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* common.opt (flag_force_mem): Remove.
[official-gcc.git] / gcc / c-typeck.c
blob08f7d4a3a7965f4637c69571f6653fd5453cf873
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
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 2, 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 COPYING. If not, write to the Free
20 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
21 02110-1301, USA. */
22
23
24 /* This file is part of the C front end.
25 It contains routines to build C expressions given their operands,
26 including computing the types of the result, C-specific error checks,
27 and some optimization. */
28
29 #include "config.h"
30 #include "system.h"
31 #include "coretypes.h"
32 #include "tm.h"
33 #include "rtl.h"
34 #include "tree.h"
35 #include "langhooks.h"
36 #include "c-tree.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 "tree-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_argpass_nonproto,
54 ic_assign,
55 ic_init,
56 ic_return
57 };
58
59 /* The level of nesting inside "__alignof__". */
60 int in_alignof;
61
62 /* The level of nesting inside "sizeof". */
63 int in_sizeof;
64
65 /* The level of nesting inside "typeof". */
66 int in_typeof;
67
68 struct c_label_context_se *label_context_stack_se;
69 struct c_label_context_vm *label_context_stack_vm;
70
71 /* Nonzero if we've already printed a "missing braces around initializer"
72 message within this initializer. */
73 static int missing_braces_mentioned;
74
75 static int require_constant_value;
76 static int require_constant_elements;
77
78 static bool null_pointer_constant_p (tree);
79 static tree qualify_type (tree, tree);
80 static int tagged_types_tu_compatible_p (tree, tree);
81 static int comp_target_types (tree, tree);
82 static int function_types_compatible_p (tree, tree);
83 static int type_lists_compatible_p (tree, tree);
84 static tree decl_constant_value_for_broken_optimization (tree);
85 static tree lookup_field (tree, tree);
86 static tree convert_arguments (tree, tree, tree, tree);
87 static tree pointer_diff (tree, tree);
88 static tree convert_for_assignment (tree, tree, enum impl_conv, tree, tree,
89 int);
90 static tree valid_compound_expr_initializer (tree, tree);
91 static void push_string (const char *);
92 static void push_member_name (tree);
93 static int spelling_length (void);
94 static char *print_spelling (char *);
95 static void warning_init (const char *);
96 static tree digest_init (tree, tree, bool, int);
97 static void output_init_element (tree, bool, tree, tree, int);
98 static void output_pending_init_elements (int);
99 static int set_designator (int);
100 static void push_range_stack (tree);
101 static void add_pending_init (tree, tree);
102 static void set_nonincremental_init (void);
103 static void set_nonincremental_init_from_string (tree);
104 static tree find_init_member (tree);
105 static void readonly_error (tree, enum lvalue_use);
106 static int lvalue_or_else (tree, enum lvalue_use);
107 static int lvalue_p (tree);
108 static void record_maybe_used_decl (tree);
109 static int comptypes_internal (tree, tree);
110 \f
111 /* Return true if EXP is a null pointer constant, false otherwise. */
112
113 static bool
114 null_pointer_constant_p (tree expr)
115 {
116 /* This should really operate on c_expr structures, but they aren't
117 yet available everywhere required. */
118 tree type = TREE_TYPE (expr);
119 return (TREE_CODE (expr) == INTEGER_CST
120 && !TREE_CONSTANT_OVERFLOW (expr)
121 && integer_zerop (expr)
122 && (INTEGRAL_TYPE_P (type)
123 || (TREE_CODE (type) == POINTER_TYPE
124 && VOID_TYPE_P (TREE_TYPE (type))
125 && TYPE_QUALS (TREE_TYPE (type)) == TYPE_UNQUALIFIED)));
126 }
127 \f/* This is a cache to hold if two types are compatible or not. */
128
129 struct tagged_tu_seen_cache {
130 const struct tagged_tu_seen_cache * next;
131 tree t1;
132 tree t2;
133 /* The return value of tagged_types_tu_compatible_p if we had seen
134 these two types already. */
135 int val;
136 };
137
138 static const struct tagged_tu_seen_cache * tagged_tu_seen_base;
139 static void free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *);
140
141 /* Do `exp = require_complete_type (exp);' to make sure exp
142 does not have an incomplete type. (That includes void types.) */
143
144 tree
145 require_complete_type (tree value)
146 {
147 tree type = TREE_TYPE (value);
148
149 if (value == error_mark_node || type == error_mark_node)
150 return error_mark_node;
151
152 /* First, detect a valid value with a complete type. */
153 if (COMPLETE_TYPE_P (type))
154 return value;
155
156 c_incomplete_type_error (value, type);
157 return error_mark_node;
158 }
159
160 /* Print an error message for invalid use of an incomplete type.
161 VALUE is the expression that was used (or 0 if that isn't known)
162 and TYPE is the type that was invalid. */
163
164 void
165 c_incomplete_type_error (tree value, tree type)
166 {
167 const char *type_code_string;
168
169 /* Avoid duplicate error message. */
170 if (TREE_CODE (type) == ERROR_MARK)
171 return;
172
173 if (value != 0 && (TREE_CODE (value) == VAR_DECL
174 || TREE_CODE (value) == PARM_DECL))
175 error ("%qD has an incomplete type", value);
176 else
177 {
178 retry:
179 /* We must print an error message. Be clever about what it says. */
180
181 switch (TREE_CODE (type))
182 {
183 case RECORD_TYPE:
184 type_code_string = "struct";
185 break;
186
187 case UNION_TYPE:
188 type_code_string = "union";
189 break;
190
191 case ENUMERAL_TYPE:
192 type_code_string = "enum";
193 break;
194
195 case VOID_TYPE:
196 error ("invalid use of void expression");
197 return;
198
199 case ARRAY_TYPE:
200 if (TYPE_DOMAIN (type))
201 {
202 if (TYPE_MAX_VALUE (TYPE_DOMAIN (type)) == NULL)
203 {
204 error ("invalid use of flexible array member");
205 return;
206 }
207 type = TREE_TYPE (type);
208 goto retry;
209 }
210 error ("invalid use of array with unspecified bounds");
211 return;
212
213 default:
214 gcc_unreachable ();
215 }
216
217 if (TREE_CODE (TYPE_NAME (type)) == IDENTIFIER_NODE)
218 error ("invalid use of undefined type %<%s %E%>",
219 type_code_string, TYPE_NAME (type));
220 else
221 /* If this type has a typedef-name, the TYPE_NAME is a TYPE_DECL. */
222 error ("invalid use of incomplete typedef %qD", TYPE_NAME (type));
223 }
224 }
225
226 /* Given a type, apply default promotions wrt unnamed function
227 arguments and return the new type. */
228
229 tree
230 c_type_promotes_to (tree type)
231 {
232 if (TYPE_MAIN_VARIANT (type) == float_type_node)
233 return double_type_node;
234
235 if (c_promoting_integer_type_p (type))
236 {
237 /* Preserve unsignedness if not really getting any wider. */
238 if (TYPE_UNSIGNED (type)
239 && (TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node)))
240 return unsigned_type_node;
241 return integer_type_node;
242 }
243
244 return type;
245 }
246
247 /* Return a variant of TYPE which has all the type qualifiers of LIKE
248 as well as those of TYPE. */
249
250 static tree
251 qualify_type (tree type, tree like)
252 {
253 return c_build_qualified_type (type,
254 TYPE_QUALS (type) | TYPE_QUALS (like));
255 }
256
257 /* Return true iff the given tree T is a variable length array. */
258
259 bool
260 c_vla_type_p (tree t)
261 {
262 if (TREE_CODE (t) == ARRAY_TYPE
263 && C_TYPE_VARIABLE_SIZE (t))
264 return true;
265 return false;
266 }
267 \f
268 /* Return the composite type of two compatible types.
269
270 We assume that comptypes has already been done and returned
271 nonzero; if that isn't so, this may crash. In particular, we
272 assume that qualifiers match. */
273
274 tree
275 composite_type (tree t1, tree t2)
276 {
277 enum tree_code code1;
278 enum tree_code code2;
279 tree attributes;
280
281 /* Save time if the two types are the same. */
282
283 if (t1 == t2) return t1;
284
285 /* If one type is nonsense, use the other. */
286 if (t1 == error_mark_node)
287 return t2;
288 if (t2 == error_mark_node)
289 return t1;
290
291 code1 = TREE_CODE (t1);
292 code2 = TREE_CODE (t2);
293
294 /* Merge the attributes. */
295 attributes = targetm.merge_type_attributes (t1, t2);
296
297 /* If one is an enumerated type and the other is the compatible
298 integer type, the composite type might be either of the two
299 (DR#013 question 3). For consistency, use the enumerated type as
300 the composite type. */
301
302 if (code1 == ENUMERAL_TYPE && code2 == INTEGER_TYPE)
303 return t1;
304 if (code2 == ENUMERAL_TYPE && code1 == INTEGER_TYPE)
305 return t2;
306
307 gcc_assert (code1 == code2);
308
309 switch (code1)
310 {
311 case POINTER_TYPE:
312 /* For two pointers, do this recursively on the target type. */
313 {
314 tree pointed_to_1 = TREE_TYPE (t1);
315 tree pointed_to_2 = TREE_TYPE (t2);
316 tree target = composite_type (pointed_to_1, pointed_to_2);
317 t1 = build_pointer_type (target);
318 t1 = build_type_attribute_variant (t1, attributes);
319 return qualify_type (t1, t2);
320 }
321
322 case ARRAY_TYPE:
323 {
324 tree elt = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
325 int quals;
326 tree unqual_elt;
327 tree d1 = TYPE_DOMAIN (t1);
328 tree d2 = TYPE_DOMAIN (t2);
329 bool d1_variable, d2_variable;
330 bool d1_zero, d2_zero;
331
332 /* We should not have any type quals on arrays at all. */
333 gcc_assert (!TYPE_QUALS (t1) && !TYPE_QUALS (t2));
334
335 d1_zero = d1 == 0 || !TYPE_MAX_VALUE (d1);
336 d2_zero = d2 == 0 || !TYPE_MAX_VALUE (d2);
337
338 d1_variable = (!d1_zero
339 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
340 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
341 d2_variable = (!d2_zero
342 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
343 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
344 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1));
345 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2));
346
347 /* Save space: see if the result is identical to one of the args. */
348 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1)
349 && (d2_variable || d2_zero || !d1_variable))
350 return build_type_attribute_variant (t1, attributes);
351 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2)
352 && (d1_variable || d1_zero || !d2_variable))
353 return build_type_attribute_variant (t2, attributes);
354
355 if (elt == TREE_TYPE (t1) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
356 return build_type_attribute_variant (t1, attributes);
357 if (elt == TREE_TYPE (t2) && !TYPE_DOMAIN (t2) && !TYPE_DOMAIN (t1))
358 return build_type_attribute_variant (t2, attributes);
359
360 /* Merge the element types, and have a size if either arg has
361 one. We may have qualifiers on the element types. To set
362 up TYPE_MAIN_VARIANT correctly, we need to form the
363 composite of the unqualified types and add the qualifiers
364 back at the end. */
365 quals = TYPE_QUALS (strip_array_types (elt));
366 unqual_elt = c_build_qualified_type (elt, TYPE_UNQUALIFIED);
367 t1 = build_array_type (unqual_elt,
368 TYPE_DOMAIN ((TYPE_DOMAIN (t1)
369 && (d2_variable
370 || d2_zero
371 || !d1_variable))
372 ? t1
373 : t2));
374 t1 = c_build_qualified_type (t1, quals);
375 return build_type_attribute_variant (t1, attributes);
376 }
377
378 case ENUMERAL_TYPE:
379 case RECORD_TYPE:
380 case UNION_TYPE:
381 if (attributes != NULL)
382 {
383 /* Try harder not to create a new aggregate type. */
384 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
385 return t1;
386 if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
387 return t2;
388 }
389 return build_type_attribute_variant (t1, attributes);
390
391 case FUNCTION_TYPE:
392 /* Function types: prefer the one that specified arg types.
393 If both do, merge the arg types. Also merge the return types. */
394 {
395 tree valtype = composite_type (TREE_TYPE (t1), TREE_TYPE (t2));
396 tree p1 = TYPE_ARG_TYPES (t1);
397 tree p2 = TYPE_ARG_TYPES (t2);
398 int len;
399 tree newargs, n;
400 int i;
401
402 /* Save space: see if the result is identical to one of the args. */
403 if (valtype == TREE_TYPE (t1) && !TYPE_ARG_TYPES (t2))
404 return build_type_attribute_variant (t1, attributes);
405 if (valtype == TREE_TYPE (t2) && !TYPE_ARG_TYPES (t1))
406 return build_type_attribute_variant (t2, attributes);
407
408 /* Simple way if one arg fails to specify argument types. */
409 if (TYPE_ARG_TYPES (t1) == 0)
410 {
411 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t2));
412 t1 = build_type_attribute_variant (t1, attributes);
413 return qualify_type (t1, t2);
414 }
415 if (TYPE_ARG_TYPES (t2) == 0)
416 {
417 t1 = build_function_type (valtype, TYPE_ARG_TYPES (t1));
418 t1 = build_type_attribute_variant (t1, attributes);
419 return qualify_type (t1, t2);
420 }
421
422 /* If both args specify argument types, we must merge the two
423 lists, argument by argument. */
424 /* Tell global_bindings_p to return false so that variable_size
425 doesn't die on VLAs in parameter types. */
426 c_override_global_bindings_to_false = true;
427
428 len = list_length (p1);
429 newargs = 0;
430
431 for (i = 0; i < len; i++)
432 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
433
434 n = newargs;
435
436 for (; p1;
437 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n))
438 {
439 /* A null type means arg type is not specified.
440 Take whatever the other function type has. */
441 if (TREE_VALUE (p1) == 0)
442 {
443 TREE_VALUE (n) = TREE_VALUE (p2);
444 goto parm_done;
445 }
446 if (TREE_VALUE (p2) == 0)
447 {
448 TREE_VALUE (n) = TREE_VALUE (p1);
449 goto parm_done;
450 }
451
452 /* Given wait (union {union wait *u; int *i} *)
453 and wait (union wait *),
454 prefer union wait * as type of parm. */
455 if (TREE_CODE (TREE_VALUE (p1)) == UNION_TYPE
456 && TREE_VALUE (p1) != TREE_VALUE (p2))
457 {
458 tree memb;
459 tree mv2 = TREE_VALUE (p2);
460 if (mv2 && mv2 != error_mark_node
461 && TREE_CODE (mv2) != ARRAY_TYPE)
462 mv2 = TYPE_MAIN_VARIANT (mv2);
463 for (memb = TYPE_FIELDS (TREE_VALUE (p1));
464 memb; memb = TREE_CHAIN (memb))
465 {
466 tree mv3 = TREE_TYPE (memb);
467 if (mv3 && mv3 != error_mark_node
468 && TREE_CODE (mv3) != ARRAY_TYPE)
469 mv3 = TYPE_MAIN_VARIANT (mv3);
470 if (comptypes (mv3, mv2))
471 {
472 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
473 TREE_VALUE (p2));
474 if (pedantic)
475 pedwarn ("function types not truly compatible in ISO C");
476 goto parm_done;
477 }
478 }
479 }
480 if (TREE_CODE (TREE_VALUE (p2)) == UNION_TYPE
481 && TREE_VALUE (p2) != TREE_VALUE (p1))
482 {
483 tree memb;
484 tree mv1 = TREE_VALUE (p1);
485 if (mv1 && mv1 != error_mark_node
486 && TREE_CODE (mv1) != ARRAY_TYPE)
487 mv1 = TYPE_MAIN_VARIANT (mv1);
488 for (memb = TYPE_FIELDS (TREE_VALUE (p2));
489 memb; memb = TREE_CHAIN (memb))
490 {
491 tree mv3 = TREE_TYPE (memb);
492 if (mv3 && mv3 != error_mark_node
493 && TREE_CODE (mv3) != ARRAY_TYPE)
494 mv3 = TYPE_MAIN_VARIANT (mv3);
495 if (comptypes (mv3, mv1))
496 {
497 TREE_VALUE (n) = composite_type (TREE_TYPE (memb),
498 TREE_VALUE (p1));
499 if (pedantic)
500 pedwarn ("function types not truly compatible in ISO C");
501 goto parm_done;
502 }
503 }
504 }
505 TREE_VALUE (n) = composite_type (TREE_VALUE (p1), TREE_VALUE (p2));
506 parm_done: ;
507 }
508
509 c_override_global_bindings_to_false = false;
510 t1 = build_function_type (valtype, newargs);
511 t1 = qualify_type (t1, t2);
512 /* ... falls through ... */
513 }
514
515 default:
516 return build_type_attribute_variant (t1, attributes);
517 }
518
519 }
520
521 /* Return the type of a conditional expression between pointers to
522 possibly differently qualified versions of compatible types.
523
524 We assume that comp_target_types has already been done and returned
525 nonzero; if that isn't so, this may crash. */
526
527 static tree
528 common_pointer_type (tree t1, tree t2)
529 {
530 tree attributes;
531 tree pointed_to_1, mv1;
532 tree pointed_to_2, mv2;
533 tree target;
534
535 /* Save time if the two types are the same. */
536
537 if (t1 == t2) return t1;
538
539 /* If one type is nonsense, use the other. */
540 if (t1 == error_mark_node)
541 return t2;
542 if (t2 == error_mark_node)
543 return t1;
544
545 gcc_assert (TREE_CODE (t1) == POINTER_TYPE
546 && TREE_CODE (t2) == POINTER_TYPE);
547
548 /* Merge the attributes. */
549 attributes = targetm.merge_type_attributes (t1, t2);
550
551 /* Find the composite type of the target types, and combine the
552 qualifiers of the two types' targets. Do not lose qualifiers on
553 array element types by taking the TYPE_MAIN_VARIANT. */
554 mv1 = pointed_to_1 = TREE_TYPE (t1);
555 mv2 = pointed_to_2 = TREE_TYPE (t2);
556 if (TREE_CODE (mv1) != ARRAY_TYPE)
557 mv1 = TYPE_MAIN_VARIANT (pointed_to_1);
558 if (TREE_CODE (mv2) != ARRAY_TYPE)
559 mv2 = TYPE_MAIN_VARIANT (pointed_to_2);
560 target = composite_type (mv1, mv2);
561 t1 = build_pointer_type (c_build_qualified_type
562 (target,
563 TYPE_QUALS (pointed_to_1) |
564 TYPE_QUALS (pointed_to_2)));
565 return build_type_attribute_variant (t1, attributes);
566 }
567
568 /* Return the common type for two arithmetic types under the usual
569 arithmetic conversions. The default conversions have already been
570 applied, and enumerated types converted to their compatible integer
571 types. The resulting type is unqualified and has no attributes.
572
573 This is the type for the result of most arithmetic operations
574 if the operands have the given two types. */
575
576 static tree
577 c_common_type (tree t1, tree t2)
578 {
579 enum tree_code code1;
580 enum tree_code code2;
581
582 /* If one type is nonsense, use the other. */
583 if (t1 == error_mark_node)
584 return t2;
585 if (t2 == error_mark_node)
586 return t1;
587
588 if (TYPE_QUALS (t1) != TYPE_UNQUALIFIED)
589 t1 = TYPE_MAIN_VARIANT (t1);
590
591 if (TYPE_QUALS (t2) != TYPE_UNQUALIFIED)
592 t2 = TYPE_MAIN_VARIANT (t2);
593
594 if (TYPE_ATTRIBUTES (t1) != NULL_TREE)
595 t1 = build_type_attribute_variant (t1, NULL_TREE);
596
597 if (TYPE_ATTRIBUTES (t2) != NULL_TREE)
598 t2 = build_type_attribute_variant (t2, NULL_TREE);
599
600 /* Save time if the two types are the same. */
601
602 if (t1 == t2) return t1;
603
604 code1 = TREE_CODE (t1);
605 code2 = TREE_CODE (t2);
606
607 gcc_assert (code1 == VECTOR_TYPE || code1 == COMPLEX_TYPE
608 || code1 == REAL_TYPE || code1 == INTEGER_TYPE);
609 gcc_assert (code2 == VECTOR_TYPE || code2 == COMPLEX_TYPE
610 || code2 == REAL_TYPE || code2 == INTEGER_TYPE);
611
612 /* When one operand is a decimal float type, the other operand cannot be
613 a generic float type or a complex type. We also disallow vector types
614 here. */
615 if ((DECIMAL_FLOAT_TYPE_P (t1) || DECIMAL_FLOAT_TYPE_P (t2))
616 && !(DECIMAL_FLOAT_TYPE_P (t1) && DECIMAL_FLOAT_TYPE_P (t2)))
617 {
618 if (code1 == VECTOR_TYPE || code2 == VECTOR_TYPE)
619 {
620 error ("can%'t mix operands of decimal float and vector types");
621 return error_mark_node;
622 }
623 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
624 {
625 error ("can%'t mix operands of decimal float and complex types");
626 return error_mark_node;
627 }
628 if (code1 == REAL_TYPE && code2 == REAL_TYPE)
629 {
630 error ("can%'t mix operands of decimal float and other float types");
631 return error_mark_node;
632 }
633 }
634
635 /* If one type is a vector type, return that type. (How the usual
636 arithmetic conversions apply to the vector types extension is not
637 precisely specified.) */
638 if (code1 == VECTOR_TYPE)
639 return t1;
640
641 if (code2 == VECTOR_TYPE)
642 return t2;
643
644 /* If one type is complex, form the common type of the non-complex
645 components, then make that complex. Use T1 or T2 if it is the
646 required type. */
647 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
648 {
649 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
650 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
651 tree subtype = c_common_type (subtype1, subtype2);
652
653 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
654 return t1;
655 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
656 return t2;
657 else
658 return build_complex_type (subtype);
659 }
660
661 /* If only one is real, use it as the result. */
662
663 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
664 return t1;
665
666 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
667 return t2;
668
669 /* If both are real and either are decimal floating point types, use
670 the decimal floating point type with the greater precision. */
671
672 if (code1 == REAL_TYPE && code2 == REAL_TYPE)
673 {
674 if (TYPE_MAIN_VARIANT (t1) == dfloat128_type_node
675 || TYPE_MAIN_VARIANT (t2) == dfloat128_type_node)
676 return dfloat128_type_node;
677 else if (TYPE_MAIN_VARIANT (t1) == dfloat64_type_node
678 || TYPE_MAIN_VARIANT (t2) == dfloat64_type_node)
679 return dfloat64_type_node;
680 else if (TYPE_MAIN_VARIANT (t1) == dfloat32_type_node
681 || TYPE_MAIN_VARIANT (t2) == dfloat32_type_node)
682 return dfloat32_type_node;
683 }
684
685 /* Both real or both integers; use the one with greater precision. */
686
687 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
688 return t1;
689 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
690 return t2;
691
692 /* Same precision. Prefer long longs to longs to ints when the
693 same precision, following the C99 rules on integer type rank
694 (which are equivalent to the C90 rules for C90 types). */
695
696 if (TYPE_MAIN_VARIANT (t1) == long_long_unsigned_type_node
697 || TYPE_MAIN_VARIANT (t2) == long_long_unsigned_type_node)
698 return long_long_unsigned_type_node;
699
700 if (TYPE_MAIN_VARIANT (t1) == long_long_integer_type_node
701 || TYPE_MAIN_VARIANT (t2) == long_long_integer_type_node)
702 {
703 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
704 return long_long_unsigned_type_node;
705 else
706 return long_long_integer_type_node;
707 }
708
709 if (TYPE_MAIN_VARIANT (t1) == long_unsigned_type_node
710 || TYPE_MAIN_VARIANT (t2) == long_unsigned_type_node)
711 return long_unsigned_type_node;
712
713 if (TYPE_MAIN_VARIANT (t1) == long_integer_type_node
714 || TYPE_MAIN_VARIANT (t2) == long_integer_type_node)
715 {
716 /* But preserve unsignedness from the other type,
717 since long cannot hold all the values of an unsigned int. */
718 if (TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
719 return long_unsigned_type_node;
720 else
721 return long_integer_type_node;
722 }
723
724 /* Likewise, prefer long double to double even if same size. */
725 if (TYPE_MAIN_VARIANT (t1) == long_double_type_node
726 || TYPE_MAIN_VARIANT (t2) == long_double_type_node)
727 return long_double_type_node;
728
729 /* Otherwise prefer the unsigned one. */
730
731 if (TYPE_UNSIGNED (t1))
732 return t1;
733 else
734 return t2;
735 }
736 \f
737 /* Wrapper around c_common_type that is used by c-common.c and other
738 front end optimizations that remove promotions. ENUMERAL_TYPEs
739 are allowed here and are converted to their compatible integer types.
740 BOOLEAN_TYPEs are allowed here and return either boolean_type_node or
741 preferably a non-Boolean type as the common type. */
742 tree
743 common_type (tree t1, tree t2)
744 {
745 if (TREE_CODE (t1) == ENUMERAL_TYPE)
746 t1 = c_common_type_for_size (TYPE_PRECISION (t1), 1);
747 if (TREE_CODE (t2) == ENUMERAL_TYPE)
748 t2 = c_common_type_for_size (TYPE_PRECISION (t2), 1);
749
750 /* If both types are BOOLEAN_TYPE, then return boolean_type_node. */
751 if (TREE_CODE (t1) == BOOLEAN_TYPE
752 && TREE_CODE (t2) == BOOLEAN_TYPE)
753 return boolean_type_node;
754
755 /* If either type is BOOLEAN_TYPE, then return the other. */
756 if (TREE_CODE (t1) == BOOLEAN_TYPE)
757 return t2;
758 if (TREE_CODE (t2) == BOOLEAN_TYPE)
759 return t1;
760
761 return c_common_type (t1, t2);
762 }
763
764 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
765 or various other operations. Return 2 if they are compatible
766 but a warning may be needed if you use them together. */
767
768 int
769 comptypes (tree type1, tree type2)
770 {
771 const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base;
772 int val;
773
774 val = comptypes_internal (type1, type2);
775 free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1);
776
777 return val;
778 }
779 \f
780 /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment
781 or various other operations. Return 2 if they are compatible
782 but a warning may be needed if you use them together. This
783 differs from comptypes, in that we don't free the seen types. */
784
785 static int
786 comptypes_internal (tree type1, tree type2)
787 {
788 tree t1 = type1;
789 tree t2 = type2;
790 int attrval, val;
791
792 /* Suppress errors caused by previously reported errors. */
793
794 if (t1 == t2 || !t1 || !t2
795 || TREE_CODE (t1) == ERROR_MARK || TREE_CODE (t2) == ERROR_MARK)
796 return 1;
797
798 /* If either type is the internal version of sizetype, return the
799 language version. */
800 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
801 && TYPE_ORIG_SIZE_TYPE (t1))
802 t1 = TYPE_ORIG_SIZE_TYPE (t1);
803
804 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
805 && TYPE_ORIG_SIZE_TYPE (t2))
806 t2 = TYPE_ORIG_SIZE_TYPE (t2);
807
808
809 /* Enumerated types are compatible with integer types, but this is
810 not transitive: two enumerated types in the same translation unit
811 are compatible with each other only if they are the same type. */
812
813 if (TREE_CODE (t1) == ENUMERAL_TYPE && TREE_CODE (t2) != ENUMERAL_TYPE)
814 t1 = c_common_type_for_size (TYPE_PRECISION (t1), TYPE_UNSIGNED (t1));
815 else if (TREE_CODE (t2) == ENUMERAL_TYPE && TREE_CODE (t1) != ENUMERAL_TYPE)
816 t2 = c_common_type_for_size (TYPE_PRECISION (t2), TYPE_UNSIGNED (t2));
817
818 if (t1 == t2)
819 return 1;
820
821 /* Different classes of types can't be compatible. */
822
823 if (TREE_CODE (t1) != TREE_CODE (t2))
824 return 0;
825
826 /* Qualifiers must match. C99 6.7.3p9 */
827
828 if (TYPE_QUALS (t1) != TYPE_QUALS (t2))
829 return 0;
830
831 /* Allow for two different type nodes which have essentially the same
832 definition. Note that we already checked for equality of the type
833 qualifiers (just above). */
834
835 if (TREE_CODE (t1) != ARRAY_TYPE
836 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
837 return 1;
838
839 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
840 if (!(attrval = targetm.comp_type_attributes (t1, t2)))
841 return 0;
842
843 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
844 val = 0;
845
846 switch (TREE_CODE (t1))
847 {
848 case POINTER_TYPE:
849 /* Do not remove mode or aliasing information. */
850 if (TYPE_MODE (t1) != TYPE_MODE (t2)
851 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2))
852 break;
853 val = (TREE_TYPE (t1) == TREE_TYPE (t2)
854 ? 1 : comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2)));
855 break;
856
857 case FUNCTION_TYPE:
858 val = function_types_compatible_p (t1, t2);
859 break;
860
861 case ARRAY_TYPE:
862 {
863 tree d1 = TYPE_DOMAIN (t1);
864 tree d2 = TYPE_DOMAIN (t2);
865 bool d1_variable, d2_variable;
866 bool d1_zero, d2_zero;
867 val = 1;
868
869 /* Target types must match incl. qualifiers. */
870 if (TREE_TYPE (t1) != TREE_TYPE (t2)
871 && 0 == (val = comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2))))
872 return 0;
873
874 /* Sizes must match unless one is missing or variable. */
875 if (d1 == 0 || d2 == 0 || d1 == d2)
876 break;
877
878 d1_zero = !TYPE_MAX_VALUE (d1);
879 d2_zero = !TYPE_MAX_VALUE (d2);
880
881 d1_variable = (!d1_zero
882 && (TREE_CODE (TYPE_MIN_VALUE (d1)) != INTEGER_CST
883 || TREE_CODE (TYPE_MAX_VALUE (d1)) != INTEGER_CST));
884 d2_variable = (!d2_zero
885 && (TREE_CODE (TYPE_MIN_VALUE (d2)) != INTEGER_CST
886 || TREE_CODE (TYPE_MAX_VALUE (d2)) != INTEGER_CST));
887 d1_variable = d1_variable || (d1_zero && c_vla_type_p (t1));
888 d2_variable = d2_variable || (d2_zero && c_vla_type_p (t2));
889
890 if (d1_variable || d2_variable)
891 break;
892 if (d1_zero && d2_zero)
893 break;
894 if (d1_zero || d2_zero
895 || !tree_int_cst_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
896 || !tree_int_cst_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)))
897 val = 0;
898
899 break;
900 }
901
902 case ENUMERAL_TYPE:
903 case RECORD_TYPE:
904 case UNION_TYPE:
905 if (val != 1 && !same_translation_unit_p (t1, t2))
906 {
907 tree a1 = TYPE_ATTRIBUTES (t1);
908 tree a2 = TYPE_ATTRIBUTES (t2);
909
910 if (! attribute_list_contained (a1, a2)
911 && ! attribute_list_contained (a2, a1))
912 break;
913
914 if (attrval != 2)
915 return tagged_types_tu_compatible_p (t1, t2);
916 val = tagged_types_tu_compatible_p (t1, t2);
917 }
918 break;
919
920 case VECTOR_TYPE:
921 val = TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
922 && comptypes_internal (TREE_TYPE (t1), TREE_TYPE (t2));
923 break;
924
925 default:
926 break;
927 }
928 return attrval == 2 && val == 1 ? 2 : val;
929 }
930
931 /* Return 1 if TTL and TTR are pointers to types that are equivalent,
932 ignoring their qualifiers. */
933
934 static int
935 comp_target_types (tree ttl, tree ttr)
936 {
937 int val;
938 tree mvl, mvr;
939
940 /* Do not lose qualifiers on element types of array types that are
941 pointer targets by taking their TYPE_MAIN_VARIANT. */
942 mvl = TREE_TYPE (ttl);
943 mvr = TREE_TYPE (ttr);
944 if (TREE_CODE (mvl) != ARRAY_TYPE)
945 mvl = TYPE_MAIN_VARIANT (mvl);
946 if (TREE_CODE (mvr) != ARRAY_TYPE)
947 mvr = TYPE_MAIN_VARIANT (mvr);
948 val = comptypes (mvl, mvr);
949
950 if (val == 2 && pedantic)
951 pedwarn ("types are not quite compatible");
952 return val;
953 }
954 \f
955 /* Subroutines of `comptypes'. */
956
957 /* Determine whether two trees derive from the same translation unit.
958 If the CONTEXT chain ends in a null, that tree's context is still
959 being parsed, so if two trees have context chains ending in null,
960 they're in the same translation unit. */
961 int
962 same_translation_unit_p (tree t1, tree t2)
963 {
964 while (t1 && TREE_CODE (t1) != TRANSLATION_UNIT_DECL)
965 switch (TREE_CODE_CLASS (TREE_CODE (t1)))
966 {
967 case tcc_declaration:
968 t1 = DECL_CONTEXT (t1); break;
969 case tcc_type:
970 t1 = TYPE_CONTEXT (t1); break;
971 case tcc_exceptional:
972 t1 = BLOCK_SUPERCONTEXT (t1); break; /* assume block */
973 default: gcc_unreachable ();
974 }
975
976 while (t2 && TREE_CODE (t2) != TRANSLATION_UNIT_DECL)
977 switch (TREE_CODE_CLASS (TREE_CODE (t2)))
978 {
979 case tcc_declaration:
980 t2 = DECL_CONTEXT (t2); break;
981 case tcc_type:
982 t2 = TYPE_CONTEXT (t2); break;
983 case tcc_exceptional:
984 t2 = BLOCK_SUPERCONTEXT (t2); break; /* assume block */
985 default: gcc_unreachable ();
986 }
987
988 return t1 == t2;
989 }
990
991 /* Allocate the seen two types, assuming that they are compatible. */
992
993 static struct tagged_tu_seen_cache *
994 alloc_tagged_tu_seen_cache (tree t1, tree t2)
995 {
996 struct tagged_tu_seen_cache *tu = XNEW (struct tagged_tu_seen_cache);
997 tu->next = tagged_tu_seen_base;
998 tu->t1 = t1;
999 tu->t2 = t2;
1000
1001 tagged_tu_seen_base = tu;
1002
1003 /* The C standard says that two structures in different translation
1004 units are compatible with each other only if the types of their
1005 fields are compatible (among other things). We assume that they
1006 are compatible until proven otherwise when building the cache.
1007 An example where this can occur is:
1008 struct a
1009 {
1010 struct a *next;
1011 };
1012 If we are comparing this against a similar struct in another TU,
1013 and did not assume they were compatible, we end up with an infinite
1014 loop. */
1015 tu->val = 1;
1016 return tu;
1017 }
1018
1019 /* Free the seen types until we get to TU_TIL. */
1020
1021 static void
1022 free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *tu_til)
1023 {
1024 const struct tagged_tu_seen_cache *tu = tagged_tu_seen_base;
1025 while (tu != tu_til)
1026 {
1027 struct tagged_tu_seen_cache *tu1 = (struct tagged_tu_seen_cache*)tu;
1028 tu = tu1->next;
1029 free (tu1);
1030 }
1031 tagged_tu_seen_base = tu_til;
1032 }
1033
1034 /* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are
1035 compatible. If the two types are not the same (which has been
1036 checked earlier), this can only happen when multiple translation
1037 units are being compiled. See C99 6.2.7 paragraph 1 for the exact
1038 rules. */
1039
1040 static int
1041 tagged_types_tu_compatible_p (tree t1, tree t2)
1042 {
1043 tree s1, s2;
1044 bool needs_warning = false;
1045
1046 /* We have to verify that the tags of the types are the same. This
1047 is harder than it looks because this may be a typedef, so we have
1048 to go look at the original type. It may even be a typedef of a
1049 typedef...
1050 In the case of compiler-created builtin structs the TYPE_DECL
1051 may be a dummy, with no DECL_ORIGINAL_TYPE. Don't fault. */
1052 while (TYPE_NAME (t1)
1053 && TREE_CODE (TYPE_NAME (t1)) == TYPE_DECL
1054 && DECL_ORIGINAL_TYPE (TYPE_NAME (t1)))
1055 t1 = DECL_ORIGINAL_TYPE (TYPE_NAME (t1));
1056
1057 while (TYPE_NAME (t2)
1058 && TREE_CODE (TYPE_NAME (t2)) == TYPE_DECL
1059 && DECL_ORIGINAL_TYPE (TYPE_NAME (t2)))
1060 t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2));
1061
1062 /* C90 didn't have the requirement that the two tags be the same. */
1063 if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2))
1064 return 0;
1065
1066 /* C90 didn't say what happened if one or both of the types were
1067 incomplete; we choose to follow C99 rules here, which is that they
1068 are compatible. */
1069 if (TYPE_SIZE (t1) == NULL
1070 || TYPE_SIZE (t2) == NULL)
1071 return 1;
1072
1073 {
1074 const struct tagged_tu_seen_cache * tts_i;
1075 for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next)
1076 if (tts_i->t1 == t1 && tts_i->t2 == t2)
1077 return tts_i->val;
1078 }
1079
1080 switch (TREE_CODE (t1))
1081 {
1082 case ENUMERAL_TYPE:
1083 {
1084 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1085 /* Speed up the case where the type values are in the same order. */
1086 tree tv1 = TYPE_VALUES (t1);
1087 tree tv2 = TYPE_VALUES (t2);
1088
1089 if (tv1 == tv2)
1090 {
1091 return 1;
1092 }
1093
1094 for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2))
1095 {
1096 if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2))
1097 break;
1098 if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1)
1099 {
1100 tu->val = 0;
1101 return 0;
1102 }
1103 }
1104
1105 if (tv1 == NULL_TREE && tv2 == NULL_TREE)
1106 {
1107 return 1;
1108 }
1109 if (tv1 == NULL_TREE || tv2 == NULL_TREE)
1110 {
1111 tu->val = 0;
1112 return 0;
1113 }
1114
1115 if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2)))
1116 {
1117 tu->val = 0;
1118 return 0;
1119 }
1120
1121 for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1))
1122 {
1123 s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2));
1124 if (s2 == NULL
1125 || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1)
1126 {
1127 tu->val = 0;
1128 return 0;
1129 }
1130 }
1131 return 1;
1132 }
1133
1134 case UNION_TYPE:
1135 {
1136 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1137 if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2)))
1138 {
1139 tu->val = 0;
1140 return 0;
1141 }
1142
1143 /* Speed up the common case where the fields are in the same order. */
1144 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2); s1 && s2;
1145 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1146 {
1147 int result;
1148
1149
1150 if (DECL_NAME (s1) == NULL
1151 || DECL_NAME (s1) != DECL_NAME (s2))
1152 break;
1153 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2));
1154 if (result == 0)
1155 {
1156 tu->val = 0;
1157 return 0;
1158 }
1159 if (result == 2)
1160 needs_warning = true;
1161
1162 if (TREE_CODE (s1) == FIELD_DECL
1163 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1164 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1165 {
1166 tu->val = 0;
1167 return 0;
1168 }
1169 }
1170 if (!s1 && !s2)
1171 {
1172 tu->val = needs_warning ? 2 : 1;
1173 return tu->val;
1174 }
1175
1176 for (s1 = TYPE_FIELDS (t1); s1; s1 = TREE_CHAIN (s1))
1177 {
1178 bool ok = false;
1179
1180 if (DECL_NAME (s1) != NULL)
1181 for (s2 = TYPE_FIELDS (t2); s2; s2 = TREE_CHAIN (s2))
1182 if (DECL_NAME (s1) == DECL_NAME (s2))
1183 {
1184 int result;
1185 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2));
1186 if (result == 0)
1187 {
1188 tu->val = 0;
1189 return 0;
1190 }
1191 if (result == 2)
1192 needs_warning = true;
1193
1194 if (TREE_CODE (s1) == FIELD_DECL
1195 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1196 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1197 break;
1198
1199 ok = true;
1200 break;
1201 }
1202 if (!ok)
1203 {
1204 tu->val = 0;
1205 return 0;
1206 }
1207 }
1208 tu->val = needs_warning ? 2 : 10;
1209 return tu->val;
1210 }
1211
1212 case RECORD_TYPE:
1213 {
1214 struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2);
1215
1216 for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2);
1217 s1 && s2;
1218 s1 = TREE_CHAIN (s1), s2 = TREE_CHAIN (s2))
1219 {
1220 int result;
1221 if (TREE_CODE (s1) != TREE_CODE (s2)
1222 || DECL_NAME (s1) != DECL_NAME (s2))
1223 break;
1224 result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2));
1225 if (result == 0)
1226 break;
1227 if (result == 2)
1228 needs_warning = true;
1229
1230 if (TREE_CODE (s1) == FIELD_DECL
1231 && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1),
1232 DECL_FIELD_BIT_OFFSET (s2)) != 1)
1233 break;
1234 }
1235 if (s1 && s2)
1236 tu->val = 0;
1237 else
1238 tu->val = needs_warning ? 2 : 1;
1239 return tu->val;
1240 }
1241
1242 default:
1243 gcc_unreachable ();
1244 }
1245 }
1246
1247 /* Return 1 if two function types F1 and F2 are compatible.
1248 If either type specifies no argument types,
1249 the other must specify a fixed number of self-promoting arg types.
1250 Otherwise, if one type specifies only the number of arguments,
1251 the other must specify that number of self-promoting arg types.
1252 Otherwise, the argument types must match. */
1253
1254 static int
1255 function_types_compatible_p (tree f1, tree f2)
1256 {
1257 tree args1, args2;
1258 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1259 int val = 1;
1260 int val1;
1261 tree ret1, ret2;
1262
1263 ret1 = TREE_TYPE (f1);
1264 ret2 = TREE_TYPE (f2);
1265
1266 /* 'volatile' qualifiers on a function's return type used to mean
1267 the function is noreturn. */
1268 if (TYPE_VOLATILE (ret1) != TYPE_VOLATILE (ret2))
1269 pedwarn ("function return types not compatible due to %<volatile%>");
1270 if (TYPE_VOLATILE (ret1))
1271 ret1 = build_qualified_type (TYPE_MAIN_VARIANT (ret1),
1272 TYPE_QUALS (ret1) & ~TYPE_QUAL_VOLATILE);
1273 if (TYPE_VOLATILE (ret2))
1274 ret2 = build_qualified_type (TYPE_MAIN_VARIANT (ret2),
1275 TYPE_QUALS (ret2) & ~TYPE_QUAL_VOLATILE);
1276 val = comptypes_internal (ret1, ret2);
1277 if (val == 0)
1278 return 0;
1279
1280 args1 = TYPE_ARG_TYPES (f1);
1281 args2 = TYPE_ARG_TYPES (f2);
1282
1283 /* An unspecified parmlist matches any specified parmlist
1284 whose argument types don't need default promotions. */
1285
1286 if (args1 == 0)
1287 {
1288 if (!self_promoting_args_p (args2))
1289 return 0;
1290 /* If one of these types comes from a non-prototype fn definition,
1291 compare that with the other type's arglist.
1292 If they don't match, ask for a warning (but no error). */
1293 if (TYPE_ACTUAL_ARG_TYPES (f1)
1294 && 1 != type_lists_compatible_p (args2, TYPE_ACTUAL_ARG_TYPES (f1)))
1295 val = 2;
1296 return val;
1297 }
1298 if (args2 == 0)
1299 {
1300 if (!self_promoting_args_p (args1))
1301 return 0;
1302 if (TYPE_ACTUAL_ARG_TYPES (f2)
1303 && 1 != type_lists_compatible_p (args1, TYPE_ACTUAL_ARG_TYPES (f2)))
1304 val = 2;
1305 return val;
1306 }
1307
1308 /* Both types have argument lists: compare them and propagate results. */
1309 val1 = type_lists_compatible_p (args1, args2);
1310 return val1 != 1 ? val1 : val;
1311 }
1312
1313 /* Check two lists of types for compatibility,
1314 returning 0 for incompatible, 1 for compatible,
1315 or 2 for compatible with warning. */
1316
1317 static int
1318 type_lists_compatible_p (tree args1, tree args2)
1319 {
1320 /* 1 if no need for warning yet, 2 if warning cause has been seen. */
1321 int val = 1;
1322 int newval = 0;
1323
1324 while (1)
1325 {
1326 tree a1, mv1, a2, mv2;
1327 if (args1 == 0 && args2 == 0)
1328 return val;
1329 /* If one list is shorter than the other,
1330 they fail to match. */
1331 if (args1 == 0 || args2 == 0)
1332 return 0;
1333 mv1 = a1 = TREE_VALUE (args1);
1334 mv2 = a2 = TREE_VALUE (args2);
1335 if (mv1 && mv1 != error_mark_node && TREE_CODE (mv1) != ARRAY_TYPE)
1336 mv1 = TYPE_MAIN_VARIANT (mv1);
1337 if (mv2 && mv2 != error_mark_node && TREE_CODE (mv2) != ARRAY_TYPE)
1338 mv2 = TYPE_MAIN_VARIANT (mv2);
1339 /* A null pointer instead of a type
1340 means there is supposed to be an argument
1341 but nothing is specified about what type it has.
1342 So match anything that self-promotes. */
1343 if (a1 == 0)
1344 {
1345 if (c_type_promotes_to (a2) != a2)
1346 return 0;
1347 }
1348 else if (a2 == 0)
1349 {
1350 if (c_type_promotes_to (a1) != a1)
1351 return 0;
1352 }
1353 /* If one of the lists has an error marker, ignore this arg. */
1354 else if (TREE_CODE (a1) == ERROR_MARK
1355 || TREE_CODE (a2) == ERROR_MARK)
1356 ;
1357 else if (!(newval = comptypes_internal (mv1, mv2)))
1358 {
1359 /* Allow wait (union {union wait *u; int *i} *)
1360 and wait (union wait *) to be compatible. */
1361 if (TREE_CODE (a1) == UNION_TYPE
1362 && (TYPE_NAME (a1) == 0
1363 || TYPE_TRANSPARENT_UNION (a1))
1364 && TREE_CODE (TYPE_SIZE (a1)) == INTEGER_CST
1365 && tree_int_cst_equal (TYPE_SIZE (a1),
1366 TYPE_SIZE (a2)))
1367 {
1368 tree memb;
1369 for (memb = TYPE_FIELDS (a1);
1370 memb; memb = TREE_CHAIN (memb))
1371 {
1372 tree mv3 = TREE_TYPE (memb);
1373 if (mv3 && mv3 != error_mark_node
1374 && TREE_CODE (mv3) != ARRAY_TYPE)
1375 mv3 = TYPE_MAIN_VARIANT (mv3);
1376 if (comptypes_internal (mv3, mv2))
1377 break;
1378 }
1379 if (memb == 0)
1380 return 0;
1381 }
1382 else if (TREE_CODE (a2) == UNION_TYPE
1383 && (TYPE_NAME (a2) == 0
1384 || TYPE_TRANSPARENT_UNION (a2))
1385 && TREE_CODE (TYPE_SIZE (a2)) == INTEGER_CST
1386 && tree_int_cst_equal (TYPE_SIZE (a2),
1387 TYPE_SIZE (a1)))
1388 {
1389 tree memb;
1390 for (memb = TYPE_FIELDS (a2);
1391 memb; memb = TREE_CHAIN (memb))
1392 {
1393 tree mv3 = TREE_TYPE (memb);
1394 if (mv3 && mv3 != error_mark_node
1395 && TREE_CODE (mv3) != ARRAY_TYPE)
1396 mv3 = TYPE_MAIN_VARIANT (mv3);
1397 if (comptypes_internal (mv3, mv1))
1398 break;
1399 }
1400 if (memb == 0)
1401 return 0;
1402 }
1403 else
1404 return 0;
1405 }
1406
1407 /* comptypes said ok, but record if it said to warn. */
1408 if (newval > val)
1409 val = newval;
1410
1411 args1 = TREE_CHAIN (args1);
1412 args2 = TREE_CHAIN (args2);
1413 }
1414 }
1415 \f
1416 /* Compute the size to increment a pointer by. */
1417
1418 static tree
1419 c_size_in_bytes (tree type)
1420 {
1421 enum tree_code code = TREE_CODE (type);
1422
1423 if (code == FUNCTION_TYPE || code == VOID_TYPE || code == ERROR_MARK)
1424 return size_one_node;
1425
1426 if (!COMPLETE_OR_VOID_TYPE_P (type))
1427 {
1428 error ("arithmetic on pointer to an incomplete type");
1429 return size_one_node;
1430 }
1431
1432 /* Convert in case a char is more than one unit. */
1433 return size_binop (CEIL_DIV_EXPR, TYPE_SIZE_UNIT (type),
1434 size_int (TYPE_PRECISION (char_type_node)
1435 / BITS_PER_UNIT));
1436 }
1437 \f
1438 /* Return either DECL or its known constant value (if it has one). */
1439
1440 tree
1441 decl_constant_value (tree decl)
1442 {
1443 if (/* Don't change a variable array bound or initial value to a constant
1444 in a place where a variable is invalid. Note that DECL_INITIAL
1445 isn't valid for a PARM_DECL. */
1446 current_function_decl != 0
1447 && TREE_CODE (decl) != PARM_DECL
1448 && !TREE_THIS_VOLATILE (decl)
1449 && TREE_READONLY (decl)
1450 && DECL_INITIAL (decl) != 0
1451 && TREE_CODE (DECL_INITIAL (decl)) != ERROR_MARK
1452 /* This is invalid if initial value is not constant.
1453 If it has either a function call, a memory reference,
1454 or a variable, then re-evaluating it could give different results. */
1455 && TREE_CONSTANT (DECL_INITIAL (decl))
1456 /* Check for cases where this is sub-optimal, even though valid. */
1457 && TREE_CODE (DECL_INITIAL (decl)) != CONSTRUCTOR)
1458 return DECL_INITIAL (decl);
1459 return decl;
1460 }
1461
1462 /* Return either DECL or its known constant value (if it has one), but
1463 return DECL if pedantic or DECL has mode BLKmode. This is for
1464 bug-compatibility with the old behavior of decl_constant_value
1465 (before GCC 3.0); every use of this function is a bug and it should
1466 be removed before GCC 3.1. It is not appropriate to use pedantic
1467 in a way that affects optimization, and BLKmode is probably not the
1468 right test for avoiding misoptimizations either. */
1469
1470 static tree
1471 decl_constant_value_for_broken_optimization (tree decl)
1472 {
1473 tree ret;
1474
1475 if (pedantic || DECL_MODE (decl) == BLKmode)
1476 return decl;
1477
1478 ret = decl_constant_value (decl);
1479 /* Avoid unwanted tree sharing between the initializer and current
1480 function's body where the tree can be modified e.g. by the
1481 gimplifier. */
1482 if (ret != decl && TREE_STATIC (decl))
1483 ret = unshare_expr (ret);
1484 return ret;
1485 }
1486
1487 /* Convert the array expression EXP to a pointer. */
1488 static tree
1489 array_to_pointer_conversion (tree exp)
1490 {
1491 tree orig_exp = exp;
1492 tree type = TREE_TYPE (exp);
1493 tree adr;
1494 tree restype = TREE_TYPE (type);
1495 tree ptrtype;
1496
1497 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
1498
1499 STRIP_TYPE_NOPS (exp);
1500
1501 if (TREE_NO_WARNING (orig_exp))
1502 TREE_NO_WARNING (exp) = 1;
1503
1504 ptrtype = build_pointer_type (restype);
1505
1506 if (TREE_CODE (exp) == INDIRECT_REF)
1507 return convert (ptrtype, TREE_OPERAND (exp, 0));
1508
1509 if (TREE_CODE (exp) == VAR_DECL)
1510 {
1511 /* We are making an ADDR_EXPR of ptrtype. This is a valid
1512 ADDR_EXPR because it's the best way of representing what
1513 happens in C when we take the address of an array and place
1514 it in a pointer to the element type. */
1515 adr = build1 (ADDR_EXPR, ptrtype, exp);
1516 if (!c_mark_addressable (exp))
1517 return error_mark_node;
1518 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1519 return adr;
1520 }
1521
1522 /* This way is better for a COMPONENT_REF since it can
1523 simplify the offset for a component. */
1524 adr = build_unary_op (ADDR_EXPR, exp, 1);
1525 return convert (ptrtype, adr);
1526 }
1527
1528 /* Convert the function expression EXP to a pointer. */
1529 static tree
1530 function_to_pointer_conversion (tree exp)
1531 {
1532 tree orig_exp = exp;
1533
1534 gcc_assert (TREE_CODE (TREE_TYPE (exp)) == FUNCTION_TYPE);
1535
1536 STRIP_TYPE_NOPS (exp);
1537
1538 if (TREE_NO_WARNING (orig_exp))
1539 TREE_NO_WARNING (exp) = 1;
1540
1541 return build_unary_op (ADDR_EXPR, exp, 0);
1542 }
1543
1544 /* Perform the default conversion of arrays and functions to pointers.
1545 Return the result of converting EXP. For any other expression, just
1546 return EXP after removing NOPs. */
1547
1548 struct c_expr
1549 default_function_array_conversion (struct c_expr exp)
1550 {
1551 tree orig_exp = exp.value;
1552 tree type = TREE_TYPE (exp.value);
1553 enum tree_code code = TREE_CODE (type);
1554
1555 switch (code)
1556 {
1557 case ARRAY_TYPE:
1558 {
1559 bool not_lvalue = false;
1560 bool lvalue_array_p;
1561
1562 while ((TREE_CODE (exp.value) == NON_LVALUE_EXPR
1563 || TREE_CODE (exp.value) == NOP_EXPR
1564 || TREE_CODE (exp.value) == CONVERT_EXPR)
1565 && TREE_TYPE (TREE_OPERAND (exp.value, 0)) == type)
1566 {
1567 if (TREE_CODE (exp.value) == NON_LVALUE_EXPR)
1568 not_lvalue = true;
1569 exp.value = TREE_OPERAND (exp.value, 0);
1570 }
1571
1572 if (TREE_NO_WARNING (orig_exp))
1573 TREE_NO_WARNING (exp.value) = 1;
1574
1575 lvalue_array_p = !not_lvalue && lvalue_p (exp.value);
1576 if (!flag_isoc99 && !lvalue_array_p)
1577 {
1578 /* Before C99, non-lvalue arrays do not decay to pointers.
1579 Normally, using such an array would be invalid; but it can
1580 be used correctly inside sizeof or as a statement expression.
1581 Thus, do not give an error here; an error will result later. */
1582 return exp;
1583 }
1584
1585 exp.value = array_to_pointer_conversion (exp.value);
1586 }
1587 break;
1588 case FUNCTION_TYPE:
1589 exp.value = function_to_pointer_conversion (exp.value);
1590 break;
1591 default:
1592 STRIP_TYPE_NOPS (exp.value);
1593 if (TREE_NO_WARNING (orig_exp))
1594 TREE_NO_WARNING (exp.value) = 1;
1595 break;
1596 }
1597
1598 return exp;
1599 }
1600
1601
1602 /* EXP is an expression of integer type. Apply the integer promotions
1603 to it and return the promoted value. */
1604
1605 tree
1606 perform_integral_promotions (tree exp)
1607 {
1608 tree type = TREE_TYPE (exp);
1609 enum tree_code code = TREE_CODE (type);
1610
1611 gcc_assert (INTEGRAL_TYPE_P (type));
1612
1613 /* Normally convert enums to int,
1614 but convert wide enums to something wider. */
1615 if (code == ENUMERAL_TYPE)
1616 {
1617 type = c_common_type_for_size (MAX (TYPE_PRECISION (type),
1618 TYPE_PRECISION (integer_type_node)),
1619 ((TYPE_PRECISION (type)
1620 >= TYPE_PRECISION (integer_type_node))
1621 && TYPE_UNSIGNED (type)));
1622
1623 return convert (type, exp);
1624 }
1625
1626 /* ??? This should no longer be needed now bit-fields have their
1627 proper types. */
1628 if (TREE_CODE (exp) == COMPONENT_REF
1629 && DECL_C_BIT_FIELD (TREE_OPERAND (exp, 1))
1630 /* If it's thinner than an int, promote it like a
1631 c_promoting_integer_type_p, otherwise leave it alone. */
1632 && 0 > compare_tree_int (DECL_SIZE (TREE_OPERAND (exp, 1)),
1633 TYPE_PRECISION (integer_type_node)))
1634 return convert (integer_type_node, exp);
1635
1636 if (c_promoting_integer_type_p (type))
1637 {
1638 /* Preserve unsignedness if not really getting any wider. */
1639 if (TYPE_UNSIGNED (type)
1640 && TYPE_PRECISION (type) == TYPE_PRECISION (integer_type_node))
1641 return convert (unsigned_type_node, exp);
1642
1643 return convert (integer_type_node, exp);
1644 }
1645
1646 return exp;
1647 }
1648
1649
1650 /* Perform default promotions for C data used in expressions.
1651 Enumeral types or short or char are converted to int.
1652 In addition, manifest constants symbols are replaced by their values. */
1653
1654 tree
1655 default_conversion (tree exp)
1656 {
1657 tree orig_exp;
1658 tree type = TREE_TYPE (exp);
1659 enum tree_code code = TREE_CODE (type);
1660
1661 /* Functions and arrays have been converted during parsing. */
1662 gcc_assert (code != FUNCTION_TYPE);
1663 if (code == ARRAY_TYPE)
1664 return exp;
1665
1666 /* Constants can be used directly unless they're not loadable. */
1667 if (TREE_CODE (exp) == CONST_DECL)
1668 exp = DECL_INITIAL (exp);
1669
1670 /* Replace a nonvolatile const static variable with its value unless
1671 it is an array, in which case we must be sure that taking the
1672 address of the array produces consistent results. */
1673 else if (optimize && TREE_CODE (exp) == VAR_DECL && code != ARRAY_TYPE)
1674 {
1675 exp = decl_constant_value_for_broken_optimization (exp);
1676 type = TREE_TYPE (exp);
1677 }
1678
1679 /* Strip no-op conversions. */
1680 orig_exp = exp;
1681 STRIP_TYPE_NOPS (exp);
1682
1683 if (TREE_NO_WARNING (orig_exp))
1684 TREE_NO_WARNING (exp) = 1;
1685
1686 if (INTEGRAL_TYPE_P (type))
1687 return perform_integral_promotions (exp);
1688
1689 if (code == VOID_TYPE)
1690 {
1691 error ("void value not ignored as it ought to be");
1692 return error_mark_node;
1693 }
1694 return exp;
1695 }
1696 \f
1697 /* Look up COMPONENT in a structure or union DECL.
1698
1699 If the component name is not found, returns NULL_TREE. Otherwise,
1700 the return value is a TREE_LIST, with each TREE_VALUE a FIELD_DECL
1701 stepping down the chain to the component, which is in the last
1702 TREE_VALUE of the list. Normally the list is of length one, but if
1703 the component is embedded within (nested) anonymous structures or
1704 unions, the list steps down the chain to the component. */
1705
1706 static tree
1707 lookup_field (tree decl, tree component)
1708 {
1709 tree type = TREE_TYPE (decl);
1710 tree field;
1711
1712 /* If TYPE_LANG_SPECIFIC is set, then it is a sorted array of pointers
1713 to the field elements. Use a binary search on this array to quickly
1714 find the element. Otherwise, do a linear search. TYPE_LANG_SPECIFIC
1715 will always be set for structures which have many elements. */
1716
1717 if (TYPE_LANG_SPECIFIC (type) && TYPE_LANG_SPECIFIC (type)->s)
1718 {
1719 int bot, top, half;
1720 tree *field_array = &TYPE_LANG_SPECIFIC (type)->s->elts[0];
1721
1722 field = TYPE_FIELDS (type);
1723 bot = 0;
1724 top = TYPE_LANG_SPECIFIC (type)->s->len;
1725 while (top - bot > 1)
1726 {
1727 half = (top - bot + 1) >> 1;
1728 field = field_array[bot+half];
1729
1730 if (DECL_NAME (field) == NULL_TREE)
1731 {
1732 /* Step through all anon unions in linear fashion. */
1733 while (DECL_NAME (field_array[bot]) == NULL_TREE)
1734 {
1735 field = field_array[bot++];
1736 if (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1737 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE)
1738 {
1739 tree anon = lookup_field (field, component);
1740
1741 if (anon)
1742 return tree_cons (NULL_TREE, field, anon);
1743 }
1744 }
1745
1746 /* Entire record is only anon unions. */
1747 if (bot > top)
1748 return NULL_TREE;
1749
1750 /* Restart the binary search, with new lower bound. */
1751 continue;
1752 }
1753
1754 if (DECL_NAME (field) == component)
1755 break;
1756 if (DECL_NAME (field) < component)
1757 bot += half;
1758 else
1759 top = bot + half;
1760 }
1761
1762 if (DECL_NAME (field_array[bot]) == component)
1763 field = field_array[bot];
1764 else if (DECL_NAME (field) != component)
1765 return NULL_TREE;
1766 }
1767 else
1768 {
1769 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
1770 {
1771 if (DECL_NAME (field) == NULL_TREE
1772 && (TREE_CODE (TREE_TYPE (field)) == RECORD_TYPE
1773 || TREE_CODE (TREE_TYPE (field)) == UNION_TYPE))
1774 {
1775 tree anon = lookup_field (field, component);
1776
1777 if (anon)
1778 return tree_cons (NULL_TREE, field, anon);
1779 }
1780
1781 if (DECL_NAME (field) == component)
1782 break;
1783 }
1784
1785 if (field == NULL_TREE)
1786 return NULL_TREE;
1787 }
1788
1789 return tree_cons (NULL_TREE, field, NULL_TREE);
1790 }
1791
1792 /* Make an expression to refer to the COMPONENT field of
1793 structure or union value DATUM. COMPONENT is an IDENTIFIER_NODE. */
1794
1795 tree
1796 build_component_ref (tree datum, tree component)
1797 {
1798 tree type = TREE_TYPE (datum);
1799 enum tree_code code = TREE_CODE (type);
1800 tree field = NULL;
1801 tree ref;
1802
1803 if (!objc_is_public (datum, component))
1804 return error_mark_node;
1805
1806 /* See if there is a field or component with name COMPONENT. */
1807
1808 if (code == RECORD_TYPE || code == UNION_TYPE)
1809 {
1810 if (!COMPLETE_TYPE_P (type))
1811 {
1812 c_incomplete_type_error (NULL_TREE, type);
1813 return error_mark_node;
1814 }
1815
1816 field = lookup_field (datum, component);
1817
1818 if (!field)
1819 {
1820 error ("%qT has no member named %qE", type, component);
1821 return error_mark_node;
1822 }
1823
1824 /* Chain the COMPONENT_REFs if necessary down to the FIELD.
1825 This might be better solved in future the way the C++ front
1826 end does it - by giving the anonymous entities each a
1827 separate name and type, and then have build_component_ref
1828 recursively call itself. We can't do that here. */
1829 do
1830 {
1831 tree subdatum = TREE_VALUE (field);
1832 int quals;
1833 tree subtype;
1834
1835 if (TREE_TYPE (subdatum) == error_mark_node)
1836 return error_mark_node;
1837
1838 quals = TYPE_QUALS (strip_array_types (TREE_TYPE (subdatum)));
1839 quals |= TYPE_QUALS (TREE_TYPE (datum));
1840 subtype = c_build_qualified_type (TREE_TYPE (subdatum), quals);
1841
1842 ref = build3 (COMPONENT_REF, subtype, datum, subdatum,
1843 NULL_TREE);
1844 if (TREE_READONLY (datum) || TREE_READONLY (subdatum))
1845 TREE_READONLY (ref) = 1;
1846 if (TREE_THIS_VOLATILE (datum) || TREE_THIS_VOLATILE (subdatum))
1847 TREE_THIS_VOLATILE (ref) = 1;
1848
1849 if (TREE_DEPRECATED (subdatum))
1850 warn_deprecated_use (subdatum);
1851
1852 datum = ref;
1853
1854 field = TREE_CHAIN (field);
1855 }
1856 while (field);
1857
1858 return ref;
1859 }
1860 else if (code != ERROR_MARK)
1861 error ("request for member %qE in something not a structure or union",
1862 component);
1863
1864 return error_mark_node;
1865 }
1866 \f
1867 /* Given an expression PTR for a pointer, return an expression
1868 for the value pointed to.
1869 ERRORSTRING is the name of the operator to appear in error messages. */
1870
1871 tree
1872 build_indirect_ref (tree ptr, const char *errorstring)
1873 {
1874 tree pointer = default_conversion (ptr);
1875 tree type = TREE_TYPE (pointer);
1876
1877 if (TREE_CODE (type) == POINTER_TYPE)
1878 {
1879 if (TREE_CODE (pointer) == ADDR_EXPR
1880 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1881 == TREE_TYPE (type)))
1882 return TREE_OPERAND (pointer, 0);
1883 else
1884 {
1885 tree t = TREE_TYPE (type);
1886 tree ref;
1887
1888 ref = build1 (INDIRECT_REF, t, pointer);
1889
1890 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1891 {
1892 error ("dereferencing pointer to incomplete type");
1893 return error_mark_node;
1894 }
1895 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1896 warning (0, "dereferencing %<void *%> pointer");
1897
1898 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1899 so that we get the proper error message if the result is used
1900 to assign to. Also, &* is supposed to be a no-op.
1901 And ANSI C seems to specify that the type of the result
1902 should be the const type. */
1903 /* A de-reference of a pointer to const is not a const. It is valid
1904 to change it via some other pointer. */
1905 TREE_READONLY (ref) = TYPE_READONLY (t);
1906 TREE_SIDE_EFFECTS (ref)
1907 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
1908 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1909 return ref;
1910 }
1911 }
1912 else if (TREE_CODE (pointer) != ERROR_MARK)
1913 error ("invalid type argument of %qs", errorstring);
1914 return error_mark_node;
1915 }
1916
1917 /* This handles expressions of the form "a[i]", which denotes
1918 an array reference.
1919
1920 This is logically equivalent in C to *(a+i), but we may do it differently.
1921 If A is a variable or a member, we generate a primitive ARRAY_REF.
1922 This avoids forcing the array out of registers, and can work on
1923 arrays that are not lvalues (for example, members of structures returned
1924 by functions). */
1925
1926 tree
1927 build_array_ref (tree array, tree index)
1928 {
1929 bool swapped = false;
1930 if (TREE_TYPE (array) == error_mark_node
1931 || TREE_TYPE (index) == error_mark_node)
1932 return error_mark_node;
1933
1934 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE
1935 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE)
1936 {
1937 tree temp;
1938 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE
1939 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE)
1940 {
1941 error ("subscripted value is neither array nor pointer");
1942 return error_mark_node;
1943 }
1944 temp = array;
1945 array = index;
1946 index = temp;
1947 swapped = true;
1948 }
1949
1950 if (!INTEGRAL_TYPE_P (TREE_TYPE (index)))
1951 {
1952 error ("array subscript is not an integer");
1953 return error_mark_node;
1954 }
1955
1956 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE)
1957 {
1958 error ("subscripted value is pointer to function");
1959 return error_mark_node;
1960 }
1961
1962 /* ??? Existing practice has been to warn only when the char
1963 index is syntactically the index, not for char[array]. */
1964 if (!swapped)
1965 warn_array_subscript_with_type_char (index);
1966
1967 /* Apply default promotions *after* noticing character types. */
1968 index = default_conversion (index);
1969
1970 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE);
1971
1972 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
1973 {
1974 tree rval, type;
1975
1976 /* An array that is indexed by a non-constant
1977 cannot be stored in a register; we must be able to do
1978 address arithmetic on its address.
1979 Likewise an array of elements of variable size. */
1980 if (TREE_CODE (index) != INTEGER_CST
1981 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
1982 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
1983 {
1984 if (!c_mark_addressable (array))
1985 return error_mark_node;
1986 }
1987 /* An array that is indexed by a constant value which is not within
1988 the array bounds cannot be stored in a register either; because we
1989 would get a crash in store_bit_field/extract_bit_field when trying
1990 to access a non-existent part of the register. */
1991 if (TREE_CODE (index) == INTEGER_CST
1992 && TYPE_DOMAIN (TREE_TYPE (array))
1993 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
1994 {
1995 if (!c_mark_addressable (array))
1996 return error_mark_node;
1997 }
1998
1999 if (pedantic)
2000 {
2001 tree foo = array;
2002 while (TREE_CODE (foo) == COMPONENT_REF)
2003 foo = TREE_OPERAND (foo, 0);
2004 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
2005 pedwarn ("ISO C forbids subscripting %<register%> array");
2006 else if (!flag_isoc99 && !lvalue_p (foo))
2007 pedwarn ("ISO C90 forbids subscripting non-lvalue array");
2008 }
2009
2010 type = TREE_TYPE (TREE_TYPE (array));
2011 if (TREE_CODE (type) != ARRAY_TYPE)
2012 type = TYPE_MAIN_VARIANT (type);
2013 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE);
2014 /* Array ref is const/volatile if the array elements are
2015 or if the array is. */
2016 TREE_READONLY (rval)
2017 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
2018 | TREE_READONLY (array));
2019 TREE_SIDE_EFFECTS (rval)
2020 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2021 | TREE_SIDE_EFFECTS (array));
2022 TREE_THIS_VOLATILE (rval)
2023 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2024 /* This was added by rms on 16 Nov 91.
2025 It fixes vol struct foo *a; a->elts[1]
2026 in an inline function.
2027 Hope it doesn't break something else. */
2028 | TREE_THIS_VOLATILE (array));
2029 return require_complete_type (fold (rval));
2030 }
2031 else
2032 {
2033 tree ar = default_conversion (array);
2034
2035 if (ar == error_mark_node)
2036 return ar;
2037
2038 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE);
2039 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE);
2040
2041 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0),
2042 "array indexing");
2043 }
2044 }
2045 \f
2046 /* Build an external reference to identifier ID. FUN indicates
2047 whether this will be used for a function call. LOC is the source
2048 location of the identifier. */
2049 tree
2050 build_external_ref (tree id, int fun, location_t loc)
2051 {
2052 tree ref;
2053 tree decl = lookup_name (id);
2054
2055 /* In Objective-C, an instance variable (ivar) may be preferred to
2056 whatever lookup_name() found. */
2057 decl = objc_lookup_ivar (decl, id);
2058
2059 if (decl && decl != error_mark_node)
2060 ref = decl;
2061 else if (fun)
2062 /* Implicit function declaration. */
2063 ref = implicitly_declare (id);
2064 else if (decl == error_mark_node)
2065 /* Don't complain about something that's already been
2066 complained about. */
2067 return error_mark_node;
2068 else
2069 {
2070 undeclared_variable (id, loc);
2071 return error_mark_node;
2072 }
2073
2074 if (TREE_TYPE (ref) == error_mark_node)
2075 return error_mark_node;
2076
2077 if (TREE_DEPRECATED (ref))
2078 warn_deprecated_use (ref);
2079
2080 if (!skip_evaluation)
2081 assemble_external (ref);
2082 TREE_USED (ref) = 1;
2083
2084 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof)
2085 {
2086 if (!in_sizeof && !in_typeof)
2087 C_DECL_USED (ref) = 1;
2088 else if (DECL_INITIAL (ref) == 0
2089 && DECL_EXTERNAL (ref)
2090 && !TREE_PUBLIC (ref))
2091 record_maybe_used_decl (ref);
2092 }
2093
2094 if (TREE_CODE (ref) == CONST_DECL)
2095 {
2096 used_types_insert (TREE_TYPE (ref));
2097 ref = DECL_INITIAL (ref);
2098 TREE_CONSTANT (ref) = 1;
2099 TREE_INVARIANT (ref) = 1;
2100 }
2101 else if (current_function_decl != 0
2102 && !DECL_FILE_SCOPE_P (current_function_decl)
2103 && (TREE_CODE (ref) == VAR_DECL
2104 || TREE_CODE (ref) == PARM_DECL
2105 || TREE_CODE (ref) == FUNCTION_DECL))
2106 {
2107 tree context = decl_function_context (ref);
2108
2109 if (context != 0 && context != current_function_decl)
2110 DECL_NONLOCAL (ref) = 1;
2111 }
2112 /* C99 6.7.4p3: An inline definition of a function with external
2113 linkage ... shall not contain a reference to an identifier with
2114 internal linkage. */
2115 else if (current_function_decl != 0
2116 && DECL_DECLARED_INLINE_P (current_function_decl)
2117 && DECL_EXTERNAL (current_function_decl)
2118 && VAR_OR_FUNCTION_DECL_P (ref)
2119 && (TREE_CODE (ref) != VAR_DECL || TREE_STATIC (ref))
2120 && ! TREE_PUBLIC (ref))
2121 pedwarn ("%H%qD is static but used in inline function %qD "
2122 "which is not static", &loc, ref, current_function_decl);
2123
2124 return ref;
2125 }
2126
2127 /* Record details of decls possibly used inside sizeof or typeof. */
2128 struct maybe_used_decl
2129 {
2130 /* The decl. */
2131 tree decl;
2132 /* The level seen at (in_sizeof + in_typeof). */
2133 int level;
2134 /* The next one at this level or above, or NULL. */
2135 struct maybe_used_decl *next;
2136 };
2137
2138 static struct maybe_used_decl *maybe_used_decls;
2139
2140 /* Record that DECL, an undefined static function reference seen
2141 inside sizeof or typeof, might be used if the operand of sizeof is
2142 a VLA type or the operand of typeof is a variably modified
2143 type. */
2144
2145 static void
2146 record_maybe_used_decl (tree decl)
2147 {
2148 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl);
2149 t->decl = decl;
2150 t->level = in_sizeof + in_typeof;
2151 t->next = maybe_used_decls;
2152 maybe_used_decls = t;
2153 }
2154
2155 /* Pop the stack of decls possibly used inside sizeof or typeof. If
2156 USED is false, just discard them. If it is true, mark them used
2157 (if no longer inside sizeof or typeof) or move them to the next
2158 level up (if still inside sizeof or typeof). */
2159
2160 void
2161 pop_maybe_used (bool used)
2162 {
2163 struct maybe_used_decl *p = maybe_used_decls;
2164 int cur_level = in_sizeof + in_typeof;
2165 while (p && p->level > cur_level)
2166 {
2167 if (used)
2168 {
2169 if (cur_level == 0)
2170 C_DECL_USED (p->decl) = 1;
2171 else
2172 p->level = cur_level;
2173 }
2174 p = p->next;
2175 }
2176 if (!used || cur_level == 0)
2177 maybe_used_decls = p;
2178 }
2179
2180 /* Return the result of sizeof applied to EXPR. */
2181
2182 struct c_expr
2183 c_expr_sizeof_expr (struct c_expr expr)
2184 {
2185 struct c_expr ret;
2186 if (expr.value == error_mark_node)
2187 {
2188 ret.value = error_mark_node;
2189 ret.original_code = ERROR_MARK;
2190 pop_maybe_used (false);
2191 }
2192 else
2193 {
2194 ret.value = c_sizeof (TREE_TYPE (expr.value));
2195 ret.original_code = ERROR_MARK;
2196 if (c_vla_type_p (TREE_TYPE (expr.value)))
2197 {
2198 /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */
2199 ret.value = build2 (COMPOUND_EXPR, TREE_TYPE (ret.value), expr.value, ret.value);
2200 }
2201 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value)));
2202 }
2203 return ret;
2204 }
2205
2206 /* Return the result of sizeof applied to T, a structure for the type
2207 name passed to sizeof (rather than the type itself). */
2208
2209 struct c_expr
2210 c_expr_sizeof_type (struct c_type_name *t)
2211 {
2212 tree type;
2213 struct c_expr ret;
2214 type = groktypename (t);
2215 ret.value = c_sizeof (type);
2216 ret.original_code = ERROR_MARK;
2217 pop_maybe_used (type != error_mark_node
2218 ? C_TYPE_VARIABLE_SIZE (type) : false);
2219 return ret;
2220 }
2221
2222 /* Build a function call to function FUNCTION with parameters PARAMS.
2223 PARAMS is a list--a chain of TREE_LIST nodes--in which the
2224 TREE_VALUE of each node is a parameter-expression.
2225 FUNCTION's data type may be a function type or a pointer-to-function. */
2226
2227 tree
2228 build_function_call (tree function, tree params)
2229 {
2230 tree fntype, fundecl = 0;
2231 tree coerced_params;
2232 tree name = NULL_TREE, result;
2233 tree tem;
2234
2235 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2236 STRIP_TYPE_NOPS (function);
2237
2238 /* Convert anything with function type to a pointer-to-function. */
2239 if (TREE_CODE (function) == FUNCTION_DECL)
2240 {
2241 /* Implement type-directed function overloading for builtins.
2242 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin
2243 handle all the type checking. The result is a complete expression
2244 that implements this function call. */
2245 tem = resolve_overloaded_builtin (function, params);
2246 if (tem)
2247 return tem;
2248
2249 name = DECL_NAME (function);
2250 fundecl = function;
2251 }
2252 if (TREE_CODE (TREE_TYPE (function)) == FUNCTION_TYPE)
2253 function = function_to_pointer_conversion (function);
2254
2255 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2256 expressions, like those used for ObjC messenger dispatches. */
2257 function = objc_rewrite_function_call (function, params);
2258
2259 fntype = TREE_TYPE (function);
2260
2261 if (TREE_CODE (fntype) == ERROR_MARK)
2262 return error_mark_node;
2263
2264 if (!(TREE_CODE (fntype) == POINTER_TYPE
2265 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
2266 {
2267 error ("called object %qE is not a function", function);
2268 return error_mark_node;
2269 }
2270
2271 if (fundecl && TREE_THIS_VOLATILE (fundecl))
2272 current_function_returns_abnormally = 1;
2273
2274 /* fntype now gets the type of function pointed to. */
2275 fntype = TREE_TYPE (fntype);
2276
2277 /* Check that the function is called through a compatible prototype.
2278 If it is not, replace the call by a trap, wrapped up in a compound
2279 expression if necessary. This has the nice side-effect to prevent
2280 the tree-inliner from generating invalid assignment trees which may
2281 blow up in the RTL expander later. */
2282 if ((TREE_CODE (function) == NOP_EXPR
2283 || TREE_CODE (function) == CONVERT_EXPR)
2284 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
2285 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
2286 && !comptypes (fntype, TREE_TYPE (tem)))
2287 {
2288 tree return_type = TREE_TYPE (fntype);
2289 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP],
2290 NULL_TREE);
2291
2292 /* This situation leads to run-time undefined behavior. We can't,
2293 therefore, simply error unless we can prove that all possible
2294 executions of the program must execute the code. */
2295 warning (0, "function called through a non-compatible type");
2296
2297 /* We can, however, treat "undefined" any way we please.
2298 Call abort to encourage the user to fix the program. */
2299 inform ("if this code is reached, the program will abort");
2300
2301 if (VOID_TYPE_P (return_type))
2302 return trap;
2303 else
2304 {
2305 tree rhs;
2306
2307 if (AGGREGATE_TYPE_P (return_type))
2308 rhs = build_compound_literal (return_type,
2309 build_constructor (return_type, 0));
2310 else
2311 rhs = fold_convert (return_type, integer_zero_node);
2312
2313 return build2 (COMPOUND_EXPR, return_type, trap, rhs);
2314 }
2315 }
2316
2317 /* Convert the parameters to the types declared in the
2318 function prototype, or apply default promotions. */
2319
2320 coerced_params
2321 = convert_arguments (TYPE_ARG_TYPES (fntype), params, function, fundecl);
2322
2323 if (coerced_params == error_mark_node)
2324 return error_mark_node;
2325
2326 /* Check that the arguments to the function are valid. */
2327
2328 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params,
2329 TYPE_ARG_TYPES (fntype));
2330
2331 if (require_constant_value)
2332 {
2333 result = fold_build3_initializer (CALL_EXPR, TREE_TYPE (fntype),
2334 function, coerced_params, NULL_TREE);
2335
2336 if (TREE_CONSTANT (result)
2337 && (name == NULL_TREE
2338 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0))
2339 pedwarn_init ("initializer element is not constant");
2340 }
2341 else
2342 result = fold_build3 (CALL_EXPR, TREE_TYPE (fntype),
2343 function, coerced_params, NULL_TREE);
2344
2345 if (VOID_TYPE_P (TREE_TYPE (result)))
2346 return result;
2347 return require_complete_type (result);
2348 }
2349 \f
2350 /* Convert the argument expressions in the list VALUES
2351 to the types in the list TYPELIST. The result is a list of converted
2352 argument expressions, unless there are too few arguments in which
2353 case it is error_mark_node.
2354
2355 If TYPELIST is exhausted, or when an element has NULL as its type,
2356 perform the default conversions.
2357
2358 PARMLIST is the chain of parm decls for the function being called.
2359 It may be 0, if that info is not available.
2360 It is used only for generating error messages.
2361
2362 FUNCTION is a tree for the called function. It is used only for
2363 error messages, where it is formatted with %qE.
2364
2365 This is also where warnings about wrong number of args are generated.
2366
2367 Both VALUES and the returned value are chains of TREE_LIST nodes
2368 with the elements of the list in the TREE_VALUE slots of those nodes. */
2369
2370 static tree
2371 convert_arguments (tree typelist, tree values, tree function, tree fundecl)
2372 {
2373 tree typetail, valtail;
2374 tree result = NULL;
2375 int parmnum;
2376 tree selector;
2377
2378 /* Change pointer to function to the function itself for
2379 diagnostics. */
2380 if (TREE_CODE (function) == ADDR_EXPR
2381 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
2382 function = TREE_OPERAND (function, 0);
2383
2384 /* Handle an ObjC selector specially for diagnostics. */
2385 selector = objc_message_selector ();
2386
2387 /* Scan the given expressions and types, producing individual
2388 converted arguments and pushing them on RESULT in reverse order. */
2389
2390 for (valtail = values, typetail = typelist, parmnum = 0;
2391 valtail;
2392 valtail = TREE_CHAIN (valtail), parmnum++)
2393 {
2394 tree type = typetail ? TREE_VALUE (typetail) : 0;
2395 tree val = TREE_VALUE (valtail);
2396 tree rname = function;
2397 int argnum = parmnum + 1;
2398 const char *invalid_func_diag;
2399
2400 if (type == void_type_node)
2401 {
2402 error ("too many arguments to function %qE", function);
2403 break;
2404 }
2405
2406 if (selector && argnum > 2)
2407 {
2408 rname = selector;
2409 argnum -= 2;
2410 }
2411
2412 STRIP_TYPE_NOPS (val);
2413
2414 val = require_complete_type (val);
2415
2416 if (type != 0)
2417 {
2418 /* Formal parm type is specified by a function prototype. */
2419 tree parmval;
2420
2421 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
2422 {
2423 error ("type of formal parameter %d is incomplete", parmnum + 1);
2424 parmval = val;
2425 }
2426 else
2427 {
2428 /* Optionally warn about conversions that
2429 differ from the default conversions. */
2430 if (warn_traditional_conversion || warn_traditional)
2431 {
2432 unsigned int formal_prec = TYPE_PRECISION (type);
2433
2434 if (INTEGRAL_TYPE_P (type)
2435 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2436 warning (0, "passing argument %d of %qE as integer "
2437 "rather than floating due to prototype",
2438 argnum, rname);
2439 if (INTEGRAL_TYPE_P (type)
2440 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2441 warning (0, "passing argument %d of %qE as integer "
2442 "rather than complex due to prototype",
2443 argnum, rname);
2444 else if (TREE_CODE (type) == COMPLEX_TYPE
2445 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2446 warning (0, "passing argument %d of %qE as complex "
2447 "rather than floating due to prototype",
2448 argnum, rname);
2449 else if (TREE_CODE (type) == REAL_TYPE
2450 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2451 warning (0, "passing argument %d of %qE as floating "
2452 "rather than integer due to prototype",
2453 argnum, rname);
2454 else if (TREE_CODE (type) == COMPLEX_TYPE
2455 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2456 warning (0, "passing argument %d of %qE as complex "
2457 "rather than integer due to prototype",
2458 argnum, rname);
2459 else if (TREE_CODE (type) == REAL_TYPE
2460 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2461 warning (0, "passing argument %d of %qE as floating "
2462 "rather than complex due to prototype",
2463 argnum, rname);
2464 /* ??? At some point, messages should be written about
2465 conversions between complex types, but that's too messy
2466 to do now. */
2467 else if (TREE_CODE (type) == REAL_TYPE
2468 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2469 {
2470 /* Warn if any argument is passed as `float',
2471 since without a prototype it would be `double'. */
2472 if (formal_prec == TYPE_PRECISION (float_type_node)
2473 && type != dfloat32_type_node)
2474 warning (0, "passing argument %d of %qE as %<float%> "
2475 "rather than %<double%> due to prototype",
2476 argnum, rname);
2477
2478 /* Warn if mismatch between argument and prototype
2479 for decimal float types. Warn of conversions with
2480 binary float types and of precision narrowing due to
2481 prototype. */
2482 else if (type != TREE_TYPE (val)
2483 && (type == dfloat32_type_node
2484 || type == dfloat64_type_node
2485 || type == dfloat128_type_node
2486 || TREE_TYPE (val) == dfloat32_type_node
2487 || TREE_TYPE (val) == dfloat64_type_node
2488 || TREE_TYPE (val) == dfloat128_type_node)
2489 && (formal_prec
2490 <= TYPE_PRECISION (TREE_TYPE (val))
2491 || (type == dfloat128_type_node
2492 && (TREE_TYPE (val)
2493 != dfloat64_type_node
2494 && (TREE_TYPE (val)
2495 != dfloat32_type_node)))
2496 || (type == dfloat64_type_node
2497 && (TREE_TYPE (val)
2498 != dfloat32_type_node))))
2499 warning (0, "passing argument %d of %qE as %qT "
2500 "rather than %qT due to prototype",
2501 argnum, rname, type, TREE_TYPE (val));
2502
2503 }
2504 /* Detect integer changing in width or signedness.
2505 These warnings are only activated with
2506 -Wtraditional-conversion, not with -Wtraditional. */
2507 else if (warn_traditional_conversion && INTEGRAL_TYPE_P (type)
2508 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2509 {
2510 tree would_have_been = default_conversion (val);
2511 tree type1 = TREE_TYPE (would_have_been);
2512
2513 if (TREE_CODE (type) == ENUMERAL_TYPE
2514 && (TYPE_MAIN_VARIANT (type)
2515 == TYPE_MAIN_VARIANT (TREE_TYPE (val))))
2516 /* No warning if function asks for enum
2517 and the actual arg is that enum type. */
2518 ;
2519 else if (formal_prec != TYPE_PRECISION (type1))
2520 warning (OPT_Wtraditional_conversion, "passing argument %d of %qE "
2521 "with different width due to prototype",
2522 argnum, rname);
2523 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2524 ;
2525 /* Don't complain if the formal parameter type
2526 is an enum, because we can't tell now whether
2527 the value was an enum--even the same enum. */
2528 else if (TREE_CODE (type) == ENUMERAL_TYPE)
2529 ;
2530 else if (TREE_CODE (val) == INTEGER_CST
2531 && int_fits_type_p (val, type))
2532 /* Change in signedness doesn't matter
2533 if a constant value is unaffected. */
2534 ;
2535 /* If the value is extended from a narrower
2536 unsigned type, it doesn't matter whether we
2537 pass it as signed or unsigned; the value
2538 certainly is the same either way. */
2539 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
2540 && TYPE_UNSIGNED (TREE_TYPE (val)))
2541 ;
2542 else if (TYPE_UNSIGNED (type))
2543 warning (OPT_Wtraditional_conversion, "passing argument %d of %qE "
2544 "as unsigned due to prototype",
2545 argnum, rname);
2546 else
2547 warning (OPT_Wtraditional_conversion, "passing argument %d of %qE "
2548 "as signed due to prototype", argnum, rname);
2549 }
2550 }
2551
2552 parmval = convert_for_assignment (type, val, ic_argpass,
2553 fundecl, function,
2554 parmnum + 1);
2555
2556 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
2557 && INTEGRAL_TYPE_P (type)
2558 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
2559 parmval = default_conversion (parmval);
2560 }
2561 result = tree_cons (NULL_TREE, parmval, result);
2562 }
2563 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
2564 && (TYPE_PRECISION (TREE_TYPE (val))
2565 < TYPE_PRECISION (double_type_node))
2566 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (val))))
2567 /* Convert `float' to `double'. */
2568 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
2569 else if ((invalid_func_diag =
2570 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val)))
2571 {
2572 error (invalid_func_diag);
2573 return error_mark_node;
2574 }
2575 else
2576 /* Convert `short' and `char' to full-size `int'. */
2577 result = tree_cons (NULL_TREE, default_conversion (val), result);
2578
2579 if (typetail)
2580 typetail = TREE_CHAIN (typetail);
2581 }
2582
2583 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
2584 {
2585 error ("too few arguments to function %qE", function);
2586 return error_mark_node;
2587 }
2588
2589 return nreverse (result);
2590 }
2591 \f
2592 /* This is the entry point used by the parser to build unary operators
2593 in the input. CODE, a tree_code, specifies the unary operator, and
2594 ARG is the operand. For unary plus, the C parser currently uses
2595 CONVERT_EXPR for code. */
2596
2597 struct c_expr
2598 parser_build_unary_op (enum tree_code code, struct c_expr arg)
2599 {
2600 struct c_expr result;
2601
2602 result.original_code = ERROR_MARK;
2603 result.value = build_unary_op (code, arg.value, 0);
2604 overflow_warning (result.value);
2605 return result;
2606 }
2607
2608 /* This is the entry point used by the parser to build binary operators
2609 in the input. CODE, a tree_code, specifies the binary operator, and
2610 ARG1 and ARG2 are the operands. In addition to constructing the
2611 expression, we check for operands that were written with other binary
2612 operators in a way that is likely to confuse the user. */
2613
2614 struct c_expr
2615 parser_build_binary_op (enum tree_code code, struct c_expr arg1,
2616 struct c_expr arg2)
2617 {
2618 struct c_expr result;
2619
2620 enum tree_code code1 = arg1.original_code;
2621 enum tree_code code2 = arg2.original_code;
2622
2623 result.value = build_binary_op (code, arg1.value, arg2.value, 1);
2624 result.original_code = code;
2625
2626 if (TREE_CODE (result.value) == ERROR_MARK)
2627 return result;
2628
2629 /* Check for cases such as x+y<<z which users are likely
2630 to misinterpret. */
2631 if (warn_parentheses)
2632 warn_about_parentheses (code, code1, code2);
2633
2634 /* Warn about comparisons against string literals, with the exception
2635 of testing for equality or inequality of a string literal with NULL. */
2636 if (code == EQ_EXPR || code == NE_EXPR)
2637 {
2638 if ((code1 == STRING_CST && !integer_zerop (arg2.value))
2639 || (code2 == STRING_CST && !integer_zerop (arg1.value)))
2640 warning (OPT_Wstring_literal_comparison,
2641 "comparison with string literal");
2642 }
2643 else if (TREE_CODE_CLASS (code) == tcc_comparison
2644 && (code1 == STRING_CST || code2 == STRING_CST))
2645 warning (OPT_Wstring_literal_comparison,
2646 "comparison with string literal");
2647
2648 overflow_warning (result.value);
2649
2650 return result;
2651 }
2652 \f
2653 /* Return a tree for the difference of pointers OP0 and OP1.
2654 The resulting tree has type int. */
2655
2656 static tree
2657 pointer_diff (tree op0, tree op1)
2658 {
2659 tree restype = ptrdiff_type_node;
2660
2661 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2662 tree con0, con1, lit0, lit1;
2663 tree orig_op1 = op1;
2664
2665 if (pedantic || warn_pointer_arith)
2666 {
2667 if (TREE_CODE (target_type) == VOID_TYPE)
2668 pedwarn ("pointer of type %<void *%> used in subtraction");
2669 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2670 pedwarn ("pointer to a function used in subtraction");
2671 }
2672
2673 /* If the conversion to ptrdiff_type does anything like widening or
2674 converting a partial to an integral mode, we get a convert_expression
2675 that is in the way to do any simplifications.
2676 (fold-const.c doesn't know that the extra bits won't be needed.
2677 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2678 different mode in place.)
2679 So first try to find a common term here 'by hand'; we want to cover
2680 at least the cases that occur in legal static initializers. */
2681 if ((TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == CONVERT_EXPR)
2682 && (TYPE_PRECISION (TREE_TYPE (op0))
2683 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
2684 con0 = TREE_OPERAND (op0, 0);
2685 else
2686 con0 = op0;
2687 if ((TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == CONVERT_EXPR)
2688 && (TYPE_PRECISION (TREE_TYPE (op1))
2689 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))))
2690 con1 = TREE_OPERAND (op1, 0);
2691 else
2692 con1 = op1;
2693
2694 if (TREE_CODE (con0) == PLUS_EXPR)
2695 {
2696 lit0 = TREE_OPERAND (con0, 1);
2697 con0 = TREE_OPERAND (con0, 0);
2698 }
2699 else
2700 lit0 = integer_zero_node;
2701
2702 if (TREE_CODE (con1) == PLUS_EXPR)
2703 {
2704 lit1 = TREE_OPERAND (con1, 1);
2705 con1 = TREE_OPERAND (con1, 0);
2706 }
2707 else
2708 lit1 = integer_zero_node;
2709
2710 if (operand_equal_p (con0, con1, 0))
2711 {
2712 op0 = lit0;
2713 op1 = lit1;
2714 }
2715
2716
2717 /* First do the subtraction as integers;
2718 then drop through to build the divide operator.
2719 Do not do default conversions on the minus operator
2720 in case restype is a short type. */
2721
2722 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2723 convert (restype, op1), 0);
2724 /* This generates an error if op1 is pointer to incomplete type. */
2725 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
2726 error ("arithmetic on pointer to an incomplete type");
2727
2728 /* This generates an error if op0 is pointer to incomplete type. */
2729 op1 = c_size_in_bytes (target_type);
2730
2731 /* Divide by the size, in easiest possible way. */
2732 return fold_build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2733 }
2734 \f
2735 /* Construct and perhaps optimize a tree representation
2736 for a unary operation. CODE, a tree_code, specifies the operation
2737 and XARG is the operand.
2738 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2739 the default promotions (such as from short to int).
2740 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2741 allows non-lvalues; this is only used to handle conversion of non-lvalue
2742 arrays to pointers in C99. */
2743
2744 tree
2745 build_unary_op (enum tree_code code, tree xarg, int flag)
2746 {
2747 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2748 tree arg = xarg;
2749 tree argtype = 0;
2750 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2751 tree val;
2752 int noconvert = flag;
2753 const char *invalid_op_diag;
2754
2755 if (typecode == ERROR_MARK)
2756 return error_mark_node;
2757 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2758 typecode = INTEGER_TYPE;
2759
2760 if ((invalid_op_diag
2761 = targetm.invalid_unary_op (code, TREE_TYPE (xarg))))
2762 {
2763 error (invalid_op_diag);
2764 return error_mark_node;
2765 }
2766
2767 switch (code)
2768 {
2769 case CONVERT_EXPR:
2770 /* This is used for unary plus, because a CONVERT_EXPR
2771 is enough to prevent anybody from looking inside for
2772 associativity, but won't generate any code. */
2773 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2774 || typecode == COMPLEX_TYPE
2775 || typecode == VECTOR_TYPE))
2776 {
2777 error ("wrong type argument to unary plus");
2778 return error_mark_node;
2779 }
2780 else if (!noconvert)
2781 arg = default_conversion (arg);
2782 arg = non_lvalue (arg);
2783 break;
2784
2785 case NEGATE_EXPR:
2786 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2787 || typecode == COMPLEX_TYPE
2788 || typecode == VECTOR_TYPE))
2789 {
2790 error ("wrong type argument to unary minus");
2791 return error_mark_node;
2792 }
2793 else if (!noconvert)
2794 arg = default_conversion (arg);
2795 break;
2796
2797 case BIT_NOT_EXPR:
2798 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE)
2799 {
2800 if (!noconvert)
2801 arg = default_conversion (arg);
2802 }
2803 else if (typecode == COMPLEX_TYPE)
2804 {
2805 code = CONJ_EXPR;
2806 if (pedantic)
2807 pedwarn ("ISO C does not support %<~%> for complex conjugation");
2808 if (!noconvert)
2809 arg = default_conversion (arg);
2810 }
2811 else
2812 {
2813 error ("wrong type argument to bit-complement");
2814 return error_mark_node;
2815 }
2816 break;
2817
2818 case ABS_EXPR:
2819 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
2820 {
2821 error ("wrong type argument to abs");
2822 return error_mark_node;
2823 }
2824 else if (!noconvert)
2825 arg = default_conversion (arg);
2826 break;
2827
2828 case CONJ_EXPR:
2829 /* Conjugating a real value is a no-op, but allow it anyway. */
2830 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2831 || typecode == COMPLEX_TYPE))
2832 {
2833 error ("wrong type argument to conjugation");
2834 return error_mark_node;
2835 }
2836 else if (!noconvert)
2837 arg = default_conversion (arg);
2838 break;
2839
2840 case TRUTH_NOT_EXPR:
2841 if (typecode != INTEGER_TYPE
2842 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2843 && typecode != COMPLEX_TYPE)
2844 {
2845 error ("wrong type argument to unary exclamation mark");
2846 return error_mark_node;
2847 }
2848 arg = c_objc_common_truthvalue_conversion (arg);
2849 return invert_truthvalue (arg);
2850
2851 case REALPART_EXPR:
2852 if (TREE_CODE (arg) == COMPLEX_CST)
2853 return TREE_REALPART (arg);
2854 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2855 return fold_build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
2856 else
2857 return arg;
2858
2859 case IMAGPART_EXPR:
2860 if (TREE_CODE (arg) == COMPLEX_CST)
2861 return TREE_IMAGPART (arg);
2862 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2863 return fold_build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
2864 else
2865 return convert (TREE_TYPE (arg), integer_zero_node);
2866
2867 case PREINCREMENT_EXPR:
2868 case POSTINCREMENT_EXPR:
2869 case PREDECREMENT_EXPR:
2870 case POSTDECREMENT_EXPR:
2871
2872 /* Increment or decrement the real part of the value,
2873 and don't change the imaginary part. */
2874 if (typecode == COMPLEX_TYPE)
2875 {
2876 tree real, imag;
2877
2878 if (pedantic)
2879 pedwarn ("ISO C does not support %<++%> and %<--%>"
2880 " on complex types");
2881
2882 arg = stabilize_reference (arg);
2883 real = build_unary_op (REALPART_EXPR, arg, 1);
2884 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2885 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
2886 build_unary_op (code, real, 1), imag);
2887 }
2888
2889 /* Report invalid types. */
2890
2891 if (typecode != POINTER_TYPE
2892 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2893 {
2894 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2895 error ("wrong type argument to increment");
2896 else
2897 error ("wrong type argument to decrement");
2898
2899 return error_mark_node;
2900 }
2901
2902 {
2903 tree inc;
2904 tree result_type = TREE_TYPE (arg);
2905
2906 arg = get_unwidened (arg, 0);
2907 argtype = TREE_TYPE (arg);
2908
2909 /* Compute the increment. */
2910
2911 if (typecode == POINTER_TYPE)
2912 {
2913 /* If pointer target is an undefined struct,
2914 we just cannot know how to do the arithmetic. */
2915 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2916 {
2917 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2918 error ("increment of pointer to unknown structure");
2919 else
2920 error ("decrement of pointer to unknown structure");
2921 }
2922 else if ((pedantic || warn_pointer_arith)
2923 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2924 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2925 {
2926 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2927 pedwarn ("wrong type argument to increment");
2928 else
2929 pedwarn ("wrong type argument to decrement");
2930 }
2931
2932 inc = c_size_in_bytes (TREE_TYPE (result_type));
2933 }
2934 else
2935 inc = integer_one_node;
2936
2937 inc = convert (argtype, inc);
2938
2939 /* Complain about anything else that is not a true lvalue. */
2940 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2941 || code == POSTINCREMENT_EXPR)
2942 ? lv_increment
2943 : lv_decrement)))
2944 return error_mark_node;
2945
2946 /* Report a read-only lvalue. */
2947 if (TREE_READONLY (arg))
2948 {
2949 readonly_error (arg,
2950 ((code == PREINCREMENT_EXPR
2951 || code == POSTINCREMENT_EXPR)
2952 ? lv_increment : lv_decrement));
2953 return error_mark_node;
2954 }
2955
2956 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
2957 val = boolean_increment (code, arg);
2958 else
2959 val = build2 (code, TREE_TYPE (arg), arg, inc);
2960 TREE_SIDE_EFFECTS (val) = 1;
2961 val = convert (result_type, val);
2962 if (TREE_CODE (val) != code)
2963 TREE_NO_WARNING (val) = 1;
2964 return val;
2965 }
2966
2967 case ADDR_EXPR:
2968 /* Note that this operation never does default_conversion. */
2969
2970 /* Let &* cancel out to simplify resulting code. */
2971 if (TREE_CODE (arg) == INDIRECT_REF)
2972 {
2973 /* Don't let this be an lvalue. */
2974 if (lvalue_p (TREE_OPERAND (arg, 0)))
2975 return non_lvalue (TREE_OPERAND (arg, 0));
2976 return TREE_OPERAND (arg, 0);
2977 }
2978
2979 /* For &x[y], return x+y */
2980 if (TREE_CODE (arg) == ARRAY_REF)
2981 {
2982 tree op0 = TREE_OPERAND (arg, 0);
2983 if (!c_mark_addressable (op0))
2984 return error_mark_node;
2985 return build_binary_op (PLUS_EXPR,
2986 (TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE
2987 ? array_to_pointer_conversion (op0)
2988 : op0),
2989 TREE_OPERAND (arg, 1), 1);
2990 }
2991
2992 /* Anything not already handled and not a true memory reference
2993 or a non-lvalue array is an error. */
2994 else if (typecode != FUNCTION_TYPE && !flag
2995 && !lvalue_or_else (arg, lv_addressof))
2996 return error_mark_node;
2997
2998 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
2999 argtype = TREE_TYPE (arg);
3000
3001 /* If the lvalue is const or volatile, merge that into the type
3002 to which the address will point. Note that you can't get a
3003 restricted pointer by taking the address of something, so we
3004 only have to deal with `const' and `volatile' here. */
3005 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
3006 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
3007 argtype = c_build_type_variant (argtype,
3008 TREE_READONLY (arg),
3009 TREE_THIS_VOLATILE (arg));
3010
3011 if (!c_mark_addressable (arg))
3012 return error_mark_node;
3013
3014 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
3015 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
3016
3017 argtype = build_pointer_type (argtype);
3018
3019 /* ??? Cope with user tricks that amount to offsetof. Delete this
3020 when we have proper support for integer constant expressions. */
3021 val = get_base_address (arg);
3022 if (val && TREE_CODE (val) == INDIRECT_REF
3023 && TREE_CONSTANT (TREE_OPERAND (val, 0)))
3024 {
3025 tree op0 = fold_convert (argtype, fold_offsetof (arg, val)), op1;
3026
3027 op1 = fold_convert (argtype, TREE_OPERAND (val, 0));
3028 return fold_build2 (PLUS_EXPR, argtype, op0, op1);
3029 }
3030
3031 val = build1 (ADDR_EXPR, argtype, arg);
3032
3033 return val;
3034
3035 default:
3036 gcc_unreachable ();
3037 }
3038
3039 if (argtype == 0)
3040 argtype = TREE_TYPE (arg);
3041 return require_constant_value ? fold_build1_initializer (code, argtype, arg)
3042 : fold_build1 (code, argtype, arg);
3043 }
3044
3045 /* Return nonzero if REF is an lvalue valid for this language.
3046 Lvalues can be assigned, unless their type has TYPE_READONLY.
3047 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
3048
3049 static int
3050 lvalue_p (tree ref)
3051 {
3052 enum tree_code code = TREE_CODE (ref);
3053
3054 switch (code)
3055 {
3056 case REALPART_EXPR:
3057 case IMAGPART_EXPR:
3058 case COMPONENT_REF:
3059 return lvalue_p (TREE_OPERAND (ref, 0));
3060
3061 case COMPOUND_LITERAL_EXPR:
3062 case STRING_CST:
3063 return 1;
3064
3065 case INDIRECT_REF:
3066 case ARRAY_REF:
3067 case VAR_DECL:
3068 case PARM_DECL:
3069 case RESULT_DECL:
3070 case ERROR_MARK:
3071 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3072 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3073
3074 case BIND_EXPR:
3075 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3076
3077 default:
3078 return 0;
3079 }
3080 }
3081 \f
3082 /* Give an error for storing in something that is 'const'. */
3083
3084 static void
3085 readonly_error (tree arg, enum lvalue_use use)
3086 {
3087 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement
3088 || use == lv_asm);
3089 /* Using this macro rather than (for example) arrays of messages
3090 ensures that all the format strings are checked at compile
3091 time. */
3092 #define READONLY_MSG(A, I, D, AS) (use == lv_assign ? (A) \
3093 : (use == lv_increment ? (I) \
3094 : (use == lv_decrement ? (D) : (AS))))
3095 if (TREE_CODE (arg) == COMPONENT_REF)
3096 {
3097 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3098 readonly_error (TREE_OPERAND (arg, 0), use);
3099 else
3100 error (READONLY_MSG (G_("assignment of read-only member %qD"),
3101 G_("increment of read-only member %qD"),
3102 G_("decrement of read-only member %qD"),
3103 G_("read-only member %qD used as %<asm%> output")),
3104 TREE_OPERAND (arg, 1));
3105 }
3106 else if (TREE_CODE (arg) == VAR_DECL)
3107 error (READONLY_MSG (G_("assignment of read-only variable %qD"),
3108 G_("increment of read-only variable %qD"),
3109 G_("decrement of read-only variable %qD"),
3110 G_("read-only variable %qD used as %<asm%> output")),
3111 arg);
3112 else
3113 error (READONLY_MSG (G_("assignment of read-only location"),
3114 G_("increment of read-only location"),
3115 G_("decrement of read-only location"),
3116 G_("read-only location used as %<asm%> output")));
3117 }
3118
3119
3120 /* Return nonzero if REF is an lvalue valid for this language;
3121 otherwise, print an error message and return zero. USE says
3122 how the lvalue is being used and so selects the error message. */
3123
3124 static int
3125 lvalue_or_else (tree ref, enum lvalue_use use)
3126 {
3127 int win = lvalue_p (ref);
3128
3129 if (!win)
3130 lvalue_error (use);
3131
3132 return win;
3133 }
3134 \f
3135 /* Mark EXP saying that we need to be able to take the
3136 address of it; it should not be allocated in a register.
3137 Returns true if successful. */
3138
3139 bool
3140 c_mark_addressable (tree exp)
3141 {
3142 tree x = exp;
3143
3144 while (1)
3145 switch (TREE_CODE (x))
3146 {
3147 case COMPONENT_REF:
3148 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3149 {
3150 error
3151 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
3152 return false;
3153 }
3154
3155 /* ... fall through ... */
3156
3157 case ADDR_EXPR:
3158 case ARRAY_REF:
3159 case REALPART_EXPR:
3160 case IMAGPART_EXPR:
3161 x = TREE_OPERAND (x, 0);
3162 break;
3163
3164 case COMPOUND_LITERAL_EXPR:
3165 case CONSTRUCTOR:
3166 TREE_ADDRESSABLE (x) = 1;
3167 return true;
3168
3169 case VAR_DECL:
3170 case CONST_DECL:
3171 case PARM_DECL:
3172 case RESULT_DECL:
3173 if (C_DECL_REGISTER (x)
3174 && DECL_NONLOCAL (x))
3175 {
3176 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3177 {
3178 error
3179 ("global register variable %qD used in nested function", x);
3180 return false;
3181 }
3182 pedwarn ("register variable %qD used in nested function", x);
3183 }
3184 else if (C_DECL_REGISTER (x))
3185 {
3186 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3187 error ("address of global register variable %qD requested", x);
3188 else
3189 error ("address of register variable %qD requested", x);
3190 return false;
3191 }
3192
3193 /* drops in */
3194 case FUNCTION_DECL:
3195 TREE_ADDRESSABLE (x) = 1;
3196 /* drops out */
3197 default:
3198 return true;
3199 }
3200 }
3201 \f
3202 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3203
3204 tree
3205 build_conditional_expr (tree ifexp, tree op1, tree op2)
3206 {
3207 tree type1;
3208 tree type2;
3209 enum tree_code code1;
3210 enum tree_code code2;
3211 tree result_type = NULL;
3212 tree orig_op1 = op1, orig_op2 = op2;
3213
3214 /* Promote both alternatives. */
3215
3216 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3217 op1 = default_conversion (op1);
3218 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3219 op2 = default_conversion (op2);
3220
3221 if (TREE_CODE (ifexp) == ERROR_MARK
3222 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3223 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3224 return error_mark_node;
3225
3226 type1 = TREE_TYPE (op1);
3227 code1 = TREE_CODE (type1);
3228 type2 = TREE_TYPE (op2);
3229 code2 = TREE_CODE (type2);
3230
3231 /* C90 does not permit non-lvalue arrays in conditional expressions.
3232 In C99 they will be pointers by now. */
3233 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
3234 {
3235 error ("non-lvalue array in conditional expression");
3236 return error_mark_node;
3237 }
3238
3239 /* Quickly detect the usual case where op1 and op2 have the same type
3240 after promotion. */
3241 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3242 {
3243 if (type1 == type2)
3244 result_type = type1;
3245 else
3246 result_type = TYPE_MAIN_VARIANT (type1);
3247 }
3248 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
3249 || code1 == COMPLEX_TYPE)
3250 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3251 || code2 == COMPLEX_TYPE))
3252 {
3253 result_type = c_common_type (type1, type2);
3254
3255 /* If -Wsign-compare, warn here if type1 and type2 have
3256 different signedness. We'll promote the signed to unsigned
3257 and later code won't know it used to be different.
3258 Do this check on the original types, so that explicit casts
3259 will be considered, but default promotions won't. */
3260 if (warn_sign_compare && !skip_evaluation)
3261 {
3262 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3263 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
3264
3265 if (unsigned_op1 ^ unsigned_op2)
3266 {
3267 /* Do not warn if the result type is signed, since the
3268 signed type will only be chosen if it can represent
3269 all the values of the unsigned type. */
3270 if (!TYPE_UNSIGNED (result_type))
3271 /* OK */;
3272 /* Do not warn if the signed quantity is an unsuffixed
3273 integer literal (or some static constant expression
3274 involving such literals) and it is non-negative. */
3275 else if ((unsigned_op2 && tree_expr_nonnegative_p (op1))
3276 || (unsigned_op1 && tree_expr_nonnegative_p (op2)))
3277 /* OK */;
3278 else
3279 warning (0, "signed and unsigned type in conditional expression");
3280 }
3281 }
3282 }
3283 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3284 {
3285 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3286 pedwarn ("ISO C forbids conditional expr with only one void side");
3287 result_type = void_type_node;
3288 }
3289 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3290 {
3291 if (comp_target_types (type1, type2))
3292 result_type = common_pointer_type (type1, type2);
3293 else if (null_pointer_constant_p (orig_op1))
3294 result_type = qualify_type (type2, type1);
3295 else if (null_pointer_constant_p (orig_op2))
3296 result_type = qualify_type (type1, type2);
3297 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3298 {
3299 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3300 pedwarn ("ISO C forbids conditional expr between "
3301 "%<void *%> and function pointer");
3302 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
3303 TREE_TYPE (type2)));
3304 }
3305 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3306 {
3307 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3308 pedwarn ("ISO C forbids conditional expr between "
3309 "%<void *%> and function pointer");
3310 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
3311 TREE_TYPE (type1)));
3312 }
3313 else
3314 {
3315 pedwarn ("pointer type mismatch in conditional expression");
3316 result_type = build_pointer_type (void_type_node);
3317 }
3318 }
3319 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3320 {
3321 if (!null_pointer_constant_p (orig_op2))
3322 pedwarn ("pointer/integer type mismatch in conditional expression");
3323 else
3324 {
3325 op2 = null_pointer_node;
3326 }
3327 result_type = type1;
3328 }
3329 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3330 {
3331 if (!null_pointer_constant_p (orig_op1))
3332 pedwarn ("pointer/integer type mismatch in conditional expression");
3333 else
3334 {
3335 op1 = null_pointer_node;
3336 }
3337 result_type = type2;
3338 }
3339
3340 if (!result_type)
3341 {
3342 if (flag_cond_mismatch)
3343 result_type = void_type_node;
3344 else
3345 {
3346 error ("type mismatch in conditional expression");
3347 return error_mark_node;
3348 }
3349 }
3350
3351 /* Merge const and volatile flags of the incoming types. */
3352 result_type
3353 = build_type_variant (result_type,
3354 TREE_READONLY (op1) || TREE_READONLY (op2),
3355 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3356
3357 if (result_type != TREE_TYPE (op1))
3358 op1 = convert_and_check (result_type, op1);
3359 if (result_type != TREE_TYPE (op2))
3360 op2 = convert_and_check (result_type, op2);
3361
3362 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2);
3363 }
3364 \f
3365 /* Return a compound expression that performs two expressions and
3366 returns the value of the second of them. */
3367
3368 tree
3369 build_compound_expr (tree expr1, tree expr2)
3370 {
3371 if (!TREE_SIDE_EFFECTS (expr1))
3372 {
3373 /* The left-hand operand of a comma expression is like an expression
3374 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3375 any side-effects, unless it was explicitly cast to (void). */
3376 if (warn_unused_value)
3377 {
3378 if (VOID_TYPE_P (TREE_TYPE (expr1))
3379 && (TREE_CODE (expr1) == NOP_EXPR
3380 || TREE_CODE (expr1) == CONVERT_EXPR))
3381 ; /* (void) a, b */
3382 else if (VOID_TYPE_P (TREE_TYPE (expr1))
3383 && TREE_CODE (expr1) == COMPOUND_EXPR
3384 && (TREE_CODE (TREE_OPERAND (expr1, 1)) == CONVERT_EXPR
3385 || TREE_CODE (TREE_OPERAND (expr1, 1)) == NOP_EXPR))
3386 ; /* (void) a, (void) b, c */
3387 else
3388 warning (0, "left-hand operand of comma expression has no effect");
3389 }
3390 }
3391
3392 /* With -Wunused, we should also warn if the left-hand operand does have
3393 side-effects, but computes a value which is not used. For example, in
3394 `foo() + bar(), baz()' the result of the `+' operator is not used,
3395 so we should issue a warning. */
3396 else if (warn_unused_value)
3397 warn_if_unused_value (expr1, input_location);
3398
3399 if (expr2 == error_mark_node)
3400 return error_mark_node;
3401
3402 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
3403 }
3404
3405 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3406
3407 tree
3408 build_c_cast (tree type, tree expr)
3409 {
3410 tree value = expr;
3411
3412 if (type == error_mark_node || expr == error_mark_node)
3413 return error_mark_node;
3414
3415 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3416 only in <protocol> qualifications. But when constructing cast expressions,
3417 the protocols do matter and must be kept around. */
3418 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
3419 return build1 (NOP_EXPR, type, expr);
3420
3421 type = TYPE_MAIN_VARIANT (type);
3422
3423 if (TREE_CODE (type) == ARRAY_TYPE)
3424 {
3425 error ("cast specifies array type");
3426 return error_mark_node;
3427 }
3428
3429 if (TREE_CODE (type) == FUNCTION_TYPE)
3430 {
3431 error ("cast specifies function type");
3432 return error_mark_node;
3433 }
3434
3435 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3436 {
3437 if (pedantic)
3438 {
3439 if (TREE_CODE (type) == RECORD_TYPE
3440 || TREE_CODE (type) == UNION_TYPE)
3441 pedwarn ("ISO C forbids casting nonscalar to the same type");
3442 }
3443 }
3444 else if (TREE_CODE (type) == UNION_TYPE)
3445 {
3446 tree field;
3447
3448 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3449 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3450 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3451 break;
3452
3453 if (field)
3454 {
3455 tree t;
3456
3457 if (pedantic)
3458 pedwarn ("ISO C forbids casts to union type");
3459 t = digest_init (type,
3460 build_constructor_single (type, field, value),
3461 true, 0);
3462 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3463 TREE_INVARIANT (t) = TREE_INVARIANT (value);
3464 return t;
3465 }
3466 error ("cast to union type from type not present in union");
3467 return error_mark_node;
3468 }
3469 else
3470 {
3471 tree otype, ovalue;
3472
3473 if (type == void_type_node)
3474 return build1 (CONVERT_EXPR, type, value);
3475
3476 otype = TREE_TYPE (value);
3477
3478 /* Optionally warn about potentially worrisome casts. */
3479
3480 if (warn_cast_qual
3481 && TREE_CODE (type) == POINTER_TYPE
3482 && TREE_CODE (otype) == POINTER_TYPE)
3483 {
3484 tree in_type = type;
3485 tree in_otype = otype;
3486 int added = 0;
3487 int discarded = 0;
3488
3489 /* Check that the qualifiers on IN_TYPE are a superset of
3490 the qualifiers of IN_OTYPE. The outermost level of
3491 POINTER_TYPE nodes is uninteresting and we stop as soon
3492 as we hit a non-POINTER_TYPE node on either type. */
3493 do
3494 {
3495 in_otype = TREE_TYPE (in_otype);
3496 in_type = TREE_TYPE (in_type);
3497
3498 /* GNU C allows cv-qualified function types. 'const'
3499 means the function is very pure, 'volatile' means it
3500 can't return. We need to warn when such qualifiers
3501 are added, not when they're taken away. */
3502 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3503 && TREE_CODE (in_type) == FUNCTION_TYPE)
3504 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3505 else
3506 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3507 }
3508 while (TREE_CODE (in_type) == POINTER_TYPE
3509 && TREE_CODE (in_otype) == POINTER_TYPE);
3510
3511 if (added)
3512 warning (0, "cast adds new qualifiers to function type");
3513
3514 if (discarded)
3515 /* There are qualifiers present in IN_OTYPE that are not
3516 present in IN_TYPE. */
3517 warning (0, "cast discards qualifiers from pointer target type");
3518 }
3519
3520 /* Warn about possible alignment problems. */
3521 if (STRICT_ALIGNMENT
3522 && TREE_CODE (type) == POINTER_TYPE
3523 && TREE_CODE (otype) == POINTER_TYPE
3524 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3525 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3526 /* Don't warn about opaque types, where the actual alignment
3527 restriction is unknown. */
3528 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3529 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3530 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3531 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3532 warning (OPT_Wcast_align,
3533 "cast increases required alignment of target type");
3534
3535 if (TREE_CODE (type) == INTEGER_TYPE
3536 && TREE_CODE (otype) == POINTER_TYPE
3537 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
3538 /* Unlike conversion of integers to pointers, where the
3539 warning is disabled for converting constants because
3540 of cases such as SIG_*, warn about converting constant
3541 pointers to integers. In some cases it may cause unwanted
3542 sign extension, and a warning is appropriate. */
3543 warning (OPT_Wpointer_to_int_cast,
3544 "cast from pointer to integer of different size");
3545
3546 if (TREE_CODE (value) == CALL_EXPR
3547 && TREE_CODE (type) != TREE_CODE (otype))
3548 warning (OPT_Wbad_function_cast, "cast from function call of type %qT "
3549 "to non-matching type %qT", otype, type);
3550
3551 if (TREE_CODE (type) == POINTER_TYPE
3552 && TREE_CODE (otype) == INTEGER_TYPE
3553 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3554 /* Don't warn about converting any constant. */
3555 && !TREE_CONSTANT (value))
3556 warning (OPT_Wint_to_pointer_cast, "cast to pointer from integer "
3557 "of different size");
3558
3559 strict_aliasing_warning (otype, type, expr);
3560
3561 /* If pedantic, warn for conversions between function and object
3562 pointer types, except for converting a null pointer constant
3563 to function pointer type. */
3564 if (pedantic
3565 && TREE_CODE (type) == POINTER_TYPE
3566 && TREE_CODE (otype) == POINTER_TYPE
3567 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3568 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3569 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3570
3571 if (pedantic
3572 && TREE_CODE (type) == POINTER_TYPE
3573 && TREE_CODE (otype) == POINTER_TYPE
3574 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3575 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3576 && !null_pointer_constant_p (value))
3577 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3578
3579 ovalue = value;
3580 value = convert (type, value);
3581
3582 /* Ignore any integer overflow caused by the cast. */
3583 if (TREE_CODE (value) == INTEGER_CST)
3584 {
3585 if (CONSTANT_CLASS_P (ovalue)
3586 && (TREE_OVERFLOW (ovalue) || TREE_CONSTANT_OVERFLOW (ovalue)))
3587 {
3588 /* Avoid clobbering a shared constant. */
3589 value = copy_node (value);
3590 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3591 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3592 }
3593 else if (TREE_OVERFLOW (value) || TREE_CONSTANT_OVERFLOW (value))
3594 /* Reset VALUE's overflow flags, ensuring constant sharing. */
3595 value = build_int_cst_wide (TREE_TYPE (value),
3596 TREE_INT_CST_LOW (value),
3597 TREE_INT_CST_HIGH (value));
3598 }
3599 }
3600
3601 /* Don't let a cast be an lvalue. */
3602 if (value == expr)
3603 value = non_lvalue (value);
3604
3605 return value;
3606 }
3607
3608 /* Interpret a cast of expression EXPR to type TYPE. */
3609 tree
3610 c_cast_expr (struct c_type_name *type_name, tree expr)
3611 {
3612 tree type;
3613 int saved_wsp = warn_strict_prototypes;
3614
3615 /* This avoids warnings about unprototyped casts on
3616 integers. E.g. "#define SIG_DFL (void(*)())0". */
3617 if (TREE_CODE (expr) == INTEGER_CST)
3618 warn_strict_prototypes = 0;
3619 type = groktypename (type_name);
3620 warn_strict_prototypes = saved_wsp;
3621
3622 return build_c_cast (type, expr);
3623 }
3624 \f
3625 /* Build an assignment expression of lvalue LHS from value RHS.
3626 MODIFYCODE is the code for a binary operator that we use
3627 to combine the old value of LHS with RHS to get the new value.
3628 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3629
3630 tree
3631 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3632 {
3633 tree result;
3634 tree newrhs;
3635 tree lhstype = TREE_TYPE (lhs);
3636 tree olhstype = lhstype;
3637
3638 /* Types that aren't fully specified cannot be used in assignments. */
3639 lhs = require_complete_type (lhs);
3640
3641 /* Avoid duplicate error messages from operands that had errors. */
3642 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3643 return error_mark_node;
3644
3645 if (!lvalue_or_else (lhs, lv_assign))
3646 return error_mark_node;
3647
3648 STRIP_TYPE_NOPS (rhs);
3649
3650 newrhs = rhs;
3651
3652 /* If a binary op has been requested, combine the old LHS value with the RHS
3653 producing the value we should actually store into the LHS. */
3654
3655 if (modifycode != NOP_EXPR)
3656 {
3657 lhs = stabilize_reference (lhs);
3658 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3659 }
3660
3661 /* Give an error for storing in something that is 'const'. */
3662
3663 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3664 || ((TREE_CODE (lhstype) == RECORD_TYPE
3665 || TREE_CODE (lhstype) == UNION_TYPE)
3666 && C_TYPE_FIELDS_READONLY (lhstype)))
3667 {
3668 readonly_error (lhs, lv_assign);
3669 return error_mark_node;
3670 }
3671
3672 /* If storing into a structure or union member,
3673 it has probably been given type `int'.
3674 Compute the type that would go with
3675 the actual amount of storage the member occupies. */
3676
3677 if (TREE_CODE (lhs) == COMPONENT_REF
3678 && (TREE_CODE (lhstype) == INTEGER_TYPE
3679 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3680 || TREE_CODE (lhstype) == REAL_TYPE
3681 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3682 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3683
3684 /* If storing in a field that is in actuality a short or narrower than one,
3685 we must store in the field in its actual type. */
3686
3687 if (lhstype != TREE_TYPE (lhs))
3688 {
3689 lhs = copy_node (lhs);
3690 TREE_TYPE (lhs) = lhstype;
3691 }
3692
3693 /* Convert new value to destination type. */
3694
3695 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign,
3696 NULL_TREE, NULL_TREE, 0);
3697 if (TREE_CODE (newrhs) == ERROR_MARK)
3698 return error_mark_node;
3699
3700 /* Emit ObjC write barrier, if necessary. */
3701 if (c_dialect_objc () && flag_objc_gc)
3702 {
3703 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
3704 if (result)
3705 return result;
3706 }
3707
3708 /* Scan operands. */
3709
3710 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
3711 TREE_SIDE_EFFECTS (result) = 1;
3712
3713 /* If we got the LHS in a different type for storing in,
3714 convert the result back to the nominal type of LHS
3715 so that the value we return always has the same type
3716 as the LHS argument. */
3717
3718 if (olhstype == TREE_TYPE (result))
3719 return result;
3720 return convert_for_assignment (olhstype, result, ic_assign,
3721 NULL_TREE, NULL_TREE, 0);
3722 }
3723 \f
3724 /* Convert value RHS to type TYPE as preparation for an assignment
3725 to an lvalue of type TYPE.
3726 The real work of conversion is done by `convert'.
3727 The purpose of this function is to generate error messages
3728 for assignments that are not allowed in C.
3729 ERRTYPE says whether it is argument passing, assignment,
3730 initialization or return.
3731
3732 FUNCTION is a tree for the function being called.
3733 PARMNUM is the number of the argument, for printing in error messages. */
3734
3735 static tree
3736 convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
3737 tree fundecl, tree function, int parmnum)
3738 {
3739 enum tree_code codel = TREE_CODE (type);
3740 tree rhstype;
3741 enum tree_code coder;
3742 tree rname = NULL_TREE;
3743 bool objc_ok = false;
3744
3745 if (errtype == ic_argpass || errtype == ic_argpass_nonproto)
3746 {
3747 tree selector;
3748 /* Change pointer to function to the function itself for
3749 diagnostics. */
3750 if (TREE_CODE (function) == ADDR_EXPR
3751 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
3752 function = TREE_OPERAND (function, 0);
3753
3754 /* Handle an ObjC selector specially for diagnostics. */
3755 selector = objc_message_selector ();
3756 rname = function;
3757 if (selector && parmnum > 2)
3758 {
3759 rname = selector;
3760 parmnum -= 2;
3761 }
3762 }
3763
3764 /* This macro is used to emit diagnostics to ensure that all format
3765 strings are complete sentences, visible to gettext and checked at
3766 compile time. */
3767 #define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \
3768 do { \
3769 switch (errtype) \
3770 { \
3771 case ic_argpass: \
3772 pedwarn (AR, parmnum, rname); \
3773 break; \
3774 case ic_argpass_nonproto: \
3775 warning (0, AR, parmnum, rname); \
3776 break; \
3777 case ic_assign: \
3778 pedwarn (AS); \
3779 break; \
3780 case ic_init: \
3781 pedwarn (IN); \
3782 break; \
3783 case ic_return: \
3784 pedwarn (RE); \
3785 break; \
3786 default: \
3787 gcc_unreachable (); \
3788 } \
3789 } while (0)
3790
3791 STRIP_TYPE_NOPS (rhs);
3792
3793 if (optimize && TREE_CODE (rhs) == VAR_DECL
3794 && TREE_CODE (TREE_TYPE (rhs)) != ARRAY_TYPE)
3795 rhs = decl_constant_value_for_broken_optimization (rhs);
3796
3797 rhstype = TREE_TYPE (rhs);
3798 coder = TREE_CODE (rhstype);
3799
3800 if (coder == ERROR_MARK)
3801 return error_mark_node;
3802
3803 if (c_dialect_objc ())
3804 {
3805 int parmno;
3806
3807 switch (errtype)
3808 {
3809 case ic_return:
3810 parmno = 0;
3811 break;
3812
3813 case ic_assign:
3814 parmno = -1;
3815 break;
3816
3817 case ic_init:
3818 parmno = -2;
3819 break;
3820
3821 default:
3822 parmno = parmnum;
3823 break;
3824 }
3825
3826 objc_ok = objc_compare_types (type, rhstype, parmno, rname);
3827 }
3828
3829 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3830 {
3831 overflow_warning (rhs);
3832 return rhs;
3833 }
3834
3835 if (coder == VOID_TYPE)
3836 {
3837 /* Except for passing an argument to an unprototyped function,
3838 this is a constraint violation. When passing an argument to
3839 an unprototyped function, it is compile-time undefined;
3840 making it a constraint in that case was rejected in
3841 DR#252. */
3842 error ("void value not ignored as it ought to be");
3843 return error_mark_node;
3844 }
3845 /* A type converts to a reference to it.
3846 This code doesn't fully support references, it's just for the
3847 special case of va_start and va_copy. */
3848 if (codel == REFERENCE_TYPE
3849 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
3850 {
3851 if (!lvalue_p (rhs))
3852 {
3853 error ("cannot pass rvalue to reference parameter");
3854 return error_mark_node;
3855 }
3856 if (!c_mark_addressable (rhs))
3857 return error_mark_node;
3858 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
3859
3860 /* We already know that these two types are compatible, but they
3861 may not be exactly identical. In fact, `TREE_TYPE (type)' is
3862 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
3863 likely to be va_list, a typedef to __builtin_va_list, which
3864 is different enough that it will cause problems later. */
3865 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
3866 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
3867
3868 rhs = build1 (NOP_EXPR, type, rhs);
3869 return rhs;
3870 }
3871 /* Some types can interconvert without explicit casts. */
3872 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
3873 && vector_types_convertible_p (type, TREE_TYPE (rhs)))
3874 return convert (type, rhs);
3875 /* Arithmetic types all interconvert, and enum is treated like int. */
3876 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
3877 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
3878 || codel == BOOLEAN_TYPE)
3879 && (coder == INTEGER_TYPE || coder == REAL_TYPE
3880 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
3881 || coder == BOOLEAN_TYPE))
3882 return convert_and_check (type, rhs);
3883
3884 /* Conversion to a transparent union from its member types.
3885 This applies only to function arguments. */
3886 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type)
3887 && (errtype == ic_argpass || errtype == ic_argpass_nonproto))
3888 {
3889 tree memb, marginal_memb = NULL_TREE;
3890
3891 for (memb = TYPE_FIELDS (type); memb ; memb = TREE_CHAIN (memb))
3892 {
3893 tree memb_type = TREE_TYPE (memb);
3894
3895 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
3896 TYPE_MAIN_VARIANT (rhstype)))
3897 break;
3898
3899 if (TREE_CODE (memb_type) != POINTER_TYPE)
3900 continue;
3901
3902 if (coder == POINTER_TYPE)
3903 {
3904 tree ttl = TREE_TYPE (memb_type);
3905 tree ttr = TREE_TYPE (rhstype);
3906
3907 /* Any non-function converts to a [const][volatile] void *
3908 and vice versa; otherwise, targets must be the same.
3909 Meanwhile, the lhs target must have all the qualifiers of
3910 the rhs. */
3911 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3912 || comp_target_types (memb_type, rhstype))
3913 {
3914 /* If this type won't generate any warnings, use it. */
3915 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
3916 || ((TREE_CODE (ttr) == FUNCTION_TYPE
3917 && TREE_CODE (ttl) == FUNCTION_TYPE)
3918 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3919 == TYPE_QUALS (ttr))
3920 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3921 == TYPE_QUALS (ttl))))
3922 break;
3923
3924 /* Keep looking for a better type, but remember this one. */
3925 if (!marginal_memb)
3926 marginal_memb = memb;
3927 }
3928 }
3929
3930 /* Can convert integer zero to any pointer type. */
3931 if (null_pointer_constant_p (rhs))
3932 {
3933 rhs = null_pointer_node;
3934 break;
3935 }
3936 }
3937
3938 if (memb || marginal_memb)
3939 {
3940 if (!memb)
3941 {
3942 /* We have only a marginally acceptable member type;
3943 it needs a warning. */
3944 tree ttl = TREE_TYPE (TREE_TYPE (marginal_memb));
3945 tree ttr = TREE_TYPE (rhstype);
3946
3947 /* Const and volatile mean something different for function
3948 types, so the usual warnings are not appropriate. */
3949 if (TREE_CODE (ttr) == FUNCTION_TYPE
3950 && TREE_CODE (ttl) == FUNCTION_TYPE)
3951 {
3952 /* Because const and volatile on functions are
3953 restrictions that say the function will not do
3954 certain things, it is okay to use a const or volatile
3955 function where an ordinary one is wanted, but not
3956 vice-versa. */
3957 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3958 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE "
3959 "makes qualified function "
3960 "pointer from unqualified"),
3961 G_("assignment makes qualified "
3962 "function pointer from "
3963 "unqualified"),
3964 G_("initialization makes qualified "
3965 "function pointer from "
3966 "unqualified"),
3967 G_("return makes qualified function "
3968 "pointer from unqualified"));
3969 }
3970 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3971 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
3972 "qualifiers from pointer target type"),
3973 G_("assignment discards qualifiers "
3974 "from pointer target type"),
3975 G_("initialization discards qualifiers "
3976 "from pointer target type"),
3977 G_("return discards qualifiers from "
3978 "pointer target type"));
3979
3980 memb = marginal_memb;
3981 }
3982
3983 if (pedantic && (!fundecl || !DECL_IN_SYSTEM_HEADER (fundecl)))
3984 pedwarn ("ISO C prohibits argument conversion to union type");
3985
3986 return build_constructor_single (type, memb, rhs);
3987 }
3988 }
3989
3990 /* Conversions among pointers */
3991 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
3992 && (coder == codel))
3993 {
3994 tree ttl = TREE_TYPE (type);
3995 tree ttr = TREE_TYPE (rhstype);
3996 tree mvl = ttl;
3997 tree mvr = ttr;
3998 bool is_opaque_pointer;
3999 int target_cmp = 0; /* Cache comp_target_types () result. */
4000
4001 if (TREE_CODE (mvl) != ARRAY_TYPE)
4002 mvl = TYPE_MAIN_VARIANT (mvl);
4003 if (TREE_CODE (mvr) != ARRAY_TYPE)
4004 mvr = TYPE_MAIN_VARIANT (mvr);
4005 /* Opaque pointers are treated like void pointers. */
4006 is_opaque_pointer = (targetm.vector_opaque_p (type)
4007 || targetm.vector_opaque_p (rhstype))
4008 && TREE_CODE (ttl) == VECTOR_TYPE
4009 && TREE_CODE (ttr) == VECTOR_TYPE;
4010
4011 /* C++ does not allow the implicit conversion void* -> T*. However,
4012 for the purpose of reducing the number of false positives, we
4013 tolerate the special case of
4014
4015 int *p = NULL;
4016
4017 where NULL is typically defined in C to be '(void *) 0'. */
4018 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl))
4019 warning (OPT_Wc___compat, "request for implicit conversion from "
4020 "%qT to %qT not permitted in C++", rhstype, type);
4021
4022 /* Check if the right-hand side has a format attribute but the
4023 left-hand side doesn't. */
4024 if (warn_missing_format_attribute
4025 && check_missing_format_attribute (type, rhstype))
4026 {
4027 switch (errtype)
4028 {
4029 case ic_argpass:
4030 case ic_argpass_nonproto:
4031 warning (OPT_Wmissing_format_attribute,
4032 "argument %d of %qE might be "
4033 "a candidate for a format attribute",
4034 parmnum, rname);
4035 break;
4036 case ic_assign:
4037 warning (OPT_Wmissing_format_attribute,
4038 "assignment left-hand side might be "
4039 "a candidate for a format attribute");
4040 break;
4041 case ic_init:
4042 warning (OPT_Wmissing_format_attribute,
4043 "initialization left-hand side might be "
4044 "a candidate for a format attribute");
4045 break;
4046 case ic_return:
4047 warning (OPT_Wmissing_format_attribute,
4048 "return type might be "
4049 "a candidate for a format attribute");
4050 break;
4051 default:
4052 gcc_unreachable ();
4053 }
4054 }
4055
4056 /* Any non-function converts to a [const][volatile] void *
4057 and vice versa; otherwise, targets must be the same.
4058 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4059 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4060 || (target_cmp = comp_target_types (type, rhstype))
4061 || is_opaque_pointer
4062 || (c_common_unsigned_type (mvl)
4063 == c_common_unsigned_type (mvr)))
4064 {
4065 if (pedantic
4066 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
4067 ||
4068 (VOID_TYPE_P (ttr)
4069 && !null_pointer_constant_p (rhs)
4070 && TREE_CODE (ttl) == FUNCTION_TYPE)))
4071 WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of "
4072 "%qE between function pointer "
4073 "and %<void *%>"),
4074 G_("ISO C forbids assignment between "
4075 "function pointer and %<void *%>"),
4076 G_("ISO C forbids initialization between "
4077 "function pointer and %<void *%>"),
4078 G_("ISO C forbids return between function "
4079 "pointer and %<void *%>"));
4080 /* Const and volatile mean something different for function types,
4081 so the usual warnings are not appropriate. */
4082 else if (TREE_CODE (ttr) != FUNCTION_TYPE
4083 && TREE_CODE (ttl) != FUNCTION_TYPE)
4084 {
4085 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4086 {
4087 /* Types differing only by the presence of the 'volatile'
4088 qualifier are acceptable if the 'volatile' has been added
4089 in by the Objective-C EH machinery. */
4090 if (!objc_type_quals_match (ttl, ttr))
4091 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
4092 "qualifiers from pointer target type"),
4093 G_("assignment discards qualifiers "
4094 "from pointer target type"),
4095 G_("initialization discards qualifiers "
4096 "from pointer target type"),
4097 G_("return discards qualifiers from "
4098 "pointer target type"));
4099 }
4100 /* If this is not a case of ignoring a mismatch in signedness,
4101 no warning. */
4102 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4103 || target_cmp)
4104 ;
4105 /* If there is a mismatch, do warn. */
4106 else if (warn_pointer_sign)
4107 WARN_FOR_ASSIGNMENT (G_("pointer targets in passing argument "
4108 "%d of %qE differ in signedness"),
4109 G_("pointer targets in assignment "
4110 "differ in signedness"),
4111 G_("pointer targets in initialization "
4112 "differ in signedness"),
4113 G_("pointer targets in return differ "
4114 "in signedness"));
4115 }
4116 else if (TREE_CODE (ttl) == FUNCTION_TYPE
4117 && TREE_CODE (ttr) == FUNCTION_TYPE)
4118 {
4119 /* Because const and volatile on functions are restrictions
4120 that say the function will not do certain things,
4121 it is okay to use a const or volatile function
4122 where an ordinary one is wanted, but not vice-versa. */
4123 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4124 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
4125 "qualified function pointer "
4126 "from unqualified"),
4127 G_("assignment makes qualified function "
4128 "pointer from unqualified"),
4129 G_("initialization makes qualified "
4130 "function pointer from unqualified"),
4131 G_("return makes qualified function "
4132 "pointer from unqualified"));
4133 }
4134 }
4135 else
4136 /* Avoid warning about the volatile ObjC EH puts on decls. */
4137 if (!objc_ok)
4138 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE from "
4139 "incompatible pointer type"),
4140 G_("assignment from incompatible pointer type"),
4141 G_("initialization from incompatible "
4142 "pointer type"),
4143 G_("return from incompatible pointer type"));
4144
4145 return convert (type, rhs);
4146 }
4147 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
4148 {
4149 /* ??? This should not be an error when inlining calls to
4150 unprototyped functions. */
4151 error ("invalid use of non-lvalue array");
4152 return error_mark_node;
4153 }
4154 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
4155 {
4156 /* An explicit constant 0 can convert to a pointer,
4157 or one that results from arithmetic, even including
4158 a cast to integer type. */
4159 if (!null_pointer_constant_p (rhs))
4160 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
4161 "pointer from integer without a cast"),
4162 G_("assignment makes pointer from integer "
4163 "without a cast"),
4164 G_("initialization makes pointer from "
4165 "integer without a cast"),
4166 G_("return makes pointer from integer "
4167 "without a cast"));
4168
4169 return convert (type, rhs);
4170 }
4171 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
4172 {
4173 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes integer "
4174 "from pointer without a cast"),
4175 G_("assignment makes integer from pointer "
4176 "without a cast"),
4177 G_("initialization makes integer from pointer "
4178 "without a cast"),
4179 G_("return makes integer from pointer "
4180 "without a cast"));
4181 return convert (type, rhs);
4182 }
4183 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
4184 return convert (type, rhs);
4185
4186 switch (errtype)
4187 {
4188 case ic_argpass:
4189 case ic_argpass_nonproto:
4190 /* ??? This should not be an error when inlining calls to
4191 unprototyped functions. */
4192 error ("incompatible type for argument %d of %qE", parmnum, rname);
4193 break;
4194 case ic_assign:
4195 error ("incompatible types in assignment");
4196 break;
4197 case ic_init:
4198 error ("incompatible types in initialization");
4199 break;
4200 case ic_return:
4201 error ("incompatible types in return");
4202 break;
4203 default:
4204 gcc_unreachable ();
4205 }
4206
4207 return error_mark_node;
4208 }
4209
4210 /* Convert VALUE for assignment into inlined parameter PARM. ARGNUM
4211 is used for error and warning reporting and indicates which argument
4212 is being processed. */
4213
4214 tree
4215 c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum)
4216 {
4217 tree ret, type;
4218
4219 /* If FN was prototyped at the call site, the value has been converted
4220 already in convert_arguments.
4221 However, we might see a prototype now that was not in place when
4222 the function call was seen, so check that the VALUE actually matches
4223 PARM before taking an early exit. */
4224 if (!value
4225 || (TYPE_ARG_TYPES (TREE_TYPE (fn))
4226 && (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
4227 == TYPE_MAIN_VARIANT (TREE_TYPE (value)))))
4228 return value;
4229
4230 type = TREE_TYPE (parm);
4231 ret = convert_for_assignment (type, value,
4232 ic_argpass_nonproto, fn,
4233 fn, argnum);
4234 if (targetm.calls.promote_prototypes (TREE_TYPE (fn))
4235 && INTEGRAL_TYPE_P (type)
4236 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
4237 ret = default_conversion (ret);
4238 return ret;
4239 }
4240 \f
4241 /* If VALUE is a compound expr all of whose expressions are constant, then
4242 return its value. Otherwise, return error_mark_node.
4243
4244 This is for handling COMPOUND_EXPRs as initializer elements
4245 which is allowed with a warning when -pedantic is specified. */
4246
4247 static tree
4248 valid_compound_expr_initializer (tree value, tree endtype)
4249 {
4250 if (TREE_CODE (value) == COMPOUND_EXPR)
4251 {
4252 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4253 == error_mark_node)
4254 return error_mark_node;
4255 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4256 endtype);
4257 }
4258 else if (!initializer_constant_valid_p (value, endtype))
4259 return error_mark_node;
4260 else
4261 return value;
4262 }
4263 \f
4264 /* Perform appropriate conversions on the initial value of a variable,
4265 store it in the declaration DECL,
4266 and print any error messages that are appropriate.
4267 If the init is invalid, store an ERROR_MARK. */
4268
4269 void
4270 store_init_value (tree decl, tree init)
4271 {
4272 tree value, type;
4273
4274 /* If variable's type was invalidly declared, just ignore it. */
4275
4276 type = TREE_TYPE (decl);
4277 if (TREE_CODE (type) == ERROR_MARK)
4278 return;
4279
4280 /* Digest the specified initializer into an expression. */
4281
4282 value = digest_init (type, init, true, TREE_STATIC (decl));
4283
4284 /* Store the expression if valid; else report error. */
4285
4286 if (!in_system_header
4287 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
4288 warning (OPT_Wtraditional, "traditional C rejects automatic "
4289 "aggregate initialization");
4290
4291 DECL_INITIAL (decl) = value;
4292
4293 /* ANSI wants warnings about out-of-range constant initializers. */
4294 STRIP_TYPE_NOPS (value);
4295 constant_expression_warning (value);
4296
4297 /* Check if we need to set array size from compound literal size. */
4298 if (TREE_CODE (type) == ARRAY_TYPE
4299 && TYPE_DOMAIN (type) == 0
4300 && value != error_mark_node)
4301 {
4302 tree inside_init = init;
4303
4304 STRIP_TYPE_NOPS (inside_init);
4305 inside_init = fold (inside_init);
4306
4307 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4308 {
4309 tree cldecl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4310
4311 if (TYPE_DOMAIN (TREE_TYPE (cldecl)))
4312 {
4313 /* For int foo[] = (int [3]){1}; we need to set array size
4314 now since later on array initializer will be just the
4315 brace enclosed list of the compound literal. */
4316 type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
4317 TREE_TYPE (decl) = type;
4318 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (cldecl));
4319 layout_type (type);
4320 layout_decl (cldecl, 0);
4321 }
4322 }
4323 }
4324 }
4325 \f
4326 /* Methods for storing and printing names for error messages. */
4327
4328 /* Implement a spelling stack that allows components of a name to be pushed
4329 and popped. Each element on the stack is this structure. */
4330
4331 struct spelling
4332 {
4333 int kind;
4334 union
4335 {
4336 unsigned HOST_WIDE_INT i;
4337 const char *s;
4338 } u;
4339 };
4340
4341 #define SPELLING_STRING 1
4342 #define SPELLING_MEMBER 2
4343 #define SPELLING_BOUNDS 3
4344
4345 static struct spelling *spelling; /* Next stack element (unused). */
4346 static struct spelling *spelling_base; /* Spelling stack base. */
4347 static int spelling_size; /* Size of the spelling stack. */
4348
4349 /* Macros to save and restore the spelling stack around push_... functions.
4350 Alternative to SAVE_SPELLING_STACK. */
4351
4352 #define SPELLING_DEPTH() (spelling - spelling_base)
4353 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4354
4355 /* Push an element on the spelling stack with type KIND and assign VALUE
4356 to MEMBER. */
4357
4358 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4359 { \
4360 int depth = SPELLING_DEPTH (); \
4361 \
4362 if (depth >= spelling_size) \
4363 { \
4364 spelling_size += 10; \
4365 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
4366 spelling_size); \
4367 RESTORE_SPELLING_DEPTH (depth); \
4368 } \
4369 \
4370 spelling->kind = (KIND); \
4371 spelling->MEMBER = (VALUE); \
4372 spelling++; \
4373 }
4374
4375 /* Push STRING on the stack. Printed literally. */
4376
4377 static void
4378 push_string (const char *string)
4379 {
4380 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4381 }
4382
4383 /* Push a member name on the stack. Printed as '.' STRING. */
4384
4385 static void
4386 push_member_name (tree decl)
4387 {
4388 const char *const string
4389 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4390 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4391 }
4392
4393 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4394
4395 static void
4396 push_array_bounds (unsigned HOST_WIDE_INT bounds)
4397 {
4398 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4399 }
4400
4401 /* Compute the maximum size in bytes of the printed spelling. */
4402
4403 static int
4404 spelling_length (void)
4405 {
4406 int size = 0;
4407 struct spelling *p;
4408
4409 for (p = spelling_base; p < spelling; p++)
4410 {
4411 if (p->kind == SPELLING_BOUNDS)
4412 size += 25;
4413 else
4414 size += strlen (p->u.s) + 1;
4415 }
4416
4417 return size;
4418 }
4419
4420 /* Print the spelling to BUFFER and return it. */
4421
4422 static char *
4423 print_spelling (char *buffer)
4424 {
4425 char *d = buffer;
4426 struct spelling *p;
4427
4428 for (p = spelling_base; p < spelling; p++)
4429 if (p->kind == SPELLING_BOUNDS)
4430 {
4431 sprintf (d, "[" HOST_WIDE_INT_PRINT_UNSIGNED "]", p->u.i);
4432 d += strlen (d);
4433 }
4434 else
4435 {
4436 const char *s;
4437 if (p->kind == SPELLING_MEMBER)
4438 *d++ = '.';
4439 for (s = p->u.s; (*d = *s++); d++)
4440 ;
4441 }
4442 *d++ = '\0';
4443 return buffer;
4444 }
4445
4446 /* Issue an error message for a bad initializer component.
4447 MSGID identifies the message.
4448 The component name is taken from the spelling stack. */
4449
4450 void
4451 error_init (const char *msgid)
4452 {
4453 char *ofwhat;
4454
4455 error ("%s", _(msgid));
4456 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4457 if (*ofwhat)
4458 error ("(near initialization for %qs)", ofwhat);
4459 }
4460
4461 /* Issue a pedantic warning for a bad initializer component.
4462 MSGID identifies the message.
4463 The component name is taken from the spelling stack. */
4464
4465 void
4466 pedwarn_init (const char *msgid)
4467 {
4468 char *ofwhat;
4469
4470 pedwarn ("%s", _(msgid));
4471 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4472 if (*ofwhat)
4473 pedwarn ("(near initialization for %qs)", ofwhat);
4474 }
4475
4476 /* Issue a warning for a bad initializer component.
4477 MSGID identifies the message.
4478 The component name is taken from the spelling stack. */
4479
4480 static void
4481 warning_init (const char *msgid)
4482 {
4483 char *ofwhat;
4484
4485 warning (0, "%s", _(msgid));
4486 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4487 if (*ofwhat)
4488 warning (0, "(near initialization for %qs)", ofwhat);
4489 }
4490 \f
4491 /* If TYPE is an array type and EXPR is a parenthesized string
4492 constant, warn if pedantic that EXPR is being used to initialize an
4493 object of type TYPE. */
4494
4495 void
4496 maybe_warn_string_init (tree type, struct c_expr expr)
4497 {
4498 if (pedantic
4499 && TREE_CODE (type) == ARRAY_TYPE
4500 && TREE_CODE (expr.value) == STRING_CST
4501 && expr.original_code != STRING_CST)
4502 pedwarn_init ("array initialized from parenthesized string constant");
4503 }
4504
4505 /* Digest the parser output INIT as an initializer for type TYPE.
4506 Return a C expression of type TYPE to represent the initial value.
4507
4508 If INIT is a string constant, STRICT_STRING is true if it is
4509 unparenthesized or we should not warn here for it being parenthesized.
4510 For other types of INIT, STRICT_STRING is not used.
4511
4512 REQUIRE_CONSTANT requests an error if non-constant initializers or
4513 elements are seen. */
4514
4515 static tree
4516 digest_init (tree type, tree init, bool strict_string, int require_constant)
4517 {
4518 enum tree_code code = TREE_CODE (type);
4519 tree inside_init = init;
4520
4521 if (type == error_mark_node
4522 || !init
4523 || init == error_mark_node
4524 || TREE_TYPE (init) == error_mark_node)
4525 return error_mark_node;
4526
4527 STRIP_TYPE_NOPS (inside_init);
4528
4529 inside_init = fold (inside_init);
4530
4531 /* Initialization of an array of chars from a string constant
4532 optionally enclosed in braces. */
4533
4534 if (code == ARRAY_TYPE && inside_init
4535 && TREE_CODE (inside_init) == STRING_CST)
4536 {
4537 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4538 /* Note that an array could be both an array of character type
4539 and an array of wchar_t if wchar_t is signed char or unsigned
4540 char. */
4541 bool char_array = (typ1 == char_type_node
4542 || typ1 == signed_char_type_node
4543 || typ1 == unsigned_char_type_node);
4544 bool wchar_array = !!comptypes (typ1, wchar_type_node);
4545 if (char_array || wchar_array)
4546 {
4547 struct c_expr expr;
4548 bool char_string;
4549 expr.value = inside_init;
4550 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
4551 maybe_warn_string_init (type, expr);
4552
4553 char_string
4554 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4555 == char_type_node);
4556
4557 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4558 TYPE_MAIN_VARIANT (type)))
4559 return inside_init;
4560
4561 if (!wchar_array && !char_string)
4562 {
4563 error_init ("char-array initialized from wide string");
4564 return error_mark_node;
4565 }
4566 if (char_string && !char_array)
4567 {
4568 error_init ("wchar_t-array initialized from non-wide string");
4569 return error_mark_node;
4570 }
4571
4572 TREE_TYPE (inside_init) = type;
4573 if (TYPE_DOMAIN (type) != 0
4574 && TYPE_SIZE (type) != 0
4575 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4576 /* Subtract 1 (or sizeof (wchar_t))
4577 because it's ok to ignore the terminating null char
4578 that is counted in the length of the constant. */
4579 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4580 TREE_STRING_LENGTH (inside_init)
4581 - ((TYPE_PRECISION (typ1)
4582 != TYPE_PRECISION (char_type_node))
4583 ? (TYPE_PRECISION (wchar_type_node)
4584 / BITS_PER_UNIT)
4585 : 1)))
4586 pedwarn_init ("initializer-string for array of chars is too long");
4587
4588 return inside_init;
4589 }
4590 else if (INTEGRAL_TYPE_P (typ1))
4591 {
4592 error_init ("array of inappropriate type initialized "
4593 "from string constant");
4594 return error_mark_node;
4595 }
4596 }
4597
4598 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4599 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4600 below and handle as a constructor. */
4601 if (code == VECTOR_TYPE
4602 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
4603 && vector_types_convertible_p (TREE_TYPE (inside_init), type)
4604 && TREE_CONSTANT (inside_init))
4605 {
4606 if (TREE_CODE (inside_init) == VECTOR_CST
4607 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4608 TYPE_MAIN_VARIANT (type)))
4609 return inside_init;
4610
4611 if (TREE_CODE (inside_init) == CONSTRUCTOR)
4612 {
4613 unsigned HOST_WIDE_INT ix;
4614 tree value;
4615 bool constant_p = true;
4616
4617 /* Iterate through elements and check if all constructor
4618 elements are *_CSTs. */
4619 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (inside_init), ix, value)
4620 if (!CONSTANT_CLASS_P (value))
4621 {
4622 constant_p = false;
4623 break;
4624 }
4625
4626 if (constant_p)
4627 return build_vector_from_ctor (type,
4628 CONSTRUCTOR_ELTS (inside_init));
4629 }
4630 }
4631
4632 /* Any type can be initialized
4633 from an expression of the same type, optionally with braces. */
4634
4635 if (inside_init && TREE_TYPE (inside_init) != 0
4636 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4637 TYPE_MAIN_VARIANT (type))
4638 || (code == ARRAY_TYPE
4639 && comptypes (TREE_TYPE (inside_init), type))
4640 || (code == VECTOR_TYPE
4641 && comptypes (TREE_TYPE (inside_init), type))
4642 || (code == POINTER_TYPE
4643 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4644 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4645 TREE_TYPE (type)))))
4646 {
4647 if (code == POINTER_TYPE)
4648 {
4649 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4650 {
4651 if (TREE_CODE (inside_init) == STRING_CST
4652 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4653 inside_init = array_to_pointer_conversion (inside_init);
4654 else
4655 {
4656 error_init ("invalid use of non-lvalue array");
4657 return error_mark_node;
4658 }
4659 }
4660 }
4661
4662 if (code == VECTOR_TYPE)
4663 /* Although the types are compatible, we may require a
4664 conversion. */
4665 inside_init = convert (type, inside_init);
4666
4667 if (require_constant
4668 && (code == VECTOR_TYPE || !flag_isoc99)
4669 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4670 {
4671 /* As an extension, allow initializing objects with static storage
4672 duration with compound literals (which are then treated just as
4673 the brace enclosed list they contain). Also allow this for
4674 vectors, as we can only assign them with compound literals. */
4675 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4676 inside_init = DECL_INITIAL (decl);
4677 }
4678
4679 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4680 && TREE_CODE (inside_init) != CONSTRUCTOR)
4681 {
4682 error_init ("array initialized from non-constant array expression");
4683 return error_mark_node;
4684 }
4685
4686 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4687 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4688
4689 /* Compound expressions can only occur here if -pedantic or
4690 -pedantic-errors is specified. In the later case, we always want
4691 an error. In the former case, we simply want a warning. */
4692 if (require_constant && pedantic
4693 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4694 {
4695 inside_init
4696 = valid_compound_expr_initializer (inside_init,
4697 TREE_TYPE (inside_init));
4698 if (inside_init == error_mark_node)
4699 error_init ("initializer element is not constant");
4700 else
4701 pedwarn_init ("initializer element is not constant");
4702 if (flag_pedantic_errors)
4703 inside_init = error_mark_node;
4704 }
4705 else if (require_constant
4706 && !initializer_constant_valid_p (inside_init,
4707 TREE_TYPE (inside_init)))
4708 {
4709 error_init ("initializer element is not constant");
4710 inside_init = error_mark_node;
4711 }
4712
4713 /* Added to enable additional -Wmissing-format-attribute warnings. */
4714 if (TREE_CODE (TREE_TYPE (inside_init)) == POINTER_TYPE)
4715 inside_init = convert_for_assignment (type, inside_init, ic_init, NULL_TREE,
4716 NULL_TREE, 0);
4717 return inside_init;
4718 }
4719
4720 /* Handle scalar types, including conversions. */
4721
4722 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4723 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
4724 || code == VECTOR_TYPE)
4725 {
4726 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE
4727 && (TREE_CODE (init) == STRING_CST
4728 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR))
4729 init = array_to_pointer_conversion (init);
4730 inside_init
4731 = convert_for_assignment (type, init, ic_init,
4732 NULL_TREE, NULL_TREE, 0);
4733
4734 /* Check to see if we have already given an error message. */
4735 if (inside_init == error_mark_node)
4736 ;
4737 else if (require_constant && !TREE_CONSTANT (inside_init))
4738 {
4739 error_init ("initializer element is not constant");
4740 inside_init = error_mark_node;
4741 }
4742 else if (require_constant
4743 && !initializer_constant_valid_p (inside_init,
4744 TREE_TYPE (inside_init)))
4745 {
4746 error_init ("initializer element is not computable at load time");
4747 inside_init = error_mark_node;
4748 }
4749
4750 return inside_init;
4751 }
4752
4753 /* Come here only for records and arrays. */
4754
4755 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4756 {
4757 error_init ("variable-sized object may not be initialized");
4758 return error_mark_node;
4759 }
4760
4761 error_init ("invalid initializer");
4762 return error_mark_node;
4763 }
4764 \f
4765 /* Handle initializers that use braces. */
4766
4767 /* Type of object we are accumulating a constructor for.
4768 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4769 static tree constructor_type;
4770
4771 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4772 left to fill. */
4773 static tree constructor_fields;
4774
4775 /* For an ARRAY_TYPE, this is the specified index
4776 at which to store the next element we get. */
4777 static tree constructor_index;
4778
4779 /* For an ARRAY_TYPE, this is the maximum index. */
4780 static tree constructor_max_index;
4781
4782 /* For a RECORD_TYPE, this is the first field not yet written out. */
4783 static tree constructor_unfilled_fields;
4784
4785 /* For an ARRAY_TYPE, this is the index of the first element
4786 not yet written out. */
4787 static tree constructor_unfilled_index;
4788
4789 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4790 This is so we can generate gaps between fields, when appropriate. */
4791 static tree constructor_bit_index;
4792
4793 /* If we are saving up the elements rather than allocating them,
4794 this is the list of elements so far (in reverse order,
4795 most recent first). */
4796 static VEC(constructor_elt,gc) *constructor_elements;
4797
4798 /* 1 if constructor should be incrementally stored into a constructor chain,
4799 0 if all the elements should be kept in AVL tree. */
4800 static int constructor_incremental;
4801
4802 /* 1 if so far this constructor's elements are all compile-time constants. */
4803 static int constructor_constant;
4804
4805 /* 1 if so far this constructor's elements are all valid address constants. */
4806 static int constructor_simple;
4807
4808 /* 1 if this constructor is erroneous so far. */
4809 static int constructor_erroneous;
4810
4811 /* Structure for managing pending initializer elements, organized as an
4812 AVL tree. */
4813
4814 struct init_node
4815 {
4816 struct init_node *left, *right;
4817 struct init_node *parent;
4818 int balance;
4819 tree purpose;
4820 tree value;
4821 };
4822
4823 /* Tree of pending elements at this constructor level.
4824 These are elements encountered out of order
4825 which belong at places we haven't reached yet in actually
4826 writing the output.
4827 Will never hold tree nodes across GC runs. */
4828 static struct init_node *constructor_pending_elts;
4829
4830 /* The SPELLING_DEPTH of this constructor. */
4831 static int constructor_depth;
4832
4833 /* DECL node for which an initializer is being read.
4834 0 means we are reading a constructor expression
4835 such as (struct foo) {...}. */
4836 static tree constructor_decl;
4837
4838 /* Nonzero if this is an initializer for a top-level decl. */
4839 static int constructor_top_level;
4840
4841 /* Nonzero if there were any member designators in this initializer. */
4842 static int constructor_designated;
4843
4844 /* Nesting depth of designator list. */
4845 static int designator_depth;
4846
4847 /* Nonzero if there were diagnosed errors in this designator list. */
4848 static int designator_erroneous;
4849
4850 \f
4851 /* This stack has a level for each implicit or explicit level of
4852 structuring in the initializer, including the outermost one. It
4853 saves the values of most of the variables above. */
4854
4855 struct constructor_range_stack;
4856
4857 struct constructor_stack
4858 {
4859 struct constructor_stack *next;
4860 tree type;
4861 tree fields;
4862 tree index;
4863 tree max_index;
4864 tree unfilled_index;
4865 tree unfilled_fields;
4866 tree bit_index;
4867 VEC(constructor_elt,gc) *elements;
4868 struct init_node *pending_elts;
4869 int offset;
4870 int depth;
4871 /* If value nonzero, this value should replace the entire
4872 constructor at this level. */
4873 struct c_expr replacement_value;
4874 struct constructor_range_stack *range_stack;
4875 char constant;
4876 char simple;
4877 char implicit;
4878 char erroneous;
4879 char outer;
4880 char incremental;
4881 char designated;
4882 };
4883
4884 static struct constructor_stack *constructor_stack;
4885
4886 /* This stack represents designators from some range designator up to
4887 the last designator in the list. */
4888
4889 struct constructor_range_stack
4890 {
4891 struct constructor_range_stack *next, *prev;
4892 struct constructor_stack *stack;
4893 tree range_start;
4894 tree index;
4895 tree range_end;
4896 tree fields;
4897 };
4898
4899 static struct constructor_range_stack *constructor_range_stack;
4900
4901 /* This stack records separate initializers that are nested.
4902 Nested initializers can't happen in ANSI C, but GNU C allows them
4903 in cases like { ... (struct foo) { ... } ... }. */
4904
4905 struct initializer_stack
4906 {
4907 struct initializer_stack *next;
4908 tree decl;
4909 struct constructor_stack *constructor_stack;
4910 struct constructor_range_stack *constructor_range_stack;
4911 VEC(constructor_elt,gc) *elements;
4912 struct spelling *spelling;
4913 struct spelling *spelling_base;
4914 int spelling_size;
4915 char top_level;
4916 char require_constant_value;
4917 char require_constant_elements;
4918 };
4919
4920 static struct initializer_stack *initializer_stack;
4921 \f
4922 /* Prepare to parse and output the initializer for variable DECL. */
4923
4924 void
4925 start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
4926 {
4927 const char *locus;
4928 struct initializer_stack *p = XNEW (struct initializer_stack);
4929
4930 p->decl = constructor_decl;
4931 p->require_constant_value = require_constant_value;
4932 p->require_constant_elements = require_constant_elements;
4933 p->constructor_stack = constructor_stack;
4934 p->constructor_range_stack = constructor_range_stack;
4935 p->elements = constructor_elements;
4936 p->spelling = spelling;
4937 p->spelling_base = spelling_base;
4938 p->spelling_size = spelling_size;
4939 p->top_level = constructor_top_level;
4940 p->next = initializer_stack;
4941 initializer_stack = p;
4942
4943 constructor_decl = decl;
4944 constructor_designated = 0;
4945 constructor_top_level = top_level;
4946
4947 if (decl != 0 && decl != error_mark_node)
4948 {
4949 require_constant_value = TREE_STATIC (decl);
4950 require_constant_elements
4951 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
4952 /* For a scalar, you can always use any value to initialize,
4953 even within braces. */
4954 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4955 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4956 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4957 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4958 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4959 }
4960 else
4961 {
4962 require_constant_value = 0;
4963 require_constant_elements = 0;
4964 locus = "(anonymous)";
4965 }
4966
4967 constructor_stack = 0;
4968 constructor_range_stack = 0;
4969
4970 missing_braces_mentioned = 0;
4971
4972 spelling_base = 0;
4973 spelling_size = 0;
4974 RESTORE_SPELLING_DEPTH (0);
4975
4976 if (locus)
4977 push_string (locus);
4978 }
4979
4980 void
4981 finish_init (void)
4982 {
4983 struct initializer_stack *p = initializer_stack;
4984
4985 /* Free the whole constructor stack of this initializer. */
4986 while (constructor_stack)
4987 {
4988 struct constructor_stack *q = constructor_stack;
4989 constructor_stack = q->next;
4990 free (q);
4991 }
4992
4993 gcc_assert (!constructor_range_stack);
4994
4995 /* Pop back to the data of the outer initializer (if any). */
4996 free (spelling_base);
4997
4998 constructor_decl = p->decl;
4999 require_constant_value = p->require_constant_value;
5000 require_constant_elements = p->require_constant_elements;
5001 constructor_stack = p->constructor_stack;
5002 constructor_range_stack = p->constructor_range_stack;
5003 constructor_elements = p->elements;
5004 spelling = p->spelling;
5005 spelling_base = p->spelling_base;
5006 spelling_size = p->spelling_size;
5007 constructor_top_level = p->top_level;
5008 initializer_stack = p->next;
5009 free (p);
5010 }
5011 \f
5012 /* Call here when we see the initializer is surrounded by braces.
5013 This is instead of a call to push_init_level;
5014 it is matched by a call to pop_init_level.
5015
5016 TYPE is the type to initialize, for a constructor expression.
5017 For an initializer for a decl, TYPE is zero. */
5018
5019 void
5020 really_start_incremental_init (tree type)
5021 {
5022 struct constructor_stack *p = XNEW (struct constructor_stack);
5023
5024 if (type == 0)
5025 type = TREE_TYPE (constructor_decl);
5026
5027 if (targetm.vector_opaque_p (type))
5028 error ("opaque vector types cannot be initialized");
5029
5030 p->type = constructor_type;
5031 p->fields = constructor_fields;
5032 p->index = constructor_index;
5033 p->max_index = constructor_max_index;
5034 p->unfilled_index = constructor_unfilled_index;
5035 p->unfilled_fields = constructor_unfilled_fields;
5036 p->bit_index = constructor_bit_index;
5037 p->elements = constructor_elements;
5038 p->constant = constructor_constant;
5039 p->simple = constructor_simple;
5040 p->erroneous = constructor_erroneous;
5041 p->pending_elts = constructor_pending_elts;
5042 p->depth = constructor_depth;
5043 p->replacement_value.value = 0;
5044 p->replacement_value.original_code = ERROR_MARK;
5045 p->implicit = 0;
5046 p->range_stack = 0;
5047 p->outer = 0;
5048 p->incremental = constructor_incremental;
5049 p->designated = constructor_designated;
5050 p->next = 0;
5051 constructor_stack = p;
5052
5053 constructor_constant = 1;
5054 constructor_simple = 1;
5055 constructor_depth = SPELLING_DEPTH ();
5056 constructor_elements = 0;
5057 constructor_pending_elts = 0;
5058 constructor_type = type;
5059 constructor_incremental = 1;
5060 constructor_designated = 0;
5061 designator_depth = 0;
5062 designator_erroneous = 0;
5063
5064 if (TREE_CODE (constructor_type) == RECORD_TYPE
5065 || TREE_CODE (constructor_type) == UNION_TYPE)
5066 {
5067 constructor_fields = TYPE_FIELDS (constructor_type);
5068 /* Skip any nameless bit fields at the beginning. */
5069 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5070 && DECL_NAME (constructor_fields) == 0)
5071 constructor_fields = TREE_CHAIN (constructor_fields);
5072
5073 constructor_unfilled_fields = constructor_fields;
5074 constructor_bit_index = bitsize_zero_node;
5075 }
5076 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5077 {
5078 if (TYPE_DOMAIN (constructor_type))
5079 {
5080 constructor_max_index
5081 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5082
5083 /* Detect non-empty initializations of zero-length arrays. */
5084 if (constructor_max_index == NULL_TREE
5085 && TYPE_SIZE (constructor_type))
5086 constructor_max_index = build_int_cst (NULL_TREE, -1);
5087
5088 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5089 to initialize VLAs will cause a proper error; avoid tree
5090 checking errors as well by setting a safe value. */
5091 if (constructor_max_index
5092 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5093 constructor_max_index = build_int_cst (NULL_TREE, -1);
5094
5095 constructor_index
5096 = convert (bitsizetype,
5097 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5098 }
5099 else
5100 {
5101 constructor_index = bitsize_zero_node;
5102 constructor_max_index = NULL_TREE;
5103 }
5104
5105 constructor_unfilled_index = constructor_index;
5106 }
5107 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5108 {
5109 /* Vectors are like simple fixed-size arrays. */
5110 constructor_max_index =
5111 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5112 constructor_index = bitsize_zero_node;
5113 constructor_unfilled_index = constructor_index;
5114 }
5115 else
5116 {
5117 /* Handle the case of int x = {5}; */
5118 constructor_fields = constructor_type;
5119 constructor_unfilled_fields = constructor_type;
5120 }
5121 }
5122 \f
5123 /* Push down into a subobject, for initialization.
5124 If this is for an explicit set of braces, IMPLICIT is 0.
5125 If it is because the next element belongs at a lower level,
5126 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5127
5128 void
5129 push_init_level (int implicit)
5130 {
5131 struct constructor_stack *p;
5132 tree value = NULL_TREE;
5133
5134 /* If we've exhausted any levels that didn't have braces,
5135 pop them now. If implicit == 1, this will have been done in
5136 process_init_element; do not repeat it here because in the case
5137 of excess initializers for an empty aggregate this leads to an
5138 infinite cycle of popping a level and immediately recreating
5139 it. */
5140 if (implicit != 1)
5141 {
5142 while (constructor_stack->implicit)
5143 {
5144 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5145 || TREE_CODE (constructor_type) == UNION_TYPE)
5146 && constructor_fields == 0)
5147 process_init_element (pop_init_level (1));
5148 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5149 && constructor_max_index
5150 && tree_int_cst_lt (constructor_max_index,
5151 constructor_index))
5152 process_init_element (pop_init_level (1));
5153 else
5154 break;
5155 }
5156 }
5157
5158 /* Unless this is an explicit brace, we need to preserve previous
5159 content if any. */
5160 if (implicit)
5161 {
5162 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5163 || TREE_CODE (constructor_type) == UNION_TYPE)
5164 && constructor_fields)
5165 value = find_init_member (constructor_fields);
5166 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5167 value = find_init_member (constructor_index);
5168 }
5169
5170 p = XNEW (struct constructor_stack);
5171 p->type = constructor_type;
5172 p->fields = constructor_fields;
5173 p->index = constructor_index;
5174 p->max_index = constructor_max_index;
5175 p->unfilled_index = constructor_unfilled_index;
5176 p->unfilled_fields = constructor_unfilled_fields;
5177 p->bit_index = constructor_bit_index;
5178 p->elements = constructor_elements;
5179 p->constant = constructor_constant;
5180 p->simple = constructor_simple;
5181 p->erroneous = constructor_erroneous;
5182 p->pending_elts = constructor_pending_elts;
5183 p->depth = constructor_depth;
5184 p->replacement_value.value = 0;
5185 p->replacement_value.original_code = ERROR_MARK;
5186 p->implicit = implicit;
5187 p->outer = 0;
5188 p->incremental = constructor_incremental;
5189 p->designated = constructor_designated;
5190 p->next = constructor_stack;
5191 p->range_stack = 0;
5192 constructor_stack = p;
5193
5194 constructor_constant = 1;
5195 constructor_simple = 1;
5196 constructor_depth = SPELLING_DEPTH ();
5197 constructor_elements = 0;
5198 constructor_incremental = 1;
5199 constructor_designated = 0;
5200 constructor_pending_elts = 0;
5201 if (!implicit)
5202 {
5203 p->range_stack = constructor_range_stack;
5204 constructor_range_stack = 0;
5205 designator_depth = 0;
5206 designator_erroneous = 0;
5207 }
5208
5209 /* Don't die if an entire brace-pair level is superfluous
5210 in the containing level. */
5211 if (constructor_type == 0)
5212 ;
5213 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5214 || TREE_CODE (constructor_type) == UNION_TYPE)
5215 {
5216 /* Don't die if there are extra init elts at the end. */
5217 if (constructor_fields == 0)
5218 constructor_type = 0;
5219 else
5220 {
5221 constructor_type = TREE_TYPE (constructor_fields);
5222 push_member_name (constructor_fields);
5223 constructor_depth++;
5224 }
5225 }
5226 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5227 {
5228 constructor_type = TREE_TYPE (constructor_type);
5229 push_array_bounds (tree_low_cst (constructor_index, 1));
5230 constructor_depth++;
5231 }
5232
5233 if (constructor_type == 0)
5234 {
5235 error_init ("extra brace group at end of initializer");
5236 constructor_fields = 0;
5237 constructor_unfilled_fields = 0;
5238 return;
5239 }
5240
5241 if (value && TREE_CODE (value) == CONSTRUCTOR)
5242 {
5243 constructor_constant = TREE_CONSTANT (value);
5244 constructor_simple = TREE_STATIC (value);
5245 constructor_elements = CONSTRUCTOR_ELTS (value);
5246 if (!VEC_empty (constructor_elt, constructor_elements)
5247 && (TREE_CODE (constructor_type) == RECORD_TYPE
5248 || TREE_CODE (constructor_type) == ARRAY_TYPE))
5249 set_nonincremental_init ();
5250 }
5251
5252 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
5253 {
5254 missing_braces_mentioned = 1;
5255 warning_init ("missing braces around initializer");
5256 }
5257
5258 if (TREE_CODE (constructor_type) == RECORD_TYPE
5259 || TREE_CODE (constructor_type) == UNION_TYPE)
5260 {
5261 constructor_fields = TYPE_FIELDS (constructor_type);
5262 /* Skip any nameless bit fields at the beginning. */
5263 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5264 && DECL_NAME (constructor_fields) == 0)
5265 constructor_fields = TREE_CHAIN (constructor_fields);
5266
5267 constructor_unfilled_fields = constructor_fields;
5268 constructor_bit_index = bitsize_zero_node;
5269 }
5270 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5271 {
5272 /* Vectors are like simple fixed-size arrays. */
5273 constructor_max_index =
5274 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5275 constructor_index = convert (bitsizetype, integer_zero_node);
5276 constructor_unfilled_index = constructor_index;
5277 }
5278 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5279 {
5280 if (TYPE_DOMAIN (constructor_type))
5281 {
5282 constructor_max_index
5283 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5284
5285 /* Detect non-empty initializations of zero-length arrays. */
5286 if (constructor_max_index == NULL_TREE
5287 && TYPE_SIZE (constructor_type))
5288 constructor_max_index = build_int_cst (NULL_TREE, -1);
5289
5290 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5291 to initialize VLAs will cause a proper error; avoid tree
5292 checking errors as well by setting a safe value. */
5293 if (constructor_max_index
5294 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5295 constructor_max_index = build_int_cst (NULL_TREE, -1);
5296
5297 constructor_index
5298 = convert (bitsizetype,
5299 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5300 }
5301 else
5302 constructor_index = bitsize_zero_node;
5303
5304 constructor_unfilled_index = constructor_index;
5305 if (value && TREE_CODE (value) == STRING_CST)
5306 {
5307 /* We need to split the char/wchar array into individual
5308 characters, so that we don't have to special case it
5309 everywhere. */
5310 set_nonincremental_init_from_string (value);
5311 }
5312 }
5313 else
5314 {
5315 if (constructor_type != error_mark_node)
5316 warning_init ("braces around scalar initializer");
5317 constructor_fields = constructor_type;
5318 constructor_unfilled_fields = constructor_type;
5319 }
5320 }
5321
5322 /* At the end of an implicit or explicit brace level,
5323 finish up that level of constructor. If a single expression
5324 with redundant braces initialized that level, return the
5325 c_expr structure for that expression. Otherwise, the original_code
5326 element is set to ERROR_MARK.
5327 If we were outputting the elements as they are read, return 0 as the value
5328 from inner levels (process_init_element ignores that),
5329 but return error_mark_node as the value from the outermost level
5330 (that's what we want to put in DECL_INITIAL).
5331 Otherwise, return a CONSTRUCTOR expression as the value. */
5332
5333 struct c_expr
5334 pop_init_level (int implicit)
5335 {
5336 struct constructor_stack *p;
5337 struct c_expr ret;
5338 ret.value = 0;
5339 ret.original_code = ERROR_MARK;
5340
5341 if (implicit == 0)
5342 {
5343 /* When we come to an explicit close brace,
5344 pop any inner levels that didn't have explicit braces. */
5345 while (constructor_stack->implicit)
5346 process_init_element (pop_init_level (1));
5347
5348 gcc_assert (!constructor_range_stack);
5349 }
5350
5351 /* Now output all pending elements. */
5352 constructor_incremental = 1;
5353 output_pending_init_elements (1);
5354
5355 p = constructor_stack;
5356
5357 /* Error for initializing a flexible array member, or a zero-length
5358 array member in an inappropriate context. */
5359 if (constructor_type && constructor_fields
5360 && TREE_CODE (constructor_type) == ARRAY_TYPE
5361 && TYPE_DOMAIN (constructor_type)
5362 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5363 {
5364 /* Silently discard empty initializations. The parser will
5365 already have pedwarned for empty brackets. */
5366 if (integer_zerop (constructor_unfilled_index))
5367 constructor_type = NULL_TREE;
5368 else
5369 {
5370 gcc_assert (!TYPE_SIZE (constructor_type));
5371
5372 if (constructor_depth > 2)
5373 error_init ("initialization of flexible array member in a nested context");
5374 else if (pedantic)
5375 pedwarn_init ("initialization of a flexible array member");
5376
5377 /* We have already issued an error message for the existence
5378 of a flexible array member not at the end of the structure.
5379 Discard the initializer so that we do not die later. */
5380 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
5381 constructor_type = NULL_TREE;
5382 }
5383 }
5384
5385 /* Warn when some struct elements are implicitly initialized to zero. */
5386 if (warn_missing_field_initializers
5387 && constructor_type
5388 && TREE_CODE (constructor_type) == RECORD_TYPE
5389 && constructor_unfilled_fields)
5390 {
5391 /* Do not warn for flexible array members or zero-length arrays. */
5392 while (constructor_unfilled_fields
5393 && (!DECL_SIZE (constructor_unfilled_fields)
5394 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
5395 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5396
5397 /* Do not warn if this level of the initializer uses member
5398 designators; it is likely to be deliberate. */
5399 if (constructor_unfilled_fields && !constructor_designated)
5400 {
5401 push_member_name (constructor_unfilled_fields);
5402 warning_init ("missing initializer");
5403 RESTORE_SPELLING_DEPTH (constructor_depth);
5404 }
5405 }
5406
5407 /* Pad out the end of the structure. */
5408 if (p->replacement_value.value)
5409 /* If this closes a superfluous brace pair,
5410 just pass out the element between them. */
5411 ret = p->replacement_value;
5412 else if (constructor_type == 0)
5413 ;
5414 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5415 && TREE_CODE (constructor_type) != UNION_TYPE
5416 && TREE_CODE (constructor_type) != ARRAY_TYPE
5417 && TREE_CODE (constructor_type) != VECTOR_TYPE)
5418 {
5419 /* A nonincremental scalar initializer--just return
5420 the element, after verifying there is just one. */
5421 if (VEC_empty (constructor_elt,constructor_elements))
5422 {
5423 if (!constructor_erroneous)
5424 error_init ("empty scalar initializer");
5425 ret.value = error_mark_node;
5426 }
5427 else if (VEC_length (constructor_elt,constructor_elements) != 1)
5428 {
5429 error_init ("extra elements in scalar initializer");
5430 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
5431 }
5432 else
5433 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
5434 }
5435 else
5436 {
5437 if (constructor_erroneous)
5438 ret.value = error_mark_node;
5439 else
5440 {
5441 ret.value = build_constructor (constructor_type,
5442 constructor_elements);
5443 if (constructor_constant)
5444 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1;
5445 if (constructor_constant && constructor_simple)
5446 TREE_STATIC (ret.value) = 1;
5447 }
5448 }
5449
5450 constructor_type = p->type;
5451 constructor_fields = p->fields;
5452 constructor_index = p->index;
5453 constructor_max_index = p->max_index;
5454 constructor_unfilled_index = p->unfilled_index;
5455 constructor_unfilled_fields = p->unfilled_fields;
5456 constructor_bit_index = p->bit_index;
5457 constructor_elements = p->elements;
5458 constructor_constant = p->constant;
5459 constructor_simple = p->simple;
5460 constructor_erroneous = p->erroneous;
5461 constructor_incremental = p->incremental;
5462 constructor_designated = p->designated;
5463 constructor_pending_elts = p->pending_elts;
5464 constructor_depth = p->depth;
5465 if (!p->implicit)
5466 constructor_range_stack = p->range_stack;
5467 RESTORE_SPELLING_DEPTH (constructor_depth);
5468
5469 constructor_stack = p->next;
5470 free (p);
5471
5472 if (ret.value == 0 && constructor_stack == 0)
5473 ret.value = error_mark_node;
5474 return ret;
5475 }
5476
5477 /* Common handling for both array range and field name designators.
5478 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5479
5480 static int
5481 set_designator (int array)
5482 {
5483 tree subtype;
5484 enum tree_code subcode;
5485
5486 /* Don't die if an entire brace-pair level is superfluous
5487 in the containing level. */
5488 if (constructor_type == 0)
5489 return 1;
5490
5491 /* If there were errors in this designator list already, bail out
5492 silently. */
5493 if (designator_erroneous)
5494 return 1;
5495
5496 if (!designator_depth)
5497 {
5498 gcc_assert (!constructor_range_stack);
5499
5500 /* Designator list starts at the level of closest explicit
5501 braces. */
5502 while (constructor_stack->implicit)
5503 process_init_element (pop_init_level (1));
5504 constructor_designated = 1;
5505 return 0;
5506 }
5507
5508 switch (TREE_CODE (constructor_type))
5509 {
5510 case RECORD_TYPE:
5511 case UNION_TYPE:
5512 subtype = TREE_TYPE (constructor_fields);
5513 if (subtype != error_mark_node)
5514 subtype = TYPE_MAIN_VARIANT (subtype);
5515 break;
5516 case ARRAY_TYPE:
5517 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5518 break;
5519 default:
5520 gcc_unreachable ();
5521 }
5522
5523 subcode = TREE_CODE (subtype);
5524 if (array && subcode != ARRAY_TYPE)
5525 {
5526 error_init ("array index in non-array initializer");
5527 return 1;
5528 }
5529 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
5530 {
5531 error_init ("field name not in record or union initializer");
5532 return 1;
5533 }
5534
5535 constructor_designated = 1;
5536 push_init_level (2);
5537 return 0;
5538 }
5539
5540 /* If there are range designators in designator list, push a new designator
5541 to constructor_range_stack. RANGE_END is end of such stack range or
5542 NULL_TREE if there is no range designator at this level. */
5543
5544 static void
5545 push_range_stack (tree range_end)
5546 {
5547 struct constructor_range_stack *p;
5548
5549 p = GGC_NEW (struct constructor_range_stack);
5550 p->prev = constructor_range_stack;
5551 p->next = 0;
5552 p->fields = constructor_fields;
5553 p->range_start = constructor_index;
5554 p->index = constructor_index;
5555 p->stack = constructor_stack;
5556 p->range_end = range_end;
5557 if (constructor_range_stack)
5558 constructor_range_stack->next = p;
5559 constructor_range_stack = p;
5560 }
5561
5562 /* Within an array initializer, specify the next index to be initialized.
5563 FIRST is that index. If LAST is nonzero, then initialize a range
5564 of indices, running from FIRST through LAST. */
5565
5566 void
5567 set_init_index (tree first, tree last)
5568 {
5569 if (set_designator (1))
5570 return;
5571
5572 designator_erroneous = 1;
5573
5574 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
5575 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
5576 {
5577 error_init ("array index in initializer not of integer type");
5578 return;
5579 }
5580
5581 if (TREE_CODE (first) != INTEGER_CST)
5582 error_init ("nonconstant array index in initializer");
5583 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5584 error_init ("nonconstant array index in initializer");
5585 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5586 error_init ("array index in non-array initializer");
5587 else if (tree_int_cst_sgn (first) == -1)
5588 error_init ("array index in initializer exceeds array bounds");
5589 else if (constructor_max_index
5590 && tree_int_cst_lt (constructor_max_index, first))
5591 error_init ("array index in initializer exceeds array bounds");
5592 else
5593 {
5594 constructor_index = convert (bitsizetype, first);
5595
5596 if (last)
5597 {
5598 if (tree_int_cst_equal (first, last))
5599 last = 0;
5600 else if (tree_int_cst_lt (last, first))
5601 {
5602 error_init ("empty index range in initializer");
5603 last = 0;
5604 }
5605 else
5606 {
5607 last = convert (bitsizetype, last);
5608 if (constructor_max_index != 0
5609 && tree_int_cst_lt (constructor_max_index, last))
5610 {
5611 error_init ("array index range in initializer exceeds array bounds");
5612 last = 0;
5613 }
5614 }
5615 }
5616
5617 designator_depth++;
5618 designator_erroneous = 0;
5619 if (constructor_range_stack || last)
5620 push_range_stack (last);
5621 }
5622 }
5623
5624 /* Within a struct initializer, specify the next field to be initialized. */
5625
5626 void
5627 set_init_label (tree fieldname)
5628 {
5629 tree tail;
5630
5631 if (set_designator (0))
5632 return;
5633
5634 designator_erroneous = 1;
5635
5636 if (TREE_CODE (constructor_type) != RECORD_TYPE
5637 && TREE_CODE (constructor_type) != UNION_TYPE)
5638 {
5639 error_init ("field name not in record or union initializer");
5640 return;
5641 }
5642
5643 for (tail = TYPE_FIELDS (constructor_type); tail;
5644 tail = TREE_CHAIN (tail))
5645 {
5646 if (DECL_NAME (tail) == fieldname)
5647 break;
5648 }
5649
5650 if (tail == 0)
5651 error ("unknown field %qE specified in initializer", fieldname);
5652 else
5653 {
5654 constructor_fields = tail;
5655 designator_depth++;
5656 designator_erroneous = 0;
5657 if (constructor_range_stack)
5658 push_range_stack (NULL_TREE);
5659 }
5660 }
5661 \f
5662 /* Add a new initializer to the tree of pending initializers. PURPOSE
5663 identifies the initializer, either array index or field in a structure.
5664 VALUE is the value of that index or field. */
5665
5666 static void
5667 add_pending_init (tree purpose, tree value)
5668 {
5669 struct init_node *p, **q, *r;
5670
5671 q = &constructor_pending_elts;
5672 p = 0;
5673
5674 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5675 {
5676 while (*q != 0)
5677 {
5678 p = *q;
5679 if (tree_int_cst_lt (purpose, p->purpose))
5680 q = &p->left;
5681 else if (tree_int_cst_lt (p->purpose, purpose))
5682 q = &p->right;
5683 else
5684 {
5685 if (TREE_SIDE_EFFECTS (p->value))
5686 warning_init ("initialized field with side-effects overwritten");
5687 else if (warn_override_init)
5688 warning_init ("initialized field overwritten");
5689 p->value = value;
5690 return;
5691 }
5692 }
5693 }
5694 else
5695 {
5696 tree bitpos;
5697
5698 bitpos = bit_position (purpose);
5699 while (*q != NULL)
5700 {
5701 p = *q;
5702 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5703 q = &p->left;
5704 else if (p->purpose != purpose)
5705 q = &p->right;
5706 else
5707 {
5708 if (TREE_SIDE_EFFECTS (p->value))
5709 warning_init ("initialized field with side-effects overwritten");
5710 else if (warn_override_init)
5711 warning_init ("initialized field overwritten");
5712 p->value = value;
5713 return;
5714 }
5715 }
5716 }
5717
5718 r = GGC_NEW (struct init_node);
5719 r->purpose = purpose;
5720 r->value = value;
5721
5722 *q = r;
5723 r->parent = p;
5724 r->left = 0;
5725 r->right = 0;
5726 r->balance = 0;
5727
5728 while (p)
5729 {
5730 struct init_node *s;
5731
5732 if (r == p->left)
5733 {
5734 if (p->balance == 0)
5735 p->balance = -1;
5736 else if (p->balance < 0)
5737 {
5738 if (r->balance < 0)
5739 {
5740 /* L rotation. */
5741 p->left = r->right;
5742 if (p->left)
5743 p->left->parent = p;
5744 r->right = p;
5745
5746 p->balance = 0;
5747 r->balance = 0;
5748
5749 s = p->parent;
5750 p->parent = r;
5751 r->parent = s;
5752 if (s)
5753 {
5754 if (s->left == p)
5755 s->left = r;
5756 else
5757 s->right = r;
5758 }
5759 else
5760 constructor_pending_elts = r;
5761 }
5762 else
5763 {
5764 /* LR rotation. */
5765 struct init_node *t = r->right;
5766
5767 r->right = t->left;
5768 if (r->right)
5769 r->right->parent = r;
5770 t->left = r;
5771
5772 p->left = t->right;
5773 if (p->left)
5774 p->left->parent = p;
5775 t->right = p;
5776
5777 p->balance = t->balance < 0;
5778 r->balance = -(t->balance > 0);
5779 t->balance = 0;
5780
5781 s = p->parent;
5782 p->parent = t;
5783 r->parent = t;
5784 t->parent = s;
5785 if (s)
5786 {
5787 if (s->left == p)
5788 s->left = t;
5789 else
5790 s->right = t;
5791 }
5792 else
5793 constructor_pending_elts = t;
5794 }
5795 break;
5796 }
5797 else
5798 {
5799 /* p->balance == +1; growth of left side balances the node. */
5800 p->balance = 0;
5801 break;
5802 }
5803 }
5804 else /* r == p->right */
5805 {
5806 if (p->balance == 0)
5807 /* Growth propagation from right side. */
5808 p->balance++;
5809 else if (p->balance > 0)
5810 {
5811 if (r->balance > 0)
5812 {
5813 /* R rotation. */
5814 p->right = r->left;
5815 if (p->right)
5816 p->right->parent = p;
5817 r->left = p;
5818
5819 p->balance = 0;
5820 r->balance = 0;
5821
5822 s = p->parent;
5823 p->parent = r;
5824 r->parent = s;
5825 if (s)
5826 {
5827 if (s->left == p)
5828 s->left = r;
5829 else
5830 s->right = r;
5831 }
5832 else
5833 constructor_pending_elts = r;
5834 }
5835 else /* r->balance == -1 */
5836 {
5837 /* RL rotation */
5838 struct init_node *t = r->left;
5839
5840 r->left = t->right;
5841 if (r->left)
5842 r->left->parent = r;
5843 t->right = r;
5844
5845 p->right = t->left;
5846 if (p->right)
5847 p->right->parent = p;
5848 t->left = p;
5849
5850 r->balance = (t->balance < 0);
5851 p->balance = -(t->balance > 0);
5852 t->balance = 0;
5853
5854 s = p->parent;
5855 p->parent = t;
5856 r->parent = t;
5857 t->parent = s;
5858 if (s)
5859 {
5860 if (s->left == p)
5861 s->left = t;
5862 else
5863 s->right = t;
5864 }
5865 else
5866 constructor_pending_elts = t;
5867 }
5868 break;
5869 }
5870 else
5871 {
5872 /* p->balance == -1; growth of right side balances the node. */
5873 p->balance = 0;
5874 break;
5875 }
5876 }
5877
5878 r = p;
5879 p = p->parent;
5880 }
5881 }
5882
5883 /* Build AVL tree from a sorted chain. */
5884
5885 static void
5886 set_nonincremental_init (void)
5887 {
5888 unsigned HOST_WIDE_INT ix;
5889 tree index, value;
5890
5891 if (TREE_CODE (constructor_type) != RECORD_TYPE
5892 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5893 return;
5894
5895 FOR_EACH_CONSTRUCTOR_ELT (constructor_elements, ix, index, value)
5896 add_pending_init (index, value);
5897 constructor_elements = 0;
5898 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5899 {
5900 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
5901 /* Skip any nameless bit fields at the beginning. */
5902 while (constructor_unfilled_fields != 0
5903 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5904 && DECL_NAME (constructor_unfilled_fields) == 0)
5905 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5906
5907 }
5908 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5909 {
5910 if (TYPE_DOMAIN (constructor_type))
5911 constructor_unfilled_index
5912 = convert (bitsizetype,
5913 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5914 else
5915 constructor_unfilled_index = bitsize_zero_node;
5916 }
5917 constructor_incremental = 0;
5918 }
5919
5920 /* Build AVL tree from a string constant. */
5921
5922 static void
5923 set_nonincremental_init_from_string (tree str)
5924 {
5925 tree value, purpose, type;
5926 HOST_WIDE_INT val[2];
5927 const char *p, *end;
5928 int byte, wchar_bytes, charwidth, bitpos;
5929
5930 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
5931
5932 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5933 == TYPE_PRECISION (char_type_node))
5934 wchar_bytes = 1;
5935 else
5936 {
5937 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5938 == TYPE_PRECISION (wchar_type_node));
5939 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
5940 }
5941 charwidth = TYPE_PRECISION (char_type_node);
5942 type = TREE_TYPE (constructor_type);
5943 p = TREE_STRING_POINTER (str);
5944 end = p + TREE_STRING_LENGTH (str);
5945
5946 for (purpose = bitsize_zero_node;
5947 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
5948 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
5949 {
5950 if (wchar_bytes == 1)
5951 {
5952 val[1] = (unsigned char) *p++;
5953 val[0] = 0;
5954 }
5955 else
5956 {
5957 val[0] = 0;
5958 val[1] = 0;
5959 for (byte = 0; byte < wchar_bytes; byte++)
5960 {
5961 if (BYTES_BIG_ENDIAN)
5962 bitpos = (wchar_bytes - byte - 1) * charwidth;
5963 else
5964 bitpos = byte * charwidth;
5965 val[bitpos < HOST_BITS_PER_WIDE_INT]
5966 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
5967 << (bitpos % HOST_BITS_PER_WIDE_INT);
5968 }
5969 }
5970
5971 if (!TYPE_UNSIGNED (type))
5972 {
5973 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
5974 if (bitpos < HOST_BITS_PER_WIDE_INT)
5975 {
5976 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
5977 {
5978 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
5979 val[0] = -1;
5980 }
5981 }
5982 else if (bitpos == HOST_BITS_PER_WIDE_INT)
5983 {
5984 if (val[1] < 0)
5985 val[0] = -1;
5986 }
5987 else if (val[0] & (((HOST_WIDE_INT) 1)
5988 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
5989 val[0] |= ((HOST_WIDE_INT) -1)
5990 << (bitpos - HOST_BITS_PER_WIDE_INT);
5991 }
5992
5993 value = build_int_cst_wide (type, val[1], val[0]);
5994 add_pending_init (purpose, value);
5995 }
5996
5997 constructor_incremental = 0;
5998 }
5999
6000 /* Return value of FIELD in pending initializer or zero if the field was
6001 not initialized yet. */
6002
6003 static tree
6004 find_init_member (tree field)
6005 {
6006 struct init_node *p;
6007
6008 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6009 {
6010 if (constructor_incremental
6011 && tree_int_cst_lt (field, constructor_unfilled_index))
6012 set_nonincremental_init ();
6013
6014 p = constructor_pending_elts;
6015 while (p)
6016 {
6017 if (tree_int_cst_lt (field, p->purpose))
6018 p = p->left;
6019 else if (tree_int_cst_lt (p->purpose, field))
6020 p = p->right;
6021 else
6022 return p->value;
6023 }
6024 }
6025 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6026 {
6027 tree bitpos = bit_position (field);
6028
6029 if (constructor_incremental
6030 && (!constructor_unfilled_fields
6031 || tree_int_cst_lt (bitpos,
6032 bit_position (constructor_unfilled_fields))))
6033 set_nonincremental_init ();
6034
6035 p = constructor_pending_elts;
6036 while (p)
6037 {
6038 if (field == p->purpose)
6039 return p->value;
6040 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
6041 p = p->left;
6042 else
6043 p = p->right;
6044 }
6045 }
6046 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6047 {
6048 if (!VEC_empty (constructor_elt, constructor_elements)
6049 && (VEC_last (constructor_elt, constructor_elements)->index
6050 == field))
6051 return VEC_last (constructor_elt, constructor_elements)->value;
6052 }
6053 return 0;
6054 }
6055
6056 /* "Output" the next constructor element.
6057 At top level, really output it to assembler code now.
6058 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6059 TYPE is the data type that the containing data type wants here.
6060 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6061 If VALUE is a string constant, STRICT_STRING is true if it is
6062 unparenthesized or we should not warn here for it being parenthesized.
6063 For other types of VALUE, STRICT_STRING is not used.
6064
6065 PENDING if non-nil means output pending elements that belong
6066 right after this element. (PENDING is normally 1;
6067 it is 0 while outputting pending elements, to avoid recursion.) */
6068
6069 static void
6070 output_init_element (tree value, bool strict_string, tree type, tree field,
6071 int pending)
6072 {
6073 constructor_elt *celt;
6074
6075 if (type == error_mark_node || value == error_mark_node)
6076 {
6077 constructor_erroneous = 1;
6078 return;
6079 }
6080 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
6081 && (TREE_CODE (value) == STRING_CST
6082 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR)
6083 && !(TREE_CODE (value) == STRING_CST
6084 && TREE_CODE (type) == ARRAY_TYPE
6085 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
6086 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
6087 TYPE_MAIN_VARIANT (type)))
6088 value = array_to_pointer_conversion (value);
6089
6090 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
6091 && require_constant_value && !flag_isoc99 && pending)
6092 {
6093 /* As an extension, allow initializing objects with static storage
6094 duration with compound literals (which are then treated just as
6095 the brace enclosed list they contain). */
6096 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
6097 value = DECL_INITIAL (decl);
6098 }
6099
6100 if (value == error_mark_node)
6101 constructor_erroneous = 1;
6102 else if (!TREE_CONSTANT (value))
6103 constructor_constant = 0;
6104 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
6105 || ((TREE_CODE (constructor_type) == RECORD_TYPE
6106 || TREE_CODE (constructor_type) == UNION_TYPE)
6107 && DECL_C_BIT_FIELD (field)
6108 && TREE_CODE (value) != INTEGER_CST))
6109 constructor_simple = 0;
6110
6111 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
6112 {
6113 if (require_constant_value)
6114 {
6115 error_init ("initializer element is not constant");
6116 value = error_mark_node;
6117 }
6118 else if (require_constant_elements)
6119 pedwarn ("initializer element is not computable at load time");
6120 }
6121
6122 /* If this field is empty (and not at the end of structure),
6123 don't do anything other than checking the initializer. */
6124 if (field
6125 && (TREE_TYPE (field) == error_mark_node
6126 || (COMPLETE_TYPE_P (TREE_TYPE (field))
6127 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
6128 && (TREE_CODE (constructor_type) == ARRAY_TYPE
6129 || TREE_CHAIN (field)))))
6130 return;
6131
6132 value = digest_init (type, value, strict_string, require_constant_value);
6133 if (value == error_mark_node)
6134 {
6135 constructor_erroneous = 1;
6136 return;
6137 }
6138
6139 /* If this element doesn't come next in sequence,
6140 put it on constructor_pending_elts. */
6141 if (TREE_CODE (constructor_type) == ARRAY_TYPE
6142 && (!constructor_incremental
6143 || !tree_int_cst_equal (field, constructor_unfilled_index)))
6144 {
6145 if (constructor_incremental
6146 && tree_int_cst_lt (field, constructor_unfilled_index))
6147 set_nonincremental_init ();
6148
6149 add_pending_init (field, value);
6150 return;
6151 }
6152 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6153 && (!constructor_incremental
6154 || field != constructor_unfilled_fields))
6155 {
6156 /* We do this for records but not for unions. In a union,
6157 no matter which field is specified, it can be initialized
6158 right away since it starts at the beginning of the union. */
6159 if (constructor_incremental)
6160 {
6161 if (!constructor_unfilled_fields)
6162 set_nonincremental_init ();
6163 else
6164 {
6165 tree bitpos, unfillpos;
6166
6167 bitpos = bit_position (field);
6168 unfillpos = bit_position (constructor_unfilled_fields);
6169
6170 if (tree_int_cst_lt (bitpos, unfillpos))
6171 set_nonincremental_init ();
6172 }
6173 }
6174
6175 add_pending_init (field, value);
6176 return;
6177 }
6178 else if (TREE_CODE (constructor_type) == UNION_TYPE
6179 && !VEC_empty (constructor_elt, constructor_elements))
6180 {
6181 if (TREE_SIDE_EFFECTS (VEC_last (constructor_elt,
6182 constructor_elements)->value))
6183 warning_init ("initialized field with side-effects overwritten");
6184 else if (warn_override_init)
6185 warning_init ("initialized field overwritten");
6186
6187 /* We can have just one union field set. */
6188 constructor_elements = 0;
6189 }
6190
6191 /* Otherwise, output this element either to
6192 constructor_elements or to the assembler file. */
6193
6194 celt = VEC_safe_push (constructor_elt, gc, constructor_elements, NULL);
6195 celt->index = field;
6196 celt->value = value;
6197
6198 /* Advance the variable that indicates sequential elements output. */
6199 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6200 constructor_unfilled_index
6201 = size_binop (PLUS_EXPR, constructor_unfilled_index,
6202 bitsize_one_node);
6203 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6204 {
6205 constructor_unfilled_fields
6206 = TREE_CHAIN (constructor_unfilled_fields);
6207
6208 /* Skip any nameless bit fields. */
6209 while (constructor_unfilled_fields != 0
6210 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6211 && DECL_NAME (constructor_unfilled_fields) == 0)
6212 constructor_unfilled_fields =
6213 TREE_CHAIN (constructor_unfilled_fields);
6214 }
6215 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6216 constructor_unfilled_fields = 0;
6217
6218 /* Now output any pending elements which have become next. */
6219 if (pending)
6220 output_pending_init_elements (0);
6221 }
6222
6223 /* Output any pending elements which have become next.
6224 As we output elements, constructor_unfilled_{fields,index}
6225 advances, which may cause other elements to become next;
6226 if so, they too are output.
6227
6228 If ALL is 0, we return when there are
6229 no more pending elements to output now.
6230
6231 If ALL is 1, we output space as necessary so that
6232 we can output all the pending elements. */
6233
6234 static void
6235 output_pending_init_elements (int all)
6236 {
6237 struct init_node *elt = constructor_pending_elts;
6238 tree next;
6239
6240 retry:
6241
6242 /* Look through the whole pending tree.
6243 If we find an element that should be output now,
6244 output it. Otherwise, set NEXT to the element
6245 that comes first among those still pending. */
6246
6247 next = 0;
6248 while (elt)
6249 {
6250 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6251 {
6252 if (tree_int_cst_equal (elt->purpose,
6253 constructor_unfilled_index))
6254 output_init_element (elt->value, true,
6255 TREE_TYPE (constructor_type),
6256 constructor_unfilled_index, 0);
6257 else if (tree_int_cst_lt (constructor_unfilled_index,
6258 elt->purpose))
6259 {
6260 /* Advance to the next smaller node. */
6261 if (elt->left)
6262 elt = elt->left;
6263 else
6264 {
6265 /* We have reached the smallest node bigger than the
6266 current unfilled index. Fill the space first. */
6267 next = elt->purpose;
6268 break;
6269 }
6270 }
6271 else
6272 {
6273 /* Advance to the next bigger node. */
6274 if (elt->right)
6275 elt = elt->right;
6276 else
6277 {
6278 /* We have reached the biggest node in a subtree. Find
6279 the parent of it, which is the next bigger node. */
6280 while (elt->parent && elt->parent->right == elt)
6281 elt = elt->parent;
6282 elt = elt->parent;
6283 if (elt && tree_int_cst_lt (constructor_unfilled_index,
6284 elt->purpose))
6285 {
6286 next = elt->purpose;
6287 break;
6288 }
6289 }
6290 }
6291 }
6292 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6293 || TREE_CODE (constructor_type) == UNION_TYPE)
6294 {
6295 tree ctor_unfilled_bitpos, elt_bitpos;
6296
6297 /* If the current record is complete we are done. */
6298 if (constructor_unfilled_fields == 0)
6299 break;
6300
6301 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
6302 elt_bitpos = bit_position (elt->purpose);
6303 /* We can't compare fields here because there might be empty
6304 fields in between. */
6305 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
6306 {
6307 constructor_unfilled_fields = elt->purpose;
6308 output_init_element (elt->value, true, TREE_TYPE (elt->purpose),
6309 elt->purpose, 0);
6310 }
6311 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
6312 {
6313 /* Advance to the next smaller node. */
6314 if (elt->left)
6315 elt = elt->left;
6316 else
6317 {
6318 /* We have reached the smallest node bigger than the
6319 current unfilled field. Fill the space first. */
6320 next = elt->purpose;
6321 break;
6322 }
6323 }
6324 else
6325 {
6326 /* Advance to the next bigger node. */
6327 if (elt->right)
6328 elt = elt->right;
6329 else
6330 {
6331 /* We have reached the biggest node in a subtree. Find
6332 the parent of it, which is the next bigger node. */
6333 while (elt->parent && elt->parent->right == elt)
6334 elt = elt->parent;
6335 elt = elt->parent;
6336 if (elt
6337 && (tree_int_cst_lt (ctor_unfilled_bitpos,
6338 bit_position (elt->purpose))))
6339 {
6340 next = elt->purpose;
6341 break;
6342 }
6343 }
6344 }
6345 }
6346 }
6347
6348 /* Ordinarily return, but not if we want to output all
6349 and there are elements left. */
6350 if (!(all && next != 0))
6351 return;
6352
6353 /* If it's not incremental, just skip over the gap, so that after
6354 jumping to retry we will output the next successive element. */
6355 if (TREE_CODE (constructor_type) == RECORD_TYPE
6356 || TREE_CODE (constructor_type) == UNION_TYPE)
6357 constructor_unfilled_fields = next;
6358 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6359 constructor_unfilled_index = next;
6360
6361 /* ELT now points to the node in the pending tree with the next
6362 initializer to output. */
6363 goto retry;
6364 }
6365 \f
6366 /* Add one non-braced element to the current constructor level.
6367 This adjusts the current position within the constructor's type.
6368 This may also start or terminate implicit levels
6369 to handle a partly-braced initializer.
6370
6371 Once this has found the correct level for the new element,
6372 it calls output_init_element. */
6373
6374 void
6375 process_init_element (struct c_expr value)
6376 {
6377 tree orig_value = value.value;
6378 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
6379 bool strict_string = value.original_code == STRING_CST;
6380
6381 designator_depth = 0;
6382 designator_erroneous = 0;
6383
6384 /* Handle superfluous braces around string cst as in
6385 char x[] = {"foo"}; */
6386 if (string_flag
6387 && constructor_type
6388 && TREE_CODE (constructor_type) == ARRAY_TYPE
6389 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
6390 && integer_zerop (constructor_unfilled_index))
6391 {
6392 if (constructor_stack->replacement_value.value)
6393 error_init ("excess elements in char array initializer");
6394 constructor_stack->replacement_value = value;
6395 return;
6396 }
6397
6398 if (constructor_stack->replacement_value.value != 0)
6399 {
6400 error_init ("excess elements in struct initializer");
6401 return;
6402 }
6403
6404 /* Ignore elements of a brace group if it is entirely superfluous
6405 and has already been diagnosed. */
6406 if (constructor_type == 0)
6407 return;
6408
6409 /* If we've exhausted any levels that didn't have braces,
6410 pop them now. */
6411 while (constructor_stack->implicit)
6412 {
6413 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6414 || TREE_CODE (constructor_type) == UNION_TYPE)
6415 && constructor_fields == 0)
6416 process_init_element (pop_init_level (1));
6417 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6418 && (constructor_max_index == 0
6419 || tree_int_cst_lt (constructor_max_index,
6420 constructor_index)))
6421 process_init_element (pop_init_level (1));
6422 else
6423 break;
6424 }
6425
6426 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6427 if (constructor_range_stack)
6428 {
6429 /* If value is a compound literal and we'll be just using its
6430 content, don't put it into a SAVE_EXPR. */
6431 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
6432 || !require_constant_value
6433 || flag_isoc99)
6434 value.value = save_expr (value.value);
6435 }
6436
6437 while (1)
6438 {
6439 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6440 {
6441 tree fieldtype;
6442 enum tree_code fieldcode;
6443
6444 if (constructor_fields == 0)
6445 {
6446 pedwarn_init ("excess elements in struct initializer");
6447 break;
6448 }
6449
6450 fieldtype = TREE_TYPE (constructor_fields);
6451 if (fieldtype != error_mark_node)
6452 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6453 fieldcode = TREE_CODE (fieldtype);
6454
6455 /* Error for non-static initialization of a flexible array member. */
6456 if (fieldcode == ARRAY_TYPE
6457 && !require_constant_value
6458 && TYPE_SIZE (fieldtype) == NULL_TREE
6459 && TREE_CHAIN (constructor_fields) == NULL_TREE)
6460 {
6461 error_init ("non-static initialization of a flexible array member");
6462 break;
6463 }
6464
6465 /* Accept a string constant to initialize a subarray. */
6466 if (value.value != 0
6467 && fieldcode == ARRAY_TYPE
6468 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6469 && string_flag)
6470 value.value = orig_value;
6471 /* Otherwise, if we have come to a subaggregate,
6472 and we don't have an element of its type, push into it. */
6473 else if (value.value != 0
6474 && value.value != error_mark_node
6475 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6476 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6477 || fieldcode == UNION_TYPE))
6478 {
6479 push_init_level (1);
6480 continue;
6481 }
6482
6483 if (value.value)
6484 {
6485 push_member_name (constructor_fields);
6486 output_init_element (value.value, strict_string,
6487 fieldtype, constructor_fields, 1);
6488 RESTORE_SPELLING_DEPTH (constructor_depth);
6489 }
6490 else
6491 /* Do the bookkeeping for an element that was
6492 directly output as a constructor. */
6493 {
6494 /* For a record, keep track of end position of last field. */
6495 if (DECL_SIZE (constructor_fields))
6496 constructor_bit_index
6497 = size_binop (PLUS_EXPR,
6498 bit_position (constructor_fields),
6499 DECL_SIZE (constructor_fields));
6500
6501 /* If the current field was the first one not yet written out,
6502 it isn't now, so update. */
6503 if (constructor_unfilled_fields == constructor_fields)
6504 {
6505 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6506 /* Skip any nameless bit fields. */
6507 while (constructor_unfilled_fields != 0
6508 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6509 && DECL_NAME (constructor_unfilled_fields) == 0)
6510 constructor_unfilled_fields =
6511 TREE_CHAIN (constructor_unfilled_fields);
6512 }
6513 }
6514
6515 constructor_fields = TREE_CHAIN (constructor_fields);
6516 /* Skip any nameless bit fields at the beginning. */
6517 while (constructor_fields != 0
6518 && DECL_C_BIT_FIELD (constructor_fields)
6519 && DECL_NAME (constructor_fields) == 0)
6520 constructor_fields = TREE_CHAIN (constructor_fields);
6521 }
6522 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6523 {
6524 tree fieldtype;
6525 enum tree_code fieldcode;
6526
6527 if (constructor_fields == 0)
6528 {
6529 pedwarn_init ("excess elements in union initializer");
6530 break;
6531 }
6532
6533 fieldtype = TREE_TYPE (constructor_fields);
6534 if (fieldtype != error_mark_node)
6535 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6536 fieldcode = TREE_CODE (fieldtype);
6537
6538 /* Warn that traditional C rejects initialization of unions.
6539 We skip the warning if the value is zero. This is done
6540 under the assumption that the zero initializer in user
6541 code appears conditioned on e.g. __STDC__ to avoid
6542 "missing initializer" warnings and relies on default
6543 initialization to zero in the traditional C case.
6544 We also skip the warning if the initializer is designated,
6545 again on the assumption that this must be conditional on
6546 __STDC__ anyway (and we've already complained about the
6547 member-designator already). */
6548 if (!in_system_header && !constructor_designated
6549 && !(value.value && (integer_zerop (value.value)
6550 || real_zerop (value.value))))
6551 warning (OPT_Wtraditional, "traditional C rejects initialization "
6552 "of unions");
6553
6554 /* Accept a string constant to initialize a subarray. */
6555 if (value.value != 0
6556 && fieldcode == ARRAY_TYPE
6557 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6558 && string_flag)
6559 value.value = orig_value;
6560 /* Otherwise, if we have come to a subaggregate,
6561 and we don't have an element of its type, push into it. */
6562 else if (value.value != 0
6563 && value.value != error_mark_node
6564 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6565 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6566 || fieldcode == UNION_TYPE))
6567 {
6568 push_init_level (1);
6569 continue;
6570 }
6571
6572 if (value.value)
6573 {
6574 push_member_name (constructor_fields);
6575 output_init_element (value.value, strict_string,
6576 fieldtype, constructor_fields, 1);
6577 RESTORE_SPELLING_DEPTH (constructor_depth);
6578 }
6579 else
6580 /* Do the bookkeeping for an element that was
6581 directly output as a constructor. */
6582 {
6583 constructor_bit_index = DECL_SIZE (constructor_fields);
6584 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6585 }
6586
6587 constructor_fields = 0;
6588 }
6589 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6590 {
6591 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6592 enum tree_code eltcode = TREE_CODE (elttype);
6593
6594 /* Accept a string constant to initialize a subarray. */
6595 if (value.value != 0
6596 && eltcode == ARRAY_TYPE
6597 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
6598 && string_flag)
6599 value.value = orig_value;
6600 /* Otherwise, if we have come to a subaggregate,
6601 and we don't have an element of its type, push into it. */
6602 else if (value.value != 0
6603 && value.value != error_mark_node
6604 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
6605 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6606 || eltcode == UNION_TYPE))
6607 {
6608 push_init_level (1);
6609 continue;
6610 }
6611
6612 if (constructor_max_index != 0
6613 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6614 || integer_all_onesp (constructor_max_index)))
6615 {
6616 pedwarn_init ("excess elements in array initializer");
6617 break;
6618 }
6619
6620 /* Now output the actual element. */
6621 if (value.value)
6622 {
6623 push_array_bounds (tree_low_cst (constructor_index, 1));
6624 output_init_element (value.value, strict_string,
6625 elttype, constructor_index, 1);
6626 RESTORE_SPELLING_DEPTH (constructor_depth);
6627 }
6628
6629 constructor_index
6630 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6631
6632 if (!value.value)
6633 /* If we are doing the bookkeeping for an element that was
6634 directly output as a constructor, we must update
6635 constructor_unfilled_index. */
6636 constructor_unfilled_index = constructor_index;
6637 }
6638 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6639 {
6640 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6641
6642 /* Do a basic check of initializer size. Note that vectors
6643 always have a fixed size derived from their type. */
6644 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6645 {
6646 pedwarn_init ("excess elements in vector initializer");
6647 break;
6648 }
6649
6650 /* Now output the actual element. */
6651 if (value.value)
6652 output_init_element (value.value, strict_string,
6653 elttype, constructor_index, 1);
6654
6655 constructor_index
6656 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6657
6658 if (!value.value)
6659 /* If we are doing the bookkeeping for an element that was
6660 directly output as a constructor, we must update
6661 constructor_unfilled_index. */
6662 constructor_unfilled_index = constructor_index;
6663 }
6664
6665 /* Handle the sole element allowed in a braced initializer
6666 for a scalar variable. */
6667 else if (constructor_type != error_mark_node
6668 && constructor_fields == 0)
6669 {
6670 pedwarn_init ("excess elements in scalar initializer");
6671 break;
6672 }
6673 else
6674 {
6675 if (value.value)
6676 output_init_element (value.value, strict_string,
6677 constructor_type, NULL_TREE, 1);
6678 constructor_fields = 0;
6679 }
6680
6681 /* Handle range initializers either at this level or anywhere higher
6682 in the designator stack. */
6683 if (constructor_range_stack)
6684 {
6685 struct constructor_range_stack *p, *range_stack;
6686 int finish = 0;
6687
6688 range_stack = constructor_range_stack;
6689 constructor_range_stack = 0;
6690 while (constructor_stack != range_stack->stack)
6691 {
6692 gcc_assert (constructor_stack->implicit);
6693 process_init_element (pop_init_level (1));
6694 }
6695 for (p = range_stack;
6696 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6697 p = p->prev)
6698 {
6699 gcc_assert (constructor_stack->implicit);
6700 process_init_element (pop_init_level (1));
6701 }
6702
6703 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6704 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6705 finish = 1;
6706
6707 while (1)
6708 {
6709 constructor_index = p->index;
6710 constructor_fields = p->fields;
6711 if (finish && p->range_end && p->index == p->range_start)
6712 {
6713 finish = 0;
6714 p->prev = 0;
6715 }
6716 p = p->next;
6717 if (!p)
6718 break;
6719 push_init_level (2);
6720 p->stack = constructor_stack;
6721 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6722 p->index = p->range_start;
6723 }
6724
6725 if (!finish)
6726 constructor_range_stack = range_stack;
6727 continue;
6728 }
6729
6730 break;
6731 }
6732
6733 constructor_range_stack = 0;
6734 }
6735 \f
6736 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
6737 (guaranteed to be 'volatile' or null) and ARGS (represented using
6738 an ASM_EXPR node). */
6739 tree
6740 build_asm_stmt (tree cv_qualifier, tree args)
6741 {
6742 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6743 ASM_VOLATILE_P (args) = 1;
6744 return add_stmt (args);
6745 }
6746
6747 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6748 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6749 SIMPLE indicates whether there was anything at all after the
6750 string in the asm expression -- asm("blah") and asm("blah" : )
6751 are subtly different. We use a ASM_EXPR node to represent this. */
6752 tree
6753 build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6754 bool simple)
6755 {
6756 tree tail;
6757 tree args;
6758 int i;
6759 const char *constraint;
6760 const char **oconstraints;
6761 bool allows_mem, allows_reg, is_inout;
6762 int ninputs, noutputs;
6763
6764 ninputs = list_length (inputs);
6765 noutputs = list_length (outputs);
6766 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
6767
6768 string = resolve_asm_operand_names (string, outputs, inputs);
6769
6770 /* Remove output conversions that change the type but not the mode. */
6771 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6772 {
6773 tree output = TREE_VALUE (tail);
6774
6775 /* ??? Really, this should not be here. Users should be using a
6776 proper lvalue, dammit. But there's a long history of using casts
6777 in the output operands. In cases like longlong.h, this becomes a
6778 primitive form of typechecking -- if the cast can be removed, then
6779 the output operand had a type of the proper width; otherwise we'll
6780 get an error. Gross, but ... */
6781 STRIP_NOPS (output);
6782
6783 if (!lvalue_or_else (output, lv_asm))
6784 output = error_mark_node;
6785
6786 if (output != error_mark_node
6787 && (TREE_READONLY (output)
6788 || TYPE_READONLY (TREE_TYPE (output))
6789 || ((TREE_CODE (TREE_TYPE (output)) == RECORD_TYPE
6790 || TREE_CODE (TREE_TYPE (output)) == UNION_TYPE)
6791 && C_TYPE_FIELDS_READONLY (TREE_TYPE (output)))))
6792 readonly_error (output, lv_asm);
6793
6794 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6795 oconstraints[i] = constraint;
6796
6797 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
6798 &allows_mem, &allows_reg, &is_inout))
6799 {
6800 /* If the operand is going to end up in memory,
6801 mark it addressable. */
6802 if (!allows_reg && !c_mark_addressable (output))
6803 output = error_mark_node;
6804 }
6805 else
6806 output = error_mark_node;
6807
6808 TREE_VALUE (tail) = output;
6809 }
6810
6811 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
6812 {
6813 tree input;
6814
6815 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6816 input = TREE_VALUE (tail);
6817
6818 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
6819 oconstraints, &allows_mem, &allows_reg))
6820 {
6821 /* If the operand is going to end up in memory,
6822 mark it addressable. */
6823 if (!allows_reg && allows_mem)
6824 {
6825 /* Strip the nops as we allow this case. FIXME, this really
6826 should be rejected or made deprecated. */
6827 STRIP_NOPS (input);
6828 if (!c_mark_addressable (input))
6829 input = error_mark_node;
6830 }
6831 }
6832 else
6833 input = error_mark_node;
6834
6835 TREE_VALUE (tail) = input;
6836 }
6837
6838 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers);
6839
6840 /* asm statements without outputs, including simple ones, are treated
6841 as volatile. */
6842 ASM_INPUT_P (args) = simple;
6843 ASM_VOLATILE_P (args) = (noutputs == 0);
6844
6845 return args;
6846 }
6847 \f
6848 /* Generate a goto statement to LABEL. */
6849
6850 tree
6851 c_finish_goto_label (tree label)
6852 {
6853 tree decl = lookup_label (label);
6854 if (!decl)
6855 return NULL_TREE;
6856
6857 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl))
6858 {
6859 error ("jump into statement expression");
6860 return NULL_TREE;
6861 }
6862
6863 if (C_DECL_UNJUMPABLE_VM (decl))
6864 {
6865 error ("jump into scope of identifier with variably modified type");
6866 return NULL_TREE;
6867 }
6868
6869 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl))
6870 {
6871 /* No jump from outside this statement expression context, so
6872 record that there is a jump from within this context. */
6873 struct c_label_list *nlist;
6874 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6875 nlist->next = label_context_stack_se->labels_used;
6876 nlist->label = decl;
6877 label_context_stack_se->labels_used = nlist;
6878 }
6879
6880 if (!C_DECL_UNDEFINABLE_VM (decl))
6881 {
6882 /* No jump from outside this context context of identifiers with
6883 variably modified type, so record that there is a jump from
6884 within this context. */
6885 struct c_label_list *nlist;
6886 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6887 nlist->next = label_context_stack_vm->labels_used;
6888 nlist->label = decl;
6889 label_context_stack_vm->labels_used = nlist;
6890 }
6891
6892 TREE_USED (decl) = 1;
6893 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl));
6894 }
6895
6896 /* Generate a computed goto statement to EXPR. */
6897
6898 tree
6899 c_finish_goto_ptr (tree expr)
6900 {
6901 if (pedantic)
6902 pedwarn ("ISO C forbids %<goto *expr;%>");
6903 expr = convert (ptr_type_node, expr);
6904 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr));
6905 }
6906
6907 /* Generate a C `return' statement. RETVAL is the expression for what
6908 to return, or a null pointer for `return;' with no value. */
6909
6910 tree
6911 c_finish_return (tree retval)
6912 {
6913 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)), ret_stmt;
6914 bool no_warning = false;
6915
6916 if (TREE_THIS_VOLATILE (current_function_decl))
6917 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6918
6919 if (!retval)
6920 {
6921 current_function_returns_null = 1;
6922 if ((warn_return_type || flag_isoc99)
6923 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6924 {
6925 pedwarn_c99 ("%<return%> with no value, in "
6926 "function returning non-void");
6927 no_warning = true;
6928 }
6929 }
6930 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6931 {
6932 current_function_returns_null = 1;
6933 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6934 pedwarn ("%<return%> with a value, in function returning void");
6935 }
6936 else
6937 {
6938 tree t = convert_for_assignment (valtype, retval, ic_return,
6939 NULL_TREE, NULL_TREE, 0);
6940 tree res = DECL_RESULT (current_function_decl);
6941 tree inner;
6942
6943 current_function_returns_value = 1;
6944 if (t == error_mark_node)
6945 return NULL_TREE;
6946
6947 inner = t = convert (TREE_TYPE (res), t);
6948
6949 /* Strip any conversions, additions, and subtractions, and see if
6950 we are returning the address of a local variable. Warn if so. */
6951 while (1)
6952 {
6953 switch (TREE_CODE (inner))
6954 {
6955 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6956 case PLUS_EXPR:
6957 inner = TREE_OPERAND (inner, 0);
6958 continue;
6959
6960 case MINUS_EXPR:
6961 /* If the second operand of the MINUS_EXPR has a pointer
6962 type (or is converted from it), this may be valid, so
6963 don't give a warning. */
6964 {
6965 tree op1 = TREE_OPERAND (inner, 1);
6966
6967 while (!POINTER_TYPE_P (TREE_TYPE (op1))
6968 && (TREE_CODE (op1) == NOP_EXPR
6969 || TREE_CODE (op1) == NON_LVALUE_EXPR
6970 || TREE_CODE (op1) == CONVERT_EXPR))
6971 op1 = TREE_OPERAND (op1, 0);
6972
6973 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6974 break;
6975
6976 inner = TREE_OPERAND (inner, 0);
6977 continue;
6978 }
6979
6980 case ADDR_EXPR:
6981 inner = TREE_OPERAND (inner, 0);
6982
6983 while (REFERENCE_CLASS_P (inner)
6984 && TREE_CODE (inner) != INDIRECT_REF)
6985 inner = TREE_OPERAND (inner, 0);
6986
6987 if (DECL_P (inner)
6988 && !DECL_EXTERNAL (inner)
6989 && !TREE_STATIC (inner)
6990 && DECL_CONTEXT (inner) == current_function_decl)
6991 warning (0, "function returns address of local variable");
6992 break;
6993
6994 default:
6995 break;
6996 }
6997
6998 break;
6999 }
7000
7001 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
7002 }
7003
7004 ret_stmt = build_stmt (RETURN_EXPR, retval);
7005 TREE_NO_WARNING (ret_stmt) |= no_warning;
7006 return add_stmt (ret_stmt);
7007 }
7008 \f
7009 struct c_switch {
7010 /* The SWITCH_EXPR being built. */
7011 tree switch_expr;
7012
7013 /* The original type of the testing expression, i.e. before the
7014 default conversion is applied. */
7015 tree orig_type;
7016
7017 /* A splay-tree mapping the low element of a case range to the high
7018 element, or NULL_TREE if there is no high element. Used to
7019 determine whether or not a new case label duplicates an old case
7020 label. We need a tree, rather than simply a hash table, because
7021 of the GNU case range extension. */
7022 splay_tree cases;
7023
7024 /* Number of nested statement expressions within this switch
7025 statement; if nonzero, case and default labels may not
7026 appear. */
7027 unsigned int blocked_stmt_expr;
7028
7029 /* Scope of outermost declarations of identifiers with variably
7030 modified type within this switch statement; if nonzero, case and
7031 default labels may not appear. */
7032 unsigned int blocked_vm;
7033
7034 /* The next node on the stack. */
7035 struct c_switch *next;
7036 };
7037
7038 /* A stack of the currently active switch statements. The innermost
7039 switch statement is on the top of the stack. There is no need to
7040 mark the stack for garbage collection because it is only active
7041 during the processing of the body of a function, and we never
7042 collect at that point. */
7043
7044 struct c_switch *c_switch_stack;
7045
7046 /* Start a C switch statement, testing expression EXP. Return the new
7047 SWITCH_EXPR. */
7048
7049 tree
7050 c_start_case (tree exp)
7051 {
7052 tree orig_type = error_mark_node;
7053 struct c_switch *cs;
7054
7055 if (exp != error_mark_node)
7056 {
7057 orig_type = TREE_TYPE (exp);
7058
7059 if (!INTEGRAL_TYPE_P (orig_type))
7060 {
7061 if (orig_type != error_mark_node)
7062 {
7063 error ("switch quantity not an integer");
7064 orig_type = error_mark_node;
7065 }
7066 exp = integer_zero_node;
7067 }
7068 else
7069 {
7070 tree type = TYPE_MAIN_VARIANT (orig_type);
7071
7072 if (!in_system_header
7073 && (type == long_integer_type_node
7074 || type == long_unsigned_type_node))
7075 warning (OPT_Wtraditional, "%<long%> switch expression not "
7076 "converted to %<int%> in ISO C");
7077
7078 exp = default_conversion (exp);
7079 }
7080 }
7081
7082 /* Add this new SWITCH_EXPR to the stack. */
7083 cs = XNEW (struct c_switch);
7084 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE);
7085 cs->orig_type = orig_type;
7086 cs->cases = splay_tree_new (case_compare, NULL, NULL);
7087 cs->blocked_stmt_expr = 0;
7088 cs->blocked_vm = 0;
7089 cs->next = c_switch_stack;
7090 c_switch_stack = cs;
7091
7092 return add_stmt (cs->switch_expr);
7093 }
7094
7095 /* Process a case label. */
7096
7097 tree
7098 do_case (tree low_value, tree high_value)
7099 {
7100 tree label = NULL_TREE;
7101
7102 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr
7103 && !c_switch_stack->blocked_vm)
7104 {
7105 label = c_add_case_label (c_switch_stack->cases,
7106 SWITCH_COND (c_switch_stack->switch_expr),
7107 c_switch_stack->orig_type,
7108 low_value, high_value);
7109 if (label == error_mark_node)
7110 label = NULL_TREE;
7111 }
7112 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr)
7113 {
7114 if (low_value)
7115 error ("case label in statement expression not containing "
7116 "enclosing switch statement");
7117 else
7118 error ("%<default%> label in statement expression not containing "
7119 "enclosing switch statement");
7120 }
7121 else if (c_switch_stack && c_switch_stack->blocked_vm)
7122 {
7123 if (low_value)
7124 error ("case label in scope of identifier with variably modified "
7125 "type not containing enclosing switch statement");
7126 else
7127 error ("%<default%> label in scope of identifier with variably "
7128 "modified type not containing enclosing switch statement");
7129 }
7130 else if (low_value)
7131 error ("case label not within a switch statement");
7132 else
7133 error ("%<default%> label not within a switch statement");
7134
7135 return label;
7136 }
7137
7138 /* Finish the switch statement. */
7139
7140 void
7141 c_finish_case (tree body)
7142 {
7143 struct c_switch *cs = c_switch_stack;
7144 location_t switch_location;
7145
7146 SWITCH_BODY (cs->switch_expr) = body;
7147
7148 /* We must not be within a statement expression nested in the switch
7149 at this point; we might, however, be within the scope of an
7150 identifier with variably modified type nested in the switch. */
7151 gcc_assert (!cs->blocked_stmt_expr);
7152
7153 /* Emit warnings as needed. */
7154 if (EXPR_HAS_LOCATION (cs->switch_expr))
7155 switch_location = EXPR_LOCATION (cs->switch_expr);
7156 else
7157 switch_location = input_location;
7158 c_do_switch_warnings (cs->cases, switch_location,
7159 TREE_TYPE (cs->switch_expr),
7160 SWITCH_COND (cs->switch_expr));
7161
7162 /* Pop the stack. */
7163 c_switch_stack = cs->next;
7164 splay_tree_delete (cs->cases);
7165 XDELETE (cs);
7166 }
7167 \f
7168 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
7169 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
7170 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
7171 statement, and was not surrounded with parenthesis. */
7172
7173 void
7174 c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
7175 tree else_block, bool nested_if)
7176 {
7177 tree stmt;
7178
7179 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
7180 if (warn_parentheses && nested_if && else_block == NULL)
7181 {
7182 tree inner_if = then_block;
7183
7184 /* We know from the grammar productions that there is an IF nested
7185 within THEN_BLOCK. Due to labels and c99 conditional declarations,
7186 it might not be exactly THEN_BLOCK, but should be the last
7187 non-container statement within. */
7188 while (1)
7189 switch (TREE_CODE (inner_if))
7190 {
7191 case COND_EXPR:
7192 goto found;
7193 case BIND_EXPR:
7194 inner_if = BIND_EXPR_BODY (inner_if);
7195 break;
7196 case STATEMENT_LIST:
7197 inner_if = expr_last (then_block);
7198 break;
7199 case TRY_FINALLY_EXPR:
7200 case TRY_CATCH_EXPR:
7201 inner_if = TREE_OPERAND (inner_if, 0);
7202 break;
7203 default:
7204 gcc_unreachable ();
7205 }
7206 found:
7207
7208 if (COND_EXPR_ELSE (inner_if))
7209 warning (OPT_Wparentheses,
7210 "%Hsuggest explicit braces to avoid ambiguous %<else%>",
7211 &if_locus);
7212 }
7213
7214 empty_body_warning (then_block, else_block);
7215
7216 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block);
7217 SET_EXPR_LOCATION (stmt, if_locus);
7218 add_stmt (stmt);
7219 }
7220
7221 /* Emit a general-purpose loop construct. START_LOCUS is the location of
7222 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
7223 is false for DO loops. INCR is the FOR increment expression. BODY is
7224 the statement controlled by the loop. BLAB is the break label. CLAB is
7225 the continue label. Everything is allowed to be NULL. */
7226
7227 void
7228 c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
7229 tree blab, tree clab, bool cond_is_first)
7230 {
7231 tree entry = NULL, exit = NULL, t;
7232
7233 /* If the condition is zero don't generate a loop construct. */
7234 if (cond && integer_zerop (cond))
7235 {
7236 if (cond_is_first)
7237 {
7238 t = build_and_jump (&blab);
7239 SET_EXPR_LOCATION (t, start_locus);
7240 add_stmt (t);
7241 }
7242 }
7243 else
7244 {
7245 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
7246
7247 /* If we have an exit condition, then we build an IF with gotos either
7248 out of the loop, or to the top of it. If there's no exit condition,
7249 then we just build a jump back to the top. */
7250 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
7251
7252 if (cond && !integer_nonzerop (cond))
7253 {
7254 /* Canonicalize the loop condition to the end. This means
7255 generating a branch to the loop condition. Reuse the
7256 continue label, if possible. */
7257 if (cond_is_first)
7258 {
7259 if (incr || !clab)
7260 {
7261 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
7262 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
7263 }
7264 else
7265 t = build1 (GOTO_EXPR, void_type_node, clab);
7266 SET_EXPR_LOCATION (t, start_locus);
7267 add_stmt (t);
7268 }
7269
7270 t = build_and_jump (&blab);
7271 exit = fold_build3 (COND_EXPR, void_type_node, cond, exit, t);
7272 if (cond_is_first)
7273 SET_EXPR_LOCATION (exit, start_locus);
7274 else
7275 SET_EXPR_LOCATION (exit, input_location);
7276 }
7277
7278 add_stmt (top);
7279 }
7280
7281 if (body)
7282 add_stmt (body);
7283 if (clab)
7284 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
7285 if (incr)
7286 add_stmt (incr);
7287 if (entry)
7288 add_stmt (entry);
7289 if (exit)
7290 add_stmt (exit);
7291 if (blab)
7292 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
7293 }
7294
7295 tree
7296 c_finish_bc_stmt (tree *label_p, bool is_break)
7297 {
7298 bool skip;
7299 tree label = *label_p;
7300
7301 /* In switch statements break is sometimes stylistically used after
7302 a return statement. This can lead to spurious warnings about
7303 control reaching the end of a non-void function when it is
7304 inlined. Note that we are calling block_may_fallthru with
7305 language specific tree nodes; this works because
7306 block_may_fallthru returns true when given something it does not
7307 understand. */
7308 skip = !block_may_fallthru (cur_stmt_list);
7309
7310 if (!label)
7311 {
7312 if (!skip)
7313 *label_p = label = create_artificial_label ();
7314 }
7315 else if (TREE_CODE (label) == LABEL_DECL)
7316 ;
7317 else switch (TREE_INT_CST_LOW (label))
7318 {
7319 case 0:
7320 if (is_break)
7321 error ("break statement not within loop or switch");
7322 else
7323 error ("continue statement not within a loop");
7324 return NULL_TREE;
7325
7326 case 1:
7327 gcc_assert (is_break);
7328 error ("break statement used with OpenMP for loop");
7329 return NULL_TREE;
7330
7331 default:
7332 gcc_unreachable ();
7333 }
7334
7335 if (skip)
7336 return NULL_TREE;
7337
7338 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
7339 }
7340
7341 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
7342
7343 static void
7344 emit_side_effect_warnings (tree expr)
7345 {
7346 if (expr == error_mark_node)
7347 ;
7348 else if (!TREE_SIDE_EFFECTS (expr))
7349 {
7350 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
7351 warning (0, "%Hstatement with no effect",
7352 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location);
7353 }
7354 else if (warn_unused_value)
7355 warn_if_unused_value (expr, input_location);
7356 }
7357
7358 /* Process an expression as if it were a complete statement. Emit
7359 diagnostics, but do not call ADD_STMT. */
7360
7361 tree
7362 c_process_expr_stmt (tree expr)
7363 {
7364 if (!expr)
7365 return NULL_TREE;
7366
7367 if (warn_sequence_point)
7368 verify_sequence_points (expr);
7369
7370 if (TREE_TYPE (expr) != error_mark_node
7371 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
7372 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
7373 error ("expression statement has incomplete type");
7374
7375 /* If we're not processing a statement expression, warn about unused values.
7376 Warnings for statement expressions will be emitted later, once we figure
7377 out which is the result. */
7378 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7379 && (extra_warnings || warn_unused_value))
7380 emit_side_effect_warnings (expr);
7381
7382 /* If the expression is not of a type to which we cannot assign a line
7383 number, wrap the thing in a no-op NOP_EXPR. */
7384 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
7385 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
7386
7387 if (CAN_HAVE_LOCATION_P (expr))
7388 SET_EXPR_LOCATION (expr, input_location);
7389
7390 return expr;
7391 }
7392
7393 /* Emit an expression as a statement. */
7394
7395 tree
7396 c_finish_expr_stmt (tree expr)
7397 {
7398 if (expr)
7399 return add_stmt (c_process_expr_stmt (expr));
7400 else
7401 return NULL;
7402 }
7403
7404 /* Do the opposite and emit a statement as an expression. To begin,
7405 create a new binding level and return it. */
7406
7407 tree
7408 c_begin_stmt_expr (void)
7409 {
7410 tree ret;
7411 struct c_label_context_se *nstack;
7412 struct c_label_list *glist;
7413
7414 /* We must force a BLOCK for this level so that, if it is not expanded
7415 later, there is a way to turn off the entire subtree of blocks that
7416 are contained in it. */
7417 keep_next_level ();
7418 ret = c_begin_compound_stmt (true);
7419 if (c_switch_stack)
7420 {
7421 c_switch_stack->blocked_stmt_expr++;
7422 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7423 }
7424 for (glist = label_context_stack_se->labels_used;
7425 glist != NULL;
7426 glist = glist->next)
7427 {
7428 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1;
7429 }
7430 nstack = XOBNEW (&parser_obstack, struct c_label_context_se);
7431 nstack->labels_def = NULL;
7432 nstack->labels_used = NULL;
7433 nstack->next = label_context_stack_se;
7434 label_context_stack_se = nstack;
7435
7436 /* Mark the current statement list as belonging to a statement list. */
7437 STATEMENT_LIST_STMT_EXPR (ret) = 1;
7438
7439 return ret;
7440 }
7441
7442 tree
7443 c_finish_stmt_expr (tree body)
7444 {
7445 tree last, type, tmp, val;
7446 tree *last_p;
7447 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7448
7449 body = c_end_compound_stmt (body, true);
7450 if (c_switch_stack)
7451 {
7452 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7453 c_switch_stack->blocked_stmt_expr--;
7454 }
7455 /* It is no longer possible to jump to labels defined within this
7456 statement expression. */
7457 for (dlist = label_context_stack_se->labels_def;
7458 dlist != NULL;
7459 dlist = dlist->next)
7460 {
7461 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1;
7462 }
7463 /* It is again possible to define labels with a goto just outside
7464 this statement expression. */
7465 for (glist = label_context_stack_se->next->labels_used;
7466 glist != NULL;
7467 glist = glist->next)
7468 {
7469 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0;
7470 glist_prev = glist;
7471 }
7472 if (glist_prev != NULL)
7473 glist_prev->next = label_context_stack_se->labels_used;
7474 else
7475 label_context_stack_se->next->labels_used
7476 = label_context_stack_se->labels_used;
7477 label_context_stack_se = label_context_stack_se->next;
7478
7479 /* Locate the last statement in BODY. See c_end_compound_stmt
7480 about always returning a BIND_EXPR. */
7481 last_p = &BIND_EXPR_BODY (body);
7482 last = BIND_EXPR_BODY (body);
7483
7484 continue_searching:
7485 if (TREE_CODE (last) == STATEMENT_LIST)
7486 {
7487 tree_stmt_iterator i;
7488
7489 /* This can happen with degenerate cases like ({ }). No value. */
7490 if (!TREE_SIDE_EFFECTS (last))
7491 return body;
7492
7493 /* If we're supposed to generate side effects warnings, process
7494 all of the statements except the last. */
7495 if (extra_warnings || warn_unused_value)
7496 {
7497 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
7498 emit_side_effect_warnings (tsi_stmt (i));
7499 }
7500 else
7501 i = tsi_last (last);
7502 last_p = tsi_stmt_ptr (i);
7503 last = *last_p;
7504 }
7505
7506 /* If the end of the list is exception related, then the list was split
7507 by a call to push_cleanup. Continue searching. */
7508 if (TREE_CODE (last) == TRY_FINALLY_EXPR
7509 || TREE_CODE (last) == TRY_CATCH_EXPR)
7510 {
7511 last_p = &TREE_OPERAND (last, 0);
7512 last = *last_p;
7513 goto continue_searching;
7514 }
7515
7516 /* In the case that the BIND_EXPR is not necessary, return the
7517 expression out from inside it. */
7518 if (last == error_mark_node
7519 || (last == BIND_EXPR_BODY (body)
7520 && BIND_EXPR_VARS (body) == NULL))
7521 {
7522 /* Do not warn if the return value of a statement expression is
7523 unused. */
7524 if (CAN_HAVE_LOCATION_P (last))
7525 TREE_NO_WARNING (last) = 1;
7526 return last;
7527 }
7528
7529 /* Extract the type of said expression. */
7530 type = TREE_TYPE (last);
7531
7532 /* If we're not returning a value at all, then the BIND_EXPR that
7533 we already have is a fine expression to return. */
7534 if (!type || VOID_TYPE_P (type))
7535 return body;
7536
7537 /* Now that we've located the expression containing the value, it seems
7538 silly to make voidify_wrapper_expr repeat the process. Create a
7539 temporary of the appropriate type and stick it in a TARGET_EXPR. */
7540 tmp = create_tmp_var_raw (type, NULL);
7541
7542 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
7543 tree_expr_nonnegative_p giving up immediately. */
7544 val = last;
7545 if (TREE_CODE (val) == NOP_EXPR
7546 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
7547 val = TREE_OPERAND (val, 0);
7548
7549 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
7550 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last));
7551
7552 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
7553 }
7554
7555 /* Begin the scope of an identifier of variably modified type, scope
7556 number SCOPE. Jumping from outside this scope to inside it is not
7557 permitted. */
7558
7559 void
7560 c_begin_vm_scope (unsigned int scope)
7561 {
7562 struct c_label_context_vm *nstack;
7563 struct c_label_list *glist;
7564
7565 gcc_assert (scope > 0);
7566
7567 /* At file_scope, we don't have to do any processing. */
7568 if (label_context_stack_vm == NULL)
7569 return;
7570
7571 if (c_switch_stack && !c_switch_stack->blocked_vm)
7572 c_switch_stack->blocked_vm = scope;
7573 for (glist = label_context_stack_vm->labels_used;
7574 glist != NULL;
7575 glist = glist->next)
7576 {
7577 C_DECL_UNDEFINABLE_VM (glist->label) = 1;
7578 }
7579 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm);
7580 nstack->labels_def = NULL;
7581 nstack->labels_used = NULL;
7582 nstack->scope = scope;
7583 nstack->next = label_context_stack_vm;
7584 label_context_stack_vm = nstack;
7585 }
7586
7587 /* End a scope which may contain identifiers of variably modified
7588 type, scope number SCOPE. */
7589
7590 void
7591 c_end_vm_scope (unsigned int scope)
7592 {
7593 if (label_context_stack_vm == NULL)
7594 return;
7595 if (c_switch_stack && c_switch_stack->blocked_vm == scope)
7596 c_switch_stack->blocked_vm = 0;
7597 /* We may have a number of nested scopes of identifiers with
7598 variably modified type, all at this depth. Pop each in turn. */
7599 while (label_context_stack_vm->scope == scope)
7600 {
7601 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7602
7603 /* It is no longer possible to jump to labels defined within this
7604 scope. */
7605 for (dlist = label_context_stack_vm->labels_def;
7606 dlist != NULL;
7607 dlist = dlist->next)
7608 {
7609 C_DECL_UNJUMPABLE_VM (dlist->label) = 1;
7610 }
7611 /* It is again possible to define labels with a goto just outside
7612 this scope. */
7613 for (glist = label_context_stack_vm->next->labels_used;
7614 glist != NULL;
7615 glist = glist->next)
7616 {
7617 C_DECL_UNDEFINABLE_VM (glist->label) = 0;
7618 glist_prev = glist;
7619 }
7620 if (glist_prev != NULL)
7621 glist_prev->next = label_context_stack_vm->labels_used;
7622 else
7623 label_context_stack_vm->next->labels_used
7624 = label_context_stack_vm->labels_used;
7625 label_context_stack_vm = label_context_stack_vm->next;
7626 }
7627 }
7628 \f
7629 /* Begin and end compound statements. This is as simple as pushing
7630 and popping new statement lists from the tree. */
7631
7632 tree
7633 c_begin_compound_stmt (bool do_scope)
7634 {
7635 tree stmt = push_stmt_list ();
7636 if (do_scope)
7637 push_scope ();
7638 return stmt;
7639 }
7640
7641 tree
7642 c_end_compound_stmt (tree stmt, bool do_scope)
7643 {
7644 tree block = NULL;
7645
7646 if (do_scope)
7647 {
7648 if (c_dialect_objc ())
7649 objc_clear_super_receiver ();
7650 block = pop_scope ();
7651 }
7652
7653 stmt = pop_stmt_list (stmt);
7654 stmt = c_build_bind_expr (block, stmt);
7655
7656 /* If this compound statement is nested immediately inside a statement
7657 expression, then force a BIND_EXPR to be created. Otherwise we'll
7658 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
7659 STATEMENT_LISTs merge, and thus we can lose track of what statement
7660 was really last. */
7661 if (cur_stmt_list
7662 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7663 && TREE_CODE (stmt) != BIND_EXPR)
7664 {
7665 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
7666 TREE_SIDE_EFFECTS (stmt) = 1;
7667 }
7668
7669 return stmt;
7670 }
7671
7672 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
7673 when the current scope is exited. EH_ONLY is true when this is not
7674 meant to apply to normal control flow transfer. */
7675
7676 void
7677 push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only)
7678 {
7679 enum tree_code code;
7680 tree stmt, list;
7681 bool stmt_expr;
7682
7683 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
7684 stmt = build_stmt (code, NULL, cleanup);
7685 add_stmt (stmt);
7686 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
7687 list = push_stmt_list ();
7688 TREE_OPERAND (stmt, 0) = list;
7689 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
7690 }
7691 \f
7692 /* Build a binary-operation expression without default conversions.
7693 CODE is the kind of expression to build.
7694 This function differs from `build' in several ways:
7695 the data type of the result is computed and recorded in it,
7696 warnings are generated if arg data types are invalid,
7697 special handling for addition and subtraction of pointers is known,
7698 and some optimization is done (operations on narrow ints
7699 are done in the narrower type when that gives the same result).
7700 Constant folding is also done before the result is returned.
7701
7702 Note that the operands will never have enumeral types, or function
7703 or array types, because either they will have the default conversions
7704 performed or they have both just been converted to some other type in which
7705 the arithmetic is to be done. */
7706
7707 tree
7708 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
7709 int convert_p)
7710 {
7711 tree type0, type1;
7712 enum tree_code code0, code1;
7713 tree op0, op1;
7714 const char *invalid_op_diag;
7715
7716 /* Expression code to give to the expression when it is built.
7717 Normally this is CODE, which is what the caller asked for,
7718 but in some special cases we change it. */
7719 enum tree_code resultcode = code;
7720
7721 /* Data type in which the computation is to be performed.
7722 In the simplest cases this is the common type of the arguments. */
7723 tree result_type = NULL;
7724
7725 /* Nonzero means operands have already been type-converted
7726 in whatever way is necessary.
7727 Zero means they need to be converted to RESULT_TYPE. */
7728 int converted = 0;
7729
7730 /* Nonzero means create the expression with this type, rather than
7731 RESULT_TYPE. */
7732 tree build_type = 0;
7733
7734 /* Nonzero means after finally constructing the expression
7735 convert it to this type. */
7736 tree final_type = 0;
7737
7738 /* Nonzero if this is an operation like MIN or MAX which can
7739 safely be computed in short if both args are promoted shorts.
7740 Also implies COMMON.
7741 -1 indicates a bitwise operation; this makes a difference
7742 in the exact conditions for when it is safe to do the operation
7743 in a narrower mode. */
7744 int shorten = 0;
7745
7746 /* Nonzero if this is a comparison operation;
7747 if both args are promoted shorts, compare the original shorts.
7748 Also implies COMMON. */
7749 int short_compare = 0;
7750
7751 /* Nonzero if this is a right-shift operation, which can be computed on the
7752 original short and then promoted if the operand is a promoted short. */
7753 int short_shift = 0;
7754
7755 /* Nonzero means set RESULT_TYPE to the common type of the args. */
7756 int common = 0;
7757
7758 /* True means types are compatible as far as ObjC is concerned. */
7759 bool objc_ok;
7760
7761 if (convert_p)
7762 {
7763 op0 = default_conversion (orig_op0);
7764 op1 = default_conversion (orig_op1);
7765 }
7766 else
7767 {
7768 op0 = orig_op0;
7769 op1 = orig_op1;
7770 }
7771
7772 type0 = TREE_TYPE (op0);
7773 type1 = TREE_TYPE (op1);
7774
7775 /* The expression codes of the data types of the arguments tell us
7776 whether the arguments are integers, floating, pointers, etc. */
7777 code0 = TREE_CODE (type0);
7778 code1 = TREE_CODE (type1);
7779
7780 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
7781 STRIP_TYPE_NOPS (op0);
7782 STRIP_TYPE_NOPS (op1);
7783
7784 /* If an error was already reported for one of the arguments,
7785 avoid reporting another error. */
7786
7787 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7788 return error_mark_node;
7789
7790 if ((invalid_op_diag
7791 = targetm.invalid_binary_op (code, type0, type1)))
7792 {
7793 error (invalid_op_diag);
7794 return error_mark_node;
7795 }
7796
7797 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE);
7798
7799 switch (code)
7800 {
7801 case PLUS_EXPR:
7802 /* Handle the pointer + int case. */
7803 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7804 return pointer_int_sum (PLUS_EXPR, op0, op1);
7805 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
7806 return pointer_int_sum (PLUS_EXPR, op1, op0);
7807 else
7808 common = 1;
7809 break;
7810
7811 case MINUS_EXPR:
7812 /* Subtraction of two similar pointers.
7813 We must subtract them as integers, then divide by object size. */
7814 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
7815 && comp_target_types (type0, type1))
7816 return pointer_diff (op0, op1);
7817 /* Handle pointer minus int. Just like pointer plus int. */
7818 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7819 return pointer_int_sum (MINUS_EXPR, op0, op1);
7820 else
7821 common = 1;
7822 break;
7823
7824 case MULT_EXPR:
7825 common = 1;
7826 break;
7827
7828 case TRUNC_DIV_EXPR:
7829 case CEIL_DIV_EXPR:
7830 case FLOOR_DIV_EXPR:
7831 case ROUND_DIV_EXPR:
7832 case EXACT_DIV_EXPR:
7833 /* Floating point division by zero is a legitimate way to obtain
7834 infinities and NaNs. */
7835 if (skip_evaluation == 0 && integer_zerop (op1))
7836 warning (OPT_Wdiv_by_zero, "division by zero");
7837
7838 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7839 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7840 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7841 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
7842 {
7843 enum tree_code tcode0 = code0, tcode1 = code1;
7844
7845 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7846 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
7847 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
7848 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
7849
7850 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
7851 resultcode = RDIV_EXPR;
7852 else
7853 /* Although it would be tempting to shorten always here, that
7854 loses on some targets, since the modulo instruction is
7855 undefined if the quotient can't be represented in the
7856 computation mode. We shorten only if unsigned or if
7857 dividing by something we know != -1. */
7858 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7859 || (TREE_CODE (op1) == INTEGER_CST
7860 && !integer_all_onesp (op1)));
7861 common = 1;
7862 }
7863 break;
7864
7865 case BIT_AND_EXPR:
7866 case BIT_IOR_EXPR:
7867 case BIT_XOR_EXPR:
7868 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7869 shorten = -1;
7870 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
7871 common = 1;
7872 break;
7873
7874 case TRUNC_MOD_EXPR:
7875 case FLOOR_MOD_EXPR:
7876 if (skip_evaluation == 0 && integer_zerop (op1))
7877 warning (OPT_Wdiv_by_zero, "division by zero");
7878
7879 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7880 {
7881 /* Although it would be tempting to shorten always here, that loses
7882 on some targets, since the modulo instruction is undefined if the
7883 quotient can't be represented in the computation mode. We shorten
7884 only if unsigned or if dividing by something we know != -1. */
7885 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7886 || (TREE_CODE (op1) == INTEGER_CST
7887 && !integer_all_onesp (op1)));
7888 common = 1;
7889 }
7890 break;
7891
7892 case TRUTH_ANDIF_EXPR:
7893 case TRUTH_ORIF_EXPR:
7894 case TRUTH_AND_EXPR:
7895 case TRUTH_OR_EXPR:
7896 case TRUTH_XOR_EXPR:
7897 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
7898 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
7899 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
7900 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
7901 {
7902 /* Result of these operations is always an int,
7903 but that does not mean the operands should be
7904 converted to ints! */
7905 result_type = integer_type_node;
7906 op0 = c_common_truthvalue_conversion (op0);
7907 op1 = c_common_truthvalue_conversion (op1);
7908 converted = 1;
7909 }
7910 break;
7911
7912 /* Shift operations: result has same type as first operand;
7913 always convert second operand to int.
7914 Also set SHORT_SHIFT if shifting rightward. */
7915
7916 case RSHIFT_EXPR:
7917 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7918 {
7919 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7920 {
7921 if (tree_int_cst_sgn (op1) < 0)
7922 warning (0, "right shift count is negative");
7923 else
7924 {
7925 if (!integer_zerop (op1))
7926 short_shift = 1;
7927
7928 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7929 warning (0, "right shift count >= width of type");
7930 }
7931 }
7932
7933 /* Use the type of the value to be shifted. */
7934 result_type = type0;
7935 /* Convert the shift-count to an integer, regardless of size
7936 of value being shifted. */
7937 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7938 op1 = convert (integer_type_node, op1);
7939 /* Avoid converting op1 to result_type later. */
7940 converted = 1;
7941 }
7942 break;
7943
7944 case LSHIFT_EXPR:
7945 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7946 {
7947 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7948 {
7949 if (tree_int_cst_sgn (op1) < 0)
7950 warning (0, "left shift count is negative");
7951
7952 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7953 warning (0, "left shift count >= width of type");
7954 }
7955
7956 /* Use the type of the value to be shifted. */
7957 result_type = type0;
7958 /* Convert the shift-count to an integer, regardless of size
7959 of value being shifted. */
7960 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7961 op1 = convert (integer_type_node, op1);
7962 /* Avoid converting op1 to result_type later. */
7963 converted = 1;
7964 }
7965 break;
7966
7967 case EQ_EXPR:
7968 case NE_EXPR:
7969 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
7970 warning (OPT_Wfloat_equal,
7971 "comparing floating point with == or != is unsafe");
7972 /* Result of comparison is always int,
7973 but don't convert the args to int! */
7974 build_type = integer_type_node;
7975 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7976 || code0 == COMPLEX_TYPE)
7977 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7978 || code1 == COMPLEX_TYPE))
7979 short_compare = 1;
7980 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7981 {
7982 tree tt0 = TREE_TYPE (type0);
7983 tree tt1 = TREE_TYPE (type1);
7984 /* Anything compares with void *. void * compares with anything.
7985 Otherwise, the targets must be compatible
7986 and both must be object or both incomplete. */
7987 if (comp_target_types (type0, type1))
7988 result_type = common_pointer_type (type0, type1);
7989 else if (VOID_TYPE_P (tt0))
7990 {
7991 /* op0 != orig_op0 detects the case of something
7992 whose value is 0 but which isn't a valid null ptr const. */
7993 if (pedantic && !null_pointer_constant_p (orig_op0)
7994 && TREE_CODE (tt1) == FUNCTION_TYPE)
7995 pedwarn ("ISO C forbids comparison of %<void *%>"
7996 " with function pointer");
7997 }
7998 else if (VOID_TYPE_P (tt1))
7999 {
8000 if (pedantic && !null_pointer_constant_p (orig_op1)
8001 && TREE_CODE (tt0) == FUNCTION_TYPE)
8002 pedwarn ("ISO C forbids comparison of %<void *%>"
8003 " with function pointer");
8004 }
8005 else
8006 /* Avoid warning about the volatile ObjC EH puts on decls. */
8007 if (!objc_ok)
8008 pedwarn ("comparison of distinct pointer types lacks a cast");
8009
8010 if (result_type == NULL_TREE)
8011 result_type = ptr_type_node;
8012 }
8013 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
8014 {
8015 if (TREE_CODE (op0) == ADDR_EXPR
8016 && DECL_P (TREE_OPERAND (op0, 0))
8017 && (TREE_CODE (TREE_OPERAND (op0, 0)) == PARM_DECL
8018 || TREE_CODE (TREE_OPERAND (op0, 0)) == LABEL_DECL
8019 || !DECL_WEAK (TREE_OPERAND (op0, 0))))
8020 warning (OPT_Walways_true, "the address of %qD will never be NULL",
8021 TREE_OPERAND (op0, 0));
8022 result_type = type0;
8023 }
8024 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
8025 {
8026 if (TREE_CODE (op1) == ADDR_EXPR
8027 && DECL_P (TREE_OPERAND (op1, 0))
8028 && (TREE_CODE (TREE_OPERAND (op1, 0)) == PARM_DECL
8029 || TREE_CODE (TREE_OPERAND (op1, 0)) == LABEL_DECL
8030 || !DECL_WEAK (TREE_OPERAND (op1, 0))))
8031 warning (OPT_Walways_true, "the address of %qD will never be NULL",
8032 TREE_OPERAND (op1, 0));
8033 result_type = type1;
8034 }
8035 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
8036 {
8037 result_type = type0;
8038 pedwarn ("comparison between pointer and integer");
8039 }
8040 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
8041 {
8042 result_type = type1;
8043 pedwarn ("comparison between pointer and integer");
8044 }
8045 break;
8046
8047 case LE_EXPR:
8048 case GE_EXPR:
8049 case LT_EXPR:
8050 case GT_EXPR:
8051 build_type = integer_type_node;
8052 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
8053 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
8054 short_compare = 1;
8055 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
8056 {
8057 if (comp_target_types (type0, type1))
8058 {
8059 result_type = common_pointer_type (type0, type1);
8060 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
8061 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
8062 pedwarn ("comparison of complete and incomplete pointers");
8063 else if (pedantic
8064 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
8065 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
8066 }
8067 else
8068 {
8069 result_type = ptr_type_node;
8070 pedwarn ("comparison of distinct pointer types lacks a cast");
8071 }
8072 }
8073 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
8074 {
8075 result_type = type0;
8076 if (pedantic || extra_warnings)
8077 pedwarn ("ordered comparison of pointer with integer zero");
8078 }
8079 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
8080 {
8081 result_type = type1;
8082 if (pedantic)
8083 pedwarn ("ordered comparison of pointer with integer zero");
8084 }
8085 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
8086 {
8087 result_type = type0;
8088 pedwarn ("comparison between pointer and integer");
8089 }
8090 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
8091 {
8092 result_type = type1;
8093 pedwarn ("comparison between pointer and integer");
8094 }
8095 break;
8096
8097 default:
8098 gcc_unreachable ();
8099 }
8100
8101 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
8102 return error_mark_node;
8103
8104 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
8105 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
8106 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
8107 TREE_TYPE (type1))))
8108 {
8109 binary_op_error (code);
8110 return error_mark_node;
8111 }
8112
8113 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
8114 || code0 == VECTOR_TYPE)
8115 &&
8116 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
8117 || code1 == VECTOR_TYPE))
8118 {
8119 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
8120
8121 if (shorten || common || short_compare)
8122 result_type = c_common_type (type0, type1);
8123
8124 /* For certain operations (which identify themselves by shorten != 0)
8125 if both args were extended from the same smaller type,
8126 do the arithmetic in that type and then extend.
8127
8128 shorten !=0 and !=1 indicates a bitwise operation.
8129 For them, this optimization is safe only if
8130 both args are zero-extended or both are sign-extended.
8131 Otherwise, we might change the result.
8132 Eg, (short)-1 | (unsigned short)-1 is (int)-1
8133 but calculated in (unsigned short) it would be (unsigned short)-1. */
8134
8135 if (shorten && none_complex)
8136 {
8137 int unsigned0, unsigned1;
8138 tree arg0, arg1;
8139 int uns;
8140 tree type;
8141
8142 /* Cast OP0 and OP1 to RESULT_TYPE. Doing so prevents
8143 excessive narrowing when we call get_narrower below. For
8144 example, suppose that OP0 is of unsigned int extended
8145 from signed char and that RESULT_TYPE is long long int.
8146 If we explicitly cast OP0 to RESULT_TYPE, OP0 would look
8147 like
8148
8149 (long long int) (unsigned int) signed_char
8150
8151 which get_narrower would narrow down to
8152
8153 (unsigned int) signed char
8154
8155 If we do not cast OP0 first, get_narrower would return
8156 signed_char, which is inconsistent with the case of the
8157 explicit cast. */
8158 op0 = convert (result_type, op0);
8159 op1 = convert (result_type, op1);
8160
8161 arg0 = get_narrower (op0, &unsigned0);
8162 arg1 = get_narrower (op1, &unsigned1);
8163
8164 /* UNS is 1 if the operation to be done is an unsigned one. */
8165 uns = TYPE_UNSIGNED (result_type);
8166
8167 final_type = result_type;
8168
8169 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
8170 but it *requires* conversion to FINAL_TYPE. */
8171
8172 if ((TYPE_PRECISION (TREE_TYPE (op0))
8173 == TYPE_PRECISION (TREE_TYPE (arg0)))
8174 && TREE_TYPE (op0) != final_type)
8175 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
8176 if ((TYPE_PRECISION (TREE_TYPE (op1))
8177 == TYPE_PRECISION (TREE_TYPE (arg1)))
8178 && TREE_TYPE (op1) != final_type)
8179 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
8180
8181 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
8182
8183 /* For bitwise operations, signedness of nominal type
8184 does not matter. Consider only how operands were extended. */
8185 if (shorten == -1)
8186 uns = unsigned0;
8187
8188 /* Note that in all three cases below we refrain from optimizing
8189 an unsigned operation on sign-extended args.
8190 That would not be valid. */
8191
8192 /* Both args variable: if both extended in same way
8193 from same width, do it in that width.
8194 Do it unsigned if args were zero-extended. */
8195 if ((TYPE_PRECISION (TREE_TYPE (arg0))
8196 < TYPE_PRECISION (result_type))
8197 && (TYPE_PRECISION (TREE_TYPE (arg1))
8198 == TYPE_PRECISION (TREE_TYPE (arg0)))
8199 && unsigned0 == unsigned1
8200 && (unsigned0 || !uns))
8201 result_type
8202 = c_common_signed_or_unsigned_type
8203 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
8204 else if (TREE_CODE (arg0) == INTEGER_CST
8205 && (unsigned1 || !uns)
8206 && (TYPE_PRECISION (TREE_TYPE (arg1))
8207 < TYPE_PRECISION (result_type))
8208 && (type
8209 = c_common_signed_or_unsigned_type (unsigned1,
8210 TREE_TYPE (arg1)),
8211 int_fits_type_p (arg0, type)))
8212 result_type = type;
8213 else if (TREE_CODE (arg1) == INTEGER_CST
8214 && (unsigned0 || !uns)
8215 && (TYPE_PRECISION (TREE_TYPE (arg0))
8216 < TYPE_PRECISION (result_type))
8217 && (type
8218 = c_common_signed_or_unsigned_type (unsigned0,
8219 TREE_TYPE (arg0)),
8220 int_fits_type_p (arg1, type)))
8221 result_type = type;
8222 }
8223
8224 /* Shifts can be shortened if shifting right. */
8225
8226 if (short_shift)
8227 {
8228 int unsigned_arg;
8229 tree arg0 = get_narrower (op0, &unsigned_arg);
8230
8231 final_type = result_type;
8232
8233 if (arg0 == op0 && final_type == TREE_TYPE (op0))
8234 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
8235
8236 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
8237 /* We can shorten only if the shift count is less than the
8238 number of bits in the smaller type size. */
8239 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
8240 /* We cannot drop an unsigned shift after sign-extension. */
8241 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
8242 {
8243 /* Do an unsigned shift if the operand was zero-extended. */
8244 result_type
8245 = c_common_signed_or_unsigned_type (unsigned_arg,
8246 TREE_TYPE (arg0));
8247 /* Convert value-to-be-shifted to that type. */
8248 if (TREE_TYPE (op0) != result_type)
8249 op0 = convert (result_type, op0);
8250 converted = 1;
8251 }
8252 }
8253
8254 /* Comparison operations are shortened too but differently.
8255 They identify themselves by setting short_compare = 1. */
8256
8257 if (short_compare)
8258 {
8259 /* Don't write &op0, etc., because that would prevent op0
8260 from being kept in a register.
8261 Instead, make copies of the our local variables and
8262 pass the copies by reference, then copy them back afterward. */
8263 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
8264 enum tree_code xresultcode = resultcode;
8265 tree val
8266 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
8267
8268 if (val != 0)
8269 return val;
8270
8271 op0 = xop0, op1 = xop1;
8272 converted = 1;
8273 resultcode = xresultcode;
8274
8275 if (warn_sign_compare && skip_evaluation == 0)
8276 {
8277 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
8278 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
8279 int unsignedp0, unsignedp1;
8280 tree primop0 = get_narrower (op0, &unsignedp0);
8281 tree primop1 = get_narrower (op1, &unsignedp1);
8282
8283 xop0 = orig_op0;
8284 xop1 = orig_op1;
8285 STRIP_TYPE_NOPS (xop0);
8286 STRIP_TYPE_NOPS (xop1);
8287
8288 /* Give warnings for comparisons between signed and unsigned
8289 quantities that may fail.
8290
8291 Do the checking based on the original operand trees, so that
8292 casts will be considered, but default promotions won't be.
8293
8294 Do not warn if the comparison is being done in a signed type,
8295 since the signed type will only be chosen if it can represent
8296 all the values of the unsigned type. */
8297 if (!TYPE_UNSIGNED (result_type))
8298 /* OK */;
8299 /* Do not warn if both operands are the same signedness. */
8300 else if (op0_signed == op1_signed)
8301 /* OK */;
8302 else
8303 {
8304 tree sop, uop;
8305
8306 if (op0_signed)
8307 sop = xop0, uop = xop1;
8308 else
8309 sop = xop1, uop = xop0;
8310
8311 /* Do not warn if the signed quantity is an
8312 unsuffixed integer literal (or some static
8313 constant expression involving such literals or a
8314 conditional expression involving such literals)
8315 and it is non-negative. */
8316 if (tree_expr_nonnegative_p (sop))
8317 /* OK */;
8318 /* Do not warn if the comparison is an equality operation,
8319 the unsigned quantity is an integral constant, and it
8320 would fit in the result if the result were signed. */
8321 else if (TREE_CODE (uop) == INTEGER_CST
8322 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
8323 && int_fits_type_p
8324 (uop, c_common_signed_type (result_type)))
8325 /* OK */;
8326 /* Do not warn if the unsigned quantity is an enumeration
8327 constant and its maximum value would fit in the result
8328 if the result were signed. */
8329 else if (TREE_CODE (uop) == INTEGER_CST
8330 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
8331 && int_fits_type_p
8332 (TYPE_MAX_VALUE (TREE_TYPE (uop)),
8333 c_common_signed_type (result_type)))
8334 /* OK */;
8335 else
8336 warning (0, "comparison between signed and unsigned");
8337 }
8338
8339 /* Warn if two unsigned values are being compared in a size
8340 larger than their original size, and one (and only one) is the
8341 result of a `~' operator. This comparison will always fail.
8342
8343 Also warn if one operand is a constant, and the constant
8344 does not have all bits set that are set in the ~ operand
8345 when it is extended. */
8346
8347 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
8348 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
8349 {
8350 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
8351 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
8352 &unsignedp0);
8353 else
8354 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
8355 &unsignedp1);
8356
8357 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
8358 {
8359 tree primop;
8360 HOST_WIDE_INT constant, mask;
8361 int unsignedp, bits;
8362
8363 if (host_integerp (primop0, 0))
8364 {
8365 primop = primop1;
8366 unsignedp = unsignedp1;
8367 constant = tree_low_cst (primop0, 0);
8368 }
8369 else
8370 {
8371 primop = primop0;
8372 unsignedp = unsignedp0;
8373 constant = tree_low_cst (primop1, 0);
8374 }
8375
8376 bits = TYPE_PRECISION (TREE_TYPE (primop));
8377 if (bits < TYPE_PRECISION (result_type)
8378 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
8379 {
8380 mask = (~(HOST_WIDE_INT) 0) << bits;
8381 if ((mask & constant) != mask)
8382 warning (0, "comparison of promoted ~unsigned with constant");
8383 }
8384 }
8385 else if (unsignedp0 && unsignedp1
8386 && (TYPE_PRECISION (TREE_TYPE (primop0))
8387 < TYPE_PRECISION (result_type))
8388 && (TYPE_PRECISION (TREE_TYPE (primop1))
8389 < TYPE_PRECISION (result_type)))
8390 warning (0, "comparison of promoted ~unsigned with unsigned");
8391 }
8392 }
8393 }
8394 }
8395
8396 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
8397 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
8398 Then the expression will be built.
8399 It will be given type FINAL_TYPE if that is nonzero;
8400 otherwise, it will be given type RESULT_TYPE. */
8401
8402 if (!result_type)
8403 {
8404 binary_op_error (code);
8405 return error_mark_node;
8406 }
8407
8408 if (!converted)
8409 {
8410 if (TREE_TYPE (op0) != result_type)
8411 op0 = convert_and_check (result_type, op0);
8412 if (TREE_TYPE (op1) != result_type)
8413 op1 = convert_and_check (result_type, op1);
8414
8415 /* This can happen if one operand has a vector type, and the other
8416 has a different type. */
8417 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
8418 return error_mark_node;
8419 }
8420
8421 if (build_type == NULL_TREE)
8422 build_type = result_type;
8423
8424 {
8425 /* Treat expressions in initializers specially as they can't trap. */
8426 tree result = require_constant_value ? fold_build2_initializer (resultcode,
8427 build_type,
8428 op0, op1)
8429 : fold_build2 (resultcode, build_type,
8430 op0, op1);
8431
8432 if (final_type != 0)
8433 result = convert (final_type, result);
8434 return result;
8435 }
8436 }
8437
8438
8439 /* Convert EXPR to be a truth-value, validating its type for this
8440 purpose. */
8441
8442 tree
8443 c_objc_common_truthvalue_conversion (tree expr)
8444 {
8445 switch (TREE_CODE (TREE_TYPE (expr)))
8446 {
8447 case ARRAY_TYPE:
8448 error ("used array that cannot be converted to pointer where scalar is required");
8449 return error_mark_node;
8450
8451 case RECORD_TYPE:
8452 error ("used struct type value where scalar is required");
8453 return error_mark_node;
8454
8455 case UNION_TYPE:
8456 error ("used union type value where scalar is required");
8457 return error_mark_node;
8458
8459 case FUNCTION_TYPE:
8460 gcc_unreachable ();
8461
8462 default:
8463 break;
8464 }
8465
8466 /* ??? Should we also give an error for void and vectors rather than
8467 leaving those to give errors later? */
8468 return c_common_truthvalue_conversion (expr);
8469 }
8470 \f
8471
8472 /* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as
8473 required. */
8474
8475 tree
8476 c_expr_to_decl (tree expr, bool *tc ATTRIBUTE_UNUSED,
8477 bool *ti ATTRIBUTE_UNUSED, bool *se)
8478 {
8479 if (TREE_CODE (expr) == COMPOUND_LITERAL_EXPR)
8480 {
8481 tree decl = COMPOUND_LITERAL_EXPR_DECL (expr);
8482 /* Executing a compound literal inside a function reinitializes
8483 it. */
8484 if (!TREE_STATIC (decl))
8485 *se = true;
8486 return decl;
8487 }
8488 else
8489 return expr;
8490 }
8491 \f
8492 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
8493
8494 tree
8495 c_begin_omp_parallel (void)
8496 {
8497 tree block;
8498
8499 keep_next_level ();
8500 block = c_begin_compound_stmt (true);
8501
8502 return block;
8503 }
8504
8505 tree
8506 c_finish_omp_parallel (tree clauses, tree block)
8507 {
8508 tree stmt;
8509
8510 block = c_end_compound_stmt (block, true);
8511
8512 stmt = make_node (OMP_PARALLEL);
8513 TREE_TYPE (stmt) = void_type_node;
8514 OMP_PARALLEL_CLAUSES (stmt) = clauses;
8515 OMP_PARALLEL_BODY (stmt) = block;
8516
8517 return add_stmt (stmt);
8518 }
8519
8520 /* For all elements of CLAUSES, validate them vs OpenMP constraints.
8521 Remove any elements from the list that are invalid. */
8522
8523 tree
8524 c_finish_omp_clauses (tree clauses)
8525 {
8526 bitmap_head generic_head, firstprivate_head, lastprivate_head;
8527 tree c, t, *pc = &clauses;
8528 const char *name;
8529
8530 bitmap_obstack_initialize (NULL);
8531 bitmap_initialize (&generic_head, &bitmap_default_obstack);
8532 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack);
8533 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack);
8534
8535 for (pc = &clauses, c = clauses; c ; c = *pc)
8536 {
8537 bool remove = false;
8538 bool need_complete = false;
8539 bool need_implicitly_determined = false;
8540
8541 switch (OMP_CLAUSE_CODE (c))
8542 {
8543 case OMP_CLAUSE_SHARED:
8544 name = "shared";
8545 need_implicitly_determined = true;
8546 goto check_dup_generic;
8547
8548 case OMP_CLAUSE_PRIVATE:
8549 name = "private";
8550 need_complete = true;
8551 need_implicitly_determined = true;
8552 goto check_dup_generic;
8553
8554 case OMP_CLAUSE_REDUCTION:
8555 name = "reduction";
8556 need_implicitly_determined = true;
8557 t = OMP_CLAUSE_DECL (c);
8558 if (AGGREGATE_TYPE_P (TREE_TYPE (t))
8559 || POINTER_TYPE_P (TREE_TYPE (t)))
8560 {
8561 error ("%qE has invalid type for %<reduction%>", t);
8562 remove = true;
8563 }
8564 else if (FLOAT_TYPE_P (TREE_TYPE (t)))
8565 {
8566 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c);
8567 const char *r_name = NULL;
8568
8569 switch (r_code)
8570 {
8571 case PLUS_EXPR:
8572 case MULT_EXPR:
8573 case MINUS_EXPR:
8574 break;
8575 case BIT_AND_EXPR:
8576 r_name = "&";
8577 break;
8578 case BIT_XOR_EXPR:
8579 r_name = "^";
8580 break;
8581 case BIT_IOR_EXPR:
8582 r_name = "|";
8583 break;
8584 case TRUTH_ANDIF_EXPR:
8585 r_name = "&&";
8586 break;
8587 case TRUTH_ORIF_EXPR:
8588 r_name = "||";
8589 break;
8590 default:
8591 gcc_unreachable ();
8592 }
8593 if (r_name)
8594 {
8595 error ("%qE has invalid type for %<reduction(%s)%>",
8596 t, r_name);
8597 remove = true;
8598 }
8599 }
8600 goto check_dup_generic;
8601
8602 case OMP_CLAUSE_COPYPRIVATE:
8603 name = "copyprivate";
8604 goto check_dup_generic;
8605
8606 case OMP_CLAUSE_COPYIN:
8607 name = "copyin";
8608 t = OMP_CLAUSE_DECL (c);
8609 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t))
8610 {
8611 error ("%qE must be %<threadprivate%> for %<copyin%>", t);
8612 remove = true;
8613 }
8614 goto check_dup_generic;
8615
8616 check_dup_generic:
8617 t = OMP_CLAUSE_DECL (c);
8618 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8619 {
8620 error ("%qE is not a variable in clause %qs", t, name);
8621 remove = true;
8622 }
8623 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8624 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))
8625 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
8626 {
8627 error ("%qE appears more than once in data clauses", t);
8628 remove = true;
8629 }
8630 else
8631 bitmap_set_bit (&generic_head, DECL_UID (t));
8632 break;
8633
8634 case OMP_CLAUSE_FIRSTPRIVATE:
8635 name = "firstprivate";
8636 t = OMP_CLAUSE_DECL (c);
8637 need_complete = true;
8638 need_implicitly_determined = true;
8639 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8640 {
8641 error ("%qE is not a variable in clause %<firstprivate%>", t);
8642 remove = true;
8643 }
8644 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8645 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)))
8646 {
8647 error ("%qE appears more than once in data clauses", t);
8648 remove = true;
8649 }
8650 else
8651 bitmap_set_bit (&firstprivate_head, DECL_UID (t));
8652 break;
8653
8654 case OMP_CLAUSE_LASTPRIVATE:
8655 name = "lastprivate";
8656 t = OMP_CLAUSE_DECL (c);
8657 need_complete = true;
8658 need_implicitly_determined = true;
8659 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8660 {
8661 error ("%qE is not a variable in clause %<lastprivate%>", t);
8662 remove = true;
8663 }
8664 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8665 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
8666 {
8667 error ("%qE appears more than once in data clauses", t);
8668 remove = true;
8669 }
8670 else
8671 bitmap_set_bit (&lastprivate_head, DECL_UID (t));
8672 break;
8673
8674 case OMP_CLAUSE_IF:
8675 case OMP_CLAUSE_NUM_THREADS:
8676 case OMP_CLAUSE_SCHEDULE:
8677 case OMP_CLAUSE_NOWAIT:
8678 case OMP_CLAUSE_ORDERED:
8679 case OMP_CLAUSE_DEFAULT:
8680 pc = &OMP_CLAUSE_CHAIN (c);
8681 continue;
8682
8683 default:
8684 gcc_unreachable ();
8685 }
8686
8687 if (!remove)
8688 {
8689 t = OMP_CLAUSE_DECL (c);
8690
8691 if (need_complete)
8692 {
8693 t = require_complete_type (t);
8694 if (t == error_mark_node)
8695 remove = true;
8696 }
8697
8698 if (need_implicitly_determined)
8699 {
8700 const char *share_name = NULL;
8701
8702 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t))
8703 share_name = "threadprivate";
8704 else switch (c_omp_predetermined_sharing (t))
8705 {
8706 case OMP_CLAUSE_DEFAULT_UNSPECIFIED:
8707 break;
8708 case OMP_CLAUSE_DEFAULT_SHARED:
8709 share_name = "shared";
8710 break;
8711 case OMP_CLAUSE_DEFAULT_PRIVATE:
8712 share_name = "private";
8713 break;
8714 default:
8715 gcc_unreachable ();
8716 }
8717 if (share_name)
8718 {
8719 error ("%qE is predetermined %qs for %qs",
8720 t, share_name, name);
8721 remove = true;
8722 }
8723 }
8724 }
8725
8726 if (remove)
8727 *pc = OMP_CLAUSE_CHAIN (c);
8728 else
8729 pc = &OMP_CLAUSE_CHAIN (c);
8730 }
8731
8732 bitmap_obstack_release (NULL);
8733 return clauses;
8734 }
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