1/* Build expressions with type checking for C++ compiler.
2 Copyright (C) 1987-2017 Free Software Foundation, Inc.
3 Hacked by Michael Tiemann (tiemann@cygnus.com)
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify
8it under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 3, or (at your option)
10any later version.
11
12GCC is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING3. If not see
19<http://www.gnu.org/licenses/>. */
20
21
22/* This file is part of the C++ front end.
23 It contains routines to build C++ expressions given their operands,
24 including computing the types of the result, C and C++ specific error
25 checks, and some optimization. */
26
27#include "config.h"
28#include "system.h"
29#include "coretypes.h"
30#include "target.h"
31#include "cp-tree.h"
32#include "stor-layout.h"
33#include "varasm.h"
34#include "intl.h"
35#include "convert.h"
36#include "c-family/c-objc.h"
37#include "c-family/c-ubsan.h"
38#include "params.h"
39#include "gcc-rich-location.h"
40#include "stringpool.h"
41#include "attribs.h"
42#include "asan.h"
43
44static tree cp_build_addr_expr_strict (tree, tsubst_flags_t);
45static tree cp_build_function_call (tree, tree, tsubst_flags_t);
46static tree pfn_from_ptrmemfunc (tree);
47static tree delta_from_ptrmemfunc (tree);
48static tree convert_for_assignment (tree, tree, impl_conv_rhs, tree, int,
49 tsubst_flags_t, int);
50static tree cp_pointer_int_sum (location_t, enum tree_code, tree, tree,
51 tsubst_flags_t);
52static tree rationalize_conditional_expr (enum tree_code, tree,
53 tsubst_flags_t);
54static int comp_ptr_ttypes_real (tree, tree, int);
55static bool comp_except_types (tree, tree, bool);
56static bool comp_array_types (const_tree, const_tree, bool);
57static tree pointer_diff (location_t, tree, tree, tree, tsubst_flags_t, tree *);
58static tree get_delta_difference (tree, tree, bool, bool, tsubst_flags_t);
59static void casts_away_constness_r (tree *, tree *, tsubst_flags_t);
60static bool casts_away_constness (tree, tree, tsubst_flags_t);
61static bool maybe_warn_about_returning_address_of_local (tree);
62static tree lookup_destructor (tree, tree, tree, tsubst_flags_t);
63static void error_args_num (location_t, tree, bool);
64static int convert_arguments (tree, vec<tree, va_gc> **, tree, int,
65 tsubst_flags_t);
66
67/* Do `exp = require_complete_type (exp);' to make sure exp
68 does not have an incomplete type. (That includes void types.)
69 Returns error_mark_node if the VALUE does not have
70 complete type when this function returns. */
71
72tree
73require_complete_type_sfinae (tree value, tsubst_flags_t complain)
74{
75 tree type;
76
77 if (processing_template_decl || value == error_mark_node)
78 return value;
79
80 if (TREE_CODE (value) == OVERLOAD)
81 type = unknown_type_node;
82 else
83 type = TREE_TYPE (value);
84
85 if (type == error_mark_node)
86 return error_mark_node;
87
88 /* First, detect a valid value with a complete type. */
89 if (COMPLETE_TYPE_P (type))
90 return value;
91
92 if (complete_type_or_maybe_complain (type, value, complain))
93 return value;
94 else
95 return error_mark_node;
96}
97
98tree
99require_complete_type (tree value)
100{
101 return require_complete_type_sfinae (value, tf_warning_or_error);
102}
103
104/* Try to complete TYPE, if it is incomplete. For example, if TYPE is
105 a template instantiation, do the instantiation. Returns TYPE,
106 whether or not it could be completed, unless something goes
107 horribly wrong, in which case the error_mark_node is returned. */
108
109tree
110complete_type (tree type)
111{
112 if (type == NULL_TREE)
113 /* Rather than crash, we return something sure to cause an error
114 at some point. */
115 return error_mark_node;
116
117 if (type == error_mark_node || COMPLETE_TYPE_P (type))
118 ;
119 else if (TREE_CODE (type) == ARRAY_TYPE)
120 {
121 tree t = complete_type (TREE_TYPE (type));
122 unsigned int needs_constructing, has_nontrivial_dtor;
123 if (COMPLETE_TYPE_P (t) && !dependent_type_p (type))
124 layout_type (type);
125 needs_constructing
126 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
127 has_nontrivial_dtor
128 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
129 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
130 {
131 TYPE_NEEDS_CONSTRUCTING (t) = needs_constructing;
132 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = has_nontrivial_dtor;
133 }
134 }
135 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
136 instantiate_class_template (TYPE_MAIN_VARIANT (type));
137
138 return type;
139}
140
141/* Like complete_type, but issue an error if the TYPE cannot be completed.
142 VALUE is used for informative diagnostics.
143 Returns NULL_TREE if the type cannot be made complete. */
144
145tree
146complete_type_or_maybe_complain (tree type, tree value, tsubst_flags_t complain)
147{
148 type = complete_type (type);
149 if (type == error_mark_node)
150 /* We already issued an error. */
151 return NULL_TREE;
152 else if (!COMPLETE_TYPE_P (type))
153 {
154 if (complain & tf_error)
155 cxx_incomplete_type_diagnostic (value, type, DK_ERROR);
156 return NULL_TREE;
157 }
158 else
159 return type;
160}
161
162tree
163complete_type_or_else (tree type, tree value)
164{
165 return complete_type_or_maybe_complain (type, value, tf_warning_or_error);
166}
167
168
169/* Return the common type of two parameter lists.
170 We assume that comptypes has already been done and returned 1;
171 if that isn't so, this may crash.
172
173 As an optimization, free the space we allocate if the parameter
174 lists are already common. */
175
176static tree
177commonparms (tree p1, tree p2)
178{
179 tree oldargs = p1, newargs, n;
180 int i, len;
181 int any_change = 0;
182
183 len = list_length (p1);
184 newargs = tree_last (p1);
185
186 if (newargs == void_list_node)
187 i = 1;
188 else
189 {
190 i = 0;
191 newargs = 0;
192 }
193
194 for (; i < len; i++)
195 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
196
197 n = newargs;
198
199 for (i = 0; p1;
200 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
201 {
202 if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
203 {
204 TREE_PURPOSE (n) = TREE_PURPOSE (p1);
205 any_change = 1;
206 }
207 else if (! TREE_PURPOSE (p1))
208 {
209 if (TREE_PURPOSE (p2))
210 {
211 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
212 any_change = 1;
213 }
214 }
215 else
216 {
217 if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
218 any_change = 1;
219 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
220 }
221 if (TREE_VALUE (p1) != TREE_VALUE (p2))
222 {
223 any_change = 1;
224 TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2));
225 }
226 else
227 TREE_VALUE (n) = TREE_VALUE (p1);
228 }
229 if (! any_change)
230 return oldargs;
231
232 return newargs;
233}
234
235/* Given a type, perhaps copied for a typedef,
236 find the "original" version of it. */
237static tree
238original_type (tree t)
239{
240 int quals = cp_type_quals (t);
241 while (t != error_mark_node
242 && TYPE_NAME (t) != NULL_TREE)
243 {
244 tree x = TYPE_NAME (t);
245 if (TREE_CODE (x) != TYPE_DECL)
246 break;
247 x = DECL_ORIGINAL_TYPE (x);
248 if (x == NULL_TREE)
249 break;
250 t = x;
251 }
252 return cp_build_qualified_type (t, quals);
253}
254
255/* Return the common type for two arithmetic types T1 and T2 under the
256 usual arithmetic conversions. The default conversions have already
257 been applied, and enumerated types converted to their compatible
258 integer types. */
259
260static tree
261cp_common_type (tree t1, tree t2)
262{
263 enum tree_code code1 = TREE_CODE (t1);
264 enum tree_code code2 = TREE_CODE (t2);
265 tree attributes;
266 int i;
267
268
269 /* In what follows, we slightly generalize the rules given in [expr] so
270 as to deal with `long long' and `complex'. First, merge the
271 attributes. */
272 attributes = (*targetm.merge_type_attributes) (t1, t2);
273
274 if (SCOPED_ENUM_P (t1) || SCOPED_ENUM_P (t2))
275 {
276 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
277 return build_type_attribute_variant (t1, attributes);
278 else
279 return NULL_TREE;
280 }
281
282 /* FIXME: Attributes. */
283 gcc_assert (ARITHMETIC_TYPE_P (t1)
284 || VECTOR_TYPE_P (t1)
285 || UNSCOPED_ENUM_P (t1));
286 gcc_assert (ARITHMETIC_TYPE_P (t2)
287 || VECTOR_TYPE_P (t2)
288 || UNSCOPED_ENUM_P (t2));
289
290 /* If one type is complex, form the common type of the non-complex
291 components, then make that complex. Use T1 or T2 if it is the
292 required type. */
293 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
294 {
295 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
296 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
297 tree subtype
298 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
299
300 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
301 return build_type_attribute_variant (t1, attributes);
302 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
303 return build_type_attribute_variant (t2, attributes);
304 else
305 return build_type_attribute_variant (build_complex_type (subtype),
306 attributes);
307 }
308
309 if (code1 == VECTOR_TYPE)
310 {
311 /* When we get here we should have two vectors of the same size.
312 Just prefer the unsigned one if present. */
313 if (TYPE_UNSIGNED (t1))
314 return build_type_attribute_variant (t1, attributes);
315 else
316 return build_type_attribute_variant (t2, attributes);
317 }
318
319 /* If only one is real, use it as the result. */
320 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
321 return build_type_attribute_variant (t1, attributes);
322 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
323 return build_type_attribute_variant (t2, attributes);
324
325 /* Both real or both integers; use the one with greater precision. */
326 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
327 return build_type_attribute_variant (t1, attributes);
328 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
329 return build_type_attribute_variant (t2, attributes);
330
331 /* The types are the same; no need to do anything fancy. */
332 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
333 return build_type_attribute_variant (t1, attributes);
334
335 if (code1 != REAL_TYPE)
336 {
337 /* If one is unsigned long long, then convert the other to unsigned
338 long long. */
339 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
340 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
341 return build_type_attribute_variant (long_long_unsigned_type_node,
342 attributes);
343 /* If one is a long long, and the other is an unsigned long, and
344 long long can represent all the values of an unsigned long, then
345 convert to a long long. Otherwise, convert to an unsigned long
346 long. Otherwise, if either operand is long long, convert the
347 other to long long.
348
349 Since we're here, we know the TYPE_PRECISION is the same;
350 therefore converting to long long cannot represent all the values
351 of an unsigned long, so we choose unsigned long long in that
352 case. */
353 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
354 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
355 {
356 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
357 ? long_long_unsigned_type_node
358 : long_long_integer_type_node);
359 return build_type_attribute_variant (t, attributes);
360 }
361
362 /* Go through the same procedure, but for longs. */
363 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
364 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
365 return build_type_attribute_variant (long_unsigned_type_node,
366 attributes);
367 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
368 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
369 {
370 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
371 ? long_unsigned_type_node : long_integer_type_node);
372 return build_type_attribute_variant (t, attributes);
373 }
374
375 /* For __intN types, either the type is __int128 (and is lower
376 priority than the types checked above, but higher than other
377 128-bit types) or it's known to not be the same size as other
378 types (enforced in toplev.c). Prefer the unsigned type. */
379 for (i = 0; i < NUM_INT_N_ENTS; i ++)
380 {
381 if (int_n_enabled_p [i]
382 && (same_type_p (TYPE_MAIN_VARIANT (t1), int_n_trees[i].signed_type)
383 || same_type_p (TYPE_MAIN_VARIANT (t2), int_n_trees[i].signed_type)
384 || same_type_p (TYPE_MAIN_VARIANT (t1), int_n_trees[i].unsigned_type)
385 || same_type_p (TYPE_MAIN_VARIANT (t2), int_n_trees[i].unsigned_type)))
386 {
387 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
388 ? int_n_trees[i].unsigned_type
389 : int_n_trees[i].signed_type);
390 return build_type_attribute_variant (t, attributes);
391 }
392 }
393
394 /* Otherwise prefer the unsigned one. */
395 if (TYPE_UNSIGNED (t1))
396 return build_type_attribute_variant (t1, attributes);
397 else
398 return build_type_attribute_variant (t2, attributes);
399 }
400 else
401 {
402 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
403 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
404 return build_type_attribute_variant (long_double_type_node,
405 attributes);
406 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
407 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
408 return build_type_attribute_variant (double_type_node,
409 attributes);
410 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
411 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
412 return build_type_attribute_variant (float_type_node,
413 attributes);
414
415 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
416 the standard C++ floating-point types. Logic earlier in this
417 function has already eliminated the possibility that
418 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
419 compelling reason to choose one or the other. */
420 return build_type_attribute_variant (t1, attributes);
421 }
422}
423
424/* T1 and T2 are arithmetic or enumeration types. Return the type
425 that will result from the "usual arithmetic conversions" on T1 and
426 T2 as described in [expr]. */
427
428tree
429type_after_usual_arithmetic_conversions (tree t1, tree t2)
430{
431 gcc_assert (ARITHMETIC_TYPE_P (t1)
432 || VECTOR_TYPE_P (t1)
433 || UNSCOPED_ENUM_P (t1));
434 gcc_assert (ARITHMETIC_TYPE_P (t2)
435 || VECTOR_TYPE_P (t2)
436 || UNSCOPED_ENUM_P (t2));
437
438 /* Perform the integral promotions. We do not promote real types here. */
439 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t1)
440 && INTEGRAL_OR_ENUMERATION_TYPE_P (t2))
441 {
442 t1 = type_promotes_to (t1);
443 t2 = type_promotes_to (t2);
444 }
445
446 return cp_common_type (t1, t2);
447}
448
449static void
450composite_pointer_error (diagnostic_t kind, tree t1, tree t2,
451 composite_pointer_operation operation)
452{
453 switch (operation)
454 {
455 case CPO_COMPARISON:
456 emit_diagnostic (kind, input_location, 0,
457 "comparison between "
458 "distinct pointer types %qT and %qT lacks a cast",
459 t1, t2);
460 break;
461 case CPO_CONVERSION:
462 emit_diagnostic (kind, input_location, 0,
463 "conversion between "
464 "distinct pointer types %qT and %qT lacks a cast",
465 t1, t2);
466 break;
467 case CPO_CONDITIONAL_EXPR:
468 emit_diagnostic (kind, input_location, 0,
469 "conditional expression between "
470 "distinct pointer types %qT and %qT lacks a cast",
471 t1, t2);
472 break;
473 default:
474 gcc_unreachable ();
475 }
476}
477
478/* Subroutine of composite_pointer_type to implement the recursive
479 case. See that function for documentation of the parameters. */
480
481static tree
482composite_pointer_type_r (tree t1, tree t2,
483 composite_pointer_operation operation,
484 tsubst_flags_t complain)
485{
486 tree pointee1;
487 tree pointee2;
488 tree result_type;
489 tree attributes;
490
491 /* Determine the types pointed to by T1 and T2. */
492 if (TYPE_PTR_P (t1))
493 {
494 pointee1 = TREE_TYPE (t1);
495 pointee2 = TREE_TYPE (t2);
496 }
497 else
498 {
499 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
500 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
501 }
502
503 /* [expr.rel]
504
505 Otherwise, the composite pointer type is a pointer type
506 similar (_conv.qual_) to the type of one of the operands,
507 with a cv-qualification signature (_conv.qual_) that is the
508 union of the cv-qualification signatures of the operand
509 types. */
510 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
511 result_type = pointee1;
512 else if ((TYPE_PTR_P (pointee1) && TYPE_PTR_P (pointee2))
513 || (TYPE_PTRMEM_P (pointee1) && TYPE_PTRMEM_P (pointee2)))
514 {
515 result_type = composite_pointer_type_r (pointee1, pointee2, operation,
516 complain);
517 if (result_type == error_mark_node)
518 return error_mark_node;
519 }
520 else
521 {
522 if (complain & tf_error)
523 composite_pointer_error (DK_PERMERROR, t1, t2, operation);
524 else
525 return error_mark_node;
526 result_type = void_type_node;
527 }
528 result_type = cp_build_qualified_type (result_type,
529 (cp_type_quals (pointee1)
530 | cp_type_quals (pointee2)));
531 /* If the original types were pointers to members, so is the
532 result. */
533 if (TYPE_PTRMEM_P (t1))
534 {
535 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
536 TYPE_PTRMEM_CLASS_TYPE (t2)))
537 {
538 if (complain & tf_error)
539 composite_pointer_error (DK_PERMERROR, t1, t2, operation);
540 else
541 return error_mark_node;
542 }
543 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
544 result_type);
545 }
546 else
547 result_type = build_pointer_type (result_type);
548
549 /* Merge the attributes. */
550 attributes = (*targetm.merge_type_attributes) (t1, t2);
551 return build_type_attribute_variant (result_type, attributes);
552}
553
554/* Return the composite pointer type (see [expr.rel]) for T1 and T2.
555 ARG1 and ARG2 are the values with those types. The OPERATION is to
556 describe the operation between the pointer types,
557 in case an error occurs.
558
559 This routine also implements the computation of a common type for
560 pointers-to-members as per [expr.eq]. */
561
562tree
563composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
564 composite_pointer_operation operation,
565 tsubst_flags_t complain)
566{
567 tree class1;
568 tree class2;
569
570 /* [expr.rel]
571
572 If one operand is a null pointer constant, the composite pointer
573 type is the type of the other operand. */
574 if (null_ptr_cst_p (arg1))
575 return t2;
576 if (null_ptr_cst_p (arg2))
577 return t1;
578
579 /* We have:
580
581 [expr.rel]
582
583 If one of the operands has type "pointer to cv1 void*", then
584 the other has type "pointer to cv2T", and the composite pointer
585 type is "pointer to cv12 void", where cv12 is the union of cv1
586 and cv2.
587
588 If either type is a pointer to void, make sure it is T1. */
589 if (TYPE_PTR_P (t2) && VOID_TYPE_P (TREE_TYPE (t2)))
590 std::swap (t1, t2);
591
592 /* Now, if T1 is a pointer to void, merge the qualifiers. */
593 if (TYPE_PTR_P (t1) && VOID_TYPE_P (TREE_TYPE (t1)))
594 {
595 tree attributes;
596 tree result_type;
597
598 if (TYPE_PTRFN_P (t2))
599 {
600 if (complain & tf_error)
601 {
602 switch (operation)
603 {
604 case CPO_COMPARISON:
605 pedwarn (input_location, OPT_Wpedantic,
606 "ISO C++ forbids comparison between pointer "
607 "of type %<void *%> and pointer-to-function");
608 break;
609 case CPO_CONVERSION:
610 pedwarn (input_location, OPT_Wpedantic,
611 "ISO C++ forbids conversion between pointer "
612 "of type %<void *%> and pointer-to-function");
613 break;
614 case CPO_CONDITIONAL_EXPR:
615 pedwarn (input_location, OPT_Wpedantic,
616 "ISO C++ forbids conditional expression between "
617 "pointer of type %<void *%> and "
618 "pointer-to-function");
619 break;
620 default:
621 gcc_unreachable ();
622 }
623 }
624 else
625 return error_mark_node;
626 }
627 result_type
628 = cp_build_qualified_type (void_type_node,
629 (cp_type_quals (TREE_TYPE (t1))
630 | cp_type_quals (TREE_TYPE (t2))));
631 result_type = build_pointer_type (result_type);
632 /* Merge the attributes. */
633 attributes = (*targetm.merge_type_attributes) (t1, t2);
634 return build_type_attribute_variant (result_type, attributes);
635 }
636
637 if (c_dialect_objc () && TYPE_PTR_P (t1)
638 && TYPE_PTR_P (t2))
639 {
640 if (objc_have_common_type (t1, t2, -3, NULL_TREE))
641 return objc_common_type (t1, t2);
642 }
643
644 /* if T1 or T2 is "pointer to noexcept function" and the other type is
645 "pointer to function", where the function types are otherwise the same,
646 "pointer to function" */
647 if (fnptr_conv_p (t1, t2))
648 return t1;
649 if (fnptr_conv_p (t2, t1))
650 return t2;
651
652 /* [expr.eq] permits the application of a pointer conversion to
653 bring the pointers to a common type. */
654 if (TYPE_PTR_P (t1) && TYPE_PTR_P (t2)
655 && CLASS_TYPE_P (TREE_TYPE (t1))
656 && CLASS_TYPE_P (TREE_TYPE (t2))
657 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
658 TREE_TYPE (t2)))
659 {
660 class1 = TREE_TYPE (t1);
661 class2 = TREE_TYPE (t2);
662
663 if (DERIVED_FROM_P (class1, class2))
664 t2 = (build_pointer_type
665 (cp_build_qualified_type (class1, cp_type_quals (class2))));
666 else if (DERIVED_FROM_P (class2, class1))
667 t1 = (build_pointer_type
668 (cp_build_qualified_type (class2, cp_type_quals (class1))));
669 else
670 {
671 if (complain & tf_error)
672 composite_pointer_error (DK_ERROR, t1, t2, operation);
673 return error_mark_node;
674 }
675 }
676 /* [expr.eq] permits the application of a pointer-to-member
677 conversion to change the class type of one of the types. */
678 else if (TYPE_PTRMEM_P (t1)
679 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
680 TYPE_PTRMEM_CLASS_TYPE (t2)))
681 {
682 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
683 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
684
685 if (DERIVED_FROM_P (class1, class2))
686 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
687 else if (DERIVED_FROM_P (class2, class1))
688 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
689 else
690 {
691 if (complain & tf_error)
692 switch (operation)
693 {
694 case CPO_COMPARISON:
695 error ("comparison between distinct "
696 "pointer-to-member types %qT and %qT lacks a cast",
697 t1, t2);
698 break;
699 case CPO_CONVERSION:
700 error ("conversion between distinct "
701 "pointer-to-member types %qT and %qT lacks a cast",
702 t1, t2);
703 break;
704 case CPO_CONDITIONAL_EXPR:
705 error ("conditional expression between distinct "
706 "pointer-to-member types %qT and %qT lacks a cast",
707 t1, t2);
708 break;
709 default:
710 gcc_unreachable ();
711 }
712 return error_mark_node;
713 }
714 }
715
716 return composite_pointer_type_r (t1, t2, operation, complain);
717}
718
719/* Return the merged type of two types.
720 We assume that comptypes has already been done and returned 1;
721 if that isn't so, this may crash.
722
723 This just combines attributes and default arguments; any other
724 differences would cause the two types to compare unalike. */
725
726tree
727merge_types (tree t1, tree t2)
728{
729 enum tree_code code1;
730 enum tree_code code2;
731 tree attributes;
732
733 /* Save time if the two types are the same. */
734 if (t1 == t2)
735 return t1;
736 if (original_type (t1) == original_type (t2))
737 return t1;
738
739 /* If one type is nonsense, use the other. */
740 if (t1 == error_mark_node)
741 return t2;
742 if (t2 == error_mark_node)
743 return t1;
744
745 /* Handle merging an auto redeclaration with a previous deduced
746 return type. */
747 if (is_auto (t1))
748 return t2;
749
750 /* Merge the attributes. */
751 attributes = (*targetm.merge_type_attributes) (t1, t2);
752
753 if (TYPE_PTRMEMFUNC_P (t1))
754 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
755 if (TYPE_PTRMEMFUNC_P (t2))
756 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
757
758 code1 = TREE_CODE (t1);
759 code2 = TREE_CODE (t2);
760 if (code1 != code2)
761 {
762 gcc_assert (code1 == TYPENAME_TYPE || code2 == TYPENAME_TYPE);
763 if (code1 == TYPENAME_TYPE)
764 {
765 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
766 code1 = TREE_CODE (t1);
767 }
768 else
769 {
770 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
771 code2 = TREE_CODE (t2);
772 }
773 }
774
775 switch (code1)
776 {
777 case POINTER_TYPE:
778 case REFERENCE_TYPE:
779 /* For two pointers, do this recursively on the target type. */
780 {
781 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
782 int quals = cp_type_quals (t1);
783
784 if (code1 == POINTER_TYPE)
785 {
786 t1 = build_pointer_type (target);
787 if (TREE_CODE (target) == METHOD_TYPE)
788 t1 = build_ptrmemfunc_type (t1);
789 }
790 else
791 t1 = cp_build_reference_type (target, TYPE_REF_IS_RVALUE (t1));
792 t1 = build_type_attribute_variant (t1, attributes);
793 t1 = cp_build_qualified_type (t1, quals);
794
795 return t1;
796 }
797
798 case OFFSET_TYPE:
799 {
800 int quals;
801 tree pointee;
802 quals = cp_type_quals (t1);
803 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
804 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
805 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
806 pointee);
807 t1 = cp_build_qualified_type (t1, quals);
808 break;
809 }
810
811 case ARRAY_TYPE:
812 {
813 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
814 /* Save space: see if the result is identical to one of the args. */
815 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
816 return build_type_attribute_variant (t1, attributes);
817 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
818 return build_type_attribute_variant (t2, attributes);
819 /* Merge the element types, and have a size if either arg has one. */
820 t1 = build_cplus_array_type
821 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
822 break;
823 }
824
825 case FUNCTION_TYPE:
826 /* Function types: prefer the one that specified arg types.
827 If both do, merge the arg types. Also merge the return types. */
828 {
829 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
830 tree p1 = TYPE_ARG_TYPES (t1);
831 tree p2 = TYPE_ARG_TYPES (t2);
832 tree parms;
833 tree rval, raises;
834 bool late_return_type_p = TYPE_HAS_LATE_RETURN_TYPE (t1);
835
836 /* Save space: see if the result is identical to one of the args. */
837 if (valtype == TREE_TYPE (t1) && ! p2)
838 return cp_build_type_attribute_variant (t1, attributes);
839 if (valtype == TREE_TYPE (t2) && ! p1)
840 return cp_build_type_attribute_variant (t2, attributes);
841
842 /* Simple way if one arg fails to specify argument types. */
843 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
844 parms = p2;
845 else if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
846 parms = p1;
847 else
848 parms = commonparms (p1, p2);
849
850 rval = build_function_type (valtype, parms);
851 gcc_assert (type_memfn_quals (t1) == type_memfn_quals (t2));
852 gcc_assert (type_memfn_rqual (t1) == type_memfn_rqual (t2));
853 rval = apply_memfn_quals (rval,
854 type_memfn_quals (t1),
855 type_memfn_rqual (t1));
856 raises = merge_exception_specifiers (TYPE_RAISES_EXCEPTIONS (t1),
857 TYPE_RAISES_EXCEPTIONS (t2));
858 t1 = build_exception_variant (rval, raises);
859 if (late_return_type_p)
860 TYPE_HAS_LATE_RETURN_TYPE (t1) = 1;
861 break;
862 }
863
864 case METHOD_TYPE:
865 {
866 /* Get this value the long way, since TYPE_METHOD_BASETYPE
867 is just the main variant of this. */
868 tree basetype = class_of_this_parm (t2);
869 tree raises = merge_exception_specifiers (TYPE_RAISES_EXCEPTIONS (t1),
870 TYPE_RAISES_EXCEPTIONS (t2));
871 cp_ref_qualifier rqual = type_memfn_rqual (t1);
872 tree t3;
873 bool late_return_type_1_p = TYPE_HAS_LATE_RETURN_TYPE (t1);
874 bool late_return_type_2_p = TYPE_HAS_LATE_RETURN_TYPE (t2);
875
876 /* If this was a member function type, get back to the
877 original type of type member function (i.e., without
878 the class instance variable up front. */
879 t1 = build_function_type (TREE_TYPE (t1),
880 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
881 t2 = build_function_type (TREE_TYPE (t2),
882 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
883 t3 = merge_types (t1, t2);
884 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
885 TYPE_ARG_TYPES (t3));
886 t1 = build_exception_variant (t3, raises);
887 t1 = build_ref_qualified_type (t1, rqual);
888 if (late_return_type_1_p)
889 TYPE_HAS_LATE_RETURN_TYPE (t1) = 1;
890 if (late_return_type_2_p)
891 TYPE_HAS_LATE_RETURN_TYPE (t2) = 1;
892 break;
893 }
894
895 case TYPENAME_TYPE:
896 /* There is no need to merge attributes into a TYPENAME_TYPE.
897 When the type is instantiated it will have whatever
898 attributes result from the instantiation. */
899 return t1;
900
901 default:;
902 }
903
904 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
905 return t1;
906 else if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
907 return t2;
908 else
909 return cp_build_type_attribute_variant (t1, attributes);
910}
911
912/* Return the ARRAY_TYPE type without its domain. */
913
914tree
915strip_array_domain (tree type)
916{
917 tree t2;
918 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
919 if (TYPE_DOMAIN (type) == NULL_TREE)
920 return type;
921 t2 = build_cplus_array_type (TREE_TYPE (type), NULL_TREE);
922 return cp_build_type_attribute_variant (t2, TYPE_ATTRIBUTES (type));
923}
924
925/* Wrapper around cp_common_type that is used by c-common.c and other
926 front end optimizations that remove promotions.
927
928 Return the common type for two arithmetic types T1 and T2 under the
929 usual arithmetic conversions. The default conversions have already
930 been applied, and enumerated types converted to their compatible
931 integer types. */
932
933tree
934common_type (tree t1, tree t2)
935{
936 /* If one type is nonsense, use the other */
937 if (t1 == error_mark_node)
938 return t2;
939 if (t2 == error_mark_node)
940 return t1;
941
942 return cp_common_type (t1, t2);
943}
944
945/* Return the common type of two pointer types T1 and T2. This is the
946 type for the result of most arithmetic operations if the operands
947 have the given two types.
948
949 We assume that comp_target_types has already been done and returned
950 nonzero; if that isn't so, this may crash. */
951
952tree
953common_pointer_type (tree t1, tree t2)
954{
955 gcc_assert ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
956 || (TYPE_PTRDATAMEM_P (t1) && TYPE_PTRDATAMEM_P (t2))
957 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)));
958
959 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
960 CPO_CONVERSION, tf_warning_or_error);
961}
962
963/* Compare two exception specifier types for exactness or subsetness, if
964 allowed. Returns false for mismatch, true for match (same, or
965 derived and !exact).
966
967 [except.spec] "If a class X ... objects of class X or any class publicly
968 and unambiguously derived from X. Similarly, if a pointer type Y * ...
969 exceptions of type Y * or that are pointers to any type publicly and
970 unambiguously derived from Y. Otherwise a function only allows exceptions
971 that have the same type ..."
972 This does not mention cv qualifiers and is different to what throw
973 [except.throw] and catch [except.catch] will do. They will ignore the
974 top level cv qualifiers, and allow qualifiers in the pointer to class
975 example.
976
977 We implement the letter of the standard. */
978
979static bool
980comp_except_types (tree a, tree b, bool exact)
981{
982 if (same_type_p (a, b))
983 return true;
984 else if (!exact)
985 {
986 if (cp_type_quals (a) || cp_type_quals (b))
987 return false;
988
989 if (TYPE_PTR_P (a) && TYPE_PTR_P (b))
990 {
991 a = TREE_TYPE (a);
992 b = TREE_TYPE (b);
993 if (cp_type_quals (a) || cp_type_quals (b))
994 return false;
995 }
996
997 if (TREE_CODE (a) != RECORD_TYPE
998 || TREE_CODE (b) != RECORD_TYPE)
999 return false;
1000
1001 if (publicly_uniquely_derived_p (a, b))
1002 return true;
1003 }
1004 return false;
1005}
1006
1007/* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
1008 If EXACT is ce_derived, T2 can be stricter than T1 (according to 15.4/5).
1009 If EXACT is ce_type, the C++17 type compatibility rules apply.
1010 If EXACT is ce_normal, the compatibility rules in 15.4/3 apply.
1011 If EXACT is ce_exact, the specs must be exactly the same. Exception lists
1012 are unordered, but we've already filtered out duplicates. Most lists will
1013 be in order, we should try to make use of that. */
1014
1015bool
1016comp_except_specs (const_tree t1, const_tree t2, int exact)
1017{
1018 const_tree probe;
1019 const_tree base;
1020 int length = 0;
1021
1022 if (t1 == t2)
1023 return true;
1024
1025 /* First handle noexcept. */
1026 if (exact < ce_exact)
1027 {
1028 if (exact == ce_type
1029 && (canonical_eh_spec (CONST_CAST_TREE (t1))
1030 == canonical_eh_spec (CONST_CAST_TREE (t2))))
1031 return true;
1032
1033 /* noexcept(false) is compatible with no exception-specification,
1034 and less strict than any spec. */
1035 if (t1 == noexcept_false_spec)
1036 return t2 == NULL_TREE || exact == ce_derived;
1037 /* Even a derived noexcept(false) is compatible with no
1038 exception-specification. */
1039 if (t2 == noexcept_false_spec)
1040 return t1 == NULL_TREE;
1041
1042 /* Otherwise, if we aren't looking for an exact match, noexcept is
1043 equivalent to throw(). */
1044 if (t1 == noexcept_true_spec)
1045 t1 = empty_except_spec;
1046 if (t2 == noexcept_true_spec)
1047 t2 = empty_except_spec;
1048 }
1049
1050 /* If any noexcept is left, it is only comparable to itself;
1051 either we're looking for an exact match or we're redeclaring a
1052 template with dependent noexcept. */
1053 if ((t1 && TREE_PURPOSE (t1))
1054 || (t2 && TREE_PURPOSE (t2)))
1055 return (t1 && t2
1056 && cp_tree_equal (TREE_PURPOSE (t1), TREE_PURPOSE (t2)));
1057
1058 if (t1 == NULL_TREE) /* T1 is ... */
1059 return t2 == NULL_TREE || exact == ce_derived;
1060 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
1061 return t2 != NULL_TREE && !TREE_VALUE (t2);
1062 if (t2 == NULL_TREE) /* T2 is ... */
1063 return false;
1064 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
1065 return exact == ce_derived;
1066
1067 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
1068 Count how many we find, to determine exactness. For exact matching and
1069 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
1070 O(nm). */
1071 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
1072 {
1073 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
1074 {
1075 tree a = TREE_VALUE (probe);
1076 tree b = TREE_VALUE (t2);
1077
1078 if (comp_except_types (a, b, exact))
1079 {
1080 if (probe == base && exact > ce_derived)
1081 base = TREE_CHAIN (probe);
1082 length++;
1083 break;
1084 }
1085 }
1086 if (probe == NULL_TREE)
1087 return false;
1088 }
1089 return exact == ce_derived || base == NULL_TREE || length == list_length (t1);
1090}
1091
1092/* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
1093 [] can match [size]. */
1094
1095static bool
1096comp_array_types (const_tree t1, const_tree t2, bool allow_redeclaration)
1097{
1098 tree d1;
1099 tree d2;
1100 tree max1, max2;
1101
1102 if (t1 == t2)
1103 return true;
1104
1105 /* The type of the array elements must be the same. */
1106 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1107 return false;
1108
1109 d1 = TYPE_DOMAIN (t1);
1110 d2 = TYPE_DOMAIN (t2);
1111
1112 if (d1 == d2)
1113 return true;
1114
1115 /* If one of the arrays is dimensionless, and the other has a
1116 dimension, they are of different types. However, it is valid to
1117 write:
1118
1119 extern int a[];
1120 int a[3];
1121
1122 by [basic.link]:
1123
1124 declarations for an array object can specify
1125 array types that differ by the presence or absence of a major
1126 array bound (_dcl.array_). */
1127 if (!d1 || !d2)
1128 return allow_redeclaration;
1129
1130 /* Check that the dimensions are the same. */
1131
1132 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
1133 return false;
1134 max1 = TYPE_MAX_VALUE (d1);
1135 max2 = TYPE_MAX_VALUE (d2);
1136
1137 if (!cp_tree_equal (max1, max2))
1138 return false;
1139
1140 return true;
1141}
1142
1143/* Compare the relative position of T1 and T2 into their respective
1144 template parameter list.
1145 T1 and T2 must be template parameter types.
1146 Return TRUE if T1 and T2 have the same position, FALSE otherwise. */
1147
1148static bool
1149comp_template_parms_position (tree t1, tree t2)
1150{
1151 tree index1, index2;
1152 gcc_assert (t1 && t2
1153 && TREE_CODE (t1) == TREE_CODE (t2)
1154 && (TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM
1155 || TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM
1156 || TREE_CODE (t1) == TEMPLATE_TYPE_PARM));
1157
1158 index1 = TEMPLATE_TYPE_PARM_INDEX (TYPE_MAIN_VARIANT (t1));
1159 index2 = TEMPLATE_TYPE_PARM_INDEX (TYPE_MAIN_VARIANT (t2));
1160
1161 /* Then compare their relative position. */
1162 if (TEMPLATE_PARM_IDX (index1) != TEMPLATE_PARM_IDX (index2)
1163 || TEMPLATE_PARM_LEVEL (index1) != TEMPLATE_PARM_LEVEL (index2)
1164 || (TEMPLATE_PARM_PARAMETER_PACK (index1)
1165 != TEMPLATE_PARM_PARAMETER_PACK (index2)))
1166 return false;
1167
1168 /* In C++14 we can end up comparing 'auto' to a normal template
1169 parameter. Don't confuse them. */
1170 if (cxx_dialect >= cxx14 && (is_auto (t1) || is_auto (t2)))
1171 return TYPE_IDENTIFIER (t1) == TYPE_IDENTIFIER (t2);
1172
1173 return true;
1174}
1175
1176/* Subroutine in comptypes. */
1177
1178static bool
1179structural_comptypes (tree t1, tree t2, int strict)
1180{
1181 if (t1 == t2)
1182 return true;
1183
1184 /* Suppress errors caused by previously reported errors. */
1185 if (t1 == error_mark_node || t2 == error_mark_node)
1186 return false;
1187
1188 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
1189
1190 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
1191 current instantiation. */
1192 if (TREE_CODE (t1) == TYPENAME_TYPE)
1193 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
1194
1195 if (TREE_CODE (t2) == TYPENAME_TYPE)
1196 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
1197
1198 if (TYPE_PTRMEMFUNC_P (t1))
1199 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
1200 if (TYPE_PTRMEMFUNC_P (t2))
1201 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
1202
1203 /* Different classes of types can't be compatible. */
1204 if (TREE_CODE (t1) != TREE_CODE (t2))
1205 return false;
1206
1207 /* Qualifiers must match. For array types, we will check when we
1208 recur on the array element types. */
1209 if (TREE_CODE (t1) != ARRAY_TYPE
1210 && cp_type_quals (t1) != cp_type_quals (t2))
1211 return false;
1212 if (TREE_CODE (t1) == FUNCTION_TYPE
1213 && type_memfn_quals (t1) != type_memfn_quals (t2))
1214 return false;
1215 /* Need to check this before TYPE_MAIN_VARIANT.
1216 FIXME function qualifiers should really change the main variant. */
1217 if (TREE_CODE (t1) == FUNCTION_TYPE
1218 || TREE_CODE (t1) == METHOD_TYPE)
1219 {
1220 if (type_memfn_rqual (t1) != type_memfn_rqual (t2))
1221 return false;
1222 if (flag_noexcept_type
1223 && !comp_except_specs (TYPE_RAISES_EXCEPTIONS (t1),
1224 TYPE_RAISES_EXCEPTIONS (t2),
1225 ce_type))
1226 return false;
1227 }
1228
1229 /* Allow for two different type nodes which have essentially the same
1230 definition. Note that we already checked for equality of the type
1231 qualifiers (just above). */
1232
1233 if (TREE_CODE (t1) != ARRAY_TYPE
1234 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
1235 return true;
1236
1237
1238 /* Compare the types. Break out if they could be the same. */
1239 switch (TREE_CODE (t1))
1240 {
1241 case VOID_TYPE:
1242 case BOOLEAN_TYPE:
1243 /* All void and bool types are the same. */
1244 break;
1245
1246 case INTEGER_TYPE:
1247 case FIXED_POINT_TYPE:
1248 case REAL_TYPE:
1249 /* With these nodes, we can't determine type equivalence by
1250 looking at what is stored in the nodes themselves, because
1251 two nodes might have different TYPE_MAIN_VARIANTs but still
1252 represent the same type. For example, wchar_t and int could
1253 have the same properties (TYPE_PRECISION, TYPE_MIN_VALUE,
1254 TYPE_MAX_VALUE, etc.), but have different TYPE_MAIN_VARIANTs
1255 and are distinct types. On the other hand, int and the
1256 following typedef
1257
1258 typedef int INT __attribute((may_alias));
1259
1260 have identical properties, different TYPE_MAIN_VARIANTs, but
1261 represent the same type. The canonical type system keeps
1262 track of equivalence in this case, so we fall back on it. */
1263 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1264
1265 case TEMPLATE_TEMPLATE_PARM:
1266 case BOUND_TEMPLATE_TEMPLATE_PARM:
1267 if (!comp_template_parms_position (t1, t2))
1268 return false;
1269 if (!comp_template_parms
1270 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1271 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1272 return false;
1273 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1274 break;
1275 /* Don't check inheritance. */
1276 strict = COMPARE_STRICT;
1277 /* Fall through. */
1278
1279 case RECORD_TYPE:
1280 case UNION_TYPE:
1281 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1282 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1283 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1284 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1285 break;
1286
1287 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1288 break;
1289 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1290 break;
1291
1292 return false;
1293
1294 case OFFSET_TYPE:
1295 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1296 strict & ~COMPARE_REDECLARATION))
1297 return false;
1298 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1299 return false;
1300 break;
1301
1302 case REFERENCE_TYPE:
1303 if (TYPE_REF_IS_RVALUE (t1) != TYPE_REF_IS_RVALUE (t2))
1304 return false;
1305 /* fall through to checks for pointer types */
1306 gcc_fallthrough ();
1307
1308 case POINTER_TYPE:
1309 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1310 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1311 return false;
1312 break;
1313
1314 case METHOD_TYPE:
1315 case FUNCTION_TYPE:
1316 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1317 return false;
1318 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1319 return false;
1320 break;
1321
1322 case ARRAY_TYPE:
1323 /* Target types must match incl. qualifiers. */
1324 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1325 return false;
1326 break;
1327
1328 case TEMPLATE_TYPE_PARM:
1329 /* If T1 and T2 don't have the same relative position in their
1330 template parameters set, they can't be equal. */
1331 if (!comp_template_parms_position (t1, t2))
1332 return false;
1333 /* Constrained 'auto's are distinct from parms that don't have the same
1334 constraints. */
1335 if (!equivalent_placeholder_constraints (t1, t2))
1336 return false;
1337 break;
1338
1339 case TYPENAME_TYPE:
1340 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1341 TYPENAME_TYPE_FULLNAME (t2)))
1342 return false;
1343 /* Qualifiers don't matter on scopes. */
1344 if (!same_type_ignoring_top_level_qualifiers_p (TYPE_CONTEXT (t1),
1345 TYPE_CONTEXT (t2)))
1346 return false;
1347 break;
1348
1349 case UNBOUND_CLASS_TEMPLATE:
1350 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1351 return false;
1352 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1353 return false;
1354 break;
1355
1356 case COMPLEX_TYPE:
1357 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1358 return false;
1359 break;
1360
1361 case VECTOR_TYPE:
1362 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1363 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1364 return false;
1365 break;
1366
1367 case TYPE_PACK_EXPANSION:
1368 return (same_type_p (PACK_EXPANSION_PATTERN (t1),
1369 PACK_EXPANSION_PATTERN (t2))
1370 && comp_template_args (PACK_EXPANSION_EXTRA_ARGS (t1),
1371 PACK_EXPANSION_EXTRA_ARGS (t2)));
1372
1373 case DECLTYPE_TYPE:
1374 if (DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t1)
1375 != DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t2)
1376 || (DECLTYPE_FOR_LAMBDA_CAPTURE (t1)
1377 != DECLTYPE_FOR_LAMBDA_CAPTURE (t2))
1378 || (DECLTYPE_FOR_LAMBDA_PROXY (t1)
1379 != DECLTYPE_FOR_LAMBDA_PROXY (t2))
1380 || !cp_tree_equal (DECLTYPE_TYPE_EXPR (t1),
1381 DECLTYPE_TYPE_EXPR (t2)))
1382 return false;
1383 break;
1384
1385 case UNDERLYING_TYPE:
1386 return same_type_p (UNDERLYING_TYPE_TYPE (t1),
1387 UNDERLYING_TYPE_TYPE (t2));
1388
1389 default:
1390 return false;
1391 }
1392
1393 /* If we get here, we know that from a target independent POV the
1394 types are the same. Make sure the target attributes are also
1395 the same. */
1396 return comp_type_attributes (t1, t2);
1397}
1398
1399/* Return true if T1 and T2 are related as allowed by STRICT. STRICT
1400 is a bitwise-or of the COMPARE_* flags. */
1401
1402bool
1403comptypes (tree t1, tree t2, int strict)
1404{
1405 if (strict == COMPARE_STRICT)
1406 {
1407 if (t1 == t2)
1408 return true;
1409
1410 if (t1 == error_mark_node || t2 == error_mark_node)
1411 return false;
1412
1413 if (TYPE_STRUCTURAL_EQUALITY_P (t1) || TYPE_STRUCTURAL_EQUALITY_P (t2))
1414 /* At least one of the types requires structural equality, so
1415 perform a deep check. */
1416 return structural_comptypes (t1, t2, strict);
1417
1418 if (flag_checking && USE_CANONICAL_TYPES)
1419 {
1420 bool result = structural_comptypes (t1, t2, strict);
1421
1422 if (result && TYPE_CANONICAL (t1) != TYPE_CANONICAL (t2))
1423 /* The two types are structurally equivalent, but their
1424 canonical types were different. This is a failure of the
1425 canonical type propagation code.*/
1426 internal_error
1427 ("canonical types differ for identical types %qT and %qT",
1428 t1, t2);
1429 else if (!result && TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2))
1430 /* Two types are structurally different, but the canonical
1431 types are the same. This means we were over-eager in
1432 assigning canonical types. */
1433 internal_error
1434 ("same canonical type node for different types %qT and %qT",
1435 t1, t2);
1436
1437 return result;
1438 }
1439 if (!flag_checking && USE_CANONICAL_TYPES)
1440 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1441 else
1442 return structural_comptypes (t1, t2, strict);
1443 }
1444 else if (strict == COMPARE_STRUCTURAL)
1445 return structural_comptypes (t1, t2, COMPARE_STRICT);
1446 else
1447 return structural_comptypes (t1, t2, strict);
1448}
1449
1450/* Returns nonzero iff TYPE1 and TYPE2 are the same type, ignoring
1451 top-level qualifiers. */
1452
1453bool
1454same_type_ignoring_top_level_qualifiers_p (tree type1, tree type2)
1455{
1456 if (type1 == error_mark_node || type2 == error_mark_node)
1457 return false;
1458
1459 type1 = cp_build_qualified_type (type1, TYPE_UNQUALIFIED);
1460 type2 = cp_build_qualified_type (type2, TYPE_UNQUALIFIED);
1461 return same_type_p (type1, type2);
1462}
1463
1464/* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1465
1466bool
1467at_least_as_qualified_p (const_tree type1, const_tree type2)
1468{
1469 int q1 = cp_type_quals (type1);
1470 int q2 = cp_type_quals (type2);
1471
1472 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1473 return (q1 & q2) == q2;
1474}
1475
1476/* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1477 more cv-qualified that TYPE1, and 0 otherwise. */
1478
1479int
1480comp_cv_qualification (int q1, int q2)
1481{
1482 if (q1 == q2)
1483 return 0;
1484
1485 if ((q1 & q2) == q2)
1486 return 1;
1487 else if ((q1 & q2) == q1)
1488 return -1;
1489
1490 return 0;
1491}
1492
1493int
1494comp_cv_qualification (const_tree type1, const_tree type2)
1495{
1496 int q1 = cp_type_quals (type1);
1497 int q2 = cp_type_quals (type2);
1498 return comp_cv_qualification (q1, q2);
1499}
1500
1501/* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1502 subset of the cv-qualification signature of TYPE2, and the types
1503 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1504
1505int
1506comp_cv_qual_signature (tree type1, tree type2)
1507{
1508 if (comp_ptr_ttypes_real (type2, type1, -1))
1509 return 1;
1510 else if (comp_ptr_ttypes_real (type1, type2, -1))
1511 return -1;
1512 else
1513 return 0;
1514}
1515
1516/* Subroutines of `comptypes'. */
1517
1518/* Return true if two parameter type lists PARMS1 and PARMS2 are
1519 equivalent in the sense that functions with those parameter types
1520 can have equivalent types. The two lists must be equivalent,
1521 element by element. */
1522
1523bool
1524compparms (const_tree parms1, const_tree parms2)
1525{
1526 const_tree t1, t2;
1527
1528 /* An unspecified parmlist matches any specified parmlist
1529 whose argument types don't need default promotions. */
1530
1531 for (t1 = parms1, t2 = parms2;
1532 t1 || t2;
1533 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1534 {
1535 /* If one parmlist is shorter than the other,
1536 they fail to match. */
1537 if (!t1 || !t2)
1538 return false;
1539 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1540 return false;
1541 }
1542 return true;
1543}
1544
1545
1546/* Process a sizeof or alignof expression where the operand is a
1547 type. */
1548
1549tree
1550cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1551{
1552 tree value;
1553 bool dependent_p;
1554
1555 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1556 if (type == error_mark_node)
1557 return error_mark_node;
1558
1559 type = non_reference (type);
1560 if (TREE_CODE (type) == METHOD_TYPE)
1561 {
1562 if (complain)
1563 pedwarn (input_location, OPT_Wpointer_arith,
1564 "invalid application of %qs to a member function",
1565 OVL_OP_INFO (false, op)->name);
1566 else
1567 return error_mark_node;
1568 value = size_one_node;
1569 }
1570
1571 dependent_p = dependent_type_p (type);
1572 if (!dependent_p)
1573 complete_type (type);
1574 if (dependent_p
1575 /* VLA types will have a non-constant size. In the body of an
1576 uninstantiated template, we don't need to try to compute the
1577 value, because the sizeof expression is not an integral
1578 constant expression in that case. And, if we do try to
1579 compute the value, we'll likely end up with SAVE_EXPRs, which
1580 the template substitution machinery does not expect to see. */
1581 || (processing_template_decl
1582 && COMPLETE_TYPE_P (type)
1583 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST))
1584 {
1585 value = build_min (op, size_type_node, type);
1586 TREE_READONLY (value) = 1;
1587 return value;
1588 }
1589
1590 return c_sizeof_or_alignof_type (input_location, complete_type (type),
1591 op == SIZEOF_EXPR, false,
1592 complain);
1593}
1594
1595/* Return the size of the type, without producing any warnings for
1596 types whose size cannot be taken. This routine should be used only
1597 in some other routine that has already produced a diagnostic about
1598 using the size of such a type. */
1599tree
1600cxx_sizeof_nowarn (tree type)
1601{
1602 if (TREE_CODE (type) == FUNCTION_TYPE
1603 || VOID_TYPE_P (type)
1604 || TREE_CODE (type) == ERROR_MARK)
1605 return size_one_node;
1606 else if (!COMPLETE_TYPE_P (type))
1607 return size_zero_node;
1608 else
1609 return cxx_sizeof_or_alignof_type (type, SIZEOF_EXPR, false);
1610}
1611
1612/* Process a sizeof expression where the operand is an expression. */
1613
1614static tree
1615cxx_sizeof_expr (tree e, tsubst_flags_t complain)
1616{
1617 if (e == error_mark_node)
1618 return error_mark_node;
1619
1620 if (processing_template_decl)
1621 {
1622 e = build_min (SIZEOF_EXPR, size_type_node, e);
1623 TREE_SIDE_EFFECTS (e) = 0;
1624 TREE_READONLY (e) = 1;
1625
1626 return e;
1627 }
1628
1629 /* To get the size of a static data member declared as an array of
1630 unknown bound, we need to instantiate it. */
1631 if (VAR_P (e)
1632 && VAR_HAD_UNKNOWN_BOUND (e)
1633 && DECL_TEMPLATE_INSTANTIATION (e))
1634 instantiate_decl (e, /*defer_ok*/true, /*expl_inst_mem*/false);
1635
1636 if (TREE_CODE (e) == PARM_DECL
1637 && DECL_ARRAY_PARAMETER_P (e)
1638 && (complain & tf_warning))
1639 {
1640 if (warning (OPT_Wsizeof_array_argument, "%<sizeof%> on array function "
1641 "parameter %qE will return size of %qT", e, TREE_TYPE (e)))
1642 inform (DECL_SOURCE_LOCATION (e), "declared here");
1643 }
1644
1645 e = mark_type_use (e);
1646
1647 if (bitfield_p (e))
1648 {
1649 if (complain & tf_error)
1650 error ("invalid application of %<sizeof%> to a bit-field");
1651 else
1652 return error_mark_node;
1653 e = char_type_node;
1654 }
1655 else if (is_overloaded_fn (e))
1656 {
1657 if (complain & tf_error)
1658 permerror (input_location, "ISO C++ forbids applying %<sizeof%> to an expression of "
1659 "function type");
1660 else
1661 return error_mark_node;
1662 e = char_type_node;
1663 }
1664 else if (type_unknown_p (e))
1665 {
1666 if (complain & tf_error)
1667 cxx_incomplete_type_error (e, TREE_TYPE (e));
1668 else
1669 return error_mark_node;
1670 e = char_type_node;
1671 }
1672 else
1673 e = TREE_TYPE (e);
1674
1675 return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, complain & tf_error);
1676}
1677
1678/* Implement the __alignof keyword: Return the minimum required
1679 alignment of E, measured in bytes. For VAR_DECL's and
1680 FIELD_DECL's return DECL_ALIGN (which can be set from an
1681 "aligned" __attribute__ specification). */
1682
1683static tree
1684cxx_alignof_expr (tree e, tsubst_flags_t complain)
1685{
1686 tree t;
1687
1688 if (e == error_mark_node)
1689 return error_mark_node;
1690
1691 if (processing_template_decl)
1692 {
1693 e = build_min (ALIGNOF_EXPR, size_type_node, e);
1694 TREE_SIDE_EFFECTS (e) = 0;
1695 TREE_READONLY (e) = 1;
1696
1697 return e;
1698 }
1699
1700 e = mark_type_use (e);
1701
1702 if (VAR_P (e))
1703 t = size_int (DECL_ALIGN_UNIT (e));
1704 else if (bitfield_p (e))
1705 {
1706 if (complain & tf_error)
1707 error ("invalid application of %<__alignof%> to a bit-field");
1708 else
1709 return error_mark_node;
1710 t = size_one_node;
1711 }
1712 else if (TREE_CODE (e) == COMPONENT_REF
1713 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL)
1714 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1)));
1715 else if (is_overloaded_fn (e))
1716 {
1717 if (complain & tf_error)
1718 permerror (input_location, "ISO C++ forbids applying %<__alignof%> to an expression of "
1719 "function type");
1720 else
1721 return error_mark_node;
1722 if (TREE_CODE (e) == FUNCTION_DECL)
1723 t = size_int (DECL_ALIGN_UNIT (e));
1724 else
1725 t = size_one_node;
1726 }
1727 else if (type_unknown_p (e))
1728 {
1729 if (complain & tf_error)
1730 cxx_incomplete_type_error (e, TREE_TYPE (e));
1731 else
1732 return error_mark_node;
1733 t = size_one_node;
1734 }
1735 else
1736 return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR,
1737 complain & tf_error);
1738
1739 return fold_convert (size_type_node, t);
1740}
1741
1742/* Process a sizeof or alignof expression E with code OP where the operand
1743 is an expression. */
1744
1745tree
1746cxx_sizeof_or_alignof_expr (tree e, enum tree_code op, bool complain)
1747{
1748 if (op == SIZEOF_EXPR)
1749 return cxx_sizeof_expr (e, complain? tf_warning_or_error : tf_none);
1750 else
1751 return cxx_alignof_expr (e, complain? tf_warning_or_error : tf_none);
1752}
1753
1754/* Build a representation of an expression 'alignas(E).' Return the
1755 folded integer value of E if it is an integral constant expression
1756 that resolves to a valid alignment. If E depends on a template
1757 parameter, return a syntactic representation tree of kind
1758 ALIGNOF_EXPR. Otherwise, return an error_mark_node if the
1759 expression is ill formed, or NULL_TREE if E is NULL_TREE. */
1760
1761tree
1762cxx_alignas_expr (tree e)
1763{
1764 if (e == NULL_TREE || e == error_mark_node
1765 || (!TYPE_P (e) && !require_potential_rvalue_constant_expression (e)))
1766 return e;
1767
1768 if (TYPE_P (e))
1769 /* [dcl.align]/3:
1770
1771 When the alignment-specifier is of the form
1772 alignas(type-id ), it shall have the same effect as
1773 alignas(alignof(type-id )). */
1774
1775 return cxx_sizeof_or_alignof_type (e, ALIGNOF_EXPR, false);
1776
1777 /* If we reach this point, it means the alignas expression if of
1778 the form "alignas(assignment-expression)", so we should follow
1779 what is stated by [dcl.align]/2. */
1780
1781 if (value_dependent_expression_p (e))
1782 /* Leave value-dependent expression alone for now. */
1783 return e;
1784
1785 e = instantiate_non_dependent_expr (e);
1786 e = mark_rvalue_use (e);
1787
1788 /* [dcl.align]/2 says:
1789
1790 the assignment-expression shall be an integral constant
1791 expression. */
1792
1793 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (e)))
1794 {
1795 error ("%<alignas%> argument has non-integral type %qT", TREE_TYPE (e));
1796 return error_mark_node;
1797 }
1798
1799 return cxx_constant_value (e);
1800}
1801
1802
1803/* EXPR is being used in a context that is not a function call.
1804 Enforce:
1805
1806 [expr.ref]
1807
1808 The expression can be used only as the left-hand operand of a
1809 member function call.
1810
1811 [expr.mptr.operator]
1812
1813 If the result of .* or ->* is a function, then that result can be
1814 used only as the operand for the function call operator ().
1815
1816 by issuing an error message if appropriate. Returns true iff EXPR
1817 violates these rules. */
1818
1819bool
1820invalid_nonstatic_memfn_p (location_t loc, tree expr, tsubst_flags_t complain)
1821{
1822 if (expr == NULL_TREE)
1823 return false;
1824 /* Don't enforce this in MS mode. */
1825 if (flag_ms_extensions)
1826 return false;
1827 if (is_overloaded_fn (expr) && !really_overloaded_fn (expr))
1828 expr = get_first_fn (expr);
1829 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (expr))
1830 {
1831 if (complain & tf_error)
1832 {
1833 if (DECL_P (expr))
1834 {
1835 error_at (loc, "invalid use of non-static member function %qD",
1836 expr);
1837 inform (DECL_SOURCE_LOCATION (expr), "declared here");
1838 }
1839 else
1840 error_at (loc, "invalid use of non-static member function of "
1841 "type %qT", TREE_TYPE (expr));
1842 }
1843 return true;
1844 }
1845 return false;
1846}
1847
1848/* If EXP is a reference to a bitfield, and the type of EXP does not
1849 match the declared type of the bitfield, return the declared type
1850 of the bitfield. Otherwise, return NULL_TREE. */
1851
1852tree
1853is_bitfield_expr_with_lowered_type (const_tree exp)
1854{
1855 switch (TREE_CODE (exp))
1856 {
1857 case COND_EXPR:
1858 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)
1859 ? TREE_OPERAND (exp, 1)
1860 : TREE_OPERAND (exp, 0)))
1861 return NULL_TREE;
1862 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2));
1863
1864 case COMPOUND_EXPR:
1865 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1));
1866
1867 case MODIFY_EXPR:
1868 case SAVE_EXPR:
1869 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1870
1871 case COMPONENT_REF:
1872 {
1873 tree field;
1874
1875 field = TREE_OPERAND (exp, 1);
1876 if (TREE_CODE (field) != FIELD_DECL || !DECL_BIT_FIELD_TYPE (field))
1877 return NULL_TREE;
1878 if (same_type_ignoring_top_level_qualifiers_p
1879 (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field)))
1880 return NULL_TREE;
1881 return DECL_BIT_FIELD_TYPE (field);
1882 }
1883
1884 case VAR_DECL:
1885 if (DECL_HAS_VALUE_EXPR_P (exp))
1886 return is_bitfield_expr_with_lowered_type (DECL_VALUE_EXPR
1887 (CONST_CAST_TREE (exp)));
1888 return NULL_TREE;
1889
1890 CASE_CONVERT:
1891 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (exp, 0)))
1892 == TYPE_MAIN_VARIANT (TREE_TYPE (exp)))
1893 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1894 /* Fallthrough. */
1895
1896 default:
1897 return NULL_TREE;
1898 }
1899}
1900
1901/* Like is_bitfield_with_lowered_type, except that if EXP is not a
1902 bitfield with a lowered type, the type of EXP is returned, rather
1903 than NULL_TREE. */
1904
1905tree
1906unlowered_expr_type (const_tree exp)
1907{
1908 tree type;
1909 tree etype = TREE_TYPE (exp);
1910
1911 type = is_bitfield_expr_with_lowered_type (exp);
1912 if (type)
1913 type = cp_build_qualified_type (type, cp_type_quals (etype));
1914 else
1915 type = etype;
1916
1917 return type;
1918}
1919
1920/* Perform the conversions in [expr] that apply when an lvalue appears
1921 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1922 function-to-pointer conversions. In addition, bitfield references are
1923 converted to their declared types. Note that this function does not perform
1924 the lvalue-to-rvalue conversion for class types. If you need that conversion
1925 for class types, then you probably need to use force_rvalue.
1926
1927 Although the returned value is being used as an rvalue, this
1928 function does not wrap the returned expression in a
1929 NON_LVALUE_EXPR; the caller is expected to be mindful of the fact
1930 that the return value is no longer an lvalue. */
1931
1932tree
1933decay_conversion (tree exp,
1934 tsubst_flags_t complain,
1935 bool reject_builtin /* = true */)
1936{
1937 tree type;
1938 enum tree_code code;
1939 location_t loc = EXPR_LOC_OR_LOC (exp, input_location);
1940
1941 type = TREE_TYPE (exp);
1942 if (type == error_mark_node)
1943 return error_mark_node;
1944
1945 exp = resolve_nondeduced_context (exp, complain);
1946 if (type_unknown_p (exp))
1947 {
1948 if (complain & tf_error)
1949 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1950 return error_mark_node;
1951 }
1952
1953 code = TREE_CODE (type);
1954
1955 if (error_operand_p (exp))
1956 return error_mark_node;
1957
1958 if (NULLPTR_TYPE_P (type) && !TREE_SIDE_EFFECTS (exp))
1959 return nullptr_node;
1960
1961 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1962 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1963 if (code == VOID_TYPE)
1964 {
1965 if (complain & tf_error)
1966 error_at (loc, "void value not ignored as it ought to be");
1967 return error_mark_node;
1968 }
1969 if (invalid_nonstatic_memfn_p (loc, exp, complain))
1970 return error_mark_node;
1971 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1972 {
1973 exp = mark_lvalue_use (exp);
1974 if (reject_builtin && reject_gcc_builtin (exp, loc))
1975 return error_mark_node;
1976 return cp_build_addr_expr (exp, complain);
1977 }
1978 if (code == ARRAY_TYPE)
1979 {
1980 tree adr;
1981 tree ptrtype;
1982
1983 exp = mark_lvalue_use (exp);
1984
1985 if (INDIRECT_REF_P (exp))
1986 return build_nop (build_pointer_type (TREE_TYPE (type)),
1987 TREE_OPERAND (exp, 0));
1988
1989 if (TREE_CODE (exp) == COMPOUND_EXPR)
1990 {
1991 tree op1 = decay_conversion (TREE_OPERAND (exp, 1), complain);
1992 if (op1 == error_mark_node)
1993 return error_mark_node;
1994 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1995 TREE_OPERAND (exp, 0), op1);
1996 }
1997
1998 if (!obvalue_p (exp)
1999 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
2000 {
2001 if (complain & tf_error)
2002 error_at (loc, "invalid use of non-lvalue array");
2003 return error_mark_node;
2004 }
2005
2006 /* Don't let an array compound literal decay to a pointer. It can
2007 still be used to initialize an array or bind to a reference. */
2008 if (TREE_CODE (exp) == TARGET_EXPR)
2009 {
2010 if (complain & tf_error)
2011 error_at (loc, "taking address of temporary array");
2012 return error_mark_node;
2013 }
2014
2015 ptrtype = build_pointer_type (TREE_TYPE (type));
2016
2017 if (VAR_P (exp))
2018 {
2019 if (!cxx_mark_addressable (exp))
2020 return error_mark_node;
2021 adr = build_nop (ptrtype, build_address (exp));
2022 return adr;
2023 }
2024 /* This way is better for a COMPONENT_REF since it can
2025 simplify the offset for a component. */
2026 adr = cp_build_addr_expr (exp, complain);
2027 return cp_convert (ptrtype, adr, complain);
2028 }
2029
2030 /* Otherwise, it's the lvalue-to-rvalue conversion. */
2031 exp = mark_rvalue_use (exp, loc, reject_builtin);
2032
2033 /* If a bitfield is used in a context where integral promotion
2034 applies, then the caller is expected to have used
2035 default_conversion. That function promotes bitfields correctly
2036 before calling this function. At this point, if we have a
2037 bitfield referenced, we may assume that is not subject to
2038 promotion, and that, therefore, the type of the resulting rvalue
2039 is the declared type of the bitfield. */
2040 exp = convert_bitfield_to_declared_type (exp);
2041
2042 /* We do not call rvalue() here because we do not want to wrap EXP
2043 in a NON_LVALUE_EXPR. */
2044
2045 /* [basic.lval]
2046
2047 Non-class rvalues always have cv-unqualified types. */
2048 type = TREE_TYPE (exp);
2049 if (!CLASS_TYPE_P (type) && cv_qualified_p (type))
2050 exp = build_nop (cv_unqualified (type), exp);
2051
2052 if (!complete_type_or_maybe_complain (type, exp, complain))
2053 return error_mark_node;
2054
2055 return exp;
2056}
2057
2058/* Perform preparatory conversions, as part of the "usual arithmetic
2059 conversions". In particular, as per [expr]:
2060
2061 Whenever an lvalue expression appears as an operand of an
2062 operator that expects the rvalue for that operand, the
2063 lvalue-to-rvalue, array-to-pointer, or function-to-pointer
2064 standard conversions are applied to convert the expression to an
2065 rvalue.
2066
2067 In addition, we perform integral promotions here, as those are
2068 applied to both operands to a binary operator before determining
2069 what additional conversions should apply. */
2070
2071static tree
2072cp_default_conversion (tree exp, tsubst_flags_t complain)
2073{
2074 /* Check for target-specific promotions. */
2075 tree promoted_type = targetm.promoted_type (TREE_TYPE (exp));
2076 if (promoted_type)
2077 exp = cp_convert (promoted_type, exp, complain);
2078 /* Perform the integral promotions first so that bitfield
2079 expressions (which may promote to "int", even if the bitfield is
2080 declared "unsigned") are promoted correctly. */
2081 else if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
2082 exp = cp_perform_integral_promotions (exp, complain);
2083 /* Perform the other conversions. */
2084 exp = decay_conversion (exp, complain);
2085
2086 return exp;
2087}
2088
2089/* C version. */
2090
2091tree
2092default_conversion (tree exp)
2093{
2094 return cp_default_conversion (exp, tf_warning_or_error);
2095}
2096
2097/* EXPR is an expression with an integral or enumeration type.
2098 Perform the integral promotions in [conv.prom], and return the
2099 converted value. */
2100
2101tree
2102cp_perform_integral_promotions (tree expr, tsubst_flags_t complain)
2103{
2104 tree type;
2105 tree promoted_type;
2106
2107 expr = mark_rvalue_use (expr);
2108
2109 /* [conv.prom]
2110
2111 If the bitfield has an enumerated type, it is treated as any
2112 other value of that type for promotion purposes. */
2113 type = is_bitfield_expr_with_lowered_type (expr);
2114 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
2115 type = TREE_TYPE (expr);
2116 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
2117 /* Scoped enums don't promote. */
2118 if (SCOPED_ENUM_P (type))
2119 return expr;
2120 promoted_type = type_promotes_to (type);
2121 if (type != promoted_type)
2122 expr = cp_convert (promoted_type, expr, complain);
2123 return expr;
2124}
2125
2126/* C version. */
2127
2128tree
2129perform_integral_promotions (tree expr)
2130{
2131 return cp_perform_integral_promotions (expr, tf_warning_or_error);
2132}
2133
2134/* Returns nonzero iff exp is a STRING_CST or the result of applying
2135 decay_conversion to one. */
2136
2137int
2138string_conv_p (const_tree totype, const_tree exp, int warn)
2139{
2140 tree t;
2141
2142 if (!TYPE_PTR_P (totype))
2143 return 0;
2144
2145 t = TREE_TYPE (totype);
2146 if (!same_type_p (t, char_type_node)
2147 && !same_type_p (t, char16_type_node)
2148 && !same_type_p (t, char32_type_node)
2149 && !same_type_p (t, wchar_type_node))
2150 return 0;
2151
2152 if (TREE_CODE (exp) == STRING_CST)
2153 {
2154 /* Make sure that we don't try to convert between char and wide chars. */
2155 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
2156 return 0;
2157 }
2158 else
2159 {
2160 /* Is this a string constant which has decayed to 'const char *'? */
2161 t = build_pointer_type (cp_build_qualified_type (t, TYPE_QUAL_CONST));
2162 if (!same_type_p (TREE_TYPE (exp), t))
2163 return 0;
2164 STRIP_NOPS (exp);
2165 if (TREE_CODE (exp) != ADDR_EXPR
2166 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
2167 return 0;
2168 }
2169 if (warn)
2170 {
2171 if (cxx_dialect >= cxx11)
2172 pedwarn (input_location, OPT_Wwrite_strings,
2173 "ISO C++ forbids converting a string constant to %qT",
2174 totype);
2175 else
2176 warning (OPT_Wwrite_strings,
2177 "deprecated conversion from string constant to %qT",
2178 totype);
2179 }
2180
2181 return 1;
2182}
2183
2184/* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
2185 can, for example, use as an lvalue. This code used to be in
2186 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
2187 expressions, where we're dealing with aggregates. But now it's again only
2188 called from unary_complex_lvalue. The case (in particular) that led to
2189 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
2190 get it there. */
2191
2192static tree
2193rationalize_conditional_expr (enum tree_code code, tree t,
2194 tsubst_flags_t complain)
2195{
2196 location_t loc = EXPR_LOC_OR_LOC (t, input_location);
2197
2198 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
2199 the first operand is always the one to be used if both operands
2200 are equal, so we know what conditional expression this used to be. */
2201 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
2202 {
2203 tree op0 = TREE_OPERAND (t, 0);
2204 tree op1 = TREE_OPERAND (t, 1);
2205
2206 /* The following code is incorrect if either operand side-effects. */
2207 gcc_assert (!TREE_SIDE_EFFECTS (op0)
2208 && !TREE_SIDE_EFFECTS (op1));
2209 return
2210 build_conditional_expr (loc,
2211 build_x_binary_op (loc,
2212 (TREE_CODE (t) == MIN_EXPR
2213 ? LE_EXPR : GE_EXPR),
2214 op0, TREE_CODE (op0),
2215 op1, TREE_CODE (op1),
2216 /*overload=*/NULL,
2217 complain),
2218 cp_build_unary_op (code, op0, false, complain),
2219 cp_build_unary_op (code, op1, false, complain),
2220 complain);
2221 }
2222
2223 return
2224 build_conditional_expr (loc, TREE_OPERAND (t, 0),
2225 cp_build_unary_op (code, TREE_OPERAND (t, 1), false,
2226 complain),
2227 cp_build_unary_op (code, TREE_OPERAND (t, 2), false,
2228 complain),
2229 complain);
2230}
2231
2232/* Given the TYPE of an anonymous union field inside T, return the
2233 FIELD_DECL for the field. If not found return NULL_TREE. Because
2234 anonymous unions can nest, we must also search all anonymous unions
2235 that are directly reachable. */
2236
2237tree
2238lookup_anon_field (tree t, tree type)
2239{
2240 tree field;
2241
2242 t = TYPE_MAIN_VARIANT (t);
2243
2244 for (field = TYPE_FIELDS (t); field; field = DECL_CHAIN (field))
2245 {
2246 if (TREE_STATIC (field))
2247 continue;
2248 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
2249 continue;
2250
2251 /* If we find it directly, return the field. */
2252 if (DECL_NAME (field) == NULL_TREE
2253 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
2254 {
2255 return field;
2256 }
2257
2258 /* Otherwise, it could be nested, search harder. */
2259 if (DECL_NAME (field) == NULL_TREE
2260 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2261 {
2262 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
2263 if (subfield)
2264 return subfield;
2265 }
2266 }
2267 return NULL_TREE;
2268}
2269
2270/* Build an expression representing OBJECT.MEMBER. OBJECT is an
2271 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
2272 non-NULL, it indicates the path to the base used to name MEMBER.
2273 If PRESERVE_REFERENCE is true, the expression returned will have
2274 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
2275 returned will have the type referred to by the reference.
2276
2277 This function does not perform access control; that is either done
2278 earlier by the parser when the name of MEMBER is resolved to MEMBER
2279 itself, or later when overload resolution selects one of the
2280 functions indicated by MEMBER. */
2281
2282tree
2283build_class_member_access_expr (cp_expr object, tree member,
2284 tree access_path, bool preserve_reference,
2285 tsubst_flags_t complain)
2286{
2287 tree object_type;
2288 tree member_scope;
2289 tree result = NULL_TREE;
2290 tree using_decl = NULL_TREE;
2291
2292 if (error_operand_p (object) || error_operand_p (member))
2293 return error_mark_node;
2294
2295 gcc_assert (DECL_P (member) || BASELINK_P (member));
2296
2297 /* [expr.ref]
2298
2299 The type of the first expression shall be "class object" (of a
2300 complete type). */
2301 object_type = TREE_TYPE (object);
2302 if (!currently_open_class (object_type)
2303 && !complete_type_or_maybe_complain (object_type, object, complain))
2304 return error_mark_node;
2305 if (!CLASS_TYPE_P (object_type))
2306 {
2307 if (complain & tf_error)
2308 {
2309 if (POINTER_TYPE_P (object_type)
2310 && CLASS_TYPE_P (TREE_TYPE (object_type)))
2311 error ("request for member %qD in %qE, which is of pointer "
2312 "type %qT (maybe you meant to use %<->%> ?)",
2313 member, object.get_value (), object_type);
2314 else
2315 error ("request for member %qD in %qE, which is of non-class "
2316 "type %qT", member, object.get_value (), object_type);
2317 }
2318 return error_mark_node;
2319 }
2320
2321 /* The standard does not seem to actually say that MEMBER must be a
2322 member of OBJECT_TYPE. However, that is clearly what is
2323 intended. */
2324 if (DECL_P (member))
2325 {
2326 member_scope = DECL_CLASS_CONTEXT (member);
2327 if (!mark_used (member, complain) && !(complain & tf_error))
2328 return error_mark_node;
2329 if (TREE_DEPRECATED (member))
2330 warn_deprecated_use (member, NULL_TREE);
2331 }
2332 else
2333 member_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (member));
2334 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
2335 presently be the anonymous union. Go outwards until we find a
2336 type related to OBJECT_TYPE. */
2337 while ((ANON_AGGR_TYPE_P (member_scope) || UNSCOPED_ENUM_P (member_scope))
2338 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
2339 object_type))
2340 member_scope = TYPE_CONTEXT (member_scope);
2341 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
2342 {
2343 if (complain & tf_error)
2344 {
2345 if (TREE_CODE (member) == FIELD_DECL)
2346 error ("invalid use of nonstatic data member %qE", member);
2347 else
2348 error ("%qD is not a member of %qT", member, object_type);
2349 }
2350 return error_mark_node;
2351 }
2352
2353 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
2354 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
2355 in the front end; only _DECLs and _REFs are lvalues in the back end. */
2356 {
2357 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
2358 if (temp)
2359 object = cp_build_fold_indirect_ref (temp);
2360 }
2361
2362 /* In [expr.ref], there is an explicit list of the valid choices for
2363 MEMBER. We check for each of those cases here. */
2364 if (VAR_P (member))
2365 {
2366 /* A static data member. */
2367 result = member;
2368 mark_exp_read (object);
2369 /* If OBJECT has side-effects, they are supposed to occur. */
2370 if (TREE_SIDE_EFFECTS (object))
2371 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
2372 }
2373 else if (TREE_CODE (member) == FIELD_DECL)
2374 {
2375 /* A non-static data member. */
2376 bool null_object_p;
2377 int type_quals;
2378 tree member_type;
2379
2380 if (INDIRECT_REF_P (object))
2381 null_object_p =
2382 integer_zerop (tree_strip_nop_conversions (TREE_OPERAND (object, 0)));
2383 else
2384 null_object_p = false;
2385
2386 /* Convert OBJECT to the type of MEMBER. */
2387 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
2388 TYPE_MAIN_VARIANT (member_scope)))
2389 {
2390 tree binfo;
2391 base_kind kind;
2392
2393 binfo = lookup_base (access_path ? access_path : object_type,
2394 member_scope, ba_unique, &kind, complain);
2395 if (binfo == error_mark_node)
2396 return error_mark_node;
2397
2398 /* It is invalid to try to get to a virtual base of a
2399 NULL object. The most common cause is invalid use of
2400 offsetof macro. */
2401 if (null_object_p && kind == bk_via_virtual)
2402 {
2403 if (complain & tf_error)
2404 {
2405 error ("invalid access to non-static data member %qD in "
2406 "virtual base of NULL object", member);
2407 }
2408 return error_mark_node;
2409 }
2410
2411 /* Convert to the base. */
2412 object = build_base_path (PLUS_EXPR, object, binfo,
2413 /*nonnull=*/1, complain);
2414 /* If we found the base successfully then we should be able
2415 to convert to it successfully. */
2416 gcc_assert (object != error_mark_node);
2417 }
2418
2419 /* If MEMBER is from an anonymous aggregate, we have converted
2420 OBJECT so that it refers to the class containing the
2421 anonymous union. Generate a reference to the anonymous union
2422 itself, and recur to find MEMBER. */
2423 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
2424 /* When this code is called from build_field_call, the
2425 object already has the type of the anonymous union.
2426 That is because the COMPONENT_REF was already
2427 constructed, and was then disassembled before calling
2428 build_field_call. After the function-call code is
2429 cleaned up, this waste can be eliminated. */
2430 && (!same_type_ignoring_top_level_qualifiers_p
2431 (TREE_TYPE (object), DECL_CONTEXT (member))))
2432 {
2433 tree anonymous_union;
2434
2435 anonymous_union = lookup_anon_field (TREE_TYPE (object),
2436 DECL_CONTEXT (member));
2437 object = build_class_member_access_expr (object,
2438 anonymous_union,
2439 /*access_path=*/NULL_TREE,
2440 preserve_reference,
2441 complain);
2442 }
2443
2444 /* Compute the type of the field, as described in [expr.ref]. */
2445 type_quals = TYPE_UNQUALIFIED;
2446 member_type = TREE_TYPE (member);
2447 if (TREE_CODE (member_type) != REFERENCE_TYPE)
2448 {
2449 type_quals = (cp_type_quals (member_type)
2450 | cp_type_quals (object_type));
2451
2452 /* A field is const (volatile) if the enclosing object, or the
2453 field itself, is const (volatile). But, a mutable field is
2454 not const, even within a const object. */
2455 if (DECL_MUTABLE_P (member))
2456 type_quals &= ~TYPE_QUAL_CONST;
2457 member_type = cp_build_qualified_type (member_type, type_quals);
2458 }
2459
2460 result = build3_loc (input_location, COMPONENT_REF, member_type,
2461 object, member, NULL_TREE);
2462
2463 /* Mark the expression const or volatile, as appropriate. Even
2464 though we've dealt with the type above, we still have to mark the
2465 expression itself. */
2466 if (type_quals & TYPE_QUAL_CONST)
2467 TREE_READONLY (result) = 1;
2468 if (type_quals & TYPE_QUAL_VOLATILE)
2469 TREE_THIS_VOLATILE (result) = 1;
2470 }
2471 else if (BASELINK_P (member))
2472 {
2473 /* The member is a (possibly overloaded) member function. */
2474 tree functions;
2475 tree type;
2476
2477 /* If the MEMBER is exactly one static member function, then we
2478 know the type of the expression. Otherwise, we must wait
2479 until overload resolution has been performed. */
2480 functions = BASELINK_FUNCTIONS (member);
2481 if (TREE_CODE (functions) == FUNCTION_DECL
2482 && DECL_STATIC_FUNCTION_P (functions))
2483 type = TREE_TYPE (functions);
2484 else
2485 type = unknown_type_node;
2486 /* Note that we do not convert OBJECT to the BASELINK_BINFO
2487 base. That will happen when the function is called. */
2488 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
2489 }
2490 else if (TREE_CODE (member) == CONST_DECL)
2491 {
2492 /* The member is an enumerator. */
2493 result = member;
2494 /* If OBJECT has side-effects, they are supposed to occur. */
2495 if (TREE_SIDE_EFFECTS (object))
2496 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2497 object, result);
2498 }
2499 else if ((using_decl = strip_using_decl (member)) != member)
2500 result = build_class_member_access_expr (object,
2501 using_decl,
2502 access_path, preserve_reference,
2503 complain);
2504 else
2505 {
2506 if (complain & tf_error)
2507 error ("invalid use of %qD", member);
2508 return error_mark_node;
2509 }
2510
2511 if (!preserve_reference)
2512 /* [expr.ref]
2513
2514 If E2 is declared to have type "reference to T", then ... the
2515 type of E1.E2 is T. */
2516 result = convert_from_reference (result);
2517
2518 return result;
2519}
2520
2521/* Return the destructor denoted by OBJECT.SCOPE::DTOR_NAME, or, if
2522 SCOPE is NULL, by OBJECT.DTOR_NAME, where DTOR_NAME is ~type. */
2523
2524static tree
2525lookup_destructor (tree object, tree scope, tree dtor_name,
2526 tsubst_flags_t complain)
2527{
2528 tree object_type = TREE_TYPE (object);
2529 tree dtor_type = TREE_OPERAND (dtor_name, 0);
2530 tree expr;
2531
2532 /* We've already complained about this destructor. */
2533 if (dtor_type == error_mark_node)
2534 return error_mark_node;
2535
2536 if (scope && !check_dtor_name (scope, dtor_type))
2537 {
2538 if (complain & tf_error)
2539 error ("qualified type %qT does not match destructor name ~%qT",
2540 scope, dtor_type);
2541 return error_mark_node;
2542 }
2543 if (is_auto (dtor_type))
2544 dtor_type = object_type;
2545 else if (identifier_p (dtor_type))
2546 {
2547 /* In a template, names we can't find a match for are still accepted
2548 destructor names, and we check them here. */
2549 if (check_dtor_name (object_type, dtor_type))
2550 dtor_type = object_type;
2551 else
2552 {
2553 if (complain & tf_error)
2554 error ("object type %qT does not match destructor name ~%qT",
2555 object_type, dtor_type);
2556 return error_mark_node;
2557 }
2558
2559 }
2560 else if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
2561 {
2562 if (complain & tf_error)
2563 error ("the type being destroyed is %qT, but the destructor "
2564 "refers to %qT", TYPE_MAIN_VARIANT (object_type), dtor_type);
2565 return error_mark_node;
2566 }
2567 expr = lookup_member (dtor_type, complete_dtor_identifier,
2568 /*protect=*/1, /*want_type=*/false,
2569 tf_warning_or_error);
2570 if (!expr)
2571 {
2572 if (complain & tf_error)
2573 cxx_incomplete_type_error (dtor_name, dtor_type);
2574 return error_mark_node;
2575 }
2576 expr = (adjust_result_of_qualified_name_lookup
2577 (expr, dtor_type, object_type));
2578 if (scope == NULL_TREE)
2579 /* We need to call adjust_result_of_qualified_name_lookup in case the
2580 destructor names a base class, but we unset BASELINK_QUALIFIED_P so
2581 that we still get virtual function binding. */
2582 BASELINK_QUALIFIED_P (expr) = false;
2583 return expr;
2584}
2585
2586/* An expression of the form "A::template B" has been resolved to
2587 DECL. Issue a diagnostic if B is not a template or template
2588 specialization. */
2589
2590void
2591check_template_keyword (tree decl)
2592{
2593 /* The standard says:
2594
2595 [temp.names]
2596
2597 If a name prefixed by the keyword template is not a member
2598 template, the program is ill-formed.
2599
2600 DR 228 removed the restriction that the template be a member
2601 template.
2602
2603 DR 96, if accepted would add the further restriction that explicit
2604 template arguments must be provided if the template keyword is
2605 used, but, as of 2005-10-16, that DR is still in "drafting". If
2606 this DR is accepted, then the semantic checks here can be
2607 simplified, as the entity named must in fact be a template
2608 specialization, rather than, as at present, a set of overloaded
2609 functions containing at least one template function. */
2610 if (TREE_CODE (decl) != TEMPLATE_DECL
2611 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
2612 {
2613 if (VAR_P (decl))
2614 {
2615 if (DECL_USE_TEMPLATE (decl)
2616 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (decl)))
2617 ;
2618 else
2619 permerror (input_location, "%qD is not a template", decl);
2620 }
2621 else if (!is_overloaded_fn (decl))
2622 permerror (input_location, "%qD is not a template", decl);
2623 else
2624 {
2625 bool found = false;
2626
2627 for (lkp_iterator iter (MAYBE_BASELINK_FUNCTIONS (decl));
2628 !found && iter; ++iter)
2629 {
2630 tree fn = *iter;
2631 if (TREE_CODE (fn) == TEMPLATE_DECL
2632 || TREE_CODE (fn) == TEMPLATE_ID_EXPR
2633 || (TREE_CODE (fn) == FUNCTION_DECL
2634 && DECL_USE_TEMPLATE (fn)
2635 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn))))
2636 found = true;
2637 }
2638 if (!found)
2639 permerror (input_location, "%qD is not a template", decl);
2640 }
2641 }
2642}
2643
2644/* Record that an access failure occurred on BASETYPE_PATH attempting
2645 to access FIELD_DECL. */
2646
2647void
2648access_failure_info::record_access_failure (tree basetype_path,
2649 tree field_decl)
2650{
2651 m_was_inaccessible = true;
2652 m_basetype_path = basetype_path;
2653 m_field_decl = field_decl;
2654}
2655
2656/* If an access failure was recorded, then attempt to locate an
2657 accessor function for the pertinent field, and if one is
2658 available, add a note and fix-it hint suggesting using it. */
2659
2660void
2661access_failure_info::maybe_suggest_accessor (bool const_p) const
2662{
2663 if (!m_was_inaccessible)
2664 return;
2665
2666 tree accessor
2667 = locate_field_accessor (m_basetype_path, m_field_decl, const_p);
2668 if (!accessor)
2669 return;
2670
2671 /* The accessor must itself be accessible for it to be a reasonable
2672 suggestion. */
2673 if (!accessible_p (m_basetype_path, accessor, true))
2674 return;
2675
2676 rich_location richloc (line_table, input_location);
2677 pretty_printer pp;
2678 pp_printf (&pp, "%s()", IDENTIFIER_POINTER (DECL_NAME (accessor)));
2679 richloc.add_fixit_replace (pp_formatted_text (&pp));
2680 inform (&richloc, "field %q#D can be accessed via %q#D",
2681 m_field_decl, accessor);
2682}
2683
2684/* This function is called by the parser to process a class member
2685 access expression of the form OBJECT.NAME. NAME is a node used by
2686 the parser to represent a name; it is not yet a DECL. It may,
2687 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2688 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2689 there is no reason to do the lookup twice, so the parser keeps the
2690 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2691 be a template via the use of the "A::template B" syntax. */
2692
2693tree
2694finish_class_member_access_expr (cp_expr object, tree name, bool template_p,
2695 tsubst_flags_t complain)
2696{
2697 tree expr;
2698 tree object_type;
2699 tree member;
2700 tree access_path = NULL_TREE;
2701 tree orig_object = object;
2702 tree orig_name = name;
2703
2704 if (object == error_mark_node || name == error_mark_node)
2705 return error_mark_node;
2706
2707 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2708 if (!objc_is_public (object, name))
2709 return error_mark_node;
2710
2711 object_type = TREE_TYPE (object);
2712
2713 if (processing_template_decl)
2714 {
2715 if (/* If OBJECT is dependent, so is OBJECT.NAME. */
2716 type_dependent_object_expression_p (object)
2717 /* If NAME is "f<args>", where either 'f' or 'args' is
2718 dependent, then the expression is dependent. */
2719 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2720 && dependent_template_id_p (TREE_OPERAND (name, 0),
2721 TREE_OPERAND (name, 1)))
2722 /* If NAME is "T::X" where "T" is dependent, then the
2723 expression is dependent. */
2724 || (TREE_CODE (name) == SCOPE_REF
2725 && TYPE_P (TREE_OPERAND (name, 0))
2726 && dependent_scope_p (TREE_OPERAND (name, 0))))
2727 {
2728 dependent:
2729 return build_min_nt_loc (UNKNOWN_LOCATION, COMPONENT_REF,
2730 orig_object, orig_name, NULL_TREE);
2731 }
2732 object = build_non_dependent_expr (object);
2733 }
2734 else if (c_dialect_objc ()
2735 && identifier_p (name)
2736 && (expr = objc_maybe_build_component_ref (object, name)))
2737 return expr;
2738
2739 /* [expr.ref]
2740
2741 The type of the first expression shall be "class object" (of a
2742 complete type). */
2743 if (!currently_open_class (object_type)
2744 && !complete_type_or_maybe_complain (object_type, object, complain))
2745 return error_mark_node;
2746 if (!CLASS_TYPE_P (object_type))
2747 {
2748 if (complain & tf_error)
2749 {
2750 if (POINTER_TYPE_P (object_type)
2751 && CLASS_TYPE_P (TREE_TYPE (object_type)))
2752 error ("request for member %qD in %qE, which is of pointer "
2753 "type %qT (maybe you meant to use %<->%> ?)",
2754 name, object.get_value (), object_type);
2755 else
2756 error ("request for member %qD in %qE, which is of non-class "
2757 "type %qT", name, object.get_value (), object_type);
2758 }
2759 return error_mark_node;
2760 }
2761
2762 if (BASELINK_P (name))
2763 /* A member function that has already been looked up. */
2764 member = name;
2765 else
2766 {
2767 bool is_template_id = false;
2768 tree template_args = NULL_TREE;
2769 tree scope = NULL_TREE;
2770
2771 access_path = object_type;
2772
2773 if (TREE_CODE (name) == SCOPE_REF)
2774 {
2775 /* A qualified name. The qualifying class or namespace `S'
2776 has already been looked up; it is either a TYPE or a
2777 NAMESPACE_DECL. */
2778 scope = TREE_OPERAND (name, 0);
2779 name = TREE_OPERAND (name, 1);
2780
2781 /* If SCOPE is a namespace, then the qualified name does not
2782 name a member of OBJECT_TYPE. */
2783 if (TREE_CODE (scope) == NAMESPACE_DECL)
2784 {
2785 if (complain & tf_error)
2786 error ("%<%D::%D%> is not a member of %qT",
2787 scope, name, object_type);
2788 return error_mark_node;
2789 }
2790 }
2791
2792 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2793 {
2794 is_template_id = true;
2795 template_args = TREE_OPERAND (name, 1);
2796 name = TREE_OPERAND (name, 0);
2797
2798 if (!identifier_p (name))
2799 name = OVL_NAME (name);
2800 }
2801
2802 if (scope)
2803 {
2804 if (TREE_CODE (scope) == ENUMERAL_TYPE)
2805 {
2806 gcc_assert (!is_template_id);
2807 /* Looking up a member enumerator (c++/56793). */
2808 if (!TYPE_CLASS_SCOPE_P (scope)
2809 || !DERIVED_FROM_P (TYPE_CONTEXT (scope), object_type))
2810 {
2811 if (complain & tf_error)
2812 error ("%<%D::%D%> is not a member of %qT",
2813 scope, name, object_type);
2814 return error_mark_node;
2815 }
2816 tree val = lookup_enumerator (scope, name);
2817 if (!val)
2818 {
2819 if (complain & tf_error)
2820 error ("%qD is not a member of %qD",
2821 name, scope);
2822 return error_mark_node;
2823 }
2824
2825 if (TREE_SIDE_EFFECTS (object))
2826 val = build2 (COMPOUND_EXPR, TREE_TYPE (val), object, val);
2827 return val;
2828 }
2829
2830 gcc_assert (CLASS_TYPE_P (scope));
2831 gcc_assert (identifier_p (name) || TREE_CODE (name) == BIT_NOT_EXPR);
2832
2833 if (constructor_name_p (name, scope))
2834 {
2835 if (complain & tf_error)
2836 error ("cannot call constructor %<%T::%D%> directly",
2837 scope, name);
2838 return error_mark_node;
2839 }
2840
2841 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2842 access_path = lookup_base (object_type, scope, ba_check,
2843 NULL, complain);
2844 if (access_path == error_mark_node)
2845 return error_mark_node;
2846 if (!access_path)
2847 {
2848 if (any_dependent_bases_p (object_type))
2849 goto dependent;
2850 if (complain & tf_error)
2851 error ("%qT is not a base of %qT", scope, object_type);
2852 return error_mark_node;
2853 }
2854 }
2855
2856 if (TREE_CODE (name) == BIT_NOT_EXPR)
2857 {
2858 if (dependent_type_p (object_type))
2859 /* The destructor isn't declared yet. */
2860 goto dependent;
2861 member = lookup_destructor (object, scope, name, complain);
2862 }
2863 else
2864 {
2865 /* Look up the member. */
2866 access_failure_info afi;
2867 member = lookup_member (access_path, name, /*protect=*/1,
2868 /*want_type=*/false, complain,
2869 &afi);
2870 afi.maybe_suggest_accessor (TYPE_READONLY (object_type));
2871 if (member == NULL_TREE)
2872 {
2873 if (dependent_type_p (object_type))
2874 /* Try again at instantiation time. */
2875 goto dependent;
2876 if (complain & tf_error)
2877 {
2878 tree guessed_id = lookup_member_fuzzy (access_path, name,
2879 /*want_type=*/false);
2880 if (guessed_id)
2881 {
2882 location_t bogus_component_loc = input_location;
2883 gcc_rich_location rich_loc (bogus_component_loc);
2884 rich_loc.add_fixit_misspelled_id (bogus_component_loc,
2885 guessed_id);
2886 error_at (&rich_loc,
2887 "%q#T has no member named %qE;"
2888 " did you mean %qE?",
2889 TREE_CODE (access_path) == TREE_BINFO
2890 ? TREE_TYPE (access_path) : object_type,
2891 name, guessed_id);
2892 }
2893 else
2894 error ("%q#T has no member named %qE",
2895 TREE_CODE (access_path) == TREE_BINFO
2896 ? TREE_TYPE (access_path) : object_type, name);
2897 }
2898 return error_mark_node;
2899 }
2900 if (member == error_mark_node)
2901 return error_mark_node;
2902 if (DECL_P (member)
2903 && any_dependent_type_attributes_p (DECL_ATTRIBUTES (member)))
2904 /* Dependent type attributes on the decl mean that the TREE_TYPE is
2905 wrong, so don't use it. */
2906 goto dependent;
2907 if (TREE_CODE (member) == USING_DECL && DECL_DEPENDENT_P (member))
2908 goto dependent;
2909 }
2910
2911 if (is_template_id)
2912 {
2913 tree templ = member;
2914
2915 if (BASELINK_P (templ))
2916 member = lookup_template_function (templ, template_args);
2917 else if (variable_template_p (templ))
2918 member = (lookup_and_finish_template_variable
2919 (templ, template_args, complain));
2920 else
2921 {
2922 if (complain & tf_error)
2923 error ("%qD is not a member template function", name);
2924 return error_mark_node;
2925 }
2926 }
2927 }
2928
2929 if (TREE_DEPRECATED (member))
2930 warn_deprecated_use (member, NULL_TREE);
2931
2932 if (template_p)
2933 check_template_keyword (member);
2934
2935 expr = build_class_member_access_expr (object, member, access_path,
2936 /*preserve_reference=*/false,
2937 complain);
2938 if (processing_template_decl && expr != error_mark_node)
2939 {
2940 if (BASELINK_P (member))
2941 {
2942 if (TREE_CODE (orig_name) == SCOPE_REF)
2943 BASELINK_QUALIFIED_P (member) = 1;
2944 orig_name = member;
2945 }
2946 return build_min_non_dep (COMPONENT_REF, expr,
2947 orig_object, orig_name,
2948 NULL_TREE);
2949 }
2950
2951 return expr;
2952}
2953
2954/* Build a COMPONENT_REF of OBJECT and MEMBER with the appropriate
2955 type. */
2956
2957tree
2958build_simple_component_ref (tree object, tree member)
2959{
2960 tree type = cp_build_qualified_type (TREE_TYPE (member),
2961 cp_type_quals (TREE_TYPE (object)));
2962 return build3_loc (input_location,
2963 COMPONENT_REF, type,
2964 object, member, NULL_TREE);
2965}
2966
2967/* Return an expression for the MEMBER_NAME field in the internal
2968 representation of PTRMEM, a pointer-to-member function. (Each
2969 pointer-to-member function type gets its own RECORD_TYPE so it is
2970 more convenient to access the fields by name than by FIELD_DECL.)
2971 This routine converts the NAME to a FIELD_DECL and then creates the
2972 node for the complete expression. */
2973
2974tree
2975build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2976{
2977 tree ptrmem_type;
2978 tree member;
2979
2980 /* This code is a stripped down version of
2981 build_class_member_access_expr. It does not work to use that
2982 routine directly because it expects the object to be of class
2983 type. */
2984 ptrmem_type = TREE_TYPE (ptrmem);
2985 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2986 for (member = TYPE_FIELDS (ptrmem_type); member;
2987 member = DECL_CHAIN (member))
2988 if (DECL_NAME (member) == member_name)
2989 break;
2990 tree res = build_simple_component_ref (ptrmem, member);
2991
2992 TREE_NO_WARNING (res) = 1;
2993 return res;
2994}
2995
2996/* Given an expression PTR for a pointer, return an expression
2997 for the value pointed to.
2998 ERRORSTRING is the name of the operator to appear in error messages.
2999
3000 This function may need to overload OPERATOR_FNNAME.
3001 Must also handle REFERENCE_TYPEs for C++. */
3002
3003tree
3004build_x_indirect_ref (location_t loc, tree expr, ref_operator errorstring,
3005 tsubst_flags_t complain)
3006{
3007 tree orig_expr = expr;
3008 tree rval;
3009 tree overload = NULL_TREE;
3010
3011 if (processing_template_decl)
3012 {
3013 /* Retain the type if we know the operand is a pointer. */
3014 if (TREE_TYPE (expr) && POINTER_TYPE_P (TREE_TYPE (expr)))
3015 return build_min (INDIRECT_REF, TREE_TYPE (TREE_TYPE (expr)), expr);
3016 if (type_dependent_expression_p (expr))
3017 return build_min_nt_loc (loc, INDIRECT_REF, expr);
3018 expr = build_non_dependent_expr (expr);
3019 }
3020
3021 rval = build_new_op (loc, INDIRECT_REF, LOOKUP_NORMAL, expr,
3022 NULL_TREE, NULL_TREE, &overload, complain);
3023 if (!rval)
3024 rval = cp_build_indirect_ref (expr, errorstring, complain);
3025
3026 if (processing_template_decl && rval != error_mark_node)
3027 {
3028 if (overload != NULL_TREE)
3029 return (build_min_non_dep_op_overload
3030 (INDIRECT_REF, rval, overload, orig_expr));
3031
3032 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
3033 }
3034 else
3035 return rval;
3036}
3037
3038/* The implementation of the above, and of indirection implied by other
3039 constructs. If DO_FOLD is true, fold away INDIRECT_REF of ADDR_EXPR. */
3040
3041static tree
3042cp_build_indirect_ref_1 (tree ptr, ref_operator errorstring,
3043 tsubst_flags_t complain, bool do_fold)
3044{
3045 tree pointer, type;
3046
3047 /* RO_NULL should only be used with the folding entry points below, not
3048 cp_build_indirect_ref. */
3049 gcc_checking_assert (errorstring != RO_NULL || do_fold);
3050
3051 if (ptr == current_class_ptr
3052 || (TREE_CODE (ptr) == NOP_EXPR
3053 && TREE_OPERAND (ptr, 0) == current_class_ptr
3054 && (same_type_ignoring_top_level_qualifiers_p
3055 (TREE_TYPE (ptr), TREE_TYPE (current_class_ptr)))))
3056 return current_class_ref;
3057
3058 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
3059 ? ptr : decay_conversion (ptr, complain));
3060 if (pointer == error_mark_node)
3061 return error_mark_node;
3062
3063 type = TREE_TYPE (pointer);
3064
3065 if (POINTER_TYPE_P (type))
3066 {
3067 /* [expr.unary.op]
3068
3069 If the type of the expression is "pointer to T," the type
3070 of the result is "T." */
3071 tree t = TREE_TYPE (type);
3072
3073 if ((CONVERT_EXPR_P (ptr)
3074 || TREE_CODE (ptr) == VIEW_CONVERT_EXPR)
3075 && (!CLASS_TYPE_P (t) || !CLASSTYPE_EMPTY_P (t)))
3076 {
3077 /* If a warning is issued, mark it to avoid duplicates from
3078 the backend. This only needs to be done at
3079 warn_strict_aliasing > 2. */
3080 if (warn_strict_aliasing > 2)
3081 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (ptr, 0)),
3082 type, TREE_OPERAND (ptr, 0)))
3083 TREE_NO_WARNING (ptr) = 1;
3084 }
3085
3086 if (VOID_TYPE_P (t))
3087 {
3088 /* A pointer to incomplete type (other than cv void) can be
3089 dereferenced [expr.unary.op]/1 */
3090 if (complain & tf_error)
3091 error ("%qT is not a pointer-to-object type", type);
3092 return error_mark_node;
3093 }
3094 else if (do_fold && TREE_CODE (pointer) == ADDR_EXPR
3095 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
3096 /* The POINTER was something like `&x'. We simplify `*&x' to
3097 `x'. */
3098 return TREE_OPERAND (pointer, 0);
3099 else
3100 {
3101 tree ref = build1 (INDIRECT_REF, t, pointer);
3102
3103 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
3104 so that we get the proper error message if the result is used
3105 to assign to. Also, &* is supposed to be a no-op. */
3106 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
3107 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
3108 TREE_SIDE_EFFECTS (ref)
3109 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
3110 return ref;
3111 }
3112 }
3113 else if (!(complain & tf_error))
3114 /* Don't emit any errors; we'll just return ERROR_MARK_NODE later. */
3115 ;
3116 /* `pointer' won't be an error_mark_node if we were given a
3117 pointer to member, so it's cool to check for this here. */
3118 else if (TYPE_PTRMEM_P (type))
3119 switch (errorstring)
3120 {
3121 case RO_ARRAY_INDEXING:
3122 error ("invalid use of array indexing on pointer to member");
3123 break;
3124 case RO_UNARY_STAR:
3125 error ("invalid use of unary %<*%> on pointer to member");
3126 break;
3127 case RO_IMPLICIT_CONVERSION:
3128 error ("invalid use of implicit conversion on pointer to member");
3129 break;
3130 case RO_ARROW_STAR:
3131 error ("left hand operand of %<->*%> must be a pointer to class, "
3132 "but is a pointer to member of type %qT", type);
3133 break;
3134 default:
3135 gcc_unreachable ();
3136 }
3137 else if (pointer != error_mark_node)
3138 invalid_indirection_error (input_location, type, errorstring);
3139
3140 return error_mark_node;
3141}
3142
3143/* Entry point used by c-common, which expects folding. */
3144
3145tree
3146build_indirect_ref (location_t /*loc*/,
3147 tree ptr, ref_operator errorstring)
3148{
3149 return cp_build_indirect_ref_1 (ptr, errorstring, tf_warning_or_error, true);
3150}
3151
3152/* Entry point used by internal indirection needs that don't correspond to any
3153 syntactic construct. */
3154
3155tree
3156cp_build_fold_indirect_ref (tree pointer)
3157{
3158 return cp_build_indirect_ref_1 (pointer, RO_NULL, tf_warning_or_error, true);
3159}
3160
3161/* Entry point used by indirection needs that correspond to some syntactic
3162 construct. */
3163
3164tree
3165cp_build_indirect_ref (tree ptr, ref_operator errorstring,
3166 tsubst_flags_t complain)
3167{
3168 return cp_build_indirect_ref_1 (ptr, errorstring, complain, false);
3169}
3170
3171/* This handles expressions of the form "a[i]", which denotes
3172 an array reference.
3173
3174 This is logically equivalent in C to *(a+i), but we may do it differently.
3175 If A is a variable or a member, we generate a primitive ARRAY_REF.
3176 This avoids forcing the array out of registers, and can work on
3177 arrays that are not lvalues (for example, members of structures returned
3178 by functions).
3179
3180 If INDEX is of some user-defined type, it must be converted to
3181 integer type. Otherwise, to make a compatible PLUS_EXPR, it
3182 will inherit the type of the array, which will be some pointer type.
3183
3184 LOC is the location to use in building the array reference. */
3185
3186tree
3187cp_build_array_ref (location_t loc, tree array, tree idx,
3188 tsubst_flags_t complain)
3189{
3190 tree ret;
3191
3192 if (idx == 0)
3193 {
3194 if (complain & tf_error)
3195 error_at (loc, "subscript missing in array reference");
3196 return error_mark_node;
3197 }
3198
3199 if (TREE_TYPE (array) == error_mark_node
3200 || TREE_TYPE (idx) == error_mark_node)
3201 return error_mark_node;
3202
3203 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
3204 inside it. */
3205 switch (TREE_CODE (array))
3206 {
3207 case COMPOUND_EXPR:
3208 {
3209 tree value = cp_build_array_ref (loc, TREE_OPERAND (array, 1), idx,
3210 complain);
3211 ret = build2 (COMPOUND_EXPR, TREE_TYPE (value),
3212 TREE_OPERAND (array, 0), value);
3213 SET_EXPR_LOCATION (ret, loc);
3214 return ret;
3215 }
3216
3217 case COND_EXPR:
3218 ret = build_conditional_expr
3219 (loc, TREE_OPERAND (array, 0),
3220 cp_build_array_ref (loc, TREE_OPERAND (array, 1), idx,
3221 complain),
3222 cp_build_array_ref (loc, TREE_OPERAND (array, 2), idx,
3223 complain),
3224 complain);
3225 protected_set_expr_location (ret, loc);
3226 return ret;
3227
3228 default:
3229 break;
3230 }
3231
3232 bool non_lvalue = convert_vector_to_array_for_subscript (loc, &array, idx);
3233
3234 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
3235 {
3236 tree rval, type;
3237
3238 warn_array_subscript_with_type_char (loc, idx);
3239
3240 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
3241 {
3242 if (complain & tf_error)
3243 error_at (loc, "array subscript is not an integer");
3244 return error_mark_node;
3245 }
3246
3247 /* Apply integral promotions *after* noticing character types.
3248 (It is unclear why we do these promotions -- the standard
3249 does not say that we should. In fact, the natural thing would
3250 seem to be to convert IDX to ptrdiff_t; we're performing
3251 pointer arithmetic.) */
3252 idx = cp_perform_integral_promotions (idx, complain);
3253
3254 /* An array that is indexed by a non-constant
3255 cannot be stored in a register; we must be able to do
3256 address arithmetic on its address.
3257 Likewise an array of elements of variable size. */
3258 if (TREE_CODE (idx) != INTEGER_CST
3259 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
3260 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
3261 != INTEGER_CST)))
3262 {
3263 if (!cxx_mark_addressable (array, true))
3264 return error_mark_node;
3265 }
3266
3267 /* An array that is indexed by a constant value which is not within
3268 the array bounds cannot be stored in a register either; because we
3269 would get a crash in store_bit_field/extract_bit_field when trying
3270 to access a non-existent part of the register. */
3271 if (TREE_CODE (idx) == INTEGER_CST
3272 && TYPE_DOMAIN (TREE_TYPE (array))
3273 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
3274 {
3275 if (!cxx_mark_addressable (array))
3276 return error_mark_node;
3277 }
3278
3279 /* Note in C++ it is valid to subscript a `register' array, since
3280 it is valid to take the address of something with that
3281 storage specification. */
3282 if (extra_warnings)
3283 {
3284 tree foo = array;
3285 while (TREE_CODE (foo) == COMPONENT_REF)
3286 foo = TREE_OPERAND (foo, 0);
3287 if (VAR_P (foo) && DECL_REGISTER (foo)
3288 && (complain & tf_warning))
3289 warning_at (loc, OPT_Wextra,
3290 "subscripting array declared %<register%>");
3291 }
3292
3293 type = TREE_TYPE (TREE_TYPE (array));
3294 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
3295 /* Array ref is const/volatile if the array elements are
3296 or if the array is.. */
3297 TREE_READONLY (rval)
3298 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
3299 TREE_SIDE_EFFECTS (rval)
3300 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
3301 TREE_THIS_VOLATILE (rval)
3302 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
3303 ret = require_complete_type_sfinae (rval, complain);
3304 protected_set_expr_location (ret, loc);
3305 if (non_lvalue)
3306 ret = non_lvalue_loc (loc, ret);
3307 return ret;
3308 }
3309
3310 {
3311 tree ar = cp_default_conversion (array, complain);
3312 tree ind = cp_default_conversion (idx, complain);
3313
3314 /* Put the integer in IND to simplify error checking. */
3315 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
3316 std::swap (ar, ind);
3317
3318 if (ar == error_mark_node || ind == error_mark_node)
3319 return error_mark_node;
3320
3321 if (!TYPE_PTR_P (TREE_TYPE (ar)))
3322 {
3323 if (complain & tf_error)
3324 error_at (loc, "subscripted value is neither array nor pointer");
3325 return error_mark_node;
3326 }
3327 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
3328 {
3329 if (complain & tf_error)
3330 error_at (loc, "array subscript is not an integer");
3331 return error_mark_node;
3332 }
3333
3334 warn_array_subscript_with_type_char (loc, idx);
3335
3336 ret = cp_build_indirect_ref (cp_build_binary_op (input_location,
3337 PLUS_EXPR, ar, ind,
3338 complain),
3339 RO_ARRAY_INDEXING,
3340 complain);
3341 protected_set_expr_location (ret, loc);
3342 if (non_lvalue)
3343 ret = non_lvalue_loc (loc, ret);
3344 return ret;
3345 }
3346}
3347
3348/* Entry point for Obj-C++. */
3349
3350tree
3351build_array_ref (location_t loc, tree array, tree idx)
3352{
3353 return cp_build_array_ref (loc, array, idx, tf_warning_or_error);
3354}
3355
3356/* Resolve a pointer to member function. INSTANCE is the object
3357 instance to use, if the member points to a virtual member.
3358
3359 This used to avoid checking for virtual functions if basetype
3360 has no virtual functions, according to an earlier ANSI draft.
3361 With the final ISO C++ rules, such an optimization is
3362 incorrect: A pointer to a derived member can be static_cast
3363 to pointer-to-base-member, as long as the dynamic object
3364 later has the right member. So now we only do this optimization
3365 when we know the dynamic type of the object. */
3366
3367tree
3368get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function,
3369 tsubst_flags_t complain)
3370{
3371 if (TREE_CODE (function) == OFFSET_REF)
3372 function = TREE_OPERAND (function, 1);
3373
3374 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
3375 {
3376 tree idx, delta, e1, e2, e3, vtbl;
3377 bool nonvirtual;
3378 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
3379 tree basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
3380
3381 tree instance_ptr = *instance_ptrptr;
3382 tree instance_save_expr = 0;
3383 if (instance_ptr == error_mark_node)
3384 {
3385 if (TREE_CODE (function) == PTRMEM_CST)
3386 {
3387 /* Extracting the function address from a pmf is only
3388 allowed with -Wno-pmf-conversions. It only works for
3389 pmf constants. */
3390 e1 = build_addr_func (PTRMEM_CST_MEMBER (function), complain);
3391 e1 = convert (fntype, e1);
3392 return e1;
3393 }
3394 else
3395 {
3396 if (complain & tf_error)
3397 error ("object missing in use of %qE", function);
3398 return error_mark_node;
3399 }
3400 }
3401
3402 /* True if we know that the dynamic type of the object doesn't have
3403 virtual functions, so we can assume the PFN field is a pointer. */
3404 nonvirtual = (COMPLETE_TYPE_P (basetype)
3405 && !TYPE_POLYMORPHIC_P (basetype)
3406 && resolves_to_fixed_type_p (instance_ptr, 0));
3407
3408 /* If we don't really have an object (i.e. in an ill-formed
3409 conversion from PMF to pointer), we can't resolve virtual
3410 functions anyway. */
3411 if (!nonvirtual && is_dummy_object (instance_ptr))
3412 nonvirtual = true;
3413
3414 if (TREE_SIDE_EFFECTS (instance_ptr))
3415 instance_ptr = instance_save_expr = save_expr (instance_ptr);
3416
3417 if (TREE_SIDE_EFFECTS (function))
3418 function = save_expr (function);
3419
3420 /* Start by extracting all the information from the PMF itself. */
3421 e3 = pfn_from_ptrmemfunc (function);
3422 delta = delta_from_ptrmemfunc (function);
3423 idx = build1 (NOP_EXPR, vtable_index_type, e3);
3424 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
3425 {
3426 int flag_sanitize_save;
3427 case ptrmemfunc_vbit_in_pfn:
3428 e1 = cp_build_binary_op (input_location,
3429 BIT_AND_EXPR, idx, integer_one_node,
3430 complain);
3431 idx = cp_build_binary_op (input_location,
3432 MINUS_EXPR, idx, integer_one_node,
3433 complain);
3434 if (idx == error_mark_node)
3435 return error_mark_node;
3436 break;
3437
3438 case ptrmemfunc_vbit_in_delta:
3439 e1 = cp_build_binary_op (input_location,
3440 BIT_AND_EXPR, delta, integer_one_node,
3441 complain);
3442 /* Don't instrument the RSHIFT_EXPR we're about to create because
3443 we're going to use DELTA number of times, and that wouldn't play
3444 well with SAVE_EXPRs therein. */
3445 flag_sanitize_save = flag_sanitize;
3446 flag_sanitize = 0;
3447 delta = cp_build_binary_op (input_location,
3448 RSHIFT_EXPR, delta, integer_one_node,
3449 complain);
3450 flag_sanitize = flag_sanitize_save;
3451 if (delta == error_mark_node)
3452 return error_mark_node;
3453 break;
3454
3455 default:
3456 gcc_unreachable ();
3457 }
3458
3459 if (e1 == error_mark_node)
3460 return error_mark_node;
3461
3462 /* Convert down to the right base before using the instance. A
3463 special case is that in a pointer to member of class C, C may
3464 be incomplete. In that case, the function will of course be
3465 a member of C, and no conversion is required. In fact,
3466 lookup_base will fail in that case, because incomplete
3467 classes do not have BINFOs. */
3468 if (!same_type_ignoring_top_level_qualifiers_p
3469 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
3470 {
3471 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
3472 basetype, ba_check, NULL, complain);
3473 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
3474 1, complain);
3475 if (instance_ptr == error_mark_node)
3476 return error_mark_node;
3477 }
3478 /* ...and then the delta in the PMF. */
3479 instance_ptr = fold_build_pointer_plus (instance_ptr, delta);
3480
3481 /* Hand back the adjusted 'this' argument to our caller. */
3482 *instance_ptrptr = instance_ptr;
3483
3484 if (nonvirtual)
3485 /* Now just return the pointer. */
3486 return e3;
3487
3488 /* Next extract the vtable pointer from the object. */
3489 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
3490 instance_ptr);
3491 vtbl = cp_build_fold_indirect_ref (vtbl);
3492 if (vtbl == error_mark_node)
3493 return error_mark_node;
3494
3495 /* Finally, extract the function pointer from the vtable. */
3496 e2 = fold_build_pointer_plus_loc (input_location, vtbl, idx);
3497 e2 = cp_build_fold_indirect_ref (e2);
3498 if (e2 == error_mark_node)
3499 return error_mark_node;
3500 TREE_CONSTANT (e2) = 1;
3501
3502 /* When using function descriptors, the address of the
3503 vtable entry is treated as a function pointer. */
3504 if (TARGET_VTABLE_USES_DESCRIPTORS)
3505 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
3506 cp_build_addr_expr (e2, complain));
3507
3508 e2 = fold_convert (TREE_TYPE (e3), e2);
3509 e1 = build_conditional_expr (input_location, e1, e2, e3, complain);
3510 if (e1 == error_mark_node)
3511 return error_mark_node;
3512
3513 /* Make sure this doesn't get evaluated first inside one of the
3514 branches of the COND_EXPR. */
3515 if (instance_save_expr)
3516 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
3517 instance_save_expr, e1);
3518
3519 function = e1;
3520 }
3521 return function;
3522}
3523
3524/* Used by the C-common bits. */
3525tree
3526build_function_call (location_t /*loc*/,
3527 tree function, tree params)
3528{
3529 return cp_build_function_call (function, params, tf_warning_or_error);
3530}
3531
3532/* Used by the C-common bits. */
3533tree
3534build_function_call_vec (location_t /*loc*/, vec<location_t> /*arg_loc*/,
3535 tree function, vec<tree, va_gc> *params,
3536 vec<tree, va_gc> * /*origtypes*/)
3537{
3538 vec<tree, va_gc> *orig_params = params;
3539 tree ret = cp_build_function_call_vec (function, &params,
3540 tf_warning_or_error);
3541
3542 /* cp_build_function_call_vec can reallocate PARAMS by adding
3543 default arguments. That should never happen here. Verify
3544 that. */
3545 gcc_assert (params == orig_params);
3546
3547 return ret;
3548}
3549
3550/* Build a function call using a tree list of arguments. */
3551
3552static tree
3553cp_build_function_call (tree function, tree params, tsubst_flags_t complain)
3554{
3555 vec<tree, va_gc> *vec;
3556 tree ret;
3557
3558 vec = make_tree_vector ();
3559 for (; params != NULL_TREE; params = TREE_CHAIN (params))
3560 vec_safe_push (vec, TREE_VALUE (params));
3561 ret = cp_build_function_call_vec (function, &vec, complain);
3562 release_tree_vector (vec);
3563 return ret;
3564}
3565
3566/* Build a function call using varargs. */
3567
3568tree
3569cp_build_function_call_nary (tree function, tsubst_flags_t complain, ...)
3570{
3571 vec<tree, va_gc> *vec;
3572 va_list args;
3573 tree ret, t;
3574
3575 vec = make_tree_vector ();
3576 va_start (args, complain);
3577 for (t = va_arg (args, tree); t != NULL_TREE; t = va_arg (args, tree))
3578 vec_safe_push (vec, t);
3579 va_end (args);
3580 ret = cp_build_function_call_vec (function, &vec, complain);
3581 release_tree_vector (vec);
3582 return ret;
3583}
3584
3585/* Build a function call using a vector of arguments. PARAMS may be
3586 NULL if there are no parameters. This changes the contents of
3587 PARAMS. */
3588
3589tree
3590cp_build_function_call_vec (tree function, vec<tree, va_gc> **params,
3591 tsubst_flags_t complain)
3592{
3593 tree fntype, fndecl;
3594 int is_method;
3595 tree original = function;
3596 int nargs;
3597 tree *argarray;
3598 tree parm_types;
3599 vec<tree, va_gc> *allocated = NULL;
3600 tree ret;
3601
3602 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
3603 expressions, like those used for ObjC messenger dispatches. */
3604 if (params != NULL && !vec_safe_is_empty (*params))
3605 function = objc_rewrite_function_call (function, (**params)[0]);
3606
3607 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3608 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
3609 if (TREE_CODE (function) == NOP_EXPR
3610 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
3611 function = TREE_OPERAND (function, 0);
3612
3613 if (TREE_CODE (function) == FUNCTION_DECL)
3614 {
3615 /* If the function is a non-template member function
3616 or a non-template friend, then we need to check the
3617 constraints.
3618
3619 Note that if overload resolution failed with a single
3620 candidate this function will be used to explicitly diagnose
3621 the failure for the single call expression. The check is
3622 technically redundant since we also would have failed in
3623 add_function_candidate. */
3624 if (flag_concepts
3625 && (complain & tf_error)
3626 && !constraints_satisfied_p (function))
3627 {
3628 error ("cannot call function %qD", function);
3629 location_t loc = DECL_SOURCE_LOCATION (function);
3630 diagnose_constraints (loc, function, NULL_TREE);
3631 return error_mark_node;
3632 }
3633
3634 if (!mark_used (function, complain) && !(complain & tf_error))
3635 return error_mark_node;
3636 fndecl = function;
3637
3638 /* Convert anything with function type to a pointer-to-function. */
3639 if (DECL_MAIN_P (function))
3640 {
3641 if (complain & tf_error)
3642 pedwarn (input_location, OPT_Wpedantic,
3643 "ISO C++ forbids calling %<::main%> from within program");
3644 else
3645 return error_mark_node;
3646 }
3647 function = build_addr_func (function, complain);
3648 }
3649 else
3650 {
3651 fndecl = NULL_TREE;
3652
3653 function = build_addr_func (function, complain);
3654 }
3655
3656 if (function == error_mark_node)
3657 return error_mark_node;
3658
3659 fntype = TREE_TYPE (function);
3660
3661 if (TYPE_PTRMEMFUNC_P (fntype))
3662 {
3663 if (complain & tf_error)
3664 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
3665 "function in %<%E (...)%>, e.g. %<(... ->* %E) (...)%>",
3666 original, original);
3667 return error_mark_node;
3668 }
3669
3670 is_method = (TYPE_PTR_P (fntype)
3671 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
3672
3673 if (!(TYPE_PTRFN_P (fntype)
3674 || is_method
3675 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
3676 {
3677 if (complain & tf_error)
3678 {
3679 if (!flag_diagnostics_show_caret)
3680 error_at (input_location,
3681 "%qE cannot be used as a function", original);
3682 else if (DECL_P (original))
3683 error_at (input_location,
3684 "%qD cannot be used as a function", original);
3685 else
3686 error_at (input_location,
3687 "expression cannot be used as a function");
3688 }
3689
3690 return error_mark_node;
3691 }
3692
3693 /* fntype now gets the type of function pointed to. */
3694 fntype = TREE_TYPE (fntype);
3695 parm_types = TYPE_ARG_TYPES (fntype);
3696
3697 if (params == NULL)
3698 {
3699 allocated = make_tree_vector ();
3700 params = &allocated;
3701 }
3702
3703 nargs = convert_arguments (parm_types, params, fndecl, LOOKUP_NORMAL,
3704 complain);
3705 if (nargs < 0)
3706 return error_mark_node;
3707
3708 argarray = (*params)->address ();
3709
3710 /* Check for errors in format strings and inappropriately
3711 null parameters. */
3712 bool warned_p = check_function_arguments (input_location, fndecl, fntype,
3713 nargs, argarray, NULL);
3714
3715 ret = build_cxx_call (function, nargs, argarray, complain);
3716
3717 if (warned_p)
3718 {
3719 tree c = extract_call_expr (ret);
3720 if (TREE_CODE (c) == CALL_EXPR)
3721 TREE_NO_WARNING (c) = 1;
3722 }
3723
3724 if (allocated != NULL)
3725 release_tree_vector (allocated);
3726
3727 return ret;
3728}
3729
3730/* Subroutine of convert_arguments.
3731 Print an error message about a wrong number of arguments. */
3732
3733static void
3734error_args_num (location_t loc, tree fndecl, bool too_many_p)
3735{
3736 if (fndecl)
3737 {
3738 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
3739 {
3740 if (DECL_NAME (fndecl) == NULL_TREE
3741 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
3742 error_at (loc,
3743 too_many_p
3744 ? G_("too many arguments to constructor %q#D")
3745 : G_("too few arguments to constructor %q#D"),
3746 fndecl);
3747 else
3748 error_at (loc,
3749 too_many_p
3750 ? G_("too many arguments to member function %q#D")
3751 : G_("too few arguments to member function %q#D"),
3752 fndecl);
3753 }
3754 else
3755 error_at (loc,
3756 too_many_p
3757 ? G_("too many arguments to function %q#D")
3758 : G_("too few arguments to function %q#D"),
3759 fndecl);
3760 if (!DECL_IS_BUILTIN (fndecl))
3761 inform (DECL_SOURCE_LOCATION (fndecl), "declared here");
3762 }
3763 else
3764 {
3765 if (c_dialect_objc () && objc_message_selector ())
3766 error_at (loc,
3767 too_many_p
3768 ? G_("too many arguments to method %q#D")
3769 : G_("too few arguments to method %q#D"),
3770 objc_message_selector ());
3771 else
3772 error_at (loc, too_many_p ? G_("too many arguments to function")
3773 : G_("too few arguments to function"));
3774 }
3775}
3776
3777/* Convert the actual parameter expressions in the list VALUES to the
3778 types in the list TYPELIST. The converted expressions are stored
3779 back in the VALUES vector.
3780 If parmdecls is exhausted, or when an element has NULL as its type,
3781 perform the default conversions.
3782
3783 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
3784
3785 This is also where warnings about wrong number of args are generated.
3786
3787 Returns the actual number of arguments processed (which might be less
3788 than the length of the vector), or -1 on error.
3789
3790 In C++, unspecified trailing parameters can be filled in with their
3791 default arguments, if such were specified. Do so here. */
3792
3793static int
3794convert_arguments (tree typelist, vec<tree, va_gc> **values, tree fndecl,
3795 int flags, tsubst_flags_t complain)
3796{
3797 tree typetail;
3798 unsigned int i;
3799
3800 /* Argument passing is always copy-initialization. */
3801 flags |= LOOKUP_ONLYCONVERTING;
3802
3803 for (i = 0, typetail = typelist;
3804 i < vec_safe_length (*values);
3805 i++)
3806 {
3807 tree type = typetail ? TREE_VALUE (typetail) : 0;
3808 tree val = (**values)[i];
3809
3810 if (val == error_mark_node || type == error_mark_node)
3811 return -1;
3812
3813 if (type == void_type_node)
3814 {
3815 if (complain & tf_error)
3816 {
3817 error_args_num (input_location, fndecl, /*too_many_p=*/true);
3818 return i;
3819 }
3820 else
3821 return -1;
3822 }
3823
3824 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3825 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
3826 if (TREE_CODE (val) == NOP_EXPR
3827 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
3828 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
3829 val = TREE_OPERAND (val, 0);
3830
3831 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
3832 {
3833 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
3834 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
3835 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
3836 val = decay_conversion (val, complain);
3837 }
3838
3839 if (val == error_mark_node)
3840 return -1;
3841
3842 if (type != 0)
3843 {
3844 /* Formal parm type is specified by a function prototype. */
3845 tree parmval;
3846
3847 if (!COMPLETE_TYPE_P (complete_type (type)))
3848 {
3849 if (complain & tf_error)
3850 {
3851 if (fndecl)
3852 error ("parameter %P of %qD has incomplete type %qT",
3853 i, fndecl, type);
3854 else
3855 error ("parameter %P has incomplete type %qT", i, type);
3856 }
3857 parmval = error_mark_node;
3858 }
3859 else
3860 {
3861 parmval = convert_for_initialization
3862 (NULL_TREE, type, val, flags,
3863 ICR_ARGPASS, fndecl, i, complain);
3864 parmval = convert_for_arg_passing (type, parmval, complain);
3865 }
3866
3867 if (parmval == error_mark_node)
3868 return -1;
3869
3870 (**values)[i] = parmval;
3871 }
3872 else
3873 {
3874 if (fndecl && magic_varargs_p (fndecl))
3875 /* Don't do ellipsis conversion for __built_in_constant_p
3876 as this will result in spurious errors for non-trivial
3877 types. */
3878 val = require_complete_type_sfinae (val, complain);
3879 else
3880 val = convert_arg_to_ellipsis (val, complain);
3881
3882 (**values)[i] = val;
3883 }
3884
3885 if (typetail)
3886 typetail = TREE_CHAIN (typetail);
3887 }
3888
3889 if (typetail != 0 && typetail != void_list_node)
3890 {
3891 /* See if there are default arguments that can be used. Because
3892 we hold default arguments in the FUNCTION_TYPE (which is so
3893 wrong), we can see default parameters here from deduced
3894 contexts (and via typeof) for indirect function calls.
3895 Fortunately we know whether we have a function decl to
3896 provide default arguments in a language conformant
3897 manner. */
3898 if (fndecl && TREE_PURPOSE (typetail)
3899 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
3900 {
3901 for (; typetail != void_list_node; ++i)
3902 {
3903 /* After DR777, with explicit template args we can end up with a
3904 default argument followed by no default argument. */
3905 if (!TREE_PURPOSE (typetail))
3906 break;
3907 tree parmval
3908 = convert_default_arg (TREE_VALUE (typetail),
3909 TREE_PURPOSE (typetail),
3910 fndecl, i, complain);
3911
3912 if (parmval == error_mark_node)
3913 return -1;
3914
3915 vec_safe_push (*values, parmval);
3916 typetail = TREE_CHAIN (typetail);
3917 /* ends with `...'. */
3918 if (typetail == NULL_TREE)
3919 break;
3920 }
3921 }
3922
3923 if (typetail && typetail != void_list_node)
3924 {
3925 if (complain & tf_error)
3926 error_args_num (input_location, fndecl, /*too_many_p=*/false);
3927 return -1;
3928 }
3929 }
3930
3931 return (int) i;
3932}
3933
3934/* Build a binary-operation expression, after performing default
3935 conversions on the operands. CODE is the kind of expression to
3936 build. ARG1 and ARG2 are the arguments. ARG1_CODE and ARG2_CODE
3937 are the tree codes which correspond to ARG1 and ARG2 when issuing
3938 warnings about possibly misplaced parentheses. They may differ
3939 from the TREE_CODE of ARG1 and ARG2 if the parser has done constant
3940 folding (e.g., if the parser sees "a | 1 + 1", it may call this
3941 routine with ARG2 being an INTEGER_CST and ARG2_CODE == PLUS_EXPR).
3942 To avoid issuing any parentheses warnings, pass ARG1_CODE and/or
3943 ARG2_CODE as ERROR_MARK. */
3944
3945tree
3946build_x_binary_op (location_t loc, enum tree_code code, tree arg1,
3947 enum tree_code arg1_code, tree arg2,
3948 enum tree_code arg2_code, tree *overload_p,
3949 tsubst_flags_t complain)
3950{
3951 tree orig_arg1;
3952 tree orig_arg2;
3953 tree expr;
3954 tree overload = NULL_TREE;
3955
3956 orig_arg1 = arg1;
3957 orig_arg2 = arg2;
3958
3959 if (processing_template_decl)
3960 {
3961 if (type_dependent_expression_p (arg1)
3962 || type_dependent_expression_p (arg2))
3963 return build_min_nt_loc (loc, code, arg1, arg2);
3964 arg1 = build_non_dependent_expr (arg1);
3965 arg2 = build_non_dependent_expr (arg2);
3966 }
3967
3968 if (code == DOTSTAR_EXPR)
3969 expr = build_m_component_ref (arg1, arg2, complain);
3970 else
3971 expr = build_new_op (loc, code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3972 &overload, complain);
3973
3974 if (overload_p != NULL)
3975 *overload_p = overload;
3976
3977 /* Check for cases such as x+y<<z which users are likely to
3978 misinterpret. But don't warn about obj << x + y, since that is a
3979 common idiom for I/O. */
3980 if (warn_parentheses
3981 && (complain & tf_warning)
3982 && !processing_template_decl
3983 && !error_operand_p (arg1)
3984 && !error_operand_p (arg2)
3985 && (code != LSHIFT_EXPR
3986 || !CLASS_TYPE_P (TREE_TYPE (arg1))))
3987 warn_about_parentheses (loc, code, arg1_code, orig_arg1,
3988 arg2_code, orig_arg2);
3989
3990 if (processing_template_decl && expr != error_mark_node)
3991 {
3992 if (overload != NULL_TREE)
3993 return (build_min_non_dep_op_overload
3994 (code, expr, overload, orig_arg1, orig_arg2));
3995
3996 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
3997 }
3998
3999 return expr;
4000}
4001
4002/* Build and return an ARRAY_REF expression. */
4003
4004tree
4005build_x_array_ref (location_t loc, tree arg1, tree arg2,
4006 tsubst_flags_t complain)
4007{
4008 tree orig_arg1 = arg1;
4009 tree orig_arg2 = arg2;
4010 tree expr;
4011 tree overload = NULL_TREE;
4012
4013 if (processing_template_decl)
4014 {
4015 if (type_dependent_expression_p (arg1)
4016 || type_dependent_expression_p (arg2))
4017 return build_min_nt_loc (loc, ARRAY_REF, arg1, arg2,
4018 NULL_TREE, NULL_TREE);
4019 arg1 = build_non_dependent_expr (arg1);
4020 arg2 = build_non_dependent_expr (arg2);
4021 }
4022
4023 expr = build_new_op (loc, ARRAY_REF, LOOKUP_NORMAL, arg1, arg2,
4024 NULL_TREE, &overload, complain);
4025
4026 if (processing_template_decl && expr != error_mark_node)
4027 {
4028 if (overload != NULL_TREE)
4029 return (build_min_non_dep_op_overload
4030 (ARRAY_REF, expr, overload, orig_arg1, orig_arg2));
4031
4032 return build_min_non_dep (ARRAY_REF, expr, orig_arg1, orig_arg2,
4033 NULL_TREE, NULL_TREE);
4034 }
4035 return expr;
4036}
4037
4038/* Return whether OP is an expression of enum type cast to integer
4039 type. In C++ even unsigned enum types are cast to signed integer
4040 types. We do not want to issue warnings about comparisons between
4041 signed and unsigned types when one of the types is an enum type.
4042 Those warnings are always false positives in practice. */
4043
4044static bool
4045enum_cast_to_int (tree op)
4046{
4047 if (CONVERT_EXPR_P (op)
4048 && TREE_TYPE (op) == integer_type_node
4049 && TREE_CODE (TREE_TYPE (TREE_OPERAND (op, 0))) == ENUMERAL_TYPE
4050 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op, 0))))
4051 return true;
4052
4053 /* The cast may have been pushed into a COND_EXPR. */
4054 if (TREE_CODE (op) == COND_EXPR)
4055 return (enum_cast_to_int (TREE_OPERAND (op, 1))
4056 || enum_cast_to_int (TREE_OPERAND (op, 2)));
4057
4058 return false;
4059}
4060
4061/* For the c-common bits. */
4062tree
4063build_binary_op (location_t location, enum tree_code code, tree op0, tree op1,
4064 bool /*convert_p*/)
4065{
4066 return cp_build_binary_op (location, code, op0, op1, tf_warning_or_error);
4067}
4068
4069/* Build a vector comparison of ARG0 and ARG1 using CODE opcode
4070 into a value of TYPE type. Comparison is done via VEC_COND_EXPR. */
4071
4072static tree
4073build_vec_cmp (tree_code code, tree type,
4074 tree arg0, tree arg1)
4075{
4076 tree zero_vec = build_zero_cst (type);
4077 tree minus_one_vec = build_minus_one_cst (type);
4078 tree cmp_type = build_same_sized_truth_vector_type(type);
4079 tree cmp = build2 (code, cmp_type, arg0, arg1);
4080 return build3 (VEC_COND_EXPR, type, cmp, minus_one_vec, zero_vec);
4081}
4082
4083/* Possibly warn about an address never being NULL. */
4084
4085static void
4086warn_for_null_address (location_t location, tree op, tsubst_flags_t complain)
4087{
4088 if (!warn_address
4089 || (complain & tf_warning) == 0
4090 || c_inhibit_evaluation_warnings != 0
4091 || TREE_NO_WARNING (op))
4092 return;
4093
4094 tree cop = fold_non_dependent_expr (op);
4095
4096 if (TREE_CODE (cop) == ADDR_EXPR
4097 && decl_with_nonnull_addr_p (TREE_OPERAND (cop, 0))
4098 && !TREE_NO_WARNING (cop))
4099 warning_at (location, OPT_Waddress, "the address of %qD will never "
4100 "be NULL", TREE_OPERAND (cop, 0));
4101
4102 if (CONVERT_EXPR_P (op)
4103 && TREE_CODE (TREE_TYPE (TREE_OPERAND (op, 0))) == REFERENCE_TYPE)
4104 {
4105 tree inner_op = op;
4106 STRIP_NOPS (inner_op);
4107
4108 if (DECL_P (inner_op))
4109 warning_at (location, OPT_Waddress,
4110 "the compiler can assume that the address of "
4111 "%qD will never be NULL", inner_op);
4112 }
4113}
4114
4115/* Build a binary-operation expression without default conversions.
4116 CODE is the kind of expression to build.
4117 LOCATION is the location_t of the operator in the source code.
4118 This function differs from `build' in several ways:
4119 the data type of the result is computed and recorded in it,
4120 warnings are generated if arg data types are invalid,
4121 special handling for addition and subtraction of pointers is known,
4122 and some optimization is done (operations on narrow ints
4123 are done in the narrower type when that gives the same result).
4124 Constant folding is also done before the result is returned.
4125
4126 Note that the operands will never have enumeral types
4127 because either they have just had the default conversions performed
4128 or they have both just been converted to some other type in which
4129 the arithmetic is to be done.
4130
4131 C++: must do special pointer arithmetic when implementing
4132 multiple inheritance, and deal with pointer to member functions. */
4133
4134tree
4135cp_build_binary_op (location_t location,
4136 enum tree_code code, tree orig_op0, tree orig_op1,
4137 tsubst_flags_t complain)
4138{
4139 tree op0, op1;
4140 enum tree_code code0, code1;
4141 tree type0, type1;
4142 const char *invalid_op_diag;
4143
4144 /* Expression code to give to the expression when it is built.
4145 Normally this is CODE, which is what the caller asked for,
4146 but in some special cases we change it. */
4147 enum tree_code resultcode = code;
4148
4149 /* Data type in which the computation is to be performed.
4150 In the simplest cases this is the common type of the arguments. */
4151 tree result_type = NULL_TREE;
4152
4153 /* Nonzero means operands have already been type-converted
4154 in whatever way is necessary.
4155 Zero means they need to be converted to RESULT_TYPE. */
4156 int converted = 0;
4157
4158 /* Nonzero means create the expression with this type, rather than
4159 RESULT_TYPE. */
4160 tree build_type = 0;
4161
4162 /* Nonzero means after finally constructing the expression
4163 convert it to this type. */
4164 tree final_type = 0;
4165
4166 tree result, result_ovl;
4167
4168 /* Nonzero if this is an operation like MIN or MAX which can
4169 safely be computed in short if both args are promoted shorts.
4170 Also implies COMMON.
4171 -1 indicates a bitwise operation; this makes a difference
4172 in the exact conditions for when it is safe to do the operation
4173 in a narrower mode. */
4174 int shorten = 0;
4175
4176 /* Nonzero if this is a comparison operation;
4177 if both args are promoted shorts, compare the original shorts.
4178 Also implies COMMON. */
4179 int short_compare = 0;
4180
4181 /* Nonzero means set RESULT_TYPE to the common type of the args. */
4182 int common = 0;
4183
4184 /* True if both operands have arithmetic type. */
4185 bool