1 /* Build expressions with type checking for C++ compiler.
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
5 Hacked by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
24 /* This file is part of the C++ front end.
25 It contains routines to build C++ expressions given their operands,
26 including computing the types of the result, C and C++ specific error
27 checks, and some optimization. */
31 #include "coretypes.h"
41 #include "diagnostic.h"
48 static tree pfn_from_ptrmemfunc (tree);
49 static tree delta_from_ptrmemfunc (tree);
50 static tree convert_for_assignment (tree, tree, const char *, tree, int,
52 static tree cp_pointer_int_sum (enum tree_code, tree, tree);
53 static tree rationalize_conditional_expr (enum tree_code, tree,
55 static int comp_ptr_ttypes_real (tree, tree, int);
56 static bool comp_except_types (tree, tree, bool);
57 static bool comp_array_types (const_tree, const_tree, bool);
58 static tree pointer_diff (tree, tree, tree);
59 static tree get_delta_difference (tree, tree, bool, bool);
60 static void casts_away_constness_r (tree *, tree *);
61 static bool casts_away_constness (tree, tree);
62 static void maybe_warn_about_returning_address_of_local (tree);
63 static tree lookup_destructor (tree, tree, tree);
64 static int convert_arguments (tree, VEC(tree,gc) **, tree, int,
67 /* Do `exp = require_complete_type (exp);' to make sure exp
68 does not have an incomplete type. (That includes void types.)
69 Returns the error_mark_node if the VALUE does not have
70 complete type when this function returns. */
73 require_complete_type (tree value)
77 if (processing_template_decl || value == error_mark_node)
80 if (TREE_CODE (value) == OVERLOAD)
81 type = unknown_type_node;
83 type = TREE_TYPE (value);
85 if (type == error_mark_node)
86 return error_mark_node;
88 /* First, detect a valid value with a complete type. */
89 if (COMPLETE_TYPE_P (type))
92 if (complete_type_or_else (type, value))
95 return error_mark_node;
98 /* Try to complete TYPE, if it is incomplete. For example, if TYPE is
99 a template instantiation, do the instantiation. Returns TYPE,
100 whether or not it could be completed, unless something goes
101 horribly wrong, in which case the error_mark_node is returned. */
104 complete_type (tree type)
106 if (type == NULL_TREE)
107 /* Rather than crash, we return something sure to cause an error
109 return error_mark_node;
111 if (type == error_mark_node || COMPLETE_TYPE_P (type))
113 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
115 tree t = complete_type (TREE_TYPE (type));
116 unsigned int needs_constructing, has_nontrivial_dtor;
117 if (COMPLETE_TYPE_P (t) && !dependent_type_p (type))
120 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
122 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
123 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
125 TYPE_NEEDS_CONSTRUCTING (t) = needs_constructing;
126 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = has_nontrivial_dtor;
129 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
130 instantiate_class_template (TYPE_MAIN_VARIANT (type));
135 /* Like complete_type, but issue an error if the TYPE cannot be completed.
136 VALUE is used for informative diagnostics.
137 Returns NULL_TREE if the type cannot be made complete. */
140 complete_type_or_else (tree type, tree value)
142 type = complete_type (type);
143 if (type == error_mark_node)
144 /* We already issued an error. */
146 else if (!COMPLETE_TYPE_P (type))
148 cxx_incomplete_type_diagnostic (value, type, DK_ERROR);
155 /* Return truthvalue of whether type of EXP is instantiated. */
158 type_unknown_p (const_tree exp)
160 return (TREE_CODE (exp) == TREE_LIST
161 || TREE_TYPE (exp) == unknown_type_node);
165 /* Return the common type of two parameter lists.
166 We assume that comptypes has already been done and returned 1;
167 if that isn't so, this may crash.
169 As an optimization, free the space we allocate if the parameter
170 lists are already common. */
173 commonparms (tree p1, tree p2)
175 tree oldargs = p1, newargs, n;
179 len = list_length (p1);
180 newargs = tree_last (p1);
182 if (newargs == void_list_node)
191 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
196 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
198 if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
200 TREE_PURPOSE (n) = TREE_PURPOSE (p1);
203 else if (! TREE_PURPOSE (p1))
205 if (TREE_PURPOSE (p2))
207 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
213 if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
215 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
217 if (TREE_VALUE (p1) != TREE_VALUE (p2))
220 TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2));
223 TREE_VALUE (n) = TREE_VALUE (p1);
231 /* Given a type, perhaps copied for a typedef,
232 find the "original" version of it. */
234 original_type (tree t)
236 int quals = cp_type_quals (t);
237 while (t != error_mark_node
238 && TYPE_NAME (t) != NULL_TREE)
240 tree x = TYPE_NAME (t);
241 if (TREE_CODE (x) != TYPE_DECL)
243 x = DECL_ORIGINAL_TYPE (x);
248 return cp_build_qualified_type (t, quals);
251 /* Return the common type for two arithmetic types T1 and T2 under the
252 usual arithmetic conversions. The default conversions have already
253 been applied, and enumerated types converted to their compatible
257 cp_common_type (tree t1, tree t2)
259 enum tree_code code1 = TREE_CODE (t1);
260 enum tree_code code2 = TREE_CODE (t2);
263 /* In what follows, we slightly generalize the rules given in [expr] so
264 as to deal with `long long' and `complex'. First, merge the
266 attributes = (*targetm.merge_type_attributes) (t1, t2);
268 if (SCOPED_ENUM_P (t1) || SCOPED_ENUM_P (t2))
270 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
271 return build_type_attribute_variant (t1, attributes);
276 /* FIXME: Attributes. */
277 gcc_assert (ARITHMETIC_TYPE_P (t1)
278 || TREE_CODE (t1) == VECTOR_TYPE
279 || UNSCOPED_ENUM_P (t1));
280 gcc_assert (ARITHMETIC_TYPE_P (t2)
281 || TREE_CODE (t2) == VECTOR_TYPE
282 || UNSCOPED_ENUM_P (t2));
284 /* If one type is complex, form the common type of the non-complex
285 components, then make that complex. Use T1 or T2 if it is the
287 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
289 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
290 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
292 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
294 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
295 return build_type_attribute_variant (t1, attributes);
296 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
297 return build_type_attribute_variant (t2, attributes);
299 return build_type_attribute_variant (build_complex_type (subtype),
303 if (code1 == VECTOR_TYPE)
305 /* When we get here we should have two vectors of the same size.
306 Just prefer the unsigned one if present. */
307 if (TYPE_UNSIGNED (t1))
308 return build_type_attribute_variant (t1, attributes);
310 return build_type_attribute_variant (t2, attributes);
313 /* If only one is real, use it as the result. */
314 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
315 return build_type_attribute_variant (t1, attributes);
316 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
317 return build_type_attribute_variant (t2, attributes);
319 /* Both real or both integers; use the one with greater precision. */
320 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
321 return build_type_attribute_variant (t1, attributes);
322 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
323 return build_type_attribute_variant (t2, attributes);
325 /* The types are the same; no need to do anything fancy. */
326 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
327 return build_type_attribute_variant (t1, attributes);
329 if (code1 != REAL_TYPE)
331 /* If one is unsigned long long, then convert the other to unsigned
333 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
334 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
335 return build_type_attribute_variant (long_long_unsigned_type_node,
337 /* If one is a long long, and the other is an unsigned long, and
338 long long can represent all the values of an unsigned long, then
339 convert to a long long. Otherwise, convert to an unsigned long
340 long. Otherwise, if either operand is long long, convert the
343 Since we're here, we know the TYPE_PRECISION is the same;
344 therefore converting to long long cannot represent all the values
345 of an unsigned long, so we choose unsigned long long in that
347 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
348 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
350 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
351 ? long_long_unsigned_type_node
352 : long_long_integer_type_node);
353 return build_type_attribute_variant (t, attributes);
356 /* Go through the same procedure, but for longs. */
357 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
358 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
359 return build_type_attribute_variant (long_unsigned_type_node,
361 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
362 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
364 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
365 ? long_unsigned_type_node : long_integer_type_node);
366 return build_type_attribute_variant (t, attributes);
368 /* Otherwise prefer the unsigned one. */
369 if (TYPE_UNSIGNED (t1))
370 return build_type_attribute_variant (t1, attributes);
372 return build_type_attribute_variant (t2, attributes);
376 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
377 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
378 return build_type_attribute_variant (long_double_type_node,
380 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
381 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
382 return build_type_attribute_variant (double_type_node,
384 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
385 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
386 return build_type_attribute_variant (float_type_node,
389 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
390 the standard C++ floating-point types. Logic earlier in this
391 function has already eliminated the possibility that
392 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
393 compelling reason to choose one or the other. */
394 return build_type_attribute_variant (t1, attributes);
398 /* T1 and T2 are arithmetic or enumeration types. Return the type
399 that will result from the "usual arithmetic conversions" on T1 and
400 T2 as described in [expr]. */
403 type_after_usual_arithmetic_conversions (tree t1, tree t2)
405 gcc_assert (ARITHMETIC_TYPE_P (t1)
406 || TREE_CODE (t1) == VECTOR_TYPE
407 || UNSCOPED_ENUM_P (t1));
408 gcc_assert (ARITHMETIC_TYPE_P (t2)
409 || TREE_CODE (t2) == VECTOR_TYPE
410 || UNSCOPED_ENUM_P (t2));
412 /* Perform the integral promotions. We do not promote real types here. */
413 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t1)
414 && INTEGRAL_OR_ENUMERATION_TYPE_P (t2))
416 t1 = type_promotes_to (t1);
417 t2 = type_promotes_to (t2);
420 return cp_common_type (t1, t2);
423 /* Subroutine of composite_pointer_type to implement the recursive
424 case. See that function for documentation fo the parameters. */
427 composite_pointer_type_r (tree t1, tree t2, const char* location,
428 tsubst_flags_t complain)
435 /* Determine the types pointed to by T1 and T2. */
436 if (TREE_CODE (t1) == POINTER_TYPE)
438 pointee1 = TREE_TYPE (t1);
439 pointee2 = TREE_TYPE (t2);
443 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
444 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
449 Otherwise, the composite pointer type is a pointer type
450 similar (_conv.qual_) to the type of one of the operands,
451 with a cv-qualification signature (_conv.qual_) that is the
452 union of the cv-qualification signatures of the operand
454 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
455 result_type = pointee1;
456 else if ((TREE_CODE (pointee1) == POINTER_TYPE
457 && TREE_CODE (pointee2) == POINTER_TYPE)
458 || (TYPE_PTR_TO_MEMBER_P (pointee1)
459 && TYPE_PTR_TO_MEMBER_P (pointee2)))
460 result_type = composite_pointer_type_r (pointee1, pointee2, location,
464 if (complain & tf_error)
465 permerror (input_location, "%s between distinct pointer types %qT and %qT "
468 result_type = void_type_node;
470 result_type = cp_build_qualified_type (result_type,
471 (cp_type_quals (pointee1)
472 | cp_type_quals (pointee2)));
473 /* If the original types were pointers to members, so is the
475 if (TYPE_PTR_TO_MEMBER_P (t1))
477 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
478 TYPE_PTRMEM_CLASS_TYPE (t2))
479 && (complain & tf_error))
480 permerror (input_location, "%s between distinct pointer types %qT and %qT "
483 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
487 result_type = build_pointer_type (result_type);
489 /* Merge the attributes. */
490 attributes = (*targetm.merge_type_attributes) (t1, t2);
491 return build_type_attribute_variant (result_type, attributes);
494 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
495 ARG1 and ARG2 are the values with those types. The LOCATION is a
496 string describing the current location, in case an error occurs.
498 This routine also implements the computation of a common type for
499 pointers-to-members as per [expr.eq]. */
502 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
503 const char* location, tsubst_flags_t complain)
510 If one operand is a null pointer constant, the composite pointer
511 type is the type of the other operand. */
512 if (null_ptr_cst_p (arg1))
514 if (null_ptr_cst_p (arg2))
521 If one of the operands has type "pointer to cv1 void*", then
522 the other has type "pointer to cv2T", and the composite pointer
523 type is "pointer to cv12 void", where cv12 is the union of cv1
526 If either type is a pointer to void, make sure it is T1. */
527 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
535 /* Now, if T1 is a pointer to void, merge the qualifiers. */
536 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
541 if (TYPE_PTRFN_P (t2) && (complain & tf_error))
542 pedwarn (input_location, OPT_pedantic, "ISO C++ forbids %s "
543 "between pointer of type %<void *%> and pointer-to-function",
546 = cp_build_qualified_type (void_type_node,
547 (cp_type_quals (TREE_TYPE (t1))
548 | cp_type_quals (TREE_TYPE (t2))));
549 result_type = build_pointer_type (result_type);
550 /* Merge the attributes. */
551 attributes = (*targetm.merge_type_attributes) (t1, t2);
552 return build_type_attribute_variant (result_type, attributes);
555 if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE
556 && TREE_CODE (t2) == POINTER_TYPE)
558 if (objc_compare_types (t1, t2, -3, NULL_TREE))
562 /* [expr.eq] permits the application of a pointer conversion to
563 bring the pointers to a common type. */
564 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
565 && CLASS_TYPE_P (TREE_TYPE (t1))
566 && CLASS_TYPE_P (TREE_TYPE (t2))
567 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
570 class1 = TREE_TYPE (t1);
571 class2 = TREE_TYPE (t2);
573 if (DERIVED_FROM_P (class1, class2))
574 t2 = (build_pointer_type
575 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
576 else if (DERIVED_FROM_P (class2, class1))
577 t1 = (build_pointer_type
578 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
581 if (complain & tf_error)
582 error ("%s between distinct pointer types %qT and %qT "
583 "lacks a cast", location, t1, t2);
584 return error_mark_node;
587 /* [expr.eq] permits the application of a pointer-to-member
588 conversion to change the class type of one of the types. */
589 else if (TYPE_PTR_TO_MEMBER_P (t1)
590 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
591 TYPE_PTRMEM_CLASS_TYPE (t2)))
593 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
594 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
596 if (DERIVED_FROM_P (class1, class2))
597 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
598 else if (DERIVED_FROM_P (class2, class1))
599 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
602 if (complain & tf_error)
603 error ("%s between distinct pointer-to-member types %qT and %qT "
604 "lacks a cast", location, t1, t2);
605 return error_mark_node;
609 return composite_pointer_type_r (t1, t2, location, complain);
612 /* Return the merged type of two types.
613 We assume that comptypes has already been done and returned 1;
614 if that isn't so, this may crash.
616 This just combines attributes and default arguments; any other
617 differences would cause the two types to compare unalike. */
620 merge_types (tree t1, tree t2)
622 enum tree_code code1;
623 enum tree_code code2;
626 /* Save time if the two types are the same. */
629 if (original_type (t1) == original_type (t2))
632 /* If one type is nonsense, use the other. */
633 if (t1 == error_mark_node)
635 if (t2 == error_mark_node)
638 /* Merge the attributes. */
639 attributes = (*targetm.merge_type_attributes) (t1, t2);
641 if (TYPE_PTRMEMFUNC_P (t1))
642 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
643 if (TYPE_PTRMEMFUNC_P (t2))
644 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
646 code1 = TREE_CODE (t1);
647 code2 = TREE_CODE (t2);
650 gcc_assert (code1 == TYPENAME_TYPE || code2 == TYPENAME_TYPE);
651 if (code1 == TYPENAME_TYPE)
653 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
654 code1 = TREE_CODE (t1);
658 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
659 code2 = TREE_CODE (t2);
667 /* For two pointers, do this recursively on the target type. */
669 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
670 int quals = cp_type_quals (t1);
672 if (code1 == POINTER_TYPE)
673 t1 = build_pointer_type (target);
675 t1 = cp_build_reference_type (target, TYPE_REF_IS_RVALUE (t1));
676 t1 = build_type_attribute_variant (t1, attributes);
677 t1 = cp_build_qualified_type (t1, quals);
679 if (TREE_CODE (target) == METHOD_TYPE)
680 t1 = build_ptrmemfunc_type (t1);
689 quals = cp_type_quals (t1);
690 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
691 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
692 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
694 t1 = cp_build_qualified_type (t1, quals);
700 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
701 /* Save space: see if the result is identical to one of the args. */
702 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
703 return build_type_attribute_variant (t1, attributes);
704 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
705 return build_type_attribute_variant (t2, attributes);
706 /* Merge the element types, and have a size if either arg has one. */
707 t1 = build_cplus_array_type
708 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
713 /* Function types: prefer the one that specified arg types.
714 If both do, merge the arg types. Also merge the return types. */
716 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
717 tree p1 = TYPE_ARG_TYPES (t1);
718 tree p2 = TYPE_ARG_TYPES (t2);
721 /* Save space: see if the result is identical to one of the args. */
722 if (valtype == TREE_TYPE (t1) && ! p2)
723 return cp_build_type_attribute_variant (t1, attributes);
724 if (valtype == TREE_TYPE (t2) && ! p1)
725 return cp_build_type_attribute_variant (t2, attributes);
727 /* Simple way if one arg fails to specify argument types. */
728 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
730 rval = build_function_type (valtype, p2);
731 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
732 rval = build_exception_variant (rval, raises);
733 return cp_build_type_attribute_variant (rval, attributes);
735 raises = TYPE_RAISES_EXCEPTIONS (t1);
736 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
738 rval = build_function_type (valtype, p1);
740 rval = build_exception_variant (rval, raises);
741 return cp_build_type_attribute_variant (rval, attributes);
744 rval = build_function_type (valtype, commonparms (p1, p2));
745 t1 = build_exception_variant (rval, raises);
751 /* Get this value the long way, since TYPE_METHOD_BASETYPE
752 is just the main variant of this. */
753 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
754 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
757 /* If this was a member function type, get back to the
758 original type of type member function (i.e., without
759 the class instance variable up front. */
760 t1 = build_function_type (TREE_TYPE (t1),
761 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
762 t2 = build_function_type (TREE_TYPE (t2),
763 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
764 t3 = merge_types (t1, t2);
765 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
766 TYPE_ARG_TYPES (t3));
767 t1 = build_exception_variant (t3, raises);
772 /* There is no need to merge attributes into a TYPENAME_TYPE.
773 When the type is instantiated it will have whatever
774 attributes result from the instantiation. */
780 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
782 else if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
785 return cp_build_type_attribute_variant (t1, attributes);
788 /* Wrapper around cp_common_type that is used by c-common.c and other
789 front end optimizations that remove promotions.
791 Return the common type for two arithmetic types T1 and T2 under the
792 usual arithmetic conversions. The default conversions have already
793 been applied, and enumerated types converted to their compatible
797 common_type (tree t1, tree t2)
799 /* If one type is nonsense, use the other */
800 if (t1 == error_mark_node)
802 if (t2 == error_mark_node)
805 return cp_common_type (t1, t2);
808 /* Return the common type of two pointer types T1 and T2. This is the
809 type for the result of most arithmetic operations if the operands
810 have the given two types.
812 We assume that comp_target_types has already been done and returned
813 nonzero; if that isn't so, this may crash. */
816 common_pointer_type (tree t1, tree t2)
818 gcc_assert ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
819 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
820 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)));
822 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
823 "conversion", tf_warning_or_error);
826 /* Compare two exception specifier types for exactness or subsetness, if
827 allowed. Returns false for mismatch, true for match (same, or
830 [except.spec] "If a class X ... objects of class X or any class publicly
831 and unambiguously derived from X. Similarly, if a pointer type Y * ...
832 exceptions of type Y * or that are pointers to any type publicly and
833 unambiguously derived from Y. Otherwise a function only allows exceptions
834 that have the same type ..."
835 This does not mention cv qualifiers and is different to what throw
836 [except.throw] and catch [except.catch] will do. They will ignore the
837 top level cv qualifiers, and allow qualifiers in the pointer to class
840 We implement the letter of the standard. */
843 comp_except_types (tree a, tree b, bool exact)
845 if (same_type_p (a, b))
849 if (cp_type_quals (a) || cp_type_quals (b))
852 if (TREE_CODE (a) == POINTER_TYPE
853 && TREE_CODE (b) == POINTER_TYPE)
857 if (cp_type_quals (a) || cp_type_quals (b))
861 if (TREE_CODE (a) != RECORD_TYPE
862 || TREE_CODE (b) != RECORD_TYPE)
865 if (PUBLICLY_UNIQUELY_DERIVED_P (a, b))
871 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
872 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
873 otherwise it must be exact. Exception lists are unordered, but
874 we've already filtered out duplicates. Most lists will be in order,
875 we should try to make use of that. */
878 comp_except_specs (const_tree t1, const_tree t2, bool exact)
887 if (t1 == NULL_TREE) /* T1 is ... */
888 return t2 == NULL_TREE || !exact;
889 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
890 return t2 != NULL_TREE && !TREE_VALUE (t2);
891 if (t2 == NULL_TREE) /* T2 is ... */
893 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
896 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
897 Count how many we find, to determine exactness. For exact matching and
898 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
900 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
902 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
904 tree a = TREE_VALUE (probe);
905 tree b = TREE_VALUE (t2);
907 if (comp_except_types (a, b, exact))
909 if (probe == base && exact)
910 base = TREE_CHAIN (probe);
915 if (probe == NULL_TREE)
918 return !exact || base == NULL_TREE || length == list_length (t1);
921 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
922 [] can match [size]. */
925 comp_array_types (const_tree t1, const_tree t2, bool allow_redeclaration)
934 /* The type of the array elements must be the same. */
935 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
938 d1 = TYPE_DOMAIN (t1);
939 d2 = TYPE_DOMAIN (t2);
944 /* If one of the arrays is dimensionless, and the other has a
945 dimension, they are of different types. However, it is valid to
953 declarations for an array object can specify
954 array types that differ by the presence or absence of a major
955 array bound (_dcl.array_). */
957 return allow_redeclaration;
959 /* Check that the dimensions are the same. */
961 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
963 max1 = TYPE_MAX_VALUE (d1);
964 max2 = TYPE_MAX_VALUE (d2);
965 if (processing_template_decl && !abi_version_at_least (2)
966 && !value_dependent_expression_p (max1)
967 && !value_dependent_expression_p (max2))
969 /* With abi-1 we do not fold non-dependent array bounds, (and
970 consequently mangle them incorrectly). We must therefore
971 fold them here, to verify the domains have the same
977 if (!cp_tree_equal (max1, max2))
983 /* Subroutine in comptypes. */
986 structural_comptypes (tree t1, tree t2, int strict)
991 /* Suppress errors caused by previously reported errors. */
992 if (t1 == error_mark_node || t2 == error_mark_node)
995 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
997 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
998 current instantiation. */
999 if (TREE_CODE (t1) == TYPENAME_TYPE)
1000 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
1002 if (TREE_CODE (t2) == TYPENAME_TYPE)
1003 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
1005 if (TYPE_PTRMEMFUNC_P (t1))
1006 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
1007 if (TYPE_PTRMEMFUNC_P (t2))
1008 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
1010 /* Different classes of types can't be compatible. */
1011 if (TREE_CODE (t1) != TREE_CODE (t2))
1014 /* Qualifiers must match. For array types, we will check when we
1015 recur on the array element types. */
1016 if (TREE_CODE (t1) != ARRAY_TYPE
1017 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
1019 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
1022 /* Allow for two different type nodes which have essentially the same
1023 definition. Note that we already checked for equality of the type
1024 qualifiers (just above). */
1026 if (TREE_CODE (t1) != ARRAY_TYPE
1027 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
1030 /* Compare the types. Break out if they could be the same. */
1031 switch (TREE_CODE (t1))
1035 /* All void and bool types are the same. */
1039 case FIXED_POINT_TYPE:
1041 /* With these nodes, we can't determine type equivalence by
1042 looking at what is stored in the nodes themselves, because
1043 two nodes might have different TYPE_MAIN_VARIANTs but still
1044 represent the same type. For example, wchar_t and int could
1045 have the same properties (TYPE_PRECISION, TYPE_MIN_VALUE,
1046 TYPE_MAX_VALUE, etc.), but have different TYPE_MAIN_VARIANTs
1047 and are distinct types. On the other hand, int and the
1050 typedef int INT __attribute((may_alias));
1052 have identical properties, different TYPE_MAIN_VARIANTs, but
1053 represent the same type. The canonical type system keeps
1054 track of equivalence in this case, so we fall back on it. */
1055 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1057 case TEMPLATE_TEMPLATE_PARM:
1058 case BOUND_TEMPLATE_TEMPLATE_PARM:
1059 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1060 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2)
1061 || (TEMPLATE_TYPE_PARAMETER_PACK (t1)
1062 != TEMPLATE_TYPE_PARAMETER_PACK (t2)))
1064 if (!comp_template_parms
1065 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1066 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1068 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1070 /* Don't check inheritance. */
1071 strict = COMPARE_STRICT;
1076 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1077 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1078 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1079 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1082 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1084 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1090 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1091 strict & ~COMPARE_REDECLARATION))
1093 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1097 case REFERENCE_TYPE:
1098 if (TYPE_REF_IS_RVALUE (t1) != TYPE_REF_IS_RVALUE (t2))
1100 /* fall through to checks for pointer types */
1103 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1104 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)
1105 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1111 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1113 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1118 /* Target types must match incl. qualifiers. */
1119 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1123 case TEMPLATE_TYPE_PARM:
1124 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1125 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2)
1126 || (TEMPLATE_TYPE_PARAMETER_PACK (t1)
1127 != TEMPLATE_TYPE_PARAMETER_PACK (t2)))
1132 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1133 TYPENAME_TYPE_FULLNAME (t2)))
1135 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1139 case UNBOUND_CLASS_TEMPLATE:
1140 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1142 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1147 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1152 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1153 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1157 case TYPE_PACK_EXPANSION:
1158 return same_type_p (PACK_EXPANSION_PATTERN (t1),
1159 PACK_EXPANSION_PATTERN (t2));
1162 if (DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t1)
1163 != DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t2)
1164 || !cp_tree_equal (DECLTYPE_TYPE_EXPR (t1),
1165 DECLTYPE_TYPE_EXPR (t2)))
1173 /* If we get here, we know that from a target independent POV the
1174 types are the same. Make sure the target attributes are also
1176 return targetm.comp_type_attributes (t1, t2);
1179 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
1180 is a bitwise-or of the COMPARE_* flags. */
1183 comptypes (tree t1, tree t2, int strict)
1185 if (strict == COMPARE_STRICT)
1190 if (t1 == error_mark_node || t2 == error_mark_node)
1193 if (TYPE_STRUCTURAL_EQUALITY_P (t1) || TYPE_STRUCTURAL_EQUALITY_P (t2))
1194 /* At least one of the types requires structural equality, so
1195 perform a deep check. */
1196 return structural_comptypes (t1, t2, strict);
1198 #ifdef ENABLE_CHECKING
1199 if (USE_CANONICAL_TYPES)
1201 bool result = structural_comptypes (t1, t2, strict);
1203 if (result && TYPE_CANONICAL (t1) != TYPE_CANONICAL (t2))
1204 /* The two types are structurally equivalent, but their
1205 canonical types were different. This is a failure of the
1206 canonical type propagation code.*/
1208 ("canonical types differ for identical types %T and %T",
1210 else if (!result && TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2))
1211 /* Two types are structurally different, but the canonical
1212 types are the same. This means we were over-eager in
1213 assigning canonical types. */
1215 ("same canonical type node for different types %T and %T",
1221 if (USE_CANONICAL_TYPES)
1222 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1225 return structural_comptypes (t1, t2, strict);
1227 else if (strict == COMPARE_STRUCTURAL)
1228 return structural_comptypes (t1, t2, COMPARE_STRICT);
1230 return structural_comptypes (t1, t2, strict);
1233 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1236 at_least_as_qualified_p (const_tree type1, const_tree type2)
1238 int q1 = cp_type_quals (type1);
1239 int q2 = cp_type_quals (type2);
1241 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1242 return (q1 & q2) == q2;
1245 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1246 more cv-qualified that TYPE1, and 0 otherwise. */
1249 comp_cv_qualification (const_tree type1, const_tree type2)
1251 int q1 = cp_type_quals (type1);
1252 int q2 = cp_type_quals (type2);
1257 if ((q1 & q2) == q2)
1259 else if ((q1 & q2) == q1)
1265 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1266 subset of the cv-qualification signature of TYPE2, and the types
1267 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1270 comp_cv_qual_signature (tree type1, tree type2)
1272 if (comp_ptr_ttypes_real (type2, type1, -1))
1274 else if (comp_ptr_ttypes_real (type1, type2, -1))
1280 /* Subroutines of `comptypes'. */
1282 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1283 equivalent in the sense that functions with those parameter types
1284 can have equivalent types. The two lists must be equivalent,
1285 element by element. */
1288 compparms (const_tree parms1, const_tree parms2)
1292 /* An unspecified parmlist matches any specified parmlist
1293 whose argument types don't need default promotions. */
1295 for (t1 = parms1, t2 = parms2;
1297 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1299 /* If one parmlist is shorter than the other,
1300 they fail to match. */
1303 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1310 /* Process a sizeof or alignof expression where the operand is a
1314 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1319 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1320 if (type == error_mark_node)
1321 return error_mark_node;
1323 type = non_reference (type);
1324 if (TREE_CODE (type) == METHOD_TYPE)
1327 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
1328 "invalid application of %qs to a member function",
1329 operator_name_info[(int) op].name);
1330 value = size_one_node;
1333 dependent_p = dependent_type_p (type);
1335 complete_type (type);
1337 /* VLA types will have a non-constant size. In the body of an
1338 uninstantiated template, we don't need to try to compute the
1339 value, because the sizeof expression is not an integral
1340 constant expression in that case. And, if we do try to
1341 compute the value, we'll likely end up with SAVE_EXPRs, which
1342 the template substitution machinery does not expect to see. */
1343 || (processing_template_decl
1344 && COMPLETE_TYPE_P (type)
1345 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST))
1347 value = build_min (op, size_type_node, type);
1348 TREE_READONLY (value) = 1;
1352 return c_sizeof_or_alignof_type (input_location, complete_type (type),
1357 /* Return the size of the type, without producing any warnings for
1358 types whose size cannot be taken. This routine should be used only
1359 in some other routine that has already produced a diagnostic about
1360 using the size of such a type. */
1362 cxx_sizeof_nowarn (tree type)
1364 if (TREE_CODE (type) == FUNCTION_TYPE
1365 || TREE_CODE (type) == VOID_TYPE
1366 || TREE_CODE (type) == ERROR_MARK)
1367 return size_one_node;
1368 else if (!COMPLETE_TYPE_P (type))
1369 return size_zero_node;
1371 return cxx_sizeof_or_alignof_type (type, SIZEOF_EXPR, false);
1374 /* Process a sizeof expression where the operand is an expression. */
1377 cxx_sizeof_expr (tree e, tsubst_flags_t complain)
1379 if (e == error_mark_node)
1380 return error_mark_node;
1382 if (processing_template_decl)
1384 e = build_min (SIZEOF_EXPR, size_type_node, e);
1385 TREE_SIDE_EFFECTS (e) = 0;
1386 TREE_READONLY (e) = 1;
1391 if (TREE_CODE (e) == COMPONENT_REF
1392 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1393 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1395 if (complain & tf_error)
1396 error ("invalid application of %<sizeof%> to a bit-field");
1398 return error_mark_node;
1401 else if (is_overloaded_fn (e))
1403 if (complain & tf_error)
1404 permerror (input_location, "ISO C++ forbids applying %<sizeof%> to an expression of "
1407 return error_mark_node;
1410 else if (type_unknown_p (e))
1412 if (complain & tf_error)
1413 cxx_incomplete_type_error (e, TREE_TYPE (e));
1415 return error_mark_node;
1421 return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, complain & tf_error);
1424 /* Implement the __alignof keyword: Return the minimum required
1425 alignment of E, measured in bytes. For VAR_DECL's and
1426 FIELD_DECL's return DECL_ALIGN (which can be set from an
1427 "aligned" __attribute__ specification). */
1430 cxx_alignof_expr (tree e, tsubst_flags_t complain)
1434 if (e == error_mark_node)
1435 return error_mark_node;
1437 if (processing_template_decl)
1439 e = build_min (ALIGNOF_EXPR, size_type_node, e);
1440 TREE_SIDE_EFFECTS (e) = 0;
1441 TREE_READONLY (e) = 1;
1446 if (TREE_CODE (e) == VAR_DECL)
1447 t = size_int (DECL_ALIGN_UNIT (e));
1448 else if (TREE_CODE (e) == COMPONENT_REF
1449 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1450 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1452 if (complain & tf_error)
1453 error ("invalid application of %<__alignof%> to a bit-field");
1455 return error_mark_node;
1458 else if (TREE_CODE (e) == COMPONENT_REF
1459 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL)
1460 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1)));
1461 else if (is_overloaded_fn (e))
1463 if (complain & tf_error)
1464 permerror (input_location, "ISO C++ forbids applying %<__alignof%> to an expression of "
1467 return error_mark_node;
1468 if (TREE_CODE (e) == FUNCTION_DECL)
1469 t = size_int (DECL_ALIGN_UNIT (e));
1473 else if (type_unknown_p (e))
1475 if (complain & tf_error)
1476 cxx_incomplete_type_error (e, TREE_TYPE (e));
1478 return error_mark_node;
1482 return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR,
1483 complain & tf_error);
1485 return fold_convert (size_type_node, t);
1488 /* Process a sizeof or alignof expression E with code OP where the operand
1489 is an expression. */
1492 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op, bool complain)
1494 if (op == SIZEOF_EXPR)
1495 return cxx_sizeof_expr (e, complain? tf_warning_or_error : tf_none);
1497 return cxx_alignof_expr (e, complain? tf_warning_or_error : tf_none);
1500 /* EXPR is being used in a context that is not a function call.
1505 The expression can be used only as the left-hand operand of a
1506 member function call.
1508 [expr.mptr.operator]
1510 If the result of .* or ->* is a function, then that result can be
1511 used only as the operand for the function call operator ().
1513 by issuing an error message if appropriate. Returns true iff EXPR
1514 violates these rules. */
1517 invalid_nonstatic_memfn_p (const_tree expr, tsubst_flags_t complain)
1519 if (expr && DECL_NONSTATIC_MEMBER_FUNCTION_P (expr))
1521 if (complain & tf_error)
1522 error ("invalid use of non-static member function");
1528 /* If EXP is a reference to a bitfield, and the type of EXP does not
1529 match the declared type of the bitfield, return the declared type
1530 of the bitfield. Otherwise, return NULL_TREE. */
1533 is_bitfield_expr_with_lowered_type (const_tree exp)
1535 switch (TREE_CODE (exp))
1538 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)
1539 ? TREE_OPERAND (exp, 1)
1540 : TREE_OPERAND (exp, 0)))
1542 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2));
1545 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1));
1549 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1555 field = TREE_OPERAND (exp, 1);
1556 if (TREE_CODE (field) != FIELD_DECL || !DECL_BIT_FIELD_TYPE (field))
1558 if (same_type_ignoring_top_level_qualifiers_p
1559 (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field)))
1561 return DECL_BIT_FIELD_TYPE (field);
1565 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (exp, 0)))
1566 == TYPE_MAIN_VARIANT (TREE_TYPE (exp)))
1567 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1575 /* Like is_bitfield_with_lowered_type, except that if EXP is not a
1576 bitfield with a lowered type, the type of EXP is returned, rather
1580 unlowered_expr_type (const_tree exp)
1584 type = is_bitfield_expr_with_lowered_type (exp);
1586 type = TREE_TYPE (exp);
1591 /* Perform the conversions in [expr] that apply when an lvalue appears
1592 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1593 function-to-pointer conversions. In addition, manifest constants
1594 are replaced by their values, and bitfield references are converted
1595 to their declared types.
1597 Although the returned value is being used as an rvalue, this
1598 function does not wrap the returned expression in a
1599 NON_LVALUE_EXPR; the caller is expected to be mindful of the fact
1600 that the return value is no longer an lvalue. */
1603 decay_conversion (tree exp)
1606 enum tree_code code;
1608 type = TREE_TYPE (exp);
1609 if (type == error_mark_node)
1610 return error_mark_node;
1612 if (type_unknown_p (exp))
1614 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1615 return error_mark_node;
1618 exp = decl_constant_value (exp);
1619 if (error_operand_p (exp))
1620 return error_mark_node;
1622 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1623 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1624 code = TREE_CODE (type);
1625 if (code == VOID_TYPE)
1627 error ("void value not ignored as it ought to be");
1628 return error_mark_node;
1630 if (invalid_nonstatic_memfn_p (exp, tf_warning_or_error))
1631 return error_mark_node;
1632 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1633 return cp_build_unary_op (ADDR_EXPR, exp, 0, tf_warning_or_error);
1634 if (code == ARRAY_TYPE)
1639 if (TREE_CODE (exp) == INDIRECT_REF)
1640 return build_nop (build_pointer_type (TREE_TYPE (type)),
1641 TREE_OPERAND (exp, 0));
1643 if (TREE_CODE (exp) == COMPOUND_EXPR)
1645 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1646 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1647 TREE_OPERAND (exp, 0), op1);
1651 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1653 error ("invalid use of non-lvalue array");
1654 return error_mark_node;
1657 ptrtype = build_pointer_type (TREE_TYPE (type));
1659 if (TREE_CODE (exp) == VAR_DECL)
1661 if (!cxx_mark_addressable (exp))
1662 return error_mark_node;
1663 adr = build_nop (ptrtype, build_address (exp));
1666 /* This way is better for a COMPONENT_REF since it can
1667 simplify the offset for a component. */
1668 adr = cp_build_unary_op (ADDR_EXPR, exp, 1, tf_warning_or_error);
1669 return cp_convert (ptrtype, adr);
1672 /* If a bitfield is used in a context where integral promotion
1673 applies, then the caller is expected to have used
1674 default_conversion. That function promotes bitfields correctly
1675 before calling this function. At this point, if we have a
1676 bitfield referenced, we may assume that is not subject to
1677 promotion, and that, therefore, the type of the resulting rvalue
1678 is the declared type of the bitfield. */
1679 exp = convert_bitfield_to_declared_type (exp);
1681 /* We do not call rvalue() here because we do not want to wrap EXP
1682 in a NON_LVALUE_EXPR. */
1686 Non-class rvalues always have cv-unqualified types. */
1687 type = TREE_TYPE (exp);
1688 if (!CLASS_TYPE_P (type) && cp_type_quals (type))
1689 exp = build_nop (TYPE_MAIN_VARIANT (type), exp);
1694 /* Perform preparatory conversions, as part of the "usual arithmetic
1695 conversions". In particular, as per [expr]:
1697 Whenever an lvalue expression appears as an operand of an
1698 operator that expects the rvalue for that operand, the
1699 lvalue-to-rvalue, array-to-pointer, or function-to-pointer
1700 standard conversions are applied to convert the expression to an
1703 In addition, we perform integral promotions here, as those are
1704 applied to both operands to a binary operator before determining
1705 what additional conversions should apply. */
1708 default_conversion (tree exp)
1710 /* Check for target-specific promotions. */
1711 tree promoted_type = targetm.promoted_type (TREE_TYPE (exp));
1713 exp = cp_convert (promoted_type, exp);
1714 /* Perform the integral promotions first so that bitfield
1715 expressions (which may promote to "int", even if the bitfield is
1716 declared "unsigned") are promoted correctly. */
1717 else if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1718 exp = perform_integral_promotions (exp);
1719 /* Perform the other conversions. */
1720 exp = decay_conversion (exp);
1725 /* EXPR is an expression with an integral or enumeration type.
1726 Perform the integral promotions in [conv.prom], and return the
1730 perform_integral_promotions (tree expr)
1737 If the bitfield has an enumerated type, it is treated as any
1738 other value of that type for promotion purposes. */
1739 type = is_bitfield_expr_with_lowered_type (expr);
1740 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
1741 type = TREE_TYPE (expr);
1742 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1743 promoted_type = type_promotes_to (type);
1744 if (type != promoted_type)
1745 expr = cp_convert (promoted_type, expr);
1749 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1750 decay_conversion to one. */
1753 string_conv_p (const_tree totype, const_tree exp, int warn)
1757 if (TREE_CODE (totype) != POINTER_TYPE)
1760 t = TREE_TYPE (totype);
1761 if (!same_type_p (t, char_type_node)
1762 && !same_type_p (t, char16_type_node)
1763 && !same_type_p (t, char32_type_node)
1764 && !same_type_p (t, wchar_type_node))
1767 if (TREE_CODE (exp) == STRING_CST)
1769 /* Make sure that we don't try to convert between char and wide chars. */
1770 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1775 /* Is this a string constant which has decayed to 'const char *'? */
1776 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1777 if (!same_type_p (TREE_TYPE (exp), t))
1780 if (TREE_CODE (exp) != ADDR_EXPR
1781 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1785 /* This warning is not very useful, as it complains about printf. */
1787 warning (OPT_Wwrite_strings,
1788 "deprecated conversion from string constant to %qT",
1794 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1795 can, for example, use as an lvalue. This code used to be in
1796 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1797 expressions, where we're dealing with aggregates. But now it's again only
1798 called from unary_complex_lvalue. The case (in particular) that led to
1799 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1803 rationalize_conditional_expr (enum tree_code code, tree t,
1804 tsubst_flags_t complain)
1806 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1807 the first operand is always the one to be used if both operands
1808 are equal, so we know what conditional expression this used to be. */
1809 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1811 tree op0 = TREE_OPERAND (t, 0);
1812 tree op1 = TREE_OPERAND (t, 1);
1814 /* The following code is incorrect if either operand side-effects. */
1815 gcc_assert (!TREE_SIDE_EFFECTS (op0)
1816 && !TREE_SIDE_EFFECTS (op1));
1818 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1819 ? LE_EXPR : GE_EXPR),
1820 op0, TREE_CODE (op0),
1821 op1, TREE_CODE (op1),
1822 /*overloaded_p=*/NULL,
1824 cp_build_unary_op (code, op0, 0, complain),
1825 cp_build_unary_op (code, op1, 0, complain),
1830 build_conditional_expr (TREE_OPERAND (t, 0),
1831 cp_build_unary_op (code, TREE_OPERAND (t, 1), 0,
1833 cp_build_unary_op (code, TREE_OPERAND (t, 2), 0,
1838 /* Given the TYPE of an anonymous union field inside T, return the
1839 FIELD_DECL for the field. If not found return NULL_TREE. Because
1840 anonymous unions can nest, we must also search all anonymous unions
1841 that are directly reachable. */
1844 lookup_anon_field (tree t, tree type)
1848 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1850 if (TREE_STATIC (field))
1852 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1855 /* If we find it directly, return the field. */
1856 if (DECL_NAME (field) == NULL_TREE
1857 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1862 /* Otherwise, it could be nested, search harder. */
1863 if (DECL_NAME (field) == NULL_TREE
1864 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1866 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1874 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1875 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1876 non-NULL, it indicates the path to the base used to name MEMBER.
1877 If PRESERVE_REFERENCE is true, the expression returned will have
1878 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1879 returned will have the type referred to by the reference.
1881 This function does not perform access control; that is either done
1882 earlier by the parser when the name of MEMBER is resolved to MEMBER
1883 itself, or later when overload resolution selects one of the
1884 functions indicated by MEMBER. */
1887 build_class_member_access_expr (tree object, tree member,
1888 tree access_path, bool preserve_reference,
1889 tsubst_flags_t complain)
1893 tree result = NULL_TREE;
1895 if (error_operand_p (object) || error_operand_p (member))
1896 return error_mark_node;
1898 gcc_assert (DECL_P (member) || BASELINK_P (member));
1902 The type of the first expression shall be "class object" (of a
1904 object_type = TREE_TYPE (object);
1905 if (!currently_open_class (object_type)
1906 && !complete_type_or_else (object_type, object))
1907 return error_mark_node;
1908 if (!CLASS_TYPE_P (object_type))
1910 if (complain & tf_error)
1911 error ("request for member %qD in %qE, which is of non-class type %qT",
1912 member, object, object_type);
1913 return error_mark_node;
1916 /* The standard does not seem to actually say that MEMBER must be a
1917 member of OBJECT_TYPE. However, that is clearly what is
1919 if (DECL_P (member))
1921 member_scope = DECL_CLASS_CONTEXT (member);
1923 if (TREE_DEPRECATED (member))
1924 warn_deprecated_use (member, NULL_TREE);
1927 member_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (member));
1928 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1929 presently be the anonymous union. Go outwards until we find a
1930 type related to OBJECT_TYPE. */
1931 while (ANON_AGGR_TYPE_P (member_scope)
1932 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1934 member_scope = TYPE_CONTEXT (member_scope);
1935 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1937 if (complain & tf_error)
1939 if (TREE_CODE (member) == FIELD_DECL)
1940 error ("invalid use of nonstatic data member %qE", member);
1942 error ("%qD is not a member of %qT", member, object_type);
1944 return error_mark_node;
1947 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1948 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1949 in the front end; only _DECLs and _REFs are lvalues in the back end. */
1951 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1953 object = cp_build_indirect_ref (temp, NULL, complain);
1956 /* In [expr.ref], there is an explicit list of the valid choices for
1957 MEMBER. We check for each of those cases here. */
1958 if (TREE_CODE (member) == VAR_DECL)
1960 /* A static data member. */
1962 /* If OBJECT has side-effects, they are supposed to occur. */
1963 if (TREE_SIDE_EFFECTS (object))
1964 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1966 else if (TREE_CODE (member) == FIELD_DECL)
1968 /* A non-static data member. */
1973 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1974 && integer_zerop (TREE_OPERAND (object, 0)));
1976 /* Convert OBJECT to the type of MEMBER. */
1977 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1978 TYPE_MAIN_VARIANT (member_scope)))
1983 binfo = lookup_base (access_path ? access_path : object_type,
1984 member_scope, ba_unique, &kind);
1985 if (binfo == error_mark_node)
1986 return error_mark_node;
1988 /* It is invalid to try to get to a virtual base of a
1989 NULL object. The most common cause is invalid use of
1991 if (null_object_p && kind == bk_via_virtual)
1993 if (complain & tf_error)
1995 error ("invalid access to non-static data member %qD of "
1998 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
2000 return error_mark_node;
2003 /* Convert to the base. */
2004 object = build_base_path (PLUS_EXPR, object, binfo,
2006 /* If we found the base successfully then we should be able
2007 to convert to it successfully. */
2008 gcc_assert (object != error_mark_node);
2011 /* Complain about other invalid uses of offsetof, even though they will
2012 give the right answer. Note that we complain whether or not they
2013 actually used the offsetof macro, since there's no way to know at this
2014 point. So we just give a warning, instead of a pedwarn. */
2015 /* Do not produce this warning for base class field references, because
2016 we know for a fact that didn't come from offsetof. This does occur
2017 in various testsuite cases where a null object is passed where a
2018 vtable access is required. */
2019 if (null_object_p && warn_invalid_offsetof
2020 && CLASSTYPE_NON_STD_LAYOUT (object_type)
2021 && !DECL_FIELD_IS_BASE (member)
2022 && cp_unevaluated_operand == 0
2023 && (complain & tf_warning))
2025 warning (OPT_Winvalid_offsetof,
2026 "invalid access to non-static data member %qD "
2027 " of NULL object", member);
2028 warning (OPT_Winvalid_offsetof,
2029 "(perhaps the %<offsetof%> macro was used incorrectly)");
2032 /* If MEMBER is from an anonymous aggregate, we have converted
2033 OBJECT so that it refers to the class containing the
2034 anonymous union. Generate a reference to the anonymous union
2035 itself, and recur to find MEMBER. */
2036 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
2037 /* When this code is called from build_field_call, the
2038 object already has the type of the anonymous union.
2039 That is because the COMPONENT_REF was already
2040 constructed, and was then disassembled before calling
2041 build_field_call. After the function-call code is
2042 cleaned up, this waste can be eliminated. */
2043 && (!same_type_ignoring_top_level_qualifiers_p
2044 (TREE_TYPE (object), DECL_CONTEXT (member))))
2046 tree anonymous_union;
2048 anonymous_union = lookup_anon_field (TREE_TYPE (object),
2049 DECL_CONTEXT (member));
2050 object = build_class_member_access_expr (object,
2052 /*access_path=*/NULL_TREE,
2057 /* Compute the type of the field, as described in [expr.ref]. */
2058 type_quals = TYPE_UNQUALIFIED;
2059 member_type = TREE_TYPE (member);
2060 if (TREE_CODE (member_type) != REFERENCE_TYPE)
2062 type_quals = (cp_type_quals (member_type)
2063 | cp_type_quals (object_type));
2065 /* A field is const (volatile) if the enclosing object, or the
2066 field itself, is const (volatile). But, a mutable field is
2067 not const, even within a const object. */
2068 if (DECL_MUTABLE_P (member))
2069 type_quals &= ~TYPE_QUAL_CONST;
2070 member_type = cp_build_qualified_type (member_type, type_quals);
2073 result = build3 (COMPONENT_REF, member_type, object, member,
2075 result = fold_if_not_in_template (result);
2077 /* Mark the expression const or volatile, as appropriate. Even
2078 though we've dealt with the type above, we still have to mark the
2079 expression itself. */
2080 if (type_quals & TYPE_QUAL_CONST)
2081 TREE_READONLY (result) = 1;
2082 if (type_quals & TYPE_QUAL_VOLATILE)
2083 TREE_THIS_VOLATILE (result) = 1;
2085 else if (BASELINK_P (member))
2087 /* The member is a (possibly overloaded) member function. */
2091 /* If the MEMBER is exactly one static member function, then we
2092 know the type of the expression. Otherwise, we must wait
2093 until overload resolution has been performed. */
2094 functions = BASELINK_FUNCTIONS (member);
2095 if (TREE_CODE (functions) == FUNCTION_DECL
2096 && DECL_STATIC_FUNCTION_P (functions))
2097 type = TREE_TYPE (functions);
2099 type = unknown_type_node;
2100 /* Note that we do not convert OBJECT to the BASELINK_BINFO
2101 base. That will happen when the function is called. */
2102 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
2104 else if (TREE_CODE (member) == CONST_DECL)
2106 /* The member is an enumerator. */
2108 /* If OBJECT has side-effects, they are supposed to occur. */
2109 if (TREE_SIDE_EFFECTS (object))
2110 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2115 if (complain & tf_error)
2116 error ("invalid use of %qD", member);
2117 return error_mark_node;
2120 if (!preserve_reference)
2123 If E2 is declared to have type "reference to T", then ... the
2124 type of E1.E2 is T. */
2125 result = convert_from_reference (result);
2130 /* Return the destructor denoted by OBJECT.SCOPE::DTOR_NAME, or, if
2131 SCOPE is NULL, by OBJECT.DTOR_NAME, where DTOR_NAME is ~type. */
2134 lookup_destructor (tree object, tree scope, tree dtor_name)
2136 tree object_type = TREE_TYPE (object);
2137 tree dtor_type = TREE_OPERAND (dtor_name, 0);
2140 if (scope && !check_dtor_name (scope, dtor_type))
2142 error ("qualified type %qT does not match destructor name ~%qT",
2144 return error_mark_node;
2146 if (TREE_CODE (dtor_type) == IDENTIFIER_NODE)
2148 /* In a template, names we can't find a match for are still accepted
2149 destructor names, and we check them here. */
2150 if (check_dtor_name (object_type, dtor_type))
2151 dtor_type = object_type;
2154 error ("object type %qT does not match destructor name ~%qT",
2155 object_type, dtor_type);
2156 return error_mark_node;
2160 else if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
2162 error ("the type being destroyed is %qT, but the destructor refers to %qT",
2163 TYPE_MAIN_VARIANT (object_type), dtor_type);
2164 return error_mark_node;
2166 expr = lookup_member (dtor_type, complete_dtor_identifier,
2167 /*protect=*/1, /*want_type=*/false);
2168 expr = (adjust_result_of_qualified_name_lookup
2169 (expr, dtor_type, object_type));
2173 /* An expression of the form "A::template B" has been resolved to
2174 DECL. Issue a diagnostic if B is not a template or template
2178 check_template_keyword (tree decl)
2180 /* The standard says:
2184 If a name prefixed by the keyword template is not a member
2185 template, the program is ill-formed.
2187 DR 228 removed the restriction that the template be a member
2190 DR 96, if accepted would add the further restriction that explicit
2191 template arguments must be provided if the template keyword is
2192 used, but, as of 2005-10-16, that DR is still in "drafting". If
2193 this DR is accepted, then the semantic checks here can be
2194 simplified, as the entity named must in fact be a template
2195 specialization, rather than, as at present, a set of overloaded
2196 functions containing at least one template function. */
2197 if (TREE_CODE (decl) != TEMPLATE_DECL
2198 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
2200 if (!is_overloaded_fn (decl))
2201 permerror (input_location, "%qD is not a template", decl);
2206 if (BASELINK_P (fns))
2207 fns = BASELINK_FUNCTIONS (fns);
2210 tree fn = OVL_CURRENT (fns);
2211 if (TREE_CODE (fn) == TEMPLATE_DECL
2212 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2214 if (TREE_CODE (fn) == FUNCTION_DECL
2215 && DECL_USE_TEMPLATE (fn)
2216 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
2218 fns = OVL_NEXT (fns);
2221 permerror (input_location, "%qD is not a template", decl);
2226 /* This function is called by the parser to process a class member
2227 access expression of the form OBJECT.NAME. NAME is a node used by
2228 the parser to represent a name; it is not yet a DECL. It may,
2229 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2230 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2231 there is no reason to do the lookup twice, so the parser keeps the
2232 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2233 be a template via the use of the "A::template B" syntax. */
2236 finish_class_member_access_expr (tree object, tree name, bool template_p,
2237 tsubst_flags_t complain)
2242 tree access_path = NULL_TREE;
2243 tree orig_object = object;
2244 tree orig_name = name;
2246 if (object == error_mark_node || name == error_mark_node)
2247 return error_mark_node;
2249 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2250 if (!objc_is_public (object, name))
2251 return error_mark_node;
2253 object_type = TREE_TYPE (object);
2255 if (processing_template_decl)
2257 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2258 dependent_type_p (object_type)
2259 /* If NAME is just an IDENTIFIER_NODE, then the expression
2261 || TREE_CODE (object) == IDENTIFIER_NODE
2262 /* If NAME is "f<args>", where either 'f' or 'args' is
2263 dependent, then the expression is dependent. */
2264 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2265 && dependent_template_id_p (TREE_OPERAND (name, 0),
2266 TREE_OPERAND (name, 1)))
2267 /* If NAME is "T::X" where "T" is dependent, then the
2268 expression is dependent. */
2269 || (TREE_CODE (name) == SCOPE_REF
2270 && TYPE_P (TREE_OPERAND (name, 0))
2271 && dependent_type_p (TREE_OPERAND (name, 0))))
2272 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2273 object = build_non_dependent_expr (object);
2278 The type of the first expression shall be "class object" (of a
2280 if (!currently_open_class (object_type)
2281 && !complete_type_or_else (object_type, object))
2282 return error_mark_node;
2283 if (!CLASS_TYPE_P (object_type))
2285 if (complain & tf_error)
2286 error ("request for member %qD in %qE, which is of non-class type %qT",
2287 name, object, object_type);
2288 return error_mark_node;
2291 if (BASELINK_P (name))
2292 /* A member function that has already been looked up. */
2296 bool is_template_id = false;
2297 tree template_args = NULL_TREE;
2300 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2302 is_template_id = true;
2303 template_args = TREE_OPERAND (name, 1);
2304 name = TREE_OPERAND (name, 0);
2306 if (TREE_CODE (name) == OVERLOAD)
2307 name = DECL_NAME (get_first_fn (name));
2308 else if (DECL_P (name))
2309 name = DECL_NAME (name);
2312 if (TREE_CODE (name) == SCOPE_REF)
2314 /* A qualified name. The qualifying class or namespace `S'
2315 has already been looked up; it is either a TYPE or a
2317 scope = TREE_OPERAND (name, 0);
2318 name = TREE_OPERAND (name, 1);
2320 /* If SCOPE is a namespace, then the qualified name does not
2321 name a member of OBJECT_TYPE. */
2322 if (TREE_CODE (scope) == NAMESPACE_DECL)
2324 if (complain & tf_error)
2325 error ("%<%D::%D%> is not a member of %qT",
2326 scope, name, object_type);
2327 return error_mark_node;
2330 gcc_assert (CLASS_TYPE_P (scope));
2331 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2332 || TREE_CODE (name) == BIT_NOT_EXPR);
2334 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2335 access_path = lookup_base (object_type, scope, ba_check, NULL);
2336 if (access_path == error_mark_node)
2337 return error_mark_node;
2340 if (complain & tf_error)
2341 error ("%qT is not a base of %qT", scope, object_type);
2342 return error_mark_node;
2348 access_path = object_type;
2351 if (TREE_CODE (name) == BIT_NOT_EXPR)
2352 member = lookup_destructor (object, scope, name);
2355 /* Look up the member. */
2356 member = lookup_member (access_path, name, /*protect=*/1,
2357 /*want_type=*/false);
2358 if (member == NULL_TREE)
2360 if (complain & tf_error)
2361 error ("%qD has no member named %qE", object_type, name);
2362 return error_mark_node;
2364 if (member == error_mark_node)
2365 return error_mark_node;
2370 tree templ = member;
2372 if (BASELINK_P (templ))
2373 templ = lookup_template_function (templ, template_args);
2376 if (complain & tf_error)
2377 error ("%qD is not a member template function", name);
2378 return error_mark_node;
2383 if (TREE_DEPRECATED (member))
2384 warn_deprecated_use (member, NULL_TREE);
2387 check_template_keyword (member);
2389 expr = build_class_member_access_expr (object, member, access_path,
2390 /*preserve_reference=*/false,
2392 if (processing_template_decl && expr != error_mark_node)
2394 if (BASELINK_P (member))
2396 if (TREE_CODE (orig_name) == SCOPE_REF)
2397 BASELINK_QUALIFIED_P (member) = 1;
2400 return build_min_non_dep (COMPONENT_REF, expr,
2401 orig_object, orig_name,
2408 /* Return an expression for the MEMBER_NAME field in the internal
2409 representation of PTRMEM, a pointer-to-member function. (Each
2410 pointer-to-member function type gets its own RECORD_TYPE so it is
2411 more convenient to access the fields by name than by FIELD_DECL.)
2412 This routine converts the NAME to a FIELD_DECL and then creates the
2413 node for the complete expression. */
2416 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2422 /* This code is a stripped down version of
2423 build_class_member_access_expr. It does not work to use that
2424 routine directly because it expects the object to be of class
2426 ptrmem_type = TREE_TYPE (ptrmem);
2427 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2428 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2429 /*want_type=*/false);
2430 member_type = cp_build_qualified_type (TREE_TYPE (member),
2431 cp_type_quals (ptrmem_type));
2432 return fold_build3_loc (input_location,
2433 COMPONENT_REF, member_type,
2434 ptrmem, member, NULL_TREE);
2437 /* Given an expression PTR for a pointer, return an expression
2438 for the value pointed to.
2439 ERRORSTRING is the name of the operator to appear in error messages.
2441 This function may need to overload OPERATOR_FNNAME.
2442 Must also handle REFERENCE_TYPEs for C++. */
2445 build_x_indirect_ref (tree expr, const char *errorstring,
2446 tsubst_flags_t complain)
2448 tree orig_expr = expr;
2451 if (processing_template_decl)
2453 /* Retain the type if we know the operand is a pointer so that
2454 describable_type doesn't make auto deduction break. */
2455 if (TREE_TYPE (expr) && POINTER_TYPE_P (TREE_TYPE (expr)))
2456 return build_min (INDIRECT_REF, TREE_TYPE (TREE_TYPE (expr)), expr);
2457 if (type_dependent_expression_p (expr))
2458 return build_min_nt (INDIRECT_REF, expr);
2459 expr = build_non_dependent_expr (expr);
2462 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2463 NULL_TREE, /*overloaded_p=*/NULL, complain);
2465 rval = cp_build_indirect_ref (expr, errorstring, complain);
2467 if (processing_template_decl && rval != error_mark_node)
2468 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2473 /* Helper function called from c-common. */
2475 build_indirect_ref (location_t loc __attribute__ ((__unused__)),
2476 tree ptr, const char *errorstring)
2478 return cp_build_indirect_ref (ptr, errorstring, tf_warning_or_error);
2482 cp_build_indirect_ref (tree ptr, const char *errorstring,
2483 tsubst_flags_t complain)
2487 if (ptr == error_mark_node)
2488 return error_mark_node;
2490 if (ptr == current_class_ptr)
2491 return current_class_ref;
2493 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2494 ? ptr : decay_conversion (ptr));
2495 type = TREE_TYPE (pointer);
2497 if (POINTER_TYPE_P (type))
2501 If the type of the expression is "pointer to T," the type
2502 of the result is "T." */
2503 tree t = TREE_TYPE (type);
2505 if (CONVERT_EXPR_P (ptr)
2506 || TREE_CODE (ptr) == VIEW_CONVERT_EXPR)
2508 /* If a warning is issued, mark it to avoid duplicates from
2509 the backend. This only needs to be done at
2510 warn_strict_aliasing > 2. */
2511 if (warn_strict_aliasing > 2)
2512 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (ptr, 0)),
2513 type, TREE_OPERAND (ptr, 0)))
2514 TREE_NO_WARNING (ptr) = 1;
2517 if (VOID_TYPE_P (t))
2519 /* A pointer to incomplete type (other than cv void) can be
2520 dereferenced [expr.unary.op]/1 */
2521 if (complain & tf_error)
2522 error ("%qT is not a pointer-to-object type", type);
2523 return error_mark_node;
2525 else if (TREE_CODE (pointer) == ADDR_EXPR
2526 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2527 /* The POINTER was something like `&x'. We simplify `*&x' to
2529 return TREE_OPERAND (pointer, 0);
2532 tree ref = build1 (INDIRECT_REF, t, pointer);
2534 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2535 so that we get the proper error message if the result is used
2536 to assign to. Also, &* is supposed to be a no-op. */
2537 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2538 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2539 TREE_SIDE_EFFECTS (ref)
2540 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2544 else if (!(complain & tf_error))
2545 /* Don't emit any errors; we'll just return ERROR_MARK_NODE later. */
2547 /* `pointer' won't be an error_mark_node if we were given a
2548 pointer to member, so it's cool to check for this here. */
2549 else if (TYPE_PTR_TO_MEMBER_P (type))
2550 error ("invalid use of %qs on pointer to member", errorstring);
2551 else if (pointer != error_mark_node)
2554 error ("invalid type argument of %qs", errorstring);
2556 error ("invalid type argument");
2558 return error_mark_node;
2561 /* This handles expressions of the form "a[i]", which denotes
2564 This is logically equivalent in C to *(a+i), but we may do it differently.
2565 If A is a variable or a member, we generate a primitive ARRAY_REF.
2566 This avoids forcing the array out of registers, and can work on
2567 arrays that are not lvalues (for example, members of structures returned
2570 If INDEX is of some user-defined type, it must be converted to
2571 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2572 will inherit the type of the array, which will be some pointer type.
2574 LOC is the location to use in building the array reference. */
2577 build_array_ref (location_t loc, tree array, tree idx)
2583 error_at (loc, "subscript missing in array reference");
2584 return error_mark_node;
2587 if (TREE_TYPE (array) == error_mark_node
2588 || TREE_TYPE (idx) == error_mark_node)
2589 return error_mark_node;
2591 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2593 switch (TREE_CODE (array))
2597 tree value = build_array_ref (loc, TREE_OPERAND (array, 1), idx);
2598 ret = build2 (COMPOUND_EXPR, TREE_TYPE (value),
2599 TREE_OPERAND (array, 0), value);
2600 SET_EXPR_LOCATION (ret, loc);
2605 ret = build_conditional_expr
2606 (TREE_OPERAND (array, 0),
2607 build_array_ref (loc, TREE_OPERAND (array, 1), idx),
2608 build_array_ref (loc, TREE_OPERAND (array, 2), idx),
2609 tf_warning_or_error);
2610 protected_set_expr_location (ret, loc);
2617 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2621 warn_array_subscript_with_type_char (idx);
2623 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2625 error_at (loc, "array subscript is not an integer");
2626 return error_mark_node;
2629 /* Apply integral promotions *after* noticing character types.
2630 (It is unclear why we do these promotions -- the standard
2631 does not say that we should. In fact, the natural thing would
2632 seem to be to convert IDX to ptrdiff_t; we're performing
2633 pointer arithmetic.) */
2634 idx = perform_integral_promotions (idx);
2636 /* An array that is indexed by a non-constant
2637 cannot be stored in a register; we must be able to do
2638 address arithmetic on its address.
2639 Likewise an array of elements of variable size. */
2640 if (TREE_CODE (idx) != INTEGER_CST
2641 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2642 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2645 if (!cxx_mark_addressable (array))
2646 return error_mark_node;
2649 /* An array that is indexed by a constant value which is not within
2650 the array bounds cannot be stored in a register either; because we
2651 would get a crash in store_bit_field/extract_bit_field when trying
2652 to access a non-existent part of the register. */
2653 if (TREE_CODE (idx) == INTEGER_CST
2654 && TYPE_DOMAIN (TREE_TYPE (array))
2655 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2657 if (!cxx_mark_addressable (array))
2658 return error_mark_node;
2661 if (!lvalue_p (array))
2662 pedwarn (loc, OPT_pedantic,
2663 "ISO C++ forbids subscripting non-lvalue array");
2665 /* Note in C++ it is valid to subscript a `register' array, since
2666 it is valid to take the address of something with that
2667 storage specification. */
2671 while (TREE_CODE (foo) == COMPONENT_REF)
2672 foo = TREE_OPERAND (foo, 0);
2673 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2674 warning_at (loc, OPT_Wextra,
2675 "subscripting array declared %<register%>");
2678 type = TREE_TYPE (TREE_TYPE (array));
2679 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2680 /* Array ref is const/volatile if the array elements are
2681 or if the array is.. */
2682 TREE_READONLY (rval)
2683 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2684 TREE_SIDE_EFFECTS (rval)
2685 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2686 TREE_THIS_VOLATILE (rval)
2687 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2688 ret = require_complete_type (fold_if_not_in_template (rval));
2689 protected_set_expr_location (ret, loc);
2694 tree ar = default_conversion (array);
2695 tree ind = default_conversion (idx);
2697 /* Put the integer in IND to simplify error checking. */
2698 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2705 if (ar == error_mark_node)
2708 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2710 error_at (loc, "subscripted value is neither array nor pointer");
2711 return error_mark_node;
2713 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2715 error_at (loc, "array subscript is not an integer");
2716 return error_mark_node;
2719 warn_array_subscript_with_type_char (idx);
2721 ret = cp_build_indirect_ref (cp_build_binary_op (input_location,
2723 tf_warning_or_error),
2725 tf_warning_or_error);
2726 protected_set_expr_location (ret, loc);
2731 /* Resolve a pointer to member function. INSTANCE is the object
2732 instance to use, if the member points to a virtual member.
2734 This used to avoid checking for virtual functions if basetype
2735 has no virtual functions, according to an earlier ANSI draft.
2736 With the final ISO C++ rules, such an optimization is
2737 incorrect: A pointer to a derived member can be static_cast
2738 to pointer-to-base-member, as long as the dynamic object
2739 later has the right member. */
2742 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2744 if (TREE_CODE (function) == OFFSET_REF)
2745 function = TREE_OPERAND (function, 1);
2747 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2749 tree idx, delta, e1, e2, e3, vtbl, basetype;
2750 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2752 tree instance_ptr = *instance_ptrptr;
2753 tree instance_save_expr = 0;
2754 if (instance_ptr == error_mark_node)
2756 if (TREE_CODE (function) == PTRMEM_CST)
2758 /* Extracting the function address from a pmf is only
2759 allowed with -Wno-pmf-conversions. It only works for
2761 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2762 e1 = convert (fntype, e1);
2767 error ("object missing in use of %qE", function);
2768 return error_mark_node;
2772 if (TREE_SIDE_EFFECTS (instance_ptr))
2773 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2775 if (TREE_SIDE_EFFECTS (function))
2776 function = save_expr (function);
2778 /* Start by extracting all the information from the PMF itself. */
2779 e3 = pfn_from_ptrmemfunc (function);
2780 delta = delta_from_ptrmemfunc (function);
2781 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2782 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2784 case ptrmemfunc_vbit_in_pfn:
2785 e1 = cp_build_binary_op (input_location,
2786 BIT_AND_EXPR, idx, integer_one_node,
2787 tf_warning_or_error);
2788 idx = cp_build_binary_op (input_location,
2789 MINUS_EXPR, idx, integer_one_node,
2790 tf_warning_or_error);
2793 case ptrmemfunc_vbit_in_delta:
2794 e1 = cp_build_binary_op (input_location,
2795 BIT_AND_EXPR, delta, integer_one_node,
2796 tf_warning_or_error);
2797 delta = cp_build_binary_op (input_location,
2798 RSHIFT_EXPR, delta, integer_one_node,
2799 tf_warning_or_error);
2806 /* Convert down to the right base before using the instance. A
2807 special case is that in a pointer to member of class C, C may
2808 be incomplete. In that case, the function will of course be
2809 a member of C, and no conversion is required. In fact,
2810 lookup_base will fail in that case, because incomplete
2811 classes do not have BINFOs. */
2812 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2813 if (!same_type_ignoring_top_level_qualifiers_p
2814 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2816 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2817 basetype, ba_check, NULL);
2818 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2820 if (instance_ptr == error_mark_node)
2821 return error_mark_node;
2823 /* ...and then the delta in the PMF. */
2824 instance_ptr = build2 (POINTER_PLUS_EXPR, TREE_TYPE (instance_ptr),
2825 instance_ptr, fold_convert (sizetype, delta));
2827 /* Hand back the adjusted 'this' argument to our caller. */
2828 *instance_ptrptr = instance_ptr;
2830 /* Next extract the vtable pointer from the object. */
2831 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2833 vtbl = cp_build_indirect_ref (vtbl, NULL, tf_warning_or_error);
2834 /* If the object is not dynamic the access invokes undefined
2835 behavior. As it is not executed in this case silence the
2836 spurious warnings it may provoke. */
2837 TREE_NO_WARNING (vtbl) = 1;
2839 /* Finally, extract the function pointer from the vtable. */
2840 e2 = fold_build2_loc (input_location,
2841 POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl,
2842 fold_convert (sizetype, idx));
2843 e2 = cp_build_indirect_ref (e2, NULL, tf_warning_or_error);
2844 TREE_CONSTANT (e2) = 1;
2846 /* When using function descriptors, the address of the
2847 vtable entry is treated as a function pointer. */
2848 if (TARGET_VTABLE_USES_DESCRIPTORS)
2849 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2850 cp_build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1,
2851 tf_warning_or_error));
2853 e2 = fold_convert (TREE_TYPE (e3), e2);
2854 e1 = build_conditional_expr (e1, e2, e3, tf_warning_or_error);
2856 /* Make sure this doesn't get evaluated first inside one of the
2857 branches of the COND_EXPR. */
2858 if (instance_save_expr)
2859 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2860 instance_save_expr, e1);
2867 /* Used by the C-common bits. */
2869 build_function_call (location_t loc ATTRIBUTE_UNUSED,
2870 tree function, tree params)
2872 return cp_build_function_call (function, params, tf_warning_or_error);
2875 /* Used by the C-common bits. */
2877 build_function_call_vec (location_t loc ATTRIBUTE_UNUSED,
2878 tree function, VEC(tree,gc) *params,
2879 VEC(tree,gc) *origtypes ATTRIBUTE_UNUSED)
2881 VEC(tree,gc) *orig_params = params;
2882 tree ret = cp_build_function_call_vec (function, ¶ms,
2883 tf_warning_or_error);
2885 /* cp_build_function_call_vec can reallocate PARAMS by adding
2886 default arguments. That should never happen here. Verify
2888 gcc_assert (params == orig_params);
2893 /* Build a function call using a tree list of arguments. */
2896 cp_build_function_call (tree function, tree params, tsubst_flags_t complain)
2901 vec = make_tree_vector ();
2902 for (; params != NULL_TREE; params = TREE_CHAIN (params))
2903 VEC_safe_push (tree, gc, vec, TREE_VALUE (params));
2904 ret = cp_build_function_call_vec (function, &vec, complain);
2905 release_tree_vector (vec);
2909 /* Build a function call using a vector of arguments. PARAMS may be
2910 NULL if there are no parameters. This changes the contents of
2914 cp_build_function_call_vec (tree function, VEC(tree,gc) **params,
2915 tsubst_flags_t complain)
2917 tree fntype, fndecl;
2918 tree name = NULL_TREE;
2920 tree original = function;
2924 VEC(tree,gc) *allocated = NULL;
2927 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2928 expressions, like those used for ObjC messenger dispatches. */
2929 if (params != NULL && !VEC_empty (tree, *params))
2930 function = objc_rewrite_function_call (function,
2931 VEC_index (tree, *params, 0));
2933 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2934 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2935 if (TREE_CODE (function) == NOP_EXPR
2936 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2937 function = TREE_OPERAND (function, 0);
2939 if (TREE_CODE (function) == FUNCTION_DECL)
2941 name = DECL_NAME (function);
2943 mark_used (function);
2946 /* Convert anything with function type to a pointer-to-function. */
2947 if (DECL_MAIN_P (function) && (complain & tf_error))
2948 pedwarn (input_location, OPT_pedantic,
2949 "ISO C++ forbids calling %<::main%> from within program");
2951 function = build_addr_func (function);
2957 function = build_addr_func (function);
2960 if (function == error_mark_node)
2961 return error_mark_node;
2963 fntype = TREE_TYPE (function);
2965 if (TYPE_PTRMEMFUNC_P (fntype))
2967 if (complain & tf_error)
2968 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2969 "function in %<%E (...)%>, e.g. %<(... ->* %E) (...)%>",
2970 original, original);
2971 return error_mark_node;
2974 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2975 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2977 if (!((TREE_CODE (fntype) == POINTER_TYPE
2978 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2980 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2982 if (complain & tf_error)
2983 error ("%qE cannot be used as a function", original);
2984 return error_mark_node;
2987 /* fntype now gets the type of function pointed to. */
2988 fntype = TREE_TYPE (fntype);
2989 parm_types = TYPE_ARG_TYPES (fntype);
2993 allocated = make_tree_vector ();
2994 params = &allocated;
2997 nargs = convert_arguments (parm_types, params, fndecl, LOOKUP_NORMAL,
3000 return error_mark_node;
3002 argarray = VEC_address (tree, *params);
3004 /* Check for errors in format strings and inappropriately
3006 check_function_arguments (TYPE_ATTRIBUTES (fntype), nargs, argarray,
3009 ret = build_cxx_call (function, nargs, argarray);
3011 if (allocated != NULL)
3012 release_tree_vector (allocated);
3017 /* Convert the actual parameter expressions in the list VALUES to the
3018 types in the list TYPELIST. The converted expressions are stored
3019 back in the VALUES vector.
3020 If parmdecls is exhausted, or when an element has NULL as its type,
3021 perform the default conversions.
3023 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
3025 This is also where warnings about wrong number of args are generated.
3027 Returns the actual number of arguments processed (which might be less
3028 than the length of the vector), or -1 on error.
3030 In C++, unspecified trailing parameters can be filled in with their
3031 default arguments, if such were specified. Do so here. */
3034 convert_arguments (tree typelist, VEC(tree,gc) **values, tree fndecl,
3035 int flags, tsubst_flags_t complain)
3038 const char *called_thing = 0;
3041 /* Argument passing is always copy-initialization. */
3042 flags |= LOOKUP_ONLYCONVERTING;
3046 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
3048 if (DECL_NAME (fndecl) == NULL_TREE
3049 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
3050 called_thing = "constructor";
3052 called_thing = "member function";
3055 called_thing = "function";
3058 for (i = 0, typetail = typelist;
3059 i < VEC_length (tree, *values);
3062 tree type = typetail ? TREE_VALUE (typetail) : 0;
3063 tree val = VEC_index (tree, *values, i);
3065 if (val == error_mark_node || type == error_mark_node)
3068 if (type == void_type_node)
3070 if (complain & tf_error)
3074 error ("too many arguments to %s %q+#D",
3075 called_thing, fndecl);
3076 error ("at this point in file");
3079 error ("too many arguments to function");
3086 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3087 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
3088 if (TREE_CODE (val) == NOP_EXPR
3089 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
3090 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
3091 val = TREE_OPERAND (val, 0);
3093 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
3095 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
3096 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
3097 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
3098 val = decay_conversion (val);
3101 if (val == error_mark_node)
3106 /* Formal parm type is specified by a function prototype. */
3109 if (!COMPLETE_TYPE_P (complete_type (type)))
3111 if (complain & tf_error)
3114 error ("parameter %P of %qD has incomplete type %qT",
3117 error ("parameter %P has incomplete type %qT", i, type);
3119 parmval = error_mark_node;
3123 parmval = convert_for_initialization
3124 (NULL_TREE, type, val, flags,
3125 "argument passing", fndecl, i, complain);
3126 parmval = convert_for_arg_passing (type, parmval);
3129 if (parmval == error_mark_node)
3132 VEC_replace (tree, *values, i, parmval);
3136 if (fndecl && DECL_BUILT_IN (fndecl)
3137 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
3138 /* Don't do ellipsis conversion for __built_in_constant_p
3139 as this will result in spurious errors for non-trivial
3141 val = require_complete_type (val);
3143 val = convert_arg_to_ellipsis (val);
3145 VEC_replace (tree, *values, i, val);
3149 typetail = TREE_CHAIN (typetail);
3152 if (typetail != 0 && typetail != void_list_node)
3154 /* See if there are default arguments that can be used. Because
3155 we hold default arguments in the FUNCTION_TYPE (which is so
3156 wrong), we can see default parameters here from deduced
3157 contexts (and via typeof) for indirect function calls.
3158 Fortunately we know whether we have a function decl to
3159 provide default arguments in a language conformant
3161 if (fndecl && TREE_PURPOSE (typetail)
3162 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
3164 for (; typetail != void_list_node; ++i)
3167 = convert_default_arg (TREE_VALUE (typetail),
3168 TREE_PURPOSE (typetail),
3171 if (parmval == error_mark_node)
3174 VEC_safe_push (tree, gc, *values, parmval);
3175 typetail = TREE_CHAIN (typetail);
3176 /* ends with `...'. */
3177 if (typetail == NULL_TREE)
3183 if (complain & tf_error)
3187 error ("too few arguments to %s %q+#D",
3188 called_thing, fndecl);
3189 error ("at this point in file");
3192 error ("too few arguments to function");
3201 /* Build a binary-operation expression, after performing default
3202 conversions on the operands. CODE is the kind of expression to
3203 build. ARG1 and ARG2 are the arguments. ARG1_CODE and ARG2_CODE
3204 are the tree codes which correspond to ARG1 and ARG2 when issuing
3205 warnings about possibly misplaced parentheses. They may differ
3206 from the TREE_CODE of ARG1 and ARG2 if the parser has done constant
3207 folding (e.g., if the parser sees "a | 1 + 1", it may call this
3208 routine with ARG2 being an INTEGER_CST and ARG2_CODE == PLUS_EXPR).
3209 To avoid issuing any parentheses warnings, pass ARG1_CODE and/or
3210 ARG2_CODE as ERROR_MARK. */
3213 build_x_binary_op (enum tree_code code, tree arg1, enum tree_code arg1_code,
3214 tree arg2, enum tree_code arg2_code, bool *overloaded_p,
3215 tsubst_flags_t complain)
3224 if (processing_template_decl)
3226 if (type_dependent_expression_p (arg1)
3227 || type_dependent_expression_p (arg2))
3228 return build_min_nt (code, arg1, arg2);
3229 arg1 = build_non_dependent_expr (arg1);
3230 arg2 = build_non_dependent_expr (arg2);
3233 if (code == DOTSTAR_EXPR)
3234 expr = build_m_component_ref (arg1, arg2);
3236 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3237 overloaded_p, complain);
3239 /* Check for cases such as x+y<<z which users are likely to
3240 misinterpret. But don't warn about obj << x + y, since that is a
3241 common idiom for I/O. */
3242 if (warn_parentheses
3243 && !processing_template_decl
3244 && !error_operand_p (arg1)
3245 && !error_operand_p (arg2)
3246 && (code != LSHIFT_EXPR
3247 || !CLASS_TYPE_P (TREE_TYPE (arg1))))
3248 warn_about_parentheses (code, arg1_code, orig_arg1, arg2_code, orig_arg2);
3250 if (processing_template_decl && expr != error_mark_node)
3251 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
3256 /* Build and return an ARRAY_REF expression. */
3259 build_x_array_ref (tree arg1, tree arg2, tsubst_flags_t complain)
3261 tree orig_arg1 = arg1;
3262 tree orig_arg2 = arg2;
3265 if (processing_template_decl)
3267 if (type_dependent_expression_p (arg1)
3268 || type_dependent_expression_p (arg2))
3269 return build_min_nt (ARRAY_REF, arg1, arg2,
3270 NULL_TREE, NULL_TREE);
3271 arg1 = build_non_dependent_expr (arg1);
3272 arg2 = build_non_dependent_expr (arg2);
3275 expr = build_new_op (ARRAY_REF, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3276 /*overloaded_p=*/NULL, complain);
3278 if (processing_template_decl && expr != error_mark_node)
3279 return build_min_non_dep (ARRAY_REF, expr, orig_arg1, orig_arg2,
3280 NULL_TREE, NULL_TREE);
3284 /* For the c-common bits. */
3286 build_binary_op (location_t location, enum tree_code code, tree op0, tree op1,
3287 int convert_p ATTRIBUTE_UNUSED)
3289 return cp_build_binary_op (location, code, op0, op1, tf_warning_or_error);
3293 /* Build a binary-operation expression without default conversions.
3294 CODE is the kind of expression to build.
3295 LOCATION is the location_t of the operator in the source code.
3296 This function differs from `build' in several ways:
3297 the data type of the result is computed and recorded in it,
3298 warnings are generated if arg data types are invalid,
3299 special handling for addition and subtraction of pointers is known,
3300 and some optimization is done (operations on narrow ints
3301 are done in the narrower type when that gives the same result).
3302 Constant folding is also done before the result is returned.
3304 Note that the operands will never have enumeral types
3305 because either they have just had the default conversions performed
3306 or they have both just been converted to some other type in which
3307 the arithmetic is to be done.
3309 C++: must do special pointer arithmetic when implementing
3310 multiple inheritance, and deal with pointer to member functions. */
3313 cp_build_binary_op (location_t location,
3314 enum tree_code code, tree orig_op0, tree orig_op1,
3315 tsubst_flags_t complain)
3318 enum tree_code code0, code1;
3320 const char *invalid_op_diag;
3322 /* Expression code to give to the expression when it is built.
3323 Normally this is CODE, which is what the caller asked for,
3324 but in some special cases we change it. */
3325 enum tree_code resultcode = code;
3327 /* Data type in which the computation is to be performed.
3328 In the simplest cases this is the common type of the arguments. */
3329 tree result_type = NULL;
3331 /* Nonzero means operands have already been type-converted
3332 in whatever way is necessary.
3333 Zero means they need to be converted to RESULT_TYPE. */
3336 /* Nonzero means create the expression with this type, rather than
3338 tree build_type = 0;
3340 /* Nonzero means after finally constructing the expression
3341 convert it to this type. */
3342 tree final_type = 0;
3346 /* Nonzero if this is an operation like MIN or MAX which can
3347 safely be computed in short if both args are promoted shorts.
3348 Also implies COMMON.
3349 -1 indicates a bitwise operation; this makes a difference
3350 in the exact conditions for when it is safe to do the operation
3351 in a narrower mode. */
3354 /* Nonzero if this is a comparison operation;
3355 if both args are promoted shorts, compare the original shorts.
3356 Also implies COMMON. */
3357 int short_compare = 0;
3359 /* Nonzero means set RESULT_TYPE to the common type of the args. */
3362 /* True if both operands have arithmetic type. */
3363 bool arithmetic_types_p;
3365 /* Apply default conversions. */
3369 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
3370 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
3371 || code == TRUTH_XOR_EXPR)
3373 if (!really_overloaded_fn (op0))
3374 op0 = decay_conversion (op0);
3375 if (!really_overloaded_fn (op1))
3376 op1 = decay_conversion (op1);
3380 if (!really_overloaded_fn (op0))
3381 op0 = default_conversion (op0);
3382 if (!really_overloaded_fn (op1))
3383 op1 = default_conversion (op1);
3386 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3387 STRIP_TYPE_NOPS (op0);
3388 STRIP_TYPE_NOPS (op1);
3390 /* DTRT if one side is an overloaded function, but complain about it. */
3391 if (type_unknown_p (op0))
3393 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3394 if (t != error_mark_node)
3396 if (complain & tf_error)
3397 permerror (input_location, "assuming cast to type %qT from overloaded function",
3402 if (type_unknown_p (op1))
3404 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3405 if (t != error_mark_node)
3407 if (complain & tf_error)
3408 permerror (input_location, "assuming cast to type %qT from overloaded function",
3414 type0 = TREE_TYPE (op0);
3415 type1 = TREE_TYPE (op1);
3417 /* The expression codes of the data types of the arguments tell us
3418 whether the arguments are integers, floating, pointers, etc. */
3419 code0 = TREE_CODE (type0);
3420 code1 = TREE_CODE (type1);
3422 /* If an error was already reported for one of the arguments,
3423 avoid reporting another error. */
3424 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3425 return error_mark_node;
3427 if ((invalid_op_diag
3428 = targetm.invalid_binary_op (code, type0, type1)))
3430 error (invalid_op_diag);
3431 return error_mark_node;
3434 /* Issue warnings about peculiar, but valid, uses of NULL. */
3435 if ((orig_op0 == null_node || orig_op1 == null_node)
3436 /* It's reasonable to use pointer values as operands of &&
3437 and ||, so NULL is no exception. */
3438 && code != TRUTH_ANDIF_EXPR && code != TRUTH_ORIF_EXPR
3439 && ( /* Both are NULL (or 0) and the operation was not a
3440 comparison or a pointer subtraction. */
3441 (null_ptr_cst_p (orig_op0) && null_ptr_cst_p (orig_op1)
3442 && code != EQ_EXPR && code != NE_EXPR && code != MINUS_EXPR)
3443 /* Or if one of OP0 or OP1 is neither a pointer nor NULL. */
3444 || (!null_ptr_cst_p (orig_op0)
3445 && !TYPE_PTR_P (type0) && !TYPE_PTR_TO_MEMBER_P (type0))
3446 || (!null_ptr_cst_p (orig_op1)
3447 && !TYPE_PTR_P (type1) && !TYPE_PTR_TO_MEMBER_P (type1)))
3448 && (complain & tf_warning))
3449 /* Some sort of arithmetic operation involving NULL was
3451 warning (OPT_Wpointer_arith, "NULL used in arithmetic");
3456 /* Subtraction of two similar pointers.
3457 We must subtract them as integers, then divide by object size. */
3458 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3459 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3461 return pointer_diff (op0, op1, common_pointer_type (type0, type1));
3462 /* In all other cases except pointer - int, the usual arithmetic
3464 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
3469 /* The pointer - int case is just like pointer + int; fall
3472 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
3473 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
3477 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
3478 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
3479 if (processing_template_decl)
3481 result_type = TREE_TYPE (ptr_operand);
3484 return cp_pointer_int_sum (code,
3495 case TRUNC_DIV_EXPR:
3497 case FLOOR_DIV_EXPR:
3498 case ROUND_DIV_EXPR:
3499 case EXACT_DIV_EXPR:
3500 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3501 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3502 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3503 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3505 enum tree_code tcode0 = code0, tcode1 = code1;
3507 warn_for_div_by_zero (location, op1);
3509 if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE)
3510 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3511 if (tcode1 == COMPLEX_TYPE || tcode1 == VECTOR_TYPE)
3512 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3514 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
3515 resultcode = RDIV_EXPR;
3517 /* When dividing two signed integers, we have to promote to int.
3518 unless we divide by a constant != -1. Note that default
3519 conversion will have been performed on the operands at this
3520 point, so we have to dig out the original type to find out if
3522 shorten = ((TREE_CODE (op0) == NOP_EXPR
3523 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3524 || (TREE_CODE (op1) == INTEGER_CST
3525 && ! integer_all_onesp (op1)));
3534 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3535 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3536 && !VECTOR_FLOAT_TYPE_P (type0)
3537 && !VECTOR_FLOAT_TYPE_P (type1)))
3541 case TRUNC_MOD_EXPR:
3542 case FLOOR_MOD_EXPR:
3543 warn_for_div_by_zero (location, op1);
3545 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3546 && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE
3547 && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE)
3549 else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3551 /* Although it would be tempting to shorten always here, that loses
3552 on some targets, since the modulo instruction is undefined if the
3553 quotient can't be represented in the computation mode. We shorten
3554 only if unsigned or if dividing by something we know != -1. */
3555 shorten = ((TREE_CODE (op0) == NOP_EXPR
3556 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3557 || (TREE_CODE (op1) == INTEGER_CST
3558 && ! integer_all_onesp (op1)));
3563 case TRUTH_ANDIF_EXPR:
3564 case TRUTH_ORIF_EXPR:
3565 case TRUTH_AND_EXPR:
3567 result_type = boolean_type_node;
3570 /* Shift operations: result has same type as first operand;
3571 always convert second operand to int.
3572 Also set SHORT_SHIFT if shifting rightward. */
3575 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3577 result_type = type0;
3578 if (TREE_CODE (op1) == INTEGER_CST)
3580 if (tree_int_cst_lt (op1, integer_zero_node))
3582 if ((complain & tf_warning)
3583 && c_inhibit_evaluation_warnings == 0)
3584 warning (0, "right shift count is negative");
3588 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0
3589 && (complain & tf_warning)
3590 && c_inhibit_evaluation_warnings == 0)
3591 warning (0, "right shift count >= width of type");
3594 /* Convert the shift-count to an integer, regardless of
3595 size of value being shifted. */
3596 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3597 op1 = cp_convert (integer_type_node, op1);
3598 /* Avoid converting op1 to result_type later. */
3604 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3606 result_type = type0;
3607 if (TREE_CODE (op1) == INTEGER_CST)
3609 if (tree_int_cst_lt (op1, integer_zero_node))
3611 if ((complain & tf_warning)
3612 && c_inhibit_evaluation_warnings == 0)
3613 warning (0, "left shift count is negative");
3615 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3617 if ((complain & tf_warning)
3618 && c_inhibit_evaluation_warnings == 0)
3619 warning (0, "left shift count >= width of type");
3622 /* Convert the shift-count to an integer, regardless of
3623 size of value being shifted. */
3624 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3625 op1 = cp_convert (integer_type_node, op1);
3626 /* Avoid converting op1 to result_type later. */
3633 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3635 result_type = type0;
3636 if (TREE_CODE (op1) == INTEGER_CST)
3638 if (tree_int_cst_lt (op1, integer_zero_node))
3640 if (complain & tf_warning)
3641 warning (0, (code == LROTATE_EXPR)
3642 ? G_("left rotate count is negative")
3643 : G_("right rotate count is negative"));
3645 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3647 if (complain & tf_warning)
3648 warning (0, (code == LROTATE_EXPR)
3649 ? G_("left rotate count >= width of type")
3650 : G_("right rotate count >= width of type"));
3653 /* Convert the shift-count to an integer, regardless of
3654 size of value being shifted. */
3655 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3656 op1 = cp_convert (integer_type_node, op1);
3662 if ((complain & tf_warning)
3663 && (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1)))
3664 warning (OPT_Wfloat_equal,
3665 "comparing floating point with == or != is unsafe");
3666 if ((complain & tf_warning)
3667 && ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3668 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0))))
3669 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3671 build_type = boolean_type_node;
3672 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3673 || code0 == COMPLEX_TYPE || code0 == ENUMERAL_TYPE)
3674 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3675 || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE))
3677 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3678 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3679 result_type = composite_pointer_type (type0, type1, op0, op1,
3680 "comparison", complain);
3681 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3682 && null_ptr_cst_p (op1))
3684 if (TREE_CODE (op0) == ADDR_EXPR
3685 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
3687 if (complain & tf_warning)
3688 warning (OPT_Waddress, "the address of %qD will never be NULL",
3689 TREE_OPERAND (op0, 0));
3691 result_type = type0;
3693 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3694 && null_ptr_cst_p (op0))
3696 if (TREE_CODE (op1) == ADDR_EXPR
3697 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
3699 if (complain & tf_warning)
3700 warning (OPT_Waddress, "the address of %qD will never be NULL",
3701 TREE_OPERAND (op1, 0));
3703 result_type = type1;
3705 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3707 result_type = type0;
3708 if (complain & tf_error)
3709 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3711 return error_mark_node;
3713 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3715 result_type = type1;
3716 if (complain & tf_error)
3717 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3719 return error_mark_node;
3721 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3723 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3724 == ptrmemfunc_vbit_in_delta)
3726 tree pfn0 = pfn_from_ptrmemfunc (op0);
3727 tree delta0 = delta_from_ptrmemfunc (op0);
3728 tree e1 = cp_build_binary_op (location,
3731 fold_convert (TREE_TYPE (pfn0),
3734 tree e2 = cp_build_binary_op (location,
3739 e2 = cp_build_binary_op (location,
3740 EQ_EXPR, e2, integer_zero_node,
3742 op0 = cp_build_binary_op (location,
3743 TRUTH_ANDIF_EXPR, e1, e2,
3745 op1 = cp_convert (TREE_TYPE (op0), integer_one_node);
3749 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3750 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3752 result_type = TREE_TYPE (op0);
3754 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3755 return cp_build_binary_op (location, code, op1, op0, complain);
3756 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1))
3759 /* E will be the final comparison. */
3761 /* E1 and E2 are for scratch. */
3769 type = composite_pointer_type (type0, type1, op0, op1, "comparison",
3772 if (!same_type_p (TREE_TYPE (op0), type))
3773 op0 = cp_convert_and_check (type, op0);
3774 if (!same_type_p (TREE_TYPE (op1), type))
3775 op1 = cp_convert_and_check (type, op1);
3777 if (op0 == error_mark_node || op1 == error_mark_node)
3778 return error_mark_node;
3780 if (TREE_SIDE_EFFECTS (op0))
3781 op0 = save_expr (op0);
3782 if (TREE_SIDE_EFFECTS (op1))
3783 op1 = save_expr (op1);
3785 pfn0 = pfn_from_ptrmemfunc (op0);
3786 pfn1 = pfn_from_ptrmemfunc (op1);
3787 delta0 = delta_from_ptrmemfunc (op0);
3788 delta1 = delta_from_ptrmemfunc (op1);
3789 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3790 == ptrmemfunc_vbit_in_delta)
3795 && ((op0.delta == op1.delta)
3796 || (!op0.pfn && op0.delta & 1 == 0
3797 && op1.delta & 1 == 0))
3799 The reason for the `!op0.pfn' bit is that a NULL
3800 pointer-to-member is any member with a zero PFN and
3801 LSB of the DELTA field is 0. */
3803 e1 = cp_build_binary_op (location, BIT_AND_EXPR,
3807 e1 = cp_build_binary_op (location,
3808 EQ_EXPR, e1, integer_zero_node,
3810 e2 = cp_build_binary_op (location, BIT_AND_EXPR,
3814 e2 = cp_build_binary_op (location,
3815 EQ_EXPR, e2, integer_zero_node,
3817 e1 = cp_build_binary_op (location,
3818 TRUTH_ANDIF_EXPR, e2, e1,
3820 e2 = cp_build_binary_op (location, EQ_EXPR,
3822 fold_convert (TREE_TYPE (pfn0),
3825 e2 = cp_build_binary_op (location,
3826 TRUTH_ANDIF_EXPR, e2, e1, complain);
3827 e1 = cp_build_binary_op (location,
3828 EQ_EXPR, delta0, delta1, complain);
3829 e1 = cp_build_binary_op (location,
3830 TRUTH_ORIF_EXPR, e1, e2, complain);
3837 && (!op0.pfn || op0.delta == op1.delta))
3839 The reason for the `!op0.pfn' bit is that a NULL
3840 pointer-to-member is any member with a zero PFN; the
3841 DELTA field is unspecified. */
3843 e1 = cp_build_binary_op (location,
3844 EQ_EXPR, delta0, delta1, complain);
3845 e2 = cp_build_binary_op (location,
3848 fold_convert (TREE_TYPE (pfn0),
3851 e1 = cp_build_binary_op (location,
3852 TRUTH_ORIF_EXPR, e1, e2, complain);
3854 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3855 e = cp_build_binary_op (location,
3856 TRUTH_ANDIF_EXPR, e2, e1, complain);
3857 if (code == EQ_EXPR)
3859 return cp_build_binary_op (location,
3860 EQ_EXPR, e, integer_zero_node, complain);
3864 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3865 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3867 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3868 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3876 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3877 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3879 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3880 result_type = composite_pointer_type (type0, type1, op0, op1,
3881 "comparison", complain);
3888 if (TREE_CODE (orig_op0) == STRING_CST
3889 || TREE_CODE (orig_op1) == STRING_CST)
3891 if (complain & tf_warning)
3892 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3895 build_type = boolean_type_node;
3896 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3897 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3899 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3900 result_type = composite_pointer_type (type0, type1, op0, op1,
3901 "comparison", complain);
3902 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3903 && integer_zerop (op1))
3904 result_type = type0;
3905 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3906 && integer_zerop (op0))
3907 result_type = type1;
3908 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3910 result_type = type0;
3911 if (complain & tf_error)
3912 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3914 return error_mark_node;
3916 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3918 result_type = type1;
3919 if (complain & tf_error)
3920 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3922 return error_mark_node;
3926 case UNORDERED_EXPR:
3933 build_type = integer_type_node;
3934 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3936 if (complain & tf_error)
3937 error ("unordered comparison on non-floating point argument");
3938 return error_mark_node;
3947 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
3948 || code0 == ENUMERAL_TYPE)
3949 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3950 || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE)))
3951 arithmetic_types_p = 1;
3954 arithmetic_types_p = 0;
3955 /* Vector arithmetic is only allowed when both sides are vectors. */
3956 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3958 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3959 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3962 binary_op_error (location, code, type0, type1);
3963 return error_mark_node;
3965 arithmetic_types_p = 1;
3968 /* Determine the RESULT_TYPE, if it is not already known. */
3970 && arithmetic_types_p
3971 && (shorten || common || short_compare))
3972 result_type = cp_common_type (type0, type1);
3976 if (complain & tf_error)
3977 error ("invalid operands of types %qT and %qT to binary %qO",
3978 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3979 return error_mark_node;
3982 /* If we're in a template, the only thing we need to know is the
3984 if (processing_template_decl)
3986 /* Since the middle-end checks the type when doing a build2, we
3987 need to build the tree in pieces. This built tree will never
3988 get out of the front-end as we replace it when instantiating
3990 tree tmp = build2 (resultcode,
3991 build_type ? build_type : result_type,
3993 TREE_OPERAND (tmp, 0) = op0;
3997 if (arithmetic_types_p)
3999 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
4001 /* For certain operations (which identify themselves by shorten != 0)
4002 if both args were extended from the same smaller type,
4003 do the arithmetic in that type and then extend.
4005 shorten !=0 and !=1 indicates a bitwise operation.
4006 For them, this optimization is safe only if
4007 both args are zero-extended or both are sign-extended.
4008 Otherwise, we might change the result.
4009 E.g., (short)-1 | (unsigned short)-1 is (int)-1
4010 but calculated in (unsigned short) it would be (unsigned short)-1. */
4012 if (shorten && none_complex)
4014 final_type = result_type;
4015 result_type = shorten_binary_op (result_type, op0, op1,
4019 /* Comparison operations are shortened too but differently.
4020 They identify themselves by setting short_compare = 1. */
4024 /* Don't write &op0, etc., because that would prevent op0
4025 from being kept in a register.
4026 Instead, make copies of the our local variables and
4027 pass the copies by reference, then copy them back afterward. */
4028 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
4029 enum tree_code xresultcode = resultcode;
4031 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
4033 return cp_convert (boolean_type_node, val);
4034 op0 = xop0, op1 = xop1;
4036 resultcode = xresultcode;
4039 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
4040 && warn_sign_compare
4041 && !TREE_NO_WARNING (orig_op0)
4042 && !TREE_NO_WARNING (orig_op1)
4043 /* Do not warn until the template is instantiated; we cannot
4044 bound the ranges of the arguments until that point. */
4045 && !processing_template_decl
4046 && (complain & tf_warning)
4047 && c_inhibit_evaluation_warnings == 0)
4049 warn_for_sign_compare (location, orig_op0, orig_op1, op0, op1,
4050 result_type, resultcode);
4054 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
4055 Then the expression will be built.
4056 It will be given type FINAL_TYPE if that is nonzero;
4057 otherwise, it will be given type RESULT_TYPE. */
4060 if (TREE_TYPE (op0) != result_type)
4061 op0 = cp_convert_and_check (result_type, op0);
4062 if (TREE_TYPE (op1) != result_type)
4063 op1 = cp_convert_and_check (result_type, op1);
4065 if (op0 == error_mark_node || op1 == error_mark_node)
4066 return error_mark_node;
4069 if (build_type == NULL_TREE)
4070 build_type = result_type;
4072 result = build2 (resultcode, build_type, op0, op1);
4073 result = fold_if_not_in_template (result);
4074 if (final_type != 0)
4075 result = cp_convert (final_type, result);
4077 if (TREE_OVERFLOW_P (result)
4078 && !TREE_OVERFLOW_P (op0)
4079 && !TREE_OVERFLOW_P (op1))
4080 overflow_warning (location, result);
4085 /* Return a tree for the sum or difference (RESULTCODE says which)
4086 of pointer PTROP and integer INTOP. */
4089 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
4091 tree res_type = TREE_TYPE (ptrop);
4093 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
4094 in certain circumstance (when it's valid to do so). So we need
4095 to make sure it's complete. We don't need to check here, if we
4096 can actually complete it at all, as those checks will be done in
4097 pointer_int_sum() anyway. */
4098 complete_type (TREE_TYPE (res_type));
4100 return pointer_int_sum (input_location, resultcode, ptrop,
4101 fold_if_not_in_template (intop));
4104 /* Return a tree for the difference of pointers OP0 and OP1.
4105 The resulting tree has type int. */
4108 pointer_diff (tree op0, tree op1, tree ptrtype)
4111 tree restype = ptrdiff_type_node;
4112 tree target_type = TREE_TYPE (ptrtype);
4114 if (!complete_type_or_else (target_type, NULL_TREE))
4115 return error_mark_node;
4117 if (TREE_CODE (target_type) == VOID_TYPE)
4118 permerror (input_location, "ISO C++ forbids using pointer of type %<void *%> in subtraction");
4119 if (TREE_CODE (target_type) == FUNCTION_TYPE)
4120 permerror (input_location, "ISO C++ forbids using pointer to a function in subtraction");
4121 if (TREE_CODE (target_type) == METHOD_TYPE)
4122 permerror (input_location, "ISO C++ forbids using pointer to a method in subtraction");
4124 /* First do the subtraction as integers;
4125 then drop through to build the divide operator. */
4127 op0 = cp_build_binary_op (input_location,
4129 cp_convert (restype, op0),
4130 cp_convert (restype, op1),
4131 tf_warning_or_error);
4133 /* This generates an error if op1 is a pointer to an incomplete type. */
4134 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
4135 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
4137 op1 = (TYPE_PTROB_P (ptrtype)
4138 ? size_in_bytes (target_type)
4139 : integer_one_node);
4141 /* Do the division. */
4143 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
4144 return fold_if_not_in_template (result);
4147 /* Construct and perhaps optimize a tree representation
4148 for a unary operation. CODE, a tree_code, specifies the operation
4149 and XARG is the operand. */
4152 build_x_unary_op (enum tree_code code, tree xarg, tsubst_flags_t complain)
4154 tree orig_expr = xarg;
4158 if (processing_template_decl)
4160 if (type_dependent_expression_p (xarg))
4161 return build_min_nt (code, xarg, NULL_TREE);
4163 xarg = build_non_dependent_expr (xarg);
4168 /* [expr.unary.op] says:
4170 The address of an object of incomplete type can be taken.
4172 (And is just the ordinary address operator, not an overloaded
4173 "operator &".) However, if the type is a template
4174 specialization, we must complete the type at this point so that
4175 an overloaded "operator &" will be available if required. */
4176 if (code == ADDR_EXPR
4177 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
4178 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
4179 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
4180 || (TREE_CODE (xarg) == OFFSET_REF)))
4181 /* Don't look for a function. */;
4183 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
4184 /*overloaded_p=*/NULL, complain);
4185 if (!exp && code == ADDR_EXPR)
4187 if (is_overloaded_fn (xarg))
4189 tree fn = get_first_fn (xarg);
4190 if (DECL_CONSTRUCTOR_P (fn) || DECL_DESTRUCTOR_P (fn))
4193 (DECL_CONSTRUCTOR_P (fn) ? "constructor" : "destructor");
4194 error ("taking address of %s %qE", type, xarg);
4195 return error_mark_node;
4199 /* A pointer to member-function can be formed only by saying
4201 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
4202 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
4204 if (TREE_CODE (xarg) != OFFSET_REF
4205 || !TYPE_P (TREE_OPERAND (xarg, 0)))
4207 error ("invalid use of %qE to form a pointer-to-member-function",
4209 if (TREE_CODE (xarg) != OFFSET_REF)
4210 inform (input_location, " a qualified-id is required");
4211 return error_mark_node;
4215 error ("parentheses around %qE cannot be used to form a"
4216 " pointer-to-member-function",
4218 PTRMEM_OK_P (xarg) = 1;
4222 if (TREE_CODE (xarg) == OFFSET_REF)
4224 ptrmem = PTRMEM_OK_P (xarg);
4226 if (!ptrmem && !flag_ms_extensions
4227 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
4229 /* A single non-static member, make sure we don't allow a
4230 pointer-to-member. */
4231 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
4232 TREE_OPERAND (xarg, 0),
4233 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
4234 PTRMEM_OK_P (xarg) = ptrmem;
4237 else if (TREE_CODE (xarg) == TARGET_EXPR && (complain & tf_warning))
4238 warning (0, "taking address of temporary");
4239 exp = cp_build_unary_op (ADDR_EXPR, xarg, 0, complain);
4242 if (processing_template_decl && exp != error_mark_node)
4243 exp = build_min_non_dep (code, exp, orig_expr,
4244 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
4245 if (TREE_CODE (exp) == ADDR_EXPR)
4246 PTRMEM_OK_P (exp) = ptrmem;
4250 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
4251 constants, where a null value is represented by an INTEGER_CST of
4255 cp_truthvalue_conversion (tree expr)
4257 tree type = TREE_TYPE (expr);
4258 if (TYPE_PTRMEM_P (type))
4259 return build_binary_op (EXPR_LOCATION (expr),
4260 NE_EXPR, expr, integer_zero_node, 1);
4262 return c_common_truthvalue_conversion (input_location, expr);
4265 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
4268 condition_conversion (tree expr)
4271 if (processing_template_decl)
4273 t = perform_implicit_conversion (boolean_type_node, expr,
4274 tf_warning_or_error);
4275 t = fold_build_cleanup_point_expr (boolean_type_node, t);
4279 /* Returns the address of T. This function will fold away
4280 ADDR_EXPR of INDIRECT_REF. */
4283 build_address (tree t)
4285 if (error_operand_p (t) || !cxx_mark_addressable (t))
4286 return error_mark_node;
4287 t = build_fold_addr_expr (t);
4288 if (TREE_CODE (t) != ADDR_EXPR)
4293 /* Returns the address of T with type TYPE. */
4296 build_typed_address (tree t, tree type)
4298 if (error_operand_p (t) || !cxx_mark_addressable (t))
4299 return error_mark_node;
4300 t = build_fold_addr_expr_with_type (t, type);
4301 if (TREE_CODE (t) != ADDR_EXPR)
4306 /* Return a NOP_EXPR converting EXPR to TYPE. */
4309 build_nop (tree type, tree expr)
4311 if (type == error_mark_node || error_operand_p (expr))
4313 return build1 (NOP_EXPR, type, expr);
4316 /* C++: Must handle pointers to members.
4318 Perhaps type instantiation should be extended to handle conversion
4319 from aggregates to types we don't yet know we want? (Or are those
4320 cases typically errors which should be reported?)
4322 NOCONVERT nonzero suppresses the default promotions
4323 (such as from short to int). */
4326 cp_build_unary_op (enum tree_code code, tree xarg, int noconvert,
4327 tsubst_flags_t complain)
4329 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
4332 const char *errstring = NULL;
4334 const char *invalid_op_diag;
4336 if (error_operand_p (arg))
4337 return error_mark_node;
4339 if ((invalid_op_diag
4340 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
4345 error (invalid_op_diag);
4346 return error_mark_node;
4351 case UNARY_PLUS_EXPR:
4354 int flags = WANT_ARITH | WANT_ENUM;
4355 /* Unary plus (but not unary minus) is allowed on pointers. */
4356 if (code == UNARY_PLUS_EXPR)
4357 flags |= WANT_POINTER;
4358 arg = build_expr_type_conversion (flags, arg, true);
4360 errstring = (code == NEGATE_EXPR
4361 ? "wrong type argument to unary minus"
4362 : "wrong type argument to unary plus");
4365 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4366 arg = perform_integral_promotions (arg);
4368 /* Make sure the result is not an lvalue: a unary plus or minus
4369 expression is always a rvalue. */
4376 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4380 arg = default_conversion (arg);
4382 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM
4385 errstring = "wrong type argument to bit-complement";
4386 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4387 arg = perform_integral_promotions (arg);
4391 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4392 errstring = "wrong type argument to abs";
4393 else if (!noconvert)
4394 arg = default_conversion (arg);
4398 /* Conjugating a real value is a no-op, but allow it anyway. */
4399 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4400 errstring = "wrong type argument to conjugation";
4401 else if (!noconvert)
4402 arg = default_conversion (arg);
4405 case TRUTH_NOT_EXPR:
4406 arg = perform_implicit_conversion (boolean_type_node, arg,
4408 val = invert_truthvalue_loc (input_location, arg);
4409 if (arg != error_mark_node)
4411 errstring = "in argument to unary !";
4418 if (TREE_CODE (arg) == COMPLEX_CST)
4419 return TREE_REALPART (arg);
4420 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4422 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4423 return fold_if_not_in_template (arg);
4429 if (TREE_CODE (arg) == COMPLEX_CST)
4430 return TREE_IMAGPART (arg);
4431 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4433 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4434 return fold_if_not_in_template (arg);
4437 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4439 case PREINCREMENT_EXPR:
4440 case POSTINCREMENT_EXPR:
4441 case PREDECREMENT_EXPR:
4442 case POSTDECREMENT_EXPR:
4443 /* Handle complex lvalues (when permitted)
4444 by reduction to simpler cases. */
4446 val = unary_complex_lvalue (code, arg);
4450 /* Increment or decrement the real part of the value,
4451 and don't change the imaginary part. */
4452 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4456 arg = stabilize_reference (arg);
4457 real = cp_build_unary_op (REALPART_EXPR, arg, 1, complain);
4458 imag = cp_build_unary_op (IMAGPART_EXPR, arg, 1, complain);
4459 real = cp_build_unary_op (code, real, 1, complain);
4460 if (real == error_mark_node || imag == error_mark_node)
4461 return error_mark_node;
4462 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4466 /* Report invalid types. */
4468 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4471 if (code == PREINCREMENT_EXPR)
4472 errstring ="no pre-increment operator for type";
4473 else if (code == POSTINCREMENT_EXPR)
4474 errstring ="no post-increment operator for type";
4475 else if (code == PREDECREMENT_EXPR)
4476 errstring ="no pre-decrement operator for type";
4478 errstring ="no post-decrement operator for type";
4481 else if (arg == error_mark_node)
4482 return error_mark_node;
4484 /* Report something read-only. */
4486 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4487 || TREE_READONLY (arg))
4489 if (complain & tf_error)
4490 readonly_error (arg, ((code == PREINCREMENT_EXPR
4491 || code == POSTINCREMENT_EXPR)
4492 ? "increment" : "decrement"));
4494 return error_mark_node;
4499 tree declared_type = unlowered_expr_type (arg);
4501 argtype = TREE_TYPE (arg);
4503 /* ARM $5.2.5 last annotation says this should be forbidden. */
4504 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4506 if (complain & tf_error)
4507 permerror (input_location, (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4508 ? G_("ISO C++ forbids incrementing an enum")
4509 : G_("ISO C++ forbids decrementing an enum"));
4511 return error_mark_node;
4514 /* Compute the increment. */
4516 if (TREE_CODE (argtype) == POINTER_TYPE)
4518 tree type = complete_type (TREE_TYPE (argtype));
4520 if (!COMPLETE_OR_VOID_TYPE_P (type))
4522 if (complain & tf_error)
4523 error (((code == PREINCREMENT_EXPR
4524 || code == POSTINCREMENT_EXPR))
4525 ? G_("cannot increment a pointer to incomplete type %qT")
4526 : G_("cannot decrement a pointer to incomplete type %qT"),
4527 TREE_TYPE (argtype));
4529 return error_mark_node;
4531 else if ((pedantic || warn_pointer_arith)
4532 && !TYPE_PTROB_P (argtype))
4534 if (complain & tf_error)
4535 permerror (input_location, (code == PREINCREMENT_EXPR
4536 || code == POSTINCREMENT_EXPR)
4537 ? G_("ISO C++ forbids incrementing a pointer of type %qT")
4538 : G_("ISO C++ forbids decrementing a pointer of type %qT"),
4541 return error_mark_node;
4544 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4547 inc = integer_one_node;
4549 inc = cp_convert (argtype, inc);
4551 /* Complain about anything else that is not a true lvalue. */
4552 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4553 || code == POSTINCREMENT_EXPR)
4554 ? lv_increment : lv_decrement),
4556 return error_mark_node;
4558 /* Forbid using -- on `bool'. */
4559 if (same_type_p (declared_type, boolean_type_node))
4561 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4563 if (complain & tf_error)
4564 error ("invalid use of Boolean expression as operand "
4565 "to %<operator--%>");
4566 return error_mark_node;
4568 val = boolean_increment (code, arg);
4571 val = build2 (code, TREE_TYPE (arg), arg, inc);
4573 TREE_SIDE_EFFECTS (val) = 1;
4578 /* Note that this operation never does default_conversion
4579 regardless of NOCONVERT. */
4581 argtype = lvalue_type (arg);
4583 if (TREE_CODE (arg) == OFFSET_REF)
4586 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4588 tree type = build_pointer_type (TREE_TYPE (argtype));
4589 arg = build1 (CONVERT_EXPR, type, arg);
4592 else if (pedantic && DECL_MAIN_P (arg))
4595 /* Apparently a lot of autoconf scripts for C++ packages do this,
4596 so only complain if -pedantic. */
4597 if (complain & (flag_pedantic_errors ? tf_error : tf_warning))
4598 pedwarn (input_location, OPT_pedantic,
4599 "ISO C++ forbids taking address of function %<::main%>");
4600 else if (flag_pedantic_errors)
4601 return error_mark_node;
4604 /* Let &* cancel out to simplify resulting code. */
4605 if (TREE_CODE (arg) == INDIRECT_REF)
4607 /* We don't need to have `current_class_ptr' wrapped in a
4608 NON_LVALUE_EXPR node. */
4609 if (arg == current_class_ref)
4610 return current_class_ptr;
4612 arg = TREE_OPERAND (arg, 0);
4613 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4615 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4616 arg = build1 (CONVERT_EXPR, type, arg);
4619 /* Don't let this be an lvalue. */
4624 /* Uninstantiated types are all functions. Taking the
4625 address of a function is a no-op, so just return the
4628 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4629 || !IDENTIFIER_OPNAME_P (arg));
4631 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4632 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4634 /* They're trying to take the address of a unique non-static
4635 member function. This is ill-formed (except in MS-land),
4636 but let's try to DTRT.
4637 Note: We only handle unique functions here because we don't
4638 want to complain if there's a static overload; non-unique
4639 cases will be handled by instantiate_type. But we need to
4640 handle this case here to allow casts on the resulting PMF.
4641 We could defer this in non-MS mode, but it's easier to give
4642 a useful error here. */
4644 /* Inside constant member functions, the `this' pointer
4645 contains an extra const qualifier. TYPE_MAIN_VARIANT
4646 is used here to remove this const from the diagnostics
4647 and the created OFFSET_REF. */
4648 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4649 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4652 if (! flag_ms_extensions)
4654 tree name = DECL_NAME (fn);
4655 if (!(complain & tf_error))
4656 return error_mark_node;
4657 else if (current_class_type
4658 && TREE_OPERAND (arg, 0) == current_class_ref)
4659 /* An expression like &memfn. */
4660 permerror (input_location, "ISO C++ forbids taking the address of an unqualified"
4661 " or parenthesized non-static member function to form"
4662 " a pointer to member function. Say %<&%T::%D%>",
4665 permerror (input_location, "ISO C++ forbids taking the address of a bound member"
4666 " function to form a pointer to member function."
4670 arg = build_offset_ref (base, fn, /*address_p=*/true);
4674 if (type_unknown_p (arg))
4675 return build1 (ADDR_EXPR, unknown_type_node, arg);
4677 /* Handle complex lvalues (when permitted)
4678 by reduction to simpler cases. */
4679 val = unary_complex_lvalue (code, arg);
4683 switch (TREE_CODE (arg))
4687 case FIX_TRUNC_EXPR:
4688 /* Even if we're not being pedantic, we cannot allow this
4689 extension when we're instantiating in a SFINAE
4691 if (! lvalue_p (arg) && complain == tf_none)
4693 if (complain & tf_error)
4694 permerror (input_location, "ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4696 return error_mark_node;
4701 arg = BASELINK_FUNCTIONS (arg);
4705 arg = OVL_CURRENT (arg);
4709 /* Turn a reference to a non-static data member into a
4710 pointer-to-member. */
4715 if (!PTRMEM_OK_P (arg))
4716 return cp_build_unary_op (code, arg, 0, complain);
4718 t = TREE_OPERAND (arg, 1);
4719 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4721 if (complain & tf_error)
4722 error ("cannot create pointer to reference member %qD", t);
4723 return error_mark_node;
4726 type = build_ptrmem_type (context_for_name_lookup (t),
4728 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4736 /* Anything not already handled and not a true memory reference
4738 if (TREE_CODE (argtype) != FUNCTION_TYPE
4739 && TREE_CODE (argtype) != METHOD_TYPE
4740 && TREE_CODE (arg) != OFFSET_REF
4741 && !lvalue_or_else (arg, lv_addressof, complain))
4742 return error_mark_node;
4744 if (argtype != error_mark_node)
4745 argtype = build_pointer_type (argtype);
4747 /* In a template, we are processing a non-dependent expression
4748 so we can just form an ADDR_EXPR with the correct type. */
4749 if (processing_template_decl || TREE_CODE (arg) != COMPONENT_REF)
4751 val = build_address (arg);
4752 if (TREE_CODE (arg) == OFFSET_REF)
4753 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4755 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4757 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4759 /* We can only get here with a single static member
4761 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4762 && DECL_STATIC_FUNCTION_P (fn));
4764 val = build_address (fn);
4765 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4766 /* Do not lose object's side effects. */
4767 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4768 TREE_OPERAND (arg, 0), val);
4770 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4772 if (complain & tf_error)
4773 error ("attempt to take address of bit-field structure member %qD",
4774 TREE_OPERAND (arg, 1));
4775 return error_mark_node;
4779 tree object = TREE_OPERAND (arg, 0);
4780 tree field = TREE_OPERAND (arg, 1);
4781 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4782 (TREE_TYPE (object), decl_type_context (field)));
4783 val = build_address (arg);
4786 if (TREE_CODE (argtype) == POINTER_TYPE
4787 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4789 build_ptrmemfunc_type (argtype);
4790 val = build_ptrmemfunc (argtype, val, 0,
4791 /*c_cast_p=*/false);
4803 argtype = TREE_TYPE (arg);
4804 return fold_if_not_in_template (build1 (code, argtype, arg));
4807 if (complain & tf_error)
4808 error ("%s", errstring);
4809 return error_mark_node;
4812 /* Hook for the c-common bits that build a unary op. */
4814 build_unary_op (location_t location ATTRIBUTE_UNUSED,
4815 enum tree_code code, tree xarg, int noconvert)
4817 return cp_build_unary_op (code, xarg, noconvert, tf_warning_or_error);
4820 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4821 for certain kinds of expressions which are not really lvalues
4822 but which we can accept as lvalues.
4824 If ARG is not a kind of expression we can handle, return
4828 unary_complex_lvalue (enum tree_code code, tree arg)
4830 /* Inside a template, making these kinds of adjustments is
4831 pointless; we are only concerned with the type of the
4833 if (processing_template_decl)
4836 /* Handle (a, b) used as an "lvalue". */
4837 if (TREE_CODE (arg) == COMPOUND_EXPR)
4839 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 1), 0,
4840 tf_warning_or_error);
4841 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4842 TREE_OPERAND (arg, 0), real_result);
4845 /* Handle (a ? b : c) used as an "lvalue". */
4846 if (TREE_CODE (arg) == COND_EXPR
4847 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4848 return rationalize_conditional_expr (code, arg, tf_warning_or_error);
4850 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4851 if (TREE_CODE (arg) == MODIFY_EXPR
4852 || TREE_CODE (arg) == PREINCREMENT_EXPR
4853 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4855 tree lvalue = TREE_OPERAND (arg, 0);
4856 if (TREE_SIDE_EFFECTS (lvalue))
4858 lvalue = stabilize_reference (lvalue);
4859 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4860 lvalue, TREE_OPERAND (arg, 1));
4862 return unary_complex_lvalue
4863 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4866 if (code != ADDR_EXPR)
4869 /* Handle (a = b) used as an "lvalue" for `&'. */
4870 if (TREE_CODE (arg) == MODIFY_EXPR
4871 || TREE_CODE (arg) == INIT_EXPR)
4873 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 0), 0,
4874 tf_warning_or_error);
4875 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4877 TREE_NO_WARNING (arg) = 1;
4881 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4882 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4883 || TREE_CODE (arg) == OFFSET_REF)
4886 /* We permit compiler to make function calls returning
4887 objects of aggregate type look like lvalues. */
4891 if (TREE_CODE (targ) == SAVE_EXPR)
4892 targ = TREE_OPERAND (targ, 0);
4894 if (TREE_CODE (targ) == CALL_EXPR && MAYBE_CLASS_TYPE_P (TREE_TYPE (targ)))
4896 if (TREE_CODE (arg) == SAVE_EXPR)
4899 targ = build_cplus_new (TREE_TYPE (arg), arg);
4900 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4903 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4904 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4905 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4908 /* Don't let anything else be handled specially. */
4912 /* Mark EXP saying that we need to be able to take the
4913 address of it; it should not be allocated in a register.
4914 Value is true if successful.
4916 C++: we do not allow `current_class_ptr' to be addressable. */
4919 cxx_mark_addressable (tree exp)
4924 switch (TREE_CODE (x))
4931 x = TREE_OPERAND (x, 0);
4935 if (x == current_class_ptr)
4937 error ("cannot take the address of %<this%>, which is an rvalue expression");
4938 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4944 /* Caller should not be trying to mark initialized
4945 constant fields addressable. */
4946 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4947 || DECL_IN_AGGR_P (x) == 0
4949 || DECL_EXTERNAL (x));
4954 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4955 && !DECL_ARTIFICIAL (x))
4957 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4960 ("address of explicit register variable %qD requested", x);
4963 else if (extra_warnings)
4965 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
4967 TREE_ADDRESSABLE (x) = 1;
4971 TREE_ADDRESSABLE (x) = 1;
4975 TREE_ADDRESSABLE (x) = 1;
4979 TREE_ADDRESSABLE (x) = 1;
4980 cxx_mark_addressable (TREE_OPERAND (x, 0));
4988 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4991 build_x_conditional_expr (tree ifexp, tree op1, tree op2,
4992 tsubst_flags_t complain)
4994 tree orig_ifexp = ifexp;
4995 tree orig_op1 = op1;
4996 tree orig_op2 = op2;
4999 if (processing_template_decl)
5001 /* The standard says that the expression is type-dependent if
5002 IFEXP is type-dependent, even though the eventual type of the
5003 expression doesn't dependent on IFEXP. */
5004 if (type_dependent_expression_p (ifexp)
5005 /* As a GNU extension, the middle operand may be omitted. */
5006 || (op1 && type_dependent_expression_p (op1))
5007 || type_dependent_expression_p (op2))
5008 return build_min_nt (COND_EXPR, ifexp, op1, op2);
5009 ifexp = build_non_dependent_expr (ifexp);
5011 op1 = build_non_dependent_expr (op1);
5012 op2 = build_non_dependent_expr (op2);
5015 expr = build_conditional_expr (ifexp, op1, op2, complain);
5016 if (processing_template_decl && expr != error_mark_node)
5017 return build_min_non_dep (COND_EXPR, expr,
5018 orig_ifexp, orig_op1, orig_op2);
5022 /* Given a list of expressions, return a compound expression
5023 that performs them all and returns the value of the last of them. */
5025 tree build_x_compound_expr_from_list (tree list, const char *msg)
5027 tree expr = TREE_VALUE (list);
5029 if (TREE_CHAIN (list))
5032 permerror (input_location, "%s expression list treated as compound expression", msg);
5034 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
5035 expr = build_x_compound_expr (expr, TREE_VALUE (list),
5036 tf_warning_or_error);
5042 /* Like build_x_compound_expr_from_list, but using a VEC. */
5045 build_x_compound_expr_from_vec (VEC(tree,gc) *vec, const char *msg)
5047 if (VEC_empty (tree, vec))
5049 else if (VEC_length (tree, vec) == 1)
5050 return VEC_index (tree, vec, 0);
5058 permerror (input_location,
5059 "%s expression list treated as compound expression",
5062 expr = VEC_index (tree, vec, 0);
5063 for (ix = 1; VEC_iterate (tree, vec, ix, t); ++ix)
5064 expr = build_x_compound_expr (expr, t, tf_warning_or_error);
5070 /* Handle overloading of the ',' operator when needed. */
5073 build_x_compound_expr (tree op1, tree op2, tsubst_flags_t complain)
5076 tree orig_op1 = op1;
5077 tree orig_op2 = op2;
5079 if (processing_template_decl)
5081 if (type_dependent_expression_p (op1)
5082 || type_dependent_expression_p (op2))
5083 return build_min_nt (COMPOUND_EXPR, op1, op2);
5084 op1 = build_non_dependent_expr (op1);
5085 op2 = build_non_dependent_expr (op2);
5088 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
5089 /*overloaded_p=*/NULL, complain);
5091 result = cp_build_compound_expr (op1, op2, complain);
5093 if (processing_template_decl && result != error_mark_node)
5094 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
5099 /* Like cp_build_compound_expr, but for the c-common bits. */
5102 build_compound_expr (location_t loc ATTRIBUTE_UNUSED, tree lhs, tree rhs)
5104 return cp_build_compound_expr (lhs, rhs, tf_warning_or_error);
5107 /* Build a compound expression. */
5110 cp_build_compound_expr (tree lhs, tree rhs, tsubst_flags_t complain)
5112 lhs = convert_to_void (lhs, "left-hand operand of comma", complain);
5114 if (lhs == error_mark_node || rhs == error_mark_node)
5115 return error_mark_node;
5117 if (TREE_CODE (rhs) == TARGET_EXPR)
5119 /* If the rhs is a TARGET_EXPR, then build the compound
5120 expression inside the target_expr's initializer. This
5121 helps the compiler to eliminate unnecessary temporaries. */
5122 tree init = TREE_OPERAND (rhs, 1);
5124 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
5125 TREE_OPERAND (rhs, 1) = init;
5130 if (type_unknown_p (rhs))
5132 error ("no context to resolve type of %qE", rhs);
5133 return error_mark_node;
5136 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
5139 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
5140 casts away constness. CAST gives the type of cast.
5142 ??? This function warns for casting away any qualifier not just
5143 const. We would like to specify exactly what qualifiers are casted
5148 check_for_casting_away_constness (tree src_type, tree dest_type,
5149 enum tree_code cast)
5151 /* C-style casts are allowed to cast away constness. With
5152 WARN_CAST_QUAL, we still want to issue a warning. */
5153 if (cast == CAST_EXPR && !warn_cast_qual)
5156 if (!casts_away_constness (src_type, dest_type))
5162 warning (OPT_Wcast_qual,
5163 "cast from type %qT to type %qT casts away qualifiers",
5164 src_type, dest_type);
5167 case STATIC_CAST_EXPR:
5168 error ("static_cast from type %qT to type %qT casts away qualifiers",
5169 src_type, dest_type);
5172 case REINTERPRET_CAST_EXPR:
5173 error ("reinterpret_cast from type %qT to type %qT casts away qualifiers",
5174 src_type, dest_type);
5181 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
5182 (another pointer-to-member type in the same hierarchy) and return
5183 the converted expression. If ALLOW_INVERSE_P is permitted, a
5184 pointer-to-derived may be converted to pointer-to-base; otherwise,
5185 only the other direction is permitted. If C_CAST_P is true, this
5186 conversion is taking place as part of a C-style cast. */
5189 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
5192 if (TYPE_PTRMEM_P (type))
5196 if (TREE_CODE (expr) == PTRMEM_CST)
5197 expr = cplus_expand_constant (expr);
5198 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
5199 TYPE_PTRMEM_CLASS_TYPE (type),
5202 if (!integer_zerop (delta))
5204 tree cond, op1, op2;
5206 cond = cp_build_binary_op (input_location,
5209 build_int_cst (TREE_TYPE (expr), -1),
5210 tf_warning_or_error);
5211 op1 = build_nop (ptrdiff_type_node, expr);
5212 op2 = cp_build_binary_op (input_location,
5213 PLUS_EXPR, op1, delta,
5214 tf_warning_or_error);
5216 expr = fold_build3_loc (input_location,
5217 COND_EXPR, ptrdiff_type_node, cond, op1, op2);
5221 return build_nop (type, expr);
5224 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
5225 allow_inverse_p, c_cast_p);
5228 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
5229 a version of EXPR that has TREE_OVERFLOW set if it is set in ORIG.
5230 Otherwise, return EXPR unchanged. */
5233 ignore_overflows (tree expr, tree orig)
5235 if (TREE_CODE (expr) == INTEGER_CST
5236 && CONSTANT_CLASS_P (orig)
5237 && TREE_CODE (orig) != STRING_CST
5238 && TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig))
5240 if (!TREE_OVERFLOW (orig))
5241 /* Ensure constant sharing. */
5242 expr = build_int_cst_wide (TREE_TYPE (expr),
5243 TREE_INT_CST_LOW (expr),
5244 TREE_INT_CST_HIGH (expr));
5247 /* Avoid clobbering a shared constant. */
5248 expr = copy_node (expr);
5249 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
5255 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
5256 this static_cast is being attempted as one of the possible casts
5257 allowed by a C-style cast. (In that case, accessibility of base
5258 classes is not considered, and it is OK to cast away
5259 constness.) Return the result of the cast. *VALID_P is set to
5260 indicate whether or not the cast was valid. */
5263 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
5264 bool *valid_p, tsubst_flags_t complain)
5270 /* Assume the cast is valid. */
5273 intype = TREE_TYPE (expr);
5275 /* Save casted types in the function's used types hash table. */
5276 used_types_insert (type);
5278 /* [expr.static.cast]
5280 An lvalue of type "cv1 B", where B is a class type, can be cast
5281 to type "reference to cv2 D", where D is a class derived (clause
5282 _class.derived_) from B, if a valid standard conversion from
5283 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
5284 same cv-qualification as, or greater cv-qualification than, cv1,
5285 and B is not a virtual base class of D. */
5286 /* We check this case before checking the validity of "TYPE t =
5287 EXPR;" below because for this case:
5290 struct D : public B { D(const B&); };
5292 void f() { static_cast<const D&>(b); }
5294 we want to avoid constructing a new D. The standard is not
5295 completely clear about this issue, but our interpretation is
5296 consistent with other compilers. */
5297 if (TREE_CODE (type) == REFERENCE_TYPE
5298 && CLASS_TYPE_P (TREE_TYPE (type))
5299 && CLASS_TYPE_P (intype)
5300 && (TYPE_REF_IS_RVALUE (type) || real_lvalue_p (expr))
5301 && DERIVED_FROM_P (intype, TREE_TYPE (type))
5302 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
5303 build_pointer_type (TYPE_MAIN_VARIANT
5304 (TREE_TYPE (type))))
5306 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5310 /* There is a standard conversion from "D*" to "B*" even if "B"
5311 is ambiguous or inaccessible. If this is really a
5312 static_cast, then we check both for inaccessibility and
5313 ambiguity. However, if this is a static_cast being performed
5314 because the user wrote a C-style cast, then accessibility is
5316 base = lookup_base (TREE_TYPE (type), intype,
5317 c_cast_p ? ba_unique : ba_check,
5320 /* Convert from "B*" to "D*". This function will check that "B"
5321 is not a virtual base of "D". */
5322 expr = build_base_path (MINUS_EXPR, build_address (expr),
5323 base, /*nonnull=*/false);
5324 /* Convert the pointer to a reference -- but then remember that
5325 there are no expressions with reference type in C++. */
5326 return convert_from_reference (cp_fold_convert (type, expr));
5329 /* "An lvalue of type cv1 T1 can be cast to type rvalue reference to
5330 cv2 T2 if cv2 T2 is reference-compatible with cv1 T1 (8.5.3)." */
5331 if (TREE_CODE (type) == REFERENCE_TYPE
5332 && TYPE_REF_IS_RVALUE (type)
5333 && real_lvalue_p (expr)
5334 && reference_related_p (TREE_TYPE (type), intype)
5335 && (c_cast_p || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5337 expr = build_typed_address (expr, type);
5338 return convert_from_reference (expr);
5343 /* [expr.static.cast]
5345 An expression e can be explicitly converted to a type T using a
5346 static_cast of the form static_cast<T>(e) if the declaration T
5347 t(e);" is well-formed, for some invented temporary variable
5349 result = perform_direct_initialization_if_possible (type, expr,
5350 c_cast_p, complain);
5353 result = convert_from_reference (result);
5355 /* Ignore any integer overflow caused by the cast. */
5356 result = ignore_overflows (result, orig);
5358 /* [expr.static.cast]
5360 If T is a reference type, the result is an lvalue; otherwise,
5361 the result is an rvalue. */
5362 if (TREE_CODE (type) != REFERENCE_TYPE)
5363 result = rvalue (result);
5367 /* [expr.static.cast]
5369 Any expression can be explicitly converted to type cv void. */
5370 if (TREE_CODE (type) == VOID_TYPE)
5371 return convert_to_void (expr, /*implicit=*/NULL, complain);
5373 /* [expr.static.cast]
5375 The inverse of any standard conversion sequence (clause _conv_),
5376 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
5377 (_conv.array_), function-to-pointer (_conv.func_), and boolean
5378 (_conv.bool_) conversions, can be performed explicitly using
5379 static_cast subject to the restriction that the explicit
5380 conversion does not cast away constness (_expr.const.cast_), and
5381 the following additional rules for specific cases: */
5382 /* For reference, the conversions not excluded are: integral
5383 promotions, floating point promotion, integral conversions,
5384 floating point conversions, floating-integral conversions,
5385 pointer conversions, and pointer to member conversions. */
5388 A value of integral _or enumeration_ type can be explicitly
5389 converted to an enumeration type. */
5390 /* The effect of all that is that any conversion between any two
5391 types which are integral, floating, or enumeration types can be
5393 if ((INTEGRAL_OR_ENUMERATION_TYPE_P (type)
5394 || SCALAR_FLOAT_TYPE_P (type))
5395 && (INTEGRAL_OR_ENUMERATION_TYPE_P (intype)
5396 || SCALAR_FLOAT_TYPE_P (intype)))
5398 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
5400 /* Ignore any integer overflow caused by the cast. */
5401 expr = ignore_overflows (expr, orig);
5405 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
5406 && CLASS_TYPE_P (TREE_TYPE (type))
5407 && CLASS_TYPE_P (TREE_TYPE (intype))
5408 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
5409 (TREE_TYPE (intype))),
5410 build_pointer_type (TYPE_MAIN_VARIANT
5411 (TREE_TYPE (type)))))
5416 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5417 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
5418 c_cast_p ? ba_unique : ba_check,
5420 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
5423 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5424 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5431 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
5432 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
5434 if (TYPE_PTRMEM_P (type))
5436 t1 = (build_ptrmem_type
5438 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
5439 t2 = (build_ptrmem_type
5441 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
5448 if (can_convert (t1, t2) || can_convert (t2, t1))
5451 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5452 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
5457 /* [expr.static.cast]
5459 An rvalue of type "pointer to cv void" can be explicitly
5460 converted to a pointer to object type. A value of type pointer
5461 to object converted to "pointer to cv void" and back to the
5462 original pointer type will have its original value. */
5463 if (TREE_CODE (intype) == POINTER_TYPE
5464 && VOID_TYPE_P (TREE_TYPE (intype))
5465 && TYPE_PTROB_P (type))
5468 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5469 return build_nop (type, expr);
5473 return error_mark_node;
5476 /* Return an expression representing static_cast<TYPE>(EXPR). */
5479 build_static_cast (tree type, tree expr, tsubst_flags_t complain)
5484 if (type == error_mark_node || expr == error_mark_node)
5485 return error_mark_node;
5487 if (processing_template_decl)
5489 expr = build_min (STATIC_CAST_EXPR, type, expr);
5490 /* We don't know if it will or will not have side effects. */
5491 TREE_SIDE_EFFECTS (expr) = 1;
5492 return convert_from_reference (expr);
5495 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5496 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5497 if (TREE_CODE (type) != REFERENCE_TYPE
5498 && TREE_CODE (expr) == NOP_EXPR
5499 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5500 expr = TREE_OPERAND (expr, 0);
5502 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p,
5507 if (complain & tf_error)
5508 error ("invalid static_cast from type %qT to type %qT",
5509 TREE_TYPE (expr), type);
5510 return error_mark_node;
5513 /* EXPR is an expression with member function or pointer-to-member
5514 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5515 not permitted by ISO C++, but we accept it in some modes. If we
5516 are not in one of those modes, issue a diagnostic. Return the
5517 converted expression. */
5520 convert_member_func_to_ptr (tree type, tree expr)
5525 intype = TREE_TYPE (expr);
5526 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
5527 || TREE_CODE (intype) == METHOD_TYPE);
5529 if (pedantic || warn_pmf2ptr)
5530 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpmf_conversions,
5531 "converting from %qT to %qT", intype, type);
5533 if (TREE_CODE (intype) == METHOD_TYPE)
5534 expr = build_addr_func (expr);
5535 else if (TREE_CODE (expr) == PTRMEM_CST)
5536 expr = build_address (PTRMEM_CST_MEMBER (expr));
5539 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
5540 decl = build_address (decl);
5541 expr = get_member_function_from_ptrfunc (&decl, expr);
5544 return build_nop (type, expr);
5547 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5548 If C_CAST_P is true, this reinterpret cast is being done as part of
5549 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5550 indicate whether or not reinterpret_cast was valid. */
5553 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5554 bool *valid_p, tsubst_flags_t complain)
5558 /* Assume the cast is invalid. */
5562 if (type == error_mark_node || error_operand_p (expr))
5563 return error_mark_node;
5565 intype = TREE_TYPE (expr);
5567 /* Save casted types in the function's used types hash table. */
5568 used_types_insert (type);
5570 /* [expr.reinterpret.cast]
5571 An lvalue expression of type T1 can be cast to the type
5572 "reference to T2" if an expression of type "pointer to T1" can be
5573 explicitly converted to the type "pointer to T2" using a
5574 reinterpret_cast. */
5575 if (TREE_CODE (type) == REFERENCE_TYPE)
5577 if (! real_lvalue_p (expr))
5579 if (complain & tf_error)
5580 error ("invalid cast of an rvalue expression of type "
5583 return error_mark_node;
5586 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5587 "B" are related class types; the reinterpret_cast does not
5588 adjust the pointer. */
5589 if (TYPE_PTR_P (intype)
5590 && (complain & tf_warning)
5591 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5592 COMPARE_BASE | COMPARE_DERIVED)))
5593 warning (0, "casting %qT to %qT does not dereference pointer",
5596 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
5597 if (expr != error_mark_node)
5598 expr = build_reinterpret_cast_1
5599 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5601 if (expr != error_mark_node)
5602 expr = cp_build_indirect_ref (expr, 0, complain);
5606 /* As a G++ extension, we consider conversions from member
5607 functions, and pointers to member functions to
5608 pointer-to-function and pointer-to-void types. If
5609 -Wno-pmf-conversions has not been specified,
5610 convert_member_func_to_ptr will issue an error message. */
5611 if ((TYPE_PTRMEMFUNC_P (intype)
5612 || TREE_CODE (intype) == METHOD_TYPE)
5613 && TYPE_PTR_P (type)
5614 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5615 || VOID_TYPE_P (TREE_TYPE (type))))
5616 return convert_member_func_to_ptr (type, expr);
5618 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5619 array-to-pointer, and function-to-pointer conversions are
5621 expr = decay_conversion (expr);
5623 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5624 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5625 if (TREE_CODE (expr) == NOP_EXPR
5626 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5627 expr = TREE_OPERAND (expr, 0);
5629 if (error_operand_p (expr))
5630 return error_mark_node;
5632 intype = TREE_TYPE (expr);
5634 /* [expr.reinterpret.cast]
5635 A pointer can be converted to any integral type large enough to
5637 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5639 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5641 if (complain & tf_error)
5642 permerror (input_location, "cast from %qT to %qT loses precision",
5645 return error_mark_node;
5648 /* [expr.reinterpret.cast]
5649 A value of integral or enumeration type can be explicitly
5650 converted to a pointer. */
5651 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5654 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5655 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5656 return fold_if_not_in_template (build_nop (type, expr));
5657 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5658 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5663 check_for_casting_away_constness (intype, type, REINTERPRET_CAST_EXPR);
5664 /* Warn about possible alignment problems. */
5665 if (STRICT_ALIGNMENT && warn_cast_align
5666 && (complain & tf_warning)
5667 && !VOID_TYPE_P (type)
5668 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5669 && COMPLETE_TYPE_P (TREE_TYPE (type))
5670 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5671 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5672 warning (OPT_Wcast_align, "cast from %qT to %qT "
5673 "increases required alignment of target type", intype, type);
5675 /* We need to strip nops here, because the front end likes to
5676 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5678 if (warn_strict_aliasing <= 2)
5679 strict_aliasing_warning (intype, type, sexpr);
5681 return fold_if_not_in_template (build_nop (type, expr));
5683 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5684 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5686 if (pedantic && (complain & tf_warning))
5687 /* Only issue a warning, as we have always supported this
5688 where possible, and it is necessary in some cases. DR 195
5689 addresses this issue, but as of 2004/10/26 is still in
5691 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5692 return fold_if_not_in_template (build_nop (type, expr));
5694 else if (TREE_CODE (type) == VECTOR_TYPE)
5695 return fold_if_not_in_template (convert_to_vector (type, expr));
5696 else if (TREE_CODE (intype) == VECTOR_TYPE
5697 && INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5698 return fold_if_not_in_template (convert_to_integer (type, expr));
5703 if (complain & tf_error)
5704 error ("invalid cast from type %qT to type %qT", intype, type);
5705 return error_mark_node;
5708 return cp_convert (type, expr);
5712 build_reinterpret_cast (tree type, tree expr, tsubst_flags_t complain)
5714 if (type == error_mark_node || expr == error_mark_node)
5715 return error_mark_node;
5717 if (processing_template_decl)
5719 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5721 if (!TREE_SIDE_EFFECTS (t)
5722 && type_dependent_expression_p (expr))
5723 /* There might turn out to be side effects inside expr. */
5724 TREE_SIDE_EFFECTS (t) = 1;
5725 return convert_from_reference (t);
5728 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5729 /*valid_p=*/NULL, complain);
5732 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5733 return an appropriate expression. Otherwise, return
5734 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5735 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5736 performing a C-style cast, its value upon return will indicate
5737 whether or not the conversion succeeded. */
5740 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5744 tree reference_type;
5746 /* Callers are responsible for handling error_mark_node as a
5747 destination type. */
5748 gcc_assert (dst_type != error_mark_node);
5749 /* In a template, callers should be building syntactic
5750 representations of casts, not using this machinery. */
5751 gcc_assert (!processing_template_decl);
5753 /* Assume the conversion is invalid. */
5757 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5760 error ("invalid use of const_cast with type %qT, "
5761 "which is not a pointer, "
5762 "reference, nor a pointer-to-data-member type", dst_type);
5763 return error_mark_node;
5766 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5769 error ("invalid use of const_cast with type %qT, which is a pointer "
5770 "or reference to a function type", dst_type);
5771 return error_mark_node;
5774 /* Save casted types in the function's used types hash table. */
5775 used_types_insert (dst_type);
5777 src_type = TREE_TYPE (expr);
5778 /* Expressions do not really have reference types. */
5779 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5780 src_type = TREE_TYPE (src_type);
5782 /* [expr.const.cast]
5784 An lvalue of type T1 can be explicitly converted to an lvalue of
5785 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5786 types) if a pointer to T1 can be explicitly converted to the type
5787 pointer to T2 using a const_cast. */
5788 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5790 reference_type = dst_type;
5791 if (! real_lvalue_p (expr))
5794 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5795 src_type, dst_type);
5796 return error_mark_node;
5798 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5799 src_type = build_pointer_type (src_type);
5803 reference_type = NULL_TREE;
5804 /* If the destination type is not a reference type, the
5805 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5806 conversions are performed. */
5807 src_type = type_decays_to (src_type);
5808 if (src_type == error_mark_node)
5809 return error_mark_node;
5812 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5813 && comp_ptr_ttypes_const (dst_type, src_type))
5818 /* This cast is actually a C-style cast. Issue a warning if
5819 the user is making a potentially unsafe cast. */
5820 check_for_casting_away_constness (src_type, dst_type, CAST_EXPR);
5824 expr = cp_build_unary_op (ADDR_EXPR, expr, 0,
5825 complain? tf_warning_or_error : tf_none);
5826 expr = build_nop (reference_type, expr);
5827 return convert_from_reference (expr);
5831 expr = decay_conversion (expr);
5832 /* build_c_cast puts on a NOP_EXPR to make the result not an
5833 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5834 non-lvalue context. */
5835 if (TREE_CODE (expr) == NOP_EXPR
5836 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5837 expr = TREE_OPERAND (expr, 0);
5838 return build_nop (dst_type, expr);
5843 error ("invalid const_cast from type %qT to type %qT",
5844 src_type, dst_type);
5845 return error_mark_node;
5849 build_const_cast (tree type, tree expr, tsubst_flags_t complain)
5851 if (type == error_mark_node || error_operand_p (expr))
5852 return error_mark_node;
5854 if (processing_template_decl)
5856 tree t = build_min (CONST_CAST_EXPR, type, expr);
5858 if (!TREE_SIDE_EFFECTS (t)
5859 && type_dependent_expression_p (expr))
5860 /* There might turn out to be side effects inside expr. */
5861 TREE_SIDE_EFFECTS (t) = 1;
5862 return convert_from_reference (t);
5865 return build_const_cast_1 (type, expr, complain & tf_error,
5869 /* Like cp_build_c_cast, but for the c-common bits. */
5872 build_c_cast (location_t loc ATTRIBUTE_UNUSED, tree type, tree expr)
5874 return cp_build_c_cast (type, expr, tf_warning_or_error);
5877 /* Build an expression representing an explicit C-style cast to type
5878 TYPE of expression EXPR. */
5881 cp_build_c_cast (tree type, tree expr, tsubst_flags_t complain)
5887 if (type == error_mark_node || error_operand_p (expr))
5888 return error_mark_node;
5890 if (processing_template_decl)
5892 tree t = build_min (CAST_EXPR, type,
5893 tree_cons (NULL_TREE, value, NULL_TREE));
5894 /* We don't know if it will or will not have side effects. */
5895 TREE_SIDE_EFFECTS (t) = 1;
5896 return convert_from_reference (t);
5899 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5900 'Class') should always be retained, because this information aids
5901 in method lookup. */
5902 if (objc_is_object_ptr (type)
5903 && objc_is_object_ptr (TREE_TYPE (expr)))
5904 return build_nop (type, expr);
5906 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5907 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5908 if (TREE_CODE (type) != REFERENCE_TYPE
5909 && TREE_CODE (value) == NOP_EXPR
5910 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5911 value = TREE_OPERAND (value, 0);
5913 if (TREE_CODE (type) == ARRAY_TYPE)
5915 /* Allow casting from T1* to T2[] because Cfront allows it.
5916 NIHCL uses it. It is not valid ISO C++ however. */
5917 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5919 if (complain & tf_error)
5920 permerror (input_location, "ISO C++ forbids casting to an array type %qT", type);
5922 return error_mark_node;
5923 type = build_pointer_type (TREE_TYPE (type));
5927 if (complain & tf_error)
5928 error ("ISO C++ forbids casting to an array type %qT", type);
5929 return error_mark_node;
5933 if (TREE_CODE (type) == FUNCTION_TYPE
5934 || TREE_CODE (type) == METHOD_TYPE)
5936 if (complain & tf_error)
5937 error ("invalid cast to function type %qT", type);
5938 return error_mark_node;
5941 /* A C-style cast can be a const_cast. */
5942 result = build_const_cast_1 (type, value, /*complain=*/false,
5947 /* Or a static cast. */
5948 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5949 &valid_p, complain);
5950 /* Or a reinterpret_cast. */
5952 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5953 &valid_p, complain);
5954 /* The static_cast or reinterpret_cast may be followed by a
5957 /* A valid cast may result in errors if, for example, a
5958 conversion to am ambiguous base class is required. */
5959 && !error_operand_p (result))
5963 /* Non-class rvalues always have cv-unqualified type. */
5964 if (!CLASS_TYPE_P (type))
5965 type = TYPE_MAIN_VARIANT (type);
5966 result_type = TREE_TYPE (result);
5967 if (!CLASS_TYPE_P (result_type))
5968 result_type = TYPE_MAIN_VARIANT (result_type);
5969 /* If the type of RESULT does not match TYPE, perform a
5970 const_cast to make it match. If the static_cast or
5971 reinterpret_cast succeeded, we will differ by at most
5972 cv-qualification, so the follow-on const_cast is guaranteed
5974 if (!same_type_p (non_reference (type), non_reference (result_type)))
5976 result = build_const_cast_1 (type, result, false, &valid_p);
5977 gcc_assert (valid_p);
5982 return error_mark_node;
5985 /* For use from the C common bits. */
5987 build_modify_expr (location_t location ATTRIBUTE_UNUSED,
5988 tree lhs, tree lhs_origtype ATTRIBUTE_UNUSED,
5989 enum tree_code modifycode,
5990 location_t rhs_location ATTRIBUTE_UNUSED, tree rhs,
5991 tree rhs_origtype ATTRIBUTE_UNUSED)
5993 return cp_build_modify_expr (lhs, modifycode, rhs, tf_warning_or_error);
5996 /* Build an assignment expression of lvalue LHS from value RHS.
5997 MODIFYCODE is the code for a binary operator that we use
5998 to combine the old value of LHS with RHS to get the new value.
5999 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
6001 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
6004 cp_build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6005 tsubst_flags_t complain)
6009 tree lhstype = TREE_TYPE (lhs);
6010 tree olhstype = lhstype;
6011 bool plain_assign = (modifycode == NOP_EXPR);
6013 /* Avoid duplicate error messages from operands that had errors. */
6014 if (error_operand_p (lhs) || error_operand_p (rhs))
6015 return error_mark_node;
6017 /* Handle control structure constructs used as "lvalues". */
6018 switch (TREE_CODE (lhs))
6020 /* Handle --foo = 5; as these are valid constructs in C++. */
6021 case PREDECREMENT_EXPR:
6022 case PREINCREMENT_EXPR:
6023 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
6024 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
6025 stabilize_reference (TREE_OPERAND (lhs, 0)),
6026 TREE_OPERAND (lhs, 1));
6027 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0),
6028 modifycode, rhs, complain);
6029 if (newrhs == error_mark_node)
6030 return error_mark_node;
6031 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
6033 /* Handle (a, b) used as an "lvalue". */
6035 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6036 modifycode, rhs, complain);
6037 if (newrhs == error_mark_node)
6038 return error_mark_node;
6039 return build2 (COMPOUND_EXPR, lhstype,
6040 TREE_OPERAND (lhs, 0), newrhs);
6043 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
6044 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
6045 stabilize_reference (TREE_OPERAND (lhs, 0)),
6046 TREE_OPERAND (lhs, 1));
6047 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs,
6049 if (newrhs == error_mark_node)
6050 return error_mark_node;
6051 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
6055 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
6056 when neither operand has side-effects. */
6057 if (!lvalue_or_else (lhs, lv_assign, complain))
6058 return error_mark_node;
6060 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
6061 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
6063 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
6064 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
6066 TREE_OPERAND (lhs, 0),
6067 TREE_OPERAND (lhs, 1)),
6068 TREE_OPERAND (lhs, 0),
6069 TREE_OPERAND (lhs, 1));
6072 /* Handle (a ? b : c) used as an "lvalue". */
6075 /* Produce (a ? (b = rhs) : (c = rhs))
6076 except that the RHS goes through a save-expr
6077 so the code to compute it is only emitted once. */
6079 tree preeval = NULL_TREE;
6081 if (VOID_TYPE_P (TREE_TYPE (rhs)))
6083 if (complain & tf_error)
6084 error ("void value not ignored as it ought to be");
6085 return error_mark_node;
6088 rhs = stabilize_expr (rhs, &preeval);
6090 /* Check this here to avoid odd errors when trying to convert
6091 a throw to the type of the COND_EXPR. */
6092 if (!lvalue_or_else (lhs, lv_assign, complain))
6093 return error_mark_node;
6095 cond = build_conditional_expr
6096 (TREE_OPERAND (lhs, 0),
6097 cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6098 modifycode, rhs, complain),
6099 cp_build_modify_expr (TREE_OPERAND (lhs, 2),
6100 modifycode, rhs, complain),
6103 if (cond == error_mark_node)
6105 /* Make sure the code to compute the rhs comes out
6106 before the split. */
6108 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
6116 if (modifycode == INIT_EXPR)
6118 if (BRACE_ENCLOSED_INITIALIZER_P (rhs))
6119 /* Do the default thing. */;
6120 else if (TREE_CODE (rhs) == CONSTRUCTOR)
6122 /* Compound literal. */
6123 if (! same_type_p (TREE_TYPE (rhs), lhstype))
6124 /* Call convert to generate an error; see PR 11063. */
6125 rhs = convert (lhstype, rhs);
6126 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
6127 TREE_SIDE_EFFECTS (result) = 1;
6130 else if (! MAYBE_CLASS_TYPE_P (lhstype))
6131 /* Do the default thing. */;
6134 VEC(tree,gc) *rhs_vec = make_tree_vector_single (rhs);
6135 result = build_special_member_call (lhs, complete_ctor_identifier,
6136 &rhs_vec, lhstype, LOOKUP_NORMAL,
6138 release_tree_vector (rhs_vec);
6139 if (result == NULL_TREE)
6140 return error_mark_node;
6146 lhs = require_complete_type (lhs);
6147 if (lhs == error_mark_node)
6148 return error_mark_node;
6150 if (modifycode == NOP_EXPR)
6152 /* `operator=' is not an inheritable operator. */
6153 if (! MAYBE_CLASS_TYPE_P (lhstype))
6154 /* Do the default thing. */;
6157 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
6158 lhs, rhs, make_node (NOP_EXPR),
6159 /*overloaded_p=*/NULL,
6161 if (result == NULL_TREE)
6162 return error_mark_node;
6169 /* A binary op has been requested. Combine the old LHS
6170 value with the RHS producing the value we should actually
6171 store into the LHS. */
6172 gcc_assert (!((TREE_CODE (lhstype) == REFERENCE_TYPE
6173 && MAYBE_CLASS_TYPE_P (TREE_TYPE (lhstype)))
6174 || MAYBE_CLASS_TYPE_P (lhstype)));
6176 lhs = stabilize_reference (lhs);
6177 newrhs = cp_build_binary_op (input_location,
6178 modifycode, lhs, rhs,
6180 if (newrhs == error_mark_node)
6182 if (complain & tf_error)
6183 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
6184 TREE_TYPE (lhs), TREE_TYPE (rhs));
6185 return error_mark_node;
6188 /* Now it looks like a plain assignment. */
6189 modifycode = NOP_EXPR;
6191 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
6192 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
6195 /* The left-hand side must be an lvalue. */
6196 if (!lvalue_or_else (lhs, lv_assign, complain))
6197 return error_mark_node;
6199 /* Warn about modifying something that is `const'. Don't warn if
6200 this is initialization. */
6201 if (modifycode != INIT_EXPR
6202 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
6203 /* Functions are not modifiable, even though they are
6205 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
6206 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
6207 /* If it's an aggregate and any field is const, then it is
6208 effectively const. */
6209 || (CLASS_TYPE_P (lhstype)
6210 && C_TYPE_FIELDS_READONLY (lhstype))))
6212 if (complain & tf_error)
6213 readonly_error (lhs, "assignment");
6215 return error_mark_node;
6218 /* If storing into a structure or union member, it may have been given a
6219 lowered bitfield type. We need to convert to the declared type first,
6220 so retrieve it now. */
6222 olhstype = unlowered_expr_type (lhs);
6224 /* Convert new value to destination type. */
6226 if (TREE_CODE (lhstype) == ARRAY_TYPE)
6230 if (BRACE_ENCLOSED_INITIALIZER_P (rhs))
6231 rhs = digest_init (lhstype, rhs);
6233 else if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
6234 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
6236 if (complain & tf_error)
6237 error ("incompatible types in assignment of %qT to %qT",
6238 TREE_TYPE (rhs), lhstype);
6239 return error_mark_node;
6242 /* Allow array assignment in compiler-generated code. */
6243 else if (!current_function_decl
6244 || !DECL_ARTIFICIAL (current_function_decl))
6246 /* This routine is used for both initialization and assignment.
6247 Make sure the diagnostic message differentiates the context. */
6248 if (complain & tf_error)
6250 if (modifycode == INIT_EXPR)
6251 error ("array used as initializer");
6253 error ("invalid array assignment");
6255 return error_mark_node;
6258 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
6259 ? 1 + (modifycode != INIT_EXPR): 0;
6260 return build_vec_init (lhs, NULL_TREE, newrhs,
6261 /*explicit_value_init_p=*/false,
6262 from_array, complain);
6265 if (modifycode == INIT_EXPR)
6266 /* Calls with INIT_EXPR are all direct-initialization, so don't set
6267 LOOKUP_ONLYCONVERTING. */
6268 newrhs = convert_for_initialization (lhs, olhstype, newrhs, LOOKUP_NORMAL,
6269 "initialization", NULL_TREE, 0,
6272 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
6273 NULL_TREE, 0, complain, LOOKUP_IMPLICIT);
6275 if (!same_type_p (lhstype, olhstype))
6276 newrhs = cp_convert_and_check (lhstype, newrhs);
6278 if (modifycode != INIT_EXPR)
6280 if (TREE_CODE (newrhs) == CALL_EXPR
6281 && TYPE_NEEDS_CONSTRUCTING (lhstype))
6282 newrhs = build_cplus_new (lhstype, newrhs);
6284 /* Can't initialize directly from a TARGET_EXPR, since that would
6285 cause the lhs to be constructed twice, and possibly result in
6286 accidental self-initialization. So we force the TARGET_EXPR to be
6287 expanded without a target. */
6288 if (TREE_CODE (newrhs) == TARGET_EXPR)
6289 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
6290 TREE_OPERAND (newrhs, 0));
6293 if (newrhs == error_mark_node)
6294 return error_mark_node;
6296 if (c_dialect_objc () && flag_objc_gc)
6298 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
6304 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
6305 lhstype, lhs, newrhs);
6307 TREE_SIDE_EFFECTS (result) = 1;
6309 TREE_NO_WARNING (result) = 1;
6315 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6316 tsubst_flags_t complain)
6318 if (processing_template_decl)
6319 return build_min_nt (MODOP_EXPR, lhs,
6320 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
6322 if (modifycode != NOP_EXPR)
6324 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
6325 make_node (modifycode),
6326 /*overloaded_p=*/NULL,
6330 TREE_NO_WARNING (rval) = 1;
6334 return cp_build_modify_expr (lhs, modifycode, rhs, complain);
6337 /* Helper function for get_delta_difference which assumes FROM is a base
6338 class of TO. Returns a delta for the conversion of pointer-to-member
6339 of FROM to pointer-to-member of TO. If the conversion is invalid,
6340 returns zero. If FROM is not a base class of TO, returns NULL_TREE.
6341 If C_CAST_P is true, this conversion is taking place as part of a C-style
6345 get_delta_difference_1 (tree from, tree to, bool c_cast_p)
6350 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
6351 if (kind == bk_inaccessible || kind == bk_ambig)
6353 error (" in pointer to member function conversion");
6354 return size_zero_node;
6358 if (kind != bk_via_virtual)
6359 return BINFO_OFFSET (binfo);
6361 /* FROM is a virtual base class of TO. Issue an error or warning
6362 depending on whether or not this is a reinterpret cast. */
6364 error ("pointer to member conversion via virtual base %qT",
6365 BINFO_TYPE (binfo_from_vbase (binfo)));
6367 return size_zero_node;
6374 /* Get difference in deltas for different pointer to member function
6375 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
6376 the conversion is invalid, the constant is zero. If
6377 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
6378 If C_CAST_P is true this conversion is taking place as part of a
6381 Note that the naming of FROM and TO is kind of backwards; the return
6382 value is what we add to a TO in order to get a FROM. They are named
6383 this way because we call this function to find out how to convert from
6384 a pointer to member of FROM to a pointer to member of TO. */
6387 get_delta_difference (tree from, tree to,
6388 bool allow_inverse_p,
6393 if (same_type_ignoring_top_level_qualifiers_p (from, to))
6394 /* Pointer to member of incomplete class is permitted*/
6395 result = size_zero_node;
6397 result = get_delta_difference_1 (from, to, c_cast_p);
6401 if (!allow_inverse_p)
6403 error_not_base_type (from, to);
6404 error (" in pointer to member conversion");
6405 result = size_zero_node;
6409 result = get_delta_difference_1 (to, from, c_cast_p);
6412 result = size_diffop_loc (input_location,
6413 size_zero_node, result);
6416 error_not_base_type (from, to);
6417 error (" in pointer to member conversion");
6418 result = size_zero_node;
6423 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
6427 /* Return a constructor for the pointer-to-member-function TYPE using
6428 the other components as specified. */
6431 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
6436 VEC(constructor_elt, gc) *v;
6438 /* Pull the FIELD_DECLs out of the type. */
6439 pfn_field = TYPE_FIELDS (type);
6440 delta_field = TREE_CHAIN (pfn_field);
6442 /* Make sure DELTA has the type we want. */
6443 delta = convert_and_check (delta_type_node, delta);
6445 /* Convert to the correct target type if necessary. */
6446 pfn = fold_convert (TREE_TYPE (pfn_field), pfn);
6448 /* Finish creating the initializer. */
6449 v = VEC_alloc(constructor_elt, gc, 2);
6450 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
6451 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
6452 u = build_constructor (type, v);
6453 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
6454 TREE_STATIC (u) = (TREE_CONSTANT (u)
6455 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
6457 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
6462 /* Build a constructor for a pointer to member function. It can be
6463 used to initialize global variables, local variable, or used
6464 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
6467 If FORCE is nonzero, then force this conversion, even if
6468 we would rather not do it. Usually set when using an explicit
6469 cast. A C-style cast is being processed iff C_CAST_P is true.
6471 Return error_mark_node, if something goes wrong. */
6474 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
6480 if (error_operand_p (pfn))
6481 return error_mark_node;
6483 pfn_type = TREE_TYPE (pfn);
6484 to_type = build_ptrmemfunc_type (type);
6486 /* Handle multiple conversions of pointer to member functions. */
6487 if (TYPE_PTRMEMFUNC_P (pfn_type))
6489 tree delta = NULL_TREE;
6490 tree npfn = NULL_TREE;
6494 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
6495 error ("invalid conversion to type %qT from type %qT",
6498 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
6499 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
6503 /* We don't have to do any conversion to convert a
6504 pointer-to-member to its own type. But, we don't want to
6505 just return a PTRMEM_CST if there's an explicit cast; that
6506 cast should make the expression an invalid template argument. */
6507 if (TREE_CODE (pfn) != PTRMEM_CST)
6509 if (same_type_p (to_type, pfn_type))
6511 else if (integer_zerop (n))
6512 return build_reinterpret_cast (to_type, pfn,
6513 tf_warning_or_error);
6516 if (TREE_SIDE_EFFECTS (pfn))
6517 pfn = save_expr (pfn);
6519 /* Obtain the function pointer and the current DELTA. */
6520 if (TREE_CODE (pfn) == PTRMEM_CST)
6521 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
6524 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
6525 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
6528 /* Just adjust the DELTA field. */
6529 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6530 (TREE_TYPE (delta), ptrdiff_type_node));
6531 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
6532 n = cp_build_binary_op (input_location,
6533 LSHIFT_EXPR, n, integer_one_node,
6534 tf_warning_or_error);
6535 delta = cp_build_binary_op (input_location,
6536 PLUS_EXPR, delta, n, tf_warning_or_error);
6537 return build_ptrmemfunc1 (to_type, delta, npfn);
6540 /* Handle null pointer to member function conversions. */
6541 if (integer_zerop (pfn))
6543 pfn = build_c_cast (input_location, type, integer_zero_node);
6544 return build_ptrmemfunc1 (to_type,
6549 if (type_unknown_p (pfn))
6550 return instantiate_type (type, pfn, tf_warning_or_error);
6552 fn = TREE_OPERAND (pfn, 0);
6553 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
6554 /* In a template, we will have preserved the
6556 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
6557 return make_ptrmem_cst (to_type, fn);
6560 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
6563 ??? There is no consistency as to the types returned for the above
6564 values. Some code acts as if it were a sizetype and some as if it were
6565 integer_type_node. */
6568 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
6570 tree type = TREE_TYPE (cst);
6571 tree fn = PTRMEM_CST_MEMBER (cst);
6572 tree ptr_class, fn_class;
6574 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6576 /* The class that the function belongs to. */
6577 fn_class = DECL_CONTEXT (fn);
6579 /* The class that we're creating a pointer to member of. */
6580 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
6582 /* First, calculate the adjustment to the function's class. */
6583 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
6586 if (!DECL_VIRTUAL_P (fn))
6587 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
6590 /* If we're dealing with a virtual function, we have to adjust 'this'
6591 again, to point to the base which provides the vtable entry for
6592 fn; the call will do the opposite adjustment. */
6593 tree orig_class = DECL_CONTEXT (fn);
6594 tree binfo = binfo_or_else (orig_class, fn_class);
6595 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6596 *delta, BINFO_OFFSET (binfo));
6597 *delta = fold_if_not_in_template (*delta);
6599 /* We set PFN to the vtable offset at which the function can be
6600 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6601 case delta is shifted left, and then incremented). */
6602 *pfn = DECL_VINDEX (fn);
6603 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
6604 TYPE_SIZE_UNIT (vtable_entry_type));
6605 *pfn = fold_if_not_in_template (*pfn);
6607 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
6609 case ptrmemfunc_vbit_in_pfn:
6610 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6612 *pfn = fold_if_not_in_template (*pfn);
6615 case ptrmemfunc_vbit_in_delta:
6616 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6617 *delta, integer_one_node);
6618 *delta = fold_if_not_in_template (*delta);
6619 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6620 *delta, integer_one_node);
6621 *delta = fold_if_not_in_template (*delta);
6628 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6629 *pfn = fold_if_not_in_template (*pfn);
6633 /* Return an expression for PFN from the pointer-to-member function
6637 pfn_from_ptrmemfunc (tree t)
6639 if (TREE_CODE (t) == PTRMEM_CST)
6644 expand_ptrmemfunc_cst (t, &delta, &pfn);
6649 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6652 /* Return an expression for DELTA from the pointer-to-member function
6656 delta_from_ptrmemfunc (tree t)
6658 if (TREE_CODE (t) == PTRMEM_CST)
6663 expand_ptrmemfunc_cst (t, &delta, &pfn);
6668 return build_ptrmemfunc_access_expr (t, delta_identifier);
6671 /* Convert value RHS to type TYPE as preparation for an assignment to
6672 an lvalue of type TYPE. ERRTYPE is a string to use in error
6673 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6674 are doing the conversion in order to pass the PARMNUMth argument of
6678 convert_for_assignment (tree type, tree rhs,
6679 const char *errtype, tree fndecl, int parmnum,
6680 tsubst_flags_t complain, int flags)
6683 enum tree_code coder;
6685 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6686 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6687 rhs = TREE_OPERAND (rhs, 0);
6689 rhstype = TREE_TYPE (rhs);
6690 coder = TREE_CODE (rhstype);
6692 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6693 && vector_types_convertible_p (type, rhstype, true))
6694 return convert (type, rhs);
6696 if (rhs == error_mark_node || rhstype == error_mark_node)
6697 return error_mark_node;
6698 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6699 return error_mark_node;
6701 /* The RHS of an assignment cannot have void type. */
6702 if (coder == VOID_TYPE)
6704 if (complain & tf_error)
6705 error ("void value not ignored as it ought to be");
6706 return error_mark_node;
6709 /* Simplify the RHS if possible. */
6710 if (TREE_CODE (rhs) == CONST_DECL)
6711 rhs = DECL_INITIAL (rhs);
6713 if (c_dialect_objc ())
6716 tree rname = fndecl;
6718 if (!strcmp (errtype, "assignment"))
6720 else if (!strcmp (errtype, "initialization"))
6724 tree selector = objc_message_selector ();
6728 if (selector && parmno > 1)
6735 if (objc_compare_types (type, rhstype, parmno, rname))
6736 return convert (type, rhs);
6741 The expression is implicitly converted (clause _conv_) to the
6742 cv-unqualified type of the left operand.
6744 We allow bad conversions here because by the time we get to this point
6745 we are committed to doing the conversion. If we end up doing a bad
6746 conversion, convert_like will complain. */
6747 if (!can_convert_arg_bad (type, rhstype, rhs, flags))
6749 /* When -Wno-pmf-conversions is use, we just silently allow
6750 conversions from pointers-to-members to plain pointers. If
6751 the conversion doesn't work, cp_convert will complain. */
6753 && TYPE_PTR_P (type)
6754 && TYPE_PTRMEMFUNC_P (rhstype))
6755 rhs = cp_convert (strip_top_quals (type), rhs);
6758 if (complain & tf_error)
6760 /* If the right-hand side has unknown type, then it is an
6761 overloaded function. Call instantiate_type to get error
6763 if (rhstype == unknown_type_node)
6764 instantiate_type (type, rhs, tf_warning_or_error);
6766 error ("cannot convert %qT to %qT for argument %qP to %qD",
6767 rhstype, type, parmnum, fndecl);
6769 error ("cannot convert %qT to %qT in %s", rhstype, type,
6772 return error_mark_node;
6775 if (warn_missing_format_attribute)
6777 const enum tree_code codel = TREE_CODE (type);
6778 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6780 && check_missing_format_attribute (type, rhstype)
6781 && (complain & tf_warning))
6782 warning (OPT_Wmissing_format_attribute,
6783 "%s might be a candidate for a format attribute",
6787 /* If -Wparentheses, warn about a = b = c when a has type bool and b
6789 if (warn_parentheses
6790 && type == boolean_type_node
6791 && TREE_CODE (rhs) == MODIFY_EXPR
6792 && !TREE_NO_WARNING (rhs)
6793 && TREE_CODE (TREE_TYPE (rhs)) != BOOLEAN_TYPE
6794 && (complain & tf_warning))
6796 location_t loc = EXPR_HAS_LOCATION (rhs)
6797 ? EXPR_LOCATION (rhs) : input_location;
6799 warning_at (loc, OPT_Wparentheses,
6800 "suggest parentheses around assignment used as truth value");
6801 TREE_NO_WARNING (rhs) = 1;
6804 return perform_implicit_conversion_flags (strip_top_quals (type), rhs,
6808 /* Convert RHS to be of type TYPE.
6809 If EXP is nonzero, it is the target of the initialization.
6810 ERRTYPE is a string to use in error messages.
6812 Two major differences between the behavior of
6813 `convert_for_assignment' and `convert_for_initialization'
6814 are that references are bashed in the former, while
6815 copied in the latter, and aggregates are assigned in
6816 the former (operator=) while initialized in the
6819 If using constructor make sure no conversion operator exists, if one does
6820 exist, an ambiguity exists.
6822 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6825 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6826 const char *errtype, tree fndecl, int parmnum,
6827 tsubst_flags_t complain)
6829 enum tree_code codel = TREE_CODE (type);
6831 enum tree_code coder;
6833 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6834 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6835 if (TREE_CODE (rhs) == NOP_EXPR
6836 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6837 && codel != REFERENCE_TYPE)
6838 rhs = TREE_OPERAND (rhs, 0);
6840 if (type == error_mark_node
6841 || rhs == error_mark_node
6842 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6843 return error_mark_node;
6845 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6846 && TREE_CODE (type) != ARRAY_TYPE
6847 && (TREE_CODE (type) != REFERENCE_TYPE
6848 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6849 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6850 && (TREE_CODE (type) != REFERENCE_TYPE
6851 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6852 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6853 rhs = decay_conversion (rhs);
6855 rhstype = TREE_TYPE (rhs);
6856 coder = TREE_CODE (rhstype);
6858 if (coder == ERROR_MARK)
6859 return error_mark_node;
6861 /* We accept references to incomplete types, so we can
6862 return here before checking if RHS is of complete type. */
6864 if (codel == REFERENCE_TYPE)
6866 /* This should eventually happen in convert_arguments. */
6867 int savew = 0, savee = 0;
6870 savew = warningcount, savee = errorcount;
6871 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6875 if (warningcount > savew)
6876 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6877 else if (errorcount > savee)
6878 error ("in passing argument %P of %q+D", parmnum, fndecl);
6884 exp = require_complete_type (exp);
6885 if (exp == error_mark_node)
6886 return error_mark_node;
6888 rhstype = non_reference (rhstype);
6890 type = complete_type (type);
6892 if (MAYBE_CLASS_TYPE_P (type))
6893 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6895 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum,
6899 /* If RETVAL is the address of, or a reference to, a local variable or
6900 temporary give an appropriate warning. */
6903 maybe_warn_about_returning_address_of_local (tree retval)
6905 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6906 tree whats_returned = retval;
6910 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6911 whats_returned = TREE_OPERAND (whats_returned, 1);
6912 else if (CONVERT_EXPR_P (whats_returned)
6913 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR)
6914 whats_returned = TREE_OPERAND (whats_returned, 0);
6919 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6921 whats_returned = TREE_OPERAND (whats_returned, 0);
6923 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6925 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6926 || TREE_CODE (whats_returned) == TARGET_EXPR)
6928 warning (0, "returning reference to temporary");
6931 if (TREE_CODE (whats_returned) == VAR_DECL
6932 && DECL_NAME (whats_returned)
6933 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6935 warning (0, "reference to non-lvalue returned");
6940 while (TREE_CODE (whats_returned) == COMPONENT_REF
6941 || TREE_CODE (whats_returned) == ARRAY_REF)
6942 whats_returned = TREE_OPERAND (whats_returned, 0);
6944 if (DECL_P (whats_returned)
6945 && DECL_NAME (whats_returned)
6946 && DECL_FUNCTION_SCOPE_P (whats_returned)
6947 && !(TREE_STATIC (whats_returned)
6948 || TREE_PUBLIC (whats_returned)))
6950 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6951 warning (0, "reference to local variable %q+D returned",
6954 warning (0, "address of local variable %q+D returned",
6960 /* Check that returning RETVAL from the current function is valid.
6961 Return an expression explicitly showing all conversions required to
6962 change RETVAL into the function return type, and to assign it to
6963 the DECL_RESULT for the function. Set *NO_WARNING to true if
6964 code reaches end of non-void function warning shouldn't be issued
6965 on this RETURN_EXPR. */
6968 check_return_expr (tree retval, bool *no_warning)
6971 /* The type actually returned by the function, after any
6974 int fn_returns_value_p;
6975 bool named_return_value_okay_p;
6977 *no_warning = false;
6979 /* A `volatile' function is one that isn't supposed to return, ever.
6980 (This is a G++ extension, used to get better code for functions
6981 that call the `volatile' function.) */
6982 if (TREE_THIS_VOLATILE (current_function_decl))
6983 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6985 /* Check for various simple errors. */
6986 if (DECL_DESTRUCTOR_P (current_function_decl))
6989 error ("returning a value from a destructor");
6992 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6994 if (in_function_try_handler)
6995 /* If a return statement appears in a handler of the
6996 function-try-block of a constructor, the program is ill-formed. */
6997 error ("cannot return from a handler of a function-try-block of a constructor");
6999 /* You can't return a value from a constructor. */
7000 error ("returning a value from a constructor");
7004 if (processing_template_decl)
7006 current_function_returns_value = 1;
7007 if (check_for_bare_parameter_packs (retval))
7008 retval = error_mark_node;
7012 /* When no explicit return-value is given in a function with a named
7013 return value, the named return value is used. */
7014 result = DECL_RESULT (current_function_decl);
7015 valtype = TREE_TYPE (result);
7016 gcc_assert (valtype != NULL_TREE);
7017 fn_returns_value_p = !VOID_TYPE_P (valtype);
7018 if (!retval && DECL_NAME (result) && fn_returns_value_p)
7021 /* Check for a return statement with no return value in a function
7022 that's supposed to return a value. */
7023 if (!retval && fn_returns_value_p)
7025 permerror (input_location, "return-statement with no value, in function returning %qT",
7027 /* Clear this, so finish_function won't say that we reach the
7028 end of a non-void function (which we don't, we gave a
7030 current_function_returns_null = 0;
7031 /* And signal caller that TREE_NO_WARNING should be set on the
7032 RETURN_EXPR to avoid control reaches end of non-void function
7033 warnings in tree-cfg.c. */
7036 /* Check for a return statement with a value in a function that
7037 isn't supposed to return a value. */
7038 else if (retval && !fn_returns_value_p)
7040 if (VOID_TYPE_P (TREE_TYPE (retval)))
7041 /* You can return a `void' value from a function of `void'
7042 type. In that case, we have to evaluate the expression for
7043 its side-effects. */
7044 finish_expr_stmt (retval);
7046 permerror (input_location, "return-statement with a value, in function "
7047 "returning 'void'");
7048 current_function_returns_null = 1;
7050 /* There's really no value to return, after all. */
7054 /* Remember that this function can sometimes return without a
7056 current_function_returns_null = 1;
7058 /* Remember that this function did return a value. */
7059 current_function_returns_value = 1;
7061 /* Check for erroneous operands -- but after giving ourselves a
7062 chance to provide an error about returning a value from a void
7064 if (error_operand_p (retval))
7066 current_function_return_value = error_mark_node;
7067 return error_mark_node;
7070 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
7071 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
7072 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
7073 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
7075 && retval && null_ptr_cst_p (retval))
7076 warning (0, "%<operator new%> must not return NULL unless it is "
7077 "declared %<throw()%> (or -fcheck-new is in effect)");
7079 /* Effective C++ rule 15. See also start_function. */
7081 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
7085 /* The function return type must be a reference to the current
7087 if (TREE_CODE (valtype) == REFERENCE_TYPE
7088 && same_type_ignoring_top_level_qualifiers_p
7089 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
7091 /* Returning '*this' is obviously OK. */
7092 if (retval == current_class_ref)
7094 /* If we are calling a function whose return type is the same of
7095 the current class reference, it is ok. */
7096 else if (TREE_CODE (retval) == INDIRECT_REF
7097 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
7102 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
7105 /* The fabled Named Return Value optimization, as per [class.copy]/15:
7107 [...] For a function with a class return type, if the expression
7108 in the return statement is the name of a local object, and the cv-
7109 unqualified type of the local object is the same as the function
7110 return type, an implementation is permitted to omit creating the tem-
7111 porary object to hold the function return value [...]
7113 So, if this is a value-returning function that always returns the same
7114 local variable, remember it.
7116 It might be nice to be more flexible, and choose the first suitable
7117 variable even if the function sometimes returns something else, but
7118 then we run the risk of clobbering the variable we chose if the other
7119 returned expression uses the chosen variable somehow. And people expect
7120 this restriction, anyway. (jason 2000-11-19)
7122 See finish_function and finalize_nrv for the rest of this optimization. */
7124 named_return_value_okay_p =
7125 (retval != NULL_TREE
7126 /* Must be a local, automatic variable. */
7127 && TREE_CODE (retval) == VAR_DECL
7128 && DECL_CONTEXT (retval) == current_function_decl
7129 && ! TREE_STATIC (retval)
7130 && ! DECL_ANON_UNION_VAR_P (retval)
7131 && (DECL_ALIGN (retval)
7132 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
7133 /* The cv-unqualified type of the returned value must be the
7134 same as the cv-unqualified return type of the
7136 && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))),
7138 (TREE_TYPE (TREE_TYPE (current_function_decl)))))
7139 /* And the returned value must be non-volatile. */
7140 && ! TYPE_VOLATILE (TREE_TYPE (retval)));
7142 if (fn_returns_value_p && flag_elide_constructors)
7144 if (named_return_value_okay_p
7145 && (current_function_return_value == NULL_TREE
7146 || current_function_return_value == retval))
7147 current_function_return_value = retval;
7149 current_function_return_value = error_mark_node;
7152 /* We don't need to do any conversions when there's nothing being
7157 /* Do any required conversions. */
7158 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
7159 /* No conversions are required. */
7163 /* The type the function is declared to return. */
7164 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
7165 int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
7167 /* The functype's return type will have been set to void, if it
7168 was an incomplete type. Just treat this as 'return;' */
7169 if (VOID_TYPE_P (functype))
7170 return error_mark_node;
7172 /* Under C++0x [12.8/16 class.copy], a returned lvalue is sometimes
7173 treated as an rvalue for the purposes of overload resolution to
7174 favor move constructors over copy constructors. */
7175 if ((cxx_dialect != cxx98)
7176 && named_return_value_okay_p
7177 /* The variable must not have the `volatile' qualifier. */
7178 && !(cp_type_quals (TREE_TYPE (retval)) & TYPE_QUAL_VOLATILE)
7179 /* The return type must be a class type. */
7180 && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
7181 flags = flags | LOOKUP_PREFER_RVALUE;
7183 /* First convert the value to the function's return type, then
7184 to the type of return value's location to handle the
7185 case that functype is smaller than the valtype. */
7186 retval = convert_for_initialization
7187 (NULL_TREE, functype, retval, flags, "return", NULL_TREE, 0,
7188 tf_warning_or_error);
7189 retval = convert (valtype, retval);
7191 /* If the conversion failed, treat this just like `return;'. */
7192 if (retval == error_mark_node)
7194 /* We can't initialize a register from a AGGR_INIT_EXPR. */
7195 else if (! cfun->returns_struct
7196 && TREE_CODE (retval) == TARGET_EXPR
7197 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
7198 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
7199 TREE_OPERAND (retval, 0));
7201 maybe_warn_about_returning_address_of_local (retval);
7204 /* Actually copy the value returned into the appropriate location. */
7205 if (retval && retval != result)
7206 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
7212 /* Returns nonzero if the pointer-type FROM can be converted to the
7213 pointer-type TO via a qualification conversion. If CONSTP is -1,
7214 then we return nonzero if the pointers are similar, and the
7215 cv-qualification signature of FROM is a proper subset of that of TO.
7217 If CONSTP is positive, then all outer pointers have been
7221 comp_ptr_ttypes_real (tree to, tree from, int constp)
7223 bool to_more_cv_qualified = false;
7224 bool is_opaque_pointer = false;
7226 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7228 if (TREE_CODE (to) != TREE_CODE (from))
7231 if (TREE_CODE (from) == OFFSET_TYPE
7232 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
7233 TYPE_OFFSET_BASETYPE (to)))
7236 /* Const and volatile mean something different for function types,
7237 so the usual checks are not appropriate. */
7238 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
7240 /* In Objective-C++, some types may have been 'volatilized' by
7241 the compiler for EH; when comparing them here, the volatile
7242 qualification must be ignored. */
7243 bool objc_quals_match = objc_type_quals_match (to, from);
7245 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
7248 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
7252 to_more_cv_qualified = true;
7256 constp &= TYPE_READONLY (to);
7259 if (TREE_CODE (to) == VECTOR_TYPE)
7260 is_opaque_pointer = vector_targets_convertible_p (to, from);
7262 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
7263 return ((constp >= 0 || to_more_cv_qualified)
7264 && (is_opaque_pointer
7265 || same_type_ignoring_top_level_qualifiers_p (to, from)));
7269 /* When comparing, say, char ** to char const **, this function takes
7270 the 'char *' and 'char const *'. Do not pass non-pointer/reference
7271 types to this function. */
7274 comp_ptr_ttypes (tree to, tree from)
7276 return comp_ptr_ttypes_real (to, from, 1);
7279 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
7280 type or inheritance-related types, regardless of cv-quals. */
7283 ptr_reasonably_similar (const_tree to, const_tree from)
7285 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7287 /* Any target type is similar enough to void. */
7288 if (TREE_CODE (to) == VOID_TYPE
7289 || TREE_CODE (from) == VOID_TYPE)
7292 if (TREE_CODE (to) != TREE_CODE (from))
7295 if (TREE_CODE (from) == OFFSET_TYPE
7296 && comptypes (TYPE_OFFSET_BASETYPE (to),
7297 TYPE_OFFSET_BASETYPE (from),
7298 COMPARE_BASE | COMPARE_DERIVED))
7301 if (TREE_CODE (to) == VECTOR_TYPE
7302 && vector_types_convertible_p (to, from, false))
7305 if (TREE_CODE (to) == INTEGER_TYPE
7306 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
7309 if (TREE_CODE (to) == FUNCTION_TYPE)
7312 if (TREE_CODE (to) != POINTER_TYPE)
7314 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
7315 COMPARE_BASE | COMPARE_DERIVED);
7319 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
7320 pointer-to-member types) are the same, ignoring cv-qualification at
7324 comp_ptr_ttypes_const (tree to, tree from)
7326 bool is_opaque_pointer = false;
7328 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7330 if (TREE_CODE (to) != TREE_CODE (from))
7333 if (TREE_CODE (from) == OFFSET_TYPE
7334 && same_type_p (TYPE_OFFSET_BASETYPE (from),
7335 TYPE_OFFSET_BASETYPE (to)))
7338 if (TREE_CODE (to) == VECTOR_TYPE)
7339 is_opaque_pointer = vector_targets_convertible_p (to, from);
7341 if (TREE_CODE (to) != POINTER_TYPE)
7342 return (is_opaque_pointer
7343 || same_type_ignoring_top_level_qualifiers_p (to, from));
7347 /* Returns the type qualifiers for this type, including the qualifiers on the
7348 elements for an array type. */
7351 cp_type_quals (const_tree type)
7353 /* This CONST_CAST is okay because strip_array_types returns its
7354 argument unmodified and we assign it to a const_tree. */
7355 type = strip_array_types (CONST_CAST_TREE(type));
7356 if (type == error_mark_node)
7357 return TYPE_UNQUALIFIED;
7358 return TYPE_QUALS (type);
7361 /* Returns nonzero if the TYPE is const from a C++ perspective: look inside
7365 cp_type_readonly (const_tree type)
7367 /* This CONST_CAST is okay because strip_array_types returns its
7368 argument unmodified and we assign it to a const_tree. */
7369 type = strip_array_types (CONST_CAST_TREE(type));
7370 return TYPE_READONLY (type);
7373 /* Returns nonzero if the TYPE contains a mutable member. */
7376 cp_has_mutable_p (const_tree type)
7378 /* This CONST_CAST is okay because strip_array_types returns its
7379 argument unmodified and we assign it to a const_tree. */
7380 type = strip_array_types (CONST_CAST_TREE(type));
7382 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
7385 /* Set TREE_READONLY and TREE_VOLATILE on DECL as indicated by the
7386 TYPE_QUALS. For a VAR_DECL, this may be an optimistic
7387 approximation. In particular, consider:
7390 struct S { int i; };
7391 const S s = { f(); }
7393 Here, we will make "s" as TREE_READONLY (because it is declared
7394 "const") -- only to reverse ourselves upon seeing that the
7395 initializer is non-constant. */
7398 cp_apply_type_quals_to_decl (int type_quals, tree decl)
7400 tree type = TREE_TYPE (decl);
7402 if (type == error_mark_node)
7405 if (TREE_CODE (decl) == TYPE_DECL)
7408 if (TREE_CODE (type) == FUNCTION_TYPE
7409 && type_quals != TYPE_UNQUALIFIED)
7411 /* This was an error in C++98 (cv-qualifiers cannot be added to
7412 a function type), but DR 295 makes the code well-formed by
7413 dropping the extra qualifiers. */
7416 tree bad_type = build_qualified_type (type, type_quals);
7417 pedwarn (input_location, OPT_pedantic,
7418 "ignoring %qV qualifiers added to function type %qT",
7422 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
7426 /* Avoid setting TREE_READONLY incorrectly. */
7427 if (/* If the object has a constructor, the constructor may modify
7429 TYPE_NEEDS_CONSTRUCTING (type)
7430 /* If the type isn't complete, we don't know yet if it will need
7432 || !COMPLETE_TYPE_P (type)
7433 /* If the type has a mutable component, that component might be
7435 || TYPE_HAS_MUTABLE_P (type))
7436 type_quals &= ~TYPE_QUAL_CONST;
7438 c_apply_type_quals_to_decl (type_quals, decl);
7441 /* Subroutine of casts_away_constness. Make T1 and T2 point at
7442 exemplar types such that casting T1 to T2 is casting away constness
7443 if and only if there is no implicit conversion from T1 to T2. */
7446 casts_away_constness_r (tree *t1, tree *t2)
7451 /* [expr.const.cast]
7453 For multi-level pointer to members and multi-level mixed pointers
7454 and pointers to members (conv.qual), the "member" aspect of a
7455 pointer to member level is ignored when determining if a const
7456 cv-qualifier has been cast away. */
7457 /* [expr.const.cast]
7459 For two pointer types:
7461 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
7462 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
7465 casting from X1 to X2 casts away constness if, for a non-pointer
7466 type T there does not exist an implicit conversion (clause
7469 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
7473 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
7474 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
7475 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
7477 *t1 = cp_build_qualified_type (void_type_node,
7478 cp_type_quals (*t1));
7479 *t2 = cp_build_qualified_type (void_type_node,
7480 cp_type_quals (*t2));
7484 quals1 = cp_type_quals (*t1);
7485 quals2 = cp_type_quals (*t2);
7487 if (TYPE_PTRMEM_P (*t1))
7488 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
7490 *t1 = TREE_TYPE (*t1);
7491 if (TYPE_PTRMEM_P (*t2))
7492 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
7494 *t2 = TREE_TYPE (*t2);
7496 casts_away_constness_r (t1, t2);
7497 *t1 = build_pointer_type (*t1);
7498 *t2 = build_pointer_type (*t2);
7499 *t1 = cp_build_qualified_type (*t1, quals1);
7500 *t2 = cp_build_qualified_type (*t2, quals2);
7503 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
7506 ??? This function returns non-zero if casting away qualifiers not
7507 just const. We would like to return to the caller exactly which
7508 qualifiers are casted away to give more accurate diagnostics.
7512 casts_away_constness (tree t1, tree t2)
7514 if (TREE_CODE (t2) == REFERENCE_TYPE)
7516 /* [expr.const.cast]
7518 Casting from an lvalue of type T1 to an lvalue of type T2
7519 using a reference cast casts away constness if a cast from an
7520 rvalue of type "pointer to T1" to the type "pointer to T2"
7521 casts away constness. */
7522 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
7523 return casts_away_constness (build_pointer_type (t1),
7524 build_pointer_type (TREE_TYPE (t2)));
7527 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
7528 /* [expr.const.cast]
7530 Casting from an rvalue of type "pointer to data member of X
7531 of type T1" to the type "pointer to data member of Y of type
7532 T2" casts away constness if a cast from an rvalue of type
7533 "pointer to T1" to the type "pointer to T2" casts away
7535 return casts_away_constness
7536 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
7537 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
7539 /* Casting away constness is only something that makes sense for
7540 pointer or reference types. */
7541 if (TREE_CODE (t1) != POINTER_TYPE
7542 || TREE_CODE (t2) != POINTER_TYPE)
7545 /* Top-level qualifiers don't matter. */
7546 t1 = TYPE_MAIN_VARIANT (t1);
7547 t2 = TYPE_MAIN_VARIANT (t2);
7548 casts_away_constness_r (&t1, &t2);
7549 if (!can_convert (t2, t1))
7555 /* If T is a REFERENCE_TYPE return the type to which T refers.
7556 Otherwise, return T itself. */
7559 non_reference (tree t)
7561 if (TREE_CODE (t) == REFERENCE_TYPE)
7567 /* Return nonzero if REF is an lvalue valid for this language;
7568 otherwise, print an error message and return zero. USE says
7569 how the lvalue is being used and so selects the error message. */
7572 lvalue_or_else (tree ref, enum lvalue_use use, tsubst_flags_t complain)
7574 int win = lvalue_p (ref);
7576 if (!win && (complain & tf_error))