CODE (cst_nelts) == INTEGER_CST
3886 && !valid_array_size_p (nelts_loc, cst_nelts, NULL_TREE,
3887 complain & tf_error))
3888 return error_mark_node;
3889
3890 nelts = mark_rvalue_use (nelts);
3891 nelts = cp_save_expr (cp_convert (sizetype, nelts, complain));
3892 }
3893
3894 /* ``A reference cannot be created by the new operator. A reference
3895 is not an object (8.2.2, 8.4.3), so a pointer to it could not be
3896 returned by new.'' ARM 5.3.3 */
3897 if (TYPE_REF_P (type))
3898 {
3899 if (complain & tf_error)
3900 error_at (loc, "new cannot be applied to a reference type");
3901 else
3902 return error_mark_node;
3903 type = TREE_TYPE (type);
3904 }
3905
3906 if (TREE_CODE (type) == FUNCTION_TYPE)
3907 {
3908 if (complain & tf_error)
3909 error_at (loc, "new cannot be applied to a function type");
3910 return error_mark_node;
3911 }
3912
3913 /* The type allocated must be complete. If the new-type-id was
3914 "T[N]" then we are just checking that "T" is complete here, but
3915 that is equivalent, since the value of "N" doesn't matter. */
3916 if (!complete_type_or_maybe_complain (type, NULL_TREE, complain))
3917 return error_mark_node;
3918
3919 rval = build_new_1 (placement, type, nelts, init, use_global_new, complain);
3920 if (rval == error_mark_node)
3921 return error_mark_node;
3922
3923 if (processing_template_decl)
3924 {
3925 tree ret = build_raw_new_expr (loc, orig_placement, type, orig_nelts,
3926 orig_init, use_global_new);
3927 release_tree_vector (orig_placement);
3928 release_tree_vector (orig_init);
3929 return ret;
3930 }
3931
3932 /* Wrap it in a NOP_EXPR so warn_if_unused_value doesn't complain. */
3933 rval = build1_loc (loc, NOP_EXPR, TREE_TYPE (rval), rval);
3934 TREE_NO_WARNING (rval) = 1;
3935
3936 return rval;
3937 }
3938
3939 static tree
build_vec_delete_1(location_t loc,tree base,tree maxindex,tree type,special_function_kind auto_delete_vec,int use_global_delete,tsubst_flags_t complain)3940 build_vec_delete_1 (location_t loc, tree base, tree maxindex, tree type,
3941 special_function_kind auto_delete_vec,
3942 int use_global_delete, tsubst_flags_t complain)
3943 {
3944 tree virtual_size;
3945 tree ptype = build_pointer_type (type = complete_type (type));
3946 tree size_exp;
3947
3948 /* Temporary variables used by the loop. */
3949 tree tbase, tbase_init;
3950
3951 /* This is the body of the loop that implements the deletion of a
3952 single element, and moves temp variables to next elements. */
3953 tree body;
3954
3955 /* This is the LOOP_EXPR that governs the deletion of the elements. */
3956 tree loop = 0;
3957
3958 /* This is the thing that governs what to do after the loop has run. */
3959 tree deallocate_expr = 0;
3960
3961 /* This is the BIND_EXPR which holds the outermost iterator of the
3962 loop. It is convenient to set this variable up and test it before
3963 executing any other code in the loop.
3964 This is also the containing expression returned by this function. */
3965 tree controller = NULL_TREE;
3966 tree tmp;
3967
3968 /* We should only have 1-D arrays here. */
3969 gcc_assert (TREE_CODE (type) != ARRAY_TYPE);
3970
3971 if (base == error_mark_node || maxindex == error_mark_node)
3972 return error_mark_node;
3973
3974 if (!verify_type_context (loc, TCTX_DEALLOCATION, type,
3975 !(complain & tf_error)))
3976 return error_mark_node;
3977
3978 if (!COMPLETE_TYPE_P (type))
3979 {
3980 if (complain & tf_warning)
3981 {
3982 auto_diagnostic_group d;
3983 if (warning_at (loc, OPT_Wdelete_incomplete,
3984 "possible problem detected in invocation of "
3985 "operator %<delete []%>"))
3986 {
3987 cxx_incomplete_type_diagnostic (base, type, DK_WARNING);
3988 inform (loc, "neither the destructor nor the "
3989 "class-specific operator %<delete []%> will be called, "
3990 "even if they are declared when the class is defined");
3991 }
3992 }
3993 /* This size won't actually be used. */
3994 size_exp = size_one_node;
3995 goto no_destructor;
3996 }
3997
3998 size_exp = size_in_bytes (type);
3999
4000 if (! MAYBE_CLASS_TYPE_P (type))
4001 goto no_destructor;
4002 else if (TYPE_HAS_TRIVIAL_DESTRUCTOR (type))
4003 {
4004 /* Make sure the destructor is callable. */
4005 if (type_build_dtor_call (type))
4006 {
4007 tmp = build_delete (loc, ptype, base, sfk_complete_destructor,
4008 LOOKUP_NORMAL|LOOKUP_DESTRUCTOR, 1,
4009 complain);
4010 if (tmp == error_mark_node)
4011 return error_mark_node;
4012 }
4013 goto no_destructor;
4014 }
4015
4016 /* The below is short by the cookie size. */
4017 virtual_size = size_binop (MULT_EXPR, size_exp,
4018 fold_convert (sizetype, maxindex));
4019
4020 tbase = create_temporary_var (ptype);
4021 DECL_INITIAL (tbase)
4022 = fold_build_pointer_plus_loc (loc, fold_convert (ptype, base),
4023 virtual_size);
4024 tbase_init = build_stmt (loc, DECL_EXPR, tbase);
4025 controller = build3 (BIND_EXPR, void_type_node, tbase, NULL_TREE, NULL_TREE);
4026 TREE_SIDE_EFFECTS (controller) = 1;
4027
4028 body = build1 (EXIT_EXPR, void_type_node,
4029 build2 (EQ_EXPR, boolean_type_node, tbase,
4030 fold_convert (ptype, base)));
4031 tmp = fold_build1_loc (loc, NEGATE_EXPR, sizetype, size_exp);
4032 tmp = fold_build_pointer_plus (tbase, tmp);
4033 tmp = cp_build_modify_expr (loc, tbase, NOP_EXPR, tmp, complain);
4034 if (tmp == error_mark_node)
4035 return error_mark_node;
4036 body = build_compound_expr (loc, body, tmp);
4037 tmp = build_delete (loc, ptype, tbase, sfk_complete_destructor,
4038 LOOKUP_NORMAL|LOOKUP_DESTRUCTOR, 1,
4039 complain);
4040 if (tmp == error_mark_node)
4041 return error_mark_node;
4042 body = build_compound_expr (loc, body, tmp);
4043
4044 loop = build1 (LOOP_EXPR, void_type_node, body);
4045 loop = build_compound_expr (loc, tbase_init, loop);
4046
4047 no_destructor:
4048 /* Delete the storage if appropriate. */
4049 if (auto_delete_vec == sfk_deleting_destructor)
4050 {
4051 tree base_tbd;
4052
4053 /* The below is short by the cookie size. */
4054 virtual_size = size_binop (MULT_EXPR, size_exp,
4055 fold_convert (sizetype, maxindex));
4056
4057 if (! TYPE_VEC_NEW_USES_COOKIE (type))
4058 /* no header */
4059 base_tbd = base;
4060 else
4061 {
4062 tree cookie_size;
4063
4064 cookie_size = targetm.cxx.get_cookie_size (type);
4065 base_tbd = cp_build_binary_op (loc,
4066 MINUS_EXPR,
4067 cp_convert (string_type_node,
4068 base, complain),
4069 cookie_size,
4070 complain);
4071 if (base_tbd == error_mark_node)
4072 return error_mark_node;
4073 base_tbd = cp_convert (ptype, base_tbd, complain);
4074 /* True size with header. */
4075 virtual_size = size_binop (PLUS_EXPR, virtual_size, cookie_size);
4076 }
4077
4078 deallocate_expr = build_op_delete_call (VEC_DELETE_EXPR,
4079 base_tbd, virtual_size,
4080 use_global_delete & 1,
4081 /*placement=*/NULL_TREE,
4082 /*alloc_fn=*/NULL_TREE,
4083 complain);
4084
4085 tree deallocate_call_expr = extract_call_expr (deallocate_expr);
4086 if (TREE_CODE (deallocate_call_expr) == CALL_EXPR)
4087 CALL_FROM_NEW_OR_DELETE_P (deallocate_call_expr) = 1;
4088 }
4089
4090 body = loop;
4091 if (!deallocate_expr)
4092 ;
4093 else if (!body)
4094 body = deallocate_expr;
4095 else
4096 /* The delete operator must be called, even if a destructor
4097 throws. */
4098 body = build2 (TRY_FINALLY_EXPR, void_type_node, body, deallocate_expr);
4099
4100 if (!body)
4101 body = integer_zero_node;
4102
4103 /* Outermost wrapper: If pointer is null, punt. */
4104 tree cond = build2_loc (loc, NE_EXPR, boolean_type_node, base,
4105 fold_convert (TREE_TYPE (base), nullptr_node));
4106 /* This is a compiler generated comparison, don't emit
4107 e.g. -Wnonnull-compare warning for it. */
4108 TREE_NO_WARNING (cond) = 1;
4109 body = build3_loc (loc, COND_EXPR, void_type_node,
4110 cond, body, integer_zero_node);
4111 COND_EXPR_IS_VEC_DELETE (body) = true;
4112 body = build1 (NOP_EXPR, void_type_node, body);
4113
4114 if (controller)
4115 {
4116 TREE_OPERAND (controller, 1) = body;
4117 body = controller;
4118 }
4119
4120 if (TREE_CODE (base) == SAVE_EXPR)
4121 /* Pre-evaluate the SAVE_EXPR outside of the BIND_EXPR. */
4122 body = build2 (COMPOUND_EXPR, void_type_node, base, body);
4123
4124 return convert_to_void (body, ICV_CAST, complain);
4125 }
4126
4127 /* Create an unnamed variable of the indicated TYPE. */
4128
4129 tree
create_temporary_var(tree type)4130 create_temporary_var (tree type)
4131 {
4132 tree decl;
4133
4134 decl = build_decl (input_location,
4135 VAR_DECL, NULL_TREE, type);
4136 TREE_USED (decl) = 1;
4137 DECL_ARTIFICIAL (decl) = 1;
4138 DECL_IGNORED_P (decl) = 1;
4139 DECL_CONTEXT (decl) = current_function_decl;
4140
4141 return decl;
4142 }
4143
4144 /* Create a new temporary variable of the indicated TYPE, initialized
4145 to INIT.
4146
4147 It is not entered into current_binding_level, because that breaks
4148 things when it comes time to do final cleanups (which take place
4149 "outside" the binding contour of the function). */
4150
4151 tree
get_temp_regvar(tree type,tree init)4152 get_temp_regvar (tree type, tree init)
4153 {
4154 tree decl;
4155
4156 decl = create_temporary_var (type);
4157 add_decl_expr (decl);
4158
4159 finish_expr_stmt (cp_build_modify_expr (input_location, decl, INIT_EXPR,
4160 init, tf_warning_or_error));
4161
4162 return decl;
4163 }
4164
4165 /* Subroutine of build_vec_init. Returns true if assigning to an array of
4166 INNER_ELT_TYPE from INIT is trivial. */
4167
4168 static bool
vec_copy_assign_is_trivial(tree inner_elt_type,tree init)4169 vec_copy_assign_is_trivial (tree inner_elt_type, tree init)
4170 {
4171 tree fromtype = inner_elt_type;
4172 if (lvalue_p (init))
4173 fromtype = cp_build_reference_type (fromtype, /*rval*/false);
4174 return is_trivially_xible (MODIFY_EXPR, inner_elt_type, fromtype);
4175 }
4176
4177 /* Subroutine of build_vec_init: Check that the array has at least N
4178 elements. Other parameters are local variables in build_vec_init. */
4179
4180 void
finish_length_check(tree atype,tree iterator,tree obase,unsigned n)4181 finish_length_check (tree atype, tree iterator, tree obase, unsigned n)
4182 {
4183 tree nelts = build_int_cst (ptrdiff_type_node, n - 1);
4184 if (TREE_CODE (atype) != ARRAY_TYPE)
4185 {
4186 if (flag_exceptions)
4187 {
4188 tree c = fold_build2 (LT_EXPR, boolean_type_node, iterator,
4189 nelts);
4190 c = build3 (COND_EXPR, void_type_node, c,
4191 throw_bad_array_new_length (), void_node);
4192 finish_expr_stmt (c);
4193 }
4194 /* Don't check an array new when -fno-exceptions. */
4195 }
4196 else if (sanitize_flags_p (SANITIZE_BOUNDS)
4197 && current_function_decl != NULL_TREE)
4198 {
4199 /* Make sure the last element of the initializer is in bounds. */
4200 finish_expr_stmt
4201 (ubsan_instrument_bounds
4202 (input_location, obase, &nelts, /*ignore_off_by_one*/false));
4203 }
4204 }
4205
4206 /* `build_vec_init' returns tree structure that performs
4207 initialization of a vector of aggregate types.
4208
4209 BASE is a reference to the vector, of ARRAY_TYPE, or a pointer
4210 to the first element, of POINTER_TYPE.
4211 MAXINDEX is the maximum index of the array (one less than the
4212 number of elements). It is only used if BASE is a pointer or
4213 TYPE_DOMAIN (TREE_TYPE (BASE)) == NULL_TREE.
4214
4215 INIT is the (possibly NULL) initializer.
4216
4217 If EXPLICIT_VALUE_INIT_P is true, then INIT must be NULL. All
4218 elements in the array are value-initialized.
4219
4220 FROM_ARRAY is 0 if we should init everything with INIT
4221 (i.e., every element initialized from INIT).
4222 FROM_ARRAY is 1 if we should index into INIT in parallel
4223 with initialization of DECL.
4224 FROM_ARRAY is 2 if we should index into INIT in parallel,
4225 but use assignment instead of initialization. */
4226
4227 tree
build_vec_init(tree base,tree maxindex,tree init,bool explicit_value_init_p,int from_array,tsubst_flags_t complain)4228 build_vec_init (tree base, tree maxindex, tree init,
4229 bool explicit_value_init_p,
4230 int from_array, tsubst_flags_t complain)
4231 {
4232 tree rval;
4233 tree base2 = NULL_TREE;
4234 tree itype = NULL_TREE;
4235 tree iterator;
4236 /* The type of BASE. */
4237 tree atype = TREE_TYPE (base);
4238 /* The type of an element in the array. */
4239 tree type = TREE_TYPE (atype);
4240 /* The element type reached after removing all outer array
4241 types. */
4242 tree inner_elt_type;
4243 /* The type of a pointer to an element in the array. */
4244 tree ptype;
4245 tree stmt_expr;
4246 tree compound_stmt;
4247 int destroy_temps;
4248 tree try_block = NULL_TREE;
4249 HOST_WIDE_INT num_initialized_elts = 0;
4250 bool is_global;
4251 tree obase = base;
4252 bool xvalue = false;
4253 bool errors = false;
4254 location_t loc = (init ? cp_expr_loc_or_input_loc (init)
4255 : location_of (base));
4256
4257 if (TREE_CODE (atype) == ARRAY_TYPE && TYPE_DOMAIN (atype))
4258 maxindex = array_type_nelts (atype);
4259
4260 if (maxindex == NULL_TREE || maxindex == error_mark_node)
4261 return error_mark_node;
4262
4263 maxindex = maybe_constant_value (maxindex);
4264 if (explicit_value_init_p)
4265 gcc_assert (!init);
4266
4267 inner_elt_type = strip_array_types (type);
4268
4269 /* Look through the TARGET_EXPR around a compound literal. */
4270 if (init && TREE_CODE (init) == TARGET_EXPR
4271 && TREE_CODE (TARGET_EXPR_INITIAL (init)) == CONSTRUCTOR
4272 && from_array != 2)
4273 init = TARGET_EXPR_INITIAL (init);
4274
4275 bool direct_init = false;
4276 if (from_array && init && BRACE_ENCLOSED_INITIALIZER_P (init)
4277 && CONSTRUCTOR_NELTS (init) == 1)
4278 {
4279 tree elt = CONSTRUCTOR_ELT (init, 0)->value;
4280 if (TREE_CODE (TREE_TYPE (elt)) == ARRAY_TYPE)
4281 {
4282 direct_init = DIRECT_LIST_INIT_P (init);
4283 init = elt;
4284 }
4285 }
4286
4287 /* If we have a braced-init-list or string constant, make sure that the array
4288 is big enough for all the initializers. */
4289 bool length_check = (init
4290 && (TREE_CODE (init) == STRING_CST
4291 || (TREE_CODE (init) == CONSTRUCTOR
4292 && CONSTRUCTOR_NELTS (init) > 0))
4293 && !TREE_CONSTANT (maxindex));
4294
4295 if (init
4296 && TREE_CODE (atype) == ARRAY_TYPE
4297 && TREE_CONSTANT (maxindex)
4298 && (from_array == 2
4299 ? vec_copy_assign_is_trivial (inner_elt_type, init)
4300 : !TYPE_NEEDS_CONSTRUCTING (type))
4301 && ((TREE_CODE (init) == CONSTRUCTOR
4302 && (BRACE_ENCLOSED_INITIALIZER_P (init)
4303 || (same_type_ignoring_top_level_qualifiers_p
4304 (atype, TREE_TYPE (init))))
4305 /* Don't do this if the CONSTRUCTOR might contain something
4306 that might throw and require us to clean up. */
4307 && (vec_safe_is_empty (CONSTRUCTOR_ELTS (init))
4308 || ! TYPE_HAS_NONTRIVIAL_DESTRUCTOR (inner_elt_type)))
4309 || from_array))
4310 {
4311 /* Do non-default initialization of trivial arrays resulting from
4312 brace-enclosed initializers. In this case, digest_init and
4313 store_constructor will handle the semantics for us. */
4314
4315 if (BRACE_ENCLOSED_INITIALIZER_P (init))
4316 init = digest_init (atype, init, complain);
4317 stmt_expr = build2 (INIT_EXPR, atype, base, init);
4318 return stmt_expr;
4319 }
4320
4321 maxindex = cp_convert (ptrdiff_type_node, maxindex, complain);
4322 maxindex = fold_simple (maxindex);
4323
4324 if (TREE_CODE (atype) == ARRAY_TYPE)
4325 {
4326 ptype = build_pointer_type (type);
4327 base = decay_conversion (base, complain);
4328 if (base == error_mark_node)
4329 return error_mark_node;
4330 base = cp_convert (ptype, base, complain);
4331 }
4332 else
4333 ptype = atype;
4334
4335 /* The code we are generating looks like:
4336 ({
4337 T* t1 = (T*) base;
4338 T* rval = t1;
4339 ptrdiff_t iterator = maxindex;
4340 try {
4341 for (; iterator != -1; --iterator) {
4342 ... initialize *t1 ...
4343 ++t1;
4344 }
4345 } catch (...) {
4346 ... destroy elements that were constructed ...
4347 }
4348 rval;
4349 })
4350
4351 We can omit the try and catch blocks if we know that the
4352 initialization will never throw an exception, or if the array
4353 elements do not have destructors. We can omit the loop completely if
4354 the elements of the array do not have constructors.
4355
4356 We actually wrap the entire body of the above in a STMT_EXPR, for
4357 tidiness.
4358
4359 When copying from array to another, when the array elements have
4360 only trivial copy constructors, we should use __builtin_memcpy
4361 rather than generating a loop. That way, we could take advantage
4362 of whatever cleverness the back end has for dealing with copies
4363 of blocks of memory. */
4364
4365 is_global = begin_init_stmts (&stmt_expr, &compound_stmt);
4366 destroy_temps = stmts_are_full_exprs_p ();
4367 current_stmt_tree ()->stmts_are_full_exprs_p = 0;
4368 rval = get_temp_regvar (ptype, base);
4369 base = get_temp_regvar (ptype, rval);
4370 iterator = get_temp_regvar (ptrdiff_type_node, maxindex);
4371
4372 /* If initializing one array from another, initialize element by
4373 element. We rely upon the below calls to do the argument
4374 checking. Evaluate the initializer before entering the try block. */
4375 if (from_array && init && TREE_CODE (init) != CONSTRUCTOR)
4376 {
4377 if (lvalue_kind (init) & clk_rvalueref)
4378 xvalue = true;
4379 base2 = decay_conversion (init, complain);
4380 if (base2 == error_mark_node)
4381 return error_mark_node;
4382 itype = TREE_TYPE (base2);
4383 base2 = get_temp_regvar (itype, base2);
4384 itype = TREE_TYPE (itype);
4385 }
4386
4387 /* Protect the entire array initialization so that we can destroy
4388 the partially constructed array if an exception is thrown.
4389 But don't do this if we're assigning. */
4390 if (flag_exceptions && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
4391 && from_array != 2)
4392 {
4393 try_block = begin_try_block ();
4394 }
4395
4396 /* Should we try to create a constant initializer? */
4397 bool try_const = (TREE_CODE (atype) == ARRAY_TYPE
4398 && TREE_CONSTANT (maxindex)
4399 && (init ? TREE_CODE (init) == CONSTRUCTOR
4400 : (type_has_constexpr_default_constructor
4401 (inner_elt_type)))
4402 && (literal_type_p (inner_elt_type)
4403 || TYPE_HAS_CONSTEXPR_CTOR (inner_elt_type)));
4404 vec<constructor_elt, va_gc> *const_vec = NULL;
4405 bool saw_non_const = false;
4406 /* If we're initializing a static array, we want to do static
4407 initialization of any elements with constant initializers even if
4408 some are non-constant. */
4409 bool do_static_init = (DECL_P (obase) && TREE_STATIC (obase));
4410
4411 bool empty_list = false;
4412 if (init && BRACE_ENCLOSED_INITIALIZER_P (init)
4413 && CONSTRUCTOR_NELTS (init) == 0)
4414 /* Skip over the handling of non-empty init lists. */
4415 empty_list = true;
4416
4417 /* Maybe pull out constant value when from_array? */
4418
4419 else if (init != NULL_TREE && TREE_CODE (init) == CONSTRUCTOR)
4420 {
4421 /* Do non-default initialization of non-trivial arrays resulting from
4422 brace-enclosed initializers. */
4423 unsigned HOST_WIDE_INT idx;
4424 tree field, elt;
4425 /* If the constructor already has the array type, it's been through
4426 digest_init, so we shouldn't try to do anything more. */
4427 bool digested = same_type_p (atype, TREE_TYPE (init));
4428 from_array = 0;
4429
4430 if (length_check)
4431 finish_length_check (atype, iterator, obase, CONSTRUCTOR_NELTS (init));
4432
4433 if (try_const)
4434 vec_alloc (const_vec, CONSTRUCTOR_NELTS (init));
4435
4436 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init), idx, field, elt)
4437 {
4438 tree baseref = build1 (INDIRECT_REF, type, base);
4439 tree one_init;
4440
4441 num_initialized_elts++;
4442
4443 current_stmt_tree ()->stmts_are_full_exprs_p = 1;
4444 if (digested)
4445 one_init = build2 (INIT_EXPR, type, baseref, elt);
4446 else if (MAYBE_CLASS_TYPE_P (type) || TREE_CODE (type) == ARRAY_TYPE)
4447 one_init = build_aggr_init (baseref, elt, 0, complain);
4448 else
4449 one_init = cp_build_modify_expr (input_location, baseref,
4450 NOP_EXPR, elt, complain);
4451 if (one_init == error_mark_node)
4452 errors = true;
4453 if (try_const)
4454 {
4455 if (!field)
4456 field = size_int (idx);
4457 tree e = maybe_constant_init (one_init);
4458 if (reduced_constant_expression_p (e))
4459 {
4460 CONSTRUCTOR_APPEND_ELT (const_vec, field, e);
4461 if (do_static_init)
4462 one_init = NULL_TREE;
4463 else
4464 one_init = build2 (INIT_EXPR, type, baseref, e);
4465 }
4466 else
4467 {
4468 if (do_static_init)
4469 {
4470 tree value = build_zero_init (TREE_TYPE (e), NULL_TREE,
4471 true);
4472 if (value)
4473 CONSTRUCTOR_APPEND_ELT (const_vec, field, value);
4474 }
4475 saw_non_const = true;
4476 }
4477 }
4478
4479 if (one_init)
4480 finish_expr_stmt (one_init);
4481 current_stmt_tree ()->stmts_are_full_exprs_p = 0;
4482
4483 one_init = cp_build_unary_op (PREINCREMENT_EXPR, base, false,
4484 complain);
4485 if (one_init == error_mark_node)
4486 errors = true;
4487 else
4488 finish_expr_stmt (one_init);
4489
4490 one_init = cp_build_unary_op (PREDECREMENT_EXPR, iterator, false,
4491 complain);
4492 if (one_init == error_mark_node)
4493 errors = true;
4494 else
4495 finish_expr_stmt (one_init);
4496 }
4497
4498 /* Any elements without explicit initializers get T{}. */
4499 empty_list = true;
4500 }
4501 else if (init && TREE_CODE (init) == STRING_CST)
4502 {
4503 /* Check that the array is at least as long as the string. */
4504 if (length_check)
4505 finish_length_check (atype, iterator, obase,
4506 TREE_STRING_LENGTH (init));
4507 tree length = build_int_cst (ptrdiff_type_node,
4508 TREE_STRING_LENGTH (init));
4509
4510 /* Copy the string to the first part of the array. */
4511 tree alias_set = build_int_cst (build_pointer_type (type), 0);
4512 tree lhs = build2 (MEM_REF, TREE_TYPE (init), base, alias_set);
4513 tree stmt = build2 (MODIFY_EXPR, void_type_node, lhs, init);
4514 finish_expr_stmt (stmt);
4515
4516 /* Adjust the counter and pointer. */
4517 stmt = cp_build_binary_op (loc, MINUS_EXPR, iterator, length, complain);
4518 stmt = build2 (MODIFY_EXPR, void_type_node, iterator, stmt);
4519 finish_expr_stmt (stmt);
4520
4521 stmt = cp_build_binary_op (loc, PLUS_EXPR, base, length, complain);
4522 stmt = build2 (MODIFY_EXPR, void_type_node, base, stmt);
4523 finish_expr_stmt (stmt);
4524
4525 /* And set the rest of the array to NUL. */
4526 from_array = 0;
4527 explicit_value_init_p = true;
4528 }
4529 else if (from_array)
4530 {
4531 if (init)
4532 /* OK, we set base2 above. */;
4533 else if (CLASS_TYPE_P (type)
4534 && ! TYPE_HAS_DEFAULT_CONSTRUCTOR (type))
4535 {
4536 if (complain & tf_error)
4537 error ("initializer ends prematurely");
4538 errors = true;
4539 }
4540 }
4541
4542 /* Now, default-initialize any remaining elements. We don't need to
4543 do that if a) the type does not need constructing, or b) we've
4544 already initialized all the elements.
4545
4546 We do need to keep going if we're copying an array. */
4547
4548 if (try_const && !init)
4549 /* With a constexpr default constructor, which we checked for when
4550 setting try_const above, default-initialization is equivalent to
4551 value-initialization, and build_value_init gives us something more
4552 friendly to maybe_constant_init. */
4553 explicit_value_init_p = true;
4554 if (from_array
4555 || ((type_build_ctor_call (type) || init || explicit_value_init_p)
4556 && ! (tree_fits_shwi_p (maxindex)
4557 && (num_initialized_elts
4558 == tree_to_shwi (maxindex) + 1))))
4559 {
4560 /* If the ITERATOR is lesser or equal to -1, then we don't have to loop;
4561 we've already initialized all the elements. */
4562 tree for_stmt;
4563 tree elt_init;
4564 tree to;
4565
4566 for_stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
4567 finish_init_stmt (for_stmt);
4568 finish_for_cond (build2 (GT_EXPR, boolean_type_node, iterator,
4569 build_int_cst (TREE_TYPE (iterator), -1)),
4570 for_stmt, false, 0);
4571 elt_init = cp_build_unary_op (PREDECREMENT_EXPR, iterator, false,
4572 complain);
4573 if (elt_init == error_mark_node)
4574 errors = true;
4575 finish_for_expr (elt_init, for_stmt);
4576
4577 to = build1 (INDIRECT_REF, type, base);
4578
4579 /* If the initializer is {}, then all elements are initialized from T{}.
4580 But for non-classes, that's the same as value-initialization. */
4581 if (empty_list)
4582 {
4583 if (cxx_dialect >= cxx11 && AGGREGATE_TYPE_P (type))
4584 {
4585 init = build_constructor (init_list_type_node, NULL);
4586 }
4587 else
4588 {
4589 init = NULL_TREE;
4590 explicit_value_init_p = true;
4591 }
4592 }
4593
4594 if (from_array)
4595 {
4596 tree from;
4597
4598 if (base2)
4599 {
4600 from = build1 (INDIRECT_REF, itype, base2);
4601 if (xvalue)
4602 from = move (from);
4603 if (direct_init)
4604 from = build_tree_list (NULL_TREE, from);
4605 }
4606 else
4607 from = NULL_TREE;
4608
4609 if (TREE_CODE (type) == ARRAY_TYPE)
4610 elt_init = build_vec_init (to, NULL_TREE, from, /*val_init*/false,
4611 from_array, complain);
4612 else if (from_array == 2)
4613 elt_init = cp_build_modify_expr (input_location, to, NOP_EXPR,
4614 from, complain);
4615 else if (type_build_ctor_call (type))
4616 elt_init = build_aggr_init (to, from, 0, complain);
4617 else if (from)
4618 elt_init = cp_build_modify_expr (input_location, to, NOP_EXPR, from,
4619 complain);
4620 else
4621 gcc_unreachable ();
4622 }
4623 else if (TREE_CODE (type) == ARRAY_TYPE)
4624 {
4625 if (init && !BRACE_ENCLOSED_INITIALIZER_P (init))
4626 {
4627 if ((complain & tf_error))
4628 error_at (loc, "array must be initialized "
4629 "with a brace-enclosed initializer");
4630 elt_init = error_mark_node;
4631 }
4632 else
4633 elt_init = build_vec_init (build1 (INDIRECT_REF, type, base),
4634 0, init,
4635 explicit_value_init_p,
4636 0, complain);
4637 }
4638 else if (explicit_value_init_p)
4639 {
4640 elt_init = build_value_init (type, complain);
4641 if (elt_init != error_mark_node)
4642 elt_init = build2 (INIT_EXPR, type, to, elt_init);
4643 }
4644 else
4645 {
4646 gcc_assert (type_build_ctor_call (type) || init);
4647 if (CLASS_TYPE_P (type))
4648 elt_init = build_aggr_init (to, init, 0, complain);
4649 else
4650 {
4651 if (TREE_CODE (init) == TREE_LIST)
4652 init = build_x_compound_expr_from_list (init, ELK_INIT,
4653 complain);
4654 elt_init = (init == error_mark_node
4655 ? error_mark_node
4656 : build2 (INIT_EXPR, type, to, init));
4657 }
4658 }
4659
4660 if (elt_init == error_mark_node)
4661 errors = true;
4662
4663 if (try_const)
4664 {
4665 /* FIXME refs to earlier elts */
4666 tree e = maybe_constant_init (elt_init);
4667 if (reduced_constant_expression_p (e))
4668 {
4669 if (initializer_zerop (e))
4670 /* Don't fill the CONSTRUCTOR with zeros. */
4671 e = NULL_TREE;
4672 if (do_static_init)
4673 elt_init = NULL_TREE;
4674 }
4675 else
4676 {
4677 saw_non_const = true;
4678 if (do_static_init)
4679 e = build_zero_init (TREE_TYPE (e), NULL_TREE, true);
4680 else
4681 e = NULL_TREE;
4682 }
4683
4684 if (e)
4685 {
4686 HOST_WIDE_INT last = tree_to_shwi (maxindex);
4687 if (num_initialized_elts <= last)
4688 {
4689 tree field = size_int (num_initialized_elts);
4690 if (num_initialized_elts != last)
4691 field = build2 (RANGE_EXPR, sizetype, field,
4692 size_int (last));
4693 CONSTRUCTOR_APPEND_ELT (const_vec, field, e);
4694 }
4695 }
4696 }
4697
4698 current_stmt_tree ()->stmts_are_full_exprs_p = 1;
4699 if (elt_init && !errors)
4700 finish_expr_stmt (elt_init);
4701 current_stmt_tree ()->stmts_are_full_exprs_p = 0;
4702
4703 finish_expr_stmt (cp_build_unary_op (PREINCREMENT_EXPR, base, false,
4704 complain));
4705 if (base2)
4706 finish_expr_stmt (cp_build_unary_op (PREINCREMENT_EXPR, base2, false,
4707 complain));
4708
4709 finish_for_stmt (for_stmt);
4710 }
4711
4712 /* Make sure to cleanup any partially constructed elements. */
4713 if (flag_exceptions && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
4714 && from_array != 2)
4715 {
4716 tree e;
4717 tree m = cp_build_binary_op (input_location,
4718 MINUS_EXPR, maxindex, iterator,
4719 complain);
4720
4721 /* Flatten multi-dimensional array since build_vec_delete only
4722 expects one-dimensional array. */
4723 if (TREE_CODE (type) == ARRAY_TYPE)
4724 m = cp_build_binary_op (input_location,
4725 MULT_EXPR, m,
4726 /* Avoid mixing signed and unsigned. */
4727 convert (TREE_TYPE (m),
4728 array_type_nelts_total (type)),
4729 complain);
4730
4731 finish_cleanup_try_block (try_block);
4732 e = build_vec_delete_1 (input_location, rval, m,
4733 inner_elt_type, sfk_complete_destructor,
4734 /*use_global_delete=*/0, complain);
4735 if (e == error_mark_node)
4736 errors = true;
4737 finish_cleanup (e, try_block);
4738 }
4739
4740 /* The value of the array initialization is the array itself, RVAL
4741 is a pointer to the first element. */
4742 finish_stmt_expr_expr (rval, stmt_expr);
4743
4744 stmt_expr = finish_init_stmts (is_global, stmt_expr, compound_stmt);
4745
4746 current_stmt_tree ()->stmts_are_full_exprs_p = destroy_temps;
4747
4748 if (errors)
4749 return error_mark_node;
4750
4751 if (try_const)
4752 {
4753 if (!saw_non_const)
4754 {
4755 tree const_init = build_constructor (atype, const_vec);
4756 return build2 (INIT_EXPR, atype, obase, const_init);
4757 }
4758 else if (do_static_init && !vec_safe_is_empty (const_vec))
4759 DECL_INITIAL (obase) = build_constructor (atype, const_vec);
4760 else
4761 vec_free (const_vec);
4762 }
4763
4764 /* Now make the result have the correct type. */
4765 if (TREE_CODE (atype) == ARRAY_TYPE)
4766 {
4767 atype = build_pointer_type (atype);
4768 stmt_expr = build1 (NOP_EXPR, atype, stmt_expr);
4769 stmt_expr = cp_build_fold_indirect_ref (stmt_expr);
4770 TREE_NO_WARNING (stmt_expr) = 1;
4771 }
4772
4773 return stmt_expr;
4774 }
4775
4776 /* Call the DTOR_KIND destructor for EXP. FLAGS are as for
4777 build_delete. */
4778
4779 static tree
build_dtor_call(tree exp,special_function_kind dtor_kind,int flags,tsubst_flags_t complain)4780 build_dtor_call (tree exp, special_function_kind dtor_kind, int flags,
4781 tsubst_flags_t complain)
4782 {
4783 tree name;
4784 switch (dtor_kind)
4785 {
4786 case sfk_complete_destructor:
4787 name = complete_dtor_identifier;
4788 break;
4789
4790 case sfk_base_destructor:
4791 name = base_dtor_identifier;
4792 break;
4793
4794 case sfk_deleting_destructor:
4795 name = deleting_dtor_identifier;
4796 break;
4797
4798 default:
4799 gcc_unreachable ();
4800 }
4801
4802 return build_special_member_call (exp, name,
4803 /*args=*/NULL,
4804 /*binfo=*/TREE_TYPE (exp),
4805 flags,
4806 complain);
4807 }
4808
4809 /* Generate a call to a destructor. TYPE is the type to cast ADDR to.
4810 ADDR is an expression which yields the store to be destroyed.
4811 AUTO_DELETE is the name of the destructor to call, i.e., either
4812 sfk_complete_destructor, sfk_base_destructor, or
4813 sfk_deleting_destructor.
4814
4815 FLAGS is the logical disjunction of zero or more LOOKUP_
4816 flags. See cp-tree.h for more info. */
4817
4818 tree
build_delete(location_t loc,tree otype,tree addr,special_function_kind auto_delete,int flags,int use_global_delete,tsubst_flags_t complain)4819 build_delete (location_t loc, tree otype, tree addr,
4820 special_function_kind auto_delete,
4821 int flags, int use_global_delete, tsubst_flags_t complain)
4822 {
4823 tree expr;
4824
4825 if (addr == error_mark_node)
4826 return error_mark_node;
4827
4828 tree type = TYPE_MAIN_VARIANT (otype);
4829
4830 /* Can happen when CURRENT_EXCEPTION_OBJECT gets its type
4831 set to `error_mark_node' before it gets properly cleaned up. */
4832 if (type == error_mark_node)
4833 return error_mark_node;
4834
4835 if (TYPE_PTR_P (type))
4836 type = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4837
4838 if (TREE_CODE (type) == ARRAY_TYPE)
4839 {
4840 if (TYPE_DOMAIN (type) == NULL_TREE)
4841 {
4842 if (complain & tf_error)
4843 error_at (loc, "unknown array size in delete");
4844 return error_mark_node;
4845 }
4846 return build_vec_delete (loc, addr, array_type_nelts (type),
4847 auto_delete, use_global_delete, complain);
4848 }
4849
4850 bool deleting = (auto_delete == sfk_deleting_destructor);
4851 gcc_assert (deleting == !(flags & LOOKUP_DESTRUCTOR));
4852
4853 if (TYPE_PTR_P (otype))
4854 {
4855 addr = mark_rvalue_use (addr);
4856
4857 /* We don't want to warn about delete of void*, only other
4858 incomplete types. Deleting other incomplete types
4859 invokes undefined behavior, but it is not ill-formed, so
4860 compile to something that would even do The Right Thing
4861 (TM) should the type have a trivial dtor and no delete
4862 operator. */
4863 if (!VOID_TYPE_P (type))
4864 {
4865 complete_type (type);
4866 if (deleting
4867 && !verify_type_context (loc, TCTX_DEALLOCATION, type,
4868 !(complain & tf_error)))
4869 return error_mark_node;
4870
4871 if (!COMPLETE_TYPE_P (type))
4872 {
4873 if (complain & tf_warning)
4874 {
4875 auto_diagnostic_group d;
4876 if (warning_at (loc, OPT_Wdelete_incomplete,
4877 "possible problem detected in invocation of "
4878 "%<operator delete%>"))
4879 {
4880 cxx_incomplete_type_diagnostic (addr, type, DK_WARNING);
4881 inform (loc,
4882 "neither the destructor nor the class-specific "
4883 "%<operator delete%> will be called, even if "
4884 "they are declared when the class is defined");
4885 }
4886 }
4887 }
4888 else if (deleting && warn_delnonvdtor
4889 && MAYBE_CLASS_TYPE_P (type) && !CLASSTYPE_FINAL (type)
4890 && TYPE_POLYMORPHIC_P (type))
4891 {
4892 tree dtor = CLASSTYPE_DESTRUCTOR (type);
4893 if (!dtor || !DECL_VINDEX (dtor))
4894 {
4895 if (CLASSTYPE_PURE_VIRTUALS (type))
4896 warning_at (loc, OPT_Wdelete_non_virtual_dtor,
4897 "deleting object of abstract class type %qT"
4898 " which has non-virtual destructor"
4899 " will cause undefined behavior", type);
4900 else
4901 warning_at (loc, OPT_Wdelete_non_virtual_dtor,
4902 "deleting object of polymorphic class type %qT"
4903 " which has non-virtual destructor"
4904 " might cause undefined behavior", type);
4905 }
4906 }
4907 }
4908
4909 /* Throw away const and volatile on target type of addr. */
4910 addr = convert_force (build_pointer_type (type), addr, 0, complain);
4911 }
4912 else
4913 {
4914 /* Don't check PROTECT here; leave that decision to the
4915 destructor. If the destructor is accessible, call it,
4916 else report error. */
4917 addr = cp_build_addr_expr (addr, complain);
4918 if (addr == error_mark_node)
4919 return error_mark_node;
4920
4921 addr = convert_force (build_pointer_type (type), addr, 0, complain);
4922 }
4923
4924 if (deleting)
4925 /* We will use ADDR multiple times so we must save it. */
4926 addr = save_expr (addr);
4927
4928 bool virtual_p = false;
4929 if (type_build_dtor_call (type))
4930 {
4931 if (CLASSTYPE_LAZY_DESTRUCTOR (type))
4932 lazily_declare_fn (sfk_destructor, type);
4933 virtual_p = DECL_VIRTUAL_P (CLASSTYPE_DESTRUCTOR (type));
4934 }
4935
4936 tree head = NULL_TREE;
4937 tree do_delete = NULL_TREE;
4938 bool destroying_delete = false;
4939
4940 if (!deleting)
4941 {
4942 /* Leave do_delete null. */
4943 }
4944 /* For `::delete x', we must not use the deleting destructor
4945 since then we would not be sure to get the global `operator
4946 delete'. */
4947 else if (use_global_delete)
4948 {
4949 head = get_target_expr (build_headof (addr));
4950 /* Delete the object. */
4951 do_delete = build_op_delete_call (DELETE_EXPR,
4952 head,
4953 cxx_sizeof_nowarn (type),
4954 /*global_p=*/true,
4955 /*placement=*/NULL_TREE,
4956 /*alloc_fn=*/NULL_TREE,
4957 complain);
4958 /* Otherwise, treat this like a complete object destructor
4959 call. */
4960 auto_delete = sfk_complete_destructor;
4961 }
4962 /* If the destructor is non-virtual, there is no deleting
4963 variant. Instead, we must explicitly call the appropriate
4964 `operator delete' here. */
4965 else if (!virtual_p)
4966 {
4967 /* Build the call. */
4968 do_delete = build_op_delete_call (DELETE_EXPR,
4969 addr,
4970 cxx_sizeof_nowarn (type),
4971 /*global_p=*/false,
4972 /*placement=*/NULL_TREE,
4973 /*alloc_fn=*/NULL_TREE,
4974 complain);
4975 /* Call the complete object destructor. */
4976 auto_delete = sfk_complete_destructor;
4977 if (do_delete != error_mark_node)
4978 {
4979 tree fn = get_callee_fndecl (do_delete);
4980 destroying_delete = destroying_delete_p (fn);
4981 }
4982 }
4983 else if (TYPE_GETS_REG_DELETE (type))
4984 {
4985 /* Make sure we have access to the member op delete, even though
4986 we'll actually be calling it from the destructor. */
4987 build_op_delete_call (DELETE_EXPR, addr, cxx_sizeof_nowarn (type),
4988 /*global_p=*/false,
4989 /*placement=*/NULL_TREE,
4990 /*alloc_fn=*/NULL_TREE,
4991 complain);
4992 }
4993
4994 if (!destroying_delete && type_build_dtor_call (type))
4995 expr = build_dtor_call (cp_build_fold_indirect_ref (addr),
4996 auto_delete, flags, complain);
4997 else
4998 expr = build_trivial_dtor_call (addr);
4999 if (expr == error_mark_node)
5000 return error_mark_node;
5001
5002 if (!deleting)
5003 {
5004 protected_set_expr_location (expr, loc);
5005 return expr;
5006 }
5007
5008 if (do_delete)
5009 {
5010 tree do_delete_call_expr = extract_call_expr (do_delete);
5011 if (TREE_CODE (do_delete_call_expr) == CALL_EXPR)
5012 CALL_FROM_NEW_OR_DELETE_P (do_delete_call_expr) = 1;
5013 }
5014
5015 if (do_delete && !TREE_SIDE_EFFECTS (expr))
5016 expr = do_delete;
5017 else if (do_delete)
5018 /* The delete operator must be called, regardless of whether
5019 the destructor throws.
5020
5021 [expr.delete]/7 The deallocation function is called
5022 regardless of whether the destructor for the object or some
5023 element of the array throws an exception. */
5024 expr = build2 (TRY_FINALLY_EXPR, void_type_node, expr, do_delete);
5025
5026 /* We need to calculate this before the dtor changes the vptr. */
5027 if (head)
5028 expr = build2 (COMPOUND_EXPR, void_type_node, head, expr);
5029
5030 /* Handle deleting a null pointer. */
5031 warning_sentinel s (warn_address);
5032 tree ifexp = cp_build_binary_op (loc, NE_EXPR, addr,
5033 nullptr_node, complain);
5034 ifexp = cp_fully_fold (ifexp);
5035
5036 if (ifexp == error_mark_node)
5037 return error_mark_node;
5038 /* This is a compiler generated comparison, don't emit
5039 e.g. -Wnonnull-compare warning for it. */
5040 else if (TREE_CODE (ifexp) == NE_EXPR)
5041 TREE_NO_WARNING (ifexp) = 1;
5042
5043 if (!integer_nonzerop (ifexp))
5044 expr = build3 (COND_EXPR, void_type_node, ifexp, expr, void_node);
5045
5046 protected_set_expr_location (expr, loc);
5047 return expr;
5048 }
5049
5050 /* At the beginning of a destructor, push cleanups that will call the
5051 destructors for our base classes and members.
5052
5053 Called from begin_destructor_body. */
5054
5055 void
push_base_cleanups(void)5056 push_base_cleanups (void)
5057 {
5058 tree binfo, base_binfo;
5059 int i;
5060 tree member;
5061 tree expr;
5062 vec<tree, va_gc> *vbases;
5063
5064 /* Run destructors for all virtual baseclasses. */
5065 if (!ABSTRACT_CLASS_TYPE_P (current_class_type)
5066 && CLASSTYPE_VBASECLASSES (current_class_type))
5067 {
5068 tree cond = (condition_conversion
5069 (build2 (BIT_AND_EXPR, integer_type_node,
5070 current_in_charge_parm,
5071 integer_two_node)));
5072
5073 /* The CLASSTYPE_VBASECLASSES vector is in initialization
5074 order, which is also the right order for pushing cleanups. */
5075 for (vbases = CLASSTYPE_VBASECLASSES (current_class_type), i = 0;
5076 vec_safe_iterate (vbases, i, &base_binfo); i++)
5077 {
5078 if (type_build_dtor_call (BINFO_TYPE (base_binfo)))
5079 {
5080 expr = build_special_member_call (current_class_ref,
5081 base_dtor_identifier,
5082 NULL,
5083 base_binfo,
5084 (LOOKUP_NORMAL
5085 | LOOKUP_NONVIRTUAL),
5086 tf_warning_or_error);
5087 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (BINFO_TYPE (base_binfo)))
5088 {
5089 expr = build3 (COND_EXPR, void_type_node, cond,
5090 expr, void_node);
5091 finish_decl_cleanup (NULL_TREE, expr);
5092 }
5093 }
5094 }
5095 }
5096
5097 /* Take care of the remaining baseclasses. */
5098 for (binfo = TYPE_BINFO (current_class_type), i = 0;
5099 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
5100 {
5101 if (BINFO_VIRTUAL_P (base_binfo)
5102 || !type_build_dtor_call (BINFO_TYPE (base_binfo)))
5103 continue;
5104
5105 expr = build_special_member_call (current_class_ref,
5106 base_dtor_identifier,
5107 NULL, base_binfo,
5108 LOOKUP_NORMAL | LOOKUP_NONVIRTUAL,
5109 tf_warning_or_error);
5110 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (BINFO_TYPE (base_binfo)))
5111 finish_decl_cleanup (NULL_TREE, expr);
5112 }
5113
5114 /* Don't automatically destroy union members. */
5115 if (TREE_CODE (current_class_type) == UNION_TYPE)
5116 return;
5117
5118 for (member = TYPE_FIELDS (current_class_type); member;
5119 member = DECL_CHAIN (member))
5120 {
5121 tree this_type = TREE_TYPE (member);
5122 if (this_type == error_mark_node
5123 || TREE_CODE (member) != FIELD_DECL
5124 || DECL_ARTIFICIAL (member))
5125 continue;
5126 if (ANON_AGGR_TYPE_P (this_type))
5127 continue;
5128 if (type_build_dtor_call (this_type))
5129 {
5130 tree this_member = (build_class_member_access_expr
5131 (current_class_ref, member,
5132 /*access_path=*/NULL_TREE,
5133 /*preserve_reference=*/false,
5134 tf_warning_or_error));
5135 expr = build_delete (input_location, this_type, this_member,
5136 sfk_complete_destructor,
5137 LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR|LOOKUP_NORMAL,
5138 0, tf_warning_or_error);
5139 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (this_type))
5140 finish_decl_cleanup (NULL_TREE, expr);
5141 }
5142 }
5143 }
5144
5145 /* Build a C++ vector delete expression.
5146 MAXINDEX is the number of elements to be deleted.
5147 ELT_SIZE is the nominal size of each element in the vector.
5148 BASE is the expression that should yield the store to be deleted.
5149 This function expands (or synthesizes) these calls itself.
5150 AUTO_DELETE_VEC says whether the container (vector) should be deallocated.
5151
5152 This also calls delete for virtual baseclasses of elements of the vector.
5153
5154 Update: MAXINDEX is no longer needed. The size can be extracted from the
5155 start of the vector for pointers, and from the type for arrays. We still
5156 use MAXINDEX for arrays because it happens to already have one of the
5157 values we'd have to extract. (We could use MAXINDEX with pointers to
5158 confirm the size, and trap if the numbers differ; not clear that it'd
5159 be worth bothering.) */
5160
5161 tree
build_vec_delete(location_t loc,tree base,tree maxindex,special_function_kind auto_delete_vec,int use_global_delete,tsubst_flags_t complain)5162 build_vec_delete (location_t loc, tree base, tree maxindex,
5163 special_function_kind auto_delete_vec,
5164 int use_global_delete, tsubst_flags_t complain)
5165 {
5166 tree type;
5167 tree rval;
5168 tree base_init = NULL_TREE;
5169
5170 type = TREE_TYPE (base);
5171
5172 if (TYPE_PTR_P (type))
5173 {
5174 /* Step back one from start of vector, and read dimension. */
5175 tree cookie_addr;
5176 tree size_ptr_type = build_pointer_type (sizetype);
5177
5178 base = mark_rvalue_use (base);
5179 if (TREE_SIDE_EFFECTS (base))
5180 {
5181 base_init = get_target_expr (base);
5182 base = TARGET_EXPR_SLOT (base_init);
5183 }
5184 type = strip_array_types (TREE_TYPE (type));
5185 cookie_addr = fold_build1_loc (loc, NEGATE_EXPR,
5186 sizetype, TYPE_SIZE_UNIT (sizetype));
5187 cookie_addr = fold_build_pointer_plus (fold_convert (size_ptr_type, base),
5188 cookie_addr);
5189 maxindex = cp_build_fold_indirect_ref (cookie_addr);
5190 }
5191 else if (TREE_CODE (type) == ARRAY_TYPE)
5192 {
5193 /* Get the total number of things in the array, maxindex is a
5194 bad name. */
5195 maxindex = array_type_nelts_total (type);
5196 type = strip_array_types (type);
5197 base = decay_conversion (base, complain);
5198 if (base == error_mark_node)
5199 return error_mark_node;
5200 if (TREE_SIDE_EFFECTS (base))
5201 {
5202 base_init = get_target_expr (base);
5203 base = TARGET_EXPR_SLOT (base_init);
5204 }
5205 }
5206 else
5207 {
5208 if (base != error_mark_node && !(complain & tf_error))
5209 error_at (loc,
5210 "type to vector delete is neither pointer or array type");
5211 return error_mark_node;
5212 }
5213
5214 rval = build_vec_delete_1 (loc, base, maxindex, type, auto_delete_vec,
5215 use_global_delete, complain);
5216 if (base_init && rval != error_mark_node)
5217 rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), base_init, rval);
5218
5219 protected_set_expr_location (rval, loc);
5220 return rval;
5221 }
5222
5223 #include "gt-cp-init.h"
5224