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gcc/ChangeLog ---------------------------------------------------------
[official-gcc.git] / gcc / c-typeck.c
blobd3495a9f71dec39cf0a94330f94941246781c05e
1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
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_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_build_call_list_initializer (TREE_TYPE (fntype),
2334 function,
2335 coerced_params);
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_build_call_list (TREE_TYPE (fntype),
2343 function, coerced_params);
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
2605 if (TREE_OVERFLOW_P (result.value) && !TREE_OVERFLOW_P (arg.value))
2606 overflow_warning (result.value);
2607
2608 return result;
2609 }
2610
2611 /* This is the entry point used by the parser to build binary operators
2612 in the input. CODE, a tree_code, specifies the binary operator, and
2613 ARG1 and ARG2 are the operands. In addition to constructing the
2614 expression, we check for operands that were written with other binary
2615 operators in a way that is likely to confuse the user. */
2616
2617 struct c_expr
2618 parser_build_binary_op (enum tree_code code, struct c_expr arg1,
2619 struct c_expr arg2)
2620 {
2621 struct c_expr result;
2622
2623 enum tree_code code1 = arg1.original_code;
2624 enum tree_code code2 = arg2.original_code;
2625
2626 result.value = build_binary_op (code, arg1.value, arg2.value, 1);
2627 result.original_code = code;
2628
2629 if (TREE_CODE (result.value) == ERROR_MARK)
2630 return result;
2631
2632 /* Check for cases such as x+y<<z which users are likely
2633 to misinterpret. */
2634 if (warn_parentheses)
2635 warn_about_parentheses (code, code1, code2);
2636
2637 /* Warn about comparisons against string literals, with the exception
2638 of testing for equality or inequality of a string literal with NULL. */
2639 if (code == EQ_EXPR || code == NE_EXPR)
2640 {
2641 if ((code1 == STRING_CST && !integer_zerop (arg2.value))
2642 || (code2 == STRING_CST && !integer_zerop (arg1.value)))
2643 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
2644 }
2645 else if (TREE_CODE_CLASS (code) == tcc_comparison
2646 && (code1 == STRING_CST || code2 == STRING_CST))
2647 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
2648
2649 if (TREE_OVERFLOW_P (result.value)
2650 && !TREE_OVERFLOW_P (arg1.value)
2651 && !TREE_OVERFLOW_P (arg2.value))
2652 overflow_warning (result.value);
2653
2654 return result;
2655 }
2656 \f
2657 /* Return a tree for the difference of pointers OP0 and OP1.
2658 The resulting tree has type int. */
2659
2660 static tree
2661 pointer_diff (tree op0, tree op1)
2662 {
2663 tree restype = ptrdiff_type_node;
2664
2665 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2666 tree con0, con1, lit0, lit1;
2667 tree orig_op1 = op1;
2668
2669 if (pedantic || warn_pointer_arith)
2670 {
2671 if (TREE_CODE (target_type) == VOID_TYPE)
2672 pedwarn ("pointer of type %<void *%> used in subtraction");
2673 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2674 pedwarn ("pointer to a function used in subtraction");
2675 }
2676
2677 /* If the conversion to ptrdiff_type does anything like widening or
2678 converting a partial to an integral mode, we get a convert_expression
2679 that is in the way to do any simplifications.
2680 (fold-const.c doesn't know that the extra bits won't be needed.
2681 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2682 different mode in place.)
2683 So first try to find a common term here 'by hand'; we want to cover
2684 at least the cases that occur in legal static initializers. */
2685 if ((TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == CONVERT_EXPR)
2686 && (TYPE_PRECISION (TREE_TYPE (op0))
2687 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
2688 con0 = TREE_OPERAND (op0, 0);
2689 else
2690 con0 = op0;
2691 if ((TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == CONVERT_EXPR)
2692 && (TYPE_PRECISION (TREE_TYPE (op1))
2693 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))))
2694 con1 = TREE_OPERAND (op1, 0);
2695 else
2696 con1 = op1;
2697
2698 if (TREE_CODE (con0) == PLUS_EXPR)
2699 {
2700 lit0 = TREE_OPERAND (con0, 1);
2701 con0 = TREE_OPERAND (con0, 0);
2702 }
2703 else
2704 lit0 = integer_zero_node;
2705
2706 if (TREE_CODE (con1) == PLUS_EXPR)
2707 {
2708 lit1 = TREE_OPERAND (con1, 1);
2709 con1 = TREE_OPERAND (con1, 0);
2710 }
2711 else
2712 lit1 = integer_zero_node;
2713
2714 if (operand_equal_p (con0, con1, 0))
2715 {
2716 op0 = lit0;
2717 op1 = lit1;
2718 }
2719
2720
2721 /* First do the subtraction as integers;
2722 then drop through to build the divide operator.
2723 Do not do default conversions on the minus operator
2724 in case restype is a short type. */
2725
2726 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2727 convert (restype, op1), 0);
2728 /* This generates an error if op1 is pointer to incomplete type. */
2729 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
2730 error ("arithmetic on pointer to an incomplete type");
2731
2732 /* This generates an error if op0 is pointer to incomplete type. */
2733 op1 = c_size_in_bytes (target_type);
2734
2735 /* Divide by the size, in easiest possible way. */
2736 return fold_build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2737 }
2738 \f
2739 /* Construct and perhaps optimize a tree representation
2740 for a unary operation. CODE, a tree_code, specifies the operation
2741 and XARG is the operand.
2742 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2743 the default promotions (such as from short to int).
2744 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2745 allows non-lvalues; this is only used to handle conversion of non-lvalue
2746 arrays to pointers in C99. */
2747
2748 tree
2749 build_unary_op (enum tree_code code, tree xarg, int flag)
2750 {
2751 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2752 tree arg = xarg;
2753 tree argtype = 0;
2754 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2755 tree val;
2756 int noconvert = flag;
2757 const char *invalid_op_diag;
2758
2759 if (typecode == ERROR_MARK)
2760 return error_mark_node;
2761 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2762 typecode = INTEGER_TYPE;
2763
2764 if ((invalid_op_diag
2765 = targetm.invalid_unary_op (code, TREE_TYPE (xarg))))
2766 {
2767 error (invalid_op_diag);
2768 return error_mark_node;
2769 }
2770
2771 switch (code)
2772 {
2773 case CONVERT_EXPR:
2774 /* This is used for unary plus, because a CONVERT_EXPR
2775 is enough to prevent anybody from looking inside for
2776 associativity, but won't generate any code. */
2777 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2778 || typecode == COMPLEX_TYPE
2779 || typecode == VECTOR_TYPE))
2780 {
2781 error ("wrong type argument to unary plus");
2782 return error_mark_node;
2783 }
2784 else if (!noconvert)
2785 arg = default_conversion (arg);
2786 arg = non_lvalue (arg);
2787 break;
2788
2789 case NEGATE_EXPR:
2790 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2791 || typecode == COMPLEX_TYPE
2792 || typecode == VECTOR_TYPE))
2793 {
2794 error ("wrong type argument to unary minus");
2795 return error_mark_node;
2796 }
2797 else if (!noconvert)
2798 arg = default_conversion (arg);
2799 break;
2800
2801 case BIT_NOT_EXPR:
2802 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE)
2803 {
2804 if (!noconvert)
2805 arg = default_conversion (arg);
2806 }
2807 else if (typecode == COMPLEX_TYPE)
2808 {
2809 code = CONJ_EXPR;
2810 if (pedantic)
2811 pedwarn ("ISO C does not support %<~%> for complex conjugation");
2812 if (!noconvert)
2813 arg = default_conversion (arg);
2814 }
2815 else
2816 {
2817 error ("wrong type argument to bit-complement");
2818 return error_mark_node;
2819 }
2820 break;
2821
2822 case ABS_EXPR:
2823 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
2824 {
2825 error ("wrong type argument to abs");
2826 return error_mark_node;
2827 }
2828 else if (!noconvert)
2829 arg = default_conversion (arg);
2830 break;
2831
2832 case CONJ_EXPR:
2833 /* Conjugating a real value is a no-op, but allow it anyway. */
2834 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2835 || typecode == COMPLEX_TYPE))
2836 {
2837 error ("wrong type argument to conjugation");
2838 return error_mark_node;
2839 }
2840 else if (!noconvert)
2841 arg = default_conversion (arg);
2842 break;
2843
2844 case TRUTH_NOT_EXPR:
2845 if (typecode != INTEGER_TYPE
2846 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2847 && typecode != COMPLEX_TYPE)
2848 {
2849 error ("wrong type argument to unary exclamation mark");
2850 return error_mark_node;
2851 }
2852 arg = c_objc_common_truthvalue_conversion (arg);
2853 return invert_truthvalue (arg);
2854
2855 case REALPART_EXPR:
2856 if (TREE_CODE (arg) == COMPLEX_CST)
2857 return TREE_REALPART (arg);
2858 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2859 return fold_build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
2860 else
2861 return arg;
2862
2863 case IMAGPART_EXPR:
2864 if (TREE_CODE (arg) == COMPLEX_CST)
2865 return TREE_IMAGPART (arg);
2866 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2867 return fold_build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
2868 else
2869 return convert (TREE_TYPE (arg), integer_zero_node);
2870
2871 case PREINCREMENT_EXPR:
2872 case POSTINCREMENT_EXPR:
2873 case PREDECREMENT_EXPR:
2874 case POSTDECREMENT_EXPR:
2875
2876 /* Increment or decrement the real part of the value,
2877 and don't change the imaginary part. */
2878 if (typecode == COMPLEX_TYPE)
2879 {
2880 tree real, imag;
2881
2882 if (pedantic)
2883 pedwarn ("ISO C does not support %<++%> and %<--%>"
2884 " on complex types");
2885
2886 arg = stabilize_reference (arg);
2887 real = build_unary_op (REALPART_EXPR, arg, 1);
2888 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2889 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
2890 build_unary_op (code, real, 1), imag);
2891 }
2892
2893 /* Report invalid types. */
2894
2895 if (typecode != POINTER_TYPE
2896 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2897 {
2898 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2899 error ("wrong type argument to increment");
2900 else
2901 error ("wrong type argument to decrement");
2902
2903 return error_mark_node;
2904 }
2905
2906 {
2907 tree inc;
2908 tree result_type = TREE_TYPE (arg);
2909
2910 arg = get_unwidened (arg, 0);
2911 argtype = TREE_TYPE (arg);
2912
2913 /* Compute the increment. */
2914
2915 if (typecode == POINTER_TYPE)
2916 {
2917 /* If pointer target is an undefined struct,
2918 we just cannot know how to do the arithmetic. */
2919 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2920 {
2921 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2922 error ("increment of pointer to unknown structure");
2923 else
2924 error ("decrement of pointer to unknown structure");
2925 }
2926 else if ((pedantic || warn_pointer_arith)
2927 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2928 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2929 {
2930 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2931 pedwarn ("wrong type argument to increment");
2932 else
2933 pedwarn ("wrong type argument to decrement");
2934 }
2935
2936 inc = c_size_in_bytes (TREE_TYPE (result_type));
2937 }
2938 else
2939 inc = integer_one_node;
2940
2941 inc = convert (argtype, inc);
2942
2943 /* Complain about anything else that is not a true lvalue. */
2944 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2945 || code == POSTINCREMENT_EXPR)
2946 ? lv_increment
2947 : lv_decrement)))
2948 return error_mark_node;
2949
2950 /* Report a read-only lvalue. */
2951 if (TREE_READONLY (arg))
2952 {
2953 readonly_error (arg,
2954 ((code == PREINCREMENT_EXPR
2955 || code == POSTINCREMENT_EXPR)
2956 ? lv_increment : lv_decrement));
2957 return error_mark_node;
2958 }
2959
2960 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
2961 val = boolean_increment (code, arg);
2962 else
2963 val = build2 (code, TREE_TYPE (arg), arg, inc);
2964 TREE_SIDE_EFFECTS (val) = 1;
2965 val = convert (result_type, val);
2966 if (TREE_CODE (val) != code)
2967 TREE_NO_WARNING (val) = 1;
2968 return val;
2969 }
2970
2971 case ADDR_EXPR:
2972 /* Note that this operation never does default_conversion. */
2973
2974 /* Let &* cancel out to simplify resulting code. */
2975 if (TREE_CODE (arg) == INDIRECT_REF)
2976 {
2977 /* Don't let this be an lvalue. */
2978 if (lvalue_p (TREE_OPERAND (arg, 0)))
2979 return non_lvalue (TREE_OPERAND (arg, 0));
2980 return TREE_OPERAND (arg, 0);
2981 }
2982
2983 /* For &x[y], return x+y */
2984 if (TREE_CODE (arg) == ARRAY_REF)
2985 {
2986 tree op0 = TREE_OPERAND (arg, 0);
2987 if (!c_mark_addressable (op0))
2988 return error_mark_node;
2989 return build_binary_op (PLUS_EXPR,
2990 (TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE
2991 ? array_to_pointer_conversion (op0)
2992 : op0),
2993 TREE_OPERAND (arg, 1), 1);
2994 }
2995
2996 /* Anything not already handled and not a true memory reference
2997 or a non-lvalue array is an error. */
2998 else if (typecode != FUNCTION_TYPE && !flag
2999 && !lvalue_or_else (arg, lv_addressof))
3000 return error_mark_node;
3001
3002 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3003 argtype = TREE_TYPE (arg);
3004
3005 /* If the lvalue is const or volatile, merge that into the type
3006 to which the address will point. Note that you can't get a
3007 restricted pointer by taking the address of something, so we
3008 only have to deal with `const' and `volatile' here. */
3009 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
3010 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
3011 argtype = c_build_type_variant (argtype,
3012 TREE_READONLY (arg),
3013 TREE_THIS_VOLATILE (arg));
3014
3015 if (!c_mark_addressable (arg))
3016 return error_mark_node;
3017
3018 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
3019 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
3020
3021 argtype = build_pointer_type (argtype);
3022
3023 /* ??? Cope with user tricks that amount to offsetof. Delete this
3024 when we have proper support for integer constant expressions. */
3025 val = get_base_address (arg);
3026 if (val && TREE_CODE (val) == INDIRECT_REF
3027 && TREE_CONSTANT (TREE_OPERAND (val, 0)))
3028 {
3029 tree op0 = fold_convert (argtype, fold_offsetof (arg, val)), op1;
3030
3031 op1 = fold_convert (argtype, TREE_OPERAND (val, 0));
3032 return fold_build2 (PLUS_EXPR, argtype, op0, op1);
3033 }
3034
3035 val = build1 (ADDR_EXPR, argtype, arg);
3036
3037 return val;
3038
3039 default:
3040 gcc_unreachable ();
3041 }
3042
3043 if (argtype == 0)
3044 argtype = TREE_TYPE (arg);
3045 return require_constant_value ? fold_build1_initializer (code, argtype, arg)
3046 : fold_build1 (code, argtype, arg);
3047 }
3048
3049 /* Return nonzero if REF is an lvalue valid for this language.
3050 Lvalues can be assigned, unless their type has TYPE_READONLY.
3051 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
3052
3053 static int
3054 lvalue_p (tree ref)
3055 {
3056 enum tree_code code = TREE_CODE (ref);
3057
3058 switch (code)
3059 {
3060 case REALPART_EXPR:
3061 case IMAGPART_EXPR:
3062 case COMPONENT_REF:
3063 return lvalue_p (TREE_OPERAND (ref, 0));
3064
3065 case COMPOUND_LITERAL_EXPR:
3066 case STRING_CST:
3067 return 1;
3068
3069 case INDIRECT_REF:
3070 case ARRAY_REF:
3071 case VAR_DECL:
3072 case PARM_DECL:
3073 case RESULT_DECL:
3074 case ERROR_MARK:
3075 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3076 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3077
3078 case BIND_EXPR:
3079 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3080
3081 default:
3082 return 0;
3083 }
3084 }
3085 \f
3086 /* Give an error for storing in something that is 'const'. */
3087
3088 static void
3089 readonly_error (tree arg, enum lvalue_use use)
3090 {
3091 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement
3092 || use == lv_asm);
3093 /* Using this macro rather than (for example) arrays of messages
3094 ensures that all the format strings are checked at compile
3095 time. */
3096 #define READONLY_MSG(A, I, D, AS) (use == lv_assign ? (A) \
3097 : (use == lv_increment ? (I) \
3098 : (use == lv_decrement ? (D) : (AS))))
3099 if (TREE_CODE (arg) == COMPONENT_REF)
3100 {
3101 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3102 readonly_error (TREE_OPERAND (arg, 0), use);
3103 else
3104 error (READONLY_MSG (G_("assignment of read-only member %qD"),
3105 G_("increment of read-only member %qD"),
3106 G_("decrement of read-only member %qD"),
3107 G_("read-only member %qD used as %<asm%> output")),
3108 TREE_OPERAND (arg, 1));
3109 }
3110 else if (TREE_CODE (arg) == VAR_DECL)
3111 error (READONLY_MSG (G_("assignment of read-only variable %qD"),
3112 G_("increment of read-only variable %qD"),
3113 G_("decrement of read-only variable %qD"),
3114 G_("read-only variable %qD used as %<asm%> output")),
3115 arg);
3116 else
3117 error (READONLY_MSG (G_("assignment of read-only location"),
3118 G_("increment of read-only location"),
3119 G_("decrement of read-only location"),
3120 G_("read-only location used as %<asm%> output")));
3121 }
3122
3123
3124 /* Return nonzero if REF is an lvalue valid for this language;
3125 otherwise, print an error message and return zero. USE says
3126 how the lvalue is being used and so selects the error message. */
3127
3128 static int
3129 lvalue_or_else (tree ref, enum lvalue_use use)
3130 {
3131 int win = lvalue_p (ref);
3132
3133 if (!win)
3134 lvalue_error (use);
3135
3136 return win;
3137 }
3138 \f
3139 /* Mark EXP saying that we need to be able to take the
3140 address of it; it should not be allocated in a register.
3141 Returns true if successful. */
3142
3143 bool
3144 c_mark_addressable (tree exp)
3145 {
3146 tree x = exp;
3147
3148 while (1)
3149 switch (TREE_CODE (x))
3150 {
3151 case COMPONENT_REF:
3152 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3153 {
3154 error
3155 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
3156 return false;
3157 }
3158
3159 /* ... fall through ... */
3160
3161 case ADDR_EXPR:
3162 case ARRAY_REF:
3163 case REALPART_EXPR:
3164 case IMAGPART_EXPR:
3165 x = TREE_OPERAND (x, 0);
3166 break;
3167
3168 case COMPOUND_LITERAL_EXPR:
3169 case CONSTRUCTOR:
3170 TREE_ADDRESSABLE (x) = 1;
3171 return true;
3172
3173 case VAR_DECL:
3174 case CONST_DECL:
3175 case PARM_DECL:
3176 case RESULT_DECL:
3177 if (C_DECL_REGISTER (x)
3178 && DECL_NONLOCAL (x))
3179 {
3180 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3181 {
3182 error
3183 ("global register variable %qD used in nested function", x);
3184 return false;
3185 }
3186 pedwarn ("register variable %qD used in nested function", x);
3187 }
3188 else if (C_DECL_REGISTER (x))
3189 {
3190 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3191 error ("address of global register variable %qD requested", x);
3192 else
3193 error ("address of register variable %qD requested", x);
3194 return false;
3195 }
3196
3197 /* drops in */
3198 case FUNCTION_DECL:
3199 TREE_ADDRESSABLE (x) = 1;
3200 /* drops out */
3201 default:
3202 return true;
3203 }
3204 }
3205 \f
3206 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3207
3208 tree
3209 build_conditional_expr (tree ifexp, tree op1, tree op2)
3210 {
3211 tree type1;
3212 tree type2;
3213 enum tree_code code1;
3214 enum tree_code code2;
3215 tree result_type = NULL;
3216 tree orig_op1 = op1, orig_op2 = op2;
3217
3218 /* Promote both alternatives. */
3219
3220 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3221 op1 = default_conversion (op1);
3222 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3223 op2 = default_conversion (op2);
3224
3225 if (TREE_CODE (ifexp) == ERROR_MARK
3226 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3227 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3228 return error_mark_node;
3229
3230 type1 = TREE_TYPE (op1);
3231 code1 = TREE_CODE (type1);
3232 type2 = TREE_TYPE (op2);
3233 code2 = TREE_CODE (type2);
3234
3235 /* C90 does not permit non-lvalue arrays in conditional expressions.
3236 In C99 they will be pointers by now. */
3237 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
3238 {
3239 error ("non-lvalue array in conditional expression");
3240 return error_mark_node;
3241 }
3242
3243 /* Quickly detect the usual case where op1 and op2 have the same type
3244 after promotion. */
3245 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3246 {
3247 if (type1 == type2)
3248 result_type = type1;
3249 else
3250 result_type = TYPE_MAIN_VARIANT (type1);
3251 }
3252 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
3253 || code1 == COMPLEX_TYPE)
3254 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3255 || code2 == COMPLEX_TYPE))
3256 {
3257 result_type = c_common_type (type1, type2);
3258
3259 /* If -Wsign-compare, warn here if type1 and type2 have
3260 different signedness. We'll promote the signed to unsigned
3261 and later code won't know it used to be different.
3262 Do this check on the original types, so that explicit casts
3263 will be considered, but default promotions won't. */
3264 if (warn_sign_compare && !skip_evaluation)
3265 {
3266 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3267 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
3268
3269 if (unsigned_op1 ^ unsigned_op2)
3270 {
3271 bool ovf;
3272
3273 /* Do not warn if the result type is signed, since the
3274 signed type will only be chosen if it can represent
3275 all the values of the unsigned type. */
3276 if (!TYPE_UNSIGNED (result_type))
3277 /* OK */;
3278 /* Do not warn if the signed quantity is an unsuffixed
3279 integer literal (or some static constant expression
3280 involving such literals) and it is non-negative. */
3281 else if ((unsigned_op2
3282 && tree_expr_nonnegative_warnv_p (op1, &ovf))
3283 || (unsigned_op1
3284 && tree_expr_nonnegative_warnv_p (op2, &ovf)))
3285 /* OK */;
3286 else
3287 warning (0, "signed and unsigned type in conditional expression");
3288 }
3289 }
3290 }
3291 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3292 {
3293 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3294 pedwarn ("ISO C forbids conditional expr with only one void side");
3295 result_type = void_type_node;
3296 }
3297 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3298 {
3299 if (comp_target_types (type1, type2))
3300 result_type = common_pointer_type (type1, type2);
3301 else if (null_pointer_constant_p (orig_op1))
3302 result_type = qualify_type (type2, type1);
3303 else if (null_pointer_constant_p (orig_op2))
3304 result_type = qualify_type (type1, type2);
3305 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3306 {
3307 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == 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 (type1),
3311 TREE_TYPE (type2)));
3312 }
3313 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3314 {
3315 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3316 pedwarn ("ISO C forbids conditional expr between "
3317 "%<void *%> and function pointer");
3318 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
3319 TREE_TYPE (type1)));
3320 }
3321 else
3322 {
3323 pedwarn ("pointer type mismatch in conditional expression");
3324 result_type = build_pointer_type (void_type_node);
3325 }
3326 }
3327 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3328 {
3329 if (!null_pointer_constant_p (orig_op2))
3330 pedwarn ("pointer/integer type mismatch in conditional expression");
3331 else
3332 {
3333 op2 = null_pointer_node;
3334 }
3335 result_type = type1;
3336 }
3337 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3338 {
3339 if (!null_pointer_constant_p (orig_op1))
3340 pedwarn ("pointer/integer type mismatch in conditional expression");
3341 else
3342 {
3343 op1 = null_pointer_node;
3344 }
3345 result_type = type2;
3346 }
3347
3348 if (!result_type)
3349 {
3350 if (flag_cond_mismatch)
3351 result_type = void_type_node;
3352 else
3353 {
3354 error ("type mismatch in conditional expression");
3355 return error_mark_node;
3356 }
3357 }
3358
3359 /* Merge const and volatile flags of the incoming types. */
3360 result_type
3361 = build_type_variant (result_type,
3362 TREE_READONLY (op1) || TREE_READONLY (op2),
3363 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3364
3365 if (result_type != TREE_TYPE (op1))
3366 op1 = convert_and_check (result_type, op1);
3367 if (result_type != TREE_TYPE (op2))
3368 op2 = convert_and_check (result_type, op2);
3369
3370 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2);
3371 }
3372 \f
3373 /* Return a compound expression that performs two expressions and
3374 returns the value of the second of them. */
3375
3376 tree
3377 build_compound_expr (tree expr1, tree expr2)
3378 {
3379 if (!TREE_SIDE_EFFECTS (expr1))
3380 {
3381 /* The left-hand operand of a comma expression is like an expression
3382 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3383 any side-effects, unless it was explicitly cast to (void). */
3384 if (warn_unused_value)
3385 {
3386 if (VOID_TYPE_P (TREE_TYPE (expr1))
3387 && (TREE_CODE (expr1) == NOP_EXPR
3388 || TREE_CODE (expr1) == CONVERT_EXPR))
3389 ; /* (void) a, b */
3390 else if (VOID_TYPE_P (TREE_TYPE (expr1))
3391 && TREE_CODE (expr1) == COMPOUND_EXPR
3392 && (TREE_CODE (TREE_OPERAND (expr1, 1)) == CONVERT_EXPR
3393 || TREE_CODE (TREE_OPERAND (expr1, 1)) == NOP_EXPR))
3394 ; /* (void) a, (void) b, c */
3395 else
3396 warning (0, "left-hand operand of comma expression has no effect");
3397 }
3398 }
3399
3400 /* With -Wunused, we should also warn if the left-hand operand does have
3401 side-effects, but computes a value which is not used. For example, in
3402 `foo() + bar(), baz()' the result of the `+' operator is not used,
3403 so we should issue a warning. */
3404 else if (warn_unused_value)
3405 warn_if_unused_value (expr1, input_location);
3406
3407 if (expr2 == error_mark_node)
3408 return error_mark_node;
3409
3410 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
3411 }
3412
3413 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3414
3415 tree
3416 build_c_cast (tree type, tree expr)
3417 {
3418 tree value = expr;
3419
3420 if (type == error_mark_node || expr == error_mark_node)
3421 return error_mark_node;
3422
3423 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3424 only in <protocol> qualifications. But when constructing cast expressions,
3425 the protocols do matter and must be kept around. */
3426 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
3427 return build1 (NOP_EXPR, type, expr);
3428
3429 type = TYPE_MAIN_VARIANT (type);
3430
3431 if (TREE_CODE (type) == ARRAY_TYPE)
3432 {
3433 error ("cast specifies array type");
3434 return error_mark_node;
3435 }
3436
3437 if (TREE_CODE (type) == FUNCTION_TYPE)
3438 {
3439 error ("cast specifies function type");
3440 return error_mark_node;
3441 }
3442
3443 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3444 {
3445 if (pedantic)
3446 {
3447 if (TREE_CODE (type) == RECORD_TYPE
3448 || TREE_CODE (type) == UNION_TYPE)
3449 pedwarn ("ISO C forbids casting nonscalar to the same type");
3450 }
3451 }
3452 else if (TREE_CODE (type) == UNION_TYPE)
3453 {
3454 tree field;
3455
3456 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3457 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3458 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3459 break;
3460
3461 if (field)
3462 {
3463 tree t;
3464
3465 if (pedantic)
3466 pedwarn ("ISO C forbids casts to union type");
3467 t = digest_init (type,
3468 build_constructor_single (type, field, value),
3469 true, 0);
3470 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3471 TREE_INVARIANT (t) = TREE_INVARIANT (value);
3472 return t;
3473 }
3474 error ("cast to union type from type not present in union");
3475 return error_mark_node;
3476 }
3477 else
3478 {
3479 tree otype, ovalue;
3480
3481 if (type == void_type_node)
3482 return build1 (CONVERT_EXPR, type, value);
3483
3484 otype = TREE_TYPE (value);
3485
3486 /* Optionally warn about potentially worrisome casts. */
3487
3488 if (warn_cast_qual
3489 && TREE_CODE (type) == POINTER_TYPE
3490 && TREE_CODE (otype) == POINTER_TYPE)
3491 {
3492 tree in_type = type;
3493 tree in_otype = otype;
3494 int added = 0;
3495 int discarded = 0;
3496
3497 /* Check that the qualifiers on IN_TYPE are a superset of
3498 the qualifiers of IN_OTYPE. The outermost level of
3499 POINTER_TYPE nodes is uninteresting and we stop as soon
3500 as we hit a non-POINTER_TYPE node on either type. */
3501 do
3502 {
3503 in_otype = TREE_TYPE (in_otype);
3504 in_type = TREE_TYPE (in_type);
3505
3506 /* GNU C allows cv-qualified function types. 'const'
3507 means the function is very pure, 'volatile' means it
3508 can't return. We need to warn when such qualifiers
3509 are added, not when they're taken away. */
3510 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3511 && TREE_CODE (in_type) == FUNCTION_TYPE)
3512 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3513 else
3514 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3515 }
3516 while (TREE_CODE (in_type) == POINTER_TYPE
3517 && TREE_CODE (in_otype) == POINTER_TYPE);
3518
3519 if (added)
3520 warning (0, "cast adds new qualifiers to function type");
3521
3522 if (discarded)
3523 /* There are qualifiers present in IN_OTYPE that are not
3524 present in IN_TYPE. */
3525 warning (0, "cast discards qualifiers from pointer target type");
3526 }
3527
3528 /* Warn about possible alignment problems. */
3529 if (STRICT_ALIGNMENT
3530 && TREE_CODE (type) == POINTER_TYPE
3531 && TREE_CODE (otype) == POINTER_TYPE
3532 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3533 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3534 /* Don't warn about opaque types, where the actual alignment
3535 restriction is unknown. */
3536 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3537 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3538 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3539 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3540 warning (OPT_Wcast_align,
3541 "cast increases required alignment of target type");
3542
3543 if (TREE_CODE (type) == INTEGER_TYPE
3544 && TREE_CODE (otype) == POINTER_TYPE
3545 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
3546 /* Unlike conversion of integers to pointers, where the
3547 warning is disabled for converting constants because
3548 of cases such as SIG_*, warn about converting constant
3549 pointers to integers. In some cases it may cause unwanted
3550 sign extension, and a warning is appropriate. */
3551 warning (OPT_Wpointer_to_int_cast,
3552 "cast from pointer to integer of different size");
3553
3554 if (TREE_CODE (value) == CALL_EXPR
3555 && TREE_CODE (type) != TREE_CODE (otype))
3556 warning (OPT_Wbad_function_cast, "cast from function call of type %qT "
3557 "to non-matching type %qT", otype, type);
3558
3559 if (TREE_CODE (type) == POINTER_TYPE
3560 && TREE_CODE (otype) == INTEGER_TYPE
3561 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3562 /* Don't warn about converting any constant. */
3563 && !TREE_CONSTANT (value))
3564 warning (OPT_Wint_to_pointer_cast, "cast to pointer from integer "
3565 "of different size");
3566
3567 strict_aliasing_warning (otype, type, expr);
3568
3569 /* If pedantic, warn for conversions between function and object
3570 pointer types, except for converting a null pointer constant
3571 to function pointer type. */
3572 if (pedantic
3573 && TREE_CODE (type) == POINTER_TYPE
3574 && TREE_CODE (otype) == POINTER_TYPE
3575 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3576 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3577 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3578
3579 if (pedantic
3580 && TREE_CODE (type) == POINTER_TYPE
3581 && TREE_CODE (otype) == POINTER_TYPE
3582 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3583 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3584 && !null_pointer_constant_p (value))
3585 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3586
3587 ovalue = value;
3588 value = convert (type, value);
3589
3590 /* Ignore any integer overflow caused by the cast. */
3591 if (TREE_CODE (value) == INTEGER_CST)
3592 {
3593 if (CONSTANT_CLASS_P (ovalue) && TREE_OVERFLOW (ovalue))
3594 {
3595 if (!TREE_OVERFLOW (value))
3596 {
3597 /* Avoid clobbering a shared constant. */
3598 value = copy_node (value);
3599 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3600 }
3601 }
3602 else if (TREE_OVERFLOW (value))
3603 /* Reset VALUE's overflow flags, ensuring constant sharing. */
3604 value = build_int_cst_wide (TREE_TYPE (value),
3605 TREE_INT_CST_LOW (value),
3606 TREE_INT_CST_HIGH (value));
3607 }
3608 }
3609
3610 /* Don't let a cast be an lvalue. */
3611 if (value == expr)
3612 value = non_lvalue (value);
3613
3614 return value;
3615 }
3616
3617 /* Interpret a cast of expression EXPR to type TYPE. */
3618 tree
3619 c_cast_expr (struct c_type_name *type_name, tree expr)
3620 {
3621 tree type;
3622 int saved_wsp = warn_strict_prototypes;
3623
3624 /* This avoids warnings about unprototyped casts on
3625 integers. E.g. "#define SIG_DFL (void(*)())0". */
3626 if (TREE_CODE (expr) == INTEGER_CST)
3627 warn_strict_prototypes = 0;
3628 type = groktypename (type_name);
3629 warn_strict_prototypes = saved_wsp;
3630
3631 return build_c_cast (type, expr);
3632 }
3633 \f
3634 /* Build an assignment expression of lvalue LHS from value RHS.
3635 MODIFYCODE is the code for a binary operator that we use
3636 to combine the old value of LHS with RHS to get the new value.
3637 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3638
3639 tree
3640 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3641 {
3642 tree result;
3643 tree newrhs;
3644 tree lhstype = TREE_TYPE (lhs);
3645 tree olhstype = lhstype;
3646
3647 /* Types that aren't fully specified cannot be used in assignments. */
3648 lhs = require_complete_type (lhs);
3649
3650 /* Avoid duplicate error messages from operands that had errors. */
3651 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3652 return error_mark_node;
3653
3654 if (!lvalue_or_else (lhs, lv_assign))
3655 return error_mark_node;
3656
3657 STRIP_TYPE_NOPS (rhs);
3658
3659 newrhs = rhs;
3660
3661 /* If a binary op has been requested, combine the old LHS value with the RHS
3662 producing the value we should actually store into the LHS. */
3663
3664 if (modifycode != NOP_EXPR)
3665 {
3666 lhs = stabilize_reference (lhs);
3667 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3668 }
3669
3670 /* Give an error for storing in something that is 'const'. */
3671
3672 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3673 || ((TREE_CODE (lhstype) == RECORD_TYPE
3674 || TREE_CODE (lhstype) == UNION_TYPE)
3675 && C_TYPE_FIELDS_READONLY (lhstype)))
3676 {
3677 readonly_error (lhs, lv_assign);
3678 return error_mark_node;
3679 }
3680
3681 /* If storing into a structure or union member,
3682 it has probably been given type `int'.
3683 Compute the type that would go with
3684 the actual amount of storage the member occupies. */
3685
3686 if (TREE_CODE (lhs) == COMPONENT_REF
3687 && (TREE_CODE (lhstype) == INTEGER_TYPE
3688 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3689 || TREE_CODE (lhstype) == REAL_TYPE
3690 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3691 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3692
3693 /* If storing in a field that is in actuality a short or narrower than one,
3694 we must store in the field in its actual type. */
3695
3696 if (lhstype != TREE_TYPE (lhs))
3697 {
3698 lhs = copy_node (lhs);
3699 TREE_TYPE (lhs) = lhstype;
3700 }
3701
3702 /* Convert new value to destination type. */
3703
3704 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign,
3705 NULL_TREE, NULL_TREE, 0);
3706 if (TREE_CODE (newrhs) == ERROR_MARK)
3707 return error_mark_node;
3708
3709 /* Emit ObjC write barrier, if necessary. */
3710 if (c_dialect_objc () && flag_objc_gc)
3711 {
3712 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
3713 if (result)
3714 return result;
3715 }
3716
3717 /* Scan operands. */
3718
3719 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
3720 TREE_SIDE_EFFECTS (result) = 1;
3721
3722 /* If we got the LHS in a different type for storing in,
3723 convert the result back to the nominal type of LHS
3724 so that the value we return always has the same type
3725 as the LHS argument. */
3726
3727 if (olhstype == TREE_TYPE (result))
3728 return result;
3729 return convert_for_assignment (olhstype, result, ic_assign,
3730 NULL_TREE, NULL_TREE, 0);
3731 }
3732 \f
3733 /* Convert value RHS to type TYPE as preparation for an assignment
3734 to an lvalue of type TYPE.
3735 The real work of conversion is done by `convert'.
3736 The purpose of this function is to generate error messages
3737 for assignments that are not allowed in C.
3738 ERRTYPE says whether it is argument passing, assignment,
3739 initialization or return.
3740
3741 FUNCTION is a tree for the function being called.
3742 PARMNUM is the number of the argument, for printing in error messages. */
3743
3744 static tree
3745 convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
3746 tree fundecl, tree function, int parmnum)
3747 {
3748 enum tree_code codel = TREE_CODE (type);
3749 tree rhstype;
3750 enum tree_code coder;
3751 tree rname = NULL_TREE;
3752 bool objc_ok = false;
3753
3754 if (errtype == ic_argpass || errtype == ic_argpass_nonproto)
3755 {
3756 tree selector;
3757 /* Change pointer to function to the function itself for
3758 diagnostics. */
3759 if (TREE_CODE (function) == ADDR_EXPR
3760 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
3761 function = TREE_OPERAND (function, 0);
3762
3763 /* Handle an ObjC selector specially for diagnostics. */
3764 selector = objc_message_selector ();
3765 rname = function;
3766 if (selector && parmnum > 2)
3767 {
3768 rname = selector;
3769 parmnum -= 2;
3770 }
3771 }
3772
3773 /* This macro is used to emit diagnostics to ensure that all format
3774 strings are complete sentences, visible to gettext and checked at
3775 compile time. */
3776 #define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \
3777 do { \
3778 switch (errtype) \
3779 { \
3780 case ic_argpass: \
3781 pedwarn (AR, parmnum, rname); \
3782 break; \
3783 case ic_argpass_nonproto: \
3784 warning (0, AR, parmnum, rname); \
3785 break; \
3786 case ic_assign: \
3787 pedwarn (AS); \
3788 break; \
3789 case ic_init: \
3790 pedwarn (IN); \
3791 break; \
3792 case ic_return: \
3793 pedwarn (RE); \
3794 break; \
3795 default: \
3796 gcc_unreachable (); \
3797 } \
3798 } while (0)
3799
3800 STRIP_TYPE_NOPS (rhs);
3801
3802 if (optimize && TREE_CODE (rhs) == VAR_DECL
3803 && TREE_CODE (TREE_TYPE (rhs)) != ARRAY_TYPE)
3804 rhs = decl_constant_value_for_broken_optimization (rhs);
3805
3806 rhstype = TREE_TYPE (rhs);
3807 coder = TREE_CODE (rhstype);
3808
3809 if (coder == ERROR_MARK)
3810 return error_mark_node;
3811
3812 if (c_dialect_objc ())
3813 {
3814 int parmno;
3815
3816 switch (errtype)
3817 {
3818 case ic_return:
3819 parmno = 0;
3820 break;
3821
3822 case ic_assign:
3823 parmno = -1;
3824 break;
3825
3826 case ic_init:
3827 parmno = -2;
3828 break;
3829
3830 default:
3831 parmno = parmnum;
3832 break;
3833 }
3834
3835 objc_ok = objc_compare_types (type, rhstype, parmno, rname);
3836 }
3837
3838 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3839 return rhs;
3840
3841 if (coder == VOID_TYPE)
3842 {
3843 /* Except for passing an argument to an unprototyped function,
3844 this is a constraint violation. When passing an argument to
3845 an unprototyped function, it is compile-time undefined;
3846 making it a constraint in that case was rejected in
3847 DR#252. */
3848 error ("void value not ignored as it ought to be");
3849 return error_mark_node;
3850 }
3851 /* A type converts to a reference to it.
3852 This code doesn't fully support references, it's just for the
3853 special case of va_start and va_copy. */
3854 if (codel == REFERENCE_TYPE
3855 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
3856 {
3857 if (!lvalue_p (rhs))
3858 {
3859 error ("cannot pass rvalue to reference parameter");
3860 return error_mark_node;
3861 }
3862 if (!c_mark_addressable (rhs))
3863 return error_mark_node;
3864 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
3865
3866 /* We already know that these two types are compatible, but they
3867 may not be exactly identical. In fact, `TREE_TYPE (type)' is
3868 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
3869 likely to be va_list, a typedef to __builtin_va_list, which
3870 is different enough that it will cause problems later. */
3871 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
3872 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
3873
3874 rhs = build1 (NOP_EXPR, type, rhs);
3875 return rhs;
3876 }
3877 /* Some types can interconvert without explicit casts. */
3878 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
3879 && vector_types_convertible_p (type, TREE_TYPE (rhs), true))
3880 return convert (type, rhs);
3881 /* Arithmetic types all interconvert, and enum is treated like int. */
3882 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
3883 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
3884 || codel == BOOLEAN_TYPE)
3885 && (coder == INTEGER_TYPE || coder == REAL_TYPE
3886 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
3887 || coder == BOOLEAN_TYPE))
3888 return convert_and_check (type, rhs);
3889
3890 /* Conversion to a transparent union from its member types.
3891 This applies only to function arguments. */
3892 else if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type)
3893 && (errtype == ic_argpass || errtype == ic_argpass_nonproto))
3894 {
3895 tree memb, marginal_memb = NULL_TREE;
3896
3897 for (memb = TYPE_FIELDS (type); memb ; memb = TREE_CHAIN (memb))
3898 {
3899 tree memb_type = TREE_TYPE (memb);
3900
3901 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
3902 TYPE_MAIN_VARIANT (rhstype)))
3903 break;
3904
3905 if (TREE_CODE (memb_type) != POINTER_TYPE)
3906 continue;
3907
3908 if (coder == POINTER_TYPE)
3909 {
3910 tree ttl = TREE_TYPE (memb_type);
3911 tree ttr = TREE_TYPE (rhstype);
3912
3913 /* Any non-function converts to a [const][volatile] void *
3914 and vice versa; otherwise, targets must be the same.
3915 Meanwhile, the lhs target must have all the qualifiers of
3916 the rhs. */
3917 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3918 || comp_target_types (memb_type, rhstype))
3919 {
3920 /* If this type won't generate any warnings, use it. */
3921 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
3922 || ((TREE_CODE (ttr) == FUNCTION_TYPE
3923 && TREE_CODE (ttl) == FUNCTION_TYPE)
3924 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3925 == TYPE_QUALS (ttr))
3926 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3927 == TYPE_QUALS (ttl))))
3928 break;
3929
3930 /* Keep looking for a better type, but remember this one. */
3931 if (!marginal_memb)
3932 marginal_memb = memb;
3933 }
3934 }
3935
3936 /* Can convert integer zero to any pointer type. */
3937 if (null_pointer_constant_p (rhs))
3938 {
3939 rhs = null_pointer_node;
3940 break;
3941 }
3942 }
3943
3944 if (memb || marginal_memb)
3945 {
3946 if (!memb)
3947 {
3948 /* We have only a marginally acceptable member type;
3949 it needs a warning. */
3950 tree ttl = TREE_TYPE (TREE_TYPE (marginal_memb));
3951 tree ttr = TREE_TYPE (rhstype);
3952
3953 /* Const and volatile mean something different for function
3954 types, so the usual warnings are not appropriate. */
3955 if (TREE_CODE (ttr) == FUNCTION_TYPE
3956 && TREE_CODE (ttl) == FUNCTION_TYPE)
3957 {
3958 /* Because const and volatile on functions are
3959 restrictions that say the function will not do
3960 certain things, it is okay to use a const or volatile
3961 function where an ordinary one is wanted, but not
3962 vice-versa. */
3963 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3964 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE "
3965 "makes qualified function "
3966 "pointer from unqualified"),
3967 G_("assignment makes qualified "
3968 "function pointer from "
3969 "unqualified"),
3970 G_("initialization makes qualified "
3971 "function pointer from "
3972 "unqualified"),
3973 G_("return makes qualified function "
3974 "pointer from unqualified"));
3975 }
3976 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
3977 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
3978 "qualifiers from pointer target type"),
3979 G_("assignment discards qualifiers "
3980 "from pointer target type"),
3981 G_("initialization discards qualifiers "
3982 "from pointer target type"),
3983 G_("return discards qualifiers from "
3984 "pointer target type"));
3985
3986 memb = marginal_memb;
3987 }
3988
3989 if (pedantic && (!fundecl || !DECL_IN_SYSTEM_HEADER (fundecl)))
3990 pedwarn ("ISO C prohibits argument conversion to union type");
3991
3992 return build_constructor_single (type, memb, rhs);
3993 }
3994 }
3995
3996 /* Conversions among pointers */
3997 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
3998 && (coder == codel))
3999 {
4000 tree ttl = TREE_TYPE (type);
4001 tree ttr = TREE_TYPE (rhstype);
4002 tree mvl = ttl;
4003 tree mvr = ttr;
4004 bool is_opaque_pointer;
4005 int target_cmp = 0; /* Cache comp_target_types () result. */
4006
4007 if (TREE_CODE (mvl) != ARRAY_TYPE)
4008 mvl = TYPE_MAIN_VARIANT (mvl);
4009 if (TREE_CODE (mvr) != ARRAY_TYPE)
4010 mvr = TYPE_MAIN_VARIANT (mvr);
4011 /* Opaque pointers are treated like void pointers. */
4012 is_opaque_pointer = (targetm.vector_opaque_p (type)
4013 || targetm.vector_opaque_p (rhstype))
4014 && TREE_CODE (ttl) == VECTOR_TYPE
4015 && TREE_CODE (ttr) == VECTOR_TYPE;
4016
4017 /* C++ does not allow the implicit conversion void* -> T*. However,
4018 for the purpose of reducing the number of false positives, we
4019 tolerate the special case of
4020
4021 int *p = NULL;
4022
4023 where NULL is typically defined in C to be '(void *) 0'. */
4024 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl))
4025 warning (OPT_Wc___compat, "request for implicit conversion from "
4026 "%qT to %qT not permitted in C++", rhstype, type);
4027
4028 /* Check if the right-hand side has a format attribute but the
4029 left-hand side doesn't. */
4030 if (warn_missing_format_attribute
4031 && check_missing_format_attribute (type, rhstype))
4032 {
4033 switch (errtype)
4034 {
4035 case ic_argpass:
4036 case ic_argpass_nonproto:
4037 warning (OPT_Wmissing_format_attribute,
4038 "argument %d of %qE might be "
4039 "a candidate for a format attribute",
4040 parmnum, rname);
4041 break;
4042 case ic_assign:
4043 warning (OPT_Wmissing_format_attribute,
4044 "assignment left-hand side might be "
4045 "a candidate for a format attribute");
4046 break;
4047 case ic_init:
4048 warning (OPT_Wmissing_format_attribute,
4049 "initialization left-hand side might be "
4050 "a candidate for a format attribute");
4051 break;
4052 case ic_return:
4053 warning (OPT_Wmissing_format_attribute,
4054 "return type might be "
4055 "a candidate for a format attribute");
4056 break;
4057 default:
4058 gcc_unreachable ();
4059 }
4060 }
4061
4062 /* Any non-function converts to a [const][volatile] void *
4063 and vice versa; otherwise, targets must be the same.
4064 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4065 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4066 || (target_cmp = comp_target_types (type, rhstype))
4067 || is_opaque_pointer
4068 || (c_common_unsigned_type (mvl)
4069 == c_common_unsigned_type (mvr)))
4070 {
4071 if (pedantic
4072 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
4073 ||
4074 (VOID_TYPE_P (ttr)
4075 && !null_pointer_constant_p (rhs)
4076 && TREE_CODE (ttl) == FUNCTION_TYPE)))
4077 WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of "
4078 "%qE between function pointer "
4079 "and %<void *%>"),
4080 G_("ISO C forbids assignment between "
4081 "function pointer and %<void *%>"),
4082 G_("ISO C forbids initialization between "
4083 "function pointer and %<void *%>"),
4084 G_("ISO C forbids return between function "
4085 "pointer and %<void *%>"));
4086 /* Const and volatile mean something different for function types,
4087 so the usual warnings are not appropriate. */
4088 else if (TREE_CODE (ttr) != FUNCTION_TYPE
4089 && TREE_CODE (ttl) != FUNCTION_TYPE)
4090 {
4091 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4092 {
4093 /* Types differing only by the presence of the 'volatile'
4094 qualifier are acceptable if the 'volatile' has been added
4095 in by the Objective-C EH machinery. */
4096 if (!objc_type_quals_match (ttl, ttr))
4097 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
4098 "qualifiers from pointer target type"),
4099 G_("assignment discards qualifiers "
4100 "from pointer target type"),
4101 G_("initialization discards qualifiers "
4102 "from pointer target type"),
4103 G_("return discards qualifiers from "
4104 "pointer target type"));
4105 }
4106 /* If this is not a case of ignoring a mismatch in signedness,
4107 no warning. */
4108 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4109 || target_cmp)
4110 ;
4111 /* If there is a mismatch, do warn. */
4112 else if (warn_pointer_sign)
4113 WARN_FOR_ASSIGNMENT (G_("pointer targets in passing argument "
4114 "%d of %qE differ in signedness"),
4115 G_("pointer targets in assignment "
4116 "differ in signedness"),
4117 G_("pointer targets in initialization "
4118 "differ in signedness"),
4119 G_("pointer targets in return differ "
4120 "in signedness"));
4121 }
4122 else if (TREE_CODE (ttl) == FUNCTION_TYPE
4123 && TREE_CODE (ttr) == FUNCTION_TYPE)
4124 {
4125 /* Because const and volatile on functions are restrictions
4126 that say the function will not do certain things,
4127 it is okay to use a const or volatile function
4128 where an ordinary one is wanted, but not vice-versa. */
4129 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4130 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
4131 "qualified function pointer "
4132 "from unqualified"),
4133 G_("assignment makes qualified function "
4134 "pointer from unqualified"),
4135 G_("initialization makes qualified "
4136 "function pointer from unqualified"),
4137 G_("return makes qualified function "
4138 "pointer from unqualified"));
4139 }
4140 }
4141 else
4142 /* Avoid warning about the volatile ObjC EH puts on decls. */
4143 if (!objc_ok)
4144 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE from "
4145 "incompatible pointer type"),
4146 G_("assignment from incompatible pointer type"),
4147 G_("initialization from incompatible "
4148 "pointer type"),
4149 G_("return from incompatible pointer type"));
4150
4151 return convert (type, rhs);
4152 }
4153 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
4154 {
4155 /* ??? This should not be an error when inlining calls to
4156 unprototyped functions. */
4157 error ("invalid use of non-lvalue array");
4158 return error_mark_node;
4159 }
4160 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
4161 {
4162 /* An explicit constant 0 can convert to a pointer,
4163 or one that results from arithmetic, even including
4164 a cast to integer type. */
4165 if (!null_pointer_constant_p (rhs))
4166 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
4167 "pointer from integer without a cast"),
4168 G_("assignment makes pointer from integer "
4169 "without a cast"),
4170 G_("initialization makes pointer from "
4171 "integer without a cast"),
4172 G_("return makes pointer from integer "
4173 "without a cast"));
4174
4175 return convert (type, rhs);
4176 }
4177 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
4178 {
4179 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes integer "
4180 "from pointer without a cast"),
4181 G_("assignment makes integer from pointer "
4182 "without a cast"),
4183 G_("initialization makes integer from pointer "
4184 "without a cast"),
4185 G_("return makes integer from pointer "
4186 "without a cast"));
4187 return convert (type, rhs);
4188 }
4189 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
4190 return convert (type, rhs);
4191
4192 switch (errtype)
4193 {
4194 case ic_argpass:
4195 case ic_argpass_nonproto:
4196 /* ??? This should not be an error when inlining calls to
4197 unprototyped functions. */
4198 error ("incompatible type for argument %d of %qE", parmnum, rname);
4199 break;
4200 case ic_assign:
4201 error ("incompatible types in assignment");
4202 break;
4203 case ic_init:
4204 error ("incompatible types in initialization");
4205 break;
4206 case ic_return:
4207 error ("incompatible types in return");
4208 break;
4209 default:
4210 gcc_unreachable ();
4211 }
4212
4213 return error_mark_node;
4214 }
4215
4216 /* Convert VALUE for assignment into inlined parameter PARM. ARGNUM
4217 is used for error and warning reporting and indicates which argument
4218 is being processed. */
4219
4220 tree
4221 c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum)
4222 {
4223 tree ret, type;
4224
4225 /* If FN was prototyped at the call site, the value has been converted
4226 already in convert_arguments.
4227 However, we might see a prototype now that was not in place when
4228 the function call was seen, so check that the VALUE actually matches
4229 PARM before taking an early exit. */
4230 if (!value
4231 || (TYPE_ARG_TYPES (TREE_TYPE (fn))
4232 && (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
4233 == TYPE_MAIN_VARIANT (TREE_TYPE (value)))))
4234 return value;
4235
4236 type = TREE_TYPE (parm);
4237 ret = convert_for_assignment (type, value,
4238 ic_argpass_nonproto, fn,
4239 fn, argnum);
4240 if (targetm.calls.promote_prototypes (TREE_TYPE (fn))
4241 && INTEGRAL_TYPE_P (type)
4242 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
4243 ret = default_conversion (ret);
4244 return ret;
4245 }
4246 \f
4247 /* If VALUE is a compound expr all of whose expressions are constant, then
4248 return its value. Otherwise, return error_mark_node.
4249
4250 This is for handling COMPOUND_EXPRs as initializer elements
4251 which is allowed with a warning when -pedantic is specified. */
4252
4253 static tree
4254 valid_compound_expr_initializer (tree value, tree endtype)
4255 {
4256 if (TREE_CODE (value) == COMPOUND_EXPR)
4257 {
4258 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4259 == error_mark_node)
4260 return error_mark_node;
4261 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4262 endtype);
4263 }
4264 else if (!initializer_constant_valid_p (value, endtype))
4265 return error_mark_node;
4266 else
4267 return value;
4268 }
4269 \f
4270 /* Perform appropriate conversions on the initial value of a variable,
4271 store it in the declaration DECL,
4272 and print any error messages that are appropriate.
4273 If the init is invalid, store an ERROR_MARK. */
4274
4275 void
4276 store_init_value (tree decl, tree init)
4277 {
4278 tree value, type;
4279
4280 /* If variable's type was invalidly declared, just ignore it. */
4281
4282 type = TREE_TYPE (decl);
4283 if (TREE_CODE (type) == ERROR_MARK)
4284 return;
4285
4286 /* Digest the specified initializer into an expression. */
4287
4288 value = digest_init (type, init, true, TREE_STATIC (decl));
4289
4290 /* Store the expression if valid; else report error. */
4291
4292 if (!in_system_header
4293 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
4294 warning (OPT_Wtraditional, "traditional C rejects automatic "
4295 "aggregate initialization");
4296
4297 DECL_INITIAL (decl) = value;
4298
4299 /* ANSI wants warnings about out-of-range constant initializers. */
4300 STRIP_TYPE_NOPS (value);
4301 if (TREE_STATIC (decl))
4302 constant_expression_warning (value);
4303
4304 /* Check if we need to set array size from compound literal size. */
4305 if (TREE_CODE (type) == ARRAY_TYPE
4306 && TYPE_DOMAIN (type) == 0
4307 && value != error_mark_node)
4308 {
4309 tree inside_init = init;
4310
4311 STRIP_TYPE_NOPS (inside_init);
4312 inside_init = fold (inside_init);
4313
4314 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4315 {
4316 tree cldecl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4317
4318 if (TYPE_DOMAIN (TREE_TYPE (cldecl)))
4319 {
4320 /* For int foo[] = (int [3]){1}; we need to set array size
4321 now since later on array initializer will be just the
4322 brace enclosed list of the compound literal. */
4323 type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
4324 TREE_TYPE (decl) = type;
4325 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (cldecl));
4326 layout_type (type);
4327 layout_decl (cldecl, 0);
4328 }
4329 }
4330 }
4331 }
4332 \f
4333 /* Methods for storing and printing names for error messages. */
4334
4335 /* Implement a spelling stack that allows components of a name to be pushed
4336 and popped. Each element on the stack is this structure. */
4337
4338 struct spelling
4339 {
4340 int kind;
4341 union
4342 {
4343 unsigned HOST_WIDE_INT i;
4344 const char *s;
4345 } u;
4346 };
4347
4348 #define SPELLING_STRING 1
4349 #define SPELLING_MEMBER 2
4350 #define SPELLING_BOUNDS 3
4351
4352 static struct spelling *spelling; /* Next stack element (unused). */
4353 static struct spelling *spelling_base; /* Spelling stack base. */
4354 static int spelling_size; /* Size of the spelling stack. */
4355
4356 /* Macros to save and restore the spelling stack around push_... functions.
4357 Alternative to SAVE_SPELLING_STACK. */
4358
4359 #define SPELLING_DEPTH() (spelling - spelling_base)
4360 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4361
4362 /* Push an element on the spelling stack with type KIND and assign VALUE
4363 to MEMBER. */
4364
4365 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4366 { \
4367 int depth = SPELLING_DEPTH (); \
4368 \
4369 if (depth >= spelling_size) \
4370 { \
4371 spelling_size += 10; \
4372 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
4373 spelling_size); \
4374 RESTORE_SPELLING_DEPTH (depth); \
4375 } \
4376 \
4377 spelling->kind = (KIND); \
4378 spelling->MEMBER = (VALUE); \
4379 spelling++; \
4380 }
4381
4382 /* Push STRING on the stack. Printed literally. */
4383
4384 static void
4385 push_string (const char *string)
4386 {
4387 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4388 }
4389
4390 /* Push a member name on the stack. Printed as '.' STRING. */
4391
4392 static void
4393 push_member_name (tree decl)
4394 {
4395 const char *const string
4396 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4397 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4398 }
4399
4400 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4401
4402 static void
4403 push_array_bounds (unsigned HOST_WIDE_INT bounds)
4404 {
4405 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4406 }
4407
4408 /* Compute the maximum size in bytes of the printed spelling. */
4409
4410 static int
4411 spelling_length (void)
4412 {
4413 int size = 0;
4414 struct spelling *p;
4415
4416 for (p = spelling_base; p < spelling; p++)
4417 {
4418 if (p->kind == SPELLING_BOUNDS)
4419 size += 25;
4420 else
4421 size += strlen (p->u.s) + 1;
4422 }
4423
4424 return size;
4425 }
4426
4427 /* Print the spelling to BUFFER and return it. */
4428
4429 static char *
4430 print_spelling (char *buffer)
4431 {
4432 char *d = buffer;
4433 struct spelling *p;
4434
4435 for (p = spelling_base; p < spelling; p++)
4436 if (p->kind == SPELLING_BOUNDS)
4437 {
4438 sprintf (d, "[" HOST_WIDE_INT_PRINT_UNSIGNED "]", p->u.i);
4439 d += strlen (d);
4440 }
4441 else
4442 {
4443 const char *s;
4444 if (p->kind == SPELLING_MEMBER)
4445 *d++ = '.';
4446 for (s = p->u.s; (*d = *s++); d++)
4447 ;
4448 }
4449 *d++ = '\0';
4450 return buffer;
4451 }
4452
4453 /* Issue an error message for a bad initializer component.
4454 MSGID identifies the message.
4455 The component name is taken from the spelling stack. */
4456
4457 void
4458 error_init (const char *msgid)
4459 {
4460 char *ofwhat;
4461
4462 error ("%s", _(msgid));
4463 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4464 if (*ofwhat)
4465 error ("(near initialization for %qs)", ofwhat);
4466 }
4467
4468 /* Issue a pedantic warning for a bad initializer component.
4469 MSGID identifies the message.
4470 The component name is taken from the spelling stack. */
4471
4472 void
4473 pedwarn_init (const char *msgid)
4474 {
4475 char *ofwhat;
4476
4477 pedwarn ("%s", _(msgid));
4478 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4479 if (*ofwhat)
4480 pedwarn ("(near initialization for %qs)", ofwhat);
4481 }
4482
4483 /* Issue a warning for a bad initializer component.
4484 MSGID identifies the message.
4485 The component name is taken from the spelling stack. */
4486
4487 static void
4488 warning_init (const char *msgid)
4489 {
4490 char *ofwhat;
4491
4492 warning (0, "%s", _(msgid));
4493 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4494 if (*ofwhat)
4495 warning (0, "(near initialization for %qs)", ofwhat);
4496 }
4497 \f
4498 /* If TYPE is an array type and EXPR is a parenthesized string
4499 constant, warn if pedantic that EXPR is being used to initialize an
4500 object of type TYPE. */
4501
4502 void
4503 maybe_warn_string_init (tree type, struct c_expr expr)
4504 {
4505 if (pedantic
4506 && TREE_CODE (type) == ARRAY_TYPE
4507 && TREE_CODE (expr.value) == STRING_CST
4508 && expr.original_code != STRING_CST)
4509 pedwarn_init ("array initialized from parenthesized string constant");
4510 }
4511
4512 /* Digest the parser output INIT as an initializer for type TYPE.
4513 Return a C expression of type TYPE to represent the initial value.
4514
4515 If INIT is a string constant, STRICT_STRING is true if it is
4516 unparenthesized or we should not warn here for it being parenthesized.
4517 For other types of INIT, STRICT_STRING is not used.
4518
4519 REQUIRE_CONSTANT requests an error if non-constant initializers or
4520 elements are seen. */
4521
4522 static tree
4523 digest_init (tree type, tree init, bool strict_string, int require_constant)
4524 {
4525 enum tree_code code = TREE_CODE (type);
4526 tree inside_init = init;
4527
4528 if (type == error_mark_node
4529 || !init
4530 || init == error_mark_node
4531 || TREE_TYPE (init) == error_mark_node)
4532 return error_mark_node;
4533
4534 STRIP_TYPE_NOPS (inside_init);
4535
4536 inside_init = fold (inside_init);
4537
4538 /* Initialization of an array of chars from a string constant
4539 optionally enclosed in braces. */
4540
4541 if (code == ARRAY_TYPE && inside_init
4542 && TREE_CODE (inside_init) == STRING_CST)
4543 {
4544 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4545 /* Note that an array could be both an array of character type
4546 and an array of wchar_t if wchar_t is signed char or unsigned
4547 char. */
4548 bool char_array = (typ1 == char_type_node
4549 || typ1 == signed_char_type_node
4550 || typ1 == unsigned_char_type_node);
4551 bool wchar_array = !!comptypes (typ1, wchar_type_node);
4552 if (char_array || wchar_array)
4553 {
4554 struct c_expr expr;
4555 bool char_string;
4556 expr.value = inside_init;
4557 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
4558 maybe_warn_string_init (type, expr);
4559
4560 char_string
4561 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4562 == char_type_node);
4563
4564 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4565 TYPE_MAIN_VARIANT (type)))
4566 return inside_init;
4567
4568 if (!wchar_array && !char_string)
4569 {
4570 error_init ("char-array initialized from wide string");
4571 return error_mark_node;
4572 }
4573 if (char_string && !char_array)
4574 {
4575 error_init ("wchar_t-array initialized from non-wide string");
4576 return error_mark_node;
4577 }
4578
4579 TREE_TYPE (inside_init) = type;
4580 if (TYPE_DOMAIN (type) != 0
4581 && TYPE_SIZE (type) != 0
4582 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4583 /* Subtract 1 (or sizeof (wchar_t))
4584 because it's ok to ignore the terminating null char
4585 that is counted in the length of the constant. */
4586 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4587 TREE_STRING_LENGTH (inside_init)
4588 - ((TYPE_PRECISION (typ1)
4589 != TYPE_PRECISION (char_type_node))
4590 ? (TYPE_PRECISION (wchar_type_node)
4591 / BITS_PER_UNIT)
4592 : 1)))
4593 pedwarn_init ("initializer-string for array of chars is too long");
4594
4595 return inside_init;
4596 }
4597 else if (INTEGRAL_TYPE_P (typ1))
4598 {
4599 error_init ("array of inappropriate type initialized "
4600 "from string constant");
4601 return error_mark_node;
4602 }
4603 }
4604
4605 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4606 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4607 below and handle as a constructor. */
4608 if (code == VECTOR_TYPE
4609 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
4610 && vector_types_convertible_p (TREE_TYPE (inside_init), type, true)
4611 && TREE_CONSTANT (inside_init))
4612 {
4613 if (TREE_CODE (inside_init) == VECTOR_CST
4614 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4615 TYPE_MAIN_VARIANT (type)))
4616 return inside_init;
4617
4618 if (TREE_CODE (inside_init) == CONSTRUCTOR)
4619 {
4620 unsigned HOST_WIDE_INT ix;
4621 tree value;
4622 bool constant_p = true;
4623
4624 /* Iterate through elements and check if all constructor
4625 elements are *_CSTs. */
4626 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (inside_init), ix, value)
4627 if (!CONSTANT_CLASS_P (value))
4628 {
4629 constant_p = false;
4630 break;
4631 }
4632
4633 if (constant_p)
4634 return build_vector_from_ctor (type,
4635 CONSTRUCTOR_ELTS (inside_init));
4636 }
4637 }
4638
4639 /* Any type can be initialized
4640 from an expression of the same type, optionally with braces. */
4641
4642 if (inside_init && TREE_TYPE (inside_init) != 0
4643 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4644 TYPE_MAIN_VARIANT (type))
4645 || (code == ARRAY_TYPE
4646 && comptypes (TREE_TYPE (inside_init), type))
4647 || (code == VECTOR_TYPE
4648 && comptypes (TREE_TYPE (inside_init), type))
4649 || (code == POINTER_TYPE
4650 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4651 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4652 TREE_TYPE (type)))))
4653 {
4654 if (code == POINTER_TYPE)
4655 {
4656 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4657 {
4658 if (TREE_CODE (inside_init) == STRING_CST
4659 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4660 inside_init = array_to_pointer_conversion (inside_init);
4661 else
4662 {
4663 error_init ("invalid use of non-lvalue array");
4664 return error_mark_node;
4665 }
4666 }
4667 }
4668
4669 if (code == VECTOR_TYPE)
4670 /* Although the types are compatible, we may require a
4671 conversion. */
4672 inside_init = convert (type, inside_init);
4673
4674 if (require_constant
4675 && (code == VECTOR_TYPE || !flag_isoc99)
4676 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4677 {
4678 /* As an extension, allow initializing objects with static storage
4679 duration with compound literals (which are then treated just as
4680 the brace enclosed list they contain). Also allow this for
4681 vectors, as we can only assign them with compound literals. */
4682 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4683 inside_init = DECL_INITIAL (decl);
4684 }
4685
4686 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4687 && TREE_CODE (inside_init) != CONSTRUCTOR)
4688 {
4689 error_init ("array initialized from non-constant array expression");
4690 return error_mark_node;
4691 }
4692
4693 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4694 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4695
4696 /* Compound expressions can only occur here if -pedantic or
4697 -pedantic-errors is specified. In the later case, we always want
4698 an error. In the former case, we simply want a warning. */
4699 if (require_constant && pedantic
4700 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4701 {
4702 inside_init
4703 = valid_compound_expr_initializer (inside_init,
4704 TREE_TYPE (inside_init));
4705 if (inside_init == error_mark_node)
4706 error_init ("initializer element is not constant");
4707 else
4708 pedwarn_init ("initializer element is not constant");
4709 if (flag_pedantic_errors)
4710 inside_init = error_mark_node;
4711 }
4712 else if (require_constant
4713 && !initializer_constant_valid_p (inside_init,
4714 TREE_TYPE (inside_init)))
4715 {
4716 error_init ("initializer element is not constant");
4717 inside_init = error_mark_node;
4718 }
4719
4720 /* Added to enable additional -Wmissing-format-attribute warnings. */
4721 if (TREE_CODE (TREE_TYPE (inside_init)) == POINTER_TYPE)
4722 inside_init = convert_for_assignment (type, inside_init, ic_init, NULL_TREE,
4723 NULL_TREE, 0);
4724 return inside_init;
4725 }
4726
4727 /* Handle scalar types, including conversions. */
4728
4729 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4730 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
4731 || code == VECTOR_TYPE)
4732 {
4733 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE
4734 && (TREE_CODE (init) == STRING_CST
4735 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR))
4736 init = array_to_pointer_conversion (init);
4737 inside_init
4738 = convert_for_assignment (type, init, ic_init,
4739 NULL_TREE, NULL_TREE, 0);
4740
4741 /* Check to see if we have already given an error message. */
4742 if (inside_init == error_mark_node)
4743 ;
4744 else if (require_constant && !TREE_CONSTANT (inside_init))
4745 {
4746 error_init ("initializer element is not constant");
4747 inside_init = error_mark_node;
4748 }
4749 else if (require_constant
4750 && !initializer_constant_valid_p (inside_init,
4751 TREE_TYPE (inside_init)))
4752 {
4753 error_init ("initializer element is not computable at load time");
4754 inside_init = error_mark_node;
4755 }
4756
4757 return inside_init;
4758 }
4759
4760 /* Come here only for records and arrays. */
4761
4762 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4763 {
4764 error_init ("variable-sized object may not be initialized");
4765 return error_mark_node;
4766 }
4767
4768 error_init ("invalid initializer");
4769 return error_mark_node;
4770 }
4771 \f
4772 /* Handle initializers that use braces. */
4773
4774 /* Type of object we are accumulating a constructor for.
4775 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4776 static tree constructor_type;
4777
4778 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4779 left to fill. */
4780 static tree constructor_fields;
4781
4782 /* For an ARRAY_TYPE, this is the specified index
4783 at which to store the next element we get. */
4784 static tree constructor_index;
4785
4786 /* For an ARRAY_TYPE, this is the maximum index. */
4787 static tree constructor_max_index;
4788
4789 /* For a RECORD_TYPE, this is the first field not yet written out. */
4790 static tree constructor_unfilled_fields;
4791
4792 /* For an ARRAY_TYPE, this is the index of the first element
4793 not yet written out. */
4794 static tree constructor_unfilled_index;
4795
4796 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4797 This is so we can generate gaps between fields, when appropriate. */
4798 static tree constructor_bit_index;
4799
4800 /* If we are saving up the elements rather than allocating them,
4801 this is the list of elements so far (in reverse order,
4802 most recent first). */
4803 static VEC(constructor_elt,gc) *constructor_elements;
4804
4805 /* 1 if constructor should be incrementally stored into a constructor chain,
4806 0 if all the elements should be kept in AVL tree. */
4807 static int constructor_incremental;
4808
4809 /* 1 if so far this constructor's elements are all compile-time constants. */
4810 static int constructor_constant;
4811
4812 /* 1 if so far this constructor's elements are all valid address constants. */
4813 static int constructor_simple;
4814
4815 /* 1 if this constructor is erroneous so far. */
4816 static int constructor_erroneous;
4817
4818 /* Structure for managing pending initializer elements, organized as an
4819 AVL tree. */
4820
4821 struct init_node
4822 {
4823 struct init_node *left, *right;
4824 struct init_node *parent;
4825 int balance;
4826 tree purpose;
4827 tree value;
4828 };
4829
4830 /* Tree of pending elements at this constructor level.
4831 These are elements encountered out of order
4832 which belong at places we haven't reached yet in actually
4833 writing the output.
4834 Will never hold tree nodes across GC runs. */
4835 static struct init_node *constructor_pending_elts;
4836
4837 /* The SPELLING_DEPTH of this constructor. */
4838 static int constructor_depth;
4839
4840 /* DECL node for which an initializer is being read.
4841 0 means we are reading a constructor expression
4842 such as (struct foo) {...}. */
4843 static tree constructor_decl;
4844
4845 /* Nonzero if this is an initializer for a top-level decl. */
4846 static int constructor_top_level;
4847
4848 /* Nonzero if there were any member designators in this initializer. */
4849 static int constructor_designated;
4850
4851 /* Nesting depth of designator list. */
4852 static int designator_depth;
4853
4854 /* Nonzero if there were diagnosed errors in this designator list. */
4855 static int designator_erroneous;
4856
4857 \f
4858 /* This stack has a level for each implicit or explicit level of
4859 structuring in the initializer, including the outermost one. It
4860 saves the values of most of the variables above. */
4861
4862 struct constructor_range_stack;
4863
4864 struct constructor_stack
4865 {
4866 struct constructor_stack *next;
4867 tree type;
4868 tree fields;
4869 tree index;
4870 tree max_index;
4871 tree unfilled_index;
4872 tree unfilled_fields;
4873 tree bit_index;
4874 VEC(constructor_elt,gc) *elements;
4875 struct init_node *pending_elts;
4876 int offset;
4877 int depth;
4878 /* If value nonzero, this value should replace the entire
4879 constructor at this level. */
4880 struct c_expr replacement_value;
4881 struct constructor_range_stack *range_stack;
4882 char constant;
4883 char simple;
4884 char implicit;
4885 char erroneous;
4886 char outer;
4887 char incremental;
4888 char designated;
4889 };
4890
4891 static struct constructor_stack *constructor_stack;
4892
4893 /* This stack represents designators from some range designator up to
4894 the last designator in the list. */
4895
4896 struct constructor_range_stack
4897 {
4898 struct constructor_range_stack *next, *prev;
4899 struct constructor_stack *stack;
4900 tree range_start;
4901 tree index;
4902 tree range_end;
4903 tree fields;
4904 };
4905
4906 static struct constructor_range_stack *constructor_range_stack;
4907
4908 /* This stack records separate initializers that are nested.
4909 Nested initializers can't happen in ANSI C, but GNU C allows them
4910 in cases like { ... (struct foo) { ... } ... }. */
4911
4912 struct initializer_stack
4913 {
4914 struct initializer_stack *next;
4915 tree decl;
4916 struct constructor_stack *constructor_stack;
4917 struct constructor_range_stack *constructor_range_stack;
4918 VEC(constructor_elt,gc) *elements;
4919 struct spelling *spelling;
4920 struct spelling *spelling_base;
4921 int spelling_size;
4922 char top_level;
4923 char require_constant_value;
4924 char require_constant_elements;
4925 };
4926
4927 static struct initializer_stack *initializer_stack;
4928 \f
4929 /* Prepare to parse and output the initializer for variable DECL. */
4930
4931 void
4932 start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
4933 {
4934 const char *locus;
4935 struct initializer_stack *p = XNEW (struct initializer_stack);
4936
4937 p->decl = constructor_decl;
4938 p->require_constant_value = require_constant_value;
4939 p->require_constant_elements = require_constant_elements;
4940 p->constructor_stack = constructor_stack;
4941 p->constructor_range_stack = constructor_range_stack;
4942 p->elements = constructor_elements;
4943 p->spelling = spelling;
4944 p->spelling_base = spelling_base;
4945 p->spelling_size = spelling_size;
4946 p->top_level = constructor_top_level;
4947 p->next = initializer_stack;
4948 initializer_stack = p;
4949
4950 constructor_decl = decl;
4951 constructor_designated = 0;
4952 constructor_top_level = top_level;
4953
4954 if (decl != 0 && decl != error_mark_node)
4955 {
4956 require_constant_value = TREE_STATIC (decl);
4957 require_constant_elements
4958 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
4959 /* For a scalar, you can always use any value to initialize,
4960 even within braces. */
4961 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4962 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4963 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4964 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4965 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4966 }
4967 else
4968 {
4969 require_constant_value = 0;
4970 require_constant_elements = 0;
4971 locus = "(anonymous)";
4972 }
4973
4974 constructor_stack = 0;
4975 constructor_range_stack = 0;
4976
4977 missing_braces_mentioned = 0;
4978
4979 spelling_base = 0;
4980 spelling_size = 0;
4981 RESTORE_SPELLING_DEPTH (0);
4982
4983 if (locus)
4984 push_string (locus);
4985 }
4986
4987 void
4988 finish_init (void)
4989 {
4990 struct initializer_stack *p = initializer_stack;
4991
4992 /* Free the whole constructor stack of this initializer. */
4993 while (constructor_stack)
4994 {
4995 struct constructor_stack *q = constructor_stack;
4996 constructor_stack = q->next;
4997 free (q);
4998 }
4999
5000 gcc_assert (!constructor_range_stack);
5001
5002 /* Pop back to the data of the outer initializer (if any). */
5003 free (spelling_base);
5004
5005 constructor_decl = p->decl;
5006 require_constant_value = p->require_constant_value;
5007 require_constant_elements = p->require_constant_elements;
5008 constructor_stack = p->constructor_stack;
5009 constructor_range_stack = p->constructor_range_stack;
5010 constructor_elements = p->elements;
5011 spelling = p->spelling;
5012 spelling_base = p->spelling_base;
5013 spelling_size = p->spelling_size;
5014 constructor_top_level = p->top_level;
5015 initializer_stack = p->next;
5016 free (p);
5017 }
5018 \f
5019 /* Call here when we see the initializer is surrounded by braces.
5020 This is instead of a call to push_init_level;
5021 it is matched by a call to pop_init_level.
5022
5023 TYPE is the type to initialize, for a constructor expression.
5024 For an initializer for a decl, TYPE is zero. */
5025
5026 void
5027 really_start_incremental_init (tree type)
5028 {
5029 struct constructor_stack *p = XNEW (struct constructor_stack);
5030
5031 if (type == 0)
5032 type = TREE_TYPE (constructor_decl);
5033
5034 if (targetm.vector_opaque_p (type))
5035 error ("opaque vector types cannot be initialized");
5036
5037 p->type = constructor_type;
5038 p->fields = constructor_fields;
5039 p->index = constructor_index;
5040 p->max_index = constructor_max_index;
5041 p->unfilled_index = constructor_unfilled_index;
5042 p->unfilled_fields = constructor_unfilled_fields;
5043 p->bit_index = constructor_bit_index;
5044 p->elements = constructor_elements;
5045 p->constant = constructor_constant;
5046 p->simple = constructor_simple;
5047 p->erroneous = constructor_erroneous;
5048 p->pending_elts = constructor_pending_elts;
5049 p->depth = constructor_depth;
5050 p->replacement_value.value = 0;
5051 p->replacement_value.original_code = ERROR_MARK;
5052 p->implicit = 0;
5053 p->range_stack = 0;
5054 p->outer = 0;
5055 p->incremental = constructor_incremental;
5056 p->designated = constructor_designated;
5057 p->next = 0;
5058 constructor_stack = p;
5059
5060 constructor_constant = 1;
5061 constructor_simple = 1;
5062 constructor_depth = SPELLING_DEPTH ();
5063 constructor_elements = 0;
5064 constructor_pending_elts = 0;
5065 constructor_type = type;
5066 constructor_incremental = 1;
5067 constructor_designated = 0;
5068 designator_depth = 0;
5069 designator_erroneous = 0;
5070
5071 if (TREE_CODE (constructor_type) == RECORD_TYPE
5072 || TREE_CODE (constructor_type) == UNION_TYPE)
5073 {
5074 constructor_fields = TYPE_FIELDS (constructor_type);
5075 /* Skip any nameless bit fields at the beginning. */
5076 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5077 && DECL_NAME (constructor_fields) == 0)
5078 constructor_fields = TREE_CHAIN (constructor_fields);
5079
5080 constructor_unfilled_fields = constructor_fields;
5081 constructor_bit_index = bitsize_zero_node;
5082 }
5083 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5084 {
5085 if (TYPE_DOMAIN (constructor_type))
5086 {
5087 constructor_max_index
5088 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5089
5090 /* Detect non-empty initializations of zero-length arrays. */
5091 if (constructor_max_index == NULL_TREE
5092 && TYPE_SIZE (constructor_type))
5093 constructor_max_index = build_int_cst (NULL_TREE, -1);
5094
5095 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5096 to initialize VLAs will cause a proper error; avoid tree
5097 checking errors as well by setting a safe value. */
5098 if (constructor_max_index
5099 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5100 constructor_max_index = build_int_cst (NULL_TREE, -1);
5101
5102 constructor_index
5103 = convert (bitsizetype,
5104 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5105 }
5106 else
5107 {
5108 constructor_index = bitsize_zero_node;
5109 constructor_max_index = NULL_TREE;
5110 }
5111
5112 constructor_unfilled_index = constructor_index;
5113 }
5114 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5115 {
5116 /* Vectors are like simple fixed-size arrays. */
5117 constructor_max_index =
5118 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5119 constructor_index = bitsize_zero_node;
5120 constructor_unfilled_index = constructor_index;
5121 }
5122 else
5123 {
5124 /* Handle the case of int x = {5}; */
5125 constructor_fields = constructor_type;
5126 constructor_unfilled_fields = constructor_type;
5127 }
5128 }
5129 \f
5130 /* Push down into a subobject, for initialization.
5131 If this is for an explicit set of braces, IMPLICIT is 0.
5132 If it is because the next element belongs at a lower level,
5133 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5134
5135 void
5136 push_init_level (int implicit)
5137 {
5138 struct constructor_stack *p;
5139 tree value = NULL_TREE;
5140
5141 /* If we've exhausted any levels that didn't have braces,
5142 pop them now. If implicit == 1, this will have been done in
5143 process_init_element; do not repeat it here because in the case
5144 of excess initializers for an empty aggregate this leads to an
5145 infinite cycle of popping a level and immediately recreating
5146 it. */
5147 if (implicit != 1)
5148 {
5149 while (constructor_stack->implicit)
5150 {
5151 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5152 || TREE_CODE (constructor_type) == UNION_TYPE)
5153 && constructor_fields == 0)
5154 process_init_element (pop_init_level (1));
5155 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5156 && constructor_max_index
5157 && tree_int_cst_lt (constructor_max_index,
5158 constructor_index))
5159 process_init_element (pop_init_level (1));
5160 else
5161 break;
5162 }
5163 }
5164
5165 /* Unless this is an explicit brace, we need to preserve previous
5166 content if any. */
5167 if (implicit)
5168 {
5169 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5170 || TREE_CODE (constructor_type) == UNION_TYPE)
5171 && constructor_fields)
5172 value = find_init_member (constructor_fields);
5173 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5174 value = find_init_member (constructor_index);
5175 }
5176
5177 p = XNEW (struct constructor_stack);
5178 p->type = constructor_type;
5179 p->fields = constructor_fields;
5180 p->index = constructor_index;
5181 p->max_index = constructor_max_index;
5182 p->unfilled_index = constructor_unfilled_index;
5183 p->unfilled_fields = constructor_unfilled_fields;
5184 p->bit_index = constructor_bit_index;
5185 p->elements = constructor_elements;
5186 p->constant = constructor_constant;
5187 p->simple = constructor_simple;
5188 p->erroneous = constructor_erroneous;
5189 p->pending_elts = constructor_pending_elts;
5190 p->depth = constructor_depth;
5191 p->replacement_value.value = 0;
5192 p->replacement_value.original_code = ERROR_MARK;
5193 p->implicit = implicit;
5194 p->outer = 0;
5195 p->incremental = constructor_incremental;
5196 p->designated = constructor_designated;
5197 p->next = constructor_stack;
5198 p->range_stack = 0;
5199 constructor_stack = p;
5200
5201 constructor_constant = 1;
5202 constructor_simple = 1;
5203 constructor_depth = SPELLING_DEPTH ();
5204 constructor_elements = 0;
5205 constructor_incremental = 1;
5206 constructor_designated = 0;
5207 constructor_pending_elts = 0;
5208 if (!implicit)
5209 {
5210 p->range_stack = constructor_range_stack;
5211 constructor_range_stack = 0;
5212 designator_depth = 0;
5213 designator_erroneous = 0;
5214 }
5215
5216 /* Don't die if an entire brace-pair level is superfluous
5217 in the containing level. */
5218 if (constructor_type == 0)
5219 ;
5220 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5221 || TREE_CODE (constructor_type) == UNION_TYPE)
5222 {
5223 /* Don't die if there are extra init elts at the end. */
5224 if (constructor_fields == 0)
5225 constructor_type = 0;
5226 else
5227 {
5228 constructor_type = TREE_TYPE (constructor_fields);
5229 push_member_name (constructor_fields);
5230 constructor_depth++;
5231 }
5232 }
5233 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5234 {
5235 constructor_type = TREE_TYPE (constructor_type);
5236 push_array_bounds (tree_low_cst (constructor_index, 1));
5237 constructor_depth++;
5238 }
5239
5240 if (constructor_type == 0)
5241 {
5242 error_init ("extra brace group at end of initializer");
5243 constructor_fields = 0;
5244 constructor_unfilled_fields = 0;
5245 return;
5246 }
5247
5248 if (value && TREE_CODE (value) == CONSTRUCTOR)
5249 {
5250 constructor_constant = TREE_CONSTANT (value);
5251 constructor_simple = TREE_STATIC (value);
5252 constructor_elements = CONSTRUCTOR_ELTS (value);
5253 if (!VEC_empty (constructor_elt, constructor_elements)
5254 && (TREE_CODE (constructor_type) == RECORD_TYPE
5255 || TREE_CODE (constructor_type) == ARRAY_TYPE))
5256 set_nonincremental_init ();
5257 }
5258
5259 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
5260 {
5261 missing_braces_mentioned = 1;
5262 warning_init ("missing braces around initializer");
5263 }
5264
5265 if (TREE_CODE (constructor_type) == RECORD_TYPE
5266 || TREE_CODE (constructor_type) == UNION_TYPE)
5267 {
5268 constructor_fields = TYPE_FIELDS (constructor_type);
5269 /* Skip any nameless bit fields at the beginning. */
5270 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5271 && DECL_NAME (constructor_fields) == 0)
5272 constructor_fields = TREE_CHAIN (constructor_fields);
5273
5274 constructor_unfilled_fields = constructor_fields;
5275 constructor_bit_index = bitsize_zero_node;
5276 }
5277 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5278 {
5279 /* Vectors are like simple fixed-size arrays. */
5280 constructor_max_index =
5281 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5282 constructor_index = convert (bitsizetype, integer_zero_node);
5283 constructor_unfilled_index = constructor_index;
5284 }
5285 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5286 {
5287 if (TYPE_DOMAIN (constructor_type))
5288 {
5289 constructor_max_index
5290 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5291
5292 /* Detect non-empty initializations of zero-length arrays. */
5293 if (constructor_max_index == NULL_TREE
5294 && TYPE_SIZE (constructor_type))
5295 constructor_max_index = build_int_cst (NULL_TREE, -1);
5296
5297 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5298 to initialize VLAs will cause a proper error; avoid tree
5299 checking errors as well by setting a safe value. */
5300 if (constructor_max_index
5301 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5302 constructor_max_index = build_int_cst (NULL_TREE, -1);
5303
5304 constructor_index
5305 = convert (bitsizetype,
5306 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5307 }
5308 else
5309 constructor_index = bitsize_zero_node;
5310
5311 constructor_unfilled_index = constructor_index;
5312 if (value && TREE_CODE (value) == STRING_CST)
5313 {
5314 /* We need to split the char/wchar array into individual
5315 characters, so that we don't have to special case it
5316 everywhere. */
5317 set_nonincremental_init_from_string (value);
5318 }
5319 }
5320 else
5321 {
5322 if (constructor_type != error_mark_node)
5323 warning_init ("braces around scalar initializer");
5324 constructor_fields = constructor_type;
5325 constructor_unfilled_fields = constructor_type;
5326 }
5327 }
5328
5329 /* At the end of an implicit or explicit brace level,
5330 finish up that level of constructor. If a single expression
5331 with redundant braces initialized that level, return the
5332 c_expr structure for that expression. Otherwise, the original_code
5333 element is set to ERROR_MARK.
5334 If we were outputting the elements as they are read, return 0 as the value
5335 from inner levels (process_init_element ignores that),
5336 but return error_mark_node as the value from the outermost level
5337 (that's what we want to put in DECL_INITIAL).
5338 Otherwise, return a CONSTRUCTOR expression as the value. */
5339
5340 struct c_expr
5341 pop_init_level (int implicit)
5342 {
5343 struct constructor_stack *p;
5344 struct c_expr ret;
5345 ret.value = 0;
5346 ret.original_code = ERROR_MARK;
5347
5348 if (implicit == 0)
5349 {
5350 /* When we come to an explicit close brace,
5351 pop any inner levels that didn't have explicit braces. */
5352 while (constructor_stack->implicit)
5353 process_init_element (pop_init_level (1));
5354
5355 gcc_assert (!constructor_range_stack);
5356 }
5357
5358 /* Now output all pending elements. */
5359 constructor_incremental = 1;
5360 output_pending_init_elements (1);
5361
5362 p = constructor_stack;
5363
5364 /* Error for initializing a flexible array member, or a zero-length
5365 array member in an inappropriate context. */
5366 if (constructor_type && constructor_fields
5367 && TREE_CODE (constructor_type) == ARRAY_TYPE
5368 && TYPE_DOMAIN (constructor_type)
5369 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5370 {
5371 /* Silently discard empty initializations. The parser will
5372 already have pedwarned for empty brackets. */
5373 if (integer_zerop (constructor_unfilled_index))
5374 constructor_type = NULL_TREE;
5375 else
5376 {
5377 gcc_assert (!TYPE_SIZE (constructor_type));
5378
5379 if (constructor_depth > 2)
5380 error_init ("initialization of flexible array member in a nested context");
5381 else if (pedantic)
5382 pedwarn_init ("initialization of a flexible array member");
5383
5384 /* We have already issued an error message for the existence
5385 of a flexible array member not at the end of the structure.
5386 Discard the initializer so that we do not die later. */
5387 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
5388 constructor_type = NULL_TREE;
5389 }
5390 }
5391
5392 /* Warn when some struct elements are implicitly initialized to zero. */
5393 if (warn_missing_field_initializers
5394 && constructor_type
5395 && TREE_CODE (constructor_type) == RECORD_TYPE
5396 && constructor_unfilled_fields)
5397 {
5398 /* Do not warn for flexible array members or zero-length arrays. */
5399 while (constructor_unfilled_fields
5400 && (!DECL_SIZE (constructor_unfilled_fields)
5401 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
5402 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5403
5404 /* Do not warn if this level of the initializer uses member
5405 designators; it is likely to be deliberate. */
5406 if (constructor_unfilled_fields && !constructor_designated)
5407 {
5408 push_member_name (constructor_unfilled_fields);
5409 warning_init ("missing initializer");
5410 RESTORE_SPELLING_DEPTH (constructor_depth);
5411 }
5412 }
5413
5414 /* Pad out the end of the structure. */
5415 if (p->replacement_value.value)
5416 /* If this closes a superfluous brace pair,
5417 just pass out the element between them. */
5418 ret = p->replacement_value;
5419 else if (constructor_type == 0)
5420 ;
5421 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5422 && TREE_CODE (constructor_type) != UNION_TYPE
5423 && TREE_CODE (constructor_type) != ARRAY_TYPE
5424 && TREE_CODE (constructor_type) != VECTOR_TYPE)
5425 {
5426 /* A nonincremental scalar initializer--just return
5427 the element, after verifying there is just one. */
5428 if (VEC_empty (constructor_elt,constructor_elements))
5429 {
5430 if (!constructor_erroneous)
5431 error_init ("empty scalar initializer");
5432 ret.value = error_mark_node;
5433 }
5434 else if (VEC_length (constructor_elt,constructor_elements) != 1)
5435 {
5436 error_init ("extra elements in scalar initializer");
5437 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
5438 }
5439 else
5440 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
5441 }
5442 else
5443 {
5444 if (constructor_erroneous)
5445 ret.value = error_mark_node;
5446 else
5447 {
5448 ret.value = build_constructor (constructor_type,
5449 constructor_elements);
5450 if (constructor_constant)
5451 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1;
5452 if (constructor_constant && constructor_simple)
5453 TREE_STATIC (ret.value) = 1;
5454 }
5455 }
5456
5457 constructor_type = p->type;
5458 constructor_fields = p->fields;
5459 constructor_index = p->index;
5460 constructor_max_index = p->max_index;
5461 constructor_unfilled_index = p->unfilled_index;
5462 constructor_unfilled_fields = p->unfilled_fields;
5463 constructor_bit_index = p->bit_index;
5464 constructor_elements = p->elements;
5465 constructor_constant = p->constant;
5466 constructor_simple = p->simple;
5467 constructor_erroneous = p->erroneous;
5468 constructor_incremental = p->incremental;
5469 constructor_designated = p->designated;
5470 constructor_pending_elts = p->pending_elts;
5471 constructor_depth = p->depth;
5472 if (!p->implicit)
5473 constructor_range_stack = p->range_stack;
5474 RESTORE_SPELLING_DEPTH (constructor_depth);
5475
5476 constructor_stack = p->next;
5477 free (p);
5478
5479 if (ret.value == 0 && constructor_stack == 0)
5480 ret.value = error_mark_node;
5481 return ret;
5482 }
5483
5484 /* Common handling for both array range and field name designators.
5485 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5486
5487 static int
5488 set_designator (int array)
5489 {
5490 tree subtype;
5491 enum tree_code subcode;
5492
5493 /* Don't die if an entire brace-pair level is superfluous
5494 in the containing level. */
5495 if (constructor_type == 0)
5496 return 1;
5497
5498 /* If there were errors in this designator list already, bail out
5499 silently. */
5500 if (designator_erroneous)
5501 return 1;
5502
5503 if (!designator_depth)
5504 {
5505 gcc_assert (!constructor_range_stack);
5506
5507 /* Designator list starts at the level of closest explicit
5508 braces. */
5509 while (constructor_stack->implicit)
5510 process_init_element (pop_init_level (1));
5511 constructor_designated = 1;
5512 return 0;
5513 }
5514
5515 switch (TREE_CODE (constructor_type))
5516 {
5517 case RECORD_TYPE:
5518 case UNION_TYPE:
5519 subtype = TREE_TYPE (constructor_fields);
5520 if (subtype != error_mark_node)
5521 subtype = TYPE_MAIN_VARIANT (subtype);
5522 break;
5523 case ARRAY_TYPE:
5524 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5525 break;
5526 default:
5527 gcc_unreachable ();
5528 }
5529
5530 subcode = TREE_CODE (subtype);
5531 if (array && subcode != ARRAY_TYPE)
5532 {
5533 error_init ("array index in non-array initializer");
5534 return 1;
5535 }
5536 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
5537 {
5538 error_init ("field name not in record or union initializer");
5539 return 1;
5540 }
5541
5542 constructor_designated = 1;
5543 push_init_level (2);
5544 return 0;
5545 }
5546
5547 /* If there are range designators in designator list, push a new designator
5548 to constructor_range_stack. RANGE_END is end of such stack range or
5549 NULL_TREE if there is no range designator at this level. */
5550
5551 static void
5552 push_range_stack (tree range_end)
5553 {
5554 struct constructor_range_stack *p;
5555
5556 p = GGC_NEW (struct constructor_range_stack);
5557 p->prev = constructor_range_stack;
5558 p->next = 0;
5559 p->fields = constructor_fields;
5560 p->range_start = constructor_index;
5561 p->index = constructor_index;
5562 p->stack = constructor_stack;
5563 p->range_end = range_end;
5564 if (constructor_range_stack)
5565 constructor_range_stack->next = p;
5566 constructor_range_stack = p;
5567 }
5568
5569 /* Within an array initializer, specify the next index to be initialized.
5570 FIRST is that index. If LAST is nonzero, then initialize a range
5571 of indices, running from FIRST through LAST. */
5572
5573 void
5574 set_init_index (tree first, tree last)
5575 {
5576 if (set_designator (1))
5577 return;
5578
5579 designator_erroneous = 1;
5580
5581 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
5582 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
5583 {
5584 error_init ("array index in initializer not of integer type");
5585 return;
5586 }
5587
5588 if (TREE_CODE (first) != INTEGER_CST)
5589 error_init ("nonconstant array index in initializer");
5590 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5591 error_init ("nonconstant array index in initializer");
5592 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5593 error_init ("array index in non-array initializer");
5594 else if (tree_int_cst_sgn (first) == -1)
5595 error_init ("array index in initializer exceeds array bounds");
5596 else if (constructor_max_index
5597 && tree_int_cst_lt (constructor_max_index, first))
5598 error_init ("array index in initializer exceeds array bounds");
5599 else
5600 {
5601 constructor_index = convert (bitsizetype, first);
5602
5603 if (last)
5604 {
5605 if (tree_int_cst_equal (first, last))
5606 last = 0;
5607 else if (tree_int_cst_lt (last, first))
5608 {
5609 error_init ("empty index range in initializer");
5610 last = 0;
5611 }
5612 else
5613 {
5614 last = convert (bitsizetype, last);
5615 if (constructor_max_index != 0
5616 && tree_int_cst_lt (constructor_max_index, last))
5617 {
5618 error_init ("array index range in initializer exceeds array bounds");
5619 last = 0;
5620 }
5621 }
5622 }
5623
5624 designator_depth++;
5625 designator_erroneous = 0;
5626 if (constructor_range_stack || last)
5627 push_range_stack (last);
5628 }
5629 }
5630
5631 /* Within a struct initializer, specify the next field to be initialized. */
5632
5633 void
5634 set_init_label (tree fieldname)
5635 {
5636 tree tail;
5637
5638 if (set_designator (0))
5639 return;
5640
5641 designator_erroneous = 1;
5642
5643 if (TREE_CODE (constructor_type) != RECORD_TYPE
5644 && TREE_CODE (constructor_type) != UNION_TYPE)
5645 {
5646 error_init ("field name not in record or union initializer");
5647 return;
5648 }
5649
5650 for (tail = TYPE_FIELDS (constructor_type); tail;
5651 tail = TREE_CHAIN (tail))
5652 {
5653 if (DECL_NAME (tail) == fieldname)
5654 break;
5655 }
5656
5657 if (tail == 0)
5658 error ("unknown field %qE specified in initializer", fieldname);
5659 else
5660 {
5661 constructor_fields = tail;
5662 designator_depth++;
5663 designator_erroneous = 0;
5664 if (constructor_range_stack)
5665 push_range_stack (NULL_TREE);
5666 }
5667 }
5668 \f
5669 /* Add a new initializer to the tree of pending initializers. PURPOSE
5670 identifies the initializer, either array index or field in a structure.
5671 VALUE is the value of that index or field. */
5672
5673 static void
5674 add_pending_init (tree purpose, tree value)
5675 {
5676 struct init_node *p, **q, *r;
5677
5678 q = &constructor_pending_elts;
5679 p = 0;
5680
5681 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5682 {
5683 while (*q != 0)
5684 {
5685 p = *q;
5686 if (tree_int_cst_lt (purpose, p->purpose))
5687 q = &p->left;
5688 else if (tree_int_cst_lt (p->purpose, purpose))
5689 q = &p->right;
5690 else
5691 {
5692 if (TREE_SIDE_EFFECTS (p->value))
5693 warning_init ("initialized field with side-effects overwritten");
5694 else if (warn_override_init)
5695 warning_init ("initialized field overwritten");
5696 p->value = value;
5697 return;
5698 }
5699 }
5700 }
5701 else
5702 {
5703 tree bitpos;
5704
5705 bitpos = bit_position (purpose);
5706 while (*q != NULL)
5707 {
5708 p = *q;
5709 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5710 q = &p->left;
5711 else if (p->purpose != purpose)
5712 q = &p->right;
5713 else
5714 {
5715 if (TREE_SIDE_EFFECTS (p->value))
5716 warning_init ("initialized field with side-effects overwritten");
5717 else if (warn_override_init)
5718 warning_init ("initialized field overwritten");
5719 p->value = value;
5720 return;
5721 }
5722 }
5723 }
5724
5725 r = GGC_NEW (struct init_node);
5726 r->purpose = purpose;
5727 r->value = value;
5728
5729 *q = r;
5730 r->parent = p;
5731 r->left = 0;
5732 r->right = 0;
5733 r->balance = 0;
5734
5735 while (p)
5736 {
5737 struct init_node *s;
5738
5739 if (r == p->left)
5740 {
5741 if (p->balance == 0)
5742 p->balance = -1;
5743 else if (p->balance < 0)
5744 {
5745 if (r->balance < 0)
5746 {
5747 /* L rotation. */
5748 p->left = r->right;
5749 if (p->left)
5750 p->left->parent = p;
5751 r->right = p;
5752
5753 p->balance = 0;
5754 r->balance = 0;
5755
5756 s = p->parent;
5757 p->parent = r;
5758 r->parent = s;
5759 if (s)
5760 {
5761 if (s->left == p)
5762 s->left = r;
5763 else
5764 s->right = r;
5765 }
5766 else
5767 constructor_pending_elts = r;
5768 }
5769 else
5770 {
5771 /* LR rotation. */
5772 struct init_node *t = r->right;
5773
5774 r->right = t->left;
5775 if (r->right)
5776 r->right->parent = r;
5777 t->left = r;
5778
5779 p->left = t->right;
5780 if (p->left)
5781 p->left->parent = p;
5782 t->right = p;
5783
5784 p->balance = t->balance < 0;
5785 r->balance = -(t->balance > 0);
5786 t->balance = 0;
5787
5788 s = p->parent;
5789 p->parent = t;
5790 r->parent = t;
5791 t->parent = s;
5792 if (s)
5793 {
5794 if (s->left == p)
5795 s->left = t;
5796 else
5797 s->right = t;
5798 }
5799 else
5800 constructor_pending_elts = t;
5801 }
5802 break;
5803 }
5804 else
5805 {
5806 /* p->balance == +1; growth of left side balances the node. */
5807 p->balance = 0;
5808 break;
5809 }
5810 }
5811 else /* r == p->right */
5812 {
5813 if (p->balance == 0)
5814 /* Growth propagation from right side. */
5815 p->balance++;
5816 else if (p->balance > 0)
5817 {
5818 if (r->balance > 0)
5819 {
5820 /* R rotation. */
5821 p->right = r->left;
5822 if (p->right)
5823 p->right->parent = p;
5824 r->left = p;
5825
5826 p->balance = 0;
5827 r->balance = 0;
5828
5829 s = p->parent;
5830 p->parent = r;
5831 r->parent = s;
5832 if (s)
5833 {
5834 if (s->left == p)
5835 s->left = r;
5836 else
5837 s->right = r;
5838 }
5839 else
5840 constructor_pending_elts = r;
5841 }
5842 else /* r->balance == -1 */
5843 {
5844 /* RL rotation */
5845 struct init_node *t = r->left;
5846
5847 r->left = t->right;
5848 if (r->left)
5849 r->left->parent = r;
5850 t->right = r;
5851
5852 p->right = t->left;
5853 if (p->right)
5854 p->right->parent = p;
5855 t->left = p;
5856
5857 r->balance = (t->balance < 0);
5858 p->balance = -(t->balance > 0);
5859 t->balance = 0;
5860
5861 s = p->parent;
5862 p->parent = t;
5863 r->parent = t;
5864 t->parent = s;
5865 if (s)
5866 {
5867 if (s->left == p)
5868 s->left = t;
5869 else
5870 s->right = t;
5871 }
5872 else
5873 constructor_pending_elts = t;
5874 }
5875 break;
5876 }
5877 else
5878 {
5879 /* p->balance == -1; growth of right side balances the node. */
5880 p->balance = 0;
5881 break;
5882 }
5883 }
5884
5885 r = p;
5886 p = p->parent;
5887 }
5888 }
5889
5890 /* Build AVL tree from a sorted chain. */
5891
5892 static void
5893 set_nonincremental_init (void)
5894 {
5895 unsigned HOST_WIDE_INT ix;
5896 tree index, value;
5897
5898 if (TREE_CODE (constructor_type) != RECORD_TYPE
5899 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5900 return;
5901
5902 FOR_EACH_CONSTRUCTOR_ELT (constructor_elements, ix, index, value)
5903 add_pending_init (index, value);
5904 constructor_elements = 0;
5905 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5906 {
5907 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
5908 /* Skip any nameless bit fields at the beginning. */
5909 while (constructor_unfilled_fields != 0
5910 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5911 && DECL_NAME (constructor_unfilled_fields) == 0)
5912 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5913
5914 }
5915 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5916 {
5917 if (TYPE_DOMAIN (constructor_type))
5918 constructor_unfilled_index
5919 = convert (bitsizetype,
5920 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5921 else
5922 constructor_unfilled_index = bitsize_zero_node;
5923 }
5924 constructor_incremental = 0;
5925 }
5926
5927 /* Build AVL tree from a string constant. */
5928
5929 static void
5930 set_nonincremental_init_from_string (tree str)
5931 {
5932 tree value, purpose, type;
5933 HOST_WIDE_INT val[2];
5934 const char *p, *end;
5935 int byte, wchar_bytes, charwidth, bitpos;
5936
5937 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
5938
5939 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5940 == TYPE_PRECISION (char_type_node))
5941 wchar_bytes = 1;
5942 else
5943 {
5944 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5945 == TYPE_PRECISION (wchar_type_node));
5946 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
5947 }
5948 charwidth = TYPE_PRECISION (char_type_node);
5949 type = TREE_TYPE (constructor_type);
5950 p = TREE_STRING_POINTER (str);
5951 end = p + TREE_STRING_LENGTH (str);
5952
5953 for (purpose = bitsize_zero_node;
5954 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
5955 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
5956 {
5957 if (wchar_bytes == 1)
5958 {
5959 val[1] = (unsigned char) *p++;
5960 val[0] = 0;
5961 }
5962 else
5963 {
5964 val[0] = 0;
5965 val[1] = 0;
5966 for (byte = 0; byte < wchar_bytes; byte++)
5967 {
5968 if (BYTES_BIG_ENDIAN)
5969 bitpos = (wchar_bytes - byte - 1) * charwidth;
5970 else
5971 bitpos = byte * charwidth;
5972 val[bitpos < HOST_BITS_PER_WIDE_INT]
5973 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
5974 << (bitpos % HOST_BITS_PER_WIDE_INT);
5975 }
5976 }
5977
5978 if (!TYPE_UNSIGNED (type))
5979 {
5980 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
5981 if (bitpos < HOST_BITS_PER_WIDE_INT)
5982 {
5983 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
5984 {
5985 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
5986 val[0] = -1;
5987 }
5988 }
5989 else if (bitpos == HOST_BITS_PER_WIDE_INT)
5990 {
5991 if (val[1] < 0)
5992 val[0] = -1;
5993 }
5994 else if (val[0] & (((HOST_WIDE_INT) 1)
5995 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
5996 val[0] |= ((HOST_WIDE_INT) -1)
5997 << (bitpos - HOST_BITS_PER_WIDE_INT);
5998 }
5999
6000 value = build_int_cst_wide (type, val[1], val[0]);
6001 add_pending_init (purpose, value);
6002 }
6003
6004 constructor_incremental = 0;
6005 }
6006
6007 /* Return value of FIELD in pending initializer or zero if the field was
6008 not initialized yet. */
6009
6010 static tree
6011 find_init_member (tree field)
6012 {
6013 struct init_node *p;
6014
6015 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6016 {
6017 if (constructor_incremental
6018 && tree_int_cst_lt (field, constructor_unfilled_index))
6019 set_nonincremental_init ();
6020
6021 p = constructor_pending_elts;
6022 while (p)
6023 {
6024 if (tree_int_cst_lt (field, p->purpose))
6025 p = p->left;
6026 else if (tree_int_cst_lt (p->purpose, field))
6027 p = p->right;
6028 else
6029 return p->value;
6030 }
6031 }
6032 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6033 {
6034 tree bitpos = bit_position (field);
6035
6036 if (constructor_incremental
6037 && (!constructor_unfilled_fields
6038 || tree_int_cst_lt (bitpos,
6039 bit_position (constructor_unfilled_fields))))
6040 set_nonincremental_init ();
6041
6042 p = constructor_pending_elts;
6043 while (p)
6044 {
6045 if (field == p->purpose)
6046 return p->value;
6047 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
6048 p = p->left;
6049 else
6050 p = p->right;
6051 }
6052 }
6053 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6054 {
6055 if (!VEC_empty (constructor_elt, constructor_elements)
6056 && (VEC_last (constructor_elt, constructor_elements)->index
6057 == field))
6058 return VEC_last (constructor_elt, constructor_elements)->value;
6059 }
6060 return 0;
6061 }
6062
6063 /* "Output" the next constructor element.
6064 At top level, really output it to assembler code now.
6065 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6066 TYPE is the data type that the containing data type wants here.
6067 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6068 If VALUE is a string constant, STRICT_STRING is true if it is
6069 unparenthesized or we should not warn here for it being parenthesized.
6070 For other types of VALUE, STRICT_STRING is not used.
6071
6072 PENDING if non-nil means output pending elements that belong
6073 right after this element. (PENDING is normally 1;
6074 it is 0 while outputting pending elements, to avoid recursion.) */
6075
6076 static void
6077 output_init_element (tree value, bool strict_string, tree type, tree field,
6078 int pending)
6079 {
6080 constructor_elt *celt;
6081
6082 if (type == error_mark_node || value == error_mark_node)
6083 {
6084 constructor_erroneous = 1;
6085 return;
6086 }
6087 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
6088 && (TREE_CODE (value) == STRING_CST
6089 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR)
6090 && !(TREE_CODE (value) == STRING_CST
6091 && TREE_CODE (type) == ARRAY_TYPE
6092 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
6093 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
6094 TYPE_MAIN_VARIANT (type)))
6095 value = array_to_pointer_conversion (value);
6096
6097 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
6098 && require_constant_value && !flag_isoc99 && pending)
6099 {
6100 /* As an extension, allow initializing objects with static storage
6101 duration with compound literals (which are then treated just as
6102 the brace enclosed list they contain). */
6103 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
6104 value = DECL_INITIAL (decl);
6105 }
6106
6107 if (value == error_mark_node)
6108 constructor_erroneous = 1;
6109 else if (!TREE_CONSTANT (value))
6110 constructor_constant = 0;
6111 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
6112 || ((TREE_CODE (constructor_type) == RECORD_TYPE
6113 || TREE_CODE (constructor_type) == UNION_TYPE)
6114 && DECL_C_BIT_FIELD (field)
6115 && TREE_CODE (value) != INTEGER_CST))
6116 constructor_simple = 0;
6117
6118 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
6119 {
6120 if (require_constant_value)
6121 {
6122 error_init ("initializer element is not constant");
6123 value = error_mark_node;
6124 }
6125 else if (require_constant_elements)
6126 pedwarn ("initializer element is not computable at load time");
6127 }
6128
6129 /* If this field is empty (and not at the end of structure),
6130 don't do anything other than checking the initializer. */
6131 if (field
6132 && (TREE_TYPE (field) == error_mark_node
6133 || (COMPLETE_TYPE_P (TREE_TYPE (field))
6134 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
6135 && (TREE_CODE (constructor_type) == ARRAY_TYPE
6136 || TREE_CHAIN (field)))))
6137 return;
6138
6139 value = digest_init (type, value, strict_string, require_constant_value);
6140 if (value == error_mark_node)
6141 {
6142 constructor_erroneous = 1;
6143 return;
6144 }
6145
6146 /* If this element doesn't come next in sequence,
6147 put it on constructor_pending_elts. */
6148 if (TREE_CODE (constructor_type) == ARRAY_TYPE
6149 && (!constructor_incremental
6150 || !tree_int_cst_equal (field, constructor_unfilled_index)))
6151 {
6152 if (constructor_incremental
6153 && tree_int_cst_lt (field, constructor_unfilled_index))
6154 set_nonincremental_init ();
6155
6156 add_pending_init (field, value);
6157 return;
6158 }
6159 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6160 && (!constructor_incremental
6161 || field != constructor_unfilled_fields))
6162 {
6163 /* We do this for records but not for unions. In a union,
6164 no matter which field is specified, it can be initialized
6165 right away since it starts at the beginning of the union. */
6166 if (constructor_incremental)
6167 {
6168 if (!constructor_unfilled_fields)
6169 set_nonincremental_init ();
6170 else
6171 {
6172 tree bitpos, unfillpos;
6173
6174 bitpos = bit_position (field);
6175 unfillpos = bit_position (constructor_unfilled_fields);
6176
6177 if (tree_int_cst_lt (bitpos, unfillpos))
6178 set_nonincremental_init ();
6179 }
6180 }
6181
6182 add_pending_init (field, value);
6183 return;
6184 }
6185 else if (TREE_CODE (constructor_type) == UNION_TYPE
6186 && !VEC_empty (constructor_elt, constructor_elements))
6187 {
6188 if (TREE_SIDE_EFFECTS (VEC_last (constructor_elt,
6189 constructor_elements)->value))
6190 warning_init ("initialized field with side-effects overwritten");
6191 else if (warn_override_init)
6192 warning_init ("initialized field overwritten");
6193
6194 /* We can have just one union field set. */
6195 constructor_elements = 0;
6196 }
6197
6198 /* Otherwise, output this element either to
6199 constructor_elements or to the assembler file. */
6200
6201 celt = VEC_safe_push (constructor_elt, gc, constructor_elements, NULL);
6202 celt->index = field;
6203 celt->value = value;
6204
6205 /* Advance the variable that indicates sequential elements output. */
6206 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6207 constructor_unfilled_index
6208 = size_binop (PLUS_EXPR, constructor_unfilled_index,
6209 bitsize_one_node);
6210 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6211 {
6212 constructor_unfilled_fields
6213 = TREE_CHAIN (constructor_unfilled_fields);
6214
6215 /* Skip any nameless bit fields. */
6216 while (constructor_unfilled_fields != 0
6217 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6218 && DECL_NAME (constructor_unfilled_fields) == 0)
6219 constructor_unfilled_fields =
6220 TREE_CHAIN (constructor_unfilled_fields);
6221 }
6222 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6223 constructor_unfilled_fields = 0;
6224
6225 /* Now output any pending elements which have become next. */
6226 if (pending)
6227 output_pending_init_elements (0);
6228 }
6229
6230 /* Output any pending elements which have become next.
6231 As we output elements, constructor_unfilled_{fields,index}
6232 advances, which may cause other elements to become next;
6233 if so, they too are output.
6234
6235 If ALL is 0, we return when there are
6236 no more pending elements to output now.
6237
6238 If ALL is 1, we output space as necessary so that
6239 we can output all the pending elements. */
6240
6241 static void
6242 output_pending_init_elements (int all)
6243 {
6244 struct init_node *elt = constructor_pending_elts;
6245 tree next;
6246
6247 retry:
6248
6249 /* Look through the whole pending tree.
6250 If we find an element that should be output now,
6251 output it. Otherwise, set NEXT to the element
6252 that comes first among those still pending. */
6253
6254 next = 0;
6255 while (elt)
6256 {
6257 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6258 {
6259 if (tree_int_cst_equal (elt->purpose,
6260 constructor_unfilled_index))
6261 output_init_element (elt->value, true,
6262 TREE_TYPE (constructor_type),
6263 constructor_unfilled_index, 0);
6264 else if (tree_int_cst_lt (constructor_unfilled_index,
6265 elt->purpose))
6266 {
6267 /* Advance to the next smaller node. */
6268 if (elt->left)
6269 elt = elt->left;
6270 else
6271 {
6272 /* We have reached the smallest node bigger than the
6273 current unfilled index. Fill the space first. */
6274 next = elt->purpose;
6275 break;
6276 }
6277 }
6278 else
6279 {
6280 /* Advance to the next bigger node. */
6281 if (elt->right)
6282 elt = elt->right;
6283 else
6284 {
6285 /* We have reached the biggest node in a subtree. Find
6286 the parent of it, which is the next bigger node. */
6287 while (elt->parent && elt->parent->right == elt)
6288 elt = elt->parent;
6289 elt = elt->parent;
6290 if (elt && tree_int_cst_lt (constructor_unfilled_index,
6291 elt->purpose))
6292 {
6293 next = elt->purpose;
6294 break;
6295 }
6296 }
6297 }
6298 }
6299 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6300 || TREE_CODE (constructor_type) == UNION_TYPE)
6301 {
6302 tree ctor_unfilled_bitpos, elt_bitpos;
6303
6304 /* If the current record is complete we are done. */
6305 if (constructor_unfilled_fields == 0)
6306 break;
6307
6308 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
6309 elt_bitpos = bit_position (elt->purpose);
6310 /* We can't compare fields here because there might be empty
6311 fields in between. */
6312 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
6313 {
6314 constructor_unfilled_fields = elt->purpose;
6315 output_init_element (elt->value, true, TREE_TYPE (elt->purpose),
6316 elt->purpose, 0);
6317 }
6318 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
6319 {
6320 /* Advance to the next smaller node. */
6321 if (elt->left)
6322 elt = elt->left;
6323 else
6324 {
6325 /* We have reached the smallest node bigger than the
6326 current unfilled field. Fill the space first. */
6327 next = elt->purpose;
6328 break;
6329 }
6330 }
6331 else
6332 {
6333 /* Advance to the next bigger node. */
6334 if (elt->right)
6335 elt = elt->right;
6336 else
6337 {
6338 /* We have reached the biggest node in a subtree. Find
6339 the parent of it, which is the next bigger node. */
6340 while (elt->parent && elt->parent->right == elt)
6341 elt = elt->parent;
6342 elt = elt->parent;
6343 if (elt
6344 && (tree_int_cst_lt (ctor_unfilled_bitpos,
6345 bit_position (elt->purpose))))
6346 {
6347 next = elt->purpose;
6348 break;
6349 }
6350 }
6351 }
6352 }
6353 }
6354
6355 /* Ordinarily return, but not if we want to output all
6356 and there are elements left. */
6357 if (!(all && next != 0))
6358 return;
6359
6360 /* If it's not incremental, just skip over the gap, so that after
6361 jumping to retry we will output the next successive element. */
6362 if (TREE_CODE (constructor_type) == RECORD_TYPE
6363 || TREE_CODE (constructor_type) == UNION_TYPE)
6364 constructor_unfilled_fields = next;
6365 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6366 constructor_unfilled_index = next;
6367
6368 /* ELT now points to the node in the pending tree with the next
6369 initializer to output. */
6370 goto retry;
6371 }
6372 \f
6373 /* Add one non-braced element to the current constructor level.
6374 This adjusts the current position within the constructor's type.
6375 This may also start or terminate implicit levels
6376 to handle a partly-braced initializer.
6377
6378 Once this has found the correct level for the new element,
6379 it calls output_init_element. */
6380
6381 void
6382 process_init_element (struct c_expr value)
6383 {
6384 tree orig_value = value.value;
6385 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
6386 bool strict_string = value.original_code == STRING_CST;
6387
6388 designator_depth = 0;
6389 designator_erroneous = 0;
6390
6391 /* Handle superfluous braces around string cst as in
6392 char x[] = {"foo"}; */
6393 if (string_flag
6394 && constructor_type
6395 && TREE_CODE (constructor_type) == ARRAY_TYPE
6396 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
6397 && integer_zerop (constructor_unfilled_index))
6398 {
6399 if (constructor_stack->replacement_value.value)
6400 error_init ("excess elements in char array initializer");
6401 constructor_stack->replacement_value = value;
6402 return;
6403 }
6404
6405 if (constructor_stack->replacement_value.value != 0)
6406 {
6407 error_init ("excess elements in struct initializer");
6408 return;
6409 }
6410
6411 /* Ignore elements of a brace group if it is entirely superfluous
6412 and has already been diagnosed. */
6413 if (constructor_type == 0)
6414 return;
6415
6416 /* If we've exhausted any levels that didn't have braces,
6417 pop them now. */
6418 while (constructor_stack->implicit)
6419 {
6420 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6421 || TREE_CODE (constructor_type) == UNION_TYPE)
6422 && constructor_fields == 0)
6423 process_init_element (pop_init_level (1));
6424 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6425 && (constructor_max_index == 0
6426 || tree_int_cst_lt (constructor_max_index,
6427 constructor_index)))
6428 process_init_element (pop_init_level (1));
6429 else
6430 break;
6431 }
6432
6433 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6434 if (constructor_range_stack)
6435 {
6436 /* If value is a compound literal and we'll be just using its
6437 content, don't put it into a SAVE_EXPR. */
6438 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
6439 || !require_constant_value
6440 || flag_isoc99)
6441 value.value = save_expr (value.value);
6442 }
6443
6444 while (1)
6445 {
6446 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6447 {
6448 tree fieldtype;
6449 enum tree_code fieldcode;
6450
6451 if (constructor_fields == 0)
6452 {
6453 pedwarn_init ("excess elements in struct initializer");
6454 break;
6455 }
6456
6457 fieldtype = TREE_TYPE (constructor_fields);
6458 if (fieldtype != error_mark_node)
6459 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6460 fieldcode = TREE_CODE (fieldtype);
6461
6462 /* Error for non-static initialization of a flexible array member. */
6463 if (fieldcode == ARRAY_TYPE
6464 && !require_constant_value
6465 && TYPE_SIZE (fieldtype) == NULL_TREE
6466 && TREE_CHAIN (constructor_fields) == NULL_TREE)
6467 {
6468 error_init ("non-static initialization of a flexible array member");
6469 break;
6470 }
6471
6472 /* Accept a string constant to initialize a subarray. */
6473 if (value.value != 0
6474 && fieldcode == ARRAY_TYPE
6475 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6476 && string_flag)
6477 value.value = orig_value;
6478 /* Otherwise, if we have come to a subaggregate,
6479 and we don't have an element of its type, push into it. */
6480 else if (value.value != 0
6481 && value.value != error_mark_node
6482 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6483 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6484 || fieldcode == UNION_TYPE))
6485 {
6486 push_init_level (1);
6487 continue;
6488 }
6489
6490 if (value.value)
6491 {
6492 push_member_name (constructor_fields);
6493 output_init_element (value.value, strict_string,
6494 fieldtype, constructor_fields, 1);
6495 RESTORE_SPELLING_DEPTH (constructor_depth);
6496 }
6497 else
6498 /* Do the bookkeeping for an element that was
6499 directly output as a constructor. */
6500 {
6501 /* For a record, keep track of end position of last field. */
6502 if (DECL_SIZE (constructor_fields))
6503 constructor_bit_index
6504 = size_binop (PLUS_EXPR,
6505 bit_position (constructor_fields),
6506 DECL_SIZE (constructor_fields));
6507
6508 /* If the current field was the first one not yet written out,
6509 it isn't now, so update. */
6510 if (constructor_unfilled_fields == constructor_fields)
6511 {
6512 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6513 /* Skip any nameless bit fields. */
6514 while (constructor_unfilled_fields != 0
6515 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6516 && DECL_NAME (constructor_unfilled_fields) == 0)
6517 constructor_unfilled_fields =
6518 TREE_CHAIN (constructor_unfilled_fields);
6519 }
6520 }
6521
6522 constructor_fields = TREE_CHAIN (constructor_fields);
6523 /* Skip any nameless bit fields at the beginning. */
6524 while (constructor_fields != 0
6525 && DECL_C_BIT_FIELD (constructor_fields)
6526 && DECL_NAME (constructor_fields) == 0)
6527 constructor_fields = TREE_CHAIN (constructor_fields);
6528 }
6529 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6530 {
6531 tree fieldtype;
6532 enum tree_code fieldcode;
6533
6534 if (constructor_fields == 0)
6535 {
6536 pedwarn_init ("excess elements in union initializer");
6537 break;
6538 }
6539
6540 fieldtype = TREE_TYPE (constructor_fields);
6541 if (fieldtype != error_mark_node)
6542 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6543 fieldcode = TREE_CODE (fieldtype);
6544
6545 /* Warn that traditional C rejects initialization of unions.
6546 We skip the warning if the value is zero. This is done
6547 under the assumption that the zero initializer in user
6548 code appears conditioned on e.g. __STDC__ to avoid
6549 "missing initializer" warnings and relies on default
6550 initialization to zero in the traditional C case.
6551 We also skip the warning if the initializer is designated,
6552 again on the assumption that this must be conditional on
6553 __STDC__ anyway (and we've already complained about the
6554 member-designator already). */
6555 if (!in_system_header && !constructor_designated
6556 && !(value.value && (integer_zerop (value.value)
6557 || real_zerop (value.value))))
6558 warning (OPT_Wtraditional, "traditional C rejects initialization "
6559 "of unions");
6560
6561 /* Accept a string constant to initialize a subarray. */
6562 if (value.value != 0
6563 && fieldcode == ARRAY_TYPE
6564 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6565 && string_flag)
6566 value.value = orig_value;
6567 /* Otherwise, if we have come to a subaggregate,
6568 and we don't have an element of its type, push into it. */
6569 else if (value.value != 0
6570 && value.value != error_mark_node
6571 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6572 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6573 || fieldcode == UNION_TYPE))
6574 {
6575 push_init_level (1);
6576 continue;
6577 }
6578
6579 if (value.value)
6580 {
6581 push_member_name (constructor_fields);
6582 output_init_element (value.value, strict_string,
6583 fieldtype, constructor_fields, 1);
6584 RESTORE_SPELLING_DEPTH (constructor_depth);
6585 }
6586 else
6587 /* Do the bookkeeping for an element that was
6588 directly output as a constructor. */
6589 {
6590 constructor_bit_index = DECL_SIZE (constructor_fields);
6591 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6592 }
6593
6594 constructor_fields = 0;
6595 }
6596 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6597 {
6598 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6599 enum tree_code eltcode = TREE_CODE (elttype);
6600
6601 /* Accept a string constant to initialize a subarray. */
6602 if (value.value != 0
6603 && eltcode == ARRAY_TYPE
6604 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
6605 && string_flag)
6606 value.value = orig_value;
6607 /* Otherwise, if we have come to a subaggregate,
6608 and we don't have an element of its type, push into it. */
6609 else if (value.value != 0
6610 && value.value != error_mark_node
6611 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
6612 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6613 || eltcode == UNION_TYPE))
6614 {
6615 push_init_level (1);
6616 continue;
6617 }
6618
6619 if (constructor_max_index != 0
6620 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6621 || integer_all_onesp (constructor_max_index)))
6622 {
6623 pedwarn_init ("excess elements in array initializer");
6624 break;
6625 }
6626
6627 /* Now output the actual element. */
6628 if (value.value)
6629 {
6630 push_array_bounds (tree_low_cst (constructor_index, 1));
6631 output_init_element (value.value, strict_string,
6632 elttype, constructor_index, 1);
6633 RESTORE_SPELLING_DEPTH (constructor_depth);
6634 }
6635
6636 constructor_index
6637 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6638
6639 if (!value.value)
6640 /* If we are doing the bookkeeping for an element that was
6641 directly output as a constructor, we must update
6642 constructor_unfilled_index. */
6643 constructor_unfilled_index = constructor_index;
6644 }
6645 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6646 {
6647 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6648
6649 /* Do a basic check of initializer size. Note that vectors
6650 always have a fixed size derived from their type. */
6651 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6652 {
6653 pedwarn_init ("excess elements in vector initializer");
6654 break;
6655 }
6656
6657 /* Now output the actual element. */
6658 if (value.value)
6659 output_init_element (value.value, strict_string,
6660 elttype, constructor_index, 1);
6661
6662 constructor_index
6663 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6664
6665 if (!value.value)
6666 /* If we are doing the bookkeeping for an element that was
6667 directly output as a constructor, we must update
6668 constructor_unfilled_index. */
6669 constructor_unfilled_index = constructor_index;
6670 }
6671
6672 /* Handle the sole element allowed in a braced initializer
6673 for a scalar variable. */
6674 else if (constructor_type != error_mark_node
6675 && constructor_fields == 0)
6676 {
6677 pedwarn_init ("excess elements in scalar initializer");
6678 break;
6679 }
6680 else
6681 {
6682 if (value.value)
6683 output_init_element (value.value, strict_string,
6684 constructor_type, NULL_TREE, 1);
6685 constructor_fields = 0;
6686 }
6687
6688 /* Handle range initializers either at this level or anywhere higher
6689 in the designator stack. */
6690 if (constructor_range_stack)
6691 {
6692 struct constructor_range_stack *p, *range_stack;
6693 int finish = 0;
6694
6695 range_stack = constructor_range_stack;
6696 constructor_range_stack = 0;
6697 while (constructor_stack != range_stack->stack)
6698 {
6699 gcc_assert (constructor_stack->implicit);
6700 process_init_element (pop_init_level (1));
6701 }
6702 for (p = range_stack;
6703 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6704 p = p->prev)
6705 {
6706 gcc_assert (constructor_stack->implicit);
6707 process_init_element (pop_init_level (1));
6708 }
6709
6710 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6711 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6712 finish = 1;
6713
6714 while (1)
6715 {
6716 constructor_index = p->index;
6717 constructor_fields = p->fields;
6718 if (finish && p->range_end && p->index == p->range_start)
6719 {
6720 finish = 0;
6721 p->prev = 0;
6722 }
6723 p = p->next;
6724 if (!p)
6725 break;
6726 push_init_level (2);
6727 p->stack = constructor_stack;
6728 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6729 p->index = p->range_start;
6730 }
6731
6732 if (!finish)
6733 constructor_range_stack = range_stack;
6734 continue;
6735 }
6736
6737 break;
6738 }
6739
6740 constructor_range_stack = 0;
6741 }
6742 \f
6743 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
6744 (guaranteed to be 'volatile' or null) and ARGS (represented using
6745 an ASM_EXPR node). */
6746 tree
6747 build_asm_stmt (tree cv_qualifier, tree args)
6748 {
6749 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6750 ASM_VOLATILE_P (args) = 1;
6751 return add_stmt (args);
6752 }
6753
6754 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6755 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6756 SIMPLE indicates whether there was anything at all after the
6757 string in the asm expression -- asm("blah") and asm("blah" : )
6758 are subtly different. We use a ASM_EXPR node to represent this. */
6759 tree
6760 build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6761 bool simple)
6762 {
6763 tree tail;
6764 tree args;
6765 int i;
6766 const char *constraint;
6767 const char **oconstraints;
6768 bool allows_mem, allows_reg, is_inout;
6769 int ninputs, noutputs;
6770
6771 ninputs = list_length (inputs);
6772 noutputs = list_length (outputs);
6773 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
6774
6775 string = resolve_asm_operand_names (string, outputs, inputs);
6776
6777 /* Remove output conversions that change the type but not the mode. */
6778 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6779 {
6780 tree output = TREE_VALUE (tail);
6781
6782 /* ??? Really, this should not be here. Users should be using a
6783 proper lvalue, dammit. But there's a long history of using casts
6784 in the output operands. In cases like longlong.h, this becomes a
6785 primitive form of typechecking -- if the cast can be removed, then
6786 the output operand had a type of the proper width; otherwise we'll
6787 get an error. Gross, but ... */
6788 STRIP_NOPS (output);
6789
6790 if (!lvalue_or_else (output, lv_asm))
6791 output = error_mark_node;
6792
6793 if (output != error_mark_node
6794 && (TREE_READONLY (output)
6795 || TYPE_READONLY (TREE_TYPE (output))
6796 || ((TREE_CODE (TREE_TYPE (output)) == RECORD_TYPE
6797 || TREE_CODE (TREE_TYPE (output)) == UNION_TYPE)
6798 && C_TYPE_FIELDS_READONLY (TREE_TYPE (output)))))
6799 readonly_error (output, lv_asm);
6800
6801 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6802 oconstraints[i] = constraint;
6803
6804 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
6805 &allows_mem, &allows_reg, &is_inout))
6806 {
6807 /* If the operand is going to end up in memory,
6808 mark it addressable. */
6809 if (!allows_reg && !c_mark_addressable (output))
6810 output = error_mark_node;
6811 }
6812 else
6813 output = error_mark_node;
6814
6815 TREE_VALUE (tail) = output;
6816 }
6817
6818 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
6819 {
6820 tree input;
6821
6822 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6823 input = TREE_VALUE (tail);
6824
6825 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
6826 oconstraints, &allows_mem, &allows_reg))
6827 {
6828 /* If the operand is going to end up in memory,
6829 mark it addressable. */
6830 if (!allows_reg && allows_mem)
6831 {
6832 /* Strip the nops as we allow this case. FIXME, this really
6833 should be rejected or made deprecated. */
6834 STRIP_NOPS (input);
6835 if (!c_mark_addressable (input))
6836 input = error_mark_node;
6837 }
6838 }
6839 else
6840 input = error_mark_node;
6841
6842 TREE_VALUE (tail) = input;
6843 }
6844
6845 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers);
6846
6847 /* asm statements without outputs, including simple ones, are treated
6848 as volatile. */
6849 ASM_INPUT_P (args) = simple;
6850 ASM_VOLATILE_P (args) = (noutputs == 0);
6851
6852 return args;
6853 }
6854 \f
6855 /* Generate a goto statement to LABEL. */
6856
6857 tree
6858 c_finish_goto_label (tree label)
6859 {
6860 tree decl = lookup_label (label);
6861 if (!decl)
6862 return NULL_TREE;
6863
6864 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl))
6865 {
6866 error ("jump into statement expression");
6867 return NULL_TREE;
6868 }
6869
6870 if (C_DECL_UNJUMPABLE_VM (decl))
6871 {
6872 error ("jump into scope of identifier with variably modified type");
6873 return NULL_TREE;
6874 }
6875
6876 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl))
6877 {
6878 /* No jump from outside this statement expression context, so
6879 record that there is a jump from within this context. */
6880 struct c_label_list *nlist;
6881 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6882 nlist->next = label_context_stack_se->labels_used;
6883 nlist->label = decl;
6884 label_context_stack_se->labels_used = nlist;
6885 }
6886
6887 if (!C_DECL_UNDEFINABLE_VM (decl))
6888 {
6889 /* No jump from outside this context context of identifiers with
6890 variably modified type, so record that there is a jump from
6891 within this context. */
6892 struct c_label_list *nlist;
6893 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6894 nlist->next = label_context_stack_vm->labels_used;
6895 nlist->label = decl;
6896 label_context_stack_vm->labels_used = nlist;
6897 }
6898
6899 TREE_USED (decl) = 1;
6900 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl));
6901 }
6902
6903 /* Generate a computed goto statement to EXPR. */
6904
6905 tree
6906 c_finish_goto_ptr (tree expr)
6907 {
6908 if (pedantic)
6909 pedwarn ("ISO C forbids %<goto *expr;%>");
6910 expr = convert (ptr_type_node, expr);
6911 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr));
6912 }
6913
6914 /* Generate a C `return' statement. RETVAL is the expression for what
6915 to return, or a null pointer for `return;' with no value. */
6916
6917 tree
6918 c_finish_return (tree retval)
6919 {
6920 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)), ret_stmt;
6921 bool no_warning = false;
6922
6923 if (TREE_THIS_VOLATILE (current_function_decl))
6924 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6925
6926 if (!retval)
6927 {
6928 current_function_returns_null = 1;
6929 if ((warn_return_type || flag_isoc99)
6930 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6931 {
6932 pedwarn_c99 ("%<return%> with no value, in "
6933 "function returning non-void");
6934 no_warning = true;
6935 }
6936 }
6937 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6938 {
6939 current_function_returns_null = 1;
6940 if (TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6941 pedwarn ("%<return%> with a value, in function returning void");
6942 else if (pedantic)
6943 pedwarn ("ISO C forbids %<return%> with expression, in function returning void");
6944 }
6945 else
6946 {
6947 tree t = convert_for_assignment (valtype, retval, ic_return,
6948 NULL_TREE, NULL_TREE, 0);
6949 tree res = DECL_RESULT (current_function_decl);
6950 tree inner;
6951
6952 current_function_returns_value = 1;
6953 if (t == error_mark_node)
6954 return NULL_TREE;
6955
6956 inner = t = convert (TREE_TYPE (res), t);
6957
6958 /* Strip any conversions, additions, and subtractions, and see if
6959 we are returning the address of a local variable. Warn if so. */
6960 while (1)
6961 {
6962 switch (TREE_CODE (inner))
6963 {
6964 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6965 case PLUS_EXPR:
6966 inner = TREE_OPERAND (inner, 0);
6967 continue;
6968
6969 case MINUS_EXPR:
6970 /* If the second operand of the MINUS_EXPR has a pointer
6971 type (or is converted from it), this may be valid, so
6972 don't give a warning. */
6973 {
6974 tree op1 = TREE_OPERAND (inner, 1);
6975
6976 while (!POINTER_TYPE_P (TREE_TYPE (op1))
6977 && (TREE_CODE (op1) == NOP_EXPR
6978 || TREE_CODE (op1) == NON_LVALUE_EXPR
6979 || TREE_CODE (op1) == CONVERT_EXPR))
6980 op1 = TREE_OPERAND (op1, 0);
6981
6982 if (POINTER_TYPE_P (TREE_TYPE (op1)))
6983 break;
6984
6985 inner = TREE_OPERAND (inner, 0);
6986 continue;
6987 }
6988
6989 case ADDR_EXPR:
6990 inner = TREE_OPERAND (inner, 0);
6991
6992 while (REFERENCE_CLASS_P (inner)
6993 && TREE_CODE (inner) != INDIRECT_REF)
6994 inner = TREE_OPERAND (inner, 0);
6995
6996 if (DECL_P (inner)
6997 && !DECL_EXTERNAL (inner)
6998 && !TREE_STATIC (inner)
6999 && DECL_CONTEXT (inner) == current_function_decl)
7000 warning (0, "function returns address of local variable");
7001 break;
7002
7003 default:
7004 break;
7005 }
7006
7007 break;
7008 }
7009
7010 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
7011 }
7012
7013 ret_stmt = build_stmt (RETURN_EXPR, retval);
7014 TREE_NO_WARNING (ret_stmt) |= no_warning;
7015 return add_stmt (ret_stmt);
7016 }
7017 \f
7018 struct c_switch {
7019 /* The SWITCH_EXPR being built. */
7020 tree switch_expr;
7021
7022 /* The original type of the testing expression, i.e. before the
7023 default conversion is applied. */
7024 tree orig_type;
7025
7026 /* A splay-tree mapping the low element of a case range to the high
7027 element, or NULL_TREE if there is no high element. Used to
7028 determine whether or not a new case label duplicates an old case
7029 label. We need a tree, rather than simply a hash table, because
7030 of the GNU case range extension. */
7031 splay_tree cases;
7032
7033 /* Number of nested statement expressions within this switch
7034 statement; if nonzero, case and default labels may not
7035 appear. */
7036 unsigned int blocked_stmt_expr;
7037
7038 /* Scope of outermost declarations of identifiers with variably
7039 modified type within this switch statement; if nonzero, case and
7040 default labels may not appear. */
7041 unsigned int blocked_vm;
7042
7043 /* The next node on the stack. */
7044 struct c_switch *next;
7045 };
7046
7047 /* A stack of the currently active switch statements. The innermost
7048 switch statement is on the top of the stack. There is no need to
7049 mark the stack for garbage collection because it is only active
7050 during the processing of the body of a function, and we never
7051 collect at that point. */
7052
7053 struct c_switch *c_switch_stack;
7054
7055 /* Start a C switch statement, testing expression EXP. Return the new
7056 SWITCH_EXPR. */
7057
7058 tree
7059 c_start_case (tree exp)
7060 {
7061 tree orig_type = error_mark_node;
7062 struct c_switch *cs;
7063
7064 if (exp != error_mark_node)
7065 {
7066 orig_type = TREE_TYPE (exp);
7067
7068 if (!INTEGRAL_TYPE_P (orig_type))
7069 {
7070 if (orig_type != error_mark_node)
7071 {
7072 error ("switch quantity not an integer");
7073 orig_type = error_mark_node;
7074 }
7075 exp = integer_zero_node;
7076 }
7077 else
7078 {
7079 tree type = TYPE_MAIN_VARIANT (orig_type);
7080
7081 if (!in_system_header
7082 && (type == long_integer_type_node
7083 || type == long_unsigned_type_node))
7084 warning (OPT_Wtraditional, "%<long%> switch expression not "
7085 "converted to %<int%> in ISO C");
7086
7087 exp = default_conversion (exp);
7088 }
7089 }
7090
7091 /* Add this new SWITCH_EXPR to the stack. */
7092 cs = XNEW (struct c_switch);
7093 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE);
7094 cs->orig_type = orig_type;
7095 cs->cases = splay_tree_new (case_compare, NULL, NULL);
7096 cs->blocked_stmt_expr = 0;
7097 cs->blocked_vm = 0;
7098 cs->next = c_switch_stack;
7099 c_switch_stack = cs;
7100
7101 return add_stmt (cs->switch_expr);
7102 }
7103
7104 /* Process a case label. */
7105
7106 tree
7107 do_case (tree low_value, tree high_value)
7108 {
7109 tree label = NULL_TREE;
7110
7111 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr
7112 && !c_switch_stack->blocked_vm)
7113 {
7114 label = c_add_case_label (c_switch_stack->cases,
7115 SWITCH_COND (c_switch_stack->switch_expr),
7116 c_switch_stack->orig_type,
7117 low_value, high_value);
7118 if (label == error_mark_node)
7119 label = NULL_TREE;
7120 }
7121 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr)
7122 {
7123 if (low_value)
7124 error ("case label in statement expression not containing "
7125 "enclosing switch statement");
7126 else
7127 error ("%<default%> label in statement expression not containing "
7128 "enclosing switch statement");
7129 }
7130 else if (c_switch_stack && c_switch_stack->blocked_vm)
7131 {
7132 if (low_value)
7133 error ("case label in scope of identifier with variably modified "
7134 "type not containing enclosing switch statement");
7135 else
7136 error ("%<default%> label in scope of identifier with variably "
7137 "modified type not containing enclosing switch statement");
7138 }
7139 else if (low_value)
7140 error ("case label not within a switch statement");
7141 else
7142 error ("%<default%> label not within a switch statement");
7143
7144 return label;
7145 }
7146
7147 /* Finish the switch statement. */
7148
7149 void
7150 c_finish_case (tree body)
7151 {
7152 struct c_switch *cs = c_switch_stack;
7153 location_t switch_location;
7154
7155 SWITCH_BODY (cs->switch_expr) = body;
7156
7157 /* We must not be within a statement expression nested in the switch
7158 at this point; we might, however, be within the scope of an
7159 identifier with variably modified type nested in the switch. */
7160 gcc_assert (!cs->blocked_stmt_expr);
7161
7162 /* Emit warnings as needed. */
7163 if (EXPR_HAS_LOCATION (cs->switch_expr))
7164 switch_location = EXPR_LOCATION (cs->switch_expr);
7165 else
7166 switch_location = input_location;
7167 c_do_switch_warnings (cs->cases, switch_location,
7168 TREE_TYPE (cs->switch_expr),
7169 SWITCH_COND (cs->switch_expr));
7170
7171 /* Pop the stack. */
7172 c_switch_stack = cs->next;
7173 splay_tree_delete (cs->cases);
7174 XDELETE (cs);
7175 }
7176 \f
7177 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
7178 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
7179 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
7180 statement, and was not surrounded with parenthesis. */
7181
7182 void
7183 c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
7184 tree else_block, bool nested_if)
7185 {
7186 tree stmt;
7187
7188 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
7189 if (warn_parentheses && nested_if && else_block == NULL)
7190 {
7191 tree inner_if = then_block;
7192
7193 /* We know from the grammar productions that there is an IF nested
7194 within THEN_BLOCK. Due to labels and c99 conditional declarations,
7195 it might not be exactly THEN_BLOCK, but should be the last
7196 non-container statement within. */
7197 while (1)
7198 switch (TREE_CODE (inner_if))
7199 {
7200 case COND_EXPR:
7201 goto found;
7202 case BIND_EXPR:
7203 inner_if = BIND_EXPR_BODY (inner_if);
7204 break;
7205 case STATEMENT_LIST:
7206 inner_if = expr_last (then_block);
7207 break;
7208 case TRY_FINALLY_EXPR:
7209 case TRY_CATCH_EXPR:
7210 inner_if = TREE_OPERAND (inner_if, 0);
7211 break;
7212 default:
7213 gcc_unreachable ();
7214 }
7215 found:
7216
7217 if (COND_EXPR_ELSE (inner_if))
7218 warning (OPT_Wparentheses,
7219 "%Hsuggest explicit braces to avoid ambiguous %<else%>",
7220 &if_locus);
7221 }
7222
7223 empty_body_warning (then_block, else_block);
7224
7225 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block);
7226 SET_EXPR_LOCATION (stmt, if_locus);
7227 add_stmt (stmt);
7228 }
7229
7230 /* Emit a general-purpose loop construct. START_LOCUS is the location of
7231 the beginning of the loop. COND is the loop condition. COND_IS_FIRST
7232 is false for DO loops. INCR is the FOR increment expression. BODY is
7233 the statement controlled by the loop. BLAB is the break label. CLAB is
7234 the continue label. Everything is allowed to be NULL. */
7235
7236 void
7237 c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
7238 tree blab, tree clab, bool cond_is_first)
7239 {
7240 tree entry = NULL, exit = NULL, t;
7241
7242 /* If the condition is zero don't generate a loop construct. */
7243 if (cond && integer_zerop (cond))
7244 {
7245 if (cond_is_first)
7246 {
7247 t = build_and_jump (&blab);
7248 SET_EXPR_LOCATION (t, start_locus);
7249 add_stmt (t);
7250 }
7251 }
7252 else
7253 {
7254 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
7255
7256 /* If we have an exit condition, then we build an IF with gotos either
7257 out of the loop, or to the top of it. If there's no exit condition,
7258 then we just build a jump back to the top. */
7259 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
7260
7261 if (cond && !integer_nonzerop (cond))
7262 {
7263 /* Canonicalize the loop condition to the end. This means
7264 generating a branch to the loop condition. Reuse the
7265 continue label, if possible. */
7266 if (cond_is_first)
7267 {
7268 if (incr || !clab)
7269 {
7270 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
7271 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
7272 }
7273 else
7274 t = build1 (GOTO_EXPR, void_type_node, clab);
7275 SET_EXPR_LOCATION (t, start_locus);
7276 add_stmt (t);
7277 }
7278
7279 t = build_and_jump (&blab);
7280 exit = fold_build3 (COND_EXPR, void_type_node, cond, exit, t);
7281 if (cond_is_first)
7282 SET_EXPR_LOCATION (exit, start_locus);
7283 else
7284 SET_EXPR_LOCATION (exit, input_location);
7285 }
7286
7287 add_stmt (top);
7288 }
7289
7290 if (body)
7291 add_stmt (body);
7292 if (clab)
7293 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
7294 if (incr)
7295 add_stmt (incr);
7296 if (entry)
7297 add_stmt (entry);
7298 if (exit)
7299 add_stmt (exit);
7300 if (blab)
7301 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
7302 }
7303
7304 tree
7305 c_finish_bc_stmt (tree *label_p, bool is_break)
7306 {
7307 bool skip;
7308 tree label = *label_p;
7309
7310 /* In switch statements break is sometimes stylistically used after
7311 a return statement. This can lead to spurious warnings about
7312 control reaching the end of a non-void function when it is
7313 inlined. Note that we are calling block_may_fallthru with
7314 language specific tree nodes; this works because
7315 block_may_fallthru returns true when given something it does not
7316 understand. */
7317 skip = !block_may_fallthru (cur_stmt_list);
7318
7319 if (!label)
7320 {
7321 if (!skip)
7322 *label_p = label = create_artificial_label ();
7323 }
7324 else if (TREE_CODE (label) == LABEL_DECL)
7325 ;
7326 else switch (TREE_INT_CST_LOW (label))
7327 {
7328 case 0:
7329 if (is_break)
7330 error ("break statement not within loop or switch");
7331 else
7332 error ("continue statement not within a loop");
7333 return NULL_TREE;
7334
7335 case 1:
7336 gcc_assert (is_break);
7337 error ("break statement used with OpenMP for loop");
7338 return NULL_TREE;
7339
7340 default:
7341 gcc_unreachable ();
7342 }
7343
7344 if (skip)
7345 return NULL_TREE;
7346
7347 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
7348 }
7349
7350 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
7351
7352 static void
7353 emit_side_effect_warnings (tree expr)
7354 {
7355 if (expr == error_mark_node)
7356 ;
7357 else if (!TREE_SIDE_EFFECTS (expr))
7358 {
7359 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
7360 warning (OPT_Wunused_value, "%Hstatement with no effect",
7361 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location);
7362 }
7363 else
7364 warn_if_unused_value (expr, input_location);
7365 }
7366
7367 /* Process an expression as if it were a complete statement. Emit
7368 diagnostics, but do not call ADD_STMT. */
7369
7370 tree
7371 c_process_expr_stmt (tree expr)
7372 {
7373 if (!expr)
7374 return NULL_TREE;
7375
7376 if (warn_sequence_point)
7377 verify_sequence_points (expr);
7378
7379 if (TREE_TYPE (expr) != error_mark_node
7380 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
7381 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
7382 error ("expression statement has incomplete type");
7383
7384 /* If we're not processing a statement expression, warn about unused values.
7385 Warnings for statement expressions will be emitted later, once we figure
7386 out which is the result. */
7387 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7388 && warn_unused_value)
7389 emit_side_effect_warnings (expr);
7390
7391 /* If the expression is not of a type to which we cannot assign a line
7392 number, wrap the thing in a no-op NOP_EXPR. */
7393 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
7394 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
7395
7396 if (CAN_HAVE_LOCATION_P (expr))
7397 SET_EXPR_LOCATION (expr, input_location);
7398
7399 return expr;
7400 }
7401
7402 /* Emit an expression as a statement. */
7403
7404 tree
7405 c_finish_expr_stmt (tree expr)
7406 {
7407 if (expr)
7408 return add_stmt (c_process_expr_stmt (expr));
7409 else
7410 return NULL;
7411 }
7412
7413 /* Do the opposite and emit a statement as an expression. To begin,
7414 create a new binding level and return it. */
7415
7416 tree
7417 c_begin_stmt_expr (void)
7418 {
7419 tree ret;
7420 struct c_label_context_se *nstack;
7421 struct c_label_list *glist;
7422
7423 /* We must force a BLOCK for this level so that, if it is not expanded
7424 later, there is a way to turn off the entire subtree of blocks that
7425 are contained in it. */
7426 keep_next_level ();
7427 ret = c_begin_compound_stmt (true);
7428 if (c_switch_stack)
7429 {
7430 c_switch_stack->blocked_stmt_expr++;
7431 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7432 }
7433 for (glist = label_context_stack_se->labels_used;
7434 glist != NULL;
7435 glist = glist->next)
7436 {
7437 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1;
7438 }
7439 nstack = XOBNEW (&parser_obstack, struct c_label_context_se);
7440 nstack->labels_def = NULL;
7441 nstack->labels_used = NULL;
7442 nstack->next = label_context_stack_se;
7443 label_context_stack_se = nstack;
7444
7445 /* Mark the current statement list as belonging to a statement list. */
7446 STATEMENT_LIST_STMT_EXPR (ret) = 1;
7447
7448 return ret;
7449 }
7450
7451 tree
7452 c_finish_stmt_expr (tree body)
7453 {
7454 tree last, type, tmp, val;
7455 tree *last_p;
7456 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7457
7458 body = c_end_compound_stmt (body, true);
7459 if (c_switch_stack)
7460 {
7461 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7462 c_switch_stack->blocked_stmt_expr--;
7463 }
7464 /* It is no longer possible to jump to labels defined within this
7465 statement expression. */
7466 for (dlist = label_context_stack_se->labels_def;
7467 dlist != NULL;
7468 dlist = dlist->next)
7469 {
7470 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1;
7471 }
7472 /* It is again possible to define labels with a goto just outside
7473 this statement expression. */
7474 for (glist = label_context_stack_se->next->labels_used;
7475 glist != NULL;
7476 glist = glist->next)
7477 {
7478 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0;
7479 glist_prev = glist;
7480 }
7481 if (glist_prev != NULL)
7482 glist_prev->next = label_context_stack_se->labels_used;
7483 else
7484 label_context_stack_se->next->labels_used
7485 = label_context_stack_se->labels_used;
7486 label_context_stack_se = label_context_stack_se->next;
7487
7488 /* Locate the last statement in BODY. See c_end_compound_stmt
7489 about always returning a BIND_EXPR. */
7490 last_p = &BIND_EXPR_BODY (body);
7491 last = BIND_EXPR_BODY (body);
7492
7493 continue_searching:
7494 if (TREE_CODE (last) == STATEMENT_LIST)
7495 {
7496 tree_stmt_iterator i;
7497
7498 /* This can happen with degenerate cases like ({ }). No value. */
7499 if (!TREE_SIDE_EFFECTS (last))
7500 return body;
7501
7502 /* If we're supposed to generate side effects warnings, process
7503 all of the statements except the last. */
7504 if (warn_unused_value)
7505 {
7506 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
7507 emit_side_effect_warnings (tsi_stmt (i));
7508 }
7509 else
7510 i = tsi_last (last);
7511 last_p = tsi_stmt_ptr (i);
7512 last = *last_p;
7513 }
7514
7515 /* If the end of the list is exception related, then the list was split
7516 by a call to push_cleanup. Continue searching. */
7517 if (TREE_CODE (last) == TRY_FINALLY_EXPR
7518 || TREE_CODE (last) == TRY_CATCH_EXPR)
7519 {
7520 last_p = &TREE_OPERAND (last, 0);
7521 last = *last_p;
7522 goto continue_searching;
7523 }
7524
7525 /* In the case that the BIND_EXPR is not necessary, return the
7526 expression out from inside it. */
7527 if (last == error_mark_node
7528 || (last == BIND_EXPR_BODY (body)
7529 && BIND_EXPR_VARS (body) == NULL))
7530 {
7531 /* Do not warn if the return value of a statement expression is
7532 unused. */
7533 if (CAN_HAVE_LOCATION_P (last))
7534 TREE_NO_WARNING (last) = 1;
7535 return last;
7536 }
7537
7538 /* Extract the type of said expression. */
7539 type = TREE_TYPE (last);
7540
7541 /* If we're not returning a value at all, then the BIND_EXPR that
7542 we already have is a fine expression to return. */
7543 if (!type || VOID_TYPE_P (type))
7544 return body;
7545
7546 /* Now that we've located the expression containing the value, it seems
7547 silly to make voidify_wrapper_expr repeat the process. Create a
7548 temporary of the appropriate type and stick it in a TARGET_EXPR. */
7549 tmp = create_tmp_var_raw (type, NULL);
7550
7551 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
7552 tree_expr_nonnegative_p giving up immediately. */
7553 val = last;
7554 if (TREE_CODE (val) == NOP_EXPR
7555 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
7556 val = TREE_OPERAND (val, 0);
7557
7558 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
7559 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last));
7560
7561 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
7562 }
7563
7564 /* Begin the scope of an identifier of variably modified type, scope
7565 number SCOPE. Jumping from outside this scope to inside it is not
7566 permitted. */
7567
7568 void
7569 c_begin_vm_scope (unsigned int scope)
7570 {
7571 struct c_label_context_vm *nstack;
7572 struct c_label_list *glist;
7573
7574 gcc_assert (scope > 0);
7575
7576 /* At file_scope, we don't have to do any processing. */
7577 if (label_context_stack_vm == NULL)
7578 return;
7579
7580 if (c_switch_stack && !c_switch_stack->blocked_vm)
7581 c_switch_stack->blocked_vm = scope;
7582 for (glist = label_context_stack_vm->labels_used;
7583 glist != NULL;
7584 glist = glist->next)
7585 {
7586 C_DECL_UNDEFINABLE_VM (glist->label) = 1;
7587 }
7588 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm);
7589 nstack->labels_def = NULL;
7590 nstack->labels_used = NULL;
7591 nstack->scope = scope;
7592 nstack->next = label_context_stack_vm;
7593 label_context_stack_vm = nstack;
7594 }
7595
7596 /* End a scope which may contain identifiers of variably modified
7597 type, scope number SCOPE. */
7598
7599 void
7600 c_end_vm_scope (unsigned int scope)
7601 {
7602 if (label_context_stack_vm == NULL)
7603 return;
7604 if (c_switch_stack && c_switch_stack->blocked_vm == scope)
7605 c_switch_stack->blocked_vm = 0;
7606 /* We may have a number of nested scopes of identifiers with
7607 variably modified type, all at this depth. Pop each in turn. */
7608 while (label_context_stack_vm->scope == scope)
7609 {
7610 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7611
7612 /* It is no longer possible to jump to labels defined within this
7613 scope. */
7614 for (dlist = label_context_stack_vm->labels_def;
7615 dlist != NULL;
7616 dlist = dlist->next)
7617 {
7618 C_DECL_UNJUMPABLE_VM (dlist->label) = 1;
7619 }
7620 /* It is again possible to define labels with a goto just outside
7621 this scope. */
7622 for (glist = label_context_stack_vm->next->labels_used;
7623 glist != NULL;
7624 glist = glist->next)
7625 {
7626 C_DECL_UNDEFINABLE_VM (glist->label) = 0;
7627 glist_prev = glist;
7628 }
7629 if (glist_prev != NULL)
7630 glist_prev->next = label_context_stack_vm->labels_used;
7631 else
7632 label_context_stack_vm->next->labels_used
7633 = label_context_stack_vm->labels_used;
7634 label_context_stack_vm = label_context_stack_vm->next;
7635 }
7636 }
7637 \f
7638 /* Begin and end compound statements. This is as simple as pushing
7639 and popping new statement lists from the tree. */
7640
7641 tree
7642 c_begin_compound_stmt (bool do_scope)
7643 {
7644 tree stmt = push_stmt_list ();
7645 if (do_scope)
7646 push_scope ();
7647 return stmt;
7648 }
7649
7650 tree
7651 c_end_compound_stmt (tree stmt, bool do_scope)
7652 {
7653 tree block = NULL;
7654
7655 if (do_scope)
7656 {
7657 if (c_dialect_objc ())
7658 objc_clear_super_receiver ();
7659 block = pop_scope ();
7660 }
7661
7662 stmt = pop_stmt_list (stmt);
7663 stmt = c_build_bind_expr (block, stmt);
7664
7665 /* If this compound statement is nested immediately inside a statement
7666 expression, then force a BIND_EXPR to be created. Otherwise we'll
7667 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
7668 STATEMENT_LISTs merge, and thus we can lose track of what statement
7669 was really last. */
7670 if (cur_stmt_list
7671 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7672 && TREE_CODE (stmt) != BIND_EXPR)
7673 {
7674 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
7675 TREE_SIDE_EFFECTS (stmt) = 1;
7676 }
7677
7678 return stmt;
7679 }
7680
7681 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
7682 when the current scope is exited. EH_ONLY is true when this is not
7683 meant to apply to normal control flow transfer. */
7684
7685 void
7686 push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only)
7687 {
7688 enum tree_code code;
7689 tree stmt, list;
7690 bool stmt_expr;
7691
7692 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
7693 stmt = build_stmt (code, NULL, cleanup);
7694 add_stmt (stmt);
7695 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
7696 list = push_stmt_list ();
7697 TREE_OPERAND (stmt, 0) = list;
7698 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
7699 }
7700 \f
7701 /* Build a binary-operation expression without default conversions.
7702 CODE is the kind of expression to build.
7703 This function differs from `build' in several ways:
7704 the data type of the result is computed and recorded in it,
7705 warnings are generated if arg data types are invalid,
7706 special handling for addition and subtraction of pointers is known,
7707 and some optimization is done (operations on narrow ints
7708 are done in the narrower type when that gives the same result).
7709 Constant folding is also done before the result is returned.
7710
7711 Note that the operands will never have enumeral types, or function
7712 or array types, because either they will have the default conversions
7713 performed or they have both just been converted to some other type in which
7714 the arithmetic is to be done. */
7715
7716 tree
7717 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
7718 int convert_p)
7719 {
7720 tree type0, type1;
7721 enum tree_code code0, code1;
7722 tree op0, op1;
7723 const char *invalid_op_diag;
7724
7725 /* Expression code to give to the expression when it is built.
7726 Normally this is CODE, which is what the caller asked for,
7727 but in some special cases we change it. */
7728 enum tree_code resultcode = code;
7729
7730 /* Data type in which the computation is to be performed.
7731 In the simplest cases this is the common type of the arguments. */
7732 tree result_type = NULL;
7733
7734 /* Nonzero means operands have already been type-converted
7735 in whatever way is necessary.
7736 Zero means they need to be converted to RESULT_TYPE. */
7737 int converted = 0;
7738
7739 /* Nonzero means create the expression with this type, rather than
7740 RESULT_TYPE. */
7741 tree build_type = 0;
7742
7743 /* Nonzero means after finally constructing the expression
7744 convert it to this type. */
7745 tree final_type = 0;
7746
7747 /* Nonzero if this is an operation like MIN or MAX which can
7748 safely be computed in short if both args are promoted shorts.
7749 Also implies COMMON.
7750 -1 indicates a bitwise operation; this makes a difference
7751 in the exact conditions for when it is safe to do the operation
7752 in a narrower mode. */
7753 int shorten = 0;
7754
7755 /* Nonzero if this is a comparison operation;
7756 if both args are promoted shorts, compare the original shorts.
7757 Also implies COMMON. */
7758 int short_compare = 0;
7759
7760 /* Nonzero if this is a right-shift operation, which can be computed on the
7761 original short and then promoted if the operand is a promoted short. */
7762 int short_shift = 0;
7763
7764 /* Nonzero means set RESULT_TYPE to the common type of the args. */
7765 int common = 0;
7766
7767 /* True means types are compatible as far as ObjC is concerned. */
7768 bool objc_ok;
7769
7770 if (convert_p)
7771 {
7772 op0 = default_conversion (orig_op0);
7773 op1 = default_conversion (orig_op1);
7774 }
7775 else
7776 {
7777 op0 = orig_op0;
7778 op1 = orig_op1;
7779 }
7780
7781 type0 = TREE_TYPE (op0);
7782 type1 = TREE_TYPE (op1);
7783
7784 /* The expression codes of the data types of the arguments tell us
7785 whether the arguments are integers, floating, pointers, etc. */
7786 code0 = TREE_CODE (type0);
7787 code1 = TREE_CODE (type1);
7788
7789 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
7790 STRIP_TYPE_NOPS (op0);
7791 STRIP_TYPE_NOPS (op1);
7792
7793 /* If an error was already reported for one of the arguments,
7794 avoid reporting another error. */
7795
7796 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7797 return error_mark_node;
7798
7799 if ((invalid_op_diag
7800 = targetm.invalid_binary_op (code, type0, type1)))
7801 {
7802 error (invalid_op_diag);
7803 return error_mark_node;
7804 }
7805
7806 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE);
7807
7808 switch (code)
7809 {
7810 case PLUS_EXPR:
7811 /* Handle the pointer + int case. */
7812 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7813 return pointer_int_sum (PLUS_EXPR, op0, op1);
7814 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
7815 return pointer_int_sum (PLUS_EXPR, op1, op0);
7816 else
7817 common = 1;
7818 break;
7819
7820 case MINUS_EXPR:
7821 /* Subtraction of two similar pointers.
7822 We must subtract them as integers, then divide by object size. */
7823 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
7824 && comp_target_types (type0, type1))
7825 return pointer_diff (op0, op1);
7826 /* Handle pointer minus int. Just like pointer plus int. */
7827 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7828 return pointer_int_sum (MINUS_EXPR, op0, op1);
7829 else
7830 common = 1;
7831 break;
7832
7833 case MULT_EXPR:
7834 common = 1;
7835 break;
7836
7837 case TRUNC_DIV_EXPR:
7838 case CEIL_DIV_EXPR:
7839 case FLOOR_DIV_EXPR:
7840 case ROUND_DIV_EXPR:
7841 case EXACT_DIV_EXPR:
7842 /* Floating point division by zero is a legitimate way to obtain
7843 infinities and NaNs. */
7844 if (skip_evaluation == 0 && integer_zerop (op1))
7845 warning (OPT_Wdiv_by_zero, "division by zero");
7846
7847 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7848 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7849 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7850 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
7851 {
7852 enum tree_code tcode0 = code0, tcode1 = code1;
7853
7854 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7855 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
7856 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
7857 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
7858
7859 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
7860 resultcode = RDIV_EXPR;
7861 else
7862 /* Although it would be tempting to shorten always here, that
7863 loses on some targets, since the modulo instruction is
7864 undefined if the quotient can't be represented in the
7865 computation mode. We shorten only if unsigned or if
7866 dividing by something we know != -1. */
7867 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7868 || (TREE_CODE (op1) == INTEGER_CST
7869 && !integer_all_onesp (op1)));
7870 common = 1;
7871 }
7872 break;
7873
7874 case BIT_AND_EXPR:
7875 case BIT_IOR_EXPR:
7876 case BIT_XOR_EXPR:
7877 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7878 shorten = -1;
7879 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
7880 common = 1;
7881 break;
7882
7883 case TRUNC_MOD_EXPR:
7884 case FLOOR_MOD_EXPR:
7885 if (skip_evaluation == 0 && integer_zerop (op1))
7886 warning (OPT_Wdiv_by_zero, "division by zero");
7887
7888 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7889 {
7890 /* Although it would be tempting to shorten always here, that loses
7891 on some targets, since the modulo instruction is undefined if the
7892 quotient can't be represented in the computation mode. We shorten
7893 only if unsigned or if dividing by something we know != -1. */
7894 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7895 || (TREE_CODE (op1) == INTEGER_CST
7896 && !integer_all_onesp (op1)));
7897 common = 1;
7898 }
7899 break;
7900
7901 case TRUTH_ANDIF_EXPR:
7902 case TRUTH_ORIF_EXPR:
7903 case TRUTH_AND_EXPR:
7904 case TRUTH_OR_EXPR:
7905 case TRUTH_XOR_EXPR:
7906 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
7907 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
7908 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
7909 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
7910 {
7911 /* Result of these operations is always an int,
7912 but that does not mean the operands should be
7913 converted to ints! */
7914 result_type = integer_type_node;
7915 op0 = c_common_truthvalue_conversion (op0);
7916 op1 = c_common_truthvalue_conversion (op1);
7917 converted = 1;
7918 }
7919 break;
7920
7921 /* Shift operations: result has same type as first operand;
7922 always convert second operand to int.
7923 Also set SHORT_SHIFT if shifting rightward. */
7924
7925 case RSHIFT_EXPR:
7926 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7927 {
7928 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7929 {
7930 if (tree_int_cst_sgn (op1) < 0)
7931 warning (0, "right shift count is negative");
7932 else
7933 {
7934 if (!integer_zerop (op1))
7935 short_shift = 1;
7936
7937 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7938 warning (0, "right shift count >= width of type");
7939 }
7940 }
7941
7942 /* Use the type of the value to be shifted. */
7943 result_type = type0;
7944 /* Convert the shift-count to an integer, regardless of size
7945 of value being shifted. */
7946 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7947 op1 = convert (integer_type_node, op1);
7948 /* Avoid converting op1 to result_type later. */
7949 converted = 1;
7950 }
7951 break;
7952
7953 case LSHIFT_EXPR:
7954 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7955 {
7956 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7957 {
7958 if (tree_int_cst_sgn (op1) < 0)
7959 warning (0, "left shift count is negative");
7960
7961 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7962 warning (0, "left shift count >= width of type");
7963 }
7964
7965 /* Use the type of the value to be shifted. */
7966 result_type = type0;
7967 /* Convert the shift-count to an integer, regardless of size
7968 of value being shifted. */
7969 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7970 op1 = convert (integer_type_node, op1);
7971 /* Avoid converting op1 to result_type later. */
7972 converted = 1;
7973 }
7974 break;
7975
7976 case EQ_EXPR:
7977 case NE_EXPR:
7978 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
7979 warning (OPT_Wfloat_equal,
7980 "comparing floating point with == or != is unsafe");
7981 /* Result of comparison is always int,
7982 but don't convert the args to int! */
7983 build_type = integer_type_node;
7984 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7985 || code0 == COMPLEX_TYPE)
7986 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7987 || code1 == COMPLEX_TYPE))
7988 short_compare = 1;
7989 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
7990 {
7991 tree tt0 = TREE_TYPE (type0);
7992 tree tt1 = TREE_TYPE (type1);
7993 /* Anything compares with void *. void * compares with anything.
7994 Otherwise, the targets must be compatible
7995 and both must be object or both incomplete. */
7996 if (comp_target_types (type0, type1))
7997 result_type = common_pointer_type (type0, type1);
7998 else if (VOID_TYPE_P (tt0))
7999 {
8000 /* op0 != orig_op0 detects the case of something
8001 whose value is 0 but which isn't a valid null ptr const. */
8002 if (pedantic && !null_pointer_constant_p (orig_op0)
8003 && TREE_CODE (tt1) == FUNCTION_TYPE)
8004 pedwarn ("ISO C forbids comparison of %<void *%>"
8005 " with function pointer");
8006 }
8007 else if (VOID_TYPE_P (tt1))
8008 {
8009 if (pedantic && !null_pointer_constant_p (orig_op1)
8010 && TREE_CODE (tt0) == FUNCTION_TYPE)
8011 pedwarn ("ISO C forbids comparison of %<void *%>"
8012 " with function pointer");
8013 }
8014 else
8015 /* Avoid warning about the volatile ObjC EH puts on decls. */
8016 if (!objc_ok)
8017 pedwarn ("comparison of distinct pointer types lacks a cast");
8018
8019 if (result_type == NULL_TREE)
8020 result_type = ptr_type_node;
8021 }
8022 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
8023 {
8024 if (TREE_CODE (op0) == ADDR_EXPR
8025 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
8026 warning (OPT_Waddress, "the address of %qD will never be NULL",
8027 TREE_OPERAND (op0, 0));
8028 result_type = type0;
8029 }
8030 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
8031 {
8032 if (TREE_CODE (op1) == ADDR_EXPR
8033 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
8034 warning (OPT_Waddress, "the address of %qD will never be NULL",
8035 TREE_OPERAND (op1, 0));
8036 result_type = type1;
8037 }
8038 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
8039 {
8040 result_type = type0;
8041 pedwarn ("comparison between pointer and integer");
8042 }
8043 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
8044 {
8045 result_type = type1;
8046 pedwarn ("comparison between pointer and integer");
8047 }
8048 break;
8049
8050 case LE_EXPR:
8051 case GE_EXPR:
8052 case LT_EXPR:
8053 case GT_EXPR:
8054 build_type = integer_type_node;
8055 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
8056 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
8057 short_compare = 1;
8058 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
8059 {
8060 if (comp_target_types (type0, type1))
8061 {
8062 result_type = common_pointer_type (type0, type1);
8063 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
8064 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
8065 pedwarn ("comparison of complete and incomplete pointers");
8066 else if (pedantic
8067 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
8068 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
8069 }
8070 else
8071 {
8072 result_type = ptr_type_node;
8073 pedwarn ("comparison of distinct pointer types lacks a cast");
8074 }
8075 }
8076 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
8077 {
8078 result_type = type0;
8079 if (pedantic || extra_warnings)
8080 pedwarn ("ordered comparison of pointer with integer zero");
8081 }
8082 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
8083 {
8084 result_type = type1;
8085 if (pedantic)
8086 pedwarn ("ordered comparison of pointer with integer zero");
8087 }
8088 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
8089 {
8090 result_type = type0;
8091 pedwarn ("comparison between pointer and integer");
8092 }
8093 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
8094 {
8095 result_type = type1;
8096 pedwarn ("comparison between pointer and integer");
8097 }
8098 break;
8099
8100 default:
8101 gcc_unreachable ();
8102 }
8103
8104 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
8105 return error_mark_node;
8106
8107 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
8108 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
8109 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
8110 TREE_TYPE (type1))))
8111 {
8112 binary_op_error (code);
8113 return error_mark_node;
8114 }
8115
8116 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
8117 || code0 == VECTOR_TYPE)
8118 &&
8119 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
8120 || code1 == VECTOR_TYPE))
8121 {
8122 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
8123
8124 if (shorten || common || short_compare)
8125 result_type = c_common_type (type0, type1);
8126
8127 /* For certain operations (which identify themselves by shorten != 0)
8128 if both args were extended from the same smaller type,
8129 do the arithmetic in that type and then extend.
8130
8131 shorten !=0 and !=1 indicates a bitwise operation.
8132 For them, this optimization is safe only if
8133 both args are zero-extended or both are sign-extended.
8134 Otherwise, we might change the result.
8135 Eg, (short)-1 | (unsigned short)-1 is (int)-1
8136 but calculated in (unsigned short) it would be (unsigned short)-1. */
8137
8138 if (shorten && none_complex)
8139 {
8140 int unsigned0, unsigned1;
8141 tree arg0, arg1;
8142 int uns;
8143 tree type;
8144
8145 /* Cast OP0 and OP1 to RESULT_TYPE. Doing so prevents
8146 excessive narrowing when we call get_narrower below. For
8147 example, suppose that OP0 is of unsigned int extended
8148 from signed char and that RESULT_TYPE is long long int.
8149 If we explicitly cast OP0 to RESULT_TYPE, OP0 would look
8150 like
8151
8152 (long long int) (unsigned int) signed_char
8153
8154 which get_narrower would narrow down to
8155
8156 (unsigned int) signed char
8157
8158 If we do not cast OP0 first, get_narrower would return
8159 signed_char, which is inconsistent with the case of the
8160 explicit cast. */
8161 op0 = convert (result_type, op0);
8162 op1 = convert (result_type, op1);
8163
8164 arg0 = get_narrower (op0, &unsigned0);
8165 arg1 = get_narrower (op1, &unsigned1);
8166
8167 /* UNS is 1 if the operation to be done is an unsigned one. */
8168 uns = TYPE_UNSIGNED (result_type);
8169
8170 final_type = result_type;
8171
8172 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
8173 but it *requires* conversion to FINAL_TYPE. */
8174
8175 if ((TYPE_PRECISION (TREE_TYPE (op0))
8176 == TYPE_PRECISION (TREE_TYPE (arg0)))
8177 && TREE_TYPE (op0) != final_type)
8178 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
8179 if ((TYPE_PRECISION (TREE_TYPE (op1))
8180 == TYPE_PRECISION (TREE_TYPE (arg1)))
8181 && TREE_TYPE (op1) != final_type)
8182 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
8183
8184 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
8185
8186 /* For bitwise operations, signedness of nominal type
8187 does not matter. Consider only how operands were extended. */
8188 if (shorten == -1)
8189 uns = unsigned0;
8190
8191 /* Note that in all three cases below we refrain from optimizing
8192 an unsigned operation on sign-extended args.
8193 That would not be valid. */
8194
8195 /* Both args variable: if both extended in same way
8196 from same width, do it in that width.
8197 Do it unsigned if args were zero-extended. */
8198 if ((TYPE_PRECISION (TREE_TYPE (arg0))
8199 < TYPE_PRECISION (result_type))
8200 && (TYPE_PRECISION (TREE_TYPE (arg1))
8201 == TYPE_PRECISION (TREE_TYPE (arg0)))
8202 && unsigned0 == unsigned1
8203 && (unsigned0 || !uns))
8204 result_type
8205 = c_common_signed_or_unsigned_type
8206 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
8207 else if (TREE_CODE (arg0) == INTEGER_CST
8208 && (unsigned1 || !uns)
8209 && (TYPE_PRECISION (TREE_TYPE (arg1))
8210 < TYPE_PRECISION (result_type))
8211 && (type
8212 = c_common_signed_or_unsigned_type (unsigned1,
8213 TREE_TYPE (arg1)),
8214 int_fits_type_p (arg0, type)))
8215 result_type = type;
8216 else if (TREE_CODE (arg1) == INTEGER_CST
8217 && (unsigned0 || !uns)
8218 && (TYPE_PRECISION (TREE_TYPE (arg0))
8219 < TYPE_PRECISION (result_type))
8220 && (type
8221 = c_common_signed_or_unsigned_type (unsigned0,
8222 TREE_TYPE (arg0)),
8223 int_fits_type_p (arg1, type)))
8224 result_type = type;
8225 }
8226
8227 /* Shifts can be shortened if shifting right. */
8228
8229 if (short_shift)
8230 {
8231 int unsigned_arg;
8232 tree arg0 = get_narrower (op0, &unsigned_arg);
8233
8234 final_type = result_type;
8235
8236 if (arg0 == op0 && final_type == TREE_TYPE (op0))
8237 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
8238
8239 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
8240 /* We can shorten only if the shift count is less than the
8241 number of bits in the smaller type size. */
8242 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
8243 /* We cannot drop an unsigned shift after sign-extension. */
8244 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
8245 {
8246 /* Do an unsigned shift if the operand was zero-extended. */
8247 result_type
8248 = c_common_signed_or_unsigned_type (unsigned_arg,
8249 TREE_TYPE (arg0));
8250 /* Convert value-to-be-shifted to that type. */
8251 if (TREE_TYPE (op0) != result_type)
8252 op0 = convert (result_type, op0);
8253 converted = 1;
8254 }
8255 }
8256
8257 /* Comparison operations are shortened too but differently.
8258 They identify themselves by setting short_compare = 1. */
8259
8260 if (short_compare)
8261 {
8262 /* Don't write &op0, etc., because that would prevent op0
8263 from being kept in a register.
8264 Instead, make copies of the our local variables and
8265 pass the copies by reference, then copy them back afterward. */
8266 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
8267 enum tree_code xresultcode = resultcode;
8268 tree val
8269 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
8270
8271 if (val != 0)
8272 return val;
8273
8274 op0 = xop0, op1 = xop1;
8275 converted = 1;
8276 resultcode = xresultcode;
8277
8278 if (warn_sign_compare && skip_evaluation == 0)
8279 {
8280 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
8281 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
8282 int unsignedp0, unsignedp1;
8283 tree primop0 = get_narrower (op0, &unsignedp0);
8284 tree primop1 = get_narrower (op1, &unsignedp1);
8285
8286 xop0 = orig_op0;
8287 xop1 = orig_op1;
8288 STRIP_TYPE_NOPS (xop0);
8289 STRIP_TYPE_NOPS (xop1);
8290
8291 /* Give warnings for comparisons between signed and unsigned
8292 quantities that may fail.
8293
8294 Do the checking based on the original operand trees, so that
8295 casts will be considered, but default promotions won't be.
8296
8297 Do not warn if the comparison is being done in a signed type,
8298 since the signed type will only be chosen if it can represent
8299 all the values of the unsigned type. */
8300 if (!TYPE_UNSIGNED (result_type))
8301 /* OK */;
8302 /* Do not warn if both operands are the same signedness. */
8303 else if (op0_signed == op1_signed)
8304 /* OK */;
8305 else
8306 {
8307 tree sop, uop;
8308 bool ovf;
8309
8310 if (op0_signed)
8311 sop = xop0, uop = xop1;
8312 else
8313 sop = xop1, uop = xop0;
8314
8315 /* Do not warn if the signed quantity is an
8316 unsuffixed integer literal (or some static
8317 constant expression involving such literals or a
8318 conditional expression involving such literals)
8319 and it is non-negative. */
8320 if (tree_expr_nonnegative_warnv_p (sop, &ovf))
8321 /* OK */;
8322 /* Do not warn if the comparison is an equality operation,
8323 the unsigned quantity is an integral constant, and it
8324 would fit in the result if the result were signed. */
8325 else if (TREE_CODE (uop) == INTEGER_CST
8326 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
8327 && int_fits_type_p
8328 (uop, c_common_signed_type (result_type)))
8329 /* OK */;
8330 /* Do not warn if the unsigned quantity is an enumeration
8331 constant and its maximum value would fit in the result
8332 if the result were signed. */
8333 else if (TREE_CODE (uop) == INTEGER_CST
8334 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
8335 && int_fits_type_p
8336 (TYPE_MAX_VALUE (TREE_TYPE (uop)),
8337 c_common_signed_type (result_type)))
8338 /* OK */;
8339 else
8340 warning (0, "comparison between signed and unsigned");
8341 }
8342
8343 /* Warn if two unsigned values are being compared in a size
8344 larger than their original size, and one (and only one) is the
8345 result of a `~' operator. This comparison will always fail.
8346
8347 Also warn if one operand is a constant, and the constant
8348 does not have all bits set that are set in the ~ operand
8349 when it is extended. */
8350
8351 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
8352 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
8353 {
8354 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
8355 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
8356 &unsignedp0);
8357 else
8358 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
8359 &unsignedp1);
8360
8361 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
8362 {
8363 tree primop;
8364 HOST_WIDE_INT constant, mask;
8365 int unsignedp, bits;
8366
8367 if (host_integerp (primop0, 0))
8368 {
8369 primop = primop1;
8370 unsignedp = unsignedp1;
8371 constant = tree_low_cst (primop0, 0);
8372 }
8373 else
8374 {
8375 primop = primop0;
8376 unsignedp = unsignedp0;
8377 constant = tree_low_cst (primop1, 0);
8378 }
8379
8380 bits = TYPE_PRECISION (TREE_TYPE (primop));
8381 if (bits < TYPE_PRECISION (result_type)
8382 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
8383 {
8384 mask = (~(HOST_WIDE_INT) 0) << bits;
8385 if ((mask & constant) != mask)
8386 warning (0, "comparison of promoted ~unsigned with constant");
8387 }
8388 }
8389 else if (unsignedp0 && unsignedp1
8390 && (TYPE_PRECISION (TREE_TYPE (primop0))
8391 < TYPE_PRECISION (result_type))
8392 && (TYPE_PRECISION (TREE_TYPE (primop1))
8393 < TYPE_PRECISION (result_type)))
8394 warning (0, "comparison of promoted ~unsigned with unsigned");
8395 }
8396 }
8397 }
8398 }
8399
8400 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
8401 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
8402 Then the expression will be built.
8403 It will be given type FINAL_TYPE if that is nonzero;
8404 otherwise, it will be given type RESULT_TYPE. */
8405
8406 if (!result_type)
8407 {
8408 binary_op_error (code);
8409 return error_mark_node;
8410 }
8411
8412 if (!converted)
8413 {
8414 if (TREE_TYPE (op0) != result_type)
8415 op0 = convert_and_check (result_type, op0);
8416 if (TREE_TYPE (op1) != result_type)
8417 op1 = convert_and_check (result_type, op1);
8418
8419 /* This can happen if one operand has a vector type, and the other
8420 has a different type. */
8421 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
8422 return error_mark_node;
8423 }
8424
8425 if (build_type == NULL_TREE)
8426 build_type = result_type;
8427
8428 {
8429 /* Treat expressions in initializers specially as they can't trap. */
8430 tree result = require_constant_value ? fold_build2_initializer (resultcode,
8431 build_type,
8432 op0, op1)
8433 : fold_build2 (resultcode, build_type,
8434 op0, op1);
8435
8436 if (final_type != 0)
8437 result = convert (final_type, result);
8438 return result;
8439 }
8440 }
8441
8442
8443 /* Convert EXPR to be a truth-value, validating its type for this
8444 purpose. */
8445
8446 tree
8447 c_objc_common_truthvalue_conversion (tree expr)
8448 {
8449 switch (TREE_CODE (TREE_TYPE (expr)))
8450 {
8451 case ARRAY_TYPE:
8452 error ("used array that cannot be converted to pointer where scalar is required");
8453 return error_mark_node;
8454
8455 case RECORD_TYPE:
8456 error ("used struct type value where scalar is required");
8457 return error_mark_node;
8458
8459 case UNION_TYPE:
8460 error ("used union type value where scalar is required");
8461 return error_mark_node;
8462
8463 case FUNCTION_TYPE:
8464 gcc_unreachable ();
8465
8466 default:
8467 break;
8468 }
8469
8470 /* ??? Should we also give an error for void and vectors rather than
8471 leaving those to give errors later? */
8472 return c_common_truthvalue_conversion (expr);
8473 }
8474 \f
8475
8476 /* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as
8477 required. */
8478
8479 tree
8480 c_expr_to_decl (tree expr, bool *tc ATTRIBUTE_UNUSED,
8481 bool *ti ATTRIBUTE_UNUSED, bool *se)
8482 {
8483 if (TREE_CODE (expr) == COMPOUND_LITERAL_EXPR)
8484 {
8485 tree decl = COMPOUND_LITERAL_EXPR_DECL (expr);
8486 /* Executing a compound literal inside a function reinitializes
8487 it. */
8488 if (!TREE_STATIC (decl))
8489 *se = true;
8490 return decl;
8491 }
8492 else
8493 return expr;
8494 }
8495 \f
8496 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
8497
8498 tree
8499 c_begin_omp_parallel (void)
8500 {
8501 tree block;
8502
8503 keep_next_level ();
8504 block = c_begin_compound_stmt (true);
8505
8506 return block;
8507 }
8508
8509 tree
8510 c_finish_omp_parallel (tree clauses, tree block)
8511 {
8512 tree stmt;
8513
8514 block = c_end_compound_stmt (block, true);
8515
8516 stmt = make_node (OMP_PARALLEL);
8517 TREE_TYPE (stmt) = void_type_node;
8518 OMP_PARALLEL_CLAUSES (stmt) = clauses;
8519 OMP_PARALLEL_BODY (stmt) = block;
8520
8521 return add_stmt (stmt);
8522 }
8523
8524 /* For all elements of CLAUSES, validate them vs OpenMP constraints.
8525 Remove any elements from the list that are invalid. */
8526
8527 tree
8528 c_finish_omp_clauses (tree clauses)
8529 {
8530 bitmap_head generic_head, firstprivate_head, lastprivate_head;
8531 tree c, t, *pc = &clauses;
8532 const char *name;
8533
8534 bitmap_obstack_initialize (NULL);
8535 bitmap_initialize (&generic_head, &bitmap_default_obstack);
8536 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack);
8537 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack);
8538
8539 for (pc = &clauses, c = clauses; c ; c = *pc)
8540 {
8541 bool remove = false;
8542 bool need_complete = false;
8543 bool need_implicitly_determined = false;
8544
8545 switch (OMP_CLAUSE_CODE (c))
8546 {
8547 case OMP_CLAUSE_SHARED:
8548 name = "shared";
8549 need_implicitly_determined = true;
8550 goto check_dup_generic;
8551
8552 case OMP_CLAUSE_PRIVATE:
8553 name = "private";
8554 need_complete = true;
8555 need_implicitly_determined = true;
8556 goto check_dup_generic;
8557
8558 case OMP_CLAUSE_REDUCTION:
8559 name = "reduction";
8560 need_implicitly_determined = true;
8561 t = OMP_CLAUSE_DECL (c);
8562 if (AGGREGATE_TYPE_P (TREE_TYPE (t))
8563 || POINTER_TYPE_P (TREE_TYPE (t)))
8564 {
8565 error ("%qE has invalid type for %<reduction%>", t);
8566 remove = true;
8567 }
8568 else if (FLOAT_TYPE_P (TREE_TYPE (t)))
8569 {
8570 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c);
8571 const char *r_name = NULL;
8572
8573 switch (r_code)
8574 {
8575 case PLUS_EXPR:
8576 case MULT_EXPR:
8577 case MINUS_EXPR:
8578 break;
8579 case BIT_AND_EXPR:
8580 r_name = "&";
8581 break;
8582 case BIT_XOR_EXPR:
8583 r_name = "^";
8584 break;
8585 case BIT_IOR_EXPR:
8586 r_name = "|";
8587 break;
8588 case TRUTH_ANDIF_EXPR:
8589 r_name = "&&";
8590 break;
8591 case TRUTH_ORIF_EXPR:
8592 r_name = "||";
8593 break;
8594 default:
8595 gcc_unreachable ();
8596 }
8597 if (r_name)
8598 {
8599 error ("%qE has invalid type for %<reduction(%s)%>",
8600 t, r_name);
8601 remove = true;
8602 }
8603 }
8604 goto check_dup_generic;
8605
8606 case OMP_CLAUSE_COPYPRIVATE:
8607 name = "copyprivate";
8608 goto check_dup_generic;
8609
8610 case OMP_CLAUSE_COPYIN:
8611 name = "copyin";
8612 t = OMP_CLAUSE_DECL (c);
8613 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t))
8614 {
8615 error ("%qE must be %<threadprivate%> for %<copyin%>", t);
8616 remove = true;
8617 }
8618 goto check_dup_generic;
8619
8620 check_dup_generic:
8621 t = OMP_CLAUSE_DECL (c);
8622 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8623 {
8624 error ("%qE is not a variable in clause %qs", t, name);
8625 remove = true;
8626 }
8627 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8628 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))
8629 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
8630 {
8631 error ("%qE appears more than once in data clauses", t);
8632 remove = true;
8633 }
8634 else
8635 bitmap_set_bit (&generic_head, DECL_UID (t));
8636 break;
8637
8638 case OMP_CLAUSE_FIRSTPRIVATE:
8639 name = "firstprivate";
8640 t = OMP_CLAUSE_DECL (c);
8641 need_complete = true;
8642 need_implicitly_determined = true;
8643 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8644 {
8645 error ("%qE is not a variable in clause %<firstprivate%>", t);
8646 remove = true;
8647 }
8648 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8649 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)))
8650 {
8651 error ("%qE appears more than once in data clauses", t);
8652 remove = true;
8653 }
8654 else
8655 bitmap_set_bit (&firstprivate_head, DECL_UID (t));
8656 break;
8657
8658 case OMP_CLAUSE_LASTPRIVATE:
8659 name = "lastprivate";
8660 t = OMP_CLAUSE_DECL (c);
8661 need_complete = true;
8662 need_implicitly_determined = true;
8663 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8664 {
8665 error ("%qE is not a variable in clause %<lastprivate%>", t);
8666 remove = true;
8667 }
8668 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8669 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
8670 {
8671 error ("%qE appears more than once in data clauses", t);
8672 remove = true;
8673 }
8674 else
8675 bitmap_set_bit (&lastprivate_head, DECL_UID (t));
8676 break;
8677
8678 case OMP_CLAUSE_IF:
8679 case OMP_CLAUSE_NUM_THREADS:
8680 case OMP_CLAUSE_SCHEDULE:
8681 case OMP_CLAUSE_NOWAIT:
8682 case OMP_CLAUSE_ORDERED:
8683 case OMP_CLAUSE_DEFAULT:
8684 pc = &OMP_CLAUSE_CHAIN (c);
8685 continue;
8686
8687 default:
8688 gcc_unreachable ();
8689 }
8690
8691 if (!remove)
8692 {
8693 t = OMP_CLAUSE_DECL (c);
8694
8695 if (need_complete)
8696 {
8697 t = require_complete_type (t);
8698 if (t == error_mark_node)
8699 remove = true;
8700 }
8701
8702 if (need_implicitly_determined)
8703 {
8704 const char *share_name = NULL;
8705
8706 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t))
8707 share_name = "threadprivate";
8708 else switch (c_omp_predetermined_sharing (t))
8709 {
8710 case OMP_CLAUSE_DEFAULT_UNSPECIFIED:
8711 break;
8712 case OMP_CLAUSE_DEFAULT_SHARED:
8713 share_name = "shared";
8714 break;
8715 case OMP_CLAUSE_DEFAULT_PRIVATE:
8716 share_name = "private";
8717 break;
8718 default:
8719 gcc_unreachable ();
8720 }
8721 if (share_name)
8722 {
8723 error ("%qE is predetermined %qs for %qs",
8724 t, share_name, name);
8725 remove = true;
8726 }
8727 }
8728 }
8729
8730 if (remove)
8731 *pc = OMP_CLAUSE_CHAIN (c);
8732 else
8733 pc = &OMP_CLAUSE_CHAIN (c);
8734 }
8735
8736 bitmap_obstack_release (NULL);
8737 return clauses;
8738 }
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