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 while (TYPE_NAME (t) != NULL_TREE)
233 tree x = TYPE_NAME (t);
234 if (TREE_CODE (x) != TYPE_DECL)
236 x = DECL_ORIGINAL_TYPE (x);
244 /* T1 and T2 are arithmetic or enumeration types. Return the type
245 that will result from the "usual arithmetic conversions" on T1 and
246 T2 as described in [expr]. */
249 type_after_usual_arithmetic_conversions (tree t1, tree t2)
251 enum tree_code code1 = TREE_CODE (t1);
252 enum tree_code code2 = TREE_CODE (t2);
255 /* FIXME: Attributes. */
256 gcc_assert (ARITHMETIC_TYPE_P (t1)
257 || TREE_CODE (t1) == COMPLEX_TYPE
258 || TREE_CODE (t1) == VECTOR_TYPE
259 || TREE_CODE (t1) == ENUMERAL_TYPE);
260 gcc_assert (ARITHMETIC_TYPE_P (t2)
261 || TREE_CODE (t2) == COMPLEX_TYPE
262 || TREE_CODE (t1) == VECTOR_TYPE
263 || TREE_CODE (t2) == ENUMERAL_TYPE);
265 /* In what follows, we slightly generalize the rules given in [expr] so
266 as to deal with `long long' and `complex'. First, merge the
268 attributes = (*targetm.merge_type_attributes) (t1, t2);
270 /* If one type is complex, form the common type of the non-complex
271 components, then make that complex. Use T1 or T2 if it is the
273 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
275 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
276 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
278 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
280 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
281 return build_type_attribute_variant (t1, attributes);
282 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
283 return build_type_attribute_variant (t2, attributes);
285 return build_type_attribute_variant (build_complex_type (subtype),
289 if (code1 == VECTOR_TYPE)
291 /* When we get here we should have two vectors of the same size.
292 Just prefer the unsigned one if present. */
293 if (TYPE_UNSIGNED (t1))
294 return build_type_attribute_variant (t1, attributes);
296 return build_type_attribute_variant (t2, attributes);
299 /* If only one is real, use it as the result. */
300 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
301 return build_type_attribute_variant (t1, attributes);
302 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
303 return build_type_attribute_variant (t2, attributes);
305 /* Perform the integral promotions. */
306 if (code1 != REAL_TYPE)
308 t1 = type_promotes_to (t1);
309 t2 = type_promotes_to (t2);
312 /* Both real or both integers; use the one with greater precision. */
313 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
314 return build_type_attribute_variant (t1, attributes);
315 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
316 return build_type_attribute_variant (t2, attributes);
318 /* The types are the same; no need to do anything fancy. */
319 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
320 return build_type_attribute_variant (t1, attributes);
322 if (code1 != REAL_TYPE)
324 /* If one is a sizetype, use it so size_binop doesn't blow up. */
325 if (TYPE_IS_SIZETYPE (t1) > TYPE_IS_SIZETYPE (t2))
326 return build_type_attribute_variant (t1, attributes);
327 if (TYPE_IS_SIZETYPE (t2) > TYPE_IS_SIZETYPE (t1))
328 return build_type_attribute_variant (t2, attributes);
330 /* If one is unsigned long long, then convert the other to unsigned
332 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
333 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
334 return build_type_attribute_variant (long_long_unsigned_type_node,
336 /* If one is a long long, and the other is an unsigned long, and
337 long long can represent all the values of an unsigned long, then
338 convert to a long long. Otherwise, convert to an unsigned long
339 long. Otherwise, if either operand is long long, convert the
342 Since we're here, we know the TYPE_PRECISION is the same;
343 therefore converting to long long cannot represent all the values
344 of an unsigned long, so we choose unsigned long long in that
346 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
347 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
349 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
350 ? long_long_unsigned_type_node
351 : long_long_integer_type_node);
352 return build_type_attribute_variant (t, attributes);
355 /* Go through the same procedure, but for longs. */
356 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
357 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
358 return build_type_attribute_variant (long_unsigned_type_node,
360 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
361 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
363 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
364 ? long_unsigned_type_node : long_integer_type_node);
365 return build_type_attribute_variant (t, attributes);
367 /* Otherwise prefer the unsigned one. */
368 if (TYPE_UNSIGNED (t1))
369 return build_type_attribute_variant (t1, attributes);
371 return build_type_attribute_variant (t2, attributes);
375 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
376 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
377 return build_type_attribute_variant (long_double_type_node,
379 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
380 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
381 return build_type_attribute_variant (double_type_node,
383 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
384 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
385 return build_type_attribute_variant (float_type_node,
388 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
389 the standard C++ floating-point types. Logic earlier in this
390 function has already eliminated the possibility that
391 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
392 compelling reason to choose one or the other. */
393 return build_type_attribute_variant (t1, attributes);
397 /* Subroutine of composite_pointer_type to implement the recursive
398 case. See that function for documentation fo the parameters. */
401 composite_pointer_type_r (tree t1, tree t2, const char* location)
408 /* Determine the types pointed to by T1 and T2. */
409 if (TREE_CODE (t1) == POINTER_TYPE)
411 pointee1 = TREE_TYPE (t1);
412 pointee2 = TREE_TYPE (t2);
416 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
417 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
422 Otherwise, the composite pointer type is a pointer type
423 similar (_conv.qual_) to the type of one of the operands,
424 with a cv-qualification signature (_conv.qual_) that is the
425 union of the cv-qualification signatures of the operand
427 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
428 result_type = pointee1;
429 else if ((TREE_CODE (pointee1) == POINTER_TYPE
430 && TREE_CODE (pointee2) == POINTER_TYPE)
431 || (TYPE_PTR_TO_MEMBER_P (pointee1)
432 && TYPE_PTR_TO_MEMBER_P (pointee2)))
433 result_type = composite_pointer_type_r (pointee1, pointee2, location);
436 pedwarn ("%s between distinct pointer types %qT and %qT "
439 result_type = void_type_node;
441 result_type = cp_build_qualified_type (result_type,
442 (cp_type_quals (pointee1)
443 | cp_type_quals (pointee2)));
444 /* If the original types were pointers to members, so is the
446 if (TYPE_PTR_TO_MEMBER_P (t1))
448 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
449 TYPE_PTRMEM_CLASS_TYPE (t2)))
450 pedwarn ("%s between distinct pointer types %qT and %qT "
453 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
457 result_type = build_pointer_type (result_type);
459 /* Merge the attributes. */
460 attributes = (*targetm.merge_type_attributes) (t1, t2);
461 return build_type_attribute_variant (result_type, attributes);
464 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
465 ARG1 and ARG2 are the values with those types. The LOCATION is a
466 string describing the current location, in case an error occurs.
468 This routine also implements the computation of a common type for
469 pointers-to-members as per [expr.eq]. */
472 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
473 const char* location)
480 If one operand is a null pointer constant, the composite pointer
481 type is the type of the other operand. */
482 if (null_ptr_cst_p (arg1))
484 if (null_ptr_cst_p (arg2))
491 If one of the operands has type "pointer to cv1 void*", then
492 the other has type "pointer to cv2T", and the composite pointer
493 type is "pointer to cv12 void", where cv12 is the union of cv1
496 If either type is a pointer to void, make sure it is T1. */
497 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
505 /* Now, if T1 is a pointer to void, merge the qualifiers. */
506 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
511 if (pedantic && TYPE_PTRFN_P (t2))
512 pedwarn ("ISO C++ forbids %s between pointer of type %<void *%> "
513 "and pointer-to-function", location);
515 = cp_build_qualified_type (void_type_node,
516 (cp_type_quals (TREE_TYPE (t1))
517 | cp_type_quals (TREE_TYPE (t2))));
518 result_type = build_pointer_type (result_type);
519 /* Merge the attributes. */
520 attributes = (*targetm.merge_type_attributes) (t1, t2);
521 return build_type_attribute_variant (result_type, attributes);
524 if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE
525 && TREE_CODE (t2) == POINTER_TYPE)
527 if (objc_compare_types (t1, t2, -3, NULL_TREE))
531 /* [expr.eq] permits the application of a pointer conversion to
532 bring the pointers to a common type. */
533 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
534 && CLASS_TYPE_P (TREE_TYPE (t1))
535 && CLASS_TYPE_P (TREE_TYPE (t2))
536 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
539 class1 = TREE_TYPE (t1);
540 class2 = TREE_TYPE (t2);
542 if (DERIVED_FROM_P (class1, class2))
543 t2 = (build_pointer_type
544 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
545 else if (DERIVED_FROM_P (class2, class1))
546 t1 = (build_pointer_type
547 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
550 error ("%s between distinct pointer types %qT and %qT "
551 "lacks a cast", location, t1, t2);
552 return error_mark_node;
555 /* [expr.eq] permits the application of a pointer-to-member
556 conversion to change the class type of one of the types. */
557 else if (TYPE_PTR_TO_MEMBER_P (t1)
558 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
559 TYPE_PTRMEM_CLASS_TYPE (t2)))
561 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
562 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
564 if (DERIVED_FROM_P (class1, class2))
565 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
566 else if (DERIVED_FROM_P (class2, class1))
567 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
570 error ("%s between distinct pointer-to-member types %qT and %qT "
571 "lacks a cast", location, t1, t2);
572 return error_mark_node;
576 return composite_pointer_type_r (t1, t2, location);
579 /* Return the merged type of two types.
580 We assume that comptypes has already been done and returned 1;
581 if that isn't so, this may crash.
583 This just combines attributes and default arguments; any other
584 differences would cause the two types to compare unalike. */
587 merge_types (tree t1, tree t2)
589 enum tree_code code1;
590 enum tree_code code2;
593 /* Save time if the two types are the same. */
596 if (original_type (t1) == original_type (t2))
599 /* If one type is nonsense, use the other. */
600 if (t1 == error_mark_node)
602 if (t2 == error_mark_node)
605 /* Merge the attributes. */
606 attributes = (*targetm.merge_type_attributes) (t1, t2);
608 if (TYPE_PTRMEMFUNC_P (t1))
609 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
610 if (TYPE_PTRMEMFUNC_P (t2))
611 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
613 code1 = TREE_CODE (t1);
614 code2 = TREE_CODE (t2);
620 /* For two pointers, do this recursively on the target type. */
622 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
623 int quals = cp_type_quals (t1);
625 if (code1 == POINTER_TYPE)
626 t1 = build_pointer_type (target);
628 t1 = build_reference_type (target);
629 t1 = build_type_attribute_variant (t1, attributes);
630 t1 = cp_build_qualified_type (t1, quals);
632 if (TREE_CODE (target) == METHOD_TYPE)
633 t1 = build_ptrmemfunc_type (t1);
642 quals = cp_type_quals (t1);
643 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
644 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
645 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
647 t1 = cp_build_qualified_type (t1, quals);
653 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
654 /* Save space: see if the result is identical to one of the args. */
655 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
656 return build_type_attribute_variant (t1, attributes);
657 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
658 return build_type_attribute_variant (t2, attributes);
659 /* Merge the element types, and have a size if either arg has one. */
660 t1 = build_cplus_array_type
661 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
666 /* Function types: prefer the one that specified arg types.
667 If both do, merge the arg types. Also merge the return types. */
669 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
670 tree p1 = TYPE_ARG_TYPES (t1);
671 tree p2 = TYPE_ARG_TYPES (t2);
674 /* Save space: see if the result is identical to one of the args. */
675 if (valtype == TREE_TYPE (t1) && ! p2)
676 return cp_build_type_attribute_variant (t1, attributes);
677 if (valtype == TREE_TYPE (t2) && ! p1)
678 return cp_build_type_attribute_variant (t2, attributes);
680 /* Simple way if one arg fails to specify argument types. */
681 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
683 rval = build_function_type (valtype, p2);
684 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
685 rval = build_exception_variant (rval, raises);
686 return cp_build_type_attribute_variant (rval, attributes);
688 raises = TYPE_RAISES_EXCEPTIONS (t1);
689 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
691 rval = build_function_type (valtype, p1);
693 rval = build_exception_variant (rval, raises);
694 return cp_build_type_attribute_variant (rval, attributes);
697 rval = build_function_type (valtype, commonparms (p1, p2));
698 t1 = build_exception_variant (rval, raises);
704 /* Get this value the long way, since TYPE_METHOD_BASETYPE
705 is just the main variant of this. */
706 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
707 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
710 /* If this was a member function type, get back to the
711 original type of type member function (i.e., without
712 the class instance variable up front. */
713 t1 = build_function_type (TREE_TYPE (t1),
714 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
715 t2 = build_function_type (TREE_TYPE (t2),
716 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
717 t3 = merge_types (t1, t2);
718 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
719 TYPE_ARG_TYPES (t3));
720 t1 = build_exception_variant (t3, raises);
725 /* There is no need to merge attributes into a TYPENAME_TYPE.
726 When the type is instantiated it will have whatever
727 attributes result from the instantiation. */
732 return cp_build_type_attribute_variant (t1, attributes);
735 /* Return the common type of two types.
736 We assume that comptypes has already been done and returned 1;
737 if that isn't so, this may crash.
739 This is the type for the result of most arithmetic operations
740 if the operands have the given two types. */
743 common_type (tree t1, tree t2)
745 enum tree_code code1;
746 enum tree_code code2;
748 /* If one type is nonsense, bail. */
749 if (t1 == error_mark_node || t2 == error_mark_node)
750 return error_mark_node;
752 code1 = TREE_CODE (t1);
753 code2 = TREE_CODE (t2);
755 if ((ARITHMETIC_TYPE_P (t1) || code1 == ENUMERAL_TYPE
756 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
757 && (ARITHMETIC_TYPE_P (t2) || code2 == ENUMERAL_TYPE
758 || code2 == COMPLEX_TYPE || code2 == VECTOR_TYPE))
759 return type_after_usual_arithmetic_conversions (t1, t2);
761 else if ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
762 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
763 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)))
764 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
770 /* Compare two exception specifier types for exactness or subsetness, if
771 allowed. Returns false for mismatch, true for match (same, or
774 [except.spec] "If a class X ... objects of class X or any class publicly
775 and unambiguously derived from X. Similarly, if a pointer type Y * ...
776 exceptions of type Y * or that are pointers to any type publicly and
777 unambiguously derived from Y. Otherwise a function only allows exceptions
778 that have the same type ..."
779 This does not mention cv qualifiers and is different to what throw
780 [except.throw] and catch [except.catch] will do. They will ignore the
781 top level cv qualifiers, and allow qualifiers in the pointer to class
784 We implement the letter of the standard. */
787 comp_except_types (tree a, tree b, bool exact)
789 if (same_type_p (a, b))
793 if (cp_type_quals (a) || cp_type_quals (b))
796 if (TREE_CODE (a) == POINTER_TYPE
797 && TREE_CODE (b) == POINTER_TYPE)
801 if (cp_type_quals (a) || cp_type_quals (b))
805 if (TREE_CODE (a) != RECORD_TYPE
806 || TREE_CODE (b) != RECORD_TYPE)
809 if (PUBLICLY_UNIQUELY_DERIVED_P (a, b))
815 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
816 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
817 otherwise it must be exact. Exception lists are unordered, but
818 we've already filtered out duplicates. Most lists will be in order,
819 we should try to make use of that. */
822 comp_except_specs (tree t1, tree t2, bool exact)
831 if (t1 == NULL_TREE) /* T1 is ... */
832 return t2 == NULL_TREE || !exact;
833 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
834 return t2 != NULL_TREE && !TREE_VALUE (t2);
835 if (t2 == NULL_TREE) /* T2 is ... */
837 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
840 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
841 Count how many we find, to determine exactness. For exact matching and
842 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
844 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
846 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
848 tree a = TREE_VALUE (probe);
849 tree b = TREE_VALUE (t2);
851 if (comp_except_types (a, b, exact))
853 if (probe == base && exact)
854 base = TREE_CHAIN (probe);
859 if (probe == NULL_TREE)
862 return !exact || base == NULL_TREE || length == list_length (t1);
865 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
866 [] can match [size]. */
869 comp_array_types (tree t1, tree t2, bool allow_redeclaration)
878 /* The type of the array elements must be the same. */
879 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
882 d1 = TYPE_DOMAIN (t1);
883 d2 = TYPE_DOMAIN (t2);
888 /* If one of the arrays is dimensionless, and the other has a
889 dimension, they are of different types. However, it is valid to
897 declarations for an array object can specify
898 array types that differ by the presence or absence of a major
899 array bound (_dcl.array_). */
901 return allow_redeclaration;
903 /* Check that the dimensions are the same. */
905 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
907 max1 = TYPE_MAX_VALUE (d1);
908 max2 = TYPE_MAX_VALUE (d2);
909 if (processing_template_decl && !abi_version_at_least (2)
910 && !value_dependent_expression_p (max1)
911 && !value_dependent_expression_p (max2))
913 /* With abi-1 we do not fold non-dependent array bounds, (and
914 consequently mangle them incorrectly). We must therefore
915 fold them here, to verify the domains have the same
921 if (!cp_tree_equal (max1, max2))
927 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
928 is a bitwise-or of the COMPARE_* flags. */
931 comptypes (tree t1, tree t2, int strict)
936 /* Suppress errors caused by previously reported errors. */
937 if (t1 == error_mark_node || t2 == error_mark_node)
940 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
942 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
943 current instantiation. */
944 if (TREE_CODE (t1) == TYPENAME_TYPE)
946 tree resolved = resolve_typename_type (t1, /*only_current_p=*/true);
948 if (resolved != error_mark_node)
952 if (TREE_CODE (t2) == TYPENAME_TYPE)
954 tree resolved = resolve_typename_type (t2, /*only_current_p=*/true);
956 if (resolved != error_mark_node)
960 /* If either type is the internal version of sizetype, use the
962 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
963 && TYPE_ORIG_SIZE_TYPE (t1))
964 t1 = TYPE_ORIG_SIZE_TYPE (t1);
966 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
967 && TYPE_ORIG_SIZE_TYPE (t2))
968 t2 = TYPE_ORIG_SIZE_TYPE (t2);
970 if (TYPE_PTRMEMFUNC_P (t1))
971 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
972 if (TYPE_PTRMEMFUNC_P (t2))
973 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
975 /* Different classes of types can't be compatible. */
976 if (TREE_CODE (t1) != TREE_CODE (t2))
979 /* Qualifiers must match. For array types, we will check when we
980 recur on the array element types. */
981 if (TREE_CODE (t1) != ARRAY_TYPE
982 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
984 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
987 /* Allow for two different type nodes which have essentially the same
988 definition. Note that we already checked for equality of the type
989 qualifiers (just above). */
991 if (TREE_CODE (t1) != ARRAY_TYPE
992 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
995 /* Compare the types. Break out if they could be the same. */
996 switch (TREE_CODE (t1))
998 case TEMPLATE_TEMPLATE_PARM:
999 case BOUND_TEMPLATE_TEMPLATE_PARM:
1000 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1001 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
1003 if (!comp_template_parms
1004 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1005 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1007 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1009 /* Don't check inheritance. */
1010 strict = COMPARE_STRICT;
1015 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1016 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1017 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1018 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1021 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1023 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1029 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1030 strict & ~COMPARE_REDECLARATION))
1032 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1037 case REFERENCE_TYPE:
1038 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1039 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)
1040 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1046 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1048 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1053 /* Target types must match incl. qualifiers. */
1054 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1058 case TEMPLATE_TYPE_PARM:
1059 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1060 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
1065 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1066 TYPENAME_TYPE_FULLNAME (t2)))
1068 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1072 case UNBOUND_CLASS_TEMPLATE:
1073 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1075 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1080 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1085 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1086 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1094 /* If we get here, we know that from a target independent POV the
1095 types are the same. Make sure the target attributes are also
1097 return targetm.comp_type_attributes (t1, t2);
1100 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1103 at_least_as_qualified_p (tree type1, tree type2)
1105 int q1 = cp_type_quals (type1);
1106 int q2 = cp_type_quals (type2);
1108 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1109 return (q1 & q2) == q2;
1112 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1113 more cv-qualified that TYPE1, and 0 otherwise. */
1116 comp_cv_qualification (tree type1, tree type2)
1118 int q1 = cp_type_quals (type1);
1119 int q2 = cp_type_quals (type2);
1124 if ((q1 & q2) == q2)
1126 else if ((q1 & q2) == q1)
1132 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1133 subset of the cv-qualification signature of TYPE2, and the types
1134 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1137 comp_cv_qual_signature (tree type1, tree type2)
1139 if (comp_ptr_ttypes_real (type2, type1, -1))
1141 else if (comp_ptr_ttypes_real (type1, type2, -1))
1147 /* If two types share a common base type, return that basetype.
1148 If there is not a unique most-derived base type, this function
1149 returns ERROR_MARK_NODE. */
1152 common_base_type (tree tt1, tree tt2)
1154 tree best = NULL_TREE;
1157 /* If one is a baseclass of another, that's good enough. */
1158 if (UNIQUELY_DERIVED_FROM_P (tt1, tt2))
1160 if (UNIQUELY_DERIVED_FROM_P (tt2, tt1))
1163 /* Otherwise, try to find a unique baseclass of TT1
1164 that is shared by TT2, and follow that down. */
1165 for (i = BINFO_N_BASE_BINFOS (TYPE_BINFO (tt1))-1; i >= 0; i--)
1167 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (tt1), i));
1168 tree trial = common_base_type (basetype, tt2);
1172 if (trial == error_mark_node)
1174 if (best == NULL_TREE)
1176 else if (best != trial)
1177 return error_mark_node;
1182 for (i = BINFO_N_BASE_BINFOS (TYPE_BINFO (tt2))-1; i >= 0; i--)
1184 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (tt2), i));
1185 tree trial = common_base_type (tt1, basetype);
1189 if (trial == error_mark_node)
1191 if (best == NULL_TREE)
1193 else if (best != trial)
1194 return error_mark_node;
1200 /* Subroutines of `comptypes'. */
1202 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1203 equivalent in the sense that functions with those parameter types
1204 can have equivalent types. The two lists must be equivalent,
1205 element by element. */
1208 compparms (tree parms1, tree parms2)
1212 /* An unspecified parmlist matches any specified parmlist
1213 whose argument types don't need default promotions. */
1215 for (t1 = parms1, t2 = parms2;
1217 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1219 /* If one parmlist is shorter than the other,
1220 they fail to match. */
1223 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1230 /* Process a sizeof or alignof expression where the operand is a
1234 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1236 enum tree_code type_code;
1238 const char *op_name;
1240 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1241 if (type == error_mark_node)
1242 return error_mark_node;
1244 if (dependent_type_p (type))
1246 value = build_min (op, size_type_node, type);
1247 TREE_READONLY (value) = 1;
1251 op_name = operator_name_info[(int) op].name;
1253 type = non_reference (type);
1254 type_code = TREE_CODE (type);
1256 if (type_code == METHOD_TYPE)
1258 if (complain && (pedantic || warn_pointer_arith))
1259 pedwarn ("invalid application of %qs to a member function", op_name);
1260 value = size_one_node;
1263 value = c_sizeof_or_alignof_type (complete_type (type),
1270 /* Process a sizeof expression where the operand is an expression. */
1273 cxx_sizeof_expr (tree e)
1275 if (e == error_mark_node)
1276 return error_mark_node;
1278 if (processing_template_decl)
1280 e = build_min (SIZEOF_EXPR, size_type_node, e);
1281 TREE_SIDE_EFFECTS (e) = 0;
1282 TREE_READONLY (e) = 1;
1287 if (TREE_CODE (e) == COMPONENT_REF
1288 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1289 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1291 error ("invalid application of %<sizeof%> to a bit-field");
1294 else if (is_overloaded_fn (e))
1296 pedwarn ("ISO C++ forbids applying %<sizeof%> to an expression of "
1300 else if (type_unknown_p (e))
1302 cxx_incomplete_type_error (e, TREE_TYPE (e));
1308 return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, true);
1311 /* Implement the __alignof keyword: Return the minimum required
1312 alignment of E, measured in bytes. For VAR_DECL's and
1313 FIELD_DECL's return DECL_ALIGN (which can be set from an
1314 "aligned" __attribute__ specification). */
1317 cxx_alignof_expr (tree e)
1321 if (e == error_mark_node)
1322 return error_mark_node;
1324 if (processing_template_decl)
1326 e = build_min (ALIGNOF_EXPR, size_type_node, e);
1327 TREE_SIDE_EFFECTS (e) = 0;
1328 TREE_READONLY (e) = 1;
1333 if (TREE_CODE (e) == VAR_DECL)
1334 t = size_int (DECL_ALIGN_UNIT (e));
1335 else if (TREE_CODE (e) == COMPONENT_REF
1336 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1337 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1339 error ("invalid application of %<__alignof%> to a bit-field");
1342 else if (TREE_CODE (e) == COMPONENT_REF
1343 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL)
1344 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1)));
1345 else if (is_overloaded_fn (e))
1347 pedwarn ("ISO C++ forbids applying %<__alignof%> to an expression of "
1351 else if (type_unknown_p (e))
1353 cxx_incomplete_type_error (e, TREE_TYPE (e));
1357 return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR, true);
1359 return fold_convert (size_type_node, t);
1362 /* Process a sizeof or alignof expression E with code OP where the operand
1363 is an expression. */
1366 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op)
1368 if (op == SIZEOF_EXPR)
1369 return cxx_sizeof_expr (e);
1371 return cxx_alignof_expr (e);
1374 /* EXPR is being used in a context that is not a function call.
1379 The expression can be used only as the left-hand operand of a
1380 member function call.
1382 [expr.mptr.operator]
1384 If the result of .* or ->* is a function, then that result can be
1385 used only as the operand for the function call operator ().
1387 by issuing an error message if appropriate. Returns true iff EXPR
1388 violates these rules. */
1391 invalid_nonstatic_memfn_p (tree expr)
1393 if (TREE_CODE (TREE_TYPE (expr)) == METHOD_TYPE)
1395 error ("invalid use of non-static member function");
1401 /* Perform the conversions in [expr] that apply when an lvalue appears
1402 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1403 function-to-pointer conversions.
1405 In addition manifest constants are replaced by their values. */
1408 decay_conversion (tree exp)
1411 enum tree_code code;
1413 type = TREE_TYPE (exp);
1414 code = TREE_CODE (type);
1416 if (type == error_mark_node)
1417 return error_mark_node;
1419 if (type_unknown_p (exp))
1421 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1422 return error_mark_node;
1425 exp = decl_constant_value (exp);
1427 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1428 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1430 if (code == VOID_TYPE)
1432 error ("void value not ignored as it ought to be");
1433 return error_mark_node;
1435 if (invalid_nonstatic_memfn_p (exp))
1436 return error_mark_node;
1437 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1438 return build_unary_op (ADDR_EXPR, exp, 0);
1439 if (code == ARRAY_TYPE)
1444 if (TREE_CODE (exp) == INDIRECT_REF)
1445 return build_nop (build_pointer_type (TREE_TYPE (type)),
1446 TREE_OPERAND (exp, 0));
1448 if (TREE_CODE (exp) == COMPOUND_EXPR)
1450 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1451 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1452 TREE_OPERAND (exp, 0), op1);
1456 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1458 error ("invalid use of non-lvalue array");
1459 return error_mark_node;
1462 ptrtype = build_pointer_type (TREE_TYPE (type));
1464 if (TREE_CODE (exp) == VAR_DECL)
1466 if (!cxx_mark_addressable (exp))
1467 return error_mark_node;
1468 adr = build_nop (ptrtype, build_address (exp));
1471 /* This way is better for a COMPONENT_REF since it can
1472 simplify the offset for a component. */
1473 adr = build_unary_op (ADDR_EXPR, exp, 1);
1474 return cp_convert (ptrtype, adr);
1477 /* [basic.lval]: Class rvalues can have cv-qualified types; non-class
1478 rvalues always have cv-unqualified types. */
1479 if (! CLASS_TYPE_P (type))
1480 exp = cp_convert (TYPE_MAIN_VARIANT (type), exp);
1486 default_conversion (tree exp)
1488 exp = decay_conversion (exp);
1490 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1491 exp = perform_integral_promotions (exp);
1496 /* EXPR is an expression with an integral or enumeration type.
1497 Perform the integral promotions in [conv.prom], and return the
1501 perform_integral_promotions (tree expr)
1506 type = TREE_TYPE (expr);
1507 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1508 promoted_type = type_promotes_to (type);
1509 if (type != promoted_type)
1510 expr = cp_convert (promoted_type, expr);
1514 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1518 inline_conversion (tree exp)
1520 if (TREE_CODE (exp) == FUNCTION_DECL)
1521 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1526 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1527 decay_conversion to one. */
1530 string_conv_p (tree totype, tree exp, int warn)
1534 if (TREE_CODE (totype) != POINTER_TYPE)
1537 t = TREE_TYPE (totype);
1538 if (!same_type_p (t, char_type_node)
1539 && !same_type_p (t, wchar_type_node))
1542 if (TREE_CODE (exp) == STRING_CST)
1544 /* Make sure that we don't try to convert between char and wchar_t. */
1545 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1550 /* Is this a string constant which has decayed to 'const char *'? */
1551 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1552 if (!same_type_p (TREE_TYPE (exp), t))
1555 if (TREE_CODE (exp) != ADDR_EXPR
1556 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1560 /* This warning is not very useful, as it complains about printf. */
1562 warning (OPT_Wwrite_strings, "deprecated conversion from string constant to %qT'", totype);
1567 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1568 can, for example, use as an lvalue. This code used to be in
1569 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1570 expressions, where we're dealing with aggregates. But now it's again only
1571 called from unary_complex_lvalue. The case (in particular) that led to
1572 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1576 rationalize_conditional_expr (enum tree_code code, tree t)
1578 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1579 the first operand is always the one to be used if both operands
1580 are equal, so we know what conditional expression this used to be. */
1581 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1583 /* The following code is incorrect if either operand side-effects. */
1584 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0))
1585 && !TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)));
1587 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1588 ? LE_EXPR : GE_EXPR),
1589 TREE_OPERAND (t, 0),
1590 TREE_OPERAND (t, 1),
1591 /*overloaded_p=*/NULL),
1592 build_unary_op (code, TREE_OPERAND (t, 0), 0),
1593 build_unary_op (code, TREE_OPERAND (t, 1), 0));
1597 build_conditional_expr (TREE_OPERAND (t, 0),
1598 build_unary_op (code, TREE_OPERAND (t, 1), 0),
1599 build_unary_op (code, TREE_OPERAND (t, 2), 0));
1602 /* Given the TYPE of an anonymous union field inside T, return the
1603 FIELD_DECL for the field. If not found return NULL_TREE. Because
1604 anonymous unions can nest, we must also search all anonymous unions
1605 that are directly reachable. */
1608 lookup_anon_field (tree t, tree type)
1612 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1614 if (TREE_STATIC (field))
1616 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1619 /* If we find it directly, return the field. */
1620 if (DECL_NAME (field) == NULL_TREE
1621 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1626 /* Otherwise, it could be nested, search harder. */
1627 if (DECL_NAME (field) == NULL_TREE
1628 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1630 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1638 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1639 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1640 non-NULL, it indicates the path to the base used to name MEMBER.
1641 If PRESERVE_REFERENCE is true, the expression returned will have
1642 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1643 returned will have the type referred to by the reference.
1645 This function does not perform access control; that is either done
1646 earlier by the parser when the name of MEMBER is resolved to MEMBER
1647 itself, or later when overload resolution selects one of the
1648 functions indicated by MEMBER. */
1651 build_class_member_access_expr (tree object, tree member,
1652 tree access_path, bool preserve_reference)
1656 tree result = NULL_TREE;
1658 if (object == error_mark_node || member == error_mark_node)
1659 return error_mark_node;
1661 gcc_assert (DECL_P (member) || BASELINK_P (member));
1665 The type of the first expression shall be "class object" (of a
1667 object_type = TREE_TYPE (object);
1668 if (!currently_open_class (object_type)
1669 && !complete_type_or_else (object_type, object))
1670 return error_mark_node;
1671 if (!CLASS_TYPE_P (object_type))
1673 error ("request for member %qD in %qE, which is of non-class type %qT",
1674 member, object, object_type);
1675 return error_mark_node;
1678 /* The standard does not seem to actually say that MEMBER must be a
1679 member of OBJECT_TYPE. However, that is clearly what is
1681 if (DECL_P (member))
1683 member_scope = DECL_CLASS_CONTEXT (member);
1685 if (TREE_DEPRECATED (member))
1686 warn_deprecated_use (member);
1689 member_scope = BINFO_TYPE (BASELINK_BINFO (member));
1690 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1691 presently be the anonymous union. Go outwards until we find a
1692 type related to OBJECT_TYPE. */
1693 while (ANON_AGGR_TYPE_P (member_scope)
1694 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1696 member_scope = TYPE_CONTEXT (member_scope);
1697 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1699 if (TREE_CODE (member) == FIELD_DECL)
1700 error ("invalid use of nonstatic data member %qE", member);
1702 error ("%qD is not a member of %qT", member, object_type);
1703 return error_mark_node;
1706 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1707 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1708 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1710 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1712 object = build_indirect_ref (temp, NULL);
1715 /* In [expr.ref], there is an explicit list of the valid choices for
1716 MEMBER. We check for each of those cases here. */
1717 if (TREE_CODE (member) == VAR_DECL)
1719 /* A static data member. */
1721 /* If OBJECT has side-effects, they are supposed to occur. */
1722 if (TREE_SIDE_EFFECTS (object))
1723 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1725 else if (TREE_CODE (member) == FIELD_DECL)
1727 /* A non-static data member. */
1732 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1733 && integer_zerop (TREE_OPERAND (object, 0)));
1735 /* Convert OBJECT to the type of MEMBER. */
1736 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1737 TYPE_MAIN_VARIANT (member_scope)))
1742 binfo = lookup_base (access_path ? access_path : object_type,
1743 member_scope, ba_unique, &kind);
1744 if (binfo == error_mark_node)
1745 return error_mark_node;
1747 /* It is invalid to try to get to a virtual base of a
1748 NULL object. The most common cause is invalid use of
1750 if (null_object_p && kind == bk_via_virtual)
1752 error ("invalid access to non-static data member %qD of "
1755 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
1756 return error_mark_node;
1759 /* Convert to the base. */
1760 object = build_base_path (PLUS_EXPR, object, binfo,
1762 /* If we found the base successfully then we should be able
1763 to convert to it successfully. */
1764 gcc_assert (object != error_mark_node);
1767 /* Complain about other invalid uses of offsetof, even though they will
1768 give the right answer. Note that we complain whether or not they
1769 actually used the offsetof macro, since there's no way to know at this
1770 point. So we just give a warning, instead of a pedwarn. */
1771 /* Do not produce this warning for base class field references, because
1772 we know for a fact that didn't come from offsetof. This does occur
1773 in various testsuite cases where a null object is passed where a
1774 vtable access is required. */
1775 if (null_object_p && warn_invalid_offsetof
1776 && CLASSTYPE_NON_POD_P (object_type)
1777 && !DECL_FIELD_IS_BASE (member)
1778 && !skip_evaluation)
1780 warning (0, "invalid access to non-static data member %qD of NULL object",
1782 warning (0, "(perhaps the %<offsetof%> macro was used incorrectly)");
1785 /* If MEMBER is from an anonymous aggregate, we have converted
1786 OBJECT so that it refers to the class containing the
1787 anonymous union. Generate a reference to the anonymous union
1788 itself, and recur to find MEMBER. */
1789 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
1790 /* When this code is called from build_field_call, the
1791 object already has the type of the anonymous union.
1792 That is because the COMPONENT_REF was already
1793 constructed, and was then disassembled before calling
1794 build_field_call. After the function-call code is
1795 cleaned up, this waste can be eliminated. */
1796 && (!same_type_ignoring_top_level_qualifiers_p
1797 (TREE_TYPE (object), DECL_CONTEXT (member))))
1799 tree anonymous_union;
1801 anonymous_union = lookup_anon_field (TREE_TYPE (object),
1802 DECL_CONTEXT (member));
1803 object = build_class_member_access_expr (object,
1805 /*access_path=*/NULL_TREE,
1806 preserve_reference);
1809 /* Compute the type of the field, as described in [expr.ref]. */
1810 type_quals = TYPE_UNQUALIFIED;
1811 member_type = TREE_TYPE (member);
1812 if (TREE_CODE (member_type) != REFERENCE_TYPE)
1814 type_quals = (cp_type_quals (member_type)
1815 | cp_type_quals (object_type));
1817 /* A field is const (volatile) if the enclosing object, or the
1818 field itself, is const (volatile). But, a mutable field is
1819 not const, even within a const object. */
1820 if (DECL_MUTABLE_P (member))
1821 type_quals &= ~TYPE_QUAL_CONST;
1822 member_type = cp_build_qualified_type (member_type, type_quals);
1825 result = build3 (COMPONENT_REF, member_type, object, member,
1827 result = fold_if_not_in_template (result);
1829 /* Mark the expression const or volatile, as appropriate. Even
1830 though we've dealt with the type above, we still have to mark the
1831 expression itself. */
1832 if (type_quals & TYPE_QUAL_CONST)
1833 TREE_READONLY (result) = 1;
1834 if (type_quals & TYPE_QUAL_VOLATILE)
1835 TREE_THIS_VOLATILE (result) = 1;
1837 else if (BASELINK_P (member))
1839 /* The member is a (possibly overloaded) member function. */
1843 /* If the MEMBER is exactly one static member function, then we
1844 know the type of the expression. Otherwise, we must wait
1845 until overload resolution has been performed. */
1846 functions = BASELINK_FUNCTIONS (member);
1847 if (TREE_CODE (functions) == FUNCTION_DECL
1848 && DECL_STATIC_FUNCTION_P (functions))
1849 type = TREE_TYPE (functions);
1851 type = unknown_type_node;
1852 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1853 base. That will happen when the function is called. */
1854 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
1856 else if (TREE_CODE (member) == CONST_DECL)
1858 /* The member is an enumerator. */
1860 /* If OBJECT has side-effects, they are supposed to occur. */
1861 if (TREE_SIDE_EFFECTS (object))
1862 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
1867 error ("invalid use of %qD", member);
1868 return error_mark_node;
1871 if (!preserve_reference)
1874 If E2 is declared to have type "reference to T", then ... the
1875 type of E1.E2 is T. */
1876 result = convert_from_reference (result);
1881 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1882 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1885 lookup_destructor (tree object, tree scope, tree dtor_name)
1887 tree object_type = TREE_TYPE (object);
1888 tree dtor_type = TREE_OPERAND (dtor_name, 0);
1891 if (scope && !check_dtor_name (scope, dtor_type))
1893 error ("qualified type %qT does not match destructor name ~%qT",
1895 return error_mark_node;
1897 if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
1899 error ("the type being destroyed is %qT, but the destructor refers to %qT",
1900 TYPE_MAIN_VARIANT (object_type), dtor_type);
1901 return error_mark_node;
1903 expr = lookup_member (dtor_type, complete_dtor_identifier,
1904 /*protect=*/1, /*want_type=*/false);
1905 expr = (adjust_result_of_qualified_name_lookup
1906 (expr, dtor_type, object_type));
1910 /* An expression of the form "A::template B" has been resolved to
1911 DECL. Issue a diagnostic if B is not a template or template
1915 check_template_keyword (tree decl)
1917 /* The standard says:
1921 If a name prefixed by the keyword template is not a member
1922 template, the program is ill-formed.
1924 DR 228 removed the restriction that the template be a member
1927 DR 96, if accepted would add the further restriction that explicit
1928 template arguments must be provided if the template keyword is
1929 used, but, as of 2005-10-16, that DR is still in "drafting". If
1930 this DR is accepted, then the semantic checks here can be
1931 simplified, as the entity named must in fact be a template
1932 specialization, rather than, as at present, a set of overloaded
1933 functions containing at least one template function. */
1934 if (TREE_CODE (decl) != TEMPLATE_DECL
1935 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
1937 if (!is_overloaded_fn (decl))
1938 pedwarn ("%qD is not a template", decl);
1943 if (BASELINK_P (fns))
1944 fns = BASELINK_FUNCTIONS (fns);
1947 tree fn = OVL_CURRENT (fns);
1948 if (TREE_CODE (fn) == TEMPLATE_DECL
1949 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
1951 if (TREE_CODE (fn) == FUNCTION_DECL
1952 && DECL_USE_TEMPLATE (fn)
1953 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
1955 fns = OVL_NEXT (fns);
1958 pedwarn ("%qD is not a template", decl);
1963 /* This function is called by the parser to process a class member
1964 access expression of the form OBJECT.NAME. NAME is a node used by
1965 the parser to represent a name; it is not yet a DECL. It may,
1966 however, be a BASELINK where the BASELINK_FUNCTIONS is a
1967 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
1968 there is no reason to do the lookup twice, so the parser keeps the
1969 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
1970 be a template via the use of the "A::template B" syntax. */
1973 finish_class_member_access_expr (tree object, tree name, bool template_p)
1978 tree access_path = NULL_TREE;
1979 tree orig_object = object;
1980 tree orig_name = name;
1982 if (object == error_mark_node || name == error_mark_node)
1983 return error_mark_node;
1985 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
1986 if (!objc_is_public (object, name))
1987 return error_mark_node;
1989 object_type = TREE_TYPE (object);
1991 if (processing_template_decl)
1993 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
1994 dependent_type_p (object_type)
1995 /* If NAME is just an IDENTIFIER_NODE, then the expression
1997 || TREE_CODE (object) == IDENTIFIER_NODE
1998 /* If NAME is "f<args>", where either 'f' or 'args' is
1999 dependent, then the expression is dependent. */
2000 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2001 && dependent_template_id_p (TREE_OPERAND (name, 0),
2002 TREE_OPERAND (name, 1)))
2003 /* If NAME is "T::X" where "T" is dependent, then the
2004 expression is dependent. */
2005 || (TREE_CODE (name) == SCOPE_REF
2006 && TYPE_P (TREE_OPERAND (name, 0))
2007 && dependent_type_p (TREE_OPERAND (name, 0))))
2008 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2009 object = build_non_dependent_expr (object);
2014 The type of the first expression shall be "class object" (of a
2016 if (!currently_open_class (object_type)
2017 && !complete_type_or_else (object_type, object))
2018 return error_mark_node;
2019 if (!CLASS_TYPE_P (object_type))
2021 error ("request for member %qD in %qE, which is of non-class type %qT",
2022 name, object, object_type);
2023 return error_mark_node;
2026 if (BASELINK_P (name))
2027 /* A member function that has already been looked up. */
2031 bool is_template_id = false;
2032 tree template_args = NULL_TREE;
2035 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2037 is_template_id = true;
2038 template_args = TREE_OPERAND (name, 1);
2039 name = TREE_OPERAND (name, 0);
2041 if (TREE_CODE (name) == OVERLOAD)
2042 name = DECL_NAME (get_first_fn (name));
2043 else if (DECL_P (name))
2044 name = DECL_NAME (name);
2047 if (TREE_CODE (name) == SCOPE_REF)
2049 /* A qualified name. The qualifying class or namespace `S'
2050 has already been looked up; it is either a TYPE or a
2052 scope = TREE_OPERAND (name, 0);
2053 name = TREE_OPERAND (name, 1);
2055 /* If SCOPE is a namespace, then the qualified name does not
2056 name a member of OBJECT_TYPE. */
2057 if (TREE_CODE (scope) == NAMESPACE_DECL)
2059 error ("%<%D::%D%> is not a member of %qT",
2060 scope, name, object_type);
2061 return error_mark_node;
2064 gcc_assert (CLASS_TYPE_P (scope));
2065 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2066 || TREE_CODE (name) == BIT_NOT_EXPR);
2068 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2069 access_path = lookup_base (object_type, scope, ba_check, NULL);
2070 if (access_path == error_mark_node)
2071 return error_mark_node;
2074 error ("%qT is not a base of %qT", scope, object_type);
2075 return error_mark_node;
2081 access_path = object_type;
2084 if (TREE_CODE (name) == BIT_NOT_EXPR)
2085 member = lookup_destructor (object, scope, name);
2088 /* Look up the member. */
2089 member = lookup_member (access_path, name, /*protect=*/1,
2090 /*want_type=*/false);
2091 if (member == NULL_TREE)
2093 error ("%qD has no member named %qE", object_type, name);
2094 return error_mark_node;
2096 if (member == error_mark_node)
2097 return error_mark_node;
2102 tree template = member;
2104 if (BASELINK_P (template))
2105 template = lookup_template_function (template, template_args);
2108 error ("%qD is not a member template function", name);
2109 return error_mark_node;
2114 if (TREE_DEPRECATED (member))
2115 warn_deprecated_use (member);
2118 check_template_keyword (member);
2120 expr = build_class_member_access_expr (object, member, access_path,
2121 /*preserve_reference=*/false);
2122 if (processing_template_decl && expr != error_mark_node)
2124 if (BASELINK_P (member))
2126 if (TREE_CODE (orig_name) == SCOPE_REF)
2127 BASELINK_QUALIFIED_P (member) = 1;
2130 return build_min_non_dep (COMPONENT_REF, expr,
2131 orig_object, orig_name,
2138 /* Return an expression for the MEMBER_NAME field in the internal
2139 representation of PTRMEM, a pointer-to-member function. (Each
2140 pointer-to-member function type gets its own RECORD_TYPE so it is
2141 more convenient to access the fields by name than by FIELD_DECL.)
2142 This routine converts the NAME to a FIELD_DECL and then creates the
2143 node for the complete expression. */
2146 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2152 /* This code is a stripped down version of
2153 build_class_member_access_expr. It does not work to use that
2154 routine directly because it expects the object to be of class
2156 ptrmem_type = TREE_TYPE (ptrmem);
2157 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2158 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2159 /*want_type=*/false);
2160 member_type = cp_build_qualified_type (TREE_TYPE (member),
2161 cp_type_quals (ptrmem_type));
2162 return fold_build3 (COMPONENT_REF, member_type,
2163 ptrmem, member, NULL_TREE);
2166 /* Given an expression PTR for a pointer, return an expression
2167 for the value pointed to.
2168 ERRORSTRING is the name of the operator to appear in error messages.
2170 This function may need to overload OPERATOR_FNNAME.
2171 Must also handle REFERENCE_TYPEs for C++. */
2174 build_x_indirect_ref (tree expr, const char *errorstring)
2176 tree orig_expr = expr;
2179 if (processing_template_decl)
2181 if (type_dependent_expression_p (expr))
2182 return build_min_nt (INDIRECT_REF, expr);
2183 expr = build_non_dependent_expr (expr);
2186 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2187 NULL_TREE, /*overloaded_p=*/NULL);
2189 rval = build_indirect_ref (expr, errorstring);
2191 if (processing_template_decl && rval != error_mark_node)
2192 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2198 build_indirect_ref (tree ptr, const char *errorstring)
2202 if (ptr == error_mark_node)
2203 return error_mark_node;
2205 if (ptr == current_class_ptr)
2206 return current_class_ref;
2208 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2209 ? ptr : decay_conversion (ptr));
2210 type = TREE_TYPE (pointer);
2212 if (POINTER_TYPE_P (type))
2216 If the type of the expression is "pointer to T," the type
2217 of the result is "T."
2219 We must use the canonical variant because certain parts of
2220 the back end, like fold, do pointer comparisons between
2222 tree t = canonical_type_variant (TREE_TYPE (type));
2224 if (VOID_TYPE_P (t))
2226 /* A pointer to incomplete type (other than cv void) can be
2227 dereferenced [expr.unary.op]/1 */
2228 error ("%qT is not a pointer-to-object type", type);
2229 return error_mark_node;
2231 else if (TREE_CODE (pointer) == ADDR_EXPR
2232 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2233 /* The POINTER was something like `&x'. We simplify `*&x' to
2235 return TREE_OPERAND (pointer, 0);
2238 tree ref = build1 (INDIRECT_REF, t, pointer);
2240 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2241 so that we get the proper error message if the result is used
2242 to assign to. Also, &* is supposed to be a no-op. */
2243 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2244 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2245 TREE_SIDE_EFFECTS (ref)
2246 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2250 /* `pointer' won't be an error_mark_node if we were given a
2251 pointer to member, so it's cool to check for this here. */
2252 else if (TYPE_PTR_TO_MEMBER_P (type))
2253 error ("invalid use of %qs on pointer to member", errorstring);
2254 else if (pointer != error_mark_node)
2257 error ("invalid type argument of %qs", errorstring);
2259 error ("invalid type argument");
2261 return error_mark_node;
2264 /* This handles expressions of the form "a[i]", which denotes
2267 This is logically equivalent in C to *(a+i), but we may do it differently.
2268 If A is a variable or a member, we generate a primitive ARRAY_REF.
2269 This avoids forcing the array out of registers, and can work on
2270 arrays that are not lvalues (for example, members of structures returned
2273 If INDEX is of some user-defined type, it must be converted to
2274 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2275 will inherit the type of the array, which will be some pointer type. */
2278 build_array_ref (tree array, tree idx)
2282 error ("subscript missing in array reference");
2283 return error_mark_node;
2286 if (TREE_TYPE (array) == error_mark_node
2287 || TREE_TYPE (idx) == error_mark_node)
2288 return error_mark_node;
2290 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2292 switch (TREE_CODE (array))
2296 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2297 return build2 (COMPOUND_EXPR, TREE_TYPE (value),
2298 TREE_OPERAND (array, 0), value);
2302 return build_conditional_expr
2303 (TREE_OPERAND (array, 0),
2304 build_array_ref (TREE_OPERAND (array, 1), idx),
2305 build_array_ref (TREE_OPERAND (array, 2), idx));
2311 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2315 warn_array_subscript_with_type_char (idx);
2317 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2319 error ("array subscript is not an integer");
2320 return error_mark_node;
2323 /* Apply integral promotions *after* noticing character types.
2324 (It is unclear why we do these promotions -- the standard
2325 does not say that we should. In fact, the natural thing would
2326 seem to be to convert IDX to ptrdiff_t; we're performing
2327 pointer arithmetic.) */
2328 idx = perform_integral_promotions (idx);
2330 /* An array that is indexed by a non-constant
2331 cannot be stored in a register; we must be able to do
2332 address arithmetic on its address.
2333 Likewise an array of elements of variable size. */
2334 if (TREE_CODE (idx) != INTEGER_CST
2335 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2336 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2339 if (!cxx_mark_addressable (array))
2340 return error_mark_node;
2343 /* An array that is indexed by a constant value which is not within
2344 the array bounds cannot be stored in a register either; because we
2345 would get a crash in store_bit_field/extract_bit_field when trying
2346 to access a non-existent part of the register. */
2347 if (TREE_CODE (idx) == INTEGER_CST
2348 && TYPE_DOMAIN (TREE_TYPE (array))
2349 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2351 if (!cxx_mark_addressable (array))
2352 return error_mark_node;
2355 if (pedantic && !lvalue_p (array))
2356 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2358 /* Note in C++ it is valid to subscript a `register' array, since
2359 it is valid to take the address of something with that
2360 storage specification. */
2364 while (TREE_CODE (foo) == COMPONENT_REF)
2365 foo = TREE_OPERAND (foo, 0);
2366 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2367 warning (OPT_Wextra, "subscripting array declared %<register%>");
2370 type = TREE_TYPE (TREE_TYPE (array));
2371 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2372 /* Array ref is const/volatile if the array elements are
2373 or if the array is.. */
2374 TREE_READONLY (rval)
2375 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2376 TREE_SIDE_EFFECTS (rval)
2377 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2378 TREE_THIS_VOLATILE (rval)
2379 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2380 return require_complete_type (fold_if_not_in_template (rval));
2384 tree ar = default_conversion (array);
2385 tree ind = default_conversion (idx);
2387 /* Put the integer in IND to simplify error checking. */
2388 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2395 if (ar == error_mark_node)
2398 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2400 error ("subscripted value is neither array nor pointer");
2401 return error_mark_node;
2403 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2405 error ("array subscript is not an integer");
2406 return error_mark_node;
2409 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2414 /* Resolve a pointer to member function. INSTANCE is the object
2415 instance to use, if the member points to a virtual member.
2417 This used to avoid checking for virtual functions if basetype
2418 has no virtual functions, according to an earlier ANSI draft.
2419 With the final ISO C++ rules, such an optimization is
2420 incorrect: A pointer to a derived member can be static_cast
2421 to pointer-to-base-member, as long as the dynamic object
2422 later has the right member. */
2425 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2427 if (TREE_CODE (function) == OFFSET_REF)
2428 function = TREE_OPERAND (function, 1);
2430 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2432 tree idx, delta, e1, e2, e3, vtbl, basetype;
2433 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2435 tree instance_ptr = *instance_ptrptr;
2436 tree instance_save_expr = 0;
2437 if (instance_ptr == error_mark_node)
2439 if (TREE_CODE (function) == PTRMEM_CST)
2441 /* Extracting the function address from a pmf is only
2442 allowed with -Wno-pmf-conversions. It only works for
2444 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2445 e1 = convert (fntype, e1);
2450 error ("object missing in use of %qE", function);
2451 return error_mark_node;
2455 if (TREE_SIDE_EFFECTS (instance_ptr))
2456 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2458 if (TREE_SIDE_EFFECTS (function))
2459 function = save_expr (function);
2461 /* Start by extracting all the information from the PMF itself. */
2462 e3 = pfn_from_ptrmemfunc (function);
2463 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2464 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2465 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2467 case ptrmemfunc_vbit_in_pfn:
2468 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2469 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2472 case ptrmemfunc_vbit_in_delta:
2473 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2474 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2481 /* Convert down to the right base before using the instance. A
2482 special case is that in a pointer to member of class C, C may
2483 be incomplete. In that case, the function will of course be
2484 a member of C, and no conversion is required. In fact,
2485 lookup_base will fail in that case, because incomplete
2486 classes do not have BINFOs. */
2487 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2488 if (!same_type_ignoring_top_level_qualifiers_p
2489 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2491 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2492 basetype, ba_check, NULL);
2493 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2495 if (instance_ptr == error_mark_node)
2496 return error_mark_node;
2498 /* ...and then the delta in the PMF. */
2499 instance_ptr = build2 (PLUS_EXPR, TREE_TYPE (instance_ptr),
2500 instance_ptr, delta);
2502 /* Hand back the adjusted 'this' argument to our caller. */
2503 *instance_ptrptr = instance_ptr;
2505 /* Next extract the vtable pointer from the object. */
2506 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2508 vtbl = build_indirect_ref (vtbl, NULL);
2510 /* Finally, extract the function pointer from the vtable. */
2511 e2 = fold_build2 (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx);
2512 e2 = build_indirect_ref (e2, NULL);
2513 TREE_CONSTANT (e2) = 1;
2514 TREE_INVARIANT (e2) = 1;
2516 /* When using function descriptors, the address of the
2517 vtable entry is treated as a function pointer. */
2518 if (TARGET_VTABLE_USES_DESCRIPTORS)
2519 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2520 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2522 TREE_TYPE (e2) = TREE_TYPE (e3);
2523 e1 = build_conditional_expr (e1, e2, e3);
2525 /* Make sure this doesn't get evaluated first inside one of the
2526 branches of the COND_EXPR. */
2527 if (instance_save_expr)
2528 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2529 instance_save_expr, e1);
2537 build_function_call (tree function, tree params)
2539 tree fntype, fndecl;
2540 tree coerced_params;
2541 tree name = NULL_TREE;
2543 tree original = function;
2545 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2546 expressions, like those used for ObjC messenger dispatches. */
2547 function = objc_rewrite_function_call (function, params);
2549 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2550 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2551 if (TREE_CODE (function) == NOP_EXPR
2552 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2553 function = TREE_OPERAND (function, 0);
2555 if (TREE_CODE (function) == FUNCTION_DECL)
2557 name = DECL_NAME (function);
2559 mark_used (function);
2562 /* Convert anything with function type to a pointer-to-function. */
2563 if (pedantic && DECL_MAIN_P (function))
2564 pedwarn ("ISO C++ forbids calling %<::main%> from within program");
2566 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2567 (because calling an inline function does not mean the function
2568 needs to be separately compiled). */
2570 if (DECL_INLINE (function))
2571 function = inline_conversion (function);
2573 function = build_addr_func (function);
2579 function = build_addr_func (function);
2582 if (function == error_mark_node)
2583 return error_mark_node;
2585 fntype = TREE_TYPE (function);
2587 if (TYPE_PTRMEMFUNC_P (fntype))
2589 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2590 "function in %<%E (...)%>",
2592 return error_mark_node;
2595 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2596 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2598 if (!((TREE_CODE (fntype) == POINTER_TYPE
2599 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2601 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2603 error ("%qE cannot be used as a function", original);
2604 return error_mark_node;
2607 /* fntype now gets the type of function pointed to. */
2608 fntype = TREE_TYPE (fntype);
2610 /* Convert the parameters to the types declared in the
2611 function prototype, or apply default promotions. */
2613 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2614 params, fndecl, LOOKUP_NORMAL);
2615 if (coerced_params == error_mark_node)
2616 return error_mark_node;
2618 /* Check for errors in format strings and inappropriately
2621 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params,
2622 TYPE_ARG_TYPES (fntype));
2624 return build_cxx_call (function, coerced_params);
2627 /* Convert the actual parameter expressions in the list VALUES
2628 to the types in the list TYPELIST.
2629 If parmdecls is exhausted, or when an element has NULL as its type,
2630 perform the default conversions.
2632 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2634 This is also where warnings about wrong number of args are generated.
2636 Return a list of expressions for the parameters as converted.
2638 Both VALUES and the returned value are chains of TREE_LIST nodes
2639 with the elements of the list in the TREE_VALUE slots of those nodes.
2641 In C++, unspecified trailing parameters can be filled in with their
2642 default arguments, if such were specified. Do so here. */
2645 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2647 tree typetail, valtail;
2648 tree result = NULL_TREE;
2649 const char *called_thing = 0;
2652 /* Argument passing is always copy-initialization. */
2653 flags |= LOOKUP_ONLYCONVERTING;
2657 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2659 if (DECL_NAME (fndecl) == NULL_TREE
2660 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2661 called_thing = "constructor";
2663 called_thing = "member function";
2666 called_thing = "function";
2669 for (valtail = values, typetail = typelist;
2671 valtail = TREE_CHAIN (valtail), i++)
2673 tree type = typetail ? TREE_VALUE (typetail) : 0;
2674 tree val = TREE_VALUE (valtail);
2676 if (val == error_mark_node)
2677 return error_mark_node;
2679 if (type == void_type_node)
2683 error ("too many arguments to %s %q+#D", called_thing, fndecl);
2684 error ("at this point in file");
2687 error ("too many arguments to function");
2688 /* In case anybody wants to know if this argument
2691 TREE_TYPE (tree_last (result)) = error_mark_node;
2695 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2696 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2697 if (TREE_CODE (val) == NOP_EXPR
2698 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2699 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2700 val = TREE_OPERAND (val, 0);
2702 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2704 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2705 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2706 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2707 val = decay_conversion (val);
2710 if (val == error_mark_node)
2711 return error_mark_node;
2715 /* Formal parm type is specified by a function prototype. */
2718 if (!COMPLETE_TYPE_P (complete_type (type)))
2721 error ("parameter %P of %qD has incomplete type %qT",
2724 error ("parameter %P has incomplete type %qT", i, type);
2725 parmval = error_mark_node;
2729 parmval = convert_for_initialization
2730 (NULL_TREE, type, val, flags,
2731 "argument passing", fndecl, i);
2732 parmval = convert_for_arg_passing (type, parmval);
2735 if (parmval == error_mark_node)
2736 return error_mark_node;
2738 result = tree_cons (NULL_TREE, parmval, result);
2742 if (fndecl && DECL_BUILT_IN (fndecl)
2743 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2744 /* Don't do ellipsis conversion for __built_in_constant_p
2745 as this will result in spurious warnings for non-POD
2747 val = require_complete_type (val);
2749 val = convert_arg_to_ellipsis (val);
2751 result = tree_cons (NULL_TREE, val, result);
2755 typetail = TREE_CHAIN (typetail);
2758 if (typetail != 0 && typetail != void_list_node)
2760 /* See if there are default arguments that can be used. */
2761 if (TREE_PURPOSE (typetail)
2762 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2764 for (; typetail != void_list_node; ++i)
2767 = convert_default_arg (TREE_VALUE (typetail),
2768 TREE_PURPOSE (typetail),
2771 if (parmval == error_mark_node)
2772 return error_mark_node;
2774 result = tree_cons (0, parmval, result);
2775 typetail = TREE_CHAIN (typetail);
2776 /* ends with `...'. */
2777 if (typetail == NULL_TREE)
2785 error ("too few arguments to %s %q+#D", called_thing, fndecl);
2786 error ("at this point in file");
2789 error ("too few arguments to function");
2790 return error_mark_list;
2794 return nreverse (result);
2797 /* Build a binary-operation expression, after performing default
2798 conversions on the operands. CODE is the kind of expression to build. */
2801 build_x_binary_op (enum tree_code code, tree arg1, tree arg2,
2811 if (processing_template_decl)
2813 if (type_dependent_expression_p (arg1)
2814 || type_dependent_expression_p (arg2))
2815 return build_min_nt (code, arg1, arg2);
2816 arg1 = build_non_dependent_expr (arg1);
2817 arg2 = build_non_dependent_expr (arg2);
2820 if (code == DOTSTAR_EXPR)
2821 expr = build_m_component_ref (arg1, arg2);
2823 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
2826 if (processing_template_decl && expr != error_mark_node)
2827 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
2832 /* Build a binary-operation expression without default conversions.
2833 CODE is the kind of expression to build.
2834 This function differs from `build' in several ways:
2835 the data type of the result is computed and recorded in it,
2836 warnings are generated if arg data types are invalid,
2837 special handling for addition and subtraction of pointers is known,
2838 and some optimization is done (operations on narrow ints
2839 are done in the narrower type when that gives the same result).
2840 Constant folding is also done before the result is returned.
2842 Note that the operands will never have enumeral types
2843 because either they have just had the default conversions performed
2844 or they have both just been converted to some other type in which
2845 the arithmetic is to be done.
2847 C++: must do special pointer arithmetic when implementing
2848 multiple inheritance, and deal with pointer to member functions. */
2851 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2852 int convert_p ATTRIBUTE_UNUSED)
2855 enum tree_code code0, code1;
2857 const char *invalid_op_diag;
2859 /* Expression code to give to the expression when it is built.
2860 Normally this is CODE, which is what the caller asked for,
2861 but in some special cases we change it. */
2862 enum tree_code resultcode = code;
2864 /* Data type in which the computation is to be performed.
2865 In the simplest cases this is the common type of the arguments. */
2866 tree result_type = NULL;
2868 /* Nonzero means operands have already been type-converted
2869 in whatever way is necessary.
2870 Zero means they need to be converted to RESULT_TYPE. */
2873 /* Nonzero means create the expression with this type, rather than
2875 tree build_type = 0;
2877 /* Nonzero means after finally constructing the expression
2878 convert it to this type. */
2879 tree final_type = 0;
2883 /* Nonzero if this is an operation like MIN or MAX which can
2884 safely be computed in short if both args are promoted shorts.
2885 Also implies COMMON.
2886 -1 indicates a bitwise operation; this makes a difference
2887 in the exact conditions for when it is safe to do the operation
2888 in a narrower mode. */
2891 /* Nonzero if this is a comparison operation;
2892 if both args are promoted shorts, compare the original shorts.
2893 Also implies COMMON. */
2894 int short_compare = 0;
2896 /* Nonzero if this is a right-shift operation, which can be computed on the
2897 original short and then promoted if the operand is a promoted short. */
2898 int short_shift = 0;
2900 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2903 /* True if both operands have arithmetic type. */
2904 bool arithmetic_types_p;
2906 /* Apply default conversions. */
2910 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2911 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2912 || code == TRUTH_XOR_EXPR)
2914 if (!really_overloaded_fn (op0))
2915 op0 = decay_conversion (op0);
2916 if (!really_overloaded_fn (op1))
2917 op1 = decay_conversion (op1);
2921 if (!really_overloaded_fn (op0))
2922 op0 = default_conversion (op0);
2923 if (!really_overloaded_fn (op1))
2924 op1 = default_conversion (op1);
2927 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2928 STRIP_TYPE_NOPS (op0);
2929 STRIP_TYPE_NOPS (op1);
2931 /* DTRT if one side is an overloaded function, but complain about it. */
2932 if (type_unknown_p (op0))
2934 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
2935 if (t != error_mark_node)
2937 pedwarn ("assuming cast to type %qT from overloaded function",
2942 if (type_unknown_p (op1))
2944 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
2945 if (t != error_mark_node)
2947 pedwarn ("assuming cast to type %qT from overloaded function",
2953 type0 = TREE_TYPE (op0);
2954 type1 = TREE_TYPE (op1);
2956 /* The expression codes of the data types of the arguments tell us
2957 whether the arguments are integers, floating, pointers, etc. */
2958 code0 = TREE_CODE (type0);
2959 code1 = TREE_CODE (type1);
2961 /* If an error was already reported for one of the arguments,
2962 avoid reporting another error. */
2964 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
2965 return error_mark_node;
2967 if ((invalid_op_diag
2968 = targetm.invalid_binary_op (code, type0, type1)))
2970 error (invalid_op_diag);
2971 return error_mark_node;
2977 /* Handle the pointer + int case. */
2978 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2979 return cp_pointer_int_sum (PLUS_EXPR, op0, op1);
2980 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
2981 return cp_pointer_int_sum (PLUS_EXPR, op1, op0);
2987 /* Subtraction of two similar pointers.
2988 We must subtract them as integers, then divide by object size. */
2989 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
2990 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
2992 return pointer_diff (op0, op1, common_type (type0, type1));
2993 /* Handle pointer minus int. Just like pointer plus int. */
2994 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2995 return cp_pointer_int_sum (MINUS_EXPR, op0, op1);
3004 case TRUNC_DIV_EXPR:
3006 case FLOOR_DIV_EXPR:
3007 case ROUND_DIV_EXPR:
3008 case EXACT_DIV_EXPR:
3009 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3010 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3011 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3012 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3014 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
3015 warning (OPT_Wdiv_by_zero, "division by zero in %<%E / 0%>", op0);
3016 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
3017 warning (OPT_Wdiv_by_zero, "division by zero in %<%E / 0.%>", op0);
3019 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3020 code0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3021 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
3022 code1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3024 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
3025 resultcode = RDIV_EXPR;
3027 /* When dividing two signed integers, we have to promote to int.
3028 unless we divide by a constant != -1. Note that default
3029 conversion will have been performed on the operands at this
3030 point, so we have to dig out the original type to find out if
3032 shorten = ((TREE_CODE (op0) == NOP_EXPR
3033 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3034 || (TREE_CODE (op1) == INTEGER_CST
3035 && ! integer_all_onesp (op1)));
3044 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3045 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE))
3049 case TRUNC_MOD_EXPR:
3050 case FLOOR_MOD_EXPR:
3051 if (code1 == INTEGER_TYPE && integer_zerop (op1))
3052 warning (OPT_Wdiv_by_zero, "division by zero in %<%E %% 0%>", op0);
3053 else if (code1 == REAL_TYPE && real_zerop (op1))
3054 warning (OPT_Wdiv_by_zero, "division by zero in %<%E %% 0.%>", op0);
3056 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3058 /* Although it would be tempting to shorten always here, that loses
3059 on some targets, since the modulo instruction is undefined if the
3060 quotient can't be represented in the computation mode. We shorten
3061 only if unsigned or if dividing by something we know != -1. */
3062 shorten = ((TREE_CODE (op0) == NOP_EXPR
3063 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3064 || (TREE_CODE (op1) == INTEGER_CST
3065 && ! integer_all_onesp (op1)));
3070 case TRUTH_ANDIF_EXPR:
3071 case TRUTH_ORIF_EXPR:
3072 case TRUTH_AND_EXPR:
3074 result_type = boolean_type_node;
3077 /* Shift operations: result has same type as first operand;
3078 always convert second operand to int.
3079 Also set SHORT_SHIFT if shifting rightward. */
3082 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3084 result_type = type0;
3085 if (TREE_CODE (op1) == INTEGER_CST)
3087 if (tree_int_cst_lt (op1, integer_zero_node))
3088 warning (0, "right shift count is negative");
3091 if (! integer_zerop (op1))
3093 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3094 warning (0, "right shift count >= width of type");
3097 /* Convert the shift-count to an integer, regardless of
3098 size of value being shifted. */
3099 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3100 op1 = cp_convert (integer_type_node, op1);
3101 /* Avoid converting op1 to result_type later. */
3107 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3109 result_type = type0;
3110 if (TREE_CODE (op1) == INTEGER_CST)
3112 if (tree_int_cst_lt (op1, integer_zero_node))
3113 warning (0, "left shift count is negative");
3114 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3115 warning (0, "left shift count >= width of type");
3117 /* Convert the shift-count to an integer, regardless of
3118 size of value being shifted. */
3119 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3120 op1 = cp_convert (integer_type_node, op1);
3121 /* Avoid converting op1 to result_type later. */
3128 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3130 result_type = type0;
3131 if (TREE_CODE (op1) == INTEGER_CST)
3133 if (tree_int_cst_lt (op1, integer_zero_node))
3134 warning (0, "%s rotate count is negative",
3135 (code == LROTATE_EXPR) ? "left" : "right");
3136 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3137 warning (0, "%s rotate count >= width of type",
3138 (code == LROTATE_EXPR) ? "left" : "right");
3140 /* Convert the shift-count to an integer, regardless of
3141 size of value being shifted. */
3142 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3143 op1 = cp_convert (integer_type_node, op1);
3149 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
3150 warning (OPT_Wfloat_equal,
3151 "comparing floating point with == or != is unsafe");
3152 if ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3153 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0)))
3154 warning (OPT_Wstring_literal_comparison,
3155 "comparison with string literal");
3157 build_type = boolean_type_node;
3158 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3159 || code0 == COMPLEX_TYPE)
3160 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3161 || code1 == COMPLEX_TYPE))
3163 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3164 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3165 result_type = composite_pointer_type (type0, type1, op0, op1,
3167 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3168 && null_ptr_cst_p (op1))
3169 result_type = type0;
3170 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3171 && null_ptr_cst_p (op0))
3172 result_type = type1;
3173 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3175 result_type = type0;
3176 error ("ISO C++ forbids comparison between pointer and integer");
3178 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3180 result_type = type1;
3181 error ("ISO C++ forbids comparison between pointer and integer");
3183 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3185 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3186 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3187 result_type = TREE_TYPE (op0);
3189 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3190 return cp_build_binary_op (code, op1, op0);
3191 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
3192 && same_type_p (type0, type1))
3194 /* E will be the final comparison. */
3196 /* E1 and E2 are for scratch. */
3204 if (TREE_SIDE_EFFECTS (op0))
3205 op0 = save_expr (op0);
3206 if (TREE_SIDE_EFFECTS (op1))
3207 op1 = save_expr (op1);
3212 && (!op0.pfn || op0.delta == op1.delta))
3214 The reason for the `!op0.pfn' bit is that a NULL
3215 pointer-to-member is any member with a zero PFN; the
3216 DELTA field is unspecified. */
3217 pfn0 = pfn_from_ptrmemfunc (op0);
3218 pfn1 = pfn_from_ptrmemfunc (op1);
3219 delta0 = build_ptrmemfunc_access_expr (op0,
3221 delta1 = build_ptrmemfunc_access_expr (op1,
3223 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
3224 e2 = cp_build_binary_op (EQ_EXPR,
3226 cp_convert (TREE_TYPE (pfn0),
3227 integer_zero_node));
3228 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
3229 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3230 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3231 if (code == EQ_EXPR)
3233 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3237 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3238 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3240 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3241 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3249 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3250 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3252 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3253 result_type = composite_pointer_type (type0, type1, op0, op1,
3261 if (TREE_CODE (orig_op0) == STRING_CST
3262 || TREE_CODE (orig_op1) == STRING_CST)
3263 warning (OPT_Wstring_literal_comparison,
3264 "comparison with string literal");
3266 build_type = boolean_type_node;
3267 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3268 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3270 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3271 result_type = composite_pointer_type (type0, type1, op0, op1,
3273 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3274 && integer_zerop (op1))
3275 result_type = type0;
3276 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3277 && integer_zerop (op0))
3278 result_type = type1;
3279 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3281 result_type = type0;
3282 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3284 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3286 result_type = type1;
3287 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3291 case UNORDERED_EXPR:
3298 build_type = integer_type_node;
3299 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3301 error ("unordered comparison on non-floating point argument");
3302 return error_mark_node;
3311 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3312 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3313 || code1 == COMPLEX_TYPE)))
3314 arithmetic_types_p = 1;
3317 arithmetic_types_p = 0;
3318 /* Vector arithmetic is only allowed when both sides are vectors. */
3319 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3321 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3322 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3325 binary_op_error (code);
3326 return error_mark_node;
3328 arithmetic_types_p = 1;
3331 /* Determine the RESULT_TYPE, if it is not already known. */
3333 && arithmetic_types_p
3334 && (shorten || common || short_compare))
3335 result_type = common_type (type0, type1);
3339 error ("invalid operands of types %qT and %qT to binary %qO",
3340 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3341 return error_mark_node;
3344 /* If we're in a template, the only thing we need to know is the
3346 if (processing_template_decl)
3347 return build2 (resultcode,
3348 build_type ? build_type : result_type,
3351 if (arithmetic_types_p)
3353 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3355 /* For certain operations (which identify themselves by shorten != 0)
3356 if both args were extended from the same smaller type,
3357 do the arithmetic in that type and then extend.
3359 shorten !=0 and !=1 indicates a bitwise operation.
3360 For them, this optimization is safe only if
3361 both args are zero-extended or both are sign-extended.
3362 Otherwise, we might change the result.
3363 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3364 but calculated in (unsigned short) it would be (unsigned short)-1. */
3366 if (shorten && none_complex)
3368 int unsigned0, unsigned1;
3369 tree arg0 = get_narrower (op0, &unsigned0);
3370 tree arg1 = get_narrower (op1, &unsigned1);
3371 /* UNS is 1 if the operation to be done is an unsigned one. */
3372 int uns = TYPE_UNSIGNED (result_type);
3375 final_type = result_type;
3377 /* Handle the case that OP0 does not *contain* a conversion
3378 but it *requires* conversion to FINAL_TYPE. */
3380 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3381 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
3382 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3383 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
3385 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3387 /* For bitwise operations, signedness of nominal type
3388 does not matter. Consider only how operands were extended. */
3392 /* Note that in all three cases below we refrain from optimizing
3393 an unsigned operation on sign-extended args.
3394 That would not be valid. */
3396 /* Both args variable: if both extended in same way
3397 from same width, do it in that width.
3398 Do it unsigned if args were zero-extended. */
3399 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3400 < TYPE_PRECISION (result_type))
3401 && (TYPE_PRECISION (TREE_TYPE (arg1))
3402 == TYPE_PRECISION (TREE_TYPE (arg0)))
3403 && unsigned0 == unsigned1
3404 && (unsigned0 || !uns))
3405 result_type = c_common_signed_or_unsigned_type
3406 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3407 else if (TREE_CODE (arg0) == INTEGER_CST
3408 && (unsigned1 || !uns)
3409 && (TYPE_PRECISION (TREE_TYPE (arg1))
3410 < TYPE_PRECISION (result_type))
3411 && (type = c_common_signed_or_unsigned_type
3412 (unsigned1, TREE_TYPE (arg1)),
3413 int_fits_type_p (arg0, type)))
3415 else if (TREE_CODE (arg1) == INTEGER_CST
3416 && (unsigned0 || !uns)
3417 && (TYPE_PRECISION (TREE_TYPE (arg0))
3418 < TYPE_PRECISION (result_type))
3419 && (type = c_common_signed_or_unsigned_type
3420 (unsigned0, TREE_TYPE (arg0)),
3421 int_fits_type_p (arg1, type)))
3425 /* Shifts can be shortened if shifting right. */
3430 tree arg0 = get_narrower (op0, &unsigned_arg);
3432 final_type = result_type;
3434 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3435 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
3437 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3438 /* We can shorten only if the shift count is less than the
3439 number of bits in the smaller type size. */
3440 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3441 /* If arg is sign-extended and then unsigned-shifted,
3442 we can simulate this with a signed shift in arg's type
3443 only if the extended result is at least twice as wide
3444 as the arg. Otherwise, the shift could use up all the
3445 ones made by sign-extension and bring in zeros.
3446 We can't optimize that case at all, but in most machines
3447 it never happens because available widths are 2**N. */
3448 && (!TYPE_UNSIGNED (final_type)
3450 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3451 <= TYPE_PRECISION (result_type))))
3453 /* Do an unsigned shift if the operand was zero-extended. */
3455 = c_common_signed_or_unsigned_type (unsigned_arg,
3457 /* Convert value-to-be-shifted to that type. */
3458 if (TREE_TYPE (op0) != result_type)
3459 op0 = cp_convert (result_type, op0);
3464 /* Comparison operations are shortened too but differently.
3465 They identify themselves by setting short_compare = 1. */
3469 /* Don't write &op0, etc., because that would prevent op0
3470 from being kept in a register.
3471 Instead, make copies of the our local variables and
3472 pass the copies by reference, then copy them back afterward. */
3473 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3474 enum tree_code xresultcode = resultcode;
3476 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3478 return cp_convert (boolean_type_node, val);
3479 op0 = xop0, op1 = xop1;
3481 resultcode = xresultcode;
3484 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3485 && warn_sign_compare
3486 /* Do not warn until the template is instantiated; we cannot
3487 bound the ranges of the arguments until that point. */
3488 && !processing_template_decl)
3490 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
3491 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3493 int unsignedp0, unsignedp1;
3494 tree primop0 = get_narrower (op0, &unsignedp0);
3495 tree primop1 = get_narrower (op1, &unsignedp1);
3497 /* Check for comparison of different enum types. */
3498 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3499 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3500 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3501 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3503 warning (0, "comparison between types %q#T and %q#T",
3504 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3507 /* Give warnings for comparisons between signed and unsigned
3508 quantities that may fail. */
3509 /* Do the checking based on the original operand trees, so that
3510 casts will be considered, but default promotions won't be. */
3512 /* Do not warn if the comparison is being done in a signed type,
3513 since the signed type will only be chosen if it can represent
3514 all the values of the unsigned type. */
3515 if (!TYPE_UNSIGNED (result_type))
3517 /* Do not warn if both operands are unsigned. */
3518 else if (op0_signed == op1_signed)
3520 /* Do not warn if the signed quantity is an unsuffixed
3521 integer literal (or some static constant expression
3522 involving such literals or a conditional expression
3523 involving such literals) and it is non-negative. */
3524 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3525 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3527 /* Do not warn if the comparison is an equality operation,
3528 the unsigned quantity is an integral constant and it does
3529 not use the most significant bit of result_type. */
3530 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3531 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3532 && int_fits_type_p (orig_op1, c_common_signed_type
3534 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3535 && int_fits_type_p (orig_op0, c_common_signed_type
3539 warning (0, "comparison between signed and unsigned integer expressions");
3541 /* Warn if two unsigned values are being compared in a size
3542 larger than their original size, and one (and only one) is the
3543 result of a `~' operator. This comparison will always fail.
3545 Also warn if one operand is a constant, and the constant does not
3546 have all bits set that are set in the ~ operand when it is
3549 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3550 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3552 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3553 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3554 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3555 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3557 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3560 HOST_WIDE_INT constant, mask;
3564 if (host_integerp (primop0, 0))
3567 unsignedp = unsignedp1;
3568 constant = tree_low_cst (primop0, 0);
3573 unsignedp = unsignedp0;
3574 constant = tree_low_cst (primop1, 0);
3577 bits = TYPE_PRECISION (TREE_TYPE (primop));
3578 if (bits < TYPE_PRECISION (result_type)
3579 && bits < HOST_BITS_PER_LONG && unsignedp)
3581 mask = (~ (HOST_WIDE_INT) 0) << bits;
3582 if ((mask & constant) != mask)
3583 warning (0, "comparison of promoted ~unsigned with constant");
3586 else if (unsignedp0 && unsignedp1
3587 && (TYPE_PRECISION (TREE_TYPE (primop0))
3588 < TYPE_PRECISION (result_type))
3589 && (TYPE_PRECISION (TREE_TYPE (primop1))
3590 < TYPE_PRECISION (result_type)))
3591 warning (0, "comparison of promoted ~unsigned with unsigned");
3596 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3597 Then the expression will be built.
3598 It will be given type FINAL_TYPE if that is nonzero;
3599 otherwise, it will be given type RESULT_TYPE. */
3601 /* Issue warnings about peculiar, but valid, uses of NULL. */
3602 if (/* It's reasonable to use pointer values as operands of &&
3603 and ||, so NULL is no exception. */
3604 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3605 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3606 (orig_op0 == null_node
3607 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3608 /* Or vice versa. */
3609 || (orig_op1 == null_node
3610 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3611 /* Or, both are NULL and the operation was not a comparison. */
3612 || (orig_op0 == null_node && orig_op1 == null_node
3613 && code != EQ_EXPR && code != NE_EXPR)))
3614 /* Some sort of arithmetic operation involving NULL was
3615 performed. Note that pointer-difference and pointer-addition
3616 have already been handled above, and so we don't end up here in
3618 warning (0, "NULL used in arithmetic");
3622 if (TREE_TYPE (op0) != result_type)
3623 op0 = cp_convert (result_type, op0);
3624 if (TREE_TYPE (op1) != result_type)
3625 op1 = cp_convert (result_type, op1);
3627 if (op0 == error_mark_node || op1 == error_mark_node)
3628 return error_mark_node;
3631 if (build_type == NULL_TREE)
3632 build_type = result_type;
3634 result = build2 (resultcode, build_type, op0, op1);
3635 result = fold_if_not_in_template (result);
3636 if (final_type != 0)
3637 result = cp_convert (final_type, result);
3641 /* Return a tree for the sum or difference (RESULTCODE says which)
3642 of pointer PTROP and integer INTOP. */
3645 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
3647 tree res_type = TREE_TYPE (ptrop);
3649 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3650 in certain circumstance (when it's valid to do so). So we need
3651 to make sure it's complete. We don't need to check here, if we
3652 can actually complete it at all, as those checks will be done in
3653 pointer_int_sum() anyway. */
3654 complete_type (TREE_TYPE (res_type));
3656 return pointer_int_sum (resultcode, ptrop,
3657 fold_if_not_in_template (intop));
3660 /* Return a tree for the difference of pointers OP0 and OP1.
3661 The resulting tree has type int. */
3664 pointer_diff (tree op0, tree op1, tree ptrtype)
3667 tree restype = ptrdiff_type_node;
3668 tree target_type = TREE_TYPE (ptrtype);
3670 if (!complete_type_or_else (target_type, NULL_TREE))
3671 return error_mark_node;
3673 if (pedantic || warn_pointer_arith)
3675 if (TREE_CODE (target_type) == VOID_TYPE)
3676 pedwarn ("ISO C++ forbids using pointer of type %<void *%> in subtraction");
3677 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3678 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3679 if (TREE_CODE (target_type) == METHOD_TYPE)
3680 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3683 /* First do the subtraction as integers;
3684 then drop through to build the divide operator. */
3686 op0 = cp_build_binary_op (MINUS_EXPR,
3687 cp_convert (restype, op0),
3688 cp_convert (restype, op1));
3690 /* This generates an error if op1 is a pointer to an incomplete type. */
3691 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3692 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3694 op1 = (TYPE_PTROB_P (ptrtype)
3695 ? size_in_bytes (target_type)
3696 : integer_one_node);
3698 /* Do the division. */
3700 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3701 return fold_if_not_in_template (result);
3704 /* Construct and perhaps optimize a tree representation
3705 for a unary operation. CODE, a tree_code, specifies the operation
3706 and XARG is the operand. */
3709 build_x_unary_op (enum tree_code code, tree xarg)
3711 tree orig_expr = xarg;
3715 if (processing_template_decl)
3717 if (type_dependent_expression_p (xarg))
3718 return build_min_nt (code, xarg, NULL_TREE);
3720 xarg = build_non_dependent_expr (xarg);
3725 /* [expr.unary.op] says:
3727 The address of an object of incomplete type can be taken.
3729 (And is just the ordinary address operator, not an overloaded
3730 "operator &".) However, if the type is a template
3731 specialization, we must complete the type at this point so that
3732 an overloaded "operator &" will be available if required. */
3733 if (code == ADDR_EXPR
3734 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3735 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
3736 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
3737 || (TREE_CODE (xarg) == OFFSET_REF)))
3738 /* Don't look for a function. */;
3740 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
3741 /*overloaded_p=*/NULL);
3742 if (!exp && code == ADDR_EXPR)
3744 /* A pointer to member-function can be formed only by saying
3746 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3747 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3749 if (TREE_CODE (xarg) != OFFSET_REF
3750 || !TYPE_P (TREE_OPERAND (xarg, 0)))
3752 error ("invalid use of %qE to form a pointer-to-member-function",
3754 if (TREE_CODE (xarg) != OFFSET_REF)
3755 inform (" a qualified-id is required");
3756 return error_mark_node;
3760 error ("parentheses around %qE cannot be used to form a"
3761 " pointer-to-member-function",
3763 PTRMEM_OK_P (xarg) = 1;
3767 if (TREE_CODE (xarg) == OFFSET_REF)
3769 ptrmem = PTRMEM_OK_P (xarg);
3771 if (!ptrmem && !flag_ms_extensions
3772 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3774 /* A single non-static member, make sure we don't allow a
3775 pointer-to-member. */
3776 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
3777 TREE_OPERAND (xarg, 0),
3778 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3779 PTRMEM_OK_P (xarg) = ptrmem;
3782 else if (TREE_CODE (xarg) == TARGET_EXPR)
3783 warning (0, "taking address of temporary");
3784 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3787 if (processing_template_decl && exp != error_mark_node)
3788 exp = build_min_non_dep (code, exp, orig_expr,
3789 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
3790 if (TREE_CODE (exp) == ADDR_EXPR)
3791 PTRMEM_OK_P (exp) = ptrmem;
3795 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3796 constants, where a null value is represented by an INTEGER_CST of
3800 cp_truthvalue_conversion (tree expr)
3802 tree type = TREE_TYPE (expr);
3803 if (TYPE_PTRMEM_P (type))
3804 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3806 return c_common_truthvalue_conversion (expr);
3809 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3812 condition_conversion (tree expr)
3815 if (processing_template_decl)
3817 t = perform_implicit_conversion (boolean_type_node, expr);
3818 t = fold_build_cleanup_point_expr (boolean_type_node, t);
3822 /* Return an ADDR_EXPR giving the address of T. This function
3823 attempts no optimizations or simplifications; it is a low-level
3827 build_address (tree t)
3831 if (error_operand_p (t) || !cxx_mark_addressable (t))
3832 return error_mark_node;
3834 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
3839 /* Return a NOP_EXPR converting EXPR to TYPE. */
3842 build_nop (tree type, tree expr)
3844 if (type == error_mark_node || error_operand_p (expr))
3846 return build1 (NOP_EXPR, type, expr);
3849 /* C++: Must handle pointers to members.
3851 Perhaps type instantiation should be extended to handle conversion
3852 from aggregates to types we don't yet know we want? (Or are those
3853 cases typically errors which should be reported?)
3855 NOCONVERT nonzero suppresses the default promotions
3856 (such as from short to int). */
3859 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3861 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3864 const char *errstring = NULL;
3866 const char *invalid_op_diag;
3868 if (arg == error_mark_node)
3869 return error_mark_node;
3871 if ((invalid_op_diag
3872 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
3877 error (invalid_op_diag);
3878 return error_mark_node;
3883 case UNARY_PLUS_EXPR:
3886 int flags = WANT_ARITH | WANT_ENUM;
3887 /* Unary plus (but not unary minus) is allowed on pointers. */
3888 if (code == UNARY_PLUS_EXPR)
3889 flags |= WANT_POINTER;
3890 arg = build_expr_type_conversion (flags, arg, true);
3892 errstring = (code == NEGATE_EXPR
3893 ? "wrong type argument to unary minus"
3894 : "wrong type argument to unary plus");
3897 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3898 arg = perform_integral_promotions (arg);
3900 /* Make sure the result is not an lvalue: a unary plus or minus
3901 expression is always a rvalue. */
3908 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3912 arg = default_conversion (arg);
3914 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
3916 errstring = "wrong type argument to bit-complement";
3917 else if (!noconvert)
3918 arg = perform_integral_promotions (arg);
3922 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3923 errstring = "wrong type argument to abs";
3924 else if (!noconvert)
3925 arg = default_conversion (arg);
3929 /* Conjugating a real value is a no-op, but allow it anyway. */
3930 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3931 errstring = "wrong type argument to conjugation";
3932 else if (!noconvert)
3933 arg = default_conversion (arg);
3936 case TRUTH_NOT_EXPR:
3937 arg = perform_implicit_conversion (boolean_type_node, arg);
3938 val = invert_truthvalue (arg);
3939 if (arg != error_mark_node)
3941 errstring = "in argument to unary !";
3948 if (TREE_CODE (arg) == COMPLEX_CST)
3949 return TREE_REALPART (arg);
3950 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3952 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3953 return fold_if_not_in_template (arg);
3959 if (TREE_CODE (arg) == COMPLEX_CST)
3960 return TREE_IMAGPART (arg);
3961 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3963 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3964 return fold_if_not_in_template (arg);
3967 return cp_convert (TREE_TYPE (arg), integer_zero_node);
3969 case PREINCREMENT_EXPR:
3970 case POSTINCREMENT_EXPR:
3971 case PREDECREMENT_EXPR:
3972 case POSTDECREMENT_EXPR:
3973 /* Handle complex lvalues (when permitted)
3974 by reduction to simpler cases. */
3976 val = unary_complex_lvalue (code, arg);
3980 /* Increment or decrement the real part of the value,
3981 and don't change the imaginary part. */
3982 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3986 arg = stabilize_reference (arg);
3987 real = build_unary_op (REALPART_EXPR, arg, 1);
3988 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
3989 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
3990 build_unary_op (code, real, 1), imag);
3993 /* Report invalid types. */
3995 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
3998 if (code == PREINCREMENT_EXPR)
3999 errstring ="no pre-increment operator for type";
4000 else if (code == POSTINCREMENT_EXPR)
4001 errstring ="no post-increment operator for type";
4002 else if (code == PREDECREMENT_EXPR)
4003 errstring ="no pre-decrement operator for type";
4005 errstring ="no post-decrement operator for type";
4009 /* Report something read-only. */
4011 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4012 || TREE_READONLY (arg))
4013 readonly_error (arg, ((code == PREINCREMENT_EXPR
4014 || code == POSTINCREMENT_EXPR)
4015 ? "increment" : "decrement"),
4020 tree result_type = TREE_TYPE (arg);
4022 arg = get_unwidened (arg, 0);
4023 argtype = TREE_TYPE (arg);
4025 /* ARM $5.2.5 last annotation says this should be forbidden. */
4026 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4027 pedwarn ("ISO C++ forbids %sing an enum",
4028 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4029 ? "increment" : "decrement");
4031 /* Compute the increment. */
4033 if (TREE_CODE (argtype) == POINTER_TYPE)
4035 tree type = complete_type (TREE_TYPE (argtype));
4037 if (!COMPLETE_OR_VOID_TYPE_P (type))
4038 error ("cannot %s a pointer to incomplete type %qT",
4039 ((code == PREINCREMENT_EXPR
4040 || code == POSTINCREMENT_EXPR)
4041 ? "increment" : "decrement"), TREE_TYPE (argtype));
4042 else if ((pedantic || warn_pointer_arith)
4043 && !TYPE_PTROB_P (argtype))
4044 pedwarn ("ISO C++ forbids %sing a pointer of type %qT",
4045 ((code == PREINCREMENT_EXPR
4046 || code == POSTINCREMENT_EXPR)
4047 ? "increment" : "decrement"), argtype);
4048 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4051 inc = integer_one_node;
4053 inc = cp_convert (argtype, inc);
4055 /* Handle incrementing a cast-expression. */
4057 switch (TREE_CODE (arg))
4062 case FIX_TRUNC_EXPR:
4063 case FIX_FLOOR_EXPR:
4064 case FIX_ROUND_EXPR:
4067 tree incremented, modify, value, compound;
4068 if (! lvalue_p (arg) && pedantic)
4069 pedwarn ("cast to non-reference type used as lvalue");
4070 arg = stabilize_reference (arg);
4071 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
4074 value = save_expr (arg);
4075 incremented = build2 (((code == PREINCREMENT_EXPR
4076 || code == POSTINCREMENT_EXPR)
4077 ? PLUS_EXPR : MINUS_EXPR),
4078 argtype, value, inc);
4080 modify = build_modify_expr (arg, NOP_EXPR, incremented);
4081 compound = build2 (COMPOUND_EXPR, TREE_TYPE (arg),
4084 /* Eliminate warning about unused result of + or -. */
4085 TREE_NO_WARNING (compound) = 1;
4093 /* Complain about anything else that is not a true lvalue. */
4094 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4095 || code == POSTINCREMENT_EXPR)
4096 ? lv_increment : lv_decrement)))
4097 return error_mark_node;
4099 /* Forbid using -- on `bool'. */
4100 if (TREE_TYPE (arg) == boolean_type_node)
4102 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4104 error ("invalid use of %<--%> on bool variable %qD", arg);
4105 return error_mark_node;
4107 val = boolean_increment (code, arg);
4110 val = build2 (code, TREE_TYPE (arg), arg, inc);
4112 TREE_SIDE_EFFECTS (val) = 1;
4113 return cp_convert (result_type, val);
4117 /* Note that this operation never does default_conversion
4118 regardless of NOCONVERT. */
4120 argtype = lvalue_type (arg);
4122 if (TREE_CODE (arg) == OFFSET_REF)
4125 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4127 tree type = build_pointer_type (TREE_TYPE (argtype));
4128 arg = build1 (CONVERT_EXPR, type, arg);
4131 else if (pedantic && DECL_MAIN_P (arg))
4133 pedwarn ("ISO C++ forbids taking address of function %<::main%>");
4135 /* Let &* cancel out to simplify resulting code. */
4136 if (TREE_CODE (arg) == INDIRECT_REF)
4138 /* We don't need to have `current_class_ptr' wrapped in a
4139 NON_LVALUE_EXPR node. */
4140 if (arg == current_class_ref)
4141 return current_class_ptr;
4143 arg = TREE_OPERAND (arg, 0);
4144 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4146 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4147 arg = build1 (CONVERT_EXPR, type, arg);
4150 /* Don't let this be an lvalue. */
4155 /* Uninstantiated types are all functions. Taking the
4156 address of a function is a no-op, so just return the
4159 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4160 || !IDENTIFIER_OPNAME_P (arg));
4162 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4163 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4165 /* They're trying to take the address of a unique non-static
4166 member function. This is ill-formed (except in MS-land),
4167 but let's try to DTRT.
4168 Note: We only handle unique functions here because we don't
4169 want to complain if there's a static overload; non-unique
4170 cases will be handled by instantiate_type. But we need to
4171 handle this case here to allow casts on the resulting PMF.
4172 We could defer this in non-MS mode, but it's easier to give
4173 a useful error here. */
4175 /* Inside constant member functions, the `this' pointer
4176 contains an extra const qualifier. TYPE_MAIN_VARIANT
4177 is used here to remove this const from the diagnostics
4178 and the created OFFSET_REF. */
4179 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4180 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4182 if (! flag_ms_extensions)
4184 tree name = DECL_NAME (fn);
4185 if (current_class_type
4186 && TREE_OPERAND (arg, 0) == current_class_ref)
4187 /* An expression like &memfn. */
4188 pedwarn ("ISO C++ forbids taking the address of an unqualified"
4189 " or parenthesized non-static member function to form"
4190 " a pointer to member function. Say %<&%T::%D%>",
4193 pedwarn ("ISO C++ forbids taking the address of a bound member"
4194 " function to form a pointer to member function."
4198 arg = build_offset_ref (base, fn, /*address_p=*/true);
4202 if (type_unknown_p (arg))
4203 return build1 (ADDR_EXPR, unknown_type_node, arg);
4205 /* Handle complex lvalues (when permitted)
4206 by reduction to simpler cases. */
4207 val = unary_complex_lvalue (code, arg);
4211 switch (TREE_CODE (arg))
4216 case FIX_TRUNC_EXPR:
4217 case FIX_FLOOR_EXPR:
4218 case FIX_ROUND_EXPR:
4220 if (! lvalue_p (arg) && pedantic)
4221 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4225 arg = OVL_CURRENT (arg);
4229 /* Turn a reference to a non-static data member into a
4230 pointer-to-member. */
4235 if (!PTRMEM_OK_P (arg))
4236 return build_unary_op (code, arg, 0);
4238 t = TREE_OPERAND (arg, 1);
4239 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4241 error ("cannot create pointer to reference member %qD", t);
4242 return error_mark_node;
4245 type = build_ptrmem_type (context_for_name_lookup (t),
4247 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4255 /* Anything not already handled and not a true memory reference
4257 if (TREE_CODE (argtype) != FUNCTION_TYPE
4258 && TREE_CODE (argtype) != METHOD_TYPE
4259 && TREE_CODE (arg) != OFFSET_REF
4260 /* Permit users to take the address of a compound-literal
4261 with sufficient simple elements. */
4262 && !(COMPOUND_LITERAL_P (arg) && TREE_STATIC (arg))
4263 && !lvalue_or_else (arg, lv_addressof))
4264 return error_mark_node;
4266 if (argtype != error_mark_node)
4267 argtype = build_pointer_type (argtype);
4269 /* In a template, we are processing a non-dependent expression
4270 so we can just form an ADDR_EXPR with the correct type. */
4271 if (processing_template_decl)
4273 val = build_address (arg);
4274 if (TREE_CODE (arg) == OFFSET_REF)
4275 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4279 /* If the user has taken the address of the compound literal,
4280 create a variable to contain the value of the literal and
4281 then return the address of that variable. */
4282 if (COMPOUND_LITERAL_P (arg))
4285 gcc_assert (TREE_STATIC (arg));
4286 var = create_temporary_var (TREE_TYPE (arg));
4287 TREE_STATIC (var) = 1;
4288 set_compound_literal_name (var);
4289 initialize_artificial_var (var, arg);
4290 arg = pushdecl (var);
4291 /* Since each compound literal is unique, pushdecl should
4292 never find a pre-existing variable with the same
4294 gcc_assert (arg == var);
4297 if (TREE_CODE (arg) != COMPONENT_REF)
4299 val = build_address (arg);
4300 if (TREE_CODE (arg) == OFFSET_REF)
4301 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4303 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4305 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4307 /* We can only get here with a single static member
4309 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4310 && DECL_STATIC_FUNCTION_P (fn));
4312 val = build_address (fn);
4313 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4314 /* Do not lose object's side effects. */
4315 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4316 TREE_OPERAND (arg, 0), val);
4318 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4320 error ("attempt to take address of bit-field structure member %qD",
4321 TREE_OPERAND (arg, 1));
4322 return error_mark_node;
4326 tree object = TREE_OPERAND (arg, 0);
4327 tree field = TREE_OPERAND (arg, 1);
4328 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4329 (TREE_TYPE (object), decl_type_context (field)));
4330 val = build_address (arg);
4333 if (TREE_CODE (argtype) == POINTER_TYPE
4334 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4336 build_ptrmemfunc_type (argtype);
4337 val = build_ptrmemfunc (argtype, val, 0,
4338 /*c_cast_p=*/false);
4350 argtype = TREE_TYPE (arg);
4351 return fold_if_not_in_template (build1 (code, argtype, arg));
4354 error ("%s", errstring);
4355 return error_mark_node;
4358 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4359 for certain kinds of expressions which are not really lvalues
4360 but which we can accept as lvalues.
4362 If ARG is not a kind of expression we can handle, return
4366 unary_complex_lvalue (enum tree_code code, tree arg)
4368 /* Inside a template, making these kinds of adjustments is
4369 pointless; we are only concerned with the type of the
4371 if (processing_template_decl)
4374 /* Handle (a, b) used as an "lvalue". */
4375 if (TREE_CODE (arg) == COMPOUND_EXPR)
4377 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4378 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4379 TREE_OPERAND (arg, 0), real_result);
4382 /* Handle (a ? b : c) used as an "lvalue". */
4383 if (TREE_CODE (arg) == COND_EXPR
4384 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4385 return rationalize_conditional_expr (code, arg);
4387 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4388 if (TREE_CODE (arg) == MODIFY_EXPR
4389 || TREE_CODE (arg) == PREINCREMENT_EXPR
4390 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4392 tree lvalue = TREE_OPERAND (arg, 0);
4393 if (TREE_SIDE_EFFECTS (lvalue))
4395 lvalue = stabilize_reference (lvalue);
4396 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4397 lvalue, TREE_OPERAND (arg, 1));
4399 return unary_complex_lvalue
4400 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4403 if (code != ADDR_EXPR)
4406 /* Handle (a = b) used as an "lvalue" for `&'. */
4407 if (TREE_CODE (arg) == MODIFY_EXPR
4408 || TREE_CODE (arg) == INIT_EXPR)
4410 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4411 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4413 TREE_NO_WARNING (arg) = 1;
4417 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4418 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4419 || TREE_CODE (arg) == OFFSET_REF)
4422 /* We permit compiler to make function calls returning
4423 objects of aggregate type look like lvalues. */
4427 if (TREE_CODE (targ) == SAVE_EXPR)
4428 targ = TREE_OPERAND (targ, 0);
4430 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4432 if (TREE_CODE (arg) == SAVE_EXPR)
4435 targ = build_cplus_new (TREE_TYPE (arg), arg);
4436 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4439 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4440 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4441 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4444 /* Don't let anything else be handled specially. */
4448 /* Mark EXP saying that we need to be able to take the
4449 address of it; it should not be allocated in a register.
4450 Value is true if successful.
4452 C++: we do not allow `current_class_ptr' to be addressable. */
4455 cxx_mark_addressable (tree exp)
4460 switch (TREE_CODE (x))
4467 x = TREE_OPERAND (x, 0);
4471 if (x == current_class_ptr)
4473 error ("cannot take the address of %<this%>, which is an rvalue expression");
4474 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4480 /* Caller should not be trying to mark initialized
4481 constant fields addressable. */
4482 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4483 || DECL_IN_AGGR_P (x) == 0
4485 || DECL_EXTERNAL (x));
4490 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4491 && !DECL_ARTIFICIAL (x))
4493 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4496 ("address of explicit register variable %qD requested", x);
4499 else if (extra_warnings)
4501 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
4503 TREE_ADDRESSABLE (x) = 1;
4507 TREE_ADDRESSABLE (x) = 1;
4511 TREE_ADDRESSABLE (x) = 1;
4515 TREE_ADDRESSABLE (x) = 1;
4516 cxx_mark_addressable (TREE_OPERAND (x, 0));
4524 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4527 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4529 tree orig_ifexp = ifexp;
4530 tree orig_op1 = op1;
4531 tree orig_op2 = op2;
4534 if (processing_template_decl)
4536 /* The standard says that the expression is type-dependent if
4537 IFEXP is type-dependent, even though the eventual type of the
4538 expression doesn't dependent on IFEXP. */
4539 if (type_dependent_expression_p (ifexp)
4540 /* As a GNU extension, the middle operand may be omitted. */
4541 || (op1 && type_dependent_expression_p (op1))
4542 || type_dependent_expression_p (op2))
4543 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4544 ifexp = build_non_dependent_expr (ifexp);
4546 op1 = build_non_dependent_expr (op1);
4547 op2 = build_non_dependent_expr (op2);
4550 expr = build_conditional_expr (ifexp, op1, op2);
4551 if (processing_template_decl && expr != error_mark_node)
4552 return build_min_non_dep (COND_EXPR, expr,
4553 orig_ifexp, orig_op1, orig_op2);
4557 /* Given a list of expressions, return a compound expression
4558 that performs them all and returns the value of the last of them. */
4560 tree build_x_compound_expr_from_list (tree list, const char *msg)
4562 tree expr = TREE_VALUE (list);
4564 if (TREE_CHAIN (list))
4567 pedwarn ("%s expression list treated as compound expression", msg);
4569 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4570 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4576 /* Handle overloading of the ',' operator when needed. */
4579 build_x_compound_expr (tree op1, tree op2)
4582 tree orig_op1 = op1;
4583 tree orig_op2 = op2;
4585 if (processing_template_decl)
4587 if (type_dependent_expression_p (op1)
4588 || type_dependent_expression_p (op2))
4589 return build_min_nt (COMPOUND_EXPR, op1, op2);
4590 op1 = build_non_dependent_expr (op1);
4591 op2 = build_non_dependent_expr (op2);
4594 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4595 /*overloaded_p=*/NULL);
4597 result = build_compound_expr (op1, op2);
4599 if (processing_template_decl && result != error_mark_node)
4600 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4605 /* Build a compound expression. */
4608 build_compound_expr (tree lhs, tree rhs)
4610 lhs = convert_to_void (lhs, "left-hand operand of comma");
4612 if (lhs == error_mark_node || rhs == error_mark_node)
4613 return error_mark_node;
4615 if (TREE_CODE (rhs) == TARGET_EXPR)
4617 /* If the rhs is a TARGET_EXPR, then build the compound
4618 expression inside the target_expr's initializer. This
4619 helps the compiler to eliminate unnecessary temporaries. */
4620 tree init = TREE_OPERAND (rhs, 1);
4622 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4623 TREE_OPERAND (rhs, 1) = init;
4628 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4631 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
4632 casts away constness. DIAG_FN gives the function to call if we
4633 need to issue a diagnostic; if it is NULL, no diagnostic will be
4634 issued. DESCRIPTION explains what operation is taking place. */
4637 check_for_casting_away_constness (tree src_type, tree dest_type,
4638 void (*diag_fn)(const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2),
4639 const char *description)
4641 if (diag_fn && casts_away_constness (src_type, dest_type))
4642 diag_fn ("%s from type %qT to type %qT casts away constness",
4643 description, src_type, dest_type);
4646 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
4647 (another pointer-to-member type in the same hierarchy) and return
4648 the converted expression. If ALLOW_INVERSE_P is permitted, a
4649 pointer-to-derived may be converted to pointer-to-base; otherwise,
4650 only the other direction is permitted. If C_CAST_P is true, this
4651 conversion is taking place as part of a C-style cast. */
4654 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
4657 if (TYPE_PTRMEM_P (type))
4661 if (TREE_CODE (expr) == PTRMEM_CST)
4662 expr = cplus_expand_constant (expr);
4663 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
4664 TYPE_PTRMEM_CLASS_TYPE (type),
4667 if (!integer_zerop (delta))
4668 expr = cp_build_binary_op (PLUS_EXPR,
4669 build_nop (ptrdiff_type_node, expr),
4671 return build_nop (type, expr);
4674 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4675 allow_inverse_p, c_cast_p);
4678 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
4679 a version of EXPR that has TREE_OVERFLOW and/or TREE_CONSTANT_OVERFLOW
4680 set iff they are set in ORIG. Otherwise, return EXPR unchanged. */
4683 ignore_overflows (tree expr, tree orig)
4685 if (TREE_CODE (expr) == INTEGER_CST
4686 && CONSTANT_CLASS_P (orig)
4687 && TREE_CODE (orig) != STRING_CST
4688 && (TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig)
4689 || TREE_CONSTANT_OVERFLOW (expr)
4690 != TREE_CONSTANT_OVERFLOW (orig)))
4692 if (!TREE_OVERFLOW (orig) && !TREE_CONSTANT_OVERFLOW (orig))
4693 /* Ensure constant sharing. */
4694 expr = build_int_cst_wide (TREE_TYPE (expr),
4695 TREE_INT_CST_LOW (expr),
4696 TREE_INT_CST_HIGH (expr));
4699 /* Avoid clobbering a shared constant. */
4700 expr = copy_node (expr);
4701 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
4702 TREE_CONSTANT_OVERFLOW (expr)
4703 = TREE_CONSTANT_OVERFLOW (orig);
4709 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
4710 this static_cast is being attempted as one of the possible casts
4711 allowed by a C-style cast. (In that case, accessibility of base
4712 classes is not considered, and it is OK to cast away
4713 constness.) Return the result of the cast. *VALID_P is set to
4714 indicate whether or not the cast was valid. */
4717 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
4723 void (*diag_fn)(const char*, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
4726 /* Assume the cast is valid. */
4729 intype = TREE_TYPE (expr);
4731 /* Determine what to do when casting away constness. */
4734 /* C-style casts are allowed to cast away constness. With
4735 WARN_CAST_QUAL, we still want to issue a warning. */
4736 diag_fn = warn_cast_qual ? warning0 : NULL;
4741 /* A static_cast may not cast away constness. */
4743 desc = "static_cast";
4746 /* [expr.static.cast]
4748 An lvalue of type "cv1 B", where B is a class type, can be cast
4749 to type "reference to cv2 D", where D is a class derived (clause
4750 _class.derived_) from B, if a valid standard conversion from
4751 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4752 same cv-qualification as, or greater cv-qualification than, cv1,
4753 and B is not a virtual base class of D. */
4754 /* We check this case before checking the validity of "TYPE t =
4755 EXPR;" below because for this case:
4758 struct D : public B { D(const B&); };
4760 void f() { static_cast<const D&>(b); }
4762 we want to avoid constructing a new D. The standard is not
4763 completely clear about this issue, but our interpretation is
4764 consistent with other compilers. */
4765 if (TREE_CODE (type) == REFERENCE_TYPE
4766 && CLASS_TYPE_P (TREE_TYPE (type))
4767 && CLASS_TYPE_P (intype)
4768 && real_lvalue_p (expr)
4769 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4770 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4771 build_pointer_type (TYPE_MAIN_VARIANT
4772 (TREE_TYPE (type))))
4774 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
4778 /* There is a standard conversion from "D*" to "B*" even if "B"
4779 is ambiguous or inaccessible. If this is really a
4780 static_cast, then we check both for inaccessibility and
4781 ambiguity. However, if this is a static_cast being performed
4782 because the user wrote a C-style cast, then accessibility is
4784 base = lookup_base (TREE_TYPE (type), intype,
4785 c_cast_p ? ba_unique : ba_check,
4788 /* Convert from "B*" to "D*". This function will check that "B"
4789 is not a virtual base of "D". */
4790 expr = build_base_path (MINUS_EXPR, build_address (expr),
4791 base, /*nonnull=*/false);
4792 /* Convert the pointer to a reference -- but then remember that
4793 there are no expressions with reference type in C++. */
4794 return convert_from_reference (build_nop (type, expr));
4799 /* [expr.static.cast]
4801 An expression e can be explicitly converted to a type T using a
4802 static_cast of the form static_cast<T>(e) if the declaration T
4803 t(e);" is well-formed, for some invented temporary variable
4805 result = perform_direct_initialization_if_possible (type, expr,
4809 result = convert_from_reference (result);
4811 /* Ignore any integer overflow caused by the cast. */
4812 result = ignore_overflows (result, orig);
4814 /* [expr.static.cast]
4816 If T is a reference type, the result is an lvalue; otherwise,
4817 the result is an rvalue. */
4818 if (TREE_CODE (type) != REFERENCE_TYPE)
4819 result = rvalue (result);
4823 /* [expr.static.cast]
4825 Any expression can be explicitly converted to type cv void. */
4826 if (TREE_CODE (type) == VOID_TYPE)
4827 return convert_to_void (expr, /*implicit=*/NULL);
4829 /* [expr.static.cast]
4831 The inverse of any standard conversion sequence (clause _conv_),
4832 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4833 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4834 (_conv.bool_) conversions, can be performed explicitly using
4835 static_cast subject to the restriction that the explicit
4836 conversion does not cast away constness (_expr.const.cast_), and
4837 the following additional rules for specific cases: */
4838 /* For reference, the conversions not excluded are: integral
4839 promotions, floating point promotion, integral conversions,
4840 floating point conversions, floating-integral conversions,
4841 pointer conversions, and pointer to member conversions. */
4844 A value of integral _or enumeration_ type can be explicitly
4845 converted to an enumeration type. */
4846 /* The effect of all that is that any conversion between any two
4847 types which are integral, floating, or enumeration types can be
4849 if ((INTEGRAL_TYPE_P (type) || SCALAR_FLOAT_TYPE_P (type))
4850 && (INTEGRAL_TYPE_P (intype) || SCALAR_FLOAT_TYPE_P (intype)))
4852 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
4854 /* Ignore any integer overflow caused by the cast. */
4855 expr = ignore_overflows (expr, orig);
4859 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4860 && CLASS_TYPE_P (TREE_TYPE (type))
4861 && CLASS_TYPE_P (TREE_TYPE (intype))
4862 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4863 (TREE_TYPE (intype))),
4864 build_pointer_type (TYPE_MAIN_VARIANT
4865 (TREE_TYPE (type)))))
4870 check_for_casting_away_constness (intype, type, diag_fn, desc);
4871 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
4872 c_cast_p ? ba_unique : ba_check,
4874 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4877 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4878 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4885 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4886 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4888 if (TYPE_PTRMEM_P (type))
4890 t1 = (build_ptrmem_type
4892 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4893 t2 = (build_ptrmem_type
4895 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4902 if (can_convert (t1, t2))
4905 check_for_casting_away_constness (intype, type, diag_fn,
4907 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
4912 /* [expr.static.cast]
4914 An rvalue of type "pointer to cv void" can be explicitly
4915 converted to a pointer to object type. A value of type pointer
4916 to object converted to "pointer to cv void" and back to the
4917 original pointer type will have its original value. */
4918 if (TREE_CODE (intype) == POINTER_TYPE
4919 && VOID_TYPE_P (TREE_TYPE (intype))
4920 && TYPE_PTROB_P (type))
4923 check_for_casting_away_constness (intype, type, diag_fn, desc);
4924 return build_nop (type, expr);
4928 return error_mark_node;
4931 /* Return an expression representing static_cast<TYPE>(EXPR). */
4934 build_static_cast (tree type, tree expr)
4939 if (type == error_mark_node || expr == error_mark_node)
4940 return error_mark_node;
4942 if (processing_template_decl)
4944 expr = build_min (STATIC_CAST_EXPR, type, expr);
4945 /* We don't know if it will or will not have side effects. */
4946 TREE_SIDE_EFFECTS (expr) = 1;
4947 return convert_from_reference (expr);
4950 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4951 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4952 if (TREE_CODE (type) != REFERENCE_TYPE
4953 && TREE_CODE (expr) == NOP_EXPR
4954 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4955 expr = TREE_OPERAND (expr, 0);
4957 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p);
4961 error ("invalid static_cast from type %qT to type %qT",
4962 TREE_TYPE (expr), type);
4963 return error_mark_node;
4966 /* EXPR is an expression with member function or pointer-to-member
4967 function type. TYPE is a pointer type. Converting EXPR to TYPE is
4968 not permitted by ISO C++, but we accept it in some modes. If we
4969 are not in one of those modes, issue a diagnostic. Return the
4970 converted expression. */
4973 convert_member_func_to_ptr (tree type, tree expr)
4978 intype = TREE_TYPE (expr);
4979 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
4980 || TREE_CODE (intype) == METHOD_TYPE);
4982 if (pedantic || warn_pmf2ptr)
4983 pedwarn ("converting from %qT to %qT", intype, type);
4985 if (TREE_CODE (intype) == METHOD_TYPE)
4986 expr = build_addr_func (expr);
4987 else if (TREE_CODE (expr) == PTRMEM_CST)
4988 expr = build_address (PTRMEM_CST_MEMBER (expr));
4991 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
4992 decl = build_address (decl);
4993 expr = get_member_function_from_ptrfunc (&decl, expr);
4996 return build_nop (type, expr);
4999 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5000 If C_CAST_P is true, this reinterpret cast is being done as part of
5001 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5002 indicate whether or not reinterpret_cast was valid. */
5005 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5010 /* Assume the cast is invalid. */
5014 if (type == error_mark_node || error_operand_p (expr))
5015 return error_mark_node;
5017 intype = TREE_TYPE (expr);
5019 /* [expr.reinterpret.cast]
5020 An lvalue expression of type T1 can be cast to the type
5021 "reference to T2" if an expression of type "pointer to T1" can be
5022 explicitly converted to the type "pointer to T2" using a
5023 reinterpret_cast. */
5024 if (TREE_CODE (type) == REFERENCE_TYPE)
5026 if (! real_lvalue_p (expr))
5028 error ("invalid cast of an rvalue expression of type "
5031 return error_mark_node;
5034 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5035 "B" are related class types; the reinterpret_cast does not
5036 adjust the pointer. */
5037 if (TYPE_PTR_P (intype)
5038 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5039 COMPARE_BASE | COMPARE_DERIVED)))
5040 warning (0, "casting %qT to %qT does not dereference pointer",
5043 expr = build_unary_op (ADDR_EXPR, expr, 0);
5044 if (expr != error_mark_node)
5045 expr = build_reinterpret_cast_1
5046 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5048 if (expr != error_mark_node)
5049 expr = build_indirect_ref (expr, 0);
5053 /* As a G++ extension, we consider conversions from member
5054 functions, and pointers to member functions to
5055 pointer-to-function and pointer-to-void types. If
5056 -Wno-pmf-conversions has not been specified,
5057 convert_member_func_to_ptr will issue an error message. */
5058 if ((TYPE_PTRMEMFUNC_P (intype)
5059 || TREE_CODE (intype) == METHOD_TYPE)
5060 && TYPE_PTR_P (type)
5061 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5062 || VOID_TYPE_P (TREE_TYPE (type))))
5063 return convert_member_func_to_ptr (type, expr);
5065 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5066 array-to-pointer, and function-to-pointer conversions are
5068 expr = decay_conversion (expr);
5070 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5071 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5072 if (TREE_CODE (expr) == NOP_EXPR
5073 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5074 expr = TREE_OPERAND (expr, 0);
5076 if (error_operand_p (expr))
5077 return error_mark_node;
5079 intype = TREE_TYPE (expr);
5081 /* [expr.reinterpret.cast]
5082 A pointer can be converted to any integral type large enough to
5084 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5086 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5087 pedwarn ("cast from %qT to %qT loses precision",
5090 /* [expr.reinterpret.cast]
5091 A value of integral or enumeration type can be explicitly
5092 converted to a pointer. */
5093 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5096 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5097 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5098 return fold_if_not_in_template (build_nop (type, expr));
5099 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5100 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5105 check_for_casting_away_constness (intype, type, error,
5106 "reinterpret_cast");
5107 /* Warn about possible alignment problems. */
5108 if (STRICT_ALIGNMENT && warn_cast_align
5109 && !VOID_TYPE_P (type)
5110 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5111 && COMPLETE_TYPE_P (TREE_TYPE (type))
5112 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5113 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5114 warning (0, "cast from %qT to %qT increases required alignment of "
5118 /* We need to strip nops here, because the frontend likes to
5119 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5121 strict_aliasing_warning (intype, type, sexpr);
5123 return fold_if_not_in_template (build_nop (type, expr));
5125 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5126 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5129 /* Only issue a warning, as we have always supported this
5130 where possible, and it is necessary in some cases. DR 195
5131 addresses this issue, but as of 2004/10/26 is still in
5133 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5134 return fold_if_not_in_template (build_nop (type, expr));
5136 else if (TREE_CODE (type) == VECTOR_TYPE)
5137 return fold_if_not_in_template (convert_to_vector (type, expr));
5138 else if (TREE_CODE (intype) == VECTOR_TYPE)
5139 return fold_if_not_in_template (convert_to_integer (type, expr));
5144 error ("invalid cast from type %qT to type %qT", intype, type);
5145 return error_mark_node;
5148 return cp_convert (type, expr);
5152 build_reinterpret_cast (tree type, tree expr)
5154 if (type == error_mark_node || expr == error_mark_node)
5155 return error_mark_node;
5157 if (processing_template_decl)
5159 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5161 if (!TREE_SIDE_EFFECTS (t)
5162 && type_dependent_expression_p (expr))
5163 /* There might turn out to be side effects inside expr. */
5164 TREE_SIDE_EFFECTS (t) = 1;
5165 return convert_from_reference (t);
5168 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5172 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5173 return an appropriate expression. Otherwise, return
5174 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5175 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5176 performing a C-style cast, its value upon return will indicate
5177 whether or not the conversion succeeded. */
5180 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5184 tree reference_type;
5186 /* Callers are responsible for handling error_mark_node as a
5187 destination type. */
5188 gcc_assert (dst_type != error_mark_node);
5189 /* In a template, callers should be building syntactic
5190 representations of casts, not using this machinery. */
5191 gcc_assert (!processing_template_decl);
5193 /* Assume the conversion is invalid. */
5197 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5200 error ("invalid use of const_cast with type %qT, "
5201 "which is not a pointer, "
5202 "reference, nor a pointer-to-data-member type", dst_type);
5203 return error_mark_node;
5206 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5209 error ("invalid use of const_cast with type %qT, which is a pointer "
5210 "or reference to a function type", dst_type);
5211 return error_mark_node;
5214 src_type = TREE_TYPE (expr);
5215 /* Expressions do not really have reference types. */
5216 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5217 src_type = TREE_TYPE (src_type);
5219 /* [expr.const.cast]
5221 An lvalue of type T1 can be explicitly converted to an lvalue of
5222 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5223 types) if a pointer to T1 can be explicitly converted to the type
5224 pointer to T2 using a const_cast. */
5225 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5227 reference_type = dst_type;
5228 if (! real_lvalue_p (expr))
5231 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5232 src_type, dst_type);
5233 return error_mark_node;
5235 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5236 src_type = build_pointer_type (src_type);
5240 reference_type = NULL_TREE;
5241 /* If the destination type is not a reference type, the
5242 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5243 conversions are performed. */
5244 src_type = type_decays_to (src_type);
5245 if (src_type == error_mark_node)
5246 return error_mark_node;
5249 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5250 && comp_ptr_ttypes_const (dst_type, src_type))
5255 /* This cast is actually a C-style cast. Issue a warning if
5256 the user is making a potentially unsafe cast. */
5258 check_for_casting_away_constness (src_type, dst_type,
5264 expr = build_unary_op (ADDR_EXPR, expr, 0);
5265 expr = build_nop (reference_type, expr);
5266 return convert_from_reference (expr);
5270 expr = decay_conversion (expr);
5271 /* build_c_cast puts on a NOP_EXPR to make the result not an
5272 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5273 non-lvalue context. */
5274 if (TREE_CODE (expr) == NOP_EXPR
5275 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5276 expr = TREE_OPERAND (expr, 0);
5277 return build_nop (dst_type, expr);
5282 error ("invalid const_cast from type %qT to type %qT",
5283 src_type, dst_type);
5284 return error_mark_node;
5288 build_const_cast (tree type, tree expr)
5290 if (type == error_mark_node || error_operand_p (expr))
5291 return error_mark_node;
5293 if (processing_template_decl)
5295 tree t = build_min (CONST_CAST_EXPR, type, expr);
5297 if (!TREE_SIDE_EFFECTS (t)
5298 && type_dependent_expression_p (expr))
5299 /* There might turn out to be side effects inside expr. */
5300 TREE_SIDE_EFFECTS (t) = 1;
5301 return convert_from_reference (t);
5304 return build_const_cast_1 (type, expr, /*complain=*/true,
5308 /* Build an expression representing an explicit C-style cast to type
5309 TYPE of expression EXPR. */
5312 build_c_cast (tree type, tree expr)
5318 if (type == error_mark_node || error_operand_p (expr))
5319 return error_mark_node;
5321 if (processing_template_decl)
5323 tree t = build_min (CAST_EXPR, type,
5324 tree_cons (NULL_TREE, value, NULL_TREE));
5325 /* We don't know if it will or will not have side effects. */
5326 TREE_SIDE_EFFECTS (t) = 1;
5327 return convert_from_reference (t);
5330 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5331 'Class') should always be retained, because this information aids
5332 in method lookup. */
5333 if (objc_is_object_ptr (type)
5334 && objc_is_object_ptr (TREE_TYPE (expr)))
5335 return build_nop (type, expr);
5337 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5338 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5339 if (TREE_CODE (type) != REFERENCE_TYPE
5340 && TREE_CODE (value) == NOP_EXPR
5341 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5342 value = TREE_OPERAND (value, 0);
5344 if (TREE_CODE (type) == ARRAY_TYPE)
5346 /* Allow casting from T1* to T2[] because Cfront allows it.
5347 NIHCL uses it. It is not valid ISO C++ however. */
5348 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5350 pedwarn ("ISO C++ forbids casting to an array type %qT", type);
5351 type = build_pointer_type (TREE_TYPE (type));
5355 error ("ISO C++ forbids casting to an array type %qT", type);
5356 return error_mark_node;
5360 if (TREE_CODE (type) == FUNCTION_TYPE
5361 || TREE_CODE (type) == METHOD_TYPE)
5363 error ("invalid cast to function type %qT", type);
5364 return error_mark_node;
5367 /* A C-style cast can be a const_cast. */
5368 result = build_const_cast_1 (type, value, /*complain=*/false,
5373 /* Or a static cast. */
5374 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5376 /* Or a reinterpret_cast. */
5378 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5380 /* The static_cast or reinterpret_cast may be followed by a
5383 /* A valid cast may result in errors if, for example, a
5384 conversion to am ambiguous base class is required. */
5385 && !error_operand_p (result))
5389 /* Non-class rvalues always have cv-unqualified type. */
5390 if (!CLASS_TYPE_P (type))
5391 type = TYPE_MAIN_VARIANT (type);
5392 result_type = TREE_TYPE (result);
5393 if (!CLASS_TYPE_P (result_type))
5394 result_type = TYPE_MAIN_VARIANT (result_type);
5395 /* If the type of RESULT does not match TYPE, perform a
5396 const_cast to make it match. If the static_cast or
5397 reinterpret_cast succeeded, we will differ by at most
5398 cv-qualification, so the follow-on const_cast is guaranteed
5400 if (!same_type_p (non_reference (type), non_reference (result_type)))
5402 result = build_const_cast_1 (type, result, false, &valid_p);
5403 gcc_assert (valid_p);
5408 return error_mark_node;
5411 /* Build an assignment expression of lvalue LHS from value RHS.
5412 MODIFYCODE is the code for a binary operator that we use
5413 to combine the old value of LHS with RHS to get the new value.
5414 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5416 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5419 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5423 tree lhstype = TREE_TYPE (lhs);
5424 tree olhstype = lhstype;
5425 tree olhs = NULL_TREE;
5426 bool plain_assign = (modifycode == NOP_EXPR);
5428 /* Avoid duplicate error messages from operands that had errors. */
5429 if (lhs == error_mark_node || rhs == error_mark_node)
5430 return error_mark_node;
5432 /* Handle control structure constructs used as "lvalues". */
5433 switch (TREE_CODE (lhs))
5435 /* Handle --foo = 5; as these are valid constructs in C++. */
5436 case PREDECREMENT_EXPR:
5437 case PREINCREMENT_EXPR:
5438 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5439 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5440 stabilize_reference (TREE_OPERAND (lhs, 0)),
5441 TREE_OPERAND (lhs, 1));
5442 return build2 (COMPOUND_EXPR, lhstype,
5444 build_modify_expr (TREE_OPERAND (lhs, 0),
5447 /* Handle (a, b) used as an "lvalue". */
5449 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
5451 if (newrhs == error_mark_node)
5452 return error_mark_node;
5453 return build2 (COMPOUND_EXPR, lhstype,
5454 TREE_OPERAND (lhs, 0), newrhs);
5457 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5458 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5459 stabilize_reference (TREE_OPERAND (lhs, 0)),
5460 TREE_OPERAND (lhs, 1));
5461 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
5462 if (newrhs == error_mark_node)
5463 return error_mark_node;
5464 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5468 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
5469 when neither operand has side-effects. */
5470 if (!lvalue_or_else (lhs, lv_assign))
5471 return error_mark_node;
5473 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
5474 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
5476 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
5477 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
5479 TREE_OPERAND (lhs, 0),
5480 TREE_OPERAND (lhs, 1)),
5481 TREE_OPERAND (lhs, 0),
5482 TREE_OPERAND (lhs, 1));
5485 /* Handle (a ? b : c) used as an "lvalue". */
5488 /* Produce (a ? (b = rhs) : (c = rhs))
5489 except that the RHS goes through a save-expr
5490 so the code to compute it is only emitted once. */
5492 tree preeval = NULL_TREE;
5494 rhs = stabilize_expr (rhs, &preeval);
5496 /* Check this here to avoid odd errors when trying to convert
5497 a throw to the type of the COND_EXPR. */
5498 if (!lvalue_or_else (lhs, lv_assign))
5499 return error_mark_node;
5501 cond = build_conditional_expr
5502 (TREE_OPERAND (lhs, 0),
5503 build_modify_expr (cp_convert (TREE_TYPE (lhs),
5504 TREE_OPERAND (lhs, 1)),
5506 build_modify_expr (cp_convert (TREE_TYPE (lhs),
5507 TREE_OPERAND (lhs, 2)),
5510 if (cond == error_mark_node)
5512 /* Make sure the code to compute the rhs comes out
5513 before the split. */
5515 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5523 if (modifycode == INIT_EXPR)
5525 if (TREE_CODE (rhs) == CONSTRUCTOR)
5527 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5528 /* Call convert to generate an error; see PR 11063. */
5529 rhs = convert (lhstype, rhs);
5530 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
5531 TREE_SIDE_EFFECTS (result) = 1;
5534 else if (! IS_AGGR_TYPE (lhstype))
5535 /* Do the default thing. */;
5538 result = build_special_member_call (lhs, complete_ctor_identifier,
5539 build_tree_list (NULL_TREE, rhs),
5540 lhstype, LOOKUP_NORMAL);
5541 if (result == NULL_TREE)
5542 return error_mark_node;
5548 lhs = require_complete_type (lhs);
5549 if (lhs == error_mark_node)
5550 return error_mark_node;
5552 if (modifycode == NOP_EXPR)
5554 /* `operator=' is not an inheritable operator. */
5555 if (! IS_AGGR_TYPE (lhstype))
5556 /* Do the default thing. */;
5559 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5560 lhs, rhs, make_node (NOP_EXPR),
5561 /*overloaded_p=*/NULL);
5562 if (result == NULL_TREE)
5563 return error_mark_node;
5570 /* A binary op has been requested. Combine the old LHS
5571 value with the RHS producing the value we should actually
5572 store into the LHS. */
5574 gcc_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE));
5575 lhs = stabilize_reference (lhs);
5576 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
5577 if (newrhs == error_mark_node)
5579 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
5580 TREE_TYPE (lhs), TREE_TYPE (rhs));
5581 return error_mark_node;
5584 /* Now it looks like a plain assignment. */
5585 modifycode = NOP_EXPR;
5587 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
5588 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
5591 /* The left-hand side must be an lvalue. */
5592 if (!lvalue_or_else (lhs, lv_assign))
5593 return error_mark_node;
5595 /* Warn about modifying something that is `const'. Don't warn if
5596 this is initialization. */
5597 if (modifycode != INIT_EXPR
5598 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5599 /* Functions are not modifiable, even though they are
5601 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5602 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5603 /* If it's an aggregate and any field is const, then it is
5604 effectively const. */
5605 || (CLASS_TYPE_P (lhstype)
5606 && C_TYPE_FIELDS_READONLY (lhstype))))
5607 readonly_error (lhs, "assignment", 0);
5609 /* If storing into a structure or union member, it has probably been
5610 given type `int'. Compute the type that would go with the actual
5611 amount of storage the member occupies. */
5613 if (TREE_CODE (lhs) == COMPONENT_REF
5614 && (TREE_CODE (lhstype) == INTEGER_TYPE
5615 || TREE_CODE (lhstype) == REAL_TYPE
5616 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5618 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5620 /* If storing in a field that is in actuality a short or narrower
5621 than one, we must store in the field in its actual type. */
5623 if (lhstype != TREE_TYPE (lhs))
5625 /* Avoid warnings converting integral types back into enums for
5627 if (TREE_CODE (lhstype) == INTEGER_TYPE
5628 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5630 if (TREE_SIDE_EFFECTS (lhs))
5631 lhs = stabilize_reference (lhs);
5634 lhs = copy_node (lhs);
5635 TREE_TYPE (lhs) = lhstype;
5639 /* Convert new value to destination type. */
5641 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5645 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5646 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5648 error ("incompatible types in assignment of %qT to %qT",
5649 TREE_TYPE (rhs), lhstype);
5650 return error_mark_node;
5653 /* Allow array assignment in compiler-generated code. */
5654 if (! DECL_ARTIFICIAL (current_function_decl))
5655 pedwarn ("ISO C++ forbids assignment of arrays");
5657 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5658 ? 1 + (modifycode != INIT_EXPR): 0;
5659 return build_vec_init (lhs, NULL_TREE, newrhs,
5660 /*explicit_default_init_p=*/false,
5664 if (modifycode == INIT_EXPR)
5665 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5666 "initialization", NULL_TREE, 0);
5669 /* Avoid warnings on enum bit fields. */
5670 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5671 && TREE_CODE (lhstype) == INTEGER_TYPE)
5673 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5675 newrhs = convert_force (lhstype, newrhs, 0);
5678 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5680 if (TREE_CODE (newrhs) == CALL_EXPR
5681 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5682 newrhs = build_cplus_new (lhstype, newrhs);
5684 /* Can't initialize directly from a TARGET_EXPR, since that would
5685 cause the lhs to be constructed twice, and possibly result in
5686 accidental self-initialization. So we force the TARGET_EXPR to be
5687 expanded without a target. */
5688 if (TREE_CODE (newrhs) == TARGET_EXPR)
5689 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5690 TREE_OPERAND (newrhs, 0));
5693 if (newrhs == error_mark_node)
5694 return error_mark_node;
5696 if (c_dialect_objc () && flag_objc_gc)
5698 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
5704 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5705 lhstype, lhs, newrhs);
5707 TREE_SIDE_EFFECTS (result) = 1;
5709 TREE_NO_WARNING (result) = 1;
5711 /* If we got the LHS in a different type for storing in,
5712 convert the result back to the nominal type of LHS
5713 so that the value we return always has the same type
5714 as the LHS argument. */
5716 if (olhstype == TREE_TYPE (result))
5720 result = build2 (COMPOUND_EXPR, olhstype, result, olhs);
5721 TREE_NO_WARNING (result) = 1;
5724 return convert_for_assignment (olhstype, result, "assignment",
5729 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5731 if (processing_template_decl)
5732 return build_min_nt (MODOP_EXPR, lhs,
5733 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5735 if (modifycode != NOP_EXPR)
5737 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5738 make_node (modifycode),
5739 /*overloaded_p=*/NULL);
5742 TREE_NO_WARNING (rval) = 1;
5746 return build_modify_expr (lhs, modifycode, rhs);
5750 /* Get difference in deltas for different pointer to member function
5751 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5752 the conversion is invalid, the constant is zero. If
5753 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
5754 If C_CAST_P is true this conversion is taking place as part of a
5757 Note that the naming of FROM and TO is kind of backwards; the return
5758 value is what we add to a TO in order to get a FROM. They are named
5759 this way because we call this function to find out how to convert from
5760 a pointer to member of FROM to a pointer to member of TO. */
5763 get_delta_difference (tree from, tree to,
5764 bool allow_inverse_p,
5771 /* Assume no conversion is required. */
5772 result = integer_zero_node;
5773 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
5774 if (kind == bk_inaccessible || kind == bk_ambig)
5775 error (" in pointer to member function conversion");
5778 if (kind != bk_via_virtual)
5779 result = BINFO_OFFSET (binfo);
5782 tree virt_binfo = binfo_from_vbase (binfo);
5784 /* This is a reinterpret cast, we choose to do nothing. */
5785 if (allow_inverse_p)
5786 warning (0, "pointer to member cast via virtual base %qT",
5787 BINFO_TYPE (virt_binfo));
5789 error ("pointer to member conversion via virtual base %qT",
5790 BINFO_TYPE (virt_binfo));
5793 else if (same_type_ignoring_top_level_qualifiers_p (from, to))
5794 /* Pointer to member of incomplete class is permitted*/;
5795 else if (!allow_inverse_p)
5797 error_not_base_type (from, to);
5798 error (" in pointer to member conversion");
5802 binfo = lookup_base (from, to, c_cast_p ? ba_unique : ba_check, &kind);
5805 if (kind != bk_via_virtual)
5806 result = size_diffop (size_zero_node, BINFO_OFFSET (binfo));
5809 /* This is a reinterpret cast, we choose to do nothing. */
5810 tree virt_binfo = binfo_from_vbase (binfo);
5812 warning (0, "pointer to member cast via virtual base %qT",
5813 BINFO_TYPE (virt_binfo));
5818 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
5822 /* Return a constructor for the pointer-to-member-function TYPE using
5823 the other components as specified. */
5826 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5831 VEC(constructor_elt, gc) *v;
5833 /* Pull the FIELD_DECLs out of the type. */
5834 pfn_field = TYPE_FIELDS (type);
5835 delta_field = TREE_CHAIN (pfn_field);
5837 /* Make sure DELTA has the type we want. */
5838 delta = convert_and_check (delta_type_node, delta);
5840 /* Finish creating the initializer. */
5841 v = VEC_alloc(constructor_elt, gc, 2);
5842 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
5843 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
5844 u = build_constructor (type, v);
5845 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
5846 TREE_INVARIANT (u) = TREE_INVARIANT (pfn) & TREE_INVARIANT (delta);
5847 TREE_STATIC (u) = (TREE_CONSTANT (u)
5848 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5850 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5855 /* Build a constructor for a pointer to member function. It can be
5856 used to initialize global variables, local variable, or used
5857 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5860 If FORCE is nonzero, then force this conversion, even if
5861 we would rather not do it. Usually set when using an explicit
5862 cast. A C-style cast is being processed iff C_CAST_P is true.
5864 Return error_mark_node, if something goes wrong. */
5867 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
5873 if (error_operand_p (pfn))
5874 return error_mark_node;
5876 pfn_type = TREE_TYPE (pfn);
5877 to_type = build_ptrmemfunc_type (type);
5879 /* Handle multiple conversions of pointer to member functions. */
5880 if (TYPE_PTRMEMFUNC_P (pfn_type))
5882 tree delta = NULL_TREE;
5883 tree npfn = NULL_TREE;
5887 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
5888 error ("invalid conversion to type %qT from type %qT",
5891 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5892 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5896 /* We don't have to do any conversion to convert a
5897 pointer-to-member to its own type. But, we don't want to
5898 just return a PTRMEM_CST if there's an explicit cast; that
5899 cast should make the expression an invalid template argument. */
5900 if (TREE_CODE (pfn) != PTRMEM_CST)
5902 if (same_type_p (to_type, pfn_type))
5904 else if (integer_zerop (n))
5905 return build_reinterpret_cast (to_type, pfn);
5908 if (TREE_SIDE_EFFECTS (pfn))
5909 pfn = save_expr (pfn);
5911 /* Obtain the function pointer and the current DELTA. */
5912 if (TREE_CODE (pfn) == PTRMEM_CST)
5913 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
5916 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
5917 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
5920 /* Just adjust the DELTA field. */
5921 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5922 (TREE_TYPE (delta), ptrdiff_type_node));
5923 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
5924 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
5925 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
5926 return build_ptrmemfunc1 (to_type, delta, npfn);
5929 /* Handle null pointer to member function conversions. */
5930 if (integer_zerop (pfn))
5932 pfn = build_c_cast (type, integer_zero_node);
5933 return build_ptrmemfunc1 (to_type,
5938 if (type_unknown_p (pfn))
5939 return instantiate_type (type, pfn, tf_warning_or_error);
5941 fn = TREE_OPERAND (pfn, 0);
5942 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
5943 /* In a template, we will have preserved the
5945 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
5946 return make_ptrmem_cst (to_type, fn);
5949 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
5952 ??? There is no consistency as to the types returned for the above
5953 values. Some code acts as if it were a sizetype and some as if it were
5954 integer_type_node. */
5957 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
5959 tree type = TREE_TYPE (cst);
5960 tree fn = PTRMEM_CST_MEMBER (cst);
5961 tree ptr_class, fn_class;
5963 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
5965 /* The class that the function belongs to. */
5966 fn_class = DECL_CONTEXT (fn);
5968 /* The class that we're creating a pointer to member of. */
5969 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
5971 /* First, calculate the adjustment to the function's class. */
5972 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
5975 if (!DECL_VIRTUAL_P (fn))
5976 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
5979 /* If we're dealing with a virtual function, we have to adjust 'this'
5980 again, to point to the base which provides the vtable entry for
5981 fn; the call will do the opposite adjustment. */
5982 tree orig_class = DECL_CONTEXT (fn);
5983 tree binfo = binfo_or_else (orig_class, fn_class);
5984 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
5985 *delta, BINFO_OFFSET (binfo));
5986 *delta = fold_if_not_in_template (*delta);
5988 /* We set PFN to the vtable offset at which the function can be
5989 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
5990 case delta is shifted left, and then incremented). */
5991 *pfn = DECL_VINDEX (fn);
5992 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
5993 TYPE_SIZE_UNIT (vtable_entry_type));
5994 *pfn = fold_if_not_in_template (*pfn);
5996 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
5998 case ptrmemfunc_vbit_in_pfn:
5999 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6001 *pfn = fold_if_not_in_template (*pfn);
6004 case ptrmemfunc_vbit_in_delta:
6005 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6006 *delta, integer_one_node);
6007 *delta = fold_if_not_in_template (*delta);
6008 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6009 *delta, integer_one_node);
6010 *delta = fold_if_not_in_template (*delta);
6017 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6018 *pfn = fold_if_not_in_template (*pfn);
6022 /* Return an expression for PFN from the pointer-to-member function
6026 pfn_from_ptrmemfunc (tree t)
6028 if (TREE_CODE (t) == PTRMEM_CST)
6033 expand_ptrmemfunc_cst (t, &delta, &pfn);
6038 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6041 /* Convert value RHS to type TYPE as preparation for an assignment to
6042 an lvalue of type TYPE. ERRTYPE is a string to use in error
6043 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6044 are doing the conversion in order to pass the PARMNUMth argument of
6048 convert_for_assignment (tree type, tree rhs,
6049 const char *errtype, tree fndecl, int parmnum)
6052 enum tree_code coder;
6054 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6055 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6056 rhs = TREE_OPERAND (rhs, 0);
6058 rhstype = TREE_TYPE (rhs);
6059 coder = TREE_CODE (rhstype);
6061 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6062 && vector_types_convertible_p (type, rhstype))
6063 return convert (type, rhs);
6065 if (rhs == error_mark_node || rhstype == error_mark_node)
6066 return error_mark_node;
6067 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6068 return error_mark_node;
6070 /* The RHS of an assignment cannot have void type. */
6071 if (coder == VOID_TYPE)
6073 error ("void value not ignored as it ought to be");
6074 return error_mark_node;
6077 /* Simplify the RHS if possible. */
6078 if (TREE_CODE (rhs) == CONST_DECL)
6079 rhs = DECL_INITIAL (rhs);
6081 if (c_dialect_objc ())
6084 tree rname = fndecl;
6086 if (!strcmp (errtype, "assignment"))
6088 else if (!strcmp (errtype, "initialization"))
6092 tree selector = objc_message_selector ();
6096 if (selector && parmno > 1)
6103 if (objc_compare_types (type, rhstype, parmno, rname))
6104 return convert (type, rhs);
6109 The expression is implicitly converted (clause _conv_) to the
6110 cv-unqualified type of the left operand.
6112 We allow bad conversions here because by the time we get to this point
6113 we are committed to doing the conversion. If we end up doing a bad
6114 conversion, convert_like will complain. */
6115 if (!can_convert_arg_bad (type, rhstype, rhs))
6117 /* When -Wno-pmf-conversions is use, we just silently allow
6118 conversions from pointers-to-members to plain pointers. If
6119 the conversion doesn't work, cp_convert will complain. */
6121 && TYPE_PTR_P (type)
6122 && TYPE_PTRMEMFUNC_P (rhstype))
6123 rhs = cp_convert (strip_top_quals (type), rhs);
6126 /* If the right-hand side has unknown type, then it is an
6127 overloaded function. Call instantiate_type to get error
6129 if (rhstype == unknown_type_node)
6130 instantiate_type (type, rhs, tf_warning_or_error);
6132 error ("cannot convert %qT to %qT for argument %qP to %qD",
6133 rhstype, type, parmnum, fndecl);
6135 error ("cannot convert %qT to %qT in %s", rhstype, type, errtype);
6136 return error_mark_node;
6139 if (warn_missing_format_attribute)
6141 const enum tree_code codel = TREE_CODE (type);
6142 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6144 && check_missing_format_attribute (type, rhstype))
6145 warning (OPT_Wmissing_format_attribute,
6146 "%s might be a candidate for a format attribute",
6150 return perform_implicit_conversion (strip_top_quals (type), rhs);
6153 /* Convert RHS to be of type TYPE.
6154 If EXP is nonzero, it is the target of the initialization.
6155 ERRTYPE is a string to use in error messages.
6157 Two major differences between the behavior of
6158 `convert_for_assignment' and `convert_for_initialization'
6159 are that references are bashed in the former, while
6160 copied in the latter, and aggregates are assigned in
6161 the former (operator=) while initialized in the
6164 If using constructor make sure no conversion operator exists, if one does
6165 exist, an ambiguity exists.
6167 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6170 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6171 const char *errtype, tree fndecl, int parmnum)
6173 enum tree_code codel = TREE_CODE (type);
6175 enum tree_code coder;
6177 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6178 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6179 if (TREE_CODE (rhs) == NOP_EXPR
6180 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6181 && codel != REFERENCE_TYPE)
6182 rhs = TREE_OPERAND (rhs, 0);
6184 if (rhs == error_mark_node
6185 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6186 return error_mark_node;
6188 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6189 && TREE_CODE (type) != ARRAY_TYPE
6190 && (TREE_CODE (type) != REFERENCE_TYPE
6191 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6192 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6193 && (TREE_CODE (type) != REFERENCE_TYPE
6194 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6195 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6196 rhs = decay_conversion (rhs);
6198 rhstype = TREE_TYPE (rhs);
6199 coder = TREE_CODE (rhstype);
6201 if (coder == ERROR_MARK)
6202 return error_mark_node;
6204 /* We accept references to incomplete types, so we can
6205 return here before checking if RHS is of complete type. */
6207 if (codel == REFERENCE_TYPE)
6209 /* This should eventually happen in convert_arguments. */
6210 int savew = 0, savee = 0;
6213 savew = warningcount, savee = errorcount;
6214 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6218 if (warningcount > savew)
6219 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6220 else if (errorcount > savee)
6221 error ("in passing argument %P of %q+D", parmnum, fndecl);
6227 exp = require_complete_type (exp);
6228 if (exp == error_mark_node)
6229 return error_mark_node;
6231 rhstype = non_reference (rhstype);
6233 type = complete_type (type);
6235 if (IS_AGGR_TYPE (type))
6236 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6238 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
6241 /* If RETVAL is the address of, or a reference to, a local variable or
6242 temporary give an appropriate warning. */
6245 maybe_warn_about_returning_address_of_local (tree retval)
6247 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6248 tree whats_returned = retval;
6252 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6253 whats_returned = TREE_OPERAND (whats_returned, 1);
6254 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
6255 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
6256 || TREE_CODE (whats_returned) == NOP_EXPR)
6257 whats_returned = TREE_OPERAND (whats_returned, 0);
6262 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6264 whats_returned = TREE_OPERAND (whats_returned, 0);
6266 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6268 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6269 || TREE_CODE (whats_returned) == TARGET_EXPR)
6271 warning (0, "returning reference to temporary");
6274 if (TREE_CODE (whats_returned) == VAR_DECL
6275 && DECL_NAME (whats_returned)
6276 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6278 warning (0, "reference to non-lvalue returned");
6283 if (DECL_P (whats_returned)
6284 && DECL_NAME (whats_returned)
6285 && DECL_FUNCTION_SCOPE_P (whats_returned)
6286 && !(TREE_STATIC (whats_returned)
6287 || TREE_PUBLIC (whats_returned)))
6289 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6290 warning (0, "reference to local variable %q+D returned",
6293 warning (0, "address of local variable %q+D returned",
6299 /* Check that returning RETVAL from the current function is valid.
6300 Return an expression explicitly showing all conversions required to
6301 change RETVAL into the function return type, and to assign it to
6302 the DECL_RESULT for the function. Set *NO_WARNING to true if
6303 code reaches end of non-void function warning shouldn't be issued
6304 on this RETURN_EXPR. */
6307 check_return_expr (tree retval, bool *no_warning)
6310 /* The type actually returned by the function, after any
6313 int fn_returns_value_p;
6315 *no_warning = false;
6317 /* A `volatile' function is one that isn't supposed to return, ever.
6318 (This is a G++ extension, used to get better code for functions
6319 that call the `volatile' function.) */
6320 if (TREE_THIS_VOLATILE (current_function_decl))
6321 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6323 /* Check for various simple errors. */
6324 if (DECL_DESTRUCTOR_P (current_function_decl))
6327 error ("returning a value from a destructor");
6330 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6332 if (in_function_try_handler)
6333 /* If a return statement appears in a handler of the
6334 function-try-block of a constructor, the program is ill-formed. */
6335 error ("cannot return from a handler of a function-try-block of a constructor");
6337 /* You can't return a value from a constructor. */
6338 error ("returning a value from a constructor");
6342 if (processing_template_decl)
6344 current_function_returns_value = 1;
6348 /* When no explicit return-value is given in a function with a named
6349 return value, the named return value is used. */
6350 result = DECL_RESULT (current_function_decl);
6351 valtype = TREE_TYPE (result);
6352 gcc_assert (valtype != NULL_TREE);
6353 fn_returns_value_p = !VOID_TYPE_P (valtype);
6354 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6357 /* Check for a return statement with no return value in a function
6358 that's supposed to return a value. */
6359 if (!retval && fn_returns_value_p)
6361 pedwarn ("return-statement with no value, in function returning %qT",
6363 /* Clear this, so finish_function won't say that we reach the
6364 end of a non-void function (which we don't, we gave a
6366 current_function_returns_null = 0;
6367 /* And signal caller that TREE_NO_WARNING should be set on the
6368 RETURN_EXPR to avoid control reaches end of non-void function
6369 warnings in tree-cfg.c. */
6372 /* Check for a return statement with a value in a function that
6373 isn't supposed to return a value. */
6374 else if (retval && !fn_returns_value_p)
6376 if (VOID_TYPE_P (TREE_TYPE (retval)))
6377 /* You can return a `void' value from a function of `void'
6378 type. In that case, we have to evaluate the expression for
6379 its side-effects. */
6380 finish_expr_stmt (retval);
6382 pedwarn ("return-statement with a value, in function "
6383 "returning 'void'");
6385 current_function_returns_null = 1;
6387 /* There's really no value to return, after all. */
6391 /* Remember that this function can sometimes return without a
6393 current_function_returns_null = 1;
6395 /* Remember that this function did return a value. */
6396 current_function_returns_value = 1;
6398 /* Check for erroneous operands -- but after giving ourselves a
6399 chance to provide an error about returning a value from a void
6401 if (error_operand_p (retval))
6403 current_function_return_value = error_mark_node;
6404 return error_mark_node;
6407 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
6408 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
6409 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
6410 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
6412 && null_ptr_cst_p (retval))
6413 warning (0, "%<operator new%> must not return NULL unless it is "
6414 "declared %<throw()%> (or -fcheck-new is in effect)");
6416 /* Effective C++ rule 15. See also start_function. */
6418 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
6422 /* The function return type must be a reference to the current
6424 if (TREE_CODE (valtype) == REFERENCE_TYPE
6425 && same_type_ignoring_top_level_qualifiers_p
6426 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
6428 /* Returning '*this' is obviously OK. */
6429 if (retval == current_class_ref)
6431 /* If we are calling a function whose return type is the same of
6432 the current class reference, it is ok. */
6433 else if (TREE_CODE (retval) == INDIRECT_REF
6434 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
6439 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
6442 /* The fabled Named Return Value optimization, as per [class.copy]/15:
6444 [...] For a function with a class return type, if the expression
6445 in the return statement is the name of a local object, and the cv-
6446 unqualified type of the local object is the same as the function
6447 return type, an implementation is permitted to omit creating the tem-
6448 porary object to hold the function return value [...]
6450 So, if this is a value-returning function that always returns the same
6451 local variable, remember it.
6453 It might be nice to be more flexible, and choose the first suitable
6454 variable even if the function sometimes returns something else, but
6455 then we run the risk of clobbering the variable we chose if the other
6456 returned expression uses the chosen variable somehow. And people expect
6457 this restriction, anyway. (jason 2000-11-19)
6459 See finish_function and finalize_nrv for the rest of this optimization. */
6461 if (fn_returns_value_p && flag_elide_constructors)
6463 if (retval != NULL_TREE
6464 && (current_function_return_value == NULL_TREE
6465 || current_function_return_value == retval)
6466 && TREE_CODE (retval) == VAR_DECL
6467 && DECL_CONTEXT (retval) == current_function_decl
6468 && ! TREE_STATIC (retval)
6469 && (DECL_ALIGN (retval)
6470 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6471 && same_type_p ((TYPE_MAIN_VARIANT
6472 (TREE_TYPE (retval))),
6474 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
6475 current_function_return_value = retval;
6477 current_function_return_value = error_mark_node;
6480 /* We don't need to do any conversions when there's nothing being
6485 /* Do any required conversions. */
6486 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6487 /* No conversions are required. */
6491 /* The type the function is declared to return. */
6492 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6494 /* The functype's return type will have been set to void, if it
6495 was an incomplete type. Just treat this as 'return;' */
6496 if (VOID_TYPE_P (functype))
6497 return error_mark_node;
6499 /* First convert the value to the function's return type, then
6500 to the type of return value's location to handle the
6501 case that functype is smaller than the valtype. */
6502 retval = convert_for_initialization
6503 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
6504 "return", NULL_TREE, 0);
6505 retval = convert (valtype, retval);
6507 /* If the conversion failed, treat this just like `return;'. */
6508 if (retval == error_mark_node)
6510 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6511 else if (! current_function_returns_struct
6512 && TREE_CODE (retval) == TARGET_EXPR
6513 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6514 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6515 TREE_OPERAND (retval, 0));
6517 maybe_warn_about_returning_address_of_local (retval);
6520 /* Actually copy the value returned into the appropriate location. */
6521 if (retval && retval != result)
6522 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
6528 /* Returns nonzero if the pointer-type FROM can be converted to the
6529 pointer-type TO via a qualification conversion. If CONSTP is -1,
6530 then we return nonzero if the pointers are similar, and the
6531 cv-qualification signature of FROM is a proper subset of that of TO.
6533 If CONSTP is positive, then all outer pointers have been
6537 comp_ptr_ttypes_real (tree to, tree from, int constp)
6539 bool to_more_cv_qualified = false;
6541 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6543 if (TREE_CODE (to) != TREE_CODE (from))
6546 if (TREE_CODE (from) == OFFSET_TYPE
6547 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
6548 TYPE_OFFSET_BASETYPE (to)))
6551 /* Const and volatile mean something different for function types,
6552 so the usual checks are not appropriate. */
6553 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6555 /* In Objective-C++, some types may have been 'volatilized' by
6556 the compiler for EH; when comparing them here, the volatile
6557 qualification must be ignored. */
6558 bool objc_quals_match = objc_type_quals_match (to, from);
6560 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
6563 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
6567 to_more_cv_qualified = true;
6571 constp &= TYPE_READONLY (to);
6574 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
6575 return ((constp >= 0 || to_more_cv_qualified)
6576 && same_type_ignoring_top_level_qualifiers_p (to, from));
6580 /* When comparing, say, char ** to char const **, this function takes
6581 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6582 types to this function. */
6585 comp_ptr_ttypes (tree to, tree from)
6587 return comp_ptr_ttypes_real (to, from, 1);
6590 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6591 type or inheritance-related types, regardless of cv-quals. */
6594 ptr_reasonably_similar (tree to, tree from)
6596 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6598 /* Any target type is similar enough to void. */
6599 if (TREE_CODE (to) == VOID_TYPE
6600 || TREE_CODE (from) == VOID_TYPE)
6603 if (TREE_CODE (to) != TREE_CODE (from))
6606 if (TREE_CODE (from) == OFFSET_TYPE
6607 && comptypes (TYPE_OFFSET_BASETYPE (to),
6608 TYPE_OFFSET_BASETYPE (from),
6609 COMPARE_BASE | COMPARE_DERIVED))
6612 if (TREE_CODE (to) == VECTOR_TYPE
6613 && vector_types_convertible_p (to, from))
6616 if (TREE_CODE (to) == INTEGER_TYPE
6617 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6620 if (TREE_CODE (to) == FUNCTION_TYPE)
6623 if (TREE_CODE (to) != POINTER_TYPE)
6625 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6626 COMPARE_BASE | COMPARE_DERIVED);
6630 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
6631 pointer-to-member types) are the same, ignoring cv-qualification at
6635 comp_ptr_ttypes_const (tree to, tree from)
6637 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6639 if (TREE_CODE (to) != TREE_CODE (from))
6642 if (TREE_CODE (from) == OFFSET_TYPE
6643 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6644 TYPE_OFFSET_BASETYPE (to)))
6647 if (TREE_CODE (to) != POINTER_TYPE)
6648 return same_type_ignoring_top_level_qualifiers_p (to, from);
6652 /* Returns the type qualifiers for this type, including the qualifiers on the
6653 elements for an array type. */
6656 cp_type_quals (tree type)
6658 type = strip_array_types (type);
6659 if (type == error_mark_node)
6660 return TYPE_UNQUALIFIED;
6661 return TYPE_QUALS (type);
6664 /* Returns nonzero if the TYPE contains a mutable member. */
6667 cp_has_mutable_p (tree type)
6669 type = strip_array_types (type);
6671 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6674 /* Apply the TYPE_QUALS to the new DECL. */
6676 cp_apply_type_quals_to_decl (int type_quals, tree decl)
6678 tree type = TREE_TYPE (decl);
6680 if (type == error_mark_node)
6683 if (TREE_CODE (type) == FUNCTION_TYPE
6684 && type_quals != TYPE_UNQUALIFIED)
6686 /* This was an error in C++98 (cv-qualifiers cannot be added to
6687 a function type), but DR 295 makes the code well-formed by
6688 dropping the extra qualifiers. */
6691 tree bad_type = build_qualified_type (type, type_quals);
6692 pedwarn ("ignoring %qV qualifiers added to function type %qT",
6696 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
6700 /* Avoid setting TREE_READONLY incorrectly. */
6701 if (/* If the object has a constructor, the constructor may modify
6703 TYPE_NEEDS_CONSTRUCTING (type)
6704 /* If the type isn't complete, we don't know yet if it will need
6706 || !COMPLETE_TYPE_P (type)
6707 /* If the type has a mutable component, that component might be
6709 || TYPE_HAS_MUTABLE_P (type))
6710 type_quals &= ~TYPE_QUAL_CONST;
6712 c_apply_type_quals_to_decl (type_quals, decl);
6715 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6716 exemplar types such that casting T1 to T2 is casting away constness
6717 if and only if there is no implicit conversion from T1 to T2. */
6720 casts_away_constness_r (tree *t1, tree *t2)
6725 /* [expr.const.cast]
6727 For multi-level pointer to members and multi-level mixed pointers
6728 and pointers to members (conv.qual), the "member" aspect of a
6729 pointer to member level is ignored when determining if a const
6730 cv-qualifier has been cast away. */
6731 /* [expr.const.cast]
6733 For two pointer types:
6735 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6736 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6739 casting from X1 to X2 casts away constness if, for a non-pointer
6740 type T there does not exist an implicit conversion (clause
6743 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6747 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6748 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
6749 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
6751 *t1 = cp_build_qualified_type (void_type_node,
6752 cp_type_quals (*t1));
6753 *t2 = cp_build_qualified_type (void_type_node,
6754 cp_type_quals (*t2));
6758 quals1 = cp_type_quals (*t1);
6759 quals2 = cp_type_quals (*t2);
6761 if (TYPE_PTRMEM_P (*t1))
6762 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
6764 *t1 = TREE_TYPE (*t1);
6765 if (TYPE_PTRMEM_P (*t2))
6766 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
6768 *t2 = TREE_TYPE (*t2);
6770 casts_away_constness_r (t1, t2);
6771 *t1 = build_pointer_type (*t1);
6772 *t2 = build_pointer_type (*t2);
6773 *t1 = cp_build_qualified_type (*t1, quals1);
6774 *t2 = cp_build_qualified_type (*t2, quals2);
6777 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6781 casts_away_constness (tree t1, tree t2)
6783 if (TREE_CODE (t2) == REFERENCE_TYPE)
6785 /* [expr.const.cast]
6787 Casting from an lvalue of type T1 to an lvalue of type T2
6788 using a reference cast casts away constness if a cast from an
6789 rvalue of type "pointer to T1" to the type "pointer to T2"
6790 casts away constness. */
6791 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6792 return casts_away_constness (build_pointer_type (t1),
6793 build_pointer_type (TREE_TYPE (t2)));
6796 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6797 /* [expr.const.cast]
6799 Casting from an rvalue of type "pointer to data member of X
6800 of type T1" to the type "pointer to data member of Y of type
6801 T2" casts away constness if a cast from an rvalue of type
6802 "pointer to T1" to the type "pointer to T2" casts away
6804 return casts_away_constness
6805 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6806 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6808 /* Casting away constness is only something that makes sense for
6809 pointer or reference types. */
6810 if (TREE_CODE (t1) != POINTER_TYPE
6811 || TREE_CODE (t2) != POINTER_TYPE)
6814 /* Top-level qualifiers don't matter. */
6815 t1 = TYPE_MAIN_VARIANT (t1);
6816 t2 = TYPE_MAIN_VARIANT (t2);
6817 casts_away_constness_r (&t1, &t2);
6818 if (!can_convert (t2, t1))
6824 /* If T is a REFERENCE_TYPE return the type to which T refers.
6825 Otherwise, return T itself. */
6828 non_reference (tree t)
6830 if (TREE_CODE (t) == REFERENCE_TYPE)
6836 /* Return nonzero if REF is an lvalue valid for this language;
6837 otherwise, print an error message and return zero. USE says
6838 how the lvalue is being used and so selects the error message. */
6841 lvalue_or_else (tree ref, enum lvalue_use use)
6843 int win = lvalue_p (ref);