1 /* Handle initialization things in C++.
2    Copyright (C) 1987-2018 Free Software Foundation, Inc.
3    Contributed by Michael Tiemann (tiemann@cygnus.com)
4 
5 This file is part of GCC.
6 
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
10 any later version.
11 
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 GNU General Public License for more details.
16 
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3.  If not see
19 <http://www.gnu.org/licenses/>.  */
20 
21 /* 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,
249 				 MINUS_EXPR, TREE_TYPE (nelts),
250 				 nelts, integer_one_node);
251       else
252 	max_index = array_type_nelts (type);
253 
254       /* If we have an error_mark here, we should just return error mark
255 	 as we don't know the size of the array yet.  */
256       if (max_index == error_mark_node)
257 	return error_mark_node;
258       gcc_assert (TREE_CODE (max_index) == INTEGER_CST);
259 
260       /* A zero-sized array, which is accepted as an extension, will
261 	 have an upper bound of -1.  */
262       if (!tree_int_cst_equal (max_index, integer_minus_one_node))
263 	{
264 	  constructor_elt ce;
265 
266 	  /* If this is a one element array, we just use a regular init.  */
267 	  if (tree_int_cst_equal (size_zero_node, max_index))
268 	    ce.index = size_zero_node;
269 	  else
270 	    ce.index = build2 (RANGE_EXPR, sizetype, size_zero_node,
271 				max_index);
272 
273 	  ce.value = build_zero_init_1 (TREE_TYPE (type),
274 					 /*nelts=*/NULL_TREE,
275 					 static_storage_p, NULL_TREE);
276 	  if (ce.value)
277 	    {
278 	      vec_alloc (v, 1);
279 	      v->quick_push (ce);
280 	    }
281 	}
282 
283       /* Build a constructor to contain the initializations.  */
284       init = build_constructor (type, v);
285     }
286   else if (VECTOR_TYPE_P (type))
287     init = build_zero_cst (type);
288   else
289     {
290       gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
291       init = build_zero_cst (type);
292     }
293 
294   /* In all cases, the initializer is a constant.  */
295   if (init)
296     TREE_CONSTANT (init) = 1;
297 
298   return init;
299 }
300 
301 /* Return an expression for the zero-initialization of an object with
302    type T.  This expression will either be a constant (in the case
303    that T is a scalar), or a CONSTRUCTOR (in the case that T is an
304    aggregate), or NULL (in the case that T does not require
305    initialization).  In either case, the value can be used as
306    DECL_INITIAL for a decl of the indicated TYPE; it is a valid static
307    initializer. If NELTS is non-NULL, and TYPE is an ARRAY_TYPE, NELTS
308    is the number of elements in the array.  If STATIC_STORAGE_P is
309    TRUE, initializers are only generated for entities for which
310    zero-initialization does not simply mean filling the storage with
311    zero bytes.  */
312 
313 tree
build_zero_init(tree type,tree nelts,bool static_storage_p)314 build_zero_init (tree type, tree nelts, bool static_storage_p)
315 {
316   return build_zero_init_1 (type, nelts, static_storage_p, NULL_TREE);
317 }
318 
319 /* Return a suitable initializer for value-initializing an object of type
320    TYPE, as described in [dcl.init].  */
321 
322 tree
build_value_init(tree type,tsubst_flags_t complain)323 build_value_init (tree type, tsubst_flags_t complain)
324 {
325   /* [dcl.init]
326 
327      To value-initialize an object of type T means:
328 
329      - if T is a class type (clause 9) with either no default constructor
330        (12.1) or a default constructor that is user-provided or deleted,
331        then the object is default-initialized;
332 
333      - if T is a (possibly cv-qualified) class type without a user-provided
334        or deleted default constructor, then the object is zero-initialized
335        and the semantic constraints for default-initialization are checked,
336        and if T has a non-trivial default constructor, the object is
337        default-initialized;
338 
339      - if T is an array type, then each element is value-initialized;
340 
341      - otherwise, the object is zero-initialized.
342 
343      A program that calls for default-initialization or
344      value-initialization of an entity of reference type is ill-formed.  */
345 
346   /* The AGGR_INIT_EXPR tweaking below breaks in templates.  */
347   gcc_assert (!processing_template_decl
348 	      || (SCALAR_TYPE_P (type) || TREE_CODE (type) == ARRAY_TYPE));
349 
350   if (CLASS_TYPE_P (type)
351       && type_build_ctor_call (type))
352     {
353       tree ctor =
354 	 build_special_member_call (NULL_TREE, complete_ctor_identifier,
355 				    NULL, type, LOOKUP_NORMAL,
356 				    complain);
357       if (ctor == error_mark_node)
358 	return ctor;
359       tree fn = NULL_TREE;
360       if (TREE_CODE (ctor) == CALL_EXPR)
361 	fn = get_callee_fndecl (ctor);
362       ctor = build_aggr_init_expr (type, ctor);
363       if (fn && user_provided_p (fn))
364 	return ctor;
365       else if (TYPE_HAS_COMPLEX_DFLT (type))
366 	{
367 	  /* This is a class that needs constructing, but doesn't have
368 	     a user-provided constructor.  So we need to zero-initialize
369 	     the object and then call the implicitly defined ctor.
370 	     This will be handled in simplify_aggr_init_expr.  */
371 	  AGGR_INIT_ZERO_FIRST (ctor) = 1;
372 	  return ctor;
373 	}
374     }
375 
376   /* Discard any access checking during subobject initialization;
377      the checks are implied by the call to the ctor which we have
378      verified is OK (cpp0x/defaulted46.C).  */
379   push_deferring_access_checks (dk_deferred);
380   tree r = build_value_init_noctor (type, complain);
381   pop_deferring_access_checks ();
382   return r;
383 }
384 
385 /* Like build_value_init, but don't call the constructor for TYPE.  Used
386    for base initializers.  */
387 
388 tree
build_value_init_noctor(tree type,tsubst_flags_t complain)389 build_value_init_noctor (tree type, tsubst_flags_t complain)
390 {
391   if (!COMPLETE_TYPE_P (type))
392     {
393       if (complain & tf_error)
394 	error ("value-initialization of incomplete type %qT", type);
395       return error_mark_node;
396     }
397   /* FIXME the class and array cases should just use digest_init once it is
398      SFINAE-enabled.  */
399   if (CLASS_TYPE_P (type))
400     {
401       gcc_assert (!TYPE_HAS_COMPLEX_DFLT (type)
402 		  || errorcount != 0);
403 
404       if (TREE_CODE (type) != UNION_TYPE)
405 	{
406 	  tree field;
407 	  vec<constructor_elt, va_gc> *v = NULL;
408 
409 	  /* Iterate over the fields, building initializations.  */
410 	  for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
411 	    {
412 	      tree ftype, value;
413 
414 	      if (TREE_CODE (field) != FIELD_DECL)
415 		continue;
416 
417 	      ftype = TREE_TYPE (field);
418 
419 	      if (ftype == error_mark_node)
420 		continue;
421 
422 	      /* Ignore flexible array members for value initialization.  */
423 	      if (TREE_CODE (ftype) == ARRAY_TYPE
424 		  && !COMPLETE_TYPE_P (ftype)
425 		  && !TYPE_DOMAIN (ftype)
426 		  && COMPLETE_TYPE_P (TREE_TYPE (ftype))
427 		  && (next_initializable_field (DECL_CHAIN (field))
428 		      == NULL_TREE))
429 		continue;
430 
431 	      /* We could skip vfields and fields of types with
432 		 user-defined constructors, but I think that won't improve
433 		 performance at all; it should be simpler in general just
434 		 to zero out the entire object than try to only zero the
435 		 bits that actually need it.  */
436 
437 	      /* Note that for class types there will be FIELD_DECLs
438 		 corresponding to base classes as well.  Thus, iterating
439 		 over TYPE_FIELDs will result in correct initialization of
440 		 all of the subobjects.  */
441 	      value = build_value_init (ftype, complain);
442 	      value = maybe_constant_init (value);
443 
444 	      if (value == error_mark_node)
445 		return error_mark_node;
446 
447 	      CONSTRUCTOR_APPEND_ELT(v, field, value);
448 
449 	      /* We shouldn't have gotten here for anything that would need
450 		 non-trivial initialization, and gimplify_init_ctor_preeval
451 		 would need to be fixed to allow it.  */
452 	      gcc_assert (TREE_CODE (value) != TARGET_EXPR
453 			  && TREE_CODE (value) != AGGR_INIT_EXPR);
454 	    }
455 
456 	  /* Build a constructor to contain the zero- initializations.  */
457 	  return build_constructor (type, v);
458 	}
459     }
460   else if (TREE_CODE (type) == ARRAY_TYPE)
461     {
462       vec<constructor_elt, va_gc> *v = NULL;
463 
464       /* Iterate over the array elements, building initializations.  */
465       tree max_index = array_type_nelts (type);
466 
467       /* If we have an error_mark here, we should just return error mark
468 	 as we don't know the size of the array yet.  */
469       if (max_index == error_mark_node)
470 	{
471 	  if (complain & tf_error)
472 	    error ("cannot value-initialize array of unknown bound %qT",
473 		   type);
474 	  return error_mark_node;
475 	}
476       gcc_assert (TREE_CODE (max_index) == INTEGER_CST);
477 
478       /* A zero-sized array, which is accepted as an extension, will
479 	 have an upper bound of -1.  */
480       if (!tree_int_cst_equal (max_index, integer_minus_one_node))
481 	{
482 	  constructor_elt ce;
483 
484 	  /* If this is a one element array, we just use a regular init.  */
485 	  if (tree_int_cst_equal (size_zero_node, max_index))
486 	    ce.index = size_zero_node;
487 	  else
488 	    ce.index = build2 (RANGE_EXPR, sizetype, size_zero_node, max_index);
489 
490 	  ce.value = build_value_init (TREE_TYPE (type), complain);
491 	  ce.value = maybe_constant_init (ce.value);
492 	  if (ce.value == error_mark_node)
493 	    return error_mark_node;
494 
495 	  vec_alloc (v, 1);
496 	  v->quick_push (ce);
497 
498 	  /* We shouldn't have gotten here for anything that would need
499 	     non-trivial initialization, and gimplify_init_ctor_preeval
500 	     would need to be fixed to allow it.  */
501 	  gcc_assert (TREE_CODE (ce.value) != TARGET_EXPR
502 		      && TREE_CODE (ce.value) != AGGR_INIT_EXPR);
503 	}
504 
505       /* Build a constructor to contain the initializations.  */
506       return build_constructor (type, v);
507     }
508   else if (TREE_CODE (type) == FUNCTION_TYPE)
509     {
510       if (complain & tf_error)
511 	error ("value-initialization of function type %qT", type);
512       return error_mark_node;
513     }
514   else if (TREE_CODE (type) == REFERENCE_TYPE)
515     {
516       if (complain & tf_error)
517 	error ("value-initialization of reference type %qT", type);
518       return error_mark_node;
519     }
520 
521   return build_zero_init (type, NULL_TREE, /*static_storage_p=*/false);
522 }
523 
524 /* Initialize current class with INIT, a TREE_LIST of
525    arguments for a target constructor. If TREE_LIST is void_type_node,
526    an empty initializer list was given.  */
527 
528 static void
perform_target_ctor(tree init)529 perform_target_ctor (tree init)
530 {
531   tree decl = current_class_ref;
532   tree type = current_class_type;
533 
534   finish_expr_stmt (build_aggr_init (decl, init,
535 				     LOOKUP_NORMAL|LOOKUP_DELEGATING_CONS,
536 				     tf_warning_or_error));
537   if (type_build_dtor_call (type))
538     {
539       tree expr = build_delete (type, decl, sfk_complete_destructor,
540 				LOOKUP_NORMAL
541 				|LOOKUP_NONVIRTUAL
542 				|LOOKUP_DESTRUCTOR,
543 				0, tf_warning_or_error);
544       if (expr != error_mark_node
545 	  && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
546 	finish_eh_cleanup (expr);
547     }
548 }
549 
550 /* Return the non-static data initializer for FIELD_DECL MEMBER.  */
551 
552 static GTY((cache)) tree_cache_map *nsdmi_inst;
553 
554 tree
get_nsdmi(tree member,bool in_ctor,tsubst_flags_t complain)555 get_nsdmi (tree member, bool in_ctor, tsubst_flags_t complain)
556 {
557   tree init;
558   tree save_ccp = current_class_ptr;
559   tree save_ccr = current_class_ref;
560 
561   if (DECL_LANG_SPECIFIC (member) && DECL_TEMPLATE_INFO (member))
562     {
563       init = DECL_INITIAL (DECL_TI_TEMPLATE (member));
564       location_t expr_loc
565 	= EXPR_LOC_OR_LOC (init, DECL_SOURCE_LOCATION (member));
566       tree *slot;
567       if (TREE_CODE (init) == DEFAULT_ARG)
568 	/* Unparsed.  */;
569       else if (nsdmi_inst && (slot = nsdmi_inst->get (member)))
570 	init = *slot;
571       /* Check recursive instantiation.  */
572       else if (DECL_INSTANTIATING_NSDMI_P (member))
573 	{
574 	  if (complain & tf_error)
575 	    error_at (expr_loc, "recursive instantiation of default member "
576 		      "initializer for %qD", member);
577 	  init = error_mark_node;
578 	}
579       else
580 	{
581 	  int un = cp_unevaluated_operand;
582 	  cp_unevaluated_operand = 0;
583 
584 	  location_t sloc = input_location;
585 	  input_location = expr_loc;
586 
587 	  DECL_INSTANTIATING_NSDMI_P (member) = 1;
588 
589 	  bool pushed = false;
590 	  if (!currently_open_class (DECL_CONTEXT (member)))
591 	    {
592 	      push_to_top_level ();
593 	      push_nested_class (DECL_CONTEXT (member));
594 	      pushed = true;
595 	    }
596 
597 	  gcc_checking_assert (!processing_template_decl);
598 
599 	  inject_this_parameter (DECL_CONTEXT (member), 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 	  cp_unevaluated_operand = un;
629 	}
630     }
631   else
632     init = DECL_INITIAL (member);
633 
634   if (init && TREE_CODE (init) == DEFAULT_ARG)
635     {
636       if (complain & tf_error)
637 	{
638 	  error ("default member initializer for %qD required before the end "
639 		 "of its enclosing class", member);
640 	  inform (location_of (init), "defined here");
641 	  DECL_INITIAL (member) = error_mark_node;
642 	}
643       init = error_mark_node;
644     }
645 
646   if (in_ctor)
647     {
648       current_class_ptr = save_ccp;
649       current_class_ref = save_ccr;
650     }
651   else
652     {
653       /* Use a PLACEHOLDER_EXPR when we don't have a 'this' parameter to
654 	 refer to; constexpr evaluation knows what to do with it.  */
655       current_class_ref = build0 (PLACEHOLDER_EXPR, DECL_CONTEXT (member));
656       current_class_ptr = build_address (current_class_ref);
657     }
658 
659   /* Strip redundant TARGET_EXPR so we don't need to remap it, and
660      so the aggregate init code below will see a CONSTRUCTOR.  */
661   bool simple_target = (init && SIMPLE_TARGET_EXPR_P (init));
662   if (simple_target)
663     init = TARGET_EXPR_INITIAL (init);
664   init = break_out_target_exprs (init, /*loc*/true);
665   if (simple_target && TREE_CODE (init) != CONSTRUCTOR)
666     /* Now put it back so C++17 copy elision works.  */
667     init = get_target_expr (init);
668 
669   current_class_ptr = save_ccp;
670   current_class_ref = save_ccr;
671   return init;
672 }
673 
674 /* Diagnose the flexible array MEMBER if its INITializer is non-null
675    and return true if so.  Otherwise return false.  */
676 
677 bool
maybe_reject_flexarray_init(tree member,tree init)678 maybe_reject_flexarray_init (tree member, tree init)
679 {
680   tree type = TREE_TYPE (member);
681 
682   if (!init
683       || TREE_CODE (type) != ARRAY_TYPE
684       || TYPE_DOMAIN (type))
685     return false;
686 
687   /* Point at the flexible array member declaration if it's initialized
688      in-class, and at the ctor if it's initialized in a ctor member
689      initializer list.  */
690   location_t loc;
691   if (DECL_INITIAL (member) == init
692       || !current_function_decl
693       || DECL_DEFAULTED_FN (current_function_decl))
694     loc = DECL_SOURCE_LOCATION (member);
695   else
696     loc = DECL_SOURCE_LOCATION (current_function_decl);
697 
698   error_at (loc, "initializer for flexible array member %q#D", member);
699   return true;
700 }
701 
702 /* Initialize MEMBER, a FIELD_DECL, with INIT, a TREE_LIST of
703    arguments.  If TREE_LIST is void_type_node, an empty initializer
704    list was given; if NULL_TREE no initializer was given.  */
705 
706 static void
perform_member_init(tree member,tree init)707 perform_member_init (tree member, tree init)
708 {
709   tree decl;
710   tree type = TREE_TYPE (member);
711 
712   /* Use the non-static data member initializer if there was no
713      mem-initializer for this field.  */
714   if (init == NULL_TREE)
715     init = get_nsdmi (member, /*ctor*/true, tf_warning_or_error);
716 
717   if (init == error_mark_node)
718     return;
719 
720   /* Effective C++ rule 12 requires that all data members be
721      initialized.  */
722   if (warn_ecpp && init == NULL_TREE && TREE_CODE (type) != ARRAY_TYPE)
723     warning_at (DECL_SOURCE_LOCATION (current_function_decl), OPT_Weffc__,
724 		"%qD should be initialized in the member initialization list",
725 		member);
726 
727   /* Get an lvalue for the data member.  */
728   decl = build_class_member_access_expr (current_class_ref, member,
729 					 /*access_path=*/NULL_TREE,
730 					 /*preserve_reference=*/true,
731 					 tf_warning_or_error);
732   if (decl == error_mark_node)
733     return;
734 
735   if (warn_init_self && init && TREE_CODE (init) == TREE_LIST
736       && TREE_CHAIN (init) == NULL_TREE)
737     {
738       tree val = TREE_VALUE (init);
739       /* Handle references.  */
740       if (REFERENCE_REF_P (val))
741 	val = TREE_OPERAND (val, 0);
742       if (TREE_CODE (val) == COMPONENT_REF && TREE_OPERAND (val, 1) == member
743 	  && TREE_OPERAND (val, 0) == current_class_ref)
744 	warning_at (DECL_SOURCE_LOCATION (current_function_decl),
745 		    OPT_Winit_self, "%qD is initialized with itself",
746 		    member);
747     }
748 
749   if (init == void_type_node)
750     {
751       /* mem() means value-initialization.  */
752       if (TREE_CODE (type) == ARRAY_TYPE)
753 	{
754 	  init = build_vec_init_expr (type, init, tf_warning_or_error);
755 	  init = build2 (INIT_EXPR, type, decl, init);
756 	  finish_expr_stmt (init);
757 	}
758       else
759 	{
760 	  tree value = build_value_init (type, tf_warning_or_error);
761 	  if (value == error_mark_node)
762 	    return;
763 	  init = build2 (INIT_EXPR, type, decl, value);
764 	  finish_expr_stmt (init);
765 	}
766     }
767   /* Deal with this here, as we will get confused if we try to call the
768      assignment op for an anonymous union.  This can happen in a
769      synthesized copy constructor.  */
770   else if (ANON_AGGR_TYPE_P (type))
771     {
772       if (init)
773 	{
774 	  init = build2 (INIT_EXPR, type, decl, TREE_VALUE (init));
775 	  finish_expr_stmt (init);
776 	}
777     }
778   else if (init
779 	   && (TREE_CODE (type) == REFERENCE_TYPE
780 	       /* Pre-digested NSDMI.  */
781 	       || (((TREE_CODE (init) == CONSTRUCTOR
782 		     && TREE_TYPE (init) == type)
783 		    /* { } mem-initializer.  */
784 		    || (TREE_CODE (init) == TREE_LIST
785 			&& DIRECT_LIST_INIT_P (TREE_VALUE (init))))
786 		   && (CP_AGGREGATE_TYPE_P (type)
787 		       || is_std_init_list (type)))))
788     {
789       /* With references and list-initialization, we need to deal with
790 	 extending temporary lifetimes.  12.2p5: "A temporary bound to a
791 	 reference member in a constructor’s ctor-initializer (12.6.2)
792 	 persists until the constructor exits."  */
793       unsigned i; tree t;
794       vec<tree, va_gc> *cleanups = make_tree_vector ();
795       if (TREE_CODE (init) == TREE_LIST)
796 	init = build_x_compound_expr_from_list (init, ELK_MEM_INIT,
797 						tf_warning_or_error);
798       if (TREE_TYPE (init) != type)
799 	{
800 	  if (BRACE_ENCLOSED_INITIALIZER_P (init)
801 	      && CP_AGGREGATE_TYPE_P (type))
802 	    init = reshape_init (type, init, tf_warning_or_error);
803 	  init = digest_init (type, init, tf_warning_or_error);
804 	}
805       if (init == error_mark_node)
806 	return;
807       /* A FIELD_DECL doesn't really have a suitable lifetime, but
808 	 make_temporary_var_for_ref_to_temp will treat it as automatic and
809 	 set_up_extended_ref_temp wants to use the decl in a warning.  */
810       init = extend_ref_init_temps (member, init, &cleanups);
811       if (TREE_CODE (type) == ARRAY_TYPE
812 	  && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (type)))
813 	init = build_vec_init_expr (type, init, tf_warning_or_error);
814       init = build2 (INIT_EXPR, type, decl, init);
815       finish_expr_stmt (init);
816       FOR_EACH_VEC_ELT (*cleanups, i, t)
817 	push_cleanup (decl, t, false);
818       release_tree_vector (cleanups);
819     }
820   else if (type_build_ctor_call (type)
821 	   || (init && CLASS_TYPE_P (strip_array_types (type))))
822     {
823       if (TREE_CODE (type) == ARRAY_TYPE)
824 	{
825 	  if (init)
826 	    {
827 	      /* Check to make sure the member initializer is valid and
828 		 something like a CONSTRUCTOR in: T a[] = { 1, 2 } and
829 		 if it isn't, return early to avoid triggering another
830 		 error below.  */
831 	      if (maybe_reject_flexarray_init (member, init))
832 		return;
833 
834 	      if (TREE_CODE (init) != TREE_LIST || TREE_CHAIN (init))
835 		init = error_mark_node;
836 	      else
837 		init = TREE_VALUE (init);
838 
839 	      if (BRACE_ENCLOSED_INITIALIZER_P (init))
840 		init = digest_init (type, init, tf_warning_or_error);
841 	    }
842 	  if (init == NULL_TREE
843 	      || same_type_ignoring_top_level_qualifiers_p (type,
844 							    TREE_TYPE (init)))
845 	    {
846 	      if (TYPE_DOMAIN (type) && TYPE_MAX_VALUE (TYPE_DOMAIN (type)))
847 		{
848 		  /* Initialize the array only if it's not a flexible
849 		     array member (i.e., if it has an upper bound).  */
850 		  init = build_vec_init_expr (type, init, tf_warning_or_error);
851 		  init = build2 (INIT_EXPR, type, decl, init);
852 		  finish_expr_stmt (init);
853 		}
854 	    }
855 	  else
856 	    error ("invalid initializer for array member %q#D", member);
857 	}
858       else
859 	{
860 	  int flags = LOOKUP_NORMAL;
861 	  if (DECL_DEFAULTED_FN (current_function_decl))
862 	    flags |= LOOKUP_DEFAULTED;
863 	  if (CP_TYPE_CONST_P (type)
864 	      && init == NULL_TREE
865 	      && default_init_uninitialized_part (type))
866 	    {
867 	      /* TYPE_NEEDS_CONSTRUCTING can be set just because we have a
868 		 vtable; still give this diagnostic.  */
869 	      if (permerror (DECL_SOURCE_LOCATION (current_function_decl),
870 			     "uninitialized const member in %q#T", type))
871 		inform (DECL_SOURCE_LOCATION (member),
872 			"%q#D should be initialized", member );
873 	    }
874 	  finish_expr_stmt (build_aggr_init (decl, init, flags,
875 					     tf_warning_or_error));
876 	}
877     }
878   else
879     {
880       if (init == NULL_TREE)
881 	{
882 	  tree core_type;
883 	  /* member traversal: note it leaves init NULL */
884 	  if (TREE_CODE (type) == REFERENCE_TYPE)
885 	    {
886 	      if (permerror (DECL_SOURCE_LOCATION (current_function_decl),
887 			     "uninitialized reference member in %q#T", type))
888 		inform (DECL_SOURCE_LOCATION (member),
889 			"%q#D should be initialized", member);
890 	    }
891 	  else if (CP_TYPE_CONST_P (type))
892 	    {
893 	      if (permerror (DECL_SOURCE_LOCATION (current_function_decl),
894 			     "uninitialized const member in %q#T", type))
895 		  inform (DECL_SOURCE_LOCATION (member),
896 			  "%q#D should be initialized", member );
897 	    }
898 
899 	  core_type = strip_array_types (type);
900 
901 	  if (CLASS_TYPE_P (core_type)
902 	      && (CLASSTYPE_READONLY_FIELDS_NEED_INIT (core_type)
903 		  || CLASSTYPE_REF_FIELDS_NEED_INIT (core_type)))
904 	    diagnose_uninitialized_cst_or_ref_member (core_type,
905 						      /*using_new=*/false,
906 						      /*complain=*/true);
907 	}
908       else if (TREE_CODE (init) == TREE_LIST)
909 	/* There was an explicit member initialization.  Do some work
910 	   in that case.  */
911 	init = build_x_compound_expr_from_list (init, ELK_MEM_INIT,
912 						tf_warning_or_error);
913 
914       /* Reject a member initializer for a flexible array member.  */
915       if (init && !maybe_reject_flexarray_init (member, init))
916 	finish_expr_stmt (cp_build_modify_expr (input_location, decl,
917 						INIT_EXPR, init,
918 						tf_warning_or_error));
919     }
920 
921   if (type_build_dtor_call (type))
922     {
923       tree expr;
924 
925       expr = build_class_member_access_expr (current_class_ref, member,
926 					     /*access_path=*/NULL_TREE,
927 					     /*preserve_reference=*/false,
928 					     tf_warning_or_error);
929       expr = build_delete (type, expr, sfk_complete_destructor,
930 			   LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR, 0,
931 			   tf_warning_or_error);
932 
933       if (expr != error_mark_node
934 	  && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
935 	finish_eh_cleanup (expr);
936     }
937 }
938 
939 /* Returns a TREE_LIST containing (as the TREE_PURPOSE of each node) all
940    the FIELD_DECLs on the TYPE_FIELDS list for T, in reverse order.  */
941 
942 static tree
build_field_list(tree t,tree list,int * uses_unions_or_anon_p)943 build_field_list (tree t, tree list, int *uses_unions_or_anon_p)
944 {
945   tree fields;
946 
947   /* Note whether or not T is a union.  */
948   if (TREE_CODE (t) == UNION_TYPE)
949     *uses_unions_or_anon_p = 1;
950 
951   for (fields = TYPE_FIELDS (t); fields; fields = DECL_CHAIN (fields))
952     {
953       tree fieldtype;
954 
955       /* Skip CONST_DECLs for enumeration constants and so forth.  */
956       if (TREE_CODE (fields) != FIELD_DECL || DECL_ARTIFICIAL (fields))
957 	continue;
958 
959       fieldtype = TREE_TYPE (fields);
960 
961       /* For an anonymous struct or union, we must recursively
962 	 consider the fields of the anonymous type.  They can be
963 	 directly initialized from the constructor.  */
964       if (ANON_AGGR_TYPE_P (fieldtype))
965 	{
966 	  /* Add this field itself.  Synthesized copy constructors
967 	     initialize the entire aggregate.  */
968 	  list = tree_cons (fields, NULL_TREE, list);
969 	  /* And now add the fields in the anonymous aggregate.  */
970 	  list = build_field_list (fieldtype, list, uses_unions_or_anon_p);
971 	  *uses_unions_or_anon_p = 1;
972 	}
973       /* Add this field.  */
974       else if (DECL_NAME (fields))
975 	list = tree_cons (fields, NULL_TREE, list);
976     }
977 
978   return list;
979 }
980 
981 /* Return the innermost aggregate scope for FIELD, whether that is
982    the enclosing class or an anonymous aggregate within it.  */
983 
984 static tree
innermost_aggr_scope(tree field)985 innermost_aggr_scope (tree field)
986 {
987   if (ANON_AGGR_TYPE_P (TREE_TYPE (field)))
988     return TREE_TYPE (field);
989   else
990     return DECL_CONTEXT (field);
991 }
992 
993 /* The MEM_INITS are a TREE_LIST.  The TREE_PURPOSE of each list gives
994    a FIELD_DECL or BINFO in T that needs initialization.  The
995    TREE_VALUE gives the initializer, or list of initializer arguments.
996 
997    Return a TREE_LIST containing all of the initializations required
998    for T, in the order in which they should be performed.  The output
999    list has the same format as the input.  */
1000 
1001 static tree
sort_mem_initializers(tree t,tree mem_inits)1002 sort_mem_initializers (tree t, tree mem_inits)
1003 {
1004   tree init;
1005   tree base, binfo, base_binfo;
1006   tree sorted_inits;
1007   tree next_subobject;
1008   vec<tree, va_gc> *vbases;
1009   int i;
1010   int uses_unions_or_anon_p = 0;
1011 
1012   /* Build up a list of initializations.  The TREE_PURPOSE of entry
1013      will be the subobject (a FIELD_DECL or BINFO) to initialize.  The
1014      TREE_VALUE will be the constructor arguments, or NULL if no
1015      explicit initialization was provided.  */
1016   sorted_inits = NULL_TREE;
1017 
1018   /* Process the virtual bases.  */
1019   for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
1020        vec_safe_iterate (vbases, i, &base); i++)
1021     sorted_inits = tree_cons (base, NULL_TREE, sorted_inits);
1022 
1023   /* Process the direct bases.  */
1024   for (binfo = TYPE_BINFO (t), i = 0;
1025        BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
1026     if (!BINFO_VIRTUAL_P (base_binfo))
1027       sorted_inits = tree_cons (base_binfo, NULL_TREE, sorted_inits);
1028 
1029   /* Process the non-static data members.  */
1030   sorted_inits = build_field_list (t, sorted_inits, &uses_unions_or_anon_p);
1031   /* Reverse the entire list of initializations, so that they are in
1032      the order that they will actually be performed.  */
1033   sorted_inits = nreverse (sorted_inits);
1034 
1035   /* If the user presented the initializers in an order different from
1036      that in which they will actually occur, we issue a warning.  Keep
1037      track of the next subobject which can be explicitly initialized
1038      without issuing a warning.  */
1039   next_subobject = sorted_inits;
1040 
1041   /* Go through the explicit initializers, filling in TREE_PURPOSE in
1042      the SORTED_INITS.  */
1043   for (init = mem_inits; init; init = TREE_CHAIN (init))
1044     {
1045       tree subobject;
1046       tree subobject_init;
1047 
1048       subobject = TREE_PURPOSE (init);
1049 
1050       /* If the explicit initializers are in sorted order, then
1051 	 SUBOBJECT will be NEXT_SUBOBJECT, or something following
1052 	 it.  */
1053       for (subobject_init = next_subobject;
1054 	   subobject_init;
1055 	   subobject_init = TREE_CHAIN (subobject_init))
1056 	if (TREE_PURPOSE (subobject_init) == subobject)
1057 	  break;
1058 
1059       /* Issue a warning if the explicit initializer order does not
1060 	 match that which will actually occur.
1061 	 ??? Are all these on the correct lines?  */
1062       if (warn_reorder && !subobject_init)
1063 	{
1064 	  if (TREE_CODE (TREE_PURPOSE (next_subobject)) == FIELD_DECL)
1065 	    warning_at (DECL_SOURCE_LOCATION (TREE_PURPOSE (next_subobject)),
1066 			OPT_Wreorder, "%qD will be initialized after",
1067 			TREE_PURPOSE (next_subobject));
1068 	  else
1069 	    warning (OPT_Wreorder, "base %qT will be initialized after",
1070 		     TREE_PURPOSE (next_subobject));
1071 	  if (TREE_CODE (subobject) == FIELD_DECL)
1072 	    warning_at (DECL_SOURCE_LOCATION (subobject),
1073 			OPT_Wreorder, "  %q#D", subobject);
1074 	  else
1075 	    warning (OPT_Wreorder, "  base %qT", subobject);
1076 	  warning_at (DECL_SOURCE_LOCATION (current_function_decl),
1077 		      OPT_Wreorder, "  when initialized here");
1078 	}
1079 
1080       /* Look again, from the beginning of the list.  */
1081       if (!subobject_init)
1082 	{
1083 	  subobject_init = sorted_inits;
1084 	  while (TREE_PURPOSE (subobject_init) != subobject)
1085 	    subobject_init = TREE_CHAIN (subobject_init);
1086 	}
1087 
1088       /* It is invalid to initialize the same subobject more than
1089 	 once.  */
1090       if (TREE_VALUE (subobject_init))
1091 	{
1092 	  if (TREE_CODE (subobject) == FIELD_DECL)
1093 	    error_at (DECL_SOURCE_LOCATION (current_function_decl),
1094 		      "multiple initializations given for %qD",
1095 		      subobject);
1096 	  else
1097 	    error_at (DECL_SOURCE_LOCATION (current_function_decl),
1098 		      "multiple initializations given for base %qT",
1099 		      subobject);
1100 	}
1101 
1102       /* Record the initialization.  */
1103       TREE_VALUE (subobject_init) = TREE_VALUE (init);
1104       next_subobject = subobject_init;
1105     }
1106 
1107   /* [class.base.init]
1108 
1109      If a ctor-initializer specifies more than one mem-initializer for
1110      multiple members of the same union (including members of
1111      anonymous unions), the ctor-initializer is ill-formed.
1112 
1113      Here we also splice out uninitialized union members.  */
1114   if (uses_unions_or_anon_p)
1115     {
1116       tree *last_p = NULL;
1117       tree *p;
1118       for (p = &sorted_inits; *p; )
1119 	{
1120 	  tree field;
1121 	  tree ctx;
1122 
1123 	  init = *p;
1124 
1125 	  field = TREE_PURPOSE (init);
1126 
1127 	  /* Skip base classes.  */
1128 	  if (TREE_CODE (field) != FIELD_DECL)
1129 	    goto next;
1130 
1131 	  /* If this is an anonymous aggregate with no explicit initializer,
1132 	     splice it out.  */
1133 	  if (!TREE_VALUE (init) && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1134 	    goto splice;
1135 
1136 	  /* See if this field is a member of a union, or a member of a
1137 	     structure contained in a union, etc.  */
1138 	  ctx = innermost_aggr_scope (field);
1139 
1140 	  /* If this field is not a member of a union, skip it.  */
1141 	  if (TREE_CODE (ctx) != UNION_TYPE
1142 	      && !ANON_AGGR_TYPE_P (ctx))
1143 	    goto next;
1144 
1145 	  /* If this union member has no explicit initializer and no NSDMI,
1146 	     splice it out.  */
1147 	  if (TREE_VALUE (init) || DECL_INITIAL (field))
1148 	    /* OK.  */;
1149 	  else
1150 	    goto splice;
1151 
1152 	  /* It's only an error if we have two initializers for the same
1153 	     union type.  */
1154 	  if (!last_p)
1155 	    {
1156 	      last_p = p;
1157 	      goto next;
1158 	    }
1159 
1160 	  /* See if LAST_FIELD and the field initialized by INIT are
1161 	     members of the same union (or the union itself). If so, there's
1162 	     a problem, unless they're actually members of the same structure
1163 	     which is itself a member of a union.  For example, given:
1164 
1165 	       union { struct { int i; int j; }; };
1166 
1167 	     initializing both `i' and `j' makes sense.  */
1168 	  ctx = common_enclosing_class
1169 	    (innermost_aggr_scope (field),
1170 	     innermost_aggr_scope (TREE_PURPOSE (*last_p)));
1171 
1172 	  if (ctx && (TREE_CODE (ctx) == UNION_TYPE
1173 		      || ctx == TREE_TYPE (TREE_PURPOSE (*last_p))))
1174 	    {
1175 	      /* A mem-initializer hides an NSDMI.  */
1176 	      if (TREE_VALUE (init) && !TREE_VALUE (*last_p))
1177 		*last_p = TREE_CHAIN (*last_p);
1178 	      else if (TREE_VALUE (*last_p) && !TREE_VALUE (init))
1179 		goto splice;
1180 	      else
1181 		{
1182 		  error_at (DECL_SOURCE_LOCATION (current_function_decl),
1183 			    "initializations for multiple members of %qT",
1184 			    ctx);
1185 		  goto splice;
1186 		}
1187 	    }
1188 
1189 	  last_p = p;
1190 
1191 	next:
1192 	  p = &TREE_CHAIN (*p);
1193 	  continue;
1194 	splice:
1195 	  *p = TREE_CHAIN (*p);
1196 	  continue;
1197 	}
1198     }
1199 
1200   return sorted_inits;
1201 }
1202 
1203 /* Callback for cp_walk_tree to mark all PARM_DECLs in a tree as read.  */
1204 
1205 static tree
mark_exp_read_r(tree * tp,int *,void *)1206 mark_exp_read_r (tree *tp, int *, void *)
1207 {
1208   tree t = *tp;
1209   if (TREE_CODE (t) == PARM_DECL)
1210     mark_exp_read (t);
1211   return NULL_TREE;
1212 }
1213 
1214 /* Initialize all bases and members of CURRENT_CLASS_TYPE.  MEM_INITS
1215    is a TREE_LIST giving the explicit mem-initializer-list for the
1216    constructor.  The TREE_PURPOSE of each entry is a subobject (a
1217    FIELD_DECL or a BINFO) of the CURRENT_CLASS_TYPE.  The TREE_VALUE
1218    is a TREE_LIST giving the arguments to the constructor or
1219    void_type_node for an empty list of arguments.  */
1220 
1221 void
emit_mem_initializers(tree mem_inits)1222 emit_mem_initializers (tree mem_inits)
1223 {
1224   int flags = LOOKUP_NORMAL;
1225 
1226   /* We will already have issued an error message about the fact that
1227      the type is incomplete.  */
1228   if (!COMPLETE_TYPE_P (current_class_type))
1229     return;
1230 
1231   if (mem_inits
1232       && TYPE_P (TREE_PURPOSE (mem_inits))
1233       && same_type_p (TREE_PURPOSE (mem_inits), current_class_type))
1234     {
1235       /* Delegating constructor. */
1236       gcc_assert (TREE_CHAIN (mem_inits) == NULL_TREE);
1237       perform_target_ctor (TREE_VALUE (mem_inits));
1238       return;
1239     }
1240 
1241   if (DECL_DEFAULTED_FN (current_function_decl)
1242       && ! DECL_INHERITED_CTOR (current_function_decl))
1243     flags |= LOOKUP_DEFAULTED;
1244 
1245   /* Sort the mem-initializers into the order in which the
1246      initializations should be performed.  */
1247   mem_inits = sort_mem_initializers (current_class_type, mem_inits);
1248 
1249   in_base_initializer = 1;
1250 
1251   /* Initialize base classes.  */
1252   for (; (mem_inits
1253 	  && TREE_CODE (TREE_PURPOSE (mem_inits)) != FIELD_DECL);
1254        mem_inits = TREE_CHAIN (mem_inits))
1255     {
1256       tree subobject = TREE_PURPOSE (mem_inits);
1257       tree arguments = TREE_VALUE (mem_inits);
1258 
1259       /* We already have issued an error message.  */
1260       if (arguments == error_mark_node)
1261 	continue;
1262 
1263       /* Suppress access control when calling the inherited ctor.  */
1264       bool inherited_base = (DECL_INHERITED_CTOR (current_function_decl)
1265 			     && flag_new_inheriting_ctors
1266 			     && arguments);
1267       if (inherited_base)
1268 	push_deferring_access_checks (dk_deferred);
1269 
1270       if (arguments == NULL_TREE)
1271 	{
1272 	  /* If these initializations are taking place in a copy constructor,
1273 	     the base class should probably be explicitly initialized if there
1274 	     is a user-defined constructor in the base class (other than the
1275 	     default constructor, which will be called anyway).  */
1276 	  if (extra_warnings
1277 	      && DECL_COPY_CONSTRUCTOR_P (current_function_decl)
1278 	      && type_has_user_nondefault_constructor (BINFO_TYPE (subobject)))
1279 	    warning_at (DECL_SOURCE_LOCATION (current_function_decl),
1280 			OPT_Wextra, "base class %q#T should be explicitly "
1281 			"initialized in the copy constructor",
1282 			BINFO_TYPE (subobject));
1283 	}
1284 
1285       /* Initialize the base.  */
1286       if (!BINFO_VIRTUAL_P (subobject))
1287 	{
1288 	  tree base_addr;
1289 
1290 	  base_addr = build_base_path (PLUS_EXPR, current_class_ptr,
1291 				       subobject, 1, tf_warning_or_error);
1292 	  expand_aggr_init_1 (subobject, NULL_TREE,
1293 			      cp_build_fold_indirect_ref (base_addr),
1294 			      arguments,
1295 			      flags,
1296                               tf_warning_or_error);
1297 	  expand_cleanup_for_base (subobject, NULL_TREE);
1298 	}
1299       else if (!ABSTRACT_CLASS_TYPE_P (current_class_type))
1300 	/* C++14 DR1658 Means we do not have to construct vbases of
1301 	   abstract classes.  */
1302 	construct_virtual_base (subobject, arguments);
1303       else
1304 	/* When not constructing vbases of abstract classes, at least mark
1305 	   the arguments expressions as read to avoid
1306 	   -Wunused-but-set-parameter false positives.  */
1307 	cp_walk_tree (&arguments, mark_exp_read_r, NULL, NULL);
1308 
1309       if (inherited_base)
1310 	pop_deferring_access_checks ();
1311     }
1312   in_base_initializer = 0;
1313 
1314   /* Initialize the vptrs.  */
1315   initialize_vtbl_ptrs (current_class_ptr);
1316 
1317   /* Initialize the data members.  */
1318   while (mem_inits)
1319     {
1320       perform_member_init (TREE_PURPOSE (mem_inits),
1321 			   TREE_VALUE (mem_inits));
1322       mem_inits = TREE_CHAIN (mem_inits);
1323     }
1324 }
1325 
1326 /* Returns the address of the vtable (i.e., the value that should be
1327    assigned to the vptr) for BINFO.  */
1328 
1329 tree
build_vtbl_address(tree binfo)1330 build_vtbl_address (tree binfo)
1331 {
1332   tree binfo_for = binfo;
1333   tree vtbl;
1334 
1335   if (BINFO_VPTR_INDEX (binfo) && BINFO_VIRTUAL_P (binfo))
1336     /* If this is a virtual primary base, then the vtable we want to store
1337        is that for the base this is being used as the primary base of.  We
1338        can't simply skip the initialization, because we may be expanding the
1339        inits of a subobject constructor where the virtual base layout
1340        can be different.  */
1341     while (BINFO_PRIMARY_P (binfo_for))
1342       binfo_for = BINFO_INHERITANCE_CHAIN (binfo_for);
1343 
1344   /* Figure out what vtable BINFO's vtable is based on, and mark it as
1345      used.  */
1346   vtbl = get_vtbl_decl_for_binfo (binfo_for);
1347   TREE_USED (vtbl) = true;
1348 
1349   /* Now compute the address to use when initializing the vptr.  */
1350   vtbl = unshare_expr (BINFO_VTABLE (binfo_for));
1351   if (VAR_P (vtbl))
1352     vtbl = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (vtbl)), vtbl);
1353 
1354   return vtbl;
1355 }
1356 
1357 /* This code sets up the virtual function tables appropriate for
1358    the pointer DECL.  It is a one-ply initialization.
1359 
1360    BINFO is the exact type that DECL is supposed to be.  In
1361    multiple inheritance, this might mean "C's A" if C : A, B.  */
1362 
1363 static void
expand_virtual_init(tree binfo,tree decl)1364 expand_virtual_init (tree binfo, tree decl)
1365 {
1366   tree vtbl, vtbl_ptr;
1367   tree vtt_index;
1368 
1369   /* Compute the initializer for vptr.  */
1370   vtbl = build_vtbl_address (binfo);
1371 
1372   /* We may get this vptr from a VTT, if this is a subobject
1373      constructor or subobject destructor.  */
1374   vtt_index = BINFO_VPTR_INDEX (binfo);
1375   if (vtt_index)
1376     {
1377       tree vtbl2;
1378       tree vtt_parm;
1379 
1380       /* Compute the value to use, when there's a VTT.  */
1381       vtt_parm = current_vtt_parm;
1382       vtbl2 = fold_build_pointer_plus (vtt_parm, vtt_index);
1383       vtbl2 = cp_build_fold_indirect_ref (vtbl2);
1384       vtbl2 = convert (TREE_TYPE (vtbl), vtbl2);
1385 
1386       /* The actual initializer is the VTT value only in the subobject
1387 	 constructor.  In maybe_clone_body we'll substitute NULL for
1388 	 the vtt_parm in the case of the non-subobject constructor.  */
1389       vtbl = build_if_in_charge (vtbl, vtbl2);
1390     }
1391 
1392   /* Compute the location of the vtpr.  */
1393   vtbl_ptr = build_vfield_ref (cp_build_fold_indirect_ref (decl),
1394 			       TREE_TYPE (binfo));
1395   gcc_assert (vtbl_ptr != error_mark_node);
1396 
1397   /* Assign the vtable to the vptr.  */
1398   vtbl = convert_force (TREE_TYPE (vtbl_ptr), vtbl, 0, tf_warning_or_error);
1399   finish_expr_stmt (cp_build_modify_expr (input_location, vtbl_ptr, NOP_EXPR,
1400 					  vtbl, tf_warning_or_error));
1401 }
1402 
1403 /* If an exception is thrown in a constructor, those base classes already
1404    constructed must be destroyed.  This function creates the cleanup
1405    for BINFO, which has just been constructed.  If FLAG is non-NULL,
1406    it is a DECL which is nonzero when this base needs to be
1407    destroyed.  */
1408 
1409 static void
expand_cleanup_for_base(tree binfo,tree flag)1410 expand_cleanup_for_base (tree binfo, tree flag)
1411 {
1412   tree expr;
1413 
1414   if (!type_build_dtor_call (BINFO_TYPE (binfo)))
1415     return;
1416 
1417   /* Call the destructor.  */
1418   expr = build_special_member_call (current_class_ref,
1419 				    base_dtor_identifier,
1420 				    NULL,
1421 				    binfo,
1422 				    LOOKUP_NORMAL | LOOKUP_NONVIRTUAL,
1423                                     tf_warning_or_error);
1424 
1425   if (TYPE_HAS_TRIVIAL_DESTRUCTOR (BINFO_TYPE (binfo)))
1426     return;
1427 
1428   if (flag)
1429     expr = fold_build3_loc (input_location,
1430 			COND_EXPR, void_type_node,
1431 			c_common_truthvalue_conversion (input_location, flag),
1432 			expr, integer_zero_node);
1433 
1434   finish_eh_cleanup (expr);
1435 }
1436 
1437 /* Construct the virtual base-class VBASE passing the ARGUMENTS to its
1438    constructor.  */
1439 
1440 static void
construct_virtual_base(tree vbase,tree arguments)1441 construct_virtual_base (tree vbase, tree arguments)
1442 {
1443   tree inner_if_stmt;
1444   tree exp;
1445   tree flag;
1446 
1447   /* If there are virtual base classes with destructors, we need to
1448      emit cleanups to destroy them if an exception is thrown during
1449      the construction process.  These exception regions (i.e., the
1450      period during which the cleanups must occur) begin from the time
1451      the construction is complete to the end of the function.  If we
1452      create a conditional block in which to initialize the
1453      base-classes, then the cleanup region for the virtual base begins
1454      inside a block, and ends outside of that block.  This situation
1455      confuses the sjlj exception-handling code.  Therefore, we do not
1456      create a single conditional block, but one for each
1457      initialization.  (That way the cleanup regions always begin
1458      in the outer block.)  We trust the back end to figure out
1459      that the FLAG will not change across initializations, and
1460      avoid doing multiple tests.  */
1461   flag = DECL_CHAIN (DECL_ARGUMENTS (current_function_decl));
1462   inner_if_stmt = begin_if_stmt ();
1463   finish_if_stmt_cond (flag, inner_if_stmt);
1464 
1465   /* Compute the location of the virtual base.  If we're
1466      constructing virtual bases, then we must be the most derived
1467      class.  Therefore, we don't have to look up the virtual base;
1468      we already know where it is.  */
1469   exp = convert_to_base_statically (current_class_ref, vbase);
1470 
1471   expand_aggr_init_1 (vbase, current_class_ref, exp, arguments,
1472 		      0, tf_warning_or_error);
1473   finish_then_clause (inner_if_stmt);
1474   finish_if_stmt (inner_if_stmt);
1475 
1476   expand_cleanup_for_base (vbase, flag);
1477 }
1478 
1479 /* Find the context in which this FIELD can be initialized.  */
1480 
1481 static tree
initializing_context(tree field)1482 initializing_context (tree field)
1483 {
1484   tree t = DECL_CONTEXT (field);
1485 
1486   /* Anonymous union members can be initialized in the first enclosing
1487      non-anonymous union context.  */
1488   while (t && ANON_AGGR_TYPE_P (t))
1489     t = TYPE_CONTEXT (t);
1490   return t;
1491 }
1492 
1493 /* Function to give error message if member initialization specification
1494    is erroneous.  FIELD is the member we decided to initialize.
1495    TYPE is the type for which the initialization is being performed.
1496    FIELD must be a member of TYPE.
1497 
1498    MEMBER_NAME is the name of the member.  */
1499 
1500 static int
member_init_ok_or_else(tree field,tree type,tree member_name)1501 member_init_ok_or_else (tree field, tree type, tree member_name)
1502 {
1503   if (field == error_mark_node)
1504     return 0;
1505   if (!field)
1506     {
1507       error ("class %qT does not have any field named %qD", type,
1508 	     member_name);
1509       return 0;
1510     }
1511   if (VAR_P (field))
1512     {
1513       error ("%q#D is a static data member; it can only be "
1514 	     "initialized at its definition",
1515 	     field);
1516       return 0;
1517     }
1518   if (TREE_CODE (field) != FIELD_DECL)
1519     {
1520       error ("%q#D is not a non-static data member of %qT",
1521 	     field, type);
1522       return 0;
1523     }
1524   if (initializing_context (field) != type)
1525     {
1526       error ("class %qT does not have any field named %qD", type,
1527 		member_name);
1528       return 0;
1529     }
1530 
1531   return 1;
1532 }
1533 
1534 /* NAME is a FIELD_DECL, an IDENTIFIER_NODE which names a field, or it
1535    is a _TYPE node or TYPE_DECL which names a base for that type.
1536    Check the validity of NAME, and return either the base _TYPE, base
1537    binfo, or the FIELD_DECL of the member.  If NAME is invalid, return
1538    NULL_TREE and issue a diagnostic.
1539 
1540    An old style unnamed direct single base construction is permitted,
1541    where NAME is NULL.  */
1542 
1543 tree
expand_member_init(tree name)1544 expand_member_init (tree name)
1545 {
1546   tree basetype;
1547   tree field;
1548 
1549   if (!current_class_ref)
1550     return NULL_TREE;
1551 
1552   if (!name)
1553     {
1554       /* This is an obsolete unnamed base class initializer.  The
1555 	 parser will already have warned about its use.  */
1556       switch (BINFO_N_BASE_BINFOS (TYPE_BINFO (current_class_type)))
1557 	{
1558 	case 0:
1559 	  error ("unnamed initializer for %qT, which has no base classes",
1560 		 current_class_type);
1561 	  return NULL_TREE;
1562 	case 1:
1563 	  basetype = BINFO_TYPE
1564 	    (BINFO_BASE_BINFO (TYPE_BINFO (current_class_type), 0));
1565 	  break;
1566 	default:
1567 	  error ("unnamed initializer for %qT, which uses multiple inheritance",
1568 		 current_class_type);
1569 	  return NULL_TREE;
1570       }
1571     }
1572   else if (TYPE_P (name))
1573     {
1574       basetype = TYPE_MAIN_VARIANT (name);
1575       name = TYPE_NAME (name);
1576     }
1577   else if (TREE_CODE (name) == TYPE_DECL)
1578     basetype = TYPE_MAIN_VARIANT (TREE_TYPE (name));
1579   else
1580     basetype = NULL_TREE;
1581 
1582   if (basetype)
1583     {
1584       tree class_binfo;
1585       tree direct_binfo;
1586       tree virtual_binfo;
1587       int i;
1588 
1589       if (current_template_parms
1590 	  || same_type_p (basetype, current_class_type))
1591 	  return basetype;
1592 
1593       class_binfo = TYPE_BINFO (current_class_type);
1594       direct_binfo = NULL_TREE;
1595       virtual_binfo = NULL_TREE;
1596 
1597       /* Look for a direct base.  */
1598       for (i = 0; BINFO_BASE_ITERATE (class_binfo, i, direct_binfo); ++i)
1599 	if (SAME_BINFO_TYPE_P (BINFO_TYPE (direct_binfo), basetype))
1600 	  break;
1601 
1602       /* Look for a virtual base -- unless the direct base is itself
1603 	 virtual.  */
1604       if (!direct_binfo || !BINFO_VIRTUAL_P (direct_binfo))
1605 	virtual_binfo = binfo_for_vbase (basetype, current_class_type);
1606 
1607       /* [class.base.init]
1608 
1609 	 If a mem-initializer-id is ambiguous because it designates
1610 	 both a direct non-virtual base class and an inherited virtual
1611 	 base class, the mem-initializer is ill-formed.  */
1612       if (direct_binfo && virtual_binfo)
1613 	{
1614 	  error ("%qD is both a direct base and an indirect virtual base",
1615 		 basetype);
1616 	  return NULL_TREE;
1617 	}
1618 
1619       if (!direct_binfo && !virtual_binfo)
1620 	{
1621 	  if (CLASSTYPE_VBASECLASSES (current_class_type))
1622 	    error ("type %qT is not a direct or virtual base of %qT",
1623 		   basetype, current_class_type);
1624 	  else
1625 	    error ("type %qT is not a direct base of %qT",
1626 		   basetype, current_class_type);
1627 	  return NULL_TREE;
1628 	}
1629 
1630       return direct_binfo ? direct_binfo : virtual_binfo;
1631     }
1632   else
1633     {
1634       if (identifier_p (name))
1635 	field = lookup_field (current_class_type, name, 1, false);
1636       else
1637 	field = name;
1638 
1639       if (member_init_ok_or_else (field, current_class_type, name))
1640 	return field;
1641     }
1642 
1643   return NULL_TREE;
1644 }
1645 
1646 /* This is like `expand_member_init', only it stores one aggregate
1647    value into another.
1648 
1649    INIT comes in two flavors: it is either a value which
1650    is to be stored in EXP, or it is a parameter list
1651    to go to a constructor, which will operate on EXP.
1652    If INIT is not a parameter list for a constructor, then set
1653    LOOKUP_ONLYCONVERTING.
1654    If FLAGS is LOOKUP_ONLYCONVERTING then it is the = init form of
1655    the initializer, if FLAGS is 0, then it is the (init) form.
1656    If `init' is a CONSTRUCTOR, then we emit a warning message,
1657    explaining that such initializations are invalid.
1658 
1659    If INIT resolves to a CALL_EXPR which happens to return
1660    something of the type we are looking for, then we know
1661    that we can safely use that call to perform the
1662    initialization.
1663 
1664    The virtual function table pointer cannot be set up here, because
1665    we do not really know its type.
1666 
1667    This never calls operator=().
1668 
1669    When initializing, nothing is CONST.
1670 
1671    A default copy constructor may have to be used to perform the
1672    initialization.
1673 
1674    A constructor or a conversion operator may have to be used to
1675    perform the initialization, but not both, as it would be ambiguous.  */
1676 
1677 tree
build_aggr_init(tree exp,tree init,int flags,tsubst_flags_t complain)1678 build_aggr_init (tree exp, tree init, int flags, tsubst_flags_t complain)
1679 {
1680   tree stmt_expr;
1681   tree compound_stmt;
1682   int destroy_temps;
1683   tree type = TREE_TYPE (exp);
1684   int was_const = TREE_READONLY (exp);
1685   int was_volatile = TREE_THIS_VOLATILE (exp);
1686   int is_global;
1687 
1688   if (init == error_mark_node)
1689     return error_mark_node;
1690 
1691   location_t init_loc = (init
1692 			 ? EXPR_LOC_OR_LOC (init, input_location)
1693 			 : location_of (exp));
1694 
1695   TREE_READONLY (exp) = 0;
1696   TREE_THIS_VOLATILE (exp) = 0;
1697 
1698   if (TREE_CODE (type) == ARRAY_TYPE)
1699     {
1700       tree itype = init ? TREE_TYPE (init) : NULL_TREE;
1701       int from_array = 0;
1702 
1703       if (VAR_P (exp) && DECL_DECOMPOSITION_P (exp))
1704 	{
1705 	  from_array = 1;
1706 	  init = mark_rvalue_use (init);
1707 	  if (init && DECL_P (init)
1708 	      && !(flags & LOOKUP_ONLYCONVERTING))
1709 	    {
1710 	      /* Wrap the initializer in a CONSTRUCTOR so that build_vec_init
1711 		 recognizes it as direct-initialization.  */
1712 	      init = build_constructor_single (init_list_type_node,
1713 					       NULL_TREE, init);
1714 	      CONSTRUCTOR_IS_DIRECT_INIT (init) = true;
1715 	    }
1716 	}
1717       else
1718 	{
1719 	  /* Must arrange to initialize each element of EXP
1720 	     from elements of INIT.  */
1721 	  if (cv_qualified_p (type))
1722 	    TREE_TYPE (exp) = cv_unqualified (type);
1723 	  if (itype && cv_qualified_p (itype))
1724 	    TREE_TYPE (init) = cv_unqualified (itype);
1725 	  from_array = (itype && same_type_p (TREE_TYPE (init),
1726 					      TREE_TYPE (exp)));
1727 
1728 	  if (init && !BRACE_ENCLOSED_INITIALIZER_P (init)
1729 	      && (!from_array
1730 		  || (TREE_CODE (init) != CONSTRUCTOR
1731 		      /* Can happen, eg, handling the compound-literals
1732 			 extension (ext/complit12.C).  */
1733 		      && TREE_CODE (init) != TARGET_EXPR)))
1734 	    {
1735 	      if (complain & tf_error)
1736 		error_at (init_loc, "array must be initialized "
1737 			  "with a brace-enclosed initializer");
1738 	      return error_mark_node;
1739 	    }
1740 	}
1741 
1742       stmt_expr = build_vec_init (exp, NULL_TREE, init,
1743 				  /*explicit_value_init_p=*/false,
1744 				  from_array,
1745                                   complain);
1746       TREE_READONLY (exp) = was_const;
1747       TREE_THIS_VOLATILE (exp) = was_volatile;
1748       TREE_TYPE (exp) = type;
1749       /* Restore the type of init unless it was used directly.  */
1750       if (init && TREE_CODE (stmt_expr) != INIT_EXPR)
1751 	TREE_TYPE (init) = itype;
1752       return stmt_expr;
1753     }
1754 
1755   if (init && init != void_type_node
1756       && TREE_CODE (init) != TREE_LIST
1757       && !(TREE_CODE (init) == TARGET_EXPR
1758 	   && TARGET_EXPR_DIRECT_INIT_P (init))
1759       && !DIRECT_LIST_INIT_P (init))
1760     flags |= LOOKUP_ONLYCONVERTING;
1761 
1762   if ((VAR_P (exp) || TREE_CODE (exp) == PARM_DECL)
1763       && !lookup_attribute ("warn_unused", TYPE_ATTRIBUTES (type)))
1764     /* Just know that we've seen something for this node.  */
1765     TREE_USED (exp) = 1;
1766 
1767   is_global = begin_init_stmts (&stmt_expr, &compound_stmt);
1768   destroy_temps = stmts_are_full_exprs_p ();
1769   current_stmt_tree ()->stmts_are_full_exprs_p = 0;
1770   expand_aggr_init_1 (TYPE_BINFO (type), exp, exp,
1771 		      init, LOOKUP_NORMAL|flags, complain);
1772   stmt_expr = finish_init_stmts (is_global, stmt_expr, compound_stmt);
1773   current_stmt_tree ()->stmts_are_full_exprs_p = destroy_temps;
1774   TREE_READONLY (exp) = was_const;
1775   TREE_THIS_VOLATILE (exp) = was_volatile;
1776 
1777   return stmt_expr;
1778 }
1779 
1780 static void
expand_default_init(tree binfo,tree true_exp,tree exp,tree init,int flags,tsubst_flags_t complain)1781 expand_default_init (tree binfo, tree true_exp, tree exp, tree init, int flags,
1782                      tsubst_flags_t complain)
1783 {
1784   tree type = TREE_TYPE (exp);
1785 
1786   /* It fails because there may not be a constructor which takes
1787      its own type as the first (or only parameter), but which does
1788      take other types via a conversion.  So, if the thing initializing
1789      the expression is a unit element of type X, first try X(X&),
1790      followed by initialization by X.  If neither of these work
1791      out, then look hard.  */
1792   tree rval;
1793   vec<tree, va_gc> *parms;
1794 
1795   /* If we have direct-initialization from an initializer list, pull
1796      it out of the TREE_LIST so the code below can see it.  */
1797   if (init && TREE_CODE (init) == TREE_LIST
1798       && DIRECT_LIST_INIT_P (TREE_VALUE (init)))
1799     {
1800       gcc_checking_assert ((flags & LOOKUP_ONLYCONVERTING) == 0
1801 			   && TREE_CHAIN (init) == NULL_TREE);
1802       init = TREE_VALUE (init);
1803       /* Only call reshape_init if it has not been called earlier
1804 	 by the callers.  */
1805       if (BRACE_ENCLOSED_INITIALIZER_P (init) && CP_AGGREGATE_TYPE_P (type))
1806 	init = reshape_init (type, init, complain);
1807     }
1808 
1809   if (init && BRACE_ENCLOSED_INITIALIZER_P (init)
1810       && CP_AGGREGATE_TYPE_P (type))
1811     /* A brace-enclosed initializer for an aggregate.  In C++0x this can
1812        happen for direct-initialization, too.  */
1813     init = digest_init (type, init, complain);
1814 
1815   /* A CONSTRUCTOR of the target's type is a previously digested
1816      initializer, whether that happened just above or in
1817      cp_parser_late_parsing_nsdmi.
1818 
1819      A TARGET_EXPR with TARGET_EXPR_DIRECT_INIT_P or TARGET_EXPR_LIST_INIT_P
1820      set represents the whole initialization, so we shouldn't build up
1821      another ctor call.  */
1822   if (init
1823       && (TREE_CODE (init) == CONSTRUCTOR
1824 	  || (TREE_CODE (init) == TARGET_EXPR
1825 	      && (TARGET_EXPR_DIRECT_INIT_P (init)
1826 		  || TARGET_EXPR_LIST_INIT_P (init))))
1827       && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (init), type))
1828     {
1829       /* Early initialization via a TARGET_EXPR only works for
1830 	 complete objects.  */
1831       gcc_assert (TREE_CODE (init) == CONSTRUCTOR || true_exp == exp);
1832 
1833       init = build2 (INIT_EXPR, TREE_TYPE (exp), exp, init);
1834       TREE_SIDE_EFFECTS (init) = 1;
1835       finish_expr_stmt (init);
1836       return;
1837     }
1838 
1839   if (init && TREE_CODE (init) != TREE_LIST
1840       && (flags & LOOKUP_ONLYCONVERTING))
1841     {
1842       /* Base subobjects should only get direct-initialization.  */
1843       gcc_assert (true_exp == exp);
1844 
1845       if (flags & DIRECT_BIND)
1846 	/* Do nothing.  We hit this in two cases:  Reference initialization,
1847 	   where we aren't initializing a real variable, so we don't want
1848 	   to run a new constructor; and catching an exception, where we
1849 	   have already built up the constructor call so we could wrap it
1850 	   in an exception region.  */;
1851       else
1852 	init = ocp_convert (type, init, CONV_IMPLICIT|CONV_FORCE_TEMP,
1853 			    flags, complain);
1854 
1855       if (TREE_CODE (init) == MUST_NOT_THROW_EXPR)
1856 	/* We need to protect the initialization of a catch parm with a
1857 	   call to terminate(), which shows up as a MUST_NOT_THROW_EXPR
1858 	   around the TARGET_EXPR for the copy constructor.  See
1859 	   initialize_handler_parm.  */
1860 	{
1861 	  TREE_OPERAND (init, 0) = build2 (INIT_EXPR, TREE_TYPE (exp), exp,
1862 					   TREE_OPERAND (init, 0));
1863 	  TREE_TYPE (init) = void_type_node;
1864 	}
1865       else
1866 	init = build2 (INIT_EXPR, TREE_TYPE (exp), exp, init);
1867       TREE_SIDE_EFFECTS (init) = 1;
1868       finish_expr_stmt (init);
1869       return;
1870     }
1871 
1872   if (init == NULL_TREE)
1873     parms = NULL;
1874   else if (TREE_CODE (init) == TREE_LIST && !TREE_TYPE (init))
1875     {
1876       parms = make_tree_vector ();
1877       for (; init != NULL_TREE; init = TREE_CHAIN (init))
1878 	vec_safe_push (parms, TREE_VALUE (init));
1879     }
1880   else
1881     parms = make_tree_vector_single (init);
1882 
1883   if (exp == current_class_ref && current_function_decl
1884       && DECL_HAS_IN_CHARGE_PARM_P (current_function_decl))
1885     {
1886       /* Delegating constructor. */
1887       tree complete;
1888       tree base;
1889       tree elt; unsigned i;
1890 
1891       /* Unshare the arguments for the second call.  */
1892       vec<tree, va_gc> *parms2 = make_tree_vector ();
1893       FOR_EACH_VEC_SAFE_ELT (parms, i, elt)
1894 	{
1895 	  elt = break_out_target_exprs (elt);
1896 	  vec_safe_push (parms2, elt);
1897 	}
1898       complete = build_special_member_call (exp, complete_ctor_identifier,
1899 					    &parms2, binfo, flags,
1900 					    complain);
1901       complete = fold_build_cleanup_point_expr (void_type_node, complete);
1902       release_tree_vector (parms2);
1903 
1904       base = build_special_member_call (exp, base_ctor_identifier,
1905 					&parms, binfo, flags,
1906 					complain);
1907       base = fold_build_cleanup_point_expr (void_type_node, base);
1908       rval = build_if_in_charge (complete, base);
1909     }
1910    else
1911     {
1912       tree ctor_name = (true_exp == exp
1913 			? complete_ctor_identifier : base_ctor_identifier);
1914 
1915       rval = build_special_member_call (exp, ctor_name, &parms, binfo, flags,
1916 					complain);
1917     }
1918 
1919   if (parms != NULL)
1920     release_tree_vector (parms);
1921 
1922   if (exp == true_exp && TREE_CODE (rval) == CALL_EXPR)
1923     {
1924       tree fn = get_callee_fndecl (rval);
1925       if (fn && DECL_DECLARED_CONSTEXPR_P (fn))
1926 	{
1927 	  tree e = maybe_constant_init (rval, exp);
1928 	  if (TREE_CONSTANT (e))
1929 	    rval = build2 (INIT_EXPR, type, exp, e);
1930 	}
1931     }
1932 
1933   /* FIXME put back convert_to_void?  */
1934   if (TREE_SIDE_EFFECTS (rval))
1935     finish_expr_stmt (rval);
1936 }
1937 
1938 /* This function is responsible for initializing EXP with INIT
1939    (if any).
1940 
1941    BINFO is the binfo of the type for who we are performing the
1942    initialization.  For example, if W is a virtual base class of A and B,
1943    and C : A, B.
1944    If we are initializing B, then W must contain B's W vtable, whereas
1945    were we initializing C, W must contain C's W vtable.
1946 
1947    TRUE_EXP is nonzero if it is the true expression being initialized.
1948    In this case, it may be EXP, or may just contain EXP.  The reason we
1949    need this is because if EXP is a base element of TRUE_EXP, we
1950    don't necessarily know by looking at EXP where its virtual
1951    baseclass fields should really be pointing.  But we do know
1952    from TRUE_EXP.  In constructors, we don't know anything about
1953    the value being initialized.
1954 
1955    FLAGS is just passed to `build_new_method_call'.  See that function
1956    for its description.  */
1957 
1958 static void
expand_aggr_init_1(tree binfo,tree true_exp,tree exp,tree init,int flags,tsubst_flags_t complain)1959 expand_aggr_init_1 (tree binfo, tree true_exp, tree exp, tree init, int flags,
1960                     tsubst_flags_t complain)
1961 {
1962   tree type = TREE_TYPE (exp);
1963 
1964   gcc_assert (init != error_mark_node && type != error_mark_node);
1965   gcc_assert (building_stmt_list_p ());
1966 
1967   /* Use a function returning the desired type to initialize EXP for us.
1968      If the function is a constructor, and its first argument is
1969      NULL_TREE, know that it was meant for us--just slide exp on
1970      in and expand the constructor.  Constructors now come
1971      as TARGET_EXPRs.  */
1972 
1973   if (init && VAR_P (exp)
1974       && COMPOUND_LITERAL_P (init))
1975     {
1976       vec<tree, va_gc> *cleanups = NULL;
1977       /* If store_init_value returns NULL_TREE, the INIT has been
1978 	 recorded as the DECL_INITIAL for EXP.  That means there's
1979 	 nothing more we have to do.  */
1980       init = store_init_value (exp, init, &cleanups, flags);
1981       if (init)
1982 	finish_expr_stmt (init);
1983       gcc_assert (!cleanups);
1984       return;
1985     }
1986 
1987   /* List-initialization from {} becomes value-initialization for non-aggregate
1988      classes with default constructors.  Handle this here when we're
1989      initializing a base, so protected access works.  */
1990   if (exp != true_exp && init && TREE_CODE (init) == TREE_LIST)
1991     {
1992       tree elt = TREE_VALUE (init);
1993       if (DIRECT_LIST_INIT_P (elt)
1994 	  && CONSTRUCTOR_ELTS (elt) == 0
1995 	  && CLASSTYPE_NON_AGGREGATE (type)
1996 	  && TYPE_HAS_DEFAULT_CONSTRUCTOR (type))
1997 	init = void_type_node;
1998     }
1999 
2000   /* If an explicit -- but empty -- initializer list was present,
2001      that's value-initialization.  */
2002   if (init == void_type_node)
2003     {
2004       /* If the type has data but no user-provided ctor, we need to zero
2005 	 out the object.  */
2006       if (!type_has_user_provided_constructor (type)
2007 	  && !is_really_empty_class (type))
2008 	{
2009 	  tree field_size = NULL_TREE;
2010 	  if (exp != true_exp && CLASSTYPE_AS_BASE (type) != type)
2011 	    /* Don't clobber already initialized virtual bases.  */
2012 	    field_size = TYPE_SIZE (CLASSTYPE_AS_BASE (type));
2013 	  init = build_zero_init_1 (type, NULL_TREE, /*static_storage_p=*/false,
2014 				    field_size);
2015 	  init = build2 (INIT_EXPR, type, exp, init);
2016 	  finish_expr_stmt (init);
2017 	}
2018 
2019       /* If we don't need to mess with the constructor at all,
2020 	 then we're done.  */
2021       if (! type_build_ctor_call (type))
2022 	return;
2023 
2024       /* Otherwise fall through and call the constructor.  */
2025       init = NULL_TREE;
2026     }
2027 
2028   /* We know that expand_default_init can handle everything we want
2029      at this point.  */
2030   expand_default_init (binfo, true_exp, exp, init, flags, complain);
2031 }
2032 
2033 /* Report an error if TYPE is not a user-defined, class type.  If
2034    OR_ELSE is nonzero, give an error message.  */
2035 
2036 int
is_class_type(tree type,int or_else)2037 is_class_type (tree type, int or_else)
2038 {
2039   if (type == error_mark_node)
2040     return 0;
2041 
2042   if (! CLASS_TYPE_P (type))
2043     {
2044       if (or_else)
2045 	error ("%qT is not a class type", type);
2046       return 0;
2047     }
2048   return 1;
2049 }
2050 
2051 tree
get_type_value(tree name)2052 get_type_value (tree name)
2053 {
2054   if (name == error_mark_node)
2055     return NULL_TREE;
2056 
2057   if (IDENTIFIER_HAS_TYPE_VALUE (name))
2058     return IDENTIFIER_TYPE_VALUE (name);
2059   else
2060     return NULL_TREE;
2061 }
2062 
2063 /* Build a reference to a member of an aggregate.  This is not a C++
2064    `&', but really something which can have its address taken, and
2065    then act as a pointer to member, for example TYPE :: FIELD can have
2066    its address taken by saying & TYPE :: FIELD.  ADDRESS_P is true if
2067    this expression is the operand of "&".
2068 
2069    @@ Prints out lousy diagnostics for operator <typename>
2070    @@ fields.
2071 
2072    @@ This function should be rewritten and placed in search.c.  */
2073 
2074 tree
build_offset_ref(tree type,tree member,bool address_p,tsubst_flags_t complain)2075 build_offset_ref (tree type, tree member, bool address_p,
2076 		  tsubst_flags_t complain)
2077 {
2078   tree decl;
2079   tree basebinfo = NULL_TREE;
2080 
2081   /* class templates can come in as TEMPLATE_DECLs here.  */
2082   if (TREE_CODE (member) == TEMPLATE_DECL)
2083     return member;
2084 
2085   if (dependent_scope_p (type) || type_dependent_expression_p (member))
2086     return build_qualified_name (NULL_TREE, type, member,
2087 				  /*template_p=*/false);
2088 
2089   gcc_assert (TYPE_P (type));
2090   if (! is_class_type (type, 1))
2091     return error_mark_node;
2092 
2093   gcc_assert (DECL_P (member) || BASELINK_P (member));
2094   /* Callers should call mark_used before this point.  */
2095   gcc_assert (!DECL_P (member) || TREE_USED (member));
2096 
2097   type = TYPE_MAIN_VARIANT (type);
2098   if (!COMPLETE_OR_OPEN_TYPE_P (complete_type (type)))
2099     {
2100       if (complain & tf_error)
2101 	error ("incomplete type %qT does not have member %qD", type, member);
2102       return error_mark_node;
2103     }
2104 
2105   /* Entities other than non-static members need no further
2106      processing.  */
2107   if (TREE_CODE (member) == TYPE_DECL)
2108     return member;
2109   if (VAR_P (member) || TREE_CODE (member) == CONST_DECL)
2110     return convert_from_reference (member);
2111 
2112   if (TREE_CODE (member) == FIELD_DECL && DECL_C_BIT_FIELD (member))
2113     {
2114       if (complain & tf_error)
2115 	error ("invalid pointer to bit-field %qD", member);
2116       return error_mark_node;
2117     }
2118 
2119   /* Set up BASEBINFO for member lookup.  */
2120   decl = maybe_dummy_object (type, &basebinfo);
2121 
2122   /* A lot of this logic is now handled in lookup_member.  */
2123   if (BASELINK_P (member))
2124     {
2125       /* Go from the TREE_BASELINK to the member function info.  */
2126       tree t = BASELINK_FUNCTIONS (member);
2127 
2128       if (TREE_CODE (t) != TEMPLATE_ID_EXPR && !really_overloaded_fn (t))
2129 	{
2130 	  /* Get rid of a potential OVERLOAD around it.  */
2131 	  t = OVL_FIRST (t);
2132 
2133 	  /* Unique functions are handled easily.  */
2134 
2135 	  /* For non-static member of base class, we need a special rule
2136 	     for access checking [class.protected]:
2137 
2138 	       If the access is to form a pointer to member, the
2139 	       nested-name-specifier shall name the derived class
2140 	       (or any class derived from that class).  */
2141 	  bool ok;
2142 	  if (address_p && DECL_P (t)
2143 	      && DECL_NONSTATIC_MEMBER_P (t))
2144 	    ok = perform_or_defer_access_check (TYPE_BINFO (type), t, t,
2145 						complain);
2146 	  else
2147 	    ok = perform_or_defer_access_check (basebinfo, t, t,
2148 						complain);
2149 	  if (!ok)
2150 	    return error_mark_node;
2151 	  if (DECL_STATIC_FUNCTION_P (t))
2152 	    return t;
2153 	  member = t;
2154 	}
2155       else
2156 	TREE_TYPE (member) = unknown_type_node;
2157     }
2158   else if (address_p && TREE_CODE (member) == FIELD_DECL)
2159     {
2160       /* We need additional test besides the one in
2161 	 check_accessibility_of_qualified_id in case it is
2162 	 a pointer to non-static member.  */
2163       if (!perform_or_defer_access_check (TYPE_BINFO (type), member, member,
2164 					  complain))
2165 	return error_mark_node;
2166     }
2167 
2168   if (!address_p)
2169     {
2170       /* If MEMBER is non-static, then the program has fallen afoul of
2171 	 [expr.prim]:
2172 
2173 	   An id-expression that denotes a nonstatic data member or
2174 	   nonstatic member function of a class can only be used:
2175 
2176 	   -- as part of a class member access (_expr.ref_) in which the
2177 	   object-expression refers to the member's class or a class
2178 	   derived from that class, or
2179 
2180 	   -- to form a pointer to member (_expr.unary.op_), or
2181 
2182 	   -- in the body of a nonstatic member function of that class or
2183 	   of a class derived from that class (_class.mfct.nonstatic_), or
2184 
2185 	   -- in a mem-initializer for a constructor for that class or for
2186 	   a class derived from that class (_class.base.init_).  */
2187       if (DECL_NONSTATIC_MEMBER_FUNCTION_P (member))
2188 	{
2189 	  /* Build a representation of the qualified name suitable
2190 	     for use as the operand to "&" -- even though the "&" is
2191 	     not actually present.  */
2192 	  member = build2 (OFFSET_REF, TREE_TYPE (member), decl, member);
2193 	  /* In Microsoft mode, treat a non-static member function as if
2194 	     it were a pointer-to-member.  */
2195 	  if (flag_ms_extensions)
2196 	    {
2197 	      PTRMEM_OK_P (member) = 1;
2198 	      return cp_build_addr_expr (member, complain);
2199 	    }
2200 	  if (complain & tf_error)
2201 	    error ("invalid use of non-static member function %qD",
2202 		   TREE_OPERAND (member, 1));
2203 	  return error_mark_node;
2204 	}
2205       else if (TREE_CODE (member) == FIELD_DECL)
2206 	{
2207 	  if (complain & tf_error)
2208 	    error ("invalid use of non-static data member %qD", member);
2209 	  return error_mark_node;
2210 	}
2211       return member;
2212     }
2213 
2214   member = build2 (OFFSET_REF, TREE_TYPE (member), decl, member);
2215   PTRMEM_OK_P (member) = 1;
2216   return member;
2217 }
2218 
2219 /* If DECL is a scalar enumeration constant or variable with a
2220    constant initializer, return the initializer (or, its initializers,
2221    recursively); otherwise, return DECL.  If STRICT_P, the
2222    initializer is only returned if DECL is a
2223    constant-expression.  If RETURN_AGGREGATE_CST_OK_P, it is ok to
2224    return an aggregate constant.  */
2225 
2226 static tree
constant_value_1(tree decl,bool strict_p,bool return_aggregate_cst_ok_p)2227 constant_value_1 (tree decl, bool strict_p, bool return_aggregate_cst_ok_p)
2228 {
2229   while (TREE_CODE (decl) == CONST_DECL
2230 	 || decl_constant_var_p (decl)
2231 	 || (!strict_p && VAR_P (decl)
2232 	     && CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (decl))))
2233     {
2234       tree init;
2235       /* If DECL is a static data member in a template
2236 	 specialization, we must instantiate it here.  The
2237 	 initializer for the static data member is not processed
2238 	 until needed; we need it now.  */
2239       mark_used (decl, tf_none);
2240       init = DECL_INITIAL (decl);
2241       if (init == error_mark_node)
2242 	{
2243 	  if (TREE_CODE (decl) == CONST_DECL
2244 	      || DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
2245 	    /* Treat the error as a constant to avoid cascading errors on
2246 	       excessively recursive template instantiation (c++/9335).  */
2247 	    return init;
2248 	  else
2249 	    return decl;
2250 	}
2251       /* Initializers in templates are generally expanded during
2252 	 instantiation, so before that for const int i(2)
2253 	 INIT is a TREE_LIST with the actual initializer as
2254 	 TREE_VALUE.  */
2255       if (processing_template_decl
2256 	  && init
2257 	  && TREE_CODE (init) == TREE_LIST
2258 	  && TREE_CHAIN (init) == NULL_TREE)
2259 	init = TREE_VALUE (init);
2260       /* Instantiate a non-dependent initializer for user variables.  We
2261 	 mustn't do this for the temporary for an array compound literal;
2262 	 trying to instatiate the initializer will keep creating new
2263 	 temporaries until we crash.  Probably it's not useful to do it for
2264 	 other artificial variables, either.  */
2265       if (!DECL_ARTIFICIAL (decl))
2266 	init = instantiate_non_dependent_or_null (init);
2267       if (!init
2268 	  || !TREE_TYPE (init)
2269 	  || !TREE_CONSTANT (init)
2270 	  || (!return_aggregate_cst_ok_p
2271 	      /* Unless RETURN_AGGREGATE_CST_OK_P is true, do not
2272 		 return an aggregate constant (of which string
2273 		 literals are a special case), as we do not want
2274 		 to make inadvertent copies of such entities, and
2275 		 we must be sure that their addresses are the
2276  		 same everywhere.  */
2277 	      && (TREE_CODE (init) == CONSTRUCTOR
2278 		  || TREE_CODE (init) == STRING_CST)))
2279 	break;
2280       /* Don't return a CONSTRUCTOR for a variable with partial run-time
2281 	 initialization, since it doesn't represent the entire value.
2282 	 Similarly for VECTOR_CSTs created by cp_folding those
2283 	 CONSTRUCTORs.  */
2284       if ((TREE_CODE (init) == CONSTRUCTOR
2285 	   || TREE_CODE (init) == VECTOR_CST)
2286 	  && !DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl))
2287 	break;
2288       /* If the variable has a dynamic initializer, don't use its
2289 	 DECL_INITIAL which doesn't reflect the real value.  */
2290       if (VAR_P (decl)
2291 	  && TREE_STATIC (decl)
2292 	  && !DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P (decl)
2293 	  && DECL_NONTRIVIALLY_INITIALIZED_P (decl))
2294 	break;
2295       decl = unshare_expr (init);
2296     }
2297   return decl;
2298 }
2299 
2300 /* If DECL is a CONST_DECL, or a constant VAR_DECL initialized by constant
2301    of integral or enumeration type, or a constexpr variable of scalar type,
2302    then return that value.  These are those variables permitted in constant
2303    expressions by [5.19/1].  */
2304 
2305 tree
scalar_constant_value(tree decl)2306 scalar_constant_value (tree decl)
2307 {
2308   return constant_value_1 (decl, /*strict_p=*/true,
2309 			   /*return_aggregate_cst_ok_p=*/false);
2310 }
2311 
2312 /* Like scalar_constant_value, but can also return aggregate initializers.  */
2313 
2314 tree
decl_really_constant_value(tree decl)2315 decl_really_constant_value (tree decl)
2316 {
2317   return constant_value_1 (decl, /*strict_p=*/true,
2318 			   /*return_aggregate_cst_ok_p=*/true);
2319 }
2320 
2321 /* A more relaxed version of scalar_constant_value, used by the
2322    common C/C++ code.  */
2323 
2324 tree
decl_constant_value(tree decl)2325 decl_constant_value (tree decl)
2326 {
2327   return constant_value_1 (decl, /*strict_p=*/processing_template_decl,
2328 			   /*return_aggregate_cst_ok_p=*/true);
2329 }
2330 
2331 /* Common subroutines of build_new and build_vec_delete.  */
2332 
2333 /* Build and return a NEW_EXPR.  If NELTS is non-NULL, TYPE[NELTS] is
2334    the type of the object being allocated; otherwise, it's just TYPE.
2335    INIT is the initializer, if any.  USE_GLOBAL_NEW is true if the
2336    user explicitly wrote "::operator new".  PLACEMENT, if non-NULL, is
2337    a vector of arguments to be provided as arguments to a placement
2338    new operator.  This routine performs no semantic checks; it just
2339    creates and returns a NEW_EXPR.  */
2340 
2341 static tree
build_raw_new_expr(vec<tree,va_gc> * placement,tree type,tree nelts,vec<tree,va_gc> * init,int use_global_new)2342 build_raw_new_expr (vec<tree, va_gc> *placement, tree type, tree nelts,
2343 		    vec<tree, va_gc> *init, int use_global_new)
2344 {
2345   tree init_list;
2346   tree new_expr;
2347 
2348   /* If INIT is NULL, the we want to store NULL_TREE in the NEW_EXPR.
2349      If INIT is not NULL, then we want to store VOID_ZERO_NODE.  This
2350      permits us to distinguish the case of a missing initializer "new
2351      int" from an empty initializer "new int()".  */
2352   if (init == NULL)
2353     init_list = NULL_TREE;
2354   else if (init->is_empty ())
2355     init_list = void_node;
2356   else
2357     {
2358       init_list = build_tree_list_vec (init);
2359       for (tree v = init_list; v; v = TREE_CHAIN (v))
2360 	if (TREE_CODE (TREE_VALUE (v)) == OVERLOAD)
2361 	  lookup_keep (TREE_VALUE (v), true);
2362     }
2363 
2364   new_expr = build4 (NEW_EXPR, build_pointer_type (type),
2365 		     build_tree_list_vec (placement), type, nelts,
2366 		     init_list);
2367   NEW_EXPR_USE_GLOBAL (new_expr) = use_global_new;
2368   TREE_SIDE_EFFECTS (new_expr) = 1;
2369 
2370   return new_expr;
2371 }
2372 
2373 /* Diagnose uninitialized const members or reference members of type
2374    TYPE. USING_NEW is used to disambiguate the diagnostic between a
2375    new expression without a new-initializer and a declaration. Returns
2376    the error count. */
2377 
2378 static int
diagnose_uninitialized_cst_or_ref_member_1(tree type,tree origin,bool using_new,bool complain)2379 diagnose_uninitialized_cst_or_ref_member_1 (tree type, tree origin,
2380 					    bool using_new, bool complain)
2381 {
2382   tree field;
2383   int error_count = 0;
2384 
2385   if (type_has_user_provided_constructor (type))
2386     return 0;
2387 
2388   for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
2389     {
2390       tree field_type;
2391 
2392       if (TREE_CODE (field) != FIELD_DECL)
2393 	continue;
2394 
2395       field_type = strip_array_types (TREE_TYPE (field));
2396 
2397       if (type_has_user_provided_constructor (field_type))
2398 	continue;
2399 
2400       if (TREE_CODE (field_type) == REFERENCE_TYPE)
2401 	{
2402 	  ++ error_count;
2403 	  if (complain)
2404 	    {
2405 	      if (DECL_CONTEXT (field) == origin)
2406 		{
2407 		  if (using_new)
2408 		    error ("uninitialized reference member in %q#T "
2409 			   "using %<new%> without new-initializer", origin);
2410 		  else
2411 		    error ("uninitialized reference member in %q#T", origin);
2412 		}
2413 	      else
2414 		{
2415 		  if (using_new)
2416 		    error ("uninitialized reference member in base %q#T "
2417 			   "of %q#T using %<new%> without new-initializer",
2418 			   DECL_CONTEXT (field), origin);
2419 		  else
2420 		    error ("uninitialized reference member in base %q#T "
2421 			   "of %q#T", DECL_CONTEXT (field), origin);
2422 		}
2423 	      inform (DECL_SOURCE_LOCATION (field),
2424 		      "%q#D should be initialized", field);
2425 	    }
2426 	}
2427 
2428       if (CP_TYPE_CONST_P (field_type))
2429 	{
2430 	  ++ error_count;
2431 	  if (complain)
2432 	    {
2433 	      if (DECL_CONTEXT (field) == origin)
2434 		{
2435 		  if (using_new)
2436 		    error ("uninitialized const member in %q#T "
2437 			   "using %<new%> without new-initializer", origin);
2438 		  else
2439 		    error ("uninitialized const member in %q#T", origin);
2440 		}
2441 	      else
2442 		{
2443 		  if (using_new)
2444 		    error ("uninitialized const member in base %q#T "
2445 			   "of %q#T using %<new%> without new-initializer",
2446 			   DECL_CONTEXT (field), origin);
2447 		  else
2448 		    error ("uninitialized const member in base %q#T "
2449 			   "of %q#T", DECL_CONTEXT (field), origin);
2450 		}
2451 	      inform (DECL_SOURCE_LOCATION (field),
2452 		      "%q#D should be initialized", field);
2453 	    }
2454 	}
2455 
2456       if (CLASS_TYPE_P (field_type))
2457 	error_count
2458 	  += diagnose_uninitialized_cst_or_ref_member_1 (field_type, origin,
2459 							 using_new, complain);
2460     }
2461   return error_count;
2462 }
2463 
2464 int
diagnose_uninitialized_cst_or_ref_member(tree type,bool using_new,bool complain)2465 diagnose_uninitialized_cst_or_ref_member (tree type, bool using_new, bool complain)
2466 {
2467   return diagnose_uninitialized_cst_or_ref_member_1 (type, type, using_new, complain);
2468 }
2469 
2470 /* Call __cxa_bad_array_new_length to indicate that the size calculation
2471    overflowed.  Pretend it returns sizetype so that it plays nicely in the
2472    COND_EXPR.  */
2473 
2474 tree
throw_bad_array_new_length(void)2475 throw_bad_array_new_length (void)
2476 {
2477   if (!fn)
2478     {
2479       tree name = get_identifier ("__cxa_throw_bad_array_new_length");
2480 
2481       fn = get_global_binding (name);
2482       if (!fn)
2483 	fn = push_throw_library_fn
2484 	  (name, build_function_type_list (sizetype, NULL_TREE));
2485     }
2486 
2487   return build_cxx_call (fn, 0, NULL, tf_warning_or_error);
2488 }
2489 
2490 /* Attempt to find the initializer for flexible array field T in the
2491    initializer INIT, when non-null.  Returns the initializer when
2492    successful and NULL otherwise.  */
2493 static tree
find_flexarray_init(tree t,tree init)2494 find_flexarray_init (tree t, tree init)
2495 {
2496   if (!init || init == error_mark_node)
2497     return NULL_TREE;
2498 
2499   unsigned HOST_WIDE_INT idx;
2500   tree field, elt;
2501 
2502   /* Iterate over all top-level initializer elements.  */
2503   FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init), idx, field, elt)
2504     /* If the member T is found, return it.  */
2505     if (field == t)
2506       return elt;
2507 
2508   return NULL_TREE;
2509 }
2510 
2511 /* Attempt to verify that the argument, OPER, of a placement new expression
2512    refers to an object sufficiently large for an object of TYPE or an array
2513    of NELTS of such objects when NELTS is non-null, and issue a warning when
2514    it does not.  SIZE specifies the size needed to construct the object or
2515    array and captures the result of NELTS * sizeof (TYPE). (SIZE could be
2516    greater when the array under construction requires a cookie to store
2517    NELTS.  GCC's placement new expression stores the cookie when invoking
2518    a user-defined placement new operator function but not the default one.
2519    Placement new expressions with user-defined placement new operator are
2520    not diagnosed since we don't know how they use the buffer (this could
2521    be a future extension).  */
2522 static void
warn_placement_new_too_small(tree type,tree nelts,tree size,tree oper)2523 warn_placement_new_too_small (tree type, tree nelts, tree size, tree oper)
2524 {
2525   location_t loc = EXPR_LOC_OR_LOC (oper, input_location);
2526 
2527   /* The number of bytes to add to or subtract from the size of the provided
2528      buffer based on an offset into an array or an array element reference.
2529      Although intermediate results may be negative (as in a[3] - 2) a valid
2530      final result cannot be.  */
2531   offset_int adjust = 0;
2532   /* True when the size of the entire destination object should be used
2533      to compute the possibly optimistic estimate of the available space.  */
2534   bool use_obj_size = false;
2535   /* True when the reference to the destination buffer is an ADDR_EXPR.  */
2536   bool addr_expr = false;
2537 
2538   STRIP_NOPS (oper);
2539 
2540   /* Using a function argument or a (non-array) variable as an argument
2541      to placement new is not checked since it's unknown what it might
2542      point to.  */
2543   if (TREE_CODE (oper) == PARM_DECL
2544       || VAR_P (oper)
2545       || TREE_CODE (oper) == COMPONENT_REF)
2546     return;
2547 
2548   /* Evaluate any constant expressions.  */
2549   size = fold_non_dependent_expr (size);
2550 
2551   /* Handle the common case of array + offset expression when the offset
2552      is a constant.  */
2553   if (TREE_CODE (oper) == POINTER_PLUS_EXPR)
2554     {
2555       /* If the offset is compile-time constant, use it to compute a more
2556 	 accurate estimate of the size of the buffer.  Since the operand
2557 	 of POINTER_PLUS_EXPR is represented as an unsigned type, convert
2558 	 it to signed first.
2559 	 Otherwise, use the size of the entire array as an optimistic
2560 	 estimate (this may lead to false negatives).  */
2561       tree adj = TREE_OPERAND (oper, 1);
2562       if (CONSTANT_CLASS_P (adj))
2563 	adjust += wi::to_offset (convert (ssizetype, adj));
2564       else
2565 	use_obj_size = true;
2566 
2567       oper = TREE_OPERAND (oper, 0);
2568 
2569       STRIP_NOPS (oper);
2570     }
2571 
2572   if (TREE_CODE (oper) == TARGET_EXPR)
2573     oper = TREE_OPERAND (oper, 1);
2574   else if (TREE_CODE (oper) == ADDR_EXPR)
2575     {
2576       addr_expr = true;
2577       oper = TREE_OPERAND (oper, 0);
2578     }
2579 
2580   STRIP_NOPS (oper);
2581 
2582   if (TREE_CODE (oper) == ARRAY_REF
2583       && (addr_expr || TREE_CODE (TREE_TYPE (oper)) == ARRAY_TYPE))
2584     {
2585       /* Similar to the offset computed above, see if the array index
2586 	 is a compile-time constant.  If so, and unless the offset was
2587 	 not a compile-time constant, use the index to determine the
2588 	 size of the buffer.  Otherwise, use the entire array as
2589 	 an optimistic estimate of the size.  */
2590       const_tree adj = fold_non_dependent_expr (TREE_OPERAND (oper, 1));
2591       if (!use_obj_size && CONSTANT_CLASS_P (adj))
2592 	adjust += wi::to_offset (adj);
2593       else
2594 	{
2595 	  use_obj_size = true;
2596 	  adjust = 0;
2597 	}
2598 
2599       oper = TREE_OPERAND (oper, 0);
2600     }
2601 
2602   /* Refers to the declared object that constains the subobject referenced
2603      by OPER.  When the object is initialized, makes it possible to determine
2604      the actual size of a flexible array member used as the buffer passed
2605      as OPER to placement new.  */
2606   tree var_decl = NULL_TREE;
2607   /* True when operand is a COMPONENT_REF, to distinguish flexible array
2608      members from arrays of unspecified size.  */
2609   bool compref = TREE_CODE (oper) == COMPONENT_REF;
2610 
2611   /* For COMPONENT_REF (i.e., a struct member) the size of the entire
2612      enclosing struct.  Used to validate the adjustment (offset) into
2613      an array at the end of a struct.  */
2614   offset_int compsize = 0;
2615 
2616   /* Descend into a struct or union to find the member whose address
2617      is being used as the argument.  */
2618   if (TREE_CODE (oper) == COMPONENT_REF)
2619     {
2620       tree comptype = TREE_TYPE (TREE_OPERAND (oper, 0));
2621       compsize = wi::to_offset (TYPE_SIZE_UNIT (comptype));
2622 
2623       tree op0 = oper;
2624       while (TREE_CODE (op0 = TREE_OPERAND (op0, 0)) == COMPONENT_REF);
2625       if (VAR_P (op0))
2626 	var_decl = op0;
2627       oper = TREE_OPERAND (oper, 1);
2628     }
2629 
2630   tree opertype = TREE_TYPE (oper);
2631   if ((addr_expr || !POINTER_TYPE_P (opertype))
2632       && (VAR_P (oper)
2633 	  || TREE_CODE (oper) == FIELD_DECL
2634 	  || TREE_CODE (oper) == PARM_DECL))
2635     {
2636       /* A possibly optimistic estimate of the number of bytes available
2637 	 in the destination buffer.  */
2638       offset_int bytes_avail = 0;
2639       /* True when the estimate above is in fact the exact size
2640 	 of the destination buffer rather than an estimate.  */
2641       bool exact_size = true;
2642 
2643       /* Treat members of unions and members of structs uniformly, even
2644 	 though the size of a member of a union may be viewed as extending
2645 	 to the end of the union itself (it is by __builtin_object_size).  */
2646       if ((VAR_P (oper) || use_obj_size)
2647 	  && DECL_SIZE_UNIT (oper)
2648 	  && tree_fits_uhwi_p (DECL_SIZE_UNIT (oper)))
2649 	{
2650 	  /* Use the size of the entire array object when the expression
2651 	     refers to a variable or its size depends on an expression
2652 	     that's not a compile-time constant.  */
2653 	  bytes_avail = wi::to_offset (DECL_SIZE_UNIT (oper));
2654 	  exact_size = !use_obj_size;
2655 	}
2656       else if (tree opersize = TYPE_SIZE_UNIT (opertype))
2657 	{
2658 	  /* Use the size of the type of the destination buffer object
2659 	     as the optimistic estimate of the available space in it.
2660 	     Use the maximum possible size for zero-size arrays and
2661 	     flexible array members (except of initialized objects
2662 	     thereof).  */
2663 	  if (TREE_CODE (opersize) == INTEGER_CST)
2664 	    bytes_avail = wi::to_offset (opersize);
2665 	}
2666 
2667       if (bytes_avail == 0)
2668 	{
2669 	  if (var_decl)
2670 	    {
2671 	      /* Constructing into a buffer provided by the flexible array
2672 		 member of a declared object (which is permitted as a G++
2673 		 extension).  If the array member has been initialized,
2674 		 determine its size from the initializer.  Otherwise,
2675 		 the array size is zero.  */
2676 	      if (tree init = find_flexarray_init (oper,
2677 						   DECL_INITIAL (var_decl)))
2678 		bytes_avail = wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (init)));
2679 	    }
2680 	  else
2681 	    bytes_avail = (wi::to_offset (TYPE_MAX_VALUE (ptrdiff_type_node))
2682 			   - compsize);
2683 	}
2684 
2685       tree_code oper_code = TREE_CODE (opertype);
2686 
2687       if (compref && oper_code == ARRAY_TYPE)
2688 	{
2689 	  tree nelts = array_type_nelts_top (opertype);
2690 	  tree nelts_cst = maybe_constant_value (nelts);
2691 	  if (TREE_CODE (nelts_cst) == INTEGER_CST
2692 	      && integer_onep (nelts_cst)
2693 	      && !var_decl
2694 	      && warn_placement_new < 2)
2695 	    return;
2696 	}
2697 
2698       /* Reduce the size of the buffer by the adjustment computed above
2699 	 from the offset and/or the index into the array.  */
2700       if (bytes_avail < adjust || adjust < 0)
2701 	bytes_avail = 0;
2702       else
2703 	{
2704 	  tree elttype = (TREE_CODE (opertype) == ARRAY_TYPE
2705 			  ? TREE_TYPE (opertype) : opertype);
2706 	  if (tree eltsize = TYPE_SIZE_UNIT (elttype))
2707 	    {
2708 	      bytes_avail -= adjust * wi::to_offset (eltsize);
2709 	      if (bytes_avail < 0)
2710 		bytes_avail = 0;
2711 	    }
2712 	}
2713 
2714       /* The minimum amount of space needed for the allocation.  This
2715 	 is an optimistic estimate that makes it possible to detect
2716 	 placement new invocation for some undersize buffers but not
2717 	 others.  */
2718       offset_int bytes_need;
2719 
2720       if (CONSTANT_CLASS_P (size))
2721 	bytes_need = wi::to_offset (size);
2722       else if (nelts && CONSTANT_CLASS_P (nelts))
2723 	bytes_need = (wi::to_offset (nelts)
2724 		      * wi::to_offset (TYPE_SIZE_UNIT (type)));
2725       else if (tree_fits_uhwi_p (TYPE_SIZE_UNIT (type)))
2726 	bytes_need = wi::to_offset (TYPE_SIZE_UNIT (type));
2727       else
2728 	{
2729 	  /* The type is a VLA.  */
2730 	  return;
2731 	}
2732 
2733       if (bytes_avail < bytes_need)
2734 	{
2735 	  if (nelts)
2736 	    if (CONSTANT_CLASS_P (nelts))
2737 	      warning_at (loc, OPT_Wplacement_new_,
2738 			  exact_size ?
2739 			  "placement new constructing an object of type "
2740 			  "%<%T [%wu]%> and size %qwu in a region of type %qT "
2741 			  "and size %qwi"
2742 			  : "placement new constructing an object of type "
2743 			  "%<%T [%wu]%> and size %qwu in a region of type %qT "
2744 			  "and size at most %qwu",
2745 			  type, tree_to_uhwi (nelts), bytes_need.to_uhwi (),
2746 			  opertype, bytes_avail.to_uhwi ());
2747 	    else
2748 	      warning_at (loc, OPT_Wplacement_new_,
2749 			  exact_size ?
2750 			  "placement new constructing an array of objects "
2751 			  "of type %qT and size %qwu in a region of type %qT "
2752 			  "and size %qwi"
2753 			  : "placement new constructing an array of objects "
2754 			  "of type %qT and size %qwu in a region of type %qT "
2755 			  "and size at most %qwu",
2756 			  type, bytes_need.to_uhwi (), opertype,
2757 			  bytes_avail.to_uhwi ());
2758 	  else
2759 	    warning_at (loc, OPT_Wplacement_new_,
2760 			exact_size ?
2761 			"placement new constructing an object of type %qT "
2762 			"and size %qwu in a region of type %qT and size %qwi"
2763 			: "placement new constructing an object of type %qT "
2764 			"and size %qwu in a region of type %qT and size "
2765 			"at most %qwu",
2766 			type, bytes_need.to_uhwi (), opertype,
2767 			bytes_avail.to_uhwi ());
2768 	}
2769     }
2770 }
2771 
2772 /* True if alignof(T) > __STDCPP_DEFAULT_NEW_ALIGNMENT__.  */
2773 
2774 bool
type_has_new_extended_alignment(tree t)2775 type_has_new_extended_alignment (tree t)
2776 {
2777   return (aligned_new_threshold
2778 	  && TYPE_ALIGN_UNIT (t) > (unsigned)aligned_new_threshold);
2779 }
2780 
2781 /* Return the alignment we expect malloc to guarantee.  This should just be
2782    MALLOC_ABI_ALIGNMENT, but that macro defaults to only BITS_PER_WORD for some
2783    reason, so don't let the threshold be smaller than max_align_t_align.  */
2784 
2785 unsigned
malloc_alignment()2786 malloc_alignment ()
2787 {
2788   return MAX (max_align_t_align(), MALLOC_ABI_ALIGNMENT);
2789 }
2790 
2791 /* Determine whether an allocation function is a namespace-scope
2792    non-replaceable placement new function. See DR 1748.
2793    TODO: Enable in all standard modes.  */
2794 static bool
std_placement_new_fn_p(tree alloc_fn)2795 std_placement_new_fn_p (tree alloc_fn)
2796 {
2797   if (DECL_NAMESPACE_SCOPE_P (alloc_fn))
2798     {
2799       tree first_arg = TREE_CHAIN (TYPE_ARG_TYPES (TREE_TYPE (alloc_fn)));
2800       if ((TREE_VALUE (first_arg) == ptr_type_node)
2801 	  && TREE_CHAIN (first_arg) == void_list_node)
2802 	return true;
2803     }
2804   return false;
2805 }
2806 
2807 /* Generate code for a new-expression, including calling the "operator
2808    new" function, initializing the object, and, if an exception occurs
2809    during construction, cleaning up.  The arguments are as for
2810    build_raw_new_expr.  This may change PLACEMENT and INIT.
2811    TYPE is the type of the object being constructed, possibly an array
2812    of NELTS elements when NELTS is non-null (in "new T[NELTS]", T may
2813    be an array of the form U[inner], with the whole expression being
2814    "new U[NELTS][inner]").  */
2815 
2816 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)2817 build_new_1 (vec<tree, va_gc> **placement, tree type, tree nelts,
2818 	     vec<tree, va_gc> **init, bool globally_qualified_p,
2819 	     tsubst_flags_t complain)
2820 {
2821   tree size, rval;
2822   /* True iff this is a call to "operator new[]" instead of just
2823      "operator new".  */
2824   bool array_p = false;
2825   /* If ARRAY_P is true, the element type of the array.  This is never
2826      an ARRAY_TYPE; for something like "new int[3][4]", the
2827      ELT_TYPE is "int".  If ARRAY_P is false, this is the same type as
2828      TYPE.  */
2829   tree elt_type;
2830   /* The type of the new-expression.  (This type is always a pointer
2831      type.)  */
2832   tree pointer_type;
2833   tree non_const_pointer_type;
2834   /* The most significant array bound in int[OUTER_NELTS][inner].  */
2835   tree outer_nelts = NULL_TREE;
2836   /* For arrays with a non-constant number of elements, a bounds checks
2837      on the NELTS parameter to avoid integer overflow at runtime. */
2838   tree outer_nelts_check = NULL_TREE;
2839   bool outer_nelts_from_type = false;
2840   /* Number of the "inner" elements in "new T[OUTER_NELTS][inner]".  */
2841   offset_int inner_nelts_count = 1;
2842   tree alloc_call, alloc_expr;
2843   /* Size of the inner array elements (those with constant dimensions). */
2844   offset_int inner_size;
2845   /* The address returned by the call to "operator new".  This node is
2846      a VAR_DECL and is therefore reusable.  */
2847   tree alloc_node;
2848   tree alloc_fn;
2849   tree cookie_expr, init_expr;
2850   int nothrow, check_new;
2851   /* If non-NULL, the number of extra bytes to allocate at the
2852      beginning of the storage allocated for an array-new expression in
2853      order to store the number of elements.  */
2854   tree cookie_size = NULL_TREE;
2855   tree placement_first;
2856   tree placement_expr = NULL_TREE;
2857   /* True if the function we are calling is a placement allocation
2858      function.  */
2859   bool placement_allocation_fn_p;
2860   /* True if the storage must be initialized, either by a constructor
2861      or due to an explicit new-initializer.  */
2862   bool is_initialized;
2863   /* The address of the thing allocated, not including any cookie.  In
2864      particular, if an array cookie is in use, DATA_ADDR is the
2865      address of the first array element.  This node is a VAR_DECL, and
2866      is therefore reusable.  */
2867   tree data_addr;
2868   tree init_preeval_expr = NULL_TREE;
2869   tree orig_type = type;
2870 
2871   if (nelts)
2872     {
2873       outer_nelts = nelts;
2874       array_p = true;
2875     }
2876   else if (TREE_CODE (type) == ARRAY_TYPE)
2877     {
2878       /* Transforms new (T[N]) to new T[N].  The former is a GNU
2879 	 extension for variable N.  (This also covers new T where T is
2880 	 a VLA typedef.)  */
2881       array_p = true;
2882       nelts = array_type_nelts_top (type);
2883       outer_nelts = nelts;
2884       type = TREE_TYPE (type);
2885       outer_nelts_from_type = true;
2886     }
2887 
2888   /* Lots of logic below depends on whether we have a constant number of
2889      elements, so go ahead and fold it now.  */
2890   const_tree cst_outer_nelts = fold_non_dependent_expr (outer_nelts);
2891 
2892   /* If our base type is an array, then make sure we know how many elements
2893      it has.  */
2894   for (elt_type = type;
2895        TREE_CODE (elt_type) == ARRAY_TYPE;
2896        elt_type = TREE_TYPE (elt_type))
2897     {
2898       tree inner_nelts = array_type_nelts_top (elt_type);
2899       tree inner_nelts_cst = maybe_constant_value (inner_nelts);
2900       if (TREE_CODE (inner_nelts_cst) == INTEGER_CST)
2901 	{
2902 	  bool overflow;
2903 	  offset_int result = wi::mul (wi::to_offset (inner_nelts_cst),
2904 				       inner_nelts_count, SIGNED, &overflow);
2905 	  if (overflow)
2906 	    {
2907 	      if (complain & tf_error)
2908 		error ("integer overflow in array size");
2909 	      nelts = error_mark_node;
2910 	    }
2911 	  inner_nelts_count = result;
2912 	}
2913       else
2914 	{
2915 	  if (complain & tf_error)
2916 	    {
2917 	      error_at (EXPR_LOC_OR_LOC (inner_nelts, input_location),
2918 			"array size in new-expression must be constant");
2919 	      cxx_constant_value(inner_nelts);
2920 	    }
2921 	  nelts = error_mark_node;
2922 	}
2923       if (nelts != error_mark_node)
2924 	nelts = cp_build_binary_op (input_location,
2925 				    MULT_EXPR, nelts,
2926 				    inner_nelts_cst,
2927 				    complain);
2928     }
2929 
2930   if (variably_modified_type_p (elt_type, NULL_TREE) && (complain & tf_error))
2931     {
2932       error ("variably modified type not allowed in new-expression");
2933       return error_mark_node;
2934     }
2935 
2936   if (nelts == error_mark_node)
2937     return error_mark_node;
2938 
2939   /* Warn if we performed the (T[N]) to T[N] transformation and N is
2940      variable.  */
2941   if (outer_nelts_from_type
2942       && !TREE_CONSTANT (cst_outer_nelts))
2943     {
2944       if (complain & tf_warning_or_error)
2945 	{
2946 	  pedwarn (EXPR_LOC_OR_LOC (outer_nelts, input_location), OPT_Wvla,
2947 		   typedef_variant_p (orig_type)
2948 		   ? G_("non-constant array new length must be specified "
2949 			"directly, not by typedef")
2950 		   : G_("non-constant array new length must be specified "
2951 			"without parentheses around the type-id"));
2952 	}
2953       else
2954 	return error_mark_node;
2955     }
2956 
2957   if (VOID_TYPE_P (elt_type))
2958     {
2959       if (complain & tf_error)
2960         error ("invalid type %<void%> for new");
2961       return error_mark_node;
2962     }
2963 
2964   if (abstract_virtuals_error_sfinae (ACU_NEW, elt_type, complain))
2965     return error_mark_node;
2966 
2967   is_initialized = (type_build_ctor_call (elt_type) || *init != NULL);
2968 
2969   if (*init == NULL && cxx_dialect < cxx11)
2970     {
2971       bool maybe_uninitialized_error = false;
2972       /* A program that calls for default-initialization [...] of an
2973 	 entity of reference type is ill-formed. */
2974       if (CLASSTYPE_REF_FIELDS_NEED_INIT (elt_type))
2975 	maybe_uninitialized_error = true;
2976 
2977       /* A new-expression that creates an object of type T initializes
2978 	 that object as follows:
2979       - If the new-initializer is omitted:
2980         -- If T is a (possibly cv-qualified) non-POD class type
2981 	   (or array thereof), the object is default-initialized (8.5).
2982 	   [...]
2983         -- Otherwise, the object created has indeterminate
2984 	   value. If T is a const-qualified type, or a (possibly
2985 	   cv-qualified) POD class type (or array thereof)
2986 	   containing (directly or indirectly) a member of
2987 	   const-qualified type, the program is ill-formed; */
2988 
2989       if (CLASSTYPE_READONLY_FIELDS_NEED_INIT (elt_type))
2990 	maybe_uninitialized_error = true;
2991 
2992       if (maybe_uninitialized_error
2993 	  && diagnose_uninitialized_cst_or_ref_member (elt_type,
2994 						       /*using_new=*/true,
2995 						       complain & tf_error))
2996 	return error_mark_node;
2997     }
2998 
2999   if (CP_TYPE_CONST_P (elt_type) && *init == NULL
3000       && default_init_uninitialized_part (elt_type))
3001     {
3002       if (complain & tf_error)
3003         error ("uninitialized const in %<new%> of %q#T", elt_type);
3004       return error_mark_node;
3005     }
3006 
3007   size = size_in_bytes (elt_type);
3008   if (array_p)
3009     {
3010       /* Maximum available size in bytes.  Half of the address space
3011 	 minus the cookie size.  */
3012       offset_int max_size
3013 	= wi::set_bit_in_zero <offset_int> (TYPE_PRECISION (sizetype) - 1);
3014       /* Maximum number of outer elements which can be allocated. */
3015       offset_int max_outer_nelts;
3016       tree max_outer_nelts_tree;
3017 
3018       gcc_assert (TREE_CODE (size) == INTEGER_CST);
3019       cookie_size = targetm.cxx.get_cookie_size (elt_type);
3020       gcc_assert (TREE_CODE (cookie_size) == INTEGER_CST);
3021       gcc_checking_assert (wi::ltu_p (wi::to_offset (cookie_size), max_size));
3022       /* Unconditionally subtract the cookie size.  This decreases the
3023 	 maximum object size and is safe even if we choose not to use
3024 	 a cookie after all.  */
3025       max_size -= wi::to_offset (cookie_size);
3026       bool overflow;
3027       inner_size = wi::mul (wi::to_offset (size), inner_nelts_count, SIGNED,
3028 			    &overflow);
3029       if (overflow || wi::gtu_p (inner_size, max_size))
3030 	{
3031 	  if (complain & tf_error)
3032 	    error ("size of array is too large");
3033 	  return error_mark_node;
3034 	}
3035 
3036       max_outer_nelts = wi::udiv_trunc (max_size, inner_size);
3037       max_outer_nelts_tree = wide_int_to_tree (sizetype, max_outer_nelts);
3038 
3039       size = size_binop (MULT_EXPR, size, fold_convert (sizetype, nelts));
3040 
3041       if (TREE_CODE (cst_outer_nelts) == INTEGER_CST)
3042 	{
3043 	  if (tree_int_cst_lt (max_outer_nelts_tree, cst_outer_nelts))
3044 	    {
3045 	      /* When the array size is constant, check it at compile time
3046 		 to make sure it doesn't exceed the implementation-defined
3047 		 maximum, as required by C++ 14 (in C++ 11 this requirement
3048 		 isn't explicitly stated but it's enforced anyway -- see
3049 		 grokdeclarator in cp/decl.c).  */
3050 	      if (complain & tf_error)
3051 		error ("size of array is too large");
3052 	      return error_mark_node;
3053 	    }
3054 	}
3055       else
3056  	{
3057 	  /* When a runtime check is necessary because the array size
3058 	     isn't constant, keep only the top-most seven bits (starting
3059 	     with the most significant non-zero bit) of the maximum size
3060 	     to compare the array size against, to simplify encoding the
3061 	     constant maximum size in the instruction stream.  */
3062 
3063 	  unsigned shift = (max_outer_nelts.get_precision ()) - 7
3064 	    - wi::clz (max_outer_nelts);
3065 	  max_outer_nelts = (max_outer_nelts >> shift) << shift;
3066 
3067           outer_nelts_check = fold_build2 (LE_EXPR, boolean_type_node,
3068 					   outer_nelts,
3069 					   max_outer_nelts_tree);
3070 	}
3071     }
3072 
3073   tree align_arg = NULL_TREE;
3074   if (type_has_new_extended_alignment (elt_type))
3075     align_arg = build_int_cst (align_type_node, TYPE_ALIGN_UNIT (elt_type));
3076 
3077   alloc_fn = NULL_TREE;
3078 
3079   /* If PLACEMENT is a single simple pointer type not passed by
3080      reference, prepare to capture it in a temporary variable.  Do
3081      this now, since PLACEMENT will change in the calls below.  */
3082   placement_first = NULL_TREE;
3083   if (vec_safe_length (*placement) == 1
3084       && (TYPE_PTR_P (TREE_TYPE ((**placement)[0]))))
3085     placement_first = (**placement)[0];
3086 
3087   bool member_new_p = false;
3088 
3089   /* Allocate the object.  */
3090   tree fnname;
3091   tree fns;
3092 
3093   fnname = ovl_op_identifier (false, array_p ? VEC_NEW_EXPR : NEW_EXPR);
3094 
3095   member_new_p = !globally_qualified_p
3096 		 && CLASS_TYPE_P (elt_type)
3097 		 && (array_p
3098 		     ? TYPE_HAS_ARRAY_NEW_OPERATOR (elt_type)
3099 		     : TYPE_HAS_NEW_OPERATOR (elt_type));
3100 
3101   if (member_new_p)
3102     {
3103       /* Use a class-specific operator new.  */
3104       /* If a cookie is required, add some extra space.  */
3105       if (array_p && TYPE_VEC_NEW_USES_COOKIE (elt_type))
3106 	size = size_binop (PLUS_EXPR, size, cookie_size);
3107       else
3108 	{
3109 	  cookie_size = NULL_TREE;
3110 	  /* No size arithmetic necessary, so the size check is
3111 	     not needed. */
3112 	  if (outer_nelts_check != NULL && inner_size == 1)
3113 	    outer_nelts_check = NULL_TREE;
3114 	}
3115       /* Perform the overflow check.  */
3116       tree errval = TYPE_MAX_VALUE (sizetype);
3117       if (cxx_dialect >= cxx11 && flag_exceptions)
3118 	errval = throw_bad_array_new_length ();
3119       if (outer_nelts_check != NULL_TREE)
3120 	size = fold_build3 (COND_EXPR, sizetype, outer_nelts_check,
3121 			    size, errval);
3122       /* Create the argument list.  */
3123       vec_safe_insert (*placement, 0, size);
3124       /* Do name-lookup to find the appropriate operator.  */
3125       fns = lookup_fnfields (elt_type, fnname, /*protect=*/2);
3126       if (fns == NULL_TREE)
3127 	{
3128 	  if (complain & tf_error)
3129 	    error ("no suitable %qD found in class %qT", fnname, elt_type);
3130 	  return error_mark_node;
3131 	}
3132       if (TREE_CODE (fns) == TREE_LIST)
3133 	{
3134 	  if (complain & tf_error)
3135 	    {
3136 	      error ("request for member %qD is ambiguous", fnname);
3137 	      print_candidates (fns);
3138 	    }
3139 	  return error_mark_node;
3140 	}
3141       tree dummy = build_dummy_object (elt_type);
3142       alloc_call = NULL_TREE;
3143       if (align_arg)
3144 	{
3145 	  vec<tree, va_gc> *align_args
3146 	    = vec_copy_and_insert (*placement, align_arg, 1);
3147 	  alloc_call
3148 	    = build_new_method_call (dummy, fns, &align_args,
3149 				     /*conversion_path=*/NULL_TREE,
3150 				     LOOKUP_NORMAL, &alloc_fn, tf_none);
3151 	  /* If no matching function is found and the allocated object type
3152 	     has new-extended alignment, the alignment argument is removed
3153 	     from the argument list, and overload resolution is performed
3154 	     again.  */
3155 	  if (alloc_call == error_mark_node)
3156 	    alloc_call = NULL_TREE;
3157 	}
3158       if (!alloc_call)
3159 	alloc_call = build_new_method_call (dummy, fns, placement,
3160 					    /*conversion_path=*/NULL_TREE,
3161 					    LOOKUP_NORMAL,
3162 					    &alloc_fn, complain);
3163     }
3164   else
3165     {
3166       /* Use a global operator new.  */
3167       /* See if a cookie might be required.  */
3168       if (!(array_p && TYPE_VEC_NEW_USES_COOKIE (elt_type)))
3169 	{
3170 	  cookie_size = NULL_TREE;
3171 	  /* No size arithmetic necessary, so the size check is
3172 	     not needed. */
3173 	  if (outer_nelts_check != NULL && inner_size == 1)
3174 	    outer_nelts_check = NULL_TREE;
3175 	}
3176 
3177       alloc_call = build_operator_new_call (fnname, placement,
3178 					    &size, &cookie_size,
3179 					    align_arg, outer_nelts_check,
3180 					    &alloc_fn, complain);
3181     }
3182 
3183   if (alloc_call == error_mark_node)
3184     return error_mark_node;
3185 
3186   gcc_assert (alloc_fn != NULL_TREE);
3187 
3188   /* Now, check to see if this function is actually a placement
3189      allocation function.  This can happen even when PLACEMENT is NULL
3190      because we might have something like:
3191 
3192        struct S { void* operator new (size_t, int i = 0); };
3193 
3194      A call to `new S' will get this allocation function, even though
3195      there is no explicit placement argument.  If there is more than
3196      one argument, or there are variable arguments, then this is a
3197      placement allocation function.  */
3198   placement_allocation_fn_p
3199     = (type_num_arguments (TREE_TYPE (alloc_fn)) > 1
3200        || varargs_function_p (alloc_fn));
3201 
3202   if (warn_aligned_new
3203       && !placement_allocation_fn_p
3204       && TYPE_ALIGN (elt_type) > malloc_alignment ()
3205       && (warn_aligned_new > 1
3206 	  || CP_DECL_CONTEXT (alloc_fn) == global_namespace)
3207       && !aligned_allocation_fn_p (alloc_fn))
3208     {
3209       if (warning (OPT_Waligned_new_, "%<new%> of type %qT with extended "
3210 		   "alignment %d", elt_type, TYPE_ALIGN_UNIT (elt_type)))
3211 	{
3212 	  inform (input_location, "uses %qD, which does not have an alignment "
3213 		  "parameter", alloc_fn);
3214 	  if (!aligned_new_threshold)
3215 	    inform (input_location, "use %<-faligned-new%> to enable C++17 "
3216 				    "over-aligned new support");
3217 	}
3218     }
3219 
3220   /* If we found a simple case of PLACEMENT_EXPR above, then copy it
3221      into a temporary variable.  */
3222   if (!processing_template_decl
3223       && TREE_CODE (alloc_call) == CALL_EXPR
3224       && call_expr_nargs (alloc_call) == 2
3225       && TREE_CODE (TREE_TYPE (CALL_EXPR_ARG (alloc_call, 0))) == INTEGER_TYPE
3226       && TYPE_PTR_P (TREE_TYPE (CALL_EXPR_ARG (alloc_call, 1))))
3227     {
3228       tree placement = CALL_EXPR_ARG (alloc_call, 1);
3229 
3230       if (placement_first != NULL_TREE
3231 	  && (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (TREE_TYPE (placement)))
3232 	      || VOID_TYPE_P (TREE_TYPE (TREE_TYPE (placement)))))
3233 	{
3234 	  placement_expr = get_target_expr (placement_first);
3235 	  CALL_EXPR_ARG (alloc_call, 1)
3236 	    = fold_convert (TREE_TYPE (placement), placement_expr);
3237 	}
3238 
3239       if (!member_new_p
3240 	  && VOID_TYPE_P (TREE_TYPE (TREE_TYPE (CALL_EXPR_ARG (alloc_call, 1)))))
3241 	{
3242 	  /* Attempt to make the warning point at the operator new argument.  */
3243 	  if (placement_first)
3244 	    placement = placement_first;
3245 
3246 	  warn_placement_new_too_small (orig_type, nelts, size, placement);
3247 	}
3248     }
3249 
3250   /* In the simple case, we can stop now.  */
3251   pointer_type = build_pointer_type (type);
3252   if (!cookie_size && !is_initialized)
3253     return build_nop (pointer_type, alloc_call);
3254 
3255   /* Store the result of the allocation call in a variable so that we can
3256      use it more than once.  */
3257   alloc_expr = get_target_expr (alloc_call);
3258   alloc_node = TARGET_EXPR_SLOT (alloc_expr);
3259 
3260   /* Strip any COMPOUND_EXPRs from ALLOC_CALL.  */
3261   while (TREE_CODE (alloc_call) == COMPOUND_EXPR)
3262     alloc_call = TREE_OPERAND (alloc_call, 1);
3263 
3264   /* Preevaluate the placement args so that we don't reevaluate them for a
3265      placement delete.  */
3266   if (placement_allocation_fn_p)
3267     {
3268       tree inits;
3269       stabilize_call (alloc_call, &inits);
3270       if (inits)
3271 	alloc_expr = build2 (COMPOUND_EXPR, TREE_TYPE (alloc_expr), inits,
3272 			     alloc_expr);
3273     }
3274 
3275   /*        unless an allocation function is declared with an empty  excep-
3276      tion-specification  (_except.spec_),  throw(), it indicates failure to
3277      allocate storage by throwing a bad_alloc exception  (clause  _except_,
3278      _lib.bad.alloc_); it returns a non-null pointer otherwise If the allo-
3279      cation function is declared  with  an  empty  exception-specification,
3280      throw(), it returns null to indicate failure to allocate storage and a
3281      non-null pointer otherwise.
3282 
3283      So check for a null exception spec on the op new we just called.  */
3284 
3285   nothrow = TYPE_NOTHROW_P (TREE_TYPE (alloc_fn));
3286   check_new
3287     = flag_check_new || (nothrow && !std_placement_new_fn_p (alloc_fn));
3288 
3289   if (cookie_size)
3290     {
3291       tree cookie;
3292       tree cookie_ptr;
3293       tree size_ptr_type;
3294 
3295       /* Adjust so we're pointing to the start of the object.  */
3296       data_addr = fold_build_pointer_plus (alloc_node, cookie_size);
3297 
3298       /* Store the number of bytes allocated so that we can know how
3299 	 many elements to destroy later.  We use the last sizeof
3300 	 (size_t) bytes to store the number of elements.  */
3301       cookie_ptr = size_binop (MINUS_EXPR, cookie_size, size_in_bytes (sizetype));
3302       cookie_ptr = fold_build_pointer_plus_loc (input_location,
3303 						alloc_node, cookie_ptr);
3304       size_ptr_type = build_pointer_type (sizetype);
3305       cookie_ptr = fold_convert (size_ptr_type, cookie_ptr);
3306       cookie = cp_build_fold_indirect_ref (cookie_ptr);
3307 
3308       cookie_expr = build2 (MODIFY_EXPR, sizetype, cookie, nelts);
3309 
3310       if (targetm.cxx.cookie_has_size ())
3311 	{
3312 	  /* Also store the element size.  */
3313 	  cookie_ptr = fold_build_pointer_plus (cookie_ptr,
3314 			       fold_build1_loc (input_location,
3315 						NEGATE_EXPR, sizetype,
3316 						size_in_bytes (sizetype)));
3317 
3318 	  cookie = cp_build_fold_indirect_ref (cookie_ptr);
3319 	  cookie = build2 (MODIFY_EXPR, sizetype, cookie,
3320 			   size_in_bytes (elt_type));
3321 	  cookie_expr = build2 (COMPOUND_EXPR, TREE_TYPE (cookie_expr),
3322 				cookie, cookie_expr);
3323 	}
3324     }
3325   else
3326     {
3327       cookie_expr = NULL_TREE;
3328       data_addr = alloc_node;
3329     }
3330 
3331   /* Now use a pointer to the type we've actually allocated.  */
3332 
3333   /* But we want to operate on a non-const version to start with,
3334      since we'll be modifying the elements.  */
3335   non_const_pointer_type = build_pointer_type
3336     (cp_build_qualified_type (type, cp_type_quals (type) & ~TYPE_QUAL_CONST));
3337 
3338   data_addr = fold_convert (non_const_pointer_type, data_addr);
3339   /* Any further uses of alloc_node will want this type, too.  */
3340   alloc_node = fold_convert (non_const_pointer_type, alloc_node);
3341 
3342   /* Now initialize the allocated object.  Note that we preevaluate the
3343      initialization expression, apart from the actual constructor call or
3344      assignment--we do this because we want to delay the allocation as long
3345      as possible in order to minimize the size of the exception region for
3346      placement delete.  */
3347   if (is_initialized)
3348     {
3349       bool stable;
3350       bool explicit_value_init_p = false;
3351 
3352       if (*init != NULL && (*init)->is_empty ())
3353 	{
3354 	  *init = NULL;
3355 	  explicit_value_init_p = true;
3356 	}
3357 
3358       if (processing_template_decl && explicit_value_init_p)
3359 	{
3360 	  /* build_value_init doesn't work in templates, and we don't need
3361 	     the initializer anyway since we're going to throw it away and
3362 	     rebuild it at instantiation time, so just build up a single
3363 	     constructor call to get any appropriate diagnostics.  */
3364 	  init_expr = cp_build_fold_indirect_ref (data_addr);
3365 	  if (type_build_ctor_call (elt_type))
3366 	    init_expr = build_special_member_call (init_expr,
3367 						   complete_ctor_identifier,
3368 						   init, elt_type,
3369 						   LOOKUP_NORMAL,
3370 						   complain);
3371 	  stable = stabilize_init (init_expr, &init_preeval_expr);
3372 	}
3373       else if (array_p)
3374 	{
3375 	  tree vecinit = NULL_TREE;
3376 	  if (vec_safe_length (*init) == 1
3377 	      && DIRECT_LIST_INIT_P ((**init)[0]))
3378 	    {
3379 	      vecinit = (**init)[0];
3380 	      if (CONSTRUCTOR_NELTS (vecinit) == 0)
3381 		/* List-value-initialization, leave it alone.  */;
3382 	      else
3383 		{
3384 		  tree arraytype, domain;
3385 		  if (TREE_CONSTANT (nelts))
3386 		    domain = compute_array_index_type (NULL_TREE, nelts,
3387 						       complain);
3388 		  else
3389 		    /* We'll check the length at runtime.  */
3390 		    domain = NULL_TREE;
3391 		  arraytype = build_cplus_array_type (type, domain);
3392 		  vecinit = digest_init (arraytype, vecinit, complain);
3393 		}
3394 	    }
3395 	  else if (*init)
3396             {
3397               if (complain & tf_error)
3398                 error ("parenthesized initializer in array new");
3399 	      return error_mark_node;
3400             }
3401 	  init_expr
3402 	    = build_vec_init (data_addr,
3403 			      cp_build_binary_op (input_location,
3404 						  MINUS_EXPR, outer_nelts,
3405 						  integer_one_node,
3406 						  complain),
3407 			      vecinit,
3408 			      explicit_value_init_p,
3409 			      /*from_array=*/0,
3410                               complain);
3411 
3412 	  /* An array initialization is stable because the initialization
3413 	     of each element is a full-expression, so the temporaries don't
3414 	     leak out.  */
3415 	  stable = true;
3416 	}
3417       else
3418 	{
3419 	  init_expr = cp_build_fold_indirect_ref (data_addr);
3420 
3421 	  if (type_build_ctor_call (type) && !explicit_value_init_p)
3422 	    {
3423 	      init_expr = build_special_member_call (init_expr,
3424 						     complete_ctor_identifier,
3425 						     init, elt_type,
3426 						     LOOKUP_NORMAL,
3427                                                      complain);
3428 	    }
3429 	  else if (explicit_value_init_p)
3430 	    {
3431 	      /* Something like `new int()'.  NO_CLEANUP is needed so
3432 		 we don't try and build a (possibly ill-formed)
3433 		 destructor.  */
3434 	      tree val = build_value_init (type, complain | tf_no_cleanup);
3435 	      if (val == error_mark_node)
3436 		return error_mark_node;
3437 	      init_expr = build2 (INIT_EXPR, type, init_expr, val);
3438 	    }
3439 	  else
3440 	    {
3441 	      tree ie;
3442 
3443 	      /* We are processing something like `new int (10)', which
3444 		 means allocate an int, and initialize it with 10.  */
3445 
3446 	      ie = build_x_compound_expr_from_vec (*init, "new initializer",
3447 						   complain);
3448 	      init_expr = cp_build_modify_expr (input_location, init_expr,
3449 						INIT_EXPR, ie, complain);
3450 	    }
3451 	  /* If the initializer uses C++14 aggregate NSDMI that refer to the
3452 	     object being initialized, replace them now and don't try to
3453 	     preevaluate.  */
3454 	  bool had_placeholder = false;
3455 	  if (!processing_template_decl
3456 	      && TREE_CODE (init_expr) == INIT_EXPR)
3457 	    TREE_OPERAND (init_expr, 1)
3458 	      = replace_placeholders (TREE_OPERAND (init_expr, 1),
3459 				      TREE_OPERAND (init_expr, 0),
3460 				      &had_placeholder);
3461 	  stable = (!had_placeholder
3462 		    && stabilize_init (init_expr, &init_preeval_expr));
3463 	}
3464 
3465       if (init_expr == error_mark_node)
3466 	return error_mark_node;
3467 
3468       /* If any part of the object initialization terminates by throwing an
3469 	 exception and a suitable deallocation function can be found, the
3470 	 deallocation function is called to free the memory in which the
3471 	 object was being constructed, after which the exception continues
3472 	 to propagate in the context of the new-expression. If no
3473 	 unambiguous matching deallocation function can be found,
3474 	 propagating the exception does not cause the object's memory to be
3475 	 freed.  */
3476       if (flag_exceptions)
3477 	{
3478 	  enum tree_code dcode = array_p ? VEC_DELETE_EXPR : DELETE_EXPR;
3479 	  tree cleanup;
3480 
3481 	  /* The Standard is unclear here, but the right thing to do
3482 	     is to use the same method for finding deallocation
3483 	     functions that we use for finding allocation functions.  */
3484 	  cleanup = (build_op_delete_call
3485 		     (dcode,
3486 		      alloc_node,
3487 		      size,
3488 		      globally_qualified_p,
3489 		      placement_allocation_fn_p ? alloc_call : NULL_TREE,
3490 		      alloc_fn,
3491 		      complain));
3492 
3493 	  if (!cleanup)
3494 	    /* We're done.  */;
3495 	  else if (stable)
3496 	    /* This is much simpler if we were able to preevaluate all of
3497 	       the arguments to the constructor call.  */
3498 	    {
3499 	      /* CLEANUP is compiler-generated, so no diagnostics.  */
3500 	      TREE_NO_WARNING (cleanup) = true;
3501 	      init_expr = build2 (TRY_CATCH_EXPR, void_type_node,
3502 				  init_expr, cleanup);
3503 	      /* Likewise, this try-catch is compiler-generated.  */
3504 	      TREE_NO_WARNING (init_expr) = true;
3505 	    }
3506 	  else
3507 	    /* Ack!  First we allocate the memory.  Then we set our sentry
3508 	       variable to true, and expand a cleanup that deletes the
3509 	       memory if sentry is true.  Then we run the constructor, and
3510 	       finally clear the sentry.
3511 
3512 	       We need to do this because we allocate the space first, so
3513 	       if there are any temporaries with cleanups in the
3514 	       constructor args and we weren't able to preevaluate them, we
3515 	       need this EH region to extend until end of full-expression
3516 	       to preserve nesting.  */
3517 	    {
3518 	      tree end, sentry, begin;
3519 
3520 	      begin = get_target_expr (boolean_true_node);
3521 	      CLEANUP_EH_ONLY (begin) = 1;
3522 
3523 	      sentry = TARGET_EXPR_SLOT (begin);
3524 
3525 	      /* CLEANUP is compiler-generated, so no diagnostics.  */
3526 	      TREE_NO_WARNING (cleanup) = true;
3527 
3528 	      TARGET_EXPR_CLEANUP (begin)
3529 		= build3 (COND_EXPR, void_type_node, sentry,
3530 			  cleanup, void_node);
3531 
3532 	      end = build2 (MODIFY_EXPR, TREE_TYPE (sentry),
3533 			    sentry, boolean_false_node);
3534 
3535 	      init_expr
3536 		= build2 (COMPOUND_EXPR, void_type_node, begin,
3537 			  build2 (COMPOUND_EXPR, void_type_node, init_expr,
3538 				  end));
3539 	      /* Likewise, this is compiler-generated.  */
3540 	      TREE_NO_WARNING (init_expr) = true;
3541 	    }
3542 	}
3543     }
3544   else
3545     init_expr = NULL_TREE;
3546 
3547   /* Now build up the return value in reverse order.  */
3548 
3549   rval = data_addr;
3550 
3551   if (init_expr)
3552     rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), init_expr, rval);
3553   if (cookie_expr)
3554     rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), cookie_expr, rval);
3555 
3556   if (rval == data_addr)
3557     /* If we don't have an initializer or a cookie, strip the TARGET_EXPR
3558        and return the call (which doesn't need to be adjusted).  */
3559     rval = TARGET_EXPR_INITIAL (alloc_expr);
3560   else
3561     {
3562       if (check_new)
3563 	{
3564 	  tree ifexp = cp_build_binary_op (input_location,
3565 					   NE_EXPR, alloc_node,
3566 					   nullptr_node,
3567 					   complain);
3568 	  rval = build_conditional_expr (input_location, ifexp, rval,
3569 					 alloc_node, complain);
3570 	}
3571 
3572       /* Perform the allocation before anything else, so that ALLOC_NODE
3573 	 has been initialized before we start using it.  */
3574       rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), alloc_expr, rval);
3575     }
3576 
3577   if (init_preeval_expr)
3578     rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), init_preeval_expr, rval);
3579 
3580   /* A new-expression is never an lvalue.  */
3581   gcc_assert (!obvalue_p (rval));
3582 
3583   return convert (pointer_type, rval);
3584 }
3585 
3586 /* Generate a representation for a C++ "new" expression.  *PLACEMENT
3587    is a vector of placement-new arguments (or NULL if none).  If NELTS
3588    is NULL, TYPE is the type of the storage to be allocated.  If NELTS
3589    is not NULL, then this is an array-new allocation; TYPE is the type
3590    of the elements in the array and NELTS is the number of elements in
3591    the array.  *INIT, if non-NULL, is the initializer for the new
3592    object, or an empty vector to indicate an initializer of "()".  If
3593    USE_GLOBAL_NEW is true, then the user explicitly wrote "::new"
3594    rather than just "new".  This may change PLACEMENT and INIT.  */
3595 
3596 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)3597 build_new (vec<tree, va_gc> **placement, tree type, tree nelts,
3598 	   vec<tree, va_gc> **init, int use_global_new, tsubst_flags_t complain)
3599 {
3600   tree rval;
3601   vec<tree, va_gc> *orig_placement = NULL;
3602   tree orig_nelts = NULL_TREE;
3603   vec<tree, va_gc> *orig_init = NULL;
3604 
3605   if (type == error_mark_node)
3606     return error_mark_node;
3607 
3608   if (nelts == NULL_TREE
3609       /* Don't do auto deduction where it might affect mangling.  */
3610       && (!processing_template_decl || at_function_scope_p ()))
3611     {
3612       tree auto_node = type_uses_auto (type);
3613       if (auto_node)
3614 	{
3615 	  tree d_init = NULL_TREE;
3616 	  if (vec_safe_length (*init) == 1)
3617 	    {
3618 	      d_init = (**init)[0];
3619 	      d_init = resolve_nondeduced_context (d_init, complain);
3620 	    }
3621 	  type = do_auto_deduction (type, d_init, auto_node, complain);
3622 	}
3623     }
3624 
3625   if (processing_template_decl)
3626     {
3627       if (dependent_type_p (type)
3628 	  || any_type_dependent_arguments_p (*placement)
3629 	  || (nelts && type_dependent_expression_p (nelts))
3630 	  || (nelts && *init)
3631 	  || any_type_dependent_arguments_p (*init))
3632 	return build_raw_new_expr (*placement, type, nelts, *init,
3633 				   use_global_new);
3634 
3635       orig_placement = make_tree_vector_copy (*placement);
3636       orig_nelts = nelts;
3637       if (*init)
3638 	{
3639 	  orig_init = make_tree_vector_copy (*init);
3640 	  /* Also copy any CONSTRUCTORs in *init, since reshape_init and
3641 	     digest_init clobber them in place.  */
3642 	  for (unsigned i = 0; i < orig_init->length(); ++i)
3643 	    {
3644 	      tree e = (**init)[i];
3645 	      if (TREE_CODE (e) == CONSTRUCTOR)
3646 		(**init)[i] = copy_node (e);
3647 	    }
3648 	}
3649 
3650       make_args_non_dependent (*placement);
3651       if (nelts)
3652 	nelts = build_non_dependent_expr (nelts);
3653       make_args_non_dependent (*init);
3654     }
3655 
3656   if (nelts)
3657     {
3658       if (!build_expr_type_conversion (WANT_INT | WANT_ENUM, nelts, false))
3659         {
3660           if (complain & tf_error)
3661             permerror (input_location, "size in array new must have integral type");
3662           else
3663             return error_mark_node;
3664         }
3665 
3666       /* Try to determine the constant value only for the purposes
3667 	 of the diagnostic below but continue to use the original
3668 	 value and handle const folding later.  */
3669       const_tree cst_nelts = fold_non_dependent_expr (nelts);
3670 
3671       /* The expression in a noptr-new-declarator is erroneous if it's of
3672 	 non-class type and its value before converting to std::size_t is
3673 	 less than zero. ... If the expression is a constant expression,
3674 	 the program is ill-fomed.  */
3675       if (TREE_CODE (cst_nelts) == INTEGER_CST
3676 	  && tree_int_cst_sgn (cst_nelts) == -1)
3677 	{
3678 	  if (complain & tf_error)
3679 	    error ("size of array is negative");
3680 	  return error_mark_node;
3681 	}
3682 
3683       nelts = mark_rvalue_use (nelts);
3684       nelts = cp_save_expr (cp_convert (sizetype, nelts, complain));
3685     }
3686 
3687   /* ``A reference cannot be created by the new operator.  A reference
3688      is not an object (8.2.2, 8.4.3), so a pointer to it could not be
3689      returned by new.'' ARM 5.3.3 */
3690   if (TREE_CODE (type) == REFERENCE_TYPE)
3691     {
3692       if (complain & tf_error)
3693         error ("new cannot be applied to a reference type");
3694       else
3695         return error_mark_node;
3696       type = TREE_TYPE (type);
3697     }
3698 
3699   if (TREE_CODE (type) == FUNCTION_TYPE)
3700     {
3701       if (complain & tf_error)
3702         error ("new cannot be applied to a function type");
3703       return error_mark_node;
3704     }
3705 
3706   /* The type allocated must be complete.  If the new-type-id was
3707      "T[N]" then we are just checking that "T" is complete here, but
3708      that is equivalent, since the value of "N" doesn't matter.  */
3709   if (!complete_type_or_maybe_complain (type, NULL_TREE, complain))
3710     return error_mark_node;
3711 
3712   rval = build_new_1 (placement, type, nelts, init, use_global_new, complain);
3713   if (rval == error_mark_node)
3714     return error_mark_node;
3715 
3716   if (processing_template_decl)
3717     {
3718       tree ret = build_raw_new_expr (orig_placement, type, orig_nelts,
3719 				     orig_init, use_global_new);
3720       release_tree_vector (orig_placement);
3721       release_tree_vector (orig_init);
3722       return ret;
3723     }
3724 
3725   /* Wrap it in a NOP_EXPR so warn_if_unused_value doesn't complain.  */
3726   rval = build1 (NOP_EXPR, TREE_TYPE (rval), rval);
3727   TREE_NO_WARNING (rval) = 1;
3728 
3729   return rval;
3730 }
3731 
3732 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)3733 build_vec_delete_1 (tree base, tree maxindex, tree type,
3734 		    special_function_kind auto_delete_vec,
3735 		    int use_global_delete, tsubst_flags_t complain)
3736 {
3737   tree virtual_size;
3738   tree ptype = build_pointer_type (type = complete_type (type));
3739   tree size_exp;
3740 
3741   /* Temporary variables used by the loop.  */
3742   tree tbase, tbase_init;
3743 
3744   /* This is the body of the loop that implements the deletion of a
3745      single element, and moves temp variables to next elements.  */
3746   tree body;
3747 
3748   /* This is the LOOP_EXPR that governs the deletion of the elements.  */
3749   tree loop = 0;
3750 
3751   /* This is the thing that governs what to do after the loop has run.  */
3752   tree deallocate_expr = 0;
3753 
3754   /* This is the BIND_EXPR which holds the outermost iterator of the
3755      loop.  It is convenient to set this variable up and test it before
3756      executing any other code in the loop.
3757      This is also the containing expression returned by this function.  */
3758   tree controller = NULL_TREE;
3759   tree tmp;
3760 
3761   /* We should only have 1-D arrays here.  */
3762   gcc_assert (TREE_CODE (type) != ARRAY_TYPE);
3763 
3764   if (base == error_mark_node || maxindex == error_mark_node)
3765     return error_mark_node;
3766 
3767   if (!COMPLETE_TYPE_P (type))
3768     {
3769       if ((complain & tf_warning)
3770 	  && warning (OPT_Wdelete_incomplete,
3771 		      "possible problem detected in invocation of "
3772 		      "delete [] operator:"))
3773        {
3774          cxx_incomplete_type_diagnostic (base, type, DK_WARNING);
3775          inform (input_location, "neither the destructor nor the "
3776                  "class-specific operator delete [] will be called, "
3777                  "even if they are declared when the class is defined");
3778        }
3779       /* This size won't actually be used.  */
3780       size_exp = size_one_node;
3781       goto no_destructor;
3782     }
3783 
3784   size_exp = size_in_bytes (type);
3785 
3786   if (! MAYBE_CLASS_TYPE_P (type))
3787     goto no_destructor;
3788   else if (TYPE_HAS_TRIVIAL_DESTRUCTOR (type))
3789     {
3790       /* Make sure the destructor is callable.  */
3791       if (type_build_dtor_call (type))
3792 	{
3793 	  tmp = build_delete (ptype, base, sfk_complete_destructor,
3794 			      LOOKUP_NORMAL|LOOKUP_DESTRUCTOR, 1,
3795 			      complain);
3796 	  if (tmp == error_mark_node)
3797 	    return error_mark_node;
3798 	}
3799       goto no_destructor;
3800     }
3801 
3802   /* The below is short by the cookie size.  */
3803   virtual_size = size_binop (MULT_EXPR, size_exp,
3804 			     fold_convert (sizetype, maxindex));
3805 
3806   tbase = create_temporary_var (ptype);
3807   tbase_init
3808     = cp_build_modify_expr (input_location, tbase, NOP_EXPR,
3809 			    fold_build_pointer_plus_loc (input_location,
3810 							 fold_convert (ptype,
3811 								       base),
3812 							 virtual_size),
3813 			    complain);
3814   if (tbase_init == error_mark_node)
3815     return error_mark_node;
3816   controller = build3 (BIND_EXPR, void_type_node, tbase,
3817 		       NULL_TREE, NULL_TREE);
3818   TREE_SIDE_EFFECTS (controller) = 1;
3819 
3820   body = build1 (EXIT_EXPR, void_type_node,
3821 		 build2 (EQ_EXPR, boolean_type_node, tbase,
3822 			 fold_convert (ptype, base)));
3823   tmp = fold_build1_loc (input_location, NEGATE_EXPR, sizetype, size_exp);
3824   tmp = fold_build_pointer_plus (tbase, tmp);
3825   tmp = cp_build_modify_expr (input_location, tbase, NOP_EXPR, tmp, complain);
3826   if (tmp == error_mark_node)
3827     return error_mark_node;
3828   body = build_compound_expr (input_location, body, tmp);
3829   tmp = build_delete (ptype, tbase, sfk_complete_destructor,
3830 		      LOOKUP_NORMAL|LOOKUP_DESTRUCTOR, 1,
3831 		      complain);
3832   if (tmp == error_mark_node)
3833     return error_mark_node;
3834   body = build_compound_expr (input_location, body, tmp);
3835 
3836   loop = build1 (LOOP_EXPR, void_type_node, body);
3837   loop = build_compound_expr (input_location, tbase_init, loop);
3838 
3839  no_destructor:
3840   /* Delete the storage if appropriate.  */
3841   if (auto_delete_vec == sfk_deleting_destructor)
3842     {
3843       tree base_tbd;
3844 
3845       /* The below is short by the cookie size.  */
3846       virtual_size = size_binop (MULT_EXPR, size_exp,
3847 				 fold_convert (sizetype, maxindex));
3848 
3849       if (! TYPE_VEC_NEW_USES_COOKIE (type))
3850 	/* no header */
3851 	base_tbd = base;
3852       else
3853 	{
3854 	  tree cookie_size;
3855 
3856 	  cookie_size = targetm.cxx.get_cookie_size (type);
3857 	  base_tbd = cp_build_binary_op (input_location,
3858 					 MINUS_EXPR,
3859 					 cp_convert (string_type_node,
3860 						     base, complain),
3861 					 cookie_size,
3862 					 complain);
3863 	  if (base_tbd == error_mark_node)
3864 	    return error_mark_node;
3865 	  base_tbd = cp_convert (ptype, base_tbd, complain);
3866 	  /* True size with header.  */
3867 	  virtual_size = size_binop (PLUS_EXPR, virtual_size, cookie_size);
3868 	}
3869 
3870       deallocate_expr = build_op_delete_call (VEC_DELETE_EXPR,
3871 					      base_tbd, virtual_size,
3872 					      use_global_delete & 1,
3873 					      /*placement=*/NULL_TREE,
3874 					      /*alloc_fn=*/NULL_TREE,
3875 					      complain);
3876     }
3877 
3878   body = loop;
3879   if (!deallocate_expr)
3880     ;
3881   else if (!body)
3882     body = deallocate_expr;
3883   else
3884     /* The delete operator mist be called, even if a destructor
3885        throws.  */
3886     body = build2 (TRY_FINALLY_EXPR, void_type_node, body, deallocate_expr);
3887 
3888   if (!body)
3889     body = integer_zero_node;
3890 
3891   /* Outermost wrapper: If pointer is null, punt.  */
3892   tree cond = build2_loc (input_location, NE_EXPR, boolean_type_node, base,
3893 			  fold_convert (TREE_TYPE (base), nullptr_node));
3894   /* This is a compiler generated comparison, don't emit
3895      e.g. -Wnonnull-compare warning for it.  */
3896   TREE_NO_WARNING (cond) = 1;
3897   body = build3_loc (input_location, COND_EXPR, void_type_node,
3898 		     cond, body, integer_zero_node);
3899   COND_EXPR_IS_VEC_DELETE (body) = true;
3900   body = build1 (NOP_EXPR, void_type_node, body);
3901 
3902   if (controller)
3903     {
3904       TREE_OPERAND (controller, 1) = body;
3905       body = controller;
3906     }
3907 
3908   if (TREE_CODE (base) == SAVE_EXPR)
3909     /* Pre-evaluate the SAVE_EXPR outside of the BIND_EXPR.  */
3910     body = build2 (COMPOUND_EXPR, void_type_node, base, body);
3911 
3912   return convert_to_void (body, ICV_CAST, complain);
3913 }
3914 
3915 /* Create an unnamed variable of the indicated TYPE.  */
3916 
3917 tree
create_temporary_var(tree type)3918 create_temporary_var (tree type)
3919 {
3920   tree decl;
3921 
3922   decl = build_decl (input_location,
3923 		     VAR_DECL, NULL_TREE, type);
3924   TREE_USED (decl) = 1;
3925   DECL_ARTIFICIAL (decl) = 1;
3926   DECL_IGNORED_P (decl) = 1;
3927   DECL_CONTEXT (decl) = current_function_decl;
3928 
3929   return decl;
3930 }
3931 
3932 /* Create a new temporary variable of the indicated TYPE, initialized
3933    to INIT.
3934 
3935    It is not entered into current_binding_level, because that breaks
3936    things when it comes time to do final cleanups (which take place
3937    "outside" the binding contour of the function).  */
3938 
3939 tree
get_temp_regvar(tree type,tree init)3940 get_temp_regvar (tree type, tree init)
3941 {
3942   tree decl;
3943 
3944   decl = create_temporary_var (type);
3945   add_decl_expr (decl);
3946 
3947   finish_expr_stmt (cp_build_modify_expr (input_location, decl, INIT_EXPR,
3948 					  init, tf_warning_or_error));
3949 
3950   return decl;
3951 }
3952 
3953 /* Subroutine of build_vec_init.  Returns true if assigning to an array of
3954    INNER_ELT_TYPE from INIT is trivial.  */
3955 
3956 static bool
vec_copy_assign_is_trivial(tree inner_elt_type,tree init)3957 vec_copy_assign_is_trivial (tree inner_elt_type, tree init)
3958 {
3959   tree fromtype = inner_elt_type;
3960   if (lvalue_p (init))
3961     fromtype = cp_build_reference_type (fromtype, /*rval*/false);
3962   return is_trivially_xible (MODIFY_EXPR, inner_elt_type, fromtype);
3963 }
3964 
3965 /* Subroutine of build_vec_init: Check that the array has at least N
3966    elements.  Other parameters are local variables in build_vec_init.  */
3967 
3968 void
finish_length_check(tree atype,tree iterator,tree obase,unsigned n)3969 finish_length_check (tree atype, tree iterator, tree obase, unsigned n)
3970 {
3971   tree nelts = build_int_cst (ptrdiff_type_node, n - 1);
3972   if (TREE_CODE (atype) != ARRAY_TYPE)
3973     {
3974       if (flag_exceptions)
3975 	{
3976 	  tree c = fold_build2 (LT_EXPR, boolean_type_node, iterator,
3977 				nelts);
3978 	  c = build3 (COND_EXPR, void_type_node, c,
3979 		      throw_bad_array_new_length (), void_node);
3980 	  finish_expr_stmt (c);
3981 	}
3982       /* Don't check an array new when -fno-exceptions.  */
3983     }
3984   else if (sanitize_flags_p (SANITIZE_BOUNDS)
3985 	   && current_function_decl != NULL_TREE)
3986     {
3987       /* Make sure the last element of the initializer is in bounds. */
3988       finish_expr_stmt
3989 	(ubsan_instrument_bounds
3990 	 (input_location, obase, &nelts, /*ignore_off_by_one*/false));
3991     }
3992 }
3993 
3994 /* `build_vec_init' returns tree structure that performs
3995    initialization of a vector of aggregate types.
3996 
3997    BASE is a reference to the vector, of ARRAY_TYPE, or a pointer
3998      to the first element, of POINTER_TYPE.
3999    MAXINDEX is the maximum index of the array (one less than the
4000      number of elements).  It is only used if BASE is a pointer or
4001      TYPE_DOMAIN (TREE_TYPE (BASE)) == NULL_TREE.
4002 
4003    INIT is the (possibly NULL) initializer.
4004 
4005    If EXPLICIT_VALUE_INIT_P is true, then INIT must be NULL.  All
4006    elements in the array are value-initialized.
4007 
4008    FROM_ARRAY is 0 if we should init everything with INIT
4009    (i.e., every element initialized from INIT).
4010    FROM_ARRAY is 1 if we should index into INIT in parallel
4011    with initialization of DECL.
4012    FROM_ARRAY is 2 if we should index into INIT in parallel,
4013    but use assignment instead of initialization.  */
4014 
4015 tree
build_vec_init(tree base,tree maxindex,tree init,bool explicit_value_init_p,int from_array,tsubst_flags_t complain)4016 build_vec_init (tree base, tree maxindex, tree init,
4017 		bool explicit_value_init_p,
4018 		int from_array, tsubst_flags_t complain)
4019 {
4020   tree rval;
4021   tree base2 = NULL_TREE;
4022   tree itype = NULL_TREE;
4023   tree iterator;
4024   /* The type of BASE.  */
4025   tree atype = TREE_TYPE (base);
4026   /* The type of an element in the array.  */
4027   tree type = TREE_TYPE (atype);
4028   /* The element type reached after removing all outer array
4029      types.  */
4030   tree inner_elt_type;
4031   /* The type of a pointer to an element in the array.  */
4032   tree ptype;
4033   tree stmt_expr;
4034   tree compound_stmt;
4035   int destroy_temps;
4036   tree try_block = NULL_TREE;
4037   HOST_WIDE_INT num_initialized_elts = 0;
4038   bool is_global;
4039   tree obase = base;
4040   bool xvalue = false;
4041   bool errors = false;
4042   location_t loc = (init ? EXPR_LOC_OR_LOC (init, input_location)
4043 		    : location_of (base));
4044 
4045   if (TREE_CODE (atype) == ARRAY_TYPE && TYPE_DOMAIN (atype))
4046     maxindex = array_type_nelts (atype);
4047 
4048   if (maxindex == NULL_TREE || maxindex == error_mark_node)
4049     return error_mark_node;
4050 
4051   maxindex = maybe_constant_value (maxindex);
4052   if (explicit_value_init_p)
4053     gcc_assert (!init);
4054 
4055   inner_elt_type = strip_array_types (type);
4056 
4057   /* Look through the TARGET_EXPR around a compound literal.  */
4058   if (init && TREE_CODE (init) == TARGET_EXPR
4059       && TREE_CODE (TARGET_EXPR_INITIAL (init)) == CONSTRUCTOR
4060       && from_array != 2)
4061     init = TARGET_EXPR_INITIAL (init);
4062 
4063   bool direct_init = false;
4064   if (from_array && init && BRACE_ENCLOSED_INITIALIZER_P (init)
4065       && CONSTRUCTOR_NELTS (init) == 1)
4066     {
4067       tree elt = CONSTRUCTOR_ELT (init, 0)->value;
4068       if (TREE_CODE (TREE_TYPE (elt)) == ARRAY_TYPE)
4069 	{
4070 	  direct_init = DIRECT_LIST_INIT_P (init);
4071 	  init = elt;
4072 	}
4073     }
4074 
4075   /* If we have a braced-init-list or string constant, make sure that the array
4076      is big enough for all the initializers.  */
4077   bool length_check = (init
4078 		       && (TREE_CODE (init) == STRING_CST
4079 			   || (TREE_CODE (init) == CONSTRUCTOR
4080 			       && CONSTRUCTOR_NELTS (init) > 0))
4081 		       && !TREE_CONSTANT (maxindex));
4082 
4083   if (init
4084       && TREE_CODE (atype) == ARRAY_TYPE
4085       && TREE_CONSTANT (maxindex)
4086       && (from_array == 2
4087 	  ? vec_copy_assign_is_trivial (inner_elt_type, init)
4088 	  : !TYPE_NEEDS_CONSTRUCTING (type))
4089       && ((TREE_CODE (init) == CONSTRUCTOR
4090 	   && (BRACE_ENCLOSED_INITIALIZER_P (init)
4091 	       || (same_type_ignoring_top_level_qualifiers_p
4092 		   (atype, TREE_TYPE (init))))
4093 	   /* Don't do this if the CONSTRUCTOR might contain something
4094 	      that might throw and require us to clean up.  */
4095 	   && (vec_safe_is_empty (CONSTRUCTOR_ELTS (init))
4096 	       || ! TYPE_HAS_NONTRIVIAL_DESTRUCTOR (inner_elt_type)))
4097 	  || from_array))
4098     {
4099       /* Do non-default initialization of trivial arrays resulting from
4100 	 brace-enclosed initializers.  In this case, digest_init and
4101 	 store_constructor will handle the semantics for us.  */
4102 
4103       if (BRACE_ENCLOSED_INITIALIZER_P (init))
4104 	init = digest_init (atype, init, complain);
4105       stmt_expr = build2 (INIT_EXPR, atype, base, init);
4106       return stmt_expr;
4107     }
4108 
4109   maxindex = cp_convert (ptrdiff_type_node, maxindex, complain);
4110   maxindex = fold_simple (maxindex);
4111 
4112   if (TREE_CODE (atype) == ARRAY_TYPE)
4113     {
4114       ptype = build_pointer_type (type);
4115       base = decay_conversion (base, complain);
4116       if (base == error_mark_node)
4117 	return error_mark_node;
4118       base = cp_convert (ptype, base, complain);
4119     }
4120   else
4121     ptype = atype;
4122 
4123   /* The code we are generating looks like:
4124      ({
4125        T* t1 = (T*) base;
4126        T* rval = t1;
4127        ptrdiff_t iterator = maxindex;
4128        try {
4129 	 for (; iterator != -1; --iterator) {
4130 	   ... initialize *t1 ...
4131 	   ++t1;
4132 	 }
4133        } catch (...) {
4134 	 ... destroy elements that were constructed ...
4135        }
4136        rval;
4137      })
4138 
4139      We can omit the try and catch blocks if we know that the
4140      initialization will never throw an exception, or if the array
4141      elements do not have destructors.  We can omit the loop completely if
4142      the elements of the array do not have constructors.
4143 
4144      We actually wrap the entire body of the above in a STMT_EXPR, for
4145      tidiness.
4146 
4147      When copying from array to another, when the array elements have
4148      only trivial copy constructors, we should use __builtin_memcpy
4149      rather than generating a loop.  That way, we could take advantage
4150      of whatever cleverness the back end has for dealing with copies
4151      of blocks of memory.  */
4152 
4153   is_global = begin_init_stmts (&stmt_expr, &compound_stmt);
4154   destroy_temps = stmts_are_full_exprs_p ();
4155   current_stmt_tree ()->stmts_are_full_exprs_p = 0;
4156   rval = get_temp_regvar (ptype, base);
4157   base = get_temp_regvar (ptype, rval);
4158   iterator = get_temp_regvar (ptrdiff_type_node, maxindex);
4159 
4160   /* If initializing one array from another, initialize element by
4161      element.  We rely upon the below calls to do the argument
4162      checking.  Evaluate the initializer before entering the try block.  */
4163   if (from_array && init && TREE_CODE (init) != CONSTRUCTOR)
4164     {
4165       if (lvalue_kind (init) & clk_rvalueref)
4166 	xvalue = true;
4167       base2 = decay_conversion (init, complain);
4168       if (base2 == error_mark_node)
4169 	return error_mark_node;
4170       itype = TREE_TYPE (base2);
4171       base2 = get_temp_regvar (itype, base2);
4172       itype = TREE_TYPE (itype);
4173     }
4174 
4175   /* Protect the entire array initialization so that we can destroy
4176      the partially constructed array if an exception is thrown.
4177      But don't do this if we're assigning.  */
4178   if (flag_exceptions && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
4179       && from_array != 2)
4180     {
4181       try_block = begin_try_block ();
4182     }
4183 
4184   /* Should we try to create a constant initializer?  */
4185   bool try_const = (TREE_CODE (atype) == ARRAY_TYPE
4186 		    && TREE_CONSTANT (maxindex)
4187 		    && (init ? TREE_CODE (init) == CONSTRUCTOR
4188 			: (type_has_constexpr_default_constructor
4189 			   (inner_elt_type)))
4190 		    && (literal_type_p (inner_elt_type)
4191 			|| TYPE_HAS_CONSTEXPR_CTOR (inner_elt_type)));
4192   vec<constructor_elt, va_gc> *const_vec = NULL;
4193   bool saw_non_const = false;
4194   /* If we're initializing a static array, we want to do static
4195      initialization of any elements with constant initializers even if
4196      some are non-constant.  */
4197   bool do_static_init = (DECL_P (obase) && TREE_STATIC (obase));
4198 
4199   bool empty_list = false;
4200   if (init && BRACE_ENCLOSED_INITIALIZER_P (init)
4201       && CONSTRUCTOR_NELTS (init) == 0)
4202     /* Skip over the handling of non-empty init lists.  */
4203     empty_list = true;
4204 
4205   /* Maybe pull out constant value when from_array? */
4206 
4207   else if (init != NULL_TREE && TREE_CODE (init) == CONSTRUCTOR)
4208     {
4209       /* Do non-default initialization of non-trivial arrays resulting from
4210 	 brace-enclosed initializers.  */
4211       unsigned HOST_WIDE_INT idx;
4212       tree field, elt;
4213       /* If the constructor already has the array type, it's been through
4214 	 digest_init, so we shouldn't try to do anything more.  */
4215       bool digested = same_type_p (atype, TREE_TYPE (init));
4216       from_array = 0;
4217 
4218       if (length_check)
4219 	finish_length_check (atype, iterator, obase, CONSTRUCTOR_NELTS (init));
4220 
4221       if (try_const)
4222 	vec_alloc (const_vec, CONSTRUCTOR_NELTS (init));
4223 
4224       FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (init), idx, field, elt)
4225 	{
4226 	  tree baseref = build1 (INDIRECT_REF, type, base);
4227 	  tree one_init;
4228 
4229 	  num_initialized_elts++;
4230 
4231 	  current_stmt_tree ()->stmts_are_full_exprs_p = 1;
4232 	  if (digested)
4233 	    one_init = build2 (INIT_EXPR, type, baseref, elt);
4234 	  else if (MAYBE_CLASS_TYPE_P (type) || TREE_CODE (type) == ARRAY_TYPE)
4235 	    one_init = build_aggr_init (baseref, elt, 0, complain);
4236 	  else
4237 	    one_init = cp_build_modify_expr (input_location, baseref,
4238 					     NOP_EXPR, elt, complain);
4239 	  if (one_init == error_mark_node)
4240 	    errors = true;
4241 	  if (try_const)
4242 	    {
4243 	      tree e = maybe_constant_init (one_init);
4244 	      if (reduced_constant_expression_p (e))
4245 		{
4246 		  CONSTRUCTOR_APPEND_ELT (const_vec, field, e);
4247 		  if (do_static_init)
4248 		    one_init = NULL_TREE;
4249 		  else
4250 		    one_init = build2 (INIT_EXPR, type, baseref, e);
4251 		}
4252 	      else
4253 		{
4254 		  if (do_static_init)
4255 		    {
4256 		      tree value = build_zero_init (TREE_TYPE (e), NULL_TREE,
4257 						    true);
4258 		      if (value)
4259 			CONSTRUCTOR_APPEND_ELT (const_vec, field, value);
4260 		    }
4261 		  saw_non_const = true;
4262 		}
4263 	    }
4264 
4265 	  if (one_init)
4266 	    finish_expr_stmt (one_init);
4267 	  current_stmt_tree ()->stmts_are_full_exprs_p = 0;
4268 
4269 	  one_init = cp_build_unary_op (PREINCREMENT_EXPR, base, false,
4270 					complain);
4271 	  if (one_init == error_mark_node)
4272 	    errors = true;
4273 	  else
4274 	    finish_expr_stmt (one_init);
4275 
4276 	  one_init = cp_build_unary_op (PREDECREMENT_EXPR, iterator, false,
4277 					complain);
4278 	  if (one_init == error_mark_node)
4279 	    errors = true;
4280 	  else
4281 	    finish_expr_stmt (one_init);
4282 	}
4283 
4284       /* Any elements without explicit initializers get T{}.  */
4285       empty_list = true;
4286     }
4287   else if (init && TREE_CODE (init) == STRING_CST)
4288     {
4289       /* Check that the array is at least as long as the string.  */
4290       if (length_check)
4291 	finish_length_check (atype, iterator, obase,
4292 			     TREE_STRING_LENGTH (init));
4293       tree length = build_int_cst (ptrdiff_type_node,
4294 				   TREE_STRING_LENGTH (init));
4295 
4296       /* Copy the string to the first part of the array.  */
4297       tree alias_set = build_int_cst (build_pointer_type (type), 0);
4298       tree lhs = build2 (MEM_REF, TREE_TYPE (init), base, alias_set);
4299       tree stmt = build2 (MODIFY_EXPR, void_type_node, lhs, init);
4300       finish_expr_stmt (stmt);
4301 
4302       /* Adjust the counter and pointer.  */
4303       stmt = cp_build_binary_op (loc, MINUS_EXPR, iterator, length, complain);
4304       stmt = build2 (MODIFY_EXPR, void_type_node, iterator, stmt);
4305       finish_expr_stmt (stmt);
4306 
4307       stmt = cp_build_binary_op (loc, PLUS_EXPR, base, length, complain);
4308       stmt = build2 (MODIFY_EXPR, void_type_node, base, stmt);
4309       finish_expr_stmt (stmt);
4310 
4311       /* And set the rest of the array to NUL.  */
4312       from_array = 0;
4313       explicit_value_init_p = true;
4314     }
4315   else if (from_array)
4316     {
4317       if (init)
4318 	/* OK, we set base2 above.  */;
4319       else if (CLASS_TYPE_P (type)
4320 	       && ! TYPE_HAS_DEFAULT_CONSTRUCTOR (type))
4321 	{
4322           if (complain & tf_error)
4323             error ("initializer ends prematurely");
4324 	  errors = true;
4325 	}
4326     }
4327 
4328   /* Now, default-initialize any remaining elements.  We don't need to
4329      do that if a) the type does not need constructing, or b) we've
4330      already initialized all the elements.
4331 
4332      We do need to keep going if we're copying an array.  */
4333 
4334   if (try_const && !init)
4335     /* With a constexpr default constructor, which we checked for when
4336        setting try_const above, default-initialization is equivalent to
4337        value-initialization, and build_value_init gives us something more
4338        friendly to maybe_constant_init.  */
4339     explicit_value_init_p = true;
4340   if (from_array
4341       || ((type_build_ctor_call (type) || init || explicit_value_init_p)
4342 	  && ! (tree_fits_shwi_p (maxindex)
4343 		&& (num_initialized_elts
4344 		    == tree_to_shwi (maxindex) + 1))))
4345     {
4346       /* If the ITERATOR is lesser or equal to -1, then we don't have to loop;
4347 	 we've already initialized all the elements.  */
4348       tree for_stmt;
4349       tree elt_init;
4350       tree to;
4351 
4352       for_stmt = begin_for_stmt (NULL_TREE, NULL_TREE);
4353       finish_init_stmt (for_stmt);
4354       finish_for_cond (build2 (GT_EXPR, boolean_type_node, iterator,
4355 			       build_int_cst (TREE_TYPE (iterator), -1)),
4356 		       for_stmt, false, 0);
4357       elt_init = cp_build_unary_op (PREDECREMENT_EXPR, iterator, false,
4358 				    complain);
4359       if (elt_init == error_mark_node)
4360 	errors = true;
4361       finish_for_expr (elt_init, for_stmt);
4362 
4363       to = build1 (INDIRECT_REF, type, base);
4364 
4365       /* If the initializer is {}, then all elements are initialized from T{}.
4366 	 But for non-classes, that's the same as value-initialization.  */
4367       if (empty_list)
4368 	{
4369 	  if (cxx_dialect >= cxx11 && AGGREGATE_TYPE_P (type))
4370 	    {
4371 	      init = build_constructor (init_list_type_node, NULL);
4372 	    }
4373 	  else
4374 	    {
4375 	      init = NULL_TREE;
4376 	      explicit_value_init_p = true;
4377 	    }
4378 	}
4379 
4380       if (from_array)
4381 	{
4382 	  tree from;
4383 
4384 	  if (base2)
4385 	    {
4386 	      from = build1 (INDIRECT_REF, itype, base2);
4387 	      if (xvalue)
4388 		from = move (from);
4389 	      if (direct_init)
4390 		from = build_tree_list (NULL_TREE, from);
4391 	    }
4392 	  else
4393 	    from = NULL_TREE;
4394 
4395 	  if (TREE_CODE (type) == ARRAY_TYPE)
4396 	    elt_init = build_vec_init (to, NULL_TREE, from, /*val_init*/false,
4397 				       from_array, complain);
4398 	  else if (from_array == 2)
4399 	    elt_init = cp_build_modify_expr (input_location, to, NOP_EXPR,
4400 					     from, complain);
4401 	  else if (type_build_ctor_call (type))
4402 	    elt_init = build_aggr_init (to, from, 0, complain);
4403 	  else if (from)
4404 	    elt_init = cp_build_modify_expr (input_location, to, NOP_EXPR, from,
4405 					     complain);
4406 	  else
4407 	    gcc_unreachable ();
4408 	}
4409       else if (TREE_CODE (type) == ARRAY_TYPE)
4410 	{
4411 	  if (init && !BRACE_ENCLOSED_INITIALIZER_P (init))
4412 	    {
4413 	      if ((complain & tf_error))
4414 		error_at (loc, "array must be initialized "
4415 			  "with a brace-enclosed initializer");
4416 	      elt_init = error_mark_node;
4417 	    }
4418 	  else
4419 	    elt_init = build_vec_init (build1 (INDIRECT_REF, type, base),
4420 				       0, init,
4421 				       explicit_value_init_p,
4422 				       0, complain);
4423 	}
4424       else if (explicit_value_init_p)
4425 	{
4426 	  elt_init = build_value_init (type, complain);
4427 	  if (elt_init != error_mark_node)
4428 	    elt_init = build2 (INIT_EXPR, type, to, elt_init);
4429 	}
4430       else
4431 	{
4432 	  gcc_assert (type_build_ctor_call (type) || init);
4433 	  if (CLASS_TYPE_P (type))
4434 	    elt_init = build_aggr_init (to, init, 0, complain);
4435 	  else
4436 	    {
4437 	      if (TREE_CODE (init) == TREE_LIST)
4438 		init = build_x_compound_expr_from_list (init, ELK_INIT,
4439 							complain);
4440 	      elt_init = (init == error_mark_node
4441 			  ? error_mark_node
4442 			  : build2 (INIT_EXPR, type, to, init));
4443 	    }
4444 	}
4445 
4446       if (elt_init == error_mark_node)
4447 	errors = true;
4448 
4449       if (try_const)
4450 	{
4451 	  /* FIXME refs to earlier elts */
4452 	  tree e = maybe_constant_init (elt_init);
4453 	  if (reduced_constant_expression_p (e))
4454 	    {
4455 	      if (initializer_zerop (e))
4456 		/* Don't fill the CONSTRUCTOR with zeros.  */
4457 		e = NULL_TREE;
4458 	      if (do_static_init)
4459 		elt_init = NULL_TREE;
4460 	    }
4461 	  else
4462 	    {
4463 	      saw_non_const = true;
4464 	      if (do_static_init)
4465 		e = build_zero_init (TREE_TYPE (e), NULL_TREE, true);
4466 	      else
4467 		e = NULL_TREE;
4468 	    }
4469 
4470 	  if (e)
4471 	    {
4472 	      HOST_WIDE_INT last = tree_to_shwi (maxindex);
4473 	      if (num_initialized_elts <= last)
4474 		{
4475 		  tree field = size_int (num_initialized_elts);
4476 		  if (num_initialized_elts != last)
4477 		    field = build2 (RANGE_EXPR, sizetype, field,
4478 				    size_int (last));
4479 		  CONSTRUCTOR_APPEND_ELT (const_vec, field, e);
4480 		}
4481 	    }
4482 	}
4483 
4484       current_stmt_tree ()->stmts_are_full_exprs_p = 1;
4485       if (elt_init && !errors)
4486 	finish_expr_stmt (elt_init);
4487       current_stmt_tree ()->stmts_are_full_exprs_p = 0;
4488 
4489       finish_expr_stmt (cp_build_unary_op (PREINCREMENT_EXPR, base, false,
4490                                            complain));
4491       if (base2)
4492 	finish_expr_stmt (cp_build_unary_op (PREINCREMENT_EXPR, base2, false,
4493                                              complain));
4494 
4495       finish_for_stmt (for_stmt);
4496     }
4497 
4498   /* Make sure to cleanup any partially constructed elements.  */
4499   if (flag_exceptions && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
4500       && from_array != 2)
4501     {
4502       tree e;
4503       tree m = cp_build_binary_op (input_location,
4504 				   MINUS_EXPR, maxindex, iterator,
4505 				   complain);
4506 
4507       /* Flatten multi-dimensional array since build_vec_delete only
4508 	 expects one-dimensional array.  */
4509       if (TREE_CODE (type) == ARRAY_TYPE)
4510 	m = cp_build_binary_op (input_location,
4511 				MULT_EXPR, m,
4512 				/* Avoid mixing signed and unsigned.  */
4513 				convert (TREE_TYPE (m),
4514 					 array_type_nelts_total (type)),
4515 				complain);
4516 
4517       finish_cleanup_try_block (try_block);
4518       e = build_vec_delete_1 (rval, m,
4519 			      inner_elt_type, sfk_complete_destructor,
4520 			      /*use_global_delete=*/0, complain);
4521       if (e == error_mark_node)
4522 	errors = true;
4523       finish_cleanup (e, try_block);
4524     }
4525 
4526   /* The value of the array initialization is the array itself, RVAL
4527      is a pointer to the first element.  */
4528   finish_stmt_expr_expr (rval, stmt_expr);
4529 
4530   stmt_expr = finish_init_stmts (is_global, stmt_expr, compound_stmt);
4531 
4532   current_stmt_tree ()->stmts_are_full_exprs_p = destroy_temps;
4533 
4534   if (errors)
4535     return error_mark_node;
4536 
4537   if (try_const)
4538     {
4539       if (!saw_non_const)
4540 	{
4541 	  tree const_init = build_constructor (atype, const_vec);
4542 	  return build2 (INIT_EXPR, atype, obase, const_init);
4543 	}
4544       else if (do_static_init && !vec_safe_is_empty (const_vec))
4545 	DECL_INITIAL (obase) = build_constructor (atype, const_vec);
4546       else
4547 	vec_free (const_vec);
4548     }
4549 
4550   /* Now make the result have the correct type.  */
4551   if (TREE_CODE (atype) == ARRAY_TYPE)
4552     {
4553       atype = build_pointer_type (atype);
4554       stmt_expr = build1 (NOP_EXPR, atype, stmt_expr);
4555       stmt_expr = cp_build_fold_indirect_ref (stmt_expr);
4556       TREE_NO_WARNING (stmt_expr) = 1;
4557     }
4558 
4559   return stmt_expr;
4560 }
4561 
4562 /* Call the DTOR_KIND destructor for EXP.  FLAGS are as for
4563    build_delete.  */
4564 
4565 static tree
build_dtor_call(tree exp,special_function_kind dtor_kind,int flags,tsubst_flags_t complain)4566 build_dtor_call (tree exp, special_function_kind dtor_kind, int flags,
4567 		 tsubst_flags_t complain)
4568 {
4569   tree name;
4570   tree fn;
4571   switch (dtor_kind)
4572     {
4573     case sfk_complete_destructor:
4574       name = complete_dtor_identifier;
4575       break;
4576 
4577     case sfk_base_destructor:
4578       name = base_dtor_identifier;
4579       break;
4580 
4581     case sfk_deleting_destructor:
4582       name = deleting_dtor_identifier;
4583       break;
4584 
4585     default:
4586       gcc_unreachable ();
4587     }
4588   fn = lookup_fnfields (TREE_TYPE (exp), name, /*protect=*/2);
4589   return build_new_method_call (exp, fn,
4590 				/*args=*/NULL,
4591 				/*conversion_path=*/NULL_TREE,
4592 				flags,
4593 				/*fn_p=*/NULL,
4594 				complain);
4595 }
4596 
4597 /* Generate a call to a destructor. TYPE is the type to cast ADDR to.
4598    ADDR is an expression which yields the store to be destroyed.
4599    AUTO_DELETE is the name of the destructor to call, i.e., either
4600    sfk_complete_destructor, sfk_base_destructor, or
4601    sfk_deleting_destructor.
4602 
4603    FLAGS is the logical disjunction of zero or more LOOKUP_
4604    flags.  See cp-tree.h for more info.  */
4605 
4606 tree
build_delete(tree otype,tree addr,special_function_kind auto_delete,int flags,int use_global_delete,tsubst_flags_t complain)4607 build_delete (tree otype, tree addr, special_function_kind auto_delete,
4608 	      int flags, int use_global_delete, tsubst_flags_t complain)
4609 {
4610   tree expr;
4611 
4612   if (addr == error_mark_node)
4613     return error_mark_node;
4614 
4615   tree type = TYPE_MAIN_VARIANT (otype);
4616 
4617   /* Can happen when CURRENT_EXCEPTION_OBJECT gets its type
4618      set to `error_mark_node' before it gets properly cleaned up.  */
4619   if (type == error_mark_node)
4620     return error_mark_node;
4621 
4622   if (TREE_CODE (type) == POINTER_TYPE)
4623     type = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4624 
4625   if (TREE_CODE (type) == ARRAY_TYPE)
4626     {
4627       if (TYPE_DOMAIN (type) == NULL_TREE)
4628 	{
4629 	  if (complain & tf_error)
4630 	    error ("unknown array size in delete");
4631 	  return error_mark_node;
4632 	}
4633       return build_vec_delete (addr, array_type_nelts (type),
4634 			       auto_delete, use_global_delete, complain);
4635     }
4636 
4637   if (TYPE_PTR_P (otype))
4638     {
4639       addr = mark_rvalue_use (addr);
4640 
4641       /* We don't want to warn about delete of void*, only other
4642 	  incomplete types.  Deleting other incomplete types
4643 	  invokes undefined behavior, but it is not ill-formed, so
4644 	  compile to something that would even do The Right Thing
4645 	  (TM) should the type have a trivial dtor and no delete
4646 	  operator.  */
4647       if (!VOID_TYPE_P (type))
4648 	{
4649 	  complete_type (type);
4650 	  if (!COMPLETE_TYPE_P (type))
4651 	    {
4652 	      if ((complain & tf_warning)
4653 		  && warning (OPT_Wdelete_incomplete,
4654 			      "possible problem detected in invocation of "
4655 			      "delete operator:"))
4656 		{
4657 		  cxx_incomplete_type_diagnostic (addr, type, DK_WARNING);
4658 		  inform (input_location,
4659 			  "neither the destructor nor the class-specific "
4660 			  "operator delete will be called, even if they are "
4661 			  "declared when the class is defined");
4662 		}
4663 	    }
4664 	  else if (auto_delete == sfk_deleting_destructor && warn_delnonvdtor
4665 	           && MAYBE_CLASS_TYPE_P (type) && !CLASSTYPE_FINAL (type)
4666 		   && TYPE_POLYMORPHIC_P (type))
4667 	    {
4668 	      tree dtor = CLASSTYPE_DESTRUCTOR (type);
4669 	      if (!dtor || !DECL_VINDEX (dtor))
4670 		{
4671 		  if (CLASSTYPE_PURE_VIRTUALS (type))
4672 		    warning (OPT_Wdelete_non_virtual_dtor,
4673 			     "deleting object of abstract class type %qT"
4674 			     " which has non-virtual destructor"
4675 			     " will cause undefined behavior", type);
4676 		  else
4677 		    warning (OPT_Wdelete_non_virtual_dtor,
4678 			     "deleting object of polymorphic class type %qT"
4679 			     " which has non-virtual destructor"
4680 			     " might cause undefined behavior", type);
4681 		}
4682 	    }
4683 	}
4684       if (TREE_SIDE_EFFECTS (addr))
4685 	addr = save_expr (addr);
4686 
4687       /* Throw away const and volatile on target type of addr.  */
4688       addr = convert_force (build_pointer_type (type), addr, 0, complain);
4689     }
4690   else
4691     {
4692       /* Don't check PROTECT here; leave that decision to the
4693 	 destructor.  If the destructor is accessible, call it,
4694 	 else report error.  */
4695       addr = cp_build_addr_expr (addr, complain);
4696       if (addr == error_mark_node)
4697 	return error_mark_node;
4698       if (TREE_SIDE_EFFECTS (addr))
4699 	addr = save_expr (addr);
4700 
4701       addr = convert_force (build_pointer_type (type), addr, 0, complain);
4702     }
4703 
4704   if (TYPE_HAS_TRIVIAL_DESTRUCTOR (type))
4705     {
4706       /* Make sure the destructor is callable.  */
4707       if (type_build_dtor_call (type))
4708 	{
4709 	  expr = build_dtor_call (cp_build_fold_indirect_ref (addr),
4710 				  sfk_complete_destructor, flags, complain);
4711 	  if (expr == error_mark_node)
4712 	    return error_mark_node;
4713 	}
4714 
4715       if (auto_delete != sfk_deleting_destructor)
4716 	return void_node;
4717 
4718       return build_op_delete_call (DELETE_EXPR, addr,
4719 				   cxx_sizeof_nowarn (type),
4720 				   use_global_delete,
4721 				   /*placement=*/NULL_TREE,
4722 				   /*alloc_fn=*/NULL_TREE,
4723 				   complain);
4724     }
4725   else
4726     {
4727       tree head = NULL_TREE;
4728       tree do_delete = NULL_TREE;
4729       tree ifexp;
4730 
4731       if (CLASSTYPE_LAZY_DESTRUCTOR (type))
4732 	lazily_declare_fn (sfk_destructor, type);
4733 
4734       /* For `::delete x', we must not use the deleting destructor
4735 	 since then we would not be sure to get the global `operator
4736 	 delete'.  */
4737       if (use_global_delete && auto_delete == sfk_deleting_destructor)
4738 	{
4739 	  /* We will use ADDR multiple times so we must save it.  */
4740 	  addr = save_expr (addr);
4741 	  head = get_target_expr (build_headof (addr));
4742 	  /* Delete the object.  */
4743 	  do_delete = build_op_delete_call (DELETE_EXPR,
4744 					    head,
4745 					    cxx_sizeof_nowarn (type),
4746 					    /*global_p=*/true,
4747 					    /*placement=*/NULL_TREE,
4748 					    /*alloc_fn=*/NULL_TREE,
4749 					    complain);
4750 	  /* Otherwise, treat this like a complete object destructor
4751 	     call.  */
4752 	  auto_delete = sfk_complete_destructor;
4753 	}
4754       /* If the destructor is non-virtual, there is no deleting
4755 	 variant.  Instead, we must explicitly call the appropriate
4756 	 `operator delete' here.  */
4757       else if (!DECL_VIRTUAL_P (CLASSTYPE_DESTRUCTOR (type))
4758 	       && auto_delete == sfk_deleting_destructor)
4759 	{
4760 	  /* We will use ADDR multiple times so we must save it.  */
4761 	  addr = save_expr (addr);
4762 	  /* Build the call.  */
4763 	  do_delete = build_op_delete_call (DELETE_EXPR,
4764 					    addr,
4765 					    cxx_sizeof_nowarn (type),
4766 					    /*global_p=*/false,
4767 					    /*placement=*/NULL_TREE,
4768 					    /*alloc_fn=*/NULL_TREE,
4769 					    complain);
4770 	  /* Call the complete object destructor.  */
4771 	  auto_delete = sfk_complete_destructor;
4772 	}
4773       else if (auto_delete == sfk_deleting_destructor
4774 	       && TYPE_GETS_REG_DELETE (type))
4775 	{
4776 	  /* Make sure we have access to the member op delete, even though
4777 	     we'll actually be calling it from the destructor.  */
4778 	  build_op_delete_call (DELETE_EXPR, addr, cxx_sizeof_nowarn (type),
4779 				/*global_p=*/false,
4780 				/*placement=*/NULL_TREE,
4781 				/*alloc_fn=*/NULL_TREE,
4782 				complain);
4783 	}
4784 
4785       expr = build_dtor_call (cp_build_fold_indirect_ref (addr),
4786 			      auto_delete, flags, complain);
4787       if (expr == error_mark_node)
4788 	return error_mark_node;
4789       if (do_delete)
4790 	/* The delete operator must be called, regardless of whether
4791 	   the destructor throws.
4792 
4793 	   [expr.delete]/7 The deallocation function is called
4794 	   regardless of whether the destructor for the object or some
4795 	   element of the array throws an exception.  */
4796 	expr = build2 (TRY_FINALLY_EXPR, void_type_node, expr, do_delete);
4797 
4798       /* We need to calculate this before the dtor changes the vptr.  */
4799       if (head)
4800 	expr = build2 (COMPOUND_EXPR, void_type_node, head, expr);
4801 
4802       if (flags & LOOKUP_DESTRUCTOR)
4803 	/* Explicit destructor call; don't check for null pointer.  */
4804 	ifexp = integer_one_node;
4805       else
4806 	{
4807 	  /* Handle deleting a null pointer.  */
4808 	  warning_sentinel s (warn_address);
4809 	  ifexp = cp_build_binary_op (input_location, NE_EXPR, addr,
4810 				      nullptr_node, complain);
4811 	  if (ifexp == error_mark_node)
4812 	    return error_mark_node;
4813 	  /* This is a compiler generated comparison, don't emit
4814 	     e.g. -Wnonnull-compare warning for it.  */
4815 	  else if (TREE_CODE (ifexp) == NE_EXPR)
4816 	    TREE_NO_WARNING (ifexp) = 1;
4817 	}
4818 
4819       if (ifexp != integer_one_node)
4820 	expr = build3 (COND_EXPR, void_type_node, ifexp, expr, void_node);
4821 
4822       return expr;
4823     }
4824 }
4825 
4826 /* At the beginning of a destructor, push cleanups that will call the
4827    destructors for our base classes and members.
4828 
4829    Called from begin_destructor_body.  */
4830 
4831 void
push_base_cleanups(void)4832 push_base_cleanups (void)
4833 {
4834   tree binfo, base_binfo;
4835   int i;
4836   tree member;
4837   tree expr;
4838   vec<tree, va_gc> *vbases;
4839 
4840   /* Run destructors for all virtual baseclasses.  */
4841   if (!ABSTRACT_CLASS_TYPE_P (current_class_type)
4842       && CLASSTYPE_VBASECLASSES (current_class_type))
4843     {
4844       tree cond = (condition_conversion
4845 		   (build2 (BIT_AND_EXPR, integer_type_node,
4846 			    current_in_charge_parm,
4847 			    integer_two_node)));
4848 
4849       /* The CLASSTYPE_VBASECLASSES vector is in initialization
4850 	 order, which is also the right order for pushing cleanups.  */
4851       for (vbases = CLASSTYPE_VBASECLASSES (current_class_type), i = 0;
4852 	   vec_safe_iterate (vbases, i, &base_binfo); i++)
4853 	{
4854 	  if (type_build_dtor_call (BINFO_TYPE (base_binfo)))
4855 	    {
4856 	      expr = build_special_member_call (current_class_ref,
4857 						base_dtor_identifier,
4858 						NULL,
4859 						base_binfo,
4860 						(LOOKUP_NORMAL
4861 						 | LOOKUP_NONVIRTUAL),
4862 						tf_warning_or_error);
4863 	      if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (BINFO_TYPE (base_binfo)))
4864 		{
4865 		  expr = build3 (COND_EXPR, void_type_node, cond,
4866 				 expr, void_node);
4867 		  finish_decl_cleanup (NULL_TREE, expr);
4868 		}
4869 	    }
4870 	}
4871     }
4872 
4873   /* Take care of the remaining baseclasses.  */
4874   for (binfo = TYPE_BINFO (current_class_type), i = 0;
4875        BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
4876     {
4877       if (BINFO_VIRTUAL_P (base_binfo)
4878 	  || !type_build_dtor_call (BINFO_TYPE (base_binfo)))
4879 	continue;
4880 
4881       expr = build_special_member_call (current_class_ref,
4882 					base_dtor_identifier,
4883 					NULL, base_binfo,
4884 					LOOKUP_NORMAL | LOOKUP_NONVIRTUAL,
4885                                         tf_warning_or_error);
4886       if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (BINFO_TYPE (base_binfo)))
4887 	finish_decl_cleanup (NULL_TREE, expr);
4888     }
4889 
4890   /* Don't automatically destroy union members.  */
4891   if (TREE_CODE (current_class_type) == UNION_TYPE)
4892     return;
4893 
4894   for (member = TYPE_FIELDS (current_class_type); member;
4895        member = DECL_CHAIN (member))
4896     {
4897       tree this_type = TREE_TYPE (member);
4898       if (this_type == error_mark_node
4899 	  || TREE_CODE (member) != FIELD_DECL
4900 	  || DECL_ARTIFICIAL (member))
4901 	continue;
4902       if (ANON_AGGR_TYPE_P (this_type))
4903 	continue;
4904       if (type_build_dtor_call (this_type))
4905 	{
4906 	  tree this_member = (build_class_member_access_expr
4907 			      (current_class_ref, member,
4908 			       /*access_path=*/NULL_TREE,
4909 			       /*preserve_reference=*/false,
4910 			       tf_warning_or_error));
4911 	  expr = build_delete (this_type, this_member,
4912 			       sfk_complete_destructor,
4913 			       LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR|LOOKUP_NORMAL,
4914 			       0, tf_warning_or_error);
4915 	  if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (this_type))
4916 	    finish_decl_cleanup (NULL_TREE, expr);
4917 	}
4918     }
4919 }
4920 
4921 /* Build a C++ vector delete expression.
4922    MAXINDEX is the number of elements to be deleted.
4923    ELT_SIZE is the nominal size of each element in the vector.
4924    BASE is the expression that should yield the store to be deleted.
4925    This function expands (or synthesizes) these calls itself.
4926    AUTO_DELETE_VEC says whether the container (vector) should be deallocated.
4927 
4928    This also calls delete for virtual baseclasses of elements of the vector.
4929 
4930    Update: MAXINDEX is no longer needed.  The size can be extracted from the
4931    start of the vector for pointers, and from the type for arrays.  We still
4932    use MAXINDEX for arrays because it happens to already have one of the
4933    values we'd have to extract.  (We could use MAXINDEX with pointers to
4934    confirm the size, and trap if the numbers differ; not clear that it'd
4935    be worth bothering.)  */
4936 
4937 tree
build_vec_delete(tree base,tree maxindex,special_function_kind auto_delete_vec,int use_global_delete,tsubst_flags_t complain)4938 build_vec_delete (tree base, tree maxindex,
4939 		  special_function_kind auto_delete_vec,
4940 		  int use_global_delete, tsubst_flags_t complain)
4941 {
4942   tree type;
4943   tree rval;
4944   tree base_init = NULL_TREE;
4945 
4946   type = TREE_TYPE (base);
4947 
4948   if (TYPE_PTR_P (type))
4949     {
4950       /* Step back one from start of vector, and read dimension.  */
4951       tree cookie_addr;
4952       tree size_ptr_type = build_pointer_type (sizetype);
4953 
4954       base = mark_rvalue_use (base);
4955       if (TREE_SIDE_EFFECTS (base))
4956 	{
4957 	  base_init = get_target_expr (base);
4958 	  base = TARGET_EXPR_SLOT (base_init);
4959 	}
4960       type = strip_array_types (TREE_TYPE (type));
4961       cookie_addr = fold_build1_loc (input_location, NEGATE_EXPR,
4962 				 sizetype, TYPE_SIZE_UNIT (sizetype));
4963       cookie_addr = fold_build_pointer_plus (fold_convert (size_ptr_type, base),
4964 					     cookie_addr);
4965       maxindex = cp_build_fold_indirect_ref (cookie_addr);
4966     }
4967   else if (TREE_CODE (type) == ARRAY_TYPE)
4968     {
4969       /* Get the total number of things in the array, maxindex is a
4970 	 bad name.  */
4971       maxindex = array_type_nelts_total (type);
4972       type = strip_array_types (type);
4973       base = decay_conversion (base, complain);
4974       if (base == error_mark_node)
4975 	return error_mark_node;
4976       if (TREE_SIDE_EFFECTS (base))
4977 	{
4978 	  base_init = get_target_expr (base);
4979 	  base = TARGET_EXPR_SLOT (base_init);
4980 	}
4981     }
4982   else
4983     {
4984       if (base != error_mark_node && !(complain & tf_error))
4985 	error ("type to vector delete is neither pointer or array type");
4986       return error_mark_node;
4987     }
4988 
4989   rval = build_vec_delete_1 (base, maxindex, type, auto_delete_vec,
4990 			     use_global_delete, complain);
4991   if (base_init && rval != error_mark_node)
4992     rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), base_init, rval);
4993 
4994   return rval;
4995 }
4996 
4997 #include "gt-cp-init.h"
4998