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 (t2))
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);
2793 /* If the object is not dynamic the access invokes undefined
2794 behavior. As it is not executed in this case silence the
2795 spurious warnings it may provoke. */
2796 TREE_NO_WARNING (vtbl) = 1;
2798 /* Finally, extract the function pointer from the vtable. */
2799 e2 = fold_build2 (POINTER_PLUS_EXPR, TREE_TYPE (vtbl), vtbl,
2800 fold_convert (sizetype, idx));
2801 e2 = cp_build_indirect_ref (e2, NULL, tf_warning_or_error);
2802 TREE_CONSTANT (e2) = 1;
2804 /* When using function descriptors, the address of the
2805 vtable entry is treated as a function pointer. */
2806 if (TARGET_VTABLE_USES_DESCRIPTORS)
2807 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2808 cp_build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1,
2809 tf_warning_or_error));
2811 e2 = fold_convert (TREE_TYPE (e3), e2);
2812 e1 = build_conditional_expr (e1, e2, e3, tf_warning_or_error);
2814 /* Make sure this doesn't get evaluated first inside one of the
2815 branches of the COND_EXPR. */
2816 if (instance_save_expr)
2817 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2818 instance_save_expr, e1);
2825 /* Used by the C-common bits. */
2827 build_function_call (tree function, tree params)
2829 return cp_build_function_call (function, params, tf_warning_or_error);
2833 cp_build_function_call (tree function, tree params, tsubst_flags_t complain)
2835 tree fntype, fndecl;
2836 tree name = NULL_TREE;
2838 tree original = function;
2839 int nargs, parm_types_len;
2843 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2844 expressions, like those used for ObjC messenger dispatches. */
2845 function = objc_rewrite_function_call (function, params);
2847 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2848 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2849 if (TREE_CODE (function) == NOP_EXPR
2850 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2851 function = TREE_OPERAND (function, 0);
2853 if (TREE_CODE (function) == FUNCTION_DECL)
2855 name = DECL_NAME (function);
2857 mark_used (function);
2860 /* Convert anything with function type to a pointer-to-function. */
2861 if (DECL_MAIN_P (function) && (complain & tf_error))
2862 pedwarn (input_location, OPT_pedantic,
2863 "ISO C++ forbids calling %<::main%> from within program");
2865 function = build_addr_func (function);
2871 function = build_addr_func (function);
2874 if (function == error_mark_node)
2875 return error_mark_node;
2877 fntype = TREE_TYPE (function);
2879 if (TYPE_PTRMEMFUNC_P (fntype))
2881 if (complain & tf_error)
2882 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2883 "function in %<%E (...)%>, e.g. %<(... ->* %E) (...)%>",
2884 original, original);
2885 return error_mark_node;
2888 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2889 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2891 if (!((TREE_CODE (fntype) == POINTER_TYPE
2892 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2894 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2896 if (complain & tf_error)
2897 error ("%qE cannot be used as a function", original);
2898 return error_mark_node;
2901 /* fntype now gets the type of function pointed to. */
2902 fntype = TREE_TYPE (fntype);
2903 parm_types = TYPE_ARG_TYPES (fntype);
2905 /* Allocate storage for converted arguments. */
2906 parm_types_len = list_length (parm_types);
2907 nargs = list_length (params);
2908 if (parm_types_len > nargs)
2909 nargs = parm_types_len;
2910 argarray = (tree *) alloca (nargs * sizeof (tree));
2912 /* Convert the parameters to the types declared in the
2913 function prototype, or apply default promotions. */
2914 nargs = convert_arguments (nargs, argarray, parm_types,
2915 params, fndecl, LOOKUP_NORMAL,
2918 return error_mark_node;
2920 /* Check for errors in format strings and inappropriately
2922 check_function_arguments (TYPE_ATTRIBUTES (fntype), nargs, argarray,
2925 return build_cxx_call (function, nargs, argarray);
2928 /* Convert the actual parameter expressions in the list VALUES
2929 to the types in the list TYPELIST.
2930 If parmdecls is exhausted, or when an element has NULL as its type,
2931 perform the default conversions.
2933 Store the converted arguments in ARGARRAY. NARGS is the size of this array.
2935 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2937 This is also where warnings about wrong number of args are generated.
2939 Returns the actual number of arguments processed (which might be less
2940 than NARGS), or -1 on error.
2942 VALUES is a chain of TREE_LIST nodes with the elements of the list
2943 in the TREE_VALUE slots of those nodes.
2945 In C++, unspecified trailing parameters can be filled in with their
2946 default arguments, if such were specified. Do so here. */
2949 convert_arguments (int nargs, tree *argarray,
2950 tree typelist, tree values, tree fndecl, int flags,
2951 tsubst_flags_t complain)
2953 tree typetail, valtail;
2954 const char *called_thing = 0;
2957 /* Argument passing is always copy-initialization. */
2958 flags |= LOOKUP_ONLYCONVERTING;
2962 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2964 if (DECL_NAME (fndecl) == NULL_TREE
2965 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2966 called_thing = "constructor";
2968 called_thing = "member function";
2971 called_thing = "function";
2974 for (valtail = values, typetail = typelist;
2976 valtail = TREE_CHAIN (valtail), i++)
2978 tree type = typetail ? TREE_VALUE (typetail) : 0;
2979 tree val = TREE_VALUE (valtail);
2981 if (val == error_mark_node || type == error_mark_node)
2984 if (type == void_type_node)
2986 if (complain & tf_error)
2990 error ("too many arguments to %s %q+#D",
2991 called_thing, fndecl);
2992 error ("at this point in file");
2995 error ("too many arguments to function");
3002 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
3003 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
3004 if (TREE_CODE (val) == NOP_EXPR
3005 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
3006 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
3007 val = TREE_OPERAND (val, 0);
3009 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
3011 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
3012 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
3013 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
3014 val = decay_conversion (val);
3017 if (val == error_mark_node)
3022 /* Formal parm type is specified by a function prototype. */
3025 if (!COMPLETE_TYPE_P (complete_type (type)))
3027 if (complain & tf_error)
3030 error ("parameter %P of %qD has incomplete type %qT",
3033 error ("parameter %P has incomplete type %qT", i, type);
3035 parmval = error_mark_node;
3039 parmval = convert_for_initialization
3040 (NULL_TREE, type, val, flags,
3041 "argument passing", fndecl, i, complain);
3042 parmval = convert_for_arg_passing (type, parmval);
3045 if (parmval == error_mark_node)
3048 argarray[i] = parmval;
3052 if (fndecl && DECL_BUILT_IN (fndecl)
3053 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
3054 /* Don't do ellipsis conversion for __built_in_constant_p
3055 as this will result in spurious warnings for non-POD
3057 val = require_complete_type (val);
3059 val = convert_arg_to_ellipsis (val);
3065 typetail = TREE_CHAIN (typetail);
3068 if (typetail != 0 && typetail != void_list_node)
3070 /* See if there are default arguments that can be used. Because
3071 we hold default arguments in the FUNCTION_TYPE (which is so
3072 wrong), we can see default parameters here from deduced
3073 contexts (and via typeof) for indirect function calls.
3074 Fortunately we know whether we have a function decl to
3075 provide default arguments in a language conformant
3077 if (fndecl && TREE_PURPOSE (typetail)
3078 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
3080 for (; typetail != void_list_node; ++i)
3083 = convert_default_arg (TREE_VALUE (typetail),
3084 TREE_PURPOSE (typetail),
3087 if (parmval == error_mark_node)
3090 argarray[i] = parmval;
3091 typetail = TREE_CHAIN (typetail);
3092 /* ends with `...'. */
3093 if (typetail == NULL_TREE)
3099 if (complain & tf_error)
3103 error ("too few arguments to %s %q+#D",
3104 called_thing, fndecl);
3105 error ("at this point in file");
3108 error ("too few arguments to function");
3114 gcc_assert (i <= nargs);
3118 /* Build a binary-operation expression, after performing default
3119 conversions on the operands. CODE is the kind of expression to
3120 build. ARG1 and ARG2 are the arguments. ARG1_CODE and ARG2_CODE
3121 are the tree codes which correspond to ARG1 and ARG2 when issuing
3122 warnings about possibly misplaced parentheses. They may differ
3123 from the TREE_CODE of ARG1 and ARG2 if the parser has done constant
3124 folding (e.g., if the parser sees "a | 1 + 1", it may call this
3125 routine with ARG2 being an INTEGER_CST and ARG2_CODE == PLUS_EXPR).
3126 To avoid issuing any parentheses warnings, pass ARG1_CODE and/or
3127 ARG2_CODE as ERROR_MARK. */
3130 build_x_binary_op (enum tree_code code, tree arg1, enum tree_code arg1_code,
3131 tree arg2, enum tree_code arg2_code, bool *overloaded_p,
3132 tsubst_flags_t complain)
3141 if (processing_template_decl)
3143 if (type_dependent_expression_p (arg1)
3144 || type_dependent_expression_p (arg2))
3145 return build_min_nt (code, arg1, arg2);
3146 arg1 = build_non_dependent_expr (arg1);
3147 arg2 = build_non_dependent_expr (arg2);
3150 if (code == DOTSTAR_EXPR)
3151 expr = build_m_component_ref (arg1, arg2);
3153 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
3154 overloaded_p, complain);
3156 /* Check for cases such as x+y<<z which users are likely to
3157 misinterpret. But don't warn about obj << x + y, since that is a
3158 common idiom for I/O. */
3159 if (warn_parentheses
3160 && !processing_template_decl
3161 && !error_operand_p (arg1)
3162 && !error_operand_p (arg2)
3163 && (code != LSHIFT_EXPR
3164 || !CLASS_TYPE_P (TREE_TYPE (arg1))))
3165 warn_about_parentheses (code, arg1_code, orig_arg1, arg2_code, orig_arg2);
3167 if (processing_template_decl && expr != error_mark_node)
3168 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
3173 /* For the c-common bits. */
3175 build_binary_op (location_t location, enum tree_code code, tree op0, tree op1,
3176 int convert_p ATTRIBUTE_UNUSED)
3178 return cp_build_binary_op (location, code, op0, op1, tf_warning_or_error);
3182 /* Build a binary-operation expression without default conversions.
3183 CODE is the kind of expression to build.
3184 LOCATION is the location_t of the operator in the source code.
3185 This function differs from `build' in several ways:
3186 the data type of the result is computed and recorded in it,
3187 warnings are generated if arg data types are invalid,
3188 special handling for addition and subtraction of pointers is known,
3189 and some optimization is done (operations on narrow ints
3190 are done in the narrower type when that gives the same result).
3191 Constant folding is also done before the result is returned.
3193 Note that the operands will never have enumeral types
3194 because either they have just had the default conversions performed
3195 or they have both just been converted to some other type in which
3196 the arithmetic is to be done.
3198 C++: must do special pointer arithmetic when implementing
3199 multiple inheritance, and deal with pointer to member functions. */
3202 cp_build_binary_op (location_t location,
3203 enum tree_code code, tree orig_op0, tree orig_op1,
3204 tsubst_flags_t complain)
3207 enum tree_code code0, code1;
3209 const char *invalid_op_diag;
3211 /* Expression code to give to the expression when it is built.
3212 Normally this is CODE, which is what the caller asked for,
3213 but in some special cases we change it. */
3214 enum tree_code resultcode = code;
3216 /* Data type in which the computation is to be performed.
3217 In the simplest cases this is the common type of the arguments. */
3218 tree result_type = NULL;
3220 /* Nonzero means operands have already been type-converted
3221 in whatever way is necessary.
3222 Zero means they need to be converted to RESULT_TYPE. */
3225 /* Nonzero means create the expression with this type, rather than
3227 tree build_type = 0;
3229 /* Nonzero means after finally constructing the expression
3230 convert it to this type. */
3231 tree final_type = 0;
3235 /* Nonzero if this is an operation like MIN or MAX which can
3236 safely be computed in short if both args are promoted shorts.
3237 Also implies COMMON.
3238 -1 indicates a bitwise operation; this makes a difference
3239 in the exact conditions for when it is safe to do the operation
3240 in a narrower mode. */
3243 /* Nonzero if this is a comparison operation;
3244 if both args are promoted shorts, compare the original shorts.
3245 Also implies COMMON. */
3246 int short_compare = 0;
3248 /* Nonzero means set RESULT_TYPE to the common type of the args. */
3251 /* True if both operands have arithmetic type. */
3252 bool arithmetic_types_p;
3254 /* Apply default conversions. */
3258 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
3259 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
3260 || code == TRUTH_XOR_EXPR)
3262 if (!really_overloaded_fn (op0))
3263 op0 = decay_conversion (op0);
3264 if (!really_overloaded_fn (op1))
3265 op1 = decay_conversion (op1);
3269 if (!really_overloaded_fn (op0))
3270 op0 = default_conversion (op0);
3271 if (!really_overloaded_fn (op1))
3272 op1 = default_conversion (op1);
3275 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3276 STRIP_TYPE_NOPS (op0);
3277 STRIP_TYPE_NOPS (op1);
3279 /* DTRT if one side is an overloaded function, but complain about it. */
3280 if (type_unknown_p (op0))
3282 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3283 if (t != error_mark_node)
3285 if (complain & tf_error)
3286 permerror (input_location, "assuming cast to type %qT from overloaded function",
3291 if (type_unknown_p (op1))
3293 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3294 if (t != error_mark_node)
3296 if (complain & tf_error)
3297 permerror (input_location, "assuming cast to type %qT from overloaded function",
3303 type0 = TREE_TYPE (op0);
3304 type1 = TREE_TYPE (op1);
3306 /* The expression codes of the data types of the arguments tell us
3307 whether the arguments are integers, floating, pointers, etc. */
3308 code0 = TREE_CODE (type0);
3309 code1 = TREE_CODE (type1);
3311 /* If an error was already reported for one of the arguments,
3312 avoid reporting another error. */
3314 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3315 return error_mark_node;
3317 if ((invalid_op_diag
3318 = targetm.invalid_binary_op (code, type0, type1)))
3320 error (invalid_op_diag);
3321 return error_mark_node;
3327 /* Subtraction of two similar pointers.
3328 We must subtract them as integers, then divide by object size. */
3329 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3330 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3332 return pointer_diff (op0, op1, common_pointer_type (type0, type1));
3333 /* In all other cases except pointer - int, the usual arithmetic
3335 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
3340 /* The pointer - int case is just like pointer + int; fall
3343 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
3344 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
3348 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
3349 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
3350 if (processing_template_decl)
3352 result_type = TREE_TYPE (ptr_operand);
3355 return cp_pointer_int_sum (code,
3366 case TRUNC_DIV_EXPR:
3368 case FLOOR_DIV_EXPR:
3369 case ROUND_DIV_EXPR:
3370 case EXACT_DIV_EXPR:
3371 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3372 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3373 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3374 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3376 enum tree_code tcode0 = code0, tcode1 = code1;
3378 warn_for_div_by_zero (location, op1);
3380 if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE)
3381 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3382 if (tcode1 == COMPLEX_TYPE || tcode1 == VECTOR_TYPE)
3383 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3385 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
3386 resultcode = RDIV_EXPR;
3388 /* When dividing two signed integers, we have to promote to int.
3389 unless we divide by a constant != -1. Note that default
3390 conversion will have been performed on the operands at this
3391 point, so we have to dig out the original type to find out if
3393 shorten = ((TREE_CODE (op0) == NOP_EXPR
3394 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3395 || (TREE_CODE (op1) == INTEGER_CST
3396 && ! integer_all_onesp (op1)));
3405 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3406 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE
3407 && !VECTOR_FLOAT_TYPE_P (type0)
3408 && !VECTOR_FLOAT_TYPE_P (type1)))
3412 case TRUNC_MOD_EXPR:
3413 case FLOOR_MOD_EXPR:
3414 warn_for_div_by_zero (location, op1);
3416 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3418 /* Although it would be tempting to shorten always here, that loses
3419 on some targets, since the modulo instruction is undefined if the
3420 quotient can't be represented in the computation mode. We shorten
3421 only if unsigned or if dividing by something we know != -1. */
3422 shorten = ((TREE_CODE (op0) == NOP_EXPR
3423 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3424 || (TREE_CODE (op1) == INTEGER_CST
3425 && ! integer_all_onesp (op1)));
3430 case TRUTH_ANDIF_EXPR:
3431 case TRUTH_ORIF_EXPR:
3432 case TRUTH_AND_EXPR:
3434 result_type = boolean_type_node;
3437 /* Shift operations: result has same type as first operand;
3438 always convert second operand to int.
3439 Also set SHORT_SHIFT if shifting rightward. */
3442 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3444 result_type = type0;
3445 if (TREE_CODE (op1) == INTEGER_CST)
3447 if (tree_int_cst_lt (op1, integer_zero_node))
3449 if (complain & tf_warning)
3450 warning (0, "right shift count is negative");
3454 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0
3455 && (complain & tf_warning))
3456 warning (0, "right shift count >= width of type");
3459 /* Convert the shift-count to an integer, regardless of
3460 size of value being shifted. */
3461 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3462 op1 = cp_convert (integer_type_node, op1);
3463 /* Avoid converting op1 to result_type later. */
3469 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3471 result_type = type0;
3472 if (TREE_CODE (op1) == INTEGER_CST)
3474 if (tree_int_cst_lt (op1, integer_zero_node))
3476 if (complain & tf_warning)
3477 warning (0, "left shift count is negative");
3479 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3481 if (complain & tf_warning)
3482 warning (0, "left shift count >= width of type");
3485 /* Convert the shift-count to an integer, regardless of
3486 size of value being shifted. */
3487 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3488 op1 = cp_convert (integer_type_node, op1);
3489 /* Avoid converting op1 to result_type later. */
3496 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3498 result_type = type0;
3499 if (TREE_CODE (op1) == INTEGER_CST)
3501 if (tree_int_cst_lt (op1, integer_zero_node))
3503 if (complain & tf_warning)
3504 warning (0, (code == LROTATE_EXPR)
3505 ? G_("left rotate count is negative")
3506 : G_("right rotate count is negative"));
3508 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3510 if (complain & tf_warning)
3511 warning (0, (code == LROTATE_EXPR)
3512 ? G_("left rotate count >= width of type")
3513 : G_("right rotate count >= width of type"));
3516 /* Convert the shift-count to an integer, regardless of
3517 size of value being shifted. */
3518 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3519 op1 = cp_convert (integer_type_node, op1);
3525 if ((complain & tf_warning)
3526 && (FLOAT_TYPE_P (type0) || FLOAT_TYPE_P (type1)))
3527 warning (OPT_Wfloat_equal,
3528 "comparing floating point with == or != is unsafe");
3529 if ((complain & tf_warning)
3530 && ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3531 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0))))
3532 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3534 build_type = boolean_type_node;
3535 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3536 || code0 == COMPLEX_TYPE)
3537 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3538 || code1 == COMPLEX_TYPE))
3540 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3541 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3542 result_type = composite_pointer_type (type0, type1, op0, op1,
3543 "comparison", complain);
3544 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3545 && null_ptr_cst_p (op1))
3547 if (TREE_CODE (op0) == ADDR_EXPR
3548 && decl_with_nonnull_addr_p (TREE_OPERAND (op0, 0)))
3550 if (complain & tf_warning)
3551 warning (OPT_Waddress, "the address of %qD will never be NULL",
3552 TREE_OPERAND (op0, 0));
3554 result_type = type0;
3556 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3557 && null_ptr_cst_p (op0))
3559 if (TREE_CODE (op1) == ADDR_EXPR
3560 && decl_with_nonnull_addr_p (TREE_OPERAND (op1, 0)))
3562 if (complain & tf_warning)
3563 warning (OPT_Waddress, "the address of %qD will never be NULL",
3564 TREE_OPERAND (op1, 0));
3566 result_type = type1;
3568 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3570 result_type = type0;
3571 if (complain & tf_error)
3572 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3574 return error_mark_node;
3576 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3578 result_type = type1;
3579 if (complain & tf_error)
3580 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3582 return error_mark_node;
3584 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3586 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3587 == ptrmemfunc_vbit_in_delta)
3589 tree pfn0 = pfn_from_ptrmemfunc (op0);
3590 tree delta0 = delta_from_ptrmemfunc (op0);
3591 tree e1 = cp_build_binary_op (location,
3594 fold_convert (TREE_TYPE (pfn0),
3597 tree e2 = cp_build_binary_op (location,
3602 e2 = cp_build_binary_op (location,
3603 EQ_EXPR, e2, integer_zero_node,
3605 op0 = cp_build_binary_op (location,
3606 TRUTH_ANDIF_EXPR, e1, e2,
3608 op1 = cp_convert (TREE_TYPE (op0), integer_one_node);
3612 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3613 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3615 result_type = TREE_TYPE (op0);
3617 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3618 return cp_build_binary_op (location, code, op1, op0, complain);
3619 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1))
3622 /* E will be the final comparison. */
3624 /* E1 and E2 are for scratch. */
3632 type = composite_pointer_type (type0, type1, op0, op1, "comparison",
3635 if (!same_type_p (TREE_TYPE (op0), type))
3636 op0 = cp_convert_and_check (type, op0);
3637 if (!same_type_p (TREE_TYPE (op1), type))
3638 op1 = cp_convert_and_check (type, op1);
3640 if (op0 == error_mark_node || op1 == error_mark_node)
3641 return error_mark_node;
3643 if (TREE_SIDE_EFFECTS (op0))
3644 op0 = save_expr (op0);
3645 if (TREE_SIDE_EFFECTS (op1))
3646 op1 = save_expr (op1);
3648 pfn0 = pfn_from_ptrmemfunc (op0);
3649 pfn1 = pfn_from_ptrmemfunc (op1);
3650 delta0 = delta_from_ptrmemfunc (op0);
3651 delta1 = delta_from_ptrmemfunc (op1);
3652 if (TARGET_PTRMEMFUNC_VBIT_LOCATION
3653 == ptrmemfunc_vbit_in_delta)
3658 && ((op0.delta == op1.delta)
3659 || (!op0.pfn && op0.delta & 1 == 0
3660 && op1.delta & 1 == 0))
3662 The reason for the `!op0.pfn' bit is that a NULL
3663 pointer-to-member is any member with a zero PFN and
3664 LSB of the DELTA field is 0. */
3666 e1 = cp_build_binary_op (location, BIT_AND_EXPR,
3670 e1 = cp_build_binary_op (location,
3671 EQ_EXPR, e1, integer_zero_node,
3673 e2 = cp_build_binary_op (location, BIT_AND_EXPR,
3677 e2 = cp_build_binary_op (location,
3678 EQ_EXPR, e2, integer_zero_node,
3680 e1 = cp_build_binary_op (location,
3681 TRUTH_ANDIF_EXPR, e2, e1,
3683 e2 = cp_build_binary_op (location, EQ_EXPR,
3685 fold_convert (TREE_TYPE (pfn0),
3688 e2 = cp_build_binary_op (location,
3689 TRUTH_ANDIF_EXPR, e2, e1, complain);
3690 e1 = cp_build_binary_op (location,
3691 EQ_EXPR, delta0, delta1, complain);
3692 e1 = cp_build_binary_op (location,
3693 TRUTH_ORIF_EXPR, e1, e2, complain);
3700 && (!op0.pfn || op0.delta == op1.delta))
3702 The reason for the `!op0.pfn' bit is that a NULL
3703 pointer-to-member is any member with a zero PFN; the
3704 DELTA field is unspecified. */
3706 e1 = cp_build_binary_op (location,
3707 EQ_EXPR, delta0, delta1, complain);
3708 e2 = cp_build_binary_op (location,
3711 fold_convert (TREE_TYPE (pfn0),
3714 e1 = cp_build_binary_op (location,
3715 TRUTH_ORIF_EXPR, e1, e2, complain);
3717 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3718 e = cp_build_binary_op (location,
3719 TRUTH_ANDIF_EXPR, e2, e1, complain);
3720 if (code == EQ_EXPR)
3722 return cp_build_binary_op (location,
3723 EQ_EXPR, e, integer_zero_node, complain);
3727 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3728 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3730 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3731 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3739 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3740 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3742 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3743 result_type = composite_pointer_type (type0, type1, op0, op1,
3744 "comparison", complain);
3751 if (TREE_CODE (orig_op0) == STRING_CST
3752 || TREE_CODE (orig_op1) == STRING_CST)
3754 if (complain & tf_warning)
3755 warning (OPT_Waddress, "comparison with string literal results in unspecified behaviour");
3758 build_type = boolean_type_node;
3759 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3760 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3762 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3763 result_type = composite_pointer_type (type0, type1, op0, op1,
3764 "comparison", complain);
3765 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3766 && integer_zerop (op1))
3767 result_type = type0;
3768 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3769 && integer_zerop (op0))
3770 result_type = type1;
3771 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3773 result_type = type0;
3774 if (complain & tf_error)
3775 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3777 return error_mark_node;
3779 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3781 result_type = type1;
3782 if (complain & tf_error)
3783 permerror (input_location, "ISO C++ forbids comparison between pointer and integer");
3785 return error_mark_node;
3789 case UNORDERED_EXPR:
3796 build_type = integer_type_node;
3797 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3799 if (complain & tf_error)
3800 error ("unordered comparison on non-floating point argument");
3801 return error_mark_node;
3810 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3811 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3812 || code1 == COMPLEX_TYPE)))
3813 arithmetic_types_p = 1;
3816 arithmetic_types_p = 0;
3817 /* Vector arithmetic is only allowed when both sides are vectors. */
3818 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3820 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3821 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3824 binary_op_error (location, code, type0, type1);
3825 return error_mark_node;
3827 arithmetic_types_p = 1;
3830 /* Determine the RESULT_TYPE, if it is not already known. */
3832 && arithmetic_types_p
3833 && (shorten || common || short_compare))
3834 result_type = cp_common_type (type0, type1);
3838 if (complain & tf_error)
3839 error ("invalid operands of types %qT and %qT to binary %qO",
3840 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3841 return error_mark_node;
3844 /* If we're in a template, the only thing we need to know is the
3846 if (processing_template_decl)
3848 /* Since the middle-end checks the type when doing a build2, we
3849 need to build the tree in pieces. This built tree will never
3850 get out of the front-end as we replace it when instantiating
3852 tree tmp = build2 (resultcode,
3853 build_type ? build_type : result_type,
3855 TREE_OPERAND (tmp, 0) = op0;
3859 if (arithmetic_types_p)
3861 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3863 /* For certain operations (which identify themselves by shorten != 0)
3864 if both args were extended from the same smaller type,
3865 do the arithmetic in that type and then extend.
3867 shorten !=0 and !=1 indicates a bitwise operation.
3868 For them, this optimization is safe only if
3869 both args are zero-extended or both are sign-extended.
3870 Otherwise, we might change the result.
3871 E.g., (short)-1 | (unsigned short)-1 is (int)-1
3872 but calculated in (unsigned short) it would be (unsigned short)-1. */
3874 if (shorten && none_complex)
3876 final_type = result_type;
3877 result_type = shorten_binary_op (result_type, op0, op1,
3881 /* Comparison operations are shortened too but differently.
3882 They identify themselves by setting short_compare = 1. */
3886 /* Don't write &op0, etc., because that would prevent op0
3887 from being kept in a register.
3888 Instead, make copies of the our local variables and
3889 pass the copies by reference, then copy them back afterward. */
3890 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3891 enum tree_code xresultcode = resultcode;
3893 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3895 return cp_convert (boolean_type_node, val);
3896 op0 = xop0, op1 = xop1;
3898 resultcode = xresultcode;
3901 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3902 && warn_sign_compare
3903 /* Do not warn until the template is instantiated; we cannot
3904 bound the ranges of the arguments until that point. */
3905 && !processing_template_decl
3906 && (complain & tf_warning))
3908 warn_for_sign_compare (location, orig_op0, orig_op1, op0, op1,
3909 result_type, resultcode);
3913 /* Issue warnings about peculiar, but valid, uses of NULL. */
3914 if ((orig_op0 == null_node || orig_op1 == null_node)
3915 /* It's reasonable to use pointer values as operands of &&
3916 and ||, so NULL is no exception. */
3917 && code != TRUTH_ANDIF_EXPR && code != TRUTH_ORIF_EXPR
3918 && ( /* Both are NULL (or 0) and the operation was not a comparison. */
3919 (null_ptr_cst_p (orig_op0) && null_ptr_cst_p (orig_op1)
3920 && code != EQ_EXPR && code != NE_EXPR)
3921 /* Or if one of OP0 or OP1 is neither a pointer nor NULL. */
3922 || (!null_ptr_cst_p (orig_op0) && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3923 || (!null_ptr_cst_p (orig_op1) && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE))
3924 && (complain & tf_warning))
3925 /* Some sort of arithmetic operation involving NULL was
3926 performed. Note that pointer-difference and pointer-addition
3927 have already been handled above, and so we don't end up here in
3929 warning (OPT_Wpointer_arith, "NULL used in arithmetic");
3932 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3933 Then the expression will be built.
3934 It will be given type FINAL_TYPE if that is nonzero;
3935 otherwise, it will be given type RESULT_TYPE. */
3938 if (TREE_TYPE (op0) != result_type)
3939 op0 = cp_convert_and_check (result_type, op0);
3940 if (TREE_TYPE (op1) != result_type)
3941 op1 = cp_convert_and_check (result_type, op1);
3943 if (op0 == error_mark_node || op1 == error_mark_node)
3944 return error_mark_node;
3947 if (build_type == NULL_TREE)
3948 build_type = result_type;
3950 result = build2 (resultcode, build_type, op0, op1);
3951 result = fold_if_not_in_template (result);
3952 if (final_type != 0)
3953 result = cp_convert (final_type, result);
3955 if (TREE_OVERFLOW_P (result)
3956 && !TREE_OVERFLOW_P (op0)
3957 && !TREE_OVERFLOW_P (op1))
3958 overflow_warning (result);
3963 /* Return a tree for the sum or difference (RESULTCODE says which)
3964 of pointer PTROP and integer INTOP. */
3967 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
3969 tree res_type = TREE_TYPE (ptrop);
3971 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3972 in certain circumstance (when it's valid to do so). So we need
3973 to make sure it's complete. We don't need to check here, if we
3974 can actually complete it at all, as those checks will be done in
3975 pointer_int_sum() anyway. */
3976 complete_type (TREE_TYPE (res_type));
3978 return pointer_int_sum (resultcode, ptrop,
3979 fold_if_not_in_template (intop));
3982 /* Return a tree for the difference of pointers OP0 and OP1.
3983 The resulting tree has type int. */
3986 pointer_diff (tree op0, tree op1, tree ptrtype)
3989 tree restype = ptrdiff_type_node;
3990 tree target_type = TREE_TYPE (ptrtype);
3992 if (!complete_type_or_else (target_type, NULL_TREE))
3993 return error_mark_node;
3995 if (TREE_CODE (target_type) == VOID_TYPE)
3996 permerror (input_location, "ISO C++ forbids using pointer of type %<void *%> in subtraction");
3997 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3998 permerror (input_location, "ISO C++ forbids using pointer to a function in subtraction");
3999 if (TREE_CODE (target_type) == METHOD_TYPE)
4000 permerror (input_location, "ISO C++ forbids using pointer to a method in subtraction");
4002 /* First do the subtraction as integers;
4003 then drop through to build the divide operator. */
4005 op0 = cp_build_binary_op (input_location,
4007 cp_convert (restype, op0),
4008 cp_convert (restype, op1),
4009 tf_warning_or_error);
4011 /* This generates an error if op1 is a pointer to an incomplete type. */
4012 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
4013 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
4015 op1 = (TYPE_PTROB_P (ptrtype)
4016 ? size_in_bytes (target_type)
4017 : integer_one_node);
4019 /* Do the division. */
4021 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
4022 return fold_if_not_in_template (result);
4025 /* Construct and perhaps optimize a tree representation
4026 for a unary operation. CODE, a tree_code, specifies the operation
4027 and XARG is the operand. */
4030 build_x_unary_op (enum tree_code code, tree xarg, tsubst_flags_t complain)
4032 tree orig_expr = xarg;
4036 if (processing_template_decl)
4038 if (type_dependent_expression_p (xarg))
4039 return build_min_nt (code, xarg, NULL_TREE);
4041 xarg = build_non_dependent_expr (xarg);
4046 /* [expr.unary.op] says:
4048 The address of an object of incomplete type can be taken.
4050 (And is just the ordinary address operator, not an overloaded
4051 "operator &".) However, if the type is a template
4052 specialization, we must complete the type at this point so that
4053 an overloaded "operator &" will be available if required. */
4054 if (code == ADDR_EXPR
4055 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
4056 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
4057 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
4058 || (TREE_CODE (xarg) == OFFSET_REF)))
4059 /* Don't look for a function. */;
4061 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
4062 /*overloaded_p=*/NULL, complain);
4063 if (!exp && code == ADDR_EXPR)
4065 /* A pointer to member-function can be formed only by saying
4067 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
4068 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
4070 if (TREE_CODE (xarg) != OFFSET_REF
4071 || !TYPE_P (TREE_OPERAND (xarg, 0)))
4073 error ("invalid use of %qE to form a pointer-to-member-function",
4075 if (TREE_CODE (xarg) != OFFSET_REF)
4076 inform (input_location, " a qualified-id is required");
4077 return error_mark_node;
4081 error ("parentheses around %qE cannot be used to form a"
4082 " pointer-to-member-function",
4084 PTRMEM_OK_P (xarg) = 1;
4088 if (TREE_CODE (xarg) == OFFSET_REF)
4090 ptrmem = PTRMEM_OK_P (xarg);
4092 if (!ptrmem && !flag_ms_extensions
4093 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
4095 /* A single non-static member, make sure we don't allow a
4096 pointer-to-member. */
4097 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
4098 TREE_OPERAND (xarg, 0),
4099 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
4100 PTRMEM_OK_P (xarg) = ptrmem;
4103 else if (TREE_CODE (xarg) == TARGET_EXPR && (complain & tf_warning))
4104 warning (0, "taking address of temporary");
4105 exp = cp_build_unary_op (ADDR_EXPR, xarg, 0, complain);
4108 if (processing_template_decl && exp != error_mark_node)
4109 exp = build_min_non_dep (code, exp, orig_expr,
4110 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
4111 if (TREE_CODE (exp) == ADDR_EXPR)
4112 PTRMEM_OK_P (exp) = ptrmem;
4116 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
4117 constants, where a null value is represented by an INTEGER_CST of
4121 cp_truthvalue_conversion (tree expr)
4123 tree type = TREE_TYPE (expr);
4124 if (TYPE_PTRMEM_P (type))
4125 return build_binary_op (EXPR_LOCATION (expr),
4126 NE_EXPR, expr, integer_zero_node, 1);
4128 return c_common_truthvalue_conversion (input_location, expr);
4131 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
4134 condition_conversion (tree expr)
4137 if (processing_template_decl)
4139 t = perform_implicit_conversion (boolean_type_node, expr,
4140 tf_warning_or_error);
4141 t = fold_build_cleanup_point_expr (boolean_type_node, t);
4145 /* Return an ADDR_EXPR giving the address of T. This function
4146 attempts no optimizations or simplifications; it is a low-level
4150 build_address (tree t)
4154 if (error_operand_p (t) || !cxx_mark_addressable (t))
4155 return error_mark_node;
4157 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
4162 /* Return a NOP_EXPR converting EXPR to TYPE. */
4165 build_nop (tree type, tree expr)
4167 if (type == error_mark_node || error_operand_p (expr))
4169 return build1 (NOP_EXPR, type, expr);
4172 /* C++: Must handle pointers to members.
4174 Perhaps type instantiation should be extended to handle conversion
4175 from aggregates to types we don't yet know we want? (Or are those
4176 cases typically errors which should be reported?)
4178 NOCONVERT nonzero suppresses the default promotions
4179 (such as from short to int). */
4182 cp_build_unary_op (enum tree_code code, tree xarg, int noconvert,
4183 tsubst_flags_t complain)
4185 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
4188 const char *errstring = NULL;
4190 const char *invalid_op_diag;
4192 if (error_operand_p (arg))
4193 return error_mark_node;
4195 if ((invalid_op_diag
4196 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
4201 error (invalid_op_diag);
4202 return error_mark_node;
4207 case UNARY_PLUS_EXPR:
4210 int flags = WANT_ARITH | WANT_ENUM;
4211 /* Unary plus (but not unary minus) is allowed on pointers. */
4212 if (code == UNARY_PLUS_EXPR)
4213 flags |= WANT_POINTER;
4214 arg = build_expr_type_conversion (flags, arg, true);
4216 errstring = (code == NEGATE_EXPR
4217 ? "wrong type argument to unary minus"
4218 : "wrong type argument to unary plus");
4221 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4222 arg = perform_integral_promotions (arg);
4224 /* Make sure the result is not an lvalue: a unary plus or minus
4225 expression is always a rvalue. */
4232 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4236 arg = default_conversion (arg);
4238 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM
4241 errstring = "wrong type argument to bit-complement";
4242 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4243 arg = perform_integral_promotions (arg);
4247 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4248 errstring = "wrong type argument to abs";
4249 else if (!noconvert)
4250 arg = default_conversion (arg);
4254 /* Conjugating a real value is a no-op, but allow it anyway. */
4255 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4256 errstring = "wrong type argument to conjugation";
4257 else if (!noconvert)
4258 arg = default_conversion (arg);
4261 case TRUTH_NOT_EXPR:
4262 arg = perform_implicit_conversion (boolean_type_node, arg,
4264 val = invert_truthvalue (arg);
4265 if (arg != error_mark_node)
4267 errstring = "in argument to unary !";
4274 if (TREE_CODE (arg) == COMPLEX_CST)
4275 return TREE_REALPART (arg);
4276 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4278 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4279 return fold_if_not_in_template (arg);
4285 if (TREE_CODE (arg) == COMPLEX_CST)
4286 return TREE_IMAGPART (arg);
4287 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4289 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4290 return fold_if_not_in_template (arg);
4293 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4295 case PREINCREMENT_EXPR:
4296 case POSTINCREMENT_EXPR:
4297 case PREDECREMENT_EXPR:
4298 case POSTDECREMENT_EXPR:
4299 /* Handle complex lvalues (when permitted)
4300 by reduction to simpler cases. */
4302 val = unary_complex_lvalue (code, arg);
4306 /* Increment or decrement the real part of the value,
4307 and don't change the imaginary part. */
4308 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4312 arg = stabilize_reference (arg);
4313 real = cp_build_unary_op (REALPART_EXPR, arg, 1, complain);
4314 imag = cp_build_unary_op (IMAGPART_EXPR, arg, 1, complain);
4315 real = cp_build_unary_op (code, real, 1, complain);
4316 if (real == error_mark_node || imag == error_mark_node)
4317 return error_mark_node;
4318 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4322 /* Report invalid types. */
4324 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4327 if (code == PREINCREMENT_EXPR)
4328 errstring ="no pre-increment operator for type";
4329 else if (code == POSTINCREMENT_EXPR)
4330 errstring ="no post-increment operator for type";
4331 else if (code == PREDECREMENT_EXPR)
4332 errstring ="no pre-decrement operator for type";
4334 errstring ="no post-decrement operator for type";
4337 else if (arg == error_mark_node)
4338 return error_mark_node;
4340 /* Report something read-only. */
4342 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4343 || TREE_READONLY (arg))
4345 if (complain & tf_error)
4346 readonly_error (arg, ((code == PREINCREMENT_EXPR
4347 || code == POSTINCREMENT_EXPR)
4348 ? "increment" : "decrement"));
4350 return error_mark_node;
4355 tree declared_type = unlowered_expr_type (arg);
4357 argtype = TREE_TYPE (arg);
4359 /* ARM $5.2.5 last annotation says this should be forbidden. */
4360 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4362 if (complain & tf_error)
4363 permerror (input_location, (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4364 ? G_("ISO C++ forbids incrementing an enum")
4365 : G_("ISO C++ forbids decrementing an enum"));
4367 return error_mark_node;
4370 /* Compute the increment. */
4372 if (TREE_CODE (argtype) == POINTER_TYPE)
4374 tree type = complete_type (TREE_TYPE (argtype));
4376 if (!COMPLETE_OR_VOID_TYPE_P (type))
4378 if (complain & tf_error)
4379 error (((code == PREINCREMENT_EXPR
4380 || code == POSTINCREMENT_EXPR))
4381 ? G_("cannot increment a pointer to incomplete type %qT")
4382 : G_("cannot decrement a pointer to incomplete type %qT"),
4383 TREE_TYPE (argtype));
4385 return error_mark_node;
4387 else if ((pedantic || warn_pointer_arith)
4388 && !TYPE_PTROB_P (argtype))
4390 if (complain & tf_error)
4391 permerror (input_location, (code == PREINCREMENT_EXPR
4392 || code == POSTINCREMENT_EXPR)
4393 ? G_("ISO C++ forbids incrementing a pointer of type %qT")
4394 : G_("ISO C++ forbids decrementing a pointer of type %qT"),
4397 return error_mark_node;
4400 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4403 inc = integer_one_node;
4405 inc = cp_convert (argtype, inc);
4407 /* Complain about anything else that is not a true lvalue. */
4408 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4409 || code == POSTINCREMENT_EXPR)
4410 ? lv_increment : lv_decrement),
4412 return error_mark_node;
4414 /* Forbid using -- on `bool'. */
4415 if (same_type_p (declared_type, boolean_type_node))
4417 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4419 if (complain & tf_error)
4420 error ("invalid use of Boolean expression as operand "
4421 "to %<operator--%>");
4422 return error_mark_node;
4424 val = boolean_increment (code, arg);
4427 val = build2 (code, TREE_TYPE (arg), arg, inc);
4429 TREE_SIDE_EFFECTS (val) = 1;
4434 /* Note that this operation never does default_conversion
4435 regardless of NOCONVERT. */
4437 argtype = lvalue_type (arg);
4439 if (TREE_CODE (arg) == OFFSET_REF)
4442 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4444 tree type = build_pointer_type (TREE_TYPE (argtype));
4445 arg = build1 (CONVERT_EXPR, type, arg);
4448 else if (DECL_MAIN_P (arg))
4451 if (complain & tf_error)
4452 permerror (input_location, "ISO C++ forbids taking address of function %<::main%>");
4454 return error_mark_node;
4457 /* Let &* cancel out to simplify resulting code. */
4458 if (TREE_CODE (arg) == INDIRECT_REF)
4460 /* We don't need to have `current_class_ptr' wrapped in a
4461 NON_LVALUE_EXPR node. */
4462 if (arg == current_class_ref)
4463 return current_class_ptr;
4465 arg = TREE_OPERAND (arg, 0);
4466 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4468 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4469 arg = build1 (CONVERT_EXPR, type, arg);
4472 /* Don't let this be an lvalue. */
4477 /* Uninstantiated types are all functions. Taking the
4478 address of a function is a no-op, so just return the
4481 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4482 || !IDENTIFIER_OPNAME_P (arg));
4484 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4485 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4487 /* They're trying to take the address of a unique non-static
4488 member function. This is ill-formed (except in MS-land),
4489 but let's try to DTRT.
4490 Note: We only handle unique functions here because we don't
4491 want to complain if there's a static overload; non-unique
4492 cases will be handled by instantiate_type. But we need to
4493 handle this case here to allow casts on the resulting PMF.
4494 We could defer this in non-MS mode, but it's easier to give
4495 a useful error here. */
4497 /* Inside constant member functions, the `this' pointer
4498 contains an extra const qualifier. TYPE_MAIN_VARIANT
4499 is used here to remove this const from the diagnostics
4500 and the created OFFSET_REF. */
4501 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4502 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4505 if (! flag_ms_extensions)
4507 tree name = DECL_NAME (fn);
4508 if (!(complain & tf_error))
4509 return error_mark_node;
4510 else if (current_class_type
4511 && TREE_OPERAND (arg, 0) == current_class_ref)
4512 /* An expression like &memfn. */
4513 permerror (input_location, "ISO C++ forbids taking the address of an unqualified"
4514 " or parenthesized non-static member function to form"
4515 " a pointer to member function. Say %<&%T::%D%>",
4518 permerror (input_location, "ISO C++ forbids taking the address of a bound member"
4519 " function to form a pointer to member function."
4523 arg = build_offset_ref (base, fn, /*address_p=*/true);
4527 if (type_unknown_p (arg))
4528 return build1 (ADDR_EXPR, unknown_type_node, arg);
4530 /* Handle complex lvalues (when permitted)
4531 by reduction to simpler cases. */
4532 val = unary_complex_lvalue (code, arg);
4536 switch (TREE_CODE (arg))
4540 case FIX_TRUNC_EXPR:
4541 /* Even if we're not being pedantic, we cannot allow this
4542 extension when we're instantiating in a SFINAE
4544 if (! lvalue_p (arg) && complain == tf_none)
4546 if (complain & tf_error)
4547 permerror (input_location, "ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4549 return error_mark_node;
4554 arg = BASELINK_FUNCTIONS (arg);
4558 arg = OVL_CURRENT (arg);
4562 /* Turn a reference to a non-static data member into a
4563 pointer-to-member. */
4568 if (!PTRMEM_OK_P (arg))
4569 return cp_build_unary_op (code, arg, 0, complain);
4571 t = TREE_OPERAND (arg, 1);
4572 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4574 if (complain & tf_error)
4575 error ("cannot create pointer to reference member %qD", t);
4576 return error_mark_node;
4579 type = build_ptrmem_type (context_for_name_lookup (t),
4581 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4589 /* Anything not already handled and not a true memory reference
4591 if (TREE_CODE (argtype) != FUNCTION_TYPE
4592 && TREE_CODE (argtype) != METHOD_TYPE
4593 && TREE_CODE (arg) != OFFSET_REF
4594 && !lvalue_or_else (arg, lv_addressof, complain))
4595 return error_mark_node;
4597 if (argtype != error_mark_node)
4598 argtype = build_pointer_type (argtype);
4600 /* In a template, we are processing a non-dependent expression
4601 so we can just form an ADDR_EXPR with the correct type. */
4602 if (processing_template_decl || TREE_CODE (arg) != COMPONENT_REF)
4604 val = build_address (arg);
4605 if (TREE_CODE (arg) == OFFSET_REF)
4606 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4608 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4610 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4612 /* We can only get here with a single static member
4614 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4615 && DECL_STATIC_FUNCTION_P (fn));
4617 val = build_address (fn);
4618 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4619 /* Do not lose object's side effects. */
4620 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4621 TREE_OPERAND (arg, 0), val);
4623 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4625 if (complain & tf_error)
4626 error ("attempt to take address of bit-field structure member %qD",
4627 TREE_OPERAND (arg, 1));
4628 return error_mark_node;
4632 tree object = TREE_OPERAND (arg, 0);
4633 tree field = TREE_OPERAND (arg, 1);
4634 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4635 (TREE_TYPE (object), decl_type_context (field)));
4636 val = build_address (arg);
4639 if (TREE_CODE (argtype) == POINTER_TYPE
4640 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4642 build_ptrmemfunc_type (argtype);
4643 val = build_ptrmemfunc (argtype, val, 0,
4644 /*c_cast_p=*/false);
4656 argtype = TREE_TYPE (arg);
4657 return fold_if_not_in_template (build1 (code, argtype, arg));
4660 if (complain & tf_error)
4661 error ("%s", errstring);
4662 return error_mark_node;
4665 /* Hook for the c-common bits that build a unary op. */
4667 build_unary_op (location_t location ATTRIBUTE_UNUSED,
4668 enum tree_code code, tree xarg, int noconvert)
4670 return cp_build_unary_op (code, xarg, noconvert, tf_warning_or_error);
4673 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4674 for certain kinds of expressions which are not really lvalues
4675 but which we can accept as lvalues.
4677 If ARG is not a kind of expression we can handle, return
4681 unary_complex_lvalue (enum tree_code code, tree arg)
4683 /* Inside a template, making these kinds of adjustments is
4684 pointless; we are only concerned with the type of the
4686 if (processing_template_decl)
4689 /* Handle (a, b) used as an "lvalue". */
4690 if (TREE_CODE (arg) == COMPOUND_EXPR)
4692 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 1), 0,
4693 tf_warning_or_error);
4694 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4695 TREE_OPERAND (arg, 0), real_result);
4698 /* Handle (a ? b : c) used as an "lvalue". */
4699 if (TREE_CODE (arg) == COND_EXPR
4700 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4701 return rationalize_conditional_expr (code, arg, tf_warning_or_error);
4703 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4704 if (TREE_CODE (arg) == MODIFY_EXPR
4705 || TREE_CODE (arg) == PREINCREMENT_EXPR
4706 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4708 tree lvalue = TREE_OPERAND (arg, 0);
4709 if (TREE_SIDE_EFFECTS (lvalue))
4711 lvalue = stabilize_reference (lvalue);
4712 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4713 lvalue, TREE_OPERAND (arg, 1));
4715 return unary_complex_lvalue
4716 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4719 if (code != ADDR_EXPR)
4722 /* Handle (a = b) used as an "lvalue" for `&'. */
4723 if (TREE_CODE (arg) == MODIFY_EXPR
4724 || TREE_CODE (arg) == INIT_EXPR)
4726 tree real_result = cp_build_unary_op (code, TREE_OPERAND (arg, 0), 0,
4727 tf_warning_or_error);
4728 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4730 TREE_NO_WARNING (arg) = 1;
4734 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4735 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4736 || TREE_CODE (arg) == OFFSET_REF)
4739 /* We permit compiler to make function calls returning
4740 objects of aggregate type look like lvalues. */
4744 if (TREE_CODE (targ) == SAVE_EXPR)
4745 targ = TREE_OPERAND (targ, 0);
4747 if (TREE_CODE (targ) == CALL_EXPR && MAYBE_CLASS_TYPE_P (TREE_TYPE (targ)))
4749 if (TREE_CODE (arg) == SAVE_EXPR)
4752 targ = build_cplus_new (TREE_TYPE (arg), arg);
4753 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4756 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4757 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4758 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4761 /* Don't let anything else be handled specially. */
4765 /* Mark EXP saying that we need to be able to take the
4766 address of it; it should not be allocated in a register.
4767 Value is true if successful.
4769 C++: we do not allow `current_class_ptr' to be addressable. */
4772 cxx_mark_addressable (tree exp)
4777 switch (TREE_CODE (x))
4784 x = TREE_OPERAND (x, 0);
4788 if (x == current_class_ptr)
4790 error ("cannot take the address of %<this%>, which is an rvalue expression");
4791 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4797 /* Caller should not be trying to mark initialized
4798 constant fields addressable. */
4799 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4800 || DECL_IN_AGGR_P (x) == 0
4802 || DECL_EXTERNAL (x));
4807 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4808 && !DECL_ARTIFICIAL (x))
4810 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4813 ("address of explicit register variable %qD requested", x);
4816 else if (extra_warnings)
4818 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
4820 TREE_ADDRESSABLE (x) = 1;
4824 TREE_ADDRESSABLE (x) = 1;
4828 TREE_ADDRESSABLE (x) = 1;
4832 TREE_ADDRESSABLE (x) = 1;
4833 cxx_mark_addressable (TREE_OPERAND (x, 0));
4841 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4844 build_x_conditional_expr (tree ifexp, tree op1, tree op2,
4845 tsubst_flags_t complain)
4847 tree orig_ifexp = ifexp;
4848 tree orig_op1 = op1;
4849 tree orig_op2 = op2;
4852 if (processing_template_decl)
4854 /* The standard says that the expression is type-dependent if
4855 IFEXP is type-dependent, even though the eventual type of the
4856 expression doesn't dependent on IFEXP. */
4857 if (type_dependent_expression_p (ifexp)
4858 /* As a GNU extension, the middle operand may be omitted. */
4859 || (op1 && type_dependent_expression_p (op1))
4860 || type_dependent_expression_p (op2))
4861 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4862 ifexp = build_non_dependent_expr (ifexp);
4864 op1 = build_non_dependent_expr (op1);
4865 op2 = build_non_dependent_expr (op2);
4868 expr = build_conditional_expr (ifexp, op1, op2, complain);
4869 if (processing_template_decl && expr != error_mark_node)
4870 return build_min_non_dep (COND_EXPR, expr,
4871 orig_ifexp, orig_op1, orig_op2);
4875 /* Given a list of expressions, return a compound expression
4876 that performs them all and returns the value of the last of them. */
4878 tree build_x_compound_expr_from_list (tree list, const char *msg)
4880 tree expr = TREE_VALUE (list);
4882 if (TREE_CHAIN (list))
4885 permerror (input_location, "%s expression list treated as compound expression", msg);
4887 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4888 expr = build_x_compound_expr (expr, TREE_VALUE (list),
4889 tf_warning_or_error);
4895 /* Handle overloading of the ',' operator when needed. */
4898 build_x_compound_expr (tree op1, tree op2, tsubst_flags_t complain)
4901 tree orig_op1 = op1;
4902 tree orig_op2 = op2;
4904 if (processing_template_decl)
4906 if (type_dependent_expression_p (op1)
4907 || type_dependent_expression_p (op2))
4908 return build_min_nt (COMPOUND_EXPR, op1, op2);
4909 op1 = build_non_dependent_expr (op1);
4910 op2 = build_non_dependent_expr (op2);
4913 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4914 /*overloaded_p=*/NULL, complain);
4916 result = cp_build_compound_expr (op1, op2, complain);
4918 if (processing_template_decl && result != error_mark_node)
4919 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4924 /* Like cp_build_compound_expr, but for the c-common bits. */
4927 build_compound_expr (tree lhs, tree rhs)
4929 return cp_build_compound_expr (lhs, rhs, tf_warning_or_error);
4932 /* Build a compound expression. */
4935 cp_build_compound_expr (tree lhs, tree rhs, tsubst_flags_t complain)
4937 lhs = convert_to_void (lhs, "left-hand operand of comma", complain);
4939 if (lhs == error_mark_node || rhs == error_mark_node)
4940 return error_mark_node;
4942 if (TREE_CODE (rhs) == TARGET_EXPR)
4944 /* If the rhs is a TARGET_EXPR, then build the compound
4945 expression inside the target_expr's initializer. This
4946 helps the compiler to eliminate unnecessary temporaries. */
4947 tree init = TREE_OPERAND (rhs, 1);
4949 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4950 TREE_OPERAND (rhs, 1) = init;
4955 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4958 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
4959 casts away constness. CAST gives the type of cast. */
4962 check_for_casting_away_constness (tree src_type, tree dest_type,
4963 enum tree_code cast)
4965 /* C-style casts are allowed to cast away constness. With
4966 WARN_CAST_QUAL, we still want to issue a warning. */
4967 if (cast == CAST_EXPR && !warn_cast_qual)
4970 if (casts_away_constness (src_type, dest_type))
4974 warning (OPT_Wcast_qual,
4975 "cast from type %qT to type %qT casts away constness",
4976 src_type, dest_type);
4979 case STATIC_CAST_EXPR:
4980 error ("static_cast from type %qT to type %qT casts away constness",
4981 src_type, dest_type);
4984 case REINTERPRET_CAST_EXPR:
4985 error ("reinterpret_cast from type %qT to type %qT casts away constness",
4986 src_type, dest_type);
4993 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
4994 (another pointer-to-member type in the same hierarchy) and return
4995 the converted expression. If ALLOW_INVERSE_P is permitted, a
4996 pointer-to-derived may be converted to pointer-to-base; otherwise,
4997 only the other direction is permitted. If C_CAST_P is true, this
4998 conversion is taking place as part of a C-style cast. */
5001 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
5004 if (TYPE_PTRMEM_P (type))
5008 if (TREE_CODE (expr) == PTRMEM_CST)
5009 expr = cplus_expand_constant (expr);
5010 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
5011 TYPE_PTRMEM_CLASS_TYPE (type),
5014 if (!integer_zerop (delta))
5016 tree cond, op1, op2;
5018 cond = cp_build_binary_op (input_location,
5021 build_int_cst (TREE_TYPE (expr), -1),
5022 tf_warning_or_error);
5023 op1 = build_nop (ptrdiff_type_node, expr);
5024 op2 = cp_build_binary_op (input_location,
5025 PLUS_EXPR, op1, delta,
5026 tf_warning_or_error);
5028 expr = fold_build3 (COND_EXPR, ptrdiff_type_node, cond, op1, op2);
5032 return build_nop (type, expr);
5035 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
5036 allow_inverse_p, c_cast_p);
5039 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
5040 a version of EXPR that has TREE_OVERFLOW set if it is set in ORIG.
5041 Otherwise, return EXPR unchanged. */
5044 ignore_overflows (tree expr, tree orig)
5046 if (TREE_CODE (expr) == INTEGER_CST
5047 && CONSTANT_CLASS_P (orig)
5048 && TREE_CODE (orig) != STRING_CST
5049 && TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig))
5051 if (!TREE_OVERFLOW (orig))
5052 /* Ensure constant sharing. */
5053 expr = build_int_cst_wide (TREE_TYPE (expr),
5054 TREE_INT_CST_LOW (expr),
5055 TREE_INT_CST_HIGH (expr));
5058 /* Avoid clobbering a shared constant. */
5059 expr = copy_node (expr);
5060 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
5066 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
5067 this static_cast is being attempted as one of the possible casts
5068 allowed by a C-style cast. (In that case, accessibility of base
5069 classes is not considered, and it is OK to cast away
5070 constness.) Return the result of the cast. *VALID_P is set to
5071 indicate whether or not the cast was valid. */
5074 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
5075 bool *valid_p, tsubst_flags_t complain)
5081 /* Assume the cast is valid. */
5084 intype = TREE_TYPE (expr);
5086 /* Save casted types in the function's used types hash table. */
5087 used_types_insert (type);
5089 /* [expr.static.cast]
5091 An lvalue of type "cv1 B", where B is a class type, can be cast
5092 to type "reference to cv2 D", where D is a class derived (clause
5093 _class.derived_) from B, if a valid standard conversion from
5094 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
5095 same cv-qualification as, or greater cv-qualification than, cv1,
5096 and B is not a virtual base class of D. */
5097 /* We check this case before checking the validity of "TYPE t =
5098 EXPR;" below because for this case:
5101 struct D : public B { D(const B&); };
5103 void f() { static_cast<const D&>(b); }
5105 we want to avoid constructing a new D. The standard is not
5106 completely clear about this issue, but our interpretation is
5107 consistent with other compilers. */
5108 if (TREE_CODE (type) == REFERENCE_TYPE
5109 && CLASS_TYPE_P (TREE_TYPE (type))
5110 && CLASS_TYPE_P (intype)
5111 && real_lvalue_p (expr)
5112 && DERIVED_FROM_P (intype, TREE_TYPE (type))
5113 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
5114 build_pointer_type (TYPE_MAIN_VARIANT
5115 (TREE_TYPE (type))))
5117 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
5121 /* There is a standard conversion from "D*" to "B*" even if "B"
5122 is ambiguous or inaccessible. If this is really a
5123 static_cast, then we check both for inaccessibility and
5124 ambiguity. However, if this is a static_cast being performed
5125 because the user wrote a C-style cast, then accessibility is
5127 base = lookup_base (TREE_TYPE (type), intype,
5128 c_cast_p ? ba_unique : ba_check,
5131 /* Convert from "B*" to "D*". This function will check that "B"
5132 is not a virtual base of "D". */
5133 expr = build_base_path (MINUS_EXPR, build_address (expr),
5134 base, /*nonnull=*/false);
5135 /* Convert the pointer to a reference -- but then remember that
5136 there are no expressions with reference type in C++. */
5137 return convert_from_reference (build_nop (type, expr));
5142 /* [expr.static.cast]
5144 An expression e can be explicitly converted to a type T using a
5145 static_cast of the form static_cast<T>(e) if the declaration T
5146 t(e);" is well-formed, for some invented temporary variable
5148 result = perform_direct_initialization_if_possible (type, expr,
5149 c_cast_p, complain);
5152 result = convert_from_reference (result);
5154 /* Ignore any integer overflow caused by the cast. */
5155 result = ignore_overflows (result, orig);
5157 /* [expr.static.cast]
5159 If T is a reference type, the result is an lvalue; otherwise,
5160 the result is an rvalue. */
5161 if (TREE_CODE (type) != REFERENCE_TYPE)
5162 result = rvalue (result);
5166 /* [expr.static.cast]
5168 Any expression can be explicitly converted to type cv void. */
5169 if (TREE_CODE (type) == VOID_TYPE)
5170 return convert_to_void (expr, /*implicit=*/NULL, complain);
5172 /* [expr.static.cast]
5174 The inverse of any standard conversion sequence (clause _conv_),
5175 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
5176 (_conv.array_), function-to-pointer (_conv.func_), and boolean
5177 (_conv.bool_) conversions, can be performed explicitly using
5178 static_cast subject to the restriction that the explicit
5179 conversion does not cast away constness (_expr.const.cast_), and
5180 the following additional rules for specific cases: */
5181 /* For reference, the conversions not excluded are: integral
5182 promotions, floating point promotion, integral conversions,
5183 floating point conversions, floating-integral conversions,
5184 pointer conversions, and pointer to member conversions. */
5187 A value of integral _or enumeration_ type can be explicitly
5188 converted to an enumeration type. */
5189 /* The effect of all that is that any conversion between any two
5190 types which are integral, floating, or enumeration types can be
5192 if ((INTEGRAL_TYPE_P (type) || SCALAR_FLOAT_TYPE_P (type))
5193 && (INTEGRAL_TYPE_P (intype) || SCALAR_FLOAT_TYPE_P (intype)))
5195 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
5197 /* Ignore any integer overflow caused by the cast. */
5198 expr = ignore_overflows (expr, orig);
5202 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
5203 && CLASS_TYPE_P (TREE_TYPE (type))
5204 && CLASS_TYPE_P (TREE_TYPE (intype))
5205 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
5206 (TREE_TYPE (intype))),
5207 build_pointer_type (TYPE_MAIN_VARIANT
5208 (TREE_TYPE (type)))))
5213 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5214 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
5215 c_cast_p ? ba_unique : ba_check,
5217 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
5220 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5221 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5228 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
5229 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
5231 if (TYPE_PTRMEM_P (type))
5233 t1 = (build_ptrmem_type
5235 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
5236 t2 = (build_ptrmem_type
5238 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
5245 if (can_convert (t1, t2) || can_convert (t2, t1))
5248 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5249 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
5254 /* [expr.static.cast]
5256 An rvalue of type "pointer to cv void" can be explicitly
5257 converted to a pointer to object type. A value of type pointer
5258 to object converted to "pointer to cv void" and back to the
5259 original pointer type will have its original value. */
5260 if (TREE_CODE (intype) == POINTER_TYPE
5261 && VOID_TYPE_P (TREE_TYPE (intype))
5262 && TYPE_PTROB_P (type))
5265 check_for_casting_away_constness (intype, type, STATIC_CAST_EXPR);
5266 return build_nop (type, expr);
5270 return error_mark_node;
5273 /* Return an expression representing static_cast<TYPE>(EXPR). */
5276 build_static_cast (tree type, tree expr, tsubst_flags_t complain)
5281 if (type == error_mark_node || expr == error_mark_node)
5282 return error_mark_node;
5284 if (processing_template_decl)
5286 expr = build_min (STATIC_CAST_EXPR, type, expr);
5287 /* We don't know if it will or will not have side effects. */
5288 TREE_SIDE_EFFECTS (expr) = 1;
5289 return convert_from_reference (expr);
5292 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5293 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5294 if (TREE_CODE (type) != REFERENCE_TYPE
5295 && TREE_CODE (expr) == NOP_EXPR
5296 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5297 expr = TREE_OPERAND (expr, 0);
5299 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p,
5304 if (complain & tf_error)
5305 error ("invalid static_cast from type %qT to type %qT",
5306 TREE_TYPE (expr), type);
5307 return error_mark_node;
5310 /* EXPR is an expression with member function or pointer-to-member
5311 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5312 not permitted by ISO C++, but we accept it in some modes. If we
5313 are not in one of those modes, issue a diagnostic. Return the
5314 converted expression. */
5317 convert_member_func_to_ptr (tree type, tree expr)
5322 intype = TREE_TYPE (expr);
5323 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
5324 || TREE_CODE (intype) == METHOD_TYPE);
5326 if (pedantic || warn_pmf2ptr)
5327 pedwarn (input_location, pedantic ? OPT_pedantic : OPT_Wpmf_conversions,
5328 "converting from %qT to %qT", intype, type);
5330 if (TREE_CODE (intype) == METHOD_TYPE)
5331 expr = build_addr_func (expr);
5332 else if (TREE_CODE (expr) == PTRMEM_CST)
5333 expr = build_address (PTRMEM_CST_MEMBER (expr));
5336 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
5337 decl = build_address (decl);
5338 expr = get_member_function_from_ptrfunc (&decl, expr);
5341 return build_nop (type, expr);
5344 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5345 If C_CAST_P is true, this reinterpret cast is being done as part of
5346 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5347 indicate whether or not reinterpret_cast was valid. */
5350 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5351 bool *valid_p, tsubst_flags_t complain)
5355 /* Assume the cast is invalid. */
5359 if (type == error_mark_node || error_operand_p (expr))
5360 return error_mark_node;
5362 intype = TREE_TYPE (expr);
5364 /* Save casted types in the function's used types hash table. */
5365 used_types_insert (type);
5367 /* [expr.reinterpret.cast]
5368 An lvalue expression of type T1 can be cast to the type
5369 "reference to T2" if an expression of type "pointer to T1" can be
5370 explicitly converted to the type "pointer to T2" using a
5371 reinterpret_cast. */
5372 if (TREE_CODE (type) == REFERENCE_TYPE)
5374 if (! real_lvalue_p (expr))
5376 if (complain & tf_error)
5377 error ("invalid cast of an rvalue expression of type "
5380 return error_mark_node;
5383 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5384 "B" are related class types; the reinterpret_cast does not
5385 adjust the pointer. */
5386 if (TYPE_PTR_P (intype)
5387 && (complain & tf_warning)
5388 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5389 COMPARE_BASE | COMPARE_DERIVED)))
5390 warning (0, "casting %qT to %qT does not dereference pointer",
5393 expr = cp_build_unary_op (ADDR_EXPR, expr, 0, complain);
5394 if (expr != error_mark_node)
5395 expr = build_reinterpret_cast_1
5396 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5398 if (expr != error_mark_node)
5399 expr = cp_build_indirect_ref (expr, 0, complain);
5403 /* As a G++ extension, we consider conversions from member
5404 functions, and pointers to member functions to
5405 pointer-to-function and pointer-to-void types. If
5406 -Wno-pmf-conversions has not been specified,
5407 convert_member_func_to_ptr will issue an error message. */
5408 if ((TYPE_PTRMEMFUNC_P (intype)
5409 || TREE_CODE (intype) == METHOD_TYPE)
5410 && TYPE_PTR_P (type)
5411 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5412 || VOID_TYPE_P (TREE_TYPE (type))))
5413 return convert_member_func_to_ptr (type, expr);
5415 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5416 array-to-pointer, and function-to-pointer conversions are
5418 expr = decay_conversion (expr);
5420 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5421 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5422 if (TREE_CODE (expr) == NOP_EXPR
5423 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5424 expr = TREE_OPERAND (expr, 0);
5426 if (error_operand_p (expr))
5427 return error_mark_node;
5429 intype = TREE_TYPE (expr);
5431 /* [expr.reinterpret.cast]
5432 A pointer can be converted to any integral type large enough to
5434 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5436 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5438 if (complain & tf_error)
5439 permerror (input_location, "cast from %qT to %qT loses precision",
5442 return error_mark_node;
5445 /* [expr.reinterpret.cast]
5446 A value of integral or enumeration type can be explicitly
5447 converted to a pointer. */
5448 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5451 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5452 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5453 return fold_if_not_in_template (build_nop (type, expr));
5454 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5455 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5460 check_for_casting_away_constness (intype, type, REINTERPRET_CAST_EXPR);
5461 /* Warn about possible alignment problems. */
5462 if (STRICT_ALIGNMENT && warn_cast_align
5463 && (complain & tf_warning)
5464 && !VOID_TYPE_P (type)
5465 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5466 && COMPLETE_TYPE_P (TREE_TYPE (type))
5467 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5468 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5469 warning (OPT_Wcast_align, "cast from %qT to %qT "
5470 "increases required alignment of target type", intype, type);
5472 /* We need to strip nops here, because the front end likes to
5473 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5475 if (warn_strict_aliasing <= 2)
5476 strict_aliasing_warning (intype, type, sexpr);
5478 return fold_if_not_in_template (build_nop (type, expr));
5480 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5481 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5483 if (pedantic && (complain & tf_warning))
5484 /* Only issue a warning, as we have always supported this
5485 where possible, and it is necessary in some cases. DR 195
5486 addresses this issue, but as of 2004/10/26 is still in
5488 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5489 return fold_if_not_in_template (build_nop (type, expr));
5491 else if (TREE_CODE (type) == VECTOR_TYPE)
5492 return fold_if_not_in_template (convert_to_vector (type, expr));
5493 else if (TREE_CODE (intype) == VECTOR_TYPE && INTEGRAL_TYPE_P (type))
5494 return fold_if_not_in_template (convert_to_integer (type, expr));
5499 if (complain & tf_error)
5500 error ("invalid cast from type %qT to type %qT", intype, type);
5501 return error_mark_node;
5504 return cp_convert (type, expr);
5508 build_reinterpret_cast (tree type, tree expr, tsubst_flags_t complain)
5510 if (type == error_mark_node || expr == error_mark_node)
5511 return error_mark_node;
5513 if (processing_template_decl)
5515 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5517 if (!TREE_SIDE_EFFECTS (t)
5518 && type_dependent_expression_p (expr))
5519 /* There might turn out to be side effects inside expr. */
5520 TREE_SIDE_EFFECTS (t) = 1;
5521 return convert_from_reference (t);
5524 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5525 /*valid_p=*/NULL, complain);
5528 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5529 return an appropriate expression. Otherwise, return
5530 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5531 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5532 performing a C-style cast, its value upon return will indicate
5533 whether or not the conversion succeeded. */
5536 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5540 tree reference_type;
5542 /* Callers are responsible for handling error_mark_node as a
5543 destination type. */
5544 gcc_assert (dst_type != error_mark_node);
5545 /* In a template, callers should be building syntactic
5546 representations of casts, not using this machinery. */
5547 gcc_assert (!processing_template_decl);
5549 /* Assume the conversion is invalid. */
5553 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5556 error ("invalid use of const_cast with type %qT, "
5557 "which is not a pointer, "
5558 "reference, nor a pointer-to-data-member type", dst_type);
5559 return error_mark_node;
5562 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5565 error ("invalid use of const_cast with type %qT, which is a pointer "
5566 "or reference to a function type", dst_type);
5567 return error_mark_node;
5570 /* Save casted types in the function's used types hash table. */
5571 used_types_insert (dst_type);
5573 src_type = TREE_TYPE (expr);
5574 /* Expressions do not really have reference types. */
5575 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5576 src_type = TREE_TYPE (src_type);
5578 /* [expr.const.cast]
5580 An lvalue of type T1 can be explicitly converted to an lvalue of
5581 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5582 types) if a pointer to T1 can be explicitly converted to the type
5583 pointer to T2 using a const_cast. */
5584 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5586 reference_type = dst_type;
5587 if (! real_lvalue_p (expr))
5590 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5591 src_type, dst_type);
5592 return error_mark_node;
5594 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5595 src_type = build_pointer_type (src_type);
5599 reference_type = NULL_TREE;
5600 /* If the destination type is not a reference type, the
5601 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5602 conversions are performed. */
5603 src_type = type_decays_to (src_type);
5604 if (src_type == error_mark_node)
5605 return error_mark_node;
5608 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5609 && comp_ptr_ttypes_const (dst_type, src_type))
5614 /* This cast is actually a C-style cast. Issue a warning if
5615 the user is making a potentially unsafe cast. */
5616 check_for_casting_away_constness (src_type, dst_type, CAST_EXPR);
5620 expr = cp_build_unary_op (ADDR_EXPR, expr, 0,
5621 complain? tf_warning_or_error : tf_none);
5622 expr = build_nop (reference_type, expr);
5623 return convert_from_reference (expr);
5627 expr = decay_conversion (expr);
5628 /* build_c_cast puts on a NOP_EXPR to make the result not an
5629 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5630 non-lvalue context. */
5631 if (TREE_CODE (expr) == NOP_EXPR
5632 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5633 expr = TREE_OPERAND (expr, 0);
5634 return build_nop (dst_type, expr);
5639 error ("invalid const_cast from type %qT to type %qT",
5640 src_type, dst_type);
5641 return error_mark_node;
5645 build_const_cast (tree type, tree expr, tsubst_flags_t complain)
5647 if (type == error_mark_node || error_operand_p (expr))
5648 return error_mark_node;
5650 if (processing_template_decl)
5652 tree t = build_min (CONST_CAST_EXPR, type, expr);
5654 if (!TREE_SIDE_EFFECTS (t)
5655 && type_dependent_expression_p (expr))
5656 /* There might turn out to be side effects inside expr. */
5657 TREE_SIDE_EFFECTS (t) = 1;
5658 return convert_from_reference (t);
5661 return build_const_cast_1 (type, expr, complain & tf_error,
5665 /* Like cp_build_c_cast, but for the c-common bits. */
5668 build_c_cast (tree type, tree expr)
5670 return cp_build_c_cast (type, expr, tf_warning_or_error);
5673 /* Build an expression representing an explicit C-style cast to type
5674 TYPE of expression EXPR. */
5677 cp_build_c_cast (tree type, tree expr, tsubst_flags_t complain)
5683 if (type == error_mark_node || error_operand_p (expr))
5684 return error_mark_node;
5686 if (processing_template_decl)
5688 tree t = build_min (CAST_EXPR, type,
5689 tree_cons (NULL_TREE, value, NULL_TREE));
5690 /* We don't know if it will or will not have side effects. */
5691 TREE_SIDE_EFFECTS (t) = 1;
5692 return convert_from_reference (t);
5695 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5696 'Class') should always be retained, because this information aids
5697 in method lookup. */
5698 if (objc_is_object_ptr (type)
5699 && objc_is_object_ptr (TREE_TYPE (expr)))
5700 return build_nop (type, expr);
5702 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5703 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5704 if (TREE_CODE (type) != REFERENCE_TYPE
5705 && TREE_CODE (value) == NOP_EXPR
5706 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5707 value = TREE_OPERAND (value, 0);
5709 if (TREE_CODE (type) == ARRAY_TYPE)
5711 /* Allow casting from T1* to T2[] because Cfront allows it.
5712 NIHCL uses it. It is not valid ISO C++ however. */
5713 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5715 if (complain & tf_error)
5716 permerror (input_location, "ISO C++ forbids casting to an array type %qT", type);
5718 return error_mark_node;
5719 type = build_pointer_type (TREE_TYPE (type));
5723 if (complain & tf_error)
5724 error ("ISO C++ forbids casting to an array type %qT", type);
5725 return error_mark_node;
5729 if (TREE_CODE (type) == FUNCTION_TYPE
5730 || TREE_CODE (type) == METHOD_TYPE)
5732 if (complain & tf_error)
5733 error ("invalid cast to function type %qT", type);
5734 return error_mark_node;
5737 /* A C-style cast can be a const_cast. */
5738 result = build_const_cast_1 (type, value, /*complain=*/false,
5743 /* Or a static cast. */
5744 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5745 &valid_p, complain);
5746 /* Or a reinterpret_cast. */
5748 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5749 &valid_p, complain);
5750 /* The static_cast or reinterpret_cast may be followed by a
5753 /* A valid cast may result in errors if, for example, a
5754 conversion to am ambiguous base class is required. */
5755 && !error_operand_p (result))
5759 /* Non-class rvalues always have cv-unqualified type. */
5760 if (!CLASS_TYPE_P (type))
5761 type = TYPE_MAIN_VARIANT (type);
5762 result_type = TREE_TYPE (result);
5763 if (!CLASS_TYPE_P (result_type))
5764 result_type = TYPE_MAIN_VARIANT (result_type);
5765 /* If the type of RESULT does not match TYPE, perform a
5766 const_cast to make it match. If the static_cast or
5767 reinterpret_cast succeeded, we will differ by at most
5768 cv-qualification, so the follow-on const_cast is guaranteed
5770 if (!same_type_p (non_reference (type), non_reference (result_type)))
5772 result = build_const_cast_1 (type, result, false, &valid_p);
5773 gcc_assert (valid_p);
5778 return error_mark_node;
5781 /* For use from the C common bits. */
5783 build_modify_expr (location_t location ATTRIBUTE_UNUSED,
5784 tree lhs, enum tree_code modifycode, tree rhs)
5786 return cp_build_modify_expr (lhs, modifycode, rhs, tf_warning_or_error);
5789 /* Build an assignment expression of lvalue LHS from value RHS.
5790 MODIFYCODE is the code for a binary operator that we use
5791 to combine the old value of LHS with RHS to get the new value.
5792 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5794 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5797 cp_build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
5798 tsubst_flags_t complain)
5802 tree lhstype = TREE_TYPE (lhs);
5803 tree olhstype = lhstype;
5804 bool plain_assign = (modifycode == NOP_EXPR);
5806 /* Avoid duplicate error messages from operands that had errors. */
5807 if (error_operand_p (lhs) || error_operand_p (rhs))
5808 return error_mark_node;
5810 /* Handle control structure constructs used as "lvalues". */
5811 switch (TREE_CODE (lhs))
5813 /* Handle --foo = 5; as these are valid constructs in C++. */
5814 case PREDECREMENT_EXPR:
5815 case PREINCREMENT_EXPR:
5816 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5817 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5818 stabilize_reference (TREE_OPERAND (lhs, 0)),
5819 TREE_OPERAND (lhs, 1));
5820 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0),
5821 modifycode, rhs, complain);
5822 if (newrhs == error_mark_node)
5823 return error_mark_node;
5824 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5826 /* Handle (a, b) used as an "lvalue". */
5828 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 1),
5829 modifycode, rhs, complain);
5830 if (newrhs == error_mark_node)
5831 return error_mark_node;
5832 return build2 (COMPOUND_EXPR, lhstype,
5833 TREE_OPERAND (lhs, 0), newrhs);
5836 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5837 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5838 stabilize_reference (TREE_OPERAND (lhs, 0)),
5839 TREE_OPERAND (lhs, 1));
5840 newrhs = cp_build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs,
5842 if (newrhs == error_mark_node)
5843 return error_mark_node;
5844 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5848 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
5849 when neither operand has side-effects. */
5850 if (!lvalue_or_else (lhs, lv_assign, complain))
5851 return error_mark_node;
5853 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
5854 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
5856 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
5857 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
5859 TREE_OPERAND (lhs, 0),
5860 TREE_OPERAND (lhs, 1)),
5861 TREE_OPERAND (lhs, 0),
5862 TREE_OPERAND (lhs, 1));
5865 /* Handle (a ? b : c) used as an "lvalue". */
5868 /* Produce (a ? (b = rhs) : (c = rhs))
5869 except that the RHS goes through a save-expr
5870 so the code to compute it is only emitted once. */
5872 tree preeval = NULL_TREE;
5874 if (VOID_TYPE_P (TREE_TYPE (rhs)))
5876 if (complain & tf_error)
5877 error ("void value not ignored as it ought to be");
5878 return error_mark_node;
5881 rhs = stabilize_expr (rhs, &preeval);
5883 /* Check this here to avoid odd errors when trying to convert
5884 a throw to the type of the COND_EXPR. */
5885 if (!lvalue_or_else (lhs, lv_assign, complain))
5886 return error_mark_node;
5888 cond = build_conditional_expr
5889 (TREE_OPERAND (lhs, 0),
5890 cp_build_modify_expr (TREE_OPERAND (lhs, 1),
5891 modifycode, rhs, complain),
5892 cp_build_modify_expr (TREE_OPERAND (lhs, 2),
5893 modifycode, rhs, complain),
5896 if (cond == error_mark_node)
5898 /* Make sure the code to compute the rhs comes out
5899 before the split. */
5901 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5909 if (modifycode == INIT_EXPR)
5911 if (TREE_CODE (rhs) == CONSTRUCTOR)
5913 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5914 /* Call convert to generate an error; see PR 11063. */
5915 rhs = convert (lhstype, rhs);
5916 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
5917 TREE_SIDE_EFFECTS (result) = 1;
5920 else if (! MAYBE_CLASS_TYPE_P (lhstype))
5921 /* Do the default thing. */;
5924 result = build_special_member_call (lhs, complete_ctor_identifier,
5925 build_tree_list (NULL_TREE, rhs),
5926 lhstype, LOOKUP_NORMAL,
5928 if (result == NULL_TREE)
5929 return error_mark_node;
5935 lhs = require_complete_type (lhs);
5936 if (lhs == error_mark_node)
5937 return error_mark_node;
5939 if (modifycode == NOP_EXPR)
5941 /* `operator=' is not an inheritable operator. */
5942 if (! MAYBE_CLASS_TYPE_P (lhstype))
5943 /* Do the default thing. */;
5946 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5947 lhs, rhs, make_node (NOP_EXPR),
5948 /*overloaded_p=*/NULL,
5950 if (result == NULL_TREE)
5951 return error_mark_node;
5958 /* A binary op has been requested. Combine the old LHS
5959 value with the RHS producing the value we should actually
5960 store into the LHS. */
5961 gcc_assert (!((TREE_CODE (lhstype) == REFERENCE_TYPE
5962 && MAYBE_CLASS_TYPE_P (TREE_TYPE (lhstype)))
5963 || MAYBE_CLASS_TYPE_P (lhstype)));
5965 lhs = stabilize_reference (lhs);
5966 newrhs = cp_build_binary_op (input_location,
5967 modifycode, lhs, rhs,
5969 if (newrhs == error_mark_node)
5971 if (complain & tf_error)
5972 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
5973 TREE_TYPE (lhs), TREE_TYPE (rhs));
5974 return error_mark_node;
5977 /* Now it looks like a plain assignment. */
5978 modifycode = NOP_EXPR;
5980 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
5981 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
5984 /* The left-hand side must be an lvalue. */
5985 if (!lvalue_or_else (lhs, lv_assign, complain))
5986 return error_mark_node;
5988 /* Warn about modifying something that is `const'. Don't warn if
5989 this is initialization. */
5990 if (modifycode != INIT_EXPR
5991 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5992 /* Functions are not modifiable, even though they are
5994 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5995 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5996 /* If it's an aggregate and any field is const, then it is
5997 effectively const. */
5998 || (CLASS_TYPE_P (lhstype)
5999 && C_TYPE_FIELDS_READONLY (lhstype))))
6001 if (complain & tf_error)
6002 readonly_error (lhs, "assignment");
6004 return error_mark_node;
6007 /* If storing into a structure or union member, it may have been given a
6008 lowered bitfield type. We need to convert to the declared type first,
6009 so retrieve it now. */
6011 olhstype = unlowered_expr_type (lhs);
6013 /* Convert new value to destination type. */
6015 if (TREE_CODE (lhstype) == ARRAY_TYPE)
6019 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
6020 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
6022 if (complain & tf_error)
6023 error ("incompatible types in assignment of %qT to %qT",
6024 TREE_TYPE (rhs), lhstype);
6025 return error_mark_node;
6028 /* Allow array assignment in compiler-generated code. */
6029 if (!current_function_decl || !DECL_ARTIFICIAL (current_function_decl))
6031 /* This routine is used for both initialization and assignment.
6032 Make sure the diagnostic message differentiates the context. */
6033 if (complain & tf_error)
6035 if (modifycode == INIT_EXPR)
6036 error ("array used as initializer");
6038 error ("invalid array assignment");
6040 return error_mark_node;
6043 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
6044 ? 1 + (modifycode != INIT_EXPR): 0;
6045 return build_vec_init (lhs, NULL_TREE, newrhs,
6046 /*explicit_value_init_p=*/false,
6047 from_array, complain);
6050 if (modifycode == INIT_EXPR)
6051 newrhs = convert_for_initialization (lhs, olhstype, newrhs, LOOKUP_NORMAL,
6052 "initialization", NULL_TREE, 0,
6055 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
6056 NULL_TREE, 0, complain);
6058 if (!same_type_p (lhstype, olhstype))
6059 newrhs = cp_convert_and_check (lhstype, newrhs);
6061 if (modifycode != INIT_EXPR)
6063 if (TREE_CODE (newrhs) == CALL_EXPR
6064 && TYPE_NEEDS_CONSTRUCTING (lhstype))
6065 newrhs = build_cplus_new (lhstype, newrhs);
6067 /* Can't initialize directly from a TARGET_EXPR, since that would
6068 cause the lhs to be constructed twice, and possibly result in
6069 accidental self-initialization. So we force the TARGET_EXPR to be
6070 expanded without a target. */
6071 if (TREE_CODE (newrhs) == TARGET_EXPR)
6072 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
6073 TREE_OPERAND (newrhs, 0));
6076 if (newrhs == error_mark_node)
6077 return error_mark_node;
6079 if (c_dialect_objc () && flag_objc_gc)
6081 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
6087 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
6088 lhstype, lhs, newrhs);
6090 TREE_SIDE_EFFECTS (result) = 1;
6092 TREE_NO_WARNING (result) = 1;
6098 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs,
6099 tsubst_flags_t complain)
6101 if (processing_template_decl)
6102 return build_min_nt (MODOP_EXPR, lhs,
6103 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
6105 if (modifycode != NOP_EXPR)
6107 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
6108 make_node (modifycode),
6109 /*overloaded_p=*/NULL,
6113 TREE_NO_WARNING (rval) = 1;
6117 return cp_build_modify_expr (lhs, modifycode, rhs, complain);
6120 /* Helper function for get_delta_difference which assumes FROM is a base
6121 class of TO. Returns a delta for the conversion of pointer-to-member
6122 of FROM to pointer-to-member of TO. If the conversion is invalid,
6123 returns zero. If FROM is not a base class of TO, returns NULL_TREE.
6124 If C_CAST_P is true, this conversion is taking place as part of a C-style
6128 get_delta_difference_1 (tree from, tree to, bool c_cast_p)
6133 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
6134 if (kind == bk_inaccessible || kind == bk_ambig)
6136 error (" in pointer to member function conversion");
6137 return size_zero_node;
6141 if (kind != bk_via_virtual)
6142 return BINFO_OFFSET (binfo);
6144 /* FROM is a virtual base class of TO. Issue an error or warning
6145 depending on whether or not this is a reinterpret cast. */
6147 error ("pointer to member conversion via virtual base %qT",
6148 BINFO_TYPE (binfo_from_vbase (binfo)));
6150 return size_zero_node;
6157 /* Get difference in deltas for different pointer to member function
6158 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
6159 the conversion is invalid, the constant is zero. If
6160 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
6161 If C_CAST_P is true this conversion is taking place as part of a
6164 Note that the naming of FROM and TO is kind of backwards; the return
6165 value is what we add to a TO in order to get a FROM. They are named
6166 this way because we call this function to find out how to convert from
6167 a pointer to member of FROM to a pointer to member of TO. */
6170 get_delta_difference (tree from, tree to,
6171 bool allow_inverse_p,
6176 if (same_type_ignoring_top_level_qualifiers_p (from, to))
6177 /* Pointer to member of incomplete class is permitted*/
6178 result = size_zero_node;
6180 result = get_delta_difference_1 (from, to, c_cast_p);
6184 if (!allow_inverse_p)
6186 error_not_base_type (from, to);
6187 error (" in pointer to member conversion");
6188 result = size_zero_node;
6192 result = get_delta_difference_1 (to, from, c_cast_p);
6195 result = size_diffop (size_zero_node, result);
6198 error_not_base_type (from, to);
6199 error (" in pointer to member conversion");
6200 result = size_zero_node;
6205 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
6209 /* Return a constructor for the pointer-to-member-function TYPE using
6210 the other components as specified. */
6213 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
6218 VEC(constructor_elt, gc) *v;
6220 /* Pull the FIELD_DECLs out of the type. */
6221 pfn_field = TYPE_FIELDS (type);
6222 delta_field = TREE_CHAIN (pfn_field);
6224 /* Make sure DELTA has the type we want. */
6225 delta = convert_and_check (delta_type_node, delta);
6227 /* Convert to the correct target type if necessary. */
6228 pfn = fold_convert (TREE_TYPE (pfn_field), pfn);
6230 /* Finish creating the initializer. */
6231 v = VEC_alloc(constructor_elt, gc, 2);
6232 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
6233 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
6234 u = build_constructor (type, v);
6235 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
6236 TREE_STATIC (u) = (TREE_CONSTANT (u)
6237 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
6239 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
6244 /* Build a constructor for a pointer to member function. It can be
6245 used to initialize global variables, local variable, or used
6246 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
6249 If FORCE is nonzero, then force this conversion, even if
6250 we would rather not do it. Usually set when using an explicit
6251 cast. A C-style cast is being processed iff C_CAST_P is true.
6253 Return error_mark_node, if something goes wrong. */
6256 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
6262 if (error_operand_p (pfn))
6263 return error_mark_node;
6265 pfn_type = TREE_TYPE (pfn);
6266 to_type = build_ptrmemfunc_type (type);
6268 /* Handle multiple conversions of pointer to member functions. */
6269 if (TYPE_PTRMEMFUNC_P (pfn_type))
6271 tree delta = NULL_TREE;
6272 tree npfn = NULL_TREE;
6276 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
6277 error ("invalid conversion to type %qT from type %qT",
6280 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
6281 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
6285 /* We don't have to do any conversion to convert a
6286 pointer-to-member to its own type. But, we don't want to
6287 just return a PTRMEM_CST if there's an explicit cast; that
6288 cast should make the expression an invalid template argument. */
6289 if (TREE_CODE (pfn) != PTRMEM_CST)
6291 if (same_type_p (to_type, pfn_type))
6293 else if (integer_zerop (n))
6294 return build_reinterpret_cast (to_type, pfn,
6295 tf_warning_or_error);
6298 if (TREE_SIDE_EFFECTS (pfn))
6299 pfn = save_expr (pfn);
6301 /* Obtain the function pointer and the current DELTA. */
6302 if (TREE_CODE (pfn) == PTRMEM_CST)
6303 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
6306 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
6307 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
6310 /* Just adjust the DELTA field. */
6311 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6312 (TREE_TYPE (delta), ptrdiff_type_node));
6313 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
6314 n = cp_build_binary_op (input_location,
6315 LSHIFT_EXPR, n, integer_one_node,
6316 tf_warning_or_error);
6317 delta = cp_build_binary_op (input_location,
6318 PLUS_EXPR, delta, n, tf_warning_or_error);
6319 return build_ptrmemfunc1 (to_type, delta, npfn);
6322 /* Handle null pointer to member function conversions. */
6323 if (integer_zerop (pfn))
6325 pfn = build_c_cast (type, integer_zero_node);
6326 return build_ptrmemfunc1 (to_type,
6331 if (type_unknown_p (pfn))
6332 return instantiate_type (type, pfn, tf_warning_or_error);
6334 fn = TREE_OPERAND (pfn, 0);
6335 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
6336 /* In a template, we will have preserved the
6338 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
6339 return make_ptrmem_cst (to_type, fn);
6342 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
6345 ??? There is no consistency as to the types returned for the above
6346 values. Some code acts as if it were a sizetype and some as if it were
6347 integer_type_node. */
6350 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
6352 tree type = TREE_TYPE (cst);
6353 tree fn = PTRMEM_CST_MEMBER (cst);
6354 tree ptr_class, fn_class;
6356 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6358 /* The class that the function belongs to. */
6359 fn_class = DECL_CONTEXT (fn);
6361 /* The class that we're creating a pointer to member of. */
6362 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
6364 /* First, calculate the adjustment to the function's class. */
6365 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
6368 if (!DECL_VIRTUAL_P (fn))
6369 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
6372 /* If we're dealing with a virtual function, we have to adjust 'this'
6373 again, to point to the base which provides the vtable entry for
6374 fn; the call will do the opposite adjustment. */
6375 tree orig_class = DECL_CONTEXT (fn);
6376 tree binfo = binfo_or_else (orig_class, fn_class);
6377 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6378 *delta, BINFO_OFFSET (binfo));
6379 *delta = fold_if_not_in_template (*delta);
6381 /* We set PFN to the vtable offset at which the function can be
6382 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6383 case delta is shifted left, and then incremented). */
6384 *pfn = DECL_VINDEX (fn);
6385 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
6386 TYPE_SIZE_UNIT (vtable_entry_type));
6387 *pfn = fold_if_not_in_template (*pfn);
6389 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
6391 case ptrmemfunc_vbit_in_pfn:
6392 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6394 *pfn = fold_if_not_in_template (*pfn);
6397 case ptrmemfunc_vbit_in_delta:
6398 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6399 *delta, integer_one_node);
6400 *delta = fold_if_not_in_template (*delta);
6401 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6402 *delta, integer_one_node);
6403 *delta = fold_if_not_in_template (*delta);
6410 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6411 *pfn = fold_if_not_in_template (*pfn);
6415 /* Return an expression for PFN from the pointer-to-member function
6419 pfn_from_ptrmemfunc (tree t)
6421 if (TREE_CODE (t) == PTRMEM_CST)
6426 expand_ptrmemfunc_cst (t, &delta, &pfn);
6431 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6434 /* Return an expression for DELTA from the pointer-to-member function
6438 delta_from_ptrmemfunc (tree t)
6440 if (TREE_CODE (t) == PTRMEM_CST)
6445 expand_ptrmemfunc_cst (t, &delta, &pfn);
6450 return build_ptrmemfunc_access_expr (t, delta_identifier);
6453 /* Convert value RHS to type TYPE as preparation for an assignment to
6454 an lvalue of type TYPE. ERRTYPE is a string to use in error
6455 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6456 are doing the conversion in order to pass the PARMNUMth argument of
6460 convert_for_assignment (tree type, tree rhs,
6461 const char *errtype, tree fndecl, int parmnum,
6462 tsubst_flags_t complain)
6465 enum tree_code coder;
6467 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6468 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6469 rhs = TREE_OPERAND (rhs, 0);
6471 rhstype = TREE_TYPE (rhs);
6472 coder = TREE_CODE (rhstype);
6474 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6475 && vector_types_convertible_p (type, rhstype, true))
6476 return convert (type, rhs);
6478 if (rhs == error_mark_node || rhstype == error_mark_node)
6479 return error_mark_node;
6480 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6481 return error_mark_node;
6483 /* The RHS of an assignment cannot have void type. */
6484 if (coder == VOID_TYPE)
6486 if (complain & tf_error)
6487 error ("void value not ignored as it ought to be");
6488 return error_mark_node;
6491 /* Simplify the RHS if possible. */
6492 if (TREE_CODE (rhs) == CONST_DECL)
6493 rhs = DECL_INITIAL (rhs);
6495 if (c_dialect_objc ())
6498 tree rname = fndecl;
6500 if (!strcmp (errtype, "assignment"))
6502 else if (!strcmp (errtype, "initialization"))
6506 tree selector = objc_message_selector ();
6510 if (selector && parmno > 1)
6517 if (objc_compare_types (type, rhstype, parmno, rname))
6518 return convert (type, rhs);
6523 The expression is implicitly converted (clause _conv_) to the
6524 cv-unqualified type of the left operand.
6526 We allow bad conversions here because by the time we get to this point
6527 we are committed to doing the conversion. If we end up doing a bad
6528 conversion, convert_like will complain. */
6529 if (!can_convert_arg_bad (type, rhstype, rhs))
6531 /* When -Wno-pmf-conversions is use, we just silently allow
6532 conversions from pointers-to-members to plain pointers. If
6533 the conversion doesn't work, cp_convert will complain. */
6535 && TYPE_PTR_P (type)
6536 && TYPE_PTRMEMFUNC_P (rhstype))
6537 rhs = cp_convert (strip_top_quals (type), rhs);
6540 if (complain & tf_error)
6542 /* If the right-hand side has unknown type, then it is an
6543 overloaded function. Call instantiate_type to get error
6545 if (rhstype == unknown_type_node)
6546 instantiate_type (type, rhs, tf_warning_or_error);
6548 error ("cannot convert %qT to %qT for argument %qP to %qD",
6549 rhstype, type, parmnum, fndecl);
6551 error ("cannot convert %qT to %qT in %s", rhstype, type,
6554 return error_mark_node;
6557 if (warn_missing_format_attribute)
6559 const enum tree_code codel = TREE_CODE (type);
6560 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6562 && check_missing_format_attribute (type, rhstype)
6563 && (complain & tf_warning))
6564 warning (OPT_Wmissing_format_attribute,
6565 "%s might be a candidate for a format attribute",
6569 /* If -Wparentheses, warn about a = b = c when a has type bool and b
6571 if (warn_parentheses
6572 && type == boolean_type_node
6573 && TREE_CODE (rhs) == MODIFY_EXPR
6574 && !TREE_NO_WARNING (rhs)
6575 && TREE_TYPE (rhs) != boolean_type_node
6576 && (complain & tf_warning))
6578 warning (OPT_Wparentheses,
6579 "suggest parentheses around assignment used as truth value");
6580 TREE_NO_WARNING (rhs) = 1;
6583 return perform_implicit_conversion (strip_top_quals (type), rhs, complain);
6586 /* Convert RHS to be of type TYPE.
6587 If EXP is nonzero, it is the target of the initialization.
6588 ERRTYPE is a string to use in error messages.
6590 Two major differences between the behavior of
6591 `convert_for_assignment' and `convert_for_initialization'
6592 are that references are bashed in the former, while
6593 copied in the latter, and aggregates are assigned in
6594 the former (operator=) while initialized in the
6597 If using constructor make sure no conversion operator exists, if one does
6598 exist, an ambiguity exists.
6600 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6603 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6604 const char *errtype, tree fndecl, int parmnum,
6605 tsubst_flags_t complain)
6607 enum tree_code codel = TREE_CODE (type);
6609 enum tree_code coder;
6611 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6612 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6613 if (TREE_CODE (rhs) == NOP_EXPR
6614 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6615 && codel != REFERENCE_TYPE)
6616 rhs = TREE_OPERAND (rhs, 0);
6618 if (type == error_mark_node
6619 || rhs == error_mark_node
6620 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6621 return error_mark_node;
6623 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6624 && TREE_CODE (type) != ARRAY_TYPE
6625 && (TREE_CODE (type) != REFERENCE_TYPE
6626 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6627 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6628 && (TREE_CODE (type) != REFERENCE_TYPE
6629 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6630 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6631 rhs = decay_conversion (rhs);
6633 rhstype = TREE_TYPE (rhs);
6634 coder = TREE_CODE (rhstype);
6636 if (coder == ERROR_MARK)
6637 return error_mark_node;
6639 /* We accept references to incomplete types, so we can
6640 return here before checking if RHS is of complete type. */
6642 if (codel == REFERENCE_TYPE)
6644 /* This should eventually happen in convert_arguments. */
6645 int savew = 0, savee = 0;
6648 savew = warningcount, savee = errorcount;
6649 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6653 if (warningcount > savew)
6654 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6655 else if (errorcount > savee)
6656 error ("in passing argument %P of %q+D", parmnum, fndecl);
6662 exp = require_complete_type (exp);
6663 if (exp == error_mark_node)
6664 return error_mark_node;
6666 rhstype = non_reference (rhstype);
6668 type = complete_type (type);
6670 if (MAYBE_CLASS_TYPE_P (type))
6671 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6673 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum,
6677 /* If RETVAL is the address of, or a reference to, a local variable or
6678 temporary give an appropriate warning. */
6681 maybe_warn_about_returning_address_of_local (tree retval)
6683 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6684 tree whats_returned = retval;
6688 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6689 whats_returned = TREE_OPERAND (whats_returned, 1);
6690 else if (CONVERT_EXPR_P (whats_returned)
6691 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR)
6692 whats_returned = TREE_OPERAND (whats_returned, 0);
6697 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6699 whats_returned = TREE_OPERAND (whats_returned, 0);
6701 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6703 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6704 || TREE_CODE (whats_returned) == TARGET_EXPR)
6706 warning (0, "returning reference to temporary");
6709 if (TREE_CODE (whats_returned) == VAR_DECL
6710 && DECL_NAME (whats_returned)
6711 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6713 warning (0, "reference to non-lvalue returned");
6718 while (TREE_CODE (whats_returned) == COMPONENT_REF
6719 || TREE_CODE (whats_returned) == ARRAY_REF)
6720 whats_returned = TREE_OPERAND (whats_returned, 0);
6722 if (DECL_P (whats_returned)
6723 && DECL_NAME (whats_returned)
6724 && DECL_FUNCTION_SCOPE_P (whats_returned)
6725 && !(TREE_STATIC (whats_returned)
6726 || TREE_PUBLIC (whats_returned)))
6728 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6729 warning (0, "reference to local variable %q+D returned",
6732 warning (0, "address of local variable %q+D returned",
6738 /* Check that returning RETVAL from the current function is valid.
6739 Return an expression explicitly showing all conversions required to
6740 change RETVAL into the function return type, and to assign it to
6741 the DECL_RESULT for the function. Set *NO_WARNING to true if
6742 code reaches end of non-void function warning shouldn't be issued
6743 on this RETURN_EXPR. */
6746 check_return_expr (tree retval, bool *no_warning)
6749 /* The type actually returned by the function, after any
6752 int fn_returns_value_p;
6753 bool named_return_value_okay_p;
6755 *no_warning = false;
6757 /* A `volatile' function is one that isn't supposed to return, ever.
6758 (This is a G++ extension, used to get better code for functions
6759 that call the `volatile' function.) */
6760 if (TREE_THIS_VOLATILE (current_function_decl))
6761 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6763 /* Check for various simple errors. */
6764 if (DECL_DESTRUCTOR_P (current_function_decl))
6767 error ("returning a value from a destructor");
6770 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6772 if (in_function_try_handler)
6773 /* If a return statement appears in a handler of the
6774 function-try-block of a constructor, the program is ill-formed. */
6775 error ("cannot return from a handler of a function-try-block of a constructor");
6777 /* You can't return a value from a constructor. */
6778 error ("returning a value from a constructor");
6782 if (processing_template_decl)
6784 current_function_returns_value = 1;
6785 if (check_for_bare_parameter_packs (retval))
6786 retval = error_mark_node;
6790 /* When no explicit return-value is given in a function with a named
6791 return value, the named return value is used. */
6792 result = DECL_RESULT (current_function_decl);
6793 valtype = TREE_TYPE (result);
6794 gcc_assert (valtype != NULL_TREE);
6795 fn_returns_value_p = !VOID_TYPE_P (valtype);
6796 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6799 /* Check for a return statement with no return value in a function
6800 that's supposed to return a value. */
6801 if (!retval && fn_returns_value_p)
6803 permerror (input_location, "return-statement with no value, in function returning %qT",
6805 /* Clear this, so finish_function won't say that we reach the
6806 end of a non-void function (which we don't, we gave a
6808 current_function_returns_null = 0;
6809 /* And signal caller that TREE_NO_WARNING should be set on the
6810 RETURN_EXPR to avoid control reaches end of non-void function
6811 warnings in tree-cfg.c. */
6814 /* Check for a return statement with a value in a function that
6815 isn't supposed to return a value. */
6816 else if (retval && !fn_returns_value_p)
6818 if (VOID_TYPE_P (TREE_TYPE (retval)))
6819 /* You can return a `void' value from a function of `void'
6820 type. In that case, we have to evaluate the expression for
6821 its side-effects. */
6822 finish_expr_stmt (retval);
6824 permerror (input_location, "return-statement with a value, in function "
6825 "returning 'void'");
6826 current_function_returns_null = 1;
6828 /* There's really no value to return, after all. */
6832 /* Remember that this function can sometimes return without a
6834 current_function_returns_null = 1;
6836 /* Remember that this function did return a value. */
6837 current_function_returns_value = 1;
6839 /* Check for erroneous operands -- but after giving ourselves a
6840 chance to provide an error about returning a value from a void
6842 if (error_operand_p (retval))
6844 current_function_return_value = error_mark_node;
6845 return error_mark_node;
6848 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
6849 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
6850 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
6851 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
6853 && retval && null_ptr_cst_p (retval))
6854 warning (0, "%<operator new%> must not return NULL unless it is "
6855 "declared %<throw()%> (or -fcheck-new is in effect)");
6857 /* Effective C++ rule 15. See also start_function. */
6859 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
6863 /* The function return type must be a reference to the current
6865 if (TREE_CODE (valtype) == REFERENCE_TYPE
6866 && same_type_ignoring_top_level_qualifiers_p
6867 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
6869 /* Returning '*this' is obviously OK. */
6870 if (retval == current_class_ref)
6872 /* If we are calling a function whose return type is the same of
6873 the current class reference, it is ok. */
6874 else if (TREE_CODE (retval) == INDIRECT_REF
6875 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
6880 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
6883 /* The fabled Named Return Value optimization, as per [class.copy]/15:
6885 [...] For a function with a class return type, if the expression
6886 in the return statement is the name of a local object, and the cv-
6887 unqualified type of the local object is the same as the function
6888 return type, an implementation is permitted to omit creating the tem-
6889 porary object to hold the function return value [...]
6891 So, if this is a value-returning function that always returns the same
6892 local variable, remember it.
6894 It might be nice to be more flexible, and choose the first suitable
6895 variable even if the function sometimes returns something else, but
6896 then we run the risk of clobbering the variable we chose if the other
6897 returned expression uses the chosen variable somehow. And people expect
6898 this restriction, anyway. (jason 2000-11-19)
6900 See finish_function and finalize_nrv for the rest of this optimization. */
6902 named_return_value_okay_p =
6903 (retval != NULL_TREE
6904 /* Must be a local, automatic variable. */
6905 && TREE_CODE (retval) == VAR_DECL
6906 && DECL_CONTEXT (retval) == current_function_decl
6907 && ! TREE_STATIC (retval)
6908 && ! DECL_ANON_UNION_VAR_P (retval)
6909 && (DECL_ALIGN (retval)
6910 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6911 /* The cv-unqualified type of the returned value must be the
6912 same as the cv-unqualified return type of the
6914 && same_type_p ((TYPE_MAIN_VARIANT (TREE_TYPE (retval))),
6916 (TREE_TYPE (TREE_TYPE (current_function_decl)))))
6917 /* And the returned value must be non-volatile. */
6918 && ! TYPE_VOLATILE (TREE_TYPE (retval)));
6920 if (fn_returns_value_p && flag_elide_constructors)
6922 if (named_return_value_okay_p
6923 && (current_function_return_value == NULL_TREE
6924 || current_function_return_value == retval))
6925 current_function_return_value = retval;
6927 current_function_return_value = error_mark_node;
6930 /* We don't need to do any conversions when there's nothing being
6935 /* Do any required conversions. */
6936 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6937 /* No conversions are required. */
6941 /* The type the function is declared to return. */
6942 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6943 int flags = LOOKUP_NORMAL | LOOKUP_ONLYCONVERTING;
6945 /* The functype's return type will have been set to void, if it
6946 was an incomplete type. Just treat this as 'return;' */
6947 if (VOID_TYPE_P (functype))
6948 return error_mark_node;
6950 /* Under C++0x [12.8/16 class.copy], a returned lvalue is sometimes
6951 treated as an rvalue for the purposes of overload resolution to
6952 favor move constructors over copy constructors. */
6953 if ((cxx_dialect != cxx98)
6954 && named_return_value_okay_p
6955 /* The variable must not have the `volatile' qualifier. */
6956 && !(cp_type_quals (TREE_TYPE (retval)) & TYPE_QUAL_VOLATILE)
6957 /* The return type must be a class type. */
6958 && CLASS_TYPE_P (TREE_TYPE (TREE_TYPE (current_function_decl))))
6959 flags = flags | LOOKUP_PREFER_RVALUE;
6961 /* First convert the value to the function's return type, then
6962 to the type of return value's location to handle the
6963 case that functype is smaller than the valtype. */
6964 retval = convert_for_initialization
6965 (NULL_TREE, functype, retval, flags, "return", NULL_TREE, 0,
6966 tf_warning_or_error);
6967 retval = convert (valtype, retval);
6969 /* If the conversion failed, treat this just like `return;'. */
6970 if (retval == error_mark_node)
6972 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6973 else if (! cfun->returns_struct
6974 && TREE_CODE (retval) == TARGET_EXPR
6975 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6976 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6977 TREE_OPERAND (retval, 0));
6979 maybe_warn_about_returning_address_of_local (retval);
6982 /* Actually copy the value returned into the appropriate location. */
6983 if (retval && retval != result)
6984 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
6990 /* Returns nonzero if the pointer-type FROM can be converted to the
6991 pointer-type TO via a qualification conversion. If CONSTP is -1,
6992 then we return nonzero if the pointers are similar, and the
6993 cv-qualification signature of FROM is a proper subset of that of TO.
6995 If CONSTP is positive, then all outer pointers have been
6999 comp_ptr_ttypes_real (tree to, tree from, int constp)
7001 bool to_more_cv_qualified = false;
7002 bool is_opaque_pointer = false;
7004 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7006 if (TREE_CODE (to) != TREE_CODE (from))
7009 if (TREE_CODE (from) == OFFSET_TYPE
7010 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
7011 TYPE_OFFSET_BASETYPE (to)))
7014 /* Const and volatile mean something different for function types,
7015 so the usual checks are not appropriate. */
7016 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
7018 /* In Objective-C++, some types may have been 'volatilized' by
7019 the compiler for EH; when comparing them here, the volatile
7020 qualification must be ignored. */
7021 bool objc_quals_match = objc_type_quals_match (to, from);
7023 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
7026 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
7030 to_more_cv_qualified = true;
7034 constp &= TYPE_READONLY (to);
7037 if (TREE_CODE (to) == VECTOR_TYPE)
7038 is_opaque_pointer = vector_targets_convertible_p (to, from);
7040 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
7041 return ((constp >= 0 || to_more_cv_qualified)
7042 && (is_opaque_pointer
7043 || same_type_ignoring_top_level_qualifiers_p (to, from)));
7047 /* When comparing, say, char ** to char const **, this function takes
7048 the 'char *' and 'char const *'. Do not pass non-pointer/reference
7049 types to this function. */
7052 comp_ptr_ttypes (tree to, tree from)
7054 return comp_ptr_ttypes_real (to, from, 1);
7057 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
7058 type or inheritance-related types, regardless of cv-quals. */
7061 ptr_reasonably_similar (const_tree to, const_tree from)
7063 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7065 /* Any target type is similar enough to void. */
7066 if (TREE_CODE (to) == VOID_TYPE
7067 || TREE_CODE (from) == VOID_TYPE)
7070 if (TREE_CODE (to) != TREE_CODE (from))
7073 if (TREE_CODE (from) == OFFSET_TYPE
7074 && comptypes (TYPE_OFFSET_BASETYPE (to),
7075 TYPE_OFFSET_BASETYPE (from),
7076 COMPARE_BASE | COMPARE_DERIVED))
7079 if (TREE_CODE (to) == VECTOR_TYPE
7080 && vector_types_convertible_p (to, from, false))
7083 if (TREE_CODE (to) == INTEGER_TYPE
7084 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
7087 if (TREE_CODE (to) == FUNCTION_TYPE)
7090 if (TREE_CODE (to) != POINTER_TYPE)
7092 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
7093 COMPARE_BASE | COMPARE_DERIVED);
7097 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
7098 pointer-to-member types) are the same, ignoring cv-qualification at
7102 comp_ptr_ttypes_const (tree to, tree from)
7104 bool is_opaque_pointer = false;
7106 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
7108 if (TREE_CODE (to) != TREE_CODE (from))
7111 if (TREE_CODE (from) == OFFSET_TYPE
7112 && same_type_p (TYPE_OFFSET_BASETYPE (from),
7113 TYPE_OFFSET_BASETYPE (to)))
7116 if (TREE_CODE (to) == VECTOR_TYPE)
7117 is_opaque_pointer = vector_targets_convertible_p (to, from);
7119 if (TREE_CODE (to) != POINTER_TYPE)
7120 return (is_opaque_pointer
7121 || same_type_ignoring_top_level_qualifiers_p (to, from));
7125 /* Returns the type qualifiers for this type, including the qualifiers on the
7126 elements for an array type. */
7129 cp_type_quals (const_tree type)
7131 /* This CONST_CAST is okay because strip_array_types returns its
7132 argument unmodified and we assign it to a const_tree. */
7133 type = strip_array_types (CONST_CAST_TREE(type));
7134 if (type == error_mark_node)
7135 return TYPE_UNQUALIFIED;
7136 return TYPE_QUALS (type);
7139 /* Returns nonzero if the TYPE is const from a C++ perspective: look inside
7143 cp_type_readonly (const_tree type)
7145 /* This CONST_CAST is okay because strip_array_types returns its
7146 argument unmodified and we assign it to a const_tree. */
7147 type = strip_array_types (CONST_CAST_TREE(type));
7148 return TYPE_READONLY (type);
7151 /* Returns nonzero if the TYPE contains a mutable member. */
7154 cp_has_mutable_p (const_tree type)
7156 /* This CONST_CAST is okay because strip_array_types returns its
7157 argument unmodified and we assign it to a const_tree. */
7158 type = strip_array_types (CONST_CAST_TREE(type));
7160 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
7163 /* Set TREE_READONLY and TREE_VOLATILE on DECL as indicated by the
7164 TYPE_QUALS. For a VAR_DECL, this may be an optimistic
7165 approximation. In particular, consider:
7168 struct S { int i; };
7169 const S s = { f(); }
7171 Here, we will make "s" as TREE_READONLY (because it is declared
7172 "const") -- only to reverse ourselves upon seeing that the
7173 initializer is non-constant. */
7176 cp_apply_type_quals_to_decl (int type_quals, tree decl)
7178 tree type = TREE_TYPE (decl);
7180 if (type == error_mark_node)
7183 if (TREE_CODE (type) == FUNCTION_TYPE
7184 && type_quals != TYPE_UNQUALIFIED)
7186 /* This was an error in C++98 (cv-qualifiers cannot be added to
7187 a function type), but DR 295 makes the code well-formed by
7188 dropping the extra qualifiers. */
7191 tree bad_type = build_qualified_type (type, type_quals);
7192 pedwarn (input_location, OPT_pedantic,
7193 "ignoring %qV qualifiers added to function type %qT",
7197 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
7201 /* Avoid setting TREE_READONLY incorrectly. */
7202 if (/* If the object has a constructor, the constructor may modify
7204 TYPE_NEEDS_CONSTRUCTING (type)
7205 /* If the type isn't complete, we don't know yet if it will need
7207 || !COMPLETE_TYPE_P (type)
7208 /* If the type has a mutable component, that component might be
7210 || TYPE_HAS_MUTABLE_P (type))
7211 type_quals &= ~TYPE_QUAL_CONST;
7213 c_apply_type_quals_to_decl (type_quals, decl);
7216 /* Subroutine of casts_away_constness. Make T1 and T2 point at
7217 exemplar types such that casting T1 to T2 is casting away constness
7218 if and only if there is no implicit conversion from T1 to T2. */
7221 casts_away_constness_r (tree *t1, tree *t2)
7226 /* [expr.const.cast]
7228 For multi-level pointer to members and multi-level mixed pointers
7229 and pointers to members (conv.qual), the "member" aspect of a
7230 pointer to member level is ignored when determining if a const
7231 cv-qualifier has been cast away. */
7232 /* [expr.const.cast]
7234 For two pointer types:
7236 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
7237 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
7240 casting from X1 to X2 casts away constness if, for a non-pointer
7241 type T there does not exist an implicit conversion (clause
7244 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
7248 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
7249 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
7250 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
7252 *t1 = cp_build_qualified_type (void_type_node,
7253 cp_type_quals (*t1));
7254 *t2 = cp_build_qualified_type (void_type_node,
7255 cp_type_quals (*t2));
7259 quals1 = cp_type_quals (*t1);
7260 quals2 = cp_type_quals (*t2);
7262 if (TYPE_PTRMEM_P (*t1))
7263 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
7265 *t1 = TREE_TYPE (*t1);
7266 if (TYPE_PTRMEM_P (*t2))
7267 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
7269 *t2 = TREE_TYPE (*t2);
7271 casts_away_constness_r (t1, t2);
7272 *t1 = build_pointer_type (*t1);
7273 *t2 = build_pointer_type (*t2);
7274 *t1 = cp_build_qualified_type (*t1, quals1);
7275 *t2 = cp_build_qualified_type (*t2, quals2);
7278 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
7282 casts_away_constness (tree t1, tree t2)
7284 if (TREE_CODE (t2) == REFERENCE_TYPE)
7286 /* [expr.const.cast]
7288 Casting from an lvalue of type T1 to an lvalue of type T2
7289 using a reference cast casts away constness if a cast from an
7290 rvalue of type "pointer to T1" to the type "pointer to T2"
7291 casts away constness. */
7292 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
7293 return casts_away_constness (build_pointer_type (t1),
7294 build_pointer_type (TREE_TYPE (t2)));
7297 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
7298 /* [expr.const.cast]
7300 Casting from an rvalue of type "pointer to data member of X
7301 of type T1" to the type "pointer to data member of Y of type
7302 T2" casts away constness if a cast from an rvalue of type
7303 "pointer to T1" to the type "pointer to T2" casts away
7305 return casts_away_constness
7306 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
7307 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
7309 /* Casting away constness is only something that makes sense for
7310 pointer or reference types. */
7311 if (TREE_CODE (t1) != POINTER_TYPE
7312 || TREE_CODE (t2) != POINTER_TYPE)
7315 /* Top-level qualifiers don't matter. */
7316 t1 = TYPE_MAIN_VARIANT (t1);
7317 t2 = TYPE_MAIN_VARIANT (t2);
7318 casts_away_constness_r (&t1, &t2);
7319 if (!can_convert (t2, t1))
7325 /* If T is a REFERENCE_TYPE return the type to which T refers.
7326 Otherwise, return T itself. */
7329 non_reference (tree t)
7331 if (TREE_CODE (t) == REFERENCE_TYPE)
7337 /* Return nonzero if REF is an lvalue valid for this language;
7338 otherwise, print an error message and return zero. USE says
7339 how the lvalue is being used and so selects the error message. */
7342 lvalue_or_else (const_tree ref, enum lvalue_use use, tsubst_flags_t complain)
7344 int win = lvalue_p (ref);
7346 if (!win && (complain & tf_error))