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_POD_P (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 (COMPONENT_REF, member_type,
2433 ptrmem, member, NULL_TREE);
2436 /* Given an expression PTR for a pointer, return an expression
2437 for the value pointed to.
2438 ERRORSTRING is the name of the operator to appear in error messages.
2440 This function may need to overload OPERATOR_FNNAME.
2441 Must also handle REFERENCE_TYPEs for C++. */
2444 build_x_indirect_ref (tree expr, const char *errorstring,
2445 tsubst_flags_t complain)
2447 tree orig_expr = expr;
2450 if (processing_template_decl)
2452 /* Retain the type if we know the operand is a pointer so that
2453 describable_type doesn't make auto deduction break. */
2454 if (TREE_TYPE (expr) && POINTER_TYPE_P (TREE_TYPE (expr)))
2455 return build_min (INDIRECT_REF, TREE_TYPE (TREE_TYPE (expr)), expr);
2456 if (type_dependent_expression_p (expr))
2457 return build_min_nt (INDIRECT_REF, expr);
2458 expr = build_non_dependent_expr (expr);
2461 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2462 NULL_TREE, /*overloaded_p=*/NULL, complain);
2464 rval = cp_build_indirect_ref (expr, errorstring, complain);
2466 if (processing_template_decl && rval != error_mark_node)
2467 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2472 /* Helper function called from c-common. */
2474 build_indirect_ref (location_t loc __attribute__ ((__unused__)),
2475 tree ptr, const char *errorstring)
2477 return cp_build_indirect_ref (ptr, errorstring, tf_warning_or_error);
2481 cp_build_indirect_ref (tree ptr, const char *errorstring,
2482 tsubst_flags_t complain)
2486 if (ptr == error_mark_node)
2487 return error_mark_node;
2489 if (ptr == current_class_ptr)
2490 return current_class_ref;
2492 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2493 ? ptr : decay_conversion (ptr));
2494 type = TREE_TYPE (pointer);
2496 if (POINTER_TYPE_P (type))
2500 If the type of the expression is "pointer to T," the type
2501 of the result is "T." */
2502 tree t = TREE_TYPE (type);
2504 if (CONVERT_EXPR_P (ptr)
2505 || TREE_CODE (ptr) == VIEW_CONVERT_EXPR)
2507 /* If a warning is issued, mark it to avoid duplicates from
2508 the backend. This only needs to be done at
2509 warn_strict_aliasing > 2. */
2510 if (warn_strict_aliasing > 2)
2511 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (ptr, 0)),
2512 type, TREE_OPERAND (ptr, 0)))
2513 TREE_NO_WARNING (ptr) = 1;
2516 if (VOID_TYPE_P (t))
2518 /* A pointer to incomplete type (other than cv void) can be
2519 dereferenced [expr.unary.op]/1 */
2520 if (complain & tf_error)
2521 error ("%qT is not a pointer-to-object type", type);
2522 return error_mark_node;
2524 else if (TREE_CODE (pointer) == ADDR_EXPR
2525 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2526 /* The POINTER was something like `&x'. We simplify `*&x' to
2528 return TREE_OPERAND (pointer, 0);
2531 tree ref = build1 (INDIRECT_REF, t, pointer);
2533 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2534 so that we get the proper error message if the result is used
2535 to assign to. Also, &* is supposed to be a no-op. */
2536 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2537 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2538 TREE_SIDE_EFFECTS (ref)
2539 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2543 else if (!(complain & tf_error))
2544 /* Don't emit any errors; we'll just return ERROR_MARK_NODE later. */
2546 /* `pointer' won't be an error_mark_node if we were given a
2547 pointer to member, so it's cool to check for this here. */
2548 else if (TYPE_PTR_TO_MEMBER_P (type))
2549 error ("invalid use of %qs on pointer to member", errorstring);
2550 else if (pointer != error_mark_node)
2553 error ("invalid type argument of %qs", errorstring);
2555 error ("invalid type argument");
2557 return error_mark_node;
2560 /* This handles expressions of the form "a[i]", which denotes
2563 This is logically equivalent in C to *(a+i), but we may do it differently.
2564 If A is a variable or a member, we generate a primitive ARRAY_REF.
2565 This avoids forcing the array out of registers, and can work on
2566 arrays that are not lvalues (for example, members of structures returned
2569 If INDEX is of some user-defined type, it must be converted to
2570 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2571 will inherit the type of the array, which will be some pointer type.
2573 LOC is the location to use in building the array reference. */
2576 build_array_ref (location_t loc, tree array, tree idx)
2582 error_at (loc, "subscript missing in array reference");
2583 return error_mark_node;
2586 if (TREE_TYPE (array) == error_mark_node
2587 || TREE_TYPE (idx) == error_mark_node)
2588 return error_mark_node;
2590 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2592 switch (TREE_CODE (array))
2596 tree value = build_array_ref (loc, TREE_OPERAND (array, 1), idx);
2597 ret = build2 (COMPOUND_EXPR, TREE_TYPE (value),
2598 TREE_OPERAND (array, 0), value);
2599 SET_EXPR_LOCATION (ret, loc);
2604 ret = build_conditional_expr
2605 (TREE_OPERAND (array, 0),
2606 build_array_ref (loc, TREE_OPERAND (array, 1), idx),
2607 build_array_ref (loc, TREE_OPERAND (array, 2), idx),
2608 tf_warning_or_error);
2609 protected_set_expr_location (ret, loc);
2616 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2620 warn_array_subscript_with_type_char (idx);
2622 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2624 error_at (loc, "array subscript is not an integer");
2625 return error_mark_node;
2628 /* Apply integral promotions *after* noticing character types.
2629 (It is unclear why we do these promotions -- the standard
2630 does not say that we should. In fact, the natural thing would
2631 seem to be to convert IDX to ptrdiff_t; we're performing
2632 pointer arithmetic.) */
2633 idx = perform_integral_promotions (idx);
2635 /* An array that is indexed by a non-constant
2636 cannot be stored in a register; we must be able to do
2637 address arithmetic on its address.
2638 Likewise an array of elements of variable size. */
2639 if (TREE_CODE (idx) != INTEGER_CST
2640 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2641 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2644 if (!cxx_mark_addressable (array))
2645 return error_mark_node;
2648 /* An array that is indexed by a constant value which is not within
2649 the array bounds cannot be stored in a register either; because we
2650 would get a crash in store_bit_field/extract_bit_field when trying
2651 to access a non-existent part of the register. */
2652 if (TREE_CODE (idx) == INTEGER_CST
2653 && TYPE_DOMAIN (TREE_TYPE (array))
2654 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2656 if (!cxx_mark_addressable (array))
2657 return error_mark_node;
2660 if (!lvalue_p (array))
2661 pedwarn (loc, OPT_pedantic,
2662 "ISO C++ forbids subscripting non-lvalue array");
2664 /* Note in C++ it is valid to subscript a `register' array, since
2665 it is valid to take the address of something with that
2666 storage specification. */
2670 while (TREE_CODE (foo) == COMPONENT_REF)
2671 foo = TREE_OPERAND (foo, 0);
2672 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2673 warning_at (loc, OPT_Wextra,
2674 "subscripting array declared %<register%>");
2677 type = TREE_TYPE (TREE_TYPE (array));
2678 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2679 /* Array ref is const/volatile if the array elements are
2680 or if the array is.. */
2681 TREE_READONLY (rval)
2682 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2683 TREE_SIDE_EFFECTS (rval)
2684 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2685 TREE_THIS_VOLATILE (rval)
2686 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2687 ret = require_complete_type (fold_if_not_in_template (rval));
2688 protected_set_expr_location (ret, loc);
2693 tree ar = default_conversion (array);
2694 tree ind = default_conversion (idx);
2696 /* Put the integer in IND to simplify error checking. */
2697 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2704 if (ar == error_mark_node)
2707 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2709 error_at (loc, "subscripted value is neither array nor pointer");
2710 return error_mark_node;
2712 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2714 error_at (loc, "array subscript is not an integer");
2715 return error_mark_node;
2718 warn_array_subscript_with_type_char (idx);
2720 ret = cp_build_indirect_ref (cp_build_binary_op (input_location,
2722 tf_warning_or_error),
2724 tf_warning_or_error);
2725 protected_set_expr_location (ret, loc);
2730 /* Resolve a pointer to member function. INSTANCE is the object
2731 instance to use, if the member points to a virtual member.
2733 This used to avoid checking for virtual functions if basetype
2734 has no virtual functions, according to an earlier ANSI draft.
2735 With the final ISO C++ rules, such an optimization is
2736 incorrect: A pointer to a derived member can be static_cast
2737 to pointer-to-base-member, as long as the dynamic object
2738 later has the right member. */
2741 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2743 if (TREE_CODE (function) == OFFSET_REF)
2744 function = TREE_OPERAND (function, 1);
2746 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2748 tree idx, delta, e1, e2, e3, vtbl, basetype;
2749 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2751 tree instance_ptr = *instance_ptrptr;
2752 tree instance_save_expr = 0;
2753 if (instance_ptr == error_mark_node)
2755 if (TREE_CODE (function) == PTRMEM_CST)
2757 /* Extracting the function address from a pmf is only
2758 allowed with -Wno-pmf-conversions. It only works for
2760 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2761 e1 = convert (fntype, e1);
2766 error ("object missing in use of %qE", function);
2767 return error_mark_node;
2771 if (TREE_SIDE_EFFECTS (instance_ptr))
2772 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2774 if (TREE_SIDE_EFFECTS (function))
2775 function = save_expr (function);
2777 /* Start by extracting all the information from the PMF itself. */
2778 e3 = pfn_from_ptrmemfunc (function);
2779 delta = delta_from_ptrmemfunc (function);
2780 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2781 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2783 case ptrmemfunc_vbit_in_pfn:
2784 e1 = cp_build_binary_op (input_location,
2785 BIT_AND_EXPR, idx, integer_one_node,
2786 tf_warning_or_error);
2787 idx = cp_build_binary_op (input_location,
2788 MINUS_EXPR, idx, integer_one_node,
2789 tf_warning_or_error);
2792 case ptrmemfunc_vbit_in_delta:
2793 e1 = cp_build_binary_op (input_location,
2794 BIT_AND_EXPR, delta, integer_one_node,
2795 tf_warning_or_error);
2796 delta = cp_build_binary_op (input_location,
2797 RSHIFT_EXPR, delta, integer_one_node,
2798 tf_warning_or_error);
2805 /* Convert down to the right base before using the instance. A
2806 special case is that in a pointer to member of class C, C may
2807 be incomplete. In that case, the function will of course be
2808 a member of C, and no conversion is required. In fact,
2809 lookup_base will fail in that case, because incomplete
2810 classes do not have BINFOs. */
2811 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2812 if (!same_type_ignoring_top_level_qualifiers_p
2813 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2815 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2816 basetype, ba_check, NULL);
2817 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2819 if (instance_ptr == error_mark_node)
2820 return error_mark_node;
2822 /* ...and then the delta in the PMF. */
2823 instance_ptr = build2 (POINTER_PLUS_EXPR, TREE_TYPE (instance_ptr),
2824 instance_ptr, fold_convert (sizetype, delta));
2826 /* Hand back the adjusted 'this' argument to our caller. */
2827 *instance_ptrptr = instance_ptr;
2829 /* Next extract the vtable pointer from the object. */
2830 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2832 vtbl = cp_build_indirect_ref (vtbl, NULL, tf_warning_or_error);
2833 /* If the object is not dynamic the access invokes undefined
2834 behavior. As it is not executed in this case silence the
2835 spurious warnings it may provoke. */
2836 TREE_NO_WARNING (vtbl) = 1;
2838 /* Finally, extract the function pointer from the vtable. */
2839 e2 = fold_build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl,
2840 fold_convert (sizetype, idx));
2841 e2 = cp_build_indirect_ref (e2, NULL, tf_warning_or_error);
2842 TREE_CONSTANT (e2) = 1;
2844 /* When using function descriptors, the address of the
2845 vtable entry is treated as a function pointer. */
2846 if (TARGET_VTABLE_USES_DESCRIPTORS)
2847 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2848 cp_build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1,
2849 tf_warning_or_error));
2851 e2 = fold_convert (TREE_TYPE (e3), e2);
2852 e1 = build_conditional_expr (e1, e2, e3, tf_warning_or_error);
2854 /* Make sure this doesn't get evaluated first inside one of the
2855 branches of the COND_EXPR. */
2856 if (instance_save_expr)
2857 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2858 instance_save_expr, e1);
2865 /* Used by the C-common bits. */
2867 build_function_call (location_t loc ATTRIBUTE_UNUSED,
2868 tree function, tree params)
2870 return cp_build_function_call (function, params, tf_warning_or_error);
2873 /* Used by the C-common bits. */
2875 build_function_call_vec (location_t loc ATTRIBUTE_UNUSED,
2876 tree function, VEC(tree,gc) *params,
2877 VEC(tree,gc) *origtypes ATTRIBUTE_UNUSED)
2879 VEC(tree,gc) *orig_params = params;
2880 tree ret = cp_build_function_call_vec (function, ¶ms,
2881 tf_warning_or_error);
2883 /* cp_build_function_call_vec can reallocate PARAMS by adding
2884 default arguments. That should never happen here. Verify
2886 gcc_assert (params == orig_params);
2891 /* Build a function call using a tree list of arguments. */
2894 cp_build_function_call (tree function, tree params, tsubst_flags_t complain)
2899 vec = make_tree_vector ();
2900 for (; params != NULL_TREE; params = TREE_CHAIN (params))
2901 VEC_safe_push (tree, gc, vec, TREE_VALUE (params));
2902 ret = cp_build_function_call_vec (function, &vec, complain);
2903 release_tree_vector (vec);
2907 /* Build a function call using a vector of arguments. PARAMS may be
2908 NULL if there are no parameters. This changes the contents of
2912 cp_build_function_call_vec (tree function, VEC(tree,gc) **params,
2913 tsubst_flags_t complain)
2915 tree fntype, fndecl;
2916 tree name = NULL_TREE;
2918 tree original = function;
2922 VEC(tree,gc) *allocated = NULL;
2925 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2926 expressions, like those used for ObjC messenger dispatches. */
2927 if (params != NULL && !VEC_empty (tree, *params))
2928 function = objc_rewrite_function_call (function,
2929 VEC_index (tree, *params, 0));
2931 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2932 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2933 if (TREE_CODE (function) == NOP_EXPR
2934 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2935 function = TREE_OPERAND (function, 0);
2937 if (TREE_CODE (function) == FUNCTION_DECL)
2939 name = DECL_NAME (function);
2941 mark_used (function);
2944 /* Convert anything with function type to a pointer-to-function. */
2945 if (DECL_MAIN_P (function) && (complain & tf_error))
2946 pedwarn (input_location, OPT_pedantic,
2947 "ISO C++ forbids calling %<::main%> from within program");
2949 function = build_addr_func (function);
2955 function = build_addr_func (function);
2958 if (function == error_mark_node)
2959 return error_mark_node;
2961 fntype = TREE_TYPE (function);
2963 if (TYPE_PTRMEMFUNC_P (fntype))
2965 if (complain & tf_error)
2966 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2967 "function in %<%E (...)%>, e.g. %<(... ->* %E) (...)%>",
2968 original, original);
2969 return error_mark_node;
2972 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2973 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2975 if (!((TREE_CODE (fntype) == POINTER_TYPE
2976 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2978 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2980 if (complain & tf_error)
2981 error ("%qE cannot be used as a function", original);
2982 return error_mark_node;
2985 /* fntype now gets the type of function pointed to. */
2986 fntype = TREE_TYPE (fntype);
2987 parm_types = TYPE_ARG_TYPES (fntype);
2991 allocated = make_tree_vector ();
2992 params = &allocated;
2995 nargs = convert_arguments (parm_types, params, fndecl, LOOKUP_NORMAL,
2998 return error_mark_node;
3000 argarray = VEC_address (tree, *params);
3002 /* Check for errors in format strings and inappropriately
3004 check_function_arguments (TYPE_ATTRIBUTES (fntype), nargs, argarray,
3007 ret = build_cxx_call (function, nargs, argarray);
3009 if (allocated != NULL)
3010 release_tree_vector (allocated);
3015 /* Convert the actual parameter expressions in the list VALUES to the
3016 types in the list TYPELIST. The converted expressions are stored
3017 back in the VALUES vector.
3018 If parmdecls is exhausted, or when an element has NULL as its type,
3019 perform the default conversions.
3021 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
3023 This is also where warnings about wrong number of args are generated.
3025 Returns the actual number of arguments processed (which might be less
3026 than the length of the vector), or -1 on error.
3028 In C++, unspecified trailing parameters can be filled in with their
3029 default arguments, if such were specified. Do so here. */
3032 convert_arguments (tree typelist, VEC(tree,gc) **values, tree fndecl,
3033 int flags, tsubst_flags_t complain)
3036 const char *called_thing = 0;
3039 /* Argument passing is always copy-initialization. */
3040 flags |= LOOKUP_ONLYCONVERTING;
3044 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
3046 if (DECL_NAME (fndecl) == NULL_TREE
3047 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
3048 called_thing = "constructor";
3050 called_thing = "member function";
3053 called_thing = "function";
3056 for (i = 0, typetail = typelist;
3057 i < VEC_length (tree, *values);
3060 tree type = typetail ? TREE_VALUE (typetail) : 0;
3061 tree val = VEC_index (tree, *values, i);
3063 if (val == error_mark_node || type == error_mark_node)
3066 if (type == void_type_node)
3068 if (complain & tf_error)
3072 error ("too many arguments to %s %q+#D",
3073 called_thing, fndecl);
3074 error ("at this point in file");
3077 error ("too many arguments to function");
3084 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3085 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
3086 if (TREE_CODE (val) == NOP_EXPR
3087 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
3088 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
3089 val = TREE_OPERAND (val, 0);
3091 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
3093 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
3094 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
3095 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
3096 val = decay_conversion (val);
3099 if (val == error_mark_node)
3104 /* Formal parm type is specified by a function prototype. */
3107 if (!COMPLETE_TYPE_P (complete_type (type)))
3109 if (complain & tf_error)
3112 error ("parameter %P of %qD has incomplete type %qT",
3115 error ("parameter %P has incomplete type %qT", i, type);
3117 parmval = error_mark_node;
3121 parmval = convert_for_initialization
3122 (NULL_TREE, type, val, flags,
3123 "argument passing", fndecl, i, complain);
3124 parmval = convert_for_arg_passing (type, parmval);
3127 if (parmval == error_mark_node)
3130 VEC_replace (tree, *values, i, parmval);
3134 if (fndecl && DECL_BUILT_IN (fndecl)
3135 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
3136 /* Don't do ellipsis conversion for __built_in_constant_p
3137 as this will result in spurious warnings for non-POD
3139 val = require_complete_type (val);
3141 val = convert_arg_to_ellipsis (val);
3143 VEC_replace (tree, *values, i, val);
3147 typetail = TREE_CHAIN (typetail);
3150 if (typetail != 0 && typetail != void_list_node)
3152 /* See if there are default arguments that can be used. Because
3153 we hold default arguments in the FUNCTION_TYPE (which is so
3154 wrong), we can see default parameters here from deduced
3155 contexts (and via typeof) for indirect function calls.
3156 Fortunately we know whether we have a function decl to
3157 provide default arguments in a language conformant
3159 if (fndecl && TREE_PURPOSE (typetail)
3160 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
3162 for (; typetail != void_list_node; ++i)
3165 = convert_default_arg (TREE_VALUE (typetail),
3166 TREE_PURPOSE (typetail),
3169 if (parmval == error_mark_node)
3172 VEC_safe_push (tree, gc, *values, parmval);
3173 typetail = TREE_CHAIN (typetail);
3174 /* ends with `...'. */
3175 if (typetail == NULL_TREE)
3181 if (complain & tf_error)
3185 error ("too few arguments to %s %q+#D",
3186 called_thing, fndecl);
3187 error ("at this point in file");
3190 error ("too few arguments to function");
3199 /* Build a binary-operation expression, after performing default
3200 conversions on the operands. CODE is the kind of expression to
3201 build. ARG1 and ARG2 are the arguments. ARG1_CODE and ARG2_CODE
3202 are the tree codes which correspond to ARG1 and ARG2 when issuing
3203 warnings about possibly misplaced parentheses. They may differ
3204 from the TREE_CODE of ARG1 and ARG2 if the parser has done constant
3205 folding (e.g., if the parser sees "a | 1 + 1", it may call this
3206 routine with ARG2 being an INTEGER_CST and ARG2_CODE == PLUS_EXPR).
3207 To avoid issuing any parentheses warnings, pass ARG1_CODE and/or
3208 ARG2_CODE as ERROR_MARK. */
3211 build_x_binary_op (enum tree_code code, tree arg1, enum tree_code arg1_code,
3212 tree arg2, enum tree_code arg2_code, bool *overloaded_p,
3213 tsubst_flags_t complain)
3222 if (processing_template_decl)
3224 if (type_dependent_expression_p (arg1)
3225 || type_dependent_expression_p (arg2))
3226 return build_min_nt (code, arg1, arg2);
3227 arg1 = build_non_dependent_expr (arg1);
3228 arg2 = build_non_dependent_expr (arg2);
3231 if (code == DOTSTAR_EXPR)
3232 expr = build_m_component_ref (arg1, arg2);
3234 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3235 overloaded_p, complain);
3237 /* Check for cases such as x+y<<z which users are likely to
3238 misinterpret. But don't warn about obj << x + y, since that is a
3239 common idiom for I/O. */
3240 if (warn_parentheses
3241 && !processing_template_decl
3242 && !error_operand_p (arg1)
3243 && !error_operand_p (arg2)
3244 && (code != LSHIFT_EXPR
3245 || !CLASS_TYPE_P (TREE_TYPE (arg1))))
3246 warn_about_parentheses (code, arg1_code, orig_arg1, arg2_code, orig_arg2);
3248 if (processing_template_decl && expr != error_mark_node)
3249 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
3254 /* Build and return an ARRAY_REF expression. */
3257 build_x_array_ref (tree arg1, tree arg2, tsubst_flags_t complain)
3259 tree orig_arg1 = arg1;
3260 tree orig_arg2 = arg2;
3263 if (processing_template_decl)
3265 if (type_dependent_expression_p (arg1)
3266 || type_dependent_expression_p (arg2))
3267 return build_min_nt (ARRAY_REF, arg1, arg2,
3268 NULL_TREE, NULL_TREE);
3269 arg1 = build_non_dependent_expr (arg1);
3270 arg2 = build_non_dependent_expr (arg2);
3273 expr = build_new_op (ARRAY_REF, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3274 /*overloaded_p=*/NULL, complain);
3276 if (processing_template_decl && expr != error_mark_node)
3277 return build_min_non_dep (ARRAY_REF, expr, orig_arg1, orig_arg2,
3278 NULL_TREE, NULL_TREE);
3282 /* For the c-common bits. */
3284 build_binary_op (location_t location, enum tree_code code, tree op0, tree op1,
3285 int convert_p ATTRIBUTE_UNUSED)
3287 return cp_build_binary_op (location, code, op0, op1, tf_warning_or_error);
3291 /* Build a binary-operation expression without default conversions.
3292 CODE is the kind of expression to build.
3293 LOCATION is the location_t of the operator in the source code.
3294 This function differs from `build' in several ways:
3295 the data type of the result is computed and recorded in it,
3296 warnings are generated if arg data types are invalid,
3297 special handling for addition and subtraction of pointers is known,
3298 and some optimization is done (operations on narrow ints
3299 are done in the narrower type when that gives the same result).
3300 Constant folding is also done before the result is returned.
3302 Note that the operands will never have enumeral types
3303 because either they have just had the default conversions performed
3304 or they have both just been converted to some other type in which
3305 the arithmetic is to be done.
3307 C++: must do special pointer arithmetic when implementing
3308 multiple inheritance, and deal with pointer to member functions. */
3311 cp_build_binary_op (location_t location,
3312 enum tree_code code, tree orig_op0, tree orig_op1,
3313 tsubst_flags_t complain)
3316 enum tree_code code0, code1;
3318 const char *invalid_op_diag;
3320 /* Expression code to give to the expression when it is built.
3321 Normally this is CODE, which is what the caller asked for,
3322 but in some special cases we change it. */
3323 enum tree_code resultcode = code;
3325 /* Data type in which the computation is to be performed.
3326 In the simplest cases this is the common type of the arguments. */
3327 tree result_type = NULL;
3329 /* Nonzero means operands have already been type-converted
3330 in whatever way is necessary.
3331 Zero means they need to be converted to RESULT_TYPE. */
3334 /* Nonzero means create the expression with this type, rather than
3336 tree build_type = 0;
3338 /* Nonzero means after finally constructing the expression
3339 convert it to this type. */
3340 tree final_type = 0;
3344 /* Nonzero if this is an operation like MIN or MAX which can
3345 safely be computed in short if both args are promoted shorts.
3346 Also implies COMMON.
3347 -1 indicates a bitwise operation; this makes a difference
3348 in the exact conditions for when it is safe to do the operation
3349 in a narrower mode. */
3352 /* Nonzero if this is a comparison operation;
3353 if both args are promoted shorts, compare the original shorts.
3354 Also implies COMMON. */
3355 int short_compare = 0;
3357 /* Nonzero means set RESULT_TYPE to the common type of the args. */
3360 /* True if both operands have arithmetic type. */
3361 bool arithmetic_types_p;
3363 /* Apply default conversions. */
3367 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
3368 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
3369 || code == TRUTH_XOR_EXPR)
3371 if (!really_overloaded_fn (op0))
3372 op0 = decay_conversion (op0);
3373 if (!really_overloaded_fn (op1))
3374 op1 = decay_conversion (op1);
3378 if (!really_overloaded_fn (op0))
3379 op0 = default_conversion (op0);
3380 if (!really_overloaded_fn (op1))
3381 op1 = default_conversion (op1);
3384 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3385 STRIP_TYPE_NOPS (op0);
3386 STRIP_TYPE_NOPS (op1);
3388 /* DTRT if one side is an overloaded function, but complain about it. */
3389 if (type_unknown_p (op0))
3391 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3392 if (t != error_mark_node)
3394 if (complain & tf_error)
3395 permerror (input_location, "assuming cast to type %qT from overloaded function",
3400 if (type_unknown_p (op1))
3402 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3403 if (t != error_mark_node)
3405 if (complain & tf_error)
3406 permerror (input_location, "assuming cast to type %qT from overloaded function",
3412 type0 = TREE_TYPE (op0);
3413 type1 = TREE_TYPE (op1);
3415 /* The expression codes of the data types of the arguments tell us
3416 whether the arguments are integers, floating, pointers, etc. */
3417 code0 = TREE_CODE (type0);
3418 code1 = TREE_CODE (type1);
3420 /* If an error was already reported for one of the arguments,
3421 avoid reporting another error. */
3423 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3424 return error_mark_node;
3426 if ((invalid_op_diag
3427 = targetm.invalid_binary_op (code, type0, type1)))
3429 error (invalid_op_diag);
3430 return error_mark_node;
3436 /* Subtraction of two similar pointers.
3437 We must subtract them as integers, then divide by object size. */
3438 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3439 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3441 return pointer_diff (op0, op1, common_pointer_type (type0, type1));
3442 /* In all other cases except pointer - int, the usual arithmetic
3444 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
3449 /* The pointer - int case is just like pointer + int; fall
3452 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
3453 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
3457 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
3458 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
3459 if (processing_template_decl)
3461 result_type = TREE_TYPE (ptr_operand);
3464 return cp_pointer_int_sum (code,
3475 case TRUNC_DIV_EXPR:
3477 case FLOOR_DIV_EXPR:
3478 case ROUND_DIV_EXPR:
3479 case EXACT_DIV_EXPR:
3480 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3481 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3482 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3483 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3485 enum tree_code tcode0 = code0, tcode1 = code1;
3487 warn_for_div_by_zero (location, op1);
3489 if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE)
3490 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3491 if (tcode1 == COMPLEX_TYPE || tcode1 == VECTOR_TYPE)
3492 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3494 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
3495 resultcode = RDIV_EXPR;
3497 /* When dividing two signed integers, we have to promote to int.
3498 unless we divide by a constant != -1. Note that default
3499 conversion will have been performed on the operands at this
3500 point, so we have to dig out the original type to find out if
3502 shorten = ((TREE_CODE (op0) == NOP_EXPR
3503 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3504 || (TREE_CODE (op1) == INTEGER_CST
3505 && ! integer_all_onesp (op1)));
3514 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3515 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3516 && !VECTOR_FLOAT_TYPE_P (type0)
3517 && !VECTOR_FLOAT_TYPE_P (type1)))
3521 case TRUNC_MOD_EXPR:
3522 case FLOOR_MOD_EXPR:
3523 warn_for_div_by_zero (location, op1);
3525 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3526 && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE
3527 && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE)
3529 else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3531 /* Although it would be tempting to shorten always here, that loses
3532 on some targets, since the modulo instruction is undefined if the
3533 quotient can't be represented in the computation mode. We shorten
3534 only if unsigned or if dividing by something we know != -1. */
3535 shorten = ((TREE_CODE (op0) == NOP_EXPR
3536 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3537 || (TREE_CODE (op1) == INTEGER_CST
3538 && ! integer_all_onesp (op1)));
3543 case TRUTH_ANDIF_EXPR:
3544 case TRUTH_ORIF_EXPR:
3545 case TRUTH_AND_EXPR:
3547 result_type = boolean_type_node;
3550 /* Shift operations: result has same type as first operand;
3551 always convert second operand to int.
3552 Also set SHORT_SHIFT if shifting rightward. */
3555 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3557 result_type = type0;
3558 if (TREE_CODE (op1) == INTEGER_CST)
3560 if (tree_int_cst_lt (op1, integer_zero_node))
3562 if ((complain & tf_warning)
3563 && c_inhibit_evaluation_warnings == 0)
3564 warning (0, "right shift count is negative");
3568 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0
3569 && (complain & tf_warning)
3570 && c_inhibit_evaluation_warnings == 0)
3571 warning (0, "right shift count >= width of type");
3574 /* Convert the shift-count to an integer, regardless of
3575 size of value being shifted. */
3576 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3577 op1 = cp_convert (integer_type_node, op1);
3578 /* Avoid converting op1 to result_type later. */
3584 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3586 result_type = type0;
3587 if (TREE_CODE (op1) == INTEGER_CST)
3589 if (tree_int_cst_lt (op1, integer_zero_node))
3591 if ((complain & tf_warning)
3592 && c_inhibit_evaluation_warnings == 0)
3593 warning (0, "left shift count is negative");
3595 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3597 if ((complain & tf_warning)
3598 && c_inhibit_evaluation_warnings == 0)
3599 warning (0, "left shift count >= width of type");
3602 /* Convert the shift-count to an integer, regardless of
3603 size of value being shifted. */
3604 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3605 op1 = cp_convert (integer_type_node, op1);
3606 /* Avoid converting op1 to result_type later. */
3613 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3615 result_type = type0;
3616 if (TREE_CODE (op1) == INTEGER_CST)
3618 if (tree_int_cst_lt (op1, integer_zero_node))
3620 if (complain & tf_warning)
3621 warning (0, (code == LROTATE_EXPR)
3622 ? G_("left rotate count is negative")
3623 : G_("right rotate count is negative"));
3625 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3627 if (complain & tf_warning)
3628 warning (0, (code == LROTATE_EXPR)
3629 ? G_("left rotate count >= width of type")
3630 : G_("right rotate count >= width of type"));
3633 /* Convert the shift-count to an integer, regardless of
3634 size of value being shifted. */
3635 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3636 op1 = cp_convert (integer_type_node, op1);
3642 if ((complain & tf_warning)
3643 && (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1)))
3644 warning (OPT_Wfloat_equal,
3645 "comparing floating point with == or != is unsafe");
3646 if ((complain & tf_warning)
3647 && ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3648 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0))))
3649 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3651 build_type = boolean_type_node;
3652 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3653 || code0 == COMPLEX_TYPE || code0 == ENUMERAL_TYPE)
3654 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3655 || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE))
3657 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3658 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3659 result_type = composite_pointer_type (type0, type1, op0, op1,
3660 "comparison", complain);
3661 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3662 && null_ptr_cst_p (op1))
3664 if (TREE_CODE (op0) == ADDR_EXPR
3665 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
3667 if (complain & tf_warning)
3668 warning (OPT_Waddress, "the address of %qD will never be NULL",
3669 TREE_OPERAND (op0, 0));
3671 result_type = type0;
3673 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3674 && null_ptr_cst_p (op0))
3676 if (TREE_CODE (op1) == ADDR_EXPR
3677 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
3679 if (complain & tf_warning)
3680 warning (OPT_Waddress, "the address of %qD will never be NULL",
3681 TREE_OPERAND (op1, 0));
3683 result_type = type1;
3685 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3687 result_type = type0;
3688 if (complain & tf_error)
3689 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3691 return error_mark_node;
3693 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3695 result_type = type1;
3696 if (complain & tf_error)
3697 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3699 return error_mark_node;
3701 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3703 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3704 == ptrmemfunc_vbit_in_delta)
3706 tree pfn0 = pfn_from_ptrmemfunc (op0);
3707 tree delta0 = delta_from_ptrmemfunc (op0);
3708 tree e1 = cp_build_binary_op (location,
3711 fold_convert (TREE_TYPE (pfn0),
3714 tree e2 = cp_build_binary_op (location,
3719 e2 = cp_build_binary_op (location,
3720 EQ_EXPR, e2, integer_zero_node,
3722 op0 = cp_build_binary_op (location,
3723 TRUTH_ANDIF_EXPR, e1, e2,
3725 op1 = cp_convert (TREE_TYPE (op0), integer_one_node);
3729 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3730 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3732 result_type = TREE_TYPE (op0);
3734 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3735 return cp_build_binary_op (location, code, op1, op0, complain);
3736 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1))
3739 /* E will be the final comparison. */
3741 /* E1 and E2 are for scratch. */
3749 type = composite_pointer_type (type0, type1, op0, op1, "comparison",
3752 if (!same_type_p (TREE_TYPE (op0), type))
3753 op0 = cp_convert_and_check (type, op0);
3754 if (!same_type_p (TREE_TYPE (op1), type))
3755 op1 = cp_convert_and_check (type, op1);
3757 if (op0 == error_mark_node || op1 == error_mark_node)
3758 return error_mark_node;
3760 if (TREE_SIDE_EFFECTS (op0))
3761 op0 = save_expr (op0);
3762 if (TREE_SIDE_EFFECTS (op1))
3763 op1 = save_expr (op1);
3765 pfn0 = pfn_from_ptrmemfunc (op0);
3766 pfn1 = pfn_from_ptrmemfunc (op1);
3767 delta0 = delta_from_ptrmemfunc (op0);
3768 delta1 = delta_from_ptrmemfunc (op1);
3769 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3770 == ptrmemfunc_vbit_in_delta)
3775 && ((op0.delta == op1.delta)
3776 || (!op0.pfn && op0.delta & 1 == 0
3777 && op1.delta & 1 == 0))
3779 The reason for the `!op0.pfn' bit is that a NULL
3780 pointer-to-member is any member with a zero PFN and
3781 LSB of the DELTA field is 0. */
3783 e1 = cp_build_binary_op (location, BIT_AND_EXPR,
3787 e1 = cp_build_binary_op (location,
3788 EQ_EXPR, e1, integer_zero_node,
3790 e2 = cp_build_binary_op (location, BIT_AND_EXPR,
3794 e2 = cp_build_binary_op (location,
3795 EQ_EXPR, e2, integer_zero_node,
3797 e1 = cp_build_binary_op (location,
3798 TRUTH_ANDIF_EXPR, e2, e1,
3800 e2 = cp_build_binary_op (location, EQ_EXPR,
3802 fold_convert (TREE_TYPE (pfn0),
3805 e2 = cp_build_binary_op (location,
3806 TRUTH_ANDIF_EXPR, e2, e1, complain);
3807 e1 = cp_build_binary_op (location,
3808 EQ_EXPR, delta0, delta1, complain);
3809 e1 = cp_build_binary_op (location,
3810 TRUTH_ORIF_EXPR, e1, e2, complain);
3817 && (!op0.pfn || op0.delta == op1.delta))
3819 The reason for the `!op0.pfn' bit is that a NULL
3820 pointer-to-member is any member with a zero PFN; the
3821 DELTA field is unspecified. */
3823 e1 = cp_build_binary_op (location,
3824 EQ_EXPR, delta0, delta1, complain);
3825 e2 = cp_build_binary_op (location,
3828 fold_convert (TREE_TYPE (pfn0),
3831 e1 = cp_build_binary_op (location,
3832 TRUTH_ORIF_EXPR, e1, e2, complain);
3834 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3835 e = cp_build_binary_op (location,
3836 TRUTH_ANDIF_EXPR, e2, e1, complain);
3837 if (code == EQ_EXPR)
3839 return cp_build_binary_op (location,
3840 EQ_EXPR, e, integer_zero_node, complain);
3844 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3845 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3847 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3848 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3856 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3857 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3859 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3860 result_type = composite_pointer_type (type0, type1, op0, op1,
3861 "comparison", complain);
3868 if (TREE_CODE (orig_op0) == STRING_CST
3869 || TREE_CODE (orig_op1) == STRING_CST)
3871 if (complain & tf_warning)
3872 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3875 build_type = boolean_type_node;
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);
3882 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3883 && integer_zerop (op1))
3884 result_type = type0;
3885 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3886 && integer_zerop (op0))
3887 result_type = type1;
3888 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3890 result_type = type0;
3891 if (complain & tf_error)
3892 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3894 return error_mark_node;
3896 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3898 result_type = type1;
3899 if (complain & tf_error)
3900 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3902 return error_mark_node;
3906 case UNORDERED_EXPR:
3913 build_type = integer_type_node;
3914 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3916 if (complain & tf_error)
3917 error ("unordered comparison on non-floating point argument");
3918 return error_mark_node;
3927 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
3928 || code0 == ENUMERAL_TYPE)
3929 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3930 || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE)))
3931 arithmetic_types_p = 1;
3934 arithmetic_types_p = 0;
3935 /* Vector arithmetic is only allowed when both sides are vectors. */
3936 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3938 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3939 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3942 binary_op_error (location, code, type0, type1);
3943 return error_mark_node;
3945 arithmetic_types_p = 1;
3948 /* Determine the RESULT_TYPE, if it is not already known. */
3950 && arithmetic_types_p
3951 && (shorten || common || short_compare))
3952 result_type = cp_common_type (type0, type1);
3956 if (complain & tf_error)
3957 error ("invalid operands of types %qT and %qT to binary %qO",
3958 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3959 return error_mark_node;
3962 /* If we're in a template, the only thing we need to know is the
3964 if (processing_template_decl)
3966 /* Since the middle-end checks the type when doing a build2, we
3967 need to build the tree in pieces. This built tree will never
3968 get out of the front-end as we replace it when instantiating
3970 tree tmp = build2 (resultcode,
3971 build_type ? build_type : result_type,
3973 TREE_OPERAND (tmp, 0) = op0;
3977 if (arithmetic_types_p)
3979 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3981 /* For certain operations (which identify themselves by shorten != 0)
3982 if both args were extended from the same smaller type,
3983 do the arithmetic in that type and then extend.
3985 shorten !=0 and !=1 indicates a bitwise operation.
3986 For them, this optimization is safe only if
3987 both args are zero-extended or both are sign-extended.
3988 Otherwise, we might change the result.
3989 E.g., (short)-1 | (unsigned short)-1 is (int)-1
3990 but calculated in (unsigned short) it would be (unsigned short)-1. */
3992 if (shorten && none_complex)
3994 final_type = result_type;
3995 result_type = shorten_binary_op (result_type, op0, op1,
3999 /* Comparison operations are shortened too but differently.
4000 They identify themselves by setting short_compare = 1. */
4004 /* Don't write &op0, etc., because that would prevent op0
4005 from being kept in a register.
4006 Instead, make copies of the our local variables and
4007 pass the copies by reference, then copy them back afterward. */
4008 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
4009 enum tree_code xresultcode = resultcode;
4011 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
4013 return cp_convert (boolean_type_node, val);
4014 op0 = xop0, op1 = xop1;
4016 resultcode = xresultcode;
4019 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
4020 && warn_sign_compare
4021 /* Do not warn until the template is instantiated; we cannot
4022 bound the ranges of the arguments until that point. */
4023 && !processing_template_decl
4024 && (complain & tf_warning)
4025 && c_inhibit_evaluation_warnings == 0)
4027 warn_for_sign_compare (location, orig_op0, orig_op1, op0, op1,
4028 result_type, resultcode);
4032 /* Issue warnings about peculiar, but valid, uses of NULL. */
4033 if ((orig_op0 == null_node || orig_op1 == null_node)
4034 /* It's reasonable to use pointer values as operands of &&
4035 and ||, so NULL is no exception. */
4036 && code != TRUTH_ANDIF_EXPR && code != TRUTH_ORIF_EXPR
4037 && ( /* Both are NULL (or 0) and the operation was not a comparison. */
4038 (null_ptr_cst_p (orig_op0) && null_ptr_cst_p (orig_op1)
4039 && code != EQ_EXPR && code != NE_EXPR)
4040 /* Or if one of OP0 or OP1 is neither a pointer nor NULL. */
4041 || (!null_ptr_cst_p (orig_op0) && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
4042 || (!null_ptr_cst_p (orig_op1) && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE))
4043 && (complain & tf_warning))
4044 /* Some sort of arithmetic operation involving NULL was
4045 performed. Note that pointer-difference and pointer-addition
4046 have already been handled above, and so we don't end up here in
4048 warning (OPT_Wpointer_arith, "NULL used in arithmetic");
4051 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
4052 Then the expression will be built.
4053 It will be given type FINAL_TYPE if that is nonzero;
4054 otherwise, it will be given type RESULT_TYPE. */
4057 if (TREE_TYPE (op0) != result_type)
4058 op0 = cp_convert_and_check (result_type, op0);
4059 if (TREE_TYPE (op1) != result_type)
4060 op1 = cp_convert_and_check (result_type, op1);
4062 if (op0 == error_mark_node || op1 == error_mark_node)
4063 return error_mark_node;
4066 if (build_type == NULL_TREE)
4067 build_type = result_type;
4069 result = build2 (resultcode, build_type, op0, op1);
4070 result = fold_if_not_in_template (result);
4071 if (final_type != 0)
4072 result = cp_convert (final_type, result);
4074 if (TREE_OVERFLOW_P (result)
4075 && !TREE_OVERFLOW_P (op0)
4076 && !TREE_OVERFLOW_P (op1))
4077 overflow_warning (location, result);
4082 /* Return a tree for the sum or difference (RESULTCODE says which)
4083 of pointer PTROP and integer INTOP. */
4086 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
4088 tree res_type = TREE_TYPE (ptrop);
4090 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
4091 in certain circumstance (when it's valid to do so). So we need
4092 to make sure it's complete. We don't need to check here, if we
4093 can actually complete it at all, as those checks will be done in
4094 pointer_int_sum() anyway. */
4095 complete_type (TREE_TYPE (res_type));
4097 return pointer_int_sum (resultcode, ptrop,
4098 fold_if_not_in_template (intop));
4101 /* Return a tree for the difference of pointers OP0 and OP1.
4102 The resulting tree has type int. */
4105 pointer_diff (tree op0, tree op1, tree ptrtype)
4108 tree restype = ptrdiff_type_node;
4109 tree target_type = TREE_TYPE (ptrtype);
4111 if (!complete_type_or_else (target_type, NULL_TREE))
4112 return error_mark_node;
4114 if (TREE_CODE (target_type) == VOID_TYPE)
4115 permerror (input_location, "ISO C++ forbids using pointer of type %<void *%> in subtraction");
4116 if (TREE_CODE (target_type) == FUNCTION_TYPE)
4117 permerror (input_location, "ISO C++ forbids using pointer to a function in subtraction");
4118 if (TREE_CODE (target_type) == METHOD_TYPE)
4119 permerror (input_location, "ISO C++ forbids using pointer to a method in subtraction");
4121 /* First do the subtraction as integers;
4122 then drop through to build the divide operator. */
4124 op0 = cp_build_binary_op (input_location,
4126 cp_convert (restype, op0),
4127 cp_convert (restype, op1),
4128 tf_warning_or_error);
4130 /* This generates an error if op1 is a pointer to an incomplete type. */
4131 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
4132 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
4134 op1 = (TYPE_PTROB_P (ptrtype)
4135 ? size_in_bytes (target_type)
4136 : integer_one_node);
4138 /* Do the division. */
4140 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
4141 return fold_if_not_in_template (result);
4144 /* Construct and perhaps optimize a tree representation
4145 for a unary operation. CODE, a tree_code, specifies the operation
4146 and XARG is the operand. */
4149 build_x_unary_op (enum tree_code code, tree xarg, tsubst_flags_t complain)
4151 tree orig_expr = xarg;
4155 if (processing_template_decl)
4157 if (type_dependent_expression_p (xarg))
4158 return build_min_nt (code, xarg, NULL_TREE);
4160 xarg = build_non_dependent_expr (xarg);
4165 /* [expr.unary.op] says:
4167 The address of an object of incomplete type can be taken.
4169 (And is just the ordinary address operator, not an overloaded
4170 "operator &".) However, if the type is a template
4171 specialization, we must complete the type at this point so that
4172 an overloaded "operator &" will be available if required. */
4173 if (code == ADDR_EXPR
4174 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
4175 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
4176 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
4177 || (TREE_CODE (xarg) == OFFSET_REF)))
4178 /* Don't look for a function. */;
4180 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
4181 /*overloaded_p=*/NULL, complain);
4182 if (!exp && code == ADDR_EXPR)
4184 if (is_overloaded_fn (xarg))
4186 tree fn = get_first_fn (xarg);
4187 if (DECL_CONSTRUCTOR_P (fn) || DECL_DESTRUCTOR_P (fn))
4190 (DECL_CONSTRUCTOR_P (fn) ? "constructor" : "destructor");
4191 error ("taking address of %s %qE", type, xarg);
4192 return error_mark_node;
4196 /* A pointer to member-function can be formed only by saying
4198 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
4199 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
4201 if (TREE_CODE (xarg) != OFFSET_REF
4202 || !TYPE_P (TREE_OPERAND (xarg, 0)))
4204 error ("invalid use of %qE to form a pointer-to-member-function",
4206 if (TREE_CODE (xarg) != OFFSET_REF)
4207 inform (input_location, " a qualified-id is required");
4208 return error_mark_node;
4212 error ("parentheses around %qE cannot be used to form a"
4213 " pointer-to-member-function",
4215 PTRMEM_OK_P (xarg) = 1;
4219 if (TREE_CODE (xarg) == OFFSET_REF)
4221 ptrmem = PTRMEM_OK_P (xarg);
4223 if (!ptrmem && !flag_ms_extensions
4224 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
4226 /* A single non-static member, make sure we don't allow a
4227 pointer-to-member. */
4228 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
4229 TREE_OPERAND (xarg, 0),
4230 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
4231 PTRMEM_OK_P (xarg) = ptrmem;
4234 else if (TREE_CODE (xarg) == TARGET_EXPR && (complain & tf_warning))
4235 warning (0, "taking address of temporary");
4236 exp = cp_build_unary_op (ADDR_EXPR, xarg, 0, complain);
4239 if (processing_template_decl && exp != error_mark_node)
4240 exp = build_min_non_dep (code, exp, orig_expr,
4241 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
4242 if (TREE_CODE (exp) == ADDR_EXPR)
4243 PTRMEM_OK_P (exp) = ptrmem;
4247 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
4248 constants, where a null value is represented by an INTEGER_CST of
4252 cp_truthvalue_conversion (tree expr)
4254 tree type = TREE_TYPE (expr);
4255 if (TYPE_PTRMEM_P (type))
4256 return build_binary_op (EXPR_LOCATION (expr),
4257 NE_EXPR, expr, integer_zero_node, 1);
4259 return c_common_truthvalue_conversion (input_location, expr);
4262 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
4265 condition_conversion (tree expr)
4268 if (processing_template_decl)
4270 t = perform_implicit_conversion (boolean_type_node, expr,
4271 tf_warning_or_error);
4272 t = fold_build_cleanup_point_expr (boolean_type_node, t);
4276 /* Return an ADDR_EXPR giving the address of T. This function
4277 attempts no optimizations or simplifications; it is a low-level
4281 build_address (tree t)
4285 if (error_operand_p (t) || !cxx_mark_addressable (t))
4286 return error_mark_node;
4288 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
4293 /* Return a NOP_EXPR converting EXPR to TYPE. */
4296 build_nop (tree type, tree expr)
4298 if (type == error_mark_node || error_operand_p (expr))
4300 return build1 (NOP_EXPR, type, expr);
4303 /* C++: Must handle pointers to members.
4305 Perhaps type instantiation should be extended to handle conversion
4306 from aggregates to types we don't yet know we want? (Or are those
4307 cases typically errors which should be reported?)
4309 NOCONVERT nonzero suppresses the default promotions
4310 (such as from short to int). */
4313 cp_build_unary_op (enum tree_code code, tree xarg, int noconvert,
4314 tsubst_flags_t complain)
4316 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
4319 const char *errstring = NULL;
4321 const char *invalid_op_diag;
4323 if (error_operand_p (arg))
4324 return error_mark_node;
4326 if ((invalid_op_diag
4327 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
4332 error (invalid_op_diag);
4333 return error_mark_node;
4338 case UNARY_PLUS_EXPR:
4341 int flags = WANT_ARITH | WANT_ENUM;
4342 /* Unary plus (but not unary minus) is allowed on pointers. */
4343 if (code == UNARY_PLUS_EXPR)
4344 flags |= WANT_POINTER;
4345 arg = build_expr_type_conversion (flags, arg, true);
4347 errstring = (code == NEGATE_EXPR
4348 ? "wrong type argument to unary minus"
4349 : "wrong type argument to unary plus");
4352 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4353 arg = perform_integral_promotions (arg);
4355 /* Make sure the result is not an lvalue: a unary plus or minus
4356 expression is always a rvalue. */
4363 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4367 arg = default_conversion (arg);
4369 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM
4372 errstring = "wrong type argument to bit-complement";
4373 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4374 arg = perform_integral_promotions (arg);
4378 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4379 errstring = "wrong type argument to abs";
4380 else if (!noconvert)
4381 arg = default_conversion (arg);
4385 /* Conjugating a real value is a no-op, but allow it anyway. */
4386 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4387 errstring = "wrong type argument to conjugation";
4388 else if (!noconvert)
4389 arg = default_conversion (arg);
4392 case TRUTH_NOT_EXPR:
4393 arg = perform_implicit_conversion (boolean_type_node, arg,
4395 val = invert_truthvalue (arg);
4396 if (arg != error_mark_node)
4398 errstring = "in argument to unary !";
4405 if (TREE_CODE (arg) == COMPLEX_CST)
4406 return TREE_REALPART (arg);
4407 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4409 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4410 return fold_if_not_in_template (arg);
4416 if (TREE_CODE (arg) == COMPLEX_CST)
4417 return TREE_IMAGPART (arg);
4418 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4420 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4421 return fold_if_not_in_template (arg);
4424 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4426 case PREINCREMENT_EXPR:
4427 case POSTINCREMENT_EXPR:
4428 case PREDECREMENT_EXPR:
4429 case POSTDECREMENT_EXPR:
4430 /* Handle complex lvalues (when permitted)
4431 by reduction to simpler cases. */
4433 val = unary_complex_lvalue (code, arg);
4437 /* Increment or decrement the real part of the value,
4438 and don't change the imaginary part. */
4439 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4443 arg = stabilize_reference (arg);
4444 real = cp_build_unary_op (REALPART_EXPR, arg, 1, complain);
4445 imag = cp_build_unary_op (IMAGPART_EXPR, arg, 1, complain);
4446 real = cp_build_unary_op (code, real, 1, complain);
4447 if (real == error_mark_node || imag == error_mark_node)
4448 return error_mark_node;
4449 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4453 /* Report invalid types. */
4455 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4458 if (code == PREINCREMENT_EXPR)
4459 errstring ="no pre-increment operator for type";
4460 else if (code == POSTINCREMENT_EXPR)
4461 errstring ="no post-increment operator for type";
4462 else if (code == PREDECREMENT_EXPR)
4463 errstring ="no pre-decrement operator for type";
4465 errstring ="no post-decrement operator for type";
4468 else if (arg == error_mark_node)
4469 return error_mark_node;
4471 /* Report something read-only. */
4473 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4474 || TREE_READONLY (arg))
4476 if (complain & tf_error)
4477 readonly_error (arg, ((code == PREINCREMENT_EXPR
4478 || code == POSTINCREMENT_EXPR)
4479 ? "increment" : "decrement"));
4481 return error_mark_node;
4486 tree declared_type = unlowered_expr_type (arg);
4488 argtype = TREE_TYPE (arg);
4490 /* ARM $5.2.5 last annotation says this should be forbidden. */
4491 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4493 if (complain & tf_error)
4494 permerror (input_location, (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4495 ? G_("ISO C++ forbids incrementing an enum")
4496 : G_("ISO C++ forbids decrementing an enum"));
4498 return error_mark_node;
4501 /* Compute the increment. */
4503 if (TREE_CODE (argtype) == POINTER_TYPE)
4505 tree type = complete_type (TREE_TYPE (argtype));
4507 if (!COMPLETE_OR_VOID_TYPE_P (type))
4509 if (complain & tf_error)
4510 error (((code == PREINCREMENT_EXPR
4511 || code == POSTINCREMENT_EXPR))
4512 ? G_("cannot increment a pointer to incomplete type %qT")
4513 : G_("cannot decrement a pointer to incomplete type %qT"),
4514 TREE_TYPE (argtype));
4516 return error_mark_node;
4518 else if ((pedantic || warn_pointer_arith)
4519 && !TYPE_PTROB_P (argtype))
4521 if (complain & tf_error)
4522 permerror (input_location, (code == PREINCREMENT_EXPR
4523 || code == POSTINCREMENT_EXPR)
4524 ? G_("ISO C++ forbids incrementing a pointer of type %qT")
4525 : G_("ISO C++ forbids decrementing a pointer of type %qT"),
4528 return error_mark_node;
4531 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4534 inc = integer_one_node;
4536 inc = cp_convert (argtype, inc);
4538 /* Complain about anything else that is not a true lvalue. */
4539 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4540 || code == POSTINCREMENT_EXPR)
4541 ? lv_increment : lv_decrement),
4543 return error_mark_node;
4545 /* Forbid using -- on `bool'. */
4546 if (same_type_p (declared_type, boolean_type_node))
4548 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4550 if (complain & tf_error)
4551 error ("invalid use of Boolean expression as operand "
4552 "to %<operator--%>");
4553 return error_mark_node;
4555 val = boolean_increment (code, arg);
4558 val = build2 (code, TREE_TYPE (arg), arg, inc);
4560 TREE_SIDE_EFFECTS (val) = 1;
4565 /* Note that this operation never does default_conversion
4566 regardless of NOCONVERT. */
4568 argtype = lvalue_type (arg);
4570 if (TREE_CODE (arg) == OFFSET_REF)
4573 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4575 tree type = build_pointer_type (TREE_TYPE (argtype));
4576 arg = build1 (CONVERT_EXPR, type, arg);
4579 else if (pedantic && DECL_MAIN_P (arg))
4582 /* Apparently a lot of autoconf scripts for C++ packages do this,
4583 so only complain if -pedantic. */
4584 if (complain & (flag_pedantic_errors ? tf_error : tf_warning))
4585 pedwarn (input_location, OPT_pedantic,
4586 "ISO C++ forbids taking address of function %<::main%>");
4587 else if (flag_pedantic_errors)
4588 return error_mark_node;
4591 /* Let &* cancel out to simplify resulting code. */
4592 if (TREE_CODE (arg) == INDIRECT_REF)
4594 /* We don't need to have `current_class_ptr' wrapped in a
4595 NON_LVALUE_EXPR node. */
4596 if (arg == current_class_ref)
4597 return current_class_ptr;
4599 arg = TREE_OPERAND (arg, 0);
4600 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4602 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4603 arg = build1 (CONVERT_EXPR, type, arg);
4606 /* Don't let this be an lvalue. */
4611 /* Uninstantiated types are all functions. Taking the
4612 address of a function is a no-op, so just return the
4615 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4616 || !IDENTIFIER_OPNAME_P (arg));
4618 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4619 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4621 /* They're trying to take the address of a unique non-static
4622 member function. This is ill-formed (except in MS-land),
4623 but let's try to DTRT.
4624 Note: We only handle unique functions here because we don't
4625 want to complain if there's a static overload; non-unique
4626 cases will be handled by instantiate_type. But we need to
4627 handle this case here to allow casts on the resulting PMF.
4628 We could defer this in non-MS mode, but it's easier to give
4629 a useful error here. */
4631 /* Inside constant member functions, the `this' pointer
4632 contains an extra const qualifier. TYPE_MAIN_VARIANT
4633 is used here to remove this const from the diagnostics
4634 and the created OFFSET_REF. */
4635 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4636 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4639 if (! flag_ms_extensions)
4641 tree name = DECL_NAME (fn);
4642 if (!(complain & tf_error))
4643 return error_mark_node;
4644 else if (current_class_type
4645 && TREE_OPERAND (arg, 0) == current_class_ref)
4646 /* An expression like &memfn. */
4647 permerror (input_location, "ISO C++ forbids taking the address of an unqualified"
4648 " or parenthesized non-static member function to form"
4649 " a pointer to member function. Say %<&%T::%D%>",
4652 permerror (input_location, "ISO C++ forbids taking the address of a bound member"
4653 " function to form a pointer to member function."
4657 arg = build_offset_ref (base, fn, /*address_p=*/true);
4661 if (type_unknown_p (arg))
4662 return build1 (ADDR_EXPR, unknown_type_node, arg);
4664 /* Handle complex lvalues (when permitted)
4665 by reduction to simpler cases. */
4666 val = unary_complex_lvalue (code, arg);
4670 switch (TREE_CODE (arg))
4674 case FIX_TRUNC_EXPR:
4675 /* Even if we're not being pedantic, we cannot allow this
4676 extension when we're instantiating in a SFINAE
4678 if (! lvalue_p (arg) && complain == tf_none)
4680 if (complain & tf_error)
4681 permerror (input_location, "ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4683 return error_mark_node;
4688 arg = BASELINK_FUNCTIONS (arg);
4692 arg = OVL_CURRENT (arg);
4696 /* Turn a reference to a non-static data member into a
4697 pointer-to-member. */
4702 if (!PTRMEM_OK_P (arg))
4703 return cp_build_unary_op (code, arg, 0, complain);
4705 t = TREE_OPERAND (arg, 1);
4706 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4708 if (complain & tf_error)
4709 error ("cannot create pointer to reference member %qD", t);
4710 return error_mark_node;
4713 type = build_ptrmem_type (context_for_name_lookup (t),
4715 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4723 /* Anything not already handled and not a true memory reference
4725 if (TREE_CODE (argtype) != FUNCTION_TYPE
4726 && TREE_CODE (argtype) != METHOD_TYPE
4727 && TREE_CODE (arg) != OFFSET_REF
4728 && !lvalue_or_else (arg, lv_addressof, complain))
4729 return error_mark_node;
4731 if (argtype != error_mark_node)
4732 argtype = build_pointer_type (argtype);
4734 /* In a template, we are processing a non-dependent expression
4735 so we can just form an ADDR_EXPR with the correct type. */
4736 if (processing_template_decl || TREE_CODE (arg) != COMPONENT_REF)
4738 val = build_address (arg);
4739 if (TREE_CODE (arg) == OFFSET_REF)
4740 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4742 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4744 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4746 /* We can only get here with a single static member
4748 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4749 && DECL_STATIC_FUNCTION_P (fn));
4751 val = build_address (fn);
4752 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4753 /* Do not lose object's side effects. */
4754 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4755 TREE_OPERAND (arg, 0), val);
4757 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4759 if (complain & tf_error)
4760 error ("attempt to take address of bit-field structure member %qD",
4761 TREE_OPERAND (arg, 1));
4762 return error_mark_node;
4766 tree object = TREE_OPERAND (arg, 0);
4767 tree field = TREE_OPERAND (arg, 1);
4768 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4769 (TREE_TYPE (object), decl_type_context (field)));
4770 val = build_address (arg);
4773 if (TREE_CODE (argtype) == POINTER_TYPE
4774 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4776 build_ptrmemfunc_type (argtype);
4777 val = build_ptrmemfunc (argtype, val, 0,
4778 /*c_cast_p=*/false);
4790 argtype = TREE_TYPE (arg);
4791 return fold_if_not_in_template (build1 (code, argtype, arg));
4794 if (complain & tf_error)
4795 error ("%s", errstring);
4796 return error_mark_node;
4799 /* Hook for the c-common bits that build a unary op. */
4801 build_unary_op (location_t location ATTRIBUTE_UNUSED,
4802 enum tree_code code, tree xarg, int noconvert)
4804 return cp_build_unary_op (code, xarg, noconvert, tf_warning_or_error);
4807 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4808 for certain kinds of expressions which are not really lvalues
4809 but which we can accept as lvalues.
4811 If ARG is not a kind of expression we can handle, return
4815 unary_complex_lvalue (enum tree_code code, tree arg)
4817 /* Inside a template, making these kinds of adjustments is
4818 pointless; we are only concerned with the type of the
4820 if (processing_template_decl)
4823 /* Handle (a, b) used as an "lvalue". */
4824 if (TREE_CODE (arg) == COMPOUND_EXPR)
4826 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 1), 0,
4827 tf_warning_or_error);
4828 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4829 TREE_OPERAND (arg, 0), real_result);
4832 /* Handle (a ? b : c) used as an "lvalue". */
4833 if (TREE_CODE (arg) == COND_EXPR
4834 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4835 return rationalize_conditional_expr (code, arg, tf_warning_or_error);
4837 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4838 if (TREE_CODE (arg) == MODIFY_EXPR
4839 || TREE_CODE (arg) == PREINCREMENT_EXPR
4840 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4842 tree lvalue = TREE_OPERAND (arg, 0);
4843 if (TREE_SIDE_EFFECTS (lvalue))
4845 lvalue = stabilize_reference (lvalue);
4846 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4847 lvalue, TREE_OPERAND (arg, 1));
4849 return unary_complex_lvalue
4850 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4853 if (code != ADDR_EXPR)
4856 /* Handle (a = b) used as an "lvalue" for `&'. */
4857 if (TREE_CODE (arg) == MODIFY_EXPR
4858 || TREE_CODE (arg) == INIT_EXPR)
4860 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 0), 0,
4861 tf_warning_or_error);
4862 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4864 TREE_NO_WARNING (arg) = 1;
4868 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4869 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4870 || TREE_CODE (arg) == OFFSET_REF)
4873 /* We permit compiler to make function calls returning
4874 objects of aggregate type look like lvalues. */
4878 if (TREE_CODE (targ) == SAVE_EXPR)
4879 targ = TREE_OPERAND (targ, 0);
4881 if (TREE_CODE (targ) == CALL_EXPR && MAYBE_CLASS_TYPE_P (TREE_TYPE (targ)))
4883 if (TREE_CODE (arg) == SAVE_EXPR)
4886 targ = build_cplus_new (TREE_TYPE (arg), arg);
4887 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4890 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4891 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4892 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4895 /* Don't let anything else be handled specially. */
4899 /* Mark EXP saying that we need to be able to take the
4900 address of it; it should not be allocated in a register.
4901 Value is true if successful.
4903 C++: we do not allow `current_class_ptr' to be addressable. */
4906 cxx_mark_addressable (tree exp)
4911 switch (TREE_CODE (x))
4918 x = TREE_OPERAND (x, 0);
4922 if (x == current_class_ptr)
4924 error ("cannot take the address of %<this%>, which is an rvalue expression");
4925 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4931 /* Caller should not be trying to mark initialized
4932 constant fields addressable. */
4933 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4934 || DECL_IN_AGGR_P (x) == 0
4936 || DECL_EXTERNAL (x));
4941 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4942 && !DECL_ARTIFICIAL (x))
4944 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4947 ("address of explicit register variable %qD requested", x);
4950 else if (extra_warnings)
4952 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
4954 TREE_ADDRESSABLE (x) = 1;
4958 TREE_ADDRESSABLE (x) = 1;
4962 TREE_ADDRESSABLE (x) = 1;
4966 TREE_ADDRESSABLE (x) = 1;
4967 cxx_mark_addressable (TREE_OPERAND (x, 0));
4975 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4978 build_x_conditional_expr (tree ifexp, tree op1, tree op2,
4979 tsubst_flags_t complain)
4981 tree orig_ifexp = ifexp;
4982 tree orig_op1 = op1;
4983 tree orig_op2 = op2;
4986 if (processing_template_decl)
4988 /* The standard says that the expression is type-dependent if
4989 IFEXP is type-dependent, even though the eventual type of the
4990 expression doesn't dependent on IFEXP. */
4991 if (type_dependent_expression_p (ifexp)
4992 /* As a GNU extension, the middle operand may be omitted. */
4993 || (op1 && type_dependent_expression_p (op1))
4994 || type_dependent_expression_p (op2))
4995 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4996 ifexp = build_non_dependent_expr (ifexp);
4998 op1 = build_non_dependent_expr (op1);
4999 op2 = build_non_dependent_expr (op2);
5002 expr = build_conditional_expr (ifexp, op1, op2, complain);
5003 if (processing_template_decl && expr != error_mark_node)
5004 return build_min_non_dep (COND_EXPR, expr,
5005 orig_ifexp, orig_op1, orig_op2);
5009 /* Given a list of expressions, return a compound expression
5010 that performs them all and returns the value of the last of them. */
5012 tree build_x_compound_expr_from_list (tree list, const char *msg)
5014 tree expr = TREE_VALUE (list);
5016 if (TREE_CHAIN (list))
5019 permerror (input_location, "%s expression list treated as compound expression", msg);
5021 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
5022 expr = build_x_compound_expr (expr, TREE_VALUE (list),
5023 tf_warning_or_error);
5029 /* Like build_x_compound_expr_from_list, but using a VEC. */
5032 build_x_compound_expr_from_vec (VEC(tree,gc) *vec, const char *msg)
5034 if (VEC_empty (tree, vec))
5036 else if (VEC_length (tree, vec) == 1)
5037 return VEC_index (tree, vec, 0);
5045 permerror (input_location,
5046 "%s expression list treated as compound expression",
5049 expr = VEC_index (tree, vec, 0);
5050 for (ix = 1; VEC_iterate (tree, vec, ix, t); ++ix)
5051 expr = build_x_compound_expr (expr, t, tf_warning_or_error);
5057 /* Handle overloading of the ',' operator when needed. */
5060 build_x_compound_expr (tree op1, tree op2, tsubst_flags_t complain)
5063 tree orig_op1 = op1;
5064 tree orig_op2 = op2;
5066 if (processing_template_decl)
5068 if (type_dependent_expression_p (op1)
5069 || type_dependent_expression_p (op2))
5070 return build_min_nt (COMPOUND_EXPR, op1, op2);
5071 op1 = build_non_dependent_expr (op1);
5072 op2 = build_non_dependent_expr (op2);
5075 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
5076 /*overloaded_p=*/NULL, complain);
5078 result = cp_build_compound_expr (op1, op2, complain);
5080 if (processing_template_decl && result != error_mark_node)
5081 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
5086 /* Like cp_build_compound_expr, but for the c-common bits. */
5089 build_compound_expr (location_t loc ATTRIBUTE_UNUSED, tree lhs, tree rhs)
5091 return cp_build_compound_expr (lhs, rhs, tf_warning_or_error);
5094 /* Build a compound expression. */
5097 cp_build_compound_expr (tree lhs, tree rhs, tsubst_flags_t complain)
5099 lhs = convert_to_void (lhs, "left-hand operand of comma", complain);
5101 if (lhs == error_mark_node || rhs == error_mark_node)
5102 return error_mark_node;
5104 if (TREE_CODE (rhs) == TARGET_EXPR)
5106 /* If the rhs is a TARGET_EXPR, then build the compound
5107 expression inside the target_expr's initializer. This
5108 helps the compiler to eliminate unnecessary temporaries. */
5109 tree init = TREE_OPERAND (rhs, 1);
5111 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
5112 TREE_OPERAND (rhs, 1) = init;
5117 if (type_unknown_p (rhs))
5119 error ("no context to resolve type of %qE", rhs);
5120 return error_mark_node;
5123 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
5126 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
5127 casts away constness. CAST gives the type of cast.
5129 ??? This function warns for casting away any qualifier not just
5130 const. We would like to specify exactly what qualifiers are casted
5135 check_for_casting_away_constness (tree src_type, tree dest_type,
5136 enum tree_code cast)
5138 /* C-style casts are allowed to cast away constness. With
5139 WARN_CAST_QUAL, we still want to issue a warning. */
5140 if (cast == CAST_EXPR && !warn_cast_qual)
5143 if (!casts_away_constness (src_type, dest_type))
5149 warning (OPT_Wcast_qual,
5150 "cast from type %qT to type %qT casts away qualifiers",
5151 src_type, dest_type);
5154 case STATIC_CAST_EXPR:
5155 error ("static_cast from type %qT to type %qT casts away qualifiers",
5156 src_type, dest_type);
5159 case REINTERPRET_CAST_EXPR:
5160 error ("reinterpret_cast from type %qT to type %qT casts away qualifiers",
5161 src_type, dest_type);
5168 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
5169 (another pointer-to-member type in the same hierarchy) and return
5170 the converted expression. If ALLOW_INVERSE_P is permitted, a
5171 pointer-to-derived may be converted to pointer-to-base; otherwise,
5172 only the other direction is permitted. If C_CAST_P is true, this
5173 conversion is taking place as part of a C-style cast. */
5176 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
5179 if (TYPE_PTRMEM_P (type))
5183 if (TREE_CODE (expr) == PTRMEM_CST)
5184 expr = cplus_expand_constant (expr);
5185 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
5186 TYPE_PTRMEM_CLASS_TYPE (type),
5189 if (!integer_zerop (delta))
5191 tree cond, op1, op2;
5193 cond = cp_build_binary_op (input_location,
5196 build_int_cst (TREE_TYPE (expr), -1),
5197 tf_warning_or_error);
5198 op1 = build_nop (ptrdiff_type_node, expr);
5199 op2 = cp_build_binary_op (input_location,
5200 PLUS_EXPR, op1, delta,
5201 tf_warning_or_error);
5203 expr = fold_build3 (COND_EXPR, ptrdiff_type_node, cond, op1, op2);
5207 return build_nop (type, expr);
5210 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
5211 allow_inverse_p, c_cast_p);
5214 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
5215 a version of EXPR that has TREE_OVERFLOW set if it is set in ORIG.
5216 Otherwise, return EXPR unchanged. */
5219 ignore_overflows (tree expr, tree orig)
5221 if (TREE_CODE (expr) == INTEGER_CST
5222 && CONSTANT_CLASS_P (orig)
5223 && TREE_CODE (orig) != STRING_CST
5224 && TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig))
5226 if (!TREE_OVERFLOW (orig))
5227 /* Ensure constant sharing. */
5228 expr = build_int_cst_wide (TREE_TYPE (expr),
5229 TREE_INT_CST_LOW (expr),
5230 TREE_INT_CST_HIGH (expr));
5233 /* Avoid clobbering a shared constant. */
5234 expr = copy_node (expr);
5235 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
5241 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
5242 this static_cast is being attempted as one of the possible casts
5243 allowed by a C-style cast. (In that case, accessibility of base
5244 classes is not considered, and it is OK to cast away
5245 constness.) Return the result of the cast. *VALID_P is set to
5246 indicate whether or not the cast was valid. */
5249 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
5250 bool *valid_p, tsubst_flags_t complain)
5256 /* Assume the cast is valid. */
5259 intype = TREE_TYPE (expr);
5261 /* Save casted types in the function's used types hash table. */
5262 used_types_insert (type);
5264 /* [expr.static.cast]
5266 An lvalue of type "cv1 B", where B is a class type, can be cast
5267 to type "reference to cv2 D", where D is a class derived (clause
5268 _class.derived_) from B, if a valid standard conversion from
5269 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
5270 same cv-qualification as, or greater cv-qualification than, cv1,
5271 and B is not a virtual base class of D. */
5272 /* We check this case before checking the validity of "TYPE t =
5273 EXPR;" below because for this case:
5276 struct D : public B { D(const B&); };
5278 void f() { static_cast<const D&>(b); }
5280 we want to avoid constructing a new D. The standard is not
5281 completely clear about this issue, but our interpretation is
5282 consistent with other compilers. */
5283 if (TREE_CODE (type) == REFERENCE_TYPE
5284 && CLASS_TYPE_P (TREE_TYPE (type))
5285 && CLASS_TYPE_P (intype)
5286 && real_lvalue_p (expr)
5287 && DERIVED_FROM_P (intype, TREE_TYPE (type))
5288 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
5289 build_pointer_type (TYPE_MAIN_VARIANT
5290 (TREE_TYPE (type))))
5292 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5296 /* There is a standard conversion from "D*" to "B*" even if "B"
5297 is ambiguous or inaccessible. If this is really a
5298 static_cast, then we check both for inaccessibility and
5299 ambiguity. However, if this is a static_cast being performed
5300 because the user wrote a C-style cast, then accessibility is
5302 base = lookup_base (TREE_TYPE (type), intype,
5303 c_cast_p ? ba_unique : ba_check,
5306 /* Convert from "B*" to "D*". This function will check that "B"
5307 is not a virtual base of "D". */
5308 expr = build_base_path (MINUS_EXPR, build_address (expr),
5309 base, /*nonnull=*/false);
5310 /* Convert the pointer to a reference -- but then remember that
5311 there are no expressions with reference type in C++. */
5312 return convert_from_reference (build_nop (type, expr));
5317 /* [expr.static.cast]
5319 An expression e can be explicitly converted to a type T using a
5320 static_cast of the form static_cast<T>(e) if the declaration T
5321 t(e);" is well-formed, for some invented temporary variable
5323 result = perform_direct_initialization_if_possible (type, expr,
5324 c_cast_p, complain);
5327 result = convert_from_reference (result);
5329 /* Ignore any integer overflow caused by the cast. */
5330 result = ignore_overflows (result, orig);
5332 /* [expr.static.cast]
5334 If T is a reference type, the result is an lvalue; otherwise,
5335 the result is an rvalue. */
5336 if (TREE_CODE (type) != REFERENCE_TYPE)
5337 result = rvalue (result);
5341 /* [expr.static.cast]
5343 Any expression can be explicitly converted to type cv void. */
5344 if (TREE_CODE (type) == VOID_TYPE)
5345 return convert_to_void (expr, /*implicit=*/NULL, complain);
5347 /* [expr.static.cast]
5349 The inverse of any standard conversion sequence (clause _conv_),
5350 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
5351 (_conv.array_), function-to-pointer (_conv.func_), and boolean
5352 (_conv.bool_) conversions, can be performed explicitly using
5353 static_cast subject to the restriction that the explicit
5354 conversion does not cast away constness (_expr.const.cast_), and
5355 the following additional rules for specific cases: */
5356 /* For reference, the conversions not excluded are: integral
5357 promotions, floating point promotion, integral conversions,
5358 floating point conversions, floating-integral conversions,
5359 pointer conversions, and pointer to member conversions. */
5362 A value of integral _or enumeration_ type can be explicitly
5363 converted to an enumeration type. */
5364 /* The effect of all that is that any conversion between any two
5365 types which are integral, floating, or enumeration types can be
5367 if ((INTEGRAL_OR_ENUMERATION_TYPE_P (type)
5368 || SCALAR_FLOAT_TYPE_P (type))
5369 && (INTEGRAL_OR_ENUMERATION_TYPE_P (intype)
5370 || SCALAR_FLOAT_TYPE_P (intype)))
5372 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
5374 /* Ignore any integer overflow caused by the cast. */
5375 expr = ignore_overflows (expr, orig);
5379 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
5380 && CLASS_TYPE_P (TREE_TYPE (type))
5381 && CLASS_TYPE_P (TREE_TYPE (intype))
5382 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
5383 (TREE_TYPE (intype))),
5384 build_pointer_type (TYPE_MAIN_VARIANT
5385 (TREE_TYPE (type)))))
5390 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5391 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
5392 c_cast_p ? ba_unique : ba_check,
5394 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
5397 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5398 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5405 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
5406 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
5408 if (TYPE_PTRMEM_P (type))
5410 t1 = (build_ptrmem_type
5412 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
5413 t2 = (build_ptrmem_type
5415 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
5422 if (can_convert (t1, t2) || can_convert (t2, t1))
5425 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5426 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
5431 /* [expr.static.cast]
5433 An rvalue of type "pointer to cv void" can be explicitly
5434 converted to a pointer to object type. A value of type pointer
5435 to object converted to "pointer to cv void" and back to the
5436 original pointer type will have its original value. */
5437 if (TREE_CODE (intype) == POINTER_TYPE
5438 && VOID_TYPE_P (TREE_TYPE (intype))
5439 && TYPE_PTROB_P (type))
5442 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5443 return build_nop (type, expr);
5447 return error_mark_node;
5450 /* Return an expression representing static_cast<TYPE>(EXPR). */
5453 build_static_cast (tree type, tree expr, tsubst_flags_t complain)
5458 if (type == error_mark_node || expr == error_mark_node)
5459 return error_mark_node;
5461 if (processing_template_decl)
5463 expr = build_min (STATIC_CAST_EXPR, type, expr);
5464 /* We don't know if it will or will not have side effects. */
5465 TREE_SIDE_EFFECTS (expr) = 1;
5466 return convert_from_reference (expr);
5469 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5470 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5471 if (TREE_CODE (type) != REFERENCE_TYPE
5472 && TREE_CODE (expr) == NOP_EXPR
5473 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5474 expr = TREE_OPERAND (expr, 0);
5476 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p,
5481 if (complain & tf_error)
5482 error ("invalid static_cast from type %qT to type %qT",
5483 TREE_TYPE (expr), type);
5484 return error_mark_node;
5487 /* EXPR is an expression with member function or pointer-to-member
5488 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5489 not permitted by ISO C++, but we accept it in some modes. If we
5490 are not in one of those modes, issue a diagnostic. Return the
5491 converted expression. */
5494 convert_member_func_to_ptr (tree type, tree expr)
5499 intype = TREE_TYPE (expr);
5500 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
5501 || TREE_CODE (intype) == METHOD_TYPE);
5503 if (pedantic || warn_pmf2ptr)
5504 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpmf_conversions,
5505 "converting from %qT to %qT", intype, type);
5507 if (TREE_CODE (intype) == METHOD_TYPE)
5508 expr = build_addr_func (expr);
5509 else if (TREE_CODE (expr) == PTRMEM_CST)
5510 expr = build_address (PTRMEM_CST_MEMBER (expr));
5513 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
5514 decl = build_address (decl);
5515 expr = get_member_function_from_ptrfunc (&decl, expr);
5518 return build_nop (type, expr);
5521 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5522 If C_CAST_P is true, this reinterpret cast is being done as part of
5523 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5524 indicate whether or not reinterpret_cast was valid. */
5527 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5528 bool *valid_p, tsubst_flags_t complain)
5532 /* Assume the cast is invalid. */
5536 if (type == error_mark_node || error_operand_p (expr))
5537 return error_mark_node;
5539 intype = TREE_TYPE (expr);
5541 /* Save casted types in the function's used types hash table. */
5542 used_types_insert (type);
5544 /* [expr.reinterpret.cast]
5545 An lvalue expression of type T1 can be cast to the type
5546 "reference to T2" if an expression of type "pointer to T1" can be
5547 explicitly converted to the type "pointer to T2" using a
5548 reinterpret_cast. */
5549 if (TREE_CODE (type) == REFERENCE_TYPE)
5551 if (! real_lvalue_p (expr))
5553 if (complain & tf_error)
5554 error ("invalid cast of an rvalue expression of type "
5557 return error_mark_node;
5560 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5561 "B" are related class types; the reinterpret_cast does not
5562 adjust the pointer. */
5563 if (TYPE_PTR_P (intype)
5564 && (complain & tf_warning)
5565 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5566 COMPARE_BASE | COMPARE_DERIVED)))
5567 warning (0, "casting %qT to %qT does not dereference pointer",
5570 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
5571 if (expr != error_mark_node)
5572 expr = build_reinterpret_cast_1
5573 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5575 if (expr != error_mark_node)
5576 expr = cp_build_indirect_ref (expr, 0, complain);
5580 /* As a G++ extension, we consider conversions from member
5581 functions, and pointers to member functions to
5582 pointer-to-function and pointer-to-void types. If
5583 -Wno-pmf-conversions has not been specified,
5584 convert_member_func_to_ptr will issue an error message. */
5585 if ((TYPE_PTRMEMFUNC_P (intype)
5586 || TREE_CODE (intype) == METHOD_TYPE)
5587 && TYPE_PTR_P (type)
5588 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5589 || VOID_TYPE_P (TREE_TYPE (type))))
5590 return convert_member_func_to_ptr (type, expr);
5592 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5593 array-to-pointer, and function-to-pointer conversions are
5595 expr = decay_conversion (expr);
5597 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5598 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5599 if (TREE_CODE (expr) == NOP_EXPR
5600 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5601 expr = TREE_OPERAND (expr, 0);
5603 if (error_operand_p (expr))
5604 return error_mark_node;
5606 intype = TREE_TYPE (expr);
5608 /* [expr.reinterpret.cast]
5609 A pointer can be converted to any integral type large enough to
5611 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5613 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5615 if (complain & tf_error)
5616 permerror (input_location, "cast from %qT to %qT loses precision",
5619 return error_mark_node;
5622 /* [expr.reinterpret.cast]
5623 A value of integral or enumeration type can be explicitly
5624 converted to a pointer. */
5625 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5628 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5629 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5630 return fold_if_not_in_template (build_nop (type, expr));
5631 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5632 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5637 check_for_casting_away_constness (intype, type, REINTERPRET_CAST_EXPR);
5638 /* Warn about possible alignment problems. */
5639 if (STRICT_ALIGNMENT && warn_cast_align
5640 && (complain & tf_warning)
5641 && !VOID_TYPE_P (type)
5642 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5643 && COMPLETE_TYPE_P (TREE_TYPE (type))
5644 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5645 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5646 warning (OPT_Wcast_align, "cast from %qT to %qT "
5647 "increases required alignment of target type", intype, type);
5649 /* We need to strip nops here, because the front end likes to
5650 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5652 if (warn_strict_aliasing <= 2)
5653 strict_aliasing_warning (intype, type, sexpr);
5655 return fold_if_not_in_template (build_nop (type, expr));
5657 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5658 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5660 if (pedantic && (complain & tf_warning))
5661 /* Only issue a warning, as we have always supported this
5662 where possible, and it is necessary in some cases. DR 195
5663 addresses this issue, but as of 2004/10/26 is still in
5665 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5666 return fold_if_not_in_template (build_nop (type, expr));
5668 else if (TREE_CODE (type) == VECTOR_TYPE)
5669 return fold_if_not_in_template (convert_to_vector (type, expr));
5670 else if (TREE_CODE (intype) == VECTOR_TYPE
5671 && INTEGRAL_OR_ENUMERATION_TYPE_P (type))
5672 return fold_if_not_in_template (convert_to_integer (type, expr));
5677 if (complain & tf_error)
5678 error ("invalid cast from type %qT to type %qT", intype, type);
5679 return error_mark_node;
5682 return cp_convert (type, expr);
5686 build_reinterpret_cast (tree type, tree expr, tsubst_flags_t complain)
5688 if (type == error_mark_node || expr == error_mark_node)
5689 return error_mark_node;
5691 if (processing_template_decl)
5693 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5695 if (!TREE_SIDE_EFFECTS (t)
5696 && type_dependent_expression_p (expr))
5697 /* There might turn out to be side effects inside expr. */
5698 TREE_SIDE_EFFECTS (t) = 1;
5699 return convert_from_reference (t);
5702 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5703 /*valid_p=*/NULL, complain);
5706 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5707 return an appropriate expression. Otherwise, return
5708 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5709 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5710 performing a C-style cast, its value upon return will indicate
5711 whether or not the conversion succeeded. */
5714 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5718 tree reference_type;
5720 /* Callers are responsible for handling error_mark_node as a
5721 destination type. */
5722 gcc_assert (dst_type != error_mark_node);
5723 /* In a template, callers should be building syntactic
5724 representations of casts, not using this machinery. */
5725 gcc_assert (!processing_template_decl);
5727 /* Assume the conversion is invalid. */
5731 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5734 error ("invalid use of const_cast with type %qT, "
5735 "which is not a pointer, "
5736 "reference, nor a pointer-to-data-member type", dst_type);
5737 return error_mark_node;
5740 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5743 error ("invalid use of const_cast with type %qT, which is a pointer "
5744 "or reference to a function type", dst_type);
5745 return error_mark_node;
5748 /* Save casted types in the function's used types hash table. */
5749 used_types_insert (dst_type);
5751 src_type = TREE_TYPE (expr);
5752 /* Expressions do not really have reference types. */
5753 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5754 src_type = TREE_TYPE (src_type);
5756 /* [expr.const.cast]
5758 An lvalue of type T1 can be explicitly converted to an lvalue of
5759 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5760 types) if a pointer to T1 can be explicitly converted to the type
5761 pointer to T2 using a const_cast. */
5762 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5764 reference_type = dst_type;
5765 if (! real_lvalue_p (expr))
5768 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5769 src_type, dst_type);
5770 return error_mark_node;
5772 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5773 src_type = build_pointer_type (src_type);
5777 reference_type = NULL_TREE;
5778 /* If the destination type is not a reference type, the
5779 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5780 conversions are performed. */
5781 src_type = type_decays_to (src_type);
5782 if (src_type == error_mark_node)
5783 return error_mark_node;
5786 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5787 && comp_ptr_ttypes_const (dst_type, src_type))
5792 /* This cast is actually a C-style cast. Issue a warning if
5793 the user is making a potentially unsafe cast. */
5794 check_for_casting_away_constness (src_type, dst_type, CAST_EXPR);
5798 expr = cp_build_unary_op (ADDR_EXPR, expr, 0,
5799 complain? tf_warning_or_error : tf_none);
5800 expr = build_nop (reference_type, expr);
5801 return convert_from_reference (expr);
5805 expr = decay_conversion (expr);
5806 /* build_c_cast puts on a NOP_EXPR to make the result not an
5807 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5808 non-lvalue context. */
5809 if (TREE_CODE (expr) == NOP_EXPR
5810 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5811 expr = TREE_OPERAND (expr, 0);
5812 return build_nop (dst_type, expr);
5817 error ("invalid const_cast from type %qT to type %qT",
5818 src_type, dst_type);
5819 return error_mark_node;
5823 build_const_cast (tree type, tree expr, tsubst_flags_t complain)
5825 if (type == error_mark_node || error_operand_p (expr))
5826 return error_mark_node;
5828 if (processing_template_decl)
5830 tree t = build_min (CONST_CAST_EXPR, type, expr);
5832 if (!TREE_SIDE_EFFECTS (t)
5833 && type_dependent_expression_p (expr))
5834 /* There might turn out to be side effects inside expr. */
5835 TREE_SIDE_EFFECTS (t) = 1;
5836 return convert_from_reference (t);
5839 return build_const_cast_1 (type, expr, complain & tf_error,
5843 /* Like cp_build_c_cast, but for the c-common bits. */
5846 build_c_cast (location_t loc ATTRIBUTE_UNUSED, tree type, tree expr)
5848 return cp_build_c_cast (type, expr, tf_warning_or_error);
5851 /* Build an expression representing an explicit C-style cast to type
5852 TYPE of expression EXPR. */
5855 cp_build_c_cast (tree type, tree expr, tsubst_flags_t complain)
5861 if (type == error_mark_node || error_operand_p (expr))
5862 return error_mark_node;
5864 if (processing_template_decl)
5866 tree t = build_min (CAST_EXPR, type,
5867 tree_cons (NULL_TREE, value, NULL_TREE));
5868 /* We don't know if it will or will not have side effects. */
5869 TREE_SIDE_EFFECTS (t) = 1;
5870 return convert_from_reference (t);
5873 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5874 'Class') should always be retained, because this information aids
5875 in method lookup. */
5876 if (objc_is_object_ptr (type)
5877 && objc_is_object_ptr (TREE_TYPE (expr)))
5878 return build_nop (type, expr);
5880 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5881 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5882 if (TREE_CODE (type) != REFERENCE_TYPE
5883 && TREE_CODE (value) == NOP_EXPR
5884 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5885 value = TREE_OPERAND (value, 0);
5887 if (TREE_CODE (type) == ARRAY_TYPE)
5889 /* Allow casting from T1* to T2[] because Cfront allows it.
5890 NIHCL uses it. It is not valid ISO C++ however. */
5891 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5893 if (complain & tf_error)
5894 permerror (input_location, "ISO C++ forbids casting to an array type %qT", type);
5896 return error_mark_node;
5897 type = build_pointer_type (TREE_TYPE (type));
5901 if (complain & tf_error)
5902 error ("ISO C++ forbids casting to an array type %qT", type);
5903 return error_mark_node;
5907 if (TREE_CODE (type) == FUNCTION_TYPE
5908 || TREE_CODE (type) == METHOD_TYPE)
5910 if (complain & tf_error)
5911 error ("invalid cast to function type %qT", type);
5912 return error_mark_node;
5915 /* A C-style cast can be a const_cast. */
5916 result = build_const_cast_1 (type, value, /*complain=*/false,
5921 /* Or a static cast. */
5922 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5923 &valid_p, complain);
5924 /* Or a reinterpret_cast. */
5926 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5927 &valid_p, complain);
5928 /* The static_cast or reinterpret_cast may be followed by a
5931 /* A valid cast may result in errors if, for example, a
5932 conversion to am ambiguous base class is required. */
5933 && !error_operand_p (result))
5937 /* Non-class rvalues always have cv-unqualified type. */
5938 if (!CLASS_TYPE_P (type))
5939 type = TYPE_MAIN_VARIANT (type);
5940 result_type = TREE_TYPE (result);
5941 if (!CLASS_TYPE_P (result_type))
5942 result_type = TYPE_MAIN_VARIANT (result_type);
5943 /* If the type of RESULT does not match TYPE, perform a
5944 const_cast to make it match. If the static_cast or
5945 reinterpret_cast succeeded, we will differ by at most
5946 cv-qualification, so the follow-on const_cast is guaranteed
5948 if (!same_type_p (non_reference (type), non_reference (result_type)))
5950 result = build_const_cast_1 (type, result, false, &valid_p);
5951 gcc_assert (valid_p);
5956 return error_mark_node;
5959 /* For use from the C common bits. */
5961 build_modify_expr (location_t location ATTRIBUTE_UNUSED,
5962 tree lhs, tree lhs_origtype ATTRIBUTE_UNUSED,
5963 enum tree_code modifycode,
5964 location_t rhs_location ATTRIBUTE_UNUSED, tree rhs,
5965 tree rhs_origtype ATTRIBUTE_UNUSED)
5967 return cp_build_modify_expr (lhs, modifycode, rhs, tf_warning_or_error);
5970 /* Build an assignment expression of lvalue LHS from value RHS.
5971 MODIFYCODE is the code for a binary operator that we use
5972 to combine the old value of LHS with RHS to get the new value.
5973 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5975 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5978 cp_build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
5979 tsubst_flags_t complain)
5983 tree lhstype = TREE_TYPE (lhs);
5984 tree olhstype = lhstype;
5985 bool plain_assign = (modifycode == NOP_EXPR);
5987 /* Avoid duplicate error messages from operands that had errors. */
5988 if (error_operand_p (lhs) || error_operand_p (rhs))
5989 return error_mark_node;
5991 /* Handle control structure constructs used as "lvalues". */
5992 switch (TREE_CODE (lhs))
5994 /* Handle --foo = 5; as these are valid constructs in C++. */
5995 case PREDECREMENT_EXPR:
5996 case PREINCREMENT_EXPR:
5997 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5998 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5999 stabilize_reference (TREE_OPERAND (lhs, 0)),
6000 TREE_OPERAND (lhs, 1));
6001 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0),
6002 modifycode, rhs, complain);
6003 if (newrhs == error_mark_node)
6004 return error_mark_node;
6005 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
6007 /* Handle (a, b) used as an "lvalue". */
6009 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6010 modifycode, rhs, complain);
6011 if (newrhs == error_mark_node)
6012 return error_mark_node;
6013 return build2 (COMPOUND_EXPR, lhstype,
6014 TREE_OPERAND (lhs, 0), newrhs);
6017 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
6018 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
6019 stabilize_reference (TREE_OPERAND (lhs, 0)),
6020 TREE_OPERAND (lhs, 1));
6021 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs,
6023 if (newrhs == error_mark_node)
6024 return error_mark_node;
6025 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
6029 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
6030 when neither operand has side-effects. */
6031 if (!lvalue_or_else (lhs, lv_assign, complain))
6032 return error_mark_node;
6034 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
6035 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
6037 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
6038 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
6040 TREE_OPERAND (lhs, 0),
6041 TREE_OPERAND (lhs, 1)),
6042 TREE_OPERAND (lhs, 0),
6043 TREE_OPERAND (lhs, 1));
6046 /* Handle (a ? b : c) used as an "lvalue". */
6049 /* Produce (a ? (b = rhs) : (c = rhs))
6050 except that the RHS goes through a save-expr
6051 so the code to compute it is only emitted once. */
6053 tree preeval = NULL_TREE;
6055 if (VOID_TYPE_P (TREE_TYPE (rhs)))
6057 if (complain & tf_error)
6058 error ("void value not ignored as it ought to be");
6059 return error_mark_node;
6062 rhs = stabilize_expr (rhs, &preeval);
6064 /* Check this here to avoid odd errors when trying to convert
6065 a throw to the type of the COND_EXPR. */
6066 if (!lvalue_or_else (lhs, lv_assign, complain))
6067 return error_mark_node;
6069 cond = build_conditional_expr
6070 (TREE_OPERAND (lhs, 0),
6071 cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6072 modifycode, rhs, complain),
6073 cp_build_modify_expr (TREE_OPERAND (lhs, 2),
6074 modifycode, rhs, complain),
6077 if (cond == error_mark_node)
6079 /* Make sure the code to compute the rhs comes out
6080 before the split. */
6082 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
6090 if (modifycode == INIT_EXPR)
6092 if (BRACE_ENCLOSED_INITIALIZER_P (rhs))
6093 /* Do the default thing. */;
6094 else if (TREE_CODE (rhs) == CONSTRUCTOR)
6096 /* Compound literal. */
6097 if (! same_type_p (TREE_TYPE (rhs), lhstype))
6098 /* Call convert to generate an error; see PR 11063. */
6099 rhs = convert (lhstype, rhs);
6100 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
6101 TREE_SIDE_EFFECTS (result) = 1;
6104 else if (! MAYBE_CLASS_TYPE_P (lhstype))
6105 /* Do the default thing. */;
6108 VEC(tree,gc) *rhs_vec = make_tree_vector_single (rhs);
6109 result = build_special_member_call (lhs, complete_ctor_identifier,
6110 &rhs_vec, lhstype, LOOKUP_NORMAL,
6112 release_tree_vector (rhs_vec);
6113 if (result == NULL_TREE)
6114 return error_mark_node;
6120 lhs = require_complete_type (lhs);
6121 if (lhs == error_mark_node)
6122 return error_mark_node;
6124 if (modifycode == NOP_EXPR)
6126 /* `operator=' is not an inheritable operator. */
6127 if (! MAYBE_CLASS_TYPE_P (lhstype))
6128 /* Do the default thing. */;
6131 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
6132 lhs, rhs, make_node (NOP_EXPR),
6133 /*overloaded_p=*/NULL,
6135 if (result == NULL_TREE)
6136 return error_mark_node;
6143 /* A binary op has been requested. Combine the old LHS
6144 value with the RHS producing the value we should actually
6145 store into the LHS. */
6146 gcc_assert (!((TREE_CODE (lhstype) == REFERENCE_TYPE
6147 && MAYBE_CLASS_TYPE_P (TREE_TYPE (lhstype)))
6148 || MAYBE_CLASS_TYPE_P (lhstype)));
6150 lhs = stabilize_reference (lhs);
6151 newrhs = cp_build_binary_op (input_location,
6152 modifycode, lhs, rhs,
6154 if (newrhs == error_mark_node)
6156 if (complain & tf_error)
6157 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
6158 TREE_TYPE (lhs), TREE_TYPE (rhs));
6159 return error_mark_node;
6162 /* Now it looks like a plain assignment. */
6163 modifycode = NOP_EXPR;
6165 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
6166 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
6169 /* The left-hand side must be an lvalue. */
6170 if (!lvalue_or_else (lhs, lv_assign, complain))
6171 return error_mark_node;
6173 /* Warn about modifying something that is `const'. Don't warn if
6174 this is initialization. */
6175 if (modifycode != INIT_EXPR
6176 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
6177 /* Functions are not modifiable, even though they are
6179 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
6180 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
6181 /* If it's an aggregate and any field is const, then it is
6182 effectively const. */
6183 || (CLASS_TYPE_P (lhstype)
6184 && C_TYPE_FIELDS_READONLY (lhstype))))
6186 if (complain & tf_error)
6187 readonly_error (lhs, "assignment");
6189 return error_mark_node;
6192 /* If storing into a structure or union member, it may have been given a
6193 lowered bitfield type. We need to convert to the declared type first,
6194 so retrieve it now. */
6196 olhstype = unlowered_expr_type (lhs);
6198 /* Convert new value to destination type. */
6200 if (TREE_CODE (lhstype) == ARRAY_TYPE)
6204 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
6205 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
6207 if (complain & tf_error)
6208 error ("incompatible types in assignment of %qT to %qT",
6209 TREE_TYPE (rhs), lhstype);
6210 return error_mark_node;
6213 /* Allow array assignment in compiler-generated code. */
6214 if (!current_function_decl || !DECL_ARTIFICIAL (current_function_decl))
6216 /* This routine is used for both initialization and assignment.
6217 Make sure the diagnostic message differentiates the context. */
6218 if (complain & tf_error)
6220 if (modifycode == INIT_EXPR)
6221 error ("array used as initializer");
6223 error ("invalid array assignment");
6225 return error_mark_node;
6228 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
6229 ? 1 + (modifycode != INIT_EXPR): 0;
6230 return build_vec_init (lhs, NULL_TREE, newrhs,
6231 /*explicit_value_init_p=*/false,
6232 from_array, complain);
6235 if (modifycode == INIT_EXPR)
6236 /* Calls with INIT_EXPR are all direct-initialization, so don't set
6237 LOOKUP_ONLYCONVERTING. */
6238 newrhs = convert_for_initialization (lhs, olhstype, newrhs, LOOKUP_NORMAL,
6239 "initialization", NULL_TREE, 0,
6242 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
6243 NULL_TREE, 0, complain, LOOKUP_IMPLICIT);
6245 if (!same_type_p (lhstype, olhstype))
6246 newrhs = cp_convert_and_check (lhstype, newrhs);
6248 if (modifycode != INIT_EXPR)
6250 if (TREE_CODE (newrhs) == CALL_EXPR
6251 && TYPE_NEEDS_CONSTRUCTING (lhstype))
6252 newrhs = build_cplus_new (lhstype, newrhs);
6254 /* Can't initialize directly from a TARGET_EXPR, since that would
6255 cause the lhs to be constructed twice, and possibly result in
6256 accidental self-initialization. So we force the TARGET_EXPR to be
6257 expanded without a target. */
6258 if (TREE_CODE (newrhs) == TARGET_EXPR)
6259 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
6260 TREE_OPERAND (newrhs, 0));
6263 if (newrhs == error_mark_node)
6264 return error_mark_node;
6266 if (c_dialect_objc () && flag_objc_gc)
6268 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
6274 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
6275 lhstype, lhs, newrhs);
6277 TREE_SIDE_EFFECTS (result) = 1;
6279 TREE_NO_WARNING (result) = 1;
6285 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6286 tsubst_flags_t complain)
6288 if (processing_template_decl)
6289 return build_min_nt (MODOP_EXPR, lhs,
6290 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
6292 if (modifycode != NOP_EXPR)
6294 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
6295 make_node (modifycode),
6296 /*overloaded_p=*/NULL,
6300 TREE_NO_WARNING (rval) = 1;
6304 return cp_build_modify_expr (lhs, modifycode, rhs, complain);
6307 /* Helper function for get_delta_difference which assumes FROM is a base
6308 class of TO. Returns a delta for the conversion of pointer-to-member
6309 of FROM to pointer-to-member of TO. If the conversion is invalid,
6310 returns zero. If FROM is not a base class of TO, returns NULL_TREE.
6311 If C_CAST_P is true, this conversion is taking place as part of a C-style
6315 get_delta_difference_1 (tree from, tree to, bool c_cast_p)
6320 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
6321 if (kind == bk_inaccessible || kind == bk_ambig)
6323 error (" in pointer to member function conversion");
6324 return size_zero_node;
6328 if (kind != bk_via_virtual)
6329 return BINFO_OFFSET (binfo);
6331 /* FROM is a virtual base class of TO. Issue an error or warning
6332 depending on whether or not this is a reinterpret cast. */
6334 error ("pointer to member conversion via virtual base %qT",
6335 BINFO_TYPE (binfo_from_vbase (binfo)));
6337 return size_zero_node;
6344 /* Get difference in deltas for different pointer to member function
6345 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
6346 the conversion is invalid, the constant is zero. If
6347 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
6348 If C_CAST_P is true this conversion is taking place as part of a
6351 Note that the naming of FROM and TO is kind of backwards; the return
6352 value is what we add to a TO in order to get a FROM. They are named
6353 this way because we call this function to find out how to convert from
6354 a pointer to member of FROM to a pointer to member of TO. */
6357 get_delta_difference (tree from, tree to,
6358 bool allow_inverse_p,
6363 if (same_type_ignoring_top_level_qualifiers_p (from, to))
6364 /* Pointer to member of incomplete class is permitted*/
6365 result = size_zero_node;
6367 result = get_delta_difference_1 (from, to, c_cast_p);
6371 if (!allow_inverse_p)
6373 error_not_base_type (from, to);
6374 error (" in pointer to member conversion");
6375 result = size_zero_node;
6379 result = get_delta_difference_1 (to, from, c_cast_p);
6382 result = size_diffop (size_zero_node, result);
6385 error_not_base_type (from, to);
6386 error (" in pointer to member conversion");
6387 result = size_zero_node;
6392 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
6396 /* Return a constructor for the pointer-to-member-function TYPE using
6397 the other components as specified. */
6400 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
6405 VEC(constructor_elt, gc) *v;
6407 /* Pull the FIELD_DECLs out of the type. */
6408 pfn_field = TYPE_FIELDS (type);
6409 delta_field = TREE_CHAIN (pfn_field);
6411 /* Make sure DELTA has the type we want. */
6412 delta = convert_and_check (delta_type_node, delta);
6414 /* Convert to the correct target type if necessary. */
6415 pfn = fold_convert (TREE_TYPE (pfn_field), pfn);
6417 /* Finish creating the initializer. */
6418 v = VEC_alloc(constructor_elt, gc, 2);
6419 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
6420 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
6421 u = build_constructor (type, v);
6422 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
6423 TREE_STATIC (u) = (TREE_CONSTANT (u)
6424 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
6426 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
6431 /* Build a constructor for a pointer to member function. It can be
6432 used to initialize global variables, local variable, or used
6433 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
6436 If FORCE is nonzero, then force this conversion, even if
6437 we would rather not do it. Usually set when using an explicit
6438 cast. A C-style cast is being processed iff C_CAST_P is true.
6440 Return error_mark_node, if something goes wrong. */
6443 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
6449 if (error_operand_p (pfn))
6450 return error_mark_node;
6452 pfn_type = TREE_TYPE (pfn);
6453 to_type = build_ptrmemfunc_type (type);
6455 /* Handle multiple conversions of pointer to member functions. */
6456 if (TYPE_PTRMEMFUNC_P (pfn_type))
6458 tree delta = NULL_TREE;
6459 tree npfn = NULL_TREE;
6463 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
6464 error ("invalid conversion to type %qT from type %qT",
6467 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
6468 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
6472 /* We don't have to do any conversion to convert a
6473 pointer-to-member to its own type. But, we don't want to
6474 just return a PTRMEM_CST if there's an explicit cast; that
6475 cast should make the expression an invalid template argument. */
6476 if (TREE_CODE (pfn) != PTRMEM_CST)
6478 if (same_type_p (to_type, pfn_type))
6480 else if (integer_zerop (n))
6481 return build_reinterpret_cast (to_type, pfn,
6482 tf_warning_or_error);
6485 if (TREE_SIDE_EFFECTS (pfn))
6486 pfn = save_expr (pfn);
6488 /* Obtain the function pointer and the current DELTA. */
6489 if (TREE_CODE (pfn) == PTRMEM_CST)
6490 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
6493 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
6494 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
6497 /* Just adjust the DELTA field. */
6498 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6499 (TREE_TYPE (delta), ptrdiff_type_node));
6500 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
6501 n = cp_build_binary_op (input_location,
6502 LSHIFT_EXPR, n, integer_one_node,
6503 tf_warning_or_error);
6504 delta = cp_build_binary_op (input_location,
6505 PLUS_EXPR, delta, n, tf_warning_or_error);
6506 return build_ptrmemfunc1 (to_type, delta, npfn);
6509 /* Handle null pointer to member function conversions. */
6510 if (integer_zerop (pfn))
6512 pfn = build_c_cast (input_location, type, integer_zero_node);
6513 return build_ptrmemfunc1 (to_type,
6518 if (type_unknown_p (pfn))
6519 return instantiate_type (type, pfn, tf_warning_or_error);
6521 fn = TREE_OPERAND (pfn, 0);
6522 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
6523 /* In a template, we will have preserved the
6525 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
6526 return make_ptrmem_cst (to_type, fn);
6529 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
6532 ??? There is no consistency as to the types returned for the above
6533 values. Some code acts as if it were a sizetype and some as if it were
6534 integer_type_node. */
6537 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
6539 tree type = TREE_TYPE (cst);
6540 tree fn = PTRMEM_CST_MEMBER (cst);
6541 tree ptr_class, fn_class;
6543 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6545 /* The class that the function belongs to. */
6546 fn_class = DECL_CONTEXT (fn);
6548 /* The class that we're creating a pointer to member of. */
6549 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
6551 /* First, calculate the adjustment to the function's class. */
6552 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
6555 if (!DECL_VIRTUAL_P (fn))
6556 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
6559 /* If we're dealing with a virtual function, we have to adjust 'this'
6560 again, to point to the base which provides the vtable entry for
6561 fn; the call will do the opposite adjustment. */
6562 tree orig_class = DECL_CONTEXT (fn);
6563 tree binfo = binfo_or_else (orig_class, fn_class);
6564 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6565 *delta, BINFO_OFFSET (binfo));
6566 *delta = fold_if_not_in_template (*delta);
6568 /* We set PFN to the vtable offset at which the function can be
6569 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6570 case delta is shifted left, and then incremented). */
6571 *pfn = DECL_VINDEX (fn);
6572 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
6573 TYPE_SIZE_UNIT (vtable_entry_type));
6574 *pfn = fold_if_not_in_template (*pfn);
6576 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
6578 case ptrmemfunc_vbit_in_pfn:
6579 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6581 *pfn = fold_if_not_in_template (*pfn);
6584 case ptrmemfunc_vbit_in_delta:
6585 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6586 *delta, integer_one_node);
6587 *delta = fold_if_not_in_template (*delta);
6588 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6589 *delta, integer_one_node);
6590 *delta = fold_if_not_in_template (*delta);
6597 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6598 *pfn = fold_if_not_in_template (*pfn);
6602 /* Return an expression for PFN from the pointer-to-member function
6606 pfn_from_ptrmemfunc (tree t)
6608 if (TREE_CODE (t) == PTRMEM_CST)
6613 expand_ptrmemfunc_cst (t, &delta, &pfn);
6618 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6621 /* Return an expression for DELTA from the pointer-to-member function
6625 delta_from_ptrmemfunc (tree t)
6627 if (TREE_CODE (t) == PTRMEM_CST)
6632 expand_ptrmemfunc_cst (t, &delta, &pfn);
6637 return build_ptrmemfunc_access_expr (t, delta_identifier);
6640 /* Convert value RHS to type TYPE as preparation for an assignment to
6641 an lvalue of type TYPE. ERRTYPE is a string to use in error
6642 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6643 are doing the conversion in order to pass the PARMNUMth argument of
6647 convert_for_assignment (tree type, tree rhs,
6648 const char *errtype, tree fndecl, int parmnum,
6649 tsubst_flags_t complain, int flags)
6652 enum tree_code coder;
6654 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6655 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6656 rhs = TREE_OPERAND (rhs, 0);
6658 rhstype = TREE_TYPE (rhs);
6659 coder = TREE_CODE (rhstype);
6661 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6662 && vector_types_convertible_p (type, rhstype, true))
6663 return convert (type, rhs);
6665 if (rhs == error_mark_node || rhstype == error_mark_node)
6666 return error_mark_node;
6667 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6668 return error_mark_node;
6670 /* The RHS of an assignment cannot have void type. */
6671 if (coder == VOID_TYPE)
6673 if (complain & tf_error)
6674 error ("void value not ignored as it ought to be");
6675 return error_mark_node;
6678 /* Simplify the RHS if possible. */
6679 if (TREE_CODE (rhs) == CONST_DECL)
6680 rhs = DECL_INITIAL (rhs);
6682 if (c_dialect_objc ())
6685 tree rname = fndecl;
6687 if (!strcmp (errtype, "assignment"))
6689 else if (!strcmp (errtype, "initialization"))
6693 tree selector = objc_message_selector ();
6697 if (selector && parmno > 1)
6704 if (objc_compare_types (type, rhstype, parmno, rname))
6705 return convert (type, rhs);
6710 The expression is implicitly converted (clause _conv_) to the
6711 cv-unqualified type of the left operand.
6713 We allow bad conversions here because by the time we get to this point
6714 we are committed to doing the conversion. If we end up doing a bad
6715 conversion, convert_like will complain. */
6716 if (!can_convert_arg_bad (type, rhstype, rhs, flags))
6718 /* When -Wno-pmf-conversions is use, we just silently allow
6719 conversions from pointers-to-members to plain pointers. If
6720 the conversion doesn't work, cp_convert will complain. */
6722 && TYPE_PTR_P (type)
6723 && TYPE_PTRMEMFUNC_P (rhstype))
6724 rhs = cp_convert (strip_top_quals (type), rhs);
6727 if (complain & tf_error)
6729 /* If the right-hand side has unknown type, then it is an
6730 overloaded function. Call instantiate_type to get error
6732 if (rhstype == unknown_type_node)
6733 instantiate_type (type, rhs, tf_warning_or_error);
6735 error ("cannot convert %qT to %qT for argument %qP to %qD",
6736 rhstype, type, parmnum, fndecl);
6738 error ("cannot convert %qT to %qT in %s", rhstype, type,
6741 return error_mark_node;
6744 if (warn_missing_format_attribute)
6746 const enum tree_code codel = TREE_CODE (type);
6747 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6749 && check_missing_format_attribute (type, rhstype)
6750 && (complain & tf_warning))
6751 warning (OPT_Wmissing_format_attribute,
6752 "%s might be a candidate for a format attribute",
6756 /* If -Wparentheses, warn about a = b = c when a has type bool and b
6758 if (warn_parentheses
6759 && type == boolean_type_node
6760 && TREE_CODE (rhs) == MODIFY_EXPR
6761 && !TREE_NO_WARNING (rhs)
6762 && TREE_TYPE (rhs) != boolean_type_node
6763 && (complain & tf_warning))
6765 warning (OPT_Wparentheses,
6766 "suggest parentheses around assignment used as truth value");
6767 TREE_NO_WARNING (rhs) = 1;
6770 return perform_implicit_conversion_flags (strip_top_quals (type), rhs,
6774 /* Convert RHS to be of type TYPE.
6775 If EXP is nonzero, it is the target of the initialization.
6776 ERRTYPE is a string to use in error messages.
6778 Two major differences between the behavior of
6779 `convert_for_assignment' and `convert_for_initialization'
6780 are that references are bashed in the former, while
6781 copied in the latter, and aggregates are assigned in
6782 the former (operator=) while initialized in the
6785 If using constructor make sure no conversion operator exists, if one does
6786 exist, an ambiguity exists.
6788 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6791 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6792 const char *errtype, tree fndecl, int parmnum,
6793 tsubst_flags_t complain)
6795 enum tree_code codel = TREE_CODE (type);
6797 enum tree_code coder;
6799 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6800 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6801 if (TREE_CODE (rhs) == NOP_EXPR
6802 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6803 && codel != REFERENCE_TYPE)
6804 rhs = TREE_OPERAND (rhs, 0);
6806 if (type == error_mark_node
6807 || rhs == error_mark_node
6808 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6809 return error_mark_node;
6811 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6812 && TREE_CODE (type) != ARRAY_TYPE
6813 && (TREE_CODE (type) != REFERENCE_TYPE
6814 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6815 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6816 && (TREE_CODE (type) != REFERENCE_TYPE
6817 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6818 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6819 rhs = decay_conversion (rhs);
6821 rhstype = TREE_TYPE (rhs);
6822 coder = TREE_CODE (rhstype);
6824 if (coder == ERROR_MARK)
6825 return error_mark_node;
6827 /* We accept references to incomplete types, so we can
6828 return here before checking if RHS is of complete type. */
6830 if (codel == REFERENCE_TYPE)
6832 /* This should eventually happen in convert_arguments. */
6833 int savew = 0, savee = 0;
6836 savew = warningcount, savee = errorcount;
6837 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6841 if (warningcount > savew)
6842 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6843 else if (errorcount > savee)
6844 error ("in passing argument %P of %q+D", parmnum, fndecl);
6850 exp = require_complete_type (exp);
6851 if (exp == error_mark_node)
6852 return error_mark_node;
6854 rhstype = non_reference (rhstype);
6856 type = complete_type (type);
6858 if (MAYBE_CLASS_TYPE_P (type))
6859 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6861 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum,
6865 /* If RETVAL is the address of, or a reference to, a local variable or
6866 temporary give an appropriate warning. */
6869 maybe_warn_about_returning_address_of_local (tree retval)
6871 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6872 tree whats_returned = retval;
6876 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6877 whats_returned = TREE_OPERAND (whats_returned, 1);
6878 else if (CONVERT_EXPR_P (whats_returned)
6879 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR)
6880 whats_returned = TREE_OPERAND (whats_returned, 0);
6885 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6887 whats_returned = TREE_OPERAND (whats_returned, 0);
6889 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6891 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6892 || TREE_CODE (whats_returned) == TARGET_EXPR)
6894 warning (0, "returning reference to temporary");
6897 if (TREE_CODE (whats_returned) == VAR_DECL
6898 && DECL_NAME (whats_returned)
6899 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6901 warning (0, "reference to non-lvalue returned");
6906 while (TREE_CODE (whats_returned) == COMPONENT_REF
6907 || TREE_CODE (whats_returned) == ARRAY_REF)
6908 whats_returned = TREE_OPERAND (whats_returned, 0);
6910 if (DECL_P (whats_returned)
6911 && DECL_NAME (whats_returned)
6912 && DECL_FUNCTION_SCOPE_P (whats_returned)
6913 && !(TREE_STATIC (whats_returned)
6914 || TREE_PUBLIC (whats_returned)))
6916 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6917 warning (0, "reference to local variable %q+D returned",
6920 warning (0, "address of local variable %q+D returned",
6926 /* Check that returning RETVAL from the current function is valid.
6927 Return an expression explicitly showing all conversions required to
6928 change RETVAL into the function return type, and to assign it to
6929 the DECL_RESULT for the function. Set *NO_WARNING to true if
6930 code reaches end of non-void function warning shouldn't be issued
6931 on this RETURN_EXPR. */
6934 check_return_expr (tree retval, bool *no_warning)
6937 /* The type actually returned by the function, after any
6940 int fn_returns_value_p;
6941 bool named_return_value_okay_p;
6943 *no_warning = false;
6945 /* A `volatile' function is one that isn't supposed to return, ever.
6946 (This is a G++ extension, used to get better code for functions
6947 that call the `volatile' function.) */
6948 if (TREE_THIS_VOLATILE (current_function_decl))
6949 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6951 /* Check for various simple errors. */
6952 if (DECL_DESTRUCTOR_P (current_function_decl))
6955 error ("returning a value from a destructor");
6958 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6960 if (in_function_try_handler)
6961 /* If a return statement appears in a handler of the
6962 function-try-block of a constructor, the program is ill-formed. */
6963 error ("cannot return from a handler of a function-try-block of a constructor");
6965 /* You can't return a value from a constructor. */
6966 error ("returning a value from a constructor");
6970 if (processing_template_decl)
6972 current_function_returns_value = 1;
6973 if (check_for_bare_parameter_packs (retval))
6974 retval = error_mark_node;
6978 /* When no explicit return-value is given in a function with a named
6979 return value, the named return value is used. */
6980 result = DECL_RESULT (current_function_decl);
6981 valtype = TREE_TYPE (result);
6982 gcc_assert (valtype != NULL_TREE);
6983 fn_returns_value_p = !VOID_TYPE_P (valtype);
6984 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6987 /* Check for a return statement with no return value in a function
6988 that's supposed to return a value. */
6989 if (!retval && fn_returns_value_p)
6991 permerror (input_location, "return-statement with no value, in function returning %qT",
6993 /* Clear this, so finish_function won't say that we reach the
6994 end of a non-void function (which we don't, we gave a
6996 current_function_returns_null = 0;
6997 /* And signal caller that TREE_NO_WARNING should be set on the
6998 RETURN_EXPR to avoid control reaches end of non-void function
6999 warnings in tree-cfg.c. */
7002 /* Check for a return statement with a value in a function that
7003 isn't supposed to return a value. */
7004 else if (retval && !fn_returns_value_p)
7006 if (VOID_TYPE_P (TREE_TYPE (retval)))
7007 /* You can return a `void' value from a function of `void'
7008 type. In that case, we have to evaluate the expression for
7009 its side-effects. */
7010 finish_expr_stmt (retval);
7012 permerror (input_location, "return-statement with a value, in function "
7013 "returning 'void'");
7014 current_function_returns_null = 1;
7016 /* There's really no value to return, after all. */
7020 /* Remember that this function can sometimes return without a
7022 current_function_returns_null = 1;
7024 /* Remember that this function did return a value. */
7025 current_function_returns_value = 1;
7027 /* Check for erroneous operands -- but after giving ourselves a
7028 chance to provide an error about returning a value from a void
7030 if (error_operand_p (retval))
7032 current_function_return_value = error_mark_node;
7033 return error_mark_node;
7036 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
7037 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
7038 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
7039 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
7041 && retval && null_ptr_cst_p (retval))
7042 warning (0, "%<operator new%> must not return NULL unless it is "
7043 "declared %<throw()%> (or -fcheck-new is in effect)");
7045 /* Effective C++ rule 15. See also start_function. */
7047 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
7051 /* The function return type must be a reference to the current
7053 if (TREE_CODE (valtype) == REFERENCE_TYPE
7054 && same_type_ignoring_top_level_qualifiers_p
7055 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
7057 /* Returning '*this' is obviously OK. */
7058 if (retval == current_class_ref)
7060 /* If we are calling a function whose return type is the same of
7061 the current class reference, it is ok. */
7062 else if (TREE_CODE (retval) == INDIRECT_REF
7063 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
7068 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
7071 /* The fabled Named Return Value optimization, as per [class.copy]/15:
7073 [...] For a function with a class return type, if the expression
7074 in the return statement is the name of a local object, and the cv-
7075 unqualified type of the local object is the same as the function
7076 return type, an implementation is permitted to omit creating the tem-
7077 porary object to hold the function return value [...]
7079 So, if this is a value-returning function that always returns the same
7080 local variable, remember it.
7082 It might be nice to be more flexible, and choose the first suitable
7083 variable even if the function sometimes returns something else, but
7084 then we run the risk of clobbering the variable we chose if the other
7085 returned expression uses the chosen variable somehow. And people expect
7086 this restriction, anyway. (jason 2000-11-19)
7088 See finish_function and finalize_nrv for the rest of this optimization. */
7090 named_return_value_okay_p =
7091 (retval != NULL_TREE
7092 /* Must be a local, automatic variable. */
7093 && TREE_CODE (retval) == VAR_DECL
7094 && DECL_CONTEXT (retval) == current_function_decl
7095 && ! TREE_STATIC (retval)
7096 && ! DECL_ANON_UNION_VAR_P (retval)
7097 && (DECL_ALIGN (retval)
7098 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
7099 /* The cv-unqualified type of the returned value must be the
7100 same as the cv-unqualified return type of the
7102 && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))),
7104 (TREE_TYPE (TREE_TYPE (current_function_decl)))))
7105 /* And the returned value must be non-volatile. */
7106 && ! TYPE_VOLATILE (TREE_TYPE (retval)));
7108 if (fn_returns_value_p && flag_elide_constructors)
7110 if (named_return_value_okay_p
7111 && (current_function_return_value == NULL_TREE
7112 || current_function_return_value == retval))
7113 current_function_return_value = retval;
7115 current_function_return_value = error_mark_node;
7118 /* We don't need to do any conversions when there's nothing being
7123 /* Do any required conversions. */
7124 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
7125 /* No conversions are required. */
7129 /* The type the function is declared to return. */
7130 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
7131 int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
7133 /* The functype's return type will have been set to void, if it
7134 was an incomplete type. Just treat this as 'return;' */
7135 if (VOID_TYPE_P (functype))
7136 return error_mark_node;
7138 /* Under C++0x [12.8/16 class.copy], a returned lvalue is sometimes
7139 treated as an rvalue for the purposes of overload resolution to
7140 favor move constructors over copy constructors. */
7141 if ((cxx_dialect != cxx98)
7142 && named_return_value_okay_p
7143 /* The variable must not have the `volatile' qualifier. */
7144 && !(cp_type_quals (TREE_TYPE (retval)) & TYPE_QUAL_VOLATILE)
7145 /* The return type must be a class type. */
7146 && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
7147 flags = flags | LOOKUP_PREFER_RVALUE;
7149 /* First convert the value to the function's return type, then
7150 to the type of return value's location to handle the
7151 case that functype is smaller than the valtype. */
7152 retval = convert_for_initialization
7153 (NULL_TREE, functype, retval, flags, "return", NULL_TREE, 0,
7154 tf_warning_or_error);
7155 retval = convert (valtype, retval);
7157 /* If the conversion failed, treat this just like `return;'. */
7158 if (retval == error_mark_node)
7160 /* We can't initialize a register from a AGGR_INIT_EXPR. */
7161 else if (! cfun->returns_struct
7162 && TREE_CODE (retval) == TARGET_EXPR
7163 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
7164 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
7165 TREE_OPERAND (retval, 0));
7167 maybe_warn_about_returning_address_of_local (retval);
7170 /* Actually copy the value returned into the appropriate location. */
7171 if (retval && retval != result)
7172 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
7178 /* Returns nonzero if the pointer-type FROM can be converted to the
7179 pointer-type TO via a qualification conversion. If CONSTP is -1,
7180 then we return nonzero if the pointers are similar, and the
7181 cv-qualification signature of FROM is a proper subset of that of TO.
7183 If CONSTP is positive, then all outer pointers have been
7187 comp_ptr_ttypes_real (tree to, tree from, int constp)
7189 bool to_more_cv_qualified = false;
7190 bool is_opaque_pointer = false;
7192 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7194 if (TREE_CODE (to) != TREE_CODE (from))
7197 if (TREE_CODE (from) == OFFSET_TYPE
7198 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
7199 TYPE_OFFSET_BASETYPE (to)))
7202 /* Const and volatile mean something different for function types,
7203 so the usual checks are not appropriate. */
7204 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
7206 /* In Objective-C++, some types may have been 'volatilized' by
7207 the compiler for EH; when comparing them here, the volatile
7208 qualification must be ignored. */
7209 bool objc_quals_match = objc_type_quals_match (to, from);
7211 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
7214 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
7218 to_more_cv_qualified = true;
7222 constp &= TYPE_READONLY (to);
7225 if (TREE_CODE (to) == VECTOR_TYPE)
7226 is_opaque_pointer = vector_targets_convertible_p (to, from);
7228 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
7229 return ((constp >= 0 || to_more_cv_qualified)
7230 && (is_opaque_pointer
7231 || same_type_ignoring_top_level_qualifiers_p (to, from)));
7235 /* When comparing, say, char ** to char const **, this function takes
7236 the 'char *' and 'char const *'. Do not pass non-pointer/reference
7237 types to this function. */
7240 comp_ptr_ttypes (tree to, tree from)
7242 return comp_ptr_ttypes_real (to, from, 1);
7245 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
7246 type or inheritance-related types, regardless of cv-quals. */
7249 ptr_reasonably_similar (const_tree to, const_tree from)
7251 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7253 /* Any target type is similar enough to void. */
7254 if (TREE_CODE (to) == VOID_TYPE
7255 || TREE_CODE (from) == VOID_TYPE)
7258 if (TREE_CODE (to) != TREE_CODE (from))
7261 if (TREE_CODE (from) == OFFSET_TYPE
7262 && comptypes (TYPE_OFFSET_BASETYPE (to),
7263 TYPE_OFFSET_BASETYPE (from),
7264 COMPARE_BASE | COMPARE_DERIVED))
7267 if (TREE_CODE (to) == VECTOR_TYPE
7268 && vector_types_convertible_p (to, from, false))
7271 if (TREE_CODE (to) == INTEGER_TYPE
7272 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
7275 if (TREE_CODE (to) == FUNCTION_TYPE)
7278 if (TREE_CODE (to) != POINTER_TYPE)
7280 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
7281 COMPARE_BASE | COMPARE_DERIVED);
7285 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
7286 pointer-to-member types) are the same, ignoring cv-qualification at
7290 comp_ptr_ttypes_const (tree to, tree from)
7292 bool is_opaque_pointer = false;
7294 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7296 if (TREE_CODE (to) != TREE_CODE (from))
7299 if (TREE_CODE (from) == OFFSET_TYPE
7300 && same_type_p (TYPE_OFFSET_BASETYPE (from),
7301 TYPE_OFFSET_BASETYPE (to)))
7304 if (TREE_CODE (to) == VECTOR_TYPE)
7305 is_opaque_pointer = vector_targets_convertible_p (to, from);
7307 if (TREE_CODE (to) != POINTER_TYPE)
7308 return (is_opaque_pointer
7309 || same_type_ignoring_top_level_qualifiers_p (to, from));
7313 /* Returns the type qualifiers for this type, including the qualifiers on the
7314 elements for an array type. */
7317 cp_type_quals (const_tree type)
7319 /* This CONST_CAST is okay because strip_array_types returns its
7320 argument unmodified and we assign it to a const_tree. */
7321 type = strip_array_types (CONST_CAST_TREE(type));
7322 if (type == error_mark_node)
7323 return TYPE_UNQUALIFIED;
7324 return TYPE_QUALS (type);
7327 /* Returns nonzero if the TYPE is const from a C++ perspective: look inside
7331 cp_type_readonly (const_tree type)
7333 /* This CONST_CAST is okay because strip_array_types returns its
7334 argument unmodified and we assign it to a const_tree. */
7335 type = strip_array_types (CONST_CAST_TREE(type));
7336 return TYPE_READONLY (type);
7339 /* Returns nonzero if the TYPE contains a mutable member. */
7342 cp_has_mutable_p (const_tree type)
7344 /* This CONST_CAST is okay because strip_array_types returns its
7345 argument unmodified and we assign it to a const_tree. */
7346 type = strip_array_types (CONST_CAST_TREE(type));
7348 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
7351 /* Set TREE_READONLY and TREE_VOLATILE on DECL as indicated by the
7352 TYPE_QUALS. For a VAR_DECL, this may be an optimistic
7353 approximation. In particular, consider:
7356 struct S { int i; };
7357 const S s = { f(); }
7359 Here, we will make "s" as TREE_READONLY (because it is declared
7360 "const") -- only to reverse ourselves upon seeing that the
7361 initializer is non-constant. */
7364 cp_apply_type_quals_to_decl (int type_quals, tree decl)
7366 tree type = TREE_TYPE (decl);
7368 if (type == error_mark_node)
7371 if (TREE_CODE (decl) == TYPE_DECL)
7374 if (TREE_CODE (type) == FUNCTION_TYPE
7375 && type_quals != TYPE_UNQUALIFIED)
7377 /* This was an error in C++98 (cv-qualifiers cannot be added to
7378 a function type), but DR 295 makes the code well-formed by
7379 dropping the extra qualifiers. */
7382 tree bad_type = build_qualified_type (type, type_quals);
7383 pedwarn (input_location, OPT_pedantic,
7384 "ignoring %qV qualifiers added to function type %qT",
7388 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
7392 /* Avoid setting TREE_READONLY incorrectly. */
7393 if (/* If the object has a constructor, the constructor may modify
7395 TYPE_NEEDS_CONSTRUCTING (type)
7396 /* If the type isn't complete, we don't know yet if it will need
7398 || !COMPLETE_TYPE_P (type)
7399 /* If the type has a mutable component, that component might be
7401 || TYPE_HAS_MUTABLE_P (type))
7402 type_quals &= ~TYPE_QUAL_CONST;
7404 c_apply_type_quals_to_decl (type_quals, decl);
7407 /* Subroutine of casts_away_constness. Make T1 and T2 point at
7408 exemplar types such that casting T1 to T2 is casting away constness
7409 if and only if there is no implicit conversion from T1 to T2. */
7412 casts_away_constness_r (tree *t1, tree *t2)
7417 /* [expr.const.cast]
7419 For multi-level pointer to members and multi-level mixed pointers
7420 and pointers to members (conv.qual), the "member" aspect of a
7421 pointer to member level is ignored when determining if a const
7422 cv-qualifier has been cast away. */
7423 /* [expr.const.cast]
7425 For two pointer types:
7427 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
7428 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
7431 casting from X1 to X2 casts away constness if, for a non-pointer
7432 type T there does not exist an implicit conversion (clause
7435 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
7439 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
7440 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
7441 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
7443 *t1 = cp_build_qualified_type (void_type_node,
7444 cp_type_quals (*t1));
7445 *t2 = cp_build_qualified_type (void_type_node,
7446 cp_type_quals (*t2));
7450 quals1 = cp_type_quals (*t1);
7451 quals2 = cp_type_quals (*t2);
7453 if (TYPE_PTRMEM_P (*t1))
7454 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
7456 *t1 = TREE_TYPE (*t1);
7457 if (TYPE_PTRMEM_P (*t2))
7458 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
7460 *t2 = TREE_TYPE (*t2);
7462 casts_away_constness_r (t1, t2);
7463 *t1 = build_pointer_type (*t1);
7464 *t2 = build_pointer_type (*t2);
7465 *t1 = cp_build_qualified_type (*t1, quals1);
7466 *t2 = cp_build_qualified_type (*t2, quals2);
7469 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
7472 ??? This function returns non-zero if casting away qualifiers not
7473 just const. We would like to return to the caller exactly which
7474 qualifiers are casted away to give more accurate diagnostics.
7478 casts_away_constness (tree t1, tree t2)
7480 if (TREE_CODE (t2) == REFERENCE_TYPE)
7482 /* [expr.const.cast]
7484 Casting from an lvalue of type T1 to an lvalue of type T2
7485 using a reference cast casts away constness if a cast from an
7486 rvalue of type "pointer to T1" to the type "pointer to T2"
7487 casts away constness. */
7488 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
7489 return casts_away_constness (build_pointer_type (t1),
7490 build_pointer_type (TREE_TYPE (t2)));
7493 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
7494 /* [expr.const.cast]
7496 Casting from an rvalue of type "pointer to data member of X
7497 of type T1" to the type "pointer to data member of Y of type
7498 T2" casts away constness if a cast from an rvalue of type
7499 "pointer to T1" to the type "pointer to T2" casts away
7501 return casts_away_constness
7502 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
7503 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
7505 /* Casting away constness is only something that makes sense for
7506 pointer or reference types. */
7507 if (TREE_CODE (t1) != POINTER_TYPE
7508 || TREE_CODE (t2) != POINTER_TYPE)
7511 /* Top-level qualifiers don't matter. */
7512 t1 = TYPE_MAIN_VARIANT (t1);
7513 t2 = TYPE_MAIN_VARIANT (t2);
7514 casts_away_constness_r (&t1, &t2);
7515 if (!can_convert (t2, t1))
7521 /* If T is a REFERENCE_TYPE return the type to which T refers.
7522 Otherwise, return T itself. */
7525 non_reference (tree t)
7527 if (TREE_CODE (t) == REFERENCE_TYPE)
7533 /* Return nonzero if REF is an lvalue valid for this language;
7534 otherwise, print an error message and return zero. USE says
7535 how the lvalue is being used and so selects the error message. */
7538 lvalue_or_else (tree ref, enum lvalue_use use, tsubst_flags_t complain)
7540 int win = lvalue_p (ref);
7542 if (!win && (complain & tf_error))