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 of the parameters. */
427 composite_pointer_type_r (tree t1, tree t2,
428 composite_pointer_operation operation,
429 tsubst_flags_t complain)
436 /* Determine the types pointed to by T1 and T2. */
437 if (TREE_CODE (t1) == POINTER_TYPE)
439 pointee1 = TREE_TYPE (t1);
440 pointee2 = TREE_TYPE (t2);
444 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
445 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
450 Otherwise, the composite pointer type is a pointer type
451 similar (_conv.qual_) to the type of one of the operands,
452 with a cv-qualification signature (_conv.qual_) that is the
453 union of the cv-qualification signatures of the operand
455 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
456 result_type = pointee1;
457 else if ((TREE_CODE (pointee1) == POINTER_TYPE
458 && TREE_CODE (pointee2) == POINTER_TYPE)
459 || (TYPE_PTR_TO_MEMBER_P (pointee1)
460 && TYPE_PTR_TO_MEMBER_P (pointee2)))
461 result_type = composite_pointer_type_r (pointee1, pointee2, operation,
465 if (complain & tf_error)
470 permerror (input_location, "comparison between "
471 "distinct pointer types %qT and %qT lacks a cast",
475 permerror (input_location, "conversion between "
476 "distinct pointer types %qT and %qT lacks a cast",
479 case CPO_CONDITIONAL_EXPR:
480 permerror (input_location, "conditional expression between "
481 "distinct pointer types %qT and %qT lacks a cast",
488 result_type = void_type_node;
490 result_type = cp_build_qualified_type (result_type,
491 (cp_type_quals (pointee1)
492 | cp_type_quals (pointee2)));
493 /* If the original types were pointers to members, so is the
495 if (TYPE_PTR_TO_MEMBER_P (t1))
497 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
498 TYPE_PTRMEM_CLASS_TYPE (t2))
499 && (complain & tf_error))
504 permerror (input_location, "comparison between "
505 "distinct pointer types %qT and %qT lacks a cast",
509 permerror (input_location, "conversion between "
510 "distinct pointer types %qT and %qT lacks a cast",
513 case CPO_CONDITIONAL_EXPR:
514 permerror (input_location, "conditional expression between "
515 "distinct pointer types %qT and %qT lacks a cast",
522 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
526 result_type = build_pointer_type (result_type);
528 /* Merge the attributes. */
529 attributes = (*targetm.merge_type_attributes) (t1, t2);
530 return build_type_attribute_variant (result_type, attributes);
533 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
534 ARG1 and ARG2 are the values with those types. The OPERATION is to
535 describe the operation between the pointer types,
536 in case an error occurs.
538 This routine also implements the computation of a common type for
539 pointers-to-members as per [expr.eq]. */
542 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
543 composite_pointer_operation operation,
544 tsubst_flags_t complain)
551 If one operand is a null pointer constant, the composite pointer
552 type is the type of the other operand. */
553 if (null_ptr_cst_p (arg1))
555 if (null_ptr_cst_p (arg2))
562 If one of the operands has type "pointer to cv1 void*", then
563 the other has type "pointer to cv2T", and the composite pointer
564 type is "pointer to cv12 void", where cv12 is the union of cv1
567 If either type is a pointer to void, make sure it is T1. */
568 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
576 /* Now, if T1 is a pointer to void, merge the qualifiers. */
577 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
582 if (TYPE_PTRFN_P (t2) && (complain & tf_error))
587 pedwarn (input_location, OPT_pedantic,
588 "ISO C++ forbids comparison between "
589 "pointer of type %<void *%> and pointer-to-function");
592 pedwarn (input_location, OPT_pedantic,
593 "ISO C++ forbids conversion between "
594 "pointer of type %<void *%> and pointer-to-function");
596 case CPO_CONDITIONAL_EXPR:
597 pedwarn (input_location, OPT_pedantic,
598 "ISO C++ forbids conditional expression between "
599 "pointer of type %<void *%> and pointer-to-function");
606 = cp_build_qualified_type (void_type_node,
607 (cp_type_quals (TREE_TYPE (t1))
608 | cp_type_quals (TREE_TYPE (t2))));
609 result_type = build_pointer_type (result_type);
610 /* Merge the attributes. */
611 attributes = (*targetm.merge_type_attributes) (t1, t2);
612 return build_type_attribute_variant (result_type, attributes);
615 if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE
616 && TREE_CODE (t2) == POINTER_TYPE)
618 if (objc_compare_types (t1, t2, -3, NULL_TREE))
622 /* [expr.eq] permits the application of a pointer conversion to
623 bring the pointers to a common type. */
624 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
625 && CLASS_TYPE_P (TREE_TYPE (t1))
626 && CLASS_TYPE_P (TREE_TYPE (t2))
627 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
630 class1 = TREE_TYPE (t1);
631 class2 = TREE_TYPE (t2);
633 if (DERIVED_FROM_P (class1, class2))
634 t2 = (build_pointer_type
635 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
636 else if (DERIVED_FROM_P (class2, class1))
637 t1 = (build_pointer_type
638 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
641 if (complain & tf_error)
645 error ("comparison between distinct "
646 "pointer types %qT and %qT lacks a cast", t1, t2);
649 error ("conversion between distinct "
650 "pointer types %qT and %qT lacks a cast", t1, t2);
652 case CPO_CONDITIONAL_EXPR:
653 error ("conditional expression between distinct "
654 "pointer types %qT and %qT lacks a cast", t1, t2);
659 return error_mark_node;
662 /* [expr.eq] permits the application of a pointer-to-member
663 conversion to change the class type of one of the types. */
664 else if (TYPE_PTR_TO_MEMBER_P (t1)
665 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
666 TYPE_PTRMEM_CLASS_TYPE (t2)))
668 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
669 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
671 if (DERIVED_FROM_P (class1, class2))
672 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
673 else if (DERIVED_FROM_P (class2, class1))
674 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
677 if (complain & tf_error)
681 error ("comparison between distinct "
682 "pointer-to-member types %qT and %qT lacks a cast",
686 error ("conversion between distinct "
687 "pointer-to-member types %qT and %qT lacks a cast",
690 case CPO_CONDITIONAL_EXPR:
691 error ("conditional expression between distinct "
692 "pointer-to-member types %qT and %qT lacks a cast",
698 return error_mark_node;
702 return composite_pointer_type_r (t1, t2, operation, complain);
705 /* Return the merged type of two types.
706 We assume that comptypes has already been done and returned 1;
707 if that isn't so, this may crash.
709 This just combines attributes and default arguments; any other
710 differences would cause the two types to compare unalike. */
713 merge_types (tree t1, tree t2)
715 enum tree_code code1;
716 enum tree_code code2;
719 /* Save time if the two types are the same. */
722 if (original_type (t1) == original_type (t2))
725 /* If one type is nonsense, use the other. */
726 if (t1 == error_mark_node)
728 if (t2 == error_mark_node)
731 /* Merge the attributes. */
732 attributes = (*targetm.merge_type_attributes) (t1, t2);
734 if (TYPE_PTRMEMFUNC_P (t1))
735 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
736 if (TYPE_PTRMEMFUNC_P (t2))
737 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
739 code1 = TREE_CODE (t1);
740 code2 = TREE_CODE (t2);
743 gcc_assert (code1 == TYPENAME_TYPE || code2 == TYPENAME_TYPE);
744 if (code1 == TYPENAME_TYPE)
746 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
747 code1 = TREE_CODE (t1);
751 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
752 code2 = TREE_CODE (t2);
760 /* For two pointers, do this recursively on the target type. */
762 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
763 int quals = cp_type_quals (t1);
765 if (code1 == POINTER_TYPE)
766 t1 = build_pointer_type (target);
768 t1 = cp_build_reference_type (target, TYPE_REF_IS_RVALUE (t1));
769 t1 = build_type_attribute_variant (t1, attributes);
770 t1 = cp_build_qualified_type (t1, quals);
772 if (TREE_CODE (target) == METHOD_TYPE)
773 t1 = build_ptrmemfunc_type (t1);
782 quals = cp_type_quals (t1);
783 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
784 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
785 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
787 t1 = cp_build_qualified_type (t1, quals);
793 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
794 /* Save space: see if the result is identical to one of the args. */
795 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
796 return build_type_attribute_variant (t1, attributes);
797 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
798 return build_type_attribute_variant (t2, attributes);
799 /* Merge the element types, and have a size if either arg has one. */
800 t1 = build_cplus_array_type
801 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
806 /* Function types: prefer the one that specified arg types.
807 If both do, merge the arg types. Also merge the return types. */
809 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
810 tree p1 = TYPE_ARG_TYPES (t1);
811 tree p2 = TYPE_ARG_TYPES (t2);
814 /* Save space: see if the result is identical to one of the args. */
815 if (valtype == TREE_TYPE (t1) && ! p2)
816 return cp_build_type_attribute_variant (t1, attributes);
817 if (valtype == TREE_TYPE (t2) && ! p1)
818 return cp_build_type_attribute_variant (t2, attributes);
820 /* Simple way if one arg fails to specify argument types. */
821 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
823 rval = build_function_type (valtype, p2);
824 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
825 rval = build_exception_variant (rval, raises);
826 return cp_build_type_attribute_variant (rval, attributes);
828 raises = TYPE_RAISES_EXCEPTIONS (t1);
829 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
831 rval = build_function_type (valtype, p1);
833 rval = build_exception_variant (rval, raises);
834 return cp_build_type_attribute_variant (rval, attributes);
837 rval = build_function_type (valtype, commonparms (p1, p2));
838 t1 = build_exception_variant (rval, raises);
844 /* Get this value the long way, since TYPE_METHOD_BASETYPE
845 is just the main variant of this. */
846 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
847 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
850 /* If this was a member function type, get back to the
851 original type of type member function (i.e., without
852 the class instance variable up front. */
853 t1 = build_function_type (TREE_TYPE (t1),
854 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
855 t2 = build_function_type (TREE_TYPE (t2),
856 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
857 t3 = merge_types (t1, t2);
858 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
859 TYPE_ARG_TYPES (t3));
860 t1 = build_exception_variant (t3, raises);
865 /* There is no need to merge attributes into a TYPENAME_TYPE.
866 When the type is instantiated it will have whatever
867 attributes result from the instantiation. */
873 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
875 else if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
878 return cp_build_type_attribute_variant (t1, attributes);
881 /* Return the ARRAY_TYPE type without its domain. */
884 strip_array_domain (tree type)
887 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
888 if (TYPE_DOMAIN (type) == NULL_TREE)
890 t2 = build_cplus_array_type (TREE_TYPE (type), NULL_TREE);
891 return cp_build_type_attribute_variant (t2, TYPE_ATTRIBUTES (type));
894 /* Wrapper around cp_common_type that is used by c-common.c and other
895 front end optimizations that remove promotions.
897 Return the common type for two arithmetic types T1 and T2 under the
898 usual arithmetic conversions. The default conversions have already
899 been applied, and enumerated types converted to their compatible
903 common_type (tree t1, tree t2)
905 /* If one type is nonsense, use the other */
906 if (t1 == error_mark_node)
908 if (t2 == error_mark_node)
911 return cp_common_type (t1, t2);
914 /* Return the common type of two pointer types T1 and T2. This is the
915 type for the result of most arithmetic operations if the operands
916 have the given two types.
918 We assume that comp_target_types has already been done and returned
919 nonzero; if that isn't so, this may crash. */
922 common_pointer_type (tree t1, tree t2)
924 gcc_assert ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
925 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
926 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)));
928 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
929 CPO_CONVERSION, tf_warning_or_error);
932 /* Compare two exception specifier types for exactness or subsetness, if
933 allowed. Returns false for mismatch, true for match (same, or
936 [except.spec] "If a class X ... objects of class X or any class publicly
937 and unambiguously derived from X. Similarly, if a pointer type Y * ...
938 exceptions of type Y * or that are pointers to any type publicly and
939 unambiguously derived from Y. Otherwise a function only allows exceptions
940 that have the same type ..."
941 This does not mention cv qualifiers and is different to what throw
942 [except.throw] and catch [except.catch] will do. They will ignore the
943 top level cv qualifiers, and allow qualifiers in the pointer to class
946 We implement the letter of the standard. */
949 comp_except_types (tree a, tree b, bool exact)
951 if (same_type_p (a, b))
955 if (cp_type_quals (a) || cp_type_quals (b))
958 if (TREE_CODE (a) == POINTER_TYPE
959 && TREE_CODE (b) == POINTER_TYPE)
963 if (cp_type_quals (a) || cp_type_quals (b))
967 if (TREE_CODE (a) != RECORD_TYPE
968 || TREE_CODE (b) != RECORD_TYPE)
971 if (PUBLICLY_UNIQUELY_DERIVED_P (a, b))
977 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
978 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
979 otherwise it must be exact. Exception lists are unordered, but
980 we've already filtered out duplicates. Most lists will be in order,
981 we should try to make use of that. */
984 comp_except_specs (const_tree t1, const_tree t2, bool exact)
993 if (t1 == NULL_TREE) /* T1 is ... */
994 return t2 == NULL_TREE || !exact;
995 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
996 return t2 != NULL_TREE && !TREE_VALUE (t2);
997 if (t2 == NULL_TREE) /* T2 is ... */
999 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
1002 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
1003 Count how many we find, to determine exactness. For exact matching and
1004 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
1006 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
1008 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
1010 tree a = TREE_VALUE (probe);
1011 tree b = TREE_VALUE (t2);
1013 if (comp_except_types (a, b, exact))
1015 if (probe == base && exact)
1016 base = TREE_CHAIN (probe);
1021 if (probe == NULL_TREE)
1024 return !exact || base == NULL_TREE || length == list_length (t1);
1027 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
1028 [] can match [size]. */
1031 comp_array_types (const_tree t1, const_tree t2, bool allow_redeclaration)
1040 /* The type of the array elements must be the same. */
1041 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1044 d1 = TYPE_DOMAIN (t1);
1045 d2 = TYPE_DOMAIN (t2);
1050 /* If one of the arrays is dimensionless, and the other has a
1051 dimension, they are of different types. However, it is valid to
1059 declarations for an array object can specify
1060 array types that differ by the presence or absence of a major
1061 array bound (_dcl.array_). */
1063 return allow_redeclaration;
1065 /* Check that the dimensions are the same. */
1067 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
1069 max1 = TYPE_MAX_VALUE (d1);
1070 max2 = TYPE_MAX_VALUE (d2);
1071 if (processing_template_decl && !abi_version_at_least (2)
1072 && !value_dependent_expression_p (max1)
1073 && !value_dependent_expression_p (max2))
1075 /* With abi-1 we do not fold non-dependent array bounds, (and
1076 consequently mangle them incorrectly). We must therefore
1077 fold them here, to verify the domains have the same
1083 if (!cp_tree_equal (max1, max2))
1089 /* Compare the relative position of T1 and T2 into their respective
1090 template parameter list.
1091 T1 and T2 must be template parameter types.
1092 Return TRUE if T1 and T2 have the same position, FALSE otherwise. */
1095 comp_template_parms_position (tree t1, tree t2)
1097 gcc_assert (t1 && t2
1098 && TREE_CODE (t1) == TREE_CODE (t2)
1099 && (TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM
1100 || TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM
1101 || TREE_CODE (t1) == TEMPLATE_TYPE_PARM));
1103 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1104 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2)
1105 || (TEMPLATE_TYPE_PARAMETER_PACK (t1)
1106 != TEMPLATE_TYPE_PARAMETER_PACK (t2)))
1112 /* Subroutine of incompatible_dependent_types_p.
1113 Return the template parameter of the dependent type T.
1114 If T is a typedef, return the template parameters of
1115 the _decl_ of the typedef. T must be a dependent type. */
1118 get_template_parms_of_dependent_type (tree t)
1120 tree tinfo = NULL_TREE, tparms = NULL_TREE;
1122 /* First, try the obvious case of getting the
1123 template info from T itself. */
1124 if ((tinfo = get_template_info (t)))
1126 else if (TREE_CODE (t) == TEMPLATE_TYPE_PARM)
1127 return TEMPLATE_TYPE_PARM_SIBLING_PARMS (t);
1128 else if (typedef_variant_p (t)
1129 && !NAMESPACE_SCOPE_P (TYPE_NAME (t)))
1130 tinfo = get_template_info (DECL_CONTEXT (TYPE_NAME (t)));
1131 /* If T is a TYPENAME_TYPE which context is a template type
1132 parameter, get the template parameters from that context. */
1133 else if (TYPE_CONTEXT (t)
1134 && TREE_CODE (TYPE_CONTEXT (t)) == TEMPLATE_TYPE_PARM)
1135 return TEMPLATE_TYPE_PARM_SIBLING_PARMS (TYPE_CONTEXT (t));
1136 else if (TYPE_CONTEXT (t)
1137 && !NAMESPACE_SCOPE_P (t))
1138 tinfo = get_template_info (TYPE_CONTEXT (t));
1141 tparms = DECL_TEMPLATE_PARMS (TI_TEMPLATE (tinfo));
1146 /* Subroutine of structural_comptypes.
1147 Compare the dependent types T1 and T2.
1148 Return TRUE if we are sure they can't be equal, FALSE otherwise.
1149 The whole point of this function is to support cases where either T1 or
1150 T2 is a typedef. In those cases, we need to compare the template parameters
1151 of the _decl_ of the typedef. If those don't match then we know T1
1152 and T2 cannot be equal. */
1155 incompatible_dependent_types_p (tree t1, tree t2)
1157 tree tparms1 = NULL_TREE, tparms2 = NULL_TREE;
1159 if (!uses_template_parms (t1) || !uses_template_parms (t2))
1162 if (TREE_CODE (t1) == TEMPLATE_TYPE_PARM)
1164 /* If T1 and T2 don't have the same relative position in their
1165 template parameters set, they can't be equal. */
1166 if (!comp_template_parms_position (t1, t2))
1170 /* Either T1 or T2 must be a typedef. */
1171 if (!typedef_variant_p (t1) && !typedef_variant_p (t2))
1174 /* So if we reach this point, it means either T1 or T2 is a typedef variant.
1175 Let's compare their template parameters. */
1177 tparms1 = get_template_parms_of_dependent_type (t1);
1178 tparms2 = get_template_parms_of_dependent_type (t2);
1180 /* If T2 is a template type parm and if we could not get the template
1181 parms it belongs to, that means we have not finished parsing the
1182 full set of template parameters of the template declaration it
1183 belongs to yet. If we could get the template parms T1 belongs to,
1184 that mostly means T1 and T2 belongs to templates that are
1185 different and incompatible. */
1186 if (TREE_CODE (t1) == TEMPLATE_TYPE_PARM
1187 && (tparms1 == NULL_TREE || tparms2 == NULL_TREE)
1188 && tparms1 != tparms2)
1191 if (tparms1 == NULL_TREE
1192 || tparms2 == NULL_TREE
1193 || tparms1 == tparms2)
1196 /* And now compare the mighty template parms! */
1197 return !comp_template_parms (tparms1, tparms2);
1200 /* Subroutine in comptypes. */
1203 structural_comptypes (tree t1, tree t2, int strict)
1208 /* Suppress errors caused by previously reported errors. */
1209 if (t1 == error_mark_node || t2 == error_mark_node)
1212 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
1214 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
1215 current instantiation. */
1216 if (TREE_CODE (t1) == TYPENAME_TYPE)
1217 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
1219 if (TREE_CODE (t2) == TYPENAME_TYPE)
1220 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
1222 if (TYPE_PTRMEMFUNC_P (t1))
1223 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
1224 if (TYPE_PTRMEMFUNC_P (t2))
1225 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
1227 /* Different classes of types can't be compatible. */
1228 if (TREE_CODE (t1) != TREE_CODE (t2))
1231 /* Qualifiers must match. For array types, we will check when we
1232 recur on the array element types. */
1233 if (TREE_CODE (t1) != ARRAY_TYPE
1234 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
1236 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
1239 /* Allow for two different type nodes which have essentially the same
1240 definition. Note that we already checked for equality of the type
1241 qualifiers (just above). */
1243 if (TREE_CODE (t1) != ARRAY_TYPE
1244 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
1247 /* If T1 and T2 are dependent typedefs then check upfront that
1248 the template parameters of their typedef DECLs match before
1249 going down checking their subtypes. */
1250 if (incompatible_dependent_types_p (t1, t2))
1253 /* Compare the types. Break out if they could be the same. */
1254 switch (TREE_CODE (t1))
1258 /* All void and bool types are the same. */
1262 case FIXED_POINT_TYPE:
1264 /* With these nodes, we can't determine type equivalence by
1265 looking at what is stored in the nodes themselves, because
1266 two nodes might have different TYPE_MAIN_VARIANTs but still
1267 represent the same type. For example, wchar_t and int could
1268 have the same properties (TYPE_PRECISION, TYPE_MIN_VALUE,
1269 TYPE_MAX_VALUE, etc.), but have different TYPE_MAIN_VARIANTs
1270 and are distinct types. On the other hand, int and the
1273 typedef int INT __attribute((may_alias));
1275 have identical properties, different TYPE_MAIN_VARIANTs, but
1276 represent the same type. The canonical type system keeps
1277 track of equivalence in this case, so we fall back on it. */
1278 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1280 case TEMPLATE_TEMPLATE_PARM:
1281 case BOUND_TEMPLATE_TEMPLATE_PARM:
1282 if (!comp_template_parms_position (t1, t2))
1284 if (!comp_template_parms
1285 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1286 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1288 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1290 /* Don't check inheritance. */
1291 strict = COMPARE_STRICT;
1296 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1297 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1298 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1299 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1302 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1304 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1310 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1311 strict & ~COMPARE_REDECLARATION))
1313 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1317 case REFERENCE_TYPE:
1318 if (TYPE_REF_IS_RVALUE (t1) != TYPE_REF_IS_RVALUE (t2))
1320 /* fall through to checks for pointer types */
1323 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1324 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)
1325 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1331 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1333 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1338 /* Target types must match incl. qualifiers. */
1339 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1343 case TEMPLATE_TYPE_PARM:
1344 /* If incompatible_dependent_types_p called earlier didn't decide
1345 T1 and T2 were different, they might be equal. */
1349 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1350 TYPENAME_TYPE_FULLNAME (t2)))
1352 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1356 case UNBOUND_CLASS_TEMPLATE:
1357 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1359 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1364 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1369 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1370 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1374 case TYPE_PACK_EXPANSION:
1375 return same_type_p (PACK_EXPANSION_PATTERN (t1),
1376 PACK_EXPANSION_PATTERN (t2));
1379 if (DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t1)
1380 != DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t2)
1381 || (DECLTYPE_FOR_LAMBDA_CAPTURE (t1)
1382 != DECLTYPE_FOR_LAMBDA_CAPTURE (t2))
1383 || (DECLTYPE_FOR_LAMBDA_RETURN (t1)
1384 != DECLTYPE_FOR_LAMBDA_RETURN (t2))
1385 || !cp_tree_equal (DECLTYPE_TYPE_EXPR (t1),
1386 DECLTYPE_TYPE_EXPR (t2)))
1394 /* If we get here, we know that from a target independent POV the
1395 types are the same. Make sure the target attributes are also
1397 return targetm.comp_type_attributes (t1, t2);
1400 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
1401 is a bitwise-or of the COMPARE_* flags. */
1404 comptypes (tree t1, tree t2, int strict)
1406 if (strict == COMPARE_STRICT)
1411 if (t1 == error_mark_node || t2 == error_mark_node)
1414 if (TYPE_STRUCTURAL_EQUALITY_P (t1) || TYPE_STRUCTURAL_EQUALITY_P (t2))
1415 /* At least one of the types requires structural equality, so
1416 perform a deep check. */
1417 return structural_comptypes (t1, t2, strict);
1419 #ifdef ENABLE_CHECKING
1420 if (USE_CANONICAL_TYPES)
1422 bool result = structural_comptypes (t1, t2, strict);
1424 if (result && TYPE_CANONICAL (t1) != TYPE_CANONICAL (t2))
1425 /* The two types are structurally equivalent, but their
1426 canonical types were different. This is a failure of the
1427 canonical type propagation code.*/
1429 ("canonical types differ for identical types %T and %T",
1431 else if (!result && TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2))
1432 /* Two types are structurally different, but the canonical
1433 types are the same. This means we were over-eager in
1434 assigning canonical types. */
1436 ("same canonical type node for different types %T and %T",
1442 if (USE_CANONICAL_TYPES)
1443 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1446 return structural_comptypes (t1, t2, strict);
1448 else if (strict == COMPARE_STRUCTURAL)
1449 return structural_comptypes (t1, t2, COMPARE_STRICT);
1451 return structural_comptypes (t1, t2, strict);
1454 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1457 at_least_as_qualified_p (const_tree type1, const_tree type2)
1459 int q1 = cp_type_quals (type1);
1460 int q2 = cp_type_quals (type2);
1462 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1463 return (q1 & q2) == q2;
1466 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1467 more cv-qualified that TYPE1, and 0 otherwise. */
1470 comp_cv_qualification (const_tree type1, const_tree type2)
1472 int q1 = cp_type_quals (type1);
1473 int q2 = cp_type_quals (type2);
1478 if ((q1 & q2) == q2)
1480 else if ((q1 & q2) == q1)
1486 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1487 subset of the cv-qualification signature of TYPE2, and the types
1488 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1491 comp_cv_qual_signature (tree type1, tree type2)
1493 if (comp_ptr_ttypes_real (type2, type1, -1))
1495 else if (comp_ptr_ttypes_real (type1, type2, -1))
1501 /* Subroutines of `comptypes'. */
1503 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1504 equivalent in the sense that functions with those parameter types
1505 can have equivalent types. The two lists must be equivalent,
1506 element by element. */
1509 compparms (const_tree parms1, const_tree parms2)
1513 /* An unspecified parmlist matches any specified parmlist
1514 whose argument types don't need default promotions. */
1516 for (t1 = parms1, t2 = parms2;
1518 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1520 /* If one parmlist is shorter than the other,
1521 they fail to match. */
1524 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1531 /* Process a sizeof or alignof expression where the operand is a
1535 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1540 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1541 if (type == error_mark_node)
1542 return error_mark_node;
1544 type = non_reference (type);
1545 if (TREE_CODE (type) == METHOD_TYPE)
1548 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
1549 "invalid application of %qs to a member function",
1550 operator_name_info[(int) op].name);
1551 value = size_one_node;
1554 dependent_p = dependent_type_p (type);
1556 complete_type (type);
1558 /* VLA types will have a non-constant size. In the body of an
1559 uninstantiated template, we don't need to try to compute the
1560 value, because the sizeof expression is not an integral
1561 constant expression in that case. And, if we do try to
1562 compute the value, we'll likely end up with SAVE_EXPRs, which
1563 the template substitution machinery does not expect to see. */
1564 || (processing_template_decl
1565 && COMPLETE_TYPE_P (type)
1566 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST))
1568 value = build_min (op, size_type_node, type);
1569 TREE_READONLY (value) = 1;
1573 return c_sizeof_or_alignof_type (input_location, complete_type (type),
1578 /* Return the size of the type, without producing any warnings for
1579 types whose size cannot be taken. This routine should be used only
1580 in some other routine that has already produced a diagnostic about
1581 using the size of such a type. */
1583 cxx_sizeof_nowarn (tree type)
1585 if (TREE_CODE (type) == FUNCTION_TYPE
1586 || TREE_CODE (type) == VOID_TYPE
1587 || TREE_CODE (type) == ERROR_MARK)
1588 return size_one_node;
1589 else if (!COMPLETE_TYPE_P (type))
1590 return size_zero_node;
1592 return cxx_sizeof_or_alignof_type (type, SIZEOF_EXPR, false);
1595 /* Process a sizeof expression where the operand is an expression. */
1598 cxx_sizeof_expr (tree e, tsubst_flags_t complain)
1600 if (e == error_mark_node)
1601 return error_mark_node;
1603 if (processing_template_decl)
1605 e = build_min (SIZEOF_EXPR, size_type_node, e);
1606 TREE_SIDE_EFFECTS (e) = 0;
1607 TREE_READONLY (e) = 1;
1612 /* To get the size of a static data member declared as an array of
1613 unknown bound, we need to instantiate it. */
1614 if (TREE_CODE (e) == VAR_DECL
1615 && VAR_HAD_UNKNOWN_BOUND (e)
1616 && DECL_TEMPLATE_INSTANTIATION (e))
1617 instantiate_decl (e, /*defer_ok*/true, /*expl_inst_mem*/false);
1619 if (TREE_CODE (e) == COMPONENT_REF
1620 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1621 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1623 if (complain & tf_error)
1624 error ("invalid application of %<sizeof%> to a bit-field");
1626 return error_mark_node;
1629 else if (is_overloaded_fn (e))
1631 if (complain & tf_error)
1632 permerror (input_location, "ISO C++ forbids applying %<sizeof%> to an expression of "
1635 return error_mark_node;
1638 else if (type_unknown_p (e))
1640 if (complain & tf_error)
1641 cxx_incomplete_type_error (e, TREE_TYPE (e));
1643 return error_mark_node;
1649 return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, complain & tf_error);
1652 /* Implement the __alignof keyword: Return the minimum required
1653 alignment of E, measured in bytes. For VAR_DECL's and
1654 FIELD_DECL's return DECL_ALIGN (which can be set from an
1655 "aligned" __attribute__ specification). */
1658 cxx_alignof_expr (tree e, tsubst_flags_t complain)
1662 if (e == error_mark_node)
1663 return error_mark_node;
1665 if (processing_template_decl)
1667 e = build_min (ALIGNOF_EXPR, size_type_node, e);
1668 TREE_SIDE_EFFECTS (e) = 0;
1669 TREE_READONLY (e) = 1;
1674 if (TREE_CODE (e) == VAR_DECL)
1675 t = size_int (DECL_ALIGN_UNIT (e));
1676 else if (TREE_CODE (e) == COMPONENT_REF
1677 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1678 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1680 if (complain & tf_error)
1681 error ("invalid application of %<__alignof%> to a bit-field");
1683 return error_mark_node;
1686 else if (TREE_CODE (e) == COMPONENT_REF
1687 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL)
1688 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1)));
1689 else if (is_overloaded_fn (e))
1691 if (complain & tf_error)
1692 permerror (input_location, "ISO C++ forbids applying %<__alignof%> to an expression of "
1695 return error_mark_node;
1696 if (TREE_CODE (e) == FUNCTION_DECL)
1697 t = size_int (DECL_ALIGN_UNIT (e));
1701 else if (type_unknown_p (e))
1703 if (complain & tf_error)
1704 cxx_incomplete_type_error (e, TREE_TYPE (e));
1706 return error_mark_node;
1710 return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR,
1711 complain & tf_error);
1713 return fold_convert (size_type_node, t);
1716 /* Process a sizeof or alignof expression E with code OP where the operand
1717 is an expression. */
1720 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op, bool complain)
1722 if (op == SIZEOF_EXPR)
1723 return cxx_sizeof_expr (e, complain? tf_warning_or_error : tf_none);
1725 return cxx_alignof_expr (e, complain? tf_warning_or_error : tf_none);
1728 /* EXPR is being used in a context that is not a function call.
1733 The expression can be used only as the left-hand operand of a
1734 member function call.
1736 [expr.mptr.operator]
1738 If the result of .* or ->* is a function, then that result can be
1739 used only as the operand for the function call operator ().
1741 by issuing an error message if appropriate. Returns true iff EXPR
1742 violates these rules. */
1745 invalid_nonstatic_memfn_p (const_tree expr, tsubst_flags_t complain)
1747 if (expr && DECL_NONSTATIC_MEMBER_FUNCTION_P (expr))
1749 if (complain & tf_error)
1750 error ("invalid use of non-static member function");
1756 /* If EXP is a reference to a bitfield, and the type of EXP does not
1757 match the declared type of the bitfield, return the declared type
1758 of the bitfield. Otherwise, return NULL_TREE. */
1761 is_bitfield_expr_with_lowered_type (const_tree exp)
1763 switch (TREE_CODE (exp))
1766 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)
1767 ? TREE_OPERAND (exp, 1)
1768 : TREE_OPERAND (exp, 0)))
1770 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2));
1773 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1));
1777 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1783 field = TREE_OPERAND (exp, 1);
1784 if (TREE_CODE (field) != FIELD_DECL || !DECL_BIT_FIELD_TYPE (field))
1786 if (same_type_ignoring_top_level_qualifiers_p
1787 (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field)))
1789 return DECL_BIT_FIELD_TYPE (field);
1793 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (exp, 0)))
1794 == TYPE_MAIN_VARIANT (TREE_TYPE (exp)))
1795 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1803 /* Like is_bitfield_with_lowered_type, except that if EXP is not a
1804 bitfield with a lowered type, the type of EXP is returned, rather
1808 unlowered_expr_type (const_tree exp)
1812 type = is_bitfield_expr_with_lowered_type (exp);
1814 type = TREE_TYPE (exp);
1819 /* Perform the conversions in [expr] that apply when an lvalue appears
1820 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1821 function-to-pointer conversions. In addition, manifest constants
1822 are replaced by their values, and bitfield references are converted
1823 to their declared types.
1825 Although the returned value is being used as an rvalue, this
1826 function does not wrap the returned expression in a
1827 NON_LVALUE_EXPR; the caller is expected to be mindful of the fact
1828 that the return value is no longer an lvalue. */
1831 decay_conversion (tree exp)
1834 enum tree_code code;
1836 type = TREE_TYPE (exp);
1837 if (type == error_mark_node)
1838 return error_mark_node;
1840 exp = resolve_nondeduced_context (exp);
1841 if (type_unknown_p (exp))
1843 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1844 return error_mark_node;
1847 exp = decl_constant_value (exp);
1848 if (error_operand_p (exp))
1849 return error_mark_node;
1851 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1852 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1853 code = TREE_CODE (type);
1854 if (code == VOID_TYPE)
1856 error ("void value not ignored as it ought to be");
1857 return error_mark_node;
1859 if (invalid_nonstatic_memfn_p (exp, tf_warning_or_error))
1860 return error_mark_node;
1861 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1862 return cp_build_unary_op (ADDR_EXPR, exp, 0, tf_warning_or_error);
1863 if (code == ARRAY_TYPE)
1868 if (TREE_CODE (exp) == INDIRECT_REF)
1869 return build_nop (build_pointer_type (TREE_TYPE (type)),
1870 TREE_OPERAND (exp, 0));
1872 if (TREE_CODE (exp) == COMPOUND_EXPR)
1874 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1875 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1876 TREE_OPERAND (exp, 0), op1);
1880 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1882 error ("invalid use of non-lvalue array");
1883 return error_mark_node;
1886 ptrtype = build_pointer_type (TREE_TYPE (type));
1888 if (TREE_CODE (exp) == VAR_DECL)
1890 if (!cxx_mark_addressable (exp))
1891 return error_mark_node;
1892 adr = build_nop (ptrtype, build_address (exp));
1895 /* This way is better for a COMPONENT_REF since it can
1896 simplify the offset for a component. */
1897 adr = cp_build_unary_op (ADDR_EXPR, exp, 1, tf_warning_or_error);
1898 return cp_convert (ptrtype, adr);
1901 /* If a bitfield is used in a context where integral promotion
1902 applies, then the caller is expected to have used
1903 default_conversion. That function promotes bitfields correctly
1904 before calling this function. At this point, if we have a
1905 bitfield referenced, we may assume that is not subject to
1906 promotion, and that, therefore, the type of the resulting rvalue
1907 is the declared type of the bitfield. */
1908 exp = convert_bitfield_to_declared_type (exp);
1910 /* We do not call rvalue() here because we do not want to wrap EXP
1911 in a NON_LVALUE_EXPR. */
1915 Non-class rvalues always have cv-unqualified types. */
1916 type = TREE_TYPE (exp);
1917 if (!CLASS_TYPE_P (type) && cv_qualified_p (type))
1918 exp = build_nop (cv_unqualified (type), exp);
1923 /* Perform preparatory conversions, as part of the "usual arithmetic
1924 conversions". In particular, as per [expr]:
1926 Whenever an lvalue expression appears as an operand of an
1927 operator that expects the rvalue for that operand, the
1928 lvalue-to-rvalue, array-to-pointer, or function-to-pointer
1929 standard conversions are applied to convert the expression to an
1932 In addition, we perform integral promotions here, as those are
1933 applied to both operands to a binary operator before determining
1934 what additional conversions should apply. */
1937 default_conversion (tree exp)
1939 /* Check for target-specific promotions. */
1940 tree promoted_type = targetm.promoted_type (TREE_TYPE (exp));
1942 exp = cp_convert (promoted_type, exp);
1943 /* Perform the integral promotions first so that bitfield
1944 expressions (which may promote to "int", even if the bitfield is
1945 declared "unsigned") are promoted correctly. */
1946 else if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1947 exp = perform_integral_promotions (exp);
1948 /* Perform the other conversions. */
1949 exp = decay_conversion (exp);
1954 /* EXPR is an expression with an integral or enumeration type.
1955 Perform the integral promotions in [conv.prom], and return the
1959 perform_integral_promotions (tree expr)
1966 If the bitfield has an enumerated type, it is treated as any
1967 other value of that type for promotion purposes. */
1968 type = is_bitfield_expr_with_lowered_type (expr);
1969 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
1970 type = TREE_TYPE (expr);
1971 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1972 promoted_type = type_promotes_to (type);
1973 if (type != promoted_type)
1974 expr = cp_convert (promoted_type, expr);
1978 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1979 decay_conversion to one. */
1982 string_conv_p (const_tree totype, const_tree exp, int warn)
1986 if (TREE_CODE (totype) != POINTER_TYPE)
1989 t = TREE_TYPE (totype);
1990 if (!same_type_p (t, char_type_node)
1991 && !same_type_p (t, char16_type_node)
1992 && !same_type_p (t, char32_type_node)
1993 && !same_type_p (t, wchar_type_node))
1996 if (TREE_CODE (exp) == STRING_CST)
1998 /* Make sure that we don't try to convert between char and wide chars. */
1999 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
2004 /* Is this a string constant which has decayed to 'const char *'? */
2005 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
2006 if (!same_type_p (TREE_TYPE (exp), t))
2009 if (TREE_CODE (exp) != ADDR_EXPR
2010 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
2014 /* This warning is not very useful, as it complains about printf. */
2016 warning (OPT_Wwrite_strings,
2017 "deprecated conversion from string constant to %qT",
2023 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
2024 can, for example, use as an lvalue. This code used to be in
2025 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
2026 expressions, where we're dealing with aggregates. But now it's again only
2027 called from unary_complex_lvalue. The case (in particular) that led to
2028 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
2032 rationalize_conditional_expr (enum tree_code code, tree t,
2033 tsubst_flags_t complain)
2035 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
2036 the first operand is always the one to be used if both operands
2037 are equal, so we know what conditional expression this used to be. */
2038 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
2040 tree op0 = TREE_OPERAND (t, 0);
2041 tree op1 = TREE_OPERAND (t, 1);
2043 /* The following code is incorrect if either operand side-effects. */
2044 gcc_assert (!TREE_SIDE_EFFECTS (op0)
2045 && !TREE_SIDE_EFFECTS (op1));
2047 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
2048 ? LE_EXPR : GE_EXPR),
2049 op0, TREE_CODE (op0),
2050 op1, TREE_CODE (op1),
2051 /*overloaded_p=*/NULL,
2053 cp_build_unary_op (code, op0, 0, complain),
2054 cp_build_unary_op (code, op1, 0, complain),
2059 build_conditional_expr (TREE_OPERAND (t, 0),
2060 cp_build_unary_op (code, TREE_OPERAND (t, 1), 0,
2062 cp_build_unary_op (code, TREE_OPERAND (t, 2), 0,
2067 /* Given the TYPE of an anonymous union field inside T, return the
2068 FIELD_DECL for the field. If not found return NULL_TREE. Because
2069 anonymous unions can nest, we must also search all anonymous unions
2070 that are directly reachable. */
2073 lookup_anon_field (tree t, tree type)
2077 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
2079 if (TREE_STATIC (field))
2081 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
2084 /* If we find it directly, return the field. */
2085 if (DECL_NAME (field) == NULL_TREE
2086 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
2091 /* Otherwise, it could be nested, search harder. */
2092 if (DECL_NAME (field) == NULL_TREE
2093 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
2095 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
2103 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
2104 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
2105 non-NULL, it indicates the path to the base used to name MEMBER.
2106 If PRESERVE_REFERENCE is true, the expression returned will have
2107 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
2108 returned will have the type referred to by the reference.
2110 This function does not perform access control; that is either done
2111 earlier by the parser when the name of MEMBER is resolved to MEMBER
2112 itself, or later when overload resolution selects one of the
2113 functions indicated by MEMBER. */
2116 build_class_member_access_expr (tree object, tree member,
2117 tree access_path, bool preserve_reference,
2118 tsubst_flags_t complain)
2122 tree result = NULL_TREE;
2124 if (error_operand_p (object) || error_operand_p (member))
2125 return error_mark_node;
2127 gcc_assert (DECL_P (member) || BASELINK_P (member));
2131 The type of the first expression shall be "class object" (of a
2133 object_type = TREE_TYPE (object);
2134 if (!currently_open_class (object_type)
2135 && !complete_type_or_else (object_type, object))
2136 return error_mark_node;
2137 if (!CLASS_TYPE_P (object_type))
2139 if (complain & tf_error)
2140 error ("request for member %qD in %qE, which is of non-class type %qT",
2141 member, object, object_type);
2142 return error_mark_node;
2145 /* The standard does not seem to actually say that MEMBER must be a
2146 member of OBJECT_TYPE. However, that is clearly what is
2148 if (DECL_P (member))
2150 member_scope = DECL_CLASS_CONTEXT (member);
2152 if (TREE_DEPRECATED (member))
2153 warn_deprecated_use (member, NULL_TREE);
2156 member_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (member));
2157 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
2158 presently be the anonymous union. Go outwards until we find a
2159 type related to OBJECT_TYPE. */
2160 while (ANON_AGGR_TYPE_P (member_scope)
2161 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
2163 member_scope = TYPE_CONTEXT (member_scope);
2164 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
2166 if (complain & tf_error)
2168 if (TREE_CODE (member) == FIELD_DECL)
2169 error ("invalid use of nonstatic data member %qE", member);
2171 error ("%qD is not a member of %qT", member, object_type);
2173 return error_mark_node;
2176 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
2177 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
2178 in the front end; only _DECLs and _REFs are lvalues in the back end. */
2180 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
2182 object = cp_build_indirect_ref (temp, RO_NULL, complain);
2185 /* In [expr.ref], there is an explicit list of the valid choices for
2186 MEMBER. We check for each of those cases here. */
2187 if (TREE_CODE (member) == VAR_DECL)
2189 /* A static data member. */
2191 /* If OBJECT has side-effects, they are supposed to occur. */
2192 if (TREE_SIDE_EFFECTS (object))
2193 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
2195 else if (TREE_CODE (member) == FIELD_DECL)
2197 /* A non-static data member. */
2202 null_object_p = (TREE_CODE (object) == INDIRECT_REF
2203 && integer_zerop (TREE_OPERAND (object, 0)));
2205 /* Convert OBJECT to the type of MEMBER. */
2206 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
2207 TYPE_MAIN_VARIANT (member_scope)))
2212 binfo = lookup_base (access_path ? access_path : object_type,
2213 member_scope, ba_unique, &kind);
2214 if (binfo == error_mark_node)
2215 return error_mark_node;
2217 /* It is invalid to try to get to a virtual base of a
2218 NULL object. The most common cause is invalid use of
2220 if (null_object_p && kind == bk_via_virtual)
2222 if (complain & tf_error)
2224 error ("invalid access to non-static data member %qD of "
2227 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
2229 return error_mark_node;
2232 /* Convert to the base. */
2233 object = build_base_path (PLUS_EXPR, object, binfo,
2235 /* If we found the base successfully then we should be able
2236 to convert to it successfully. */
2237 gcc_assert (object != error_mark_node);
2240 /* Complain about other invalid uses of offsetof, even though they will
2241 give the right answer. Note that we complain whether or not they
2242 actually used the offsetof macro, since there's no way to know at this
2243 point. So we just give a warning, instead of a pedwarn. */
2244 /* Do not produce this warning for base class field references, because
2245 we know for a fact that didn't come from offsetof. This does occur
2246 in various testsuite cases where a null object is passed where a
2247 vtable access is required. */
2248 if (null_object_p && warn_invalid_offsetof
2249 && CLASSTYPE_NON_STD_LAYOUT (object_type)
2250 && !DECL_FIELD_IS_BASE (member)
2251 && cp_unevaluated_operand == 0
2252 && (complain & tf_warning))
2254 warning (OPT_Winvalid_offsetof,
2255 "invalid access to non-static data member %qD "
2256 " of NULL object", member);
2257 warning (OPT_Winvalid_offsetof,
2258 "(perhaps the %<offsetof%> macro was used incorrectly)");
2261 /* If MEMBER is from an anonymous aggregate, we have converted
2262 OBJECT so that it refers to the class containing the
2263 anonymous union. Generate a reference to the anonymous union
2264 itself, and recur to find MEMBER. */
2265 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
2266 /* When this code is called from build_field_call, the
2267 object already has the type of the anonymous union.
2268 That is because the COMPONENT_REF was already
2269 constructed, and was then disassembled before calling
2270 build_field_call. After the function-call code is
2271 cleaned up, this waste can be eliminated. */
2272 && (!same_type_ignoring_top_level_qualifiers_p
2273 (TREE_TYPE (object), DECL_CONTEXT (member))))
2275 tree anonymous_union;
2277 anonymous_union = lookup_anon_field (TREE_TYPE (object),
2278 DECL_CONTEXT (member));
2279 object = build_class_member_access_expr (object,
2281 /*access_path=*/NULL_TREE,
2286 /* Compute the type of the field, as described in [expr.ref]. */
2287 type_quals = TYPE_UNQUALIFIED;
2288 member_type = TREE_TYPE (member);
2289 if (TREE_CODE (member_type) != REFERENCE_TYPE)
2291 type_quals = (cp_type_quals (member_type)
2292 | cp_type_quals (object_type));
2294 /* A field is const (volatile) if the enclosing object, or the
2295 field itself, is const (volatile). But, a mutable field is
2296 not const, even within a const object. */
2297 if (DECL_MUTABLE_P (member))
2298 type_quals &= ~TYPE_QUAL_CONST;
2299 member_type = cp_build_qualified_type (member_type, type_quals);
2302 result = build3 (COMPONENT_REF, member_type, object, member,
2304 result = fold_if_not_in_template (result);
2306 /* Mark the expression const or volatile, as appropriate. Even
2307 though we've dealt with the type above, we still have to mark the
2308 expression itself. */
2309 if (type_quals & TYPE_QUAL_CONST)
2310 TREE_READONLY (result) = 1;
2311 if (type_quals & TYPE_QUAL_VOLATILE)
2312 TREE_THIS_VOLATILE (result) = 1;
2314 else if (BASELINK_P (member))
2316 /* The member is a (possibly overloaded) member function. */
2320 /* If the MEMBER is exactly one static member function, then we
2321 know the type of the expression. Otherwise, we must wait
2322 until overload resolution has been performed. */
2323 functions = BASELINK_FUNCTIONS (member);
2324 if (TREE_CODE (functions) == FUNCTION_DECL
2325 && DECL_STATIC_FUNCTION_P (functions))
2326 type = TREE_TYPE (functions);
2328 type = unknown_type_node;
2329 /* Note that we do not convert OBJECT to the BASELINK_BINFO
2330 base. That will happen when the function is called. */
2331 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
2333 else if (TREE_CODE (member) == CONST_DECL)
2335 /* The member is an enumerator. */
2337 /* If OBJECT has side-effects, they are supposed to occur. */
2338 if (TREE_SIDE_EFFECTS (object))
2339 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2344 if (complain & tf_error)
2345 error ("invalid use of %qD", member);
2346 return error_mark_node;
2349 if (!preserve_reference)
2352 If E2 is declared to have type "reference to T", then ... the
2353 type of E1.E2 is T. */
2354 result = convert_from_reference (result);
2359 /* Return the destructor denoted by OBJECT.SCOPE::DTOR_NAME, or, if
2360 SCOPE is NULL, by OBJECT.DTOR_NAME, where DTOR_NAME is ~type. */
2363 lookup_destructor (tree object, tree scope, tree dtor_name)
2365 tree object_type = TREE_TYPE (object);
2366 tree dtor_type = TREE_OPERAND (dtor_name, 0);
2369 if (scope && !check_dtor_name (scope, dtor_type))
2371 error ("qualified type %qT does not match destructor name ~%qT",
2373 return error_mark_node;
2375 if (TREE_CODE (dtor_type) == IDENTIFIER_NODE)
2377 /* In a template, names we can't find a match for are still accepted
2378 destructor names, and we check them here. */
2379 if (check_dtor_name (object_type, dtor_type))
2380 dtor_type = object_type;
2383 error ("object type %qT does not match destructor name ~%qT",
2384 object_type, dtor_type);
2385 return error_mark_node;
2389 else if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
2391 error ("the type being destroyed is %qT, but the destructor refers to %qT",
2392 TYPE_MAIN_VARIANT (object_type), dtor_type);
2393 return error_mark_node;
2395 expr = lookup_member (dtor_type, complete_dtor_identifier,
2396 /*protect=*/1, /*want_type=*/false);
2397 expr = (adjust_result_of_qualified_name_lookup
2398 (expr, dtor_type, object_type));
2402 /* An expression of the form "A::template B" has been resolved to
2403 DECL. Issue a diagnostic if B is not a template or template
2407 check_template_keyword (tree decl)
2409 /* The standard says:
2413 If a name prefixed by the keyword template is not a member
2414 template, the program is ill-formed.
2416 DR 228 removed the restriction that the template be a member
2419 DR 96, if accepted would add the further restriction that explicit
2420 template arguments must be provided if the template keyword is
2421 used, but, as of 2005-10-16, that DR is still in "drafting". If
2422 this DR is accepted, then the semantic checks here can be
2423 simplified, as the entity named must in fact be a template
2424 specialization, rather than, as at present, a set of overloaded
2425 functions containing at least one template function. */
2426 if (TREE_CODE (decl) != TEMPLATE_DECL
2427 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
2429 if (!is_overloaded_fn (decl))
2430 permerror (input_location, "%qD is not a template", decl);
2435 if (BASELINK_P (fns))
2436 fns = BASELINK_FUNCTIONS (fns);
2439 tree fn = OVL_CURRENT (fns);
2440 if (TREE_CODE (fn) == TEMPLATE_DECL
2441 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2443 if (TREE_CODE (fn) == FUNCTION_DECL
2444 && DECL_USE_TEMPLATE (fn)
2445 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
2447 fns = OVL_NEXT (fns);
2450 permerror (input_location, "%qD is not a template", decl);
2455 /* This function is called by the parser to process a class member
2456 access expression of the form OBJECT.NAME. NAME is a node used by
2457 the parser to represent a name; it is not yet a DECL. It may,
2458 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2459 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2460 there is no reason to do the lookup twice, so the parser keeps the
2461 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2462 be a template via the use of the "A::template B" syntax. */
2465 finish_class_member_access_expr (tree object, tree name, bool template_p,
2466 tsubst_flags_t complain)
2471 tree access_path = NULL_TREE;
2472 tree orig_object = object;
2473 tree orig_name = name;
2475 if (object == error_mark_node || name == error_mark_node)
2476 return error_mark_node;
2478 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2479 if (!objc_is_public (object, name))
2480 return error_mark_node;
2482 object_type = TREE_TYPE (object);
2484 if (processing_template_decl)
2486 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2487 dependent_type_p (object_type)
2488 /* If NAME is just an IDENTIFIER_NODE, then the expression
2490 || TREE_CODE (object) == IDENTIFIER_NODE
2491 /* If NAME is "f<args>", where either 'f' or 'args' is
2492 dependent, then the expression is dependent. */
2493 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2494 && dependent_template_id_p (TREE_OPERAND (name, 0),
2495 TREE_OPERAND (name, 1)))
2496 /* If NAME is "T::X" where "T" is dependent, then the
2497 expression is dependent. */
2498 || (TREE_CODE (name) == SCOPE_REF
2499 && TYPE_P (TREE_OPERAND (name, 0))
2500 && dependent_type_p (TREE_OPERAND (name, 0))))
2501 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2502 object = build_non_dependent_expr (object);
2507 The type of the first expression shall be "class object" (of a
2509 if (!currently_open_class (object_type)
2510 && !complete_type_or_else (object_type, object))
2511 return error_mark_node;
2512 if (!CLASS_TYPE_P (object_type))
2514 if (complain & tf_error)
2515 error ("request for member %qD in %qE, which is of non-class type %qT",
2516 name, object, object_type);
2517 return error_mark_node;
2520 if (BASELINK_P (name))
2521 /* A member function that has already been looked up. */
2525 bool is_template_id = false;
2526 tree template_args = NULL_TREE;
2529 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2531 is_template_id = true;
2532 template_args = TREE_OPERAND (name, 1);
2533 name = TREE_OPERAND (name, 0);
2535 if (TREE_CODE (name) == OVERLOAD)
2536 name = DECL_NAME (get_first_fn (name));
2537 else if (DECL_P (name))
2538 name = DECL_NAME (name);
2541 if (TREE_CODE (name) == SCOPE_REF)
2543 /* A qualified name. The qualifying class or namespace `S'
2544 has already been looked up; it is either a TYPE or a
2546 scope = TREE_OPERAND (name, 0);
2547 name = TREE_OPERAND (name, 1);
2549 /* If SCOPE is a namespace, then the qualified name does not
2550 name a member of OBJECT_TYPE. */
2551 if (TREE_CODE (scope) == NAMESPACE_DECL)
2553 if (complain & tf_error)
2554 error ("%<%D::%D%> is not a member of %qT",
2555 scope, name, object_type);
2556 return error_mark_node;
2559 gcc_assert (CLASS_TYPE_P (scope));
2560 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2561 || TREE_CODE (name) == BIT_NOT_EXPR);
2563 if (constructor_name_p (name, scope))
2565 if (complain & tf_error)
2566 error ("cannot call constructor %<%T::%D%> directly",
2568 return error_mark_node;
2571 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2572 access_path = lookup_base (object_type, scope, ba_check, NULL);
2573 if (access_path == error_mark_node)
2574 return error_mark_node;
2577 if (complain & tf_error)
2578 error ("%qT is not a base of %qT", scope, object_type);
2579 return error_mark_node;
2585 access_path = object_type;
2588 if (TREE_CODE (name) == BIT_NOT_EXPR)
2589 member = lookup_destructor (object, scope, name);
2592 /* Look up the member. */
2593 member = lookup_member (access_path, name, /*protect=*/1,
2594 /*want_type=*/false);
2595 if (member == NULL_TREE)
2597 if (complain & tf_error)
2598 error ("%qD has no member named %qE", object_type, name);
2599 return error_mark_node;
2601 if (member == error_mark_node)
2602 return error_mark_node;
2607 tree templ = member;
2609 if (BASELINK_P (templ))
2610 templ = lookup_template_function (templ, template_args);
2613 if (complain & tf_error)
2614 error ("%qD is not a member template function", name);
2615 return error_mark_node;
2620 if (TREE_DEPRECATED (member))
2621 warn_deprecated_use (member, NULL_TREE);
2624 check_template_keyword (member);
2626 expr = build_class_member_access_expr (object, member, access_path,
2627 /*preserve_reference=*/false,
2629 if (processing_template_decl && expr != error_mark_node)
2631 if (BASELINK_P (member))
2633 if (TREE_CODE (orig_name) == SCOPE_REF)
2634 BASELINK_QUALIFIED_P (member) = 1;
2637 return build_min_non_dep (COMPONENT_REF, expr,
2638 orig_object, orig_name,
2645 /* Return an expression for the MEMBER_NAME field in the internal
2646 representation of PTRMEM, a pointer-to-member function. (Each
2647 pointer-to-member function type gets its own RECORD_TYPE so it is
2648 more convenient to access the fields by name than by FIELD_DECL.)
2649 This routine converts the NAME to a FIELD_DECL and then creates the
2650 node for the complete expression. */
2653 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2659 /* This code is a stripped down version of
2660 build_class_member_access_expr. It does not work to use that
2661 routine directly because it expects the object to be of class
2663 ptrmem_type = TREE_TYPE (ptrmem);
2664 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2665 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2666 /*want_type=*/false);
2667 member_type = cp_build_qualified_type (TREE_TYPE (member),
2668 cp_type_quals (ptrmem_type));
2669 return fold_build3_loc (input_location,
2670 COMPONENT_REF, member_type,
2671 ptrmem, member, NULL_TREE);
2674 /* Given an expression PTR for a pointer, return an expression
2675 for the value pointed to.
2676 ERRORSTRING is the name of the operator to appear in error messages.
2678 This function may need to overload OPERATOR_FNNAME.
2679 Must also handle REFERENCE_TYPEs for C++. */
2682 build_x_indirect_ref (tree expr, ref_operator errorstring,
2683 tsubst_flags_t complain)
2685 tree orig_expr = expr;
2688 if (processing_template_decl)
2690 /* Retain the type if we know the operand is a pointer so that
2691 describable_type doesn't make auto deduction break. */
2692 if (TREE_TYPE (expr) && POINTER_TYPE_P (TREE_TYPE (expr)))
2693 return build_min (INDIRECT_REF, TREE_TYPE (TREE_TYPE (expr)), expr);
2694 if (type_dependent_expression_p (expr))
2695 return build_min_nt (INDIRECT_REF, expr);
2696 expr = build_non_dependent_expr (expr);
2699 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2700 NULL_TREE, /*overloaded_p=*/NULL, complain);
2702 rval = cp_build_indirect_ref (expr, errorstring, complain);
2704 if (processing_template_decl && rval != error_mark_node)
2705 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2710 /* Helper function called from c-common. */
2712 build_indirect_ref (location_t loc __attribute__ ((__unused__)),
2713 tree ptr, ref_operator errorstring)
2715 return cp_build_indirect_ref (ptr, errorstring, tf_warning_or_error);
2719 cp_build_indirect_ref (tree ptr, ref_operator errorstring,
2720 tsubst_flags_t complain)
2724 if (ptr == error_mark_node)
2725 return error_mark_node;
2727 if (ptr == current_class_ptr)
2728 return current_class_ref;
2730 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2731 ? ptr : decay_conversion (ptr));
2732 type = TREE_TYPE (pointer);
2734 if (POINTER_TYPE_P (type))
2738 If the type of the expression is "pointer to T," the type
2739 of the result is "T." */
2740 tree t = TREE_TYPE (type);
2742 if (CONVERT_EXPR_P (ptr)
2743 || TREE_CODE (ptr) == VIEW_CONVERT_EXPR)
2745 /* If a warning is issued, mark it to avoid duplicates from
2746 the backend. This only needs to be done at
2747 warn_strict_aliasing > 2. */
2748 if (warn_strict_aliasing > 2)
2749 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (ptr, 0)),
2750 type, TREE_OPERAND (ptr, 0)))
2751 TREE_NO_WARNING (ptr) = 1;
2754 if (VOID_TYPE_P (t))
2756 /* A pointer to incomplete type (other than cv void) can be
2757 dereferenced [expr.unary.op]/1 */
2758 if (complain & tf_error)
2759 error ("%qT is not a pointer-to-object type", type);
2760 return error_mark_node;
2762 else if (TREE_CODE (pointer) == ADDR_EXPR
2763 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2764 /* The POINTER was something like `&x'. We simplify `*&x' to
2766 return TREE_OPERAND (pointer, 0);
2769 tree ref = build1 (INDIRECT_REF, t, pointer);
2771 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2772 so that we get the proper error message if the result is used
2773 to assign to. Also, &* is supposed to be a no-op. */
2774 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2775 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2776 TREE_SIDE_EFFECTS (ref)
2777 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2781 else if (!(complain & tf_error))
2782 /* Don't emit any errors; we'll just return ERROR_MARK_NODE later. */
2784 /* `pointer' won't be an error_mark_node if we were given a
2785 pointer to member, so it's cool to check for this here. */
2786 else if (TYPE_PTR_TO_MEMBER_P (type))
2787 switch (errorstring)
2789 case RO_ARRAY_INDEXING:
2790 error ("invalid use of array indexing on pointer to member");
2793 error ("invalid use of unary %<*%> on pointer to member");
2795 case RO_IMPLICIT_CONVERSION:
2796 error ("invalid use of implicit conversion on pointer to member");
2801 else if (pointer != error_mark_node)
2802 switch (errorstring)
2805 error ("invalid type argument");
2807 case RO_ARRAY_INDEXING:
2808 error ("invalid type argument of array indexing");
2811 error ("invalid type argument of unary %<*%>");
2813 case RO_IMPLICIT_CONVERSION:
2814 error ("invalid type argument of implicit conversion");
2819 return error_mark_node;
2822 /* This handles expressions of the form "a[i]", which denotes
2825 This is logically equivalent in C to *(a+i), but we may do it differently.
2826 If A is a variable or a member, we generate a primitive ARRAY_REF.
2827 This avoids forcing the array out of registers, and can work on
2828 arrays that are not lvalues (for example, members of structures returned
2831 If INDEX is of some user-defined type, it must be converted to
2832 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2833 will inherit the type of the array, which will be some pointer type.
2835 LOC is the location to use in building the array reference. */
2838 build_array_ref (location_t loc, tree array, tree idx)
2844 error_at (loc, "subscript missing in array reference");
2845 return error_mark_node;
2848 if (TREE_TYPE (array) == error_mark_node
2849 || TREE_TYPE (idx) == error_mark_node)
2850 return error_mark_node;
2852 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2854 switch (TREE_CODE (array))
2858 tree value = build_array_ref (loc, TREE_OPERAND (array, 1), idx);
2859 ret = build2 (COMPOUND_EXPR, TREE_TYPE (value),
2860 TREE_OPERAND (array, 0), value);
2861 SET_EXPR_LOCATION (ret, loc);
2866 ret = build_conditional_expr
2867 (TREE_OPERAND (array, 0),
2868 build_array_ref (loc, TREE_OPERAND (array, 1), idx),
2869 build_array_ref (loc, TREE_OPERAND (array, 2), idx),
2870 tf_warning_or_error);
2871 protected_set_expr_location (ret, loc);
2878 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2882 warn_array_subscript_with_type_char (idx);
2884 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2886 error_at (loc, "array subscript is not an integer");
2887 return error_mark_node;
2890 /* Apply integral promotions *after* noticing character types.
2891 (It is unclear why we do these promotions -- the standard
2892 does not say that we should. In fact, the natural thing would
2893 seem to be to convert IDX to ptrdiff_t; we're performing
2894 pointer arithmetic.) */
2895 idx = perform_integral_promotions (idx);
2897 /* An array that is indexed by a non-constant
2898 cannot be stored in a register; we must be able to do
2899 address arithmetic on its address.
2900 Likewise an array of elements of variable size. */
2901 if (TREE_CODE (idx) != INTEGER_CST
2902 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2903 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2906 if (!cxx_mark_addressable (array))
2907 return error_mark_node;
2910 /* An array that is indexed by a constant value which is not within
2911 the array bounds cannot be stored in a register either; because we
2912 would get a crash in store_bit_field/extract_bit_field when trying
2913 to access a non-existent part of the register. */
2914 if (TREE_CODE (idx) == INTEGER_CST
2915 && TYPE_DOMAIN (TREE_TYPE (array))
2916 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2918 if (!cxx_mark_addressable (array))
2919 return error_mark_node;
2922 if (!lvalue_p (array))
2923 pedwarn (loc, OPT_pedantic,
2924 "ISO C++ forbids subscripting non-lvalue array");
2926 /* Note in C++ it is valid to subscript a `register' array, since
2927 it is valid to take the address of something with that
2928 storage specification. */
2932 while (TREE_CODE (foo) == COMPONENT_REF)
2933 foo = TREE_OPERAND (foo, 0);
2934 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2935 warning_at (loc, OPT_Wextra,
2936 "subscripting array declared %<register%>");
2939 type = TREE_TYPE (TREE_TYPE (array));
2940 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2941 /* Array ref is const/volatile if the array elements are
2942 or if the array is.. */
2943 TREE_READONLY (rval)
2944 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2945 TREE_SIDE_EFFECTS (rval)
2946 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2947 TREE_THIS_VOLATILE (rval)
2948 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2949 ret = require_complete_type (fold_if_not_in_template (rval));
2950 protected_set_expr_location (ret, loc);
2955 tree ar = default_conversion (array);
2956 tree ind = default_conversion (idx);
2958 /* Put the integer in IND to simplify error checking. */
2959 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2966 if (ar == error_mark_node)
2969 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2971 error_at (loc, "subscripted value is neither array nor pointer");
2972 return error_mark_node;
2974 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2976 error_at (loc, "array subscript is not an integer");
2977 return error_mark_node;
2980 warn_array_subscript_with_type_char (idx);
2982 ret = cp_build_indirect_ref (cp_build_binary_op (input_location,
2984 tf_warning_or_error),
2986 tf_warning_or_error);
2987 protected_set_expr_location (ret, loc);
2992 /* Resolve a pointer to member function. INSTANCE is the object
2993 instance to use, if the member points to a virtual member.
2995 This used to avoid checking for virtual functions if basetype
2996 has no virtual functions, according to an earlier ANSI draft.
2997 With the final ISO C++ rules, such an optimization is
2998 incorrect: A pointer to a derived member can be static_cast
2999 to pointer-to-base-member, as long as the dynamic object
3000 later has the right member. */
3003 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
3005 if (TREE_CODE (function) == OFFSET_REF)
3006 function = TREE_OPERAND (function, 1);
3008 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
3010 tree idx, delta, e1, e2, e3, vtbl, basetype;
3011 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
3013 tree instance_ptr = *instance_ptrptr;
3014 tree instance_save_expr = 0;
3015 if (instance_ptr == error_mark_node)
3017 if (TREE_CODE (function) == PTRMEM_CST)
3019 /* Extracting the function address from a pmf is only
3020 allowed with -Wno-pmf-conversions. It only works for
3022 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
3023 e1 = convert (fntype, e1);
3028 error ("object missing in use of %qE", function);
3029 return error_mark_node;
3033 if (TREE_SIDE_EFFECTS (instance_ptr))
3034 instance_ptr = instance_save_expr = save_expr (instance_ptr);
3036 if (TREE_SIDE_EFFECTS (function))
3037 function = save_expr (function);
3039 /* Start by extracting all the information from the PMF itself. */
3040 e3 = pfn_from_ptrmemfunc (function);
3041 delta = delta_from_ptrmemfunc (function);
3042 idx = build1 (NOP_EXPR, vtable_index_type, e3);
3043 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
3045 case ptrmemfunc_vbit_in_pfn:
3046 e1 = cp_build_binary_op (input_location,
3047 BIT_AND_EXPR, idx, integer_one_node,
3048 tf_warning_or_error);
3049 idx = cp_build_binary_op (input_location,
3050 MINUS_EXPR, idx, integer_one_node,
3051 tf_warning_or_error);
3054 case ptrmemfunc_vbit_in_delta:
3055 e1 = cp_build_binary_op (input_location,
3056 BIT_AND_EXPR, delta, integer_one_node,
3057 tf_warning_or_error);
3058 delta = cp_build_binary_op (input_location,
3059 RSHIFT_EXPR, delta, integer_one_node,
3060 tf_warning_or_error);
3067 /* Convert down to the right base before using the instance. A
3068 special case is that in a pointer to member of class C, C may
3069 be incomplete. In that case, the function will of course be
3070 a member of C, and no conversion is required. In fact,
3071 lookup_base will fail in that case, because incomplete
3072 classes do not have BINFOs. */
3073 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
3074 if (!same_type_ignoring_top_level_qualifiers_p
3075 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
3077 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
3078 basetype, ba_check, NULL);
3079 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
3081 if (instance_ptr == error_mark_node)
3082 return error_mark_node;
3084 /* ...and then the delta in the PMF. */
3085 instance_ptr = build2 (POINTER_PLUS_EXPR, TREE_TYPE (instance_ptr),
3086 instance_ptr, fold_convert (sizetype, delta));
3088 /* Hand back the adjusted 'this' argument to our caller. */
3089 *instance_ptrptr = instance_ptr;
3091 /* Next extract the vtable pointer from the object. */
3092 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
3094 vtbl = cp_build_indirect_ref (vtbl, RO_NULL, tf_warning_or_error);
3095 /* If the object is not dynamic the access invokes undefined
3096 behavior. As it is not executed in this case silence the
3097 spurious warnings it may provoke. */
3098 TREE_NO_WARNING (vtbl) = 1;
3100 /* Finally, extract the function pointer from the vtable. */
3101 e2 = fold_build2_loc (input_location,
3102 POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl,
3103 fold_convert (sizetype, idx));
3104 e2 = cp_build_indirect_ref (e2, RO_NULL, tf_warning_or_error);
3105 TREE_CONSTANT (e2) = 1;
3107 /* When using function descriptors, the address of the
3108 vtable entry is treated as a function pointer. */
3109 if (TARGET_VTABLE_USES_DESCRIPTORS)
3110 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
3111 cp_build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1,
3112 tf_warning_or_error));
3114 e2 = fold_convert (TREE_TYPE (e3), e2);
3115 e1 = build_conditional_expr (e1, e2, e3, tf_warning_or_error);
3117 /* Make sure this doesn't get evaluated first inside one of the
3118 branches of the COND_EXPR. */
3119 if (instance_save_expr)
3120 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
3121 instance_save_expr, e1);
3128 /* Used by the C-common bits. */
3130 build_function_call (location_t loc ATTRIBUTE_UNUSED,
3131 tree function, tree params)
3133 return cp_build_function_call (function, params, tf_warning_or_error);
3136 /* Used by the C-common bits. */
3138 build_function_call_vec (location_t loc ATTRIBUTE_UNUSED,
3139 tree function, VEC(tree,gc) *params,
3140 VEC(tree,gc) *origtypes ATTRIBUTE_UNUSED)
3142 VEC(tree,gc) *orig_params = params;
3143 tree ret = cp_build_function_call_vec (function, ¶ms,
3144 tf_warning_or_error);
3146 /* cp_build_function_call_vec can reallocate PARAMS by adding
3147 default arguments. That should never happen here. Verify
3149 gcc_assert (params == orig_params);
3154 /* Build a function call using a tree list of arguments. */
3157 cp_build_function_call (tree function, tree params, tsubst_flags_t complain)
3162 vec = make_tree_vector ();
3163 for (; params != NULL_TREE; params = TREE_CHAIN (params))
3164 VEC_safe_push (tree, gc, vec, TREE_VALUE (params));
3165 ret = cp_build_function_call_vec (function, &vec, complain);
3166 release_tree_vector (vec);
3170 /* Build a function call using a vector of arguments. PARAMS may be
3171 NULL if there are no parameters. This changes the contents of
3175 cp_build_function_call_vec (tree function, VEC(tree,gc) **params,
3176 tsubst_flags_t complain)
3178 tree fntype, fndecl;
3180 tree original = function;
3184 VEC(tree,gc) *allocated = NULL;
3187 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
3188 expressions, like those used for ObjC messenger dispatches. */
3189 if (params != NULL && !VEC_empty (tree, *params))
3190 function = objc_rewrite_function_call (function,
3191 VEC_index (tree, *params, 0));
3193 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3194 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
3195 if (TREE_CODE (function) == NOP_EXPR
3196 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
3197 function = TREE_OPERAND (function, 0);
3199 if (TREE_CODE (function) == FUNCTION_DECL)
3201 mark_used (function);
3204 /* Convert anything with function type to a pointer-to-function. */
3205 if (DECL_MAIN_P (function) && (complain & tf_error))
3206 pedwarn (input_location, OPT_pedantic,
3207 "ISO C++ forbids calling %<::main%> from within program");
3209 function = build_addr_func (function);
3215 function = build_addr_func (function);
3218 if (function == error_mark_node)
3219 return error_mark_node;
3221 fntype = TREE_TYPE (function);
3223 if (TYPE_PTRMEMFUNC_P (fntype))
3225 if (complain & tf_error)
3226 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
3227 "function in %<%E (...)%>, e.g. %<(... ->* %E) (...)%>",
3228 original, original);
3229 return error_mark_node;
3232 is_method = (TREE_CODE (fntype) == POINTER_TYPE
3233 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
3235 if (!((TREE_CODE (fntype) == POINTER_TYPE
3236 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
3238 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
3240 if (complain & tf_error)
3241 error ("%qE cannot be used as a function", original);
3242 return error_mark_node;
3245 /* fntype now gets the type of function pointed to. */
3246 fntype = TREE_TYPE (fntype);
3247 parm_types = TYPE_ARG_TYPES (fntype);
3251 allocated = make_tree_vector ();
3252 params = &allocated;
3255 nargs = convert_arguments (parm_types, params, fndecl, LOOKUP_NORMAL,
3258 return error_mark_node;
3260 argarray = VEC_address (tree, *params);
3262 /* Check for errors in format strings and inappropriately
3264 check_function_arguments (TYPE_ATTRIBUTES (fntype), nargs, argarray,
3267 ret = build_cxx_call (function, nargs, argarray);
3269 if (allocated != NULL)
3270 release_tree_vector (allocated);
3275 /* Convert the actual parameter expressions in the list VALUES to the
3276 types in the list TYPELIST. The converted expressions are stored
3277 back in the VALUES vector.
3278 If parmdecls is exhausted, or when an element has NULL as its type,
3279 perform the default conversions.
3281 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
3283 This is also where warnings about wrong number of args are generated.
3285 Returns the actual number of arguments processed (which might be less
3286 than the length of the vector), or -1 on error.
3288 In C++, unspecified trailing parameters can be filled in with their
3289 default arguments, if such were specified. Do so here. */
3292 convert_arguments (tree typelist, VEC(tree,gc) **values, tree fndecl,
3293 int flags, tsubst_flags_t complain)
3296 const char *called_thing = 0;
3299 /* Argument passing is always copy-initialization. */
3300 flags |= LOOKUP_ONLYCONVERTING;
3304 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
3306 if (DECL_NAME (fndecl) == NULL_TREE
3307 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
3308 called_thing = "constructor";
3310 called_thing = "member function";
3313 called_thing = "function";
3316 for (i = 0, typetail = typelist;
3317 i < VEC_length (tree, *values);
3320 tree type = typetail ? TREE_VALUE (typetail) : 0;
3321 tree val = VEC_index (tree, *values, i);
3323 if (val == error_mark_node || type == error_mark_node)
3326 if (type == void_type_node)
3328 if (complain & tf_error)
3332 error_at (input_location, "too many arguments to %s %q#D",
3333 called_thing, fndecl);
3334 inform (DECL_SOURCE_LOCATION (fndecl),
3338 error ("too many arguments to function");
3345 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3346 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
3347 if (TREE_CODE (val) == NOP_EXPR
3348 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
3349 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
3350 val = TREE_OPERAND (val, 0);
3352 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
3354 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
3355 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
3356 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
3357 val = decay_conversion (val);
3360 if (val == error_mark_node)
3365 /* Formal parm type is specified by a function prototype. */
3368 if (!COMPLETE_TYPE_P (complete_type (type)))
3370 if (complain & tf_error)
3373 error ("parameter %P of %qD has incomplete type %qT",
3376 error ("parameter %P has incomplete type %qT", i, type);
3378 parmval = error_mark_node;
3382 parmval = convert_for_initialization
3383 (NULL_TREE, type, val, flags,
3384 "argument passing", fndecl, i, complain);
3385 parmval = convert_for_arg_passing (type, parmval);
3388 if (parmval == error_mark_node)
3391 VEC_replace (tree, *values, i, parmval);
3395 if (fndecl && DECL_BUILT_IN (fndecl)
3396 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
3397 /* Don't do ellipsis conversion for __built_in_constant_p
3398 as this will result in spurious errors for non-trivial
3400 val = require_complete_type (val);
3402 val = convert_arg_to_ellipsis (val);
3404 VEC_replace (tree, *values, i, val);
3408 typetail = TREE_CHAIN (typetail);
3411 if (typetail != 0 && typetail != void_list_node)
3413 /* See if there are default arguments that can be used. Because
3414 we hold default arguments in the FUNCTION_TYPE (which is so
3415 wrong), we can see default parameters here from deduced
3416 contexts (and via typeof) for indirect function calls.
3417 Fortunately we know whether we have a function decl to
3418 provide default arguments in a language conformant
3420 if (fndecl && TREE_PURPOSE (typetail)
3421 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
3423 for (; typetail != void_list_node; ++i)
3426 = convert_default_arg (TREE_VALUE (typetail),
3427 TREE_PURPOSE (typetail),
3430 if (parmval == error_mark_node)
3433 VEC_safe_push (tree, gc, *values, parmval);
3434 typetail = TREE_CHAIN (typetail);
3435 /* ends with `...'. */
3436 if (typetail == NULL_TREE)
3442 if (complain & tf_error)
3446 error_at (input_location, "too few arguments to %s %q#D",
3447 called_thing, fndecl);
3448 inform (DECL_SOURCE_LOCATION (fndecl),
3452 error ("too few arguments to function");
3461 /* Build a binary-operation expression, after performing default
3462 conversions on the operands. CODE is the kind of expression to
3463 build. ARG1 and ARG2 are the arguments. ARG1_CODE and ARG2_CODE
3464 are the tree codes which correspond to ARG1 and ARG2 when issuing
3465 warnings about possibly misplaced parentheses. They may differ
3466 from the TREE_CODE of ARG1 and ARG2 if the parser has done constant
3467 folding (e.g., if the parser sees "a | 1 + 1", it may call this
3468 routine with ARG2 being an INTEGER_CST and ARG2_CODE == PLUS_EXPR).
3469 To avoid issuing any parentheses warnings, pass ARG1_CODE and/or
3470 ARG2_CODE as ERROR_MARK. */
3473 build_x_binary_op (enum tree_code code, tree arg1, enum tree_code arg1_code,
3474 tree arg2, enum tree_code arg2_code, bool *overloaded_p,
3475 tsubst_flags_t complain)
3484 if (processing_template_decl)
3486 if (type_dependent_expression_p (arg1)
3487 || type_dependent_expression_p (arg2))
3488 return build_min_nt (code, arg1, arg2);
3489 arg1 = build_non_dependent_expr (arg1);
3490 arg2 = build_non_dependent_expr (arg2);
3493 if (code == DOTSTAR_EXPR)
3494 expr = build_m_component_ref (arg1, arg2);
3496 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3497 overloaded_p, complain);
3499 /* Check for cases such as x+y<<z which users are likely to
3500 misinterpret. But don't warn about obj << x + y, since that is a
3501 common idiom for I/O. */
3502 if (warn_parentheses
3503 && (complain & tf_warning)
3504 && !processing_template_decl
3505 && !error_operand_p (arg1)
3506 && !error_operand_p (arg2)
3507 && (code != LSHIFT_EXPR
3508 || !CLASS_TYPE_P (TREE_TYPE (arg1))))
3509 warn_about_parentheses (code, arg1_code, orig_arg1, arg2_code, orig_arg2);
3511 if (processing_template_decl && expr != error_mark_node)
3512 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
3517 /* Build and return an ARRAY_REF expression. */
3520 build_x_array_ref (tree arg1, tree arg2, tsubst_flags_t complain)
3522 tree orig_arg1 = arg1;
3523 tree orig_arg2 = arg2;
3526 if (processing_template_decl)
3528 if (type_dependent_expression_p (arg1)
3529 || type_dependent_expression_p (arg2))
3530 return build_min_nt (ARRAY_REF, arg1, arg2,
3531 NULL_TREE, NULL_TREE);
3532 arg1 = build_non_dependent_expr (arg1);
3533 arg2 = build_non_dependent_expr (arg2);
3536 expr = build_new_op (ARRAY_REF, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3537 /*overloaded_p=*/NULL, complain);
3539 if (processing_template_decl && expr != error_mark_node)
3540 return build_min_non_dep (ARRAY_REF, expr, orig_arg1, orig_arg2,
3541 NULL_TREE, NULL_TREE);
3545 /* For the c-common bits. */
3547 build_binary_op (location_t location, enum tree_code code, tree op0, tree op1,
3548 int convert_p ATTRIBUTE_UNUSED)
3550 return cp_build_binary_op (location, code, op0, op1, tf_warning_or_error);
3554 /* Build a binary-operation expression without default conversions.
3555 CODE is the kind of expression to build.
3556 LOCATION is the location_t of the operator in the source code.
3557 This function differs from `build' in several ways:
3558 the data type of the result is computed and recorded in it,
3559 warnings are generated if arg data types are invalid,
3560 special handling for addition and subtraction of pointers is known,
3561 and some optimization is done (operations on narrow ints
3562 are done in the narrower type when that gives the same result).
3563 Constant folding is also done before the result is returned.
3565 Note that the operands will never have enumeral types
3566 because either they have just had the default conversions performed
3567 or they have both just been converted to some other type in which
3568 the arithmetic is to be done.
3570 C++: must do special pointer arithmetic when implementing
3571 multiple inheritance, and deal with pointer to member functions. */
3574 cp_build_binary_op (location_t location,
3575 enum tree_code code, tree orig_op0, tree orig_op1,
3576 tsubst_flags_t complain)
3579 enum tree_code code0, code1;
3581 const char *invalid_op_diag;
3583 /* Expression code to give to the expression when it is built.
3584 Normally this is CODE, which is what the caller asked for,
3585 but in some special cases we change it. */
3586 enum tree_code resultcode = code;
3588 /* Data type in which the computation is to be performed.
3589 In the simplest cases this is the common type of the arguments. */
3590 tree result_type = NULL;
3592 /* Nonzero means operands have already been type-converted
3593 in whatever way is necessary.
3594 Zero means they need to be converted to RESULT_TYPE. */
3597 /* Nonzero means create the expression with this type, rather than
3599 tree build_type = 0;
3601 /* Nonzero means after finally constructing the expression
3602 convert it to this type. */
3603 tree final_type = 0;
3607 /* Nonzero if this is an operation like MIN or MAX which can
3608 safely be computed in short if both args are promoted shorts.
3609 Also implies COMMON.
3610 -1 indicates a bitwise operation; this makes a difference
3611 in the exact conditions for when it is safe to do the operation
3612 in a narrower mode. */
3615 /* Nonzero if this is a comparison operation;
3616 if both args are promoted shorts, compare the original shorts.
3617 Also implies COMMON. */
3618 int short_compare = 0;
3620 /* Nonzero means set RESULT_TYPE to the common type of the args. */
3623 /* True if both operands have arithmetic type. */
3624 bool arithmetic_types_p;
3626 /* Apply default conversions. */
3630 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
3631 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
3632 || code == TRUTH_XOR_EXPR)
3634 if (!really_overloaded_fn (op0))
3635 op0 = decay_conversion (op0);
3636 if (!really_overloaded_fn (op1))
3637 op1 = decay_conversion (op1);
3641 if (!really_overloaded_fn (op0))
3642 op0 = default_conversion (op0);
3643 if (!really_overloaded_fn (op1))
3644 op1 = default_conversion (op1);
3647 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3648 STRIP_TYPE_NOPS (op0);
3649 STRIP_TYPE_NOPS (op1);
3651 /* DTRT if one side is an overloaded function, but complain about it. */
3652 if (type_unknown_p (op0))
3654 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3655 if (t != error_mark_node)
3657 if (complain & tf_error)
3658 permerror (input_location, "assuming cast to type %qT from overloaded function",
3663 if (type_unknown_p (op1))
3665 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3666 if (t != error_mark_node)
3668 if (complain & tf_error)
3669 permerror (input_location, "assuming cast to type %qT from overloaded function",
3675 type0 = TREE_TYPE (op0);
3676 type1 = TREE_TYPE (op1);
3678 /* The expression codes of the data types of the arguments tell us
3679 whether the arguments are integers, floating, pointers, etc. */
3680 code0 = TREE_CODE (type0);
3681 code1 = TREE_CODE (type1);
3683 /* If an error was already reported for one of the arguments,
3684 avoid reporting another error. */
3685 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3686 return error_mark_node;
3688 if ((invalid_op_diag
3689 = targetm.invalid_binary_op (code, type0, type1)))
3691 error (invalid_op_diag);
3692 return error_mark_node;
3695 /* Issue warnings about peculiar, but valid, uses of NULL. */
3696 if ((orig_op0 == null_node || orig_op1 == null_node)
3697 /* It's reasonable to use pointer values as operands of &&
3698 and ||, so NULL is no exception. */
3699 && code != TRUTH_ANDIF_EXPR && code != TRUTH_ORIF_EXPR
3700 && ( /* Both are NULL (or 0) and the operation was not a
3701 comparison or a pointer subtraction. */
3702 (null_ptr_cst_p (orig_op0) && null_ptr_cst_p (orig_op1)
3703 && code != EQ_EXPR && code != NE_EXPR && code != MINUS_EXPR)
3704 /* Or if one of OP0 or OP1 is neither a pointer nor NULL. */
3705 || (!null_ptr_cst_p (orig_op0)
3706 && !TYPE_PTR_P (type0) && !TYPE_PTR_TO_MEMBER_P (type0))
3707 || (!null_ptr_cst_p (orig_op1)
3708 && !TYPE_PTR_P (type1) && !TYPE_PTR_TO_MEMBER_P (type1)))
3709 && (complain & tf_warning))
3710 /* Some sort of arithmetic operation involving NULL was
3712 warning (OPT_Wpointer_arith, "NULL used in arithmetic");
3717 /* Subtraction of two similar pointers.
3718 We must subtract them as integers, then divide by object size. */
3719 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3720 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3722 return pointer_diff (op0, op1, common_pointer_type (type0, type1));
3723 /* In all other cases except pointer - int, the usual arithmetic
3725 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
3730 /* The pointer - int case is just like pointer + int; fall
3733 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
3734 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
3738 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
3739 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
3740 if (processing_template_decl)
3742 result_type = TREE_TYPE (ptr_operand);
3745 return cp_pointer_int_sum (code,
3756 case TRUNC_DIV_EXPR:
3758 case FLOOR_DIV_EXPR:
3759 case ROUND_DIV_EXPR:
3760 case EXACT_DIV_EXPR:
3761 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3762 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3763 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3764 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3766 enum tree_code tcode0 = code0, tcode1 = code1;
3768 warn_for_div_by_zero (location, op1);
3770 if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE)
3771 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3772 if (tcode1 == COMPLEX_TYPE || tcode1 == VECTOR_TYPE)
3773 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3775 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
3776 resultcode = RDIV_EXPR;
3778 /* When dividing two signed integers, we have to promote to int.
3779 unless we divide by a constant != -1. Note that default
3780 conversion will have been performed on the operands at this
3781 point, so we have to dig out the original type to find out if
3783 shorten = ((TREE_CODE (op0) == NOP_EXPR
3784 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3785 || (TREE_CODE (op1) == INTEGER_CST
3786 && ! integer_all_onesp (op1)));
3795 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3796 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3797 && !VECTOR_FLOAT_TYPE_P (type0)
3798 && !VECTOR_FLOAT_TYPE_P (type1)))
3802 case TRUNC_MOD_EXPR:
3803 case FLOOR_MOD_EXPR:
3804 warn_for_div_by_zero (location, op1);
3806 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3807 && TREE_CODE (TREE_TYPE (type0)) == INTEGER_TYPE
3808 && TREE_CODE (TREE_TYPE (type1)) == INTEGER_TYPE)
3810 else if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3812 /* Although it would be tempting to shorten always here, that loses
3813 on some targets, since the modulo instruction is undefined if the
3814 quotient can't be represented in the computation mode. We shorten
3815 only if unsigned or if dividing by something we know != -1. */
3816 shorten = ((TREE_CODE (op0) == NOP_EXPR
3817 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3818 || (TREE_CODE (op1) == INTEGER_CST
3819 && ! integer_all_onesp (op1)));
3824 case TRUTH_ANDIF_EXPR:
3825 case TRUTH_ORIF_EXPR:
3826 case TRUTH_AND_EXPR:
3828 result_type = boolean_type_node;
3831 /* Shift operations: result has same type as first operand;
3832 always convert second operand to int.
3833 Also set SHORT_SHIFT if shifting rightward. */
3836 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3838 result_type = type0;
3839 if (TREE_CODE (op1) == INTEGER_CST)
3841 if (tree_int_cst_lt (op1, integer_zero_node))
3843 if ((complain & tf_warning)
3844 && c_inhibit_evaluation_warnings == 0)
3845 warning (0, "right shift count is negative");
3849 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0
3850 && (complain & tf_warning)
3851 && c_inhibit_evaluation_warnings == 0)
3852 warning (0, "right shift count >= width of type");
3855 /* Convert the shift-count to an integer, regardless of
3856 size of value being shifted. */
3857 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3858 op1 = cp_convert (integer_type_node, op1);
3859 /* Avoid converting op1 to result_type later. */
3865 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3867 result_type = type0;
3868 if (TREE_CODE (op1) == INTEGER_CST)
3870 if (tree_int_cst_lt (op1, integer_zero_node))
3872 if ((complain & tf_warning)
3873 && c_inhibit_evaluation_warnings == 0)
3874 warning (0, "left shift count is negative");
3876 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3878 if ((complain & tf_warning)
3879 && c_inhibit_evaluation_warnings == 0)
3880 warning (0, "left shift count >= width of type");
3883 /* Convert the shift-count to an integer, regardless of
3884 size of value being shifted. */
3885 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3886 op1 = cp_convert (integer_type_node, op1);
3887 /* Avoid converting op1 to result_type later. */
3894 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3896 result_type = type0;
3897 if (TREE_CODE (op1) == INTEGER_CST)
3899 if (tree_int_cst_lt (op1, integer_zero_node))
3901 if (complain & tf_warning)
3902 warning (0, (code == LROTATE_EXPR)
3903 ? G_("left rotate count is negative")
3904 : G_("right rotate count is negative"));
3906 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3908 if (complain & tf_warning)
3909 warning (0, (code == LROTATE_EXPR)
3910 ? G_("left rotate count >= width of type")
3911 : G_("right rotate count >= width of type"));
3914 /* Convert the shift-count to an integer, regardless of
3915 size of value being shifted. */
3916 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3917 op1 = cp_convert (integer_type_node, op1);
3923 if ((complain & tf_warning)
3924 && (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1)))
3925 warning (OPT_Wfloat_equal,
3926 "comparing floating point with == or != is unsafe");
3927 if ((complain & tf_warning)
3928 && ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3929 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0))))
3930 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3932 build_type = boolean_type_node;
3933 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3934 || code0 == COMPLEX_TYPE || code0 == ENUMERAL_TYPE)
3935 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3936 || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE))
3938 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3939 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3940 result_type = composite_pointer_type (type0, type1, op0, op1,
3941 CPO_COMPARISON, complain);
3942 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3943 && null_ptr_cst_p (op1))
3945 if (TREE_CODE (op0) == ADDR_EXPR
3946 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
3948 if (complain & tf_warning)
3949 warning (OPT_Waddress, "the address of %qD will never be NULL",
3950 TREE_OPERAND (op0, 0));
3952 result_type = type0;
3954 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3955 && null_ptr_cst_p (op0))
3957 if (TREE_CODE (op1) == ADDR_EXPR
3958 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
3960 if (complain & tf_warning)
3961 warning (OPT_Waddress, "the address of %qD will never be NULL",
3962 TREE_OPERAND (op1, 0));
3964 result_type = type1;
3966 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3968 result_type = type0;
3969 if (complain & tf_error)
3970 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3972 return error_mark_node;
3974 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3976 result_type = type1;
3977 if (complain & tf_error)
3978 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3980 return error_mark_node;
3982 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3984 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3985 == ptrmemfunc_vbit_in_delta)
3987 tree pfn0 = pfn_from_ptrmemfunc (op0);
3988 tree delta0 = delta_from_ptrmemfunc (op0);
3989 tree e1 = cp_build_binary_op (location,
3992 fold_convert (TREE_TYPE (pfn0),
3995 tree e2 = cp_build_binary_op (location,
4000 e2 = cp_build_binary_op (location,
4001 EQ_EXPR, e2, integer_zero_node,
4003 op0 = cp_build_binary_op (location,
4004 TRUTH_ANDIF_EXPR, e1, e2,
4006 op1 = cp_convert (TREE_TYPE (op0), integer_one_node);
4010 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
4011 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
4013 result_type = TREE_TYPE (op0);
4015 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
4016 return cp_build_binary_op (location, code, op1, op0, complain);
4017 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1))
4020 /* E will be the final comparison. */
4022 /* E1 and E2 are for scratch. */
4030 type = composite_pointer_type (type0, type1, op0, op1,
4031 CPO_COMPARISON, complain);
4033 if (!same_type_p (TREE_TYPE (op0), type))
4034 op0 = cp_convert_and_check (type, op0);
4035 if (!same_type_p (TREE_TYPE (op1), type))
4036 op1 = cp_convert_and_check (type, op1);
4038 if (op0 == error_mark_node || op1 == error_mark_node)
4039 return error_mark_node;
4041 if (TREE_SIDE_EFFECTS (op0))
4042 op0 = save_expr (op0);
4043 if (TREE_SIDE_EFFECTS (op1))
4044 op1 = save_expr (op1);
4046 pfn0 = pfn_from_ptrmemfunc (op0);
4047 pfn1 = pfn_from_ptrmemfunc (op1);
4048 delta0 = delta_from_ptrmemfunc (op0);
4049 delta1 = delta_from_ptrmemfunc (op1);
4050 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
4051 == ptrmemfunc_vbit_in_delta)
4056 && ((op0.delta == op1.delta)
4057 || (!op0.pfn && op0.delta & 1 == 0
4058 && op1.delta & 1 == 0))
4060 The reason for the `!op0.pfn' bit is that a NULL
4061 pointer-to-member is any member with a zero PFN and
4062 LSB of the DELTA field is 0. */
4064 e1 = cp_build_binary_op (location, BIT_AND_EXPR,
4068 e1 = cp_build_binary_op (location,
4069 EQ_EXPR, e1, integer_zero_node,
4071 e2 = cp_build_binary_op (location, BIT_AND_EXPR,
4075 e2 = cp_build_binary_op (location,
4076 EQ_EXPR, e2, integer_zero_node,
4078 e1 = cp_build_binary_op (location,
4079 TRUTH_ANDIF_EXPR, e2, e1,
4081 e2 = cp_build_binary_op (location, EQ_EXPR,
4083 fold_convert (TREE_TYPE (pfn0),
4086 e2 = cp_build_binary_op (location,
4087 TRUTH_ANDIF_EXPR, e2, e1, complain);
4088 e1 = cp_build_binary_op (location,
4089 EQ_EXPR, delta0, delta1, complain);
4090 e1 = cp_build_binary_op (location,
4091 TRUTH_ORIF_EXPR, e1, e2, complain);
4098 && (!op0.pfn || op0.delta == op1.delta))
4100 The reason for the `!op0.pfn' bit is that a NULL
4101 pointer-to-member is any member with a zero PFN; the
4102 DELTA field is unspecified. */
4104 e1 = cp_build_binary_op (location,
4105 EQ_EXPR, delta0, delta1, complain);
4106 e2 = cp_build_binary_op (location,
4109 fold_convert (TREE_TYPE (pfn0),
4112 e1 = cp_build_binary_op (location,
4113 TRUTH_ORIF_EXPR, e1, e2, complain);
4115 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
4116 e = cp_build_binary_op (location,
4117 TRUTH_ANDIF_EXPR, e2, e1, complain);
4118 if (code == EQ_EXPR)
4120 return cp_build_binary_op (location,
4121 EQ_EXPR, e, integer_zero_node, complain);
4125 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
4126 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
4128 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
4129 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
4137 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
4138 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
4140 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
4141 result_type = composite_pointer_type (type0, type1, op0, op1,
4142 CPO_COMPARISON, complain);
4149 if (TREE_CODE (orig_op0) == STRING_CST
4150 || TREE_CODE (orig_op1) == STRING_CST)
4152 if (complain & tf_warning)
4153 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
4156 build_type = boolean_type_node;
4157 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
4158 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
4160 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
4161 result_type = composite_pointer_type (type0, type1, op0, op1,
4162 CPO_COMPARISON, complain);
4163 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
4164 && integer_zerop (op1))
4165 result_type = type0;
4166 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
4167 && integer_zerop (op0))
4168 result_type = type1;
4169 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
4171 result_type = type0;
4172 if (complain & tf_error)
4173 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
4175 return error_mark_node;
4177 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
4179 result_type = type1;
4180 if (complain & tf_error)
4181 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
4183 return error_mark_node;
4187 case UNORDERED_EXPR:
4194 build_type = integer_type_node;
4195 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
4197 if (complain & tf_error)
4198 error ("unordered comparison on non-floating point argument");
4199 return error_mark_node;
4208 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE
4209 || code0 == ENUMERAL_TYPE)
4210 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
4211 || code1 == COMPLEX_TYPE || code1 == ENUMERAL_TYPE)))
4212 arithmetic_types_p = 1;
4215 arithmetic_types_p = 0;
4216 /* Vector arithmetic is only allowed when both sides are vectors. */
4217 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
4219 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
4220 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
4223 binary_op_error (location, code, type0, type1);
4224 return error_mark_node;
4226 arithmetic_types_p = 1;
4229 /* Determine the RESULT_TYPE, if it is not already known. */
4231 && arithmetic_types_p
4232 && (shorten || common || short_compare))
4233 result_type = cp_common_type (type0, type1);
4237 if (complain & tf_error)
4238 error ("invalid operands of types %qT and %qT to binary %qO",
4239 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
4240 return error_mark_node;
4243 /* If we're in a template, the only thing we need to know is the
4245 if (processing_template_decl)
4247 /* Since the middle-end checks the type when doing a build2, we
4248 need to build the tree in pieces. This built tree will never
4249 get out of the front-end as we replace it when instantiating
4251 tree tmp = build2 (resultcode,
4252 build_type ? build_type : result_type,
4254 TREE_OPERAND (tmp, 0) = op0;
4258 if (arithmetic_types_p)
4260 bool first_complex = (code0 == COMPLEX_TYPE);
4261 bool second_complex = (code1 == COMPLEX_TYPE);
4262 int none_complex = (!first_complex && !second_complex);
4264 /* Adapted from patch for c/24581. */
4265 if (first_complex != second_complex
4266 && (code == PLUS_EXPR
4267 || code == MINUS_EXPR
4268 || code == MULT_EXPR
4269 || (code == TRUNC_DIV_EXPR && first_complex))
4270 && TREE_CODE (TREE_TYPE (result_type)) == REAL_TYPE
4271 && flag_signed_zeros)
4273 /* An operation on mixed real/complex operands must be
4274 handled specially, but the language-independent code can
4275 more easily optimize the plain complex arithmetic if
4276 -fno-signed-zeros. */
4277 tree real_type = TREE_TYPE (result_type);
4281 if (TREE_TYPE (op0) != result_type)
4282 op0 = cp_convert_and_check (result_type, op0);
4283 if (TREE_TYPE (op1) != real_type)
4284 op1 = cp_convert_and_check (real_type, op1);
4288 if (TREE_TYPE (op0) != real_type)
4289 op0 = cp_convert_and_check (real_type, op0);
4290 if (TREE_TYPE (op1) != result_type)
4291 op1 = cp_convert_and_check (result_type, op1);
4293 if (TREE_CODE (op0) == ERROR_MARK || TREE_CODE (op1) == ERROR_MARK)
4294 return error_mark_node;
4297 op0 = save_expr (op0);
4298 real = cp_build_unary_op (REALPART_EXPR, op0, 1, complain);
4299 imag = cp_build_unary_op (IMAGPART_EXPR, op0, 1, complain);
4303 case TRUNC_DIV_EXPR:
4304 imag = build2 (resultcode, real_type, imag, op1);
4308 real = build2 (resultcode, real_type, real, op1);
4316 op1 = save_expr (op1);
4317 real = cp_build_unary_op (REALPART_EXPR, op1, 1, complain);
4318 imag = cp_build_unary_op (IMAGPART_EXPR, op1, 1, complain);
4322 imag = build2 (resultcode, real_type, op0, imag);
4325 real = build2 (resultcode, real_type, op0, real);
4328 real = build2 (resultcode, real_type, op0, real);
4329 imag = build1 (NEGATE_EXPR, real_type, imag);
4335 return build2 (COMPLEX_EXPR, result_type, real, imag);
4338 /* For certain operations (which identify themselves by shorten != 0)
4339 if both args were extended from the same smaller type,
4340 do the arithmetic in that type and then extend.
4342 shorten !=0 and !=1 indicates a bitwise operation.
4343 For them, this optimization is safe only if
4344 both args are zero-extended or both are sign-extended.
4345 Otherwise, we might change the result.
4346 E.g., (short)-1 | (unsigned short)-1 is (int)-1
4347 but calculated in (unsigned short) it would be (unsigned short)-1. */
4349 if (shorten && none_complex)
4351 final_type = result_type;
4352 result_type = shorten_binary_op (result_type, op0, op1,
4356 /* Comparison operations are shortened too but differently.
4357 They identify themselves by setting short_compare = 1. */
4361 /* Don't write &op0, etc., because that would prevent op0
4362 from being kept in a register.
4363 Instead, make copies of the our local variables and
4364 pass the copies by reference, then copy them back afterward. */
4365 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
4366 enum tree_code xresultcode = resultcode;
4368 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
4370 return cp_convert (boolean_type_node, val);
4371 op0 = xop0, op1 = xop1;
4373 resultcode = xresultcode;
4376 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
4377 && warn_sign_compare
4378 && !TREE_NO_WARNING (orig_op0)
4379 && !TREE_NO_WARNING (orig_op1)
4380 /* Do not warn until the template is instantiated; we cannot
4381 bound the ranges of the arguments until that point. */
4382 && !processing_template_decl
4383 && (complain & tf_warning)
4384 && c_inhibit_evaluation_warnings == 0)
4386 warn_for_sign_compare (location, orig_op0, orig_op1, op0, op1,
4387 result_type, resultcode);
4391 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
4392 Then the expression will be built.
4393 It will be given type FINAL_TYPE if that is nonzero;
4394 otherwise, it will be given type RESULT_TYPE. */
4397 if (TREE_TYPE (op0) != result_type)
4398 op0 = cp_convert_and_check (result_type, op0);
4399 if (TREE_TYPE (op1) != result_type)
4400 op1 = cp_convert_and_check (result_type, op1);
4402 if (op0 == error_mark_node || op1 == error_mark_node)
4403 return error_mark_node;
4406 if (build_type == NULL_TREE)
4407 build_type = result_type;
4409 result = build2 (resultcode, build_type, op0, op1);
4410 result = fold_if_not_in_template (result);
4411 if (final_type != 0)
4412 result = cp_convert (final_type, result);
4414 if (TREE_OVERFLOW_P (result)
4415 && !TREE_OVERFLOW_P (op0)
4416 && !TREE_OVERFLOW_P (op1))
4417 overflow_warning (location, result);
4422 /* Return a tree for the sum or difference (RESULTCODE says which)
4423 of pointer PTROP and integer INTOP. */
4426 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
4428 tree res_type = TREE_TYPE (ptrop);
4430 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
4431 in certain circumstance (when it's valid to do so). So we need
4432 to make sure it's complete. We don't need to check here, if we
4433 can actually complete it at all, as those checks will be done in
4434 pointer_int_sum() anyway. */
4435 complete_type (TREE_TYPE (res_type));
4437 return pointer_int_sum (input_location, resultcode, ptrop,
4438 fold_if_not_in_template (intop));
4441 /* Return a tree for the difference of pointers OP0 and OP1.
4442 The resulting tree has type int. */
4445 pointer_diff (tree op0, tree op1, tree ptrtype)
4448 tree restype = ptrdiff_type_node;
4449 tree target_type = TREE_TYPE (ptrtype);
4451 if (!complete_type_or_else (target_type, NULL_TREE))
4452 return error_mark_node;
4454 if (TREE_CODE (target_type) == VOID_TYPE)
4455 permerror (input_location, "ISO C++ forbids using pointer of type %<void *%> in subtraction");
4456 if (TREE_CODE (target_type) == FUNCTION_TYPE)
4457 permerror (input_location, "ISO C++ forbids using pointer to a function in subtraction");
4458 if (TREE_CODE (target_type) == METHOD_TYPE)
4459 permerror (input_location, "ISO C++ forbids using pointer to a method in subtraction");
4461 /* First do the subtraction as integers;
4462 then drop through to build the divide operator. */
4464 op0 = cp_build_binary_op (input_location,
4466 cp_convert (restype, op0),
4467 cp_convert (restype, op1),
4468 tf_warning_or_error);
4470 /* This generates an error if op1 is a pointer to an incomplete type. */
4471 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
4472 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
4474 op1 = (TYPE_PTROB_P (ptrtype)
4475 ? size_in_bytes (target_type)
4476 : integer_one_node);
4478 /* Do the division. */
4480 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
4481 return fold_if_not_in_template (result);
4484 /* Construct and perhaps optimize a tree representation
4485 for a unary operation. CODE, a tree_code, specifies the operation
4486 and XARG is the operand. */
4489 build_x_unary_op (enum tree_code code, tree xarg, tsubst_flags_t complain)
4491 tree orig_expr = xarg;
4495 if (processing_template_decl)
4497 if (type_dependent_expression_p (xarg))
4498 return build_min_nt (code, xarg, NULL_TREE);
4500 xarg = build_non_dependent_expr (xarg);
4505 /* [expr.unary.op] says:
4507 The address of an object of incomplete type can be taken.
4509 (And is just the ordinary address operator, not an overloaded
4510 "operator &".) However, if the type is a template
4511 specialization, we must complete the type at this point so that
4512 an overloaded "operator &" will be available if required. */
4513 if (code == ADDR_EXPR
4514 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
4515 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
4516 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
4517 || (TREE_CODE (xarg) == OFFSET_REF)))
4518 /* Don't look for a function. */;
4520 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
4521 /*overloaded_p=*/NULL, complain);
4522 if (!exp && code == ADDR_EXPR)
4524 if (is_overloaded_fn (xarg))
4526 tree fn = get_first_fn (xarg);
4527 if (DECL_CONSTRUCTOR_P (fn) || DECL_DESTRUCTOR_P (fn))
4529 error (DECL_CONSTRUCTOR_P (fn)
4530 ? G_("taking address of constructor %qE")
4531 : G_("taking address of destructor %qE"),
4533 return error_mark_node;
4537 /* A pointer to member-function can be formed only by saying
4539 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
4540 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
4542 if (TREE_CODE (xarg) != OFFSET_REF
4543 || !TYPE_P (TREE_OPERAND (xarg, 0)))
4545 error ("invalid use of %qE to form a pointer-to-member-function",
4547 if (TREE_CODE (xarg) != OFFSET_REF)
4548 inform (input_location, " a qualified-id is required");
4549 return error_mark_node;
4553 error ("parentheses around %qE cannot be used to form a"
4554 " pointer-to-member-function",
4556 PTRMEM_OK_P (xarg) = 1;
4560 if (TREE_CODE (xarg) == OFFSET_REF)
4562 ptrmem = PTRMEM_OK_P (xarg);
4564 if (!ptrmem && !flag_ms_extensions
4565 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
4567 /* A single non-static member, make sure we don't allow a
4568 pointer-to-member. */
4569 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
4570 TREE_OPERAND (xarg, 0),
4571 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
4572 PTRMEM_OK_P (xarg) = ptrmem;
4575 else if (TREE_CODE (xarg) == TARGET_EXPR && (complain & tf_warning))
4576 warning (0, "taking address of temporary");
4577 exp = cp_build_unary_op (ADDR_EXPR, xarg, 0, complain);
4580 if (processing_template_decl && exp != error_mark_node)
4581 exp = build_min_non_dep (code, exp, orig_expr,
4582 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
4583 if (TREE_CODE (exp) == ADDR_EXPR)
4584 PTRMEM_OK_P (exp) = ptrmem;
4588 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
4589 constants, where a null value is represented by an INTEGER_CST of
4593 cp_truthvalue_conversion (tree expr)
4595 tree type = TREE_TYPE (expr);
4596 if (TYPE_PTRMEM_P (type))
4597 return build_binary_op (EXPR_LOCATION (expr),
4598 NE_EXPR, expr, integer_zero_node, 1);
4600 return c_common_truthvalue_conversion (input_location, expr);
4603 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
4606 condition_conversion (tree expr)
4609 if (processing_template_decl)
4611 t = perform_implicit_conversion_flags (boolean_type_node, expr,
4612 tf_warning_or_error, LOOKUP_NORMAL);
4613 t = fold_build_cleanup_point_expr (boolean_type_node, t);
4617 /* Returns the address of T. This function will fold away
4618 ADDR_EXPR of INDIRECT_REF. */
4621 build_address (tree t)
4623 if (error_operand_p (t) || !cxx_mark_addressable (t))
4624 return error_mark_node;
4625 t = build_fold_addr_expr (t);
4626 if (TREE_CODE (t) != ADDR_EXPR)
4631 /* Returns the address of T with type TYPE. */
4634 build_typed_address (tree t, tree type)
4636 if (error_operand_p (t) || !cxx_mark_addressable (t))
4637 return error_mark_node;
4638 t = build_fold_addr_expr_with_type (t, type);
4639 if (TREE_CODE (t) != ADDR_EXPR)
4644 /* Return a NOP_EXPR converting EXPR to TYPE. */
4647 build_nop (tree type, tree expr)
4649 if (type == error_mark_node || error_operand_p (expr))
4651 return build1 (NOP_EXPR, type, expr);
4654 /* C++: Must handle pointers to members.
4656 Perhaps type instantiation should be extended to handle conversion
4657 from aggregates to types we don't yet know we want? (Or are those
4658 cases typically errors which should be reported?)
4660 NOCONVERT nonzero suppresses the default promotions
4661 (such as from short to int). */
4664 cp_build_unary_op (enum tree_code code, tree xarg, int noconvert,
4665 tsubst_flags_t complain)
4667 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
4670 const char *errstring = NULL;
4672 const char *invalid_op_diag;
4674 if (error_operand_p (arg))
4675 return error_mark_node;
4677 if ((invalid_op_diag
4678 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
4683 error (invalid_op_diag);
4684 return error_mark_node;
4689 case UNARY_PLUS_EXPR:
4692 int flags = WANT_ARITH | WANT_ENUM;
4693 /* Unary plus (but not unary minus) is allowed on pointers. */
4694 if (code == UNARY_PLUS_EXPR)
4695 flags |= WANT_POINTER;
4696 arg = build_expr_type_conversion (flags, arg, true);
4698 errstring = (code == NEGATE_EXPR
4699 ? _("wrong type argument to unary minus")
4700 : _("wrong type argument to unary plus"));
4703 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4704 arg = perform_integral_promotions (arg);
4706 /* Make sure the result is not an lvalue: a unary plus or minus
4707 expression is always a rvalue. */
4714 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4718 arg = default_conversion (arg);
4720 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM
4721 | WANT_VECTOR_OR_COMPLEX,
4723 errstring = _("wrong type argument to bit-complement");
4724 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4725 arg = perform_integral_promotions (arg);
4729 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4730 errstring = _("wrong type argument to abs");
4731 else if (!noconvert)
4732 arg = default_conversion (arg);
4736 /* Conjugating a real value is a no-op, but allow it anyway. */
4737 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4738 errstring = _("wrong type argument to conjugation");
4739 else if (!noconvert)
4740 arg = default_conversion (arg);
4743 case TRUTH_NOT_EXPR:
4744 arg = perform_implicit_conversion (boolean_type_node, arg,
4746 val = invert_truthvalue_loc (input_location, arg);
4747 if (arg != error_mark_node)
4749 errstring = _("in argument to unary !");
4756 if (TREE_CODE (arg) == COMPLEX_CST)
4757 return TREE_REALPART (arg);
4758 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4760 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4761 return fold_if_not_in_template (arg);
4767 if (TREE_CODE (arg) == COMPLEX_CST)
4768 return TREE_IMAGPART (arg);
4769 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4771 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4772 return fold_if_not_in_template (arg);
4775 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4777 case PREINCREMENT_EXPR:
4778 case POSTINCREMENT_EXPR:
4779 case PREDECREMENT_EXPR:
4780 case POSTDECREMENT_EXPR:
4781 /* Handle complex lvalues (when permitted)
4782 by reduction to simpler cases. */
4784 val = unary_complex_lvalue (code, arg);
4788 /* Increment or decrement the real part of the value,
4789 and don't change the imaginary part. */
4790 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4794 arg = stabilize_reference (arg);
4795 real = cp_build_unary_op (REALPART_EXPR, arg, 1, complain);
4796 imag = cp_build_unary_op (IMAGPART_EXPR, arg, 1, complain);
4797 real = cp_build_unary_op (code, real, 1, complain);
4798 if (real == error_mark_node || imag == error_mark_node)
4799 return error_mark_node;
4800 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4804 /* Report invalid types. */
4806 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4809 if (code == PREINCREMENT_EXPR)
4810 errstring = _("no pre-increment operator for type");
4811 else if (code == POSTINCREMENT_EXPR)
4812 errstring = _("no post-increment operator for type");
4813 else if (code == PREDECREMENT_EXPR)
4814 errstring = _("no pre-decrement operator for type");
4816 errstring = _("no post-decrement operator for type");
4819 else if (arg == error_mark_node)
4820 return error_mark_node;
4822 /* Report something read-only. */
4824 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4825 || TREE_READONLY (arg))
4827 if (complain & tf_error)
4828 readonly_error (arg, ((code == PREINCREMENT_EXPR
4829 || code == POSTINCREMENT_EXPR)
4830 ? REK_INCREMENT : REK_DECREMENT));
4832 return error_mark_node;
4837 tree declared_type = unlowered_expr_type (arg);
4839 argtype = TREE_TYPE (arg);
4841 /* ARM $5.2.5 last annotation says this should be forbidden. */
4842 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4844 if (complain & tf_error)
4845 permerror (input_location, (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4846 ? G_("ISO C++ forbids incrementing an enum")
4847 : G_("ISO C++ forbids decrementing an enum"));
4849 return error_mark_node;
4852 /* Compute the increment. */
4854 if (TREE_CODE (argtype) == POINTER_TYPE)
4856 tree type = complete_type (TREE_TYPE (argtype));
4858 if (!COMPLETE_OR_VOID_TYPE_P (type))
4860 if (complain & tf_error)
4861 error (((code == PREINCREMENT_EXPR
4862 || code == POSTINCREMENT_EXPR))
4863 ? G_("cannot increment a pointer to incomplete type %qT")
4864 : G_("cannot decrement a pointer to incomplete type %qT"),
4865 TREE_TYPE (argtype));
4867 return error_mark_node;
4869 else if ((pedantic || warn_pointer_arith)
4870 && !TYPE_PTROB_P (argtype))
4872 if (complain & tf_error)
4873 permerror (input_location, (code == PREINCREMENT_EXPR
4874 || code == POSTINCREMENT_EXPR)
4875 ? G_("ISO C++ forbids incrementing a pointer of type %qT")
4876 : G_("ISO C++ forbids decrementing a pointer of type %qT"),
4879 return error_mark_node;
4882 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4885 inc = integer_one_node;
4887 inc = cp_convert (argtype, inc);
4889 /* Complain about anything else that is not a true lvalue. */
4890 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4891 || code == POSTINCREMENT_EXPR)
4892 ? lv_increment : lv_decrement),
4894 return error_mark_node;
4896 /* Forbid using -- on `bool'. */
4897 if (TREE_CODE (declared_type) == BOOLEAN_TYPE)
4899 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4901 if (complain & tf_error)
4902 error ("invalid use of Boolean expression as operand "
4903 "to %<operator--%>");
4904 return error_mark_node;
4906 val = boolean_increment (code, arg);
4909 val = build2 (code, TREE_TYPE (arg), arg, inc);
4911 TREE_SIDE_EFFECTS (val) = 1;
4916 /* Note that this operation never does default_conversion
4917 regardless of NOCONVERT. */
4919 argtype = lvalue_type (arg);
4921 if (TREE_CODE (arg) == OFFSET_REF)
4924 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4926 tree type = build_pointer_type (TREE_TYPE (argtype));
4927 arg = build1 (CONVERT_EXPR, type, arg);
4930 else if (pedantic && DECL_MAIN_P (arg))
4933 /* Apparently a lot of autoconf scripts for C++ packages do this,
4934 so only complain if -pedantic. */
4935 if (complain & (flag_pedantic_errors ? tf_error : tf_warning))
4936 pedwarn (input_location, OPT_pedantic,
4937 "ISO C++ forbids taking address of function %<::main%>");
4938 else if (flag_pedantic_errors)
4939 return error_mark_node;
4942 /* Let &* cancel out to simplify resulting code. */
4943 if (TREE_CODE (arg) == INDIRECT_REF)
4945 /* We don't need to have `current_class_ptr' wrapped in a
4946 NON_LVALUE_EXPR node. */
4947 if (arg == current_class_ref)
4948 return current_class_ptr;
4950 arg = TREE_OPERAND (arg, 0);
4951 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4953 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4954 arg = build1 (CONVERT_EXPR, type, arg);
4957 /* Don't let this be an lvalue. */
4962 /* Uninstantiated types are all functions. Taking the
4963 address of a function is a no-op, so just return the
4966 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4967 || !IDENTIFIER_OPNAME_P (arg));
4969 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4970 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4972 /* They're trying to take the address of a unique non-static
4973 member function. This is ill-formed (except in MS-land),
4974 but let's try to DTRT.
4975 Note: We only handle unique functions here because we don't
4976 want to complain if there's a static overload; non-unique
4977 cases will be handled by instantiate_type. But we need to
4978 handle this case here to allow casts on the resulting PMF.
4979 We could defer this in non-MS mode, but it's easier to give
4980 a useful error here. */
4982 /* Inside constant member functions, the `this' pointer
4983 contains an extra const qualifier. TYPE_MAIN_VARIANT
4984 is used here to remove this const from the diagnostics
4985 and the created OFFSET_REF. */
4986 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4987 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4990 if (! flag_ms_extensions)
4992 tree name = DECL_NAME (fn);
4993 if (!(complain & tf_error))
4994 return error_mark_node;
4995 else if (current_class_type
4996 && TREE_OPERAND (arg, 0) == current_class_ref)
4997 /* An expression like &memfn. */
4998 permerror (input_location, "ISO C++ forbids taking the address of an unqualified"
4999 " or parenthesized non-static member function to form"
5000 " a pointer to member function. Say %<&%T::%D%>",
5003 permerror (input_location, "ISO C++ forbids taking the address of a bound member"
5004 " function to form a pointer to member function."
5008 arg = build_offset_ref (base, fn, /*address_p=*/true);
5012 if (type_unknown_p (arg))
5013 return build1 (ADDR_EXPR, unknown_type_node, arg);
5015 /* Handle complex lvalues (when permitted)
5016 by reduction to simpler cases. */
5017 val = unary_complex_lvalue (code, arg);
5021 switch (TREE_CODE (arg))
5025 case FIX_TRUNC_EXPR:
5026 /* Even if we're not being pedantic, we cannot allow this
5027 extension when we're instantiating in a SFINAE
5029 if (! lvalue_p (arg) && complain == tf_none)
5031 if (complain & tf_error)
5032 permerror (input_location, "ISO C++ forbids taking the address of a cast to a non-lvalue expression");
5034 return error_mark_node;
5039 arg = BASELINK_FUNCTIONS (arg);
5043 arg = OVL_CURRENT (arg);
5047 /* Turn a reference to a non-static data member into a
5048 pointer-to-member. */
5053 if (!PTRMEM_OK_P (arg))
5054 return cp_build_unary_op (code, arg, 0, complain);
5056 t = TREE_OPERAND (arg, 1);
5057 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
5059 if (complain & tf_error)
5060 error ("cannot create pointer to reference member %qD", t);
5061 return error_mark_node;
5064 type = build_ptrmem_type (context_for_name_lookup (t),
5066 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
5074 /* Anything not already handled and not a true memory reference
5076 if (TREE_CODE (argtype) != FUNCTION_TYPE
5077 && TREE_CODE (argtype) != METHOD_TYPE
5078 && TREE_CODE (arg) != OFFSET_REF
5079 && !lvalue_or_else (arg, lv_addressof, complain))
5080 return error_mark_node;
5082 if (argtype != error_mark_node)
5083 argtype = build_pointer_type (argtype);
5085 /* In a template, we are processing a non-dependent expression
5086 so we can just form an ADDR_EXPR with the correct type. */
5087 if (processing_template_decl || TREE_CODE (arg) != COMPONENT_REF)
5089 val = build_address (arg);
5090 if (TREE_CODE (arg) == OFFSET_REF)
5091 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
5093 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
5095 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
5097 /* We can only get here with a single static member
5099 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
5100 && DECL_STATIC_FUNCTION_P (fn));
5102 val = build_address (fn);
5103 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
5104 /* Do not lose object's side effects. */
5105 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
5106 TREE_OPERAND (arg, 0), val);
5108 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
5110 if (complain & tf_error)
5111 error ("attempt to take address of bit-field structure member %qD",
5112 TREE_OPERAND (arg, 1));
5113 return error_mark_node;
5117 tree object = TREE_OPERAND (arg, 0);
5118 tree field = TREE_OPERAND (arg, 1);
5119 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5120 (TREE_TYPE (object), decl_type_context (field)));
5121 val = build_address (arg);
5124 if (TREE_CODE (argtype) == POINTER_TYPE
5125 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
5127 build_ptrmemfunc_type (argtype);
5128 val = build_ptrmemfunc (argtype, val, 0,
5129 /*c_cast_p=*/false);
5141 argtype = TREE_TYPE (arg);
5142 return fold_if_not_in_template (build1 (code, argtype, arg));
5145 if (complain & tf_error)
5146 error ("%s", errstring);
5147 return error_mark_node;
5150 /* Hook for the c-common bits that build a unary op. */
5152 build_unary_op (location_t location ATTRIBUTE_UNUSED,
5153 enum tree_code code, tree xarg, int noconvert)
5155 return cp_build_unary_op (code, xarg, noconvert, tf_warning_or_error);
5158 /* Apply unary lvalue-demanding operator CODE to the expression ARG
5159 for certain kinds of expressions which are not really lvalues
5160 but which we can accept as lvalues.
5162 If ARG is not a kind of expression we can handle, return
5166 unary_complex_lvalue (enum tree_code code, tree arg)
5168 /* Inside a template, making these kinds of adjustments is
5169 pointless; we are only concerned with the type of the
5171 if (processing_template_decl)
5174 /* Handle (a, b) used as an "lvalue". */
5175 if (TREE_CODE (arg) == COMPOUND_EXPR)
5177 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 1), 0,
5178 tf_warning_or_error);
5179 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
5180 TREE_OPERAND (arg, 0), real_result);
5183 /* Handle (a ? b : c) used as an "lvalue". */
5184 if (TREE_CODE (arg) == COND_EXPR
5185 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
5186 return rationalize_conditional_expr (code, arg, tf_warning_or_error);
5188 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
5189 if (TREE_CODE (arg) == MODIFY_EXPR
5190 || TREE_CODE (arg) == PREINCREMENT_EXPR
5191 || TREE_CODE (arg) == PREDECREMENT_EXPR)
5193 tree lvalue = TREE_OPERAND (arg, 0);
5194 if (TREE_SIDE_EFFECTS (lvalue))
5196 lvalue = stabilize_reference (lvalue);
5197 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
5198 lvalue, TREE_OPERAND (arg, 1));
5200 return unary_complex_lvalue
5201 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
5204 if (code != ADDR_EXPR)
5207 /* Handle (a = b) used as an "lvalue" for `&'. */
5208 if (TREE_CODE (arg) == MODIFY_EXPR
5209 || TREE_CODE (arg) == INIT_EXPR)
5211 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 0), 0,
5212 tf_warning_or_error);
5213 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
5215 TREE_NO_WARNING (arg) = 1;
5219 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
5220 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
5221 || TREE_CODE (arg) == OFFSET_REF)
5224 /* We permit compiler to make function calls returning
5225 objects of aggregate type look like lvalues. */
5229 if (TREE_CODE (targ) == SAVE_EXPR)
5230 targ = TREE_OPERAND (targ, 0);
5232 if (TREE_CODE (targ) == CALL_EXPR && MAYBE_CLASS_TYPE_P (TREE_TYPE (targ)))
5234 if (TREE_CODE (arg) == SAVE_EXPR)
5237 targ = build_cplus_new (TREE_TYPE (arg), arg);
5238 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
5241 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
5242 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
5243 TREE_OPERAND (targ, 0), current_function_decl, NULL);
5246 /* Don't let anything else be handled specially. */
5250 /* Mark EXP saying that we need to be able to take the
5251 address of it; it should not be allocated in a register.
5252 Value is true if successful.
5254 C++: we do not allow `current_class_ptr' to be addressable. */
5257 cxx_mark_addressable (tree exp)
5262 switch (TREE_CODE (x))
5269 x = TREE_OPERAND (x, 0);
5273 if (x == current_class_ptr)
5275 error ("cannot take the address of %<this%>, which is an rvalue expression");
5276 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
5282 /* Caller should not be trying to mark initialized
5283 constant fields addressable. */
5284 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
5285 || DECL_IN_AGGR_P (x) == 0
5287 || DECL_EXTERNAL (x));
5292 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
5293 && !DECL_ARTIFICIAL (x))
5295 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
5298 ("address of explicit register variable %qD requested", x);
5301 else if (extra_warnings)
5303 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
5305 TREE_ADDRESSABLE (x) = 1;
5309 TREE_ADDRESSABLE (x) = 1;
5313 TREE_ADDRESSABLE (x) = 1;
5317 TREE_ADDRESSABLE (x) = 1;
5318 cxx_mark_addressable (TREE_OPERAND (x, 0));
5326 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
5329 build_x_conditional_expr (tree ifexp, tree op1, tree op2,
5330 tsubst_flags_t complain)
5332 tree orig_ifexp = ifexp;
5333 tree orig_op1 = op1;
5334 tree orig_op2 = op2;
5337 if (processing_template_decl)
5339 /* The standard says that the expression is type-dependent if
5340 IFEXP is type-dependent, even though the eventual type of the
5341 expression doesn't dependent on IFEXP. */
5342 if (type_dependent_expression_p (ifexp)
5343 /* As a GNU extension, the middle operand may be omitted. */
5344 || (op1 && type_dependent_expression_p (op1))
5345 || type_dependent_expression_p (op2))
5346 return build_min_nt (COND_EXPR, ifexp, op1, op2);
5347 ifexp = build_non_dependent_expr (ifexp);
5349 op1 = build_non_dependent_expr (op1);
5350 op2 = build_non_dependent_expr (op2);
5353 expr = build_conditional_expr (ifexp, op1, op2, complain);
5354 if (processing_template_decl && expr != error_mark_node)
5355 return build_min_non_dep (COND_EXPR, expr,
5356 orig_ifexp, orig_op1, orig_op2);
5360 /* Given a list of expressions, return a compound expression
5361 that performs them all and returns the value of the last of them. */
5363 tree build_x_compound_expr_from_list (tree list, const char *msg)
5365 tree expr = TREE_VALUE (list);
5367 if (TREE_CHAIN (list))
5370 permerror (input_location, "%s expression list treated as compound expression", msg);
5372 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
5373 expr = build_x_compound_expr (expr, TREE_VALUE (list),
5374 tf_warning_or_error);
5380 /* Like build_x_compound_expr_from_list, but using a VEC. */
5383 build_x_compound_expr_from_vec (VEC(tree,gc) *vec, const char *msg)
5385 if (VEC_empty (tree, vec))
5387 else if (VEC_length (tree, vec) == 1)
5388 return VEC_index (tree, vec, 0);
5396 permerror (input_location,
5397 "%s expression list treated as compound expression",
5400 expr = VEC_index (tree, vec, 0);
5401 for (ix = 1; VEC_iterate (tree, vec, ix, t); ++ix)
5402 expr = build_x_compound_expr (expr, t, tf_warning_or_error);
5408 /* Handle overloading of the ',' operator when needed. */
5411 build_x_compound_expr (tree op1, tree op2, tsubst_flags_t complain)
5414 tree orig_op1 = op1;
5415 tree orig_op2 = op2;
5417 if (processing_template_decl)
5419 if (type_dependent_expression_p (op1)
5420 || type_dependent_expression_p (op2))
5421 return build_min_nt (COMPOUND_EXPR, op1, op2);
5422 op1 = build_non_dependent_expr (op1);
5423 op2 = build_non_dependent_expr (op2);
5426 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
5427 /*overloaded_p=*/NULL, complain);
5429 result = cp_build_compound_expr (op1, op2, complain);
5431 if (processing_template_decl && result != error_mark_node)
5432 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
5437 /* Like cp_build_compound_expr, but for the c-common bits. */
5440 build_compound_expr (location_t loc ATTRIBUTE_UNUSED, tree lhs, tree rhs)
5442 return cp_build_compound_expr (lhs, rhs, tf_warning_or_error);
5445 /* Build a compound expression. */
5448 cp_build_compound_expr (tree lhs, tree rhs, tsubst_flags_t complain)
5450 lhs = convert_to_void (lhs, "left-hand operand of comma", complain);
5452 if (lhs == error_mark_node || rhs == error_mark_node)
5453 return error_mark_node;
5455 if (TREE_CODE (rhs) == TARGET_EXPR)
5457 /* If the rhs is a TARGET_EXPR, then build the compound
5458 expression inside the target_expr's initializer. This
5459 helps the compiler to eliminate unnecessary temporaries. */
5460 tree init = TREE_OPERAND (rhs, 1);
5462 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
5463 TREE_OPERAND (rhs, 1) = init;
5468 if (type_unknown_p (rhs))
5470 error ("no context to resolve type of %qE", rhs);
5471 return error_mark_node;
5474 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
5477 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
5478 casts away constness. CAST gives the type of cast.
5480 ??? This function warns for casting away any qualifier not just
5481 const. We would like to specify exactly what qualifiers are casted
5486 check_for_casting_away_constness (tree src_type, tree dest_type,
5487 enum tree_code cast)
5489 /* C-style casts are allowed to cast away constness. With
5490 WARN_CAST_QUAL, we still want to issue a warning. */
5491 if (cast == CAST_EXPR && !warn_cast_qual)
5494 if (!casts_away_constness (src_type, dest_type))
5500 warning (OPT_Wcast_qual,
5501 "cast from type %qT to type %qT casts away qualifiers",
5502 src_type, dest_type);
5505 case STATIC_CAST_EXPR:
5506 error ("static_cast from type %qT to type %qT casts away qualifiers",
5507 src_type, dest_type);
5510 case REINTERPRET_CAST_EXPR:
5511 error ("reinterpret_cast from type %qT to type %qT casts away qualifiers",
5512 src_type, dest_type);
5519 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
5520 (another pointer-to-member type in the same hierarchy) and return
5521 the converted expression. If ALLOW_INVERSE_P is permitted, a
5522 pointer-to-derived may be converted to pointer-to-base; otherwise,
5523 only the other direction is permitted. If C_CAST_P is true, this
5524 conversion is taking place as part of a C-style cast. */
5527 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
5530 if (TYPE_PTRMEM_P (type))
5534 if (TREE_CODE (expr) == PTRMEM_CST)
5535 expr = cplus_expand_constant (expr);
5536 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
5537 TYPE_PTRMEM_CLASS_TYPE (type),
5540 if (!integer_zerop (delta))
5542 tree cond, op1, op2;
5544 cond = cp_build_binary_op (input_location,
5547 build_int_cst (TREE_TYPE (expr), -1),
5548 tf_warning_or_error);
5549 op1 = build_nop (ptrdiff_type_node, expr);
5550 op2 = cp_build_binary_op (input_location,
5551 PLUS_EXPR, op1, delta,
5552 tf_warning_or_error);
5554 expr = fold_build3_loc (input_location,
5555 COND_EXPR, ptrdiff_type_node, cond, op1, op2);
5559 return build_nop (type, expr);
5562 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
5563 allow_inverse_p, c_cast_p);
5566 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
5567 a version of EXPR that has TREE_OVERFLOW set if it is set in ORIG.
5568 Otherwise, return EXPR unchanged. */
5571 ignore_overflows (tree expr, tree orig)
5573 if (TREE_CODE (expr) == INTEGER_CST
5574 && CONSTANT_CLASS_P (orig)
5575 && TREE_CODE (orig) != STRING_CST
5576 && TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig))
5578 if (!TREE_OVERFLOW (orig))
5579 /* Ensure constant sharing. */
5580 expr = build_int_cst_wide (TREE_TYPE (expr),
5581 TREE_INT_CST_LOW (expr),
5582 TREE_INT_CST_HIGH (expr));
5585 /* Avoid clobbering a shared constant. */
5586 expr = copy_node (expr);
5587 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
5593 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
5594 this static_cast is being attempted as one of the possible casts
5595 allowed by a C-style cast. (In that case, accessibility of base
5596 classes is not considered, and it is OK to cast away
5597 constness.) Return the result of the cast. *VALID_P is set to
5598 indicate whether or not the cast was valid. */
5601 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
5602 bool *valid_p, tsubst_flags_t complain)
5608 /* Assume the cast is valid. */
5611 intype = TREE_TYPE (expr);
5613 /* Save casted types in the function's used types hash table. */
5614 used_types_insert (type);
5616 /* [expr.static.cast]
5618 An lvalue of type "cv1 B", where B is a class type, can be cast
5619 to type "reference to cv2 D", where D is a class derived (clause
5620 _class.derived_) from B, if a valid standard conversion from
5621 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
5622 same cv-qualification as, or greater cv-qualification than, cv1,
5623 and B is not a virtual base class of D. */
5624 /* We check this case before checking the validity of "TYPE t =
5625 EXPR;" below because for this case:
5628 struct D : public B { D(const B&); };
5630 void f() { static_cast<const D&>(b); }
5632 we want to avoid constructing a new D. The standard is not
5633 completely clear about this issue, but our interpretation is
5634 consistent with other compilers. */
5635 if (TREE_CODE (type) == REFERENCE_TYPE
5636 && CLASS_TYPE_P (TREE_TYPE (type))
5637 && CLASS_TYPE_P (intype)
5638 && (TYPE_REF_IS_RVALUE (type) || real_lvalue_p (expr))
5639 && DERIVED_FROM_P (intype, TREE_TYPE (type))
5640 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
5641 build_pointer_type (TYPE_MAIN_VARIANT
5642 (TREE_TYPE (type))))
5644 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5648 /* There is a standard conversion from "D*" to "B*" even if "B"
5649 is ambiguous or inaccessible. If this is really a
5650 static_cast, then we check both for inaccessibility and
5651 ambiguity. However, if this is a static_cast being performed
5652 because the user wrote a C-style cast, then accessibility is
5654 base = lookup_base (TREE_TYPE (type), intype,
5655 c_cast_p ? ba_unique : ba_check,
5658 /* Convert from "B*" to "D*". This function will check that "B"
5659 is not a virtual base of "D". */
5660 expr = build_base_path (MINUS_EXPR, build_address (expr),
5661 base, /*nonnull=*/false);
5662 /* Convert the pointer to a reference -- but then remember that
5663 there are no expressions with reference type in C++. */
5664 return convert_from_reference (cp_fold_convert (type, expr));
5667 /* "An lvalue of type cv1 T1 can be cast to type rvalue reference to
5668 cv2 T2 if cv2 T2 is reference-compatible with cv1 T1 (8.5.3)." */
5669 if (TREE_CODE (type) == REFERENCE_TYPE
5670 && TYPE_REF_IS_RVALUE (type)
5671 && real_lvalue_p (expr)
5672 && reference_related_p (TREE_TYPE (type), intype)
5673 && (c_cast_p || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5675 expr = build_typed_address (expr, type);
5676 return convert_from_reference (expr);
5681 /* Resolve overloaded address here rather than once in
5682 implicit_conversion and again in the inverse code below. */
5683 if (TYPE_PTRMEMFUNC_P (type) && type_unknown_p (expr))
5685 expr = instantiate_type (type, expr, complain);
5686 intype = TREE_TYPE (expr);
5689 /* [expr.static.cast]
5691 An expression e can be explicitly converted to a type T using a
5692 static_cast of the form static_cast<T>(e) if the declaration T
5693 t(e);" is well-formed, for some invented temporary variable
5695 result = perform_direct_initialization_if_possible (type, expr,
5696 c_cast_p, complain);
5699 result = convert_from_reference (result);
5701 /* Ignore any integer overflow caused by the cast. */
5702 result = ignore_overflows (result, orig);
5704 /* [expr.static.cast]
5706 If T is a reference type, the result is an lvalue; otherwise,
5707 the result is an rvalue. */
5708 if (TREE_CODE (type) != REFERENCE_TYPE)
5709 result = rvalue (result);
5713 /* [expr.static.cast]
5715 Any expression can be explicitly converted to type cv void. */
5716 if (TREE_CODE (type) == VOID_TYPE)
5717 return convert_to_void (expr, /*implicit=*/NULL, complain);
5719 /* [expr.static.cast]
5721 The inverse of any standard conversion sequence (clause _conv_),
5722 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
5723 (_conv.array_), function-to-pointer (_conv.func_), and boolean
5724 (_conv.bool_) conversions, can be performed explicitly using
5725 static_cast subject to the restriction that the explicit
5726 conversion does not cast away constness (_expr.const.cast_), and
5727 the following additional rules for specific cases: */
5728 /* For reference, the conversions not excluded are: integral
5729 promotions, floating point promotion, integral conversions,
5730 floating point conversions, floating-integral conversions,
5731 pointer conversions, and pointer to member conversions. */
5734 A value of integral _or enumeration_ type can be explicitly
5735 converted to an enumeration type. */
5736 /* The effect of all that is that any conversion between any two
5737 types which are integral, floating, or enumeration types can be
5739 if ((INTEGRAL_OR_ENUMERATION_TYPE_P (type)
5740 || SCALAR_FLOAT_TYPE_P (type))
5741 && (INTEGRAL_OR_ENUMERATION_TYPE_P (intype)
5742 || SCALAR_FLOAT_TYPE_P (intype)))
5744 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
5746 /* Ignore any integer overflow caused by the cast. */
5747 expr = ignore_overflows (expr, orig);
5751 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
5752 && CLASS_TYPE_P (TREE_TYPE (type))
5753 && CLASS_TYPE_P (TREE_TYPE (intype))
5754 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
5755 (TREE_TYPE (intype))),
5756 build_pointer_type (TYPE_MAIN_VARIANT
5757 (TREE_TYPE (type)))))
5762 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5763 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
5764 c_cast_p ? ba_unique : ba_check,
5766 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
5769 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5770 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5777 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
5778 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
5780 if (TYPE_PTRMEM_P (type))
5782 t1 = (build_ptrmem_type
5784 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
5785 t2 = (build_ptrmem_type
5787 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
5794 if (can_convert (t1, t2) || can_convert (t2, t1))
5797 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5798 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
5803 /* [expr.static.cast]
5805 An rvalue of type "pointer to cv void" can be explicitly
5806 converted to a pointer to object type. A value of type pointer
5807 to object converted to "pointer to cv void" and back to the
5808 original pointer type will have its original value. */
5809 if (TREE_CODE (intype) == POINTER_TYPE
5810 && VOID_TYPE_P (TREE_TYPE (intype))
5811 && TYPE_PTROB_P (type))
5814 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5815 return build_nop (type, expr);
5819 return error_mark_node;
5822 /* Return an expression representing static_cast<TYPE>(EXPR). */
5825 build_static_cast (tree type, tree expr, tsubst_flags_t complain)
5830 if (type == error_mark_node || expr == error_mark_node)
5831 return error_mark_node;
5833 if (processing_template_decl)
5835 expr = build_min (STATIC_CAST_EXPR, type, expr);
5836 /* We don't know if it will or will not have side effects. */
5837 TREE_SIDE_EFFECTS (expr) = 1;
5838 return convert_from_reference (expr);
5841 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5842 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5843 if (TREE_CODE (type) != REFERENCE_TYPE
5844 && TREE_CODE (expr) == NOP_EXPR
5845 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5846 expr = TREE_OPERAND (expr, 0);
5848 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p,
5853 if (complain & tf_error)
5854 error ("invalid static_cast from type %qT to type %qT",
5855 TREE_TYPE (expr), type);
5856 return error_mark_node;
5859 /* EXPR is an expression with member function or pointer-to-member
5860 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5861 not permitted by ISO C++, but we accept it in some modes. If we
5862 are not in one of those modes, issue a diagnostic. Return the
5863 converted expression. */
5866 convert_member_func_to_ptr (tree type, tree expr)
5871 intype = TREE_TYPE (expr);
5872 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
5873 || TREE_CODE (intype) == METHOD_TYPE);
5875 if (pedantic || warn_pmf2ptr)
5876 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpmf_conversions,
5877 "converting from %qT to %qT", intype, type);
5879 if (TREE_CODE (intype) == METHOD_TYPE)
5880 expr = build_addr_func (expr);
5881 else if (TREE_CODE (expr) == PTRMEM_CST)
5882 expr = build_address (PTRMEM_CST_MEMBER (expr));
5885 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
5886 decl = build_address (decl);
5887 expr = get_member_function_from_ptrfunc (&decl, expr);
5890 return build_nop (type, expr);
5893 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5894 If C_CAST_P is true, this reinterpret cast is being done as part of
5895 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5896 indicate whether or not reinterpret_cast was valid. */
5899 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5900 bool *valid_p, tsubst_flags_t complain)
5904 /* Assume the cast is invalid. */
5908 if (type == error_mark_node || error_operand_p (expr))
5909 return error_mark_node;
5911 intype = TREE_TYPE (expr);
5913 /* Save casted types in the function's used types hash table. */
5914 used_types_insert (type);
5916 /* [expr.reinterpret.cast]
5917 An lvalue expression of type T1 can be cast to the type
5918 "reference to T2" if an expression of type "pointer to T1" can be
5919 explicitly converted to the type "pointer to T2" using a
5920 reinterpret_cast. */
5921 if (TREE_CODE (type) == REFERENCE_TYPE)
5923 if (! real_lvalue_p (expr))
5925 if (complain & tf_error)
5926 error ("invalid cast of an rvalue expression of type "
5929 return error_mark_node;
5932 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5933 "B" are related class types; the reinterpret_cast does not
5934 adjust the pointer. */
5935 if (TYPE_PTR_P (intype)
5936 && (complain & tf_warning)
5937 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5938 COMPARE_BASE | COMPARE_DERIVED)))
5939 warning (0, "casting %qT to %qT does not dereference pointer",
5942 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
5944 if (warn_strict_aliasing > 2)
5945 strict_aliasing_warning (TREE_TYPE (expr), type, expr);
5947 if (expr != error_mark_node)
5948 expr = build_reinterpret_cast_1
5949 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5951 if (expr != error_mark_node)
5952 /* cp_build_indirect_ref isn't right for rvalue refs. */
5953 expr = convert_from_reference (fold_convert (type, expr));
5957 /* As a G++ extension, we consider conversions from member
5958 functions, and pointers to member functions to
5959 pointer-to-function and pointer-to-void types. If
5960 -Wno-pmf-conversions has not been specified,
5961 convert_member_func_to_ptr will issue an error message. */
5962 if ((TYPE_PTRMEMFUNC_P (intype)
5963 || TREE_CODE (intype) == METHOD_TYPE)
5964 && TYPE_PTR_P (type)
5965 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5966 || VOID_TYPE_P (TREE_TYPE (type))))
5967 return convert_member_func_to_ptr (type, expr);
5969 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5970 array-to-pointer, and function-to-pointer conversions are
5972 expr = decay_conversion (expr);
5974 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5975 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5976 if (TREE_CODE (expr) == NOP_EXPR
5977 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5978 expr = TREE_OPERAND (expr, 0);
5980 if (error_operand_p (expr))
5981 return error_mark_node;
5983 intype = TREE_TYPE (expr);
5985 /* [expr.reinterpret.cast]
5986 A pointer can be converted to any integral type large enough to
5988 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5990 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5992 if (complain & tf_error)
5993 permerror (input_location, "cast from %qT to %qT loses precision",
5996 return error_mark_node;
5999 /* [expr.reinterpret.cast]
6000 A value of integral or enumeration type can be explicitly
6001 converted to a pointer. */
6002 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
6005 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
6006 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
6007 return fold_if_not_in_template (build_nop (type, expr));
6008 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
6009 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
6014 check_for_casting_away_constness (intype, type, REINTERPRET_CAST_EXPR);
6015 /* Warn about possible alignment problems. */
6016 if (STRICT_ALIGNMENT && warn_cast_align
6017 && (complain & tf_warning)
6018 && !VOID_TYPE_P (type)
6019 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
6020 && COMPLETE_TYPE_P (TREE_TYPE (type))
6021 && COMPLETE_TYPE_P (TREE_TYPE (intype))
6022 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
6023 warning (OPT_Wcast_align, "cast from %qT to %qT "
6024 "increases required alignment of target type", intype, type);
6026 /* We need to strip nops here, because the front end likes to
6027 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
6029 if (warn_strict_aliasing <= 2)
6030 strict_aliasing_warning (intype, type, sexpr);
6032 return fold_if_not_in_template (build_nop (type, expr));
6034 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
6035 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
6037 if (pedantic && (complain & tf_warning))
6038 /* Only issue a warning, as we have always supported this
6039 where possible, and it is necessary in some cases. DR 195
6040 addresses this issue, but as of 2004/10/26 is still in
6042 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
6043 return fold_if_not_in_template (build_nop (type, expr));
6045 else if (TREE_CODE (type) == VECTOR_TYPE)
6046 return fold_if_not_in_template (convert_to_vector (type, expr));
6047 else if (TREE_CODE (intype) == VECTOR_TYPE
6048 && INTEGRAL_OR_ENUMERATION_TYPE_P (type))
6049 return fold_if_not_in_template (convert_to_integer (type, expr));
6054 if (complain & tf_error)
6055 error ("invalid cast from type %qT to type %qT", intype, type);
6056 return error_mark_node;
6059 return cp_convert (type, expr);
6063 build_reinterpret_cast (tree type, tree expr, tsubst_flags_t complain)
6065 if (type == error_mark_node || expr == error_mark_node)
6066 return error_mark_node;
6068 if (processing_template_decl)
6070 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
6072 if (!TREE_SIDE_EFFECTS (t)
6073 && type_dependent_expression_p (expr))
6074 /* There might turn out to be side effects inside expr. */
6075 TREE_SIDE_EFFECTS (t) = 1;
6076 return convert_from_reference (t);
6079 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
6080 /*valid_p=*/NULL, complain);
6083 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
6084 return an appropriate expression. Otherwise, return
6085 error_mark_node. If the cast is not valid, and COMPLAIN is true,
6086 then a diagnostic will be issued. If VALID_P is non-NULL, we are
6087 performing a C-style cast, its value upon return will indicate
6088 whether or not the conversion succeeded. */
6091 build_const_cast_1 (tree dst_type, tree expr, bool complain,
6095 tree reference_type;
6097 /* Callers are responsible for handling error_mark_node as a
6098 destination type. */
6099 gcc_assert (dst_type != error_mark_node);
6100 /* In a template, callers should be building syntactic
6101 representations of casts, not using this machinery. */
6102 gcc_assert (!processing_template_decl);
6104 /* Assume the conversion is invalid. */
6108 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
6111 error ("invalid use of const_cast with type %qT, "
6112 "which is not a pointer, "
6113 "reference, nor a pointer-to-data-member type", dst_type);
6114 return error_mark_node;
6117 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
6120 error ("invalid use of const_cast with type %qT, which is a pointer "
6121 "or reference to a function type", dst_type);
6122 return error_mark_node;
6125 /* Save casted types in the function's used types hash table. */
6126 used_types_insert (dst_type);
6128 src_type = TREE_TYPE (expr);
6129 /* Expressions do not really have reference types. */
6130 if (TREE_CODE (src_type) == REFERENCE_TYPE)
6131 src_type = TREE_TYPE (src_type);
6133 /* [expr.const.cast]
6135 An lvalue of type T1 can be explicitly converted to an lvalue of
6136 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
6137 types) if a pointer to T1 can be explicitly converted to the type
6138 pointer to T2 using a const_cast. */
6139 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
6141 reference_type = dst_type;
6142 if (! real_lvalue_p (expr))
6145 error ("invalid const_cast of an rvalue of type %qT to type %qT",
6146 src_type, dst_type);
6147 return error_mark_node;
6149 dst_type = build_pointer_type (TREE_TYPE (dst_type));
6150 src_type = build_pointer_type (src_type);
6154 reference_type = NULL_TREE;
6155 /* If the destination type is not a reference type, the
6156 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
6157 conversions are performed. */
6158 src_type = type_decays_to (src_type);
6159 if (src_type == error_mark_node)
6160 return error_mark_node;
6163 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
6164 && comp_ptr_ttypes_const (dst_type, src_type))
6169 /* This cast is actually a C-style cast. Issue a warning if
6170 the user is making a potentially unsafe cast. */
6171 check_for_casting_away_constness (src_type, dst_type, CAST_EXPR);
6175 expr = cp_build_unary_op (ADDR_EXPR, expr, 0,
6176 complain? tf_warning_or_error : tf_none);
6177 expr = build_nop (reference_type, expr);
6178 return convert_from_reference (expr);
6182 expr = decay_conversion (expr);
6183 /* build_c_cast puts on a NOP_EXPR to make the result not an
6184 lvalue. Strip such NOP_EXPRs if VALUE is being used in
6185 non-lvalue context. */
6186 if (TREE_CODE (expr) == NOP_EXPR
6187 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
6188 expr = TREE_OPERAND (expr, 0);
6189 return build_nop (dst_type, expr);
6194 error ("invalid const_cast from type %qT to type %qT",
6195 src_type, dst_type);
6196 return error_mark_node;
6200 build_const_cast (tree type, tree expr, tsubst_flags_t complain)
6202 if (type == error_mark_node || error_operand_p (expr))
6203 return error_mark_node;
6205 if (processing_template_decl)
6207 tree t = build_min (CONST_CAST_EXPR, type, expr);
6209 if (!TREE_SIDE_EFFECTS (t)
6210 && type_dependent_expression_p (expr))
6211 /* There might turn out to be side effects inside expr. */
6212 TREE_SIDE_EFFECTS (t) = 1;
6213 return convert_from_reference (t);
6216 return build_const_cast_1 (type, expr, complain & tf_error,
6220 /* Like cp_build_c_cast, but for the c-common bits. */
6223 build_c_cast (location_t loc ATTRIBUTE_UNUSED, tree type, tree expr)
6225 return cp_build_c_cast (type, expr, tf_warning_or_error);
6228 /* Build an expression representing an explicit C-style cast to type
6229 TYPE of expression EXPR. */
6232 cp_build_c_cast (tree type, tree expr, tsubst_flags_t complain)
6238 if (type == error_mark_node || error_operand_p (expr))
6239 return error_mark_node;
6241 if (processing_template_decl)
6243 tree t = build_min (CAST_EXPR, type,
6244 tree_cons (NULL_TREE, value, NULL_TREE));
6245 /* We don't know if it will or will not have side effects. */
6246 TREE_SIDE_EFFECTS (t) = 1;
6247 return convert_from_reference (t);
6250 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
6251 'Class') should always be retained, because this information aids
6252 in method lookup. */
6253 if (objc_is_object_ptr (type)
6254 && objc_is_object_ptr (TREE_TYPE (expr)))
6255 return build_nop (type, expr);
6257 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6258 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
6259 if (TREE_CODE (type) != REFERENCE_TYPE
6260 && TREE_CODE (value) == NOP_EXPR
6261 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
6262 value = TREE_OPERAND (value, 0);
6264 if (TREE_CODE (type) == ARRAY_TYPE)
6266 /* Allow casting from T1* to T2[] because Cfront allows it.
6267 NIHCL uses it. It is not valid ISO C++ however. */
6268 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
6270 if (complain & tf_error)
6271 permerror (input_location, "ISO C++ forbids casting to an array type %qT", type);
6273 return error_mark_node;
6274 type = build_pointer_type (TREE_TYPE (type));
6278 if (complain & tf_error)
6279 error ("ISO C++ forbids casting to an array type %qT", type);
6280 return error_mark_node;
6284 if (TREE_CODE (type) == FUNCTION_TYPE
6285 || TREE_CODE (type) == METHOD_TYPE)
6287 if (complain & tf_error)
6288 error ("invalid cast to function type %qT", type);
6289 return error_mark_node;
6292 if (TREE_CODE (type) == POINTER_TYPE
6293 && TREE_CODE (TREE_TYPE (value)) == INTEGER_TYPE
6294 /* Casting to an integer of smaller size is an error detected elsewhere. */
6295 && TYPE_PRECISION (type) > TYPE_PRECISION (TREE_TYPE (value))
6296 /* Don't warn about converting any constant. */
6297 && !TREE_CONSTANT (value))
6298 warning_at (input_location, OPT_Wint_to_pointer_cast,
6299 "cast to pointer from integer of different size");
6301 /* A C-style cast can be a const_cast. */
6302 result = build_const_cast_1 (type, value, /*complain=*/false,
6307 /* Or a static cast. */
6308 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
6309 &valid_p, complain);
6310 /* Or a reinterpret_cast. */
6312 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
6313 &valid_p, complain);
6314 /* The static_cast or reinterpret_cast may be followed by a
6317 /* A valid cast may result in errors if, for example, a
6318 conversion to am ambiguous base class is required. */
6319 && !error_operand_p (result))
6323 /* Non-class rvalues always have cv-unqualified type. */
6324 if (!CLASS_TYPE_P (type))
6325 type = TYPE_MAIN_VARIANT (type);
6326 result_type = TREE_TYPE (result);
6327 if (!CLASS_TYPE_P (result_type))
6328 result_type = TYPE_MAIN_VARIANT (result_type);
6329 /* If the type of RESULT does not match TYPE, perform a
6330 const_cast to make it match. If the static_cast or
6331 reinterpret_cast succeeded, we will differ by at most
6332 cv-qualification, so the follow-on const_cast is guaranteed
6334 if (!same_type_p (non_reference (type), non_reference (result_type)))
6336 result = build_const_cast_1 (type, result, false, &valid_p);
6337 gcc_assert (valid_p);
6342 return error_mark_node;
6345 /* For use from the C common bits. */
6347 build_modify_expr (location_t location ATTRIBUTE_UNUSED,
6348 tree lhs, tree lhs_origtype ATTRIBUTE_UNUSED,
6349 enum tree_code modifycode,
6350 location_t rhs_location ATTRIBUTE_UNUSED, tree rhs,
6351 tree rhs_origtype ATTRIBUTE_UNUSED)
6353 return cp_build_modify_expr (lhs, modifycode, rhs, tf_warning_or_error);
6356 /* Build an assignment expression of lvalue LHS from value RHS.
6357 MODIFYCODE is the code for a binary operator that we use
6358 to combine the old value of LHS with RHS to get the new value.
6359 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
6361 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
6364 cp_build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6365 tsubst_flags_t complain)
6369 tree lhstype = TREE_TYPE (lhs);
6370 tree olhstype = lhstype;
6371 bool plain_assign = (modifycode == NOP_EXPR);
6373 /* Avoid duplicate error messages from operands that had errors. */
6374 if (error_operand_p (lhs) || error_operand_p (rhs))
6375 return error_mark_node;
6377 /* Handle control structure constructs used as "lvalues". */
6378 switch (TREE_CODE (lhs))
6380 /* Handle --foo = 5; as these are valid constructs in C++. */
6381 case PREDECREMENT_EXPR:
6382 case PREINCREMENT_EXPR:
6383 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
6384 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
6385 stabilize_reference (TREE_OPERAND (lhs, 0)),
6386 TREE_OPERAND (lhs, 1));
6387 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0),
6388 modifycode, rhs, complain);
6389 if (newrhs == error_mark_node)
6390 return error_mark_node;
6391 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
6393 /* Handle (a, b) used as an "lvalue". */
6395 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6396 modifycode, rhs, complain);
6397 if (newrhs == error_mark_node)
6398 return error_mark_node;
6399 return build2 (COMPOUND_EXPR, lhstype,
6400 TREE_OPERAND (lhs, 0), newrhs);
6403 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
6404 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
6405 stabilize_reference (TREE_OPERAND (lhs, 0)),
6406 TREE_OPERAND (lhs, 1));
6407 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs,
6409 if (newrhs == error_mark_node)
6410 return error_mark_node;
6411 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
6415 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
6416 when neither operand has side-effects. */
6417 if (!lvalue_or_else (lhs, lv_assign, complain))
6418 return error_mark_node;
6420 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
6421 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
6423 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
6424 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
6426 TREE_OPERAND (lhs, 0),
6427 TREE_OPERAND (lhs, 1)),
6428 TREE_OPERAND (lhs, 0),
6429 TREE_OPERAND (lhs, 1));
6432 /* Handle (a ? b : c) used as an "lvalue". */
6435 /* Produce (a ? (b = rhs) : (c = rhs))
6436 except that the RHS goes through a save-expr
6437 so the code to compute it is only emitted once. */
6439 tree preeval = NULL_TREE;
6441 if (VOID_TYPE_P (TREE_TYPE (rhs)))
6443 if (complain & tf_error)
6444 error ("void value not ignored as it ought to be");
6445 return error_mark_node;
6448 rhs = stabilize_expr (rhs, &preeval);
6450 /* Check this here to avoid odd errors when trying to convert
6451 a throw to the type of the COND_EXPR. */
6452 if (!lvalue_or_else (lhs, lv_assign, complain))
6453 return error_mark_node;
6455 cond = build_conditional_expr
6456 (TREE_OPERAND (lhs, 0),
6457 cp_build_modify_expr (TREE_OPERAND (lhs, 1),
6458 modifycode, rhs, complain),
6459 cp_build_modify_expr (TREE_OPERAND (lhs, 2),
6460 modifycode, rhs, complain),
6463 if (cond == error_mark_node)
6465 /* Make sure the code to compute the rhs comes out
6466 before the split. */
6468 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
6476 if (modifycode == INIT_EXPR)
6478 if (BRACE_ENCLOSED_INITIALIZER_P (rhs))
6479 /* Do the default thing. */;
6480 else if (TREE_CODE (rhs) == CONSTRUCTOR)
6482 /* Compound literal. */
6483 if (! same_type_p (TREE_TYPE (rhs), lhstype))
6484 /* Call convert to generate an error; see PR 11063. */
6485 rhs = convert (lhstype, rhs);
6486 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
6487 TREE_SIDE_EFFECTS (result) = 1;
6490 else if (! MAYBE_CLASS_TYPE_P (lhstype))
6491 /* Do the default thing. */;
6494 VEC(tree,gc) *rhs_vec = make_tree_vector_single (rhs);
6495 result = build_special_member_call (lhs, complete_ctor_identifier,
6496 &rhs_vec, lhstype, LOOKUP_NORMAL,
6498 release_tree_vector (rhs_vec);
6499 if (result == NULL_TREE)
6500 return error_mark_node;
6506 lhs = require_complete_type (lhs);
6507 if (lhs == error_mark_node)
6508 return error_mark_node;
6510 if (modifycode == NOP_EXPR)
6512 /* `operator=' is not an inheritable operator. */
6513 if (! MAYBE_CLASS_TYPE_P (lhstype))
6514 /* Do the default thing. */;
6517 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
6518 lhs, rhs, make_node (NOP_EXPR),
6519 /*overloaded_p=*/NULL,
6521 if (result == NULL_TREE)
6522 return error_mark_node;
6529 /* A binary op has been requested. Combine the old LHS
6530 value with the RHS producing the value we should actually
6531 store into the LHS. */
6532 gcc_assert (!((TREE_CODE (lhstype) == REFERENCE_TYPE
6533 && MAYBE_CLASS_TYPE_P (TREE_TYPE (lhstype)))
6534 || MAYBE_CLASS_TYPE_P (lhstype)));
6536 lhs = stabilize_reference (lhs);
6537 newrhs = cp_build_binary_op (input_location,
6538 modifycode, lhs, rhs,
6540 if (newrhs == error_mark_node)
6542 if (complain & tf_error)
6543 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
6544 TREE_TYPE (lhs), TREE_TYPE (rhs));
6545 return error_mark_node;
6548 /* Now it looks like a plain assignment. */
6549 modifycode = NOP_EXPR;
6551 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
6552 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
6555 /* The left-hand side must be an lvalue. */
6556 if (!lvalue_or_else (lhs, lv_assign, complain))
6557 return error_mark_node;
6559 /* Warn about modifying something that is `const'. Don't warn if
6560 this is initialization. */
6561 if (modifycode != INIT_EXPR
6562 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
6563 /* Functions are not modifiable, even though they are
6565 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
6566 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
6567 /* If it's an aggregate and any field is const, then it is
6568 effectively const. */
6569 || (CLASS_TYPE_P (lhstype)
6570 && C_TYPE_FIELDS_READONLY (lhstype))))
6572 if (complain & tf_error)
6573 readonly_error (lhs, REK_ASSIGNMENT);
6575 return error_mark_node;
6578 /* If storing into a structure or union member, it may have been given a
6579 lowered bitfield type. We need to convert to the declared type first,
6580 so retrieve it now. */
6582 olhstype = unlowered_expr_type (lhs);
6584 /* Convert new value to destination type. */
6586 if (TREE_CODE (lhstype) == ARRAY_TYPE)
6590 if (BRACE_ENCLOSED_INITIALIZER_P (newrhs))
6592 if (check_array_initializer (lhs, lhstype, newrhs))
6593 return error_mark_node;
6594 newrhs = digest_init (lhstype, newrhs);
6597 else if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
6598 TYPE_MAIN_VARIANT (TREE_TYPE (newrhs))))
6600 if (complain & tf_error)
6601 error ("incompatible types in assignment of %qT to %qT",
6602 TREE_TYPE (rhs), lhstype);
6603 return error_mark_node;
6606 /* Allow array assignment in compiler-generated code. */
6607 else if (!current_function_decl
6608 || !DECL_ARTIFICIAL (current_function_decl))
6610 /* This routine is used for both initialization and assignment.
6611 Make sure the diagnostic message differentiates the context. */
6612 if (complain & tf_error)
6614 if (modifycode == INIT_EXPR)
6615 error ("array used as initializer");
6617 error ("invalid array assignment");
6619 return error_mark_node;
6622 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
6623 ? 1 + (modifycode != INIT_EXPR): 0;
6624 return build_vec_init (lhs, NULL_TREE, newrhs,
6625 /*explicit_value_init_p=*/false,
6626 from_array, complain);
6629 if (modifycode == INIT_EXPR)
6630 /* Calls with INIT_EXPR are all direct-initialization, so don't set
6631 LOOKUP_ONLYCONVERTING. */
6632 newrhs = convert_for_initialization (lhs, olhstype, newrhs, LOOKUP_NORMAL,
6633 "initialization", NULL_TREE, 0,
6636 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
6637 NULL_TREE, 0, complain, LOOKUP_IMPLICIT);
6639 if (!same_type_p (lhstype, olhstype))
6640 newrhs = cp_convert_and_check (lhstype, newrhs);
6642 if (modifycode != INIT_EXPR)
6644 if (TREE_CODE (newrhs) == CALL_EXPR
6645 && TYPE_NEEDS_CONSTRUCTING (lhstype))
6646 newrhs = build_cplus_new (lhstype, newrhs);
6648 /* Can't initialize directly from a TARGET_EXPR, since that would
6649 cause the lhs to be constructed twice, and possibly result in
6650 accidental self-initialization. So we force the TARGET_EXPR to be
6651 expanded without a target. */
6652 if (TREE_CODE (newrhs) == TARGET_EXPR)
6653 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
6654 TREE_OPERAND (newrhs, 0));
6657 if (newrhs == error_mark_node)
6658 return error_mark_node;
6660 if (c_dialect_objc () && flag_objc_gc)
6662 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
6668 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
6669 lhstype, lhs, newrhs);
6671 TREE_SIDE_EFFECTS (result) = 1;
6673 TREE_NO_WARNING (result) = 1;
6679 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6680 tsubst_flags_t complain)
6682 if (processing_template_decl)
6683 return build_min_nt (MODOP_EXPR, lhs,
6684 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
6686 if (modifycode != NOP_EXPR)
6688 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
6689 make_node (modifycode),
6690 /*overloaded_p=*/NULL,
6694 TREE_NO_WARNING (rval) = 1;
6698 return cp_build_modify_expr (lhs, modifycode, rhs, complain);
6701 /* Helper function for get_delta_difference which assumes FROM is a base
6702 class of TO. Returns a delta for the conversion of pointer-to-member
6703 of FROM to pointer-to-member of TO. If the conversion is invalid,
6704 returns zero. If FROM is not a base class of TO, returns NULL_TREE.
6705 If C_CAST_P is true, this conversion is taking place as part of a C-style
6709 get_delta_difference_1 (tree from, tree to, bool c_cast_p)
6714 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
6715 if (kind == bk_inaccessible || kind == bk_ambig)
6717 error (" in pointer to member function conversion");
6718 return size_zero_node;
6722 if (kind != bk_via_virtual)
6723 return BINFO_OFFSET (binfo);
6725 /* FROM is a virtual base class of TO. Issue an error or warning
6726 depending on whether or not this is a reinterpret cast. */
6728 error ("pointer to member conversion via virtual base %qT",
6729 BINFO_TYPE (binfo_from_vbase (binfo)));
6731 return size_zero_node;
6738 /* Get difference in deltas for different pointer to member function
6739 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
6740 the conversion is invalid, the constant is zero. If
6741 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
6742 If C_CAST_P is true this conversion is taking place as part of a
6745 Note that the naming of FROM and TO is kind of backwards; the return
6746 value is what we add to a TO in order to get a FROM. They are named
6747 this way because we call this function to find out how to convert from
6748 a pointer to member of FROM to a pointer to member of TO. */
6751 get_delta_difference (tree from, tree to,
6752 bool allow_inverse_p,
6757 if (same_type_ignoring_top_level_qualifiers_p (from, to))
6758 /* Pointer to member of incomplete class is permitted*/
6759 result = size_zero_node;
6761 result = get_delta_difference_1 (from, to, c_cast_p);
6765 if (!allow_inverse_p)
6767 error_not_base_type (from, to);
6768 error (" in pointer to member conversion");
6769 result = size_zero_node;
6773 result = get_delta_difference_1 (to, from, c_cast_p);
6776 result = size_diffop_loc (input_location,
6777 size_zero_node, result);
6780 error_not_base_type (from, to);
6781 error (" in pointer to member conversion");
6782 result = size_zero_node;
6787 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
6791 /* Return a constructor for the pointer-to-member-function TYPE using
6792 the other components as specified. */
6795 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
6800 VEC(constructor_elt, gc) *v;
6802 /* Pull the FIELD_DECLs out of the type. */
6803 pfn_field = TYPE_FIELDS (type);
6804 delta_field = TREE_CHAIN (pfn_field);
6806 /* Make sure DELTA has the type we want. */
6807 delta = convert_and_check (delta_type_node, delta);
6809 /* Convert to the correct target type if necessary. */
6810 pfn = fold_convert (TREE_TYPE (pfn_field), pfn);
6812 /* Finish creating the initializer. */
6813 v = VEC_alloc(constructor_elt, gc, 2);
6814 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
6815 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
6816 u = build_constructor (type, v);
6817 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
6818 TREE_STATIC (u) = (TREE_CONSTANT (u)
6819 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
6821 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
6826 /* Build a constructor for a pointer to member function. It can be
6827 used to initialize global variables, local variable, or used
6828 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
6831 If FORCE is nonzero, then force this conversion, even if
6832 we would rather not do it. Usually set when using an explicit
6833 cast. A C-style cast is being processed iff C_CAST_P is true.
6835 Return error_mark_node, if something goes wrong. */
6838 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
6844 if (error_operand_p (pfn))
6845 return error_mark_node;
6847 pfn_type = TREE_TYPE (pfn);
6848 to_type = build_ptrmemfunc_type (type);
6850 /* Handle multiple conversions of pointer to member functions. */
6851 if (TYPE_PTRMEMFUNC_P (pfn_type))
6853 tree delta = NULL_TREE;
6854 tree npfn = NULL_TREE;
6858 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
6859 error ("invalid conversion to type %qT from type %qT",
6862 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
6863 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
6867 /* We don't have to do any conversion to convert a
6868 pointer-to-member to its own type. But, we don't want to
6869 just return a PTRMEM_CST if there's an explicit cast; that
6870 cast should make the expression an invalid template argument. */
6871 if (TREE_CODE (pfn) != PTRMEM_CST)
6873 if (same_type_p (to_type, pfn_type))
6875 else if (integer_zerop (n))
6876 return build_reinterpret_cast (to_type, pfn,
6877 tf_warning_or_error);
6880 if (TREE_SIDE_EFFECTS (pfn))
6881 pfn = save_expr (pfn);
6883 /* Obtain the function pointer and the current DELTA. */
6884 if (TREE_CODE (pfn) == PTRMEM_CST)
6885 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
6888 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
6889 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
6892 /* Just adjust the DELTA field. */
6893 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6894 (TREE_TYPE (delta), ptrdiff_type_node));
6895 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
6896 n = cp_build_binary_op (input_location,
6897 LSHIFT_EXPR, n, integer_one_node,
6898 tf_warning_or_error);
6899 delta = cp_build_binary_op (input_location,
6900 PLUS_EXPR, delta, n, tf_warning_or_error);
6901 return build_ptrmemfunc1 (to_type, delta, npfn);
6904 /* Handle null pointer to member function conversions. */
6905 if (integer_zerop (pfn))
6907 pfn = build_c_cast (input_location, type, integer_zero_node);
6908 return build_ptrmemfunc1 (to_type,
6913 if (type_unknown_p (pfn))
6914 return instantiate_type (type, pfn, tf_warning_or_error);
6916 fn = TREE_OPERAND (pfn, 0);
6917 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
6918 /* In a template, we will have preserved the
6920 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
6921 return make_ptrmem_cst (to_type, fn);
6924 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
6927 ??? There is no consistency as to the types returned for the above
6928 values. Some code acts as if it were a sizetype and some as if it were
6929 integer_type_node. */
6932 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
6934 tree type = TREE_TYPE (cst);
6935 tree fn = PTRMEM_CST_MEMBER (cst);
6936 tree ptr_class, fn_class;
6938 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6940 /* The class that the function belongs to. */
6941 fn_class = DECL_CONTEXT (fn);
6943 /* The class that we're creating a pointer to member of. */
6944 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
6946 /* First, calculate the adjustment to the function's class. */
6947 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
6950 if (!DECL_VIRTUAL_P (fn))
6951 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
6954 /* If we're dealing with a virtual function, we have to adjust 'this'
6955 again, to point to the base which provides the vtable entry for
6956 fn; the call will do the opposite adjustment. */
6957 tree orig_class = DECL_CONTEXT (fn);
6958 tree binfo = binfo_or_else (orig_class, fn_class);
6959 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6960 *delta, BINFO_OFFSET (binfo));
6961 *delta = fold_if_not_in_template (*delta);
6963 /* We set PFN to the vtable offset at which the function can be
6964 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6965 case delta is shifted left, and then incremented). */
6966 *pfn = DECL_VINDEX (fn);
6967 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
6968 TYPE_SIZE_UNIT (vtable_entry_type));
6969 *pfn = fold_if_not_in_template (*pfn);
6971 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
6973 case ptrmemfunc_vbit_in_pfn:
6974 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6976 *pfn = fold_if_not_in_template (*pfn);
6979 case ptrmemfunc_vbit_in_delta:
6980 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6981 *delta, integer_one_node);
6982 *delta = fold_if_not_in_template (*delta);
6983 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6984 *delta, integer_one_node);
6985 *delta = fold_if_not_in_template (*delta);
6992 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6993 *pfn = fold_if_not_in_template (*pfn);
6997 /* Return an expression for PFN from the pointer-to-member function
7001 pfn_from_ptrmemfunc (tree t)
7003 if (TREE_CODE (t) == PTRMEM_CST)
7008 expand_ptrmemfunc_cst (t, &delta, &pfn);
7013 return build_ptrmemfunc_access_expr (t, pfn_identifier);
7016 /* Return an expression for DELTA from the pointer-to-member function
7020 delta_from_ptrmemfunc (tree t)
7022 if (TREE_CODE (t) == PTRMEM_CST)
7027 expand_ptrmemfunc_cst (t, &delta, &pfn);
7032 return build_ptrmemfunc_access_expr (t, delta_identifier);
7035 /* Convert value RHS to type TYPE as preparation for an assignment to
7036 an lvalue of type TYPE. ERRTYPE is a string to use in error
7037 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
7038 are doing the conversion in order to pass the PARMNUMth argument of
7042 convert_for_assignment (tree type, tree rhs,
7043 const char *errtype, tree fndecl, int parmnum,
7044 tsubst_flags_t complain, int flags)
7047 enum tree_code coder;
7049 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
7050 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
7051 rhs = TREE_OPERAND (rhs, 0);
7053 rhstype = TREE_TYPE (rhs);
7054 coder = TREE_CODE (rhstype);
7056 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
7057 && vector_types_convertible_p (type, rhstype, true))
7058 return convert (type, rhs);
7060 if (rhs == error_mark_node || rhstype == error_mark_node)
7061 return error_mark_node;
7062 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
7063 return error_mark_node;
7065 /* The RHS of an assignment cannot have void type. */
7066 if (coder == VOID_TYPE)
7068 if (complain & tf_error)
7069 error ("void value not ignored as it ought to be");
7070 return error_mark_node;
7073 /* Simplify the RHS if possible. */
7074 if (TREE_CODE (rhs) == CONST_DECL)
7075 rhs = DECL_INITIAL (rhs);
7077 if (c_dialect_objc ())
7080 tree rname = fndecl;
7082 if (!strcmp (errtype, "assignment"))
7084 else if (!strcmp (errtype, "initialization"))
7088 tree selector = objc_message_selector ();
7092 if (selector && parmno > 1)
7099 if (objc_compare_types (type, rhstype, parmno, rname))
7100 return convert (type, rhs);
7105 The expression is implicitly converted (clause _conv_) to the
7106 cv-unqualified type of the left operand.
7108 We allow bad conversions here because by the time we get to this point
7109 we are committed to doing the conversion. If we end up doing a bad
7110 conversion, convert_like will complain. */
7111 if (!can_convert_arg_bad (type, rhstype, rhs, flags))
7113 /* When -Wno-pmf-conversions is use, we just silently allow
7114 conversions from pointers-to-members to plain pointers. If
7115 the conversion doesn't work, cp_convert will complain. */
7117 && TYPE_PTR_P (type)
7118 && TYPE_PTRMEMFUNC_P (rhstype))
7119 rhs = cp_convert (strip_top_quals (type), rhs);
7122 if (complain & tf_error)
7124 /* If the right-hand side has unknown type, then it is an
7125 overloaded function. Call instantiate_type to get error
7127 if (rhstype == unknown_type_node)
7128 instantiate_type (type, rhs, tf_warning_or_error);
7130 error ("cannot convert %qT to %qT for argument %qP to %qD",
7131 rhstype, type, parmnum, fndecl);
7133 error ("cannot convert %qT to %qT in %s", rhstype, type,
7136 return error_mark_node;
7139 if (warn_missing_format_attribute)
7141 const enum tree_code codel = TREE_CODE (type);
7142 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
7144 && check_missing_format_attribute (type, rhstype)
7145 && (complain & tf_warning))
7146 warning (OPT_Wmissing_format_attribute,
7147 "%s might be a candidate for a format attribute",
7151 /* If -Wparentheses, warn about a = b = c when a has type bool and b
7153 if (warn_parentheses
7154 && TREE_CODE (type) == BOOLEAN_TYPE
7155 && TREE_CODE (rhs) == MODIFY_EXPR
7156 && !TREE_NO_WARNING (rhs)
7157 && TREE_CODE (TREE_TYPE (rhs)) != BOOLEAN_TYPE
7158 && (complain & tf_warning))
7160 location_t loc = EXPR_HAS_LOCATION (rhs)
7161 ? EXPR_LOCATION (rhs) : input_location;
7163 warning_at (loc, OPT_Wparentheses,
7164 "suggest parentheses around assignment used as truth value");
7165 TREE_NO_WARNING (rhs) = 1;
7168 return perform_implicit_conversion_flags (strip_top_quals (type), rhs,
7172 /* Convert RHS to be of type TYPE.
7173 If EXP is nonzero, it is the target of the initialization.
7174 ERRTYPE is a string to use in error messages.
7176 Two major differences between the behavior of
7177 `convert_for_assignment' and `convert_for_initialization'
7178 are that references are bashed in the former, while
7179 copied in the latter, and aggregates are assigned in
7180 the former (operator=) while initialized in the
7183 If using constructor make sure no conversion operator exists, if one does
7184 exist, an ambiguity exists.
7186 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
7189 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
7190 const char *errtype, tree fndecl, int parmnum,
7191 tsubst_flags_t complain)
7193 enum tree_code codel = TREE_CODE (type);
7195 enum tree_code coder;
7197 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
7198 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
7199 if (TREE_CODE (rhs) == NOP_EXPR
7200 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
7201 && codel != REFERENCE_TYPE)
7202 rhs = TREE_OPERAND (rhs, 0);
7204 if (type == error_mark_node
7205 || rhs == error_mark_node
7206 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
7207 return error_mark_node;
7209 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
7210 && TREE_CODE (type) != ARRAY_TYPE
7211 && (TREE_CODE (type) != REFERENCE_TYPE
7212 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
7213 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
7214 && (TREE_CODE (type) != REFERENCE_TYPE
7215 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
7216 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
7217 rhs = decay_conversion (rhs);
7219 rhstype = TREE_TYPE (rhs);
7220 coder = TREE_CODE (rhstype);
7222 if (coder == ERROR_MARK)
7223 return error_mark_node;
7225 /* We accept references to incomplete types, so we can
7226 return here before checking if RHS is of complete type. */
7228 if (codel == REFERENCE_TYPE)
7230 /* This should eventually happen in convert_arguments. */
7231 int savew = 0, savee = 0;
7234 savew = warningcount, savee = errorcount;
7235 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
7236 /*cleanup=*/NULL, complain);
7239 if (warningcount > savew)
7240 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
7241 else if (errorcount > savee)
7242 error ("in passing argument %P of %q+D", parmnum, fndecl);
7248 exp = require_complete_type (exp);
7249 if (exp == error_mark_node)
7250 return error_mark_node;
7252 rhstype = non_reference (rhstype);
7254 type = complete_type (type);
7256 if (DIRECT_INIT_EXPR_P (type, rhs))
7257 /* Don't try to do copy-initialization if we already have
7258 direct-initialization. */
7261 if (MAYBE_CLASS_TYPE_P (type))
7262 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
7264 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum,
7268 /* If RETVAL is the address of, or a reference to, a local variable or
7269 temporary give an appropriate warning. */
7272 maybe_warn_about_returning_address_of_local (tree retval)
7274 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
7275 tree whats_returned = retval;
7279 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
7280 whats_returned = TREE_OPERAND (whats_returned, 1);
7281 else if (CONVERT_EXPR_P (whats_returned)
7282 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR)
7283 whats_returned = TREE_OPERAND (whats_returned, 0);
7288 if (TREE_CODE (whats_returned) != ADDR_EXPR)
7290 whats_returned = TREE_OPERAND (whats_returned, 0);
7292 if (TREE_CODE (valtype) == REFERENCE_TYPE)
7294 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
7295 || TREE_CODE (whats_returned) == TARGET_EXPR)
7297 warning (0, "returning reference to temporary");
7300 if (TREE_CODE (whats_returned) == VAR_DECL
7301 && DECL_NAME (whats_returned)
7302 && TEMP_NAME_P (DECL_NAME (whats_returned)))
7304 warning (0, "reference to non-lvalue returned");
7309 while (TREE_CODE (whats_returned) == COMPONENT_REF
7310 || TREE_CODE (whats_returned) == ARRAY_REF)
7311 whats_returned = TREE_OPERAND (whats_returned, 0);
7313 if (DECL_P (whats_returned)
7314 && DECL_NAME (whats_returned)
7315 && DECL_FUNCTION_SCOPE_P (whats_returned)
7316 && !(TREE_STATIC (whats_returned)
7317 || TREE_PUBLIC (whats_returned)))
7319 if (TREE_CODE (valtype) == REFERENCE_TYPE)
7320 warning (0, "reference to local variable %q+D returned",
7323 warning (0, "address of local variable %q+D returned",
7329 /* Check that returning RETVAL from the current function is valid.
7330 Return an expression explicitly showing all conversions required to
7331 change RETVAL into the function return type, and to assign it to
7332 the DECL_RESULT for the function. Set *NO_WARNING to true if
7333 code reaches end of non-void function warning shouldn't be issued
7334 on this RETURN_EXPR. */
7337 check_return_expr (tree retval, bool *no_warning)
7340 /* The type actually returned by the function, after any
7343 int fn_returns_value_p;
7344 bool named_return_value_okay_p;
7346 *no_warning = false;
7348 /* A `volatile' function is one that isn't supposed to return, ever.
7349 (This is a G++ extension, used to get better code for functions
7350 that call the `volatile' function.) */
7351 if (TREE_THIS_VOLATILE (current_function_decl))
7352 warning (0, "function declared %<noreturn%> has a %<return%> statement");
7354 /* Check for various simple errors. */
7355 if (DECL_DESTRUCTOR_P (current_function_decl))
7358 error ("returning a value from a destructor");
7361 else if (DECL_CONSTRUCTOR_P (current_function_decl))
7363 if (in_function_try_handler)
7364 /* If a return statement appears in a handler of the
7365 function-try-block of a constructor, the program is ill-formed. */
7366 error ("cannot return from a handler of a function-try-block of a constructor");
7368 /* You can't return a value from a constructor. */
7369 error ("returning a value from a constructor");
7373 /* As an extension, deduce lambda return type from a return statement
7374 anywhere in the body. */
7375 if (retval && LAMBDA_FUNCTION_P (current_function_decl))
7377 tree lambda = CLASSTYPE_LAMBDA_EXPR (current_class_type);
7378 if (LAMBDA_EXPR_DEDUCE_RETURN_TYPE_P (lambda))
7380 tree type = lambda_return_type (retval);
7381 tree oldtype = LAMBDA_EXPR_RETURN_TYPE (lambda);
7383 if (VOID_TYPE_P (type))
7385 else if (oldtype == NULL_TREE)
7387 pedwarn (input_location, OPT_pedantic, "lambda return type "
7388 "can only be deduced when the return statement is "
7389 "the only statement in the function body");
7390 apply_lambda_return_type (lambda, type);
7392 else if (!same_type_p (type, oldtype))
7393 error ("inconsistent types %qT and %qT deduced for "
7394 "lambda return type", type, oldtype);
7398 if (processing_template_decl)
7400 current_function_returns_value = 1;
7401 if (check_for_bare_parameter_packs (retval))
7402 retval = error_mark_node;
7406 /* When no explicit return-value is given in a function with a named
7407 return value, the named return value is used. */
7408 result = DECL_RESULT (current_function_decl);
7409 valtype = TREE_TYPE (result);
7410 gcc_assert (valtype != NULL_TREE);
7411 fn_returns_value_p = !VOID_TYPE_P (valtype);
7412 if (!retval && DECL_NAME (result) && fn_returns_value_p)
7415 /* Check for a return statement with no return value in a function
7416 that's supposed to return a value. */
7417 if (!retval && fn_returns_value_p)
7419 permerror (input_location, "return-statement with no value, in function returning %qT",
7421 /* Clear this, so finish_function won't say that we reach the
7422 end of a non-void function (which we don't, we gave a
7424 current_function_returns_null = 0;
7425 /* And signal caller that TREE_NO_WARNING should be set on the
7426 RETURN_EXPR to avoid control reaches end of non-void function
7427 warnings in tree-cfg.c. */
7430 /* Check for a return statement with a value in a function that
7431 isn't supposed to return a value. */
7432 else if (retval && !fn_returns_value_p)
7434 if (VOID_TYPE_P (TREE_TYPE (retval)))
7435 /* You can return a `void' value from a function of `void'
7436 type. In that case, we have to evaluate the expression for
7437 its side-effects. */
7438 finish_expr_stmt (retval);
7440 permerror (input_location, "return-statement with a value, in function "
7441 "returning 'void'");
7442 current_function_returns_null = 1;
7444 /* There's really no value to return, after all. */
7448 /* Remember that this function can sometimes return without a
7450 current_function_returns_null = 1;
7452 /* Remember that this function did return a value. */
7453 current_function_returns_value = 1;
7455 /* Check for erroneous operands -- but after giving ourselves a
7456 chance to provide an error about returning a value from a void
7458 if (error_operand_p (retval))
7460 current_function_return_value = error_mark_node;
7461 return error_mark_node;
7464 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
7465 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
7466 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
7467 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
7469 && retval && null_ptr_cst_p (retval))
7470 warning (0, "%<operator new%> must not return NULL unless it is "
7471 "declared %<throw()%> (or -fcheck-new is in effect)");
7473 /* Effective C++ rule 15. See also start_function. */
7475 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
7479 /* The function return type must be a reference to the current
7481 if (TREE_CODE (valtype) == REFERENCE_TYPE
7482 && same_type_ignoring_top_level_qualifiers_p
7483 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
7485 /* Returning '*this' is obviously OK. */
7486 if (retval == current_class_ref)
7488 /* If we are calling a function whose return type is the same of
7489 the current class reference, it is ok. */
7490 else if (TREE_CODE (retval) == INDIRECT_REF
7491 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
7496 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
7499 /* The fabled Named Return Value optimization, as per [class.copy]/15:
7501 [...] For a function with a class return type, if the expression
7502 in the return statement is the name of a local object, and the cv-
7503 unqualified type of the local object is the same as the function
7504 return type, an implementation is permitted to omit creating the tem-
7505 porary object to hold the function return value [...]
7507 So, if this is a value-returning function that always returns the same
7508 local variable, remember it.
7510 It might be nice to be more flexible, and choose the first suitable
7511 variable even if the function sometimes returns something else, but
7512 then we run the risk of clobbering the variable we chose if the other
7513 returned expression uses the chosen variable somehow. And people expect
7514 this restriction, anyway. (jason 2000-11-19)
7516 See finish_function and finalize_nrv for the rest of this optimization. */
7518 named_return_value_okay_p =
7519 (retval != NULL_TREE
7520 /* Must be a local, automatic variable. */
7521 && TREE_CODE (retval) == VAR_DECL
7522 && DECL_CONTEXT (retval) == current_function_decl
7523 && ! TREE_STATIC (retval)
7524 && ! DECL_ANON_UNION_VAR_P (retval)
7525 && (DECL_ALIGN (retval)
7526 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
7527 /* The cv-unqualified type of the returned value must be the
7528 same as the cv-unqualified return type of the
7530 && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))),
7532 (TREE_TYPE (TREE_TYPE (current_function_decl)))))
7533 /* And the returned value must be non-volatile. */
7534 && ! TYPE_VOLATILE (TREE_TYPE (retval)));
7536 if (fn_returns_value_p && flag_elide_constructors)
7538 if (named_return_value_okay_p
7539 && (current_function_return_value == NULL_TREE
7540 || current_function_return_value == retval))
7541 current_function_return_value = retval;
7543 current_function_return_value = error_mark_node;
7546 /* We don't need to do any conversions when there's nothing being
7551 /* Do any required conversions. */
7552 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
7553 /* No conversions are required. */
7557 /* The type the function is declared to return. */
7558 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
7559 int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
7561 /* The functype's return type will have been set to void, if it
7562 was an incomplete type. Just treat this as 'return;' */
7563 if (VOID_TYPE_P (functype))
7564 return error_mark_node;
7566 /* Under C++0x [12.8/16 class.copy], a returned lvalue is sometimes
7567 treated as an rvalue for the purposes of overload resolution to
7568 favor move constructors over copy constructors. */
7569 if ((cxx_dialect != cxx98)
7570 && named_return_value_okay_p
7571 /* The variable must not have the `volatile' qualifier. */
7572 && !(cp_type_quals (TREE_TYPE (retval)) & TYPE_QUAL_VOLATILE)
7573 /* The return type must be a class type. */
7574 && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
7575 flags = flags | LOOKUP_PREFER_RVALUE;
7577 /* First convert the value to the function's return type, then
7578 to the type of return value's location to handle the
7579 case that functype is smaller than the valtype. */
7580 retval = convert_for_initialization
7581 (NULL_TREE, functype, retval, flags, "return", NULL_TREE, 0,
7582 tf_warning_or_error);
7583 retval = convert (valtype, retval);
7585 /* If the conversion failed, treat this just like `return;'. */
7586 if (retval == error_mark_node)
7588 /* We can't initialize a register from a AGGR_INIT_EXPR. */
7589 else if (! cfun->returns_struct
7590 && TREE_CODE (retval) == TARGET_EXPR
7591 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
7592 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
7593 TREE_OPERAND (retval, 0));
7595 maybe_warn_about_returning_address_of_local (retval);
7598 /* Actually copy the value returned into the appropriate location. */
7599 if (retval && retval != result)
7600 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
7606 /* Returns nonzero if the pointer-type FROM can be converted to the
7607 pointer-type TO via a qualification conversion. If CONSTP is -1,
7608 then we return nonzero if the pointers are similar, and the
7609 cv-qualification signature of FROM is a proper subset of that of TO.
7611 If CONSTP is positive, then all outer pointers have been
7615 comp_ptr_ttypes_real (tree to, tree from, int constp)
7617 bool to_more_cv_qualified = false;
7618 bool is_opaque_pointer = false;
7620 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7622 if (TREE_CODE (to) != TREE_CODE (from))
7625 if (TREE_CODE (from) == OFFSET_TYPE
7626 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
7627 TYPE_OFFSET_BASETYPE (to)))
7630 /* Const and volatile mean something different for function types,
7631 so the usual checks are not appropriate. */
7632 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
7634 /* In Objective-C++, some types may have been 'volatilized' by
7635 the compiler for EH; when comparing them here, the volatile
7636 qualification must be ignored. */
7637 bool objc_quals_match = objc_type_quals_match (to, from);
7639 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
7642 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
7646 to_more_cv_qualified = true;
7650 constp &= TYPE_READONLY (to);
7653 if (TREE_CODE (to) == VECTOR_TYPE)
7654 is_opaque_pointer = vector_targets_convertible_p (to, from);
7656 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
7657 return ((constp >= 0 || to_more_cv_qualified)
7658 && (is_opaque_pointer
7659 || same_type_ignoring_top_level_qualifiers_p (to, from)));
7663 /* When comparing, say, char ** to char const **, this function takes
7664 the 'char *' and 'char const *'. Do not pass non-pointer/reference
7665 types to this function. */
7668 comp_ptr_ttypes (tree to, tree from)
7670 return comp_ptr_ttypes_real (to, from, 1);
7673 /* Returns true iff FNTYPE is a non-class type that involves
7674 error_mark_node. We can get FUNCTION_TYPE with buried error_mark_node
7675 if a parameter type is ill-formed. */
7678 error_type_p (const_tree type)
7682 switch (TREE_CODE (type))
7688 case REFERENCE_TYPE:
7690 return error_type_p (TREE_TYPE (type));
7694 if (error_type_p (TREE_TYPE (type)))
7696 for (t = TYPE_ARG_TYPES (type); t; t = TREE_CHAIN (t))
7697 if (error_type_p (TREE_VALUE (t)))
7702 if (TYPE_PTRMEMFUNC_P (type))
7703 return error_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type));
7711 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
7712 type or inheritance-related types, regardless of cv-quals. */
7715 ptr_reasonably_similar (const_tree to, const_tree from)
7717 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7719 /* Any target type is similar enough to void. */
7720 if (TREE_CODE (to) == VOID_TYPE)
7721 return !error_type_p (from);
7722 if (TREE_CODE (from) == VOID_TYPE)
7723 return !error_type_p (to);
7725 if (TREE_CODE (to) != TREE_CODE (from))
7728 if (TREE_CODE (from) == OFFSET_TYPE
7729 && comptypes (TYPE_OFFSET_BASETYPE (to),
7730 TYPE_OFFSET_BASETYPE (from),
7731 COMPARE_BASE | COMPARE_DERIVED))
7734 if (TREE_CODE (to) == VECTOR_TYPE
7735 && vector_types_convertible_p (to, from, false))
7738 if (TREE_CODE (to) == INTEGER_TYPE
7739 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
7742 if (TREE_CODE (to) == FUNCTION_TYPE)
7743 return !error_type_p (to) && !error_type_p (from);
7745 if (TREE_CODE (to) != POINTER_TYPE)
7747 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
7748 COMPARE_BASE | COMPARE_DERIVED);
7752 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
7753 pointer-to-member types) are the same, ignoring cv-qualification at
7757 comp_ptr_ttypes_const (tree to, tree from)
7759 bool is_opaque_pointer = false;
7761 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7763 if (TREE_CODE (to) != TREE_CODE (from))
7766 if (TREE_CODE (from) == OFFSET_TYPE
7767 && same_type_p (TYPE_OFFSET_BASETYPE (from),
7768 TYPE_OFFSET_BASETYPE (to)))
7771 if (TREE_CODE (to) == VECTOR_TYPE)
7772 is_opaque_pointer = vector_targets_convertible_p (to, from);
7774 if (TREE_CODE (to) != POINTER_TYPE)
7775 return (is_opaque_pointer
7776 || same_type_ignoring_top_level_qualifiers_p (to, from));
7780 /* Returns the type qualifiers for this type, including the qualifiers on the
7781 elements for an array type. */
7784 cp_type_quals (const_tree type)
7786 /* This CONST_CAST is okay because strip_array_types returns its
7787 argument unmodified and we assign it to a const_tree. */
7788 type = strip_array_types (CONST_CAST_TREE(type));
7789 if (type == error_mark_node)
7790 return TYPE_UNQUALIFIED;
7791 return TYPE_QUALS (type);
7794 /* Returns nonzero if the TYPE is const from a C++ perspective: look inside
7798 cp_type_readonly (const_tree type)
7800 /* This CONST_CAST is okay because strip_array_types returns its
7801 argument unmodified and we assign it to a const_tree. */
7802 type = strip_array_types (CONST_CAST_TREE(type));
7803 return TYPE_READONLY (type);
7806 /* Returns nonzero if TYPE is const or volatile. */
7809 cv_qualified_p (const_tree type)
7811 int quals = cp_type_quals (type);
7812 return (quals & (TYPE_QUAL_CONST|TYPE_QUAL_VOLATILE)) != 0;
7815 /* Returns nonzero if the TYPE contains a mutable member. */
7818 cp_has_mutable_p (const_tree type)
7820 /* This CONST_CAST is okay because strip_array_types returns its
7821 argument unmodified and we assign it to a const_tree. */
7822 type = strip_array_types (CONST_CAST_TREE(type));
7824 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
7827 /* Set TREE_READONLY and TREE_VOLATILE on DECL as indicated by the
7828 TYPE_QUALS. For a VAR_DECL, this may be an optimistic
7829 approximation. In particular, consider:
7832 struct S { int i; };
7833 const S s = { f(); }
7835 Here, we will make "s" as TREE_READONLY (because it is declared
7836 "const") -- only to reverse ourselves upon seeing that the
7837 initializer is non-constant. */
7840 cp_apply_type_quals_to_decl (int type_quals, tree decl)
7842 tree type = TREE_TYPE (decl);
7844 if (type == error_mark_node)
7847 if (TREE_CODE (decl) == TYPE_DECL)
7850 if (TREE_CODE (type) == FUNCTION_TYPE
7851 && type_quals != TYPE_UNQUALIFIED)
7853 /* This was an error in C++98 (cv-qualifiers cannot be added to
7854 a function type), but DR 295 makes the code well-formed by
7855 dropping the extra qualifiers. */
7858 tree bad_type = build_qualified_type (type, type_quals);
7859 pedwarn (input_location, OPT_pedantic,
7860 "ignoring %qV qualifiers added to function type %qT",
7864 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
7868 /* Avoid setting TREE_READONLY incorrectly. */
7869 if (/* If the object has a constructor, the constructor may modify
7871 TYPE_NEEDS_CONSTRUCTING (type)
7872 /* If the type isn't complete, we don't know yet if it will need
7874 || !COMPLETE_TYPE_P (type)
7875 /* If the type has a mutable component, that component might be
7877 || TYPE_HAS_MUTABLE_P (type))
7878 type_quals &= ~TYPE_QUAL_CONST;
7880 c_apply_type_quals_to_decl (type_quals, decl);
7883 /* Subroutine of casts_away_constness. Make T1 and T2 point at
7884 exemplar types such that casting T1 to T2 is casting away constness
7885 if and only if there is no implicit conversion from T1 to T2. */
7888 casts_away_constness_r (tree *t1, tree *t2)
7893 /* [expr.const.cast]
7895 For multi-level pointer to members and multi-level mixed pointers
7896 and pointers to members (conv.qual), the "member" aspect of a
7897 pointer to member level is ignored when determining if a const
7898 cv-qualifier has been cast away. */
7899 /* [expr.const.cast]
7901 For two pointer types:
7903 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
7904 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
7907 casting from X1 to X2 casts away constness if, for a non-pointer
7908 type T there does not exist an implicit conversion (clause
7911 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
7915 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
7916 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
7917 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
7919 *t1 = cp_build_qualified_type (void_type_node,
7920 cp_type_quals (*t1));
7921 *t2 = cp_build_qualified_type (void_type_node,
7922 cp_type_quals (*t2));
7926 quals1 = cp_type_quals (*t1);
7927 quals2 = cp_type_quals (*t2);
7929 if (TYPE_PTRMEM_P (*t1))
7930 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
7932 *t1 = TREE_TYPE (*t1);
7933 if (TYPE_PTRMEM_P (*t2))
7934 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
7936 *t2 = TREE_TYPE (*t2);
7938 casts_away_constness_r (t1, t2);
7939 *t1 = build_pointer_type (*t1);
7940 *t2 = build_pointer_type (*t2);
7941 *t1 = cp_build_qualified_type (*t1, quals1);
7942 *t2 = cp_build_qualified_type (*t2, quals2);
7945 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
7948 ??? This function returns non-zero if casting away qualifiers not
7949 just const. We would like to return to the caller exactly which
7950 qualifiers are casted away to give more accurate diagnostics.
7954 casts_away_constness (tree t1, tree t2)
7956 if (TREE_CODE (t2) == REFERENCE_TYPE)
7958 /* [expr.const.cast]
7960 Casting from an lvalue of type T1 to an lvalue of type T2
7961 using a reference cast casts away constness if a cast from an
7962 rvalue of type "pointer to T1" to the type "pointer to T2"
7963 casts away constness. */
7964 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
7965 return casts_away_constness (build_pointer_type (t1),
7966 build_pointer_type (TREE_TYPE (t2)));
7969 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
7970 /* [expr.const.cast]
7972 Casting from an rvalue of type "pointer to data member of X
7973 of type T1" to the type "pointer to data member of Y of type
7974 T2" casts away constness if a cast from an rvalue of type
7975 "pointer to T1" to the type "pointer to T2" casts away
7977 return casts_away_constness
7978 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
7979 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
7981 /* Casting away constness is only something that makes sense for
7982 pointer or reference types. */
7983 if (TREE_CODE (t1) != POINTER_TYPE
7984 || TREE_CODE (t2) != POINTER_TYPE)
7987 /* Top-level qualifiers don't matter. */
7988 t1 = TYPE_MAIN_VARIANT (t1);
7989 t2 = TYPE_MAIN_VARIANT (t2);
7990 casts_away_constness_r (&t1, &t2);
7991 if (!can_convert (t2, t1))
7997 /* If T is a REFERENCE_TYPE return the type to which T refers.
7998 Otherwise, return T itself. */
8001 non_reference (tree t)
8003 if (TREE_CODE (t) == REFERENCE_TYPE)
8009 /* Return nonzero if REF is an lvalue valid for this language;
8010 otherwise, print an error message and return zero. USE says
8011 how the lvalue is being used and so selects the error message. */
8014 lvalue_or_else (tree ref, enum lvalue_use use, tsubst_flags_t complain)
8016 int win = lvalue_p (ref);
8018 if (!win && (complain & tf_error))