1 /* Handle initialization things in C++.
2    Copyright (C) 1987-2019 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 
37 static bool begin_init_stmts (tree *, tree *);
38 static tree finish_init_stmts (bool, tree, tree);
39 static void construct_virtual_base (tree, tree);
40 static void expand_aggr_init_1 (tree, tree, tree, tree, int, tsubst_flags_t);
41 static void expand_default_init (tree, tree, tree, tree, int, tsubst_flags_t);
42 static void perform_member_init (tree, tree);
43 static int member_init_ok_or_else (tree, tree, tree);
44 static void expand_virtual_init (tree, tree);
45 static tree sort_mem_initializers (tree, tree);
46 static tree initializing_context (tree);
47 static void expand_cleanup_for_base (tree, tree);
48 static tree dfs_initialize_vtbl_ptrs (tree, void *);
49 static tree build_field_list (tree, tree, int *);
50 static int diagnose_uninitialized_cst_or_ref_member_1 (tree, tree, bool, bool);
51 
52 static GTY(()) tree fn;
53 
54 /* We are about to generate some complex initialization code.
55    Conceptually, it is all a single expression.  However, we may want
56    to include conditionals, loops, and other such statement-level
57    constructs.  Therefore, we build the initialization code inside a
58    statement-expression.  This function starts such an expression.
59    STMT_EXPR_P and COMPOUND_STMT_P are filled in by this function;
60    pass them back to finish_init_stmts when the expression is
61    complete.  */
62 
63 static bool
begin_init_stmts(tree * stmt_expr_p,tree * compound_stmt_p)64 begin_init_stmts (tree *stmt_expr_p, tree *compound_stmt_p)
65 {
66   bool is_global = !building_stmt_list_p ();
67 
68   *stmt_expr_p = begin_stmt_expr ();
69   *compound_stmt_p = begin_compound_stmt (BCS_NO_SCOPE);
70 
71   return is_global;
72 }
73 
74 /* Finish out the statement-expression begun by the previous call to
75    begin_init_stmts.  Returns the statement-expression itself.  */
76 
77 static tree
finish_init_stmts(bool is_global,tree stmt_expr,tree compound_stmt)78 finish_init_stmts (bool is_global, tree stmt_expr, tree compound_stmt)
79 {
80   finish_compound_stmt (compound_stmt);
81 
82   stmt_expr = finish_stmt_expr (stmt_expr, true);
83 
84   gcc_assert (!building_stmt_list_p () == is_global);
85 
86   return stmt_expr;
87 }
88 
89 /* Constructors */
90 
91 /* Called from initialize_vtbl_ptrs via dfs_walk.  BINFO is the base
92    which we want to initialize the vtable pointer for, DATA is
93    TREE_LIST whose TREE_VALUE is the this ptr expression.  */
94 
95 static tree
dfs_initialize_vtbl_ptrs(tree binfo,void * data)96 dfs_initialize_vtbl_ptrs (tree binfo, void *data)
97 {
98   if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
99     return dfs_skip_bases;
100 
101   if (!BINFO_PRIMARY_P (binfo) || BINFO_VIRTUAL_P (binfo))
102     {
103       tree base_ptr = TREE_VALUE ((tree) data);
104 
105       base_ptr = build_base_path (PLUS_EXPR, base_ptr, binfo, /*nonnull=*/1,
106 				  tf_warning_or_error);
107 
108       expand_virtual_init (binfo, base_ptr);
109     }
110 
111   return NULL_TREE;
112 }
113 
114 /* Initialize all the vtable pointers in the object pointed to by
115    ADDR.  */
116 
117 void
initialize_vtbl_ptrs(tree addr)118 initialize_vtbl_ptrs (tree addr)
119 {
120   tree list;
121   tree type;
122 
123   type = TREE_TYPE (TREE_TYPE (addr));
124   list = build_tree_list (type, addr);
125 
126   /* Walk through the hierarchy, initializing the vptr in each base
127      class.  We do these in pre-order because we can't find the virtual
128      bases for a class until we've initialized the vtbl for that
129      class.  */
130   dfs_walk_once (TYPE_BINFO (type), dfs_initialize_vtbl_ptrs, NULL, list);
131 }
132 
133 /* Return an expression for the zero-initialization of an object with
134    type T.  This expression will either be a constant (in the case
135    that T is a scalar), or a CONSTRUCTOR (in the case that T is an
136    aggregate), or NULL (in the case that T does not require
137    initialization).  In either case, the value can be used as
138    DECL_INITIAL for a decl of the indicated TYPE; it is a valid static
139    initializer. If NELTS is non-NULL, and TYPE is an ARRAY_TYPE, NELTS
140    is the number of elements in the array.  If STATIC_STORAGE_P is
141    TRUE, initializers are only generated for entities for which
142    zero-initialization does not simply mean filling the storage with
143    zero bytes.  FIELD_SIZE, if non-NULL, is the bit size of the field,
144    subfields with bit positions at or above that bit size shouldn't
145    be added.  Note that this only works when the result is assigned
146    to a base COMPONENT_REF; if we only have a pointer to the base subobject,
147    expand_assignment will end up clearing the full size of TYPE.  */
148 
149 static tree
build_zero_init_1(tree type,tree nelts,bool static_storage_p,tree field_size)150 build_zero_init_1 (tree type, tree nelts, bool static_storage_p,
151 		   tree field_size)
152 {
153   tree init = NULL_TREE;
154 
155   /* [dcl.init]
156 
157      To zero-initialize an object of type T means:
158 
159      -- if T is a scalar type, the storage is set to the value of zero
160 	converted to T.
161 
162      -- if T is a non-union class type, the storage for each nonstatic
163 	data member and each base-class subobject is zero-initialized.
164 
165      -- if T is a union type, the storage for its first data member is
166 	zero-initialized.
167 
168      -- if T is an array type, the storage for each element is
169 	zero-initialized.
170 
171      -- if T is a reference type, no initialization is performed.  */
172 
173   gcc_assert (nelts == NULL_TREE || TREE_CODE (nelts) == INTEGER_CST);
174 
175   if (type == error_mark_node)
176     ;
177   else if (static_storage_p && zero_init_p (type))
178     /* In order to save space, we do not explicitly build initializers
179        for items that do not need them.  GCC's semantics are that
180        items with static storage duration that are not otherwise
181        initialized are initialized to zero.  */
182     ;
183   else if (TYPE_PTR_OR_PTRMEM_P (type))
184     init = fold (convert (type, nullptr_node));
185   else if (NULLPTR_TYPE_P (type))
186     init = build_int_cst (type, 0);
187   else if (SCALAR_TYPE_P (type))
188     init = fold (convert (type, integer_zero_node));
189   else if (RECORD_OR_UNION_CODE_P (TREE_CODE (type)))
190     {
191       tree field;
192       vec<constructor_elt, va_gc> *v = NULL;
193 
194       /* Iterate over the fields, building initializations.  */
195       for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
196 	{
197 	  if (TREE_CODE (field) != FIELD_DECL)
198 	    continue;
199 
200 	  if (TREE_TYPE (field) == error_mark_node)
201 	    continue;
202 
203 	  /* Don't add virtual bases for base classes if they are beyond
204 	     the size of the current field, that means it is present
205 	     somewhere else in the object.  */
206 	  if (field_size)
207 	    {
208 	      tree bitpos = bit_position (field);
209 	      if (TREE_CODE (bitpos) == INTEGER_CST
210 		  && !tree_int_cst_lt (bitpos, field_size))
211 		continue;
212 	    }
213 
214 	  /* Note that for class types there will be FIELD_DECLs
215 	     corresponding to base classes as well.  Thus, iterating
216 	     over TYPE_FIELDs will result in correct initialization of
217 	     all of the subobjects.  */
218 	  if (!static_storage_p || !zero_init_p (TREE_TYPE (field)))
219 	    {
220 	      tree new_field_size
221 		= (DECL_FIELD_IS_BASE (field)
222 		   && DECL_SIZE (field)
223 		   && TREE_CODE (DECL_SIZE (field)) == INTEGER_CST)
224 		  ? DECL_SIZE (field) : NULL_TREE;
225 	      tree value = build_zero_init_1 (TREE_TYPE (field),
226 					      /*nelts=*/NULL_TREE,
227 					      static_storage_p,
228 					      new_field_size);
229 	      if (value)
230 		CONSTRUCTOR_APPEND_ELT(v, field, value);
231 	    }
232 
233 	  /* For unions, only the first field is initialized.  */
234 	  if (TREE_CODE (type) == UNION_TYPE)
235 	    break;
236 	}
237 
238       /* Build a constructor to contain the initializations.  */
239       init = build_constructor (type, v);
240     }
241   else if (TREE_CODE (type) == ARRAY_TYPE)
242     {
243       tree max_index;
244       vec<constructor_elt, va_gc> *v = NULL;
245 
246       /* Iterate over the array elements, building initializations.  */
247       if (nelts)
248 	max_index = fold_build2_loc (input_location, MINUS_EXPR,
249 				     TREE_TYPE (nelts), nelts,
250 				     build_one_cst (TREE_TYPE (nelts)));
251       /* Treat flexible array members like [0] arrays.  */
252       else if (TYPE_DOMAIN (type) == NULL_TREE)
253 	return NULL_TREE;
254       else
255 	max_index = array_type_nelts (type);
256 
257       /* If we have an error_mark here, we should just return error mark
258 	 as we don't know the size of the array yet.  */
259       if (max_index == error_mark_node)
260 	return error_mark_node;
261       gcc_assert (TREE_CODE (max_index) == INTEGER_CST);
262 
263       /* A zero-sized array, which is accepted as an extension, will
264 	 have an upper bound of -1.  */
265       if (!integer_minus_onep (max_index))
266 	{
267 	  constructor_elt ce;
268 
269 	  /* If this is a one element array, we just use a regular init.  */
270 	  if (integer_zerop (max_index))
271 	    ce.index = size_zero_node;
272 	  else
273 	    ce.index = build2 (RANGE_EXPR, sizetype, size_zero_node,
274 			       max_index);
275 
276 	  ce.value = build_zero_init_1 (TREE_TYPE (type), /*nelts=*/NULL_TREE,
277 					static_storage_p, NULL_TREE);
278 	  if (ce.value)
279 	    {
280 	      vec_alloc (v, 1);
281 	      v->quick_push (ce);
282 	    }
283 	}
284 
285       /* Build a constructor to contain the initializations.  */
286       init = build_constructor (type, v);
287     }
288   else if (VECTOR_TYPE_P (type))
289     init = build_zero_cst (type);
290   else
291     gcc_assert (TYPE_REF_P (type));
292 
293   /* In all cases, the initializer is a constant.  */
294   if (init)
295     TREE_CONSTANT (init) = 1;
296 
297   return init;
298 }
299 
300 /* Return an expression for the zero-initialization of an object with
301    type T.  This expression will either be a constant (in the case
302    that T is a scalar), or a CONSTRUCTOR (in the case that T is an
303    aggregate), or NULL (in the case that T does not require
304    initialization).  In either case, the value can be used as
305    DECL_INITIAL for a decl of the indicated TYPE; it is a valid static
306    initializer. If NELTS is non-NULL, and TYPE is an ARRAY_TYPE, NELTS
307    is the number of elements in the array.  If STATIC_STORAGE_P is
308    TRUE, initializers are only generated for entities for which
309    zero-initialization does not simply mean filling the storage with
310    zero bytes.  */
311 
312 tree
build_zero_init(tree type,tree nelts,bool static_storage_p)313 build_zero_init (tree type, tree nelts, bool static_storage_p)
314 {
315   return build_zero_init_1 (type, nelts, static_storage_p, NULL_TREE);
316 }
317 
318 /* Return a suitable initializer for value-initializing an object of type
319    TYPE, as described in [dcl.init].  */
320 
321 tree
build_value_init(tree type,tsubst_flags_t complain)322 build_value_init (tree type, tsubst_flags_t complain)
323 {
324   /* [dcl.init]
325 
326      To value-initialize an object of type T means:
327 
328      - if T is a class type (clause 9) with either no default constructor
329        (12.1) or a default constructor that is user-provided or deleted,
330        then the object is default-initialized;
331 
332      - if T is a (possibly cv-qualified) class type without a user-provided
333        or deleted default constructor, then the object is zero-initialized
334        and the semantic constraints for default-initialization are checked,
335        and if T has a non-trivial default constructor, the object is
336        default-initialized;
337 
338      - if T is an array type, then each element is value-initialized;
339 
340      - otherwise, the object is zero-initialized.
341 
342      A program that calls for default-initialization or
343      value-initialization of an entity of reference type is ill-formed.  */
344 
345   /* The AGGR_INIT_EXPR tweaking below breaks in templates.  */
346   gcc_assert (!processing_template_decl
347 	      || (SCALAR_TYPE_P (type) || TREE_CODE (type) == ARRAY_TYPE));
348 
349   if (CLASS_TYPE_P (type)
350       && type_build_ctor_call (type))
351     {
352       tree ctor =
353 	 build_special_member_call (NULL_TREE, complete_ctor_identifier,
354 				    NULL, type, LOOKUP_NORMAL,
355 				    complain);
356       if (ctor == error_mark_node)
357 	return ctor;
358       tree fn = NULL_TREE;
359       if (TREE_CODE (ctor) == CALL_EXPR)
360 	fn = get_callee_fndecl (ctor);
361       ctor = build_aggr_init_expr (type, ctor);
362       if (fn && user_provided_p (fn))
363 	return ctor;
364       else if (TYPE_HAS_COMPLEX_DFLT (type))
365 	{
366 	  /* This is a class that needs constructing, but doesn't have
367 	     a user-provided constructor.  So we need to zero-initialize
368 	     the object and then call the implicitly defined ctor.
369 	     This will be handled in simplify_aggr_init_expr.  */
370 	  AGGR_INIT_ZERO_FIRST (ctor) = 1;
371 	  return ctor;
372 	}
373     }
374 
375   /* Discard any access checking during subobject initialization;
376      the checks are implied by the call to the ctor which we have
377      verified is OK (cpp0x/defaulted46.C).  */
378   push_deferring_access_checks (dk_deferred);
379   tree r = build_value_init_noctor (type, complain);
380   pop_deferring_access_checks ();
381   return r;
382 }
383 
384 /* Like build_value_init, but don't call the constructor for TYPE.  Used
385    for base initializers.  */
386 
387 tree
build_value_init_noctor(tree type,tsubst_flags_t complain)388 build_value_init_noctor (tree type, tsubst_flags_t complain)
389 {
390   if (!COMPLETE_TYPE_P (type))
391     {
392       if (complain & tf_error)
393 	error ("value-initialization of incomplete type %qT", type);
394       return error_mark_node;
395     }
396   /* FIXME the class and array cases should just use digest_init once it is
397      SFINAE-enabled.  */
398   if (CLASS_TYPE_P (type))
399     {
400       gcc_assert (!TYPE_HAS_COMPLEX_DFLT (type)
401 		  || errorcount != 0);
402 
403       if (TREE_CODE (type) != UNION_TYPE)
404 	{
405 	  tree field;
406 	  vec<constructor_elt, va_gc> *v = NULL;
407 
408 	  /* Iterate over the fields, building initializations.  */
409 	  for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
410 	    {
411 	      tree ftype, value;
412 
413 	      if (TREE_CODE (field) != FIELD_DECL)
414 		continue;
415 
416 	      ftype = TREE_TYPE (field);
417 
418 	      if (ftype == error_mark_node)
419 		continue;
420 
421 	      /* Ignore flexible array members for value initialization.  */
422 	      if (TREE_CODE (ftype) == ARRAY_TYPE
423 		  && !COMPLETE_TYPE_P (ftype)
424 		  && !TYPE_DOMAIN (ftype)
425 		  && COMPLETE_TYPE_P (TREE_TYPE (ftype))
426 		  && (next_initializable_field (DECL_CHAIN (field))
427 		      == NULL_TREE))
428 		continue;
429 
430 	      /* We could skip vfields and fields of types with
431 		 user-defined constructors, but I think that won't improve
432 		 performance at all; it should be simpler in general just
433 		 to zero out the entire object than try to only zero the
434 		 bits that actually need it.  */
435 
436 	      /* Note that for class types there will be FIELD_DECLs
437 		 corresponding to base classes as well.  Thus, iterating
438 		 over TYPE_FIELDs will result in correct initialization of
439 		 all of the subobjects.  */
440 	      value = build_value_init (ftype, complain);
441 	      value = maybe_constant_init (value);
442 
443 	      if (value == error_mark_node)
444 		return error_mark_node;
445 
446 	      CONSTRUCTOR_APPEND_ELT(v, field, value);
447 
448 	      /* We shouldn't have gotten here for anything that would need
449 		 non-trivial initialization, and gimplify_init_ctor_preeval
450 		 would need to be fixed to allow it.  */
451 	      gcc_assert (TREE_CODE (value) != TARGET_EXPR
452 			  && TREE_CODE (value) != AGGR_INIT_EXPR);
453 	    }
454 
455 	  /* Build a constructor to contain the zero- initializations.  */
456 	  return build_constructor (type, v);
457 	}
458     }
459   else if (TREE_CODE (type) == ARRAY_TYPE)
460     {
461       vec<constructor_elt, va_gc> *v = NULL;
462 
463       /* Iterate over the array elements, building initializations.  */
464       tree max_index = array_type_nelts (type);
465 
466       /* If we have an error_mark here, we should just return error mark
467 	 as we don't know the size of the array yet.  */
468       if (max_index == error_mark_node)
469 	{
470 	  if (complain & tf_error)
471 	    error ("cannot value-initialize array of unknown bound %qT",
472 		   type);
473 	  return error_mark_node;
474 	}
475       gcc_assert (TREE_CODE (max_index) == INTEGER_CST);
476 
477       /* A zero-sized array, which is accepted as an extension, will
478 	 have an upper bound of -1.  */
479       if (!tree_int_cst_equal (max_index, integer_minus_one_node))
480 	{
481 	  constructor_elt ce;
482 
483 	  /* If this is a one element array, we just use a regular init.  */
484 	  if (tree_int_cst_equal (size_zero_node, max_index))
485 	    ce.index = size_zero_node;
486 	  else
487 	    ce.index = build2 (RANGE_EXPR, sizetype, size_zero_node, max_index);
488 
489 	  ce.value = build_value_init (TREE_TYPE (type), complain);
490 	  ce.value = maybe_constant_init (ce.value);
491 	  if (ce.value == error_mark_node)
492 	    return error_mark_node;
493 
494 	  vec_alloc (v, 1);
495 	  v->quick_push (ce);
496 
497 	  /* We shouldn't have gotten here for anything that would need
498 	     non-trivial initialization, and gimplify_init_ctor_preeval
499 	     would need to be fixed to allow it.  */
500 	  gcc_assert (TREE_CODE (ce.value) != TARGET_EXPR
501 		      && TREE_CODE (ce.value) != AGGR_INIT_EXPR);
502 	}
503 
504       /* Build a constructor to contain the initializations.  */
505       return build_constructor (type, v);
506     }
507   else if (TREE_CODE (type) == FUNCTION_TYPE)
508     {
509       if (complain & tf_error)
510 	error ("value-initialization of function type %qT", type);
511       return error_mark_node;
512     }
513   else if (TYPE_REF_P (type))
514     {
515       if (complain & tf_error)
516 	error ("value-initialization of reference type %qT", type);
517       return error_mark_node;
518     }
519 
520   return build_zero_init (type, NULL_TREE, /*static_storage_p=*/false);
521 }
522 
523 /* Initialize current class with INIT, a TREE_LIST of
524    arguments for a target constructor. If TREE_LIST is void_type_node,
525    an empty initializer list was given.  */
526 
527 static void
perform_target_ctor(tree init)528 perform_target_ctor (tree init)
529 {
530   tree decl = current_class_ref;
531   tree type = current_class_type;
532 
533   finish_expr_stmt (build_aggr_init (decl, init,
534 				     LOOKUP_NORMAL|LOOKUP_DELEGATING_CONS,
535 				     tf_warning_or_error));
536   if (type_build_dtor_call (type))
537     {
538       tree expr = build_delete (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)) 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       tree *slot;
566       if (TREE_CODE (init) == DEFAULT_ARG)
567 	/* Unparsed.  */;
568       else if (nsdmi_inst && (slot = nsdmi_inst->get (member)))
569 	init = *slot;
570       /* Check recursive instantiation.  */
571       else if (DECL_INSTANTIATING_NSDMI_P (member))
572 	{
573 	  if (complain & tf_error)
574 	    error_at (expr_loc, "recursive instantiation of default member "
575 		      "initializer for %qD", member);
576 	  init = error_mark_node;
577 	}
578       else
579 	{
580 	  cp_evaluated ev;
581 
582 	  location_t sloc = input_location;
583 	  input_location = expr_loc;
584 
585 	  DECL_INSTANTIATING_NSDMI_P (member) = 1;
586 
587 	  bool pushed = false;
588 	  tree ctx = DECL_CONTEXT (member);
589 	  if (!currently_open_class (ctx)
590 	      && !LOCAL_CLASS_P (ctx))
591 	    {
592 	      push_to_top_level ();
593 	      push_nested_class (ctx);
594 	      pushed = true;
595 	    }
596 
597 	  gcc_checking_assert (!processing_template_decl);
598 
599 	  inject_this_parameter (ctx, TYPE_UNQUALIFIED);
600 
601 	  start_lambda_scope (member);
602 
603 	  /* Do deferred instantiation of the NSDMI.  */
604 	  init = (tsubst_copy_and_build
605 		  (init, DECL_TI_ARGS (member),
606 		   complain, member, /*function_p=*/false,
607 		   /*integral_constant_expression_p=*/false));
608 	  init = digest_nsdmi_init (member, init, complain);
609 
610 	  finish_lambda_scope ();
611 
612 	  DECL_INSTANTIATING_NSDMI_P (member) = 0;
613 
614 	  if (init != error_mark_node)
615 	    {
616 	      if (!nsdmi_inst)
617 		nsdmi_inst = tree_cache_map::create_ggc (37);
618 	      nsdmi_inst->put (member, init);
619 	    }
620 
621 	  if (pushed)
622 	    {
623 	      pop_nested_class ();
624 	      pop_from_top_level ();
625 	    }
626 
627 	  input_location = sloc;
628 	}
629     }
630   else
631     init = DECL_INITIAL (member);
632 
633   if (init && TREE_CODE (init) == DEFAULT_ARG)
634     {
635       if (complain & tf_error)
636 	{
637 	  error ("default member initializer for %qD required before the end "
638 		 "of its enclosing class", member);
639 	  inform (location_of (init), "defined here");
640 	  DECL_INITIAL (member) = error_mark_node;
641 	}
642       init = error_mark_node;
643     }
644 
645   if (in_ctor)
646     {
647       current_class_ptr = save_ccp;
648       current_class_ref = save_ccr;
649     }
650   else
651     {
652       /* Use a PLACEHOLDER_EXPR when we don't have a 'this' parameter to
653 	 refer to; constexpr evaluation knows what to do with it.  */
654       current_class_ref = build0 (PLACEHOLDER_EXPR, DECL_CONTEXT (member));
655       current_class_ptr = build_address (current_class_ref);
656     }
657 
658   /* Strip redundant TARGET_EXPR so we don't need to remap it, and
659      so the aggregate init code below will see a CONSTRUCTOR.  */
660   bool simple_target = (init && SIMPLE_TARGET_EXPR_P (init));
661   if (simple_target)
662     init = TARGET_EXPR_INITIAL (init);
663   init = break_out_target_exprs (init, /*loc*/true);
664   if (simple_target && TREE_CODE (init) != CONSTRUCTOR)
665     /* Now put it back so C++17 copy elision works.  */
666     init = get_target_expr (init);
667 
668   current_class_ptr = save_ccp;
669   current_class_ref = save_ccr;
670   return init;
671 }
672 
673 /* Diagnose the flexible array MEMBER if its INITializer is non-null
674    and return true if so.  Otherwise return false.  */
675 
676 bool
maybe_reject_flexarray_init(tree member,tree init)677 maybe_reject_flexarray_init (tree member, tree init)
678 {
679   tree type = TREE_TYPE (member);
680 
681   if (!init
682       || TREE_CODE (type) != ARRAY_TYPE
683       || TYPE_DOMAIN (type))
684     return false;
685 
686   /* Point at the flexible array member declaration if it's initialized
687      in-class, and at the ctor if it's initialized in a ctor member
688      initializer list.  */
689   location_t loc;
690   if (DECL_INITIAL (member) == init
691       || !current_function_decl
692       || DECL_DEFAULTED_FN (current_function_decl))
693     loc = DECL_SOURCE_LOCATION (member);
694   else
695     loc = DECL_SOURCE_LOCATION (current_function_decl);
696 
697   error_at (loc, "initializer for flexible array member %q#D", member);
698   return true;
699 }
700 
701 /* If INIT's value can come from a call to std::initializer_list<T>::begin,
702    return that function.  Otherwise, NULL_TREE.  */
703 
704 static tree
find_list_begin(tree init)705 find_list_begin (tree init)
706 {
707   STRIP_NOPS (init);
708   while (TREE_CODE (init) == COMPOUND_EXPR)
709     init = TREE_OPERAND (init, 1);
710   STRIP_NOPS (init);
711   if (TREE_CODE (init) == COND_EXPR)
712     {
713       tree left = TREE_OPERAND (init, 1);
714       if (!left)
715 	left = TREE_OPERAND (init, 0);
716       left = find_list_begin (left);
717       if (left)
718 	return left;
719       return find_list_begin (TREE_OPERAND (init, 2));
720     }
721   if (TREE_CODE (init) == CALL_EXPR)
722     if (tree fn = get_callee_fndecl (init))
723       if (id_equal (DECL_NAME (fn), "begin")
724 	  && is_std_init_list (DECL_CONTEXT (fn)))
725 	return fn;
726   return NULL_TREE;
727 }
728 
729 /* If INIT initializing MEMBER is copying the address of the underlying array
730    of an initializer_list, warn.  */
731 
732 static void
maybe_warn_list_ctor(tree member,tree init)733 maybe_warn_list_ctor (tree member, tree init)
734 {
735   tree memtype = TREE_TYPE (member);
736   if (!init || !TYPE_PTR_P (memtype)
737       || !is_list_ctor (current_function_decl))
738     return;
739 
740   tree parms = FUNCTION_FIRST_USER_PARMTYPE (current_function_decl);
741   tree initlist = non_reference (TREE_VALUE (parms));
742   tree targs = CLASSTYPE_TI_ARGS (initlist);
743   tree elttype = TREE_VEC_ELT (targs, 0);
744 
745   if (!same_type_ignoring_top_level_qualifiers_p
746       (TREE_TYPE (memtype), elttype))
747     return;
748 
749   tree begin = find_list_begin (init);
750   if (!begin)
751     return;
752 
753   location_t loc = cp_expr_loc_or_loc (init, input_location);
754   warning_at (loc, OPT_Winit_list_lifetime,
755 	     "initializing %qD from %qE does not extend the lifetime "
756 	     "of the underlying array", member, begin);
757 }
758 
759 /* Initialize MEMBER, a FIELD_DECL, with INIT, a TREE_LIST of
760    arguments.  If TREE_LIST is void_type_node, an empty initializer
761    list was given; if NULL_TREE no initializer was given.  */
762 
763 static void
perform_member_init(tree member,tree init)764 perform_member_init (tree member, tree init)
765 {
766   tree decl;
767   tree type = TREE_TYPE (member);
768 
769   /* Use the non-static data member initializer if there was no
770      mem-initializer for this field.  */
771   if (init == NULL_TREE)
772     init = get_nsdmi (member, /*ctor*/true, tf_warning_or_error);
773 
774   if (init == error_mark_node)
775     return;
776 
777   /* Effective C++ rule 12 requires that all data members be
778      initialized.  */
779   if (warn_ecpp && init == NULL_TREE && TREE_CODE (type) != ARRAY_TYPE)
780     warning_at (DECL_SOURCE_LOCATION (current_function_decl), OPT_Weffc__,
781 		"%qD should be initialized in the member initialization list",
782 		member);
783 
784   /* Get an lvalue for the data member.  */
785   decl = build_class_member_access_expr (current_class_ref, member,
786 					 /*access_path=*/NULL_TREE,
787 					 /*preserve_reference=*/true,
788 					 tf_warning_or_error);
789   if (decl == error_mark_node)
790     return;
791 
792   if (warn_init_self && init && TREE_CODE (init) == TREE_LIST
793       && TREE_CHAIN (init) == NULL_TREE)
794     {
795       tree val = TREE_VALUE (init);
796       /* Handle references.  */
797       if (REFERENCE_REF_P (val))
798 	val = TREE_OPERAND (val, 0);
799       if (TREE_CODE (val) == COMPONENT_REF && TREE_OPERAND (val, 1) == member
800 	  && TREE_OPERAND (val, 0) == current_class_ref)
801 	warning_at (DECL_SOURCE_LOCATION (current_function_decl),
802 		    OPT_Winit_self, "%qD is initialized with itself",
803 		    member);
804     }
805 
806   if (init == void_type_node)
807     {
808       /* mem() means value-initialization.  */
809       if (TREE_CODE (type) == ARRAY_TYPE)
810 	{
811 	  init = build_vec_init_expr (type, init, tf_warning_or_error);
812 	  init = build2 (INIT_EXPR, type, decl, init);
813 	  finish_expr_stmt (init);
814 	}
815       else
816 	{
817 	  tree value = build_value_init (type, tf_warning_or_error);
818 	  if (value == error_mark_node)
819 	    return;
820 	  init = build2 (INIT_EXPR, type, decl, value);
821 	  finish_expr_stmt (init);
822 	}
823     }
824   /* Deal with this here, as we will get confused if we try to call the
825      assignment op for an anonymous union.  This can happen in a
826      synthesized copy constructor.  */
827   else if (ANON_AGGR_TYPE_P (type))
828     {
829       if (init)
830 	{
831 	  init = build2 (INIT_EXPR, type, decl, TREE_VALUE (init));
832 	  finish_expr_stmt (init);
833 	}
834     }
835   else if (init
836 	   && (TYPE_REF_P (type)
837 	       /* Pre-digested NSDMI.  */
838 	       || (((TREE_CODE (init) == CONSTRUCTOR
839 		     && TREE_TYPE (init) == type)
840 		    /* { } mem-initializer.  */
841 		    || (TREE_CODE (init) == TREE_LIST
842 			&& DIRECT_LIST_INIT_P (TREE_VALUE (init))))
843 		   && (CP_AGGREGATE_TYPE_P (type)
844 		       || is_std_init_list (type)))))
845     {
846       /* With references and list-initialization, we need to deal with
847 	 extending temporary lifetimes.  12.2p5: "A temporary bound to a
848 	 reference member in a constructor’s ctor-initializer (12.6.2)
849 	 persists until the constructor exits."  */
850       unsigned i; tree t;
851       vec<tree, va_gc> *cleanups = make_tree_vector ();
852       if (TREE_CODE (init) == TREE_LIST)
853 	init = build_x_compound_expr_from_list (init, ELK_MEM_INIT,
854 						tf_warning_or_error);
855       if (TREE_TYPE (init) != type)
856 	{
857 	  if (BRACE_ENCLOSED_INITIALIZER_P (init)
858 	      && CP_AGGREGATE_TYPE_P (type))
859 	    init = reshape_init (type, init, tf_warning_or_error);
860 	  init = digest_init (type, init, tf_warning_or_error);
861 	}
862       if (init == error_mark_node)
863 	return;
864       if (DECL_SIZE (member) && integer_zerop (DECL_SIZE (member))
865 	  && !TREE_SIDE_EFFECTS (init))
866 	/* Don't add trivial initialization of an empty base/field, as they
867 	   might not be ordered the way the back-end expects.  */
868 	return;
869       /* A FIELD_DECL doesn't really have a suitable lifetime, but
870 	 make_temporary_var_for_ref_to_temp will treat it as automatic and
871 	 set_up_extended_ref_temp wants to use the decl in a warning.  */
872       init = extend_ref_init_temps (member, init, &cleanups);
873       if (TREE_CODE (type) == ARRAY_TYPE
874 	  && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (type)))
875 	init = build_vec_init_expr (type, init, tf_warning_or_error);
876       init = build2 (INIT_EXPR, type, decl, init);
877       finish_expr_stmt (init);
878       FOR_EACH_VEC_ELT (*cleanups, i, t)
879 	push_cleanup (decl, t, false);
880       release_tree_vector (cleanups);
881     }
882   else if (type_build_ctor_call (type)
883 	   || (init && CLASS_TYPE_P (strip_array_types (type))))
884     {
885       if (TREE_CODE (type) == ARRAY_TYPE)
886 	{
887 	  if (init)
888 	    {
889 	      /* Check to make sure the member initializer is valid and
890 		 something like a CONSTRUCTOR in: T a[] = { 1, 2 } and
891 		 if it isn't, return early to avoid triggering another
892 		 error below.  */
893 	      if (maybe_reject_flexarray_init (member, init))
894 		return;
895 
896 	      if (TREE_CODE (init) != TREE_LIST || TREE_CHAIN (init))
897 		init = error_mark_node;
898 	      else
899 		init = TREE_VALUE (init);
900 
901 	      if (BRACE_ENCLOSED_INITIALIZER_P (init))
902 		init = digest_init (type, init, tf_warning_or_error);
903 	    }
904 	  if (init == NULL_TREE
905 	      || same_type_ignoring_top_level_qualifiers_p (type,
906 							    TREE_TYPE (init)))
907 	    {
908 	      if (TYPE_DOMAIN (type) && TYPE_MAX_VALUE (TYPE_DOMAIN (type)))
909 		{
910 		  /* Initialize the array only if it's not a flexible
911 		     array member (i.e., if it has an upper bound).  */
912 		  init = build_vec_init_expr (type, init, tf_warning_or_error);
913 		  init = build2 (INIT_EXPR, type, decl, init);
914 		  finish_expr_stmt (init);
915 		}
916 	    }
917 	  else
918 	    error ("invalid initializer for array member %q#D", member);
919 	}
920       else
921 	{
922 	  int flags = LOOKUP_NORMAL;
923 	  if (DECL_DEFAULTED_FN (current_function_decl))
924 	    flags |= LOOKUP_DEFAULTED;
925 	  if (CP_TYPE_CONST_P (type)
926 	      && init == NULL_TREE
927 	      && default_init_uninitialized_part (type))
928 	    {
929 	      /* TYPE_NEEDS_CONSTRUCTING can be set just because we have a
930 		 vtable; still give this diagnostic.  */
931 	      auto_diagnostic_group d;
932 	      if (permerror (DECL_SOURCE_LOCATION (current_function_decl),
933 			     "uninitialized const member in %q#T", type))
934 		inform (DECL_SOURCE_LOCATION (member),
935 			"%q#D should be initialized", member );
936 	    }
937 	  finish_expr_stmt (build_aggr_init (decl, init, flags,
938 					     tf_warning_or_error));
939 	}
940     }
941   else
942     {
943       if (init == NULL_TREE)
944 	{
945 	  tree core_type;
946 	  /* member traversal: note it leaves init NULL */
947 	  if (TYPE_REF_P (type))
948 	    {
949 	      auto_diagnostic_group d;
950 	      if (permerror (DECL_SOURCE_LOCATION (current_function_decl),
951 			     "uninitialized reference member in %q#T", type))
952 		inform (DECL_SOURCE_LOCATION (member),
953 			"%q#D should be initialized", member);
954 	    }
955 	  else if (CP_TYPE_CONST_P (type))
956 	    {
957 	      auto_diagnostic_group d;
958 	      if (permerror (DECL_SOURCE_LOCATION (current_function_decl),
959 			     "uninitialized const member in %q#T", type))
960 		  inform (DECL_SOURCE_LOCATION (member),
961 			  "%q#D should be initialized", member );
962 	    }
963 
964 	  core_type = strip_array_types (type);
965 
966 	  if (CLASS_TYPE_P (core_type)
967 	      && (CLASSTYPE_READONLY_FIELDS_NEED_INIT (core_type)
968 		  || CLASSTYPE_REF_FIELDS_NEED_INIT (core_type)))
969 	    diagnose_uninitialized_cst_or_ref_member (core_type,
970 						      /*using_new=*/false,
971 						      /*complain=*/true);
972 	}
973       else if (TREE_CODE (init) == TREE_LIST)
974 	/* There was an explicit member initialization.  Do some work
975 	   in that case.  */
976 	init = build_x_compound_expr_from_list (init, ELK_MEM_INIT,
977 						tf_warning_or_error);
978 
979       maybe_warn_list_ctor (member, init);
980 
981       /* Reject a member initializer for a flexible array member.  */
982       if (init && !maybe_reject_flexarray_init (member, init))
983 	finish_expr_stmt (cp_build_modify_expr (input_location, decl,
984 						INIT_EXPR, init,
985 						tf_warning_or_error));
986     }
987 
988   if (type_build_dtor_call (type))
989     {
990       tree expr;
991 
992       expr = build_class_member_access_expr (current_class_ref, member,
993 					     /*access_path=*/NULL_TREE,
994 					     /*preserve_reference=*/false,
995 					     tf_warning_or_error);
996       expr = build_delete (type, expr, sfk_complete_destructor,
997 			   LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR, 0,
998 			   tf_warning_or_error);
999 
1000       if (expr != error_mark_node
1001 	  && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
1002 	finish_eh_cleanup (expr);
1003     }
1004 }
1005 
1006 /* Returns a TREE_LIST containing (as the TREE_PURPOSE of each node) all
1007    the FIELD_DECLs on the TYPE_FIELDS list for T, in reverse order.  */
1008 
1009 static tree
build_field_list(tree t,tree list,int * uses_unions_or_anon_p)1010 build_field_list (tree t, tree list, int *uses_unions_or_anon_p)
1011 {
1012   tree fields;
1013 
1014   /* Note whether or not T is a union.  */
1015   if (TREE_CODE (t) == UNION_TYPE)
1016     *uses_unions_or_anon_p = 1;
1017 
1018   for (fields = TYPE_FIELDS (t); fields; fields = DECL_CHAIN (fields))
1019     {
1020       tree fieldtype;
1021 
1022       /* Skip CONST_DECLs for enumeration constants and so forth.  */
1023       if (TREE_CODE (fields) != FIELD_DECL || DECL_ARTIFICIAL (fields))
1024 	continue;
1025 
1026       fieldtype = TREE_TYPE (fields);
1027 
1028       /* For an anonymous struct or union, we must recursively
1029 	 consider the fields of the anonymous type.  They can be
1030 	 directly initialized from the constructor.  */
1031       if (ANON_AGGR_TYPE_P (fieldtype))
1032 	{
1033 	  /* Add this field itself.  Synthesized copy constructors
1034 	     initialize the entire aggregate.  */
1035 	  list = tree_cons (fields, NULL_TREE, list);
1036 	  /* And now add the fields in the anonymous aggregate.  */
1037 	  list = build_field_list (fieldtype, list, uses_unions_or_anon_p);
1038 	  *uses_unions_or_anon_p = 1;
1039 	}
1040       /* Add this field.  */
1041       else if (DECL_NAME (fields))
1042 	list = tree_cons (fields, NULL_TREE, list);
1043     }
1044 
1045   return list;
1046 }
1047 
1048 /* Return the innermost aggregate scope for FIELD, whether that is
1049    the enclosing class or an anonymous aggregate within it.  */
1050 
1051 static tree
innermost_aggr_scope(tree field)1052 innermost_aggr_scope (tree field)
1053 {
1054   if (ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1055     return TREE_TYPE (field);
1056   else
1057     return DECL_CONTEXT (field);
1058 }
1059 
1060 /* The MEM_INITS are a TREE_LIST.  The TREE_PURPOSE of each list gives
1061    a FIELD_DECL or BINFO in T that needs initialization.  The
1062    TREE_VALUE gives the initializer, or list of initializer arguments.
1063 
1064    Return a TREE_LIST containing all of the initializations required
1065    for T, in the order in which they should be performed.  The output
1066    list has the same format as the input.  */
1067 
1068 static tree
sort_mem_initializers(tree t,tree mem_inits)1069 sort_mem_initializers (tree t, tree mem_inits)
1070 {
1071   tree init;
1072   tree base, binfo, base_binfo;
1073   tree sorted_inits;
1074   tree next_subobject;
1075   vec<tree, va_gc> *vbases;
1076   int i;
1077   int uses_unions_or_anon_p = 0;
1078 
1079   /* Build up a list of initializations.  The TREE_PURPOSE of entry
1080      will be the subobject (a FIELD_DECL or BINFO) to initialize.  The
1081      TREE_VALUE will be the constructor arguments, or NULL if no
1082      explicit initialization was provided.  */
1083   sorted_inits = NULL_TREE;
1084 
1085   /* Process the virtual bases.  */
1086   for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
1087        vec_safe_iterate (vbases, i, &base); i++)
1088     sorted_inits = tree_cons (base, NULL_TREE, sorted_inits);
1089 
1090   /* Process the direct bases.  */
1091   for (binfo = TYPE_BINFO (t), i = 0;
1092        BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
1093     if (!BINFO_VIRTUAL_P (base_binfo))
1094       sorted_inits = tree_cons (base_binfo, NULL_TREE, sorted_inits);
1095 
1096   /* Process the non-static data members.  */
1097   sorted_inits = build_field_list (t, sorted_inits, &uses_unions_or_anon_p);
1098   /* Reverse the entire list of initializations, so that they are in
1099      the order that they will actually be performed.  */
1100   sorted_inits = nreverse (sorted_inits);
1101 
1102   /* If the user presented the initializers in an order different from
1103      that in which they will actually occur, we issue a warning.  Keep
1104      track of the next subobject which can be explicitly initialized
1105      without issuing a warning.  */
1106   next_subobject = sorted_inits;
1107 
1108   /* Go through the explicit initializers, filling in TREE_PURPOSE in
1109      the SORTED_INITS.  */
1110   for (init = mem_inits; init; init = TREE_CHAIN (init))
1111     {
1112       tree subobject;
1113       tree subobject_init;
1114 
1115       subobject = TREE_PURPOSE (init);
1116 
1117       /* If the explicit initializers are in sorted order, then
1118 	 SUBOBJECT will be NEXT_SUBOBJECT, or something following
1119 	 it.  */
1120       for (subobject_init = next_subobject;
1121 	   subobject_init;
1122 	   subobject_init = TREE_CHAIN (subobject_init))
1123 	if (TREE_PURPOSE (subobject_init) == subobject)
1124 	  break;
1125 
1126       /* Issue a warning if the explicit initializer order does not
1127 	 match that which will actually occur.
1128 	 ??? Are all these on the correct lines?  */
1129       if (warn_reorder && !subobject_init)
1130 	{
1131 	  if (TREE_CODE (TREE_PURPOSE (next_subobject)) == FIELD_DECL)
1132 	    warning_at (DECL_SOURCE_LOCATION (TREE_PURPOSE (next_subobject)),
1133 			OPT_Wreorder, "%qD will be initialized after",
1134 			TREE_PURPOSE (next_subobject));
1135 	  else
1136 	    warning (OPT_Wreorder, "base %qT will be initialized after",
1137 		     TREE_PURPOSE (next_subobject));
1138 	  if (TREE_CODE (subobject) == FIELD_DECL)
1139 	    warning_at (DECL_SOURCE_LOCATION (subobject),
1140 			OPT_Wreorder, "  %q#D", subobject);
1141 	  else
1142 	    warning (OPT_Wreorder, "  base %qT", subobject);
1143 	  warning_at (DECL_SOURCE_LOCATION (current_function_decl),
1144 		      OPT_Wreorder, "  when initialized here");
1145 	}
1146 
1147       /* Look again, from the beginning of the list.  */
1148       if (!subobject_init)
1149 	{
1150 	  subobject_init = sorted_inits;
1151 	  while (TREE_PURPOSE (subobject_init) != subobject)
1152 	    subobject_init = TREE_CHAIN (subobject_init);
1153 	}
1154 
1155       /* It is invalid to initialize the same subobject more than
1156 	 once.  */
1157       if (TREE_VALUE (subobject_init))
1158 	{
1159 	  if (TREE_CODE (subobject) == FIELD_DECL)
1160 	    error_at (DECL_SOURCE_LOCATION (current_function_decl),
1161 		      "multiple initializations given for %qD",
1162 		      subobject);
1163 	  else
1164 	    error_at (DECL_SOURCE_LOCATION (current_function_decl),
1165 		      "multiple initializations given for base %qT",
1166 		      subobject);
1167 	}
1168 
1169       /* Record the initialization.  */
1170       TREE_VALUE (subobject_init) = TREE_VALUE (init);
1171       next_subobject = subobject_init;
1172     }
1173 
1174   /* [class.base.init]
1175 
1176      If a ctor-initializer specifies more than one mem-initializer for
1177      multiple members of the same union (including members of
1178      anonymous unions), the ctor-initializer is ill-formed.
1179 
1180      Here we also splice out uninitialized union members.  */
1181   if (uses_unions_or_anon_p)
1182     {
1183       tree *last_p = NULL;
1184       tree *p;
1185       for (p = &sorted_inits; *p; )
1186 	{
1187 	  tree field;
1188 	  tree ctx;
1189 
1190 	  init = *p;
1191 
1192 	  field = TREE_PURPOSE (init);
1193 
1194 	  /* Skip base classes.  */
1195 	  if (TREE_CODE (field) != FIELD_DECL)
1196 	    goto next;
1197 
1198 	  /* If this is an anonymous aggregate with no explicit initializer,
1199 	     splice it out.  */
1200 	  if (!TREE_VALUE (init) && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1201 	    goto splice;
1202 
1203 	  /* See if this field is a member of a union, or a member of a
1204 	     structure contained in a union, etc.  */
1205 	  ctx = innermost_aggr_scope (field);
1206 
1207 	  /* If this field is not a member of a union, skip it.  */
1208 	  if (TREE_CODE (ctx) != UNION_TYPE
1209 	      && !ANON_AGGR_TYPE_P (ctx))
1210 	    goto next;
1211 
1212 	  /* If this union member has no explicit initializer and no NSDMI,
1213 	     splice it out.  */
1214 	  if (TREE_VALUE (init) || DECL_INITIAL (field))
1215 	    /* OK.  */;
1216 	  else
1217 	    goto splice;
1218 
1219 	  /* It's only an error if we have two initializers for the same
1220 	     union type.  */
1221 	  if (!last_p)
1222 	    {
1223 	      last_p = p;
1224 	      goto next;
1225 	    }
1226 
1227 	  /* See if LAST_FIELD and the field initialized by INIT are
1228 	     members of the same union (or the union itself). If so, there's
1229 	     a problem, unless they're actually members of the same structure
1230 	     which is itself a member of a union.  For example, given:
1231 
1232 	       union { struct { int i; int j; }; };
1233 
1234 	     initializing both `i' and `j' makes sense.  */
1235 	  ctx = common_enclosing_class
1236 	    (innermost_aggr_scope (field),
1237 	     innermost_aggr_scope (TREE_PURPOSE (*last_p)));
1238 
1239 	  if (ctx && (TREE_CODE (ctx) == UNION_TYPE
1240 		      || ctx == TREE_TYPE (TREE_PURPOSE (*last_p))))
1241 	    {
1242 	      /* A mem-initializer hides an NSDMI.  */
1243 	      if (TREE_VALUE (init) && !TREE_VALUE (*last_p))
1244 		*last_p = TREE_CHAIN (*last_p);
1245 	      else if (TREE_VALUE (*last_p) && !TREE_VALUE (init))
1246 		goto splice;
1247 	      else
1248 		{
1249 		  error_at (DECL_SOURCE_LOCATION (current_function_decl),
1250 			    "initializations for multiple members of %qT",
1251 			    ctx);
1252 		  goto splice;
1253 		}
1254 	    }
1255 
1256 	  last_p = p;
1257 
1258 	next:
1259 	  p = &TREE_CHAIN (*p);
1260 	  continue;
1261 	splice:
1262 	  *p = TREE_CHAIN (*p);
1263 	  continue;
1264 	}
1265     }
1266 
1267   return sorted_inits;
1268 }
1269 
1270 /* Callback for cp_walk_tree to mark all PARM_DECLs in a tree as read.  */
1271 
1272 static tree
mark_exp_read_r(tree * tp,int *,void *)1273 mark_exp_read_r (tree *tp, int *, void *)
1274 {
1275   tree t = *tp;
1276   if (TREE_CODE (t) == PARM_DECL)
1277     mark_exp_read (t);
1278   return NULL_TREE;
1279 }
1280 
1281 /* Initialize all bases and members of CURRENT_CLASS_TYPE.  MEM_INITS
1282    is a TREE_LIST giving the explicit mem-initializer-list for the
1283    constructor.  The TREE_PURPOSE of each entry is a subobject (a
1284    FIELD_DECL or a BINFO) of the CURRENT_CLASS_TYPE.  The TREE_VALUE
1285    is a TREE_LIST giving the arguments to the constructor or
1286    void_type_node for an empty list of arguments.  */
1287 
1288 void
emit_mem_initializers(tree mem_inits)1289 emit_mem_initializers (tree mem_inits)
1290 {
1291   int flags = LOOKUP_NORMAL;
1292 
1293   /* We will already have issued an error message about the fact that
1294      the type is incomplete.  */
1295   if (!COMPLETE_TYPE_P (current_class_type))
1296     return;
1297 
1298   if (mem_inits
1299       && TYPE_P (TREE_PURPOSE (mem_inits))
1300       && same_type_p (TREE_PURPOSE (mem_inits), current_class_type))
1301     {
1302       /* Delegating constructor. */
1303       gcc_assert (TREE_CHAIN (mem_inits) == NULL_TREE);
1304       perform_target_ctor (TREE_VALUE (mem_inits));
1305       return;
1306     }
1307 
1308   if (DECL_DEFAULTED_FN (current_function_decl)
1309       && ! DECL_INHERITED_CTOR (current_function_decl))
1310     flags |= LOOKUP_DEFAULTED;
1311 
1312   /* Sort the mem-initializers into the order in which the
1313      initializations should be performed.  */
1314   mem_inits = sort_mem_initializers (current_class_type, mem_inits);
1315 
1316   in_base_initializer = 1;
1317 
1318   /* Initialize base classes.  */
1319   for (; (mem_inits
1320 	  && TREE_CODE (TREE_PURPOSE (mem_inits)) != FIELD_DECL);
1321        mem_inits = TREE_CHAIN (mem_inits))
1322     {
1323       tree subobject = TREE_PURPOSE (mem_inits);
1324       tree arguments = TREE_VALUE (mem_inits);
1325 
1326       /* We already have issued an error message.  */
1327       if (arguments == error_mark_node)
1328 	continue;
1329 
1330       /* Suppress access control when calling the inherited ctor.  */
1331       bool inherited_base = (DECL_INHERITED_CTOR (current_function_decl)
1332 			     && flag_new_inheriting_ctors
1333 			     && arguments);
1334       if (inherited_base)
1335 	push_deferring_access_checks (dk_deferred);
1336 
1337       if (arguments == NULL_TREE)
1338 	{
1339 	  /* If these initializations are taking place in a copy constructor,
1340 	     the base class should probably be explicitly initialized if there
1341 	     is a user-defined constructor in the base class (other than the
1342 	     default constructor, which will be called anyway).  */
1343 	  if (extra_warnings
1344 	      && DECL_COPY_CONSTRUCTOR_P (current_function_decl)
1345 	      && type_has_user_nondefault_constructor (BINFO_TYPE (subobject)))
1346 	    warning_at (DECL_SOURCE_LOCATION (current_function_decl),
1347 			OPT_Wextra, "base class %q#T should be explicitly "
1348 			"initialized in the copy constructor",
1349 			BINFO_TYPE (subobject));
1350 	}
1351 
1352       /* Initialize the base.  */
1353       if (!BINFO_VIRTUAL_P (subobject))
1354 	{
1355 	  tree base_addr;
1356 
1357 	  base_addr = build_base_path (PLUS_EXPR, current_class_ptr,
1358 				       subobject, 1, tf_warning_or_error);
1359 	  expand_aggr_init_1 (subobject, NULL_TREE,
1360 			      cp_build_fold_indirect_ref (base_addr),
1361 			      arguments,
1362 			      flags,
1363                               tf_warning_or_error);
1364 	  expand_cleanup_for_base (subobject, NULL_TREE);
1365 	}
1366       else if (!ABSTRACT_CLASS_TYPE_P (current_class_type))
1367 	/* C++14 DR1658 Means we do not have to construct vbases of
1368 	   abstract classes.  */
1369 	construct_virtual_base (subobject, arguments);
1370       else
1371 	/* When not constructing vbases of abstract classes, at least mark
1372 	   the arguments expressions as read to avoid
1373 	   -Wunused-but-set-parameter false positives.  */
1374 	cp_walk_tree (&arguments, mark_exp_read_r, NULL, NULL);
1375 
1376       if (inherited_base)
1377 	pop_deferring_access_checks ();
1378     }
1379   in_base_initializer = 0;
1380 
1381   /* Initialize the vptrs.  */
1382   initialize_vtbl_ptrs (current_class_ptr);
1383 
1384   /* Initialize the data members.  */
1385   while (mem_inits)
1386     {
1387       perform_member_init (TREE_PURPOSE (mem_inits),
1388 			   TREE_VALUE (mem_inits));
1389       mem_inits = TREE_CHAIN (mem_inits);
1390     }
1391 }
1392 
1393 /* Returns the address of the vtable (i.e., the value that should be
1394    assigned to the vptr) for BINFO.  */
1395 
1396 tree
build_vtbl_address(tree binfo)1397 build_vtbl_address (tree binfo)
1398 {
1399   tree binfo_for = binfo;
1400   tree vtbl;
1401 
1402   if (BINFO_VPTR_INDEX (binfo) && BINFO_VIRTUAL_P (binfo))
1403     /* If this is a virtual primary base, then the vtable we want to store
1404        is that for the base this is being used as the primary base of.  We
1405        can't simply skip the initialization, because we may be expanding the
1406        inits of a subobject constructor where the virtual base layout
1407        can be different.  */
1408     while (BINFO_PRIMARY_P (binfo_for))
1409       binfo_for = BINFO_INHERITANCE_CHAIN (binfo_for);
1410 
1411   /* Figure out what vtable BINFO's vtable is based on, and mark it as
1412      used.  */
1413   vtbl = get_vtbl_decl_for_binfo (binfo_for);
1414   TREE_USED (vtbl) = true;
1415 
1416   /* Now compute the address to use when initializing the vptr.  */
1417   vtbl = unshare_expr (BINFO_VTABLE (binfo_for));
1418   if (VAR_P (vtbl))
1419     vtbl = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (vtbl)), vtbl);
1420 
1421   return vtbl;
1422 }
1423 
1424 /* This code sets up the virtual function tables appropriate for
1425    the pointer DECL.  It is a one-ply initialization.
1426 
1427    BINFO is the exact type that DECL is supposed to be.  In
1428    multiple inheritance, this might mean "C's A" if C : A, B.  */
1429 
1430 static void
expand_virtual_init(tree binfo,tree decl)1431 expand_virtual_init (tree binfo, tree decl)
1432 {
1433   tree vtbl, vtbl_ptr;
1434   tree vtt_index;
1435 
1436   /* Compute the initializer for vptr.  */
1437   vtbl = build_vtbl_address (binfo);
1438 
1439   /* We may get this vptr from a VTT, if this is a subobject
1440      constructor or subobject destructor.  */
1441   vtt_index = BINFO_VPTR_INDEX (binfo);
1442   if (vtt_index)
1443     {
1444       tree vtbl2;
1445       tree vtt_parm;
1446 
1447       /* Compute the value to use, when there's a VTT.  */
1448       vtt_parm = current_vtt_parm;
1449       vtbl2 = fold_build_pointer_plus (vtt_parm, vtt_index);
1450       vtbl2 = cp_build_fold_indirect_ref (vtbl2);
1451       vtbl2 = convert (TREE_TYPE (vtbl), vtbl2);
1452 
1453       /* The actual initializer is the VTT value only in the subobject
1454 	 constructor.  In maybe_clone_body we'll substitute NULL for
1455 	 the vtt_parm in the case of the non-subobject constructor.  */
1456       vtbl = build_if_in_charge (vtbl, vtbl2);
1457     }
1458 
1459   /* Compute the location of the vtpr.  */
1460   vtbl_ptr = build_vfield_ref (cp_build_fold_indirect_ref (decl),
1461 			       TREE_TYPE (binfo));
1462   gcc_assert (vtbl_ptr != error_mark_node);
1463 
1464   /* Assign the vtable to the vptr.  */
1465   vtbl = convert_force (TREE_TYPE (vtbl_ptr), vtbl, 0, tf_warning_or_error);
1466   finish_expr_stmt (cp_build_modify_expr (input_location, vtbl_ptr, NOP_EXPR,
1467 					  vtbl, tf_warning_or_error));
1468 }
1469 
1470 /* If an exception is thrown in a constructor, those base classes already
1471    constructed must be destroyed.  This function creates the cleanup
1472    for BINFO, which has just been constructed.  If FLAG is non-NULL,
1473    it is a DECL which is nonzero when this base needs to be
1474    destroyed.  */
1475 
1476 static void
expand_cleanup_for_base(tree binfo,tree flag)1477 expand_cleanup_for_base (tree binfo, tree flag)
1478 {
1479   tree expr;
1480 
1481   if (!type_build_dtor_call (BINFO_TYPE (binfo)))
1482     return;
1483 
1484   /* Call the destructor.  */
1485   expr = build_special_member_call (current_class_ref,
1486 				    base_dtor_identifier,
1487 				    NULL,
1488 				    binfo,
1489 				    LOOKUP_NORMAL | LOOKUP_NONVIRTUAL,
1490                                     tf_warning_or_error);
1491 
1492   if (TYPE_HAS_TRIVIAL_DESTRUCTOR (BINFO_TYPE (binfo)))
1493     return;
1494 
1495   if (flag)
1496     expr = fold_build3_loc (input_location,
1497 			COND_EXPR, void_type_node,
1498 			c_common_truthvalue_conversion (input_location, flag),
1499 			expr, integer_zero_node);
1500 
1501   finish_eh_cleanup (expr);
1502 }
1503 
1504 /* Construct the virtual base-class VBASE passing the ARGUMENTS to its
1505    constructor.  */
1506 
1507 static void
construct_virtual_base(tree vbase,tree arguments)1508 construct_virtual_base (tree vbase, tree arguments)
1509 {
1510   tree inner_if_stmt;
1511   tree exp;
1512   tree flag;
1513 
1514   /* If there are virtual base classes with destructors, we need to
1515      emit cleanups to destroy them if an exception is thrown during
1516      the construction process.  These exception regions (i.e., the
1517      period during which the cleanups must occur) begin from the time
1518      the construction is complete to the end of the function.  If we
1519      create a conditional block in which to initialize the
1520      base-classes, then the cleanup region for the virtual base begins
1521      inside a block, and ends outside of that block.  This situation
1522      confuses the sjlj exception-handling code.  Therefore, we do not
1523      create a single conditional block, but one for each
1524      initialization.  (That way the cleanup regions always begin
1525      in the outer block.)  We trust the back end to figure out
1526      that the FLAG will not change across initializations, and
1527      avoid doing multiple tests.  */
1528   flag = DECL_CHAIN (DECL_ARGUMENTS (current_function_decl));
1529   inner_if_stmt = begin_if_stmt ();
1530   finish_if_stmt_cond (flag, inner_if_stmt);
1531 
1532   /* Compute the location of the virtual base.  If we're
1533      constructing virtual bases, then we must be the most derived
1534      class.  Therefore, we don't have to look up the virtual base;
1535      we already know where it is.  */
1536   exp = convert_to_base_statically (current_class_ref, vbase);
1537 
1538   expand_aggr_init_1 (vbase, current_class_ref, exp, arguments,
1539 		      0, tf_warning_or_error);
1540   finish_then_clause (inner_if_stmt);
1541   finish_if_stmt (inner_if_stmt);
1542 
1543   expand_cleanup_for_base (vbase, flag);
1544 }
1545 
1546 /* Find the context in which this FIELD can be initialized.  */
1547 
1548 static tree
initializing_context(tree field)1549 initializing_context (tree field)
1550 {
1551   tree t = DECL_CONTEXT (field);
1552 
1553   /* Anonymous union members can be initialized in the first enclosing
1554      non-anonymous union context.  */
1555   while (t && ANON_AGGR_TYPE_P (t))
1556     t = TYPE_CONTEXT (t);
1557   return t;
1558 }
1559 
1560 /* Function to give error message if member initialization specification
1561    is erroneous.  FIELD is the member we decided to initialize.
1562    TYPE is the type for which the initialization is being performed.
1563    FIELD must be a member of TYPE.
1564 
1565    MEMBER_NAME is the name of the member.  */
1566 
1567 static int
member_init_ok_or_else(tree field,tree type,tree member_name)1568 member_init_ok_or_else (tree field, tree type, tree member_name)
1569 {
1570   if (field == error_mark_node)
1571     return 0;
1572   if (!field)
1573     {
1574       error ("class %qT does not have any field named %qD", type,
1575 	     member_name);
1576       return 0;
1577     }
1578   if (VAR_P (field))
1579     {
1580       error ("%q#D is a static data member; it can only be "
1581 	     "initialized at its definition",
1582 	     field);
1583       return 0;
1584     }
1585   if (TREE_CODE (field) != FIELD_DECL)
1586     {
1587       error ("%q#D is not a non-static data member of %qT",
1588 	     field, type);
1589       return 0;
1590     }
1591   if (initializing_context (field) != type)
1592     {
1593       error ("class %qT does not have any field named %qD", type,
1594 		member_name);
1595       return 0;
1596     }
1597 
1598   return 1;
1599 }
1600 
1601 /* NAME is a FIELD_DECL, an IDENTIFIER_NODE which names a field, or it
1602    is a _TYPE node or TYPE_DECL which names a base for that type.
1603    Check the validity of NAME, and return either the base _TYPE, base
1604    binfo, or the FIELD_DECL of the member.  If NAME is invalid, return
1605    NULL_TREE and issue a diagnostic.
1606 
1607    An old style unnamed direct single base construction is permitted,
1608    where NAME is NULL.  */
1609 
1610 tree
expand_member_init(tree name)1611 expand_member_init (tree name)
1612 {
1613   tree basetype;
1614   tree field;
1615 
1616   if (!current_class_ref)
1617     return NULL_TREE;
1618 
1619   if (!name)
1620     {
1621       /* This is an obsolete unnamed base class initializer.  The
1622 	 parser will already have warned about its use.  */
1623       switch (BINFO_N_BASE_BINFOS (TYPE_BINFO (current_class_type)))
1624 	{
1625 	case 0:
1626 	  error ("unnamed initializer for %qT, which has no base classes",
1627 		 current_class_type);
1628 	  return NULL_TREE;
1629 	case 1:
1630 	  basetype = BINFO_TYPE
1631 	    (BINFO_BASE_BINFO (TYPE_BINFO (current_class_type), 0));
1632 	  break;
1633 	default:
1634 	  error ("unnamed initializer for %qT, which uses multiple inheritance",
1635 		 current_class_type);
1636 	  return NULL_TREE;
1637       }
1638     }
1639   else if (TYPE_P (name))
1640     {
1641       basetype = TYPE_MAIN_VARIANT (name);
1642       name = TYPE_NAME (name);
1643     }
1644   else if (TREE_CODE (name) == TYPE_DECL)
1645     basetype = TYPE_MAIN_VARIANT (TREE_TYPE (name));
1646   else
1647     basetype = NULL_TREE;
1648 
1649   if (basetype)
1650     {
1651       tree class_binfo;
1652       tree direct_binfo;
1653       tree virtual_binfo;
1654       int i;
1655 
1656       if (current_template_parms
1657 	  || same_type_p (basetype, current_class_type))
1658 	  return basetype;
1659 
1660       class_binfo = TYPE_BINFO (current_class_type);
1661       direct_binfo = NULL_TREE;
1662       virtual_binfo = NULL_TREE;
1663 
1664       /* Look for a direct base.  */
1665       for (i = 0; BINFO_BASE_ITERATE (class_binfo, i, direct_binfo); ++i)
1666 	if (SAME_BINFO_TYPE_P (BINFO_TYPE (direct_binfo), basetype))
1667 	  break;
1668 
1669       /* Look for a virtual base -- unless the direct base is itself
1670 	 virtual.  */
1671       if (!direct_binfo || !BINFO_VIRTUAL_P (direct_binfo))
1672 	virtual_binfo = binfo_for_vbase (basetype, current_class_type);
1673 
1674       /* [class.base.init]
1675 
1676 	 If a mem-initializer-id is ambiguous because it designates
1677 	 both a direct non-virtual base class and an inherited virtual
1678 	 base class, the mem-initializer is ill-formed.  */
1679       if (direct_binfo && virtual_binfo)
1680 	{
1681 	  error ("%qD is both a direct base and an indirect virtual base",
1682 		 basetype);
1683 	  return NULL_TREE;
1684 	}
1685 
1686       if (!direct_binfo && !virtual_binfo)
1687 	{
1688 	  if (CLASSTYPE_VBASECLASSES (current_class_type))
1689 	    error ("type %qT is not a direct or virtual base of %qT",
1690 		   basetype, current_class_type);
1691 	  else
1692 	    error ("type %qT is not a direct base of %qT",
1693 		   basetype, current_class_type);
1694 	  return NULL_TREE;
1695 	}
1696 
1697       return direct_binfo ? direct_binfo : virtual_binfo;
1698     }
1699   else
1700     {
1701       if (identifier_p (name))
1702 	field = lookup_field (current_class_type, name, 1, false);
1703       else
1704 	field = name;
1705 
1706       if (member_init_ok_or_else (field, current_class_type, name))
1707 	return field;
1708     }
1709 
1710   return NULL_TREE;
1711 }
1712 
1713 /* This is like `expand_member_init', only it stores one aggregate
1714    value into another.
1715 
1716    INIT comes in two flavors: it is either a value which
1717    is to be stored in EXP, or it is a parameter list
1718    to go to a constructor, which will operate on EXP.
1719    If INIT is not a parameter list for a constructor, then set
1720    LOOKUP_ONLYCONVERTING.
1721    If FLAGS is LOOKUP_ONLYCONVERTING then it is the = init form of
1722    the initializer, if FLAGS is 0, then it is the (init) form.
1723    If `init' is a CONSTRUCTOR, then we emit a warning message,
1724    explaining that such initializations are invalid.
1725 
1726    If INIT resolves to a CALL_EXPR which happens to return
1727    something of the type we are looking for, then we know
1728    that we can safely use that call to perform the
1729    initialization.
1730 
1731    The virtual function table pointer cannot be set up here, because
1732    we do not really know its type.
1733 
1734    This never calls operator=().
1735 
1736    When initializing, nothing is CONST.
1737 
1738    A default copy constructor may have to be used to perform the
1739    initialization.
1740 
1741    A constructor or a conversion operator may have to be used to
1742    perform the initialization, but not both, as it would be ambiguous.  */
1743 
1744 tree
build_aggr_init(tree exp,tree init,int flags,tsubst_flags_t complain)1745 build_aggr_init (tree exp, tree init, int flags, tsubst_flags_t complain)
1746 {
1747   tree stmt_expr;
1748   tree compound_stmt;
1749   int destroy_temps;
1750   tree type = TREE_TYPE (exp);
1751   int was_const = TREE_READONLY (exp);
1752   int was_volatile = TREE_THIS_VOLATILE (exp);
1753   int is_global;
1754 
1755   if (init == error_mark_node)
1756     return error_mark_node;
1757 
1758   location_t init_loc = (init
1759 			 ? cp_expr_loc_or_loc (init, input_location)
1760 			 : location_of (exp));
1761 
1762   TREE_READONLY (exp) = 0;
1763   TREE_THIS_VOLATILE (exp) = 0;
1764 
1765   if (TREE_CODE (type) == ARRAY_TYPE)
1766     {
1767       tree itype = init ? TREE_TYPE (init) : NULL_TREE;
1768       int from_array = 0;
1769 
1770       if (VAR_P (exp) && DECL_DECOMPOSITION_P (exp))
1771 	{
1772 	  from_array = 1;
1773 	  init = mark_rvalue_use (init);
1774 	  if (init
1775 	      && DECL_P (tree_strip_any_location_wrapper (init))
1776 	      && !(flags & LOOKUP_ONLYCONVERTING))
1777 	    {
1778 	      /* Wrap the initializer in a CONSTRUCTOR so that build_vec_init
1779 		 recognizes it as direct-initialization.  */
1780 	      init = build_constructor_single (init_list_type_node,
1781 					       NULL_TREE, init);
1782 	      CONSTRUCTOR_IS_DIRECT_INIT (init) = true;
1783 	    }
1784 	}
1785       else
1786 	{
1787 	  /* Must arrange to initialize each element of EXP
1788 	     from elements of INIT.  */
1789 	  if (cv_qualified_p (type))
1790 	    TREE_TYPE (exp) = cv_unqualified (type);
1791 	  if (itype && cv_qualified_p (itype))
1792 	    TREE_TYPE (init) = cv_unqualified (itype);
1793 	  from_array = (itype && same_type_p (TREE_TYPE (init),
1794 					      TREE_TYPE (exp)));
1795 
1796 	  if (init && !BRACE_ENCLOSED_INITIALIZER_P (init)
1797 	      && (!from_array
1798 		  || (TREE_CODE (init) != CONSTRUCTOR
1799 		      /* Can happen, eg, handling the compound-literals
1800 			 extension (ext/complit12.C).  */
1801 		      && TREE_CODE (init) != TARGET_EXPR)))
1802 	    {
1803 	      if (complain & tf_error)
1804 		error_at (init_loc, "array must be initialized "
1805 			  "with a brace-enclosed initializer");
1806 	      return error_mark_node;
1807 	    }
1808 	}
1809 
1810       stmt_expr = build_vec_init (exp, NULL_TREE, init,
1811 				  /*explicit_value_init_p=*/false,
1812 				  from_array,
1813                                   complain);
1814       TREE_READONLY (exp) = was_const;
1815       TREE_THIS_VOLATILE (exp) = was_volatile;
1816       TREE_TYPE (exp) = type;
1817       /* Restore the type of init unless it was used directly.  */
1818       if (init && TREE_CODE (stmt_expr) != INIT_EXPR)
1819 	TREE_TYPE (init) = itype;
1820       return stmt_expr;
1821     }
1822 
1823   if (init && init != void_type_node
1824       && TREE_CODE (init) != TREE_LIST
1825       && !(TREE_CODE (init) == TARGET_EXPR
1826 	   && TARGET_EXPR_DIRECT_INIT_P (init))
1827       && !DIRECT_LIST_INIT_P (init))
1828     flags |= LOOKUP_ONLYCONVERTING;
1829 
1830   is_global = begin_init_stmts (&stmt_expr, &compound_stmt);
1831   destroy_temps = stmts_are_full_exprs_p ();
1832   current_stmt_tree ()->stmts_are_full_exprs_p = 0;
1833   expand_aggr_init_1 (TYPE_BINFO (type), exp, exp,
1834 		      init, LOOKUP_NORMAL|flags, complain);
1835   stmt_expr = finish_init_stmts (is_global, stmt_expr, compound_stmt);
1836   current_stmt_tree ()->stmts_are_full_exprs_p = destroy_temps;
1837   TREE_READONLY (exp) = was_const;
1838   TREE_THIS_VOLATILE (exp) = was_volatile;
1839 
1840   if ((VAR_P (exp) || TREE_CODE (exp) == PARM_DECL)
1841       && TREE_SIDE_EFFECTS (stmt_expr)
1842       && !lookup_attribute ("warn_unused", TYPE_ATTRIBUTES (type)))
1843     /* Just know that we've seen something for this node.  */
1844     TREE_USED (exp) = 1;
1845 
1846   return stmt_expr;
1847 }
1848 
1849 static void
expand_default_init(tree binfo,tree true_exp,tree exp,tree init,int flags,tsubst_flags_t complain)1850 expand_default_init (tree binfo, tree true_exp, tree exp, tree init, int flags,
1851                      tsubst_flags_t complain)
1852 {
1853   tree type = TREE_TYPE (exp);
1854 
1855   /* It fails because there may not be a constructor which takes
1856      its own type as the first (or only parameter), but which does
1857      take other types via a conversion.  So, if the thing initializing
1858      the expression is a unit element of type X, first try X(X&),
1859      followed by initialization by X.  If neither of these work
1860      out, then look hard.  */
1861   tree rval;
1862   vec<tree, va_gc> *parms;
1863 
1864   /* If we have direct-initialization from an initializer list, pull
1865      it out of the TREE_LIST so the code below can see it.  */
1866   if (init && TREE_CODE (init) == TREE_LIST
1867       && DIRECT_LIST_INIT_P (TREE_VALUE (init)))
1868     {
1869       gcc_checking_assert ((flags & LOOKUP_ONLYCONVERTING) == 0
1870 			   && TREE_CHAIN (init) == NULL_TREE);
1871       init = TREE_VALUE (init);
1872       /* Only call reshape_init if it has not been called earlier
1873 	 by the callers.  */
1874       if (BRACE_ENCLOSED_INITIALIZER_P (init) && CP_AGGREGATE_TYPE_P (type))
1875 	init = reshape_init (type, init, complain);
1876     }
1877 
1878   if (init && BRACE_ENCLOSED_INITIALIZER_P (init)
1879       && CP_AGGREGATE_TYPE_P (type))
1880     /* A brace-enclosed initializer for an aggregate.  In C++0x this can
1881        happen for direct-initialization, too.  */
1882     init = digest_init (type, init, complain);
1883 
1884   /* A CONSTRUCTOR of the target's type is a previously digested
1885      initializer, whether that happened just above or in
1886      cp_parser_late_parsing_nsdmi.
1887 
1888      A TARGET_EXPR with TARGET_EXPR_DIRECT_INIT_P or TARGET_EXPR_LIST_INIT_P
1889      set represents the whole initialization, so we shouldn't build up
1890      another ctor call.  */
1891   if (init
1892       && (TREE_CODE (init) == CONSTRUCTOR
1893 	  || (TREE_CODE (init) == TARGET_EXPR
1894 	      && (TARGET_EXPR_DIRECT_INIT_P (init)
1895 		  || TARGET_EXPR_LIST_INIT_P (init))))
1896       && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (init), type))
1897     {
1898       /* Early initialization via a TARGET_EXPR only works for
1899 	 complete objects.  */
1900       gcc_assert (TREE_CODE (init) == CONSTRUCTOR || true_exp == exp);
1901 
1902       init = build2 (INIT_EXPR, TREE_TYPE (exp), exp, init);
1903       TREE_SIDE_EFFECTS (init) = 1;
1904       finish_expr_stmt (init);
1905       return;
1906     }
1907 
1908   if (init && TREE_CODE (init) != TREE_LIST
1909       && (flags & LOOKUP_ONLYCONVERTING))
1910     {
1911       /* Base subobjects should only get direct-initialization.  */
1912       gcc_assert (true_exp == exp);
1913 
1914       if (flags & DIRECT_BIND)
1915 	/* Do nothing.  We hit this in two cases:  Reference initialization,
1916 	   where we aren't initializing a real variable, so we don't want
1917 	   to run a new constructor; and catching an exception, where we
1918 	   have already built up the constructor call so we could wrap it
1919 	   in an exception region.  */;
1920       else
1921 	init = ocp_convert (type, init, CONV_IMPLICIT|CONV_FORCE_TEMP,
1922 			    flags, complain);
1923 
1924       if (TREE_CODE (init) == MUST_NOT_THROW_EXPR)
1925 	/* We need to protect the initialization of a catch parm with a
1926 	   call to terminate(), which shows up as a MUST_NOT_THROW_EXPR
1927 	   around the TARGET_EXPR for the copy constructor.  See
1928 	   initialize_handler_parm.  */
1929 	{
1930 	  TREE_OPERAND (init, 0) = build2 (INIT_EXPR, TREE_TYPE (exp), exp,
1931 					   TREE_OPERAND (init, 0));
1932 	  TREE_TYPE (init) = void_type_node;
1933 	}
1934       else
1935 	init = build2 (INIT_EXPR, TREE_TYPE (exp), exp, init);
1936       TREE_SIDE_EFFECTS (init) = 1;
1937       finish_expr_stmt (init);
1938       return;
1939     }
1940 
1941   if (init == NULL_TREE)
1942     parms = NULL;
1943   else if (TREE_CODE (init) == TREE_LIST && !TREE_TYPE (init))
1944     {
1945       parms = make_tree_vector ();
1946       for (; init != NULL_TREE; init = TREE_CHAIN (init))
1947 	vec_safe_push (parms, TREE_VALUE (init));
1948     }
1949   else
1950     parms = make_tree_vector_single (init);
1951 
1952   if (exp == current_class_ref && current_function_decl
1953       && DECL_HAS_IN_CHARGE_PARM_P (current_function_decl))
1954     {
1955       /* Delegating constructor. */
1956       tree complete;
1957       tree base;
1958       tree elt; unsigned i;
1959 
1960       /* Unshare the arguments for the second call.  */
1961       vec<tree, va_gc> *parms2 = make_tree_vector ();
1962       FOR_EACH_VEC_SAFE_ELT (parms, i, elt)
1963 	{
1964 	  elt = break_out_target_exprs (elt);
1965 	  vec_safe_push (parms2, elt);
1966 	}
1967       complete = build_special_member_call (exp, complete_ctor_identifier,
1968 					    &parms2, binfo, flags,
1969 					    complain);
1970       complete = fold_build_cleanup_point_expr (void_type_node, complete);
1971       release_tree_vector (parms2);
1972 
1973       base = build_special_member_call (exp, base_ctor_identifier,
1974 					&parms, binfo, flags,
1975 					complain);
1976       base = fold_build_cleanup_point_expr (void_type_node, base);
1977       rval = build_if_in_charge (complete, base);
1978     }
1979    else
1980     {
1981       tree ctor_name = (true_exp == exp
1982 			? complete_ctor_identifier : base_ctor_identifier);
1983 
1984       rval = build_special_member_call (exp, ctor_name, &parms, binfo, flags,
1985 					complain);
1986     }
1987 
1988   if (parms != NULL)
1989     release_tree_vector (parms);
1990 
1991   if (exp == true_exp && TREE_CODE (rval) == CALL_EXPR)
1992     {
1993       tree fn = get_callee_fndecl (rval);
1994       if (fn && DECL_DECLARED_CONSTEXPR_P (fn))
1995 	{
1996 	  tree e = maybe_constant_init (rval, exp);
1997 	  if (TREE_CONSTANT (e))
1998 	    rval = build2 (INIT_EXPR, type, exp, e);
1999 	}
2000     }
2001 
2002   /* FIXME put back convert_to_void?  */
2003   if (TREE_SIDE_EFFECTS (rval))
2004     finish_expr_stmt (rval);
2005 }
2006 
2007 /* This function is responsible for initializing EXP with INIT
2008    (if any).
2009 
2010    BINFO is the binfo of the type for who we are performing the
2011    initialization.  For example, if W is a virtual base class of A and B,
2012    and C : A, B.
2013    If we are initializing B, then W must contain B's W vtable, whereas
2014    were we initializing C, W must contain C's W vtable.
2015 
2016    TRUE_EXP is nonzero if it is the true expression being initialized.
2017    In this case, it may be EXP, or may just contain EXP.  The reason we
2018    need this is because if EXP is a base element of TRUE_EXP, we
2019    don't necessarily know by looking at EXP where its virtual
2020    baseclass fields should really be pointing.  But we do know
2021    from TRUE_EXP.  In constructors, we don't know anything about
2022    the value being initialized.
2023 
2024    FLAGS is just passed to `build_new_method_call'.  See that function
2025    for its description.  */
2026 
2027 static void
expand_aggr_init_1(tree binfo,tree true_exp,tree exp,tree init,int flags,tsubst_flags_t complain)2028 expand_aggr_init_1 (tree binfo, tree true_exp, tree exp, tree init, int flags,
2029                     tsubst_flags_t complain)
2030 {
2031   tree type = TREE_TYPE (exp);
2032 
2033   gcc_assert (init != error_mark_node && type != error_mark_node);
2034   gcc_assert (building_stmt_list_p ());
2035 
2036   /* Use a function returning the desired type to initialize EXP for us.
2037      If the function is a constructor, and its first argument is
2038      NULL_TREE, know that it was meant for us--just slide exp on
2039      in and expand the constructor.  Constructors now come
2040      as TARGET_EXPRs.  */
2041 
2042   if (init && VAR_P (exp)
2043       && COMPOUND_LITERAL_P (init))
2044     {
2045       vec<tree, va_gc> *cleanups = NULL;
2046       /* If store_init_value returns NULL_TREE, the INIT has been
2047 	 recorded as the DECL_INITIAL for EXP.  That means there's
2048 	 nothing more we have to do.  */
2049       init = store_init_value (exp, init, &cleanups, flags);
2050       if (init)
2051 	finish_expr_stmt (init);
2052       gcc_assert (!cleanups);
2053       return;
2054     }
2055 
2056   /* List-initialization from {} becomes value-initialization for non-aggregate
2057      classes with default constructors.  Handle this here when we're
2058      initializing a base, so protected access works.  */
2059   if (exp != true_exp && init && TREE_CODE (init) == TREE_LIST)
2060     {
2061       tree elt = TREE_VALUE (init);
2062       if (DIRECT_LIST_INIT_P (elt)
2063 	  && CONSTRUCTOR_ELTS (elt) == 0
2064 	  && CLASSTYPE_NON_AGGREGATE (type)
2065 	  && TYPE_HAS_DEFAULT_CONSTRUCTOR (type))
2066 	init = void_type_node;
2067     }
2068 
2069   /* If an explicit -- but empty -- initializer list was present,
2070      that's value-initialization.  */
2071   if (init == void_type_node)
2072     {
2073       /* If the type has data but no user-provided ctor, we need to zero
2074 	 out the object.  */
2075       if (!type_has_user_provided_constructor (type)
2076 	  && !is_really_empty_class (type, /*ignore_vptr*/true))
2077 	{
2078 	  tree field_size = NULL_TREE;
2079 	  if (exp != true_exp && CLASSTYPE_AS_BASE (type) != type)
2080 	    /* Don't clobber already initialized virtual bases.  */
2081 	    field_size = TYPE_SIZE (CLASSTYPE_AS_BASE (type));
2082 	  init = build_zero_init_1 (type, NULL_TREE, /*static_storage_p=*/false,
2083 				    field_size);
2084 	  init = build2 (INIT_EXPR, type, exp, init);
2085 	  finish_expr_stmt (init);
2086 	}
2087 
2088       /* If we don't need to mess with the constructor at all,
2089 	 then we're done.  */
2090       if (! type_build_ctor_call (type))
2091 	return;
2092 
2093       /* Otherwise fall through and call the constructor.  */
2094       init = NULL_TREE;
2095     }
2096 
2097   /* We know that expand_default_init can handle everything we want
2098      at this point.  */
2099   expand_default_init (binfo, true_exp, exp, init, flags, complain);
2100 }
2101 
2102 /* Report an error if TYPE is not a user-defined, class type.  If
2103    OR_ELSE is nonzero, give an error message.  */
2104 
2105 int
is_class_type(tree type,int or_else)2106 is_class_type (tree type, int or_else)
2107 {
2108   if (type == error_mark_node)
2109     return 0;
2110 
2111   if (! CLASS_TYPE_P (type))
2112     {
2113       if (or_else)
2114 	error ("%qT is not a class type", type);
2115       return 0;
2116     }
2117   return 1;
2118 }
2119 
2120 tree
get_type_value(tree name)2121 get_type_value (tree name)
2122 {
2123   if (name == error_mark_node)
2124     return NULL_TREE;
2125 
2126   if (IDENTIFIER_HAS_TYPE_VALUE (name))
2127     return IDENTIFIER_TYPE_VALUE (name);
2128   else
2129     return NULL_TREE;
2130 }
2131 
2132 /* Build a reference to a member of an aggregate.  This is not a C++
2133    `&', but really something which can have its address taken, and
2134    then act as a pointer to member, for example TYPE :: FIELD can have
2135    its address taken by saying & TYPE :: FIELD.  ADDRESS_P is true if
2136    this expression is the operand of "&".
2137 
2138    @@ Prints out lousy diagnostics for operator <typename>
2139    @@ fields.
2140 
2141    @@ This function should be rewritten and placed in search.c.  */
2142 
2143 tree
build_offset_ref(tree type,tree member,bool address_p,tsubst_flags_t complain)2144 build_offset_ref (tree type, tree member, bool address_p,
2145 		  tsubst_flags_t complain)
2146 {
2147   tree decl;
2148   tree basebinfo = NULL_TREE;
2149 
2150   /* class templates can come in as TEMPLATE_DECLs here.  */
2151   if (TREE_CODE (member) == TEMPLATE_DECL)
2152     return member;
2153 
2154   if (dependent_scope_p (type) || type_dependent_expression_p (member))
2155     return build_qualified_name (NULL_TREE, type, member,
2156 				  /*template_p=*/false);
2157 
2158   gcc_assert (TYPE_P (type));
2159   if (! is_class_type (type, 1))
2160     return error_mark_node;
2161 
2162   gcc_assert (DECL_P (member) || BASELINK_P (member));
2163   /* Callers should call mark_used before this point.  */
2164   gcc_assert (!DECL_P (member) || TREE_USED (member));
2165 
2166   type = TYPE_MAIN_VARIANT (type);
2167   if (!COMPLETE_OR_OPEN_TYPE_P (complete_type (type)))
2168     {
2169       if (complain & tf_error)
2170 	error ("incomplete type %qT does not have member %qD", type, member);
2171       return error_mark_node;
2172     }
2173 
2174   /* Entities other than non-static members need no further
2175      processing.  */
2176   if (TREE_CODE (member) == TYPE_DECL)
2177     return member;
2178   if (VAR_P (member) || TREE_CODE (member) == CONST_DECL)
2179     return convert_from_reference (member);
2180 
2181   if (TREE_CODE (member) == FIELD_DECL && DECL_C_BIT_FIELD (member))
2182     {
2183       if (complain & tf_error)
2184 	error ("invalid pointer to bit-field %qD", member);
2185       return error_mark_node;
2186     }
2187 
2188   /* Set up BASEBINFO for member lookup.  */
2189   decl = maybe_dummy_object (type, &basebinfo);
2190 
2191   /* A lot of this logic is now handled in lookup_member.  */
2192   if (BASELINK_P (member))
2193     {
2194       /* Go from the TREE_BASELINK to the member function info.  */
2195       tree t = BASELINK_FUNCTIONS (member);
2196 
2197       if (TREE_CODE (t) != TEMPLATE_ID_EXPR && !really_overloaded_fn (t))
2198 	{
2199 	  /* Get rid of a potential OVERLOAD around it.  */
2200 	  t = OVL_FIRST (t);
2201 
2202 	  /* Unique functions are handled easily.  */
2203 
2204 	  /* For non-static member of base class, we need a special rule
2205 	     for access checking [class.protected]:
2206 
2207 	       If the access is to form a pointer to member, the
2208 	       nested-name-specifier shall name the derived class
2209 	       (or any class derived from that class).  */
2210 	  bool ok;
2211 	  if (address_p && DECL_P (t)
2212 	      && DECL_NONSTATIC_MEMBER_P (t))
2213 	    ok = perform_or_defer_access_check (TYPE_BINFO (type), t, t,
2214 						complain);
2215 	  else
2216 	    ok = perform_or_defer_access_check (basebinfo, t, t,
2217 						complain);
2218 	  if (!ok)
2219 	    return error_mark_node;
2220 	  if (DECL_STATIC_FUNCTION_P (t))
2221 	    return t;
2222 	  member = t;
2223 	}
2224       else
2225 	TREE_TYPE (member) = unknown_type_node;
2226     }
2227   else if (address_p && TREE_CODE (member) == FIELD_DECL)
2228     {
2229       /* We need additional test besides the one in
2230 	 check_accessibility_of_qualified_id in case it is
2231 	 a pointer to non-static member.  */
2232       if (!perform_or_defer_access_check (TYPE_BINFO (type), member, member,
2233 					  complain))
2234 	return error_mark_node;
2235     }
2236 
2237   if (!address_p)
2238     {
2239       /* If MEMBER is non-static, then the program has fallen afoul of
2240 	 [expr.prim]:
2241 
2242 	   An id-expression that denotes a nonstatic data member or
2243 	   nonstatic member function of a class can only be used:
2244 
2245 	   -- as part of a class member access (_expr.ref_) in which the
2246 	   object-expression refers to the member's class or a class
2247 	   derived from that class, or
2248 
2249 	   -- to form a pointer to member (_expr.unary.op_), or
2250 
2251 	   -- in the body of a nonstatic member function of that class or
2252 	   of a class derived from that class (_class.mfct.nonstatic_), or
2253 
2254 	   -- in a mem-initializer for a constructor for that class or for
2255 	   a class derived from that class (_class.base.init_).  */
2256       if (DECL_NONSTATIC_MEMBER_FUNCTION_P (member))
2257 	{
2258 	  /* Build a representation of the qualified name suitable
2259 	     for use as the operand to "&" -- even though the "&" is
2260 	     not actually present.  */
2261 	  member = build2 (OFFSET_REF, TREE_TYPE (member), decl, member);
2262 	  /* In Microsoft mode, treat a non-static member function as if
2263 	     it were a pointer-to-member.  */
2264 	  if (flag_ms_extensions)
2265 	    {
2266 	      PTRMEM_OK_P (member) = 1;
2267 	      return cp_build_addr_expr (member, complain);
2268 	    }
2269 	  if (complain & tf_error)
2270 	    error ("invalid use of non-static member function %qD",
2271 		   TREE_OPERAND (member, 1));
2272 	  return error_mark_node;
2273 	}
2274       else if (TREE_CODE (member) == FIELD_DECL)
2275 	{
2276 	  if (complain & tf_error)
2277 	    error ("invalid use of non-static data member %qD", member);
2278 	  return error_mark_node;
2279 	}
2280       return member;
2281     }
2282 
2283   member = build2 (OFFSET_REF, TREE_TYPE (member), decl, member);
2284   PTRMEM_OK_P (member) = 1;
2285   return member;
2286 }
2287 
2288 /* If DECL is a scalar enumeration constant or variable with a
2289    constant initializer, return the initializer (or, its initializers,
2290    recursively); otherwise, return DECL.  If STRICT_P, the
2291    initializer is only returned if DECL is a
2292    constant-expression.  If RETURN_AGGREGATE_CST_OK_P, it is ok to
2293    return an aggregate constant.  */
2294 
2295 static tree
constant_value_1(tree decl,bool strict_p,bool return_aggregate_cst_ok_p)2296 constant_value_1 (tree decl, bool strict_p, bool return_aggregate_cst_ok_p)
2297 {
2298   while (TREE_CODE (decl) == CONST_DECL
2299 	 || decl_constant_var_p (decl)
2300 	 || (!strict_p && VAR_P (decl)
2301 	     && CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (decl))))
2302     {
2303       tree init;
2304       /* If DECL is a static data member in a template
2305 	 specialization, we must instantiate it here.  The
2306 	 initializer for the static data member is not processed
2307 	 until needed; we need it now.  */
2308       mark_used (decl, tf_none);
2309       init = DECL_INITIAL (decl);
2310       if (init == error_mark_node)
2311 	{
2312 	  if (TREE_CODE (decl) == CONST_DECL
2313 	      || DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
2314 	    /* Treat the error as a constant to avoid cascading errors on
2315 	       excessively recursive template instantiation (c++/9335).  */
2316 	    return init;
2317 	  else
2318 	    return decl;
2319 	}
2320       /* Initializers in templates are generally expanded during
2321 	 instantiation, so before that for const int i(2)
2322 	 INIT is a TREE_LIST with the actual initializer as
2323 	 TREE_VALUE.  */
2324       if (processing_template_decl
2325 	  && init
2326 	  && TREE_CODE (init) == TREE_LIST
2327 	  && TREE_CHAIN (init) == NULL_TREE)
2328 	init = TREE_VALUE (init);
2329       /* Instantiate a non-dependent initializer for user variables.  We
2330 	 mustn't do this for the temporary for an array compound literal;
2331 	 trying to instatiate the initializer will keep creating new
2332 	 temporaries until we crash.  Probably it's not useful to do it for
2333 	 other artificial variables, either.  */
2334       if (!DECL_ARTIFICIAL (decl))
2335 	init = instantiate_non_dependent_or_null (init);
2336       if (!init
2337 	  || !TREE_TYPE (init)
2338 	  || !TREE_CONSTANT (init)
2339 	  || (!return_aggregate_cst_ok_p
2340 	      /* Unless RETURN_AGGREGATE_CST_OK_P is true, do not
2341 		 return an aggregate constant (of which string
2342 		 literals are a special case), as we do not want
2343 		 to make inadvertent copies of such entities, and
2344 		 we must be sure that their addresses are the
2345  		 same everywhere.  */
2346 	      && (TREE_CODE (init) == CONSTRUCTOR
2347 		  || TREE_CODE (init) == STRING_CST)))
2348 	break;
2349       /* Don't return a CONSTRUCTOR for a variable with partial run-time
2350 	 initialization, since it doesn't represent the entire value.
2351 	 Similarly for VECTOR_CSTs created by cp_folding those
2352 	 CONSTRUCTORs.  */
2353       if ((TREE_CODE (init) == CONSTRUCTOR
2354 	   || TREE_CODE (init) == VECTOR_CST)
2355 	  && !DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
2356 	break;
2357       /* If the variable has a dynamic initializer, don't use its
2358 	 DECL_INITIAL which doesn't reflect the real value.  */
2359       if (VAR_P (decl)
2360 	  && TREE_STATIC (decl)
2361 	  && !DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)
2362 	  && DECL_NONTRIVIALLY_INITIALIZED_P (decl))
2363 	break;
2364       decl = unshare_expr (init);
2365     }
2366   return decl;
2367 }
2368 
2369 /* If DECL is a CONST_DECL, or a constant VAR_DECL initialized by constant
2370    of integral or enumeration type, or a constexpr variable of scalar type,
2371    then return that value.  These are those variables permitted in constant
2372    expressions by [5.19/1].  */
2373 
2374 tree
scalar_constant_value(tree decl)2375 scalar_constant_value (tree decl)
2376 {
2377   return constant_value_1 (decl, /*strict_p=*/true,
2378 			   /*return_aggregate_cst_ok_p=*/false);
2379 }
2380 
2381 /* Like scalar_constant_value, but can also return aggregate initializers.  */
2382 
2383 tree
decl_really_constant_value(tree decl)2384 decl_really_constant_value (tree decl)
2385 {
2386   return constant_value_1 (decl, /*strict_p=*/true,
2387 			   /*return_aggregate_cst_ok_p=*/true);
2388 }
2389 
2390 /* A more relaxed version of scalar_constant_value, used by the
2391    common C/C++ code.  */
2392 
2393 tree
decl_constant_value(tree decl)2394 decl_constant_value (tree decl)
2395 {
2396   return constant_value_1 (decl, /*strict_p=*/processing_template_decl,
2397 			   /*return_aggregate_cst_ok_p=*/true);
2398 }
2399 
2400 /* Common subroutines of build_new and build_vec_delete.  */
2401 
2402 /* Build and return a NEW_EXPR.  If NELTS is non-NULL, TYPE[NELTS] is
2403    the type of the object being allocated; otherwise, it's just TYPE.
2404    INIT is the initializer, if any.  USE_GLOBAL_NEW is true if the
2405    user explicitly wrote "::operator new".  PLACEMENT, if non-NULL, is
2406    a vector of arguments to be provided as arguments to a placement
2407    new operator.  This routine performs no semantic checks; it just
2408    creates and returns a NEW_EXPR.  */
2409 
2410 static tree
build_raw_new_expr(vec<tree,va_gc> * placement,tree type,tree nelts,vec<tree,va_gc> * init,int use_global_new)2411 build_raw_new_expr (vec<tree, va_gc> *placement, tree type, tree nelts,
2412 		    vec<tree, va_gc> *init, int use_global_new)
2413 {
2414   tree init_list;
2415   tree new_expr;
2416 
2417   /* If INIT is NULL, the we want to store NULL_TREE in the NEW_EXPR.
2418      If INIT is not NULL, then we want to store VOID_ZERO_NODE.  This
2419      permits us to distinguish the case of a missing initializer "new
2420      int" from an empty initializer "new int()".  */
2421   if (init == NULL)
2422     init_list = NULL_TREE;
2423   else if (init->is_empty ())
2424     init_list = void_node;
2425   else
2426     init_list = build_tree_list_vec (init);
2427 
2428   new_expr = build4 (NEW_EXPR, build_pointer_type (type),
2429 		     build_tree_list_vec (placement), type, nelts,
2430 		     init_list);
2431   NEW_EXPR_USE_GLOBAL (new_expr) = use_global_new;
2432   TREE_SIDE_EFFECTS (new_expr) = 1;
2433 
2434   return new_expr;
2435 }
2436 
2437 /* Diagnose uninitialized const members or reference members of type
2438    TYPE. USING_NEW is used to disambiguate the diagnostic between a
2439    new expression without a new-initializer and a declaration. Returns
2440    the error count. */
2441 
2442 static int
diagnose_uninitialized_cst_or_ref_member_1(tree type,tree origin,bool using_new,bool complain)2443 diagnose_uninitialized_cst_or_ref_member_1 (tree type, tree origin,
2444 					    bool using_new, bool complain)
2445 {
2446   tree field;
2447   int error_count = 0;
2448 
2449   if (type_has_user_provided_constructor (type))
2450     return 0;
2451 
2452   for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
2453     {
2454       tree field_type;
2455 
2456       if (TREE_CODE (field) != FIELD_DECL)
2457 	continue;
2458 
2459       field_type = strip_array_types (TREE_TYPE (field));
2460 
2461       if (type_has_user_provided_constructor (field_type))
2462 	continue;
2463 
2464       if (TYPE_REF_P (field_type))
2465 	{
2466 	  ++ error_count;
2467 	  if (complain)
2468 	    {
2469 	      if (DECL_CONTEXT (field) == origin)
2470 		{
2471 		  if (using_new)
2472 		    error ("uninitialized reference member in %q#T "
2473 			   "using %<new%> without new-initializer", origin);
2474 		  else
2475 		    error ("uninitialized reference member in %q#T", origin);
2476 		}
2477 	      else
2478 		{
2479 		  if (using_new)
2480 		    error ("uninitialized reference member in base %q#T "
2481 			   "of %q#T using %<new%> without new-initializer",
2482 			   DECL_CONTEXT (field), origin);
2483 		  else
2484 		    error ("uninitialized reference member in base %q#T "
2485 			   "of %q#T", DECL_CONTEXT (field), origin);
2486 		}
2487 	      inform (DECL_SOURCE_LOCATION (field),
2488 		      "%q#D should be initialized", field);
2489 	    }
2490 	}
2491 
2492       if (CP_TYPE_CONST_P (field_type))
2493 	{
2494 	  ++ error_count;
2495 	  if (complain)
2496 	    {
2497 	      if (DECL_CONTEXT (field) == origin)
2498 		{
2499 		  if (using_new)
2500 		    error ("uninitialized const member in %q#T "
2501 			   "using %<new%> without new-initializer", origin);
2502 		  else
2503 		    error ("uninitialized const member in %q#T", origin);
2504 		}
2505 	      else
2506 		{
2507 		  if (using_new)
2508 		    error ("uninitialized const member in base %q#T "
2509 			   "of %q#T using %<new%> without new-initializer",
2510 			   DECL_CONTEXT (field), origin);
2511 		  else
2512 		    error ("uninitialized const member in base %q#T "
2513 			   "of %q#T", DECL_CONTEXT (field), origin);
2514 		}
2515 	      inform (DECL_SOURCE_LOCATION (field),
2516 		      "%q#D should be initialized", field);
2517 	    }
2518 	}
2519 
2520       if (CLASS_TYPE_P (field_type))
2521 	error_count
2522 	  += diagnose_uninitialized_cst_or_ref_member_1 (field_type, origin,
2523 							 using_new, complain);
2524     }
2525   return error_count;
2526 }
2527 
2528 int
diagnose_uninitialized_cst_or_ref_member(tree type,bool using_new,bool complain)2529 diagnose_uninitialized_cst_or_ref_member (tree type, bool using_new, bool complain)
2530 {
2531   return diagnose_uninitialized_cst_or_ref_member_1 (type, type, using_new, complain);
2532 }
2533 
2534 /* Call __cxa_bad_array_new_length to indicate that the size calculation
2535    overflowed.  Pretend it returns sizetype so that it plays nicely in the
2536    COND_EXPR.  */
2537 
2538 tree
throw_bad_array_new_length(void)2539 throw_bad_array_new_length (void)
2540 {
2541   if (!fn)
2542     {
2543       tree name = get_identifier ("__cxa_throw_bad_array_new_length");
2544 
2545       fn = get_global_binding (name);
2546       if (!fn)
2547 	fn = push_throw_library_fn
2548 	  (name, build_function_type_list (sizetype, NULL_TREE));
2549     }
2550 
2551   return build_cxx_call (fn, 0, NULL, tf_warning_or_error);
2552 }
2553 
2554 /* Attempt to find the initializer for flexible array field T in the
2555    initializer INIT, when non-null.  Returns the initializer when
2556    successful and NULL otherwise.  */
2557 static tree
find_flexarray_init(tree t,tree init)2558 find_flexarray_init (tree t, tree init)
2559 {
2560   if (!init || init == error_mark_node)
2561     return NULL_TREE;
2562 
2563   unsigned HOST_WIDE_INT idx;
2564   tree field, elt;
2565 
2566   /* Iterate over all top-level initializer elements.  */
2567   FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init), idx, field, elt)
2568     /* If the member T is found, return it.  */
2569     if (field == t)
2570       return elt;
2571 
2572   return NULL_TREE;
2573 }
2574 
2575 /* Attempt to verify that the argument, OPER, of a placement new expression
2576    refers to an object sufficiently large for an object of TYPE or an array
2577    of NELTS of such objects when NELTS is non-null, and issue a warning when
2578    it does not.  SIZE specifies the size needed to construct the object or
2579    array and captures the result of NELTS * sizeof (TYPE). (SIZE could be
2580    greater when the array under construction requires a cookie to store
2581    NELTS.  GCC's placement new expression stores the cookie when invoking
2582    a user-defined placement new operator function but not the default one.
2583    Placement new expressions with user-defined placement new operator are
2584    not diagnosed since we don't know how they use the buffer (this could
2585    be a future extension).  */
2586 static void
warn_placement_new_too_small(tree type,tree nelts,tree size,tree oper)2587 warn_placement_new_too_small (tree type, tree nelts, tree size, tree oper)
2588 {
2589   location_t loc = cp_expr_loc_or_loc (oper, input_location);
2590 
2591   /* The number of bytes to add to or subtract from the size of the provided
2592      buffer based on an offset into an array or an array element reference.
2593      Although intermediate results may be negative (as in a[3] - 2) a valid
2594      final result cannot be.  */
2595   offset_int adjust = 0;
2596   /* True when the size of the entire destination object should be used
2597      to compute the possibly optimistic estimate of the available space.  */
2598   bool use_obj_size = false;
2599   /* True when the reference to the destination buffer is an ADDR_EXPR.  */
2600   bool addr_expr = false;
2601 
2602   STRIP_NOPS (oper);
2603 
2604   /* Using a function argument or a (non-array) variable as an argument
2605      to placement new is not checked since it's unknown what it might
2606      point to.  */
2607   if (TREE_CODE (oper) == PARM_DECL
2608       || VAR_P (oper)
2609       || TREE_CODE (oper) == COMPONENT_REF)
2610     return;
2611 
2612   /* Evaluate any constant expressions.  */
2613   size = fold_non_dependent_expr (size);
2614 
2615   /* Handle the common case of array + offset expression when the offset
2616      is a constant.  */
2617   if (TREE_CODE (oper) == POINTER_PLUS_EXPR)
2618     {
2619       /* If the offset is compile-time constant, use it to compute a more
2620 	 accurate estimate of the size of the buffer.  Since the operand
2621 	 of POINTER_PLUS_EXPR is represented as an unsigned type, convert
2622 	 it to signed first.
2623 	 Otherwise, use the size of the entire array as an optimistic
2624 	 estimate (this may lead to false negatives).  */
2625       tree adj = TREE_OPERAND (oper, 1);
2626       adj = fold_for_warn (adj);
2627       if (CONSTANT_CLASS_P (adj))
2628 	adjust += wi::to_offset (convert (ssizetype, adj));
2629       else
2630 	use_obj_size = true;
2631 
2632       oper = TREE_OPERAND (oper, 0);
2633 
2634       STRIP_NOPS (oper);
2635     }
2636 
2637   if (TREE_CODE (oper) == TARGET_EXPR)
2638     oper = TREE_OPERAND (oper, 1);
2639   else if (TREE_CODE (oper) == ADDR_EXPR)
2640     {
2641       addr_expr = true;
2642       oper = TREE_OPERAND (oper, 0);
2643     }
2644 
2645   STRIP_NOPS (oper);
2646 
2647   if (TREE_CODE (oper) == ARRAY_REF
2648       && (addr_expr || TREE_CODE (TREE_TYPE (oper)) == ARRAY_TYPE))
2649     {
2650       /* Similar to the offset computed above, see if the array index
2651 	 is a compile-time constant.  If so, and unless the offset was
2652 	 not a compile-time constant, use the index to determine the
2653 	 size of the buffer.  Otherwise, use the entire array as
2654 	 an optimistic estimate of the size.  */
2655       const_tree adj = fold_non_dependent_expr (TREE_OPERAND (oper, 1));
2656       if (!use_obj_size && CONSTANT_CLASS_P (adj))
2657 	adjust += wi::to_offset (adj);
2658       else
2659 	{
2660 	  use_obj_size = true;
2661 	  adjust = 0;
2662 	}
2663 
2664       oper = TREE_OPERAND (oper, 0);
2665     }
2666 
2667   /* Refers to the declared object that constains the subobject referenced
2668      by OPER.  When the object is initialized, makes it possible to determine
2669      the actual size of a flexible array member used as the buffer passed
2670      as OPER to placement new.  */
2671   tree var_decl = NULL_TREE;
2672   /* True when operand is a COMPONENT_REF, to distinguish flexible array
2673      members from arrays of unspecified size.  */
2674   bool compref = TREE_CODE (oper) == COMPONENT_REF;
2675 
2676   /* For COMPONENT_REF (i.e., a struct member) the size of the entire
2677      enclosing struct.  Used to validate the adjustment (offset) into
2678      an array at the end of a struct.  */
2679   offset_int compsize = 0;
2680 
2681   /* Descend into a struct or union to find the member whose address
2682      is being used as the argument.  */
2683   if (TREE_CODE (oper) == COMPONENT_REF)
2684     {
2685       tree comptype = TREE_TYPE (TREE_OPERAND (oper, 0));
2686       compsize = wi::to_offset (TYPE_SIZE_UNIT (comptype));
2687 
2688       tree op0 = oper;
2689       while (TREE_CODE (op0 = TREE_OPERAND (op0, 0)) == COMPONENT_REF);
2690       STRIP_ANY_LOCATION_WRAPPER (op0);
2691       if (VAR_P (op0))
2692 	var_decl = op0;
2693       oper = TREE_OPERAND (oper, 1);
2694     }
2695 
2696   STRIP_ANY_LOCATION_WRAPPER (oper);
2697   tree opertype = TREE_TYPE (oper);
2698   if ((addr_expr || !INDIRECT_TYPE_P (opertype))
2699       && (VAR_P (oper)
2700 	  || TREE_CODE (oper) == FIELD_DECL
2701 	  || TREE_CODE (oper) == PARM_DECL))
2702     {
2703       /* A possibly optimistic estimate of the number of bytes available
2704 	 in the destination buffer.  */
2705       offset_int bytes_avail = 0;
2706       /* True when the estimate above is in fact the exact size
2707 	 of the destination buffer rather than an estimate.  */
2708       bool exact_size = true;
2709 
2710       /* Treat members of unions and members of structs uniformly, even
2711 	 though the size of a member of a union may be viewed as extending
2712 	 to the end of the union itself (it is by __builtin_object_size).  */
2713       if ((VAR_P (oper) || use_obj_size)
2714 	  && DECL_SIZE_UNIT (oper)
2715 	  && tree_fits_uhwi_p (DECL_SIZE_UNIT (oper)))
2716 	{
2717 	  /* Use the size of the entire array object when the expression
2718 	     refers to a variable or its size depends on an expression
2719 	     that's not a compile-time constant.  */
2720 	  bytes_avail = wi::to_offset (DECL_SIZE_UNIT (oper));
2721 	  exact_size = !use_obj_size;
2722 	}
2723       else if (tree opersize = TYPE_SIZE_UNIT (opertype))
2724 	{
2725 	  /* Use the size of the type of the destination buffer object
2726 	     as the optimistic estimate of the available space in it.
2727 	     Use the maximum possible size for zero-size arrays and
2728 	     flexible array members (except of initialized objects
2729 	     thereof).  */
2730 	  if (TREE_CODE (opersize) == INTEGER_CST)
2731 	    bytes_avail = wi::to_offset (opersize);
2732 	}
2733 
2734       if (bytes_avail == 0)
2735 	{
2736 	  if (var_decl)
2737 	    {
2738 	      /* Constructing into a buffer provided by the flexible array
2739 		 member of a declared object (which is permitted as a G++
2740 		 extension).  If the array member has been initialized,
2741 		 determine its size from the initializer.  Otherwise,
2742 		 the array size is zero.  */
2743 	      if (tree init = find_flexarray_init (oper,
2744 						   DECL_INITIAL (var_decl)))
2745 		bytes_avail = wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (init)));
2746 	    }
2747 	  else
2748 	    bytes_avail = (wi::to_offset (TYPE_MAX_VALUE (ptrdiff_type_node))
2749 			   - compsize);
2750 	}
2751 
2752       tree_code oper_code = TREE_CODE (opertype);
2753 
2754       if (compref && oper_code == ARRAY_TYPE)
2755 	{
2756 	  tree nelts = array_type_nelts_top (opertype);
2757 	  tree nelts_cst = maybe_constant_value (nelts);
2758 	  if (TREE_CODE (nelts_cst) == INTEGER_CST
2759 	      && integer_onep (nelts_cst)
2760 	      && !var_decl
2761 	      && warn_placement_new < 2)
2762 	    return;
2763 	}
2764 
2765       /* Reduce the size of the buffer by the adjustment computed above
2766 	 from the offset and/or the index into the array.  */
2767       if (bytes_avail < adjust || adjust < 0)
2768 	bytes_avail = 0;
2769       else
2770 	{
2771 	  tree elttype = (TREE_CODE (opertype) == ARRAY_TYPE
2772 			  ? TREE_TYPE (opertype) : opertype);
2773 	  if (tree eltsize = TYPE_SIZE_UNIT (elttype))
2774 	    {
2775 	      bytes_avail -= adjust * wi::to_offset (eltsize);
2776 	      if (bytes_avail < 0)
2777 		bytes_avail = 0;
2778 	    }
2779 	}
2780 
2781       /* The minimum amount of space needed for the allocation.  This
2782 	 is an optimistic estimate that makes it possible to detect
2783 	 placement new invocation for some undersize buffers but not
2784 	 others.  */
2785       offset_int bytes_need;
2786 
2787       if (nelts)
2788 	nelts = fold_for_warn (nelts);
2789 
2790       if (CONSTANT_CLASS_P (size))
2791 	bytes_need = wi::to_offset (size);
2792       else if (nelts && CONSTANT_CLASS_P (nelts))
2793 	bytes_need = (wi::to_offset (nelts)
2794 		      * wi::to_offset (TYPE_SIZE_UNIT (type)));
2795       else if (tree_fits_uhwi_p (TYPE_SIZE_UNIT (type)))
2796 	bytes_need = wi::to_offset (TYPE_SIZE_UNIT (type));
2797       else
2798 	{
2799 	  /* The type is a VLA.  */
2800 	  return;
2801 	}
2802 
2803       if (bytes_avail < bytes_need)
2804 	{
2805 	  if (nelts)
2806 	    if (CONSTANT_CLASS_P (nelts))
2807 	      warning_at (loc, OPT_Wplacement_new_,
2808 			  exact_size ?
2809 			  "placement new constructing an object of type "
2810 			  "%<%T [%wu]%> and size %qwu in a region of type %qT "
2811 			  "and size %qwi"
2812 			  : "placement new constructing an object of type "
2813 			  "%<%T [%wu]%> and size %qwu in a region of type %qT "
2814 			  "and size at most %qwu",
2815 			  type, tree_to_uhwi (nelts), bytes_need.to_uhwi (),
2816 			  opertype, bytes_avail.to_uhwi ());
2817 	    else
2818 	      warning_at (loc, OPT_Wplacement_new_,
2819 			  exact_size ?
2820 			  "placement new constructing an array of objects "
2821 			  "of type %qT and size %qwu in a region of type %qT "
2822 			  "and size %qwi"
2823 			  : "placement new constructing an array of objects "
2824 			  "of type %qT and size %qwu in a region of type %qT "
2825 			  "and size at most %qwu",
2826 			  type, bytes_need.to_uhwi (), opertype,
2827 			  bytes_avail.to_uhwi ());
2828 	  else
2829 	    warning_at (loc, OPT_Wplacement_new_,
2830 			exact_size ?
2831 			"placement new constructing an object of type %qT "
2832 			"and size %qwu in a region of type %qT and size %qwi"
2833 			: "placement new constructing an object of type %qT "
2834 			"and size %qwu in a region of type %qT and size "
2835 			"at most %qwu",
2836 			type, bytes_need.to_uhwi (), opertype,
2837 			bytes_avail.to_uhwi ());
2838 	}
2839     }
2840 }
2841 
2842 /* True if alignof(T) > __STDCPP_DEFAULT_NEW_ALIGNMENT__.  */
2843 
2844 bool
type_has_new_extended_alignment(tree t)2845 type_has_new_extended_alignment (tree t)
2846 {
2847   return (aligned_new_threshold
2848 	  && TYPE_ALIGN_UNIT (t) > (unsigned)aligned_new_threshold);
2849 }
2850 
2851 /* Return the alignment we expect malloc to guarantee.  This should just be
2852    MALLOC_ABI_ALIGNMENT, but that macro defaults to only BITS_PER_WORD for some
2853    reason, so don't let the threshold be smaller than max_align_t_align.  */
2854 
2855 unsigned
malloc_alignment()2856 malloc_alignment ()
2857 {
2858   return MAX (max_align_t_align(), MALLOC_ABI_ALIGNMENT);
2859 }
2860 
2861 /* Determine whether an allocation function is a namespace-scope
2862    non-replaceable placement new function. See DR 1748.
2863    TODO: Enable in all standard modes.  */
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 /* Generate code for a new-expression, including calling the "operator
2878    new" function, initializing the object, and, if an exception occurs
2879    during construction, cleaning up.  The arguments are as for
2880    build_raw_new_expr.  This may change PLACEMENT and INIT.
2881    TYPE is the type of the object being constructed, possibly an array
2882    of NELTS elements when NELTS is non-null (in "new T[NELTS]", T may
2883    be an array of the form U[inner], with the whole expression being
2884    "new U[NELTS][inner]").  */
2885 
2886 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)2887 build_new_1 (vec<tree, va_gc> **placement, tree type, tree nelts,
2888 	     vec<tree, va_gc> **init, bool globally_qualified_p,
2889 	     tsubst_flags_t complain)
2890 {
2891   tree size, rval;
2892   /* True iff this is a call to "operator new[]" instead of just
2893      "operator new".  */
2894   bool array_p = false;
2895   /* If ARRAY_P is true, the element type of the array.  This is never
2896      an ARRAY_TYPE; for something like "new int[3][4]", the
2897      ELT_TYPE is "int".  If ARRAY_P is false, this is the same type as
2898      TYPE.  */
2899   tree elt_type;
2900   /* The type of the new-expression.  (This type is always a pointer
2901      type.)  */
2902   tree pointer_type;
2903   tree non_const_pointer_type;
2904   /* The most significant array bound in int[OUTER_NELTS][inner].  */
2905   tree outer_nelts = NULL_TREE;
2906   /* For arrays with a non-constant number of elements, a bounds checks
2907      on the NELTS parameter to avoid integer overflow at runtime. */
2908   tree outer_nelts_check = NULL_TREE;
2909   bool outer_nelts_from_type = false;
2910   /* Number of the "inner" elements in "new T[OUTER_NELTS][inner]".  */
2911   offset_int inner_nelts_count = 1;
2912   tree alloc_call, alloc_expr;
2913   /* Size of the inner array elements (those with constant dimensions). */
2914   offset_int inner_size;
2915   /* The address returned by the call to "operator new".  This node is
2916      a VAR_DECL and is therefore reusable.  */
2917   tree alloc_node;
2918   tree alloc_fn;
2919   tree cookie_expr, init_expr;
2920   int nothrow, check_new;
2921   /* If non-NULL, the number of extra bytes to allocate at the
2922      beginning of the storage allocated for an array-new expression in
2923      order to store the number of elements.  */
2924   tree cookie_size = NULL_TREE;
2925   tree placement_first;
2926   tree placement_expr = NULL_TREE;
2927   /* True if the function we are calling is a placement allocation
2928      function.  */
2929   bool placement_allocation_fn_p;
2930   /* True if the storage must be initialized, either by a constructor
2931      or due to an explicit new-initializer.  */
2932   bool is_initialized;
2933   /* The address of the thing allocated, not including any cookie.  In
2934      particular, if an array cookie is in use, DATA_ADDR is the
2935      address of the first array element.  This node is a VAR_DECL, and
2936      is therefore reusable.  */
2937   tree data_addr;
2938   tree init_preeval_expr = NULL_TREE;
2939   tree orig_type = type;
2940 
2941   if (nelts)
2942     {
2943       outer_nelts = nelts;
2944       array_p = true;
2945     }
2946   else if (TREE_CODE (type) == ARRAY_TYPE)
2947     {
2948       /* Transforms new (T[N]) to new T[N].  The former is a GNU
2949 	 extension for variable N.  (This also covers new T where T is
2950 	 a VLA typedef.)  */
2951       array_p = true;
2952       nelts = array_type_nelts_top (type);
2953       outer_nelts = nelts;
2954       type = TREE_TYPE (type);
2955       outer_nelts_from_type = true;
2956     }
2957 
2958   /* Lots of logic below depends on whether we have a constant number of
2959      elements, so go ahead and fold it now.  */
2960   const_tree cst_outer_nelts = fold_non_dependent_expr (outer_nelts, complain);
2961 
2962   /* If our base type is an array, then make sure we know how many elements
2963      it has.  */
2964   for (elt_type = type;
2965        TREE_CODE (elt_type) == ARRAY_TYPE;
2966        elt_type = TREE_TYPE (elt_type))
2967     {
2968       tree inner_nelts = array_type_nelts_top (elt_type);
2969       tree inner_nelts_cst = maybe_constant_value (inner_nelts);
2970       if (TREE_CODE (inner_nelts_cst) == INTEGER_CST)
2971 	{
2972 	  wi::overflow_type overflow;
2973 	  offset_int result = wi::mul (wi::to_offset (inner_nelts_cst),
2974 				       inner_nelts_count, SIGNED, &overflow);
2975 	  if (overflow)
2976 	    {
2977 	      if (complain & tf_error)
2978 		error ("integer overflow in array size");
2979 	      nelts = error_mark_node;
2980 	    }
2981 	  inner_nelts_count = result;
2982 	}
2983       else
2984 	{
2985 	  if (complain & tf_error)
2986 	    {
2987 	      error_at (cp_expr_loc_or_loc (inner_nelts, input_location),
2988 			"array size in new-expression must be constant");
2989 	      cxx_constant_value(inner_nelts);
2990 	    }
2991 	  nelts = error_mark_node;
2992 	}
2993       if (nelts != error_mark_node)
2994 	nelts = cp_build_binary_op (input_location,
2995 				    MULT_EXPR, nelts,
2996 				    inner_nelts_cst,
2997 				    complain);
2998     }
2999 
3000   if (variably_modified_type_p (elt_type, NULL_TREE) && (complain & tf_error))
3001     {
3002       error ("variably modified type not allowed in new-expression");
3003       return error_mark_node;
3004     }
3005 
3006   if (nelts == error_mark_node)
3007     return error_mark_node;
3008 
3009   /* Warn if we performed the (T[N]) to T[N] transformation and N is
3010      variable.  */
3011   if (outer_nelts_from_type
3012       && !TREE_CONSTANT (cst_outer_nelts))
3013     {
3014       if (complain & tf_warning_or_error)
3015 	{
3016 	  pedwarn (cp_expr_loc_or_loc (outer_nelts, input_location), OPT_Wvla,
3017 		   typedef_variant_p (orig_type)
3018 		   ? G_("non-constant array new length must be specified "
3019 			"directly, not by typedef")
3020 		   : G_("non-constant array new length must be specified "
3021 			"without parentheses around the type-id"));
3022 	}
3023       else
3024 	return error_mark_node;
3025     }
3026 
3027   if (VOID_TYPE_P (elt_type))
3028     {
3029       if (complain & tf_error)
3030         error ("invalid type %<void%> for new");
3031       return error_mark_node;
3032     }
3033 
3034   if (is_std_init_list (elt_type))
3035     warning (OPT_Winit_list_lifetime,
3036 	     "%<new%> of initializer_list does not "
3037 	     "extend the lifetime of the underlying array");
3038 
3039   if (abstract_virtuals_error_sfinae (ACU_NEW, elt_type, complain))
3040     return error_mark_node;
3041 
3042   is_initialized = (type_build_ctor_call (elt_type) || *init != NULL);
3043 
3044   if (*init == NULL && cxx_dialect < cxx11)
3045     {
3046       bool maybe_uninitialized_error = false;
3047       /* A program that calls for default-initialization [...] of an
3048 	 entity of reference type is ill-formed. */
3049       if (CLASSTYPE_REF_FIELDS_NEED_INIT (elt_type))
3050 	maybe_uninitialized_error = true;
3051 
3052       /* A new-expression that creates an object of type T initializes
3053 	 that object as follows:
3054       - If the new-initializer is omitted:
3055         -- If T is a (possibly cv-qualified) non-POD class type
3056 	   (or array thereof), the object is default-initialized (8.5).
3057 	   [...]
3058         -- Otherwise, the object created has indeterminate
3059 	   value. If T is a const-qualified type, or a (possibly
3060 	   cv-qualified) POD class type (or array thereof)
3061 	   containing (directly or indirectly) a member of
3062 	   const-qualified type, the program is ill-formed; */
3063 
3064       if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (elt_type))
3065 	maybe_uninitialized_error = true;
3066 
3067       if (maybe_uninitialized_error
3068 	  && diagnose_uninitialized_cst_or_ref_member (elt_type,
3069 						       /*using_new=*/true,
3070 						       complain & tf_error))
3071 	return error_mark_node;
3072     }
3073 
3074   if (CP_TYPE_CONST_P (elt_type) && *init == NULL
3075       && default_init_uninitialized_part (elt_type))
3076     {
3077       if (complain & tf_error)
3078         error ("uninitialized const in %<new%> of %q#T", elt_type);
3079       return error_mark_node;
3080     }
3081 
3082   size = size_in_bytes (elt_type);
3083   if (array_p)
3084     {
3085       /* Maximum available size in bytes.  Half of the address space
3086 	 minus the cookie size.  */
3087       offset_int max_size
3088 	= wi::set_bit_in_zero <offset_int> (TYPE_PRECISION (sizetype) - 1);
3089       /* Maximum number of outer elements which can be allocated. */
3090       offset_int max_outer_nelts;
3091       tree max_outer_nelts_tree;
3092 
3093       gcc_assert (TREE_CODE (size) == INTEGER_CST);
3094       cookie_size = targetm.cxx.get_cookie_size (elt_type);
3095       gcc_assert (TREE_CODE (cookie_size) == INTEGER_CST);
3096       gcc_checking_assert (wi::ltu_p (wi::to_offset (cookie_size), max_size));
3097       /* Unconditionally subtract the cookie size.  This decreases the
3098 	 maximum object size and is safe even if we choose not to use
3099 	 a cookie after all.  */
3100       max_size -= wi::to_offset (cookie_size);
3101       wi::overflow_type overflow;
3102       inner_size = wi::mul (wi::to_offset (size), inner_nelts_count, SIGNED,
3103 			    &overflow);
3104       if (overflow || wi::gtu_p (inner_size, max_size))
3105 	{
3106 	  if (complain & tf_error)
3107 	    {
3108 	      cst_size_error error;
3109 	      if (overflow)
3110 		error = cst_size_overflow;
3111 	      else
3112 		{
3113 		  error = cst_size_too_big;
3114 		  size = size_binop (MULT_EXPR, size,
3115 				     wide_int_to_tree (sizetype,
3116 						       inner_nelts_count));
3117 		  size = cp_fully_fold (size);
3118 		}
3119 	      invalid_array_size_error (input_location, error, size,
3120 					/*name=*/NULL_TREE);
3121 	    }
3122 	  return error_mark_node;
3123 	}
3124 
3125       max_outer_nelts = wi::udiv_trunc (max_size, inner_size);
3126       max_outer_nelts_tree = wide_int_to_tree (sizetype, max_outer_nelts);
3127 
3128       size = size_binop (MULT_EXPR, size, fold_convert (sizetype, nelts));
3129 
3130       if (TREE_CODE (cst_outer_nelts) == INTEGER_CST)
3131 	{
3132 	  if (tree_int_cst_lt (max_outer_nelts_tree, cst_outer_nelts))
3133 	    {
3134 	      /* When the array size is constant, check it at compile time
3135 		 to make sure it doesn't exceed the implementation-defined
3136 		 maximum, as required by C++ 14 (in C++ 11 this requirement
3137 		 isn't explicitly stated but it's enforced anyway -- see
3138 		 grokdeclarator in cp/decl.c).  */
3139 	      if (complain & tf_error)
3140 		{
3141 		  size = cp_fully_fold (size);
3142 		  invalid_array_size_error (input_location, cst_size_too_big,
3143 					    size, NULL_TREE);
3144 		}
3145 	      return error_mark_node;
3146 	    }
3147 	}
3148       else
3149  	{
3150 	  /* When a runtime check is necessary because the array size
3151 	     isn't constant, keep only the top-most seven bits (starting
3152 	     with the most significant non-zero bit) of the maximum size
3153 	     to compare the array size against, to simplify encoding the
3154 	     constant maximum size in the instruction stream.  */
3155 
3156 	  unsigned shift = (max_outer_nelts.get_precision ()) - 7
3157 	    - wi::clz (max_outer_nelts);
3158 	  max_outer_nelts = (max_outer_nelts >> shift) << shift;
3159 
3160           outer_nelts_check = fold_build2 (LE_EXPR, boolean_type_node,
3161 					   outer_nelts,
3162 					   max_outer_nelts_tree);
3163 	}
3164     }
3165 
3166   tree align_arg = NULL_TREE;
3167   if (type_has_new_extended_alignment (elt_type))
3168     align_arg = build_int_cst (align_type_node, TYPE_ALIGN_UNIT (elt_type));
3169 
3170   alloc_fn = NULL_TREE;
3171 
3172   /* If PLACEMENT is a single simple pointer type not passed by
3173      reference, prepare to capture it in a temporary variable.  Do
3174      this now, since PLACEMENT will change in the calls below.  */
3175   placement_first = NULL_TREE;
3176   if (vec_safe_length (*placement) == 1
3177       && (TYPE_PTR_P (TREE_TYPE ((**placement)[0]))))
3178     placement_first = (**placement)[0];
3179 
3180   bool member_new_p = false;
3181 
3182   /* Allocate the object.  */
3183   tree fnname;
3184   tree fns;
3185 
3186   fnname = ovl_op_identifier (false, array_p ? VEC_NEW_EXPR : NEW_EXPR);
3187 
3188   member_new_p = !globally_qualified_p
3189 		 && CLASS_TYPE_P (elt_type)
3190 		 && (array_p
3191 		     ? TYPE_HAS_ARRAY_NEW_OPERATOR (elt_type)
3192 		     : TYPE_HAS_NEW_OPERATOR (elt_type));
3193 
3194   if (member_new_p)
3195     {
3196       /* Use a class-specific operator new.  */
3197       /* If a cookie is required, add some extra space.  */
3198       if (array_p && TYPE_VEC_NEW_USES_COOKIE (elt_type))
3199 	size = size_binop (PLUS_EXPR, size, cookie_size);
3200       else
3201 	{
3202 	  cookie_size = NULL_TREE;
3203 	  /* No size arithmetic necessary, so the size check is
3204 	     not needed. */
3205 	  if (outer_nelts_check != NULL && inner_size == 1)
3206 	    outer_nelts_check = NULL_TREE;
3207 	}
3208       /* Perform the overflow check.  */
3209       tree errval = TYPE_MAX_VALUE (sizetype);
3210       if (cxx_dialect >= cxx11 && flag_exceptions)
3211 	errval = throw_bad_array_new_length ();
3212       if (outer_nelts_check != NULL_TREE)
3213 	size = fold_build3 (COND_EXPR, sizetype, outer_nelts_check,
3214 			    size, errval);
3215       /* Create the argument list.  */
3216       vec_safe_insert (*placement, 0, size);
3217       /* Do name-lookup to find the appropriate operator.  */
3218       fns = lookup_fnfields (elt_type, fnname, /*protect=*/2);
3219       if (fns == NULL_TREE)
3220 	{
3221 	  if (complain & tf_error)
3222 	    error ("no suitable %qD found in class %qT", fnname, elt_type);
3223 	  return error_mark_node;
3224 	}
3225       if (TREE_CODE (fns) == TREE_LIST)
3226 	{
3227 	  if (complain & tf_error)
3228 	    {
3229 	      error ("request for member %qD is ambiguous", fnname);
3230 	      print_candidates (fns);
3231 	    }
3232 	  return error_mark_node;
3233 	}
3234       tree dummy = build_dummy_object (elt_type);
3235       alloc_call = NULL_TREE;
3236       if (align_arg)
3237 	{
3238 	  vec<tree, va_gc> *align_args
3239 	    = vec_copy_and_insert (*placement, align_arg, 1);
3240 	  alloc_call
3241 	    = build_new_method_call (dummy, fns, &align_args,
3242 				     /*conversion_path=*/NULL_TREE,
3243 				     LOOKUP_NORMAL, &alloc_fn, tf_none);
3244 	  /* If no matching function is found and the allocated object type
3245 	     has new-extended alignment, the alignment argument is removed
3246 	     from the argument list, and overload resolution is performed
3247 	     again.  */
3248 	  if (alloc_call == error_mark_node)
3249 	    alloc_call = NULL_TREE;
3250 	}
3251       if (!alloc_call)
3252 	alloc_call = build_new_method_call (dummy, fns, placement,
3253 					    /*conversion_path=*/NULL_TREE,
3254 					    LOOKUP_NORMAL,
3255 					    &alloc_fn, complain);
3256     }
3257   else
3258     {
3259       /* Use a global operator new.  */
3260       /* See if a cookie might be required.  */
3261       if (!(array_p && TYPE_VEC_NEW_USES_COOKIE (elt_type)))
3262 	{
3263 	  cookie_size = NULL_TREE;
3264 	  /* No size arithmetic necessary, so the size check is
3265 	     not needed. */
3266 	  if (outer_nelts_check != NULL && inner_size == 1)
3267 	    outer_nelts_check = NULL_TREE;
3268 	}
3269 
3270       alloc_call = build_operator_new_call (fnname, placement,
3271 					    &size, &cookie_size,
3272 					    align_arg, outer_nelts_check,
3273 					    &alloc_fn, complain);
3274     }
3275 
3276   if (alloc_call == error_mark_node)
3277     return error_mark_node;
3278 
3279   gcc_assert (alloc_fn != NULL_TREE);
3280 
3281   /* Now, check to see if this function is actually a placement
3282      allocation function.  This can happen even when PLACEMENT is NULL
3283      because we might have something like:
3284 
3285        struct S { void* operator new (size_t, int i = 0); };
3286 
3287      A call to `new S' will get this allocation function, even though
3288      there is no explicit placement argument.  If there is more than
3289      one argument, or there are variable arguments, then this is a
3290      placement allocation function.  */
3291   placement_allocation_fn_p
3292     = (type_num_arguments (TREE_TYPE (alloc_fn)) > 1
3293        || varargs_function_p (alloc_fn));
3294 
3295   if (warn_aligned_new
3296       && !placement_allocation_fn_p
3297       && TYPE_ALIGN (elt_type) > malloc_alignment ()
3298       && (warn_aligned_new > 1
3299 	  || CP_DECL_CONTEXT (alloc_fn) == global_namespace)
3300       && !aligned_allocation_fn_p (alloc_fn))
3301     {
3302       auto_diagnostic_group d;
3303       if (warning (OPT_Waligned_new_, "%<new%> of type %qT with extended "
3304 		   "alignment %d", elt_type, TYPE_ALIGN_UNIT (elt_type)))
3305 	{
3306 	  inform (input_location, "uses %qD, which does not have an alignment "
3307 		  "parameter", alloc_fn);
3308 	  if (!aligned_new_threshold)
3309 	    inform (input_location, "use %<-faligned-new%> to enable C++17 "
3310 				    "over-aligned new support");
3311 	}
3312     }
3313 
3314   /* If we found a simple case of PLACEMENT_EXPR above, then copy it
3315      into a temporary variable.  */
3316   if (!processing_template_decl
3317       && TREE_CODE (alloc_call) == CALL_EXPR
3318       && call_expr_nargs (alloc_call) == 2
3319       && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (alloc_call, 0))) == INTEGER_TYPE
3320       && TYPE_PTR_P (TREE_TYPE (CALL_EXPR_ARG (alloc_call, 1))))
3321     {
3322       tree placement = CALL_EXPR_ARG (alloc_call, 1);
3323 
3324       if (placement_first != NULL_TREE
3325 	  && (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (TREE_TYPE (placement)))
3326 	      || VOID_TYPE_P (TREE_TYPE (TREE_TYPE (placement)))))
3327 	{
3328 	  placement_expr = get_target_expr (placement_first);
3329 	  CALL_EXPR_ARG (alloc_call, 1)
3330 	    = fold_convert (TREE_TYPE (placement), placement_expr);
3331 	}
3332 
3333       if (!member_new_p
3334 	  && VOID_TYPE_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_ARG (alloc_call, 1)))))
3335 	{
3336 	  /* Attempt to make the warning point at the operator new argument.  */
3337 	  if (placement_first)
3338 	    placement = placement_first;
3339 
3340 	  warn_placement_new_too_small (orig_type, nelts, size, placement);
3341 	}
3342     }
3343 
3344   /* In the simple case, we can stop now.  */
3345   pointer_type = build_pointer_type (type);
3346   if (!cookie_size && !is_initialized)
3347     return build_nop (pointer_type, alloc_call);
3348 
3349   /* Store the result of the allocation call in a variable so that we can
3350      use it more than once.  */
3351   alloc_expr = get_target_expr (alloc_call);
3352   alloc_node = TARGET_EXPR_SLOT (alloc_expr);
3353 
3354   /* Strip any COMPOUND_EXPRs from ALLOC_CALL.  */
3355   while (TREE_CODE (alloc_call) == COMPOUND_EXPR)
3356     alloc_call = TREE_OPERAND (alloc_call, 1);
3357 
3358   /* Preevaluate the placement args so that we don't reevaluate them for a
3359      placement delete.  */
3360   if (placement_allocation_fn_p)
3361     {
3362       tree inits;
3363       stabilize_call (alloc_call, &inits);
3364       if (inits)
3365 	alloc_expr = build2 (COMPOUND_EXPR, TREE_TYPE (alloc_expr), inits,
3366 			     alloc_expr);
3367     }
3368 
3369   /*        unless an allocation function is declared with an empty  excep-
3370      tion-specification  (_except.spec_),  throw(), it indicates failure to
3371      allocate storage by throwing a bad_alloc exception  (clause  _except_,
3372      _lib.bad.alloc_); it returns a non-null pointer otherwise If the allo-
3373      cation function is declared  with  an  empty  exception-specification,
3374      throw(), it returns null to indicate failure to allocate storage and a
3375      non-null pointer otherwise.
3376 
3377      So check for a null exception spec on the op new we just called.  */
3378 
3379   nothrow = TYPE_NOTHROW_P (TREE_TYPE (alloc_fn));
3380   check_new
3381     = flag_check_new || (nothrow && !std_placement_new_fn_p (alloc_fn));
3382 
3383   if (cookie_size)
3384     {
3385       tree cookie;
3386       tree cookie_ptr;
3387       tree size_ptr_type;
3388 
3389       /* Adjust so we're pointing to the start of the object.  */
3390       data_addr = fold_build_pointer_plus (alloc_node, cookie_size);
3391 
3392       /* Store the number of bytes allocated so that we can know how
3393 	 many elements to destroy later.  We use the last sizeof
3394 	 (size_t) bytes to store the number of elements.  */
3395       cookie_ptr = size_binop (MINUS_EXPR, cookie_size, size_in_bytes (sizetype));
3396       cookie_ptr = fold_build_pointer_plus_loc (input_location,
3397 						alloc_node, cookie_ptr);
3398       size_ptr_type = build_pointer_type (sizetype);
3399       cookie_ptr = fold_convert (size_ptr_type, cookie_ptr);
3400       cookie = cp_build_fold_indirect_ref (cookie_ptr);
3401 
3402       cookie_expr = build2 (MODIFY_EXPR, sizetype, cookie, nelts);
3403 
3404       if (targetm.cxx.cookie_has_size ())
3405 	{
3406 	  /* Also store the element size.  */
3407 	  cookie_ptr = fold_build_pointer_plus (cookie_ptr,
3408 			       fold_build1_loc (input_location,
3409 						NEGATE_EXPR, sizetype,
3410 						size_in_bytes (sizetype)));
3411 
3412 	  cookie = cp_build_fold_indirect_ref (cookie_ptr);
3413 	  cookie = build2 (MODIFY_EXPR, sizetype, cookie,
3414 			   size_in_bytes (elt_type));
3415 	  cookie_expr = build2 (COMPOUND_EXPR, TREE_TYPE (cookie_expr),
3416 				cookie, cookie_expr);
3417 	}
3418     }
3419   else
3420     {
3421       cookie_expr = NULL_TREE;
3422       data_addr = alloc_node;
3423     }
3424 
3425   /* Now use a pointer to the type we've actually allocated.  */
3426 
3427   /* But we want to operate on a non-const version to start with,
3428      since we'll be modifying the elements.  */
3429   non_const_pointer_type = build_pointer_type
3430     (cp_build_qualified_type (type, cp_type_quals (type) & ~TYPE_QUAL_CONST));
3431 
3432   data_addr = fold_convert (non_const_pointer_type, data_addr);
3433   /* Any further uses of alloc_node will want this type, too.  */
3434   alloc_node = fold_convert (non_const_pointer_type, alloc_node);
3435 
3436   /* Now initialize the allocated object.  Note that we preevaluate the
3437      initialization expression, apart from the actual constructor call or
3438      assignment--we do this because we want to delay the allocation as long
3439      as possible in order to minimize the size of the exception region for
3440      placement delete.  */
3441   if (is_initialized)
3442     {
3443       bool stable;
3444       bool explicit_value_init_p = false;
3445 
3446       if (*init != NULL && (*init)->is_empty ())
3447 	{
3448 	  *init = NULL;
3449 	  explicit_value_init_p = true;
3450 	}
3451 
3452       if (processing_template_decl)
3453 	{
3454 	  /* Avoid an ICE when converting to a base in build_simple_base_path.
3455 	     We'll throw this all away anyway, and build_new will create
3456 	     a NEW_EXPR.  */
3457 	  tree t = fold_convert (build_pointer_type (elt_type), data_addr);
3458 	  /* build_value_init doesn't work in templates, and we don't need
3459 	     the initializer anyway since we're going to throw it away and
3460 	     rebuild it at instantiation time, so just build up a single
3461 	     constructor call to get any appropriate diagnostics.  */
3462 	  init_expr = cp_build_fold_indirect_ref (t);
3463 	  if (type_build_ctor_call (elt_type))
3464 	    init_expr = build_special_member_call (init_expr,
3465 						   complete_ctor_identifier,
3466 						   init, elt_type,
3467 						   LOOKUP_NORMAL,
3468 						   complain);
3469 	  stable = stabilize_init (init_expr, &init_preeval_expr);
3470 	}
3471       else if (array_p)
3472 	{
3473 	  tree vecinit = NULL_TREE;
3474 	  if (vec_safe_length (*init) == 1
3475 	      && DIRECT_LIST_INIT_P ((**init)[0]))
3476 	    {
3477 	      vecinit = (**init)[0];
3478 	      if (CONSTRUCTOR_NELTS (vecinit) == 0)
3479 		/* List-value-initialization, leave it alone.  */;
3480 	      else
3481 		{
3482 		  tree arraytype, domain;
3483 		  if (TREE_CONSTANT (nelts))
3484 		    domain = compute_array_index_type (NULL_TREE, nelts,
3485 						       complain);
3486 		  else
3487 		    /* We'll check the length at runtime.  */
3488 		    domain = NULL_TREE;
3489 		  arraytype = build_cplus_array_type (type, domain);
3490 		  vecinit = digest_init (arraytype, vecinit, complain);
3491 		}
3492 	    }
3493 	  else if (*init)
3494             {
3495               if (complain & tf_error)
3496                 error ("parenthesized initializer in array new");
3497 	      return error_mark_node;
3498             }
3499 	  init_expr
3500 	    = build_vec_init (data_addr,
3501 			      cp_build_binary_op (input_location,
3502 						  MINUS_EXPR, outer_nelts,
3503 						  integer_one_node,
3504 						  complain),
3505 			      vecinit,
3506 			      explicit_value_init_p,
3507 			      /*from_array=*/0,
3508                               complain);
3509 
3510 	  /* An array initialization is stable because the initialization
3511 	     of each element is a full-expression, so the temporaries don't
3512 	     leak out.  */
3513 	  stable = true;
3514 	}
3515       else
3516 	{
3517 	  init_expr = cp_build_fold_indirect_ref (data_addr);
3518 
3519 	  if (type_build_ctor_call (type) && !explicit_value_init_p)
3520 	    {
3521 	      init_expr = build_special_member_call (init_expr,
3522 						     complete_ctor_identifier,
3523 						     init, elt_type,
3524 						     LOOKUP_NORMAL,
3525 						     complain|tf_no_cleanup);
3526 	    }
3527 	  else if (explicit_value_init_p)
3528 	    {
3529 	      /* Something like `new int()'.  NO_CLEANUP is needed so
3530 		 we don't try and build a (possibly ill-formed)
3531 		 destructor.  */
3532 	      tree val = build_value_init (type, complain | tf_no_cleanup);
3533 	      if (val == error_mark_node)
3534 		return error_mark_node;
3535 	      init_expr = build2 (INIT_EXPR, type, init_expr, val);
3536 	    }
3537 	  else
3538 	    {
3539 	      tree ie;
3540 
3541 	      /* We are processing something like `new int (10)', which
3542 		 means allocate an int, and initialize it with 10.  */
3543 
3544 	      ie = build_x_compound_expr_from_vec (*init, "new initializer",
3545 						   complain);
3546 	      init_expr = cp_build_modify_expr (input_location, init_expr,
3547 						INIT_EXPR, ie, complain);
3548 	    }
3549 	  /* If the initializer uses C++14 aggregate NSDMI that refer to the
3550 	     object being initialized, replace them now and don't try to
3551 	     preevaluate.  */
3552 	  bool had_placeholder = false;
3553 	  if (!processing_template_decl
3554 	      && TREE_CODE (init_expr) == INIT_EXPR)
3555 	    TREE_OPERAND (init_expr, 1)
3556 	      = replace_placeholders (TREE_OPERAND (init_expr, 1),
3557 				      TREE_OPERAND (init_expr, 0),
3558 				      &had_placeholder);
3559 	  stable = (!had_placeholder
3560 		    && stabilize_init (init_expr, &init_preeval_expr));
3561 	}
3562 
3563       if (init_expr == error_mark_node)
3564 	return error_mark_node;
3565 
3566       /* If any part of the object initialization terminates by throwing an
3567 	 exception and a suitable deallocation function can be found, the
3568 	 deallocation function is called to free the memory in which the
3569 	 object was being constructed, after which the exception continues
3570 	 to propagate in the context of the new-expression. If no
3571 	 unambiguous matching deallocation function can be found,
3572 	 propagating the exception does not cause the object's memory to be
3573 	 freed.  */
3574       if (flag_exceptions)
3575 	{
3576 	  enum tree_code dcode = array_p ? VEC_DELETE_EXPR : DELETE_EXPR;
3577 	  tree cleanup;
3578 
3579 	  /* The Standard is unclear here, but the right thing to do
3580 	     is to use the same method for finding deallocation
3581 	     functions that we use for finding allocation functions.  */
3582 	  cleanup = (build_op_delete_call
3583 		     (dcode,
3584 		      alloc_node,
3585 		      size,
3586 		      globally_qualified_p,
3587 		      placement_allocation_fn_p ? alloc_call : NULL_TREE,
3588 		      alloc_fn,
3589 		      complain));
3590 
3591 	  if (!cleanup)
3592 	    /* We're done.  */;
3593 	  else if (stable)
3594 	    /* This is much simpler if we were able to preevaluate all of
3595 	       the arguments to the constructor call.  */
3596 	    {
3597 	      /* CLEANUP is compiler-generated, so no diagnostics.  */
3598 	      TREE_NO_WARNING (cleanup) = true;
3599 	      init_expr = build2 (TRY_CATCH_EXPR, void_type_node,
3600 				  init_expr, cleanup);
3601 	      /* Likewise, this try-catch is compiler-generated.  */
3602 	      TREE_NO_WARNING (init_expr) = true;
3603 	    }
3604 	  else
3605 	    /* Ack!  First we allocate the memory.  Then we set our sentry
3606 	       variable to true, and expand a cleanup that deletes the
3607 	       memory if sentry is true.  Then we run the constructor, and
3608 	       finally clear the sentry.
3609 
3610 	       We need to do this because we allocate the space first, so
3611 	       if there are any temporaries with cleanups in the
3612 	       constructor args and we weren't able to preevaluate them, we
3613 	       need this EH region to extend until end of full-expression
3614 	       to preserve nesting.  */
3615 	    {
3616 	      tree end, sentry, begin;
3617 
3618 	      begin = get_target_expr (boolean_true_node);
3619 	      CLEANUP_EH_ONLY (begin) = 1;
3620 
3621 	      sentry = TARGET_EXPR_SLOT (begin);
3622 
3623 	      /* CLEANUP is compiler-generated, so no diagnostics.  */
3624 	      TREE_NO_WARNING (cleanup) = true;
3625 
3626 	      TARGET_EXPR_CLEANUP (begin)
3627 		= build3 (COND_EXPR, void_type_node, sentry,
3628 			  cleanup, void_node);
3629 
3630 	      end = build2 (MODIFY_EXPR, TREE_TYPE (sentry),
3631 			    sentry, boolean_false_node);
3632 
3633 	      init_expr
3634 		= build2 (COMPOUND_EXPR, void_type_node, begin,
3635 			  build2 (COMPOUND_EXPR, void_type_node, init_expr,
3636 				  end));
3637 	      /* Likewise, this is compiler-generated.  */
3638 	      TREE_NO_WARNING (init_expr) = true;
3639 	    }
3640 	}
3641     }
3642   else
3643     init_expr = NULL_TREE;
3644 
3645   /* Now build up the return value in reverse order.  */
3646 
3647   rval = data_addr;
3648 
3649   if (init_expr)
3650     rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), init_expr, rval);
3651   if (cookie_expr)
3652     rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), cookie_expr, rval);
3653 
3654   if (rval == data_addr)
3655     /* If we don't have an initializer or a cookie, strip the TARGET_EXPR
3656        and return the call (which doesn't need to be adjusted).  */
3657     rval = TARGET_EXPR_INITIAL (alloc_expr);
3658   else
3659     {
3660       if (check_new)
3661 	{
3662 	  tree ifexp = cp_build_binary_op (input_location,
3663 					   NE_EXPR, alloc_node,
3664 					   nullptr_node,
3665 					   complain);
3666 	  rval = build_conditional_expr (input_location, ifexp, rval,
3667 					 alloc_node, complain);
3668 	}
3669 
3670       /* Perform the allocation before anything else, so that ALLOC_NODE
3671 	 has been initialized before we start using it.  */
3672       rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), alloc_expr, rval);
3673     }
3674 
3675   if (init_preeval_expr)
3676     rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), init_preeval_expr, rval);
3677 
3678   /* A new-expression is never an lvalue.  */
3679   gcc_assert (!obvalue_p (rval));
3680 
3681   return convert (pointer_type, rval);
3682 }
3683 
3684 /* Generate a representation for a C++ "new" expression.  *PLACEMENT
3685    is a vector of placement-new arguments (or NULL if none).  If NELTS
3686    is NULL, TYPE is the type of the storage to be allocated.  If NELTS
3687    is not NULL, then this is an array-new allocation; TYPE is the type
3688    of the elements in the array and NELTS is the number of elements in
3689    the array.  *INIT, if non-NULL, is the initializer for the new
3690    object, or an empty vector to indicate an initializer of "()".  If
3691    USE_GLOBAL_NEW is true, then the user explicitly wrote "::new"
3692    rather than just "new".  This may change PLACEMENT and INIT.  */
3693 
3694 tree
build_new(vec<tree,va_gc> ** placement,tree type,tree nelts,vec<tree,va_gc> ** init,int use_global_new,tsubst_flags_t complain)3695 build_new (vec<tree, va_gc> **placement, tree type, tree nelts,
3696 	   vec<tree, va_gc> **init, int use_global_new, tsubst_flags_t complain)
3697 {
3698   tree rval;
3699   vec<tree, va_gc> *orig_placement = NULL;
3700   tree orig_nelts = NULL_TREE;
3701   vec<tree, va_gc> *orig_init = NULL;
3702 
3703   if (type == error_mark_node)
3704     return error_mark_node;
3705 
3706   if (nelts == NULL_TREE
3707       /* Don't do auto deduction where it might affect mangling.  */
3708       && (!processing_template_decl || at_function_scope_p ()))
3709     {
3710       tree auto_node = type_uses_auto (type);
3711       if (auto_node)
3712 	{
3713 	  tree d_init = NULL_TREE;
3714 	  const size_t len = vec_safe_length (*init);
3715 	  /* E.g. new auto(x) must have exactly one element, or
3716 	     a {} initializer will have one element.  */
3717 	  if (len == 1)
3718 	    {
3719 	      d_init = (**init)[0];
3720 	      d_init = resolve_nondeduced_context (d_init, complain);
3721 	    }
3722 	  /* For the rest, e.g. new A(1, 2, 3), create a list.  */
3723 	  else if (len > 1)
3724 	    {
3725 	      unsigned int n;
3726 	      tree t;
3727 	      tree *pp = &d_init;
3728 	      FOR_EACH_VEC_ELT (**init, n, t)
3729 		{
3730 		  t = resolve_nondeduced_context (t, complain);
3731 		  *pp = build_tree_list (NULL_TREE, t);
3732 		  pp = &TREE_CHAIN (*pp);
3733 		}
3734 	    }
3735 	  type = do_auto_deduction (type, d_init, auto_node, complain);
3736 	}
3737     }
3738 
3739   if (processing_template_decl)
3740     {
3741       if (dependent_type_p (type)
3742 	  || any_type_dependent_arguments_p (*placement)
3743 	  || (nelts && type_dependent_expression_p (nelts))
3744 	  || (nelts && *init)
3745 	  || any_type_dependent_arguments_p (*init))
3746 	return build_raw_new_expr (*placement, type, nelts, *init,
3747 				   use_global_new);
3748 
3749       orig_placement = make_tree_vector_copy (*placement);
3750       orig_nelts = nelts;
3751       if (*init)
3752 	{
3753 	  orig_init = make_tree_vector_copy (*init);
3754 	  /* Also copy any CONSTRUCTORs in *init, since reshape_init and
3755 	     digest_init clobber them in place.  */
3756 	  for (unsigned i = 0; i < orig_init->length(); ++i)
3757 	    {
3758 	      tree e = (**init)[i];
3759 	      if (TREE_CODE (e) == CONSTRUCTOR)
3760 		(**init)[i] = copy_node (e);
3761 	    }
3762 	}
3763 
3764       make_args_non_dependent (*placement);
3765       if (nelts)
3766 	nelts = build_non_dependent_expr (nelts);
3767       make_args_non_dependent (*init);
3768     }
3769 
3770   if (nelts)
3771     {
3772       if (!build_expr_type_conversion (WANT_INT | WANT_ENUM, nelts, false))
3773         {
3774           if (complain & tf_error)
3775             permerror (input_location, "size in array new must have integral type");
3776           else
3777             return error_mark_node;
3778         }
3779 
3780       /* Try to determine the constant value only for the purposes
3781 	 of the diagnostic below but continue to use the original
3782 	 value and handle const folding later.  */
3783       const_tree cst_nelts = fold_non_dependent_expr (nelts, complain);
3784 
3785       /* The expression in a noptr-new-declarator is erroneous if it's of
3786 	 non-class type and its value before converting to std::size_t is
3787 	 less than zero. ... If the expression is a constant expression,
3788 	 the program is ill-fomed.  */
3789       if (TREE_CODE (cst_nelts) == INTEGER_CST
3790 	  && !valid_array_size_p (input_location, cst_nelts, NULL_TREE,
3791 				  complain & tf_error))
3792 	return error_mark_node;
3793 
3794       nelts = mark_rvalue_use (nelts);
3795       nelts = cp_save_expr (cp_convert (sizetype, nelts, complain));
3796     }
3797 
3798   /* ``A reference cannot be created by the new operator.  A reference
3799      is not an object (8.2.2, 8.4.3), so a pointer to it could not be
3800      returned by new.'' ARM 5.3.3 */
3801   if (TYPE_REF_P (type))
3802     {
3803       if (complain & tf_error)
3804         error ("new cannot be applied to a reference type");
3805       else
3806         return error_mark_node;
3807       type = TREE_TYPE (type);
3808     }
3809 
3810   if (TREE_CODE (type) == FUNCTION_TYPE)
3811     {
3812       if (complain & tf_error)
3813         error ("new cannot be applied to a function type");
3814       return error_mark_node;
3815     }
3816 
3817   /* The type allocated must be complete.  If the new-type-id was
3818      "T[N]" then we are just checking that "T" is complete here, but
3819      that is equivalent, since the value of "N" doesn't matter.  */
3820   if (!complete_type_or_maybe_complain (type, NULL_TREE, complain))
3821     return error_mark_node;
3822 
3823   rval = build_new_1 (placement, type, nelts, init, use_global_new, complain);
3824   if (rval == error_mark_node)
3825     return error_mark_node;
3826 
3827   if (processing_template_decl)
3828     {
3829       tree ret = build_raw_new_expr (orig_placement, type, orig_nelts,
3830 				     orig_init, use_global_new);
3831       release_tree_vector (orig_placement);
3832       release_tree_vector (orig_init);
3833       return ret;
3834     }
3835 
3836   /* Wrap it in a NOP_EXPR so warn_if_unused_value doesn't complain.  */
3837   rval = build1 (NOP_EXPR, TREE_TYPE (rval), rval);
3838   TREE_NO_WARNING (rval) = 1;
3839 
3840   return rval;
3841 }
3842 
3843 static tree
build_vec_delete_1(tree base,tree maxindex,tree type,special_function_kind auto_delete_vec,int use_global_delete,tsubst_flags_t complain)3844 build_vec_delete_1 (tree base, tree maxindex, tree type,
3845 		    special_function_kind auto_delete_vec,
3846 		    int use_global_delete, tsubst_flags_t complain)
3847 {
3848   tree virtual_size;
3849   tree ptype = build_pointer_type (type = complete_type (type));
3850   tree size_exp;
3851 
3852   /* Temporary variables used by the loop.  */
3853   tree tbase, tbase_init;
3854 
3855   /* This is the body of the loop that implements the deletion of a
3856      single element, and moves temp variables to next elements.  */
3857   tree body;
3858 
3859   /* This is the LOOP_EXPR that governs the deletion of the elements.  */
3860   tree loop = 0;
3861 
3862   /* This is the thing that governs what to do after the loop has run.  */
3863   tree deallocate_expr = 0;
3864 
3865   /* This is the BIND_EXPR which holds the outermost iterator of the
3866      loop.  It is convenient to set this variable up and test it before
3867      executing any other code in the loop.
3868      This is also the containing expression returned by this function.  */
3869   tree controller = NULL_TREE;
3870   tree tmp;
3871 
3872   /* We should only have 1-D arrays here.  */
3873   gcc_assert (TREE_CODE (type) != ARRAY_TYPE);
3874 
3875   if (base == error_mark_node || maxindex == error_mark_node)
3876     return error_mark_node;
3877 
3878   if (!COMPLETE_TYPE_P (type))
3879     {
3880       if (complain & tf_warning)
3881 	{
3882 	  auto_diagnostic_group d;
3883 	  if (warning (OPT_Wdelete_incomplete,
3884 			 "possible problem detected in invocation of "
3885 			 "delete [] operator:"))
3886 	    {
3887 	      cxx_incomplete_type_diagnostic (base, type, DK_WARNING);
3888 	      inform (input_location, "neither the destructor nor the "
3889 			"class-specific operator delete [] will be called, "
3890 			"even if they are declared when the class is defined");
3891 	    }
3892 	}
3893       /* This size won't actually be used.  */
3894       size_exp = size_one_node;
3895       goto no_destructor;
3896     }
3897 
3898   size_exp = size_in_bytes (type);
3899 
3900   if (! MAYBE_CLASS_TYPE_P (type))
3901     goto no_destructor;
3902   else if (TYPE_HAS_TRIVIAL_DESTRUCTOR (type))
3903     {
3904       /* Make sure the destructor is callable.  */
3905       if (type_build_dtor_call (type))
3906 	{
3907 	  tmp = build_delete (ptype, base, sfk_complete_destructor,
3908 			      LOOKUP_NORMAL|LOOKUP_DESTRUCTOR, 1,
3909 			      complain);
3910 	  if (tmp == error_mark_node)
3911 	    return error_mark_node;
3912 	}
3913       goto no_destructor;
3914     }
3915 
3916   /* The below is short by the cookie size.  */
3917   virtual_size = size_binop (MULT_EXPR, size_exp,
3918 			     fold_convert (sizetype, maxindex));
3919 
3920   tbase = create_temporary_var (ptype);
3921   tbase_init
3922     = cp_build_modify_expr (input_location, tbase, NOP_EXPR,
3923 			    fold_build_pointer_plus_loc (input_location,
3924 							 fold_convert (ptype,
3925 								       base),
3926 							 virtual_size),
3927 			    complain);
3928   if (tbase_init == error_mark_node)
3929     return error_mark_node;
3930   controller = build3 (BIND_EXPR, void_type_node, tbase,
3931 		       NULL_TREE, NULL_TREE);
3932   TREE_SIDE_EFFECTS (controller) = 1;
3933 
3934   body = build1 (EXIT_EXPR, void_type_node,
3935 		 build2 (EQ_EXPR, boolean_type_node, tbase,
3936 			 fold_convert (ptype, base)));
3937   tmp = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, size_exp);
3938   tmp = fold_build_pointer_plus (tbase, tmp);
3939   tmp = cp_build_modify_expr (input_location, tbase, NOP_EXPR, tmp, complain);
3940   if (tmp == error_mark_node)
3941     return error_mark_node;
3942   body = build_compound_expr (input_location, body, tmp);
3943   tmp = build_delete (ptype, tbase, sfk_complete_destructor,
3944 		      LOOKUP_NORMAL|LOOKUP_DESTRUCTOR, 1,
3945 		      complain);
3946   if (tmp == error_mark_node)
3947     return error_mark_node;
3948   body = build_compound_expr (input_location, body, tmp);
3949 
3950   loop = build1 (LOOP_EXPR, void_type_node, body);
3951   loop = build_compound_expr (input_location, tbase_init, loop);
3952 
3953  no_destructor:
3954   /* Delete the storage if appropriate.  */
3955   if (auto_delete_vec == sfk_deleting_destructor)
3956     {
3957       tree base_tbd;
3958 
3959       /* The below is short by the cookie size.  */
3960       virtual_size = size_binop (MULT_EXPR, size_exp,
3961 				 fold_convert (sizetype, maxindex));
3962 
3963       if (! TYPE_VEC_NEW_USES_COOKIE (type))
3964 	/* no header */
3965 	base_tbd = base;
3966       else
3967 	{
3968 	  tree cookie_size;
3969 
3970 	  cookie_size = targetm.cxx.get_cookie_size (type);
3971 	  base_tbd = cp_build_binary_op (input_location,
3972 					 MINUS_EXPR,
3973 					 cp_convert (string_type_node,
3974 						     base, complain),
3975 					 cookie_size,
3976 					 complain);
3977 	  if (base_tbd == error_mark_node)
3978 	    return error_mark_node;
3979 	  base_tbd = cp_convert (ptype, base_tbd, complain);
3980 	  /* True size with header.  */
3981 	  virtual_size = size_binop (PLUS_EXPR, virtual_size, cookie_size);
3982 	}
3983 
3984       deallocate_expr = build_op_delete_call (VEC_DELETE_EXPR,
3985 					      base_tbd, virtual_size,
3986 					      use_global_delete & 1,
3987 					      /*placement=*/NULL_TREE,
3988 					      /*alloc_fn=*/NULL_TREE,
3989 					      complain);
3990     }
3991 
3992   body = loop;
3993   if (!deallocate_expr)
3994     ;
3995   else if (!body)
3996     body = deallocate_expr;
3997   else
3998     /* The delete operator mist be called, even if a destructor
3999        throws.  */
4000     body = build2 (TRY_FINALLY_EXPR, void_type_node, body, deallocate_expr);
4001 
4002   if (!body)
4003     body = integer_zero_node;
4004 
4005   /* Outermost wrapper: If pointer is null, punt.  */
4006   tree cond = build2_loc (input_location, NE_EXPR, boolean_type_node, base,
4007 			  fold_convert (TREE_TYPE (base), nullptr_node));
4008   /* This is a compiler generated comparison, don't emit
4009      e.g. -Wnonnull-compare warning for it.  */
4010   TREE_NO_WARNING (cond) = 1;
4011   body = build3_loc (input_location, COND_EXPR, void_type_node,
4012 		     cond, body, integer_zero_node);
4013   COND_EXPR_IS_VEC_DELETE (body) = true;
4014   body = build1 (NOP_EXPR, void_type_node, body);
4015 
4016   if (controller)
4017     {
4018       TREE_OPERAND (controller, 1) = body;
4019       body = controller;
4020     }
4021 
4022   if (TREE_CODE (base) == SAVE_EXPR)
4023     /* Pre-evaluate the SAVE_EXPR outside of the BIND_EXPR.  */
4024     body = build2 (COMPOUND_EXPR, void_type_node, base, body);
4025 
4026   return convert_to_void (body, ICV_CAST, complain);
4027 }
4028 
4029 /* Create an unnamed variable of the indicated TYPE.  */
4030 
4031 tree
create_temporary_var(tree type)4032 create_temporary_var (tree type)
4033 {
4034   tree decl;
4035 
4036   decl = build_decl (input_location,
4037 		     VAR_DECL, NULL_TREE, type);
4038   TREE_USED (decl) = 1;
4039   DECL_ARTIFICIAL (decl) = 1;
4040   DECL_IGNORED_P (decl) = 1;
4041   DECL_CONTEXT (decl) = current_function_decl;
4042 
4043   return decl;
4044 }
4045 
4046 /* Create a new temporary variable of the indicated TYPE, initialized
4047    to INIT.
4048 
4049    It is not entered into current_binding_level, because that breaks
4050    things when it comes time to do final cleanups (which take place
4051    "outside" the binding contour of the function).  */
4052 
4053 tree
get_temp_regvar(tree type,tree init)4054 get_temp_regvar (tree type, tree init)
4055 {
4056   tree decl;
4057 
4058   decl = create_temporary_var (type);
4059   add_decl_expr (decl);
4060 
4061   finish_expr_stmt (cp_build_modify_expr (input_location, decl, INIT_EXPR,
4062 					  init, tf_warning_or_error));
4063 
4064   return decl;
4065 }
4066 
4067 /* Subroutine of build_vec_init.  Returns true if assigning to an array of
4068    INNER_ELT_TYPE from INIT is trivial.  */
4069 
4070 static bool
vec_copy_assign_is_trivial(tree inner_elt_type,tree init)4071 vec_copy_assign_is_trivial (tree inner_elt_type, tree init)
4072 {
4073   tree fromtype = inner_elt_type;
4074   if (lvalue_p (init))
4075     fromtype = cp_build_reference_type (fromtype, /*rval*/false);
4076   return is_trivially_xible (MODIFY_EXPR, inner_elt_type, fromtype);
4077 }
4078 
4079 /* Subroutine of build_vec_init: Check that the array has at least N
4080    elements.  Other parameters are local variables in build_vec_init.  */
4081 
4082 void
finish_length_check(tree atype,tree iterator,tree obase,unsigned n)4083 finish_length_check (tree atype, tree iterator, tree obase, unsigned n)
4084 {
4085   tree nelts = build_int_cst (ptrdiff_type_node, n - 1);
4086   if (TREE_CODE (atype) != ARRAY_TYPE)
4087     {
4088       if (flag_exceptions)
4089 	{
4090 	  tree c = fold_build2 (LT_EXPR, boolean_type_node, iterator,
4091 				nelts);
4092 	  c = build3 (COND_EXPR, void_type_node, c,
4093 		      throw_bad_array_new_length (), void_node);
4094 	  finish_expr_stmt (c);
4095 	}
4096       /* Don't check an array new when -fno-exceptions.  */
4097     }
4098   else if (sanitize_flags_p (SANITIZE_BOUNDS)
4099 	   && current_function_decl != NULL_TREE)
4100     {
4101       /* Make sure the last element of the initializer is in bounds. */
4102       finish_expr_stmt
4103 	(ubsan_instrument_bounds
4104 	 (input_location, obase, &nelts, /*ignore_off_by_one*/false));
4105     }
4106 }
4107 
4108 /* `build_vec_init' returns tree structure that performs
4109    initialization of a vector of aggregate types.
4110 
4111    BASE is a reference to the vector, of ARRAY_TYPE, or a pointer
4112      to the first element, of POINTER_TYPE.
4113    MAXINDEX is the maximum index of the array (one less than the
4114      number of elements).  It is only used if BASE is a pointer or
4115      TYPE_DOMAIN (TREE_TYPE (BASE)) == NULL_TREE.
4116 
4117    INIT is the (possibly NULL) initializer.
4118 
4119    If EXPLICIT_VALUE_INIT_P is true, then INIT must be NULL.  All
4120    elements in the array are value-initialized.
4121 
4122    FROM_ARRAY is 0 if we should init everything with INIT
4123    (i.e., every element initialized from INIT).
4124    FROM_ARRAY is 1 if we should index into INIT in parallel
4125    with initialization of DECL.
4126    FROM_ARRAY is 2 if we should index into INIT in parallel,
4127    but use assignment instead of initialization.  */
4128 
4129 tree
build_vec_init(tree base,tree maxindex,tree init,bool explicit_value_init_p,int from_array,tsubst_flags_t complain)4130 build_vec_init (tree base, tree maxindex, tree init,
4131 		bool explicit_value_init_p,
4132 		int from_array, tsubst_flags_t complain)
4133 {
4134   tree rval;
4135   tree base2 = NULL_TREE;
4136   tree itype = NULL_TREE;
4137   tree iterator;
4138   /* The type of BASE.  */
4139   tree atype = TREE_TYPE (base);
4140   /* The type of an element in the array.  */
4141   tree type = TREE_TYPE (atype);
4142   /* The element type reached after removing all outer array
4143      types.  */
4144   tree inner_elt_type;
4145   /* The type of a pointer to an element in the array.  */
4146   tree ptype;
4147   tree stmt_expr;
4148   tree compound_stmt;
4149   int destroy_temps;
4150   tree try_block = NULL_TREE;
4151   HOST_WIDE_INT num_initialized_elts = 0;
4152   bool is_global;
4153   tree obase = base;
4154   bool xvalue = false;
4155   bool errors = false;
4156   location_t loc = (init ? cp_expr_loc_or_loc (init, input_location)
4157 		    : location_of (base));
4158 
4159   if (TREE_CODE (atype) == ARRAY_TYPE && TYPE_DOMAIN (atype))
4160     maxindex = array_type_nelts (atype);
4161 
4162   if (maxindex == NULL_TREE || maxindex == error_mark_node)
4163     return error_mark_node;
4164 
4165   maxindex = maybe_constant_value (maxindex);
4166   if (explicit_value_init_p)
4167     gcc_assert (!init);
4168 
4169   inner_elt_type = strip_array_types (type);
4170 
4171   /* Look through the TARGET_EXPR around a compound literal.  */
4172   if (init && TREE_CODE (init) == TARGET_EXPR
4173       && TREE_CODE (TARGET_EXPR_INITIAL (init)) == CONSTRUCTOR
4174       && from_array != 2)
4175     init = TARGET_EXPR_INITIAL (init);
4176 
4177   bool direct_init = false;
4178   if (from_array && init && BRACE_ENCLOSED_INITIALIZER_P (init)
4179       && CONSTRUCTOR_NELTS (init) == 1)
4180     {
4181       tree elt = CONSTRUCTOR_ELT (init, 0)->value;
4182       if (TREE_CODE (TREE_TYPE (elt)) == ARRAY_TYPE)
4183 	{
4184 	  direct_init = DIRECT_LIST_INIT_P (init);
4185 	  init = elt;
4186 	}
4187     }
4188 
4189   /* If we have a braced-init-list or string constant, make sure that the array
4190      is big enough for all the initializers.  */
4191   bool length_check = (init
4192 		       && (TREE_CODE (init) == STRING_CST
4193 			   || (TREE_CODE (init) == CONSTRUCTOR
4194 			       && CONSTRUCTOR_NELTS (init) > 0))
4195 		       && !TREE_CONSTANT (maxindex));
4196 
4197   if (init
4198       && TREE_CODE (atype) == ARRAY_TYPE
4199       && TREE_CONSTANT (maxindex)
4200       && (from_array == 2
4201 	  ? vec_copy_assign_is_trivial (inner_elt_type, init)
4202 	  : !TYPE_NEEDS_CONSTRUCTING (type))
4203       && ((TREE_CODE (init) == CONSTRUCTOR
4204 	   && (BRACE_ENCLOSED_INITIALIZER_P (init)
4205 	       || (same_type_ignoring_top_level_qualifiers_p
4206 		   (atype, TREE_TYPE (init))))
4207 	   /* Don't do this if the CONSTRUCTOR might contain something
4208 	      that might throw and require us to clean up.  */
4209 	   && (vec_safe_is_empty (CONSTRUCTOR_ELTS (init))
4210 	       || ! TYPE_HAS_NONTRIVIAL_DESTRUCTOR (inner_elt_type)))
4211 	  || from_array))
4212     {
4213       /* Do non-default initialization of trivial arrays resulting from
4214 	 brace-enclosed initializers.  In this case, digest_init and
4215 	 store_constructor will handle the semantics for us.  */
4216 
4217       if (BRACE_ENCLOSED_INITIALIZER_P (init))
4218 	init = digest_init (atype, init, complain);
4219       stmt_expr = build2 (INIT_EXPR, atype, base, init);
4220       return stmt_expr;
4221     }
4222 
4223   maxindex = cp_convert (ptrdiff_type_node, maxindex, complain);
4224   maxindex = fold_simple (maxindex);
4225 
4226   if (TREE_CODE (atype) == ARRAY_TYPE)
4227     {
4228       ptype = build_pointer_type (type);
4229       base = decay_conversion (base, complain);
4230       if (base == error_mark_node)
4231 	return error_mark_node;
4232       base = cp_convert (ptype, base, complain);
4233     }
4234   else
4235     ptype = atype;
4236 
4237   /* The code we are generating looks like:
4238      ({
4239        T* t1 = (T*) base;
4240        T* rval = t1;
4241        ptrdiff_t iterator = maxindex;
4242        try {
4243 	 for (; iterator != -1; --iterator) {
4244 	   ... initialize *t1 ...
4245 	   ++t1;
4246 	 }
4247        } catch (...) {
4248 	 ... destroy elements that were constructed ...
4249        }
4250        rval;
4251      })
4252 
4253      We can omit the try and catch blocks if we know that the
4254      initialization will never throw an exception, or if the array
4255      elements do not have destructors.  We can omit the loop completely if
4256      the elements of the array do not have constructors.
4257 
4258      We actually wrap the entire body of the above in a STMT_EXPR, for
4259      tidiness.
4260 
4261      When copying from array to another, when the array elements have
4262      only trivial copy constructors, we should use __builtin_memcpy
4263      rather than generating a loop.  That way, we could take advantage
4264      of whatever cleverness the back end has for dealing with copies
4265      of blocks of memory.  */
4266 
4267   is_global = begin_init_stmts (&stmt_expr, &compound_stmt);
4268   destroy_temps = stmts_are_full_exprs_p ();
4269   current_stmt_tree ()->stmts_are_full_exprs_p = 0;
4270   rval = get_temp_regvar (ptype, base);
4271   base = get_temp_regvar (ptype, rval);
4272   iterator = get_temp_regvar (ptrdiff_type_node, maxindex);
4273 
4274   /* If initializing one array from another, initialize element by
4275      element.  We rely upon the below calls to do the argument
4276      checking.  Evaluate the initializer before entering the try block.  */
4277   if (from_array && init && TREE_CODE (init) != CONSTRUCTOR)
4278     {
4279       if (lvalue_kind (init) & clk_rvalueref)
4280 	xvalue = true;
4281       base2 = decay_conversion (init, complain);
4282       if (base2 == error_mark_node)
4283 	return error_mark_node;
4284       itype = TREE_TYPE (base2);
4285       base2 = get_temp_regvar (itype, base2);
4286       itype = TREE_TYPE (itype);
4287     }
4288 
4289   /* Protect the entire array initialization so that we can destroy
4290      the partially constructed array if an exception is thrown.
4291      But don't do this if we're assigning.  */
4292   if (flag_exceptions && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
4293       && from_array != 2)
4294     {
4295       try_block = begin_try_block ();
4296     }
4297 
4298   /* Should we try to create a constant initializer?  */
4299   bool try_const = (TREE_CODE (atype) == ARRAY_TYPE
4300 		    && TREE_CONSTANT (maxindex)
4301 		    && (init ? TREE_CODE (init) == CONSTRUCTOR
4302 			: (type_has_constexpr_default_constructor
4303 			   (inner_elt_type)))
4304 		    && (literal_type_p (inner_elt_type)
4305 			|| TYPE_HAS_CONSTEXPR_CTOR (inner_elt_type)));
4306   vec<constructor_elt, va_gc> *const_vec = NULL;
4307   bool saw_non_const = false;
4308   /* If we're initializing a static array, we want to do static
4309      initialization of any elements with constant initializers even if
4310      some are non-constant.  */
4311   bool do_static_init = (DECL_P (obase) && TREE_STATIC (obase));
4312 
4313   bool empty_list = false;
4314   if (init && BRACE_ENCLOSED_INITIALIZER_P (init)
4315       && CONSTRUCTOR_NELTS (init) == 0)
4316     /* Skip over the handling of non-empty init lists.  */
4317     empty_list = true;
4318 
4319   /* Maybe pull out constant value when from_array? */
4320 
4321   else if (init != NULL_TREE && TREE_CODE (init) == CONSTRUCTOR)
4322     {
4323       /* Do non-default initialization of non-trivial arrays resulting from
4324 	 brace-enclosed initializers.  */
4325       unsigned HOST_WIDE_INT idx;
4326       tree field, elt;
4327       /* If the constructor already has the array type, it's been through
4328 	 digest_init, so we shouldn't try to do anything more.  */
4329       bool digested = same_type_p (atype, TREE_TYPE (init));
4330       from_array = 0;
4331 
4332       if (length_check)
4333 	finish_length_check (atype, iterator, obase, CONSTRUCTOR_NELTS (init));
4334 
4335       if (try_const)
4336 	vec_alloc (const_vec, CONSTRUCTOR_NELTS (init));
4337 
4338       FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init), idx, field, elt)
4339 	{
4340 	  tree baseref = build1 (INDIRECT_REF, type, base);
4341 	  tree one_init;
4342 
4343 	  num_initialized_elts++;
4344 
4345 	  current_stmt_tree ()->stmts_are_full_exprs_p = 1;
4346 	  if (digested)
4347 	    one_init = build2 (INIT_EXPR, type, baseref, elt);
4348 	  else if (MAYBE_CLASS_TYPE_P (type) || TREE_CODE (type) == ARRAY_TYPE)
4349 	    one_init = build_aggr_init (baseref, elt, 0, complain);
4350 	  else
4351 	    one_init = cp_build_modify_expr (input_location, baseref,
4352 					     NOP_EXPR, elt, complain);
4353 	  if (one_init == error_mark_node)
4354 	    errors = true;
4355 	  if (try_const)
4356 	    {
4357 	      tree e = maybe_constant_init (one_init);
4358 	      if (reduced_constant_expression_p (e))
4359 		{
4360 		  CONSTRUCTOR_APPEND_ELT (const_vec, field, e);
4361 		  if (do_static_init)
4362 		    one_init = NULL_TREE;
4363 		  else
4364 		    one_init = build2 (INIT_EXPR, type, baseref, e);
4365 		}
4366 	      else
4367 		{
4368 		  if (do_static_init)
4369 		    {
4370 		      tree value = build_zero_init (TREE_TYPE (e), NULL_TREE,
4371 						    true);
4372 		      if (value)
4373 			CONSTRUCTOR_APPEND_ELT (const_vec, field, value);
4374 		    }
4375 		  saw_non_const = true;
4376 		}
4377 	    }
4378 
4379 	  if (one_init)
4380 	    finish_expr_stmt (one_init);
4381 	  current_stmt_tree ()->stmts_are_full_exprs_p = 0;
4382 
4383 	  one_init = cp_build_unary_op (PREINCREMENT_EXPR, base, false,
4384 					complain);
4385 	  if (one_init == error_mark_node)
4386 	    errors = true;
4387 	  else
4388 	    finish_expr_stmt (one_init);
4389 
4390 	  one_init = cp_build_unary_op (PREDECREMENT_EXPR, iterator, false,
4391 					complain);
4392 	  if (one_init == error_mark_node)
4393 	    errors = true;
4394 	  else
4395 	    finish_expr_stmt (one_init);
4396 	}
4397 
4398       /* Any elements without explicit initializers get T{}.  */
4399       empty_list = true;
4400     }
4401   else if (init && TREE_CODE (init) == STRING_CST)
4402     {
4403       /* Check that the array is at least as long as the string.  */
4404       if (length_check)
4405 	finish_length_check (atype, iterator, obase,
4406 			     TREE_STRING_LENGTH (init));
4407       tree length = build_int_cst (ptrdiff_type_node,
4408 				   TREE_STRING_LENGTH (init));
4409 
4410       /* Copy the string to the first part of the array.  */
4411       tree alias_set = build_int_cst (build_pointer_type (type), 0);
4412       tree lhs = build2 (MEM_REF, TREE_TYPE (init), base, alias_set);
4413       tree stmt = build2 (MODIFY_EXPR, void_type_node, lhs, init);
4414       finish_expr_stmt (stmt);
4415 
4416       /* Adjust the counter and pointer.  */
4417       stmt = cp_build_binary_op (loc, MINUS_EXPR, iterator, length, complain);
4418       stmt = build2 (MODIFY_EXPR, void_type_node, iterator, stmt);
4419       finish_expr_stmt (stmt);
4420 
4421       stmt = cp_build_binary_op (loc, PLUS_EXPR, base, length, complain);
4422       stmt = build2 (MODIFY_EXPR, void_type_node, base, stmt);
4423       finish_expr_stmt (stmt);
4424 
4425       /* And set the rest of the array to NUL.  */
4426       from_array = 0;
4427       explicit_value_init_p = true;
4428     }
4429   else if (from_array)
4430     {
4431       if (init)
4432 	/* OK, we set base2 above.  */;
4433       else if (CLASS_TYPE_P (type)
4434 	       && ! TYPE_HAS_DEFAULT_CONSTRUCTOR (type))
4435 	{
4436           if (complain & tf_error)
4437             error ("initializer ends prematurely");
4438 	  errors = true;
4439 	}
4440     }
4441 
4442   /* Now, default-initialize any remaining elements.  We don't need to
4443      do that if a) the type does not need constructing, or b) we've
4444      already initialized all the elements.
4445 
4446      We do need to keep going if we're copying an array.  */
4447 
4448   if (try_const && !init)
4449     /* With a constexpr default constructor, which we checked for when
4450        setting try_const above, default-initialization is equivalent to
4451        value-initialization, and build_value_init gives us something more
4452        friendly to maybe_constant_init.  */
4453     explicit_value_init_p = true;
4454   if (from_array
4455       || ((type_build_ctor_call (type) || init || explicit_value_init_p)
4456 	  && ! (tree_fits_shwi_p (maxindex)
4457 		&& (num_initialized_elts
4458 		    == tree_to_shwi (maxindex) + 1))))
4459     {
4460       /* If the ITERATOR is lesser or equal to -1, then we don't have to loop;
4461 	 we've already initialized all the elements.  */
4462       tree for_stmt;
4463       tree elt_init;
4464       tree to;
4465 
4466       for_stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
4467       finish_init_stmt (for_stmt);
4468       finish_for_cond (build2 (GT_EXPR, boolean_type_node, iterator,
4469 			       build_int_cst (TREE_TYPE (iterator), -1)),
4470 		       for_stmt, false, 0);
4471       elt_init = cp_build_unary_op (PREDECREMENT_EXPR, iterator, false,
4472 				    complain);
4473       if (elt_init == error_mark_node)
4474 	errors = true;
4475       finish_for_expr (elt_init, for_stmt);
4476 
4477       to = build1 (INDIRECT_REF, type, base);
4478 
4479       /* If the initializer is {}, then all elements are initialized from T{}.
4480 	 But for non-classes, that's the same as value-initialization.  */
4481       if (empty_list)
4482 	{
4483 	  if (cxx_dialect >= cxx11 && AGGREGATE_TYPE_P (type))
4484 	    {
4485 	      init = build_constructor (init_list_type_node, NULL);
4486 	    }
4487 	  else
4488 	    {
4489 	      init = NULL_TREE;
4490 	      explicit_value_init_p = true;
4491 	    }
4492 	}
4493 
4494       if (from_array)
4495 	{
4496 	  tree from;
4497 
4498 	  if (base2)
4499 	    {
4500 	      from = build1 (INDIRECT_REF, itype, base2);
4501 	      if (xvalue)
4502 		from = move (from);
4503 	      if (direct_init)
4504 		from = build_tree_list (NULL_TREE, from);
4505 	    }
4506 	  else
4507 	    from = NULL_TREE;
4508 
4509 	  if (TREE_CODE (type) == ARRAY_TYPE)
4510 	    elt_init = build_vec_init (to, NULL_TREE, from, /*val_init*/false,
4511 				       from_array, complain);
4512 	  else if (from_array == 2)
4513 	    elt_init = cp_build_modify_expr (input_location, to, NOP_EXPR,
4514 					     from, complain);
4515 	  else if (type_build_ctor_call (type))
4516 	    elt_init = build_aggr_init (to, from, 0, complain);
4517 	  else if (from)
4518 	    elt_init = cp_build_modify_expr (input_location, to, NOP_EXPR, from,
4519 					     complain);
4520 	  else
4521 	    gcc_unreachable ();
4522 	}
4523       else if (TREE_CODE (type) == ARRAY_TYPE)
4524 	{
4525 	  if (init && !BRACE_ENCLOSED_INITIALIZER_P (init))
4526 	    {
4527 	      if ((complain & tf_error))
4528 		error_at (loc, "array must be initialized "
4529 			  "with a brace-enclosed initializer");
4530 	      elt_init = error_mark_node;
4531 	    }
4532 	  else
4533 	    elt_init = build_vec_init (build1 (INDIRECT_REF, type, base),
4534 				       0, init,
4535 				       explicit_value_init_p,
4536 				       0, complain);
4537 	}
4538       else if (explicit_value_init_p)
4539 	{
4540 	  elt_init = build_value_init (type, complain);
4541 	  if (elt_init != error_mark_node)
4542 	    elt_init = build2 (INIT_EXPR, type, to, elt_init);
4543 	}
4544       else
4545 	{
4546 	  gcc_assert (type_build_ctor_call (type) || init);
4547 	  if (CLASS_TYPE_P (type))
4548 	    elt_init = build_aggr_init (to, init, 0, complain);
4549 	  else
4550 	    {
4551 	      if (TREE_CODE (init) == TREE_LIST)
4552 		init = build_x_compound_expr_from_list (init, ELK_INIT,
4553 							complain);
4554 	      elt_init = (init == error_mark_node
4555 			  ? error_mark_node
4556 			  : build2 (INIT_EXPR, type, to, init));
4557 	    }
4558 	}
4559 
4560       if (elt_init == error_mark_node)
4561 	errors = true;
4562 
4563       if (try_const)
4564 	{
4565 	  /* FIXME refs to earlier elts */
4566 	  tree e = maybe_constant_init (elt_init);
4567 	  if (reduced_constant_expression_p (e))
4568 	    {
4569 	      if (initializer_zerop (e))
4570 		/* Don't fill the CONSTRUCTOR with zeros.  */
4571 		e = NULL_TREE;
4572 	      if (do_static_init)
4573 		elt_init = NULL_TREE;
4574 	    }
4575 	  else
4576 	    {
4577 	      saw_non_const = true;
4578 	      if (do_static_init)
4579 		e = build_zero_init (TREE_TYPE (e), NULL_TREE, true);
4580 	      else
4581 		e = NULL_TREE;
4582 	    }
4583 
4584 	  if (e)
4585 	    {
4586 	      HOST_WIDE_INT last = tree_to_shwi (maxindex);
4587 	      if (num_initialized_elts <= last)
4588 		{
4589 		  tree field = size_int (num_initialized_elts);
4590 		  if (num_initialized_elts != last)
4591 		    field = build2 (RANGE_EXPR, sizetype, field,
4592 				    size_int (last));
4593 		  CONSTRUCTOR_APPEND_ELT (const_vec, field, e);
4594 		}
4595 	    }
4596 	}
4597 
4598       current_stmt_tree ()->stmts_are_full_exprs_p = 1;
4599       if (elt_init && !errors)
4600 	finish_expr_stmt (elt_init);
4601       current_stmt_tree ()->stmts_are_full_exprs_p = 0;
4602 
4603       finish_expr_stmt (cp_build_unary_op (PREINCREMENT_EXPR, base, false,
4604                                            complain));
4605       if (base2)
4606 	finish_expr_stmt (cp_build_unary_op (PREINCREMENT_EXPR, base2, false,
4607                                              complain));
4608 
4609       finish_for_stmt (for_stmt);
4610     }
4611 
4612   /* Make sure to cleanup any partially constructed elements.  */
4613   if (flag_exceptions && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
4614       && from_array != 2)
4615     {
4616       tree e;
4617       tree m = cp_build_binary_op (input_location,
4618 				   MINUS_EXPR, maxindex, iterator,
4619 				   complain);
4620 
4621       /* Flatten multi-dimensional array since build_vec_delete only
4622 	 expects one-dimensional array.  */
4623       if (TREE_CODE (type) == ARRAY_TYPE)
4624 	m = cp_build_binary_op (input_location,
4625 				MULT_EXPR, m,
4626 				/* Avoid mixing signed and unsigned.  */
4627 				convert (TREE_TYPE (m),
4628 					 array_type_nelts_total (type)),
4629 				complain);
4630 
4631       finish_cleanup_try_block (try_block);
4632       e = build_vec_delete_1 (rval, m,
4633 			      inner_elt_type, sfk_complete_destructor,
4634 			      /*use_global_delete=*/0, complain);
4635       if (e == error_mark_node)
4636 	errors = true;
4637       finish_cleanup (e, try_block);
4638     }
4639 
4640   /* The value of the array initialization is the array itself, RVAL
4641      is a pointer to the first element.  */
4642   finish_stmt_expr_expr (rval, stmt_expr);
4643 
4644   stmt_expr = finish_init_stmts (is_global, stmt_expr, compound_stmt);
4645 
4646   current_stmt_tree ()->stmts_are_full_exprs_p = destroy_temps;
4647 
4648   if (errors)
4649     return error_mark_node;
4650 
4651   if (try_const)
4652     {
4653       if (!saw_non_const)
4654 	{
4655 	  tree const_init = build_constructor (atype, const_vec);
4656 	  return build2 (INIT_EXPR, atype, obase, const_init);
4657 	}
4658       else if (do_static_init && !vec_safe_is_empty (const_vec))
4659 	DECL_INITIAL (obase) = build_constructor (atype, const_vec);
4660       else
4661 	vec_free (const_vec);
4662     }
4663 
4664   /* Now make the result have the correct type.  */
4665   if (TREE_CODE (atype) == ARRAY_TYPE)
4666     {
4667       atype = build_pointer_type (atype);
4668       stmt_expr = build1 (NOP_EXPR, atype, stmt_expr);
4669       stmt_expr = cp_build_fold_indirect_ref (stmt_expr);
4670       TREE_NO_WARNING (stmt_expr) = 1;
4671     }
4672 
4673   return stmt_expr;
4674 }
4675 
4676 /* Call the DTOR_KIND destructor for EXP.  FLAGS are as for
4677    build_delete.  */
4678 
4679 static tree
build_dtor_call(tree exp,special_function_kind dtor_kind,int flags,tsubst_flags_t complain)4680 build_dtor_call (tree exp, special_function_kind dtor_kind, int flags,
4681 		 tsubst_flags_t complain)
4682 {
4683   tree name;
4684   switch (dtor_kind)
4685     {
4686     case sfk_complete_destructor:
4687       name = complete_dtor_identifier;
4688       break;
4689 
4690     case sfk_base_destructor:
4691       name = base_dtor_identifier;
4692       break;
4693 
4694     case sfk_deleting_destructor:
4695       name = deleting_dtor_identifier;
4696       break;
4697 
4698     default:
4699       gcc_unreachable ();
4700     }
4701 
4702   return build_special_member_call (exp, name,
4703 				    /*args=*/NULL,
4704 				    /*binfo=*/TREE_TYPE (exp),
4705 				    flags,
4706 				    complain);
4707 }
4708 
4709 /* Generate a call to a destructor. TYPE is the type to cast ADDR to.
4710    ADDR is an expression which yields the store to be destroyed.
4711    AUTO_DELETE is the name of the destructor to call, i.e., either
4712    sfk_complete_destructor, sfk_base_destructor, or
4713    sfk_deleting_destructor.
4714 
4715    FLAGS is the logical disjunction of zero or more LOOKUP_
4716    flags.  See cp-tree.h for more info.  */
4717 
4718 tree
build_delete(tree otype,tree addr,special_function_kind auto_delete,int flags,int use_global_delete,tsubst_flags_t complain)4719 build_delete (tree otype, tree addr, special_function_kind auto_delete,
4720 	      int flags, int use_global_delete, tsubst_flags_t complain)
4721 {
4722   tree expr;
4723 
4724   if (addr == error_mark_node)
4725     return error_mark_node;
4726 
4727   tree type = TYPE_MAIN_VARIANT (otype);
4728 
4729   /* Can happen when CURRENT_EXCEPTION_OBJECT gets its type
4730      set to `error_mark_node' before it gets properly cleaned up.  */
4731   if (type == error_mark_node)
4732     return error_mark_node;
4733 
4734   if (TYPE_PTR_P (type))
4735     type = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4736 
4737   if (TREE_CODE (type) == ARRAY_TYPE)
4738     {
4739       if (TYPE_DOMAIN (type) == NULL_TREE)
4740 	{
4741 	  if (complain & tf_error)
4742 	    error ("unknown array size in delete");
4743 	  return error_mark_node;
4744 	}
4745       return build_vec_delete (addr, array_type_nelts (type),
4746 			       auto_delete, use_global_delete, complain);
4747     }
4748 
4749   bool deleting = (auto_delete == sfk_deleting_destructor);
4750   gcc_assert (deleting == !(flags & LOOKUP_DESTRUCTOR));
4751 
4752   if (TYPE_PTR_P (otype))
4753     {
4754       addr = mark_rvalue_use (addr);
4755 
4756       /* We don't want to warn about delete of void*, only other
4757 	  incomplete types.  Deleting other incomplete types
4758 	  invokes undefined behavior, but it is not ill-formed, so
4759 	  compile to something that would even do The Right Thing
4760 	  (TM) should the type have a trivial dtor and no delete
4761 	  operator.  */
4762       if (!VOID_TYPE_P (type))
4763 	{
4764 	  complete_type (type);
4765 	  if (!COMPLETE_TYPE_P (type))
4766 	    {
4767 	      if (complain & tf_warning)
4768 		{
4769 		  auto_diagnostic_group d;
4770 		  if (warning (OPT_Wdelete_incomplete,
4771 				 "possible problem detected in invocation of "
4772 				 "delete operator:"))
4773 		    {
4774 		      cxx_incomplete_type_diagnostic (addr, type, DK_WARNING);
4775 		      inform (input_location,
4776 				"neither the destructor nor the class-specific "
4777 				"operator delete will be called, even if they "
4778 				"are declared when the class is defined");
4779 		    }
4780 		}
4781 	    }
4782 	  else if (deleting && warn_delnonvdtor
4783 	           && MAYBE_CLASS_TYPE_P (type) && !CLASSTYPE_FINAL (type)
4784 		   && TYPE_POLYMORPHIC_P (type))
4785 	    {
4786 	      tree dtor = CLASSTYPE_DESTRUCTOR (type);
4787 	      if (!dtor || !DECL_VINDEX (dtor))
4788 		{
4789 		  if (CLASSTYPE_PURE_VIRTUALS (type))
4790 		    warning (OPT_Wdelete_non_virtual_dtor,
4791 			     "deleting object of abstract class type %qT"
4792 			     " which has non-virtual destructor"
4793 			     " will cause undefined behavior", type);
4794 		  else
4795 		    warning (OPT_Wdelete_non_virtual_dtor,
4796 			     "deleting object of polymorphic class type %qT"
4797 			     " which has non-virtual destructor"
4798 			     " might cause undefined behavior", type);
4799 		}
4800 	    }
4801 	}
4802 
4803       /* Throw away const and volatile on target type of addr.  */
4804       addr = convert_force (build_pointer_type (type), addr, 0, complain);
4805     }
4806   else
4807     {
4808       /* Don't check PROTECT here; leave that decision to the
4809 	 destructor.  If the destructor is accessible, call it,
4810 	 else report error.  */
4811       addr = cp_build_addr_expr (addr, complain);
4812       if (addr == error_mark_node)
4813 	return error_mark_node;
4814 
4815       addr = convert_force (build_pointer_type (type), addr, 0, complain);
4816     }
4817 
4818   if (deleting)
4819     /* We will use ADDR multiple times so we must save it.  */
4820     addr = save_expr (addr);
4821 
4822   bool virtual_p = false;
4823   if (type_build_dtor_call (type))
4824     {
4825       if (CLASSTYPE_LAZY_DESTRUCTOR (type))
4826 	lazily_declare_fn (sfk_destructor, type);
4827       virtual_p = DECL_VIRTUAL_P (CLASSTYPE_DESTRUCTOR (type));
4828     }
4829 
4830   tree head = NULL_TREE;
4831   tree do_delete = NULL_TREE;
4832   bool destroying_delete = false;
4833 
4834   if (!deleting)
4835     {
4836       /* Leave do_delete null.  */
4837     }
4838   /* For `::delete x', we must not use the deleting destructor
4839      since then we would not be sure to get the global `operator
4840      delete'.  */
4841   else if (use_global_delete)
4842     {
4843       head = get_target_expr (build_headof (addr));
4844       /* Delete the object.  */
4845       do_delete = build_op_delete_call (DELETE_EXPR,
4846 					head,
4847 					cxx_sizeof_nowarn (type),
4848 					/*global_p=*/true,
4849 					/*placement=*/NULL_TREE,
4850 					/*alloc_fn=*/NULL_TREE,
4851 					complain);
4852       /* Otherwise, treat this like a complete object destructor
4853 	 call.  */
4854       auto_delete = sfk_complete_destructor;
4855     }
4856   /* If the destructor is non-virtual, there is no deleting
4857      variant.  Instead, we must explicitly call the appropriate
4858      `operator delete' here.  */
4859   else if (!virtual_p)
4860     {
4861       /* Build the call.  */
4862       do_delete = build_op_delete_call (DELETE_EXPR,
4863 					addr,
4864 					cxx_sizeof_nowarn (type),
4865 					/*global_p=*/false,
4866 					/*placement=*/NULL_TREE,
4867 					/*alloc_fn=*/NULL_TREE,
4868 					complain);
4869       /* Call the complete object destructor.  */
4870       auto_delete = sfk_complete_destructor;
4871       if (do_delete != error_mark_node)
4872 	{
4873 	  tree fn = get_callee_fndecl (do_delete);
4874 	  destroying_delete = destroying_delete_p (fn);
4875 	}
4876     }
4877   else if (TYPE_GETS_REG_DELETE (type))
4878     {
4879       /* Make sure we have access to the member op delete, even though
4880 	 we'll actually be calling it from the destructor.  */
4881       build_op_delete_call (DELETE_EXPR, addr, cxx_sizeof_nowarn (type),
4882 			    /*global_p=*/false,
4883 			    /*placement=*/NULL_TREE,
4884 			    /*alloc_fn=*/NULL_TREE,
4885 			    complain);
4886     }
4887 
4888   if (!destroying_delete && type_build_dtor_call (type))
4889     expr = build_dtor_call (cp_build_fold_indirect_ref (addr),
4890 			    auto_delete, flags, complain);
4891   else
4892     expr = build_trivial_dtor_call (addr);
4893   if (expr == error_mark_node)
4894     return error_mark_node;
4895 
4896   if (!deleting)
4897     return expr;
4898 
4899   if (do_delete && !TREE_SIDE_EFFECTS (expr))
4900     expr = do_delete;
4901   else if (do_delete)
4902     /* The delete operator must be called, regardless of whether
4903        the destructor throws.
4904 
4905        [expr.delete]/7 The deallocation function is called
4906        regardless of whether the destructor for the object or some
4907        element of the array throws an exception.  */
4908     expr = build2 (TRY_FINALLY_EXPR, void_type_node, expr, do_delete);
4909 
4910   /* We need to calculate this before the dtor changes the vptr.  */
4911   if (head)
4912     expr = build2 (COMPOUND_EXPR, void_type_node, head, expr);
4913 
4914   /* Handle deleting a null pointer.  */
4915   warning_sentinel s (warn_address);
4916   tree ifexp = cp_build_binary_op (input_location, NE_EXPR, addr,
4917 				   nullptr_node, complain);
4918   ifexp = cp_fully_fold (ifexp);
4919 
4920   if (ifexp == error_mark_node)
4921     return error_mark_node;
4922   /* This is a compiler generated comparison, don't emit
4923      e.g. -Wnonnull-compare warning for it.  */
4924   else if (TREE_CODE (ifexp) == NE_EXPR)
4925     TREE_NO_WARNING (ifexp) = 1;
4926 
4927   if (!integer_nonzerop (ifexp))
4928     expr = build3 (COND_EXPR, void_type_node, ifexp, expr, void_node);
4929 
4930   return expr;
4931 }
4932 
4933 /* At the beginning of a destructor, push cleanups that will call the
4934    destructors for our base classes and members.
4935 
4936    Called from begin_destructor_body.  */
4937 
4938 void
push_base_cleanups(void)4939 push_base_cleanups (void)
4940 {
4941   tree binfo, base_binfo;
4942   int i;
4943   tree member;
4944   tree expr;
4945   vec<tree, va_gc> *vbases;
4946 
4947   /* Run destructors for all virtual baseclasses.  */
4948   if (!ABSTRACT_CLASS_TYPE_P (current_class_type)
4949       && CLASSTYPE_VBASECLASSES (current_class_type))
4950     {
4951       tree cond = (condition_conversion
4952 		   (build2 (BIT_AND_EXPR, integer_type_node,
4953 			    current_in_charge_parm,
4954 			    integer_two_node)));
4955 
4956       /* The CLASSTYPE_VBASECLASSES vector is in initialization
4957 	 order, which is also the right order for pushing cleanups.  */
4958       for (vbases = CLASSTYPE_VBASECLASSES (current_class_type), i = 0;
4959 	   vec_safe_iterate (vbases, i, &base_binfo); i++)
4960 	{
4961 	  if (type_build_dtor_call (BINFO_TYPE (base_binfo)))
4962 	    {
4963 	      expr = build_special_member_call (current_class_ref,
4964 						base_dtor_identifier,
4965 						NULL,
4966 						base_binfo,
4967 						(LOOKUP_NORMAL
4968 						 | LOOKUP_NONVIRTUAL),
4969 						tf_warning_or_error);
4970 	      if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (BINFO_TYPE (base_binfo)))
4971 		{
4972 		  expr = build3 (COND_EXPR, void_type_node, cond,
4973 				 expr, void_node);
4974 		  finish_decl_cleanup (NULL_TREE, expr);
4975 		}
4976 	    }
4977 	}
4978     }
4979 
4980   /* Take care of the remaining baseclasses.  */
4981   for (binfo = TYPE_BINFO (current_class_type), i = 0;
4982        BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
4983     {
4984       if (BINFO_VIRTUAL_P (base_binfo)
4985 	  || !type_build_dtor_call (BINFO_TYPE (base_binfo)))
4986 	continue;
4987 
4988       expr = build_special_member_call (current_class_ref,
4989 					base_dtor_identifier,
4990 					NULL, base_binfo,
4991 					LOOKUP_NORMAL | LOOKUP_NONVIRTUAL,
4992                                         tf_warning_or_error);
4993       if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (BINFO_TYPE (base_binfo)))
4994 	finish_decl_cleanup (NULL_TREE, expr);
4995     }
4996 
4997   /* Don't automatically destroy union members.  */
4998   if (TREE_CODE (current_class_type) == UNION_TYPE)
4999     return;
5000 
5001   for (member = TYPE_FIELDS (current_class_type); member;
5002        member = DECL_CHAIN (member))
5003     {
5004       tree this_type = TREE_TYPE (member);
5005       if (this_type == error_mark_node
5006 	  || TREE_CODE (member) != FIELD_DECL
5007 	  || DECL_ARTIFICIAL (member))
5008 	continue;
5009       if (ANON_AGGR_TYPE_P (this_type))
5010 	continue;
5011       if (type_build_dtor_call (this_type))
5012 	{
5013 	  tree this_member = (build_class_member_access_expr
5014 			      (current_class_ref, member,
5015 			       /*access_path=*/NULL_TREE,
5016 			       /*preserve_reference=*/false,
5017 			       tf_warning_or_error));
5018 	  expr = build_delete (this_type, this_member,
5019 			       sfk_complete_destructor,
5020 			       LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR|LOOKUP_NORMAL,
5021 			       0, tf_warning_or_error);
5022 	  if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (this_type))
5023 	    finish_decl_cleanup (NULL_TREE, expr);
5024 	}
5025     }
5026 }
5027 
5028 /* Build a C++ vector delete expression.
5029    MAXINDEX is the number of elements to be deleted.
5030    ELT_SIZE is the nominal size of each element in the vector.
5031    BASE is the expression that should yield the store to be deleted.
5032    This function expands (or synthesizes) these calls itself.
5033    AUTO_DELETE_VEC says whether the container (vector) should be deallocated.
5034 
5035    This also calls delete for virtual baseclasses of elements of the vector.
5036 
5037    Update: MAXINDEX is no longer needed.  The size can be extracted from the
5038    start of the vector for pointers, and from the type for arrays.  We still
5039    use MAXINDEX for arrays because it happens to already have one of the
5040    values we'd have to extract.  (We could use MAXINDEX with pointers to
5041    confirm the size, and trap if the numbers differ; not clear that it'd
5042    be worth bothering.)  */
5043 
5044 tree
build_vec_delete(tree base,tree maxindex,special_function_kind auto_delete_vec,int use_global_delete,tsubst_flags_t complain)5045 build_vec_delete (tree base, tree maxindex,
5046 		  special_function_kind auto_delete_vec,
5047 		  int use_global_delete, tsubst_flags_t complain)
5048 {
5049   tree type;
5050   tree rval;
5051   tree base_init = NULL_TREE;
5052 
5053   type = TREE_TYPE (base);
5054 
5055   if (TYPE_PTR_P (type))
5056     {
5057       /* Step back one from start of vector, and read dimension.  */
5058       tree cookie_addr;
5059       tree size_ptr_type = build_pointer_type (sizetype);
5060 
5061       base = mark_rvalue_use (base);
5062       if (TREE_SIDE_EFFECTS (base))
5063 	{
5064 	  base_init = get_target_expr (base);
5065 	  base = TARGET_EXPR_SLOT (base_init);
5066 	}
5067       type = strip_array_types (TREE_TYPE (type));
5068       cookie_addr = fold_build1_loc (input_location, NEGATE_EXPR,
5069 				 sizetype, TYPE_SIZE_UNIT (sizetype));
5070       cookie_addr = fold_build_pointer_plus (fold_convert (size_ptr_type, base),
5071 					     cookie_addr);
5072       maxindex = cp_build_fold_indirect_ref (cookie_addr);
5073     }
5074   else if (TREE_CODE (type) == ARRAY_TYPE)
5075     {
5076       /* Get the total number of things in the array, maxindex is a
5077 	 bad name.  */
5078       maxindex = array_type_nelts_total (type);
5079       type = strip_array_types (type);
5080       base = decay_conversion (base, complain);
5081       if (base == error_mark_node)
5082 	return error_mark_node;
5083       if (TREE_SIDE_EFFECTS (base))
5084 	{
5085 	  base_init = get_target_expr (base);
5086 	  base = TARGET_EXPR_SLOT (base_init);
5087 	}
5088     }
5089   else
5090     {
5091       if (base != error_mark_node && !(complain & tf_error))
5092 	error ("type to vector delete is neither pointer or array type");
5093       return error_mark_node;
5094     }
5095 
5096   rval = build_vec_delete_1 (base, maxindex, type, auto_delete_vec,
5097 			     use_global_delete, complain);
5098   if (base_init && rval != error_mark_node)
5099     rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), base_init, rval);
5100 
5101   return rval;
5102 }
5103 
5104 #include "gt-cp-init.h"
5105