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re PR tree-optimization/43833 (false warning: array subscript is above array bounds...
[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, 2010
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 struct obstack *);
102 static void output_pending_init_elements (int, struct obstack *);
103 static int set_designator (int, struct obstack *);
104 static void push_range_stack (tree, struct obstack *);
105 static void add_pending_init (tree, tree, tree, bool, struct obstack *);
106 static void set_nonincremental_init (struct obstack *);
107 static void set_nonincremental_init_from_string (tree, struct obstack *);
108 static tree find_init_member (tree, struct obstack *);
109 static void readonly_error (tree, enum lvalue_use);
110 static void readonly_warning (tree, enum lvalue_use);
111 static int lvalue_or_else (const_tree, enum lvalue_use);
112 static void record_maybe_used_decl (tree);
113 static int comptypes_internal (const_tree, const_tree, bool *);
114 \f
115 /* Return true if EXP is a null pointer constant, false otherwise. */
116
117 static bool
118 null_pointer_constant_p (const_tree expr)
119 {
120 /* This should really operate on c_expr structures, but they aren't
121 yet available everywhere required. */
122 tree type = TREE_TYPE (expr);
123 return (TREE_CODE (expr) == INTEGER_CST
124 && !TREE_OVERFLOW (expr)
125 && integer_zerop (expr)
126 && (INTEGRAL_TYPE_P (type)
127 || (TREE_CODE (type) == POINTER_TYPE
128 && VOID_TYPE_P (TREE_TYPE (type))
129 && TYPE_QUALS (TREE_TYPE (type)) == TYPE_UNQUALIFIED)));
130 }
131
132 /* EXPR may appear in an unevaluated part of an integer constant
133 expression, but not in an evaluated part. Wrap it in a
134 C_MAYBE_CONST_EXPR, or mark it with TREE_OVERFLOW if it is just an
135 INTEGER_CST and we cannot create a C_MAYBE_CONST_EXPR. */
136
137 static tree
138 note_integer_operands (tree expr)
139 {
140 tree ret;
141 if (TREE_CODE (expr) == INTEGER_CST && in_late_binary_op)
142 {
143 ret = copy_node (expr);
144 TREE_OVERFLOW (ret) = 1;
145 }
146 else
147 {
148 ret = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (expr), NULL_TREE, expr);
149 C_MAYBE_CONST_EXPR_INT_OPERANDS (ret) = 1;
150 }
151 return ret;
152 }
153
154 /* Having checked whether EXPR may appear in an unevaluated part of an
155 integer constant expression and found that it may, remove any
156 C_MAYBE_CONST_EXPR noting this fact and return the resulting
157 expression. */
158
159 static inline tree
160 remove_c_maybe_const_expr (tree expr)
161 {
162 if (TREE_CODE (expr) == C_MAYBE_CONST_EXPR)
163 return C_MAYBE_CONST_EXPR_EXPR (expr);
164 else
165 return expr;
166 }
167
168 \f/* This is a cache to hold if two types are compatible or not. */
169
170 struct tagged_tu_seen_cache {
171 const struct tagged_tu_seen_cache * next;
172 const_tree t1;
173 const_tree t2;
174 /* The return value of tagged_types_tu_compatible_p if we had seen
175 these two types already. */
176 int val;
177 };
178
179 static const struct tagged_tu_seen_cache * tagged_tu_seen_base;
180 static void free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *);
181
182 /* Do `exp = require_complete_type (exp);' to make sure exp
183 does not have an incomplete type. (That includes void types.) */
184
185 tree
186 require_complete_type (tree value)
187 {
188 tree type = TREE_TYPE (value);
189
190 if (value == error_mark_node || type == error_mark_node)
191 return error_mark_node;
192
193 /* First, detect a valid value with a complete type. */
194 if (COMPLETE_TYPE_P (type))
195 return value;
196
197 c_incomplete_type_error (value, type);
198 return error_mark_node;
199 }
200
201 /* Print an error message for invalid use of an incomplete type.
202 VALUE is the expression that was used (or 0 if that isn't known)
203 and TYPE is the type that was invalid. */
204
205 void
206 c_incomplete_type_error (const_tree value, const_tree type)
207 {
208 const char *type_code_string;
209
210 /* Avoid duplicate error message. */
211 if (TREE_CODE (type) == ERROR_MARK)
212 return;
213
214 if (value != 0 && (TREE_CODE (value) == VAR_DECL
215 || TREE_CODE (value) == PARM_DECL))
216 error ("%qD has an incomplete type", value);
217 else
218 {
219 retry:
220 /* We must print an error message. Be clever about what it says. */
221
222 switch (TREE_CODE (type))
223 {
224 case RECORD_TYPE:
225 type_code_string = "struct";
226 break;
227
228 case UNION_TYPE:
229 type_code_string = "union";
230 break;
231
232 case ENUMERAL_TYPE:
233 type_code_string = "enum";
234 break;
235
236 case VOID_TYPE:
237 error ("invalid use of void expression");
238 return;
239
240 case ARRAY_TYPE:
241 if (TYPE_DOMAIN (type))
242 {
243 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
244 {
245 error ("invalid use of flexible array member");
246 return;
247 }
248 type = TREE_TYPE (type);
249 goto retry;
250 }
251 error ("invalid use of array with unspecified bounds");
252 return;
253
254 default:
255 gcc_unreachable ();
256 }
257
258 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
259 error ("invalid use of undefined type %<%s %E%>",
260 type_code_string, TYPE_NAME (type));
261 else
262 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
263 error ("invalid use of incomplete typedef %qD", TYPE_NAME (type));
264 }
265 }
266
267 /* Given a type, apply default promotions wrt unnamed function
268 arguments and return the new type. */
269
270 tree
271 c_type_promotes_to (tree type)
272 {
273 if (TYPE_MAIN_VARIANT (type) == float_type_node)
274 return double_type_node;
275
276 if (c_promoting_integer_type_p (type))
277 {
278 /* Preserve unsignedness if not really getting any wider. */
279 if (TYPE_UNSIGNED (type)
280 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
281 return unsigned_type_node;
282 return integer_type_node;
283 }
284
285 return type;
286 }
287
288 /* Return true if between two named address spaces, whether there is a superset
289 named address space that encompasses both address spaces. If there is a
290 superset, return which address space is the superset. */
291
292 static bool
293 addr_space_superset (addr_space_t as1, addr_space_t as2, addr_space_t *common)
294 {
295 if (as1 == as2)
296 {
297 *common = as1;
298 return true;
299 }
300 else if (targetm.addr_space.subset_p (as1, as2))
301 {
302 *common = as2;
303 return true;
304 }
305 else if (targetm.addr_space.subset_p (as2, as1))
306 {
307 *common = as1;
308 return true;
309 }
310 else
311 return false;
312 }
313
314 /* Return a variant of TYPE which has all the type qualifiers of LIKE
315 as well as those of TYPE. */
316
317 static tree
318 qualify_type (tree type, tree like)
319 {
320 addr_space_t as_type = TYPE_ADDR_SPACE (type);
321 addr_space_t as_like = TYPE_ADDR_SPACE (like);
322 addr_space_t as_common;
323
324 /* If the two named address spaces are different, determine the common
325 superset address space. If there isn't one, raise an error. */
326 if (!addr_space_superset (as_type, as_like, &as_common))
327 {
328 as_common = as_type;
329 error ("%qT and %qT are in disjoint named address spaces",
330 type, like);
331 }
332
333 return c_build_qualified_type (type,
334 TYPE_QUALS_NO_ADDR_SPACE (type)
335 | TYPE_QUALS_NO_ADDR_SPACE (like)
336 | ENCODE_QUAL_ADDR_SPACE (as_common));
337 }
338
339 /* Return true iff the given tree T is a variable length array. */
340
341 bool
342 c_vla_type_p (const_tree t)
343 {
344 if (TREE_CODE (t) == ARRAY_TYPE
345 && C_TYPE_VARIABLE_SIZE (t))
346 return true;
347 return false;
348 }
349 \f
350 /* Return the composite type of two compatible types.
351
352 We assume that comptypes has already been done and returned
353 nonzero; if that isn't so, this may crash. In particular, we
354 assume that qualifiers match. */
355
356 tree
357 composite_type (tree t1, tree t2)
358 {
359 enum tree_code code1;
360 enum tree_code code2;
361 tree attributes;
362
363 /* Save time if the two types are the same. */
364
365 if (t1 == t2) return t1;
366
367 /* If one type is nonsense, use the other. */
368 if (t1 == error_mark_node)
369 return t2;
370 if (t2 == error_mark_node)
371 return t1;
372
373 code1 = TREE_CODE (t1);
374 code2 = TREE_CODE (t2);
375
376 /* Merge the attributes. */
377 attributes = targetm.merge_type_attributes (t1, t2);
378
379 /* If one is an enumerated type and the other is the compatible
380 integer type, the composite type might be either of the two
381 (DR#013 question 3). For consistency, use the enumerated type as
382 the composite type. */
383
384 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE)
385 return t1;
386 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE)
387 return t2;
388
389 gcc_assert (code1 == code2);
390
391 switch (code1)
392 {
393 case POINTER_TYPE:
394 /* For two pointers, do this recursively on the target type. */
395 {
396 tree pointed_to_1 = TREE_TYPE (t1);
397 tree pointed_to_2 = TREE_TYPE (t2);
398 tree target = composite_type (pointed_to_1, pointed_to_2);
399 t1 = build_pointer_type (target);
400 t1 = build_type_attribute_variant (t1, attributes);
401 return qualify_type (t1, t2);
402 }
403
404 case ARRAY_TYPE:
405 {
406 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
407 int quals;
408 tree unqual_elt;
409 tree d1 = TYPE_DOMAIN (t1);
410 tree d2 = TYPE_DOMAIN (t2);
411 bool d1_variable, d2_variable;
412 bool d1_zero, d2_zero;
413 bool t1_complete, t2_complete;
414
415 /* We should not have any type quals on arrays at all. */
416 gcc_assert (!TYPE_QUALS_NO_ADDR_SPACE (t1)
417 && !TYPE_QUALS_NO_ADDR_SPACE (t2));
418
419 t1_complete = COMPLETE_TYPE_P (t1);
420 t2_complete = COMPLETE_TYPE_P (t2);
421
422 d1_zero = d1 == 0 || !TYPE_MAX_VALUE (d1);
423 d2_zero = d2 == 0 || !TYPE_MAX_VALUE (d2);
424
425 d1_variable = (!d1_zero
426 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
427 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
428 d2_variable = (!d2_zero
429 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
430 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
431 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1));
432 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2));
433
434 /* Save space: see if the result is identical to one of the args. */
435 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1)
436 && (d2_variable || d2_zero || !d1_variable))
437 return build_type_attribute_variant (t1, attributes);
438 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2)
439 && (d1_variable || d1_zero || !d2_variable))
440 return build_type_attribute_variant (t2, attributes);
441
442 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
443 return build_type_attribute_variant (t1, attributes);
444 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
445 return build_type_attribute_variant (t2, attributes);
446
447 /* Merge the element types, and have a size if either arg has
448 one. We may have qualifiers on the element types. To set
449 up TYPE_MAIN_VARIANT correctly, we need to form the
450 composite of the unqualified types and add the qualifiers
451 back at the end. */
452 quals = TYPE_QUALS (strip_array_types (elt));
453 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED);
454 t1 = build_array_type (unqual_elt,
455 TYPE_DOMAIN ((TYPE_DOMAIN (t1)
456 && (d2_variable
457 || d2_zero
458 || !d1_variable))
459 ? t1
460 : t2));
461 /* Ensure a composite type involving a zero-length array type
462 is a zero-length type not an incomplete type. */
463 if (d1_zero && d2_zero
464 && (t1_complete || t2_complete)
465 && !COMPLETE_TYPE_P (t1))
466 {
467 TYPE_SIZE (t1) = bitsize_zero_node;
468 TYPE_SIZE_UNIT (t1) = size_zero_node;
469 }
470 t1 = c_build_qualified_type (t1, quals);
471 return build_type_attribute_variant (t1, attributes);
472 }
473
474 case ENUMERAL_TYPE:
475 case RECORD_TYPE:
476 case UNION_TYPE:
477 if (attributes != NULL)
478 {
479 /* Try harder not to create a new aggregate type. */
480 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
481 return t1;
482 if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
483 return t2;
484 }
485 return build_type_attribute_variant (t1, attributes);
486
487 case FUNCTION_TYPE:
488 /* Function types: prefer the one that specified arg types.
489 If both do, merge the arg types. Also merge the return types. */
490 {
491 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
492 tree p1 = TYPE_ARG_TYPES (t1);
493 tree p2 = TYPE_ARG_TYPES (t2);
494 int len;
495 tree newargs, n;
496 int i;
497
498 /* Save space: see if the result is identical to one of the args. */
499 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2))
500 return build_type_attribute_variant (t1, attributes);
501 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1))
502 return build_type_attribute_variant (t2, attributes);
503
504 /* Simple way if one arg fails to specify argument types. */
505 if (TYPE_ARG_TYPES (t1) == 0)
506 {
507 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
508 t1 = build_type_attribute_variant (t1, attributes);
509 return qualify_type (t1, t2);
510 }
511 if (TYPE_ARG_TYPES (t2) == 0)
512 {
513 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
514 t1 = build_type_attribute_variant (t1, attributes);
515 return qualify_type (t1, t2);
516 }
517
518 /* If both args specify argument types, we must merge the two
519 lists, argument by argument. */
520 /* Tell global_bindings_p to return false so that variable_size
521 doesn't die on VLAs in parameter types. */
522 c_override_global_bindings_to_false = true;
523
524 len = list_length (p1);
525 newargs = 0;
526
527 for (i = 0; i < len; i++)
528 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
529
530 n = newargs;
531
532 for (; p1;
533 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
534 {
535 /* A null type means arg type is not specified.
536 Take whatever the other function type has. */
537 if (TREE_VALUE (p1) == 0)
538 {
539 TREE_VALUE (n) = TREE_VALUE (p2);
540 goto parm_done;
541 }
542 if (TREE_VALUE (p2) == 0)
543 {
544 TREE_VALUE (n) = TREE_VALUE (p1);
545 goto parm_done;
546 }
547
548 /* Given wait (union {union wait *u; int *i} *)
549 and wait (union wait *),
550 prefer union wait * as type of parm. */
551 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
552 && TREE_VALUE (p1) != TREE_VALUE (p2))
553 {
554 tree memb;
555 tree mv2 = TREE_VALUE (p2);
556 if (mv2 && mv2 != error_mark_node
557 && TREE_CODE (mv2) != ARRAY_TYPE)
558 mv2 = TYPE_MAIN_VARIANT (mv2);
559 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
560 memb; memb = TREE_CHAIN (memb))
561 {
562 tree mv3 = TREE_TYPE (memb);
563 if (mv3 && mv3 != error_mark_node
564 && TREE_CODE (mv3) != ARRAY_TYPE)
565 mv3 = TYPE_MAIN_VARIANT (mv3);
566 if (comptypes (mv3, mv2))
567 {
568 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
569 TREE_VALUE (p2));
570 pedwarn (input_location, OPT_pedantic,
571 "function types not truly compatible in ISO C");
572 goto parm_done;
573 }
574 }
575 }
576 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
577 && TREE_VALUE (p2) != TREE_VALUE (p1))
578 {
579 tree memb;
580 tree mv1 = TREE_VALUE (p1);
581 if (mv1 && mv1 != error_mark_node
582 && TREE_CODE (mv1) != ARRAY_TYPE)
583 mv1 = TYPE_MAIN_VARIANT (mv1);
584 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
585 memb; memb = TREE_CHAIN (memb))
586 {
587 tree mv3 = TREE_TYPE (memb);
588 if (mv3 && mv3 != error_mark_node
589 && TREE_CODE (mv3) != ARRAY_TYPE)
590 mv3 = TYPE_MAIN_VARIANT (mv3);
591 if (comptypes (mv3, mv1))
592 {
593 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
594 TREE_VALUE (p1));
595 pedwarn (input_location, OPT_pedantic,
596 "function types not truly compatible in ISO C");
597 goto parm_done;
598 }
599 }
600 }
601 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2));
602 parm_done: ;
603 }
604
605 c_override_global_bindings_to_false = false;
606 t1 = build_function_type (valtype, newargs);
607 t1 = qualify_type (t1, t2);
608 /* ... falls through ... */
609 }
610
611 default:
612 return build_type_attribute_variant (t1, attributes);
613 }
614
615 }
616
617 /* Return the type of a conditional expression between pointers to
618 possibly differently qualified versions of compatible types.
619
620 We assume that comp_target_types has already been done and returned
621 nonzero; if that isn't so, this may crash. */
622
623 static tree
624 common_pointer_type (tree t1, tree t2)
625 {
626 tree attributes;
627 tree pointed_to_1, mv1;
628 tree pointed_to_2, mv2;
629 tree target;
630 unsigned target_quals;
631 addr_space_t as1, as2, as_common;
632 int quals1, quals2;
633
634 /* Save time if the two types are the same. */
635
636 if (t1 == t2) return t1;
637
638 /* If one type is nonsense, use the other. */
639 if (t1 == error_mark_node)
640 return t2;
641 if (t2 == error_mark_node)
642 return t1;
643
644 gcc_assert (TREE_CODE (t1) == POINTER_TYPE
645 && TREE_CODE (t2) == POINTER_TYPE);
646
647 /* Merge the attributes. */
648 attributes = targetm.merge_type_attributes (t1, t2);
649
650 /* Find the composite type of the target types, and combine the
651 qualifiers of the two types' targets. Do not lose qualifiers on
652 array element types by taking the TYPE_MAIN_VARIANT. */
653 mv1 = pointed_to_1 = TREE_TYPE (t1);
654 mv2 = pointed_to_2 = TREE_TYPE (t2);
655 if (TREE_CODE (mv1) != ARRAY_TYPE)
656 mv1 = TYPE_MAIN_VARIANT (pointed_to_1);
657 if (TREE_CODE (mv2) != ARRAY_TYPE)
658 mv2 = TYPE_MAIN_VARIANT (pointed_to_2);
659 target = composite_type (mv1, mv2);
660
661 /* For function types do not merge const qualifiers, but drop them
662 if used inconsistently. The middle-end uses these to mark const
663 and noreturn functions. */
664 quals1 = TYPE_QUALS_NO_ADDR_SPACE (pointed_to_1);
665 quals2 = TYPE_QUALS_NO_ADDR_SPACE (pointed_to_2);
666
667 if (TREE_CODE (pointed_to_1) == FUNCTION_TYPE)
668 target_quals = (quals1 & quals2);
669 else
670 target_quals = (quals1 | quals2);
671
672 /* If the two named address spaces are different, determine the common
673 superset address space. This is guaranteed to exist due to the
674 assumption that comp_target_type returned non-zero. */
675 as1 = TYPE_ADDR_SPACE (pointed_to_1);
676 as2 = TYPE_ADDR_SPACE (pointed_to_2);
677 if (!addr_space_superset (as1, as2, &as_common))
678 gcc_unreachable ();
679
680 target_quals |= ENCODE_QUAL_ADDR_SPACE (as_common);
681
682 t1 = build_pointer_type (c_build_qualified_type (target, target_quals));
683 return build_type_attribute_variant (t1, attributes);
684 }
685
686 /* Return the common type for two arithmetic types under the usual
687 arithmetic conversions. The default conversions have already been
688 applied, and enumerated types converted to their compatible integer
689 types. The resulting type is unqualified and has no attributes.
690
691 This is the type for the result of most arithmetic operations
692 if the operands have the given two types. */
693
694 static tree
695 c_common_type (tree t1, tree t2)
696 {
697 enum tree_code code1;
698 enum tree_code code2;
699
700 /* If one type is nonsense, use the other. */
701 if (t1 == error_mark_node)
702 return t2;
703 if (t2 == error_mark_node)
704 return t1;
705
706 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED)
707 t1 = TYPE_MAIN_VARIANT (t1);
708
709 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED)
710 t2 = TYPE_MAIN_VARIANT (t2);
711
712 if (TYPE_ATTRIBUTES (t1) != NULL_TREE)
713 t1 = build_type_attribute_variant (t1, NULL_TREE);
714
715 if (TYPE_ATTRIBUTES (t2) != NULL_TREE)
716 t2 = build_type_attribute_variant (t2, NULL_TREE);
717
718 /* Save time if the two types are the same. */
719
720 if (t1 == t2) return t1;
721
722 code1 = TREE_CODE (t1);
723 code2 = TREE_CODE (t2);
724
725 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE
726 || code1 == FIXED_POINT_TYPE || code1 == REAL_TYPE
727 || code1 == INTEGER_TYPE);
728 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE
729 || code2 == FIXED_POINT_TYPE || code2 == REAL_TYPE
730 || code2 == INTEGER_TYPE);
731
732 /* When one operand is a decimal float type, the other operand cannot be
733 a generic float type or a complex type. We also disallow vector types
734 here. */
735 if ((DECIMAL_FLOAT_TYPE_P (t1) || DECIMAL_FLOAT_TYPE_P (t2))
736 && !(DECIMAL_FLOAT_TYPE_P (t1) && DECIMAL_FLOAT_TYPE_P (t2)))
737 {
738 if (code1 == VECTOR_TYPE || code2 == VECTOR_TYPE)
739 {
740 error ("can%'t mix operands of decimal float and vector types");
741 return error_mark_node;
742 }
743 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
744 {
745 error ("can%'t mix operands of decimal float and complex types");
746 return error_mark_node;
747 }
748 if (code1 == REAL_TYPE && code2 == REAL_TYPE)
749 {
750 error ("can%'t mix operands of decimal float and other float types");
751 return error_mark_node;
752 }
753 }
754
755 /* If one type is a vector type, return that type. (How the usual
756 arithmetic conversions apply to the vector types extension is not
757 precisely specified.) */
758 if (code1 == VECTOR_TYPE)
759 return t1;
760
761 if (code2 == VECTOR_TYPE)
762 return t2;
763
764 /* If one type is complex, form the common type of the non-complex
765 components, then make that complex. Use T1 or T2 if it is the
766 required type. */
767 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
768 {
769 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
770 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
771 tree subtype = c_common_type (subtype1, subtype2);
772
773 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
774 return t1;
775 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
776 return t2;
777 else
778 return build_complex_type (subtype);
779 }
780
781 /* If only one is real, use it as the result. */
782
783 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
784 return t1;
785
786 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
787 return t2;
788
789 /* If both are real and either are decimal floating point types, use
790 the decimal floating point type with the greater precision. */
791
792 if (code1 == REAL_TYPE && code2 == REAL_TYPE)
793 {
794 if (TYPE_MAIN_VARIANT (t1) == dfloat128_type_node
795 || TYPE_MAIN_VARIANT (t2) == dfloat128_type_node)
796 return dfloat128_type_node;
797 else if (TYPE_MAIN_VARIANT (t1) == dfloat64_type_node
798 || TYPE_MAIN_VARIANT (t2) == dfloat64_type_node)
799 return dfloat64_type_node;
800 else if (TYPE_MAIN_VARIANT (t1) == dfloat32_type_node
801 || TYPE_MAIN_VARIANT (t2) == dfloat32_type_node)
802 return dfloat32_type_node;
803 }
804
805 /* Deal with fixed-point types. */
806 if (code1 == FIXED_POINT_TYPE || code2 == FIXED_POINT_TYPE)
807 {
808 unsigned int unsignedp = 0, satp = 0;
809 enum machine_mode m1, m2;
810 unsigned int fbit1, ibit1, fbit2, ibit2, max_fbit, max_ibit;
811
812 m1 = TYPE_MODE (t1);
813 m2 = TYPE_MODE (t2);
814
815 /* If one input type is saturating, the result type is saturating. */
816 if (TYPE_SATURATING (t1) || TYPE_SATURATING (t2))
817 satp = 1;
818
819 /* If both fixed-point types are unsigned, the result type is unsigned.
820 When mixing fixed-point and integer types, follow the sign of the
821 fixed-point type.
822 Otherwise, the result type is signed. */
823 if ((TYPE_UNSIGNED (t1) && TYPE_UNSIGNED (t2)
824 && code1 == FIXED_POINT_TYPE && code2 == FIXED_POINT_TYPE)
825 || (code1 == FIXED_POINT_TYPE && code2 != FIXED_POINT_TYPE
826 && TYPE_UNSIGNED (t1))
827 || (code1 != FIXED_POINT_TYPE && code2 == FIXED_POINT_TYPE
828 && TYPE_UNSIGNED (t2)))
829 unsignedp = 1;
830
831 /* The result type is signed. */
832 if (unsignedp == 0)
833 {
834 /* If the input type is unsigned, we need to convert to the
835 signed type. */
836 if (code1 == FIXED_POINT_TYPE && TYPE_UNSIGNED (t1))
837 {
838 enum mode_class mclass = (enum mode_class) 0;
839 if (GET_MODE_CLASS (m1) == MODE_UFRACT)
840 mclass = MODE_FRACT;
841 else if (GET_MODE_CLASS (m1) == MODE_UACCUM)
842 mclass = MODE_ACCUM;
843 else
844 gcc_unreachable ();
845 m1 = mode_for_size (GET_MODE_PRECISION (m1), mclass, 0);
846 }
847 if (code2 == FIXED_POINT_TYPE && TYPE_UNSIGNED (t2))
848 {
849 enum mode_class mclass = (enum mode_class) 0;
850 if (GET_MODE_CLASS (m2) == MODE_UFRACT)
851 mclass = MODE_FRACT;
852 else if (GET_MODE_CLASS (m2) == MODE_UACCUM)
853 mclass = MODE_ACCUM;
854 else
855 gcc_unreachable ();
856 m2 = mode_for_size (GET_MODE_PRECISION (m2), mclass, 0);
857 }
858 }
859
860 if (code1 == FIXED_POINT_TYPE)
861 {
862 fbit1 = GET_MODE_FBIT (m1);
863 ibit1 = GET_MODE_IBIT (m1);
864 }
865 else
866 {
867 fbit1 = 0;
868 /* Signed integers need to subtract one sign bit. */
869 ibit1 = TYPE_PRECISION (t1) - (!TYPE_UNSIGNED (t1));
870 }
871
872 if (code2 == FIXED_POINT_TYPE)
873 {
874 fbit2 = GET_MODE_FBIT (m2);
875 ibit2 = GET_MODE_IBIT (m2);
876 }
877 else
878 {
879 fbit2 = 0;
880 /* Signed integers need to subtract one sign bit. */
881 ibit2 = TYPE_PRECISION (t2) - (!TYPE_UNSIGNED (t2));
882 }
883
884 max_ibit = ibit1 >= ibit2 ? ibit1 : ibit2;
885 max_fbit = fbit1 >= fbit2 ? fbit1 : fbit2;
886 return c_common_fixed_point_type_for_size (max_ibit, max_fbit, unsignedp,
887 satp);
888 }
889
890 /* Both real or both integers; use the one with greater precision. */
891
892 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
893 return t1;
894 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
895 return t2;
896
897 /* Same precision. Prefer long longs to longs to ints when the
898 same precision, following the C99 rules on integer type rank
899 (which are equivalent to the C90 rules for C90 types). */
900
901 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node
902 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node)
903 return long_long_unsigned_type_node;
904
905 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node
906 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node)
907 {
908 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
909 return long_long_unsigned_type_node;
910 else
911 return long_long_integer_type_node;
912 }
913
914 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
915 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
916 return long_unsigned_type_node;
917
918 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
919 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
920 {
921 /* But preserve unsignedness from the other type,
922 since long cannot hold all the values of an unsigned int. */
923 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
924 return long_unsigned_type_node;
925 else
926 return long_integer_type_node;
927 }
928
929 /* Likewise, prefer long double to double even if same size. */
930 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
931 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
932 return long_double_type_node;
933
934 /* Otherwise prefer the unsigned one. */
935
936 if (TYPE_UNSIGNED (t1))
937 return t1;
938 else
939 return t2;
940 }
941 \f
942 /* Wrapper around c_common_type that is used by c-common.c and other
943 front end optimizations that remove promotions. ENUMERAL_TYPEs
944 are allowed here and are converted to their compatible integer types.
945 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or
946 preferably a non-Boolean type as the common type. */
947 tree
948 common_type (tree t1, tree t2)
949 {
950 if (TREE_CODE (t1) == ENUMERAL_TYPE)
951 t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1);
952 if (TREE_CODE (t2) == ENUMERAL_TYPE)
953 t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1);
954
955 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */
956 if (TREE_CODE (t1) == BOOLEAN_TYPE
957 && TREE_CODE (t2) == BOOLEAN_TYPE)
958 return boolean_type_node;
959
960 /* If either type is BOOLEAN_TYPE, then return the other. */
961 if (TREE_CODE (t1) == BOOLEAN_TYPE)
962 return t2;
963 if (TREE_CODE (t2) == BOOLEAN_TYPE)
964 return t1;
965
966 return c_common_type (t1, t2);
967 }
968
969 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
970 or various other operations. Return 2 if they are compatible
971 but a warning may be needed if you use them together. */
972
973 int
974 comptypes (tree type1, tree type2)
975 {
976 const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base;
977 int val;
978
979 val = comptypes_internal (type1, type2, NULL);
980 free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1);
981
982 return val;
983 }
984
985 /* Like comptypes, but if it returns non-zero because enum and int are
986 compatible, it sets *ENUM_AND_INT_P to true. */
987
988 static int
989 comptypes_check_enum_int (tree type1, tree type2, bool *enum_and_int_p)
990 {
991 const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base;
992 int val;
993
994 val = comptypes_internal (type1, type2, enum_and_int_p);
995 free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1);
996
997 return val;
998 }
999 \f
1000 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
1001 or various other operations. Return 2 if they are compatible
1002 but a warning may be needed if you use them together. If
1003 ENUM_AND_INT_P is not NULL, and one type is an enum and the other a
1004 compatible integer type, then this sets *ENUM_AND_INT_P to true;
1005 *ENUM_AND_INT_P is never set to false. This differs from
1006 comptypes, in that we don't free the seen types. */
1007
1008 static int
1009 comptypes_internal (const_tree type1, const_tree type2, bool *enum_and_int_p)
1010 {
1011 const_tree t1 = type1;
1012 const_tree t2 = type2;
1013 int attrval, val;
1014
1015 /* Suppress errors caused by previously reported errors. */
1016
1017 if (t1 == t2 || !t1 || !t2
1018 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
1019 return 1;
1020
1021 /* If either type is the internal version of sizetype, return the
1022 language version. */
1023 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
1024 && TYPE_ORIG_SIZE_TYPE (t1))
1025 t1 = TYPE_ORIG_SIZE_TYPE (t1);
1026
1027 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
1028 && TYPE_ORIG_SIZE_TYPE (t2))
1029 t2 = TYPE_ORIG_SIZE_TYPE (t2);
1030
1031
1032 /* Enumerated types are compatible with integer types, but this is
1033 not transitive: two enumerated types in the same translation unit
1034 are compatible with each other only if they are the same type. */
1035
1036 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE)
1037 {
1038 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1));
1039 if (enum_and_int_p != NULL && TREE_CODE (t2) != VOID_TYPE)
1040 *enum_and_int_p = true;
1041 }
1042 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE)
1043 {
1044 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2));
1045 if (enum_and_int_p != NULL && TREE_CODE (t1) != VOID_TYPE)
1046 *enum_and_int_p = true;
1047 }
1048
1049 if (t1 == t2)
1050 return 1;
1051
1052 /* Different classes of types can't be compatible. */
1053
1054 if (TREE_CODE (t1) != TREE_CODE (t2))
1055 return 0;
1056
1057 /* Qualifiers must match. C99 6.7.3p9 */
1058
1059 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
1060 return 0;
1061
1062 /* Allow for two different type nodes which have essentially the same
1063 definition. Note that we already checked for equality of the type
1064 qualifiers (just above). */
1065
1066 if (TREE_CODE (t1) != ARRAY_TYPE
1067 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
1068 return 1;
1069
1070 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1071 if (!(attrval = targetm.comp_type_attributes (t1, t2)))
1072 return 0;
1073
1074 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1075 val = 0;
1076
1077 switch (TREE_CODE (t1))
1078 {
1079 case POINTER_TYPE:
1080 /* Do not remove mode or aliasing information. */
1081 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1082 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
1083 break;
1084 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
1085 ? 1 : comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2),
1086 enum_and_int_p));
1087 break;
1088
1089 case FUNCTION_TYPE:
1090 val = function_types_compatible_p (t1, t2, enum_and_int_p);
1091 break;
1092
1093 case ARRAY_TYPE:
1094 {
1095 tree d1 = TYPE_DOMAIN (t1);
1096 tree d2 = TYPE_DOMAIN (t2);
1097 bool d1_variable, d2_variable;
1098 bool d1_zero, d2_zero;
1099 val = 1;
1100
1101 /* Target types must match incl. qualifiers. */
1102 if (TREE_TYPE (t1) != TREE_TYPE (t2)
1103 && 0 == (val = comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2),
1104 enum_and_int_p)))
1105 return 0;
1106
1107 /* Sizes must match unless one is missing or variable. */
1108 if (d1 == 0 || d2 == 0 || d1 == d2)
1109 break;
1110
1111 d1_zero = !TYPE_MAX_VALUE (d1);
1112 d2_zero = !TYPE_MAX_VALUE (d2);
1113
1114 d1_variable = (!d1_zero
1115 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
1116 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
1117 d2_variable = (!d2_zero
1118 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
1119 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
1120 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1));
1121 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2));
1122
1123 if (d1_variable || d2_variable)
1124 break;
1125 if (d1_zero && d2_zero)
1126 break;
1127 if (d1_zero || d2_zero
1128 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
1129 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
1130 val = 0;
1131
1132 break;
1133 }
1134
1135 case ENUMERAL_TYPE:
1136 case RECORD_TYPE:
1137 case UNION_TYPE:
1138 if (val != 1 && !same_translation_unit_p (t1, t2))
1139 {
1140 tree a1 = TYPE_ATTRIBUTES (t1);
1141 tree a2 = TYPE_ATTRIBUTES (t2);
1142
1143 if (! attribute_list_contained (a1, a2)
1144 && ! attribute_list_contained (a2, a1))
1145 break;
1146
1147 if (attrval != 2)
1148 return tagged_types_tu_compatible_p (t1, t2, enum_and_int_p);
1149 val = tagged_types_tu_compatible_p (t1, t2, enum_and_int_p);
1150 }
1151 break;
1152
1153 case VECTOR_TYPE:
1154 val = (TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
1155 && comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2),
1156 enum_and_int_p));
1157 break;
1158
1159 default:
1160 break;
1161 }
1162 return attrval == 2 && val == 1 ? 2 : val;
1163 }
1164
1165 /* Return 1 if TTL and TTR are pointers to types that are equivalent, ignoring
1166 their qualifiers, except for named address spaces. If the pointers point to
1167 different named addresses, then we must determine if one address space is a
1168 subset of the other. */
1169
1170 static int
1171 comp_target_types (location_t location, tree ttl, tree ttr)
1172 {
1173 int val;
1174 tree mvl = TREE_TYPE (ttl);
1175 tree mvr = TREE_TYPE (ttr);
1176 addr_space_t asl = TYPE_ADDR_SPACE (mvl);
1177 addr_space_t asr = TYPE_ADDR_SPACE (mvr);
1178 addr_space_t as_common;
1179 bool enum_and_int_p;
1180
1181 /* Fail if pointers point to incompatible address spaces. */
1182 if (!addr_space_superset (asl, asr, &as_common))
1183 return 0;
1184
1185 /* Do not lose qualifiers on element types of array types that are
1186 pointer targets by taking their TYPE_MAIN_VARIANT. */
1187 if (TREE_CODE (mvl) != ARRAY_TYPE)
1188 mvl = TYPE_MAIN_VARIANT (mvl);
1189 if (TREE_CODE (mvr) != ARRAY_TYPE)
1190 mvr = TYPE_MAIN_VARIANT (mvr);
1191 enum_and_int_p = false;
1192 val = comptypes_check_enum_int (mvl, mvr, &enum_and_int_p);
1193
1194 if (val == 2)
1195 pedwarn (location, OPT_pedantic, "types are not quite compatible");
1196
1197 if (val == 1 && enum_and_int_p && warn_cxx_compat)
1198 warning_at (location, OPT_Wc___compat,
1199 "pointer target types incompatible in C++");
1200
1201 return val;
1202 }
1203 \f
1204 /* Subroutines of `comptypes'. */
1205
1206 /* Determine whether two trees derive from the same translation unit.
1207 If the CONTEXT chain ends in a null, that tree's context is still
1208 being parsed, so if two trees have context chains ending in null,
1209 they're in the same translation unit. */
1210 int
1211 same_translation_unit_p (const_tree t1, const_tree t2)
1212 {
1213 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL)
1214 switch (TREE_CODE_CLASS (TREE_CODE (t1)))
1215 {
1216 case tcc_declaration:
1217 t1 = DECL_CONTEXT (t1); break;
1218 case tcc_type:
1219 t1 = TYPE_CONTEXT (t1); break;
1220 case tcc_exceptional:
1221 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */
1222 default: gcc_unreachable ();
1223 }
1224
1225 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL)
1226 switch (TREE_CODE_CLASS (TREE_CODE (t2)))
1227 {
1228 case tcc_declaration:
1229 t2 = DECL_CONTEXT (t2); break;
1230 case tcc_type:
1231 t2 = TYPE_CONTEXT (t2); break;
1232 case tcc_exceptional:
1233 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */
1234 default: gcc_unreachable ();
1235 }
1236
1237 return t1 == t2;
1238 }
1239
1240 /* Allocate the seen two types, assuming that they are compatible. */
1241
1242 static struct tagged_tu_seen_cache *
1243 alloc_tagged_tu_seen_cache (const_tree t1, const_tree t2)
1244 {
1245 struct tagged_tu_seen_cache *tu = XNEW (struct tagged_tu_seen_cache);
1246 tu->next = tagged_tu_seen_base;
1247 tu->t1 = t1;
1248 tu->t2 = t2;
1249
1250 tagged_tu_seen_base = tu;
1251
1252 /* The C standard says that two structures in different translation
1253 units are compatible with each other only if the types of their
1254 fields are compatible (among other things). We assume that they
1255 are compatible until proven otherwise when building the cache.
1256 An example where this can occur is:
1257 struct a
1258 {
1259 struct a *next;
1260 };
1261 If we are comparing this against a similar struct in another TU,
1262 and did not assume they were compatible, we end up with an infinite
1263 loop. */
1264 tu->val = 1;
1265 return tu;
1266 }
1267
1268 /* Free the seen types until we get to TU_TIL. */
1269
1270 static void
1271 free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *tu_til)
1272 {
1273 const struct tagged_tu_seen_cache *tu = tagged_tu_seen_base;
1274 while (tu != tu_til)
1275 {
1276 const struct tagged_tu_seen_cache *const tu1
1277 = (const struct tagged_tu_seen_cache *) tu;
1278 tu = tu1->next;
1279 free (CONST_CAST (struct tagged_tu_seen_cache *, tu1));
1280 }
1281 tagged_tu_seen_base = tu_til;
1282 }
1283
1284 /* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
1285 compatible. If the two types are not the same (which has been
1286 checked earlier), this can only happen when multiple translation
1287 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
1288 rules. ENUM_AND_INT_P is as in comptypes_internal. */
1289
1290 static int
1291 tagged_types_tu_compatible_p (const_tree t1, const_tree t2,
1292 bool *enum_and_int_p)
1293 {
1294 tree s1, s2;
1295 bool needs_warning = false;
1296
1297 /* We have to verify that the tags of the types are the same. This
1298 is harder than it looks because this may be a typedef, so we have
1299 to go look at the original type. It may even be a typedef of a
1300 typedef...
1301 In the case of compiler-created builtin structs the TYPE_DECL
1302 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
1303 while (TYPE_NAME (t1)
1304 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL
1305 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1)))
1306 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1));
1307
1308 while (TYPE_NAME (t2)
1309 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL
1310 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2)))
1311 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2));
1312
1313 /* C90 didn't have the requirement that the two tags be the same. */
1314 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2))
1315 return 0;
1316
1317 /* C90 didn't say what happened if one or both of the types were
1318 incomplete; we choose to follow C99 rules here, which is that they
1319 are compatible. */
1320 if (TYPE_SIZE (t1) == NULL
1321 || TYPE_SIZE (t2) == NULL)
1322 return 1;
1323
1324 {
1325 const struct tagged_tu_seen_cache * tts_i;
1326 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next)
1327 if (tts_i->t1 == t1 && tts_i->t2 == t2)
1328 return tts_i->val;
1329 }
1330
1331 switch (TREE_CODE (t1))
1332 {
1333 case ENUMERAL_TYPE:
1334 {
1335 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1336 /* Speed up the case where the type values are in the same order. */
1337 tree tv1 = TYPE_VALUES (t1);
1338 tree tv2 = TYPE_VALUES (t2);
1339
1340 if (tv1 == tv2)
1341 {
1342 return 1;
1343 }
1344
1345 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2))
1346 {
1347 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2))
1348 break;
1349 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1)
1350 {
1351 tu->val = 0;
1352 return 0;
1353 }
1354 }
1355
1356 if (tv1 == NULL_TREE && tv2 == NULL_TREE)
1357 {
1358 return 1;
1359 }
1360 if (tv1 == NULL_TREE || tv2 == NULL_TREE)
1361 {
1362 tu->val = 0;
1363 return 0;
1364 }
1365
1366 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2)))
1367 {
1368 tu->val = 0;
1369 return 0;
1370 }
1371
1372 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1))
1373 {
1374 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2));
1375 if (s2 == NULL
1376 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1)
1377 {
1378 tu->val = 0;
1379 return 0;
1380 }
1381 }
1382 return 1;
1383 }
1384
1385 case UNION_TYPE:
1386 {
1387 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1388 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2)))
1389 {
1390 tu->val = 0;
1391 return 0;
1392 }
1393
1394 /* Speed up the common case where the fields are in the same order. */
1395 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2); s1 && s2;
1396 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1397 {
1398 int result;
1399
1400 if (DECL_NAME (s1) != DECL_NAME (s2))
1401 break;
1402 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2),
1403 enum_and_int_p);
1404
1405 if (result != 1 && !DECL_NAME (s1))
1406 break;
1407 if (result == 0)
1408 {
1409 tu->val = 0;
1410 return 0;
1411 }
1412 if (result == 2)
1413 needs_warning = true;
1414
1415 if (TREE_CODE (s1) == FIELD_DECL
1416 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1417 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1418 {
1419 tu->val = 0;
1420 return 0;
1421 }
1422 }
1423 if (!s1 && !s2)
1424 {
1425 tu->val = needs_warning ? 2 : 1;
1426 return tu->val;
1427 }
1428
1429 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1))
1430 {
1431 bool ok = false;
1432
1433 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2))
1434 if (DECL_NAME (s1) == DECL_NAME (s2))
1435 {
1436 int result;
1437
1438 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2),
1439 enum_and_int_p);
1440
1441 if (result != 1 && !DECL_NAME (s1))
1442 continue;
1443 if (result == 0)
1444 {
1445 tu->val = 0;
1446 return 0;
1447 }
1448 if (result == 2)
1449 needs_warning = true;
1450
1451 if (TREE_CODE (s1) == FIELD_DECL
1452 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1453 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1454 break;
1455
1456 ok = true;
1457 break;
1458 }
1459 if (!ok)
1460 {
1461 tu->val = 0;
1462 return 0;
1463 }
1464 }
1465 tu->val = needs_warning ? 2 : 10;
1466 return tu->val;
1467 }
1468
1469 case RECORD_TYPE:
1470 {
1471 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1472
1473 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2);
1474 s1 && s2;
1475 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1476 {
1477 int result;
1478 if (TREE_CODE (s1) != TREE_CODE (s2)
1479 || DECL_NAME (s1) != DECL_NAME (s2))
1480 break;
1481 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2),
1482 enum_and_int_p);
1483 if (result == 0)
1484 break;
1485 if (result == 2)
1486 needs_warning = true;
1487
1488 if (TREE_CODE (s1) == FIELD_DECL
1489 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1490 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1491 break;
1492 }
1493 if (s1 && s2)
1494 tu->val = 0;
1495 else
1496 tu->val = needs_warning ? 2 : 1;
1497 return tu->val;
1498 }
1499
1500 default:
1501 gcc_unreachable ();
1502 }
1503 }
1504
1505 /* Return 1 if two function types F1 and F2 are compatible.
1506 If either type specifies no argument types,
1507 the other must specify a fixed number of self-promoting arg types.
1508 Otherwise, if one type specifies only the number of arguments,
1509 the other must specify that number of self-promoting arg types.
1510 Otherwise, the argument types must match.
1511 ENUM_AND_INT_P is as in comptypes_internal. */
1512
1513 static int
1514 function_types_compatible_p (const_tree f1, const_tree f2,
1515 bool *enum_and_int_p)
1516 {
1517 tree args1, args2;
1518 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1519 int val = 1;
1520 int val1;
1521 tree ret1, ret2;
1522
1523 ret1 = TREE_TYPE (f1);
1524 ret2 = TREE_TYPE (f2);
1525
1526 /* 'volatile' qualifiers on a function's return type used to mean
1527 the function is noreturn. */
1528 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2))
1529 pedwarn (input_location, 0, "function return types not compatible due to %<volatile%>");
1530 if (TYPE_VOLATILE (ret1))
1531 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1),
1532 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE);
1533 if (TYPE_VOLATILE (ret2))
1534 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2),
1535 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE);
1536 val = comptypes_internal (ret1, ret2, enum_and_int_p);
1537 if (val == 0)
1538 return 0;
1539
1540 args1 = TYPE_ARG_TYPES (f1);
1541 args2 = TYPE_ARG_TYPES (f2);
1542
1543 /* An unspecified parmlist matches any specified parmlist
1544 whose argument types don't need default promotions. */
1545
1546 if (args1 == 0)
1547 {
1548 if (!self_promoting_args_p (args2))
1549 return 0;
1550 /* If one of these types comes from a non-prototype fn definition,
1551 compare that with the other type's arglist.
1552 If they don't match, ask for a warning (but no error). */
1553 if (TYPE_ACTUAL_ARG_TYPES (f1)
1554 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1),
1555 enum_and_int_p))
1556 val = 2;
1557 return val;
1558 }
1559 if (args2 == 0)
1560 {
1561 if (!self_promoting_args_p (args1))
1562 return 0;
1563 if (TYPE_ACTUAL_ARG_TYPES (f2)
1564 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2),
1565 enum_and_int_p))
1566 val = 2;
1567 return val;
1568 }
1569
1570 /* Both types have argument lists: compare them and propagate results. */
1571 val1 = type_lists_compatible_p (args1, args2, enum_and_int_p);
1572 return val1 != 1 ? val1 : val;
1573 }
1574
1575 /* Check two lists of types for compatibility, returning 0 for
1576 incompatible, 1 for compatible, or 2 for compatible with
1577 warning. ENUM_AND_INT_P is as in comptypes_internal. */
1578
1579 static int
1580 type_lists_compatible_p (const_tree args1, const_tree args2,
1581 bool *enum_and_int_p)
1582 {
1583 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1584 int val = 1;
1585 int newval = 0;
1586
1587 while (1)
1588 {
1589 tree a1, mv1, a2, mv2;
1590 if (args1 == 0 && args2 == 0)
1591 return val;
1592 /* If one list is shorter than the other,
1593 they fail to match. */
1594 if (args1 == 0 || args2 == 0)
1595 return 0;
1596 mv1 = a1 = TREE_VALUE (args1);
1597 mv2 = a2 = TREE_VALUE (args2);
1598 if (mv1 && mv1 != error_mark_node && TREE_CODE (mv1) != ARRAY_TYPE)
1599 mv1 = TYPE_MAIN_VARIANT (mv1);
1600 if (mv2 && mv2 != error_mark_node && TREE_CODE (mv2) != ARRAY_TYPE)
1601 mv2 = TYPE_MAIN_VARIANT (mv2);
1602 /* A null pointer instead of a type
1603 means there is supposed to be an argument
1604 but nothing is specified about what type it has.
1605 So match anything that self-promotes. */
1606 if (a1 == 0)
1607 {
1608 if (c_type_promotes_to (a2) != a2)
1609 return 0;
1610 }
1611 else if (a2 == 0)
1612 {
1613 if (c_type_promotes_to (a1) != a1)
1614 return 0;
1615 }
1616 /* If one of the lists has an error marker, ignore this arg. */
1617 else if (TREE_CODE (a1) == ERROR_MARK
1618 || TREE_CODE (a2) == ERROR_MARK)
1619 ;
1620 else if (!(newval = comptypes_internal (mv1, mv2, enum_and_int_p)))
1621 {
1622 /* Allow wait (union {union wait *u; int *i} *)
1623 and wait (union wait *) to be compatible. */
1624 if (TREE_CODE (a1) == UNION_TYPE
1625 && (TYPE_NAME (a1) == 0
1626 || TYPE_TRANSPARENT_AGGR (a1))
1627 && TREE_CODE (TYPE_SIZE (a1)) == INTEGER_CST
1628 && tree_int_cst_equal (TYPE_SIZE (a1),
1629 TYPE_SIZE (a2)))
1630 {
1631 tree memb;
1632 for (memb = TYPE_FIELDS (a1);
1633 memb; memb = TREE_CHAIN (memb))
1634 {
1635 tree mv3 = TREE_TYPE (memb);
1636 if (mv3 && mv3 != error_mark_node
1637 && TREE_CODE (mv3) != ARRAY_TYPE)
1638 mv3 = TYPE_MAIN_VARIANT (mv3);
1639 if (comptypes_internal (mv3, mv2, enum_and_int_p))
1640 break;
1641 }
1642 if (memb == 0)
1643 return 0;
1644 }
1645 else if (TREE_CODE (a2) == UNION_TYPE
1646 && (TYPE_NAME (a2) == 0
1647 || TYPE_TRANSPARENT_AGGR (a2))
1648 && TREE_CODE (TYPE_SIZE (a2)) == INTEGER_CST
1649 && tree_int_cst_equal (TYPE_SIZE (a2),
1650 TYPE_SIZE (a1)))
1651 {
1652 tree memb;
1653 for (memb = TYPE_FIELDS (a2);
1654 memb; memb = TREE_CHAIN (memb))
1655 {
1656 tree mv3 = TREE_TYPE (memb);
1657 if (mv3 && mv3 != error_mark_node
1658 && TREE_CODE (mv3) != ARRAY_TYPE)
1659 mv3 = TYPE_MAIN_VARIANT (mv3);
1660 if (comptypes_internal (mv3, mv1, enum_and_int_p))
1661 break;
1662 }
1663 if (memb == 0)
1664 return 0;
1665 }
1666 else
1667 return 0;
1668 }
1669
1670 /* comptypes said ok, but record if it said to warn. */
1671 if (newval > val)
1672 val = newval;
1673
1674 args1 = TREE_CHAIN (args1);
1675 args2 = TREE_CHAIN (args2);
1676 }
1677 }
1678 \f
1679 /* Compute the size to increment a pointer by. */
1680
1681 static tree
1682 c_size_in_bytes (const_tree type)
1683 {
1684 enum tree_code code = TREE_CODE (type);
1685
1686 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
1687 return size_one_node;
1688
1689 if (!COMPLETE_OR_VOID_TYPE_P (type))
1690 {
1691 error ("arithmetic on pointer to an incomplete type");
1692 return size_one_node;
1693 }
1694
1695 /* Convert in case a char is more than one unit. */
1696 return size_binop_loc (input_location, CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
1697 size_int (TYPE_PRECISION (char_type_node)
1698 / BITS_PER_UNIT));
1699 }
1700 \f
1701 /* Return either DECL or its known constant value (if it has one). */
1702
1703 tree
1704 decl_constant_value (tree decl)
1705 {
1706 if (/* Don't change a variable array bound or initial value to a constant
1707 in a place where a variable is invalid. Note that DECL_INITIAL
1708 isn't valid for a PARM_DECL. */
1709 current_function_decl != 0
1710 && TREE_CODE (decl) != PARM_DECL
1711 && !TREE_THIS_VOLATILE (decl)
1712 && TREE_READONLY (decl)
1713 && DECL_INITIAL (decl) != 0
1714 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
1715 /* This is invalid if initial value is not constant.
1716 If it has either a function call, a memory reference,
1717 or a variable, then re-evaluating it could give different results. */
1718 && TREE_CONSTANT (DECL_INITIAL (decl))
1719 /* Check for cases where this is sub-optimal, even though valid. */
1720 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
1721 return DECL_INITIAL (decl);
1722 return decl;
1723 }
1724
1725 /* Convert the array expression EXP to a pointer. */
1726 static tree
1727 array_to_pointer_conversion (location_t loc, tree exp)
1728 {
1729 tree orig_exp = exp;
1730 tree type = TREE_TYPE (exp);
1731 tree adr;
1732 tree restype = TREE_TYPE (type);
1733 tree ptrtype;
1734
1735 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
1736
1737 STRIP_TYPE_NOPS (exp);
1738
1739 if (TREE_NO_WARNING (orig_exp))
1740 TREE_NO_WARNING (exp) = 1;
1741
1742 ptrtype = build_pointer_type (restype);
1743
1744 if (TREE_CODE (exp) == INDIRECT_REF)
1745 return convert (ptrtype, TREE_OPERAND (exp, 0));
1746
1747 adr = build_unary_op (loc, ADDR_EXPR, exp, 1);
1748 return convert (ptrtype, adr);
1749 }
1750
1751 /* Convert the function expression EXP to a pointer. */
1752 static tree
1753 function_to_pointer_conversion (location_t loc, tree exp)
1754 {
1755 tree orig_exp = exp;
1756
1757 gcc_assert (TREE_CODE (TREE_TYPE (exp)) == FUNCTION_TYPE);
1758
1759 STRIP_TYPE_NOPS (exp);
1760
1761 if (TREE_NO_WARNING (orig_exp))
1762 TREE_NO_WARNING (exp) = 1;
1763
1764 return build_unary_op (loc, ADDR_EXPR, exp, 0);
1765 }
1766
1767 /* Mark EXP as read, not just set, for set but not used -Wunused
1768 warning purposes. */
1769
1770 void
1771 mark_exp_read (tree exp)
1772 {
1773 switch (TREE_CODE (exp))
1774 {
1775 case VAR_DECL:
1776 case PARM_DECL:
1777 DECL_READ_P (exp) = 1;
1778 break;
1779 case ARRAY_REF:
1780 case COMPONENT_REF:
1781 case MODIFY_EXPR:
1782 case REALPART_EXPR:
1783 case IMAGPART_EXPR:
1784 CASE_CONVERT:
1785 case ADDR_EXPR:
1786 mark_exp_read (TREE_OPERAND (exp, 0));
1787 break;
1788 case COMPOUND_EXPR:
1789 mark_exp_read (TREE_OPERAND (exp, 1));
1790 break;
1791 default:
1792 break;
1793 }
1794 }
1795
1796 /* Perform the default conversion of arrays and functions to pointers.
1797 Return the result of converting EXP. For any other expression, just
1798 return EXP.
1799
1800 LOC is the location of the expression. */
1801
1802 struct c_expr
1803 default_function_array_conversion (location_t loc, struct c_expr exp)
1804 {
1805 tree orig_exp = exp.value;
1806 tree type = TREE_TYPE (exp.value);
1807 enum tree_code code = TREE_CODE (type);
1808
1809 switch (code)
1810 {
1811 case ARRAY_TYPE:
1812 {
1813 bool not_lvalue = false;
1814 bool lvalue_array_p;
1815
1816 while ((TREE_CODE (exp.value) == NON_LVALUE_EXPR
1817 || CONVERT_EXPR_P (exp.value))
1818 && TREE_TYPE (TREE_OPERAND (exp.value, 0)) == type)
1819 {
1820 if (TREE_CODE (exp.value) == NON_LVALUE_EXPR)
1821 not_lvalue = true;
1822 exp.value = TREE_OPERAND (exp.value, 0);
1823 }
1824
1825 if (TREE_NO_WARNING (orig_exp))
1826 TREE_NO_WARNING (exp.value) = 1;
1827
1828 lvalue_array_p = !not_lvalue && lvalue_p (exp.value);
1829 if (!flag_isoc99 && !lvalue_array_p)
1830 {
1831 /* Before C99, non-lvalue arrays do not decay to pointers.
1832 Normally, using such an array would be invalid; but it can
1833 be used correctly inside sizeof or as a statement expression.
1834 Thus, do not give an error here; an error will result later. */
1835 return exp;
1836 }
1837
1838 exp.value = array_to_pointer_conversion (loc, exp.value);
1839 }
1840 break;
1841 case FUNCTION_TYPE:
1842 exp.value = function_to_pointer_conversion (loc, exp.value);
1843 break;
1844 default:
1845 break;
1846 }
1847
1848 return exp;
1849 }
1850
1851 struct c_expr
1852 default_function_array_read_conversion (location_t loc, struct c_expr exp)
1853 {
1854 mark_exp_read (exp.value);
1855 return default_function_array_conversion (loc, exp);
1856 }
1857
1858 /* EXP is an expression of integer type. Apply the integer promotions
1859 to it and return the promoted value. */
1860
1861 tree
1862 perform_integral_promotions (tree exp)
1863 {
1864 tree type = TREE_TYPE (exp);
1865 enum tree_code code = TREE_CODE (type);
1866
1867 gcc_assert (INTEGRAL_TYPE_P (type));
1868
1869 /* Normally convert enums to int,
1870 but convert wide enums to something wider. */
1871 if (code == ENUMERAL_TYPE)
1872 {
1873 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
1874 TYPE_PRECISION (integer_type_node)),
1875 ((TYPE_PRECISION (type)
1876 >= TYPE_PRECISION (integer_type_node))
1877 && TYPE_UNSIGNED (type)));
1878
1879 return convert (type, exp);
1880 }
1881
1882 /* ??? This should no longer be needed now bit-fields have their
1883 proper types. */
1884 if (TREE_CODE (exp) == COMPONENT_REF
1885 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
1886 /* If it's thinner than an int, promote it like a
1887 c_promoting_integer_type_p, otherwise leave it alone. */
1888 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
1889 TYPE_PRECISION (integer_type_node)))
1890 return convert (integer_type_node, exp);
1891
1892 if (c_promoting_integer_type_p (type))
1893 {
1894 /* Preserve unsignedness if not really getting any wider. */
1895 if (TYPE_UNSIGNED (type)
1896 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1897 return convert (unsigned_type_node, exp);
1898
1899 return convert (integer_type_node, exp);
1900 }
1901
1902 return exp;
1903 }
1904
1905
1906 /* Perform default promotions for C data used in expressions.
1907 Enumeral types or short or char are converted to int.
1908 In addition, manifest constants symbols are replaced by their values. */
1909
1910 tree
1911 default_conversion (tree exp)
1912 {
1913 tree orig_exp;
1914 tree type = TREE_TYPE (exp);
1915 enum tree_code code = TREE_CODE (type);
1916 tree promoted_type;
1917
1918 mark_exp_read (exp);
1919
1920 /* Functions and arrays have been converted during parsing. */
1921 gcc_assert (code != FUNCTION_TYPE);
1922 if (code == ARRAY_TYPE)
1923 return exp;
1924
1925 /* Constants can be used directly unless they're not loadable. */
1926 if (TREE_CODE (exp) == CONST_DECL)
1927 exp = DECL_INITIAL (exp);
1928
1929 /* Strip no-op conversions. */
1930 orig_exp = exp;
1931 STRIP_TYPE_NOPS (exp);
1932
1933 if (TREE_NO_WARNING (orig_exp))
1934 TREE_NO_WARNING (exp) = 1;
1935
1936 if (code == VOID_TYPE)
1937 {
1938 error ("void value not ignored as it ought to be");
1939 return error_mark_node;
1940 }
1941
1942 exp = require_complete_type (exp);
1943 if (exp == error_mark_node)
1944 return error_mark_node;
1945
1946 promoted_type = targetm.promoted_type (type);
1947 if (promoted_type)
1948 return convert (promoted_type, exp);
1949
1950 if (INTEGRAL_TYPE_P (type))
1951 return perform_integral_promotions (exp);
1952
1953 return exp;
1954 }
1955 \f
1956 /* Look up COMPONENT in a structure or union DECL.
1957
1958 If the component name is not found, returns NULL_TREE. Otherwise,
1959 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1960 stepping down the chain to the component, which is in the last
1961 TREE_VALUE of the list. Normally the list is of length one, but if
1962 the component is embedded within (nested) anonymous structures or
1963 unions, the list steps down the chain to the component. */
1964
1965 static tree
1966 lookup_field (tree decl, tree component)
1967 {
1968 tree type = TREE_TYPE (decl);
1969 tree field;
1970
1971 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1972 to the field elements. Use a binary search on this array to quickly
1973 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1974 will always be set for structures which have many elements. */
1975
1976 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s)
1977 {
1978 int bot, top, half;
1979 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0];
1980
1981 field = TYPE_FIELDS (type);
1982 bot = 0;
1983 top = TYPE_LANG_SPECIFIC (type)->s->len;
1984 while (top - bot > 1)
1985 {
1986 half = (top - bot + 1) >> 1;
1987 field = field_array[bot+half];
1988
1989 if (DECL_NAME (field) == NULL_TREE)
1990 {
1991 /* Step through all anon unions in linear fashion. */
1992 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1993 {
1994 field = field_array[bot++];
1995 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1996 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1997 {
1998 tree anon = lookup_field (field, component);
1999
2000 if (anon)
2001 return tree_cons (NULL_TREE, field, anon);
2002 }
2003 }
2004
2005 /* Entire record is only anon unions. */
2006 if (bot > top)
2007 return NULL_TREE;
2008
2009 /* Restart the binary search, with new lower bound. */
2010 continue;
2011 }
2012
2013 if (DECL_NAME (field) == component)
2014 break;
2015 if (DECL_NAME (field) < component)
2016 bot += half;
2017 else
2018 top = bot + half;
2019 }
2020
2021 if (DECL_NAME (field_array[bot]) == component)
2022 field = field_array[bot];
2023 else if (DECL_NAME (field) != component)
2024 return NULL_TREE;
2025 }
2026 else
2027 {
2028 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
2029 {
2030 if (DECL_NAME (field) == NULL_TREE
2031 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
2032 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
2033 {
2034 tree anon = lookup_field (field, component);
2035
2036 if (anon)
2037 return tree_cons (NULL_TREE, field, anon);
2038 }
2039
2040 if (DECL_NAME (field) == component)
2041 break;
2042 }
2043
2044 if (field == NULL_TREE)
2045 return NULL_TREE;
2046 }
2047
2048 return tree_cons (NULL_TREE, field, NULL_TREE);
2049 }
2050
2051 /* Make an expression to refer to the COMPONENT field of structure or
2052 union value DATUM. COMPONENT is an IDENTIFIER_NODE. LOC is the
2053 location of the COMPONENT_REF. */
2054
2055 tree
2056 build_component_ref (location_t loc, tree datum, tree component)
2057 {
2058 tree type = TREE_TYPE (datum);
2059 enum tree_code code = TREE_CODE (type);
2060 tree field = NULL;
2061 tree ref;
2062 bool datum_lvalue = lvalue_p (datum);
2063
2064 if (!objc_is_public (datum, component))
2065 return error_mark_node;
2066
2067 /* See if there is a field or component with name COMPONENT. */
2068
2069 if (code == RECORD_TYPE || code == UNION_TYPE)
2070 {
2071 if (!COMPLETE_TYPE_P (type))
2072 {
2073 c_incomplete_type_error (NULL_TREE, type);
2074 return error_mark_node;
2075 }
2076
2077 field = lookup_field (datum, component);
2078
2079 if (!field)
2080 {
2081 error_at (loc, "%qT has no member named %qE", type, component);
2082 return error_mark_node;
2083 }
2084
2085 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
2086 This might be better solved in future the way the C++ front
2087 end does it - by giving the anonymous entities each a
2088 separate name and type, and then have build_component_ref
2089 recursively call itself. We can't do that here. */
2090 do
2091 {
2092 tree subdatum = TREE_VALUE (field);
2093 int quals;
2094 tree subtype;
2095 bool use_datum_quals;
2096
2097 if (TREE_TYPE (subdatum) == error_mark_node)
2098 return error_mark_node;
2099
2100 /* If this is an rvalue, it does not have qualifiers in C
2101 standard terms and we must avoid propagating such
2102 qualifiers down to a non-lvalue array that is then
2103 converted to a pointer. */
2104 use_datum_quals = (datum_lvalue
2105 || TREE_CODE (TREE_TYPE (subdatum)) != ARRAY_TYPE);
2106
2107 quals = TYPE_QUALS (strip_array_types (TREE_TYPE (subdatum)));
2108 if (use_datum_quals)
2109 quals |= TYPE_QUALS (TREE_TYPE (datum));
2110 subtype = c_build_qualified_type (TREE_TYPE (subdatum), quals);
2111
2112 ref = build3 (COMPONENT_REF, subtype, datum, subdatum,
2113 NULL_TREE);
2114 SET_EXPR_LOCATION (ref, loc);
2115 if (TREE_READONLY (subdatum)
2116 || (use_datum_quals && TREE_READONLY (datum)))
2117 TREE_READONLY (ref) = 1;
2118 if (TREE_THIS_VOLATILE (subdatum)
2119 || (use_datum_quals && TREE_THIS_VOLATILE (datum)))
2120 TREE_THIS_VOLATILE (ref) = 1;
2121
2122 if (TREE_DEPRECATED (subdatum))
2123 warn_deprecated_use (subdatum, NULL_TREE);
2124
2125 datum = ref;
2126
2127 field = TREE_CHAIN (field);
2128 }
2129 while (field);
2130
2131 return ref;
2132 }
2133 else if (code != ERROR_MARK)
2134 error_at (loc,
2135 "request for member %qE in something not a structure or union",
2136 component);
2137
2138 return error_mark_node;
2139 }
2140 \f
2141 /* Given an expression PTR for a pointer, return an expression
2142 for the value pointed to.
2143 ERRORSTRING is the name of the operator to appear in error messages.
2144
2145 LOC is the location to use for the generated tree. */
2146
2147 tree
2148 build_indirect_ref (location_t loc, tree ptr, ref_operator errstring)
2149 {
2150 tree pointer = default_conversion (ptr);
2151 tree type = TREE_TYPE (pointer);
2152 tree ref;
2153
2154 if (TREE_CODE (type) == POINTER_TYPE)
2155 {
2156 if (CONVERT_EXPR_P (pointer)
2157 || TREE_CODE (pointer) == VIEW_CONVERT_EXPR)
2158 {
2159 /* If a warning is issued, mark it to avoid duplicates from
2160 the backend. This only needs to be done at
2161 warn_strict_aliasing > 2. */
2162 if (warn_strict_aliasing > 2)
2163 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (pointer, 0)),
2164 type, TREE_OPERAND (pointer, 0)))
2165 TREE_NO_WARNING (pointer) = 1;
2166 }
2167
2168 if (TREE_CODE (pointer) == ADDR_EXPR
2169 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
2170 == TREE_TYPE (type)))
2171 {
2172 ref = TREE_OPERAND (pointer, 0);
2173 protected_set_expr_location (ref, loc);
2174 return ref;
2175 }
2176 else
2177 {
2178 tree t = TREE_TYPE (type);
2179
2180 ref = build1 (INDIRECT_REF, t, pointer);
2181
2182 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
2183 {
2184 error_at (loc, "dereferencing pointer to incomplete type");
2185 return error_mark_node;
2186 }
2187 if (VOID_TYPE_P (t) && c_inhibit_evaluation_warnings == 0)
2188 warning_at (loc, 0, "dereferencing %<void *%> pointer");
2189
2190 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2191 so that we get the proper error message if the result is used
2192 to assign to. Also, &* is supposed to be a no-op.
2193 And ANSI C seems to specify that the type of the result
2194 should be the const type. */
2195 /* A de-reference of a pointer to const is not a const. It is valid
2196 to change it via some other pointer. */
2197 TREE_READONLY (ref) = TYPE_READONLY (t);
2198 TREE_SIDE_EFFECTS (ref)
2199 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
2200 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
2201 protected_set_expr_location (ref, loc);
2202 return ref;
2203 }
2204 }
2205 else if (TREE_CODE (pointer) != ERROR_MARK)
2206 switch (errstring)
2207 {
2208 case RO_ARRAY_INDEXING:
2209 error_at (loc,
2210 "invalid type argument of array indexing (have %qT)",
2211 type);
2212 break;
2213 case RO_UNARY_STAR:
2214 error_at (loc,
2215 "invalid type argument of unary %<*%> (have %qT)",
2216 type);
2217 break;
2218 case RO_ARROW:
2219 error_at (loc,
2220 "invalid type argument of %<->%> (have %qT)",
2221 type);
2222 break;
2223 default:
2224 gcc_unreachable ();
2225 }
2226 return error_mark_node;
2227 }
2228
2229 /* This handles expressions of the form "a[i]", which denotes
2230 an array reference.
2231
2232 This is logically equivalent in C to *(a+i), but we may do it differently.
2233 If A is a variable or a member, we generate a primitive ARRAY_REF.
2234 This avoids forcing the array out of registers, and can work on
2235 arrays that are not lvalues (for example, members of structures returned
2236 by functions).
2237
2238 LOC is the location to use for the returned expression. */
2239
2240 tree
2241 build_array_ref (location_t loc, tree array, tree index)
2242 {
2243 tree ret;
2244 bool swapped = false;
2245 if (TREE_TYPE (array) == error_mark_node
2246 || TREE_TYPE (index) == error_mark_node)
2247 return error_mark_node;
2248
2249 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE
2250 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE)
2251 {
2252 tree temp;
2253 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE
2254 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE)
2255 {
2256 error_at (loc, "subscripted value is neither array nor pointer");
2257 return error_mark_node;
2258 }
2259 temp = array;
2260 array = index;
2261 index = temp;
2262 swapped = true;
2263 }
2264
2265 if (!INTEGRAL_TYPE_P (TREE_TYPE (index)))
2266 {
2267 error_at (loc, "array subscript is not an integer");
2268 return error_mark_node;
2269 }
2270
2271 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE)
2272 {
2273 error_at (loc, "subscripted value is pointer to function");
2274 return error_mark_node;
2275 }
2276
2277 /* ??? Existing practice has been to warn only when the char
2278 index is syntactically the index, not for char[array]. */
2279 if (!swapped)
2280 warn_array_subscript_with_type_char (index);
2281
2282 /* Apply default promotions *after* noticing character types. */
2283 index = default_conversion (index);
2284
2285 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE);
2286
2287 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2288 {
2289 tree rval, type;
2290
2291 /* An array that is indexed by a non-constant
2292 cannot be stored in a register; we must be able to do
2293 address arithmetic on its address.
2294 Likewise an array of elements of variable size. */
2295 if (TREE_CODE (index) != INTEGER_CST
2296 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2297 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
2298 {
2299 if (!c_mark_addressable (array))
2300 return error_mark_node;
2301 }
2302 /* An array that is indexed by a constant value which is not within
2303 the array bounds cannot be stored in a register either; because we
2304 would get a crash in store_bit_field/extract_bit_field when trying
2305 to access a non-existent part of the register. */
2306 if (TREE_CODE (index) == INTEGER_CST
2307 && TYPE_DOMAIN (TREE_TYPE (array))
2308 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
2309 {
2310 if (!c_mark_addressable (array))
2311 return error_mark_node;
2312 }
2313
2314 if (pedantic)
2315 {
2316 tree foo = array;
2317 while (TREE_CODE (foo) == COMPONENT_REF)
2318 foo = TREE_OPERAND (foo, 0);
2319 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
2320 pedwarn (loc, OPT_pedantic,
2321 "ISO C forbids subscripting %<register%> array");
2322 else if (!flag_isoc99 && !lvalue_p (foo))
2323 pedwarn (loc, OPT_pedantic,
2324 "ISO C90 forbids subscripting non-lvalue array");
2325 }
2326
2327 type = TREE_TYPE (TREE_TYPE (array));
2328 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE);
2329 /* Array ref is const/volatile if the array elements are
2330 or if the array is. */
2331 TREE_READONLY (rval)
2332 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
2333 | TREE_READONLY (array));
2334 TREE_SIDE_EFFECTS (rval)
2335 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2336 | TREE_SIDE_EFFECTS (array));
2337 TREE_THIS_VOLATILE (rval)
2338 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2339 /* This was added by rms on 16 Nov 91.
2340 It fixes vol struct foo *a; a->elts[1]
2341 in an inline function.
2342 Hope it doesn't break something else. */
2343 | TREE_THIS_VOLATILE (array));
2344 ret = require_complete_type (rval);
2345 protected_set_expr_location (ret, loc);
2346 return ret;
2347 }
2348 else
2349 {
2350 tree ar = default_conversion (array);
2351
2352 if (ar == error_mark_node)
2353 return ar;
2354
2355 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE);
2356 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE);
2357
2358 return build_indirect_ref
2359 (loc, build_binary_op (loc, PLUS_EXPR, ar, index, 0),
2360 RO_ARRAY_INDEXING);
2361 }
2362 }
2363 \f
2364 /* Build an external reference to identifier ID. FUN indicates
2365 whether this will be used for a function call. LOC is the source
2366 location of the identifier. This sets *TYPE to the type of the
2367 identifier, which is not the same as the type of the returned value
2368 for CONST_DECLs defined as enum constants. If the type of the
2369 identifier is not available, *TYPE is set to NULL. */
2370 tree
2371 build_external_ref (location_t loc, tree id, int fun, tree *type)
2372 {
2373 tree ref;
2374 tree decl = lookup_name (id);
2375
2376 /* In Objective-C, an instance variable (ivar) may be preferred to
2377 whatever lookup_name() found. */
2378 decl = objc_lookup_ivar (decl, id);
2379
2380 *type = NULL;
2381 if (decl && decl != error_mark_node)
2382 {
2383 ref = decl;
2384 *type = TREE_TYPE (ref);
2385 }
2386 else if (fun)
2387 /* Implicit function declaration. */
2388 ref = implicitly_declare (loc, id);
2389 else if (decl == error_mark_node)
2390 /* Don't complain about something that's already been
2391 complained about. */
2392 return error_mark_node;
2393 else
2394 {
2395 undeclared_variable (loc, id);
2396 return error_mark_node;
2397 }
2398
2399 if (TREE_TYPE (ref) == error_mark_node)
2400 return error_mark_node;
2401
2402 if (TREE_DEPRECATED (ref))
2403 warn_deprecated_use (ref, NULL_TREE);
2404
2405 /* Recursive call does not count as usage. */
2406 if (ref != current_function_decl)
2407 {
2408 TREE_USED (ref) = 1;
2409 }
2410
2411 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof)
2412 {
2413 if (!in_sizeof && !in_typeof)
2414 C_DECL_USED (ref) = 1;
2415 else if (DECL_INITIAL (ref) == 0
2416 && DECL_EXTERNAL (ref)
2417 && !TREE_PUBLIC (ref))
2418 record_maybe_used_decl (ref);
2419 }
2420
2421 if (TREE_CODE (ref) == CONST_DECL)
2422 {
2423 used_types_insert (TREE_TYPE (ref));
2424
2425 if (warn_cxx_compat
2426 && TREE_CODE (TREE_TYPE (ref)) == ENUMERAL_TYPE
2427 && C_TYPE_DEFINED_IN_STRUCT (TREE_TYPE (ref)))
2428 {
2429 warning_at (loc, OPT_Wc___compat,
2430 ("enum constant defined in struct or union "
2431 "is not visible in C++"));
2432 inform (DECL_SOURCE_LOCATION (ref), "enum constant defined here");
2433 }
2434
2435 ref = DECL_INITIAL (ref);
2436 TREE_CONSTANT (ref) = 1;
2437 }
2438 else if (current_function_decl != 0
2439 && !DECL_FILE_SCOPE_P (current_function_decl)
2440 && (TREE_CODE (ref) == VAR_DECL
2441 || TREE_CODE (ref) == PARM_DECL
2442 || TREE_CODE (ref) == FUNCTION_DECL))
2443 {
2444 tree context = decl_function_context (ref);
2445
2446 if (context != 0 && context != current_function_decl)
2447 DECL_NONLOCAL (ref) = 1;
2448 }
2449 /* C99 6.7.4p3: An inline definition of a function with external
2450 linkage ... shall not contain a reference to an identifier with
2451 internal linkage. */
2452 else if (current_function_decl != 0
2453 && DECL_DECLARED_INLINE_P (current_function_decl)
2454 && DECL_EXTERNAL (current_function_decl)
2455 && VAR_OR_FUNCTION_DECL_P (ref)
2456 && (TREE_CODE (ref) != VAR_DECL || TREE_STATIC (ref))
2457 && ! TREE_PUBLIC (ref)
2458 && DECL_CONTEXT (ref) != current_function_decl)
2459 record_inline_static (loc, current_function_decl, ref,
2460 csi_internal);
2461
2462 return ref;
2463 }
2464
2465 /* Record details of decls possibly used inside sizeof or typeof. */
2466 struct maybe_used_decl
2467 {
2468 /* The decl. */
2469 tree decl;
2470 /* The level seen at (in_sizeof + in_typeof). */
2471 int level;
2472 /* The next one at this level or above, or NULL. */
2473 struct maybe_used_decl *next;
2474 };
2475
2476 static struct maybe_used_decl *maybe_used_decls;
2477
2478 /* Record that DECL, an undefined static function reference seen
2479 inside sizeof or typeof, might be used if the operand of sizeof is
2480 a VLA type or the operand of typeof is a variably modified
2481 type. */
2482
2483 static void
2484 record_maybe_used_decl (tree decl)
2485 {
2486 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl);
2487 t->decl = decl;
2488 t->level = in_sizeof + in_typeof;
2489 t->next = maybe_used_decls;
2490 maybe_used_decls = t;
2491 }
2492
2493 /* Pop the stack of decls possibly used inside sizeof or typeof. If
2494 USED is false, just discard them. If it is true, mark them used
2495 (if no longer inside sizeof or typeof) or move them to the next
2496 level up (if still inside sizeof or typeof). */
2497
2498 void
2499 pop_maybe_used (bool used)
2500 {
2501 struct maybe_used_decl *p = maybe_used_decls;
2502 int cur_level = in_sizeof + in_typeof;
2503 while (p && p->level > cur_level)
2504 {
2505 if (used)
2506 {
2507 if (cur_level == 0)
2508 C_DECL_USED (p->decl) = 1;
2509 else
2510 p->level = cur_level;
2511 }
2512 p = p->next;
2513 }
2514 if (!used || cur_level == 0)
2515 maybe_used_decls = p;
2516 }
2517
2518 /* Return the result of sizeof applied to EXPR. */
2519
2520 struct c_expr
2521 c_expr_sizeof_expr (location_t loc, struct c_expr expr)
2522 {
2523 struct c_expr ret;
2524 if (expr.value == error_mark_node)
2525 {
2526 ret.value = error_mark_node;
2527 ret.original_code = ERROR_MARK;
2528 ret.original_type = NULL;
2529 pop_maybe_used (false);
2530 }
2531 else
2532 {
2533 bool expr_const_operands = true;
2534 tree folded_expr = c_fully_fold (expr.value, require_constant_value,
2535 &expr_const_operands);
2536 ret.value = c_sizeof (loc, TREE_TYPE (folded_expr));
2537 ret.original_code = ERROR_MARK;
2538 ret.original_type = NULL;
2539 if (c_vla_type_p (TREE_TYPE (folded_expr)))
2540 {
2541 /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */
2542 ret.value = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (ret.value),
2543 folded_expr, ret.value);
2544 C_MAYBE_CONST_EXPR_NON_CONST (ret.value) = !expr_const_operands;
2545 SET_EXPR_LOCATION (ret.value, loc);
2546 }
2547 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (folded_expr)));
2548 }
2549 return ret;
2550 }
2551
2552 /* Return the result of sizeof applied to T, a structure for the type
2553 name passed to sizeof (rather than the type itself). LOC is the
2554 location of the original expression. */
2555
2556 struct c_expr
2557 c_expr_sizeof_type (location_t loc, struct c_type_name *t)
2558 {
2559 tree type;
2560 struct c_expr ret;
2561 tree type_expr = NULL_TREE;
2562 bool type_expr_const = true;
2563 type = groktypename (t, &type_expr, &type_expr_const);
2564 ret.value = c_sizeof (loc, type);
2565 ret.original_code = ERROR_MARK;
2566 ret.original_type = NULL;
2567 if ((type_expr || TREE_CODE (ret.value) == INTEGER_CST)
2568 && c_vla_type_p (type))
2569 {
2570 /* If the type is a [*] array, it is a VLA but is represented as
2571 having a size of zero. In such a case we must ensure that
2572 the result of sizeof does not get folded to a constant by
2573 c_fully_fold, because if the size is evaluated the result is
2574 not constant and so constraints on zero or negative size
2575 arrays must not be applied when this sizeof call is inside
2576 another array declarator. */
2577 if (!type_expr)
2578 type_expr = integer_zero_node;
2579 ret.value = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (ret.value),
2580 type_expr, ret.value);
2581 C_MAYBE_CONST_EXPR_NON_CONST (ret.value) = !type_expr_const;
2582 }
2583 pop_maybe_used (type != error_mark_node
2584 ? C_TYPE_VARIABLE_SIZE (type) : false);
2585 return ret;
2586 }
2587
2588 /* Build a function call to function FUNCTION with parameters PARAMS.
2589 The function call is at LOC.
2590 PARAMS is a list--a chain of TREE_LIST nodes--in which the
2591 TREE_VALUE of each node is a parameter-expression.
2592 FUNCTION's data type may be a function type or a pointer-to-function. */
2593
2594 tree
2595 build_function_call (location_t loc, tree function, tree params)
2596 {
2597 VEC(tree,gc) *vec;
2598 tree ret;
2599
2600 vec = VEC_alloc (tree, gc, list_length (params));
2601 for (; params; params = TREE_CHAIN (params))
2602 VEC_quick_push (tree, vec, TREE_VALUE (params));
2603 ret = build_function_call_vec (loc, function, vec, NULL);
2604 VEC_free (tree, gc, vec);
2605 return ret;
2606 }
2607
2608 /* Build a function call to function FUNCTION with parameters PARAMS.
2609 ORIGTYPES, if not NULL, is a vector of types; each element is
2610 either NULL or the original type of the corresponding element in
2611 PARAMS. The original type may differ from TREE_TYPE of the
2612 parameter for enums. FUNCTION's data type may be a function type
2613 or pointer-to-function. This function changes the elements of
2614 PARAMS. */
2615
2616 tree
2617 build_function_call_vec (location_t loc, tree function, VEC(tree,gc) *params,
2618 VEC(tree,gc) *origtypes)
2619 {
2620 tree fntype, fundecl = 0;
2621 tree name = NULL_TREE, result;
2622 tree tem;
2623 int nargs;
2624 tree *argarray;
2625
2626
2627 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2628 STRIP_TYPE_NOPS (function);
2629
2630 /* Convert anything with function type to a pointer-to-function. */
2631 if (TREE_CODE (function) == FUNCTION_DECL)
2632 {
2633 /* Implement type-directed function overloading for builtins.
2634 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin
2635 handle all the type checking. The result is a complete expression
2636 that implements this function call. */
2637 tem = resolve_overloaded_builtin (loc, function, params);
2638 if (tem)
2639 return tem;
2640
2641 name = DECL_NAME (function);
2642 fundecl = function;
2643 }
2644 if (TREE_CODE (TREE_TYPE (function)) == FUNCTION_TYPE)
2645 function = function_to_pointer_conversion (loc, function);
2646
2647 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2648 expressions, like those used for ObjC messenger dispatches. */
2649 if (!VEC_empty (tree, params))
2650 function = objc_rewrite_function_call (function,
2651 VEC_index (tree, params, 0));
2652
2653 function = c_fully_fold (function, false, NULL);
2654
2655 fntype = TREE_TYPE (function);
2656
2657 if (TREE_CODE (fntype) == ERROR_MARK)
2658 return error_mark_node;
2659
2660 if (!(TREE_CODE (fntype) == POINTER_TYPE
2661 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
2662 {
2663 error_at (loc, "called object %qE is not a function", function);
2664 return error_mark_node;
2665 }
2666
2667 if (fundecl && TREE_THIS_VOLATILE (fundecl))
2668 current_function_returns_abnormally = 1;
2669
2670 /* fntype now gets the type of function pointed to. */
2671 fntype = TREE_TYPE (fntype);
2672
2673 /* Convert the parameters to the types declared in the
2674 function prototype, or apply default promotions. */
2675
2676 nargs = convert_arguments (TYPE_ARG_TYPES (fntype), params, origtypes,
2677 function, fundecl);
2678 if (nargs < 0)
2679 return error_mark_node;
2680
2681 /* Check that the function is called through a compatible prototype.
2682 If it is not, replace the call by a trap, wrapped up in a compound
2683 expression if necessary. This has the nice side-effect to prevent
2684 the tree-inliner from generating invalid assignment trees which may
2685 blow up in the RTL expander later. */
2686 if (CONVERT_EXPR_P (function)
2687 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
2688 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
2689 && !comptypes (fntype, TREE_TYPE (tem)))
2690 {
2691 tree return_type = TREE_TYPE (fntype);
2692 tree trap = build_function_call (loc, built_in_decls[BUILT_IN_TRAP],
2693 NULL_TREE);
2694 int i;
2695
2696 /* This situation leads to run-time undefined behavior. We can't,
2697 therefore, simply error unless we can prove that all possible
2698 executions of the program must execute the code. */
2699 if (warning_at (loc, 0, "function called through a non-compatible type"))
2700 /* We can, however, treat "undefined" any way we please.
2701 Call abort to encourage the user to fix the program. */
2702 inform (loc, "if this code is reached, the program will abort");
2703 /* Before the abort, allow the function arguments to exit or
2704 call longjmp. */
2705 for (i = 0; i < nargs; i++)
2706 trap = build2 (COMPOUND_EXPR, void_type_node,
2707 VEC_index (tree, params, i), trap);
2708
2709 if (VOID_TYPE_P (return_type))
2710 {
2711 if (TYPE_QUALS (return_type) != TYPE_UNQUALIFIED)
2712 pedwarn (loc, 0,
2713 "function with qualified void return type called");
2714 return trap;
2715 }
2716 else
2717 {
2718 tree rhs;
2719
2720 if (AGGREGATE_TYPE_P (return_type))
2721 rhs = build_compound_literal (loc, return_type,
2722 build_constructor (return_type, 0),
2723 false);
2724 else
2725 rhs = fold_convert_loc (loc, return_type, integer_zero_node);
2726
2727 return require_complete_type (build2 (COMPOUND_EXPR, return_type,
2728 trap, rhs));
2729 }
2730 }
2731
2732 argarray = VEC_address (tree, params);
2733
2734 /* Check that arguments to builtin functions match the expectations. */
2735 if (fundecl
2736 && DECL_BUILT_IN (fundecl)
2737 && DECL_BUILT_IN_CLASS (fundecl) == BUILT_IN_NORMAL
2738 && !check_builtin_function_arguments (fundecl, nargs, argarray))
2739 return error_mark_node;
2740
2741 /* Check that the arguments to the function are valid. */
2742 check_function_arguments (TYPE_ATTRIBUTES (fntype), nargs, argarray,
2743 TYPE_ARG_TYPES (fntype));
2744
2745 if (name != NULL_TREE
2746 && !strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10))
2747 {
2748 if (require_constant_value)
2749 result =
2750 fold_build_call_array_initializer_loc (loc, TREE_TYPE (fntype),
2751 function, nargs, argarray);
2752 else
2753 result = fold_build_call_array_loc (loc, TREE_TYPE (fntype),
2754 function, nargs, argarray);
2755 if (TREE_CODE (result) == NOP_EXPR
2756 && TREE_CODE (TREE_OPERAND (result, 0)) == INTEGER_CST)
2757 STRIP_TYPE_NOPS (result);
2758 }
2759 else
2760 result = build_call_array_loc (loc, TREE_TYPE (fntype),
2761 function, nargs, argarray);
2762
2763 if (VOID_TYPE_P (TREE_TYPE (result)))
2764 {
2765 if (TYPE_QUALS (TREE_TYPE (result)) != TYPE_UNQUALIFIED)
2766 pedwarn (loc, 0,
2767 "function with qualified void return type called");
2768 return result;
2769 }
2770 return require_complete_type (result);
2771 }
2772 \f
2773 /* Convert the argument expressions in the vector VALUES
2774 to the types in the list TYPELIST.
2775
2776 If TYPELIST is exhausted, or when an element has NULL as its type,
2777 perform the default conversions.
2778
2779 ORIGTYPES is the original types of the expressions in VALUES. This
2780 holds the type of enum values which have been converted to integral
2781 types. It may be NULL.
2782
2783 FUNCTION is a tree for the called function. It is used only for
2784 error messages, where it is formatted with %qE.
2785
2786 This is also where warnings about wrong number of args are generated.
2787
2788 Returns the actual number of arguments processed (which may be less
2789 than the length of VALUES in some error situations), or -1 on
2790 failure. */
2791
2792 static int
2793 convert_arguments (tree typelist, VEC(tree,gc) *values,
2794 VEC(tree,gc) *origtypes, tree function, tree fundecl)
2795 {
2796 tree typetail, val;
2797 unsigned int parmnum;
2798 bool error_args = false;
2799 const bool type_generic = fundecl
2800 && lookup_attribute ("type generic", TYPE_ATTRIBUTES(TREE_TYPE (fundecl)));
2801 bool type_generic_remove_excess_precision = false;
2802 tree selector;
2803
2804 /* Change pointer to function to the function itself for
2805 diagnostics. */
2806 if (TREE_CODE (function) == ADDR_EXPR
2807 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
2808 function = TREE_OPERAND (function, 0);
2809
2810 /* Handle an ObjC selector specially for diagnostics. */
2811 selector = objc_message_selector ();
2812
2813 /* For type-generic built-in functions, determine whether excess
2814 precision should be removed (classification) or not
2815 (comparison). */
2816 if (type_generic
2817 && DECL_BUILT_IN (fundecl)
2818 && DECL_BUILT_IN_CLASS (fundecl) == BUILT_IN_NORMAL)
2819 {
2820 switch (DECL_FUNCTION_CODE (fundecl))
2821 {
2822 case BUILT_IN_ISFINITE:
2823 case BUILT_IN_ISINF:
2824 case BUILT_IN_ISINF_SIGN:
2825 case BUILT_IN_ISNAN:
2826 case BUILT_IN_ISNORMAL:
2827 case BUILT_IN_FPCLASSIFY:
2828 type_generic_remove_excess_precision = true;
2829 break;
2830
2831 default:
2832 type_generic_remove_excess_precision = false;
2833 break;
2834 }
2835 }
2836
2837 /* Scan the given expressions and types, producing individual
2838 converted arguments. */
2839
2840 for (typetail = typelist, parmnum = 0;
2841 VEC_iterate (tree, values, parmnum, val);
2842 ++parmnum)
2843 {
2844 tree type = typetail ? TREE_VALUE (typetail) : 0;
2845 tree valtype = TREE_TYPE (val);
2846 tree rname = function;
2847 int argnum = parmnum + 1;
2848 const char *invalid_func_diag;
2849 bool excess_precision = false;
2850 bool npc;
2851 tree parmval;
2852
2853 if (type == void_type_node)
2854 {
2855 error_at (input_location,
2856 "too many arguments to function %qE", function);
2857 if (fundecl && !DECL_BUILT_IN (fundecl))
2858 inform (DECL_SOURCE_LOCATION (fundecl), "declared here");
2859 return parmnum;
2860 }
2861
2862 if (selector && argnum > 2)
2863 {
2864 rname = selector;
2865 argnum -= 2;
2866 }
2867
2868 npc = null_pointer_constant_p (val);
2869
2870 /* If there is excess precision and a prototype, convert once to
2871 the required type rather than converting via the semantic
2872 type. Likewise without a prototype a float value represented
2873 as long double should be converted once to double. But for
2874 type-generic classification functions excess precision must
2875 be removed here. */
2876 if (TREE_CODE (val) == EXCESS_PRECISION_EXPR
2877 && (type || !type_generic || !type_generic_remove_excess_precision))
2878 {
2879 val = TREE_OPERAND (val, 0);
2880 excess_precision = true;
2881 }
2882 val = c_fully_fold (val, false, NULL);
2883 STRIP_TYPE_NOPS (val);
2884
2885 val = require_complete_type (val);
2886
2887 if (type != 0)
2888 {
2889 /* Formal parm type is specified by a function prototype. */
2890
2891 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
2892 {
2893 error ("type of formal parameter %d is incomplete", parmnum + 1);
2894 parmval = val;
2895 }
2896 else
2897 {
2898 tree origtype;
2899
2900 /* Optionally warn about conversions that
2901 differ from the default conversions. */
2902 if (warn_traditional_conversion || warn_traditional)
2903 {
2904 unsigned int formal_prec = TYPE_PRECISION (type);
2905
2906 if (INTEGRAL_TYPE_P (type)
2907 && TREE_CODE (valtype) == REAL_TYPE)
2908 warning (0, "passing argument %d of %qE as integer "
2909 "rather than floating due to prototype",
2910 argnum, rname);
2911 if (INTEGRAL_TYPE_P (type)
2912 && TREE_CODE (valtype) == COMPLEX_TYPE)
2913 warning (0, "passing argument %d of %qE as integer "
2914 "rather than complex due to prototype",
2915 argnum, rname);
2916 else if (TREE_CODE (type) == COMPLEX_TYPE
2917 && TREE_CODE (valtype) == REAL_TYPE)
2918 warning (0, "passing argument %d of %qE as complex "
2919 "rather than floating due to prototype",
2920 argnum, rname);
2921 else if (TREE_CODE (type) == REAL_TYPE
2922 && INTEGRAL_TYPE_P (valtype))
2923 warning (0, "passing argument %d of %qE as floating "
2924 "rather than integer due to prototype",
2925 argnum, rname);
2926 else if (TREE_CODE (type) == COMPLEX_TYPE
2927 && INTEGRAL_TYPE_P (valtype))
2928 warning (0, "passing argument %d of %qE as complex "
2929 "rather than integer due to prototype",
2930 argnum, rname);
2931 else if (TREE_CODE (type) == REAL_TYPE
2932 && TREE_CODE (valtype) == COMPLEX_TYPE)
2933 warning (0, "passing argument %d of %qE as floating "
2934 "rather than complex due to prototype",
2935 argnum, rname);
2936 /* ??? At some point, messages should be written about
2937 conversions between complex types, but that's too messy
2938 to do now. */
2939 else if (TREE_CODE (type) == REAL_TYPE
2940 && TREE_CODE (valtype) == REAL_TYPE)
2941 {
2942 /* Warn if any argument is passed as `float',
2943 since without a prototype it would be `double'. */
2944 if (formal_prec == TYPE_PRECISION (float_type_node)
2945 && type != dfloat32_type_node)
2946 warning (0, "passing argument %d of %qE as %<float%> "
2947 "rather than %<double%> due to prototype",
2948 argnum, rname);
2949
2950 /* Warn if mismatch between argument and prototype
2951 for decimal float types. Warn of conversions with
2952 binary float types and of precision narrowing due to
2953 prototype. */
2954 else if (type != valtype
2955 && (type == dfloat32_type_node
2956 || type == dfloat64_type_node
2957 || type == dfloat128_type_node
2958 || valtype == dfloat32_type_node
2959 || valtype == dfloat64_type_node
2960 || valtype == dfloat128_type_node)
2961 && (formal_prec
2962 <= TYPE_PRECISION (valtype)
2963 || (type == dfloat128_type_node
2964 && (valtype
2965 != dfloat64_type_node
2966 && (valtype
2967 != dfloat32_type_node)))
2968 || (type == dfloat64_type_node
2969 && (valtype
2970 != dfloat32_type_node))))
2971 warning (0, "passing argument %d of %qE as %qT "
2972 "rather than %qT due to prototype",
2973 argnum, rname, type, valtype);
2974
2975 }
2976 /* Detect integer changing in width or signedness.
2977 These warnings are only activated with
2978 -Wtraditional-conversion, not with -Wtraditional. */
2979 else if (warn_traditional_conversion && INTEGRAL_TYPE_P (type)
2980 && INTEGRAL_TYPE_P (valtype))
2981 {
2982 tree would_have_been = default_conversion (val);
2983 tree type1 = TREE_TYPE (would_have_been);
2984
2985 if (TREE_CODE (type) == ENUMERAL_TYPE
2986 && (TYPE_MAIN_VARIANT (type)
2987 == TYPE_MAIN_VARIANT (valtype)))
2988 /* No warning if function asks for enum
2989 and the actual arg is that enum type. */
2990 ;
2991 else if (formal_prec != TYPE_PRECISION (type1))
2992 warning (OPT_Wtraditional_conversion,
2993 "passing argument %d of %qE "
2994 "with different width due to prototype",
2995 argnum, rname);
2996 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2997 ;
2998 /* Don't complain if the formal parameter type
2999 is an enum, because we can't tell now whether
3000 the value was an enum--even the same enum. */
3001 else if (TREE_CODE (type) == ENUMERAL_TYPE)
3002 ;
3003 else if (TREE_CODE (val) == INTEGER_CST
3004 && int_fits_type_p (val, type))
3005 /* Change in signedness doesn't matter
3006 if a constant value is unaffected. */
3007 ;
3008 /* If the value is extended from a narrower
3009 unsigned type, it doesn't matter whether we
3010 pass it as signed or unsigned; the value
3011 certainly is the same either way. */
3012 else if (TYPE_PRECISION (valtype) < TYPE_PRECISION (type)
3013 && TYPE_UNSIGNED (valtype))
3014 ;
3015 else if (TYPE_UNSIGNED (type))
3016 warning (OPT_Wtraditional_conversion,
3017 "passing argument %d of %qE "
3018 "as unsigned due to prototype",
3019 argnum, rname);
3020 else
3021 warning (OPT_Wtraditional_conversion,
3022 "passing argument %d of %qE "
3023 "as signed due to prototype", argnum, rname);
3024 }
3025 }
3026
3027 /* Possibly restore an EXCESS_PRECISION_EXPR for the
3028 sake of better warnings from convert_and_check. */
3029 if (excess_precision)
3030 val = build1 (EXCESS_PRECISION_EXPR, valtype, val);
3031 origtype = (origtypes == NULL
3032 ? NULL_TREE
3033 : VEC_index (tree, origtypes, parmnum));
3034 parmval = convert_for_assignment (input_location, type, val,
3035 origtype, ic_argpass, npc,
3036 fundecl, function,
3037 parmnum + 1);
3038
3039 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
3040 && INTEGRAL_TYPE_P (type)
3041 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
3042 parmval = default_conversion (parmval);
3043 }
3044 }
3045 else if (TREE_CODE (valtype) == REAL_TYPE
3046 && (TYPE_PRECISION (valtype)
3047 < TYPE_PRECISION (double_type_node))
3048 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (valtype)))
3049 {
3050 if (type_generic)
3051 parmval = val;
3052 else
3053 /* Convert `float' to `double'. */
3054 parmval = convert (double_type_node, val);
3055 }
3056 else if (excess_precision && !type_generic)
3057 /* A "double" argument with excess precision being passed
3058 without a prototype or in variable arguments. */
3059 parmval = convert (valtype, val);
3060 else if ((invalid_func_diag =
3061 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val)))
3062 {
3063 error (invalid_func_diag);
3064 return -1;
3065 }
3066 else
3067 /* Convert `short' and `char' to full-size `int'. */
3068 parmval = default_conversion (val);
3069
3070 VEC_replace (tree, values, parmnum, parmval);
3071 if (parmval == error_mark_node)
3072 error_args = true;
3073
3074 if (typetail)
3075 typetail = TREE_CHAIN (typetail);
3076 }
3077
3078 gcc_assert (parmnum == VEC_length (tree, values));
3079
3080 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
3081 {
3082 error_at (input_location,
3083 "too few arguments to function %qE", function);
3084 if (fundecl && !DECL_BUILT_IN (fundecl))
3085 inform (DECL_SOURCE_LOCATION (fundecl), "declared here");
3086 return -1;
3087 }
3088
3089 return error_args ? -1 : (int) parmnum;
3090 }
3091 \f
3092 /* This is the entry point used by the parser to build unary operators
3093 in the input. CODE, a tree_code, specifies the unary operator, and
3094 ARG is the operand. For unary plus, the C parser currently uses
3095 CONVERT_EXPR for code.
3096
3097 LOC is the location to use for the tree generated.
3098 */
3099
3100 struct c_expr
3101 parser_build_unary_op (location_t loc, enum tree_code code, struct c_expr arg)
3102 {
3103 struct c_expr result;
3104
3105 result.value = build_unary_op (loc, code, arg.value, 0);
3106 result.original_code = code;
3107 result.original_type = NULL;
3108
3109 if (TREE_OVERFLOW_P (result.value) && !TREE_OVERFLOW_P (arg.value))
3110 overflow_warning (loc, result.value);
3111
3112 return result;
3113 }
3114
3115 /* This is the entry point used by the parser to build binary operators
3116 in the input. CODE, a tree_code, specifies the binary operator, and
3117 ARG1 and ARG2 are the operands. In addition to constructing the
3118 expression, we check for operands that were written with other binary
3119 operators in a way that is likely to confuse the user.
3120
3121 LOCATION is the location of the binary operator. */
3122
3123 struct c_expr
3124 parser_build_binary_op (location_t location, enum tree_code code,
3125 struct c_expr arg1, struct c_expr arg2)
3126 {
3127 struct c_expr result;
3128
3129 enum tree_code code1 = arg1.original_code;
3130 enum tree_code code2 = arg2.original_code;
3131 tree type1 = (arg1.original_type
3132 ? arg1.original_type
3133 : TREE_TYPE (arg1.value));
3134 tree type2 = (arg2.original_type
3135 ? arg2.original_type
3136 : TREE_TYPE (arg2.value));
3137
3138 result.value = build_binary_op (location, code,
3139 arg1.value, arg2.value, 1);
3140 result.original_code = code;
3141 result.original_type = NULL;
3142
3143 if (TREE_CODE (result.value) == ERROR_MARK)
3144 return result;
3145
3146 if (location != UNKNOWN_LOCATION)
3147 protected_set_expr_location (result.value, location);
3148
3149 /* Check for cases such as x+y<<z which users are likely
3150 to misinterpret. */
3151 if (warn_parentheses)
3152 warn_about_parentheses (code, code1, arg1.value, code2, arg2.value);
3153
3154 if (warn_logical_op)
3155 warn_logical_operator (input_location, code, TREE_TYPE (result.value),
3156 code1, arg1.value, code2, arg2.value);
3157
3158 /* Warn about comparisons against string literals, with the exception
3159 of testing for equality or inequality of a string literal with NULL. */
3160 if (code == EQ_EXPR || code == NE_EXPR)
3161 {
3162 if ((code1 == STRING_CST && !integer_zerop (arg2.value))
3163 || (code2 == STRING_CST && !integer_zerop (arg1.value)))
3164 warning_at (location, OPT_Waddress,
3165 "comparison with string literal results in unspecified behavior");
3166 }
3167 else if (TREE_CODE_CLASS (code) == tcc_comparison
3168 && (code1 == STRING_CST || code2 == STRING_CST))
3169 warning_at (location, OPT_Waddress,
3170 "comparison with string literal results in unspecified behavior");
3171
3172 if (TREE_OVERFLOW_P (result.value)
3173 && !TREE_OVERFLOW_P (arg1.value)
3174 && !TREE_OVERFLOW_P (arg2.value))
3175 overflow_warning (location, result.value);
3176
3177 /* Warn about comparisons of different enum types. */
3178 if (warn_enum_compare
3179 && TREE_CODE_CLASS (code) == tcc_comparison
3180 && TREE_CODE (type1) == ENUMERAL_TYPE
3181 && TREE_CODE (type2) == ENUMERAL_TYPE
3182 && TYPE_MAIN_VARIANT (type1) != TYPE_MAIN_VARIANT (type2))
3183 warning_at (location, OPT_Wenum_compare,
3184 "comparison between %qT and %qT",
3185 type1, type2);
3186
3187 return result;
3188 }
3189 \f
3190 /* Return a tree for the difference of pointers OP0 and OP1.
3191 The resulting tree has type int. */
3192
3193 static tree
3194 pointer_diff (location_t loc, tree op0, tree op1)
3195 {
3196 tree restype = ptrdiff_type_node;
3197 tree result, inttype;
3198
3199 addr_space_t as0 = TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (op0)));
3200 addr_space_t as1 = TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (op1)));
3201 tree target_type = TREE_TYPE (TREE_TYPE (op0));
3202 tree con0, con1, lit0, lit1;
3203 tree orig_op1 = op1;
3204
3205 /* If the operands point into different address spaces, we need to
3206 explicitly convert them to pointers into the common address space
3207 before we can subtract the numerical address values. */
3208 if (as0 != as1)
3209 {
3210 addr_space_t as_common;
3211 tree common_type;
3212
3213 /* Determine the common superset address space. This is guaranteed
3214 to exist because the caller verified that comp_target_types
3215 returned non-zero. */
3216 if (!addr_space_superset (as0, as1, &as_common))
3217 gcc_unreachable ();
3218
3219 common_type = common_pointer_type (TREE_TYPE (op0), TREE_TYPE (op1));
3220 op0 = convert (common_type, op0);
3221 op1 = convert (common_type, op1);
3222 }
3223
3224 /* Determine integer type to perform computations in. This will usually
3225 be the same as the result type (ptrdiff_t), but may need to be a wider
3226 type if pointers for the address space are wider than ptrdiff_t. */
3227 if (TYPE_PRECISION (restype) < TYPE_PRECISION (TREE_TYPE (op0)))
3228 inttype = lang_hooks.types.type_for_size
3229 (TYPE_PRECISION (TREE_TYPE (op0)), 0);
3230 else
3231 inttype = restype;
3232
3233
3234 if (TREE_CODE (target_type) == VOID_TYPE)
3235 pedwarn (loc, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
3236 "pointer of type %<void *%> used in subtraction");
3237 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3238 pedwarn (loc, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
3239 "pointer to a function used in subtraction");
3240
3241 /* If the conversion to ptrdiff_type does anything like widening or
3242 converting a partial to an integral mode, we get a convert_expression
3243 that is in the way to do any simplifications.
3244 (fold-const.c doesn't know that the extra bits won't be needed.
3245 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
3246 different mode in place.)
3247 So first try to find a common term here 'by hand'; we want to cover
3248 at least the cases that occur in legal static initializers. */
3249 if (CONVERT_EXPR_P (op0)
3250 && (TYPE_PRECISION (TREE_TYPE (op0))
3251 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
3252 con0 = TREE_OPERAND (op0, 0);
3253 else
3254 con0 = op0;
3255 if (CONVERT_EXPR_P (op1)
3256 && (TYPE_PRECISION (TREE_TYPE (op1))
3257 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))))
3258 con1 = TREE_OPERAND (op1, 0);
3259 else
3260 con1 = op1;
3261
3262 if (TREE_CODE (con0) == PLUS_EXPR)
3263 {
3264 lit0 = TREE_OPERAND (con0, 1);
3265 con0 = TREE_OPERAND (con0, 0);
3266 }
3267 else
3268 lit0 = integer_zero_node;
3269
3270 if (TREE_CODE (con1) == PLUS_EXPR)
3271 {
3272 lit1 = TREE_OPERAND (con1, 1);
3273 con1 = TREE_OPERAND (con1, 0);
3274 }
3275 else
3276 lit1 = integer_zero_node;
3277
3278 if (operand_equal_p (con0, con1, 0))
3279 {
3280 op0 = lit0;
3281 op1 = lit1;
3282 }
3283
3284
3285 /* First do the subtraction as integers;
3286 then drop through to build the divide operator.
3287 Do not do default conversions on the minus operator
3288 in case restype is a short type. */
3289
3290 op0 = build_binary_op (loc,
3291 MINUS_EXPR, convert (inttype, op0),
3292 convert (inttype, op1), 0);
3293 /* This generates an error if op1 is pointer to incomplete type. */
3294 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
3295 error_at (loc, "arithmetic on pointer to an incomplete type");
3296
3297 /* This generates an error if op0 is pointer to incomplete type. */
3298 op1 = c_size_in_bytes (target_type);
3299
3300 /* Divide by the size, in easiest possible way. */
3301 result = fold_build2_loc (loc, EXACT_DIV_EXPR, inttype,
3302 op0, convert (inttype, op1));
3303
3304 /* Convert to final result type if necessary. */
3305 return convert (restype, result);
3306 }
3307 \f
3308 /* Construct and perhaps optimize a tree representation
3309 for a unary operation. CODE, a tree_code, specifies the operation
3310 and XARG is the operand.
3311 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
3312 the default promotions (such as from short to int).
3313 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
3314 allows non-lvalues; this is only used to handle conversion of non-lvalue
3315 arrays to pointers in C99.
3316
3317 LOCATION is the location of the operator. */
3318
3319 tree
3320 build_unary_op (location_t location,
3321 enum tree_code code, tree xarg, int flag)
3322 {
3323 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3324 tree arg = xarg;
3325 tree argtype = 0;
3326 enum tree_code typecode;
3327 tree val;
3328 tree ret = error_mark_node;
3329 tree eptype = NULL_TREE;
3330 int noconvert = flag;
3331 const char *invalid_op_diag;
3332 bool int_operands;
3333
3334 int_operands = EXPR_INT_CONST_OPERANDS (xarg);
3335 if (int_operands)
3336 arg = remove_c_maybe_const_expr (arg);
3337
3338 if (code != ADDR_EXPR)
3339 arg = require_complete_type (arg);
3340
3341 typecode = TREE_CODE (TREE_TYPE (arg));
3342 if (typecode == ERROR_MARK)
3343 return error_mark_node;
3344 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
3345 typecode = INTEGER_TYPE;
3346
3347 if ((invalid_op_diag
3348 = targetm.invalid_unary_op (code, TREE_TYPE (xarg))))
3349 {
3350 error_at (location, invalid_op_diag);
3351 return error_mark_node;
3352 }
3353
3354 if (TREE_CODE (arg) == EXCESS_PRECISION_EXPR)
3355 {
3356 eptype = TREE_TYPE (arg);
3357 arg = TREE_OPERAND (arg, 0);
3358 }
3359
3360 switch (code)
3361 {
3362 case CONVERT_EXPR:
3363 /* This is used for unary plus, because a CONVERT_EXPR
3364 is enough to prevent anybody from looking inside for
3365 associativity, but won't generate any code. */
3366 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
3367 || typecode == FIXED_POINT_TYPE || typecode == COMPLEX_TYPE
3368 || typecode == VECTOR_TYPE))
3369 {
3370 error_at (location, "wrong type argument to unary plus");
3371 return error_mark_node;
3372 }
3373 else if (!noconvert)
3374 arg = default_conversion (arg);
3375 arg = non_lvalue_loc (location, arg);
3376 break;
3377
3378 case NEGATE_EXPR:
3379 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
3380 || typecode == FIXED_POINT_TYPE || typecode == COMPLEX_TYPE
3381 || typecode == VECTOR_TYPE))
3382 {
3383 error_at (location, "wrong type argument to unary minus");
3384 return error_mark_node;
3385 }
3386 else if (!noconvert)
3387 arg = default_conversion (arg);
3388 break;
3389
3390 case BIT_NOT_EXPR:
3391 /* ~ works on integer types and non float vectors. */
3392 if (typecode == INTEGER_TYPE
3393 || (typecode == VECTOR_TYPE
3394 && !VECTOR_FLOAT_TYPE_P (TREE_TYPE (arg))))
3395 {
3396 if (!noconvert)
3397 arg = default_conversion (arg);
3398 }
3399 else if (typecode == COMPLEX_TYPE)
3400 {
3401 code = CONJ_EXPR;
3402 pedwarn (location, OPT_pedantic,
3403 "ISO C does not support %<~%> for complex conjugation");
3404 if (!noconvert)
3405 arg = default_conversion (arg);
3406 }
3407 else
3408 {
3409 error_at (location, "wrong type argument to bit-complement");
3410 return error_mark_node;
3411 }
3412 break;
3413
3414 case ABS_EXPR:
3415 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
3416 {
3417 error_at (location, "wrong type argument to abs");
3418 return error_mark_node;
3419 }
3420 else if (!noconvert)
3421 arg = default_conversion (arg);
3422 break;
3423
3424 case CONJ_EXPR:
3425 /* Conjugating a real value is a no-op, but allow it anyway. */
3426 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
3427 || typecode == COMPLEX_TYPE))
3428 {
3429 error_at (location, "wrong type argument to conjugation");
3430 return error_mark_node;
3431 }
3432 else if (!noconvert)
3433 arg = default_conversion (arg);
3434 break;
3435
3436 case TRUTH_NOT_EXPR:
3437 if (typecode != INTEGER_TYPE && typecode != FIXED_POINT_TYPE
3438 && typecode != REAL_TYPE && typecode != POINTER_TYPE
3439 && typecode != COMPLEX_TYPE)
3440 {
3441 error_at (location,
3442 "wrong type argument to unary exclamation mark");
3443 return error_mark_node;
3444 }
3445 arg = c_objc_common_truthvalue_conversion (location, arg);
3446 ret = invert_truthvalue_loc (location, arg);
3447 /* If the TRUTH_NOT_EXPR has been folded, reset the location. */
3448 if (EXPR_P (ret) && EXPR_HAS_LOCATION (ret))
3449 location = EXPR_LOCATION (ret);
3450 goto return_build_unary_op;
3451
3452 case REALPART_EXPR:
3453 if (TREE_CODE (arg) == COMPLEX_CST)
3454 ret = TREE_REALPART (arg);
3455 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3456 ret = fold_build1_loc (location,
3457 REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3458 else
3459 ret = arg;
3460 if (eptype && TREE_CODE (eptype) == COMPLEX_TYPE)
3461 eptype = TREE_TYPE (eptype);
3462 goto return_build_unary_op;
3463
3464 case IMAGPART_EXPR:
3465 if (TREE_CODE (arg) == COMPLEX_CST)
3466 ret = TREE_IMAGPART (arg);
3467 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3468 ret = fold_build1_loc (location,
3469 IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3470 else
3471 ret = omit_one_operand_loc (location, TREE_TYPE (arg),
3472 integer_zero_node, arg);
3473 if (eptype && TREE_CODE (eptype) == COMPLEX_TYPE)
3474 eptype = TREE_TYPE (eptype);
3475 goto return_build_unary_op;
3476
3477 case PREINCREMENT_EXPR:
3478 case POSTINCREMENT_EXPR:
3479 case PREDECREMENT_EXPR:
3480 case POSTDECREMENT_EXPR:
3481
3482 if (TREE_CODE (arg) == C_MAYBE_CONST_EXPR)
3483 {
3484 tree inner = build_unary_op (location, code,
3485 C_MAYBE_CONST_EXPR_EXPR (arg), flag);
3486 if (inner == error_mark_node)
3487 return error_mark_node;
3488 ret = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (inner),
3489 C_MAYBE_CONST_EXPR_PRE (arg), inner);
3490 gcc_assert (!C_MAYBE_CONST_EXPR_INT_OPERANDS (arg));
3491 C_MAYBE_CONST_EXPR_NON_CONST (ret) = 1;
3492 goto return_build_unary_op;
3493 }
3494
3495 /* Complain about anything that is not a true lvalue. */
3496 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
3497 || code == POSTINCREMENT_EXPR)
3498 ? lv_increment
3499 : lv_decrement)))
3500 return error_mark_node;
3501
3502 if (warn_cxx_compat && TREE_CODE (TREE_TYPE (arg)) == ENUMERAL_TYPE)
3503 {
3504 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3505 warning_at (location, OPT_Wc___compat,
3506 "increment of enumeration value is invalid in C++");
3507 else
3508 warning_at (location, OPT_Wc___compat,
3509 "decrement of enumeration value is invalid in C++");
3510 }
3511
3512 /* Ensure the argument is fully folded inside any SAVE_EXPR. */
3513 arg = c_fully_fold (arg, false, NULL);
3514
3515 /* Increment or decrement the real part of the value,
3516 and don't change the imaginary part. */
3517 if (typecode == COMPLEX_TYPE)
3518 {
3519 tree real, imag;
3520
3521 pedwarn (location, OPT_pedantic,
3522 "ISO C does not support %<++%> and %<--%> on complex types");
3523
3524 arg = stabilize_reference (arg);
3525 real = build_unary_op (EXPR_LOCATION (arg), REALPART_EXPR, arg, 1);
3526 imag = build_unary_op (EXPR_LOCATION (arg), IMAGPART_EXPR, arg, 1);
3527 real = build_unary_op (EXPR_LOCATION (arg), code, real, 1);
3528 if (real == error_mark_node || imag == error_mark_node)
3529 return error_mark_node;
3530 ret = build2 (COMPLEX_EXPR, TREE_TYPE (arg),
3531 real, imag);
3532 goto return_build_unary_op;
3533 }
3534
3535 /* Report invalid types. */
3536
3537 if (typecode != POINTER_TYPE && typecode != FIXED_POINT_TYPE
3538 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
3539 {
3540 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3541 error_at (location, "wrong type argument to increment");
3542 else
3543 error_at (location, "wrong type argument to decrement");
3544
3545 return error_mark_node;
3546 }
3547
3548 {
3549 tree inc;
3550
3551 argtype = TREE_TYPE (arg);
3552
3553 /* Compute the increment. */
3554
3555 if (typecode == POINTER_TYPE)
3556 {
3557 /* If pointer target is an undefined struct,
3558 we just cannot know how to do the arithmetic. */
3559 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (argtype)))
3560 {
3561 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3562 error_at (location,
3563 "increment of pointer to unknown structure");
3564 else
3565 error_at (location,
3566 "decrement of pointer to unknown structure");
3567 }
3568 else if (TREE_CODE (TREE_TYPE (argtype)) == FUNCTION_TYPE
3569 || TREE_CODE (TREE_TYPE (argtype)) == VOID_TYPE)
3570 {
3571 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3572 pedwarn (location, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
3573 "wrong type argument to increment");
3574 else
3575 pedwarn (location, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
3576 "wrong type argument to decrement");
3577 }
3578
3579 inc = c_size_in_bytes (TREE_TYPE (argtype));
3580 inc = fold_convert_loc (location, sizetype, inc);
3581 }
3582 else if (FRACT_MODE_P (TYPE_MODE (argtype)))
3583 {
3584 /* For signed fract types, we invert ++ to -- or
3585 -- to ++, and change inc from 1 to -1, because
3586 it is not possible to represent 1 in signed fract constants.
3587 For unsigned fract types, the result always overflows and
3588 we get an undefined (original) or the maximum value. */
3589 if (code == PREINCREMENT_EXPR)
3590 code = PREDECREMENT_EXPR;
3591 else if (code == PREDECREMENT_EXPR)
3592 code = PREINCREMENT_EXPR;
3593 else if (code == POSTINCREMENT_EXPR)
3594 code = POSTDECREMENT_EXPR;
3595 else /* code == POSTDECREMENT_EXPR */
3596 code = POSTINCREMENT_EXPR;
3597
3598 inc = integer_minus_one_node;
3599 inc = convert (argtype, inc);
3600 }
3601 else
3602 {
3603 inc = integer_one_node;
3604 inc = convert (argtype, inc);
3605 }
3606
3607 /* Report a read-only lvalue. */
3608 if (TYPE_READONLY (argtype))
3609 {
3610 readonly_error (arg,
3611 ((code == PREINCREMENT_EXPR
3612 || code == POSTINCREMENT_EXPR)
3613 ? lv_increment : lv_decrement));
3614 return error_mark_node;
3615 }
3616 else if (TREE_READONLY (arg))
3617 readonly_warning (arg,
3618 ((code == PREINCREMENT_EXPR
3619 || code == POSTINCREMENT_EXPR)
3620 ? lv_increment : lv_decrement));
3621
3622 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
3623 val = boolean_increment (code, arg);
3624 else
3625 val = build2 (code, TREE_TYPE (arg), arg, inc);
3626 TREE_SIDE_EFFECTS (val) = 1;
3627 if (TREE_CODE (val) != code)
3628 TREE_NO_WARNING (val) = 1;
3629 ret = val;
3630 goto return_build_unary_op;
3631 }
3632
3633 case ADDR_EXPR:
3634 /* Note that this operation never does default_conversion. */
3635
3636 /* The operand of unary '&' must be an lvalue (which excludes
3637 expressions of type void), or, in C99, the result of a [] or
3638 unary '*' operator. */
3639 if (VOID_TYPE_P (TREE_TYPE (arg))
3640 && TYPE_QUALS (TREE_TYPE (arg)) == TYPE_UNQUALIFIED
3641 && (TREE_CODE (arg) != INDIRECT_REF
3642 || !flag_isoc99))
3643 pedwarn (location, 0, "taking address of expression of type %<void%>");
3644
3645 /* Let &* cancel out to simplify resulting code. */
3646 if (TREE_CODE (arg) == INDIRECT_REF)
3647 {
3648 /* Don't let this be an lvalue. */
3649 if (lvalue_p (TREE_OPERAND (arg, 0)))
3650 return non_lvalue_loc (location, TREE_OPERAND (arg, 0));
3651 ret = TREE_OPERAND (arg, 0);
3652 goto return_build_unary_op;
3653 }
3654
3655 /* For &x[y], return x+y */
3656 if (TREE_CODE (arg) == ARRAY_REF)
3657 {
3658 tree op0 = TREE_OPERAND (arg, 0);
3659 if (!c_mark_addressable (op0))
3660 return error_mark_node;
3661 return build_binary_op (location, PLUS_EXPR,
3662 (TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE
3663 ? array_to_pointer_conversion (location,
3664 op0)
3665 : op0),
3666 TREE_OPERAND (arg, 1), 1);
3667 }
3668
3669 /* Anything not already handled and not a true memory reference
3670 or a non-lvalue array is an error. */
3671 else if (typecode != FUNCTION_TYPE && !flag
3672 && !lvalue_or_else (arg, lv_addressof))
3673 return error_mark_node;
3674
3675 /* Move address operations inside C_MAYBE_CONST_EXPR to simplify
3676 folding later. */
3677 if (TREE_CODE (arg) == C_MAYBE_CONST_EXPR)
3678 {
3679 tree inner = build_unary_op (location, code,
3680 C_MAYBE_CONST_EXPR_EXPR (arg), flag);
3681 ret = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (inner),
3682 C_MAYBE_CONST_EXPR_PRE (arg), inner);
3683 gcc_assert (!C_MAYBE_CONST_EXPR_INT_OPERANDS (arg));
3684 C_MAYBE_CONST_EXPR_NON_CONST (ret)
3685 = C_MAYBE_CONST_EXPR_NON_CONST (arg);
3686 goto return_build_unary_op;
3687 }
3688
3689 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3690 argtype = TREE_TYPE (arg);
3691
3692 /* If the lvalue is const or volatile, merge that into the type
3693 to which the address will point. Note that you can't get a
3694 restricted pointer by taking the address of something, so we
3695 only have to deal with `const' and `volatile' here. */
3696 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
3697 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
3698 argtype = c_build_type_variant (argtype,
3699 TREE_READONLY (arg),
3700 TREE_THIS_VOLATILE (arg));
3701
3702 if (!c_mark_addressable (arg))
3703 return error_mark_node;
3704
3705 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
3706 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
3707
3708 argtype = build_pointer_type (argtype);
3709
3710 /* ??? Cope with user tricks that amount to offsetof. Delete this
3711 when we have proper support for integer constant expressions. */
3712 val = get_base_address (arg);
3713 if (val && TREE_CODE (val) == INDIRECT_REF
3714 && TREE_CONSTANT (TREE_OPERAND (val, 0)))
3715 {
3716 tree op0 = fold_convert_loc (location, sizetype,
3717 fold_offsetof (arg, val)), op1;
3718
3719 op1 = fold_convert_loc (location, argtype, TREE_OPERAND (val, 0));
3720 ret = fold_build2_loc (location, POINTER_PLUS_EXPR, argtype, op1, op0);
3721 goto return_build_unary_op;
3722 }
3723
3724 val = build1 (ADDR_EXPR, argtype, arg);
3725
3726 ret = val;
3727 goto return_build_unary_op;
3728
3729 default:
3730 gcc_unreachable ();
3731 }
3732
3733 if (argtype == 0)
3734 argtype = TREE_TYPE (arg);
3735 if (TREE_CODE (arg) == INTEGER_CST)
3736 ret = (require_constant_value
3737 ? fold_build1_initializer_loc (location, code, argtype, arg)
3738 : fold_build1_loc (location, code, argtype, arg));
3739 else
3740 ret = build1 (code, argtype, arg);
3741 return_build_unary_op:
3742 gcc_assert (ret != error_mark_node);
3743 if (TREE_CODE (ret) == INTEGER_CST && !TREE_OVERFLOW (ret)
3744 && !(TREE_CODE (xarg) == INTEGER_CST && !TREE_OVERFLOW (xarg)))
3745 ret = build1 (NOP_EXPR, TREE_TYPE (ret), ret);
3746 else if (TREE_CODE (ret) != INTEGER_CST && int_operands)
3747 ret = note_integer_operands (ret);
3748 if (eptype)
3749 ret = build1 (EXCESS_PRECISION_EXPR, eptype, ret);
3750 protected_set_expr_location (ret, location);
3751 return ret;
3752 }
3753
3754 /* Return nonzero if REF is an lvalue valid for this language.
3755 Lvalues can be assigned, unless their type has TYPE_READONLY.
3756 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
3757
3758 bool
3759 lvalue_p (const_tree ref)
3760 {
3761 const enum tree_code code = TREE_CODE (ref);
3762
3763 switch (code)
3764 {
3765 case REALPART_EXPR:
3766 case IMAGPART_EXPR:
3767 case COMPONENT_REF:
3768 return lvalue_p (TREE_OPERAND (ref, 0));
3769
3770 case C_MAYBE_CONST_EXPR:
3771 return lvalue_p (TREE_OPERAND (ref, 1));
3772
3773 case COMPOUND_LITERAL_EXPR:
3774 case STRING_CST:
3775 return 1;
3776
3777 case INDIRECT_REF:
3778 case ARRAY_REF:
3779 case VAR_DECL:
3780 case PARM_DECL:
3781 case RESULT_DECL:
3782 case ERROR_MARK:
3783 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3784 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3785
3786 case BIND_EXPR:
3787 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3788
3789 default:
3790 return 0;
3791 }
3792 }
3793 \f
3794 /* Give an error for storing in something that is 'const'. */
3795
3796 static void
3797 readonly_error (tree arg, enum lvalue_use use)
3798 {
3799 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement
3800 || use == lv_asm);
3801 /* Using this macro rather than (for example) arrays of messages
3802 ensures that all the format strings are checked at compile
3803 time. */
3804 #define READONLY_MSG(A, I, D, AS) (use == lv_assign ? (A) \
3805 : (use == lv_increment ? (I) \
3806 : (use == lv_decrement ? (D) : (AS))))
3807 if (TREE_CODE (arg) == COMPONENT_REF)
3808 {
3809 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3810 readonly_error (TREE_OPERAND (arg, 0), use);
3811 else
3812 error (READONLY_MSG (G_("assignment of read-only member %qD"),
3813 G_("increment of read-only member %qD"),
3814 G_("decrement of read-only member %qD"),
3815 G_("read-only member %qD used as %<asm%> output")),
3816 TREE_OPERAND (arg, 1));
3817 }
3818 else if (TREE_CODE (arg) == VAR_DECL)
3819 error (READONLY_MSG (G_("assignment of read-only variable %qD"),
3820 G_("increment of read-only variable %qD"),
3821 G_("decrement of read-only variable %qD"),
3822 G_("read-only variable %qD used as %<asm%> output")),
3823 arg);
3824 else
3825 error (READONLY_MSG (G_("assignment of read-only location %qE"),
3826 G_("increment of read-only location %qE"),
3827 G_("decrement of read-only location %qE"),
3828 G_("read-only location %qE used as %<asm%> output")),
3829 arg);
3830 }
3831
3832 /* Give a warning for storing in something that is read-only in GCC
3833 terms but not const in ISO C terms. */
3834
3835 static void
3836 readonly_warning (tree arg, enum lvalue_use use)
3837 {
3838 switch (use)
3839 {
3840 case lv_assign:
3841 warning (0, "assignment of read-only location %qE", arg);
3842 break;
3843 case lv_increment:
3844 warning (0, "increment of read-only location %qE", arg);
3845 break;
3846 case lv_decrement:
3847 warning (0, "decrement of read-only location %qE", arg);
3848 break;
3849 default:
3850 gcc_unreachable ();
3851 }
3852 return;
3853 }
3854
3855
3856 /* Return nonzero if REF is an lvalue valid for this language;
3857 otherwise, print an error message and return zero. USE says
3858 how the lvalue is being used and so selects the error message. */
3859
3860 static int
3861 lvalue_or_else (const_tree ref, enum lvalue_use use)
3862 {
3863 int win = lvalue_p (ref);
3864
3865 if (!win)
3866 lvalue_error (use);
3867
3868 return win;
3869 }
3870 \f
3871 /* Mark EXP saying that we need to be able to take the
3872 address of it; it should not be allocated in a register.
3873 Returns true if successful. */
3874
3875 bool
3876 c_mark_addressable (tree exp)
3877 {
3878 tree x = exp;
3879
3880 while (1)
3881 switch (TREE_CODE (x))
3882 {
3883 case COMPONENT_REF:
3884 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3885 {
3886 error
3887 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
3888 return false;
3889 }
3890
3891 /* ... fall through ... */
3892
3893 case ADDR_EXPR:
3894 case ARRAY_REF:
3895 case REALPART_EXPR:
3896 case IMAGPART_EXPR:
3897 x = TREE_OPERAND (x, 0);
3898 break;
3899
3900 case COMPOUND_LITERAL_EXPR:
3901 case CONSTRUCTOR:
3902 TREE_ADDRESSABLE (x) = 1;
3903 return true;
3904
3905 case VAR_DECL:
3906 case CONST_DECL:
3907 case PARM_DECL:
3908 case RESULT_DECL:
3909 if (C_DECL_REGISTER (x)
3910 && DECL_NONLOCAL (x))
3911 {
3912 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3913 {
3914 error
3915 ("global register variable %qD used in nested function", x);
3916 return false;
3917 }
3918 pedwarn (input_location, 0, "register variable %qD used in nested function", x);
3919 }
3920 else if (C_DECL_REGISTER (x))
3921 {
3922 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3923 error ("address of global register variable %qD requested", x);
3924 else
3925 error ("address of register variable %qD requested", x);
3926 return false;
3927 }
3928
3929 /* drops in */
3930 case FUNCTION_DECL:
3931 TREE_ADDRESSABLE (x) = 1;
3932 /* drops out */
3933 default:
3934 return true;
3935 }
3936 }
3937 \f
3938 /* Convert EXPR to TYPE, warning about conversion problems with
3939 constants. SEMANTIC_TYPE is the type this conversion would use
3940 without excess precision. If SEMANTIC_TYPE is NULL, this function
3941 is equivalent to convert_and_check. This function is a wrapper that
3942 handles conversions that may be different than
3943 the usual ones because of excess precision. */
3944
3945 static tree
3946 ep_convert_and_check (tree type, tree expr, tree semantic_type)
3947 {
3948 if (TREE_TYPE (expr) == type)
3949 return expr;
3950
3951 if (!semantic_type)
3952 return convert_and_check (type, expr);
3953
3954 if (TREE_CODE (TREE_TYPE (expr)) == INTEGER_TYPE
3955 && TREE_TYPE (expr) != semantic_type)
3956 {
3957 /* For integers, we need to check the real conversion, not
3958 the conversion to the excess precision type. */
3959 expr = convert_and_check (semantic_type, expr);
3960 }
3961 /* Result type is the excess precision type, which should be
3962 large enough, so do not check. */
3963 return convert (type, expr);
3964 }
3965
3966 /* Build and return a conditional expression IFEXP ? OP1 : OP2. If
3967 IFEXP_BCP then the condition is a call to __builtin_constant_p, and
3968 if folded to an integer constant then the unselected half may
3969 contain arbitrary operations not normally permitted in constant
3970 expressions. Set the location of the expression to LOC. */
3971
3972 tree
3973 build_conditional_expr (location_t colon_loc, tree ifexp, bool ifexp_bcp,
3974 tree op1, tree op1_original_type, tree op2,
3975 tree op2_original_type)
3976 {
3977 tree type1;
3978 tree type2;
3979 enum tree_code code1;
3980 enum tree_code code2;
3981 tree result_type = NULL;
3982 tree semantic_result_type = NULL;
3983 tree orig_op1 = op1, orig_op2 = op2;
3984 bool int_const, op1_int_operands, op2_int_operands, int_operands;
3985 bool ifexp_int_operands;
3986 tree ret;
3987 bool objc_ok;
3988
3989 op1_int_operands = EXPR_INT_CONST_OPERANDS (orig_op1);
3990 if (op1_int_operands)
3991 op1 = remove_c_maybe_const_expr (op1);
3992 op2_int_operands = EXPR_INT_CONST_OPERANDS (orig_op2);
3993 if (op2_int_operands)
3994 op2 = remove_c_maybe_const_expr (op2);
3995 ifexp_int_operands = EXPR_INT_CONST_OPERANDS (ifexp);
3996 if (ifexp_int_operands)
3997 ifexp = remove_c_maybe_const_expr (ifexp);
3998
3999 /* Promote both alternatives. */
4000
4001 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
4002 op1 = default_conversion (op1);
4003 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
4004 op2 = default_conversion (op2);
4005
4006 if (TREE_CODE (ifexp) == ERROR_MARK
4007 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
4008 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
4009 return error_mark_node;
4010
4011 type1 = TREE_TYPE (op1);
4012 code1 = TREE_CODE (type1);
4013 type2 = TREE_TYPE (op2);
4014 code2 = TREE_CODE (type2);
4015
4016 /* C90 does not permit non-lvalue arrays in conditional expressions.
4017 In C99 they will be pointers by now. */
4018 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
4019 {
4020 error_at (colon_loc, "non-lvalue array in conditional expression");
4021 return error_mark_node;
4022 }
4023
4024 objc_ok = objc_compare_types (type1, type2, -3, NULL_TREE);
4025
4026 if ((TREE_CODE (op1) == EXCESS_PRECISION_EXPR
4027 || TREE_CODE (op2) == EXCESS_PRECISION_EXPR)
4028 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
4029 || code1 == COMPLEX_TYPE)
4030 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
4031 || code2 == COMPLEX_TYPE))
4032 {
4033 semantic_result_type = c_common_type (type1, type2);
4034 if (TREE_CODE (op1) == EXCESS_PRECISION_EXPR)
4035 {
4036 op1 = TREE_OPERAND (op1, 0);
4037 type1 = TREE_TYPE (op1);
4038 gcc_assert (TREE_CODE (type1) == code1);
4039 }
4040 if (TREE_CODE (op2) == EXCESS_PRECISION_EXPR)
4041 {
4042 op2 = TREE_OPERAND (op2, 0);
4043 type2 = TREE_TYPE (op2);
4044 gcc_assert (TREE_CODE (type2) == code2);
4045 }
4046 }
4047
4048 if (warn_cxx_compat)
4049 {
4050 tree t1 = op1_original_type ? op1_original_type : TREE_TYPE (orig_op1);
4051 tree t2 = op2_original_type ? op2_original_type : TREE_TYPE (orig_op2);
4052
4053 if (TREE_CODE (t1) == ENUMERAL_TYPE
4054 && TREE_CODE (t2) == ENUMERAL_TYPE
4055 && TYPE_MAIN_VARIANT (t1) != TYPE_MAIN_VARIANT (t2))
4056 warning_at (colon_loc, OPT_Wc___compat,
4057 ("different enum types in conditional is "
4058 "invalid in C++: %qT vs %qT"),
4059 t1, t2);
4060 }
4061
4062 /* Quickly detect the usual case where op1 and op2 have the same type
4063 after promotion. */
4064 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
4065 {
4066 if (type1 == type2)
4067 result_type = type1;
4068 else
4069 result_type = TYPE_MAIN_VARIANT (type1);
4070 }
4071 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
4072 || code1 == COMPLEX_TYPE)
4073 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
4074 || code2 == COMPLEX_TYPE))
4075 {
4076 result_type = c_common_type (type1, type2);
4077
4078 /* If -Wsign-compare, warn here if type1 and type2 have
4079 different signedness. We'll promote the signed to unsigned
4080 and later code won't know it used to be different.
4081 Do this check on the original types, so that explicit casts
4082 will be considered, but default promotions won't. */
4083 if (c_inhibit_evaluation_warnings == 0)
4084 {
4085 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
4086 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
4087
4088 if (unsigned_op1 ^ unsigned_op2)
4089 {
4090 bool ovf;
4091
4092 /* Do not warn if the result type is signed, since the
4093 signed type will only be chosen if it can represent
4094 all the values of the unsigned type. */
4095 if (!TYPE_UNSIGNED (result_type))
4096 /* OK */;
4097 else
4098 {
4099 bool op1_maybe_const = true;
4100 bool op2_maybe_const = true;
4101
4102 /* Do not warn if the signed quantity is an
4103 unsuffixed integer literal (or some static
4104 constant expression involving such literals) and
4105 it is non-negative. This warning requires the
4106 operands to be folded for best results, so do
4107 that folding in this case even without
4108 warn_sign_compare to avoid warning options
4109 possibly affecting code generation. */
4110 c_inhibit_evaluation_warnings
4111 += (ifexp == truthvalue_false_node);
4112 op1 = c_fully_fold (op1, require_constant_value,
4113 &op1_maybe_const);
4114 c_inhibit_evaluation_warnings
4115 -= (ifexp == truthvalue_false_node);
4116
4117 c_inhibit_evaluation_warnings
4118 += (ifexp == truthvalue_true_node);
4119 op2 = c_fully_fold (op2, require_constant_value,
4120 &op2_maybe_const);
4121 c_inhibit_evaluation_warnings
4122 -= (ifexp == truthvalue_true_node);
4123
4124 if (warn_sign_compare)
4125 {
4126 if ((unsigned_op2
4127 && tree_expr_nonnegative_warnv_p (op1, &ovf))
4128 || (unsigned_op1
4129 && tree_expr_nonnegative_warnv_p (op2, &ovf)))
4130 /* OK */;
4131 else
4132 warning_at (colon_loc, OPT_Wsign_compare,
4133 ("signed and unsigned type in "
4134 "conditional expression"));
4135 }
4136 if (!op1_maybe_const || TREE_CODE (op1) != INTEGER_CST)
4137 op1 = c_wrap_maybe_const (op1, !op1_maybe_const);
4138 if (!op2_maybe_const || TREE_CODE (op2) != INTEGER_CST)
4139 op2 = c_wrap_maybe_const (op2, !op2_maybe_const);
4140 }
4141 }
4142 }
4143 }
4144 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
4145 {
4146 if (code1 != VOID_TYPE || code2 != VOID_TYPE)
4147 pedwarn (colon_loc, OPT_pedantic,
4148 "ISO C forbids conditional expr with only one void side");
4149 result_type = void_type_node;
4150 }
4151 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
4152 {
4153 addr_space_t as1 = TYPE_ADDR_SPACE (TREE_TYPE (type1));
4154 addr_space_t as2 = TYPE_ADDR_SPACE (TREE_TYPE (type2));
4155 addr_space_t as_common;
4156
4157 if (comp_target_types (colon_loc, type1, type2))
4158 result_type = common_pointer_type (type1, type2);
4159 else if (null_pointer_constant_p (orig_op1))
4160 result_type = type2;
4161 else if (null_pointer_constant_p (orig_op2))
4162 result_type = type1;
4163 else if (!addr_space_superset (as1, as2, &as_common))
4164 {
4165 error_at (colon_loc, "pointers to disjoint address spaces "
4166 "used in conditional expression");
4167 return error_mark_node;
4168 }
4169 else if (VOID_TYPE_P (TREE_TYPE (type1)))
4170 {
4171 if (TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
4172 pedwarn (colon_loc, OPT_pedantic,
4173 "ISO C forbids conditional expr between "
4174 "%<void *%> and function pointer");
4175 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
4176 TREE_TYPE (type2)));
4177 }
4178 else if (VOID_TYPE_P (TREE_TYPE (type2)))
4179 {
4180 if (TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
4181 pedwarn (colon_loc, OPT_pedantic,
4182 "ISO C forbids conditional expr between "
4183 "%<void *%> and function pointer");
4184 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
4185 TREE_TYPE (type1)));
4186 }
4187 else
4188 {
4189 int qual = ENCODE_QUAL_ADDR_SPACE (as_common);
4190
4191 if (!objc_ok)
4192 pedwarn (colon_loc, 0,
4193 "pointer type mismatch in conditional expression");
4194 result_type = build_pointer_type
4195 (build_qualified_type (void_type_node, qual));
4196 }
4197 }
4198 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
4199 {
4200 if (!null_pointer_constant_p (orig_op2))
4201 pedwarn (colon_loc, 0,
4202 "pointer/integer type mismatch in conditional expression");
4203 else
4204 {
4205 op2 = null_pointer_node;
4206 }
4207 result_type = type1;
4208 }
4209 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
4210 {
4211 if (!null_pointer_constant_p (orig_op1))
4212 pedwarn (colon_loc, 0,
4213 "pointer/integer type mismatch in conditional expression");
4214 else
4215 {
4216 op1 = null_pointer_node;
4217 }
4218 result_type = type2;
4219 }
4220
4221 if (!result_type)
4222 {
4223 if (flag_cond_mismatch)
4224 result_type = void_type_node;
4225 else
4226 {
4227 error_at (colon_loc, "type mismatch in conditional expression");
4228 return error_mark_node;
4229 }
4230 }
4231
4232 /* Merge const and volatile flags of the incoming types. */
4233 result_type
4234 = build_type_variant (result_type,
4235 TYPE_READONLY (type1) || TYPE_READONLY (type2),
4236 TYPE_VOLATILE (type1) || TYPE_VOLATILE (type2));
4237
4238 op1 = ep_convert_and_check (result_type, op1, semantic_result_type);
4239 op2 = ep_convert_and_check (result_type, op2, semantic_result_type);
4240
4241 if (ifexp_bcp && ifexp == truthvalue_true_node)
4242 {
4243 op2_int_operands = true;
4244 op1 = c_fully_fold (op1, require_constant_value, NULL);
4245 }
4246 if (ifexp_bcp && ifexp == truthvalue_false_node)
4247 {
4248 op1_int_operands = true;
4249 op2 = c_fully_fold (op2, require_constant_value, NULL);
4250 }
4251 int_const = int_operands = (ifexp_int_operands
4252 && op1_int_operands
4253 && op2_int_operands);
4254 if (int_operands)
4255 {
4256 int_const = ((ifexp == truthvalue_true_node
4257 && TREE_CODE (orig_op1) == INTEGER_CST
4258 && !TREE_OVERFLOW (orig_op1))
4259 || (ifexp == truthvalue_false_node
4260 && TREE_CODE (orig_op2) == INTEGER_CST
4261 && !TREE_OVERFLOW (orig_op2)));
4262 }
4263 if (int_const || (ifexp_bcp && TREE_CODE (ifexp) == INTEGER_CST))
4264 ret = fold_build3_loc (colon_loc, COND_EXPR, result_type, ifexp, op1, op2);
4265 else
4266 {
4267 ret = build3 (COND_EXPR, result_type, ifexp, op1, op2);
4268 if (int_operands)
4269 ret = note_integer_operands (ret);
4270 }
4271 if (semantic_result_type)
4272 ret = build1 (EXCESS_PRECISION_EXPR, semantic_result_type, ret);
4273
4274 protected_set_expr_location (ret, colon_loc);
4275 return ret;
4276 }
4277 \f
4278 /* Return a compound expression that performs two expressions and
4279 returns the value of the second of them.
4280
4281 LOC is the location of the COMPOUND_EXPR. */
4282
4283 tree
4284 build_compound_expr (location_t loc, tree expr1, tree expr2)
4285 {
4286 bool expr1_int_operands, expr2_int_operands;
4287 tree eptype = NULL_TREE;
4288 tree ret;
4289
4290 expr1_int_operands = EXPR_INT_CONST_OPERANDS (expr1);
4291 if (expr1_int_operands)
4292 expr1 = remove_c_maybe_const_expr (expr1);
4293 expr2_int_operands = EXPR_INT_CONST_OPERANDS (expr2);
4294 if (expr2_int_operands)
4295 expr2 = remove_c_maybe_const_expr (expr2);
4296
4297 if (TREE_CODE (expr1) == EXCESS_PRECISION_EXPR)
4298 expr1 = TREE_OPERAND (expr1, 0);
4299 if (TREE_CODE (expr2) == EXCESS_PRECISION_EXPR)
4300 {
4301 eptype = TREE_TYPE (expr2);
4302 expr2 = TREE_OPERAND (expr2, 0);
4303 }
4304
4305 if (!TREE_SIDE_EFFECTS (expr1))
4306 {
4307 /* The left-hand operand of a comma expression is like an expression
4308 statement: with -Wunused, we should warn if it doesn't have
4309 any side-effects, unless it was explicitly cast to (void). */
4310 if (warn_unused_value)
4311 {
4312 if (VOID_TYPE_P (TREE_TYPE (expr1))
4313 && CONVERT_EXPR_P (expr1))
4314 ; /* (void) a, b */
4315 else if (VOID_TYPE_P (TREE_TYPE (expr1))
4316 && TREE_CODE (expr1) == COMPOUND_EXPR
4317 && CONVERT_EXPR_P (TREE_OPERAND (expr1, 1)))
4318 ; /* (void) a, (void) b, c */
4319 else
4320 warning_at (loc, OPT_Wunused_value,
4321 "left-hand operand of comma expression has no effect");
4322 }
4323 }
4324
4325 /* With -Wunused, we should also warn if the left-hand operand does have
4326 side-effects, but computes a value which is not used. For example, in
4327 `foo() + bar(), baz()' the result of the `+' operator is not used,
4328 so we should issue a warning. */
4329 else if (warn_unused_value)
4330 warn_if_unused_value (expr1, loc);
4331
4332 if (expr2 == error_mark_node)
4333 return error_mark_node;
4334
4335 ret = build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
4336
4337 if (flag_isoc99
4338 && expr1_int_operands
4339 && expr2_int_operands)
4340 ret = note_integer_operands (ret);
4341
4342 if (eptype)
4343 ret = build1 (EXCESS_PRECISION_EXPR, eptype, ret);
4344
4345 protected_set_expr_location (ret, loc);
4346 return ret;
4347 }
4348
4349 /* Issue -Wcast-qual warnings when appropriate. TYPE is the type to
4350 which we are casting. OTYPE is the type of the expression being
4351 cast. Both TYPE and OTYPE are pointer types. -Wcast-qual appeared
4352 on the command line. Named address space qualifiers are not handled
4353 here, because they result in different warnings. */
4354
4355 static void
4356 handle_warn_cast_qual (tree type, tree otype)
4357 {
4358 tree in_type = type;
4359 tree in_otype = otype;
4360 int added = 0;
4361 int discarded = 0;
4362 bool is_const;
4363
4364 /* Check that the qualifiers on IN_TYPE are a superset of the
4365 qualifiers of IN_OTYPE. The outermost level of POINTER_TYPE
4366 nodes is uninteresting and we stop as soon as we hit a
4367 non-POINTER_TYPE node on either type. */
4368 do
4369 {
4370 in_otype = TREE_TYPE (in_otype);
4371 in_type = TREE_TYPE (in_type);
4372
4373 /* GNU C allows cv-qualified function types. 'const' means the
4374 function is very pure, 'volatile' means it can't return. We
4375 need to warn when such qualifiers are added, not when they're
4376 taken away. */
4377 if (TREE_CODE (in_otype) == FUNCTION_TYPE
4378 && TREE_CODE (in_type) == FUNCTION_TYPE)
4379 added |= (TYPE_QUALS_NO_ADDR_SPACE (in_type)
4380 & ~TYPE_QUALS_NO_ADDR_SPACE (in_otype));
4381 else
4382 discarded |= (TYPE_QUALS_NO_ADDR_SPACE (in_otype)
4383 & ~TYPE_QUALS_NO_ADDR_SPACE (in_type));
4384 }
4385 while (TREE_CODE (in_type) == POINTER_TYPE
4386 && TREE_CODE (in_otype) == POINTER_TYPE);
4387
4388 if (added)
4389 warning (OPT_Wcast_qual, "cast adds new qualifiers to function type");
4390
4391 if (discarded)
4392 /* There are qualifiers present in IN_OTYPE that are not present
4393 in IN_TYPE. */
4394 warning (OPT_Wcast_qual,
4395 "cast discards qualifiers from pointer target type");
4396
4397 if (added || discarded)
4398 return;
4399
4400 /* A cast from **T to const **T is unsafe, because it can cause a
4401 const value to be changed with no additional warning. We only
4402 issue this warning if T is the same on both sides, and we only
4403 issue the warning if there are the same number of pointers on
4404 both sides, as otherwise the cast is clearly unsafe anyhow. A
4405 cast is unsafe when a qualifier is added at one level and const
4406 is not present at all outer levels.
4407
4408 To issue this warning, we check at each level whether the cast
4409 adds new qualifiers not already seen. We don't need to special
4410 case function types, as they won't have the same
4411 TYPE_MAIN_VARIANT. */
4412
4413 if (TYPE_MAIN_VARIANT (in_type) != TYPE_MAIN_VARIANT (in_otype))
4414 return;
4415 if (TREE_CODE (TREE_TYPE (type)) != POINTER_TYPE)
4416 return;
4417
4418 in_type = type;
4419 in_otype = otype;
4420 is_const = TYPE_READONLY (TREE_TYPE (in_type));
4421 do
4422 {
4423 in_type = TREE_TYPE (in_type);
4424 in_otype = TREE_TYPE (in_otype);
4425 if ((TYPE_QUALS (in_type) &~ TYPE_QUALS (in_otype)) != 0
4426 && !is_const)
4427 {
4428 warning (OPT_Wcast_qual,
4429 ("new qualifiers in middle of multi-level non-const cast "
4430 "are unsafe"));
4431 break;
4432 }
4433 if (is_const)
4434 is_const = TYPE_READONLY (in_type);
4435 }
4436 while (TREE_CODE (in_type) == POINTER_TYPE);
4437 }
4438
4439 /* Build an expression representing a cast to type TYPE of expression EXPR.
4440 LOC is the location of the cast-- typically the open paren of the cast. */
4441
4442 tree
4443 build_c_cast (location_t loc, tree type, tree expr)
4444 {
4445 tree value;
4446
4447 if (TREE_CODE (expr) == EXCESS_PRECISION_EXPR)
4448 expr = TREE_OPERAND (expr, 0);
4449
4450 value = expr;
4451
4452 if (type == error_mark_node || expr == error_mark_node)
4453 return error_mark_node;
4454
4455 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
4456 only in <protocol> qualifications. But when constructing cast expressions,
4457 the protocols do matter and must be kept around. */
4458 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
4459 return build1 (NOP_EXPR, type, expr);
4460
4461 type = TYPE_MAIN_VARIANT (type);
4462
4463 if (TREE_CODE (type) == ARRAY_TYPE)
4464 {
4465 error_at (loc, "cast specifies array type");
4466 return error_mark_node;
4467 }
4468
4469 if (TREE_CODE (type) == FUNCTION_TYPE)
4470 {
4471 error_at (loc, "cast specifies function type");
4472 return error_mark_node;
4473 }
4474
4475 if (!VOID_TYPE_P (type))
4476 {
4477 value = require_complete_type (value);
4478 if (value == error_mark_node)
4479 return error_mark_node;
4480 }
4481
4482 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
4483 {
4484 if (TREE_CODE (type) == RECORD_TYPE
4485 || TREE_CODE (type) == UNION_TYPE)
4486 pedwarn (loc, OPT_pedantic,
4487 "ISO C forbids casting nonscalar to the same type");
4488 }
4489 else if (TREE_CODE (type) == UNION_TYPE)
4490 {
4491 tree field;
4492
4493 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
4494 if (TREE_TYPE (field) != error_mark_node
4495 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
4496 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
4497 break;
4498
4499 if (field)
4500 {
4501 tree t;
4502 bool maybe_const = true;
4503
4504 pedwarn (loc, OPT_pedantic, "ISO C forbids casts to union type");
4505 t = c_fully_fold (value, false, &maybe_const);
4506 t = build_constructor_single (type, field, t);
4507 if (!maybe_const)
4508 t = c_wrap_maybe_const (t, true);
4509 t = digest_init (loc, type, t,
4510 NULL_TREE, false, true, 0);
4511 TREE_CONSTANT (t) = TREE_CONSTANT (value);
4512 return t;
4513 }
4514 error_at (loc, "cast to union type from type not present in union");
4515 return error_mark_node;
4516 }
4517 else
4518 {
4519 tree otype, ovalue;
4520
4521 if (type == void_type_node)
4522 {
4523 tree t = build1 (CONVERT_EXPR, type, value);
4524 SET_EXPR_LOCATION (t, loc);
4525 return t;
4526 }
4527
4528 otype = TREE_TYPE (value);
4529
4530 /* Optionally warn about potentially worrisome casts. */
4531 if (warn_cast_qual
4532 && TREE_CODE (type) == POINTER_TYPE
4533 && TREE_CODE (otype) == POINTER_TYPE)
4534 handle_warn_cast_qual (type, otype);
4535
4536 /* Warn about conversions between pointers to disjoint
4537 address spaces. */
4538 if (TREE_CODE (type) == POINTER_TYPE
4539 && TREE_CODE (otype) == POINTER_TYPE
4540 && !null_pointer_constant_p (value))
4541 {
4542 addr_space_t as_to = TYPE_ADDR_SPACE (TREE_TYPE (type));
4543 addr_space_t as_from = TYPE_ADDR_SPACE (TREE_TYPE (otype));
4544 addr_space_t as_common;
4545
4546 if (!addr_space_superset (as_to, as_from, &as_common))
4547 {
4548 if (ADDR_SPACE_GENERIC_P (as_from))
4549 warning_at (loc, 0, "cast to %s address space pointer "
4550 "from disjoint generic address space pointer",
4551 c_addr_space_name (as_to));
4552
4553 else if (ADDR_SPACE_GENERIC_P (as_to))
4554 warning_at (loc, 0, "cast to generic address space pointer "
4555 "from disjoint %s address space pointer",
4556 c_addr_space_name (as_from));
4557
4558 else
4559 warning_at (loc, 0, "cast to %s address space pointer "
4560 "from disjoint %s address space pointer",
4561 c_addr_space_name (as_to),
4562 c_addr_space_name (as_from));
4563 }
4564 }
4565
4566 /* Warn about possible alignment problems. */
4567 if (STRICT_ALIGNMENT
4568 && TREE_CODE (type) == POINTER_TYPE
4569 && TREE_CODE (otype) == POINTER_TYPE
4570 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
4571 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
4572 /* Don't warn about opaque types, where the actual alignment
4573 restriction is unknown. */
4574 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
4575 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
4576 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
4577 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
4578 warning_at (loc, OPT_Wcast_align,
4579 "cast increases required alignment of target type");
4580
4581 if (TREE_CODE (type) == INTEGER_TYPE
4582 && TREE_CODE (otype) == POINTER_TYPE
4583 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
4584 /* Unlike conversion of integers to pointers, where the
4585 warning is disabled for converting constants because
4586 of cases such as SIG_*, warn about converting constant
4587 pointers to integers. In some cases it may cause unwanted
4588 sign extension, and a warning is appropriate. */
4589 warning_at (loc, OPT_Wpointer_to_int_cast,
4590 "cast from pointer to integer of different size");
4591
4592 if (TREE_CODE (value) == CALL_EXPR
4593 && TREE_CODE (type) != TREE_CODE (otype))
4594 warning_at (loc, OPT_Wbad_function_cast,
4595 "cast from function call of type %qT "
4596 "to non-matching type %qT", otype, type);
4597
4598 if (TREE_CODE (type) == POINTER_TYPE
4599 && TREE_CODE (otype) == INTEGER_TYPE
4600 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
4601 /* Don't warn about converting any constant. */
4602 && !TREE_CONSTANT (value))
4603 warning_at (loc,
4604 OPT_Wint_to_pointer_cast, "cast to pointer from integer "
4605 "of different size");
4606
4607 if (warn_strict_aliasing <= 2)
4608 strict_aliasing_warning (otype, type, expr);
4609
4610 /* If pedantic, warn for conversions between function and object
4611 pointer types, except for converting a null pointer constant
4612 to function pointer type. */
4613 if (pedantic
4614 && TREE_CODE (type) == POINTER_TYPE
4615 && TREE_CODE (otype) == POINTER_TYPE
4616 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
4617 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
4618 pedwarn (loc, OPT_pedantic, "ISO C forbids "
4619 "conversion of function pointer to object pointer type");
4620
4621 if (pedantic
4622 && TREE_CODE (type) == POINTER_TYPE
4623 && TREE_CODE (otype) == POINTER_TYPE
4624 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
4625 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
4626 && !null_pointer_constant_p (value))
4627 pedwarn (loc, OPT_pedantic, "ISO C forbids "
4628 "conversion of object pointer to function pointer type");
4629
4630 ovalue = value;
4631 value = convert (type, value);
4632
4633 /* Ignore any integer overflow caused by the cast. */
4634 if (TREE_CODE (value) == INTEGER_CST && !FLOAT_TYPE_P (otype))
4635 {
4636 if (CONSTANT_CLASS_P (ovalue) && TREE_OVERFLOW (ovalue))
4637 {
4638 if (!TREE_OVERFLOW (value))
4639 {
4640 /* Avoid clobbering a shared constant. */
4641 value = copy_node (value);
4642 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
4643 }
4644 }
4645 else if (TREE_OVERFLOW (value))
4646 /* Reset VALUE's overflow flags, ensuring constant sharing. */
4647 value = build_int_cst_wide (TREE_TYPE (value),
4648 TREE_INT_CST_LOW (value),
4649 TREE_INT_CST_HIGH (value));
4650 }
4651 }
4652
4653 /* Don't let a cast be an lvalue. */
4654 if (value == expr)
4655 value = non_lvalue_loc (loc, value);
4656
4657 /* Don't allow the results of casting to floating-point or complex
4658 types be confused with actual constants, or casts involving
4659 integer and pointer types other than direct integer-to-integer
4660 and integer-to-pointer be confused with integer constant
4661 expressions and null pointer constants. */
4662 if (TREE_CODE (value) == REAL_CST
4663 || TREE_CODE (value) == COMPLEX_CST
4664 || (TREE_CODE (value) == INTEGER_CST
4665 && !((TREE_CODE (expr) == INTEGER_CST
4666 && INTEGRAL_TYPE_P (TREE_TYPE (expr)))
4667 || TREE_CODE (expr) == REAL_CST
4668 || TREE_CODE (expr) == COMPLEX_CST)))
4669 value = build1 (NOP_EXPR, type, value);
4670
4671 if (CAN_HAVE_LOCATION_P (value))
4672 SET_EXPR_LOCATION (value, loc);
4673 return value;
4674 }
4675
4676 /* Interpret a cast of expression EXPR to type TYPE. LOC is the
4677 location of the open paren of the cast, or the position of the cast
4678 expr. */
4679 tree
4680 c_cast_expr (location_t loc, struct c_type_name *type_name, tree expr)
4681 {
4682 tree type;
4683 tree type_expr = NULL_TREE;
4684 bool type_expr_const = true;
4685 tree ret;
4686 int saved_wsp = warn_strict_prototypes;
4687
4688 /* This avoids warnings about unprototyped casts on
4689 integers. E.g. "#define SIG_DFL (void(*)())0". */
4690 if (TREE_CODE (expr) == INTEGER_CST)
4691 warn_strict_prototypes = 0;
4692 type = groktypename (type_name, &type_expr, &type_expr_const);
4693 warn_strict_prototypes = saved_wsp;
4694
4695 ret = build_c_cast (loc, type, expr);
4696 if (type_expr)
4697 {
4698 ret = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (ret), type_expr, ret);
4699 C_MAYBE_CONST_EXPR_NON_CONST (ret) = !type_expr_const;
4700 SET_EXPR_LOCATION (ret, loc);
4701 }
4702
4703 if (CAN_HAVE_LOCATION_P (ret) && !EXPR_HAS_LOCATION (ret))
4704 SET_EXPR_LOCATION (ret, loc);
4705
4706 /* C++ does not permits types to be defined in a cast. */
4707 if (warn_cxx_compat && type_name->specs->tag_defined_p)
4708 warning_at (loc, OPT_Wc___compat,
4709 "defining a type in a cast is invalid in C++");
4710
4711 return ret;
4712 }
4713 \f
4714 /* Build an assignment expression of lvalue LHS from value RHS.
4715 If LHS_ORIGTYPE is not NULL, it is the original type of LHS, which
4716 may differ from TREE_TYPE (LHS) for an enum bitfield.
4717 MODIFYCODE is the code for a binary operator that we use
4718 to combine the old value of LHS with RHS to get the new value.
4719 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
4720 If RHS_ORIGTYPE is not NULL_TREE, it is the original type of RHS,
4721 which may differ from TREE_TYPE (RHS) for an enum value.
4722
4723 LOCATION is the location of the MODIFYCODE operator.
4724 RHS_LOC is the location of the RHS. */
4725
4726 tree
4727 build_modify_expr (location_t location, tree lhs, tree lhs_origtype,
4728 enum tree_code modifycode,
4729 location_t rhs_loc, tree rhs, tree rhs_origtype)
4730 {
4731 tree result;
4732 tree newrhs;
4733 tree rhs_semantic_type = NULL_TREE;
4734 tree lhstype = TREE_TYPE (lhs);
4735 tree olhstype = lhstype;
4736 bool npc;
4737
4738 /* Types that aren't fully specified cannot be used in assignments. */
4739 lhs = require_complete_type (lhs);
4740
4741 /* Avoid duplicate error messages from operands that had errors. */
4742 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
4743 return error_mark_node;
4744
4745 if (!lvalue_or_else (lhs, lv_assign))
4746 return error_mark_node;
4747
4748 if (TREE_CODE (rhs) == EXCESS_PRECISION_EXPR)
4749 {
4750 rhs_semantic_type = TREE_TYPE (rhs);
4751 rhs = TREE_OPERAND (rhs, 0);
4752 }
4753
4754 newrhs = rhs;
4755
4756 if (TREE_CODE (lhs) == C_MAYBE_CONST_EXPR)
4757 {
4758 tree inner = build_modify_expr (location, C_MAYBE_CONST_EXPR_EXPR (lhs),
4759 lhs_origtype, modifycode, rhs_loc, rhs,
4760 rhs_origtype);
4761 if (inner == error_mark_node)
4762 return error_mark_node;
4763 result = build2 (C_MAYBE_CONST_EXPR, TREE_TYPE (inner),
4764 C_MAYBE_CONST_EXPR_PRE (lhs), inner);
4765 gcc_assert (!C_MAYBE_CONST_EXPR_INT_OPERANDS (lhs));
4766 C_MAYBE_CONST_EXPR_NON_CONST (result) = 1;
4767 protected_set_expr_location (result, location);
4768 return result;
4769 }
4770
4771 /* If a binary op has been requested, combine the old LHS value with the RHS
4772 producing the value we should actually store into the LHS. */
4773
4774 if (modifycode != NOP_EXPR)
4775 {
4776 lhs = c_fully_fold (lhs, false, NULL);
4777 lhs = stabilize_reference (lhs);
4778 newrhs = build_binary_op (location,
4779 modifycode, lhs, rhs, 1);
4780
4781 /* The original type of the right hand side is no longer
4782 meaningful. */
4783 rhs_origtype = NULL_TREE;
4784 }
4785
4786 /* Give an error for storing in something that is 'const'. */
4787
4788 if (TYPE_READONLY (lhstype)
4789 || ((TREE_CODE (lhstype) == RECORD_TYPE
4790 || TREE_CODE (lhstype) == UNION_TYPE)
4791 && C_TYPE_FIELDS_READONLY (lhstype)))
4792 {
4793 readonly_error (lhs, lv_assign);
4794 return error_mark_node;
4795 }
4796 else if (TREE_READONLY (lhs))
4797 readonly_warning (lhs, lv_assign);
4798
4799 /* If storing into a structure or union member,
4800 it has probably been given type `int'.
4801 Compute the type that would go with
4802 the actual amount of storage the member occupies. */
4803
4804 if (TREE_CODE (lhs) == COMPONENT_REF
4805 && (TREE_CODE (lhstype) == INTEGER_TYPE
4806 || TREE_CODE (lhstype) == BOOLEAN_TYPE
4807 || TREE_CODE (lhstype) == REAL_TYPE
4808 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
4809 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
4810
4811 /* If storing in a field that is in actuality a short or narrower than one,
4812 we must store in the field in its actual type. */
4813
4814 if (lhstype != TREE_TYPE (lhs))
4815 {
4816 lhs = copy_node (lhs);
4817 TREE_TYPE (lhs) = lhstype;
4818 }
4819
4820 /* Issue -Wc++-compat warnings about an assignment to an enum type
4821 when LHS does not have its original type. This happens for,
4822 e.g., an enum bitfield in a struct. */
4823 if (warn_cxx_compat
4824 && lhs_origtype != NULL_TREE
4825 && lhs_origtype != lhstype
4826 && TREE_CODE (lhs_origtype) == ENUMERAL_TYPE)
4827 {
4828 tree checktype = (rhs_origtype != NULL_TREE
4829 ? rhs_origtype
4830 : TREE_TYPE (rhs));
4831 if (checktype != error_mark_node
4832 && TYPE_MAIN_VARIANT (checktype) != TYPE_MAIN_VARIANT (lhs_origtype))
4833 warning_at (location, OPT_Wc___compat,
4834 "enum conversion in assignment is invalid in C++");
4835 }
4836
4837 /* Convert new value to destination type. Fold it first, then
4838 restore any excess precision information, for the sake of
4839 conversion warnings. */
4840
4841 npc = null_pointer_constant_p (newrhs);
4842 newrhs = c_fully_fold (newrhs, false, NULL);
4843 if (rhs_semantic_type)
4844 newrhs = build1 (EXCESS_PRECISION_EXPR, rhs_semantic_type, newrhs);
4845 newrhs = convert_for_assignment (location, lhstype, newrhs, rhs_origtype,
4846 ic_assign, npc, NULL_TREE, NULL_TREE, 0);
4847 if (TREE_CODE (newrhs) == ERROR_MARK)
4848 return error_mark_node;
4849
4850 /* Emit ObjC write barrier, if necessary. */
4851 if (c_dialect_objc () && flag_objc_gc)
4852 {
4853 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
4854 if (result)
4855 {
4856 protected_set_expr_location (result, location);
4857 return result;
4858 }
4859 }
4860
4861 /* Scan operands. */
4862
4863 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
4864 TREE_SIDE_EFFECTS (result) = 1;
4865 protected_set_expr_location (result, location);
4866
4867 /* If we got the LHS in a different type for storing in,
4868 convert the result back to the nominal type of LHS
4869 so that the value we return always has the same type
4870 as the LHS argument. */
4871
4872 if (olhstype == TREE_TYPE (result))
4873 return result;
4874
4875 result = convert_for_assignment (location, olhstype, result, rhs_origtype,
4876 ic_assign, false, NULL_TREE, NULL_TREE, 0);
4877 protected_set_expr_location (result, location);
4878 return result;
4879 }
4880 \f
4881 /* Convert value RHS to type TYPE as preparation for an assignment to
4882 an lvalue of type TYPE. If ORIGTYPE is not NULL_TREE, it is the
4883 original type of RHS; this differs from TREE_TYPE (RHS) for enum
4884 types. NULL_POINTER_CONSTANT says whether RHS was a null pointer
4885 constant before any folding.
4886 The real work of conversion is done by `convert'.
4887 The purpose of this function is to generate error messages
4888 for assignments that are not allowed in C.
4889 ERRTYPE says whether it is argument passing, assignment,
4890 initialization or return.
4891
4892 LOCATION is the location of the RHS.
4893 FUNCTION is a tree for the function being called.
4894 PARMNUM is the number of the argument, for printing in error messages. */
4895
4896 static tree
4897 convert_for_assignment (location_t location, tree type, tree rhs,
4898 tree origtype, enum impl_conv errtype,
4899 bool null_pointer_constant, tree fundecl,
4900 tree function, int parmnum)
4901 {
4902 enum tree_code codel = TREE_CODE (type);
4903 tree orig_rhs = rhs;
4904 tree rhstype;
4905 enum tree_code coder;
4906 tree rname = NULL_TREE;
4907 bool objc_ok = false;
4908
4909 if (errtype == ic_argpass)
4910 {
4911 tree selector;
4912 /* Change pointer to function to the function itself for
4913 diagnostics. */
4914 if (TREE_CODE (function) == ADDR_EXPR
4915 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
4916 function = TREE_OPERAND (function, 0);
4917
4918 /* Handle an ObjC selector specially for diagnostics. */
4919 selector = objc_message_selector ();
4920 rname = function;
4921 if (selector && parmnum > 2)
4922 {
4923 rname = selector;
4924 parmnum -= 2;
4925 }
4926 }
4927
4928 /* This macro is used to emit diagnostics to ensure that all format
4929 strings are complete sentences, visible to gettext and checked at
4930 compile time. */
4931 #define WARN_FOR_ASSIGNMENT(LOCATION, OPT, AR, AS, IN, RE) \
4932 do { \
4933 switch (errtype) \
4934 { \
4935 case ic_argpass: \
4936 if (pedwarn (LOCATION, OPT, AR, parmnum, rname)) \
4937 inform ((fundecl && !DECL_IS_BUILTIN (fundecl)) \
4938 ? DECL_SOURCE_LOCATION (fundecl) : LOCATION, \
4939 "expected %qT but argument is of type %qT", \
4940 type, rhstype); \
4941 break; \
4942 case ic_assign: \
4943 pedwarn (LOCATION, OPT, AS); \
4944 break; \
4945 case ic_init: \
4946 pedwarn (LOCATION, OPT, IN); \
4947 break; \
4948 case ic_return: \
4949 pedwarn (LOCATION, OPT, RE); \
4950 break; \
4951 default: \
4952 gcc_unreachable (); \
4953 } \
4954 } while (0)
4955
4956 if (TREE_CODE (rhs) == EXCESS_PRECISION_EXPR)
4957 rhs = TREE_OPERAND (rhs, 0);
4958
4959 rhstype = TREE_TYPE (rhs);
4960 coder = TREE_CODE (rhstype);
4961
4962 if (coder == ERROR_MARK)
4963 return error_mark_node;
4964
4965 if (c_dialect_objc ())
4966 {
4967 int parmno;
4968
4969 switch (errtype)
4970 {
4971 case ic_return:
4972 parmno = 0;
4973 break;
4974
4975 case ic_assign:
4976 parmno = -1;
4977 break;
4978
4979 case ic_init:
4980 parmno = -2;
4981 break;
4982
4983 default:
4984 parmno = parmnum;
4985 break;
4986 }
4987
4988 objc_ok = objc_compare_types (type, rhstype, parmno, rname);
4989 }
4990
4991 if (warn_cxx_compat)
4992 {
4993 tree checktype = origtype != NULL_TREE ? origtype : rhstype;
4994 if (checktype != error_mark_node
4995 && TREE_CODE (type) == ENUMERAL_TYPE
4996 && TYPE_MAIN_VARIANT (checktype) != TYPE_MAIN_VARIANT (type))
4997 {
4998 WARN_FOR_ASSIGNMENT (input_location, OPT_Wc___compat,
4999 G_("enum conversion when passing argument "
5000 "%d of %qE is invalid in C++"),
5001 G_("enum conversion in assignment is "
5002 "invalid in C++"),
5003 G_("enum conversion in initialization is "
5004 "invalid in C++"),
5005 G_("enum conversion in return is "
5006 "invalid in C++"));
5007 }
5008 }
5009
5010 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
5011 return rhs;
5012
5013 if (coder == VOID_TYPE)
5014 {
5015 /* Except for passing an argument to an unprototyped function,
5016 this is a constraint violation. When passing an argument to
5017 an unprototyped function, it is compile-time undefined;
5018 making it a constraint in that case was rejected in
5019 DR#252. */
5020 error_at (location, "void value not ignored as it ought to be");
5021 return error_mark_node;
5022 }
5023 rhs = require_complete_type (rhs);
5024 if (rhs == error_mark_node)
5025 return error_mark_node;
5026 /* A type converts to a reference to it.
5027 This code doesn't fully support references, it's just for the
5028 special case of va_start and va_copy. */
5029 if (codel == REFERENCE_TYPE
5030 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
5031 {
5032 if (!lvalue_p (rhs))
5033 {
5034 error_at (location, "cannot pass rvalue to reference parameter");
5035 return error_mark_node;
5036 }
5037 if (!c_mark_addressable (rhs))
5038 return error_mark_node;
5039 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
5040 SET_EXPR_LOCATION (rhs, location);
5041
5042 /* We already know that these two types are compatible, but they
5043 may not be exactly identical. In fact, `TREE_TYPE (type)' is
5044 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
5045 likely to be va_list, a typedef to __builtin_va_list, which
5046 is different enough that it will cause problems later. */
5047 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
5048 {
5049 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
5050 SET_EXPR_LOCATION (rhs, location);
5051 }
5052
5053 rhs = build1 (NOP_EXPR, type, rhs);
5054 SET_EXPR_LOCATION (rhs, location);
5055 return rhs;
5056 }
5057 /* Some types can interconvert without explicit casts. */
5058 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
5059 && vector_types_convertible_p (type, TREE_TYPE (rhs), true))
5060 return convert (type, rhs);
5061 /* Arithmetic types all interconvert, and enum is treated like int. */
5062 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
5063 || codel == FIXED_POINT_TYPE
5064 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
5065 || codel == BOOLEAN_TYPE)
5066 && (coder == INTEGER_TYPE || coder == REAL_TYPE
5067 || coder == FIXED_POINT_TYPE
5068 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
5069 || coder == BOOLEAN_TYPE))
5070 {
5071 tree ret;
5072 bool save = in_late_binary_op;
5073 if (codel == BOOLEAN_TYPE)
5074 in_late_binary_op = true;
5075 ret = convert_and_check (type, orig_rhs);
5076 if (codel == BOOLEAN_TYPE)
5077 in_late_binary_op = save;
5078 return ret;
5079 }
5080
5081 /* Aggregates in different TUs might need conversion. */
5082 if ((codel == RECORD_TYPE || codel == UNION_TYPE)
5083 && codel == coder
5084 && comptypes (type, rhstype))
5085 return convert_and_check (type, rhs);
5086
5087 /* Conversion to a transparent union or record from its member types.
5088 This applies only to function arguments. */
5089 if (((codel == UNION_TYPE || codel == RECORD_TYPE)
5090 && TYPE_TRANSPARENT_AGGR (type))
5091 && errtype == ic_argpass)
5092 {
5093 tree memb, marginal_memb = NULL_TREE;
5094
5095 for (memb = TYPE_FIELDS (type); memb ; memb = TREE_CHAIN (memb))
5096 {
5097 tree memb_type = TREE_TYPE (memb);
5098
5099 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
5100 TYPE_MAIN_VARIANT (rhstype)))
5101 break;
5102
5103 if (TREE_CODE (memb_type) != POINTER_TYPE)
5104 continue;
5105
5106 if (coder == POINTER_TYPE)
5107 {
5108 tree ttl = TREE_TYPE (memb_type);
5109 tree ttr = TREE_TYPE (rhstype);
5110
5111 /* Any non-function converts to a [const][volatile] void *
5112 and vice versa; otherwise, targets must be the same.
5113 Meanwhile, the lhs target must have all the qualifiers of
5114 the rhs. */
5115 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
5116 || comp_target_types (location, memb_type, rhstype))
5117 {
5118 /* If this type won't generate any warnings, use it. */
5119 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
5120 || ((TREE_CODE (ttr) == FUNCTION_TYPE
5121 && TREE_CODE (ttl) == FUNCTION_TYPE)
5122 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
5123 == TYPE_QUALS (ttr))
5124 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
5125 == TYPE_QUALS (ttl))))
5126 break;
5127
5128 /* Keep looking for a better type, but remember this one. */
5129 if (!marginal_memb)
5130 marginal_memb = memb;
5131 }
5132 }
5133
5134 /* Can convert integer zero to any pointer type. */
5135 if (null_pointer_constant)
5136 {
5137 rhs = null_pointer_node;
5138 break;
5139 }
5140 }
5141
5142 if (memb || marginal_memb)
5143 {
5144 if (!memb)
5145 {
5146 /* We have only a marginally acceptable member type;
5147 it needs a warning. */
5148 tree ttl = TREE_TYPE (TREE_TYPE (marginal_memb));
5149 tree ttr = TREE_TYPE (rhstype);
5150
5151 /* Const and volatile mean something different for function
5152 types, so the usual warnings are not appropriate. */
5153 if (TREE_CODE (ttr) == FUNCTION_TYPE
5154 && TREE_CODE (ttl) == FUNCTION_TYPE)
5155 {
5156 /* Because const and volatile on functions are
5157 restrictions that say the function will not do
5158 certain things, it is okay to use a const or volatile
5159 function where an ordinary one is wanted, but not
5160 vice-versa. */
5161 if (TYPE_QUALS_NO_ADDR_SPACE (ttl)
5162 & ~TYPE_QUALS_NO_ADDR_SPACE (ttr))
5163 WARN_FOR_ASSIGNMENT (location, 0,
5164 G_("passing argument %d of %qE "
5165 "makes qualified function "
5166 "pointer from unqualified"),
5167 G_("assignment makes qualified "
5168 "function pointer from "
5169 "unqualified"),
5170 G_("initialization makes qualified "
5171 "function pointer from "
5172 "unqualified"),
5173 G_("return makes qualified function "
5174 "pointer from unqualified"));
5175 }
5176 else if (TYPE_QUALS_NO_ADDR_SPACE (ttr)
5177 & ~TYPE_QUALS_NO_ADDR_SPACE (ttl))
5178 WARN_FOR_ASSIGNMENT (location, 0,
5179 G_("passing argument %d of %qE discards "
5180 "qualifiers from pointer target type"),
5181 G_("assignment discards qualifiers "
5182 "from pointer target type"),
5183 G_("initialization discards qualifiers "
5184 "from pointer target type"),
5185 G_("return discards qualifiers from "
5186 "pointer target type"));
5187
5188 memb = marginal_memb;
5189 }
5190
5191 if (!fundecl || !DECL_IN_SYSTEM_HEADER (fundecl))
5192 pedwarn (location, OPT_pedantic,
5193 "ISO C prohibits argument conversion to union type");
5194
5195 rhs = fold_convert_loc (location, TREE_TYPE (memb), rhs);
5196 return build_constructor_single (type, memb, rhs);
5197 }
5198 }
5199
5200 /* Conversions among pointers */
5201 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
5202 && (coder == codel))
5203 {
5204 tree ttl = TREE_TYPE (type);
5205 tree ttr = TREE_TYPE (rhstype);
5206 tree mvl = ttl;
5207 tree mvr = ttr;
5208 bool is_opaque_pointer;
5209 int target_cmp = 0; /* Cache comp_target_types () result. */
5210 addr_space_t asl;
5211 addr_space_t asr;
5212
5213 if (TREE_CODE (mvl) != ARRAY_TYPE)
5214 mvl = TYPE_MAIN_VARIANT (mvl);
5215 if (TREE_CODE (mvr) != ARRAY_TYPE)
5216 mvr = TYPE_MAIN_VARIANT (mvr);
5217 /* Opaque pointers are treated like void pointers. */
5218 is_opaque_pointer = vector_targets_convertible_p (ttl, ttr);
5219
5220 /* C++ does not allow the implicit conversion void* -> T*. However,
5221 for the purpose of reducing the number of false positives, we
5222 tolerate the special case of
5223
5224 int *p = NULL;
5225
5226 where NULL is typically defined in C to be '(void *) 0'. */
5227 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl))
5228 warning_at (location, OPT_Wc___compat,
5229 "request for implicit conversion "
5230 "from %qT to %qT not permitted in C++", rhstype, type);
5231
5232 /* See if the pointers point to incompatible address spaces. */
5233 asl = TYPE_ADDR_SPACE (ttl);
5234 asr = TYPE_ADDR_SPACE (ttr);
5235 if (!null_pointer_constant_p (rhs)
5236 && asr != asl && !targetm.addr_space.subset_p (asr, asl))
5237 {
5238 switch (errtype)
5239 {
5240 case ic_argpass:
5241 error_at (location, "passing argument %d of %qE from pointer to "
5242 "non-enclosed address space", parmnum, rname);
5243 break;
5244 case ic_assign:
5245 error_at (location, "assignment from pointer to "
5246 "non-enclosed address space");
5247 break;
5248 case ic_init:
5249 error_at (location, "initialization from pointer to "
5250 "non-enclosed address space");
5251 break;
5252 case ic_return:
5253 error_at (location, "return from pointer to "
5254 "non-enclosed address space");
5255 break;
5256 default:
5257 gcc_unreachable ();
5258 }
5259 return error_mark_node;
5260 }
5261
5262 /* Check if the right-hand side has a format attribute but the
5263 left-hand side doesn't. */
5264 if (warn_missing_format_attribute
5265 && check_missing_format_attribute (type, rhstype))
5266 {
5267 switch (errtype)
5268 {
5269 case ic_argpass:
5270 warning_at (location, OPT_Wmissing_format_attribute,
5271 "argument %d of %qE might be "
5272 "a candidate for a format attribute",
5273 parmnum, rname);
5274 break;
5275 case ic_assign:
5276 warning_at (location, OPT_Wmissing_format_attribute,
5277 "assignment left-hand side might be "
5278 "a candidate for a format attribute");
5279 break;
5280 case ic_init:
5281 warning_at (location, OPT_Wmissing_format_attribute,
5282 "initialization left-hand side might be "
5283 "a candidate for a format attribute");
5284 break;
5285 case ic_return:
5286 warning_at (location, OPT_Wmissing_format_attribute,
5287 "return type might be "
5288 "a candidate for a format attribute");
5289 break;
5290 default:
5291 gcc_unreachable ();
5292 }
5293 }
5294
5295 /* Any non-function converts to a [const][volatile] void *
5296 and vice versa; otherwise, targets must be the same.
5297 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
5298 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
5299 || (target_cmp = comp_target_types (location, type, rhstype))
5300 || is_opaque_pointer
5301 || (c_common_unsigned_type (mvl)
5302 == c_common_unsigned_type (mvr)))
5303 {
5304 if (pedantic
5305 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
5306 ||
5307 (VOID_TYPE_P (ttr)
5308 && !null_pointer_constant
5309 && TREE_CODE (ttl) == FUNCTION_TYPE)))
5310 WARN_FOR_ASSIGNMENT (location, OPT_pedantic,
5311 G_("ISO C forbids passing argument %d of "
5312 "%qE between function pointer "
5313 "and %<void *%>"),
5314 G_("ISO C forbids assignment between "
5315 "function pointer and %<void *%>"),
5316 G_("ISO C forbids initialization between "
5317 "function pointer and %<void *%>"),
5318 G_("ISO C forbids return between function "
5319 "pointer and %<void *%>"));
5320 /* Const and volatile mean something different for function types,
5321 so the usual warnings are not appropriate. */
5322 else if (TREE_CODE (ttr) != FUNCTION_TYPE
5323 && TREE_CODE (ttl) != FUNCTION_TYPE)
5324 {
5325 if (TYPE_QUALS_NO_ADDR_SPACE (ttr)
5326 & ~TYPE_QUALS_NO_ADDR_SPACE (ttl))
5327 {
5328 /* Types differing only by the presence of the 'volatile'
5329 qualifier are acceptable if the 'volatile' has been added
5330 in by the Objective-C EH machinery. */
5331 if (!objc_type_quals_match (ttl, ttr))
5332 WARN_FOR_ASSIGNMENT (location, 0,
5333 G_("passing argument %d of %qE discards "
5334 "qualifiers from pointer target type"),
5335 G_("assignment discards qualifiers "
5336 "from pointer target type"),
5337 G_("initialization discards qualifiers "
5338 "from pointer target type"),
5339 G_("return discards qualifiers from "
5340 "pointer target type"));
5341 }
5342 /* If this is not a case of ignoring a mismatch in signedness,
5343 no warning. */
5344 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
5345 || target_cmp)
5346 ;
5347 /* If there is a mismatch, do warn. */
5348 else if (warn_pointer_sign)
5349 WARN_FOR_ASSIGNMENT (location, OPT_Wpointer_sign,
5350 G_("pointer targets in passing argument "
5351 "%d of %qE differ in signedness"),
5352 G_("pointer targets in assignment "
5353 "differ in signedness"),
5354 G_("pointer targets in initialization "
5355 "differ in signedness"),
5356 G_("pointer targets in return differ "
5357 "in signedness"));
5358 }
5359 else if (TREE_CODE (ttl) == FUNCTION_TYPE
5360 && TREE_CODE (ttr) == FUNCTION_TYPE)
5361 {
5362 /* Because const and volatile on functions are restrictions
5363 that say the function will not do certain things,
5364 it is okay to use a const or volatile function
5365 where an ordinary one is wanted, but not vice-versa. */
5366 if (TYPE_QUALS_NO_ADDR_SPACE (ttl)
5367 & ~TYPE_QUALS_NO_ADDR_SPACE (ttr))
5368 WARN_FOR_ASSIGNMENT (location, 0,
5369 G_("passing argument %d of %qE makes "
5370 "qualified function pointer "
5371 "from unqualified"),
5372 G_("assignment makes qualified function "
5373 "pointer from unqualified"),
5374 G_("initialization makes qualified "
5375 "function pointer from unqualified"),
5376 G_("return makes qualified function "
5377 "pointer from unqualified"));
5378 }
5379 }
5380 else
5381 /* Avoid warning about the volatile ObjC EH puts on decls. */
5382 if (!objc_ok)
5383 WARN_FOR_ASSIGNMENT (location, 0,
5384 G_("passing argument %d of %qE from "
5385 "incompatible pointer type"),
5386 G_("assignment from incompatible pointer type"),
5387 G_("initialization from incompatible "
5388 "pointer type"),
5389 G_("return from incompatible pointer type"));
5390
5391 return convert (type, rhs);
5392 }
5393 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
5394 {
5395 /* ??? This should not be an error when inlining calls to
5396 unprototyped functions. */
5397 error_at (location, "invalid use of non-lvalue array");
5398 return error_mark_node;
5399 }
5400 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
5401 {
5402 /* An explicit constant 0 can convert to a pointer,
5403 or one that results from arithmetic, even including
5404 a cast to integer type. */
5405 if (!null_pointer_constant)
5406 WARN_FOR_ASSIGNMENT (location, 0,
5407 G_("passing argument %d of %qE makes "
5408 "pointer from integer without a cast"),
5409 G_("assignment makes pointer from integer "
5410 "without a cast"),
5411 G_("initialization makes pointer from "
5412 "integer without a cast"),
5413 G_("return makes pointer from integer "
5414 "without a cast"));
5415
5416 return convert (type, rhs);
5417 }
5418 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
5419 {
5420 WARN_FOR_ASSIGNMENT (location, 0,
5421 G_("passing argument %d of %qE makes integer "
5422 "from pointer without a cast"),
5423 G_("assignment makes integer from pointer "
5424 "without a cast"),
5425 G_("initialization makes integer from pointer "
5426 "without a cast"),
5427 G_("return makes integer from pointer "
5428 "without a cast"));
5429 return convert (type, rhs);
5430 }
5431 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
5432 {
5433 tree ret;
5434 bool save = in_late_binary_op;
5435 in_late_binary_op = true;
5436 ret = convert (type, rhs);
5437 in_late_binary_op = save;
5438 return ret;
5439 }
5440
5441 switch (errtype)
5442 {
5443 case ic_argpass:
5444 error_at (location, "incompatible type for argument %d of %qE", parmnum, rname);
5445 inform ((fundecl && !DECL_IS_BUILTIN (fundecl))
5446 ? DECL_SOURCE_LOCATION (fundecl) : input_location,
5447 "expected %qT but argument is of type %qT", type, rhstype);
5448 break;
5449 case ic_assign:
5450 error_at (location, "incompatible types when assigning to type %qT from "
5451 "type %qT", type, rhstype);
5452 break;
5453 case ic_init:
5454 error_at (location,
5455 "incompatible types when initializing type %qT using type %qT",
5456 type, rhstype);
5457 break;
5458 case ic_return:
5459 error_at (location,
5460 "incompatible types when returning type %qT but %qT was "
5461 "expected", rhstype, type);
5462 break;
5463 default:
5464 gcc_unreachable ();
5465 }
5466
5467 return error_mark_node;
5468 }
5469 \f
5470 /* If VALUE is a compound expr all of whose expressions are constant, then
5471 return its value. Otherwise, return error_mark_node.
5472
5473 This is for handling COMPOUND_EXPRs as initializer elements
5474 which is allowed with a warning when -pedantic is specified. */
5475
5476 static tree
5477 valid_compound_expr_initializer (tree value, tree endtype)
5478 {
5479 if (TREE_CODE (value) == COMPOUND_EXPR)
5480 {
5481 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
5482 == error_mark_node)
5483 return error_mark_node;
5484 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
5485 endtype);
5486 }
5487 else if (!initializer_constant_valid_p (value, endtype))
5488 return error_mark_node;
5489 else
5490 return value;
5491 }
5492 \f
5493 /* Perform appropriate conversions on the initial value of a variable,
5494 store it in the declaration DECL,
5495 and print any error messages that are appropriate.
5496 If ORIGTYPE is not NULL_TREE, it is the original type of INIT.
5497 If the init is invalid, store an ERROR_MARK.
5498
5499 INIT_LOC is the location of the initial value. */
5500
5501 void
5502 store_init_value (location_t init_loc, tree decl, tree init, tree origtype)
5503 {
5504 tree value, type;
5505 bool npc = false;
5506
5507 /* If variable's type was invalidly declared, just ignore it. */
5508
5509 type = TREE_TYPE (decl);
5510 if (TREE_CODE (type) == ERROR_MARK)
5511 return;
5512
5513 /* Digest the specified initializer into an expression. */
5514
5515 if (init)
5516 npc = null_pointer_constant_p (init);
5517 value = digest_init (init_loc, type, init, origtype, npc,
5518 true, TREE_STATIC (decl));
5519
5520 /* Store the expression if valid; else report error. */
5521
5522 if (!in_system_header
5523 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
5524 warning (OPT_Wtraditional, "traditional C rejects automatic "
5525 "aggregate initialization");
5526
5527 DECL_INITIAL (decl) = value;
5528
5529 /* ANSI wants warnings about out-of-range constant initializers. */
5530 STRIP_TYPE_NOPS (value);
5531 if (TREE_STATIC (decl))
5532 constant_expression_warning (value);
5533
5534 /* Check if we need to set array size from compound literal size. */
5535 if (TREE_CODE (type) == ARRAY_TYPE
5536 && TYPE_DOMAIN (type) == 0
5537 && value != error_mark_node)
5538 {
5539 tree inside_init = init;
5540
5541 STRIP_TYPE_NOPS (inside_init);
5542 inside_init = fold (inside_init);
5543
5544 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
5545 {
5546 tree cldecl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
5547
5548 if (TYPE_DOMAIN (TREE_TYPE (cldecl)))
5549 {
5550 /* For int foo[] = (int [3]){1}; we need to set array size
5551 now since later on array initializer will be just the
5552 brace enclosed list of the compound literal. */
5553 type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
5554 TREE_TYPE (decl) = type;
5555 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (cldecl));
5556 layout_type (type);
5557 layout_decl (cldecl, 0);
5558 }
5559 }
5560 }
5561 }
5562 \f
5563 /* Methods for storing and printing names for error messages. */
5564
5565 /* Implement a spelling stack that allows components of a name to be pushed
5566 and popped. Each element on the stack is this structure. */
5567
5568 struct spelling
5569 {
5570 int kind;
5571 union
5572 {
5573 unsigned HOST_WIDE_INT i;
5574 const char *s;
5575 } u;
5576 };
5577
5578 #define SPELLING_STRING 1
5579 #define SPELLING_MEMBER 2
5580 #define SPELLING_BOUNDS 3
5581
5582 static struct spelling *spelling; /* Next stack element (unused). */
5583 static struct spelling *spelling_base; /* Spelling stack base. */
5584 static int spelling_size; /* Size of the spelling stack. */
5585
5586 /* Macros to save and restore the spelling stack around push_... functions.
5587 Alternative to SAVE_SPELLING_STACK. */
5588
5589 #define SPELLING_DEPTH() (spelling - spelling_base)
5590 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
5591
5592 /* Push an element on the spelling stack with type KIND and assign VALUE
5593 to MEMBER. */
5594
5595 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
5596 { \
5597 int depth = SPELLING_DEPTH (); \
5598 \
5599 if (depth >= spelling_size) \
5600 { \
5601 spelling_size += 10; \
5602 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
5603 spelling_size); \
5604 RESTORE_SPELLING_DEPTH (depth); \
5605 } \
5606 \
5607 spelling->kind = (KIND); \
5608 spelling->MEMBER = (VALUE); \
5609 spelling++; \
5610 }
5611
5612 /* Push STRING on the stack. Printed literally. */
5613
5614 static void
5615 push_string (const char *string)
5616 {
5617 PUSH_SPELLING (SPELLING_STRING, string, u.s);
5618 }
5619
5620 /* Push a member name on the stack. Printed as '.' STRING. */
5621
5622 static void
5623 push_member_name (tree decl)
5624 {
5625 const char *const string
5626 = (DECL_NAME (decl)
5627 ? identifier_to_locale (IDENTIFIER_POINTER (DECL_NAME (decl)))
5628 : _("<anonymous>"));
5629 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
5630 }
5631
5632 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
5633
5634 static void
5635 push_array_bounds (unsigned HOST_WIDE_INT bounds)
5636 {
5637 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
5638 }
5639
5640 /* Compute the maximum size in bytes of the printed spelling. */
5641
5642 static int
5643 spelling_length (void)
5644 {
5645 int size = 0;
5646 struct spelling *p;
5647
5648 for (p = spelling_base; p < spelling; p++)
5649 {
5650 if (p->kind == SPELLING_BOUNDS)
5651 size += 25;
5652 else
5653 size += strlen (p->u.s) + 1;
5654 }
5655
5656 return size;
5657 }
5658
5659 /* Print the spelling to BUFFER and return it. */
5660
5661 static char *
5662 print_spelling (char *buffer)
5663 {
5664 char *d = buffer;
5665 struct spelling *p;
5666
5667 for (p = spelling_base; p < spelling; p++)
5668 if (p->kind == SPELLING_BOUNDS)
5669 {
5670 sprintf (d, "[" HOST_WIDE_INT_PRINT_UNSIGNED "]", p->u.i);
5671 d += strlen (d);
5672 }
5673 else
5674 {
5675 const char *s;
5676 if (p->kind == SPELLING_MEMBER)
5677 *d++ = '.';
5678 for (s = p->u.s; (*d = *s++); d++)
5679 ;
5680 }
5681 *d++ = '\0';
5682 return buffer;
5683 }
5684
5685 /* Issue an error message for a bad initializer component.
5686 MSGID identifies the message.
5687 The component name is taken from the spelling stack. */
5688
5689 void
5690 error_init (const char *msgid)
5691 {
5692 char *ofwhat;
5693
5694 error ("%s", _(msgid));
5695 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
5696 if (*ofwhat)
5697 error ("(near initialization for %qs)", ofwhat);
5698 }
5699
5700 /* Issue a pedantic warning for a bad initializer component. OPT is
5701 the option OPT_* (from options.h) controlling this warning or 0 if
5702 it is unconditionally given. MSGID identifies the message. The
5703 component name is taken from the spelling stack. */
5704
5705 void
5706 pedwarn_init (location_t location, int opt, const char *msgid)
5707 {
5708 char *ofwhat;
5709
5710 pedwarn (location, opt, "%s", _(msgid));
5711 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
5712 if (*ofwhat)
5713 pedwarn (location, opt, "(near initialization for %qs)", ofwhat);
5714 }
5715
5716 /* Issue a warning for a bad initializer component.
5717
5718 OPT is the OPT_W* value corresponding to the warning option that
5719 controls this warning. MSGID identifies the message. The
5720 component name is taken from the spelling stack. */
5721
5722 static void
5723 warning_init (int opt, const char *msgid)
5724 {
5725 char *ofwhat;
5726
5727 warning (opt, "%s", _(msgid));
5728 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
5729 if (*ofwhat)
5730 warning (opt, "(near initialization for %qs)", ofwhat);
5731 }
5732 \f
5733 /* If TYPE is an array type and EXPR is a parenthesized string
5734 constant, warn if pedantic that EXPR is being used to initialize an
5735 object of type TYPE. */
5736
5737 void
5738 maybe_warn_string_init (tree type, struct c_expr expr)
5739 {
5740 if (pedantic
5741 && TREE_CODE (type) == ARRAY_TYPE
5742 && TREE_CODE (expr.value) == STRING_CST
5743 && expr.original_code != STRING_CST)
5744 pedwarn_init (input_location, OPT_pedantic,
5745 "array initialized from parenthesized string constant");
5746 }
5747
5748 /* Digest the parser output INIT as an initializer for type TYPE.
5749 Return a C expression of type TYPE to represent the initial value.
5750
5751 If ORIGTYPE is not NULL_TREE, it is the original type of INIT.
5752
5753 NULL_POINTER_CONSTANT is true if INIT is a null pointer constant.
5754
5755 If INIT is a string constant, STRICT_STRING is true if it is
5756 unparenthesized or we should not warn here for it being parenthesized.
5757 For other types of INIT, STRICT_STRING is not used.
5758
5759 INIT_LOC is the location of the INIT.
5760
5761 REQUIRE_CONSTANT requests an error if non-constant initializers or
5762 elements are seen. */
5763
5764 static tree
5765 digest_init (location_t init_loc, tree type, tree init, tree origtype,
5766 bool null_pointer_constant, bool strict_string,
5767 int require_constant)
5768 {
5769 enum tree_code code = TREE_CODE (type);
5770 tree inside_init = init;
5771 tree semantic_type = NULL_TREE;
5772 bool maybe_const = true;
5773
5774 if (type == error_mark_node
5775 || !init
5776 || init == error_mark_node
5777 || TREE_TYPE (init) == error_mark_node)
5778 return error_mark_node;
5779
5780 STRIP_TYPE_NOPS (inside_init);
5781
5782 if (TREE_CODE (inside_init) == EXCESS_PRECISION_EXPR)
5783 {
5784 semantic_type = TREE_TYPE (inside_init);
5785 inside_init = TREE_OPERAND (inside_init, 0);
5786 }
5787 inside_init = c_fully_fold (inside_init, require_constant, &maybe_const);
5788 inside_init = decl_constant_value_for_optimization (inside_init);
5789
5790 /* Initialization of an array of chars from a string constant
5791 optionally enclosed in braces. */
5792
5793 if (code == ARRAY_TYPE && inside_init
5794 && TREE_CODE (inside_init) == STRING_CST)
5795 {
5796 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
5797 /* Note that an array could be both an array of character type
5798 and an array of wchar_t if wchar_t is signed char or unsigned
5799 char. */
5800 bool char_array = (typ1 == char_type_node
5801 || typ1 == signed_char_type_node
5802 || typ1 == unsigned_char_type_node);
5803 bool wchar_array = !!comptypes (typ1, wchar_type_node);
5804 bool char16_array = !!comptypes (typ1, char16_type_node);
5805 bool char32_array = !!comptypes (typ1, char32_type_node);
5806
5807 if (char_array || wchar_array || char16_array || char32_array)
5808 {
5809 struct c_expr expr;
5810 tree typ2 = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)));
5811 expr.value = inside_init;
5812 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
5813 expr.original_type = NULL;
5814 maybe_warn_string_init (type, expr);
5815
5816 if (TYPE_DOMAIN (type) && !TYPE_MAX_VALUE (TYPE_DOMAIN (type)))
5817 pedwarn_init (init_loc, OPT_pedantic,
5818 "initialization of a flexible array member");
5819
5820 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
5821 TYPE_MAIN_VARIANT (type)))
5822 return inside_init;
5823
5824 if (char_array)
5825 {
5826 if (typ2 != char_type_node)
5827 {
5828 error_init ("char-array initialized from wide string");
5829 return error_mark_node;
5830 }
5831 }
5832 else
5833 {
5834 if (typ2 == char_type_node)
5835 {
5836 error_init ("wide character array initialized from non-wide "
5837 "string");
5838 return error_mark_node;
5839 }
5840 else if (!comptypes(typ1, typ2))
5841 {
5842 error_init ("wide character array initialized from "
5843 "incompatible wide string");
5844 return error_mark_node;
5845 }
5846 }
5847
5848 TREE_TYPE (inside_init) = type;
5849 if (TYPE_DOMAIN (type) != 0
5850 && TYPE_SIZE (type) != 0
5851 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST)
5852 {
5853 unsigned HOST_WIDE_INT len = TREE_STRING_LENGTH (inside_init);
5854
5855 /* Subtract the size of a single (possibly wide) character
5856 because it's ok to ignore the terminating null char
5857 that is counted in the length of the constant. */
5858 if (0 > compare_tree_int (TYPE_SIZE_UNIT (type),
5859 (len
5860 - (TYPE_PRECISION (typ1)
5861 / BITS_PER_UNIT))))
5862 pedwarn_init (init_loc, 0,
5863 ("initializer-string for array of chars "
5864 "is too long"));
5865 else if (warn_cxx_compat
5866 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type), len))
5867 warning_at (init_loc, OPT_Wc___compat,
5868 ("initializer-string for array chars "
5869 "is too long for C++"));
5870 }
5871
5872 return inside_init;
5873 }
5874 else if (INTEGRAL_TYPE_P (typ1))
5875 {
5876 error_init ("array of inappropriate type initialized "
5877 "from string constant");
5878 return error_mark_node;
5879 }
5880 }
5881
5882 /* Build a VECTOR_CST from a *constant* vector constructor. If the
5883 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
5884 below and handle as a constructor. */
5885 if (code == VECTOR_TYPE
5886 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
5887 && vector_types_convertible_p (TREE_TYPE (inside_init), type, true)
5888 && TREE_CONSTANT (inside_init))
5889 {
5890 if (TREE_CODE (inside_init) == VECTOR_CST
5891 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
5892 TYPE_MAIN_VARIANT (type)))
5893 return inside_init;
5894
5895 if (TREE_CODE (inside_init) == CONSTRUCTOR)
5896 {
5897 unsigned HOST_WIDE_INT ix;
5898 tree value;
5899 bool constant_p = true;
5900
5901 /* Iterate through elements and check if all constructor
5902 elements are *_CSTs. */
5903 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (inside_init), ix, value)
5904 if (!CONSTANT_CLASS_P (value))
5905 {
5906 constant_p = false;
5907 break;
5908 }
5909
5910 if (constant_p)
5911 return build_vector_from_ctor (type,
5912 CONSTRUCTOR_ELTS (inside_init));
5913 }
5914 }
5915
5916 if (warn_sequence_point)
5917 verify_sequence_points (inside_init);
5918
5919 /* Any type can be initialized
5920 from an expression of the same type, optionally with braces. */
5921
5922 if (inside_init && TREE_TYPE (inside_init) != 0
5923 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
5924 TYPE_MAIN_VARIANT (type))
5925 || (code == ARRAY_TYPE
5926 && comptypes (TREE_TYPE (inside_init), type))
5927 || (code == VECTOR_TYPE
5928 && comptypes (TREE_TYPE (inside_init), type))
5929 || (code == POINTER_TYPE
5930 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
5931 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
5932 TREE_TYPE (type)))))
5933 {
5934 if (code == POINTER_TYPE)
5935 {
5936 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
5937 {
5938 if (TREE_CODE (inside_init) == STRING_CST
5939 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
5940 inside_init = array_to_pointer_conversion
5941 (init_loc, inside_init);
5942 else
5943 {
5944 error_init ("invalid use of non-lvalue array");
5945 return error_mark_node;
5946 }
5947 }
5948 }
5949
5950 if (code == VECTOR_TYPE)
5951 /* Although the types are compatible, we may require a
5952 conversion. */
5953 inside_init = convert (type, inside_init);
5954
5955 if (require_constant
5956 && (code == VECTOR_TYPE || !flag_isoc99)
5957 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
5958 {
5959 /* As an extension, allow initializing objects with static storage
5960 duration with compound literals (which are then treated just as
5961 the brace enclosed list they contain). Also allow this for
5962 vectors, as we can only assign them with compound literals. */
5963 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
5964 inside_init = DECL_INITIAL (decl);
5965 }
5966
5967 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
5968 && TREE_CODE (inside_init) != CONSTRUCTOR)
5969 {
5970 error_init ("array initialized from non-constant array expression");
5971 return error_mark_node;
5972 }
5973
5974 /* Compound expressions can only occur here if -pedantic or
5975 -pedantic-errors is specified. In the later case, we always want
5976 an error. In the former case, we simply want a warning. */
5977 if (require_constant && pedantic
5978 && TREE_CODE (inside_init) == COMPOUND_EXPR)
5979 {
5980 inside_init
5981 = valid_compound_expr_initializer (inside_init,
5982 TREE_TYPE (inside_init));
5983 if (inside_init == error_mark_node)
5984 error_init ("initializer element is not constant");
5985 else
5986 pedwarn_init (init_loc, OPT_pedantic,
5987 "initializer element is not constant");
5988 if (flag_pedantic_errors)
5989 inside_init = error_mark_node;
5990 }
5991 else if (require_constant
5992 && !initializer_constant_valid_p (inside_init,
5993 TREE_TYPE (inside_init)))
5994 {
5995 error_init ("initializer element is not constant");
5996 inside_init = error_mark_node;
5997 }
5998 else if (require_constant && !maybe_const)
5999 pedwarn_init (init_loc, 0,
6000 "initializer element is not a constant expression");
6001
6002 /* Added to enable additional -Wmissing-format-attribute warnings. */
6003 if (TREE_CODE (TREE_TYPE (inside_init)) == POINTER_TYPE)
6004 inside_init = convert_for_assignment (init_loc, type, inside_init,
6005 origtype,
6006 ic_init, null_pointer_constant,
6007 NULL_TREE, NULL_TREE, 0);
6008 return inside_init;
6009 }
6010
6011 /* Handle scalar types, including conversions. */
6012
6013 if (code == INTEGER_TYPE || code == REAL_TYPE || code == FIXED_POINT_TYPE
6014 || code == POINTER_TYPE || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE
6015 || code == COMPLEX_TYPE || code == VECTOR_TYPE)
6016 {
6017 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE
6018 && (TREE_CODE (init) == STRING_CST
6019 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR))
6020 inside_init = init = array_to_pointer_conversion (init_loc, init);
6021 if (semantic_type)
6022 inside_init = build1 (EXCESS_PRECISION_EXPR, semantic_type,
6023 inside_init);
6024 inside_init
6025 = convert_for_assignment (init_loc, type, inside_init, origtype,
6026 ic_init, null_pointer_constant,
6027 NULL_TREE, NULL_TREE, 0);
6028
6029 /* Check to see if we have already given an error message. */
6030 if (inside_init == error_mark_node)
6031 ;
6032 else if (require_constant && !TREE_CONSTANT (inside_init))
6033 {
6034 error_init ("initializer element is not constant");
6035 inside_init = error_mark_node;
6036 }
6037 else if (require_constant
6038 && !initializer_constant_valid_p (inside_init,
6039 TREE_TYPE (inside_init)))
6040 {
6041 error_init ("initializer element is not computable at load time");
6042 inside_init = error_mark_node;
6043 }
6044 else if (require_constant && !maybe_const)
6045 pedwarn_init (init_loc, 0,
6046 "initializer element is not a constant expression");
6047
6048 return inside_init;
6049 }
6050
6051 /* Come here only for records and arrays. */
6052
6053 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
6054 {
6055 error_init ("variable-sized object may not be initialized");
6056 return error_mark_node;
6057 }
6058
6059 error_init ("invalid initializer");
6060 return error_mark_node;
6061 }
6062 \f
6063 /* Handle initializers that use braces. */
6064
6065 /* Type of object we are accumulating a constructor for.
6066 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
6067 static tree constructor_type;
6068
6069 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
6070 left to fill. */
6071 static tree constructor_fields;
6072
6073 /* For an ARRAY_TYPE, this is the specified index
6074 at which to store the next element we get. */
6075 static tree constructor_index;
6076
6077 /* For an ARRAY_TYPE, this is the maximum index. */
6078 static tree constructor_max_index;
6079
6080 /* For a RECORD_TYPE, this is the first field not yet written out. */
6081 static tree constructor_unfilled_fields;
6082
6083 /* For an ARRAY_TYPE, this is the index of the first element
6084 not yet written out. */
6085 static tree constructor_unfilled_index;
6086
6087 /* In a RECORD_TYPE, the byte index of the next consecutive field.
6088 This is so we can generate gaps between fields, when appropriate. */
6089 static tree constructor_bit_index;
6090
6091 /* If we are saving up the elements rather than allocating them,
6092 this is the list of elements so far (in reverse order,
6093 most recent first). */
6094 static VEC(constructor_elt,gc) *constructor_elements;
6095
6096 /* 1 if constructor should be incrementally stored into a constructor chain,
6097 0 if all the elements should be kept in AVL tree. */
6098 static int constructor_incremental;
6099
6100 /* 1 if so far this constructor's elements are all compile-time constants. */
6101 static int constructor_constant;
6102
6103 /* 1 if so far this constructor's elements are all valid address constants. */
6104 static int constructor_simple;
6105
6106 /* 1 if this constructor has an element that cannot be part of a
6107 constant expression. */
6108 static int constructor_nonconst;
6109
6110 /* 1 if this constructor is erroneous so far. */
6111 static int constructor_erroneous;
6112
6113 /* Structure for managing pending initializer elements, organized as an
6114 AVL tree. */
6115
6116 struct init_node
6117 {
6118 struct init_node *left, *right;
6119 struct init_node *parent;
6120 int balance;
6121 tree purpose;
6122 tree value;
6123 tree origtype;
6124 };
6125
6126 /* Tree of pending elements at this constructor level.
6127 These are elements encountered out of order
6128 which belong at places we haven't reached yet in actually
6129 writing the output.
6130 Will never hold tree nodes across GC runs. */
6131 static struct init_node *constructor_pending_elts;
6132
6133 /* The SPELLING_DEPTH of this constructor. */
6134 static int constructor_depth;
6135
6136 /* DECL node for which an initializer is being read.
6137 0 means we are reading a constructor expression
6138 such as (struct foo) {...}. */
6139 static tree constructor_decl;
6140
6141 /* Nonzero if this is an initializer for a top-level decl. */
6142 static int constructor_top_level;
6143
6144 /* Nonzero if there were any member designators in this initializer. */
6145 static int constructor_designated;
6146
6147 /* Nesting depth of designator list. */
6148 static int designator_depth;
6149
6150 /* Nonzero if there were diagnosed errors in this designator list. */
6151 static int designator_erroneous;
6152
6153 \f
6154 /* This stack has a level for each implicit or explicit level of
6155 structuring in the initializer, including the outermost one. It
6156 saves the values of most of the variables above. */
6157
6158 struct constructor_range_stack;
6159
6160 struct constructor_stack
6161 {
6162 struct constructor_stack *next;
6163 tree type;
6164 tree fields;
6165 tree index;
6166 tree max_index;
6167 tree unfilled_index;
6168 tree unfilled_fields;
6169 tree bit_index;
6170 VEC(constructor_elt,gc) *elements;
6171 struct init_node *pending_elts;
6172 int offset;
6173 int depth;
6174 /* If value nonzero, this value should replace the entire
6175 constructor at this level. */
6176 struct c_expr replacement_value;
6177 struct constructor_range_stack *range_stack;
6178 char constant;
6179 char simple;
6180 char nonconst;
6181 char implicit;
6182 char erroneous;
6183 char outer;
6184 char incremental;
6185 char designated;
6186 };
6187
6188 static struct constructor_stack *constructor_stack;
6189
6190 /* This stack represents designators from some range designator up to
6191 the last designator in the list. */
6192
6193 struct constructor_range_stack
6194 {
6195 struct constructor_range_stack *next, *prev;
6196 struct constructor_stack *stack;
6197 tree range_start;
6198 tree index;
6199 tree range_end;
6200 tree fields;
6201 };
6202
6203 static struct constructor_range_stack *constructor_range_stack;
6204
6205 /* This stack records separate initializers that are nested.
6206 Nested initializers can't happen in ANSI C, but GNU C allows them
6207 in cases like { ... (struct foo) { ... } ... }. */
6208
6209 struct initializer_stack
6210 {
6211 struct initializer_stack *next;
6212 tree decl;
6213 struct constructor_stack *constructor_stack;
6214 struct constructor_range_stack *constructor_range_stack;
6215 VEC(constructor_elt,gc) *elements;
6216 struct spelling *spelling;
6217 struct spelling *spelling_base;
6218 int spelling_size;
6219 char top_level;
6220 char require_constant_value;
6221 char require_constant_elements;
6222 };
6223
6224 static struct initializer_stack *initializer_stack;
6225 \f
6226 /* Prepare to parse and output the initializer for variable DECL. */
6227
6228 void
6229 start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
6230 {
6231 const char *locus;
6232 struct initializer_stack *p = XNEW (struct initializer_stack);
6233
6234 p->decl = constructor_decl;
6235 p->require_constant_value = require_constant_value;
6236 p->require_constant_elements = require_constant_elements;
6237 p->constructor_stack = constructor_stack;
6238 p->constructor_range_stack = constructor_range_stack;
6239 p->elements = constructor_elements;
6240 p->spelling = spelling;
6241 p->spelling_base = spelling_base;
6242 p->spelling_size = spelling_size;
6243 p->top_level = constructor_top_level;
6244 p->next = initializer_stack;
6245 initializer_stack = p;
6246
6247 constructor_decl = decl;
6248 constructor_designated = 0;
6249 constructor_top_level = top_level;
6250
6251 if (decl != 0 && decl != error_mark_node)
6252 {
6253 require_constant_value = TREE_STATIC (decl);
6254 require_constant_elements
6255 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
6256 /* For a scalar, you can always use any value to initialize,
6257 even within braces. */
6258 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
6259 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
6260 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
6261 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
6262 locus = identifier_to_locale (IDENTIFIER_POINTER (DECL_NAME (decl)));
6263 }
6264 else
6265 {
6266 require_constant_value = 0;
6267 require_constant_elements = 0;
6268 locus = _("(anonymous)");
6269 }
6270
6271 constructor_stack = 0;
6272 constructor_range_stack = 0;
6273
6274 missing_braces_mentioned = 0;
6275
6276 spelling_base = 0;
6277 spelling_size = 0;
6278 RESTORE_SPELLING_DEPTH (0);
6279
6280 if (locus)
6281 push_string (locus);
6282 }
6283
6284 void
6285 finish_init (void)
6286 {
6287 struct initializer_stack *p = initializer_stack;
6288
6289 /* Free the whole constructor stack of this initializer. */
6290 while (constructor_stack)
6291 {
6292 struct constructor_stack *q = constructor_stack;
6293 constructor_stack = q->next;
6294 free (q);
6295 }
6296
6297 gcc_assert (!constructor_range_stack);
6298
6299 /* Pop back to the data of the outer initializer (if any). */
6300 free (spelling_base);
6301
6302 constructor_decl = p->decl;
6303 require_constant_value = p->require_constant_value;
6304 require_constant_elements = p->require_constant_elements;
6305 constructor_stack = p->constructor_stack;
6306 constructor_range_stack = p->constructor_range_stack;
6307 constructor_elements = p->elements;
6308 spelling = p->spelling;
6309 spelling_base = p->spelling_base;
6310 spelling_size = p->spelling_size;
6311 constructor_top_level = p->top_level;
6312 initializer_stack = p->next;
6313 free (p);
6314 }
6315 \f
6316 /* Call here when we see the initializer is surrounded by braces.
6317 This is instead of a call to push_init_level;
6318 it is matched by a call to pop_init_level.
6319
6320 TYPE is the type to initialize, for a constructor expression.
6321 For an initializer for a decl, TYPE is zero. */
6322
6323 void
6324 really_start_incremental_init (tree type)
6325 {
6326 struct constructor_stack *p = XNEW (struct constructor_stack);
6327
6328 if (type == 0)
6329 type = TREE_TYPE (constructor_decl);
6330
6331 if (TREE_CODE (type) == VECTOR_TYPE
6332 && TYPE_VECTOR_OPAQUE (type))
6333 error ("opaque vector types cannot be initialized");
6334
6335 p->type = constructor_type;
6336 p->fields = constructor_fields;
6337 p->index = constructor_index;
6338 p->max_index = constructor_max_index;
6339 p->unfilled_index = constructor_unfilled_index;
6340 p->unfilled_fields = constructor_unfilled_fields;
6341 p->bit_index = constructor_bit_index;
6342 p->elements = constructor_elements;
6343 p->constant = constructor_constant;
6344 p->simple = constructor_simple;
6345 p->nonconst = constructor_nonconst;
6346 p->erroneous = constructor_erroneous;
6347 p->pending_elts = constructor_pending_elts;
6348 p->depth = constructor_depth;
6349 p->replacement_value.value = 0;
6350 p->replacement_value.original_code = ERROR_MARK;
6351 p->replacement_value.original_type = NULL;
6352 p->implicit = 0;
6353 p->range_stack = 0;
6354 p->outer = 0;
6355 p->incremental = constructor_incremental;
6356 p->designated = constructor_designated;
6357 p->next = 0;
6358 constructor_stack = p;
6359
6360 constructor_constant = 1;
6361 constructor_simple = 1;
6362 constructor_nonconst = 0;
6363 constructor_depth = SPELLING_DEPTH ();
6364 constructor_elements = 0;
6365 constructor_pending_elts = 0;
6366 constructor_type = type;
6367 constructor_incremental = 1;
6368 constructor_designated = 0;
6369 designator_depth = 0;
6370 designator_erroneous = 0;
6371
6372 if (TREE_CODE (constructor_type) == RECORD_TYPE
6373 || TREE_CODE (constructor_type) == UNION_TYPE)
6374 {
6375 constructor_fields = TYPE_FIELDS (constructor_type);
6376 /* Skip any nameless bit fields at the beginning. */
6377 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
6378 && DECL_NAME (constructor_fields) == 0)
6379 constructor_fields = TREE_CHAIN (constructor_fields);
6380
6381 constructor_unfilled_fields = constructor_fields;
6382 constructor_bit_index = bitsize_zero_node;
6383 }
6384 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6385 {
6386 if (TYPE_DOMAIN (constructor_type))
6387 {
6388 constructor_max_index
6389 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
6390
6391 /* Detect non-empty initializations of zero-length arrays. */
6392 if (constructor_max_index == NULL_TREE
6393 && TYPE_SIZE (constructor_type))
6394 constructor_max_index = build_int_cst (NULL_TREE, -1);
6395
6396 /* constructor_max_index needs to be an INTEGER_CST. Attempts
6397 to initialize VLAs will cause a proper error; avoid tree
6398 checking errors as well by setting a safe value. */
6399 if (constructor_max_index
6400 && TREE_CODE (constructor_max_index) != INTEGER_CST)
6401 constructor_max_index = build_int_cst (NULL_TREE, -1);
6402
6403 constructor_index
6404 = convert (bitsizetype,
6405 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
6406 }
6407 else
6408 {
6409 constructor_index = bitsize_zero_node;
6410 constructor_max_index = NULL_TREE;
6411 }
6412
6413 constructor_unfilled_index = constructor_index;
6414 }
6415 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6416 {
6417 /* Vectors are like simple fixed-size arrays. */
6418 constructor_max_index =
6419 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
6420 constructor_index = bitsize_zero_node;
6421 constructor_unfilled_index = constructor_index;
6422 }
6423 else
6424 {
6425 /* Handle the case of int x = {5}; */
6426 constructor_fields = constructor_type;
6427 constructor_unfilled_fields = constructor_type;
6428 }
6429 }
6430 \f
6431 /* Push down into a subobject, for initialization.
6432 If this is for an explicit set of braces, IMPLICIT is 0.
6433 If it is because the next element belongs at a lower level,
6434 IMPLICIT is 1 (or 2 if the push is because of designator list). */
6435
6436 void
6437 push_init_level (int implicit, struct obstack * braced_init_obstack)
6438 {
6439 struct constructor_stack *p;
6440 tree value = NULL_TREE;
6441
6442 /* If we've exhausted any levels that didn't have braces,
6443 pop them now. If implicit == 1, this will have been done in
6444 process_init_element; do not repeat it here because in the case
6445 of excess initializers for an empty aggregate this leads to an
6446 infinite cycle of popping a level and immediately recreating
6447 it. */
6448 if (implicit != 1)
6449 {
6450 while (constructor_stack->implicit)
6451 {
6452 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6453 || TREE_CODE (constructor_type) == UNION_TYPE)
6454 && constructor_fields == 0)
6455 process_init_element (pop_init_level (1, braced_init_obstack),
6456 true, braced_init_obstack);
6457 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6458 && constructor_max_index
6459 && tree_int_cst_lt (constructor_max_index,
6460 constructor_index))
6461 process_init_element (pop_init_level (1, braced_init_obstack),
6462 true, braced_init_obstack);
6463 else
6464 break;
6465 }
6466 }
6467
6468 /* Unless this is an explicit brace, we need to preserve previous
6469 content if any. */
6470 if (implicit)
6471 {
6472 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6473 || TREE_CODE (constructor_type) == UNION_TYPE)
6474 && constructor_fields)
6475 value = find_init_member (constructor_fields, braced_init_obstack);
6476 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6477 value = find_init_member (constructor_index, braced_init_obstack);
6478 }
6479
6480 p = XNEW (struct constructor_stack);
6481 p->type = constructor_type;
6482 p->fields = constructor_fields;
6483 p->index = constructor_index;
6484 p->max_index = constructor_max_index;
6485 p->unfilled_index = constructor_unfilled_index;
6486 p->unfilled_fields = constructor_unfilled_fields;
6487 p->bit_index = constructor_bit_index;
6488 p->elements = constructor_elements;
6489 p->constant = constructor_constant;
6490 p->simple = constructor_simple;
6491 p->nonconst = constructor_nonconst;
6492 p->erroneous = constructor_erroneous;
6493 p->pending_elts = constructor_pending_elts;
6494 p->depth = constructor_depth;
6495 p->replacement_value.value = 0;
6496 p->replacement_value.original_code = ERROR_MARK;
6497 p->replacement_value.original_type = NULL;
6498 p->implicit = implicit;
6499 p->outer = 0;
6500 p->incremental = constructor_incremental;
6501 p->designated = constructor_designated;
6502 p->next = constructor_stack;
6503 p->range_stack = 0;
6504 constructor_stack = p;
6505
6506 constructor_constant = 1;
6507 constructor_simple = 1;
6508 constructor_nonconst = 0;
6509 constructor_depth = SPELLING_DEPTH ();
6510 constructor_elements = 0;
6511 constructor_incremental = 1;
6512 constructor_designated = 0;
6513 constructor_pending_elts = 0;
6514 if (!implicit)
6515 {
6516 p->range_stack = constructor_range_stack;
6517 constructor_range_stack = 0;
6518 designator_depth = 0;
6519 designator_erroneous = 0;
6520 }
6521
6522 /* Don't die if an entire brace-pair level is superfluous
6523 in the containing level. */
6524 if (constructor_type == 0)
6525 ;
6526 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6527 || TREE_CODE (constructor_type) == UNION_TYPE)
6528 {
6529 /* Don't die if there are extra init elts at the end. */
6530 if (constructor_fields == 0)
6531 constructor_type = 0;
6532 else
6533 {
6534 constructor_type = TREE_TYPE (constructor_fields);
6535 push_member_name (constructor_fields);
6536 constructor_depth++;
6537 }
6538 }
6539 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6540 {
6541 constructor_type = TREE_TYPE (constructor_type);
6542 push_array_bounds (tree_low_cst (constructor_index, 1));
6543 constructor_depth++;
6544 }
6545
6546 if (constructor_type == 0)
6547 {
6548 error_init ("extra brace group at end of initializer");
6549 constructor_fields = 0;
6550 constructor_unfilled_fields = 0;
6551 return;
6552 }
6553
6554 if (value && TREE_CODE (value) == CONSTRUCTOR)
6555 {
6556 constructor_constant = TREE_CONSTANT (value);
6557 constructor_simple = TREE_STATIC (value);
6558 constructor_nonconst = CONSTRUCTOR_NON_CONST (value);
6559 constructor_elements = CONSTRUCTOR_ELTS (value);
6560 if (!VEC_empty (constructor_elt, constructor_elements)
6561 && (TREE_CODE (constructor_type) == RECORD_TYPE
6562 || TREE_CODE (constructor_type) == ARRAY_TYPE))
6563 set_nonincremental_init (braced_init_obstack);
6564 }
6565
6566 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
6567 {
6568 missing_braces_mentioned = 1;
6569 warning_init (OPT_Wmissing_braces, "missing braces around initializer");
6570 }
6571
6572 if (TREE_CODE (constructor_type) == RECORD_TYPE
6573 || TREE_CODE (constructor_type) == UNION_TYPE)
6574 {
6575 constructor_fields = TYPE_FIELDS (constructor_type);
6576 /* Skip any nameless bit fields at the beginning. */
6577 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
6578 && DECL_NAME (constructor_fields) == 0)
6579 constructor_fields = TREE_CHAIN (constructor_fields);
6580
6581 constructor_unfilled_fields = constructor_fields;
6582 constructor_bit_index = bitsize_zero_node;
6583 }
6584 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6585 {
6586 /* Vectors are like simple fixed-size arrays. */
6587 constructor_max_index =
6588 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
6589 constructor_index = convert (bitsizetype, integer_zero_node);
6590 constructor_unfilled_index = constructor_index;
6591 }
6592 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6593 {
6594 if (TYPE_DOMAIN (constructor_type))
6595 {
6596 constructor_max_index
6597 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
6598
6599 /* Detect non-empty initializations of zero-length arrays. */
6600 if (constructor_max_index == NULL_TREE
6601 && TYPE_SIZE (constructor_type))
6602 constructor_max_index = build_int_cst (NULL_TREE, -1);
6603
6604 /* constructor_max_index needs to be an INTEGER_CST. Attempts
6605 to initialize VLAs will cause a proper error; avoid tree
6606 checking errors as well by setting a safe value. */
6607 if (constructor_max_index
6608 && TREE_CODE (constructor_max_index) != INTEGER_CST)
6609 constructor_max_index = build_int_cst (NULL_TREE, -1);
6610
6611 constructor_index
6612 = convert (bitsizetype,
6613 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
6614 }
6615 else
6616 constructor_index = bitsize_zero_node;
6617
6618 constructor_unfilled_index = constructor_index;
6619 if (value && TREE_CODE (value) == STRING_CST)
6620 {
6621 /* We need to split the char/wchar array into individual
6622 characters, so that we don't have to special case it
6623 everywhere. */
6624 set_nonincremental_init_from_string (value, braced_init_obstack);
6625 }
6626 }
6627 else
6628 {
6629 if (constructor_type != error_mark_node)
6630 warning_init (0, "braces around scalar initializer");
6631 constructor_fields = constructor_type;
6632 constructor_unfilled_fields = constructor_type;
6633 }
6634 }
6635
6636 /* At the end of an implicit or explicit brace level,
6637 finish up that level of constructor. If a single expression
6638 with redundant braces initialized that level, return the
6639 c_expr structure for that expression. Otherwise, the original_code
6640 element is set to ERROR_MARK.
6641 If we were outputting the elements as they are read, return 0 as the value
6642 from inner levels (process_init_element ignores that),
6643 but return error_mark_node as the value from the outermost level
6644 (that's what we want to put in DECL_INITIAL).
6645 Otherwise, return a CONSTRUCTOR expression as the value. */
6646
6647 struct c_expr
6648 pop_init_level (int implicit, struct obstack * braced_init_obstack)
6649 {
6650 struct constructor_stack *p;
6651 struct c_expr ret;
6652 ret.value = 0;
6653 ret.original_code = ERROR_MARK;
6654 ret.original_type = NULL;
6655
6656 if (implicit == 0)
6657 {
6658 /* When we come to an explicit close brace,
6659 pop any inner levels that didn't have explicit braces. */
6660 while (constructor_stack->implicit)
6661 {
6662 process_init_element (pop_init_level (1, braced_init_obstack),
6663 true, braced_init_obstack);
6664 }
6665 gcc_assert (!constructor_range_stack);
6666 }
6667
6668 /* Now output all pending elements. */
6669 constructor_incremental = 1;
6670 output_pending_init_elements (1, braced_init_obstack);
6671
6672 p = constructor_stack;
6673
6674 /* Error for initializing a flexible array member, or a zero-length
6675 array member in an inappropriate context. */
6676 if (constructor_type && constructor_fields
6677 && TREE_CODE (constructor_type) == ARRAY_TYPE
6678 && TYPE_DOMAIN (constructor_type)
6679 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
6680 {
6681 /* Silently discard empty initializations. The parser will
6682 already have pedwarned for empty brackets. */
6683 if (integer_zerop (constructor_unfilled_index))
6684 constructor_type = NULL_TREE;
6685 else
6686 {
6687 gcc_assert (!TYPE_SIZE (constructor_type));
6688
6689 if (constructor_depth > 2)
6690 error_init ("initialization of flexible array member in a nested context");
6691 else
6692 pedwarn_init (input_location, OPT_pedantic,
6693 "initialization of a flexible array member");
6694
6695 /* We have already issued an error message for the existence
6696 of a flexible array member not at the end of the structure.
6697 Discard the initializer so that we do not die later. */
6698 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
6699 constructor_type = NULL_TREE;
6700 }
6701 }
6702
6703 /* Warn when some struct elements are implicitly initialized to zero. */
6704 if (warn_missing_field_initializers
6705 && constructor_type
6706 && TREE_CODE (constructor_type) == RECORD_TYPE
6707 && constructor_unfilled_fields)
6708 {
6709 /* Do not warn for flexible array members or zero-length arrays. */
6710 while (constructor_unfilled_fields
6711 && (!DECL_SIZE (constructor_unfilled_fields)
6712 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
6713 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
6714
6715 /* Do not warn if this level of the initializer uses member
6716 designators; it is likely to be deliberate. */
6717 if (constructor_unfilled_fields && !constructor_designated)
6718 {
6719 push_member_name (constructor_unfilled_fields);
6720 warning_init (OPT_Wmissing_field_initializers,
6721 "missing initializer");
6722 RESTORE_SPELLING_DEPTH (constructor_depth);
6723 }
6724 }
6725
6726 /* Pad out the end of the structure. */
6727 if (p->replacement_value.value)
6728 /* If this closes a superfluous brace pair,
6729 just pass out the element between them. */
6730 ret = p->replacement_value;
6731 else if (constructor_type == 0)
6732 ;
6733 else if (TREE_CODE (constructor_type) != RECORD_TYPE
6734 && TREE_CODE (constructor_type) != UNION_TYPE
6735 && TREE_CODE (constructor_type) != ARRAY_TYPE
6736 && TREE_CODE (constructor_type) != VECTOR_TYPE)
6737 {
6738 /* A nonincremental scalar initializer--just return
6739 the element, after verifying there is just one. */
6740 if (VEC_empty (constructor_elt,constructor_elements))
6741 {
6742 if (!constructor_erroneous)
6743 error_init ("empty scalar initializer");
6744 ret.value = error_mark_node;
6745 }
6746 else if (VEC_length (constructor_elt,constructor_elements) != 1)
6747 {
6748 error_init ("extra elements in scalar initializer");
6749 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
6750 }
6751 else
6752 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
6753 }
6754 else
6755 {
6756 if (constructor_erroneous)
6757 ret.value = error_mark_node;
6758 else
6759 {
6760 ret.value = build_constructor (constructor_type,
6761 constructor_elements);
6762 if (constructor_constant)
6763 TREE_CONSTANT (ret.value) = 1;
6764 if (constructor_constant && constructor_simple)
6765 TREE_STATIC (ret.value) = 1;
6766 if (constructor_nonconst)
6767 CONSTRUCTOR_NON_CONST (ret.value) = 1;
6768 }
6769 }
6770
6771 if (ret.value && TREE_CODE (ret.value) != CONSTRUCTOR)
6772 {
6773 if (constructor_nonconst)
6774 ret.original_code = C_MAYBE_CONST_EXPR;
6775 else if (ret.original_code == C_MAYBE_CONST_EXPR)
6776 ret.original_code = ERROR_MARK;
6777 }
6778
6779 constructor_type = p->type;
6780 constructor_fields = p->fields;
6781 constructor_index = p->index;
6782 constructor_max_index = p->max_index;
6783 constructor_unfilled_index = p->unfilled_index;
6784 constructor_unfilled_fields = p->unfilled_fields;
6785 constructor_bit_index = p->bit_index;
6786 constructor_elements = p->elements;
6787 constructor_constant = p->constant;
6788 constructor_simple = p->simple;
6789 constructor_nonconst = p->nonconst;
6790 constructor_erroneous = p->erroneous;
6791 constructor_incremental = p->incremental;
6792 constructor_designated = p->designated;
6793 constructor_pending_elts = p->pending_elts;
6794 constructor_depth = p->depth;
6795 if (!p->implicit)
6796 constructor_range_stack = p->range_stack;
6797 RESTORE_SPELLING_DEPTH (constructor_depth);
6798
6799 constructor_stack = p->next;
6800 free (p);
6801
6802 if (ret.value == 0 && constructor_stack == 0)
6803 ret.value = error_mark_node;
6804 return ret;
6805 }
6806
6807 /* Common handling for both array range and field name designators.
6808 ARRAY argument is nonzero for array ranges. Returns zero for success. */
6809
6810 static int
6811 set_designator (int array, struct obstack * braced_init_obstack)
6812 {
6813 tree subtype;
6814 enum tree_code subcode;
6815
6816 /* Don't die if an entire brace-pair level is superfluous
6817 in the containing level. */
6818 if (constructor_type == 0)
6819 return 1;
6820
6821 /* If there were errors in this designator list already, bail out
6822 silently. */
6823 if (designator_erroneous)
6824 return 1;
6825
6826 if (!designator_depth)
6827 {
6828 gcc_assert (!constructor_range_stack);
6829
6830 /* Designator list starts at the level of closest explicit
6831 braces. */
6832 while (constructor_stack->implicit)
6833 {
6834 process_init_element (pop_init_level (1, braced_init_obstack),
6835 true, braced_init_obstack);
6836 }
6837 constructor_designated = 1;
6838 return 0;
6839 }
6840
6841 switch (TREE_CODE (constructor_type))
6842 {
6843 case RECORD_TYPE:
6844 case UNION_TYPE:
6845 subtype = TREE_TYPE (constructor_fields);
6846 if (subtype != error_mark_node)
6847 subtype = TYPE_MAIN_VARIANT (subtype);
6848 break;
6849 case ARRAY_TYPE:
6850 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6851 break;
6852 default:
6853 gcc_unreachable ();
6854 }
6855
6856 subcode = TREE_CODE (subtype);
6857 if (array && subcode != ARRAY_TYPE)
6858 {
6859 error_init ("array index in non-array initializer");
6860 return 1;
6861 }
6862 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
6863 {
6864 error_init ("field name not in record or union initializer");
6865 return 1;
6866 }
6867
6868 constructor_designated = 1;
6869 push_init_level (2, braced_init_obstack);
6870 return 0;
6871 }
6872
6873 /* If there are range designators in designator list, push a new designator
6874 to constructor_range_stack. RANGE_END is end of such stack range or
6875 NULL_TREE if there is no range designator at this level. */
6876
6877 static void
6878 push_range_stack (tree range_end, struct obstack * braced_init_obstack)
6879 {
6880 struct constructor_range_stack *p;
6881
6882 p = (struct constructor_range_stack *)
6883 obstack_alloc (braced_init_obstack,
6884 sizeof (struct constructor_range_stack));
6885 p->prev = constructor_range_stack;
6886 p->next = 0;
6887 p->fields = constructor_fields;
6888 p->range_start = constructor_index;
6889 p->index = constructor_index;
6890 p->stack = constructor_stack;
6891 p->range_end = range_end;
6892 if (constructor_range_stack)
6893 constructor_range_stack->next = p;
6894 constructor_range_stack = p;
6895 }
6896
6897 /* Within an array initializer, specify the next index to be initialized.
6898 FIRST is that index. If LAST is nonzero, then initialize a range
6899 of indices, running from FIRST through LAST. */
6900
6901 void
6902 set_init_index (tree first, tree last,
6903 struct obstack * braced_init_obstack)
6904 {
6905 if (set_designator (1, braced_init_obstack))
6906 return;
6907
6908 designator_erroneous = 1;
6909
6910 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
6911 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
6912 {
6913 error_init ("array index in initializer not of integer type");
6914 return;
6915 }
6916
6917 if (TREE_CODE (first) != INTEGER_CST)
6918 {
6919 first = c_fully_fold (first, false, NULL);
6920 if (TREE_CODE (first) == INTEGER_CST)
6921 pedwarn_init (input_location, OPT_pedantic,
6922 "array index in initializer is not "
6923 "an integer constant expression");
6924 }
6925
6926 if (last && TREE_CODE (last) != INTEGER_CST)
6927 {
6928 last = c_fully_fold (last, false, NULL);
6929 if (TREE_CODE (last) == INTEGER_CST)
6930 pedwarn_init (input_location, OPT_pedantic,
6931 "array index in initializer is not "
6932 "an integer constant expression");
6933 }
6934
6935 if (TREE_CODE (first) != INTEGER_CST)
6936 error_init ("nonconstant array index in initializer");
6937 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
6938 error_init ("nonconstant array index in initializer");
6939 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
6940 error_init ("array index in non-array initializer");
6941 else if (tree_int_cst_sgn (first) == -1)
6942 error_init ("array index in initializer exceeds array bounds");
6943 else if (constructor_max_index
6944 && tree_int_cst_lt (constructor_max_index, first))
6945 error_init ("array index in initializer exceeds array bounds");
6946 else
6947 {
6948 constant_expression_warning (first);
6949 if (last)
6950 constant_expression_warning (last);
6951 constructor_index = convert (bitsizetype, first);
6952
6953 if (last)
6954 {
6955 if (tree_int_cst_equal (first, last))
6956 last = 0;
6957 else if (tree_int_cst_lt (last, first))
6958 {
6959 error_init ("empty index range in initializer");
6960 last = 0;
6961 }
6962 else
6963 {
6964 last = convert (bitsizetype, last);
6965 if (constructor_max_index != 0
6966 && tree_int_cst_lt (constructor_max_index, last))
6967 {
6968 error_init ("array index range in initializer exceeds array bounds");
6969 last = 0;
6970 }
6971 }
6972 }
6973
6974 designator_depth++;
6975 designator_erroneous = 0;
6976 if (constructor_range_stack || last)
6977 push_range_stack (last, braced_init_obstack);
6978 }
6979 }
6980
6981 /* Within a struct initializer, specify the next field to be initialized. */
6982
6983 void
6984 set_init_label (tree fieldname, struct obstack * braced_init_obstack)
6985 {
6986 tree tail;
6987
6988 if (set_designator (0, braced_init_obstack))
6989 return;
6990
6991 designator_erroneous = 1;
6992
6993 if (TREE_CODE (constructor_type) != RECORD_TYPE
6994 && TREE_CODE (constructor_type) != UNION_TYPE)
6995 {
6996 error_init ("field name not in record or union initializer");
6997 return;
6998 }
6999
7000 for (tail = TYPE_FIELDS (constructor_type); tail;
7001 tail = TREE_CHAIN (tail))
7002 {
7003 if (DECL_NAME (tail) == fieldname)
7004 break;
7005 }
7006
7007 if (tail == 0)
7008 error ("unknown field %qE specified in initializer", fieldname);
7009 else
7010 {
7011 constructor_fields = tail;
7012 designator_depth++;
7013 designator_erroneous = 0;
7014 if (constructor_range_stack)
7015 push_range_stack (NULL_TREE, braced_init_obstack);
7016 }
7017 }
7018 \f
7019 /* Add a new initializer to the tree of pending initializers. PURPOSE
7020 identifies the initializer, either array index or field in a structure.
7021 VALUE is the value of that index or field. If ORIGTYPE is not
7022 NULL_TREE, it is the original type of VALUE.
7023
7024 IMPLICIT is true if value comes from pop_init_level (1),
7025 the new initializer has been merged with the existing one
7026 and thus no warnings should be emitted about overriding an
7027 existing initializer. */
7028
7029 static void
7030 add_pending_init (tree purpose, tree value, tree origtype, bool implicit,
7031 struct obstack * braced_init_obstack)
7032 {
7033 struct init_node *p, **q, *r;
7034
7035 q = &constructor_pending_elts;
7036 p = 0;
7037
7038 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
7039 {
7040 while (*q != 0)
7041 {
7042 p = *q;
7043 if (tree_int_cst_lt (purpose, p->purpose))
7044 q = &p->left;
7045 else if (tree_int_cst_lt (p->purpose, purpose))
7046 q = &p->right;
7047 else
7048 {
7049 if (!implicit)
7050 {
7051 if (TREE_SIDE_EFFECTS (p->value))
7052 warning_init (0, "initialized field with side-effects overwritten");
7053 else if (warn_override_init)
7054 warning_init (OPT_Woverride_init, "initialized field overwritten");
7055 }
7056 p->value = value;
7057 p->origtype = origtype;
7058 return;
7059 }
7060 }
7061 }
7062 else
7063 {
7064 tree bitpos;
7065
7066 bitpos = bit_position (purpose);
7067 while (*q != NULL)
7068 {
7069 p = *q;
7070 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
7071 q = &p->left;
7072 else if (p->purpose != purpose)
7073 q = &p->right;
7074 else
7075 {
7076 if (!implicit)
7077 {
7078 if (TREE_SIDE_EFFECTS (p->value))
7079 warning_init (0, "initialized field with side-effects overwritten");
7080 else if (warn_override_init)
7081 warning_init (OPT_Woverride_init, "initialized field overwritten");
7082 }
7083 p->value = value;
7084 p->origtype = origtype;
7085 return;
7086 }
7087 }
7088 }
7089
7090 r = (struct init_node *) obstack_alloc (braced_init_obstack,
7091 sizeof (struct init_node));
7092 r->purpose = purpose;
7093 r->value = value;
7094 r->origtype = origtype;
7095
7096 *q = r;
7097 r->parent = p;
7098 r->left = 0;
7099 r->right = 0;
7100 r->balance = 0;
7101
7102 while (p)
7103 {
7104 struct init_node *s;
7105
7106 if (r == p->left)
7107 {
7108 if (p->balance == 0)
7109 p->balance = -1;
7110 else if (p->balance < 0)
7111 {
7112 if (r->balance < 0)
7113 {
7114 /* L rotation. */
7115 p->left = r->right;
7116 if (p->left)
7117 p->left->parent = p;
7118 r->right = p;
7119
7120 p->balance = 0;
7121 r->balance = 0;
7122
7123 s = p->parent;
7124 p->parent = r;
7125 r->parent = s;
7126 if (s)
7127 {
7128 if (s->left == p)
7129 s->left = r;
7130 else
7131 s->right = r;
7132 }
7133 else
7134 constructor_pending_elts = r;
7135 }
7136 else
7137 {
7138 /* LR rotation. */
7139 struct init_node *t = r->right;
7140
7141 r->right = t->left;
7142 if (r->right)
7143 r->right->parent = r;
7144 t->left = r;
7145
7146 p->left = t->right;
7147 if (p->left)
7148 p->left->parent = p;
7149 t->right = p;
7150
7151 p->balance = t->balance < 0;
7152 r->balance = -(t->balance > 0);
7153 t->balance = 0;
7154
7155 s = p->parent;
7156 p->parent = t;
7157 r->parent = t;
7158 t->parent = s;
7159 if (s)
7160 {
7161 if (s->left == p)
7162 s->left = t;
7163 else
7164 s->right = t;
7165 }
7166 else
7167 constructor_pending_elts = t;
7168 }
7169 break;
7170 }
7171 else
7172 {
7173 /* p->balance == +1; growth of left side balances the node. */
7174 p->balance = 0;
7175 break;
7176 }
7177 }
7178 else /* r == p->right */
7179 {
7180 if (p->balance == 0)
7181 /* Growth propagation from right side. */
7182 p->balance++;
7183 else if (p->balance > 0)
7184 {
7185 if (r->balance > 0)
7186 {
7187 /* R rotation. */
7188 p->right = r->left;
7189 if (p->right)
7190 p->right->parent = p;
7191 r->left = p;
7192
7193 p->balance = 0;
7194 r->balance = 0;
7195
7196 s = p->parent;
7197 p->parent = r;
7198 r->parent = s;
7199 if (s)
7200 {
7201 if (s->left == p)
7202 s->left = r;
7203 else
7204 s->right = r;
7205 }
7206 else
7207 constructor_pending_elts = r;
7208 }
7209 else /* r->balance == -1 */
7210 {
7211 /* RL rotation */
7212 struct init_node *t = r->left;
7213
7214 r->left = t->right;
7215 if (r->left)
7216 r->left->parent = r;
7217 t->right = r;
7218
7219 p->right = t->left;
7220 if (p->right)
7221 p->right->parent = p;
7222 t->left = p;
7223
7224 r->balance = (t->balance < 0);
7225 p->balance = -(t->balance > 0);
7226 t->balance = 0;
7227
7228 s = p->parent;
7229 p->parent = t;
7230 r->parent = t;
7231 t->parent = s;
7232 if (s)
7233 {
7234 if (s->left == p)
7235 s->left = t;
7236 else
7237 s->right = t;
7238 }
7239 else
7240 constructor_pending_elts = t;
7241 }
7242 break;
7243 }
7244 else
7245 {
7246 /* p->balance == -1; growth of right side balances the node. */
7247 p->balance = 0;
7248 break;
7249 }
7250 }
7251
7252 r = p;
7253 p = p->parent;
7254 }
7255 }
7256
7257 /* Build AVL tree from a sorted chain. */
7258
7259 static void
7260 set_nonincremental_init (struct obstack * braced_init_obstack)
7261 {
7262 unsigned HOST_WIDE_INT ix;
7263 tree index, value;
7264
7265 if (TREE_CODE (constructor_type) != RECORD_TYPE
7266 && TREE_CODE (constructor_type) != ARRAY_TYPE)
7267 return;
7268
7269 FOR_EACH_CONSTRUCTOR_ELT (constructor_elements, ix, index, value)
7270 {
7271 add_pending_init (index, value, NULL_TREE, false,
7272 braced_init_obstack);
7273 }
7274 constructor_elements = 0;
7275 if (TREE_CODE (constructor_type) == RECORD_TYPE)
7276 {
7277 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
7278 /* Skip any nameless bit fields at the beginning. */
7279 while (constructor_unfilled_fields != 0
7280 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
7281 && DECL_NAME (constructor_unfilled_fields) == 0)
7282 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
7283
7284 }
7285 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
7286 {
7287 if (TYPE_DOMAIN (constructor_type))
7288 constructor_unfilled_index
7289 = convert (bitsizetype,
7290 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
7291 else
7292 constructor_unfilled_index = bitsize_zero_node;
7293 }
7294 constructor_incremental = 0;
7295 }
7296
7297 /* Build AVL tree from a string constant. */
7298
7299 static void
7300 set_nonincremental_init_from_string (tree str,
7301 struct obstack * braced_init_obstack)
7302 {
7303 tree value, purpose, type;
7304 HOST_WIDE_INT val[2];
7305 const char *p, *end;
7306 int byte, wchar_bytes, charwidth, bitpos;
7307
7308 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
7309
7310 wchar_bytes = TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str))) / BITS_PER_UNIT;
7311 charwidth = TYPE_PRECISION (char_type_node);
7312 type = TREE_TYPE (constructor_type);
7313 p = TREE_STRING_POINTER (str);
7314 end = p + TREE_STRING_LENGTH (str);
7315
7316 for (purpose = bitsize_zero_node;
7317 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
7318 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
7319 {
7320 if (wchar_bytes == 1)
7321 {
7322 val[1] = (unsigned char) *p++;
7323 val[0] = 0;
7324 }
7325 else
7326 {
7327 val[0] = 0;
7328 val[1] = 0;
7329 for (byte = 0; byte < wchar_bytes; byte++)
7330 {
7331 if (BYTES_BIG_ENDIAN)
7332 bitpos = (wchar_bytes - byte - 1) * charwidth;
7333 else
7334 bitpos = byte * charwidth;
7335 val[bitpos < HOST_BITS_PER_WIDE_INT]
7336 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
7337 << (bitpos % HOST_BITS_PER_WIDE_INT);
7338 }
7339 }
7340
7341 if (!TYPE_UNSIGNED (type))
7342 {
7343 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
7344 if (bitpos < HOST_BITS_PER_WIDE_INT)
7345 {
7346 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
7347 {
7348 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
7349 val[0] = -1;
7350 }
7351 }
7352 else if (bitpos == HOST_BITS_PER_WIDE_INT)
7353 {
7354 if (val[1] < 0)
7355 val[0] = -1;
7356 }
7357 else if (val[0] & (((HOST_WIDE_INT) 1)
7358 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
7359 val[0] |= ((HOST_WIDE_INT) -1)
7360 << (bitpos - HOST_BITS_PER_WIDE_INT);
7361 }
7362
7363 value = build_int_cst_wide (type, val[1], val[0]);
7364 add_pending_init (purpose, value, NULL_TREE, false,
7365 braced_init_obstack);
7366 }
7367
7368 constructor_incremental = 0;
7369 }
7370
7371 /* Return value of FIELD in pending initializer or zero if the field was
7372 not initialized yet. */
7373
7374 static tree
7375 find_init_member (tree field, struct obstack * braced_init_obstack)
7376 {
7377 struct init_node *p;
7378
7379 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
7380 {
7381 if (constructor_incremental
7382 && tree_int_cst_lt (field, constructor_unfilled_index))
7383 set_nonincremental_init (braced_init_obstack);
7384
7385 p = constructor_pending_elts;
7386 while (p)
7387 {
7388 if (tree_int_cst_lt (field, p->purpose))
7389 p = p->left;
7390 else if (tree_int_cst_lt (p->purpose, field))
7391 p = p->right;
7392 else
7393 return p->value;
7394 }
7395 }
7396 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
7397 {
7398 tree bitpos = bit_position (field);
7399
7400 if (constructor_incremental
7401 && (!constructor_unfilled_fields
7402 || tree_int_cst_lt (bitpos,
7403 bit_position (constructor_unfilled_fields))))
7404 set_nonincremental_init (braced_init_obstack);
7405
7406 p = constructor_pending_elts;
7407 while (p)
7408 {
7409 if (field == p->purpose)
7410 return p->value;
7411 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
7412 p = p->left;
7413 else
7414 p = p->right;
7415 }
7416 }
7417 else if (TREE_CODE (constructor_type) == UNION_TYPE)
7418 {
7419 if (!VEC_empty (constructor_elt, constructor_elements)
7420 && (VEC_last (constructor_elt, constructor_elements)->index
7421 == field))
7422 return VEC_last (constructor_elt, constructor_elements)->value;
7423 }
7424 return 0;
7425 }
7426
7427 /* "Output" the next constructor element.
7428 At top level, really output it to assembler code now.
7429 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
7430 If ORIGTYPE is not NULL_TREE, it is the original type of VALUE.
7431 TYPE is the data type that the containing data type wants here.
7432 FIELD is the field (a FIELD_DECL) or the index that this element fills.
7433 If VALUE is a string constant, STRICT_STRING is true if it is
7434 unparenthesized or we should not warn here for it being parenthesized.
7435 For other types of VALUE, STRICT_STRING is not used.
7436
7437 PENDING if non-nil means output pending elements that belong
7438 right after this element. (PENDING is normally 1;
7439 it is 0 while outputting pending elements, to avoid recursion.)
7440
7441 IMPLICIT is true if value comes from pop_init_level (1),
7442 the new initializer has been merged with the existing one
7443 and thus no warnings should be emitted about overriding an
7444 existing initializer. */
7445
7446 static void
7447 output_init_element (tree value, tree origtype, bool strict_string, tree type,
7448 tree field, int pending, bool implicit,
7449 struct obstack * braced_init_obstack)
7450 {
7451 tree semantic_type = NULL_TREE;
7452 constructor_elt *celt;
7453 bool maybe_const = true;
7454 bool npc;
7455
7456 if (type == error_mark_node || value == error_mark_node)
7457 {
7458 constructor_erroneous = 1;
7459 return;
7460 }
7461 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
7462 && (TREE_CODE (value) == STRING_CST
7463 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR)
7464 && !(TREE_CODE (value) == STRING_CST
7465 && TREE_CODE (type) == ARRAY_TYPE
7466 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
7467 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
7468 TYPE_MAIN_VARIANT (type)))
7469 value = array_to_pointer_conversion (input_location, value);
7470
7471 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
7472 && require_constant_value && !flag_isoc99 && pending)
7473 {
7474 /* As an extension, allow initializing objects with static storage
7475 duration with compound literals (which are then treated just as
7476 the brace enclosed list they contain). */
7477 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
7478 value = DECL_INITIAL (decl);
7479 }
7480
7481 npc = null_pointer_constant_p (value);
7482 if (TREE_CODE (value) == EXCESS_PRECISION_EXPR)
7483 {
7484 semantic_type = TREE_TYPE (value);
7485 value = TREE_OPERAND (value, 0);
7486 }
7487 value = c_fully_fold (value, require_constant_value, &maybe_const);
7488
7489 if (value == error_mark_node)
7490 constructor_erroneous = 1;
7491 else if (!TREE_CONSTANT (value))
7492 constructor_constant = 0;
7493 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
7494 || ((TREE_CODE (constructor_type) == RECORD_TYPE
7495 || TREE_CODE (constructor_type) == UNION_TYPE)
7496 && DECL_C_BIT_FIELD (field)
7497 && TREE_CODE (value) != INTEGER_CST))
7498 constructor_simple = 0;
7499 if (!maybe_const)
7500 constructor_nonconst = 1;
7501
7502 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
7503 {
7504 if (require_constant_value)
7505 {
7506 error_init ("initializer element is not constant");
7507 value = error_mark_node;
7508 }
7509 else if (require_constant_elements)
7510 pedwarn (input_location, 0,
7511 "initializer element is not computable at load time");
7512 }
7513 else if (!maybe_const
7514 && (require_constant_value || require_constant_elements))
7515 pedwarn_init (input_location, 0,
7516 "initializer element is not a constant expression");
7517
7518 /* Issue -Wc++-compat warnings about initializing a bitfield with
7519 enum type. */
7520 if (warn_cxx_compat
7521 && field != NULL_TREE
7522 && TREE_CODE (field) == FIELD_DECL
7523 && DECL_BIT_FIELD_TYPE (field) != NULL_TREE
7524 && (TYPE_MAIN_VARIANT (DECL_BIT_FIELD_TYPE (field))
7525 != TYPE_MAIN_VARIANT (type))
7526 && TREE_CODE (DECL_BIT_FIELD_TYPE (field)) == ENUMERAL_TYPE)
7527 {
7528 tree checktype = origtype != NULL_TREE ? origtype : TREE_TYPE (value);
7529 if (checktype != error_mark_node
7530 && (TYPE_MAIN_VARIANT (checktype)
7531 != TYPE_MAIN_VARIANT (DECL_BIT_FIELD_TYPE (field))))
7532 warning_init (OPT_Wc___compat,
7533 "enum conversion in initialization is invalid in C++");
7534 }
7535
7536 /* If this field is empty (and not at the end of structure),
7537 don't do anything other than checking the initializer. */
7538 if (field
7539 && (TREE_TYPE (field) == error_mark_node
7540 || (COMPLETE_TYPE_P (TREE_TYPE (field))
7541 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
7542 && (TREE_CODE (constructor_type) == ARRAY_TYPE
7543 || TREE_CHAIN (field)))))
7544 return;
7545
7546 if (semantic_type)
7547 value = build1 (EXCESS_PRECISION_EXPR, semantic_type, value);
7548 value = digest_init (input_location, type, value, origtype, npc,
7549 strict_string, require_constant_value);
7550 if (value == error_mark_node)
7551 {
7552 constructor_erroneous = 1;
7553 return;
7554 }
7555 if (require_constant_value || require_constant_elements)
7556 constant_expression_warning (value);
7557
7558 /* If this element doesn't come next in sequence,
7559 put it on constructor_pending_elts. */
7560 if (TREE_CODE (constructor_type) == ARRAY_TYPE
7561 && (!constructor_incremental
7562 || !tree_int_cst_equal (field, constructor_unfilled_index)))
7563 {
7564 if (constructor_incremental
7565 && tree_int_cst_lt (field, constructor_unfilled_index))
7566 set_nonincremental_init (braced_init_obstack);
7567
7568 add_pending_init (field, value, origtype, implicit,
7569 braced_init_obstack);
7570 return;
7571 }
7572 else if (TREE_CODE (constructor_type) == RECORD_TYPE
7573 && (!constructor_incremental
7574 || field != constructor_unfilled_fields))
7575 {
7576 /* We do this for records but not for unions. In a union,
7577 no matter which field is specified, it can be initialized
7578 right away since it starts at the beginning of the union. */
7579 if (constructor_incremental)
7580 {
7581 if (!constructor_unfilled_fields)
7582 set_nonincremental_init (braced_init_obstack);
7583 else
7584 {
7585 tree bitpos, unfillpos;
7586
7587 bitpos = bit_position (field);
7588 unfillpos = bit_position (constructor_unfilled_fields);
7589
7590 if (tree_int_cst_lt (bitpos, unfillpos))
7591 set_nonincremental_init (braced_init_obstack);
7592 }
7593 }
7594
7595 add_pending_init (field, value, origtype, implicit,
7596 braced_init_obstack);
7597 return;
7598 }
7599 else if (TREE_CODE (constructor_type) == UNION_TYPE
7600 && !VEC_empty (constructor_elt, constructor_elements))
7601 {
7602 if (!implicit)
7603 {
7604 if (TREE_SIDE_EFFECTS (VEC_last (constructor_elt,
7605 constructor_elements)->value))
7606 warning_init (0,
7607 "initialized field with side-effects overwritten");
7608 else if (warn_override_init)
7609 warning_init (OPT_Woverride_init, "initialized field overwritten");
7610 }
7611
7612 /* We can have just one union field set. */
7613 constructor_elements = 0;
7614 }
7615
7616 /* Otherwise, output this element either to
7617 constructor_elements or to the assembler file. */
7618
7619 celt = VEC_safe_push (constructor_elt, gc, constructor_elements, NULL);
7620 celt->index = field;
7621 celt->value = value;
7622
7623 /* Advance the variable that indicates sequential elements output. */
7624 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
7625 constructor_unfilled_index
7626 = size_binop_loc (input_location, PLUS_EXPR, constructor_unfilled_index,
7627 bitsize_one_node);
7628 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
7629 {
7630 constructor_unfilled_fields
7631 = TREE_CHAIN (constructor_unfilled_fields);
7632
7633 /* Skip any nameless bit fields. */
7634 while (constructor_unfilled_fields != 0
7635 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
7636 && DECL_NAME (constructor_unfilled_fields) == 0)
7637 constructor_unfilled_fields =
7638 TREE_CHAIN (constructor_unfilled_fields);
7639 }
7640 else if (TREE_CODE (constructor_type) == UNION_TYPE)
7641 constructor_unfilled_fields = 0;
7642
7643 /* Now output any pending elements which have become next. */
7644 if (pending)
7645 output_pending_init_elements (0, braced_init_obstack);
7646 }
7647
7648 /* Output any pending elements which have become next.
7649 As we output elements, constructor_unfilled_{fields,index}
7650 advances, which may cause other elements to become next;
7651 if so, they too are output.
7652
7653 If ALL is 0, we return when there are
7654 no more pending elements to output now.
7655
7656 If ALL is 1, we output space as necessary so that
7657 we can output all the pending elements. */
7658 static void
7659 output_pending_init_elements (int all, struct obstack * braced_init_obstack)
7660 {
7661 struct init_node *elt = constructor_pending_elts;
7662 tree next;
7663
7664 retry:
7665
7666 /* Look through the whole pending tree.
7667 If we find an element that should be output now,
7668 output it. Otherwise, set NEXT to the element
7669 that comes first among those still pending. */
7670
7671 next = 0;
7672 while (elt)
7673 {
7674 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
7675 {
7676 if (tree_int_cst_equal (elt->purpose,
7677 constructor_unfilled_index))
7678 output_init_element (elt->value, elt->origtype, true,
7679 TREE_TYPE (constructor_type),
7680 constructor_unfilled_index, 0, false,
7681 braced_init_obstack);
7682 else if (tree_int_cst_lt (constructor_unfilled_index,
7683 elt->purpose))
7684 {
7685 /* Advance to the next smaller node. */
7686 if (elt->left)
7687 elt = elt->left;
7688 else
7689 {
7690 /* We have reached the smallest node bigger than the
7691 current unfilled index. Fill the space first. */
7692 next = elt->purpose;
7693 break;
7694 }
7695 }
7696 else
7697 {
7698 /* Advance to the next bigger node. */
7699 if (elt->right)
7700 elt = elt->right;
7701 else
7702 {
7703 /* We have reached the biggest node in a subtree. Find
7704 the parent of it, which is the next bigger node. */
7705 while (elt->parent && elt->parent->right == elt)
7706 elt = elt->parent;
7707 elt = elt->parent;
7708 if (elt && tree_int_cst_lt (constructor_unfilled_index,
7709 elt->purpose))
7710 {
7711 next = elt->purpose;
7712 break;
7713 }
7714 }
7715 }
7716 }
7717 else if (TREE_CODE (constructor_type) == RECORD_TYPE
7718 || TREE_CODE (constructor_type) == UNION_TYPE)
7719 {
7720 tree ctor_unfilled_bitpos, elt_bitpos;
7721
7722 /* If the current record is complete we are done. */
7723 if (constructor_unfilled_fields == 0)
7724 break;
7725
7726 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
7727 elt_bitpos = bit_position (elt->purpose);
7728 /* We can't compare fields here because there might be empty
7729 fields in between. */
7730 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
7731 {
7732 constructor_unfilled_fields = elt->purpose;
7733 output_init_element (elt->value, elt->origtype, true,
7734 TREE_TYPE (elt->purpose),
7735 elt->purpose, 0, false,
7736 braced_init_obstack);
7737 }
7738 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
7739 {
7740 /* Advance to the next smaller node. */
7741 if (elt->left)
7742 elt = elt->left;
7743 else
7744 {
7745 /* We have reached the smallest node bigger than the
7746 current unfilled field. Fill the space first. */
7747 next = elt->purpose;
7748 break;
7749 }
7750 }
7751 else
7752 {
7753 /* Advance to the next bigger node. */
7754 if (elt->right)
7755 elt = elt->right;
7756 else
7757 {
7758 /* We have reached the biggest node in a subtree. Find
7759 the parent of it, which is the next bigger node. */
7760 while (elt->parent && elt->parent->right == elt)
7761 elt = elt->parent;
7762 elt = elt->parent;
7763 if (elt
7764 && (tree_int_cst_lt (ctor_unfilled_bitpos,
7765 bit_position (elt->purpose))))
7766 {
7767 next = elt->purpose;
7768 break;
7769 }
7770 }
7771 }
7772 }
7773 }
7774
7775 /* Ordinarily return, but not if we want to output all
7776 and there are elements left. */
7777 if (!(all && next != 0))
7778 return;
7779
7780 /* If it's not incremental, just skip over the gap, so that after
7781 jumping to retry we will output the next successive element. */
7782 if (TREE_CODE (constructor_type) == RECORD_TYPE
7783 || TREE_CODE (constructor_type) == UNION_TYPE)
7784 constructor_unfilled_fields = next;
7785 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
7786 constructor_unfilled_index = next;
7787
7788 /* ELT now points to the node in the pending tree with the next
7789 initializer to output. */
7790 goto retry;
7791 }
7792 \f
7793 /* Add one non-braced element to the current constructor level.
7794 This adjusts the current position within the constructor's type.
7795 This may also start or terminate implicit levels
7796 to handle a partly-braced initializer.
7797
7798 Once this has found the correct level for the new element,
7799 it calls output_init_element.
7800
7801 IMPLICIT is true if value comes from pop_init_level (1),
7802 the new initializer has been merged with the existing one
7803 and thus no warnings should be emitted about overriding an
7804 existing initializer. */
7805
7806 void
7807 process_init_element (struct c_expr value, bool implicit,
7808 struct obstack * braced_init_obstack)
7809 {
7810 tree orig_value = value.value;
7811 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
7812 bool strict_string = value.original_code == STRING_CST;
7813
7814 designator_depth = 0;
7815 designator_erroneous = 0;
7816
7817 /* Handle superfluous braces around string cst as in
7818 char x[] = {"foo"}; */
7819 if (string_flag
7820 && constructor_type
7821 && TREE_CODE (constructor_type) == ARRAY_TYPE
7822 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
7823 && integer_zerop (constructor_unfilled_index))
7824 {
7825 if (constructor_stack->replacement_value.value)
7826 error_init ("excess elements in char array initializer");
7827 constructor_stack->replacement_value = value;
7828 return;
7829 }
7830
7831 if (constructor_stack->replacement_value.value != 0)
7832 {
7833 error_init ("excess elements in struct initializer");
7834 return;
7835 }
7836
7837 /* Ignore elements of a brace group if it is entirely superfluous
7838 and has already been diagnosed. */
7839 if (constructor_type == 0)
7840 return;
7841
7842 /* If we've exhausted any levels that didn't have braces,
7843 pop them now. */
7844 while (constructor_stack->implicit)
7845 {
7846 if ((TREE_CODE (constructor_type) == RECORD_TYPE
7847 || TREE_CODE (constructor_type) == UNION_TYPE)
7848 && constructor_fields == 0)
7849 process_init_element (pop_init_level (1, braced_init_obstack),
7850 true, braced_init_obstack);
7851 else if ((TREE_CODE (constructor_type) == ARRAY_TYPE
7852 || TREE_CODE (constructor_type) == VECTOR_TYPE)
7853 && (constructor_max_index == 0
7854 || tree_int_cst_lt (constructor_max_index,
7855 constructor_index)))
7856 process_init_element (pop_init_level (1, braced_init_obstack),
7857 true, braced_init_obstack);
7858 else
7859 break;
7860 }
7861
7862 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
7863 if (constructor_range_stack)
7864 {
7865 /* If value is a compound literal and we'll be just using its
7866 content, don't put it into a SAVE_EXPR. */
7867 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
7868 || !require_constant_value
7869 || flag_isoc99)
7870 {
7871 tree semantic_type = NULL_TREE;
7872 if (TREE_CODE (value.value) == EXCESS_PRECISION_EXPR)
7873 {
7874 semantic_type = TREE_TYPE (value.value);
7875 value.value = TREE_OPERAND (value.value, 0);
7876 }
7877 value.value = c_save_expr (value.value);
7878 if (semantic_type)
7879 value.value = build1 (EXCESS_PRECISION_EXPR, semantic_type,
7880 value.value);
7881 }
7882 }
7883
7884 while (1)
7885 {
7886 if (TREE_CODE (constructor_type) == RECORD_TYPE)
7887 {
7888 tree fieldtype;
7889 enum tree_code fieldcode;
7890
7891 if (constructor_fields == 0)
7892 {
7893 pedwarn_init (input_location, 0,
7894 "excess elements in struct initializer");
7895 break;
7896 }
7897
7898 fieldtype = TREE_TYPE (constructor_fields);
7899 if (fieldtype != error_mark_node)
7900 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
7901 fieldcode = TREE_CODE (fieldtype);
7902
7903 /* Error for non-static initialization of a flexible array member. */
7904 if (fieldcode == ARRAY_TYPE
7905 && !require_constant_value
7906 && TYPE_SIZE (fieldtype) == NULL_TREE
7907 && TREE_CHAIN (constructor_fields) == NULL_TREE)
7908 {
7909 error_init ("non-static initialization of a flexible array member");
7910 break;
7911 }
7912
7913 /* Accept a string constant to initialize a subarray. */
7914 if (value.value != 0
7915 && fieldcode == ARRAY_TYPE
7916 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
7917 && string_flag)
7918 value.value = orig_value;
7919 /* Otherwise, if we have come to a subaggregate,
7920 and we don't have an element of its type, push into it. */
7921 else if (value.value != 0
7922 && value.value != error_mark_node
7923 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
7924 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
7925 || fieldcode == UNION_TYPE || fieldcode == VECTOR_TYPE))
7926 {
7927 push_init_level (1, braced_init_obstack);
7928 continue;
7929 }
7930
7931 if (value.value)
7932 {
7933 push_member_name (constructor_fields);
7934 output_init_element (value.value, value.original_type,
7935 strict_string, fieldtype,
7936 constructor_fields, 1, implicit,
7937 braced_init_obstack);
7938 RESTORE_SPELLING_DEPTH (constructor_depth);
7939 }
7940 else
7941 /* Do the bookkeeping for an element that was
7942 directly output as a constructor. */
7943 {
7944 /* For a record, keep track of end position of last field. */
7945 if (DECL_SIZE (constructor_fields))
7946 constructor_bit_index
7947 = size_binop_loc (input_location, PLUS_EXPR,
7948 bit_position (constructor_fields),
7949 DECL_SIZE (constructor_fields));
7950
7951 /* If the current field was the first one not yet written out,
7952 it isn't now, so update. */
7953 if (constructor_unfilled_fields == constructor_fields)
7954 {
7955 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
7956 /* Skip any nameless bit fields. */
7957 while (constructor_unfilled_fields != 0
7958 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
7959 && DECL_NAME (constructor_unfilled_fields) == 0)
7960 constructor_unfilled_fields =
7961 TREE_CHAIN (constructor_unfilled_fields);
7962 }
7963 }
7964
7965 constructor_fields = TREE_CHAIN (constructor_fields);
7966 /* Skip any nameless bit fields at the beginning. */
7967 while (constructor_fields != 0
7968 && DECL_C_BIT_FIELD (constructor_fields)
7969 && DECL_NAME (constructor_fields) == 0)
7970 constructor_fields = TREE_CHAIN (constructor_fields);
7971 }
7972 else if (TREE_CODE (constructor_type) == UNION_TYPE)
7973 {
7974 tree fieldtype;
7975 enum tree_code fieldcode;
7976
7977 if (constructor_fields == 0)
7978 {
7979 pedwarn_init (input_location, 0,
7980 "excess elements in union initializer");
7981 break;
7982 }
7983
7984 fieldtype = TREE_TYPE (constructor_fields);
7985 if (fieldtype != error_mark_node)
7986 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
7987 fieldcode = TREE_CODE (fieldtype);
7988
7989 /* Warn that traditional C rejects initialization of unions.
7990 We skip the warning if the value is zero. This is done
7991 under the assumption that the zero initializer in user
7992 code appears conditioned on e.g. __STDC__ to avoid
7993 "missing initializer" warnings and relies on default
7994 initialization to zero in the traditional C case.
7995 We also skip the warning if the initializer is designated,
7996 again on the assumption that this must be conditional on
7997 __STDC__ anyway (and we've already complained about the
7998 member-designator already). */
7999 if (!in_system_header && !constructor_designated
8000 && !(value.value && (integer_zerop (value.value)
8001 || real_zerop (value.value))))
8002 warning (OPT_Wtraditional, "traditional C rejects initialization "
8003 "of unions");
8004
8005 /* Accept a string constant to initialize a subarray. */
8006 if (value.value != 0
8007 && fieldcode == ARRAY_TYPE
8008 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
8009 && string_flag)
8010 value.value = orig_value;
8011 /* Otherwise, if we have come to a subaggregate,
8012 and we don't have an element of its type, push into it. */
8013 else if (value.value != 0
8014 && value.value != error_mark_node
8015 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
8016 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
8017 || fieldcode == UNION_TYPE || fieldcode == VECTOR_TYPE))
8018 {
8019 push_init_level (1, braced_init_obstack);
8020 continue;
8021 }
8022
8023 if (value.value)
8024 {
8025 push_member_name (constructor_fields);
8026 output_init_element (value.value, value.original_type,
8027 strict_string, fieldtype,
8028 constructor_fields, 1, implicit,
8029 braced_init_obstack);
8030 RESTORE_SPELLING_DEPTH (constructor_depth);
8031 }
8032 else
8033 /* Do the bookkeeping for an element that was
8034 directly output as a constructor. */
8035 {
8036 constructor_bit_index = DECL_SIZE (constructor_fields);
8037 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
8038 }
8039
8040 constructor_fields = 0;
8041 }
8042 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
8043 {
8044 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
8045 enum tree_code eltcode = TREE_CODE (elttype);
8046
8047 /* Accept a string constant to initialize a subarray. */
8048 if (value.value != 0
8049 && eltcode == ARRAY_TYPE
8050 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
8051 && string_flag)
8052 value.value = orig_value;
8053 /* Otherwise, if we have come to a subaggregate,
8054 and we don't have an element of its type, push into it. */
8055 else if (value.value != 0
8056 && value.value != error_mark_node
8057 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
8058 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
8059 || eltcode == UNION_TYPE || eltcode == VECTOR_TYPE))
8060 {
8061 push_init_level (1, braced_init_obstack);
8062 continue;
8063 }
8064
8065 if (constructor_max_index != 0
8066 && (tree_int_cst_lt (constructor_max_index, constructor_index)
8067 || integer_all_onesp (constructor_max_index)))
8068 {
8069 pedwarn_init (input_location, 0,
8070 "excess elements in array initializer");
8071 break;
8072 }
8073
8074 /* Now output the actual element. */
8075 if (value.value)
8076 {
8077 push_array_bounds (tree_low_cst (constructor_index, 1));
8078 output_init_element (value.value, value.original_type,
8079 strict_string, elttype,
8080 constructor_index, 1, implicit,
8081 braced_init_obstack);
8082 RESTORE_SPELLING_DEPTH (constructor_depth);
8083 }
8084
8085 constructor_index
8086 = size_binop_loc (input_location, PLUS_EXPR,
8087 constructor_index, bitsize_one_node);
8088
8089 if (!value.value)
8090 /* If we are doing the bookkeeping for an element that was
8091 directly output as a constructor, we must update
8092 constructor_unfilled_index. */
8093 constructor_unfilled_index = constructor_index;
8094 }
8095 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
8096 {
8097 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
8098
8099 /* Do a basic check of initializer size. Note that vectors
8100 always have a fixed size derived from their type. */
8101 if (tree_int_cst_lt (constructor_max_index, constructor_index))
8102 {
8103 pedwarn_init (input_location, 0,
8104 "excess elements in vector initializer");
8105 break;
8106 }
8107
8108 /* Now output the actual element. */
8109 if (value.value)
8110 {
8111 if (TREE_CODE (value.value) == VECTOR_CST)
8112 elttype = TYPE_MAIN_VARIANT (constructor_type);
8113 output_init_element (value.value, value.original_type,
8114 strict_string, elttype,
8115 constructor_index, 1, implicit,
8116 braced_init_obstack);
8117 }
8118
8119 constructor_index
8120 = size_binop_loc (input_location,
8121 PLUS_EXPR, constructor_index, bitsize_one_node);
8122
8123 if (!value.value)
8124 /* If we are doing the bookkeeping for an element that was
8125 directly output as a constructor, we must update
8126 constructor_unfilled_index. */
8127 constructor_unfilled_index = constructor_index;
8128 }
8129
8130 /* Handle the sole element allowed in a braced initializer
8131 for a scalar variable. */
8132 else if (constructor_type != error_mark_node
8133 && constructor_fields == 0)
8134 {
8135 pedwarn_init (input_location, 0,
8136 "excess elements in scalar initializer");
8137 break;
8138 }
8139 else
8140 {
8141 if (value.value)
8142 output_init_element (value.value, value.original_type,
8143 strict_string, constructor_type,
8144 NULL_TREE, 1, implicit,
8145 braced_init_obstack);
8146 constructor_fields = 0;
8147 }
8148
8149 /* Handle range initializers either at this level or anywhere higher
8150 in the designator stack. */
8151 if (constructor_range_stack)
8152 {
8153 struct constructor_range_stack *p, *range_stack;
8154 int finish = 0;
8155
8156 range_stack = constructor_range_stack;
8157 constructor_range_stack = 0;
8158 while (constructor_stack != range_stack->stack)
8159 {
8160 gcc_assert (constructor_stack->implicit);
8161 process_init_element (pop_init_level (1,
8162 braced_init_obstack),
8163 true, braced_init_obstack);
8164 }
8165 for (p = range_stack;
8166 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
8167 p = p->prev)
8168 {
8169 gcc_assert (constructor_stack->implicit);
8170 process_init_element (pop_init_level (1, braced_init_obstack),
8171 true, braced_init_obstack);
8172 }
8173
8174 p->index = size_binop_loc (input_location,
8175 PLUS_EXPR, p->index, bitsize_one_node);
8176 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
8177 finish = 1;
8178
8179 while (1)
8180 {
8181 constructor_index = p->index;
8182 constructor_fields = p->fields;
8183 if (finish && p->range_end && p->index == p->range_start)
8184 {
8185 finish = 0;
8186 p->prev = 0;
8187 }
8188 p = p->next;
8189 if (!p)
8190 break;
8191 push_init_level (2, braced_init_obstack);
8192 p->stack = constructor_stack;
8193 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
8194 p->index = p->range_start;
8195 }
8196
8197 if (!finish)
8198 constructor_range_stack = range_stack;
8199 continue;
8200 }
8201
8202 break;
8203 }
8204
8205 constructor_range_stack = 0;
8206 }
8207 \f
8208 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
8209 (guaranteed to be 'volatile' or null) and ARGS (represented using
8210 an ASM_EXPR node). */
8211 tree
8212 build_asm_stmt (tree cv_qualifier, tree args)
8213 {
8214 if (!ASM_VOLATILE_P (args) && cv_qualifier)
8215 ASM_VOLATILE_P (args) = 1;
8216 return add_stmt (args);
8217 }
8218
8219 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
8220 some INPUTS, and some CLOBBERS. The latter three may be NULL.
8221 SIMPLE indicates whether there was anything at all after the
8222 string in the asm expression -- asm("blah") and asm("blah" : )
8223 are subtly different. We use a ASM_EXPR node to represent this. */
8224 tree
8225 build_asm_expr (location_t loc, tree string, tree outputs, tree inputs,
8226 tree clobbers, tree labels, bool simple)
8227 {
8228 tree tail;
8229 tree args;
8230 int i;
8231 const char *constraint;
8232 const char **oconstraints;
8233 bool allows_mem, allows_reg, is_inout;
8234 int ninputs, noutputs;
8235
8236 ninputs = list_length (inputs);
8237 noutputs = list_length (outputs);
8238 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
8239
8240 string = resolve_asm_operand_names (string, outputs, inputs, labels);
8241
8242 /* Remove output conversions that change the type but not the mode. */
8243 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
8244 {
8245 tree output = TREE_VALUE (tail);
8246
8247 /* ??? Really, this should not be here. Users should be using a
8248 proper lvalue, dammit. But there's a long history of using casts
8249 in the output operands. In cases like longlong.h, this becomes a
8250 primitive form of typechecking -- if the cast can be removed, then
8251 the output operand had a type of the proper width; otherwise we'll
8252 get an error. Gross, but ... */
8253 STRIP_NOPS (output);
8254
8255 if (!lvalue_or_else (output, lv_asm))
8256 output = error_mark_node;
8257
8258 if (output != error_mark_node
8259 && (TREE_READONLY (output)
8260 || TYPE_READONLY (TREE_TYPE (output))
8261 || ((TREE_CODE (TREE_TYPE (output)) == RECORD_TYPE
8262 || TREE_CODE (TREE_TYPE (output)) == UNION_TYPE)
8263 && C_TYPE_FIELDS_READONLY (TREE_TYPE (output)))))
8264 readonly_error (output, lv_asm);
8265
8266 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
8267 oconstraints[i] = constraint;
8268
8269 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
8270 &allows_mem, &allows_reg, &is_inout))
8271 {
8272 /* If the operand is going to end up in memory,
8273 mark it addressable. */
8274 if (!allows_reg && !c_mark_addressable (output))
8275 output = error_mark_node;
8276 }
8277 else
8278 output = error_mark_node;
8279
8280 TREE_VALUE (tail) = output;
8281 }
8282
8283 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
8284 {
8285 tree input;
8286
8287 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
8288 input = TREE_VALUE (tail);
8289
8290 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
8291 oconstraints, &allows_mem, &allows_reg))
8292 {
8293 /* If the operand is going to end up in memory,
8294 mark it addressable. */
8295 if (!allows_reg && allows_mem)
8296 {
8297 /* Strip the nops as we allow this case. FIXME, this really
8298 should be rejected or made deprecated. */
8299 STRIP_NOPS (input);
8300 if (!c_mark_addressable (input))
8301 input = error_mark_node;
8302 }
8303 }
8304 else
8305 input = error_mark_node;
8306
8307 TREE_VALUE (tail) = input;
8308 }
8309
8310 /* ASMs with labels cannot have outputs. This should have been
8311 enforced by the parser. */
8312 gcc_assert (outputs == NULL || labels == NULL);
8313
8314 args = build_stmt (loc, ASM_EXPR, string, outputs, inputs, clobbers, labels);
8315
8316 /* asm statements without outputs, including simple ones, are treated
8317 as volatile. */
8318 ASM_INPUT_P (args) = simple;
8319 ASM_VOLATILE_P (args) = (noutputs == 0);
8320
8321 return args;
8322 }
8323 \f
8324 /* Generate a goto statement to LABEL. LOC is the location of the
8325 GOTO. */
8326
8327 tree
8328 c_finish_goto_label (location_t loc, tree label)
8329 {
8330 tree decl = lookup_label_for_goto (loc, label);
8331 if (!decl)
8332 return NULL_TREE;
8333 TREE_USED (decl) = 1;
8334 {
8335 tree t = build1 (GOTO_EXPR, void_type_node, decl);
8336 SET_EXPR_LOCATION (t, loc);
8337 return add_stmt (t);
8338 }
8339 }
8340
8341 /* Generate a computed goto statement to EXPR. LOC is the location of
8342 the GOTO. */
8343
8344 tree
8345 c_finish_goto_ptr (location_t loc, tree expr)
8346 {
8347 tree t;
8348 pedwarn (loc, OPT_pedantic, "ISO C forbids %<goto *expr;%>");
8349 expr = c_fully_fold (expr, false, NULL);
8350 expr = convert (ptr_type_node, expr);
8351 t = build1 (GOTO_EXPR, void_type_node, expr);
8352 SET_EXPR_LOCATION (t, loc);
8353 return add_stmt (t);
8354 }
8355
8356 /* Generate a C `return' statement. RETVAL is the expression for what
8357 to return, or a null pointer for `return;' with no value. LOC is
8358 the location of the return statement. If ORIGTYPE is not NULL_TREE, it
8359 is the original type of RETVAL. */
8360
8361 tree
8362 c_finish_return (location_t loc, tree retval, tree origtype)
8363 {
8364 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)), ret_stmt;
8365 bool no_warning = false;
8366 bool npc = false;
8367
8368 if (TREE_THIS_VOLATILE (current_function_decl))
8369 warning_at (loc, 0,
8370 "function declared %<noreturn%> has a %<return%> statement");
8371
8372 if (retval)
8373 {
8374 tree semantic_type = NULL_TREE;
8375 npc = null_pointer_constant_p (retval);
8376 if (TREE_CODE (retval) == EXCESS_PRECISION_EXPR)
8377 {
8378 semantic_type = TREE_TYPE (retval);
8379 retval = TREE_OPERAND (retval, 0);
8380 }
8381 retval = c_fully_fold (retval, false, NULL);
8382 if (semantic_type)
8383 retval = build1 (EXCESS_PRECISION_EXPR, semantic_type, retval);
8384 }
8385
8386 if (!retval)
8387 {
8388 current_function_returns_null = 1;
8389 if ((warn_return_type || flag_isoc99)
8390 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
8391 {
8392 pedwarn_c99 (loc, flag_isoc99 ? 0 : OPT_Wreturn_type,
8393 "%<return%> with no value, in "
8394 "function returning non-void");
8395 no_warning = true;
8396 }
8397 }
8398 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
8399 {
8400 current_function_returns_null = 1;
8401 if (TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
8402 pedwarn (loc, 0,
8403 "%<return%> with a value, in function returning void");
8404 else
8405 pedwarn (loc, OPT_pedantic, "ISO C forbids "
8406 "%<return%> with expression, in function returning void");
8407 }
8408 else
8409 {
8410 tree t = convert_for_assignment (loc, valtype, retval, origtype,
8411 ic_return,
8412 npc, NULL_TREE, NULL_TREE, 0);
8413 tree res = DECL_RESULT (current_function_decl);
8414 tree inner;
8415
8416 current_function_returns_value = 1;
8417 if (t == error_mark_node)
8418 return NULL_TREE;
8419
8420 inner = t = convert (TREE_TYPE (res), t);
8421
8422 /* Strip any conversions, additions, and subtractions, and see if
8423 we are returning the address of a local variable. Warn if so. */
8424 while (1)
8425 {
8426 switch (TREE_CODE (inner))
8427 {
8428 CASE_CONVERT:
8429 case NON_LVALUE_EXPR:
8430 case PLUS_EXPR:
8431 case POINTER_PLUS_EXPR:
8432 inner = TREE_OPERAND (inner, 0);
8433 continue;
8434
8435 case MINUS_EXPR:
8436 /* If the second operand of the MINUS_EXPR has a pointer
8437 type (or is converted from it), this may be valid, so
8438 don't give a warning. */
8439 {
8440 tree op1 = TREE_OPERAND (inner, 1);
8441
8442 while (!POINTER_TYPE_P (TREE_TYPE (op1))
8443 && (CONVERT_EXPR_P (op1)
8444 || TREE_CODE (op1) == NON_LVALUE_EXPR))
8445 op1 = TREE_OPERAND (op1, 0);
8446
8447 if (POINTER_TYPE_P (TREE_TYPE (op1)))
8448 break;
8449
8450 inner = TREE_OPERAND (inner, 0);
8451 continue;
8452 }
8453
8454 case ADDR_EXPR:
8455 inner = TREE_OPERAND (inner, 0);
8456
8457 while (REFERENCE_CLASS_P (inner)
8458 && TREE_CODE (inner) != INDIRECT_REF)
8459 inner = TREE_OPERAND (inner, 0);
8460
8461 if (DECL_P (inner)
8462 && !DECL_EXTERNAL (inner)
8463 && !TREE_STATIC (inner)
8464 && DECL_CONTEXT (inner) == current_function_decl)
8465 warning_at (loc,
8466 0, "function returns address of local variable");
8467 break;
8468
8469 default:
8470 break;
8471 }
8472
8473 break;
8474 }
8475
8476 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
8477 SET_EXPR_LOCATION (retval, loc);
8478
8479 if (warn_sequence_point)
8480 verify_sequence_points (retval);
8481 }
8482
8483 ret_stmt = build_stmt (loc, RETURN_EXPR, retval);
8484 TREE_NO_WARNING (ret_stmt) |= no_warning;
8485 return add_stmt (ret_stmt);
8486 }
8487 \f
8488 struct c_switch {
8489 /* The SWITCH_EXPR being built. */
8490 tree switch_expr;
8491
8492 /* The original type of the testing expression, i.e. before the
8493 default conversion is applied. */
8494 tree orig_type;
8495
8496 /* A splay-tree mapping the low element of a case range to the high
8497 element, or NULL_TREE if there is no high element. Used to
8498 determine whether or not a new case label duplicates an old case
8499 label. We need a tree, rather than simply a hash table, because
8500 of the GNU case range extension. */
8501 splay_tree cases;
8502
8503 /* The bindings at the point of the switch. This is used for
8504 warnings crossing decls when branching to a case label. */
8505 struct c_spot_bindings *bindings;
8506
8507 /* The next node on the stack. */
8508 struct c_switch *next;
8509 };
8510
8511 /* A stack of the currently active switch statements. The innermost
8512 switch statement is on the top of the stack. There is no need to
8513 mark the stack for garbage collection because it is only active
8514 during the processing of the body of a function, and we never
8515 collect at that point. */
8516
8517 struct c_switch *c_switch_stack;
8518
8519 /* Start a C switch statement, testing expression EXP. Return the new
8520 SWITCH_EXPR. SWITCH_LOC is the location of the `switch'.
8521 SWITCH_COND_LOC is the location of the switch's condition. */
8522
8523 tree
8524 c_start_case (location_t switch_loc,
8525 location_t switch_cond_loc,
8526 tree exp)
8527 {
8528 tree orig_type = error_mark_node;
8529 struct c_switch *cs;
8530
8531 if (exp != error_mark_node)
8532 {
8533 orig_type = TREE_TYPE (exp);
8534
8535 if (!INTEGRAL_TYPE_P (orig_type))
8536 {
8537 if (orig_type != error_mark_node)
8538 {
8539 error_at (switch_cond_loc, "switch quantity not an integer");
8540 orig_type = error_mark_node;
8541 }
8542 exp = integer_zero_node;
8543 }
8544 else
8545 {
8546 tree type = TYPE_MAIN_VARIANT (orig_type);
8547
8548 if (!in_system_header
8549 && (type == long_integer_type_node
8550 || type == long_unsigned_type_node))
8551 warning_at (switch_cond_loc,
8552 OPT_Wtraditional, "%<long%> switch expression not "
8553 "converted to %<int%> in ISO C");
8554
8555 exp = c_fully_fold (exp, false, NULL);
8556 exp = default_conversion (exp);
8557
8558 if (warn_sequence_point)
8559 verify_sequence_points (exp);
8560 }
8561 }
8562
8563 /* Add this new SWITCH_EXPR to the stack. */
8564 cs = XNEW (struct c_switch);
8565 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE);
8566 SET_EXPR_LOCATION (cs->switch_expr, switch_loc);
8567 cs->orig_type = orig_type;
8568 cs->cases = splay_tree_new (case_compare, NULL, NULL);
8569 cs->bindings = c_get_switch_bindings ();
8570 cs->next = c_switch_stack;
8571 c_switch_stack = cs;
8572
8573 return add_stmt (cs->switch_expr);
8574 }
8575
8576 /* Process a case label at location LOC. */
8577
8578 tree
8579 do_case (location_t loc, tree low_value, tree high_value)
8580 {
8581 tree label = NULL_TREE;
8582
8583 if (low_value && TREE_CODE (low_value) != INTEGER_CST)
8584 {
8585 low_value = c_fully_fold (low_value, false, NULL);
8586 if (TREE_CODE (low_value) == INTEGER_CST)
8587 pedwarn (input_location, OPT_pedantic,
8588 "case label is not an integer constant expression");
8589 }
8590
8591 if (high_value && TREE_CODE (high_value) != INTEGER_CST)
8592 {
8593 high_value = c_fully_fold (high_value, false, NULL);
8594 if (TREE_CODE (high_value) == INTEGER_CST)
8595 pedwarn (input_location, OPT_pedantic,
8596 "case label is not an integer constant expression");
8597 }
8598
8599 if (c_switch_stack == NULL)
8600 {
8601 if (low_value)
8602 error_at (loc, "case label not within a switch statement");
8603 else
8604 error_at (loc, "%<default%> label not within a switch statement");
8605 return NULL_TREE;
8606 }
8607
8608 if (c_check_switch_jump_warnings (c_switch_stack->bindings,
8609 EXPR_LOCATION (c_switch_stack->switch_expr),
8610 loc))
8611 return NULL_TREE;
8612
8613 label = c_add_case_label (loc, c_switch_stack->cases,
8614 SWITCH_COND (c_switch_stack->switch_expr),
8615 c_switch_stack->orig_type,
8616 low_value, high_value);
8617 if (label == error_mark_node)
8618 label = NULL_TREE;
8619 return label;
8620 }
8621
8622 /* Finish the switch statement. */
8623
8624 void
8625 c_finish_case (tree body)
8626 {
8627 struct c_switch *cs = c_switch_stack;
8628 location_t switch_location;
8629
8630 SWITCH_BODY (cs->switch_expr) = body;
8631
8632 /* Emit warnings as needed. */
8633 switch_location = EXPR_LOCATION (cs->switch_expr);
8634 c_do_switch_warnings (cs->cases, switch_location,
8635 TREE_TYPE (cs->switch_expr),
8636 SWITCH_COND (cs->switch_expr));
8637
8638 /* Pop the stack. */
8639 c_switch_stack = cs->next;
8640 splay_tree_delete (cs->cases);
8641 c_release_switch_bindings (cs->bindings);
8642 XDELETE (cs);
8643 }
8644 \f
8645 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
8646 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
8647 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
8648 statement, and was not surrounded with parenthesis. */
8649
8650 void
8651 c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
8652 tree else_block, bool nested_if)
8653 {
8654 tree stmt;
8655
8656 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
8657 if (warn_parentheses && nested_if && else_block == NULL)
8658 {
8659 tree inner_if = then_block;
8660
8661 /* We know from the grammar productions that there is an IF nested
8662 within THEN_BLOCK. Due to labels and c99 conditional declarations,
8663 it might not be exactly THEN_BLOCK, but should be the last
8664 non-container statement within. */
8665 while (1)
8666 switch (TREE_CODE (inner_if))
8667 {
8668 case COND_EXPR:
8669 goto found;
8670 case BIND_EXPR:
8671 inner_if = BIND_EXPR_BODY (inner_if);
8672 break;
8673 case STATEMENT_LIST:
8674 inner_if = expr_last (then_block);
8675 break;
8676 case TRY_FINALLY_EXPR:
8677 case TRY_CATCH_EXPR:
8678 inner_if = TREE_OPERAND (inner_if, 0);
8679 break;
8680 default:
8681 gcc_unreachable ();
8682 }
8683 found:
8684
8685 if (COND_EXPR_ELSE (inner_if))
8686 warning_at (if_locus, OPT_Wparentheses,
8687 "suggest explicit braces to avoid ambiguous %<else%>");
8688 }
8689
8690 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block);
8691 SET_EXPR_LOCATION (stmt, if_locus);
8692 add_stmt (stmt);
8693 }
8694
8695 /* Emit a general-purpose loop construct. START_LOCUS is the location of
8696 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
8697 is false for DO loops. INCR is the FOR increment expression. BODY is
8698 the statement controlled by the loop. BLAB is the break label. CLAB is
8699 the continue label. Everything is allowed to be NULL. */
8700
8701 void
8702 c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
8703 tree blab, tree clab, bool cond_is_first)
8704 {
8705 tree entry = NULL, exit = NULL, t;
8706
8707 /* If the condition is zero don't generate a loop construct. */
8708 if (cond && integer_zerop (cond))
8709 {
8710 if (cond_is_first)
8711 {
8712 t = build_and_jump (&blab);
8713 SET_EXPR_LOCATION (t, start_locus);
8714 add_stmt (t);
8715 }
8716 }
8717 else
8718 {
8719 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
8720
8721 /* If we have an exit condition, then we build an IF with gotos either
8722 out of the loop, or to the top of it. If there's no exit condition,
8723 then we just build a jump back to the top. */
8724 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
8725
8726 if (cond && !integer_nonzerop (cond))
8727 {
8728 /* Canonicalize the loop condition to the end. This means
8729 generating a branch to the loop condition. Reuse the
8730 continue label, if possible. */
8731 if (cond_is_first)
8732 {
8733 if (incr || !clab)
8734 {
8735 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
8736 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
8737 }
8738 else
8739 t = build1 (GOTO_EXPR, void_type_node, clab);
8740 SET_EXPR_LOCATION (t, start_locus);
8741 add_stmt (t);
8742 }
8743
8744 t = build_and_jump (&blab);
8745 if (cond_is_first)
8746 exit = fold_build3_loc (start_locus,
8747 COND_EXPR, void_type_node, cond, exit, t);
8748 else
8749 exit = fold_build3_loc (input_location,
8750 COND_EXPR, void_type_node, cond, exit, t);
8751 }
8752
8753 add_stmt (top);
8754 }
8755
8756 if (body)
8757 add_stmt (body);
8758 if (clab)
8759 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
8760 if (incr)
8761 add_stmt (incr);
8762 if (entry)
8763 add_stmt (entry);
8764 if (exit)
8765 add_stmt (exit);
8766 if (blab)
8767 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
8768 }
8769
8770 tree
8771 c_finish_bc_stmt (location_t loc, tree *label_p, bool is_break)
8772 {
8773 bool skip;
8774 tree label = *label_p;
8775
8776 /* In switch statements break is sometimes stylistically used after
8777 a return statement. This can lead to spurious warnings about
8778 control reaching the end of a non-void function when it is
8779 inlined. Note that we are calling block_may_fallthru with
8780 language specific tree nodes; this works because
8781 block_may_fallthru returns true when given something it does not
8782 understand. */
8783 skip = !block_may_fallthru (cur_stmt_list);
8784
8785 if (!label)
8786 {
8787 if (!skip)
8788 *label_p = label = create_artificial_label (loc);
8789 }
8790 else if (TREE_CODE (label) == LABEL_DECL)
8791 ;
8792 else switch (TREE_INT_CST_LOW (label))
8793 {
8794 case 0:
8795 if (is_break)
8796 error_at (loc, "break statement not within loop or switch");
8797 else
8798 error_at (loc, "continue statement not within a loop");
8799 return NULL_TREE;
8800
8801 case 1:
8802 gcc_assert (is_break);
8803 error_at (loc, "break statement used with OpenMP for loop");
8804 return NULL_TREE;
8805
8806 default:
8807 gcc_unreachable ();
8808 }
8809
8810 if (skip)
8811 return NULL_TREE;
8812
8813 if (!is_break)
8814 add_stmt (build_predict_expr (PRED_CONTINUE, NOT_TAKEN));
8815
8816 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
8817 }
8818
8819 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
8820
8821 static void
8822 emit_side_effect_warnings (location_t loc, tree expr)
8823 {
8824 if (expr == error_mark_node)
8825 ;
8826 else if (!TREE_SIDE_EFFECTS (expr))
8827 {
8828 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
8829 warning_at (loc, OPT_Wunused_value, "statement with no effect");
8830 }
8831 else
8832 warn_if_unused_value (expr, loc);
8833 }
8834
8835 /* Process an expression as if it were a complete statement. Emit
8836 diagnostics, but do not call ADD_STMT. LOC is the location of the
8837 statement. */
8838
8839 tree
8840 c_process_expr_stmt (location_t loc, tree expr)
8841 {
8842 if (!expr)
8843 return NULL_TREE;
8844
8845 expr = c_fully_fold (expr, false, NULL);
8846
8847 if (warn_sequence_point)
8848 verify_sequence_points (expr);
8849
8850 if (TREE_TYPE (expr) != error_mark_node
8851 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
8852 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
8853 error_at (loc, "expression statement has incomplete type");
8854
8855 /* If we're not processing a statement expression, warn about unused values.
8856 Warnings for statement expressions will be emitted later, once we figure
8857 out which is the result. */
8858 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
8859 && warn_unused_value)
8860 emit_side_effect_warnings (loc, expr);
8861
8862 if (DECL_P (expr) || handled_component_p (expr))
8863 mark_exp_read (expr);
8864
8865 /* If the expression is not of a type to which we cannot assign a line
8866 number, wrap the thing in a no-op NOP_EXPR. */
8867 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
8868 {
8869 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
8870 SET_EXPR_LOCATION (expr, loc);
8871 }
8872
8873 return expr;
8874 }
8875
8876 /* Emit an expression as a statement. LOC is the location of the
8877 expression. */
8878
8879 tree
8880 c_finish_expr_stmt (location_t loc, tree expr)
8881 {
8882 if (expr)
8883 return add_stmt (c_process_expr_stmt (loc, expr));
8884 else
8885 return NULL;
8886 }
8887
8888 /* Do the opposite and emit a statement as an expression. To begin,
8889 create a new binding level and return it. */
8890
8891 tree
8892 c_begin_stmt_expr (void)
8893 {
8894 tree ret;
8895
8896 /* We must force a BLOCK for this level so that, if it is not expanded
8897 later, there is a way to turn off the entire subtree of blocks that
8898 are contained in it. */
8899 keep_next_level ();
8900 ret = c_begin_compound_stmt (true);
8901
8902 c_bindings_start_stmt_expr (c_switch_stack == NULL
8903 ? NULL
8904 : c_switch_stack->bindings);
8905
8906 /* Mark the current statement list as belonging to a statement list. */
8907 STATEMENT_LIST_STMT_EXPR (ret) = 1;
8908
8909 return ret;
8910 }
8911
8912 /* LOC is the location of the compound statement to which this body
8913 belongs. */
8914
8915 tree
8916 c_finish_stmt_expr (location_t loc, tree body)
8917 {
8918 tree last, type, tmp, val;
8919 tree *last_p;
8920
8921 body = c_end_compound_stmt (loc, body, true);
8922
8923 c_bindings_end_stmt_expr (c_switch_stack == NULL
8924 ? NULL
8925 : c_switch_stack->bindings);
8926
8927 /* Locate the last statement in BODY. See c_end_compound_stmt
8928 about always returning a BIND_EXPR. */
8929 last_p = &BIND_EXPR_BODY (body);
8930 last = BIND_EXPR_BODY (body);
8931
8932 continue_searching:
8933 if (TREE_CODE (last) == STATEMENT_LIST)
8934 {
8935 tree_stmt_iterator i;
8936
8937 /* This can happen with degenerate cases like ({ }). No value. */
8938 if (!TREE_SIDE_EFFECTS (last))
8939 return body;
8940
8941 /* If we're supposed to generate side effects warnings, process
8942 all of the statements except the last. */
8943 if (warn_unused_value)
8944 {
8945 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
8946 {
8947 location_t tloc;
8948 tree t = tsi_stmt (i);
8949
8950 tloc = EXPR_HAS_LOCATION (t) ? EXPR_LOCATION (t) : loc;
8951 emit_side_effect_warnings (tloc, t);
8952 }
8953 }
8954 else
8955 i = tsi_last (last);
8956 last_p = tsi_stmt_ptr (i);
8957 last = *last_p;
8958 }
8959
8960 /* If the end of the list is exception related, then the list was split
8961 by a call to push_cleanup. Continue searching. */
8962 if (TREE_CODE (last) == TRY_FINALLY_EXPR
8963 || TREE_CODE (last) == TRY_CATCH_EXPR)
8964 {
8965 last_p = &TREE_OPERAND (last, 0);
8966 last = *last_p;
8967 goto continue_searching;
8968 }
8969
8970 if (last == error_mark_node)
8971 return last;
8972
8973 /* In the case that the BIND_EXPR is not necessary, return the
8974 expression out from inside it. */
8975 if (last == BIND_EXPR_BODY (body)
8976 && BIND_EXPR_VARS (body) == NULL)
8977 {
8978 /* Even if this looks constant, do not allow it in a constant
8979 expression. */
8980 last = c_wrap_maybe_const (last, true);
8981 /* Do not warn if the return value of a statement expression is
8982 unused. */
8983 TREE_NO_WARNING (last) = 1;
8984 return last;
8985 }
8986
8987 /* Extract the type of said expression. */
8988 type = TREE_TYPE (last);
8989
8990 /* If we're not returning a value at all, then the BIND_EXPR that
8991 we already have is a fine expression to return. */
8992 if (!type || VOID_TYPE_P (type))
8993 return body;
8994
8995 /* Now that we've located the expression containing the value, it seems
8996 silly to make voidify_wrapper_expr repeat the process. Create a
8997 temporary of the appropriate type and stick it in a TARGET_EXPR. */
8998 tmp = create_tmp_var_raw (type, NULL);
8999
9000 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
9001 tree_expr_nonnegative_p giving up immediately. */
9002 val = last;
9003 if (TREE_CODE (val) == NOP_EXPR
9004 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
9005 val = TREE_OPERAND (val, 0);
9006
9007 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
9008 SET_EXPR_LOCATION (*last_p, EXPR_LOCATION (last));
9009
9010 {
9011 tree t = build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
9012 SET_EXPR_LOCATION (t, loc);
9013 return t;
9014 }
9015 }
9016 \f
9017 /* Begin and end compound statements. This is as simple as pushing
9018 and popping new statement lists from the tree. */
9019
9020 tree
9021 c_begin_compound_stmt (bool do_scope)
9022 {
9023 tree stmt = push_stmt_list ();
9024 if (do_scope)
9025 push_scope ();
9026 return stmt;
9027 }
9028
9029 /* End a compound statement. STMT is the statement. LOC is the
9030 location of the compound statement-- this is usually the location
9031 of the opening brace. */
9032
9033 tree
9034 c_end_compound_stmt (location_t loc, tree stmt, bool do_scope)
9035 {
9036 tree block = NULL;
9037
9038 if (do_scope)
9039 {
9040 if (c_dialect_objc ())
9041 objc_clear_super_receiver ();
9042 block = pop_scope ();
9043 }
9044
9045 stmt = pop_stmt_list (stmt);
9046 stmt = c_build_bind_expr (loc, block, stmt);
9047
9048 /* If this compound statement is nested immediately inside a statement
9049 expression, then force a BIND_EXPR to be created. Otherwise we'll
9050 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
9051 STATEMENT_LISTs merge, and thus we can lose track of what statement
9052 was really last. */
9053 if (cur_stmt_list
9054 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
9055 && TREE_CODE (stmt) != BIND_EXPR)
9056 {
9057 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
9058 TREE_SIDE_EFFECTS (stmt) = 1;
9059 SET_EXPR_LOCATION (stmt, loc);
9060 }
9061
9062 return stmt;
9063 }
9064
9065 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
9066 when the current scope is exited. EH_ONLY is true when this is not
9067 meant to apply to normal control flow transfer. */
9068
9069 void
9070 push_cleanup (tree decl, tree cleanup, bool eh_only)
9071 {
9072 enum tree_code code;
9073 tree stmt, list;
9074 bool stmt_expr;
9075
9076 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
9077 stmt = build_stmt (DECL_SOURCE_LOCATION (decl), code, NULL, cleanup);
9078 add_stmt (stmt);
9079 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
9080 list = push_stmt_list ();
9081 TREE_OPERAND (stmt, 0) = list;
9082 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
9083 }
9084 \f
9085 /* Build a binary-operation expression without default conversions.
9086 CODE is the kind of expression to build.
9087 LOCATION is the operator's location.
9088 This function differs from `build' in several ways:
9089 the data type of the result is computed and recorded in it,
9090 warnings are generated if arg data types are invalid,
9091 special handling for addition and subtraction of pointers is known,
9092 and some optimization is done (operations on narrow ints
9093 are done in the narrower type when that gives the same result).
9094 Constant folding is also done before the result is returned.
9095
9096 Note that the operands will never have enumeral types, or function
9097 or array types, because either they will have the default conversions
9098 performed or they have both just been converted to some other type in which
9099 the arithmetic is to be done. */
9100
9101 tree
9102 build_binary_op (location_t location, enum tree_code code,
9103 tree orig_op0, tree orig_op1, int convert_p)
9104 {
9105 tree type0, type1, orig_type0, orig_type1;
9106 tree eptype;
9107 enum tree_code code0, code1;
9108 tree op0, op1;
9109 tree ret = error_mark_node;
9110 const char *invalid_op_diag;
9111 bool op0_int_operands, op1_int_operands;
9112 bool int_const, int_const_or_overflow, int_operands;
9113
9114 /* Expression code to give to the expression when it is built.
9115 Normally this is CODE, which is what the caller asked for,
9116 but in some special cases we change it. */
9117 enum tree_code resultcode = code;
9118
9119 /* Data type in which the computation is to be performed.
9120 In the simplest cases this is the common type of the arguments. */
9121 tree result_type = NULL;
9122
9123 /* When the computation is in excess precision, the type of the
9124 final EXCESS_PRECISION_EXPR. */
9125 tree semantic_result_type = NULL;
9126
9127 /* Nonzero means operands have already been type-converted
9128 in whatever way is necessary.
9129 Zero means they need to be converted to RESULT_TYPE. */
9130 int converted = 0;
9131
9132 /* Nonzero means create the expression with this type, rather than
9133 RESULT_TYPE. */
9134 tree build_type = 0;
9135
9136 /* Nonzero means after finally constructing the expression
9137 convert it to this type. */
9138 tree final_type = 0;
9139
9140 /* Nonzero if this is an operation like MIN or MAX which can
9141 safely be computed in short if both args are promoted shorts.
9142 Also implies COMMON.
9143 -1 indicates a bitwise operation; this makes a difference
9144 in the exact conditions for when it is safe to do the operation
9145 in a narrower mode. */
9146 int shorten = 0;
9147
9148 /* Nonzero if this is a comparison operation;
9149 if both args are promoted shorts, compare the original shorts.
9150 Also implies COMMON. */
9151 int short_compare = 0;
9152
9153 /* Nonzero if this is a right-shift operation, which can be computed on the
9154 original short and then promoted if the operand is a promoted short. */
9155 int short_shift = 0;
9156
9157 /* Nonzero means set RESULT_TYPE to the common type of the args. */
9158 int common = 0;
9159
9160 /* True means types are compatible as far as ObjC is concerned. */
9161 bool objc_ok;
9162
9163 /* True means this is an arithmetic operation that may need excess
9164 precision. */
9165 bool may_need_excess_precision;
9166
9167 if (location == UNKNOWN_LOCATION)
9168 location = input_location;
9169
9170 op0 = orig_op0;
9171 op1 = orig_op1;
9172
9173 op0_int_operands = EXPR_INT_CONST_OPERANDS (orig_op0);
9174 if (op0_int_operands)
9175 op0 = remove_c_maybe_const_expr (op0);
9176 op1_int_operands = EXPR_INT_CONST_OPERANDS (orig_op1);
9177 if (op1_int_operands)
9178 op1 = remove_c_maybe_const_expr (op1);
9179 int_operands = (op0_int_operands && op1_int_operands);
9180 if (int_operands)
9181 {
9182 int_const_or_overflow = (TREE_CODE (orig_op0) == INTEGER_CST
9183 && TREE_CODE (orig_op1) == INTEGER_CST);
9184 int_const = (int_const_or_overflow
9185 && !TREE_OVERFLOW (orig_op0)
9186 && !TREE_OVERFLOW (orig_op1));
9187 }
9188 else
9189 int_const = int_const_or_overflow = false;
9190
9191 if (convert_p)
9192 {
9193 op0 = default_conversion (op0);
9194 op1 = default_conversion (op1);
9195 }
9196
9197 orig_type0 = type0 = TREE_TYPE (op0);
9198 orig_type1 = type1 = TREE_TYPE (op1);
9199
9200 /* The expression codes of the data types of the arguments tell us
9201 whether the arguments are integers, floating, pointers, etc. */
9202 code0 = TREE_CODE (type0);
9203 code1 = TREE_CODE (type1);
9204
9205 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
9206 STRIP_TYPE_NOPS (op0);
9207 STRIP_TYPE_NOPS (op1);
9208
9209 /* If an error was already reported for one of the arguments,
9210 avoid reporting another error. */
9211
9212 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
9213 return error_mark_node;
9214
9215 if ((invalid_op_diag
9216 = targetm.invalid_binary_op (code, type0, type1)))
9217 {
9218 error_at (location, invalid_op_diag);
9219 return error_mark_node;
9220 }
9221
9222 switch (code)
9223 {
9224 case PLUS_EXPR:
9225 case MINUS_EXPR:
9226 case MULT_EXPR:
9227 case TRUNC_DIV_EXPR:
9228 case CEIL_DIV_EXPR:
9229 case FLOOR_DIV_EXPR:
9230 case ROUND_DIV_EXPR:
9231 case EXACT_DIV_EXPR:
9232 may_need_excess_precision = true;
9233 break;
9234 default:
9235 may_need_excess_precision = false;
9236 break;
9237 }
9238 if (TREE_CODE (op0) == EXCESS_PRECISION_EXPR)
9239 {
9240 op0 = TREE_OPERAND (op0, 0);
9241 type0 = TREE_TYPE (op0);
9242 }
9243 else if (may_need_excess_precision
9244 && (eptype = excess_precision_type (type0)) != NULL_TREE)
9245 {
9246 type0 = eptype;
9247 op0 = convert (eptype, op0);
9248 }
9249 if (TREE_CODE (op1) == EXCESS_PRECISION_EXPR)
9250 {
9251 op1 = TREE_OPERAND (op1, 0);
9252 type1 = TREE_TYPE (op1);
9253 }
9254 else if (may_need_excess_precision
9255 && (eptype = excess_precision_type (type1)) != NULL_TREE)
9256 {
9257 type1 = eptype;
9258 op1 = convert (eptype, op1);
9259 }
9260
9261 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE);
9262
9263 switch (code)
9264 {
9265 case PLUS_EXPR:
9266 /* Handle the pointer + int case. */
9267 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
9268 {
9269 ret = pointer_int_sum (location, PLUS_EXPR, op0, op1);
9270 goto return_build_binary_op;
9271 }
9272 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
9273 {
9274 ret = pointer_int_sum (location, PLUS_EXPR, op1, op0);
9275 goto return_build_binary_op;
9276 }
9277 else
9278 common = 1;
9279 break;
9280
9281 case MINUS_EXPR:
9282 /* Subtraction of two similar pointers.
9283 We must subtract them as integers, then divide by object size. */
9284 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
9285 && comp_target_types (location, type0, type1))
9286 {
9287 ret = pointer_diff (location, op0, op1);
9288 goto return_build_binary_op;
9289 }
9290 /* Handle pointer minus int. Just like pointer plus int. */
9291 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
9292 {
9293 ret = pointer_int_sum (location, MINUS_EXPR, op0, op1);
9294 goto return_build_binary_op;
9295 }
9296 else
9297 common = 1;
9298 break;
9299
9300 case MULT_EXPR:
9301 common = 1;
9302 break;
9303
9304 case TRUNC_DIV_EXPR:
9305 case CEIL_DIV_EXPR:
9306 case FLOOR_DIV_EXPR:
9307 case ROUND_DIV_EXPR:
9308 case EXACT_DIV_EXPR:
9309 warn_for_div_by_zero (location, op1);
9310
9311 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
9312 || code0 == FIXED_POINT_TYPE
9313 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
9314 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
9315 || code1 == FIXED_POINT_TYPE
9316 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
9317 {
9318 enum tree_code tcode0 = code0, tcode1 = code1;
9319
9320 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
9321 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
9322 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
9323 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
9324
9325 if (!((tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE)
9326 || (tcode0 == FIXED_POINT_TYPE && tcode1 == FIXED_POINT_TYPE)))
9327 resultcode = RDIV_EXPR;
9328 else
9329 /* Although it would be tempting to shorten always here, that
9330 loses on some targets, since the modulo instruction is
9331 undefined if the quotient can't be represented in the
9332 computation mode. We shorten only if unsigned or if
9333 dividing by something we know != -1. */
9334 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
9335 || (TREE_CODE (op1) == INTEGER_CST
9336 && !integer_all_onesp (op1)));
9337 common = 1;
9338 }
9339 break;
9340
9341 case BIT_AND_EXPR:
9342 case BIT_IOR_EXPR:
9343 case BIT_XOR_EXPR:
9344 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
9345 shorten = -1;
9346 /* Allow vector types which are not floating point types. */
9347 else if (code0 == VECTOR_TYPE
9348 && code1 == VECTOR_TYPE
9349 && !VECTOR_FLOAT_TYPE_P (type0)
9350 && !VECTOR_FLOAT_TYPE_P (type1))
9351 common = 1;
9352 break;
9353
9354 case TRUNC_MOD_EXPR:
9355 case FLOOR_MOD_EXPR:
9356 warn_for_div_by_zero (location, op1);
9357
9358 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
9359 && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE
9360 && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE)
9361 common = 1;
9362 else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
9363 {
9364 /* Although it would be tempting to shorten always here, that loses
9365 on some targets, since the modulo instruction is undefined if the
9366 quotient can't be represented in the computation mode. We shorten
9367 only if unsigned or if dividing by something we know != -1. */
9368 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
9369 || (TREE_CODE (op1) == INTEGER_CST
9370 && !integer_all_onesp (op1)));
9371 common = 1;
9372 }
9373 break;
9374
9375 case TRUTH_ANDIF_EXPR:
9376 case TRUTH_ORIF_EXPR:
9377 case TRUTH_AND_EXPR:
9378 case TRUTH_OR_EXPR:
9379 case TRUTH_XOR_EXPR:
9380 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
9381 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
9382 || code0 == FIXED_POINT_TYPE)
9383 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
9384 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
9385 || code1 == FIXED_POINT_TYPE))
9386 {
9387 /* Result of these operations is always an int,
9388 but that does not mean the operands should be
9389 converted to ints! */
9390 result_type = integer_type_node;
9391 op0 = c_common_truthvalue_conversion (location, op0);
9392 op1 = c_common_truthvalue_conversion (location, op1);
9393 converted = 1;
9394 }
9395 if (code == TRUTH_ANDIF_EXPR)
9396 {
9397 int_const_or_overflow = (int_operands
9398 && TREE_CODE (orig_op0) == INTEGER_CST
9399 && (op0 == truthvalue_false_node
9400 || TREE_CODE (orig_op1) == INTEGER_CST));
9401 int_const = (int_const_or_overflow
9402 && !TREE_OVERFLOW (orig_op0)
9403 && (op0 == truthvalue_false_node
9404 || !TREE_OVERFLOW (orig_op1)));
9405 }
9406 else if (code == TRUTH_ORIF_EXPR)
9407 {
9408 int_const_or_overflow = (int_operands
9409 && TREE_CODE (orig_op0) == INTEGER_CST
9410 && (op0 == truthvalue_true_node
9411 || TREE_CODE (orig_op1) == INTEGER_CST));
9412 int_const = (int_const_or_overflow
9413 && !TREE_OVERFLOW (orig_op0)
9414 && (op0 == truthvalue_true_node
9415 || !TREE_OVERFLOW (orig_op1)));
9416 }
9417 break;
9418
9419 /* Shift operations: result has same type as first operand;
9420 always convert second operand to int.
9421 Also set SHORT_SHIFT if shifting rightward. */
9422
9423 case RSHIFT_EXPR:
9424 if ((code0 == INTEGER_TYPE || code0 == FIXED_POINT_TYPE)
9425 && code1 == INTEGER_TYPE)
9426 {
9427 if (TREE_CODE (op1) == INTEGER_CST)
9428 {
9429 if (tree_int_cst_sgn (op1) < 0)
9430 {
9431 int_const = false;
9432 if (c_inhibit_evaluation_warnings == 0)
9433 warning (0, "right shift count is negative");
9434 }
9435 else
9436 {
9437 if (!integer_zerop (op1))
9438 short_shift = 1;
9439
9440 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
9441 {
9442 int_const = false;
9443 if (c_inhibit_evaluation_warnings == 0)
9444 warning (0, "right shift count >= width of type");
9445 }
9446 }
9447 }
9448
9449 /* Use the type of the value to be shifted. */
9450 result_type = type0;
9451 /* Convert the shift-count to an integer, regardless of size
9452 of value being shifted. */
9453 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
9454 op1 = convert (integer_type_node, op1);
9455 /* Avoid converting op1 to result_type later. */
9456 converted = 1;
9457 }
9458 break;
9459
9460 case LSHIFT_EXPR:
9461 if ((code0 == INTEGER_TYPE || code0 == FIXED_POINT_TYPE)
9462 && code1 == INTEGER_TYPE)
9463 {
9464 if (TREE_CODE (op1) == INTEGER_CST)
9465 {
9466 if (tree_int_cst_sgn (op1) < 0)
9467 {
9468 int_const = false;
9469 if (c_inhibit_evaluation_warnings == 0)
9470 warning (0, "left shift count is negative");
9471 }
9472
9473 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
9474 {
9475 int_const = false;
9476 if (c_inhibit_evaluation_warnings == 0)
9477 warning (0, "left shift count >= width of type");
9478 }
9479 }
9480
9481 /* Use the type of the value to be shifted. */
9482 result_type = type0;
9483 /* Convert the shift-count to an integer, regardless of size
9484 of value being shifted. */
9485 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
9486 op1 = convert (integer_type_node, op1);
9487 /* Avoid converting op1 to result_type later. */
9488 converted = 1;
9489 }
9490 break;
9491
9492 case EQ_EXPR:
9493 case NE_EXPR:
9494 if (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1))
9495 warning_at (location,
9496 OPT_Wfloat_equal,
9497 "comparing floating point with == or != is unsafe");
9498 /* Result of comparison is always int,
9499 but don't convert the args to int! */
9500 build_type = integer_type_node;
9501 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
9502 || code0 == FIXED_POINT_TYPE || code0 == COMPLEX_TYPE)
9503 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
9504 || code1 == FIXED_POINT_TYPE || code1 == COMPLEX_TYPE))
9505 short_compare = 1;
9506 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
9507 {
9508 tree tt0 = TREE_TYPE (type0);
9509 tree tt1 = TREE_TYPE (type1);
9510 addr_space_t as0 = TYPE_ADDR_SPACE (tt0);
9511 addr_space_t as1 = TYPE_ADDR_SPACE (tt1);
9512 addr_space_t as_common = ADDR_SPACE_GENERIC;
9513
9514 /* Anything compares with void *. void * compares with anything.
9515 Otherwise, the targets must be compatible
9516 and both must be object or both incomplete. */
9517 if (comp_target_types (location, type0, type1))
9518 result_type = common_pointer_type (type0, type1);
9519 else if (null_pointer_constant_p (orig_op0))
9520 result_type = type1;
9521 else if (null_pointer_constant_p (orig_op1))
9522 result_type = type0;
9523 else if (!addr_space_superset (as0, as1, &as_common))
9524 {
9525 error_at (location, "comparison of pointers to "
9526 "disjoint address spaces");
9527 return error_mark_node;
9528 }
9529 else if (VOID_TYPE_P (tt0))
9530 {
9531 if (pedantic && TREE_CODE (tt1) == FUNCTION_TYPE)
9532 pedwarn (location, OPT_pedantic, "ISO C forbids "
9533 "comparison of %<void *%> with function pointer");
9534 }
9535 else if (VOID_TYPE_P (tt1))
9536 {
9537 if (pedantic && TREE_CODE (tt0) == FUNCTION_TYPE)
9538 pedwarn (location, OPT_pedantic, "ISO C forbids "
9539 "comparison of %<void *%> with function pointer");
9540 }
9541 else
9542 /* Avoid warning about the volatile ObjC EH puts on decls. */
9543 if (!objc_ok)
9544 pedwarn (location, 0,
9545 "comparison of distinct pointer types lacks a cast");
9546
9547 if (result_type == NULL_TREE)
9548 {
9549 int qual = ENCODE_QUAL_ADDR_SPACE (as_common);
9550 result_type = build_pointer_type
9551 (build_qualified_type (void_type_node, qual));
9552 }
9553 }
9554 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
9555 {
9556 if (TREE_CODE (op0) == ADDR_EXPR
9557 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
9558 warning_at (location,
9559 OPT_Waddress, "the address of %qD will never be NULL",
9560 TREE_OPERAND (op0, 0));
9561 result_type = type0;
9562 }
9563 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
9564 {
9565 if (TREE_CODE (op1) == ADDR_EXPR
9566 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
9567 warning_at (location,
9568 OPT_Waddress, "the address of %qD will never be NULL",
9569 TREE_OPERAND (op1, 0));
9570 result_type = type1;
9571 }
9572 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
9573 {
9574 result_type = type0;
9575 pedwarn (location, 0, "comparison between pointer and integer");
9576 }
9577 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
9578 {
9579 result_type = type1;
9580 pedwarn (location, 0, "comparison between pointer and integer");
9581 }
9582 break;
9583
9584 case LE_EXPR:
9585 case GE_EXPR:
9586 case LT_EXPR:
9587 case GT_EXPR:
9588 build_type = integer_type_node;
9589 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
9590 || code0 == FIXED_POINT_TYPE)
9591 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
9592 || code1 == FIXED_POINT_TYPE))
9593 short_compare = 1;
9594 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
9595 {
9596 addr_space_t as0 = TYPE_ADDR_SPACE (TREE_TYPE (type0));
9597 addr_space_t as1 = TYPE_ADDR_SPACE (TREE_TYPE (type1));
9598 addr_space_t as_common;
9599
9600 if (comp_target_types (location, type0, type1))
9601 {
9602 result_type = common_pointer_type (type0, type1);
9603 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
9604 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
9605 pedwarn (location, 0,
9606 "comparison of complete and incomplete pointers");
9607 else if (TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
9608 pedwarn (location, OPT_pedantic, "ISO C forbids "
9609 "ordered comparisons of pointers to functions");
9610 }
9611 else if (!addr_space_superset (as0, as1, &as_common))
9612 {
9613 error_at (location, "comparison of pointers to "
9614 "disjoint address spaces");
9615 return error_mark_node;
9616 }
9617 else
9618 {
9619 int qual = ENCODE_QUAL_ADDR_SPACE (as_common);
9620 result_type = build_pointer_type
9621 (build_qualified_type (void_type_node, qual));
9622 pedwarn (location, 0,
9623 "comparison of distinct pointer types lacks a cast");
9624 }
9625 }
9626 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
9627 {
9628 result_type = type0;
9629 if (pedantic)
9630 pedwarn (location, OPT_pedantic,
9631 "ordered comparison of pointer with integer zero");
9632 else if (extra_warnings)
9633 warning_at (location, OPT_Wextra,
9634 "ordered comparison of pointer with integer zero");
9635 }
9636 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
9637 {
9638 result_type = type1;
9639 pedwarn (location, OPT_pedantic,
9640 "ordered comparison of pointer with integer zero");
9641 }
9642 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
9643 {
9644 result_type = type0;
9645 pedwarn (location, 0, "comparison between pointer and integer");
9646 }
9647 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
9648 {
9649 result_type = type1;
9650 pedwarn (location, 0, "comparison between pointer and integer");
9651 }
9652 break;
9653
9654 default:
9655 gcc_unreachable ();
9656 }
9657
9658 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
9659 return error_mark_node;
9660
9661 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
9662 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
9663 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
9664 TREE_TYPE (type1))))
9665 {
9666 binary_op_error (location, code, type0, type1);
9667 return error_mark_node;
9668 }
9669
9670 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
9671 || code0 == FIXED_POINT_TYPE || code0 == VECTOR_TYPE)
9672 &&
9673 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
9674 || code1 == FIXED_POINT_TYPE || code1 == VECTOR_TYPE))
9675 {
9676 bool first_complex = (code0 == COMPLEX_TYPE);
9677 bool second_complex = (code1 == COMPLEX_TYPE);
9678 int none_complex = (!first_complex && !second_complex);
9679
9680 if (shorten || common || short_compare)
9681 {
9682 result_type = c_common_type (type0, type1);
9683 if (result_type == error_mark_node)
9684 return error_mark_node;
9685 }
9686
9687 if (first_complex != second_complex
9688 && (code == PLUS_EXPR
9689 || code == MINUS_EXPR
9690 || code == MULT_EXPR
9691 || (code == TRUNC_DIV_EXPR && first_complex))
9692 && TREE_CODE (TREE_TYPE (result_type)) == REAL_TYPE
9693 && flag_signed_zeros)
9694 {
9695 /* An operation on mixed real/complex operands must be
9696 handled specially, but the language-independent code can
9697 more easily optimize the plain complex arithmetic if
9698 -fno-signed-zeros. */
9699 tree real_type = TREE_TYPE (result_type);
9700 tree real, imag;
9701 if (type0 != orig_type0 || type1 != orig_type1)
9702 {
9703 gcc_assert (may_need_excess_precision && common);
9704 semantic_result_type = c_common_type (orig_type0, orig_type1);
9705 }
9706 if (first_complex)
9707 {
9708 if (TREE_TYPE (op0) != result_type)
9709 op0 = convert_and_check (result_type, op0);
9710 if (TREE_TYPE (op1) != real_type)
9711 op1 = convert_and_check (real_type, op1);
9712 }
9713 else
9714 {
9715 if (TREE_TYPE (op0) != real_type)
9716 op0 = convert_and_check (real_type, op0);
9717 if (TREE_TYPE (op1) != result_type)
9718 op1 = convert_and_check (result_type, op1);
9719 }
9720 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
9721 return error_mark_node;
9722 if (first_complex)
9723 {
9724 op0 = c_save_expr (op0);
9725 real = build_unary_op (EXPR_LOCATION (orig_op0), REALPART_EXPR,
9726 op0, 1);
9727 imag = build_unary_op (EXPR_LOCATION (orig_op0), IMAGPART_EXPR,
9728 op0, 1);
9729 switch (code)
9730 {
9731 case MULT_EXPR:
9732 case TRUNC_DIV_EXPR:
9733 imag = build2 (resultcode, real_type, imag, op1);
9734 /* Fall through. */
9735 case PLUS_EXPR:
9736 case MINUS_EXPR:
9737 real = build2 (resultcode, real_type, real, op1);
9738 break;
9739 default:
9740 gcc_unreachable();
9741 }
9742 }
9743 else
9744 {
9745 op1 = c_save_expr (op1);
9746 real = build_unary_op (EXPR_LOCATION (orig_op1), REALPART_EXPR,
9747 op1, 1);
9748 imag = build_unary_op (EXPR_LOCATION (orig_op1), IMAGPART_EXPR,
9749 op1, 1);
9750 switch (code)
9751 {
9752 case MULT_EXPR:
9753 imag = build2 (resultcode, real_type, op0, imag);
9754 /* Fall through. */
9755 case PLUS_EXPR:
9756 real = build2 (resultcode, real_type, op0, real);
9757 break;
9758 case MINUS_EXPR:
9759 real = build2 (resultcode, real_type, op0, real);
9760 imag = build1 (NEGATE_EXPR, real_type, imag);
9761 break;
9762 default:
9763 gcc_unreachable();
9764 }
9765 }
9766 ret = build2 (COMPLEX_EXPR, result_type, real, imag);
9767 goto return_build_binary_op;
9768 }
9769
9770 /* For certain operations (which identify themselves by shorten != 0)
9771 if both args were extended from the same smaller type,
9772 do the arithmetic in that type and then extend.
9773
9774 shorten !=0 and !=1 indicates a bitwise operation.
9775 For them, this optimization is safe only if
9776 both args are zero-extended or both are sign-extended.
9777 Otherwise, we might change the result.
9778 Eg, (short)-1 | (unsigned short)-1 is (int)-1
9779 but calculated in (unsigned short) it would be (unsigned short)-1. */
9780
9781 if (shorten && none_complex)
9782 {
9783 final_type = result_type;
9784 result_type = shorten_binary_op (result_type, op0, op1,
9785 shorten == -1);
9786 }
9787
9788 /* Shifts can be shortened if shifting right. */
9789
9790 if (short_shift)
9791 {
9792 int unsigned_arg;
9793 tree arg0 = get_narrower (op0, &unsigned_arg);
9794
9795 final_type = result_type;
9796
9797 if (arg0 == op0 && final_type == TREE_TYPE (op0))
9798 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
9799
9800 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
9801 && tree_int_cst_sgn (op1) > 0
9802 /* We can shorten only if the shift count is less than the
9803 number of bits in the smaller type size. */
9804 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
9805 /* We cannot drop an unsigned shift after sign-extension. */
9806 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
9807 {
9808 /* Do an unsigned shift if the operand was zero-extended. */
9809 result_type
9810 = c_common_signed_or_unsigned_type (unsigned_arg,
9811 TREE_TYPE (arg0));
9812 /* Convert value-to-be-shifted to that type. */
9813 if (TREE_TYPE (op0) != result_type)
9814 op0 = convert (result_type, op0);
9815 converted = 1;
9816 }
9817 }
9818
9819 /* Comparison operations are shortened too but differently.
9820 They identify themselves by setting short_compare = 1. */
9821
9822 if (short_compare)
9823 {
9824 /* Don't write &op0, etc., because that would prevent op0
9825 from being kept in a register.
9826 Instead, make copies of the our local variables and
9827 pass the copies by reference, then copy them back afterward. */
9828 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
9829 enum tree_code xresultcode = resultcode;
9830 tree val
9831 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
9832
9833 if (val != 0)
9834 {
9835 ret = val;
9836 goto return_build_binary_op;
9837 }
9838
9839 op0 = xop0, op1 = xop1;
9840 converted = 1;
9841 resultcode = xresultcode;
9842
9843 if (c_inhibit_evaluation_warnings == 0)
9844 {
9845 bool op0_maybe_const = true;
9846 bool op1_maybe_const = true;
9847 tree orig_op0_folded, orig_op1_folded;
9848
9849 if (in_late_binary_op)
9850 {
9851 orig_op0_folded = orig_op0;
9852 orig_op1_folded = orig_op1;
9853 }
9854 else
9855 {
9856 /* Fold for the sake of possible warnings, as in
9857 build_conditional_expr. This requires the
9858 "original" values to be folded, not just op0 and
9859 op1. */
9860 c_inhibit_evaluation_warnings++;
9861 op0 = c_fully_fold (op0, require_constant_value,
9862 &op0_maybe_const);
9863 op1 = c_fully_fold (op1, require_constant_value,
9864 &op1_maybe_const);
9865 c_inhibit_evaluation_warnings--;
9866 orig_op0_folded = c_fully_fold (orig_op0,
9867 require_constant_value,
9868 NULL);
9869 orig_op1_folded = c_fully_fold (orig_op1,
9870 require_constant_value,
9871 NULL);
9872 }
9873
9874 if (warn_sign_compare)
9875 warn_for_sign_compare (location, orig_op0_folded,
9876 orig_op1_folded, op0, op1,
9877 result_type, resultcode);
9878 if (!in_late_binary_op)
9879 {
9880 if (!op0_maybe_const || TREE_CODE (op0) != INTEGER_CST)
9881 op0 = c_wrap_maybe_const (op0, !op0_maybe_const);
9882 if (!op1_maybe_const || TREE_CODE (op1) != INTEGER_CST)
9883 op1 = c_wrap_maybe_const (op1, !op1_maybe_const);
9884 }
9885 }
9886 }
9887 }
9888
9889 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
9890 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
9891 Then the expression will be built.
9892 It will be given type FINAL_TYPE if that is nonzero;
9893 otherwise, it will be given type RESULT_TYPE. */
9894
9895 if (!result_type)
9896 {
9897 binary_op_error (location, code, TREE_TYPE (op0), TREE_TYPE (op1));
9898 return error_mark_node;
9899 }
9900
9901 if (build_type == NULL_TREE)
9902 {
9903 build_type = result_type;
9904 if (type0 != orig_type0 || type1 != orig_type1)
9905 {
9906 gcc_assert (may_need_excess_precision && common);
9907 semantic_result_type = c_common_type (orig_type0, orig_type1);
9908 }
9909 }
9910
9911 if (!converted)
9912 {
9913 op0 = ep_convert_and_check (result_type, op0, semantic_result_type);
9914 op1 = ep_convert_and_check (result_type, op1, semantic_result_type);
9915
9916 /* This can happen if one operand has a vector type, and the other
9917 has a different type. */
9918 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
9919 return error_mark_node;
9920 }
9921
9922 /* Treat expressions in initializers specially as they can't trap. */
9923 if (int_const_or_overflow)
9924 ret = (require_constant_value
9925 ? fold_build2_initializer_loc (location, resultcode, build_type,
9926 op0, op1)
9927 : fold_build2_loc (location, resultcode, build_type, op0, op1));
9928 else
9929 ret = build2 (resultcode, build_type, op0, op1);
9930 if (final_type != 0)
9931 ret = convert (final_type, ret);
9932
9933 return_build_binary_op:
9934 gcc_assert (ret != error_mark_node);
9935 if (TREE_CODE (ret) == INTEGER_CST && !TREE_OVERFLOW (ret) && !int_const)
9936 ret = (int_operands
9937 ? note_integer_operands (ret)
9938 : build1 (NOP_EXPR, TREE_TYPE (ret), ret));
9939 else if (TREE_CODE (ret) != INTEGER_CST && int_operands
9940 && !in_late_binary_op)
9941 ret = note_integer_operands (ret);
9942 if (semantic_result_type)
9943 ret = build1 (EXCESS_PRECISION_EXPR, semantic_result_type, ret);
9944 protected_set_expr_location (ret, location);
9945 return ret;
9946 }
9947
9948
9949 /* Convert EXPR to be a truth-value, validating its type for this
9950 purpose. LOCATION is the source location for the expression. */
9951
9952 tree
9953 c_objc_common_truthvalue_conversion (location_t location, tree expr)
9954 {
9955 bool int_const, int_operands;
9956
9957 switch (TREE_CODE (TREE_TYPE (expr)))
9958 {
9959 case ARRAY_TYPE:
9960 error_at (location, "used array that cannot be converted to pointer where scalar is required");
9961 return error_mark_node;
9962
9963 case RECORD_TYPE:
9964 error_at (location, "used struct type value where scalar is required");
9965 return error_mark_node;
9966
9967 case UNION_TYPE:
9968 error_at (location, "used union type value where scalar is required");
9969 return error_mark_node;
9970
9971 case FUNCTION_TYPE:
9972 gcc_unreachable ();
9973
9974 default:
9975 break;
9976 }
9977
9978 int_const = (TREE_CODE (expr) == INTEGER_CST && !TREE_OVERFLOW (expr));
9979 int_operands = EXPR_INT_CONST_OPERANDS (expr);
9980 if (int_operands)
9981 expr = remove_c_maybe_const_expr (expr);
9982
9983 /* ??? Should we also give an error for void and vectors rather than
9984 leaving those to give errors later? */
9985 expr = c_common_truthvalue_conversion (location, expr);
9986
9987 if (TREE_CODE (expr) == INTEGER_CST && int_operands && !int_const)
9988 {
9989 if (TREE_OVERFLOW (expr))
9990 return expr;
9991 else
9992 return note_integer_operands (expr);
9993 }
9994 if (TREE_CODE (expr) == INTEGER_CST && !int_const)
9995 return build1 (NOP_EXPR, TREE_TYPE (expr), expr);
9996 return expr;
9997 }
9998 \f
9999
10000 /* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as
10001 required. */
10002
10003 tree
10004 c_expr_to_decl (tree expr, bool *tc ATTRIBUTE_UNUSED, bool *se)
10005 {
10006 if (TREE_CODE (expr) == COMPOUND_LITERAL_EXPR)
10007 {
10008 tree decl = COMPOUND_LITERAL_EXPR_DECL (expr);
10009 /* Executing a compound literal inside a function reinitializes
10010 it. */
10011 if (!TREE_STATIC (decl))
10012 *se = true;
10013 return decl;
10014 }
10015 else
10016 return expr;
10017 }
10018 \f
10019 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
10020
10021 tree
10022 c_begin_omp_parallel (void)
10023 {
10024 tree block;
10025
10026 keep_next_level ();
10027 block = c_begin_compound_stmt (true);
10028
10029 return block;
10030 }
10031
10032 /* Generate OMP_PARALLEL, with CLAUSES and BLOCK as its compound
10033 statement. LOC is the location of the OMP_PARALLEL. */
10034
10035 tree
10036 c_finish_omp_parallel (location_t loc, tree clauses, tree block)
10037 {
10038 tree stmt;
10039
10040 block = c_end_compound_stmt (loc, block, true);
10041
10042 stmt = make_node (OMP_PARALLEL);
10043 TREE_TYPE (stmt) = void_type_node;
10044 OMP_PARALLEL_CLAUSES (stmt) = clauses;
10045 OMP_PARALLEL_BODY (stmt) = block;
10046 SET_EXPR_LOCATION (stmt, loc);
10047
10048 return add_stmt (stmt);
10049 }
10050
10051 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
10052
10053 tree
10054 c_begin_omp_task (void)
10055 {
10056 tree block;
10057
10058 keep_next_level ();
10059 block = c_begin_compound_stmt (true);
10060
10061 return block;
10062 }
10063
10064 /* Generate OMP_TASK, with CLAUSES and BLOCK as its compound
10065 statement. LOC is the location of the #pragma. */
10066
10067 tree
10068 c_finish_omp_task (location_t loc, tree clauses, tree block)
10069 {
10070 tree stmt;
10071
10072 block = c_end_compound_stmt (loc, block, true);
10073
10074 stmt = make_node (OMP_TASK);
10075 TREE_TYPE (stmt) = void_type_node;
10076 OMP_TASK_CLAUSES (stmt) = clauses;
10077 OMP_TASK_BODY (stmt) = block;
10078 SET_EXPR_LOCATION (stmt, loc);
10079
10080 return add_stmt (stmt);
10081 }
10082
10083 /* For all elements of CLAUSES, validate them vs OpenMP constraints.
10084 Remove any elements from the list that are invalid. */
10085
10086 tree
10087 c_finish_omp_clauses (tree clauses)
10088 {
10089 bitmap_head generic_head, firstprivate_head, lastprivate_head;
10090 tree c, t, *pc = &clauses;
10091 const char *name;
10092
10093 bitmap_obstack_initialize (NULL);
10094 bitmap_initialize (&generic_head, &bitmap_default_obstack);
10095 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack);
10096 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack);
10097
10098 for (pc = &clauses, c = clauses; c ; c = *pc)
10099 {
10100 bool remove = false;
10101 bool need_complete = false;
10102 bool need_implicitly_determined = false;
10103
10104 switch (OMP_CLAUSE_CODE (c))
10105 {
10106 case OMP_CLAUSE_SHARED:
10107 name = "shared";
10108 need_implicitly_determined = true;
10109 goto check_dup_generic;
10110
10111 case OMP_CLAUSE_PRIVATE:
10112 name = "private";
10113 need_complete = true;
10114 need_implicitly_determined = true;
10115 goto check_dup_generic;
10116
10117 case OMP_CLAUSE_REDUCTION:
10118 name = "reduction";
10119 need_implicitly_determined = true;
10120 t = OMP_CLAUSE_DECL (c);
10121 if (AGGREGATE_TYPE_P (TREE_TYPE (t))
10122 || POINTER_TYPE_P (TREE_TYPE (t)))
10123 {
10124 error_at (OMP_CLAUSE_LOCATION (c),
10125 "%qE has invalid type for %<reduction%>", t);
10126 remove = true;
10127 }
10128 else if (FLOAT_TYPE_P (TREE_TYPE (t)))
10129 {
10130 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c);
10131 const char *r_name = NULL;
10132
10133 switch (r_code)
10134 {
10135 case PLUS_EXPR:
10136 case MULT_EXPR:
10137 case MINUS_EXPR:
10138 break;
10139 case BIT_AND_EXPR:
10140 r_name = "&";
10141 break;
10142 case BIT_XOR_EXPR:
10143 r_name = "^";
10144 break;
10145 case BIT_IOR_EXPR:
10146 r_name = "|";
10147 break;
10148 case TRUTH_ANDIF_EXPR:
10149 r_name = "&&";
10150 break;
10151 case TRUTH_ORIF_EXPR:
10152 r_name = "||";
10153 break;
10154 default:
10155 gcc_unreachable ();
10156 }
10157 if (r_name)
10158 {
10159 error_at (OMP_CLAUSE_LOCATION (c),
10160 "%qE has invalid type for %<reduction(%s)%>",
10161 t, r_name);
10162 remove = true;
10163 }
10164 }
10165 goto check_dup_generic;
10166
10167 case OMP_CLAUSE_COPYPRIVATE:
10168 name = "copyprivate";
10169 goto check_dup_generic;
10170
10171 case OMP_CLAUSE_COPYIN:
10172 name = "copyin";
10173 t = OMP_CLAUSE_DECL (c);
10174 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t))
10175 {
10176 error_at (OMP_CLAUSE_LOCATION (c),
10177 "%qE must be %<threadprivate%> for %<copyin%>", t);
10178 remove = true;
10179 }
10180 goto check_dup_generic;
10181
10182 check_dup_generic:
10183 t = OMP_CLAUSE_DECL (c);
10184 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
10185 {
10186 error_at (OMP_CLAUSE_LOCATION (c),
10187 "%qE is not a variable in clause %qs", t, name);
10188 remove = true;
10189 }
10190 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
10191 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))
10192 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
10193 {
10194 error_at (OMP_CLAUSE_LOCATION (c),
10195 "%qE appears more than once in data clauses", t);
10196 remove = true;
10197 }
10198 else
10199 bitmap_set_bit (&generic_head, DECL_UID (t));
10200 break;
10201
10202 case OMP_CLAUSE_FIRSTPRIVATE:
10203 name = "firstprivate";
10204 t = OMP_CLAUSE_DECL (c);
10205 need_complete = true;
10206 need_implicitly_determined = true;
10207 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
10208 {
10209 error_at (OMP_CLAUSE_LOCATION (c),
10210 "%qE is not a variable in clause %<firstprivate%>", t);
10211 remove = true;
10212 }
10213 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
10214 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)))
10215 {
10216 error_at (OMP_CLAUSE_LOCATION (c),
10217 "%qE appears more than once in data clauses", t);
10218 remove = true;
10219 }
10220 else
10221 bitmap_set_bit (&firstprivate_head, DECL_UID (t));
10222 break;
10223
10224 case OMP_CLAUSE_LASTPRIVATE:
10225 name = "lastprivate";
10226 t = OMP_CLAUSE_DECL (c);
10227 need_complete = true;
10228 need_implicitly_determined = true;
10229 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
10230 {
10231 error_at (OMP_CLAUSE_LOCATION (c),
10232 "%qE is not a variable in clause %<lastprivate%>", t);
10233 remove = true;
10234 }
10235 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
10236 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
10237 {
10238 error_at (OMP_CLAUSE_LOCATION (c),
10239 "%qE appears more than once in data clauses", t);
10240 remove = true;
10241 }
10242 else
10243 bitmap_set_bit (&lastprivate_head, DECL_UID (t));
10244 break;
10245
10246 case OMP_CLAUSE_IF:
10247 case OMP_CLAUSE_NUM_THREADS:
10248 case OMP_CLAUSE_SCHEDULE:
10249 case OMP_CLAUSE_NOWAIT:
10250 case OMP_CLAUSE_ORDERED:
10251 case OMP_CLAUSE_DEFAULT:
10252 case OMP_CLAUSE_UNTIED:
10253 case OMP_CLAUSE_COLLAPSE:
10254 pc = &OMP_CLAUSE_CHAIN (c);
10255 continue;
10256
10257 default:
10258 gcc_unreachable ();
10259 }
10260
10261 if (!remove)
10262 {
10263 t = OMP_CLAUSE_DECL (c);
10264
10265 if (need_complete)
10266 {
10267 t = require_complete_type (t);
10268 if (t == error_mark_node)
10269 remove = true;
10270 }
10271
10272 if (need_implicitly_determined)
10273 {
10274 const char *share_name = NULL;
10275
10276 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t))
10277 share_name = "threadprivate";
10278 else switch (c_omp_predetermined_sharing (t))
10279 {
10280 case OMP_CLAUSE_DEFAULT_UNSPECIFIED:
10281 break;
10282 case OMP_CLAUSE_DEFAULT_SHARED:
10283 share_name = "shared";
10284 break;
10285 case OMP_CLAUSE_DEFAULT_PRIVATE:
10286 share_name = "private";
10287 break;
10288 default:
10289 gcc_unreachable ();
10290 }
10291 if (share_name)
10292 {
10293 error_at (OMP_CLAUSE_LOCATION (c),
10294 "%qE is predetermined %qs for %qs",
10295 t, share_name, name);
10296 remove = true;
10297 }
10298 }
10299 }
10300
10301 if (remove)
10302 *pc = OMP_CLAUSE_CHAIN (c);
10303 else
10304 pc = &OMP_CLAUSE_CHAIN (c);
10305 }
10306
10307 bitmap_obstack_release (NULL);
10308 return clauses;
10309 }
10310
10311 /* Make a variant type in the proper way for C/C++, propagating qualifiers
10312 down to the element type of an array. */
10313
10314 tree
10315 c_build_qualified_type (tree type, int type_quals)
10316 {
10317 if (type == error_mark_node)
10318 return type;
10319
10320 if (TREE_CODE (type) == ARRAY_TYPE)
10321 {
10322 tree t;
10323 tree element_type = c_build_qualified_type (TREE_TYPE (type),
10324 type_quals);
10325
10326 /* See if we already have an identically qualified type. */
10327 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
10328 {
10329 if (TYPE_QUALS (strip_array_types (t)) == type_quals
10330 && TYPE_NAME (t) == TYPE_NAME (type)
10331 && TYPE_CONTEXT (t) == TYPE_CONTEXT (type)
10332 && attribute_list_equal (TYPE_ATTRIBUTES (t),
10333 TYPE_ATTRIBUTES (type)))
10334 break;
10335 }
10336 if (!t)
10337 {
10338 tree domain = TYPE_DOMAIN (type);
10339
10340 t = build_variant_type_copy (type);
10341 TREE_TYPE (t) = element_type;
10342
10343 if (TYPE_STRUCTURAL_EQUALITY_P (element_type)
10344 || (domain && TYPE_STRUCTURAL_EQUALITY_P (domain)))
10345 SET_TYPE_STRUCTURAL_EQUALITY (t);
10346 else if (TYPE_CANONICAL (element_type) != element_type
10347 || (domain && TYPE_CANONICAL (domain) != domain))
10348 {
10349 tree unqualified_canon
10350 = build_array_type (TYPE_CANONICAL (element_type),
10351 domain? TYPE_CANONICAL (domain)
10352 : NULL_TREE);
10353 TYPE_CANONICAL (t)
10354 = c_build_qualified_type (unqualified_canon, type_quals);
10355 }
10356 else
10357 TYPE_CANONICAL (t) = t;
10358 }
10359 return t;
10360 }
10361
10362 /* A restrict-qualified pointer type must be a pointer to object or
10363 incomplete type. Note that the use of POINTER_TYPE_P also allows
10364 REFERENCE_TYPEs, which is appropriate for C++. */
10365 if ((type_quals & TYPE_QUAL_RESTRICT)
10366 && (!POINTER_TYPE_P (type)
10367 || !C_TYPE_OBJECT_OR_INCOMPLETE_P (TREE_TYPE (type))))
10368 {
10369 error ("invalid use of %<restrict%>");
10370 type_quals &= ~TYPE_QUAL_RESTRICT;
10371 }
10372
10373 return build_qualified_type (type, type_quals);
10374 }
10375
10376 /* Build a VA_ARG_EXPR for the C parser. */
10377
10378 tree
10379 c_build_va_arg (location_t loc, tree expr, tree type)
10380 {
10381 if (warn_cxx_compat && TREE_CODE (type) == ENUMERAL_TYPE)
10382 warning_at (loc, OPT_Wc___compat,
10383 "C++ requires promoted type, not enum type, in %<va_arg%>");
10384 return build_va_arg (loc, expr, type);
10385 }