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 Free Software Foundation, Inc.
4 Hacked by Michael Tiemann (tiemann@cygnus.com)
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to
20 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
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"
46 static tree pfn_from_ptrmemfunc (tree);
47 static tree convert_for_assignment (tree, tree, const char *, tree, int);
48 static tree cp_pointer_int_sum (enum tree_code, tree, tree);
49 static tree rationalize_conditional_expr (enum tree_code, tree);
50 static int comp_ptr_ttypes_real (tree, tree, int);
51 static bool comp_except_types (tree, tree, bool);
52 static bool comp_array_types (tree, tree, bool);
53 static tree common_base_type (tree, tree);
54 static tree pointer_diff (tree, tree, tree);
55 static tree get_delta_difference (tree, tree, bool, bool);
56 static void casts_away_constness_r (tree *, tree *);
57 static bool casts_away_constness (tree, tree);
58 static void maybe_warn_about_returning_address_of_local (tree);
59 static tree lookup_destructor (tree, tree, tree);
60 static tree convert_arguments (tree, tree, tree, int);
62 /* Do `exp = require_complete_type (exp);' to make sure exp
63 does not have an incomplete type. (That includes void types.)
64 Returns the error_mark_node if the VALUE does not have
65 complete type when this function returns. */
68 require_complete_type (tree value)
72 if (processing_template_decl || value == error_mark_node)
75 if (TREE_CODE (value) == OVERLOAD)
76 type = unknown_type_node;
78 type = TREE_TYPE (value);
80 if (type == error_mark_node)
81 return error_mark_node;
83 /* First, detect a valid value with a complete type. */
84 if (COMPLETE_TYPE_P (type))
87 if (complete_type_or_else (type, value))
90 return error_mark_node;
93 /* Try to complete TYPE, if it is incomplete. For example, if TYPE is
94 a template instantiation, do the instantiation. Returns TYPE,
95 whether or not it could be completed, unless something goes
96 horribly wrong, in which case the error_mark_node is returned. */
99 complete_type (tree type)
101 if (type == NULL_TREE)
102 /* Rather than crash, we return something sure to cause an error
104 return error_mark_node;
106 if (type == error_mark_node || COMPLETE_TYPE_P (type))
108 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
110 tree t = complete_type (TREE_TYPE (type));
111 unsigned int needs_constructing, has_nontrivial_dtor;
112 if (COMPLETE_TYPE_P (t) && !dependent_type_p (type))
115 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
117 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
118 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
120 TYPE_NEEDS_CONSTRUCTING (t) = needs_constructing;
121 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = has_nontrivial_dtor;
124 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
125 instantiate_class_template (TYPE_MAIN_VARIANT (type));
130 /* Like complete_type, but issue an error if the TYPE cannot be completed.
131 VALUE is used for informative diagnostics.
132 Returns NULL_TREE if the type cannot be made complete. */
135 complete_type_or_else (tree type, tree value)
137 type = complete_type (type);
138 if (type == error_mark_node)
139 /* We already issued an error. */
141 else if (!COMPLETE_TYPE_P (type))
143 cxx_incomplete_type_diagnostic (value, type, 0);
150 /* Return truthvalue of whether type of EXP is instantiated. */
153 type_unknown_p (tree exp)
155 return (TREE_CODE (exp) == TREE_LIST
156 || TREE_TYPE (exp) == unknown_type_node);
160 /* Return the common type of two parameter lists.
161 We assume that comptypes has already been done and returned 1;
162 if that isn't so, this may crash.
164 As an optimization, free the space we allocate if the parameter
165 lists are already common. */
168 commonparms (tree p1, tree p2)
170 tree oldargs = p1, newargs, n;
174 len = list_length (p1);
175 newargs = tree_last (p1);
177 if (newargs == void_list_node)
186 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
191 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
193 if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
195 TREE_PURPOSE (n) = TREE_PURPOSE (p1);
198 else if (! TREE_PURPOSE (p1))
200 if (TREE_PURPOSE (p2))
202 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
208 if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
210 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
212 if (TREE_VALUE (p1) != TREE_VALUE (p2))
215 TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2));
218 TREE_VALUE (n) = TREE_VALUE (p1);
226 /* Given a type, perhaps copied for a typedef,
227 find the "original" version of it. */
229 original_type (tree t)
231 int quals = cp_type_quals (t);
232 while (t != error_mark_node
233 && TYPE_NAME (t) != NULL_TREE)
235 tree x = TYPE_NAME (t);
236 if (TREE_CODE (x) != TYPE_DECL)
238 x = DECL_ORIGINAL_TYPE (x);
243 return cp_build_qualified_type (t, quals);
246 /* T1 and T2 are arithmetic or enumeration types. Return the type
247 that will result from the "usual arithmetic conversions" on T1 and
248 T2 as described in [expr]. */
251 type_after_usual_arithmetic_conversions (tree t1, tree t2)
253 enum tree_code code1 = TREE_CODE (t1);
254 enum tree_code code2 = TREE_CODE (t2);
257 /* FIXME: Attributes. */
258 gcc_assert (ARITHMETIC_TYPE_P (t1)
259 || TREE_CODE (t1) == COMPLEX_TYPE
260 || TREE_CODE (t1) == VECTOR_TYPE
261 || TREE_CODE (t1) == ENUMERAL_TYPE);
262 gcc_assert (ARITHMETIC_TYPE_P (t2)
263 || TREE_CODE (t2) == COMPLEX_TYPE
264 || TREE_CODE (t1) == VECTOR_TYPE
265 || TREE_CODE (t2) == ENUMERAL_TYPE);
267 /* In what follows, we slightly generalize the rules given in [expr] so
268 as to deal with `long long' and `complex'. First, merge the
270 attributes = (*targetm.merge_type_attributes) (t1, t2);
272 /* If one type is complex, form the common type of the non-complex
273 components, then make that complex. Use T1 or T2 if it is the
275 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
277 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
278 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
280 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
282 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
283 return build_type_attribute_variant (t1, attributes);
284 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
285 return build_type_attribute_variant (t2, attributes);
287 return build_type_attribute_variant (build_complex_type (subtype),
291 if (code1 == VECTOR_TYPE)
293 /* When we get here we should have two vectors of the same size.
294 Just prefer the unsigned one if present. */
295 if (TYPE_UNSIGNED (t1))
296 return build_type_attribute_variant (t1, attributes);
298 return build_type_attribute_variant (t2, attributes);
301 /* If only one is real, use it as the result. */
302 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
303 return build_type_attribute_variant (t1, attributes);
304 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
305 return build_type_attribute_variant (t2, attributes);
307 /* Perform the integral promotions. */
308 if (code1 != REAL_TYPE)
310 t1 = type_promotes_to (t1);
311 t2 = type_promotes_to (t2);
314 /* Both real or both integers; use the one with greater precision. */
315 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
316 return build_type_attribute_variant (t1, attributes);
317 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
318 return build_type_attribute_variant (t2, attributes);
320 /* The types are the same; no need to do anything fancy. */
321 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
322 return build_type_attribute_variant (t1, attributes);
324 if (code1 != REAL_TYPE)
326 /* If one is a sizetype, use it so size_binop doesn't blow up. */
327 if (TYPE_IS_SIZETYPE (t1) > TYPE_IS_SIZETYPE (t2))
328 return build_type_attribute_variant (t1, attributes);
329 if (TYPE_IS_SIZETYPE (t2) > TYPE_IS_SIZETYPE (t1))
330 return build_type_attribute_variant (t2, attributes);
332 /* If one is unsigned long long, then convert the other to unsigned
334 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
335 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
336 return build_type_attribute_variant (long_long_unsigned_type_node,
338 /* If one is a long long, and the other is an unsigned long, and
339 long long can represent all the values of an unsigned long, then
340 convert to a long long. Otherwise, convert to an unsigned long
341 long. Otherwise, if either operand is long long, convert the
344 Since we're here, we know the TYPE_PRECISION is the same;
345 therefore converting to long long cannot represent all the values
346 of an unsigned long, so we choose unsigned long long in that
348 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
349 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
351 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
352 ? long_long_unsigned_type_node
353 : long_long_integer_type_node);
354 return build_type_attribute_variant (t, attributes);
357 /* Go through the same procedure, but for longs. */
358 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
359 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
360 return build_type_attribute_variant (long_unsigned_type_node,
362 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
363 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
365 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
366 ? long_unsigned_type_node : long_integer_type_node);
367 return build_type_attribute_variant (t, attributes);
369 /* Otherwise prefer the unsigned one. */
370 if (TYPE_UNSIGNED (t1))
371 return build_type_attribute_variant (t1, attributes);
373 return build_type_attribute_variant (t2, attributes);
377 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
378 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
379 return build_type_attribute_variant (long_double_type_node,
381 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
382 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
383 return build_type_attribute_variant (double_type_node,
385 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
386 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
387 return build_type_attribute_variant (float_type_node,
390 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
391 the standard C++ floating-point types. Logic earlier in this
392 function has already eliminated the possibility that
393 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
394 compelling reason to choose one or the other. */
395 return build_type_attribute_variant (t1, attributes);
399 /* Subroutine of composite_pointer_type to implement the recursive
400 case. See that function for documentation fo the parameters. */
403 composite_pointer_type_r (tree t1, tree t2, const char* location)
410 /* Determine the types pointed to by T1 and T2. */
411 if (TREE_CODE (t1) == POINTER_TYPE)
413 pointee1 = TREE_TYPE (t1);
414 pointee2 = TREE_TYPE (t2);
418 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
419 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
424 Otherwise, the composite pointer type is a pointer type
425 similar (_conv.qual_) to the type of one of the operands,
426 with a cv-qualification signature (_conv.qual_) that is the
427 union of the cv-qualification signatures of the operand
429 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
430 result_type = pointee1;
431 else if ((TREE_CODE (pointee1) == POINTER_TYPE
432 && TREE_CODE (pointee2) == POINTER_TYPE)
433 || (TYPE_PTR_TO_MEMBER_P (pointee1)
434 && TYPE_PTR_TO_MEMBER_P (pointee2)))
435 result_type = composite_pointer_type_r (pointee1, pointee2, location);
438 pedwarn ("%s between distinct pointer types %qT and %qT "
441 result_type = void_type_node;
443 result_type = cp_build_qualified_type (result_type,
444 (cp_type_quals (pointee1)
445 | cp_type_quals (pointee2)));
446 /* If the original types were pointers to members, so is the
448 if (TYPE_PTR_TO_MEMBER_P (t1))
450 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
451 TYPE_PTRMEM_CLASS_TYPE (t2)))
452 pedwarn ("%s between distinct pointer types %qT and %qT "
455 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
459 result_type = build_pointer_type (result_type);
461 /* Merge the attributes. */
462 attributes = (*targetm.merge_type_attributes) (t1, t2);
463 return build_type_attribute_variant (result_type, attributes);
466 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
467 ARG1 and ARG2 are the values with those types. The LOCATION is a
468 string describing the current location, in case an error occurs.
470 This routine also implements the computation of a common type for
471 pointers-to-members as per [expr.eq]. */
474 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
475 const char* location)
482 If one operand is a null pointer constant, the composite pointer
483 type is the type of the other operand. */
484 if (null_ptr_cst_p (arg1))
486 if (null_ptr_cst_p (arg2))
493 If one of the operands has type "pointer to cv1 void*", then
494 the other has type "pointer to cv2T", and the composite pointer
495 type is "pointer to cv12 void", where cv12 is the union of cv1
498 If either type is a pointer to void, make sure it is T1. */
499 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
507 /* Now, if T1 is a pointer to void, merge the qualifiers. */
508 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
513 if (pedantic && TYPE_PTRFN_P (t2))
514 pedwarn ("ISO C++ forbids %s between pointer of type %<void *%> "
515 "and pointer-to-function", location);
517 = cp_build_qualified_type (void_type_node,
518 (cp_type_quals (TREE_TYPE (t1))
519 | cp_type_quals (TREE_TYPE (t2))));
520 result_type = build_pointer_type (result_type);
521 /* Merge the attributes. */
522 attributes = (*targetm.merge_type_attributes) (t1, t2);
523 return build_type_attribute_variant (result_type, attributes);
526 if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE
527 && TREE_CODE (t2) == POINTER_TYPE)
529 if (objc_compare_types (t1, t2, -3, NULL_TREE))
533 /* [expr.eq] permits the application of a pointer conversion to
534 bring the pointers to a common type. */
535 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
536 && CLASS_TYPE_P (TREE_TYPE (t1))
537 && CLASS_TYPE_P (TREE_TYPE (t2))
538 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
541 class1 = TREE_TYPE (t1);
542 class2 = TREE_TYPE (t2);
544 if (DERIVED_FROM_P (class1, class2))
545 t2 = (build_pointer_type
546 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
547 else if (DERIVED_FROM_P (class2, class1))
548 t1 = (build_pointer_type
549 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
552 error ("%s between distinct pointer types %qT and %qT "
553 "lacks a cast", location, t1, t2);
554 return error_mark_node;
557 /* [expr.eq] permits the application of a pointer-to-member
558 conversion to change the class type of one of the types. */
559 else if (TYPE_PTR_TO_MEMBER_P (t1)
560 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
561 TYPE_PTRMEM_CLASS_TYPE (t2)))
563 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
564 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
566 if (DERIVED_FROM_P (class1, class2))
567 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
568 else if (DERIVED_FROM_P (class2, class1))
569 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
572 error ("%s between distinct pointer-to-member types %qT and %qT "
573 "lacks a cast", location, t1, t2);
574 return error_mark_node;
578 return composite_pointer_type_r (t1, t2, location);
581 /* Return the merged type of two types.
582 We assume that comptypes has already been done and returned 1;
583 if that isn't so, this may crash.
585 This just combines attributes and default arguments; any other
586 differences would cause the two types to compare unalike. */
589 merge_types (tree t1, tree t2)
591 enum tree_code code1;
592 enum tree_code code2;
595 /* Save time if the two types are the same. */
598 if (original_type (t1) == original_type (t2))
601 /* If one type is nonsense, use the other. */
602 if (t1 == error_mark_node)
604 if (t2 == error_mark_node)
607 /* Merge the attributes. */
608 attributes = (*targetm.merge_type_attributes) (t1, t2);
610 if (TYPE_PTRMEMFUNC_P (t1))
611 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
612 if (TYPE_PTRMEMFUNC_P (t2))
613 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
615 code1 = TREE_CODE (t1);
616 code2 = TREE_CODE (t2);
622 /* For two pointers, do this recursively on the target type. */
624 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
625 int quals = cp_type_quals (t1);
627 if (code1 == POINTER_TYPE)
628 t1 = build_pointer_type (target);
630 t1 = build_reference_type (target);
631 t1 = build_type_attribute_variant (t1, attributes);
632 t1 = cp_build_qualified_type (t1, quals);
634 if (TREE_CODE (target) == METHOD_TYPE)
635 t1 = build_ptrmemfunc_type (t1);
644 quals = cp_type_quals (t1);
645 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
646 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
647 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
649 t1 = cp_build_qualified_type (t1, quals);
655 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
656 /* Save space: see if the result is identical to one of the args. */
657 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
658 return build_type_attribute_variant (t1, attributes);
659 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
660 return build_type_attribute_variant (t2, attributes);
661 /* Merge the element types, and have a size if either arg has one. */
662 t1 = build_cplus_array_type
663 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
668 /* Function types: prefer the one that specified arg types.
669 If both do, merge the arg types. Also merge the return types. */
671 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
672 tree p1 = TYPE_ARG_TYPES (t1);
673 tree p2 = TYPE_ARG_TYPES (t2);
676 /* Save space: see if the result is identical to one of the args. */
677 if (valtype == TREE_TYPE (t1) && ! p2)
678 return cp_build_type_attribute_variant (t1, attributes);
679 if (valtype == TREE_TYPE (t2) && ! p1)
680 return cp_build_type_attribute_variant (t2, attributes);
682 /* Simple way if one arg fails to specify argument types. */
683 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
685 rval = build_function_type (valtype, p2);
686 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
687 rval = build_exception_variant (rval, raises);
688 return cp_build_type_attribute_variant (rval, attributes);
690 raises = TYPE_RAISES_EXCEPTIONS (t1);
691 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
693 rval = build_function_type (valtype, p1);
695 rval = build_exception_variant (rval, raises);
696 return cp_build_type_attribute_variant (rval, attributes);
699 rval = build_function_type (valtype, commonparms (p1, p2));
700 t1 = build_exception_variant (rval, raises);
706 /* Get this value the long way, since TYPE_METHOD_BASETYPE
707 is just the main variant of this. */
708 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
709 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
712 /* If this was a member function type, get back to the
713 original type of type member function (i.e., without
714 the class instance variable up front. */
715 t1 = build_function_type (TREE_TYPE (t1),
716 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
717 t2 = build_function_type (TREE_TYPE (t2),
718 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
719 t3 = merge_types (t1, t2);
720 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
721 TYPE_ARG_TYPES (t3));
722 t1 = build_exception_variant (t3, raises);
727 /* There is no need to merge attributes into a TYPENAME_TYPE.
728 When the type is instantiated it will have whatever
729 attributes result from the instantiation. */
735 if (attribute_list_equal (TYPE_ATTRIBUTES (t1), attributes))
737 else if (attribute_list_equal (TYPE_ATTRIBUTES (t2), attributes))
740 return cp_build_type_attribute_variant (t1, attributes);
743 /* Return the common type of two types.
744 We assume that comptypes has already been done and returned 1;
745 if that isn't so, this may crash.
747 This is the type for the result of most arithmetic operations
748 if the operands have the given two types. */
751 common_type (tree t1, tree t2)
753 enum tree_code code1;
754 enum tree_code code2;
756 /* If one type is nonsense, bail. */
757 if (t1 == error_mark_node || t2 == error_mark_node)
758 return error_mark_node;
760 code1 = TREE_CODE (t1);
761 code2 = TREE_CODE (t2);
763 if ((ARITHMETIC_TYPE_P (t1) || code1 == ENUMERAL_TYPE
764 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
765 && (ARITHMETIC_TYPE_P (t2) || code2 == ENUMERAL_TYPE
766 || code2 == COMPLEX_TYPE || code2 == VECTOR_TYPE))
767 return type_after_usual_arithmetic_conversions (t1, t2);
769 else if ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
770 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
771 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)))
772 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
778 /* Compare two exception specifier types for exactness or subsetness, if
779 allowed. Returns false for mismatch, true for match (same, or
782 [except.spec] "If a class X ... objects of class X or any class publicly
783 and unambiguously derived from X. Similarly, if a pointer type Y * ...
784 exceptions of type Y * or that are pointers to any type publicly and
785 unambiguously derived from Y. Otherwise a function only allows exceptions
786 that have the same type ..."
787 This does not mention cv qualifiers and is different to what throw
788 [except.throw] and catch [except.catch] will do. They will ignore the
789 top level cv qualifiers, and allow qualifiers in the pointer to class
792 We implement the letter of the standard. */
795 comp_except_types (tree a, tree b, bool exact)
797 if (same_type_p (a, b))
801 if (cp_type_quals (a) || cp_type_quals (b))
804 if (TREE_CODE (a) == POINTER_TYPE
805 && TREE_CODE (b) == POINTER_TYPE)
809 if (cp_type_quals (a) || cp_type_quals (b))
813 if (TREE_CODE (a) != RECORD_TYPE
814 || TREE_CODE (b) != RECORD_TYPE)
817 if (PUBLICLY_UNIQUELY_DERIVED_P (a, b))
823 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
824 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
825 otherwise it must be exact. Exception lists are unordered, but
826 we've already filtered out duplicates. Most lists will be in order,
827 we should try to make use of that. */
830 comp_except_specs (tree t1, tree t2, bool exact)
839 if (t1 == NULL_TREE) /* T1 is ... */
840 return t2 == NULL_TREE || !exact;
841 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
842 return t2 != NULL_TREE && !TREE_VALUE (t2);
843 if (t2 == NULL_TREE) /* T2 is ... */
845 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
848 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
849 Count how many we find, to determine exactness. For exact matching and
850 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
852 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
854 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
856 tree a = TREE_VALUE (probe);
857 tree b = TREE_VALUE (t2);
859 if (comp_except_types (a, b, exact))
861 if (probe == base && exact)
862 base = TREE_CHAIN (probe);
867 if (probe == NULL_TREE)
870 return !exact || base == NULL_TREE || length == list_length (t1);
873 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
874 [] can match [size]. */
877 comp_array_types (tree t1, tree t2, bool allow_redeclaration)
886 /* The type of the array elements must be the same. */
887 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
890 d1 = TYPE_DOMAIN (t1);
891 d2 = TYPE_DOMAIN (t2);
896 /* If one of the arrays is dimensionless, and the other has a
897 dimension, they are of different types. However, it is valid to
905 declarations for an array object can specify
906 array types that differ by the presence or absence of a major
907 array bound (_dcl.array_). */
909 return allow_redeclaration;
911 /* Check that the dimensions are the same. */
913 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
915 max1 = TYPE_MAX_VALUE (d1);
916 max2 = TYPE_MAX_VALUE (d2);
917 if (processing_template_decl && !abi_version_at_least (2)
918 && !value_dependent_expression_p (max1)
919 && !value_dependent_expression_p (max2))
921 /* With abi-1 we do not fold non-dependent array bounds, (and
922 consequently mangle them incorrectly). We must therefore
923 fold them here, to verify the domains have the same
929 if (!cp_tree_equal (max1, max2))
935 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
936 is a bitwise-or of the COMPARE_* flags. */
939 comptypes (tree t1, tree t2, int strict)
944 /* Suppress errors caused by previously reported errors. */
945 if (t1 == error_mark_node || t2 == error_mark_node)
948 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
950 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
951 current instantiation. */
952 if (TREE_CODE (t1) == TYPENAME_TYPE)
954 tree resolved = resolve_typename_type (t1, /*only_current_p=*/true);
956 if (resolved != error_mark_node)
960 if (TREE_CODE (t2) == TYPENAME_TYPE)
962 tree resolved = resolve_typename_type (t2, /*only_current_p=*/true);
964 if (resolved != error_mark_node)
968 /* If either type is the internal version of sizetype, use the
970 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
971 && TYPE_ORIG_SIZE_TYPE (t1))
972 t1 = TYPE_ORIG_SIZE_TYPE (t1);
974 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
975 && TYPE_ORIG_SIZE_TYPE (t2))
976 t2 = TYPE_ORIG_SIZE_TYPE (t2);
978 if (TYPE_PTRMEMFUNC_P (t1))
979 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
980 if (TYPE_PTRMEMFUNC_P (t2))
981 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
983 /* Different classes of types can't be compatible. */
984 if (TREE_CODE (t1) != TREE_CODE (t2))
987 /* Qualifiers must match. For array types, we will check when we
988 recur on the array element types. */
989 if (TREE_CODE (t1) != ARRAY_TYPE
990 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
992 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
995 /* Allow for two different type nodes which have essentially the same
996 definition. Note that we already checked for equality of the type
997 qualifiers (just above). */
999 if (TREE_CODE (t1) != ARRAY_TYPE
1000 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
1003 /* Compare the types. Break out if they could be the same. */
1004 switch (TREE_CODE (t1))
1006 case TEMPLATE_TEMPLATE_PARM:
1007 case BOUND_TEMPLATE_TEMPLATE_PARM:
1008 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1009 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
1011 if (!comp_template_parms
1012 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1013 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1015 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1017 /* Don't check inheritance. */
1018 strict = COMPARE_STRICT;
1023 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1024 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1025 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1026 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1029 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1031 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1037 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1038 strict & ~COMPARE_REDECLARATION))
1040 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1045 case REFERENCE_TYPE:
1046 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1047 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)
1048 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1054 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1056 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1061 /* Target types must match incl. qualifiers. */
1062 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1066 case TEMPLATE_TYPE_PARM:
1067 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1068 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
1073 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1074 TYPENAME_TYPE_FULLNAME (t2)))
1076 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1080 case UNBOUND_CLASS_TEMPLATE:
1081 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1083 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1088 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1093 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1094 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1102 /* If we get here, we know that from a target independent POV the
1103 types are the same. Make sure the target attributes are also
1105 return targetm.comp_type_attributes (t1, t2);
1108 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1111 at_least_as_qualified_p (tree type1, tree type2)
1113 int q1 = cp_type_quals (type1);
1114 int q2 = cp_type_quals (type2);
1116 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1117 return (q1 & q2) == q2;
1120 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1121 more cv-qualified that TYPE1, and 0 otherwise. */
1124 comp_cv_qualification (tree type1, tree type2)
1126 int q1 = cp_type_quals (type1);
1127 int q2 = cp_type_quals (type2);
1132 if ((q1 & q2) == q2)
1134 else if ((q1 & q2) == q1)
1140 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1141 subset of the cv-qualification signature of TYPE2, and the types
1142 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1145 comp_cv_qual_signature (tree type1, tree type2)
1147 if (comp_ptr_ttypes_real (type2, type1, -1))
1149 else if (comp_ptr_ttypes_real (type1, type2, -1))
1155 /* If two types share a common base type, return that basetype.
1156 If there is not a unique most-derived base type, this function
1157 returns ERROR_MARK_NODE. */
1160 common_base_type (tree tt1, tree tt2)
1162 tree best = NULL_TREE;
1165 /* If one is a baseclass of another, that's good enough. */
1166 if (UNIQUELY_DERIVED_FROM_P (tt1, tt2))
1168 if (UNIQUELY_DERIVED_FROM_P (tt2, tt1))
1171 /* Otherwise, try to find a unique baseclass of TT1
1172 that is shared by TT2, and follow that down. */
1173 for (i = BINFO_N_BASE_BINFOS (TYPE_BINFO (tt1))-1; i >= 0; i--)
1175 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (tt1), i));
1176 tree trial = common_base_type (basetype, tt2);
1180 if (trial == error_mark_node)
1182 if (best == NULL_TREE)
1184 else if (best != trial)
1185 return error_mark_node;
1190 for (i = BINFO_N_BASE_BINFOS (TYPE_BINFO (tt2))-1; i >= 0; i--)
1192 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (tt2), i));
1193 tree trial = common_base_type (tt1, basetype);
1197 if (trial == error_mark_node)
1199 if (best == NULL_TREE)
1201 else if (best != trial)
1202 return error_mark_node;
1208 /* Subroutines of `comptypes'. */
1210 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1211 equivalent in the sense that functions with those parameter types
1212 can have equivalent types. The two lists must be equivalent,
1213 element by element. */
1216 compparms (tree parms1, tree parms2)
1220 /* An unspecified parmlist matches any specified parmlist
1221 whose argument types don't need default promotions. */
1223 for (t1 = parms1, t2 = parms2;
1225 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1227 /* If one parmlist is shorter than the other,
1228 they fail to match. */
1231 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1238 /* Process a sizeof or alignof expression where the operand is a
1242 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1247 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1248 if (type == error_mark_node)
1249 return error_mark_node;
1251 type = non_reference (type);
1252 if (TREE_CODE (type) == METHOD_TYPE)
1254 if (complain && (pedantic || warn_pointer_arith))
1255 pedwarn ("invalid application of %qs to a member function",
1256 operator_name_info[(int) op].name);
1257 value = size_one_node;
1260 dependent_p = dependent_type_p (type);
1262 complete_type (type);
1264 /* VLA types will have a non-constant size. In the body of an
1265 uninstantiated template, we don't need to try to compute the
1266 value, because the sizeof expression is not an integral
1267 constant expression in that case. And, if we do try to
1268 compute the value, we'll likely end up with SAVE_EXPRs, which
1269 the template substitution machinery does not expect to see. */
1270 || (processing_template_decl
1271 && COMPLETE_TYPE_P (type)
1272 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST))
1274 value = build_min (op, size_type_node, type);
1275 TREE_READONLY (value) = 1;
1279 return c_sizeof_or_alignof_type (complete_type (type),
1284 /* Process a sizeof expression where the operand is an expression. */
1287 cxx_sizeof_expr (tree e)
1289 if (e == error_mark_node)
1290 return error_mark_node;
1292 if (processing_template_decl)
1294 e = build_min (SIZEOF_EXPR, size_type_node, e);
1295 TREE_SIDE_EFFECTS (e) = 0;
1296 TREE_READONLY (e) = 1;
1301 if (TREE_CODE (e) == COMPONENT_REF
1302 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1303 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1305 error ("invalid application of %<sizeof%> to a bit-field");
1308 else if (is_overloaded_fn (e))
1310 pedwarn ("ISO C++ forbids applying %<sizeof%> to an expression of "
1314 else if (type_unknown_p (e))
1316 cxx_incomplete_type_error (e, TREE_TYPE (e));
1322 return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, true);
1325 /* Implement the __alignof keyword: Return the minimum required
1326 alignment of E, measured in bytes. For VAR_DECL's and
1327 FIELD_DECL's return DECL_ALIGN (which can be set from an
1328 "aligned" __attribute__ specification). */
1331 cxx_alignof_expr (tree e)
1335 if (e == error_mark_node)
1336 return error_mark_node;
1338 if (processing_template_decl)
1340 e = build_min (ALIGNOF_EXPR, size_type_node, e);
1341 TREE_SIDE_EFFECTS (e) = 0;
1342 TREE_READONLY (e) = 1;
1347 if (TREE_CODE (e) == VAR_DECL)
1348 t = size_int (DECL_ALIGN_UNIT (e));
1349 else if (TREE_CODE (e) == COMPONENT_REF
1350 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1351 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1353 error ("invalid application of %<__alignof%> to a bit-field");
1356 else if (TREE_CODE (e) == COMPONENT_REF
1357 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL)
1358 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1)));
1359 else if (is_overloaded_fn (e))
1361 pedwarn ("ISO C++ forbids applying %<__alignof%> to an expression of "
1365 else if (type_unknown_p (e))
1367 cxx_incomplete_type_error (e, TREE_TYPE (e));
1371 return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR, true);
1373 return fold_convert (size_type_node, t);
1376 /* Process a sizeof or alignof expression E with code OP where the operand
1377 is an expression. */
1380 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op)
1382 if (op == SIZEOF_EXPR)
1383 return cxx_sizeof_expr (e);
1385 return cxx_alignof_expr (e);
1388 /* EXPR is being used in a context that is not a function call.
1393 The expression can be used only as the left-hand operand of a
1394 member function call.
1396 [expr.mptr.operator]
1398 If the result of .* or ->* is a function, then that result can be
1399 used only as the operand for the function call operator ().
1401 by issuing an error message if appropriate. Returns true iff EXPR
1402 violates these rules. */
1405 invalid_nonstatic_memfn_p (tree expr)
1407 if (TREE_CODE (TREE_TYPE (expr)) == METHOD_TYPE)
1409 error ("invalid use of non-static member function");
1415 /* If EXP is a reference to a bitfield, and the type of EXP does not
1416 match the declared type of the bitfield, return the declared type
1417 of the bitfield. Otherwise, return NULL_TREE. */
1420 is_bitfield_expr_with_lowered_type (tree exp)
1424 if (TREE_CODE (exp) == COND_EXPR)
1426 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)))
1428 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2));
1430 if (TREE_CODE (exp) != COMPONENT_REF)
1432 field = TREE_OPERAND (exp, 1);
1433 if (TREE_CODE (field) != FIELD_DECL || !DECL_C_BIT_FIELD (field))
1435 if (same_type_ignoring_top_level_qualifiers_p
1436 (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field)))
1438 return DECL_BIT_FIELD_TYPE (field);
1441 /* Perform the conversions in [expr] that apply when an lvalue appears
1442 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1443 function-to-pointer conversions. In addition, manifest constants
1444 are replaced by their values, and bitfield references are converted
1445 to their declared types.
1447 Although the returned value is being used as an rvalue, this
1448 function does not wrap the returned expression in a
1449 NON_LVALUE_EXPR; the caller is expected to be mindful of the fact
1450 that the return value is no longer an lvalue. */
1453 decay_conversion (tree exp)
1456 enum tree_code code;
1458 type = TREE_TYPE (exp);
1459 if (type == error_mark_node)
1460 return error_mark_node;
1462 if (type_unknown_p (exp))
1464 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1465 return error_mark_node;
1468 exp = decl_constant_value (exp);
1469 if (error_operand_p (exp))
1470 return error_mark_node;
1472 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1473 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1474 code = TREE_CODE (type);
1475 if (code == VOID_TYPE)
1477 error ("void value not ignored as it ought to be");
1478 return error_mark_node;
1480 if (invalid_nonstatic_memfn_p (exp))
1481 return error_mark_node;
1482 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1483 return build_unary_op (ADDR_EXPR, exp, 0);
1484 if (code == ARRAY_TYPE)
1489 if (TREE_CODE (exp) == INDIRECT_REF)
1490 return build_nop (build_pointer_type (TREE_TYPE (type)),
1491 TREE_OPERAND (exp, 0));
1493 if (TREE_CODE (exp) == COMPOUND_EXPR)
1495 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1496 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1497 TREE_OPERAND (exp, 0), op1);
1501 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1503 error ("invalid use of non-lvalue array");
1504 return error_mark_node;
1507 ptrtype = build_pointer_type (TREE_TYPE (type));
1509 if (TREE_CODE (exp) == VAR_DECL)
1511 if (!cxx_mark_addressable (exp))
1512 return error_mark_node;
1513 adr = build_nop (ptrtype, build_address (exp));
1516 /* This way is better for a COMPONENT_REF since it can
1517 simplify the offset for a component. */
1518 adr = build_unary_op (ADDR_EXPR, exp, 1);
1519 return cp_convert (ptrtype, adr);
1522 /* If a bitfield is used in a context where integral promotion
1523 applies, then the caller is expected to have used
1524 default_conversion. That function promotes bitfields correctly
1525 before calling this function. At this point, if we have a
1526 bitfield referenced, we may assume that is not subject to
1527 promotion, and that, therefore, the type of the resulting rvalue
1528 is the declared type of the bitfield. */
1529 exp = convert_bitfield_to_declared_type (exp);
1531 /* We do not call rvalue() here because we do not want to wrap EXP
1532 in a NON_LVALUE_EXPR. */
1536 Non-class rvalues always have cv-unqualified types. */
1537 type = TREE_TYPE (exp);
1538 if (!CLASS_TYPE_P (type) && cp_type_quals (type))
1539 exp = build_nop (TYPE_MAIN_VARIANT (type), exp);
1544 /* Perform prepatory conversions, as part of the "usual arithmetic
1545 conversions". In particular, as per [expr]:
1547 Whenever an lvalue expression appears as an operand of an
1548 operator that expects the rvalue for that operand, the
1549 lvalue-to-rvalue, array-to-pointer, or function-to-pointer
1550 standard conversions are applied to convert the expression to an
1553 In addition, we perform integral promotions here, as those are
1554 applied to both operands to a binary operator before determining
1555 what additional conversions should apply. */
1558 default_conversion (tree exp)
1560 /* Perform the integral promotions first so that bitfield
1561 expressions (which may promote to "int", even if the bitfield is
1562 declared "unsigned") are promoted correctly. */
1563 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1564 exp = perform_integral_promotions (exp);
1565 /* Perform the other conversions. */
1566 exp = decay_conversion (exp);
1571 /* EXPR is an expression with an integral or enumeration type.
1572 Perform the integral promotions in [conv.prom], and return the
1576 perform_integral_promotions (tree expr)
1583 If the bitfield has an enumerated type, it is treated as any
1584 other value of that type for promotion purposes. */
1585 type = is_bitfield_expr_with_lowered_type (expr);
1586 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
1587 type = TREE_TYPE (expr);
1588 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1589 promoted_type = type_promotes_to (type);
1590 if (type != promoted_type)
1591 expr = cp_convert (promoted_type, expr);
1595 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1599 inline_conversion (tree exp)
1601 if (TREE_CODE (exp) == FUNCTION_DECL)
1602 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1607 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1608 decay_conversion to one. */
1611 string_conv_p (tree totype, tree exp, int warn)
1615 if (TREE_CODE (totype) != POINTER_TYPE)
1618 t = TREE_TYPE (totype);
1619 if (!same_type_p (t, char_type_node)
1620 && !same_type_p (t, wchar_type_node))
1623 if (TREE_CODE (exp) == STRING_CST)
1625 /* Make sure that we don't try to convert between char and wchar_t. */
1626 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1631 /* Is this a string constant which has decayed to 'const char *'? */
1632 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1633 if (!same_type_p (TREE_TYPE (exp), t))
1636 if (TREE_CODE (exp) != ADDR_EXPR
1637 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1641 /* This warning is not very useful, as it complains about printf. */
1643 warning (OPT_Wwrite_strings,
1644 "deprecated conversion from string constant to %qT",
1650 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1651 can, for example, use as an lvalue. This code used to be in
1652 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1653 expressions, where we're dealing with aggregates. But now it's again only
1654 called from unary_complex_lvalue. The case (in particular) that led to
1655 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1659 rationalize_conditional_expr (enum tree_code code, tree t)
1661 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1662 the first operand is always the one to be used if both operands
1663 are equal, so we know what conditional expression this used to be. */
1664 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1666 /* The following code is incorrect if either operand side-effects. */
1667 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0))
1668 && !TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)));
1670 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1671 ? LE_EXPR : GE_EXPR),
1672 TREE_OPERAND (t, 0),
1673 TREE_OPERAND (t, 1),
1674 /*overloaded_p=*/NULL),
1675 build_unary_op (code, TREE_OPERAND (t, 0), 0),
1676 build_unary_op (code, TREE_OPERAND (t, 1), 0));
1680 build_conditional_expr (TREE_OPERAND (t, 0),
1681 build_unary_op (code, TREE_OPERAND (t, 1), 0),
1682 build_unary_op (code, TREE_OPERAND (t, 2), 0));
1685 /* Given the TYPE of an anonymous union field inside T, return the
1686 FIELD_DECL for the field. If not found return NULL_TREE. Because
1687 anonymous unions can nest, we must also search all anonymous unions
1688 that are directly reachable. */
1691 lookup_anon_field (tree t, tree type)
1695 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1697 if (TREE_STATIC (field))
1699 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1702 /* If we find it directly, return the field. */
1703 if (DECL_NAME (field) == NULL_TREE
1704 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1709 /* Otherwise, it could be nested, search harder. */
1710 if (DECL_NAME (field) == NULL_TREE
1711 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1713 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1721 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1722 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1723 non-NULL, it indicates the path to the base used to name MEMBER.
1724 If PRESERVE_REFERENCE is true, the expression returned will have
1725 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1726 returned will have the type referred to by the reference.
1728 This function does not perform access control; that is either done
1729 earlier by the parser when the name of MEMBER is resolved to MEMBER
1730 itself, or later when overload resolution selects one of the
1731 functions indicated by MEMBER. */
1734 build_class_member_access_expr (tree object, tree member,
1735 tree access_path, bool preserve_reference)
1739 tree result = NULL_TREE;
1741 if (error_operand_p (object) || error_operand_p (member))
1742 return error_mark_node;
1744 gcc_assert (DECL_P (member) || BASELINK_P (member));
1748 The type of the first expression shall be "class object" (of a
1750 object_type = TREE_TYPE (object);
1751 if (!currently_open_class (object_type)
1752 && !complete_type_or_else (object_type, object))
1753 return error_mark_node;
1754 if (!CLASS_TYPE_P (object_type))
1756 error ("request for member %qD in %qE, which is of non-class type %qT",
1757 member, object, object_type);
1758 return error_mark_node;
1761 /* The standard does not seem to actually say that MEMBER must be a
1762 member of OBJECT_TYPE. However, that is clearly what is
1764 if (DECL_P (member))
1766 member_scope = DECL_CLASS_CONTEXT (member);
1768 if (TREE_DEPRECATED (member))
1769 warn_deprecated_use (member);
1772 member_scope = BINFO_TYPE (BASELINK_BINFO (member));
1773 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1774 presently be the anonymous union. Go outwards until we find a
1775 type related to OBJECT_TYPE. */
1776 while (ANON_AGGR_TYPE_P (member_scope)
1777 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1779 member_scope = TYPE_CONTEXT (member_scope);
1780 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1782 if (TREE_CODE (member) == FIELD_DECL)
1783 error ("invalid use of nonstatic data member %qE", member);
1785 error ("%qD is not a member of %qT", member, object_type);
1786 return error_mark_node;
1789 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1790 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1791 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1793 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1795 object = build_indirect_ref (temp, NULL);
1798 /* In [expr.ref], there is an explicit list of the valid choices for
1799 MEMBER. We check for each of those cases here. */
1800 if (TREE_CODE (member) == VAR_DECL)
1802 /* A static data member. */
1804 /* If OBJECT has side-effects, they are supposed to occur. */
1805 if (TREE_SIDE_EFFECTS (object))
1806 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1808 else if (TREE_CODE (member) == FIELD_DECL)
1810 /* A non-static data member. */
1815 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1816 && integer_zerop (TREE_OPERAND (object, 0)));
1818 /* Convert OBJECT to the type of MEMBER. */
1819 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1820 TYPE_MAIN_VARIANT (member_scope)))
1825 binfo = lookup_base (access_path ? access_path : object_type,
1826 member_scope, ba_unique, &kind);
1827 if (binfo == error_mark_node)
1828 return error_mark_node;
1830 /* It is invalid to try to get to a virtual base of a
1831 NULL object. The most common cause is invalid use of
1833 if (null_object_p && kind == bk_via_virtual)
1835 error ("invalid access to non-static data member %qD of "
1838 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
1839 return error_mark_node;
1842 /* Convert to the base. */
1843 object = build_base_path (PLUS_EXPR, object, binfo,
1845 /* If we found the base successfully then we should be able
1846 to convert to it successfully. */
1847 gcc_assert (object != error_mark_node);
1850 /* Complain about other invalid uses of offsetof, even though they will
1851 give the right answer. Note that we complain whether or not they
1852 actually used the offsetof macro, since there's no way to know at this
1853 point. So we just give a warning, instead of a pedwarn. */
1854 /* Do not produce this warning for base class field references, because
1855 we know for a fact that didn't come from offsetof. This does occur
1856 in various testsuite cases where a null object is passed where a
1857 vtable access is required. */
1858 if (null_object_p && warn_invalid_offsetof
1859 && CLASSTYPE_NON_POD_P (object_type)
1860 && !DECL_FIELD_IS_BASE (member)
1861 && !skip_evaluation)
1863 warning (0, "invalid access to non-static data member %qD of NULL object",
1865 warning (0, "(perhaps the %<offsetof%> macro was used incorrectly)");
1868 /* If MEMBER is from an anonymous aggregate, we have converted
1869 OBJECT so that it refers to the class containing the
1870 anonymous union. Generate a reference to the anonymous union
1871 itself, and recur to find MEMBER. */
1872 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
1873 /* When this code is called from build_field_call, the
1874 object already has the type of the anonymous union.
1875 That is because the COMPONENT_REF was already
1876 constructed, and was then disassembled before calling
1877 build_field_call. After the function-call code is
1878 cleaned up, this waste can be eliminated. */
1879 && (!same_type_ignoring_top_level_qualifiers_p
1880 (TREE_TYPE (object), DECL_CONTEXT (member))))
1882 tree anonymous_union;
1884 anonymous_union = lookup_anon_field (TREE_TYPE (object),
1885 DECL_CONTEXT (member));
1886 object = build_class_member_access_expr (object,
1888 /*access_path=*/NULL_TREE,
1889 preserve_reference);
1892 /* Compute the type of the field, as described in [expr.ref]. */
1893 type_quals = TYPE_UNQUALIFIED;
1894 member_type = TREE_TYPE (member);
1895 if (TREE_CODE (member_type) != REFERENCE_TYPE)
1897 type_quals = (cp_type_quals (member_type)
1898 | cp_type_quals (object_type));
1900 /* A field is const (volatile) if the enclosing object, or the
1901 field itself, is const (volatile). But, a mutable field is
1902 not const, even within a const object. */
1903 if (DECL_MUTABLE_P (member))
1904 type_quals &= ~TYPE_QUAL_CONST;
1905 member_type = cp_build_qualified_type (member_type, type_quals);
1908 result = build3 (COMPONENT_REF, member_type, object, member,
1910 result = fold_if_not_in_template (result);
1912 /* Mark the expression const or volatile, as appropriate. Even
1913 though we've dealt with the type above, we still have to mark the
1914 expression itself. */
1915 if (type_quals & TYPE_QUAL_CONST)
1916 TREE_READONLY (result) = 1;
1917 if (type_quals & TYPE_QUAL_VOLATILE)
1918 TREE_THIS_VOLATILE (result) = 1;
1920 else if (BASELINK_P (member))
1922 /* The member is a (possibly overloaded) member function. */
1926 /* If the MEMBER is exactly one static member function, then we
1927 know the type of the expression. Otherwise, we must wait
1928 until overload resolution has been performed. */
1929 functions = BASELINK_FUNCTIONS (member);
1930 if (TREE_CODE (functions) == FUNCTION_DECL
1931 && DECL_STATIC_FUNCTION_P (functions))
1932 type = TREE_TYPE (functions);
1934 type = unknown_type_node;
1935 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1936 base. That will happen when the function is called. */
1937 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
1939 else if (TREE_CODE (member) == CONST_DECL)
1941 /* The member is an enumerator. */
1943 /* If OBJECT has side-effects, they are supposed to occur. */
1944 if (TREE_SIDE_EFFECTS (object))
1945 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
1950 error ("invalid use of %qD", member);
1951 return error_mark_node;
1954 if (!preserve_reference)
1957 If E2 is declared to have type "reference to T", then ... the
1958 type of E1.E2 is T. */
1959 result = convert_from_reference (result);
1964 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1965 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1968 lookup_destructor (tree object, tree scope, tree dtor_name)
1970 tree object_type = TREE_TYPE (object);
1971 tree dtor_type = TREE_OPERAND (dtor_name, 0);
1974 if (scope && !check_dtor_name (scope, dtor_type))
1976 error ("qualified type %qT does not match destructor name ~%qT",
1978 return error_mark_node;
1980 if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
1982 error ("the type being destroyed is %qT, but the destructor refers to %qT",
1983 TYPE_MAIN_VARIANT (object_type), dtor_type);
1984 return error_mark_node;
1986 expr = lookup_member (dtor_type, complete_dtor_identifier,
1987 /*protect=*/1, /*want_type=*/false);
1988 expr = (adjust_result_of_qualified_name_lookup
1989 (expr, dtor_type, object_type));
1993 /* An expression of the form "A::template B" has been resolved to
1994 DECL. Issue a diagnostic if B is not a template or template
1998 check_template_keyword (tree decl)
2000 /* The standard says:
2004 If a name prefixed by the keyword template is not a member
2005 template, the program is ill-formed.
2007 DR 228 removed the restriction that the template be a member
2010 DR 96, if accepted would add the further restriction that explicit
2011 template arguments must be provided if the template keyword is
2012 used, but, as of 2005-10-16, that DR is still in "drafting". If
2013 this DR is accepted, then the semantic checks here can be
2014 simplified, as the entity named must in fact be a template
2015 specialization, rather than, as at present, a set of overloaded
2016 functions containing at least one template function. */
2017 if (TREE_CODE (decl) != TEMPLATE_DECL
2018 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
2020 if (!is_overloaded_fn (decl))
2021 pedwarn ("%qD is not a template", decl);
2026 if (BASELINK_P (fns))
2027 fns = BASELINK_FUNCTIONS (fns);
2030 tree fn = OVL_CURRENT (fns);
2031 if (TREE_CODE (fn) == TEMPLATE_DECL
2032 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2034 if (TREE_CODE (fn) == FUNCTION_DECL
2035 && DECL_USE_TEMPLATE (fn)
2036 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
2038 fns = OVL_NEXT (fns);
2041 pedwarn ("%qD is not a template", decl);
2046 /* This function is called by the parser to process a class member
2047 access expression of the form OBJECT.NAME. NAME is a node used by
2048 the parser to represent a name; it is not yet a DECL. It may,
2049 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2050 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2051 there is no reason to do the lookup twice, so the parser keeps the
2052 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2053 be a template via the use of the "A::template B" syntax. */
2056 finish_class_member_access_expr (tree object, tree name, bool template_p)
2061 tree access_path = NULL_TREE;
2062 tree orig_object = object;
2063 tree orig_name = name;
2065 if (object == error_mark_node || name == error_mark_node)
2066 return error_mark_node;
2068 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2069 if (!objc_is_public (object, name))
2070 return error_mark_node;
2072 object_type = TREE_TYPE (object);
2074 if (processing_template_decl)
2076 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2077 dependent_type_p (object_type)
2078 /* If NAME is just an IDENTIFIER_NODE, then the expression
2080 || TREE_CODE (object) == IDENTIFIER_NODE
2081 /* If NAME is "f<args>", where either 'f' or 'args' is
2082 dependent, then the expression is dependent. */
2083 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2084 && dependent_template_id_p (TREE_OPERAND (name, 0),
2085 TREE_OPERAND (name, 1)))
2086 /* If NAME is "T::X" where "T" is dependent, then the
2087 expression is dependent. */
2088 || (TREE_CODE (name) == SCOPE_REF
2089 && TYPE_P (TREE_OPERAND (name, 0))
2090 && dependent_type_p (TREE_OPERAND (name, 0))))
2091 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2092 object = build_non_dependent_expr (object);
2097 The type of the first expression shall be "class object" (of a
2099 if (!currently_open_class (object_type)
2100 && !complete_type_or_else (object_type, object))
2101 return error_mark_node;
2102 if (!CLASS_TYPE_P (object_type))
2104 error ("request for member %qD in %qE, which is of non-class type %qT",
2105 name, object, object_type);
2106 return error_mark_node;
2109 if (BASELINK_P (name))
2110 /* A member function that has already been looked up. */
2114 bool is_template_id = false;
2115 tree template_args = NULL_TREE;
2118 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2120 is_template_id = true;
2121 template_args = TREE_OPERAND (name, 1);
2122 name = TREE_OPERAND (name, 0);
2124 if (TREE_CODE (name) == OVERLOAD)
2125 name = DECL_NAME (get_first_fn (name));
2126 else if (DECL_P (name))
2127 name = DECL_NAME (name);
2130 if (TREE_CODE (name) == SCOPE_REF)
2132 /* A qualified name. The qualifying class or namespace `S'
2133 has already been looked up; it is either a TYPE or a
2135 scope = TREE_OPERAND (name, 0);
2136 name = TREE_OPERAND (name, 1);
2138 /* If SCOPE is a namespace, then the qualified name does not
2139 name a member of OBJECT_TYPE. */
2140 if (TREE_CODE (scope) == NAMESPACE_DECL)
2142 error ("%<%D::%D%> is not a member of %qT",
2143 scope, name, object_type);
2144 return error_mark_node;
2147 gcc_assert (CLASS_TYPE_P (scope));
2148 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2149 || TREE_CODE (name) == BIT_NOT_EXPR);
2151 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2152 access_path = lookup_base (object_type, scope, ba_check, NULL);
2153 if (access_path == error_mark_node)
2154 return error_mark_node;
2157 error ("%qT is not a base of %qT", scope, object_type);
2158 return error_mark_node;
2164 access_path = object_type;
2167 if (TREE_CODE (name) == BIT_NOT_EXPR)
2168 member = lookup_destructor (object, scope, name);
2171 /* Look up the member. */
2172 member = lookup_member (access_path, name, /*protect=*/1,
2173 /*want_type=*/false);
2174 if (member == NULL_TREE)
2176 error ("%qD has no member named %qE", object_type, name);
2177 return error_mark_node;
2179 if (member == error_mark_node)
2180 return error_mark_node;
2185 tree template = member;
2187 if (BASELINK_P (template))
2188 template = lookup_template_function (template, template_args);
2191 error ("%qD is not a member template function", name);
2192 return error_mark_node;
2197 if (TREE_DEPRECATED (member))
2198 warn_deprecated_use (member);
2201 check_template_keyword (member);
2203 expr = build_class_member_access_expr (object, member, access_path,
2204 /*preserve_reference=*/false);
2205 if (processing_template_decl && expr != error_mark_node)
2207 if (BASELINK_P (member))
2209 if (TREE_CODE (orig_name) == SCOPE_REF)
2210 BASELINK_QUALIFIED_P (member) = 1;
2213 return build_min_non_dep (COMPONENT_REF, expr,
2214 orig_object, orig_name,
2221 /* Return an expression for the MEMBER_NAME field in the internal
2222 representation of PTRMEM, a pointer-to-member function. (Each
2223 pointer-to-member function type gets its own RECORD_TYPE so it is
2224 more convenient to access the fields by name than by FIELD_DECL.)
2225 This routine converts the NAME to a FIELD_DECL and then creates the
2226 node for the complete expression. */
2229 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2235 /* This code is a stripped down version of
2236 build_class_member_access_expr. It does not work to use that
2237 routine directly because it expects the object to be of class
2239 ptrmem_type = TREE_TYPE (ptrmem);
2240 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2241 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2242 /*want_type=*/false);
2243 member_type = cp_build_qualified_type (TREE_TYPE (member),
2244 cp_type_quals (ptrmem_type));
2245 return fold_build3 (COMPONENT_REF, member_type,
2246 ptrmem, member, NULL_TREE);
2249 /* Given an expression PTR for a pointer, return an expression
2250 for the value pointed to.
2251 ERRORSTRING is the name of the operator to appear in error messages.
2253 This function may need to overload OPERATOR_FNNAME.
2254 Must also handle REFERENCE_TYPEs for C++. */
2257 build_x_indirect_ref (tree expr, const char *errorstring)
2259 tree orig_expr = expr;
2262 if (processing_template_decl)
2264 if (type_dependent_expression_p (expr))
2265 return build_min_nt (INDIRECT_REF, expr);
2266 expr = build_non_dependent_expr (expr);
2269 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2270 NULL_TREE, /*overloaded_p=*/NULL);
2272 rval = build_indirect_ref (expr, errorstring);
2274 if (processing_template_decl && rval != error_mark_node)
2275 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2281 build_indirect_ref (tree ptr, const char *errorstring)
2285 if (ptr == error_mark_node)
2286 return error_mark_node;
2288 if (ptr == current_class_ptr)
2289 return current_class_ref;
2291 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2292 ? ptr : decay_conversion (ptr));
2293 type = TREE_TYPE (pointer);
2295 if (POINTER_TYPE_P (type))
2299 If the type of the expression is "pointer to T," the type
2300 of the result is "T."
2302 We must use the canonical variant because certain parts of
2303 the back end, like fold, do pointer comparisons between
2305 tree t = canonical_type_variant (TREE_TYPE (type));
2307 if (VOID_TYPE_P (t))
2309 /* A pointer to incomplete type (other than cv void) can be
2310 dereferenced [expr.unary.op]/1 */
2311 error ("%qT is not a pointer-to-object type", type);
2312 return error_mark_node;
2314 else if (TREE_CODE (pointer) == ADDR_EXPR
2315 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2316 /* The POINTER was something like `&x'. We simplify `*&x' to
2318 return TREE_OPERAND (pointer, 0);
2321 tree ref = build1 (INDIRECT_REF, t, pointer);
2323 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2324 so that we get the proper error message if the result is used
2325 to assign to. Also, &* is supposed to be a no-op. */
2326 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2327 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2328 TREE_SIDE_EFFECTS (ref)
2329 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2333 /* `pointer' won't be an error_mark_node if we were given a
2334 pointer to member, so it's cool to check for this here. */
2335 else if (TYPE_PTR_TO_MEMBER_P (type))
2336 error ("invalid use of %qs on pointer to member", errorstring);
2337 else if (pointer != error_mark_node)
2340 error ("invalid type argument of %qs", errorstring);
2342 error ("invalid type argument");
2344 return error_mark_node;
2347 /* This handles expressions of the form "a[i]", which denotes
2350 This is logically equivalent in C to *(a+i), but we may do it differently.
2351 If A is a variable or a member, we generate a primitive ARRAY_REF.
2352 This avoids forcing the array out of registers, and can work on
2353 arrays that are not lvalues (for example, members of structures returned
2356 If INDEX is of some user-defined type, it must be converted to
2357 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2358 will inherit the type of the array, which will be some pointer type. */
2361 build_array_ref (tree array, tree idx)
2365 error ("subscript missing in array reference");
2366 return error_mark_node;
2369 if (TREE_TYPE (array) == error_mark_node
2370 || TREE_TYPE (idx) == error_mark_node)
2371 return error_mark_node;
2373 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2375 switch (TREE_CODE (array))
2379 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2380 return build2 (COMPOUND_EXPR, TREE_TYPE (value),
2381 TREE_OPERAND (array, 0), value);
2385 return build_conditional_expr
2386 (TREE_OPERAND (array, 0),
2387 build_array_ref (TREE_OPERAND (array, 1), idx),
2388 build_array_ref (TREE_OPERAND (array, 2), idx));
2394 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2398 warn_array_subscript_with_type_char (idx);
2400 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2402 error ("array subscript is not an integer");
2403 return error_mark_node;
2406 /* Apply integral promotions *after* noticing character types.
2407 (It is unclear why we do these promotions -- the standard
2408 does not say that we should. In fact, the natural thing would
2409 seem to be to convert IDX to ptrdiff_t; we're performing
2410 pointer arithmetic.) */
2411 idx = perform_integral_promotions (idx);
2413 /* An array that is indexed by a non-constant
2414 cannot be stored in a register; we must be able to do
2415 address arithmetic on its address.
2416 Likewise an array of elements of variable size. */
2417 if (TREE_CODE (idx) != INTEGER_CST
2418 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2419 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2422 if (!cxx_mark_addressable (array))
2423 return error_mark_node;
2426 /* An array that is indexed by a constant value which is not within
2427 the array bounds cannot be stored in a register either; because we
2428 would get a crash in store_bit_field/extract_bit_field when trying
2429 to access a non-existent part of the register. */
2430 if (TREE_CODE (idx) == INTEGER_CST
2431 && TYPE_DOMAIN (TREE_TYPE (array))
2432 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2434 if (!cxx_mark_addressable (array))
2435 return error_mark_node;
2438 if (pedantic && !lvalue_p (array))
2439 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2441 /* Note in C++ it is valid to subscript a `register' array, since
2442 it is valid to take the address of something with that
2443 storage specification. */
2447 while (TREE_CODE (foo) == COMPONENT_REF)
2448 foo = TREE_OPERAND (foo, 0);
2449 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2450 warning (OPT_Wextra, "subscripting array declared %<register%>");
2453 type = TREE_TYPE (TREE_TYPE (array));
2454 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2455 /* Array ref is const/volatile if the array elements are
2456 or if the array is.. */
2457 TREE_READONLY (rval)
2458 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2459 TREE_SIDE_EFFECTS (rval)
2460 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2461 TREE_THIS_VOLATILE (rval)
2462 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2463 return require_complete_type (fold_if_not_in_template (rval));
2467 tree ar = default_conversion (array);
2468 tree ind = default_conversion (idx);
2470 /* Put the integer in IND to simplify error checking. */
2471 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2478 if (ar == error_mark_node)
2481 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2483 error ("subscripted value is neither array nor pointer");
2484 return error_mark_node;
2486 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2488 error ("array subscript is not an integer");
2489 return error_mark_node;
2492 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2497 /* Resolve a pointer to member function. INSTANCE is the object
2498 instance to use, if the member points to a virtual member.
2500 This used to avoid checking for virtual functions if basetype
2501 has no virtual functions, according to an earlier ANSI draft.
2502 With the final ISO C++ rules, such an optimization is
2503 incorrect: A pointer to a derived member can be static_cast
2504 to pointer-to-base-member, as long as the dynamic object
2505 later has the right member. */
2508 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2510 if (TREE_CODE (function) == OFFSET_REF)
2511 function = TREE_OPERAND (function, 1);
2513 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2515 tree idx, delta, e1, e2, e3, vtbl, basetype;
2516 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2518 tree instance_ptr = *instance_ptrptr;
2519 tree instance_save_expr = 0;
2520 if (instance_ptr == error_mark_node)
2522 if (TREE_CODE (function) == PTRMEM_CST)
2524 /* Extracting the function address from a pmf is only
2525 allowed with -Wno-pmf-conversions. It only works for
2527 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2528 e1 = convert (fntype, e1);
2533 error ("object missing in use of %qE", function);
2534 return error_mark_node;
2538 if (TREE_SIDE_EFFECTS (instance_ptr))
2539 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2541 if (TREE_SIDE_EFFECTS (function))
2542 function = save_expr (function);
2544 /* Start by extracting all the information from the PMF itself. */
2545 e3 = pfn_from_ptrmemfunc (function);
2546 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2547 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2548 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2550 case ptrmemfunc_vbit_in_pfn:
2551 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2552 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2555 case ptrmemfunc_vbit_in_delta:
2556 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2557 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2564 /* Convert down to the right base before using the instance. A
2565 special case is that in a pointer to member of class C, C may
2566 be incomplete. In that case, the function will of course be
2567 a member of C, and no conversion is required. In fact,
2568 lookup_base will fail in that case, because incomplete
2569 classes do not have BINFOs. */
2570 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2571 if (!same_type_ignoring_top_level_qualifiers_p
2572 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2574 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2575 basetype, ba_check, NULL);
2576 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2578 if (instance_ptr == error_mark_node)
2579 return error_mark_node;
2581 /* ...and then the delta in the PMF. */
2582 instance_ptr = build2 (PLUS_EXPR, TREE_TYPE (instance_ptr),
2583 instance_ptr, delta);
2585 /* Hand back the adjusted 'this' argument to our caller. */
2586 *instance_ptrptr = instance_ptr;
2588 /* Next extract the vtable pointer from the object. */
2589 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2591 vtbl = build_indirect_ref (vtbl, NULL);
2593 /* Finally, extract the function pointer from the vtable. */
2594 e2 = fold_build2 (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx);
2595 e2 = build_indirect_ref (e2, NULL);
2596 TREE_CONSTANT (e2) = 1;
2597 TREE_INVARIANT (e2) = 1;
2599 /* When using function descriptors, the address of the
2600 vtable entry is treated as a function pointer. */
2601 if (TARGET_VTABLE_USES_DESCRIPTORS)
2602 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2603 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2605 TREE_TYPE (e2) = TREE_TYPE (e3);
2606 e1 = build_conditional_expr (e1, e2, e3);
2608 /* Make sure this doesn't get evaluated first inside one of the
2609 branches of the COND_EXPR. */
2610 if (instance_save_expr)
2611 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2612 instance_save_expr, e1);
2620 build_function_call (tree function, tree params)
2622 tree fntype, fndecl;
2623 tree coerced_params;
2624 tree name = NULL_TREE;
2626 tree original = function;
2628 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2629 expressions, like those used for ObjC messenger dispatches. */
2630 function = objc_rewrite_function_call (function, params);
2632 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2633 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2634 if (TREE_CODE (function) == NOP_EXPR
2635 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2636 function = TREE_OPERAND (function, 0);
2638 if (TREE_CODE (function) == FUNCTION_DECL)
2640 name = DECL_NAME (function);
2642 mark_used (function);
2645 /* Convert anything with function type to a pointer-to-function. */
2646 if (pedantic && DECL_MAIN_P (function))
2647 pedwarn ("ISO C++ forbids calling %<::main%> from within program");
2649 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2650 (because calling an inline function does not mean the function
2651 needs to be separately compiled). */
2653 if (DECL_INLINE (function))
2654 function = inline_conversion (function);
2656 function = build_addr_func (function);
2662 function = build_addr_func (function);
2665 if (function == error_mark_node)
2666 return error_mark_node;
2668 fntype = TREE_TYPE (function);
2670 if (TYPE_PTRMEMFUNC_P (fntype))
2672 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2673 "function in %<%E (...)%>",
2675 return error_mark_node;
2678 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2679 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2681 if (!((TREE_CODE (fntype) == POINTER_TYPE
2682 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2684 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2686 error ("%qE cannot be used as a function", original);
2687 return error_mark_node;
2690 /* fntype now gets the type of function pointed to. */
2691 fntype = TREE_TYPE (fntype);
2693 /* Convert the parameters to the types declared in the
2694 function prototype, or apply default promotions. */
2696 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2697 params, fndecl, LOOKUP_NORMAL);
2698 if (coerced_params == error_mark_node)
2699 return error_mark_node;
2701 /* Check for errors in format strings and inappropriately
2704 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params,
2705 TYPE_ARG_TYPES (fntype));
2707 return build_cxx_call (function, coerced_params);
2710 /* Convert the actual parameter expressions in the list VALUES
2711 to the types in the list TYPELIST.
2712 If parmdecls is exhausted, or when an element has NULL as its type,
2713 perform the default conversions.
2715 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2717 This is also where warnings about wrong number of args are generated.
2719 Return a list of expressions for the parameters as converted.
2721 Both VALUES and the returned value are chains of TREE_LIST nodes
2722 with the elements of the list in the TREE_VALUE slots of those nodes.
2724 In C++, unspecified trailing parameters can be filled in with their
2725 default arguments, if such were specified. Do so here. */
2728 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2730 tree typetail, valtail;
2731 tree result = NULL_TREE;
2732 const char *called_thing = 0;
2735 /* Argument passing is always copy-initialization. */
2736 flags |= LOOKUP_ONLYCONVERTING;
2740 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2742 if (DECL_NAME (fndecl) == NULL_TREE
2743 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2744 called_thing = "constructor";
2746 called_thing = "member function";
2749 called_thing = "function";
2752 for (valtail = values, typetail = typelist;
2754 valtail = TREE_CHAIN (valtail), i++)
2756 tree type = typetail ? TREE_VALUE (typetail) : 0;
2757 tree val = TREE_VALUE (valtail);
2759 if (val == error_mark_node || type == error_mark_node)
2760 return error_mark_node;
2762 if (type == void_type_node)
2766 error ("too many arguments to %s %q+#D", called_thing, fndecl);
2767 error ("at this point in file");
2770 error ("too many arguments to function");
2771 /* In case anybody wants to know if this argument
2774 TREE_TYPE (tree_last (result)) = error_mark_node;
2778 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2779 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2780 if (TREE_CODE (val) == NOP_EXPR
2781 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2782 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2783 val = TREE_OPERAND (val, 0);
2785 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2787 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2788 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2789 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2790 val = decay_conversion (val);
2793 if (val == error_mark_node)
2794 return error_mark_node;
2798 /* Formal parm type is specified by a function prototype. */
2801 if (!COMPLETE_TYPE_P (complete_type (type)))
2804 error ("parameter %P of %qD has incomplete type %qT",
2807 error ("parameter %P has incomplete type %qT", i, type);
2808 parmval = error_mark_node;
2812 parmval = convert_for_initialization
2813 (NULL_TREE, type, val, flags,
2814 "argument passing", fndecl, i);
2815 parmval = convert_for_arg_passing (type, parmval);
2818 if (parmval == error_mark_node)
2819 return error_mark_node;
2821 result = tree_cons (NULL_TREE, parmval, result);
2825 if (fndecl && DECL_BUILT_IN (fndecl)
2826 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2827 /* Don't do ellipsis conversion for __built_in_constant_p
2828 as this will result in spurious warnings for non-POD
2830 val = require_complete_type (val);
2832 val = convert_arg_to_ellipsis (val);
2834 result = tree_cons (NULL_TREE, val, result);
2838 typetail = TREE_CHAIN (typetail);
2841 if (typetail != 0 && typetail != void_list_node)
2843 /* See if there are default arguments that can be used. */
2844 if (TREE_PURPOSE (typetail)
2845 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2847 for (; typetail != void_list_node; ++i)
2850 = convert_default_arg (TREE_VALUE (typetail),
2851 TREE_PURPOSE (typetail),
2854 if (parmval == error_mark_node)
2855 return error_mark_node;
2857 result = tree_cons (0, parmval, result);
2858 typetail = TREE_CHAIN (typetail);
2859 /* ends with `...'. */
2860 if (typetail == NULL_TREE)
2868 error ("too few arguments to %s %q+#D", called_thing, fndecl);
2869 error ("at this point in file");
2872 error ("too few arguments to function");
2873 return error_mark_node;
2877 return nreverse (result);
2880 /* Build a binary-operation expression, after performing default
2881 conversions on the operands. CODE is the kind of expression to build. */
2884 build_x_binary_op (enum tree_code code, tree arg1, tree arg2,
2894 if (processing_template_decl)
2896 if (type_dependent_expression_p (arg1)
2897 || type_dependent_expression_p (arg2))
2898 return build_min_nt (code, arg1, arg2);
2899 arg1 = build_non_dependent_expr (arg1);
2900 arg2 = build_non_dependent_expr (arg2);
2903 if (code == DOTSTAR_EXPR)
2904 expr = build_m_component_ref (arg1, arg2);
2906 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
2909 if (processing_template_decl && expr != error_mark_node)
2910 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
2915 /* Build a binary-operation expression without default conversions.
2916 CODE is the kind of expression to build.
2917 This function differs from `build' in several ways:
2918 the data type of the result is computed and recorded in it,
2919 warnings are generated if arg data types are invalid,
2920 special handling for addition and subtraction of pointers is known,
2921 and some optimization is done (operations on narrow ints
2922 are done in the narrower type when that gives the same result).
2923 Constant folding is also done before the result is returned.
2925 Note that the operands will never have enumeral types
2926 because either they have just had the default conversions performed
2927 or they have both just been converted to some other type in which
2928 the arithmetic is to be done.
2930 C++: must do special pointer arithmetic when implementing
2931 multiple inheritance, and deal with pointer to member functions. */
2934 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2935 int convert_p ATTRIBUTE_UNUSED)
2938 enum tree_code code0, code1;
2940 const char *invalid_op_diag;
2942 /* Expression code to give to the expression when it is built.
2943 Normally this is CODE, which is what the caller asked for,
2944 but in some special cases we change it. */
2945 enum tree_code resultcode = code;
2947 /* Data type in which the computation is to be performed.
2948 In the simplest cases this is the common type of the arguments. */
2949 tree result_type = NULL;
2951 /* Nonzero means operands have already been type-converted
2952 in whatever way is necessary.
2953 Zero means they need to be converted to RESULT_TYPE. */
2956 /* Nonzero means create the expression with this type, rather than
2958 tree build_type = 0;
2960 /* Nonzero means after finally constructing the expression
2961 convert it to this type. */
2962 tree final_type = 0;
2966 /* Nonzero if this is an operation like MIN or MAX which can
2967 safely be computed in short if both args are promoted shorts.
2968 Also implies COMMON.
2969 -1 indicates a bitwise operation; this makes a difference
2970 in the exact conditions for when it is safe to do the operation
2971 in a narrower mode. */
2974 /* Nonzero if this is a comparison operation;
2975 if both args are promoted shorts, compare the original shorts.
2976 Also implies COMMON. */
2977 int short_compare = 0;
2979 /* Nonzero if this is a right-shift operation, which can be computed on the
2980 original short and then promoted if the operand is a promoted short. */
2981 int short_shift = 0;
2983 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2986 /* True if both operands have arithmetic type. */
2987 bool arithmetic_types_p;
2989 /* Apply default conversions. */
2993 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2994 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2995 || code == TRUTH_XOR_EXPR)
2997 if (!really_overloaded_fn (op0))
2998 op0 = decay_conversion (op0);
2999 if (!really_overloaded_fn (op1))
3000 op1 = decay_conversion (op1);
3004 if (!really_overloaded_fn (op0))
3005 op0 = default_conversion (op0);
3006 if (!really_overloaded_fn (op1))
3007 op1 = default_conversion (op1);
3010 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3011 STRIP_TYPE_NOPS (op0);
3012 STRIP_TYPE_NOPS (op1);
3014 /* DTRT if one side is an overloaded function, but complain about it. */
3015 if (type_unknown_p (op0))
3017 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3018 if (t != error_mark_node)
3020 pedwarn ("assuming cast to type %qT from overloaded function",
3025 if (type_unknown_p (op1))
3027 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3028 if (t != error_mark_node)
3030 pedwarn ("assuming cast to type %qT from overloaded function",
3036 type0 = TREE_TYPE (op0);
3037 type1 = TREE_TYPE (op1);
3039 /* The expression codes of the data types of the arguments tell us
3040 whether the arguments are integers, floating, pointers, etc. */
3041 code0 = TREE_CODE (type0);
3042 code1 = TREE_CODE (type1);
3044 /* If an error was already reported for one of the arguments,
3045 avoid reporting another error. */
3047 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3048 return error_mark_node;
3050 if ((invalid_op_diag
3051 = targetm.invalid_binary_op (code, type0, type1)))
3053 error (invalid_op_diag);
3054 return error_mark_node;
3060 /* Subtraction of two similar pointers.
3061 We must subtract them as integers, then divide by object size. */
3062 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3063 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3065 return pointer_diff (op0, op1, common_type (type0, type1));
3066 /* In all other cases except pointer - int, the usual arithmetic
3068 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
3073 /* The pointer - int case is just like pointer + int; fall
3076 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
3077 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
3081 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
3082 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
3083 if (processing_template_decl)
3085 result_type = TREE_TYPE (ptr_operand);
3088 return cp_pointer_int_sum (code,
3099 case TRUNC_DIV_EXPR:
3101 case FLOOR_DIV_EXPR:
3102 case ROUND_DIV_EXPR:
3103 case EXACT_DIV_EXPR:
3104 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3105 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3106 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3107 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3109 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
3110 warning (OPT_Wdiv_by_zero, "division by zero in %<%E / 0%>", op0);
3111 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
3112 warning (OPT_Wdiv_by_zero, "division by zero in %<%E / 0.%>", op0);
3114 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3115 code0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3116 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
3117 code1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3119 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
3120 resultcode = RDIV_EXPR;
3122 /* When dividing two signed integers, we have to promote to int.
3123 unless we divide by a constant != -1. Note that default
3124 conversion will have been performed on the operands at this
3125 point, so we have to dig out the original type to find out if
3127 shorten = ((TREE_CODE (op0) == NOP_EXPR
3128 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3129 || (TREE_CODE (op1) == INTEGER_CST
3130 && ! integer_all_onesp (op1)));
3139 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3140 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE))
3144 case TRUNC_MOD_EXPR:
3145 case FLOOR_MOD_EXPR:
3146 if (code1 == INTEGER_TYPE && integer_zerop (op1))
3147 warning (OPT_Wdiv_by_zero, "division by zero in %<%E %% 0%>", op0);
3148 else if (code1 == REAL_TYPE && real_zerop (op1))
3149 warning (OPT_Wdiv_by_zero, "division by zero in %<%E %% 0.%>", op0);
3151 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3153 /* Although it would be tempting to shorten always here, that loses
3154 on some targets, since the modulo instruction is undefined if the
3155 quotient can't be represented in the computation mode. We shorten
3156 only if unsigned or if dividing by something we know != -1. */
3157 shorten = ((TREE_CODE (op0) == NOP_EXPR
3158 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3159 || (TREE_CODE (op1) == INTEGER_CST
3160 && ! integer_all_onesp (op1)));
3165 case TRUTH_ANDIF_EXPR:
3166 case TRUTH_ORIF_EXPR:
3167 case TRUTH_AND_EXPR:
3169 result_type = boolean_type_node;
3172 /* Shift operations: result has same type as first operand;
3173 always convert second operand to int.
3174 Also set SHORT_SHIFT if shifting rightward. */
3177 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3179 result_type = type0;
3180 if (TREE_CODE (op1) == INTEGER_CST)
3182 if (tree_int_cst_lt (op1, integer_zero_node))
3183 warning (0, "right shift count is negative");
3186 if (! integer_zerop (op1))
3188 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3189 warning (0, "right shift count >= width of type");
3192 /* Convert the shift-count to an integer, regardless of
3193 size of value being shifted. */
3194 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3195 op1 = cp_convert (integer_type_node, op1);
3196 /* Avoid converting op1 to result_type later. */
3202 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3204 result_type = type0;
3205 if (TREE_CODE (op1) == INTEGER_CST)
3207 if (tree_int_cst_lt (op1, integer_zero_node))
3208 warning (0, "left shift count is negative");
3209 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3210 warning (0, "left shift count >= width of type");
3212 /* Convert the shift-count to an integer, regardless of
3213 size of value being shifted. */
3214 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3215 op1 = cp_convert (integer_type_node, op1);
3216 /* Avoid converting op1 to result_type later. */
3223 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3225 result_type = type0;
3226 if (TREE_CODE (op1) == INTEGER_CST)
3228 if (tree_int_cst_lt (op1, integer_zero_node))
3229 warning (0, "%s rotate count is negative",
3230 (code == LROTATE_EXPR) ? "left" : "right");
3231 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3232 warning (0, "%s rotate count >= width of type",
3233 (code == LROTATE_EXPR) ? "left" : "right");
3235 /* Convert the shift-count to an integer, regardless of
3236 size of value being shifted. */
3237 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3238 op1 = cp_convert (integer_type_node, op1);
3244 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
3245 warning (OPT_Wfloat_equal,
3246 "comparing floating point with == or != is unsafe");
3247 if ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3248 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0)))
3249 warning (OPT_Wstring_literal_comparison,
3250 "comparison with string literal");
3252 build_type = boolean_type_node;
3253 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3254 || code0 == COMPLEX_TYPE)
3255 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3256 || code1 == COMPLEX_TYPE))
3258 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3259 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3260 result_type = composite_pointer_type (type0, type1, op0, op1,
3262 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3263 && null_ptr_cst_p (op1))
3264 result_type = type0;
3265 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3266 && null_ptr_cst_p (op0))
3267 result_type = type1;
3268 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3270 result_type = type0;
3271 error ("ISO C++ forbids comparison between pointer and integer");
3273 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3275 result_type = type1;
3276 error ("ISO C++ forbids comparison between pointer and integer");
3278 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3280 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3281 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3282 result_type = TREE_TYPE (op0);
3284 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3285 return cp_build_binary_op (code, op1, op0);
3286 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
3287 && same_type_p (type0, type1))
3289 /* E will be the final comparison. */
3291 /* E1 and E2 are for scratch. */
3299 if (TREE_SIDE_EFFECTS (op0))
3300 op0 = save_expr (op0);
3301 if (TREE_SIDE_EFFECTS (op1))
3302 op1 = save_expr (op1);
3307 && (!op0.pfn || op0.delta == op1.delta))
3309 The reason for the `!op0.pfn' bit is that a NULL
3310 pointer-to-member is any member with a zero PFN; the
3311 DELTA field is unspecified. */
3312 pfn0 = pfn_from_ptrmemfunc (op0);
3313 pfn1 = pfn_from_ptrmemfunc (op1);
3314 delta0 = build_ptrmemfunc_access_expr (op0,
3316 delta1 = build_ptrmemfunc_access_expr (op1,
3318 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
3319 e2 = cp_build_binary_op (EQ_EXPR,
3321 cp_convert (TREE_TYPE (pfn0),
3322 integer_zero_node));
3323 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
3324 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3325 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3326 if (code == EQ_EXPR)
3328 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3332 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3333 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3335 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3336 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3344 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3345 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3347 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3348 result_type = composite_pointer_type (type0, type1, op0, op1,
3356 if (TREE_CODE (orig_op0) == STRING_CST
3357 || TREE_CODE (orig_op1) == STRING_CST)
3358 warning (OPT_Wstring_literal_comparison,
3359 "comparison with string literal");
3361 build_type = boolean_type_node;
3362 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3363 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3365 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3366 result_type = composite_pointer_type (type0, type1, op0, op1,
3368 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3369 && integer_zerop (op1))
3370 result_type = type0;
3371 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3372 && integer_zerop (op0))
3373 result_type = type1;
3374 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3376 result_type = type0;
3377 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3379 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3381 result_type = type1;
3382 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3386 case UNORDERED_EXPR:
3393 build_type = integer_type_node;
3394 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3396 error ("unordered comparison on non-floating point argument");
3397 return error_mark_node;
3406 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3407 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3408 || code1 == COMPLEX_TYPE)))
3409 arithmetic_types_p = 1;
3412 arithmetic_types_p = 0;
3413 /* Vector arithmetic is only allowed when both sides are vectors. */
3414 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3416 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3417 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3420 binary_op_error (code);
3421 return error_mark_node;
3423 arithmetic_types_p = 1;
3426 /* Determine the RESULT_TYPE, if it is not already known. */
3428 && arithmetic_types_p
3429 && (shorten || common || short_compare))
3430 result_type = common_type (type0, type1);
3434 error ("invalid operands of types %qT and %qT to binary %qO",
3435 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3436 return error_mark_node;
3439 /* If we're in a template, the only thing we need to know is the
3441 if (processing_template_decl)
3442 return build2 (resultcode,
3443 build_type ? build_type : result_type,
3446 if (arithmetic_types_p)
3448 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3450 /* For certain operations (which identify themselves by shorten != 0)
3451 if both args were extended from the same smaller type,
3452 do the arithmetic in that type and then extend.
3454 shorten !=0 and !=1 indicates a bitwise operation.
3455 For them, this optimization is safe only if
3456 both args are zero-extended or both are sign-extended.
3457 Otherwise, we might change the result.
3458 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3459 but calculated in (unsigned short) it would be (unsigned short)-1. */
3461 if (shorten && none_complex)
3463 int unsigned0, unsigned1;
3464 tree arg0 = get_narrower (op0, &unsigned0);
3465 tree arg1 = get_narrower (op1, &unsigned1);
3466 /* UNS is 1 if the operation to be done is an unsigned one. */
3467 int uns = TYPE_UNSIGNED (result_type);
3470 final_type = result_type;
3472 /* Handle the case that OP0 does not *contain* a conversion
3473 but it *requires* conversion to FINAL_TYPE. */
3475 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3476 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
3477 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3478 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
3480 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3482 /* For bitwise operations, signedness of nominal type
3483 does not matter. Consider only how operands were extended. */
3487 /* Note that in all three cases below we refrain from optimizing
3488 an unsigned operation on sign-extended args.
3489 That would not be valid. */
3491 /* Both args variable: if both extended in same way
3492 from same width, do it in that width.
3493 Do it unsigned if args were zero-extended. */
3494 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3495 < TYPE_PRECISION (result_type))
3496 && (TYPE_PRECISION (TREE_TYPE (arg1))
3497 == TYPE_PRECISION (TREE_TYPE (arg0)))
3498 && unsigned0 == unsigned1
3499 && (unsigned0 || !uns))
3500 result_type = c_common_signed_or_unsigned_type
3501 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3502 else if (TREE_CODE (arg0) == INTEGER_CST
3503 && (unsigned1 || !uns)
3504 && (TYPE_PRECISION (TREE_TYPE (arg1))
3505 < TYPE_PRECISION (result_type))
3506 && (type = c_common_signed_or_unsigned_type
3507 (unsigned1, TREE_TYPE (arg1)),
3508 int_fits_type_p (arg0, type)))
3510 else if (TREE_CODE (arg1) == INTEGER_CST
3511 && (unsigned0 || !uns)
3512 && (TYPE_PRECISION (TREE_TYPE (arg0))
3513 < TYPE_PRECISION (result_type))
3514 && (type = c_common_signed_or_unsigned_type
3515 (unsigned0, TREE_TYPE (arg0)),
3516 int_fits_type_p (arg1, type)))
3520 /* Shifts can be shortened if shifting right. */
3525 tree arg0 = get_narrower (op0, &unsigned_arg);
3527 final_type = result_type;
3529 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3530 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
3532 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3533 /* We can shorten only if the shift count is less than the
3534 number of bits in the smaller type size. */
3535 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3536 /* If arg is sign-extended and then unsigned-shifted,
3537 we can simulate this with a signed shift in arg's type
3538 only if the extended result is at least twice as wide
3539 as the arg. Otherwise, the shift could use up all the
3540 ones made by sign-extension and bring in zeros.
3541 We can't optimize that case at all, but in most machines
3542 it never happens because available widths are 2**N. */
3543 && (!TYPE_UNSIGNED (final_type)
3545 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3546 <= TYPE_PRECISION (result_type))))
3548 /* Do an unsigned shift if the operand was zero-extended. */
3550 = c_common_signed_or_unsigned_type (unsigned_arg,
3552 /* Convert value-to-be-shifted to that type. */
3553 if (TREE_TYPE (op0) != result_type)
3554 op0 = cp_convert (result_type, op0);
3559 /* Comparison operations are shortened too but differently.
3560 They identify themselves by setting short_compare = 1. */
3564 /* Don't write &op0, etc., because that would prevent op0
3565 from being kept in a register.
3566 Instead, make copies of the our local variables and
3567 pass the copies by reference, then copy them back afterward. */
3568 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3569 enum tree_code xresultcode = resultcode;
3571 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3573 return cp_convert (boolean_type_node, val);
3574 op0 = xop0, op1 = xop1;
3576 resultcode = xresultcode;
3579 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3580 && warn_sign_compare
3581 /* Do not warn until the template is instantiated; we cannot
3582 bound the ranges of the arguments until that point. */
3583 && !processing_template_decl)
3585 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
3586 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3588 int unsignedp0, unsignedp1;
3589 tree primop0 = get_narrower (op0, &unsignedp0);
3590 tree primop1 = get_narrower (op1, &unsignedp1);
3592 /* Check for comparison of different enum types. */
3593 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3594 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3595 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3596 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3598 warning (0, "comparison between types %q#T and %q#T",
3599 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3602 /* Give warnings for comparisons between signed and unsigned
3603 quantities that may fail. */
3604 /* Do the checking based on the original operand trees, so that
3605 casts will be considered, but default promotions won't be. */
3607 /* Do not warn if the comparison is being done in a signed type,
3608 since the signed type will only be chosen if it can represent
3609 all the values of the unsigned type. */
3610 if (!TYPE_UNSIGNED (result_type))
3612 /* Do not warn if both operands are unsigned. */
3613 else if (op0_signed == op1_signed)
3615 /* Do not warn if the signed quantity is an unsuffixed
3616 integer literal (or some static constant expression
3617 involving such literals or a conditional expression
3618 involving such literals) and it is non-negative. */
3619 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3620 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3622 /* Do not warn if the comparison is an equality operation,
3623 the unsigned quantity is an integral constant and it does
3624 not use the most significant bit of result_type. */
3625 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3626 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3627 && int_fits_type_p (orig_op1, c_common_signed_type
3629 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3630 && int_fits_type_p (orig_op0, c_common_signed_type
3634 warning (0, "comparison between signed and unsigned integer expressions");
3636 /* Warn if two unsigned values are being compared in a size
3637 larger than their original size, and one (and only one) is the
3638 result of a `~' operator. This comparison will always fail.
3640 Also warn if one operand is a constant, and the constant does not
3641 have all bits set that are set in the ~ operand when it is
3644 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3645 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3647 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3648 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3649 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3650 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3652 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3655 HOST_WIDE_INT constant, mask;
3659 if (host_integerp (primop0, 0))
3662 unsignedp = unsignedp1;
3663 constant = tree_low_cst (primop0, 0);
3668 unsignedp = unsignedp0;
3669 constant = tree_low_cst (primop1, 0);
3672 bits = TYPE_PRECISION (TREE_TYPE (primop));
3673 if (bits < TYPE_PRECISION (result_type)
3674 && bits < HOST_BITS_PER_LONG && unsignedp)
3676 mask = (~ (HOST_WIDE_INT) 0) << bits;
3677 if ((mask & constant) != mask)
3678 warning (0, "comparison of promoted ~unsigned with constant");
3681 else if (unsignedp0 && unsignedp1
3682 && (TYPE_PRECISION (TREE_TYPE (primop0))
3683 < TYPE_PRECISION (result_type))
3684 && (TYPE_PRECISION (TREE_TYPE (primop1))
3685 < TYPE_PRECISION (result_type)))
3686 warning (0, "comparison of promoted ~unsigned with unsigned");
3691 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3692 Then the expression will be built.
3693 It will be given type FINAL_TYPE if that is nonzero;
3694 otherwise, it will be given type RESULT_TYPE. */
3696 /* Issue warnings about peculiar, but valid, uses of NULL. */
3697 if (/* It's reasonable to use pointer values as operands of &&
3698 and ||, so NULL is no exception. */
3699 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3700 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3701 (orig_op0 == null_node
3702 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3703 /* Or vice versa. */
3704 || (orig_op1 == null_node
3705 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3706 /* Or, both are NULL and the operation was not a comparison. */
3707 || (orig_op0 == null_node && orig_op1 == null_node
3708 && code != EQ_EXPR && code != NE_EXPR)))
3709 /* Some sort of arithmetic operation involving NULL was
3710 performed. Note that pointer-difference and pointer-addition
3711 have already been handled above, and so we don't end up here in
3713 warning (0, "NULL used in arithmetic");
3717 if (TREE_TYPE (op0) != result_type)
3718 op0 = cp_convert (result_type, op0);
3719 if (TREE_TYPE (op1) != result_type)
3720 op1 = cp_convert (result_type, op1);
3722 if (op0 == error_mark_node || op1 == error_mark_node)
3723 return error_mark_node;
3726 if (build_type == NULL_TREE)
3727 build_type = result_type;
3729 result = build2 (resultcode, build_type, op0, op1);
3730 result = fold_if_not_in_template (result);
3731 if (final_type != 0)
3732 result = cp_convert (final_type, result);
3736 /* Return a tree for the sum or difference (RESULTCODE says which)
3737 of pointer PTROP and integer INTOP. */
3740 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
3742 tree res_type = TREE_TYPE (ptrop);
3744 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3745 in certain circumstance (when it's valid to do so). So we need
3746 to make sure it's complete. We don't need to check here, if we
3747 can actually complete it at all, as those checks will be done in
3748 pointer_int_sum() anyway. */
3749 complete_type (TREE_TYPE (res_type));
3751 return pointer_int_sum (resultcode, ptrop,
3752 fold_if_not_in_template (intop));
3755 /* Return a tree for the difference of pointers OP0 and OP1.
3756 The resulting tree has type int. */
3759 pointer_diff (tree op0, tree op1, tree ptrtype)
3762 tree restype = ptrdiff_type_node;
3763 tree target_type = TREE_TYPE (ptrtype);
3765 if (!complete_type_or_else (target_type, NULL_TREE))
3766 return error_mark_node;
3768 if (pedantic || warn_pointer_arith)
3770 if (TREE_CODE (target_type) == VOID_TYPE)
3771 pedwarn ("ISO C++ forbids using pointer of type %<void *%> in subtraction");
3772 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3773 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3774 if (TREE_CODE (target_type) == METHOD_TYPE)
3775 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3778 /* First do the subtraction as integers;
3779 then drop through to build the divide operator. */
3781 op0 = cp_build_binary_op (MINUS_EXPR,
3782 cp_convert (restype, op0),
3783 cp_convert (restype, op1));
3785 /* This generates an error if op1 is a pointer to an incomplete type. */
3786 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3787 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3789 op1 = (TYPE_PTROB_P (ptrtype)
3790 ? size_in_bytes (target_type)
3791 : integer_one_node);
3793 /* Do the division. */
3795 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3796 return fold_if_not_in_template (result);
3799 /* Construct and perhaps optimize a tree representation
3800 for a unary operation. CODE, a tree_code, specifies the operation
3801 and XARG is the operand. */
3804 build_x_unary_op (enum tree_code code, tree xarg)
3806 tree orig_expr = xarg;
3810 if (processing_template_decl)
3812 if (type_dependent_expression_p (xarg))
3813 return build_min_nt (code, xarg, NULL_TREE);
3815 xarg = build_non_dependent_expr (xarg);
3820 /* [expr.unary.op] says:
3822 The address of an object of incomplete type can be taken.
3824 (And is just the ordinary address operator, not an overloaded
3825 "operator &".) However, if the type is a template
3826 specialization, we must complete the type at this point so that
3827 an overloaded "operator &" will be available if required. */
3828 if (code == ADDR_EXPR
3829 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3830 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
3831 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
3832 || (TREE_CODE (xarg) == OFFSET_REF)))
3833 /* Don't look for a function. */;
3835 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
3836 /*overloaded_p=*/NULL);
3837 if (!exp && code == ADDR_EXPR)
3839 /* A pointer to member-function can be formed only by saying
3841 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3842 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3844 if (TREE_CODE (xarg) != OFFSET_REF
3845 || !TYPE_P (TREE_OPERAND (xarg, 0)))
3847 error ("invalid use of %qE to form a pointer-to-member-function",
3849 if (TREE_CODE (xarg) != OFFSET_REF)
3850 inform (" a qualified-id is required");
3851 return error_mark_node;
3855 error ("parentheses around %qE cannot be used to form a"
3856 " pointer-to-member-function",
3858 PTRMEM_OK_P (xarg) = 1;
3862 if (TREE_CODE (xarg) == OFFSET_REF)
3864 ptrmem = PTRMEM_OK_P (xarg);
3866 if (!ptrmem && !flag_ms_extensions
3867 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3869 /* A single non-static member, make sure we don't allow a
3870 pointer-to-member. */
3871 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
3872 TREE_OPERAND (xarg, 0),
3873 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3874 PTRMEM_OK_P (xarg) = ptrmem;
3877 else if (TREE_CODE (xarg) == TARGET_EXPR)
3878 warning (0, "taking address of temporary");
3879 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3882 if (processing_template_decl && exp != error_mark_node)
3883 exp = build_min_non_dep (code, exp, orig_expr,
3884 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
3885 if (TREE_CODE (exp) == ADDR_EXPR)
3886 PTRMEM_OK_P (exp) = ptrmem;
3890 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3891 constants, where a null value is represented by an INTEGER_CST of
3895 cp_truthvalue_conversion (tree expr)
3897 tree type = TREE_TYPE (expr);
3898 if (TYPE_PTRMEM_P (type))
3899 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3901 return c_common_truthvalue_conversion (expr);
3904 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3907 condition_conversion (tree expr)
3910 if (processing_template_decl)
3912 t = perform_implicit_conversion (boolean_type_node, expr);
3913 t = fold_build_cleanup_point_expr (boolean_type_node, t);
3917 /* Return an ADDR_EXPR giving the address of T. This function
3918 attempts no optimizations or simplifications; it is a low-level
3922 build_address (tree t)
3926 if (error_operand_p (t) || !cxx_mark_addressable (t))
3927 return error_mark_node;
3929 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
3934 /* Return a NOP_EXPR converting EXPR to TYPE. */
3937 build_nop (tree type, tree expr)
3939 if (type == error_mark_node || error_operand_p (expr))
3941 return build1 (NOP_EXPR, type, expr);
3944 /* C++: Must handle pointers to members.
3946 Perhaps type instantiation should be extended to handle conversion
3947 from aggregates to types we don't yet know we want? (Or are those
3948 cases typically errors which should be reported?)
3950 NOCONVERT nonzero suppresses the default promotions
3951 (such as from short to int). */
3954 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3956 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3959 const char *errstring = NULL;
3961 const char *invalid_op_diag;
3963 if (arg == error_mark_node)
3964 return error_mark_node;
3966 if ((invalid_op_diag
3967 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
3972 error (invalid_op_diag);
3973 return error_mark_node;
3978 case UNARY_PLUS_EXPR:
3981 int flags = WANT_ARITH | WANT_ENUM;
3982 /* Unary plus (but not unary minus) is allowed on pointers. */
3983 if (code == UNARY_PLUS_EXPR)
3984 flags |= WANT_POINTER;
3985 arg = build_expr_type_conversion (flags, arg, true);
3987 errstring = (code == NEGATE_EXPR
3988 ? "wrong type argument to unary minus"
3989 : "wrong type argument to unary plus");
3992 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3993 arg = perform_integral_promotions (arg);
3995 /* Make sure the result is not an lvalue: a unary plus or minus
3996 expression is always a rvalue. */
4003 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4007 arg = default_conversion (arg);
4009 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
4011 errstring = "wrong type argument to bit-complement";
4012 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4013 arg = perform_integral_promotions (arg);
4017 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4018 errstring = "wrong type argument to abs";
4019 else if (!noconvert)
4020 arg = default_conversion (arg);
4024 /* Conjugating a real value is a no-op, but allow it anyway. */
4025 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4026 errstring = "wrong type argument to conjugation";
4027 else if (!noconvert)
4028 arg = default_conversion (arg);
4031 case TRUTH_NOT_EXPR:
4032 arg = perform_implicit_conversion (boolean_type_node, arg);
4033 val = invert_truthvalue (arg);
4034 if (arg != error_mark_node)
4036 errstring = "in argument to unary !";
4043 if (TREE_CODE (arg) == COMPLEX_CST)
4044 return TREE_REALPART (arg);
4045 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4047 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4048 return fold_if_not_in_template (arg);
4054 if (TREE_CODE (arg) == COMPLEX_CST)
4055 return TREE_IMAGPART (arg);
4056 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4058 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4059 return fold_if_not_in_template (arg);
4062 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4064 case PREINCREMENT_EXPR:
4065 case POSTINCREMENT_EXPR:
4066 case PREDECREMENT_EXPR:
4067 case POSTDECREMENT_EXPR:
4068 /* Handle complex lvalues (when permitted)
4069 by reduction to simpler cases. */
4071 val = unary_complex_lvalue (code, arg);
4075 /* Increment or decrement the real part of the value,
4076 and don't change the imaginary part. */
4077 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4081 arg = stabilize_reference (arg);
4082 real = build_unary_op (REALPART_EXPR, arg, 1);
4083 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
4084 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4085 build_unary_op (code, real, 1), imag);
4088 /* Report invalid types. */
4090 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4093 if (code == PREINCREMENT_EXPR)
4094 errstring ="no pre-increment operator for type";
4095 else if (code == POSTINCREMENT_EXPR)
4096 errstring ="no post-increment operator for type";
4097 else if (code == PREDECREMENT_EXPR)
4098 errstring ="no pre-decrement operator for type";
4100 errstring ="no post-decrement operator for type";
4104 /* Report something read-only. */
4106 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4107 || TREE_READONLY (arg))
4108 readonly_error (arg, ((code == PREINCREMENT_EXPR
4109 || code == POSTINCREMENT_EXPR)
4110 ? "increment" : "decrement"),
4115 tree result_type = TREE_TYPE (arg);
4117 arg = get_unwidened (arg, 0);
4118 argtype = TREE_TYPE (arg);
4120 /* ARM $5.2.5 last annotation says this should be forbidden. */
4121 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4122 pedwarn ("ISO C++ forbids %sing an enum",
4123 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4124 ? "increment" : "decrement");
4126 /* Compute the increment. */
4128 if (TREE_CODE (argtype) == POINTER_TYPE)
4130 tree type = complete_type (TREE_TYPE (argtype));
4132 if (!COMPLETE_OR_VOID_TYPE_P (type))
4133 error ("cannot %s a pointer to incomplete type %qT",
4134 ((code == PREINCREMENT_EXPR
4135 || code == POSTINCREMENT_EXPR)
4136 ? "increment" : "decrement"), TREE_TYPE (argtype));
4137 else if ((pedantic || warn_pointer_arith)
4138 && !TYPE_PTROB_P (argtype))
4139 pedwarn ("ISO C++ forbids %sing a pointer of type %qT",
4140 ((code == PREINCREMENT_EXPR
4141 || code == POSTINCREMENT_EXPR)
4142 ? "increment" : "decrement"), argtype);
4143 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4146 inc = integer_one_node;
4148 inc = cp_convert (argtype, inc);
4150 /* Handle incrementing a cast-expression. */
4152 switch (TREE_CODE (arg))
4157 case FIX_TRUNC_EXPR:
4158 case FIX_FLOOR_EXPR:
4159 case FIX_ROUND_EXPR:
4162 tree incremented, modify, value, compound;
4163 if (! lvalue_p (arg) && pedantic)
4164 pedwarn ("cast to non-reference type used as lvalue");
4165 arg = stabilize_reference (arg);
4166 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
4169 value = save_expr (arg);
4170 incremented = build2 (((code == PREINCREMENT_EXPR
4171 || code == POSTINCREMENT_EXPR)
4172 ? PLUS_EXPR : MINUS_EXPR),
4173 argtype, value, inc);
4175 modify = build_modify_expr (arg, NOP_EXPR, incremented);
4176 compound = build2 (COMPOUND_EXPR, TREE_TYPE (arg),
4179 /* Eliminate warning about unused result of + or -. */
4180 TREE_NO_WARNING (compound) = 1;
4188 /* Complain about anything else that is not a true lvalue. */
4189 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4190 || code == POSTINCREMENT_EXPR)
4191 ? lv_increment : lv_decrement)))
4192 return error_mark_node;
4194 /* Forbid using -- on `bool'. */
4195 if (TREE_TYPE (arg) == boolean_type_node)
4197 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4199 error ("invalid use of %<--%> on bool variable %qD", arg);
4200 return error_mark_node;
4202 val = boolean_increment (code, arg);
4205 val = build2 (code, TREE_TYPE (arg), arg, inc);
4207 TREE_SIDE_EFFECTS (val) = 1;
4208 return cp_convert (result_type, val);
4212 /* Note that this operation never does default_conversion
4213 regardless of NOCONVERT. */
4215 argtype = lvalue_type (arg);
4217 if (TREE_CODE (arg) == OFFSET_REF)
4220 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4222 tree type = build_pointer_type (TREE_TYPE (argtype));
4223 arg = build1 (CONVERT_EXPR, type, arg);
4226 else if (pedantic && DECL_MAIN_P (arg))
4228 pedwarn ("ISO C++ forbids taking address of function %<::main%>");
4230 /* Let &* cancel out to simplify resulting code. */
4231 if (TREE_CODE (arg) == INDIRECT_REF)
4233 /* We don't need to have `current_class_ptr' wrapped in a
4234 NON_LVALUE_EXPR node. */
4235 if (arg == current_class_ref)
4236 return current_class_ptr;
4238 arg = TREE_OPERAND (arg, 0);
4239 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4241 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4242 arg = build1 (CONVERT_EXPR, type, arg);
4245 /* Don't let this be an lvalue. */
4250 /* Uninstantiated types are all functions. Taking the
4251 address of a function is a no-op, so just return the
4254 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4255 || !IDENTIFIER_OPNAME_P (arg));
4257 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4258 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4260 /* They're trying to take the address of a unique non-static
4261 member function. This is ill-formed (except in MS-land),
4262 but let's try to DTRT.
4263 Note: We only handle unique functions here because we don't
4264 want to complain if there's a static overload; non-unique
4265 cases will be handled by instantiate_type. But we need to
4266 handle this case here to allow casts on the resulting PMF.
4267 We could defer this in non-MS mode, but it's easier to give
4268 a useful error here. */
4270 /* Inside constant member functions, the `this' pointer
4271 contains an extra const qualifier. TYPE_MAIN_VARIANT
4272 is used here to remove this const from the diagnostics
4273 and the created OFFSET_REF. */
4274 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4275 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4278 if (! flag_ms_extensions)
4280 tree name = DECL_NAME (fn);
4281 if (current_class_type
4282 && TREE_OPERAND (arg, 0) == current_class_ref)
4283 /* An expression like &memfn. */
4284 pedwarn ("ISO C++ forbids taking the address of an unqualified"
4285 " or parenthesized non-static member function to form"
4286 " a pointer to member function. Say %<&%T::%D%>",
4289 pedwarn ("ISO C++ forbids taking the address of a bound member"
4290 " function to form a pointer to member function."
4294 arg = build_offset_ref (base, fn, /*address_p=*/true);
4298 if (type_unknown_p (arg))
4299 return build1 (ADDR_EXPR, unknown_type_node, arg);
4301 /* Handle complex lvalues (when permitted)
4302 by reduction to simpler cases. */
4303 val = unary_complex_lvalue (code, arg);
4307 switch (TREE_CODE (arg))
4312 case FIX_TRUNC_EXPR:
4313 case FIX_FLOOR_EXPR:
4314 case FIX_ROUND_EXPR:
4316 if (! lvalue_p (arg) && pedantic)
4317 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4321 arg = BASELINK_FUNCTIONS (arg);
4325 arg = OVL_CURRENT (arg);
4329 /* Turn a reference to a non-static data member into a
4330 pointer-to-member. */
4335 if (!PTRMEM_OK_P (arg))
4336 return build_unary_op (code, arg, 0);
4338 t = TREE_OPERAND (arg, 1);
4339 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4341 error ("cannot create pointer to reference member %qD", t);
4342 return error_mark_node;
4345 type = build_ptrmem_type (context_for_name_lookup (t),
4347 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4355 /* Anything not already handled and not a true memory reference
4357 if (TREE_CODE (argtype) != FUNCTION_TYPE
4358 && TREE_CODE (argtype) != METHOD_TYPE
4359 && TREE_CODE (arg) != OFFSET_REF
4360 && !lvalue_or_else (arg, lv_addressof))
4361 return error_mark_node;
4363 if (argtype != error_mark_node)
4364 argtype = build_pointer_type (argtype);
4366 /* In a template, we are processing a non-dependent expression
4367 so we can just form an ADDR_EXPR with the correct type. */
4368 if (processing_template_decl)
4370 val = build_address (arg);
4371 if (TREE_CODE (arg) == OFFSET_REF)
4372 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4376 if (TREE_CODE (arg) != COMPONENT_REF)
4378 val = build_address (arg);
4379 if (TREE_CODE (arg) == OFFSET_REF)
4380 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4382 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4384 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4386 /* We can only get here with a single static member
4388 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4389 && DECL_STATIC_FUNCTION_P (fn));
4391 val = build_address (fn);
4392 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4393 /* Do not lose object's side effects. */
4394 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4395 TREE_OPERAND (arg, 0), val);
4397 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4399 error ("attempt to take address of bit-field structure member %qD",
4400 TREE_OPERAND (arg, 1));
4401 return error_mark_node;
4405 tree object = TREE_OPERAND (arg, 0);
4406 tree field = TREE_OPERAND (arg, 1);
4407 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4408 (TREE_TYPE (object), decl_type_context (field)));
4409 val = build_address (arg);
4412 if (TREE_CODE (argtype) == POINTER_TYPE
4413 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4415 build_ptrmemfunc_type (argtype);
4416 val = build_ptrmemfunc (argtype, val, 0,
4417 /*c_cast_p=*/false);
4429 argtype = TREE_TYPE (arg);
4430 return fold_if_not_in_template (build1 (code, argtype, arg));
4433 error ("%s", errstring);
4434 return error_mark_node;
4437 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4438 for certain kinds of expressions which are not really lvalues
4439 but which we can accept as lvalues.
4441 If ARG is not a kind of expression we can handle, return
4445 unary_complex_lvalue (enum tree_code code, tree arg)
4447 /* Inside a template, making these kinds of adjustments is
4448 pointless; we are only concerned with the type of the
4450 if (processing_template_decl)
4453 /* Handle (a, b) used as an "lvalue". */
4454 if (TREE_CODE (arg) == COMPOUND_EXPR)
4456 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4457 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4458 TREE_OPERAND (arg, 0), real_result);
4461 /* Handle (a ? b : c) used as an "lvalue". */
4462 if (TREE_CODE (arg) == COND_EXPR
4463 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4464 return rationalize_conditional_expr (code, arg);
4466 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4467 if (TREE_CODE (arg) == MODIFY_EXPR
4468 || TREE_CODE (arg) == PREINCREMENT_EXPR
4469 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4471 tree lvalue = TREE_OPERAND (arg, 0);
4472 if (TREE_SIDE_EFFECTS (lvalue))
4474 lvalue = stabilize_reference (lvalue);
4475 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4476 lvalue, TREE_OPERAND (arg, 1));
4478 return unary_complex_lvalue
4479 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4482 if (code != ADDR_EXPR)
4485 /* Handle (a = b) used as an "lvalue" for `&'. */
4486 if (TREE_CODE (arg) == MODIFY_EXPR
4487 || TREE_CODE (arg) == INIT_EXPR)
4489 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4490 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4492 TREE_NO_WARNING (arg) = 1;
4496 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4497 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4498 || TREE_CODE (arg) == OFFSET_REF)
4501 /* We permit compiler to make function calls returning
4502 objects of aggregate type look like lvalues. */
4506 if (TREE_CODE (targ) == SAVE_EXPR)
4507 targ = TREE_OPERAND (targ, 0);
4509 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4511 if (TREE_CODE (arg) == SAVE_EXPR)
4514 targ = build_cplus_new (TREE_TYPE (arg), arg);
4515 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4518 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4519 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4520 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4523 /* Don't let anything else be handled specially. */
4527 /* Mark EXP saying that we need to be able to take the
4528 address of it; it should not be allocated in a register.
4529 Value is true if successful.
4531 C++: we do not allow `current_class_ptr' to be addressable. */
4534 cxx_mark_addressable (tree exp)
4539 switch (TREE_CODE (x))
4546 x = TREE_OPERAND (x, 0);
4550 if (x == current_class_ptr)
4552 error ("cannot take the address of %<this%>, which is an rvalue expression");
4553 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4559 /* Caller should not be trying to mark initialized
4560 constant fields addressable. */
4561 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4562 || DECL_IN_AGGR_P (x) == 0
4564 || DECL_EXTERNAL (x));
4569 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4570 && !DECL_ARTIFICIAL (x))
4572 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4575 ("address of explicit register variable %qD requested", x);
4578 else if (extra_warnings)
4580 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
4582 TREE_ADDRESSABLE (x) = 1;
4586 TREE_ADDRESSABLE (x) = 1;
4590 TREE_ADDRESSABLE (x) = 1;
4594 TREE_ADDRESSABLE (x) = 1;
4595 cxx_mark_addressable (TREE_OPERAND (x, 0));
4603 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4606 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4608 tree orig_ifexp = ifexp;
4609 tree orig_op1 = op1;
4610 tree orig_op2 = op2;
4613 if (processing_template_decl)
4615 /* The standard says that the expression is type-dependent if
4616 IFEXP is type-dependent, even though the eventual type of the
4617 expression doesn't dependent on IFEXP. */
4618 if (type_dependent_expression_p (ifexp)
4619 /* As a GNU extension, the middle operand may be omitted. */
4620 || (op1 && type_dependent_expression_p (op1))
4621 || type_dependent_expression_p (op2))
4622 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4623 ifexp = build_non_dependent_expr (ifexp);
4625 op1 = build_non_dependent_expr (op1);
4626 op2 = build_non_dependent_expr (op2);
4629 expr = build_conditional_expr (ifexp, op1, op2);
4630 if (processing_template_decl && expr != error_mark_node)
4631 return build_min_non_dep (COND_EXPR, expr,
4632 orig_ifexp, orig_op1, orig_op2);
4636 /* Given a list of expressions, return a compound expression
4637 that performs them all and returns the value of the last of them. */
4639 tree build_x_compound_expr_from_list (tree list, const char *msg)
4641 tree expr = TREE_VALUE (list);
4643 if (TREE_CHAIN (list))
4646 pedwarn ("%s expression list treated as compound expression", msg);
4648 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4649 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4655 /* Handle overloading of the ',' operator when needed. */
4658 build_x_compound_expr (tree op1, tree op2)
4661 tree orig_op1 = op1;
4662 tree orig_op2 = op2;
4664 if (processing_template_decl)
4666 if (type_dependent_expression_p (op1)
4667 || type_dependent_expression_p (op2))
4668 return build_min_nt (COMPOUND_EXPR, op1, op2);
4669 op1 = build_non_dependent_expr (op1);
4670 op2 = build_non_dependent_expr (op2);
4673 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4674 /*overloaded_p=*/NULL);
4676 result = build_compound_expr (op1, op2);
4678 if (processing_template_decl && result != error_mark_node)
4679 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4684 /* Build a compound expression. */
4687 build_compound_expr (tree lhs, tree rhs)
4689 lhs = convert_to_void (lhs, "left-hand operand of comma");
4691 if (lhs == error_mark_node || rhs == error_mark_node)
4692 return error_mark_node;
4694 if (TREE_CODE (rhs) == TARGET_EXPR)
4696 /* If the rhs is a TARGET_EXPR, then build the compound
4697 expression inside the target_expr's initializer. This
4698 helps the compiler to eliminate unnecessary temporaries. */
4699 tree init = TREE_OPERAND (rhs, 1);
4701 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4702 TREE_OPERAND (rhs, 1) = init;
4707 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4710 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
4711 casts away constness. DIAG_FN gives the function to call if we
4712 need to issue a diagnostic; if it is NULL, no diagnostic will be
4713 issued. DESCRIPTION explains what operation is taking place. */
4716 check_for_casting_away_constness (tree src_type, tree dest_type,
4717 void (*diag_fn)(const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2),
4718 const char *description)
4720 if (diag_fn && casts_away_constness (src_type, dest_type))
4721 diag_fn ("%s from type %qT to type %qT casts away constness",
4722 description, src_type, dest_type);
4725 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
4726 (another pointer-to-member type in the same hierarchy) and return
4727 the converted expression. If ALLOW_INVERSE_P is permitted, a
4728 pointer-to-derived may be converted to pointer-to-base; otherwise,
4729 only the other direction is permitted. If C_CAST_P is true, this
4730 conversion is taking place as part of a C-style cast. */
4733 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
4736 if (TYPE_PTRMEM_P (type))
4740 if (TREE_CODE (expr) == PTRMEM_CST)
4741 expr = cplus_expand_constant (expr);
4742 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
4743 TYPE_PTRMEM_CLASS_TYPE (type),
4746 if (!integer_zerop (delta))
4747 expr = cp_build_binary_op (PLUS_EXPR,
4748 build_nop (ptrdiff_type_node, expr),
4750 return build_nop (type, expr);
4753 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4754 allow_inverse_p, c_cast_p);
4757 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
4758 a version of EXPR that has TREE_OVERFLOW and/or TREE_CONSTANT_OVERFLOW
4759 set iff they are set in ORIG. Otherwise, return EXPR unchanged. */
4762 ignore_overflows (tree expr, tree orig)
4764 if (TREE_CODE (expr) == INTEGER_CST
4765 && CONSTANT_CLASS_P (orig)
4766 && TREE_CODE (orig) != STRING_CST
4767 && (TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig)
4768 || TREE_CONSTANT_OVERFLOW (expr)
4769 != TREE_CONSTANT_OVERFLOW (orig)))
4771 if (!TREE_OVERFLOW (orig) && !TREE_CONSTANT_OVERFLOW (orig))
4772 /* Ensure constant sharing. */
4773 expr = build_int_cst_wide (TREE_TYPE (expr),
4774 TREE_INT_CST_LOW (expr),
4775 TREE_INT_CST_HIGH (expr));
4778 /* Avoid clobbering a shared constant. */
4779 expr = copy_node (expr);
4780 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
4781 TREE_CONSTANT_OVERFLOW (expr)
4782 = TREE_CONSTANT_OVERFLOW (orig);
4788 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
4789 this static_cast is being attempted as one of the possible casts
4790 allowed by a C-style cast. (In that case, accessibility of base
4791 classes is not considered, and it is OK to cast away
4792 constness.) Return the result of the cast. *VALID_P is set to
4793 indicate whether or not the cast was valid. */
4796 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
4802 void (*diag_fn)(const char*, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
4805 /* Assume the cast is valid. */
4808 intype = TREE_TYPE (expr);
4810 /* Save casted types in the function's used types hash table. */
4811 used_types_insert (type);
4813 /* Determine what to do when casting away constness. */
4816 /* C-style casts are allowed to cast away constness. With
4817 WARN_CAST_QUAL, we still want to issue a warning. */
4818 diag_fn = warn_cast_qual ? warning0 : NULL;
4823 /* A static_cast may not cast away constness. */
4825 desc = "static_cast";
4828 /* [expr.static.cast]
4830 An lvalue of type "cv1 B", where B is a class type, can be cast
4831 to type "reference to cv2 D", where D is a class derived (clause
4832 _class.derived_) from B, if a valid standard conversion from
4833 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4834 same cv-qualification as, or greater cv-qualification than, cv1,
4835 and B is not a virtual base class of D. */
4836 /* We check this case before checking the validity of "TYPE t =
4837 EXPR;" below because for this case:
4840 struct D : public B { D(const B&); };
4842 void f() { static_cast<const D&>(b); }
4844 we want to avoid constructing a new D. The standard is not
4845 completely clear about this issue, but our interpretation is
4846 consistent with other compilers. */
4847 if (TREE_CODE (type) == REFERENCE_TYPE
4848 && CLASS_TYPE_P (TREE_TYPE (type))
4849 && CLASS_TYPE_P (intype)
4850 && real_lvalue_p (expr)
4851 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4852 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4853 build_pointer_type (TYPE_MAIN_VARIANT
4854 (TREE_TYPE (type))))
4856 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
4860 /* There is a standard conversion from "D*" to "B*" even if "B"
4861 is ambiguous or inaccessible. If this is really a
4862 static_cast, then we check both for inaccessibility and
4863 ambiguity. However, if this is a static_cast being performed
4864 because the user wrote a C-style cast, then accessibility is
4866 base = lookup_base (TREE_TYPE (type), intype,
4867 c_cast_p ? ba_unique : ba_check,
4870 /* Convert from "B*" to "D*". This function will check that "B"
4871 is not a virtual base of "D". */
4872 expr = build_base_path (MINUS_EXPR, build_address (expr),
4873 base, /*nonnull=*/false);
4874 /* Convert the pointer to a reference -- but then remember that
4875 there are no expressions with reference type in C++. */
4876 return convert_from_reference (build_nop (type, expr));
4881 /* [expr.static.cast]
4883 An expression e can be explicitly converted to a type T using a
4884 static_cast of the form static_cast<T>(e) if the declaration T
4885 t(e);" is well-formed, for some invented temporary variable
4887 result = perform_direct_initialization_if_possible (type, expr,
4891 result = convert_from_reference (result);
4893 /* Ignore any integer overflow caused by the cast. */
4894 result = ignore_overflows (result, orig);
4896 /* [expr.static.cast]
4898 If T is a reference type, the result is an lvalue; otherwise,
4899 the result is an rvalue. */
4900 if (TREE_CODE (type) != REFERENCE_TYPE)
4901 result = rvalue (result);
4905 /* [expr.static.cast]
4907 Any expression can be explicitly converted to type cv void. */
4908 if (TREE_CODE (type) == VOID_TYPE)
4909 return convert_to_void (expr, /*implicit=*/NULL);
4911 /* [expr.static.cast]
4913 The inverse of any standard conversion sequence (clause _conv_),
4914 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4915 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4916 (_conv.bool_) conversions, can be performed explicitly using
4917 static_cast subject to the restriction that the explicit
4918 conversion does not cast away constness (_expr.const.cast_), and
4919 the following additional rules for specific cases: */
4920 /* For reference, the conversions not excluded are: integral
4921 promotions, floating point promotion, integral conversions,
4922 floating point conversions, floating-integral conversions,
4923 pointer conversions, and pointer to member conversions. */
4926 A value of integral _or enumeration_ type can be explicitly
4927 converted to an enumeration type. */
4928 /* The effect of all that is that any conversion between any two
4929 types which are integral, floating, or enumeration types can be
4931 if ((INTEGRAL_TYPE_P (type) || SCALAR_FLOAT_TYPE_P (type))
4932 && (INTEGRAL_TYPE_P (intype) || SCALAR_FLOAT_TYPE_P (intype)))
4934 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
4936 /* Ignore any integer overflow caused by the cast. */
4937 expr = ignore_overflows (expr, orig);
4941 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4942 && CLASS_TYPE_P (TREE_TYPE (type))
4943 && CLASS_TYPE_P (TREE_TYPE (intype))
4944 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4945 (TREE_TYPE (intype))),
4946 build_pointer_type (TYPE_MAIN_VARIANT
4947 (TREE_TYPE (type)))))
4952 check_for_casting_away_constness (intype, type, diag_fn, desc);
4953 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
4954 c_cast_p ? ba_unique : ba_check,
4956 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4959 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4960 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4967 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4968 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4970 if (TYPE_PTRMEM_P (type))
4972 t1 = (build_ptrmem_type
4974 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4975 t2 = (build_ptrmem_type
4977 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4984 if (can_convert (t1, t2))
4987 check_for_casting_away_constness (intype, type, diag_fn,
4989 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
4994 /* [expr.static.cast]
4996 An rvalue of type "pointer to cv void" can be explicitly
4997 converted to a pointer to object type. A value of type pointer
4998 to object converted to "pointer to cv void" and back to the
4999 original pointer type will have its original value. */
5000 if (TREE_CODE (intype) == POINTER_TYPE
5001 && VOID_TYPE_P (TREE_TYPE (intype))
5002 && TYPE_PTROB_P (type))
5005 check_for_casting_away_constness (intype, type, diag_fn, desc);
5006 return build_nop (type, expr);
5010 return error_mark_node;
5013 /* Return an expression representing static_cast<TYPE>(EXPR). */
5016 build_static_cast (tree type, tree expr)
5021 if (type == error_mark_node || expr == error_mark_node)
5022 return error_mark_node;
5024 if (processing_template_decl)
5026 expr = build_min (STATIC_CAST_EXPR, type, expr);
5027 /* We don't know if it will or will not have side effects. */
5028 TREE_SIDE_EFFECTS (expr) = 1;
5029 return convert_from_reference (expr);
5032 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5033 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5034 if (TREE_CODE (type) != REFERENCE_TYPE
5035 && TREE_CODE (expr) == NOP_EXPR
5036 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5037 expr = TREE_OPERAND (expr, 0);
5039 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p);
5043 error ("invalid static_cast from type %qT to type %qT",
5044 TREE_TYPE (expr), type);
5045 return error_mark_node;
5048 /* EXPR is an expression with member function or pointer-to-member
5049 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5050 not permitted by ISO C++, but we accept it in some modes. If we
5051 are not in one of those modes, issue a diagnostic. Return the
5052 converted expression. */
5055 convert_member_func_to_ptr (tree type, tree expr)
5060 intype = TREE_TYPE (expr);
5061 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
5062 || TREE_CODE (intype) == METHOD_TYPE);
5064 if (pedantic || warn_pmf2ptr)
5065 pedwarn ("converting from %qT to %qT", intype, type);
5067 if (TREE_CODE (intype) == METHOD_TYPE)
5068 expr = build_addr_func (expr);
5069 else if (TREE_CODE (expr) == PTRMEM_CST)
5070 expr = build_address (PTRMEM_CST_MEMBER (expr));
5073 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
5074 decl = build_address (decl);
5075 expr = get_member_function_from_ptrfunc (&decl, expr);
5078 return build_nop (type, expr);
5081 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5082 If C_CAST_P is true, this reinterpret cast is being done as part of
5083 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5084 indicate whether or not reinterpret_cast was valid. */
5087 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5092 /* Assume the cast is invalid. */
5096 if (type == error_mark_node || error_operand_p (expr))
5097 return error_mark_node;
5099 intype = TREE_TYPE (expr);
5101 /* Save casted types in the function's used types hash table. */
5102 used_types_insert (type);
5104 /* [expr.reinterpret.cast]
5105 An lvalue expression of type T1 can be cast to the type
5106 "reference to T2" if an expression of type "pointer to T1" can be
5107 explicitly converted to the type "pointer to T2" using a
5108 reinterpret_cast. */
5109 if (TREE_CODE (type) == REFERENCE_TYPE)
5111 if (! real_lvalue_p (expr))
5113 error ("invalid cast of an rvalue expression of type "
5116 return error_mark_node;
5119 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5120 "B" are related class types; the reinterpret_cast does not
5121 adjust the pointer. */
5122 if (TYPE_PTR_P (intype)
5123 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5124 COMPARE_BASE | COMPARE_DERIVED)))
5125 warning (0, "casting %qT to %qT does not dereference pointer",
5128 expr = build_unary_op (ADDR_EXPR, expr, 0);
5129 if (expr != error_mark_node)
5130 expr = build_reinterpret_cast_1
5131 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5133 if (expr != error_mark_node)
5134 expr = build_indirect_ref (expr, 0);
5138 /* As a G++ extension, we consider conversions from member
5139 functions, and pointers to member functions to
5140 pointer-to-function and pointer-to-void types. If
5141 -Wno-pmf-conversions has not been specified,
5142 convert_member_func_to_ptr will issue an error message. */
5143 if ((TYPE_PTRMEMFUNC_P (intype)
5144 || TREE_CODE (intype) == METHOD_TYPE)
5145 && TYPE_PTR_P (type)
5146 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5147 || VOID_TYPE_P (TREE_TYPE (type))))
5148 return convert_member_func_to_ptr (type, expr);
5150 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5151 array-to-pointer, and function-to-pointer conversions are
5153 expr = decay_conversion (expr);
5155 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5156 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5157 if (TREE_CODE (expr) == NOP_EXPR
5158 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5159 expr = TREE_OPERAND (expr, 0);
5161 if (error_operand_p (expr))
5162 return error_mark_node;
5164 intype = TREE_TYPE (expr);
5166 /* [expr.reinterpret.cast]
5167 A pointer can be converted to any integral type large enough to
5169 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5171 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5172 pedwarn ("cast from %qT to %qT loses precision",
5175 /* [expr.reinterpret.cast]
5176 A value of integral or enumeration type can be explicitly
5177 converted to a pointer. */
5178 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5181 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5182 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5183 return fold_if_not_in_template (build_nop (type, expr));
5184 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5185 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5190 check_for_casting_away_constness (intype, type, error,
5191 "reinterpret_cast");
5192 /* Warn about possible alignment problems. */
5193 if (STRICT_ALIGNMENT && warn_cast_align
5194 && !VOID_TYPE_P (type)
5195 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5196 && COMPLETE_TYPE_P (TREE_TYPE (type))
5197 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5198 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5199 warning (0, "cast from %qT to %qT increases required alignment of "
5203 /* We need to strip nops here, because the frontend likes to
5204 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5206 strict_aliasing_warning (intype, type, sexpr);
5208 return fold_if_not_in_template (build_nop (type, expr));
5210 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5211 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5214 /* Only issue a warning, as we have always supported this
5215 where possible, and it is necessary in some cases. DR 195
5216 addresses this issue, but as of 2004/10/26 is still in
5218 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5219 return fold_if_not_in_template (build_nop (type, expr));
5221 else if (TREE_CODE (type) == VECTOR_TYPE)
5222 return fold_if_not_in_template (convert_to_vector (type, expr));
5223 else if (TREE_CODE (intype) == VECTOR_TYPE)
5224 return fold_if_not_in_template (convert_to_integer (type, expr));
5229 error ("invalid cast from type %qT to type %qT", intype, type);
5230 return error_mark_node;
5233 return cp_convert (type, expr);
5237 build_reinterpret_cast (tree type, tree expr)
5239 if (type == error_mark_node || expr == error_mark_node)
5240 return error_mark_node;
5242 if (processing_template_decl)
5244 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5246 if (!TREE_SIDE_EFFECTS (t)
5247 && type_dependent_expression_p (expr))
5248 /* There might turn out to be side effects inside expr. */
5249 TREE_SIDE_EFFECTS (t) = 1;
5250 return convert_from_reference (t);
5253 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5257 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5258 return an appropriate expression. Otherwise, return
5259 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5260 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5261 performing a C-style cast, its value upon return will indicate
5262 whether or not the conversion succeeded. */
5265 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5269 tree reference_type;
5271 /* Callers are responsible for handling error_mark_node as a
5272 destination type. */
5273 gcc_assert (dst_type != error_mark_node);
5274 /* In a template, callers should be building syntactic
5275 representations of casts, not using this machinery. */
5276 gcc_assert (!processing_template_decl);
5278 /* Assume the conversion is invalid. */
5282 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5285 error ("invalid use of const_cast with type %qT, "
5286 "which is not a pointer, "
5287 "reference, nor a pointer-to-data-member type", dst_type);
5288 return error_mark_node;
5291 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5294 error ("invalid use of const_cast with type %qT, which is a pointer "
5295 "or reference to a function type", dst_type);
5296 return error_mark_node;
5299 /* Save casted types in the function's used types hash table. */
5300 used_types_insert (dst_type);
5302 src_type = TREE_TYPE (expr);
5303 /* Expressions do not really have reference types. */
5304 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5305 src_type = TREE_TYPE (src_type);
5307 /* [expr.const.cast]
5309 An lvalue of type T1 can be explicitly converted to an lvalue of
5310 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5311 types) if a pointer to T1 can be explicitly converted to the type
5312 pointer to T2 using a const_cast. */
5313 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5315 reference_type = dst_type;
5316 if (! real_lvalue_p (expr))
5319 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5320 src_type, dst_type);
5321 return error_mark_node;
5323 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5324 src_type = build_pointer_type (src_type);
5328 reference_type = NULL_TREE;
5329 /* If the destination type is not a reference type, the
5330 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5331 conversions are performed. */
5332 src_type = type_decays_to (src_type);
5333 if (src_type == error_mark_node)
5334 return error_mark_node;
5337 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5338 && comp_ptr_ttypes_const (dst_type, src_type))
5343 /* This cast is actually a C-style cast. Issue a warning if
5344 the user is making a potentially unsafe cast. */
5346 check_for_casting_away_constness (src_type, dst_type,
5352 expr = build_unary_op (ADDR_EXPR, expr, 0);
5353 expr = build_nop (reference_type, expr);
5354 return convert_from_reference (expr);
5358 expr = decay_conversion (expr);
5359 /* build_c_cast puts on a NOP_EXPR to make the result not an
5360 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5361 non-lvalue context. */
5362 if (TREE_CODE (expr) == NOP_EXPR
5363 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5364 expr = TREE_OPERAND (expr, 0);
5365 return build_nop (dst_type, expr);
5370 error ("invalid const_cast from type %qT to type %qT",
5371 src_type, dst_type);
5372 return error_mark_node;
5376 build_const_cast (tree type, tree expr)
5378 if (type == error_mark_node || error_operand_p (expr))
5379 return error_mark_node;
5381 if (processing_template_decl)
5383 tree t = build_min (CONST_CAST_EXPR, type, expr);
5385 if (!TREE_SIDE_EFFECTS (t)
5386 && type_dependent_expression_p (expr))
5387 /* There might turn out to be side effects inside expr. */
5388 TREE_SIDE_EFFECTS (t) = 1;
5389 return convert_from_reference (t);
5392 return build_const_cast_1 (type, expr, /*complain=*/true,
5396 /* Build an expression representing an explicit C-style cast to type
5397 TYPE of expression EXPR. */
5400 build_c_cast (tree type, tree expr)
5406 if (type == error_mark_node || error_operand_p (expr))
5407 return error_mark_node;
5409 if (processing_template_decl)
5411 tree t = build_min (CAST_EXPR, type,
5412 tree_cons (NULL_TREE, value, NULL_TREE));
5413 /* We don't know if it will or will not have side effects. */
5414 TREE_SIDE_EFFECTS (t) = 1;
5415 return convert_from_reference (t);
5418 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5419 'Class') should always be retained, because this information aids
5420 in method lookup. */
5421 if (objc_is_object_ptr (type)
5422 && objc_is_object_ptr (TREE_TYPE (expr)))
5423 return build_nop (type, expr);
5425 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5426 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5427 if (TREE_CODE (type) != REFERENCE_TYPE
5428 && TREE_CODE (value) == NOP_EXPR
5429 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5430 value = TREE_OPERAND (value, 0);
5432 if (TREE_CODE (type) == ARRAY_TYPE)
5434 /* Allow casting from T1* to T2[] because Cfront allows it.
5435 NIHCL uses it. It is not valid ISO C++ however. */
5436 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5438 pedwarn ("ISO C++ forbids casting to an array type %qT", type);
5439 type = build_pointer_type (TREE_TYPE (type));
5443 error ("ISO C++ forbids casting to an array type %qT", type);
5444 return error_mark_node;
5448 if (TREE_CODE (type) == FUNCTION_TYPE
5449 || TREE_CODE (type) == METHOD_TYPE)
5451 error ("invalid cast to function type %qT", type);
5452 return error_mark_node;
5455 /* A C-style cast can be a const_cast. */
5456 result = build_const_cast_1 (type, value, /*complain=*/false,
5461 /* Or a static cast. */
5462 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5464 /* Or a reinterpret_cast. */
5466 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5468 /* The static_cast or reinterpret_cast may be followed by a
5471 /* A valid cast may result in errors if, for example, a
5472 conversion to am ambiguous base class is required. */
5473 && !error_operand_p (result))
5477 /* Non-class rvalues always have cv-unqualified type. */
5478 if (!CLASS_TYPE_P (type))
5479 type = TYPE_MAIN_VARIANT (type);
5480 result_type = TREE_TYPE (result);
5481 if (!CLASS_TYPE_P (result_type))
5482 result_type = TYPE_MAIN_VARIANT (result_type);
5483 /* If the type of RESULT does not match TYPE, perform a
5484 const_cast to make it match. If the static_cast or
5485 reinterpret_cast succeeded, we will differ by at most
5486 cv-qualification, so the follow-on const_cast is guaranteed
5488 if (!same_type_p (non_reference (type), non_reference (result_type)))
5490 result = build_const_cast_1 (type, result, false, &valid_p);
5491 gcc_assert (valid_p);
5496 return error_mark_node;
5499 /* Build an assignment expression of lvalue LHS from value RHS.
5500 MODIFYCODE is the code for a binary operator that we use
5501 to combine the old value of LHS with RHS to get the new value.
5502 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5504 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5507 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5511 tree lhstype = TREE_TYPE (lhs);
5512 tree olhstype = lhstype;
5513 tree olhs = NULL_TREE;
5514 bool plain_assign = (modifycode == NOP_EXPR);
5516 /* Avoid duplicate error messages from operands that had errors. */
5517 if (error_operand_p (lhs) || error_operand_p (rhs))
5518 return error_mark_node;
5520 /* Handle control structure constructs used as "lvalues". */
5521 switch (TREE_CODE (lhs))
5523 /* Handle --foo = 5; as these are valid constructs in C++. */
5524 case PREDECREMENT_EXPR:
5525 case PREINCREMENT_EXPR:
5526 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5527 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5528 stabilize_reference (TREE_OPERAND (lhs, 0)),
5529 TREE_OPERAND (lhs, 1));
5530 return build2 (COMPOUND_EXPR, lhstype,
5532 build_modify_expr (TREE_OPERAND (lhs, 0),
5535 /* Handle (a, b) used as an "lvalue". */
5537 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
5539 if (newrhs == error_mark_node)
5540 return error_mark_node;
5541 return build2 (COMPOUND_EXPR, lhstype,
5542 TREE_OPERAND (lhs, 0), newrhs);
5545 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5546 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5547 stabilize_reference (TREE_OPERAND (lhs, 0)),
5548 TREE_OPERAND (lhs, 1));
5549 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
5550 if (newrhs == error_mark_node)
5551 return error_mark_node;
5552 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5556 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
5557 when neither operand has side-effects. */
5558 if (!lvalue_or_else (lhs, lv_assign))
5559 return error_mark_node;
5561 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
5562 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
5564 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
5565 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
5567 TREE_OPERAND (lhs, 0),
5568 TREE_OPERAND (lhs, 1)),
5569 TREE_OPERAND (lhs, 0),
5570 TREE_OPERAND (lhs, 1));
5573 /* Handle (a ? b : c) used as an "lvalue". */
5576 /* Produce (a ? (b = rhs) : (c = rhs))
5577 except that the RHS goes through a save-expr
5578 so the code to compute it is only emitted once. */
5580 tree preeval = NULL_TREE;
5582 rhs = stabilize_expr (rhs, &preeval);
5584 /* Check this here to avoid odd errors when trying to convert
5585 a throw to the type of the COND_EXPR. */
5586 if (!lvalue_or_else (lhs, lv_assign))
5587 return error_mark_node;
5589 cond = build_conditional_expr
5590 (TREE_OPERAND (lhs, 0),
5591 build_modify_expr (TREE_OPERAND (lhs, 1),
5593 build_modify_expr (TREE_OPERAND (lhs, 2),
5596 if (cond == error_mark_node)
5598 /* Make sure the code to compute the rhs comes out
5599 before the split. */
5601 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5609 if (modifycode == INIT_EXPR)
5611 if (TREE_CODE (rhs) == CONSTRUCTOR)
5613 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5614 /* Call convert to generate an error; see PR 11063. */
5615 rhs = convert (lhstype, rhs);
5616 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
5617 TREE_SIDE_EFFECTS (result) = 1;
5620 else if (! IS_AGGR_TYPE (lhstype))
5621 /* Do the default thing. */;
5624 result = build_special_member_call (lhs, complete_ctor_identifier,
5625 build_tree_list (NULL_TREE, rhs),
5626 lhstype, LOOKUP_NORMAL);
5627 if (result == NULL_TREE)
5628 return error_mark_node;
5634 lhs = require_complete_type (lhs);
5635 if (lhs == error_mark_node)
5636 return error_mark_node;
5638 if (modifycode == NOP_EXPR)
5640 /* `operator=' is not an inheritable operator. */
5641 if (! IS_AGGR_TYPE (lhstype))
5642 /* Do the default thing. */;
5645 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5646 lhs, rhs, make_node (NOP_EXPR),
5647 /*overloaded_p=*/NULL);
5648 if (result == NULL_TREE)
5649 return error_mark_node;
5656 /* A binary op has been requested. Combine the old LHS
5657 value with the RHS producing the value we should actually
5658 store into the LHS. */
5660 gcc_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE));
5661 lhs = stabilize_reference (lhs);
5662 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
5663 if (newrhs == error_mark_node)
5665 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
5666 TREE_TYPE (lhs), TREE_TYPE (rhs));
5667 return error_mark_node;
5670 /* Now it looks like a plain assignment. */
5671 modifycode = NOP_EXPR;
5673 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
5674 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
5677 /* The left-hand side must be an lvalue. */
5678 if (!lvalue_or_else (lhs, lv_assign))
5679 return error_mark_node;
5681 /* Warn about modifying something that is `const'. Don't warn if
5682 this is initialization. */
5683 if (modifycode != INIT_EXPR
5684 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5685 /* Functions are not modifiable, even though they are
5687 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5688 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5689 /* If it's an aggregate and any field is const, then it is
5690 effectively const. */
5691 || (CLASS_TYPE_P (lhstype)
5692 && C_TYPE_FIELDS_READONLY (lhstype))))
5693 readonly_error (lhs, "assignment", 0);
5695 /* If storing into a structure or union member, it has probably been
5696 given type `int'. Compute the type that would go with the actual
5697 amount of storage the member occupies. */
5699 if (TREE_CODE (lhs) == COMPONENT_REF
5700 && (TREE_CODE (lhstype) == INTEGER_TYPE
5701 || TREE_CODE (lhstype) == REAL_TYPE
5702 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5704 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5706 /* If storing in a field that is in actuality a short or narrower
5707 than one, we must store in the field in its actual type. */
5709 if (lhstype != TREE_TYPE (lhs))
5711 /* Avoid warnings converting integral types back into enums for
5713 if (TREE_CODE (lhstype) == INTEGER_TYPE
5714 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5716 if (TREE_SIDE_EFFECTS (lhs))
5717 lhs = stabilize_reference (lhs);
5720 lhs = copy_node (lhs);
5721 TREE_TYPE (lhs) = lhstype;
5725 /* Convert new value to destination type. */
5727 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5731 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5732 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5734 error ("incompatible types in assignment of %qT to %qT",
5735 TREE_TYPE (rhs), lhstype);
5736 return error_mark_node;
5739 /* Allow array assignment in compiler-generated code. */
5740 if (! DECL_ARTIFICIAL (current_function_decl))
5742 /* This routine is used for both initialization and assignment.
5743 Make sure the diagnostic message differentiates the context. */
5744 if (modifycode == INIT_EXPR)
5745 error ("array used as initializer");
5747 error ("invalid array assignment");
5748 return error_mark_node;
5751 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5752 ? 1 + (modifycode != INIT_EXPR): 0;
5753 return build_vec_init (lhs, NULL_TREE, newrhs,
5754 /*explicit_default_init_p=*/false,
5758 if (modifycode == INIT_EXPR)
5759 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5760 "initialization", NULL_TREE, 0);
5763 /* Avoid warnings on enum bit fields. */
5764 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5765 && TREE_CODE (lhstype) == INTEGER_TYPE)
5767 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5769 newrhs = convert_force (lhstype, newrhs, 0);
5772 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5774 if (TREE_CODE (newrhs) == CALL_EXPR
5775 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5776 newrhs = build_cplus_new (lhstype, newrhs);
5778 /* Can't initialize directly from a TARGET_EXPR, since that would
5779 cause the lhs to be constructed twice, and possibly result in
5780 accidental self-initialization. So we force the TARGET_EXPR to be
5781 expanded without a target. */
5782 if (TREE_CODE (newrhs) == TARGET_EXPR)
5783 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5784 TREE_OPERAND (newrhs, 0));
5787 if (newrhs == error_mark_node)
5788 return error_mark_node;
5790 if (c_dialect_objc () && flag_objc_gc)
5792 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
5798 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5799 lhstype, lhs, newrhs);
5801 TREE_SIDE_EFFECTS (result) = 1;
5803 TREE_NO_WARNING (result) = 1;
5805 /* If we got the LHS in a different type for storing in,
5806 convert the result back to the nominal type of LHS
5807 so that the value we return always has the same type
5808 as the LHS argument. */
5810 if (olhstype == TREE_TYPE (result))
5814 result = build2 (COMPOUND_EXPR, olhstype, result, olhs);
5815 TREE_NO_WARNING (result) = 1;
5818 return convert_for_assignment (olhstype, result, "assignment",
5823 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5825 if (processing_template_decl)
5826 return build_min_nt (MODOP_EXPR, lhs,
5827 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5829 if (modifycode != NOP_EXPR)
5831 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5832 make_node (modifycode),
5833 /*overloaded_p=*/NULL);
5836 TREE_NO_WARNING (rval) = 1;
5840 return build_modify_expr (lhs, modifycode, rhs);
5844 /* Get difference in deltas for different pointer to member function
5845 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5846 the conversion is invalid, the constant is zero. If
5847 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
5848 If C_CAST_P is true this conversion is taking place as part of a
5851 Note that the naming of FROM and TO is kind of backwards; the return
5852 value is what we add to a TO in order to get a FROM. They are named
5853 this way because we call this function to find out how to convert from
5854 a pointer to member of FROM to a pointer to member of TO. */
5857 get_delta_difference (tree from, tree to,
5858 bool allow_inverse_p,
5865 /* Assume no conversion is required. */
5866 result = integer_zero_node;
5867 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
5868 if (kind == bk_inaccessible || kind == bk_ambig)
5869 error (" in pointer to member function conversion");
5872 if (kind != bk_via_virtual)
5873 result = BINFO_OFFSET (binfo);
5876 tree virt_binfo = binfo_from_vbase (binfo);
5878 /* This is a reinterpret cast, we choose to do nothing. */
5879 if (allow_inverse_p)
5880 warning (0, "pointer to member cast via virtual base %qT",
5881 BINFO_TYPE (virt_binfo));
5883 error ("pointer to member conversion via virtual base %qT",
5884 BINFO_TYPE (virt_binfo));
5887 else if (same_type_ignoring_top_level_qualifiers_p (from, to))
5888 /* Pointer to member of incomplete class is permitted*/;
5889 else if (!allow_inverse_p)
5891 error_not_base_type (from, to);
5892 error (" in pointer to member conversion");
5896 binfo = lookup_base (from, to, c_cast_p ? ba_unique : ba_check, &kind);
5899 if (kind != bk_via_virtual)
5900 result = size_diffop (size_zero_node, BINFO_OFFSET (binfo));
5903 /* This is a reinterpret cast, we choose to do nothing. */
5904 tree virt_binfo = binfo_from_vbase (binfo);
5906 warning (0, "pointer to member cast via virtual base %qT",
5907 BINFO_TYPE (virt_binfo));
5912 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
5916 /* Return a constructor for the pointer-to-member-function TYPE using
5917 the other components as specified. */
5920 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5925 VEC(constructor_elt, gc) *v;
5927 /* Pull the FIELD_DECLs out of the type. */
5928 pfn_field = TYPE_FIELDS (type);
5929 delta_field = TREE_CHAIN (pfn_field);
5931 /* Make sure DELTA has the type we want. */
5932 delta = convert_and_check (delta_type_node, delta);
5934 /* Finish creating the initializer. */
5935 v = VEC_alloc(constructor_elt, gc, 2);
5936 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
5937 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
5938 u = build_constructor (type, v);
5939 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
5940 TREE_INVARIANT (u) = TREE_INVARIANT (pfn) & TREE_INVARIANT (delta);
5941 TREE_STATIC (u) = (TREE_CONSTANT (u)
5942 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5944 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5949 /* Build a constructor for a pointer to member function. It can be
5950 used to initialize global variables, local variable, or used
5951 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5954 If FORCE is nonzero, then force this conversion, even if
5955 we would rather not do it. Usually set when using an explicit
5956 cast. A C-style cast is being processed iff C_CAST_P is true.
5958 Return error_mark_node, if something goes wrong. */
5961 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
5967 if (error_operand_p (pfn))
5968 return error_mark_node;
5970 pfn_type = TREE_TYPE (pfn);
5971 to_type = build_ptrmemfunc_type (type);
5973 /* Handle multiple conversions of pointer to member functions. */
5974 if (TYPE_PTRMEMFUNC_P (pfn_type))
5976 tree delta = NULL_TREE;
5977 tree npfn = NULL_TREE;
5981 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
5982 error ("invalid conversion to type %qT from type %qT",
5985 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5986 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5990 /* We don't have to do any conversion to convert a
5991 pointer-to-member to its own type. But, we don't want to
5992 just return a PTRMEM_CST if there's an explicit cast; that
5993 cast should make the expression an invalid template argument. */
5994 if (TREE_CODE (pfn) != PTRMEM_CST)
5996 if (same_type_p (to_type, pfn_type))
5998 else if (integer_zerop (n))
5999 return build_reinterpret_cast (to_type, pfn);
6002 if (TREE_SIDE_EFFECTS (pfn))
6003 pfn = save_expr (pfn);
6005 /* Obtain the function pointer and the current DELTA. */
6006 if (TREE_CODE (pfn) == PTRMEM_CST)
6007 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
6010 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
6011 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
6014 /* Just adjust the DELTA field. */
6015 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6016 (TREE_TYPE (delta), ptrdiff_type_node));
6017 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
6018 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
6019 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
6020 return build_ptrmemfunc1 (to_type, delta, npfn);
6023 /* Handle null pointer to member function conversions. */
6024 if (integer_zerop (pfn))
6026 pfn = build_c_cast (type, integer_zero_node);
6027 return build_ptrmemfunc1 (to_type,
6032 if (type_unknown_p (pfn))
6033 return instantiate_type (type, pfn, tf_warning_or_error);
6035 fn = TREE_OPERAND (pfn, 0);
6036 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
6037 /* In a template, we will have preserved the
6039 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
6040 return make_ptrmem_cst (to_type, fn);
6043 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
6046 ??? There is no consistency as to the types returned for the above
6047 values. Some code acts as if it were a sizetype and some as if it were
6048 integer_type_node. */
6051 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
6053 tree type = TREE_TYPE (cst);
6054 tree fn = PTRMEM_CST_MEMBER (cst);
6055 tree ptr_class, fn_class;
6057 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6059 /* The class that the function belongs to. */
6060 fn_class = DECL_CONTEXT (fn);
6062 /* The class that we're creating a pointer to member of. */
6063 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
6065 /* First, calculate the adjustment to the function's class. */
6066 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
6069 if (!DECL_VIRTUAL_P (fn))
6070 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
6073 /* If we're dealing with a virtual function, we have to adjust 'this'
6074 again, to point to the base which provides the vtable entry for
6075 fn; the call will do the opposite adjustment. */
6076 tree orig_class = DECL_CONTEXT (fn);
6077 tree binfo = binfo_or_else (orig_class, fn_class);
6078 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6079 *delta, BINFO_OFFSET (binfo));
6080 *delta = fold_if_not_in_template (*delta);
6082 /* We set PFN to the vtable offset at which the function can be
6083 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6084 case delta is shifted left, and then incremented). */
6085 *pfn = DECL_VINDEX (fn);
6086 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
6087 TYPE_SIZE_UNIT (vtable_entry_type));
6088 *pfn = fold_if_not_in_template (*pfn);
6090 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
6092 case ptrmemfunc_vbit_in_pfn:
6093 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6095 *pfn = fold_if_not_in_template (*pfn);
6098 case ptrmemfunc_vbit_in_delta:
6099 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6100 *delta, integer_one_node);
6101 *delta = fold_if_not_in_template (*delta);
6102 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6103 *delta, integer_one_node);
6104 *delta = fold_if_not_in_template (*delta);
6111 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6112 *pfn = fold_if_not_in_template (*pfn);
6116 /* Return an expression for PFN from the pointer-to-member function
6120 pfn_from_ptrmemfunc (tree t)
6122 if (TREE_CODE (t) == PTRMEM_CST)
6127 expand_ptrmemfunc_cst (t, &delta, &pfn);
6132 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6135 /* Convert value RHS to type TYPE as preparation for an assignment to
6136 an lvalue of type TYPE. ERRTYPE is a string to use in error
6137 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6138 are doing the conversion in order to pass the PARMNUMth argument of
6142 convert_for_assignment (tree type, tree rhs,
6143 const char *errtype, tree fndecl, int parmnum)
6146 enum tree_code coder;
6148 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6149 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6150 rhs = TREE_OPERAND (rhs, 0);
6152 rhstype = TREE_TYPE (rhs);
6153 coder = TREE_CODE (rhstype);
6155 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6156 && vector_types_convertible_p (type, rhstype))
6157 return convert (type, rhs);
6159 if (rhs == error_mark_node || rhstype == error_mark_node)
6160 return error_mark_node;
6161 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6162 return error_mark_node;
6164 /* The RHS of an assignment cannot have void type. */
6165 if (coder == VOID_TYPE)
6167 error ("void value not ignored as it ought to be");
6168 return error_mark_node;
6171 /* Simplify the RHS if possible. */
6172 if (TREE_CODE (rhs) == CONST_DECL)
6173 rhs = DECL_INITIAL (rhs);
6175 if (c_dialect_objc ())
6178 tree rname = fndecl;
6180 if (!strcmp (errtype, "assignment"))
6182 else if (!strcmp (errtype, "initialization"))
6186 tree selector = objc_message_selector ();
6190 if (selector && parmno > 1)
6197 if (objc_compare_types (type, rhstype, parmno, rname))
6198 return convert (type, rhs);
6203 The expression is implicitly converted (clause _conv_) to the
6204 cv-unqualified type of the left operand.
6206 We allow bad conversions here because by the time we get to this point
6207 we are committed to doing the conversion. If we end up doing a bad
6208 conversion, convert_like will complain. */
6209 if (!can_convert_arg_bad (type, rhstype, rhs))
6211 /* When -Wno-pmf-conversions is use, we just silently allow
6212 conversions from pointers-to-members to plain pointers. If
6213 the conversion doesn't work, cp_convert will complain. */
6215 && TYPE_PTR_P (type)
6216 && TYPE_PTRMEMFUNC_P (rhstype))
6217 rhs = cp_convert (strip_top_quals (type), rhs);
6220 /* If the right-hand side has unknown type, then it is an
6221 overloaded function. Call instantiate_type to get error
6223 if (rhstype == unknown_type_node)
6224 instantiate_type (type, rhs, tf_warning_or_error);
6226 error ("cannot convert %qT to %qT for argument %qP to %qD",
6227 rhstype, type, parmnum, fndecl);
6229 error ("cannot convert %qT to %qT in %s", rhstype, type, errtype);
6230 return error_mark_node;
6233 if (warn_missing_format_attribute)
6235 const enum tree_code codel = TREE_CODE (type);
6236 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6238 && check_missing_format_attribute (type, rhstype))
6239 warning (OPT_Wmissing_format_attribute,
6240 "%s might be a candidate for a format attribute",
6244 return perform_implicit_conversion (strip_top_quals (type), rhs);
6247 /* Convert RHS to be of type TYPE.
6248 If EXP is nonzero, it is the target of the initialization.
6249 ERRTYPE is a string to use in error messages.
6251 Two major differences between the behavior of
6252 `convert_for_assignment' and `convert_for_initialization'
6253 are that references are bashed in the former, while
6254 copied in the latter, and aggregates are assigned in
6255 the former (operator=) while initialized in the
6258 If using constructor make sure no conversion operator exists, if one does
6259 exist, an ambiguity exists.
6261 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6264 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6265 const char *errtype, tree fndecl, int parmnum)
6267 enum tree_code codel = TREE_CODE (type);
6269 enum tree_code coder;
6271 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6272 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6273 if (TREE_CODE (rhs) == NOP_EXPR
6274 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6275 && codel != REFERENCE_TYPE)
6276 rhs = TREE_OPERAND (rhs, 0);
6278 if (type == error_mark_node
6279 || rhs == error_mark_node
6280 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6281 return error_mark_node;
6283 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6284 && TREE_CODE (type) != ARRAY_TYPE
6285 && (TREE_CODE (type) != REFERENCE_TYPE
6286 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6287 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6288 && (TREE_CODE (type) != REFERENCE_TYPE
6289 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6290 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6291 rhs = decay_conversion (rhs);
6293 rhstype = TREE_TYPE (rhs);
6294 coder = TREE_CODE (rhstype);
6296 if (coder == ERROR_MARK)
6297 return error_mark_node;
6299 /* We accept references to incomplete types, so we can
6300 return here before checking if RHS is of complete type. */
6302 if (codel == REFERENCE_TYPE)
6304 /* This should eventually happen in convert_arguments. */
6305 int savew = 0, savee = 0;
6308 savew = warningcount, savee = errorcount;
6309 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6313 if (warningcount > savew)
6314 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6315 else if (errorcount > savee)
6316 error ("in passing argument %P of %q+D", parmnum, fndecl);
6322 exp = require_complete_type (exp);
6323 if (exp == error_mark_node)
6324 return error_mark_node;
6326 rhstype = non_reference (rhstype);
6328 type = complete_type (type);
6330 if (IS_AGGR_TYPE (type))
6331 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6333 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
6336 /* If RETVAL is the address of, or a reference to, a local variable or
6337 temporary give an appropriate warning. */
6340 maybe_warn_about_returning_address_of_local (tree retval)
6342 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6343 tree whats_returned = retval;
6347 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6348 whats_returned = TREE_OPERAND (whats_returned, 1);
6349 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
6350 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
6351 || TREE_CODE (whats_returned) == NOP_EXPR)
6352 whats_returned = TREE_OPERAND (whats_returned, 0);
6357 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6359 whats_returned = TREE_OPERAND (whats_returned, 0);
6361 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6363 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6364 || TREE_CODE (whats_returned) == TARGET_EXPR)
6366 warning (0, "returning reference to temporary");
6369 if (TREE_CODE (whats_returned) == VAR_DECL
6370 && DECL_NAME (whats_returned)
6371 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6373 warning (0, "reference to non-lvalue returned");
6378 while (TREE_CODE (whats_returned) == COMPONENT_REF
6379 || TREE_CODE (whats_returned) == ARRAY_REF)
6380 whats_returned = TREE_OPERAND (whats_returned, 0);
6382 if (DECL_P (whats_returned)
6383 && DECL_NAME (whats_returned)
6384 && DECL_FUNCTION_SCOPE_P (whats_returned)
6385 && !(TREE_STATIC (whats_returned)
6386 || TREE_PUBLIC (whats_returned)))
6388 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6389 warning (0, "reference to local variable %q+D returned",
6392 warning (0, "address of local variable %q+D returned",
6398 /* Check that returning RETVAL from the current function is valid.
6399 Return an expression explicitly showing all conversions required to
6400 change RETVAL into the function return type, and to assign it to
6401 the DECL_RESULT for the function. Set *NO_WARNING to true if
6402 code reaches end of non-void function warning shouldn't be issued
6403 on this RETURN_EXPR. */
6406 check_return_expr (tree retval, bool *no_warning)
6409 /* The type actually returned by the function, after any
6412 int fn_returns_value_p;
6414 *no_warning = false;
6416 /* A `volatile' function is one that isn't supposed to return, ever.
6417 (This is a G++ extension, used to get better code for functions
6418 that call the `volatile' function.) */
6419 if (TREE_THIS_VOLATILE (current_function_decl))
6420 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6422 /* Check for various simple errors. */
6423 if (DECL_DESTRUCTOR_P (current_function_decl))
6426 error ("returning a value from a destructor");
6429 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6431 if (in_function_try_handler)
6432 /* If a return statement appears in a handler of the
6433 function-try-block of a constructor, the program is ill-formed. */
6434 error ("cannot return from a handler of a function-try-block of a constructor");
6436 /* You can't return a value from a constructor. */
6437 error ("returning a value from a constructor");
6441 if (processing_template_decl)
6443 current_function_returns_value = 1;
6447 /* When no explicit return-value is given in a function with a named
6448 return value, the named return value is used. */
6449 result = DECL_RESULT (current_function_decl);
6450 valtype = TREE_TYPE (result);
6451 gcc_assert (valtype != NULL_TREE);
6452 fn_returns_value_p = !VOID_TYPE_P (valtype);
6453 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6456 /* Check for a return statement with no return value in a function
6457 that's supposed to return a value. */
6458 if (!retval && fn_returns_value_p)
6460 pedwarn ("return-statement with no value, in function returning %qT",
6462 /* Clear this, so finish_function won't say that we reach the
6463 end of a non-void function (which we don't, we gave a
6465 current_function_returns_null = 0;
6466 /* And signal caller that TREE_NO_WARNING should be set on the
6467 RETURN_EXPR to avoid control reaches end of non-void function
6468 warnings in tree-cfg.c. */
6471 /* Check for a return statement with a value in a function that
6472 isn't supposed to return a value. */
6473 else if (retval && !fn_returns_value_p)
6475 if (VOID_TYPE_P (TREE_TYPE (retval)))
6476 /* You can return a `void' value from a function of `void'
6477 type. In that case, we have to evaluate the expression for
6478 its side-effects. */
6479 finish_expr_stmt (retval);
6481 pedwarn ("return-statement with a value, in function "
6482 "returning 'void'");
6484 current_function_returns_null = 1;
6486 /* There's really no value to return, after all. */
6490 /* Remember that this function can sometimes return without a
6492 current_function_returns_null = 1;
6494 /* Remember that this function did return a value. */
6495 current_function_returns_value = 1;
6497 /* Check for erroneous operands -- but after giving ourselves a
6498 chance to provide an error about returning a value from a void
6500 if (error_operand_p (retval))
6502 current_function_return_value = error_mark_node;
6503 return error_mark_node;
6506 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
6507 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
6508 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
6509 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
6511 && null_ptr_cst_p (retval))
6512 warning (0, "%<operator new%> must not return NULL unless it is "
6513 "declared %<throw()%> (or -fcheck-new is in effect)");
6515 /* Effective C++ rule 15. See also start_function. */
6517 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
6521 /* The function return type must be a reference to the current
6523 if (TREE_CODE (valtype) == REFERENCE_TYPE
6524 && same_type_ignoring_top_level_qualifiers_p
6525 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
6527 /* Returning '*this' is obviously OK. */
6528 if (retval == current_class_ref)
6530 /* If we are calling a function whose return type is the same of
6531 the current class reference, it is ok. */
6532 else if (TREE_CODE (retval) == INDIRECT_REF
6533 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
6538 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
6541 /* The fabled Named Return Value optimization, as per [class.copy]/15:
6543 [...] For a function with a class return type, if the expression
6544 in the return statement is the name of a local object, and the cv-
6545 unqualified type of the local object is the same as the function
6546 return type, an implementation is permitted to omit creating the tem-
6547 porary object to hold the function return value [...]
6549 So, if this is a value-returning function that always returns the same
6550 local variable, remember it.
6552 It might be nice to be more flexible, and choose the first suitable
6553 variable even if the function sometimes returns something else, but
6554 then we run the risk of clobbering the variable we chose if the other
6555 returned expression uses the chosen variable somehow. And people expect
6556 this restriction, anyway. (jason 2000-11-19)
6558 See finish_function and finalize_nrv for the rest of this optimization. */
6560 if (fn_returns_value_p && flag_elide_constructors)
6562 if (retval != NULL_TREE
6563 && (current_function_return_value == NULL_TREE
6564 || current_function_return_value == retval)
6565 && TREE_CODE (retval) == VAR_DECL
6566 && DECL_CONTEXT (retval) == current_function_decl
6567 && ! TREE_STATIC (retval)
6568 && (DECL_ALIGN (retval)
6569 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6570 && same_type_p ((TYPE_MAIN_VARIANT
6571 (TREE_TYPE (retval))),
6573 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
6574 current_function_return_value = retval;
6576 current_function_return_value = error_mark_node;
6579 /* We don't need to do any conversions when there's nothing being
6584 /* Do any required conversions. */
6585 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6586 /* No conversions are required. */
6590 /* The type the function is declared to return. */
6591 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6593 /* The functype's return type will have been set to void, if it
6594 was an incomplete type. Just treat this as 'return;' */
6595 if (VOID_TYPE_P (functype))
6596 return error_mark_node;
6598 /* First convert the value to the function's return type, then
6599 to the type of return value's location to handle the
6600 case that functype is smaller than the valtype. */
6601 retval = convert_for_initialization
6602 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
6603 "return", NULL_TREE, 0);
6604 retval = convert (valtype, retval);
6606 /* If the conversion failed, treat this just like `return;'. */
6607 if (retval == error_mark_node)
6609 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6610 else if (! current_function_returns_struct
6611 && TREE_CODE (retval) == TARGET_EXPR
6612 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6613 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6614 TREE_OPERAND (retval, 0));
6616 maybe_warn_about_returning_address_of_local (retval);
6619 /* Actually copy the value returned into the appropriate location. */
6620 if (retval && retval != result)
6621 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
6627 /* Returns nonzero if the pointer-type FROM can be converted to the
6628 pointer-type TO via a qualification conversion. If CONSTP is -1,
6629 then we return nonzero if the pointers are similar, and the
6630 cv-qualification signature of FROM is a proper subset of that of TO.
6632 If CONSTP is positive, then all outer pointers have been
6636 comp_ptr_ttypes_real (tree to, tree from, int constp)
6638 bool to_more_cv_qualified = false;
6640 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6642 if (TREE_CODE (to) != TREE_CODE (from))
6645 if (TREE_CODE (from) == OFFSET_TYPE
6646 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
6647 TYPE_OFFSET_BASETYPE (to)))
6650 /* Const and volatile mean something different for function types,
6651 so the usual checks are not appropriate. */
6652 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6654 /* In Objective-C++, some types may have been 'volatilized' by
6655 the compiler for EH; when comparing them here, the volatile
6656 qualification must be ignored. */
6657 bool objc_quals_match = objc_type_quals_match (to, from);
6659 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
6662 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
6666 to_more_cv_qualified = true;
6670 constp &= TYPE_READONLY (to);
6673 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
6674 return ((constp >= 0 || to_more_cv_qualified)
6675 && same_type_ignoring_top_level_qualifiers_p (to, from));
6679 /* When comparing, say, char ** to char const **, this function takes
6680 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6681 types to this function. */
6684 comp_ptr_ttypes (tree to, tree from)
6686 return comp_ptr_ttypes_real (to, from, 1);
6689 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6690 type or inheritance-related types, regardless of cv-quals. */
6693 ptr_reasonably_similar (tree to, tree from)
6695 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6697 /* Any target type is similar enough to void. */
6698 if (TREE_CODE (to) == VOID_TYPE
6699 || TREE_CODE (from) == VOID_TYPE)
6702 if (TREE_CODE (to) != TREE_CODE (from))
6705 if (TREE_CODE (from) == OFFSET_TYPE
6706 && comptypes (TYPE_OFFSET_BASETYPE (to),
6707 TYPE_OFFSET_BASETYPE (from),
6708 COMPARE_BASE | COMPARE_DERIVED))
6711 if (TREE_CODE (to) == VECTOR_TYPE
6712 && vector_types_convertible_p (to, from))
6715 if (TREE_CODE (to) == INTEGER_TYPE
6716 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6719 if (TREE_CODE (to) == FUNCTION_TYPE)
6722 if (TREE_CODE (to) != POINTER_TYPE)
6724 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6725 COMPARE_BASE | COMPARE_DERIVED);
6729 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
6730 pointer-to-member types) are the same, ignoring cv-qualification at
6734 comp_ptr_ttypes_const (tree to, tree from)
6736 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6738 if (TREE_CODE (to) != TREE_CODE (from))
6741 if (TREE_CODE (from) == OFFSET_TYPE
6742 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6743 TYPE_OFFSET_BASETYPE (to)))
6746 if (TREE_CODE (to) != POINTER_TYPE)
6747 return same_type_ignoring_top_level_qualifiers_p (to, from);
6751 /* Returns the type qualifiers for this type, including the qualifiers on the
6752 elements for an array type. */
6755 cp_type_quals (tree type)
6757 type = strip_array_types (type);
6758 if (type == error_mark_node)
6759 return TYPE_UNQUALIFIED;
6760 return TYPE_QUALS (type);
6763 /* Returns nonzero if the TYPE contains a mutable member. */
6766 cp_has_mutable_p (tree type)
6768 type = strip_array_types (type);
6770 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6773 /* Apply the TYPE_QUALS to the new DECL. */
6775 cp_apply_type_quals_to_decl (int type_quals, tree decl)
6777 tree type = TREE_TYPE (decl);
6779 if (type == error_mark_node)
6782 if (TREE_CODE (type) == FUNCTION_TYPE
6783 && type_quals != TYPE_UNQUALIFIED)
6785 /* This was an error in C++98 (cv-qualifiers cannot be added to
6786 a function type), but DR 295 makes the code well-formed by
6787 dropping the extra qualifiers. */
6790 tree bad_type = build_qualified_type (type, type_quals);
6791 pedwarn ("ignoring %qV qualifiers added to function type %qT",
6795 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
6799 /* Avoid setting TREE_READONLY incorrectly. */
6800 if (/* If the object has a constructor, the constructor may modify
6802 TYPE_NEEDS_CONSTRUCTING (type)
6803 /* If the type isn't complete, we don't know yet if it will need
6805 || !COMPLETE_TYPE_P (type)
6806 /* If the type has a mutable component, that component might be
6808 || TYPE_HAS_MUTABLE_P (type))
6809 type_quals &= ~TYPE_QUAL_CONST;
6811 c_apply_type_quals_to_decl (type_quals, decl);
6814 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6815 exemplar types such that casting T1 to T2 is casting away constness
6816 if and only if there is no implicit conversion from T1 to T2. */
6819 casts_away_constness_r (tree *t1, tree *t2)
6824 /* [expr.const.cast]
6826 For multi-level pointer to members and multi-level mixed pointers
6827 and pointers to members (conv.qual), the "member" aspect of a
6828 pointer to member level is ignored when determining if a const
6829 cv-qualifier has been cast away. */
6830 /* [expr.const.cast]
6832 For two pointer types:
6834 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6835 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6838 casting from X1 to X2 casts away constness if, for a non-pointer
6839 type T there does not exist an implicit conversion (clause
6842 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6846 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6847 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
6848 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
6850 *t1 = cp_build_qualified_type (void_type_node,
6851 cp_type_quals (*t1));
6852 *t2 = cp_build_qualified_type (void_type_node,
6853 cp_type_quals (*t2));
6857 quals1 = cp_type_quals (*t1);
6858 quals2 = cp_type_quals (*t2);
6860 if (TYPE_PTRMEM_P (*t1))
6861 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
6863 *t1 = TREE_TYPE (*t1);
6864 if (TYPE_PTRMEM_P (*t2))
6865 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
6867 *t2 = TREE_TYPE (*t2);
6869 casts_away_constness_r (t1, t2);
6870 *t1 = build_pointer_type (*t1);
6871 *t2 = build_pointer_type (*t2);
6872 *t1 = cp_build_qualified_type (*t1, quals1);
6873 *t2 = cp_build_qualified_type (*t2, quals2);
6876 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6880 casts_away_constness (tree t1, tree t2)
6882 if (TREE_CODE (t2) == REFERENCE_TYPE)
6884 /* [expr.const.cast]
6886 Casting from an lvalue of type T1 to an lvalue of type T2
6887 using a reference cast casts away constness if a cast from an
6888 rvalue of type "pointer to T1" to the type "pointer to T2"
6889 casts away constness. */
6890 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6891 return casts_away_constness (build_pointer_type (t1),
6892 build_pointer_type (TREE_TYPE (t2)));
6895 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6896 /* [expr.const.cast]
6898 Casting from an rvalue of type "pointer to data member of X
6899 of type T1" to the type "pointer to data member of Y of type
6900 T2" casts away constness if a cast from an rvalue of type
6901 "pointer to T1" to the type "pointer to T2" casts away
6903 return casts_away_constness
6904 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6905 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6907 /* Casting away constness is only something that makes sense for
6908 pointer or reference types. */
6909 if (TREE_CODE (t1) != POINTER_TYPE
6910 || TREE_CODE (t2) != POINTER_TYPE)
6913 /* Top-level qualifiers don't matter. */
6914 t1 = TYPE_MAIN_VARIANT (t1);
6915 t2 = TYPE_MAIN_VARIANT (t2);
6916 casts_away_constness_r (&t1, &t2);
6917 if (!can_convert (t2, t1))
6923 /* If T is a REFERENCE_TYPE return the type to which T refers.
6924 Otherwise, return T itself. */
6927 non_reference (tree t)
6929 if (TREE_CODE (t) == REFERENCE_TYPE)
6935 /* Return nonzero if REF is an lvalue valid for this language;
6936 otherwise, print an error message and return zero. USE says
6937 how the lvalue is being used and so selects the error message. */
6940 lvalue_or_else (tree ref, enum lvalue_use use)
6942 int win = lvalue_p (ref);