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re PR c++/43126 ("at this point in file" warnings are upside down)
[gcc.git] / gcc / c-typeck.c
1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
5
6 This file is part of GCC.
7
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
12
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
21
22
23 /* This file is part of the C front end.
24 It contains routines to build C expressions given their operands,
25 including computing the types of the result, C-specific error checks,
26 and some optimization. */
27
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "tm.h"
32 #include "rtl.h"
33 #include "tree.h"
34 #include "langhooks.h"
35 #include "c-tree.h"
36 #include "c-lang.h"
37 #include "tm_p.h"
38 #include "flags.h"
39 #include "output.h"
40 #include "expr.h"
41 #include "toplev.h"
42 #include "intl.h"
43 #include "ggc.h"
44 #include "target.h"
45 #include "tree-iterator.h"
46 #include "gimple.h"
47 #include "tree-flow.h"
48
49 /* Possible cases of implicit bad conversions. Used to select
50 diagnostic messages in convert_for_assignment. */
51 enum impl_conv {
52 ic_argpass,
53 ic_assign,
54 ic_init,
55 ic_return
56 };
57
58 /* Whether we are building a boolean conversion inside
59 convert_for_assignment, or some other late binary operation. If
60 build_binary_op is called (from code shared with C++) in this case,
61 then the operands have already been folded and the result will not
62 be folded again, so C_MAYBE_CONST_EXPR should not be generated. */
63 bool in_late_binary_op;
64
65 /* The level of nesting inside "__alignof__". */
66 int in_alignof;
67
68 /* The level of nesting inside "sizeof". */
69 int in_sizeof;
70
71 /* The level of nesting inside "typeof". */
72 int in_typeof;
73
74 /* Nonzero if we've already printed a "missing braces around initializer"
75 message within this initializer. */
76 static int missing_braces_mentioned;
77
78 static int require_constant_value;
79 static int require_constant_elements;
80
81 static bool null_pointer_constant_p (const_tree);
82 static tree qualify_type (tree, tree);
83 static int tagged_types_tu_compatible_p (const_tree, const_tree, bool *);
84 static int comp_target_types (location_t, tree, tree);
85 static int function_types_compatible_p (const_tree, const_tree, bool *);
86 static int type_lists_compatible_p (const_tree, const_tree, bool *);
87 static tree lookup_field (tree, tree);
88 static int convert_arguments (tree, VEC(tree,gc) *, VEC(tree,gc) *, tree,
89 tree);
90 static tree pointer_diff (location_t, tree, tree);
91 static tree convert_for_assignment (location_t, tree, tree, tree,
92 enum impl_conv, bool, tree, tree, int);
93 static tree valid_compound_expr_initializer (tree, tree);
94 static void push_string (const char *);
95 static void push_member_name (tree);
96 static int spelling_length (void);
97 static char *print_spelling (char *);
98 static void warning_init (int, const char *);
99 static tree digest_init (location_t, tree, tree, tree, bool, bool, int);
100 static void output_init_element (tree, tree, bool, tree, tree, int, bool);
101 static void output_pending_init_elements (int);
102 static int set_designator (int);
103 static void push_range_stack (tree);
104 static void add_pending_init (tree, tree, tree, bool);
105 static void set_nonincremental_init (void);
106 static void set_nonincremental_init_from_string (tree);
107 static tree find_init_member (tree);
108 static void readonly_error (tree, enum lvalue_use);
109 static void readonly_warning (tree, enum lvalue_use);
110 static int lvalue_or_else (const_tree, enum lvalue_use);
111 static void record_maybe_used_decl (tree);
112 static int comptypes_internal (const_tree, const_tree, bool *);
113 \f
114 /* Return true if EXP is a null pointer constant, false otherwise. */
115
116 static bool
117 null_pointer_constant_p (const_tree expr)
118 {
119 /* This should really operate on c_expr structures, but they aren't
120 yet available everywhere required. */
121 tree type = TREE_TYPE (expr);
122 return (TREE_CODE (expr) == INTEGER_CST
123 && !TREE_OVERFLOW (expr)
124 && integer_zerop (expr)
125 && (INTEGRAL_TYPE_P (type)
126 || (TREE_CODE (type) == POINTER_TYPE
127 && VOID_TYPE_P (TREE_TYPE (type))
128 && TYPE_QUALS (TREE_TYPE (type)) == TYPE_UNQUALIFIED)));
129 }
130
131 /* EXPR may appear in an unevaluated part of an integer constant
132 expression, but not in an evaluated part. Wrap it in a
133 C_MAYBE_CONST_EXPR, or mark it with TREE_OVERFLOW if it is just an
134 INTEGER_CST and we cannot create a C_MAYBE_CONST_EXPR. */
135
136 static tree
137 note_integer_operands (tree expr)
138 {
139 tree ret;
140 if (TREE_CODE (expr) == INTEGER_CST && in_late_binary_op)
141 {
142 ret = copy_node (expr);
143 TREE_OVERFLOW (ret) = 1;
144 }
145 else
146 {
147 ret = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (expr), NULL_TREE, expr);
148 C_MAYBE_CONST_EXPR_INT_OPERANDS (ret) = 1;
149 }
150 return ret;
151 }
152
153 /* Having checked whether EXPR may appear in an unevaluated part of an
154 integer constant expression and found that it may, remove any
155 C_MAYBE_CONST_EXPR noting this fact and return the resulting
156 expression. */
157
158 static inline tree
159 remove_c_maybe_const_expr (tree expr)
160 {
161 if (TREE_CODE (expr) == C_MAYBE_CONST_EXPR)
162 return C_MAYBE_CONST_EXPR_EXPR (expr);
163 else
164 return expr;
165 }
166
167 \f/* This is a cache to hold if two types are compatible or not. */
168
169 struct tagged_tu_seen_cache {
170 const struct tagged_tu_seen_cache * next;
171 const_tree t1;
172 const_tree t2;
173 /* The return value of tagged_types_tu_compatible_p if we had seen
174 these two types already. */
175 int val;
176 };
177
178 static const struct tagged_tu_seen_cache * tagged_tu_seen_base;
179 static void free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *);
180
181 /* Do `exp = require_complete_type (exp);' to make sure exp
182 does not have an incomplete type. (That includes void types.) */
183
184 tree
185 require_complete_type (tree value)
186 {
187 tree type = TREE_TYPE (value);
188
189 if (value == error_mark_node || type == error_mark_node)
190 return error_mark_node;
191
192 /* First, detect a valid value with a complete type. */
193 if (COMPLETE_TYPE_P (type))
194 return value;
195
196 c_incomplete_type_error (value, type);
197 return error_mark_node;
198 }
199
200 /* Print an error message for invalid use of an incomplete type.
201 VALUE is the expression that was used (or 0 if that isn't known)
202 and TYPE is the type that was invalid. */
203
204 void
205 c_incomplete_type_error (const_tree value, const_tree type)
206 {
207 const char *type_code_string;
208
209 /* Avoid duplicate error message. */
210 if (TREE_CODE (type) == ERROR_MARK)
211 return;
212
213 if (value != 0 && (TREE_CODE (value) == VAR_DECL
214 || TREE_CODE (value) == PARM_DECL))
215 error ("%qD has an incomplete type", value);
216 else
217 {
218 retry:
219 /* We must print an error message. Be clever about what it says. */
220
221 switch (TREE_CODE (type))
222 {
223 case RECORD_TYPE:
224 type_code_string = "struct";
225 break;
226
227 case UNION_TYPE:
228 type_code_string = "union";
229 break;
230
231 case ENUMERAL_TYPE:
232 type_code_string = "enum";
233 break;
234
235 case VOID_TYPE:
236 error ("invalid use of void expression");
237 return;
238
239 case ARRAY_TYPE:
240 if (TYPE_DOMAIN (type))
241 {
242 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
243 {
244 error ("invalid use of flexible array member");
245 return;
246 }
247 type = TREE_TYPE (type);
248 goto retry;
249 }
250 error ("invalid use of array with unspecified bounds");
251 return;
252
253 default:
254 gcc_unreachable ();
255 }
256
257 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
258 error ("invalid use of undefined type %<%s %E%>",
259 type_code_string, TYPE_NAME (type));
260 else
261 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
262 error ("invalid use of incomplete typedef %qD", TYPE_NAME (type));
263 }
264 }
265
266 /* Given a type, apply default promotions wrt unnamed function
267 arguments and return the new type. */
268
269 tree
270 c_type_promotes_to (tree type)
271 {
272 if (TYPE_MAIN_VARIANT (type) == float_type_node)
273 return double_type_node;
274
275 if (c_promoting_integer_type_p (type))
276 {
277 /* Preserve unsignedness if not really getting any wider. */
278 if (TYPE_UNSIGNED (type)
279 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
280 return unsigned_type_node;
281 return integer_type_node;
282 }
283
284 return type;
285 }
286
287 /* Return true if between two named address spaces, whether there is a superset
288 named address space that encompasses both address spaces. If there is a
289 superset, return which address space is the superset. */
290
291 static bool
292 addr_space_superset (addr_space_t as1, addr_space_t as2, addr_space_t *common)
293 {
294 if (as1 == as2)
295 {
296 *common = as1;
297 return true;
298 }
299 else if (targetm.addr_space.subset_p (as1, as2))
300 {
301 *common = as2;
302 return true;
303 }
304 else if (targetm.addr_space.subset_p (as2, as1))
305 {
306 *common = as1;
307 return true;
308 }
309 else
310 return false;
311 }
312
313 /* Return a variant of TYPE which has all the type qualifiers of LIKE
314 as well as those of TYPE. */
315
316 static tree
317 qualify_type (tree type, tree like)
318 {
319 addr_space_t as_type = TYPE_ADDR_SPACE (type);
320 addr_space_t as_like = TYPE_ADDR_SPACE (like);
321 addr_space_t as_common;
322
323 /* If the two named address spaces are different, determine the common
324 superset address space. If there isn't one, raise an error. */
325 if (!addr_space_superset (as_type, as_like, &as_common))
326 {
327 as_common = as_type;
328 error ("%qT and %qT are in disjoint named address spaces",
329 type, like);
330 }
331
332 return c_build_qualified_type (type,
333 TYPE_QUALS_NO_ADDR_SPACE (type)
334 | TYPE_QUALS_NO_ADDR_SPACE (like)
335 | ENCODE_QUAL_ADDR_SPACE (as_common));
336 }
337
338 /* Return true iff the given tree T is a variable length array. */
339
340 bool
341 c_vla_type_p (const_tree t)
342 {
343 if (TREE_CODE (t) == ARRAY_TYPE
344 && C_TYPE_VARIABLE_SIZE (t))
345 return true;
346 return false;
347 }
348 \f
349 /* Return the composite type of two compatible types.
350
351 We assume that comptypes has already been done and returned
352 nonzero; if that isn't so, this may crash. In particular, we
353 assume that qualifiers match. */
354
355 tree
356 composite_type (tree t1, tree t2)
357 {
358 enum tree_code code1;
359 enum tree_code code2;
360 tree attributes;
361
362 /* Save time if the two types are the same. */
363
364 if (t1 == t2) return t1;
365
366 /* If one type is nonsense, use the other. */
367 if (t1 == error_mark_node)
368 return t2;
369 if (t2 == error_mark_node)
370 return t1;
371
372 code1 = TREE_CODE (t1);
373 code2 = TREE_CODE (t2);
374
375 /* Merge the attributes. */
376 attributes = targetm.merge_type_attributes (t1, t2);
377
378 /* If one is an enumerated type and the other is the compatible
379 integer type, the composite type might be either of the two
380 (DR#013 question 3). For consistency, use the enumerated type as
381 the composite type. */
382
383 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE)
384 return t1;
385 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE)
386 return t2;
387
388 gcc_assert (code1 == code2);
389
390 switch (code1)
391 {
392 case POINTER_TYPE:
393 /* For two pointers, do this recursively on the target type. */
394 {
395 tree pointed_to_1 = TREE_TYPE (t1);
396 tree pointed_to_2 = TREE_TYPE (t2);
397 tree target = composite_type (pointed_to_1, pointed_to_2);
398 t1 = build_pointer_type (target);
399 t1 = build_type_attribute_variant (t1, attributes);
400 return qualify_type (t1, t2);
401 }
402
403 case ARRAY_TYPE:
404 {
405 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
406 int quals;
407 tree unqual_elt;
408 tree d1 = TYPE_DOMAIN (t1);
409 tree d2 = TYPE_DOMAIN (t2);
410 bool d1_variable, d2_variable;
411 bool d1_zero, d2_zero;
412 bool t1_complete, t2_complete;
413
414 /* We should not have any type quals on arrays at all. */
415 gcc_assert (!TYPE_QUALS_NO_ADDR_SPACE (t1)
416 && !TYPE_QUALS_NO_ADDR_SPACE (t2));
417
418 t1_complete = COMPLETE_TYPE_P (t1);
419 t2_complete = COMPLETE_TYPE_P (t2);
420
421 d1_zero = d1 == 0 || !TYPE_MAX_VALUE (d1);
422 d2_zero = d2 == 0 || !TYPE_MAX_VALUE (d2);
423
424 d1_variable = (!d1_zero
425 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
426 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
427 d2_variable = (!d2_zero
428 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
429 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
430 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1));
431 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2));
432
433 /* Save space: see if the result is identical to one of the args. */
434 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1)
435 && (d2_variable || d2_zero || !d1_variable))
436 return build_type_attribute_variant (t1, attributes);
437 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2)
438 && (d1_variable || d1_zero || !d2_variable))
439 return build_type_attribute_variant (t2, attributes);
440
441 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
442 return build_type_attribute_variant (t1, attributes);
443 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
444 return build_type_attribute_variant (t2, attributes);
445
446 /* Merge the element types, and have a size if either arg has
447 one. We may have qualifiers on the element types. To set
448 up TYPE_MAIN_VARIANT correctly, we need to form the
449 composite of the unqualified types and add the qualifiers
450 back at the end. */
451 quals = TYPE_QUALS (strip_array_types (elt));
452 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED);
453 t1 = build_array_type (unqual_elt,
454 TYPE_DOMAIN ((TYPE_DOMAIN (t1)
455 && (d2_variable
456 || d2_zero
457 || !d1_variable))
458 ? t1
459 : t2));
460 /* Ensure a composite type involving a zero-length array type
461 is a zero-length type not an incomplete type. */
462 if (d1_zero && d2_zero
463 && (t1_complete || t2_complete)
464 && !COMPLETE_TYPE_P (t1))
465 {
466 TYPE_SIZE (t1) = bitsize_zero_node;
467 TYPE_SIZE_UNIT (t1) = size_zero_node;
468 }
469 t1 = c_build_qualified_type (t1, quals);
470 return build_type_attribute_variant (t1, attributes);
471 }
472
473 case ENUMERAL_TYPE:
474 case RECORD_TYPE:
475 case UNION_TYPE:
476 if (attributes != NULL)
477 {
478 /* Try harder not to create a new aggregate type. */
479 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
480 return t1;
481 if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
482 return t2;
483 }
484 return build_type_attribute_variant (t1, attributes);
485
486 case FUNCTION_TYPE:
487 /* Function types: prefer the one that specified arg types.
488 If both do, merge the arg types. Also merge the return types. */
489 {
490 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
491 tree p1 = TYPE_ARG_TYPES (t1);
492 tree p2 = TYPE_ARG_TYPES (t2);
493 int len;
494 tree newargs, n;
495 int i;
496
497 /* Save space: see if the result is identical to one of the args. */
498 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2))
499 return build_type_attribute_variant (t1, attributes);
500 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1))
501 return build_type_attribute_variant (t2, attributes);
502
503 /* Simple way if one arg fails to specify argument types. */
504 if (TYPE_ARG_TYPES (t1) == 0)
505 {
506 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
507 t1 = build_type_attribute_variant (t1, attributes);
508 return qualify_type (t1, t2);
509 }
510 if (TYPE_ARG_TYPES (t2) == 0)
511 {
512 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
513 t1 = build_type_attribute_variant (t1, attributes);
514 return qualify_type (t1, t2);
515 }
516
517 /* If both args specify argument types, we must merge the two
518 lists, argument by argument. */
519 /* Tell global_bindings_p to return false so that variable_size
520 doesn't die on VLAs in parameter types. */
521 c_override_global_bindings_to_false = true;
522
523 len = list_length (p1);
524 newargs = 0;
525
526 for (i = 0; i < len; i++)
527 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
528
529 n = newargs;
530
531 for (; p1;
532 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
533 {
534 /* A null type means arg type is not specified.
535 Take whatever the other function type has. */
536 if (TREE_VALUE (p1) == 0)
537 {
538 TREE_VALUE (n) = TREE_VALUE (p2);
539 goto parm_done;
540 }
541 if (TREE_VALUE (p2) == 0)
542 {
543 TREE_VALUE (n) = TREE_VALUE (p1);
544 goto parm_done;
545 }
546
547 /* Given wait (union {union wait *u; int *i} *)
548 and wait (union wait *),
549 prefer union wait * as type of parm. */
550 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
551 && TREE_VALUE (p1) != TREE_VALUE (p2))
552 {
553 tree memb;
554 tree mv2 = TREE_VALUE (p2);
555 if (mv2 && mv2 != error_mark_node
556 && TREE_CODE (mv2) != ARRAY_TYPE)
557 mv2 = TYPE_MAIN_VARIANT (mv2);
558 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
559 memb; memb = TREE_CHAIN (memb))
560 {
561 tree mv3 = TREE_TYPE (memb);
562 if (mv3 && mv3 != error_mark_node
563 && TREE_CODE (mv3) != ARRAY_TYPE)
564 mv3 = TYPE_MAIN_VARIANT (mv3);
565 if (comptypes (mv3, mv2))
566 {
567 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
568 TREE_VALUE (p2));
569 pedwarn (input_location, OPT_pedantic,
570 "function types not truly compatible in ISO C");
571 goto parm_done;
572 }
573 }
574 }
575 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
576 && TREE_VALUE (p2) != TREE_VALUE (p1))
577 {
578 tree memb;
579 tree mv1 = TREE_VALUE (p1);
580 if (mv1 && mv1 != error_mark_node
581 && TREE_CODE (mv1) != ARRAY_TYPE)
582 mv1 = TYPE_MAIN_VARIANT (mv1);
583 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
584 memb; memb = TREE_CHAIN (memb))
585 {
586 tree mv3 = TREE_TYPE (memb);
587 if (mv3 && mv3 != error_mark_node
588 && TREE_CODE (mv3) != ARRAY_TYPE)
589 mv3 = TYPE_MAIN_VARIANT (mv3);
590 if (comptypes (mv3, mv1))
591 {
592 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
593 TREE_VALUE (p1));
594 pedwarn (input_location, OPT_pedantic,
595 "function types not truly compatible in ISO C");
596 goto parm_done;
597 }
598 }
599 }
600 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2));
601 parm_done: ;
602 }
603
604 c_override_global_bindings_to_false = false;
605 t1 = build_function_type (valtype, newargs);
606 t1 = qualify_type (t1, t2);
607 /* ... falls through ... */
608 }
609
610 default:
611 return build_type_attribute_variant (t1, attributes);
612 }
613
614 }
615
616 /* Return the type of a conditional expression between pointers to
617 possibly differently qualified versions of compatible types.
618
619 We assume that comp_target_types has already been done and returned
620 nonzero; if that isn't so, this may crash. */
621
622 static tree
623 common_pointer_type (tree t1, tree t2)
624 {
625 tree attributes;
626 tree pointed_to_1, mv1;
627 tree pointed_to_2, mv2;
628 tree target;
629 unsigned target_quals;
630 addr_space_t as1, as2, as_common;
631 int quals1, quals2;
632
633 /* Save time if the two types are the same. */
634
635 if (t1 == t2) return t1;
636
637 /* If one type is nonsense, use the other. */
638 if (t1 == error_mark_node)
639 return t2;
640 if (t2 == error_mark_node)
641 return t1;
642
643 gcc_assert (TREE_CODE (t1) == POINTER_TYPE
644 && TREE_CODE (t2) == POINTER_TYPE);
645
646 /* Merge the attributes. */
647 attributes = targetm.merge_type_attributes (t1, t2);
648
649 /* Find the composite type of the target types, and combine the
650 qualifiers of the two types' targets. Do not lose qualifiers on
651 array element types by taking the TYPE_MAIN_VARIANT. */
652 mv1 = pointed_to_1 = TREE_TYPE (t1);
653 mv2 = pointed_to_2 = TREE_TYPE (t2);
654 if (TREE_CODE (mv1) != ARRAY_TYPE)
655 mv1 = TYPE_MAIN_VARIANT (pointed_to_1);
656 if (TREE_CODE (mv2) != ARRAY_TYPE)
657 mv2 = TYPE_MAIN_VARIANT (pointed_to_2);
658 target = composite_type (mv1, mv2);
659
660 /* For function types do not merge const qualifiers, but drop them
661 if used inconsistently. The middle-end uses these to mark const
662 and noreturn functions. */
663 quals1 = TYPE_QUALS_NO_ADDR_SPACE (pointed_to_1);
664 quals2 = TYPE_QUALS_NO_ADDR_SPACE (pointed_to_2);
665
666 if (TREE_CODE (pointed_to_1) == FUNCTION_TYPE)
667 target_quals = (quals1 & quals2);
668 else
669 target_quals = (quals1 | quals2);
670
671 /* If the two named address spaces are different, determine the common
672 superset address space. This is guaranteed to exist due to the
673 assumption that comp_target_type returned non-zero. */
674 as1 = TYPE_ADDR_SPACE (pointed_to_1);
675 as2 = TYPE_ADDR_SPACE (pointed_to_2);
676 if (!addr_space_superset (as1, as2, &as_common))
677 gcc_unreachable ();
678
679 target_quals |= ENCODE_QUAL_ADDR_SPACE (as_common);
680
681 t1 = build_pointer_type (c_build_qualified_type (target, target_quals));
682 return build_type_attribute_variant (t1, attributes);
683 }
684
685 /* Return the common type for two arithmetic types under the usual
686 arithmetic conversions. The default conversions have already been
687 applied, and enumerated types converted to their compatible integer
688 types. The resulting type is unqualified and has no attributes.
689
690 This is the type for the result of most arithmetic operations
691 if the operands have the given two types. */
692
693 static tree
694 c_common_type (tree t1, tree t2)
695 {
696 enum tree_code code1;
697 enum tree_code code2;
698
699 /* If one type is nonsense, use the other. */
700 if (t1 == error_mark_node)
701 return t2;
702 if (t2 == error_mark_node)
703 return t1;
704
705 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED)
706 t1 = TYPE_MAIN_VARIANT (t1);
707
708 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED)
709 t2 = TYPE_MAIN_VARIANT (t2);
710
711 if (TYPE_ATTRIBUTES (t1) != NULL_TREE)
712 t1 = build_type_attribute_variant (t1, NULL_TREE);
713
714 if (TYPE_ATTRIBUTES (t2) != NULL_TREE)
715 t2 = build_type_attribute_variant (t2, NULL_TREE);
716
717 /* Save time if the two types are the same. */
718
719 if (t1 == t2) return t1;
720
721 code1 = TREE_CODE (t1);
722 code2 = TREE_CODE (t2);
723
724 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE
725 || code1 == FIXED_POINT_TYPE || code1 == REAL_TYPE
726 || code1 == INTEGER_TYPE);
727 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE
728 || code2 == FIXED_POINT_TYPE || code2 == REAL_TYPE
729 || code2 == INTEGER_TYPE);
730
731 /* When one operand is a decimal float type, the other operand cannot be
732 a generic float type or a complex type. We also disallow vector types
733 here. */
734 if ((DECIMAL_FLOAT_TYPE_P (t1) || DECIMAL_FLOAT_TYPE_P (t2))
735 && !(DECIMAL_FLOAT_TYPE_P (t1) && DECIMAL_FLOAT_TYPE_P (t2)))
736 {
737 if (code1 == VECTOR_TYPE || code2 == VECTOR_TYPE)
738 {
739 error ("can%'t mix operands of decimal float and vector types");
740 return error_mark_node;
741 }
742 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
743 {
744 error ("can%'t mix operands of decimal float and complex types");
745 return error_mark_node;
746 }
747 if (code1 == REAL_TYPE && code2 == REAL_TYPE)
748 {
749 error ("can%'t mix operands of decimal float and other float types");
750 return error_mark_node;
751 }
752 }
753
754 /* If one type is a vector type, return that type. (How the usual
755 arithmetic conversions apply to the vector types extension is not
756 precisely specified.) */
757 if (code1 == VECTOR_TYPE)
758 return t1;
759
760 if (code2 == VECTOR_TYPE)
761 return t2;
762
763 /* If one type is complex, form the common type of the non-complex
764 components, then make that complex. Use T1 or T2 if it is the
765 required type. */
766 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
767 {
768 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
769 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
770 tree subtype = c_common_type (subtype1, subtype2);
771
772 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
773 return t1;
774 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
775 return t2;
776 else
777 return build_complex_type (subtype);
778 }
779
780 /* If only one is real, use it as the result. */
781
782 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
783 return t1;
784
785 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
786 return t2;
787
788 /* If both are real and either are decimal floating point types, use
789 the decimal floating point type with the greater precision. */
790
791 if (code1 == REAL_TYPE && code2 == REAL_TYPE)
792 {
793 if (TYPE_MAIN_VARIANT (t1) == dfloat128_type_node
794 || TYPE_MAIN_VARIANT (t2) == dfloat128_type_node)
795 return dfloat128_type_node;
796 else if (TYPE_MAIN_VARIANT (t1) == dfloat64_type_node
797 || TYPE_MAIN_VARIANT (t2) == dfloat64_type_node)
798 return dfloat64_type_node;
799 else if (TYPE_MAIN_VARIANT (t1) == dfloat32_type_node
800 || TYPE_MAIN_VARIANT (t2) == dfloat32_type_node)
801 return dfloat32_type_node;
802 }
803
804 /* Deal with fixed-point types. */
805 if (code1 == FIXED_POINT_TYPE || code2 == FIXED_POINT_TYPE)
806 {
807 unsigned int unsignedp = 0, satp = 0;
808 enum machine_mode m1, m2;
809 unsigned int fbit1, ibit1, fbit2, ibit2, max_fbit, max_ibit;
810
811 m1 = TYPE_MODE (t1);
812 m2 = TYPE_MODE (t2);
813
814 /* If one input type is saturating, the result type is saturating. */
815 if (TYPE_SATURATING (t1) || TYPE_SATURATING (t2))
816 satp = 1;
817
818 /* If both fixed-point types are unsigned, the result type is unsigned.
819 When mixing fixed-point and integer types, follow the sign of the
820 fixed-point type.
821 Otherwise, the result type is signed. */
822 if ((TYPE_UNSIGNED (t1) && TYPE_UNSIGNED (t2)
823 && code1 == FIXED_POINT_TYPE && code2 == FIXED_POINT_TYPE)
824 || (code1 == FIXED_POINT_TYPE && code2 != FIXED_POINT_TYPE
825 && TYPE_UNSIGNED (t1))
826 || (code1 != FIXED_POINT_TYPE && code2 == FIXED_POINT_TYPE
827 && TYPE_UNSIGNED (t2)))
828 unsignedp = 1;
829
830 /* The result type is signed. */
831 if (unsignedp == 0)
832 {
833 /* If the input type is unsigned, we need to convert to the
834 signed type. */
835 if (code1 == FIXED_POINT_TYPE && TYPE_UNSIGNED (t1))
836 {
837 enum mode_class mclass = (enum mode_class) 0;
838 if (GET_MODE_CLASS (m1) == MODE_UFRACT)
839 mclass = MODE_FRACT;
840 else if (GET_MODE_CLASS (m1) == MODE_UACCUM)
841 mclass = MODE_ACCUM;
842 else
843 gcc_unreachable ();
844 m1 = mode_for_size (GET_MODE_PRECISION (m1), mclass, 0);
845 }
846 if (code2 == FIXED_POINT_TYPE && TYPE_UNSIGNED (t2))
847 {
848 enum mode_class mclass = (enum mode_class) 0;
849 if (GET_MODE_CLASS (m2) == MODE_UFRACT)
850 mclass = MODE_FRACT;
851 else if (GET_MODE_CLASS (m2) == MODE_UACCUM)
852 mclass = MODE_ACCUM;
853 else
854 gcc_unreachable ();
855 m2 = mode_for_size (GET_MODE_PRECISION (m2), mclass, 0);
856 }
857 }
858
859 if (code1 == FIXED_POINT_TYPE)
860 {
861 fbit1 = GET_MODE_FBIT (m1);
862 ibit1 = GET_MODE_IBIT (m1);
863 }
864 else
865 {
866 fbit1 = 0;
867 /* Signed integers need to subtract one sign bit. */
868 ibit1 = TYPE_PRECISION (t1) - (!TYPE_UNSIGNED (t1));
869 }
870
871 if (code2 == FIXED_POINT_TYPE)
872 {
873 fbit2 = GET_MODE_FBIT (m2);
874 ibit2 = GET_MODE_IBIT (m2);
875 }
876 else
877 {
878 fbit2 = 0;
879 /* Signed integers need to subtract one sign bit. */
880 ibit2 = TYPE_PRECISION (t2) - (!TYPE_UNSIGNED (t2));
881 }
882
883 max_ibit = ibit1 >= ibit2 ? ibit1 : ibit2;
884 max_fbit = fbit1 >= fbit2 ? fbit1 : fbit2;
885 return c_common_fixed_point_type_for_size (max_ibit, max_fbit, unsignedp,
886 satp);
887 }
888
889 /* Both real or both integers; use the one with greater precision. */
890
891 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
892 return t1;
893 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
894 return t2;
895
896 /* Same precision. Prefer long longs to longs to ints when the
897 same precision, following the C99 rules on integer type rank
898 (which are equivalent to the C90 rules for C90 types). */
899
900 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node
901 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node)
902 return long_long_unsigned_type_node;
903
904 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node
905 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node)
906 {
907 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
908 return long_long_unsigned_type_node;
909 else
910 return long_long_integer_type_node;
911 }
912
913 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
914 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
915 return long_unsigned_type_node;
916
917 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
918 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
919 {
920 /* But preserve unsignedness from the other type,
921 since long cannot hold all the values of an unsigned int. */
922 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
923 return long_unsigned_type_node;
924 else
925 return long_integer_type_node;
926 }
927
928 /* Likewise, prefer long double to double even if same size. */
929 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
930 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
931 return long_double_type_node;
932
933 /* Otherwise prefer the unsigned one. */
934
935 if (TYPE_UNSIGNED (t1))
936 return t1;
937 else
938 return t2;
939 }
940 \f
941 /* Wrapper around c_common_type that is used by c-common.c and other
942 front end optimizations that remove promotions. ENUMERAL_TYPEs
943 are allowed here and are converted to their compatible integer types.
944 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or
945 preferably a non-Boolean type as the common type. */
946 tree
947 common_type (tree t1, tree t2)
948 {
949 if (TREE_CODE (t1) == ENUMERAL_TYPE)
950 t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1);
951 if (TREE_CODE (t2) == ENUMERAL_TYPE)
952 t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1);
953
954 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */
955 if (TREE_CODE (t1) == BOOLEAN_TYPE
956 && TREE_CODE (t2) == BOOLEAN_TYPE)
957 return boolean_type_node;
958
959 /* If either type is BOOLEAN_TYPE, then return the other. */
960 if (TREE_CODE (t1) == BOOLEAN_TYPE)
961 return t2;
962 if (TREE_CODE (t2) == BOOLEAN_TYPE)
963 return t1;
964
965 return c_common_type (t1, t2);
966 }
967
968 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
969 or various other operations. Return 2 if they are compatible
970 but a warning may be needed if you use them together. */
971
972 int
973 comptypes (tree type1, tree type2)
974 {
975 const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base;
976 int val;
977
978 val = comptypes_internal (type1, type2, NULL);
979 free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1);
980
981 return val;
982 }
983
984 /* Like comptypes, but if it returns non-zero because enum and int are
985 compatible, it sets *ENUM_AND_INT_P to true. */
986
987 static int
988 comptypes_check_enum_int (tree type1, tree type2, bool *enum_and_int_p)
989 {
990 const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base;
991 int val;
992
993 val = comptypes_internal (type1, type2, enum_and_int_p);
994 free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1);
995
996 return val;
997 }
998 \f
999 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
1000 or various other operations. Return 2 if they are compatible
1001 but a warning may be needed if you use them together. If
1002 ENUM_AND_INT_P is not NULL, and one type is an enum and the other a
1003 compatible integer type, then this sets *ENUM_AND_INT_P to true;
1004 *ENUM_AND_INT_P is never set to false. This differs from
1005 comptypes, in that we don't free the seen types. */
1006
1007 static int
1008 comptypes_internal (const_tree type1, const_tree type2, bool *enum_and_int_p)
1009 {
1010 const_tree t1 = type1;
1011 const_tree t2 = type2;
1012 int attrval, val;
1013
1014 /* Suppress errors caused by previously reported errors. */
1015
1016 if (t1 == t2 || !t1 || !t2
1017 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
1018 return 1;
1019
1020 /* If either type is the internal version of sizetype, return the
1021 language version. */
1022 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
1023 && TYPE_ORIG_SIZE_TYPE (t1))
1024 t1 = TYPE_ORIG_SIZE_TYPE (t1);
1025
1026 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
1027 && TYPE_ORIG_SIZE_TYPE (t2))
1028 t2 = TYPE_ORIG_SIZE_TYPE (t2);
1029
1030
1031 /* Enumerated types are compatible with integer types, but this is
1032 not transitive: two enumerated types in the same translation unit
1033 are compatible with each other only if they are the same type. */
1034
1035 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE)
1036 {
1037 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1));
1038 if (enum_and_int_p != NULL && TREE_CODE (t2) != VOID_TYPE)
1039 *enum_and_int_p = true;
1040 }
1041 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE)
1042 {
1043 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2));
1044 if (enum_and_int_p != NULL && TREE_CODE (t1) != VOID_TYPE)
1045 *enum_and_int_p = true;
1046 }
1047
1048 if (t1 == t2)
1049 return 1;
1050
1051 /* Different classes of types can't be compatible. */
1052
1053 if (TREE_CODE (t1) != TREE_CODE (t2))
1054 return 0;
1055
1056 /* Qualifiers must match. C99 6.7.3p9 */
1057
1058 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
1059 return 0;
1060
1061 /* Allow for two different type nodes which have essentially the same
1062 definition. Note that we already checked for equality of the type
1063 qualifiers (just above). */
1064
1065 if (TREE_CODE (t1) != ARRAY_TYPE
1066 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
1067 return 1;
1068
1069 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1070 if (!(attrval = targetm.comp_type_attributes (t1, t2)))
1071 return 0;
1072
1073 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1074 val = 0;
1075
1076 switch (TREE_CODE (t1))
1077 {
1078 case POINTER_TYPE:
1079 /* Do not remove mode or aliasing information. */
1080 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1081 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
1082 break;
1083 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
1084 ? 1 : comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2),
1085 enum_and_int_p));
1086 break;
1087
1088 case FUNCTION_TYPE:
1089 val = function_types_compatible_p (t1, t2, enum_and_int_p);
1090 break;
1091
1092 case ARRAY_TYPE:
1093 {
1094 tree d1 = TYPE_DOMAIN (t1);
1095 tree d2 = TYPE_DOMAIN (t2);
1096 bool d1_variable, d2_variable;
1097 bool d1_zero, d2_zero;
1098 val = 1;
1099
1100 /* Target types must match incl. qualifiers. */
1101 if (TREE_TYPE (t1) != TREE_TYPE (t2)
1102 && 0 == (val = comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2),
1103 enum_and_int_p)))
1104 return 0;
1105
1106 /* Sizes must match unless one is missing or variable. */
1107 if (d1 == 0 || d2 == 0 || d1 == d2)
1108 break;
1109
1110 d1_zero = !TYPE_MAX_VALUE (d1);
1111 d2_zero = !TYPE_MAX_VALUE (d2);
1112
1113 d1_variable = (!d1_zero
1114 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
1115 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
1116 d2_variable = (!d2_zero
1117 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
1118 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
1119 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1));
1120 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2));
1121
1122 if (d1_variable || d2_variable)
1123 break;
1124 if (d1_zero && d2_zero)
1125 break;
1126 if (d1_zero || d2_zero
1127 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
1128 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
1129 val = 0;
1130
1131 break;
1132 }
1133
1134 case ENUMERAL_TYPE:
1135 case RECORD_TYPE:
1136 case UNION_TYPE:
1137 if (val != 1 && !same_translation_unit_p (t1, t2))
1138 {
1139 tree a1 = TYPE_ATTRIBUTES (t1);
1140 tree a2 = TYPE_ATTRIBUTES (t2);
1141
1142 if (! attribute_list_contained (a1, a2)
1143 && ! attribute_list_contained (a2, a1))
1144 break;
1145
1146 if (attrval != 2)
1147 return tagged_types_tu_compatible_p (t1, t2, enum_and_int_p);
1148 val = tagged_types_tu_compatible_p (t1, t2, enum_and_int_p);
1149 }
1150 break;
1151
1152 case VECTOR_TYPE:
1153 val = (TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
1154 && comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2),
1155 enum_and_int_p));
1156 break;
1157
1158 default:
1159 break;
1160 }
1161 return attrval == 2 && val == 1 ? 2 : val;
1162 }
1163
1164 /* Return 1 if TTL and TTR are pointers to types that are equivalent, ignoring
1165 their qualifiers, except for named address spaces. If the pointers point to
1166 different named addresses, then we must determine if one address space is a
1167 subset of the other. */
1168
1169 static int
1170 comp_target_types (location_t location, tree ttl, tree ttr)
1171 {
1172 int val;
1173 tree mvl = TREE_TYPE (ttl);
1174 tree mvr = TREE_TYPE (ttr);
1175 addr_space_t asl = TYPE_ADDR_SPACE (mvl);
1176 addr_space_t asr = TYPE_ADDR_SPACE (mvr);
1177 addr_space_t as_common;
1178 bool enum_and_int_p;
1179
1180 /* Fail if pointers point to incompatible address spaces. */
1181 if (!addr_space_superset (asl, asr, &as_common))
1182 return 0;
1183
1184 /* Do not lose qualifiers on element types of array types that are
1185 pointer targets by taking their TYPE_MAIN_VARIANT. */
1186 if (TREE_CODE (mvl) != ARRAY_TYPE)
1187 mvl = TYPE_MAIN_VARIANT (mvl);
1188 if (TREE_CODE (mvr) != ARRAY_TYPE)
1189 mvr = TYPE_MAIN_VARIANT (mvr);
1190 enum_and_int_p = false;
1191 val = comptypes_check_enum_int (mvl, mvr, &enum_and_int_p);
1192
1193 if (val == 2)
1194 pedwarn (location, OPT_pedantic, "types are not quite compatible");
1195
1196 if (val == 1 && enum_and_int_p && warn_cxx_compat)
1197 warning_at (location, OPT_Wc___compat,
1198 "pointer target types incompatible in C++");
1199
1200 return val;
1201 }
1202 \f
1203 /* Subroutines of `comptypes'. */
1204
1205 /* Determine whether two trees derive from the same translation unit.
1206 If the CONTEXT chain ends in a null, that tree's context is still
1207 being parsed, so if two trees have context chains ending in null,
1208 they're in the same translation unit. */
1209 int
1210 same_translation_unit_p (const_tree t1, const_tree t2)
1211 {
1212 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL)
1213 switch (TREE_CODE_CLASS (TREE_CODE (t1)))
1214 {
1215 case tcc_declaration:
1216 t1 = DECL_CONTEXT (t1); break;
1217 case tcc_type:
1218 t1 = TYPE_CONTEXT (t1); break;
1219 case tcc_exceptional:
1220 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */
1221 default: gcc_unreachable ();
1222 }
1223
1224 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL)
1225 switch (TREE_CODE_CLASS (TREE_CODE (t2)))
1226 {
1227 case tcc_declaration:
1228 t2 = DECL_CONTEXT (t2); break;
1229 case tcc_type:
1230 t2 = TYPE_CONTEXT (t2); break;
1231 case tcc_exceptional:
1232 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */
1233 default: gcc_unreachable ();
1234 }
1235
1236 return t1 == t2;
1237 }
1238
1239 /* Allocate the seen two types, assuming that they are compatible. */
1240
1241 static struct tagged_tu_seen_cache *
1242 alloc_tagged_tu_seen_cache (const_tree t1, const_tree t2)
1243 {
1244 struct tagged_tu_seen_cache *tu = XNEW (struct tagged_tu_seen_cache);
1245 tu->next = tagged_tu_seen_base;
1246 tu->t1 = t1;
1247 tu->t2 = t2;
1248
1249 tagged_tu_seen_base = tu;
1250
1251 /* The C standard says that two structures in different translation
1252 units are compatible with each other only if the types of their
1253 fields are compatible (among other things). We assume that they
1254 are compatible until proven otherwise when building the cache.
1255 An example where this can occur is:
1256 struct a
1257 {
1258 struct a *next;
1259 };
1260 If we are comparing this against a similar struct in another TU,
1261 and did not assume they were compatible, we end up with an infinite
1262 loop. */
1263 tu->val = 1;
1264 return tu;
1265 }
1266
1267 /* Free the seen types until we get to TU_TIL. */
1268
1269 static void
1270 free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *tu_til)
1271 {
1272 const struct tagged_tu_seen_cache *tu = tagged_tu_seen_base;
1273 while (tu != tu_til)
1274 {
1275 const struct tagged_tu_seen_cache *const tu1
1276 = (const struct tagged_tu_seen_cache *) tu;
1277 tu = tu1->next;
1278 free (CONST_CAST (struct tagged_tu_seen_cache *, tu1));
1279 }
1280 tagged_tu_seen_base = tu_til;
1281 }
1282
1283 /* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
1284 compatible. If the two types are not the same (which has been
1285 checked earlier), this can only happen when multiple translation
1286 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
1287 rules. ENUM_AND_INT_P is as in comptypes_internal. */
1288
1289 static int
1290 tagged_types_tu_compatible_p (const_tree t1, const_tree t2,
1291 bool *enum_and_int_p)
1292 {
1293 tree s1, s2;
1294 bool needs_warning = false;
1295
1296 /* We have to verify that the tags of the types are the same. This
1297 is harder than it looks because this may be a typedef, so we have
1298 to go look at the original type. It may even be a typedef of a
1299 typedef...
1300 In the case of compiler-created builtin structs the TYPE_DECL
1301 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
1302 while (TYPE_NAME (t1)
1303 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL
1304 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1)))
1305 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1));
1306
1307 while (TYPE_NAME (t2)
1308 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL
1309 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2)))
1310 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2));
1311
1312 /* C90 didn't have the requirement that the two tags be the same. */
1313 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2))
1314 return 0;
1315
1316 /* C90 didn't say what happened if one or both of the types were
1317 incomplete; we choose to follow C99 rules here, which is that they
1318 are compatible. */
1319 if (TYPE_SIZE (t1) == NULL
1320 || TYPE_SIZE (t2) == NULL)
1321 return 1;
1322
1323 {
1324 const struct tagged_tu_seen_cache * tts_i;
1325 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next)
1326 if (tts_i->t1 == t1 && tts_i->t2 == t2)
1327 return tts_i->val;
1328 }
1329
1330 switch (TREE_CODE (t1))
1331 {
1332 case ENUMERAL_TYPE:
1333 {
1334 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1335 /* Speed up the case where the type values are in the same order. */
1336 tree tv1 = TYPE_VALUES (t1);
1337 tree tv2 = TYPE_VALUES (t2);
1338
1339 if (tv1 == tv2)
1340 {
1341 return 1;
1342 }
1343
1344 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2))
1345 {
1346 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2))
1347 break;
1348 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1)
1349 {
1350 tu->val = 0;
1351 return 0;
1352 }
1353 }
1354
1355 if (tv1 == NULL_TREE && tv2 == NULL_TREE)
1356 {
1357 return 1;
1358 }
1359 if (tv1 == NULL_TREE || tv2 == NULL_TREE)
1360 {
1361 tu->val = 0;
1362 return 0;
1363 }
1364
1365 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2)))
1366 {
1367 tu->val = 0;
1368 return 0;
1369 }
1370
1371 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1))
1372 {
1373 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2));
1374 if (s2 == NULL
1375 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1)
1376 {
1377 tu->val = 0;
1378 return 0;
1379 }
1380 }
1381 return 1;
1382 }
1383
1384 case UNION_TYPE:
1385 {
1386 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1387 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2)))
1388 {
1389 tu->val = 0;
1390 return 0;
1391 }
1392
1393 /* Speed up the common case where the fields are in the same order. */
1394 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2); s1 && s2;
1395 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1396 {
1397 int result;
1398
1399 if (DECL_NAME (s1) != DECL_NAME (s2))
1400 break;
1401 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2),
1402 enum_and_int_p);
1403
1404 if (result != 1 && !DECL_NAME (s1))
1405 break;
1406 if (result == 0)
1407 {
1408 tu->val = 0;
1409 return 0;
1410 }
1411 if (result == 2)
1412 needs_warning = true;
1413
1414 if (TREE_CODE (s1) == FIELD_DECL
1415 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1416 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1417 {
1418 tu->val = 0;
1419 return 0;
1420 }
1421 }
1422 if (!s1 && !s2)
1423 {
1424 tu->val = needs_warning ? 2 : 1;
1425 return tu->val;
1426 }
1427
1428 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1))
1429 {
1430 bool ok = false;
1431
1432 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2))
1433 if (DECL_NAME (s1) == DECL_NAME (s2))
1434 {
1435 int result;
1436
1437 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2),
1438 enum_and_int_p);
1439
1440 if (result != 1 && !DECL_NAME (s1))
1441 continue;
1442 if (result == 0)
1443 {
1444 tu->val = 0;
1445 return 0;
1446 }
1447 if (result == 2)
1448 needs_warning = true;
1449
1450 if (TREE_CODE (s1) == FIELD_DECL
1451 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1452 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1453 break;
1454
1455 ok = true;
1456 break;
1457 }
1458 if (!ok)
1459 {
1460 tu->val = 0;
1461 return 0;
1462 }
1463 }
1464 tu->val = needs_warning ? 2 : 10;
1465 return tu->val;
1466 }
1467
1468 case RECORD_TYPE:
1469 {
1470 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1471
1472 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2);
1473 s1 && s2;
1474 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1475 {
1476 int result;
1477 if (TREE_CODE (s1) != TREE_CODE (s2)
1478 || DECL_NAME (s1) != DECL_NAME (s2))
1479 break;
1480 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2),
1481 enum_and_int_p);
1482 if (result == 0)
1483 break;
1484 if (result == 2)
1485 needs_warning = true;
1486
1487 if (TREE_CODE (s1) == FIELD_DECL
1488 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1489 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1490 break;
1491 }
1492 if (s1 && s2)
1493 tu->val = 0;
1494 else
1495 tu->val = needs_warning ? 2 : 1;
1496 return tu->val;
1497 }
1498
1499 default:
1500 gcc_unreachable ();
1501 }
1502 }
1503
1504 /* Return 1 if two function types F1 and F2 are compatible.
1505 If either type specifies no argument types,
1506 the other must specify a fixed number of self-promoting arg types.
1507 Otherwise, if one type specifies only the number of arguments,
1508 the other must specify that number of self-promoting arg types.
1509 Otherwise, the argument types must match.
1510 ENUM_AND_INT_P is as in comptypes_internal. */
1511
1512 static int
1513 function_types_compatible_p (const_tree f1, const_tree f2,
1514 bool *enum_and_int_p)
1515 {
1516 tree args1, args2;
1517 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1518 int val = 1;
1519 int val1;
1520 tree ret1, ret2;
1521
1522 ret1 = TREE_TYPE (f1);
1523 ret2 = TREE_TYPE (f2);
1524
1525 /* 'volatile' qualifiers on a function's return type used to mean
1526 the function is noreturn. */
1527 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2))
1528 pedwarn (input_location, 0, "function return types not compatible due to %<volatile%>");
1529 if (TYPE_VOLATILE (ret1))
1530 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1),
1531 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE);
1532 if (TYPE_VOLATILE (ret2))
1533 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2),
1534 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE);
1535 val = comptypes_internal (ret1, ret2, enum_and_int_p);
1536 if (val == 0)
1537 return 0;
1538
1539 args1 = TYPE_ARG_TYPES (f1);
1540 args2 = TYPE_ARG_TYPES (f2);
1541
1542 /* An unspecified parmlist matches any specified parmlist
1543 whose argument types don't need default promotions. */
1544
1545 if (args1 == 0)
1546 {
1547 if (!self_promoting_args_p (args2))
1548 return 0;
1549 /* If one of these types comes from a non-prototype fn definition,
1550 compare that with the other type's arglist.
1551 If they don't match, ask for a warning (but no error). */
1552 if (TYPE_ACTUAL_ARG_TYPES (f1)
1553 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1),
1554 enum_and_int_p))
1555 val = 2;
1556 return val;
1557 }
1558 if (args2 == 0)
1559 {
1560 if (!self_promoting_args_p (args1))
1561 return 0;
1562 if (TYPE_ACTUAL_ARG_TYPES (f2)
1563 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2),
1564 enum_and_int_p))
1565 val = 2;
1566 return val;
1567 }
1568
1569 /* Both types have argument lists: compare them and propagate results. */
1570 val1 = type_lists_compatible_p (args1, args2, enum_and_int_p);
1571 return val1 != 1 ? val1 : val;
1572 }
1573
1574 /* Check two lists of types for compatibility, returning 0 for
1575 incompatible, 1 for compatible, or 2 for compatible with
1576 warning. ENUM_AND_INT_P is as in comptypes_internal. */
1577
1578 static int
1579 type_lists_compatible_p (const_tree args1, const_tree args2,
1580 bool *enum_and_int_p)
1581 {
1582 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1583 int val = 1;
1584 int newval = 0;
1585
1586 while (1)
1587 {
1588 tree a1, mv1, a2, mv2;
1589 if (args1 == 0 && args2 == 0)
1590 return val;
1591 /* If one list is shorter than the other,
1592 they fail to match. */
1593 if (args1 == 0 || args2 == 0)
1594 return 0;
1595 mv1 = a1 = TREE_VALUE (args1);
1596 mv2 = a2 = TREE_VALUE (args2);
1597 if (mv1 && mv1 != error_mark_node && TREE_CODE (mv1) != ARRAY_TYPE)
1598 mv1 = TYPE_MAIN_VARIANT (mv1);
1599 if (mv2 && mv2 != error_mark_node && TREE_CODE (mv2) != ARRAY_TYPE)
1600 mv2 = TYPE_MAIN_VARIANT (mv2);
1601 /* A null pointer instead of a type
1602 means there is supposed to be an argument
1603 but nothing is specified about what type it has.
1604 So match anything that self-promotes. */
1605 if (a1 == 0)
1606 {
1607 if (c_type_promotes_to (a2) != a2)
1608 return 0;
1609 }
1610 else if (a2 == 0)
1611 {
1612 if (c_type_promotes_to (a1) != a1)
1613 return 0;
1614 }
1615 /* If one of the lists has an error marker, ignore this arg. */
1616 else if (TREE_CODE (a1) == ERROR_MARK
1617 || TREE_CODE (a2) == ERROR_MARK)
1618 ;
1619 else if (!(newval = comptypes_internal (mv1, mv2, enum_and_int_p)))
1620 {
1621 /* Allow wait (union {union wait *u; int *i} *)
1622 and wait (union wait *) to be compatible. */
1623 if (TREE_CODE (a1) == UNION_TYPE
1624 && (TYPE_NAME (a1) == 0
1625 || TYPE_TRANSPARENT_AGGR (a1))
1626 && TREE_CODE (TYPE_SIZE (a1)) == INTEGER_CST
1627 && tree_int_cst_equal (TYPE_SIZE (a1),
1628 TYPE_SIZE (a2)))
1629 {
1630 tree memb;
1631 for (memb = TYPE_FIELDS (a1);
1632 memb; memb = TREE_CHAIN (memb))
1633 {
1634 tree mv3 = TREE_TYPE (memb);
1635 if (mv3 && mv3 != error_mark_node
1636 && TREE_CODE (mv3) != ARRAY_TYPE)
1637 mv3 = TYPE_MAIN_VARIANT (mv3);
1638 if (comptypes_internal (mv3, mv2, enum_and_int_p))
1639 break;
1640 }
1641 if (memb == 0)
1642 return 0;
1643 }
1644 else if (TREE_CODE (a2) == UNION_TYPE
1645 && (TYPE_NAME (a2) == 0
1646 || TYPE_TRANSPARENT_AGGR (a2))
1647 && TREE_CODE (TYPE_SIZE (a2)) == INTEGER_CST
1648 && tree_int_cst_equal (TYPE_SIZE (a2),
1649 TYPE_SIZE (a1)))
1650 {
1651 tree memb;
1652 for (memb = TYPE_FIELDS (a2);
1653 memb; memb = TREE_CHAIN (memb))
1654 {
1655 tree mv3 = TREE_TYPE (memb);
1656 if (mv3 && mv3 != error_mark_node
1657 && TREE_CODE (mv3) != ARRAY_TYPE)
1658 mv3 = TYPE_MAIN_VARIANT (mv3);
1659 if (comptypes_internal (mv3, mv1, enum_and_int_p))
1660 break;
1661 }
1662 if (memb == 0)
1663 return 0;
1664 }
1665 else
1666 return 0;
1667 }
1668
1669 /* comptypes said ok, but record if it said to warn. */
1670 if (newval > val)
1671 val = newval;
1672
1673 args1 = TREE_CHAIN (args1);
1674 args2 = TREE_CHAIN (args2);
1675 }
1676 }
1677 \f
1678 /* Compute the size to increment a pointer by. */
1679
1680 static tree
1681 c_size_in_bytes (const_tree type)
1682 {
1683 enum tree_code code = TREE_CODE (type);
1684
1685 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
1686 return size_one_node;
1687
1688 if (!COMPLETE_OR_VOID_TYPE_P (type))
1689 {
1690 error ("arithmetic on pointer to an incomplete type");
1691 return size_one_node;
1692 }
1693
1694 /* Convert in case a char is more than one unit. */
1695 return size_binop_loc (input_location, CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
1696 size_int (TYPE_PRECISION (char_type_node)
1697 / BITS_PER_UNIT));
1698 }
1699 \f
1700 /* Return either DECL or its known constant value (if it has one). */
1701
1702 tree
1703 decl_constant_value (tree decl)
1704 {
1705 if (/* Don't change a variable array bound or initial value to a constant
1706 in a place where a variable is invalid. Note that DECL_INITIAL
1707 isn't valid for a PARM_DECL. */
1708 current_function_decl != 0
1709 && TREE_CODE (decl) != PARM_DECL
1710 && !TREE_THIS_VOLATILE (decl)
1711 && TREE_READONLY (decl)
1712 && DECL_INITIAL (decl) != 0
1713 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
1714 /* This is invalid if initial value is not constant.
1715 If it has either a function call, a memory reference,
1716 or a variable, then re-evaluating it could give different results. */
1717 && TREE_CONSTANT (DECL_INITIAL (decl))
1718 /* Check for cases where this is sub-optimal, even though valid. */
1719 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
1720 return DECL_INITIAL (decl);
1721 return decl;
1722 }
1723
1724 /* Convert the array expression EXP to a pointer. */
1725 static tree
1726 array_to_pointer_conversion (location_t loc, tree exp)
1727 {
1728 tree orig_exp = exp;
1729 tree type = TREE_TYPE (exp);
1730 tree adr;
1731 tree restype = TREE_TYPE (type);
1732 tree ptrtype;
1733
1734 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
1735
1736 STRIP_TYPE_NOPS (exp);
1737
1738 if (TREE_NO_WARNING (orig_exp))
1739 TREE_NO_WARNING (exp) = 1;
1740
1741 ptrtype = build_pointer_type (restype);
1742
1743 if (TREE_CODE (exp) == INDIRECT_REF)
1744 return convert (ptrtype, TREE_OPERAND (exp, 0));
1745
1746 adr = build_unary_op (loc, ADDR_EXPR, exp, 1);
1747 return convert (ptrtype, adr);
1748 }
1749
1750 /* Convert the function expression EXP to a pointer. */
1751 static tree
1752 function_to_pointer_conversion (location_t loc, tree exp)
1753 {
1754 tree orig_exp = exp;
1755
1756 gcc_assert (TREE_CODE (TREE_TYPE (exp)) == FUNCTION_TYPE);
1757
1758 STRIP_TYPE_NOPS (exp);
1759
1760 if (TREE_NO_WARNING (orig_exp))
1761 TREE_NO_WARNING (exp) = 1;
1762
1763 return build_unary_op (loc, ADDR_EXPR, exp, 0);
1764 }
1765
1766 /* Perform the default conversion of arrays and functions to pointers.
1767 Return the result of converting EXP. For any other expression, just
1768 return EXP.
1769
1770 LOC is the location of the expression. */
1771
1772 struct c_expr
1773 default_function_array_conversion (location_t loc, struct c_expr exp)
1774 {
1775 tree orig_exp = exp.value;
1776 tree type = TREE_TYPE (exp.value);
1777 enum tree_code code = TREE_CODE (type);
1778
1779 switch (code)
1780 {
1781 case ARRAY_TYPE:
1782 {
1783 bool not_lvalue = false;
1784 bool lvalue_array_p;
1785
1786 while ((TREE_CODE (exp.value) == NON_LVALUE_EXPR
1787 || CONVERT_EXPR_P (exp.value))
1788 && TREE_TYPE (TREE_OPERAND (exp.value, 0)) == type)
1789 {
1790 if (TREE_CODE (exp.value) == NON_LVALUE_EXPR)
1791 not_lvalue = true;
1792 exp.value = TREE_OPERAND (exp.value, 0);
1793 }
1794
1795 if (TREE_NO_WARNING (orig_exp))
1796 TREE_NO_WARNING (exp.value) = 1;
1797
1798 lvalue_array_p = !not_lvalue && lvalue_p (exp.value);
1799 if (!flag_isoc99 && !lvalue_array_p)
1800 {
1801 /* Before C99, non-lvalue arrays do not decay to pointers.
1802 Normally, using such an array would be invalid; but it can
1803 be used correctly inside sizeof or as a statement expression.
1804 Thus, do not give an error here; an error will result later. */
1805 return exp;
1806 }
1807
1808 exp.value = array_to_pointer_conversion (loc, exp.value);
1809 }
1810 break;
1811 case FUNCTION_TYPE:
1812 exp.value = function_to_pointer_conversion (loc, exp.value);
1813 break;
1814 default:
1815 break;
1816 }
1817
1818 return exp;
1819 }
1820
1821
1822 /* EXP is an expression of integer type. Apply the integer promotions
1823 to it and return the promoted value. */
1824
1825 tree
1826 perform_integral_promotions (tree exp)
1827 {
1828 tree type = TREE_TYPE (exp);
1829 enum tree_code code = TREE_CODE (type);
1830
1831 gcc_assert (INTEGRAL_TYPE_P (type));
1832
1833 /* Normally convert enums to int,
1834 but convert wide enums to something wider. */
1835 if (code == ENUMERAL_TYPE)
1836 {
1837 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
1838 TYPE_PRECISION (integer_type_node)),
1839 ((TYPE_PRECISION (type)
1840 >= TYPE_PRECISION (integer_type_node))
1841 && TYPE_UNSIGNED (type)));
1842
1843 return convert (type, exp);
1844 }
1845
1846 /* ??? This should no longer be needed now bit-fields have their
1847 proper types. */
1848 if (TREE_CODE (exp) == COMPONENT_REF
1849 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
1850 /* If it's thinner than an int, promote it like a
1851 c_promoting_integer_type_p, otherwise leave it alone. */
1852 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
1853 TYPE_PRECISION (integer_type_node)))
1854 return convert (integer_type_node, exp);
1855
1856 if (c_promoting_integer_type_p (type))
1857 {
1858 /* Preserve unsignedness if not really getting any wider. */
1859 if (TYPE_UNSIGNED (type)
1860 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1861 return convert (unsigned_type_node, exp);
1862
1863 return convert (integer_type_node, exp);
1864 }
1865
1866 return exp;
1867 }
1868
1869
1870 /* Perform default promotions for C data used in expressions.
1871 Enumeral types or short or char are converted to int.
1872 In addition, manifest constants symbols are replaced by their values. */
1873
1874 tree
1875 default_conversion (tree exp)
1876 {
1877 tree orig_exp;
1878 tree type = TREE_TYPE (exp);
1879 enum tree_code code = TREE_CODE (type);
1880 tree promoted_type;
1881
1882 /* Functions and arrays have been converted during parsing. */
1883 gcc_assert (code != FUNCTION_TYPE);
1884 if (code == ARRAY_TYPE)
1885 return exp;
1886
1887 /* Constants can be used directly unless they're not loadable. */
1888 if (TREE_CODE (exp) == CONST_DECL)
1889 exp = DECL_INITIAL (exp);
1890
1891 /* Strip no-op conversions. */
1892 orig_exp = exp;
1893 STRIP_TYPE_NOPS (exp);
1894
1895 if (TREE_NO_WARNING (orig_exp))
1896 TREE_NO_WARNING (exp) = 1;
1897
1898 if (code == VOID_TYPE)
1899 {
1900 error ("void value not ignored as it ought to be");
1901 return error_mark_node;
1902 }
1903
1904 exp = require_complete_type (exp);
1905 if (exp == error_mark_node)
1906 return error_mark_node;
1907
1908 promoted_type = targetm.promoted_type (type);
1909 if (promoted_type)
1910 return convert (promoted_type, exp);
1911
1912 if (INTEGRAL_TYPE_P (type))
1913 return perform_integral_promotions (exp);
1914
1915 return exp;
1916 }
1917 \f
1918 /* Look up COMPONENT in a structure or union DECL.
1919
1920 If the component name is not found, returns NULL_TREE. Otherwise,
1921 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1922 stepping down the chain to the component, which is in the last
1923 TREE_VALUE of the list. Normally the list is of length one, but if
1924 the component is embedded within (nested) anonymous structures or
1925 unions, the list steps down the chain to the component. */
1926
1927 static tree
1928 lookup_field (tree decl, tree component)
1929 {
1930 tree type = TREE_TYPE (decl);
1931 tree field;
1932
1933 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1934 to the field elements. Use a binary search on this array to quickly
1935 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1936 will always be set for structures which have many elements. */
1937
1938 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s)
1939 {
1940 int bot, top, half;
1941 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0];
1942
1943 field = TYPE_FIELDS (type);
1944 bot = 0;
1945 top = TYPE_LANG_SPECIFIC (type)->s->len;
1946 while (top - bot > 1)
1947 {
1948 half = (top - bot + 1) >> 1;
1949 field = field_array[bot+half];
1950
1951 if (DECL_NAME (field) == NULL_TREE)
1952 {
1953 /* Step through all anon unions in linear fashion. */
1954 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1955 {
1956 field = field_array[bot++];
1957 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1958 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1959 {
1960 tree anon = lookup_field (field, component);
1961
1962 if (anon)
1963 return tree_cons (NULL_TREE, field, anon);
1964 }
1965 }
1966
1967 /* Entire record is only anon unions. */
1968 if (bot > top)
1969 return NULL_TREE;
1970
1971 /* Restart the binary search, with new lower bound. */
1972 continue;
1973 }
1974
1975 if (DECL_NAME (field) == component)
1976 break;
1977 if (DECL_NAME (field) < component)
1978 bot += half;
1979 else
1980 top = bot + half;
1981 }
1982
1983 if (DECL_NAME (field_array[bot]) == component)
1984 field = field_array[bot];
1985 else if (DECL_NAME (field) != component)
1986 return NULL_TREE;
1987 }
1988 else
1989 {
1990 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1991 {
1992 if (DECL_NAME (field) == NULL_TREE
1993 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1994 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
1995 {
1996 tree anon = lookup_field (field, component);
1997
1998 if (anon)
1999 return tree_cons (NULL_TREE, field, anon);
2000 }
2001
2002 if (DECL_NAME (field) == component)
2003 break;
2004 }
2005
2006 if (field == NULL_TREE)
2007 return NULL_TREE;
2008 }
2009
2010 return tree_cons (NULL_TREE, field, NULL_TREE);
2011 }
2012
2013 /* Make an expression to refer to the COMPONENT field of structure or
2014 union value DATUM. COMPONENT is an IDENTIFIER_NODE. LOC is the
2015 location of the COMPONENT_REF. */
2016
2017 tree
2018 build_component_ref (location_t loc, tree datum, tree component)
2019 {
2020 tree type = TREE_TYPE (datum);
2021 enum tree_code code = TREE_CODE (type);
2022 tree field = NULL;
2023 tree ref;
2024 bool datum_lvalue = lvalue_p (datum);
2025
2026 if (!objc_is_public (datum, component))
2027 return error_mark_node;
2028
2029 /* See if there is a field or component with name COMPONENT. */
2030
2031 if (code == RECORD_TYPE || code == UNION_TYPE)
2032 {
2033 if (!COMPLETE_TYPE_P (type))
2034 {
2035 c_incomplete_type_error (NULL_TREE, type);
2036 return error_mark_node;
2037 }
2038
2039 field = lookup_field (datum, component);
2040
2041 if (!field)
2042 {
2043 error_at (loc, "%qT has no member named %qE", type, component);
2044 return error_mark_node;
2045 }
2046
2047 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
2048 This might be better solved in future the way the C++ front
2049 end does it - by giving the anonymous entities each a
2050 separate name and type, and then have build_component_ref
2051 recursively call itself. We can't do that here. */
2052 do
2053 {
2054 tree subdatum = TREE_VALUE (field);
2055 int quals;
2056 tree subtype;
2057 bool use_datum_quals;
2058
2059 if (TREE_TYPE (subdatum) == error_mark_node)
2060 return error_mark_node;
2061
2062 /* If this is an rvalue, it does not have qualifiers in C
2063 standard terms and we must avoid propagating such
2064 qualifiers down to a non-lvalue array that is then
2065 converted to a pointer. */
2066 use_datum_quals = (datum_lvalue
2067 || TREE_CODE (TREE_TYPE (subdatum)) != ARRAY_TYPE);
2068
2069 quals = TYPE_QUALS (strip_array_types (TREE_TYPE (subdatum)));
2070 if (use_datum_quals)
2071 quals |= TYPE_QUALS (TREE_TYPE (datum));
2072 subtype = c_build_qualified_type (TREE_TYPE (subdatum), quals);
2073
2074 ref = build3 (COMPONENT_REF, subtype, datum, subdatum,
2075 NULL_TREE);
2076 SET_EXPR_LOCATION (ref, loc);
2077 if (TREE_READONLY (subdatum)
2078 || (use_datum_quals && TREE_READONLY (datum)))
2079 TREE_READONLY (ref) = 1;
2080 if (TREE_THIS_VOLATILE (subdatum)
2081 || (use_datum_quals && TREE_THIS_VOLATILE (datum)))
2082 TREE_THIS_VOLATILE (ref) = 1;
2083
2084 if (TREE_DEPRECATED (subdatum))
2085 warn_deprecated_use (subdatum, NULL_TREE);
2086
2087 datum = ref;
2088
2089 field = TREE_CHAIN (field);
2090 }
2091 while (field);
2092
2093 return ref;
2094 }
2095 else if (code != ERROR_MARK)
2096 error_at (loc,
2097 "request for member %qE in something not a structure or union",
2098 component);
2099
2100 return error_mark_node;
2101 }
2102 \f
2103 /* Given an expression PTR for a pointer, return an expression
2104 for the value pointed to.
2105 ERRORSTRING is the name of the operator to appear in error messages.
2106
2107 LOC is the location to use for the generated tree. */
2108
2109 tree
2110 build_indirect_ref (location_t loc, tree ptr, ref_operator errstring)
2111 {
2112 tree pointer = default_conversion (ptr);
2113 tree type = TREE_TYPE (pointer);
2114 tree ref;
2115
2116 if (TREE_CODE (type) == POINTER_TYPE)
2117 {
2118 if (CONVERT_EXPR_P (pointer)
2119 || TREE_CODE (pointer) == VIEW_CONVERT_EXPR)
2120 {
2121 /* If a warning is issued, mark it to avoid duplicates from
2122 the backend. This only needs to be done at
2123 warn_strict_aliasing > 2. */
2124 if (warn_strict_aliasing > 2)
2125 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (pointer, 0)),
2126 type, TREE_OPERAND (pointer, 0)))
2127 TREE_NO_WARNING (pointer) = 1;
2128 }
2129
2130 if (TREE_CODE (pointer) == ADDR_EXPR
2131 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
2132 == TREE_TYPE (type)))
2133 {
2134 ref = TREE_OPERAND (pointer, 0);
2135 protected_set_expr_location (ref, loc);
2136 return ref;
2137 }
2138 else
2139 {
2140 tree t = TREE_TYPE (type);
2141
2142 ref = build1 (INDIRECT_REF, t, pointer);
2143
2144 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
2145 {
2146 error_at (loc, "dereferencing pointer to incomplete type");
2147 return error_mark_node;
2148 }
2149 if (VOID_TYPE_P (t) && c_inhibit_evaluation_warnings == 0)
2150 warning_at (loc, 0, "dereferencing %<void *%> pointer");
2151
2152 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2153 so that we get the proper error message if the result is used
2154 to assign to. Also, &* is supposed to be a no-op.
2155 And ANSI C seems to specify that the type of the result
2156 should be the const type. */
2157 /* A de-reference of a pointer to const is not a const. It is valid
2158 to change it via some other pointer. */
2159 TREE_READONLY (ref) = TYPE_READONLY (t);
2160 TREE_SIDE_EFFECTS (ref)
2161 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
2162 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
2163 protected_set_expr_location (ref, loc);
2164 return ref;
2165 }
2166 }
2167 else if (TREE_CODE (pointer) != ERROR_MARK)
2168 switch (errstring)
2169 {
2170 case RO_ARRAY_INDEXING:
2171 error_at (loc,
2172 "invalid type argument of array indexing (have %qT)",
2173 type);
2174 break;
2175 case RO_UNARY_STAR:
2176 error_at (loc,
2177 "invalid type argument of unary %<*%> (have %qT)",
2178 type);
2179 break;
2180 case RO_ARROW:
2181 error_at (loc,
2182 "invalid type argument of %<->%> (have %qT)",
2183 type);
2184 break;
2185 default:
2186 gcc_unreachable ();
2187 }
2188 return error_mark_node;
2189 }
2190
2191 /* This handles expressions of the form "a[i]", which denotes
2192 an array reference.
2193
2194 This is logically equivalent in C to *(a+i), but we may do it differently.
2195 If A is a variable or a member, we generate a primitive ARRAY_REF.
2196 This avoids forcing the array out of registers, and can work on
2197 arrays that are not lvalues (for example, members of structures returned
2198 by functions).
2199
2200 LOC is the location to use for the returned expression. */
2201
2202 tree
2203 build_array_ref (location_t loc, tree array, tree index)
2204 {
2205 tree ret;
2206 bool swapped = false;
2207 if (TREE_TYPE (array) == error_mark_node
2208 || TREE_TYPE (index) == error_mark_node)
2209 return error_mark_node;
2210
2211 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE
2212 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE)
2213 {
2214 tree temp;
2215 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE
2216 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE)
2217 {
2218 error_at (loc, "subscripted value is neither array nor pointer");
2219 return error_mark_node;
2220 }
2221 temp = array;
2222 array = index;
2223 index = temp;
2224 swapped = true;
2225 }
2226
2227 if (!INTEGRAL_TYPE_P (TREE_TYPE (index)))
2228 {
2229 error_at (loc, "array subscript is not an integer");
2230 return error_mark_node;
2231 }
2232
2233 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE)
2234 {
2235 error_at (loc, "subscripted value is pointer to function");
2236 return error_mark_node;
2237 }
2238
2239 /* ??? Existing practice has been to warn only when the char
2240 index is syntactically the index, not for char[array]. */
2241 if (!swapped)
2242 warn_array_subscript_with_type_char (index);
2243
2244 /* Apply default promotions *after* noticing character types. */
2245 index = default_conversion (index);
2246
2247 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE);
2248
2249 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2250 {
2251 tree rval, type;
2252
2253 /* An array that is indexed by a non-constant
2254 cannot be stored in a register; we must be able to do
2255 address arithmetic on its address.
2256 Likewise an array of elements of variable size. */
2257 if (TREE_CODE (index) != INTEGER_CST
2258 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2259 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
2260 {
2261 if (!c_mark_addressable (array))
2262 return error_mark_node;
2263 }
2264 /* An array that is indexed by a constant value which is not within
2265 the array bounds cannot be stored in a register either; because we
2266 would get a crash in store_bit_field/extract_bit_field when trying
2267 to access a non-existent part of the register. */
2268 if (TREE_CODE (index) == INTEGER_CST
2269 && TYPE_DOMAIN (TREE_TYPE (array))
2270 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
2271 {
2272 if (!c_mark_addressable (array))
2273 return error_mark_node;
2274 }
2275
2276 if (pedantic)
2277 {
2278 tree foo = array;
2279 while (TREE_CODE (foo) == COMPONENT_REF)
2280 foo = TREE_OPERAND (foo, 0);
2281 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
2282 pedwarn (loc, OPT_pedantic,
2283 "ISO C forbids subscripting %<register%> array");
2284 else if (!flag_isoc99 && !lvalue_p (foo))
2285 pedwarn (loc, OPT_pedantic,
2286 "ISO C90 forbids subscripting non-lvalue array");
2287 }
2288
2289 type = TREE_TYPE (TREE_TYPE (array));
2290 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE);
2291 /* Array ref is const/volatile if the array elements are
2292 or if the array is. */
2293 TREE_READONLY (rval)
2294 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
2295 | TREE_READONLY (array));
2296 TREE_SIDE_EFFECTS (rval)
2297 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2298 | TREE_SIDE_EFFECTS (array));
2299 TREE_THIS_VOLATILE (rval)
2300 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2301 /* This was added by rms on 16 Nov 91.
2302 It fixes vol struct foo *a; a->elts[1]
2303 in an inline function.
2304 Hope it doesn't break something else. */
2305 | TREE_THIS_VOLATILE (array));
2306 ret = require_complete_type (rval);
2307 protected_set_expr_location (ret, loc);
2308 return ret;
2309 }
2310 else
2311 {
2312 tree ar = default_conversion (array);
2313
2314 if (ar == error_mark_node)
2315 return ar;
2316
2317 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE);
2318 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE);
2319
2320 return build_indirect_ref
2321 (loc, build_binary_op (loc, PLUS_EXPR, ar, index, 0),
2322 RO_ARRAY_INDEXING);
2323 }
2324 }
2325 \f
2326 /* Build an external reference to identifier ID. FUN indicates
2327 whether this will be used for a function call. LOC is the source
2328 location of the identifier. This sets *TYPE to the type of the
2329 identifier, which is not the same as the type of the returned value
2330 for CONST_DECLs defined as enum constants. If the type of the
2331 identifier is not available, *TYPE is set to NULL. */
2332 tree
2333 build_external_ref (location_t loc, tree id, int fun, tree *type)
2334 {
2335 tree ref;
2336 tree decl = lookup_name (id);
2337
2338 /* In Objective-C, an instance variable (ivar) may be preferred to
2339 whatever lookup_name() found. */
2340 decl = objc_lookup_ivar (decl, id);
2341
2342 *type = NULL;
2343 if (decl && decl != error_mark_node)
2344 {
2345 ref = decl;
2346 *type = TREE_TYPE (ref);
2347 }
2348 else if (fun)
2349 /* Implicit function declaration. */
2350 ref = implicitly_declare (loc, id);
2351 else if (decl == error_mark_node)
2352 /* Don't complain about something that's already been
2353 complained about. */
2354 return error_mark_node;
2355 else
2356 {
2357 undeclared_variable (loc, id);
2358 return error_mark_node;
2359 }
2360
2361 if (TREE_TYPE (ref) == error_mark_node)
2362 return error_mark_node;
2363
2364 if (TREE_DEPRECATED (ref))
2365 warn_deprecated_use (ref, NULL_TREE);
2366
2367 /* Recursive call does not count as usage. */
2368 if (ref != current_function_decl)
2369 {
2370 TREE_USED (ref) = 1;
2371 }
2372
2373 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof)
2374 {
2375 if (!in_sizeof && !in_typeof)
2376 C_DECL_USED (ref) = 1;
2377 else if (DECL_INITIAL (ref) == 0
2378 && DECL_EXTERNAL (ref)
2379 && !TREE_PUBLIC (ref))
2380 record_maybe_used_decl (ref);
2381 }
2382
2383 if (TREE_CODE (ref) == CONST_DECL)
2384 {
2385 used_types_insert (TREE_TYPE (ref));
2386
2387 if (warn_cxx_compat
2388 && TREE_CODE (TREE_TYPE (ref)) == ENUMERAL_TYPE
2389 && C_TYPE_DEFINED_IN_STRUCT (TREE_TYPE (ref)))
2390 {
2391 warning_at (loc, OPT_Wc___compat,
2392 ("enum constant defined in struct or union "
2393 "is not visible in C++"));
2394 inform (DECL_SOURCE_LOCATION (ref), "enum constant defined here");
2395 }
2396
2397 ref = DECL_INITIAL (ref);
2398 TREE_CONSTANT (ref) = 1;
2399 }
2400 else if (current_function_decl != 0
2401 && !DECL_FILE_SCOPE_P (current_function_decl)
2402 && (TREE_CODE (ref) == VAR_DECL
2403 || TREE_CODE (ref) == PARM_DECL
2404 || TREE_CODE (ref) == FUNCTION_DECL))
2405 {
2406 tree context = decl_function_context (ref);
2407
2408 if (context != 0 && context != current_function_decl)
2409 DECL_NONLOCAL (ref) = 1;
2410 }
2411 /* C99 6.7.4p3: An inline definition of a function with external
2412 linkage ... shall not contain a reference to an identifier with
2413 internal linkage. */
2414 else if (current_function_decl != 0
2415 && DECL_DECLARED_INLINE_P (current_function_decl)
2416 && DECL_EXTERNAL (current_function_decl)
2417 && VAR_OR_FUNCTION_DECL_P (ref)
2418 && (TREE_CODE (ref) != VAR_DECL || TREE_STATIC (ref))
2419 && ! TREE_PUBLIC (ref)
2420 && DECL_CONTEXT (ref) != current_function_decl)
2421 record_inline_static (loc, current_function_decl, ref,
2422 csi_internal);
2423
2424 return ref;
2425 }
2426
2427 /* Record details of decls possibly used inside sizeof or typeof. */
2428 struct maybe_used_decl
2429 {
2430 /* The decl. */
2431 tree decl;
2432 /* The level seen at (in_sizeof + in_typeof). */
2433 int level;
2434 /* The next one at this level or above, or NULL. */
2435 struct maybe_used_decl *next;
2436 };
2437
2438 static struct maybe_used_decl *maybe_used_decls;
2439
2440 /* Record that DECL, an undefined static function reference seen
2441 inside sizeof or typeof, might be used if the operand of sizeof is
2442 a VLA type or the operand of typeof is a variably modified
2443 type. */
2444
2445 static void
2446 record_maybe_used_decl (tree decl)
2447 {
2448 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl);
2449 t->decl = decl;
2450 t->level = in_sizeof + in_typeof;
2451 t->next = maybe_used_decls;
2452 maybe_used_decls = t;
2453 }
2454
2455 /* Pop the stack of decls possibly used inside sizeof or typeof. If
2456 USED is false, just discard them. If it is true, mark them used
2457 (if no longer inside sizeof or typeof) or move them to the next
2458 level up (if still inside sizeof or typeof). */
2459
2460 void
2461 pop_maybe_used (bool used)
2462 {
2463 struct maybe_used_decl *p = maybe_used_decls;
2464 int cur_level = in_sizeof + in_typeof;
2465 while (p && p->level > cur_level)
2466 {
2467 if (used)
2468 {
2469 if (cur_level == 0)
2470 C_DECL_USED (p->decl) = 1;
2471 else
2472 p->level = cur_level;
2473 }
2474 p = p->next;
2475 }
2476 if (!used || cur_level == 0)
2477 maybe_used_decls = p;
2478 }
2479
2480 /* Return the result of sizeof applied to EXPR. */
2481
2482 struct c_expr
2483 c_expr_sizeof_expr (location_t loc, struct c_expr expr)
2484 {
2485 struct c_expr ret;
2486 if (expr.value == error_mark_node)
2487 {
2488 ret.value = error_mark_node;
2489 ret.original_code = ERROR_MARK;
2490 ret.original_type = NULL;
2491 pop_maybe_used (false);
2492 }
2493 else
2494 {
2495 bool expr_const_operands = true;
2496 tree folded_expr = c_fully_fold (expr.value, require_constant_value,
2497 &expr_const_operands);
2498 ret.value = c_sizeof (loc, TREE_TYPE (folded_expr));
2499 ret.original_code = ERROR_MARK;
2500 ret.original_type = NULL;
2501 if (c_vla_type_p (TREE_TYPE (folded_expr)))
2502 {
2503 /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */
2504 ret.value = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (ret.value),
2505 folded_expr, ret.value);
2506 C_MAYBE_CONST_EXPR_NON_CONST (ret.value) = !expr_const_operands;
2507 SET_EXPR_LOCATION (ret.value, loc);
2508 }
2509 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (folded_expr)));
2510 }
2511 return ret;
2512 }
2513
2514 /* Return the result of sizeof applied to T, a structure for the type
2515 name passed to sizeof (rather than the type itself). LOC is the
2516 location of the original expression. */
2517
2518 struct c_expr
2519 c_expr_sizeof_type (location_t loc, struct c_type_name *t)
2520 {
2521 tree type;
2522 struct c_expr ret;
2523 tree type_expr = NULL_TREE;
2524 bool type_expr_const = true;
2525 type = groktypename (t, &type_expr, &type_expr_const);
2526 ret.value = c_sizeof (loc, type);
2527 ret.original_code = ERROR_MARK;
2528 ret.original_type = NULL;
2529 if ((type_expr || TREE_CODE (ret.value) == INTEGER_CST)
2530 && c_vla_type_p (type))
2531 {
2532 /* If the type is a [*] array, it is a VLA but is represented as
2533 having a size of zero. In such a case we must ensure that
2534 the result of sizeof does not get folded to a constant by
2535 c_fully_fold, because if the size is evaluated the result is
2536 not constant and so constraints on zero or negative size
2537 arrays must not be applied when this sizeof call is inside
2538 another array declarator. */
2539 if (!type_expr)
2540 type_expr = integer_zero_node;
2541 ret.value = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (ret.value),
2542 type_expr, ret.value);
2543 C_MAYBE_CONST_EXPR_NON_CONST (ret.value) = !type_expr_const;
2544 }
2545 pop_maybe_used (type != error_mark_node
2546 ? C_TYPE_VARIABLE_SIZE (type) : false);
2547 return ret;
2548 }
2549
2550 /* Build a function call to function FUNCTION with parameters PARAMS.
2551 The function call is at LOC.
2552 PARAMS is a list--a chain of TREE_LIST nodes--in which the
2553 TREE_VALUE of each node is a parameter-expression.
2554 FUNCTION's data type may be a function type or a pointer-to-function. */
2555
2556 tree
2557 build_function_call (location_t loc, tree function, tree params)
2558 {
2559 VEC(tree,gc) *vec;
2560 tree ret;
2561
2562 vec = VEC_alloc (tree, gc, list_length (params));
2563 for (; params; params = TREE_CHAIN (params))
2564 VEC_quick_push (tree, vec, TREE_VALUE (params));
2565 ret = build_function_call_vec (loc, function, vec, NULL);
2566 VEC_free (tree, gc, vec);
2567 return ret;
2568 }
2569
2570 /* Build a function call to function FUNCTION with parameters PARAMS.
2571 ORIGTYPES, if not NULL, is a vector of types; each element is
2572 either NULL or the original type of the corresponding element in
2573 PARAMS. The original type may differ from TREE_TYPE of the
2574 parameter for enums. FUNCTION's data type may be a function type
2575 or pointer-to-function. This function changes the elements of
2576 PARAMS. */
2577
2578 tree
2579 build_function_call_vec (location_t loc, tree function, VEC(tree,gc) *params,
2580 VEC(tree,gc) *origtypes)
2581 {
2582 tree fntype, fundecl = 0;
2583 tree name = NULL_TREE, result;
2584 tree tem;
2585 int nargs;
2586 tree *argarray;
2587
2588
2589 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2590 STRIP_TYPE_NOPS (function);
2591
2592 /* Convert anything with function type to a pointer-to-function. */
2593 if (TREE_CODE (function) == FUNCTION_DECL)
2594 {
2595 /* Implement type-directed function overloading for builtins.
2596 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin
2597 handle all the type checking. The result is a complete expression
2598 that implements this function call. */
2599 tem = resolve_overloaded_builtin (loc, function, params);
2600 if (tem)
2601 return tem;
2602
2603 name = DECL_NAME (function);
2604 fundecl = function;
2605 }
2606 if (TREE_CODE (TREE_TYPE (function)) == FUNCTION_TYPE)
2607 function = function_to_pointer_conversion (loc, function);
2608
2609 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2610 expressions, like those used for ObjC messenger dispatches. */
2611 if (!VEC_empty (tree, params))
2612 function = objc_rewrite_function_call (function,
2613 VEC_index (tree, params, 0));
2614
2615 function = c_fully_fold (function, false, NULL);
2616
2617 fntype = TREE_TYPE (function);
2618
2619 if (TREE_CODE (fntype) == ERROR_MARK)
2620 return error_mark_node;
2621
2622 if (!(TREE_CODE (fntype) == POINTER_TYPE
2623 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
2624 {
2625 error_at (loc, "called object %qE is not a function", function);
2626 return error_mark_node;
2627 }
2628
2629 if (fundecl && TREE_THIS_VOLATILE (fundecl))
2630 current_function_returns_abnormally = 1;
2631
2632 /* fntype now gets the type of function pointed to. */
2633 fntype = TREE_TYPE (fntype);
2634
2635 /* Convert the parameters to the types declared in the
2636 function prototype, or apply default promotions. */
2637
2638 nargs = convert_arguments (TYPE_ARG_TYPES (fntype), params, origtypes,
2639 function, fundecl);
2640 if (nargs < 0)
2641 return error_mark_node;
2642
2643 /* Check that the function is called through a compatible prototype.
2644 If it is not, replace the call by a trap, wrapped up in a compound
2645 expression if necessary. This has the nice side-effect to prevent
2646 the tree-inliner from generating invalid assignment trees which may
2647 blow up in the RTL expander later. */
2648 if (CONVERT_EXPR_P (function)
2649 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
2650 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
2651 && !comptypes (fntype, TREE_TYPE (tem)))
2652 {
2653 tree return_type = TREE_TYPE (fntype);
2654 tree trap = build_function_call (loc, built_in_decls[BUILT_IN_TRAP],
2655 NULL_TREE);
2656 int i;
2657
2658 /* This situation leads to run-time undefined behavior. We can't,
2659 therefore, simply error unless we can prove that all possible
2660 executions of the program must execute the code. */
2661 if (warning_at (loc, 0, "function called through a non-compatible type"))
2662 /* We can, however, treat "undefined" any way we please.
2663 Call abort to encourage the user to fix the program. */
2664 inform (loc, "if this code is reached, the program will abort");
2665 /* Before the abort, allow the function arguments to exit or
2666 call longjmp. */
2667 for (i = 0; i < nargs; i++)
2668 trap = build2 (COMPOUND_EXPR, void_type_node,
2669 VEC_index (tree, params, i), trap);
2670
2671 if (VOID_TYPE_P (return_type))
2672 {
2673 if (TYPE_QUALS (return_type) != TYPE_UNQUALIFIED)
2674 pedwarn (loc, 0,
2675 "function with qualified void return type called");
2676 return trap;
2677 }
2678 else
2679 {
2680 tree rhs;
2681
2682 if (AGGREGATE_TYPE_P (return_type))
2683 rhs = build_compound_literal (loc, return_type,
2684 build_constructor (return_type, 0),
2685 false);
2686 else
2687 rhs = fold_convert_loc (loc, return_type, integer_zero_node);
2688
2689 return require_complete_type (build2 (COMPOUND_EXPR, return_type,
2690 trap, rhs));
2691 }
2692 }
2693
2694 argarray = VEC_address (tree, params);
2695
2696 /* Check that arguments to builtin functions match the expectations. */
2697 if (fundecl
2698 && DECL_BUILT_IN (fundecl)
2699 && DECL_BUILT_IN_CLASS (fundecl) == BUILT_IN_NORMAL
2700 && !check_builtin_function_arguments (fundecl, nargs, argarray))
2701 return error_mark_node;
2702
2703 /* Check that the arguments to the function are valid. */
2704 check_function_arguments (TYPE_ATTRIBUTES (fntype), nargs, argarray,
2705 TYPE_ARG_TYPES (fntype));
2706
2707 if (name != NULL_TREE
2708 && !strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10))
2709 {
2710 if (require_constant_value)
2711 result =
2712 fold_build_call_array_initializer_loc (loc, TREE_TYPE (fntype),
2713 function, nargs, argarray);
2714 else
2715 result = fold_build_call_array_loc (loc, TREE_TYPE (fntype),
2716 function, nargs, argarray);
2717 if (TREE_CODE (result) == NOP_EXPR
2718 && TREE_CODE (TREE_OPERAND (result, 0)) == INTEGER_CST)
2719 STRIP_TYPE_NOPS (result);
2720 }
2721 else
2722 result = build_call_array_loc (loc, TREE_TYPE (fntype),
2723 function, nargs, argarray);
2724
2725 if (VOID_TYPE_P (TREE_TYPE (result)))
2726 {
2727 if (TYPE_QUALS (TREE_TYPE (result)) != TYPE_UNQUALIFIED)
2728 pedwarn (loc, 0,
2729 "function with qualified void return type called");
2730 return result;
2731 }
2732 return require_complete_type (result);
2733 }
2734 \f
2735 /* Convert the argument expressions in the vector VALUES
2736 to the types in the list TYPELIST.
2737
2738 If TYPELIST is exhausted, or when an element has NULL as its type,
2739 perform the default conversions.
2740
2741 ORIGTYPES is the original types of the expressions in VALUES. This
2742 holds the type of enum values which have been converted to integral
2743 types. It may be NULL.
2744
2745 FUNCTION is a tree for the called function. It is used only for
2746 error messages, where it is formatted with %qE.
2747
2748 This is also where warnings about wrong number of args are generated.
2749
2750 Returns the actual number of arguments processed (which may be less
2751 than the length of VALUES in some error situations), or -1 on
2752 failure. */
2753
2754 static int
2755 convert_arguments (tree typelist, VEC(tree,gc) *values,
2756 VEC(tree,gc) *origtypes, tree function, tree fundecl)
2757 {
2758 tree typetail, val;
2759 unsigned int parmnum;
2760 bool error_args = false;
2761 const bool type_generic = fundecl
2762 && lookup_attribute ("type generic", TYPE_ATTRIBUTES(TREE_TYPE (fundecl)));
2763 bool type_generic_remove_excess_precision = false;
2764 tree selector;
2765
2766 /* Change pointer to function to the function itself for
2767 diagnostics. */
2768 if (TREE_CODE (function) == ADDR_EXPR
2769 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
2770 function = TREE_OPERAND (function, 0);
2771
2772 /* Handle an ObjC selector specially for diagnostics. */
2773 selector = objc_message_selector ();
2774
2775 /* For type-generic built-in functions, determine whether excess
2776 precision should be removed (classification) or not
2777 (comparison). */
2778 if (type_generic
2779 && DECL_BUILT_IN (fundecl)
2780 && DECL_BUILT_IN_CLASS (fundecl) == BUILT_IN_NORMAL)
2781 {
2782 switch (DECL_FUNCTION_CODE (fundecl))
2783 {
2784 case BUILT_IN_ISFINITE:
2785 case BUILT_IN_ISINF:
2786 case BUILT_IN_ISINF_SIGN:
2787 case BUILT_IN_ISNAN:
2788 case BUILT_IN_ISNORMAL:
2789 case BUILT_IN_FPCLASSIFY:
2790 type_generic_remove_excess_precision = true;
2791 break;
2792
2793 default:
2794 type_generic_remove_excess_precision = false;
2795 break;
2796 }
2797 }
2798
2799 /* Scan the given expressions and types, producing individual
2800 converted arguments. */
2801
2802 for (typetail = typelist, parmnum = 0;
2803 VEC_iterate (tree, values, parmnum, val);
2804 ++parmnum)
2805 {
2806 tree type = typetail ? TREE_VALUE (typetail) : 0;
2807 tree valtype = TREE_TYPE (val);
2808 tree rname = function;
2809 int argnum = parmnum + 1;
2810 const char *invalid_func_diag;
2811 bool excess_precision = false;
2812 bool npc;
2813 tree parmval;
2814
2815 if (type == void_type_node)
2816 {
2817 error_at (input_location,
2818 "too many arguments to function %qE", function);
2819 if (fundecl && !DECL_BUILT_IN (fundecl))
2820 inform (DECL_SOURCE_LOCATION (fundecl), "declared here");
2821 return parmnum;
2822 }
2823
2824 if (selector && argnum > 2)
2825 {
2826 rname = selector;
2827 argnum -= 2;
2828 }
2829
2830 npc = null_pointer_constant_p (val);
2831
2832 /* If there is excess precision and a prototype, convert once to
2833 the required type rather than converting via the semantic
2834 type. Likewise without a prototype a float value represented
2835 as long double should be converted once to double. But for
2836 type-generic classification functions excess precision must
2837 be removed here. */
2838 if (TREE_CODE (val) == EXCESS_PRECISION_EXPR
2839 && (type || !type_generic || !type_generic_remove_excess_precision))
2840 {
2841 val = TREE_OPERAND (val, 0);
2842 excess_precision = true;
2843 }
2844 val = c_fully_fold (val, false, NULL);
2845 STRIP_TYPE_NOPS (val);
2846
2847 val = require_complete_type (val);
2848
2849 if (type != 0)
2850 {
2851 /* Formal parm type is specified by a function prototype. */
2852
2853 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
2854 {
2855 error ("type of formal parameter %d is incomplete", parmnum + 1);
2856 parmval = val;
2857 }
2858 else
2859 {
2860 tree origtype;
2861
2862 /* Optionally warn about conversions that
2863 differ from the default conversions. */
2864 if (warn_traditional_conversion || warn_traditional)
2865 {
2866 unsigned int formal_prec = TYPE_PRECISION (type);
2867
2868 if (INTEGRAL_TYPE_P (type)
2869 && TREE_CODE (valtype) == REAL_TYPE)
2870 warning (0, "passing argument %d of %qE as integer "
2871 "rather than floating due to prototype",
2872 argnum, rname);
2873 if (INTEGRAL_TYPE_P (type)
2874 && TREE_CODE (valtype) == COMPLEX_TYPE)
2875 warning (0, "passing argument %d of %qE as integer "
2876 "rather than complex due to prototype",
2877 argnum, rname);
2878 else if (TREE_CODE (type) == COMPLEX_TYPE
2879 && TREE_CODE (valtype) == REAL_TYPE)
2880 warning (0, "passing argument %d of %qE as complex "
2881 "rather than floating due to prototype",
2882 argnum, rname);
2883 else if (TREE_CODE (type) == REAL_TYPE
2884 && INTEGRAL_TYPE_P (valtype))
2885 warning (0, "passing argument %d of %qE as floating "
2886 "rather than integer due to prototype",
2887 argnum, rname);
2888 else if (TREE_CODE (type) == COMPLEX_TYPE
2889 && INTEGRAL_TYPE_P (valtype))
2890 warning (0, "passing argument %d of %qE as complex "
2891 "rather than integer due to prototype",
2892 argnum, rname);
2893 else if (TREE_CODE (type) == REAL_TYPE
2894 && TREE_CODE (valtype) == COMPLEX_TYPE)
2895 warning (0, "passing argument %d of %qE as floating "
2896 "rather than complex due to prototype",
2897 argnum, rname);
2898 /* ??? At some point, messages should be written about
2899 conversions between complex types, but that's too messy
2900 to do now. */
2901 else if (TREE_CODE (type) == REAL_TYPE
2902 && TREE_CODE (valtype) == REAL_TYPE)
2903 {
2904 /* Warn if any argument is passed as `float',
2905 since without a prototype it would be `double'. */
2906 if (formal_prec == TYPE_PRECISION (float_type_node)
2907 && type != dfloat32_type_node)
2908 warning (0, "passing argument %d of %qE as %<float%> "
2909 "rather than %<double%> due to prototype",
2910 argnum, rname);
2911
2912 /* Warn if mismatch between argument and prototype
2913 for decimal float types. Warn of conversions with
2914 binary float types and of precision narrowing due to
2915 prototype. */
2916 else if (type != valtype
2917 && (type == dfloat32_type_node
2918 || type == dfloat64_type_node
2919 || type == dfloat128_type_node
2920 || valtype == dfloat32_type_node
2921 || valtype == dfloat64_type_node
2922 || valtype == dfloat128_type_node)
2923 && (formal_prec
2924 <= TYPE_PRECISION (valtype)
2925 || (type == dfloat128_type_node
2926 && (valtype
2927 != dfloat64_type_node
2928 && (valtype
2929 != dfloat32_type_node)))
2930 || (type == dfloat64_type_node
2931 && (valtype
2932 != dfloat32_type_node))))
2933 warning (0, "passing argument %d of %qE as %qT "
2934 "rather than %qT due to prototype",
2935 argnum, rname, type, valtype);
2936
2937 }
2938 /* Detect integer changing in width or signedness.
2939 These warnings are only activated with
2940 -Wtraditional-conversion, not with -Wtraditional. */
2941 else if (warn_traditional_conversion && INTEGRAL_TYPE_P (type)
2942 && INTEGRAL_TYPE_P (valtype))
2943 {
2944 tree would_have_been = default_conversion (val);
2945 tree type1 = TREE_TYPE (would_have_been);
2946
2947 if (TREE_CODE (type) == ENUMERAL_TYPE
2948 && (TYPE_MAIN_VARIANT (type)
2949 == TYPE_MAIN_VARIANT (valtype)))
2950 /* No warning if function asks for enum
2951 and the actual arg is that enum type. */
2952 ;
2953 else if (formal_prec != TYPE_PRECISION (type1))
2954 warning (OPT_Wtraditional_conversion,
2955 "passing argument %d of %qE "
2956 "with different width due to prototype",
2957 argnum, rname);
2958 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2959 ;
2960 /* Don't complain if the formal parameter type
2961 is an enum, because we can't tell now whether
2962 the value was an enum--even the same enum. */
2963 else if (TREE_CODE (type) == ENUMERAL_TYPE)
2964 ;
2965 else if (TREE_CODE (val) == INTEGER_CST
2966 && int_fits_type_p (val, type))
2967 /* Change in signedness doesn't matter
2968 if a constant value is unaffected. */
2969 ;
2970 /* If the value is extended from a narrower
2971 unsigned type, it doesn't matter whether we
2972 pass it as signed or unsigned; the value
2973 certainly is the same either way. */
2974 else if (TYPE_PRECISION (valtype) < TYPE_PRECISION (type)
2975 && TYPE_UNSIGNED (valtype))
2976 ;
2977 else if (TYPE_UNSIGNED (type))
2978 warning (OPT_Wtraditional_conversion,
2979 "passing argument %d of %qE "
2980 "as unsigned due to prototype",
2981 argnum, rname);
2982 else
2983 warning (OPT_Wtraditional_conversion,
2984 "passing argument %d of %qE "
2985 "as signed due to prototype", argnum, rname);
2986 }
2987 }
2988
2989 /* Possibly restore an EXCESS_PRECISION_EXPR for the
2990 sake of better warnings from convert_and_check. */
2991 if (excess_precision)
2992 val = build1 (EXCESS_PRECISION_EXPR, valtype, val);
2993 origtype = (origtypes == NULL
2994 ? NULL_TREE
2995 : VEC_index (tree, origtypes, parmnum));
2996 parmval = convert_for_assignment (input_location, type, val,
2997 origtype, ic_argpass, npc,
2998 fundecl, function,
2999 parmnum + 1);
3000
3001 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
3002 && INTEGRAL_TYPE_P (type)
3003 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
3004 parmval = default_conversion (parmval);
3005 }
3006 }
3007 else if (TREE_CODE (valtype) == REAL_TYPE
3008 && (TYPE_PRECISION (valtype)
3009 < TYPE_PRECISION (double_type_node))
3010 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (valtype)))
3011 {
3012 if (type_generic)
3013 parmval = val;
3014 else
3015 /* Convert `float' to `double'. */
3016 parmval = convert (double_type_node, val);
3017 }
3018 else if (excess_precision && !type_generic)
3019 /* A "double" argument with excess precision being passed
3020 without a prototype or in variable arguments. */
3021 parmval = convert (valtype, val);
3022 else if ((invalid_func_diag =
3023 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val)))
3024 {
3025 error (invalid_func_diag);
3026 return -1;
3027 }
3028 else
3029 /* Convert `short' and `char' to full-size `int'. */
3030 parmval = default_conversion (val);
3031
3032 VEC_replace (tree, values, parmnum, parmval);
3033 if (parmval == error_mark_node)
3034 error_args = true;
3035
3036 if (typetail)
3037 typetail = TREE_CHAIN (typetail);
3038 }
3039
3040 gcc_assert (parmnum == VEC_length (tree, values));
3041
3042 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
3043 {
3044 error_at (input_location,
3045 "too few arguments to function %qE", function);
3046 if (fundecl && !DECL_BUILT_IN (fundecl))
3047 inform (DECL_SOURCE_LOCATION (fundecl), "declared here");
3048 return -1;
3049 }
3050
3051 return error_args ? -1 : (int) parmnum;
3052 }
3053 \f
3054 /* This is the entry point used by the parser to build unary operators
3055 in the input. CODE, a tree_code, specifies the unary operator, and
3056 ARG is the operand. For unary plus, the C parser currently uses
3057 CONVERT_EXPR for code.
3058
3059 LOC is the location to use for the tree generated.
3060 */
3061
3062 struct c_expr
3063 parser_build_unary_op (location_t loc, enum tree_code code, struct c_expr arg)
3064 {
3065 struct c_expr result;
3066
3067 result.value = build_unary_op (loc, code, arg.value, 0);
3068 result.original_code = code;
3069 result.original_type = NULL;
3070
3071 if (TREE_OVERFLOW_P (result.value) && !TREE_OVERFLOW_P (arg.value))
3072 overflow_warning (loc, result.value);
3073
3074 return result;
3075 }
3076
3077 /* This is the entry point used by the parser to build binary operators
3078 in the input. CODE, a tree_code, specifies the binary operator, and
3079 ARG1 and ARG2 are the operands. In addition to constructing the
3080 expression, we check for operands that were written with other binary
3081 operators in a way that is likely to confuse the user.
3082
3083 LOCATION is the location of the binary operator. */
3084
3085 struct c_expr
3086 parser_build_binary_op (location_t location, enum tree_code code,
3087 struct c_expr arg1, struct c_expr arg2)
3088 {
3089 struct c_expr result;
3090
3091 enum tree_code code1 = arg1.original_code;
3092 enum tree_code code2 = arg2.original_code;
3093 tree type1 = (arg1.original_type
3094 ? arg1.original_type
3095 : TREE_TYPE (arg1.value));
3096 tree type2 = (arg2.original_type
3097 ? arg2.original_type
3098 : TREE_TYPE (arg2.value));
3099
3100 result.value = build_binary_op (location, code,
3101 arg1.value, arg2.value, 1);
3102 result.original_code = code;
3103 result.original_type = NULL;
3104
3105 if (TREE_CODE (result.value) == ERROR_MARK)
3106 return result;
3107
3108 if (location != UNKNOWN_LOCATION)
3109 protected_set_expr_location (result.value, location);
3110
3111 /* Check for cases such as x+y<<z which users are likely
3112 to misinterpret. */
3113 if (warn_parentheses)
3114 warn_about_parentheses (code, code1, arg1.value, code2, arg2.value);
3115
3116 if (warn_logical_op)
3117 warn_logical_operator (input_location, code, TREE_TYPE (result.value),
3118 code1, arg1.value, code2, arg2.value);
3119
3120 /* Warn about comparisons against string literals, with the exception
3121 of testing for equality or inequality of a string literal with NULL. */
3122 if (code == EQ_EXPR || code == NE_EXPR)
3123 {
3124 if ((code1 == STRING_CST && !integer_zerop (arg2.value))
3125 || (code2 == STRING_CST && !integer_zerop (arg1.value)))
3126 warning_at (location, OPT_Waddress,
3127 "comparison with string literal results in unspecified behavior");
3128 }
3129 else if (TREE_CODE_CLASS (code) == tcc_comparison
3130 && (code1 == STRING_CST || code2 == STRING_CST))
3131 warning_at (location, OPT_Waddress,
3132 "comparison with string literal results in unspecified behavior");
3133
3134 if (TREE_OVERFLOW_P (result.value)
3135 && !TREE_OVERFLOW_P (arg1.value)
3136 && !TREE_OVERFLOW_P (arg2.value))
3137 overflow_warning (location, result.value);
3138
3139 /* Warn about comparisons of different enum types. */
3140 if (warn_enum_compare
3141 && TREE_CODE_CLASS (code) == tcc_comparison
3142 && TREE_CODE (type1) == ENUMERAL_TYPE
3143 && TREE_CODE (type2) == ENUMERAL_TYPE
3144 && TYPE_MAIN_VARIANT (type1) != TYPE_MAIN_VARIANT (type2))
3145 warning_at (location, OPT_Wenum_compare,
3146 "comparison between %qT and %qT",
3147 type1, type2);
3148
3149 return result;
3150 }
3151 \f
3152 /* Return a tree for the difference of pointers OP0 and OP1.
3153 The resulting tree has type int. */
3154
3155 static tree
3156 pointer_diff (location_t loc, tree op0, tree op1)
3157 {
3158 tree restype = ptrdiff_type_node;
3159 tree result, inttype;
3160
3161 addr_space_t as0 = TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (op0)));
3162 addr_space_t as1 = TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (op1)));
3163 tree target_type = TREE_TYPE (TREE_TYPE (op0));
3164 tree con0, con1, lit0, lit1;
3165 tree orig_op1 = op1;
3166
3167 /* If the operands point into different address spaces, we need to
3168 explicitly convert them to pointers into the common address space
3169 before we can subtract the numerical address values. */
3170 if (as0 != as1)
3171 {
3172 addr_space_t as_common;
3173 tree common_type;
3174
3175 /* Determine the common superset address space. This is guaranteed
3176 to exist because the caller verified that comp_target_types
3177 returned non-zero. */
3178 if (!addr_space_superset (as0, as1, &as_common))
3179 gcc_unreachable ();
3180
3181 common_type = common_pointer_type (TREE_TYPE (op0), TREE_TYPE (op1));
3182 op0 = convert (common_type, op0);
3183 op1 = convert (common_type, op1);
3184 }
3185
3186 /* Determine integer type to perform computations in. This will usually
3187 be the same as the result type (ptrdiff_t), but may need to be a wider
3188 type if pointers for the address space are wider than ptrdiff_t. */
3189 if (TYPE_PRECISION (restype) < TYPE_PRECISION (TREE_TYPE (op0)))
3190 inttype = lang_hooks.types.type_for_size
3191 (TYPE_PRECISION (TREE_TYPE (op0)), 0);
3192 else
3193 inttype = restype;
3194
3195
3196 if (TREE_CODE (target_type) == VOID_TYPE)
3197 pedwarn (loc, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
3198 "pointer of type %<void *%> used in subtraction");
3199 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3200 pedwarn (loc, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
3201 "pointer to a function used in subtraction");
3202
3203 /* If the conversion to ptrdiff_type does anything like widening or
3204 converting a partial to an integral mode, we get a convert_expression
3205 that is in the way to do any simplifications.
3206 (fold-const.c doesn't know that the extra bits won't be needed.
3207 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
3208 different mode in place.)
3209 So first try to find a common term here 'by hand'; we want to cover
3210 at least the cases that occur in legal static initializers. */
3211 if (CONVERT_EXPR_P (op0)
3212 && (TYPE_PRECISION (TREE_TYPE (op0))
3213 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
3214 con0 = TREE_OPERAND (op0, 0);
3215 else
3216 con0 = op0;
3217 if (CONVERT_EXPR_P (op1)
3218 && (TYPE_PRECISION (TREE_TYPE (op1))
3219 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))))
3220 con1 = TREE_OPERAND (op1, 0);
3221 else
3222 con1 = op1;
3223
3224 if (TREE_CODE (con0) == PLUS_EXPR)
3225 {
3226 lit0 = TREE_OPERAND (con0, 1);
3227 con0 = TREE_OPERAND (con0, 0);
3228 }
3229 else
3230 lit0 = integer_zero_node;
3231
3232 if (TREE_CODE (con1) == PLUS_EXPR)
3233 {
3234 lit1 = TREE_OPERAND (con1, 1);
3235 con1 = TREE_OPERAND (con1, 0);
3236 }
3237 else
3238 lit1 = integer_zero_node;
3239
3240 if (operand_equal_p (con0, con1, 0))
3241 {
3242 op0 = lit0;
3243 op1 = lit1;
3244 }
3245
3246
3247 /* First do the subtraction as integers;
3248 then drop through to build the divide operator.
3249 Do not do default conversions on the minus operator
3250 in case restype is a short type. */
3251
3252 op0 = build_binary_op (loc,
3253 MINUS_EXPR, convert (inttype, op0),
3254 convert (inttype, op1), 0);
3255 /* This generates an error if op1 is pointer to incomplete type. */
3256 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
3257 error_at (loc, "arithmetic on pointer to an incomplete type");
3258
3259 /* This generates an error if op0 is pointer to incomplete type. */
3260 op1 = c_size_in_bytes (target_type);
3261
3262 /* Divide by the size, in easiest possible way. */
3263 result = fold_build2_loc (loc, EXACT_DIV_EXPR, inttype,
3264 op0, convert (inttype, op1));
3265
3266 /* Convert to final result type if necessary. */
3267 return convert (restype, result);
3268 }
3269 \f
3270 /* Construct and perhaps optimize a tree representation
3271 for a unary operation. CODE, a tree_code, specifies the operation
3272 and XARG is the operand.
3273 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
3274 the default promotions (such as from short to int).
3275 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
3276 allows non-lvalues; this is only used to handle conversion of non-lvalue
3277 arrays to pointers in C99.
3278
3279 LOCATION is the location of the operator. */
3280
3281 tree
3282 build_unary_op (location_t location,
3283 enum tree_code code, tree xarg, int flag)
3284 {
3285 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3286 tree arg = xarg;
3287 tree argtype = 0;
3288 enum tree_code typecode;
3289 tree val;
3290 tree ret = error_mark_node;
3291 tree eptype = NULL_TREE;
3292 int noconvert = flag;
3293 const char *invalid_op_diag;
3294 bool int_operands;
3295
3296 int_operands = EXPR_INT_CONST_OPERANDS (xarg);
3297 if (int_operands)
3298 arg = remove_c_maybe_const_expr (arg);
3299
3300 if (code != ADDR_EXPR)
3301 arg = require_complete_type (arg);
3302
3303 typecode = TREE_CODE (TREE_TYPE (arg));
3304 if (typecode == ERROR_MARK)
3305 return error_mark_node;
3306 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
3307 typecode = INTEGER_TYPE;
3308
3309 if ((invalid_op_diag
3310 = targetm.invalid_unary_op (code, TREE_TYPE (xarg))))
3311 {
3312 error_at (location, invalid_op_diag);
3313 return error_mark_node;
3314 }
3315
3316 if (TREE_CODE (arg) == EXCESS_PRECISION_EXPR)
3317 {
3318 eptype = TREE_TYPE (arg);
3319 arg = TREE_OPERAND (arg, 0);
3320 }
3321
3322 switch (code)
3323 {
3324 case CONVERT_EXPR:
3325 /* This is used for unary plus, because a CONVERT_EXPR
3326 is enough to prevent anybody from looking inside for
3327 associativity, but won't generate any code. */
3328 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
3329 || typecode == FIXED_POINT_TYPE || typecode == COMPLEX_TYPE
3330 || typecode == VECTOR_TYPE))
3331 {
3332 error_at (location, "wrong type argument to unary plus");
3333 return error_mark_node;
3334 }
3335 else if (!noconvert)
3336 arg = default_conversion (arg);
3337 arg = non_lvalue_loc (location, arg);
3338 break;
3339
3340 case NEGATE_EXPR:
3341 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
3342 || typecode == FIXED_POINT_TYPE || typecode == COMPLEX_TYPE
3343 || typecode == VECTOR_TYPE))
3344 {
3345 error_at (location, "wrong type argument to unary minus");
3346 return error_mark_node;
3347 }
3348 else if (!noconvert)
3349 arg = default_conversion (arg);
3350 break;
3351
3352 case BIT_NOT_EXPR:
3353 /* ~ works on integer types and non float vectors. */
3354 if (typecode == INTEGER_TYPE
3355 || (typecode == VECTOR_TYPE
3356 && !VECTOR_FLOAT_TYPE_P (TREE_TYPE (arg))))
3357 {
3358 if (!noconvert)
3359 arg = default_conversion (arg);
3360 }
3361 else if (typecode == COMPLEX_TYPE)
3362 {
3363 code = CONJ_EXPR;
3364 pedwarn (location, OPT_pedantic,
3365 "ISO C does not support %<~%> for complex conjugation");
3366 if (!noconvert)
3367 arg = default_conversion (arg);
3368 }
3369 else
3370 {
3371 error_at (location, "wrong type argument to bit-complement");
3372 return error_mark_node;
3373 }
3374 break;
3375
3376 case ABS_EXPR:
3377 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
3378 {
3379 error_at (location, "wrong type argument to abs");
3380 return error_mark_node;
3381 }
3382 else if (!noconvert)
3383 arg = default_conversion (arg);
3384 break;
3385
3386 case CONJ_EXPR:
3387 /* Conjugating a real value is a no-op, but allow it anyway. */
3388 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
3389 || typecode == COMPLEX_TYPE))
3390 {
3391 error_at (location, "wrong type argument to conjugation");
3392 return error_mark_node;
3393 }
3394 else if (!noconvert)
3395 arg = default_conversion (arg);
3396 break;
3397
3398 case TRUTH_NOT_EXPR:
3399 if (typecode != INTEGER_TYPE && typecode != FIXED_POINT_TYPE
3400 && typecode != REAL_TYPE && typecode != POINTER_TYPE
3401 && typecode != COMPLEX_TYPE)
3402 {
3403 error_at (location,
3404 "wrong type argument to unary exclamation mark");
3405 return error_mark_node;
3406 }
3407 arg = c_objc_common_truthvalue_conversion (location, arg);
3408 ret = invert_truthvalue_loc (location, arg);
3409 /* If the TRUTH_NOT_EXPR has been folded, reset the location. */
3410 if (EXPR_P (ret) && EXPR_HAS_LOCATION (ret))
3411 location = EXPR_LOCATION (ret);
3412 goto return_build_unary_op;
3413
3414 case REALPART_EXPR:
3415 if (TREE_CODE (arg) == COMPLEX_CST)
3416 ret = TREE_REALPART (arg);
3417 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3418 ret = fold_build1_loc (location,
3419 REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3420 else
3421 ret = arg;
3422 if (eptype && TREE_CODE (eptype) == COMPLEX_TYPE)
3423 eptype = TREE_TYPE (eptype);
3424 goto return_build_unary_op;
3425
3426 case IMAGPART_EXPR:
3427 if (TREE_CODE (arg) == COMPLEX_CST)
3428 ret = TREE_IMAGPART (arg);
3429 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3430 ret = fold_build1_loc (location,
3431 IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3432 else
3433 ret = omit_one_operand_loc (location, TREE_TYPE (arg),
3434 integer_zero_node, arg);
3435 if (eptype && TREE_CODE (eptype) == COMPLEX_TYPE)
3436 eptype = TREE_TYPE (eptype);
3437 goto return_build_unary_op;
3438
3439 case PREINCREMENT_EXPR:
3440 case POSTINCREMENT_EXPR:
3441 case PREDECREMENT_EXPR:
3442 case POSTDECREMENT_EXPR:
3443
3444 if (TREE_CODE (arg) == C_MAYBE_CONST_EXPR)
3445 {
3446 tree inner = build_unary_op (location, code,
3447 C_MAYBE_CONST_EXPR_EXPR (arg), flag);
3448 if (inner == error_mark_node)
3449 return error_mark_node;
3450 ret = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (inner),
3451 C_MAYBE_CONST_EXPR_PRE (arg), inner);
3452 gcc_assert (!C_MAYBE_CONST_EXPR_INT_OPERANDS (arg));
3453 C_MAYBE_CONST_EXPR_NON_CONST (ret) = 1;
3454 goto return_build_unary_op;
3455 }
3456
3457 /* Complain about anything that is not a true lvalue. */
3458 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
3459 || code == POSTINCREMENT_EXPR)
3460 ? lv_increment
3461 : lv_decrement)))
3462 return error_mark_node;
3463
3464 if (warn_cxx_compat && TREE_CODE (TREE_TYPE (arg)) == ENUMERAL_TYPE)
3465 {
3466 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3467 warning_at (location, OPT_Wc___compat,
3468 "increment of enumeration value is invalid in C++");
3469 else
3470 warning_at (location, OPT_Wc___compat,
3471 "decrement of enumeration value is invalid in C++");
3472 }
3473
3474 /* Ensure the argument is fully folded inside any SAVE_EXPR. */
3475 arg = c_fully_fold (arg, false, NULL);
3476
3477 /* Increment or decrement the real part of the value,
3478 and don't change the imaginary part. */
3479 if (typecode == COMPLEX_TYPE)
3480 {
3481 tree real, imag;
3482
3483 pedwarn (location, OPT_pedantic,
3484 "ISO C does not support %<++%> and %<--%> on complex types");
3485
3486 arg = stabilize_reference (arg);
3487 real = build_unary_op (EXPR_LOCATION (arg), REALPART_EXPR, arg, 1);
3488 imag = build_unary_op (EXPR_LOCATION (arg), IMAGPART_EXPR, arg, 1);
3489 real = build_unary_op (EXPR_LOCATION (arg), code, real, 1);
3490 if (real == error_mark_node || imag == error_mark_node)
3491 return error_mark_node;
3492 ret = build2 (COMPLEX_EXPR, TREE_TYPE (arg),
3493 real, imag);
3494 goto return_build_unary_op;
3495 }
3496
3497 /* Report invalid types. */
3498
3499 if (typecode != POINTER_TYPE && typecode != FIXED_POINT_TYPE
3500 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
3501 {
3502 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3503 error_at (location, "wrong type argument to increment");
3504 else
3505 error_at (location, "wrong type argument to decrement");
3506
3507 return error_mark_node;
3508 }
3509
3510 {
3511 tree inc;
3512
3513 argtype = TREE_TYPE (arg);
3514
3515 /* Compute the increment. */
3516
3517 if (typecode == POINTER_TYPE)
3518 {
3519 /* If pointer target is an undefined struct,
3520 we just cannot know how to do the arithmetic. */
3521 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (argtype)))
3522 {
3523 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3524 error_at (location,
3525 "increment of pointer to unknown structure");
3526 else
3527 error_at (location,
3528 "decrement of pointer to unknown structure");
3529 }
3530 else if (TREE_CODE (TREE_TYPE (argtype)) == FUNCTION_TYPE
3531 || TREE_CODE (TREE_TYPE (argtype)) == VOID_TYPE)
3532 {
3533 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3534 pedwarn (location, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
3535 "wrong type argument to increment");
3536 else
3537 pedwarn (location, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
3538 "wrong type argument to decrement");
3539 }
3540
3541 inc = c_size_in_bytes (TREE_TYPE (argtype));
3542 inc = fold_convert_loc (location, sizetype, inc);
3543 }
3544 else if (FRACT_MODE_P (TYPE_MODE (argtype)))
3545 {
3546 /* For signed fract types, we invert ++ to -- or
3547 -- to ++, and change inc from 1 to -1, because
3548 it is not possible to represent 1 in signed fract constants.
3549 For unsigned fract types, the result always overflows and
3550 we get an undefined (original) or the maximum value. */
3551 if (code == PREINCREMENT_EXPR)
3552 code = PREDECREMENT_EXPR;
3553 else if (code == PREDECREMENT_EXPR)
3554 code = PREINCREMENT_EXPR;
3555 else if (code == POSTINCREMENT_EXPR)
3556 code = POSTDECREMENT_EXPR;
3557 else /* code == POSTDECREMENT_EXPR */
3558 code = POSTINCREMENT_EXPR;
3559
3560 inc = integer_minus_one_node;
3561 inc = convert (argtype, inc);
3562 }
3563 else
3564 {
3565 inc = integer_one_node;
3566 inc = convert (argtype, inc);
3567 }
3568
3569 /* Report a read-only lvalue. */
3570 if (TYPE_READONLY (argtype))
3571 {
3572 readonly_error (arg,
3573 ((code == PREINCREMENT_EXPR
3574 || code == POSTINCREMENT_EXPR)
3575 ? lv_increment : lv_decrement));
3576 return error_mark_node;
3577 }
3578 else if (TREE_READONLY (arg))
3579 readonly_warning (arg,
3580 ((code == PREINCREMENT_EXPR
3581 || code == POSTINCREMENT_EXPR)
3582 ? lv_increment : lv_decrement));
3583
3584 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3585 val = boolean_increment (code, arg);
3586 else
3587 val = build2 (code, TREE_TYPE (arg), arg, inc);
3588 TREE_SIDE_EFFECTS (val) = 1;
3589 if (TREE_CODE (val) != code)
3590 TREE_NO_WARNING (val) = 1;
3591 ret = val;
3592 goto return_build_unary_op;
3593 }
3594
3595 case ADDR_EXPR:
3596 /* Note that this operation never does default_conversion. */
3597
3598 /* The operand of unary '&' must be an lvalue (which excludes
3599 expressions of type void), or, in C99, the result of a [] or
3600 unary '*' operator. */
3601 if (VOID_TYPE_P (TREE_TYPE (arg))
3602 && TYPE_QUALS (TREE_TYPE (arg)) == TYPE_UNQUALIFIED
3603 && (TREE_CODE (arg) != INDIRECT_REF
3604 || !flag_isoc99))
3605 pedwarn (location, 0, "taking address of expression of type %<void%>");
3606
3607 /* Let &* cancel out to simplify resulting code. */
3608 if (TREE_CODE (arg) == INDIRECT_REF)
3609 {
3610 /* Don't let this be an lvalue. */
3611 if (lvalue_p (TREE_OPERAND (arg, 0)))
3612 return non_lvalue_loc (location, TREE_OPERAND (arg, 0));
3613 ret = TREE_OPERAND (arg, 0);
3614 goto return_build_unary_op;
3615 }
3616
3617 /* For &x[y], return x+y */
3618 if (TREE_CODE (arg) == ARRAY_REF)
3619 {
3620 tree op0 = TREE_OPERAND (arg, 0);
3621 if (!c_mark_addressable (op0))
3622 return error_mark_node;
3623 return build_binary_op (location, PLUS_EXPR,
3624 (TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE
3625 ? array_to_pointer_conversion (location,
3626 op0)
3627 : op0),
3628 TREE_OPERAND (arg, 1), 1);
3629 }
3630
3631 /* Anything not already handled and not a true memory reference
3632 or a non-lvalue array is an error. */
3633 else if (typecode != FUNCTION_TYPE && !flag
3634 && !lvalue_or_else (arg, lv_addressof))
3635 return error_mark_node;
3636
3637 /* Move address operations inside C_MAYBE_CONST_EXPR to simplify
3638 folding later. */
3639 if (TREE_CODE (arg) == C_MAYBE_CONST_EXPR)
3640 {
3641 tree inner = build_unary_op (location, code,
3642 C_MAYBE_CONST_EXPR_EXPR (arg), flag);
3643 ret = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (inner),
3644 C_MAYBE_CONST_EXPR_PRE (arg), inner);
3645 gcc_assert (!C_MAYBE_CONST_EXPR_INT_OPERANDS (arg));
3646 C_MAYBE_CONST_EXPR_NON_CONST (ret)
3647 = C_MAYBE_CONST_EXPR_NON_CONST (arg);
3648 goto return_build_unary_op;
3649 }
3650
3651 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3652 argtype = TREE_TYPE (arg);
3653
3654 /* If the lvalue is const or volatile, merge that into the type
3655 to which the address will point. Note that you can't get a
3656 restricted pointer by taking the address of something, so we
3657 only have to deal with `const' and `volatile' here. */
3658 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
3659 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
3660 argtype = c_build_type_variant (argtype,
3661 TREE_READONLY (arg),
3662 TREE_THIS_VOLATILE (arg));
3663
3664 if (!c_mark_addressable (arg))
3665 return error_mark_node;
3666
3667 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
3668 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
3669
3670 argtype = build_pointer_type (argtype);
3671
3672 /* ??? Cope with user tricks that amount to offsetof. Delete this
3673 when we have proper support for integer constant expressions. */
3674 val = get_base_address (arg);
3675 if (val && TREE_CODE (val) == INDIRECT_REF
3676 && TREE_CONSTANT (TREE_OPERAND (val, 0)))
3677 {
3678 tree op0 = fold_convert_loc (location, sizetype,
3679 fold_offsetof (arg, val)), op1;
3680
3681 op1 = fold_convert_loc (location, argtype, TREE_OPERAND (val, 0));
3682 ret = fold_build2_loc (location, POINTER_PLUS_EXPR, argtype, op1, op0);
3683 goto return_build_unary_op;
3684 }
3685
3686 val = build1 (ADDR_EXPR, argtype, arg);
3687
3688 ret = val;
3689 goto return_build_unary_op;
3690
3691 default:
3692 gcc_unreachable ();
3693 }
3694
3695 if (argtype == 0)
3696 argtype = TREE_TYPE (arg);
3697 if (TREE_CODE (arg) == INTEGER_CST)
3698 ret = (require_constant_value
3699 ? fold_build1_initializer_loc (location, code, argtype, arg)
3700 : fold_build1_loc (location, code, argtype, arg));
3701 else
3702 ret = build1 (code, argtype, arg);
3703 return_build_unary_op:
3704 gcc_assert (ret != error_mark_node);
3705 if (TREE_CODE (ret) == INTEGER_CST && !TREE_OVERFLOW (ret)
3706 && !(TREE_CODE (xarg) == INTEGER_CST && !TREE_OVERFLOW (xarg)))
3707 ret = build1 (NOP_EXPR, TREE_TYPE (ret), ret);
3708 else if (TREE_CODE (ret) != INTEGER_CST && int_operands)
3709 ret = note_integer_operands (ret);
3710 if (eptype)
3711 ret = build1 (EXCESS_PRECISION_EXPR, eptype, ret);
3712 protected_set_expr_location (ret, location);
3713 return ret;
3714 }
3715
3716 /* Return nonzero if REF is an lvalue valid for this language.
3717 Lvalues can be assigned, unless their type has TYPE_READONLY.
3718 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
3719
3720 bool
3721 lvalue_p (const_tree ref)
3722 {
3723 const enum tree_code code = TREE_CODE (ref);
3724
3725 switch (code)
3726 {
3727 case REALPART_EXPR:
3728 case IMAGPART_EXPR:
3729 case COMPONENT_REF:
3730 return lvalue_p (TREE_OPERAND (ref, 0));
3731
3732 case C_MAYBE_CONST_EXPR:
3733 return lvalue_p (TREE_OPERAND (ref, 1));
3734
3735 case COMPOUND_LITERAL_EXPR:
3736 case STRING_CST:
3737 return 1;
3738
3739 case INDIRECT_REF:
3740 case ARRAY_REF:
3741 case VAR_DECL:
3742 case PARM_DECL:
3743 case RESULT_DECL:
3744 case ERROR_MARK:
3745 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3746 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3747
3748 case BIND_EXPR:
3749 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3750
3751 default:
3752 return 0;
3753 }
3754 }
3755 \f
3756 /* Give an error for storing in something that is 'const'. */
3757
3758 static void
3759 readonly_error (tree arg, enum lvalue_use use)
3760 {
3761 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement
3762 || use == lv_asm);
3763 /* Using this macro rather than (for example) arrays of messages
3764 ensures that all the format strings are checked at compile
3765 time. */
3766 #define READONLY_MSG(A, I, D, AS) (use == lv_assign ? (A) \
3767 : (use == lv_increment ? (I) \
3768 : (use == lv_decrement ? (D) : (AS))))
3769 if (TREE_CODE (arg) == COMPONENT_REF)
3770 {
3771 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3772 readonly_error (TREE_OPERAND (arg, 0), use);
3773 else
3774 error (READONLY_MSG (G_("assignment of read-only member %qD"),
3775 G_("increment of read-only member %qD"),
3776 G_("decrement of read-only member %qD"),
3777 G_("read-only member %qD used as %<asm%> output")),
3778 TREE_OPERAND (arg, 1));
3779 }
3780 else if (TREE_CODE (arg) == VAR_DECL)
3781 error (READONLY_MSG (G_("assignment of read-only variable %qD"),
3782 G_("increment of read-only variable %qD"),
3783 G_("decrement of read-only variable %qD"),
3784 G_("read-only variable %qD used as %<asm%> output")),
3785 arg);
3786 else
3787 error (READONLY_MSG (G_("assignment of read-only location %qE"),
3788 G_("increment of read-only location %qE"),
3789 G_("decrement of read-only location %qE"),
3790 G_("read-only location %qE used as %<asm%> output")),
3791 arg);
3792 }
3793
3794 /* Give a warning for storing in something that is read-only in GCC
3795 terms but not const in ISO C terms. */
3796
3797 static void
3798 readonly_warning (tree arg, enum lvalue_use use)
3799 {
3800 switch (use)
3801 {
3802 case lv_assign:
3803 warning (0, "assignment of read-only location %qE", arg);
3804 break;
3805 case lv_increment:
3806 warning (0, "increment of read-only location %qE", arg);
3807 break;
3808 case lv_decrement:
3809 warning (0, "decrement of read-only location %qE", arg);
3810 break;
3811 default:
3812 gcc_unreachable ();
3813 }
3814 return;
3815 }
3816
3817
3818 /* Return nonzero if REF is an lvalue valid for this language;
3819 otherwise, print an error message and return zero. USE says
3820 how the lvalue is being used and so selects the error message. */
3821
3822 static int
3823 lvalue_or_else (const_tree ref, enum lvalue_use use)
3824 {
3825 int win = lvalue_p (ref);
3826
3827 if (!win)
3828 lvalue_error (use);
3829
3830 return win;
3831 }
3832 \f
3833 /* Mark EXP saying that we need to be able to take the
3834 address of it; it should not be allocated in a register.
3835 Returns true if successful. */
3836
3837 bool
3838 c_mark_addressable (tree exp)
3839 {
3840 tree x = exp;
3841
3842 while (1)
3843 switch (TREE_CODE (x))
3844 {
3845 case COMPONENT_REF:
3846 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3847 {
3848 error
3849 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
3850 return false;
3851 }
3852
3853 /* ... fall through ... */
3854
3855 case ADDR_EXPR:
3856 case ARRAY_REF:
3857 case REALPART_EXPR:
3858 case IMAGPART_EXPR:
3859 x = TREE_OPERAND (x, 0);
3860 break;
3861
3862 case COMPOUND_LITERAL_EXPR:
3863 case CONSTRUCTOR:
3864 TREE_ADDRESSABLE (x) = 1;
3865 return true;
3866
3867 case VAR_DECL:
3868 case CONST_DECL:
3869 case PARM_DECL:
3870 case RESULT_DECL:
3871 if (C_DECL_REGISTER (x)
3872 && DECL_NONLOCAL (x))
3873 {
3874 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3875 {
3876 error
3877 ("global register variable %qD used in nested function", x);
3878 return false;
3879 }
3880 pedwarn (input_location, 0, "register variable %qD used in nested function", x);
3881 }
3882 else if (C_DECL_REGISTER (x))
3883 {
3884 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3885 error ("address of global register variable %qD requested", x);
3886 else
3887 error ("address of register variable %qD requested", x);
3888 return false;
3889 }
3890
3891 /* drops in */
3892 case FUNCTION_DECL:
3893 TREE_ADDRESSABLE (x) = 1;
3894 /* drops out */
3895 default:
3896 return true;
3897 }
3898 }
3899 \f
3900 /* Build and return a conditional expression IFEXP ? OP1 : OP2. If
3901 IFEXP_BCP then the condition is a call to __builtin_constant_p, and
3902 if folded to an integer constant then the unselected half may
3903 contain arbitrary operations not normally permitted in constant
3904 expressions. Set the location of the expression to LOC. */
3905
3906 tree
3907 build_conditional_expr (location_t colon_loc, tree ifexp, bool ifexp_bcp,
3908 tree op1, tree op1_original_type, tree op2,
3909 tree op2_original_type)
3910 {
3911 tree type1;
3912 tree type2;
3913 enum tree_code code1;
3914 enum tree_code code2;
3915 tree result_type = NULL;
3916 tree ep_result_type = NULL;
3917 tree orig_op1 = op1, orig_op2 = op2;
3918 bool int_const, op1_int_operands, op2_int_operands, int_operands;
3919 bool ifexp_int_operands;
3920 tree ret;
3921 bool objc_ok;
3922
3923 op1_int_operands = EXPR_INT_CONST_OPERANDS (orig_op1);
3924 if (op1_int_operands)
3925 op1 = remove_c_maybe_const_expr (op1);
3926 op2_int_operands = EXPR_INT_CONST_OPERANDS (orig_op2);
3927 if (op2_int_operands)
3928 op2 = remove_c_maybe_const_expr (op2);
3929 ifexp_int_operands = EXPR_INT_CONST_OPERANDS (ifexp);
3930 if (ifexp_int_operands)
3931 ifexp = remove_c_maybe_const_expr (ifexp);
3932
3933 /* Promote both alternatives. */
3934
3935 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3936 op1 = default_conversion (op1);
3937 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3938 op2 = default_conversion (op2);
3939
3940 if (TREE_CODE (ifexp) == ERROR_MARK
3941 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3942 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3943 return error_mark_node;
3944
3945 type1 = TREE_TYPE (op1);
3946 code1 = TREE_CODE (type1);
3947 type2 = TREE_TYPE (op2);
3948 code2 = TREE_CODE (type2);
3949
3950 /* C90 does not permit non-lvalue arrays in conditional expressions.
3951 In C99 they will be pointers by now. */
3952 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
3953 {
3954 error_at (colon_loc, "non-lvalue array in conditional expression");
3955 return error_mark_node;
3956 }
3957
3958 objc_ok = objc_compare_types (type1, type2, -3, NULL_TREE);
3959
3960 if ((TREE_CODE (op1) == EXCESS_PRECISION_EXPR
3961 || TREE_CODE (op2) == EXCESS_PRECISION_EXPR)
3962 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3963 || code1 == COMPLEX_TYPE)
3964 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3965 || code2 == COMPLEX_TYPE))
3966 {
3967 ep_result_type = c_common_type (type1, type2);
3968 if (TREE_CODE (op1) == EXCESS_PRECISION_EXPR)
3969 {
3970 op1 = TREE_OPERAND (op1, 0);
3971 type1 = TREE_TYPE (op1);
3972 gcc_assert (TREE_CODE (type1) == code1);
3973 }
3974 if (TREE_CODE (op2) == EXCESS_PRECISION_EXPR)
3975 {
3976 op2 = TREE_OPERAND (op2, 0);
3977 type2 = TREE_TYPE (op2);
3978 gcc_assert (TREE_CODE (type2) == code2);
3979 }
3980 }
3981
3982 if (warn_cxx_compat)
3983 {
3984 tree t1 = op1_original_type ? op1_original_type : TREE_TYPE (orig_op1);
3985 tree t2 = op2_original_type ? op2_original_type : TREE_TYPE (orig_op2);
3986
3987 if (TREE_CODE (t1) == ENUMERAL_TYPE
3988 && TREE_CODE (t2) == ENUMERAL_TYPE
3989 && TYPE_MAIN_VARIANT (t1) != TYPE_MAIN_VARIANT (t2))
3990 warning_at (colon_loc, OPT_Wc___compat,
3991 ("different enum types in conditional is "
3992 "invalid in C++: %qT vs %qT"),
3993 t1, t2);
3994 }
3995
3996 /* Quickly detect the usual case where op1 and op2 have the same type
3997 after promotion. */
3998 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3999 {
4000 if (type1 == type2)
4001 result_type = type1;
4002 else
4003 result_type = TYPE_MAIN_VARIANT (type1);
4004 }
4005 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
4006 || code1 == COMPLEX_TYPE)
4007 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
4008 || code2 == COMPLEX_TYPE))
4009 {
4010 result_type = c_common_type (type1, type2);
4011
4012 /* If -Wsign-compare, warn here if type1 and type2 have
4013 different signedness. We'll promote the signed to unsigned
4014 and later code won't know it used to be different.
4015 Do this check on the original types, so that explicit casts
4016 will be considered, but default promotions won't. */
4017 if (c_inhibit_evaluation_warnings == 0)
4018 {
4019 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
4020 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
4021
4022 if (unsigned_op1 ^ unsigned_op2)
4023 {
4024 bool ovf;
4025
4026 /* Do not warn if the result type is signed, since the
4027 signed type will only be chosen if it can represent
4028 all the values of the unsigned type. */
4029 if (!TYPE_UNSIGNED (result_type))
4030 /* OK */;
4031 else
4032 {
4033 bool op1_maybe_const = true;
4034 bool op2_maybe_const = true;
4035
4036 /* Do not warn if the signed quantity is an
4037 unsuffixed integer literal (or some static
4038 constant expression involving such literals) and
4039 it is non-negative. This warning requires the
4040 operands to be folded for best results, so do
4041 that folding in this case even without
4042 warn_sign_compare to avoid warning options
4043 possibly affecting code generation. */
4044 c_inhibit_evaluation_warnings
4045 += (ifexp == truthvalue_false_node);
4046 op1 = c_fully_fold (op1, require_constant_value,
4047 &op1_maybe_const);
4048 c_inhibit_evaluation_warnings
4049 -= (ifexp == truthvalue_false_node);
4050
4051 c_inhibit_evaluation_warnings
4052 += (ifexp == truthvalue_true_node);
4053 op2 = c_fully_fold (op2, require_constant_value,
4054 &op2_maybe_const);
4055 c_inhibit_evaluation_warnings
4056 -= (ifexp == truthvalue_true_node);
4057
4058 if (warn_sign_compare)
4059 {
4060 if ((unsigned_op2
4061 && tree_expr_nonnegative_warnv_p (op1, &ovf))
4062 || (unsigned_op1
4063 && tree_expr_nonnegative_warnv_p (op2, &ovf)))
4064 /* OK */;
4065 else
4066 warning_at (colon_loc, OPT_Wsign_compare,
4067 ("signed and unsigned type in "
4068 "conditional expression"));
4069 }
4070 if (!op1_maybe_const || TREE_CODE (op1) != INTEGER_CST)
4071 op1 = c_wrap_maybe_const (op1, !op1_maybe_const);
4072 if (!op2_maybe_const || TREE_CODE (op2) != INTEGER_CST)
4073 op2 = c_wrap_maybe_const (op2, !op2_maybe_const);
4074 }
4075 }
4076 }
4077 }
4078 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
4079 {
4080 if (code1 != VOID_TYPE || code2 != VOID_TYPE)
4081 pedwarn (colon_loc, OPT_pedantic,
4082 "ISO C forbids conditional expr with only one void side");
4083 result_type = void_type_node;
4084 }
4085 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
4086 {
4087 addr_space_t as1 = TYPE_ADDR_SPACE (TREE_TYPE (type1));
4088 addr_space_t as2 = TYPE_ADDR_SPACE (TREE_TYPE (type2));
4089 addr_space_t as_common;
4090
4091 if (comp_target_types (colon_loc, type1, type2))
4092 result_type = common_pointer_type (type1, type2);
4093 else if (null_pointer_constant_p (orig_op1))
4094 result_type = type2;
4095 else if (null_pointer_constant_p (orig_op2))
4096 result_type = type1;
4097 else if (!addr_space_superset (as1, as2, &as_common))
4098 {
4099 error_at (colon_loc, "pointers to disjoint address spaces "
4100 "used in conditional expression");
4101 return error_mark_node;
4102 }
4103 else if (VOID_TYPE_P (TREE_TYPE (type1)))
4104 {
4105 if (TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
4106 pedwarn (colon_loc, OPT_pedantic,
4107 "ISO C forbids conditional expr between "
4108 "%<void *%> and function pointer");
4109 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
4110 TREE_TYPE (type2)));
4111 }
4112 else if (VOID_TYPE_P (TREE_TYPE (type2)))
4113 {
4114 if (TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
4115 pedwarn (colon_loc, OPT_pedantic,
4116 "ISO C forbids conditional expr between "
4117 "%<void *%> and function pointer");
4118 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
4119 TREE_TYPE (type1)));
4120 }
4121 else
4122 {
4123 int qual = ENCODE_QUAL_ADDR_SPACE (as_common);
4124
4125 if (!objc_ok)
4126 pedwarn (colon_loc, 0,
4127 "pointer type mismatch in conditional expression");
4128 result_type = build_pointer_type
4129 (build_qualified_type (void_type_node, qual));
4130 }
4131 }
4132 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
4133 {
4134 if (!null_pointer_constant_p (orig_op2))
4135 pedwarn (colon_loc, 0,
4136 "pointer/integer type mismatch in conditional expression");
4137 else
4138 {
4139 op2 = null_pointer_node;
4140 }
4141 result_type = type1;
4142 }
4143 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
4144 {
4145 if (!null_pointer_constant_p (orig_op1))
4146 pedwarn (colon_loc, 0,
4147 "pointer/integer type mismatch in conditional expression");
4148 else
4149 {
4150 op1 = null_pointer_node;
4151 }
4152 result_type = type2;
4153 }
4154
4155 if (!result_type)
4156 {
4157 if (flag_cond_mismatch)
4158 result_type = void_type_node;
4159 else
4160 {
4161 error_at (colon_loc, "type mismatch in conditional expression");
4162 return error_mark_node;
4163 }
4164 }
4165
4166 /* Merge const and volatile flags of the incoming types. */
4167 result_type
4168 = build_type_variant (result_type,
4169 TYPE_READONLY (type1) || TYPE_READONLY (type2),
4170 TYPE_VOLATILE (type1) || TYPE_VOLATILE (type2));
4171
4172 if (result_type != type1)
4173 op1 = convert_and_check (result_type, op1);
4174 if (result_type != type2)
4175 op2 = convert_and_check (result_type, op2);
4176
4177 if (ifexp_bcp && ifexp == truthvalue_true_node)
4178 {
4179 op2_int_operands = true;
4180 op1 = c_fully_fold (op1, require_constant_value, NULL);
4181 }
4182 if (ifexp_bcp && ifexp == truthvalue_false_node)
4183 {
4184 op1_int_operands = true;
4185 op2 = c_fully_fold (op2, require_constant_value, NULL);
4186 }
4187 int_const = int_operands = (ifexp_int_operands
4188 && op1_int_operands
4189 && op2_int_operands);
4190 if (int_operands)
4191 {
4192 int_const = ((ifexp == truthvalue_true_node
4193 && TREE_CODE (orig_op1) == INTEGER_CST
4194 && !TREE_OVERFLOW (orig_op1))
4195 || (ifexp == truthvalue_false_node
4196 && TREE_CODE (orig_op2) == INTEGER_CST
4197 && !TREE_OVERFLOW (orig_op2)));
4198 }
4199 if (int_const || (ifexp_bcp && TREE_CODE (ifexp) == INTEGER_CST))
4200 ret = fold_build3_loc (colon_loc, COND_EXPR, result_type, ifexp, op1, op2);
4201 else
4202 {
4203 ret = build3 (COND_EXPR, result_type, ifexp, op1, op2);
4204 if (int_operands)
4205 ret = note_integer_operands (ret);
4206 }
4207 if (ep_result_type)
4208 ret = build1 (EXCESS_PRECISION_EXPR, ep_result_type, ret);
4209
4210 protected_set_expr_location (ret, colon_loc);
4211 return ret;
4212 }
4213 \f
4214 /* Return a compound expression that performs two expressions and
4215 returns the value of the second of them.
4216
4217 LOC is the location of the COMPOUND_EXPR. */
4218
4219 tree
4220 build_compound_expr (location_t loc, tree expr1, tree expr2)
4221 {
4222 bool expr1_int_operands, expr2_int_operands;
4223 tree eptype = NULL_TREE;
4224 tree ret;
4225
4226 expr1_int_operands = EXPR_INT_CONST_OPERANDS (expr1);
4227 if (expr1_int_operands)
4228 expr1 = remove_c_maybe_const_expr (expr1);
4229 expr2_int_operands = EXPR_INT_CONST_OPERANDS (expr2);
4230 if (expr2_int_operands)
4231 expr2 = remove_c_maybe_const_expr (expr2);
4232
4233 if (TREE_CODE (expr1) == EXCESS_PRECISION_EXPR)
4234 expr1 = TREE_OPERAND (expr1, 0);
4235 if (TREE_CODE (expr2) == EXCESS_PRECISION_EXPR)
4236 {
4237 eptype = TREE_TYPE (expr2);
4238 expr2 = TREE_OPERAND (expr2, 0);
4239 }
4240
4241 if (!TREE_SIDE_EFFECTS (expr1))
4242 {
4243 /* The left-hand operand of a comma expression is like an expression
4244 statement: with -Wunused, we should warn if it doesn't have
4245 any side-effects, unless it was explicitly cast to (void). */
4246 if (warn_unused_value)
4247 {
4248 if (VOID_TYPE_P (TREE_TYPE (expr1))
4249 && CONVERT_EXPR_P (expr1))
4250 ; /* (void) a, b */
4251 else if (VOID_TYPE_P (TREE_TYPE (expr1))
4252 && TREE_CODE (expr1) == COMPOUND_EXPR
4253 && CONVERT_EXPR_P (TREE_OPERAND (expr1, 1)))
4254 ; /* (void) a, (void) b, c */
4255 else
4256 warning_at (loc, OPT_Wunused_value,
4257 "left-hand operand of comma expression has no effect");
4258 }
4259 }
4260
4261 /* With -Wunused, we should also warn if the left-hand operand does have
4262 side-effects, but computes a value which is not used. For example, in
4263 `foo() + bar(), baz()' the result of the `+' operator is not used,
4264 so we should issue a warning. */
4265 else if (warn_unused_value)
4266 warn_if_unused_value (expr1, loc);
4267
4268 if (expr2 == error_mark_node)
4269 return error_mark_node;
4270
4271 ret = build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
4272
4273 if (flag_isoc99
4274 && expr1_int_operands
4275 && expr2_int_operands)
4276 ret = note_integer_operands (ret);
4277
4278 if (eptype)
4279 ret = build1 (EXCESS_PRECISION_EXPR, eptype, ret);
4280
4281 protected_set_expr_location (ret, loc);
4282 return ret;
4283 }
4284
4285 /* Issue -Wcast-qual warnings when appropriate. TYPE is the type to
4286 which we are casting. OTYPE is the type of the expression being
4287 cast. Both TYPE and OTYPE are pointer types. -Wcast-qual appeared
4288 on the command line. Named address space qualifiers are not handled
4289 here, because they result in different warnings. */
4290
4291 static void
4292 handle_warn_cast_qual (tree type, tree otype)
4293 {
4294 tree in_type = type;
4295 tree in_otype = otype;
4296 int added = 0;
4297 int discarded = 0;
4298 bool is_const;
4299
4300 /* Check that the qualifiers on IN_TYPE are a superset of the
4301 qualifiers of IN_OTYPE. The outermost level of POINTER_TYPE
4302 nodes is uninteresting and we stop as soon as we hit a
4303 non-POINTER_TYPE node on either type. */
4304 do
4305 {
4306 in_otype = TREE_TYPE (in_otype);
4307 in_type = TREE_TYPE (in_type);
4308
4309 /* GNU C allows cv-qualified function types. 'const' means the
4310 function is very pure, 'volatile' means it can't return. We
4311 need to warn when such qualifiers are added, not when they're
4312 taken away. */
4313 if (TREE_CODE (in_otype) == FUNCTION_TYPE
4314 && TREE_CODE (in_type) == FUNCTION_TYPE)
4315 added |= (TYPE_QUALS_NO_ADDR_SPACE (in_type)
4316 & ~TYPE_QUALS_NO_ADDR_SPACE (in_otype));
4317 else
4318 discarded |= (TYPE_QUALS_NO_ADDR_SPACE (in_otype)
4319 & ~TYPE_QUALS_NO_ADDR_SPACE (in_type));
4320 }
4321 while (TREE_CODE (in_type) == POINTER_TYPE
4322 && TREE_CODE (in_otype) == POINTER_TYPE);
4323
4324 if (added)
4325 warning (OPT_Wcast_qual, "cast adds new qualifiers to function type");
4326
4327 if (discarded)
4328 /* There are qualifiers present in IN_OTYPE that are not present
4329 in IN_TYPE. */
4330 warning (OPT_Wcast_qual,
4331 "cast discards qualifiers from pointer target type");
4332
4333 if (added || discarded)
4334 return;
4335
4336 /* A cast from **T to const **T is unsafe, because it can cause a
4337 const value to be changed with no additional warning. We only
4338 issue this warning if T is the same on both sides, and we only
4339 issue the warning if there are the same number of pointers on
4340 both sides, as otherwise the cast is clearly unsafe anyhow. A
4341 cast is unsafe when a qualifier is added at one level and const
4342 is not present at all outer levels.
4343
4344 To issue this warning, we check at each level whether the cast
4345 adds new qualifiers not already seen. We don't need to special
4346 case function types, as they won't have the same
4347 TYPE_MAIN_VARIANT. */
4348
4349 if (TYPE_MAIN_VARIANT (in_type) != TYPE_MAIN_VARIANT (in_otype))
4350 return;
4351 if (TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE)
4352 return;
4353
4354 in_type = type;
4355 in_otype = otype;
4356 is_const = TYPE_READONLY (TREE_TYPE (in_type));
4357 do
4358 {
4359 in_type = TREE_TYPE (in_type);
4360 in_otype = TREE_TYPE (in_otype);
4361 if ((TYPE_QUALS (in_type) &~ TYPE_QUALS (in_otype)) != 0
4362 && !is_const)
4363 {
4364 warning (OPT_Wcast_qual,
4365 ("new qualifiers in middle of multi-level non-const cast "
4366 "are unsafe"));
4367 break;
4368 }
4369 if (is_const)
4370 is_const = TYPE_READONLY (in_type);
4371 }
4372 while (TREE_CODE (in_type) == POINTER_TYPE);
4373 }
4374
4375 /* Build an expression representing a cast to type TYPE of expression EXPR.
4376 LOC is the location of the cast-- typically the open paren of the cast. */
4377
4378 tree
4379 build_c_cast (location_t loc, tree type, tree expr)
4380 {
4381 tree value;
4382
4383 if (TREE_CODE (expr) == EXCESS_PRECISION_EXPR)
4384 expr = TREE_OPERAND (expr, 0);
4385
4386 value = expr;
4387
4388 if (type == error_mark_node || expr == error_mark_node)
4389 return error_mark_node;
4390
4391 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
4392 only in <protocol> qualifications. But when constructing cast expressions,
4393 the protocols do matter and must be kept around. */
4394 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
4395 return build1 (NOP_EXPR, type, expr);
4396
4397 type = TYPE_MAIN_VARIANT (type);
4398
4399 if (TREE_CODE (type) == ARRAY_TYPE)
4400 {
4401 error_at (loc, "cast specifies array type");
4402 return error_mark_node;
4403 }
4404
4405 if (TREE_CODE (type) == FUNCTION_TYPE)
4406 {
4407 error_at (loc, "cast specifies function type");
4408 return error_mark_node;
4409 }
4410
4411 if (!VOID_TYPE_P (type))
4412 {
4413 value = require_complete_type (value);
4414 if (value == error_mark_node)
4415 return error_mark_node;
4416 }
4417
4418 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
4419 {
4420 if (TREE_CODE (type) == RECORD_TYPE
4421 || TREE_CODE (type) == UNION_TYPE)
4422 pedwarn (loc, OPT_pedantic,
4423 "ISO C forbids casting nonscalar to the same type");
4424 }
4425 else if (TREE_CODE (type) == UNION_TYPE)
4426 {
4427 tree field;
4428
4429 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
4430 if (TREE_TYPE (field) != error_mark_node
4431 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
4432 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
4433 break;
4434
4435 if (field)
4436 {
4437 tree t;
4438 bool maybe_const = true;
4439
4440 pedwarn (loc, OPT_pedantic, "ISO C forbids casts to union type");
4441 t = c_fully_fold (value, false, &maybe_const);
4442 t = build_constructor_single (type, field, t);
4443 if (!maybe_const)
4444 t = c_wrap_maybe_const (t, true);
4445 t = digest_init (loc, type, t,
4446 NULL_TREE, false, true, 0);
4447 TREE_CONSTANT (t) = TREE_CONSTANT (value);
4448 return t;
4449 }
4450 error_at (loc, "cast to union type from type not present in union");
4451 return error_mark_node;
4452 }
4453 else
4454 {
4455 tree otype, ovalue;
4456
4457 if (type == void_type_node)
4458 {
4459 tree t = build1 (CONVERT_EXPR, type, value);
4460 SET_EXPR_LOCATION (t, loc);
4461 return t;
4462 }
4463
4464 otype = TREE_TYPE (value);
4465
4466 /* Optionally warn about potentially worrisome casts. */
4467 if (warn_cast_qual
4468 && TREE_CODE (type) == POINTER_TYPE
4469 && TREE_CODE (otype) == POINTER_TYPE)
4470 handle_warn_cast_qual (type, otype);
4471
4472 /* Warn about conversions between pointers to disjoint
4473 address spaces. */
4474 if (TREE_CODE (type) == POINTER_TYPE
4475 && TREE_CODE (otype) == POINTER_TYPE
4476 && !null_pointer_constant_p (value))
4477 {
4478 addr_space_t as_to = TYPE_ADDR_SPACE (TREE_TYPE (type));
4479 addr_space_t as_from = TYPE_ADDR_SPACE (TREE_TYPE (otype));
4480 addr_space_t as_common;
4481
4482 if (!addr_space_superset (as_to, as_from, &as_common))
4483 {
4484 if (ADDR_SPACE_GENERIC_P (as_from))
4485 warning_at (loc, 0, "cast to %s address space pointer "
4486 "from disjoint generic address space pointer",
4487 c_addr_space_name (as_to));
4488
4489 else if (ADDR_SPACE_GENERIC_P (as_to))
4490 warning_at (loc, 0, "cast to generic address space pointer "
4491 "from disjoint %s address space pointer",
4492 c_addr_space_name (as_from));
4493
4494 else
4495 warning_at (loc, 0, "cast to %s address space pointer "
4496 "from disjoint %s address space pointer",
4497 c_addr_space_name (as_to),
4498 c_addr_space_name (as_from));
4499 }
4500 }
4501
4502 /* Warn about possible alignment problems. */
4503 if (STRICT_ALIGNMENT
4504 && TREE_CODE (type) == POINTER_TYPE
4505 && TREE_CODE (otype) == POINTER_TYPE
4506 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
4507 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
4508 /* Don't warn about opaque types, where the actual alignment
4509 restriction is unknown. */
4510 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
4511 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
4512 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
4513 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
4514 warning_at (loc, OPT_Wcast_align,
4515 "cast increases required alignment of target type");
4516
4517 if (TREE_CODE (type) == INTEGER_TYPE
4518 && TREE_CODE (otype) == POINTER_TYPE
4519 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
4520 /* Unlike conversion of integers to pointers, where the
4521 warning is disabled for converting constants because
4522 of cases such as SIG_*, warn about converting constant
4523 pointers to integers. In some cases it may cause unwanted
4524 sign extension, and a warning is appropriate. */
4525 warning_at (loc, OPT_Wpointer_to_int_cast,
4526 "cast from pointer to integer of different size");
4527
4528 if (TREE_CODE (value) == CALL_EXPR
4529 && TREE_CODE (type) != TREE_CODE (otype))
4530 warning_at (loc, OPT_Wbad_function_cast,
4531 "cast from function call of type %qT "
4532 "to non-matching type %qT", otype, type);
4533
4534 if (TREE_CODE (type) == POINTER_TYPE
4535 && TREE_CODE (otype) == INTEGER_TYPE
4536 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
4537 /* Don't warn about converting any constant. */
4538 && !TREE_CONSTANT (value))
4539 warning_at (loc,
4540 OPT_Wint_to_pointer_cast, "cast to pointer from integer "
4541 "of different size");
4542
4543 if (warn_strict_aliasing <= 2)
4544 strict_aliasing_warning (otype, type, expr);
4545
4546 /* If pedantic, warn for conversions between function and object
4547 pointer types, except for converting a null pointer constant
4548 to function pointer type. */
4549 if (pedantic
4550 && TREE_CODE (type) == POINTER_TYPE
4551 && TREE_CODE (otype) == POINTER_TYPE
4552 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
4553 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
4554 pedwarn (loc, OPT_pedantic, "ISO C forbids "
4555 "conversion of function pointer to object pointer type");
4556
4557 if (pedantic
4558 && TREE_CODE (type) == POINTER_TYPE
4559 && TREE_CODE (otype) == POINTER_TYPE
4560 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
4561 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
4562 && !null_pointer_constant_p (value))
4563 pedwarn (loc, OPT_pedantic, "ISO C forbids "
4564 "conversion of object pointer to function pointer type");
4565
4566 ovalue = value;
4567 value = convert (type, value);
4568
4569 /* Ignore any integer overflow caused by the cast. */
4570 if (TREE_CODE (value) == INTEGER_CST && !FLOAT_TYPE_P (otype))
4571 {
4572 if (CONSTANT_CLASS_P (ovalue) && TREE_OVERFLOW (ovalue))
4573 {
4574 if (!TREE_OVERFLOW (value))
4575 {
4576 /* Avoid clobbering a shared constant. */
4577 value = copy_node (value);
4578 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
4579 }
4580 }
4581 else if (TREE_OVERFLOW (value))
4582 /* Reset VALUE's overflow flags, ensuring constant sharing. */
4583 value = build_int_cst_wide (TREE_TYPE (value),
4584 TREE_INT_CST_LOW (value),
4585 TREE_INT_CST_HIGH (value));
4586 }
4587 }
4588
4589 /* Don't let a cast be an lvalue. */
4590 if (value == expr)
4591 value = non_lvalue_loc (loc, value);
4592
4593 /* Don't allow the results of casting to floating-point or complex
4594 types be confused with actual constants, or casts involving
4595 integer and pointer types other than direct integer-to-integer
4596 and integer-to-pointer be confused with integer constant
4597 expressions and null pointer constants. */
4598 if (TREE_CODE (value) == REAL_CST
4599 || TREE_CODE (value) == COMPLEX_CST
4600 || (TREE_CODE (value) == INTEGER_CST
4601 && !((TREE_CODE (expr) == INTEGER_CST
4602 && INTEGRAL_TYPE_P (TREE_TYPE (expr)))
4603 || TREE_CODE (expr) == REAL_CST
4604 || TREE_CODE (expr) == COMPLEX_CST)))
4605 value = build1 (NOP_EXPR, type, value);
4606
4607 if (CAN_HAVE_LOCATION_P (value))
4608 SET_EXPR_LOCATION (value, loc);
4609 return value;
4610 }
4611
4612 /* Interpret a cast of expression EXPR to type TYPE. LOC is the
4613 location of the open paren of the cast, or the position of the cast
4614 expr. */
4615 tree
4616 c_cast_expr (location_t loc, struct c_type_name *type_name, tree expr)
4617 {
4618 tree type;
4619 tree type_expr = NULL_TREE;
4620 bool type_expr_const = true;
4621 tree ret;
4622 int saved_wsp = warn_strict_prototypes;
4623
4624 /* This avoids warnings about unprototyped casts on
4625 integers. E.g. "#define SIG_DFL (void(*)())0". */
4626 if (TREE_CODE (expr) == INTEGER_CST)
4627 warn_strict_prototypes = 0;
4628 type = groktypename (type_name, &type_expr, &type_expr_const);
4629 warn_strict_prototypes = saved_wsp;
4630
4631 ret = build_c_cast (loc, type, expr);
4632 if (type_expr)
4633 {
4634 ret = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (ret), type_expr, ret);
4635 C_MAYBE_CONST_EXPR_NON_CONST (ret) = !type_expr_const;
4636 SET_EXPR_LOCATION (ret, loc);
4637 }
4638
4639 if (CAN_HAVE_LOCATION_P (ret) && !EXPR_HAS_LOCATION (ret))
4640 SET_EXPR_LOCATION (ret, loc);
4641
4642 /* C++ does not permits types to be defined in a cast. */
4643 if (warn_cxx_compat && type_name->specs->tag_defined_p)
4644 warning_at (loc, OPT_Wc___compat,
4645 "defining a type in a cast is invalid in C++");
4646
4647 return ret;
4648 }
4649 \f
4650 /* Build an assignment expression of lvalue LHS from value RHS.
4651 If LHS_ORIGTYPE is not NULL, it is the original type of LHS, which
4652 may differ from TREE_TYPE (LHS) for an enum bitfield.
4653 MODIFYCODE is the code for a binary operator that we use
4654 to combine the old value of LHS with RHS to get the new value.
4655 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
4656 If RHS_ORIGTYPE is not NULL_TREE, it is the original type of RHS,
4657 which may differ from TREE_TYPE (RHS) for an enum value.
4658
4659 LOCATION is the location of the MODIFYCODE operator.
4660 RHS_LOC is the location of the RHS. */
4661
4662 tree
4663 build_modify_expr (location_t location, tree lhs, tree lhs_origtype,
4664 enum tree_code modifycode,
4665 location_t rhs_loc, tree rhs, tree rhs_origtype)
4666 {
4667 tree result;
4668 tree newrhs;
4669 tree rhs_semantic_type = NULL_TREE;
4670 tree lhstype = TREE_TYPE (lhs);
4671 tree olhstype = lhstype;
4672 bool npc;
4673
4674 /* Types that aren't fully specified cannot be used in assignments. */
4675 lhs = require_complete_type (lhs);
4676
4677 /* Avoid duplicate error messages from operands that had errors. */
4678 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
4679 return error_mark_node;
4680
4681 if (!lvalue_or_else (lhs, lv_assign))
4682 return error_mark_node;
4683
4684 if (TREE_CODE (rhs) == EXCESS_PRECISION_EXPR)
4685 {
4686 rhs_semantic_type = TREE_TYPE (rhs);
4687 rhs = TREE_OPERAND (rhs, 0);
4688 }
4689
4690 newrhs = rhs;
4691
4692 if (TREE_CODE (lhs) == C_MAYBE_CONST_EXPR)
4693 {
4694 tree inner = build_modify_expr (location, C_MAYBE_CONST_EXPR_EXPR (lhs),
4695 lhs_origtype, modifycode, rhs_loc, rhs,
4696 rhs_origtype);
4697 if (inner == error_mark_node)
4698 return error_mark_node;
4699 result = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (inner),
4700 C_MAYBE_CONST_EXPR_PRE (lhs), inner);
4701 gcc_assert (!C_MAYBE_CONST_EXPR_INT_OPERANDS (lhs));
4702 C_MAYBE_CONST_EXPR_NON_CONST (result) = 1;
4703 protected_set_expr_location (result, location);
4704 return result;
4705 }
4706
4707 /* If a binary op has been requested, combine the old LHS value with the RHS
4708 producing the value we should actually store into the LHS. */
4709
4710 if (modifycode != NOP_EXPR)
4711 {
4712 lhs = c_fully_fold (lhs, false, NULL);
4713 lhs = stabilize_reference (lhs);
4714 newrhs = build_binary_op (location,
4715 modifycode, lhs, rhs, 1);
4716
4717 /* The original type of the right hand side is no longer
4718 meaningful. */
4719 rhs_origtype = NULL_TREE;
4720 }
4721
4722 /* Give an error for storing in something that is 'const'. */
4723
4724 if (TYPE_READONLY (lhstype)
4725 || ((TREE_CODE (lhstype) == RECORD_TYPE
4726 || TREE_CODE (lhstype) == UNION_TYPE)
4727 && C_TYPE_FIELDS_READONLY (lhstype)))
4728 {
4729 readonly_error (lhs, lv_assign);
4730 return error_mark_node;
4731 }
4732 else if (TREE_READONLY (lhs))
4733 readonly_warning (lhs, lv_assign);
4734
4735 /* If storing into a structure or union member,
4736 it has probably been given type `int'.
4737 Compute the type that would go with
4738 the actual amount of storage the member occupies. */
4739
4740 if (TREE_CODE (lhs) == COMPONENT_REF
4741 && (TREE_CODE (lhstype) == INTEGER_TYPE
4742 || TREE_CODE (lhstype) == BOOLEAN_TYPE
4743 || TREE_CODE (lhstype) == REAL_TYPE
4744 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
4745 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
4746
4747 /* If storing in a field that is in actuality a short or narrower than one,
4748 we must store in the field in its actual type. */
4749
4750 if (lhstype != TREE_TYPE (lhs))
4751 {
4752 lhs = copy_node (lhs);
4753 TREE_TYPE (lhs) = lhstype;
4754 }
4755
4756 /* Issue -Wc++-compat warnings about an assignment to an enum type
4757 when LHS does not have its original type. This happens for,
4758 e.g., an enum bitfield in a struct. */
4759 if (warn_cxx_compat
4760 && lhs_origtype != NULL_TREE
4761 && lhs_origtype != lhstype
4762 && TREE_CODE (lhs_origtype) == ENUMERAL_TYPE)
4763 {
4764 tree checktype = (rhs_origtype != NULL_TREE
4765 ? rhs_origtype
4766 : TREE_TYPE (rhs));
4767 if (checktype != error_mark_node
4768 && TYPE_MAIN_VARIANT (checktype) != TYPE_MAIN_VARIANT (lhs_origtype))
4769 warning_at (location, OPT_Wc___compat,
4770 "enum conversion in assignment is invalid in C++");
4771 }
4772
4773 /* Convert new value to destination type. Fold it first, then
4774 restore any excess precision information, for the sake of
4775 conversion warnings. */
4776
4777 npc = null_pointer_constant_p (newrhs);
4778 newrhs = c_fully_fold (newrhs, false, NULL);
4779 if (rhs_semantic_type)
4780 newrhs = build1 (EXCESS_PRECISION_EXPR, rhs_semantic_type, newrhs);
4781 newrhs = convert_for_assignment (location, lhstype, newrhs, rhs_origtype,
4782 ic_assign, npc, NULL_TREE, NULL_TREE, 0);
4783 if (TREE_CODE (newrhs) == ERROR_MARK)
4784 return error_mark_node;
4785
4786 /* Emit ObjC write barrier, if necessary. */
4787 if (c_dialect_objc () && flag_objc_gc)
4788 {
4789 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
4790 if (result)
4791 {
4792 protected_set_expr_location (result, location);
4793 return result;
4794 }
4795 }
4796
4797 /* Scan operands. */
4798
4799 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
4800 TREE_SIDE_EFFECTS (result) = 1;
4801 protected_set_expr_location (result, location);
4802
4803 /* If we got the LHS in a different type for storing in,
4804 convert the result back to the nominal type of LHS
4805 so that the value we return always has the same type
4806 as the LHS argument. */
4807
4808 if (olhstype == TREE_TYPE (result))
4809 return result;
4810
4811 result = convert_for_assignment (location, olhstype, result, rhs_origtype,
4812 ic_assign, false, NULL_TREE, NULL_TREE, 0);
4813 protected_set_expr_location (result, location);
4814 return result;
4815 }
4816 \f
4817 /* Convert value RHS to type TYPE as preparation for an assignment to
4818 an lvalue of type TYPE. If ORIGTYPE is not NULL_TREE, it is the
4819 original type of RHS; this differs from TREE_TYPE (RHS) for enum
4820 types. NULL_POINTER_CONSTANT says whether RHS was a null pointer
4821 constant before any folding.
4822 The real work of conversion is done by `convert'.
4823 The purpose of this function is to generate error messages
4824 for assignments that are not allowed in C.
4825 ERRTYPE says whether it is argument passing, assignment,
4826 initialization or return.
4827
4828 LOCATION is the location of the RHS.
4829 FUNCTION is a tree for the function being called.
4830 PARMNUM is the number of the argument, for printing in error messages. */
4831
4832 static tree
4833 convert_for_assignment (location_t location, tree type, tree rhs,
4834 tree origtype, enum impl_conv errtype,
4835 bool null_pointer_constant, tree fundecl,
4836 tree function, int parmnum)
4837 {
4838 enum tree_code codel = TREE_CODE (type);
4839 tree orig_rhs = rhs;
4840 tree rhstype;
4841 enum tree_code coder;
4842 tree rname = NULL_TREE;
4843 bool objc_ok = false;
4844
4845 if (errtype == ic_argpass)
4846 {
4847 tree selector;
4848 /* Change pointer to function to the function itself for
4849 diagnostics. */
4850 if (TREE_CODE (function) == ADDR_EXPR
4851 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
4852 function = TREE_OPERAND (function, 0);
4853
4854 /* Handle an ObjC selector specially for diagnostics. */
4855 selector = objc_message_selector ();
4856 rname = function;
4857 if (selector && parmnum > 2)
4858 {
4859 rname = selector;
4860 parmnum -= 2;
4861 }
4862 }
4863
4864 /* This macro is used to emit diagnostics to ensure that all format
4865 strings are complete sentences, visible to gettext and checked at
4866 compile time. */
4867 #define WARN_FOR_ASSIGNMENT(LOCATION, OPT, AR, AS, IN, RE) \
4868 do { \
4869 switch (errtype) \
4870 { \
4871 case ic_argpass: \
4872 if (pedwarn (LOCATION, OPT, AR, parmnum, rname)) \
4873 inform ((fundecl && !DECL_IS_BUILTIN (fundecl)) \
4874 ? DECL_SOURCE_LOCATION (fundecl) : LOCATION, \
4875 "expected %qT but argument is of type %qT", \
4876 type, rhstype); \
4877 break; \
4878 case ic_assign: \
4879 pedwarn (LOCATION, OPT, AS); \
4880 break; \
4881 case ic_init: \
4882 pedwarn (LOCATION, OPT, IN); \
4883 break; \
4884 case ic_return: \
4885 pedwarn (LOCATION, OPT, RE); \
4886 break; \
4887 default: \
4888 gcc_unreachable (); \
4889 } \
4890 } while (0)
4891
4892 if (TREE_CODE (rhs) == EXCESS_PRECISION_EXPR)
4893 rhs = TREE_OPERAND (rhs, 0);
4894
4895 rhstype = TREE_TYPE (rhs);
4896 coder = TREE_CODE (rhstype);
4897
4898 if (coder == ERROR_MARK)
4899 return error_mark_node;
4900
4901 if (c_dialect_objc ())
4902 {
4903 int parmno;
4904
4905 switch (errtype)
4906 {
4907 case ic_return:
4908 parmno = 0;
4909 break;
4910
4911 case ic_assign:
4912 parmno = -1;
4913 break;
4914
4915 case ic_init:
4916 parmno = -2;
4917 break;
4918
4919 default:
4920 parmno = parmnum;
4921 break;
4922 }
4923
4924 objc_ok = objc_compare_types (type, rhstype, parmno, rname);
4925 }
4926
4927 if (warn_cxx_compat)
4928 {
4929 tree checktype = origtype != NULL_TREE ? origtype : rhstype;
4930 if (checktype != error_mark_node
4931 && TREE_CODE (type) == ENUMERAL_TYPE
4932 && TYPE_MAIN_VARIANT (checktype) != TYPE_MAIN_VARIANT (type))
4933 {
4934 WARN_FOR_ASSIGNMENT (input_location, OPT_Wc___compat,
4935 G_("enum conversion when passing argument "
4936 "%d of %qE is invalid in C++"),
4937 G_("enum conversion in assignment is "
4938 "invalid in C++"),
4939 G_("enum conversion in initialization is "
4940 "invalid in C++"),
4941 G_("enum conversion in return is "
4942 "invalid in C++"));
4943 }
4944 }
4945
4946 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
4947 return rhs;
4948
4949 if (coder == VOID_TYPE)
4950 {
4951 /* Except for passing an argument to an unprototyped function,
4952 this is a constraint violation. When passing an argument to
4953 an unprototyped function, it is compile-time undefined;
4954 making it a constraint in that case was rejected in
4955 DR#252. */
4956 error_at (location, "void value not ignored as it ought to be");
4957 return error_mark_node;
4958 }
4959 rhs = require_complete_type (rhs);
4960 if (rhs == error_mark_node)
4961 return error_mark_node;
4962 /* A type converts to a reference to it.
4963 This code doesn't fully support references, it's just for the
4964 special case of va_start and va_copy. */
4965 if (codel == REFERENCE_TYPE
4966 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
4967 {
4968 if (!lvalue_p (rhs))
4969 {
4970 error_at (location, "cannot pass rvalue to reference parameter");
4971 return error_mark_node;
4972 }
4973 if (!c_mark_addressable (rhs))
4974 return error_mark_node;
4975 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
4976 SET_EXPR_LOCATION (rhs, location);
4977
4978 /* We already know that these two types are compatible, but they
4979 may not be exactly identical. In fact, `TREE_TYPE (type)' is
4980 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
4981 likely to be va_list, a typedef to __builtin_va_list, which
4982 is different enough that it will cause problems later. */
4983 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
4984 {
4985 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
4986 SET_EXPR_LOCATION (rhs, location);
4987 }
4988
4989 rhs = build1 (NOP_EXPR, type, rhs);
4990 SET_EXPR_LOCATION (rhs, location);
4991 return rhs;
4992 }
4993 /* Some types can interconvert without explicit casts. */
4994 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
4995 && vector_types_convertible_p (type, TREE_TYPE (rhs), true))
4996 return convert (type, rhs);
4997 /* Arithmetic types all interconvert, and enum is treated like int. */
4998 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
4999 || codel == FIXED_POINT_TYPE
5000 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
5001 || codel == BOOLEAN_TYPE)
5002 && (coder == INTEGER_TYPE || coder == REAL_TYPE
5003 || coder == FIXED_POINT_TYPE
5004 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
5005 || coder == BOOLEAN_TYPE))
5006 {
5007 tree ret;
5008 bool save = in_late_binary_op;
5009 if (codel == BOOLEAN_TYPE)
5010 in_late_binary_op = true;
5011 ret = convert_and_check (type, orig_rhs);
5012 if (codel == BOOLEAN_TYPE)
5013 in_late_binary_op = save;
5014 return ret;
5015 }
5016
5017 /* Aggregates in different TUs might need conversion. */
5018 if ((codel == RECORD_TYPE || codel == UNION_TYPE)
5019 && codel == coder
5020 && comptypes (type, rhstype))
5021 return convert_and_check (type, rhs);
5022
5023 /* Conversion to a transparent union or record from its member types.
5024 This applies only to function arguments. */
5025 if (((codel == UNION_TYPE || codel == RECORD_TYPE)
5026 && TYPE_TRANSPARENT_AGGR (type))
5027 && errtype == ic_argpass)
5028 {
5029 tree memb, marginal_memb = NULL_TREE;
5030
5031 for (memb = TYPE_FIELDS (type); memb ; memb = TREE_CHAIN (memb))
5032 {
5033 tree memb_type = TREE_TYPE (memb);
5034
5035 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
5036 TYPE_MAIN_VARIANT (rhstype)))
5037 break;
5038
5039 if (TREE_CODE (memb_type) != POINTER_TYPE)
5040 continue;
5041
5042 if (coder == POINTER_TYPE)
5043 {
5044 tree ttl = TREE_TYPE (memb_type);
5045 tree ttr = TREE_TYPE (rhstype);
5046
5047 /* Any non-function converts to a [const][volatile] void *
5048 and vice versa; otherwise, targets must be the same.
5049 Meanwhile, the lhs target must have all the qualifiers of
5050 the rhs. */
5051 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
5052 || comp_target_types (location, memb_type, rhstype))
5053 {
5054 /* If this type won't generate any warnings, use it. */
5055 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
5056 || ((TREE_CODE (ttr) == FUNCTION_TYPE
5057 && TREE_CODE (ttl) == FUNCTION_TYPE)
5058 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
5059 == TYPE_QUALS (ttr))
5060 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
5061 == TYPE_QUALS (ttl))))
5062 break;
5063
5064 /* Keep looking for a better type, but remember this one. */
5065 if (!marginal_memb)
5066 marginal_memb = memb;
5067 }
5068 }
5069
5070 /* Can convert integer zero to any pointer type. */
5071 if (null_pointer_constant)
5072 {
5073 rhs = null_pointer_node;
5074 break;
5075 }
5076 }
5077
5078 if (memb || marginal_memb)
5079 {
5080 if (!memb)
5081 {
5082 /* We have only a marginally acceptable member type;
5083 it needs a warning. */
5084 tree ttl = TREE_TYPE (TREE_TYPE (marginal_memb));
5085 tree ttr = TREE_TYPE (rhstype);
5086
5087 /* Const and volatile mean something different for function
5088 types, so the usual warnings are not appropriate. */
5089 if (TREE_CODE (ttr) == FUNCTION_TYPE
5090 && TREE_CODE (ttl) == FUNCTION_TYPE)
5091 {
5092 /* Because const and volatile on functions are
5093 restrictions that say the function will not do
5094 certain things, it is okay to use a const or volatile
5095 function where an ordinary one is wanted, but not
5096 vice-versa. */
5097 if (TYPE_QUALS_NO_ADDR_SPACE (ttl)
5098 & ~TYPE_QUALS_NO_ADDR_SPACE (ttr))
5099 WARN_FOR_ASSIGNMENT (location, 0,
5100 G_("passing argument %d of %qE "
5101 "makes qualified function "
5102 "pointer from unqualified"),
5103 G_("assignment makes qualified "
5104 "function pointer from "
5105 "unqualified"),
5106 G_("initialization makes qualified "
5107 "function pointer from "
5108 "unqualified"),
5109 G_("return makes qualified function "
5110 "pointer from unqualified"));
5111 }
5112 else if (TYPE_QUALS_NO_ADDR_SPACE (ttr)
5113 & ~TYPE_QUALS_NO_ADDR_SPACE (ttl))
5114 WARN_FOR_ASSIGNMENT (location, 0,
5115 G_("passing argument %d of %qE discards "
5116 "qualifiers from pointer target type"),
5117 G_("assignment discards qualifiers "
5118 "from pointer target type"),
5119 G_("initialization discards qualifiers "
5120 "from pointer target type"),
5121 G_("return discards qualifiers from "
5122 "pointer target type"));
5123
5124 memb = marginal_memb;
5125 }
5126
5127 if (!fundecl || !DECL_IN_SYSTEM_HEADER (fundecl))
5128 pedwarn (location, OPT_pedantic,
5129 "ISO C prohibits argument conversion to union type");
5130
5131 rhs = fold_convert_loc (location, TREE_TYPE (memb), rhs);
5132 return build_constructor_single (type, memb, rhs);
5133 }
5134 }
5135
5136 /* Conversions among pointers */
5137 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5138 && (coder == codel))
5139 {
5140 tree ttl = TREE_TYPE (type);
5141 tree ttr = TREE_TYPE (rhstype);
5142 tree mvl = ttl;
5143 tree mvr = ttr;
5144 bool is_opaque_pointer;
5145 int target_cmp = 0; /* Cache comp_target_types () result. */
5146 addr_space_t asl;
5147 addr_space_t asr;
5148
5149 if (TREE_CODE (mvl) != ARRAY_TYPE)
5150 mvl = TYPE_MAIN_VARIANT (mvl);
5151 if (TREE_CODE (mvr) != ARRAY_TYPE)
5152 mvr = TYPE_MAIN_VARIANT (mvr);
5153 /* Opaque pointers are treated like void pointers. */
5154 is_opaque_pointer = vector_targets_convertible_p (ttl, ttr);
5155
5156 /* C++ does not allow the implicit conversion void* -> T*. However,
5157 for the purpose of reducing the number of false positives, we
5158 tolerate the special case of
5159
5160 int *p = NULL;
5161
5162 where NULL is typically defined in C to be '(void *) 0'. */
5163 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl))
5164 warning_at (location, OPT_Wc___compat,
5165 "request for implicit conversion "
5166 "from %qT to %qT not permitted in C++", rhstype, type);
5167
5168 /* See if the pointers point to incompatible address spaces. */
5169 asl = TYPE_ADDR_SPACE (ttl);
5170 asr = TYPE_ADDR_SPACE (ttr);
5171 if (!null_pointer_constant_p (rhs)
5172 && asr != asl && !targetm.addr_space.subset_p (asr, asl))
5173 {
5174 switch (errtype)
5175 {
5176 case ic_argpass:
5177 error_at (location, "passing argument %d of %qE from pointer to "
5178 "non-enclosed address space", parmnum, rname);
5179 break;
5180 case ic_assign:
5181 error_at (location, "assignment from pointer to "
5182 "non-enclosed address space");
5183 break;
5184 case ic_init:
5185 error_at (location, "initialization from pointer to "
5186 "non-enclosed address space");
5187 break;
5188 case ic_return:
5189 error_at (location, "return from pointer to "
5190 "non-enclosed address space");
5191 break;
5192 default:
5193 gcc_unreachable ();
5194 }
5195 return error_mark_node;
5196 }
5197
5198 /* Check if the right-hand side has a format attribute but the
5199 left-hand side doesn't. */
5200 if (warn_missing_format_attribute
5201 && check_missing_format_attribute (type, rhstype))
5202 {
5203 switch (errtype)
5204 {
5205 case ic_argpass:
5206 warning_at (location, OPT_Wmissing_format_attribute,
5207 "argument %d of %qE might be "
5208 "a candidate for a format attribute",
5209 parmnum, rname);
5210 break;
5211 case ic_assign:
5212 warning_at (location, OPT_Wmissing_format_attribute,
5213 "assignment left-hand side might be "
5214 "a candidate for a format attribute");
5215 break;
5216 case ic_init:
5217 warning_at (location, OPT_Wmissing_format_attribute,
5218 "initialization left-hand side might be "
5219 "a candidate for a format attribute");
5220 break;
5221 case ic_return:
5222 warning_at (location, OPT_Wmissing_format_attribute,
5223 "return type might be "
5224 "a candidate for a format attribute");
5225 break;
5226 default:
5227 gcc_unreachable ();
5228 }
5229 }
5230
5231 /* Any non-function converts to a [const][volatile] void *
5232 and vice versa; otherwise, targets must be the same.
5233 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
5234 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
5235 || (target_cmp = comp_target_types (location, type, rhstype))
5236 || is_opaque_pointer
5237 || (c_common_unsigned_type (mvl)
5238 == c_common_unsigned_type (mvr)))
5239 {
5240 if (pedantic
5241 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
5242 ||
5243 (VOID_TYPE_P (ttr)
5244 && !null_pointer_constant
5245 && TREE_CODE (ttl) == FUNCTION_TYPE)))
5246 WARN_FOR_ASSIGNMENT (location, OPT_pedantic,
5247 G_("ISO C forbids passing argument %d of "
5248 "%qE between function pointer "
5249 "and %<void *%>"),
5250 G_("ISO C forbids assignment between "
5251 "function pointer and %<void *%>"),
5252 G_("ISO C forbids initialization between "
5253 "function pointer and %<void *%>"),
5254 G_("ISO C forbids return between function "
5255 "pointer and %<void *%>"));
5256 /* Const and volatile mean something different for function types,
5257 so the usual warnings are not appropriate. */
5258 else if (TREE_CODE (ttr) != FUNCTION_TYPE
5259 && TREE_CODE (ttl) != FUNCTION_TYPE)
5260 {
5261 if (TYPE_QUALS_NO_ADDR_SPACE (ttr)
5262 & ~TYPE_QUALS_NO_ADDR_SPACE (ttl))
5263 {
5264 /* Types differing only by the presence of the 'volatile'
5265 qualifier are acceptable if the 'volatile' has been added
5266 in by the Objective-C EH machinery. */
5267 if (!objc_type_quals_match (ttl, ttr))
5268 WARN_FOR_ASSIGNMENT (location, 0,
5269 G_("passing argument %d of %qE discards "
5270 "qualifiers from pointer target type"),
5271 G_("assignment discards qualifiers "
5272 "from pointer target type"),
5273 G_("initialization discards qualifiers "
5274 "from pointer target type"),
5275 G_("return discards qualifiers from "
5276 "pointer target type"));
5277 }
5278 /* If this is not a case of ignoring a mismatch in signedness,
5279 no warning. */
5280 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
5281 || target_cmp)
5282 ;
5283 /* If there is a mismatch, do warn. */
5284 else if (warn_pointer_sign)
5285 WARN_FOR_ASSIGNMENT (location, OPT_Wpointer_sign,
5286 G_("pointer targets in passing argument "
5287 "%d of %qE differ in signedness"),
5288 G_("pointer targets in assignment "
5289 "differ in signedness"),
5290 G_("pointer targets in initialization "
5291 "differ in signedness"),
5292 G_("pointer targets in return differ "
5293 "in signedness"));
5294 }
5295 else if (TREE_CODE (ttl) == FUNCTION_TYPE
5296 && TREE_CODE (ttr) == FUNCTION_TYPE)
5297 {
5298 /* Because const and volatile on functions are restrictions
5299 that say the function will not do certain things,
5300 it is okay to use a const or volatile function
5301 where an ordinary one is wanted, but not vice-versa. */
5302 if (TYPE_QUALS_NO_ADDR_SPACE (ttl)
5303 & ~TYPE_QUALS_NO_ADDR_SPACE (ttr))
5304 WARN_FOR_ASSIGNMENT (location, 0,
5305 G_("passing argument %d of %qE makes "
5306 "qualified function pointer "
5307 "from unqualified"),
5308 G_("assignment makes qualified function "
5309 "pointer from unqualified"),
5310 G_("initialization makes qualified "
5311 "function pointer from unqualified"),
5312 G_("return makes qualified function "
5313 "pointer from unqualified"));
5314 }
5315 }
5316 else
5317 /* Avoid warning about the volatile ObjC EH puts on decls. */
5318 if (!objc_ok)
5319 WARN_FOR_ASSIGNMENT (location, 0,
5320 G_("passing argument %d of %qE from "
5321 "incompatible pointer type"),
5322 G_("assignment from incompatible pointer type"),
5323 G_("initialization from incompatible "
5324 "pointer type"),
5325 G_("return from incompatible pointer type"));
5326
5327 return convert (type, rhs);
5328 }
5329 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
5330 {
5331 /* ??? This should not be an error when inlining calls to
5332 unprototyped functions. */
5333 error_at (location, "invalid use of non-lvalue array");
5334 return error_mark_node;
5335 }
5336 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
5337 {
5338 /* An explicit constant 0 can convert to a pointer,
5339 or one that results from arithmetic, even including
5340 a cast to integer type. */
5341 if (!null_pointer_constant)
5342 WARN_FOR_ASSIGNMENT (location, 0,
5343 G_("passing argument %d of %qE makes "
5344 "pointer from integer without a cast"),
5345 G_("assignment makes pointer from integer "
5346 "without a cast"),
5347 G_("initialization makes pointer from "
5348 "integer without a cast"),
5349 G_("return makes pointer from integer "
5350 "without a cast"));
5351
5352 return convert (type, rhs);
5353 }
5354 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
5355 {
5356 WARN_FOR_ASSIGNMENT (location, 0,
5357 G_("passing argument %d of %qE makes integer "
5358 "from pointer without a cast"),
5359 G_("assignment makes integer from pointer "
5360 "without a cast"),
5361 G_("initialization makes integer from pointer "
5362 "without a cast"),
5363 G_("return makes integer from pointer "
5364 "without a cast"));
5365 return convert (type, rhs);
5366 }
5367 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
5368 {
5369 tree ret;
5370 bool save = in_late_binary_op;
5371 in_late_binary_op = true;
5372 ret = convert (type, rhs);
5373 in_late_binary_op = save;
5374 return ret;
5375 }
5376
5377 switch (errtype)
5378 {
5379 case ic_argpass:
5380 error_at (location, "incompatible type for argument %d of %qE", parmnum, rname);
5381 inform ((fundecl && !DECL_IS_BUILTIN (fundecl))
5382 ? DECL_SOURCE_LOCATION (fundecl) : input_location,
5383 "expected %qT but argument is of type %qT", type, rhstype);
5384 break;
5385 case ic_assign:
5386 error_at (location, "incompatible types when assigning to type %qT from "
5387 "type %qT", type, rhstype);
5388 break;
5389 case ic_init:
5390 error_at (location,
5391 "incompatible types when initializing type %qT using type %qT",
5392 type, rhstype);
5393 break;
5394 case ic_return:
5395 error_at (location,
5396 "incompatible types when returning type %qT but %qT was "
5397 "expected", rhstype, type);
5398 break;
5399 default:
5400 gcc_unreachable ();
5401 }
5402
5403 return error_mark_node;
5404 }
5405 \f
5406 /* If VALUE is a compound expr all of whose expressions are constant, then
5407 return its value. Otherwise, return error_mark_node.
5408
5409 This is for handling COMPOUND_EXPRs as initializer elements
5410 which is allowed with a warning when -pedantic is specified. */
5411
5412 static tree
5413 valid_compound_expr_initializer (tree value, tree endtype)
5414 {
5415 if (TREE_CODE (value) == COMPOUND_EXPR)
5416 {
5417 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
5418 == error_mark_node)
5419 return error_mark_node;
5420 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
5421 endtype);
5422 }
5423 else if (!initializer_constant_valid_p (value, endtype))
5424 return error_mark_node;
5425 else
5426 return value;
5427 }
5428 \f
5429 /* Perform appropriate conversions on the initial value of a variable,
5430 store it in the declaration DECL,
5431 and print any error messages that are appropriate.
5432 If ORIGTYPE is not NULL_TREE, it is the original type of INIT.
5433 If the init is invalid, store an ERROR_MARK.
5434
5435 INIT_LOC is the location of the initial value. */
5436
5437 void
5438 store_init_value (location_t init_loc, tree decl, tree init, tree origtype)
5439 {
5440 tree value, type;
5441 bool npc = false;
5442
5443 /* If variable's type was invalidly declared, just ignore it. */
5444
5445 type = TREE_TYPE (decl);
5446 if (TREE_CODE (type) == ERROR_MARK)
5447 return;
5448
5449 /* Digest the specified initializer into an expression. */
5450
5451 if (init)
5452 npc = null_pointer_constant_p (init);
5453 value = digest_init (init_loc, type, init, origtype, npc,
5454 true, TREE_STATIC (decl));
5455
5456 /* Store the expression if valid; else report error. */
5457
5458 if (!in_system_header
5459 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
5460 warning (OPT_Wtraditional, "traditional C rejects automatic "
5461 "aggregate initialization");
5462
5463 DECL_INITIAL (decl) = value;
5464
5465 /* ANSI wants warnings about out-of-range constant initializers. */
5466 STRIP_TYPE_NOPS (value);
5467 if (TREE_STATIC (decl))
5468 constant_expression_warning (value);
5469
5470 /* Check if we need to set array size from compound literal size. */
5471 if (TREE_CODE (type) == ARRAY_TYPE
5472 && TYPE_DOMAIN (type) == 0
5473 && value != error_mark_node)
5474 {
5475 tree inside_init = init;
5476
5477 STRIP_TYPE_NOPS (inside_init);
5478 inside_init = fold (inside_init);
5479
5480 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
5481 {
5482 tree cldecl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
5483
5484 if (TYPE_DOMAIN (TREE_TYPE (cldecl)))
5485 {
5486 /* For int foo[] = (int [3]){1}; we need to set array size
5487 now since later on array initializer will be just the
5488 brace enclosed list of the compound literal. */
5489 type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
5490 TREE_TYPE (decl) = type;
5491 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (cldecl));
5492 layout_type (type);
5493 layout_decl (cldecl, 0);
5494 }
5495 }
5496 }
5497 }
5498 \f
5499 /* Methods for storing and printing names for error messages. */
5500
5501 /* Implement a spelling stack that allows components of a name to be pushed
5502 and popped. Each element on the stack is this structure. */
5503
5504 struct spelling
5505 {
5506 int kind;
5507 union
5508 {
5509 unsigned HOST_WIDE_INT i;
5510 const char *s;
5511 } u;
5512 };
5513
5514 #define SPELLING_STRING 1
5515 #define SPELLING_MEMBER 2
5516 #define SPELLING_BOUNDS 3
5517
5518 static struct spelling *spelling; /* Next stack element (unused). */
5519 static struct spelling *spelling_base; /* Spelling stack base. */
5520 static int spelling_size; /* Size of the spelling stack. */
5521
5522 /* Macros to save and restore the spelling stack around push_... functions.
5523 Alternative to SAVE_SPELLING_STACK. */
5524
5525 #define SPELLING_DEPTH() (spelling - spelling_base)
5526 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
5527
5528 /* Push an element on the spelling stack with type KIND and assign VALUE
5529 to MEMBER. */
5530
5531 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
5532 { \
5533 int depth = SPELLING_DEPTH (); \
5534 \
5535 if (depth >= spelling_size) \
5536 { \
5537 spelling_size += 10; \
5538 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
5539 spelling_size); \
5540 RESTORE_SPELLING_DEPTH (depth); \
5541 } \
5542 \
5543 spelling->kind = (KIND); \
5544 spelling->MEMBER = (VALUE); \
5545 spelling++; \
5546 }
5547
5548 /* Push STRING on the stack. Printed literally. */
5549
5550 static void
5551 push_string (const char *string)
5552 {
5553 PUSH_SPELLING (SPELLING_STRING, string, u.s);
5554 }
5555
5556 /* Push a member name on the stack. Printed as '.' STRING. */
5557
5558 static void
5559 push_member_name (tree decl)
5560 {
5561 const char *const string
5562 = (DECL_NAME (decl)
5563 ? identifier_to_locale (IDENTIFIER_POINTER (DECL_NAME (decl)))
5564 : _("<anonymous>"));
5565 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
5566 }
5567
5568 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
5569
5570 static void
5571 push_array_bounds (unsigned HOST_WIDE_INT bounds)
5572 {
5573 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
5574 }
5575
5576 /* Compute the maximum size in bytes of the printed spelling. */
5577
5578 static int
5579 spelling_length (void)
5580 {
5581 int size = 0;
5582 struct spelling *p;
5583
5584 for (p = spelling_base; p < spelling; p++)
5585 {
5586 if (p->kind == SPELLING_BOUNDS)
5587 size += 25;
5588 else
5589 size += strlen (p->u.s) + 1;
5590 }
5591
5592 return size;
5593 }
5594
5595 /* Print the spelling to BUFFER and return it. */
5596
5597 static char *
5598 print_spelling (char *buffer)
5599 {
5600 char *d = buffer;
5601 struct spelling *p;
5602
5603 for (p = spelling_base; p < spelling; p++)
5604 if (p->kind == SPELLING_BOUNDS)
5605 {
5606 sprintf (d, "[" HOST_WIDE_INT_PRINT_UNSIGNED "]", p->u.i);
5607 d += strlen (d);
5608 }
5609 else
5610 {
5611 const char *s;
5612 if (p->kind == SPELLING_MEMBER)
5613 *d++ = '.';
5614 for (s = p->u.s; (*d = *s++); d++)
5615 ;
5616 }
5617 *d++ = '\0';
5618 return buffer;
5619 }
5620
5621 /* Issue an error message for a bad initializer component.
5622 MSGID identifies the message.
5623 The component name is taken from the spelling stack. */
5624
5625 void
5626 error_init (const char *msgid)
5627 {
5628 char *ofwhat;
5629
5630 error ("%s", _(msgid));
5631 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
5632 if (*ofwhat)
5633 error ("(near initialization for %qs)", ofwhat);
5634 }
5635
5636 /* Issue a pedantic warning for a bad initializer component. OPT is
5637 the option OPT_* (from options.h) controlling this warning or 0 if
5638 it is unconditionally given. MSGID identifies the message. The
5639 component name is taken from the spelling stack. */
5640
5641 void
5642 pedwarn_init (location_t location, int opt, const char *msgid)
5643 {
5644 char *ofwhat;
5645
5646 pedwarn (location, opt, "%s", _(msgid));
5647 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
5648 if (*ofwhat)
5649 pedwarn (location, opt, "(near initialization for %qs)", ofwhat);
5650 }
5651
5652 /* Issue a warning for a bad initializer component.
5653
5654 OPT is the OPT_W* value corresponding to the warning option that
5655 controls this warning. MSGID identifies the message. The
5656 component name is taken from the spelling stack. */
5657
5658 static void
5659 warning_init (int opt, const char *msgid)
5660 {
5661 char *ofwhat;
5662
5663 warning (opt, "%s", _(msgid));
5664 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
5665 if (*ofwhat)
5666 warning (opt, "(near initialization for %qs)", ofwhat);
5667 }
5668 \f
5669 /* If TYPE is an array type and EXPR is a parenthesized string
5670 constant, warn if pedantic that EXPR is being used to initialize an
5671 object of type TYPE. */
5672
5673 void
5674 maybe_warn_string_init (tree type, struct c_expr expr)
5675 {
5676 if (pedantic
5677 && TREE_CODE (type) == ARRAY_TYPE
5678 && TREE_CODE (expr.value) == STRING_CST
5679 && expr.original_code != STRING_CST)
5680 pedwarn_init (input_location, OPT_pedantic,
5681 "array initialized from parenthesized string constant");
5682 }
5683
5684 /* Digest the parser output INIT as an initializer for type TYPE.
5685 Return a C expression of type TYPE to represent the initial value.
5686
5687 If ORIGTYPE is not NULL_TREE, it is the original type of INIT.
5688
5689 NULL_POINTER_CONSTANT is true if INIT is a null pointer constant.
5690
5691 If INIT is a string constant, STRICT_STRING is true if it is
5692 unparenthesized or we should not warn here for it being parenthesized.
5693 For other types of INIT, STRICT_STRING is not used.
5694
5695 INIT_LOC is the location of the INIT.
5696
5697 REQUIRE_CONSTANT requests an error if non-constant initializers or
5698 elements are seen. */
5699
5700 static tree
5701 digest_init (location_t init_loc, tree type, tree init, tree origtype,
5702 bool null_pointer_constant, bool strict_string,
5703 int require_constant)
5704 {
5705 enum tree_code code = TREE_CODE (type);
5706 tree inside_init = init;
5707 tree semantic_type = NULL_TREE;
5708 bool maybe_const = true;
5709
5710 if (type == error_mark_node
5711 || !init
5712 || init == error_mark_node
5713 || TREE_TYPE (init) == error_mark_node)
5714 return error_mark_node;
5715
5716 STRIP_TYPE_NOPS (inside_init);
5717
5718 if (TREE_CODE (inside_init) == EXCESS_PRECISION_EXPR)
5719 {
5720 semantic_type = TREE_TYPE (inside_init);
5721 inside_init = TREE_OPERAND (inside_init, 0);
5722 }
5723 inside_init = c_fully_fold (inside_init, require_constant, &maybe_const);
5724 inside_init = decl_constant_value_for_optimization (inside_init);
5725
5726 /* Initialization of an array of chars from a string constant
5727 optionally enclosed in braces. */
5728
5729 if (code == ARRAY_TYPE && inside_init
5730 && TREE_CODE (inside_init) == STRING_CST)
5731 {
5732 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
5733 /* Note that an array could be both an array of character type
5734 and an array of wchar_t if wchar_t is signed char or unsigned
5735 char. */
5736 bool char_array = (typ1 == char_type_node
5737 || typ1 == signed_char_type_node
5738 || typ1 == unsigned_char_type_node);
5739 bool wchar_array = !!comptypes (typ1, wchar_type_node);
5740 bool char16_array = !!comptypes (typ1, char16_type_node);
5741 bool char32_array = !!comptypes (typ1, char32_type_node);
5742
5743 if (char_array || wchar_array || char16_array || char32_array)
5744 {
5745 struct c_expr expr;
5746 tree typ2 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)));
5747 expr.value = inside_init;
5748 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
5749 expr.original_type = NULL;
5750 maybe_warn_string_init (type, expr);
5751
5752 if (TYPE_DOMAIN (type) && !TYPE_MAX_VALUE (TYPE_DOMAIN (type)))
5753 pedwarn_init (init_loc, OPT_pedantic,
5754 "initialization of a flexible array member");
5755
5756 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
5757 TYPE_MAIN_VARIANT (type)))
5758 return inside_init;
5759
5760 if (char_array)
5761 {
5762 if (typ2 != char_type_node)
5763 {
5764 error_init ("char-array initialized from wide string");
5765 return error_mark_node;
5766 }
5767 }
5768 else
5769 {
5770 if (typ2 == char_type_node)
5771 {
5772 error_init ("wide character array initialized from non-wide "
5773 "string");
5774 return error_mark_node;
5775 }
5776 else if (!comptypes(typ1, typ2))
5777 {
5778 error_init ("wide character array initialized from "
5779 "incompatible wide string");
5780 return error_mark_node;
5781 }
5782 }
5783
5784 TREE_TYPE (inside_init) = type;
5785 if (TYPE_DOMAIN (type) != 0
5786 && TYPE_SIZE (type) != 0
5787 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
5788 {
5789 unsigned HOST_WIDE_INT len = TREE_STRING_LENGTH (inside_init);
5790
5791 /* Subtract the size of a single (possibly wide) character
5792 because it's ok to ignore the terminating null char
5793 that is counted in the length of the constant. */
5794 if (0 > compare_tree_int (TYPE_SIZE_UNIT (type),
5795 (len
5796 - (TYPE_PRECISION (typ1)
5797 / BITS_PER_UNIT))))
5798 pedwarn_init (init_loc, 0,
5799 ("initializer-string for array of chars "
5800 "is too long"));
5801 else if (warn_cxx_compat
5802 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type), len))
5803 warning_at (init_loc, OPT_Wc___compat,
5804 ("initializer-string for array chars "
5805 "is too long for C++"));
5806 }
5807
5808 return inside_init;
5809 }
5810 else if (INTEGRAL_TYPE_P (typ1))
5811 {
5812 error_init ("array of inappropriate type initialized "
5813 "from string constant");
5814 return error_mark_node;
5815 }
5816 }
5817
5818 /* Build a VECTOR_CST from a *constant* vector constructor. If the
5819 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
5820 below and handle as a constructor. */
5821 if (code == VECTOR_TYPE
5822 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
5823 && vector_types_convertible_p (TREE_TYPE (inside_init), type, true)
5824 && TREE_CONSTANT (inside_init))
5825 {
5826 if (TREE_CODE (inside_init) == VECTOR_CST
5827 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
5828 TYPE_MAIN_VARIANT (type)))
5829 return inside_init;
5830
5831 if (TREE_CODE (inside_init) == CONSTRUCTOR)
5832 {
5833 unsigned HOST_WIDE_INT ix;
5834 tree value;
5835 bool constant_p = true;
5836
5837 /* Iterate through elements and check if all constructor
5838 elements are *_CSTs. */
5839 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (inside_init), ix, value)
5840 if (!CONSTANT_CLASS_P (value))
5841 {
5842 constant_p = false;
5843 break;
5844 }
5845
5846 if (constant_p)
5847 return build_vector_from_ctor (type,
5848 CONSTRUCTOR_ELTS (inside_init));
5849 }
5850 }
5851
5852 if (warn_sequence_point)
5853 verify_sequence_points (inside_init);
5854
5855 /* Any type can be initialized
5856 from an expression of the same type, optionally with braces. */
5857
5858 if (inside_init && TREE_TYPE (inside_init) != 0
5859 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
5860 TYPE_MAIN_VARIANT (type))
5861 || (code == ARRAY_TYPE
5862 && comptypes (TREE_TYPE (inside_init), type))
5863 || (code == VECTOR_TYPE
5864 && comptypes (TREE_TYPE (inside_init), type))
5865 || (code == POINTER_TYPE
5866 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
5867 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
5868 TREE_TYPE (type)))))
5869 {
5870 if (code == POINTER_TYPE)
5871 {
5872 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
5873 {
5874 if (TREE_CODE (inside_init) == STRING_CST
5875 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
5876 inside_init = array_to_pointer_conversion
5877 (init_loc, inside_init);
5878 else
5879 {
5880 error_init ("invalid use of non-lvalue array");
5881 return error_mark_node;
5882 }
5883 }
5884 }
5885
5886 if (code == VECTOR_TYPE)
5887 /* Although the types are compatible, we may require a
5888 conversion. */
5889 inside_init = convert (type, inside_init);
5890
5891 if (require_constant
5892 && (code == VECTOR_TYPE || !flag_isoc99)
5893 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
5894 {
5895 /* As an extension, allow initializing objects with static storage
5896 duration with compound literals (which are then treated just as
5897 the brace enclosed list they contain). Also allow this for
5898 vectors, as we can only assign them with compound literals. */
5899 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
5900 inside_init = DECL_INITIAL (decl);
5901 }
5902
5903 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
5904 && TREE_CODE (inside_init) != CONSTRUCTOR)
5905 {
5906 error_init ("array initialized from non-constant array expression");
5907 return error_mark_node;
5908 }
5909
5910 /* Compound expressions can only occur here if -pedantic or
5911 -pedantic-errors is specified. In the later case, we always want
5912 an error. In the former case, we simply want a warning. */
5913 if (require_constant && pedantic
5914 && TREE_CODE (inside_init) == COMPOUND_EXPR)
5915 {
5916 inside_init
5917 = valid_compound_expr_initializer (inside_init,
5918 TREE_TYPE (inside_init));
5919 if (inside_init == error_mark_node)
5920 error_init ("initializer element is not constant");
5921 else
5922 pedwarn_init (init_loc, OPT_pedantic,
5923 "initializer element is not constant");
5924 if (flag_pedantic_errors)
5925 inside_init = error_mark_node;
5926 }
5927 else if (require_constant
5928 && !initializer_constant_valid_p (inside_init,
5929 TREE_TYPE (inside_init)))
5930 {
5931 error_init ("initializer element is not constant");
5932 inside_init = error_mark_node;
5933 }
5934 else if (require_constant && !maybe_const)
5935 pedwarn_init (init_loc, 0,
5936 "initializer element is not a constant expression");
5937
5938 /* Added to enable additional -Wmissing-format-attribute warnings. */
5939 if (TREE_CODE (TREE_TYPE (inside_init)) == POINTER_TYPE)
5940 inside_init = convert_for_assignment (init_loc, type, inside_init,
5941 origtype,
5942 ic_init, null_pointer_constant,
5943 NULL_TREE, NULL_TREE, 0);
5944 return inside_init;
5945 }
5946
5947 /* Handle scalar types, including conversions. */
5948
5949 if (code == INTEGER_TYPE || code == REAL_TYPE || code == FIXED_POINT_TYPE
5950 || code == POINTER_TYPE || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE
5951 || code == COMPLEX_TYPE || code == VECTOR_TYPE)
5952 {
5953 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE
5954 && (TREE_CODE (init) == STRING_CST
5955 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR))
5956 inside_init = init = array_to_pointer_conversion (init_loc, init);
5957 if (semantic_type)
5958 inside_init = build1 (EXCESS_PRECISION_EXPR, semantic_type,
5959 inside_init);
5960 inside_init
5961 = convert_for_assignment (init_loc, type, inside_init, origtype,
5962 ic_init, null_pointer_constant,
5963 NULL_TREE, NULL_TREE, 0);
5964
5965 /* Check to see if we have already given an error message. */
5966 if (inside_init == error_mark_node)
5967 ;
5968 else if (require_constant && !TREE_CONSTANT (inside_init))
5969 {
5970 error_init ("initializer element is not constant");
5971 inside_init = error_mark_node;
5972 }
5973 else if (require_constant
5974 && !initializer_constant_valid_p (inside_init,
5975 TREE_TYPE (inside_init)))
5976 {
5977 error_init ("initializer element is not computable at load time");
5978 inside_init = error_mark_node;
5979 }
5980 else if (require_constant && !maybe_const)
5981 pedwarn_init (init_loc, 0,
5982 "initializer element is not a constant expression");
5983
5984 return inside_init;
5985 }
5986
5987 /* Come here only for records and arrays. */
5988
5989 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
5990 {
5991 error_init ("variable-sized object may not be initialized");
5992 return error_mark_node;
5993 }
5994
5995 error_init ("invalid initializer");
5996 return error_mark_node;
5997 }
5998 \f
5999 /* Handle initializers that use braces. */
6000
6001 /* Type of object we are accumulating a constructor for.
6002 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
6003 static tree constructor_type;
6004
6005 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
6006 left to fill. */
6007 static tree constructor_fields;
6008
6009 /* For an ARRAY_TYPE, this is the specified index
6010 at which to store the next element we get. */
6011 static tree constructor_index;
6012
6013 /* For an ARRAY_TYPE, this is the maximum index. */
6014 static tree constructor_max_index;
6015
6016 /* For a RECORD_TYPE, this is the first field not yet written out. */
6017 static tree constructor_unfilled_fields;
6018
6019 /* For an ARRAY_TYPE, this is the index of the first element
6020 not yet written out. */
6021 static tree constructor_unfilled_index;
6022
6023 /* In a RECORD_TYPE, the byte index of the next consecutive field.
6024 This is so we can generate gaps between fields, when appropriate. */
6025 static tree constructor_bit_index;
6026
6027 /* If we are saving up the elements rather than allocating them,
6028 this is the list of elements so far (in reverse order,
6029 most recent first). */
6030 static VEC(constructor_elt,gc) *constructor_elements;
6031
6032 /* 1 if constructor should be incrementally stored into a constructor chain,
6033 0 if all the elements should be kept in AVL tree. */
6034 static int constructor_incremental;
6035
6036 /* 1 if so far this constructor's elements are all compile-time constants. */
6037 static int constructor_constant;
6038
6039 /* 1 if so far this constructor's elements are all valid address constants. */
6040 static int constructor_simple;
6041
6042 /* 1 if this constructor has an element that cannot be part of a
6043 constant expression. */
6044 static int constructor_nonconst;
6045
6046 /* 1 if this constructor is erroneous so far. */
6047 static int constructor_erroneous;
6048
6049 /* Structure for managing pending initializer elements, organized as an
6050 AVL tree. */
6051
6052 struct init_node
6053 {
6054 struct init_node *left, *right;
6055 struct init_node *parent;
6056 int balance;
6057 tree purpose;
6058 tree value;
6059 tree origtype;
6060 };
6061
6062 /* Tree of pending elements at this constructor level.
6063 These are elements encountered out of order
6064 which belong at places we haven't reached yet in actually
6065 writing the output.
6066 Will never hold tree nodes across GC runs. */
6067 static struct init_node *constructor_pending_elts;
6068
6069 /* The SPELLING_DEPTH of this constructor. */
6070 static int constructor_depth;
6071
6072 /* DECL node for which an initializer is being read.
6073 0 means we are reading a constructor expression
6074 such as (struct foo) {...}. */
6075 static tree constructor_decl;
6076
6077 /* Nonzero if this is an initializer for a top-level decl. */
6078 static int constructor_top_level;
6079
6080 /* Nonzero if there were any member designators in this initializer. */
6081 static int constructor_designated;
6082
6083 /* Nesting depth of designator list. */
6084 static int designator_depth;
6085
6086 /* Nonzero if there were diagnosed errors in this designator list. */
6087 static int designator_erroneous;
6088
6089 \f
6090 /* This stack has a level for each implicit or explicit level of
6091 structuring in the initializer, including the outermost one. It
6092 saves the values of most of the variables above. */
6093
6094 struct constructor_range_stack;
6095
6096 struct constructor_stack
6097 {
6098 struct constructor_stack *next;
6099 tree type;
6100 tree fields;
6101 tree index;
6102 tree max_index;
6103 tree unfilled_index;
6104 tree unfilled_fields;
6105 tree bit_index;
6106 VEC(constructor_elt,gc) *elements;
6107 struct init_node *pending_elts;
6108 int offset;
6109 int depth;
6110 /* If value nonzero, this value should replace the entire
6111 constructor at this level. */
6112 struct c_expr replacement_value;
6113 struct constructor_range_stack *range_stack;
6114 char constant;
6115 char simple;
6116 char nonconst;
6117 char implicit;
6118 char erroneous;
6119 char outer;
6120 char incremental;
6121 char designated;
6122 };
6123
6124 static struct constructor_stack *constructor_stack;
6125
6126 /* This stack represents designators from some range designator up to
6127 the last designator in the list. */
6128
6129 struct constructor_range_stack
6130 {
6131 struct constructor_range_stack *next, *prev;
6132 struct constructor_stack *stack;
6133 tree range_start;
6134 tree index;
6135 tree range_end;
6136 tree fields;
6137 };
6138
6139 static struct constructor_range_stack *constructor_range_stack;
6140
6141 /* This stack records separate initializers that are nested.
6142 Nested initializers can't happen in ANSI C, but GNU C allows them
6143 in cases like { ... (struct foo) { ... } ... }. */
6144
6145 struct initializer_stack
6146 {
6147 struct initializer_stack *next;
6148 tree decl;
6149 struct constructor_stack *constructor_stack;
6150 struct constructor_range_stack *constructor_range_stack;
6151 VEC(constructor_elt,gc) *elements;
6152 struct spelling *spelling;
6153 struct spelling *spelling_base;
6154 int spelling_size;
6155 char top_level;
6156 char require_constant_value;
6157 char require_constant_elements;
6158 };
6159
6160 static struct initializer_stack *initializer_stack;
6161 \f
6162 /* Prepare to parse and output the initializer for variable DECL. */
6163
6164 void
6165 start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
6166 {
6167 const char *locus;
6168 struct initializer_stack *p = XNEW (struct initializer_stack);
6169
6170 p->decl = constructor_decl;
6171 p->require_constant_value = require_constant_value;
6172 p->require_constant_elements = require_constant_elements;
6173 p->constructor_stack = constructor_stack;
6174 p->constructor_range_stack = constructor_range_stack;
6175 p->elements = constructor_elements;
6176 p->spelling = spelling;
6177 p->spelling_base = spelling_base;
6178 p->spelling_size = spelling_size;
6179 p->top_level = constructor_top_level;
6180 p->next = initializer_stack;
6181 initializer_stack = p;
6182
6183 constructor_decl = decl;
6184 constructor_designated = 0;
6185 constructor_top_level = top_level;
6186
6187 if (decl != 0 && decl != error_mark_node)
6188 {
6189 require_constant_value = TREE_STATIC (decl);
6190 require_constant_elements
6191 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
6192 /* For a scalar, you can always use any value to initialize,
6193 even within braces. */
6194 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
6195 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
6196 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
6197 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
6198 locus = identifier_to_locale (IDENTIFIER_POINTER (DECL_NAME (decl)));
6199 }
6200 else
6201 {
6202 require_constant_value = 0;
6203 require_constant_elements = 0;
6204 locus = _("(anonymous)");
6205 }
6206
6207 constructor_stack = 0;
6208 constructor_range_stack = 0;
6209
6210 missing_braces_mentioned = 0;
6211
6212 spelling_base = 0;
6213 spelling_size = 0;
6214 RESTORE_SPELLING_DEPTH (0);
6215
6216 if (locus)
6217 push_string (locus);
6218 }
6219
6220 void
6221 finish_init (void)
6222 {
6223 struct initializer_stack *p = initializer_stack;
6224
6225 /* Free the whole constructor stack of this initializer. */
6226 while (constructor_stack)
6227 {
6228 struct constructor_stack *q = constructor_stack;
6229 constructor_stack = q->next;
6230 free (q);
6231 }
6232
6233 gcc_assert (!constructor_range_stack);
6234
6235 /* Pop back to the data of the outer initializer (if any). */
6236 free (spelling_base);
6237
6238 constructor_decl = p->decl;
6239 require_constant_value = p->require_constant_value;
6240 require_constant_elements = p->require_constant_elements;
6241 constructor_stack = p->constructor_stack;
6242 constructor_range_stack = p->constructor_range_stack;
6243 constructor_elements = p->elements;
6244 spelling = p->spelling;
6245 spelling_base = p->spelling_base;
6246 spelling_size = p->spelling_size;
6247 constructor_top_level = p->top_level;
6248 initializer_stack = p->next;
6249 free (p);
6250 }
6251 \f
6252 /* Call here when we see the initializer is surrounded by braces.
6253 This is instead of a call to push_init_level;
6254 it is matched by a call to pop_init_level.
6255
6256 TYPE is the type to initialize, for a constructor expression.
6257 For an initializer for a decl, TYPE is zero. */
6258
6259 void
6260 really_start_incremental_init (tree type)
6261 {
6262 struct constructor_stack *p = XNEW (struct constructor_stack);
6263
6264 if (type == 0)
6265 type = TREE_TYPE (constructor_decl);
6266
6267 if (TREE_CODE (type) == VECTOR_TYPE
6268 && TYPE_VECTOR_OPAQUE (type))
6269 error ("opaque vector types cannot be initialized");
6270
6271 p->type = constructor_type;
6272 p->fields = constructor_fields;
6273 p->index = constructor_index;
6274 p->max_index = constructor_max_index;
6275 p->unfilled_index = constructor_unfilled_index;
6276 p->unfilled_fields = constructor_unfilled_fields;
6277 p->bit_index = constructor_bit_index;
6278 p->elements = constructor_elements;
6279 p->constant = constructor_constant;
6280 p->simple = constructor_simple;
6281 p->nonconst = constructor_nonconst;
6282 p->erroneous = constructor_erroneous;
6283 p->pending_elts = constructor_pending_elts;
6284 p->depth = constructor_depth;
6285 p->replacement_value.value = 0;
6286 p->replacement_value.original_code = ERROR_MARK;
6287 p->replacement_value.original_type = NULL;
6288 p->implicit = 0;
6289 p->range_stack = 0;
6290 p->outer = 0;
6291 p->incremental = constructor_incremental;
6292 p->designated = constructor_designated;
6293 p->next = 0;
6294 constructor_stack = p;
6295
6296 constructor_constant = 1;
6297 constructor_simple = 1;
6298 constructor_nonconst = 0;
6299 constructor_depth = SPELLING_DEPTH ();
6300 constructor_elements = 0;
6301 constructor_pending_elts = 0;
6302 constructor_type = type;
6303 constructor_incremental = 1;
6304 constructor_designated = 0;
6305 designator_depth = 0;
6306 designator_erroneous = 0;
6307
6308 if (TREE_CODE (constructor_type) == RECORD_TYPE
6309 || TREE_CODE (constructor_type) == UNION_TYPE)
6310 {
6311 constructor_fields = TYPE_FIELDS (constructor_type);
6312 /* Skip any nameless bit fields at the beginning. */
6313 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
6314 && DECL_NAME (constructor_fields) == 0)
6315 constructor_fields = TREE_CHAIN (constructor_fields);
6316
6317 constructor_unfilled_fields = constructor_fields;
6318 constructor_bit_index = bitsize_zero_node;
6319 }
6320 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6321 {
6322 if (TYPE_DOMAIN (constructor_type))
6323 {
6324 constructor_max_index
6325 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
6326
6327 /* Detect non-empty initializations of zero-length arrays. */
6328 if (constructor_max_index == NULL_TREE
6329 && TYPE_SIZE (constructor_type))
6330 constructor_max_index = build_int_cst (NULL_TREE, -1);
6331
6332 /* constructor_max_index needs to be an INTEGER_CST. Attempts
6333 to initialize VLAs will cause a proper error; avoid tree
6334 checking errors as well by setting a safe value. */
6335 if (constructor_max_index
6336 && TREE_CODE (constructor_max_index) != INTEGER_CST)
6337 constructor_max_index = build_int_cst (NULL_TREE, -1);
6338
6339 constructor_index
6340 = convert (bitsizetype,
6341 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
6342 }
6343 else
6344 {
6345 constructor_index = bitsize_zero_node;
6346 constructor_max_index = NULL_TREE;
6347 }
6348
6349 constructor_unfilled_index = constructor_index;
6350 }
6351 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6352 {
6353 /* Vectors are like simple fixed-size arrays. */
6354 constructor_max_index =
6355 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
6356 constructor_index = bitsize_zero_node;
6357 constructor_unfilled_index = constructor_index;
6358 }
6359 else
6360 {
6361 /* Handle the case of int x = {5}; */
6362 constructor_fields = constructor_type;
6363 constructor_unfilled_fields = constructor_type;
6364 }
6365 }
6366 \f
6367 /* Push down into a subobject, for initialization.
6368 If this is for an explicit set of braces, IMPLICIT is 0.
6369 If it is because the next element belongs at a lower level,
6370 IMPLICIT is 1 (or 2 if the push is because of designator list). */
6371
6372 void
6373 push_init_level (int implicit)
6374 {
6375 struct constructor_stack *p;
6376 tree value = NULL_TREE;
6377
6378 /* If we've exhausted any levels that didn't have braces,
6379 pop them now. If implicit == 1, this will have been done in
6380 process_init_element; do not repeat it here because in the case
6381 of excess initializers for an empty aggregate this leads to an
6382 infinite cycle of popping a level and immediately recreating
6383 it. */
6384 if (implicit != 1)
6385 {
6386 while (constructor_stack->implicit)
6387 {
6388 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6389 || TREE_CODE (constructor_type) == UNION_TYPE)
6390 && constructor_fields == 0)
6391 process_init_element (pop_init_level (1), true);
6392 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6393 && constructor_max_index
6394 && tree_int_cst_lt (constructor_max_index,
6395 constructor_index))
6396 process_init_element (pop_init_level (1), true);
6397 else
6398 break;
6399 }
6400 }
6401
6402 /* Unless this is an explicit brace, we need to preserve previous
6403 content if any. */
6404 if (implicit)
6405 {
6406 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6407 || TREE_CODE (constructor_type) == UNION_TYPE)
6408 && constructor_fields)
6409 value = find_init_member (constructor_fields);
6410 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6411 value = find_init_member (constructor_index);
6412 }
6413
6414 p = XNEW (struct constructor_stack);
6415 p->type = constructor_type;
6416 p->fields = constructor_fields;
6417 p->index = constructor_index;
6418 p->max_index = constructor_max_index;
6419 p->unfilled_index = constructor_unfilled_index;
6420 p->unfilled_fields = constructor_unfilled_fields;
6421 p->bit_index = constructor_bit_index;
6422 p->elements = constructor_elements;
6423 p->constant = constructor_constant;
6424 p->simple = constructor_simple;
6425 p->nonconst = constructor_nonconst;
6426 p->erroneous = constructor_erroneous;
6427 p->pending_elts = constructor_pending_elts;
6428 p->depth = constructor_depth;
6429 p->replacement_value.value = 0;
6430 p->replacement_value.original_code = ERROR_MARK;
6431 p->replacement_value.original_type = NULL;
6432 p->implicit = implicit;
6433 p->outer = 0;
6434 p->incremental = constructor_incremental;
6435 p->designated = constructor_designated;
6436 p->next = constructor_stack;
6437 p->range_stack = 0;
6438 constructor_stack = p;
6439
6440 constructor_constant = 1;
6441 constructor_simple = 1;
6442 constructor_nonconst = 0;
6443 constructor_depth = SPELLING_DEPTH ();
6444 constructor_elements = 0;
6445 constructor_incremental = 1;
6446 constructor_designated = 0;
6447 constructor_pending_elts = 0;
6448 if (!implicit)
6449 {
6450 p->range_stack = constructor_range_stack;
6451 constructor_range_stack = 0;
6452 designator_depth = 0;
6453 designator_erroneous = 0;
6454 }
6455
6456 /* Don't die if an entire brace-pair level is superfluous
6457 in the containing level. */
6458 if (constructor_type == 0)
6459 ;
6460 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6461 || TREE_CODE (constructor_type) == UNION_TYPE)
6462 {
6463 /* Don't die if there are extra init elts at the end. */
6464 if (constructor_fields == 0)
6465 constructor_type = 0;
6466 else
6467 {
6468 constructor_type = TREE_TYPE (constructor_fields);
6469 push_member_name (constructor_fields);
6470 constructor_depth++;
6471 }
6472 }
6473 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6474 {
6475 constructor_type = TREE_TYPE (constructor_type);
6476 push_array_bounds (tree_low_cst (constructor_index, 1));
6477 constructor_depth++;
6478 }
6479
6480 if (constructor_type == 0)
6481 {
6482 error_init ("extra brace group at end of initializer");
6483 constructor_fields = 0;
6484 constructor_unfilled_fields = 0;
6485 return;
6486 }
6487
6488 if (value && TREE_CODE (value) == CONSTRUCTOR)
6489 {
6490 constructor_constant = TREE_CONSTANT (value);
6491 constructor_simple = TREE_STATIC (value);
6492 constructor_nonconst = CONSTRUCTOR_NON_CONST (value);
6493 constructor_elements = CONSTRUCTOR_ELTS (value);
6494 if (!VEC_empty (constructor_elt, constructor_elements)
6495 && (TREE_CODE (constructor_type) == RECORD_TYPE
6496 || TREE_CODE (constructor_type) == ARRAY_TYPE))
6497 set_nonincremental_init ();
6498 }
6499
6500 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
6501 {
6502 missing_braces_mentioned = 1;
6503 warning_init (OPT_Wmissing_braces, "missing braces around initializer");
6504 }
6505
6506 if (TREE_CODE (constructor_type) == RECORD_TYPE
6507 || TREE_CODE (constructor_type) == UNION_TYPE)
6508 {
6509 constructor_fields = TYPE_FIELDS (constructor_type);
6510 /* Skip any nameless bit fields at the beginning. */
6511 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
6512 && DECL_NAME (constructor_fields) == 0)
6513 constructor_fields = TREE_CHAIN (constructor_fields);
6514
6515 constructor_unfilled_fields = constructor_fields;
6516 constructor_bit_index = bitsize_zero_node;
6517 }
6518 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6519 {
6520 /* Vectors are like simple fixed-size arrays. */
6521 constructor_max_index =
6522 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
6523 constructor_index = convert (bitsizetype, integer_zero_node);
6524 constructor_unfilled_index = constructor_index;
6525 }
6526 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6527 {
6528 if (TYPE_DOMAIN (constructor_type))
6529 {
6530 constructor_max_index
6531 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
6532
6533 /* Detect non-empty initializations of zero-length arrays. */
6534 if (constructor_max_index == NULL_TREE
6535 && TYPE_SIZE (constructor_type))
6536 constructor_max_index = build_int_cst (NULL_TREE, -1);
6537
6538 /* constructor_max_index needs to be an INTEGER_CST. Attempts
6539 to initialize VLAs will cause a proper error; avoid tree
6540 checking errors as well by setting a safe value. */
6541 if (constructor_max_index
6542 && TREE_CODE (constructor_max_index) != INTEGER_CST)
6543 constructor_max_index = build_int_cst (NULL_TREE, -1);
6544
6545 constructor_index
6546 = convert (bitsizetype,
6547 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
6548 }
6549 else
6550 constructor_index = bitsize_zero_node;
6551
6552 constructor_unfilled_index = constructor_index;
6553 if (value && TREE_CODE (value) == STRING_CST)
6554 {
6555 /* We need to split the char/wchar array into individual
6556 characters, so that we don't have to special case it
6557 everywhere. */
6558 set_nonincremental_init_from_string (value);
6559 }
6560 }
6561 else
6562 {
6563 if (constructor_type != error_mark_node)
6564 warning_init (0, "braces around scalar initializer");
6565 constructor_fields = constructor_type;
6566 constructor_unfilled_fields = constructor_type;
6567 }
6568 }
6569
6570 /* At the end of an implicit or explicit brace level,
6571 finish up that level of constructor. If a single expression
6572 with redundant braces initialized that level, return the
6573 c_expr structure for that expression. Otherwise, the original_code
6574 element is set to ERROR_MARK.
6575 If we were outputting the elements as they are read, return 0 as the value
6576 from inner levels (process_init_element ignores that),
6577 but return error_mark_node as the value from the outermost level
6578 (that's what we want to put in DECL_INITIAL).
6579 Otherwise, return a CONSTRUCTOR expression as the value. */
6580
6581 struct c_expr
6582 pop_init_level (int implicit)
6583 {
6584 struct constructor_stack *p;
6585 struct c_expr ret;
6586 ret.value = 0;
6587 ret.original_code = ERROR_MARK;
6588 ret.original_type = NULL;
6589
6590 if (implicit == 0)
6591 {
6592 /* When we come to an explicit close brace,
6593 pop any inner levels that didn't have explicit braces. */
6594 while (constructor_stack->implicit)
6595 process_init_element (pop_init_level (1), true);
6596
6597 gcc_assert (!constructor_range_stack);
6598 }
6599
6600 /* Now output all pending elements. */
6601 constructor_incremental = 1;
6602 output_pending_init_elements (1);
6603
6604 p = constructor_stack;
6605
6606 /* Error for initializing a flexible array member, or a zero-length
6607 array member in an inappropriate context. */
6608 if (constructor_type && constructor_fields
6609 && TREE_CODE (constructor_type) == ARRAY_TYPE
6610 && TYPE_DOMAIN (constructor_type)
6611 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
6612 {
6613 /* Silently discard empty initializations. The parser will
6614 already have pedwarned for empty brackets. */
6615 if (integer_zerop (constructor_unfilled_index))
6616 constructor_type = NULL_TREE;
6617 else
6618 {
6619 gcc_assert (!TYPE_SIZE (constructor_type));
6620
6621 if (constructor_depth > 2)
6622 error_init ("initialization of flexible array member in a nested context");
6623 else
6624 pedwarn_init (input_location, OPT_pedantic,
6625 "initialization of a flexible array member");
6626
6627 /* We have already issued an error message for the existence
6628 of a flexible array member not at the end of the structure.
6629 Discard the initializer so that we do not die later. */
6630 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
6631 constructor_type = NULL_TREE;
6632 }
6633 }
6634
6635 /* Warn when some struct elements are implicitly initialized to zero. */
6636 if (warn_missing_field_initializers
6637 && constructor_type
6638 && TREE_CODE (constructor_type) == RECORD_TYPE
6639 && constructor_unfilled_fields)
6640 {
6641 /* Do not warn for flexible array members or zero-length arrays. */
6642 while (constructor_unfilled_fields
6643 && (!DECL_SIZE (constructor_unfilled_fields)
6644 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
6645 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
6646
6647 /* Do not warn if this level of the initializer uses member
6648 designators; it is likely to be deliberate. */
6649 if (constructor_unfilled_fields && !constructor_designated)
6650 {
6651 push_member_name (constructor_unfilled_fields);
6652 warning_init (OPT_Wmissing_field_initializers,
6653 "missing initializer");
6654 RESTORE_SPELLING_DEPTH (constructor_depth);
6655 }
6656 }
6657
6658 /* Pad out the end of the structure. */
6659 if (p->replacement_value.value)
6660 /* If this closes a superfluous brace pair,
6661 just pass out the element between them. */
6662 ret = p->replacement_value;
6663 else if (constructor_type == 0)
6664 ;
6665 else if (TREE_CODE (constructor_type) != RECORD_TYPE
6666 && TREE_CODE (constructor_type) != UNION_TYPE
6667 && TREE_CODE (constructor_type) != ARRAY_TYPE
6668 && TREE_CODE (constructor_type) != VECTOR_TYPE)
6669 {
6670 /* A nonincremental scalar initializer--just return
6671 the element, after verifying there is just one. */
6672 if (VEC_empty (constructor_elt,constructor_elements))
6673 {
6674 if (!constructor_erroneous)
6675 error_init ("empty scalar initializer");
6676 ret.value = error_mark_node;
6677 }
6678 else if (VEC_length (constructor_elt,constructor_elements) != 1)
6679 {
6680 error_init ("extra elements in scalar initializer");
6681 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
6682 }
6683 else
6684 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
6685 }
6686 else
6687 {
6688 if (constructor_erroneous)
6689 ret.value = error_mark_node;
6690 else
6691 {
6692 ret.value = build_constructor (constructor_type,
6693 constructor_elements);
6694 if (constructor_constant)
6695 TREE_CONSTANT (ret.value) = 1;
6696 if (constructor_constant && constructor_simple)
6697 TREE_STATIC (ret.value) = 1;
6698 if (constructor_nonconst)
6699 CONSTRUCTOR_NON_CONST (ret.value) = 1;
6700 }
6701 }
6702
6703 if (ret.value && TREE_CODE (ret.value) != CONSTRUCTOR)
6704 {
6705 if (constructor_nonconst)
6706 ret.original_code = C_MAYBE_CONST_EXPR;
6707 else if (ret.original_code == C_MAYBE_CONST_EXPR)
6708 ret.original_code = ERROR_MARK;
6709 }
6710
6711 constructor_type = p->type;
6712 constructor_fields = p->fields;
6713 constructor_index = p->index;
6714 constructor_max_index = p->max_index;
6715 constructor_unfilled_index = p->unfilled_index;
6716 constructor_unfilled_fields = p->unfilled_fields;
6717 constructor_bit_index = p->bit_index;
6718 constructor_elements = p->elements;
6719 constructor_constant = p->constant;
6720 constructor_simple = p->simple;
6721 constructor_nonconst = p->nonconst;
6722 constructor_erroneous = p->erroneous;
6723 constructor_incremental = p->incremental;
6724 constructor_designated = p->designated;
6725 constructor_pending_elts = p->pending_elts;
6726 constructor_depth = p->depth;
6727 if (!p->implicit)
6728 constructor_range_stack = p->range_stack;
6729 RESTORE_SPELLING_DEPTH (constructor_depth);
6730
6731 constructor_stack = p->next;
6732 free (p);
6733
6734 if (ret.value == 0 && constructor_stack == 0)
6735 ret.value = error_mark_node;
6736 return ret;
6737 }
6738
6739 /* Common handling for both array range and field name designators.
6740 ARRAY argument is nonzero for array ranges. Returns zero for success. */
6741
6742 static int
6743 set_designator (int array)
6744 {
6745 tree subtype;
6746 enum tree_code subcode;
6747
6748 /* Don't die if an entire brace-pair level is superfluous
6749 in the containing level. */
6750 if (constructor_type == 0)
6751 return 1;
6752
6753 /* If there were errors in this designator list already, bail out
6754 silently. */
6755 if (designator_erroneous)
6756 return 1;
6757
6758 if (!designator_depth)
6759 {
6760 gcc_assert (!constructor_range_stack);
6761
6762 /* Designator list starts at the level of closest explicit
6763 braces. */
6764 while (constructor_stack->implicit)
6765 process_init_element (pop_init_level (1), true);
6766 constructor_designated = 1;
6767 return 0;
6768 }
6769
6770 switch (TREE_CODE (constructor_type))
6771 {
6772 case RECORD_TYPE:
6773 case UNION_TYPE:
6774 subtype = TREE_TYPE (constructor_fields);
6775 if (subtype != error_mark_node)
6776 subtype = TYPE_MAIN_VARIANT (subtype);
6777 break;
6778 case ARRAY_TYPE:
6779 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6780 break;
6781 default:
6782 gcc_unreachable ();
6783 }
6784
6785 subcode = TREE_CODE (subtype);
6786 if (array && subcode != ARRAY_TYPE)
6787 {
6788 error_init ("array index in non-array initializer");
6789 return 1;
6790 }
6791 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
6792 {
6793 error_init ("field name not in record or union initializer");
6794 return 1;
6795 }
6796
6797 constructor_designated = 1;
6798 push_init_level (2);
6799 return 0;
6800 }
6801
6802 /* If there are range designators in designator list, push a new designator
6803 to constructor_range_stack. RANGE_END is end of such stack range or
6804 NULL_TREE if there is no range designator at this level. */
6805
6806 static void
6807 push_range_stack (tree range_end)
6808 {
6809 struct constructor_range_stack *p;
6810
6811 p = GGC_NEW (struct constructor_range_stack);
6812 p->prev = constructor_range_stack;
6813 p->next = 0;
6814 p->fields = constructor_fields;
6815 p->range_start = constructor_index;
6816 p->index = constructor_index;
6817 p->stack = constructor_stack;
6818 p->range_end = range_end;
6819 if (constructor_range_stack)
6820 constructor_range_stack->next = p;
6821 constructor_range_stack = p;
6822 }
6823
6824 /* Within an array initializer, specify the next index to be initialized.
6825 FIRST is that index. If LAST is nonzero, then initialize a range
6826 of indices, running from FIRST through LAST. */
6827
6828 void
6829 set_init_index (tree first, tree last)
6830 {
6831 if (set_designator (1))
6832 return;
6833
6834 designator_erroneous = 1;
6835
6836 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
6837 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
6838 {
6839 error_init ("array index in initializer not of integer type");
6840 return;
6841 }
6842
6843 if (TREE_CODE (first) != INTEGER_CST)
6844 {
6845 first = c_fully_fold (first, false, NULL);
6846 if (TREE_CODE (first) == INTEGER_CST)
6847 pedwarn_init (input_location, OPT_pedantic,
6848 "array index in initializer is not "
6849 "an integer constant expression");
6850 }
6851
6852 if (last && TREE_CODE (last) != INTEGER_CST)
6853 {
6854 last = c_fully_fold (last, false, NULL);
6855 if (TREE_CODE (last) == INTEGER_CST)
6856 pedwarn_init (input_location, OPT_pedantic,
6857 "array index in initializer is not "
6858 "an integer constant expression");
6859 }
6860
6861 if (TREE_CODE (first) != INTEGER_CST)
6862 error_init ("nonconstant array index in initializer");
6863 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
6864 error_init ("nonconstant array index in initializer");
6865 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
6866 error_init ("array index in non-array initializer");
6867 else if (tree_int_cst_sgn (first) == -1)
6868 error_init ("array index in initializer exceeds array bounds");
6869 else if (constructor_max_index
6870 && tree_int_cst_lt (constructor_max_index, first))
6871 error_init ("array index in initializer exceeds array bounds");
6872 else
6873 {
6874 constant_expression_warning (first);
6875 if (last)
6876 constant_expression_warning (last);
6877 constructor_index = convert (bitsizetype, first);
6878
6879 if (last)
6880 {
6881 if (tree_int_cst_equal (first, last))
6882 last = 0;
6883 else if (tree_int_cst_lt (last, first))
6884 {
6885 error_init ("empty index range in initializer");
6886 last = 0;
6887 }
6888 else
6889 {
6890 last = convert (bitsizetype, last);
6891 if (constructor_max_index != 0
6892 && tree_int_cst_lt (constructor_max_index, last))
6893 {
6894 error_init ("array index range in initializer exceeds array bounds");
6895 last = 0;
6896 }
6897 }
6898 }
6899
6900 designator_depth++;
6901 designator_erroneous = 0;
6902 if (constructor_range_stack || last)
6903 push_range_stack (last);
6904 }
6905 }
6906
6907 /* Within a struct initializer, specify the next field to be initialized. */
6908
6909 void
6910 set_init_label (tree fieldname)
6911 {
6912 tree tail;
6913
6914 if (set_designator (0))
6915 return;
6916
6917 designator_erroneous = 1;
6918
6919 if (TREE_CODE (constructor_type) != RECORD_TYPE
6920 && TREE_CODE (constructor_type) != UNION_TYPE)
6921 {
6922 error_init ("field name not in record or union initializer");
6923 return;
6924 }
6925
6926 for (tail = TYPE_FIELDS (constructor_type); tail;
6927 tail = TREE_CHAIN (tail))
6928 {
6929 if (DECL_NAME (tail) == fieldname)
6930 break;
6931 }
6932
6933 if (tail == 0)
6934 error ("unknown field %qE specified in initializer", fieldname);
6935 else
6936 {
6937 constructor_fields = tail;
6938 designator_depth++;
6939 designator_erroneous = 0;
6940 if (constructor_range_stack)
6941 push_range_stack (NULL_TREE);
6942 }
6943 }
6944 \f
6945 /* Add a new initializer to the tree of pending initializers. PURPOSE
6946 identifies the initializer, either array index or field in a structure.
6947 VALUE is the value of that index or field. If ORIGTYPE is not
6948 NULL_TREE, it is the original type of VALUE.
6949
6950 IMPLICIT is true if value comes from pop_init_level (1),
6951 the new initializer has been merged with the existing one
6952 and thus no warnings should be emitted about overriding an
6953 existing initializer. */
6954
6955 static void
6956 add_pending_init (tree purpose, tree value, tree origtype, bool implicit)
6957 {
6958 struct init_node *p, **q, *r;
6959
6960 q = &constructor_pending_elts;
6961 p = 0;
6962
6963 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6964 {
6965 while (*q != 0)
6966 {
6967 p = *q;
6968 if (tree_int_cst_lt (purpose, p->purpose))
6969 q = &p->left;
6970 else if (tree_int_cst_lt (p->purpose, purpose))
6971 q = &p->right;
6972 else
6973 {
6974 if (!implicit)
6975 {
6976 if (TREE_SIDE_EFFECTS (p->value))
6977 warning_init (0, "initialized field with side-effects overwritten");
6978 else if (warn_override_init)
6979 warning_init (OPT_Woverride_init, "initialized field overwritten");
6980 }
6981 p->value = value;
6982 p->origtype = origtype;
6983 return;
6984 }
6985 }
6986 }
6987 else
6988 {
6989 tree bitpos;
6990
6991 bitpos = bit_position (purpose);
6992 while (*q != NULL)
6993 {
6994 p = *q;
6995 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
6996 q = &p->left;
6997 else if (p->purpose != purpose)
6998 q = &p->right;
6999 else
7000 {
7001 if (!implicit)
7002 {
7003 if (TREE_SIDE_EFFECTS (p->value))
7004 warning_init (0, "initialized field with side-effects overwritten");
7005 else if (warn_override_init)
7006 warning_init (OPT_Woverride_init, "initialized field overwritten");
7007 }
7008 p->value = value;
7009 p->origtype = origtype;
7010 return;
7011 }
7012 }
7013 }
7014
7015 r = GGC_NEW (struct init_node);
7016 r->purpose = purpose;
7017 r->value = value;
7018 r->origtype = origtype;
7019
7020 *q = r;
7021 r->parent = p;
7022 r->left = 0;
7023 r->right = 0;
7024 r->balance = 0;
7025
7026 while (p)
7027 {
7028 struct init_node *s;
7029
7030 if (r == p->left)
7031 {
7032 if (p->balance == 0)
7033 p->balance = -1;
7034 else if (p->balance < 0)
7035 {
7036 if (r->balance < 0)
7037 {
7038 /* L rotation. */
7039 p->left = r->right;
7040 if (p->left)
7041 p->left->parent = p;
7042 r->right = p;
7043
7044 p->balance = 0;
7045 r->balance = 0;
7046
7047 s = p->parent;
7048 p->parent = r;
7049 r->parent = s;
7050 if (s)
7051 {
7052 if (s->left == p)
7053 s->left = r;
7054 else
7055 s->right = r;
7056 }
7057 else
7058 constructor_pending_elts = r;
7059 }
7060 else
7061 {
7062 /* LR rotation. */
7063 struct init_node *t = r->right;
7064
7065 r->right = t->left;
7066 if (r->right)
7067 r->right->parent = r;
7068 t->left = r;
7069
7070 p->left = t->right;
7071 if (p->left)
7072 p->left->parent = p;
7073 t->right = p;
7074
7075 p->balance = t->balance < 0;
7076 r->balance = -(t->balance > 0);
7077 t->balance = 0;
7078
7079 s = p->parent;
7080 p->parent = t;
7081 r->parent = t;
7082 t->parent = s;
7083 if (s)
7084 {
7085 if (s->left == p)
7086 s->left = t;
7087 else
7088 s->right = t;
7089 }
7090 else
7091 constructor_pending_elts = t;
7092 }
7093 break;
7094 }
7095 else
7096 {
7097 /* p->balance == +1; growth of left side balances the node. */
7098 p->balance = 0;
7099 break;
7100 }
7101 }
7102 else /* r == p->right */
7103 {
7104 if (p->balance == 0)
7105 /* Growth propagation from right side. */
7106 p->balance++;
7107 else if (p->balance > 0)
7108 {
7109 if (r->balance > 0)
7110 {
7111 /* R rotation. */
7112 p->right = r->left;
7113 if (p->right)
7114 p->right->parent = p;
7115 r->left = p;
7116
7117 p->balance = 0;
7118 r->balance = 0;
7119
7120 s = p->parent;
7121 p->parent = r;
7122 r->parent = s;
7123 if (s)
7124 {
7125 if (s->left == p)
7126 s->left = r;
7127 else
7128 s->right = r;
7129 }
7130 else
7131 constructor_pending_elts = r;
7132 }
7133 else /* r->balance == -1 */
7134 {
7135 /* RL rotation */
7136 struct init_node *t = r->left;
7137
7138 r->left = t->right;
7139 if (r->left)
7140 r->left->parent = r;
7141 t->right = r;
7142
7143 p->right = t->left;
7144 if (p->right)
7145 p->right->parent = p;
7146 t->left = p;
7147
7148 r->balance = (t->balance < 0);
7149 p->balance = -(t->balance > 0);
7150 t->balance = 0;
7151
7152 s = p->parent;
7153 p->parent = t;
7154 r->parent = t;
7155 t->parent = s;
7156 if (s)
7157 {
7158 if (s->left == p)
7159 s->left = t;
7160 else
7161 s->right = t;
7162 }
7163 else
7164 constructor_pending_elts = t;
7165 }
7166 break;
7167 }
7168 else
7169 {
7170 /* p->balance == -1; growth of right side balances the node. */
7171 p->balance = 0;
7172 break;
7173 }
7174 }
7175
7176 r = p;
7177 p = p->parent;
7178 }
7179 }
7180
7181 /* Build AVL tree from a sorted chain. */
7182
7183 static void
7184 set_nonincremental_init (void)
7185 {
7186 unsigned HOST_WIDE_INT ix;
7187 tree index, value;
7188
7189 if (TREE_CODE (constructor_type) != RECORD_TYPE
7190 && TREE_CODE (constructor_type) != ARRAY_TYPE)
7191 return;
7192
7193 FOR_EACH_CONSTRUCTOR_ELT (constructor_elements, ix, index, value)
7194 add_pending_init (index, value, NULL_TREE, false);
7195 constructor_elements = 0;
7196 if (TREE_CODE (constructor_type) == RECORD_TYPE)
7197 {
7198 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
7199 /* Skip any nameless bit fields at the beginning. */
7200 while (constructor_unfilled_fields != 0
7201 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
7202 && DECL_NAME (constructor_unfilled_fields) == 0)
7203 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
7204
7205 }
7206 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
7207 {
7208 if (TYPE_DOMAIN (constructor_type))
7209 constructor_unfilled_index
7210 = convert (bitsizetype,
7211 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
7212 else
7213 constructor_unfilled_index = bitsize_zero_node;
7214 }
7215 constructor_incremental = 0;
7216 }
7217
7218 /* Build AVL tree from a string constant. */
7219
7220 static void
7221 set_nonincremental_init_from_string (tree str)
7222 {
7223 tree value, purpose, type;
7224 HOST_WIDE_INT val[2];
7225 const char *p, *end;
7226 int byte, wchar_bytes, charwidth, bitpos;
7227
7228 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
7229
7230 wchar_bytes = TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str))) / BITS_PER_UNIT;
7231 charwidth = TYPE_PRECISION (char_type_node);
7232 type = TREE_TYPE (constructor_type);
7233 p = TREE_STRING_POINTER (str);
7234 end = p + TREE_STRING_LENGTH (str);
7235
7236 for (purpose = bitsize_zero_node;
7237 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
7238 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
7239 {
7240 if (wchar_bytes == 1)
7241 {
7242 val[1] = (unsigned char) *p++;
7243 val[0] = 0;
7244 }
7245 else
7246 {
7247 val[0] = 0;
7248 val[1] = 0;
7249 for (byte = 0; byte < wchar_bytes; byte++)
7250 {
7251 if (BYTES_BIG_ENDIAN)
7252 bitpos = (wchar_bytes - byte - 1) * charwidth;
7253 else
7254 bitpos = byte * charwidth;
7255 val[bitpos < HOST_BITS_PER_WIDE_INT]
7256 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
7257 << (bitpos % HOST_BITS_PER_WIDE_INT);
7258 }
7259 }
7260
7261 if (!TYPE_UNSIGNED (type))
7262 {
7263 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
7264 if (bitpos < HOST_BITS_PER_WIDE_INT)
7265 {
7266 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
7267 {
7268 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
7269 val[0] = -1;
7270 }
7271 }
7272 else if (bitpos == HOST_BITS_PER_WIDE_INT)
7273 {
7274 if (val[1] < 0)
7275 val[0] = -1;
7276 }
7277 else if (val[0] & (((HOST_WIDE_INT) 1)
7278 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
7279 val[0] |= ((HOST_WIDE_INT) -1)
7280 << (bitpos - HOST_BITS_PER_WIDE_INT);
7281 }
7282
7283 value = build_int_cst_wide (type, val[1], val[0]);
7284 add_pending_init (purpose, value, NULL_TREE, false);
7285 }
7286
7287 constructor_incremental = 0;
7288 }
7289
7290 /* Return value of FIELD in pending initializer or zero if the field was
7291 not initialized yet. */
7292
7293 static tree
7294 find_init_member (tree field)
7295 {
7296 struct init_node *p;
7297
7298 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
7299 {
7300 if (constructor_incremental
7301 && tree_int_cst_lt (field, constructor_unfilled_index))
7302 set_nonincremental_init ();
7303
7304 p = constructor_pending_elts;
7305 while (p)
7306 {
7307 if (tree_int_cst_lt (field, p->purpose))
7308 p = p->left;
7309 else if (tree_int_cst_lt (p->purpose, field))
7310 p = p->right;
7311 else
7312 return p->value;
7313 }
7314 }
7315 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
7316 {
7317 tree bitpos = bit_position (field);
7318
7319 if (constructor_incremental
7320 && (!constructor_unfilled_fields
7321 || tree_int_cst_lt (bitpos,
7322 bit_position (constructor_unfilled_fields))))
7323 set_nonincremental_init ();
7324
7325 p = constructor_pending_elts;
7326 while (p)
7327 {
7328 if (field == p->purpose)
7329 return p->value;
7330 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
7331 p = p->left;
7332 else
7333 p = p->right;
7334 }
7335 }
7336 else if (TREE_CODE (constructor_type) == UNION_TYPE)
7337 {
7338 if (!VEC_empty (constructor_elt, constructor_elements)
7339 && (VEC_last (constructor_elt, constructor_elements)->index
7340 == field))
7341 return VEC_last (constructor_elt, constructor_elements)->value;
7342 }
7343 return 0;
7344 }
7345
7346 /* "Output" the next constructor element.
7347 At top level, really output it to assembler code now.
7348 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
7349 If ORIGTYPE is not NULL_TREE, it is the original type of VALUE.
7350 TYPE is the data type that the containing data type wants here.
7351 FIELD is the field (a FIELD_DECL) or the index that this element fills.
7352 If VALUE is a string constant, STRICT_STRING is true if it is
7353 unparenthesized or we should not warn here for it being parenthesized.
7354 For other types of VALUE, STRICT_STRING is not used.
7355
7356 PENDING if non-nil means output pending elements that belong
7357 right after this element. (PENDING is normally 1;
7358 it is 0 while outputting pending elements, to avoid recursion.)
7359
7360 IMPLICIT is true if value comes from pop_init_level (1),
7361 the new initializer has been merged with the existing one
7362 and thus no warnings should be emitted about overriding an
7363 existing initializer. */
7364
7365 static void
7366 output_init_element (tree value, tree origtype, bool strict_string, tree type,
7367 tree field, int pending, bool implicit)
7368 {
7369 tree semantic_type = NULL_TREE;
7370 constructor_elt *celt;
7371 bool maybe_const = true;
7372 bool npc;
7373
7374 if (type == error_mark_node || value == error_mark_node)
7375 {
7376 constructor_erroneous = 1;
7377 return;
7378 }
7379 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
7380 && (TREE_CODE (value) == STRING_CST
7381 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR)
7382 && !(TREE_CODE (value) == STRING_CST
7383 && TREE_CODE (type) == ARRAY_TYPE
7384 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
7385 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
7386 TYPE_MAIN_VARIANT (type)))
7387 value = array_to_pointer_conversion (input_location, value);
7388
7389 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
7390 && require_constant_value && !flag_isoc99 && pending)
7391 {
7392 /* As an extension, allow initializing objects with static storage
7393 duration with compound literals (which are then treated just as
7394 the brace enclosed list they contain). */
7395 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
7396 value = DECL_INITIAL (decl);
7397 }
7398
7399 npc = null_pointer_constant_p (value);
7400 if (TREE_CODE (value) == EXCESS_PRECISION_EXPR)
7401 {
7402 semantic_type = TREE_TYPE (value);
7403 value = TREE_OPERAND (value, 0);
7404 }
7405 value = c_fully_fold (value, require_constant_value, &maybe_const);
7406
7407 if (value == error_mark_node)
7408 constructor_erroneous = 1;
7409 else if (!TREE_CONSTANT (value))
7410 constructor_constant = 0;
7411 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
7412 || ((TREE_CODE (constructor_type) == RECORD_TYPE
7413 || TREE_CODE (constructor_type) == UNION_TYPE)
7414 && DECL_C_BIT_FIELD (field)
7415 && TREE_CODE (value) != INTEGER_CST))
7416 constructor_simple = 0;
7417 if (!maybe_const)
7418 constructor_nonconst = 1;
7419
7420 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
7421 {
7422 if (require_constant_value)
7423 {
7424 error_init ("initializer element is not constant");
7425 value = error_mark_node;
7426 }
7427 else if (require_constant_elements)
7428 pedwarn (input_location, 0,
7429 "initializer element is not computable at load time");
7430 }
7431 else if (!maybe_const
7432 && (require_constant_value || require_constant_elements))
7433 pedwarn_init (input_location, 0,
7434 "initializer element is not a constant expression");
7435
7436 /* Issue -Wc++-compat warnings about initializing a bitfield with
7437 enum type. */
7438 if (warn_cxx_compat
7439 && field != NULL_TREE
7440 && TREE_CODE (field) == FIELD_DECL
7441 && DECL_BIT_FIELD_TYPE (field) != NULL_TREE
7442 && (TYPE_MAIN_VARIANT (DECL_BIT_FIELD_TYPE (field))
7443 != TYPE_MAIN_VARIANT (type))
7444 && TREE_CODE (DECL_BIT_FIELD_TYPE (field)) == ENUMERAL_TYPE)
7445 {
7446 tree checktype = origtype != NULL_TREE ? origtype : TREE_TYPE (value);
7447 if (checktype != error_mark_node
7448 && (TYPE_MAIN_VARIANT (checktype)
7449 != TYPE_MAIN_VARIANT (DECL_BIT_FIELD_TYPE (field))))
7450 warning_init (OPT_Wc___compat,
7451 "enum conversion in initialization is invalid in C++");
7452 }
7453
7454 /* If this field is empty (and not at the end of structure),
7455 don't do anything other than checking the initializer. */
7456 if (field
7457 && (TREE_TYPE (field) == error_mark_node
7458 || (COMPLETE_TYPE_P (TREE_TYPE (field))
7459 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
7460 && (TREE_CODE (constructor_type) == ARRAY_TYPE
7461 || TREE_CHAIN (field)))))
7462 return;
7463
7464 if (semantic_type)
7465 value = build1 (EXCESS_PRECISION_EXPR, semantic_type, value);
7466 value = digest_init (input_location, type, value, origtype, npc,
7467 strict_string, require_constant_value);
7468 if (value == error_mark_node)
7469 {
7470 constructor_erroneous = 1;
7471 return;
7472 }
7473 if (require_constant_value || require_constant_elements)
7474 constant_expression_warning (value);
7475
7476 /* If this element doesn't come next in sequence,
7477 put it on constructor_pending_elts. */
7478 if (TREE_CODE (constructor_type) == ARRAY_TYPE
7479 && (!constructor_incremental
7480 || !tree_int_cst_equal (field, constructor_unfilled_index)))
7481 {
7482 if (constructor_incremental
7483 && tree_int_cst_lt (field, constructor_unfilled_index))
7484 set_nonincremental_init ();
7485
7486 add_pending_init (field, value, origtype, implicit);
7487 return;
7488 }
7489 else if (TREE_CODE (constructor_type) == RECORD_TYPE
7490 && (!constructor_incremental
7491 || field != constructor_unfilled_fields))
7492 {
7493 /* We do this for records but not for unions. In a union,
7494 no matter which field is specified, it can be initialized
7495 right away since it starts at the beginning of the union. */
7496 if (constructor_incremental)
7497 {
7498 if (!constructor_unfilled_fields)
7499 set_nonincremental_init ();
7500 else
7501 {
7502 tree bitpos, unfillpos;
7503
7504 bitpos = bit_position (field);
7505 unfillpos = bit_position (constructor_unfilled_fields);
7506
7507 if (tree_int_cst_lt (bitpos, unfillpos))
7508 set_nonincremental_init ();
7509 }
7510 }
7511
7512 add_pending_init (field, value, origtype, implicit);
7513 return;
7514 }
7515 else if (TREE_CODE (constructor_type) == UNION_TYPE
7516 && !VEC_empty (constructor_elt, constructor_elements))
7517 {
7518 if (!implicit)
7519 {
7520 if (TREE_SIDE_EFFECTS (VEC_last (constructor_elt,
7521 constructor_elements)->value))
7522 warning_init (0,
7523 "initialized field with side-effects overwritten");
7524 else if (warn_override_init)
7525 warning_init (OPT_Woverride_init, "initialized field overwritten");
7526 }
7527
7528 /* We can have just one union field set. */
7529 constructor_elements = 0;
7530 }
7531
7532 /* Otherwise, output this element either to
7533 constructor_elements or to the assembler file. */
7534
7535 celt = VEC_safe_push (constructor_elt, gc, constructor_elements, NULL);
7536 celt->index = field;
7537 celt->value = value;
7538
7539 /* Advance the variable that indicates sequential elements output. */
7540 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
7541 constructor_unfilled_index
7542 = size_binop_loc (input_location, PLUS_EXPR, constructor_unfilled_index,
7543 bitsize_one_node);
7544 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
7545 {
7546 constructor_unfilled_fields
7547 = TREE_CHAIN (constructor_unfilled_fields);
7548
7549 /* Skip any nameless bit fields. */
7550 while (constructor_unfilled_fields != 0
7551 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
7552 && DECL_NAME (constructor_unfilled_fields) == 0)
7553 constructor_unfilled_fields =
7554 TREE_CHAIN (constructor_unfilled_fields);
7555 }
7556 else if (TREE_CODE (constructor_type) == UNION_TYPE)
7557 constructor_unfilled_fields = 0;
7558
7559 /* Now output any pending elements which have become next. */
7560 if (pending)
7561 output_pending_init_elements (0);
7562 }
7563
7564 /* Output any pending elements which have become next.
7565 As we output elements, constructor_unfilled_{fields,index}
7566 advances, which may cause other elements to become next;
7567 if so, they too are output.
7568
7569 If ALL is 0, we return when there are
7570 no more pending elements to output now.
7571
7572 If ALL is 1, we output space as necessary so that
7573 we can output all the pending elements. */
7574
7575 static void
7576 output_pending_init_elements (int all)
7577 {
7578 struct init_node *elt = constructor_pending_elts;
7579 tree next;
7580
7581 retry:
7582
7583 /* Look through the whole pending tree.
7584 If we find an element that should be output now,
7585 output it. Otherwise, set NEXT to the element
7586 that comes first among those still pending. */
7587
7588 next = 0;
7589 while (elt)
7590 {
7591 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
7592 {
7593 if (tree_int_cst_equal (elt->purpose,
7594 constructor_unfilled_index))
7595 output_init_element (elt->value, elt->origtype, true,
7596 TREE_TYPE (constructor_type),
7597 constructor_unfilled_index, 0, false);
7598 else if (tree_int_cst_lt (constructor_unfilled_index,
7599 elt->purpose))
7600 {
7601 /* Advance to the next smaller node. */
7602 if (elt->left)
7603 elt = elt->left;
7604 else
7605 {
7606 /* We have reached the smallest node bigger than the
7607 current unfilled index. Fill the space first. */
7608 next = elt->purpose;
7609 break;
7610 }
7611 }
7612 else
7613 {
7614 /* Advance to the next bigger node. */
7615 if (elt->right)
7616 elt = elt->right;
7617 else
7618 {
7619 /* We have reached the biggest node in a subtree. Find
7620 the parent of it, which is the next bigger node. */
7621 while (elt->parent && elt->parent->right == elt)
7622 elt = elt->parent;
7623 elt = elt->parent;
7624 if (elt && tree_int_cst_lt (constructor_unfilled_index,
7625 elt->purpose))
7626 {
7627 next = elt->purpose;
7628 break;
7629 }
7630 }
7631 }
7632 }
7633 else if (TREE_CODE (constructor_type) == RECORD_TYPE
7634 || TREE_CODE (constructor_type) == UNION_TYPE)
7635 {
7636 tree ctor_unfilled_bitpos, elt_bitpos;
7637
7638 /* If the current record is complete we are done. */
7639 if (constructor_unfilled_fields == 0)
7640 break;
7641
7642 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
7643 elt_bitpos = bit_position (elt->purpose);
7644 /* We can't compare fields here because there might be empty
7645 fields in between. */
7646 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
7647 {
7648 constructor_unfilled_fields = elt->purpose;
7649 output_init_element (elt->value, elt->origtype, true,
7650 TREE_TYPE (elt->purpose),
7651 elt->purpose, 0, false);
7652 }
7653 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
7654 {
7655 /* Advance to the next smaller node. */
7656 if (elt->left)
7657 elt = elt->left;
7658 else
7659 {
7660 /* We have reached the smallest node bigger than the
7661 current unfilled field. Fill the space first. */
7662 next = elt->purpose;
7663 break;
7664 }
7665 }
7666 else
7667 {
7668 /* Advance to the next bigger node. */
7669 if (elt->right)
7670 elt = elt->right;
7671 else
7672 {
7673 /* We have reached the biggest node in a subtree. Find
7674 the parent of it, which is the next bigger node. */
7675 while (elt->parent && elt->parent->right == elt)
7676 elt = elt->parent;
7677 elt = elt->parent;
7678 if (elt
7679 && (tree_int_cst_lt (ctor_unfilled_bitpos,
7680 bit_position (elt->purpose))))
7681 {
7682 next = elt->purpose;
7683 break;
7684 }
7685 }
7686 }
7687 }
7688 }
7689
7690 /* Ordinarily return, but not if we want to output all
7691 and there are elements left. */
7692 if (!(all && next != 0))
7693 return;
7694
7695 /* If it's not incremental, just skip over the gap, so that after
7696 jumping to retry we will output the next successive element. */
7697 if (TREE_CODE (constructor_type) == RECORD_TYPE
7698 || TREE_CODE (constructor_type) == UNION_TYPE)
7699 constructor_unfilled_fields = next;
7700 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
7701 constructor_unfilled_index = next;
7702
7703 /* ELT now points to the node in the pending tree with the next
7704 initializer to output. */
7705 goto retry;
7706 }
7707 \f
7708 /* Add one non-braced element to the current constructor level.
7709 This adjusts the current position within the constructor's type.
7710 This may also start or terminate implicit levels
7711 to handle a partly-braced initializer.
7712
7713 Once this has found the correct level for the new element,
7714 it calls output_init_element.
7715
7716 IMPLICIT is true if value comes from pop_init_level (1),
7717 the new initializer has been merged with the existing one
7718 and thus no warnings should be emitted about overriding an
7719 existing initializer. */
7720
7721 void
7722 process_init_element (struct c_expr value, bool implicit)
7723 {
7724 tree orig_value = value.value;
7725 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
7726 bool strict_string = value.original_code == STRING_CST;
7727
7728 designator_depth = 0;
7729 designator_erroneous = 0;
7730
7731 /* Handle superfluous braces around string cst as in
7732 char x[] = {"foo"}; */
7733 if (string_flag
7734 && constructor_type
7735 && TREE_CODE (constructor_type) == ARRAY_TYPE
7736 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
7737 && integer_zerop (constructor_unfilled_index))
7738 {
7739 if (constructor_stack->replacement_value.value)
7740 error_init ("excess elements in char array initializer");
7741 constructor_stack->replacement_value = value;
7742 return;
7743 }
7744
7745 if (constructor_stack->replacement_value.value != 0)
7746 {
7747 error_init ("excess elements in struct initializer");
7748 return;
7749 }
7750
7751 /* Ignore elements of a brace group if it is entirely superfluous
7752 and has already been diagnosed. */
7753 if (constructor_type == 0)
7754 return;
7755
7756 /* If we've exhausted any levels that didn't have braces,
7757 pop them now. */
7758 while (constructor_stack->implicit)
7759 {
7760 if ((TREE_CODE (constructor_type) == RECORD_TYPE
7761 || TREE_CODE (constructor_type) == UNION_TYPE)
7762 && constructor_fields == 0)
7763 process_init_element (pop_init_level (1), true);
7764 else if ((TREE_CODE (constructor_type) == ARRAY_TYPE
7765 || TREE_CODE (constructor_type) == VECTOR_TYPE)
7766 && (constructor_max_index == 0
7767 || tree_int_cst_lt (constructor_max_index,
7768 constructor_index)))
7769 process_init_element (pop_init_level (1), true);
7770 else
7771 break;
7772 }
7773
7774 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
7775 if (constructor_range_stack)
7776 {
7777 /* If value is a compound literal and we'll be just using its
7778 content, don't put it into a SAVE_EXPR. */
7779 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
7780 || !require_constant_value
7781 || flag_isoc99)
7782 {
7783 tree semantic_type = NULL_TREE;
7784 if (TREE_CODE (value.value) == EXCESS_PRECISION_EXPR)
7785 {
7786 semantic_type = TREE_TYPE (value.value);
7787 value.value = TREE_OPERAND (value.value, 0);
7788 }
7789 value.value = c_save_expr (value.value);
7790 if (semantic_type)
7791 value.value = build1 (EXCESS_PRECISION_EXPR, semantic_type,
7792 value.value);
7793 }
7794 }
7795
7796 while (1)
7797 {
7798 if (TREE_CODE (constructor_type) == RECORD_TYPE)
7799 {
7800 tree fieldtype;
7801 enum tree_code fieldcode;
7802
7803 if (constructor_fields == 0)
7804 {
7805 pedwarn_init (input_location, 0,
7806 "excess elements in struct initializer");
7807 break;
7808 }
7809
7810 fieldtype = TREE_TYPE (constructor_fields);
7811 if (fieldtype != error_mark_node)
7812 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
7813 fieldcode = TREE_CODE (fieldtype);
7814
7815 /* Error for non-static initialization of a flexible array member. */
7816 if (fieldcode == ARRAY_TYPE
7817 && !require_constant_value
7818 && TYPE_SIZE (fieldtype) == NULL_TREE
7819 && TREE_CHAIN (constructor_fields) == NULL_TREE)
7820 {
7821 error_init ("non-static initialization of a flexible array member");
7822 break;
7823 }
7824
7825 /* Accept a string constant to initialize a subarray. */
7826 if (value.value != 0
7827 && fieldcode == ARRAY_TYPE
7828 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
7829 && string_flag)
7830 value.value = orig_value;
7831 /* Otherwise, if we have come to a subaggregate,
7832 and we don't have an element of its type, push into it. */
7833 else if (value.value != 0
7834 && value.value != error_mark_node
7835 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
7836 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
7837 || fieldcode == UNION_TYPE || fieldcode == VECTOR_TYPE))
7838 {
7839 push_init_level (1);
7840 continue;
7841 }
7842
7843 if (value.value)
7844 {
7845 push_member_name (constructor_fields);
7846 output_init_element (value.value, value.original_type,
7847 strict_string, fieldtype,
7848 constructor_fields, 1, implicit);
7849 RESTORE_SPELLING_DEPTH (constructor_depth);
7850 }
7851 else
7852 /* Do the bookkeeping for an element that was
7853 directly output as a constructor. */
7854 {
7855 /* For a record, keep track of end position of last field. */
7856 if (DECL_SIZE (constructor_fields))
7857 constructor_bit_index
7858 = size_binop_loc (input_location, PLUS_EXPR,
7859 bit_position (constructor_fields),
7860 DECL_SIZE (constructor_fields));
7861
7862 /* If the current field was the first one not yet written out,
7863 it isn't now, so update. */
7864 if (constructor_unfilled_fields == constructor_fields)
7865 {
7866 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
7867 /* Skip any nameless bit fields. */
7868 while (constructor_unfilled_fields != 0
7869 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
7870 && DECL_NAME (constructor_unfilled_fields) == 0)
7871 constructor_unfilled_fields =
7872 TREE_CHAIN (constructor_unfilled_fields);
7873 }
7874 }
7875
7876 constructor_fields = TREE_CHAIN (constructor_fields);
7877 /* Skip any nameless bit fields at the beginning. */
7878 while (constructor_fields != 0
7879 && DECL_C_BIT_FIELD (constructor_fields)
7880 && DECL_NAME (constructor_fields) == 0)
7881 constructor_fields = TREE_CHAIN (constructor_fields);
7882 }
7883 else if (TREE_CODE (constructor_type) == UNION_TYPE)
7884 {
7885 tree fieldtype;
7886 enum tree_code fieldcode;
7887
7888 if (constructor_fields == 0)
7889 {
7890 pedwarn_init (input_location, 0,
7891 "excess elements in union initializer");
7892 break;
7893 }
7894
7895 fieldtype = TREE_TYPE (constructor_fields);
7896 if (fieldtype != error_mark_node)
7897 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
7898 fieldcode = TREE_CODE (fieldtype);
7899
7900 /* Warn that traditional C rejects initialization of unions.
7901 We skip the warning if the value is zero. This is done
7902 under the assumption that the zero initializer in user
7903 code appears conditioned on e.g. __STDC__ to avoid
7904 "missing initializer" warnings and relies on default
7905 initialization to zero in the traditional C case.
7906 We also skip the warning if the initializer is designated,
7907 again on the assumption that this must be conditional on
7908 __STDC__ anyway (and we've already complained about the
7909 member-designator already). */
7910 if (!in_system_header && !constructor_designated
7911 && !(value.value && (integer_zerop (value.value)
7912 || real_zerop (value.value))))
7913 warning (OPT_Wtraditional, "traditional C rejects initialization "
7914 "of unions");
7915
7916 /* Accept a string constant to initialize a subarray. */
7917 if (value.value != 0
7918 && fieldcode == ARRAY_TYPE
7919 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
7920 && string_flag)
7921 value.value = orig_value;
7922 /* Otherwise, if we have come to a subaggregate,
7923 and we don't have an element of its type, push into it. */
7924 else if (value.value != 0
7925 && value.value != error_mark_node
7926 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
7927 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
7928 || fieldcode == UNION_TYPE || fieldcode == VECTOR_TYPE))
7929 {
7930 push_init_level (1);
7931 continue;
7932 }
7933
7934 if (value.value)
7935 {
7936 push_member_name (constructor_fields);
7937 output_init_element (value.value, value.original_type,
7938 strict_string, fieldtype,
7939 constructor_fields, 1, implicit);
7940 RESTORE_SPELLING_DEPTH (constructor_depth);
7941 }
7942 else
7943 /* Do the bookkeeping for an element that was
7944 directly output as a constructor. */
7945 {
7946 constructor_bit_index = DECL_SIZE (constructor_fields);
7947 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
7948 }
7949
7950 constructor_fields = 0;
7951 }
7952 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
7953 {
7954 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
7955 enum tree_code eltcode = TREE_CODE (elttype);
7956
7957 /* Accept a string constant to initialize a subarray. */
7958 if (value.value != 0
7959 && eltcode == ARRAY_TYPE
7960 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
7961 && string_flag)
7962 value.value = orig_value;
7963 /* Otherwise, if we have come to a subaggregate,
7964 and we don't have an element of its type, push into it. */
7965 else if (value.value != 0
7966 && value.value != error_mark_node
7967 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
7968 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
7969 || eltcode == UNION_TYPE || eltcode == VECTOR_TYPE))
7970 {
7971 push_init_level (1);
7972 continue;
7973 }
7974
7975 if (constructor_max_index != 0
7976 && (tree_int_cst_lt (constructor_max_index, constructor_index)
7977 || integer_all_onesp (constructor_max_index)))
7978 {
7979 pedwarn_init (input_location, 0,
7980 "excess elements in array initializer");
7981 break;
7982 }
7983
7984 /* Now output the actual element. */
7985 if (value.value)
7986 {
7987 push_array_bounds (tree_low_cst (constructor_index, 1));
7988 output_init_element (value.value, value.original_type,
7989 strict_string, elttype,
7990 constructor_index, 1, implicit);
7991 RESTORE_SPELLING_DEPTH (constructor_depth);
7992 }
7993
7994 constructor_index
7995 = size_binop_loc (input_location, PLUS_EXPR,
7996 constructor_index, bitsize_one_node);
7997
7998 if (!value.value)
7999 /* If we are doing the bookkeeping for an element that was
8000 directly output as a constructor, we must update
8001 constructor_unfilled_index. */
8002 constructor_unfilled_index = constructor_index;
8003 }
8004 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
8005 {
8006 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
8007
8008 /* Do a basic check of initializer size. Note that vectors
8009 always have a fixed size derived from their type. */
8010 if (tree_int_cst_lt (constructor_max_index, constructor_index))
8011 {
8012 pedwarn_init (input_location, 0,
8013 "excess elements in vector initializer");
8014 break;
8015 }
8016
8017 /* Now output the actual element. */
8018 if (value.value)
8019 {
8020 if (TREE_CODE (value.value) == VECTOR_CST)
8021 elttype = TYPE_MAIN_VARIANT (constructor_type);
8022 output_init_element (value.value, value.original_type,
8023 strict_string, elttype,
8024 constructor_index, 1, implicit);
8025 }
8026
8027 constructor_index
8028 = size_binop_loc (input_location,
8029 PLUS_EXPR, constructor_index, bitsize_one_node);
8030
8031 if (!value.value)
8032 /* If we are doing the bookkeeping for an element that was
8033 directly output as a constructor, we must update
8034 constructor_unfilled_index. */
8035 constructor_unfilled_index = constructor_index;
8036 }
8037
8038 /* Handle the sole element allowed in a braced initializer
8039 for a scalar variable. */
8040 else if (constructor_type != error_mark_node
8041 && constructor_fields == 0)
8042 {
8043 pedwarn_init (input_location, 0,
8044 "excess elements in scalar initializer");
8045 break;
8046 }
8047 else
8048 {
8049 if (value.value)
8050 output_init_element (value.value, value.original_type,
8051 strict_string, constructor_type,
8052 NULL_TREE, 1, implicit);
8053 constructor_fields = 0;
8054 }
8055
8056 /* Handle range initializers either at this level or anywhere higher
8057 in the designator stack. */
8058 if (constructor_range_stack)
8059 {
8060 struct constructor_range_stack *p, *range_stack;
8061 int finish = 0;
8062
8063 range_stack = constructor_range_stack;
8064 constructor_range_stack = 0;
8065 while (constructor_stack != range_stack->stack)
8066 {
8067 gcc_assert (constructor_stack->implicit);
8068 process_init_element (pop_init_level (1), true);
8069 }
8070 for (p = range_stack;
8071 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
8072 p = p->prev)
8073 {
8074 gcc_assert (constructor_stack->implicit);
8075 process_init_element (pop_init_level (1), true);
8076 }
8077
8078 p->index = size_binop_loc (input_location,
8079 PLUS_EXPR, p->index, bitsize_one_node);
8080 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
8081 finish = 1;
8082
8083 while (1)
8084 {
8085 constructor_index = p->index;
8086 constructor_fields = p->fields;
8087 if (finish && p->range_end && p->index == p->range_start)
8088 {
8089 finish = 0;
8090 p->prev = 0;
8091 }
8092 p = p->next;
8093 if (!p)
8094 break;
8095 push_init_level (2);
8096 p->stack = constructor_stack;
8097 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
8098 p->index = p->range_start;
8099 }
8100
8101 if (!finish)
8102 constructor_range_stack = range_stack;
8103 continue;
8104 }
8105
8106 break;
8107 }
8108
8109 constructor_range_stack = 0;
8110 }
8111 \f
8112 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
8113 (guaranteed to be 'volatile' or null) and ARGS (represented using
8114 an ASM_EXPR node). */
8115 tree
8116 build_asm_stmt (tree cv_qualifier, tree args)
8117 {
8118 if (!ASM_VOLATILE_P (args) && cv_qualifier)
8119 ASM_VOLATILE_P (args) = 1;
8120 return add_stmt (args);
8121 }
8122
8123 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
8124 some INPUTS, and some CLOBBERS. The latter three may be NULL.
8125 SIMPLE indicates whether there was anything at all after the
8126 string in the asm expression -- asm("blah") and asm("blah" : )
8127 are subtly different. We use a ASM_EXPR node to represent this. */
8128 tree
8129 build_asm_expr (location_t loc, tree string, tree outputs, tree inputs,
8130 tree clobbers, tree labels, bool simple)
8131 {
8132 tree tail;
8133 tree args;
8134 int i;
8135 const char *constraint;
8136 const char **oconstraints;
8137 bool allows_mem, allows_reg, is_inout;
8138 int ninputs, noutputs;
8139
8140 ninputs = list_length (inputs);
8141 noutputs = list_length (outputs);
8142 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
8143
8144 string = resolve_asm_operand_names (string, outputs, inputs, labels);
8145
8146 /* Remove output conversions that change the type but not the mode. */
8147 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
8148 {
8149 tree output = TREE_VALUE (tail);
8150
8151 /* ??? Really, this should not be here. Users should be using a
8152 proper lvalue, dammit. But there's a long history of using casts
8153 in the output operands. In cases like longlong.h, this becomes a
8154 primitive form of typechecking -- if the cast can be removed, then
8155 the output operand had a type of the proper width; otherwise we'll
8156 get an error. Gross, but ... */
8157 STRIP_NOPS (output);
8158
8159 if (!lvalue_or_else (output, lv_asm))
8160 output = error_mark_node;
8161
8162 if (output != error_mark_node
8163 && (TREE_READONLY (output)
8164 || TYPE_READONLY (TREE_TYPE (output))
8165 || ((TREE_CODE (TREE_TYPE (output)) == RECORD_TYPE
8166 || TREE_CODE (TREE_TYPE (output)) == UNION_TYPE)
8167 && C_TYPE_FIELDS_READONLY (TREE_TYPE (output)))))
8168 readonly_error (output, lv_asm);
8169
8170 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
8171 oconstraints[i] = constraint;
8172
8173 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
8174 &allows_mem, &allows_reg, &is_inout))
8175 {
8176 /* If the operand is going to end up in memory,
8177 mark it addressable. */
8178 if (!allows_reg && !c_mark_addressable (output))
8179 output = error_mark_node;
8180 }
8181 else
8182 output = error_mark_node;
8183
8184 TREE_VALUE (tail) = output;
8185 }
8186
8187 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
8188 {
8189 tree input;
8190
8191 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
8192 input = TREE_VALUE (tail);
8193
8194 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
8195 oconstraints, &allows_mem, &allows_reg))
8196 {
8197 /* If the operand is going to end up in memory,
8198 mark it addressable. */
8199 if (!allows_reg && allows_mem)
8200 {
8201 /* Strip the nops as we allow this case. FIXME, this really
8202 should be rejected or made deprecated. */
8203 STRIP_NOPS (input);
8204 if (!c_mark_addressable (input))
8205 input = error_mark_node;
8206 }
8207 }
8208 else
8209 input = error_mark_node;
8210
8211 TREE_VALUE (tail) = input;
8212 }
8213
8214 /* ASMs with labels cannot have outputs. This should have been
8215 enforced by the parser. */
8216 gcc_assert (outputs == NULL || labels == NULL);
8217
8218 args = build_stmt (loc, ASM_EXPR, string, outputs, inputs, clobbers, labels);
8219
8220 /* asm statements without outputs, including simple ones, are treated
8221 as volatile. */
8222 ASM_INPUT_P (args) = simple;
8223 ASM_VOLATILE_P (args) = (noutputs == 0);
8224
8225 return args;
8226 }
8227 \f
8228 /* Generate a goto statement to LABEL. LOC is the location of the
8229 GOTO. */
8230
8231 tree
8232 c_finish_goto_label (location_t loc, tree label)
8233 {
8234 tree decl = lookup_label_for_goto (loc, label);
8235 if (!decl)
8236 return NULL_TREE;
8237 TREE_USED (decl) = 1;
8238 {
8239 tree t = build1 (GOTO_EXPR, void_type_node, decl);
8240 SET_EXPR_LOCATION (t, loc);
8241 return add_stmt (t);
8242 }
8243 }
8244
8245 /* Generate a computed goto statement to EXPR. LOC is the location of
8246 the GOTO. */
8247
8248 tree
8249 c_finish_goto_ptr (location_t loc, tree expr)
8250 {
8251 tree t;
8252 pedwarn (loc, OPT_pedantic, "ISO C forbids %<goto *expr;%>");
8253 expr = c_fully_fold (expr, false, NULL);
8254 expr = convert (ptr_type_node, expr);
8255 t = build1 (GOTO_EXPR, void_type_node, expr);
8256 SET_EXPR_LOCATION (t, loc);
8257 return add_stmt (t);
8258 }
8259
8260 /* Generate a C `return' statement. RETVAL is the expression for what
8261 to return, or a null pointer for `return;' with no value. LOC is
8262 the location of the return statement. If ORIGTYPE is not NULL_TREE, it
8263 is the original type of RETVAL. */
8264
8265 tree
8266 c_finish_return (location_t loc, tree retval, tree origtype)
8267 {
8268 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)), ret_stmt;
8269 bool no_warning = false;
8270 bool npc = false;
8271
8272 if (TREE_THIS_VOLATILE (current_function_decl))
8273 warning_at (loc, 0,
8274 "function declared %<noreturn%> has a %<return%> statement");
8275
8276 if (retval)
8277 {
8278 tree semantic_type = NULL_TREE;
8279 npc = null_pointer_constant_p (retval);
8280 if (TREE_CODE (retval) == EXCESS_PRECISION_EXPR)
8281 {
8282 semantic_type = TREE_TYPE (retval);
8283 retval = TREE_OPERAND (retval, 0);
8284 }
8285 retval = c_fully_fold (retval, false, NULL);
8286 if (semantic_type)
8287 retval = build1 (EXCESS_PRECISION_EXPR, semantic_type, retval);
8288 }
8289
8290 if (!retval)
8291 {
8292 current_function_returns_null = 1;
8293 if ((warn_return_type || flag_isoc99)
8294 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
8295 {
8296 pedwarn_c99 (loc, flag_isoc99 ? 0 : OPT_Wreturn_type,
8297 "%<return%> with no value, in "
8298 "function returning non-void");
8299 no_warning = true;
8300 }
8301 }
8302 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
8303 {
8304 current_function_returns_null = 1;
8305 if (TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
8306 pedwarn (loc, 0,
8307 "%<return%> with a value, in function returning void");
8308 else
8309 pedwarn (loc, OPT_pedantic, "ISO C forbids "
8310 "%<return%> with expression, in function returning void");
8311 }
8312 else
8313 {
8314 tree t = convert_for_assignment (loc, valtype, retval, origtype,
8315 ic_return,
8316 npc, NULL_TREE, NULL_TREE, 0);
8317 tree res = DECL_RESULT (current_function_decl);
8318 tree inner;
8319
8320 current_function_returns_value = 1;
8321 if (t == error_mark_node)
8322 return NULL_TREE;
8323
8324 inner = t = convert (TREE_TYPE (res), t);
8325
8326 /* Strip any conversions, additions, and subtractions, and see if
8327 we are returning the address of a local variable. Warn if so. */
8328 while (1)
8329 {
8330 switch (TREE_CODE (inner))
8331 {
8332 CASE_CONVERT:
8333 case NON_LVALUE_EXPR:
8334 case PLUS_EXPR:
8335 case POINTER_PLUS_EXPR:
8336 inner = TREE_OPERAND (inner, 0);
8337 continue;
8338
8339 case MINUS_EXPR:
8340 /* If the second operand of the MINUS_EXPR has a pointer
8341 type (or is converted from it), this may be valid, so
8342 don't give a warning. */
8343 {
8344 tree op1 = TREE_OPERAND (inner, 1);
8345
8346 while (!POINTER_TYPE_P (TREE_TYPE (op1))
8347 && (CONVERT_EXPR_P (op1)
8348 || TREE_CODE (op1) == NON_LVALUE_EXPR))
8349 op1 = TREE_OPERAND (op1, 0);
8350
8351 if (POINTER_TYPE_P (TREE_TYPE (op1)))
8352 break;
8353
8354 inner = TREE_OPERAND (inner, 0);
8355 continue;
8356 }
8357
8358 case ADDR_EXPR:
8359 inner = TREE_OPERAND (inner, 0);
8360
8361 while (REFERENCE_CLASS_P (inner)
8362 && TREE_CODE (inner) != INDIRECT_REF)
8363 inner = TREE_OPERAND (inner, 0);
8364
8365 if (DECL_P (inner)
8366 && !DECL_EXTERNAL (inner)
8367 && !TREE_STATIC (inner)
8368 && DECL_CONTEXT (inner) == current_function_decl)
8369 warning_at (loc,
8370 0, "function returns address of local variable");
8371 break;
8372
8373 default:
8374 break;
8375 }
8376
8377 break;
8378 }
8379
8380 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
8381 SET_EXPR_LOCATION (retval, loc);
8382
8383 if (warn_sequence_point)
8384 verify_sequence_points (retval);
8385 }
8386
8387 ret_stmt = build_stmt (loc, RETURN_EXPR, retval);
8388 TREE_NO_WARNING (ret_stmt) |= no_warning;
8389 return add_stmt (ret_stmt);
8390 }
8391 \f
8392 struct c_switch {
8393 /* The SWITCH_EXPR being built. */
8394 tree switch_expr;
8395
8396 /* The original type of the testing expression, i.e. before the
8397 default conversion is applied. */
8398 tree orig_type;
8399
8400 /* A splay-tree mapping the low element of a case range to the high
8401 element, or NULL_TREE if there is no high element. Used to
8402 determine whether or not a new case label duplicates an old case
8403 label. We need a tree, rather than simply a hash table, because
8404 of the GNU case range extension. */
8405 splay_tree cases;
8406
8407 /* The bindings at the point of the switch. This is used for
8408 warnings crossing decls when branching to a case label. */
8409 struct c_spot_bindings *bindings;
8410
8411 /* The next node on the stack. */
8412 struct c_switch *next;
8413 };
8414
8415 /* A stack of the currently active switch statements. The innermost
8416 switch statement is on the top of the stack. There is no need to
8417 mark the stack for garbage collection because it is only active
8418 during the processing of the body of a function, and we never
8419 collect at that point. */
8420
8421 struct c_switch *c_switch_stack;
8422
8423 /* Start a C switch statement, testing expression EXP. Return the new
8424 SWITCH_EXPR. SWITCH_LOC is the location of the `switch'.
8425 SWITCH_COND_LOC is the location of the switch's condition. */
8426
8427 tree
8428 c_start_case (location_t switch_loc,
8429 location_t switch_cond_loc,
8430 tree exp)
8431 {
8432 tree orig_type = error_mark_node;
8433 struct c_switch *cs;
8434
8435 if (exp != error_mark_node)
8436 {
8437 orig_type = TREE_TYPE (exp);
8438
8439 if (!INTEGRAL_TYPE_P (orig_type))
8440 {
8441 if (orig_type != error_mark_node)
8442 {
8443 error_at (switch_cond_loc, "switch quantity not an integer");
8444 orig_type = error_mark_node;
8445 }
8446 exp = integer_zero_node;
8447 }
8448 else
8449 {
8450 tree type = TYPE_MAIN_VARIANT (orig_type);
8451
8452 if (!in_system_header
8453 && (type == long_integer_type_node
8454 || type == long_unsigned_type_node))
8455 warning_at (switch_cond_loc,
8456 OPT_Wtraditional, "%<long%> switch expression not "
8457 "converted to %<int%> in ISO C");
8458
8459 exp = c_fully_fold (exp, false, NULL);
8460 exp = default_conversion (exp);
8461
8462 if (warn_sequence_point)
8463 verify_sequence_points (exp);
8464 }
8465 }
8466
8467 /* Add this new SWITCH_EXPR to the stack. */
8468 cs = XNEW (struct c_switch);
8469 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE);
8470 SET_EXPR_LOCATION (cs->switch_expr, switch_loc);
8471 cs->orig_type = orig_type;
8472 cs->cases = splay_tree_new (case_compare, NULL, NULL);
8473 cs->bindings = c_get_switch_bindings ();
8474 cs->next = c_switch_stack;
8475 c_switch_stack = cs;
8476
8477 return add_stmt (cs->switch_expr);
8478 }
8479
8480 /* Process a case label at location LOC. */
8481
8482 tree
8483 do_case (location_t loc, tree low_value, tree high_value)
8484 {
8485 tree label = NULL_TREE;
8486
8487 if (low_value && TREE_CODE (low_value) != INTEGER_CST)
8488 {
8489 low_value = c_fully_fold (low_value, false, NULL);
8490 if (TREE_CODE (low_value) == INTEGER_CST)
8491 pedwarn (input_location, OPT_pedantic,
8492 "case label is not an integer constant expression");
8493 }
8494
8495 if (high_value && TREE_CODE (high_value) != INTEGER_CST)
8496 {
8497 high_value = c_fully_fold (high_value, false, NULL);
8498 if (TREE_CODE (high_value) == INTEGER_CST)
8499 pedwarn (input_location, OPT_pedantic,
8500 "case label is not an integer constant expression");
8501 }
8502
8503 if (c_switch_stack == NULL)
8504 {
8505 if (low_value)
8506 error_at (loc, "case label not within a switch statement");
8507 else
8508 error_at (loc, "%<default%> label not within a switch statement");
8509 return NULL_TREE;
8510 }
8511
8512 if (c_check_switch_jump_warnings (c_switch_stack->bindings,
8513 EXPR_LOCATION (c_switch_stack->switch_expr),
8514 loc))
8515 return NULL_TREE;
8516
8517 label = c_add_case_label (loc, c_switch_stack->cases,
8518 SWITCH_COND (c_switch_stack->switch_expr),
8519 c_switch_stack->orig_type,
8520 low_value, high_value);
8521 if (label == error_mark_node)
8522 label = NULL_TREE;
8523 return label;
8524 }
8525
8526 /* Finish the switch statement. */
8527
8528 void
8529 c_finish_case (tree body)
8530 {
8531 struct c_switch *cs = c_switch_stack;
8532 location_t switch_location;
8533
8534 SWITCH_BODY (cs->switch_expr) = body;
8535
8536 /* Emit warnings as needed. */
8537 switch_location = EXPR_LOCATION (cs->switch_expr);
8538 c_do_switch_warnings (cs->cases, switch_location,
8539 TREE_TYPE (cs->switch_expr),
8540 SWITCH_COND (cs->switch_expr));
8541
8542 /* Pop the stack. */
8543 c_switch_stack = cs->next;
8544 splay_tree_delete (cs->cases);
8545 c_release_switch_bindings (cs->bindings);
8546 XDELETE (cs);
8547 }
8548 \f
8549 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
8550 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
8551 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
8552 statement, and was not surrounded with parenthesis. */
8553
8554 void
8555 c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
8556 tree else_block, bool nested_if)
8557 {
8558 tree stmt;
8559
8560 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
8561 if (warn_parentheses && nested_if && else_block == NULL)
8562 {
8563 tree inner_if = then_block;
8564
8565 /* We know from the grammar productions that there is an IF nested
8566 within THEN_BLOCK. Due to labels and c99 conditional declarations,
8567 it might not be exactly THEN_BLOCK, but should be the last
8568 non-container statement within. */
8569 while (1)
8570 switch (TREE_CODE (inner_if))
8571 {
8572 case COND_EXPR:
8573 goto found;
8574 case BIND_EXPR:
8575 inner_if = BIND_EXPR_BODY (inner_if);
8576 break;
8577 case STATEMENT_LIST:
8578 inner_if = expr_last (then_block);
8579 break;
8580 case TRY_FINALLY_EXPR:
8581 case TRY_CATCH_EXPR:
8582 inner_if = TREE_OPERAND (inner_if, 0);
8583 break;
8584 default:
8585 gcc_unreachable ();
8586 }
8587 found:
8588
8589 if (COND_EXPR_ELSE (inner_if))
8590 warning_at (if_locus, OPT_Wparentheses,
8591 "suggest explicit braces to avoid ambiguous %<else%>");
8592 }
8593
8594 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block);
8595 SET_EXPR_LOCATION (stmt, if_locus);
8596 add_stmt (stmt);
8597 }
8598
8599 /* Emit a general-purpose loop construct. START_LOCUS is the location of
8600 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
8601 is false for DO loops. INCR is the FOR increment expression. BODY is
8602 the statement controlled by the loop. BLAB is the break label. CLAB is
8603 the continue label. Everything is allowed to be NULL. */
8604
8605 void
8606 c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
8607 tree blab, tree clab, bool cond_is_first)
8608 {
8609 tree entry = NULL, exit = NULL, t;
8610
8611 /* If the condition is zero don't generate a loop construct. */
8612 if (cond && integer_zerop (cond))
8613 {
8614 if (cond_is_first)
8615 {
8616 t = build_and_jump (&blab);
8617 SET_EXPR_LOCATION (t, start_locus);
8618 add_stmt (t);
8619 }
8620 }
8621 else
8622 {
8623 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
8624
8625 /* If we have an exit condition, then we build an IF with gotos either
8626 out of the loop, or to the top of it. If there's no exit condition,
8627 then we just build a jump back to the top. */
8628 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
8629
8630 if (cond && !integer_nonzerop (cond))
8631 {
8632 /* Canonicalize the loop condition to the end. This means
8633 generating a branch to the loop condition. Reuse the
8634 continue label, if possible. */
8635 if (cond_is_first)
8636 {
8637 if (incr || !clab)
8638 {
8639 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
8640 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
8641 }
8642 else
8643 t = build1 (GOTO_EXPR, void_type_node, clab);
8644 SET_EXPR_LOCATION (t, start_locus);
8645 add_stmt (t);
8646 }
8647
8648 t = build_and_jump (&blab);
8649 if (cond_is_first)
8650 exit = fold_build3_loc (start_locus,
8651 COND_EXPR, void_type_node, cond, exit, t);
8652 else
8653 exit = fold_build3_loc (input_location,
8654 COND_EXPR, void_type_node, cond, exit, t);
8655 }
8656
8657 add_stmt (top);
8658 }
8659
8660 if (body)
8661 add_stmt (body);
8662 if (clab)
8663 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
8664 if (incr)
8665 add_stmt (incr);
8666 if (entry)
8667 add_stmt (entry);
8668 if (exit)
8669 add_stmt (exit);
8670 if (blab)
8671 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
8672 }
8673
8674 tree
8675 c_finish_bc_stmt (location_t loc, tree *label_p, bool is_break)
8676 {
8677 bool skip;
8678 tree label = *label_p;
8679
8680 /* In switch statements break is sometimes stylistically used after
8681 a return statement. This can lead to spurious warnings about
8682 control reaching the end of a non-void function when it is
8683 inlined. Note that we are calling block_may_fallthru with
8684 language specific tree nodes; this works because
8685 block_may_fallthru returns true when given something it does not
8686 understand. */
8687 skip = !block_may_fallthru (cur_stmt_list);
8688
8689 if (!label)
8690 {
8691 if (!skip)
8692 *label_p = label = create_artificial_label (loc);
8693 }
8694 else if (TREE_CODE (label) == LABEL_DECL)
8695 ;
8696 else switch (TREE_INT_CST_LOW (label))
8697 {
8698 case 0:
8699 if (is_break)
8700 error_at (loc, "break statement not within loop or switch");
8701 else
8702 error_at (loc, "continue statement not within a loop");
8703 return NULL_TREE;
8704
8705 case 1:
8706 gcc_assert (is_break);
8707 error_at (loc, "break statement used with OpenMP for loop");
8708 return NULL_TREE;
8709
8710 default:
8711 gcc_unreachable ();
8712 }
8713
8714 if (skip)
8715 return NULL_TREE;
8716
8717 if (!is_break)
8718 add_stmt (build_predict_expr (PRED_CONTINUE, NOT_TAKEN));
8719
8720 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
8721 }
8722
8723 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
8724
8725 static void
8726 emit_side_effect_warnings (location_t loc, tree expr)
8727 {
8728 if (expr == error_mark_node)
8729 ;
8730 else if (!TREE_SIDE_EFFECTS (expr))
8731 {
8732 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
8733 warning_at (loc, OPT_Wunused_value, "statement with no effect");
8734 }
8735 else
8736 warn_if_unused_value (expr, loc);
8737 }
8738
8739 /* Process an expression as if it were a complete statement. Emit
8740 diagnostics, but do not call ADD_STMT. LOC is the location of the
8741 statement. */
8742
8743 tree
8744 c_process_expr_stmt (location_t loc, tree expr)
8745 {
8746 if (!expr)
8747 return NULL_TREE;
8748
8749 expr = c_fully_fold (expr, false, NULL);
8750
8751 if (warn_sequence_point)
8752 verify_sequence_points (expr);
8753
8754 if (TREE_TYPE (expr) != error_mark_node
8755 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
8756 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
8757 error_at (loc, "expression statement has incomplete type");
8758
8759 /* If we're not processing a statement expression, warn about unused values.
8760 Warnings for statement expressions will be emitted later, once we figure
8761 out which is the result. */
8762 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
8763 && warn_unused_value)
8764 emit_side_effect_warnings (loc, expr);
8765
8766 /* If the expression is not of a type to which we cannot assign a line
8767 number, wrap the thing in a no-op NOP_EXPR. */
8768 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
8769 {
8770 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
8771 SET_EXPR_LOCATION (expr, loc);
8772 }
8773
8774 return expr;
8775 }
8776
8777 /* Emit an expression as a statement. LOC is the location of the
8778 expression. */
8779
8780 tree
8781 c_finish_expr_stmt (location_t loc, tree expr)
8782 {
8783 if (expr)
8784 return add_stmt (c_process_expr_stmt (loc, expr));
8785 else
8786 return NULL;
8787 }
8788
8789 /* Do the opposite and emit a statement as an expression. To begin,
8790 create a new binding level and return it. */
8791
8792 tree
8793 c_begin_stmt_expr (void)
8794 {
8795 tree ret;
8796
8797 /* We must force a BLOCK for this level so that, if it is not expanded
8798 later, there is a way to turn off the entire subtree of blocks that
8799 are contained in it. */
8800 keep_next_level ();
8801 ret = c_begin_compound_stmt (true);
8802
8803 c_bindings_start_stmt_expr (c_switch_stack == NULL
8804 ? NULL
8805 : c_switch_stack->bindings);
8806
8807 /* Mark the current statement list as belonging to a statement list. */
8808 STATEMENT_LIST_STMT_EXPR (ret) = 1;
8809
8810 return ret;
8811 }
8812
8813 /* LOC is the location of the compound statement to which this body
8814 belongs. */
8815
8816 tree
8817 c_finish_stmt_expr (location_t loc, tree body)
8818 {
8819 tree last, type, tmp, val;
8820 tree *last_p;
8821
8822 body = c_end_compound_stmt (loc, body, true);
8823
8824 c_bindings_end_stmt_expr (c_switch_stack == NULL
8825 ? NULL
8826 : c_switch_stack->bindings);
8827
8828 /* Locate the last statement in BODY. See c_end_compound_stmt
8829 about always returning a BIND_EXPR. */
8830 last_p = &BIND_EXPR_BODY (body);
8831 last = BIND_EXPR_BODY (body);
8832
8833 continue_searching:
8834 if (TREE_CODE (last) == STATEMENT_LIST)
8835 {
8836 tree_stmt_iterator i;
8837
8838 /* This can happen with degenerate cases like ({ }). No value. */
8839 if (!TREE_SIDE_EFFECTS (last))
8840 return body;
8841
8842 /* If we're supposed to generate side effects warnings, process
8843 all of the statements except the last. */
8844 if (warn_unused_value)
8845 {
8846 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
8847 {
8848 location_t tloc;
8849 tree t = tsi_stmt (i);
8850
8851 tloc = EXPR_HAS_LOCATION (t) ? EXPR_LOCATION (t) : loc;
8852 emit_side_effect_warnings (tloc, t);
8853 }
8854 }
8855 else
8856 i = tsi_last (last);
8857 last_p = tsi_stmt_ptr (i);
8858 last = *last_p;
8859 }
8860
8861 /* If the end of the list is exception related, then the list was split
8862 by a call to push_cleanup. Continue searching. */
8863 if (TREE_CODE (last) == TRY_FINALLY_EXPR
8864 || TREE_CODE (last) == TRY_CATCH_EXPR)
8865 {
8866 last_p = &TREE_OPERAND (last, 0);
8867 last = *last_p;
8868 goto continue_searching;
8869 }
8870
8871 if (last == error_mark_node)
8872 return last;
8873
8874 /* In the case that the BIND_EXPR is not necessary, return the
8875 expression out from inside it. */
8876 if (last == BIND_EXPR_BODY (body)
8877 && BIND_EXPR_VARS (body) == NULL)
8878 {
8879 /* Even if this looks constant, do not allow it in a constant
8880 expression. */
8881 last = c_wrap_maybe_const (last, true);
8882 /* Do not warn if the return value of a statement expression is
8883 unused. */
8884 TREE_NO_WARNING (last) = 1;
8885 return last;
8886 }
8887
8888 /* Extract the type of said expression. */
8889 type = TREE_TYPE (last);
8890
8891 /* If we're not returning a value at all, then the BIND_EXPR that
8892 we already have is a fine expression to return. */
8893 if (!type || VOID_TYPE_P (type))
8894 return body;
8895
8896 /* Now that we've located the expression containing the value, it seems
8897 silly to make voidify_wrapper_expr repeat the process. Create a
8898 temporary of the appropriate type and stick it in a TARGET_EXPR. */
8899 tmp = create_tmp_var_raw (type, NULL);
8900
8901 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
8902 tree_expr_nonnegative_p giving up immediately. */
8903 val = last;
8904 if (TREE_CODE (val) == NOP_EXPR
8905 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
8906 val = TREE_OPERAND (val, 0);
8907
8908 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
8909 SET_EXPR_LOCATION (*last_p, EXPR_LOCATION (last));
8910
8911 {
8912 tree t = build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
8913 SET_EXPR_LOCATION (t, loc);
8914 return t;
8915 }
8916 }
8917 \f
8918 /* Begin and end compound statements. This is as simple as pushing
8919 and popping new statement lists from the tree. */
8920
8921 tree
8922 c_begin_compound_stmt (bool do_scope)
8923 {
8924 tree stmt = push_stmt_list ();
8925 if (do_scope)
8926 push_scope ();
8927 return stmt;
8928 }
8929
8930 /* End a compound statement. STMT is the statement. LOC is the
8931 location of the compound statement-- this is usually the location
8932 of the opening brace. */
8933
8934 tree
8935 c_end_compound_stmt (location_t loc, tree stmt, bool do_scope)
8936 {
8937 tree block = NULL;
8938
8939 if (do_scope)
8940 {
8941 if (c_dialect_objc ())
8942 objc_clear_super_receiver ();
8943 block = pop_scope ();
8944 }
8945
8946 stmt = pop_stmt_list (stmt);
8947 stmt = c_build_bind_expr (loc, block, stmt);
8948
8949 /* If this compound statement is nested immediately inside a statement
8950 expression, then force a BIND_EXPR to be created. Otherwise we'll
8951 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
8952 STATEMENT_LISTs merge, and thus we can lose track of what statement
8953 was really last. */
8954 if (cur_stmt_list
8955 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
8956 && TREE_CODE (stmt) != BIND_EXPR)
8957 {
8958 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
8959 TREE_SIDE_EFFECTS (stmt) = 1;
8960 SET_EXPR_LOCATION (stmt, loc);
8961 }
8962
8963 return stmt;
8964 }
8965
8966 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
8967 when the current scope is exited. EH_ONLY is true when this is not
8968 meant to apply to normal control flow transfer. */
8969
8970 void
8971 push_cleanup (tree decl, tree cleanup, bool eh_only)
8972 {
8973 enum tree_code code;
8974 tree stmt, list;
8975 bool stmt_expr;
8976
8977 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
8978 stmt = build_stmt (DECL_SOURCE_LOCATION (decl), code, NULL, cleanup);
8979 add_stmt (stmt);
8980 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
8981 list = push_stmt_list ();
8982 TREE_OPERAND (stmt, 0) = list;
8983 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
8984 }
8985 \f
8986 /* Build a binary-operation expression without default conversions.
8987 CODE is the kind of expression to build.
8988 LOCATION is the operator's location.
8989 This function differs from `build' in several ways:
8990 the data type of the result is computed and recorded in it,
8991 warnings are generated if arg data types are invalid,
8992 special handling for addition and subtraction of pointers is known,
8993 and some optimization is done (operations on narrow ints
8994 are done in the narrower type when that gives the same result).
8995 Constant folding is also done before the result is returned.
8996
8997 Note that the operands will never have enumeral types, or function
8998 or array types, because either they will have the default conversions
8999 performed or they have both just been converted to some other type in which
9000 the arithmetic is to be done. */
9001
9002 tree
9003 build_binary_op (location_t location, enum tree_code code,
9004 tree orig_op0, tree orig_op1, int convert_p)
9005 {
9006 tree type0, type1, orig_type0, orig_type1;
9007 tree eptype;
9008 enum tree_code code0, code1;
9009 tree op0, op1;
9010 tree ret = error_mark_node;
9011 const char *invalid_op_diag;
9012 bool op0_int_operands, op1_int_operands;
9013 bool int_const, int_const_or_overflow, int_operands;
9014
9015 /* Expression code to give to the expression when it is built.
9016 Normally this is CODE, which is what the caller asked for,
9017 but in some special cases we change it. */
9018 enum tree_code resultcode = code;
9019
9020 /* Data type in which the computation is to be performed.
9021 In the simplest cases this is the common type of the arguments. */
9022 tree result_type = NULL;
9023
9024 /* When the computation is in excess precision, the type of the
9025 final EXCESS_PRECISION_EXPR. */
9026 tree real_result_type = NULL;
9027
9028 /* Nonzero means operands have already been type-converted
9029 in whatever way is necessary.
9030 Zero means they need to be converted to RESULT_TYPE. */
9031 int converted = 0;
9032
9033 /* Nonzero means create the expression with this type, rather than
9034 RESULT_TYPE. */
9035 tree build_type = 0;
9036
9037 /* Nonzero means after finally constructing the expression
9038 convert it to this type. */
9039 tree final_type = 0;
9040
9041 /* Nonzero if this is an operation like MIN or MAX which can
9042 safely be computed in short if both args are promoted shorts.
9043 Also implies COMMON.
9044 -1 indicates a bitwise operation; this makes a difference
9045 in the exact conditions for when it is safe to do the operation
9046 in a narrower mode. */
9047 int shorten = 0;
9048
9049 /* Nonzero if this is a comparison operation;
9050 if both args are promoted shorts, compare the original shorts.
9051 Also implies COMMON. */
9052 int short_compare = 0;
9053
9054 /* Nonzero if this is a right-shift operation, which can be computed on the
9055 original short and then promoted if the operand is a promoted short. */
9056 int short_shift = 0;
9057
9058 /* Nonzero means set RESULT_TYPE to the common type of the args. */
9059 int common = 0;
9060
9061 /* True means types are compatible as far as ObjC is concerned. */
9062 bool objc_ok;
9063
9064 /* True means this is an arithmetic operation that may need excess
9065 precision. */
9066 bool may_need_excess_precision;
9067
9068 if (location == UNKNOWN_LOCATION)
9069 location = input_location;
9070
9071 op0 = orig_op0;
9072 op1 = orig_op1;
9073
9074 op0_int_operands = EXPR_INT_CONST_OPERANDS (orig_op0);
9075 if (op0_int_operands)
9076 op0 = remove_c_maybe_const_expr (op0);
9077 op1_int_operands = EXPR_INT_CONST_OPERANDS (orig_op1);
9078 if (op1_int_operands)
9079 op1 = remove_c_maybe_const_expr (op1);
9080 int_operands = (op0_int_operands && op1_int_operands);
9081 if (int_operands)
9082 {
9083 int_const_or_overflow = (TREE_CODE (orig_op0) == INTEGER_CST
9084 && TREE_CODE (orig_op1) == INTEGER_CST);
9085 int_const = (int_const_or_overflow
9086 && !TREE_OVERFLOW (orig_op0)
9087 && !TREE_OVERFLOW (orig_op1));
9088 }
9089 else
9090 int_const = int_const_or_overflow = false;
9091
9092 if (convert_p)
9093 {
9094 op0 = default_conversion (op0);
9095 op1 = default_conversion (op1);
9096 }
9097
9098 orig_type0 = type0 = TREE_TYPE (op0);
9099 orig_type1 = type1 = TREE_TYPE (op1);
9100
9101 /* The expression codes of the data types of the arguments tell us
9102 whether the arguments are integers, floating, pointers, etc. */
9103 code0 = TREE_CODE (type0);
9104 code1 = TREE_CODE (type1);
9105
9106 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
9107 STRIP_TYPE_NOPS (op0);
9108 STRIP_TYPE_NOPS (op1);
9109
9110 /* If an error was already reported for one of the arguments,
9111 avoid reporting another error. */
9112
9113 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
9114 return error_mark_node;
9115
9116 if ((invalid_op_diag
9117 = targetm.invalid_binary_op (code, type0, type1)))
9118 {
9119 error_at (location, invalid_op_diag);
9120 return error_mark_node;
9121 }
9122
9123 switch (code)
9124 {
9125 case PLUS_EXPR:
9126 case MINUS_EXPR:
9127 case MULT_EXPR:
9128 case TRUNC_DIV_EXPR:
9129 case CEIL_DIV_EXPR:
9130 case FLOOR_DIV_EXPR:
9131 case ROUND_DIV_EXPR:
9132 case EXACT_DIV_EXPR:
9133 may_need_excess_precision = true;
9134 break;
9135 default:
9136 may_need_excess_precision = false;
9137 break;
9138 }
9139 if (TREE_CODE (op0) == EXCESS_PRECISION_EXPR)
9140 {
9141 op0 = TREE_OPERAND (op0, 0);
9142 type0 = TREE_TYPE (op0);
9143 }
9144 else if (may_need_excess_precision
9145 && (eptype = excess_precision_type (type0)) != NULL_TREE)
9146 {
9147 type0 = eptype;
9148 op0 = convert (eptype, op0);
9149 }
9150 if (TREE_CODE (op1) == EXCESS_PRECISION_EXPR)
9151 {
9152 op1 = TREE_OPERAND (op1, 0);
9153 type1 = TREE_TYPE (op1);
9154 }
9155 else if (may_need_excess_precision
9156 && (eptype = excess_precision_type (type1)) != NULL_TREE)
9157 {
9158 type1 = eptype;
9159 op1 = convert (eptype, op1);
9160 }
9161
9162 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE);
9163
9164 switch (code)
9165 {
9166 case PLUS_EXPR:
9167 /* Handle the pointer + int case. */
9168 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
9169 {
9170 ret = pointer_int_sum (location, PLUS_EXPR, op0, op1);
9171 goto return_build_binary_op;
9172 }
9173 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
9174 {
9175 ret = pointer_int_sum (location, PLUS_EXPR, op1, op0);
9176 goto return_build_binary_op;
9177 }
9178 else
9179 common = 1;
9180 break;
9181
9182 case MINUS_EXPR:
9183 /* Subtraction of two similar pointers.
9184 We must subtract them as integers, then divide by object size. */
9185 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
9186 && comp_target_types (location, type0, type1))
9187 {
9188 ret = pointer_diff (location, op0, op1);
9189 goto return_build_binary_op;
9190 }
9191 /* Handle pointer minus int. Just like pointer plus int. */
9192 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
9193 {
9194 ret = pointer_int_sum (location, MINUS_EXPR, op0, op1);
9195 goto return_build_binary_op;
9196 }
9197 else
9198 common = 1;
9199 break;
9200
9201 case MULT_EXPR:
9202 common = 1;
9203 break;
9204
9205 case TRUNC_DIV_EXPR:
9206 case CEIL_DIV_EXPR:
9207 case FLOOR_DIV_EXPR:
9208 case ROUND_DIV_EXPR:
9209 case EXACT_DIV_EXPR:
9210 warn_for_div_by_zero (location, op1);
9211
9212 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
9213 || code0 == FIXED_POINT_TYPE
9214 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
9215 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
9216 || code1 == FIXED_POINT_TYPE
9217 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
9218 {
9219 enum tree_code tcode0 = code0, tcode1 = code1;
9220
9221 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
9222 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
9223 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
9224 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
9225
9226 if (!((tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE)
9227 || (tcode0 == FIXED_POINT_TYPE && tcode1 == FIXED_POINT_TYPE)))
9228 resultcode = RDIV_EXPR;
9229 else
9230 /* Although it would be tempting to shorten always here, that
9231 loses on some targets, since the modulo instruction is
9232 undefined if the quotient can't be represented in the
9233 computation mode. We shorten only if unsigned or if
9234 dividing by something we know != -1. */
9235 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
9236 || (TREE_CODE (op1) == INTEGER_CST
9237 && !integer_all_onesp (op1)));
9238 common = 1;
9239 }
9240 break;
9241
9242 case BIT_AND_EXPR:
9243 case BIT_IOR_EXPR:
9244 case BIT_XOR_EXPR:
9245 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
9246 shorten = -1;
9247 /* Allow vector types which are not floating point types. */
9248 else if (code0 == VECTOR_TYPE
9249 && code1 == VECTOR_TYPE
9250 && !VECTOR_FLOAT_TYPE_P (type0)
9251 && !VECTOR_FLOAT_TYPE_P (type1))
9252 common = 1;
9253 break;
9254
9255 case TRUNC_MOD_EXPR:
9256 case FLOOR_MOD_EXPR:
9257 warn_for_div_by_zero (location, op1);
9258
9259 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
9260 && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE
9261 && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE)
9262 common = 1;
9263 else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
9264 {
9265 /* Although it would be tempting to shorten always here, that loses
9266 on some targets, since the modulo instruction is undefined if the
9267 quotient can't be represented in the computation mode. We shorten
9268 only if unsigned or if dividing by something we know != -1. */
9269 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
9270 || (TREE_CODE (op1) == INTEGER_CST
9271 && !integer_all_onesp (op1)));
9272 common = 1;
9273 }
9274 break;
9275
9276 case TRUTH_ANDIF_EXPR:
9277 case TRUTH_ORIF_EXPR:
9278 case TRUTH_AND_EXPR:
9279 case TRUTH_OR_EXPR:
9280 case TRUTH_XOR_EXPR:
9281 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
9282 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
9283 || code0 == FIXED_POINT_TYPE)
9284 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
9285 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
9286 || code1 == FIXED_POINT_TYPE))
9287 {
9288 /* Result of these operations is always an int,
9289 but that does not mean the operands should be
9290 converted to ints! */
9291 result_type = integer_type_node;
9292 op0 = c_common_truthvalue_conversion (location, op0);
9293 op1 = c_common_truthvalue_conversion (location, op1);
9294 converted = 1;
9295 }
9296 if (code == TRUTH_ANDIF_EXPR)
9297 {
9298 int_const_or_overflow = (int_operands
9299 && TREE_CODE (orig_op0) == INTEGER_CST
9300 && (op0 == truthvalue_false_node
9301 || TREE_CODE (orig_op1) == INTEGER_CST));
9302 int_const = (int_const_or_overflow
9303 && !TREE_OVERFLOW (orig_op0)
9304 && (op0 == truthvalue_false_node
9305 || !TREE_OVERFLOW (orig_op1)));
9306 }
9307 else if (code == TRUTH_ORIF_EXPR)
9308 {
9309 int_const_or_overflow = (int_operands
9310 && TREE_CODE (orig_op0) == INTEGER_CST
9311 && (op0 == truthvalue_true_node
9312 || TREE_CODE (orig_op1) == INTEGER_CST));
9313 int_const = (int_const_or_overflow
9314 && !TREE_OVERFLOW (orig_op0)
9315 && (op0 == truthvalue_true_node
9316 || !TREE_OVERFLOW (orig_op1)));
9317 }
9318 break;
9319
9320 /* Shift operations: result has same type as first operand;
9321 always convert second operand to int.
9322 Also set SHORT_SHIFT if shifting rightward. */
9323
9324 case RSHIFT_EXPR:
9325 if ((code0 == INTEGER_TYPE || code0 == FIXED_POINT_TYPE)
9326 && code1 == INTEGER_TYPE)
9327 {
9328 if (TREE_CODE (op1) == INTEGER_CST)
9329 {
9330 if (tree_int_cst_sgn (op1) < 0)
9331 {
9332 int_const = false;
9333 if (c_inhibit_evaluation_warnings == 0)
9334 warning (0, "right shift count is negative");
9335 }
9336 else
9337 {
9338 if (!integer_zerop (op1))
9339 short_shift = 1;
9340
9341 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
9342 {
9343 int_const = false;
9344 if (c_inhibit_evaluation_warnings == 0)
9345 warning (0, "right shift count >= width of type");
9346 }
9347 }
9348 }
9349
9350 /* Use the type of the value to be shifted. */
9351 result_type = type0;
9352 /* Convert the shift-count to an integer, regardless of size
9353 of value being shifted. */
9354 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
9355 op1 = convert (integer_type_node, op1);
9356 /* Avoid converting op1 to result_type later. */
9357 converted = 1;
9358 }
9359 break;
9360
9361 case LSHIFT_EXPR:
9362 if ((code0 == INTEGER_TYPE || code0 == FIXED_POINT_TYPE)
9363 && code1 == INTEGER_TYPE)
9364 {
9365 if (TREE_CODE (op1) == INTEGER_CST)
9366 {
9367 if (tree_int_cst_sgn (op1) < 0)
9368 {
9369 int_const = false;
9370 if (c_inhibit_evaluation_warnings == 0)
9371 warning (0, "left shift count is negative");
9372 }
9373
9374 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
9375 {
9376 int_const = false;
9377 if (c_inhibit_evaluation_warnings == 0)
9378 warning (0, "left shift count >= width of type");
9379 }
9380 }
9381
9382 /* Use the type of the value to be shifted. */
9383 result_type = type0;
9384 /* Convert the shift-count to an integer, regardless of size
9385 of value being shifted. */
9386 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
9387 op1 = convert (integer_type_node, op1);
9388 /* Avoid converting op1 to result_type later. */
9389 converted = 1;
9390 }
9391 break;
9392
9393 case EQ_EXPR:
9394 case NE_EXPR:
9395 if (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1))
9396 warning_at (location,
9397 OPT_Wfloat_equal,
9398 "comparing floating point with == or != is unsafe");
9399 /* Result of comparison is always int,
9400 but don't convert the args to int! */
9401 build_type = integer_type_node;
9402 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
9403 || code0 == FIXED_POINT_TYPE || code0 == COMPLEX_TYPE)
9404 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
9405 || code1 == FIXED_POINT_TYPE || code1 == COMPLEX_TYPE))
9406 short_compare = 1;
9407 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
9408 {
9409 tree tt0 = TREE_TYPE (type0);
9410 tree tt1 = TREE_TYPE (type1);
9411 addr_space_t as0 = TYPE_ADDR_SPACE (tt0);
9412 addr_space_t as1 = TYPE_ADDR_SPACE (tt1);
9413 addr_space_t as_common = ADDR_SPACE_GENERIC;
9414
9415 /* Anything compares with void *. void * compares with anything.
9416 Otherwise, the targets must be compatible
9417 and both must be object or both incomplete. */
9418 if (comp_target_types (location, type0, type1))
9419 result_type = common_pointer_type (type0, type1);
9420 else if (null_pointer_constant_p (orig_op0))
9421 result_type = type1;
9422 else if (null_pointer_constant_p (orig_op1))
9423 result_type = type0;
9424 else if (!addr_space_superset (as0, as1, &as_common))
9425 {
9426 error_at (location, "comparison of pointers to "
9427 "disjoint address spaces");
9428 return error_mark_node;
9429 }
9430 else if (VOID_TYPE_P (tt0))
9431 {
9432 if (pedantic && TREE_CODE (tt1) == FUNCTION_TYPE)
9433 pedwarn (location, OPT_pedantic, "ISO C forbids "
9434 "comparison of %<void *%> with function pointer");
9435 }
9436 else if (VOID_TYPE_P (tt1))
9437 {
9438 if (pedantic && TREE_CODE (tt0) == FUNCTION_TYPE)
9439 pedwarn (location, OPT_pedantic, "ISO C forbids "
9440 "comparison of %<void *%> with function pointer");
9441 }
9442 else
9443 /* Avoid warning about the volatile ObjC EH puts on decls. */
9444 if (!objc_ok)
9445 pedwarn (location, 0,
9446 "comparison of distinct pointer types lacks a cast");
9447
9448 if (result_type == NULL_TREE)
9449 {
9450 int qual = ENCODE_QUAL_ADDR_SPACE (as_common);
9451 result_type = build_pointer_type
9452 (build_qualified_type (void_type_node, qual));
9453 }
9454 }
9455 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
9456 {
9457 if (TREE_CODE (op0) == ADDR_EXPR
9458 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
9459 warning_at (location,
9460 OPT_Waddress, "the address of %qD will never be NULL",
9461 TREE_OPERAND (op0, 0));
9462 result_type = type0;
9463 }
9464 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
9465 {
9466 if (TREE_CODE (op1) == ADDR_EXPR
9467 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
9468 warning_at (location,
9469 OPT_Waddress, "the address of %qD will never be NULL",
9470 TREE_OPERAND (op1, 0));
9471 result_type = type1;
9472 }
9473 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
9474 {
9475 result_type = type0;
9476 pedwarn (location, 0, "comparison between pointer and integer");
9477 }
9478 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
9479 {
9480 result_type = type1;
9481 pedwarn (location, 0, "comparison between pointer and integer");
9482 }
9483 break;
9484
9485 case LE_EXPR:
9486 case GE_EXPR:
9487 case LT_EXPR:
9488 case GT_EXPR:
9489 build_type = integer_type_node;
9490 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
9491 || code0 == FIXED_POINT_TYPE)
9492 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
9493 || code1 == FIXED_POINT_TYPE))
9494 short_compare = 1;
9495 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
9496 {
9497 addr_space_t as0 = TYPE_ADDR_SPACE (TREE_TYPE (type0));
9498 addr_space_t as1 = TYPE_ADDR_SPACE (TREE_TYPE (type1));
9499 addr_space_t as_common;
9500
9501 if (comp_target_types (location, type0, type1))
9502 {
9503 result_type = common_pointer_type (type0, type1);
9504 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
9505 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
9506 pedwarn (location, 0,
9507 "comparison of complete and incomplete pointers");
9508 else if (TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
9509 pedwarn (location, OPT_pedantic, "ISO C forbids "
9510 "ordered comparisons of pointers to functions");
9511 }
9512 else if (!addr_space_superset (as0, as1, &as_common))
9513 {
9514 error_at (location, "comparison of pointers to "
9515 "disjoint address spaces");
9516 return error_mark_node;
9517 }
9518 else
9519 {
9520 int qual = ENCODE_QUAL_ADDR_SPACE (as_common);
9521 result_type = build_pointer_type
9522 (build_qualified_type (void_type_node, qual));
9523 pedwarn (location, 0,
9524 "comparison of distinct pointer types lacks a cast");
9525 }
9526 }
9527 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
9528 {
9529 result_type = type0;
9530 if (pedantic)
9531 pedwarn (location, OPT_pedantic,
9532 "ordered comparison of pointer with integer zero");
9533 else if (extra_warnings)
9534 warning_at (location, OPT_Wextra,
9535 "ordered comparison of pointer with integer zero");
9536 }
9537 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
9538 {
9539 result_type = type1;
9540 pedwarn (location, OPT_pedantic,
9541 "ordered comparison of pointer with integer zero");
9542 }
9543 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
9544 {
9545 result_type = type0;
9546 pedwarn (location, 0, "comparison between pointer and integer");
9547 }
9548 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
9549 {
9550 result_type = type1;
9551 pedwarn (location, 0, "comparison between pointer and integer");
9552 }
9553 break;
9554
9555 default:
9556 gcc_unreachable ();
9557 }
9558
9559 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
9560 return error_mark_node;
9561
9562 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
9563 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
9564 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
9565 TREE_TYPE (type1))))
9566 {
9567 binary_op_error (location, code, type0, type1);
9568 return error_mark_node;
9569 }
9570
9571 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
9572 || code0 == FIXED_POINT_TYPE || code0 == VECTOR_TYPE)
9573 &&
9574 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
9575 || code1 == FIXED_POINT_TYPE || code1 == VECTOR_TYPE))
9576 {
9577 bool first_complex = (code0 == COMPLEX_TYPE);
9578 bool second_complex = (code1 == COMPLEX_TYPE);
9579 int none_complex = (!first_complex && !second_complex);
9580
9581 if (shorten || common || short_compare)
9582 {
9583 result_type = c_common_type (type0, type1);
9584 if (result_type == error_mark_node)
9585 return error_mark_node;
9586 }
9587
9588 if (first_complex != second_complex
9589 && (code == PLUS_EXPR
9590 || code == MINUS_EXPR
9591 || code == MULT_EXPR
9592 || (code == TRUNC_DIV_EXPR && first_complex))
9593 && TREE_CODE (TREE_TYPE (result_type)) == REAL_TYPE
9594 && flag_signed_zeros)
9595 {
9596 /* An operation on mixed real/complex operands must be
9597 handled specially, but the language-independent code can
9598 more easily optimize the plain complex arithmetic if
9599 -fno-signed-zeros. */
9600 tree real_type = TREE_TYPE (result_type);
9601 tree real, imag;
9602 if (type0 != orig_type0 || type1 != orig_type1)
9603 {
9604 gcc_assert (may_need_excess_precision && common);
9605 real_result_type = c_common_type (orig_type0, orig_type1);
9606 }
9607 if (first_complex)
9608 {
9609 if (TREE_TYPE (op0) != result_type)
9610 op0 = convert_and_check (result_type, op0);
9611 if (TREE_TYPE (op1) != real_type)
9612 op1 = convert_and_check (real_type, op1);
9613 }
9614 else
9615 {
9616 if (TREE_TYPE (op0) != real_type)
9617 op0 = convert_and_check (real_type, op0);
9618 if (TREE_TYPE (op1) != result_type)
9619 op1 = convert_and_check (result_type, op1);
9620 }
9621 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
9622 return error_mark_node;
9623 if (first_complex)
9624 {
9625 op0 = c_save_expr (op0);
9626 real = build_unary_op (EXPR_LOCATION (orig_op0), REALPART_EXPR,
9627 op0, 1);
9628 imag = build_unary_op (EXPR_LOCATION (orig_op0), IMAGPART_EXPR,
9629 op0, 1);
9630 switch (code)
9631 {
9632 case MULT_EXPR:
9633 case TRUNC_DIV_EXPR:
9634 imag = build2 (resultcode, real_type, imag, op1);
9635 /* Fall through. */
9636 case PLUS_EXPR:
9637 case MINUS_EXPR:
9638 real = build2 (resultcode, real_type, real, op1);
9639 break;
9640 default:
9641 gcc_unreachable();
9642 }
9643 }
9644 else
9645 {
9646 op1 = c_save_expr (op1);
9647 real = build_unary_op (EXPR_LOCATION (orig_op1), REALPART_EXPR,
9648 op1, 1);
9649 imag = build_unary_op (EXPR_LOCATION (orig_op1), IMAGPART_EXPR,
9650 op1, 1);
9651 switch (code)
9652 {
9653 case MULT_EXPR:
9654 imag = build2 (resultcode, real_type, op0, imag);
9655 /* Fall through. */
9656 case PLUS_EXPR:
9657 real = build2 (resultcode, real_type, op0, real);
9658 break;
9659 case MINUS_EXPR:
9660 real = build2 (resultcode, real_type, op0, real);
9661 imag = build1 (NEGATE_EXPR, real_type, imag);
9662 break;
9663 default:
9664 gcc_unreachable();
9665 }
9666 }
9667 ret = build2 (COMPLEX_EXPR, result_type, real, imag);
9668 goto return_build_binary_op;
9669 }
9670
9671 /* For certain operations (which identify themselves by shorten != 0)
9672 if both args were extended from the same smaller type,
9673 do the arithmetic in that type and then extend.
9674
9675 shorten !=0 and !=1 indicates a bitwise operation.
9676 For them, this optimization is safe only if
9677 both args are zero-extended or both are sign-extended.
9678 Otherwise, we might change the result.
9679 Eg, (short)-1 | (unsigned short)-1 is (int)-1
9680 but calculated in (unsigned short) it would be (unsigned short)-1. */
9681
9682 if (shorten && none_complex)
9683 {
9684 final_type = result_type;
9685 result_type = shorten_binary_op (result_type, op0, op1,
9686 shorten == -1);
9687 }
9688
9689 /* Shifts can be shortened if shifting right. */
9690
9691 if (short_shift)
9692 {
9693 int unsigned_arg;
9694 tree arg0 = get_narrower (op0, &unsigned_arg);
9695
9696 final_type = result_type;
9697
9698 if (arg0 == op0 && final_type == TREE_TYPE (op0))
9699 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
9700
9701 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
9702 && tree_int_cst_sgn (op1) > 0
9703 /* We can shorten only if the shift count is less than the
9704 number of bits in the smaller type size. */
9705 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
9706 /* We cannot drop an unsigned shift after sign-extension. */
9707 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
9708 {
9709 /* Do an unsigned shift if the operand was zero-extended. */
9710 result_type
9711 = c_common_signed_or_unsigned_type (unsigned_arg,
9712 TREE_TYPE (arg0));
9713 /* Convert value-to-be-shifted to that type. */
9714 if (TREE_TYPE (op0) != result_type)
9715 op0 = convert (result_type, op0);
9716 converted = 1;
9717 }
9718 }
9719
9720 /* Comparison operations are shortened too but differently.
9721 They identify themselves by setting short_compare = 1. */
9722
9723 if (short_compare)
9724 {
9725 /* Don't write &op0, etc., because that would prevent op0
9726 from being kept in a register.
9727 Instead, make copies of the our local variables and
9728 pass the copies by reference, then copy them back afterward. */
9729 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
9730 enum tree_code xresultcode = resultcode;
9731 tree val
9732 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
9733
9734 if (val != 0)
9735 {
9736 ret = val;
9737 goto return_build_binary_op;
9738 }
9739
9740 op0 = xop0, op1 = xop1;
9741 converted = 1;
9742 resultcode = xresultcode;
9743
9744 if (c_inhibit_evaluation_warnings == 0)
9745 {
9746 bool op0_maybe_const = true;
9747 bool op1_maybe_const = true;
9748 tree orig_op0_folded, orig_op1_folded;
9749
9750 if (in_late_binary_op)
9751 {
9752 orig_op0_folded = orig_op0;
9753 orig_op1_folded = orig_op1;
9754 }
9755 else
9756 {
9757 /* Fold for the sake of possible warnings, as in
9758 build_conditional_expr. This requires the
9759 "original" values to be folded, not just op0 and
9760 op1. */
9761 c_inhibit_evaluation_warnings++;
9762 op0 = c_fully_fold (op0, require_constant_value,
9763 &op0_maybe_const);
9764 op1 = c_fully_fold (op1, require_constant_value,
9765 &op1_maybe_const);
9766 c_inhibit_evaluation_warnings--;
9767 orig_op0_folded = c_fully_fold (orig_op0,
9768 require_constant_value,
9769 NULL);
9770 orig_op1_folded = c_fully_fold (orig_op1,
9771 require_constant_value,
9772 NULL);
9773 }
9774
9775 if (warn_sign_compare)
9776 warn_for_sign_compare (location, orig_op0_folded,
9777 orig_op1_folded, op0, op1,
9778 result_type, resultcode);
9779 if (!in_late_binary_op)
9780 {
9781 if (!op0_maybe_const || TREE_CODE (op0) != INTEGER_CST)
9782 op0 = c_wrap_maybe_const (op0, !op0_maybe_const);
9783 if (!op1_maybe_const || TREE_CODE (op1) != INTEGER_CST)
9784 op1 = c_wrap_maybe_const (op1, !op1_maybe_const);
9785 }
9786 }
9787 }
9788 }
9789
9790 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
9791 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
9792 Then the expression will be built.
9793 It will be given type FINAL_TYPE if that is nonzero;
9794 otherwise, it will be given type RESULT_TYPE. */
9795
9796 if (!result_type)
9797 {
9798 binary_op_error (location, code, TREE_TYPE (op0), TREE_TYPE (op1));
9799 return error_mark_node;
9800 }
9801
9802 if (!converted)
9803 {
9804 if (TREE_TYPE (op0) != result_type)
9805 op0 = convert_and_check (result_type, op0);
9806 if (TREE_TYPE (op1) != result_type)
9807 op1 = convert_and_check (result_type, op1);
9808
9809 /* This can happen if one operand has a vector type, and the other
9810 has a different type. */
9811 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
9812 return error_mark_node;
9813 }
9814
9815 if (build_type == NULL_TREE)
9816 {
9817 build_type = result_type;
9818 if (type0 != orig_type0 || type1 != orig_type1)
9819 {
9820 gcc_assert (may_need_excess_precision && common);
9821 real_result_type = c_common_type (orig_type0, orig_type1);
9822 }
9823 }
9824
9825 /* Treat expressions in initializers specially as they can't trap. */
9826 if (int_const_or_overflow)
9827 ret = (require_constant_value
9828 ? fold_build2_initializer_loc (location, resultcode, build_type,
9829 op0, op1)
9830 : fold_build2_loc (location, resultcode, build_type, op0, op1));
9831 else
9832 ret = build2 (resultcode, build_type, op0, op1);
9833 if (final_type != 0)
9834 ret = convert (final_type, ret);
9835
9836 return_build_binary_op:
9837 gcc_assert (ret != error_mark_node);
9838 if (TREE_CODE (ret) == INTEGER_CST && !TREE_OVERFLOW (ret) && !int_const)
9839 ret = (int_operands
9840 ? note_integer_operands (ret)
9841 : build1 (NOP_EXPR, TREE_TYPE (ret), ret));
9842 else if (TREE_CODE (ret) != INTEGER_CST && int_operands
9843 && !in_late_binary_op)
9844 ret = note_integer_operands (ret);
9845 if (real_result_type)
9846 ret = build1 (EXCESS_PRECISION_EXPR, real_result_type, ret);
9847 protected_set_expr_location (ret, location);
9848 return ret;
9849 }
9850
9851
9852 /* Convert EXPR to be a truth-value, validating its type for this
9853 purpose. LOCATION is the source location for the expression. */
9854
9855 tree
9856 c_objc_common_truthvalue_conversion (location_t location, tree expr)
9857 {
9858 bool int_const, int_operands;
9859
9860 switch (TREE_CODE (TREE_TYPE (expr)))
9861 {
9862 case ARRAY_TYPE:
9863 error_at (location, "used array that cannot be converted to pointer where scalar is required");
9864 return error_mark_node;
9865
9866 case RECORD_TYPE:
9867 error_at (location, "used struct type value where scalar is required");
9868 return error_mark_node;
9869
9870 case UNION_TYPE:
9871 error_at (location, "used union type value where scalar is required");
9872 return error_mark_node;
9873
9874 case FUNCTION_TYPE:
9875 gcc_unreachable ();
9876
9877 default:
9878 break;
9879 }
9880
9881 int_const = (TREE_CODE (expr) == INTEGER_CST && !TREE_OVERFLOW (expr));
9882 int_operands = EXPR_INT_CONST_OPERANDS (expr);
9883 if (int_operands)
9884 expr = remove_c_maybe_const_expr (expr);
9885
9886 /* ??? Should we also give an error for void and vectors rather than
9887 leaving those to give errors later? */
9888 expr = c_common_truthvalue_conversion (location, expr);
9889
9890 if (TREE_CODE (expr) == INTEGER_CST && int_operands && !int_const)
9891 {
9892 if (TREE_OVERFLOW (expr))
9893 return expr;
9894 else
9895 return note_integer_operands (expr);
9896 }
9897 if (TREE_CODE (expr) == INTEGER_CST && !int_const)
9898 return build1 (NOP_EXPR, TREE_TYPE (expr), expr);
9899 return expr;
9900 }
9901 \f
9902
9903 /* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as
9904 required. */
9905
9906 tree
9907 c_expr_to_decl (tree expr, bool *tc ATTRIBUTE_UNUSED, bool *se)
9908 {
9909 if (TREE_CODE (expr) == COMPOUND_LITERAL_EXPR)
9910 {
9911 tree decl = COMPOUND_LITERAL_EXPR_DECL (expr);
9912 /* Executing a compound literal inside a function reinitializes
9913 it. */
9914 if (!TREE_STATIC (decl))
9915 *se = true;
9916 return decl;
9917 }
9918 else
9919 return expr;
9920 }
9921 \f
9922 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
9923
9924 tree
9925 c_begin_omp_parallel (void)
9926 {
9927 tree block;
9928
9929 keep_next_level ();
9930 block = c_begin_compound_stmt (true);
9931
9932 return block;
9933 }
9934
9935 /* Generate OMP_PARALLEL, with CLAUSES and BLOCK as its compound
9936 statement. LOC is the location of the OMP_PARALLEL. */
9937
9938 tree
9939 c_finish_omp_parallel (location_t loc, tree clauses, tree block)
9940 {
9941 tree stmt;
9942
9943 block = c_end_compound_stmt (loc, block, true);
9944
9945 stmt = make_node (OMP_PARALLEL);
9946 TREE_TYPE (stmt) = void_type_node;
9947 OMP_PARALLEL_CLAUSES (stmt) = clauses;
9948 OMP_PARALLEL_BODY (stmt) = block;
9949 SET_EXPR_LOCATION (stmt, loc);
9950
9951 return add_stmt (stmt);
9952 }
9953
9954 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
9955
9956 tree
9957 c_begin_omp_task (void)
9958 {
9959 tree block;
9960
9961 keep_next_level ();
9962 block = c_begin_compound_stmt (true);
9963
9964 return block;
9965 }
9966
9967 /* Generate OMP_TASK, with CLAUSES and BLOCK as its compound
9968 statement. LOC is the location of the #pragma. */
9969
9970 tree
9971 c_finish_omp_task (location_t loc, tree clauses, tree block)
9972 {
9973 tree stmt;
9974
9975 block = c_end_compound_stmt (loc, block, true);
9976
9977 stmt = make_node (OMP_TASK);
9978 TREE_TYPE (stmt) = void_type_node;
9979 OMP_TASK_CLAUSES (stmt) = clauses;
9980 OMP_TASK_BODY (stmt) = block;
9981 SET_EXPR_LOCATION (stmt, loc);
9982
9983 return add_stmt (stmt);
9984 }
9985
9986 /* For all elements of CLAUSES, validate them vs OpenMP constraints.
9987 Remove any elements from the list that are invalid. */
9988
9989 tree
9990 c_finish_omp_clauses (tree clauses)
9991 {
9992 bitmap_head generic_head, firstprivate_head, lastprivate_head;
9993 tree c, t, *pc = &clauses;
9994 const char *name;
9995
9996 bitmap_obstack_initialize (NULL);
9997 bitmap_initialize (&generic_head, &bitmap_default_obstack);
9998 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack);
9999 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack);
10000
10001 for (pc = &clauses, c = clauses; c ; c = *pc)
10002 {
10003 bool remove = false;
10004 bool need_complete = false;
10005 bool need_implicitly_determined = false;
10006
10007 switch (OMP_CLAUSE_CODE (c))
10008 {
10009 case OMP_CLAUSE_SHARED:
10010 name = "shared";
10011 need_implicitly_determined = true;
10012 goto check_dup_generic;
10013
10014 case OMP_CLAUSE_PRIVATE:
10015 name = "private";
10016 need_complete = true;
10017 need_implicitly_determined = true;
10018 goto check_dup_generic;
10019
10020 case OMP_CLAUSE_REDUCTION:
10021 name = "reduction";
10022 need_implicitly_determined = true;
10023 t = OMP_CLAUSE_DECL (c);
10024 if (AGGREGATE_TYPE_P (TREE_TYPE (t))
10025 || POINTER_TYPE_P (TREE_TYPE (t)))
10026 {
10027 error_at (OMP_CLAUSE_LOCATION (c),
10028 "%qE has invalid type for %<reduction%>", t);
10029 remove = true;
10030 }
10031 else if (FLOAT_TYPE_P (TREE_TYPE (t)))
10032 {
10033 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c);
10034 const char *r_name = NULL;
10035
10036 switch (r_code)
10037 {
10038 case PLUS_EXPR:
10039 case MULT_EXPR:
10040 case MINUS_EXPR:
10041 break;
10042 case BIT_AND_EXPR:
10043 r_name = "&";
10044 break;
10045 case BIT_XOR_EXPR:
10046 r_name = "^";
10047 break;
10048 case BIT_IOR_EXPR:
10049 r_name = "|";
10050 break;
10051 case TRUTH_ANDIF_EXPR:
10052 r_name = "&&";
10053 break;
10054 case TRUTH_ORIF_EXPR:
10055 r_name = "||";
10056 break;
10057 default:
10058 gcc_unreachable ();
10059 }
10060 if (r_name)
10061 {
10062 error_at (OMP_CLAUSE_LOCATION (c),
10063 "%qE has invalid type for %<reduction(%s)%>",
10064 t, r_name);
10065 remove = true;
10066 }
10067 }
10068 goto check_dup_generic;
10069
10070 case OMP_CLAUSE_COPYPRIVATE:
10071 name = "copyprivate";
10072 goto check_dup_generic;
10073
10074 case OMP_CLAUSE_COPYIN:
10075 name = "copyin";
10076 t = OMP_CLAUSE_DECL (c);
10077 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t))
10078 {
10079 error_at (OMP_CLAUSE_LOCATION (c),
10080 "%qE must be %<threadprivate%> for %<copyin%>", t);
10081 remove = true;
10082 }
10083 goto check_dup_generic;
10084
10085 check_dup_generic:
10086 t = OMP_CLAUSE_DECL (c);
10087 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
10088 {
10089 error_at (OMP_CLAUSE_LOCATION (c),
10090 "%qE is not a variable in clause %qs", t, name);
10091 remove = true;
10092 }
10093 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
10094 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))
10095 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
10096 {
10097 error_at (OMP_CLAUSE_LOCATION (c),
10098 "%qE appears more than once in data clauses", t);
10099 remove = true;
10100 }
10101 else
10102 bitmap_set_bit (&generic_head, DECL_UID (t));
10103 break;
10104
10105 case OMP_CLAUSE_FIRSTPRIVATE:
10106 name = "firstprivate";
10107 t = OMP_CLAUSE_DECL (c);
10108 need_complete = true;
10109 need_implicitly_determined = true;
10110 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
10111 {
10112 error_at (OMP_CLAUSE_LOCATION (c),
10113 "%qE is not a variable in clause %<firstprivate%>", t);
10114 remove = true;
10115 }
10116 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
10117 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)))
10118 {
10119 error_at (OMP_CLAUSE_LOCATION (c),
10120 "%qE appears more than once in data clauses", t);
10121 remove = true;
10122 }
10123 else
10124 bitmap_set_bit (&firstprivate_head, DECL_UID (t));
10125 break;
10126
10127 case OMP_CLAUSE_LASTPRIVATE:
10128 name = "lastprivate";
10129 t = OMP_CLAUSE_DECL (c);
10130 need_complete = true;
10131 need_implicitly_determined = true;
10132 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
10133 {
10134 error_at (OMP_CLAUSE_LOCATION (c),
10135 "%qE is not a variable in clause %<lastprivate%>", t);
10136 remove = true;
10137 }
10138 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
10139 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
10140 {
10141 error_at (OMP_CLAUSE_LOCATION (c),
10142 "%qE appears more than once in data clauses", t);
10143 remove = true;
10144 }
10145 else
10146 bitmap_set_bit (&lastprivate_head, DECL_UID (t));
10147 break;
10148
10149 case OMP_CLAUSE_IF:
10150 case OMP_CLAUSE_NUM_THREADS:
10151 case OMP_CLAUSE_SCHEDULE:
10152 case OMP_CLAUSE_NOWAIT:
10153 case OMP_CLAUSE_ORDERED:
10154 case OMP_CLAUSE_DEFAULT:
10155 case OMP_CLAUSE_UNTIED:
10156 case OMP_CLAUSE_COLLAPSE:
10157 pc = &OMP_CLAUSE_CHAIN (c);
10158 continue;
10159
10160 default:
10161 gcc_unreachable ();
10162 }
10163
10164 if (!remove)
10165 {
10166 t = OMP_CLAUSE_DECL (c);
10167
10168 if (need_complete)
10169 {
10170 t = require_complete_type (t);
10171 if (t == error_mark_node)
10172 remove = true;
10173 }
10174
10175 if (need_implicitly_determined)
10176 {
10177 const char *share_name = NULL;
10178
10179 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t))
10180 share_name = "threadprivate";
10181 else switch (c_omp_predetermined_sharing (t))
10182 {
10183 case OMP_CLAUSE_DEFAULT_UNSPECIFIED:
10184 break;
10185 case OMP_CLAUSE_DEFAULT_SHARED:
10186 share_name = "shared";
10187 break;
10188 case OMP_CLAUSE_DEFAULT_PRIVATE:
10189 share_name = "private";
10190 break;
10191 default:
10192 gcc_unreachable ();
10193 }
10194 if (share_name)
10195 {
10196 error_at (OMP_CLAUSE_LOCATION (c),
10197 "%qE is predetermined %qs for %qs",
10198 t, share_name, name);
10199 remove = true;
10200 }
10201 }
10202 }
10203
10204 if (remove)
10205 *pc = OMP_CLAUSE_CHAIN (c);
10206 else
10207 pc = &OMP_CLAUSE_CHAIN (c);
10208 }
10209
10210 bitmap_obstack_release (NULL);
10211 return clauses;
10212 }
10213
10214 /* Make a variant type in the proper way for C/C++, propagating qualifiers
10215 down to the element type of an array. */
10216
10217 tree
10218 c_build_qualified_type (tree type, int type_quals)
10219 {
10220 if (type == error_mark_node)
10221 return type;
10222
10223 if (TREE_CODE (type) == ARRAY_TYPE)
10224 {
10225 tree t;
10226 tree element_type = c_build_qualified_type (TREE_TYPE (type),
10227 type_quals);
10228
10229 /* See if we already have an identically qualified type. */
10230 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
10231 {
10232 if (TYPE_QUALS (strip_array_types (t)) == type_quals
10233 && TYPE_NAME (t) == TYPE_NAME (type)
10234 && TYPE_CONTEXT (t) == TYPE_CONTEXT (type)
10235 && attribute_list_equal (TYPE_ATTRIBUTES (t),
10236 TYPE_ATTRIBUTES (type)))
10237 break;
10238 }
10239 if (!t)
10240 {
10241 tree domain = TYPE_DOMAIN (type);
10242
10243 t = build_variant_type_copy (type);
10244 TREE_TYPE (t) = element_type;
10245
10246 if (TYPE_STRUCTURAL_EQUALITY_P (element_type)
10247 || (domain && TYPE_STRUCTURAL_EQUALITY_P (domain)))
10248 SET_TYPE_STRUCTURAL_EQUALITY (t);
10249 else if (TYPE_CANONICAL (element_type) != element_type
10250 || (domain && TYPE_CANONICAL (domain) != domain))
10251 {
10252 tree unqualified_canon
10253 = build_array_type (TYPE_CANONICAL (element_type),
10254 domain? TYPE_CANONICAL (domain)
10255 : NULL_TREE);
10256 TYPE_CANONICAL (t)
10257 = c_build_qualified_type (unqualified_canon, type_quals);
10258 }
10259 else
10260 TYPE_CANONICAL (t) = t;
10261 }
10262 return t;
10263 }
10264
10265 /* A restrict-qualified pointer type must be a pointer to object or
10266 incomplete type. Note that the use of POINTER_TYPE_P also allows
10267 REFERENCE_TYPEs, which is appropriate for C++. */
10268 if ((type_quals & TYPE_QUAL_RESTRICT)
10269 && (!POINTER_TYPE_P (type)
10270 || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (type))))
10271 {
10272 error ("invalid use of %<restrict%>");
10273 type_quals &= ~TYPE_QUAL_RESTRICT;
10274 }
10275
10276 return build_qualified_type (type, type_quals);
10277 }
10278
10279 /* Build a VA_ARG_EXPR for the C parser. */
10280
10281 tree
10282 c_build_va_arg (location_t loc, tree expr, tree type)
10283 {
10284 if (warn_cxx_compat && TREE_CODE (type) == ENUMERAL_TYPE)
10285 warning_at (loc, OPT_Wc___compat,
10286 "C++ requires promoted type, not enum type, in %<va_arg%>");
10287 return build_va_arg (loc, expr, type);
10288 }