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
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 (int, tree *, tree, tree, 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 /* FIXME: Attributes. */
264 gcc_assert (ARITHMETIC_TYPE_P (t1)
265 || TREE_CODE (t1) == VECTOR_TYPE
266 || UNSCOPED_ENUM_P (t1));
267 gcc_assert (ARITHMETIC_TYPE_P (t2)
268 || TREE_CODE (t2) == VECTOR_TYPE
269 || UNSCOPED_ENUM_P (t2));
271 /* In what follows, we slightly generalize the rules given in [expr] so
272 as to deal with `long long' and `complex'. First, merge the
274 attributes = (*targetm.merge_type_attributes) (t1, t2);
276 /* If one type is complex, form the common type of the non-complex
277 components, then make that complex. Use T1 or T2 if it is the
279 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
281 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
282 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
284 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
286 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
287 return build_type_attribute_variant (t1, attributes);
288 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
289 return build_type_attribute_variant (t2, attributes);
291 return build_type_attribute_variant (build_complex_type (subtype),
295 if (code1 == VECTOR_TYPE)
297 /* When we get here we should have two vectors of the same size.
298 Just prefer the unsigned one if present. */
299 if (TYPE_UNSIGNED (t1))
300 return build_type_attribute_variant (t1, attributes);
302 return build_type_attribute_variant (t2, attributes);
305 /* If only one is real, use it as the result. */
306 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
307 return build_type_attribute_variant (t1, attributes);
308 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
309 return build_type_attribute_variant (t2, attributes);
311 /* Both real or both integers; use the one with greater precision. */
312 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
313 return build_type_attribute_variant (t1, attributes);
314 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
315 return build_type_attribute_variant (t2, attributes);
317 /* The types are the same; no need to do anything fancy. */
318 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
319 return build_type_attribute_variant (t1, attributes);
321 if (code1 != REAL_TYPE)
323 /* If one is unsigned long long, then convert the other to unsigned
325 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
326 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
327 return build_type_attribute_variant (long_long_unsigned_type_node,
329 /* If one is a long long, and the other is an unsigned long, and
330 long long can represent all the values of an unsigned long, then
331 convert to a long long. Otherwise, convert to an unsigned long
332 long. Otherwise, if either operand is long long, convert the
335 Since we're here, we know the TYPE_PRECISION is the same;
336 therefore converting to long long cannot represent all the values
337 of an unsigned long, so we choose unsigned long long in that
339 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
340 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
342 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
343 ? long_long_unsigned_type_node
344 : long_long_integer_type_node);
345 return build_type_attribute_variant (t, attributes);
348 /* Go through the same procedure, but for longs. */
349 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
350 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
351 return build_type_attribute_variant (long_unsigned_type_node,
353 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
354 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
356 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
357 ? long_unsigned_type_node : long_integer_type_node);
358 return build_type_attribute_variant (t, attributes);
360 /* Otherwise prefer the unsigned one. */
361 if (TYPE_UNSIGNED (t1))
362 return build_type_attribute_variant (t1, attributes);
364 return build_type_attribute_variant (t2, attributes);
368 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
369 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
370 return build_type_attribute_variant (long_double_type_node,
372 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
373 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
374 return build_type_attribute_variant (double_type_node,
376 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
377 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
378 return build_type_attribute_variant (float_type_node,
381 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
382 the standard C++ floating-point types. Logic earlier in this
383 function has already eliminated the possibility that
384 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
385 compelling reason to choose one or the other. */
386 return build_type_attribute_variant (t1, attributes);
390 /* T1 and T2 are arithmetic or enumeration types. Return the type
391 that will result from the "usual arithmetic conversions" on T1 and
392 T2 as described in [expr]. */
395 type_after_usual_arithmetic_conversions (tree t1, tree t2)
397 gcc_assert (ARITHMETIC_TYPE_P (t1)
398 || TREE_CODE (t1) == VECTOR_TYPE
399 || UNSCOPED_ENUM_P (t1));
400 gcc_assert (ARITHMETIC_TYPE_P (t2)
401 || TREE_CODE (t2) == VECTOR_TYPE
402 || UNSCOPED_ENUM_P (t2));
404 /* Perform the integral promotions. We do not promote real types here. */
405 if (INTEGRAL_OR_ENUMERATION_TYPE_P (t1)
406 && INTEGRAL_OR_ENUMERATION_TYPE_P (t1))
408 t1 = type_promotes_to (t1);
409 t2 = type_promotes_to (t2);
412 return cp_common_type (t1, t2);
415 /* Subroutine of composite_pointer_type to implement the recursive
416 case. See that function for documentation fo the parameters. */
419 composite_pointer_type_r (tree t1, tree t2, const char* location,
420 tsubst_flags_t complain)
427 /* Determine the types pointed to by T1 and T2. */
428 if (TREE_CODE (t1) == POINTER_TYPE)
430 pointee1 = TREE_TYPE (t1);
431 pointee2 = TREE_TYPE (t2);
435 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
436 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
441 Otherwise, the composite pointer type is a pointer type
442 similar (_conv.qual_) to the type of one of the operands,
443 with a cv-qualification signature (_conv.qual_) that is the
444 union of the cv-qualification signatures of the operand
446 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
447 result_type = pointee1;
448 else if ((TREE_CODE (pointee1) == POINTER_TYPE
449 && TREE_CODE (pointee2) == POINTER_TYPE)
450 || (TYPE_PTR_TO_MEMBER_P (pointee1)
451 && TYPE_PTR_TO_MEMBER_P (pointee2)))
452 result_type = composite_pointer_type_r (pointee1, pointee2, location,
456 if (complain & tf_error)
457 permerror (input_location, "%s between distinct pointer types %qT and %qT "
460 result_type = void_type_node;
462 result_type = cp_build_qualified_type (result_type,
463 (cp_type_quals (pointee1)
464 | cp_type_quals (pointee2)));
465 /* If the original types were pointers to members, so is the
467 if (TYPE_PTR_TO_MEMBER_P (t1))
469 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
470 TYPE_PTRMEM_CLASS_TYPE (t2))
471 && (complain & tf_error))
472 permerror (input_location, "%s between distinct pointer types %qT and %qT "
475 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
479 result_type = build_pointer_type (result_type);
481 /* Merge the attributes. */
482 attributes = (*targetm.merge_type_attributes) (t1, t2);
483 return build_type_attribute_variant (result_type, attributes);
486 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
487 ARG1 and ARG2 are the values with those types. The LOCATION is a
488 string describing the current location, in case an error occurs.
490 This routine also implements the computation of a common type for
491 pointers-to-members as per [expr.eq]. */
494 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
495 const char* location, tsubst_flags_t complain)
502 If one operand is a null pointer constant, the composite pointer
503 type is the type of the other operand. */
504 if (null_ptr_cst_p (arg1))
506 if (null_ptr_cst_p (arg2))
513 If one of the operands has type "pointer to cv1 void*", then
514 the other has type "pointer to cv2T", and the composite pointer
515 type is "pointer to cv12 void", where cv12 is the union of cv1
518 If either type is a pointer to void, make sure it is T1. */
519 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
527 /* Now, if T1 is a pointer to void, merge the qualifiers. */
528 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
533 if (TYPE_PTRFN_P (t2) && (complain & tf_error))
534 pedwarn (input_location, OPT_pedantic, "ISO C++ forbids %s "
535 "between pointer of type %<void *%> and pointer-to-function",
538 = cp_build_qualified_type (void_type_node,
539 (cp_type_quals (TREE_TYPE (t1))
540 | cp_type_quals (TREE_TYPE (t2))));
541 result_type = build_pointer_type (result_type);
542 /* Merge the attributes. */
543 attributes = (*targetm.merge_type_attributes) (t1, t2);
544 return build_type_attribute_variant (result_type, attributes);
547 if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE
548 && TREE_CODE (t2) == POINTER_TYPE)
550 if (objc_compare_types (t1, t2, -3, NULL_TREE))
554 /* [expr.eq] permits the application of a pointer conversion to
555 bring the pointers to a common type. */
556 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
557 && CLASS_TYPE_P (TREE_TYPE (t1))
558 && CLASS_TYPE_P (TREE_TYPE (t2))
559 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
562 class1 = TREE_TYPE (t1);
563 class2 = TREE_TYPE (t2);
565 if (DERIVED_FROM_P (class1, class2))
566 t2 = (build_pointer_type
567 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
568 else if (DERIVED_FROM_P (class2, class1))
569 t1 = (build_pointer_type
570 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
573 if (complain & tf_error)
574 error ("%s between distinct pointer types %qT and %qT "
575 "lacks a cast", location, t1, t2);
576 return error_mark_node;
579 /* [expr.eq] permits the application of a pointer-to-member
580 conversion to change the class type of one of the types. */
581 else if (TYPE_PTR_TO_MEMBER_P (t1)
582 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
583 TYPE_PTRMEM_CLASS_TYPE (t2)))
585 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
586 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
588 if (DERIVED_FROM_P (class1, class2))
589 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
590 else if (DERIVED_FROM_P (class2, class1))
591 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
594 if (complain & tf_error)
595 error ("%s between distinct pointer-to-member types %qT and %qT "
596 "lacks a cast", location, t1, t2);
597 return error_mark_node;
601 return composite_pointer_type_r (t1, t2, location, complain);
604 /* Return the merged type of two types.
605 We assume that comptypes has already been done and returned 1;
606 if that isn't so, this may crash.
608 This just combines attributes and default arguments; any other
609 differences would cause the two types to compare unalike. */
612 merge_types (tree t1, tree t2)
614 enum tree_code code1;
615 enum tree_code code2;
618 /* Save time if the two types are the same. */
621 if (original_type (t1) == original_type (t2))
624 /* If one type is nonsense, use the other. */
625 if (t1 == error_mark_node)
627 if (t2 == error_mark_node)
630 /* Merge the attributes. */
631 attributes = (*targetm.merge_type_attributes) (t1, t2);
633 if (TYPE_PTRMEMFUNC_P (t1))
634 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
635 if (TYPE_PTRMEMFUNC_P (t2))
636 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
638 code1 = TREE_CODE (t1);
639 code2 = TREE_CODE (t2);
645 /* For two pointers, do this recursively on the target type. */
647 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
648 int quals = cp_type_quals (t1);
650 if (code1 == POINTER_TYPE)
651 t1 = build_pointer_type (target);
653 t1 = cp_build_reference_type (target, TYPE_REF_IS_RVALUE (t1));
654 t1 = build_type_attribute_variant (t1, attributes);
655 t1 = cp_build_qualified_type (t1, quals);
657 if (TREE_CODE (target) == METHOD_TYPE)
658 t1 = build_ptrmemfunc_type (t1);
667 quals = cp_type_quals (t1);
668 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
669 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
670 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
672 t1 = cp_build_qualified_type (t1, quals);
678 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
679 /* Save space: see if the result is identical to one of the args. */
680 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
681 return build_type_attribute_variant (t1, attributes);
682 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
683 return build_type_attribute_variant (t2, attributes);
684 /* Merge the element types, and have a size if either arg has one. */
685 t1 = build_cplus_array_type
686 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
691 /* Function types: prefer the one that specified arg types.
692 If both do, merge the arg types. Also merge the return types. */
694 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
695 tree p1 = TYPE_ARG_TYPES (t1);
696 tree p2 = TYPE_ARG_TYPES (t2);
699 /* Save space: see if the result is identical to one of the args. */
700 if (valtype == TREE_TYPE (t1) && ! p2)
701 return cp_build_type_attribute_variant (t1, attributes);
702 if (valtype == TREE_TYPE (t2) && ! p1)
703 return cp_build_type_attribute_variant (t2, attributes);
705 /* Simple way if one arg fails to specify argument types. */
706 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
708 rval = build_function_type (valtype, p2);
709 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
710 rval = build_exception_variant (rval, raises);
711 return cp_build_type_attribute_variant (rval, attributes);
713 raises = TYPE_RAISES_EXCEPTIONS (t1);
714 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
716 rval = build_function_type (valtype, p1);
718 rval = build_exception_variant (rval, raises);
719 return cp_build_type_attribute_variant (rval, attributes);
722 rval = build_function_type (valtype, commonparms (p1, p2));
723 t1 = build_exception_variant (rval, raises);
729 /* Get this value the long way, since TYPE_METHOD_BASETYPE
730 is just the main variant of this. */
731 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
732 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
735 /* If this was a member function type, get back to the
736 original type of type member function (i.e., without
737 the class instance variable up front. */
738 t1 = build_function_type (TREE_TYPE (t1),
739 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
740 t2 = build_function_type (TREE_TYPE (t2),
741 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
742 t3 = merge_types (t1, t2);
743 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
744 TYPE_ARG_TYPES (t3));
745 t1 = build_exception_variant (t3, raises);
750 /* There is no need to merge attributes into a TYPENAME_TYPE.
751 When the type is instantiated it will have whatever
752 attributes result from the instantiation. */
758 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
760 else if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
763 return cp_build_type_attribute_variant (t1, attributes);
766 /* Wrapper around cp_common_type that is used by c-common.c and other
767 front end optimizations that remove promotions.
769 Return the common type for two arithmetic types T1 and T2 under the
770 usual arithmetic conversions. The default conversions have already
771 been applied, and enumerated types converted to their compatible
775 common_type (tree t1, tree t2)
777 /* If one type is nonsense, use the other */
778 if (t1 == error_mark_node)
780 if (t2 == error_mark_node)
783 return cp_common_type (t1, t2);
786 /* Return the common type of two pointer types T1 and T2. This is the
787 type for the result of most arithmetic operations if the operands
788 have the given two types.
790 We assume that comp_target_types has already been done and returned
791 nonzero; if that isn't so, this may crash. */
794 common_pointer_type (tree t1, tree t2)
796 gcc_assert ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
797 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
798 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)));
800 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
801 "conversion", tf_warning_or_error);
804 /* Compare two exception specifier types for exactness or subsetness, if
805 allowed. Returns false for mismatch, true for match (same, or
808 [except.spec] "If a class X ... objects of class X or any class publicly
809 and unambiguously derived from X. Similarly, if a pointer type Y * ...
810 exceptions of type Y * or that are pointers to any type publicly and
811 unambiguously derived from Y. Otherwise a function only allows exceptions
812 that have the same type ..."
813 This does not mention cv qualifiers and is different to what throw
814 [except.throw] and catch [except.catch] will do. They will ignore the
815 top level cv qualifiers, and allow qualifiers in the pointer to class
818 We implement the letter of the standard. */
821 comp_except_types (tree a, tree b, bool exact)
823 if (same_type_p (a, b))
827 if (cp_type_quals (a) || cp_type_quals (b))
830 if (TREE_CODE (a) == POINTER_TYPE
831 && TREE_CODE (b) == POINTER_TYPE)
835 if (cp_type_quals (a) || cp_type_quals (b))
839 if (TREE_CODE (a) != RECORD_TYPE
840 || TREE_CODE (b) != RECORD_TYPE)
843 if (PUBLICLY_UNIQUELY_DERIVED_P (a, b))
849 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
850 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
851 otherwise it must be exact. Exception lists are unordered, but
852 we've already filtered out duplicates. Most lists will be in order,
853 we should try to make use of that. */
856 comp_except_specs (const_tree t1, const_tree t2, bool exact)
865 if (t1 == NULL_TREE) /* T1 is ... */
866 return t2 == NULL_TREE || !exact;
867 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
868 return t2 != NULL_TREE && !TREE_VALUE (t2);
869 if (t2 == NULL_TREE) /* T2 is ... */
871 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
874 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
875 Count how many we find, to determine exactness. For exact matching and
876 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
878 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
880 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
882 tree a = TREE_VALUE (probe);
883 tree b = TREE_VALUE (t2);
885 if (comp_except_types (a, b, exact))
887 if (probe == base && exact)
888 base = TREE_CHAIN (probe);
893 if (probe == NULL_TREE)
896 return !exact || base == NULL_TREE || length == list_length (t1);
899 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
900 [] can match [size]. */
903 comp_array_types (const_tree t1, const_tree t2, bool allow_redeclaration)
912 /* The type of the array elements must be the same. */
913 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
916 d1 = TYPE_DOMAIN (t1);
917 d2 = TYPE_DOMAIN (t2);
922 /* If one of the arrays is dimensionless, and the other has a
923 dimension, they are of different types. However, it is valid to
931 declarations for an array object can specify
932 array types that differ by the presence or absence of a major
933 array bound (_dcl.array_). */
935 return allow_redeclaration;
937 /* Check that the dimensions are the same. */
939 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
941 max1 = TYPE_MAX_VALUE (d1);
942 max2 = TYPE_MAX_VALUE (d2);
943 if (processing_template_decl && !abi_version_at_least (2)
944 && !value_dependent_expression_p (max1)
945 && !value_dependent_expression_p (max2))
947 /* With abi-1 we do not fold non-dependent array bounds, (and
948 consequently mangle them incorrectly). We must therefore
949 fold them here, to verify the domains have the same
955 if (!cp_tree_equal (max1, max2))
961 /* Subroutine in comptypes. */
964 structural_comptypes (tree t1, tree t2, int strict)
969 /* Suppress errors caused by previously reported errors. */
970 if (t1 == error_mark_node || t2 == error_mark_node)
973 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
975 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
976 current instantiation. */
977 if (TREE_CODE (t1) == TYPENAME_TYPE)
978 t1 = resolve_typename_type (t1, /*only_current_p=*/true);
980 if (TREE_CODE (t2) == TYPENAME_TYPE)
981 t2 = resolve_typename_type (t2, /*only_current_p=*/true);
983 if (TYPE_PTRMEMFUNC_P (t1))
984 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
985 if (TYPE_PTRMEMFUNC_P (t2))
986 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
988 /* Different classes of types can't be compatible. */
989 if (TREE_CODE (t1) != TREE_CODE (t2))
992 /* Qualifiers must match. For array types, we will check when we
993 recur on the array element types. */
994 if (TREE_CODE (t1) != ARRAY_TYPE
995 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
997 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
1000 /* Allow for two different type nodes which have essentially the same
1001 definition. Note that we already checked for equality of the type
1002 qualifiers (just above). */
1004 if (TREE_CODE (t1) != ARRAY_TYPE
1005 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
1008 /* Compare the types. Break out if they could be the same. */
1009 switch (TREE_CODE (t1))
1013 /* All void and bool types are the same. */
1017 case FIXED_POINT_TYPE:
1019 /* With these nodes, we can't determine type equivalence by
1020 looking at what is stored in the nodes themselves, because
1021 two nodes might have different TYPE_MAIN_VARIANTs but still
1022 represent the same type. For example, wchar_t and int could
1023 have the same properties (TYPE_PRECISION, TYPE_MIN_VALUE,
1024 TYPE_MAX_VALUE, etc.), but have different TYPE_MAIN_VARIANTs
1025 and are distinct types. On the other hand, int and the
1028 typedef int INT __attribute((may_alias));
1030 have identical properties, different TYPE_MAIN_VARIANTs, but
1031 represent the same type. The canonical type system keeps
1032 track of equivalence in this case, so we fall back on it. */
1033 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1035 case TEMPLATE_TEMPLATE_PARM:
1036 case BOUND_TEMPLATE_TEMPLATE_PARM:
1037 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1038 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2)
1039 || (TEMPLATE_TYPE_PARAMETER_PACK (t1)
1040 != TEMPLATE_TYPE_PARAMETER_PACK (t2)))
1042 if (!comp_template_parms
1043 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1044 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1046 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1048 /* Don't check inheritance. */
1049 strict = COMPARE_STRICT;
1054 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1055 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1056 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1057 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1060 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1062 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1068 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1069 strict & ~COMPARE_REDECLARATION))
1071 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1075 case REFERENCE_TYPE:
1076 if (TYPE_REF_IS_RVALUE (t1) != TYPE_REF_IS_RVALUE (t2))
1078 /* fall through to checks for pointer types */
1081 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1082 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)
1083 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1089 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1091 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1096 /* Target types must match incl. qualifiers. */
1097 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1101 case TEMPLATE_TYPE_PARM:
1102 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1103 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2)
1104 || (TEMPLATE_TYPE_PARAMETER_PACK (t1)
1105 != TEMPLATE_TYPE_PARAMETER_PACK (t2)))
1110 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1111 TYPENAME_TYPE_FULLNAME (t2)))
1113 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1117 case UNBOUND_CLASS_TEMPLATE:
1118 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1120 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1125 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1130 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1131 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1135 case TYPE_PACK_EXPANSION:
1136 return same_type_p (PACK_EXPANSION_PATTERN (t1),
1137 PACK_EXPANSION_PATTERN (t2));
1140 if (DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t1)
1141 != DECLTYPE_TYPE_ID_EXPR_OR_MEMBER_ACCESS_P (t2)
1142 || !cp_tree_equal (DECLTYPE_TYPE_EXPR (t1),
1143 DECLTYPE_TYPE_EXPR (t2)))
1151 /* If we get here, we know that from a target independent POV the
1152 types are the same. Make sure the target attributes are also
1154 return targetm.comp_type_attributes (t1, t2);
1157 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
1158 is a bitwise-or of the COMPARE_* flags. */
1161 comptypes (tree t1, tree t2, int strict)
1163 if (strict == COMPARE_STRICT)
1168 if (t1 == error_mark_node || t2 == error_mark_node)
1171 if (TYPE_STRUCTURAL_EQUALITY_P (t1) || TYPE_STRUCTURAL_EQUALITY_P (t2))
1172 /* At least one of the types requires structural equality, so
1173 perform a deep check. */
1174 return structural_comptypes (t1, t2, strict);
1176 #ifdef ENABLE_CHECKING
1177 if (USE_CANONICAL_TYPES)
1179 bool result = structural_comptypes (t1, t2, strict);
1181 if (result && TYPE_CANONICAL (t1) != TYPE_CANONICAL (t2))
1182 /* The two types are structurally equivalent, but their
1183 canonical types were different. This is a failure of the
1184 canonical type propagation code.*/
1186 ("canonical types differ for identical types %T and %T",
1188 else if (!result && TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2))
1189 /* Two types are structurally different, but the canonical
1190 types are the same. This means we were over-eager in
1191 assigning canonical types. */
1193 ("same canonical type node for different types %T and %T",
1199 if (USE_CANONICAL_TYPES)
1200 return TYPE_CANONICAL (t1) == TYPE_CANONICAL (t2);
1203 return structural_comptypes (t1, t2, strict);
1205 else if (strict == COMPARE_STRUCTURAL)
1206 return structural_comptypes (t1, t2, COMPARE_STRICT);
1208 return structural_comptypes (t1, t2, strict);
1211 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1214 at_least_as_qualified_p (const_tree type1, const_tree type2)
1216 int q1 = cp_type_quals (type1);
1217 int q2 = cp_type_quals (type2);
1219 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1220 return (q1 & q2) == q2;
1223 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1224 more cv-qualified that TYPE1, and 0 otherwise. */
1227 comp_cv_qualification (const_tree type1, const_tree type2)
1229 int q1 = cp_type_quals (type1);
1230 int q2 = cp_type_quals (type2);
1235 if ((q1 & q2) == q2)
1237 else if ((q1 & q2) == q1)
1243 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1244 subset of the cv-qualification signature of TYPE2, and the types
1245 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1248 comp_cv_qual_signature (tree type1, tree type2)
1250 if (comp_ptr_ttypes_real (type2, type1, -1))
1252 else if (comp_ptr_ttypes_real (type1, type2, -1))
1258 /* Subroutines of `comptypes'. */
1260 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1261 equivalent in the sense that functions with those parameter types
1262 can have equivalent types. The two lists must be equivalent,
1263 element by element. */
1266 compparms (const_tree parms1, const_tree parms2)
1270 /* An unspecified parmlist matches any specified parmlist
1271 whose argument types don't need default promotions. */
1273 for (t1 = parms1, t2 = parms2;
1275 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1277 /* If one parmlist is shorter than the other,
1278 they fail to match. */
1281 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1288 /* Process a sizeof or alignof expression where the operand is a
1292 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1297 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1298 if (type == error_mark_node)
1299 return error_mark_node;
1301 type = non_reference (type);
1302 if (TREE_CODE (type) == METHOD_TYPE)
1305 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpointer_arith,
1306 "invalid application of %qs to a member function",
1307 operator_name_info[(int) op].name);
1308 value = size_one_node;
1311 dependent_p = dependent_type_p (type);
1313 complete_type (type);
1315 /* VLA types will have a non-constant size. In the body of an
1316 uninstantiated template, we don't need to try to compute the
1317 value, because the sizeof expression is not an integral
1318 constant expression in that case. And, if we do try to
1319 compute the value, we'll likely end up with SAVE_EXPRs, which
1320 the template substitution machinery does not expect to see. */
1321 || (processing_template_decl
1322 && COMPLETE_TYPE_P (type)
1323 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST))
1325 value = build_min (op, size_type_node, type);
1326 TREE_READONLY (value) = 1;
1330 return c_sizeof_or_alignof_type (complete_type (type),
1335 /* Return the size of the type, without producing any warnings for
1336 types whose size cannot be taken. This routine should be used only
1337 in some other routine that has already produced a diagnostic about
1338 using the size of such a type. */
1340 cxx_sizeof_nowarn (tree type)
1342 if (TREE_CODE (type) == FUNCTION_TYPE
1343 || TREE_CODE (type) == VOID_TYPE
1344 || TREE_CODE (type) == ERROR_MARK)
1345 return size_one_node;
1346 else if (!COMPLETE_TYPE_P (type))
1347 return size_zero_node;
1349 return cxx_sizeof_or_alignof_type (type, SIZEOF_EXPR, false);
1352 /* Process a sizeof expression where the operand is an expression. */
1355 cxx_sizeof_expr (tree e, tsubst_flags_t complain)
1357 if (e == error_mark_node)
1358 return error_mark_node;
1360 if (processing_template_decl)
1362 e = build_min (SIZEOF_EXPR, size_type_node, e);
1363 TREE_SIDE_EFFECTS (e) = 0;
1364 TREE_READONLY (e) = 1;
1369 if (TREE_CODE (e) == COMPONENT_REF
1370 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1371 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1373 if (complain & tf_error)
1374 error ("invalid application of %<sizeof%> to a bit-field");
1376 return error_mark_node;
1379 else if (is_overloaded_fn (e))
1381 if (complain & tf_error)
1382 permerror (input_location, "ISO C++ forbids applying %<sizeof%> to an expression of "
1385 return error_mark_node;
1388 else if (type_unknown_p (e))
1390 if (complain & tf_error)
1391 cxx_incomplete_type_error (e, TREE_TYPE (e));
1393 return error_mark_node;
1399 return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, complain & tf_error);
1402 /* Implement the __alignof keyword: Return the minimum required
1403 alignment of E, measured in bytes. For VAR_DECL's and
1404 FIELD_DECL's return DECL_ALIGN (which can be set from an
1405 "aligned" __attribute__ specification). */
1408 cxx_alignof_expr (tree e, tsubst_flags_t complain)
1412 if (e == error_mark_node)
1413 return error_mark_node;
1415 if (processing_template_decl)
1417 e = build_min (ALIGNOF_EXPR, size_type_node, e);
1418 TREE_SIDE_EFFECTS (e) = 0;
1419 TREE_READONLY (e) = 1;
1424 if (TREE_CODE (e) == VAR_DECL)
1425 t = size_int (DECL_ALIGN_UNIT (e));
1426 else if (TREE_CODE (e) == COMPONENT_REF
1427 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1428 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1430 if (complain & tf_error)
1431 error ("invalid application of %<__alignof%> to a bit-field");
1433 return error_mark_node;
1436 else if (TREE_CODE (e) == COMPONENT_REF
1437 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL)
1438 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1)));
1439 else if (is_overloaded_fn (e))
1441 if (complain & tf_error)
1442 permerror (input_location, "ISO C++ forbids applying %<__alignof%> to an expression of "
1445 return error_mark_node;
1446 if (TREE_CODE (e) == FUNCTION_DECL)
1447 t = size_int (DECL_ALIGN_UNIT (e));
1451 else if (type_unknown_p (e))
1453 if (complain & tf_error)
1454 cxx_incomplete_type_error (e, TREE_TYPE (e));
1456 return error_mark_node;
1460 return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR,
1461 complain & tf_error);
1463 return fold_convert (size_type_node, t);
1466 /* Process a sizeof or alignof expression E with code OP where the operand
1467 is an expression. */
1470 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op, bool complain)
1472 if (op == SIZEOF_EXPR)
1473 return cxx_sizeof_expr (e, complain? tf_warning_or_error : tf_none);
1475 return cxx_alignof_expr (e, complain? tf_warning_or_error : tf_none);
1478 /* EXPR is being used in a context that is not a function call.
1483 The expression can be used only as the left-hand operand of a
1484 member function call.
1486 [expr.mptr.operator]
1488 If the result of .* or ->* is a function, then that result can be
1489 used only as the operand for the function call operator ().
1491 by issuing an error message if appropriate. Returns true iff EXPR
1492 violates these rules. */
1495 invalid_nonstatic_memfn_p (const_tree expr, tsubst_flags_t complain)
1497 if (TREE_CODE (TREE_TYPE (expr)) == METHOD_TYPE)
1499 if (complain & tf_error)
1500 error ("invalid use of non-static member function");
1506 /* If EXP is a reference to a bitfield, and the type of EXP does not
1507 match the declared type of the bitfield, return the declared type
1508 of the bitfield. Otherwise, return NULL_TREE. */
1511 is_bitfield_expr_with_lowered_type (const_tree exp)
1513 switch (TREE_CODE (exp))
1516 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)
1517 ? TREE_OPERAND (exp, 1)
1518 : TREE_OPERAND (exp, 0)))
1520 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2));
1523 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1));
1527 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1533 field = TREE_OPERAND (exp, 1);
1534 if (TREE_CODE (field) != FIELD_DECL || !DECL_BIT_FIELD_TYPE (field))
1536 if (same_type_ignoring_top_level_qualifiers_p
1537 (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field)))
1539 return DECL_BIT_FIELD_TYPE (field);
1543 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (exp, 0)))
1544 == TYPE_MAIN_VARIANT (TREE_TYPE (exp)))
1545 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 0));
1553 /* Like is_bitfield_with_lowered_type, except that if EXP is not a
1554 bitfield with a lowered type, the type of EXP is returned, rather
1558 unlowered_expr_type (const_tree exp)
1562 type = is_bitfield_expr_with_lowered_type (exp);
1564 type = TREE_TYPE (exp);
1569 /* Perform the conversions in [expr] that apply when an lvalue appears
1570 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1571 function-to-pointer conversions. In addition, manifest constants
1572 are replaced by their values, and bitfield references are converted
1573 to their declared types.
1575 Although the returned value is being used as an rvalue, this
1576 function does not wrap the returned expression in a
1577 NON_LVALUE_EXPR; the caller is expected to be mindful of the fact
1578 that the return value is no longer an lvalue. */
1581 decay_conversion (tree exp)
1584 enum tree_code code;
1586 type = TREE_TYPE (exp);
1587 if (type == error_mark_node)
1588 return error_mark_node;
1590 if (type_unknown_p (exp))
1592 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1593 return error_mark_node;
1596 exp = decl_constant_value (exp);
1597 if (error_operand_p (exp))
1598 return error_mark_node;
1600 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1601 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1602 code = TREE_CODE (type);
1603 if (code == VOID_TYPE)
1605 error ("void value not ignored as it ought to be");
1606 return error_mark_node;
1608 if (invalid_nonstatic_memfn_p (exp, tf_warning_or_error))
1609 return error_mark_node;
1610 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1611 return cp_build_unary_op (ADDR_EXPR, exp, 0, tf_warning_or_error);
1612 if (code == ARRAY_TYPE)
1617 if (TREE_CODE (exp) == INDIRECT_REF)
1618 return build_nop (build_pointer_type (TREE_TYPE (type)),
1619 TREE_OPERAND (exp, 0));
1621 if (TREE_CODE (exp) == COMPOUND_EXPR)
1623 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1624 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1625 TREE_OPERAND (exp, 0), op1);
1629 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1631 error ("invalid use of non-lvalue array");
1632 return error_mark_node;
1635 ptrtype = build_pointer_type (TREE_TYPE (type));
1637 if (TREE_CODE (exp) == VAR_DECL)
1639 if (!cxx_mark_addressable (exp))
1640 return error_mark_node;
1641 adr = build_nop (ptrtype, build_address (exp));
1644 /* This way is better for a COMPONENT_REF since it can
1645 simplify the offset for a component. */
1646 adr = cp_build_unary_op (ADDR_EXPR, exp, 1, tf_warning_or_error);
1647 return cp_convert (ptrtype, adr);
1650 /* If a bitfield is used in a context where integral promotion
1651 applies, then the caller is expected to have used
1652 default_conversion. That function promotes bitfields correctly
1653 before calling this function. At this point, if we have a
1654 bitfield referenced, we may assume that is not subject to
1655 promotion, and that, therefore, the type of the resulting rvalue
1656 is the declared type of the bitfield. */
1657 exp = convert_bitfield_to_declared_type (exp);
1659 /* We do not call rvalue() here because we do not want to wrap EXP
1660 in a NON_LVALUE_EXPR. */
1664 Non-class rvalues always have cv-unqualified types. */
1665 type = TREE_TYPE (exp);
1666 if (!CLASS_TYPE_P (type) && cp_type_quals (type))
1667 exp = build_nop (TYPE_MAIN_VARIANT (type), exp);
1672 /* Perform preparatory conversions, as part of the "usual arithmetic
1673 conversions". In particular, as per [expr]:
1675 Whenever an lvalue expression appears as an operand of an
1676 operator that expects the rvalue for that operand, the
1677 lvalue-to-rvalue, array-to-pointer, or function-to-pointer
1678 standard conversions are applied to convert the expression to an
1681 In addition, we perform integral promotions here, as those are
1682 applied to both operands to a binary operator before determining
1683 what additional conversions should apply. */
1686 default_conversion (tree exp)
1688 /* Perform the integral promotions first so that bitfield
1689 expressions (which may promote to "int", even if the bitfield is
1690 declared "unsigned") are promoted correctly. */
1691 if (INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1692 exp = perform_integral_promotions (exp);
1693 /* Perform the other conversions. */
1694 exp = decay_conversion (exp);
1699 /* EXPR is an expression with an integral or enumeration type.
1700 Perform the integral promotions in [conv.prom], and return the
1704 perform_integral_promotions (tree expr)
1711 If the bitfield has an enumerated type, it is treated as any
1712 other value of that type for promotion purposes. */
1713 type = is_bitfield_expr_with_lowered_type (expr);
1714 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
1715 type = TREE_TYPE (expr);
1716 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1717 promoted_type = type_promotes_to (type);
1718 if (type != promoted_type)
1719 expr = cp_convert (promoted_type, expr);
1723 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1724 decay_conversion to one. */
1727 string_conv_p (const_tree totype, const_tree exp, int warn)
1731 if (TREE_CODE (totype) != POINTER_TYPE)
1734 t = TREE_TYPE (totype);
1735 if (!same_type_p (t, char_type_node)
1736 && !same_type_p (t, char16_type_node)
1737 && !same_type_p (t, char32_type_node)
1738 && !same_type_p (t, wchar_type_node))
1741 if (TREE_CODE (exp) == STRING_CST)
1743 /* Make sure that we don't try to convert between char and wide chars. */
1744 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1749 /* Is this a string constant which has decayed to 'const char *'? */
1750 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1751 if (!same_type_p (TREE_TYPE (exp), t))
1754 if (TREE_CODE (exp) != ADDR_EXPR
1755 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1759 /* This warning is not very useful, as it complains about printf. */
1761 warning (OPT_Wwrite_strings,
1762 "deprecated conversion from string constant to %qT",
1768 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1769 can, for example, use as an lvalue. This code used to be in
1770 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1771 expressions, where we're dealing with aggregates. But now it's again only
1772 called from unary_complex_lvalue. The case (in particular) that led to
1773 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1777 rationalize_conditional_expr (enum tree_code code, tree t,
1778 tsubst_flags_t complain)
1780 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1781 the first operand is always the one to be used if both operands
1782 are equal, so we know what conditional expression this used to be. */
1783 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1785 tree op0 = TREE_OPERAND (t, 0);
1786 tree op1 = TREE_OPERAND (t, 1);
1788 /* The following code is incorrect if either operand side-effects. */
1789 gcc_assert (!TREE_SIDE_EFFECTS (op0)
1790 && !TREE_SIDE_EFFECTS (op1));
1792 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1793 ? LE_EXPR : GE_EXPR),
1794 op0, TREE_CODE (op0),
1795 op1, TREE_CODE (op1),
1796 /*overloaded_p=*/NULL,
1798 cp_build_unary_op (code, op0, 0, complain),
1799 cp_build_unary_op (code, op1, 0, complain),
1804 build_conditional_expr (TREE_OPERAND (t, 0),
1805 cp_build_unary_op (code, TREE_OPERAND (t, 1), 0,
1807 cp_build_unary_op (code, TREE_OPERAND (t, 2), 0,
1812 /* Given the TYPE of an anonymous union field inside T, return the
1813 FIELD_DECL for the field. If not found return NULL_TREE. Because
1814 anonymous unions can nest, we must also search all anonymous unions
1815 that are directly reachable. */
1818 lookup_anon_field (tree t, tree type)
1822 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1824 if (TREE_STATIC (field))
1826 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1829 /* If we find it directly, return the field. */
1830 if (DECL_NAME (field) == NULL_TREE
1831 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1836 /* Otherwise, it could be nested, search harder. */
1837 if (DECL_NAME (field) == NULL_TREE
1838 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1840 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1848 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1849 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1850 non-NULL, it indicates the path to the base used to name MEMBER.
1851 If PRESERVE_REFERENCE is true, the expression returned will have
1852 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1853 returned will have the type referred to by the reference.
1855 This function does not perform access control; that is either done
1856 earlier by the parser when the name of MEMBER is resolved to MEMBER
1857 itself, or later when overload resolution selects one of the
1858 functions indicated by MEMBER. */
1861 build_class_member_access_expr (tree object, tree member,
1862 tree access_path, bool preserve_reference,
1863 tsubst_flags_t complain)
1867 tree result = NULL_TREE;
1869 if (error_operand_p (object) || error_operand_p (member))
1870 return error_mark_node;
1872 gcc_assert (DECL_P (member) || BASELINK_P (member));
1876 The type of the first expression shall be "class object" (of a
1878 object_type = TREE_TYPE (object);
1879 if (!currently_open_class (object_type)
1880 && !complete_type_or_else (object_type, object))
1881 return error_mark_node;
1882 if (!CLASS_TYPE_P (object_type))
1884 if (complain & tf_error)
1885 error ("request for member %qD in %qE, which is of non-class type %qT",
1886 member, object, object_type);
1887 return error_mark_node;
1890 /* The standard does not seem to actually say that MEMBER must be a
1891 member of OBJECT_TYPE. However, that is clearly what is
1893 if (DECL_P (member))
1895 member_scope = DECL_CLASS_CONTEXT (member);
1897 if (TREE_DEPRECATED (member))
1898 warn_deprecated_use (member);
1901 member_scope = BINFO_TYPE (BASELINK_ACCESS_BINFO (member));
1902 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1903 presently be the anonymous union. Go outwards until we find a
1904 type related to OBJECT_TYPE. */
1905 while (ANON_AGGR_TYPE_P (member_scope)
1906 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1908 member_scope = TYPE_CONTEXT (member_scope);
1909 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1911 if (complain & tf_error)
1913 if (TREE_CODE (member) == FIELD_DECL)
1914 error ("invalid use of nonstatic data member %qE", member);
1916 error ("%qD is not a member of %qT", member, object_type);
1918 return error_mark_node;
1921 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1922 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1923 in the front end; only _DECLs and _REFs are lvalues in the back end. */
1925 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1927 object = cp_build_indirect_ref (temp, NULL, complain);
1930 /* In [expr.ref], there is an explicit list of the valid choices for
1931 MEMBER. We check for each of those cases here. */
1932 if (TREE_CODE (member) == VAR_DECL)
1934 /* A static data member. */
1936 /* If OBJECT has side-effects, they are supposed to occur. */
1937 if (TREE_SIDE_EFFECTS (object))
1938 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1940 else if (TREE_CODE (member) == FIELD_DECL)
1942 /* A non-static data member. */
1947 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1948 && integer_zerop (TREE_OPERAND (object, 0)));
1950 /* Convert OBJECT to the type of MEMBER. */
1951 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1952 TYPE_MAIN_VARIANT (member_scope)))
1957 binfo = lookup_base (access_path ? access_path : object_type,
1958 member_scope, ba_unique, &kind);
1959 if (binfo == error_mark_node)
1960 return error_mark_node;
1962 /* It is invalid to try to get to a virtual base of a
1963 NULL object. The most common cause is invalid use of
1965 if (null_object_p && kind == bk_via_virtual)
1967 if (complain & tf_error)
1969 error ("invalid access to non-static data member %qD of "
1972 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
1974 return error_mark_node;
1977 /* Convert to the base. */
1978 object = build_base_path (PLUS_EXPR, object, binfo,
1980 /* If we found the base successfully then we should be able
1981 to convert to it successfully. */
1982 gcc_assert (object != error_mark_node);
1985 /* Complain about other invalid uses of offsetof, even though they will
1986 give the right answer. Note that we complain whether or not they
1987 actually used the offsetof macro, since there's no way to know at this
1988 point. So we just give a warning, instead of a pedwarn. */
1989 /* Do not produce this warning for base class field references, because
1990 we know for a fact that didn't come from offsetof. This does occur
1991 in various testsuite cases where a null object is passed where a
1992 vtable access is required. */
1993 if (null_object_p && warn_invalid_offsetof
1994 && CLASSTYPE_NON_POD_P (object_type)
1995 && !DECL_FIELD_IS_BASE (member)
1997 && (complain & tf_warning))
1999 warning (OPT_Winvalid_offsetof,
2000 "invalid access to non-static data member %qD "
2001 " of NULL object", member);
2002 warning (OPT_Winvalid_offsetof,
2003 "(perhaps the %<offsetof%> macro was used incorrectly)");
2006 /* If MEMBER is from an anonymous aggregate, we have converted
2007 OBJECT so that it refers to the class containing the
2008 anonymous union. Generate a reference to the anonymous union
2009 itself, and recur to find MEMBER. */
2010 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
2011 /* When this code is called from build_field_call, the
2012 object already has the type of the anonymous union.
2013 That is because the COMPONENT_REF was already
2014 constructed, and was then disassembled before calling
2015 build_field_call. After the function-call code is
2016 cleaned up, this waste can be eliminated. */
2017 && (!same_type_ignoring_top_level_qualifiers_p
2018 (TREE_TYPE (object), DECL_CONTEXT (member))))
2020 tree anonymous_union;
2022 anonymous_union = lookup_anon_field (TREE_TYPE (object),
2023 DECL_CONTEXT (member));
2024 object = build_class_member_access_expr (object,
2026 /*access_path=*/NULL_TREE,
2031 /* Compute the type of the field, as described in [expr.ref]. */
2032 type_quals = TYPE_UNQUALIFIED;
2033 member_type = TREE_TYPE (member);
2034 if (TREE_CODE (member_type) != REFERENCE_TYPE)
2036 type_quals = (cp_type_quals (member_type)
2037 | cp_type_quals (object_type));
2039 /* A field is const (volatile) if the enclosing object, or the
2040 field itself, is const (volatile). But, a mutable field is
2041 not const, even within a const object. */
2042 if (DECL_MUTABLE_P (member))
2043 type_quals &= ~TYPE_QUAL_CONST;
2044 member_type = cp_build_qualified_type (member_type, type_quals);
2047 result = build3 (COMPONENT_REF, member_type, object, member,
2049 result = fold_if_not_in_template (result);
2051 /* Mark the expression const or volatile, as appropriate. Even
2052 though we've dealt with the type above, we still have to mark the
2053 expression itself. */
2054 if (type_quals & TYPE_QUAL_CONST)
2055 TREE_READONLY (result) = 1;
2056 if (type_quals & TYPE_QUAL_VOLATILE)
2057 TREE_THIS_VOLATILE (result) = 1;
2059 else if (BASELINK_P (member))
2061 /* The member is a (possibly overloaded) member function. */
2065 /* If the MEMBER is exactly one static member function, then we
2066 know the type of the expression. Otherwise, we must wait
2067 until overload resolution has been performed. */
2068 functions = BASELINK_FUNCTIONS (member);
2069 if (TREE_CODE (functions) == FUNCTION_DECL
2070 && DECL_STATIC_FUNCTION_P (functions))
2071 type = TREE_TYPE (functions);
2073 type = unknown_type_node;
2074 /* Note that we do not convert OBJECT to the BASELINK_BINFO
2075 base. That will happen when the function is called. */
2076 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
2078 else if (TREE_CODE (member) == CONST_DECL)
2080 /* The member is an enumerator. */
2082 /* If OBJECT has side-effects, they are supposed to occur. */
2083 if (TREE_SIDE_EFFECTS (object))
2084 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
2089 if (complain & tf_error)
2090 error ("invalid use of %qD", member);
2091 return error_mark_node;
2094 if (!preserve_reference)
2097 If E2 is declared to have type "reference to T", then ... the
2098 type of E1.E2 is T. */
2099 result = convert_from_reference (result);
2104 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
2105 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
2108 lookup_destructor (tree object, tree scope, tree dtor_name)
2110 tree object_type = TREE_TYPE (object);
2111 tree dtor_type = TREE_OPERAND (dtor_name, 0);
2114 if (scope && !check_dtor_name (scope, dtor_type))
2116 error ("qualified type %qT does not match destructor name ~%qT",
2118 return error_mark_node;
2120 if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
2122 error ("the type being destroyed is %qT, but the destructor refers to %qT",
2123 TYPE_MAIN_VARIANT (object_type), dtor_type);
2124 return error_mark_node;
2126 expr = lookup_member (dtor_type, complete_dtor_identifier,
2127 /*protect=*/1, /*want_type=*/false);
2128 expr = (adjust_result_of_qualified_name_lookup
2129 (expr, dtor_type, object_type));
2133 /* An expression of the form "A::template B" has been resolved to
2134 DECL. Issue a diagnostic if B is not a template or template
2138 check_template_keyword (tree decl)
2140 /* The standard says:
2144 If a name prefixed by the keyword template is not a member
2145 template, the program is ill-formed.
2147 DR 228 removed the restriction that the template be a member
2150 DR 96, if accepted would add the further restriction that explicit
2151 template arguments must be provided if the template keyword is
2152 used, but, as of 2005-10-16, that DR is still in "drafting". If
2153 this DR is accepted, then the semantic checks here can be
2154 simplified, as the entity named must in fact be a template
2155 specialization, rather than, as at present, a set of overloaded
2156 functions containing at least one template function. */
2157 if (TREE_CODE (decl) != TEMPLATE_DECL
2158 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
2160 if (!is_overloaded_fn (decl))
2161 permerror (input_location, "%qD is not a template", decl);
2166 if (BASELINK_P (fns))
2167 fns = BASELINK_FUNCTIONS (fns);
2170 tree fn = OVL_CURRENT (fns);
2171 if (TREE_CODE (fn) == TEMPLATE_DECL
2172 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2174 if (TREE_CODE (fn) == FUNCTION_DECL
2175 && DECL_USE_TEMPLATE (fn)
2176 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
2178 fns = OVL_NEXT (fns);
2181 permerror (input_location, "%qD is not a template", decl);
2186 /* This function is called by the parser to process a class member
2187 access expression of the form OBJECT.NAME. NAME is a node used by
2188 the parser to represent a name; it is not yet a DECL. It may,
2189 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2190 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2191 there is no reason to do the lookup twice, so the parser keeps the
2192 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2193 be a template via the use of the "A::template B" syntax. */
2196 finish_class_member_access_expr (tree object, tree name, bool template_p,
2197 tsubst_flags_t complain)
2202 tree access_path = NULL_TREE;
2203 tree orig_object = object;
2204 tree orig_name = name;
2206 if (object == error_mark_node || name == error_mark_node)
2207 return error_mark_node;
2209 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2210 if (!objc_is_public (object, name))
2211 return error_mark_node;
2213 object_type = TREE_TYPE (object);
2215 if (processing_template_decl)
2217 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2218 dependent_type_p (object_type)
2219 /* If NAME is just an IDENTIFIER_NODE, then the expression
2221 || TREE_CODE (object) == IDENTIFIER_NODE
2222 /* If NAME is "f<args>", where either 'f' or 'args' is
2223 dependent, then the expression is dependent. */
2224 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2225 && dependent_template_id_p (TREE_OPERAND (name, 0),
2226 TREE_OPERAND (name, 1)))
2227 /* If NAME is "T::X" where "T" is dependent, then the
2228 expression is dependent. */
2229 || (TREE_CODE (name) == SCOPE_REF
2230 && TYPE_P (TREE_OPERAND (name, 0))
2231 && dependent_type_p (TREE_OPERAND (name, 0))))
2232 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2233 object = build_non_dependent_expr (object);
2238 The type of the first expression shall be "class object" (of a
2240 if (!currently_open_class (object_type)
2241 && !complete_type_or_else (object_type, object))
2242 return error_mark_node;
2243 if (!CLASS_TYPE_P (object_type))
2245 if (complain & tf_error)
2246 error ("request for member %qD in %qE, which is of non-class type %qT",
2247 name, object, object_type);
2248 return error_mark_node;
2251 if (BASELINK_P (name))
2252 /* A member function that has already been looked up. */
2256 bool is_template_id = false;
2257 tree template_args = NULL_TREE;
2260 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2262 is_template_id = true;
2263 template_args = TREE_OPERAND (name, 1);
2264 name = TREE_OPERAND (name, 0);
2266 if (TREE_CODE (name) == OVERLOAD)
2267 name = DECL_NAME (get_first_fn (name));
2268 else if (DECL_P (name))
2269 name = DECL_NAME (name);
2272 if (TREE_CODE (name) == SCOPE_REF)
2274 /* A qualified name. The qualifying class or namespace `S'
2275 has already been looked up; it is either a TYPE or a
2277 scope = TREE_OPERAND (name, 0);
2278 name = TREE_OPERAND (name, 1);
2280 /* If SCOPE is a namespace, then the qualified name does not
2281 name a member of OBJECT_TYPE. */
2282 if (TREE_CODE (scope) == NAMESPACE_DECL)
2284 if (complain & tf_error)
2285 error ("%<%D::%D%> is not a member of %qT",
2286 scope, name, object_type);
2287 return error_mark_node;
2290 gcc_assert (CLASS_TYPE_P (scope));
2291 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2292 || TREE_CODE (name) == BIT_NOT_EXPR);
2294 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2295 access_path = lookup_base (object_type, scope, ba_check, NULL);
2296 if (access_path == error_mark_node)
2297 return error_mark_node;
2300 if (complain & tf_error)
2301 error ("%qT is not a base of %qT", scope, object_type);
2302 return error_mark_node;
2308 access_path = object_type;
2311 if (TREE_CODE (name) == BIT_NOT_EXPR)
2312 member = lookup_destructor (object, scope, name);
2315 /* Look up the member. */
2316 member = lookup_member (access_path, name, /*protect=*/1,
2317 /*want_type=*/false);
2318 if (member == NULL_TREE)
2320 if (complain & tf_error)
2321 error ("%qD has no member named %qE", object_type, name);
2322 return error_mark_node;
2324 if (member == error_mark_node)
2325 return error_mark_node;
2330 tree templ = member;
2332 if (BASELINK_P (templ))
2333 templ = lookup_template_function (templ, template_args);
2336 if (complain & tf_error)
2337 error ("%qD is not a member template function", name);
2338 return error_mark_node;
2343 if (TREE_DEPRECATED (member))
2344 warn_deprecated_use (member);
2347 check_template_keyword (member);
2349 expr = build_class_member_access_expr (object, member, access_path,
2350 /*preserve_reference=*/false,
2352 if (processing_template_decl && expr != error_mark_node)
2354 if (BASELINK_P (member))
2356 if (TREE_CODE (orig_name) == SCOPE_REF)
2357 BASELINK_QUALIFIED_P (member) = 1;
2360 return build_min_non_dep (COMPONENT_REF, expr,
2361 orig_object, orig_name,
2368 /* Return an expression for the MEMBER_NAME field in the internal
2369 representation of PTRMEM, a pointer-to-member function. (Each
2370 pointer-to-member function type gets its own RECORD_TYPE so it is
2371 more convenient to access the fields by name than by FIELD_DECL.)
2372 This routine converts the NAME to a FIELD_DECL and then creates the
2373 node for the complete expression. */
2376 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2382 /* This code is a stripped down version of
2383 build_class_member_access_expr. It does not work to use that
2384 routine directly because it expects the object to be of class
2386 ptrmem_type = TREE_TYPE (ptrmem);
2387 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2388 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2389 /*want_type=*/false);
2390 member_type = cp_build_qualified_type (TREE_TYPE (member),
2391 cp_type_quals (ptrmem_type));
2392 return fold_build3 (COMPONENT_REF, member_type,
2393 ptrmem, member, NULL_TREE);
2396 /* Given an expression PTR for a pointer, return an expression
2397 for the value pointed to.
2398 ERRORSTRING is the name of the operator to appear in error messages.
2400 This function may need to overload OPERATOR_FNNAME.
2401 Must also handle REFERENCE_TYPEs for C++. */
2404 build_x_indirect_ref (tree expr, const char *errorstring,
2405 tsubst_flags_t complain)
2407 tree orig_expr = expr;
2410 if (processing_template_decl)
2412 if (type_dependent_expression_p (expr))
2413 return build_min_nt (INDIRECT_REF, expr);
2414 expr = build_non_dependent_expr (expr);
2417 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2418 NULL_TREE, /*overloaded_p=*/NULL, complain);
2420 rval = cp_build_indirect_ref (expr, errorstring, complain);
2422 if (processing_template_decl && rval != error_mark_node)
2423 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2428 /* Helper function called from c-common. */
2430 build_indirect_ref (location_t loc __attribute__ ((__unused__)),
2431 tree ptr, const char *errorstring)
2433 return cp_build_indirect_ref (ptr, errorstring, tf_warning_or_error);
2437 cp_build_indirect_ref (tree ptr, const char *errorstring,
2438 tsubst_flags_t complain)
2442 if (ptr == error_mark_node)
2443 return error_mark_node;
2445 if (ptr == current_class_ptr)
2446 return current_class_ref;
2448 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2449 ? ptr : decay_conversion (ptr));
2450 type = TREE_TYPE (pointer);
2452 if (POINTER_TYPE_P (type))
2456 If the type of the expression is "pointer to T," the type
2457 of the result is "T."
2459 We must use the canonical variant because certain parts of
2460 the back end, like fold, do pointer comparisons between
2462 tree t = canonical_type_variant (TREE_TYPE (type));
2464 if (CONVERT_EXPR_P (ptr)
2465 || TREE_CODE (ptr) == VIEW_CONVERT_EXPR)
2467 /* If a warning is issued, mark it to avoid duplicates from
2468 the backend. This only needs to be done at
2469 warn_strict_aliasing > 2. */
2470 if (warn_strict_aliasing > 2)
2471 if (strict_aliasing_warning (TREE_TYPE (TREE_OPERAND (ptr, 0)),
2472 type, TREE_OPERAND (ptr, 0)))
2473 TREE_NO_WARNING (ptr) = 1;
2476 if (VOID_TYPE_P (t))
2478 /* A pointer to incomplete type (other than cv void) can be
2479 dereferenced [expr.unary.op]/1 */
2480 if (complain & tf_error)
2481 error ("%qT is not a pointer-to-object type", type);
2482 return error_mark_node;
2484 else if (TREE_CODE (pointer) == ADDR_EXPR
2485 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2486 /* The POINTER was something like `&x'. We simplify `*&x' to
2488 return TREE_OPERAND (pointer, 0);
2491 tree ref = build1 (INDIRECT_REF, t, pointer);
2493 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2494 so that we get the proper error message if the result is used
2495 to assign to. Also, &* is supposed to be a no-op. */
2496 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2497 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2498 TREE_SIDE_EFFECTS (ref)
2499 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2503 else if (!(complain & tf_error))
2504 /* Don't emit any errors; we'll just return ERROR_MARK_NODE later. */
2506 /* `pointer' won't be an error_mark_node if we were given a
2507 pointer to member, so it's cool to check for this here. */
2508 else if (TYPE_PTR_TO_MEMBER_P (type))
2509 error ("invalid use of %qs on pointer to member", errorstring);
2510 else if (pointer != error_mark_node)
2513 error ("invalid type argument of %qs", errorstring);
2515 error ("invalid type argument");
2517 return error_mark_node;
2520 /* This handles expressions of the form "a[i]", which denotes
2523 This is logically equivalent in C to *(a+i), but we may do it differently.
2524 If A is a variable or a member, we generate a primitive ARRAY_REF.
2525 This avoids forcing the array out of registers, and can work on
2526 arrays that are not lvalues (for example, members of structures returned
2529 If INDEX is of some user-defined type, it must be converted to
2530 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2531 will inherit the type of the array, which will be some pointer type.
2533 LOC is the location to use in building the array reference. */
2536 build_array_ref (tree array, tree idx, location_t loc)
2542 error_at (loc, "subscript missing in array reference");
2543 return error_mark_node;
2546 if (TREE_TYPE (array) == error_mark_node
2547 || TREE_TYPE (idx) == error_mark_node)
2548 return error_mark_node;
2550 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2552 switch (TREE_CODE (array))
2556 tree value = build_array_ref (TREE_OPERAND (array, 1), idx, loc);
2557 ret = build2 (COMPOUND_EXPR, TREE_TYPE (value),
2558 TREE_OPERAND (array, 0), value);
2559 SET_EXPR_LOCATION (ret, loc);
2564 ret = build_conditional_expr
2565 (TREE_OPERAND (array, 0),
2566 build_array_ref (TREE_OPERAND (array, 1), idx, loc),
2567 build_array_ref (TREE_OPERAND (array, 2), idx, loc),
2568 tf_warning_or_error);
2569 protected_set_expr_location (ret, loc);
2576 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2580 warn_array_subscript_with_type_char (idx);
2582 if (!INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2584 error_at (loc, "array subscript is not an integer");
2585 return error_mark_node;
2588 /* Apply integral promotions *after* noticing character types.
2589 (It is unclear why we do these promotions -- the standard
2590 does not say that we should. In fact, the natural thing would
2591 seem to be to convert IDX to ptrdiff_t; we're performing
2592 pointer arithmetic.) */
2593 idx = perform_integral_promotions (idx);
2595 /* An array that is indexed by a non-constant
2596 cannot be stored in a register; we must be able to do
2597 address arithmetic on its address.
2598 Likewise an array of elements of variable size. */
2599 if (TREE_CODE (idx) != INTEGER_CST
2600 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2601 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2604 if (!cxx_mark_addressable (array))
2605 return error_mark_node;
2608 /* An array that is indexed by a constant value which is not within
2609 the array bounds cannot be stored in a register either; because we
2610 would get a crash in store_bit_field/extract_bit_field when trying
2611 to access a non-existent part of the register. */
2612 if (TREE_CODE (idx) == INTEGER_CST
2613 && TYPE_DOMAIN (TREE_TYPE (array))
2614 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2616 if (!cxx_mark_addressable (array))
2617 return error_mark_node;
2620 if (!lvalue_p (array))
2621 pedwarn (loc, OPT_pedantic,
2622 "ISO C++ forbids subscripting non-lvalue array");
2624 /* Note in C++ it is valid to subscript a `register' array, since
2625 it is valid to take the address of something with that
2626 storage specification. */
2630 while (TREE_CODE (foo) == COMPONENT_REF)
2631 foo = TREE_OPERAND (foo, 0);
2632 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2633 warning_at (loc, OPT_Wextra,
2634 "subscripting array declared %<register%>");
2637 type = TREE_TYPE (TREE_TYPE (array));
2638 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2639 /* Array ref is const/volatile if the array elements are
2640 or if the array is.. */
2641 TREE_READONLY (rval)
2642 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2643 TREE_SIDE_EFFECTS (rval)
2644 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2645 TREE_THIS_VOLATILE (rval)
2646 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2647 ret = require_complete_type (fold_if_not_in_template (rval));
2648 protected_set_expr_location (ret, loc);
2653 tree ar = default_conversion (array);
2654 tree ind = default_conversion (idx);
2656 /* Put the integer in IND to simplify error checking. */
2657 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2664 if (ar == error_mark_node)
2667 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2669 error_at (loc, "subscripted value is neither array nor pointer");
2670 return error_mark_node;
2672 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2674 error_at (loc, "array subscript is not an integer");
2675 return error_mark_node;
2678 warn_array_subscript_with_type_char (idx);
2680 ret = cp_build_indirect_ref (cp_build_binary_op (input_location,
2682 tf_warning_or_error),
2684 tf_warning_or_error);
2685 protected_set_expr_location (ret, loc);
2690 /* Resolve a pointer to member function. INSTANCE is the object
2691 instance to use, if the member points to a virtual member.
2693 This used to avoid checking for virtual functions if basetype
2694 has no virtual functions, according to an earlier ANSI draft.
2695 With the final ISO C++ rules, such an optimization is
2696 incorrect: A pointer to a derived member can be static_cast
2697 to pointer-to-base-member, as long as the dynamic object
2698 later has the right member. */
2701 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2703 if (TREE_CODE (function) == OFFSET_REF)
2704 function = TREE_OPERAND (function, 1);
2706 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2708 tree idx, delta, e1, e2, e3, vtbl, basetype;
2709 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2711 tree instance_ptr = *instance_ptrptr;
2712 tree instance_save_expr = 0;
2713 if (instance_ptr == error_mark_node)
2715 if (TREE_CODE (function) == PTRMEM_CST)
2717 /* Extracting the function address from a pmf is only
2718 allowed with -Wno-pmf-conversions. It only works for
2720 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2721 e1 = convert (fntype, e1);
2726 error ("object missing in use of %qE", function);
2727 return error_mark_node;
2731 if (TREE_SIDE_EFFECTS (instance_ptr))
2732 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2734 if (TREE_SIDE_EFFECTS (function))
2735 function = save_expr (function);
2737 /* Start by extracting all the information from the PMF itself. */
2738 e3 = pfn_from_ptrmemfunc (function);
2739 delta = delta_from_ptrmemfunc (function);
2740 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2741 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2743 case ptrmemfunc_vbit_in_pfn:
2744 e1 = cp_build_binary_op (input_location,
2745 BIT_AND_EXPR, idx, integer_one_node,
2746 tf_warning_or_error);
2747 idx = cp_build_binary_op (input_location,
2748 MINUS_EXPR, idx, integer_one_node,
2749 tf_warning_or_error);
2752 case ptrmemfunc_vbit_in_delta:
2753 e1 = cp_build_binary_op (input_location,
2754 BIT_AND_EXPR, delta, integer_one_node,
2755 tf_warning_or_error);
2756 delta = cp_build_binary_op (input_location,
2757 RSHIFT_EXPR, delta, integer_one_node,
2758 tf_warning_or_error);
2765 /* Convert down to the right base before using the instance. A
2766 special case is that in a pointer to member of class C, C may
2767 be incomplete. In that case, the function will of course be
2768 a member of C, and no conversion is required. In fact,
2769 lookup_base will fail in that case, because incomplete
2770 classes do not have BINFOs. */
2771 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2772 if (!same_type_ignoring_top_level_qualifiers_p
2773 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2775 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2776 basetype, ba_check, NULL);
2777 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2779 if (instance_ptr == error_mark_node)
2780 return error_mark_node;
2782 /* ...and then the delta in the PMF. */
2783 instance_ptr = build2 (POINTER_PLUS_EXPR, TREE_TYPE (instance_ptr),
2784 instance_ptr, fold_convert (sizetype, delta));
2786 /* Hand back the adjusted 'this' argument to our caller. */
2787 *instance_ptrptr = instance_ptr;
2789 /* Next extract the vtable pointer from the object. */
2790 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2792 vtbl = cp_build_indirect_ref (vtbl, NULL, tf_warning_or_error);
2794 /* Finally, extract the function pointer from the vtable. */
2795 e2 = fold_build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl,
2796 fold_convert (sizetype, idx));
2797 e2 = cp_build_indirect_ref (e2, NULL, tf_warning_or_error);
2798 TREE_CONSTANT (e2) = 1;
2800 /* When using function descriptors, the address of the
2801 vtable entry is treated as a function pointer. */
2802 if (TARGET_VTABLE_USES_DESCRIPTORS)
2803 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2804 cp_build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1,
2805 tf_warning_or_error));
2807 e2 = fold_convert (TREE_TYPE (e3), e2);
2808 e1 = build_conditional_expr (e1, e2, e3, tf_warning_or_error);
2810 /* Make sure this doesn't get evaluated first inside one of the
2811 branches of the COND_EXPR. */
2812 if (instance_save_expr)
2813 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2814 instance_save_expr, e1);
2821 /* Used by the C-common bits. */
2823 build_function_call (tree function, tree params)
2825 return cp_build_function_call (function, params, tf_warning_or_error);
2829 cp_build_function_call (tree function, tree params, tsubst_flags_t complain)
2831 tree fntype, fndecl;
2832 tree name = NULL_TREE;
2834 tree original = function;
2835 int nargs, parm_types_len;
2839 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2840 expressions, like those used for ObjC messenger dispatches. */
2841 function = objc_rewrite_function_call (function, params);
2843 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2844 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2845 if (TREE_CODE (function) == NOP_EXPR
2846 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2847 function = TREE_OPERAND (function, 0);
2849 if (TREE_CODE (function) == FUNCTION_DECL)
2851 name = DECL_NAME (function);
2853 mark_used (function);
2856 /* Convert anything with function type to a pointer-to-function. */
2857 if (DECL_MAIN_P (function) && (complain & tf_error))
2858 pedwarn (input_location, OPT_pedantic,
2859 "ISO C++ forbids calling %<::main%> from within program");
2861 function = build_addr_func (function);
2867 function = build_addr_func (function);
2870 if (function == error_mark_node)
2871 return error_mark_node;
2873 fntype = TREE_TYPE (function);
2875 if (TYPE_PTRMEMFUNC_P (fntype))
2877 if (complain & tf_error)
2878 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2879 "function in %<%E (...)%>, e.g. %<(... ->* %E) (...)%>",
2880 original, original);
2881 return error_mark_node;
2884 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2885 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2887 if (!((TREE_CODE (fntype) == POINTER_TYPE
2888 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2890 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2892 if (complain & tf_error)
2893 error ("%qE cannot be used as a function", original);
2894 return error_mark_node;
2897 /* fntype now gets the type of function pointed to. */
2898 fntype = TREE_TYPE (fntype);
2899 parm_types = TYPE_ARG_TYPES (fntype);
2901 /* Allocate storage for converted arguments. */
2902 parm_types_len = list_length (parm_types);
2903 nargs = list_length (params);
2904 if (parm_types_len > nargs)
2905 nargs = parm_types_len;
2906 argarray = (tree *) alloca (nargs * sizeof (tree));
2908 /* Convert the parameters to the types declared in the
2909 function prototype, or apply default promotions. */
2910 nargs = convert_arguments (nargs, argarray, parm_types,
2911 params, fndecl, LOOKUP_NORMAL,
2914 return error_mark_node;
2916 /* Check for errors in format strings and inappropriately
2918 check_function_arguments (TYPE_ATTRIBUTES (fntype), nargs, argarray,
2921 return build_cxx_call (function, nargs, argarray);
2924 /* Convert the actual parameter expressions in the list VALUES
2925 to the types in the list TYPELIST.
2926 If parmdecls is exhausted, or when an element has NULL as its type,
2927 perform the default conversions.
2929 Store the converted arguments in ARGARRAY. NARGS is the size of this array.
2931 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2933 This is also where warnings about wrong number of args are generated.
2935 Returns the actual number of arguments processed (which might be less
2936 than NARGS), or -1 on error.
2938 VALUES is a chain of TREE_LIST nodes with the elements of the list
2939 in the TREE_VALUE slots of those nodes.
2941 In C++, unspecified trailing parameters can be filled in with their
2942 default arguments, if such were specified. Do so here. */
2945 convert_arguments (int nargs, tree *argarray,
2946 tree typelist, tree values, tree fndecl, int flags,
2947 tsubst_flags_t complain)
2949 tree typetail, valtail;
2950 const char *called_thing = 0;
2953 /* Argument passing is always copy-initialization. */
2954 flags |= LOOKUP_ONLYCONVERTING;
2958 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2960 if (DECL_NAME (fndecl) == NULL_TREE
2961 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2962 called_thing = "constructor";
2964 called_thing = "member function";
2967 called_thing = "function";
2970 for (valtail = values, typetail = typelist;
2972 valtail = TREE_CHAIN (valtail), i++)
2974 tree type = typetail ? TREE_VALUE (typetail) : 0;
2975 tree val = TREE_VALUE (valtail);
2977 if (val == error_mark_node || type == error_mark_node)
2980 if (type == void_type_node)
2982 if (complain & tf_error)
2986 error ("too many arguments to %s %q+#D",
2987 called_thing, fndecl);
2988 error ("at this point in file");
2991 error ("too many arguments to function");
2998 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2999 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
3000 if (TREE_CODE (val) == NOP_EXPR
3001 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
3002 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
3003 val = TREE_OPERAND (val, 0);
3005 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
3007 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
3008 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
3009 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
3010 val = decay_conversion (val);
3013 if (val == error_mark_node)
3018 /* Formal parm type is specified by a function prototype. */
3021 if (!COMPLETE_TYPE_P (complete_type (type)))
3023 if (complain & tf_error)
3026 error ("parameter %P of %qD has incomplete type %qT",
3029 error ("parameter %P has incomplete type %qT", i, type);
3031 parmval = error_mark_node;
3035 parmval = convert_for_initialization
3036 (NULL_TREE, type, val, flags,
3037 "argument passing", fndecl, i, complain);
3038 parmval = convert_for_arg_passing (type, parmval);
3041 if (parmval == error_mark_node)
3044 argarray[i] = parmval;
3048 if (fndecl && DECL_BUILT_IN (fndecl)
3049 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
3050 /* Don't do ellipsis conversion for __built_in_constant_p
3051 as this will result in spurious warnings for non-POD
3053 val = require_complete_type (val);
3055 val = convert_arg_to_ellipsis (val);
3061 typetail = TREE_CHAIN (typetail);
3064 if (typetail != 0 && typetail != void_list_node)
3066 /* See if there are default arguments that can be used. Because
3067 we hold default arguments in the FUNCTION_TYPE (which is so
3068 wrong), we can see default parameters here from deduced
3069 contexts (and via typeof) for indirect function calls.
3070 Fortunately we know whether we have a function decl to
3071 provide default arguments in a language conformant
3073 if (fndecl && TREE_PURPOSE (typetail)
3074 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
3076 for (; typetail != void_list_node; ++i)
3079 = convert_default_arg (TREE_VALUE (typetail),
3080 TREE_PURPOSE (typetail),
3083 if (parmval == error_mark_node)
3086 argarray[i] = parmval;
3087 typetail = TREE_CHAIN (typetail);
3088 /* ends with `...'. */
3089 if (typetail == NULL_TREE)
3095 if (complain & tf_error)
3099 error ("too few arguments to %s %q+#D",
3100 called_thing, fndecl);
3101 error ("at this point in file");
3104 error ("too few arguments to function");
3110 gcc_assert (i <= nargs);
3114 /* Build a binary-operation expression, after performing default
3115 conversions on the operands. CODE is the kind of expression to
3116 build. ARG1 and ARG2 are the arguments. ARG1_CODE and ARG2_CODE
3117 are the tree codes which correspond to ARG1 and ARG2 when issuing
3118 warnings about possibly misplaced parentheses. They may differ
3119 from the TREE_CODE of ARG1 and ARG2 if the parser has done constant
3120 folding (e.g., if the parser sees "a | 1 + 1", it may call this
3121 routine with ARG2 being an INTEGER_CST and ARG2_CODE == PLUS_EXPR).
3122 To avoid issuing any parentheses warnings, pass ARG1_CODE and/or
3123 ARG2_CODE as ERROR_MARK. */
3126 build_x_binary_op (enum tree_code code, tree arg1, enum tree_code arg1_code,
3127 tree arg2, enum tree_code arg2_code, bool *overloaded_p,
3128 tsubst_flags_t complain)
3137 if (processing_template_decl)
3139 if (type_dependent_expression_p (arg1)
3140 || type_dependent_expression_p (arg2))
3141 return build_min_nt (code, arg1, arg2);
3142 arg1 = build_non_dependent_expr (arg1);
3143 arg2 = build_non_dependent_expr (arg2);
3146 if (code == DOTSTAR_EXPR)
3147 expr = build_m_component_ref (arg1, arg2);
3149 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3150 overloaded_p, complain);
3152 /* Check for cases such as x+y<<z which users are likely to
3153 misinterpret. But don't warn about obj << x + y, since that is a
3154 common idiom for I/O. */
3155 if (warn_parentheses
3156 && !processing_template_decl
3157 && !error_operand_p (arg1)
3158 && !error_operand_p (arg2)
3159 && (code != LSHIFT_EXPR
3160 || !CLASS_TYPE_P (TREE_TYPE (arg1))))
3161 warn_about_parentheses (code, arg1_code, orig_arg1, arg2_code, orig_arg2);
3163 if (processing_template_decl && expr != error_mark_node)
3164 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
3169 /* For the c-common bits. */
3171 build_binary_op (location_t location, enum tree_code code, tree op0, tree op1,
3172 int convert_p ATTRIBUTE_UNUSED)
3174 return cp_build_binary_op (location, code, op0, op1, tf_warning_or_error);
3178 /* Build a binary-operation expression without default conversions.
3179 CODE is the kind of expression to build.
3180 LOCATION is the location_t of the operator in the source code.
3181 This function differs from `build' in several ways:
3182 the data type of the result is computed and recorded in it,
3183 warnings are generated if arg data types are invalid,
3184 special handling for addition and subtraction of pointers is known,
3185 and some optimization is done (operations on narrow ints
3186 are done in the narrower type when that gives the same result).
3187 Constant folding is also done before the result is returned.
3189 Note that the operands will never have enumeral types
3190 because either they have just had the default conversions performed
3191 or they have both just been converted to some other type in which
3192 the arithmetic is to be done.
3194 C++: must do special pointer arithmetic when implementing
3195 multiple inheritance, and deal with pointer to member functions. */
3198 cp_build_binary_op (location_t location,
3199 enum tree_code code, tree orig_op0, tree orig_op1,
3200 tsubst_flags_t complain)
3203 enum tree_code code0, code1;
3205 const char *invalid_op_diag;
3207 /* Expression code to give to the expression when it is built.
3208 Normally this is CODE, which is what the caller asked for,
3209 but in some special cases we change it. */
3210 enum tree_code resultcode = code;
3212 /* Data type in which the computation is to be performed.
3213 In the simplest cases this is the common type of the arguments. */
3214 tree result_type = NULL;
3216 /* Nonzero means operands have already been type-converted
3217 in whatever way is necessary.
3218 Zero means they need to be converted to RESULT_TYPE. */
3221 /* Nonzero means create the expression with this type, rather than
3223 tree build_type = 0;
3225 /* Nonzero means after finally constructing the expression
3226 convert it to this type. */
3227 tree final_type = 0;
3231 /* Nonzero if this is an operation like MIN or MAX which can
3232 safely be computed in short if both args are promoted shorts.
3233 Also implies COMMON.
3234 -1 indicates a bitwise operation; this makes a difference
3235 in the exact conditions for when it is safe to do the operation
3236 in a narrower mode. */
3239 /* Nonzero if this is a comparison operation;
3240 if both args are promoted shorts, compare the original shorts.
3241 Also implies COMMON. */
3242 int short_compare = 0;
3244 /* Nonzero means set RESULT_TYPE to the common type of the args. */
3247 /* True if both operands have arithmetic type. */
3248 bool arithmetic_types_p;
3250 /* Apply default conversions. */
3254 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
3255 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
3256 || code == TRUTH_XOR_EXPR)
3258 if (!really_overloaded_fn (op0))
3259 op0 = decay_conversion (op0);
3260 if (!really_overloaded_fn (op1))
3261 op1 = decay_conversion (op1);
3265 if (!really_overloaded_fn (op0))
3266 op0 = default_conversion (op0);
3267 if (!really_overloaded_fn (op1))
3268 op1 = default_conversion (op1);
3271 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3272 STRIP_TYPE_NOPS (op0);
3273 STRIP_TYPE_NOPS (op1);
3275 /* DTRT if one side is an overloaded function, but complain about it. */
3276 if (type_unknown_p (op0))
3278 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3279 if (t != error_mark_node)
3281 if (complain & tf_error)
3282 permerror (input_location, "assuming cast to type %qT from overloaded function",
3287 if (type_unknown_p (op1))
3289 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3290 if (t != error_mark_node)
3292 if (complain & tf_error)
3293 permerror (input_location, "assuming cast to type %qT from overloaded function",
3299 type0 = TREE_TYPE (op0);
3300 type1 = TREE_TYPE (op1);
3302 /* The expression codes of the data types of the arguments tell us
3303 whether the arguments are integers, floating, pointers, etc. */
3304 code0 = TREE_CODE (type0);
3305 code1 = TREE_CODE (type1);
3307 /* If an error was already reported for one of the arguments,
3308 avoid reporting another error. */
3310 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3311 return error_mark_node;
3313 if ((invalid_op_diag
3314 = targetm.invalid_binary_op (code, type0, type1)))
3316 error (invalid_op_diag);
3317 return error_mark_node;
3323 /* Subtraction of two similar pointers.
3324 We must subtract them as integers, then divide by object size. */
3325 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3326 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3328 return pointer_diff (op0, op1, common_pointer_type (type0, type1));
3329 /* In all other cases except pointer - int, the usual arithmetic
3331 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
3336 /* The pointer - int case is just like pointer + int; fall
3339 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
3340 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
3344 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
3345 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
3346 if (processing_template_decl)
3348 result_type = TREE_TYPE (ptr_operand);
3351 return cp_pointer_int_sum (code,
3362 case TRUNC_DIV_EXPR:
3364 case FLOOR_DIV_EXPR:
3365 case ROUND_DIV_EXPR:
3366 case EXACT_DIV_EXPR:
3367 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3368 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3369 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3370 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3372 enum tree_code tcode0 = code0, tcode1 = code1;
3374 warn_for_div_by_zero (location, op1);
3376 if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE)
3377 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3378 if (tcode1 == COMPLEX_TYPE || tcode1 == VECTOR_TYPE)
3379 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3381 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
3382 resultcode = RDIV_EXPR;
3384 /* When dividing two signed integers, we have to promote to int.
3385 unless we divide by a constant != -1. Note that default
3386 conversion will have been performed on the operands at this
3387 point, so we have to dig out the original type to find out if
3389 shorten = ((TREE_CODE (op0) == NOP_EXPR
3390 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3391 || (TREE_CODE (op1) == INTEGER_CST
3392 && ! integer_all_onesp (op1)));
3401 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3402 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3403 && !VECTOR_FLOAT_TYPE_P (type0)
3404 && !VECTOR_FLOAT_TYPE_P (type1)))
3408 case TRUNC_MOD_EXPR:
3409 case FLOOR_MOD_EXPR:
3410 warn_for_div_by_zero (location, op1);
3412 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3414 /* Although it would be tempting to shorten always here, that loses
3415 on some targets, since the modulo instruction is undefined if the
3416 quotient can't be represented in the computation mode. We shorten
3417 only if unsigned or if dividing by something we know != -1. */
3418 shorten = ((TREE_CODE (op0) == NOP_EXPR
3419 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3420 || (TREE_CODE (op1) == INTEGER_CST
3421 && ! integer_all_onesp (op1)));
3426 case TRUTH_ANDIF_EXPR:
3427 case TRUTH_ORIF_EXPR:
3428 case TRUTH_AND_EXPR:
3430 result_type = boolean_type_node;
3433 /* Shift operations: result has same type as first operand;
3434 always convert second operand to int.
3435 Also set SHORT_SHIFT if shifting rightward. */
3438 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3440 result_type = type0;
3441 if (TREE_CODE (op1) == INTEGER_CST)
3443 if (tree_int_cst_lt (op1, integer_zero_node))
3445 if (complain & tf_warning)
3446 warning (0, "right shift count is negative");
3450 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0
3451 && (complain & tf_warning))
3452 warning (0, "right shift count >= width of type");
3455 /* Convert the shift-count to an integer, regardless of
3456 size of value being shifted. */
3457 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3458 op1 = cp_convert (integer_type_node, op1);
3459 /* Avoid converting op1 to result_type later. */
3465 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3467 result_type = type0;
3468 if (TREE_CODE (op1) == INTEGER_CST)
3470 if (tree_int_cst_lt (op1, integer_zero_node))
3472 if (complain & tf_warning)
3473 warning (0, "left shift count is negative");
3475 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3477 if (complain & tf_warning)
3478 warning (0, "left shift count >= width of type");
3481 /* Convert the shift-count to an integer, regardless of
3482 size of value being shifted. */
3483 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3484 op1 = cp_convert (integer_type_node, op1);
3485 /* Avoid converting op1 to result_type later. */
3492 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3494 result_type = type0;
3495 if (TREE_CODE (op1) == INTEGER_CST)
3497 if (tree_int_cst_lt (op1, integer_zero_node))
3499 if (complain & tf_warning)
3500 warning (0, (code == LROTATE_EXPR)
3501 ? G_("left rotate count is negative")
3502 : G_("right rotate count is negative"));
3504 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3506 if (complain & tf_warning)
3507 warning (0, (code == LROTATE_EXPR)
3508 ? G_("left rotate count >= width of type")
3509 : G_("right rotate count >= width of type"));
3512 /* Convert the shift-count to an integer, regardless of
3513 size of value being shifted. */
3514 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3515 op1 = cp_convert (integer_type_node, op1);
3521 if ((complain & tf_warning)
3522 && (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1)))
3523 warning (OPT_Wfloat_equal,
3524 "comparing floating point with == or != is unsafe");
3525 if ((complain & tf_warning)
3526 && ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3527 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0))))
3528 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3530 build_type = boolean_type_node;
3531 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3532 || code0 == COMPLEX_TYPE)
3533 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3534 || code1 == COMPLEX_TYPE))
3536 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3537 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3538 result_type = composite_pointer_type (type0, type1, op0, op1,
3539 "comparison", complain);
3540 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3541 && null_ptr_cst_p (op1))
3543 if (TREE_CODE (op0) == ADDR_EXPR
3544 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
3546 if (complain & tf_warning)
3547 warning (OPT_Waddress, "the address of %qD will never be NULL",
3548 TREE_OPERAND (op0, 0));
3550 result_type = type0;
3552 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3553 && null_ptr_cst_p (op0))
3555 if (TREE_CODE (op1) == ADDR_EXPR
3556 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
3558 if (complain & tf_warning)
3559 warning (OPT_Waddress, "the address of %qD will never be NULL",
3560 TREE_OPERAND (op1, 0));
3562 result_type = type1;
3564 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3566 result_type = type0;
3567 if (complain & tf_error)
3568 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3570 return error_mark_node;
3572 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3574 result_type = type1;
3575 if (complain & tf_error)
3576 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3578 return error_mark_node;
3580 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3582 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3583 == ptrmemfunc_vbit_in_delta)
3585 tree pfn0 = pfn_from_ptrmemfunc (op0);
3586 tree delta0 = delta_from_ptrmemfunc (op0);
3587 tree e1 = cp_build_binary_op (location,
3590 fold_convert (TREE_TYPE (pfn0),
3593 tree e2 = cp_build_binary_op (location,
3598 e2 = cp_build_binary_op (location,
3599 EQ_EXPR, e2, integer_zero_node,
3601 op0 = cp_build_binary_op (location,
3602 TRUTH_ANDIF_EXPR, e1, e2,
3604 op1 = cp_convert (TREE_TYPE (op0), integer_one_node);
3608 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3609 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3611 result_type = TREE_TYPE (op0);
3613 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3614 return cp_build_binary_op (location, code, op1, op0, complain);
3615 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1))
3618 /* E will be the final comparison. */
3620 /* E1 and E2 are for scratch. */
3628 type = composite_pointer_type (type0, type1, op0, op1, "comparison",
3631 if (!same_type_p (TREE_TYPE (op0), type))
3632 op0 = cp_convert_and_check (type, op0);
3633 if (!same_type_p (TREE_TYPE (op1), type))
3634 op1 = cp_convert_and_check (type, op1);
3636 if (op0 == error_mark_node || op1 == error_mark_node)
3637 return error_mark_node;
3639 if (TREE_SIDE_EFFECTS (op0))
3640 op0 = save_expr (op0);
3641 if (TREE_SIDE_EFFECTS (op1))
3642 op1 = save_expr (op1);
3644 pfn0 = pfn_from_ptrmemfunc (op0);
3645 pfn1 = pfn_from_ptrmemfunc (op1);
3646 delta0 = delta_from_ptrmemfunc (op0);
3647 delta1 = delta_from_ptrmemfunc (op1);
3648 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3649 == ptrmemfunc_vbit_in_delta)
3654 && ((op0.delta == op1.delta)
3655 || (!op0.pfn && op0.delta & 1 == 0
3656 && op1.delta & 1 == 0))
3658 The reason for the `!op0.pfn' bit is that a NULL
3659 pointer-to-member is any member with a zero PFN and
3660 LSB of the DELTA field is 0. */
3662 e1 = cp_build_binary_op (location, BIT_AND_EXPR,
3666 e1 = cp_build_binary_op (location,
3667 EQ_EXPR, e1, integer_zero_node,
3669 e2 = cp_build_binary_op (location, BIT_AND_EXPR,
3673 e2 = cp_build_binary_op (location,
3674 EQ_EXPR, e2, integer_zero_node,
3676 e1 = cp_build_binary_op (location,
3677 TRUTH_ANDIF_EXPR, e2, e1,
3679 e2 = cp_build_binary_op (location, EQ_EXPR,
3681 fold_convert (TREE_TYPE (pfn0),
3684 e2 = cp_build_binary_op (location,
3685 TRUTH_ANDIF_EXPR, e2, e1, complain);
3686 e1 = cp_build_binary_op (location,
3687 EQ_EXPR, delta0, delta1, complain);
3688 e1 = cp_build_binary_op (location,
3689 TRUTH_ORIF_EXPR, e1, e2, complain);
3696 && (!op0.pfn || op0.delta == op1.delta))
3698 The reason for the `!op0.pfn' bit is that a NULL
3699 pointer-to-member is any member with a zero PFN; the
3700 DELTA field is unspecified. */
3702 e1 = cp_build_binary_op (location,
3703 EQ_EXPR, delta0, delta1, complain);
3704 e2 = cp_build_binary_op (location,
3707 fold_convert (TREE_TYPE (pfn0),
3710 e1 = cp_build_binary_op (location,
3711 TRUTH_ORIF_EXPR, e1, e2, complain);
3713 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3714 e = cp_build_binary_op (location,
3715 TRUTH_ANDIF_EXPR, e2, e1, complain);
3716 if (code == EQ_EXPR)
3718 return cp_build_binary_op (location,
3719 EQ_EXPR, e, integer_zero_node, complain);
3723 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3724 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3726 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3727 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3735 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3736 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3738 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3739 result_type = composite_pointer_type (type0, type1, op0, op1,
3740 "comparison", complain);
3747 if (TREE_CODE (orig_op0) == STRING_CST
3748 || TREE_CODE (orig_op1) == STRING_CST)
3750 if (complain & tf_warning)
3751 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3754 build_type = boolean_type_node;
3755 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3756 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3758 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3759 result_type = composite_pointer_type (type0, type1, op0, op1,
3760 "comparison", complain);
3761 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3762 && integer_zerop (op1))
3763 result_type = type0;
3764 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3765 && integer_zerop (op0))
3766 result_type = type1;
3767 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3769 result_type = type0;
3770 if (complain & tf_error)
3771 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3773 return error_mark_node;
3775 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3777 result_type = type1;
3778 if (complain & tf_error)
3779 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3781 return error_mark_node;
3785 case UNORDERED_EXPR:
3792 build_type = integer_type_node;
3793 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3795 if (complain & tf_error)
3796 error ("unordered comparison on non-floating point argument");
3797 return error_mark_node;
3806 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3807 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3808 || code1 == COMPLEX_TYPE)))
3809 arithmetic_types_p = 1;
3812 arithmetic_types_p = 0;
3813 /* Vector arithmetic is only allowed when both sides are vectors. */
3814 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3816 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3817 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3820 binary_op_error (location, code, type0, type1);
3821 return error_mark_node;
3823 arithmetic_types_p = 1;
3826 /* Determine the RESULT_TYPE, if it is not already known. */
3828 && arithmetic_types_p
3829 && (shorten || common || short_compare))
3830 result_type = cp_common_type (type0, type1);
3834 if (complain & tf_error)
3835 error ("invalid operands of types %qT and %qT to binary %qO",
3836 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3837 return error_mark_node;
3840 /* If we're in a template, the only thing we need to know is the
3842 if (processing_template_decl)
3844 /* Since the middle-end checks the type when doing a build2, we
3845 need to build the tree in pieces. This built tree will never
3846 get out of the front-end as we replace it when instantiating
3848 tree tmp = build2 (resultcode,
3849 build_type ? build_type : result_type,
3851 TREE_OPERAND (tmp, 0) = op0;
3855 if (arithmetic_types_p)
3857 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3859 /* For certain operations (which identify themselves by shorten != 0)
3860 if both args were extended from the same smaller type,
3861 do the arithmetic in that type and then extend.
3863 shorten !=0 and !=1 indicates a bitwise operation.
3864 For them, this optimization is safe only if
3865 both args are zero-extended or both are sign-extended.
3866 Otherwise, we might change the result.
3867 E.g., (short)-1 | (unsigned short)-1 is (int)-1
3868 but calculated in (unsigned short) it would be (unsigned short)-1. */
3870 if (shorten && none_complex)
3872 final_type = result_type;
3873 result_type = shorten_binary_op (result_type, op0, op1,
3877 /* Comparison operations are shortened too but differently.
3878 They identify themselves by setting short_compare = 1. */
3882 /* Don't write &op0, etc., because that would prevent op0
3883 from being kept in a register.
3884 Instead, make copies of the our local variables and
3885 pass the copies by reference, then copy them back afterward. */
3886 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3887 enum tree_code xresultcode = resultcode;
3889 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3891 return cp_convert (boolean_type_node, val);
3892 op0 = xop0, op1 = xop1;
3894 resultcode = xresultcode;
3897 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3898 && warn_sign_compare
3899 /* Do not warn until the template is instantiated; we cannot
3900 bound the ranges of the arguments until that point. */
3901 && !processing_template_decl
3902 && (complain & tf_warning))
3904 warn_for_sign_compare (location, orig_op0, orig_op1, op0, op1,
3905 result_type, resultcode);
3909 /* Issue warnings about peculiar, but valid, uses of NULL. */
3910 if ((orig_op0 == null_node || orig_op1 == null_node)
3911 /* It's reasonable to use pointer values as operands of &&
3912 and ||, so NULL is no exception. */
3913 && code != TRUTH_ANDIF_EXPR && code != TRUTH_ORIF_EXPR
3914 && ( /* Both are NULL (or 0) and the operation was not a comparison. */
3915 (null_ptr_cst_p (orig_op0) && null_ptr_cst_p (orig_op1)
3916 && code != EQ_EXPR && code != NE_EXPR)
3917 /* Or if one of OP0 or OP1 is neither a pointer nor NULL. */
3918 || (!null_ptr_cst_p (orig_op0) && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3919 || (!null_ptr_cst_p (orig_op1) && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE))
3920 && (complain & tf_warning))
3921 /* Some sort of arithmetic operation involving NULL was
3922 performed. Note that pointer-difference and pointer-addition
3923 have already been handled above, and so we don't end up here in
3925 warning (OPT_Wpointer_arith, "NULL used in arithmetic");
3928 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3929 Then the expression will be built.
3930 It will be given type FINAL_TYPE if that is nonzero;
3931 otherwise, it will be given type RESULT_TYPE. */
3934 if (TREE_TYPE (op0) != result_type)
3935 op0 = cp_convert_and_check (result_type, op0);
3936 if (TREE_TYPE (op1) != result_type)
3937 op1 = cp_convert_and_check (result_type, op1);
3939 if (op0 == error_mark_node || op1 == error_mark_node)
3940 return error_mark_node;
3943 if (build_type == NULL_TREE)
3944 build_type = result_type;
3946 result = build2 (resultcode, build_type, op0, op1);
3947 result = fold_if_not_in_template (result);
3948 if (final_type != 0)
3949 result = cp_convert (final_type, result);
3951 if (TREE_OVERFLOW_P (result)
3952 && !TREE_OVERFLOW_P (op0)
3953 && !TREE_OVERFLOW_P (op1))
3954 overflow_warning (result);
3959 /* Return a tree for the sum or difference (RESULTCODE says which)
3960 of pointer PTROP and integer INTOP. */
3963 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
3965 tree res_type = TREE_TYPE (ptrop);
3967 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3968 in certain circumstance (when it's valid to do so). So we need
3969 to make sure it's complete. We don't need to check here, if we
3970 can actually complete it at all, as those checks will be done in
3971 pointer_int_sum() anyway. */
3972 complete_type (TREE_TYPE (res_type));
3974 return pointer_int_sum (resultcode, ptrop,
3975 fold_if_not_in_template (intop));
3978 /* Return a tree for the difference of pointers OP0 and OP1.
3979 The resulting tree has type int. */
3982 pointer_diff (tree op0, tree op1, tree ptrtype)
3985 tree restype = ptrdiff_type_node;
3986 tree target_type = TREE_TYPE (ptrtype);
3988 if (!complete_type_or_else (target_type, NULL_TREE))
3989 return error_mark_node;
3991 if (TREE_CODE (target_type) == VOID_TYPE)
3992 permerror (input_location, "ISO C++ forbids using pointer of type %<void *%> in subtraction");
3993 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3994 permerror (input_location, "ISO C++ forbids using pointer to a function in subtraction");
3995 if (TREE_CODE (target_type) == METHOD_TYPE)
3996 permerror (input_location, "ISO C++ forbids using pointer to a method in subtraction");
3998 /* First do the subtraction as integers;
3999 then drop through to build the divide operator. */
4001 op0 = cp_build_binary_op (input_location,
4003 cp_convert (restype, op0),
4004 cp_convert (restype, op1),
4005 tf_warning_or_error);
4007 /* This generates an error if op1 is a pointer to an incomplete type. */
4008 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
4009 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
4011 op1 = (TYPE_PTROB_P (ptrtype)
4012 ? size_in_bytes (target_type)
4013 : integer_one_node);
4015 /* Do the division. */
4017 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
4018 return fold_if_not_in_template (result);
4021 /* Construct and perhaps optimize a tree representation
4022 for a unary operation. CODE, a tree_code, specifies the operation
4023 and XARG is the operand. */
4026 build_x_unary_op (enum tree_code code, tree xarg, tsubst_flags_t complain)
4028 tree orig_expr = xarg;
4032 if (processing_template_decl)
4034 if (type_dependent_expression_p (xarg))
4035 return build_min_nt (code, xarg, NULL_TREE);
4037 xarg = build_non_dependent_expr (xarg);
4042 /* [expr.unary.op] says:
4044 The address of an object of incomplete type can be taken.
4046 (And is just the ordinary address operator, not an overloaded
4047 "operator &".) However, if the type is a template
4048 specialization, we must complete the type at this point so that
4049 an overloaded "operator &" will be available if required. */
4050 if (code == ADDR_EXPR
4051 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
4052 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
4053 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
4054 || (TREE_CODE (xarg) == OFFSET_REF)))
4055 /* Don't look for a function. */;
4057 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
4058 /*overloaded_p=*/NULL, complain);
4059 if (!exp && code == ADDR_EXPR)
4061 /* A pointer to member-function can be formed only by saying
4063 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
4064 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
4066 if (TREE_CODE (xarg) != OFFSET_REF
4067 || !TYPE_P (TREE_OPERAND (xarg, 0)))
4069 error ("invalid use of %qE to form a pointer-to-member-function",
4071 if (TREE_CODE (xarg) != OFFSET_REF)
4072 inform (input_location, " a qualified-id is required");
4073 return error_mark_node;
4077 error ("parentheses around %qE cannot be used to form a"
4078 " pointer-to-member-function",
4080 PTRMEM_OK_P (xarg) = 1;
4084 if (TREE_CODE (xarg) == OFFSET_REF)
4086 ptrmem = PTRMEM_OK_P (xarg);
4088 if (!ptrmem && !flag_ms_extensions
4089 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
4091 /* A single non-static member, make sure we don't allow a
4092 pointer-to-member. */
4093 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
4094 TREE_OPERAND (xarg, 0),
4095 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
4096 PTRMEM_OK_P (xarg) = ptrmem;
4099 else if (TREE_CODE (xarg) == TARGET_EXPR && (complain & tf_warning))
4100 warning (0, "taking address of temporary");
4101 exp = cp_build_unary_op (ADDR_EXPR, xarg, 0, complain);
4104 if (processing_template_decl && exp != error_mark_node)
4105 exp = build_min_non_dep (code, exp, orig_expr,
4106 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
4107 if (TREE_CODE (exp) == ADDR_EXPR)
4108 PTRMEM_OK_P (exp) = ptrmem;
4112 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
4113 constants, where a null value is represented by an INTEGER_CST of
4117 cp_truthvalue_conversion (tree expr)
4119 tree type = TREE_TYPE (expr);
4120 if (TYPE_PTRMEM_P (type))
4121 return build_binary_op (EXPR_LOCATION (expr),
4122 NE_EXPR, expr, integer_zero_node, 1);
4124 return c_common_truthvalue_conversion (input_location, expr);
4127 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
4130 condition_conversion (tree expr)
4133 if (processing_template_decl)
4135 t = perform_implicit_conversion (boolean_type_node, expr,
4136 tf_warning_or_error);
4137 t = fold_build_cleanup_point_expr (boolean_type_node, t);
4141 /* Return an ADDR_EXPR giving the address of T. This function
4142 attempts no optimizations or simplifications; it is a low-level
4146 build_address (tree t)
4150 if (error_operand_p (t) || !cxx_mark_addressable (t))
4151 return error_mark_node;
4153 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
4158 /* Return a NOP_EXPR converting EXPR to TYPE. */
4161 build_nop (tree type, tree expr)
4163 if (type == error_mark_node || error_operand_p (expr))
4165 return build1 (NOP_EXPR, type, expr);
4168 /* C++: Must handle pointers to members.
4170 Perhaps type instantiation should be extended to handle conversion
4171 from aggregates to types we don't yet know we want? (Or are those
4172 cases typically errors which should be reported?)
4174 NOCONVERT nonzero suppresses the default promotions
4175 (such as from short to int). */
4178 cp_build_unary_op (enum tree_code code, tree xarg, int noconvert,
4179 tsubst_flags_t complain)
4181 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
4184 const char *errstring = NULL;
4186 const char *invalid_op_diag;
4188 if (arg == error_mark_node)
4189 return error_mark_node;
4191 if ((invalid_op_diag
4192 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
4197 error (invalid_op_diag);
4198 return error_mark_node;
4203 case UNARY_PLUS_EXPR:
4206 int flags = WANT_ARITH | WANT_ENUM;
4207 /* Unary plus (but not unary minus) is allowed on pointers. */
4208 if (code == UNARY_PLUS_EXPR)
4209 flags |= WANT_POINTER;
4210 arg = build_expr_type_conversion (flags, arg, true);
4212 errstring = (code == NEGATE_EXPR
4213 ? "wrong type argument to unary minus"
4214 : "wrong type argument to unary plus");
4217 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4218 arg = perform_integral_promotions (arg);
4220 /* Make sure the result is not an lvalue: a unary plus or minus
4221 expression is always a rvalue. */
4228 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4232 arg = default_conversion (arg);
4234 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM
4237 errstring = "wrong type argument to bit-complement";
4238 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4239 arg = perform_integral_promotions (arg);
4243 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4244 errstring = "wrong type argument to abs";
4245 else if (!noconvert)
4246 arg = default_conversion (arg);
4250 /* Conjugating a real value is a no-op, but allow it anyway. */
4251 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4252 errstring = "wrong type argument to conjugation";
4253 else if (!noconvert)
4254 arg = default_conversion (arg);
4257 case TRUTH_NOT_EXPR:
4258 arg = perform_implicit_conversion (boolean_type_node, arg,
4260 val = invert_truthvalue (arg);
4261 if (arg != error_mark_node)
4263 errstring = "in argument to unary !";
4270 if (TREE_CODE (arg) == COMPLEX_CST)
4271 return TREE_REALPART (arg);
4272 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4274 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4275 return fold_if_not_in_template (arg);
4281 if (TREE_CODE (arg) == COMPLEX_CST)
4282 return TREE_IMAGPART (arg);
4283 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4285 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4286 return fold_if_not_in_template (arg);
4289 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4291 case PREINCREMENT_EXPR:
4292 case POSTINCREMENT_EXPR:
4293 case PREDECREMENT_EXPR:
4294 case POSTDECREMENT_EXPR:
4295 /* Handle complex lvalues (when permitted)
4296 by reduction to simpler cases. */
4298 val = unary_complex_lvalue (code, arg);
4302 /* Increment or decrement the real part of the value,
4303 and don't change the imaginary part. */
4304 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4308 arg = stabilize_reference (arg);
4309 real = cp_build_unary_op (REALPART_EXPR, arg, 1, complain);
4310 imag = cp_build_unary_op (IMAGPART_EXPR, arg, 1, complain);
4311 real = cp_build_unary_op (code, real, 1, complain);
4312 if (real == error_mark_node || imag == error_mark_node)
4313 return error_mark_node;
4314 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4318 /* Report invalid types. */
4320 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4323 if (code == PREINCREMENT_EXPR)
4324 errstring ="no pre-increment operator for type";
4325 else if (code == POSTINCREMENT_EXPR)
4326 errstring ="no post-increment operator for type";
4327 else if (code == PREDECREMENT_EXPR)
4328 errstring ="no pre-decrement operator for type";
4330 errstring ="no post-decrement operator for type";
4333 else if (arg == error_mark_node)
4334 return error_mark_node;
4336 /* Report something read-only. */
4338 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4339 || TREE_READONLY (arg))
4341 if (complain & tf_error)
4342 readonly_error (arg, ((code == PREINCREMENT_EXPR
4343 || code == POSTINCREMENT_EXPR)
4344 ? "increment" : "decrement"));
4346 return error_mark_node;
4351 tree declared_type = unlowered_expr_type (arg);
4353 argtype = TREE_TYPE (arg);
4355 /* ARM $5.2.5 last annotation says this should be forbidden. */
4356 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4358 if (complain & tf_error)
4359 permerror (input_location, (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4360 ? G_("ISO C++ forbids incrementing an enum")
4361 : G_("ISO C++ forbids decrementing an enum"));
4363 return error_mark_node;
4366 /* Compute the increment. */
4368 if (TREE_CODE (argtype) == POINTER_TYPE)
4370 tree type = complete_type (TREE_TYPE (argtype));
4372 if (!COMPLETE_OR_VOID_TYPE_P (type))
4374 if (complain & tf_error)
4375 error (((code == PREINCREMENT_EXPR
4376 || code == POSTINCREMENT_EXPR))
4377 ? G_("cannot increment a pointer to incomplete type %qT")
4378 : G_("cannot decrement a pointer to incomplete type %qT"),
4379 TREE_TYPE (argtype));
4381 return error_mark_node;
4383 else if ((pedantic || warn_pointer_arith)
4384 && !TYPE_PTROB_P (argtype))
4386 if (complain & tf_error)
4387 permerror (input_location, (code == PREINCREMENT_EXPR
4388 || code == POSTINCREMENT_EXPR)
4389 ? G_("ISO C++ forbids incrementing a pointer of type %qT")
4390 : G_("ISO C++ forbids decrementing a pointer of type %qT"),
4393 return error_mark_node;
4396 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4399 inc = integer_one_node;
4401 inc = cp_convert (argtype, inc);
4403 /* Complain about anything else that is not a true lvalue. */
4404 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4405 || code == POSTINCREMENT_EXPR)
4406 ? lv_increment : lv_decrement),
4408 return error_mark_node;
4410 /* Forbid using -- on `bool'. */
4411 if (same_type_p (declared_type, boolean_type_node))
4413 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4415 if (complain & tf_error)
4416 error ("invalid use of Boolean expression as operand "
4417 "to %<operator--%>");
4418 return error_mark_node;
4420 val = boolean_increment (code, arg);
4423 val = build2 (code, TREE_TYPE (arg), arg, inc);
4425 TREE_SIDE_EFFECTS (val) = 1;
4430 /* Note that this operation never does default_conversion
4431 regardless of NOCONVERT. */
4433 argtype = lvalue_type (arg);
4435 if (TREE_CODE (arg) == OFFSET_REF)
4438 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4440 tree type = build_pointer_type (TREE_TYPE (argtype));
4441 arg = build1 (CONVERT_EXPR, type, arg);
4444 else if (DECL_MAIN_P (arg))
4447 if (complain & tf_error)
4448 permerror (input_location, "ISO C++ forbids taking address of function %<::main%>");
4450 return error_mark_node;
4453 /* Let &* cancel out to simplify resulting code. */
4454 if (TREE_CODE (arg) == INDIRECT_REF)
4456 /* We don't need to have `current_class_ptr' wrapped in a
4457 NON_LVALUE_EXPR node. */
4458 if (arg == current_class_ref)
4459 return current_class_ptr;
4461 arg = TREE_OPERAND (arg, 0);
4462 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4464 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4465 arg = build1 (CONVERT_EXPR, type, arg);
4468 /* Don't let this be an lvalue. */
4473 /* Uninstantiated types are all functions. Taking the
4474 address of a function is a no-op, so just return the
4477 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4478 || !IDENTIFIER_OPNAME_P (arg));
4480 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4481 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4483 /* They're trying to take the address of a unique non-static
4484 member function. This is ill-formed (except in MS-land),
4485 but let's try to DTRT.
4486 Note: We only handle unique functions here because we don't
4487 want to complain if there's a static overload; non-unique
4488 cases will be handled by instantiate_type. But we need to
4489 handle this case here to allow casts on the resulting PMF.
4490 We could defer this in non-MS mode, but it's easier to give
4491 a useful error here. */
4493 /* Inside constant member functions, the `this' pointer
4494 contains an extra const qualifier. TYPE_MAIN_VARIANT
4495 is used here to remove this const from the diagnostics
4496 and the created OFFSET_REF. */
4497 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4498 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4501 if (! flag_ms_extensions)
4503 tree name = DECL_NAME (fn);
4504 if (!(complain & tf_error))
4505 return error_mark_node;
4506 else if (current_class_type
4507 && TREE_OPERAND (arg, 0) == current_class_ref)
4508 /* An expression like &memfn. */
4509 permerror (input_location, "ISO C++ forbids taking the address of an unqualified"
4510 " or parenthesized non-static member function to form"
4511 " a pointer to member function. Say %<&%T::%D%>",
4514 permerror (input_location, "ISO C++ forbids taking the address of a bound member"
4515 " function to form a pointer to member function."
4519 arg = build_offset_ref (base, fn, /*address_p=*/true);
4523 if (type_unknown_p (arg))
4524 return build1 (ADDR_EXPR, unknown_type_node, arg);
4526 /* Handle complex lvalues (when permitted)
4527 by reduction to simpler cases. */
4528 val = unary_complex_lvalue (code, arg);
4532 switch (TREE_CODE (arg))
4536 case FIX_TRUNC_EXPR:
4537 /* Even if we're not being pedantic, we cannot allow this
4538 extension when we're instantiating in a SFINAE
4540 if (! lvalue_p (arg) && complain == tf_none)
4542 if (complain & tf_error)
4543 permerror (input_location, "ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4545 return error_mark_node;
4550 arg = BASELINK_FUNCTIONS (arg);
4554 arg = OVL_CURRENT (arg);
4558 /* Turn a reference to a non-static data member into a
4559 pointer-to-member. */
4564 if (!PTRMEM_OK_P (arg))
4565 return cp_build_unary_op (code, arg, 0, complain);
4567 t = TREE_OPERAND (arg, 1);
4568 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4570 if (complain & tf_error)
4571 error ("cannot create pointer to reference member %qD", t);
4572 return error_mark_node;
4575 type = build_ptrmem_type (context_for_name_lookup (t),
4577 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4585 /* Anything not already handled and not a true memory reference
4587 if (TREE_CODE (argtype) != FUNCTION_TYPE
4588 && TREE_CODE (argtype) != METHOD_TYPE
4589 && TREE_CODE (arg) != OFFSET_REF
4590 && !lvalue_or_else (arg, lv_addressof, complain))
4591 return error_mark_node;
4593 if (argtype != error_mark_node)
4594 argtype = build_pointer_type (argtype);
4596 /* In a template, we are processing a non-dependent expression
4597 so we can just form an ADDR_EXPR with the correct type. */
4598 if (processing_template_decl || TREE_CODE (arg) != COMPONENT_REF)
4600 val = build_address (arg);
4601 if (TREE_CODE (arg) == OFFSET_REF)
4602 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4604 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4606 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4608 /* We can only get here with a single static member
4610 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4611 && DECL_STATIC_FUNCTION_P (fn));
4613 val = build_address (fn);
4614 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4615 /* Do not lose object's side effects. */
4616 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4617 TREE_OPERAND (arg, 0), val);
4619 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4621 if (complain & tf_error)
4622 error ("attempt to take address of bit-field structure member %qD",
4623 TREE_OPERAND (arg, 1));
4624 return error_mark_node;
4628 tree object = TREE_OPERAND (arg, 0);
4629 tree field = TREE_OPERAND (arg, 1);
4630 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4631 (TREE_TYPE (object), decl_type_context (field)));
4632 val = build_address (arg);
4635 if (TREE_CODE (argtype) == POINTER_TYPE
4636 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4638 build_ptrmemfunc_type (argtype);
4639 val = build_ptrmemfunc (argtype, val, 0,
4640 /*c_cast_p=*/false);
4652 argtype = TREE_TYPE (arg);
4653 return fold_if_not_in_template (build1 (code, argtype, arg));
4656 if (complain & tf_error)
4657 error ("%s", errstring);
4658 return error_mark_node;
4661 /* Hook for the c-common bits that build a unary op. */
4663 build_unary_op (location_t location ATTRIBUTE_UNUSED,
4664 enum tree_code code, tree xarg, int noconvert)
4666 return cp_build_unary_op (code, xarg, noconvert, tf_warning_or_error);
4669 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4670 for certain kinds of expressions which are not really lvalues
4671 but which we can accept as lvalues.
4673 If ARG is not a kind of expression we can handle, return
4677 unary_complex_lvalue (enum tree_code code, tree arg)
4679 /* Inside a template, making these kinds of adjustments is
4680 pointless; we are only concerned with the type of the
4682 if (processing_template_decl)
4685 /* Handle (a, b) used as an "lvalue". */
4686 if (TREE_CODE (arg) == COMPOUND_EXPR)
4688 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 1), 0,
4689 tf_warning_or_error);
4690 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4691 TREE_OPERAND (arg, 0), real_result);
4694 /* Handle (a ? b : c) used as an "lvalue". */
4695 if (TREE_CODE (arg) == COND_EXPR
4696 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4697 return rationalize_conditional_expr (code, arg, tf_warning_or_error);
4699 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4700 if (TREE_CODE (arg) == MODIFY_EXPR
4701 || TREE_CODE (arg) == PREINCREMENT_EXPR
4702 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4704 tree lvalue = TREE_OPERAND (arg, 0);
4705 if (TREE_SIDE_EFFECTS (lvalue))
4707 lvalue = stabilize_reference (lvalue);
4708 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4709 lvalue, TREE_OPERAND (arg, 1));
4711 return unary_complex_lvalue
4712 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4715 if (code != ADDR_EXPR)
4718 /* Handle (a = b) used as an "lvalue" for `&'. */
4719 if (TREE_CODE (arg) == MODIFY_EXPR
4720 || TREE_CODE (arg) == INIT_EXPR)
4722 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 0), 0,
4723 tf_warning_or_error);
4724 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4726 TREE_NO_WARNING (arg) = 1;
4730 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4731 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4732 || TREE_CODE (arg) == OFFSET_REF)
4735 /* We permit compiler to make function calls returning
4736 objects of aggregate type look like lvalues. */
4740 if (TREE_CODE (targ) == SAVE_EXPR)
4741 targ = TREE_OPERAND (targ, 0);
4743 if (TREE_CODE (targ) == CALL_EXPR && MAYBE_CLASS_TYPE_P (TREE_TYPE (targ)))
4745 if (TREE_CODE (arg) == SAVE_EXPR)
4748 targ = build_cplus_new (TREE_TYPE (arg), arg);
4749 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4752 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4753 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4754 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4757 /* Don't let anything else be handled specially. */
4761 /* Mark EXP saying that we need to be able to take the
4762 address of it; it should not be allocated in a register.
4763 Value is true if successful.
4765 C++: we do not allow `current_class_ptr' to be addressable. */
4768 cxx_mark_addressable (tree exp)
4773 switch (TREE_CODE (x))
4780 x = TREE_OPERAND (x, 0);
4784 if (x == current_class_ptr)
4786 error ("cannot take the address of %<this%>, which is an rvalue expression");
4787 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4793 /* Caller should not be trying to mark initialized
4794 constant fields addressable. */
4795 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4796 || DECL_IN_AGGR_P (x) == 0
4798 || DECL_EXTERNAL (x));
4803 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4804 && !DECL_ARTIFICIAL (x))
4806 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4809 ("address of explicit register variable %qD requested", x);
4812 else if (extra_warnings)
4814 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
4816 TREE_ADDRESSABLE (x) = 1;
4820 TREE_ADDRESSABLE (x) = 1;
4824 TREE_ADDRESSABLE (x) = 1;
4828 TREE_ADDRESSABLE (x) = 1;
4829 cxx_mark_addressable (TREE_OPERAND (x, 0));
4837 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4840 build_x_conditional_expr (tree ifexp, tree op1, tree op2,
4841 tsubst_flags_t complain)
4843 tree orig_ifexp = ifexp;
4844 tree orig_op1 = op1;
4845 tree orig_op2 = op2;
4848 if (processing_template_decl)
4850 /* The standard says that the expression is type-dependent if
4851 IFEXP is type-dependent, even though the eventual type of the
4852 expression doesn't dependent on IFEXP. */
4853 if (type_dependent_expression_p (ifexp)
4854 /* As a GNU extension, the middle operand may be omitted. */
4855 || (op1 && type_dependent_expression_p (op1))
4856 || type_dependent_expression_p (op2))
4857 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4858 ifexp = build_non_dependent_expr (ifexp);
4860 op1 = build_non_dependent_expr (op1);
4861 op2 = build_non_dependent_expr (op2);
4864 expr = build_conditional_expr (ifexp, op1, op2, complain);
4865 if (processing_template_decl && expr != error_mark_node)
4866 return build_min_non_dep (COND_EXPR, expr,
4867 orig_ifexp, orig_op1, orig_op2);
4871 /* Given a list of expressions, return a compound expression
4872 that performs them all and returns the value of the last of them. */
4874 tree build_x_compound_expr_from_list (tree list, const char *msg)
4876 tree expr = TREE_VALUE (list);
4878 if (TREE_CHAIN (list))
4881 permerror (input_location, "%s expression list treated as compound expression", msg);
4883 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4884 expr = build_x_compound_expr (expr, TREE_VALUE (list),
4885 tf_warning_or_error);
4891 /* Handle overloading of the ',' operator when needed. */
4894 build_x_compound_expr (tree op1, tree op2, tsubst_flags_t complain)
4897 tree orig_op1 = op1;
4898 tree orig_op2 = op2;
4900 if (processing_template_decl)
4902 if (type_dependent_expression_p (op1)
4903 || type_dependent_expression_p (op2))
4904 return build_min_nt (COMPOUND_EXPR, op1, op2);
4905 op1 = build_non_dependent_expr (op1);
4906 op2 = build_non_dependent_expr (op2);
4909 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4910 /*overloaded_p=*/NULL, complain);
4912 result = cp_build_compound_expr (op1, op2, complain);
4914 if (processing_template_decl && result != error_mark_node)
4915 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4920 /* Like cp_build_compound_expr, but for the c-common bits. */
4923 build_compound_expr (tree lhs, tree rhs)
4925 return cp_build_compound_expr (lhs, rhs, tf_warning_or_error);
4928 /* Build a compound expression. */
4931 cp_build_compound_expr (tree lhs, tree rhs, tsubst_flags_t complain)
4933 lhs = convert_to_void (lhs, "left-hand operand of comma", complain);
4935 if (lhs == error_mark_node || rhs == error_mark_node)
4936 return error_mark_node;
4938 if (TREE_CODE (rhs) == TARGET_EXPR)
4940 /* If the rhs is a TARGET_EXPR, then build the compound
4941 expression inside the target_expr's initializer. This
4942 helps the compiler to eliminate unnecessary temporaries. */
4943 tree init = TREE_OPERAND (rhs, 1);
4945 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4946 TREE_OPERAND (rhs, 1) = init;
4951 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4954 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
4955 casts away constness. CAST gives the type of cast. */
4958 check_for_casting_away_constness (tree src_type, tree dest_type,
4959 enum tree_code cast)
4961 /* C-style casts are allowed to cast away constness. With
4962 WARN_CAST_QUAL, we still want to issue a warning. */
4963 if (cast == CAST_EXPR && !warn_cast_qual)
4966 if (casts_away_constness (src_type, dest_type))
4970 warning (OPT_Wcast_qual,
4971 "cast from type %qT to type %qT casts away constness",
4972 src_type, dest_type);
4975 case STATIC_CAST_EXPR:
4976 error ("static_cast from type %qT to type %qT casts away constness",
4977 src_type, dest_type);
4980 case REINTERPRET_CAST_EXPR:
4981 error ("reinterpret_cast from type %qT to type %qT casts away constness",
4982 src_type, dest_type);
4989 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
4990 (another pointer-to-member type in the same hierarchy) and return
4991 the converted expression. If ALLOW_INVERSE_P is permitted, a
4992 pointer-to-derived may be converted to pointer-to-base; otherwise,
4993 only the other direction is permitted. If C_CAST_P is true, this
4994 conversion is taking place as part of a C-style cast. */
4997 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
5000 if (TYPE_PTRMEM_P (type))
5004 if (TREE_CODE (expr) == PTRMEM_CST)
5005 expr = cplus_expand_constant (expr);
5006 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
5007 TYPE_PTRMEM_CLASS_TYPE (type),
5010 if (!integer_zerop (delta))
5012 tree cond, op1, op2;
5014 cond = cp_build_binary_op (input_location,
5017 build_int_cst (TREE_TYPE (expr), -1),
5018 tf_warning_or_error);
5019 op1 = build_nop (ptrdiff_type_node, expr);
5020 op2 = cp_build_binary_op (input_location,
5021 PLUS_EXPR, op1, delta,
5022 tf_warning_or_error);
5024 expr = fold_build3 (COND_EXPR, ptrdiff_type_node, cond, op1, op2);
5028 return build_nop (type, expr);
5031 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
5032 allow_inverse_p, c_cast_p);
5035 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
5036 a version of EXPR that has TREE_OVERFLOW set if it is set in ORIG.
5037 Otherwise, return EXPR unchanged. */
5040 ignore_overflows (tree expr, tree orig)
5042 if (TREE_CODE (expr) == INTEGER_CST
5043 && CONSTANT_CLASS_P (orig)
5044 && TREE_CODE (orig) != STRING_CST
5045 && TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig))
5047 if (!TREE_OVERFLOW (orig))
5048 /* Ensure constant sharing. */
5049 expr = build_int_cst_wide (TREE_TYPE (expr),
5050 TREE_INT_CST_LOW (expr),
5051 TREE_INT_CST_HIGH (expr));
5054 /* Avoid clobbering a shared constant. */
5055 expr = copy_node (expr);
5056 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
5062 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
5063 this static_cast is being attempted as one of the possible casts
5064 allowed by a C-style cast. (In that case, accessibility of base
5065 classes is not considered, and it is OK to cast away
5066 constness.) Return the result of the cast. *VALID_P is set to
5067 indicate whether or not the cast was valid. */
5070 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
5071 bool *valid_p, tsubst_flags_t complain)
5077 /* Assume the cast is valid. */
5080 intype = TREE_TYPE (expr);
5082 /* Save casted types in the function's used types hash table. */
5083 used_types_insert (type);
5085 /* [expr.static.cast]
5087 An lvalue of type "cv1 B", where B is a class type, can be cast
5088 to type "reference to cv2 D", where D is a class derived (clause
5089 _class.derived_) from B, if a valid standard conversion from
5090 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
5091 same cv-qualification as, or greater cv-qualification than, cv1,
5092 and B is not a virtual base class of D. */
5093 /* We check this case before checking the validity of "TYPE t =
5094 EXPR;" below because for this case:
5097 struct D : public B { D(const B&); };
5099 void f() { static_cast<const D&>(b); }
5101 we want to avoid constructing a new D. The standard is not
5102 completely clear about this issue, but our interpretation is
5103 consistent with other compilers. */
5104 if (TREE_CODE (type) == REFERENCE_TYPE
5105 && CLASS_TYPE_P (TREE_TYPE (type))
5106 && CLASS_TYPE_P (intype)
5107 && real_lvalue_p (expr)
5108 && DERIVED_FROM_P (intype, TREE_TYPE (type))
5109 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
5110 build_pointer_type (TYPE_MAIN_VARIANT
5111 (TREE_TYPE (type))))
5113 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5117 /* There is a standard conversion from "D*" to "B*" even if "B"
5118 is ambiguous or inaccessible. If this is really a
5119 static_cast, then we check both for inaccessibility and
5120 ambiguity. However, if this is a static_cast being performed
5121 because the user wrote a C-style cast, then accessibility is
5123 base = lookup_base (TREE_TYPE (type), intype,
5124 c_cast_p ? ba_unique : ba_check,
5127 /* Convert from "B*" to "D*". This function will check that "B"
5128 is not a virtual base of "D". */
5129 expr = build_base_path (MINUS_EXPR, build_address (expr),
5130 base, /*nonnull=*/false);
5131 /* Convert the pointer to a reference -- but then remember that
5132 there are no expressions with reference type in C++. */
5133 return convert_from_reference (build_nop (type, expr));
5138 /* [expr.static.cast]
5140 An expression e can be explicitly converted to a type T using a
5141 static_cast of the form static_cast<T>(e) if the declaration T
5142 t(e);" is well-formed, for some invented temporary variable
5144 result = perform_direct_initialization_if_possible (type, expr,
5145 c_cast_p, complain);
5148 result = convert_from_reference (result);
5150 /* Ignore any integer overflow caused by the cast. */
5151 result = ignore_overflows (result, orig);
5153 /* [expr.static.cast]
5155 If T is a reference type, the result is an lvalue; otherwise,
5156 the result is an rvalue. */
5157 if (TREE_CODE (type) != REFERENCE_TYPE)
5158 result = rvalue (result);
5162 /* [expr.static.cast]
5164 Any expression can be explicitly converted to type cv void. */
5165 if (TREE_CODE (type) == VOID_TYPE)
5166 return convert_to_void (expr, /*implicit=*/NULL, complain);
5168 /* [expr.static.cast]
5170 The inverse of any standard conversion sequence (clause _conv_),
5171 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
5172 (_conv.array_), function-to-pointer (_conv.func_), and boolean
5173 (_conv.bool_) conversions, can be performed explicitly using
5174 static_cast subject to the restriction that the explicit
5175 conversion does not cast away constness (_expr.const.cast_), and
5176 the following additional rules for specific cases: */
5177 /* For reference, the conversions not excluded are: integral
5178 promotions, floating point promotion, integral conversions,
5179 floating point conversions, floating-integral conversions,
5180 pointer conversions, and pointer to member conversions. */
5183 A value of integral _or enumeration_ type can be explicitly
5184 converted to an enumeration type. */
5185 /* The effect of all that is that any conversion between any two
5186 types which are integral, floating, or enumeration types can be
5188 if ((INTEGRAL_TYPE_P (type) || SCALAR_FLOAT_TYPE_P (type))
5189 && (INTEGRAL_TYPE_P (intype) || SCALAR_FLOAT_TYPE_P (intype)))
5191 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
5193 /* Ignore any integer overflow caused by the cast. */
5194 expr = ignore_overflows (expr, orig);
5198 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
5199 && CLASS_TYPE_P (TREE_TYPE (type))
5200 && CLASS_TYPE_P (TREE_TYPE (intype))
5201 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
5202 (TREE_TYPE (intype))),
5203 build_pointer_type (TYPE_MAIN_VARIANT
5204 (TREE_TYPE (type)))))
5209 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5210 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
5211 c_cast_p ? ba_unique : ba_check,
5213 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
5216 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5217 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5224 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
5225 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
5227 if (TYPE_PTRMEM_P (type))
5229 t1 = (build_ptrmem_type
5231 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
5232 t2 = (build_ptrmem_type
5234 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
5241 if (can_convert (t1, t2) || can_convert (t2, t1))
5244 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5245 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
5250 /* [expr.static.cast]
5252 An rvalue of type "pointer to cv void" can be explicitly
5253 converted to a pointer to object type. A value of type pointer
5254 to object converted to "pointer to cv void" and back to the
5255 original pointer type will have its original value. */
5256 if (TREE_CODE (intype) == POINTER_TYPE
5257 && VOID_TYPE_P (TREE_TYPE (intype))
5258 && TYPE_PTROB_P (type))
5261 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5262 return build_nop (type, expr);
5266 return error_mark_node;
5269 /* Return an expression representing static_cast<TYPE>(EXPR). */
5272 build_static_cast (tree type, tree expr, tsubst_flags_t complain)
5277 if (type == error_mark_node || expr == error_mark_node)
5278 return error_mark_node;
5280 if (processing_template_decl)
5282 expr = build_min (STATIC_CAST_EXPR, type, expr);
5283 /* We don't know if it will or will not have side effects. */
5284 TREE_SIDE_EFFECTS (expr) = 1;
5285 return convert_from_reference (expr);
5288 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5289 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5290 if (TREE_CODE (type) != REFERENCE_TYPE
5291 && TREE_CODE (expr) == NOP_EXPR
5292 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5293 expr = TREE_OPERAND (expr, 0);
5295 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p,
5300 if (complain & tf_error)
5301 error ("invalid static_cast from type %qT to type %qT",
5302 TREE_TYPE (expr), type);
5303 return error_mark_node;
5306 /* EXPR is an expression with member function or pointer-to-member
5307 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5308 not permitted by ISO C++, but we accept it in some modes. If we
5309 are not in one of those modes, issue a diagnostic. Return the
5310 converted expression. */
5313 convert_member_func_to_ptr (tree type, tree expr)
5318 intype = TREE_TYPE (expr);
5319 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
5320 || TREE_CODE (intype) == METHOD_TYPE);
5322 if (pedantic || warn_pmf2ptr)
5323 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpmf_conversions,
5324 "converting from %qT to %qT", intype, type);
5326 if (TREE_CODE (intype) == METHOD_TYPE)
5327 expr = build_addr_func (expr);
5328 else if (TREE_CODE (expr) == PTRMEM_CST)
5329 expr = build_address (PTRMEM_CST_MEMBER (expr));
5332 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
5333 decl = build_address (decl);
5334 expr = get_member_function_from_ptrfunc (&decl, expr);
5337 return build_nop (type, expr);
5340 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5341 If C_CAST_P is true, this reinterpret cast is being done as part of
5342 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5343 indicate whether or not reinterpret_cast was valid. */
5346 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5347 bool *valid_p, tsubst_flags_t complain)
5351 /* Assume the cast is invalid. */
5355 if (type == error_mark_node || error_operand_p (expr))
5356 return error_mark_node;
5358 intype = TREE_TYPE (expr);
5360 /* Save casted types in the function's used types hash table. */
5361 used_types_insert (type);
5363 /* [expr.reinterpret.cast]
5364 An lvalue expression of type T1 can be cast to the type
5365 "reference to T2" if an expression of type "pointer to T1" can be
5366 explicitly converted to the type "pointer to T2" using a
5367 reinterpret_cast. */
5368 if (TREE_CODE (type) == REFERENCE_TYPE)
5370 if (! real_lvalue_p (expr))
5372 if (complain & tf_error)
5373 error ("invalid cast of an rvalue expression of type "
5376 return error_mark_node;
5379 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5380 "B" are related class types; the reinterpret_cast does not
5381 adjust the pointer. */
5382 if (TYPE_PTR_P (intype)
5383 && (complain & tf_warning)
5384 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5385 COMPARE_BASE | COMPARE_DERIVED)))
5386 warning (0, "casting %qT to %qT does not dereference pointer",
5389 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
5390 if (expr != error_mark_node)
5391 expr = build_reinterpret_cast_1
5392 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5394 if (expr != error_mark_node)
5395 expr = cp_build_indirect_ref (expr, 0, complain);
5399 /* As a G++ extension, we consider conversions from member
5400 functions, and pointers to member functions to
5401 pointer-to-function and pointer-to-void types. If
5402 -Wno-pmf-conversions has not been specified,
5403 convert_member_func_to_ptr will issue an error message. */
5404 if ((TYPE_PTRMEMFUNC_P (intype)
5405 || TREE_CODE (intype) == METHOD_TYPE)
5406 && TYPE_PTR_P (type)
5407 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5408 || VOID_TYPE_P (TREE_TYPE (type))))
5409 return convert_member_func_to_ptr (type, expr);
5411 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5412 array-to-pointer, and function-to-pointer conversions are
5414 expr = decay_conversion (expr);
5416 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5417 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5418 if (TREE_CODE (expr) == NOP_EXPR
5419 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5420 expr = TREE_OPERAND (expr, 0);
5422 if (error_operand_p (expr))
5423 return error_mark_node;
5425 intype = TREE_TYPE (expr);
5427 /* [expr.reinterpret.cast]
5428 A pointer can be converted to any integral type large enough to
5430 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5432 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5434 if (complain & tf_error)
5435 permerror (input_location, "cast from %qT to %qT loses precision",
5438 return error_mark_node;
5441 /* [expr.reinterpret.cast]
5442 A value of integral or enumeration type can be explicitly
5443 converted to a pointer. */
5444 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5447 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5448 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5449 return fold_if_not_in_template (build_nop (type, expr));
5450 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5451 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5456 check_for_casting_away_constness (intype, type, REINTERPRET_CAST_EXPR);
5457 /* Warn about possible alignment problems. */
5458 if (STRICT_ALIGNMENT && warn_cast_align
5459 && (complain & tf_warning)
5460 && !VOID_TYPE_P (type)
5461 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5462 && COMPLETE_TYPE_P (TREE_TYPE (type))
5463 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5464 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5465 warning (OPT_Wcast_align, "cast from %qT to %qT "
5466 "increases required alignment of target type", intype, type);
5468 /* We need to strip nops here, because the front end likes to
5469 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5471 if (warn_strict_aliasing <= 2)
5472 strict_aliasing_warning (intype, type, sexpr);
5474 return fold_if_not_in_template (build_nop (type, expr));
5476 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5477 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5479 if (pedantic && (complain & tf_warning))
5480 /* Only issue a warning, as we have always supported this
5481 where possible, and it is necessary in some cases. DR 195
5482 addresses this issue, but as of 2004/10/26 is still in
5484 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5485 return fold_if_not_in_template (build_nop (type, expr));
5487 else if (TREE_CODE (type) == VECTOR_TYPE)
5488 return fold_if_not_in_template (convert_to_vector (type, expr));
5489 else if (TREE_CODE (intype) == VECTOR_TYPE && INTEGRAL_TYPE_P (type))
5490 return fold_if_not_in_template (convert_to_integer (type, expr));
5495 if (complain & tf_error)
5496 error ("invalid cast from type %qT to type %qT", intype, type);
5497 return error_mark_node;
5500 return cp_convert (type, expr);
5504 build_reinterpret_cast (tree type, tree expr, tsubst_flags_t complain)
5506 if (type == error_mark_node || expr == error_mark_node)
5507 return error_mark_node;
5509 if (processing_template_decl)
5511 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5513 if (!TREE_SIDE_EFFECTS (t)
5514 && type_dependent_expression_p (expr))
5515 /* There might turn out to be side effects inside expr. */
5516 TREE_SIDE_EFFECTS (t) = 1;
5517 return convert_from_reference (t);
5520 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5521 /*valid_p=*/NULL, complain);
5524 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5525 return an appropriate expression. Otherwise, return
5526 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5527 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5528 performing a C-style cast, its value upon return will indicate
5529 whether or not the conversion succeeded. */
5532 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5536 tree reference_type;
5538 /* Callers are responsible for handling error_mark_node as a
5539 destination type. */
5540 gcc_assert (dst_type != error_mark_node);
5541 /* In a template, callers should be building syntactic
5542 representations of casts, not using this machinery. */
5543 gcc_assert (!processing_template_decl);
5545 /* Assume the conversion is invalid. */
5549 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5552 error ("invalid use of const_cast with type %qT, "
5553 "which is not a pointer, "
5554 "reference, nor a pointer-to-data-member type", dst_type);
5555 return error_mark_node;
5558 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5561 error ("invalid use of const_cast with type %qT, which is a pointer "
5562 "or reference to a function type", dst_type);
5563 return error_mark_node;
5566 /* Save casted types in the function's used types hash table. */
5567 used_types_insert (dst_type);
5569 src_type = TREE_TYPE (expr);
5570 /* Expressions do not really have reference types. */
5571 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5572 src_type = TREE_TYPE (src_type);
5574 /* [expr.const.cast]
5576 An lvalue of type T1 can be explicitly converted to an lvalue of
5577 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5578 types) if a pointer to T1 can be explicitly converted to the type
5579 pointer to T2 using a const_cast. */
5580 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5582 reference_type = dst_type;
5583 if (! real_lvalue_p (expr))
5586 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5587 src_type, dst_type);
5588 return error_mark_node;
5590 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5591 src_type = build_pointer_type (src_type);
5595 reference_type = NULL_TREE;
5596 /* If the destination type is not a reference type, the
5597 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5598 conversions are performed. */
5599 src_type = type_decays_to (src_type);
5600 if (src_type == error_mark_node)
5601 return error_mark_node;
5604 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5605 && comp_ptr_ttypes_const (dst_type, src_type))
5610 /* This cast is actually a C-style cast. Issue a warning if
5611 the user is making a potentially unsafe cast. */
5612 check_for_casting_away_constness (src_type, dst_type, CAST_EXPR);
5616 expr = cp_build_unary_op (ADDR_EXPR, expr, 0,
5617 complain? tf_warning_or_error : tf_none);
5618 expr = build_nop (reference_type, expr);
5619 return convert_from_reference (expr);
5623 expr = decay_conversion (expr);
5624 /* build_c_cast puts on a NOP_EXPR to make the result not an
5625 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5626 non-lvalue context. */
5627 if (TREE_CODE (expr) == NOP_EXPR
5628 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5629 expr = TREE_OPERAND (expr, 0);
5630 return build_nop (dst_type, expr);
5635 error ("invalid const_cast from type %qT to type %qT",
5636 src_type, dst_type);
5637 return error_mark_node;
5641 build_const_cast (tree type, tree expr, tsubst_flags_t complain)
5643 if (type == error_mark_node || error_operand_p (expr))
5644 return error_mark_node;
5646 if (processing_template_decl)
5648 tree t = build_min (CONST_CAST_EXPR, type, expr);
5650 if (!TREE_SIDE_EFFECTS (t)
5651 && type_dependent_expression_p (expr))
5652 /* There might turn out to be side effects inside expr. */
5653 TREE_SIDE_EFFECTS (t) = 1;
5654 return convert_from_reference (t);
5657 return build_const_cast_1 (type, expr, complain & tf_error,
5661 /* Like cp_build_c_cast, but for the c-common bits. */
5664 build_c_cast (tree type, tree expr)
5666 return cp_build_c_cast (type, expr, tf_warning_or_error);
5669 /* Build an expression representing an explicit C-style cast to type
5670 TYPE of expression EXPR. */
5673 cp_build_c_cast (tree type, tree expr, tsubst_flags_t complain)
5679 if (type == error_mark_node || error_operand_p (expr))
5680 return error_mark_node;
5682 if (processing_template_decl)
5684 tree t = build_min (CAST_EXPR, type,
5685 tree_cons (NULL_TREE, value, NULL_TREE));
5686 /* We don't know if it will or will not have side effects. */
5687 TREE_SIDE_EFFECTS (t) = 1;
5688 return convert_from_reference (t);
5691 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5692 'Class') should always be retained, because this information aids
5693 in method lookup. */
5694 if (objc_is_object_ptr (type)
5695 && objc_is_object_ptr (TREE_TYPE (expr)))
5696 return build_nop (type, expr);
5698 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5699 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5700 if (TREE_CODE (type) != REFERENCE_TYPE
5701 && TREE_CODE (value) == NOP_EXPR
5702 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5703 value = TREE_OPERAND (value, 0);
5705 if (TREE_CODE (type) == ARRAY_TYPE)
5707 /* Allow casting from T1* to T2[] because Cfront allows it.
5708 NIHCL uses it. It is not valid ISO C++ however. */
5709 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5711 if (complain & tf_error)
5712 permerror (input_location, "ISO C++ forbids casting to an array type %qT", type);
5714 return error_mark_node;
5715 type = build_pointer_type (TREE_TYPE (type));
5719 if (complain & tf_error)
5720 error ("ISO C++ forbids casting to an array type %qT", type);
5721 return error_mark_node;
5725 if (TREE_CODE (type) == FUNCTION_TYPE
5726 || TREE_CODE (type) == METHOD_TYPE)
5728 if (complain & tf_error)
5729 error ("invalid cast to function type %qT", type);
5730 return error_mark_node;
5733 /* A C-style cast can be a const_cast. */
5734 result = build_const_cast_1 (type, value, /*complain=*/false,
5739 /* Or a static cast. */
5740 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5741 &valid_p, complain);
5742 /* Or a reinterpret_cast. */
5744 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5745 &valid_p, complain);
5746 /* The static_cast or reinterpret_cast may be followed by a
5749 /* A valid cast may result in errors if, for example, a
5750 conversion to am ambiguous base class is required. */
5751 && !error_operand_p (result))
5755 /* Non-class rvalues always have cv-unqualified type. */
5756 if (!CLASS_TYPE_P (type))
5757 type = TYPE_MAIN_VARIANT (type);
5758 result_type = TREE_TYPE (result);
5759 if (!CLASS_TYPE_P (result_type))
5760 result_type = TYPE_MAIN_VARIANT (result_type);
5761 /* If the type of RESULT does not match TYPE, perform a
5762 const_cast to make it match. If the static_cast or
5763 reinterpret_cast succeeded, we will differ by at most
5764 cv-qualification, so the follow-on const_cast is guaranteed
5766 if (!same_type_p (non_reference (type), non_reference (result_type)))
5768 result = build_const_cast_1 (type, result, false, &valid_p);
5769 gcc_assert (valid_p);
5774 return error_mark_node;
5777 /* For use from the C common bits. */
5779 build_modify_expr (location_t location ATTRIBUTE_UNUSED,
5780 tree lhs, enum tree_code modifycode, tree rhs)
5782 return cp_build_modify_expr (lhs, modifycode, rhs, tf_warning_or_error);
5785 /* Build an assignment expression of lvalue LHS from value RHS.
5786 MODIFYCODE is the code for a binary operator that we use
5787 to combine the old value of LHS with RHS to get the new value.
5788 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5790 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5793 cp_build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
5794 tsubst_flags_t complain)
5798 tree lhstype = TREE_TYPE (lhs);
5799 tree olhstype = lhstype;
5800 bool plain_assign = (modifycode == NOP_EXPR);
5802 /* Avoid duplicate error messages from operands that had errors. */
5803 if (error_operand_p (lhs) || error_operand_p (rhs))
5804 return error_mark_node;
5806 /* Handle control structure constructs used as "lvalues". */
5807 switch (TREE_CODE (lhs))
5809 /* Handle --foo = 5; as these are valid constructs in C++. */
5810 case PREDECREMENT_EXPR:
5811 case PREINCREMENT_EXPR:
5812 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5813 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5814 stabilize_reference (TREE_OPERAND (lhs, 0)),
5815 TREE_OPERAND (lhs, 1));
5816 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0),
5817 modifycode, rhs, complain);
5818 if (newrhs == error_mark_node)
5819 return error_mark_node;
5820 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5822 /* Handle (a, b) used as an "lvalue". */
5824 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 1),
5825 modifycode, rhs, complain);
5826 if (newrhs == error_mark_node)
5827 return error_mark_node;
5828 return build2 (COMPOUND_EXPR, lhstype,
5829 TREE_OPERAND (lhs, 0), newrhs);
5832 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5833 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5834 stabilize_reference (TREE_OPERAND (lhs, 0)),
5835 TREE_OPERAND (lhs, 1));
5836 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs,
5838 if (newrhs == error_mark_node)
5839 return error_mark_node;
5840 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5844 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
5845 when neither operand has side-effects. */
5846 if (!lvalue_or_else (lhs, lv_assign, complain))
5847 return error_mark_node;
5849 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
5850 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
5852 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
5853 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
5855 TREE_OPERAND (lhs, 0),
5856 TREE_OPERAND (lhs, 1)),
5857 TREE_OPERAND (lhs, 0),
5858 TREE_OPERAND (lhs, 1));
5861 /* Handle (a ? b : c) used as an "lvalue". */
5864 /* Produce (a ? (b = rhs) : (c = rhs))
5865 except that the RHS goes through a save-expr
5866 so the code to compute it is only emitted once. */
5868 tree preeval = NULL_TREE;
5870 if (VOID_TYPE_P (TREE_TYPE (rhs)))
5872 if (complain & tf_error)
5873 error ("void value not ignored as it ought to be");
5874 return error_mark_node;
5877 rhs = stabilize_expr (rhs, &preeval);
5879 /* Check this here to avoid odd errors when trying to convert
5880 a throw to the type of the COND_EXPR. */
5881 if (!lvalue_or_else (lhs, lv_assign, complain))
5882 return error_mark_node;
5884 cond = build_conditional_expr
5885 (TREE_OPERAND (lhs, 0),
5886 cp_build_modify_expr (TREE_OPERAND (lhs, 1),
5887 modifycode, rhs, complain),
5888 cp_build_modify_expr (TREE_OPERAND (lhs, 2),
5889 modifycode, rhs, complain),
5892 if (cond == error_mark_node)
5894 /* Make sure the code to compute the rhs comes out
5895 before the split. */
5897 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5905 if (modifycode == INIT_EXPR)
5907 if (TREE_CODE (rhs) == CONSTRUCTOR)
5909 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5910 /* Call convert to generate an error; see PR 11063. */
5911 rhs = convert (lhstype, rhs);
5912 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
5913 TREE_SIDE_EFFECTS (result) = 1;
5916 else if (! MAYBE_CLASS_TYPE_P (lhstype))
5917 /* Do the default thing. */;
5920 result = build_special_member_call (lhs, complete_ctor_identifier,
5921 build_tree_list (NULL_TREE, rhs),
5922 lhstype, LOOKUP_NORMAL,
5924 if (result == NULL_TREE)
5925 return error_mark_node;
5931 lhs = require_complete_type (lhs);
5932 if (lhs == error_mark_node)
5933 return error_mark_node;
5935 if (modifycode == NOP_EXPR)
5937 /* `operator=' is not an inheritable operator. */
5938 if (! MAYBE_CLASS_TYPE_P (lhstype))
5939 /* Do the default thing. */;
5942 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5943 lhs, rhs, make_node (NOP_EXPR),
5944 /*overloaded_p=*/NULL,
5946 if (result == NULL_TREE)
5947 return error_mark_node;
5954 /* A binary op has been requested. Combine the old LHS
5955 value with the RHS producing the value we should actually
5956 store into the LHS. */
5957 gcc_assert (!((TREE_CODE (lhstype) == REFERENCE_TYPE
5958 && MAYBE_CLASS_TYPE_P (TREE_TYPE (lhstype)))
5959 || MAYBE_CLASS_TYPE_P (lhstype)));
5961 lhs = stabilize_reference (lhs);
5962 newrhs = cp_build_binary_op (input_location,
5963 modifycode, lhs, rhs,
5965 if (newrhs == error_mark_node)
5967 if (complain & tf_error)
5968 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
5969 TREE_TYPE (lhs), TREE_TYPE (rhs));
5970 return error_mark_node;
5973 /* Now it looks like a plain assignment. */
5974 modifycode = NOP_EXPR;
5976 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
5977 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
5980 /* The left-hand side must be an lvalue. */
5981 if (!lvalue_or_else (lhs, lv_assign, complain))
5982 return error_mark_node;
5984 /* Warn about modifying something that is `const'. Don't warn if
5985 this is initialization. */
5986 if (modifycode != INIT_EXPR
5987 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5988 /* Functions are not modifiable, even though they are
5990 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5991 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5992 /* If it's an aggregate and any field is const, then it is
5993 effectively const. */
5994 || (CLASS_TYPE_P (lhstype)
5995 && C_TYPE_FIELDS_READONLY (lhstype))))
5997 if (complain & tf_error)
5998 readonly_error (lhs, "assignment");
6000 return error_mark_node;
6003 /* If storing into a structure or union member, it may have been given a
6004 lowered bitfield type. We need to convert to the declared type first,
6005 so retrieve it now. */
6007 olhstype = unlowered_expr_type (lhs);
6009 /* Convert new value to destination type. */
6011 if (TREE_CODE (lhstype) == ARRAY_TYPE)
6015 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
6016 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
6018 if (complain & tf_error)
6019 error ("incompatible types in assignment of %qT to %qT",
6020 TREE_TYPE (rhs), lhstype);
6021 return error_mark_node;
6024 /* Allow array assignment in compiler-generated code. */
6025 if (! DECL_ARTIFICIAL (current_function_decl))
6027 /* This routine is used for both initialization and assignment.
6028 Make sure the diagnostic message differentiates the context. */
6029 if (complain & tf_error)
6031 if (modifycode == INIT_EXPR)
6032 error ("array used as initializer");
6034 error ("invalid array assignment");
6036 return error_mark_node;
6039 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
6040 ? 1 + (modifycode != INIT_EXPR): 0;
6041 return build_vec_init (lhs, NULL_TREE, newrhs,
6042 /*explicit_value_init_p=*/false,
6043 from_array, complain);
6046 if (modifycode == INIT_EXPR)
6047 newrhs = convert_for_initialization (lhs, olhstype, newrhs, LOOKUP_NORMAL,
6048 "initialization", NULL_TREE, 0,
6051 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
6052 NULL_TREE, 0, complain);
6054 if (!same_type_p (lhstype, olhstype))
6055 newrhs = cp_convert_and_check (lhstype, newrhs);
6057 if (modifycode != INIT_EXPR)
6059 if (TREE_CODE (newrhs) == CALL_EXPR
6060 && TYPE_NEEDS_CONSTRUCTING (lhstype))
6061 newrhs = build_cplus_new (lhstype, newrhs);
6063 /* Can't initialize directly from a TARGET_EXPR, since that would
6064 cause the lhs to be constructed twice, and possibly result in
6065 accidental self-initialization. So we force the TARGET_EXPR to be
6066 expanded without a target. */
6067 if (TREE_CODE (newrhs) == TARGET_EXPR)
6068 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
6069 TREE_OPERAND (newrhs, 0));
6072 if (newrhs == error_mark_node)
6073 return error_mark_node;
6075 if (c_dialect_objc () && flag_objc_gc)
6077 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
6083 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
6084 lhstype, lhs, newrhs);
6086 TREE_SIDE_EFFECTS (result) = 1;
6088 TREE_NO_WARNING (result) = 1;
6094 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6095 tsubst_flags_t complain)
6097 if (processing_template_decl)
6098 return build_min_nt (MODOP_EXPR, lhs,
6099 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
6101 if (modifycode != NOP_EXPR)
6103 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
6104 make_node (modifycode),
6105 /*overloaded_p=*/NULL,
6109 TREE_NO_WARNING (rval) = 1;
6113 return cp_build_modify_expr (lhs, modifycode, rhs, complain);
6116 /* Helper function for get_delta_difference which assumes FROM is a base
6117 class of TO. Returns a delta for the conversion of pointer-to-member
6118 of FROM to pointer-to-member of TO. If the conversion is invalid,
6119 returns zero. If FROM is not a base class of TO, returns NULL_TREE.
6120 If C_CAST_P is true, this conversion is taking place as part of a C-style
6124 get_delta_difference_1 (tree from, tree to, bool c_cast_p)
6129 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
6130 if (kind == bk_inaccessible || kind == bk_ambig)
6132 error (" in pointer to member function conversion");
6133 return size_zero_node;
6137 if (kind != bk_via_virtual)
6138 return BINFO_OFFSET (binfo);
6140 /* FROM is a virtual base class of TO. Issue an error or warning
6141 depending on whether or not this is a reinterpret cast. */
6143 error ("pointer to member conversion via virtual base %qT",
6144 BINFO_TYPE (binfo_from_vbase (binfo)));
6146 return size_zero_node;
6153 /* Get difference in deltas for different pointer to member function
6154 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
6155 the conversion is invalid, the constant is zero. If
6156 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
6157 If C_CAST_P is true this conversion is taking place as part of a
6160 Note that the naming of FROM and TO is kind of backwards; the return
6161 value is what we add to a TO in order to get a FROM. They are named
6162 this way because we call this function to find out how to convert from
6163 a pointer to member of FROM to a pointer to member of TO. */
6166 get_delta_difference (tree from, tree to,
6167 bool allow_inverse_p,
6172 if (same_type_ignoring_top_level_qualifiers_p (from, to))
6173 /* Pointer to member of incomplete class is permitted*/
6174 result = size_zero_node;
6176 result = get_delta_difference_1 (from, to, c_cast_p);
6180 if (!allow_inverse_p)
6182 error_not_base_type (from, to);
6183 error (" in pointer to member conversion");
6184 result = size_zero_node;
6188 result = get_delta_difference_1 (to, from, c_cast_p);
6191 result = size_diffop (size_zero_node, result);
6194 error_not_base_type (from, to);
6195 error (" in pointer to member conversion");
6196 result = size_zero_node;
6201 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
6205 /* Return a constructor for the pointer-to-member-function TYPE using
6206 the other components as specified. */
6209 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
6214 VEC(constructor_elt, gc) *v;
6216 /* Pull the FIELD_DECLs out of the type. */
6217 pfn_field = TYPE_FIELDS (type);
6218 delta_field = TREE_CHAIN (pfn_field);
6220 /* Make sure DELTA has the type we want. */
6221 delta = convert_and_check (delta_type_node, delta);
6223 /* Convert to the correct target type if necessary. */
6224 pfn = fold_convert (TREE_TYPE (pfn_field), pfn);
6226 /* Finish creating the initializer. */
6227 v = VEC_alloc(constructor_elt, gc, 2);
6228 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
6229 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
6230 u = build_constructor (type, v);
6231 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
6232 TREE_STATIC (u) = (TREE_CONSTANT (u)
6233 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
6235 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
6240 /* Build a constructor for a pointer to member function. It can be
6241 used to initialize global variables, local variable, or used
6242 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
6245 If FORCE is nonzero, then force this conversion, even if
6246 we would rather not do it. Usually set when using an explicit
6247 cast. A C-style cast is being processed iff C_CAST_P is true.
6249 Return error_mark_node, if something goes wrong. */
6252 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
6258 if (error_operand_p (pfn))
6259 return error_mark_node;
6261 pfn_type = TREE_TYPE (pfn);
6262 to_type = build_ptrmemfunc_type (type);
6264 /* Handle multiple conversions of pointer to member functions. */
6265 if (TYPE_PTRMEMFUNC_P (pfn_type))
6267 tree delta = NULL_TREE;
6268 tree npfn = NULL_TREE;
6272 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
6273 error ("invalid conversion to type %qT from type %qT",
6276 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
6277 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
6281 /* We don't have to do any conversion to convert a
6282 pointer-to-member to its own type. But, we don't want to
6283 just return a PTRMEM_CST if there's an explicit cast; that
6284 cast should make the expression an invalid template argument. */
6285 if (TREE_CODE (pfn) != PTRMEM_CST)
6287 if (same_type_p (to_type, pfn_type))
6289 else if (integer_zerop (n))
6290 return build_reinterpret_cast (to_type, pfn,
6291 tf_warning_or_error);
6294 if (TREE_SIDE_EFFECTS (pfn))
6295 pfn = save_expr (pfn);
6297 /* Obtain the function pointer and the current DELTA. */
6298 if (TREE_CODE (pfn) == PTRMEM_CST)
6299 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
6302 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
6303 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
6306 /* Just adjust the DELTA field. */
6307 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6308 (TREE_TYPE (delta), ptrdiff_type_node));
6309 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
6310 n = cp_build_binary_op (input_location,
6311 LSHIFT_EXPR, n, integer_one_node,
6312 tf_warning_or_error);
6313 delta = cp_build_binary_op (input_location,
6314 PLUS_EXPR, delta, n, tf_warning_or_error);
6315 return build_ptrmemfunc1 (to_type, delta, npfn);
6318 /* Handle null pointer to member function conversions. */
6319 if (integer_zerop (pfn))
6321 pfn = build_c_cast (type, integer_zero_node);
6322 return build_ptrmemfunc1 (to_type,
6327 if (type_unknown_p (pfn))
6328 return instantiate_type (type, pfn, tf_warning_or_error);
6330 fn = TREE_OPERAND (pfn, 0);
6331 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
6332 /* In a template, we will have preserved the
6334 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
6335 return make_ptrmem_cst (to_type, fn);
6338 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
6341 ??? There is no consistency as to the types returned for the above
6342 values. Some code acts as if it were a sizetype and some as if it were
6343 integer_type_node. */
6346 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
6348 tree type = TREE_TYPE (cst);
6349 tree fn = PTRMEM_CST_MEMBER (cst);
6350 tree ptr_class, fn_class;
6352 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6354 /* The class that the function belongs to. */
6355 fn_class = DECL_CONTEXT (fn);
6357 /* The class that we're creating a pointer to member of. */
6358 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
6360 /* First, calculate the adjustment to the function's class. */
6361 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
6364 if (!DECL_VIRTUAL_P (fn))
6365 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
6368 /* If we're dealing with a virtual function, we have to adjust 'this'
6369 again, to point to the base which provides the vtable entry for
6370 fn; the call will do the opposite adjustment. */
6371 tree orig_class = DECL_CONTEXT (fn);
6372 tree binfo = binfo_or_else (orig_class, fn_class);
6373 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6374 *delta, BINFO_OFFSET (binfo));
6375 *delta = fold_if_not_in_template (*delta);
6377 /* We set PFN to the vtable offset at which the function can be
6378 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6379 case delta is shifted left, and then incremented). */
6380 *pfn = DECL_VINDEX (fn);
6381 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
6382 TYPE_SIZE_UNIT (vtable_entry_type));
6383 *pfn = fold_if_not_in_template (*pfn);
6385 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
6387 case ptrmemfunc_vbit_in_pfn:
6388 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6390 *pfn = fold_if_not_in_template (*pfn);
6393 case ptrmemfunc_vbit_in_delta:
6394 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6395 *delta, integer_one_node);
6396 *delta = fold_if_not_in_template (*delta);
6397 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6398 *delta, integer_one_node);
6399 *delta = fold_if_not_in_template (*delta);
6406 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6407 *pfn = fold_if_not_in_template (*pfn);
6411 /* Return an expression for PFN from the pointer-to-member function
6415 pfn_from_ptrmemfunc (tree t)
6417 if (TREE_CODE (t) == PTRMEM_CST)
6422 expand_ptrmemfunc_cst (t, &delta, &pfn);
6427 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6430 /* Return an expression for DELTA from the pointer-to-member function
6434 delta_from_ptrmemfunc (tree t)
6436 if (TREE_CODE (t) == PTRMEM_CST)
6441 expand_ptrmemfunc_cst (t, &delta, &pfn);
6446 return build_ptrmemfunc_access_expr (t, delta_identifier);
6449 /* Convert value RHS to type TYPE as preparation for an assignment to
6450 an lvalue of type TYPE. ERRTYPE is a string to use in error
6451 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6452 are doing the conversion in order to pass the PARMNUMth argument of
6456 convert_for_assignment (tree type, tree rhs,
6457 const char *errtype, tree fndecl, int parmnum,
6458 tsubst_flags_t complain)
6461 enum tree_code coder;
6463 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6464 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6465 rhs = TREE_OPERAND (rhs, 0);
6467 rhstype = TREE_TYPE (rhs);
6468 coder = TREE_CODE (rhstype);
6470 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6471 && vector_types_convertible_p (type, rhstype, true))
6472 return convert (type, rhs);
6474 if (rhs == error_mark_node || rhstype == error_mark_node)
6475 return error_mark_node;
6476 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6477 return error_mark_node;
6479 /* The RHS of an assignment cannot have void type. */
6480 if (coder == VOID_TYPE)
6482 if (complain & tf_error)
6483 error ("void value not ignored as it ought to be");
6484 return error_mark_node;
6487 /* Simplify the RHS if possible. */
6488 if (TREE_CODE (rhs) == CONST_DECL)
6489 rhs = DECL_INITIAL (rhs);
6491 if (c_dialect_objc ())
6494 tree rname = fndecl;
6496 if (!strcmp (errtype, "assignment"))
6498 else if (!strcmp (errtype, "initialization"))
6502 tree selector = objc_message_selector ();
6506 if (selector && parmno > 1)
6513 if (objc_compare_types (type, rhstype, parmno, rname))
6514 return convert (type, rhs);
6519 The expression is implicitly converted (clause _conv_) to the
6520 cv-unqualified type of the left operand.
6522 We allow bad conversions here because by the time we get to this point
6523 we are committed to doing the conversion. If we end up doing a bad
6524 conversion, convert_like will complain. */
6525 if (!can_convert_arg_bad (type, rhstype, rhs))
6527 /* When -Wno-pmf-conversions is use, we just silently allow
6528 conversions from pointers-to-members to plain pointers. If
6529 the conversion doesn't work, cp_convert will complain. */
6531 && TYPE_PTR_P (type)
6532 && TYPE_PTRMEMFUNC_P (rhstype))
6533 rhs = cp_convert (strip_top_quals (type), rhs);
6536 if (complain & tf_error)
6538 /* If the right-hand side has unknown type, then it is an
6539 overloaded function. Call instantiate_type to get error
6541 if (rhstype == unknown_type_node)
6542 instantiate_type (type, rhs, tf_warning_or_error);
6544 error ("cannot convert %qT to %qT for argument %qP to %qD",
6545 rhstype, type, parmnum, fndecl);
6547 error ("cannot convert %qT to %qT in %s", rhstype, type,
6550 return error_mark_node;
6553 if (warn_missing_format_attribute)
6555 const enum tree_code codel = TREE_CODE (type);
6556 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6558 && check_missing_format_attribute (type, rhstype)
6559 && (complain & tf_warning))
6560 warning (OPT_Wmissing_format_attribute,
6561 "%s might be a candidate for a format attribute",
6565 /* If -Wparentheses, warn about a = b = c when a has type bool and b
6567 if (warn_parentheses
6568 && type == boolean_type_node
6569 && TREE_CODE (rhs) == MODIFY_EXPR
6570 && !TREE_NO_WARNING (rhs)
6571 && TREE_TYPE (rhs) != boolean_type_node
6572 && (complain & tf_warning))
6574 warning (OPT_Wparentheses,
6575 "suggest parentheses around assignment used as truth value");
6576 TREE_NO_WARNING (rhs) = 1;
6579 return perform_implicit_conversion (strip_top_quals (type), rhs, complain);
6582 /* Convert RHS to be of type TYPE.
6583 If EXP is nonzero, it is the target of the initialization.
6584 ERRTYPE is a string to use in error messages.
6586 Two major differences between the behavior of
6587 `convert_for_assignment' and `convert_for_initialization'
6588 are that references are bashed in the former, while
6589 copied in the latter, and aggregates are assigned in
6590 the former (operator=) while initialized in the
6593 If using constructor make sure no conversion operator exists, if one does
6594 exist, an ambiguity exists.
6596 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6599 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6600 const char *errtype, tree fndecl, int parmnum,
6601 tsubst_flags_t complain)
6603 enum tree_code codel = TREE_CODE (type);
6605 enum tree_code coder;
6607 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6608 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6609 if (TREE_CODE (rhs) == NOP_EXPR
6610 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6611 && codel != REFERENCE_TYPE)
6612 rhs = TREE_OPERAND (rhs, 0);
6614 if (type == error_mark_node
6615 || rhs == error_mark_node
6616 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6617 return error_mark_node;
6619 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6620 && TREE_CODE (type) != ARRAY_TYPE
6621 && (TREE_CODE (type) != REFERENCE_TYPE
6622 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6623 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6624 && (TREE_CODE (type) != REFERENCE_TYPE
6625 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6626 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6627 rhs = decay_conversion (rhs);
6629 rhstype = TREE_TYPE (rhs);
6630 coder = TREE_CODE (rhstype);
6632 if (coder == ERROR_MARK)
6633 return error_mark_node;
6635 /* We accept references to incomplete types, so we can
6636 return here before checking if RHS is of complete type. */
6638 if (codel == REFERENCE_TYPE)
6640 /* This should eventually happen in convert_arguments. */
6641 int savew = 0, savee = 0;
6644 savew = warningcount, savee = errorcount;
6645 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6649 if (warningcount > savew)
6650 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6651 else if (errorcount > savee)
6652 error ("in passing argument %P of %q+D", parmnum, fndecl);
6658 exp = require_complete_type (exp);
6659 if (exp == error_mark_node)
6660 return error_mark_node;
6662 rhstype = non_reference (rhstype);
6664 type = complete_type (type);
6666 if (MAYBE_CLASS_TYPE_P (type))
6667 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6669 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum,
6673 /* If RETVAL is the address of, or a reference to, a local variable or
6674 temporary give an appropriate warning. */
6677 maybe_warn_about_returning_address_of_local (tree retval)
6679 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6680 tree whats_returned = retval;
6684 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6685 whats_returned = TREE_OPERAND (whats_returned, 1);
6686 else if (CONVERT_EXPR_P (whats_returned)
6687 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR)
6688 whats_returned = TREE_OPERAND (whats_returned, 0);
6693 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6695 whats_returned = TREE_OPERAND (whats_returned, 0);
6697 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6699 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6700 || TREE_CODE (whats_returned) == TARGET_EXPR)
6702 warning (0, "returning reference to temporary");
6705 if (TREE_CODE (whats_returned) == VAR_DECL
6706 && DECL_NAME (whats_returned)
6707 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6709 warning (0, "reference to non-lvalue returned");
6714 while (TREE_CODE (whats_returned) == COMPONENT_REF
6715 || TREE_CODE (whats_returned) == ARRAY_REF)
6716 whats_returned = TREE_OPERAND (whats_returned, 0);
6718 if (DECL_P (whats_returned)
6719 && DECL_NAME (whats_returned)
6720 && DECL_FUNCTION_SCOPE_P (whats_returned)
6721 && !(TREE_STATIC (whats_returned)
6722 || TREE_PUBLIC (whats_returned)))
6724 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6725 warning (0, "reference to local variable %q+D returned",
6728 warning (0, "address of local variable %q+D returned",
6734 /* Check that returning RETVAL from the current function is valid.
6735 Return an expression explicitly showing all conversions required to
6736 change RETVAL into the function return type, and to assign it to
6737 the DECL_RESULT for the function. Set *NO_WARNING to true if
6738 code reaches end of non-void function warning shouldn't be issued
6739 on this RETURN_EXPR. */
6742 check_return_expr (tree retval, bool *no_warning)
6745 /* The type actually returned by the function, after any
6748 int fn_returns_value_p;
6749 bool named_return_value_okay_p;
6751 *no_warning = false;
6753 /* A `volatile' function is one that isn't supposed to return, ever.
6754 (This is a G++ extension, used to get better code for functions
6755 that call the `volatile' function.) */
6756 if (TREE_THIS_VOLATILE (current_function_decl))
6757 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6759 /* Check for various simple errors. */
6760 if (DECL_DESTRUCTOR_P (current_function_decl))
6763 error ("returning a value from a destructor");
6766 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6768 if (in_function_try_handler)
6769 /* If a return statement appears in a handler of the
6770 function-try-block of a constructor, the program is ill-formed. */
6771 error ("cannot return from a handler of a function-try-block of a constructor");
6773 /* You can't return a value from a constructor. */
6774 error ("returning a value from a constructor");
6778 if (processing_template_decl)
6780 current_function_returns_value = 1;
6781 if (check_for_bare_parameter_packs (retval))
6782 retval = error_mark_node;
6786 /* When no explicit return-value is given in a function with a named
6787 return value, the named return value is used. */
6788 result = DECL_RESULT (current_function_decl);
6789 valtype = TREE_TYPE (result);
6790 gcc_assert (valtype != NULL_TREE);
6791 fn_returns_value_p = !VOID_TYPE_P (valtype);
6792 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6795 /* Check for a return statement with no return value in a function
6796 that's supposed to return a value. */
6797 if (!retval && fn_returns_value_p)
6799 permerror (input_location, "return-statement with no value, in function returning %qT",
6801 /* Clear this, so finish_function won't say that we reach the
6802 end of a non-void function (which we don't, we gave a
6804 current_function_returns_null = 0;
6805 /* And signal caller that TREE_NO_WARNING should be set on the
6806 RETURN_EXPR to avoid control reaches end of non-void function
6807 warnings in tree-cfg.c. */
6810 /* Check for a return statement with a value in a function that
6811 isn't supposed to return a value. */
6812 else if (retval && !fn_returns_value_p)
6814 if (VOID_TYPE_P (TREE_TYPE (retval)))
6815 /* You can return a `void' value from a function of `void'
6816 type. In that case, we have to evaluate the expression for
6817 its side-effects. */
6818 finish_expr_stmt (retval);
6820 permerror (input_location, "return-statement with a value, in function "
6821 "returning 'void'");
6822 current_function_returns_null = 1;
6824 /* There's really no value to return, after all. */
6828 /* Remember that this function can sometimes return without a
6830 current_function_returns_null = 1;
6832 /* Remember that this function did return a value. */
6833 current_function_returns_value = 1;
6835 /* Check for erroneous operands -- but after giving ourselves a
6836 chance to provide an error about returning a value from a void
6838 if (error_operand_p (retval))
6840 current_function_return_value = error_mark_node;
6841 return error_mark_node;
6844 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
6845 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
6846 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
6847 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
6849 && retval && null_ptr_cst_p (retval))
6850 warning (0, "%<operator new%> must not return NULL unless it is "
6851 "declared %<throw()%> (or -fcheck-new is in effect)");
6853 /* Effective C++ rule 15. See also start_function. */
6855 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
6859 /* The function return type must be a reference to the current
6861 if (TREE_CODE (valtype) == REFERENCE_TYPE
6862 && same_type_ignoring_top_level_qualifiers_p
6863 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
6865 /* Returning '*this' is obviously OK. */
6866 if (retval == current_class_ref)
6868 /* If we are calling a function whose return type is the same of
6869 the current class reference, it is ok. */
6870 else if (TREE_CODE (retval) == INDIRECT_REF
6871 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
6876 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
6879 /* The fabled Named Return Value optimization, as per [class.copy]/15:
6881 [...] For a function with a class return type, if the expression
6882 in the return statement is the name of a local object, and the cv-
6883 unqualified type of the local object is the same as the function
6884 return type, an implementation is permitted to omit creating the tem-
6885 porary object to hold the function return value [...]
6887 So, if this is a value-returning function that always returns the same
6888 local variable, remember it.
6890 It might be nice to be more flexible, and choose the first suitable
6891 variable even if the function sometimes returns something else, but
6892 then we run the risk of clobbering the variable we chose if the other
6893 returned expression uses the chosen variable somehow. And people expect
6894 this restriction, anyway. (jason 2000-11-19)
6896 See finish_function and finalize_nrv for the rest of this optimization. */
6898 named_return_value_okay_p =
6899 (retval != NULL_TREE
6900 /* Must be a local, automatic variable. */
6901 && TREE_CODE (retval) == VAR_DECL
6902 && DECL_CONTEXT (retval) == current_function_decl
6903 && ! TREE_STATIC (retval)
6904 && ! DECL_ANON_UNION_VAR_P (retval)
6905 && (DECL_ALIGN (retval)
6906 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6907 /* The cv-unqualified type of the returned value must be the
6908 same as the cv-unqualified return type of the
6910 && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))),
6912 (TREE_TYPE (TREE_TYPE (current_function_decl)))))
6913 /* And the returned value must be non-volatile. */
6914 && ! TYPE_VOLATILE (TREE_TYPE (retval)));
6916 if (fn_returns_value_p && flag_elide_constructors)
6918 if (named_return_value_okay_p
6919 && (current_function_return_value == NULL_TREE
6920 || current_function_return_value == retval))
6921 current_function_return_value = retval;
6923 current_function_return_value = error_mark_node;
6926 /* We don't need to do any conversions when there's nothing being
6931 /* Do any required conversions. */
6932 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6933 /* No conversions are required. */
6937 /* The type the function is declared to return. */
6938 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6939 int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
6941 /* The functype's return type will have been set to void, if it
6942 was an incomplete type. Just treat this as 'return;' */
6943 if (VOID_TYPE_P (functype))
6944 return error_mark_node;
6946 /* Under C++0x [12.8/16 class.copy], a returned lvalue is sometimes
6947 treated as an rvalue for the purposes of overload resolution to
6948 favor move constructors over copy constructors. */
6949 if ((cxx_dialect != cxx98)
6950 && named_return_value_okay_p
6951 /* The variable must not have the `volatile' qualifier. */
6952 && !(cp_type_quals (TREE_TYPE (retval)) & TYPE_QUAL_VOLATILE)
6953 /* The return type must be a class type. */
6954 && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
6955 flags = flags | LOOKUP_PREFER_RVALUE;
6957 /* First convert the value to the function's return type, then
6958 to the type of return value's location to handle the
6959 case that functype is smaller than the valtype. */
6960 retval = convert_for_initialization
6961 (NULL_TREE, functype, retval, flags, "return", NULL_TREE, 0,
6962 tf_warning_or_error);
6963 retval = convert (valtype, retval);
6965 /* If the conversion failed, treat this just like `return;'. */
6966 if (retval == error_mark_node)
6968 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6969 else if (! cfun->returns_struct
6970 && TREE_CODE (retval) == TARGET_EXPR
6971 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6972 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6973 TREE_OPERAND (retval, 0));
6975 maybe_warn_about_returning_address_of_local (retval);
6978 /* Actually copy the value returned into the appropriate location. */
6979 if (retval && retval != result)
6980 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
6986 /* Returns nonzero if the pointer-type FROM can be converted to the
6987 pointer-type TO via a qualification conversion. If CONSTP is -1,
6988 then we return nonzero if the pointers are similar, and the
6989 cv-qualification signature of FROM is a proper subset of that of TO.
6991 If CONSTP is positive, then all outer pointers have been
6995 comp_ptr_ttypes_real (tree to, tree from, int constp)
6997 bool to_more_cv_qualified = false;
6998 bool is_opaque_pointer = false;
7000 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7002 if (TREE_CODE (to) != TREE_CODE (from))
7005 if (TREE_CODE (from) == OFFSET_TYPE
7006 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
7007 TYPE_OFFSET_BASETYPE (to)))
7010 /* Const and volatile mean something different for function types,
7011 so the usual checks are not appropriate. */
7012 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
7014 /* In Objective-C++, some types may have been 'volatilized' by
7015 the compiler for EH; when comparing them here, the volatile
7016 qualification must be ignored. */
7017 bool objc_quals_match = objc_type_quals_match (to, from);
7019 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
7022 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
7026 to_more_cv_qualified = true;
7030 constp &= TYPE_READONLY (to);
7033 if (TREE_CODE (to) == VECTOR_TYPE)
7034 is_opaque_pointer = vector_targets_convertible_p (to, from);
7036 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
7037 return ((constp >= 0 || to_more_cv_qualified)
7038 && (is_opaque_pointer
7039 || same_type_ignoring_top_level_qualifiers_p (to, from)));
7043 /* When comparing, say, char ** to char const **, this function takes
7044 the 'char *' and 'char const *'. Do not pass non-pointer/reference
7045 types to this function. */
7048 comp_ptr_ttypes (tree to, tree from)
7050 return comp_ptr_ttypes_real (to, from, 1);
7053 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
7054 type or inheritance-related types, regardless of cv-quals. */
7057 ptr_reasonably_similar (const_tree to, const_tree from)
7059 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7061 /* Any target type is similar enough to void. */
7062 if (TREE_CODE (to) == VOID_TYPE
7063 || TREE_CODE (from) == VOID_TYPE)
7066 if (TREE_CODE (to) != TREE_CODE (from))
7069 if (TREE_CODE (from) == OFFSET_TYPE
7070 && comptypes (TYPE_OFFSET_BASETYPE (to),
7071 TYPE_OFFSET_BASETYPE (from),
7072 COMPARE_BASE | COMPARE_DERIVED))
7075 if (TREE_CODE (to) == VECTOR_TYPE
7076 && vector_types_convertible_p (to, from, false))
7079 if (TREE_CODE (to) == INTEGER_TYPE
7080 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
7083 if (TREE_CODE (to) == FUNCTION_TYPE)
7086 if (TREE_CODE (to) != POINTER_TYPE)
7088 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
7089 COMPARE_BASE | COMPARE_DERIVED);
7093 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
7094 pointer-to-member types) are the same, ignoring cv-qualification at
7098 comp_ptr_ttypes_const (tree to, tree from)
7100 bool is_opaque_pointer = false;
7102 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7104 if (TREE_CODE (to) != TREE_CODE (from))
7107 if (TREE_CODE (from) == OFFSET_TYPE
7108 && same_type_p (TYPE_OFFSET_BASETYPE (from),
7109 TYPE_OFFSET_BASETYPE (to)))
7112 if (TREE_CODE (to) == VECTOR_TYPE)
7113 is_opaque_pointer = vector_targets_convertible_p (to, from);
7115 if (TREE_CODE (to) != POINTER_TYPE)
7116 return (is_opaque_pointer
7117 || same_type_ignoring_top_level_qualifiers_p (to, from));
7121 /* Returns the type qualifiers for this type, including the qualifiers on the
7122 elements for an array type. */
7125 cp_type_quals (const_tree type)
7127 /* This CONST_CAST is okay because strip_array_types returns its
7128 argument unmodified and we assign it to a const_tree. */
7129 type = strip_array_types (CONST_CAST_TREE(type));
7130 if (type == error_mark_node)
7131 return TYPE_UNQUALIFIED;
7132 return TYPE_QUALS (type);
7135 /* Returns nonzero if the TYPE is const from a C++ perspective: look inside
7139 cp_type_readonly (const_tree type)
7141 /* This CONST_CAST is okay because strip_array_types returns its
7142 argument unmodified and we assign it to a const_tree. */
7143 type = strip_array_types (CONST_CAST_TREE(type));
7144 return TYPE_READONLY (type);
7147 /* Returns nonzero if the TYPE contains a mutable member. */
7150 cp_has_mutable_p (const_tree type)
7152 /* This CONST_CAST is okay because strip_array_types returns its
7153 argument unmodified and we assign it to a const_tree. */
7154 type = strip_array_types (CONST_CAST_TREE(type));
7156 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
7159 /* Set TREE_READONLY and TREE_VOLATILE on DECL as indicated by the
7160 TYPE_QUALS. For a VAR_DECL, this may be an optimistic
7161 approximation. In particular, consider:
7164 struct S { int i; };
7165 const S s = { f(); }
7167 Here, we will make "s" as TREE_READONLY (because it is declared
7168 "const") -- only to reverse ourselves upon seeing that the
7169 initializer is non-constant. */
7172 cp_apply_type_quals_to_decl (int type_quals, tree decl)
7174 tree type = TREE_TYPE (decl);
7176 if (type == error_mark_node)
7179 if (TREE_CODE (type) == FUNCTION_TYPE
7180 && type_quals != TYPE_UNQUALIFIED)
7182 /* This was an error in C++98 (cv-qualifiers cannot be added to
7183 a function type), but DR 295 makes the code well-formed by
7184 dropping the extra qualifiers. */
7187 tree bad_type = build_qualified_type (type, type_quals);
7188 pedwarn (input_location, OPT_pedantic,
7189 "ignoring %qV qualifiers added to function type %qT",
7193 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
7197 /* Avoid setting TREE_READONLY incorrectly. */
7198 if (/* If the object has a constructor, the constructor may modify
7200 TYPE_NEEDS_CONSTRUCTING (type)
7201 /* If the type isn't complete, we don't know yet if it will need
7203 || !COMPLETE_TYPE_P (type)
7204 /* If the type has a mutable component, that component might be
7206 || TYPE_HAS_MUTABLE_P (type))
7207 type_quals &= ~TYPE_QUAL_CONST;
7209 c_apply_type_quals_to_decl (type_quals, decl);
7212 /* Subroutine of casts_away_constness. Make T1 and T2 point at
7213 exemplar types such that casting T1 to T2 is casting away constness
7214 if and only if there is no implicit conversion from T1 to T2. */
7217 casts_away_constness_r (tree *t1, tree *t2)
7222 /* [expr.const.cast]
7224 For multi-level pointer to members and multi-level mixed pointers
7225 and pointers to members (conv.qual), the "member" aspect of a
7226 pointer to member level is ignored when determining if a const
7227 cv-qualifier has been cast away. */
7228 /* [expr.const.cast]
7230 For two pointer types:
7232 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
7233 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
7236 casting from X1 to X2 casts away constness if, for a non-pointer
7237 type T there does not exist an implicit conversion (clause
7240 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
7244 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
7245 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
7246 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
7248 *t1 = cp_build_qualified_type (void_type_node,
7249 cp_type_quals (*t1));
7250 *t2 = cp_build_qualified_type (void_type_node,
7251 cp_type_quals (*t2));
7255 quals1 = cp_type_quals (*t1);
7256 quals2 = cp_type_quals (*t2);
7258 if (TYPE_PTRMEM_P (*t1))
7259 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
7261 *t1 = TREE_TYPE (*t1);
7262 if (TYPE_PTRMEM_P (*t2))
7263 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
7265 *t2 = TREE_TYPE (*t2);
7267 casts_away_constness_r (t1, t2);
7268 *t1 = build_pointer_type (*t1);
7269 *t2 = build_pointer_type (*t2);
7270 *t1 = cp_build_qualified_type (*t1, quals1);
7271 *t2 = cp_build_qualified_type (*t2, quals2);
7274 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
7278 casts_away_constness (tree t1, tree t2)
7280 if (TREE_CODE (t2) == REFERENCE_TYPE)
7282 /* [expr.const.cast]
7284 Casting from an lvalue of type T1 to an lvalue of type T2
7285 using a reference cast casts away constness if a cast from an
7286 rvalue of type "pointer to T1" to the type "pointer to T2"
7287 casts away constness. */
7288 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
7289 return casts_away_constness (build_pointer_type (t1),
7290 build_pointer_type (TREE_TYPE (t2)));
7293 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
7294 /* [expr.const.cast]
7296 Casting from an rvalue of type "pointer to data member of X
7297 of type T1" to the type "pointer to data member of Y of type
7298 T2" casts away constness if a cast from an rvalue of type
7299 "pointer to T1" to the type "pointer to T2" casts away
7301 return casts_away_constness
7302 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
7303 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
7305 /* Casting away constness is only something that makes sense for
7306 pointer or reference types. */
7307 if (TREE_CODE (t1) != POINTER_TYPE
7308 || TREE_CODE (t2) != POINTER_TYPE)
7311 /* Top-level qualifiers don't matter. */
7312 t1 = TYPE_MAIN_VARIANT (t1);
7313 t2 = TYPE_MAIN_VARIANT (t2);
7314 casts_away_constness_r (&t1, &t2);
7315 if (!can_convert (t2, t1))
7321 /* If T is a REFERENCE_TYPE return the type to which T refers.
7322 Otherwise, return T itself. */
7325 non_reference (tree t)
7327 if (TREE_CODE (t) == REFERENCE_TYPE)
7333 /* Return nonzero if REF is an lvalue valid for this language;
7334 otherwise, print an error message and return zero. USE says
7335 how the lvalue is being used and so selects the error message. */
7338 lvalue_or_else (const_tree ref, enum lvalue_use use, tsubst_flags_t complain)
7340 int win = lvalue_p (ref);
7342 if (!win && (complain & tf_error))