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 
589 	  processing_template_decl_sentinel ptds (/*reset*/false);
590 	  if (!currently_open_class (ctx))
591 	    {
592 	      if (!LOCAL_CLASS_P (ctx))
593 		push_to_top_level ();
594 	      else
595 		/* push_to_top_level would lose the necessary function context,
596 		   just reset processing_template_decl.  */
597 		processing_template_decl = 0;
598 	      push_nested_class (ctx);
599 	      push_deferring_access_checks (dk_no_deferred);
600 	      pushed = true;
601 	    }
602 
603 	  inject_this_parameter (ctx, TYPE_UNQUALIFIED);
604 
605 	  start_lambda_scope (member);
606 
607 	  /* Do deferred instantiation of the NSDMI.  */
608 	  init = (tsubst_copy_and_build
609 		  (init, DECL_TI_ARGS (member),
610 		   complain, member, /*function_p=*/false,
611 		   /*integral_constant_expression_p=*/false));
612 	  init = digest_nsdmi_init (member, init, complain);
613 
614 	  finish_lambda_scope ();
615 
616 	  DECL_INSTANTIATING_NSDMI_P (member) = 0;
617 
618 	  if (init != error_mark_node)
619 	    hash_map_safe_put<hm_ggc> (nsdmi_inst, member, init);
620 
621 	  if (pushed)
622 	    {
623 	      pop_deferring_access_checks ();
624 	      pop_nested_class ();
625 	      if (!LOCAL_CLASS_P (ctx))
626 		pop_from_top_level ();
627 	    }
628 
629 	  input_location = sloc;
630 	}
631     }
632   else
633     init = DECL_INITIAL (member);
634 
635   if (init && TREE_CODE (init) == DEFERRED_PARSE)
636     {
637       if (complain & tf_error)
638 	{
639 	  error ("default member initializer for %qD required before the end "
640 		 "of its enclosing class", member);
641 	  inform (location_of (init), "defined here");
642 	  DECL_INITIAL (member) = error_mark_node;
643 	}
644       init = error_mark_node;
645     }
646 
647   if (in_ctor)
648     {
649       current_class_ptr = save_ccp;
650       current_class_ref = save_ccr;
651     }
652   else
653     {
654       /* Use a PLACEHOLDER_EXPR when we don't have a 'this' parameter to
655 	 refer to; constexpr evaluation knows what to do with it.  */
656       current_class_ref = build0 (PLACEHOLDER_EXPR, DECL_CONTEXT (member));
657       current_class_ptr = build_address (current_class_ref);
658     }
659 
660   /* Strip redundant TARGET_EXPR so we don't need to remap it, and
661      so the aggregate init code below will see a CONSTRUCTOR.  */
662   bool simple_target = (init && SIMPLE_TARGET_EXPR_P (init));
663   if (simple_target)
664     init = TARGET_EXPR_INITIAL (init);
665   init = break_out_target_exprs (init, /*loc*/true);
666   if (in_ctor && init && TREE_CODE (init) == TARGET_EXPR)
667     /* This expresses the full initialization, prevent perform_member_init from
668        calling another constructor (58162).  */
669     TARGET_EXPR_DIRECT_INIT_P (init) = true;
670   if (simple_target && TREE_CODE (init) != CONSTRUCTOR)
671     /* Now put it back so C++17 copy elision works.  */
672     init = get_target_expr (init);
673 
674   current_class_ptr = save_ccp;
675   current_class_ref = save_ccr;
676   return init;
677 }
678 
679 /* Diagnose the flexible array MEMBER if its INITializer is non-null
680    and return true if so.  Otherwise return false.  */
681 
682 bool
maybe_reject_flexarray_init(tree member,tree init)683 maybe_reject_flexarray_init (tree member, tree init)
684 {
685   tree type = TREE_TYPE (member);
686 
687   if (!init
688       || TREE_CODE (type) != ARRAY_TYPE
689       || TYPE_DOMAIN (type))
690     return false;
691 
692   /* Point at the flexible array member declaration if it's initialized
693      in-class, and at the ctor if it's initialized in a ctor member
694      initializer list.  */
695   location_t loc;
696   if (DECL_INITIAL (member) == init
697       || !current_function_decl
698       || DECL_DEFAULTED_FN (current_function_decl))
699     loc = DECL_SOURCE_LOCATION (member);
700   else
701     loc = DECL_SOURCE_LOCATION (current_function_decl);
702 
703   error_at (loc, "initializer for flexible array member %q#D", member);
704   return true;
705 }
706 
707 /* If INIT's value can come from a call to std::initializer_list<T>::begin,
708    return that function.  Otherwise, NULL_TREE.  */
709 
710 static tree
find_list_begin(tree init)711 find_list_begin (tree init)
712 {
713   STRIP_NOPS (init);
714   while (TREE_CODE (init) == COMPOUND_EXPR)
715     init = TREE_OPERAND (init, 1);
716   STRIP_NOPS (init);
717   if (TREE_CODE (init) == COND_EXPR)
718     {
719       tree left = TREE_OPERAND (init, 1);
720       if (!left)
721 	left = TREE_OPERAND (init, 0);
722       left = find_list_begin (left);
723       if (left)
724 	return left;
725       return find_list_begin (TREE_OPERAND (init, 2));
726     }
727   if (TREE_CODE (init) == CALL_EXPR)
728     if (tree fn = get_callee_fndecl (init))
729       if (id_equal (DECL_NAME (fn), "begin")
730 	  && is_std_init_list (DECL_CONTEXT (fn)))
731 	return fn;
732   return NULL_TREE;
733 }
734 
735 /* If INIT initializing MEMBER is copying the address of the underlying array
736    of an initializer_list, warn.  */
737 
738 static void
maybe_warn_list_ctor(tree member,tree init)739 maybe_warn_list_ctor (tree member, tree init)
740 {
741   tree memtype = TREE_TYPE (member);
742   if (!init || !TYPE_PTR_P (memtype)
743       || !is_list_ctor (current_function_decl))
744     return;
745 
746   tree parms = FUNCTION_FIRST_USER_PARMTYPE (current_function_decl);
747   tree initlist = non_reference (TREE_VALUE (parms));
748   tree targs = CLASSTYPE_TI_ARGS (initlist);
749   tree elttype = TREE_VEC_ELT (targs, 0);
750 
751   if (!same_type_ignoring_top_level_qualifiers_p
752       (TREE_TYPE (memtype), elttype))
753     return;
754 
755   tree begin = find_list_begin (init);
756   if (!begin)
757     return;
758 
759   location_t loc = cp_expr_loc_or_input_loc (init);
760   warning_at (loc, OPT_Winit_list_lifetime,
761 	     "initializing %qD from %qE does not extend the lifetime "
762 	     "of the underlying array", member, begin);
763 }
764 
765 /* Initialize MEMBER, a FIELD_DECL, with INIT, a TREE_LIST of
766    arguments.  If TREE_LIST is void_type_node, an empty initializer
767    list was given; if NULL_TREE no initializer was given.  */
768 
769 static void
perform_member_init(tree member,tree init)770 perform_member_init (tree member, tree init)
771 {
772   tree decl;
773   tree type = TREE_TYPE (member);
774 
775   /* Use the non-static data member initializer if there was no
776      mem-initializer for this field.  */
777   if (init == NULL_TREE)
778     init = get_nsdmi (member, /*ctor*/true, tf_warning_or_error);
779 
780   if (init == error_mark_node)
781     return;
782 
783   /* Effective C++ rule 12 requires that all data members be
784      initialized.  */
785   if (warn_ecpp && init == NULL_TREE && TREE_CODE (type) != ARRAY_TYPE)
786     warning_at (DECL_SOURCE_LOCATION (current_function_decl), OPT_Weffc__,
787 		"%qD should be initialized in the member initialization list",
788 		member);
789 
790   /* Get an lvalue for the data member.  */
791   decl = build_class_member_access_expr (current_class_ref, member,
792 					 /*access_path=*/NULL_TREE,
793 					 /*preserve_reference=*/true,
794 					 tf_warning_or_error);
795   if (decl == error_mark_node)
796     return;
797 
798   if (warn_init_self && init && TREE_CODE (init) == TREE_LIST
799       && TREE_CHAIN (init) == NULL_TREE)
800     {
801       tree val = TREE_VALUE (init);
802       /* Handle references.  */
803       if (REFERENCE_REF_P (val))
804 	val = TREE_OPERAND (val, 0);
805       if (TREE_CODE (val) == COMPONENT_REF && TREE_OPERAND (val, 1) == member
806 	  && TREE_OPERAND (val, 0) == current_class_ref)
807 	warning_at (DECL_SOURCE_LOCATION (current_function_decl),
808 		    OPT_Winit_self, "%qD is initialized with itself",
809 		    member);
810     }
811 
812   if (array_of_unknown_bound_p (type))
813     {
814       maybe_reject_flexarray_init (member, init);
815       return;
816     }
817 
818   if (init && TREE_CODE (init) == TREE_LIST
819       && (DIRECT_LIST_INIT_P (TREE_VALUE (init))
820 	  /* FIXME C++20 parenthesized aggregate init (PR 92812).  */
821 	  || !(/* cxx_dialect >= cxx2a ? CP_AGGREGATE_TYPE_P (type) */
822 	       /* :  */CLASS_TYPE_P (type))))
823     init = build_x_compound_expr_from_list (init, ELK_MEM_INIT,
824 					    tf_warning_or_error);
825 
826   if (init == void_type_node)
827     {
828       /* mem() means value-initialization.  */
829       if (TREE_CODE (type) == ARRAY_TYPE)
830 	{
831 	  init = build_vec_init_expr (type, init, tf_warning_or_error);
832 	  init = build2 (INIT_EXPR, type, decl, init);
833 	  finish_expr_stmt (init);
834 	}
835       else
836 	{
837 	  tree value = build_value_init (type, tf_warning_or_error);
838 	  if (value == error_mark_node)
839 	    return;
840 	  init = build2 (INIT_EXPR, type, decl, value);
841 	  finish_expr_stmt (init);
842 	}
843     }
844   /* Deal with this here, as we will get confused if we try to call the
845      assignment op for an anonymous union.  This can happen in a
846      synthesized copy constructor.  */
847   else if (ANON_AGGR_TYPE_P (type))
848     {
849       if (init)
850 	{
851 	  init = build2 (INIT_EXPR, type, decl, TREE_VALUE (init));
852 	  finish_expr_stmt (init);
853 	}
854     }
855   else if (init
856 	   && (TYPE_REF_P (type)
857 	       || (TREE_CODE (init) == CONSTRUCTOR
858 		   && (CP_AGGREGATE_TYPE_P (type)
859 		       || is_std_init_list (type)))))
860     {
861       /* With references and list-initialization, we need to deal with
862 	 extending temporary lifetimes.  12.2p5: "A temporary bound to a
863 	 reference member in a constructor’s ctor-initializer (12.6.2)
864 	 persists until the constructor exits."  */
865       unsigned i; tree t;
866       releasing_vec cleanups;
867       if (!same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (init), type))
868 	{
869 	  if (BRACE_ENCLOSED_INITIALIZER_P (init)
870 	      && CP_AGGREGATE_TYPE_P (type))
871 	    init = reshape_init (type, init, tf_warning_or_error);
872 	  init = digest_init (type, init, tf_warning_or_error);
873 	}
874       if (init == error_mark_node)
875 	return;
876       if (DECL_SIZE (member) && integer_zerop (DECL_SIZE (member))
877 	  && !TREE_SIDE_EFFECTS (init))
878 	/* Don't add trivial initialization of an empty base/field, as they
879 	   might not be ordered the way the back-end expects.  */
880 	return;
881       /* A FIELD_DECL doesn't really have a suitable lifetime, but
882 	 make_temporary_var_for_ref_to_temp will treat it as automatic and
883 	 set_up_extended_ref_temp wants to use the decl in a warning.  */
884       init = extend_ref_init_temps (member, init, &cleanups);
885       if (TREE_CODE (type) == ARRAY_TYPE
886 	  && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (type)))
887 	init = build_vec_init_expr (type, init, tf_warning_or_error);
888       init = build2 (INIT_EXPR, type, decl, init);
889       finish_expr_stmt (init);
890       FOR_EACH_VEC_ELT (*cleanups, i, t)
891 	push_cleanup (decl, t, false);
892     }
893   else if (type_build_ctor_call (type)
894 	   || (init && CLASS_TYPE_P (strip_array_types (type))))
895     {
896       if (TREE_CODE (type) == ARRAY_TYPE)
897 	{
898 	  if (init == NULL_TREE
899 	      || same_type_ignoring_top_level_qualifiers_p (type,
900 							    TREE_TYPE (init)))
901 	    {
902 	      if (TYPE_DOMAIN (type) && TYPE_MAX_VALUE (TYPE_DOMAIN (type)))
903 		{
904 		  /* Initialize the array only if it's not a flexible
905 		     array member (i.e., if it has an upper bound).  */
906 		  init = build_vec_init_expr (type, init, tf_warning_or_error);
907 		  init = build2 (INIT_EXPR, type, decl, init);
908 		  finish_expr_stmt (init);
909 		}
910 	    }
911 	  else
912 	    error ("invalid initializer for array member %q#D", member);
913 	}
914       else
915 	{
916 	  int flags = LOOKUP_NORMAL;
917 	  if (DECL_DEFAULTED_FN (current_function_decl))
918 	    flags |= LOOKUP_DEFAULTED;
919 	  if (CP_TYPE_CONST_P (type)
920 	      && init == NULL_TREE
921 	      && default_init_uninitialized_part (type))
922 	    {
923 	      /* TYPE_NEEDS_CONSTRUCTING can be set just because we have a
924 		 vtable; still give this diagnostic.  */
925 	      auto_diagnostic_group d;
926 	      if (permerror (DECL_SOURCE_LOCATION (current_function_decl),
927 			     "uninitialized const member in %q#T", type))
928 		inform (DECL_SOURCE_LOCATION (member),
929 			"%q#D should be initialized", member );
930 	    }
931 	  finish_expr_stmt (build_aggr_init (decl, init, flags,
932 					     tf_warning_or_error));
933 	}
934     }
935   else
936     {
937       if (init == NULL_TREE)
938 	{
939 	  tree core_type;
940 	  /* member traversal: note it leaves init NULL */
941 	  if (TYPE_REF_P (type))
942 	    {
943 	      auto_diagnostic_group d;
944 	      if (permerror (DECL_SOURCE_LOCATION (current_function_decl),
945 			     "uninitialized reference member in %q#T", type))
946 		inform (DECL_SOURCE_LOCATION (member),
947 			"%q#D should be initialized", member);
948 	    }
949 	  else if (CP_TYPE_CONST_P (type))
950 	    {
951 	      auto_diagnostic_group d;
952 	      if (permerror (DECL_SOURCE_LOCATION (current_function_decl),
953 			     "uninitialized const member in %q#T", type))
954 		  inform (DECL_SOURCE_LOCATION (member),
955 			  "%q#D should be initialized", member );
956 	    }
957 
958 	  core_type = strip_array_types (type);
959 
960 	  if (CLASS_TYPE_P (core_type)
961 	      && (CLASSTYPE_READONLY_FIELDS_NEED_INIT (core_type)
962 		  || CLASSTYPE_REF_FIELDS_NEED_INIT (core_type)))
963 	    diagnose_uninitialized_cst_or_ref_member (core_type,
964 						      /*using_new=*/false,
965 						      /*complain=*/true);
966 	}
967 
968       maybe_warn_list_ctor (member, init);
969 
970       if (init)
971 	finish_expr_stmt (cp_build_modify_expr (input_location, decl,
972 						INIT_EXPR, init,
973 						tf_warning_or_error));
974     }
975 
976   if (type_build_dtor_call (type))
977     {
978       tree expr;
979 
980       expr = build_class_member_access_expr (current_class_ref, member,
981 					     /*access_path=*/NULL_TREE,
982 					     /*preserve_reference=*/false,
983 					     tf_warning_or_error);
984       expr = build_delete (input_location,
985 			   type, expr, sfk_complete_destructor,
986 			   LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR, 0,
987 			   tf_warning_or_error);
988 
989       if (expr != error_mark_node
990 	  && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
991 	finish_eh_cleanup (expr);
992     }
993 }
994 
995 /* Returns a TREE_LIST containing (as the TREE_PURPOSE of each node) all
996    the FIELD_DECLs on the TYPE_FIELDS list for T, in reverse order.  */
997 
998 static tree
build_field_list(tree t,tree list,int * uses_unions_or_anon_p)999 build_field_list (tree t, tree list, int *uses_unions_or_anon_p)
1000 {
1001   tree fields;
1002 
1003   /* Note whether or not T is a union.  */
1004   if (TREE_CODE (t) == UNION_TYPE)
1005     *uses_unions_or_anon_p = 1;
1006 
1007   for (fields = TYPE_FIELDS (t); fields; fields = DECL_CHAIN (fields))
1008     {
1009       tree fieldtype;
1010 
1011       /* Skip CONST_DECLs for enumeration constants and so forth.  */
1012       if (TREE_CODE (fields) != FIELD_DECL || DECL_ARTIFICIAL (fields))
1013 	continue;
1014 
1015       fieldtype = TREE_TYPE (fields);
1016 
1017       /* For an anonymous struct or union, we must recursively
1018 	 consider the fields of the anonymous type.  They can be
1019 	 directly initialized from the constructor.  */
1020       if (ANON_AGGR_TYPE_P (fieldtype))
1021 	{
1022 	  /* Add this field itself.  Synthesized copy constructors
1023 	     initialize the entire aggregate.  */
1024 	  list = tree_cons (fields, NULL_TREE, list);
1025 	  /* And now add the fields in the anonymous aggregate.  */
1026 	  list = build_field_list (fieldtype, list, uses_unions_or_anon_p);
1027 	  *uses_unions_or_anon_p = 1;
1028 	}
1029       /* Add this field.  */
1030       else if (DECL_NAME (fields))
1031 	list = tree_cons (fields, NULL_TREE, list);
1032     }
1033 
1034   return list;
1035 }
1036 
1037 /* Return the innermost aggregate scope for FIELD, whether that is
1038    the enclosing class or an anonymous aggregate within it.  */
1039 
1040 static tree
innermost_aggr_scope(tree field)1041 innermost_aggr_scope (tree field)
1042 {
1043   if (ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1044     return TREE_TYPE (field);
1045   else
1046     return DECL_CONTEXT (field);
1047 }
1048 
1049 /* The MEM_INITS are a TREE_LIST.  The TREE_PURPOSE of each list gives
1050    a FIELD_DECL or BINFO in T that needs initialization.  The
1051    TREE_VALUE gives the initializer, or list of initializer arguments.
1052 
1053    Return a TREE_LIST containing all of the initializations required
1054    for T, in the order in which they should be performed.  The output
1055    list has the same format as the input.  */
1056 
1057 static tree
sort_mem_initializers(tree t,tree mem_inits)1058 sort_mem_initializers (tree t, tree mem_inits)
1059 {
1060   tree init;
1061   tree base, binfo, base_binfo;
1062   tree sorted_inits;
1063   tree next_subobject;
1064   vec<tree, va_gc> *vbases;
1065   int i;
1066   int uses_unions_or_anon_p = 0;
1067 
1068   /* Build up a list of initializations.  The TREE_PURPOSE of entry
1069      will be the subobject (a FIELD_DECL or BINFO) to initialize.  The
1070      TREE_VALUE will be the constructor arguments, or NULL if no
1071      explicit initialization was provided.  */
1072   sorted_inits = NULL_TREE;
1073 
1074   /* Process the virtual bases.  */
1075   for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
1076        vec_safe_iterate (vbases, i, &base); i++)
1077     sorted_inits = tree_cons (base, NULL_TREE, sorted_inits);
1078 
1079   /* Process the direct bases.  */
1080   for (binfo = TYPE_BINFO (t), i = 0;
1081        BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
1082     if (!BINFO_VIRTUAL_P (base_binfo))
1083       sorted_inits = tree_cons (base_binfo, NULL_TREE, sorted_inits);
1084 
1085   /* Process the non-static data members.  */
1086   sorted_inits = build_field_list (t, sorted_inits, &uses_unions_or_anon_p);
1087   /* Reverse the entire list of initializations, so that they are in
1088      the order that they will actually be performed.  */
1089   sorted_inits = nreverse (sorted_inits);
1090 
1091   /* If the user presented the initializers in an order different from
1092      that in which they will actually occur, we issue a warning.  Keep
1093      track of the next subobject which can be explicitly initialized
1094      without issuing a warning.  */
1095   next_subobject = sorted_inits;
1096 
1097   /* Go through the explicit initializers, filling in TREE_PURPOSE in
1098      the SORTED_INITS.  */
1099   for (init = mem_inits; init; init = TREE_CHAIN (init))
1100     {
1101       tree subobject;
1102       tree subobject_init;
1103 
1104       subobject = TREE_PURPOSE (init);
1105 
1106       /* If the explicit initializers are in sorted order, then
1107 	 SUBOBJECT will be NEXT_SUBOBJECT, or something following
1108 	 it.  */
1109       for (subobject_init = next_subobject;
1110 	   subobject_init;
1111 	   subobject_init = TREE_CHAIN (subobject_init))
1112 	if (TREE_PURPOSE (subobject_init) == subobject)
1113 	  break;
1114 
1115       /* Issue a warning if the explicit initializer order does not
1116 	 match that which will actually occur.
1117 	 ??? Are all these on the correct lines?  */
1118       if (warn_reorder && !subobject_init)
1119 	{
1120 	  if (TREE_CODE (TREE_PURPOSE (next_subobject)) == FIELD_DECL)
1121 	    warning_at (DECL_SOURCE_LOCATION (TREE_PURPOSE (next_subobject)),
1122 			OPT_Wreorder, "%qD will be initialized after",
1123 			TREE_PURPOSE (next_subobject));
1124 	  else
1125 	    warning (OPT_Wreorder, "base %qT will be initialized after",
1126 		     TREE_PURPOSE (next_subobject));
1127 	  if (TREE_CODE (subobject) == FIELD_DECL)
1128 	    warning_at (DECL_SOURCE_LOCATION (subobject),
1129 			OPT_Wreorder, "  %q#D", subobject);
1130 	  else
1131 	    warning (OPT_Wreorder, "  base %qT", subobject);
1132 	  warning_at (DECL_SOURCE_LOCATION (current_function_decl),
1133 		      OPT_Wreorder, "  when initialized here");
1134 	}
1135 
1136       /* Look again, from the beginning of the list.  */
1137       if (!subobject_init)
1138 	{
1139 	  subobject_init = sorted_inits;
1140 	  while (TREE_PURPOSE (subobject_init) != subobject)
1141 	    subobject_init = TREE_CHAIN (subobject_init);
1142 	}
1143 
1144       /* It is invalid to initialize the same subobject more than
1145 	 once.  */
1146       if (TREE_VALUE (subobject_init))
1147 	{
1148 	  if (TREE_CODE (subobject) == FIELD_DECL)
1149 	    error_at (DECL_SOURCE_LOCATION (current_function_decl),
1150 		      "multiple initializations given for %qD",
1151 		      subobject);
1152 	  else
1153 	    error_at (DECL_SOURCE_LOCATION (current_function_decl),
1154 		      "multiple initializations given for base %qT",
1155 		      subobject);
1156 	}
1157 
1158       /* Record the initialization.  */
1159       TREE_VALUE (subobject_init) = TREE_VALUE (init);
1160       next_subobject = subobject_init;
1161     }
1162 
1163   /* [class.base.init]
1164 
1165      If a ctor-initializer specifies more than one mem-initializer for
1166      multiple members of the same union (including members of
1167      anonymous unions), the ctor-initializer is ill-formed.
1168 
1169      Here we also splice out uninitialized union members.  */
1170   if (uses_unions_or_anon_p)
1171     {
1172       tree *last_p = NULL;
1173       tree *p;
1174       for (p = &sorted_inits; *p; )
1175 	{
1176 	  tree field;
1177 	  tree ctx;
1178 
1179 	  init = *p;
1180 
1181 	  field = TREE_PURPOSE (init);
1182 
1183 	  /* Skip base classes.  */
1184 	  if (TREE_CODE (field) != FIELD_DECL)
1185 	    goto next;
1186 
1187 	  /* If this is an anonymous aggregate with no explicit initializer,
1188 	     splice it out.  */
1189 	  if (!TREE_VALUE (init) && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1190 	    goto splice;
1191 
1192 	  /* See if this field is a member of a union, or a member of a
1193 	     structure contained in a union, etc.  */
1194 	  ctx = innermost_aggr_scope (field);
1195 
1196 	  /* If this field is not a member of a union, skip it.  */
1197 	  if (TREE_CODE (ctx) != UNION_TYPE
1198 	      && !ANON_AGGR_TYPE_P (ctx))
1199 	    goto next;
1200 
1201 	  /* If this union member has no explicit initializer and no NSDMI,
1202 	     splice it out.  */
1203 	  if (TREE_VALUE (init) || DECL_INITIAL (field))
1204 	    /* OK.  */;
1205 	  else
1206 	    goto splice;
1207 
1208 	  /* It's only an error if we have two initializers for the same
1209 	     union type.  */
1210 	  if (!last_p)
1211 	    {
1212 	      last_p = p;
1213 	      goto next;
1214 	    }
1215 
1216 	  /* See if LAST_FIELD and the field initialized by INIT are
1217 	     members of the same union (or the union itself). If so, there's
1218 	     a problem, unless they're actually members of the same structure
1219 	     which is itself a member of a union.  For example, given:
1220 
1221 	       union { struct { int i; int j; }; };
1222 
1223 	     initializing both `i' and `j' makes sense.  */
1224 	  ctx = common_enclosing_class
1225 	    (innermost_aggr_scope (field),
1226 	     innermost_aggr_scope (TREE_PURPOSE (*last_p)));
1227 
1228 	  if (ctx && (TREE_CODE (ctx) == UNION_TYPE
1229 		      || ctx == TREE_TYPE (TREE_PURPOSE (*last_p))))
1230 	    {
1231 	      /* A mem-initializer hides an NSDMI.  */
1232 	      if (TREE_VALUE (init) && !TREE_VALUE (*last_p))
1233 		*last_p = TREE_CHAIN (*last_p);
1234 	      else if (TREE_VALUE (*last_p) && !TREE_VALUE (init))
1235 		goto splice;
1236 	      else
1237 		{
1238 		  error_at (DECL_SOURCE_LOCATION (current_function_decl),
1239 			    "initializations for multiple members of %qT",
1240 			    ctx);
1241 		  goto splice;
1242 		}
1243 	    }
1244 
1245 	  last_p = p;
1246 
1247 	next:
1248 	  p = &TREE_CHAIN (*p);
1249 	  continue;
1250 	splice:
1251 	  *p = TREE_CHAIN (*p);
1252 	  continue;
1253 	}
1254     }
1255 
1256   return sorted_inits;
1257 }
1258 
1259 /* Callback for cp_walk_tree to mark all PARM_DECLs in a tree as read.  */
1260 
1261 static tree
mark_exp_read_r(tree * tp,int *,void *)1262 mark_exp_read_r (tree *tp, int *, void *)
1263 {
1264   tree t = *tp;
1265   if (TREE_CODE (t) == PARM_DECL)
1266     mark_exp_read (t);
1267   return NULL_TREE;
1268 }
1269 
1270 /* Initialize all bases and members of CURRENT_CLASS_TYPE.  MEM_INITS
1271    is a TREE_LIST giving the explicit mem-initializer-list for the
1272    constructor.  The TREE_PURPOSE of each entry is a subobject (a
1273    FIELD_DECL or a BINFO) of the CURRENT_CLASS_TYPE.  The TREE_VALUE
1274    is a TREE_LIST giving the arguments to the constructor or
1275    void_type_node for an empty list of arguments.  */
1276 
1277 void
emit_mem_initializers(tree mem_inits)1278 emit_mem_initializers (tree mem_inits)
1279 {
1280   int flags = LOOKUP_NORMAL;
1281 
1282   /* We will already have issued an error message about the fact that
1283      the type is incomplete.  */
1284   if (!COMPLETE_TYPE_P (current_class_type))
1285     return;
1286 
1287   if (mem_inits
1288       && TYPE_P (TREE_PURPOSE (mem_inits))
1289       && same_type_p (TREE_PURPOSE (mem_inits), current_class_type))
1290     {
1291       /* Delegating constructor. */
1292       gcc_assert (TREE_CHAIN (mem_inits) == NULL_TREE);
1293       perform_target_ctor (TREE_VALUE (mem_inits));
1294       return;
1295     }
1296 
1297   if (DECL_DEFAULTED_FN (current_function_decl)
1298       && ! DECL_INHERITED_CTOR (current_function_decl))
1299     flags |= LOOKUP_DEFAULTED;
1300 
1301   /* Sort the mem-initializers into the order in which the
1302      initializations should be performed.  */
1303   mem_inits = sort_mem_initializers (current_class_type, mem_inits);
1304 
1305   in_base_initializer = 1;
1306 
1307   /* Initialize base classes.  */
1308   for (; (mem_inits
1309 	  && TREE_CODE (TREE_PURPOSE (mem_inits)) != FIELD_DECL);
1310        mem_inits = TREE_CHAIN (mem_inits))
1311     {
1312       tree subobject = TREE_PURPOSE (mem_inits);
1313       tree arguments = TREE_VALUE (mem_inits);
1314 
1315       /* We already have issued an error message.  */
1316       if (arguments == error_mark_node)
1317 	continue;
1318 
1319       /* Suppress access control when calling the inherited ctor.  */
1320       bool inherited_base = (DECL_INHERITED_CTOR (current_function_decl)
1321 			     && flag_new_inheriting_ctors
1322 			     && arguments);
1323       if (inherited_base)
1324 	push_deferring_access_checks (dk_deferred);
1325 
1326       if (arguments == NULL_TREE)
1327 	{
1328 	  /* If these initializations are taking place in a copy constructor,
1329 	     the base class should probably be explicitly initialized if there
1330 	     is a user-defined constructor in the base class (other than the
1331 	     default constructor, which will be called anyway).  */
1332 	  if (extra_warnings
1333 	      && DECL_COPY_CONSTRUCTOR_P (current_function_decl)
1334 	      && type_has_user_nondefault_constructor (BINFO_TYPE (subobject)))
1335 	    warning_at (DECL_SOURCE_LOCATION (current_function_decl),
1336 			OPT_Wextra, "base class %q#T should be explicitly "
1337 			"initialized in the copy constructor",
1338 			BINFO_TYPE (subobject));
1339 	}
1340 
1341       /* Initialize the base.  */
1342       if (!BINFO_VIRTUAL_P (subobject))
1343 	{
1344 	  tree base_addr;
1345 
1346 	  base_addr = build_base_path (PLUS_EXPR, current_class_ptr,
1347 				       subobject, 1, tf_warning_or_error);
1348 	  expand_aggr_init_1 (subobject, NULL_TREE,
1349 			      cp_build_fold_indirect_ref (base_addr),
1350 			      arguments,
1351 			      flags,
1352                               tf_warning_or_error);
1353 	  expand_cleanup_for_base (subobject, NULL_TREE);
1354 	}
1355       else if (!ABSTRACT_CLASS_TYPE_P (current_class_type))
1356 	/* C++14 DR1658 Means we do not have to construct vbases of
1357 	   abstract classes.  */
1358 	construct_virtual_base (subobject, arguments);
1359       else
1360 	/* When not constructing vbases of abstract classes, at least mark
1361 	   the arguments expressions as read to avoid
1362 	   -Wunused-but-set-parameter false positives.  */
1363 	cp_walk_tree (&arguments, mark_exp_read_r, NULL, NULL);
1364 
1365       if (inherited_base)
1366 	pop_deferring_access_checks ();
1367     }
1368   in_base_initializer = 0;
1369 
1370   /* Initialize the vptrs.  */
1371   initialize_vtbl_ptrs (current_class_ptr);
1372 
1373   /* Initialize the data members.  */
1374   while (mem_inits)
1375     {
1376       perform_member_init (TREE_PURPOSE (mem_inits),
1377 			   TREE_VALUE (mem_inits));
1378       mem_inits = TREE_CHAIN (mem_inits);
1379     }
1380 }
1381 
1382 /* Returns the address of the vtable (i.e., the value that should be
1383    assigned to the vptr) for BINFO.  */
1384 
1385 tree
build_vtbl_address(tree binfo)1386 build_vtbl_address (tree binfo)
1387 {
1388   tree binfo_for = binfo;
1389   tree vtbl;
1390 
1391   if (BINFO_VPTR_INDEX (binfo) && BINFO_VIRTUAL_P (binfo))
1392     /* If this is a virtual primary base, then the vtable we want to store
1393        is that for the base this is being used as the primary base of.  We
1394        can't simply skip the initialization, because we may be expanding the
1395        inits of a subobject constructor where the virtual base layout
1396        can be different.  */
1397     while (BINFO_PRIMARY_P (binfo_for))
1398       binfo_for = BINFO_INHERITANCE_CHAIN (binfo_for);
1399 
1400   /* Figure out what vtable BINFO's vtable is based on, and mark it as
1401      used.  */
1402   vtbl = get_vtbl_decl_for_binfo (binfo_for);
1403   TREE_USED (vtbl) = true;
1404 
1405   /* Now compute the address to use when initializing the vptr.  */
1406   vtbl = unshare_expr (BINFO_VTABLE (binfo_for));
1407   if (VAR_P (vtbl))
1408     vtbl = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (vtbl)), vtbl);
1409 
1410   return vtbl;
1411 }
1412 
1413 /* This code sets up the virtual function tables appropriate for
1414    the pointer DECL.  It is a one-ply initialization.
1415 
1416    BINFO is the exact type that DECL is supposed to be.  In
1417    multiple inheritance, this might mean "C's A" if C : A, B.  */
1418 
1419 static void
expand_virtual_init(tree binfo,tree decl)1420 expand_virtual_init (tree binfo, tree decl)
1421 {
1422   tree vtbl, vtbl_ptr;
1423   tree vtt_index;
1424 
1425   /* Compute the initializer for vptr.  */
1426   vtbl = build_vtbl_address (binfo);
1427 
1428   /* We may get this vptr from a VTT, if this is a subobject
1429      constructor or subobject destructor.  */
1430   vtt_index = BINFO_VPTR_INDEX (binfo);
1431   if (vtt_index)
1432     {
1433       tree vtbl2;
1434       tree vtt_parm;
1435 
1436       /* Compute the value to use, when there's a VTT.  */
1437       vtt_parm = current_vtt_parm;
1438       vtbl2 = fold_build_pointer_plus (vtt_parm, vtt_index);
1439       vtbl2 = cp_build_fold_indirect_ref (vtbl2);
1440       vtbl2 = convert (TREE_TYPE (vtbl), vtbl2);
1441 
1442       /* The actual initializer is the VTT value only in the subobject
1443 	 constructor.  In maybe_clone_body we'll substitute NULL for
1444 	 the vtt_parm in the case of the non-subobject constructor.  */
1445       vtbl = build_if_in_charge (vtbl, vtbl2);
1446     }
1447 
1448   /* Compute the location of the vtpr.  */
1449   vtbl_ptr = build_vfield_ref (cp_build_fold_indirect_ref (decl),
1450 			       TREE_TYPE (binfo));
1451   gcc_assert (vtbl_ptr != error_mark_node);
1452 
1453   /* Assign the vtable to the vptr.  */
1454   vtbl = convert_force (TREE_TYPE (vtbl_ptr), vtbl, 0, tf_warning_or_error);
1455   finish_expr_stmt (cp_build_modify_expr (input_location, vtbl_ptr, NOP_EXPR,
1456 					  vtbl, tf_warning_or_error));
1457 }
1458 
1459 /* If an exception is thrown in a constructor, those base classes already
1460    constructed must be destroyed.  This function creates the cleanup
1461    for BINFO, which has just been constructed.  If FLAG is non-NULL,
1462    it is a DECL which is nonzero when this base needs to be
1463    destroyed.  */
1464 
1465 static void
expand_cleanup_for_base(tree binfo,tree flag)1466 expand_cleanup_for_base (tree binfo, tree flag)
1467 {
1468   tree expr;
1469 
1470   if (!type_build_dtor_call (BINFO_TYPE (binfo)))
1471     return;
1472 
1473   /* Call the destructor.  */
1474   expr = build_special_member_call (current_class_ref,
1475 				    base_dtor_identifier,
1476 				    NULL,
1477 				    binfo,
1478 				    LOOKUP_NORMAL | LOOKUP_NONVIRTUAL,
1479                                     tf_warning_or_error);
1480 
1481   if (TYPE_HAS_TRIVIAL_DESTRUCTOR (BINFO_TYPE (binfo)))
1482     return;
1483 
1484   if (flag)
1485     expr = fold_build3_loc (input_location,
1486 			COND_EXPR, void_type_node,
1487 			c_common_truthvalue_conversion (input_location, flag),
1488 			expr, integer_zero_node);
1489 
1490   finish_eh_cleanup (expr);
1491 }
1492 
1493 /* Construct the virtual base-class VBASE passing the ARGUMENTS to its
1494    constructor.  */
1495 
1496 static void
construct_virtual_base(tree vbase,tree arguments)1497 construct_virtual_base (tree vbase, tree arguments)
1498 {
1499   tree inner_if_stmt;
1500   tree exp;
1501   tree flag;
1502 
1503   /* If there are virtual base classes with destructors, we need to
1504      emit cleanups to destroy them if an exception is thrown during
1505      the construction process.  These exception regions (i.e., the
1506      period during which the cleanups must occur) begin from the time
1507      the construction is complete to the end of the function.  If we
1508      create a conditional block in which to initialize the
1509      base-classes, then the cleanup region for the virtual base begins
1510      inside a block, and ends outside of that block.  This situation
1511      confuses the sjlj exception-handling code.  Therefore, we do not
1512      create a single conditional block, but one for each
1513      initialization.  (That way the cleanup regions always begin
1514      in the outer block.)  We trust the back end to figure out
1515      that the FLAG will not change across initializations, and
1516      avoid doing multiple tests.  */
1517   flag = DECL_CHAIN (DECL_ARGUMENTS (current_function_decl));
1518   inner_if_stmt = begin_if_stmt ();
1519   finish_if_stmt_cond (flag, inner_if_stmt);
1520 
1521   /* Compute the location of the virtual base.  If we're
1522      constructing virtual bases, then we must be the most derived
1523      class.  Therefore, we don't have to look up the virtual base;
1524      we already know where it is.  */
1525   exp = convert_to_base_statically (current_class_ref, vbase);
1526 
1527   expand_aggr_init_1 (vbase, current_class_ref, exp, arguments,
1528 		      0, tf_warning_or_error);
1529   finish_then_clause (inner_if_stmt);
1530   finish_if_stmt (inner_if_stmt);
1531 
1532   expand_cleanup_for_base (vbase, flag);
1533 }
1534 
1535 /* Find the context in which this FIELD can be initialized.  */
1536 
1537 static tree
initializing_context(tree field)1538 initializing_context (tree field)
1539 {
1540   tree t = DECL_CONTEXT (field);
1541 
1542   /* Anonymous union members can be initialized in the first enclosing
1543      non-anonymous union context.  */
1544   while (t && ANON_AGGR_TYPE_P (t))
1545     t = TYPE_CONTEXT (t);
1546   return t;
1547 }
1548 
1549 /* Function to give error message if member initialization specification
1550    is erroneous.  FIELD is the member we decided to initialize.
1551    TYPE is the type for which the initialization is being performed.
1552    FIELD must be a member of TYPE.
1553 
1554    MEMBER_NAME is the name of the member.  */
1555 
1556 static int
member_init_ok_or_else(tree field,tree type,tree member_name)1557 member_init_ok_or_else (tree field, tree type, tree member_name)
1558 {
1559   if (field == error_mark_node)
1560     return 0;
1561   if (!field)
1562     {
1563       error ("class %qT does not have any field named %qD", type,
1564 	     member_name);
1565       return 0;
1566     }
1567   if (VAR_P (field))
1568     {
1569       error ("%q#D is a static data member; it can only be "
1570 	     "initialized at its definition",
1571 	     field);
1572       return 0;
1573     }
1574   if (TREE_CODE (field) != FIELD_DECL)
1575     {
1576       error ("%q#D is not a non-static data member of %qT",
1577 	     field, type);
1578       return 0;
1579     }
1580   if (initializing_context (field) != type)
1581     {
1582       error ("class %qT does not have any field named %qD", type,
1583 		member_name);
1584       return 0;
1585     }
1586 
1587   return 1;
1588 }
1589 
1590 /* NAME is a FIELD_DECL, an IDENTIFIER_NODE which names a field, or it
1591    is a _TYPE node or TYPE_DECL which names a base for that type.
1592    Check the validity of NAME, and return either the base _TYPE, base
1593    binfo, or the FIELD_DECL of the member.  If NAME is invalid, return
1594    NULL_TREE and issue a diagnostic.
1595 
1596    An old style unnamed direct single base construction is permitted,
1597    where NAME is NULL.  */
1598 
1599 tree
expand_member_init(tree name)1600 expand_member_init (tree name)
1601 {
1602   tree basetype;
1603   tree field;
1604 
1605   if (!current_class_ref)
1606     return NULL_TREE;
1607 
1608   if (!name)
1609     {
1610       /* This is an obsolete unnamed base class initializer.  The
1611 	 parser will already have warned about its use.  */
1612       switch (BINFO_N_BASE_BINFOS (TYPE_BINFO (current_class_type)))
1613 	{
1614 	case 0:
1615 	  error ("unnamed initializer for %qT, which has no base classes",
1616 		 current_class_type);
1617 	  return NULL_TREE;
1618 	case 1:
1619 	  basetype = BINFO_TYPE
1620 	    (BINFO_BASE_BINFO (TYPE_BINFO (current_class_type), 0));
1621 	  break;
1622 	default:
1623 	  error ("unnamed initializer for %qT, which uses multiple inheritance",
1624 		 current_class_type);
1625 	  return NULL_TREE;
1626       }
1627     }
1628   else if (TYPE_P (name))
1629     {
1630       basetype = TYPE_MAIN_VARIANT (name);
1631       name = TYPE_NAME (name);
1632     }
1633   else if (TREE_CODE (name) == TYPE_DECL)
1634     basetype = TYPE_MAIN_VARIANT (TREE_TYPE (name));
1635   else
1636     basetype = NULL_TREE;
1637 
1638   if (basetype)
1639     {
1640       tree class_binfo;
1641       tree direct_binfo;
1642       tree virtual_binfo;
1643       int i;
1644 
1645       if (current_template_parms
1646 	  || same_type_p (basetype, current_class_type))
1647 	  return basetype;
1648 
1649       class_binfo = TYPE_BINFO (current_class_type);
1650       direct_binfo = NULL_TREE;
1651       virtual_binfo = NULL_TREE;
1652 
1653       /* Look for a direct base.  */
1654       for (i = 0; BINFO_BASE_ITERATE (class_binfo, i, direct_binfo); ++i)
1655 	if (SAME_BINFO_TYPE_P (BINFO_TYPE (direct_binfo), basetype))
1656 	  break;
1657 
1658       /* Look for a virtual base -- unless the direct base is itself
1659 	 virtual.  */
1660       if (!direct_binfo || !BINFO_VIRTUAL_P (direct_binfo))
1661 	virtual_binfo = binfo_for_vbase (basetype, current_class_type);
1662 
1663       /* [class.base.init]
1664 
1665 	 If a mem-initializer-id is ambiguous because it designates
1666 	 both a direct non-virtual base class and an inherited virtual
1667 	 base class, the mem-initializer is ill-formed.  */
1668       if (direct_binfo && virtual_binfo)
1669 	{
1670 	  error ("%qD is both a direct base and an indirect virtual base",
1671 		 basetype);
1672 	  return NULL_TREE;
1673 	}
1674 
1675       if (!direct_binfo && !virtual_binfo)
1676 	{
1677 	  if (CLASSTYPE_VBASECLASSES (current_class_type))
1678 	    error ("type %qT is not a direct or virtual base of %qT",
1679 		   basetype, current_class_type);
1680 	  else
1681 	    error ("type %qT is not a direct base of %qT",
1682 		   basetype, current_class_type);
1683 	  return NULL_TREE;
1684 	}
1685 
1686       return direct_binfo ? direct_binfo : virtual_binfo;
1687     }
1688   else
1689     {
1690       if (identifier_p (name))
1691 	field = lookup_field (current_class_type, name, 1, false);
1692       else
1693 	field = name;
1694 
1695       if (member_init_ok_or_else (field, current_class_type, name))
1696 	return field;
1697     }
1698 
1699   return NULL_TREE;
1700 }
1701 
1702 /* This is like `expand_member_init', only it stores one aggregate
1703    value into another.
1704 
1705    INIT comes in two flavors: it is either a value which
1706    is to be stored in EXP, or it is a parameter list
1707    to go to a constructor, which will operate on EXP.
1708    If INIT is not a parameter list for a constructor, then set
1709    LOOKUP_ONLYCONVERTING.
1710    If FLAGS is LOOKUP_ONLYCONVERTING then it is the = init form of
1711    the initializer, if FLAGS is 0, then it is the (init) form.
1712    If `init' is a CONSTRUCTOR, then we emit a warning message,
1713    explaining that such initializations are invalid.
1714 
1715    If INIT resolves to a CALL_EXPR which happens to return
1716    something of the type we are looking for, then we know
1717    that we can safely use that call to perform the
1718    initialization.
1719 
1720    The virtual function table pointer cannot be set up here, because
1721    we do not really know its type.
1722 
1723    This never calls operator=().
1724 
1725    When initializing, nothing is CONST.
1726 
1727    A default copy constructor may have to be used to perform the
1728    initialization.
1729 
1730    A constructor or a conversion operator may have to be used to
1731    perform the initialization, but not both, as it would be ambiguous.  */
1732 
1733 tree
build_aggr_init(tree exp,tree init,int flags,tsubst_flags_t complain)1734 build_aggr_init (tree exp, tree init, int flags, tsubst_flags_t complain)
1735 {
1736   tree stmt_expr;
1737   tree compound_stmt;
1738   int destroy_temps;
1739   tree type = TREE_TYPE (exp);
1740   int was_const = TREE_READONLY (exp);
1741   int was_volatile = TREE_THIS_VOLATILE (exp);
1742   int is_global;
1743 
1744   if (init == error_mark_node)
1745     return error_mark_node;
1746 
1747   location_t init_loc = (init
1748 			 ? cp_expr_loc_or_input_loc (init)
1749 			 : location_of (exp));
1750 
1751   TREE_READONLY (exp) = 0;
1752   TREE_THIS_VOLATILE (exp) = 0;
1753 
1754   if (TREE_CODE (type) == ARRAY_TYPE)
1755     {
1756       tree itype = init ? TREE_TYPE (init) : NULL_TREE;
1757       int from_array = 0;
1758 
1759       if (VAR_P (exp) && DECL_DECOMPOSITION_P (exp))
1760 	{
1761 	  from_array = 1;
1762 	  init = mark_rvalue_use (init);
1763 	  if (init
1764 	      && DECL_P (tree_strip_any_location_wrapper (init))
1765 	      && !(flags & LOOKUP_ONLYCONVERTING))
1766 	    {
1767 	      /* Wrap the initializer in a CONSTRUCTOR so that build_vec_init
1768 		 recognizes it as direct-initialization.  */
1769 	      init = build_constructor_single (init_list_type_node,
1770 					       NULL_TREE, init);
1771 	      CONSTRUCTOR_IS_DIRECT_INIT (init) = true;
1772 	    }
1773 	}
1774       else
1775 	{
1776 	  /* Must arrange to initialize each element of EXP
1777 	     from elements of INIT.  */
1778 	  if (cv_qualified_p (type))
1779 	    TREE_TYPE (exp) = cv_unqualified (type);
1780 	  if (itype && cv_qualified_p (itype))
1781 	    TREE_TYPE (init) = cv_unqualified (itype);
1782 	  from_array = (itype && same_type_p (TREE_TYPE (init),
1783 					      TREE_TYPE (exp)));
1784 
1785 	  if (init && !BRACE_ENCLOSED_INITIALIZER_P (init)
1786 	      && (!from_array
1787 		  || (TREE_CODE (init) != CONSTRUCTOR
1788 		      /* Can happen, eg, handling the compound-literals
1789 			 extension (ext/complit12.C).  */
1790 		      && TREE_CODE (init) != TARGET_EXPR)))
1791 	    {
1792 	      if (complain & tf_error)
1793 		error_at (init_loc, "array must be initialized "
1794 			  "with a brace-enclosed initializer");
1795 	      return error_mark_node;
1796 	    }
1797 	}
1798 
1799       stmt_expr = build_vec_init (exp, NULL_TREE, init,
1800 				  /*explicit_value_init_p=*/false,
1801 				  from_array,
1802                                   complain);
1803       TREE_READONLY (exp) = was_const;
1804       TREE_THIS_VOLATILE (exp) = was_volatile;
1805       TREE_TYPE (exp) = type;
1806       /* Restore the type of init unless it was used directly.  */
1807       if (init && TREE_CODE (stmt_expr) != INIT_EXPR)
1808 	TREE_TYPE (init) = itype;
1809       return stmt_expr;
1810     }
1811 
1812   if (init && init != void_type_node
1813       && TREE_CODE (init) != TREE_LIST
1814       && !(TREE_CODE (init) == TARGET_EXPR
1815 	   && TARGET_EXPR_DIRECT_INIT_P (init))
1816       && !DIRECT_LIST_INIT_P (init))
1817     flags |= LOOKUP_ONLYCONVERTING;
1818 
1819   is_global = begin_init_stmts (&stmt_expr, &compound_stmt);
1820   destroy_temps = stmts_are_full_exprs_p ();
1821   current_stmt_tree ()->stmts_are_full_exprs_p = 0;
1822   expand_aggr_init_1 (TYPE_BINFO (type), exp, exp,
1823 		      init, LOOKUP_NORMAL|flags, complain);
1824   stmt_expr = finish_init_stmts (is_global, stmt_expr, compound_stmt);
1825   current_stmt_tree ()->stmts_are_full_exprs_p = destroy_temps;
1826   TREE_READONLY (exp) = was_const;
1827   TREE_THIS_VOLATILE (exp) = was_volatile;
1828 
1829   if ((VAR_P (exp) || TREE_CODE (exp) == PARM_DECL)
1830       && TREE_SIDE_EFFECTS (stmt_expr)
1831       && !lookup_attribute ("warn_unused", TYPE_ATTRIBUTES (type)))
1832     /* Just know that we've seen something for this node.  */
1833     TREE_USED (exp) = 1;
1834 
1835   return stmt_expr;
1836 }
1837 
1838 static void
expand_default_init(tree binfo,tree true_exp,tree exp,tree init,int flags,tsubst_flags_t complain)1839 expand_default_init (tree binfo, tree true_exp, tree exp, tree init, int flags,
1840                      tsubst_flags_t complain)
1841 {
1842   tree type = TREE_TYPE (exp);
1843 
1844   /* It fails because there may not be a constructor which takes
1845      its own type as the first (or only parameter), but which does
1846      take other types via a conversion.  So, if the thing initializing
1847      the expression is a unit element of type X, first try X(X&),
1848      followed by initialization by X.  If neither of these work
1849      out, then look hard.  */
1850   tree rval;
1851   vec<tree, va_gc> *parms;
1852 
1853   /* If we have direct-initialization from an initializer list, pull
1854      it out of the TREE_LIST so the code below can see it.  */
1855   if (init && TREE_CODE (init) == TREE_LIST
1856       && DIRECT_LIST_INIT_P (TREE_VALUE (init)))
1857     {
1858       gcc_checking_assert ((flags & LOOKUP_ONLYCONVERTING) == 0
1859 			   && TREE_CHAIN (init) == NULL_TREE);
1860       init = TREE_VALUE (init);
1861       /* Only call reshape_init if it has not been called earlier
1862 	 by the callers.  */
1863       if (BRACE_ENCLOSED_INITIALIZER_P (init) && CP_AGGREGATE_TYPE_P (type))
1864 	init = reshape_init (type, init, complain);
1865     }
1866 
1867   if (init && BRACE_ENCLOSED_INITIALIZER_P (init)
1868       && CP_AGGREGATE_TYPE_P (type))
1869     /* A brace-enclosed initializer for an aggregate.  In C++0x this can
1870        happen for direct-initialization, too.  */
1871     init = digest_init (type, init, complain);
1872 
1873   /* A CONSTRUCTOR of the target's type is a previously digested
1874      initializer, whether that happened just above or in
1875      cp_parser_late_parsing_nsdmi.
1876 
1877      A TARGET_EXPR with TARGET_EXPR_DIRECT_INIT_P or TARGET_EXPR_LIST_INIT_P
1878      set represents the whole initialization, so we shouldn't build up
1879      another ctor call.  */
1880   if (init
1881       && (TREE_CODE (init) == CONSTRUCTOR
1882 	  || (TREE_CODE (init) == TARGET_EXPR
1883 	      && (TARGET_EXPR_DIRECT_INIT_P (init)
1884 		  || TARGET_EXPR_LIST_INIT_P (init))))
1885       && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (init), type))
1886     {
1887       /* Early initialization via a TARGET_EXPR only works for
1888 	 complete objects.  */
1889       gcc_assert (TREE_CODE (init) == CONSTRUCTOR || true_exp == exp);
1890 
1891       init = build2 (INIT_EXPR, TREE_TYPE (exp), exp, init);
1892       TREE_SIDE_EFFECTS (init) = 1;
1893       finish_expr_stmt (init);
1894       return;
1895     }
1896 
1897   if (init && TREE_CODE (init) != TREE_LIST
1898       && (flags & LOOKUP_ONLYCONVERTING)
1899       && !unsafe_return_slot_p (exp))
1900     {
1901       /* Base subobjects should only get direct-initialization.  */
1902       gcc_assert (true_exp == exp);
1903 
1904       if (flags & DIRECT_BIND)
1905 	/* Do nothing.  We hit this in two cases:  Reference initialization,
1906 	   where we aren't initializing a real variable, so we don't want
1907 	   to run a new constructor; and catching an exception, where we
1908 	   have already built up the constructor call so we could wrap it
1909 	   in an exception region.  */;
1910       else
1911 	init = ocp_convert (type, init, CONV_IMPLICIT|CONV_FORCE_TEMP,
1912 			    flags, complain);
1913 
1914       if (TREE_CODE (init) == MUST_NOT_THROW_EXPR)
1915 	/* We need to protect the initialization of a catch parm with a
1916 	   call to terminate(), which shows up as a MUST_NOT_THROW_EXPR
1917 	   around the TARGET_EXPR for the copy constructor.  See
1918 	   initialize_handler_parm.  */
1919 	{
1920 	  TREE_OPERAND (init, 0) = build2 (INIT_EXPR, TREE_TYPE (exp), exp,
1921 					   TREE_OPERAND (init, 0));
1922 	  TREE_TYPE (init) = void_type_node;
1923 	}
1924       else
1925 	init = build2 (INIT_EXPR, TREE_TYPE (exp), exp, init);
1926       TREE_SIDE_EFFECTS (init) = 1;
1927       finish_expr_stmt (init);
1928       return;
1929     }
1930 
1931   if (init == NULL_TREE)
1932     parms = NULL;
1933   else if (TREE_CODE (init) == TREE_LIST && !TREE_TYPE (init))
1934     {
1935       parms = make_tree_vector ();
1936       for (; init != NULL_TREE; init = TREE_CHAIN (init))
1937 	vec_safe_push (parms, TREE_VALUE (init));
1938     }
1939   else
1940     parms = make_tree_vector_single (init);
1941 
1942   if (exp == current_class_ref && current_function_decl
1943       && DECL_HAS_IN_CHARGE_PARM_P (current_function_decl))
1944     {
1945       /* Delegating constructor. */
1946       tree complete;
1947       tree base;
1948       tree elt; unsigned i;
1949 
1950       /* Unshare the arguments for the second call.  */
1951       releasing_vec parms2;
1952       FOR_EACH_VEC_SAFE_ELT (parms, i, elt)
1953 	{
1954 	  elt = break_out_target_exprs (elt);
1955 	  vec_safe_push (parms2, elt);
1956 	}
1957       complete = build_special_member_call (exp, complete_ctor_identifier,
1958 					    &parms2, binfo, flags,
1959 					    complain);
1960       complete = fold_build_cleanup_point_expr (void_type_node, complete);
1961 
1962       base = build_special_member_call (exp, base_ctor_identifier,
1963 					&parms, binfo, flags,
1964 					complain);
1965       base = fold_build_cleanup_point_expr (void_type_node, base);
1966       rval = build_if_in_charge (complete, base);
1967     }
1968    else
1969     {
1970       tree ctor_name = (true_exp == exp
1971 			? complete_ctor_identifier : base_ctor_identifier);
1972 
1973       rval = build_special_member_call (exp, ctor_name, &parms, binfo, flags,
1974 					complain);
1975     }
1976 
1977   if (parms != NULL)
1978     release_tree_vector (parms);
1979 
1980   if (exp == true_exp && TREE_CODE (rval) == CALL_EXPR)
1981     {
1982       tree fn = get_callee_fndecl (rval);
1983       if (fn && DECL_DECLARED_CONSTEXPR_P (fn))
1984 	{
1985 	  tree e = maybe_constant_init (rval, exp);
1986 	  if (TREE_CONSTANT (e))
1987 	    rval = build2 (INIT_EXPR, type, exp, e);
1988 	}
1989     }
1990 
1991   /* FIXME put back convert_to_void?  */
1992   if (TREE_SIDE_EFFECTS (rval))
1993     finish_expr_stmt (rval);
1994 }
1995 
1996 /* This function is responsible for initializing EXP with INIT
1997    (if any).
1998 
1999    BINFO is the binfo of the type for who we are performing the
2000    initialization.  For example, if W is a virtual base class of A and B,
2001    and C : A, B.
2002    If we are initializing B, then W must contain B's W vtable, whereas
2003    were we initializing C, W must contain C's W vtable.
2004 
2005    TRUE_EXP is nonzero if it is the true expression being initialized.
2006    In this case, it may be EXP, or may just contain EXP.  The reason we
2007    need this is because if EXP is a base element of TRUE_EXP, we
2008    don't necessarily know by looking at EXP where its virtual
2009    baseclass fields should really be pointing.  But we do know
2010    from TRUE_EXP.  In constructors, we don't know anything about
2011    the value being initialized.
2012 
2013    FLAGS is just passed to `build_new_method_call'.  See that function
2014    for its description.  */
2015 
2016 static void
expand_aggr_init_1(tree binfo,tree true_exp,tree exp,tree init,int flags,tsubst_flags_t complain)2017 expand_aggr_init_1 (tree binfo, tree true_exp, tree exp, tree init, int flags,
2018                     tsubst_flags_t complain)
2019 {
2020   tree type = TREE_TYPE (exp);
2021 
2022   gcc_assert (init != error_mark_node && type != error_mark_node);
2023   gcc_assert (building_stmt_list_p ());
2024 
2025   /* Use a function returning the desired type to initialize EXP for us.
2026      If the function is a constructor, and its first argument is
2027      NULL_TREE, know that it was meant for us--just slide exp on
2028      in and expand the constructor.  Constructors now come
2029      as TARGET_EXPRs.  */
2030 
2031   if (init && VAR_P (exp)
2032       && COMPOUND_LITERAL_P (init))
2033     {
2034       vec<tree, va_gc> *cleanups = NULL;
2035       /* If store_init_value returns NULL_TREE, the INIT has been
2036 	 recorded as the DECL_INITIAL for EXP.  That means there's
2037 	 nothing more we have to do.  */
2038       init = store_init_value (exp, init, &cleanups, flags);
2039       if (init)
2040 	finish_expr_stmt (init);
2041       gcc_assert (!cleanups);
2042       return;
2043     }
2044 
2045   /* List-initialization from {} becomes value-initialization for non-aggregate
2046      classes with default constructors.  Handle this here when we're
2047      initializing a base, so protected access works.  */
2048   if (exp != true_exp && init && TREE_CODE (init) == TREE_LIST)
2049     {
2050       tree elt = TREE_VALUE (init);
2051       if (DIRECT_LIST_INIT_P (elt)
2052 	  && CONSTRUCTOR_ELTS (elt) == 0
2053 	  && CLASSTYPE_NON_AGGREGATE (type)
2054 	  && TYPE_HAS_DEFAULT_CONSTRUCTOR (type))
2055 	init = void_type_node;
2056     }
2057 
2058   /* If an explicit -- but empty -- initializer list was present,
2059      that's value-initialization.  */
2060   if (init == void_type_node)
2061     {
2062       /* If the type has data but no user-provided ctor, we need to zero
2063 	 out the object.  */
2064       if (!type_has_user_provided_constructor (type)
2065 	  && !is_really_empty_class (type, /*ignore_vptr*/true))
2066 	{
2067 	  tree field_size = NULL_TREE;
2068 	  if (exp != true_exp && CLASSTYPE_AS_BASE (type) != type)
2069 	    /* Don't clobber already initialized virtual bases.  */
2070 	    field_size = TYPE_SIZE (CLASSTYPE_AS_BASE (type));
2071 	  init = build_zero_init_1 (type, NULL_TREE, /*static_storage_p=*/false,
2072 				    field_size);
2073 	  init = build2 (INIT_EXPR, type, exp, init);
2074 	  finish_expr_stmt (init);
2075 	}
2076 
2077       /* If we don't need to mess with the constructor at all,
2078 	 then we're done.  */
2079       if (! type_build_ctor_call (type))
2080 	return;
2081 
2082       /* Otherwise fall through and call the constructor.  */
2083       init = NULL_TREE;
2084     }
2085 
2086   /* We know that expand_default_init can handle everything we want
2087      at this point.  */
2088   expand_default_init (binfo, true_exp, exp, init, flags, complain);
2089 }
2090 
2091 /* Report an error if TYPE is not a user-defined, class type.  If
2092    OR_ELSE is nonzero, give an error message.  */
2093 
2094 int
is_class_type(tree type,int or_else)2095 is_class_type (tree type, int or_else)
2096 {
2097   if (type == error_mark_node)
2098     return 0;
2099 
2100   if (! CLASS_TYPE_P (type))
2101     {
2102       if (or_else)
2103 	error ("%qT is not a class type", type);
2104       return 0;
2105     }
2106   return 1;
2107 }
2108 
2109 tree
get_type_value(tree name)2110 get_type_value (tree name)
2111 {
2112   if (name == error_mark_node)
2113     return NULL_TREE;
2114 
2115   if (IDENTIFIER_HAS_TYPE_VALUE (name))
2116     return IDENTIFIER_TYPE_VALUE (name);
2117   else
2118     return NULL_TREE;
2119 }
2120 
2121 /* Build a reference to a member of an aggregate.  This is not a C++
2122    `&', but really something which can have its address taken, and
2123    then act as a pointer to member, for example TYPE :: FIELD can have
2124    its address taken by saying & TYPE :: FIELD.  ADDRESS_P is true if
2125    this expression is the operand of "&".
2126 
2127    @@ Prints out lousy diagnostics for operator <typename>
2128    @@ fields.
2129 
2130    @@ This function should be rewritten and placed in search.c.  */
2131 
2132 tree
build_offset_ref(tree type,tree member,bool address_p,tsubst_flags_t complain)2133 build_offset_ref (tree type, tree member, bool address_p,
2134 		  tsubst_flags_t complain)
2135 {
2136   tree decl;
2137   tree basebinfo = NULL_TREE;
2138 
2139   /* class templates can come in as TEMPLATE_DECLs here.  */
2140   if (TREE_CODE (member) == TEMPLATE_DECL)
2141     return member;
2142 
2143   if (dependent_scope_p (type) || type_dependent_expression_p (member))
2144     return build_qualified_name (NULL_TREE, type, member,
2145 				  /*template_p=*/false);
2146 
2147   gcc_assert (TYPE_P (type));
2148   if (! is_class_type (type, 1))
2149     return error_mark_node;
2150 
2151   gcc_assert (DECL_P (member) || BASELINK_P (member));
2152   /* Callers should call mark_used before this point.  */
2153   gcc_assert (!DECL_P (member) || TREE_USED (member));
2154 
2155   type = TYPE_MAIN_VARIANT (type);
2156   if (!COMPLETE_OR_OPEN_TYPE_P (complete_type (type)))
2157     {
2158       if (complain & tf_error)
2159 	error ("incomplete type %qT does not have member %qD", type, member);
2160       return error_mark_node;
2161     }
2162 
2163   /* Entities other than non-static members need no further
2164      processing.  */
2165   if (TREE_CODE (member) == TYPE_DECL)
2166     return member;
2167   if (VAR_P (member) || TREE_CODE (member) == CONST_DECL)
2168     return convert_from_reference (member);
2169 
2170   if (TREE_CODE (member) == FIELD_DECL && DECL_C_BIT_FIELD (member))
2171     {
2172       if (complain & tf_error)
2173 	error ("invalid pointer to bit-field %qD", member);
2174       return error_mark_node;
2175     }
2176 
2177   /* Set up BASEBINFO for member lookup.  */
2178   decl = maybe_dummy_object (type, &basebinfo);
2179 
2180   /* A lot of this logic is now handled in lookup_member.  */
2181   if (BASELINK_P (member))
2182     {
2183       /* Go from the TREE_BASELINK to the member function info.  */
2184       tree t = BASELINK_FUNCTIONS (member);
2185 
2186       if (TREE_CODE (t) != TEMPLATE_ID_EXPR && !really_overloaded_fn (t))
2187 	{
2188 	  /* Get rid of a potential OVERLOAD around it.  */
2189 	  t = OVL_FIRST (t);
2190 
2191 	  /* Unique functions are handled easily.  */
2192 
2193 	  /* For non-static member of base class, we need a special rule
2194 	     for access checking [class.protected]:
2195 
2196 	       If the access is to form a pointer to member, the
2197 	       nested-name-specifier shall name the derived class
2198 	       (or any class derived from that class).  */
2199 	  bool ok;
2200 	  if (address_p && DECL_P (t)
2201 	      && DECL_NONSTATIC_MEMBER_P (t))
2202 	    ok = perform_or_defer_access_check (TYPE_BINFO (type), t, t,
2203 						complain);
2204 	  else
2205 	    ok = perform_or_defer_access_check (basebinfo, t, t,
2206 						complain);
2207 	  if (!ok)
2208 	    return error_mark_node;
2209 	  if (DECL_STATIC_FUNCTION_P (t))
2210 	    return t;
2211 	  member = t;
2212 	}
2213       else
2214 	TREE_TYPE (member) = unknown_type_node;
2215     }
2216   else if (address_p && TREE_CODE (member) == FIELD_DECL)
2217     {
2218       /* We need additional test besides the one in
2219 	 check_accessibility_of_qualified_id in case it is
2220 	 a pointer to non-static member.  */
2221       if (!perform_or_defer_access_check (TYPE_BINFO (type), member, member,
2222 					  complain))
2223 	return error_mark_node;
2224     }
2225 
2226   if (!address_p)
2227     {
2228       /* If MEMBER is non-static, then the program has fallen afoul of
2229 	 [expr.prim]:
2230 
2231 	   An id-expression that denotes a nonstatic data member or
2232 	   nonstatic member function of a class can only be used:
2233 
2234 	   -- as part of a class member access (_expr.ref_) in which the
2235 	   object-expression refers to the member's class or a class
2236 	   derived from that class, or
2237 
2238 	   -- to form a pointer to member (_expr.unary.op_), or
2239 
2240 	   -- in the body of a nonstatic member function of that class or
2241 	   of a class derived from that class (_class.mfct.nonstatic_), or
2242 
2243 	   -- in a mem-initializer for a constructor for that class or for
2244 	   a class derived from that class (_class.base.init_).  */
2245       if (DECL_NONSTATIC_MEMBER_FUNCTION_P (member))
2246 	{
2247 	  /* Build a representation of the qualified name suitable
2248 	     for use as the operand to "&" -- even though the "&" is
2249 	     not actually present.  */
2250 	  member = build2 (OFFSET_REF, TREE_TYPE (member), decl, member);
2251 	  /* In Microsoft mode, treat a non-static member function as if
2252 	     it were a pointer-to-member.  */
2253 	  if (flag_ms_extensions)
2254 	    {
2255 	      PTRMEM_OK_P (member) = 1;
2256 	      return cp_build_addr_expr (member, complain);
2257 	    }
2258 	  if (complain & tf_error)
2259 	    error ("invalid use of non-static member function %qD",
2260 		   TREE_OPERAND (member, 1));
2261 	  return error_mark_node;
2262 	}
2263       else if (TREE_CODE (member) == FIELD_DECL)
2264 	{
2265 	  if (complain & tf_error)
2266 	    error ("invalid use of non-static data member %qD", member);
2267 	  return error_mark_node;
2268 	}
2269       return member;
2270     }
2271 
2272   member = build2 (OFFSET_REF, TREE_TYPE (member), decl, member);
2273   PTRMEM_OK_P (member) = 1;
2274   return member;
2275 }
2276 
2277 /* If DECL is a scalar enumeration constant or variable with a
2278    constant initializer, return the initializer (or, its initializers,
2279    recursively); otherwise, return DECL.  If STRICT_P, the
2280    initializer is only returned if DECL is a
2281    constant-expression.  If RETURN_AGGREGATE_CST_OK_P, it is ok to
2282    return an aggregate constant.  If UNSHARE_P, return an unshared
2283    copy of the initializer.  */
2284 
2285 static tree
constant_value_1(tree decl,bool strict_p,bool return_aggregate_cst_ok_p,bool unshare_p)2286 constant_value_1 (tree decl, bool strict_p, bool return_aggregate_cst_ok_p,
2287 		  bool unshare_p)
2288 {
2289   while (TREE_CODE (decl) == CONST_DECL
2290 	 || decl_constant_var_p (decl)
2291 	 || (!strict_p && VAR_P (decl)
2292 	     && CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (decl))))
2293     {
2294       tree init;
2295       /* If DECL is a static data member in a template
2296 	 specialization, we must instantiate it here.  The
2297 	 initializer for the static data member is not processed
2298 	 until needed; we need it now.  */
2299       mark_used (decl, tf_none);
2300       init = DECL_INITIAL (decl);
2301       if (init == error_mark_node)
2302 	{
2303 	  if (TREE_CODE (decl) == CONST_DECL
2304 	      || DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
2305 	    /* Treat the error as a constant to avoid cascading errors on
2306 	       excessively recursive template instantiation (c++/9335).  */
2307 	    return init;
2308 	  else
2309 	    return decl;
2310 	}
2311       /* Initializers in templates are generally expanded during
2312 	 instantiation, so before that for const int i(2)
2313 	 INIT is a TREE_LIST with the actual initializer as
2314 	 TREE_VALUE.  */
2315       if (processing_template_decl
2316 	  && init
2317 	  && TREE_CODE (init) == TREE_LIST
2318 	  && TREE_CHAIN (init) == NULL_TREE)
2319 	init = TREE_VALUE (init);
2320       /* Instantiate a non-dependent initializer for user variables.  We
2321 	 mustn't do this for the temporary for an array compound literal;
2322 	 trying to instatiate the initializer will keep creating new
2323 	 temporaries until we crash.  Probably it's not useful to do it for
2324 	 other artificial variables, either.  */
2325       if (!DECL_ARTIFICIAL (decl))
2326 	init = instantiate_non_dependent_or_null (init);
2327       if (!init
2328 	  || !TREE_TYPE (init)
2329 	  || !TREE_CONSTANT (init)
2330 	  || (!return_aggregate_cst_ok_p
2331 	      /* Unless RETURN_AGGREGATE_CST_OK_P is true, do not
2332 		 return an aggregate constant (of which string
2333 		 literals are a special case), as we do not want
2334 		 to make inadvertent copies of such entities, and
2335 		 we must be sure that their addresses are the
2336  		 same everywhere.  */
2337 	      && (TREE_CODE (init) == CONSTRUCTOR
2338 		  || TREE_CODE (init) == STRING_CST)))
2339 	break;
2340       /* Don't return a CONSTRUCTOR for a variable with partial run-time
2341 	 initialization, since it doesn't represent the entire value.
2342 	 Similarly for VECTOR_CSTs created by cp_folding those
2343 	 CONSTRUCTORs.  */
2344       if ((TREE_CODE (init) == CONSTRUCTOR
2345 	   || TREE_CODE (init) == VECTOR_CST)
2346 	  && !DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
2347 	break;
2348       /* If the variable has a dynamic initializer, don't use its
2349 	 DECL_INITIAL which doesn't reflect the real value.  */
2350       if (VAR_P (decl)
2351 	  && TREE_STATIC (decl)
2352 	  && !DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)
2353 	  && DECL_NONTRIVIALLY_INITIALIZED_P (decl))
2354 	break;
2355       decl = init;
2356     }
2357   return unshare_p ? unshare_expr (decl) : decl;
2358 }
2359 
2360 /* If DECL is a CONST_DECL, or a constant VAR_DECL initialized by constant
2361    of integral or enumeration type, or a constexpr variable of scalar type,
2362    then return that value.  These are those variables permitted in constant
2363    expressions by [5.19/1].  */
2364 
2365 tree
scalar_constant_value(tree decl)2366 scalar_constant_value (tree decl)
2367 {
2368   return constant_value_1 (decl, /*strict_p=*/true,
2369 			   /*return_aggregate_cst_ok_p=*/false,
2370 			   /*unshare_p=*/true);
2371 }
2372 
2373 /* Like scalar_constant_value, but can also return aggregate initializers.
2374    If UNSHARE_P, return an unshared copy of the initializer.  */
2375 
2376 tree
decl_really_constant_value(tree decl,bool unshare_p)2377 decl_really_constant_value (tree decl, bool unshare_p /*= true*/)
2378 {
2379   return constant_value_1 (decl, /*strict_p=*/true,
2380 			   /*return_aggregate_cst_ok_p=*/true,
2381 			   /*unshare_p=*/unshare_p);
2382 }
2383 
2384 /* A more relaxed version of decl_really_constant_value, used by the
2385    common C/C++ code.  */
2386 
2387 tree
decl_constant_value(tree decl,bool unshare_p)2388 decl_constant_value (tree decl, bool unshare_p)
2389 {
2390   return constant_value_1 (decl, /*strict_p=*/processing_template_decl,
2391 			   /*return_aggregate_cst_ok_p=*/true,
2392 			   /*unshare_p=*/unshare_p);
2393 }
2394 
2395 tree
decl_constant_value(tree decl)2396 decl_constant_value (tree decl)
2397 {
2398   return decl_constant_value (decl, /*unshare_p=*/true);
2399 }
2400 
2401 /* Common subroutines of build_new and build_vec_delete.  */
2402 
2403 /* Build and return a NEW_EXPR.  If NELTS is non-NULL, TYPE[NELTS] is
2404    the type of the object being allocated; otherwise, it's just TYPE.
2405    INIT is the initializer, if any.  USE_GLOBAL_NEW is true if the
2406    user explicitly wrote "::operator new".  PLACEMENT, if non-NULL, is
2407    a vector of arguments to be provided as arguments to a placement
2408    new operator.  This routine performs no semantic checks; it just
2409    creates and returns a NEW_EXPR.  */
2410 
2411 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)2412 build_raw_new_expr (location_t loc, vec<tree, va_gc> *placement, tree type,
2413 		    tree nelts, vec<tree, va_gc> *init, int use_global_new)
2414 {
2415   tree init_list;
2416   tree new_expr;
2417 
2418   /* If INIT is NULL, the we want to store NULL_TREE in the NEW_EXPR.
2419      If INIT is not NULL, then we want to store VOID_ZERO_NODE.  This
2420      permits us to distinguish the case of a missing initializer "new
2421      int" from an empty initializer "new int()".  */
2422   if (init == NULL)
2423     init_list = NULL_TREE;
2424   else if (init->is_empty ())
2425     init_list = void_node;
2426   else
2427     init_list = build_tree_list_vec (init);
2428 
2429   new_expr = build4_loc (loc, NEW_EXPR, build_pointer_type (type),
2430 			 build_tree_list_vec (placement), type, nelts,
2431 			 init_list);
2432   NEW_EXPR_USE_GLOBAL (new_expr) = use_global_new;
2433   TREE_SIDE_EFFECTS (new_expr) = 1;
2434 
2435   return new_expr;
2436 }
2437 
2438 /* Diagnose uninitialized const members or reference members of type
2439    TYPE. USING_NEW is used to disambiguate the diagnostic between a
2440    new expression without a new-initializer and a declaration. Returns
2441    the error count. */
2442 
2443 static int
diagnose_uninitialized_cst_or_ref_member_1(tree type,tree origin,bool using_new,bool complain)2444 diagnose_uninitialized_cst_or_ref_member_1 (tree type, tree origin,
2445 					    bool using_new, bool complain)
2446 {
2447   tree field;
2448   int error_count = 0;
2449 
2450   if (type_has_user_provided_constructor (type))
2451     return 0;
2452 
2453   for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
2454     {
2455       tree field_type;
2456 
2457       if (TREE_CODE (field) != FIELD_DECL)
2458 	continue;
2459 
2460       field_type = strip_array_types (TREE_TYPE (field));
2461 
2462       if (type_has_user_provided_constructor (field_type))
2463 	continue;
2464 
2465       if (TYPE_REF_P (field_type))
2466 	{
2467 	  ++ error_count;
2468 	  if (complain)
2469 	    {
2470 	      if (DECL_CONTEXT (field) == origin)
2471 		{
2472 		  if (using_new)
2473 		    error ("uninitialized reference member in %q#T "
2474 			   "using %<new%> without new-initializer", origin);
2475 		  else
2476 		    error ("uninitialized reference member in %q#T", origin);
2477 		}
2478 	      else
2479 		{
2480 		  if (using_new)
2481 		    error ("uninitialized reference member in base %q#T "
2482 			   "of %q#T using %<new%> without new-initializer",
2483 			   DECL_CONTEXT (field), origin);
2484 		  else
2485 		    error ("uninitialized reference member in base %q#T "
2486 			   "of %q#T", DECL_CONTEXT (field), origin);
2487 		}
2488 	      inform (DECL_SOURCE_LOCATION (field),
2489 		      "%q#D should be initialized", field);
2490 	    }
2491 	}
2492 
2493       if (CP_TYPE_CONST_P (field_type))
2494 	{
2495 	  ++ error_count;
2496 	  if (complain)
2497 	    {
2498 	      if (DECL_CONTEXT (field) == origin)
2499 		{
2500 		  if (using_new)
2501 		    error ("uninitialized const member in %q#T "
2502 			   "using %<new%> without new-initializer", origin);
2503 		  else
2504 		    error ("uninitialized const member in %q#T", origin);
2505 		}
2506 	      else
2507 		{
2508 		  if (using_new)
2509 		    error ("uninitialized const member in base %q#T "
2510 			   "of %q#T using %<new%> without new-initializer",
2511 			   DECL_CONTEXT (field), origin);
2512 		  else
2513 		    error ("uninitialized const member in base %q#T "
2514 			   "of %q#T", DECL_CONTEXT (field), origin);
2515 		}
2516 	      inform (DECL_SOURCE_LOCATION (field),
2517 		      "%q#D should be initialized", field);
2518 	    }
2519 	}
2520 
2521       if (CLASS_TYPE_P (field_type))
2522 	error_count
2523 	  += diagnose_uninitialized_cst_or_ref_member_1 (field_type, origin,
2524 							 using_new, complain);
2525     }
2526   return error_count;
2527 }
2528 
2529 int
diagnose_uninitialized_cst_or_ref_member(tree type,bool using_new,bool complain)2530 diagnose_uninitialized_cst_or_ref_member (tree type, bool using_new, bool complain)
2531 {
2532   return diagnose_uninitialized_cst_or_ref_member_1 (type, type, using_new, complain);
2533 }
2534 
2535 /* Call __cxa_bad_array_new_length to indicate that the size calculation
2536    overflowed.  Pretend it returns sizetype so that it plays nicely in the
2537    COND_EXPR.  */
2538 
2539 tree
throw_bad_array_new_length(void)2540 throw_bad_array_new_length (void)
2541 {
2542   if (!fn)
2543     {
2544       tree name = get_identifier ("__cxa_throw_bad_array_new_length");
2545 
2546       fn = get_global_binding (name);
2547       if (!fn)
2548 	fn = push_throw_library_fn
2549 	  (name, build_function_type_list (sizetype, NULL_TREE));
2550     }
2551 
2552   return build_cxx_call (fn, 0, NULL, tf_warning_or_error);
2553 }
2554 
2555 /* Attempt to find the initializer for flexible array field T in the
2556    initializer INIT, when non-null.  Returns the initializer when
2557    successful and NULL otherwise.  */
2558 static tree
find_flexarray_init(tree t,tree init)2559 find_flexarray_init (tree t, tree init)
2560 {
2561   if (!init || init == error_mark_node)
2562     return NULL_TREE;
2563 
2564   unsigned HOST_WIDE_INT idx;
2565   tree field, elt;
2566 
2567   /* Iterate over all top-level initializer elements.  */
2568   FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init), idx, field, elt)
2569     /* If the member T is found, return it.  */
2570     if (field == t)
2571       return elt;
2572 
2573   return NULL_TREE;
2574 }
2575 
2576 /* Attempt to verify that the argument, OPER, of a placement new expression
2577    refers to an object sufficiently large for an object of TYPE or an array
2578    of NELTS of such objects when NELTS is non-null, and issue a warning when
2579    it does not.  SIZE specifies the size needed to construct the object or
2580    array and captures the result of NELTS * sizeof (TYPE). (SIZE could be
2581    greater when the array under construction requires a cookie to store
2582    NELTS.  GCC's placement new expression stores the cookie when invoking
2583    a user-defined placement new operator function but not the default one.
2584    Placement new expressions with user-defined placement new operator are
2585    not diagnosed since we don't know how they use the buffer (this could
2586    be a future extension).  */
2587 static void
warn_placement_new_too_small(tree type,tree nelts,tree size,tree oper)2588 warn_placement_new_too_small (tree type, tree nelts, tree size, tree oper)
2589 {
2590   location_t loc = cp_expr_loc_or_input_loc (oper);
2591 
2592   /* The number of bytes to add to or subtract from the size of the provided
2593      buffer based on an offset into an array or an array element reference.
2594      Although intermediate results may be negative (as in a[3] - 2) a valid
2595      final result cannot be.  */
2596   offset_int adjust = 0;
2597   /* True when the size of the entire destination object should be used
2598      to compute the possibly optimistic estimate of the available space.  */
2599   bool use_obj_size = false;
2600   /* True when the reference to the destination buffer is an ADDR_EXPR.  */
2601   bool addr_expr = false;
2602 
2603   STRIP_NOPS (oper);
2604 
2605   /* Using a function argument or a (non-array) variable as an argument
2606      to placement new is not checked since it's unknown what it might
2607      point to.  */
2608   if (TREE_CODE (oper) == PARM_DECL
2609       || VAR_P (oper)
2610       || TREE_CODE (oper) == COMPONENT_REF)
2611     return;
2612 
2613   /* Evaluate any constant expressions.  */
2614   size = fold_non_dependent_expr (size);
2615 
2616   /* Handle the common case of array + offset expression when the offset
2617      is a constant.  */
2618   if (TREE_CODE (oper) == POINTER_PLUS_EXPR)
2619     {
2620       /* If the offset is compile-time constant, use it to compute a more
2621 	 accurate estimate of the size of the buffer.  Since the operand
2622 	 of POINTER_PLUS_EXPR is represented as an unsigned type, convert
2623 	 it to signed first.
2624 	 Otherwise, use the size of the entire array as an optimistic
2625 	 estimate (this may lead to false negatives).  */
2626       tree adj = TREE_OPERAND (oper, 1);
2627       adj = fold_for_warn (adj);
2628       if (CONSTANT_CLASS_P (adj))
2629 	adjust += wi::to_offset (convert (ssizetype, adj));
2630       else
2631 	use_obj_size = true;
2632 
2633       oper = TREE_OPERAND (oper, 0);
2634 
2635       STRIP_NOPS (oper);
2636     }
2637 
2638   if (TREE_CODE (oper) == TARGET_EXPR)
2639     oper = TREE_OPERAND (oper, 1);
2640   else if (TREE_CODE (oper) == ADDR_EXPR)
2641     {
2642       addr_expr = true;
2643       oper = TREE_OPERAND (oper, 0);
2644     }
2645 
2646   STRIP_NOPS (oper);
2647 
2648   if (TREE_CODE (oper) == ARRAY_REF
2649       && (addr_expr || TREE_CODE (TREE_TYPE (oper)) == ARRAY_TYPE))
2650     {
2651       /* Similar to the offset computed above, see if the array index
2652 	 is a compile-time constant.  If so, and unless the offset was
2653 	 not a compile-time constant, use the index to determine the
2654 	 size of the buffer.  Otherwise, use the entire array as
2655 	 an optimistic estimate of the size.  */
2656       const_tree adj = fold_non_dependent_expr (TREE_OPERAND (oper, 1));
2657       if (!use_obj_size && CONSTANT_CLASS_P (adj))
2658 	adjust += wi::to_offset (adj);
2659       else
2660 	{
2661 	  use_obj_size = true;
2662 	  adjust = 0;
2663 	}
2664 
2665       oper = TREE_OPERAND (oper, 0);
2666     }
2667 
2668   /* Refers to the declared object that constains the subobject referenced
2669      by OPER.  When the object is initialized, makes it possible to determine
2670      the actual size of a flexible array member used as the buffer passed
2671      as OPER to placement new.  */
2672   tree var_decl = NULL_TREE;
2673   /* True when operand is a COMPONENT_REF, to distinguish flexible array
2674      members from arrays of unspecified size.  */
2675   bool compref = TREE_CODE (oper) == COMPONENT_REF;
2676 
2677   /* For COMPONENT_REF (i.e., a struct member) the size of the entire
2678      enclosing struct.  Used to validate the adjustment (offset) into
2679      an array at the end of a struct.  */
2680   offset_int compsize = 0;
2681 
2682   /* Descend into a struct or union to find the member whose address
2683      is being used as the argument.  */
2684   if (TREE_CODE (oper) == COMPONENT_REF)
2685     {
2686       tree comptype = TREE_TYPE (TREE_OPERAND (oper, 0));
2687       compsize = wi::to_offset (TYPE_SIZE_UNIT (comptype));
2688 
2689       tree op0 = oper;
2690       while (TREE_CODE (op0 = TREE_OPERAND (op0, 0)) == COMPONENT_REF);
2691       STRIP_ANY_LOCATION_WRAPPER (op0);
2692       if (VAR_P (op0))
2693 	var_decl = op0;
2694       oper = TREE_OPERAND (oper, 1);
2695     }
2696 
2697   STRIP_ANY_LOCATION_WRAPPER (oper);
2698   tree opertype = TREE_TYPE (oper);
2699   if ((addr_expr || !INDIRECT_TYPE_P (opertype))
2700       && (VAR_P (oper)
2701 	  || TREE_CODE (oper) == FIELD_DECL
2702 	  || TREE_CODE (oper) == PARM_DECL))
2703     {
2704       /* A possibly optimistic estimate of the number of bytes available
2705 	 in the destination buffer.  */
2706       offset_int bytes_avail = 0;
2707       /* True when the estimate above is in fact the exact size
2708 	 of the destination buffer rather than an estimate.  */
2709       bool exact_size = true;
2710 
2711       /* Treat members of unions and members of structs uniformly, even
2712 	 though the size of a member of a union may be viewed as extending
2713 	 to the end of the union itself (it is by __builtin_object_size).  */
2714       if ((VAR_P (oper) || use_obj_size)
2715 	  && DECL_SIZE_UNIT (oper)
2716 	  && tree_fits_uhwi_p (DECL_SIZE_UNIT (oper)))
2717 	{
2718 	  /* Use the size of the entire array object when the expression
2719 	     refers to a variable or its size depends on an expression
2720 	     that's not a compile-time constant.  */
2721 	  bytes_avail = wi::to_offset (DECL_SIZE_UNIT (oper));
2722 	  exact_size = !use_obj_size;
2723 	}
2724       else if (tree opersize = TYPE_SIZE_UNIT (opertype))
2725 	{
2726 	  /* Use the size of the type of the destination buffer object
2727 	     as the optimistic estimate of the available space in it.
2728 	     Use the maximum possible size for zero-size arrays and
2729 	     flexible array members (except of initialized objects
2730 	     thereof).  */
2731 	  if (TREE_CODE (opersize) == INTEGER_CST)
2732 	    bytes_avail = wi::to_offset (opersize);
2733 	}
2734 
2735       if (bytes_avail == 0)
2736 	{
2737 	  if (var_decl)
2738 	    {
2739 	      /* Constructing into a buffer provided by the flexible array
2740 		 member of a declared object (which is permitted as a G++
2741 		 extension).  If the array member has been initialized,
2742 		 determine its size from the initializer.  Otherwise,
2743 		 the array size is zero.  */
2744 	      if (tree init = find_flexarray_init (oper,
2745 						   DECL_INITIAL (var_decl)))
2746 		bytes_avail = wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (init)));
2747 	    }
2748 	  else
2749 	    bytes_avail = (wi::to_offset (TYPE_MAX_VALUE (ptrdiff_type_node))
2750 			   - compsize);
2751 	}
2752 
2753       tree_code oper_code = TREE_CODE (opertype);
2754 
2755       if (compref && oper_code == ARRAY_TYPE)
2756 	{
2757 	  tree nelts = array_type_nelts_top (opertype);
2758 	  tree nelts_cst = maybe_constant_value (nelts);
2759 	  if (TREE_CODE (nelts_cst) == INTEGER_CST
2760 	      && integer_onep (nelts_cst)
2761 	      && !var_decl
2762 	      && warn_placement_new < 2)
2763 	    return;
2764 	}
2765 
2766       /* Reduce the size of the buffer by the adjustment computed above
2767 	 from the offset and/or the index into the array.  */
2768       if (bytes_avail < adjust || adjust < 0)
2769 	bytes_avail = 0;
2770       else
2771 	{
2772 	  tree elttype = (TREE_CODE (opertype) == ARRAY_TYPE
2773 			  ? TREE_TYPE (opertype) : opertype);
2774 	  if (tree eltsize = TYPE_SIZE_UNIT (elttype))
2775 	    {
2776 	      bytes_avail -= adjust * wi::to_offset (eltsize);
2777 	      if (bytes_avail < 0)
2778 		bytes_avail = 0;
2779 	    }
2780 	}
2781 
2782       /* The minimum amount of space needed for the allocation.  This
2783 	 is an optimistic estimate that makes it possible to detect
2784 	 placement new invocation for some undersize buffers but not
2785 	 others.  */
2786       offset_int bytes_need;
2787 
2788       if (nelts)
2789 	nelts = fold_for_warn (nelts);
2790 
2791       if (CONSTANT_CLASS_P (size))
2792 	bytes_need = wi::to_offset (size);
2793       else if (nelts && CONSTANT_CLASS_P (nelts))
2794 	bytes_need = (wi::to_offset (nelts)
2795 		      * wi::to_offset (TYPE_SIZE_UNIT (type)));
2796       else if (tree_fits_uhwi_p (TYPE_SIZE_UNIT (type)))
2797 	bytes_need = wi::to_offset (TYPE_SIZE_UNIT (type));
2798       else
2799 	{
2800 	  /* The type is a VLA.  */
2801 	  return;
2802 	}
2803 
2804       if (bytes_avail < bytes_need)
2805 	{
2806 	  if (nelts)
2807 	    if (CONSTANT_CLASS_P (nelts))
2808 	      warning_at (loc, OPT_Wplacement_new_,
2809 			  exact_size ?
2810 			  "placement new constructing an object of type "
2811 			  "%<%T [%wu]%> and size %qwu in a region of type %qT "
2812 			  "and size %qwi"
2813 			  : "placement new constructing an object of type "
2814 			  "%<%T [%wu]%> and size %qwu in a region of type %qT "
2815 			  "and size at most %qwu",
2816 			  type, tree_to_uhwi (nelts), bytes_need.to_uhwi (),
2817 			  opertype, bytes_avail.to_uhwi ());
2818 	    else
2819 	      warning_at (loc, OPT_Wplacement_new_,
2820 			  exact_size ?
2821 			  "placement new constructing an array of objects "
2822 			  "of type %qT and size %qwu in a region of type %qT "
2823 			  "and size %qwi"
2824 			  : "placement new constructing an array of objects "
2825 			  "of type %qT and size %qwu in a region of type %qT "
2826 			  "and size at most %qwu",
2827 			  type, bytes_need.to_uhwi (), opertype,
2828 			  bytes_avail.to_uhwi ());
2829 	  else
2830 	    warning_at (loc, OPT_Wplacement_new_,
2831 			exact_size ?
2832 			"placement new constructing an object of type %qT "
2833 			"and size %qwu in a region of type %qT and size %qwi"
2834 			: "placement new constructing an object of type %qT "
2835 			"and size %qwu in a region of type %qT and size "
2836 			"at most %qwu",
2837 			type, bytes_need.to_uhwi (), opertype,
2838 			bytes_avail.to_uhwi ());
2839 	}
2840     }
2841 }
2842 
2843 /* True if alignof(T) > __STDCPP_DEFAULT_NEW_ALIGNMENT__.  */
2844 
2845 bool
type_has_new_extended_alignment(tree t)2846 type_has_new_extended_alignment (tree t)
2847 {
2848   return (aligned_new_threshold
2849 	  && TYPE_ALIGN_UNIT (t) > (unsigned)aligned_new_threshold);
2850 }
2851 
2852 /* Return the alignment we expect malloc to guarantee.  This should just be
2853    MALLOC_ABI_ALIGNMENT, but that macro defaults to only BITS_PER_WORD for some
2854    reason, so don't let the threshold be smaller than max_align_t_align.  */
2855 
2856 unsigned
malloc_alignment()2857 malloc_alignment ()
2858 {
2859   return MAX (max_align_t_align(), MALLOC_ABI_ALIGNMENT);
2860 }
2861 
2862 /* Determine whether an allocation function is a namespace-scope
2863    non-replaceable placement new function. See DR 1748.  */
2864 static bool
std_placement_new_fn_p(tree alloc_fn)2865 std_placement_new_fn_p (tree alloc_fn)
2866 {
2867   if (DECL_NAMESPACE_SCOPE_P (alloc_fn))
2868     {
2869       tree first_arg = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
2870       if ((TREE_VALUE (first_arg) == ptr_type_node)
2871 	  && TREE_CHAIN (first_arg) == void_list_node)
2872 	return true;
2873     }
2874   return false;
2875 }
2876 
2877 /* For element type ELT_TYPE, return the appropriate type of the heap object
2878    containing such element(s).  COOKIE_SIZE is NULL or the size of cookie
2879    in bytes.  FULL_SIZE is NULL if it is unknown how big the heap allocation
2880    will be, otherwise size of the heap object.  If COOKIE_SIZE is NULL,
2881    return array type ELT_TYPE[FULL_SIZE / sizeof(ELT_TYPE)], otherwise return
2882    struct { size_t[COOKIE_SIZE/sizeof(size_t)]; ELT_TYPE[N]; }
2883    where N is nothing (flexible array member) if FULL_SIZE is NULL, otherwise
2884    it is computed such that the size of the struct fits into FULL_SIZE.  */
2885 
2886 tree
build_new_constexpr_heap_type(tree elt_type,tree cookie_size,tree full_size)2887 build_new_constexpr_heap_type (tree elt_type, tree cookie_size, tree full_size)
2888 {
2889   gcc_assert (cookie_size == NULL_TREE || tree_fits_uhwi_p (cookie_size));
2890   gcc_assert (full_size == NULL_TREE || tree_fits_uhwi_p (full_size));
2891   unsigned HOST_WIDE_INT csz = cookie_size ? tree_to_uhwi (cookie_size) : 0;
2892   tree itype2 = NULL_TREE;
2893   if (full_size)
2894     {
2895       unsigned HOST_WIDE_INT fsz = tree_to_uhwi (full_size);
2896       gcc_assert (fsz >= csz);
2897       fsz -= csz;
2898       fsz /= int_size_in_bytes (elt_type);
2899       itype2 = build_index_type (size_int (fsz - 1));
2900       if (!cookie_size)
2901 	return build_cplus_array_type (elt_type, itype2);
2902     }
2903   else
2904     gcc_assert (cookie_size);
2905   csz /= int_size_in_bytes (sizetype);
2906   tree itype1 = build_index_type (size_int (csz - 1));
2907   tree atype1 = build_cplus_array_type (sizetype, itype1);
2908   tree atype2 = build_cplus_array_type (elt_type, itype2);
2909   tree rtype = cxx_make_type (RECORD_TYPE);
2910   TYPE_NAME (rtype) = heap_identifier;
2911   tree fld1 = build_decl (UNKNOWN_LOCATION, FIELD_DECL, NULL_TREE, atype1);
2912   tree fld2 = build_decl (UNKNOWN_LOCATION, FIELD_DECL, NULL_TREE, atype2);
2913   DECL_FIELD_CONTEXT (fld1) = rtype;
2914   DECL_FIELD_CONTEXT (fld2) = rtype;
2915   DECL_ARTIFICIAL (fld1) = true;
2916   DECL_ARTIFICIAL (fld2) = true;
2917   TYPE_FIELDS (rtype) = fld1;
2918   DECL_CHAIN (fld1) = fld2;
2919   layout_type (rtype);
2920   return rtype;
2921 }
2922 
2923 /* Help the constexpr code to find the right type for the heap variable
2924    by adding a NOP_EXPR around ALLOC_CALL if needed for cookie_size.
2925    Return ALLOC_CALL or ALLOC_CALL cast to a pointer to
2926    struct { size_t[cookie_size/sizeof(size_t)]; elt_type[]; }.  */
2927 
2928 static tree
maybe_wrap_new_for_constexpr(tree alloc_call,tree elt_type,tree cookie_size)2929 maybe_wrap_new_for_constexpr (tree alloc_call, tree elt_type, tree cookie_size)
2930 {
2931   if (cxx_dialect < cxx2a)
2932     return alloc_call;
2933 
2934   if (current_function_decl != NULL_TREE
2935       && !DECL_DECLARED_CONSTEXPR_P (current_function_decl))
2936     return alloc_call;
2937 
2938   tree call_expr = extract_call_expr (alloc_call);
2939   if (call_expr == error_mark_node)
2940     return alloc_call;
2941 
2942   tree alloc_call_fndecl = cp_get_callee_fndecl_nofold (call_expr);
2943   if (alloc_call_fndecl == NULL_TREE
2944       || !IDENTIFIER_NEW_OP_P (DECL_NAME (alloc_call_fndecl))
2945       || CP_DECL_CONTEXT (alloc_call_fndecl) != global_namespace)
2946     return alloc_call;
2947 
2948   tree rtype = build_new_constexpr_heap_type (elt_type, cookie_size,
2949 					      NULL_TREE);
2950   return build_nop (build_pointer_type (rtype), alloc_call);
2951 }
2952 
2953 /* Generate code for a new-expression, including calling the "operator
2954    new" function, initializing the object, and, if an exception occurs
2955    during construction, cleaning up.  The arguments are as for
2956    build_raw_new_expr.  This may change PLACEMENT and INIT.
2957    TYPE is the type of the object being constructed, possibly an array
2958    of NELTS elements when NELTS is non-null (in "new T[NELTS]", T may
2959    be an array of the form U[inner], with the whole expression being
2960    "new U[NELTS][inner]").  */
2961 
2962 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)2963 build_new_1 (vec<tree, va_gc> **placement, tree type, tree nelts,
2964 	     vec<tree, va_gc> **init, bool globally_qualified_p,
2965 	     tsubst_flags_t complain)
2966 {
2967   tree size, rval;
2968   /* True iff this is a call to "operator new[]" instead of just
2969      "operator new".  */
2970   bool array_p = false;
2971   /* If ARRAY_P is true, the element type of the array.  This is never
2972      an ARRAY_TYPE; for something like "new int[3][4]", the
2973      ELT_TYPE is "int".  If ARRAY_P is false, this is the same type as
2974      TYPE.  */
2975   tree elt_type;
2976   /* The type of the new-expression.  (This type is always a pointer
2977      type.)  */
2978   tree pointer_type;
2979   tree non_const_pointer_type;
2980   /* The most significant array bound in int[OUTER_NELTS][inner].  */
2981   tree outer_nelts = NULL_TREE;
2982   /* For arrays with a non-constant number of elements, a bounds checks
2983      on the NELTS parameter to avoid integer overflow at runtime. */
2984   tree outer_nelts_check = NULL_TREE;
2985   bool outer_nelts_from_type = false;
2986   /* Number of the "inner" elements in "new T[OUTER_NELTS][inner]".  */
2987   offset_int inner_nelts_count = 1;
2988   tree alloc_call, alloc_expr;
2989   /* Size of the inner array elements (those with constant dimensions). */
2990   offset_int inner_size;
2991   /* The address returned by the call to "operator new".  This node is
2992      a VAR_DECL and is therefore reusable.  */
2993   tree alloc_node;
2994   tree alloc_fn;
2995   tree cookie_expr, init_expr;
2996   int nothrow, check_new;
2997   /* If non-NULL, the number of extra bytes to allocate at the
2998      beginning of the storage allocated for an array-new expression in
2999      order to store the number of elements.  */
3000   tree cookie_size = NULL_TREE;
3001   tree placement_first;
3002   tree placement_expr = NULL_TREE;
3003   /* True if the function we are calling is a placement allocation
3004      function.  */
3005   bool placement_allocation_fn_p;
3006   /* True if the storage must be initialized, either by a constructor
3007      or due to an explicit new-initializer.  */
3008   bool is_initialized;
3009   /* The address of the thing allocated, not including any cookie.  In
3010      particular, if an array cookie is in use, DATA_ADDR is the
3011      address of the first array element.  This node is a VAR_DECL, and
3012      is therefore reusable.  */
3013   tree data_addr;
3014   tree init_preeval_expr = NULL_TREE;
3015   tree orig_type = type;
3016 
3017   if (nelts)
3018     {
3019       outer_nelts = nelts;
3020       array_p = true;
3021     }
3022   else if (TREE_CODE (type) == ARRAY_TYPE)
3023     {
3024       /* Transforms new (T[N]) to new T[N].  The former is a GNU
3025 	 extension for variable N.  (This also covers new T where T is
3026 	 a VLA typedef.)  */
3027       array_p = true;
3028       nelts = array_type_nelts_top (type);
3029       outer_nelts = nelts;
3030       type = TREE_TYPE (type);
3031       outer_nelts_from_type = true;
3032     }
3033 
3034   /* Lots of logic below depends on whether we have a constant number of
3035      elements, so go ahead and fold it now.  */
3036   const_tree cst_outer_nelts = fold_non_dependent_expr (outer_nelts, complain);
3037 
3038   /* If our base type is an array, then make sure we know how many elements
3039      it has.  */
3040   for (elt_type = type;
3041        TREE_CODE (elt_type) == ARRAY_TYPE;
3042        elt_type = TREE_TYPE (elt_type))
3043     {
3044       tree inner_nelts = array_type_nelts_top (elt_type);
3045       tree inner_nelts_cst = maybe_constant_value (inner_nelts);
3046       if (TREE_CODE (inner_nelts_cst) == INTEGER_CST)
3047 	{
3048 	  wi::overflow_type overflow;
3049 	  offset_int result = wi::mul (wi::to_offset (inner_nelts_cst),
3050 				       inner_nelts_count, SIGNED, &overflow);
3051 	  if (overflow)
3052 	    {
3053 	      if (complain & tf_error)
3054 		error ("integer overflow in array size");
3055 	      nelts = error_mark_node;
3056 	    }
3057 	  inner_nelts_count = result;
3058 	}
3059       else
3060 	{
3061 	  if (complain & tf_error)
3062 	    {
3063 	      error_at (cp_expr_loc_or_input_loc (inner_nelts),
3064 			"array size in new-expression must be constant");
3065 	      cxx_constant_value(inner_nelts);
3066 	    }
3067 	  nelts = error_mark_node;
3068 	}
3069       if (nelts != error_mark_node)
3070 	nelts = cp_build_binary_op (input_location,
3071 				    MULT_EXPR, nelts,
3072 				    inner_nelts_cst,
3073 				    complain);
3074     }
3075 
3076   if (!verify_type_context (input_location, TCTX_ALLOCATION, elt_type,
3077 			    !(complain & tf_error)))
3078     return error_mark_node;
3079 
3080   if (variably_modified_type_p (elt_type, NULL_TREE) && (complain & tf_error))
3081     {
3082       error ("variably modified type not allowed in new-expression");
3083       return error_mark_node;
3084     }
3085 
3086   if (nelts == error_mark_node)
3087     return error_mark_node;
3088 
3089   /* Warn if we performed the (T[N]) to T[N] transformation and N is
3090      variable.  */
3091   if (outer_nelts_from_type
3092       && !TREE_CONSTANT (cst_outer_nelts))
3093     {
3094       if (complain & tf_warning_or_error)
3095 	{
3096 	  pedwarn (cp_expr_loc_or_input_loc (outer_nelts), OPT_Wvla,
3097 		   typedef_variant_p (orig_type)
3098 		   ? G_("non-constant array new length must be specified "
3099 			"directly, not by %<typedef%>")
3100 		   : G_("non-constant array new length must be specified "
3101 			"without parentheses around the type-id"));
3102 	}
3103       else
3104 	return error_mark_node;
3105     }
3106 
3107   if (VOID_TYPE_P (elt_type))
3108     {
3109       if (complain & tf_error)
3110 	error ("invalid type %<void%> for %<new%>");
3111       return error_mark_node;
3112     }
3113 
3114   if (is_std_init_list (elt_type))
3115     warning (OPT_Winit_list_lifetime,
3116 	     "%<new%> of %<initializer_list%> does not "
3117 	     "extend the lifetime of the underlying array");
3118 
3119   if (abstract_virtuals_error_sfinae (ACU_NEW, elt_type, complain))
3120     return error_mark_node;
3121 
3122   is_initialized = (type_build_ctor_call (elt_type) || *init != NULL);
3123 
3124   if (*init == NULL && cxx_dialect < cxx11)
3125     {
3126       bool maybe_uninitialized_error = false;
3127       /* A program that calls for default-initialization [...] of an
3128 	 entity of reference type is ill-formed. */
3129       if (CLASSTYPE_REF_FIELDS_NEED_INIT (elt_type))
3130 	maybe_uninitialized_error = true;
3131 
3132       /* A new-expression that creates an object of type T initializes
3133 	 that object as follows:
3134       - If the new-initializer is omitted:
3135         -- If T is a (possibly cv-qualified) non-POD class type
3136 	   (or array thereof), the object is default-initialized (8.5).
3137 	   [...]
3138         -- Otherwise, the object created has indeterminate
3139 	   value. If T is a const-qualified type, or a (possibly
3140 	   cv-qualified) POD class type (or array thereof)
3141 	   containing (directly or indirectly) a member of
3142 	   const-qualified type, the program is ill-formed; */
3143 
3144       if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (elt_type))
3145 	maybe_uninitialized_error = true;
3146 
3147       if (maybe_uninitialized_error
3148 	  && diagnose_uninitialized_cst_or_ref_member (elt_type,
3149 						       /*using_new=*/true,
3150 						       complain & tf_error))
3151 	return error_mark_node;
3152     }
3153 
3154   if (CP_TYPE_CONST_P (elt_type) && *init == NULL
3155       && default_init_uninitialized_part (elt_type))
3156     {
3157       if (complain & tf_error)
3158         error ("uninitialized const in %<new%> of %q#T", elt_type);
3159       return error_mark_node;
3160     }
3161 
3162   size = size_in_bytes (elt_type);
3163   if (array_p)
3164     {
3165       /* Maximum available size in bytes.  Half of the address space
3166 	 minus the cookie size.  */
3167       offset_int max_size
3168 	= wi::set_bit_in_zero <offset_int> (TYPE_PRECISION (sizetype) - 1);
3169       /* Maximum number of outer elements which can be allocated. */
3170       offset_int max_outer_nelts;
3171       tree max_outer_nelts_tree;
3172 
3173       gcc_assert (TREE_CODE (size) == INTEGER_CST);
3174       cookie_size = targetm.cxx.get_cookie_size (elt_type);
3175       gcc_assert (TREE_CODE (cookie_size) == INTEGER_CST);
3176       gcc_checking_assert (wi::ltu_p (wi::to_offset (cookie_size), max_size));
3177       /* Unconditionally subtract the cookie size.  This decreases the
3178 	 maximum object size and is safe even if we choose not to use
3179 	 a cookie after all.  */
3180       max_size -= wi::to_offset (cookie_size);
3181       wi::overflow_type overflow;
3182       inner_size = wi::mul (wi::to_offset (size), inner_nelts_count, SIGNED,
3183 			    &overflow);
3184       if (overflow || wi::gtu_p (inner_size, max_size))
3185 	{
3186 	  if (complain & tf_error)
3187 	    {
3188 	      cst_size_error error;
3189 	      if (overflow)
3190 		error = cst_size_overflow;
3191 	      else
3192 		{
3193 		  error = cst_size_too_big;
3194 		  size = size_binop (MULT_EXPR, size,
3195 				     wide_int_to_tree (sizetype,
3196 						       inner_nelts_count));
3197 		  size = cp_fully_fold (size);
3198 		}
3199 	      invalid_array_size_error (input_location, error, size,
3200 					/*name=*/NULL_TREE);
3201 	    }
3202 	  return error_mark_node;
3203 	}
3204 
3205       max_outer_nelts = wi::udiv_trunc (max_size, inner_size);
3206       max_outer_nelts_tree = wide_int_to_tree (sizetype, max_outer_nelts);
3207 
3208       size = size_binop (MULT_EXPR, size, fold_convert (sizetype, nelts));
3209 
3210       if (TREE_CODE (cst_outer_nelts) == INTEGER_CST)
3211 	{
3212 	  if (tree_int_cst_lt (max_outer_nelts_tree, cst_outer_nelts))
3213 	    {
3214 	      /* When the array size is constant, check it at compile time
3215 		 to make sure it doesn't exceed the implementation-defined
3216 		 maximum, as required by C++ 14 (in C++ 11 this requirement
3217 		 isn't explicitly stated but it's enforced anyway -- see
3218 		 grokdeclarator in cp/decl.c).  */
3219 	      if (complain & tf_error)
3220 		{
3221 		  size = cp_fully_fold (size);
3222 		  invalid_array_size_error (input_location, cst_size_too_big,
3223 					    size, NULL_TREE);
3224 		}
3225 	      return error_mark_node;
3226 	    }
3227 	}
3228       else
3229  	{
3230 	  /* When a runtime check is necessary because the array size
3231 	     isn't constant, keep only the top-most seven bits (starting
3232 	     with the most significant non-zero bit) of the maximum size
3233 	     to compare the array size against, to simplify encoding the
3234 	     constant maximum size in the instruction stream.  */
3235 
3236 	  unsigned shift = (max_outer_nelts.get_precision ()) - 7
3237 	    - wi::clz (max_outer_nelts);
3238 	  max_outer_nelts = (max_outer_nelts >> shift) << shift;
3239 
3240           outer_nelts_check = fold_build2 (LE_EXPR, boolean_type_node,
3241 					   outer_nelts,
3242 					   max_outer_nelts_tree);
3243 	}
3244     }
3245 
3246   tree align_arg = NULL_TREE;
3247   if (type_has_new_extended_alignment (elt_type))
3248     align_arg = build_int_cst (align_type_node, TYPE_ALIGN_UNIT (elt_type));
3249 
3250   alloc_fn = NULL_TREE;
3251 
3252   /* If PLACEMENT is a single simple pointer type not passed by
3253      reference, prepare to capture it in a temporary variable.  Do
3254      this now, since PLACEMENT will change in the calls below.  */
3255   placement_first = NULL_TREE;
3256   if (vec_safe_length (*placement) == 1
3257       && (TYPE_PTR_P (TREE_TYPE ((**placement)[0]))))
3258     placement_first = (**placement)[0];
3259 
3260   bool member_new_p = false;
3261 
3262   /* Allocate the object.  */
3263   tree fnname;
3264   tree fns;
3265 
3266   fnname = ovl_op_identifier (false, array_p ? VEC_NEW_EXPR : NEW_EXPR);
3267 
3268   member_new_p = !globally_qualified_p
3269 		 && CLASS_TYPE_P (elt_type)
3270 		 && (array_p
3271 		     ? TYPE_HAS_ARRAY_NEW_OPERATOR (elt_type)
3272 		     : TYPE_HAS_NEW_OPERATOR (elt_type));
3273 
3274   if (member_new_p)
3275     {
3276       /* Use a class-specific operator new.  */
3277       /* If a cookie is required, add some extra space.  */
3278       if (array_p && TYPE_VEC_NEW_USES_COOKIE (elt_type))
3279 	size = size_binop (PLUS_EXPR, size, cookie_size);
3280       else
3281 	{
3282 	  cookie_size = NULL_TREE;
3283 	  /* No size arithmetic necessary, so the size check is
3284 	     not needed. */
3285 	  if (outer_nelts_check != NULL && inner_size == 1)
3286 	    outer_nelts_check = NULL_TREE;
3287 	}
3288       /* Perform the overflow check.  */
3289       tree errval = TYPE_MAX_VALUE (sizetype);
3290       if (cxx_dialect >= cxx11 && flag_exceptions)
3291 	errval = throw_bad_array_new_length ();
3292       if (outer_nelts_check != NULL_TREE)
3293 	size = fold_build3 (COND_EXPR, sizetype, outer_nelts_check,
3294 			    size, errval);
3295       /* Create the argument list.  */
3296       vec_safe_insert (*placement, 0, size);
3297       /* Do name-lookup to find the appropriate operator.  */
3298       fns = lookup_fnfields (elt_type, fnname, /*protect=*/2);
3299       if (fns == NULL_TREE)
3300 	{
3301 	  if (complain & tf_error)
3302 	    error ("no suitable %qD found in class %qT", fnname, elt_type);
3303 	  return error_mark_node;
3304 	}
3305       if (TREE_CODE (fns) == TREE_LIST)
3306 	{
3307 	  if (complain & tf_error)
3308 	    {
3309 	      error ("request for member %qD is ambiguous", fnname);
3310 	      print_candidates (fns);
3311 	    }
3312 	  return error_mark_node;
3313 	}
3314       tree dummy = build_dummy_object (elt_type);
3315       alloc_call = NULL_TREE;
3316       if (align_arg)
3317 	{
3318 	  vec<tree, va_gc> *align_args
3319 	    = vec_copy_and_insert (*placement, align_arg, 1);
3320 	  alloc_call
3321 	    = build_new_method_call (dummy, fns, &align_args,
3322 				     /*conversion_path=*/NULL_TREE,
3323 				     LOOKUP_NORMAL, &alloc_fn, tf_none);
3324 	  /* If no matching function is found and the allocated object type
3325 	     has new-extended alignment, the alignment argument is removed
3326 	     from the argument list, and overload resolution is performed
3327 	     again.  */
3328 	  if (alloc_call == error_mark_node)
3329 	    alloc_call = NULL_TREE;
3330 	}
3331       if (!alloc_call)
3332 	alloc_call = build_new_method_call (dummy, fns, placement,
3333 					    /*conversion_path=*/NULL_TREE,
3334 					    LOOKUP_NORMAL,
3335 					    &alloc_fn, complain);
3336     }
3337   else
3338     {
3339       /* Use a global operator new.  */
3340       /* See if a cookie might be required.  */
3341       if (!(array_p && TYPE_VEC_NEW_USES_COOKIE (elt_type)))
3342 	{
3343 	  cookie_size = NULL_TREE;
3344 	  /* No size arithmetic necessary, so the size check is
3345 	     not needed. */
3346 	  if (outer_nelts_check != NULL && inner_size == 1)
3347 	    outer_nelts_check = NULL_TREE;
3348 	}
3349 
3350       alloc_call = build_operator_new_call (fnname, placement,
3351 					    &size, &cookie_size,
3352 					    align_arg, outer_nelts_check,
3353 					    &alloc_fn, complain);
3354     }
3355 
3356   if (alloc_call == error_mark_node)
3357     return error_mark_node;
3358 
3359   gcc_assert (alloc_fn != NULL_TREE);
3360 
3361   /* Now, check to see if this function is actually a placement
3362      allocation function.  This can happen even when PLACEMENT is NULL
3363      because we might have something like:
3364 
3365        struct S { void* operator new (size_t, int i = 0); };
3366 
3367      A call to `new S' will get this allocation function, even though
3368      there is no explicit placement argument.  If there is more than
3369      one argument, or there are variable arguments, then this is a
3370      placement allocation function.  */
3371   placement_allocation_fn_p
3372     = (type_num_arguments (TREE_TYPE (alloc_fn)) > 1
3373        || varargs_function_p (alloc_fn));
3374 
3375   if (warn_aligned_new
3376       && !placement_allocation_fn_p
3377       && TYPE_ALIGN (elt_type) > malloc_alignment ()
3378       && (warn_aligned_new > 1
3379 	  || CP_DECL_CONTEXT (alloc_fn) == global_namespace)
3380       && !aligned_allocation_fn_p (alloc_fn))
3381     {
3382       auto_diagnostic_group d;
3383       if (warning (OPT_Waligned_new_, "%<new%> of type %qT with extended "
3384 		   "alignment %d", elt_type, TYPE_ALIGN_UNIT (elt_type)))
3385 	{
3386 	  inform (input_location, "uses %qD, which does not have an alignment "
3387 		  "parameter", alloc_fn);
3388 	  if (!aligned_new_threshold)
3389 	    inform (input_location, "use %<-faligned-new%> to enable C++17 "
3390 				    "over-aligned new support");
3391 	}
3392     }
3393 
3394   /* If we found a simple case of PLACEMENT_EXPR above, then copy it
3395      into a temporary variable.  */
3396   if (!processing_template_decl
3397       && TREE_CODE (alloc_call) == CALL_EXPR
3398       && call_expr_nargs (alloc_call) == 2
3399       && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (alloc_call, 0))) == INTEGER_TYPE
3400       && TYPE_PTR_P (TREE_TYPE (CALL_EXPR_ARG (alloc_call, 1))))
3401     {
3402       tree placement = CALL_EXPR_ARG (alloc_call, 1);
3403 
3404       if (placement_first != NULL_TREE
3405 	  && (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (TREE_TYPE (placement)))
3406 	      || VOID_TYPE_P (TREE_TYPE (TREE_TYPE (placement)))))
3407 	{
3408 	  placement_expr = get_target_expr (placement_first);
3409 	  CALL_EXPR_ARG (alloc_call, 1)
3410 	    = fold_convert (TREE_TYPE (placement), placement_expr);
3411 	}
3412 
3413       if (!member_new_p
3414 	  && VOID_TYPE_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_ARG (alloc_call, 1)))))
3415 	{
3416 	  /* Attempt to make the warning point at the operator new argument.  */
3417 	  if (placement_first)
3418 	    placement = placement_first;
3419 
3420 	  warn_placement_new_too_small (orig_type, nelts, size, placement);
3421 	}
3422     }
3423 
3424   tree alloc_call_expr = extract_call_expr (alloc_call);
3425   if (TREE_CODE (alloc_call_expr) == CALL_EXPR)
3426     CALL_FROM_NEW_OR_DELETE_P (alloc_call_expr) = 1;
3427 
3428   if (cookie_size)
3429     alloc_call = maybe_wrap_new_for_constexpr (alloc_call, elt_type,
3430 					       cookie_size);
3431 
3432   /* In the simple case, we can stop now.  */
3433   pointer_type = build_pointer_type (type);
3434   if (!cookie_size && !is_initialized)
3435     return build_nop (pointer_type, alloc_call);
3436 
3437   /* Store the result of the allocation call in a variable so that we can
3438      use it more than once.  */
3439   alloc_expr = get_target_expr (alloc_call);
3440   alloc_node = TARGET_EXPR_SLOT (alloc_expr);
3441 
3442   /* Strip any COMPOUND_EXPRs from ALLOC_CALL.  */
3443   while (TREE_CODE (alloc_call) == COMPOUND_EXPR)
3444     alloc_call = TREE_OPERAND (alloc_call, 1);
3445 
3446   /* Preevaluate the placement args so that we don't reevaluate them for a
3447      placement delete.  */
3448   if (placement_allocation_fn_p)
3449     {
3450       tree inits;
3451       stabilize_call (alloc_call, &inits);
3452       if (inits)
3453 	alloc_expr = build2 (COMPOUND_EXPR, TREE_TYPE (alloc_expr), inits,
3454 			     alloc_expr);
3455     }
3456 
3457   /*        unless an allocation function is declared with an empty  excep-
3458      tion-specification  (_except.spec_),  throw(), it indicates failure to
3459      allocate storage by throwing a bad_alloc exception  (clause  _except_,
3460      _lib.bad.alloc_); it returns a non-null pointer otherwise If the allo-
3461      cation function is declared  with  an  empty  exception-specification,
3462      throw(), it returns null to indicate failure to allocate storage and a
3463      non-null pointer otherwise.
3464 
3465      So check for a null exception spec on the op new we just called.  */
3466 
3467   nothrow = TYPE_NOTHROW_P (TREE_TYPE (alloc_fn));
3468   check_new
3469     = flag_check_new || (nothrow && !std_placement_new_fn_p (alloc_fn));
3470 
3471   if (cookie_size)
3472     {
3473       tree cookie;
3474       tree cookie_ptr;
3475       tree size_ptr_type;
3476 
3477       /* Adjust so we're pointing to the start of the object.  */
3478       data_addr = fold_build_pointer_plus (alloc_node, cookie_size);
3479 
3480       /* Store the number of bytes allocated so that we can know how
3481 	 many elements to destroy later.  We use the last sizeof
3482 	 (size_t) bytes to store the number of elements.  */
3483       cookie_ptr = size_binop (MINUS_EXPR, cookie_size, size_in_bytes (sizetype));
3484       cookie_ptr = fold_build_pointer_plus_loc (input_location,
3485 						alloc_node, cookie_ptr);
3486       size_ptr_type = build_pointer_type (sizetype);
3487       cookie_ptr = fold_convert (size_ptr_type, cookie_ptr);
3488       cookie = cp_build_fold_indirect_ref (cookie_ptr);
3489 
3490       cookie_expr = build2 (MODIFY_EXPR, sizetype, cookie, nelts);
3491 
3492       if (targetm.cxx.cookie_has_size ())
3493 	{
3494 	  /* Also store the element size.  */
3495 	  cookie_ptr = fold_build_pointer_plus (cookie_ptr,
3496 			       fold_build1_loc (input_location,
3497 						NEGATE_EXPR, sizetype,
3498 						size_in_bytes (sizetype)));
3499 
3500 	  cookie = cp_build_fold_indirect_ref (cookie_ptr);
3501 	  cookie = build2 (MODIFY_EXPR, sizetype, cookie,
3502 			   size_in_bytes (elt_type));
3503 	  cookie_expr = build2 (COMPOUND_EXPR, TREE_TYPE (cookie_expr),
3504 				cookie, cookie_expr);
3505 	}
3506     }
3507   else
3508     {
3509       cookie_expr = NULL_TREE;
3510       data_addr = alloc_node;
3511     }
3512 
3513   /* Now use a pointer to the type we've actually allocated.  */
3514 
3515   /* But we want to operate on a non-const version to start with,
3516      since we'll be modifying the elements.  */
3517   non_const_pointer_type = build_pointer_type
3518     (cp_build_qualified_type (type, cp_type_quals (type) & ~TYPE_QUAL_CONST));
3519 
3520   data_addr = fold_convert (non_const_pointer_type, data_addr);
3521   /* Any further uses of alloc_node will want this type, too.  */
3522   alloc_node = fold_convert (non_const_pointer_type, alloc_node);
3523 
3524   /* Now initialize the allocated object.  Note that we preevaluate the
3525      initialization expression, apart from the actual constructor call or
3526      assignment--we do this because we want to delay the allocation as long
3527      as possible in order to minimize the size of the exception region for
3528      placement delete.  */
3529   if (is_initialized)
3530     {
3531       bool stable;
3532       bool explicit_value_init_p = false;
3533 
3534       if (*init != NULL && (*init)->is_empty ())
3535 	{
3536 	  *init = NULL;
3537 	  explicit_value_init_p = true;
3538 	}
3539 
3540       if (processing_template_decl)
3541 	{
3542 	  /* Avoid an ICE when converting to a base in build_simple_base_path.
3543 	     We'll throw this all away anyway, and build_new will create
3544 	     a NEW_EXPR.  */
3545 	  tree t = fold_convert (build_pointer_type (elt_type), data_addr);
3546 	  /* build_value_init doesn't work in templates, and we don't need
3547 	     the initializer anyway since we're going to throw it away and
3548 	     rebuild it at instantiation time, so just build up a single
3549 	     constructor call to get any appropriate diagnostics.  */
3550 	  init_expr = cp_build_fold_indirect_ref (t);
3551 	  if (type_build_ctor_call (elt_type))
3552 	    init_expr = build_special_member_call (init_expr,
3553 						   complete_ctor_identifier,
3554 						   init, elt_type,
3555 						   LOOKUP_NORMAL,
3556 						   complain);
3557 	  stable = stabilize_init (init_expr, &init_preeval_expr);
3558 	}
3559       else if (array_p)
3560 	{
3561 	  tree vecinit = NULL_TREE;
3562 	  if (vec_safe_length (*init) == 1
3563 	      && DIRECT_LIST_INIT_P ((**init)[0]))
3564 	    {
3565 	      vecinit = (**init)[0];
3566 	      if (CONSTRUCTOR_NELTS (vecinit) == 0)
3567 		/* List-value-initialization, leave it alone.  */;
3568 	      else
3569 		{
3570 		  tree arraytype, domain;
3571 		  if (TREE_CONSTANT (nelts))
3572 		    domain = compute_array_index_type (NULL_TREE, nelts,
3573 						       complain);
3574 		  else
3575 		    /* We'll check the length at runtime.  */
3576 		    domain = NULL_TREE;
3577 		  arraytype = build_cplus_array_type (type, domain);
3578 		  vecinit = digest_init (arraytype, vecinit, complain);
3579 		}
3580 	    }
3581 	  else if (*init)
3582             {
3583               if (complain & tf_error)
3584                 error ("parenthesized initializer in array new");
3585 	      return error_mark_node;
3586             }
3587 	  init_expr
3588 	    = build_vec_init (data_addr,
3589 			      cp_build_binary_op (input_location,
3590 						  MINUS_EXPR, outer_nelts,
3591 						  integer_one_node,
3592 						  complain),
3593 			      vecinit,
3594 			      explicit_value_init_p,
3595 			      /*from_array=*/0,
3596                               complain);
3597 
3598 	  /* An array initialization is stable because the initialization
3599 	     of each element is a full-expression, so the temporaries don't
3600 	     leak out.  */
3601 	  stable = true;
3602 	}
3603       else
3604 	{
3605 	  init_expr = cp_build_fold_indirect_ref (data_addr);
3606 
3607 	  if (type_build_ctor_call (type) && !explicit_value_init_p)
3608 	    {
3609 	      init_expr = build_special_member_call (init_expr,
3610 						     complete_ctor_identifier,
3611 						     init, elt_type,
3612 						     LOOKUP_NORMAL,
3613 						     complain|tf_no_cleanup);
3614 	    }
3615 	  else if (explicit_value_init_p)
3616 	    {
3617 	      /* Something like `new int()'.  NO_CLEANUP is needed so
3618 		 we don't try and build a (possibly ill-formed)
3619 		 destructor.  */
3620 	      tree val = build_value_init (type, complain | tf_no_cleanup);
3621 	      if (val == error_mark_node)
3622 		return error_mark_node;
3623 	      init_expr = build2 (INIT_EXPR, type, init_expr, val);
3624 	    }
3625 	  else
3626 	    {
3627 	      tree ie;
3628 
3629 	      /* We are processing something like `new int (10)', which
3630 		 means allocate an int, and initialize it with 10.
3631 
3632 		 In C++20, also handle `new A(1, 2)'.  */
3633 	      if (cxx_dialect >= cxx2a
3634 		  && AGGREGATE_TYPE_P (type)
3635 		  && (*init)->length () > 1)
3636 		{
3637 		  ie = build_tree_list_vec (*init);
3638 		  ie = build_constructor_from_list (init_list_type_node, ie);
3639 		  CONSTRUCTOR_IS_DIRECT_INIT (ie) = true;
3640 		  CONSTRUCTOR_IS_PAREN_INIT (ie) = true;
3641 		  ie = digest_init (type, ie, complain);
3642 		}
3643 	      else
3644 		ie = build_x_compound_expr_from_vec (*init, "new initializer",
3645 						     complain);
3646 	      init_expr = cp_build_modify_expr (input_location, init_expr,
3647 						INIT_EXPR, ie, complain);
3648 	    }
3649 	  /* If the initializer uses C++14 aggregate NSDMI that refer to the
3650 	     object being initialized, replace them now and don't try to
3651 	     preevaluate.  */
3652 	  bool had_placeholder = false;
3653 	  if (!processing_template_decl
3654 	      && TREE_CODE (init_expr) == INIT_EXPR)
3655 	    TREE_OPERAND (init_expr, 1)
3656 	      = replace_placeholders (TREE_OPERAND (init_expr, 1),
3657 				      TREE_OPERAND (init_expr, 0),
3658 				      &had_placeholder);
3659 	  stable = (!had_placeholder
3660 		    && stabilize_init (init_expr, &init_preeval_expr));
3661 	}
3662 
3663       if (init_expr == error_mark_node)
3664 	return error_mark_node;
3665 
3666       /* If any part of the object initialization terminates by throwing an
3667 	 exception and a suitable deallocation function can be found, the
3668 	 deallocation function is called to free the memory in which the
3669 	 object was being constructed, after which the exception continues
3670 	 to propagate in the context of the new-expression. If no
3671 	 unambiguous matching deallocation function can be found,
3672 	 propagating the exception does not cause the object's memory to be
3673 	 freed.  */
3674       if (flag_exceptions)
3675 	{
3676 	  enum tree_code dcode = array_p ? VEC_DELETE_EXPR : DELETE_EXPR;
3677 	  tree cleanup;
3678 
3679 	  /* The Standard is unclear here, but the right thing to do
3680 	     is to use the same method for finding deallocation
3681 	     functions that we use for finding allocation functions.  */
3682 	  cleanup = (build_op_delete_call
3683 		     (dcode,
3684 		      alloc_node,
3685 		      size,
3686 		      globally_qualified_p,
3687 		      placement_allocation_fn_p ? alloc_call : NULL_TREE,
3688 		      alloc_fn,
3689 		      complain));
3690 
3691 	  if (!cleanup)
3692 	    /* We're done.  */;
3693 	  else if (stable)
3694 	    /* This is much simpler if we were able to preevaluate all of
3695 	       the arguments to the constructor call.  */
3696 	    {
3697 	      /* CLEANUP is compiler-generated, so no diagnostics.  */
3698 	      TREE_NO_WARNING (cleanup) = true;
3699 	      init_expr = build2 (TRY_CATCH_EXPR, void_type_node,
3700 				  init_expr, cleanup);
3701 	      /* Likewise, this try-catch is compiler-generated.  */
3702 	      TREE_NO_WARNING (init_expr) = true;
3703 	    }
3704 	  else
3705 	    /* Ack!  First we allocate the memory.  Then we set our sentry
3706 	       variable to true, and expand a cleanup that deletes the
3707 	       memory if sentry is true.  Then we run the constructor, and
3708 	       finally clear the sentry.
3709 
3710 	       We need to do this because we allocate the space first, so
3711 	       if there are any temporaries with cleanups in the
3712 	       constructor args and we weren't able to preevaluate them, we
3713 	       need this EH region to extend until end of full-expression
3714 	       to preserve nesting.  */
3715 	    {
3716 	      tree end, sentry, begin;
3717 
3718 	      begin = get_target_expr (boolean_true_node);
3719 	      CLEANUP_EH_ONLY (begin) = 1;
3720 
3721 	      sentry = TARGET_EXPR_SLOT (begin);
3722 
3723 	      /* CLEANUP is compiler-generated, so no diagnostics.  */
3724 	      TREE_NO_WARNING (cleanup) = true;
3725 
3726 	      TARGET_EXPR_CLEANUP (begin)
3727 		= build3 (COND_EXPR, void_type_node, sentry,
3728 			  cleanup, void_node);
3729 
3730 	      end = build2 (MODIFY_EXPR, TREE_TYPE (sentry),
3731 			    sentry, boolean_false_node);
3732 
3733 	      init_expr
3734 		= build2 (COMPOUND_EXPR, void_type_node, begin,
3735 			  build2 (COMPOUND_EXPR, void_type_node, init_expr,
3736 				  end));
3737 	      /* Likewise, this is compiler-generated.  */
3738 	      TREE_NO_WARNING (init_expr) = true;
3739 	    }
3740 	}
3741     }
3742   else
3743     init_expr = NULL_TREE;
3744 
3745   /* Now build up the return value in reverse order.  */
3746 
3747   rval = data_addr;
3748 
3749   if (init_expr)
3750     rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), init_expr, rval);
3751   if (cookie_expr)
3752     rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), cookie_expr, rval);
3753 
3754   if (rval == data_addr)
3755     /* If we don't have an initializer or a cookie, strip the TARGET_EXPR
3756        and return the call (which doesn't need to be adjusted).  */
3757     rval = TARGET_EXPR_INITIAL (alloc_expr);
3758   else
3759     {
3760       if (check_new)
3761 	{
3762 	  tree ifexp = cp_build_binary_op (input_location,
3763 					   NE_EXPR, alloc_node,
3764 					   nullptr_node,
3765 					   complain);
3766 	  rval = build_conditional_expr (input_location, ifexp, rval,
3767 					 alloc_node, complain);
3768 	}
3769 
3770       /* Perform the allocation before anything else, so that ALLOC_NODE
3771 	 has been initialized before we start using it.  */
3772       rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), alloc_expr, rval);
3773     }
3774 
3775   if (init_preeval_expr)
3776     rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), init_preeval_expr, rval);
3777 
3778   /* A new-expression is never an lvalue.  */
3779   gcc_assert (!obvalue_p (rval));
3780 
3781   return convert (pointer_type, rval);
3782 }
3783 
3784 /* Generate a representation for a C++ "new" expression.  *PLACEMENT
3785    is a vector of placement-new arguments (or NULL if none).  If NELTS
3786    is NULL, TYPE is the type of the storage to be allocated.  If NELTS
3787    is not NULL, then this is an array-new allocation; TYPE is the type
3788    of the elements in the array and NELTS is the number of elements in
3789    the array.  *INIT, if non-NULL, is the initializer for the new
3790    object, or an empty vector to indicate an initializer of "()".  If
3791    USE_GLOBAL_NEW is true, then the user explicitly wrote "::new"
3792    rather than just "new".  This may change PLACEMENT and INIT.  */
3793 
3794 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)3795 build_new (location_t loc, vec<tree, va_gc> **placement, tree type,
3796 	   tree nelts, vec<tree, va_gc> **init, int use_global_new,
3797 	   tsubst_flags_t complain)
3798 {
3799   tree rval;
3800   vec<tree, va_gc> *orig_placement = NULL;
3801   tree orig_nelts = NULL_TREE;
3802   vec<tree, va_gc> *orig_init = NULL;
3803 
3804   if (type == error_mark_node)
3805     return error_mark_node;
3806 
3807   if (nelts == NULL_TREE
3808       /* Don't do auto deduction where it might affect mangling.  */
3809       && (!processing_template_decl || at_function_scope_p ()))
3810     {
3811       tree auto_node = type_uses_auto (type);
3812       if (auto_node)
3813 	{
3814 	  tree d_init = NULL_TREE;
3815 	  const size_t len = vec_safe_length (*init);
3816 	  /* E.g. new auto(x) must have exactly one element, or
3817 	     a {} initializer will have one element.  */
3818 	  if (len == 1)
3819 	    {
3820 	      d_init = (**init)[0];
3821 	      d_init = resolve_nondeduced_context (d_init, complain);
3822 	    }
3823 	  /* For the rest, e.g. new A(1, 2, 3), create a list.  */
3824 	  else if (len > 1)
3825 	    {
3826 	      unsigned int n;
3827 	      tree t;
3828 	      tree *pp = &d_init;
3829 	      FOR_EACH_VEC_ELT (**init, n, t)
3830 		{
3831 		  t = resolve_nondeduced_context (t, complain);
3832 		  *pp = build_tree_list (NULL_TREE, t);
3833 		  pp = &TREE_CHAIN (*pp);
3834 		}
3835 	    }
3836 	  type = do_auto_deduction (type, d_init, auto_node, complain);
3837 	}
3838     }
3839 
3840   if (processing_template_decl)
3841     {
3842       if (dependent_type_p (type)
3843 	  || any_type_dependent_arguments_p (*placement)
3844 	  || (nelts && type_dependent_expression_p (nelts))
3845 	  || (nelts && *init)
3846 	  || any_type_dependent_arguments_p (*init))
3847 	return build_raw_new_expr (loc, *placement, type, nelts, *init,
3848 				   use_global_new);
3849 
3850       orig_placement = make_tree_vector_copy (*placement);
3851       orig_nelts = nelts;
3852       if (*init)
3853 	{
3854 	  orig_init = make_tree_vector_copy (*init);
3855 	  /* Also copy any CONSTRUCTORs in *init, since reshape_init and
3856 	     digest_init clobber them in place.  */
3857 	  for (unsigned i = 0; i < orig_init->length(); ++i)
3858 	    {
3859 	      tree e = (**init)[i];
3860 	      if (TREE_CODE (e) == CONSTRUCTOR)
3861 		(**init)[i] = copy_node (e);
3862 	    }
3863 	}
3864 
3865       make_args_non_dependent (*placement);
3866       if (nelts)
3867 	nelts = build_non_dependent_expr (nelts);
3868       make_args_non_dependent (*init);
3869     }
3870 
3871   if (nelts)
3872     {
3873       location_t nelts_loc = cp_expr_loc_or_loc (nelts, loc);
3874       if (!build_expr_type_conversion (WANT_INT | WANT_ENUM, nelts, false))
3875         {
3876           if (complain & tf_error)
3877 	    permerror (nelts_loc,
3878 		       "size in array new must have integral type");
3879           else
3880             return error_mark_node;
3881         }
3882 
3883       /* Try to determine the constant value only for the purposes
3884 	 of the diagnostic below but continue to use the original
3885 	 value and handle const folding later.  */
3886       const_tree cst_nelts = fold_non_dependent_expr (nelts, complain);
3887 
3888       /* The expression in a noptr-new-declarator is erroneous if it's of
3889 	 non-class type and its value before converting to std::size_t is
3890 	 less than zero. ... If the expression is a constant expression,
3891 	 the program is ill-fomed.  */
3892       if (TREE_CODE (cst_nelts) == INTEGER_CST
3893 	  && !valid_array_size_p (nelts_loc, cst_nelts, NULL_TREE,
3894 				  complain & tf_error))
3895 	return error_mark_node;
3896 
3897       nelts = mark_rvalue_use (nelts);
3898       nelts = cp_save_expr (cp_convert (sizetype, nelts, complain));
3899     }
3900 
3901   /* ``A reference cannot be created by the new operator.  A reference
3902      is not an object (8.2.2, 8.4.3), so a pointer to it could not be
3903      returned by new.'' ARM 5.3.3 */
3904   if (TYPE_REF_P (type))
3905     {
3906       if (complain & tf_error)
3907         error_at (loc, "new cannot be applied to a reference type");
3908       else
3909         return error_mark_node;
3910       type = TREE_TYPE (type);
3911     }
3912 
3913   if (TREE_CODE (type) == FUNCTION_TYPE)
3914     {
3915       if (complain & tf_error)
3916         error_at (loc, "new cannot be applied to a function type");
3917       return error_mark_node;
3918     }
3919 
3920   /* The type allocated must be complete.  If the new-type-id was
3921      "T[N]" then we are just checking that "T" is complete here, but
3922      that is equivalent, since the value of "N" doesn't matter.  */
3923   if (!complete_type_or_maybe_complain (type, NULL_TREE, complain))
3924     return error_mark_node;
3925 
3926   rval = build_new_1 (placement, type, nelts, init, use_global_new, complain);
3927   if (rval == error_mark_node)
3928     return error_mark_node;
3929 
3930   if (processing_template_decl)
3931     {
3932       tree ret = build_raw_new_expr (loc, orig_placement, type, orig_nelts,
3933 				     orig_init, use_global_new);
3934       release_tree_vector (orig_placement);
3935       release_tree_vector (orig_init);
3936       return ret;
3937     }
3938 
3939   /* Wrap it in a NOP_EXPR so warn_if_unused_value doesn't complain.  */
3940   rval = build1_loc (loc, NOP_EXPR, TREE_TYPE (rval), rval);
3941   TREE_NO_WARNING (rval) = 1;
3942 
3943   return rval;
3944 }
3945 
3946 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)3947 build_vec_delete_1 (location_t loc, tree base, tree maxindex, tree type,
3948 		    special_function_kind auto_delete_vec,
3949 		    int use_global_delete, tsubst_flags_t complain)
3950 {
3951   tree virtual_size;
3952   tree ptype = build_pointer_type (type = complete_type (type));
3953   tree size_exp;
3954 
3955   /* Temporary variables used by the loop.  */
3956   tree tbase, tbase_init;
3957 
3958   /* This is the body of the loop that implements the deletion of a
3959      single element, and moves temp variables to next elements.  */
3960   tree body;
3961 
3962   /* This is the LOOP_EXPR that governs the deletion of the elements.  */
3963   tree loop = 0;
3964 
3965   /* This is the thing that governs what to do after the loop has run.  */
3966   tree deallocate_expr = 0;
3967 
3968   /* This is the BIND_EXPR which holds the outermost iterator of the
3969      loop.  It is convenient to set this variable up and test it before
3970      executing any other code in the loop.
3971      This is also the containing expression returned by this function.  */
3972   tree controller = NULL_TREE;
3973   tree tmp;
3974 
3975   /* We should only have 1-D arrays here.  */
3976   gcc_assert (TREE_CODE (type) != ARRAY_TYPE);
3977 
3978   if (base == error_mark_node || maxindex == error_mark_node)
3979     return error_mark_node;
3980 
3981   if (!verify_type_context (loc, TCTX_DEALLOCATION, type,
3982 			    !(complain & tf_error)))
3983     return error_mark_node;
3984 
3985   if (!COMPLETE_TYPE_P (type))
3986     {
3987       if (complain & tf_warning)
3988 	{
3989 	  auto_diagnostic_group d;
3990 	  if (warning_at (loc, OPT_Wdelete_incomplete,
3991 			  "possible problem detected in invocation of "
3992 			  "operator %<delete []%>"))
3993 	    {
3994 	      cxx_incomplete_type_diagnostic (base, type, DK_WARNING);
3995 	      inform (loc, "neither the destructor nor the "
3996 		      "class-specific operator %<delete []%> will be called, "
3997 		      "even if they are declared when the class is defined");
3998 	    }
3999 	}
4000       /* This size won't actually be used.  */
4001       size_exp = size_one_node;
4002       goto no_destructor;
4003     }
4004 
4005   size_exp = size_in_bytes (type);
4006 
4007   if (! MAYBE_CLASS_TYPE_P (type))
4008     goto no_destructor;
4009   else if (TYPE_HAS_TRIVIAL_DESTRUCTOR (type))
4010     {
4011       /* Make sure the destructor is callable.  */
4012       if (type_build_dtor_call (type))
4013 	{
4014 	  tmp = build_delete (loc, ptype, base, sfk_complete_destructor,
4015 			      LOOKUP_NORMAL|LOOKUP_DESTRUCTOR, 1,
4016 			      complain);
4017 	  if (tmp == error_mark_node)
4018 	    return error_mark_node;
4019 	}
4020       goto no_destructor;
4021     }
4022 
4023   /* The below is short by the cookie size.  */
4024   virtual_size = size_binop (MULT_EXPR, size_exp,
4025 			     fold_convert (sizetype, maxindex));
4026 
4027   tbase = create_temporary_var (ptype);
4028   DECL_INITIAL (tbase)
4029     = fold_build_pointer_plus_loc (loc, fold_convert (ptype, base),
4030 				   virtual_size);
4031   tbase_init = build_stmt (loc, DECL_EXPR, tbase);
4032   controller = build3 (BIND_EXPR, void_type_node, tbase, NULL_TREE, NULL_TREE);
4033   TREE_SIDE_EFFECTS (controller) = 1;
4034 
4035   body = build1 (EXIT_EXPR, void_type_node,
4036 		 build2 (EQ_EXPR, boolean_type_node, tbase,
4037 			 fold_convert (ptype, base)));
4038   tmp = fold_build1_loc (loc, NEGATE_EXPR, sizetype, size_exp);
4039   tmp = fold_build_pointer_plus (tbase, tmp);
4040   tmp = cp_build_modify_expr (loc, tbase, NOP_EXPR, tmp, complain);
4041   if (tmp == error_mark_node)
4042     return error_mark_node;
4043   body = build_compound_expr (loc, body, tmp);
4044   tmp = build_delete (loc, ptype, tbase, sfk_complete_destructor,
4045 		      LOOKUP_NORMAL|LOOKUP_DESTRUCTOR, 1,
4046 		      complain);
4047   if (tmp == error_mark_node)
4048     return error_mark_node;
4049   body = build_compound_expr (loc, body, tmp);
4050 
4051   loop = build1 (LOOP_EXPR, void_type_node, body);
4052   loop = build_compound_expr (loc, tbase_init, loop);
4053 
4054  no_destructor:
4055   /* Delete the storage if appropriate.  */
4056   if (auto_delete_vec == sfk_deleting_destructor)
4057     {
4058       tree base_tbd;
4059 
4060       /* The below is short by the cookie size.  */
4061       virtual_size = size_binop (MULT_EXPR, size_exp,
4062 				 fold_convert (sizetype, maxindex));
4063 
4064       if (! TYPE_VEC_NEW_USES_COOKIE (type))
4065 	/* no header */
4066 	base_tbd = base;
4067       else
4068 	{
4069 	  tree cookie_size;
4070 
4071 	  cookie_size = targetm.cxx.get_cookie_size (type);
4072 	  base_tbd = cp_build_binary_op (loc,
4073 					 MINUS_EXPR,
4074 					 cp_convert (string_type_node,
4075 						     base, complain),
4076 					 cookie_size,
4077 					 complain);
4078 	  if (base_tbd == error_mark_node)
4079 	    return error_mark_node;
4080 	  base_tbd = cp_convert (ptype, base_tbd, complain);
4081 	  /* True size with header.  */
4082 	  virtual_size = size_binop (PLUS_EXPR, virtual_size, cookie_size);
4083 	}
4084 
4085       deallocate_expr = build_op_delete_call (VEC_DELETE_EXPR,
4086 					      base_tbd, virtual_size,
4087 					      use_global_delete & 1,
4088 					      /*placement=*/NULL_TREE,
4089 					      /*alloc_fn=*/NULL_TREE,
4090 					      complain);
4091 
4092       tree deallocate_call_expr = extract_call_expr (deallocate_expr);
4093       if (TREE_CODE (deallocate_call_expr) == CALL_EXPR)
4094 	CALL_FROM_NEW_OR_DELETE_P (deallocate_call_expr) = 1;
4095     }
4096 
4097   body = loop;
4098   if (!deallocate_expr)
4099     ;
4100   else if (!body)
4101     body = deallocate_expr;
4102   else
4103     /* The delete operator must be called, even if a destructor
4104        throws.  */
4105     body = build2 (TRY_FINALLY_EXPR, void_type_node, body, deallocate_expr);
4106 
4107   if (!body)
4108     body = integer_zero_node;
4109 
4110   /* Outermost wrapper: If pointer is null, punt.  */
4111   tree cond = build2_loc (loc, NE_EXPR, boolean_type_node, base,
4112 			  fold_convert (TREE_TYPE (base), nullptr_node));
4113   /* This is a compiler generated comparison, don't emit
4114      e.g. -Wnonnull-compare warning for it.  */
4115   TREE_NO_WARNING (cond) = 1;
4116   body = build3_loc (loc, COND_EXPR, void_type_node,
4117 		     cond, body, integer_zero_node);
4118   COND_EXPR_IS_VEC_DELETE (body) = true;
4119   body = build1 (NOP_EXPR, void_type_node, body);
4120 
4121   if (controller)
4122     {
4123       TREE_OPERAND (controller, 1) = body;
4124       body = controller;
4125     }
4126 
4127   if (TREE_CODE (base) == SAVE_EXPR)
4128     /* Pre-evaluate the SAVE_EXPR outside of the BIND_EXPR.  */
4129     body = build2 (COMPOUND_EXPR, void_type_node, base, body);
4130 
4131   return convert_to_void (body, ICV_CAST, complain);
4132 }
4133 
4134 /* Create an unnamed variable of the indicated TYPE.  */
4135 
4136 tree
create_temporary_var(tree type)4137 create_temporary_var (tree type)
4138 {
4139   tree decl;
4140 
4141   decl = build_decl (input_location,
4142 		     VAR_DECL, NULL_TREE, type);
4143   TREE_USED (decl) = 1;
4144   DECL_ARTIFICIAL (decl) = 1;
4145   DECL_IGNORED_P (decl) = 1;
4146   DECL_CONTEXT (decl) = current_function_decl;
4147 
4148   return decl;
4149 }
4150 
4151 /* Create a new temporary variable of the indicated TYPE, initialized
4152    to INIT.
4153 
4154    It is not entered into current_binding_level, because that breaks
4155    things when it comes time to do final cleanups (which take place
4156    "outside" the binding contour of the function).  */
4157 
4158 tree
get_temp_regvar(tree type,tree init)4159 get_temp_regvar (tree type, tree init)
4160 {
4161   tree decl;
4162 
4163   decl = create_temporary_var (type);
4164   add_decl_expr (decl);
4165 
4166   finish_expr_stmt (cp_build_modify_expr (input_location, decl, INIT_EXPR,
4167 					  init, tf_warning_or_error));
4168 
4169   return decl;
4170 }
4171 
4172 /* Subroutine of build_vec_init.  Returns true if assigning to an array of
4173    INNER_ELT_TYPE from INIT is trivial.  */
4174 
4175 static bool
vec_copy_assign_is_trivial(tree inner_elt_type,tree init)4176 vec_copy_assign_is_trivial (tree inner_elt_type, tree init)
4177 {
4178   tree fromtype = inner_elt_type;
4179   if (lvalue_p (init))
4180     fromtype = cp_build_reference_type (fromtype, /*rval*/false);
4181   return is_trivially_xible (MODIFY_EXPR, inner_elt_type, fromtype);
4182 }
4183 
4184 /* Subroutine of build_vec_init: Check that the array has at least N
4185    elements.  Other parameters are local variables in build_vec_init.  */
4186 
4187 void
finish_length_check(tree atype,tree iterator,tree obase,unsigned n)4188 finish_length_check (tree atype, tree iterator, tree obase, unsigned n)
4189 {
4190   tree nelts = build_int_cst (ptrdiff_type_node, n - 1);
4191   if (TREE_CODE (atype) != ARRAY_TYPE)
4192     {
4193       if (flag_exceptions)
4194 	{
4195 	  tree c = fold_build2 (LT_EXPR, boolean_type_node, iterator,
4196 				nelts);
4197 	  c = build3 (COND_EXPR, void_type_node, c,
4198 		      throw_bad_array_new_length (), void_node);
4199 	  finish_expr_stmt (c);
4200 	}
4201       /* Don't check an array new when -fno-exceptions.  */
4202     }
4203   else if (sanitize_flags_p (SANITIZE_BOUNDS)
4204 	   && current_function_decl != NULL_TREE)
4205     {
4206       /* Make sure the last element of the initializer is in bounds. */
4207       finish_expr_stmt
4208 	(ubsan_instrument_bounds
4209 	 (input_location, obase, &nelts, /*ignore_off_by_one*/false));
4210     }
4211 }
4212 
4213 /* `build_vec_init' returns tree structure that performs
4214    initialization of a vector of aggregate types.
4215 
4216    BASE is a reference to the vector, of ARRAY_TYPE, or a pointer
4217      to the first element, of POINTER_TYPE.
4218    MAXINDEX is the maximum index of the array (one less than the
4219      number of elements).  It is only used if BASE is a pointer or
4220      TYPE_DOMAIN (TREE_TYPE (BASE)) == NULL_TREE.
4221 
4222    INIT is the (possibly NULL) initializer.
4223 
4224    If EXPLICIT_VALUE_INIT_P is true, then INIT must be NULL.  All
4225    elements in the array are value-initialized.
4226 
4227    FROM_ARRAY is 0 if we should init everything with INIT
4228    (i.e., every element initialized from INIT).
4229    FROM_ARRAY is 1 if we should index into INIT in parallel
4230    with initialization of DECL.
4231    FROM_ARRAY is 2 if we should index into INIT in parallel,
4232    but use assignment instead of initialization.  */
4233 
4234 tree
build_vec_init(tree base,tree maxindex,tree init,bool explicit_value_init_p,int from_array,tsubst_flags_t complain)4235 build_vec_init (tree base, tree maxindex, tree init,
4236 		bool explicit_value_init_p,
4237 		int from_array, tsubst_flags_t complain)
4238 {
4239   tree rval;
4240   tree base2 = NULL_TREE;
4241   tree itype = NULL_TREE;
4242   tree iterator;
4243   /* The type of BASE.  */
4244   tree atype = TREE_TYPE (base);
4245   /* The type of an element in the array.  */
4246   tree type = TREE_TYPE (atype);
4247   /* The element type reached after removing all outer array
4248      types.  */
4249   tree inner_elt_type;
4250   /* The type of a pointer to an element in the array.  */
4251   tree ptype;
4252   tree stmt_expr;
4253   tree compound_stmt;
4254   int destroy_temps;
4255   tree try_block = NULL_TREE;
4256   HOST_WIDE_INT num_initialized_elts = 0;
4257   bool is_global;
4258   tree obase = base;
4259   bool xvalue = false;
4260   bool errors = false;
4261   location_t loc = (init ? cp_expr_loc_or_input_loc (init)
4262 		    : location_of (base));
4263 
4264   if (TREE_CODE (atype) == ARRAY_TYPE && TYPE_DOMAIN (atype))
4265     maxindex = array_type_nelts (atype);
4266 
4267   if (maxindex == NULL_TREE || maxindex == error_mark_node)
4268     return error_mark_node;
4269 
4270   maxindex = maybe_constant_value (maxindex);
4271   if (explicit_value_init_p)
4272     gcc_assert (!init);
4273 
4274   inner_elt_type = strip_array_types (type);
4275 
4276   /* Look through the TARGET_EXPR around a compound literal.  */
4277   if (init && TREE_CODE (init) == TARGET_EXPR
4278       && TREE_CODE (TARGET_EXPR_INITIAL (init)) == CONSTRUCTOR
4279       && from_array != 2)
4280     init = TARGET_EXPR_INITIAL (init);
4281 
4282   bool direct_init = false;
4283   if (from_array && init && BRACE_ENCLOSED_INITIALIZER_P (init)
4284       && CONSTRUCTOR_NELTS (init) == 1)
4285     {
4286       tree elt = CONSTRUCTOR_ELT (init, 0)->value;
4287       if (TREE_CODE (TREE_TYPE (elt)) == ARRAY_TYPE)
4288 	{
4289 	  direct_init = DIRECT_LIST_INIT_P (init);
4290 	  init = elt;
4291 	}
4292     }
4293 
4294   /* If we have a braced-init-list or string constant, make sure that the array
4295      is big enough for all the initializers.  */
4296   bool length_check = (init
4297 		       && (TREE_CODE (init) == STRING_CST
4298 			   || (TREE_CODE (init) == CONSTRUCTOR
4299 			       && CONSTRUCTOR_NELTS (init) > 0))
4300 		       && !TREE_CONSTANT (maxindex));
4301 
4302   if (init
4303       && TREE_CODE (atype) == ARRAY_TYPE
4304       && TREE_CONSTANT (maxindex)
4305       && (from_array == 2
4306 	  ? vec_copy_assign_is_trivial (inner_elt_type, init)
4307 	  : !TYPE_NEEDS_CONSTRUCTING (type))
4308       && ((TREE_CODE (init) == CONSTRUCTOR
4309 	   && (BRACE_ENCLOSED_INITIALIZER_P (init)
4310 	       || (same_type_ignoring_top_level_qualifiers_p
4311 		   (atype, TREE_TYPE (init))))
4312 	   /* Don't do this if the CONSTRUCTOR might contain something
4313 	      that might throw and require us to clean up.  */
4314 	   && (vec_safe_is_empty (CONSTRUCTOR_ELTS (init))
4315 	       || ! TYPE_HAS_NONTRIVIAL_DESTRUCTOR (inner_elt_type)))
4316 	  || from_array))
4317     {
4318       /* Do non-default initialization of trivial arrays resulting from
4319 	 brace-enclosed initializers.  In this case, digest_init and
4320 	 store_constructor will handle the semantics for us.  */
4321 
4322       if (BRACE_ENCLOSED_INITIALIZER_P (init))
4323 	init = digest_init (atype, init, complain);
4324       stmt_expr = build2 (INIT_EXPR, atype, base, init);
4325       return stmt_expr;
4326     }
4327 
4328   maxindex = cp_convert (ptrdiff_type_node, maxindex, complain);
4329   maxindex = fold_simple (maxindex);
4330 
4331   if (TREE_CODE (atype) == ARRAY_TYPE)
4332     {
4333       ptype = build_pointer_type (type);
4334       base = decay_conversion (base, complain);
4335       if (base == error_mark_node)
4336 	return error_mark_node;
4337       base = cp_convert (ptype, base, complain);
4338     }
4339   else
4340     ptype = atype;
4341 
4342   if (integer_all_onesp (maxindex))
4343     {
4344       /* Shortcut zero element case to avoid unneeded constructor synthesis.  */
4345       if (init && TREE_SIDE_EFFECTS (init))
4346 	base = build2 (COMPOUND_EXPR, ptype, init, base);
4347       return base;
4348     }
4349 
4350   /* The code we are generating looks like:
4351      ({
4352        T* t1 = (T*) base;
4353        T* rval = t1;
4354        ptrdiff_t iterator = maxindex;
4355        try {
4356 	 for (; iterator != -1; --iterator) {
4357 	   ... initialize *t1 ...
4358 	   ++t1;
4359 	 }
4360        } catch (...) {
4361 	 ... destroy elements that were constructed ...
4362        }
4363        rval;
4364      })
4365 
4366      We can omit the try and catch blocks if we know that the
4367      initialization will never throw an exception, or if the array
4368      elements do not have destructors.  We can omit the loop completely if
4369      the elements of the array do not have constructors.
4370 
4371      We actually wrap the entire body of the above in a STMT_EXPR, for
4372      tidiness.
4373 
4374      When copying from array to another, when the array elements have
4375      only trivial copy constructors, we should use __builtin_memcpy
4376      rather than generating a loop.  That way, we could take advantage
4377      of whatever cleverness the back end has for dealing with copies
4378      of blocks of memory.  */
4379 
4380   is_global = begin_init_stmts (&stmt_expr, &compound_stmt);
4381   destroy_temps = stmts_are_full_exprs_p ();
4382   current_stmt_tree ()->stmts_are_full_exprs_p = 0;
4383   rval = get_temp_regvar (ptype, base);
4384   base = get_temp_regvar (ptype, rval);
4385   iterator = get_temp_regvar (ptrdiff_type_node, maxindex);
4386 
4387   /* If initializing one array from another, initialize element by
4388      element.  We rely upon the below calls to do the argument
4389      checking.  Evaluate the initializer before entering the try block.  */
4390   if (from_array && init && TREE_CODE (init) != CONSTRUCTOR)
4391     {
4392       if (lvalue_kind (init) & clk_rvalueref)
4393 	xvalue = true;
4394       base2 = decay_conversion (init, complain);
4395       if (base2 == error_mark_node)
4396 	return error_mark_node;
4397       itype = TREE_TYPE (base2);
4398       base2 = get_temp_regvar (itype, base2);
4399       itype = TREE_TYPE (itype);
4400     }
4401 
4402   /* Protect the entire array initialization so that we can destroy
4403      the partially constructed array if an exception is thrown.
4404      But don't do this if we're assigning.  */
4405   if (flag_exceptions && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
4406       && from_array != 2)
4407     {
4408       try_block = begin_try_block ();
4409     }
4410 
4411   /* Should we try to create a constant initializer?  */
4412   bool try_const = (TREE_CODE (atype) == ARRAY_TYPE
4413 		    && TREE_CONSTANT (maxindex)
4414 		    && (init ? TREE_CODE (init) == CONSTRUCTOR
4415 			: (type_has_constexpr_default_constructor
4416 			   (inner_elt_type)))
4417 		    && (literal_type_p (inner_elt_type)
4418 			|| TYPE_HAS_CONSTEXPR_CTOR (inner_elt_type)));
4419   vec<constructor_elt, va_gc> *const_vec = NULL;
4420   bool saw_non_const = false;
4421   /* If we're initializing a static array, we want to do static
4422      initialization of any elements with constant initializers even if
4423      some are non-constant.  */
4424   bool do_static_init = (DECL_P (obase) && TREE_STATIC (obase));
4425 
4426   bool empty_list = false;
4427   if (init && BRACE_ENCLOSED_INITIALIZER_P (init)
4428       && CONSTRUCTOR_NELTS (init) == 0)
4429     /* Skip over the handling of non-empty init lists.  */
4430     empty_list = true;
4431 
4432   /* Maybe pull out constant value when from_array? */
4433 
4434   else if (init != NULL_TREE && TREE_CODE (init) == CONSTRUCTOR)
4435     {
4436       /* Do non-default initialization of non-trivial arrays resulting from
4437 	 brace-enclosed initializers.  */
4438       unsigned HOST_WIDE_INT idx;
4439       tree field, elt;
4440       /* If the constructor already has the array type, it's been through
4441 	 digest_init, so we shouldn't try to do anything more.  */
4442       bool digested = same_type_p (atype, TREE_TYPE (init));
4443       from_array = 0;
4444 
4445       if (length_check)
4446 	finish_length_check (atype, iterator, obase, CONSTRUCTOR_NELTS (init));
4447 
4448       if (try_const)
4449 	vec_alloc (const_vec, CONSTRUCTOR_NELTS (init));
4450 
4451       FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init), idx, field, elt)
4452 	{
4453 	  tree baseref = build1 (INDIRECT_REF, type, base);
4454 	  tree one_init;
4455 
4456 	  num_initialized_elts++;
4457 
4458 	  current_stmt_tree ()->stmts_are_full_exprs_p = 1;
4459 	  if (digested)
4460 	    one_init = build2 (INIT_EXPR, type, baseref, elt);
4461 	  else if (MAYBE_CLASS_TYPE_P (type) || TREE_CODE (type) == ARRAY_TYPE)
4462 	    one_init = build_aggr_init (baseref, elt, 0, complain);
4463 	  else
4464 	    one_init = cp_build_modify_expr (input_location, baseref,
4465 					     NOP_EXPR, elt, complain);
4466 	  if (one_init == error_mark_node)
4467 	    errors = true;
4468 	  if (try_const)
4469 	    {
4470 	      if (!field)
4471 		field = size_int (idx);
4472 	      tree e = maybe_constant_init (one_init);
4473 	      if (reduced_constant_expression_p (e))
4474 		{
4475 		  CONSTRUCTOR_APPEND_ELT (const_vec, field, e);
4476 		  if (do_static_init)
4477 		    one_init = NULL_TREE;
4478 		  else
4479 		    one_init = build2 (INIT_EXPR, type, baseref, e);
4480 		}
4481 	      else
4482 		{
4483 		  if (do_static_init)
4484 		    {
4485 		      tree value = build_zero_init (TREE_TYPE (e), NULL_TREE,
4486 						    true);
4487 		      if (value)
4488 			CONSTRUCTOR_APPEND_ELT (const_vec, field, value);
4489 		    }
4490 		  saw_non_const = true;
4491 		}
4492 	    }
4493 
4494 	  if (one_init)
4495 	    finish_expr_stmt (one_init);
4496 	  current_stmt_tree ()->stmts_are_full_exprs_p = 0;
4497 
4498 	  one_init = cp_build_unary_op (PREINCREMENT_EXPR, base, false,
4499 					complain);
4500 	  if (one_init == error_mark_node)
4501 	    errors = true;
4502 	  else
4503 	    finish_expr_stmt (one_init);
4504 
4505 	  one_init = cp_build_unary_op (PREDECREMENT_EXPR, iterator, false,
4506 					complain);
4507 	  if (one_init == error_mark_node)
4508 	    errors = true;
4509 	  else
4510 	    finish_expr_stmt (one_init);
4511 	}
4512 
4513       /* Any elements without explicit initializers get T{}.  */
4514       empty_list = true;
4515     }
4516   else if (init && TREE_CODE (init) == STRING_CST)
4517     {
4518       /* Check that the array is at least as long as the string.  */
4519       if (length_check)
4520 	finish_length_check (atype, iterator, obase,
4521 			     TREE_STRING_LENGTH (init));
4522       tree length = build_int_cst (ptrdiff_type_node,
4523 				   TREE_STRING_LENGTH (init));
4524 
4525       /* Copy the string to the first part of the array.  */
4526       tree alias_set = build_int_cst (build_pointer_type (type), 0);
4527       tree lhs = build2 (MEM_REF, TREE_TYPE (init), base, alias_set);
4528       tree stmt = build2 (MODIFY_EXPR, void_type_node, lhs, init);
4529       finish_expr_stmt (stmt);
4530 
4531       /* Adjust the counter and pointer.  */
4532       stmt = cp_build_binary_op (loc, MINUS_EXPR, iterator, length, complain);
4533       stmt = build2 (MODIFY_EXPR, void_type_node, iterator, stmt);
4534       finish_expr_stmt (stmt);
4535 
4536       stmt = cp_build_binary_op (loc, PLUS_EXPR, base, length, complain);
4537       stmt = build2 (MODIFY_EXPR, void_type_node, base, stmt);
4538       finish_expr_stmt (stmt);
4539 
4540       /* And set the rest of the array to NUL.  */
4541       from_array = 0;
4542       explicit_value_init_p = true;
4543     }
4544   else if (from_array)
4545     {
4546       if (init)
4547 	/* OK, we set base2 above.  */;
4548       else if (CLASS_TYPE_P (type)
4549 	       && ! TYPE_HAS_DEFAULT_CONSTRUCTOR (type))
4550 	{
4551           if (complain & tf_error)
4552             error ("initializer ends prematurely");
4553 	  errors = true;
4554 	}
4555     }
4556 
4557   /* Now, default-initialize any remaining elements.  We don't need to
4558      do that if a) the type does not need constructing, or b) we've
4559      already initialized all the elements.
4560 
4561      We do need to keep going if we're copying an array.  */
4562 
4563   if (try_const && !init)
4564     /* With a constexpr default constructor, which we checked for when
4565        setting try_const above, default-initialization is equivalent to
4566        value-initialization, and build_value_init gives us something more
4567        friendly to maybe_constant_init.  */
4568     explicit_value_init_p = true;
4569   if (from_array
4570       || ((type_build_ctor_call (type) || init || explicit_value_init_p)
4571 	  && ! (tree_fits_shwi_p (maxindex)
4572 		&& (num_initialized_elts
4573 		    == tree_to_shwi (maxindex) + 1))))
4574     {
4575       /* If the ITERATOR is lesser or equal to -1, then we don't have to loop;
4576 	 we've already initialized all the elements.  */
4577       tree for_stmt;
4578       tree elt_init;
4579       tree to;
4580 
4581       for_stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
4582       finish_init_stmt (for_stmt);
4583       finish_for_cond (build2 (GT_EXPR, boolean_type_node, iterator,
4584 			       build_int_cst (TREE_TYPE (iterator), -1)),
4585 		       for_stmt, false, 0);
4586       elt_init = cp_build_unary_op (PREDECREMENT_EXPR, iterator, false,
4587 				    complain);
4588       if (elt_init == error_mark_node)
4589 	errors = true;
4590       finish_for_expr (elt_init, for_stmt);
4591 
4592       to = build1 (INDIRECT_REF, type, base);
4593 
4594       /* If the initializer is {}, then all elements are initialized from T{}.
4595 	 But for non-classes, that's the same as value-initialization.  */
4596       if (empty_list)
4597 	{
4598 	  if (cxx_dialect >= cxx11 && AGGREGATE_TYPE_P (type))
4599 	    {
4600 	      init = build_constructor (init_list_type_node, NULL);
4601 	    }
4602 	  else
4603 	    {
4604 	      init = NULL_TREE;
4605 	      explicit_value_init_p = true;
4606 	    }
4607 	}
4608 
4609       if (from_array)
4610 	{
4611 	  tree from;
4612 
4613 	  if (base2)
4614 	    {
4615 	      from = build1 (INDIRECT_REF, itype, base2);
4616 	      if (xvalue)
4617 		from = move (from);
4618 	      if (direct_init)
4619 		from = build_tree_list (NULL_TREE, from);
4620 	    }
4621 	  else
4622 	    from = NULL_TREE;
4623 
4624 	  if (TREE_CODE (type) == ARRAY_TYPE)
4625 	    elt_init = build_vec_init (to, NULL_TREE, from, /*val_init*/false,
4626 				       from_array, complain);
4627 	  else if (from_array == 2)
4628 	    elt_init = cp_build_modify_expr (input_location, to, NOP_EXPR,
4629 					     from, complain);
4630 	  else if (type_build_ctor_call (type))
4631 	    elt_init = build_aggr_init (to, from, 0, complain);
4632 	  else if (from)
4633 	    elt_init = cp_build_modify_expr (input_location, to, NOP_EXPR, from,
4634 					     complain);
4635 	  else
4636 	    gcc_unreachable ();
4637 	}
4638       else if (TREE_CODE (type) == ARRAY_TYPE)
4639 	{
4640 	  if (init && !BRACE_ENCLOSED_INITIALIZER_P (init))
4641 	    {
4642 	      if ((complain & tf_error))
4643 		error_at (loc, "array must be initialized "
4644 			  "with a brace-enclosed initializer");
4645 	      elt_init = error_mark_node;
4646 	    }
4647 	  else
4648 	    elt_init = build_vec_init (build1 (INDIRECT_REF, type, base),
4649 				       0, init,
4650 				       explicit_value_init_p,
4651 				       0, complain);
4652 	}
4653       else if (explicit_value_init_p)
4654 	{
4655 	  elt_init = build_value_init (type, complain);
4656 	  if (elt_init != error_mark_node)
4657 	    elt_init = build2 (INIT_EXPR, type, to, elt_init);
4658 	}
4659       else
4660 	{
4661 	  gcc_assert (type_build_ctor_call (type) || init);
4662 	  if (CLASS_TYPE_P (type))
4663 	    elt_init = build_aggr_init (to, init, 0, complain);
4664 	  else
4665 	    {
4666 	      if (TREE_CODE (init) == TREE_LIST)
4667 		init = build_x_compound_expr_from_list (init, ELK_INIT,
4668 							complain);
4669 	      elt_init = (init == error_mark_node
4670 			  ? error_mark_node
4671 			  : build2 (INIT_EXPR, type, to, init));
4672 	    }
4673 	}
4674 
4675       if (elt_init == error_mark_node)
4676 	errors = true;
4677 
4678       if (try_const)
4679 	{
4680 	  /* FIXME refs to earlier elts */
4681 	  tree e = maybe_constant_init (elt_init);
4682 	  if (reduced_constant_expression_p (e))
4683 	    {
4684 	      if (initializer_zerop (e))
4685 		/* Don't fill the CONSTRUCTOR with zeros.  */
4686 		e = NULL_TREE;
4687 	      if (do_static_init)
4688 		elt_init = NULL_TREE;
4689 	    }
4690 	  else
4691 	    {
4692 	      saw_non_const = true;
4693 	      if (do_static_init)
4694 		e = build_zero_init (TREE_TYPE (e), NULL_TREE, true);
4695 	      else
4696 		e = NULL_TREE;
4697 	    }
4698 
4699 	  if (e)
4700 	    {
4701 	      HOST_WIDE_INT last = tree_to_shwi (maxindex);
4702 	      if (num_initialized_elts <= last)
4703 		{
4704 		  tree field = size_int (num_initialized_elts);
4705 		  if (num_initialized_elts != last)
4706 		    field = build2 (RANGE_EXPR, sizetype, field,
4707 				    size_int (last));
4708 		  CONSTRUCTOR_APPEND_ELT (const_vec, field, e);
4709 		}
4710 	    }
4711 	}
4712 
4713       current_stmt_tree ()->stmts_are_full_exprs_p = 1;
4714       if (elt_init && !errors)
4715 	finish_expr_stmt (elt_init);
4716       current_stmt_tree ()->stmts_are_full_exprs_p = 0;
4717 
4718       finish_expr_stmt (cp_build_unary_op (PREINCREMENT_EXPR, base, false,
4719                                            complain));
4720       if (base2)
4721 	finish_expr_stmt (cp_build_unary_op (PREINCREMENT_EXPR, base2, false,
4722                                              complain));
4723 
4724       finish_for_stmt (for_stmt);
4725     }
4726 
4727   /* Make sure to cleanup any partially constructed elements.  */
4728   if (flag_exceptions && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
4729       && from_array != 2)
4730     {
4731       tree e;
4732       tree m = cp_build_binary_op (input_location,
4733 				   MINUS_EXPR, maxindex, iterator,
4734 				   complain);
4735 
4736       /* Flatten multi-dimensional array since build_vec_delete only
4737 	 expects one-dimensional array.  */
4738       if (TREE_CODE (type) == ARRAY_TYPE)
4739 	m = cp_build_binary_op (input_location,
4740 				MULT_EXPR, m,
4741 				/* Avoid mixing signed and unsigned.  */
4742 				convert (TREE_TYPE (m),
4743 					 array_type_nelts_total (type)),
4744 				complain);
4745 
4746       finish_cleanup_try_block (try_block);
4747       e = build_vec_delete_1 (input_location, rval, m,
4748 			      inner_elt_type, sfk_complete_destructor,
4749 			      /*use_global_delete=*/0, complain);
4750       if (e == error_mark_node)
4751 	errors = true;
4752       finish_cleanup (e, try_block);
4753     }
4754 
4755   /* The value of the array initialization is the array itself, RVAL
4756      is a pointer to the first element.  */
4757   finish_stmt_expr_expr (rval, stmt_expr);
4758 
4759   stmt_expr = finish_init_stmts (is_global, stmt_expr, compound_stmt);
4760 
4761   current_stmt_tree ()->stmts_are_full_exprs_p = destroy_temps;
4762 
4763   if (errors)
4764     return error_mark_node;
4765 
4766   if (try_const)
4767     {
4768       if (!saw_non_const)
4769 	{
4770 	  tree const_init = build_constructor (atype, const_vec);
4771 	  return build2 (INIT_EXPR, atype, obase, const_init);
4772 	}
4773       else if (do_static_init && !vec_safe_is_empty (const_vec))
4774 	DECL_INITIAL (obase) = build_constructor (atype, const_vec);
4775       else
4776 	vec_free (const_vec);
4777     }
4778 
4779   /* Now make the result have the correct type.  */
4780   if (TREE_CODE (atype) == ARRAY_TYPE)
4781     {
4782       atype = build_pointer_type (atype);
4783       stmt_expr = build1 (NOP_EXPR, atype, stmt_expr);
4784       stmt_expr = cp_build_fold_indirect_ref (stmt_expr);
4785       TREE_NO_WARNING (stmt_expr) = 1;
4786     }
4787 
4788   return stmt_expr;
4789 }
4790 
4791 /* Call the DTOR_KIND destructor for EXP.  FLAGS are as for
4792    build_delete.  */
4793 
4794 static tree
build_dtor_call(tree exp,special_function_kind dtor_kind,int flags,tsubst_flags_t complain)4795 build_dtor_call (tree exp, special_function_kind dtor_kind, int flags,
4796 		 tsubst_flags_t complain)
4797 {
4798   tree name;
4799   switch (dtor_kind)
4800     {
4801     case sfk_complete_destructor:
4802       name = complete_dtor_identifier;
4803       break;
4804 
4805     case sfk_base_destructor:
4806       name = base_dtor_identifier;
4807       break;
4808 
4809     case sfk_deleting_destructor:
4810       name = deleting_dtor_identifier;
4811       break;
4812 
4813     default:
4814       gcc_unreachable ();
4815     }
4816 
4817   return build_special_member_call (exp, name,
4818 				    /*args=*/NULL,
4819 				    /*binfo=*/TREE_TYPE (exp),
4820 				    flags,
4821 				    complain);
4822 }
4823 
4824 /* Generate a call to a destructor. TYPE is the type to cast ADDR to.
4825    ADDR is an expression which yields the store to be destroyed.
4826    AUTO_DELETE is the name of the destructor to call, i.e., either
4827    sfk_complete_destructor, sfk_base_destructor, or
4828    sfk_deleting_destructor.
4829 
4830    FLAGS is the logical disjunction of zero or more LOOKUP_
4831    flags.  See cp-tree.h for more info.  */
4832 
4833 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)4834 build_delete (location_t loc, tree otype, tree addr,
4835 	      special_function_kind auto_delete,
4836 	      int flags, int use_global_delete, tsubst_flags_t complain)
4837 {
4838   tree expr;
4839 
4840   if (addr == error_mark_node)
4841     return error_mark_node;
4842 
4843   tree type = TYPE_MAIN_VARIANT (otype);
4844 
4845   /* Can happen when CURRENT_EXCEPTION_OBJECT gets its type
4846      set to `error_mark_node' before it gets properly cleaned up.  */
4847   if (type == error_mark_node)
4848     return error_mark_node;
4849 
4850   if (TYPE_PTR_P (type))
4851     type = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4852 
4853   if (TREE_CODE (type) == ARRAY_TYPE)
4854     {
4855       if (TYPE_DOMAIN (type) == NULL_TREE)
4856 	{
4857 	  if (complain & tf_error)
4858 	    error_at (loc, "unknown array size in delete");
4859 	  return error_mark_node;
4860 	}
4861       return build_vec_delete (loc, addr, array_type_nelts (type),
4862 			       auto_delete, use_global_delete, complain);
4863     }
4864 
4865   bool deleting = (auto_delete == sfk_deleting_destructor);
4866   gcc_assert (deleting == !(flags & LOOKUP_DESTRUCTOR));
4867 
4868   if (TYPE_PTR_P (otype))
4869     {
4870       addr = mark_rvalue_use (addr);
4871 
4872       /* We don't want to warn about delete of void*, only other
4873 	  incomplete types.  Deleting other incomplete types
4874 	  invokes undefined behavior, but it is not ill-formed, so
4875 	  compile to something that would even do The Right Thing
4876 	  (TM) should the type have a trivial dtor and no delete
4877 	  operator.  */
4878       if (!VOID_TYPE_P (type))
4879 	{
4880 	  complete_type (type);
4881 	  if (deleting
4882 	      && !verify_type_context (loc, TCTX_DEALLOCATION, type,
4883 				       !(complain & tf_error)))
4884 	    return error_mark_node;
4885 
4886 	  if (!COMPLETE_TYPE_P (type))
4887 	    {
4888 	      if (complain & tf_warning)
4889 		{
4890 		  auto_diagnostic_group d;
4891 		  if (warning_at (loc, OPT_Wdelete_incomplete,
4892 				  "possible problem detected in invocation of "
4893 				  "%<operator delete%>"))
4894 		    {
4895 		      cxx_incomplete_type_diagnostic (addr, type, DK_WARNING);
4896 		      inform (loc,
4897 			      "neither the destructor nor the class-specific "
4898 			      "%<operator delete%> will be called, even if "
4899 			      "they are declared when the class is defined");
4900 		    }
4901 		}
4902 	    }
4903 	  else if (deleting && warn_delnonvdtor
4904 	           && MAYBE_CLASS_TYPE_P (type) && !CLASSTYPE_FINAL (type)
4905 		   && TYPE_POLYMORPHIC_P (type))
4906 	    {
4907 	      tree dtor = CLASSTYPE_DESTRUCTOR (type);
4908 	      if (!dtor || !DECL_VINDEX (dtor))
4909 		{
4910 		  if (CLASSTYPE_PURE_VIRTUALS (type))
4911 		    warning_at (loc, OPT_Wdelete_non_virtual_dtor,
4912 				"deleting object of abstract class type %qT"
4913 				" which has non-virtual destructor"
4914 				" will cause undefined behavior", type);
4915 		  else
4916 		    warning_at (loc, OPT_Wdelete_non_virtual_dtor,
4917 				"deleting object of polymorphic class type %qT"
4918 				" which has non-virtual destructor"
4919 				" might cause undefined behavior", type);
4920 		}
4921 	    }
4922 	}
4923 
4924       /* Throw away const and volatile on target type of addr.  */
4925       addr = convert_force (build_pointer_type (type), addr, 0, complain);
4926     }
4927   else
4928     {
4929       /* Don't check PROTECT here; leave that decision to the
4930 	 destructor.  If the destructor is accessible, call it,
4931 	 else report error.  */
4932       addr = cp_build_addr_expr (addr, complain);
4933       if (addr == error_mark_node)
4934 	return error_mark_node;
4935 
4936       addr = convert_force (build_pointer_type (type), addr, 0, complain);
4937     }
4938 
4939   if (deleting)
4940     /* We will use ADDR multiple times so we must save it.  */
4941     addr = save_expr (addr);
4942 
4943   bool virtual_p = false;
4944   if (type_build_dtor_call (type))
4945     {
4946       if (CLASSTYPE_LAZY_DESTRUCTOR (type))
4947 	lazily_declare_fn (sfk_destructor, type);
4948       virtual_p = DECL_VIRTUAL_P (CLASSTYPE_DESTRUCTOR (type));
4949     }
4950 
4951   tree head = NULL_TREE;
4952   tree do_delete = NULL_TREE;
4953   bool destroying_delete = false;
4954 
4955   if (!deleting)
4956     {
4957       /* Leave do_delete null.  */
4958     }
4959   /* For `::delete x', we must not use the deleting destructor
4960      since then we would not be sure to get the global `operator
4961      delete'.  */
4962   else if (use_global_delete)
4963     {
4964       head = get_target_expr (build_headof (addr));
4965       /* Delete the object.  */
4966       do_delete = build_op_delete_call (DELETE_EXPR,
4967 					head,
4968 					cxx_sizeof_nowarn (type),
4969 					/*global_p=*/true,
4970 					/*placement=*/NULL_TREE,
4971 					/*alloc_fn=*/NULL_TREE,
4972 					complain);
4973       /* Otherwise, treat this like a complete object destructor
4974 	 call.  */
4975       auto_delete = sfk_complete_destructor;
4976     }
4977   /* If the destructor is non-virtual, there is no deleting
4978      variant.  Instead, we must explicitly call the appropriate
4979      `operator delete' here.  */
4980   else if (!virtual_p)
4981     {
4982       /* Build the call.  */
4983       do_delete = build_op_delete_call (DELETE_EXPR,
4984 					addr,
4985 					cxx_sizeof_nowarn (type),
4986 					/*global_p=*/false,
4987 					/*placement=*/NULL_TREE,
4988 					/*alloc_fn=*/NULL_TREE,
4989 					complain);
4990       /* Call the complete object destructor.  */
4991       auto_delete = sfk_complete_destructor;
4992       if (do_delete != error_mark_node)
4993 	{
4994 	  tree fn = get_callee_fndecl (do_delete);
4995 	  destroying_delete = destroying_delete_p (fn);
4996 	}
4997     }
4998   else if (TYPE_GETS_REG_DELETE (type))
4999     {
5000       /* Make sure we have access to the member op delete, even though
5001 	 we'll actually be calling it from the destructor.  */
5002       build_op_delete_call (DELETE_EXPR, addr, cxx_sizeof_nowarn (type),
5003 			    /*global_p=*/false,
5004 			    /*placement=*/NULL_TREE,
5005 			    /*alloc_fn=*/NULL_TREE,
5006 			    complain);
5007     }
5008 
5009   if (!destroying_delete && type_build_dtor_call (type))
5010     expr = build_dtor_call (cp_build_fold_indirect_ref (addr),
5011 			    auto_delete, flags, complain);
5012   else
5013     expr = build_trivial_dtor_call (addr);
5014   if (expr == error_mark_node)
5015     return error_mark_node;
5016 
5017   if (!deleting)
5018     {
5019       protected_set_expr_location (expr, loc);
5020       return expr;
5021     }
5022 
5023   if (do_delete)
5024     {
5025       tree do_delete_call_expr = extract_call_expr (do_delete);
5026       if (TREE_CODE (do_delete_call_expr) == CALL_EXPR)
5027 	CALL_FROM_NEW_OR_DELETE_P (do_delete_call_expr) = 1;
5028     }
5029 
5030   if (do_delete && !TREE_SIDE_EFFECTS (expr))
5031     expr = do_delete;
5032   else if (do_delete)
5033     /* The delete operator must be called, regardless of whether
5034        the destructor throws.
5035 
5036        [expr.delete]/7 The deallocation function is called
5037        regardless of whether the destructor for the object or some
5038        element of the array throws an exception.  */
5039     expr = build2 (TRY_FINALLY_EXPR, void_type_node, expr, do_delete);
5040 
5041   /* We need to calculate this before the dtor changes the vptr.  */
5042   if (head)
5043     expr = build2 (COMPOUND_EXPR, void_type_node, head, expr);
5044 
5045   /* Handle deleting a null pointer.  */
5046   warning_sentinel s (warn_address);
5047   tree ifexp = cp_build_binary_op (loc, NE_EXPR, addr,
5048 				   nullptr_node, complain);
5049   ifexp = cp_fully_fold (ifexp);
5050 
5051   if (ifexp == error_mark_node)
5052     return error_mark_node;
5053   /* This is a compiler generated comparison, don't emit
5054      e.g. -Wnonnull-compare warning for it.  */
5055   else if (TREE_CODE (ifexp) == NE_EXPR)
5056     TREE_NO_WARNING (ifexp) = 1;
5057 
5058   if (!integer_nonzerop (ifexp))
5059     expr = build3 (COND_EXPR, void_type_node, ifexp, expr, void_node);
5060 
5061   protected_set_expr_location (expr, loc);
5062   return expr;
5063 }
5064 
5065 /* At the beginning of a destructor, push cleanups that will call the
5066    destructors for our base classes and members.
5067 
5068    Called from begin_destructor_body.  */
5069 
5070 void
push_base_cleanups(void)5071 push_base_cleanups (void)
5072 {
5073   tree binfo, base_binfo;
5074   int i;
5075   tree member;
5076   tree expr;
5077   vec<tree, va_gc> *vbases;
5078 
5079   /* Run destructors for all virtual baseclasses.  */
5080   if (!ABSTRACT_CLASS_TYPE_P (current_class_type)
5081       && CLASSTYPE_VBASECLASSES (current_class_type))
5082     {
5083       tree cond = (condition_conversion
5084 		   (build2 (BIT_AND_EXPR, integer_type_node,
5085 			    current_in_charge_parm,
5086 			    integer_two_node)));
5087 
5088       /* The CLASSTYPE_VBASECLASSES vector is in initialization
5089 	 order, which is also the right order for pushing cleanups.  */
5090       for (vbases = CLASSTYPE_VBASECLASSES (current_class_type), i = 0;
5091 	   vec_safe_iterate (vbases, i, &base_binfo); i++)
5092 	{
5093 	  if (type_build_dtor_call (BINFO_TYPE (base_binfo)))
5094 	    {
5095 	      expr = build_special_member_call (current_class_ref,
5096 						base_dtor_identifier,
5097 						NULL,
5098 						base_binfo,
5099 						(LOOKUP_NORMAL
5100 						 | LOOKUP_NONVIRTUAL),
5101 						tf_warning_or_error);
5102 	      if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (BINFO_TYPE (base_binfo)))
5103 		{
5104 		  expr = build3 (COND_EXPR, void_type_node, cond,
5105 				 expr, void_node);
5106 		  finish_decl_cleanup (NULL_TREE, expr);
5107 		}
5108 	    }
5109 	}
5110     }
5111 
5112   /* Take care of the remaining baseclasses.  */
5113   for (binfo = TYPE_BINFO (current_class_type), i = 0;
5114        BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
5115     {
5116       if (BINFO_VIRTUAL_P (base_binfo)
5117 	  || !type_build_dtor_call (BINFO_TYPE (base_binfo)))
5118 	continue;
5119 
5120       expr = build_special_member_call (current_class_ref,
5121 					base_dtor_identifier,
5122 					NULL, base_binfo,
5123 					LOOKUP_NORMAL | LOOKUP_NONVIRTUAL,
5124                                         tf_warning_or_error);
5125       if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (BINFO_TYPE (base_binfo)))
5126 	finish_decl_cleanup (NULL_TREE, expr);
5127     }
5128 
5129   /* Don't automatically destroy union members.  */
5130   if (TREE_CODE (current_class_type) == UNION_TYPE)
5131     return;
5132 
5133   for (member = TYPE_FIELDS (current_class_type); member;
5134        member = DECL_CHAIN (member))
5135     {
5136       tree this_type = TREE_TYPE (member);
5137       if (this_type == error_mark_node
5138 	  || TREE_CODE (member) != FIELD_DECL
5139 	  || DECL_ARTIFICIAL (member))
5140 	continue;
5141       if (ANON_AGGR_TYPE_P (this_type))
5142 	continue;
5143       if (type_build_dtor_call (this_type))
5144 	{
5145 	  tree this_member = (build_class_member_access_expr
5146 			      (current_class_ref, member,
5147 			       /*access_path=*/NULL_TREE,
5148 			       /*preserve_reference=*/false,
5149 			       tf_warning_or_error));
5150 	  expr = build_delete (input_location, this_type, this_member,
5151 			       sfk_complete_destructor,
5152 			       LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR|LOOKUP_NORMAL,
5153 			       0, tf_warning_or_error);
5154 	  if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (this_type))
5155 	    finish_decl_cleanup (NULL_TREE, expr);
5156 	}
5157     }
5158 }
5159 
5160 /* Build a C++ vector delete expression.
5161    MAXINDEX is the number of elements to be deleted.
5162    ELT_SIZE is the nominal size of each element in the vector.
5163    BASE is the expression that should yield the store to be deleted.
5164    This function expands (or synthesizes) these calls itself.
5165    AUTO_DELETE_VEC says whether the container (vector) should be deallocated.
5166 
5167    This also calls delete for virtual baseclasses of elements of the vector.
5168 
5169    Update: MAXINDEX is no longer needed.  The size can be extracted from the
5170    start of the vector for pointers, and from the type for arrays.  We still
5171    use MAXINDEX for arrays because it happens to already have one of the
5172    values we'd have to extract.  (We could use MAXINDEX with pointers to
5173    confirm the size, and trap if the numbers differ; not clear that it'd
5174    be worth bothering.)  */
5175 
5176 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)5177 build_vec_delete (location_t loc, tree base, tree maxindex,
5178 		  special_function_kind auto_delete_vec,
5179 		  int use_global_delete, tsubst_flags_t complain)
5180 {
5181   tree type;
5182   tree rval;
5183   tree base_init = NULL_TREE;
5184 
5185   type = TREE_TYPE (base);
5186 
5187   if (TYPE_PTR_P (type))
5188     {
5189       /* Step back one from start of vector, and read dimension.  */
5190       tree cookie_addr;
5191       tree size_ptr_type = build_pointer_type (sizetype);
5192 
5193       base = mark_rvalue_use (base);
5194       if (TREE_SIDE_EFFECTS (base))
5195 	{
5196 	  base_init = get_target_expr (base);
5197 	  base = TARGET_EXPR_SLOT (base_init);
5198 	}
5199       type = strip_array_types (TREE_TYPE (type));
5200       cookie_addr = fold_build1_loc (loc, NEGATE_EXPR,
5201 				 sizetype, TYPE_SIZE_UNIT (sizetype));
5202       cookie_addr = fold_build_pointer_plus (fold_convert (size_ptr_type, base),
5203 					     cookie_addr);
5204       maxindex = cp_build_fold_indirect_ref (cookie_addr);
5205     }
5206   else if (TREE_CODE (type) == ARRAY_TYPE)
5207     {
5208       /* Get the total number of things in the array, maxindex is a
5209 	 bad name.  */
5210       maxindex = array_type_nelts_total (type);
5211       type = strip_array_types (type);
5212       base = decay_conversion (base, complain);
5213       if (base == error_mark_node)
5214 	return error_mark_node;
5215       if (TREE_SIDE_EFFECTS (base))
5216 	{
5217 	  base_init = get_target_expr (base);
5218 	  base = TARGET_EXPR_SLOT (base_init);
5219 	}
5220     }
5221   else
5222     {
5223       if (base != error_mark_node && !(complain & tf_error))
5224 	error_at (loc,
5225 		  "type to vector delete is neither pointer or array type");
5226       return error_mark_node;
5227     }
5228 
5229   rval = build_vec_delete_1 (loc, base, maxindex, type, auto_delete_vec,
5230 			     use_global_delete, complain);
5231   if (base_init && rval != error_mark_node)
5232     rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), base_init, rval);
5233 
5234   protected_set_expr_location (rval, loc);
5235   return rval;
5236 }
5237 
5238 #include "gt-cp-init.h"
5239