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)
1244 enum tree_code type_code;
1246 const char *op_name;
1248 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1249 if (type == error_mark_node)
1250 return error_mark_node;
1252 if (dependent_type_p (type))
1254 value = build_min (op, size_type_node, type);
1255 TREE_READONLY (value) = 1;
1259 op_name = operator_name_info[(int) op].name;
1261 type = non_reference (type);
1262 type_code = TREE_CODE (type);
1264 if (type_code == METHOD_TYPE)
1266 if (complain && (pedantic || warn_pointer_arith))
1267 pedwarn ("invalid application of %qs to a member function", op_name);
1268 value = size_one_node;
1271 value = c_sizeof_or_alignof_type (complete_type (type),
1278 /* Process a sizeof expression where the operand is an expression. */
1281 cxx_sizeof_expr (tree e)
1283 if (e == error_mark_node)
1284 return error_mark_node;
1286 if (processing_template_decl)
1288 e = build_min (SIZEOF_EXPR, size_type_node, e);
1289 TREE_SIDE_EFFECTS (e) = 0;
1290 TREE_READONLY (e) = 1;
1295 if (TREE_CODE (e) == COMPONENT_REF
1296 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1297 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1299 error ("invalid application of %<sizeof%> to a bit-field");
1302 else if (is_overloaded_fn (e))
1304 pedwarn ("ISO C++ forbids applying %<sizeof%> to an expression of "
1308 else if (type_unknown_p (e))
1310 cxx_incomplete_type_error (e, TREE_TYPE (e));
1316 return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, true);
1319 /* Implement the __alignof keyword: Return the minimum required
1320 alignment of E, measured in bytes. For VAR_DECL's and
1321 FIELD_DECL's return DECL_ALIGN (which can be set from an
1322 "aligned" __attribute__ specification). */
1325 cxx_alignof_expr (tree e)
1329 if (e == error_mark_node)
1330 return error_mark_node;
1332 if (processing_template_decl)
1334 e = build_min (ALIGNOF_EXPR, size_type_node, e);
1335 TREE_SIDE_EFFECTS (e) = 0;
1336 TREE_READONLY (e) = 1;
1341 if (TREE_CODE (e) == VAR_DECL)
1342 t = size_int (DECL_ALIGN_UNIT (e));
1343 else if (TREE_CODE (e) == COMPONENT_REF
1344 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1345 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1347 error ("invalid application of %<__alignof%> to a bit-field");
1350 else if (TREE_CODE (e) == COMPONENT_REF
1351 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL)
1352 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1)));
1353 else if (is_overloaded_fn (e))
1355 pedwarn ("ISO C++ forbids applying %<__alignof%> to an expression of "
1359 else if (type_unknown_p (e))
1361 cxx_incomplete_type_error (e, TREE_TYPE (e));
1365 return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR, true);
1367 return fold_convert (size_type_node, t);
1370 /* Process a sizeof or alignof expression E with code OP where the operand
1371 is an expression. */
1374 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op)
1376 if (op == SIZEOF_EXPR)
1377 return cxx_sizeof_expr (e);
1379 return cxx_alignof_expr (e);
1382 /* EXPR is being used in a context that is not a function call.
1387 The expression can be used only as the left-hand operand of a
1388 member function call.
1390 [expr.mptr.operator]
1392 If the result of .* or ->* is a function, then that result can be
1393 used only as the operand for the function call operator ().
1395 by issuing an error message if appropriate. Returns true iff EXPR
1396 violates these rules. */
1399 invalid_nonstatic_memfn_p (tree expr)
1401 if (TREE_CODE (TREE_TYPE (expr)) == METHOD_TYPE)
1403 error ("invalid use of non-static member function");
1409 /* If EXP is a reference to a bitfield, and the type of EXP does not
1410 match the declared type of the bitfield, return the declared type
1411 of the bitfield. Otherwise, return NULL_TREE. */
1414 is_bitfield_expr_with_lowered_type (tree exp)
1418 if (TREE_CODE (exp) == COND_EXPR)
1420 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)))
1422 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2));
1424 if (TREE_CODE (exp) != COMPONENT_REF)
1426 field = TREE_OPERAND (exp, 1);
1427 if (TREE_CODE (field) != FIELD_DECL || !DECL_C_BIT_FIELD (field))
1429 if (same_type_ignoring_top_level_qualifiers_p
1430 (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field)))
1432 return DECL_BIT_FIELD_TYPE (field);
1435 /* Perform the conversions in [expr] that apply when an lvalue appears
1436 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1437 function-to-pointer conversions. In addition, manifest constants
1438 are replaced by their values, and bitfield references are converted
1439 to their declared types.
1441 Although the returned value is being used as an rvalue, this
1442 function does not wrap the returned expression in a
1443 NON_LVALUE_EXPR; the caller is expected to be mindful of the fact
1444 that the return value is no longer an lvalue. */
1447 decay_conversion (tree exp)
1450 enum tree_code code;
1452 type = TREE_TYPE (exp);
1453 if (type == error_mark_node)
1454 return error_mark_node;
1456 if (type_unknown_p (exp))
1458 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1459 return error_mark_node;
1462 exp = decl_constant_value (exp);
1463 if (error_operand_p (exp))
1464 return error_mark_node;
1466 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1467 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1468 code = TREE_CODE (type);
1469 if (code == VOID_TYPE)
1471 error ("void value not ignored as it ought to be");
1472 return error_mark_node;
1474 if (invalid_nonstatic_memfn_p (exp))
1475 return error_mark_node;
1476 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1477 return build_unary_op (ADDR_EXPR, exp, 0);
1478 if (code == ARRAY_TYPE)
1483 if (TREE_CODE (exp) == INDIRECT_REF)
1484 return build_nop (build_pointer_type (TREE_TYPE (type)),
1485 TREE_OPERAND (exp, 0));
1487 if (TREE_CODE (exp) == COMPOUND_EXPR)
1489 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1490 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1491 TREE_OPERAND (exp, 0), op1);
1495 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1497 error ("invalid use of non-lvalue array");
1498 return error_mark_node;
1501 ptrtype = build_pointer_type (TREE_TYPE (type));
1503 if (TREE_CODE (exp) == VAR_DECL)
1505 if (!cxx_mark_addressable (exp))
1506 return error_mark_node;
1507 adr = build_nop (ptrtype, build_address (exp));
1510 /* This way is better for a COMPONENT_REF since it can
1511 simplify the offset for a component. */
1512 adr = build_unary_op (ADDR_EXPR, exp, 1);
1513 return cp_convert (ptrtype, adr);
1516 /* If a bitfield is used in a context where integral promotion
1517 applies, then the caller is expected to have used
1518 default_conversion. That function promotes bitfields correctly
1519 before calling this function. At this point, if we have a
1520 bitfield referenced, we may assume that is not subject to
1521 promotion, and that, therefore, the type of the resulting rvalue
1522 is the declared type of the bitfield. */
1523 exp = convert_bitfield_to_declared_type (exp);
1525 /* We do not call rvalue() here because we do not want to wrap EXP
1526 in a NON_LVALUE_EXPR. */
1530 Non-class rvalues always have cv-unqualified types. */
1531 type = TREE_TYPE (exp);
1532 if (!CLASS_TYPE_P (type) && cp_type_quals (type))
1533 exp = build_nop (TYPE_MAIN_VARIANT (type), exp);
1538 /* Perform prepatory conversions, as part of the "usual arithmetic
1539 conversions". In particular, as per [expr]:
1541 Whenever an lvalue expression appears as an operand of an
1542 operator that expects the rvalue for that operand, the
1543 lvalue-to-rvalue, array-to-pointer, or function-to-pointer
1544 standard conversions are applied to convert the expression to an
1547 In addition, we perform integral promotions here, as those are
1548 applied to both operands to a binary operator before determining
1549 what additional conversions should apply. */
1552 default_conversion (tree exp)
1554 /* Perform the integral promotions first so that bitfield
1555 expressions (which may promote to "int", even if the bitfield is
1556 declared "unsigned") are promoted correctly. */
1557 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1558 exp = perform_integral_promotions (exp);
1559 /* Perform the other conversions. */
1560 exp = decay_conversion (exp);
1565 /* EXPR is an expression with an integral or enumeration type.
1566 Perform the integral promotions in [conv.prom], and return the
1570 perform_integral_promotions (tree expr)
1577 If the bitfield has an enumerated type, it is treated as any
1578 other value of that type for promotion purposes. */
1579 type = is_bitfield_expr_with_lowered_type (expr);
1580 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
1581 type = TREE_TYPE (expr);
1582 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1583 promoted_type = type_promotes_to (type);
1584 if (type != promoted_type)
1585 expr = cp_convert (promoted_type, expr);
1589 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1593 inline_conversion (tree exp)
1595 if (TREE_CODE (exp) == FUNCTION_DECL)
1596 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1601 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1602 decay_conversion to one. */
1605 string_conv_p (tree totype, tree exp, int warn)
1609 if (TREE_CODE (totype) != POINTER_TYPE)
1612 t = TREE_TYPE (totype);
1613 if (!same_type_p (t, char_type_node)
1614 && !same_type_p (t, wchar_type_node))
1617 if (TREE_CODE (exp) == STRING_CST)
1619 /* Make sure that we don't try to convert between char and wchar_t. */
1620 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1625 /* Is this a string constant which has decayed to 'const char *'? */
1626 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1627 if (!same_type_p (TREE_TYPE (exp), t))
1630 if (TREE_CODE (exp) != ADDR_EXPR
1631 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1635 /* This warning is not very useful, as it complains about printf. */
1637 warning (OPT_Wwrite_strings,
1638 "deprecated conversion from string constant to %qT",
1644 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1645 can, for example, use as an lvalue. This code used to be in
1646 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1647 expressions, where we're dealing with aggregates. But now it's again only
1648 called from unary_complex_lvalue. The case (in particular) that led to
1649 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1653 rationalize_conditional_expr (enum tree_code code, tree t)
1655 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1656 the first operand is always the one to be used if both operands
1657 are equal, so we know what conditional expression this used to be. */
1658 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1660 /* The following code is incorrect if either operand side-effects. */
1661 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0))
1662 && !TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)));
1664 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1665 ? LE_EXPR : GE_EXPR),
1666 TREE_OPERAND (t, 0),
1667 TREE_OPERAND (t, 1),
1668 /*overloaded_p=*/NULL),
1669 build_unary_op (code, TREE_OPERAND (t, 0), 0),
1670 build_unary_op (code, TREE_OPERAND (t, 1), 0));
1674 build_conditional_expr (TREE_OPERAND (t, 0),
1675 build_unary_op (code, TREE_OPERAND (t, 1), 0),
1676 build_unary_op (code, TREE_OPERAND (t, 2), 0));
1679 /* Given the TYPE of an anonymous union field inside T, return the
1680 FIELD_DECL for the field. If not found return NULL_TREE. Because
1681 anonymous unions can nest, we must also search all anonymous unions
1682 that are directly reachable. */
1685 lookup_anon_field (tree t, tree type)
1689 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1691 if (TREE_STATIC (field))
1693 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1696 /* If we find it directly, return the field. */
1697 if (DECL_NAME (field) == NULL_TREE
1698 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1703 /* Otherwise, it could be nested, search harder. */
1704 if (DECL_NAME (field) == NULL_TREE
1705 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1707 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1715 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1716 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1717 non-NULL, it indicates the path to the base used to name MEMBER.
1718 If PRESERVE_REFERENCE is true, the expression returned will have
1719 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1720 returned will have the type referred to by the reference.
1722 This function does not perform access control; that is either done
1723 earlier by the parser when the name of MEMBER is resolved to MEMBER
1724 itself, or later when overload resolution selects one of the
1725 functions indicated by MEMBER. */
1728 build_class_member_access_expr (tree object, tree member,
1729 tree access_path, bool preserve_reference)
1733 tree result = NULL_TREE;
1735 if (error_operand_p (object) || error_operand_p (member))
1736 return error_mark_node;
1738 gcc_assert (DECL_P (member) || BASELINK_P (member));
1742 The type of the first expression shall be "class object" (of a
1744 object_type = TREE_TYPE (object);
1745 if (!currently_open_class (object_type)
1746 && !complete_type_or_else (object_type, object))
1747 return error_mark_node;
1748 if (!CLASS_TYPE_P (object_type))
1750 error ("request for member %qD in %qE, which is of non-class type %qT",
1751 member, object, object_type);
1752 return error_mark_node;
1755 /* The standard does not seem to actually say that MEMBER must be a
1756 member of OBJECT_TYPE. However, that is clearly what is
1758 if (DECL_P (member))
1760 member_scope = DECL_CLASS_CONTEXT (member);
1762 if (TREE_DEPRECATED (member))
1763 warn_deprecated_use (member);
1766 member_scope = BINFO_TYPE (BASELINK_BINFO (member));
1767 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1768 presently be the anonymous union. Go outwards until we find a
1769 type related to OBJECT_TYPE. */
1770 while (ANON_AGGR_TYPE_P (member_scope)
1771 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1773 member_scope = TYPE_CONTEXT (member_scope);
1774 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1776 if (TREE_CODE (member) == FIELD_DECL)
1777 error ("invalid use of nonstatic data member %qE", member);
1779 error ("%qD is not a member of %qT", member, object_type);
1780 return error_mark_node;
1783 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1784 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1785 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1787 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1789 object = build_indirect_ref (temp, NULL);
1792 /* In [expr.ref], there is an explicit list of the valid choices for
1793 MEMBER. We check for each of those cases here. */
1794 if (TREE_CODE (member) == VAR_DECL)
1796 /* A static data member. */
1798 /* If OBJECT has side-effects, they are supposed to occur. */
1799 if (TREE_SIDE_EFFECTS (object))
1800 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1802 else if (TREE_CODE (member) == FIELD_DECL)
1804 /* A non-static data member. */
1809 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1810 && integer_zerop (TREE_OPERAND (object, 0)));
1812 /* Convert OBJECT to the type of MEMBER. */
1813 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1814 TYPE_MAIN_VARIANT (member_scope)))
1819 binfo = lookup_base (access_path ? access_path : object_type,
1820 member_scope, ba_unique, &kind);
1821 if (binfo == error_mark_node)
1822 return error_mark_node;
1824 /* It is invalid to try to get to a virtual base of a
1825 NULL object. The most common cause is invalid use of
1827 if (null_object_p && kind == bk_via_virtual)
1829 error ("invalid access to non-static data member %qD of "
1832 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
1833 return error_mark_node;
1836 /* Convert to the base. */
1837 object = build_base_path (PLUS_EXPR, object, binfo,
1839 /* If we found the base successfully then we should be able
1840 to convert to it successfully. */
1841 gcc_assert (object != error_mark_node);
1844 /* Complain about other invalid uses of offsetof, even though they will
1845 give the right answer. Note that we complain whether or not they
1846 actually used the offsetof macro, since there's no way to know at this
1847 point. So we just give a warning, instead of a pedwarn. */
1848 /* Do not produce this warning for base class field references, because
1849 we know for a fact that didn't come from offsetof. This does occur
1850 in various testsuite cases where a null object is passed where a
1851 vtable access is required. */
1852 if (null_object_p && warn_invalid_offsetof
1853 && CLASSTYPE_NON_POD_P (object_type)
1854 && !DECL_FIELD_IS_BASE (member)
1855 && !skip_evaluation)
1857 warning (0, "invalid access to non-static data member %qD of NULL object",
1859 warning (0, "(perhaps the %<offsetof%> macro was used incorrectly)");
1862 /* If MEMBER is from an anonymous aggregate, we have converted
1863 OBJECT so that it refers to the class containing the
1864 anonymous union. Generate a reference to the anonymous union
1865 itself, and recur to find MEMBER. */
1866 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
1867 /* When this code is called from build_field_call, the
1868 object already has the type of the anonymous union.
1869 That is because the COMPONENT_REF was already
1870 constructed, and was then disassembled before calling
1871 build_field_call. After the function-call code is
1872 cleaned up, this waste can be eliminated. */
1873 && (!same_type_ignoring_top_level_qualifiers_p
1874 (TREE_TYPE (object), DECL_CONTEXT (member))))
1876 tree anonymous_union;
1878 anonymous_union = lookup_anon_field (TREE_TYPE (object),
1879 DECL_CONTEXT (member));
1880 object = build_class_member_access_expr (object,
1882 /*access_path=*/NULL_TREE,
1883 preserve_reference);
1886 /* Compute the type of the field, as described in [expr.ref]. */
1887 type_quals = TYPE_UNQUALIFIED;
1888 member_type = TREE_TYPE (member);
1889 if (TREE_CODE (member_type) != REFERENCE_TYPE)
1891 type_quals = (cp_type_quals (member_type)
1892 | cp_type_quals (object_type));
1894 /* A field is const (volatile) if the enclosing object, or the
1895 field itself, is const (volatile). But, a mutable field is
1896 not const, even within a const object. */
1897 if (DECL_MUTABLE_P (member))
1898 type_quals &= ~TYPE_QUAL_CONST;
1899 member_type = cp_build_qualified_type (member_type, type_quals);
1902 result = build3 (COMPONENT_REF, member_type, object, member,
1904 result = fold_if_not_in_template (result);
1906 /* Mark the expression const or volatile, as appropriate. Even
1907 though we've dealt with the type above, we still have to mark the
1908 expression itself. */
1909 if (type_quals & TYPE_QUAL_CONST)
1910 TREE_READONLY (result) = 1;
1911 if (type_quals & TYPE_QUAL_VOLATILE)
1912 TREE_THIS_VOLATILE (result) = 1;
1914 else if (BASELINK_P (member))
1916 /* The member is a (possibly overloaded) member function. */
1920 /* If the MEMBER is exactly one static member function, then we
1921 know the type of the expression. Otherwise, we must wait
1922 until overload resolution has been performed. */
1923 functions = BASELINK_FUNCTIONS (member);
1924 if (TREE_CODE (functions) == FUNCTION_DECL
1925 && DECL_STATIC_FUNCTION_P (functions))
1926 type = TREE_TYPE (functions);
1928 type = unknown_type_node;
1929 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1930 base. That will happen when the function is called. */
1931 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
1933 else if (TREE_CODE (member) == CONST_DECL)
1935 /* The member is an enumerator. */
1937 /* If OBJECT has side-effects, they are supposed to occur. */
1938 if (TREE_SIDE_EFFECTS (object))
1939 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
1944 error ("invalid use of %qD", member);
1945 return error_mark_node;
1948 if (!preserve_reference)
1951 If E2 is declared to have type "reference to T", then ... the
1952 type of E1.E2 is T. */
1953 result = convert_from_reference (result);
1958 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1959 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1962 lookup_destructor (tree object, tree scope, tree dtor_name)
1964 tree object_type = TREE_TYPE (object);
1965 tree dtor_type = TREE_OPERAND (dtor_name, 0);
1968 if (scope && !check_dtor_name (scope, dtor_type))
1970 error ("qualified type %qT does not match destructor name ~%qT",
1972 return error_mark_node;
1974 if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
1976 error ("the type being destroyed is %qT, but the destructor refers to %qT",
1977 TYPE_MAIN_VARIANT (object_type), dtor_type);
1978 return error_mark_node;
1980 expr = lookup_member (dtor_type, complete_dtor_identifier,
1981 /*protect=*/1, /*want_type=*/false);
1982 expr = (adjust_result_of_qualified_name_lookup
1983 (expr, dtor_type, object_type));
1987 /* An expression of the form "A::template B" has been resolved to
1988 DECL. Issue a diagnostic if B is not a template or template
1992 check_template_keyword (tree decl)
1994 /* The standard says:
1998 If a name prefixed by the keyword template is not a member
1999 template, the program is ill-formed.
2001 DR 228 removed the restriction that the template be a member
2004 DR 96, if accepted would add the further restriction that explicit
2005 template arguments must be provided if the template keyword is
2006 used, but, as of 2005-10-16, that DR is still in "drafting". If
2007 this DR is accepted, then the semantic checks here can be
2008 simplified, as the entity named must in fact be a template
2009 specialization, rather than, as at present, a set of overloaded
2010 functions containing at least one template function. */
2011 if (TREE_CODE (decl) != TEMPLATE_DECL
2012 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
2014 if (!is_overloaded_fn (decl))
2015 pedwarn ("%qD is not a template", decl);
2020 if (BASELINK_P (fns))
2021 fns = BASELINK_FUNCTIONS (fns);
2024 tree fn = OVL_CURRENT (fns);
2025 if (TREE_CODE (fn) == TEMPLATE_DECL
2026 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2028 if (TREE_CODE (fn) == FUNCTION_DECL
2029 && DECL_USE_TEMPLATE (fn)
2030 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
2032 fns = OVL_NEXT (fns);
2035 pedwarn ("%qD is not a template", decl);
2040 /* This function is called by the parser to process a class member
2041 access expression of the form OBJECT.NAME. NAME is a node used by
2042 the parser to represent a name; it is not yet a DECL. It may,
2043 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2044 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2045 there is no reason to do the lookup twice, so the parser keeps the
2046 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2047 be a template via the use of the "A::template B" syntax. */
2050 finish_class_member_access_expr (tree object, tree name, bool template_p)
2055 tree access_path = NULL_TREE;
2056 tree orig_object = object;
2057 tree orig_name = name;
2059 if (object == error_mark_node || name == error_mark_node)
2060 return error_mark_node;
2062 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2063 if (!objc_is_public (object, name))
2064 return error_mark_node;
2066 object_type = TREE_TYPE (object);
2068 if (processing_template_decl)
2070 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2071 dependent_type_p (object_type)
2072 /* If NAME is just an IDENTIFIER_NODE, then the expression
2074 || TREE_CODE (object) == IDENTIFIER_NODE
2075 /* If NAME is "f<args>", where either 'f' or 'args' is
2076 dependent, then the expression is dependent. */
2077 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2078 && dependent_template_id_p (TREE_OPERAND (name, 0),
2079 TREE_OPERAND (name, 1)))
2080 /* If NAME is "T::X" where "T" is dependent, then the
2081 expression is dependent. */
2082 || (TREE_CODE (name) == SCOPE_REF
2083 && TYPE_P (TREE_OPERAND (name, 0))
2084 && dependent_type_p (TREE_OPERAND (name, 0))))
2085 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2086 object = build_non_dependent_expr (object);
2091 The type of the first expression shall be "class object" (of a
2093 if (!currently_open_class (object_type)
2094 && !complete_type_or_else (object_type, object))
2095 return error_mark_node;
2096 if (!CLASS_TYPE_P (object_type))
2098 error ("request for member %qD in %qE, which is of non-class type %qT",
2099 name, object, object_type);
2100 return error_mark_node;
2103 if (BASELINK_P (name))
2104 /* A member function that has already been looked up. */
2108 bool is_template_id = false;
2109 tree template_args = NULL_TREE;
2112 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2114 is_template_id = true;
2115 template_args = TREE_OPERAND (name, 1);
2116 name = TREE_OPERAND (name, 0);
2118 if (TREE_CODE (name) == OVERLOAD)
2119 name = DECL_NAME (get_first_fn (name));
2120 else if (DECL_P (name))
2121 name = DECL_NAME (name);
2124 if (TREE_CODE (name) == SCOPE_REF)
2126 /* A qualified name. The qualifying class or namespace `S'
2127 has already been looked up; it is either a TYPE or a
2129 scope = TREE_OPERAND (name, 0);
2130 name = TREE_OPERAND (name, 1);
2132 /* If SCOPE is a namespace, then the qualified name does not
2133 name a member of OBJECT_TYPE. */
2134 if (TREE_CODE (scope) == NAMESPACE_DECL)
2136 error ("%<%D::%D%> is not a member of %qT",
2137 scope, name, object_type);
2138 return error_mark_node;
2141 gcc_assert (CLASS_TYPE_P (scope));
2142 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2143 || TREE_CODE (name) == BIT_NOT_EXPR);
2145 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2146 access_path = lookup_base (object_type, scope, ba_check, NULL);
2147 if (access_path == error_mark_node)
2148 return error_mark_node;
2151 error ("%qT is not a base of %qT", scope, object_type);
2152 return error_mark_node;
2158 access_path = object_type;
2161 if (TREE_CODE (name) == BIT_NOT_EXPR)
2162 member = lookup_destructor (object, scope, name);
2165 /* Look up the member. */
2166 member = lookup_member (access_path, name, /*protect=*/1,
2167 /*want_type=*/false);
2168 if (member == NULL_TREE)
2170 error ("%qD has no member named %qE", object_type, name);
2171 return error_mark_node;
2173 if (member == error_mark_node)
2174 return error_mark_node;
2179 tree template = member;
2181 if (BASELINK_P (template))
2182 template = lookup_template_function (template, template_args);
2185 error ("%qD is not a member template function", name);
2186 return error_mark_node;
2191 if (TREE_DEPRECATED (member))
2192 warn_deprecated_use (member);
2195 check_template_keyword (member);
2197 expr = build_class_member_access_expr (object, member, access_path,
2198 /*preserve_reference=*/false);
2199 if (processing_template_decl && expr != error_mark_node)
2201 if (BASELINK_P (member))
2203 if (TREE_CODE (orig_name) == SCOPE_REF)
2204 BASELINK_QUALIFIED_P (member) = 1;
2207 return build_min_non_dep (COMPONENT_REF, expr,
2208 orig_object, orig_name,
2215 /* Return an expression for the MEMBER_NAME field in the internal
2216 representation of PTRMEM, a pointer-to-member function. (Each
2217 pointer-to-member function type gets its own RECORD_TYPE so it is
2218 more convenient to access the fields by name than by FIELD_DECL.)
2219 This routine converts the NAME to a FIELD_DECL and then creates the
2220 node for the complete expression. */
2223 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2229 /* This code is a stripped down version of
2230 build_class_member_access_expr. It does not work to use that
2231 routine directly because it expects the object to be of class
2233 ptrmem_type = TREE_TYPE (ptrmem);
2234 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2235 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2236 /*want_type=*/false);
2237 member_type = cp_build_qualified_type (TREE_TYPE (member),
2238 cp_type_quals (ptrmem_type));
2239 return fold_build3 (COMPONENT_REF, member_type,
2240 ptrmem, member, NULL_TREE);
2243 /* Given an expression PTR for a pointer, return an expression
2244 for the value pointed to.
2245 ERRORSTRING is the name of the operator to appear in error messages.
2247 This function may need to overload OPERATOR_FNNAME.
2248 Must also handle REFERENCE_TYPEs for C++. */
2251 build_x_indirect_ref (tree expr, const char *errorstring)
2253 tree orig_expr = expr;
2256 if (processing_template_decl)
2258 if (type_dependent_expression_p (expr))
2259 return build_min_nt (INDIRECT_REF, expr);
2260 expr = build_non_dependent_expr (expr);
2263 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2264 NULL_TREE, /*overloaded_p=*/NULL);
2266 rval = build_indirect_ref (expr, errorstring);
2268 if (processing_template_decl && rval != error_mark_node)
2269 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2275 build_indirect_ref (tree ptr, const char *errorstring)
2279 if (ptr == error_mark_node)
2280 return error_mark_node;
2282 if (ptr == current_class_ptr)
2283 return current_class_ref;
2285 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2286 ? ptr : decay_conversion (ptr));
2287 type = TREE_TYPE (pointer);
2289 if (POINTER_TYPE_P (type))
2293 If the type of the expression is "pointer to T," the type
2294 of the result is "T."
2296 We must use the canonical variant because certain parts of
2297 the back end, like fold, do pointer comparisons between
2299 tree t = canonical_type_variant (TREE_TYPE (type));
2301 if (VOID_TYPE_P (t))
2303 /* A pointer to incomplete type (other than cv void) can be
2304 dereferenced [expr.unary.op]/1 */
2305 error ("%qT is not a pointer-to-object type", type);
2306 return error_mark_node;
2308 else if (TREE_CODE (pointer) == ADDR_EXPR
2309 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2310 /* The POINTER was something like `&x'. We simplify `*&x' to
2312 return TREE_OPERAND (pointer, 0);
2315 tree ref = build1 (INDIRECT_REF, t, pointer);
2317 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2318 so that we get the proper error message if the result is used
2319 to assign to. Also, &* is supposed to be a no-op. */
2320 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2321 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2322 TREE_SIDE_EFFECTS (ref)
2323 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2327 /* `pointer' won't be an error_mark_node if we were given a
2328 pointer to member, so it's cool to check for this here. */
2329 else if (TYPE_PTR_TO_MEMBER_P (type))
2330 error ("invalid use of %qs on pointer to member", errorstring);
2331 else if (pointer != error_mark_node)
2334 error ("invalid type argument of %qs", errorstring);
2336 error ("invalid type argument");
2338 return error_mark_node;
2341 /* This handles expressions of the form "a[i]", which denotes
2344 This is logically equivalent in C to *(a+i), but we may do it differently.
2345 If A is a variable or a member, we generate a primitive ARRAY_REF.
2346 This avoids forcing the array out of registers, and can work on
2347 arrays that are not lvalues (for example, members of structures returned
2350 If INDEX is of some user-defined type, it must be converted to
2351 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2352 will inherit the type of the array, which will be some pointer type. */
2355 build_array_ref (tree array, tree idx)
2359 error ("subscript missing in array reference");
2360 return error_mark_node;
2363 if (TREE_TYPE (array) == error_mark_node
2364 || TREE_TYPE (idx) == error_mark_node)
2365 return error_mark_node;
2367 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2369 switch (TREE_CODE (array))
2373 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2374 return build2 (COMPOUND_EXPR, TREE_TYPE (value),
2375 TREE_OPERAND (array, 0), value);
2379 return build_conditional_expr
2380 (TREE_OPERAND (array, 0),
2381 build_array_ref (TREE_OPERAND (array, 1), idx),
2382 build_array_ref (TREE_OPERAND (array, 2), idx));
2388 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2392 warn_array_subscript_with_type_char (idx);
2394 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2396 error ("array subscript is not an integer");
2397 return error_mark_node;
2400 /* Apply integral promotions *after* noticing character types.
2401 (It is unclear why we do these promotions -- the standard
2402 does not say that we should. In fact, the natural thing would
2403 seem to be to convert IDX to ptrdiff_t; we're performing
2404 pointer arithmetic.) */
2405 idx = perform_integral_promotions (idx);
2407 /* An array that is indexed by a non-constant
2408 cannot be stored in a register; we must be able to do
2409 address arithmetic on its address.
2410 Likewise an array of elements of variable size. */
2411 if (TREE_CODE (idx) != INTEGER_CST
2412 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2413 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2416 if (!cxx_mark_addressable (array))
2417 return error_mark_node;
2420 /* An array that is indexed by a constant value which is not within
2421 the array bounds cannot be stored in a register either; because we
2422 would get a crash in store_bit_field/extract_bit_field when trying
2423 to access a non-existent part of the register. */
2424 if (TREE_CODE (idx) == INTEGER_CST
2425 && TYPE_DOMAIN (TREE_TYPE (array))
2426 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2428 if (!cxx_mark_addressable (array))
2429 return error_mark_node;
2432 if (pedantic && !lvalue_p (array))
2433 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2435 /* Note in C++ it is valid to subscript a `register' array, since
2436 it is valid to take the address of something with that
2437 storage specification. */
2441 while (TREE_CODE (foo) == COMPONENT_REF)
2442 foo = TREE_OPERAND (foo, 0);
2443 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2444 warning (OPT_Wextra, "subscripting array declared %<register%>");
2447 type = TREE_TYPE (TREE_TYPE (array));
2448 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2449 /* Array ref is const/volatile if the array elements are
2450 or if the array is.. */
2451 TREE_READONLY (rval)
2452 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2453 TREE_SIDE_EFFECTS (rval)
2454 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2455 TREE_THIS_VOLATILE (rval)
2456 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2457 return require_complete_type (fold_if_not_in_template (rval));
2461 tree ar = default_conversion (array);
2462 tree ind = default_conversion (idx);
2464 /* Put the integer in IND to simplify error checking. */
2465 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2472 if (ar == error_mark_node)
2475 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2477 error ("subscripted value is neither array nor pointer");
2478 return error_mark_node;
2480 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2482 error ("array subscript is not an integer");
2483 return error_mark_node;
2486 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2491 /* Resolve a pointer to member function. INSTANCE is the object
2492 instance to use, if the member points to a virtual member.
2494 This used to avoid checking for virtual functions if basetype
2495 has no virtual functions, according to an earlier ANSI draft.
2496 With the final ISO C++ rules, such an optimization is
2497 incorrect: A pointer to a derived member can be static_cast
2498 to pointer-to-base-member, as long as the dynamic object
2499 later has the right member. */
2502 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2504 if (TREE_CODE (function) == OFFSET_REF)
2505 function = TREE_OPERAND (function, 1);
2507 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2509 tree idx, delta, e1, e2, e3, vtbl, basetype;
2510 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2512 tree instance_ptr = *instance_ptrptr;
2513 tree instance_save_expr = 0;
2514 if (instance_ptr == error_mark_node)
2516 if (TREE_CODE (function) == PTRMEM_CST)
2518 /* Extracting the function address from a pmf is only
2519 allowed with -Wno-pmf-conversions. It only works for
2521 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2522 e1 = convert (fntype, e1);
2527 error ("object missing in use of %qE", function);
2528 return error_mark_node;
2532 if (TREE_SIDE_EFFECTS (instance_ptr))
2533 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2535 if (TREE_SIDE_EFFECTS (function))
2536 function = save_expr (function);
2538 /* Start by extracting all the information from the PMF itself. */
2539 e3 = pfn_from_ptrmemfunc (function);
2540 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2541 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2542 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2544 case ptrmemfunc_vbit_in_pfn:
2545 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2546 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2549 case ptrmemfunc_vbit_in_delta:
2550 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2551 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2558 /* Convert down to the right base before using the instance. A
2559 special case is that in a pointer to member of class C, C may
2560 be incomplete. In that case, the function will of course be
2561 a member of C, and no conversion is required. In fact,
2562 lookup_base will fail in that case, because incomplete
2563 classes do not have BINFOs. */
2564 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2565 if (!same_type_ignoring_top_level_qualifiers_p
2566 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2568 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2569 basetype, ba_check, NULL);
2570 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2572 if (instance_ptr == error_mark_node)
2573 return error_mark_node;
2575 /* ...and then the delta in the PMF. */
2576 instance_ptr = build2 (PLUS_EXPR, TREE_TYPE (instance_ptr),
2577 instance_ptr, delta);
2579 /* Hand back the adjusted 'this' argument to our caller. */
2580 *instance_ptrptr = instance_ptr;
2582 /* Next extract the vtable pointer from the object. */
2583 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2585 vtbl = build_indirect_ref (vtbl, NULL);
2587 /* Finally, extract the function pointer from the vtable. */
2588 e2 = fold_build2 (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx);
2589 e2 = build_indirect_ref (e2, NULL);
2590 TREE_CONSTANT (e2) = 1;
2591 TREE_INVARIANT (e2) = 1;
2593 /* When using function descriptors, the address of the
2594 vtable entry is treated as a function pointer. */
2595 if (TARGET_VTABLE_USES_DESCRIPTORS)
2596 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2597 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2599 TREE_TYPE (e2) = TREE_TYPE (e3);
2600 e1 = build_conditional_expr (e1, e2, e3);
2602 /* Make sure this doesn't get evaluated first inside one of the
2603 branches of the COND_EXPR. */
2604 if (instance_save_expr)
2605 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2606 instance_save_expr, e1);
2614 build_function_call (tree function, tree params)
2616 tree fntype, fndecl;
2617 tree coerced_params;
2618 tree name = NULL_TREE;
2620 tree original = function;
2622 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2623 expressions, like those used for ObjC messenger dispatches. */
2624 function = objc_rewrite_function_call (function, params);
2626 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2627 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2628 if (TREE_CODE (function) == NOP_EXPR
2629 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2630 function = TREE_OPERAND (function, 0);
2632 if (TREE_CODE (function) == FUNCTION_DECL)
2634 name = DECL_NAME (function);
2636 mark_used (function);
2639 /* Convert anything with function type to a pointer-to-function. */
2640 if (pedantic && DECL_MAIN_P (function))
2641 pedwarn ("ISO C++ forbids calling %<::main%> from within program");
2643 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2644 (because calling an inline function does not mean the function
2645 needs to be separately compiled). */
2647 if (DECL_INLINE (function))
2648 function = inline_conversion (function);
2650 function = build_addr_func (function);
2656 function = build_addr_func (function);
2659 if (function == error_mark_node)
2660 return error_mark_node;
2662 fntype = TREE_TYPE (function);
2664 if (TYPE_PTRMEMFUNC_P (fntype))
2666 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2667 "function in %<%E (...)%>",
2669 return error_mark_node;
2672 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2673 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2675 if (!((TREE_CODE (fntype) == POINTER_TYPE
2676 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2678 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2680 error ("%qE cannot be used as a function", original);
2681 return error_mark_node;
2684 /* fntype now gets the type of function pointed to. */
2685 fntype = TREE_TYPE (fntype);
2687 /* Convert the parameters to the types declared in the
2688 function prototype, or apply default promotions. */
2690 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2691 params, fndecl, LOOKUP_NORMAL);
2692 if (coerced_params == error_mark_node)
2693 return error_mark_node;
2695 /* Check for errors in format strings and inappropriately
2698 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params,
2699 TYPE_ARG_TYPES (fntype));
2701 return build_cxx_call (function, coerced_params);
2704 /* Convert the actual parameter expressions in the list VALUES
2705 to the types in the list TYPELIST.
2706 If parmdecls is exhausted, or when an element has NULL as its type,
2707 perform the default conversions.
2709 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2711 This is also where warnings about wrong number of args are generated.
2713 Return a list of expressions for the parameters as converted.
2715 Both VALUES and the returned value are chains of TREE_LIST nodes
2716 with the elements of the list in the TREE_VALUE slots of those nodes.
2718 In C++, unspecified trailing parameters can be filled in with their
2719 default arguments, if such were specified. Do so here. */
2722 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2724 tree typetail, valtail;
2725 tree result = NULL_TREE;
2726 const char *called_thing = 0;
2729 /* Argument passing is always copy-initialization. */
2730 flags |= LOOKUP_ONLYCONVERTING;
2734 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2736 if (DECL_NAME (fndecl) == NULL_TREE
2737 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2738 called_thing = "constructor";
2740 called_thing = "member function";
2743 called_thing = "function";
2746 for (valtail = values, typetail = typelist;
2748 valtail = TREE_CHAIN (valtail), i++)
2750 tree type = typetail ? TREE_VALUE (typetail) : 0;
2751 tree val = TREE_VALUE (valtail);
2753 if (val == error_mark_node || type == error_mark_node)
2754 return error_mark_node;
2756 if (type == void_type_node)
2760 error ("too many arguments to %s %q+#D", called_thing, fndecl);
2761 error ("at this point in file");
2764 error ("too many arguments to function");
2765 /* In case anybody wants to know if this argument
2768 TREE_TYPE (tree_last (result)) = error_mark_node;
2772 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2773 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2774 if (TREE_CODE (val) == NOP_EXPR
2775 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2776 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2777 val = TREE_OPERAND (val, 0);
2779 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2781 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2782 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2783 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2784 val = decay_conversion (val);
2787 if (val == error_mark_node)
2788 return error_mark_node;
2792 /* Formal parm type is specified by a function prototype. */
2795 if (!COMPLETE_TYPE_P (complete_type (type)))
2798 error ("parameter %P of %qD has incomplete type %qT",
2801 error ("parameter %P has incomplete type %qT", i, type);
2802 parmval = error_mark_node;
2806 parmval = convert_for_initialization
2807 (NULL_TREE, type, val, flags,
2808 "argument passing", fndecl, i);
2809 parmval = convert_for_arg_passing (type, parmval);
2812 if (parmval == error_mark_node)
2813 return error_mark_node;
2815 result = tree_cons (NULL_TREE, parmval, result);
2819 if (fndecl && DECL_BUILT_IN (fndecl)
2820 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2821 /* Don't do ellipsis conversion for __built_in_constant_p
2822 as this will result in spurious warnings for non-POD
2824 val = require_complete_type (val);
2826 val = convert_arg_to_ellipsis (val);
2828 result = tree_cons (NULL_TREE, val, result);
2832 typetail = TREE_CHAIN (typetail);
2835 if (typetail != 0 && typetail != void_list_node)
2837 /* See if there are default arguments that can be used. */
2838 if (TREE_PURPOSE (typetail)
2839 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2841 for (; typetail != void_list_node; ++i)
2844 = convert_default_arg (TREE_VALUE (typetail),
2845 TREE_PURPOSE (typetail),
2848 if (parmval == error_mark_node)
2849 return error_mark_node;
2851 result = tree_cons (0, parmval, result);
2852 typetail = TREE_CHAIN (typetail);
2853 /* ends with `...'. */
2854 if (typetail == NULL_TREE)
2862 error ("too few arguments to %s %q+#D", called_thing, fndecl);
2863 error ("at this point in file");
2866 error ("too few arguments to function");
2867 return error_mark_node;
2871 return nreverse (result);
2874 /* Build a binary-operation expression, after performing default
2875 conversions on the operands. CODE is the kind of expression to build. */
2878 build_x_binary_op (enum tree_code code, tree arg1, tree arg2,
2888 if (processing_template_decl)
2890 if (type_dependent_expression_p (arg1)
2891 || type_dependent_expression_p (arg2))
2892 return build_min_nt (code, arg1, arg2);
2893 arg1 = build_non_dependent_expr (arg1);
2894 arg2 = build_non_dependent_expr (arg2);
2897 if (code == DOTSTAR_EXPR)
2898 expr = build_m_component_ref (arg1, arg2);
2900 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
2903 if (processing_template_decl && expr != error_mark_node)
2904 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
2909 /* Build a binary-operation expression without default conversions.
2910 CODE is the kind of expression to build.
2911 This function differs from `build' in several ways:
2912 the data type of the result is computed and recorded in it,
2913 warnings are generated if arg data types are invalid,
2914 special handling for addition and subtraction of pointers is known,
2915 and some optimization is done (operations on narrow ints
2916 are done in the narrower type when that gives the same result).
2917 Constant folding is also done before the result is returned.
2919 Note that the operands will never have enumeral types
2920 because either they have just had the default conversions performed
2921 or they have both just been converted to some other type in which
2922 the arithmetic is to be done.
2924 C++: must do special pointer arithmetic when implementing
2925 multiple inheritance, and deal with pointer to member functions. */
2928 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2929 int convert_p ATTRIBUTE_UNUSED)
2932 enum tree_code code0, code1;
2934 const char *invalid_op_diag;
2936 /* Expression code to give to the expression when it is built.
2937 Normally this is CODE, which is what the caller asked for,
2938 but in some special cases we change it. */
2939 enum tree_code resultcode = code;
2941 /* Data type in which the computation is to be performed.
2942 In the simplest cases this is the common type of the arguments. */
2943 tree result_type = NULL;
2945 /* Nonzero means operands have already been type-converted
2946 in whatever way is necessary.
2947 Zero means they need to be converted to RESULT_TYPE. */
2950 /* Nonzero means create the expression with this type, rather than
2952 tree build_type = 0;
2954 /* Nonzero means after finally constructing the expression
2955 convert it to this type. */
2956 tree final_type = 0;
2960 /* Nonzero if this is an operation like MIN or MAX which can
2961 safely be computed in short if both args are promoted shorts.
2962 Also implies COMMON.
2963 -1 indicates a bitwise operation; this makes a difference
2964 in the exact conditions for when it is safe to do the operation
2965 in a narrower mode. */
2968 /* Nonzero if this is a comparison operation;
2969 if both args are promoted shorts, compare the original shorts.
2970 Also implies COMMON. */
2971 int short_compare = 0;
2973 /* Nonzero if this is a right-shift operation, which can be computed on the
2974 original short and then promoted if the operand is a promoted short. */
2975 int short_shift = 0;
2977 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2980 /* True if both operands have arithmetic type. */
2981 bool arithmetic_types_p;
2983 /* Apply default conversions. */
2987 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2988 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2989 || code == TRUTH_XOR_EXPR)
2991 if (!really_overloaded_fn (op0))
2992 op0 = decay_conversion (op0);
2993 if (!really_overloaded_fn (op1))
2994 op1 = decay_conversion (op1);
2998 if (!really_overloaded_fn (op0))
2999 op0 = default_conversion (op0);
3000 if (!really_overloaded_fn (op1))
3001 op1 = default_conversion (op1);
3004 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
3005 STRIP_TYPE_NOPS (op0);
3006 STRIP_TYPE_NOPS (op1);
3008 /* DTRT if one side is an overloaded function, but complain about it. */
3009 if (type_unknown_p (op0))
3011 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3012 if (t != error_mark_node)
3014 pedwarn ("assuming cast to type %qT from overloaded function",
3019 if (type_unknown_p (op1))
3021 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3022 if (t != error_mark_node)
3024 pedwarn ("assuming cast to type %qT from overloaded function",
3030 type0 = TREE_TYPE (op0);
3031 type1 = TREE_TYPE (op1);
3033 /* The expression codes of the data types of the arguments tell us
3034 whether the arguments are integers, floating, pointers, etc. */
3035 code0 = TREE_CODE (type0);
3036 code1 = TREE_CODE (type1);
3038 /* If an error was already reported for one of the arguments,
3039 avoid reporting another error. */
3041 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3042 return error_mark_node;
3044 if ((invalid_op_diag
3045 = targetm.invalid_binary_op (code, type0, type1)))
3047 error (invalid_op_diag);
3048 return error_mark_node;
3054 /* Subtraction of two similar pointers.
3055 We must subtract them as integers, then divide by object size. */
3056 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3057 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3059 return pointer_diff (op0, op1, common_type (type0, type1));
3060 /* In all other cases except pointer - int, the usual arithmetic
3062 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
3067 /* The pointer - int case is just like pointer + int; fall
3070 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
3071 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
3075 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
3076 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
3077 if (processing_template_decl)
3079 result_type = TREE_TYPE (ptr_operand);
3082 return cp_pointer_int_sum (code,
3093 case TRUNC_DIV_EXPR:
3095 case FLOOR_DIV_EXPR:
3096 case ROUND_DIV_EXPR:
3097 case EXACT_DIV_EXPR:
3098 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3099 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3100 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3101 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3103 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
3104 warning (OPT_Wdiv_by_zero, "division by zero in %<%E / 0%>", op0);
3105 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
3106 warning (OPT_Wdiv_by_zero, "division by zero in %<%E / 0.%>", op0);
3108 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3109 code0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3110 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
3111 code1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3113 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
3114 resultcode = RDIV_EXPR;
3116 /* When dividing two signed integers, we have to promote to int.
3117 unless we divide by a constant != -1. Note that default
3118 conversion will have been performed on the operands at this
3119 point, so we have to dig out the original type to find out if
3121 shorten = ((TREE_CODE (op0) == NOP_EXPR
3122 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3123 || (TREE_CODE (op1) == INTEGER_CST
3124 && ! integer_all_onesp (op1)));
3133 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3134 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE))
3138 case TRUNC_MOD_EXPR:
3139 case FLOOR_MOD_EXPR:
3140 if (code1 == INTEGER_TYPE && integer_zerop (op1))
3141 warning (OPT_Wdiv_by_zero, "division by zero in %<%E %% 0%>", op0);
3142 else if (code1 == REAL_TYPE && real_zerop (op1))
3143 warning (OPT_Wdiv_by_zero, "division by zero in %<%E %% 0.%>", op0);
3145 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3147 /* Although it would be tempting to shorten always here, that loses
3148 on some targets, since the modulo instruction is undefined if the
3149 quotient can't be represented in the computation mode. We shorten
3150 only if unsigned or if dividing by something we know != -1. */
3151 shorten = ((TREE_CODE (op0) == NOP_EXPR
3152 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3153 || (TREE_CODE (op1) == INTEGER_CST
3154 && ! integer_all_onesp (op1)));
3159 case TRUTH_ANDIF_EXPR:
3160 case TRUTH_ORIF_EXPR:
3161 case TRUTH_AND_EXPR:
3163 result_type = boolean_type_node;
3166 /* Shift operations: result has same type as first operand;
3167 always convert second operand to int.
3168 Also set SHORT_SHIFT if shifting rightward. */
3171 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3173 result_type = type0;
3174 if (TREE_CODE (op1) == INTEGER_CST)
3176 if (tree_int_cst_lt (op1, integer_zero_node))
3177 warning (0, "right shift count is negative");
3180 if (! integer_zerop (op1))
3182 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3183 warning (0, "right shift count >= width of type");
3186 /* Convert the shift-count to an integer, regardless of
3187 size of value being shifted. */
3188 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3189 op1 = cp_convert (integer_type_node, op1);
3190 /* Avoid converting op1 to result_type later. */
3196 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3198 result_type = type0;
3199 if (TREE_CODE (op1) == INTEGER_CST)
3201 if (tree_int_cst_lt (op1, integer_zero_node))
3202 warning (0, "left shift count is negative");
3203 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3204 warning (0, "left shift count >= width of type");
3206 /* Convert the shift-count to an integer, regardless of
3207 size of value being shifted. */
3208 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3209 op1 = cp_convert (integer_type_node, op1);
3210 /* Avoid converting op1 to result_type later. */
3217 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3219 result_type = type0;
3220 if (TREE_CODE (op1) == INTEGER_CST)
3222 if (tree_int_cst_lt (op1, integer_zero_node))
3223 warning (0, "%s rotate count is negative",
3224 (code == LROTATE_EXPR) ? "left" : "right");
3225 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3226 warning (0, "%s rotate count >= width of type",
3227 (code == LROTATE_EXPR) ? "left" : "right");
3229 /* Convert the shift-count to an integer, regardless of
3230 size of value being shifted. */
3231 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3232 op1 = cp_convert (integer_type_node, op1);
3238 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
3239 warning (OPT_Wfloat_equal,
3240 "comparing floating point with == or != is unsafe");
3241 if ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3242 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0)))
3243 warning (OPT_Wstring_literal_comparison,
3244 "comparison with string literal");
3246 build_type = boolean_type_node;
3247 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3248 || code0 == COMPLEX_TYPE)
3249 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3250 || code1 == COMPLEX_TYPE))
3252 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3253 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3254 result_type = composite_pointer_type (type0, type1, op0, op1,
3256 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3257 && null_ptr_cst_p (op1))
3258 result_type = type0;
3259 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3260 && null_ptr_cst_p (op0))
3261 result_type = type1;
3262 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3264 result_type = type0;
3265 error ("ISO C++ forbids comparison between pointer and integer");
3267 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3269 result_type = type1;
3270 error ("ISO C++ forbids comparison between pointer and integer");
3272 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3274 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3275 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3276 result_type = TREE_TYPE (op0);
3278 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3279 return cp_build_binary_op (code, op1, op0);
3280 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
3281 && same_type_p (type0, type1))
3283 /* E will be the final comparison. */
3285 /* E1 and E2 are for scratch. */
3293 if (TREE_SIDE_EFFECTS (op0))
3294 op0 = save_expr (op0);
3295 if (TREE_SIDE_EFFECTS (op1))
3296 op1 = save_expr (op1);
3301 && (!op0.pfn || op0.delta == op1.delta))
3303 The reason for the `!op0.pfn' bit is that a NULL
3304 pointer-to-member is any member with a zero PFN; the
3305 DELTA field is unspecified. */
3306 pfn0 = pfn_from_ptrmemfunc (op0);
3307 pfn1 = pfn_from_ptrmemfunc (op1);
3308 delta0 = build_ptrmemfunc_access_expr (op0,
3310 delta1 = build_ptrmemfunc_access_expr (op1,
3312 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
3313 e2 = cp_build_binary_op (EQ_EXPR,
3315 cp_convert (TREE_TYPE (pfn0),
3316 integer_zero_node));
3317 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
3318 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3319 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3320 if (code == EQ_EXPR)
3322 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3326 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3327 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3329 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3330 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3338 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3339 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3341 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3342 result_type = composite_pointer_type (type0, type1, op0, op1,
3350 if (TREE_CODE (orig_op0) == STRING_CST
3351 || TREE_CODE (orig_op1) == STRING_CST)
3352 warning (OPT_Wstring_literal_comparison,
3353 "comparison with string literal");
3355 build_type = boolean_type_node;
3356 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3357 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3359 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3360 result_type = composite_pointer_type (type0, type1, op0, op1,
3362 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3363 && integer_zerop (op1))
3364 result_type = type0;
3365 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3366 && integer_zerop (op0))
3367 result_type = type1;
3368 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3370 result_type = type0;
3371 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3373 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3375 result_type = type1;
3376 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3380 case UNORDERED_EXPR:
3387 build_type = integer_type_node;
3388 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3390 error ("unordered comparison on non-floating point argument");
3391 return error_mark_node;
3400 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3401 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3402 || code1 == COMPLEX_TYPE)))
3403 arithmetic_types_p = 1;
3406 arithmetic_types_p = 0;
3407 /* Vector arithmetic is only allowed when both sides are vectors. */
3408 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3410 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3411 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3414 binary_op_error (code);
3415 return error_mark_node;
3417 arithmetic_types_p = 1;
3420 /* Determine the RESULT_TYPE, if it is not already known. */
3422 && arithmetic_types_p
3423 && (shorten || common || short_compare))
3424 result_type = common_type (type0, type1);
3428 error ("invalid operands of types %qT and %qT to binary %qO",
3429 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3430 return error_mark_node;
3433 /* If we're in a template, the only thing we need to know is the
3435 if (processing_template_decl)
3436 return build2 (resultcode,
3437 build_type ? build_type : result_type,
3440 if (arithmetic_types_p)
3442 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3444 /* For certain operations (which identify themselves by shorten != 0)
3445 if both args were extended from the same smaller type,
3446 do the arithmetic in that type and then extend.
3448 shorten !=0 and !=1 indicates a bitwise operation.
3449 For them, this optimization is safe only if
3450 both args are zero-extended or both are sign-extended.
3451 Otherwise, we might change the result.
3452 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3453 but calculated in (unsigned short) it would be (unsigned short)-1. */
3455 if (shorten && none_complex)
3457 int unsigned0, unsigned1;
3458 tree arg0 = get_narrower (op0, &unsigned0);
3459 tree arg1 = get_narrower (op1, &unsigned1);
3460 /* UNS is 1 if the operation to be done is an unsigned one. */
3461 int uns = TYPE_UNSIGNED (result_type);
3464 final_type = result_type;
3466 /* Handle the case that OP0 does not *contain* a conversion
3467 but it *requires* conversion to FINAL_TYPE. */
3469 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3470 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
3471 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3472 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
3474 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3476 /* For bitwise operations, signedness of nominal type
3477 does not matter. Consider only how operands were extended. */
3481 /* Note that in all three cases below we refrain from optimizing
3482 an unsigned operation on sign-extended args.
3483 That would not be valid. */
3485 /* Both args variable: if both extended in same way
3486 from same width, do it in that width.
3487 Do it unsigned if args were zero-extended. */
3488 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3489 < TYPE_PRECISION (result_type))
3490 && (TYPE_PRECISION (TREE_TYPE (arg1))
3491 == TYPE_PRECISION (TREE_TYPE (arg0)))
3492 && unsigned0 == unsigned1
3493 && (unsigned0 || !uns))
3494 result_type = c_common_signed_or_unsigned_type
3495 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3496 else if (TREE_CODE (arg0) == INTEGER_CST
3497 && (unsigned1 || !uns)
3498 && (TYPE_PRECISION (TREE_TYPE (arg1))
3499 < TYPE_PRECISION (result_type))
3500 && (type = c_common_signed_or_unsigned_type
3501 (unsigned1, TREE_TYPE (arg1)),
3502 int_fits_type_p (arg0, type)))
3504 else if (TREE_CODE (arg1) == INTEGER_CST
3505 && (unsigned0 || !uns)
3506 && (TYPE_PRECISION (TREE_TYPE (arg0))
3507 < TYPE_PRECISION (result_type))
3508 && (type = c_common_signed_or_unsigned_type
3509 (unsigned0, TREE_TYPE (arg0)),
3510 int_fits_type_p (arg1, type)))
3514 /* Shifts can be shortened if shifting right. */
3519 tree arg0 = get_narrower (op0, &unsigned_arg);
3521 final_type = result_type;
3523 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3524 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
3526 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3527 /* We can shorten only if the shift count is less than the
3528 number of bits in the smaller type size. */
3529 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3530 /* If arg is sign-extended and then unsigned-shifted,
3531 we can simulate this with a signed shift in arg's type
3532 only if the extended result is at least twice as wide
3533 as the arg. Otherwise, the shift could use up all the
3534 ones made by sign-extension and bring in zeros.
3535 We can't optimize that case at all, but in most machines
3536 it never happens because available widths are 2**N. */
3537 && (!TYPE_UNSIGNED (final_type)
3539 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3540 <= TYPE_PRECISION (result_type))))
3542 /* Do an unsigned shift if the operand was zero-extended. */
3544 = c_common_signed_or_unsigned_type (unsigned_arg,
3546 /* Convert value-to-be-shifted to that type. */
3547 if (TREE_TYPE (op0) != result_type)
3548 op0 = cp_convert (result_type, op0);
3553 /* Comparison operations are shortened too but differently.
3554 They identify themselves by setting short_compare = 1. */
3558 /* Don't write &op0, etc., because that would prevent op0
3559 from being kept in a register.
3560 Instead, make copies of the our local variables and
3561 pass the copies by reference, then copy them back afterward. */
3562 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3563 enum tree_code xresultcode = resultcode;
3565 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3567 return cp_convert (boolean_type_node, val);
3568 op0 = xop0, op1 = xop1;
3570 resultcode = xresultcode;
3573 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3574 && warn_sign_compare
3575 /* Do not warn until the template is instantiated; we cannot
3576 bound the ranges of the arguments until that point. */
3577 && !processing_template_decl)
3579 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
3580 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3582 int unsignedp0, unsignedp1;
3583 tree primop0 = get_narrower (op0, &unsignedp0);
3584 tree primop1 = get_narrower (op1, &unsignedp1);
3586 /* Check for comparison of different enum types. */
3587 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3588 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3589 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3590 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3592 warning (0, "comparison between types %q#T and %q#T",
3593 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3596 /* Give warnings for comparisons between signed and unsigned
3597 quantities that may fail. */
3598 /* Do the checking based on the original operand trees, so that
3599 casts will be considered, but default promotions won't be. */
3601 /* Do not warn if the comparison is being done in a signed type,
3602 since the signed type will only be chosen if it can represent
3603 all the values of the unsigned type. */
3604 if (!TYPE_UNSIGNED (result_type))
3606 /* Do not warn if both operands are unsigned. */
3607 else if (op0_signed == op1_signed)
3609 /* Do not warn if the signed quantity is an unsuffixed
3610 integer literal (or some static constant expression
3611 involving such literals or a conditional expression
3612 involving such literals) and it is non-negative. */
3613 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3614 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3616 /* Do not warn if the comparison is an equality operation,
3617 the unsigned quantity is an integral constant and it does
3618 not use the most significant bit of result_type. */
3619 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3620 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3621 && int_fits_type_p (orig_op1, c_common_signed_type
3623 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3624 && int_fits_type_p (orig_op0, c_common_signed_type
3628 warning (0, "comparison between signed and unsigned integer expressions");
3630 /* Warn if two unsigned values are being compared in a size
3631 larger than their original size, and one (and only one) is the
3632 result of a `~' operator. This comparison will always fail.
3634 Also warn if one operand is a constant, and the constant does not
3635 have all bits set that are set in the ~ operand when it is
3638 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3639 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3641 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3642 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3643 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3644 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3646 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3649 HOST_WIDE_INT constant, mask;
3653 if (host_integerp (primop0, 0))
3656 unsignedp = unsignedp1;
3657 constant = tree_low_cst (primop0, 0);
3662 unsignedp = unsignedp0;
3663 constant = tree_low_cst (primop1, 0);
3666 bits = TYPE_PRECISION (TREE_TYPE (primop));
3667 if (bits < TYPE_PRECISION (result_type)
3668 && bits < HOST_BITS_PER_LONG && unsignedp)
3670 mask = (~ (HOST_WIDE_INT) 0) << bits;
3671 if ((mask & constant) != mask)
3672 warning (0, "comparison of promoted ~unsigned with constant");
3675 else if (unsignedp0 && unsignedp1
3676 && (TYPE_PRECISION (TREE_TYPE (primop0))
3677 < TYPE_PRECISION (result_type))
3678 && (TYPE_PRECISION (TREE_TYPE (primop1))
3679 < TYPE_PRECISION (result_type)))
3680 warning (0, "comparison of promoted ~unsigned with unsigned");
3685 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3686 Then the expression will be built.
3687 It will be given type FINAL_TYPE if that is nonzero;
3688 otherwise, it will be given type RESULT_TYPE. */
3690 /* Issue warnings about peculiar, but valid, uses of NULL. */
3691 if (/* It's reasonable to use pointer values as operands of &&
3692 and ||, so NULL is no exception. */
3693 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3694 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3695 (orig_op0 == null_node
3696 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3697 /* Or vice versa. */
3698 || (orig_op1 == null_node
3699 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3700 /* Or, both are NULL and the operation was not a comparison. */
3701 || (orig_op0 == null_node && orig_op1 == null_node
3702 && code != EQ_EXPR && code != NE_EXPR)))
3703 /* Some sort of arithmetic operation involving NULL was
3704 performed. Note that pointer-difference and pointer-addition
3705 have already been handled above, and so we don't end up here in
3707 warning (0, "NULL used in arithmetic");
3711 if (TREE_TYPE (op0) != result_type)
3712 op0 = cp_convert (result_type, op0);
3713 if (TREE_TYPE (op1) != result_type)
3714 op1 = cp_convert (result_type, op1);
3716 if (op0 == error_mark_node || op1 == error_mark_node)
3717 return error_mark_node;
3720 if (build_type == NULL_TREE)
3721 build_type = result_type;
3723 result = build2 (resultcode, build_type, op0, op1);
3724 result = fold_if_not_in_template (result);
3725 if (final_type != 0)
3726 result = cp_convert (final_type, result);
3730 /* Return a tree for the sum or difference (RESULTCODE says which)
3731 of pointer PTROP and integer INTOP. */
3734 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
3736 tree res_type = TREE_TYPE (ptrop);
3738 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3739 in certain circumstance (when it's valid to do so). So we need
3740 to make sure it's complete. We don't need to check here, if we
3741 can actually complete it at all, as those checks will be done in
3742 pointer_int_sum() anyway. */
3743 complete_type (TREE_TYPE (res_type));
3745 return pointer_int_sum (resultcode, ptrop,
3746 fold_if_not_in_template (intop));
3749 /* Return a tree for the difference of pointers OP0 and OP1.
3750 The resulting tree has type int. */
3753 pointer_diff (tree op0, tree op1, tree ptrtype)
3756 tree restype = ptrdiff_type_node;
3757 tree target_type = TREE_TYPE (ptrtype);
3759 if (!complete_type_or_else (target_type, NULL_TREE))
3760 return error_mark_node;
3762 if (pedantic || warn_pointer_arith)
3764 if (TREE_CODE (target_type) == VOID_TYPE)
3765 pedwarn ("ISO C++ forbids using pointer of type %<void *%> in subtraction");
3766 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3767 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3768 if (TREE_CODE (target_type) == METHOD_TYPE)
3769 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3772 /* First do the subtraction as integers;
3773 then drop through to build the divide operator. */
3775 op0 = cp_build_binary_op (MINUS_EXPR,
3776 cp_convert (restype, op0),
3777 cp_convert (restype, op1));
3779 /* This generates an error if op1 is a pointer to an incomplete type. */
3780 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3781 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3783 op1 = (TYPE_PTROB_P (ptrtype)
3784 ? size_in_bytes (target_type)
3785 : integer_one_node);
3787 /* Do the division. */
3789 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3790 return fold_if_not_in_template (result);
3793 /* Construct and perhaps optimize a tree representation
3794 for a unary operation. CODE, a tree_code, specifies the operation
3795 and XARG is the operand. */
3798 build_x_unary_op (enum tree_code code, tree xarg)
3800 tree orig_expr = xarg;
3804 if (processing_template_decl)
3806 if (type_dependent_expression_p (xarg))
3807 return build_min_nt (code, xarg, NULL_TREE);
3809 xarg = build_non_dependent_expr (xarg);
3814 /* [expr.unary.op] says:
3816 The address of an object of incomplete type can be taken.
3818 (And is just the ordinary address operator, not an overloaded
3819 "operator &".) However, if the type is a template
3820 specialization, we must complete the type at this point so that
3821 an overloaded "operator &" will be available if required. */
3822 if (code == ADDR_EXPR
3823 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3824 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
3825 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
3826 || (TREE_CODE (xarg) == OFFSET_REF)))
3827 /* Don't look for a function. */;
3829 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
3830 /*overloaded_p=*/NULL);
3831 if (!exp && code == ADDR_EXPR)
3833 /* A pointer to member-function can be formed only by saying
3835 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3836 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3838 if (TREE_CODE (xarg) != OFFSET_REF
3839 || !TYPE_P (TREE_OPERAND (xarg, 0)))
3841 error ("invalid use of %qE to form a pointer-to-member-function",
3843 if (TREE_CODE (xarg) != OFFSET_REF)
3844 inform (" a qualified-id is required");
3845 return error_mark_node;
3849 error ("parentheses around %qE cannot be used to form a"
3850 " pointer-to-member-function",
3852 PTRMEM_OK_P (xarg) = 1;
3856 if (TREE_CODE (xarg) == OFFSET_REF)
3858 ptrmem = PTRMEM_OK_P (xarg);
3860 if (!ptrmem && !flag_ms_extensions
3861 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3863 /* A single non-static member, make sure we don't allow a
3864 pointer-to-member. */
3865 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
3866 TREE_OPERAND (xarg, 0),
3867 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3868 PTRMEM_OK_P (xarg) = ptrmem;
3871 else if (TREE_CODE (xarg) == TARGET_EXPR)
3872 warning (0, "taking address of temporary");
3873 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3876 if (processing_template_decl && exp != error_mark_node)
3877 exp = build_min_non_dep (code, exp, orig_expr,
3878 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
3879 if (TREE_CODE (exp) == ADDR_EXPR)
3880 PTRMEM_OK_P (exp) = ptrmem;
3884 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3885 constants, where a null value is represented by an INTEGER_CST of
3889 cp_truthvalue_conversion (tree expr)
3891 tree type = TREE_TYPE (expr);
3892 if (TYPE_PTRMEM_P (type))
3893 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3895 return c_common_truthvalue_conversion (expr);
3898 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3901 condition_conversion (tree expr)
3904 if (processing_template_decl)
3906 t = perform_implicit_conversion (boolean_type_node, expr);
3907 t = fold_build_cleanup_point_expr (boolean_type_node, t);
3911 /* Return an ADDR_EXPR giving the address of T. This function
3912 attempts no optimizations or simplifications; it is a low-level
3916 build_address (tree t)
3920 if (error_operand_p (t) || !cxx_mark_addressable (t))
3921 return error_mark_node;
3923 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
3928 /* Return a NOP_EXPR converting EXPR to TYPE. */
3931 build_nop (tree type, tree expr)
3933 if (type == error_mark_node || error_operand_p (expr))
3935 return build1 (NOP_EXPR, type, expr);
3938 /* C++: Must handle pointers to members.
3940 Perhaps type instantiation should be extended to handle conversion
3941 from aggregates to types we don't yet know we want? (Or are those
3942 cases typically errors which should be reported?)
3944 NOCONVERT nonzero suppresses the default promotions
3945 (such as from short to int). */
3948 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3950 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3953 const char *errstring = NULL;
3955 const char *invalid_op_diag;
3957 if (arg == error_mark_node)
3958 return error_mark_node;
3960 if ((invalid_op_diag
3961 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
3966 error (invalid_op_diag);
3967 return error_mark_node;
3972 case UNARY_PLUS_EXPR:
3975 int flags = WANT_ARITH | WANT_ENUM;
3976 /* Unary plus (but not unary minus) is allowed on pointers. */
3977 if (code == UNARY_PLUS_EXPR)
3978 flags |= WANT_POINTER;
3979 arg = build_expr_type_conversion (flags, arg, true);
3981 errstring = (code == NEGATE_EXPR
3982 ? "wrong type argument to unary minus"
3983 : "wrong type argument to unary plus");
3986 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3987 arg = perform_integral_promotions (arg);
3989 /* Make sure the result is not an lvalue: a unary plus or minus
3990 expression is always a rvalue. */
3997 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4001 arg = default_conversion (arg);
4003 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
4005 errstring = "wrong type argument to bit-complement";
4006 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
4007 arg = perform_integral_promotions (arg);
4011 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4012 errstring = "wrong type argument to abs";
4013 else if (!noconvert)
4014 arg = default_conversion (arg);
4018 /* Conjugating a real value is a no-op, but allow it anyway. */
4019 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
4020 errstring = "wrong type argument to conjugation";
4021 else if (!noconvert)
4022 arg = default_conversion (arg);
4025 case TRUTH_NOT_EXPR:
4026 arg = perform_implicit_conversion (boolean_type_node, arg);
4027 val = invert_truthvalue (arg);
4028 if (arg != error_mark_node)
4030 errstring = "in argument to unary !";
4037 if (TREE_CODE (arg) == COMPLEX_CST)
4038 return TREE_REALPART (arg);
4039 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4041 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4042 return fold_if_not_in_template (arg);
4048 if (TREE_CODE (arg) == COMPLEX_CST)
4049 return TREE_IMAGPART (arg);
4050 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4052 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4053 return fold_if_not_in_template (arg);
4056 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4058 case PREINCREMENT_EXPR:
4059 case POSTINCREMENT_EXPR:
4060 case PREDECREMENT_EXPR:
4061 case POSTDECREMENT_EXPR:
4062 /* Handle complex lvalues (when permitted)
4063 by reduction to simpler cases. */
4065 val = unary_complex_lvalue (code, arg);
4069 /* Increment or decrement the real part of the value,
4070 and don't change the imaginary part. */
4071 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4075 arg = stabilize_reference (arg);
4076 real = build_unary_op (REALPART_EXPR, arg, 1);
4077 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
4078 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4079 build_unary_op (code, real, 1), imag);
4082 /* Report invalid types. */
4084 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4087 if (code == PREINCREMENT_EXPR)
4088 errstring ="no pre-increment operator for type";
4089 else if (code == POSTINCREMENT_EXPR)
4090 errstring ="no post-increment operator for type";
4091 else if (code == PREDECREMENT_EXPR)
4092 errstring ="no pre-decrement operator for type";
4094 errstring ="no post-decrement operator for type";
4098 /* Report something read-only. */
4100 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4101 || TREE_READONLY (arg))
4102 readonly_error (arg, ((code == PREINCREMENT_EXPR
4103 || code == POSTINCREMENT_EXPR)
4104 ? "increment" : "decrement"),
4109 tree result_type = TREE_TYPE (arg);
4111 arg = get_unwidened (arg, 0);
4112 argtype = TREE_TYPE (arg);
4114 /* ARM $5.2.5 last annotation says this should be forbidden. */
4115 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4116 pedwarn ("ISO C++ forbids %sing an enum",
4117 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4118 ? "increment" : "decrement");
4120 /* Compute the increment. */
4122 if (TREE_CODE (argtype) == POINTER_TYPE)
4124 tree type = complete_type (TREE_TYPE (argtype));
4126 if (!COMPLETE_OR_VOID_TYPE_P (type))
4127 error ("cannot %s a pointer to incomplete type %qT",
4128 ((code == PREINCREMENT_EXPR
4129 || code == POSTINCREMENT_EXPR)
4130 ? "increment" : "decrement"), TREE_TYPE (argtype));
4131 else if ((pedantic || warn_pointer_arith)
4132 && !TYPE_PTROB_P (argtype))
4133 pedwarn ("ISO C++ forbids %sing a pointer of type %qT",
4134 ((code == PREINCREMENT_EXPR
4135 || code == POSTINCREMENT_EXPR)
4136 ? "increment" : "decrement"), argtype);
4137 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4140 inc = integer_one_node;
4142 inc = cp_convert (argtype, inc);
4144 /* Handle incrementing a cast-expression. */
4146 switch (TREE_CODE (arg))
4151 case FIX_TRUNC_EXPR:
4152 case FIX_FLOOR_EXPR:
4153 case FIX_ROUND_EXPR:
4156 tree incremented, modify, value, compound;
4157 if (! lvalue_p (arg) && pedantic)
4158 pedwarn ("cast to non-reference type used as lvalue");
4159 arg = stabilize_reference (arg);
4160 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
4163 value = save_expr (arg);
4164 incremented = build2 (((code == PREINCREMENT_EXPR
4165 || code == POSTINCREMENT_EXPR)
4166 ? PLUS_EXPR : MINUS_EXPR),
4167 argtype, value, inc);
4169 modify = build_modify_expr (arg, NOP_EXPR, incremented);
4170 compound = build2 (COMPOUND_EXPR, TREE_TYPE (arg),
4173 /* Eliminate warning about unused result of + or -. */
4174 TREE_NO_WARNING (compound) = 1;
4182 /* Complain about anything else that is not a true lvalue. */
4183 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4184 || code == POSTINCREMENT_EXPR)
4185 ? lv_increment : lv_decrement)))
4186 return error_mark_node;
4188 /* Forbid using -- on `bool'. */
4189 if (TREE_TYPE (arg) == boolean_type_node)
4191 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4193 error ("invalid use of %<--%> on bool variable %qD", arg);
4194 return error_mark_node;
4196 val = boolean_increment (code, arg);
4199 val = build2 (code, TREE_TYPE (arg), arg, inc);
4201 TREE_SIDE_EFFECTS (val) = 1;
4202 return cp_convert (result_type, val);
4206 /* Note that this operation never does default_conversion
4207 regardless of NOCONVERT. */
4209 argtype = lvalue_type (arg);
4211 if (TREE_CODE (arg) == OFFSET_REF)
4214 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4216 tree type = build_pointer_type (TREE_TYPE (argtype));
4217 arg = build1 (CONVERT_EXPR, type, arg);
4220 else if (pedantic && DECL_MAIN_P (arg))
4222 pedwarn ("ISO C++ forbids taking address of function %<::main%>");
4224 /* Let &* cancel out to simplify resulting code. */
4225 if (TREE_CODE (arg) == INDIRECT_REF)
4227 /* We don't need to have `current_class_ptr' wrapped in a
4228 NON_LVALUE_EXPR node. */
4229 if (arg == current_class_ref)
4230 return current_class_ptr;
4232 arg = TREE_OPERAND (arg, 0);
4233 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4235 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4236 arg = build1 (CONVERT_EXPR, type, arg);
4239 /* Don't let this be an lvalue. */
4244 /* Uninstantiated types are all functions. Taking the
4245 address of a function is a no-op, so just return the
4248 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4249 || !IDENTIFIER_OPNAME_P (arg));
4251 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4252 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4254 /* They're trying to take the address of a unique non-static
4255 member function. This is ill-formed (except in MS-land),
4256 but let's try to DTRT.
4257 Note: We only handle unique functions here because we don't
4258 want to complain if there's a static overload; non-unique
4259 cases will be handled by instantiate_type. But we need to
4260 handle this case here to allow casts on the resulting PMF.
4261 We could defer this in non-MS mode, but it's easier to give
4262 a useful error here. */
4264 /* Inside constant member functions, the `this' pointer
4265 contains an extra const qualifier. TYPE_MAIN_VARIANT
4266 is used here to remove this const from the diagnostics
4267 and the created OFFSET_REF. */
4268 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4269 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4272 if (! flag_ms_extensions)
4274 tree name = DECL_NAME (fn);
4275 if (current_class_type
4276 && TREE_OPERAND (arg, 0) == current_class_ref)
4277 /* An expression like &memfn. */
4278 pedwarn ("ISO C++ forbids taking the address of an unqualified"
4279 " or parenthesized non-static member function to form"
4280 " a pointer to member function. Say %<&%T::%D%>",
4283 pedwarn ("ISO C++ forbids taking the address of a bound member"
4284 " function to form a pointer to member function."
4288 arg = build_offset_ref (base, fn, /*address_p=*/true);
4292 if (type_unknown_p (arg))
4293 return build1 (ADDR_EXPR, unknown_type_node, arg);
4295 /* Handle complex lvalues (when permitted)
4296 by reduction to simpler cases. */
4297 val = unary_complex_lvalue (code, arg);
4301 switch (TREE_CODE (arg))
4306 case FIX_TRUNC_EXPR:
4307 case FIX_FLOOR_EXPR:
4308 case FIX_ROUND_EXPR:
4310 if (! lvalue_p (arg) && pedantic)
4311 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4315 arg = OVL_CURRENT (arg);
4319 /* Turn a reference to a non-static data member into a
4320 pointer-to-member. */
4325 if (!PTRMEM_OK_P (arg))
4326 return build_unary_op (code, arg, 0);
4328 t = TREE_OPERAND (arg, 1);
4329 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4331 error ("cannot create pointer to reference member %qD", t);
4332 return error_mark_node;
4335 type = build_ptrmem_type (context_for_name_lookup (t),
4337 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4345 /* Anything not already handled and not a true memory reference
4347 if (TREE_CODE (argtype) != FUNCTION_TYPE
4348 && TREE_CODE (argtype) != METHOD_TYPE
4349 && TREE_CODE (arg) != OFFSET_REF
4350 && !lvalue_or_else (arg, lv_addressof))
4351 return error_mark_node;
4353 if (argtype != error_mark_node)
4354 argtype = build_pointer_type (argtype);
4356 /* In a template, we are processing a non-dependent expression
4357 so we can just form an ADDR_EXPR with the correct type. */
4358 if (processing_template_decl)
4360 val = build_address (arg);
4361 if (TREE_CODE (arg) == OFFSET_REF)
4362 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4366 if (TREE_CODE (arg) != COMPONENT_REF)
4368 val = build_address (arg);
4369 if (TREE_CODE (arg) == OFFSET_REF)
4370 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4372 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4374 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4376 /* We can only get here with a single static member
4378 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4379 && DECL_STATIC_FUNCTION_P (fn));
4381 val = build_address (fn);
4382 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4383 /* Do not lose object's side effects. */
4384 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4385 TREE_OPERAND (arg, 0), val);
4387 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4389 error ("attempt to take address of bit-field structure member %qD",
4390 TREE_OPERAND (arg, 1));
4391 return error_mark_node;
4395 tree object = TREE_OPERAND (arg, 0);
4396 tree field = TREE_OPERAND (arg, 1);
4397 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4398 (TREE_TYPE (object), decl_type_context (field)));
4399 val = build_address (arg);
4402 if (TREE_CODE (argtype) == POINTER_TYPE
4403 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4405 build_ptrmemfunc_type (argtype);
4406 val = build_ptrmemfunc (argtype, val, 0,
4407 /*c_cast_p=*/false);
4419 argtype = TREE_TYPE (arg);
4420 return fold_if_not_in_template (build1 (code, argtype, arg));
4423 error ("%s", errstring);
4424 return error_mark_node;
4427 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4428 for certain kinds of expressions which are not really lvalues
4429 but which we can accept as lvalues.
4431 If ARG is not a kind of expression we can handle, return
4435 unary_complex_lvalue (enum tree_code code, tree arg)
4437 /* Inside a template, making these kinds of adjustments is
4438 pointless; we are only concerned with the type of the
4440 if (processing_template_decl)
4443 /* Handle (a, b) used as an "lvalue". */
4444 if (TREE_CODE (arg) == COMPOUND_EXPR)
4446 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4447 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4448 TREE_OPERAND (arg, 0), real_result);
4451 /* Handle (a ? b : c) used as an "lvalue". */
4452 if (TREE_CODE (arg) == COND_EXPR
4453 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4454 return rationalize_conditional_expr (code, arg);
4456 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4457 if (TREE_CODE (arg) == MODIFY_EXPR
4458 || TREE_CODE (arg) == PREINCREMENT_EXPR
4459 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4461 tree lvalue = TREE_OPERAND (arg, 0);
4462 if (TREE_SIDE_EFFECTS (lvalue))
4464 lvalue = stabilize_reference (lvalue);
4465 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4466 lvalue, TREE_OPERAND (arg, 1));
4468 return unary_complex_lvalue
4469 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4472 if (code != ADDR_EXPR)
4475 /* Handle (a = b) used as an "lvalue" for `&'. */
4476 if (TREE_CODE (arg) == MODIFY_EXPR
4477 || TREE_CODE (arg) == INIT_EXPR)
4479 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4480 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4482 TREE_NO_WARNING (arg) = 1;
4486 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4487 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4488 || TREE_CODE (arg) == OFFSET_REF)
4491 /* We permit compiler to make function calls returning
4492 objects of aggregate type look like lvalues. */
4496 if (TREE_CODE (targ) == SAVE_EXPR)
4497 targ = TREE_OPERAND (targ, 0);
4499 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4501 if (TREE_CODE (arg) == SAVE_EXPR)
4504 targ = build_cplus_new (TREE_TYPE (arg), arg);
4505 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4508 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4509 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4510 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4513 /* Don't let anything else be handled specially. */
4517 /* Mark EXP saying that we need to be able to take the
4518 address of it; it should not be allocated in a register.
4519 Value is true if successful.
4521 C++: we do not allow `current_class_ptr' to be addressable. */
4524 cxx_mark_addressable (tree exp)
4529 switch (TREE_CODE (x))
4536 x = TREE_OPERAND (x, 0);
4540 if (x == current_class_ptr)
4542 error ("cannot take the address of %<this%>, which is an rvalue expression");
4543 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4549 /* Caller should not be trying to mark initialized
4550 constant fields addressable. */
4551 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4552 || DECL_IN_AGGR_P (x) == 0
4554 || DECL_EXTERNAL (x));
4559 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4560 && !DECL_ARTIFICIAL (x))
4562 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4565 ("address of explicit register variable %qD requested", x);
4568 else if (extra_warnings)
4570 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
4572 TREE_ADDRESSABLE (x) = 1;
4576 TREE_ADDRESSABLE (x) = 1;
4580 TREE_ADDRESSABLE (x) = 1;
4584 TREE_ADDRESSABLE (x) = 1;
4585 cxx_mark_addressable (TREE_OPERAND (x, 0));
4593 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4596 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4598 tree orig_ifexp = ifexp;
4599 tree orig_op1 = op1;
4600 tree orig_op2 = op2;
4603 if (processing_template_decl)
4605 /* The standard says that the expression is type-dependent if
4606 IFEXP is type-dependent, even though the eventual type of the
4607 expression doesn't dependent on IFEXP. */
4608 if (type_dependent_expression_p (ifexp)
4609 /* As a GNU extension, the middle operand may be omitted. */
4610 || (op1 && type_dependent_expression_p (op1))
4611 || type_dependent_expression_p (op2))
4612 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4613 ifexp = build_non_dependent_expr (ifexp);
4615 op1 = build_non_dependent_expr (op1);
4616 op2 = build_non_dependent_expr (op2);
4619 expr = build_conditional_expr (ifexp, op1, op2);
4620 if (processing_template_decl && expr != error_mark_node)
4621 return build_min_non_dep (COND_EXPR, expr,
4622 orig_ifexp, orig_op1, orig_op2);
4626 /* Given a list of expressions, return a compound expression
4627 that performs them all and returns the value of the last of them. */
4629 tree build_x_compound_expr_from_list (tree list, const char *msg)
4631 tree expr = TREE_VALUE (list);
4633 if (TREE_CHAIN (list))
4636 pedwarn ("%s expression list treated as compound expression", msg);
4638 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4639 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4645 /* Handle overloading of the ',' operator when needed. */
4648 build_x_compound_expr (tree op1, tree op2)
4651 tree orig_op1 = op1;
4652 tree orig_op2 = op2;
4654 if (processing_template_decl)
4656 if (type_dependent_expression_p (op1)
4657 || type_dependent_expression_p (op2))
4658 return build_min_nt (COMPOUND_EXPR, op1, op2);
4659 op1 = build_non_dependent_expr (op1);
4660 op2 = build_non_dependent_expr (op2);
4663 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4664 /*overloaded_p=*/NULL);
4666 result = build_compound_expr (op1, op2);
4668 if (processing_template_decl && result != error_mark_node)
4669 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4674 /* Build a compound expression. */
4677 build_compound_expr (tree lhs, tree rhs)
4679 lhs = convert_to_void (lhs, "left-hand operand of comma");
4681 if (lhs == error_mark_node || rhs == error_mark_node)
4682 return error_mark_node;
4684 if (TREE_CODE (rhs) == TARGET_EXPR)
4686 /* If the rhs is a TARGET_EXPR, then build the compound
4687 expression inside the target_expr's initializer. This
4688 helps the compiler to eliminate unnecessary temporaries. */
4689 tree init = TREE_OPERAND (rhs, 1);
4691 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4692 TREE_OPERAND (rhs, 1) = init;
4697 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4700 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
4701 casts away constness. DIAG_FN gives the function to call if we
4702 need to issue a diagnostic; if it is NULL, no diagnostic will be
4703 issued. DESCRIPTION explains what operation is taking place. */
4706 check_for_casting_away_constness (tree src_type, tree dest_type,
4707 void (*diag_fn)(const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2),
4708 const char *description)
4710 if (diag_fn && casts_away_constness (src_type, dest_type))
4711 diag_fn ("%s from type %qT to type %qT casts away constness",
4712 description, src_type, dest_type);
4715 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
4716 (another pointer-to-member type in the same hierarchy) and return
4717 the converted expression. If ALLOW_INVERSE_P is permitted, a
4718 pointer-to-derived may be converted to pointer-to-base; otherwise,
4719 only the other direction is permitted. If C_CAST_P is true, this
4720 conversion is taking place as part of a C-style cast. */
4723 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
4726 if (TYPE_PTRMEM_P (type))
4730 if (TREE_CODE (expr) == PTRMEM_CST)
4731 expr = cplus_expand_constant (expr);
4732 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
4733 TYPE_PTRMEM_CLASS_TYPE (type),
4736 if (!integer_zerop (delta))
4737 expr = cp_build_binary_op (PLUS_EXPR,
4738 build_nop (ptrdiff_type_node, expr),
4740 return build_nop (type, expr);
4743 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4744 allow_inverse_p, c_cast_p);
4747 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
4748 a version of EXPR that has TREE_OVERFLOW and/or TREE_CONSTANT_OVERFLOW
4749 set iff they are set in ORIG. Otherwise, return EXPR unchanged. */
4752 ignore_overflows (tree expr, tree orig)
4754 if (TREE_CODE (expr) == INTEGER_CST
4755 && CONSTANT_CLASS_P (orig)
4756 && TREE_CODE (orig) != STRING_CST
4757 && (TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig)
4758 || TREE_CONSTANT_OVERFLOW (expr)
4759 != TREE_CONSTANT_OVERFLOW (orig)))
4761 if (!TREE_OVERFLOW (orig) && !TREE_CONSTANT_OVERFLOW (orig))
4762 /* Ensure constant sharing. */
4763 expr = build_int_cst_wide (TREE_TYPE (expr),
4764 TREE_INT_CST_LOW (expr),
4765 TREE_INT_CST_HIGH (expr));
4768 /* Avoid clobbering a shared constant. */
4769 expr = copy_node (expr);
4770 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
4771 TREE_CONSTANT_OVERFLOW (expr)
4772 = TREE_CONSTANT_OVERFLOW (orig);
4778 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
4779 this static_cast is being attempted as one of the possible casts
4780 allowed by a C-style cast. (In that case, accessibility of base
4781 classes is not considered, and it is OK to cast away
4782 constness.) Return the result of the cast. *VALID_P is set to
4783 indicate whether or not the cast was valid. */
4786 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
4792 void (*diag_fn)(const char*, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
4795 /* Assume the cast is valid. */
4798 intype = TREE_TYPE (expr);
4800 /* Save casted types in the function's used types hash table. */
4801 used_types_insert (type);
4803 /* Determine what to do when casting away constness. */
4806 /* C-style casts are allowed to cast away constness. With
4807 WARN_CAST_QUAL, we still want to issue a warning. */
4808 diag_fn = warn_cast_qual ? warning0 : NULL;
4813 /* A static_cast may not cast away constness. */
4815 desc = "static_cast";
4818 /* [expr.static.cast]
4820 An lvalue of type "cv1 B", where B is a class type, can be cast
4821 to type "reference to cv2 D", where D is a class derived (clause
4822 _class.derived_) from B, if a valid standard conversion from
4823 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4824 same cv-qualification as, or greater cv-qualification than, cv1,
4825 and B is not a virtual base class of D. */
4826 /* We check this case before checking the validity of "TYPE t =
4827 EXPR;" below because for this case:
4830 struct D : public B { D(const B&); };
4832 void f() { static_cast<const D&>(b); }
4834 we want to avoid constructing a new D. The standard is not
4835 completely clear about this issue, but our interpretation is
4836 consistent with other compilers. */
4837 if (TREE_CODE (type) == REFERENCE_TYPE
4838 && CLASS_TYPE_P (TREE_TYPE (type))
4839 && CLASS_TYPE_P (intype)
4840 && real_lvalue_p (expr)
4841 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4842 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4843 build_pointer_type (TYPE_MAIN_VARIANT
4844 (TREE_TYPE (type))))
4846 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
4850 /* There is a standard conversion from "D*" to "B*" even if "B"
4851 is ambiguous or inaccessible. If this is really a
4852 static_cast, then we check both for inaccessibility and
4853 ambiguity. However, if this is a static_cast being performed
4854 because the user wrote a C-style cast, then accessibility is
4856 base = lookup_base (TREE_TYPE (type), intype,
4857 c_cast_p ? ba_unique : ba_check,
4860 /* Convert from "B*" to "D*". This function will check that "B"
4861 is not a virtual base of "D". */
4862 expr = build_base_path (MINUS_EXPR, build_address (expr),
4863 base, /*nonnull=*/false);
4864 /* Convert the pointer to a reference -- but then remember that
4865 there are no expressions with reference type in C++. */
4866 return convert_from_reference (build_nop (type, expr));
4871 /* [expr.static.cast]
4873 An expression e can be explicitly converted to a type T using a
4874 static_cast of the form static_cast<T>(e) if the declaration T
4875 t(e);" is well-formed, for some invented temporary variable
4877 result = perform_direct_initialization_if_possible (type, expr,
4881 result = convert_from_reference (result);
4883 /* Ignore any integer overflow caused by the cast. */
4884 result = ignore_overflows (result, orig);
4886 /* [expr.static.cast]
4888 If T is a reference type, the result is an lvalue; otherwise,
4889 the result is an rvalue. */
4890 if (TREE_CODE (type) != REFERENCE_TYPE)
4891 result = rvalue (result);
4895 /* [expr.static.cast]
4897 Any expression can be explicitly converted to type cv void. */
4898 if (TREE_CODE (type) == VOID_TYPE)
4899 return convert_to_void (expr, /*implicit=*/NULL);
4901 /* [expr.static.cast]
4903 The inverse of any standard conversion sequence (clause _conv_),
4904 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4905 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4906 (_conv.bool_) conversions, can be performed explicitly using
4907 static_cast subject to the restriction that the explicit
4908 conversion does not cast away constness (_expr.const.cast_), and
4909 the following additional rules for specific cases: */
4910 /* For reference, the conversions not excluded are: integral
4911 promotions, floating point promotion, integral conversions,
4912 floating point conversions, floating-integral conversions,
4913 pointer conversions, and pointer to member conversions. */
4916 A value of integral _or enumeration_ type can be explicitly
4917 converted to an enumeration type. */
4918 /* The effect of all that is that any conversion between any two
4919 types which are integral, floating, or enumeration types can be
4921 if ((INTEGRAL_TYPE_P (type) || SCALAR_FLOAT_TYPE_P (type))
4922 && (INTEGRAL_TYPE_P (intype) || SCALAR_FLOAT_TYPE_P (intype)))
4924 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
4926 /* Ignore any integer overflow caused by the cast. */
4927 expr = ignore_overflows (expr, orig);
4931 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4932 && CLASS_TYPE_P (TREE_TYPE (type))
4933 && CLASS_TYPE_P (TREE_TYPE (intype))
4934 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4935 (TREE_TYPE (intype))),
4936 build_pointer_type (TYPE_MAIN_VARIANT
4937 (TREE_TYPE (type)))))
4942 check_for_casting_away_constness (intype, type, diag_fn, desc);
4943 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
4944 c_cast_p ? ba_unique : ba_check,
4946 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4949 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4950 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4957 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4958 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4960 if (TYPE_PTRMEM_P (type))
4962 t1 = (build_ptrmem_type
4964 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4965 t2 = (build_ptrmem_type
4967 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4974 if (can_convert (t1, t2))
4977 check_for_casting_away_constness (intype, type, diag_fn,
4979 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
4984 /* [expr.static.cast]
4986 An rvalue of type "pointer to cv void" can be explicitly
4987 converted to a pointer to object type. A value of type pointer
4988 to object converted to "pointer to cv void" and back to the
4989 original pointer type will have its original value. */
4990 if (TREE_CODE (intype) == POINTER_TYPE
4991 && VOID_TYPE_P (TREE_TYPE (intype))
4992 && TYPE_PTROB_P (type))
4995 check_for_casting_away_constness (intype, type, diag_fn, desc);
4996 return build_nop (type, expr);
5000 return error_mark_node;
5003 /* Return an expression representing static_cast<TYPE>(EXPR). */
5006 build_static_cast (tree type, tree expr)
5011 if (type == error_mark_node || expr == error_mark_node)
5012 return error_mark_node;
5014 if (processing_template_decl)
5016 expr = build_min (STATIC_CAST_EXPR, type, expr);
5017 /* We don't know if it will or will not have side effects. */
5018 TREE_SIDE_EFFECTS (expr) = 1;
5019 return convert_from_reference (expr);
5022 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5023 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5024 if (TREE_CODE (type) != REFERENCE_TYPE
5025 && TREE_CODE (expr) == NOP_EXPR
5026 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5027 expr = TREE_OPERAND (expr, 0);
5029 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p);
5033 error ("invalid static_cast from type %qT to type %qT",
5034 TREE_TYPE (expr), type);
5035 return error_mark_node;
5038 /* EXPR is an expression with member function or pointer-to-member
5039 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5040 not permitted by ISO C++, but we accept it in some modes. If we
5041 are not in one of those modes, issue a diagnostic. Return the
5042 converted expression. */
5045 convert_member_func_to_ptr (tree type, tree expr)
5050 intype = TREE_TYPE (expr);
5051 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
5052 || TREE_CODE (intype) == METHOD_TYPE);
5054 if (pedantic || warn_pmf2ptr)
5055 pedwarn ("converting from %qT to %qT", intype, type);
5057 if (TREE_CODE (intype) == METHOD_TYPE)
5058 expr = build_addr_func (expr);
5059 else if (TREE_CODE (expr) == PTRMEM_CST)
5060 expr = build_address (PTRMEM_CST_MEMBER (expr));
5063 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
5064 decl = build_address (decl);
5065 expr = get_member_function_from_ptrfunc (&decl, expr);
5068 return build_nop (type, expr);
5071 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5072 If C_CAST_P is true, this reinterpret cast is being done as part of
5073 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5074 indicate whether or not reinterpret_cast was valid. */
5077 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5082 /* Assume the cast is invalid. */
5086 if (type == error_mark_node || error_operand_p (expr))
5087 return error_mark_node;
5089 intype = TREE_TYPE (expr);
5091 /* Save casted types in the function's used types hash table. */
5092 used_types_insert (type);
5094 /* [expr.reinterpret.cast]
5095 An lvalue expression of type T1 can be cast to the type
5096 "reference to T2" if an expression of type "pointer to T1" can be
5097 explicitly converted to the type "pointer to T2" using a
5098 reinterpret_cast. */
5099 if (TREE_CODE (type) == REFERENCE_TYPE)
5101 if (! real_lvalue_p (expr))
5103 error ("invalid cast of an rvalue expression of type "
5106 return error_mark_node;
5109 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5110 "B" are related class types; the reinterpret_cast does not
5111 adjust the pointer. */
5112 if (TYPE_PTR_P (intype)
5113 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5114 COMPARE_BASE | COMPARE_DERIVED)))
5115 warning (0, "casting %qT to %qT does not dereference pointer",
5118 expr = build_unary_op (ADDR_EXPR, expr, 0);
5119 if (expr != error_mark_node)
5120 expr = build_reinterpret_cast_1
5121 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5123 if (expr != error_mark_node)
5124 expr = build_indirect_ref (expr, 0);
5128 /* As a G++ extension, we consider conversions from member
5129 functions, and pointers to member functions to
5130 pointer-to-function and pointer-to-void types. If
5131 -Wno-pmf-conversions has not been specified,
5132 convert_member_func_to_ptr will issue an error message. */
5133 if ((TYPE_PTRMEMFUNC_P (intype)
5134 || TREE_CODE (intype) == METHOD_TYPE)
5135 && TYPE_PTR_P (type)
5136 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5137 || VOID_TYPE_P (TREE_TYPE (type))))
5138 return convert_member_func_to_ptr (type, expr);
5140 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5141 array-to-pointer, and function-to-pointer conversions are
5143 expr = decay_conversion (expr);
5145 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5146 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5147 if (TREE_CODE (expr) == NOP_EXPR
5148 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5149 expr = TREE_OPERAND (expr, 0);
5151 if (error_operand_p (expr))
5152 return error_mark_node;
5154 intype = TREE_TYPE (expr);
5156 /* [expr.reinterpret.cast]
5157 A pointer can be converted to any integral type large enough to
5159 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5161 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5162 pedwarn ("cast from %qT to %qT loses precision",
5165 /* [expr.reinterpret.cast]
5166 A value of integral or enumeration type can be explicitly
5167 converted to a pointer. */
5168 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5171 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5172 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5173 return fold_if_not_in_template (build_nop (type, expr));
5174 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5175 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5180 check_for_casting_away_constness (intype, type, error,
5181 "reinterpret_cast");
5182 /* Warn about possible alignment problems. */
5183 if (STRICT_ALIGNMENT && warn_cast_align
5184 && !VOID_TYPE_P (type)
5185 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5186 && COMPLETE_TYPE_P (TREE_TYPE (type))
5187 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5188 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5189 warning (0, "cast from %qT to %qT increases required alignment of "
5193 /* We need to strip nops here, because the frontend likes to
5194 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5196 strict_aliasing_warning (intype, type, sexpr);
5198 return fold_if_not_in_template (build_nop (type, expr));
5200 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5201 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5204 /* Only issue a warning, as we have always supported this
5205 where possible, and it is necessary in some cases. DR 195
5206 addresses this issue, but as of 2004/10/26 is still in
5208 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5209 return fold_if_not_in_template (build_nop (type, expr));
5211 else if (TREE_CODE (type) == VECTOR_TYPE)
5212 return fold_if_not_in_template (convert_to_vector (type, expr));
5213 else if (TREE_CODE (intype) == VECTOR_TYPE)
5214 return fold_if_not_in_template (convert_to_integer (type, expr));
5219 error ("invalid cast from type %qT to type %qT", intype, type);
5220 return error_mark_node;
5223 return cp_convert (type, expr);
5227 build_reinterpret_cast (tree type, tree expr)
5229 if (type == error_mark_node || expr == error_mark_node)
5230 return error_mark_node;
5232 if (processing_template_decl)
5234 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5236 if (!TREE_SIDE_EFFECTS (t)
5237 && type_dependent_expression_p (expr))
5238 /* There might turn out to be side effects inside expr. */
5239 TREE_SIDE_EFFECTS (t) = 1;
5240 return convert_from_reference (t);
5243 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5247 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5248 return an appropriate expression. Otherwise, return
5249 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5250 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5251 performing a C-style cast, its value upon return will indicate
5252 whether or not the conversion succeeded. */
5255 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5259 tree reference_type;
5261 /* Callers are responsible for handling error_mark_node as a
5262 destination type. */
5263 gcc_assert (dst_type != error_mark_node);
5264 /* In a template, callers should be building syntactic
5265 representations of casts, not using this machinery. */
5266 gcc_assert (!processing_template_decl);
5268 /* Assume the conversion is invalid. */
5272 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5275 error ("invalid use of const_cast with type %qT, "
5276 "which is not a pointer, "
5277 "reference, nor a pointer-to-data-member type", dst_type);
5278 return error_mark_node;
5281 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5284 error ("invalid use of const_cast with type %qT, which is a pointer "
5285 "or reference to a function type", dst_type);
5286 return error_mark_node;
5289 /* Save casted types in the function's used types hash table. */
5290 used_types_insert (dst_type);
5292 src_type = TREE_TYPE (expr);
5293 /* Expressions do not really have reference types. */
5294 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5295 src_type = TREE_TYPE (src_type);
5297 /* [expr.const.cast]
5299 An lvalue of type T1 can be explicitly converted to an lvalue of
5300 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5301 types) if a pointer to T1 can be explicitly converted to the type
5302 pointer to T2 using a const_cast. */
5303 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5305 reference_type = dst_type;
5306 if (! real_lvalue_p (expr))
5309 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5310 src_type, dst_type);
5311 return error_mark_node;
5313 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5314 src_type = build_pointer_type (src_type);
5318 reference_type = NULL_TREE;
5319 /* If the destination type is not a reference type, the
5320 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5321 conversions are performed. */
5322 src_type = type_decays_to (src_type);
5323 if (src_type == error_mark_node)
5324 return error_mark_node;
5327 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5328 && comp_ptr_ttypes_const (dst_type, src_type))
5333 /* This cast is actually a C-style cast. Issue a warning if
5334 the user is making a potentially unsafe cast. */
5336 check_for_casting_away_constness (src_type, dst_type,
5342 expr = build_unary_op (ADDR_EXPR, expr, 0);
5343 expr = build_nop (reference_type, expr);
5344 return convert_from_reference (expr);
5348 expr = decay_conversion (expr);
5349 /* build_c_cast puts on a NOP_EXPR to make the result not an
5350 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5351 non-lvalue context. */
5352 if (TREE_CODE (expr) == NOP_EXPR
5353 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5354 expr = TREE_OPERAND (expr, 0);
5355 return build_nop (dst_type, expr);
5360 error ("invalid const_cast from type %qT to type %qT",
5361 src_type, dst_type);
5362 return error_mark_node;
5366 build_const_cast (tree type, tree expr)
5368 if (type == error_mark_node || error_operand_p (expr))
5369 return error_mark_node;
5371 if (processing_template_decl)
5373 tree t = build_min (CONST_CAST_EXPR, type, expr);
5375 if (!TREE_SIDE_EFFECTS (t)
5376 && type_dependent_expression_p (expr))
5377 /* There might turn out to be side effects inside expr. */
5378 TREE_SIDE_EFFECTS (t) = 1;
5379 return convert_from_reference (t);
5382 return build_const_cast_1 (type, expr, /*complain=*/true,
5386 /* Build an expression representing an explicit C-style cast to type
5387 TYPE of expression EXPR. */
5390 build_c_cast (tree type, tree expr)
5396 if (type == error_mark_node || error_operand_p (expr))
5397 return error_mark_node;
5399 if (processing_template_decl)
5401 tree t = build_min (CAST_EXPR, type,
5402 tree_cons (NULL_TREE, value, NULL_TREE));
5403 /* We don't know if it will or will not have side effects. */
5404 TREE_SIDE_EFFECTS (t) = 1;
5405 return convert_from_reference (t);
5408 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5409 'Class') should always be retained, because this information aids
5410 in method lookup. */
5411 if (objc_is_object_ptr (type)
5412 && objc_is_object_ptr (TREE_TYPE (expr)))
5413 return build_nop (type, expr);
5415 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5416 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5417 if (TREE_CODE (type) != REFERENCE_TYPE
5418 && TREE_CODE (value) == NOP_EXPR
5419 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5420 value = TREE_OPERAND (value, 0);
5422 if (TREE_CODE (type) == ARRAY_TYPE)
5424 /* Allow casting from T1* to T2[] because Cfront allows it.
5425 NIHCL uses it. It is not valid ISO C++ however. */
5426 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5428 pedwarn ("ISO C++ forbids casting to an array type %qT", type);
5429 type = build_pointer_type (TREE_TYPE (type));
5433 error ("ISO C++ forbids casting to an array type %qT", type);
5434 return error_mark_node;
5438 if (TREE_CODE (type) == FUNCTION_TYPE
5439 || TREE_CODE (type) == METHOD_TYPE)
5441 error ("invalid cast to function type %qT", type);
5442 return error_mark_node;
5445 /* A C-style cast can be a const_cast. */
5446 result = build_const_cast_1 (type, value, /*complain=*/false,
5451 /* Or a static cast. */
5452 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5454 /* Or a reinterpret_cast. */
5456 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5458 /* The static_cast or reinterpret_cast may be followed by a
5461 /* A valid cast may result in errors if, for example, a
5462 conversion to am ambiguous base class is required. */
5463 && !error_operand_p (result))
5467 /* Non-class rvalues always have cv-unqualified type. */
5468 if (!CLASS_TYPE_P (type))
5469 type = TYPE_MAIN_VARIANT (type);
5470 result_type = TREE_TYPE (result);
5471 if (!CLASS_TYPE_P (result_type))
5472 result_type = TYPE_MAIN_VARIANT (result_type);
5473 /* If the type of RESULT does not match TYPE, perform a
5474 const_cast to make it match. If the static_cast or
5475 reinterpret_cast succeeded, we will differ by at most
5476 cv-qualification, so the follow-on const_cast is guaranteed
5478 if (!same_type_p (non_reference (type), non_reference (result_type)))
5480 result = build_const_cast_1 (type, result, false, &valid_p);
5481 gcc_assert (valid_p);
5486 return error_mark_node;
5489 /* Build an assignment expression of lvalue LHS from value RHS.
5490 MODIFYCODE is the code for a binary operator that we use
5491 to combine the old value of LHS with RHS to get the new value.
5492 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5494 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5497 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5501 tree lhstype = TREE_TYPE (lhs);
5502 tree olhstype = lhstype;
5503 tree olhs = NULL_TREE;
5504 bool plain_assign = (modifycode == NOP_EXPR);
5506 /* Avoid duplicate error messages from operands that had errors. */
5507 if (error_operand_p (lhs) || error_operand_p (rhs))
5508 return error_mark_node;
5510 /* Handle control structure constructs used as "lvalues". */
5511 switch (TREE_CODE (lhs))
5513 /* Handle --foo = 5; as these are valid constructs in C++. */
5514 case PREDECREMENT_EXPR:
5515 case PREINCREMENT_EXPR:
5516 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5517 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5518 stabilize_reference (TREE_OPERAND (lhs, 0)),
5519 TREE_OPERAND (lhs, 1));
5520 return build2 (COMPOUND_EXPR, lhstype,
5522 build_modify_expr (TREE_OPERAND (lhs, 0),
5525 /* Handle (a, b) used as an "lvalue". */
5527 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
5529 if (newrhs == error_mark_node)
5530 return error_mark_node;
5531 return build2 (COMPOUND_EXPR, lhstype,
5532 TREE_OPERAND (lhs, 0), newrhs);
5535 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5536 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5537 stabilize_reference (TREE_OPERAND (lhs, 0)),
5538 TREE_OPERAND (lhs, 1));
5539 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
5540 if (newrhs == error_mark_node)
5541 return error_mark_node;
5542 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5546 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
5547 when neither operand has side-effects. */
5548 if (!lvalue_or_else (lhs, lv_assign))
5549 return error_mark_node;
5551 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
5552 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
5554 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
5555 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
5557 TREE_OPERAND (lhs, 0),
5558 TREE_OPERAND (lhs, 1)),
5559 TREE_OPERAND (lhs, 0),
5560 TREE_OPERAND (lhs, 1));
5563 /* Handle (a ? b : c) used as an "lvalue". */
5566 /* Produce (a ? (b = rhs) : (c = rhs))
5567 except that the RHS goes through a save-expr
5568 so the code to compute it is only emitted once. */
5570 tree preeval = NULL_TREE;
5572 rhs = stabilize_expr (rhs, &preeval);
5574 /* Check this here to avoid odd errors when trying to convert
5575 a throw to the type of the COND_EXPR. */
5576 if (!lvalue_or_else (lhs, lv_assign))
5577 return error_mark_node;
5579 cond = build_conditional_expr
5580 (TREE_OPERAND (lhs, 0),
5581 build_modify_expr (TREE_OPERAND (lhs, 1),
5583 build_modify_expr (TREE_OPERAND (lhs, 2),
5586 if (cond == error_mark_node)
5588 /* Make sure the code to compute the rhs comes out
5589 before the split. */
5591 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5599 if (modifycode == INIT_EXPR)
5601 if (TREE_CODE (rhs) == CONSTRUCTOR)
5603 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5604 /* Call convert to generate an error; see PR 11063. */
5605 rhs = convert (lhstype, rhs);
5606 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
5607 TREE_SIDE_EFFECTS (result) = 1;
5610 else if (! IS_AGGR_TYPE (lhstype))
5611 /* Do the default thing. */;
5614 result = build_special_member_call (lhs, complete_ctor_identifier,
5615 build_tree_list (NULL_TREE, rhs),
5616 lhstype, LOOKUP_NORMAL);
5617 if (result == NULL_TREE)
5618 return error_mark_node;
5624 lhs = require_complete_type (lhs);
5625 if (lhs == error_mark_node)
5626 return error_mark_node;
5628 if (modifycode == NOP_EXPR)
5630 /* `operator=' is not an inheritable operator. */
5631 if (! IS_AGGR_TYPE (lhstype))
5632 /* Do the default thing. */;
5635 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5636 lhs, rhs, make_node (NOP_EXPR),
5637 /*overloaded_p=*/NULL);
5638 if (result == NULL_TREE)
5639 return error_mark_node;
5646 /* A binary op has been requested. Combine the old LHS
5647 value with the RHS producing the value we should actually
5648 store into the LHS. */
5650 gcc_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE));
5651 lhs = stabilize_reference (lhs);
5652 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
5653 if (newrhs == error_mark_node)
5655 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
5656 TREE_TYPE (lhs), TREE_TYPE (rhs));
5657 return error_mark_node;
5660 /* Now it looks like a plain assignment. */
5661 modifycode = NOP_EXPR;
5663 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
5664 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
5667 /* The left-hand side must be an lvalue. */
5668 if (!lvalue_or_else (lhs, lv_assign))
5669 return error_mark_node;
5671 /* Warn about modifying something that is `const'. Don't warn if
5672 this is initialization. */
5673 if (modifycode != INIT_EXPR
5674 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5675 /* Functions are not modifiable, even though they are
5677 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5678 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5679 /* If it's an aggregate and any field is const, then it is
5680 effectively const. */
5681 || (CLASS_TYPE_P (lhstype)
5682 && C_TYPE_FIELDS_READONLY (lhstype))))
5683 readonly_error (lhs, "assignment", 0);
5685 /* If storing into a structure or union member, it has probably been
5686 given type `int'. Compute the type that would go with the actual
5687 amount of storage the member occupies. */
5689 if (TREE_CODE (lhs) == COMPONENT_REF
5690 && (TREE_CODE (lhstype) == INTEGER_TYPE
5691 || TREE_CODE (lhstype) == REAL_TYPE
5692 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5694 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5696 /* If storing in a field that is in actuality a short or narrower
5697 than one, we must store in the field in its actual type. */
5699 if (lhstype != TREE_TYPE (lhs))
5701 /* Avoid warnings converting integral types back into enums for
5703 if (TREE_CODE (lhstype) == INTEGER_TYPE
5704 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5706 if (TREE_SIDE_EFFECTS (lhs))
5707 lhs = stabilize_reference (lhs);
5710 lhs = copy_node (lhs);
5711 TREE_TYPE (lhs) = lhstype;
5715 /* Convert new value to destination type. */
5717 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5721 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5722 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5724 error ("incompatible types in assignment of %qT to %qT",
5725 TREE_TYPE (rhs), lhstype);
5726 return error_mark_node;
5729 /* Allow array assignment in compiler-generated code. */
5730 if (! DECL_ARTIFICIAL (current_function_decl))
5732 /* This routine is used for both initialization and assignment.
5733 Make sure the diagnostic message differentiates the context. */
5734 if (modifycode == INIT_EXPR)
5735 error ("array used as initializer");
5737 error ("invalid array assignment");
5738 return error_mark_node;
5741 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5742 ? 1 + (modifycode != INIT_EXPR): 0;
5743 return build_vec_init (lhs, NULL_TREE, newrhs,
5744 /*explicit_default_init_p=*/false,
5748 if (modifycode == INIT_EXPR)
5749 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5750 "initialization", NULL_TREE, 0);
5753 /* Avoid warnings on enum bit fields. */
5754 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5755 && TREE_CODE (lhstype) == INTEGER_TYPE)
5757 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5759 newrhs = convert_force (lhstype, newrhs, 0);
5762 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5764 if (TREE_CODE (newrhs) == CALL_EXPR
5765 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5766 newrhs = build_cplus_new (lhstype, newrhs);
5768 /* Can't initialize directly from a TARGET_EXPR, since that would
5769 cause the lhs to be constructed twice, and possibly result in
5770 accidental self-initialization. So we force the TARGET_EXPR to be
5771 expanded without a target. */
5772 if (TREE_CODE (newrhs) == TARGET_EXPR)
5773 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5774 TREE_OPERAND (newrhs, 0));
5777 if (newrhs == error_mark_node)
5778 return error_mark_node;
5780 if (c_dialect_objc () && flag_objc_gc)
5782 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
5788 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5789 lhstype, lhs, newrhs);
5791 TREE_SIDE_EFFECTS (result) = 1;
5793 TREE_NO_WARNING (result) = 1;
5795 /* If we got the LHS in a different type for storing in,
5796 convert the result back to the nominal type of LHS
5797 so that the value we return always has the same type
5798 as the LHS argument. */
5800 if (olhstype == TREE_TYPE (result))
5804 result = build2 (COMPOUND_EXPR, olhstype, result, olhs);
5805 TREE_NO_WARNING (result) = 1;
5808 return convert_for_assignment (olhstype, result, "assignment",
5813 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5815 if (processing_template_decl)
5816 return build_min_nt (MODOP_EXPR, lhs,
5817 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5819 if (modifycode != NOP_EXPR)
5821 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5822 make_node (modifycode),
5823 /*overloaded_p=*/NULL);
5826 TREE_NO_WARNING (rval) = 1;
5830 return build_modify_expr (lhs, modifycode, rhs);
5834 /* Get difference in deltas for different pointer to member function
5835 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5836 the conversion is invalid, the constant is zero. If
5837 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
5838 If C_CAST_P is true this conversion is taking place as part of a
5841 Note that the naming of FROM and TO is kind of backwards; the return
5842 value is what we add to a TO in order to get a FROM. They are named
5843 this way because we call this function to find out how to convert from
5844 a pointer to member of FROM to a pointer to member of TO. */
5847 get_delta_difference (tree from, tree to,
5848 bool allow_inverse_p,
5855 /* Assume no conversion is required. */
5856 result = integer_zero_node;
5857 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
5858 if (kind == bk_inaccessible || kind == bk_ambig)
5859 error (" in pointer to member function conversion");
5862 if (kind != bk_via_virtual)
5863 result = BINFO_OFFSET (binfo);
5866 tree virt_binfo = binfo_from_vbase (binfo);
5868 /* This is a reinterpret cast, we choose to do nothing. */
5869 if (allow_inverse_p)
5870 warning (0, "pointer to member cast via virtual base %qT",
5871 BINFO_TYPE (virt_binfo));
5873 error ("pointer to member conversion via virtual base %qT",
5874 BINFO_TYPE (virt_binfo));
5877 else if (same_type_ignoring_top_level_qualifiers_p (from, to))
5878 /* Pointer to member of incomplete class is permitted*/;
5879 else if (!allow_inverse_p)
5881 error_not_base_type (from, to);
5882 error (" in pointer to member conversion");
5886 binfo = lookup_base (from, to, c_cast_p ? ba_unique : ba_check, &kind);
5889 if (kind != bk_via_virtual)
5890 result = size_diffop (size_zero_node, BINFO_OFFSET (binfo));
5893 /* This is a reinterpret cast, we choose to do nothing. */
5894 tree virt_binfo = binfo_from_vbase (binfo);
5896 warning (0, "pointer to member cast via virtual base %qT",
5897 BINFO_TYPE (virt_binfo));
5902 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
5906 /* Return a constructor for the pointer-to-member-function TYPE using
5907 the other components as specified. */
5910 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5915 VEC(constructor_elt, gc) *v;
5917 /* Pull the FIELD_DECLs out of the type. */
5918 pfn_field = TYPE_FIELDS (type);
5919 delta_field = TREE_CHAIN (pfn_field);
5921 /* Make sure DELTA has the type we want. */
5922 delta = convert_and_check (delta_type_node, delta);
5924 /* Finish creating the initializer. */
5925 v = VEC_alloc(constructor_elt, gc, 2);
5926 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
5927 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
5928 u = build_constructor (type, v);
5929 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
5930 TREE_INVARIANT (u) = TREE_INVARIANT (pfn) & TREE_INVARIANT (delta);
5931 TREE_STATIC (u) = (TREE_CONSTANT (u)
5932 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5934 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5939 /* Build a constructor for a pointer to member function. It can be
5940 used to initialize global variables, local variable, or used
5941 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5944 If FORCE is nonzero, then force this conversion, even if
5945 we would rather not do it. Usually set when using an explicit
5946 cast. A C-style cast is being processed iff C_CAST_P is true.
5948 Return error_mark_node, if something goes wrong. */
5951 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
5957 if (error_operand_p (pfn))
5958 return error_mark_node;
5960 pfn_type = TREE_TYPE (pfn);
5961 to_type = build_ptrmemfunc_type (type);
5963 /* Handle multiple conversions of pointer to member functions. */
5964 if (TYPE_PTRMEMFUNC_P (pfn_type))
5966 tree delta = NULL_TREE;
5967 tree npfn = NULL_TREE;
5971 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
5972 error ("invalid conversion to type %qT from type %qT",
5975 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5976 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5980 /* We don't have to do any conversion to convert a
5981 pointer-to-member to its own type. But, we don't want to
5982 just return a PTRMEM_CST if there's an explicit cast; that
5983 cast should make the expression an invalid template argument. */
5984 if (TREE_CODE (pfn) != PTRMEM_CST)
5986 if (same_type_p (to_type, pfn_type))
5988 else if (integer_zerop (n))
5989 return build_reinterpret_cast (to_type, pfn);
5992 if (TREE_SIDE_EFFECTS (pfn))
5993 pfn = save_expr (pfn);
5995 /* Obtain the function pointer and the current DELTA. */
5996 if (TREE_CODE (pfn) == PTRMEM_CST)
5997 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
6000 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
6001 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
6004 /* Just adjust the DELTA field. */
6005 gcc_assert (same_type_ignoring_top_level_qualifiers_p
6006 (TREE_TYPE (delta), ptrdiff_type_node));
6007 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
6008 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
6009 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
6010 return build_ptrmemfunc1 (to_type, delta, npfn);
6013 /* Handle null pointer to member function conversions. */
6014 if (integer_zerop (pfn))
6016 pfn = build_c_cast (type, integer_zero_node);
6017 return build_ptrmemfunc1 (to_type,
6022 if (type_unknown_p (pfn))
6023 return instantiate_type (type, pfn, tf_warning_or_error);
6025 fn = TREE_OPERAND (pfn, 0);
6026 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
6027 /* In a template, we will have preserved the
6029 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
6030 return make_ptrmem_cst (to_type, fn);
6033 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
6036 ??? There is no consistency as to the types returned for the above
6037 values. Some code acts as if it were a sizetype and some as if it were
6038 integer_type_node. */
6041 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
6043 tree type = TREE_TYPE (cst);
6044 tree fn = PTRMEM_CST_MEMBER (cst);
6045 tree ptr_class, fn_class;
6047 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6049 /* The class that the function belongs to. */
6050 fn_class = DECL_CONTEXT (fn);
6052 /* The class that we're creating a pointer to member of. */
6053 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
6055 /* First, calculate the adjustment to the function's class. */
6056 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
6059 if (!DECL_VIRTUAL_P (fn))
6060 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
6063 /* If we're dealing with a virtual function, we have to adjust 'this'
6064 again, to point to the base which provides the vtable entry for
6065 fn; the call will do the opposite adjustment. */
6066 tree orig_class = DECL_CONTEXT (fn);
6067 tree binfo = binfo_or_else (orig_class, fn_class);
6068 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6069 *delta, BINFO_OFFSET (binfo));
6070 *delta = fold_if_not_in_template (*delta);
6072 /* We set PFN to the vtable offset at which the function can be
6073 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6074 case delta is shifted left, and then incremented). */
6075 *pfn = DECL_VINDEX (fn);
6076 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
6077 TYPE_SIZE_UNIT (vtable_entry_type));
6078 *pfn = fold_if_not_in_template (*pfn);
6080 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
6082 case ptrmemfunc_vbit_in_pfn:
6083 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6085 *pfn = fold_if_not_in_template (*pfn);
6088 case ptrmemfunc_vbit_in_delta:
6089 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6090 *delta, integer_one_node);
6091 *delta = fold_if_not_in_template (*delta);
6092 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6093 *delta, integer_one_node);
6094 *delta = fold_if_not_in_template (*delta);
6101 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6102 *pfn = fold_if_not_in_template (*pfn);
6106 /* Return an expression for PFN from the pointer-to-member function
6110 pfn_from_ptrmemfunc (tree t)
6112 if (TREE_CODE (t) == PTRMEM_CST)
6117 expand_ptrmemfunc_cst (t, &delta, &pfn);
6122 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6125 /* Convert value RHS to type TYPE as preparation for an assignment to
6126 an lvalue of type TYPE. ERRTYPE is a string to use in error
6127 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6128 are doing the conversion in order to pass the PARMNUMth argument of
6132 convert_for_assignment (tree type, tree rhs,
6133 const char *errtype, tree fndecl, int parmnum)
6136 enum tree_code coder;
6138 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6139 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6140 rhs = TREE_OPERAND (rhs, 0);
6142 rhstype = TREE_TYPE (rhs);
6143 coder = TREE_CODE (rhstype);
6145 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6146 && vector_types_convertible_p (type, rhstype))
6147 return convert (type, rhs);
6149 if (rhs == error_mark_node || rhstype == error_mark_node)
6150 return error_mark_node;
6151 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6152 return error_mark_node;
6154 /* The RHS of an assignment cannot have void type. */
6155 if (coder == VOID_TYPE)
6157 error ("void value not ignored as it ought to be");
6158 return error_mark_node;
6161 /* Simplify the RHS if possible. */
6162 if (TREE_CODE (rhs) == CONST_DECL)
6163 rhs = DECL_INITIAL (rhs);
6165 if (c_dialect_objc ())
6168 tree rname = fndecl;
6170 if (!strcmp (errtype, "assignment"))
6172 else if (!strcmp (errtype, "initialization"))
6176 tree selector = objc_message_selector ();
6180 if (selector && parmno > 1)
6187 if (objc_compare_types (type, rhstype, parmno, rname))
6188 return convert (type, rhs);
6193 The expression is implicitly converted (clause _conv_) to the
6194 cv-unqualified type of the left operand.
6196 We allow bad conversions here because by the time we get to this point
6197 we are committed to doing the conversion. If we end up doing a bad
6198 conversion, convert_like will complain. */
6199 if (!can_convert_arg_bad (type, rhstype, rhs))
6201 /* When -Wno-pmf-conversions is use, we just silently allow
6202 conversions from pointers-to-members to plain pointers. If
6203 the conversion doesn't work, cp_convert will complain. */
6205 && TYPE_PTR_P (type)
6206 && TYPE_PTRMEMFUNC_P (rhstype))
6207 rhs = cp_convert (strip_top_quals (type), rhs);
6210 /* If the right-hand side has unknown type, then it is an
6211 overloaded function. Call instantiate_type to get error
6213 if (rhstype == unknown_type_node)
6214 instantiate_type (type, rhs, tf_warning_or_error);
6216 error ("cannot convert %qT to %qT for argument %qP to %qD",
6217 rhstype, type, parmnum, fndecl);
6219 error ("cannot convert %qT to %qT in %s", rhstype, type, errtype);
6220 return error_mark_node;
6223 if (warn_missing_format_attribute)
6225 const enum tree_code codel = TREE_CODE (type);
6226 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6228 && check_missing_format_attribute (type, rhstype))
6229 warning (OPT_Wmissing_format_attribute,
6230 "%s might be a candidate for a format attribute",
6234 return perform_implicit_conversion (strip_top_quals (type), rhs);
6237 /* Convert RHS to be of type TYPE.
6238 If EXP is nonzero, it is the target of the initialization.
6239 ERRTYPE is a string to use in error messages.
6241 Two major differences between the behavior of
6242 `convert_for_assignment' and `convert_for_initialization'
6243 are that references are bashed in the former, while
6244 copied in the latter, and aggregates are assigned in
6245 the former (operator=) while initialized in the
6248 If using constructor make sure no conversion operator exists, if one does
6249 exist, an ambiguity exists.
6251 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6254 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6255 const char *errtype, tree fndecl, int parmnum)
6257 enum tree_code codel = TREE_CODE (type);
6259 enum tree_code coder;
6261 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6262 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6263 if (TREE_CODE (rhs) == NOP_EXPR
6264 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6265 && codel != REFERENCE_TYPE)
6266 rhs = TREE_OPERAND (rhs, 0);
6268 if (type == error_mark_node
6269 || rhs == error_mark_node
6270 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6271 return error_mark_node;
6273 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6274 && TREE_CODE (type) != ARRAY_TYPE
6275 && (TREE_CODE (type) != REFERENCE_TYPE
6276 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6277 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6278 && (TREE_CODE (type) != REFERENCE_TYPE
6279 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6280 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6281 rhs = decay_conversion (rhs);
6283 rhstype = TREE_TYPE (rhs);
6284 coder = TREE_CODE (rhstype);
6286 if (coder == ERROR_MARK)
6287 return error_mark_node;
6289 /* We accept references to incomplete types, so we can
6290 return here before checking if RHS is of complete type. */
6292 if (codel == REFERENCE_TYPE)
6294 /* This should eventually happen in convert_arguments. */
6295 int savew = 0, savee = 0;
6298 savew = warningcount, savee = errorcount;
6299 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6303 if (warningcount > savew)
6304 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6305 else if (errorcount > savee)
6306 error ("in passing argument %P of %q+D", parmnum, fndecl);
6312 exp = require_complete_type (exp);
6313 if (exp == error_mark_node)
6314 return error_mark_node;
6316 rhstype = non_reference (rhstype);
6318 type = complete_type (type);
6320 if (IS_AGGR_TYPE (type))
6321 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6323 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
6326 /* If RETVAL is the address of, or a reference to, a local variable or
6327 temporary give an appropriate warning. */
6330 maybe_warn_about_returning_address_of_local (tree retval)
6332 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6333 tree whats_returned = retval;
6337 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6338 whats_returned = TREE_OPERAND (whats_returned, 1);
6339 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
6340 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
6341 || TREE_CODE (whats_returned) == NOP_EXPR)
6342 whats_returned = TREE_OPERAND (whats_returned, 0);
6347 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6349 whats_returned = TREE_OPERAND (whats_returned, 0);
6351 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6353 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6354 || TREE_CODE (whats_returned) == TARGET_EXPR)
6356 warning (0, "returning reference to temporary");
6359 if (TREE_CODE (whats_returned) == VAR_DECL
6360 && DECL_NAME (whats_returned)
6361 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6363 warning (0, "reference to non-lvalue returned");
6368 if (DECL_P (whats_returned)
6369 && DECL_NAME (whats_returned)
6370 && DECL_FUNCTION_SCOPE_P (whats_returned)
6371 && !(TREE_STATIC (whats_returned)
6372 || TREE_PUBLIC (whats_returned)))
6374 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6375 warning (0, "reference to local variable %q+D returned",
6378 warning (0, "address of local variable %q+D returned",
6384 /* Check that returning RETVAL from the current function is valid.
6385 Return an expression explicitly showing all conversions required to
6386 change RETVAL into the function return type, and to assign it to
6387 the DECL_RESULT for the function. Set *NO_WARNING to true if
6388 code reaches end of non-void function warning shouldn't be issued
6389 on this RETURN_EXPR. */
6392 check_return_expr (tree retval, bool *no_warning)
6395 /* The type actually returned by the function, after any
6398 int fn_returns_value_p;
6400 *no_warning = false;
6402 /* A `volatile' function is one that isn't supposed to return, ever.
6403 (This is a G++ extension, used to get better code for functions
6404 that call the `volatile' function.) */
6405 if (TREE_THIS_VOLATILE (current_function_decl))
6406 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6408 /* Check for various simple errors. */
6409 if (DECL_DESTRUCTOR_P (current_function_decl))
6412 error ("returning a value from a destructor");
6415 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6417 if (in_function_try_handler)
6418 /* If a return statement appears in a handler of the
6419 function-try-block of a constructor, the program is ill-formed. */
6420 error ("cannot return from a handler of a function-try-block of a constructor");
6422 /* You can't return a value from a constructor. */
6423 error ("returning a value from a constructor");
6427 if (processing_template_decl)
6429 current_function_returns_value = 1;
6433 /* When no explicit return-value is given in a function with a named
6434 return value, the named return value is used. */
6435 result = DECL_RESULT (current_function_decl);
6436 valtype = TREE_TYPE (result);
6437 gcc_assert (valtype != NULL_TREE);
6438 fn_returns_value_p = !VOID_TYPE_P (valtype);
6439 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6442 /* Check for a return statement with no return value in a function
6443 that's supposed to return a value. */
6444 if (!retval && fn_returns_value_p)
6446 pedwarn ("return-statement with no value, in function returning %qT",
6448 /* Clear this, so finish_function won't say that we reach the
6449 end of a non-void function (which we don't, we gave a
6451 current_function_returns_null = 0;
6452 /* And signal caller that TREE_NO_WARNING should be set on the
6453 RETURN_EXPR to avoid control reaches end of non-void function
6454 warnings in tree-cfg.c. */
6457 /* Check for a return statement with a value in a function that
6458 isn't supposed to return a value. */
6459 else if (retval && !fn_returns_value_p)
6461 if (VOID_TYPE_P (TREE_TYPE (retval)))
6462 /* You can return a `void' value from a function of `void'
6463 type. In that case, we have to evaluate the expression for
6464 its side-effects. */
6465 finish_expr_stmt (retval);
6467 pedwarn ("return-statement with a value, in function "
6468 "returning 'void'");
6470 current_function_returns_null = 1;
6472 /* There's really no value to return, after all. */
6476 /* Remember that this function can sometimes return without a
6478 current_function_returns_null = 1;
6480 /* Remember that this function did return a value. */
6481 current_function_returns_value = 1;
6483 /* Check for erroneous operands -- but after giving ourselves a
6484 chance to provide an error about returning a value from a void
6486 if (error_operand_p (retval))
6488 current_function_return_value = error_mark_node;
6489 return error_mark_node;
6492 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
6493 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
6494 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
6495 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
6497 && null_ptr_cst_p (retval))
6498 warning (0, "%<operator new%> must not return NULL unless it is "
6499 "declared %<throw()%> (or -fcheck-new is in effect)");
6501 /* Effective C++ rule 15. See also start_function. */
6503 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
6507 /* The function return type must be a reference to the current
6509 if (TREE_CODE (valtype) == REFERENCE_TYPE
6510 && same_type_ignoring_top_level_qualifiers_p
6511 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
6513 /* Returning '*this' is obviously OK. */
6514 if (retval == current_class_ref)
6516 /* If we are calling a function whose return type is the same of
6517 the current class reference, it is ok. */
6518 else if (TREE_CODE (retval) == INDIRECT_REF
6519 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
6524 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
6527 /* The fabled Named Return Value optimization, as per [class.copy]/15:
6529 [...] For a function with a class return type, if the expression
6530 in the return statement is the name of a local object, and the cv-
6531 unqualified type of the local object is the same as the function
6532 return type, an implementation is permitted to omit creating the tem-
6533 porary object to hold the function return value [...]
6535 So, if this is a value-returning function that always returns the same
6536 local variable, remember it.
6538 It might be nice to be more flexible, and choose the first suitable
6539 variable even if the function sometimes returns something else, but
6540 then we run the risk of clobbering the variable we chose if the other
6541 returned expression uses the chosen variable somehow. And people expect
6542 this restriction, anyway. (jason 2000-11-19)
6544 See finish_function and finalize_nrv for the rest of this optimization. */
6546 if (fn_returns_value_p && flag_elide_constructors)
6548 if (retval != NULL_TREE
6549 && (current_function_return_value == NULL_TREE
6550 || current_function_return_value == retval)
6551 && TREE_CODE (retval) == VAR_DECL
6552 && DECL_CONTEXT (retval) == current_function_decl
6553 && ! TREE_STATIC (retval)
6554 && (DECL_ALIGN (retval)
6555 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6556 && same_type_p ((TYPE_MAIN_VARIANT
6557 (TREE_TYPE (retval))),
6559 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
6560 current_function_return_value = retval;
6562 current_function_return_value = error_mark_node;
6565 /* We don't need to do any conversions when there's nothing being
6570 /* Do any required conversions. */
6571 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6572 /* No conversions are required. */
6576 /* The type the function is declared to return. */
6577 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6579 /* The functype's return type will have been set to void, if it
6580 was an incomplete type. Just treat this as 'return;' */
6581 if (VOID_TYPE_P (functype))
6582 return error_mark_node;
6584 /* First convert the value to the function's return type, then
6585 to the type of return value's location to handle the
6586 case that functype is smaller than the valtype. */
6587 retval = convert_for_initialization
6588 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
6589 "return", NULL_TREE, 0);
6590 retval = convert (valtype, retval);
6592 /* If the conversion failed, treat this just like `return;'. */
6593 if (retval == error_mark_node)
6595 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6596 else if (! current_function_returns_struct
6597 && TREE_CODE (retval) == TARGET_EXPR
6598 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6599 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6600 TREE_OPERAND (retval, 0));
6602 maybe_warn_about_returning_address_of_local (retval);
6605 /* Actually copy the value returned into the appropriate location. */
6606 if (retval && retval != result)
6607 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
6613 /* Returns nonzero if the pointer-type FROM can be converted to the
6614 pointer-type TO via a qualification conversion. If CONSTP is -1,
6615 then we return nonzero if the pointers are similar, and the
6616 cv-qualification signature of FROM is a proper subset of that of TO.
6618 If CONSTP is positive, then all outer pointers have been
6622 comp_ptr_ttypes_real (tree to, tree from, int constp)
6624 bool to_more_cv_qualified = false;
6626 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6628 if (TREE_CODE (to) != TREE_CODE (from))
6631 if (TREE_CODE (from) == OFFSET_TYPE
6632 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
6633 TYPE_OFFSET_BASETYPE (to)))
6636 /* Const and volatile mean something different for function types,
6637 so the usual checks are not appropriate. */
6638 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6640 /* In Objective-C++, some types may have been 'volatilized' by
6641 the compiler for EH; when comparing them here, the volatile
6642 qualification must be ignored. */
6643 bool objc_quals_match = objc_type_quals_match (to, from);
6645 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
6648 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
6652 to_more_cv_qualified = true;
6656 constp &= TYPE_READONLY (to);
6659 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
6660 return ((constp >= 0 || to_more_cv_qualified)
6661 && same_type_ignoring_top_level_qualifiers_p (to, from));
6665 /* When comparing, say, char ** to char const **, this function takes
6666 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6667 types to this function. */
6670 comp_ptr_ttypes (tree to, tree from)
6672 return comp_ptr_ttypes_real (to, from, 1);
6675 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6676 type or inheritance-related types, regardless of cv-quals. */
6679 ptr_reasonably_similar (tree to, tree from)
6681 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6683 /* Any target type is similar enough to void. */
6684 if (TREE_CODE (to) == VOID_TYPE
6685 || TREE_CODE (from) == VOID_TYPE)
6688 if (TREE_CODE (to) != TREE_CODE (from))
6691 if (TREE_CODE (from) == OFFSET_TYPE
6692 && comptypes (TYPE_OFFSET_BASETYPE (to),
6693 TYPE_OFFSET_BASETYPE (from),
6694 COMPARE_BASE | COMPARE_DERIVED))
6697 if (TREE_CODE (to) == VECTOR_TYPE
6698 && vector_types_convertible_p (to, from))
6701 if (TREE_CODE (to) == INTEGER_TYPE
6702 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6705 if (TREE_CODE (to) == FUNCTION_TYPE)
6708 if (TREE_CODE (to) != POINTER_TYPE)
6710 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6711 COMPARE_BASE | COMPARE_DERIVED);
6715 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
6716 pointer-to-member types) are the same, ignoring cv-qualification at
6720 comp_ptr_ttypes_const (tree to, tree from)
6722 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6724 if (TREE_CODE (to) != TREE_CODE (from))
6727 if (TREE_CODE (from) == OFFSET_TYPE
6728 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6729 TYPE_OFFSET_BASETYPE (to)))
6732 if (TREE_CODE (to) != POINTER_TYPE)
6733 return same_type_ignoring_top_level_qualifiers_p (to, from);
6737 /* Returns the type qualifiers for this type, including the qualifiers on the
6738 elements for an array type. */
6741 cp_type_quals (tree type)
6743 type = strip_array_types (type);
6744 if (type == error_mark_node)
6745 return TYPE_UNQUALIFIED;
6746 return TYPE_QUALS (type);
6749 /* Returns nonzero if the TYPE contains a mutable member. */
6752 cp_has_mutable_p (tree type)
6754 type = strip_array_types (type);
6756 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6759 /* Apply the TYPE_QUALS to the new DECL. */
6761 cp_apply_type_quals_to_decl (int type_quals, tree decl)
6763 tree type = TREE_TYPE (decl);
6765 if (type == error_mark_node)
6768 if (TREE_CODE (type) == FUNCTION_TYPE
6769 && type_quals != TYPE_UNQUALIFIED)
6771 /* This was an error in C++98 (cv-qualifiers cannot be added to
6772 a function type), but DR 295 makes the code well-formed by
6773 dropping the extra qualifiers. */
6776 tree bad_type = build_qualified_type (type, type_quals);
6777 pedwarn ("ignoring %qV qualifiers added to function type %qT",
6781 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
6785 /* Avoid setting TREE_READONLY incorrectly. */
6786 if (/* If the object has a constructor, the constructor may modify
6788 TYPE_NEEDS_CONSTRUCTING (type)
6789 /* If the type isn't complete, we don't know yet if it will need
6791 || !COMPLETE_TYPE_P (type)
6792 /* If the type has a mutable component, that component might be
6794 || TYPE_HAS_MUTABLE_P (type))
6795 type_quals &= ~TYPE_QUAL_CONST;
6797 c_apply_type_quals_to_decl (type_quals, decl);
6800 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6801 exemplar types such that casting T1 to T2 is casting away constness
6802 if and only if there is no implicit conversion from T1 to T2. */
6805 casts_away_constness_r (tree *t1, tree *t2)
6810 /* [expr.const.cast]
6812 For multi-level pointer to members and multi-level mixed pointers
6813 and pointers to members (conv.qual), the "member" aspect of a
6814 pointer to member level is ignored when determining if a const
6815 cv-qualifier has been cast away. */
6816 /* [expr.const.cast]
6818 For two pointer types:
6820 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6821 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6824 casting from X1 to X2 casts away constness if, for a non-pointer
6825 type T there does not exist an implicit conversion (clause
6828 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6832 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6833 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
6834 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
6836 *t1 = cp_build_qualified_type (void_type_node,
6837 cp_type_quals (*t1));
6838 *t2 = cp_build_qualified_type (void_type_node,
6839 cp_type_quals (*t2));
6843 quals1 = cp_type_quals (*t1);
6844 quals2 = cp_type_quals (*t2);
6846 if (TYPE_PTRMEM_P (*t1))
6847 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
6849 *t1 = TREE_TYPE (*t1);
6850 if (TYPE_PTRMEM_P (*t2))
6851 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
6853 *t2 = TREE_TYPE (*t2);
6855 casts_away_constness_r (t1, t2);
6856 *t1 = build_pointer_type (*t1);
6857 *t2 = build_pointer_type (*t2);
6858 *t1 = cp_build_qualified_type (*t1, quals1);
6859 *t2 = cp_build_qualified_type (*t2, quals2);
6862 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6866 casts_away_constness (tree t1, tree t2)
6868 if (TREE_CODE (t2) == REFERENCE_TYPE)
6870 /* [expr.const.cast]
6872 Casting from an lvalue of type T1 to an lvalue of type T2
6873 using a reference cast casts away constness if a cast from an
6874 rvalue of type "pointer to T1" to the type "pointer to T2"
6875 casts away constness. */
6876 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6877 return casts_away_constness (build_pointer_type (t1),
6878 build_pointer_type (TREE_TYPE (t2)));
6881 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6882 /* [expr.const.cast]
6884 Casting from an rvalue of type "pointer to data member of X
6885 of type T1" to the type "pointer to data member of Y of type
6886 T2" casts away constness if a cast from an rvalue of type
6887 "pointer to T1" to the type "pointer to T2" casts away
6889 return casts_away_constness
6890 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6891 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6893 /* Casting away constness is only something that makes sense for
6894 pointer or reference types. */
6895 if (TREE_CODE (t1) != POINTER_TYPE
6896 || TREE_CODE (t2) != POINTER_TYPE)
6899 /* Top-level qualifiers don't matter. */
6900 t1 = TYPE_MAIN_VARIANT (t1);
6901 t2 = TYPE_MAIN_VARIANT (t2);
6902 casts_away_constness_r (&t1, &t2);
6903 if (!can_convert (t2, t1))
6909 /* If T is a REFERENCE_TYPE return the type to which T refers.
6910 Otherwise, return T itself. */
6913 non_reference (tree t)
6915 if (TREE_CODE (t) == REFERENCE_TYPE)
6921 /* Return nonzero if REF is an lvalue valid for this language;
6922 otherwise, print an error message and return zero. USE says
6923 how the lvalue is being used and so selects the error message. */
6926 lvalue_or_else (tree ref, enum lvalue_use use)
6928 int win = lvalue_p (ref);