1 /* Build expressions with type checking for C compiler.
2 Copyright (C) 1987, 1988, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
4 Free Software Foundation, Inc.
5
6 This file is part of GCC.
7
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 2, or (at your option) any later
11 version.
12
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to the Free
20 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
21 02110-1301, USA. */
22
23
24 /* This file is part of the C front end.
25 It contains routines to build C expressions given their operands,
26 including computing the types of the result, C-specific error checks,
27 and some optimization. */
28
29 #include "config.h"
30 #include "system.h"
31 #include "coretypes.h"
32 #include "tm.h"
33 #include "rtl.h"
34 #include "tree.h"
35 #include "langhooks.h"
36 #include "c-tree.h"
37 #include "tm_p.h"
38 #include "flags.h"
39 #include "output.h"
40 #include "expr.h"
41 #include "toplev.h"
42 #include "intl.h"
43 #include "ggc.h"
44 #include "target.h"
45 #include "tree-iterator.h"
46 #include "tree-gimple.h"
47 #include "tree-flow.h"
48
49 /* Possible cases of implicit bad conversions. Used to select
50 diagnostic messages in convert_for_assignment. */
51 enum impl_conv {
52 ic_argpass,
53 ic_argpass_nonproto,
54 ic_assign,
55 ic_init,
56 ic_return
57 };
58
59 /* The level of nesting inside "__alignof__". */
60 int in_alignof;
61
62 /* The level of nesting inside "sizeof". */
63 int in_sizeof;
64
65 /* The level of nesting inside "typeof". */
66 int in_typeof;
67
68 struct c_label_context_se *label_context_stack_se;
69 struct c_label_context_vm *label_context_stack_vm;
70
71 /* Nonzero if we've already printed a "missing braces around initializer"
72 message within this initializer. */
73 static int missing_braces_mentioned;
74
75 static int require_constant_value;
76 static int require_constant_elements;
77
78 static bool null_pointer_constant_p (tree);
79 static tree qualify_type (tree, tree);
80 static int tagged_types_tu_compatible_p (tree, tree);
81 static int comp_target_types (tree, tree);
82 static int function_types_compatible_p (tree, tree);
83 static int type_lists_compatible_p (tree, tree);
84 static tree decl_constant_value_for_broken_optimization (tree);
85 static tree lookup_field (tree, tree);
86 static tree convert_arguments (tree, tree, tree, tree);
87 static tree pointer_diff (tree, tree);
88 static tree convert_for_assignment (tree, tree, enum impl_conv, tree, tree,
89 int);
90 static tree valid_compound_expr_initializer (tree, tree);
91 static void push_string (const char *);
92 static void push_member_name (tree);
93 static int spelling_length (void);
94 static char *print_spelling (char *);
95 static void warning_init (const char *);
96 static tree digest_init (tree, tree, bool, int);
97 static void output_init_element (tree, bool, tree, tree, int);
98 static void output_pending_init_elements (int);
99 static int set_designator (int);
100 static void push_range_stack (tree);
101 static void add_pending_init (tree, tree);
102 static void set_nonincremental_init (void);
103 static void set_nonincremental_init_from_string (tree);
104 static tree find_init_member (tree);
105 static void readonly_error (tree, enum lvalue_use);
106 static int lvalue_or_else (tree, enum lvalue_use);
107 static int lvalue_p (tree);
108 static void record_maybe_used_decl (tree);
109 static int comptypes_internal (tree, tree);
110
111 /* Return true if EXP is a null pointer constant, false otherwise. */
112
113 static bool
null_pointer_constant_p(tree expr)114 null_pointer_constant_p (tree expr)
115 {
116 /* This should really operate on c_expr structures, but they aren't
117 yet available everywhere required. */
118 tree type = TREE_TYPE (expr);
119 return (TREE_CODE (expr) == INTEGER_CST
120 && !TREE_CONSTANT_OVERFLOW (expr)
121 && integer_zerop (expr)
122 && (INTEGRAL_TYPE_P (type)
123 || (TREE_CODE (type) == POINTER_TYPE
124 && VOID_TYPE_P (TREE_TYPE (type))
125 && TYPE_QUALS (TREE_TYPE (type)) == TYPE_UNQUALIFIED)));
126 }
127 /* 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
require_complete_type(tree value)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
c_incomplete_type_error(tree value,tree type)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
c_type_promotes_to(tree type)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
qualify_type(tree type,tree like)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
c_vla_type_p(tree t)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
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
composite_type(tree t1,tree t2)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
common_pointer_type(tree t1,tree t2)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
c_common_type(tree t1,tree t2)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
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
common_type(tree t1,tree t2)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
comptypes(tree type1,tree type2)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
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
comptypes_internal(tree type1,tree type2)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
comp_target_types(tree ttl,tree ttr)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
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
same_translation_unit_p(tree t1,tree t2)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 *
alloc_tagged_tu_seen_cache(tree t1,tree t2)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
free_all_tagged_tu_seen_up_to(const struct tagged_tu_seen_cache * tu_til)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
tagged_types_tu_compatible_p(tree t1,tree t2)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
function_types_compatible_p(tree f1,tree f2)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
type_lists_compatible_p(tree args1,tree args2)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
1416 /* Compute the size to increment a pointer by. */
1417
1418 static tree
c_size_in_bytes(tree type)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
1438 /* Return either DECL or its known constant value (if it has one). */
1439
1440 tree
decl_constant_value(tree decl)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
decl_constant_value_for_broken_optimization(tree decl)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
array_to_pointer_conversion(tree exp)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
function_to_pointer_conversion(tree exp)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
default_function_array_conversion(struct c_expr exp)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
perform_integral_promotions(tree exp)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
default_conversion(tree exp)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
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
lookup_field(tree decl,tree component)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
build_component_ref(tree datum,tree component)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 /* APPLE LOCAL begin "unavailable" attribute (radar 2809697) */
1853 if (TREE_UNAVAILABLE (subdatum))
1854 error_unavailable_use (subdatum);
1855 /* APPLE LOCAL end "unavailable" attribute (radar 2809697) */
1856
1857 datum = ref;
1858
1859 field = TREE_CHAIN (field);
1860 }
1861 while (field);
1862
1863 return ref;
1864 }
1865 else if (code != ERROR_MARK)
1866 error ("request for member %qE in something not a structure or union",
1867 component);
1868
1869 return error_mark_node;
1870 }
1871
1872 /* Given an expression PTR for a pointer, return an expression
1873 for the value pointed to.
1874 ERRORSTRING is the name of the operator to appear in error messages. */
1875
1876 tree
build_indirect_ref(tree ptr,const char * errorstring)1877 build_indirect_ref (tree ptr, const char *errorstring)
1878 {
1879 tree pointer = default_conversion (ptr);
1880 tree type = TREE_TYPE (pointer);
1881
1882 if (TREE_CODE (type) == POINTER_TYPE)
1883 {
1884 if (TREE_CODE (pointer) == CONVERT_EXPR
1885 || TREE_CODE (pointer) == NOP_EXPR
1886 || TREE_CODE (pointer) == VIEW_CONVERT_EXPR)
1887 {
1888 /* If a warning is issued, mark it to avoid duplicates from
1889 the backend. This only needs to be done at
1890 warn_strict_aliasing > 2. */
1891 if (warn_strict_aliasing > 2)
1892 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (pointer, 0)),
1893 type, TREE_OPERAND (pointer, 0)))
1894 TREE_NO_WARNING (pointer) = 1;
1895 }
1896
1897 if (TREE_CODE (pointer) == ADDR_EXPR
1898 && (TREE_TYPE (TREE_OPERAND (pointer, 0))
1899 == TREE_TYPE (type)))
1900 return TREE_OPERAND (pointer, 0);
1901 else
1902 {
1903 tree t = TREE_TYPE (type);
1904 tree ref;
1905
1906 ref = build1 (INDIRECT_REF, t, pointer);
1907
1908 if (!COMPLETE_OR_VOID_TYPE_P (t) && TREE_CODE (t) != ARRAY_TYPE)
1909 {
1910 error ("dereferencing pointer to incomplete type");
1911 return error_mark_node;
1912 }
1913 if (VOID_TYPE_P (t) && skip_evaluation == 0)
1914 warning (0, "dereferencing %<void *%> pointer");
1915
1916 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
1917 so that we get the proper error message if the result is used
1918 to assign to. Also, &* is supposed to be a no-op.
1919 And ANSI C seems to specify that the type of the result
1920 should be the const type. */
1921 /* A de-reference of a pointer to const is not a const. It is valid
1922 to change it via some other pointer. */
1923 TREE_READONLY (ref) = TYPE_READONLY (t);
1924 TREE_SIDE_EFFECTS (ref)
1925 = TYPE_VOLATILE (t) || TREE_SIDE_EFFECTS (pointer);
1926 TREE_THIS_VOLATILE (ref) = TYPE_VOLATILE (t);
1927 return ref;
1928 }
1929 }
1930 else if (TREE_CODE (pointer) != ERROR_MARK)
1931 error ("invalid type argument of %qs (have %qT)", errorstring, type);
1932 return error_mark_node;
1933 }
1934
1935 /* This handles expressions of the form "a[i]", which denotes
1936 an array reference.
1937
1938 This is logically equivalent in C to *(a+i), but we may do it differently.
1939 If A is a variable or a member, we generate a primitive ARRAY_REF.
1940 This avoids forcing the array out of registers, and can work on
1941 arrays that are not lvalues (for example, members of structures returned
1942 by functions). */
1943
1944 tree
build_array_ref(tree array,tree index)1945 build_array_ref (tree array, tree index)
1946 {
1947 bool swapped = false;
1948 if (TREE_TYPE (array) == error_mark_node
1949 || TREE_TYPE (index) == error_mark_node)
1950 return error_mark_node;
1951
1952 if (TREE_CODE (TREE_TYPE (array)) != ARRAY_TYPE
1953 && TREE_CODE (TREE_TYPE (array)) != POINTER_TYPE)
1954 {
1955 tree temp;
1956 if (TREE_CODE (TREE_TYPE (index)) != ARRAY_TYPE
1957 && TREE_CODE (TREE_TYPE (index)) != POINTER_TYPE)
1958 {
1959 error ("subscripted value is neither array nor pointer");
1960 return error_mark_node;
1961 }
1962 temp = array;
1963 array = index;
1964 index = temp;
1965 swapped = true;
1966 }
1967
1968 if (!INTEGRAL_TYPE_P (TREE_TYPE (index)))
1969 {
1970 error ("array subscript is not an integer");
1971 return error_mark_node;
1972 }
1973
1974 if (TREE_CODE (TREE_TYPE (TREE_TYPE (array))) == FUNCTION_TYPE)
1975 {
1976 error ("subscripted value is pointer to function");
1977 return error_mark_node;
1978 }
1979
1980 /* ??? Existing practice has been to warn only when the char
1981 index is syntactically the index, not for char[array]. */
1982 if (!swapped)
1983 warn_array_subscript_with_type_char (index);
1984
1985 /* Apply default promotions *after* noticing character types. */
1986 index = default_conversion (index);
1987
1988 gcc_assert (TREE_CODE (TREE_TYPE (index)) == INTEGER_TYPE);
1989
1990 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
1991 {
1992 tree rval, type;
1993
1994 /* An array that is indexed by a non-constant
1995 cannot be stored in a register; we must be able to do
1996 address arithmetic on its address.
1997 Likewise an array of elements of variable size. */
1998 if (TREE_CODE (index) != INTEGER_CST
1999 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2000 && TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array)))) != INTEGER_CST))
2001 {
2002 if (!c_mark_addressable (array))
2003 return error_mark_node;
2004 }
2005 /* An array that is indexed by a constant value which is not within
2006 the array bounds cannot be stored in a register either; because we
2007 would get a crash in store_bit_field/extract_bit_field when trying
2008 to access a non-existent part of the register. */
2009 if (TREE_CODE (index) == INTEGER_CST
2010 && TYPE_DOMAIN (TREE_TYPE (array))
2011 && !int_fits_type_p (index, TYPE_DOMAIN (TREE_TYPE (array))))
2012 {
2013 if (!c_mark_addressable (array))
2014 return error_mark_node;
2015 }
2016
2017 if (pedantic)
2018 {
2019 tree foo = array;
2020 while (TREE_CODE (foo) == COMPONENT_REF)
2021 foo = TREE_OPERAND (foo, 0);
2022 if (TREE_CODE (foo) == VAR_DECL && C_DECL_REGISTER (foo))
2023 pedwarn ("ISO C forbids subscripting %<register%> array");
2024 else if (!flag_isoc99 && !lvalue_p (foo))
2025 pedwarn ("ISO C90 forbids subscripting non-lvalue array");
2026 }
2027
2028 type = TREE_TYPE (TREE_TYPE (array));
2029 if (TREE_CODE (type) != ARRAY_TYPE)
2030 type = TYPE_MAIN_VARIANT (type);
2031 rval = build4 (ARRAY_REF, type, array, index, NULL_TREE, NULL_TREE);
2032 /* Array ref is const/volatile if the array elements are
2033 or if the array is. */
2034 TREE_READONLY (rval)
2035 |= (TYPE_READONLY (TREE_TYPE (TREE_TYPE (array)))
2036 | TREE_READONLY (array));
2037 TREE_SIDE_EFFECTS (rval)
2038 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2039 | TREE_SIDE_EFFECTS (array));
2040 TREE_THIS_VOLATILE (rval)
2041 |= (TYPE_VOLATILE (TREE_TYPE (TREE_TYPE (array)))
2042 /* This was added by rms on 16 Nov 91.
2043 It fixes vol struct foo *a; a->elts[1]
2044 in an inline function.
2045 Hope it doesn't break something else. */
2046 | TREE_THIS_VOLATILE (array));
2047 return require_complete_type (fold (rval));
2048 }
2049 else
2050 {
2051 tree ar = default_conversion (array);
2052
2053 if (ar == error_mark_node)
2054 return ar;
2055
2056 gcc_assert (TREE_CODE (TREE_TYPE (ar)) == POINTER_TYPE);
2057 gcc_assert (TREE_CODE (TREE_TYPE (TREE_TYPE (ar))) != FUNCTION_TYPE);
2058
2059 return build_indirect_ref (build_binary_op (PLUS_EXPR, ar, index, 0),
2060 "array indexing");
2061 }
2062 }
2063
2064 /* Build an external reference to identifier ID. FUN indicates
2065 whether this will be used for a function call. LOC is the source
2066 location of the identifier. */
2067 tree
build_external_ref(tree id,int fun,location_t loc)2068 build_external_ref (tree id, int fun, location_t loc)
2069 {
2070 tree ref;
2071 tree decl = lookup_name (id);
2072
2073 /* In Objective-C, an instance variable (ivar) may be preferred to
2074 whatever lookup_name() found. */
2075 decl = objc_lookup_ivar (decl, id);
2076
2077 if (decl && decl != error_mark_node)
2078 ref = decl;
2079 else if (fun)
2080 /* Implicit function declaration. */
2081 ref = implicitly_declare (id);
2082 else if (decl == error_mark_node)
2083 /* Don't complain about something that's already been
2084 complained about. */
2085 return error_mark_node;
2086 else
2087 {
2088 undeclared_variable (id, loc);
2089 return error_mark_node;
2090 }
2091
2092 if (TREE_TYPE (ref) == error_mark_node)
2093 return error_mark_node;
2094
2095 if (TREE_DEPRECATED (ref))
2096 warn_deprecated_use (ref);
2097
2098 /* APPLE LOCAL begin "unavailable" attribute (radar 2809697) */
2099 if (TREE_UNAVAILABLE (ref))
2100 error_unavailable_use (ref);
2101 /* APPLE LOCAL end "unavailable" attribute (radar 2809697) */
2102
2103 if (!skip_evaluation)
2104 assemble_external (ref);
2105 TREE_USED (ref) = 1;
2106
2107 if (TREE_CODE (ref) == FUNCTION_DECL && !in_alignof)
2108 {
2109 if (!in_sizeof && !in_typeof)
2110 C_DECL_USED (ref) = 1;
2111 else if (DECL_INITIAL (ref) == 0
2112 && DECL_EXTERNAL (ref)
2113 && !TREE_PUBLIC (ref))
2114 record_maybe_used_decl (ref);
2115 }
2116
2117 if (TREE_CODE (ref) == CONST_DECL)
2118 {
2119 used_types_insert (TREE_TYPE (ref));
2120 ref = DECL_INITIAL (ref);
2121 TREE_CONSTANT (ref) = 1;
2122 TREE_INVARIANT (ref) = 1;
2123 }
2124 else if (current_function_decl != 0
2125 && !DECL_FILE_SCOPE_P (current_function_decl)
2126 && (TREE_CODE (ref) == VAR_DECL
2127 || TREE_CODE (ref) == PARM_DECL
2128 || TREE_CODE (ref) == FUNCTION_DECL))
2129 {
2130 tree context = decl_function_context (ref);
2131
2132 if (context != 0 && context != current_function_decl)
2133 DECL_NONLOCAL (ref) = 1;
2134 }
2135 /* C99 6.7.4p3: An inline definition of a function with external
2136 linkage ... shall not contain a reference to an identifier with
2137 internal linkage. */
2138 else if (current_function_decl != 0
2139 && DECL_DECLARED_INLINE_P (current_function_decl)
2140 && DECL_EXTERNAL (current_function_decl)
2141 && VAR_OR_FUNCTION_DECL_P (ref)
2142 && DECL_FILE_SCOPE_P (ref)
2143 && pedantic
2144 && (TREE_CODE (ref) != VAR_DECL || TREE_STATIC (ref))
2145 && ! TREE_PUBLIC (ref))
2146 pedwarn ("%H%qD is static but used in inline function %qD "
2147 "which is not static", &loc, ref, current_function_decl);
2148
2149 return ref;
2150 }
2151
2152 /* Record details of decls possibly used inside sizeof or typeof. */
2153 struct maybe_used_decl
2154 {
2155 /* The decl. */
2156 tree decl;
2157 /* The level seen at (in_sizeof + in_typeof). */
2158 int level;
2159 /* The next one at this level or above, or NULL. */
2160 struct maybe_used_decl *next;
2161 };
2162
2163 static struct maybe_used_decl *maybe_used_decls;
2164
2165 /* Record that DECL, an undefined static function reference seen
2166 inside sizeof or typeof, might be used if the operand of sizeof is
2167 a VLA type or the operand of typeof is a variably modified
2168 type. */
2169
2170 static void
record_maybe_used_decl(tree decl)2171 record_maybe_used_decl (tree decl)
2172 {
2173 struct maybe_used_decl *t = XOBNEW (&parser_obstack, struct maybe_used_decl);
2174 t->decl = decl;
2175 t->level = in_sizeof + in_typeof;
2176 t->next = maybe_used_decls;
2177 maybe_used_decls = t;
2178 }
2179
2180 /* Pop the stack of decls possibly used inside sizeof or typeof. If
2181 USED is false, just discard them. If it is true, mark them used
2182 (if no longer inside sizeof or typeof) or move them to the next
2183 level up (if still inside sizeof or typeof). */
2184
2185 void
pop_maybe_used(bool used)2186 pop_maybe_used (bool used)
2187 {
2188 struct maybe_used_decl *p = maybe_used_decls;
2189 int cur_level = in_sizeof + in_typeof;
2190 while (p && p->level > cur_level)
2191 {
2192 if (used)
2193 {
2194 if (cur_level == 0)
2195 C_DECL_USED (p->decl) = 1;
2196 else
2197 p->level = cur_level;
2198 }
2199 p = p->next;
2200 }
2201 if (!used || cur_level == 0)
2202 maybe_used_decls = p;
2203 }
2204
2205 /* Return the result of sizeof applied to EXPR. */
2206
2207 struct c_expr
c_expr_sizeof_expr(struct c_expr expr)2208 c_expr_sizeof_expr (struct c_expr expr)
2209 {
2210 struct c_expr ret;
2211 if (expr.value == error_mark_node)
2212 {
2213 ret.value = error_mark_node;
2214 ret.original_code = ERROR_MARK;
2215 pop_maybe_used (false);
2216 }
2217 else
2218 {
2219 ret.value = c_sizeof (TREE_TYPE (expr.value));
2220 ret.original_code = ERROR_MARK;
2221 if (c_vla_type_p (TREE_TYPE (expr.value)))
2222 {
2223 /* sizeof is evaluated when given a vla (C99 6.5.3.4p2). */
2224 ret.value = build2 (COMPOUND_EXPR, TREE_TYPE (ret.value), expr.value, ret.value);
2225 }
2226 pop_maybe_used (C_TYPE_VARIABLE_SIZE (TREE_TYPE (expr.value)));
2227 }
2228 return ret;
2229 }
2230
2231 /* Return the result of sizeof applied to T, a structure for the type
2232 name passed to sizeof (rather than the type itself). */
2233
2234 struct c_expr
c_expr_sizeof_type(struct c_type_name * t)2235 c_expr_sizeof_type (struct c_type_name *t)
2236 {
2237 tree type;
2238 struct c_expr ret;
2239 type = groktypename (t);
2240 ret.value = c_sizeof (type);
2241 ret.original_code = ERROR_MARK;
2242 pop_maybe_used (type != error_mark_node
2243 ? C_TYPE_VARIABLE_SIZE (type) : false);
2244 return ret;
2245 }
2246
2247 /* Build a function call to function FUNCTION with parameters PARAMS.
2248 PARAMS is a list--a chain of TREE_LIST nodes--in which the
2249 TREE_VALUE of each node is a parameter-expression.
2250 FUNCTION's data type may be a function type or a pointer-to-function. */
2251
2252 tree
build_function_call(tree function,tree params)2253 build_function_call (tree function, tree params)
2254 {
2255 tree fntype, fundecl = 0;
2256 tree coerced_params;
2257 tree name = NULL_TREE, result;
2258 tree tem;
2259
2260 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2261 STRIP_TYPE_NOPS (function);
2262
2263 /* Convert anything with function type to a pointer-to-function. */
2264 if (TREE_CODE (function) == FUNCTION_DECL)
2265 {
2266 /* Implement type-directed function overloading for builtins.
2267 resolve_overloaded_builtin and targetm.resolve_overloaded_builtin
2268 handle all the type checking. The result is a complete expression
2269 that implements this function call. */
2270 tem = resolve_overloaded_builtin (function, params);
2271 if (tem)
2272 return tem;
2273
2274 name = DECL_NAME (function);
2275 fundecl = function;
2276 }
2277 if (TREE_CODE (TREE_TYPE (function)) == FUNCTION_TYPE)
2278 function = function_to_pointer_conversion (function);
2279
2280 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2281 expressions, like those used for ObjC messenger dispatches. */
2282 function = objc_rewrite_function_call (function, params);
2283
2284 fntype = TREE_TYPE (function);
2285
2286 if (TREE_CODE (fntype) == ERROR_MARK)
2287 return error_mark_node;
2288
2289 if (!(TREE_CODE (fntype) == POINTER_TYPE
2290 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE))
2291 {
2292 error ("called object %qE is not a function", function);
2293 return error_mark_node;
2294 }
2295
2296 if (fundecl && TREE_THIS_VOLATILE (fundecl))
2297 current_function_returns_abnormally = 1;
2298
2299 /* fntype now gets the type of function pointed to. */
2300 fntype = TREE_TYPE (fntype);
2301
2302 /* Check that the function is called through a compatible prototype.
2303 If it is not, replace the call by a trap, wrapped up in a compound
2304 expression if necessary. This has the nice side-effect to prevent
2305 the tree-inliner from generating invalid assignment trees which may
2306 blow up in the RTL expander later. */
2307 if ((TREE_CODE (function) == NOP_EXPR
2308 || TREE_CODE (function) == CONVERT_EXPR)
2309 && TREE_CODE (tem = TREE_OPERAND (function, 0)) == ADDR_EXPR
2310 && TREE_CODE (tem = TREE_OPERAND (tem, 0)) == FUNCTION_DECL
2311 && !comptypes (fntype, TREE_TYPE (tem)))
2312 {
2313 tree return_type = TREE_TYPE (fntype);
2314 tree trap = build_function_call (built_in_decls[BUILT_IN_TRAP],
2315 NULL_TREE);
2316
2317 /* This situation leads to run-time undefined behavior. We can't,
2318 therefore, simply error unless we can prove that all possible
2319 executions of the program must execute the code. */
2320 warning (0, "function called through a non-compatible type");
2321
2322 /* We can, however, treat "undefined" any way we please.
2323 Call abort to encourage the user to fix the program. */
2324 inform ("if this code is reached, the program will abort");
2325
2326 if (VOID_TYPE_P (return_type))
2327 return trap;
2328 else
2329 {
2330 tree rhs;
2331
2332 if (AGGREGATE_TYPE_P (return_type))
2333 rhs = build_compound_literal (return_type,
2334 build_constructor (return_type, 0));
2335 else
2336 rhs = fold_convert (return_type, integer_zero_node);
2337
2338 return build2 (COMPOUND_EXPR, return_type, trap, rhs);
2339 }
2340 }
2341
2342 /* Convert the parameters to the types declared in the
2343 function prototype, or apply default promotions. */
2344
2345 coerced_params
2346 = convert_arguments (TYPE_ARG_TYPES (fntype), params, function, fundecl);
2347
2348 if (coerced_params == error_mark_node)
2349 return error_mark_node;
2350
2351 /* Check that the arguments to the function are valid. */
2352
2353 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params,
2354 TYPE_ARG_TYPES (fntype));
2355
2356 if (require_constant_value)
2357 {
2358 result = fold_build3_initializer (CALL_EXPR, TREE_TYPE (fntype),
2359 function, coerced_params, NULL_TREE);
2360
2361 if (TREE_CONSTANT (result)
2362 && (name == NULL_TREE
2363 || strncmp (IDENTIFIER_POINTER (name), "__builtin_", 10) != 0))
2364 pedwarn_init ("initializer element is not constant");
2365 }
2366 else
2367 result = fold_build3 (CALL_EXPR, TREE_TYPE (fntype),
2368 function, coerced_params, NULL_TREE);
2369
2370 if (VOID_TYPE_P (TREE_TYPE (result)))
2371 return result;
2372 return require_complete_type (result);
2373 }
2374
2375 /* Convert the argument expressions in the list VALUES
2376 to the types in the list TYPELIST. The result is a list of converted
2377 argument expressions, unless there are too few arguments in which
2378 case it is error_mark_node.
2379
2380 If TYPELIST is exhausted, or when an element has NULL as its type,
2381 perform the default conversions.
2382
2383 PARMLIST is the chain of parm decls for the function being called.
2384 It may be 0, if that info is not available.
2385 It is used only for generating error messages.
2386
2387 FUNCTION is a tree for the called function. It is used only for
2388 error messages, where it is formatted with %qE.
2389
2390 This is also where warnings about wrong number of args are generated.
2391
2392 Both VALUES and the returned value are chains of TREE_LIST nodes
2393 with the elements of the list in the TREE_VALUE slots of those nodes. */
2394
2395 static tree
convert_arguments(tree typelist,tree values,tree function,tree fundecl)2396 convert_arguments (tree typelist, tree values, tree function, tree fundecl)
2397 {
2398 tree typetail, valtail;
2399 tree result = NULL;
2400 int parmnum;
2401 tree selector;
2402
2403 /* Change pointer to function to the function itself for
2404 diagnostics. */
2405 if (TREE_CODE (function) == ADDR_EXPR
2406 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
2407 function = TREE_OPERAND (function, 0);
2408
2409 /* Handle an ObjC selector specially for diagnostics. */
2410 selector = objc_message_selector ();
2411
2412 /* Scan the given expressions and types, producing individual
2413 converted arguments and pushing them on RESULT in reverse order. */
2414
2415 for (valtail = values, typetail = typelist, parmnum = 0;
2416 valtail;
2417 valtail = TREE_CHAIN (valtail), parmnum++)
2418 {
2419 tree type = typetail ? TREE_VALUE (typetail) : 0;
2420 tree val = TREE_VALUE (valtail);
2421 tree rname = function;
2422 int argnum = parmnum + 1;
2423 const char *invalid_func_diag;
2424
2425 if (type == void_type_node)
2426 {
2427 error ("too many arguments to function %qE", function);
2428 break;
2429 }
2430
2431 if (selector && argnum > 2)
2432 {
2433 rname = selector;
2434 argnum -= 2;
2435 }
2436
2437 STRIP_TYPE_NOPS (val);
2438
2439 val = require_complete_type (val);
2440
2441 if (type != 0)
2442 {
2443 /* Formal parm type is specified by a function prototype. */
2444 tree parmval;
2445
2446 if (type == error_mark_node || !COMPLETE_TYPE_P (type))
2447 {
2448 error ("type of formal parameter %d is incomplete", parmnum + 1);
2449 parmval = val;
2450 }
2451 else
2452 {
2453 /* Optionally warn about conversions that
2454 differ from the default conversions. */
2455 if (warn_conversion || warn_traditional)
2456 {
2457 unsigned int formal_prec = TYPE_PRECISION (type);
2458
2459 if (INTEGRAL_TYPE_P (type)
2460 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2461 warning (0, "passing argument %d of %qE as integer "
2462 "rather than floating due to prototype",
2463 argnum, rname);
2464 if (INTEGRAL_TYPE_P (type)
2465 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2466 warning (0, "passing argument %d of %qE as integer "
2467 "rather than complex due to prototype",
2468 argnum, rname);
2469 else if (TREE_CODE (type) == COMPLEX_TYPE
2470 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2471 warning (0, "passing argument %d of %qE as complex "
2472 "rather than floating due to prototype",
2473 argnum, rname);
2474 else if (TREE_CODE (type) == REAL_TYPE
2475 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2476 warning (0, "passing argument %d of %qE as floating "
2477 "rather than integer due to prototype",
2478 argnum, rname);
2479 else if (TREE_CODE (type) == COMPLEX_TYPE
2480 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2481 warning (0, "passing argument %d of %qE as complex "
2482 "rather than integer due to prototype",
2483 argnum, rname);
2484 else if (TREE_CODE (type) == REAL_TYPE
2485 && TREE_CODE (TREE_TYPE (val)) == COMPLEX_TYPE)
2486 warning (0, "passing argument %d of %qE as floating "
2487 "rather than complex due to prototype",
2488 argnum, rname);
2489 /* ??? At some point, messages should be written about
2490 conversions between complex types, but that's too messy
2491 to do now. */
2492 else if (TREE_CODE (type) == REAL_TYPE
2493 && TREE_CODE (TREE_TYPE (val)) == REAL_TYPE)
2494 {
2495 /* Warn if any argument is passed as `float',
2496 since without a prototype it would be `double'. */
2497 if (formal_prec == TYPE_PRECISION (float_type_node)
2498 && type != dfloat32_type_node)
2499 warning (0, "passing argument %d of %qE as %<float%> "
2500 "rather than %<double%> due to prototype",
2501 argnum, rname);
2502
2503 /* Warn if mismatch between argument and prototype
2504 for decimal float types. Warn of conversions with
2505 binary float types and of precision narrowing due to
2506 prototype. */
2507 else if (type != TREE_TYPE (val)
2508 && (type == dfloat32_type_node
2509 || type == dfloat64_type_node
2510 || type == dfloat128_type_node
2511 || TREE_TYPE (val) == dfloat32_type_node
2512 || TREE_TYPE (val) == dfloat64_type_node
2513 || TREE_TYPE (val) == dfloat128_type_node)
2514 && (formal_prec
2515 <= TYPE_PRECISION (TREE_TYPE (val))
2516 || (type == dfloat128_type_node
2517 && (TREE_TYPE (val)
2518 != dfloat64_type_node
2519 && (TREE_TYPE (val)
2520 != dfloat32_type_node)))
2521 || (type == dfloat64_type_node
2522 && (TREE_TYPE (val)
2523 != dfloat32_type_node))))
2524 warning (0, "passing argument %d of %qE as %qT "
2525 "rather than %qT due to prototype",
2526 argnum, rname, type, TREE_TYPE (val));
2527
2528 }
2529 /* Detect integer changing in width or signedness.
2530 These warnings are only activated with
2531 -Wconversion, not with -Wtraditional. */
2532 else if (warn_conversion && INTEGRAL_TYPE_P (type)
2533 && INTEGRAL_TYPE_P (TREE_TYPE (val)))
2534 {
2535 tree would_have_been = default_conversion (val);
2536 tree type1 = TREE_TYPE (would_have_been);
2537
2538 if (TREE_CODE (type) == ENUMERAL_TYPE
2539 && (TYPE_MAIN_VARIANT (type)
2540 == TYPE_MAIN_VARIANT (TREE_TYPE (val))))
2541 /* No warning if function asks for enum
2542 and the actual arg is that enum type. */
2543 ;
2544 else if (formal_prec != TYPE_PRECISION (type1))
2545 warning (OPT_Wconversion, "passing argument %d of %qE "
2546 "with different width due to prototype",
2547 argnum, rname);
2548 else if (TYPE_UNSIGNED (type) == TYPE_UNSIGNED (type1))
2549 ;
2550 /* Don't complain if the formal parameter type
2551 is an enum, because we can't tell now whether
2552 the value was an enum--even the same enum. */
2553 else if (TREE_CODE (type) == ENUMERAL_TYPE)
2554 ;
2555 else if (TREE_CODE (val) == INTEGER_CST
2556 && int_fits_type_p (val, type))
2557 /* Change in signedness doesn't matter
2558 if a constant value is unaffected. */
2559 ;
2560 /* If the value is extended from a narrower
2561 unsigned type, it doesn't matter whether we
2562 pass it as signed or unsigned; the value
2563 certainly is the same either way. */
2564 else if (TYPE_PRECISION (TREE_TYPE (val)) < TYPE_PRECISION (type)
2565 && TYPE_UNSIGNED (TREE_TYPE (val)))
2566 ;
2567 else if (TYPE_UNSIGNED (type))
2568 warning (OPT_Wconversion, "passing argument %d of %qE "
2569 "as unsigned due to prototype",
2570 argnum, rname);
2571 else
2572 warning (OPT_Wconversion, "passing argument %d of %qE "
2573 "as signed due to prototype", argnum, rname);
2574 }
2575 }
2576
2577 parmval = convert_for_assignment (type, val, ic_argpass,
2578 fundecl, function,
2579 parmnum + 1);
2580
2581 if (targetm.calls.promote_prototypes (fundecl ? TREE_TYPE (fundecl) : 0)
2582 && INTEGRAL_TYPE_P (type)
2583 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
2584 parmval = default_conversion (parmval);
2585 }
2586 result = tree_cons (NULL_TREE, parmval, result);
2587 }
2588 else if (TREE_CODE (TREE_TYPE (val)) == REAL_TYPE
2589 && (TYPE_PRECISION (TREE_TYPE (val))
2590 < TYPE_PRECISION (double_type_node))
2591 && !DECIMAL_FLOAT_MODE_P (TYPE_MODE (TREE_TYPE (val))))
2592 /* Convert `float' to `double'. */
2593 result = tree_cons (NULL_TREE, convert (double_type_node, val), result);
2594 else if ((invalid_func_diag =
2595 targetm.calls.invalid_arg_for_unprototyped_fn (typelist, fundecl, val)))
2596 {
2597 error (invalid_func_diag, "");
2598 return error_mark_node;
2599 }
2600 else
2601 /* Convert `short' and `char' to full-size `int'. */
2602 result = tree_cons (NULL_TREE, default_conversion (val), result);
2603
2604 if (typetail)
2605 typetail = TREE_CHAIN (typetail);
2606 }
2607
2608 if (typetail != 0 && TREE_VALUE (typetail) != void_type_node)
2609 {
2610 error ("too few arguments to function %qE", function);
2611 return error_mark_node;
2612 }
2613
2614 return nreverse (result);
2615 }
2616
2617 /* This is the entry point used by the parser to build unary operators
2618 in the input. CODE, a tree_code, specifies the unary operator, and
2619 ARG is the operand. For unary plus, the C parser currently uses
2620 CONVERT_EXPR for code. */
2621
2622 struct c_expr
parser_build_unary_op(enum tree_code code,struct c_expr arg)2623 parser_build_unary_op (enum tree_code code, struct c_expr arg)
2624 {
2625 struct c_expr result;
2626
2627 result.original_code = ERROR_MARK;
2628 result.value = build_unary_op (code, arg.value, 0);
2629
2630 if (TREE_OVERFLOW_P (result.value) && !TREE_OVERFLOW_P (arg.value))
2631 overflow_warning (result.value);
2632
2633 return result;
2634 }
2635
2636 /* This is the entry point used by the parser to build binary operators
2637 in the input. CODE, a tree_code, specifies the binary operator, and
2638 ARG1 and ARG2 are the operands. In addition to constructing the
2639 expression, we check for operands that were written with other binary
2640 operators in a way that is likely to confuse the user. */
2641
2642 struct c_expr
parser_build_binary_op(enum tree_code code,struct c_expr arg1,struct c_expr arg2)2643 parser_build_binary_op (enum tree_code code, struct c_expr arg1,
2644 struct c_expr arg2)
2645 {
2646 struct c_expr result;
2647
2648 enum tree_code code1 = arg1.original_code;
2649 enum tree_code code2 = arg2.original_code;
2650
2651 result.value = build_binary_op (code, arg1.value, arg2.value, 1);
2652 result.original_code = code;
2653
2654 if (TREE_CODE (result.value) == ERROR_MARK)
2655 return result;
2656
2657 /* Check for cases such as x+y<<z which users are likely
2658 to misinterpret. */
2659 if (warn_parentheses)
2660 warn_about_parentheses (code, code1, code2);
2661
2662 /* Warn about comparisons against string literals, with the exception
2663 of testing for equality or inequality of a string literal with NULL. */
2664 if (code == EQ_EXPR || code == NE_EXPR)
2665 {
2666 if ((code1 == STRING_CST && !integer_zerop (arg2.value))
2667 || (code2 == STRING_CST && !integer_zerop (arg1.value)))
2668 warning (OPT_Waddress,
2669 "comparison with string literal results in unspecified behaviour");
2670 }
2671 else if (TREE_CODE_CLASS (code) == tcc_comparison
2672 && (code1 == STRING_CST || code2 == STRING_CST))
2673 warning (OPT_Waddress,
2674 "comparison with string literal results in unspecified behaviour");
2675
2676 if (TREE_OVERFLOW_P (result.value)
2677 && !TREE_OVERFLOW_P (arg1.value)
2678 && !TREE_OVERFLOW_P (arg2.value))
2679 overflow_warning (result.value);
2680
2681 return result;
2682 }
2683
2684 /* Return a tree for the difference of pointers OP0 and OP1.
2685 The resulting tree has type int. */
2686
2687 static tree
pointer_diff(tree op0,tree op1)2688 pointer_diff (tree op0, tree op1)
2689 {
2690 tree restype = ptrdiff_type_node;
2691
2692 tree target_type = TREE_TYPE (TREE_TYPE (op0));
2693 tree con0, con1, lit0, lit1;
2694 tree orig_op1 = op1;
2695
2696 if (pedantic || warn_pointer_arith)
2697 {
2698 if (TREE_CODE (target_type) == VOID_TYPE)
2699 pedwarn ("pointer of type %<void *%> used in subtraction");
2700 if (TREE_CODE (target_type) == FUNCTION_TYPE)
2701 pedwarn ("pointer to a function used in subtraction");
2702 }
2703
2704 /* If the conversion to ptrdiff_type does anything like widening or
2705 converting a partial to an integral mode, we get a convert_expression
2706 that is in the way to do any simplifications.
2707 (fold-const.c doesn't know that the extra bits won't be needed.
2708 split_tree uses STRIP_SIGN_NOPS, which leaves conversions to a
2709 different mode in place.)
2710 So first try to find a common term here 'by hand'; we want to cover
2711 at least the cases that occur in legal static initializers. */
2712 if ((TREE_CODE (op0) == NOP_EXPR || TREE_CODE (op0) == CONVERT_EXPR)
2713 && (TYPE_PRECISION (TREE_TYPE (op0))
2714 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op0, 0)))))
2715 con0 = TREE_OPERAND (op0, 0);
2716 else
2717 con0 = op0;
2718 if ((TREE_CODE (op1) == NOP_EXPR || TREE_CODE (op1) == CONVERT_EXPR)
2719 && (TYPE_PRECISION (TREE_TYPE (op1))
2720 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op1, 0)))))
2721 con1 = TREE_OPERAND (op1, 0);
2722 else
2723 con1 = op1;
2724
2725 if (TREE_CODE (con0) == PLUS_EXPR)
2726 {
2727 lit0 = TREE_OPERAND (con0, 1);
2728 con0 = TREE_OPERAND (con0, 0);
2729 }
2730 else
2731 lit0 = integer_zero_node;
2732
2733 if (TREE_CODE (con1) == PLUS_EXPR)
2734 {
2735 lit1 = TREE_OPERAND (con1, 1);
2736 con1 = TREE_OPERAND (con1, 0);
2737 }
2738 else
2739 lit1 = integer_zero_node;
2740
2741 if (operand_equal_p (con0, con1, 0))
2742 {
2743 op0 = lit0;
2744 op1 = lit1;
2745 }
2746
2747
2748 /* First do the subtraction as integers;
2749 then drop through to build the divide operator.
2750 Do not do default conversions on the minus operator
2751 in case restype is a short type. */
2752
2753 op0 = build_binary_op (MINUS_EXPR, convert (restype, op0),
2754 convert (restype, op1), 0);
2755 /* This generates an error if op1 is pointer to incomplete type. */
2756 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (TREE_TYPE (orig_op1))))
2757 error ("arithmetic on pointer to an incomplete type");
2758
2759 /* This generates an error if op0 is pointer to incomplete type. */
2760 op1 = c_size_in_bytes (target_type);
2761
2762 /* Divide by the size, in easiest possible way. */
2763 return fold_build2 (EXACT_DIV_EXPR, restype, op0, convert (restype, op1));
2764 }
2765
2766 /* Construct and perhaps optimize a tree representation
2767 for a unary operation. CODE, a tree_code, specifies the operation
2768 and XARG is the operand.
2769 For any CODE other than ADDR_EXPR, FLAG nonzero suppresses
2770 the default promotions (such as from short to int).
2771 For ADDR_EXPR, the default promotions are not applied; FLAG nonzero
2772 allows non-lvalues; this is only used to handle conversion of non-lvalue
2773 arrays to pointers in C99. */
2774
2775 tree
build_unary_op(enum tree_code code,tree xarg,int flag)2776 build_unary_op (enum tree_code code, tree xarg, int flag)
2777 {
2778 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
2779 tree arg = xarg;
2780 tree argtype = 0;
2781 enum tree_code typecode = TREE_CODE (TREE_TYPE (arg));
2782 tree val;
2783 int noconvert = flag;
2784 const char *invalid_op_diag;
2785
2786 if (typecode == ERROR_MARK)
2787 return error_mark_node;
2788 if (typecode == ENUMERAL_TYPE || typecode == BOOLEAN_TYPE)
2789 typecode = INTEGER_TYPE;
2790
2791 if ((invalid_op_diag
2792 = targetm.invalid_unary_op (code, TREE_TYPE (xarg))))
2793 {
2794 error (invalid_op_diag, "");
2795 return error_mark_node;
2796 }
2797
2798 switch (code)
2799 {
2800 case CONVERT_EXPR:
2801 /* This is used for unary plus, because a CONVERT_EXPR
2802 is enough to prevent anybody from looking inside for
2803 associativity, but won't generate any code. */
2804 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2805 || typecode == COMPLEX_TYPE
2806 || typecode == VECTOR_TYPE))
2807 {
2808 error ("wrong type argument to unary plus");
2809 return error_mark_node;
2810 }
2811 else if (!noconvert)
2812 arg = default_conversion (arg);
2813 arg = non_lvalue (arg);
2814 break;
2815
2816 case NEGATE_EXPR:
2817 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2818 || typecode == COMPLEX_TYPE
2819 || typecode == VECTOR_TYPE))
2820 {
2821 error ("wrong type argument to unary minus");
2822 return error_mark_node;
2823 }
2824 else if (!noconvert)
2825 arg = default_conversion (arg);
2826 break;
2827
2828 case BIT_NOT_EXPR:
2829 if (typecode == INTEGER_TYPE || typecode == VECTOR_TYPE)
2830 {
2831 if (!noconvert)
2832 arg = default_conversion (arg);
2833 }
2834 else if (typecode == COMPLEX_TYPE)
2835 {
2836 code = CONJ_EXPR;
2837 if (pedantic)
2838 pedwarn ("ISO C does not support %<~%> for complex conjugation");
2839 if (!noconvert)
2840 arg = default_conversion (arg);
2841 }
2842 else
2843 {
2844 error ("wrong type argument to bit-complement");
2845 return error_mark_node;
2846 }
2847 break;
2848
2849 case ABS_EXPR:
2850 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE))
2851 {
2852 error ("wrong type argument to abs");
2853 return error_mark_node;
2854 }
2855 else if (!noconvert)
2856 arg = default_conversion (arg);
2857 break;
2858
2859 case CONJ_EXPR:
2860 /* Conjugating a real value is a no-op, but allow it anyway. */
2861 if (!(typecode == INTEGER_TYPE || typecode == REAL_TYPE
2862 || typecode == COMPLEX_TYPE))
2863 {
2864 error ("wrong type argument to conjugation");
2865 return error_mark_node;
2866 }
2867 else if (!noconvert)
2868 arg = default_conversion (arg);
2869 break;
2870
2871 case TRUTH_NOT_EXPR:
2872 if (typecode != INTEGER_TYPE
2873 && typecode != REAL_TYPE && typecode != POINTER_TYPE
2874 && typecode != COMPLEX_TYPE)
2875 {
2876 error ("wrong type argument to unary exclamation mark");
2877 return error_mark_node;
2878 }
2879 arg = c_objc_common_truthvalue_conversion (arg);
2880 return invert_truthvalue (arg);
2881
2882 case REALPART_EXPR:
2883 if (TREE_CODE (arg) == COMPLEX_CST)
2884 return TREE_REALPART (arg);
2885 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2886 return fold_build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
2887 else
2888 return arg;
2889
2890 case IMAGPART_EXPR:
2891 if (TREE_CODE (arg) == COMPLEX_CST)
2892 return TREE_IMAGPART (arg);
2893 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
2894 return fold_build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
2895 else
2896 return convert (TREE_TYPE (arg), integer_zero_node);
2897
2898 case PREINCREMENT_EXPR:
2899 case POSTINCREMENT_EXPR:
2900 case PREDECREMENT_EXPR:
2901 case POSTDECREMENT_EXPR:
2902
2903 /* Increment or decrement the real part of the value,
2904 and don't change the imaginary part. */
2905 if (typecode == COMPLEX_TYPE)
2906 {
2907 tree real, imag;
2908
2909 if (pedantic)
2910 pedwarn ("ISO C does not support %<++%> and %<--%>"
2911 " on complex types");
2912
2913 arg = stabilize_reference (arg);
2914 real = build_unary_op (REALPART_EXPR, arg, 1);
2915 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
2916 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
2917 build_unary_op (code, real, 1), imag);
2918 }
2919
2920 /* Report invalid types. */
2921
2922 if (typecode != POINTER_TYPE
2923 && typecode != INTEGER_TYPE && typecode != REAL_TYPE)
2924 {
2925 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2926 error ("wrong type argument to increment");
2927 else
2928 error ("wrong type argument to decrement");
2929
2930 return error_mark_node;
2931 }
2932
2933 {
2934 tree inc;
2935 tree result_type = TREE_TYPE (arg);
2936
2937 arg = get_unwidened (arg, 0);
2938 argtype = TREE_TYPE (arg);
2939
2940 /* Compute the increment. */
2941
2942 if (typecode == POINTER_TYPE)
2943 {
2944 /* If pointer target is an undefined struct,
2945 we just cannot know how to do the arithmetic. */
2946 if (!COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (result_type)))
2947 {
2948 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2949 error ("increment of pointer to unknown structure");
2950 else
2951 error ("decrement of pointer to unknown structure");
2952 }
2953 else if ((pedantic || warn_pointer_arith)
2954 && (TREE_CODE (TREE_TYPE (result_type)) == FUNCTION_TYPE
2955 || TREE_CODE (TREE_TYPE (result_type)) == VOID_TYPE))
2956 {
2957 if (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
2958 pedwarn ("wrong type argument to increment");
2959 else
2960 pedwarn ("wrong type argument to decrement");
2961 }
2962
2963 inc = c_size_in_bytes (TREE_TYPE (result_type));
2964 }
2965 else
2966 inc = integer_one_node;
2967
2968 inc = convert (argtype, inc);
2969
2970 /* Complain about anything else that is not a true lvalue. */
2971 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
2972 || code == POSTINCREMENT_EXPR)
2973 ? lv_increment
2974 : lv_decrement)))
2975 return error_mark_node;
2976
2977 /* Report a read-only lvalue. */
2978 if (TREE_READONLY (arg))
2979 {
2980 readonly_error (arg,
2981 ((code == PREINCREMENT_EXPR
2982 || code == POSTINCREMENT_EXPR)
2983 ? lv_increment : lv_decrement));
2984 return error_mark_node;
2985 }
2986
2987 if (TREE_CODE (TREE_TYPE (arg)) == BOOLEAN_TYPE)
2988 val = boolean_increment (code, arg);
2989 else
2990 val = build2 (code, TREE_TYPE (arg), arg, inc);
2991 TREE_SIDE_EFFECTS (val) = 1;
2992 val = convert (result_type, val);
2993 if (TREE_CODE (val) != code)
2994 TREE_NO_WARNING (val) = 1;
2995 return val;
2996 }
2997
2998 case ADDR_EXPR:
2999 /* Note that this operation never does default_conversion. */
3000
3001 /* Let &* cancel out to simplify resulting code. */
3002 if (TREE_CODE (arg) == INDIRECT_REF)
3003 {
3004 /* Don't let this be an lvalue. */
3005 if (lvalue_p (TREE_OPERAND (arg, 0)))
3006 return non_lvalue (TREE_OPERAND (arg, 0));
3007 return TREE_OPERAND (arg, 0);
3008 }
3009
3010 /* For &x[y], return x+y */
3011 if (TREE_CODE (arg) == ARRAY_REF)
3012 {
3013 tree op0 = TREE_OPERAND (arg, 0);
3014 if (!c_mark_addressable (op0))
3015 return error_mark_node;
3016 return build_binary_op (PLUS_EXPR,
3017 (TREE_CODE (TREE_TYPE (op0)) == ARRAY_TYPE
3018 ? array_to_pointer_conversion (op0)
3019 : op0),
3020 TREE_OPERAND (arg, 1), 1);
3021 }
3022
3023 /* Anything not already handled and not a true memory reference
3024 or a non-lvalue array is an error. */
3025 else if (typecode != FUNCTION_TYPE && !flag
3026 && !lvalue_or_else (arg, lv_addressof))
3027 return error_mark_node;
3028
3029 /* Ordinary case; arg is a COMPONENT_REF or a decl. */
3030 argtype = TREE_TYPE (arg);
3031
3032 /* If the lvalue is const or volatile, merge that into the type
3033 to which the address will point. Note that you can't get a
3034 restricted pointer by taking the address of something, so we
3035 only have to deal with `const' and `volatile' here. */
3036 if ((DECL_P (arg) || REFERENCE_CLASS_P (arg))
3037 && (TREE_READONLY (arg) || TREE_THIS_VOLATILE (arg)))
3038 argtype = c_build_type_variant (argtype,
3039 TREE_READONLY (arg),
3040 TREE_THIS_VOLATILE (arg));
3041
3042 if (!c_mark_addressable (arg))
3043 return error_mark_node;
3044
3045 gcc_assert (TREE_CODE (arg) != COMPONENT_REF
3046 || !DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)));
3047
3048 argtype = build_pointer_type (argtype);
3049
3050 /* ??? Cope with user tricks that amount to offsetof. Delete this
3051 when we have proper support for integer constant expressions. */
3052 val = get_base_address (arg);
3053 if (val && TREE_CODE (val) == INDIRECT_REF
3054 && TREE_CONSTANT (TREE_OPERAND (val, 0)))
3055 {
3056 tree op0 = fold_convert (argtype, fold_offsetof (arg, val)), op1;
3057
3058 op1 = fold_convert (argtype, TREE_OPERAND (val, 0));
3059 return fold_build2 (PLUS_EXPR, argtype, op0, op1);
3060 }
3061
3062 val = build1 (ADDR_EXPR, argtype, arg);
3063
3064 return val;
3065
3066 default:
3067 gcc_unreachable ();
3068 }
3069
3070 if (argtype == 0)
3071 argtype = TREE_TYPE (arg);
3072 return require_constant_value ? fold_build1_initializer (code, argtype, arg)
3073 : fold_build1 (code, argtype, arg);
3074 }
3075
3076 /* Return nonzero if REF is an lvalue valid for this language.
3077 Lvalues can be assigned, unless their type has TYPE_READONLY.
3078 Lvalues can have their address taken, unless they have C_DECL_REGISTER. */
3079
3080 static int
lvalue_p(tree ref)3081 lvalue_p (tree ref)
3082 {
3083 enum tree_code code = TREE_CODE (ref);
3084
3085 switch (code)
3086 {
3087 case REALPART_EXPR:
3088 case IMAGPART_EXPR:
3089 case COMPONENT_REF:
3090 return lvalue_p (TREE_OPERAND (ref, 0));
3091
3092 case COMPOUND_LITERAL_EXPR:
3093 case STRING_CST:
3094 return 1;
3095
3096 case INDIRECT_REF:
3097 case ARRAY_REF:
3098 case VAR_DECL:
3099 case PARM_DECL:
3100 case RESULT_DECL:
3101 case ERROR_MARK:
3102 return (TREE_CODE (TREE_TYPE (ref)) != FUNCTION_TYPE
3103 && TREE_CODE (TREE_TYPE (ref)) != METHOD_TYPE);
3104
3105 case BIND_EXPR:
3106 return TREE_CODE (TREE_TYPE (ref)) == ARRAY_TYPE;
3107
3108 default:
3109 return 0;
3110 }
3111 }
3112
3113 /* Give an error for storing in something that is 'const'. */
3114
3115 static void
readonly_error(tree arg,enum lvalue_use use)3116 readonly_error (tree arg, enum lvalue_use use)
3117 {
3118 gcc_assert (use == lv_assign || use == lv_increment || use == lv_decrement
3119 || use == lv_asm);
3120 /* Using this macro rather than (for example) arrays of messages
3121 ensures that all the format strings are checked at compile
3122 time. */
3123 #define READONLY_MSG(A, I, D, AS) (use == lv_assign ? (A) \
3124 : (use == lv_increment ? (I) \
3125 : (use == lv_decrement ? (D) : (AS))))
3126 if (TREE_CODE (arg) == COMPONENT_REF)
3127 {
3128 if (TYPE_READONLY (TREE_TYPE (TREE_OPERAND (arg, 0))))
3129 readonly_error (TREE_OPERAND (arg, 0), use);
3130 else
3131 error (READONLY_MSG (G_("assignment of read-only member %qD"),
3132 G_("increment of read-only member %qD"),
3133 G_("decrement of read-only member %qD"),
3134 G_("read-only member %qD used as %<asm%> output")),
3135 TREE_OPERAND (arg, 1));
3136 }
3137 else if (TREE_CODE (arg) == VAR_DECL)
3138 error (READONLY_MSG (G_("assignment of read-only variable %qD"),
3139 G_("increment of read-only variable %qD"),
3140 G_("decrement of read-only variable %qD"),
3141 G_("read-only variable %qD used as %<asm%> output")),
3142 arg);
3143 else
3144 error (READONLY_MSG (G_("assignment of read-only location"),
3145 G_("increment of read-only location"),
3146 G_("decrement of read-only location"),
3147 G_("read-only location used as %<asm%> output")));
3148 }
3149
3150
3151 /* Return nonzero if REF is an lvalue valid for this language;
3152 otherwise, print an error message and return zero. USE says
3153 how the lvalue is being used and so selects the error message. */
3154
3155 static int
lvalue_or_else(tree ref,enum lvalue_use use)3156 lvalue_or_else (tree ref, enum lvalue_use use)
3157 {
3158 int win = lvalue_p (ref);
3159
3160 if (!win)
3161 lvalue_error (use);
3162
3163 return win;
3164 }
3165
3166 /* Mark EXP saying that we need to be able to take the
3167 address of it; it should not be allocated in a register.
3168 Returns true if successful. */
3169
3170 bool
c_mark_addressable(tree exp)3171 c_mark_addressable (tree exp)
3172 {
3173 tree x = exp;
3174
3175 while (1)
3176 switch (TREE_CODE (x))
3177 {
3178 case COMPONENT_REF:
3179 if (DECL_C_BIT_FIELD (TREE_OPERAND (x, 1)))
3180 {
3181 error
3182 ("cannot take address of bit-field %qD", TREE_OPERAND (x, 1));
3183 return false;
3184 }
3185
3186 /* ... fall through ... */
3187
3188 case ADDR_EXPR:
3189 case ARRAY_REF:
3190 case REALPART_EXPR:
3191 case IMAGPART_EXPR:
3192 x = TREE_OPERAND (x, 0);
3193 break;
3194
3195 case COMPOUND_LITERAL_EXPR:
3196 case CONSTRUCTOR:
3197 TREE_ADDRESSABLE (x) = 1;
3198 return true;
3199
3200 case VAR_DECL:
3201 case CONST_DECL:
3202 case PARM_DECL:
3203 case RESULT_DECL:
3204 if (C_DECL_REGISTER (x)
3205 && DECL_NONLOCAL (x))
3206 {
3207 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3208 {
3209 error
3210 ("global register variable %qD used in nested function", x);
3211 return false;
3212 }
3213 pedwarn ("register variable %qD used in nested function", x);
3214 }
3215 else if (C_DECL_REGISTER (x))
3216 {
3217 if (TREE_PUBLIC (x) || TREE_STATIC (x) || DECL_EXTERNAL (x))
3218 error ("address of global register variable %qD requested", x);
3219 else
3220 error ("address of register variable %qD requested", x);
3221 return false;
3222 }
3223
3224 /* drops in */
3225 case FUNCTION_DECL:
3226 TREE_ADDRESSABLE (x) = 1;
3227 /* drops out */
3228 default:
3229 return true;
3230 }
3231 }
3232
3233 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
3234
3235 tree
build_conditional_expr(tree ifexp,tree op1,tree op2)3236 build_conditional_expr (tree ifexp, tree op1, tree op2)
3237 {
3238 tree type1;
3239 tree type2;
3240 enum tree_code code1;
3241 enum tree_code code2;
3242 tree result_type = NULL;
3243 tree orig_op1 = op1, orig_op2 = op2;
3244
3245 /* Promote both alternatives. */
3246
3247 if (TREE_CODE (TREE_TYPE (op1)) != VOID_TYPE)
3248 op1 = default_conversion (op1);
3249 if (TREE_CODE (TREE_TYPE (op2)) != VOID_TYPE)
3250 op2 = default_conversion (op2);
3251
3252 if (TREE_CODE (ifexp) == ERROR_MARK
3253 || TREE_CODE (TREE_TYPE (op1)) == ERROR_MARK
3254 || TREE_CODE (TREE_TYPE (op2)) == ERROR_MARK)
3255 return error_mark_node;
3256
3257 type1 = TREE_TYPE (op1);
3258 code1 = TREE_CODE (type1);
3259 type2 = TREE_TYPE (op2);
3260 code2 = TREE_CODE (type2);
3261
3262 /* C90 does not permit non-lvalue arrays in conditional expressions.
3263 In C99 they will be pointers by now. */
3264 if (code1 == ARRAY_TYPE || code2 == ARRAY_TYPE)
3265 {
3266 error ("non-lvalue array in conditional expression");
3267 return error_mark_node;
3268 }
3269
3270 /* Quickly detect the usual case where op1 and op2 have the same type
3271 after promotion. */
3272 if (TYPE_MAIN_VARIANT (type1) == TYPE_MAIN_VARIANT (type2))
3273 {
3274 if (type1 == type2)
3275 result_type = type1;
3276 else
3277 result_type = TYPE_MAIN_VARIANT (type1);
3278 }
3279 else if ((code1 == INTEGER_TYPE || code1 == REAL_TYPE
3280 || code1 == COMPLEX_TYPE)
3281 && (code2 == INTEGER_TYPE || code2 == REAL_TYPE
3282 || code2 == COMPLEX_TYPE))
3283 {
3284 result_type = c_common_type (type1, type2);
3285
3286 /* If -Wsign-compare, warn here if type1 and type2 have
3287 different signedness. We'll promote the signed to unsigned
3288 and later code won't know it used to be different.
3289 Do this check on the original types, so that explicit casts
3290 will be considered, but default promotions won't. */
3291 if (warn_sign_compare && !skip_evaluation)
3292 {
3293 int unsigned_op1 = TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3294 int unsigned_op2 = TYPE_UNSIGNED (TREE_TYPE (orig_op2));
3295
3296 if (unsigned_op1 ^ unsigned_op2)
3297 {
3298 bool ovf;
3299
3300 /* Do not warn if the result type is signed, since the
3301 signed type will only be chosen if it can represent
3302 all the values of the unsigned type. */
3303 if (!TYPE_UNSIGNED (result_type))
3304 /* OK */;
3305 /* Do not warn if the signed quantity is an unsuffixed
3306 integer literal (or some static constant expression
3307 involving such literals) and it is non-negative. */
3308 else if ((unsigned_op2
3309 && tree_expr_nonnegative_warnv_p (op1, &ovf))
3310 || (unsigned_op1
3311 && tree_expr_nonnegative_warnv_p (op2, &ovf)))
3312 /* OK */;
3313 else
3314 warning (0, "signed and unsigned type in conditional expression");
3315 }
3316 }
3317 }
3318 else if (code1 == VOID_TYPE || code2 == VOID_TYPE)
3319 {
3320 if (pedantic && (code1 != VOID_TYPE || code2 != VOID_TYPE))
3321 pedwarn ("ISO C forbids conditional expr with only one void side");
3322 result_type = void_type_node;
3323 }
3324 else if (code1 == POINTER_TYPE && code2 == POINTER_TYPE)
3325 {
3326 if (comp_target_types (type1, type2))
3327 result_type = common_pointer_type (type1, type2);
3328 else if (null_pointer_constant_p (orig_op1))
3329 result_type = qualify_type (type2, type1);
3330 else if (null_pointer_constant_p (orig_op2))
3331 result_type = qualify_type (type1, type2);
3332 else if (VOID_TYPE_P (TREE_TYPE (type1)))
3333 {
3334 if (pedantic && TREE_CODE (TREE_TYPE (type2)) == FUNCTION_TYPE)
3335 pedwarn ("ISO C forbids conditional expr between "
3336 "%<void *%> and function pointer");
3337 result_type = build_pointer_type (qualify_type (TREE_TYPE (type1),
3338 TREE_TYPE (type2)));
3339 }
3340 else if (VOID_TYPE_P (TREE_TYPE (type2)))
3341 {
3342 if (pedantic && TREE_CODE (TREE_TYPE (type1)) == FUNCTION_TYPE)
3343 pedwarn ("ISO C forbids conditional expr between "
3344 "%<void *%> and function pointer");
3345 result_type = build_pointer_type (qualify_type (TREE_TYPE (type2),
3346 TREE_TYPE (type1)));
3347 }
3348 else
3349 {
3350 pedwarn ("pointer type mismatch in conditional expression");
3351 result_type = build_pointer_type (void_type_node);
3352 }
3353 }
3354 else if (code1 == POINTER_TYPE && code2 == INTEGER_TYPE)
3355 {
3356 if (!null_pointer_constant_p (orig_op2))
3357 pedwarn ("pointer/integer type mismatch in conditional expression");
3358 else
3359 {
3360 op2 = null_pointer_node;
3361 }
3362 result_type = type1;
3363 }
3364 else if (code2 == POINTER_TYPE && code1 == INTEGER_TYPE)
3365 {
3366 if (!null_pointer_constant_p (orig_op1))
3367 pedwarn ("pointer/integer type mismatch in conditional expression");
3368 else
3369 {
3370 op1 = null_pointer_node;
3371 }
3372 result_type = type2;
3373 }
3374
3375 if (!result_type)
3376 {
3377 if (flag_cond_mismatch)
3378 result_type = void_type_node;
3379 else
3380 {
3381 error ("type mismatch in conditional expression");
3382 return error_mark_node;
3383 }
3384 }
3385
3386 /* Merge const and volatile flags of the incoming types. */
3387 result_type
3388 = build_type_variant (result_type,
3389 TREE_READONLY (op1) || TREE_READONLY (op2),
3390 TREE_THIS_VOLATILE (op1) || TREE_THIS_VOLATILE (op2));
3391
3392 if (result_type != TREE_TYPE (op1))
3393 op1 = convert_and_check (result_type, op1);
3394 if (result_type != TREE_TYPE (op2))
3395 op2 = convert_and_check (result_type, op2);
3396
3397 return fold_build3 (COND_EXPR, result_type, ifexp, op1, op2);
3398 }
3399
3400 /* Return a compound expression that performs two expressions and
3401 returns the value of the second of them. */
3402
3403 tree
build_compound_expr(tree expr1,tree expr2)3404 build_compound_expr (tree expr1, tree expr2)
3405 {
3406 if (!TREE_SIDE_EFFECTS (expr1))
3407 {
3408 /* The left-hand operand of a comma expression is like an expression
3409 statement: with -Wextra or -Wunused, we should warn if it doesn't have
3410 any side-effects, unless it was explicitly cast to (void). */
3411 if (warn_unused_value)
3412 {
3413 if (VOID_TYPE_P (TREE_TYPE (expr1))
3414 && (TREE_CODE (expr1) == NOP_EXPR
3415 || TREE_CODE (expr1) == CONVERT_EXPR))
3416 ; /* (void) a, b */
3417 else if (VOID_TYPE_P (TREE_TYPE (expr1))
3418 && TREE_CODE (expr1) == COMPOUND_EXPR
3419 && (TREE_CODE (TREE_OPERAND (expr1, 1)) == CONVERT_EXPR
3420 || TREE_CODE (TREE_OPERAND (expr1, 1)) == NOP_EXPR))
3421 ; /* (void) a, (void) b, c */
3422 else
3423 warning (0, "left-hand operand of comma expression has no effect");
3424 }
3425 }
3426
3427 /* With -Wunused, we should also warn if the left-hand operand does have
3428 side-effects, but computes a value which is not used. For example, in
3429 `foo() + bar(), baz()' the result of the `+' operator is not used,
3430 so we should issue a warning. */
3431 else if (warn_unused_value)
3432 warn_if_unused_value (expr1, input_location);
3433
3434 if (expr2 == error_mark_node)
3435 return error_mark_node;
3436
3437 return build2 (COMPOUND_EXPR, TREE_TYPE (expr2), expr1, expr2);
3438 }
3439
3440 /* Build an expression representing a cast to type TYPE of expression EXPR. */
3441
3442 tree
build_c_cast(tree type,tree expr)3443 build_c_cast (tree type, tree expr)
3444 {
3445 tree value = expr;
3446
3447 if (type == error_mark_node || expr == error_mark_node)
3448 return error_mark_node;
3449
3450 /* The ObjC front-end uses TYPE_MAIN_VARIANT to tie together types differing
3451 only in <protocol> qualifications. But when constructing cast expressions,
3452 the protocols do matter and must be kept around. */
3453 if (objc_is_object_ptr (type) && objc_is_object_ptr (TREE_TYPE (expr)))
3454 return build1 (NOP_EXPR, type, expr);
3455
3456 type = TYPE_MAIN_VARIANT (type);
3457
3458 if (TREE_CODE (type) == ARRAY_TYPE)
3459 {
3460 error ("cast specifies array type");
3461 return error_mark_node;
3462 }
3463
3464 if (TREE_CODE (type) == FUNCTION_TYPE)
3465 {
3466 error ("cast specifies function type");
3467 return error_mark_node;
3468 }
3469
3470 if (type == TYPE_MAIN_VARIANT (TREE_TYPE (value)))
3471 {
3472 if (pedantic)
3473 {
3474 if (TREE_CODE (type) == RECORD_TYPE
3475 || TREE_CODE (type) == UNION_TYPE)
3476 pedwarn ("ISO C forbids casting nonscalar to the same type");
3477 }
3478 }
3479 else if (TREE_CODE (type) == UNION_TYPE)
3480 {
3481 tree field;
3482
3483 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
3484 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (field)),
3485 TYPE_MAIN_VARIANT (TREE_TYPE (value))))
3486 break;
3487
3488 if (field)
3489 {
3490 tree t;
3491
3492 if (pedantic)
3493 pedwarn ("ISO C forbids casts to union type");
3494 t = digest_init (type,
3495 build_constructor_single (type, field, value),
3496 true, 0);
3497 TREE_CONSTANT (t) = TREE_CONSTANT (value);
3498 TREE_INVARIANT (t) = TREE_INVARIANT (value);
3499 return t;
3500 }
3501 error ("cast to union type from type not present in union");
3502 return error_mark_node;
3503 }
3504 else
3505 {
3506 tree otype, ovalue;
3507
3508 if (type == void_type_node)
3509 return build1 (CONVERT_EXPR, type, value);
3510
3511 otype = TREE_TYPE (value);
3512
3513 /* Optionally warn about potentially worrisome casts. */
3514
3515 if (warn_cast_qual
3516 && TREE_CODE (type) == POINTER_TYPE
3517 && TREE_CODE (otype) == POINTER_TYPE)
3518 {
3519 tree in_type = type;
3520 tree in_otype = otype;
3521 int added = 0;
3522 int discarded = 0;
3523
3524 /* Check that the qualifiers on IN_TYPE are a superset of
3525 the qualifiers of IN_OTYPE. The outermost level of
3526 POINTER_TYPE nodes is uninteresting and we stop as soon
3527 as we hit a non-POINTER_TYPE node on either type. */
3528 do
3529 {
3530 in_otype = TREE_TYPE (in_otype);
3531 in_type = TREE_TYPE (in_type);
3532
3533 /* GNU C allows cv-qualified function types. 'const'
3534 means the function is very pure, 'volatile' means it
3535 can't return. We need to warn when such qualifiers
3536 are added, not when they're taken away. */
3537 if (TREE_CODE (in_otype) == FUNCTION_TYPE
3538 && TREE_CODE (in_type) == FUNCTION_TYPE)
3539 added |= (TYPE_QUALS (in_type) & ~TYPE_QUALS (in_otype));
3540 else
3541 discarded |= (TYPE_QUALS (in_otype) & ~TYPE_QUALS (in_type));
3542 }
3543 while (TREE_CODE (in_type) == POINTER_TYPE
3544 && TREE_CODE (in_otype) == POINTER_TYPE);
3545
3546 if (added)
3547 warning (0, "cast adds new qualifiers to function type");
3548
3549 if (discarded)
3550 /* There are qualifiers present in IN_OTYPE that are not
3551 present in IN_TYPE. */
3552 warning (0, "cast discards qualifiers from pointer target type");
3553 }
3554
3555 /* Warn about possible alignment problems. */
3556 if (STRICT_ALIGNMENT
3557 && TREE_CODE (type) == POINTER_TYPE
3558 && TREE_CODE (otype) == POINTER_TYPE
3559 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
3560 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3561 /* Don't warn about opaque types, where the actual alignment
3562 restriction is unknown. */
3563 && !((TREE_CODE (TREE_TYPE (otype)) == UNION_TYPE
3564 || TREE_CODE (TREE_TYPE (otype)) == RECORD_TYPE)
3565 && TYPE_MODE (TREE_TYPE (otype)) == VOIDmode)
3566 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
3567 warning (OPT_Wcast_align,
3568 "cast increases required alignment of target type");
3569
3570 if (TREE_CODE (type) == INTEGER_TYPE
3571 && TREE_CODE (otype) == POINTER_TYPE
3572 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
3573 /* Unlike conversion of integers to pointers, where the
3574 warning is disabled for converting constants because
3575 of cases such as SIG_*, warn about converting constant
3576 pointers to integers. In some cases it may cause unwanted
3577 sign extension, and a warning is appropriate. */
3578 warning (OPT_Wpointer_to_int_cast,
3579 "cast from pointer to integer of different size");
3580
3581 if (TREE_CODE (value) == CALL_EXPR
3582 && TREE_CODE (type) != TREE_CODE (otype))
3583 warning (OPT_Wbad_function_cast, "cast from function call of type %qT "
3584 "to non-matching type %qT", otype, type);
3585
3586 if (TREE_CODE (type) == POINTER_TYPE
3587 && TREE_CODE (otype) == INTEGER_TYPE
3588 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
3589 /* Don't warn about converting any constant. */
3590 && !TREE_CONSTANT (value))
3591 warning (OPT_Wint_to_pointer_cast, "cast to pointer from integer "
3592 "of different size");
3593
3594 if (warn_strict_aliasing <= 2)
3595 strict_aliasing_warning (otype, type, expr);
3596
3597 /* If pedantic, warn for conversions between function and object
3598 pointer types, except for converting a null pointer constant
3599 to function pointer type. */
3600 if (pedantic
3601 && TREE_CODE (type) == POINTER_TYPE
3602 && TREE_CODE (otype) == POINTER_TYPE
3603 && TREE_CODE (TREE_TYPE (otype)) == FUNCTION_TYPE
3604 && TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE)
3605 pedwarn ("ISO C forbids conversion of function pointer to object pointer type");
3606
3607 if (pedantic
3608 && TREE_CODE (type) == POINTER_TYPE
3609 && TREE_CODE (otype) == POINTER_TYPE
3610 && TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
3611 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
3612 && !null_pointer_constant_p (value))
3613 pedwarn ("ISO C forbids conversion of object pointer to function pointer type");
3614
3615 ovalue = value;
3616 value = convert (type, value);
3617
3618 /* Ignore any integer overflow caused by the cast. */
3619 if (TREE_CODE (value) == INTEGER_CST)
3620 {
3621 if (CONSTANT_CLASS_P (ovalue)
3622 && (TREE_OVERFLOW (ovalue) || TREE_CONSTANT_OVERFLOW (ovalue)))
3623 {
3624 /* Avoid clobbering a shared constant. */
3625 value = copy_node (value);
3626 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
3627 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
3628 }
3629 else if (TREE_OVERFLOW (value) || TREE_CONSTANT_OVERFLOW (value))
3630 /* Reset VALUE's overflow flags, ensuring constant sharing. */
3631 value = build_int_cst_wide (TREE_TYPE (value),
3632 TREE_INT_CST_LOW (value),
3633 TREE_INT_CST_HIGH (value));
3634 }
3635 }
3636
3637 /* Don't let a cast be an lvalue. */
3638 if (value == expr)
3639 value = non_lvalue (value);
3640
3641 return value;
3642 }
3643
3644 /* Interpret a cast of expression EXPR to type TYPE. */
3645 tree
c_cast_expr(struct c_type_name * type_name,tree expr)3646 c_cast_expr (struct c_type_name *type_name, tree expr)
3647 {
3648 tree type;
3649 int saved_wsp = warn_strict_prototypes;
3650
3651 /* This avoids warnings about unprototyped casts on
3652 integers. E.g. "#define SIG_DFL (void(*)())0". */
3653 if (TREE_CODE (expr) == INTEGER_CST)
3654 warn_strict_prototypes = 0;
3655 type = groktypename (type_name);
3656 warn_strict_prototypes = saved_wsp;
3657
3658 return build_c_cast (type, expr);
3659 }
3660
3661 /* Build an assignment expression of lvalue LHS from value RHS.
3662 MODIFYCODE is the code for a binary operator that we use
3663 to combine the old value of LHS with RHS to get the new value.
3664 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment. */
3665
3666 tree
build_modify_expr(tree lhs,enum tree_code modifycode,tree rhs)3667 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
3668 {
3669 tree result;
3670 tree newrhs;
3671 tree lhstype = TREE_TYPE (lhs);
3672 tree olhstype = lhstype;
3673
3674 /* Types that aren't fully specified cannot be used in assignments. */
3675 lhs = require_complete_type (lhs);
3676
3677 /* Avoid duplicate error messages from operands that had errors. */
3678 if (TREE_CODE (lhs) == ERROR_MARK || TREE_CODE (rhs) == ERROR_MARK)
3679 return error_mark_node;
3680
3681 if (!lvalue_or_else (lhs, lv_assign))
3682 return error_mark_node;
3683
3684 STRIP_TYPE_NOPS (rhs);
3685
3686 newrhs = rhs;
3687
3688 /* If a binary op has been requested, combine the old LHS value with the RHS
3689 producing the value we should actually store into the LHS. */
3690
3691 if (modifycode != NOP_EXPR)
3692 {
3693 lhs = stabilize_reference (lhs);
3694 newrhs = build_binary_op (modifycode, lhs, rhs, 1);
3695 }
3696
3697 /* Give an error for storing in something that is 'const'. */
3698
3699 if (TREE_READONLY (lhs) || TYPE_READONLY (lhstype)
3700 || ((TREE_CODE (lhstype) == RECORD_TYPE
3701 || TREE_CODE (lhstype) == UNION_TYPE)
3702 && C_TYPE_FIELDS_READONLY (lhstype)))
3703 {
3704 readonly_error (lhs, lv_assign);
3705 return error_mark_node;
3706 }
3707
3708 /* If storing into a structure or union member,
3709 it has probably been given type `int'.
3710 Compute the type that would go with
3711 the actual amount of storage the member occupies. */
3712
3713 if (TREE_CODE (lhs) == COMPONENT_REF
3714 && (TREE_CODE (lhstype) == INTEGER_TYPE
3715 || TREE_CODE (lhstype) == BOOLEAN_TYPE
3716 || TREE_CODE (lhstype) == REAL_TYPE
3717 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
3718 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
3719
3720 /* If storing in a field that is in actuality a short or narrower than one,
3721 we must store in the field in its actual type. */
3722
3723 if (lhstype != TREE_TYPE (lhs))
3724 {
3725 lhs = copy_node (lhs);
3726 TREE_TYPE (lhs) = lhstype;
3727 }
3728
3729 /* Convert new value to destination type. */
3730
3731 newrhs = convert_for_assignment (lhstype, newrhs, ic_assign,
3732 NULL_TREE, NULL_TREE, 0);
3733 if (TREE_CODE (newrhs) == ERROR_MARK)
3734 return error_mark_node;
3735
3736 /* Emit ObjC write barrier, if necessary. */
3737 if (c_dialect_objc () && flag_objc_gc)
3738 {
3739 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
3740 if (result)
3741 return result;
3742 }
3743
3744 /* Scan operands. */
3745
3746 result = build2 (MODIFY_EXPR, lhstype, lhs, newrhs);
3747 TREE_SIDE_EFFECTS (result) = 1;
3748
3749 /* If we got the LHS in a different type for storing in,
3750 convert the result back to the nominal type of LHS
3751 so that the value we return always has the same type
3752 as the LHS argument. */
3753
3754 if (olhstype == TREE_TYPE (result))
3755 return result;
3756 return convert_for_assignment (olhstype, result, ic_assign,
3757 NULL_TREE, NULL_TREE, 0);
3758 }
3759
3760 /* Convert value RHS to type TYPE as preparation for an assignment
3761 to an lvalue of type TYPE.
3762 The real work of conversion is done by `convert'.
3763 The purpose of this function is to generate error messages
3764 for assignments that are not allowed in C.
3765 ERRTYPE says whether it is argument passing, assignment,
3766 initialization or return.
3767
3768 FUNCTION is a tree for the function being called.
3769 PARMNUM is the number of the argument, for printing in error messages. */
3770
3771 static tree
convert_for_assignment(tree type,tree rhs,enum impl_conv errtype,tree fundecl,tree function,int parmnum)3772 convert_for_assignment (tree type, tree rhs, enum impl_conv errtype,
3773 tree fundecl, tree function, int parmnum)
3774 {
3775 enum tree_code codel = TREE_CODE (type);
3776 tree rhstype;
3777 enum tree_code coder;
3778 tree rname = NULL_TREE;
3779 bool objc_ok = false;
3780
3781 if (errtype == ic_argpass || errtype == ic_argpass_nonproto)
3782 {
3783 tree selector;
3784 /* Change pointer to function to the function itself for
3785 diagnostics. */
3786 if (TREE_CODE (function) == ADDR_EXPR
3787 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL)
3788 function = TREE_OPERAND (function, 0);
3789
3790 /* Handle an ObjC selector specially for diagnostics. */
3791 selector = objc_message_selector ();
3792 rname = function;
3793 if (selector && parmnum > 2)
3794 {
3795 rname = selector;
3796 parmnum -= 2;
3797 }
3798 }
3799
3800 /* This macro is used to emit diagnostics to ensure that all format
3801 strings are complete sentences, visible to gettext and checked at
3802 compile time. */
3803 #define WARN_FOR_ASSIGNMENT(AR, AS, IN, RE) \
3804 do { \
3805 switch (errtype) \
3806 { \
3807 case ic_argpass: \
3808 pedwarn (AR, parmnum, rname); \
3809 break; \
3810 case ic_argpass_nonproto: \
3811 warning (0, AR, parmnum, rname); \
3812 break; \
3813 case ic_assign: \
3814 pedwarn (AS); \
3815 break; \
3816 case ic_init: \
3817 pedwarn (IN); \
3818 break; \
3819 case ic_return: \
3820 pedwarn (RE); \
3821 break; \
3822 default: \
3823 gcc_unreachable (); \
3824 } \
3825 } while (0)
3826
3827 STRIP_TYPE_NOPS (rhs);
3828
3829 if (optimize && TREE_CODE (rhs) == VAR_DECL
3830 && TREE_CODE (TREE_TYPE (rhs)) != ARRAY_TYPE)
3831 rhs = decl_constant_value_for_broken_optimization (rhs);
3832
3833 rhstype = TREE_TYPE (rhs);
3834 coder = TREE_CODE (rhstype);
3835
3836 if (coder == ERROR_MARK)
3837 return error_mark_node;
3838
3839 if (c_dialect_objc ())
3840 {
3841 int parmno;
3842
3843 switch (errtype)
3844 {
3845 case ic_return:
3846 parmno = 0;
3847 break;
3848
3849 case ic_assign:
3850 parmno = -1;
3851 break;
3852
3853 case ic_init:
3854 parmno = -2;
3855 break;
3856
3857 default:
3858 parmno = parmnum;
3859 break;
3860 }
3861
3862 objc_ok = objc_compare_types (type, rhstype, parmno, rname);
3863 }
3864
3865 if (TYPE_MAIN_VARIANT (type) == TYPE_MAIN_VARIANT (rhstype))
3866 return rhs;
3867
3868 if (coder == VOID_TYPE)
3869 {
3870 /* Except for passing an argument to an unprototyped function,
3871 this is a constraint violation. When passing an argument to
3872 an unprototyped function, it is compile-time undefined;
3873 making it a constraint in that case was rejected in
3874 DR#252. */
3875 error ("void value not ignored as it ought to be");
3876 return error_mark_node;
3877 }
3878 /* A type converts to a reference to it.
3879 This code doesn't fully support references, it's just for the
3880 special case of va_start and va_copy. */
3881 if (codel == REFERENCE_TYPE
3882 && comptypes (TREE_TYPE (type), TREE_TYPE (rhs)) == 1)
3883 {
3884 if (!lvalue_p (rhs))
3885 {
3886 error ("cannot pass rvalue to reference parameter");
3887 return error_mark_node;
3888 }
3889 if (!c_mark_addressable (rhs))
3890 return error_mark_node;
3891 rhs = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (rhs)), rhs);
3892
3893 /* We already know that these two types are compatible, but they
3894 may not be exactly identical. In fact, `TREE_TYPE (type)' is
3895 likely to be __builtin_va_list and `TREE_TYPE (rhs)' is
3896 likely to be va_list, a typedef to __builtin_va_list, which
3897 is different enough that it will cause problems later. */
3898 if (TREE_TYPE (TREE_TYPE (rhs)) != TREE_TYPE (type))
3899 rhs = build1 (NOP_EXPR, build_pointer_type (TREE_TYPE (type)), rhs);
3900
3901 rhs = build1 (NOP_EXPR, type, rhs);
3902 return rhs;
3903 }
3904 /* Some types can interconvert without explicit casts. */
3905 else if (codel == VECTOR_TYPE && coder == VECTOR_TYPE
3906 && vector_types_convertible_p (type, TREE_TYPE (rhs), true))
3907 return convert (type, rhs);
3908 /* Arithmetic types all interconvert, and enum is treated like int. */
3909 else if ((codel == INTEGER_TYPE || codel == REAL_TYPE
3910 || codel == ENUMERAL_TYPE || codel == COMPLEX_TYPE
3911 || codel == BOOLEAN_TYPE)
3912 && (coder == INTEGER_TYPE || coder == REAL_TYPE
3913 || coder == ENUMERAL_TYPE || coder == COMPLEX_TYPE
3914 || coder == BOOLEAN_TYPE))
3915 return convert_and_check (type, rhs);
3916
3917 /* Aggregates in different TUs might need conversion. */
3918 if ((codel == RECORD_TYPE || codel == UNION_TYPE)
3919 && codel == coder
3920 && comptypes (type, rhstype))
3921 return convert_and_check (type, rhs);
3922
3923 /* Conversion to a transparent union from its member types.
3924 This applies only to function arguments. */
3925 if (codel == UNION_TYPE && TYPE_TRANSPARENT_UNION (type)
3926 && (errtype == ic_argpass || errtype == ic_argpass_nonproto))
3927 {
3928 tree memb, marginal_memb = NULL_TREE;
3929
3930 for (memb = TYPE_FIELDS (type); memb ; memb = TREE_CHAIN (memb))
3931 {
3932 tree memb_type = TREE_TYPE (memb);
3933
3934 if (comptypes (TYPE_MAIN_VARIANT (memb_type),
3935 TYPE_MAIN_VARIANT (rhstype)))
3936 break;
3937
3938 if (TREE_CODE (memb_type) != POINTER_TYPE)
3939 continue;
3940
3941 if (coder == POINTER_TYPE)
3942 {
3943 tree ttl = TREE_TYPE (memb_type);
3944 tree ttr = TREE_TYPE (rhstype);
3945
3946 /* Any non-function converts to a [const][volatile] void *
3947 and vice versa; otherwise, targets must be the same.
3948 Meanwhile, the lhs target must have all the qualifiers of
3949 the rhs. */
3950 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
3951 || comp_target_types (memb_type, rhstype))
3952 {
3953 /* If this type won't generate any warnings, use it. */
3954 if (TYPE_QUALS (ttl) == TYPE_QUALS (ttr)
3955 || ((TREE_CODE (ttr) == FUNCTION_TYPE
3956 && TREE_CODE (ttl) == FUNCTION_TYPE)
3957 ? ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3958 == TYPE_QUALS (ttr))
3959 : ((TYPE_QUALS (ttl) | TYPE_QUALS (ttr))
3960 == TYPE_QUALS (ttl))))
3961 break;
3962
3963 /* Keep looking for a better type, but remember this one. */
3964 if (!marginal_memb)
3965 marginal_memb = memb;
3966 }
3967 }
3968
3969 /* Can convert integer zero to any pointer type. */
3970 if (null_pointer_constant_p (rhs))
3971 {
3972 rhs = null_pointer_node;
3973 break;
3974 }
3975 }
3976
3977 if (memb || marginal_memb)
3978 {
3979 if (!memb)
3980 {
3981 /* We have only a marginally acceptable member type;
3982 it needs a warning. */
3983 tree ttl = TREE_TYPE (TREE_TYPE (marginal_memb));
3984 tree ttr = TREE_TYPE (rhstype);
3985
3986 /* Const and volatile mean something different for function
3987 types, so the usual warnings are not appropriate. */
3988 if (TREE_CODE (ttr) == FUNCTION_TYPE
3989 && TREE_CODE (ttl) == FUNCTION_TYPE)
3990 {
3991 /* Because const and volatile on functions are
3992 restrictions that say the function will not do
3993 certain things, it is okay to use a const or volatile
3994 function where an ordinary one is wanted, but not
3995 vice-versa. */
3996 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
3997 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE "
3998 "makes qualified function "
3999 "pointer from unqualified"),
4000 G_("assignment makes qualified "
4001 "function pointer from "
4002 "unqualified"),
4003 G_("initialization makes qualified "
4004 "function pointer from "
4005 "unqualified"),
4006 G_("return makes qualified function "
4007 "pointer from unqualified"));
4008 }
4009 else if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4010 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
4011 "qualifiers from pointer target type"),
4012 G_("assignment discards qualifiers "
4013 "from pointer target type"),
4014 G_("initialization discards qualifiers "
4015 "from pointer target type"),
4016 G_("return discards qualifiers from "
4017 "pointer target type"));
4018
4019 memb = marginal_memb;
4020 }
4021
4022 if (pedantic && (!fundecl || !DECL_IN_SYSTEM_HEADER (fundecl)))
4023 pedwarn ("ISO C prohibits argument conversion to union type");
4024
4025 return build_constructor_single (type, memb, rhs);
4026 }
4027 }
4028
4029 /* Conversions among pointers */
4030 else if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
4031 && (coder == codel))
4032 {
4033 tree ttl = TREE_TYPE (type);
4034 tree ttr = TREE_TYPE (rhstype);
4035 tree mvl = ttl;
4036 tree mvr = ttr;
4037 bool is_opaque_pointer;
4038 int target_cmp = 0; /* Cache comp_target_types () result. */
4039
4040 if (TREE_CODE (mvl) != ARRAY_TYPE)
4041 mvl = TYPE_MAIN_VARIANT (mvl);
4042 if (TREE_CODE (mvr) != ARRAY_TYPE)
4043 mvr = TYPE_MAIN_VARIANT (mvr);
4044 /* Opaque pointers are treated like void pointers. */
4045 is_opaque_pointer = (targetm.vector_opaque_p (type)
4046 || targetm.vector_opaque_p (rhstype))
4047 && TREE_CODE (ttl) == VECTOR_TYPE
4048 && TREE_CODE (ttr) == VECTOR_TYPE;
4049
4050 /* C++ does not allow the implicit conversion void* -> T*. However,
4051 for the purpose of reducing the number of false positives, we
4052 tolerate the special case of
4053
4054 int *p = NULL;
4055
4056 where NULL is typically defined in C to be '(void *) 0'. */
4057 if (VOID_TYPE_P (ttr) && rhs != null_pointer_node && !VOID_TYPE_P (ttl))
4058 warning (OPT_Wc___compat, "request for implicit conversion from "
4059 "%qT to %qT not permitted in C++", rhstype, type);
4060
4061 /* Check if the right-hand side has a format attribute but the
4062 left-hand side doesn't. */
4063 if (warn_missing_format_attribute
4064 && check_missing_format_attribute (type, rhstype))
4065 {
4066 switch (errtype)
4067 {
4068 case ic_argpass:
4069 case ic_argpass_nonproto:
4070 warning (OPT_Wmissing_format_attribute,
4071 "argument %d of %qE might be "
4072 "a candidate for a format attribute",
4073 parmnum, rname);
4074 break;
4075 case ic_assign:
4076 warning (OPT_Wmissing_format_attribute,
4077 "assignment left-hand side might be "
4078 "a candidate for a format attribute");
4079 break;
4080 case ic_init:
4081 warning (OPT_Wmissing_format_attribute,
4082 "initialization left-hand side might be "
4083 "a candidate for a format attribute");
4084 break;
4085 case ic_return:
4086 warning (OPT_Wmissing_format_attribute,
4087 "return type might be "
4088 "a candidate for a format attribute");
4089 break;
4090 default:
4091 gcc_unreachable ();
4092 }
4093 }
4094
4095 /* Any non-function converts to a [const][volatile] void *
4096 and vice versa; otherwise, targets must be the same.
4097 Meanwhile, the lhs target must have all the qualifiers of the rhs. */
4098 if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4099 || (target_cmp = comp_target_types (type, rhstype))
4100 || is_opaque_pointer
4101 || (c_common_unsigned_type (mvl)
4102 == c_common_unsigned_type (mvr)))
4103 {
4104 if (pedantic
4105 && ((VOID_TYPE_P (ttl) && TREE_CODE (ttr) == FUNCTION_TYPE)
4106 ||
4107 (VOID_TYPE_P (ttr)
4108 && !null_pointer_constant_p (rhs)
4109 && TREE_CODE (ttl) == FUNCTION_TYPE)))
4110 WARN_FOR_ASSIGNMENT (G_("ISO C forbids passing argument %d of "
4111 "%qE between function pointer "
4112 "and %<void *%>"),
4113 G_("ISO C forbids assignment between "
4114 "function pointer and %<void *%>"),
4115 G_("ISO C forbids initialization between "
4116 "function pointer and %<void *%>"),
4117 G_("ISO C forbids return between function "
4118 "pointer and %<void *%>"));
4119 /* Const and volatile mean something different for function types,
4120 so the usual warnings are not appropriate. */
4121 else if (TREE_CODE (ttr) != FUNCTION_TYPE
4122 && TREE_CODE (ttl) != FUNCTION_TYPE)
4123 {
4124 if (TYPE_QUALS (ttr) & ~TYPE_QUALS (ttl))
4125 {
4126 /* Types differing only by the presence of the 'volatile'
4127 qualifier are acceptable if the 'volatile' has been added
4128 in by the Objective-C EH machinery. */
4129 if (!objc_type_quals_match (ttl, ttr))
4130 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE discards "
4131 "qualifiers from pointer target type"),
4132 G_("assignment discards qualifiers "
4133 "from pointer target type"),
4134 G_("initialization discards qualifiers "
4135 "from pointer target type"),
4136 G_("return discards qualifiers from "
4137 "pointer target type"));
4138 }
4139 /* If this is not a case of ignoring a mismatch in signedness,
4140 no warning. */
4141 else if (VOID_TYPE_P (ttl) || VOID_TYPE_P (ttr)
4142 || target_cmp)
4143 ;
4144 /* If there is a mismatch, do warn. */
4145 else if (warn_pointer_sign)
4146 WARN_FOR_ASSIGNMENT (G_("pointer targets in passing argument "
4147 "%d of %qE differ in signedness"),
4148 G_("pointer targets in assignment "
4149 "differ in signedness"),
4150 G_("pointer targets in initialization "
4151 "differ in signedness"),
4152 G_("pointer targets in return differ "
4153 "in signedness"));
4154 }
4155 else if (TREE_CODE (ttl) == FUNCTION_TYPE
4156 && TREE_CODE (ttr) == FUNCTION_TYPE)
4157 {
4158 /* Because const and volatile on functions are restrictions
4159 that say the function will not do certain things,
4160 it is okay to use a const or volatile function
4161 where an ordinary one is wanted, but not vice-versa. */
4162 if (TYPE_QUALS (ttl) & ~TYPE_QUALS (ttr))
4163 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
4164 "qualified function pointer "
4165 "from unqualified"),
4166 G_("assignment makes qualified function "
4167 "pointer from unqualified"),
4168 G_("initialization makes qualified "
4169 "function pointer from unqualified"),
4170 G_("return makes qualified function "
4171 "pointer from unqualified"));
4172 }
4173 }
4174 else
4175 /* Avoid warning about the volatile ObjC EH puts on decls. */
4176 if (!objc_ok)
4177 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE from "
4178 "incompatible pointer type"),
4179 G_("assignment from incompatible pointer type"),
4180 G_("initialization from incompatible "
4181 "pointer type"),
4182 G_("return from incompatible pointer type"));
4183
4184 return convert (type, rhs);
4185 }
4186 else if (codel == POINTER_TYPE && coder == ARRAY_TYPE)
4187 {
4188 /* ??? This should not be an error when inlining calls to
4189 unprototyped functions. */
4190 error ("invalid use of non-lvalue array");
4191 return error_mark_node;
4192 }
4193 else if (codel == POINTER_TYPE && coder == INTEGER_TYPE)
4194 {
4195 /* An explicit constant 0 can convert to a pointer,
4196 or one that results from arithmetic, even including
4197 a cast to integer type. */
4198 if (!null_pointer_constant_p (rhs))
4199 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes "
4200 "pointer from integer without a cast"),
4201 G_("assignment makes pointer from integer "
4202 "without a cast"),
4203 G_("initialization makes pointer from "
4204 "integer without a cast"),
4205 G_("return makes pointer from integer "
4206 "without a cast"));
4207
4208 return convert (type, rhs);
4209 }
4210 else if (codel == INTEGER_TYPE && coder == POINTER_TYPE)
4211 {
4212 WARN_FOR_ASSIGNMENT (G_("passing argument %d of %qE makes integer "
4213 "from pointer without a cast"),
4214 G_("assignment makes integer from pointer "
4215 "without a cast"),
4216 G_("initialization makes integer from pointer "
4217 "without a cast"),
4218 G_("return makes integer from pointer "
4219 "without a cast"));
4220 return convert (type, rhs);
4221 }
4222 else if (codel == BOOLEAN_TYPE && coder == POINTER_TYPE)
4223 return convert (type, rhs);
4224
4225 switch (errtype)
4226 {
4227 case ic_argpass:
4228 case ic_argpass_nonproto:
4229 /* ??? This should not be an error when inlining calls to
4230 unprototyped functions. */
4231 error ("incompatible type for argument %d of %qE", parmnum, rname);
4232 break;
4233 case ic_assign:
4234 error ("incompatible types in assignment");
4235 break;
4236 case ic_init:
4237 error ("incompatible types in initialization");
4238 break;
4239 case ic_return:
4240 error ("incompatible types in return");
4241 break;
4242 default:
4243 gcc_unreachable ();
4244 }
4245
4246 return error_mark_node;
4247 }
4248
4249 /* Convert VALUE for assignment into inlined parameter PARM. ARGNUM
4250 is used for error and warning reporting and indicates which argument
4251 is being processed. */
4252
4253 tree
c_convert_parm_for_inlining(tree parm,tree value,tree fn,int argnum)4254 c_convert_parm_for_inlining (tree parm, tree value, tree fn, int argnum)
4255 {
4256 tree ret, type;
4257
4258 /* If FN was prototyped at the call site, the value has been converted
4259 already in convert_arguments.
4260 However, we might see a prototype now that was not in place when
4261 the function call was seen, so check that the VALUE actually matches
4262 PARM before taking an early exit. */
4263 if (!value
4264 || (TYPE_ARG_TYPES (TREE_TYPE (fn))
4265 && (TYPE_MAIN_VARIANT (TREE_TYPE (parm))
4266 == TYPE_MAIN_VARIANT (TREE_TYPE (value)))))
4267 return value;
4268
4269 type = TREE_TYPE (parm);
4270 ret = convert_for_assignment (type, value,
4271 ic_argpass_nonproto, fn,
4272 fn, argnum);
4273 if (targetm.calls.promote_prototypes (TREE_TYPE (fn))
4274 && INTEGRAL_TYPE_P (type)
4275 && (TYPE_PRECISION (type) < TYPE_PRECISION (integer_type_node)))
4276 ret = default_conversion (ret);
4277 return ret;
4278 }
4279
4280 /* If VALUE is a compound expr all of whose expressions are constant, then
4281 return its value. Otherwise, return error_mark_node.
4282
4283 This is for handling COMPOUND_EXPRs as initializer elements
4284 which is allowed with a warning when -pedantic is specified. */
4285
4286 static tree
valid_compound_expr_initializer(tree value,tree endtype)4287 valid_compound_expr_initializer (tree value, tree endtype)
4288 {
4289 if (TREE_CODE (value) == COMPOUND_EXPR)
4290 {
4291 if (valid_compound_expr_initializer (TREE_OPERAND (value, 0), endtype)
4292 == error_mark_node)
4293 return error_mark_node;
4294 return valid_compound_expr_initializer (TREE_OPERAND (value, 1),
4295 endtype);
4296 }
4297 else if (!initializer_constant_valid_p (value, endtype))
4298 return error_mark_node;
4299 else
4300 return value;
4301 }
4302
4303 /* Perform appropriate conversions on the initial value of a variable,
4304 store it in the declaration DECL,
4305 and print any error messages that are appropriate.
4306 If the init is invalid, store an ERROR_MARK. */
4307
4308 void
store_init_value(tree decl,tree init)4309 store_init_value (tree decl, tree init)
4310 {
4311 tree value, type;
4312
4313 /* If variable's type was invalidly declared, just ignore it. */
4314
4315 type = TREE_TYPE (decl);
4316 if (TREE_CODE (type) == ERROR_MARK)
4317 return;
4318
4319 /* Digest the specified initializer into an expression. */
4320
4321 value = digest_init (type, init, true, TREE_STATIC (decl));
4322
4323 /* Store the expression if valid; else report error. */
4324
4325 if (!in_system_header
4326 && AGGREGATE_TYPE_P (TREE_TYPE (decl)) && !TREE_STATIC (decl))
4327 warning (OPT_Wtraditional, "traditional C rejects automatic "
4328 "aggregate initialization");
4329
4330 DECL_INITIAL (decl) = value;
4331
4332 /* ANSI wants warnings about out-of-range constant initializers. */
4333 STRIP_TYPE_NOPS (value);
4334 constant_expression_warning (value);
4335
4336 /* Check if we need to set array size from compound literal size. */
4337 if (TREE_CODE (type) == ARRAY_TYPE
4338 && TYPE_DOMAIN (type) == 0
4339 && value != error_mark_node)
4340 {
4341 tree inside_init = init;
4342
4343 STRIP_TYPE_NOPS (inside_init);
4344 inside_init = fold (inside_init);
4345
4346 if (TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4347 {
4348 tree cldecl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4349
4350 if (TYPE_DOMAIN (TREE_TYPE (cldecl)))
4351 {
4352 /* For int foo[] = (int [3]){1}; we need to set array size
4353 now since later on array initializer will be just the
4354 brace enclosed list of the compound literal. */
4355 type = build_distinct_type_copy (TYPE_MAIN_VARIANT (type));
4356 TREE_TYPE (decl) = type;
4357 TYPE_DOMAIN (type) = TYPE_DOMAIN (TREE_TYPE (cldecl));
4358 layout_type (type);
4359 layout_decl (cldecl, 0);
4360 }
4361 }
4362 }
4363 }
4364
4365 /* Methods for storing and printing names for error messages. */
4366
4367 /* Implement a spelling stack that allows components of a name to be pushed
4368 and popped. Each element on the stack is this structure. */
4369
4370 struct spelling
4371 {
4372 int kind;
4373 union
4374 {
4375 unsigned HOST_WIDE_INT i;
4376 const char *s;
4377 } u;
4378 };
4379
4380 #define SPELLING_STRING 1
4381 #define SPELLING_MEMBER 2
4382 #define SPELLING_BOUNDS 3
4383
4384 static struct spelling *spelling; /* Next stack element (unused). */
4385 static struct spelling *spelling_base; /* Spelling stack base. */
4386 static int spelling_size; /* Size of the spelling stack. */
4387
4388 /* Macros to save and restore the spelling stack around push_... functions.
4389 Alternative to SAVE_SPELLING_STACK. */
4390
4391 #define SPELLING_DEPTH() (spelling - spelling_base)
4392 #define RESTORE_SPELLING_DEPTH(DEPTH) (spelling = spelling_base + (DEPTH))
4393
4394 /* Push an element on the spelling stack with type KIND and assign VALUE
4395 to MEMBER. */
4396
4397 #define PUSH_SPELLING(KIND, VALUE, MEMBER) \
4398 { \
4399 int depth = SPELLING_DEPTH (); \
4400 \
4401 if (depth >= spelling_size) \
4402 { \
4403 spelling_size += 10; \
4404 spelling_base = XRESIZEVEC (struct spelling, spelling_base, \
4405 spelling_size); \
4406 RESTORE_SPELLING_DEPTH (depth); \
4407 } \
4408 \
4409 spelling->kind = (KIND); \
4410 spelling->MEMBER = (VALUE); \
4411 spelling++; \
4412 }
4413
4414 /* Push STRING on the stack. Printed literally. */
4415
4416 static void
push_string(const char * string)4417 push_string (const char *string)
4418 {
4419 PUSH_SPELLING (SPELLING_STRING, string, u.s);
4420 }
4421
4422 /* Push a member name on the stack. Printed as '.' STRING. */
4423
4424 static void
push_member_name(tree decl)4425 push_member_name (tree decl)
4426 {
4427 const char *const string
4428 = DECL_NAME (decl) ? IDENTIFIER_POINTER (DECL_NAME (decl)) : "<anonymous>";
4429 PUSH_SPELLING (SPELLING_MEMBER, string, u.s);
4430 }
4431
4432 /* Push an array bounds on the stack. Printed as [BOUNDS]. */
4433
4434 static void
push_array_bounds(unsigned HOST_WIDE_INT bounds)4435 push_array_bounds (unsigned HOST_WIDE_INT bounds)
4436 {
4437 PUSH_SPELLING (SPELLING_BOUNDS, bounds, u.i);
4438 }
4439
4440 /* Compute the maximum size in bytes of the printed spelling. */
4441
4442 static int
spelling_length(void)4443 spelling_length (void)
4444 {
4445 int size = 0;
4446 struct spelling *p;
4447
4448 for (p = spelling_base; p < spelling; p++)
4449 {
4450 if (p->kind == SPELLING_BOUNDS)
4451 size += 25;
4452 else
4453 size += strlen (p->u.s) + 1;
4454 }
4455
4456 return size;
4457 }
4458
4459 /* Print the spelling to BUFFER and return it. */
4460
4461 static char *
print_spelling(char * buffer)4462 print_spelling (char *buffer)
4463 {
4464 char *d = buffer;
4465 struct spelling *p;
4466
4467 for (p = spelling_base; p < spelling; p++)
4468 if (p->kind == SPELLING_BOUNDS)
4469 {
4470 sprintf (d, "[" HOST_WIDE_INT_PRINT_UNSIGNED "]", p->u.i);
4471 d += strlen (d);
4472 }
4473 else
4474 {
4475 const char *s;
4476 if (p->kind == SPELLING_MEMBER)
4477 *d++ = '.';
4478 for (s = p->u.s; (*d = *s++); d++)
4479 ;
4480 }
4481 *d++ = '\0';
4482 return buffer;
4483 }
4484
4485 /* Issue an error message for a bad initializer component.
4486 MSGID identifies the message.
4487 The component name is taken from the spelling stack. */
4488
4489 void
error_init(const char * msgid)4490 error_init (const char *msgid)
4491 {
4492 char *ofwhat;
4493
4494 error ("%s", _(msgid));
4495 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4496 if (*ofwhat)
4497 error ("(near initialization for %qs)", ofwhat);
4498 }
4499
4500 /* Issue a pedantic warning for a bad initializer component.
4501 MSGID identifies the message.
4502 The component name is taken from the spelling stack. */
4503
4504 void
pedwarn_init(const char * msgid)4505 pedwarn_init (const char *msgid)
4506 {
4507 char *ofwhat;
4508
4509 pedwarn ("%s", _(msgid));
4510 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4511 if (*ofwhat)
4512 pedwarn ("(near initialization for %qs)", ofwhat);
4513 }
4514
4515 /* Issue a warning for a bad initializer component.
4516 MSGID identifies the message.
4517 The component name is taken from the spelling stack. */
4518
4519 static void
warning_init(const char * msgid)4520 warning_init (const char *msgid)
4521 {
4522 char *ofwhat;
4523
4524 warning (0, "%s", _(msgid));
4525 ofwhat = print_spelling ((char *) alloca (spelling_length () + 1));
4526 if (*ofwhat)
4527 warning (0, "(near initialization for %qs)", ofwhat);
4528 }
4529
4530 /* If TYPE is an array type and EXPR is a parenthesized string
4531 constant, warn if pedantic that EXPR is being used to initialize an
4532 object of type TYPE. */
4533
4534 void
maybe_warn_string_init(tree type,struct c_expr expr)4535 maybe_warn_string_init (tree type, struct c_expr expr)
4536 {
4537 if (pedantic
4538 && TREE_CODE (type) == ARRAY_TYPE
4539 && TREE_CODE (expr.value) == STRING_CST
4540 && expr.original_code != STRING_CST)
4541 pedwarn_init ("array initialized from parenthesized string constant");
4542 }
4543
4544 /* Digest the parser output INIT as an initializer for type TYPE.
4545 Return a C expression of type TYPE to represent the initial value.
4546
4547 If INIT is a string constant, STRICT_STRING is true if it is
4548 unparenthesized or we should not warn here for it being parenthesized.
4549 For other types of INIT, STRICT_STRING is not used.
4550
4551 REQUIRE_CONSTANT requests an error if non-constant initializers or
4552 elements are seen. */
4553
4554 static tree
digest_init(tree type,tree init,bool strict_string,int require_constant)4555 digest_init (tree type, tree init, bool strict_string, int require_constant)
4556 {
4557 enum tree_code code = TREE_CODE (type);
4558 tree inside_init = init;
4559
4560 if (type == error_mark_node
4561 || !init
4562 || init == error_mark_node
4563 || TREE_TYPE (init) == error_mark_node)
4564 return error_mark_node;
4565
4566 STRIP_TYPE_NOPS (inside_init);
4567
4568 inside_init = fold (inside_init);
4569
4570 /* Initialization of an array of chars from a string constant
4571 optionally enclosed in braces. */
4572
4573 if (code == ARRAY_TYPE && inside_init
4574 && TREE_CODE (inside_init) == STRING_CST)
4575 {
4576 tree typ1 = TYPE_MAIN_VARIANT (TREE_TYPE (type));
4577 /* Note that an array could be both an array of character type
4578 and an array of wchar_t if wchar_t is signed char or unsigned
4579 char. */
4580 bool char_array = (typ1 == char_type_node
4581 || typ1 == signed_char_type_node
4582 || typ1 == unsigned_char_type_node);
4583 bool wchar_array = !!comptypes (typ1, wchar_type_node);
4584 if (char_array || wchar_array)
4585 {
4586 struct c_expr expr;
4587 bool char_string;
4588 expr.value = inside_init;
4589 expr.original_code = (strict_string ? STRING_CST : ERROR_MARK);
4590 maybe_warn_string_init (type, expr);
4591
4592 char_string
4593 = (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (inside_init)))
4594 == char_type_node);
4595
4596 if (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4597 TYPE_MAIN_VARIANT (type)))
4598 return inside_init;
4599
4600 if (!wchar_array && !char_string)
4601 {
4602 error_init ("char-array initialized from wide string");
4603 return error_mark_node;
4604 }
4605 if (char_string && !char_array)
4606 {
4607 error_init ("wchar_t-array initialized from non-wide string");
4608 return error_mark_node;
4609 }
4610
4611 TREE_TYPE (inside_init) = type;
4612 if (TYPE_DOMAIN (type) != 0
4613 && TYPE_SIZE (type) != 0
4614 && TREE_CODE (TYPE_SIZE (type)) == INTEGER_CST
4615 /* Subtract 1 (or sizeof (wchar_t))
4616 because it's ok to ignore the terminating null char
4617 that is counted in the length of the constant. */
4618 && 0 > compare_tree_int (TYPE_SIZE_UNIT (type),
4619 TREE_STRING_LENGTH (inside_init)
4620 - ((TYPE_PRECISION (typ1)
4621 != TYPE_PRECISION (char_type_node))
4622 ? (TYPE_PRECISION (wchar_type_node)
4623 / BITS_PER_UNIT)
4624 : 1)))
4625 pedwarn_init ("initializer-string for array of chars is too long");
4626
4627 return inside_init;
4628 }
4629 else if (INTEGRAL_TYPE_P (typ1))
4630 {
4631 error_init ("array of inappropriate type initialized "
4632 "from string constant");
4633 return error_mark_node;
4634 }
4635 }
4636
4637 /* Build a VECTOR_CST from a *constant* vector constructor. If the
4638 vector constructor is not constant (e.g. {1,2,3,foo()}) then punt
4639 below and handle as a constructor. */
4640 if (code == VECTOR_TYPE
4641 && TREE_CODE (TREE_TYPE (inside_init)) == VECTOR_TYPE
4642 && vector_types_convertible_p (TREE_TYPE (inside_init), type, true)
4643 && TREE_CONSTANT (inside_init))
4644 {
4645 if (TREE_CODE (inside_init) == VECTOR_CST
4646 && comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4647 TYPE_MAIN_VARIANT (type)))
4648 return inside_init;
4649
4650 if (TREE_CODE (inside_init) == CONSTRUCTOR)
4651 {
4652 unsigned HOST_WIDE_INT ix;
4653 tree value;
4654 bool constant_p = true;
4655
4656 /* Iterate through elements and check if all constructor
4657 elements are *_CSTs. */
4658 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (inside_init), ix, value)
4659 if (!CONSTANT_CLASS_P (value))
4660 {
4661 constant_p = false;
4662 break;
4663 }
4664
4665 if (constant_p)
4666 return build_vector_from_ctor (type,
4667 CONSTRUCTOR_ELTS (inside_init));
4668 }
4669 }
4670
4671 /* Any type can be initialized
4672 from an expression of the same type, optionally with braces. */
4673
4674 if (inside_init && TREE_TYPE (inside_init) != 0
4675 && (comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (inside_init)),
4676 TYPE_MAIN_VARIANT (type))
4677 || (code == ARRAY_TYPE
4678 && comptypes (TREE_TYPE (inside_init), type))
4679 || (code == VECTOR_TYPE
4680 && comptypes (TREE_TYPE (inside_init), type))
4681 || (code == POINTER_TYPE
4682 && TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE
4683 && comptypes (TREE_TYPE (TREE_TYPE (inside_init)),
4684 TREE_TYPE (type)))))
4685 {
4686 if (code == POINTER_TYPE)
4687 {
4688 if (TREE_CODE (TREE_TYPE (inside_init)) == ARRAY_TYPE)
4689 {
4690 if (TREE_CODE (inside_init) == STRING_CST
4691 || TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4692 inside_init = array_to_pointer_conversion (inside_init);
4693 else
4694 {
4695 error_init ("invalid use of non-lvalue array");
4696 return error_mark_node;
4697 }
4698 }
4699 }
4700
4701 if (code == VECTOR_TYPE)
4702 /* Although the types are compatible, we may require a
4703 conversion. */
4704 inside_init = convert (type, inside_init);
4705
4706 if (require_constant
4707 && (code == VECTOR_TYPE || !flag_isoc99)
4708 && TREE_CODE (inside_init) == COMPOUND_LITERAL_EXPR)
4709 {
4710 /* As an extension, allow initializing objects with static storage
4711 duration with compound literals (which are then treated just as
4712 the brace enclosed list they contain). Also allow this for
4713 vectors, as we can only assign them with compound literals. */
4714 tree decl = COMPOUND_LITERAL_EXPR_DECL (inside_init);
4715 inside_init = DECL_INITIAL (decl);
4716 }
4717
4718 if (code == ARRAY_TYPE && TREE_CODE (inside_init) != STRING_CST
4719 && TREE_CODE (inside_init) != CONSTRUCTOR)
4720 {
4721 error_init ("array initialized from non-constant array expression");
4722 return error_mark_node;
4723 }
4724
4725 if (optimize && TREE_CODE (inside_init) == VAR_DECL)
4726 inside_init = decl_constant_value_for_broken_optimization (inside_init);
4727
4728 /* Compound expressions can only occur here if -pedantic or
4729 -pedantic-errors is specified. In the later case, we always want
4730 an error. In the former case, we simply want a warning. */
4731 if (require_constant && pedantic
4732 && TREE_CODE (inside_init) == COMPOUND_EXPR)
4733 {
4734 inside_init
4735 = valid_compound_expr_initializer (inside_init,
4736 TREE_TYPE (inside_init));
4737 if (inside_init == error_mark_node)
4738 error_init ("initializer element is not constant");
4739 else
4740 pedwarn_init ("initializer element is not constant");
4741 if (flag_pedantic_errors)
4742 inside_init = error_mark_node;
4743 }
4744 else if (require_constant
4745 && !initializer_constant_valid_p (inside_init,
4746 TREE_TYPE (inside_init)))
4747 {
4748 error_init ("initializer element is not constant");
4749 inside_init = error_mark_node;
4750 }
4751
4752 /* Added to enable additional -Wmissing-format-attribute warnings. */
4753 if (TREE_CODE (TREE_TYPE (inside_init)) == POINTER_TYPE)
4754 inside_init = convert_for_assignment (type, inside_init, ic_init, NULL_TREE,
4755 NULL_TREE, 0);
4756 return inside_init;
4757 }
4758
4759 /* Handle scalar types, including conversions. */
4760
4761 if (code == INTEGER_TYPE || code == REAL_TYPE || code == POINTER_TYPE
4762 || code == ENUMERAL_TYPE || code == BOOLEAN_TYPE || code == COMPLEX_TYPE
4763 || code == VECTOR_TYPE)
4764 {
4765 if (TREE_CODE (TREE_TYPE (init)) == ARRAY_TYPE
4766 && (TREE_CODE (init) == STRING_CST
4767 || TREE_CODE (init) == COMPOUND_LITERAL_EXPR))
4768 init = array_to_pointer_conversion (init);
4769 inside_init
4770 = convert_for_assignment (type, init, ic_init,
4771 NULL_TREE, NULL_TREE, 0);
4772
4773 /* Check to see if we have already given an error message. */
4774 if (inside_init == error_mark_node)
4775 ;
4776 else if (require_constant && !TREE_CONSTANT (inside_init))
4777 {
4778 error_init ("initializer element is not constant");
4779 inside_init = error_mark_node;
4780 }
4781 else if (require_constant
4782 && !initializer_constant_valid_p (inside_init,
4783 TREE_TYPE (inside_init)))
4784 {
4785 error_init ("initializer element is not computable at load time");
4786 inside_init = error_mark_node;
4787 }
4788
4789 return inside_init;
4790 }
4791
4792 /* Come here only for records and arrays. */
4793
4794 if (COMPLETE_TYPE_P (type) && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
4795 {
4796 error_init ("variable-sized object may not be initialized");
4797 return error_mark_node;
4798 }
4799
4800 error_init ("invalid initializer");
4801 return error_mark_node;
4802 }
4803
4804 /* Handle initializers that use braces. */
4805
4806 /* Type of object we are accumulating a constructor for.
4807 This type is always a RECORD_TYPE, UNION_TYPE or ARRAY_TYPE. */
4808 static tree constructor_type;
4809
4810 /* For a RECORD_TYPE or UNION_TYPE, this is the chain of fields
4811 left to fill. */
4812 static tree constructor_fields;
4813
4814 /* For an ARRAY_TYPE, this is the specified index
4815 at which to store the next element we get. */
4816 static tree constructor_index;
4817
4818 /* For an ARRAY_TYPE, this is the maximum index. */
4819 static tree constructor_max_index;
4820
4821 /* For a RECORD_TYPE, this is the first field not yet written out. */
4822 static tree constructor_unfilled_fields;
4823
4824 /* For an ARRAY_TYPE, this is the index of the first element
4825 not yet written out. */
4826 static tree constructor_unfilled_index;
4827
4828 /* In a RECORD_TYPE, the byte index of the next consecutive field.
4829 This is so we can generate gaps between fields, when appropriate. */
4830 static tree constructor_bit_index;
4831
4832 /* If we are saving up the elements rather than allocating them,
4833 this is the list of elements so far (in reverse order,
4834 most recent first). */
4835 static VEC(constructor_elt,gc) *constructor_elements;
4836
4837 /* 1 if constructor should be incrementally stored into a constructor chain,
4838 0 if all the elements should be kept in AVL tree. */
4839 static int constructor_incremental;
4840
4841 /* 1 if so far this constructor's elements are all compile-time constants. */
4842 static int constructor_constant;
4843
4844 /* 1 if so far this constructor's elements are all valid address constants. */
4845 static int constructor_simple;
4846
4847 /* 1 if this constructor is erroneous so far. */
4848 static int constructor_erroneous;
4849
4850 /* Structure for managing pending initializer elements, organized as an
4851 AVL tree. */
4852
4853 struct init_node
4854 {
4855 struct init_node *left, *right;
4856 struct init_node *parent;
4857 int balance;
4858 tree purpose;
4859 tree value;
4860 };
4861
4862 /* Tree of pending elements at this constructor level.
4863 These are elements encountered out of order
4864 which belong at places we haven't reached yet in actually
4865 writing the output.
4866 Will never hold tree nodes across GC runs. */
4867 static struct init_node *constructor_pending_elts;
4868
4869 /* The SPELLING_DEPTH of this constructor. */
4870 static int constructor_depth;
4871
4872 /* DECL node for which an initializer is being read.
4873 0 means we are reading a constructor expression
4874 such as (struct foo) {...}. */
4875 static tree constructor_decl;
4876
4877 /* Nonzero if this is an initializer for a top-level decl. */
4878 static int constructor_top_level;
4879
4880 /* Nonzero if there were any member designators in this initializer. */
4881 static int constructor_designated;
4882
4883 /* Nesting depth of designator list. */
4884 static int designator_depth;
4885
4886 /* Nonzero if there were diagnosed errors in this designator list. */
4887 static int designator_erroneous;
4888
4889
4890 /* This stack has a level for each implicit or explicit level of
4891 structuring in the initializer, including the outermost one. It
4892 saves the values of most of the variables above. */
4893
4894 struct constructor_range_stack;
4895
4896 struct constructor_stack
4897 {
4898 struct constructor_stack *next;
4899 tree type;
4900 tree fields;
4901 tree index;
4902 tree max_index;
4903 tree unfilled_index;
4904 tree unfilled_fields;
4905 tree bit_index;
4906 VEC(constructor_elt,gc) *elements;
4907 struct init_node *pending_elts;
4908 int offset;
4909 int depth;
4910 /* If value nonzero, this value should replace the entire
4911 constructor at this level. */
4912 struct c_expr replacement_value;
4913 struct constructor_range_stack *range_stack;
4914 char constant;
4915 char simple;
4916 char implicit;
4917 char erroneous;
4918 char outer;
4919 char incremental;
4920 char designated;
4921 };
4922
4923 static struct constructor_stack *constructor_stack;
4924
4925 /* This stack represents designators from some range designator up to
4926 the last designator in the list. */
4927
4928 struct constructor_range_stack
4929 {
4930 struct constructor_range_stack *next, *prev;
4931 struct constructor_stack *stack;
4932 tree range_start;
4933 tree index;
4934 tree range_end;
4935 tree fields;
4936 };
4937
4938 static struct constructor_range_stack *constructor_range_stack;
4939
4940 /* This stack records separate initializers that are nested.
4941 Nested initializers can't happen in ANSI C, but GNU C allows them
4942 in cases like { ... (struct foo) { ... } ... }. */
4943
4944 struct initializer_stack
4945 {
4946 struct initializer_stack *next;
4947 tree decl;
4948 struct constructor_stack *constructor_stack;
4949 struct constructor_range_stack *constructor_range_stack;
4950 VEC(constructor_elt,gc) *elements;
4951 struct spelling *spelling;
4952 struct spelling *spelling_base;
4953 int spelling_size;
4954 char top_level;
4955 char require_constant_value;
4956 char require_constant_elements;
4957 };
4958
4959 static struct initializer_stack *initializer_stack;
4960
4961 /* Prepare to parse and output the initializer for variable DECL. */
4962
4963 void
start_init(tree decl,tree asmspec_tree ATTRIBUTE_UNUSED,int top_level)4964 start_init (tree decl, tree asmspec_tree ATTRIBUTE_UNUSED, int top_level)
4965 {
4966 const char *locus;
4967 struct initializer_stack *p = XNEW (struct initializer_stack);
4968
4969 p->decl = constructor_decl;
4970 p->require_constant_value = require_constant_value;
4971 p->require_constant_elements = require_constant_elements;
4972 p->constructor_stack = constructor_stack;
4973 p->constructor_range_stack = constructor_range_stack;
4974 p->elements = constructor_elements;
4975 p->spelling = spelling;
4976 p->spelling_base = spelling_base;
4977 p->spelling_size = spelling_size;
4978 p->top_level = constructor_top_level;
4979 p->next = initializer_stack;
4980 initializer_stack = p;
4981
4982 constructor_decl = decl;
4983 constructor_designated = 0;
4984 constructor_top_level = top_level;
4985
4986 if (decl != 0 && decl != error_mark_node)
4987 {
4988 require_constant_value = TREE_STATIC (decl);
4989 require_constant_elements
4990 = ((TREE_STATIC (decl) || (pedantic && !flag_isoc99))
4991 /* For a scalar, you can always use any value to initialize,
4992 even within braces. */
4993 && (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
4994 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
4995 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
4996 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE));
4997 locus = IDENTIFIER_POINTER (DECL_NAME (decl));
4998 }
4999 else
5000 {
5001 require_constant_value = 0;
5002 require_constant_elements = 0;
5003 locus = "(anonymous)";
5004 }
5005
5006 constructor_stack = 0;
5007 constructor_range_stack = 0;
5008
5009 missing_braces_mentioned = 0;
5010
5011 spelling_base = 0;
5012 spelling_size = 0;
5013 RESTORE_SPELLING_DEPTH (0);
5014
5015 if (locus)
5016 push_string (locus);
5017 }
5018
5019 void
finish_init(void)5020 finish_init (void)
5021 {
5022 struct initializer_stack *p = initializer_stack;
5023
5024 /* Free the whole constructor stack of this initializer. */
5025 while (constructor_stack)
5026 {
5027 struct constructor_stack *q = constructor_stack;
5028 constructor_stack = q->next;
5029 free (q);
5030 }
5031
5032 gcc_assert (!constructor_range_stack);
5033
5034 /* Pop back to the data of the outer initializer (if any). */
5035 free (spelling_base);
5036
5037 constructor_decl = p->decl;
5038 require_constant_value = p->require_constant_value;
5039 require_constant_elements = p->require_constant_elements;
5040 constructor_stack = p->constructor_stack;
5041 constructor_range_stack = p->constructor_range_stack;
5042 constructor_elements = p->elements;
5043 spelling = p->spelling;
5044 spelling_base = p->spelling_base;
5045 spelling_size = p->spelling_size;
5046 constructor_top_level = p->top_level;
5047 initializer_stack = p->next;
5048 free (p);
5049 }
5050
5051 /* Call here when we see the initializer is surrounded by braces.
5052 This is instead of a call to push_init_level;
5053 it is matched by a call to pop_init_level.
5054
5055 TYPE is the type to initialize, for a constructor expression.
5056 For an initializer for a decl, TYPE is zero. */
5057
5058 void
really_start_incremental_init(tree type)5059 really_start_incremental_init (tree type)
5060 {
5061 struct constructor_stack *p = XNEW (struct constructor_stack);
5062
5063 if (type == 0)
5064 type = TREE_TYPE (constructor_decl);
5065
5066 if (targetm.vector_opaque_p (type))
5067 error ("opaque vector types cannot be initialized");
5068
5069 p->type = constructor_type;
5070 p->fields = constructor_fields;
5071 p->index = constructor_index;
5072 p->max_index = constructor_max_index;
5073 p->unfilled_index = constructor_unfilled_index;
5074 p->unfilled_fields = constructor_unfilled_fields;
5075 p->bit_index = constructor_bit_index;
5076 p->elements = constructor_elements;
5077 p->constant = constructor_constant;
5078 p->simple = constructor_simple;
5079 p->erroneous = constructor_erroneous;
5080 p->pending_elts = constructor_pending_elts;
5081 p->depth = constructor_depth;
5082 p->replacement_value.value = 0;
5083 p->replacement_value.original_code = ERROR_MARK;
5084 p->implicit = 0;
5085 p->range_stack = 0;
5086 p->outer = 0;
5087 p->incremental = constructor_incremental;
5088 p->designated = constructor_designated;
5089 p->next = 0;
5090 constructor_stack = p;
5091
5092 constructor_constant = 1;
5093 constructor_simple = 1;
5094 constructor_depth = SPELLING_DEPTH ();
5095 constructor_elements = 0;
5096 constructor_pending_elts = 0;
5097 constructor_type = type;
5098 constructor_incremental = 1;
5099 constructor_designated = 0;
5100 designator_depth = 0;
5101 designator_erroneous = 0;
5102
5103 if (TREE_CODE (constructor_type) == RECORD_TYPE
5104 || TREE_CODE (constructor_type) == UNION_TYPE)
5105 {
5106 constructor_fields = TYPE_FIELDS (constructor_type);
5107 /* Skip any nameless bit fields at the beginning. */
5108 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5109 && DECL_NAME (constructor_fields) == 0)
5110 constructor_fields = TREE_CHAIN (constructor_fields);
5111
5112 constructor_unfilled_fields = constructor_fields;
5113 constructor_bit_index = bitsize_zero_node;
5114 }
5115 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5116 {
5117 if (TYPE_DOMAIN (constructor_type))
5118 {
5119 constructor_max_index
5120 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5121
5122 /* Detect non-empty initializations of zero-length arrays. */
5123 if (constructor_max_index == NULL_TREE
5124 && TYPE_SIZE (constructor_type))
5125 constructor_max_index = build_int_cst (NULL_TREE, -1);
5126
5127 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5128 to initialize VLAs will cause a proper error; avoid tree
5129 checking errors as well by setting a safe value. */
5130 if (constructor_max_index
5131 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5132 constructor_max_index = build_int_cst (NULL_TREE, -1);
5133
5134 constructor_index
5135 = convert (bitsizetype,
5136 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5137 }
5138 else
5139 {
5140 constructor_index = bitsize_zero_node;
5141 constructor_max_index = NULL_TREE;
5142 }
5143
5144 constructor_unfilled_index = constructor_index;
5145 }
5146 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5147 {
5148 /* Vectors are like simple fixed-size arrays. */
5149 constructor_max_index =
5150 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5151 constructor_index = bitsize_zero_node;
5152 constructor_unfilled_index = constructor_index;
5153 }
5154 else
5155 {
5156 /* Handle the case of int x = {5}; */
5157 constructor_fields = constructor_type;
5158 constructor_unfilled_fields = constructor_type;
5159 }
5160 }
5161
5162 /* Push down into a subobject, for initialization.
5163 If this is for an explicit set of braces, IMPLICIT is 0.
5164 If it is because the next element belongs at a lower level,
5165 IMPLICIT is 1 (or 2 if the push is because of designator list). */
5166
5167 void
push_init_level(int implicit)5168 push_init_level (int implicit)
5169 {
5170 struct constructor_stack *p;
5171 tree value = NULL_TREE;
5172
5173 /* If we've exhausted any levels that didn't have braces,
5174 pop them now. If implicit == 1, this will have been done in
5175 process_init_element; do not repeat it here because in the case
5176 of excess initializers for an empty aggregate this leads to an
5177 infinite cycle of popping a level and immediately recreating
5178 it. */
5179 if (implicit != 1)
5180 {
5181 while (constructor_stack->implicit)
5182 {
5183 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5184 || TREE_CODE (constructor_type) == UNION_TYPE)
5185 && constructor_fields == 0)
5186 process_init_element (pop_init_level (1));
5187 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
5188 && constructor_max_index
5189 && tree_int_cst_lt (constructor_max_index,
5190 constructor_index))
5191 process_init_element (pop_init_level (1));
5192 else
5193 break;
5194 }
5195 }
5196
5197 /* Unless this is an explicit brace, we need to preserve previous
5198 content if any. */
5199 if (implicit)
5200 {
5201 if ((TREE_CODE (constructor_type) == RECORD_TYPE
5202 || TREE_CODE (constructor_type) == UNION_TYPE)
5203 && constructor_fields)
5204 value = find_init_member (constructor_fields);
5205 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5206 value = find_init_member (constructor_index);
5207 }
5208
5209 p = XNEW (struct constructor_stack);
5210 p->type = constructor_type;
5211 p->fields = constructor_fields;
5212 p->index = constructor_index;
5213 p->max_index = constructor_max_index;
5214 p->unfilled_index = constructor_unfilled_index;
5215 p->unfilled_fields = constructor_unfilled_fields;
5216 p->bit_index = constructor_bit_index;
5217 p->elements = constructor_elements;
5218 p->constant = constructor_constant;
5219 p->simple = constructor_simple;
5220 p->erroneous = constructor_erroneous;
5221 p->pending_elts = constructor_pending_elts;
5222 p->depth = constructor_depth;
5223 p->replacement_value.value = 0;
5224 p->replacement_value.original_code = ERROR_MARK;
5225 p->implicit = implicit;
5226 p->outer = 0;
5227 p->incremental = constructor_incremental;
5228 p->designated = constructor_designated;
5229 p->next = constructor_stack;
5230 p->range_stack = 0;
5231 constructor_stack = p;
5232
5233 constructor_constant = 1;
5234 constructor_simple = 1;
5235 constructor_depth = SPELLING_DEPTH ();
5236 constructor_elements = 0;
5237 constructor_incremental = 1;
5238 constructor_designated = 0;
5239 constructor_pending_elts = 0;
5240 if (!implicit)
5241 {
5242 p->range_stack = constructor_range_stack;
5243 constructor_range_stack = 0;
5244 designator_depth = 0;
5245 designator_erroneous = 0;
5246 }
5247
5248 /* Don't die if an entire brace-pair level is superfluous
5249 in the containing level. */
5250 if (constructor_type == 0)
5251 ;
5252 else if (TREE_CODE (constructor_type) == RECORD_TYPE
5253 || TREE_CODE (constructor_type) == UNION_TYPE)
5254 {
5255 /* Don't die if there are extra init elts at the end. */
5256 if (constructor_fields == 0)
5257 constructor_type = 0;
5258 else
5259 {
5260 constructor_type = TREE_TYPE (constructor_fields);
5261 push_member_name (constructor_fields);
5262 constructor_depth++;
5263 }
5264 }
5265 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5266 {
5267 constructor_type = TREE_TYPE (constructor_type);
5268 push_array_bounds (tree_low_cst (constructor_index, 1));
5269 constructor_depth++;
5270 }
5271
5272 if (constructor_type == 0)
5273 {
5274 error_init ("extra brace group at end of initializer");
5275 constructor_fields = 0;
5276 constructor_unfilled_fields = 0;
5277 return;
5278 }
5279
5280 if (value && TREE_CODE (value) == CONSTRUCTOR)
5281 {
5282 constructor_constant = TREE_CONSTANT (value);
5283 constructor_simple = TREE_STATIC (value);
5284 constructor_elements = CONSTRUCTOR_ELTS (value);
5285 if (!VEC_empty (constructor_elt, constructor_elements)
5286 && (TREE_CODE (constructor_type) == RECORD_TYPE
5287 || TREE_CODE (constructor_type) == ARRAY_TYPE))
5288 set_nonincremental_init ();
5289 }
5290
5291 if (implicit == 1 && warn_missing_braces && !missing_braces_mentioned)
5292 {
5293 missing_braces_mentioned = 1;
5294 warning_init ("missing braces around initializer");
5295 }
5296
5297 if (TREE_CODE (constructor_type) == RECORD_TYPE
5298 || TREE_CODE (constructor_type) == UNION_TYPE)
5299 {
5300 constructor_fields = TYPE_FIELDS (constructor_type);
5301 /* Skip any nameless bit fields at the beginning. */
5302 while (constructor_fields != 0 && DECL_C_BIT_FIELD (constructor_fields)
5303 && DECL_NAME (constructor_fields) == 0)
5304 constructor_fields = TREE_CHAIN (constructor_fields);
5305
5306 constructor_unfilled_fields = constructor_fields;
5307 constructor_bit_index = bitsize_zero_node;
5308 }
5309 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
5310 {
5311 /* Vectors are like simple fixed-size arrays. */
5312 constructor_max_index =
5313 build_int_cst (NULL_TREE, TYPE_VECTOR_SUBPARTS (constructor_type) - 1);
5314 constructor_index = convert (bitsizetype, integer_zero_node);
5315 constructor_unfilled_index = constructor_index;
5316 }
5317 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5318 {
5319 if (TYPE_DOMAIN (constructor_type))
5320 {
5321 constructor_max_index
5322 = TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type));
5323
5324 /* Detect non-empty initializations of zero-length arrays. */
5325 if (constructor_max_index == NULL_TREE
5326 && TYPE_SIZE (constructor_type))
5327 constructor_max_index = build_int_cst (NULL_TREE, -1);
5328
5329 /* constructor_max_index needs to be an INTEGER_CST. Attempts
5330 to initialize VLAs will cause a proper error; avoid tree
5331 checking errors as well by setting a safe value. */
5332 if (constructor_max_index
5333 && TREE_CODE (constructor_max_index) != INTEGER_CST)
5334 constructor_max_index = build_int_cst (NULL_TREE, -1);
5335
5336 constructor_index
5337 = convert (bitsizetype,
5338 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5339 }
5340 else
5341 constructor_index = bitsize_zero_node;
5342
5343 constructor_unfilled_index = constructor_index;
5344 if (value && TREE_CODE (value) == STRING_CST)
5345 {
5346 /* We need to split the char/wchar array into individual
5347 characters, so that we don't have to special case it
5348 everywhere. */
5349 set_nonincremental_init_from_string (value);
5350 }
5351 }
5352 else
5353 {
5354 if (constructor_type != error_mark_node)
5355 warning_init ("braces around scalar initializer");
5356 constructor_fields = constructor_type;
5357 constructor_unfilled_fields = constructor_type;
5358 }
5359 }
5360
5361 /* At the end of an implicit or explicit brace level,
5362 finish up that level of constructor. If a single expression
5363 with redundant braces initialized that level, return the
5364 c_expr structure for that expression. Otherwise, the original_code
5365 element is set to ERROR_MARK.
5366 If we were outputting the elements as they are read, return 0 as the value
5367 from inner levels (process_init_element ignores that),
5368 but return error_mark_node as the value from the outermost level
5369 (that's what we want to put in DECL_INITIAL).
5370 Otherwise, return a CONSTRUCTOR expression as the value. */
5371
5372 struct c_expr
pop_init_level(int implicit)5373 pop_init_level (int implicit)
5374 {
5375 struct constructor_stack *p;
5376 struct c_expr ret;
5377 ret.value = 0;
5378 ret.original_code = ERROR_MARK;
5379
5380 if (implicit == 0)
5381 {
5382 /* When we come to an explicit close brace,
5383 pop any inner levels that didn't have explicit braces. */
5384 while (constructor_stack->implicit)
5385 process_init_element (pop_init_level (1));
5386
5387 gcc_assert (!constructor_range_stack);
5388 }
5389
5390 /* Now output all pending elements. */
5391 constructor_incremental = 1;
5392 output_pending_init_elements (1);
5393
5394 p = constructor_stack;
5395
5396 /* Error for initializing a flexible array member, or a zero-length
5397 array member in an inappropriate context. */
5398 if (constructor_type && constructor_fields
5399 && TREE_CODE (constructor_type) == ARRAY_TYPE
5400 && TYPE_DOMAIN (constructor_type)
5401 && !TYPE_MAX_VALUE (TYPE_DOMAIN (constructor_type)))
5402 {
5403 /* Silently discard empty initializations. The parser will
5404 already have pedwarned for empty brackets. */
5405 if (integer_zerop (constructor_unfilled_index))
5406 constructor_type = NULL_TREE;
5407 else
5408 {
5409 gcc_assert (!TYPE_SIZE (constructor_type));
5410
5411 if (constructor_depth > 2)
5412 error_init ("initialization of flexible array member in a nested context");
5413 else if (pedantic)
5414 pedwarn_init ("initialization of a flexible array member");
5415
5416 /* We have already issued an error message for the existence
5417 of a flexible array member not at the end of the structure.
5418 Discard the initializer so that we do not die later. */
5419 if (TREE_CHAIN (constructor_fields) != NULL_TREE)
5420 constructor_type = NULL_TREE;
5421 }
5422 }
5423
5424 /* Warn when some struct elements are implicitly initialized to zero. */
5425 if (warn_missing_field_initializers
5426 && constructor_type
5427 && TREE_CODE (constructor_type) == RECORD_TYPE
5428 && constructor_unfilled_fields)
5429 {
5430 /* Do not warn for flexible array members or zero-length arrays. */
5431 while (constructor_unfilled_fields
5432 && (!DECL_SIZE (constructor_unfilled_fields)
5433 || integer_zerop (DECL_SIZE (constructor_unfilled_fields))))
5434 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5435
5436 /* Do not warn if this level of the initializer uses member
5437 designators; it is likely to be deliberate. */
5438 if (constructor_unfilled_fields && !constructor_designated)
5439 {
5440 push_member_name (constructor_unfilled_fields);
5441 warning_init ("missing initializer");
5442 RESTORE_SPELLING_DEPTH (constructor_depth);
5443 }
5444 }
5445
5446 /* Pad out the end of the structure. */
5447 if (p->replacement_value.value)
5448 /* If this closes a superfluous brace pair,
5449 just pass out the element between them. */
5450 ret = p->replacement_value;
5451 else if (constructor_type == 0)
5452 ;
5453 else if (TREE_CODE (constructor_type) != RECORD_TYPE
5454 && TREE_CODE (constructor_type) != UNION_TYPE
5455 && TREE_CODE (constructor_type) != ARRAY_TYPE
5456 && TREE_CODE (constructor_type) != VECTOR_TYPE)
5457 {
5458 /* A nonincremental scalar initializer--just return
5459 the element, after verifying there is just one. */
5460 if (VEC_empty (constructor_elt,constructor_elements))
5461 {
5462 if (!constructor_erroneous)
5463 error_init ("empty scalar initializer");
5464 ret.value = error_mark_node;
5465 }
5466 else if (VEC_length (constructor_elt,constructor_elements) != 1)
5467 {
5468 error_init ("extra elements in scalar initializer");
5469 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
5470 }
5471 else
5472 ret.value = VEC_index (constructor_elt,constructor_elements,0)->value;
5473 }
5474 else
5475 {
5476 if (constructor_erroneous)
5477 ret.value = error_mark_node;
5478 else
5479 {
5480 ret.value = build_constructor (constructor_type,
5481 constructor_elements);
5482 if (constructor_constant)
5483 TREE_CONSTANT (ret.value) = TREE_INVARIANT (ret.value) = 1;
5484 if (constructor_constant && constructor_simple)
5485 TREE_STATIC (ret.value) = 1;
5486 }
5487 }
5488
5489 constructor_type = p->type;
5490 constructor_fields = p->fields;
5491 constructor_index = p->index;
5492 constructor_max_index = p->max_index;
5493 constructor_unfilled_index = p->unfilled_index;
5494 constructor_unfilled_fields = p->unfilled_fields;
5495 constructor_bit_index = p->bit_index;
5496 constructor_elements = p->elements;
5497 constructor_constant = p->constant;
5498 constructor_simple = p->simple;
5499 constructor_erroneous = p->erroneous;
5500 constructor_incremental = p->incremental;
5501 constructor_designated = p->designated;
5502 constructor_pending_elts = p->pending_elts;
5503 constructor_depth = p->depth;
5504 if (!p->implicit)
5505 constructor_range_stack = p->range_stack;
5506 RESTORE_SPELLING_DEPTH (constructor_depth);
5507
5508 constructor_stack = p->next;
5509 free (p);
5510
5511 if (ret.value == 0 && constructor_stack == 0)
5512 ret.value = error_mark_node;
5513 return ret;
5514 }
5515
5516 /* Common handling for both array range and field name designators.
5517 ARRAY argument is nonzero for array ranges. Returns zero for success. */
5518
5519 static int
set_designator(int array)5520 set_designator (int array)
5521 {
5522 tree subtype;
5523 enum tree_code subcode;
5524
5525 /* Don't die if an entire brace-pair level is superfluous
5526 in the containing level. */
5527 if (constructor_type == 0)
5528 return 1;
5529
5530 /* If there were errors in this designator list already, bail out
5531 silently. */
5532 if (designator_erroneous)
5533 return 1;
5534
5535 if (!designator_depth)
5536 {
5537 gcc_assert (!constructor_range_stack);
5538
5539 /* Designator list starts at the level of closest explicit
5540 braces. */
5541 while (constructor_stack->implicit)
5542 process_init_element (pop_init_level (1));
5543 constructor_designated = 1;
5544 return 0;
5545 }
5546
5547 switch (TREE_CODE (constructor_type))
5548 {
5549 case RECORD_TYPE:
5550 case UNION_TYPE:
5551 subtype = TREE_TYPE (constructor_fields);
5552 if (subtype != error_mark_node)
5553 subtype = TYPE_MAIN_VARIANT (subtype);
5554 break;
5555 case ARRAY_TYPE:
5556 subtype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
5557 break;
5558 default:
5559 gcc_unreachable ();
5560 }
5561
5562 subcode = TREE_CODE (subtype);
5563 if (array && subcode != ARRAY_TYPE)
5564 {
5565 error_init ("array index in non-array initializer");
5566 return 1;
5567 }
5568 else if (!array && subcode != RECORD_TYPE && subcode != UNION_TYPE)
5569 {
5570 error_init ("field name not in record or union initializer");
5571 return 1;
5572 }
5573
5574 constructor_designated = 1;
5575 push_init_level (2);
5576 return 0;
5577 }
5578
5579 /* If there are range designators in designator list, push a new designator
5580 to constructor_range_stack. RANGE_END is end of such stack range or
5581 NULL_TREE if there is no range designator at this level. */
5582
5583 static void
push_range_stack(tree range_end)5584 push_range_stack (tree range_end)
5585 {
5586 struct constructor_range_stack *p;
5587
5588 p = GGC_NEW (struct constructor_range_stack);
5589 p->prev = constructor_range_stack;
5590 p->next = 0;
5591 p->fields = constructor_fields;
5592 p->range_start = constructor_index;
5593 p->index = constructor_index;
5594 p->stack = constructor_stack;
5595 p->range_end = range_end;
5596 if (constructor_range_stack)
5597 constructor_range_stack->next = p;
5598 constructor_range_stack = p;
5599 }
5600
5601 /* Within an array initializer, specify the next index to be initialized.
5602 FIRST is that index. If LAST is nonzero, then initialize a range
5603 of indices, running from FIRST through LAST. */
5604
5605 void
set_init_index(tree first,tree last)5606 set_init_index (tree first, tree last)
5607 {
5608 if (set_designator (1))
5609 return;
5610
5611 designator_erroneous = 1;
5612
5613 if (!INTEGRAL_TYPE_P (TREE_TYPE (first))
5614 || (last && !INTEGRAL_TYPE_P (TREE_TYPE (last))))
5615 {
5616 error_init ("array index in initializer not of integer type");
5617 return;
5618 }
5619
5620 if (TREE_CODE (first) != INTEGER_CST)
5621 error_init ("nonconstant array index in initializer");
5622 else if (last != 0 && TREE_CODE (last) != INTEGER_CST)
5623 error_init ("nonconstant array index in initializer");
5624 else if (TREE_CODE (constructor_type) != ARRAY_TYPE)
5625 error_init ("array index in non-array initializer");
5626 else if (tree_int_cst_sgn (first) == -1)
5627 error_init ("array index in initializer exceeds array bounds");
5628 else if (constructor_max_index
5629 && tree_int_cst_lt (constructor_max_index, first))
5630 error_init ("array index in initializer exceeds array bounds");
5631 else
5632 {
5633 constructor_index = convert (bitsizetype, first);
5634
5635 if (last)
5636 {
5637 if (tree_int_cst_equal (first, last))
5638 last = 0;
5639 else if (tree_int_cst_lt (last, first))
5640 {
5641 error_init ("empty index range in initializer");
5642 last = 0;
5643 }
5644 else
5645 {
5646 last = convert (bitsizetype, last);
5647 if (constructor_max_index != 0
5648 && tree_int_cst_lt (constructor_max_index, last))
5649 {
5650 error_init ("array index range in initializer exceeds array bounds");
5651 last = 0;
5652 }
5653 }
5654 }
5655
5656 designator_depth++;
5657 designator_erroneous = 0;
5658 if (constructor_range_stack || last)
5659 push_range_stack (last);
5660 }
5661 }
5662
5663 /* Within a struct initializer, specify the next field to be initialized. */
5664
5665 void
set_init_label(tree fieldname)5666 set_init_label (tree fieldname)
5667 {
5668 tree tail;
5669
5670 if (set_designator (0))
5671 return;
5672
5673 designator_erroneous = 1;
5674
5675 if (TREE_CODE (constructor_type) != RECORD_TYPE
5676 && TREE_CODE (constructor_type) != UNION_TYPE)
5677 {
5678 error_init ("field name not in record or union initializer");
5679 return;
5680 }
5681
5682 for (tail = TYPE_FIELDS (constructor_type); tail;
5683 tail = TREE_CHAIN (tail))
5684 {
5685 if (DECL_NAME (tail) == fieldname)
5686 break;
5687 }
5688
5689 if (tail == 0)
5690 error ("unknown field %qE specified in initializer", fieldname);
5691 else
5692 {
5693 constructor_fields = tail;
5694 designator_depth++;
5695 designator_erroneous = 0;
5696 if (constructor_range_stack)
5697 push_range_stack (NULL_TREE);
5698 }
5699 }
5700
5701 /* Add a new initializer to the tree of pending initializers. PURPOSE
5702 identifies the initializer, either array index or field in a structure.
5703 VALUE is the value of that index or field. */
5704
5705 static void
add_pending_init(tree purpose,tree value)5706 add_pending_init (tree purpose, tree value)
5707 {
5708 struct init_node *p, **q, *r;
5709
5710 q = &constructor_pending_elts;
5711 p = 0;
5712
5713 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5714 {
5715 while (*q != 0)
5716 {
5717 p = *q;
5718 if (tree_int_cst_lt (purpose, p->purpose))
5719 q = &p->left;
5720 else if (tree_int_cst_lt (p->purpose, purpose))
5721 q = &p->right;
5722 else
5723 {
5724 if (TREE_SIDE_EFFECTS (p->value))
5725 warning_init ("initialized field with side-effects overwritten");
5726 else if (warn_override_init)
5727 warning_init ("initialized field overwritten");
5728 p->value = value;
5729 return;
5730 }
5731 }
5732 }
5733 else
5734 {
5735 tree bitpos;
5736
5737 bitpos = bit_position (purpose);
5738 while (*q != NULL)
5739 {
5740 p = *q;
5741 if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
5742 q = &p->left;
5743 else if (p->purpose != purpose)
5744 q = &p->right;
5745 else
5746 {
5747 if (TREE_SIDE_EFFECTS (p->value))
5748 warning_init ("initialized field with side-effects overwritten");
5749 else if (warn_override_init)
5750 warning_init ("initialized field overwritten");
5751 p->value = value;
5752 return;
5753 }
5754 }
5755 }
5756
5757 r = GGC_NEW (struct init_node);
5758 r->purpose = purpose;
5759 r->value = value;
5760
5761 *q = r;
5762 r->parent = p;
5763 r->left = 0;
5764 r->right = 0;
5765 r->balance = 0;
5766
5767 while (p)
5768 {
5769 struct init_node *s;
5770
5771 if (r == p->left)
5772 {
5773 if (p->balance == 0)
5774 p->balance = -1;
5775 else if (p->balance < 0)
5776 {
5777 if (r->balance < 0)
5778 {
5779 /* L rotation. */
5780 p->left = r->right;
5781 if (p->left)
5782 p->left->parent = p;
5783 r->right = p;
5784
5785 p->balance = 0;
5786 r->balance = 0;
5787
5788 s = p->parent;
5789 p->parent = r;
5790 r->parent = s;
5791 if (s)
5792 {
5793 if (s->left == p)
5794 s->left = r;
5795 else
5796 s->right = r;
5797 }
5798 else
5799 constructor_pending_elts = r;
5800 }
5801 else
5802 {
5803 /* LR rotation. */
5804 struct init_node *t = r->right;
5805
5806 r->right = t->left;
5807 if (r->right)
5808 r->right->parent = r;
5809 t->left = r;
5810
5811 p->left = t->right;
5812 if (p->left)
5813 p->left->parent = p;
5814 t->right = p;
5815
5816 p->balance = t->balance < 0;
5817 r->balance = -(t->balance > 0);
5818 t->balance = 0;
5819
5820 s = p->parent;
5821 p->parent = t;
5822 r->parent = t;
5823 t->parent = s;
5824 if (s)
5825 {
5826 if (s->left == p)
5827 s->left = t;
5828 else
5829 s->right = t;
5830 }
5831 else
5832 constructor_pending_elts = t;
5833 }
5834 break;
5835 }
5836 else
5837 {
5838 /* p->balance == +1; growth of left side balances the node. */
5839 p->balance = 0;
5840 break;
5841 }
5842 }
5843 else /* r == p->right */
5844 {
5845 if (p->balance == 0)
5846 /* Growth propagation from right side. */
5847 p->balance++;
5848 else if (p->balance > 0)
5849 {
5850 if (r->balance > 0)
5851 {
5852 /* R rotation. */
5853 p->right = r->left;
5854 if (p->right)
5855 p->right->parent = p;
5856 r->left = p;
5857
5858 p->balance = 0;
5859 r->balance = 0;
5860
5861 s = p->parent;
5862 p->parent = r;
5863 r->parent = s;
5864 if (s)
5865 {
5866 if (s->left == p)
5867 s->left = r;
5868 else
5869 s->right = r;
5870 }
5871 else
5872 constructor_pending_elts = r;
5873 }
5874 else /* r->balance == -1 */
5875 {
5876 /* RL rotation */
5877 struct init_node *t = r->left;
5878
5879 r->left = t->right;
5880 if (r->left)
5881 r->left->parent = r;
5882 t->right = r;
5883
5884 p->right = t->left;
5885 if (p->right)
5886 p->right->parent = p;
5887 t->left = p;
5888
5889 r->balance = (t->balance < 0);
5890 p->balance = -(t->balance > 0);
5891 t->balance = 0;
5892
5893 s = p->parent;
5894 p->parent = t;
5895 r->parent = t;
5896 t->parent = s;
5897 if (s)
5898 {
5899 if (s->left == p)
5900 s->left = t;
5901 else
5902 s->right = t;
5903 }
5904 else
5905 constructor_pending_elts = t;
5906 }
5907 break;
5908 }
5909 else
5910 {
5911 /* p->balance == -1; growth of right side balances the node. */
5912 p->balance = 0;
5913 break;
5914 }
5915 }
5916
5917 r = p;
5918 p = p->parent;
5919 }
5920 }
5921
5922 /* Build AVL tree from a sorted chain. */
5923
5924 static void
set_nonincremental_init(void)5925 set_nonincremental_init (void)
5926 {
5927 unsigned HOST_WIDE_INT ix;
5928 tree index, value;
5929
5930 if (TREE_CODE (constructor_type) != RECORD_TYPE
5931 && TREE_CODE (constructor_type) != ARRAY_TYPE)
5932 return;
5933
5934 FOR_EACH_CONSTRUCTOR_ELT (constructor_elements, ix, index, value)
5935 add_pending_init (index, value);
5936 constructor_elements = 0;
5937 if (TREE_CODE (constructor_type) == RECORD_TYPE)
5938 {
5939 constructor_unfilled_fields = TYPE_FIELDS (constructor_type);
5940 /* Skip any nameless bit fields at the beginning. */
5941 while (constructor_unfilled_fields != 0
5942 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
5943 && DECL_NAME (constructor_unfilled_fields) == 0)
5944 constructor_unfilled_fields = TREE_CHAIN (constructor_unfilled_fields);
5945
5946 }
5947 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
5948 {
5949 if (TYPE_DOMAIN (constructor_type))
5950 constructor_unfilled_index
5951 = convert (bitsizetype,
5952 TYPE_MIN_VALUE (TYPE_DOMAIN (constructor_type)));
5953 else
5954 constructor_unfilled_index = bitsize_zero_node;
5955 }
5956 constructor_incremental = 0;
5957 }
5958
5959 /* Build AVL tree from a string constant. */
5960
5961 static void
set_nonincremental_init_from_string(tree str)5962 set_nonincremental_init_from_string (tree str)
5963 {
5964 tree value, purpose, type;
5965 HOST_WIDE_INT val[2];
5966 const char *p, *end;
5967 int byte, wchar_bytes, charwidth, bitpos;
5968
5969 gcc_assert (TREE_CODE (constructor_type) == ARRAY_TYPE);
5970
5971 if (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5972 == TYPE_PRECISION (char_type_node))
5973 wchar_bytes = 1;
5974 else
5975 {
5976 gcc_assert (TYPE_PRECISION (TREE_TYPE (TREE_TYPE (str)))
5977 == TYPE_PRECISION (wchar_type_node));
5978 wchar_bytes = TYPE_PRECISION (wchar_type_node) / BITS_PER_UNIT;
5979 }
5980 charwidth = TYPE_PRECISION (char_type_node);
5981 type = TREE_TYPE (constructor_type);
5982 p = TREE_STRING_POINTER (str);
5983 end = p + TREE_STRING_LENGTH (str);
5984
5985 for (purpose = bitsize_zero_node;
5986 p < end && !tree_int_cst_lt (constructor_max_index, purpose);
5987 purpose = size_binop (PLUS_EXPR, purpose, bitsize_one_node))
5988 {
5989 if (wchar_bytes == 1)
5990 {
5991 val[1] = (unsigned char) *p++;
5992 val[0] = 0;
5993 }
5994 else
5995 {
5996 val[0] = 0;
5997 val[1] = 0;
5998 for (byte = 0; byte < wchar_bytes; byte++)
5999 {
6000 if (BYTES_BIG_ENDIAN)
6001 bitpos = (wchar_bytes - byte - 1) * charwidth;
6002 else
6003 bitpos = byte * charwidth;
6004 val[bitpos < HOST_BITS_PER_WIDE_INT]
6005 |= ((unsigned HOST_WIDE_INT) ((unsigned char) *p++))
6006 << (bitpos % HOST_BITS_PER_WIDE_INT);
6007 }
6008 }
6009
6010 if (!TYPE_UNSIGNED (type))
6011 {
6012 bitpos = ((wchar_bytes - 1) * charwidth) + HOST_BITS_PER_CHAR;
6013 if (bitpos < HOST_BITS_PER_WIDE_INT)
6014 {
6015 if (val[1] & (((HOST_WIDE_INT) 1) << (bitpos - 1)))
6016 {
6017 val[1] |= ((HOST_WIDE_INT) -1) << bitpos;
6018 val[0] = -1;
6019 }
6020 }
6021 else if (bitpos == HOST_BITS_PER_WIDE_INT)
6022 {
6023 if (val[1] < 0)
6024 val[0] = -1;
6025 }
6026 else if (val[0] & (((HOST_WIDE_INT) 1)
6027 << (bitpos - 1 - HOST_BITS_PER_WIDE_INT)))
6028 val[0] |= ((HOST_WIDE_INT) -1)
6029 << (bitpos - HOST_BITS_PER_WIDE_INT);
6030 }
6031
6032 value = build_int_cst_wide (type, val[1], val[0]);
6033 add_pending_init (purpose, value);
6034 }
6035
6036 constructor_incremental = 0;
6037 }
6038
6039 /* Return value of FIELD in pending initializer or zero if the field was
6040 not initialized yet. */
6041
6042 static tree
find_init_member(tree field)6043 find_init_member (tree field)
6044 {
6045 struct init_node *p;
6046
6047 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6048 {
6049 if (constructor_incremental
6050 && tree_int_cst_lt (field, constructor_unfilled_index))
6051 set_nonincremental_init ();
6052
6053 p = constructor_pending_elts;
6054 while (p)
6055 {
6056 if (tree_int_cst_lt (field, p->purpose))
6057 p = p->left;
6058 else if (tree_int_cst_lt (p->purpose, field))
6059 p = p->right;
6060 else
6061 return p->value;
6062 }
6063 }
6064 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6065 {
6066 tree bitpos = bit_position (field);
6067
6068 if (constructor_incremental
6069 && (!constructor_unfilled_fields
6070 || tree_int_cst_lt (bitpos,
6071 bit_position (constructor_unfilled_fields))))
6072 set_nonincremental_init ();
6073
6074 p = constructor_pending_elts;
6075 while (p)
6076 {
6077 if (field == p->purpose)
6078 return p->value;
6079 else if (tree_int_cst_lt (bitpos, bit_position (p->purpose)))
6080 p = p->left;
6081 else
6082 p = p->right;
6083 }
6084 }
6085 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6086 {
6087 if (!VEC_empty (constructor_elt, constructor_elements)
6088 && (VEC_last (constructor_elt, constructor_elements)->index
6089 == field))
6090 return VEC_last (constructor_elt, constructor_elements)->value;
6091 }
6092 return 0;
6093 }
6094
6095 /* "Output" the next constructor element.
6096 At top level, really output it to assembler code now.
6097 Otherwise, collect it in a list from which we will make a CONSTRUCTOR.
6098 TYPE is the data type that the containing data type wants here.
6099 FIELD is the field (a FIELD_DECL) or the index that this element fills.
6100 If VALUE is a string constant, STRICT_STRING is true if it is
6101 unparenthesized or we should not warn here for it being parenthesized.
6102 For other types of VALUE, STRICT_STRING is not used.
6103
6104 PENDING if non-nil means output pending elements that belong
6105 right after this element. (PENDING is normally 1;
6106 it is 0 while outputting pending elements, to avoid recursion.) */
6107
6108 static void
output_init_element(tree value,bool strict_string,tree type,tree field,int pending)6109 output_init_element (tree value, bool strict_string, tree type, tree field,
6110 int pending)
6111 {
6112 constructor_elt *celt;
6113
6114 if (type == error_mark_node || value == error_mark_node)
6115 {
6116 constructor_erroneous = 1;
6117 return;
6118 }
6119 if (TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
6120 && (TREE_CODE (value) == STRING_CST
6121 || TREE_CODE (value) == COMPOUND_LITERAL_EXPR)
6122 && !(TREE_CODE (value) == STRING_CST
6123 && TREE_CODE (type) == ARRAY_TYPE
6124 && INTEGRAL_TYPE_P (TREE_TYPE (type)))
6125 && !comptypes (TYPE_MAIN_VARIANT (TREE_TYPE (value)),
6126 TYPE_MAIN_VARIANT (type)))
6127 value = array_to_pointer_conversion (value);
6128
6129 if (TREE_CODE (value) == COMPOUND_LITERAL_EXPR
6130 && require_constant_value && !flag_isoc99 && pending)
6131 {
6132 /* As an extension, allow initializing objects with static storage
6133 duration with compound literals (which are then treated just as
6134 the brace enclosed list they contain). */
6135 tree decl = COMPOUND_LITERAL_EXPR_DECL (value);
6136 value = DECL_INITIAL (decl);
6137 }
6138
6139 if (value == error_mark_node)
6140 constructor_erroneous = 1;
6141 else if (!TREE_CONSTANT (value))
6142 constructor_constant = 0;
6143 else if (!initializer_constant_valid_p (value, TREE_TYPE (value))
6144 || ((TREE_CODE (constructor_type) == RECORD_TYPE
6145 || TREE_CODE (constructor_type) == UNION_TYPE)
6146 && DECL_C_BIT_FIELD (field)
6147 && TREE_CODE (value) != INTEGER_CST))
6148 constructor_simple = 0;
6149
6150 if (!initializer_constant_valid_p (value, TREE_TYPE (value)))
6151 {
6152 if (require_constant_value)
6153 {
6154 error_init ("initializer element is not constant");
6155 value = error_mark_node;
6156 }
6157 else if (require_constant_elements)
6158 pedwarn ("initializer element is not computable at load time");
6159 }
6160
6161 /* If this field is empty (and not at the end of structure),
6162 don't do anything other than checking the initializer. */
6163 if (field
6164 && (TREE_TYPE (field) == error_mark_node
6165 || (COMPLETE_TYPE_P (TREE_TYPE (field))
6166 && integer_zerop (TYPE_SIZE (TREE_TYPE (field)))
6167 && (TREE_CODE (constructor_type) == ARRAY_TYPE
6168 || TREE_CHAIN (field)))))
6169 return;
6170
6171 value = digest_init (type, value, strict_string, require_constant_value);
6172 if (value == error_mark_node)
6173 {
6174 constructor_erroneous = 1;
6175 return;
6176 }
6177
6178 /* If this element doesn't come next in sequence,
6179 put it on constructor_pending_elts. */
6180 if (TREE_CODE (constructor_type) == ARRAY_TYPE
6181 && (!constructor_incremental
6182 || !tree_int_cst_equal (field, constructor_unfilled_index)))
6183 {
6184 if (constructor_incremental
6185 && tree_int_cst_lt (field, constructor_unfilled_index))
6186 set_nonincremental_init ();
6187
6188 add_pending_init (field, value);
6189 return;
6190 }
6191 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6192 && (!constructor_incremental
6193 || field != constructor_unfilled_fields))
6194 {
6195 /* We do this for records but not for unions. In a union,
6196 no matter which field is specified, it can be initialized
6197 right away since it starts at the beginning of the union. */
6198 if (constructor_incremental)
6199 {
6200 if (!constructor_unfilled_fields)
6201 set_nonincremental_init ();
6202 else
6203 {
6204 tree bitpos, unfillpos;
6205
6206 bitpos = bit_position (field);
6207 unfillpos = bit_position (constructor_unfilled_fields);
6208
6209 if (tree_int_cst_lt (bitpos, unfillpos))
6210 set_nonincremental_init ();
6211 }
6212 }
6213
6214 add_pending_init (field, value);
6215 return;
6216 }
6217 else if (TREE_CODE (constructor_type) == UNION_TYPE
6218 && !VEC_empty (constructor_elt, constructor_elements))
6219 {
6220 if (TREE_SIDE_EFFECTS (VEC_last (constructor_elt,
6221 constructor_elements)->value))
6222 warning_init ("initialized field with side-effects overwritten");
6223 else if (warn_override_init)
6224 warning_init ("initialized field overwritten");
6225
6226 /* We can have just one union field set. */
6227 constructor_elements = 0;
6228 }
6229
6230 /* Otherwise, output this element either to
6231 constructor_elements or to the assembler file. */
6232
6233 celt = VEC_safe_push (constructor_elt, gc, constructor_elements, NULL);
6234 celt->index = field;
6235 celt->value = value;
6236
6237 /* Advance the variable that indicates sequential elements output. */
6238 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6239 constructor_unfilled_index
6240 = size_binop (PLUS_EXPR, constructor_unfilled_index,
6241 bitsize_one_node);
6242 else if (TREE_CODE (constructor_type) == RECORD_TYPE)
6243 {
6244 constructor_unfilled_fields
6245 = TREE_CHAIN (constructor_unfilled_fields);
6246
6247 /* Skip any nameless bit fields. */
6248 while (constructor_unfilled_fields != 0
6249 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6250 && DECL_NAME (constructor_unfilled_fields) == 0)
6251 constructor_unfilled_fields =
6252 TREE_CHAIN (constructor_unfilled_fields);
6253 }
6254 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6255 constructor_unfilled_fields = 0;
6256
6257 /* Now output any pending elements which have become next. */
6258 if (pending)
6259 output_pending_init_elements (0);
6260 }
6261
6262 /* Output any pending elements which have become next.
6263 As we output elements, constructor_unfilled_{fields,index}
6264 advances, which may cause other elements to become next;
6265 if so, they too are output.
6266
6267 If ALL is 0, we return when there are
6268 no more pending elements to output now.
6269
6270 If ALL is 1, we output space as necessary so that
6271 we can output all the pending elements. */
6272
6273 static void
output_pending_init_elements(int all)6274 output_pending_init_elements (int all)
6275 {
6276 struct init_node *elt = constructor_pending_elts;
6277 tree next;
6278
6279 retry:
6280
6281 /* Look through the whole pending tree.
6282 If we find an element that should be output now,
6283 output it. Otherwise, set NEXT to the element
6284 that comes first among those still pending. */
6285
6286 next = 0;
6287 while (elt)
6288 {
6289 if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6290 {
6291 if (tree_int_cst_equal (elt->purpose,
6292 constructor_unfilled_index))
6293 output_init_element (elt->value, true,
6294 TREE_TYPE (constructor_type),
6295 constructor_unfilled_index, 0);
6296 else if (tree_int_cst_lt (constructor_unfilled_index,
6297 elt->purpose))
6298 {
6299 /* Advance to the next smaller node. */
6300 if (elt->left)
6301 elt = elt->left;
6302 else
6303 {
6304 /* We have reached the smallest node bigger than the
6305 current unfilled index. Fill the space first. */
6306 next = elt->purpose;
6307 break;
6308 }
6309 }
6310 else
6311 {
6312 /* Advance to the next bigger node. */
6313 if (elt->right)
6314 elt = elt->right;
6315 else
6316 {
6317 /* We have reached the biggest node in a subtree. Find
6318 the parent of it, which is the next bigger node. */
6319 while (elt->parent && elt->parent->right == elt)
6320 elt = elt->parent;
6321 elt = elt->parent;
6322 if (elt && tree_int_cst_lt (constructor_unfilled_index,
6323 elt->purpose))
6324 {
6325 next = elt->purpose;
6326 break;
6327 }
6328 }
6329 }
6330 }
6331 else if (TREE_CODE (constructor_type) == RECORD_TYPE
6332 || TREE_CODE (constructor_type) == UNION_TYPE)
6333 {
6334 tree ctor_unfilled_bitpos, elt_bitpos;
6335
6336 /* If the current record is complete we are done. */
6337 if (constructor_unfilled_fields == 0)
6338 break;
6339
6340 ctor_unfilled_bitpos = bit_position (constructor_unfilled_fields);
6341 elt_bitpos = bit_position (elt->purpose);
6342 /* We can't compare fields here because there might be empty
6343 fields in between. */
6344 if (tree_int_cst_equal (elt_bitpos, ctor_unfilled_bitpos))
6345 {
6346 constructor_unfilled_fields = elt->purpose;
6347 output_init_element (elt->value, true, TREE_TYPE (elt->purpose),
6348 elt->purpose, 0);
6349 }
6350 else if (tree_int_cst_lt (ctor_unfilled_bitpos, elt_bitpos))
6351 {
6352 /* Advance to the next smaller node. */
6353 if (elt->left)
6354 elt = elt->left;
6355 else
6356 {
6357 /* We have reached the smallest node bigger than the
6358 current unfilled field. Fill the space first. */
6359 next = elt->purpose;
6360 break;
6361 }
6362 }
6363 else
6364 {
6365 /* Advance to the next bigger node. */
6366 if (elt->right)
6367 elt = elt->right;
6368 else
6369 {
6370 /* We have reached the biggest node in a subtree. Find
6371 the parent of it, which is the next bigger node. */
6372 while (elt->parent && elt->parent->right == elt)
6373 elt = elt->parent;
6374 elt = elt->parent;
6375 if (elt
6376 && (tree_int_cst_lt (ctor_unfilled_bitpos,
6377 bit_position (elt->purpose))))
6378 {
6379 next = elt->purpose;
6380 break;
6381 }
6382 }
6383 }
6384 }
6385 }
6386
6387 /* Ordinarily return, but not if we want to output all
6388 and there are elements left. */
6389 if (!(all && next != 0))
6390 return;
6391
6392 /* If it's not incremental, just skip over the gap, so that after
6393 jumping to retry we will output the next successive element. */
6394 if (TREE_CODE (constructor_type) == RECORD_TYPE
6395 || TREE_CODE (constructor_type) == UNION_TYPE)
6396 constructor_unfilled_fields = next;
6397 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6398 constructor_unfilled_index = next;
6399
6400 /* ELT now points to the node in the pending tree with the next
6401 initializer to output. */
6402 goto retry;
6403 }
6404
6405 /* Add one non-braced element to the current constructor level.
6406 This adjusts the current position within the constructor's type.
6407 This may also start or terminate implicit levels
6408 to handle a partly-braced initializer.
6409
6410 Once this has found the correct level for the new element,
6411 it calls output_init_element. */
6412
6413 void
process_init_element(struct c_expr value)6414 process_init_element (struct c_expr value)
6415 {
6416 tree orig_value = value.value;
6417 int string_flag = orig_value != 0 && TREE_CODE (orig_value) == STRING_CST;
6418 bool strict_string = value.original_code == STRING_CST;
6419
6420 designator_depth = 0;
6421 designator_erroneous = 0;
6422
6423 /* Handle superfluous braces around string cst as in
6424 char x[] = {"foo"}; */
6425 if (string_flag
6426 && constructor_type
6427 && TREE_CODE (constructor_type) == ARRAY_TYPE
6428 && INTEGRAL_TYPE_P (TREE_TYPE (constructor_type))
6429 && integer_zerop (constructor_unfilled_index))
6430 {
6431 if (constructor_stack->replacement_value.value)
6432 error_init ("excess elements in char array initializer");
6433 constructor_stack->replacement_value = value;
6434 return;
6435 }
6436
6437 if (constructor_stack->replacement_value.value != 0)
6438 {
6439 error_init ("excess elements in struct initializer");
6440 return;
6441 }
6442
6443 /* Ignore elements of a brace group if it is entirely superfluous
6444 and has already been diagnosed. */
6445 if (constructor_type == 0)
6446 return;
6447
6448 /* If we've exhausted any levels that didn't have braces,
6449 pop them now. */
6450 while (constructor_stack->implicit)
6451 {
6452 if ((TREE_CODE (constructor_type) == RECORD_TYPE
6453 || TREE_CODE (constructor_type) == UNION_TYPE)
6454 && constructor_fields == 0)
6455 process_init_element (pop_init_level (1));
6456 else if (TREE_CODE (constructor_type) == ARRAY_TYPE
6457 && (constructor_max_index == 0
6458 || tree_int_cst_lt (constructor_max_index,
6459 constructor_index)))
6460 process_init_element (pop_init_level (1));
6461 else
6462 break;
6463 }
6464
6465 /* In the case of [LO ... HI] = VALUE, only evaluate VALUE once. */
6466 if (constructor_range_stack)
6467 {
6468 /* If value is a compound literal and we'll be just using its
6469 content, don't put it into a SAVE_EXPR. */
6470 if (TREE_CODE (value.value) != COMPOUND_LITERAL_EXPR
6471 || !require_constant_value
6472 || flag_isoc99)
6473 value.value = save_expr (value.value);
6474 }
6475
6476 while (1)
6477 {
6478 if (TREE_CODE (constructor_type) == RECORD_TYPE)
6479 {
6480 tree fieldtype;
6481 enum tree_code fieldcode;
6482
6483 if (constructor_fields == 0)
6484 {
6485 pedwarn_init ("excess elements in struct initializer");
6486 break;
6487 }
6488
6489 fieldtype = TREE_TYPE (constructor_fields);
6490 if (fieldtype != error_mark_node)
6491 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6492 fieldcode = TREE_CODE (fieldtype);
6493
6494 /* Error for non-static initialization of a flexible array member. */
6495 if (fieldcode == ARRAY_TYPE
6496 && !require_constant_value
6497 && TYPE_SIZE (fieldtype) == NULL_TREE
6498 && TREE_CHAIN (constructor_fields) == NULL_TREE)
6499 {
6500 error_init ("non-static initialization of a flexible array member");
6501 break;
6502 }
6503
6504 /* Accept a string constant to initialize a subarray. */
6505 if (value.value != 0
6506 && fieldcode == ARRAY_TYPE
6507 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6508 && string_flag)
6509 value.value = orig_value;
6510 /* Otherwise, if we have come to a subaggregate,
6511 and we don't have an element of its type, push into it. */
6512 else if (value.value != 0
6513 && value.value != error_mark_node
6514 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6515 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6516 || fieldcode == UNION_TYPE))
6517 {
6518 push_init_level (1);
6519 continue;
6520 }
6521
6522 if (value.value)
6523 {
6524 push_member_name (constructor_fields);
6525 output_init_element (value.value, strict_string,
6526 fieldtype, constructor_fields, 1);
6527 RESTORE_SPELLING_DEPTH (constructor_depth);
6528 }
6529 else
6530 /* Do the bookkeeping for an element that was
6531 directly output as a constructor. */
6532 {
6533 /* For a record, keep track of end position of last field. */
6534 if (DECL_SIZE (constructor_fields))
6535 constructor_bit_index
6536 = size_binop (PLUS_EXPR,
6537 bit_position (constructor_fields),
6538 DECL_SIZE (constructor_fields));
6539
6540 /* If the current field was the first one not yet written out,
6541 it isn't now, so update. */
6542 if (constructor_unfilled_fields == constructor_fields)
6543 {
6544 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6545 /* Skip any nameless bit fields. */
6546 while (constructor_unfilled_fields != 0
6547 && DECL_C_BIT_FIELD (constructor_unfilled_fields)
6548 && DECL_NAME (constructor_unfilled_fields) == 0)
6549 constructor_unfilled_fields =
6550 TREE_CHAIN (constructor_unfilled_fields);
6551 }
6552 }
6553
6554 constructor_fields = TREE_CHAIN (constructor_fields);
6555 /* Skip any nameless bit fields at the beginning. */
6556 while (constructor_fields != 0
6557 && DECL_C_BIT_FIELD (constructor_fields)
6558 && DECL_NAME (constructor_fields) == 0)
6559 constructor_fields = TREE_CHAIN (constructor_fields);
6560 }
6561 else if (TREE_CODE (constructor_type) == UNION_TYPE)
6562 {
6563 tree fieldtype;
6564 enum tree_code fieldcode;
6565
6566 if (constructor_fields == 0)
6567 {
6568 pedwarn_init ("excess elements in union initializer");
6569 break;
6570 }
6571
6572 fieldtype = TREE_TYPE (constructor_fields);
6573 if (fieldtype != error_mark_node)
6574 fieldtype = TYPE_MAIN_VARIANT (fieldtype);
6575 fieldcode = TREE_CODE (fieldtype);
6576
6577 /* Warn that traditional C rejects initialization of unions.
6578 We skip the warning if the value is zero. This is done
6579 under the assumption that the zero initializer in user
6580 code appears conditioned on e.g. __STDC__ to avoid
6581 "missing initializer" warnings and relies on default
6582 initialization to zero in the traditional C case.
6583 We also skip the warning if the initializer is designated,
6584 again on the assumption that this must be conditional on
6585 __STDC__ anyway (and we've already complained about the
6586 member-designator already). */
6587 if (!in_system_header && !constructor_designated
6588 && !(value.value && (integer_zerop (value.value)
6589 || real_zerop (value.value))))
6590 warning (OPT_Wtraditional, "traditional C rejects initialization "
6591 "of unions");
6592
6593 /* Accept a string constant to initialize a subarray. */
6594 if (value.value != 0
6595 && fieldcode == ARRAY_TYPE
6596 && INTEGRAL_TYPE_P (TREE_TYPE (fieldtype))
6597 && string_flag)
6598 value.value = orig_value;
6599 /* Otherwise, if we have come to a subaggregate,
6600 and we don't have an element of its type, push into it. */
6601 else if (value.value != 0
6602 && value.value != error_mark_node
6603 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != fieldtype
6604 && (fieldcode == RECORD_TYPE || fieldcode == ARRAY_TYPE
6605 || fieldcode == UNION_TYPE))
6606 {
6607 push_init_level (1);
6608 continue;
6609 }
6610
6611 if (value.value)
6612 {
6613 push_member_name (constructor_fields);
6614 output_init_element (value.value, strict_string,
6615 fieldtype, constructor_fields, 1);
6616 RESTORE_SPELLING_DEPTH (constructor_depth);
6617 }
6618 else
6619 /* Do the bookkeeping for an element that was
6620 directly output as a constructor. */
6621 {
6622 constructor_bit_index = DECL_SIZE (constructor_fields);
6623 constructor_unfilled_fields = TREE_CHAIN (constructor_fields);
6624 }
6625
6626 constructor_fields = 0;
6627 }
6628 else if (TREE_CODE (constructor_type) == ARRAY_TYPE)
6629 {
6630 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6631 enum tree_code eltcode = TREE_CODE (elttype);
6632
6633 /* Accept a string constant to initialize a subarray. */
6634 if (value.value != 0
6635 && eltcode == ARRAY_TYPE
6636 && INTEGRAL_TYPE_P (TREE_TYPE (elttype))
6637 && string_flag)
6638 value.value = orig_value;
6639 /* Otherwise, if we have come to a subaggregate,
6640 and we don't have an element of its type, push into it. */
6641 else if (value.value != 0
6642 && value.value != error_mark_node
6643 && TYPE_MAIN_VARIANT (TREE_TYPE (value.value)) != elttype
6644 && (eltcode == RECORD_TYPE || eltcode == ARRAY_TYPE
6645 || eltcode == UNION_TYPE))
6646 {
6647 push_init_level (1);
6648 continue;
6649 }
6650
6651 if (constructor_max_index != 0
6652 && (tree_int_cst_lt (constructor_max_index, constructor_index)
6653 || integer_all_onesp (constructor_max_index)))
6654 {
6655 pedwarn_init ("excess elements in array initializer");
6656 break;
6657 }
6658
6659 /* Now output the actual element. */
6660 if (value.value)
6661 {
6662 push_array_bounds (tree_low_cst (constructor_index, 1));
6663 output_init_element (value.value, strict_string,
6664 elttype, constructor_index, 1);
6665 RESTORE_SPELLING_DEPTH (constructor_depth);
6666 }
6667
6668 constructor_index
6669 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6670
6671 if (!value.value)
6672 /* If we are doing the bookkeeping for an element that was
6673 directly output as a constructor, we must update
6674 constructor_unfilled_index. */
6675 constructor_unfilled_index = constructor_index;
6676 }
6677 else if (TREE_CODE (constructor_type) == VECTOR_TYPE)
6678 {
6679 tree elttype = TYPE_MAIN_VARIANT (TREE_TYPE (constructor_type));
6680
6681 /* Do a basic check of initializer size. Note that vectors
6682 always have a fixed size derived from their type. */
6683 if (tree_int_cst_lt (constructor_max_index, constructor_index))
6684 {
6685 pedwarn_init ("excess elements in vector initializer");
6686 break;
6687 }
6688
6689 /* Now output the actual element. */
6690 if (value.value)
6691 output_init_element (value.value, strict_string,
6692 elttype, constructor_index, 1);
6693
6694 constructor_index
6695 = size_binop (PLUS_EXPR, constructor_index, bitsize_one_node);
6696
6697 if (!value.value)
6698 /* If we are doing the bookkeeping for an element that was
6699 directly output as a constructor, we must update
6700 constructor_unfilled_index. */
6701 constructor_unfilled_index = constructor_index;
6702 }
6703
6704 /* Handle the sole element allowed in a braced initializer
6705 for a scalar variable. */
6706 else if (constructor_type != error_mark_node
6707 && constructor_fields == 0)
6708 {
6709 pedwarn_init ("excess elements in scalar initializer");
6710 break;
6711 }
6712 else
6713 {
6714 if (value.value)
6715 output_init_element (value.value, strict_string,
6716 constructor_type, NULL_TREE, 1);
6717 constructor_fields = 0;
6718 }
6719
6720 /* Handle range initializers either at this level or anywhere higher
6721 in the designator stack. */
6722 if (constructor_range_stack)
6723 {
6724 struct constructor_range_stack *p, *range_stack;
6725 int finish = 0;
6726
6727 range_stack = constructor_range_stack;
6728 constructor_range_stack = 0;
6729 while (constructor_stack != range_stack->stack)
6730 {
6731 gcc_assert (constructor_stack->implicit);
6732 process_init_element (pop_init_level (1));
6733 }
6734 for (p = range_stack;
6735 !p->range_end || tree_int_cst_equal (p->index, p->range_end);
6736 p = p->prev)
6737 {
6738 gcc_assert (constructor_stack->implicit);
6739 process_init_element (pop_init_level (1));
6740 }
6741
6742 p->index = size_binop (PLUS_EXPR, p->index, bitsize_one_node);
6743 if (tree_int_cst_equal (p->index, p->range_end) && !p->prev)
6744 finish = 1;
6745
6746 while (1)
6747 {
6748 constructor_index = p->index;
6749 constructor_fields = p->fields;
6750 if (finish && p->range_end && p->index == p->range_start)
6751 {
6752 finish = 0;
6753 p->prev = 0;
6754 }
6755 p = p->next;
6756 if (!p)
6757 break;
6758 push_init_level (2);
6759 p->stack = constructor_stack;
6760 if (p->range_end && tree_int_cst_equal (p->index, p->range_end))
6761 p->index = p->range_start;
6762 }
6763
6764 if (!finish)
6765 constructor_range_stack = range_stack;
6766 continue;
6767 }
6768
6769 break;
6770 }
6771
6772 constructor_range_stack = 0;
6773 }
6774
6775 /* Build a complete asm-statement, whose components are a CV_QUALIFIER
6776 (guaranteed to be 'volatile' or null) and ARGS (represented using
6777 an ASM_EXPR node). */
6778 tree
build_asm_stmt(tree cv_qualifier,tree args)6779 build_asm_stmt (tree cv_qualifier, tree args)
6780 {
6781 if (!ASM_VOLATILE_P (args) && cv_qualifier)
6782 ASM_VOLATILE_P (args) = 1;
6783 return add_stmt (args);
6784 }
6785
6786 /* Build an asm-expr, whose components are a STRING, some OUTPUTS,
6787 some INPUTS, and some CLOBBERS. The latter three may be NULL.
6788 SIMPLE indicates whether there was anything at all after the
6789 string in the asm expression -- asm("blah") and asm("blah" : )
6790 are subtly different. We use a ASM_EXPR node to represent this. */
6791 tree
build_asm_expr(tree string,tree outputs,tree inputs,tree clobbers,bool simple)6792 build_asm_expr (tree string, tree outputs, tree inputs, tree clobbers,
6793 bool simple)
6794 {
6795 tree tail;
6796 tree args;
6797 int i;
6798 const char *constraint;
6799 const char **oconstraints;
6800 bool allows_mem, allows_reg, is_inout;
6801 int ninputs, noutputs;
6802
6803 ninputs = list_length (inputs);
6804 noutputs = list_length (outputs);
6805 oconstraints = (const char **) alloca (noutputs * sizeof (const char *));
6806
6807 string = resolve_asm_operand_names (string, outputs, inputs);
6808
6809 /* Remove output conversions that change the type but not the mode. */
6810 for (i = 0, tail = outputs; tail; ++i, tail = TREE_CHAIN (tail))
6811 {
6812 tree output = TREE_VALUE (tail);
6813
6814 /* ??? Really, this should not be here. Users should be using a
6815 proper lvalue, dammit. But there's a long history of using casts
6816 in the output operands. In cases like longlong.h, this becomes a
6817 primitive form of typechecking -- if the cast can be removed, then
6818 the output operand had a type of the proper width; otherwise we'll
6819 get an error. Gross, but ... */
6820 STRIP_NOPS (output);
6821
6822 if (!lvalue_or_else (output, lv_asm))
6823 output = error_mark_node;
6824
6825 if (output != error_mark_node
6826 && (TREE_READONLY (output)
6827 || TYPE_READONLY (TREE_TYPE (output))
6828 || ((TREE_CODE (TREE_TYPE (output)) == RECORD_TYPE
6829 || TREE_CODE (TREE_TYPE (output)) == UNION_TYPE)
6830 && C_TYPE_FIELDS_READONLY (TREE_TYPE (output)))))
6831 readonly_error (output, lv_asm);
6832
6833 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6834 oconstraints[i] = constraint;
6835
6836 if (parse_output_constraint (&constraint, i, ninputs, noutputs,
6837 &allows_mem, &allows_reg, &is_inout))
6838 {
6839 /* If the operand is going to end up in memory,
6840 mark it addressable. */
6841 if (!allows_reg && !c_mark_addressable (output))
6842 output = error_mark_node;
6843 }
6844 else
6845 output = error_mark_node;
6846
6847 TREE_VALUE (tail) = output;
6848 }
6849
6850 for (i = 0, tail = inputs; tail; ++i, tail = TREE_CHAIN (tail))
6851 {
6852 tree input;
6853
6854 constraint = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (tail)));
6855 input = TREE_VALUE (tail);
6856
6857 if (parse_input_constraint (&constraint, i, ninputs, noutputs, 0,
6858 oconstraints, &allows_mem, &allows_reg))
6859 {
6860 /* If the operand is going to end up in memory,
6861 mark it addressable. */
6862 if (!allows_reg && allows_mem)
6863 {
6864 /* Strip the nops as we allow this case. FIXME, this really
6865 should be rejected or made deprecated. */
6866 STRIP_NOPS (input);
6867 if (!c_mark_addressable (input))
6868 input = error_mark_node;
6869 }
6870 }
6871 else
6872 input = error_mark_node;
6873
6874 TREE_VALUE (tail) = input;
6875 }
6876
6877 args = build_stmt (ASM_EXPR, string, outputs, inputs, clobbers);
6878
6879 /* asm statements without outputs, including simple ones, are treated
6880 as volatile. */
6881 ASM_INPUT_P (args) = simple;
6882 ASM_VOLATILE_P (args) = (noutputs == 0);
6883
6884 return args;
6885 }
6886
6887 /* Generate a goto statement to LABEL. */
6888
6889 tree
c_finish_goto_label(tree label)6890 c_finish_goto_label (tree label)
6891 {
6892 tree decl = lookup_label (label);
6893 if (!decl)
6894 return NULL_TREE;
6895
6896 if (C_DECL_UNJUMPABLE_STMT_EXPR (decl))
6897 {
6898 error ("jump into statement expression");
6899 return NULL_TREE;
6900 }
6901
6902 if (C_DECL_UNJUMPABLE_VM (decl))
6903 {
6904 error ("jump into scope of identifier with variably modified type");
6905 return NULL_TREE;
6906 }
6907
6908 if (!C_DECL_UNDEFINABLE_STMT_EXPR (decl))
6909 {
6910 /* No jump from outside this statement expression context, so
6911 record that there is a jump from within this context. */
6912 struct c_label_list *nlist;
6913 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6914 nlist->next = label_context_stack_se->labels_used;
6915 nlist->label = decl;
6916 label_context_stack_se->labels_used = nlist;
6917 }
6918
6919 if (!C_DECL_UNDEFINABLE_VM (decl))
6920 {
6921 /* No jump from outside this context context of identifiers with
6922 variably modified type, so record that there is a jump from
6923 within this context. */
6924 struct c_label_list *nlist;
6925 nlist = XOBNEW (&parser_obstack, struct c_label_list);
6926 nlist->next = label_context_stack_vm->labels_used;
6927 nlist->label = decl;
6928 label_context_stack_vm->labels_used = nlist;
6929 }
6930
6931 TREE_USED (decl) = 1;
6932 return add_stmt (build1 (GOTO_EXPR, void_type_node, decl));
6933 }
6934
6935 /* Generate a computed goto statement to EXPR. */
6936
6937 tree
c_finish_goto_ptr(tree expr)6938 c_finish_goto_ptr (tree expr)
6939 {
6940 if (pedantic)
6941 pedwarn ("ISO C forbids %<goto *expr;%>");
6942 expr = convert (ptr_type_node, expr);
6943 return add_stmt (build1 (GOTO_EXPR, void_type_node, expr));
6944 }
6945
6946 /* Generate a C `return' statement. RETVAL is the expression for what
6947 to return, or a null pointer for `return;' with no value. */
6948
6949 tree
c_finish_return(tree retval)6950 c_finish_return (tree retval)
6951 {
6952 tree valtype = TREE_TYPE (TREE_TYPE (current_function_decl)), ret_stmt;
6953 bool no_warning = false;
6954
6955 if (TREE_THIS_VOLATILE (current_function_decl))
6956 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6957
6958 if (!retval)
6959 {
6960 current_function_returns_null = 1;
6961 if ((warn_return_type || flag_isoc99)
6962 && valtype != 0 && TREE_CODE (valtype) != VOID_TYPE)
6963 {
6964 pedwarn_c99 ("%<return%> with no value, in "
6965 "function returning non-void");
6966 no_warning = true;
6967 }
6968 }
6969 else if (valtype == 0 || TREE_CODE (valtype) == VOID_TYPE)
6970 {
6971 current_function_returns_null = 1;
6972 if (pedantic || TREE_CODE (TREE_TYPE (retval)) != VOID_TYPE)
6973 pedwarn ("%<return%> with a value, in function returning void");
6974 }
6975 else
6976 {
6977 tree t = convert_for_assignment (valtype, retval, ic_return,
6978 NULL_TREE, NULL_TREE, 0);
6979 tree res = DECL_RESULT (current_function_decl);
6980 tree inner;
6981
6982 current_function_returns_value = 1;
6983 if (t == error_mark_node)
6984 return NULL_TREE;
6985
6986 inner = t = convert (TREE_TYPE (res), t);
6987
6988 /* Strip any conversions, additions, and subtractions, and see if
6989 we are returning the address of a local variable. Warn if so. */
6990 while (1)
6991 {
6992 switch (TREE_CODE (inner))
6993 {
6994 case NOP_EXPR: case NON_LVALUE_EXPR: case CONVERT_EXPR:
6995 case PLUS_EXPR:
6996 inner = TREE_OPERAND (inner, 0);
6997 continue;
6998
6999 case MINUS_EXPR:
7000 /* If the second operand of the MINUS_EXPR has a pointer
7001 type (or is converted from it), this may be valid, so
7002 don't give a warning. */
7003 {
7004 tree op1 = TREE_OPERAND (inner, 1);
7005
7006 while (!POINTER_TYPE_P (TREE_TYPE (op1))
7007 && (TREE_CODE (op1) == NOP_EXPR
7008 || TREE_CODE (op1) == NON_LVALUE_EXPR
7009 || TREE_CODE (op1) == CONVERT_EXPR))
7010 op1 = TREE_OPERAND (op1, 0);
7011
7012 if (POINTER_TYPE_P (TREE_TYPE (op1)))
7013 break;
7014
7015 inner = TREE_OPERAND (inner, 0);
7016 continue;
7017 }
7018
7019 case ADDR_EXPR:
7020 inner = TREE_OPERAND (inner, 0);
7021
7022 while (REFERENCE_CLASS_P (inner)
7023 && TREE_CODE (inner) != INDIRECT_REF)
7024 inner = TREE_OPERAND (inner, 0);
7025
7026 if (DECL_P (inner)
7027 && !DECL_EXTERNAL (inner)
7028 && !TREE_STATIC (inner)
7029 && DECL_CONTEXT (inner) == current_function_decl)
7030 warning (0, "function returns address of local variable");
7031 break;
7032
7033 default:
7034 break;
7035 }
7036
7037 break;
7038 }
7039
7040 retval = build2 (MODIFY_EXPR, TREE_TYPE (res), res, t);
7041 }
7042
7043 ret_stmt = build_stmt (RETURN_EXPR, retval);
7044 TREE_NO_WARNING (ret_stmt) |= no_warning;
7045 return add_stmt (ret_stmt);
7046 }
7047
7048 struct c_switch {
7049 /* The SWITCH_EXPR being built. */
7050 tree switch_expr;
7051
7052 /* The original type of the testing expression, i.e. before the
7053 default conversion is applied. */
7054 tree orig_type;
7055
7056 /* A splay-tree mapping the low element of a case range to the high
7057 element, or NULL_TREE if there is no high element. Used to
7058 determine whether or not a new case label duplicates an old case
7059 label. We need a tree, rather than simply a hash table, because
7060 of the GNU case range extension. */
7061 splay_tree cases;
7062
7063 /* Number of nested statement expressions within this switch
7064 statement; if nonzero, case and default labels may not
7065 appear. */
7066 unsigned int blocked_stmt_expr;
7067
7068 /* Scope of outermost declarations of identifiers with variably
7069 modified type within this switch statement; if nonzero, case and
7070 default labels may not appear. */
7071 unsigned int blocked_vm;
7072
7073 /* The next node on the stack. */
7074 struct c_switch *next;
7075 };
7076
7077 /* A stack of the currently active switch statements. The innermost
7078 switch statement is on the top of the stack. There is no need to
7079 mark the stack for garbage collection because it is only active
7080 during the processing of the body of a function, and we never
7081 collect at that point. */
7082
7083 struct c_switch *c_switch_stack;
7084
7085 /* Start a C switch statement, testing expression EXP. Return the new
7086 SWITCH_EXPR. */
7087
7088 tree
c_start_case(tree exp)7089 c_start_case (tree exp)
7090 {
7091 tree orig_type = error_mark_node;
7092 struct c_switch *cs;
7093
7094 if (exp != error_mark_node)
7095 {
7096 orig_type = TREE_TYPE (exp);
7097
7098 if (!INTEGRAL_TYPE_P (orig_type))
7099 {
7100 if (orig_type != error_mark_node)
7101 {
7102 error ("switch quantity not an integer");
7103 orig_type = error_mark_node;
7104 }
7105 exp = integer_zero_node;
7106 }
7107 else
7108 {
7109 tree type = TYPE_MAIN_VARIANT (orig_type);
7110
7111 if (!in_system_header
7112 && (type == long_integer_type_node
7113 || type == long_unsigned_type_node))
7114 warning (OPT_Wtraditional, "%<long%> switch expression not "
7115 "converted to %<int%> in ISO C");
7116
7117 exp = default_conversion (exp);
7118 }
7119 }
7120
7121 /* Add this new SWITCH_EXPR to the stack. */
7122 cs = XNEW (struct c_switch);
7123 cs->switch_expr = build3 (SWITCH_EXPR, orig_type, exp, NULL_TREE, NULL_TREE);
7124 cs->orig_type = orig_type;
7125 cs->cases = splay_tree_new (case_compare, NULL, NULL);
7126 cs->blocked_stmt_expr = 0;
7127 cs->blocked_vm = 0;
7128 cs->next = c_switch_stack;
7129 c_switch_stack = cs;
7130
7131 return add_stmt (cs->switch_expr);
7132 }
7133
7134 /* Process a case label. */
7135
7136 tree
do_case(tree low_value,tree high_value)7137 do_case (tree low_value, tree high_value)
7138 {
7139 tree label = NULL_TREE;
7140
7141 if (c_switch_stack && !c_switch_stack->blocked_stmt_expr
7142 && !c_switch_stack->blocked_vm)
7143 {
7144 label = c_add_case_label (c_switch_stack->cases,
7145 SWITCH_COND (c_switch_stack->switch_expr),
7146 c_switch_stack->orig_type,
7147 low_value, high_value);
7148 if (label == error_mark_node)
7149 label = NULL_TREE;
7150 }
7151 else if (c_switch_stack && c_switch_stack->blocked_stmt_expr)
7152 {
7153 if (low_value)
7154 error ("case label in statement expression not containing "
7155 "enclosing switch statement");
7156 else
7157 error ("%<default%> label in statement expression not containing "
7158 "enclosing switch statement");
7159 }
7160 else if (c_switch_stack && c_switch_stack->blocked_vm)
7161 {
7162 if (low_value)
7163 error ("case label in scope of identifier with variably modified "
7164 "type not containing enclosing switch statement");
7165 else
7166 error ("%<default%> label in scope of identifier with variably "
7167 "modified type not containing enclosing switch statement");
7168 }
7169 else if (low_value)
7170 error ("case label not within a switch statement");
7171 else
7172 error ("%<default%> label not within a switch statement");
7173
7174 return label;
7175 }
7176
7177 /* Finish the switch statement. */
7178
7179 void
c_finish_case(tree body)7180 c_finish_case (tree body)
7181 {
7182 struct c_switch *cs = c_switch_stack;
7183 location_t switch_location;
7184
7185 SWITCH_BODY (cs->switch_expr) = body;
7186
7187 /* We must not be within a statement expression nested in the switch
7188 at this point; we might, however, be within the scope of an
7189 identifier with variably modified type nested in the switch. */
7190 gcc_assert (!cs->blocked_stmt_expr);
7191
7192 /* Emit warnings as needed. */
7193 if (EXPR_HAS_LOCATION (cs->switch_expr))
7194 switch_location = EXPR_LOCATION (cs->switch_expr);
7195 else
7196 switch_location = input_location;
7197 c_do_switch_warnings (cs->cases, switch_location,
7198 TREE_TYPE (cs->switch_expr),
7199 SWITCH_COND (cs->switch_expr));
7200
7201 /* Pop the stack. */
7202 c_switch_stack = cs->next;
7203 splay_tree_delete (cs->cases);
7204 XDELETE (cs);
7205 }
7206
7207 /* Emit an if statement. IF_LOCUS is the location of the 'if'. COND,
7208 THEN_BLOCK and ELSE_BLOCK are expressions to be used; ELSE_BLOCK
7209 may be null. NESTED_IF is true if THEN_BLOCK contains another IF
7210 statement, and was not surrounded with parenthesis. */
7211
7212 void
c_finish_if_stmt(location_t if_locus,tree cond,tree then_block,tree else_block,bool nested_if)7213 c_finish_if_stmt (location_t if_locus, tree cond, tree then_block,
7214 tree else_block, bool nested_if)
7215 {
7216 tree stmt;
7217
7218 /* Diagnose an ambiguous else if if-then-else is nested inside if-then. */
7219 if (warn_parentheses && nested_if && else_block == NULL)
7220 {
7221 tree inner_if = then_block;
7222
7223 /* We know from the grammar productions that there is an IF nested
7224 within THEN_BLOCK. Due to labels and c99 conditional declarations,
7225 it might not be exactly THEN_BLOCK, but should be the last
7226 non-container statement within. */
7227 while (1)
7228 switch (TREE_CODE (inner_if))
7229 {
7230 case COND_EXPR:
7231 goto found;
7232 case BIND_EXPR:
7233 inner_if = BIND_EXPR_BODY (inner_if);
7234 break;
7235 case STATEMENT_LIST:
7236 inner_if = expr_last (then_block);
7237 break;
7238 case TRY_FINALLY_EXPR:
7239 case TRY_CATCH_EXPR:
7240 inner_if = TREE_OPERAND (inner_if, 0);
7241 break;
7242 default:
7243 gcc_unreachable ();
7244 }
7245 found:
7246
7247 if (COND_EXPR_ELSE (inner_if))
7248 warning (OPT_Wparentheses,
7249 "%Hsuggest explicit braces to avoid ambiguous %<else%>",
7250 &if_locus);
7251 }
7252
7253 empty_body_warning (then_block, else_block);
7254
7255 stmt = build3 (COND_EXPR, void_type_node, cond, then_block, else_block);
7256 SET_EXPR_LOCATION (stmt, if_locus);
7257 add_stmt (stmt);
7258 }
7259
7260 /* APPLE LOCAL begin for-fsf-4_4 3274130 5295549 */ \
7261 /* Emit a general-purpose loop construct. START_LOCUS is the location
7262 of the beginning of the loop. COND is the loop condition.
7263 COND_IS_FIRST is false for DO loops. INCR is the FOR increment
7264 expression. BODY is the statement controlled by the loop. BLAB is
7265 the break label. CLAB is the continue label. ATTRS is the
7266 attributes associated with the loop, which at present are
7267 associated with the topmost label. Everything is allowed to be
7268 NULL. */
7269
7270 /* APPLE LOCAL end for-fsf-4_4 3274130 5295549 */ \
7271 void
c_finish_loop(location_t start_locus,tree cond,tree incr,tree body,tree blab,tree clab,tree attrs,bool cond_is_first)7272 c_finish_loop (location_t start_locus, tree cond, tree incr, tree body,
7273 /* APPLE LOCAL begin for-fsf-4_4 3274130 5295549 */ \
7274 tree blab, tree clab, tree attrs, bool cond_is_first)
7275 /* APPLE LOCAL end for-fsf-4_4 3274130 5295549 */ \
7276 {
7277 tree entry = NULL, exit = NULL, t;
7278
7279 /* If the condition is zero don't generate a loop construct. */
7280 if (cond && integer_zerop (cond))
7281 {
7282 if (cond_is_first)
7283 {
7284 t = build_and_jump (&blab);
7285 SET_EXPR_LOCATION (t, start_locus);
7286 add_stmt (t);
7287 }
7288 }
7289 else
7290 {
7291 tree top = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
7292
7293 /* If we have an exit condition, then we build an IF with gotos either
7294 out of the loop, or to the top of it. If there's no exit condition,
7295 then we just build a jump back to the top. */
7296 exit = build_and_jump (&LABEL_EXPR_LABEL (top));
7297
7298 if (cond && !integer_nonzerop (cond))
7299 {
7300 /* Canonicalize the loop condition to the end. This means
7301 generating a branch to the loop condition. Reuse the
7302 continue label, if possible. */
7303 if (cond_is_first)
7304 {
7305 if (incr || !clab)
7306 {
7307 entry = build1 (LABEL_EXPR, void_type_node, NULL_TREE);
7308 t = build_and_jump (&LABEL_EXPR_LABEL (entry));
7309 }
7310 else
7311 t = build1 (GOTO_EXPR, void_type_node, clab);
7312 SET_EXPR_LOCATION (t, start_locus);
7313 add_stmt (t);
7314 }
7315
7316 t = build_and_jump (&blab);
7317 exit = fold_build3 (COND_EXPR, void_type_node, cond, exit, t);
7318 if (cond_is_first)
7319 SET_EXPR_LOCATION (exit, start_locus);
7320 else
7321 SET_EXPR_LOCATION (exit, input_location);
7322 }
7323
7324 add_stmt (top);
7325 }
7326
7327 if (body)
7328 add_stmt (body);
7329 if (clab)
7330 add_stmt (build1 (LABEL_EXPR, void_type_node, clab));
7331 if (incr)
7332 add_stmt (incr);
7333 if (entry)
7334 add_stmt (entry);
7335 if (exit)
7336 add_stmt (exit);
7337 if (blab)
7338 add_stmt (build1 (LABEL_EXPR, void_type_node, blab));
7339 }
7340
7341 tree
c_finish_bc_stmt(tree * label_p,bool is_break)7342 c_finish_bc_stmt (tree *label_p, bool is_break)
7343 {
7344 bool skip;
7345 tree label = *label_p;
7346
7347 /* In switch statements break is sometimes stylistically used after
7348 a return statement. This can lead to spurious warnings about
7349 control reaching the end of a non-void function when it is
7350 inlined. Note that we are calling block_may_fallthru with
7351 language specific tree nodes; this works because
7352 block_may_fallthru returns true when given something it does not
7353 understand. */
7354 skip = !block_may_fallthru (cur_stmt_list);
7355
7356 if (!label)
7357 {
7358 if (!skip)
7359 *label_p = label = create_artificial_label ();
7360 }
7361 else if (TREE_CODE (label) == LABEL_DECL)
7362 ;
7363 else switch (TREE_INT_CST_LOW (label))
7364 {
7365 case 0:
7366 if (is_break)
7367 error ("break statement not within loop or switch");
7368 else
7369 error ("continue statement not within a loop");
7370 return NULL_TREE;
7371
7372 case 1:
7373 gcc_assert (is_break);
7374 error ("break statement used with OpenMP for loop");
7375 return NULL_TREE;
7376
7377 default:
7378 gcc_unreachable ();
7379 }
7380
7381 if (skip)
7382 return NULL_TREE;
7383
7384 return add_stmt (build1 (GOTO_EXPR, void_type_node, label));
7385 }
7386
7387 /* A helper routine for c_process_expr_stmt and c_finish_stmt_expr. */
7388
7389 static void
emit_side_effect_warnings(tree expr)7390 emit_side_effect_warnings (tree expr)
7391 {
7392 if (expr == error_mark_node)
7393 ;
7394 else if (!TREE_SIDE_EFFECTS (expr))
7395 {
7396 if (!VOID_TYPE_P (TREE_TYPE (expr)) && !TREE_NO_WARNING (expr))
7397 warning (0, "%Hstatement with no effect",
7398 EXPR_HAS_LOCATION (expr) ? EXPR_LOCUS (expr) : &input_location);
7399 }
7400 else if (warn_unused_value)
7401 warn_if_unused_value (expr, input_location);
7402 }
7403
7404 /* Process an expression as if it were a complete statement. Emit
7405 diagnostics, but do not call ADD_STMT. */
7406
7407 tree
c_process_expr_stmt(tree expr)7408 c_process_expr_stmt (tree expr)
7409 {
7410 if (!expr)
7411 return NULL_TREE;
7412
7413 if (warn_sequence_point)
7414 verify_sequence_points (expr);
7415
7416 if (TREE_TYPE (expr) != error_mark_node
7417 && !COMPLETE_OR_VOID_TYPE_P (TREE_TYPE (expr))
7418 && TREE_CODE (TREE_TYPE (expr)) != ARRAY_TYPE)
7419 error ("expression statement has incomplete type");
7420
7421 /* If we're not processing a statement expression, warn about unused values.
7422 Warnings for statement expressions will be emitted later, once we figure
7423 out which is the result. */
7424 if (!STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7425 && (extra_warnings || warn_unused_value))
7426 emit_side_effect_warnings (expr);
7427
7428 /* If the expression is not of a type to which we cannot assign a line
7429 number, wrap the thing in a no-op NOP_EXPR. */
7430 if (DECL_P (expr) || CONSTANT_CLASS_P (expr))
7431 expr = build1 (NOP_EXPR, TREE_TYPE (expr), expr);
7432
7433 if (EXPR_P (expr))
7434 SET_EXPR_LOCATION (expr, input_location);
7435
7436 return expr;
7437 }
7438
7439 /* Emit an expression as a statement. */
7440
7441 tree
c_finish_expr_stmt(tree expr)7442 c_finish_expr_stmt (tree expr)
7443 {
7444 if (expr)
7445 return add_stmt (c_process_expr_stmt (expr));
7446 else
7447 return NULL;
7448 }
7449
7450 /* Do the opposite and emit a statement as an expression. To begin,
7451 create a new binding level and return it. */
7452
7453 tree
c_begin_stmt_expr(void)7454 c_begin_stmt_expr (void)
7455 {
7456 tree ret;
7457 struct c_label_context_se *nstack;
7458 struct c_label_list *glist;
7459
7460 /* We must force a BLOCK for this level so that, if it is not expanded
7461 later, there is a way to turn off the entire subtree of blocks that
7462 are contained in it. */
7463 keep_next_level ();
7464 ret = c_begin_compound_stmt (true);
7465 if (c_switch_stack)
7466 {
7467 c_switch_stack->blocked_stmt_expr++;
7468 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7469 }
7470 for (glist = label_context_stack_se->labels_used;
7471 glist != NULL;
7472 glist = glist->next)
7473 {
7474 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 1;
7475 }
7476 nstack = XOBNEW (&parser_obstack, struct c_label_context_se);
7477 nstack->labels_def = NULL;
7478 nstack->labels_used = NULL;
7479 nstack->next = label_context_stack_se;
7480 label_context_stack_se = nstack;
7481
7482 /* Mark the current statement list as belonging to a statement list. */
7483 STATEMENT_LIST_STMT_EXPR (ret) = 1;
7484
7485 return ret;
7486 }
7487
7488 tree
c_finish_stmt_expr(tree body)7489 c_finish_stmt_expr (tree body)
7490 {
7491 tree last, type, tmp, val;
7492 tree *last_p;
7493 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7494
7495 body = c_end_compound_stmt (body, true);
7496 if (c_switch_stack)
7497 {
7498 gcc_assert (c_switch_stack->blocked_stmt_expr != 0);
7499 c_switch_stack->blocked_stmt_expr--;
7500 }
7501 /* It is no longer possible to jump to labels defined within this
7502 statement expression. */
7503 for (dlist = label_context_stack_se->labels_def;
7504 dlist != NULL;
7505 dlist = dlist->next)
7506 {
7507 C_DECL_UNJUMPABLE_STMT_EXPR (dlist->label) = 1;
7508 }
7509 /* It is again possible to define labels with a goto just outside
7510 this statement expression. */
7511 for (glist = label_context_stack_se->next->labels_used;
7512 glist != NULL;
7513 glist = glist->next)
7514 {
7515 C_DECL_UNDEFINABLE_STMT_EXPR (glist->label) = 0;
7516 glist_prev = glist;
7517 }
7518 if (glist_prev != NULL)
7519 glist_prev->next = label_context_stack_se->labels_used;
7520 else
7521 label_context_stack_se->next->labels_used
7522 = label_context_stack_se->labels_used;
7523 label_context_stack_se = label_context_stack_se->next;
7524
7525 /* Locate the last statement in BODY. See c_end_compound_stmt
7526 about always returning a BIND_EXPR. */
7527 last_p = &BIND_EXPR_BODY (body);
7528 last = BIND_EXPR_BODY (body);
7529
7530 continue_searching:
7531 if (TREE_CODE (last) == STATEMENT_LIST)
7532 {
7533 tree_stmt_iterator i;
7534
7535 /* This can happen with degenerate cases like ({ }). No value. */
7536 if (!TREE_SIDE_EFFECTS (last))
7537 return body;
7538
7539 /* If we're supposed to generate side effects warnings, process
7540 all of the statements except the last. */
7541 if (extra_warnings || warn_unused_value)
7542 {
7543 for (i = tsi_start (last); !tsi_one_before_end_p (i); tsi_next (&i))
7544 emit_side_effect_warnings (tsi_stmt (i));
7545 }
7546 else
7547 i = tsi_last (last);
7548 last_p = tsi_stmt_ptr (i);
7549 last = *last_p;
7550 }
7551
7552 /* If the end of the list is exception related, then the list was split
7553 by a call to push_cleanup. Continue searching. */
7554 if (TREE_CODE (last) == TRY_FINALLY_EXPR
7555 || TREE_CODE (last) == TRY_CATCH_EXPR)
7556 {
7557 last_p = &TREE_OPERAND (last, 0);
7558 last = *last_p;
7559 goto continue_searching;
7560 }
7561
7562 /* In the case that the BIND_EXPR is not necessary, return the
7563 expression out from inside it. */
7564 if (last == error_mark_node
7565 || (last == BIND_EXPR_BODY (body)
7566 && BIND_EXPR_VARS (body) == NULL))
7567 {
7568 /* Do not warn if the return value of a statement expression is
7569 unused. */
7570 if (EXPR_P (last))
7571 TREE_NO_WARNING (last) = 1;
7572 return last;
7573 }
7574
7575 /* Extract the type of said expression. */
7576 type = TREE_TYPE (last);
7577
7578 /* If we're not returning a value at all, then the BIND_EXPR that
7579 we already have is a fine expression to return. */
7580 if (!type || VOID_TYPE_P (type))
7581 return body;
7582
7583 /* Now that we've located the expression containing the value, it seems
7584 silly to make voidify_wrapper_expr repeat the process. Create a
7585 temporary of the appropriate type and stick it in a TARGET_EXPR. */
7586 tmp = create_tmp_var_raw (type, NULL);
7587
7588 /* Unwrap a no-op NOP_EXPR as added by c_finish_expr_stmt. This avoids
7589 tree_expr_nonnegative_p giving up immediately. */
7590 val = last;
7591 if (TREE_CODE (val) == NOP_EXPR
7592 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0)))
7593 val = TREE_OPERAND (val, 0);
7594
7595 *last_p = build2 (MODIFY_EXPR, void_type_node, tmp, val);
7596 SET_EXPR_LOCUS (*last_p, EXPR_LOCUS (last));
7597
7598 return build4 (TARGET_EXPR, type, tmp, body, NULL_TREE, NULL_TREE);
7599 }
7600
7601 /* Begin the scope of an identifier of variably modified type, scope
7602 number SCOPE. Jumping from outside this scope to inside it is not
7603 permitted. */
7604
7605 void
c_begin_vm_scope(unsigned int scope)7606 c_begin_vm_scope (unsigned int scope)
7607 {
7608 struct c_label_context_vm *nstack;
7609 struct c_label_list *glist;
7610
7611 gcc_assert (scope > 0);
7612
7613 /* At file_scope, we don't have to do any processing. */
7614 if (label_context_stack_vm == NULL)
7615 return;
7616
7617 if (c_switch_stack && !c_switch_stack->blocked_vm)
7618 c_switch_stack->blocked_vm = scope;
7619 for (glist = label_context_stack_vm->labels_used;
7620 glist != NULL;
7621 glist = glist->next)
7622 {
7623 C_DECL_UNDEFINABLE_VM (glist->label) = 1;
7624 }
7625 nstack = XOBNEW (&parser_obstack, struct c_label_context_vm);
7626 nstack->labels_def = NULL;
7627 nstack->labels_used = NULL;
7628 nstack->scope = scope;
7629 nstack->next = label_context_stack_vm;
7630 label_context_stack_vm = nstack;
7631 }
7632
7633 /* End a scope which may contain identifiers of variably modified
7634 type, scope number SCOPE. */
7635
7636 void
c_end_vm_scope(unsigned int scope)7637 c_end_vm_scope (unsigned int scope)
7638 {
7639 if (label_context_stack_vm == NULL)
7640 return;
7641 if (c_switch_stack && c_switch_stack->blocked_vm == scope)
7642 c_switch_stack->blocked_vm = 0;
7643 /* We may have a number of nested scopes of identifiers with
7644 variably modified type, all at this depth. Pop each in turn. */
7645 while (label_context_stack_vm->scope == scope)
7646 {
7647 struct c_label_list *dlist, *glist, *glist_prev = NULL;
7648
7649 /* It is no longer possible to jump to labels defined within this
7650 scope. */
7651 for (dlist = label_context_stack_vm->labels_def;
7652 dlist != NULL;
7653 dlist = dlist->next)
7654 {
7655 C_DECL_UNJUMPABLE_VM (dlist->label) = 1;
7656 }
7657 /* It is again possible to define labels with a goto just outside
7658 this scope. */
7659 for (glist = label_context_stack_vm->next->labels_used;
7660 glist != NULL;
7661 glist = glist->next)
7662 {
7663 C_DECL_UNDEFINABLE_VM (glist->label) = 0;
7664 glist_prev = glist;
7665 }
7666 if (glist_prev != NULL)
7667 glist_prev->next = label_context_stack_vm->labels_used;
7668 else
7669 label_context_stack_vm->next->labels_used
7670 = label_context_stack_vm->labels_used;
7671 label_context_stack_vm = label_context_stack_vm->next;
7672 }
7673 }
7674
7675 /* Begin and end compound statements. This is as simple as pushing
7676 and popping new statement lists from the tree. */
7677
7678 tree
c_begin_compound_stmt(bool do_scope)7679 c_begin_compound_stmt (bool do_scope)
7680 {
7681 tree stmt = push_stmt_list ();
7682 if (do_scope)
7683 push_scope ();
7684 return stmt;
7685 }
7686
7687 tree
c_end_compound_stmt(tree stmt,bool do_scope)7688 c_end_compound_stmt (tree stmt, bool do_scope)
7689 {
7690 tree block = NULL;
7691
7692 if (do_scope)
7693 {
7694 if (c_dialect_objc ())
7695 objc_clear_super_receiver ();
7696 block = pop_scope ();
7697 }
7698
7699 stmt = pop_stmt_list (stmt);
7700 stmt = c_build_bind_expr (block, stmt);
7701
7702 /* If this compound statement is nested immediately inside a statement
7703 expression, then force a BIND_EXPR to be created. Otherwise we'll
7704 do the wrong thing for ({ { 1; } }) or ({ 1; { } }). In particular,
7705 STATEMENT_LISTs merge, and thus we can lose track of what statement
7706 was really last. */
7707 if (cur_stmt_list
7708 && STATEMENT_LIST_STMT_EXPR (cur_stmt_list)
7709 && TREE_CODE (stmt) != BIND_EXPR)
7710 {
7711 stmt = build3 (BIND_EXPR, void_type_node, NULL, stmt, NULL);
7712 TREE_SIDE_EFFECTS (stmt) = 1;
7713 }
7714
7715 return stmt;
7716 }
7717
7718 /* Queue a cleanup. CLEANUP is an expression/statement to be executed
7719 when the current scope is exited. EH_ONLY is true when this is not
7720 meant to apply to normal control flow transfer. */
7721
7722 void
push_cleanup(tree ARG_UNUSED (decl),tree cleanup,bool eh_only)7723 push_cleanup (tree ARG_UNUSED (decl), tree cleanup, bool eh_only)
7724 {
7725 enum tree_code code;
7726 tree stmt, list;
7727 bool stmt_expr;
7728
7729 code = eh_only ? TRY_CATCH_EXPR : TRY_FINALLY_EXPR;
7730 stmt = build_stmt (code, NULL, cleanup);
7731 add_stmt (stmt);
7732 stmt_expr = STATEMENT_LIST_STMT_EXPR (cur_stmt_list);
7733 list = push_stmt_list ();
7734 TREE_OPERAND (stmt, 0) = list;
7735 STATEMENT_LIST_STMT_EXPR (list) = stmt_expr;
7736 }
7737
7738 /* Build a binary-operation expression without default conversions.
7739 CODE is the kind of expression to build.
7740 This function differs from `build' in several ways:
7741 the data type of the result is computed and recorded in it,
7742 warnings are generated if arg data types are invalid,
7743 special handling for addition and subtraction of pointers is known,
7744 and some optimization is done (operations on narrow ints
7745 are done in the narrower type when that gives the same result).
7746 Constant folding is also done before the result is returned.
7747
7748 Note that the operands will never have enumeral types, or function
7749 or array types, because either they will have the default conversions
7750 performed or they have both just been converted to some other type in which
7751 the arithmetic is to be done. */
7752
7753 tree
build_binary_op(enum tree_code code,tree orig_op0,tree orig_op1,int convert_p)7754 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
7755 int convert_p)
7756 {
7757 tree type0, type1;
7758 enum tree_code code0, code1;
7759 tree op0, op1;
7760 const char *invalid_op_diag;
7761
7762 /* Expression code to give to the expression when it is built.
7763 Normally this is CODE, which is what the caller asked for,
7764 but in some special cases we change it. */
7765 enum tree_code resultcode = code;
7766
7767 /* Data type in which the computation is to be performed.
7768 In the simplest cases this is the common type of the arguments. */
7769 tree result_type = NULL;
7770
7771 /* Nonzero means operands have already been type-converted
7772 in whatever way is necessary.
7773 Zero means they need to be converted to RESULT_TYPE. */
7774 int converted = 0;
7775
7776 /* Nonzero means create the expression with this type, rather than
7777 RESULT_TYPE. */
7778 tree build_type = 0;
7779
7780 /* Nonzero means after finally constructing the expression
7781 convert it to this type. */
7782 tree final_type = 0;
7783
7784 /* Nonzero if this is an operation like MIN or MAX which can
7785 safely be computed in short if both args are promoted shorts.
7786 Also implies COMMON.
7787 -1 indicates a bitwise operation; this makes a difference
7788 in the exact conditions for when it is safe to do the operation
7789 in a narrower mode. */
7790 int shorten = 0;
7791
7792 /* Nonzero if this is a comparison operation;
7793 if both args are promoted shorts, compare the original shorts.
7794 Also implies COMMON. */
7795 int short_compare = 0;
7796
7797 /* Nonzero if this is a right-shift operation, which can be computed on the
7798 original short and then promoted if the operand is a promoted short. */
7799 int short_shift = 0;
7800
7801 /* Nonzero means set RESULT_TYPE to the common type of the args. */
7802 int common = 0;
7803
7804 /* True means types are compatible as far as ObjC is concerned. */
7805 bool objc_ok;
7806
7807 if (convert_p)
7808 {
7809 op0 = default_conversion (orig_op0);
7810 op1 = default_conversion (orig_op1);
7811 }
7812 else
7813 {
7814 op0 = orig_op0;
7815 op1 = orig_op1;
7816 }
7817
7818 type0 = TREE_TYPE (op0);
7819 type1 = TREE_TYPE (op1);
7820
7821 /* The expression codes of the data types of the arguments tell us
7822 whether the arguments are integers, floating, pointers, etc. */
7823 code0 = TREE_CODE (type0);
7824 code1 = TREE_CODE (type1);
7825
7826 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
7827 STRIP_TYPE_NOPS (op0);
7828 STRIP_TYPE_NOPS (op1);
7829
7830 /* If an error was already reported for one of the arguments,
7831 avoid reporting another error. */
7832
7833 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
7834 return error_mark_node;
7835
7836 if ((invalid_op_diag
7837 = targetm.invalid_binary_op (code, type0, type1)))
7838 {
7839 error (invalid_op_diag, "");
7840 return error_mark_node;
7841 }
7842
7843 objc_ok = objc_compare_types (type0, type1, -3, NULL_TREE);
7844
7845 switch (code)
7846 {
7847 case PLUS_EXPR:
7848 /* Handle the pointer + int case. */
7849 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7850 return pointer_int_sum (PLUS_EXPR, op0, op1);
7851 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
7852 return pointer_int_sum (PLUS_EXPR, op1, op0);
7853 else
7854 common = 1;
7855 break;
7856
7857 case MINUS_EXPR:
7858 /* Subtraction of two similar pointers.
7859 We must subtract them as integers, then divide by object size. */
7860 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
7861 && comp_target_types (type0, type1))
7862 return pointer_diff (op0, op1);
7863 /* Handle pointer minus int. Just like pointer plus int. */
7864 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
7865 return pointer_int_sum (MINUS_EXPR, op0, op1);
7866 else
7867 common = 1;
7868 break;
7869
7870 case MULT_EXPR:
7871 common = 1;
7872 break;
7873
7874 case TRUNC_DIV_EXPR:
7875 case CEIL_DIV_EXPR:
7876 case FLOOR_DIV_EXPR:
7877 case ROUND_DIV_EXPR:
7878 case EXACT_DIV_EXPR:
7879 /* Floating point division by zero is a legitimate way to obtain
7880 infinities and NaNs. */
7881 if (skip_evaluation == 0 && integer_zerop (op1))
7882 warning (OPT_Wdiv_by_zero, "division by zero");
7883
7884 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
7885 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7886 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
7887 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
7888 {
7889 enum tree_code tcode0 = code0, tcode1 = code1;
7890
7891 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
7892 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
7893 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
7894 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
7895
7896 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
7897 resultcode = RDIV_EXPR;
7898 else
7899 /* Although it would be tempting to shorten always here, that
7900 loses on some targets, since the modulo instruction is
7901 undefined if the quotient can't be represented in the
7902 computation mode. We shorten only if unsigned or if
7903 dividing by something we know != -1. */
7904 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7905 || (TREE_CODE (op1) == INTEGER_CST
7906 && !integer_all_onesp (op1)));
7907 common = 1;
7908 }
7909 break;
7910
7911 case BIT_AND_EXPR:
7912 case BIT_IOR_EXPR:
7913 case BIT_XOR_EXPR:
7914 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7915 shorten = -1;
7916 else if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
7917 common = 1;
7918 break;
7919
7920 case TRUNC_MOD_EXPR:
7921 case FLOOR_MOD_EXPR:
7922 if (skip_evaluation == 0 && integer_zerop (op1))
7923 warning (OPT_Wdiv_by_zero, "division by zero");
7924
7925 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7926 {
7927 /* Although it would be tempting to shorten always here, that loses
7928 on some targets, since the modulo instruction is undefined if the
7929 quotient can't be represented in the computation mode. We shorten
7930 only if unsigned or if dividing by something we know != -1. */
7931 shorten = (TYPE_UNSIGNED (TREE_TYPE (orig_op0))
7932 || (TREE_CODE (op1) == INTEGER_CST
7933 && !integer_all_onesp (op1)));
7934 common = 1;
7935 }
7936 break;
7937
7938 case TRUTH_ANDIF_EXPR:
7939 case TRUTH_ORIF_EXPR:
7940 case TRUTH_AND_EXPR:
7941 case TRUTH_OR_EXPR:
7942 case TRUTH_XOR_EXPR:
7943 if ((code0 == INTEGER_TYPE || code0 == POINTER_TYPE
7944 || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
7945 && (code1 == INTEGER_TYPE || code1 == POINTER_TYPE
7946 || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
7947 {
7948 /* Result of these operations is always an int,
7949 but that does not mean the operands should be
7950 converted to ints! */
7951 result_type = integer_type_node;
7952 op0 = c_common_truthvalue_conversion (op0);
7953 op1 = c_common_truthvalue_conversion (op1);
7954 converted = 1;
7955 }
7956 break;
7957
7958 /* Shift operations: result has same type as first operand;
7959 always convert second operand to int.
7960 Also set SHORT_SHIFT if shifting rightward. */
7961
7962 case RSHIFT_EXPR:
7963 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7964 {
7965 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7966 {
7967 if (tree_int_cst_sgn (op1) < 0)
7968 warning (0, "right shift count is negative");
7969 else
7970 {
7971 if (!integer_zerop (op1))
7972 short_shift = 1;
7973
7974 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7975 warning (0, "right shift count >= width of type");
7976 }
7977 }
7978
7979 /* Use the type of the value to be shifted. */
7980 result_type = type0;
7981 /* Convert the shift-count to an integer, regardless of size
7982 of value being shifted. */
7983 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
7984 op1 = convert (integer_type_node, op1);
7985 /* Avoid converting op1 to result_type later. */
7986 converted = 1;
7987 }
7988 break;
7989
7990 case LSHIFT_EXPR:
7991 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
7992 {
7993 if (TREE_CODE (op1) == INTEGER_CST && skip_evaluation == 0)
7994 {
7995 if (tree_int_cst_sgn (op1) < 0)
7996 warning (0, "left shift count is negative");
7997
7998 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
7999 warning (0, "left shift count >= width of type");
8000 }
8001
8002 /* Use the type of the value to be shifted. */
8003 result_type = type0;
8004 /* Convert the shift-count to an integer, regardless of size
8005 of value being shifted. */
8006 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
8007 op1 = convert (integer_type_node, op1);
8008 /* Avoid converting op1 to result_type later. */
8009 converted = 1;
8010 }
8011 break;
8012
8013 case EQ_EXPR:
8014 case NE_EXPR:
8015 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
8016 warning (OPT_Wfloat_equal,
8017 "comparing floating point with == or != is unsafe");
8018 /* Result of comparison is always int,
8019 but don't convert the args to int! */
8020 build_type = integer_type_node;
8021 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
8022 || code0 == COMPLEX_TYPE)
8023 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
8024 || code1 == COMPLEX_TYPE))
8025 short_compare = 1;
8026 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
8027 {
8028 tree tt0 = TREE_TYPE (type0);
8029 tree tt1 = TREE_TYPE (type1);
8030 /* Anything compares with void *. void * compares with anything.
8031 Otherwise, the targets must be compatible
8032 and both must be object or both incomplete. */
8033 if (comp_target_types (type0, type1))
8034 result_type = common_pointer_type (type0, type1);
8035 else if (VOID_TYPE_P (tt0))
8036 {
8037 /* op0 != orig_op0 detects the case of something
8038 whose value is 0 but which isn't a valid null ptr const. */
8039 if (pedantic && !null_pointer_constant_p (orig_op0)
8040 && TREE_CODE (tt1) == FUNCTION_TYPE)
8041 pedwarn ("ISO C forbids comparison of %<void *%>"
8042 " with function pointer");
8043 }
8044 else if (VOID_TYPE_P (tt1))
8045 {
8046 if (pedantic && !null_pointer_constant_p (orig_op1)
8047 && TREE_CODE (tt0) == FUNCTION_TYPE)
8048 pedwarn ("ISO C forbids comparison of %<void *%>"
8049 " with function pointer");
8050 }
8051 else
8052 /* Avoid warning about the volatile ObjC EH puts on decls. */
8053 if (!objc_ok)
8054 pedwarn ("comparison of distinct pointer types lacks a cast");
8055
8056 if (result_type == NULL_TREE)
8057 result_type = ptr_type_node;
8058 }
8059 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
8060 {
8061 if (TREE_CODE (op0) == ADDR_EXPR
8062 && DECL_P (TREE_OPERAND (op0, 0))
8063 && (TREE_CODE (TREE_OPERAND (op0, 0)) == PARM_DECL
8064 || TREE_CODE (TREE_OPERAND (op0, 0)) == LABEL_DECL
8065 || !DECL_WEAK (TREE_OPERAND (op0, 0))))
8066 warning (OPT_Waddress, "the address of %qD will never be NULL",
8067 TREE_OPERAND (op0, 0));
8068 result_type = type0;
8069 }
8070 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
8071 {
8072 if (TREE_CODE (op1) == ADDR_EXPR
8073 && DECL_P (TREE_OPERAND (op1, 0))
8074 && (TREE_CODE (TREE_OPERAND (op1, 0)) == PARM_DECL
8075 || TREE_CODE (TREE_OPERAND (op1, 0)) == LABEL_DECL
8076 || !DECL_WEAK (TREE_OPERAND (op1, 0))))
8077 warning (OPT_Waddress, "the address of %qD will never be NULL",
8078 TREE_OPERAND (op1, 0));
8079 result_type = type1;
8080 }
8081 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
8082 {
8083 result_type = type0;
8084 pedwarn ("comparison between pointer and integer");
8085 }
8086 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
8087 {
8088 result_type = type1;
8089 pedwarn ("comparison between pointer and integer");
8090 }
8091 break;
8092
8093 case LE_EXPR:
8094 case GE_EXPR:
8095 case LT_EXPR:
8096 case GT_EXPR:
8097 build_type = integer_type_node;
8098 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
8099 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
8100 short_compare = 1;
8101 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
8102 {
8103 if (comp_target_types (type0, type1))
8104 {
8105 result_type = common_pointer_type (type0, type1);
8106 if (!COMPLETE_TYPE_P (TREE_TYPE (type0))
8107 != !COMPLETE_TYPE_P (TREE_TYPE (type1)))
8108 pedwarn ("comparison of complete and incomplete pointers");
8109 else if (pedantic
8110 && TREE_CODE (TREE_TYPE (type0)) == FUNCTION_TYPE)
8111 pedwarn ("ISO C forbids ordered comparisons of pointers to functions");
8112 }
8113 else
8114 {
8115 result_type = ptr_type_node;
8116 pedwarn ("comparison of distinct pointer types lacks a cast");
8117 }
8118 }
8119 else if (code0 == POINTER_TYPE && null_pointer_constant_p (orig_op1))
8120 {
8121 result_type = type0;
8122 if (pedantic || extra_warnings)
8123 pedwarn ("ordered comparison of pointer with integer zero");
8124 }
8125 else if (code1 == POINTER_TYPE && null_pointer_constant_p (orig_op0))
8126 {
8127 result_type = type1;
8128 if (pedantic)
8129 pedwarn ("ordered comparison of pointer with integer zero");
8130 }
8131 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
8132 {
8133 result_type = type0;
8134 pedwarn ("comparison between pointer and integer");
8135 }
8136 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
8137 {
8138 result_type = type1;
8139 pedwarn ("comparison between pointer and integer");
8140 }
8141 break;
8142
8143 default:
8144 gcc_unreachable ();
8145 }
8146
8147 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
8148 return error_mark_node;
8149
8150 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
8151 && (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
8152 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
8153 TREE_TYPE (type1))))
8154 {
8155 binary_op_error (code, type0, type1);
8156 return error_mark_node;
8157 }
8158
8159 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
8160 || code0 == VECTOR_TYPE)
8161 &&
8162 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE
8163 || code1 == VECTOR_TYPE))
8164 {
8165 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
8166
8167 if (shorten || common || short_compare)
8168 result_type = c_common_type (type0, type1);
8169
8170 /* For certain operations (which identify themselves by shorten != 0)
8171 if both args were extended from the same smaller type,
8172 do the arithmetic in that type and then extend.
8173
8174 shorten !=0 and !=1 indicates a bitwise operation.
8175 For them, this optimization is safe only if
8176 both args are zero-extended or both are sign-extended.
8177 Otherwise, we might change the result.
8178 Eg, (short)-1 | (unsigned short)-1 is (int)-1
8179 but calculated in (unsigned short) it would be (unsigned short)-1. */
8180
8181 if (shorten && none_complex)
8182 {
8183 int unsigned0, unsigned1;
8184 tree arg0, arg1;
8185 int uns;
8186 tree type;
8187
8188 /* Cast OP0 and OP1 to RESULT_TYPE. Doing so prevents
8189 excessive narrowing when we call get_narrower below. For
8190 example, suppose that OP0 is of unsigned int extended
8191 from signed char and that RESULT_TYPE is long long int.
8192 If we explicitly cast OP0 to RESULT_TYPE, OP0 would look
8193 like
8194
8195 (long long int) (unsigned int) signed_char
8196
8197 which get_narrower would narrow down to
8198
8199 (unsigned int) signed char
8200
8201 If we do not cast OP0 first, get_narrower would return
8202 signed_char, which is inconsistent with the case of the
8203 explicit cast. */
8204 op0 = convert (result_type, op0);
8205 op1 = convert (result_type, op1);
8206
8207 arg0 = get_narrower (op0, &unsigned0);
8208 arg1 = get_narrower (op1, &unsigned1);
8209
8210 /* UNS is 1 if the operation to be done is an unsigned one. */
8211 uns = TYPE_UNSIGNED (result_type);
8212
8213 final_type = result_type;
8214
8215 /* Handle the case that OP0 (or OP1) does not *contain* a conversion
8216 but it *requires* conversion to FINAL_TYPE. */
8217
8218 if ((TYPE_PRECISION (TREE_TYPE (op0))
8219 == TYPE_PRECISION (TREE_TYPE (arg0)))
8220 && TREE_TYPE (op0) != final_type)
8221 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
8222 if ((TYPE_PRECISION (TREE_TYPE (op1))
8223 == TYPE_PRECISION (TREE_TYPE (arg1)))
8224 && TREE_TYPE (op1) != final_type)
8225 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
8226
8227 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
8228
8229 /* For bitwise operations, signedness of nominal type
8230 does not matter. Consider only how operands were extended. */
8231 if (shorten == -1)
8232 uns = unsigned0;
8233
8234 /* Note that in all three cases below we refrain from optimizing
8235 an unsigned operation on sign-extended args.
8236 That would not be valid. */
8237
8238 /* Both args variable: if both extended in same way
8239 from same width, do it in that width.
8240 Do it unsigned if args were zero-extended. */
8241 if ((TYPE_PRECISION (TREE_TYPE (arg0))
8242 < TYPE_PRECISION (result_type))
8243 && (TYPE_PRECISION (TREE_TYPE (arg1))
8244 == TYPE_PRECISION (TREE_TYPE (arg0)))
8245 && unsigned0 == unsigned1
8246 && (unsigned0 || !uns))
8247 result_type
8248 = c_common_signed_or_unsigned_type
8249 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
8250 else if (TREE_CODE (arg0) == INTEGER_CST
8251 && (unsigned1 || !uns)
8252 && (TYPE_PRECISION (TREE_TYPE (arg1))
8253 < TYPE_PRECISION (result_type))
8254 && (type
8255 = c_common_signed_or_unsigned_type (unsigned1,
8256 TREE_TYPE (arg1)),
8257 int_fits_type_p (arg0, type)))
8258 result_type = type;
8259 else if (TREE_CODE (arg1) == INTEGER_CST
8260 && (unsigned0 || !uns)
8261 && (TYPE_PRECISION (TREE_TYPE (arg0))
8262 < TYPE_PRECISION (result_type))
8263 && (type
8264 = c_common_signed_or_unsigned_type (unsigned0,
8265 TREE_TYPE (arg0)),
8266 int_fits_type_p (arg1, type)))
8267 result_type = type;
8268 }
8269
8270 /* Shifts can be shortened if shifting right. */
8271
8272 if (short_shift)
8273 {
8274 int unsigned_arg;
8275 tree arg0 = get_narrower (op0, &unsigned_arg);
8276
8277 final_type = result_type;
8278
8279 if (arg0 == op0 && final_type == TREE_TYPE (op0))
8280 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
8281
8282 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
8283 /* We can shorten only if the shift count is less than the
8284 number of bits in the smaller type size. */
8285 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
8286 /* We cannot drop an unsigned shift after sign-extension. */
8287 && (!TYPE_UNSIGNED (final_type) || unsigned_arg))
8288 {
8289 /* Do an unsigned shift if the operand was zero-extended. */
8290 result_type
8291 = c_common_signed_or_unsigned_type (unsigned_arg,
8292 TREE_TYPE (arg0));
8293 /* Convert value-to-be-shifted to that type. */
8294 if (TREE_TYPE (op0) != result_type)
8295 op0 = convert (result_type, op0);
8296 converted = 1;
8297 }
8298 }
8299
8300 /* Comparison operations are shortened too but differently.
8301 They identify themselves by setting short_compare = 1. */
8302
8303 if (short_compare)
8304 {
8305 /* Don't write &op0, etc., because that would prevent op0
8306 from being kept in a register.
8307 Instead, make copies of the our local variables and
8308 pass the copies by reference, then copy them back afterward. */
8309 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
8310 enum tree_code xresultcode = resultcode;
8311 tree val
8312 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
8313
8314 if (val != 0)
8315 return val;
8316
8317 op0 = xop0, op1 = xop1;
8318 converted = 1;
8319 resultcode = xresultcode;
8320
8321 if (warn_sign_compare && skip_evaluation == 0)
8322 {
8323 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
8324 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
8325 int unsignedp0, unsignedp1;
8326 tree primop0 = get_narrower (op0, &unsignedp0);
8327 tree primop1 = get_narrower (op1, &unsignedp1);
8328
8329 xop0 = orig_op0;
8330 xop1 = orig_op1;
8331 STRIP_TYPE_NOPS (xop0);
8332 STRIP_TYPE_NOPS (xop1);
8333
8334 /* Give warnings for comparisons between signed and unsigned
8335 quantities that may fail.
8336
8337 Do the checking based on the original operand trees, so that
8338 casts will be considered, but default promotions won't be.
8339
8340 Do not warn if the comparison is being done in a signed type,
8341 since the signed type will only be chosen if it can represent
8342 all the values of the unsigned type. */
8343 if (!TYPE_UNSIGNED (result_type))
8344 /* OK */;
8345 /* Do not warn if both operands are the same signedness. */
8346 else if (op0_signed == op1_signed)
8347 /* OK */;
8348 else
8349 {
8350 tree sop, uop;
8351 bool ovf;
8352
8353 if (op0_signed)
8354 sop = xop0, uop = xop1;
8355 else
8356 sop = xop1, uop = xop0;
8357
8358 /* Do not warn if the signed quantity is an
8359 unsuffixed integer literal (or some static
8360 constant expression involving such literals or a
8361 conditional expression involving such literals)
8362 and it is non-negative. */
8363 if (tree_expr_nonnegative_warnv_p (sop, &ovf))
8364 /* OK */;
8365 /* Do not warn if the comparison is an equality operation,
8366 the unsigned quantity is an integral constant, and it
8367 would fit in the result if the result were signed. */
8368 else if (TREE_CODE (uop) == INTEGER_CST
8369 && (resultcode == EQ_EXPR || resultcode == NE_EXPR)
8370 && int_fits_type_p
8371 (uop, c_common_signed_type (result_type)))
8372 /* OK */;
8373 /* Do not warn if the unsigned quantity is an enumeration
8374 constant and its maximum value would fit in the result
8375 if the result were signed. */
8376 else if (TREE_CODE (uop) == INTEGER_CST
8377 && TREE_CODE (TREE_TYPE (uop)) == ENUMERAL_TYPE
8378 && int_fits_type_p
8379 (TYPE_MAX_VALUE (TREE_TYPE (uop)),
8380 c_common_signed_type (result_type)))
8381 /* OK */;
8382 else
8383 warning (0, "comparison between signed and unsigned");
8384 }
8385
8386 /* Warn if two unsigned values are being compared in a size
8387 larger than their original size, and one (and only one) is the
8388 result of a `~' operator. This comparison will always fail.
8389
8390 Also warn if one operand is a constant, and the constant
8391 does not have all bits set that are set in the ~ operand
8392 when it is extended. */
8393
8394 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
8395 != (TREE_CODE (primop1) == BIT_NOT_EXPR))
8396 {
8397 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
8398 primop0 = get_narrower (TREE_OPERAND (primop0, 0),
8399 &unsignedp0);
8400 else
8401 primop1 = get_narrower (TREE_OPERAND (primop1, 0),
8402 &unsignedp1);
8403
8404 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
8405 {
8406 tree primop;
8407 HOST_WIDE_INT constant, mask;
8408 int unsignedp, bits;
8409
8410 if (host_integerp (primop0, 0))
8411 {
8412 primop = primop1;
8413 unsignedp = unsignedp1;
8414 constant = tree_low_cst (primop0, 0);
8415 }
8416 else
8417 {
8418 primop = primop0;
8419 unsignedp = unsignedp0;
8420 constant = tree_low_cst (primop1, 0);
8421 }
8422
8423 bits = TYPE_PRECISION (TREE_TYPE (primop));
8424 if (bits < TYPE_PRECISION (result_type)
8425 && bits < HOST_BITS_PER_WIDE_INT && unsignedp)
8426 {
8427 mask = (~(HOST_WIDE_INT) 0) << bits;
8428 if ((mask & constant) != mask)
8429 warning (0, "comparison of promoted ~unsigned with constant");
8430 }
8431 }
8432 else if (unsignedp0 && unsignedp1
8433 && (TYPE_PRECISION (TREE_TYPE (primop0))
8434 < TYPE_PRECISION (result_type))
8435 && (TYPE_PRECISION (TREE_TYPE (primop1))
8436 < TYPE_PRECISION (result_type)))
8437 warning (0, "comparison of promoted ~unsigned with unsigned");
8438 }
8439 }
8440 }
8441 }
8442
8443 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
8444 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
8445 Then the expression will be built.
8446 It will be given type FINAL_TYPE if that is nonzero;
8447 otherwise, it will be given type RESULT_TYPE. */
8448
8449 if (!result_type)
8450 {
8451 binary_op_error (code, TREE_TYPE (op0), TREE_TYPE (op1));
8452 return error_mark_node;
8453 }
8454
8455 if (!converted)
8456 {
8457 if (TREE_TYPE (op0) != result_type)
8458 op0 = convert_and_check (result_type, op0);
8459 if (TREE_TYPE (op1) != result_type)
8460 op1 = convert_and_check (result_type, op1);
8461
8462 /* This can happen if one operand has a vector type, and the other
8463 has a different type. */
8464 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
8465 return error_mark_node;
8466 }
8467
8468 if (build_type == NULL_TREE)
8469 build_type = result_type;
8470
8471 {
8472 /* Treat expressions in initializers specially as they can't trap. */
8473 tree result = require_constant_value ? fold_build2_initializer (resultcode,
8474 build_type,
8475 op0, op1)
8476 : fold_build2 (resultcode, build_type,
8477 op0, op1);
8478
8479 if (final_type != 0)
8480 result = convert (final_type, result);
8481 return result;
8482 }
8483 }
8484
8485
8486 /* Convert EXPR to be a truth-value, validating its type for this
8487 purpose. */
8488
8489 tree
c_objc_common_truthvalue_conversion(tree expr)8490 c_objc_common_truthvalue_conversion (tree expr)
8491 {
8492 switch (TREE_CODE (TREE_TYPE (expr)))
8493 {
8494 case ARRAY_TYPE:
8495 error ("used array that cannot be converted to pointer where scalar is required");
8496 return error_mark_node;
8497
8498 case RECORD_TYPE:
8499 error ("used struct type value where scalar is required");
8500 return error_mark_node;
8501
8502 case UNION_TYPE:
8503 error ("used union type value where scalar is required");
8504 return error_mark_node;
8505
8506 case FUNCTION_TYPE:
8507 gcc_unreachable ();
8508
8509 default:
8510 break;
8511 }
8512
8513 /* ??? Should we also give an error for void and vectors rather than
8514 leaving those to give errors later? */
8515 return c_common_truthvalue_conversion (expr);
8516 }
8517
8518
8519 /* Convert EXPR to a contained DECL, updating *TC, *TI and *SE as
8520 required. */
8521
8522 tree
c_expr_to_decl(tree expr,bool * tc ATTRIBUTE_UNUSED,bool * ti ATTRIBUTE_UNUSED,bool * se)8523 c_expr_to_decl (tree expr, bool *tc ATTRIBUTE_UNUSED,
8524 bool *ti ATTRIBUTE_UNUSED, bool *se)
8525 {
8526 if (TREE_CODE (expr) == COMPOUND_LITERAL_EXPR)
8527 {
8528 tree decl = COMPOUND_LITERAL_EXPR_DECL (expr);
8529 /* Executing a compound literal inside a function reinitializes
8530 it. */
8531 if (!TREE_STATIC (decl))
8532 *se = true;
8533 return decl;
8534 }
8535 else
8536 return expr;
8537 }
8538
8539 /* Like c_begin_compound_stmt, except force the retention of the BLOCK. */
8540
8541 tree
c_begin_omp_parallel(void)8542 c_begin_omp_parallel (void)
8543 {
8544 tree block;
8545
8546 keep_next_level ();
8547 block = c_begin_compound_stmt (true);
8548
8549 return block;
8550 }
8551
8552 tree
c_finish_omp_parallel(tree clauses,tree block)8553 c_finish_omp_parallel (tree clauses, tree block)
8554 {
8555 tree stmt;
8556
8557 block = c_end_compound_stmt (block, true);
8558
8559 stmt = make_node (OMP_PARALLEL);
8560 TREE_TYPE (stmt) = void_type_node;
8561 OMP_PARALLEL_CLAUSES (stmt) = clauses;
8562 OMP_PARALLEL_BODY (stmt) = block;
8563
8564 return add_stmt (stmt);
8565 }
8566
8567 /* For all elements of CLAUSES, validate them vs OpenMP constraints.
8568 Remove any elements from the list that are invalid. */
8569
8570 tree
c_finish_omp_clauses(tree clauses)8571 c_finish_omp_clauses (tree clauses)
8572 {
8573 bitmap_head generic_head, firstprivate_head, lastprivate_head;
8574 tree c, t, *pc = &clauses;
8575 const char *name;
8576
8577 bitmap_obstack_initialize (NULL);
8578 bitmap_initialize (&generic_head, &bitmap_default_obstack);
8579 bitmap_initialize (&firstprivate_head, &bitmap_default_obstack);
8580 bitmap_initialize (&lastprivate_head, &bitmap_default_obstack);
8581
8582 for (pc = &clauses, c = clauses; c ; c = *pc)
8583 {
8584 bool remove = false;
8585 bool need_complete = false;
8586 bool need_implicitly_determined = false;
8587
8588 switch (OMP_CLAUSE_CODE (c))
8589 {
8590 case OMP_CLAUSE_SHARED:
8591 name = "shared";
8592 need_implicitly_determined = true;
8593 goto check_dup_generic;
8594
8595 case OMP_CLAUSE_PRIVATE:
8596 name = "private";
8597 need_complete = true;
8598 need_implicitly_determined = true;
8599 goto check_dup_generic;
8600
8601 case OMP_CLAUSE_REDUCTION:
8602 name = "reduction";
8603 need_implicitly_determined = true;
8604 t = OMP_CLAUSE_DECL (c);
8605 if (AGGREGATE_TYPE_P (TREE_TYPE (t))
8606 || POINTER_TYPE_P (TREE_TYPE (t)))
8607 {
8608 error ("%qE has invalid type for %<reduction%>", t);
8609 remove = true;
8610 }
8611 else if (FLOAT_TYPE_P (TREE_TYPE (t)))
8612 {
8613 enum tree_code r_code = OMP_CLAUSE_REDUCTION_CODE (c);
8614 const char *r_name = NULL;
8615
8616 switch (r_code)
8617 {
8618 case PLUS_EXPR:
8619 case MULT_EXPR:
8620 case MINUS_EXPR:
8621 break;
8622 case BIT_AND_EXPR:
8623 r_name = "&";
8624 break;
8625 case BIT_XOR_EXPR:
8626 r_name = "^";
8627 break;
8628 case BIT_IOR_EXPR:
8629 r_name = "|";
8630 break;
8631 case TRUTH_ANDIF_EXPR:
8632 r_name = "&&";
8633 break;
8634 case TRUTH_ORIF_EXPR:
8635 r_name = "||";
8636 break;
8637 default:
8638 gcc_unreachable ();
8639 }
8640 if (r_name)
8641 {
8642 error ("%qE has invalid type for %<reduction(%s)%>",
8643 t, r_name);
8644 remove = true;
8645 }
8646 }
8647 goto check_dup_generic;
8648
8649 case OMP_CLAUSE_COPYPRIVATE:
8650 name = "copyprivate";
8651 goto check_dup_generic;
8652
8653 case OMP_CLAUSE_COPYIN:
8654 name = "copyin";
8655 t = OMP_CLAUSE_DECL (c);
8656 if (TREE_CODE (t) != VAR_DECL || !DECL_THREAD_LOCAL_P (t))
8657 {
8658 error ("%qE must be %<threadprivate%> for %<copyin%>", t);
8659 remove = true;
8660 }
8661 goto check_dup_generic;
8662
8663 check_dup_generic:
8664 t = OMP_CLAUSE_DECL (c);
8665 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8666 {
8667 error ("%qE is not a variable in clause %qs", t, name);
8668 remove = true;
8669 }
8670 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8671 || bitmap_bit_p (&firstprivate_head, DECL_UID (t))
8672 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
8673 {
8674 error ("%qE appears more than once in data clauses", t);
8675 remove = true;
8676 }
8677 else
8678 bitmap_set_bit (&generic_head, DECL_UID (t));
8679 break;
8680
8681 case OMP_CLAUSE_FIRSTPRIVATE:
8682 name = "firstprivate";
8683 t = OMP_CLAUSE_DECL (c);
8684 need_complete = true;
8685 need_implicitly_determined = true;
8686 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8687 {
8688 error ("%qE is not a variable in clause %<firstprivate%>", t);
8689 remove = true;
8690 }
8691 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8692 || bitmap_bit_p (&firstprivate_head, DECL_UID (t)))
8693 {
8694 error ("%qE appears more than once in data clauses", t);
8695 remove = true;
8696 }
8697 else
8698 bitmap_set_bit (&firstprivate_head, DECL_UID (t));
8699 break;
8700
8701 case OMP_CLAUSE_LASTPRIVATE:
8702 name = "lastprivate";
8703 t = OMP_CLAUSE_DECL (c);
8704 need_complete = true;
8705 need_implicitly_determined = true;
8706 if (TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != PARM_DECL)
8707 {
8708 error ("%qE is not a variable in clause %<lastprivate%>", t);
8709 remove = true;
8710 }
8711 else if (bitmap_bit_p (&generic_head, DECL_UID (t))
8712 || bitmap_bit_p (&lastprivate_head, DECL_UID (t)))
8713 {
8714 error ("%qE appears more than once in data clauses", t);
8715 remove = true;
8716 }
8717 else
8718 bitmap_set_bit (&lastprivate_head, DECL_UID (t));
8719 break;
8720
8721 case OMP_CLAUSE_IF:
8722 case OMP_CLAUSE_NUM_THREADS:
8723 case OMP_CLAUSE_SCHEDULE:
8724 case OMP_CLAUSE_NOWAIT:
8725 case OMP_CLAUSE_ORDERED:
8726 case OMP_CLAUSE_DEFAULT:
8727 pc = &OMP_CLAUSE_CHAIN (c);
8728 continue;
8729
8730 default:
8731 gcc_unreachable ();
8732 }
8733
8734 if (!remove)
8735 {
8736 t = OMP_CLAUSE_DECL (c);
8737
8738 if (need_complete)
8739 {
8740 t = require_complete_type (t);
8741 if (t == error_mark_node)
8742 remove = true;
8743 }
8744
8745 if (need_implicitly_determined)
8746 {
8747 const char *share_name = NULL;
8748
8749 if (TREE_CODE (t) == VAR_DECL && DECL_THREAD_LOCAL_P (t))
8750 share_name = "threadprivate";
8751 else switch (c_omp_predetermined_sharing (t))
8752 {
8753 case OMP_CLAUSE_DEFAULT_UNSPECIFIED:
8754 break;
8755 case OMP_CLAUSE_DEFAULT_SHARED:
8756 share_name = "shared";
8757 break;
8758 case OMP_CLAUSE_DEFAULT_PRIVATE:
8759 share_name = "private";
8760 break;
8761 default:
8762 gcc_unreachable ();
8763 }
8764 if (share_name)
8765 {
8766 error ("%qE is predetermined %qs for %qs",
8767 t, share_name, name);
8768 remove = true;
8769 }
8770 }
8771 }
8772
8773 if (remove)
8774 *pc = OMP_CLAUSE_CHAIN (c);
8775 else
8776 pc = &OMP_CLAUSE_CHAIN (c);
8777 }
8778
8779 bitmap_obstack_release (NULL);
8780 return clauses;
8781 }
8782