1 /* Handle initialization things in C++.
2 Copyright (C) 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4 Contributed by Michael Tiemann (tiemann@cygnus.com)
5
6 This file is part of GCC.
7
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
11 any later version.
12
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to
20 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
22
23 /* High-level class interface. */
24
25 #include "config.h"
26 #include "system.h"
27 #include "coretypes.h"
28 #include "tm.h"
29 #include "tree.h"
30 #include "rtl.h"
31 #include "expr.h"
32 #include "cp-tree.h"
33 #include "flags.h"
34 #include "output.h"
35 #include "except.h"
36 #include "toplev.h"
37 #include "target.h"
38
39 static bool begin_init_stmts (tree *, tree *);
40 static tree finish_init_stmts (bool, tree, tree);
41 static void construct_virtual_base (tree, tree);
42 static void expand_aggr_init_1 (tree, tree, tree, tree, int);
43 static void expand_default_init (tree, tree, tree, tree, int);
44 static tree build_vec_delete_1 (tree, tree, tree, special_function_kind, int);
45 static void perform_member_init (tree, tree);
46 static tree build_builtin_delete_call (tree);
47 static int member_init_ok_or_else (tree, tree, tree);
48 static void expand_virtual_init (tree, tree);
49 static tree sort_mem_initializers (tree, tree);
50 static tree initializing_context (tree);
51 static void expand_cleanup_for_base (tree, tree);
52 static tree get_temp_regvar (tree, tree);
53 static tree dfs_initialize_vtbl_ptrs (tree, void *);
54 static tree build_default_init (tree, tree);
55 static tree build_dtor_call (tree, special_function_kind, int);
56 static tree build_field_list (tree, tree, int *);
57 static tree build_vtbl_address (tree);
58
59 /* We are about to generate some complex initialization code.
60 Conceptually, it is all a single expression. However, we may want
61 to include conditionals, loops, and other such statement-level
62 constructs. Therefore, we build the initialization code inside a
63 statement-expression. This function starts such an expression.
64 STMT_EXPR_P and COMPOUND_STMT_P are filled in by this function;
65 pass them back to finish_init_stmts when the expression is
66 complete. */
67
68 static bool
begin_init_stmts(tree * stmt_expr_p,tree * compound_stmt_p)69 begin_init_stmts (tree *stmt_expr_p, tree *compound_stmt_p)
70 {
71 bool is_global = !building_stmt_tree ();
72
73 *stmt_expr_p = begin_stmt_expr ();
74 *compound_stmt_p = begin_compound_stmt (BCS_NO_SCOPE);
75
76 return is_global;
77 }
78
79 /* Finish out the statement-expression begun by the previous call to
80 begin_init_stmts. Returns the statement-expression itself. */
81
82 static tree
finish_init_stmts(bool is_global,tree stmt_expr,tree compound_stmt)83 finish_init_stmts (bool is_global, tree stmt_expr, tree compound_stmt)
84 {
85 finish_compound_stmt (compound_stmt);
86
87 stmt_expr = finish_stmt_expr (stmt_expr, true);
88
89 gcc_assert (!building_stmt_tree () == is_global);
90
91 return stmt_expr;
92 }
93
94 /* Constructors */
95
96 /* Called from initialize_vtbl_ptrs via dfs_walk. BINFO is the base
97 which we want to initialize the vtable pointer for, DATA is
98 TREE_LIST whose TREE_VALUE is the this ptr expression. */
99
100 static tree
dfs_initialize_vtbl_ptrs(tree binfo,void * data)101 dfs_initialize_vtbl_ptrs (tree binfo, void *data)
102 {
103 if (!TYPE_CONTAINS_VPTR_P (BINFO_TYPE (binfo)))
104 return dfs_skip_bases;
105
106 if (!BINFO_PRIMARY_P (binfo) || BINFO_VIRTUAL_P (binfo))
107 {
108 tree base_ptr = TREE_VALUE ((tree) data);
109
110 base_ptr = build_base_path (PLUS_EXPR, base_ptr, binfo, /*nonnull=*/1);
111
112 expand_virtual_init (binfo, base_ptr);
113 }
114
115 return NULL_TREE;
116 }
117
118 /* Initialize all the vtable pointers in the object pointed to by
119 ADDR. */
120
121 void
initialize_vtbl_ptrs(tree addr)122 initialize_vtbl_ptrs (tree addr)
123 {
124 tree list;
125 tree type;
126
127 type = TREE_TYPE (TREE_TYPE (addr));
128 list = build_tree_list (type, addr);
129
130 /* Walk through the hierarchy, initializing the vptr in each base
131 class. We do these in pre-order because we can't find the virtual
132 bases for a class until we've initialized the vtbl for that
133 class. */
134 dfs_walk_once (TYPE_BINFO (type), dfs_initialize_vtbl_ptrs, NULL, list);
135 }
136
137 /* Return an expression for the zero-initialization of an object with
138 type T. This expression will either be a constant (in the case
139 that T is a scalar), or a CONSTRUCTOR (in the case that T is an
140 aggregate). In either case, the value can be used as DECL_INITIAL
141 for a decl of the indicated TYPE; it is a valid static initializer.
142 If NELTS is non-NULL, and TYPE is an ARRAY_TYPE, NELTS is the
143 number of elements in the array. If STATIC_STORAGE_P is TRUE,
144 initializers are only generated for entities for which
145 zero-initialization does not simply mean filling the storage with
146 zero bytes. */
147
148 tree
build_zero_init(tree type,tree nelts,bool static_storage_p)149 build_zero_init (tree type, tree nelts, bool static_storage_p)
150 {
151 tree init = NULL_TREE;
152
153 /* [dcl.init]
154
155 To zero-initialization storage for an object of type T means:
156
157 -- if T is a scalar type, the storage is set to the value of zero
158 converted to T.
159
160 -- if T is a non-union class type, the storage for each nonstatic
161 data member and each base-class subobject is zero-initialized.
162
163 -- if T is a union type, the storage for its first data member is
164 zero-initialized.
165
166 -- if T is an array type, the storage for each element is
167 zero-initialized.
168
169 -- if T is a reference type, no initialization is performed. */
170
171 gcc_assert (nelts == NULL_TREE || TREE_CODE (nelts) == INTEGER_CST);
172
173 if (type == error_mark_node)
174 ;
175 else if (static_storage_p && zero_init_p (type))
176 /* In order to save space, we do not explicitly build initializers
177 for items that do not need them. GCC's semantics are that
178 items with static storage duration that are not otherwise
179 initialized are initialized to zero. */
180 ;
181 else if (SCALAR_TYPE_P (type))
182 init = convert (type, integer_zero_node);
183 else if (CLASS_TYPE_P (type))
184 {
185 tree field;
186 VEC(constructor_elt,gc) *v = NULL;
187
188 /* Iterate over the fields, building initializations. */
189 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
190 {
191 if (TREE_CODE (field) != FIELD_DECL)
192 continue;
193
194 /* Note that for class types there will be FIELD_DECLs
195 corresponding to base classes as well. Thus, iterating
196 over TYPE_FIELDs will result in correct initialization of
197 all of the subobjects. */
198 if (!static_storage_p || !zero_init_p (TREE_TYPE (field)))
199 {
200 tree value = build_zero_init (TREE_TYPE (field),
201 /*nelts=*/NULL_TREE,
202 static_storage_p);
203 CONSTRUCTOR_APPEND_ELT(v, field, value);
204 }
205
206 /* For unions, only the first field is initialized. */
207 if (TREE_CODE (type) == UNION_TYPE)
208 break;
209 }
210
211 /* Build a constructor to contain the initializations. */
212 init = build_constructor (type, v);
213 }
214 else if (TREE_CODE (type) == ARRAY_TYPE)
215 {
216 tree max_index;
217 VEC(constructor_elt,gc) *v = NULL;
218
219 /* Iterate over the array elements, building initializations. */
220 if (nelts)
221 max_index = fold_build2 (MINUS_EXPR, TREE_TYPE (nelts),
222 nelts, integer_one_node);
223 else
224 max_index = array_type_nelts (type);
225
226 /* If we have an error_mark here, we should just return error mark
227 as we don't know the size of the array yet. */
228 if (max_index == error_mark_node)
229 return error_mark_node;
230 gcc_assert (TREE_CODE (max_index) == INTEGER_CST);
231
232 /* A zero-sized array, which is accepted as an extension, will
233 have an upper bound of -1. */
234 if (!tree_int_cst_equal (max_index, integer_minus_one_node))
235 {
236 constructor_elt *ce;
237
238 v = VEC_alloc (constructor_elt, gc, 1);
239 ce = VEC_quick_push (constructor_elt, v, NULL);
240
241 /* If this is a one element array, we just use a regular init. */
242 if (tree_int_cst_equal (size_zero_node, max_index))
243 ce->index = size_zero_node;
244 else
245 ce->index = build2 (RANGE_EXPR, sizetype, size_zero_node,
246 max_index);
247
248 ce->value = build_zero_init (TREE_TYPE (type),
249 /*nelts=*/NULL_TREE,
250 static_storage_p);
251 }
252
253 /* Build a constructor to contain the initializations. */
254 init = build_constructor (type, v);
255 }
256 else if (TREE_CODE (type) == VECTOR_TYPE)
257 init = fold_convert (type, integer_zero_node);
258 else
259 gcc_assert (TREE_CODE (type) == REFERENCE_TYPE);
260
261 /* In all cases, the initializer is a constant. */
262 if (init)
263 {
264 TREE_CONSTANT (init) = 1;
265 TREE_INVARIANT (init) = 1;
266 }
267
268 return init;
269 }
270
271 /* Build an expression for the default-initialization of an object of
272 the indicated TYPE. If NELTS is non-NULL, and TYPE is an
273 ARRAY_TYPE, NELTS is the number of elements in the array. If
274 initialization of TYPE requires calling constructors, this function
275 returns NULL_TREE; the caller is responsible for arranging for the
276 constructors to be called. */
277
278 static tree
build_default_init(tree type,tree nelts)279 build_default_init (tree type, tree nelts)
280 {
281 /* [dcl.init]:
282
283 To default-initialize an object of type T means:
284
285 --if T is a non-POD class type (clause _class_), the default construc-
286 tor for T is called (and the initialization is ill-formed if T has
287 no accessible default constructor);
288
289 --if T is an array type, each element is default-initialized;
290
291 --otherwise, the storage for the object is zero-initialized.
292
293 A program that calls for default-initialization of an entity of refer-
294 ence type is ill-formed. */
295
296 /* If TYPE_NEEDS_CONSTRUCTING is true, the caller is responsible for
297 performing the initialization. This is confusing in that some
298 non-PODs do not have TYPE_NEEDS_CONSTRUCTING set. (For example,
299 a class with a pointer-to-data member as a non-static data member
300 does not have TYPE_NEEDS_CONSTRUCTING set.) Therefore, we end up
301 passing non-PODs to build_zero_init below, which is contrary to
302 the semantics quoted above from [dcl.init].
303
304 It happens, however, that the behavior of the constructor the
305 standard says we should have generated would be precisely the
306 same as that obtained by calling build_zero_init below, so things
307 work out OK. */
308 if (TYPE_NEEDS_CONSTRUCTING (type)
309 || (nelts && TREE_CODE (nelts) != INTEGER_CST))
310 return NULL_TREE;
311
312 /* At this point, TYPE is either a POD class type, an array of POD
313 classes, or something even more innocuous. */
314 return build_zero_init (type, nelts, /*static_storage_p=*/false);
315 }
316
317 /* Initialize MEMBER, a FIELD_DECL, with INIT, a TREE_LIST of
318 arguments. If TREE_LIST is void_type_node, an empty initializer
319 list was given; if NULL_TREE no initializer was given. */
320
321 static void
perform_member_init(tree member,tree init)322 perform_member_init (tree member, tree init)
323 {
324 tree decl;
325 tree type = TREE_TYPE (member);
326 bool explicit;
327
328 explicit = (init != NULL_TREE);
329
330 /* Effective C++ rule 12 requires that all data members be
331 initialized. */
332 if (warn_ecpp && !explicit && TREE_CODE (type) != ARRAY_TYPE)
333 warning (OPT_Weffc__, "%J%qD should be initialized in the member initialization "
334 "list", current_function_decl, member);
335
336 if (init == void_type_node)
337 init = NULL_TREE;
338
339 /* Get an lvalue for the data member. */
340 decl = build_class_member_access_expr (current_class_ref, member,
341 /*access_path=*/NULL_TREE,
342 /*preserve_reference=*/true);
343 if (decl == error_mark_node)
344 return;
345
346 /* Deal with this here, as we will get confused if we try to call the
347 assignment op for an anonymous union. This can happen in a
348 synthesized copy constructor. */
349 if (ANON_AGGR_TYPE_P (type))
350 {
351 if (init)
352 {
353 init = build2 (INIT_EXPR, type, decl, TREE_VALUE (init));
354 finish_expr_stmt (init);
355 }
356 }
357 else if (TYPE_NEEDS_CONSTRUCTING (type))
358 {
359 if (explicit
360 && TREE_CODE (type) == ARRAY_TYPE
361 && init != NULL_TREE
362 && TREE_CHAIN (init) == NULL_TREE
363 && TREE_CODE (TREE_TYPE (TREE_VALUE (init))) == ARRAY_TYPE)
364 {
365 /* Initialization of one array from another. */
366 finish_expr_stmt (build_vec_init (decl, NULL_TREE, TREE_VALUE (init),
367 /*explicit_default_init_p=*/false,
368 /* from_array=*/1));
369 }
370 else
371 finish_expr_stmt (build_aggr_init (decl, init, 0));
372 }
373 else
374 {
375 if (init == NULL_TREE)
376 {
377 if (explicit)
378 {
379 init = build_default_init (type, /*nelts=*/NULL_TREE);
380 if (TREE_CODE (type) == REFERENCE_TYPE)
381 warning (0, "%Jdefault-initialization of %q#D, "
382 "which has reference type",
383 current_function_decl, member);
384 }
385 /* member traversal: note it leaves init NULL */
386 else if (TREE_CODE (type) == REFERENCE_TYPE)
387 pedwarn ("%Juninitialized reference member %qD",
388 current_function_decl, member);
389 else if (CP_TYPE_CONST_P (type))
390 pedwarn ("%Juninitialized member %qD with %<const%> type %qT",
391 current_function_decl, member, type);
392 }
393 else if (TREE_CODE (init) == TREE_LIST)
394 /* There was an explicit member initialization. Do some work
395 in that case. */
396 init = build_x_compound_expr_from_list (init, "member initializer");
397
398 if (init)
399 finish_expr_stmt (build_modify_expr (decl, INIT_EXPR, init));
400 }
401
402 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type))
403 {
404 tree expr;
405
406 expr = build_class_member_access_expr (current_class_ref, member,
407 /*access_path=*/NULL_TREE,
408 /*preserve_reference=*/false);
409 expr = build_delete (type, expr, sfk_complete_destructor,
410 LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR, 0);
411
412 if (expr != error_mark_node)
413 finish_eh_cleanup (expr);
414 }
415 }
416
417 /* Returns a TREE_LIST containing (as the TREE_PURPOSE of each node) all
418 the FIELD_DECLs on the TYPE_FIELDS list for T, in reverse order. */
419
420 static tree
build_field_list(tree t,tree list,int * uses_unions_p)421 build_field_list (tree t, tree list, int *uses_unions_p)
422 {
423 tree fields;
424
425 *uses_unions_p = 0;
426
427 /* Note whether or not T is a union. */
428 if (TREE_CODE (t) == UNION_TYPE)
429 *uses_unions_p = 1;
430
431 for (fields = TYPE_FIELDS (t); fields; fields = TREE_CHAIN (fields))
432 {
433 /* Skip CONST_DECLs for enumeration constants and so forth. */
434 if (TREE_CODE (fields) != FIELD_DECL || DECL_ARTIFICIAL (fields))
435 continue;
436
437 /* Keep track of whether or not any fields are unions. */
438 if (TREE_CODE (TREE_TYPE (fields)) == UNION_TYPE)
439 *uses_unions_p = 1;
440
441 /* For an anonymous struct or union, we must recursively
442 consider the fields of the anonymous type. They can be
443 directly initialized from the constructor. */
444 if (ANON_AGGR_TYPE_P (TREE_TYPE (fields)))
445 {
446 /* Add this field itself. Synthesized copy constructors
447 initialize the entire aggregate. */
448 list = tree_cons (fields, NULL_TREE, list);
449 /* And now add the fields in the anonymous aggregate. */
450 list = build_field_list (TREE_TYPE (fields), list,
451 uses_unions_p);
452 }
453 /* Add this field. */
454 else if (DECL_NAME (fields))
455 list = tree_cons (fields, NULL_TREE, list);
456 }
457
458 return list;
459 }
460
461 /* The MEM_INITS are a TREE_LIST. The TREE_PURPOSE of each list gives
462 a FIELD_DECL or BINFO in T that needs initialization. The
463 TREE_VALUE gives the initializer, or list of initializer arguments.
464
465 Return a TREE_LIST containing all of the initializations required
466 for T, in the order in which they should be performed. The output
467 list has the same format as the input. */
468
469 static tree
sort_mem_initializers(tree t,tree mem_inits)470 sort_mem_initializers (tree t, tree mem_inits)
471 {
472 tree init;
473 tree base, binfo, base_binfo;
474 tree sorted_inits;
475 tree next_subobject;
476 VEC(tree,gc) *vbases;
477 int i;
478 int uses_unions_p;
479
480 /* Build up a list of initializations. The TREE_PURPOSE of entry
481 will be the subobject (a FIELD_DECL or BINFO) to initialize. The
482 TREE_VALUE will be the constructor arguments, or NULL if no
483 explicit initialization was provided. */
484 sorted_inits = NULL_TREE;
485
486 /* Process the virtual bases. */
487 for (vbases = CLASSTYPE_VBASECLASSES (t), i = 0;
488 VEC_iterate (tree, vbases, i, base); i++)
489 sorted_inits = tree_cons (base, NULL_TREE, sorted_inits);
490
491 /* Process the direct bases. */
492 for (binfo = TYPE_BINFO (t), i = 0;
493 BINFO_BASE_ITERATE (binfo, i, base_binfo); ++i)
494 if (!BINFO_VIRTUAL_P (base_binfo))
495 sorted_inits = tree_cons (base_binfo, NULL_TREE, sorted_inits);
496
497 /* Process the non-static data members. */
498 sorted_inits = build_field_list (t, sorted_inits, &uses_unions_p);
499 /* Reverse the entire list of initializations, so that they are in
500 the order that they will actually be performed. */
501 sorted_inits = nreverse (sorted_inits);
502
503 /* If the user presented the initializers in an order different from
504 that in which they will actually occur, we issue a warning. Keep
505 track of the next subobject which can be explicitly initialized
506 without issuing a warning. */
507 next_subobject = sorted_inits;
508
509 /* Go through the explicit initializers, filling in TREE_PURPOSE in
510 the SORTED_INITS. */
511 for (init = mem_inits; init; init = TREE_CHAIN (init))
512 {
513 tree subobject;
514 tree subobject_init;
515
516 subobject = TREE_PURPOSE (init);
517
518 /* If the explicit initializers are in sorted order, then
519 SUBOBJECT will be NEXT_SUBOBJECT, or something following
520 it. */
521 for (subobject_init = next_subobject;
522 subobject_init;
523 subobject_init = TREE_CHAIN (subobject_init))
524 if (TREE_PURPOSE (subobject_init) == subobject)
525 break;
526
527 /* Issue a warning if the explicit initializer order does not
528 match that which will actually occur.
529 ??? Are all these on the correct lines? */
530 if (warn_reorder && !subobject_init)
531 {
532 if (TREE_CODE (TREE_PURPOSE (next_subobject)) == FIELD_DECL)
533 warning (OPT_Wreorder, "%q+D will be initialized after",
534 TREE_PURPOSE (next_subobject));
535 else
536 warning (OPT_Wreorder, "base %qT will be initialized after",
537 TREE_PURPOSE (next_subobject));
538 if (TREE_CODE (subobject) == FIELD_DECL)
539 warning (OPT_Wreorder, " %q+#D", subobject);
540 else
541 warning (OPT_Wreorder, " base %qT", subobject);
542 warning (OPT_Wreorder, "%J when initialized here", current_function_decl);
543 }
544
545 /* Look again, from the beginning of the list. */
546 if (!subobject_init)
547 {
548 subobject_init = sorted_inits;
549 while (TREE_PURPOSE (subobject_init) != subobject)
550 subobject_init = TREE_CHAIN (subobject_init);
551 }
552
553 /* It is invalid to initialize the same subobject more than
554 once. */
555 if (TREE_VALUE (subobject_init))
556 {
557 if (TREE_CODE (subobject) == FIELD_DECL)
558 error ("%Jmultiple initializations given for %qD",
559 current_function_decl, subobject);
560 else
561 error ("%Jmultiple initializations given for base %qT",
562 current_function_decl, subobject);
563 }
564
565 /* Record the initialization. */
566 TREE_VALUE (subobject_init) = TREE_VALUE (init);
567 next_subobject = subobject_init;
568 }
569
570 /* [class.base.init]
571
572 If a ctor-initializer specifies more than one mem-initializer for
573 multiple members of the same union (including members of
574 anonymous unions), the ctor-initializer is ill-formed. */
575 if (uses_unions_p)
576 {
577 tree last_field = NULL_TREE;
578 for (init = sorted_inits; init; init = TREE_CHAIN (init))
579 {
580 tree field;
581 tree field_type;
582 int done;
583
584 /* Skip uninitialized members and base classes. */
585 if (!TREE_VALUE (init)
586 || TREE_CODE (TREE_PURPOSE (init)) != FIELD_DECL)
587 continue;
588 /* See if this field is a member of a union, or a member of a
589 structure contained in a union, etc. */
590 field = TREE_PURPOSE (init);
591 for (field_type = DECL_CONTEXT (field);
592 !same_type_p (field_type, t);
593 field_type = TYPE_CONTEXT (field_type))
594 if (TREE_CODE (field_type) == UNION_TYPE)
595 break;
596 /* If this field is not a member of a union, skip it. */
597 if (TREE_CODE (field_type) != UNION_TYPE)
598 continue;
599
600 /* It's only an error if we have two initializers for the same
601 union type. */
602 if (!last_field)
603 {
604 last_field = field;
605 continue;
606 }
607
608 /* See if LAST_FIELD and the field initialized by INIT are
609 members of the same union. If so, there's a problem,
610 unless they're actually members of the same structure
611 which is itself a member of a union. For example, given:
612
613 union { struct { int i; int j; }; };
614
615 initializing both `i' and `j' makes sense. */
616 field_type = DECL_CONTEXT (field);
617 done = 0;
618 do
619 {
620 tree last_field_type;
621
622 last_field_type = DECL_CONTEXT (last_field);
623 while (1)
624 {
625 if (same_type_p (last_field_type, field_type))
626 {
627 if (TREE_CODE (field_type) == UNION_TYPE)
628 error ("%Jinitializations for multiple members of %qT",
629 current_function_decl, last_field_type);
630 done = 1;
631 break;
632 }
633
634 if (same_type_p (last_field_type, t))
635 break;
636
637 last_field_type = TYPE_CONTEXT (last_field_type);
638 }
639
640 /* If we've reached the outermost class, then we're
641 done. */
642 if (same_type_p (field_type, t))
643 break;
644
645 field_type = TYPE_CONTEXT (field_type);
646 }
647 while (!done);
648
649 last_field = field;
650 }
651 }
652
653 return sorted_inits;
654 }
655
656 /* Initialize all bases and members of CURRENT_CLASS_TYPE. MEM_INITS
657 is a TREE_LIST giving the explicit mem-initializer-list for the
658 constructor. The TREE_PURPOSE of each entry is a subobject (a
659 FIELD_DECL or a BINFO) of the CURRENT_CLASS_TYPE. The TREE_VALUE
660 is a TREE_LIST giving the arguments to the constructor or
661 void_type_node for an empty list of arguments. */
662
663 void
emit_mem_initializers(tree mem_inits)664 emit_mem_initializers (tree mem_inits)
665 {
666 /* We will already have issued an error message about the fact that
667 the type is incomplete. */
668 if (!COMPLETE_TYPE_P (current_class_type))
669 return;
670
671 /* Sort the mem-initializers into the order in which the
672 initializations should be performed. */
673 mem_inits = sort_mem_initializers (current_class_type, mem_inits);
674
675 in_base_initializer = 1;
676
677 /* Initialize base classes. */
678 while (mem_inits
679 && TREE_CODE (TREE_PURPOSE (mem_inits)) != FIELD_DECL)
680 {
681 tree subobject = TREE_PURPOSE (mem_inits);
682 tree arguments = TREE_VALUE (mem_inits);
683
684 /* If these initializations are taking place in a copy
685 constructor, the base class should probably be explicitly
686 initialized. */
687 if (extra_warnings && !arguments
688 && DECL_COPY_CONSTRUCTOR_P (current_function_decl)
689 && TYPE_NEEDS_CONSTRUCTING (BINFO_TYPE (subobject)))
690 warning (OPT_Wextra, "%Jbase class %q#T should be explicitly initialized in the "
691 "copy constructor",
692 current_function_decl, BINFO_TYPE (subobject));
693
694 /* If an explicit -- but empty -- initializer list was present,
695 treat it just like default initialization at this point. */
696 if (arguments == void_type_node)
697 arguments = NULL_TREE;
698
699 /* Initialize the base. */
700 if (BINFO_VIRTUAL_P (subobject))
701 construct_virtual_base (subobject, arguments);
702 else
703 {
704 tree base_addr;
705
706 base_addr = build_base_path (PLUS_EXPR, current_class_ptr,
707 subobject, 1);
708 expand_aggr_init_1 (subobject, NULL_TREE,
709 build_indirect_ref (base_addr, NULL),
710 arguments,
711 LOOKUP_NORMAL);
712 expand_cleanup_for_base (subobject, NULL_TREE);
713 }
714
715 mem_inits = TREE_CHAIN (mem_inits);
716 }
717 in_base_initializer = 0;
718
719 /* Initialize the vptrs. */
720 initialize_vtbl_ptrs (current_class_ptr);
721
722 /* Initialize the data members. */
723 while (mem_inits)
724 {
725 perform_member_init (TREE_PURPOSE (mem_inits),
726 TREE_VALUE (mem_inits));
727 mem_inits = TREE_CHAIN (mem_inits);
728 }
729 }
730
731 /* Returns the address of the vtable (i.e., the value that should be
732 assigned to the vptr) for BINFO. */
733
734 static tree
build_vtbl_address(tree binfo)735 build_vtbl_address (tree binfo)
736 {
737 tree binfo_for = binfo;
738 tree vtbl;
739
740 if (BINFO_VPTR_INDEX (binfo) && BINFO_VIRTUAL_P (binfo))
741 /* If this is a virtual primary base, then the vtable we want to store
742 is that for the base this is being used as the primary base of. We
743 can't simply skip the initialization, because we may be expanding the
744 inits of a subobject constructor where the virtual base layout
745 can be different. */
746 while (BINFO_PRIMARY_P (binfo_for))
747 binfo_for = BINFO_INHERITANCE_CHAIN (binfo_for);
748
749 /* Figure out what vtable BINFO's vtable is based on, and mark it as
750 used. */
751 vtbl = get_vtbl_decl_for_binfo (binfo_for);
752 assemble_external (vtbl);
753 TREE_USED (vtbl) = 1;
754
755 /* Now compute the address to use when initializing the vptr. */
756 vtbl = unshare_expr (BINFO_VTABLE (binfo_for));
757 if (TREE_CODE (vtbl) == VAR_DECL)
758 vtbl = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (vtbl)), vtbl);
759
760 return vtbl;
761 }
762
763 /* This code sets up the virtual function tables appropriate for
764 the pointer DECL. It is a one-ply initialization.
765
766 BINFO is the exact type that DECL is supposed to be. In
767 multiple inheritance, this might mean "C's A" if C : A, B. */
768
769 static void
expand_virtual_init(tree binfo,tree decl)770 expand_virtual_init (tree binfo, tree decl)
771 {
772 tree vtbl, vtbl_ptr;
773 tree vtt_index;
774
775 /* Compute the initializer for vptr. */
776 vtbl = build_vtbl_address (binfo);
777
778 /* We may get this vptr from a VTT, if this is a subobject
779 constructor or subobject destructor. */
780 vtt_index = BINFO_VPTR_INDEX (binfo);
781 if (vtt_index)
782 {
783 tree vtbl2;
784 tree vtt_parm;
785
786 /* Compute the value to use, when there's a VTT. */
787 vtt_parm = current_vtt_parm;
788 vtbl2 = build2 (PLUS_EXPR,
789 TREE_TYPE (vtt_parm),
790 vtt_parm,
791 vtt_index);
792 vtbl2 = build_indirect_ref (vtbl2, NULL);
793 vtbl2 = convert (TREE_TYPE (vtbl), vtbl2);
794
795 /* The actual initializer is the VTT value only in the subobject
796 constructor. In maybe_clone_body we'll substitute NULL for
797 the vtt_parm in the case of the non-subobject constructor. */
798 vtbl = build3 (COND_EXPR,
799 TREE_TYPE (vtbl),
800 build2 (EQ_EXPR, boolean_type_node,
801 current_in_charge_parm, integer_zero_node),
802 vtbl2,
803 vtbl);
804 }
805
806 /* Compute the location of the vtpr. */
807 vtbl_ptr = build_vfield_ref (build_indirect_ref (decl, NULL),
808 TREE_TYPE (binfo));
809 gcc_assert (vtbl_ptr != error_mark_node);
810
811 /* Assign the vtable to the vptr. */
812 vtbl = convert_force (TREE_TYPE (vtbl_ptr), vtbl, 0);
813 finish_expr_stmt (build_modify_expr (vtbl_ptr, NOP_EXPR, vtbl));
814 }
815
816 /* If an exception is thrown in a constructor, those base classes already
817 constructed must be destroyed. This function creates the cleanup
818 for BINFO, which has just been constructed. If FLAG is non-NULL,
819 it is a DECL which is nonzero when this base needs to be
820 destroyed. */
821
822 static void
expand_cleanup_for_base(tree binfo,tree flag)823 expand_cleanup_for_base (tree binfo, tree flag)
824 {
825 tree expr;
826
827 if (TYPE_HAS_TRIVIAL_DESTRUCTOR (BINFO_TYPE (binfo)))
828 return;
829
830 /* Call the destructor. */
831 expr = build_special_member_call (current_class_ref,
832 base_dtor_identifier,
833 NULL_TREE,
834 binfo,
835 LOOKUP_NORMAL | LOOKUP_NONVIRTUAL);
836 if (flag)
837 expr = fold_build3 (COND_EXPR, void_type_node,
838 c_common_truthvalue_conversion (flag),
839 expr, integer_zero_node);
840
841 finish_eh_cleanup (expr);
842 }
843
844 /* Construct the virtual base-class VBASE passing the ARGUMENTS to its
845 constructor. */
846
847 static void
construct_virtual_base(tree vbase,tree arguments)848 construct_virtual_base (tree vbase, tree arguments)
849 {
850 tree inner_if_stmt;
851 tree exp;
852 tree flag;
853
854 /* If there are virtual base classes with destructors, we need to
855 emit cleanups to destroy them if an exception is thrown during
856 the construction process. These exception regions (i.e., the
857 period during which the cleanups must occur) begin from the time
858 the construction is complete to the end of the function. If we
859 create a conditional block in which to initialize the
860 base-classes, then the cleanup region for the virtual base begins
861 inside a block, and ends outside of that block. This situation
862 confuses the sjlj exception-handling code. Therefore, we do not
863 create a single conditional block, but one for each
864 initialization. (That way the cleanup regions always begin
865 in the outer block.) We trust the back-end to figure out
866 that the FLAG will not change across initializations, and
867 avoid doing multiple tests. */
868 flag = TREE_CHAIN (DECL_ARGUMENTS (current_function_decl));
869 inner_if_stmt = begin_if_stmt ();
870 finish_if_stmt_cond (flag, inner_if_stmt);
871
872 /* Compute the location of the virtual base. If we're
873 constructing virtual bases, then we must be the most derived
874 class. Therefore, we don't have to look up the virtual base;
875 we already know where it is. */
876 exp = convert_to_base_statically (current_class_ref, vbase);
877
878 expand_aggr_init_1 (vbase, current_class_ref, exp, arguments,
879 LOOKUP_COMPLAIN);
880 finish_then_clause (inner_if_stmt);
881 finish_if_stmt (inner_if_stmt);
882
883 expand_cleanup_for_base (vbase, flag);
884 }
885
886 /* Find the context in which this FIELD can be initialized. */
887
888 static tree
initializing_context(tree field)889 initializing_context (tree field)
890 {
891 tree t = DECL_CONTEXT (field);
892
893 /* Anonymous union members can be initialized in the first enclosing
894 non-anonymous union context. */
895 while (t && ANON_AGGR_TYPE_P (t))
896 t = TYPE_CONTEXT (t);
897 return t;
898 }
899
900 /* Function to give error message if member initialization specification
901 is erroneous. FIELD is the member we decided to initialize.
902 TYPE is the type for which the initialization is being performed.
903 FIELD must be a member of TYPE.
904
905 MEMBER_NAME is the name of the member. */
906
907 static int
member_init_ok_or_else(tree field,tree type,tree member_name)908 member_init_ok_or_else (tree field, tree type, tree member_name)
909 {
910 if (field == error_mark_node)
911 return 0;
912 if (!field)
913 {
914 error ("class %qT does not have any field named %qD", type,
915 member_name);
916 return 0;
917 }
918 if (TREE_CODE (field) == VAR_DECL)
919 {
920 error ("%q#D is a static data member; it can only be "
921 "initialized at its definition",
922 field);
923 return 0;
924 }
925 if (TREE_CODE (field) != FIELD_DECL)
926 {
927 error ("%q#D is not a non-static data member of %qT",
928 field, type);
929 return 0;
930 }
931 if (initializing_context (field) != type)
932 {
933 error ("class %qT does not have any field named %qD", type,
934 member_name);
935 return 0;
936 }
937
938 return 1;
939 }
940
941 /* NAME is a FIELD_DECL, an IDENTIFIER_NODE which names a field, or it
942 is a _TYPE node or TYPE_DECL which names a base for that type.
943 Check the validity of NAME, and return either the base _TYPE, base
944 binfo, or the FIELD_DECL of the member. If NAME is invalid, return
945 NULL_TREE and issue a diagnostic.
946
947 An old style unnamed direct single base construction is permitted,
948 where NAME is NULL. */
949
950 tree
expand_member_init(tree name)951 expand_member_init (tree name)
952 {
953 tree basetype;
954 tree field;
955
956 if (!current_class_ref)
957 return NULL_TREE;
958
959 if (!name)
960 {
961 /* This is an obsolete unnamed base class initializer. The
962 parser will already have warned about its use. */
963 switch (BINFO_N_BASE_BINFOS (TYPE_BINFO (current_class_type)))
964 {
965 case 0:
966 error ("unnamed initializer for %qT, which has no base classes",
967 current_class_type);
968 return NULL_TREE;
969 case 1:
970 basetype = BINFO_TYPE
971 (BINFO_BASE_BINFO (TYPE_BINFO (current_class_type), 0));
972 break;
973 default:
974 error ("unnamed initializer for %qT, which uses multiple inheritance",
975 current_class_type);
976 return NULL_TREE;
977 }
978 }
979 else if (TYPE_P (name))
980 {
981 basetype = TYPE_MAIN_VARIANT (name);
982 name = TYPE_NAME (name);
983 }
984 else if (TREE_CODE (name) == TYPE_DECL)
985 basetype = TYPE_MAIN_VARIANT (TREE_TYPE (name));
986 else
987 basetype = NULL_TREE;
988
989 if (basetype)
990 {
991 tree class_binfo;
992 tree direct_binfo;
993 tree virtual_binfo;
994 int i;
995
996 if (current_template_parms)
997 return basetype;
998
999 class_binfo = TYPE_BINFO (current_class_type);
1000 direct_binfo = NULL_TREE;
1001 virtual_binfo = NULL_TREE;
1002
1003 /* Look for a direct base. */
1004 for (i = 0; BINFO_BASE_ITERATE (class_binfo, i, direct_binfo); ++i)
1005 if (SAME_BINFO_TYPE_P (BINFO_TYPE (direct_binfo), basetype))
1006 break;
1007
1008 /* Look for a virtual base -- unless the direct base is itself
1009 virtual. */
1010 if (!direct_binfo || !BINFO_VIRTUAL_P (direct_binfo))
1011 virtual_binfo = binfo_for_vbase (basetype, current_class_type);
1012
1013 /* [class.base.init]
1014
1015 If a mem-initializer-id is ambiguous because it designates
1016 both a direct non-virtual base class and an inherited virtual
1017 base class, the mem-initializer is ill-formed. */
1018 if (direct_binfo && virtual_binfo)
1019 {
1020 error ("%qD is both a direct base and an indirect virtual base",
1021 basetype);
1022 return NULL_TREE;
1023 }
1024
1025 if (!direct_binfo && !virtual_binfo)
1026 {
1027 if (CLASSTYPE_VBASECLASSES (current_class_type))
1028 error ("type %qT is not a direct or virtual base of %qT",
1029 basetype, current_class_type);
1030 else
1031 error ("type %qT is not a direct base of %qT",
1032 basetype, current_class_type);
1033 return NULL_TREE;
1034 }
1035
1036 return direct_binfo ? direct_binfo : virtual_binfo;
1037 }
1038 else
1039 {
1040 if (TREE_CODE (name) == IDENTIFIER_NODE)
1041 field = lookup_field (current_class_type, name, 1, false);
1042 else
1043 field = name;
1044
1045 if (member_init_ok_or_else (field, current_class_type, name))
1046 return field;
1047 }
1048
1049 return NULL_TREE;
1050 }
1051
1052 /* This is like `expand_member_init', only it stores one aggregate
1053 value into another.
1054
1055 INIT comes in two flavors: it is either a value which
1056 is to be stored in EXP, or it is a parameter list
1057 to go to a constructor, which will operate on EXP.
1058 If INIT is not a parameter list for a constructor, then set
1059 LOOKUP_ONLYCONVERTING.
1060 If FLAGS is LOOKUP_ONLYCONVERTING then it is the = init form of
1061 the initializer, if FLAGS is 0, then it is the (init) form.
1062 If `init' is a CONSTRUCTOR, then we emit a warning message,
1063 explaining that such initializations are invalid.
1064
1065 If INIT resolves to a CALL_EXPR which happens to return
1066 something of the type we are looking for, then we know
1067 that we can safely use that call to perform the
1068 initialization.
1069
1070 The virtual function table pointer cannot be set up here, because
1071 we do not really know its type.
1072
1073 This never calls operator=().
1074
1075 When initializing, nothing is CONST.
1076
1077 A default copy constructor may have to be used to perform the
1078 initialization.
1079
1080 A constructor or a conversion operator may have to be used to
1081 perform the initialization, but not both, as it would be ambiguous. */
1082
1083 tree
build_aggr_init(tree exp,tree init,int flags)1084 build_aggr_init (tree exp, tree init, int flags)
1085 {
1086 tree stmt_expr;
1087 tree compound_stmt;
1088 int destroy_temps;
1089 tree type = TREE_TYPE (exp);
1090 int was_const = TREE_READONLY (exp);
1091 int was_volatile = TREE_THIS_VOLATILE (exp);
1092 int is_global;
1093
1094 if (init == error_mark_node)
1095 return error_mark_node;
1096
1097 TREE_READONLY (exp) = 0;
1098 TREE_THIS_VOLATILE (exp) = 0;
1099
1100 if (init && TREE_CODE (init) != TREE_LIST)
1101 flags |= LOOKUP_ONLYCONVERTING;
1102
1103 if (TREE_CODE (type) == ARRAY_TYPE)
1104 {
1105 tree itype;
1106
1107 /* An array may not be initialized use the parenthesized
1108 initialization form -- unless the initializer is "()". */
1109 if (init && TREE_CODE (init) == TREE_LIST)
1110 {
1111 error ("bad array initializer");
1112 return error_mark_node;
1113 }
1114 /* Must arrange to initialize each element of EXP
1115 from elements of INIT. */
1116 itype = init ? TREE_TYPE (init) : NULL_TREE;
1117 if (cp_type_quals (type) != TYPE_UNQUALIFIED)
1118 TREE_TYPE (exp) = TYPE_MAIN_VARIANT (type);
1119 if (itype && cp_type_quals (itype) != TYPE_UNQUALIFIED)
1120 itype = TREE_TYPE (init) = TYPE_MAIN_VARIANT (itype);
1121 stmt_expr = build_vec_init (exp, NULL_TREE, init,
1122 /*explicit_default_init_p=*/false,
1123 itype && same_type_p (itype,
1124 TREE_TYPE (exp)));
1125 TREE_READONLY (exp) = was_const;
1126 TREE_THIS_VOLATILE (exp) = was_volatile;
1127 TREE_TYPE (exp) = type;
1128 if (init)
1129 TREE_TYPE (init) = itype;
1130 return stmt_expr;
1131 }
1132
1133 if (TREE_CODE (exp) == VAR_DECL || TREE_CODE (exp) == PARM_DECL)
1134 /* Just know that we've seen something for this node. */
1135 TREE_USED (exp) = 1;
1136
1137 TREE_TYPE (exp) = TYPE_MAIN_VARIANT (type);
1138 is_global = begin_init_stmts (&stmt_expr, &compound_stmt);
1139 destroy_temps = stmts_are_full_exprs_p ();
1140 current_stmt_tree ()->stmts_are_full_exprs_p = 0;
1141 expand_aggr_init_1 (TYPE_BINFO (type), exp, exp,
1142 init, LOOKUP_NORMAL|flags);
1143 stmt_expr = finish_init_stmts (is_global, stmt_expr, compound_stmt);
1144 current_stmt_tree ()->stmts_are_full_exprs_p = destroy_temps;
1145 TREE_TYPE (exp) = type;
1146 TREE_READONLY (exp) = was_const;
1147 TREE_THIS_VOLATILE (exp) = was_volatile;
1148
1149 return stmt_expr;
1150 }
1151
1152 static void
expand_default_init(tree binfo,tree true_exp,tree exp,tree init,int flags)1153 expand_default_init (tree binfo, tree true_exp, tree exp, tree init, int flags)
1154 {
1155 tree type = TREE_TYPE (exp);
1156 tree ctor_name;
1157
1158 /* It fails because there may not be a constructor which takes
1159 its own type as the first (or only parameter), but which does
1160 take other types via a conversion. So, if the thing initializing
1161 the expression is a unit element of type X, first try X(X&),
1162 followed by initialization by X. If neither of these work
1163 out, then look hard. */
1164 tree rval;
1165 tree parms;
1166
1167 if (init && TREE_CODE (init) != TREE_LIST
1168 && (flags & LOOKUP_ONLYCONVERTING))
1169 {
1170 /* Base subobjects should only get direct-initialization. */
1171 gcc_assert (true_exp == exp);
1172
1173 if (flags & DIRECT_BIND)
1174 /* Do nothing. We hit this in two cases: Reference initialization,
1175 where we aren't initializing a real variable, so we don't want
1176 to run a new constructor; and catching an exception, where we
1177 have already built up the constructor call so we could wrap it
1178 in an exception region. */;
1179 else if (BRACE_ENCLOSED_INITIALIZER_P (init))
1180 {
1181 /* A brace-enclosed initializer for an aggregate. */
1182 gcc_assert (CP_AGGREGATE_TYPE_P (type));
1183 init = digest_init (type, init);
1184 }
1185 else
1186 init = ocp_convert (type, init, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
1187
1188 if (TREE_CODE (init) == MUST_NOT_THROW_EXPR)
1189 /* We need to protect the initialization of a catch parm with a
1190 call to terminate(), which shows up as a MUST_NOT_THROW_EXPR
1191 around the TARGET_EXPR for the copy constructor. See
1192 initialize_handler_parm. */
1193 {
1194 TREE_OPERAND (init, 0) = build2 (INIT_EXPR, TREE_TYPE (exp), exp,
1195 TREE_OPERAND (init, 0));
1196 TREE_TYPE (init) = void_type_node;
1197 }
1198 else
1199 init = build2 (INIT_EXPR, TREE_TYPE (exp), exp, init);
1200 TREE_SIDE_EFFECTS (init) = 1;
1201 finish_expr_stmt (init);
1202 return;
1203 }
1204
1205 if (init == NULL_TREE
1206 || (TREE_CODE (init) == TREE_LIST && ! TREE_TYPE (init)))
1207 {
1208 parms = init;
1209 if (parms)
1210 init = TREE_VALUE (parms);
1211 }
1212 else
1213 parms = build_tree_list (NULL_TREE, init);
1214
1215 if (true_exp == exp)
1216 ctor_name = complete_ctor_identifier;
1217 else
1218 ctor_name = base_ctor_identifier;
1219
1220 rval = build_special_member_call (exp, ctor_name, parms, binfo, flags);
1221 if (TREE_SIDE_EFFECTS (rval))
1222 finish_expr_stmt (convert_to_void (rval, NULL));
1223 }
1224
1225 /* This function is responsible for initializing EXP with INIT
1226 (if any).
1227
1228 BINFO is the binfo of the type for who we are performing the
1229 initialization. For example, if W is a virtual base class of A and B,
1230 and C : A, B.
1231 If we are initializing B, then W must contain B's W vtable, whereas
1232 were we initializing C, W must contain C's W vtable.
1233
1234 TRUE_EXP is nonzero if it is the true expression being initialized.
1235 In this case, it may be EXP, or may just contain EXP. The reason we
1236 need this is because if EXP is a base element of TRUE_EXP, we
1237 don't necessarily know by looking at EXP where its virtual
1238 baseclass fields should really be pointing. But we do know
1239 from TRUE_EXP. In constructors, we don't know anything about
1240 the value being initialized.
1241
1242 FLAGS is just passed to `build_new_method_call'. See that function
1243 for its description. */
1244
1245 static void
expand_aggr_init_1(tree binfo,tree true_exp,tree exp,tree init,int flags)1246 expand_aggr_init_1 (tree binfo, tree true_exp, tree exp, tree init, int flags)
1247 {
1248 tree type = TREE_TYPE (exp);
1249
1250 gcc_assert (init != error_mark_node && type != error_mark_node);
1251 gcc_assert (building_stmt_tree ());
1252
1253 /* Use a function returning the desired type to initialize EXP for us.
1254 If the function is a constructor, and its first argument is
1255 NULL_TREE, know that it was meant for us--just slide exp on
1256 in and expand the constructor. Constructors now come
1257 as TARGET_EXPRs. */
1258
1259 if (init && TREE_CODE (exp) == VAR_DECL
1260 && COMPOUND_LITERAL_P (init))
1261 {
1262 /* If store_init_value returns NULL_TREE, the INIT has been
1263 recorded as the DECL_INITIAL for EXP. That means there's
1264 nothing more we have to do. */
1265 init = store_init_value (exp, init);
1266 if (init)
1267 finish_expr_stmt (init);
1268 return;
1269 }
1270
1271 /* We know that expand_default_init can handle everything we want
1272 at this point. */
1273 expand_default_init (binfo, true_exp, exp, init, flags);
1274 }
1275
1276 /* Report an error if TYPE is not a user-defined, aggregate type. If
1277 OR_ELSE is nonzero, give an error message. */
1278
1279 int
is_aggr_type(tree type,int or_else)1280 is_aggr_type (tree type, int or_else)
1281 {
1282 if (type == error_mark_node)
1283 return 0;
1284
1285 if (! IS_AGGR_TYPE (type)
1286 && TREE_CODE (type) != TEMPLATE_TYPE_PARM
1287 && TREE_CODE (type) != BOUND_TEMPLATE_TEMPLATE_PARM)
1288 {
1289 if (or_else)
1290 error ("%qT is not an aggregate type", type);
1291 return 0;
1292 }
1293 return 1;
1294 }
1295
1296 tree
get_type_value(tree name)1297 get_type_value (tree name)
1298 {
1299 if (name == error_mark_node)
1300 return NULL_TREE;
1301
1302 if (IDENTIFIER_HAS_TYPE_VALUE (name))
1303 return IDENTIFIER_TYPE_VALUE (name);
1304 else
1305 return NULL_TREE;
1306 }
1307
1308 /* Build a reference to a member of an aggregate. This is not a C++
1309 `&', but really something which can have its address taken, and
1310 then act as a pointer to member, for example TYPE :: FIELD can have
1311 its address taken by saying & TYPE :: FIELD. ADDRESS_P is true if
1312 this expression is the operand of "&".
1313
1314 @@ Prints out lousy diagnostics for operator <typename>
1315 @@ fields.
1316
1317 @@ This function should be rewritten and placed in search.c. */
1318
1319 tree
build_offset_ref(tree type,tree member,bool address_p)1320 build_offset_ref (tree type, tree member, bool address_p)
1321 {
1322 tree decl;
1323 tree basebinfo = NULL_TREE;
1324
1325 /* class templates can come in as TEMPLATE_DECLs here. */
1326 if (TREE_CODE (member) == TEMPLATE_DECL)
1327 return member;
1328
1329 if (dependent_type_p (type) || type_dependent_expression_p (member))
1330 return build_qualified_name (NULL_TREE, type, member,
1331 /*template_p=*/false);
1332
1333 gcc_assert (TYPE_P (type));
1334 if (! is_aggr_type (type, 1))
1335 return error_mark_node;
1336
1337 gcc_assert (DECL_P (member) || BASELINK_P (member));
1338 /* Callers should call mark_used before this point. */
1339 gcc_assert (!DECL_P (member) || TREE_USED (member));
1340
1341 if (!COMPLETE_TYPE_P (complete_type (type))
1342 && !TYPE_BEING_DEFINED (type))
1343 {
1344 error ("incomplete type %qT does not have member %qD", type, member);
1345 return error_mark_node;
1346 }
1347
1348 /* Entities other than non-static members need no further
1349 processing. */
1350 if (TREE_CODE (member) == TYPE_DECL)
1351 return member;
1352 if (TREE_CODE (member) == VAR_DECL || TREE_CODE (member) == CONST_DECL)
1353 return convert_from_reference (member);
1354
1355 if (TREE_CODE (member) == FIELD_DECL && DECL_C_BIT_FIELD (member))
1356 {
1357 error ("invalid pointer to bit-field %qD", member);
1358 return error_mark_node;
1359 }
1360
1361 /* Set up BASEBINFO for member lookup. */
1362 decl = maybe_dummy_object (type, &basebinfo);
1363
1364 /* A lot of this logic is now handled in lookup_member. */
1365 if (BASELINK_P (member))
1366 {
1367 /* Go from the TREE_BASELINK to the member function info. */
1368 tree t = BASELINK_FUNCTIONS (member);
1369
1370 if (TREE_CODE (t) != TEMPLATE_ID_EXPR && !really_overloaded_fn (t))
1371 {
1372 /* Get rid of a potential OVERLOAD around it. */
1373 t = OVL_CURRENT (t);
1374
1375 /* Unique functions are handled easily. */
1376
1377 /* For non-static member of base class, we need a special rule
1378 for access checking [class.protected]:
1379
1380 If the access is to form a pointer to member, the
1381 nested-name-specifier shall name the derived class
1382 (or any class derived from that class). */
1383 if (address_p && DECL_P (t)
1384 && DECL_NONSTATIC_MEMBER_P (t))
1385 perform_or_defer_access_check (TYPE_BINFO (type), t, t);
1386 else
1387 perform_or_defer_access_check (basebinfo, t, t);
1388
1389 if (DECL_STATIC_FUNCTION_P (t))
1390 return t;
1391 member = t;
1392 }
1393 else
1394 TREE_TYPE (member) = unknown_type_node;
1395 }
1396 else if (address_p && TREE_CODE (member) == FIELD_DECL)
1397 /* We need additional test besides the one in
1398 check_accessibility_of_qualified_id in case it is
1399 a pointer to non-static member. */
1400 perform_or_defer_access_check (TYPE_BINFO (type), member, member);
1401
1402 if (!address_p)
1403 {
1404 /* If MEMBER is non-static, then the program has fallen afoul of
1405 [expr.prim]:
1406
1407 An id-expression that denotes a nonstatic data member or
1408 nonstatic member function of a class can only be used:
1409
1410 -- as part of a class member access (_expr.ref_) in which the
1411 object-expression refers to the member's class or a class
1412 derived from that class, or
1413
1414 -- to form a pointer to member (_expr.unary.op_), or
1415
1416 -- in the body of a nonstatic member function of that class or
1417 of a class derived from that class (_class.mfct.nonstatic_), or
1418
1419 -- in a mem-initializer for a constructor for that class or for
1420 a class derived from that class (_class.base.init_). */
1421 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (member))
1422 {
1423 /* Build a representation of a the qualified name suitable
1424 for use as the operand to "&" -- even though the "&" is
1425 not actually present. */
1426 member = build2 (OFFSET_REF, TREE_TYPE (member), decl, member);
1427 /* In Microsoft mode, treat a non-static member function as if
1428 it were a pointer-to-member. */
1429 if (flag_ms_extensions)
1430 {
1431 PTRMEM_OK_P (member) = 1;
1432 return build_unary_op (ADDR_EXPR, member, 0);
1433 }
1434 error ("invalid use of non-static member function %qD",
1435 TREE_OPERAND (member, 1));
1436 return error_mark_node;
1437 }
1438 else if (TREE_CODE (member) == FIELD_DECL)
1439 {
1440 error ("invalid use of non-static data member %qD", member);
1441 return error_mark_node;
1442 }
1443 return member;
1444 }
1445
1446 member = build2 (OFFSET_REF, TREE_TYPE (member), decl, member);
1447 PTRMEM_OK_P (member) = 1;
1448 return member;
1449 }
1450
1451 /* If DECL is a scalar enumeration constant or variable with a
1452 constant initializer, return the initializer (or, its initializers,
1453 recursively); otherwise, return DECL. If INTEGRAL_P, the
1454 initializer is only returned if DECL is an integral
1455 constant-expression. */
1456
1457 static tree
constant_value_1(tree decl,bool integral_p)1458 constant_value_1 (tree decl, bool integral_p)
1459 {
1460 while (TREE_CODE (decl) == CONST_DECL
1461 || (integral_p
1462 ? DECL_INTEGRAL_CONSTANT_VAR_P (decl)
1463 : (TREE_CODE (decl) == VAR_DECL
1464 && CP_TYPE_CONST_NON_VOLATILE_P (TREE_TYPE (decl)))))
1465 {
1466 tree init;
1467 /* Static data members in template classes may have
1468 non-dependent initializers. References to such non-static
1469 data members are not value-dependent, so we must retrieve the
1470 initializer here. The DECL_INITIAL will have the right type,
1471 but will not have been folded because that would prevent us
1472 from performing all appropriate semantic checks at
1473 instantiation time. */
1474 if (DECL_CLASS_SCOPE_P (decl)
1475 && CLASSTYPE_TEMPLATE_INFO (DECL_CONTEXT (decl))
1476 && uses_template_parms (CLASSTYPE_TI_ARGS
1477 (DECL_CONTEXT (decl))))
1478 {
1479 ++processing_template_decl;
1480 init = fold_non_dependent_expr (DECL_INITIAL (decl));
1481 --processing_template_decl;
1482 }
1483 else
1484 {
1485 /* If DECL is a static data member in a template
1486 specialization, we must instantiate it here. The
1487 initializer for the static data member is not processed
1488 until needed; we need it now. */
1489 mark_used (decl);
1490 init = DECL_INITIAL (decl);
1491 }
1492 if (init == error_mark_node)
1493 return decl;
1494 if (!init
1495 || !TREE_TYPE (init)
1496 || (integral_p
1497 ? !INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (init))
1498 : (!TREE_CONSTANT (init)
1499 /* Do not return an aggregate constant (of which
1500 string literals are a special case), as we do not
1501 want to make inadvertent copies of such entities,
1502 and we must be sure that their addresses are the
1503 same everywhere. */
1504 || TREE_CODE (init) == CONSTRUCTOR
1505 || TREE_CODE (init) == STRING_CST)))
1506 break;
1507 decl = unshare_expr (init);
1508 }
1509 return decl;
1510 }
1511
1512 /* If DECL is a CONST_DECL, or a constant VAR_DECL initialized by
1513 constant of integral or enumeration type, then return that value.
1514 These are those variables permitted in constant expressions by
1515 [5.19/1]. */
1516
1517 tree
integral_constant_value(tree decl)1518 integral_constant_value (tree decl)
1519 {
1520 return constant_value_1 (decl, /*integral_p=*/true);
1521 }
1522
1523 /* A more relaxed version of integral_constant_value, used by the
1524 common C/C++ code and by the C++ front-end for optimization
1525 purposes. */
1526
1527 tree
decl_constant_value(tree decl)1528 decl_constant_value (tree decl)
1529 {
1530 return constant_value_1 (decl,
1531 /*integral_p=*/processing_template_decl);
1532 }
1533
1534 /* Common subroutines of build_new and build_vec_delete. */
1535
1536 /* Call the global __builtin_delete to delete ADDR. */
1537
1538 static tree
build_builtin_delete_call(tree addr)1539 build_builtin_delete_call (tree addr)
1540 {
1541 mark_used (global_delete_fndecl);
1542 return build_call (global_delete_fndecl, build_tree_list (NULL_TREE, addr));
1543 }
1544
1545 /* Build and return a NEW_EXPR. If NELTS is non-NULL, TYPE[NELTS] is
1546 the type of the object being allocated; otherwise, it's just TYPE.
1547 INIT is the initializer, if any. USE_GLOBAL_NEW is true if the
1548 user explicitly wrote "::operator new". PLACEMENT, if non-NULL, is
1549 the TREE_LIST of arguments to be provided as arguments to a
1550 placement new operator. This routine performs no semantic checks;
1551 it just creates and returns a NEW_EXPR. */
1552
1553 static tree
build_raw_new_expr(tree placement,tree type,tree nelts,tree init,int use_global_new)1554 build_raw_new_expr (tree placement, tree type, tree nelts, tree init,
1555 int use_global_new)
1556 {
1557 tree new_expr;
1558
1559 new_expr = build4 (NEW_EXPR, build_pointer_type (type), placement, type,
1560 nelts, init);
1561 NEW_EXPR_USE_GLOBAL (new_expr) = use_global_new;
1562 TREE_SIDE_EFFECTS (new_expr) = 1;
1563
1564 return new_expr;
1565 }
1566
1567 /* Generate code for a new-expression, including calling the "operator
1568 new" function, initializing the object, and, if an exception occurs
1569 during construction, cleaning up. The arguments are as for
1570 build_raw_new_expr. */
1571
1572 static tree
build_new_1(tree placement,tree type,tree nelts,tree init,bool globally_qualified_p)1573 build_new_1 (tree placement, tree type, tree nelts, tree init,
1574 bool globally_qualified_p)
1575 {
1576 tree size, rval;
1577 /* True iff this is a call to "operator new[]" instead of just
1578 "operator new". */
1579 bool array_p = false;
1580 /* True iff ARRAY_P is true and the bound of the array type is
1581 not necessarily a compile time constant. For example, VLA_P is
1582 true for "new int[f()]". */
1583 bool vla_p = false;
1584 /* The type being allocated. If ARRAY_P is true, this will be an
1585 ARRAY_TYPE. */
1586 tree full_type;
1587 /* If ARRAY_P is true, the element type of the array. This is an
1588 never ARRAY_TYPE; for something like "new int[3][4]", the
1589 ELT_TYPE is "int". If ARRAY_P is false, this is the same type as
1590 FULL_TYPE. */
1591 tree elt_type;
1592 /* The type of the new-expression. (This type is always a pointer
1593 type.) */
1594 tree pointer_type;
1595 /* A pointer type pointing to the FULL_TYPE. */
1596 tree full_pointer_type;
1597 tree outer_nelts = NULL_TREE;
1598 tree alloc_call, alloc_expr;
1599 /* The address returned by the call to "operator new". This node is
1600 a VAR_DECL and is therefore reusable. */
1601 tree alloc_node;
1602 tree alloc_fn;
1603 tree cookie_expr, init_expr;
1604 int nothrow, check_new;
1605 int use_java_new = 0;
1606 /* If non-NULL, the number of extra bytes to allocate at the
1607 beginning of the storage allocated for an array-new expression in
1608 order to store the number of elements. */
1609 tree cookie_size = NULL_TREE;
1610 /* True if the function we are calling is a placement allocation
1611 function. */
1612 bool placement_allocation_fn_p;
1613 tree args = NULL_TREE;
1614 /* True if the storage must be initialized, either by a constructor
1615 or due to an explicit new-initializer. */
1616 bool is_initialized;
1617 /* The address of the thing allocated, not including any cookie. In
1618 particular, if an array cookie is in use, DATA_ADDR is the
1619 address of the first array element. This node is a VAR_DECL, and
1620 is therefore reusable. */
1621 tree data_addr;
1622 tree init_preeval_expr = NULL_TREE;
1623
1624 if (nelts)
1625 {
1626 tree index;
1627
1628 outer_nelts = nelts;
1629 array_p = true;
1630
1631 /* ??? The middle-end will error on us for building a VLA outside a
1632 function context. Methinks that's not it's purvey. So we'll do
1633 our own VLA layout later. */
1634 vla_p = true;
1635 index = convert (sizetype, nelts);
1636 index = size_binop (MINUS_EXPR, index, size_one_node);
1637 index = build_index_type (index);
1638 full_type = build_cplus_array_type (type, NULL_TREE);
1639 /* We need a copy of the type as build_array_type will return a shared copy
1640 of the incomplete array type. */
1641 full_type = build_distinct_type_copy (full_type);
1642 TYPE_DOMAIN (full_type) = index;
1643 }
1644 else
1645 {
1646 full_type = type;
1647 if (TREE_CODE (type) == ARRAY_TYPE)
1648 {
1649 array_p = true;
1650 nelts = array_type_nelts_top (type);
1651 outer_nelts = nelts;
1652 type = TREE_TYPE (type);
1653 }
1654 }
1655
1656 if (!complete_type_or_else (type, NULL_TREE))
1657 return error_mark_node;
1658
1659 /* If our base type is an array, then make sure we know how many elements
1660 it has. */
1661 for (elt_type = type;
1662 TREE_CODE (elt_type) == ARRAY_TYPE;
1663 elt_type = TREE_TYPE (elt_type))
1664 nelts = cp_build_binary_op (MULT_EXPR, nelts,
1665 array_type_nelts_top (elt_type));
1666
1667 if (TREE_CODE (elt_type) == VOID_TYPE)
1668 {
1669 error ("invalid type %<void%> for new");
1670 return error_mark_node;
1671 }
1672
1673 if (abstract_virtuals_error (NULL_TREE, elt_type))
1674 return error_mark_node;
1675
1676 is_initialized = (TYPE_NEEDS_CONSTRUCTING (elt_type) || init);
1677 if (CP_TYPE_CONST_P (elt_type) && !is_initialized)
1678 {
1679 error ("uninitialized const in %<new%> of %q#T", elt_type);
1680 return error_mark_node;
1681 }
1682
1683 size = size_in_bytes (elt_type);
1684 if (array_p)
1685 {
1686 size = size_binop (MULT_EXPR, size, convert (sizetype, nelts));
1687 if (vla_p)
1688 {
1689 tree n, bitsize;
1690
1691 /* Do our own VLA layout. Setting TYPE_SIZE/_UNIT is
1692 necessary in order for the <INIT_EXPR <*foo> <CONSTRUCTOR
1693 ...>> to be valid. */
1694 TYPE_SIZE_UNIT (full_type) = size;
1695 n = convert (bitsizetype, nelts);
1696 bitsize = size_binop (MULT_EXPR, TYPE_SIZE (elt_type), n);
1697 TYPE_SIZE (full_type) = bitsize;
1698 }
1699 }
1700
1701 alloc_fn = NULL_TREE;
1702
1703 /* Allocate the object. */
1704 if (! placement && TYPE_FOR_JAVA (elt_type))
1705 {
1706 tree class_addr;
1707 tree class_decl = build_java_class_ref (elt_type);
1708 static const char alloc_name[] = "_Jv_AllocObject";
1709
1710 if (class_decl == error_mark_node)
1711 return error_mark_node;
1712
1713 use_java_new = 1;
1714 if (!get_global_value_if_present (get_identifier (alloc_name),
1715 &alloc_fn))
1716 {
1717 error ("call to Java constructor with %qs undefined", alloc_name);
1718 return error_mark_node;
1719 }
1720 else if (really_overloaded_fn (alloc_fn))
1721 {
1722 error ("%qD should never be overloaded", alloc_fn);
1723 return error_mark_node;
1724 }
1725 alloc_fn = OVL_CURRENT (alloc_fn);
1726 class_addr = build1 (ADDR_EXPR, jclass_node, class_decl);
1727 alloc_call = (build_function_call
1728 (alloc_fn,
1729 build_tree_list (NULL_TREE, class_addr)));
1730 }
1731 else
1732 {
1733 tree fnname;
1734 tree fns;
1735
1736 fnname = ansi_opname (array_p ? VEC_NEW_EXPR : NEW_EXPR);
1737
1738 if (!globally_qualified_p
1739 && CLASS_TYPE_P (elt_type)
1740 && (array_p
1741 ? TYPE_HAS_ARRAY_NEW_OPERATOR (elt_type)
1742 : TYPE_HAS_NEW_OPERATOR (elt_type)))
1743 {
1744 /* Use a class-specific operator new. */
1745 /* If a cookie is required, add some extra space. */
1746 if (array_p && TYPE_VEC_NEW_USES_COOKIE (elt_type))
1747 {
1748 cookie_size = targetm.cxx.get_cookie_size (elt_type);
1749 size = size_binop (PLUS_EXPR, size, cookie_size);
1750 }
1751 /* Create the argument list. */
1752 args = tree_cons (NULL_TREE, size, placement);
1753 /* Do name-lookup to find the appropriate operator. */
1754 fns = lookup_fnfields (elt_type, fnname, /*protect=*/2);
1755 if (fns == NULL_TREE)
1756 {
1757 error ("no suitable %qD found in class %qT", fnname, elt_type);
1758 return error_mark_node;
1759 }
1760 if (TREE_CODE (fns) == TREE_LIST)
1761 {
1762 error ("request for member %qD is ambiguous", fnname);
1763 print_candidates (fns);
1764 return error_mark_node;
1765 }
1766 alloc_call = build_new_method_call (build_dummy_object (elt_type),
1767 fns, args,
1768 /*conversion_path=*/NULL_TREE,
1769 LOOKUP_NORMAL,
1770 &alloc_fn);
1771 }
1772 else
1773 {
1774 /* Use a global operator new. */
1775 /* See if a cookie might be required. */
1776 if (array_p && TYPE_VEC_NEW_USES_COOKIE (elt_type))
1777 cookie_size = targetm.cxx.get_cookie_size (elt_type);
1778 else
1779 cookie_size = NULL_TREE;
1780
1781 alloc_call = build_operator_new_call (fnname, placement,
1782 &size, &cookie_size,
1783 &alloc_fn);
1784 }
1785 }
1786
1787 if (alloc_call == error_mark_node)
1788 return error_mark_node;
1789
1790 gcc_assert (alloc_fn != NULL_TREE);
1791
1792 /* In the simple case, we can stop now. */
1793 pointer_type = build_pointer_type (type);
1794 if (!cookie_size && !is_initialized)
1795 return build_nop (pointer_type, alloc_call);
1796
1797 /* While we're working, use a pointer to the type we've actually
1798 allocated. Store the result of the call in a variable so that we
1799 can use it more than once. */
1800 full_pointer_type = build_pointer_type (full_type);
1801 alloc_expr = get_target_expr (build_nop (full_pointer_type, alloc_call));
1802 alloc_node = TARGET_EXPR_SLOT (alloc_expr);
1803
1804 /* Strip any COMPOUND_EXPRs from ALLOC_CALL. */
1805 while (TREE_CODE (alloc_call) == COMPOUND_EXPR)
1806 alloc_call = TREE_OPERAND (alloc_call, 1);
1807
1808 /* Now, check to see if this function is actually a placement
1809 allocation function. This can happen even when PLACEMENT is NULL
1810 because we might have something like:
1811
1812 struct S { void* operator new (size_t, int i = 0); };
1813
1814 A call to `new S' will get this allocation function, even though
1815 there is no explicit placement argument. If there is more than
1816 one argument, or there are variable arguments, then this is a
1817 placement allocation function. */
1818 placement_allocation_fn_p
1819 = (type_num_arguments (TREE_TYPE (alloc_fn)) > 1
1820 || varargs_function_p (alloc_fn));
1821
1822 /* Preevaluate the placement args so that we don't reevaluate them for a
1823 placement delete. */
1824 if (placement_allocation_fn_p)
1825 {
1826 tree inits;
1827 stabilize_call (alloc_call, &inits);
1828 if (inits)
1829 alloc_expr = build2 (COMPOUND_EXPR, TREE_TYPE (alloc_expr), inits,
1830 alloc_expr);
1831 }
1832
1833 /* unless an allocation function is declared with an empty excep-
1834 tion-specification (_except.spec_), throw(), it indicates failure to
1835 allocate storage by throwing a bad_alloc exception (clause _except_,
1836 _lib.bad.alloc_); it returns a non-null pointer otherwise If the allo-
1837 cation function is declared with an empty exception-specification,
1838 throw(), it returns null to indicate failure to allocate storage and a
1839 non-null pointer otherwise.
1840
1841 So check for a null exception spec on the op new we just called. */
1842
1843 nothrow = TYPE_NOTHROW_P (TREE_TYPE (alloc_fn));
1844 check_new = (flag_check_new || nothrow) && ! use_java_new;
1845
1846 if (cookie_size)
1847 {
1848 tree cookie;
1849 tree cookie_ptr;
1850
1851 /* Adjust so we're pointing to the start of the object. */
1852 data_addr = get_target_expr (build2 (PLUS_EXPR, full_pointer_type,
1853 alloc_node, cookie_size));
1854
1855 /* Store the number of bytes allocated so that we can know how
1856 many elements to destroy later. We use the last sizeof
1857 (size_t) bytes to store the number of elements. */
1858 cookie_ptr = build2 (MINUS_EXPR, build_pointer_type (sizetype),
1859 data_addr, size_in_bytes (sizetype));
1860 cookie = build_indirect_ref (cookie_ptr, NULL);
1861
1862 cookie_expr = build2 (MODIFY_EXPR, sizetype, cookie, nelts);
1863
1864 if (targetm.cxx.cookie_has_size ())
1865 {
1866 /* Also store the element size. */
1867 cookie_ptr = build2 (MINUS_EXPR, build_pointer_type (sizetype),
1868 cookie_ptr, size_in_bytes (sizetype));
1869 cookie = build_indirect_ref (cookie_ptr, NULL);
1870 cookie = build2 (MODIFY_EXPR, sizetype, cookie,
1871 size_in_bytes(elt_type));
1872 cookie_expr = build2 (COMPOUND_EXPR, TREE_TYPE (cookie_expr),
1873 cookie, cookie_expr);
1874 }
1875 data_addr = TARGET_EXPR_SLOT (data_addr);
1876 }
1877 else
1878 {
1879 cookie_expr = NULL_TREE;
1880 data_addr = alloc_node;
1881 }
1882
1883 /* Now initialize the allocated object. Note that we preevaluate the
1884 initialization expression, apart from the actual constructor call or
1885 assignment--we do this because we want to delay the allocation as long
1886 as possible in order to minimize the size of the exception region for
1887 placement delete. */
1888 if (is_initialized)
1889 {
1890 bool stable;
1891
1892 init_expr = build_indirect_ref (data_addr, NULL);
1893
1894 if (array_p)
1895 {
1896 bool explicit_default_init_p = false;
1897
1898 if (init == void_zero_node)
1899 {
1900 init = NULL_TREE;
1901 explicit_default_init_p = true;
1902 }
1903 else if (init)
1904 pedwarn ("ISO C++ forbids initialization in array new");
1905
1906 init_expr
1907 = build_vec_init (init_expr,
1908 cp_build_binary_op (MINUS_EXPR, outer_nelts,
1909 integer_one_node),
1910 init,
1911 explicit_default_init_p,
1912 /*from_array=*/0);
1913
1914 /* An array initialization is stable because the initialization
1915 of each element is a full-expression, so the temporaries don't
1916 leak out. */
1917 stable = true;
1918 }
1919 else
1920 {
1921 if (init == void_zero_node)
1922 init = build_default_init (full_type, nelts);
1923
1924 if (TYPE_NEEDS_CONSTRUCTING (type))
1925 {
1926 init_expr = build_special_member_call (init_expr,
1927 complete_ctor_identifier,
1928 init, elt_type,
1929 LOOKUP_NORMAL);
1930 stable = stabilize_init (init_expr, &init_preeval_expr);
1931 }
1932 else
1933 {
1934 /* We are processing something like `new int (10)', which
1935 means allocate an int, and initialize it with 10. */
1936
1937 if (TREE_CODE (init) == TREE_LIST)
1938 init = build_x_compound_expr_from_list (init,
1939 "new initializer");
1940 else
1941 gcc_assert (TREE_CODE (init) != CONSTRUCTOR
1942 || TREE_TYPE (init) != NULL_TREE);
1943
1944 init_expr = build_modify_expr (init_expr, INIT_EXPR, init);
1945 stable = stabilize_init (init_expr, &init_preeval_expr);
1946 }
1947 }
1948
1949 if (init_expr == error_mark_node)
1950 return error_mark_node;
1951
1952 /* If any part of the object initialization terminates by throwing an
1953 exception and a suitable deallocation function can be found, the
1954 deallocation function is called to free the memory in which the
1955 object was being constructed, after which the exception continues
1956 to propagate in the context of the new-expression. If no
1957 unambiguous matching deallocation function can be found,
1958 propagating the exception does not cause the object's memory to be
1959 freed. */
1960 if (flag_exceptions && ! use_java_new)
1961 {
1962 enum tree_code dcode = array_p ? VEC_DELETE_EXPR : DELETE_EXPR;
1963 tree cleanup;
1964
1965 /* The Standard is unclear here, but the right thing to do
1966 is to use the same method for finding deallocation
1967 functions that we use for finding allocation functions. */
1968 cleanup = build_op_delete_call (dcode, alloc_node, size,
1969 globally_qualified_p,
1970 (placement_allocation_fn_p
1971 ? alloc_call : NULL_TREE),
1972 alloc_fn);
1973
1974 if (!cleanup)
1975 /* We're done. */;
1976 else if (stable)
1977 /* This is much simpler if we were able to preevaluate all of
1978 the arguments to the constructor call. */
1979 init_expr = build2 (TRY_CATCH_EXPR, void_type_node,
1980 init_expr, cleanup);
1981 else
1982 /* Ack! First we allocate the memory. Then we set our sentry
1983 variable to true, and expand a cleanup that deletes the
1984 memory if sentry is true. Then we run the constructor, and
1985 finally clear the sentry.
1986
1987 We need to do this because we allocate the space first, so
1988 if there are any temporaries with cleanups in the
1989 constructor args and we weren't able to preevaluate them, we
1990 need this EH region to extend until end of full-expression
1991 to preserve nesting. */
1992 {
1993 tree end, sentry, begin;
1994
1995 begin = get_target_expr (boolean_true_node);
1996 CLEANUP_EH_ONLY (begin) = 1;
1997
1998 sentry = TARGET_EXPR_SLOT (begin);
1999
2000 TARGET_EXPR_CLEANUP (begin)
2001 = build3 (COND_EXPR, void_type_node, sentry,
2002 cleanup, void_zero_node);
2003
2004 end = build2 (MODIFY_EXPR, TREE_TYPE (sentry),
2005 sentry, boolean_false_node);
2006
2007 init_expr
2008 = build2 (COMPOUND_EXPR, void_type_node, begin,
2009 build2 (COMPOUND_EXPR, void_type_node, init_expr,
2010 end));
2011 }
2012
2013 }
2014 }
2015 else
2016 init_expr = NULL_TREE;
2017
2018 /* Now build up the return value in reverse order. */
2019
2020 rval = data_addr;
2021
2022 if (init_expr)
2023 rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), init_expr, rval);
2024 if (cookie_expr)
2025 rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), cookie_expr, rval);
2026
2027 if (rval == alloc_node)
2028 /* If we don't have an initializer or a cookie, strip the TARGET_EXPR
2029 and return the call (which doesn't need to be adjusted). */
2030 rval = TARGET_EXPR_INITIAL (alloc_expr);
2031 else
2032 {
2033 if (check_new)
2034 {
2035 tree ifexp = cp_build_binary_op (NE_EXPR, alloc_node,
2036 integer_zero_node);
2037 rval = build_conditional_expr (ifexp, rval, alloc_node);
2038 }
2039
2040 /* Perform the allocation before anything else, so that ALLOC_NODE
2041 has been initialized before we start using it. */
2042 rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), alloc_expr, rval);
2043 }
2044
2045 if (init_preeval_expr)
2046 rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), init_preeval_expr, rval);
2047
2048 /* Convert to the final type. */
2049 rval = build_nop (pointer_type, rval);
2050
2051 /* A new-expression is never an lvalue. */
2052 gcc_assert (!lvalue_p (rval));
2053
2054 return rval;
2055 }
2056
2057 /* Generate a representation for a C++ "new" expression. PLACEMENT is
2058 a TREE_LIST of placement-new arguments (or NULL_TREE if none). If
2059 NELTS is NULL, TYPE is the type of the storage to be allocated. If
2060 NELTS is not NULL, then this is an array-new allocation; TYPE is
2061 the type of the elements in the array and NELTS is the number of
2062 elements in the array. INIT, if non-NULL, is the initializer for
2063 the new object, or void_zero_node to indicate an initializer of
2064 "()". If USE_GLOBAL_NEW is true, then the user explicitly wrote
2065 "::new" rather than just "new". */
2066
2067 tree
build_new(tree placement,tree type,tree nelts,tree init,int use_global_new)2068 build_new (tree placement, tree type, tree nelts, tree init,
2069 int use_global_new)
2070 {
2071 tree rval;
2072 tree orig_placement;
2073 tree orig_nelts;
2074 tree orig_init;
2075
2076 if (placement == error_mark_node || type == error_mark_node
2077 || init == error_mark_node)
2078 return error_mark_node;
2079
2080 orig_placement = placement;
2081 orig_nelts = nelts;
2082 orig_init = init;
2083
2084 if (processing_template_decl)
2085 {
2086 if (dependent_type_p (type)
2087 || any_type_dependent_arguments_p (placement)
2088 || (nelts && type_dependent_expression_p (nelts))
2089 || (init != void_zero_node
2090 && any_type_dependent_arguments_p (init)))
2091 return build_raw_new_expr (placement, type, nelts, init,
2092 use_global_new);
2093 placement = build_non_dependent_args (placement);
2094 if (nelts)
2095 nelts = build_non_dependent_expr (nelts);
2096 if (init != void_zero_node)
2097 init = build_non_dependent_args (init);
2098 }
2099
2100 if (nelts)
2101 {
2102 if (!build_expr_type_conversion (WANT_INT | WANT_ENUM, nelts, false))
2103 pedwarn ("size in array new must have integral type");
2104 nelts = cp_save_expr (cp_convert (sizetype, nelts));
2105 /* It is valid to allocate a zero-element array:
2106
2107 [expr.new]
2108
2109 When the value of the expression in a direct-new-declarator
2110 is zero, the allocation function is called to allocate an
2111 array with no elements. The pointer returned by the
2112 new-expression is non-null. [Note: If the library allocation
2113 function is called, the pointer returned is distinct from the
2114 pointer to any other object.]
2115
2116 However, that is not generally useful, so we issue a
2117 warning. */
2118 if (integer_zerop (nelts))
2119 warning (0, "allocating zero-element array");
2120 }
2121
2122 /* ``A reference cannot be created by the new operator. A reference
2123 is not an object (8.2.2, 8.4.3), so a pointer to it could not be
2124 returned by new.'' ARM 5.3.3 */
2125 if (TREE_CODE (type) == REFERENCE_TYPE)
2126 {
2127 error ("new cannot be applied to a reference type");
2128 type = TREE_TYPE (type);
2129 }
2130
2131 if (TREE_CODE (type) == FUNCTION_TYPE)
2132 {
2133 error ("new cannot be applied to a function type");
2134 return error_mark_node;
2135 }
2136
2137 rval = build_new_1 (placement, type, nelts, init, use_global_new);
2138 if (rval == error_mark_node)
2139 return error_mark_node;
2140
2141 if (processing_template_decl)
2142 return build_raw_new_expr (orig_placement, type, orig_nelts, orig_init,
2143 use_global_new);
2144
2145 /* Wrap it in a NOP_EXPR so warn_if_unused_value doesn't complain. */
2146 rval = build1 (NOP_EXPR, TREE_TYPE (rval), rval);
2147 TREE_NO_WARNING (rval) = 1;
2148
2149 return rval;
2150 }
2151
2152 /* Given a Java class, return a decl for the corresponding java.lang.Class. */
2153
2154 tree
build_java_class_ref(tree type)2155 build_java_class_ref (tree type)
2156 {
2157 tree name = NULL_TREE, class_decl;
2158 static tree CL_suffix = NULL_TREE;
2159 if (CL_suffix == NULL_TREE)
2160 CL_suffix = get_identifier("class$");
2161 if (jclass_node == NULL_TREE)
2162 {
2163 jclass_node = IDENTIFIER_GLOBAL_VALUE (get_identifier ("jclass"));
2164 if (jclass_node == NULL_TREE)
2165 {
2166 error ("call to Java constructor, while %<jclass%> undefined");
2167 return error_mark_node;
2168 }
2169 jclass_node = TREE_TYPE (jclass_node);
2170 }
2171
2172 /* Mangle the class$ field. */
2173 {
2174 tree field;
2175 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
2176 if (DECL_NAME (field) == CL_suffix)
2177 {
2178 mangle_decl (field);
2179 name = DECL_ASSEMBLER_NAME (field);
2180 break;
2181 }
2182 if (!field)
2183 {
2184 error ("can't find %<class$%> in %qT", type);
2185 return error_mark_node;
2186 }
2187 }
2188
2189 class_decl = IDENTIFIER_GLOBAL_VALUE (name);
2190 if (class_decl == NULL_TREE)
2191 {
2192 class_decl = build_decl (VAR_DECL, name, TREE_TYPE (jclass_node));
2193 TREE_STATIC (class_decl) = 1;
2194 DECL_EXTERNAL (class_decl) = 1;
2195 TREE_PUBLIC (class_decl) = 1;
2196 DECL_ARTIFICIAL (class_decl) = 1;
2197 DECL_IGNORED_P (class_decl) = 1;
2198 pushdecl_top_level (class_decl);
2199 make_decl_rtl (class_decl);
2200 }
2201 return class_decl;
2202 }
2203
2204 static tree
build_vec_delete_1(tree base,tree maxindex,tree type,special_function_kind auto_delete_vec,int use_global_delete)2205 build_vec_delete_1 (tree base, tree maxindex, tree type,
2206 special_function_kind auto_delete_vec, int use_global_delete)
2207 {
2208 tree virtual_size;
2209 tree ptype = build_pointer_type (type = complete_type (type));
2210 tree size_exp = size_in_bytes (type);
2211
2212 /* Temporary variables used by the loop. */
2213 tree tbase, tbase_init;
2214
2215 /* This is the body of the loop that implements the deletion of a
2216 single element, and moves temp variables to next elements. */
2217 tree body;
2218
2219 /* This is the LOOP_EXPR that governs the deletion of the elements. */
2220 tree loop = 0;
2221
2222 /* This is the thing that governs what to do after the loop has run. */
2223 tree deallocate_expr = 0;
2224
2225 /* This is the BIND_EXPR which holds the outermost iterator of the
2226 loop. It is convenient to set this variable up and test it before
2227 executing any other code in the loop.
2228 This is also the containing expression returned by this function. */
2229 tree controller = NULL_TREE;
2230
2231 /* We should only have 1-D arrays here. */
2232 gcc_assert (TREE_CODE (type) != ARRAY_TYPE);
2233
2234 if (! IS_AGGR_TYPE (type) || TYPE_HAS_TRIVIAL_DESTRUCTOR (type))
2235 goto no_destructor;
2236
2237 /* The below is short by the cookie size. */
2238 virtual_size = size_binop (MULT_EXPR, size_exp,
2239 convert (sizetype, maxindex));
2240
2241 tbase = create_temporary_var (ptype);
2242 tbase_init = build_modify_expr (tbase, NOP_EXPR,
2243 fold_build2 (PLUS_EXPR, ptype,
2244 base,
2245 virtual_size));
2246 DECL_REGISTER (tbase) = 1;
2247 controller = build3 (BIND_EXPR, void_type_node, tbase,
2248 NULL_TREE, NULL_TREE);
2249 TREE_SIDE_EFFECTS (controller) = 1;
2250
2251 body = build1 (EXIT_EXPR, void_type_node,
2252 build2 (EQ_EXPR, boolean_type_node, tbase,
2253 fold_convert (ptype, base)));
2254 body = build_compound_expr
2255 (body, build_modify_expr (tbase, NOP_EXPR,
2256 build2 (MINUS_EXPR, ptype, tbase, size_exp)));
2257 body = build_compound_expr
2258 (body, build_delete (ptype, tbase, sfk_complete_destructor,
2259 LOOKUP_NORMAL|LOOKUP_DESTRUCTOR, 1));
2260
2261 loop = build1 (LOOP_EXPR, void_type_node, body);
2262 loop = build_compound_expr (tbase_init, loop);
2263
2264 no_destructor:
2265 /* If the delete flag is one, or anything else with the low bit set,
2266 delete the storage. */
2267 if (auto_delete_vec != sfk_base_destructor)
2268 {
2269 tree base_tbd;
2270
2271 /* The below is short by the cookie size. */
2272 virtual_size = size_binop (MULT_EXPR, size_exp,
2273 convert (sizetype, maxindex));
2274
2275 if (! TYPE_VEC_NEW_USES_COOKIE (type))
2276 /* no header */
2277 base_tbd = base;
2278 else
2279 {
2280 tree cookie_size;
2281
2282 cookie_size = targetm.cxx.get_cookie_size (type);
2283 base_tbd
2284 = cp_convert (ptype,
2285 cp_build_binary_op (MINUS_EXPR,
2286 cp_convert (string_type_node,
2287 base),
2288 cookie_size));
2289 /* True size with header. */
2290 virtual_size = size_binop (PLUS_EXPR, virtual_size, cookie_size);
2291 }
2292
2293 if (auto_delete_vec == sfk_deleting_destructor)
2294 deallocate_expr = build_op_delete_call (VEC_DELETE_EXPR,
2295 base_tbd, virtual_size,
2296 use_global_delete & 1,
2297 /*placement=*/NULL_TREE,
2298 /*alloc_fn=*/NULL_TREE);
2299 }
2300
2301 body = loop;
2302 if (!deallocate_expr)
2303 ;
2304 else if (!body)
2305 body = deallocate_expr;
2306 else
2307 body = build_compound_expr (body, deallocate_expr);
2308
2309 if (!body)
2310 body = integer_zero_node;
2311
2312 /* Outermost wrapper: If pointer is null, punt. */
2313 body = fold_build3 (COND_EXPR, void_type_node,
2314 fold_build2 (NE_EXPR, boolean_type_node, base,
2315 convert (TREE_TYPE (base),
2316 integer_zero_node)),
2317 body, integer_zero_node);
2318 body = build1 (NOP_EXPR, void_type_node, body);
2319
2320 if (controller)
2321 {
2322 TREE_OPERAND (controller, 1) = body;
2323 body = controller;
2324 }
2325
2326 if (TREE_CODE (base) == SAVE_EXPR)
2327 /* Pre-evaluate the SAVE_EXPR outside of the BIND_EXPR. */
2328 body = build2 (COMPOUND_EXPR, void_type_node, base, body);
2329
2330 return convert_to_void (body, /*implicit=*/NULL);
2331 }
2332
2333 /* Create an unnamed variable of the indicated TYPE. */
2334
2335 tree
create_temporary_var(tree type)2336 create_temporary_var (tree type)
2337 {
2338 tree decl;
2339
2340 decl = build_decl (VAR_DECL, NULL_TREE, type);
2341 TREE_USED (decl) = 1;
2342 DECL_ARTIFICIAL (decl) = 1;
2343 DECL_IGNORED_P (decl) = 1;
2344 DECL_SOURCE_LOCATION (decl) = input_location;
2345 DECL_CONTEXT (decl) = current_function_decl;
2346
2347 return decl;
2348 }
2349
2350 /* Create a new temporary variable of the indicated TYPE, initialized
2351 to INIT.
2352
2353 It is not entered into current_binding_level, because that breaks
2354 things when it comes time to do final cleanups (which take place
2355 "outside" the binding contour of the function). */
2356
2357 static tree
get_temp_regvar(tree type,tree init)2358 get_temp_regvar (tree type, tree init)
2359 {
2360 tree decl;
2361
2362 decl = create_temporary_var (type);
2363 add_decl_expr (decl);
2364
2365 finish_expr_stmt (build_modify_expr (decl, INIT_EXPR, init));
2366
2367 return decl;
2368 }
2369
2370 /* `build_vec_init' returns tree structure that performs
2371 initialization of a vector of aggregate types.
2372
2373 BASE is a reference to the vector, of ARRAY_TYPE.
2374 MAXINDEX is the maximum index of the array (one less than the
2375 number of elements). It is only used if
2376 TYPE_DOMAIN (TREE_TYPE (BASE)) == NULL_TREE.
2377
2378 INIT is the (possibly NULL) initializer.
2379
2380 If EXPLICIT_DEFAULT_INIT_P is true, then INIT must be NULL. All
2381 elements in the array are default-initialized.
2382
2383 FROM_ARRAY is 0 if we should init everything with INIT
2384 (i.e., every element initialized from INIT).
2385 FROM_ARRAY is 1 if we should index into INIT in parallel
2386 with initialization of DECL.
2387 FROM_ARRAY is 2 if we should index into INIT in parallel,
2388 but use assignment instead of initialization. */
2389
2390 tree
build_vec_init(tree base,tree maxindex,tree init,bool explicit_default_init_p,int from_array)2391 build_vec_init (tree base, tree maxindex, tree init,
2392 bool explicit_default_init_p,
2393 int from_array)
2394 {
2395 tree rval;
2396 tree base2 = NULL_TREE;
2397 tree size;
2398 tree itype = NULL_TREE;
2399 tree iterator;
2400 /* The type of the array. */
2401 tree atype = TREE_TYPE (base);
2402 /* The type of an element in the array. */
2403 tree type = TREE_TYPE (atype);
2404 /* The element type reached after removing all outer array
2405 types. */
2406 tree inner_elt_type;
2407 /* The type of a pointer to an element in the array. */
2408 tree ptype;
2409 tree stmt_expr;
2410 tree compound_stmt;
2411 int destroy_temps;
2412 tree try_block = NULL_TREE;
2413 int num_initialized_elts = 0;
2414 bool is_global;
2415
2416 if (TYPE_DOMAIN (atype))
2417 maxindex = array_type_nelts (atype);
2418
2419 if (maxindex == NULL_TREE || maxindex == error_mark_node)
2420 return error_mark_node;
2421
2422 if (explicit_default_init_p)
2423 gcc_assert (!init);
2424
2425 inner_elt_type = strip_array_types (atype);
2426 if (init
2427 && (from_array == 2
2428 ? (!CLASS_TYPE_P (inner_elt_type)
2429 || !TYPE_HAS_COMPLEX_ASSIGN_REF (inner_elt_type))
2430 : !TYPE_NEEDS_CONSTRUCTING (type))
2431 && ((TREE_CODE (init) == CONSTRUCTOR
2432 /* Don't do this if the CONSTRUCTOR might contain something
2433 that might throw and require us to clean up. */
2434 && (VEC_empty (constructor_elt, CONSTRUCTOR_ELTS (init))
2435 || ! TYPE_HAS_NONTRIVIAL_DESTRUCTOR (inner_elt_type)))
2436 || from_array))
2437 {
2438 /* Do non-default initialization of POD arrays resulting from
2439 brace-enclosed initializers. In this case, digest_init and
2440 store_constructor will handle the semantics for us. */
2441
2442 stmt_expr = build2 (INIT_EXPR, atype, base, init);
2443 return stmt_expr;
2444 }
2445
2446 maxindex = cp_convert (ptrdiff_type_node, maxindex);
2447 ptype = build_pointer_type (type);
2448 size = size_in_bytes (type);
2449 if (TREE_CODE (TREE_TYPE (base)) == ARRAY_TYPE)
2450 base = cp_convert (ptype, decay_conversion (base));
2451
2452 /* The code we are generating looks like:
2453 ({
2454 T* t1 = (T*) base;
2455 T* rval = t1;
2456 ptrdiff_t iterator = maxindex;
2457 try {
2458 for (; iterator != -1; --iterator) {
2459 ... initialize *t1 ...
2460 ++t1;
2461 }
2462 } catch (...) {
2463 ... destroy elements that were constructed ...
2464 }
2465 rval;
2466 })
2467
2468 We can omit the try and catch blocks if we know that the
2469 initialization will never throw an exception, or if the array
2470 elements do not have destructors. We can omit the loop completely if
2471 the elements of the array do not have constructors.
2472
2473 We actually wrap the entire body of the above in a STMT_EXPR, for
2474 tidiness.
2475
2476 When copying from array to another, when the array elements have
2477 only trivial copy constructors, we should use __builtin_memcpy
2478 rather than generating a loop. That way, we could take advantage
2479 of whatever cleverness the back-end has for dealing with copies
2480 of blocks of memory. */
2481
2482 is_global = begin_init_stmts (&stmt_expr, &compound_stmt);
2483 destroy_temps = stmts_are_full_exprs_p ();
2484 current_stmt_tree ()->stmts_are_full_exprs_p = 0;
2485 rval = get_temp_regvar (ptype, base);
2486 base = get_temp_regvar (ptype, rval);
2487 iterator = get_temp_regvar (ptrdiff_type_node, maxindex);
2488
2489 /* Protect the entire array initialization so that we can destroy
2490 the partially constructed array if an exception is thrown.
2491 But don't do this if we're assigning. */
2492 if (flag_exceptions && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
2493 && from_array != 2)
2494 {
2495 try_block = begin_try_block ();
2496 }
2497
2498 if (init != NULL_TREE && TREE_CODE (init) == CONSTRUCTOR)
2499 {
2500 /* Do non-default initialization of non-POD arrays resulting from
2501 brace-enclosed initializers. */
2502 unsigned HOST_WIDE_INT idx;
2503 tree elt;
2504 from_array = 0;
2505
2506 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (init), idx, elt)
2507 {
2508 tree baseref = build1 (INDIRECT_REF, type, base);
2509
2510 num_initialized_elts++;
2511
2512 current_stmt_tree ()->stmts_are_full_exprs_p = 1;
2513 if (IS_AGGR_TYPE (type) || TREE_CODE (type) == ARRAY_TYPE)
2514 finish_expr_stmt (build_aggr_init (baseref, elt, 0));
2515 else
2516 finish_expr_stmt (build_modify_expr (baseref, NOP_EXPR,
2517 elt));
2518 current_stmt_tree ()->stmts_are_full_exprs_p = 0;
2519
2520 finish_expr_stmt (build_unary_op (PREINCREMENT_EXPR, base, 0));
2521 finish_expr_stmt (build_unary_op (PREDECREMENT_EXPR, iterator, 0));
2522 }
2523
2524 /* Clear out INIT so that we don't get confused below. */
2525 init = NULL_TREE;
2526 }
2527 else if (from_array)
2528 {
2529 /* If initializing one array from another, initialize element by
2530 element. We rely upon the below calls the do argument
2531 checking. */
2532 if (init)
2533 {
2534 base2 = decay_conversion (init);
2535 itype = TREE_TYPE (base2);
2536 base2 = get_temp_regvar (itype, base2);
2537 itype = TREE_TYPE (itype);
2538 }
2539 else if (TYPE_LANG_SPECIFIC (type)
2540 && TYPE_NEEDS_CONSTRUCTING (type)
2541 && ! TYPE_HAS_DEFAULT_CONSTRUCTOR (type))
2542 {
2543 error ("initializer ends prematurely");
2544 return error_mark_node;
2545 }
2546 }
2547
2548 /* Now, default-initialize any remaining elements. We don't need to
2549 do that if a) the type does not need constructing, or b) we've
2550 already initialized all the elements.
2551
2552 We do need to keep going if we're copying an array. */
2553
2554 if (from_array
2555 || ((TYPE_NEEDS_CONSTRUCTING (type) || explicit_default_init_p)
2556 && ! (host_integerp (maxindex, 0)
2557 && (num_initialized_elts
2558 == tree_low_cst (maxindex, 0) + 1))))
2559 {
2560 /* If the ITERATOR is equal to -1, then we don't have to loop;
2561 we've already initialized all the elements. */
2562 tree for_stmt;
2563 tree elt_init;
2564 tree to;
2565
2566 for_stmt = begin_for_stmt ();
2567 finish_for_init_stmt (for_stmt);
2568 finish_for_cond (build2 (NE_EXPR, boolean_type_node, iterator,
2569 build_int_cst (TREE_TYPE (iterator), -1)),
2570 for_stmt);
2571 finish_for_expr (build_unary_op (PREDECREMENT_EXPR, iterator, 0),
2572 for_stmt);
2573
2574 to = build1 (INDIRECT_REF, type, base);
2575
2576 if (from_array)
2577 {
2578 tree from;
2579
2580 if (base2)
2581 from = build1 (INDIRECT_REF, itype, base2);
2582 else
2583 from = NULL_TREE;
2584
2585 if (from_array == 2)
2586 elt_init = build_modify_expr (to, NOP_EXPR, from);
2587 else if (TYPE_NEEDS_CONSTRUCTING (type))
2588 elt_init = build_aggr_init (to, from, 0);
2589 else if (from)
2590 elt_init = build_modify_expr (to, NOP_EXPR, from);
2591 else
2592 gcc_unreachable ();
2593 }
2594 else if (TREE_CODE (type) == ARRAY_TYPE)
2595 {
2596 if (init != 0)
2597 sorry
2598 ("cannot initialize multi-dimensional array with initializer");
2599 elt_init = build_vec_init (build1 (INDIRECT_REF, type, base),
2600 0, 0,
2601 /*explicit_default_init_p=*/false,
2602 0);
2603 }
2604 else if (!TYPE_NEEDS_CONSTRUCTING (type))
2605 elt_init = (build_modify_expr
2606 (to, INIT_EXPR,
2607 build_zero_init (type, size_one_node,
2608 /*static_storage_p=*/false)));
2609 else
2610 elt_init = build_aggr_init (to, init, 0);
2611
2612 current_stmt_tree ()->stmts_are_full_exprs_p = 1;
2613 finish_expr_stmt (elt_init);
2614 current_stmt_tree ()->stmts_are_full_exprs_p = 0;
2615
2616 finish_expr_stmt (build_unary_op (PREINCREMENT_EXPR, base, 0));
2617 if (base2)
2618 finish_expr_stmt (build_unary_op (PREINCREMENT_EXPR, base2, 0));
2619
2620 finish_for_stmt (for_stmt);
2621 }
2622
2623 /* Make sure to cleanup any partially constructed elements. */
2624 if (flag_exceptions && TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
2625 && from_array != 2)
2626 {
2627 tree e;
2628 tree m = cp_build_binary_op (MINUS_EXPR, maxindex, iterator);
2629
2630 /* Flatten multi-dimensional array since build_vec_delete only
2631 expects one-dimensional array. */
2632 if (TREE_CODE (type) == ARRAY_TYPE)
2633 m = cp_build_binary_op (MULT_EXPR, m,
2634 array_type_nelts_total (type));
2635
2636 finish_cleanup_try_block (try_block);
2637 e = build_vec_delete_1 (rval, m,
2638 inner_elt_type, sfk_base_destructor,
2639 /*use_global_delete=*/0);
2640 finish_cleanup (e, try_block);
2641 }
2642
2643 /* The value of the array initialization is the array itself, RVAL
2644 is a pointer to the first element. */
2645 finish_stmt_expr_expr (rval, stmt_expr);
2646
2647 stmt_expr = finish_init_stmts (is_global, stmt_expr, compound_stmt);
2648
2649 /* Now convert make the result have the correct type. */
2650 atype = build_pointer_type (atype);
2651 stmt_expr = build1 (NOP_EXPR, atype, stmt_expr);
2652 stmt_expr = build_indirect_ref (stmt_expr, NULL);
2653
2654 current_stmt_tree ()->stmts_are_full_exprs_p = destroy_temps;
2655 return stmt_expr;
2656 }
2657
2658 /* Call the DTOR_KIND destructor for EXP. FLAGS are as for
2659 build_delete. */
2660
2661 static tree
build_dtor_call(tree exp,special_function_kind dtor_kind,int flags)2662 build_dtor_call (tree exp, special_function_kind dtor_kind, int flags)
2663 {
2664 tree name;
2665 tree fn;
2666 switch (dtor_kind)
2667 {
2668 case sfk_complete_destructor:
2669 name = complete_dtor_identifier;
2670 break;
2671
2672 case sfk_base_destructor:
2673 name = base_dtor_identifier;
2674 break;
2675
2676 case sfk_deleting_destructor:
2677 name = deleting_dtor_identifier;
2678 break;
2679
2680 default:
2681 gcc_unreachable ();
2682 }
2683 fn = lookup_fnfields (TREE_TYPE (exp), name, /*protect=*/2);
2684 return build_new_method_call (exp, fn,
2685 /*args=*/NULL_TREE,
2686 /*conversion_path=*/NULL_TREE,
2687 flags,
2688 /*fn_p=*/NULL);
2689 }
2690
2691 /* Generate a call to a destructor. TYPE is the type to cast ADDR to.
2692 ADDR is an expression which yields the store to be destroyed.
2693 AUTO_DELETE is the name of the destructor to call, i.e., either
2694 sfk_complete_destructor, sfk_base_destructor, or
2695 sfk_deleting_destructor.
2696
2697 FLAGS is the logical disjunction of zero or more LOOKUP_
2698 flags. See cp-tree.h for more info. */
2699
2700 tree
build_delete(tree type,tree addr,special_function_kind auto_delete,int flags,int use_global_delete)2701 build_delete (tree type, tree addr, special_function_kind auto_delete,
2702 int flags, int use_global_delete)
2703 {
2704 tree expr;
2705
2706 if (addr == error_mark_node)
2707 return error_mark_node;
2708
2709 /* Can happen when CURRENT_EXCEPTION_OBJECT gets its type
2710 set to `error_mark_node' before it gets properly cleaned up. */
2711 if (type == error_mark_node)
2712 return error_mark_node;
2713
2714 type = TYPE_MAIN_VARIANT (type);
2715
2716 if (TREE_CODE (type) == POINTER_TYPE)
2717 {
2718 bool complete_p = true;
2719
2720 type = TYPE_MAIN_VARIANT (TREE_TYPE (type));
2721 if (TREE_CODE (type) == ARRAY_TYPE)
2722 goto handle_array;
2723
2724 /* We don't want to warn about delete of void*, only other
2725 incomplete types. Deleting other incomplete types
2726 invokes undefined behavior, but it is not ill-formed, so
2727 compile to something that would even do The Right Thing
2728 (TM) should the type have a trivial dtor and no delete
2729 operator. */
2730 if (!VOID_TYPE_P (type))
2731 {
2732 complete_type (type);
2733 if (!COMPLETE_TYPE_P (type))
2734 {
2735 warning (0, "possible problem detected in invocation of "
2736 "delete operator:");
2737 cxx_incomplete_type_diagnostic (addr, type, 1);
2738 inform ("neither the destructor nor the class-specific "
2739 "operator delete will be called, even if they are "
2740 "declared when the class is defined.");
2741 complete_p = false;
2742 }
2743 }
2744 if (VOID_TYPE_P (type) || !complete_p || !IS_AGGR_TYPE (type))
2745 /* Call the builtin operator delete. */
2746 return build_builtin_delete_call (addr);
2747 if (TREE_SIDE_EFFECTS (addr))
2748 addr = save_expr (addr);
2749
2750 /* Throw away const and volatile on target type of addr. */
2751 addr = convert_force (build_pointer_type (type), addr, 0);
2752 }
2753 else if (TREE_CODE (type) == ARRAY_TYPE)
2754 {
2755 handle_array:
2756
2757 if (TYPE_DOMAIN (type) == NULL_TREE)
2758 {
2759 error ("unknown array size in delete");
2760 return error_mark_node;
2761 }
2762 return build_vec_delete (addr, array_type_nelts (type),
2763 auto_delete, use_global_delete);
2764 }
2765 else
2766 {
2767 /* Don't check PROTECT here; leave that decision to the
2768 destructor. If the destructor is accessible, call it,
2769 else report error. */
2770 addr = build_unary_op (ADDR_EXPR, addr, 0);
2771 if (TREE_SIDE_EFFECTS (addr))
2772 addr = save_expr (addr);
2773
2774 addr = convert_force (build_pointer_type (type), addr, 0);
2775 }
2776
2777 gcc_assert (IS_AGGR_TYPE (type));
2778
2779 if (TYPE_HAS_TRIVIAL_DESTRUCTOR (type))
2780 {
2781 if (auto_delete != sfk_deleting_destructor)
2782 return void_zero_node;
2783
2784 return build_op_delete_call (DELETE_EXPR, addr,
2785 cxx_sizeof_nowarn (type),
2786 use_global_delete,
2787 /*placement=*/NULL_TREE,
2788 /*alloc_fn=*/NULL_TREE);
2789 }
2790 else
2791 {
2792 tree do_delete = NULL_TREE;
2793 tree ifexp;
2794
2795 if (CLASSTYPE_LAZY_DESTRUCTOR (type))
2796 lazily_declare_fn (sfk_destructor, type);
2797
2798 /* For `::delete x', we must not use the deleting destructor
2799 since then we would not be sure to get the global `operator
2800 delete'. */
2801 if (use_global_delete && auto_delete == sfk_deleting_destructor)
2802 {
2803 /* We will use ADDR multiple times so we must save it. */
2804 addr = save_expr (addr);
2805 /* Delete the object. */
2806 do_delete = build_builtin_delete_call (addr);
2807 /* Otherwise, treat this like a complete object destructor
2808 call. */
2809 auto_delete = sfk_complete_destructor;
2810 }
2811 /* If the destructor is non-virtual, there is no deleting
2812 variant. Instead, we must explicitly call the appropriate
2813 `operator delete' here. */
2814 else if (!DECL_VIRTUAL_P (CLASSTYPE_DESTRUCTORS (type))
2815 && auto_delete == sfk_deleting_destructor)
2816 {
2817 /* We will use ADDR multiple times so we must save it. */
2818 addr = save_expr (addr);
2819 /* Build the call. */
2820 do_delete = build_op_delete_call (DELETE_EXPR,
2821 addr,
2822 cxx_sizeof_nowarn (type),
2823 /*global_p=*/false,
2824 /*placement=*/NULL_TREE,
2825 /*alloc_fn=*/NULL_TREE);
2826 /* Call the complete object destructor. */
2827 auto_delete = sfk_complete_destructor;
2828 }
2829 else if (auto_delete == sfk_deleting_destructor
2830 && TYPE_GETS_REG_DELETE (type))
2831 {
2832 /* Make sure we have access to the member op delete, even though
2833 we'll actually be calling it from the destructor. */
2834 build_op_delete_call (DELETE_EXPR, addr, cxx_sizeof_nowarn (type),
2835 /*global_p=*/false,
2836 /*placement=*/NULL_TREE,
2837 /*alloc_fn=*/NULL_TREE);
2838 }
2839
2840 expr = build_dtor_call (build_indirect_ref (addr, NULL),
2841 auto_delete, flags);
2842 if (do_delete)
2843 expr = build2 (COMPOUND_EXPR, void_type_node, expr, do_delete);
2844
2845 if (flags & LOOKUP_DESTRUCTOR)
2846 /* Explicit destructor call; don't check for null pointer. */
2847 ifexp = integer_one_node;
2848 else
2849 /* Handle deleting a null pointer. */
2850 ifexp = fold (cp_build_binary_op (NE_EXPR, addr, integer_zero_node));
2851
2852 if (ifexp != integer_one_node)
2853 expr = build3 (COND_EXPR, void_type_node,
2854 ifexp, expr, void_zero_node);
2855
2856 return expr;
2857 }
2858 }
2859
2860 /* At the beginning of a destructor, push cleanups that will call the
2861 destructors for our base classes and members.
2862
2863 Called from begin_destructor_body. */
2864
2865 void
push_base_cleanups(void)2866 push_base_cleanups (void)
2867 {
2868 tree binfo, base_binfo;
2869 int i;
2870 tree member;
2871 tree expr;
2872 VEC(tree,gc) *vbases;
2873
2874 /* Run destructors for all virtual baseclasses. */
2875 if (CLASSTYPE_VBASECLASSES (current_class_type))
2876 {
2877 tree cond = (condition_conversion
2878 (build2 (BIT_AND_EXPR, integer_type_node,
2879 current_in_charge_parm,
2880 integer_two_node)));
2881
2882 /* The CLASSTYPE_VBASECLASSES vector is in initialization
2883 order, which is also the right order for pushing cleanups. */
2884 for (vbases = CLASSTYPE_VBASECLASSES (current_class_type), i = 0;
2885 VEC_iterate (tree, vbases, i, base_binfo); i++)
2886 {
2887 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (BINFO_TYPE (base_binfo)))
2888 {
2889 expr = build_special_member_call (current_class_ref,
2890 base_dtor_identifier,
2891 NULL_TREE,
2892 base_binfo,
2893 (LOOKUP_NORMAL
2894 | LOOKUP_NONVIRTUAL));
2895 expr = build3 (COND_EXPR, void_type_node, cond,
2896 expr, void_zero_node);
2897 finish_decl_cleanup (NULL_TREE, expr);
2898 }
2899 }
2900 }
2901
2902 /* Take care of the remaining baseclasses. */
2903 for (binfo = TYPE_BINFO (current_class_type), i = 0;
2904 BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
2905 {
2906 if (TYPE_HAS_TRIVIAL_DESTRUCTOR (BINFO_TYPE (base_binfo))
2907 || BINFO_VIRTUAL_P (base_binfo))
2908 continue;
2909
2910 expr = build_special_member_call (current_class_ref,
2911 base_dtor_identifier,
2912 NULL_TREE, base_binfo,
2913 LOOKUP_NORMAL | LOOKUP_NONVIRTUAL);
2914 finish_decl_cleanup (NULL_TREE, expr);
2915 }
2916
2917 for (member = TYPE_FIELDS (current_class_type); member;
2918 member = TREE_CHAIN (member))
2919 {
2920 if (TREE_TYPE (member) == error_mark_node
2921 || TREE_CODE (member) != FIELD_DECL
2922 || DECL_ARTIFICIAL (member))
2923 continue;
2924 if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TREE_TYPE (member)))
2925 {
2926 tree this_member = (build_class_member_access_expr
2927 (current_class_ref, member,
2928 /*access_path=*/NULL_TREE,
2929 /*preserve_reference=*/false));
2930 tree this_type = TREE_TYPE (member);
2931 expr = build_delete (this_type, this_member,
2932 sfk_complete_destructor,
2933 LOOKUP_NONVIRTUAL|LOOKUP_DESTRUCTOR|LOOKUP_NORMAL,
2934 0);
2935 finish_decl_cleanup (NULL_TREE, expr);
2936 }
2937 }
2938 }
2939
2940 /* Build a C++ vector delete expression.
2941 MAXINDEX is the number of elements to be deleted.
2942 ELT_SIZE is the nominal size of each element in the vector.
2943 BASE is the expression that should yield the store to be deleted.
2944 This function expands (or synthesizes) these calls itself.
2945 AUTO_DELETE_VEC says whether the container (vector) should be deallocated.
2946
2947 This also calls delete for virtual baseclasses of elements of the vector.
2948
2949 Update: MAXINDEX is no longer needed. The size can be extracted from the
2950 start of the vector for pointers, and from the type for arrays. We still
2951 use MAXINDEX for arrays because it happens to already have one of the
2952 values we'd have to extract. (We could use MAXINDEX with pointers to
2953 confirm the size, and trap if the numbers differ; not clear that it'd
2954 be worth bothering.) */
2955
2956 tree
build_vec_delete(tree base,tree maxindex,special_function_kind auto_delete_vec,int use_global_delete)2957 build_vec_delete (tree base, tree maxindex,
2958 special_function_kind auto_delete_vec, int use_global_delete)
2959 {
2960 tree type;
2961 tree rval;
2962 tree base_init = NULL_TREE;
2963
2964 type = TREE_TYPE (base);
2965
2966 if (TREE_CODE (type) == POINTER_TYPE)
2967 {
2968 /* Step back one from start of vector, and read dimension. */
2969 tree cookie_addr;
2970
2971 if (TREE_SIDE_EFFECTS (base))
2972 {
2973 base_init = get_target_expr (base);
2974 base = TARGET_EXPR_SLOT (base_init);
2975 }
2976 type = strip_array_types (TREE_TYPE (type));
2977 cookie_addr = build2 (MINUS_EXPR,
2978 build_pointer_type (sizetype),
2979 base,
2980 TYPE_SIZE_UNIT (sizetype));
2981 maxindex = build_indirect_ref (cookie_addr, NULL);
2982 }
2983 else if (TREE_CODE (type) == ARRAY_TYPE)
2984 {
2985 /* Get the total number of things in the array, maxindex is a
2986 bad name. */
2987 maxindex = array_type_nelts_total (type);
2988 type = strip_array_types (type);
2989 base = build_unary_op (ADDR_EXPR, base, 1);
2990 if (TREE_SIDE_EFFECTS (base))
2991 {
2992 base_init = get_target_expr (base);
2993 base = TARGET_EXPR_SLOT (base_init);
2994 }
2995 }
2996 else
2997 {
2998 if (base != error_mark_node)
2999 error ("type to vector delete is neither pointer or array type");
3000 return error_mark_node;
3001 }
3002
3003 rval = build_vec_delete_1 (base, maxindex, type, auto_delete_vec,
3004 use_global_delete);
3005 if (base_init)
3006 rval = build2 (COMPOUND_EXPR, TREE_TYPE (rval), base_init, rval);
3007
3008 return rval;
3009 }
3010