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 /* If EXP is a reference to a bitfield, and the type of EXP does not
1402 match the declared type of the bitfield, return the declared type
1403 of the bitfield. Otherwise, return NULL_TREE. */
1406 is_bitfield_expr_with_lowered_type (tree exp)
1410 if (TREE_CODE (exp) == COND_EXPR)
1412 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)))
1414 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2));
1416 if (TREE_CODE (exp) != COMPONENT_REF)
1418 field = TREE_OPERAND (exp, 1);
1419 if (TREE_CODE (field) != FIELD_DECL || !DECL_C_BIT_FIELD (field))
1421 if (same_type_ignoring_top_level_qualifiers_p
1422 (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field)))
1424 return DECL_BIT_FIELD_TYPE (field);
1427 /* Perform the conversions in [expr] that apply when an lvalue appears
1428 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1429 function-to-pointer conversions.
1431 In addition, manifest constants are replaced by their values, and
1432 bitfield references are converted to their declared types. */
1435 decay_conversion (tree exp)
1438 enum tree_code code;
1440 type = TREE_TYPE (exp);
1441 if (type == error_mark_node)
1442 return error_mark_node;
1444 if (type_unknown_p (exp))
1446 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1447 return error_mark_node;
1450 exp = decl_constant_value (exp);
1452 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1453 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1454 code = TREE_CODE (type);
1455 if (code == VOID_TYPE)
1457 error ("void value not ignored as it ought to be");
1458 return error_mark_node;
1460 if (invalid_nonstatic_memfn_p (exp))
1461 return error_mark_node;
1462 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1463 return build_unary_op (ADDR_EXPR, exp, 0);
1464 if (code == ARRAY_TYPE)
1469 if (TREE_CODE (exp) == INDIRECT_REF)
1470 return build_nop (build_pointer_type (TREE_TYPE (type)),
1471 TREE_OPERAND (exp, 0));
1473 if (TREE_CODE (exp) == COMPOUND_EXPR)
1475 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1476 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1477 TREE_OPERAND (exp, 0), op1);
1481 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1483 error ("invalid use of non-lvalue array");
1484 return error_mark_node;
1487 ptrtype = build_pointer_type (TREE_TYPE (type));
1489 if (TREE_CODE (exp) == VAR_DECL)
1491 if (!cxx_mark_addressable (exp))
1492 return error_mark_node;
1493 adr = build_nop (ptrtype, build_address (exp));
1496 /* This way is better for a COMPONENT_REF since it can
1497 simplify the offset for a component. */
1498 adr = build_unary_op (ADDR_EXPR, exp, 1);
1499 return cp_convert (ptrtype, adr);
1502 /* [basic.lval]: Class rvalues can have cv-qualified types; non-class
1503 rvalues always have cv-unqualified types. */
1504 if (! CLASS_TYPE_P (type))
1505 exp = cp_convert (TYPE_MAIN_VARIANT (type), exp);
1511 default_conversion (tree exp)
1513 exp = decay_conversion (exp);
1515 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1516 exp = perform_integral_promotions (exp);
1521 /* EXPR is an expression with an integral or enumeration type.
1522 Perform the integral promotions in [conv.prom], and return the
1526 perform_integral_promotions (tree expr)
1533 If the bitfield has an enumerated type, it is treated as any
1534 other value of that type for promotion purposes. */
1535 type = is_bitfield_expr_with_lowered_type (expr);
1536 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
1537 type = TREE_TYPE (expr);
1538 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1539 promoted_type = type_promotes_to (type);
1540 if (type != promoted_type)
1541 expr = cp_convert (promoted_type, expr);
1545 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1549 inline_conversion (tree exp)
1551 if (TREE_CODE (exp) == FUNCTION_DECL)
1552 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1557 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1558 decay_conversion to one. */
1561 string_conv_p (tree totype, tree exp, int warn)
1565 if (TREE_CODE (totype) != POINTER_TYPE)
1568 t = TREE_TYPE (totype);
1569 if (!same_type_p (t, char_type_node)
1570 && !same_type_p (t, wchar_type_node))
1573 if (TREE_CODE (exp) == STRING_CST)
1575 /* Make sure that we don't try to convert between char and wchar_t. */
1576 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1581 /* Is this a string constant which has decayed to 'const char *'? */
1582 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1583 if (!same_type_p (TREE_TYPE (exp), t))
1586 if (TREE_CODE (exp) != ADDR_EXPR
1587 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1591 /* This warning is not very useful, as it complains about printf. */
1593 warning (OPT_Wwrite_strings, "deprecated conversion from string constant to %qT'", totype);
1598 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1599 can, for example, use as an lvalue. This code used to be in
1600 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1601 expressions, where we're dealing with aggregates. But now it's again only
1602 called from unary_complex_lvalue. The case (in particular) that led to
1603 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1607 rationalize_conditional_expr (enum tree_code code, tree t)
1609 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1610 the first operand is always the one to be used if both operands
1611 are equal, so we know what conditional expression this used to be. */
1612 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1614 /* The following code is incorrect if either operand side-effects. */
1615 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0))
1616 && !TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)));
1618 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1619 ? LE_EXPR : GE_EXPR),
1620 TREE_OPERAND (t, 0),
1621 TREE_OPERAND (t, 1),
1622 /*overloaded_p=*/NULL),
1623 build_unary_op (code, TREE_OPERAND (t, 0), 0),
1624 build_unary_op (code, TREE_OPERAND (t, 1), 0));
1628 build_conditional_expr (TREE_OPERAND (t, 0),
1629 build_unary_op (code, TREE_OPERAND (t, 1), 0),
1630 build_unary_op (code, TREE_OPERAND (t, 2), 0));
1633 /* Given the TYPE of an anonymous union field inside T, return the
1634 FIELD_DECL for the field. If not found return NULL_TREE. Because
1635 anonymous unions can nest, we must also search all anonymous unions
1636 that are directly reachable. */
1639 lookup_anon_field (tree t, tree type)
1643 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1645 if (TREE_STATIC (field))
1647 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1650 /* If we find it directly, return the field. */
1651 if (DECL_NAME (field) == NULL_TREE
1652 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1657 /* Otherwise, it could be nested, search harder. */
1658 if (DECL_NAME (field) == NULL_TREE
1659 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1661 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1669 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1670 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1671 non-NULL, it indicates the path to the base used to name MEMBER.
1672 If PRESERVE_REFERENCE is true, the expression returned will have
1673 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1674 returned will have the type referred to by the reference.
1676 This function does not perform access control; that is either done
1677 earlier by the parser when the name of MEMBER is resolved to MEMBER
1678 itself, or later when overload resolution selects one of the
1679 functions indicated by MEMBER. */
1682 build_class_member_access_expr (tree object, tree member,
1683 tree access_path, bool preserve_reference)
1687 tree result = NULL_TREE;
1689 if (object == error_mark_node || member == error_mark_node)
1690 return error_mark_node;
1692 gcc_assert (DECL_P (member) || BASELINK_P (member));
1696 The type of the first expression shall be "class object" (of a
1698 object_type = TREE_TYPE (object);
1699 if (!currently_open_class (object_type)
1700 && !complete_type_or_else (object_type, object))
1701 return error_mark_node;
1702 if (!CLASS_TYPE_P (object_type))
1704 error ("request for member %qD in %qE, which is of non-class type %qT",
1705 member, object, object_type);
1706 return error_mark_node;
1709 /* The standard does not seem to actually say that MEMBER must be a
1710 member of OBJECT_TYPE. However, that is clearly what is
1712 if (DECL_P (member))
1714 member_scope = DECL_CLASS_CONTEXT (member);
1716 if (TREE_DEPRECATED (member))
1717 warn_deprecated_use (member);
1720 member_scope = BINFO_TYPE (BASELINK_BINFO (member));
1721 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1722 presently be the anonymous union. Go outwards until we find a
1723 type related to OBJECT_TYPE. */
1724 while (ANON_AGGR_TYPE_P (member_scope)
1725 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1727 member_scope = TYPE_CONTEXT (member_scope);
1728 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1730 if (TREE_CODE (member) == FIELD_DECL)
1731 error ("invalid use of nonstatic data member %qE", member);
1733 error ("%qD is not a member of %qT", member, object_type);
1734 return error_mark_node;
1737 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1738 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1739 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1741 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1743 object = build_indirect_ref (temp, NULL);
1746 /* In [expr.ref], there is an explicit list of the valid choices for
1747 MEMBER. We check for each of those cases here. */
1748 if (TREE_CODE (member) == VAR_DECL)
1750 /* A static data member. */
1752 /* If OBJECT has side-effects, they are supposed to occur. */
1753 if (TREE_SIDE_EFFECTS (object))
1754 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1756 else if (TREE_CODE (member) == FIELD_DECL)
1758 /* A non-static data member. */
1763 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1764 && integer_zerop (TREE_OPERAND (object, 0)));
1766 /* Convert OBJECT to the type of MEMBER. */
1767 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1768 TYPE_MAIN_VARIANT (member_scope)))
1773 binfo = lookup_base (access_path ? access_path : object_type,
1774 member_scope, ba_unique, &kind);
1775 if (binfo == error_mark_node)
1776 return error_mark_node;
1778 /* It is invalid to try to get to a virtual base of a
1779 NULL object. The most common cause is invalid use of
1781 if (null_object_p && kind == bk_via_virtual)
1783 error ("invalid access to non-static data member %qD of "
1786 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
1787 return error_mark_node;
1790 /* Convert to the base. */
1791 object = build_base_path (PLUS_EXPR, object, binfo,
1793 /* If we found the base successfully then we should be able
1794 to convert to it successfully. */
1795 gcc_assert (object != error_mark_node);
1798 /* Complain about other invalid uses of offsetof, even though they will
1799 give the right answer. Note that we complain whether or not they
1800 actually used the offsetof macro, since there's no way to know at this
1801 point. So we just give a warning, instead of a pedwarn. */
1802 /* Do not produce this warning for base class field references, because
1803 we know for a fact that didn't come from offsetof. This does occur
1804 in various testsuite cases where a null object is passed where a
1805 vtable access is required. */
1806 if (null_object_p && warn_invalid_offsetof
1807 && CLASSTYPE_NON_POD_P (object_type)
1808 && !DECL_FIELD_IS_BASE (member)
1809 && !skip_evaluation)
1811 warning (0, "invalid access to non-static data member %qD of NULL object",
1813 warning (0, "(perhaps the %<offsetof%> macro was used incorrectly)");
1816 /* If MEMBER is from an anonymous aggregate, we have converted
1817 OBJECT so that it refers to the class containing the
1818 anonymous union. Generate a reference to the anonymous union
1819 itself, and recur to find MEMBER. */
1820 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
1821 /* When this code is called from build_field_call, the
1822 object already has the type of the anonymous union.
1823 That is because the COMPONENT_REF was already
1824 constructed, and was then disassembled before calling
1825 build_field_call. After the function-call code is
1826 cleaned up, this waste can be eliminated. */
1827 && (!same_type_ignoring_top_level_qualifiers_p
1828 (TREE_TYPE (object), DECL_CONTEXT (member))))
1830 tree anonymous_union;
1832 anonymous_union = lookup_anon_field (TREE_TYPE (object),
1833 DECL_CONTEXT (member));
1834 object = build_class_member_access_expr (object,
1836 /*access_path=*/NULL_TREE,
1837 preserve_reference);
1840 /* Compute the type of the field, as described in [expr.ref]. */
1841 type_quals = TYPE_UNQUALIFIED;
1842 member_type = TREE_TYPE (member);
1843 if (TREE_CODE (member_type) != REFERENCE_TYPE)
1845 type_quals = (cp_type_quals (member_type)
1846 | cp_type_quals (object_type));
1848 /* A field is const (volatile) if the enclosing object, or the
1849 field itself, is const (volatile). But, a mutable field is
1850 not const, even within a const object. */
1851 if (DECL_MUTABLE_P (member))
1852 type_quals &= ~TYPE_QUAL_CONST;
1853 member_type = cp_build_qualified_type (member_type, type_quals);
1856 result = build3 (COMPONENT_REF, member_type, object, member,
1858 result = fold_if_not_in_template (result);
1860 /* Mark the expression const or volatile, as appropriate. Even
1861 though we've dealt with the type above, we still have to mark the
1862 expression itself. */
1863 if (type_quals & TYPE_QUAL_CONST)
1864 TREE_READONLY (result) = 1;
1865 if (type_quals & TYPE_QUAL_VOLATILE)
1866 TREE_THIS_VOLATILE (result) = 1;
1868 else if (BASELINK_P (member))
1870 /* The member is a (possibly overloaded) member function. */
1874 /* If the MEMBER is exactly one static member function, then we
1875 know the type of the expression. Otherwise, we must wait
1876 until overload resolution has been performed. */
1877 functions = BASELINK_FUNCTIONS (member);
1878 if (TREE_CODE (functions) == FUNCTION_DECL
1879 && DECL_STATIC_FUNCTION_P (functions))
1880 type = TREE_TYPE (functions);
1882 type = unknown_type_node;
1883 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1884 base. That will happen when the function is called. */
1885 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
1887 else if (TREE_CODE (member) == CONST_DECL)
1889 /* The member is an enumerator. */
1891 /* If OBJECT has side-effects, they are supposed to occur. */
1892 if (TREE_SIDE_EFFECTS (object))
1893 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
1898 error ("invalid use of %qD", member);
1899 return error_mark_node;
1902 if (!preserve_reference)
1905 If E2 is declared to have type "reference to T", then ... the
1906 type of E1.E2 is T. */
1907 result = convert_from_reference (result);
1912 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1913 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1916 lookup_destructor (tree object, tree scope, tree dtor_name)
1918 tree object_type = TREE_TYPE (object);
1919 tree dtor_type = TREE_OPERAND (dtor_name, 0);
1922 if (scope && !check_dtor_name (scope, dtor_type))
1924 error ("qualified type %qT does not match destructor name ~%qT",
1926 return error_mark_node;
1928 if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
1930 error ("the type being destroyed is %qT, but the destructor refers to %qT",
1931 TYPE_MAIN_VARIANT (object_type), dtor_type);
1932 return error_mark_node;
1934 expr = lookup_member (dtor_type, complete_dtor_identifier,
1935 /*protect=*/1, /*want_type=*/false);
1936 expr = (adjust_result_of_qualified_name_lookup
1937 (expr, dtor_type, object_type));
1941 /* An expression of the form "A::template B" has been resolved to
1942 DECL. Issue a diagnostic if B is not a template or template
1946 check_template_keyword (tree decl)
1948 /* The standard says:
1952 If a name prefixed by the keyword template is not a member
1953 template, the program is ill-formed.
1955 DR 228 removed the restriction that the template be a member
1958 DR 96, if accepted would add the further restriction that explicit
1959 template arguments must be provided if the template keyword is
1960 used, but, as of 2005-10-16, that DR is still in "drafting". If
1961 this DR is accepted, then the semantic checks here can be
1962 simplified, as the entity named must in fact be a template
1963 specialization, rather than, as at present, a set of overloaded
1964 functions containing at least one template function. */
1965 if (TREE_CODE (decl) != TEMPLATE_DECL
1966 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
1968 if (!is_overloaded_fn (decl))
1969 pedwarn ("%qD is not a template", decl);
1974 if (BASELINK_P (fns))
1975 fns = BASELINK_FUNCTIONS (fns);
1978 tree fn = OVL_CURRENT (fns);
1979 if (TREE_CODE (fn) == TEMPLATE_DECL
1980 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
1982 if (TREE_CODE (fn) == FUNCTION_DECL
1983 && DECL_USE_TEMPLATE (fn)
1984 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
1986 fns = OVL_NEXT (fns);
1989 pedwarn ("%qD is not a template", decl);
1994 /* This function is called by the parser to process a class member
1995 access expression of the form OBJECT.NAME. NAME is a node used by
1996 the parser to represent a name; it is not yet a DECL. It may,
1997 however, be a BASELINK where the BASELINK_FUNCTIONS is a
1998 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
1999 there is no reason to do the lookup twice, so the parser keeps the
2000 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2001 be a template via the use of the "A::template B" syntax. */
2004 finish_class_member_access_expr (tree object, tree name, bool template_p)
2009 tree access_path = NULL_TREE;
2010 tree orig_object = object;
2011 tree orig_name = name;
2013 if (object == error_mark_node || name == error_mark_node)
2014 return error_mark_node;
2016 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2017 if (!objc_is_public (object, name))
2018 return error_mark_node;
2020 object_type = TREE_TYPE (object);
2022 if (processing_template_decl)
2024 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2025 dependent_type_p (object_type)
2026 /* If NAME is just an IDENTIFIER_NODE, then the expression
2028 || TREE_CODE (object) == IDENTIFIER_NODE
2029 /* If NAME is "f<args>", where either 'f' or 'args' is
2030 dependent, then the expression is dependent. */
2031 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2032 && dependent_template_id_p (TREE_OPERAND (name, 0),
2033 TREE_OPERAND (name, 1)))
2034 /* If NAME is "T::X" where "T" is dependent, then the
2035 expression is dependent. */
2036 || (TREE_CODE (name) == SCOPE_REF
2037 && TYPE_P (TREE_OPERAND (name, 0))
2038 && dependent_type_p (TREE_OPERAND (name, 0))))
2039 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2040 object = build_non_dependent_expr (object);
2045 The type of the first expression shall be "class object" (of a
2047 if (!currently_open_class (object_type)
2048 && !complete_type_or_else (object_type, object))
2049 return error_mark_node;
2050 if (!CLASS_TYPE_P (object_type))
2052 error ("request for member %qD in %qE, which is of non-class type %qT",
2053 name, object, object_type);
2054 return error_mark_node;
2057 if (BASELINK_P (name))
2058 /* A member function that has already been looked up. */
2062 bool is_template_id = false;
2063 tree template_args = NULL_TREE;
2066 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2068 is_template_id = true;
2069 template_args = TREE_OPERAND (name, 1);
2070 name = TREE_OPERAND (name, 0);
2072 if (TREE_CODE (name) == OVERLOAD)
2073 name = DECL_NAME (get_first_fn (name));
2074 else if (DECL_P (name))
2075 name = DECL_NAME (name);
2078 if (TREE_CODE (name) == SCOPE_REF)
2080 /* A qualified name. The qualifying class or namespace `S'
2081 has already been looked up; it is either a TYPE or a
2083 scope = TREE_OPERAND (name, 0);
2084 name = TREE_OPERAND (name, 1);
2086 /* If SCOPE is a namespace, then the qualified name does not
2087 name a member of OBJECT_TYPE. */
2088 if (TREE_CODE (scope) == NAMESPACE_DECL)
2090 error ("%<%D::%D%> is not a member of %qT",
2091 scope, name, object_type);
2092 return error_mark_node;
2095 gcc_assert (CLASS_TYPE_P (scope));
2096 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2097 || TREE_CODE (name) == BIT_NOT_EXPR);
2099 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2100 access_path = lookup_base (object_type, scope, ba_check, NULL);
2101 if (access_path == error_mark_node)
2102 return error_mark_node;
2105 error ("%qT is not a base of %qT", scope, object_type);
2106 return error_mark_node;
2112 access_path = object_type;
2115 if (TREE_CODE (name) == BIT_NOT_EXPR)
2116 member = lookup_destructor (object, scope, name);
2119 /* Look up the member. */
2120 member = lookup_member (access_path, name, /*protect=*/1,
2121 /*want_type=*/false);
2122 if (member == NULL_TREE)
2124 error ("%qD has no member named %qE", object_type, name);
2125 return error_mark_node;
2127 if (member == error_mark_node)
2128 return error_mark_node;
2133 tree template = member;
2135 if (BASELINK_P (template))
2136 template = lookup_template_function (template, template_args);
2139 error ("%qD is not a member template function", name);
2140 return error_mark_node;
2145 if (TREE_DEPRECATED (member))
2146 warn_deprecated_use (member);
2149 check_template_keyword (member);
2151 expr = build_class_member_access_expr (object, member, access_path,
2152 /*preserve_reference=*/false);
2153 if (processing_template_decl && expr != error_mark_node)
2155 if (BASELINK_P (member))
2157 if (TREE_CODE (orig_name) == SCOPE_REF)
2158 BASELINK_QUALIFIED_P (member) = 1;
2161 return build_min_non_dep (COMPONENT_REF, expr,
2162 orig_object, orig_name,
2169 /* Return an expression for the MEMBER_NAME field in the internal
2170 representation of PTRMEM, a pointer-to-member function. (Each
2171 pointer-to-member function type gets its own RECORD_TYPE so it is
2172 more convenient to access the fields by name than by FIELD_DECL.)
2173 This routine converts the NAME to a FIELD_DECL and then creates the
2174 node for the complete expression. */
2177 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2183 /* This code is a stripped down version of
2184 build_class_member_access_expr. It does not work to use that
2185 routine directly because it expects the object to be of class
2187 ptrmem_type = TREE_TYPE (ptrmem);
2188 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2189 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2190 /*want_type=*/false);
2191 member_type = cp_build_qualified_type (TREE_TYPE (member),
2192 cp_type_quals (ptrmem_type));
2193 return fold_build3 (COMPONENT_REF, member_type,
2194 ptrmem, member, NULL_TREE);
2197 /* Given an expression PTR for a pointer, return an expression
2198 for the value pointed to.
2199 ERRORSTRING is the name of the operator to appear in error messages.
2201 This function may need to overload OPERATOR_FNNAME.
2202 Must also handle REFERENCE_TYPEs for C++. */
2205 build_x_indirect_ref (tree expr, const char *errorstring)
2207 tree orig_expr = expr;
2210 if (processing_template_decl)
2212 if (type_dependent_expression_p (expr))
2213 return build_min_nt (INDIRECT_REF, expr);
2214 expr = build_non_dependent_expr (expr);
2217 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2218 NULL_TREE, /*overloaded_p=*/NULL);
2220 rval = build_indirect_ref (expr, errorstring);
2222 if (processing_template_decl && rval != error_mark_node)
2223 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2229 build_indirect_ref (tree ptr, const char *errorstring)
2233 if (ptr == error_mark_node)
2234 return error_mark_node;
2236 if (ptr == current_class_ptr)
2237 return current_class_ref;
2239 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2240 ? ptr : decay_conversion (ptr));
2241 type = TREE_TYPE (pointer);
2243 if (POINTER_TYPE_P (type))
2247 If the type of the expression is "pointer to T," the type
2248 of the result is "T."
2250 We must use the canonical variant because certain parts of
2251 the back end, like fold, do pointer comparisons between
2253 tree t = canonical_type_variant (TREE_TYPE (type));
2255 if (VOID_TYPE_P (t))
2257 /* A pointer to incomplete type (other than cv void) can be
2258 dereferenced [expr.unary.op]/1 */
2259 error ("%qT is not a pointer-to-object type", type);
2260 return error_mark_node;
2262 else if (TREE_CODE (pointer) == ADDR_EXPR
2263 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2264 /* The POINTER was something like `&x'. We simplify `*&x' to
2266 return TREE_OPERAND (pointer, 0);
2269 tree ref = build1 (INDIRECT_REF, t, pointer);
2271 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2272 so that we get the proper error message if the result is used
2273 to assign to. Also, &* is supposed to be a no-op. */
2274 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2275 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2276 TREE_SIDE_EFFECTS (ref)
2277 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2281 /* `pointer' won't be an error_mark_node if we were given a
2282 pointer to member, so it's cool to check for this here. */
2283 else if (TYPE_PTR_TO_MEMBER_P (type))
2284 error ("invalid use of %qs on pointer to member", errorstring);
2285 else if (pointer != error_mark_node)
2288 error ("invalid type argument of %qs", errorstring);
2290 error ("invalid type argument");
2292 return error_mark_node;
2295 /* This handles expressions of the form "a[i]", which denotes
2298 This is logically equivalent in C to *(a+i), but we may do it differently.
2299 If A is a variable or a member, we generate a primitive ARRAY_REF.
2300 This avoids forcing the array out of registers, and can work on
2301 arrays that are not lvalues (for example, members of structures returned
2304 If INDEX is of some user-defined type, it must be converted to
2305 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2306 will inherit the type of the array, which will be some pointer type. */
2309 build_array_ref (tree array, tree idx)
2313 error ("subscript missing in array reference");
2314 return error_mark_node;
2317 if (TREE_TYPE (array) == error_mark_node
2318 || TREE_TYPE (idx) == error_mark_node)
2319 return error_mark_node;
2321 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2323 switch (TREE_CODE (array))
2327 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2328 return build2 (COMPOUND_EXPR, TREE_TYPE (value),
2329 TREE_OPERAND (array, 0), value);
2333 return build_conditional_expr
2334 (TREE_OPERAND (array, 0),
2335 build_array_ref (TREE_OPERAND (array, 1), idx),
2336 build_array_ref (TREE_OPERAND (array, 2), idx));
2342 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2346 warn_array_subscript_with_type_char (idx);
2348 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2350 error ("array subscript is not an integer");
2351 return error_mark_node;
2354 /* Apply integral promotions *after* noticing character types.
2355 (It is unclear why we do these promotions -- the standard
2356 does not say that we should. In fact, the natural thing would
2357 seem to be to convert IDX to ptrdiff_t; we're performing
2358 pointer arithmetic.) */
2359 idx = perform_integral_promotions (idx);
2361 /* An array that is indexed by a non-constant
2362 cannot be stored in a register; we must be able to do
2363 address arithmetic on its address.
2364 Likewise an array of elements of variable size. */
2365 if (TREE_CODE (idx) != INTEGER_CST
2366 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2367 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2370 if (!cxx_mark_addressable (array))
2371 return error_mark_node;
2374 /* An array that is indexed by a constant value which is not within
2375 the array bounds cannot be stored in a register either; because we
2376 would get a crash in store_bit_field/extract_bit_field when trying
2377 to access a non-existent part of the register. */
2378 if (TREE_CODE (idx) == INTEGER_CST
2379 && TYPE_DOMAIN (TREE_TYPE (array))
2380 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2382 if (!cxx_mark_addressable (array))
2383 return error_mark_node;
2386 if (pedantic && !lvalue_p (array))
2387 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2389 /* Note in C++ it is valid to subscript a `register' array, since
2390 it is valid to take the address of something with that
2391 storage specification. */
2395 while (TREE_CODE (foo) == COMPONENT_REF)
2396 foo = TREE_OPERAND (foo, 0);
2397 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2398 warning (OPT_Wextra, "subscripting array declared %<register%>");
2401 type = TREE_TYPE (TREE_TYPE (array));
2402 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2403 /* Array ref is const/volatile if the array elements are
2404 or if the array is.. */
2405 TREE_READONLY (rval)
2406 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2407 TREE_SIDE_EFFECTS (rval)
2408 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2409 TREE_THIS_VOLATILE (rval)
2410 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2411 return require_complete_type (fold_if_not_in_template (rval));
2415 tree ar = default_conversion (array);
2416 tree ind = default_conversion (idx);
2418 /* Put the integer in IND to simplify error checking. */
2419 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2426 if (ar == error_mark_node)
2429 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2431 error ("subscripted value is neither array nor pointer");
2432 return error_mark_node;
2434 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2436 error ("array subscript is not an integer");
2437 return error_mark_node;
2440 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2445 /* Resolve a pointer to member function. INSTANCE is the object
2446 instance to use, if the member points to a virtual member.
2448 This used to avoid checking for virtual functions if basetype
2449 has no virtual functions, according to an earlier ANSI draft.
2450 With the final ISO C++ rules, such an optimization is
2451 incorrect: A pointer to a derived member can be static_cast
2452 to pointer-to-base-member, as long as the dynamic object
2453 later has the right member. */
2456 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2458 if (TREE_CODE (function) == OFFSET_REF)
2459 function = TREE_OPERAND (function, 1);
2461 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2463 tree idx, delta, e1, e2, e3, vtbl, basetype;
2464 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2466 tree instance_ptr = *instance_ptrptr;
2467 tree instance_save_expr = 0;
2468 if (instance_ptr == error_mark_node)
2470 if (TREE_CODE (function) == PTRMEM_CST)
2472 /* Extracting the function address from a pmf is only
2473 allowed with -Wno-pmf-conversions. It only works for
2475 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2476 e1 = convert (fntype, e1);
2481 error ("object missing in use of %qE", function);
2482 return error_mark_node;
2486 if (TREE_SIDE_EFFECTS (instance_ptr))
2487 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2489 if (TREE_SIDE_EFFECTS (function))
2490 function = save_expr (function);
2492 /* Start by extracting all the information from the PMF itself. */
2493 e3 = pfn_from_ptrmemfunc (function);
2494 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2495 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2496 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2498 case ptrmemfunc_vbit_in_pfn:
2499 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2500 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2503 case ptrmemfunc_vbit_in_delta:
2504 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2505 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2512 /* Convert down to the right base before using the instance. A
2513 special case is that in a pointer to member of class C, C may
2514 be incomplete. In that case, the function will of course be
2515 a member of C, and no conversion is required. In fact,
2516 lookup_base will fail in that case, because incomplete
2517 classes do not have BINFOs. */
2518 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2519 if (!same_type_ignoring_top_level_qualifiers_p
2520 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2522 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2523 basetype, ba_check, NULL);
2524 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2526 if (instance_ptr == error_mark_node)
2527 return error_mark_node;
2529 /* ...and then the delta in the PMF. */
2530 instance_ptr = build2 (PLUS_EXPR, TREE_TYPE (instance_ptr),
2531 instance_ptr, delta);
2533 /* Hand back the adjusted 'this' argument to our caller. */
2534 *instance_ptrptr = instance_ptr;
2536 /* Next extract the vtable pointer from the object. */
2537 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2539 vtbl = build_indirect_ref (vtbl, NULL);
2541 /* Finally, extract the function pointer from the vtable. */
2542 e2 = fold_build2 (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx);
2543 e2 = build_indirect_ref (e2, NULL);
2544 TREE_CONSTANT (e2) = 1;
2545 TREE_INVARIANT (e2) = 1;
2547 /* When using function descriptors, the address of the
2548 vtable entry is treated as a function pointer. */
2549 if (TARGET_VTABLE_USES_DESCRIPTORS)
2550 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2551 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2553 TREE_TYPE (e2) = TREE_TYPE (e3);
2554 e1 = build_conditional_expr (e1, e2, e3);
2556 /* Make sure this doesn't get evaluated first inside one of the
2557 branches of the COND_EXPR. */
2558 if (instance_save_expr)
2559 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2560 instance_save_expr, e1);
2568 build_function_call (tree function, tree params)
2570 tree fntype, fndecl;
2571 tree coerced_params;
2572 tree name = NULL_TREE;
2574 tree original = function;
2576 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2577 expressions, like those used for ObjC messenger dispatches. */
2578 function = objc_rewrite_function_call (function, params);
2580 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2581 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2582 if (TREE_CODE (function) == NOP_EXPR
2583 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2584 function = TREE_OPERAND (function, 0);
2586 if (TREE_CODE (function) == FUNCTION_DECL)
2588 name = DECL_NAME (function);
2590 mark_used (function);
2593 /* Convert anything with function type to a pointer-to-function. */
2594 if (pedantic && DECL_MAIN_P (function))
2595 pedwarn ("ISO C++ forbids calling %<::main%> from within program");
2597 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2598 (because calling an inline function does not mean the function
2599 needs to be separately compiled). */
2601 if (DECL_INLINE (function))
2602 function = inline_conversion (function);
2604 function = build_addr_func (function);
2610 function = build_addr_func (function);
2613 if (function == error_mark_node)
2614 return error_mark_node;
2616 fntype = TREE_TYPE (function);
2618 if (TYPE_PTRMEMFUNC_P (fntype))
2620 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2621 "function in %<%E (...)%>",
2623 return error_mark_node;
2626 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2627 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2629 if (!((TREE_CODE (fntype) == POINTER_TYPE
2630 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2632 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2634 error ("%qE cannot be used as a function", original);
2635 return error_mark_node;
2638 /* fntype now gets the type of function pointed to. */
2639 fntype = TREE_TYPE (fntype);
2641 /* Convert the parameters to the types declared in the
2642 function prototype, or apply default promotions. */
2644 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2645 params, fndecl, LOOKUP_NORMAL);
2646 if (coerced_params == error_mark_node)
2647 return error_mark_node;
2649 /* Check for errors in format strings and inappropriately
2652 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params,
2653 TYPE_ARG_TYPES (fntype));
2655 return build_cxx_call (function, coerced_params);
2658 /* Convert the actual parameter expressions in the list VALUES
2659 to the types in the list TYPELIST.
2660 If parmdecls is exhausted, or when an element has NULL as its type,
2661 perform the default conversions.
2663 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2665 This is also where warnings about wrong number of args are generated.
2667 Return a list of expressions for the parameters as converted.
2669 Both VALUES and the returned value are chains of TREE_LIST nodes
2670 with the elements of the list in the TREE_VALUE slots of those nodes.
2672 In C++, unspecified trailing parameters can be filled in with their
2673 default arguments, if such were specified. Do so here. */
2676 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2678 tree typetail, valtail;
2679 tree result = NULL_TREE;
2680 const char *called_thing = 0;
2683 /* Argument passing is always copy-initialization. */
2684 flags |= LOOKUP_ONLYCONVERTING;
2688 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2690 if (DECL_NAME (fndecl) == NULL_TREE
2691 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2692 called_thing = "constructor";
2694 called_thing = "member function";
2697 called_thing = "function";
2700 for (valtail = values, typetail = typelist;
2702 valtail = TREE_CHAIN (valtail), i++)
2704 tree type = typetail ? TREE_VALUE (typetail) : 0;
2705 tree val = TREE_VALUE (valtail);
2707 if (val == error_mark_node)
2708 return error_mark_node;
2710 if (type == void_type_node)
2714 error ("too many arguments to %s %q+#D", called_thing, fndecl);
2715 error ("at this point in file");
2718 error ("too many arguments to function");
2719 /* In case anybody wants to know if this argument
2722 TREE_TYPE (tree_last (result)) = error_mark_node;
2726 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2727 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2728 if (TREE_CODE (val) == NOP_EXPR
2729 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2730 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2731 val = TREE_OPERAND (val, 0);
2733 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2735 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2736 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2737 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2738 val = decay_conversion (val);
2741 if (val == error_mark_node)
2742 return error_mark_node;
2746 /* Formal parm type is specified by a function prototype. */
2749 if (!COMPLETE_TYPE_P (complete_type (type)))
2752 error ("parameter %P of %qD has incomplete type %qT",
2755 error ("parameter %P has incomplete type %qT", i, type);
2756 parmval = error_mark_node;
2760 parmval = convert_for_initialization
2761 (NULL_TREE, type, val, flags,
2762 "argument passing", fndecl, i);
2763 parmval = convert_for_arg_passing (type, parmval);
2766 if (parmval == error_mark_node)
2767 return error_mark_node;
2769 result = tree_cons (NULL_TREE, parmval, result);
2773 if (fndecl && DECL_BUILT_IN (fndecl)
2774 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2775 /* Don't do ellipsis conversion for __built_in_constant_p
2776 as this will result in spurious warnings for non-POD
2778 val = require_complete_type (val);
2780 val = convert_arg_to_ellipsis (val);
2782 result = tree_cons (NULL_TREE, val, result);
2786 typetail = TREE_CHAIN (typetail);
2789 if (typetail != 0 && typetail != void_list_node)
2791 /* See if there are default arguments that can be used. */
2792 if (TREE_PURPOSE (typetail)
2793 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2795 for (; typetail != void_list_node; ++i)
2798 = convert_default_arg (TREE_VALUE (typetail),
2799 TREE_PURPOSE (typetail),
2802 if (parmval == error_mark_node)
2803 return error_mark_node;
2805 result = tree_cons (0, parmval, result);
2806 typetail = TREE_CHAIN (typetail);
2807 /* ends with `...'. */
2808 if (typetail == NULL_TREE)
2816 error ("too few arguments to %s %q+#D", called_thing, fndecl);
2817 error ("at this point in file");
2820 error ("too few arguments to function");
2821 return error_mark_node;
2825 return nreverse (result);
2828 /* Build a binary-operation expression, after performing default
2829 conversions on the operands. CODE is the kind of expression to build. */
2832 build_x_binary_op (enum tree_code code, tree arg1, tree arg2,
2842 if (processing_template_decl)
2844 if (type_dependent_expression_p (arg1)
2845 || type_dependent_expression_p (arg2))
2846 return build_min_nt (code, arg1, arg2);
2847 arg1 = build_non_dependent_expr (arg1);
2848 arg2 = build_non_dependent_expr (arg2);
2851 if (code == DOTSTAR_EXPR)
2852 expr = build_m_component_ref (arg1, arg2);
2854 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
2857 if (processing_template_decl && expr != error_mark_node)
2858 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
2863 /* Build a binary-operation expression without default conversions.
2864 CODE is the kind of expression to build.
2865 This function differs from `build' in several ways:
2866 the data type of the result is computed and recorded in it,
2867 warnings are generated if arg data types are invalid,
2868 special handling for addition and subtraction of pointers is known,
2869 and some optimization is done (operations on narrow ints
2870 are done in the narrower type when that gives the same result).
2871 Constant folding is also done before the result is returned.
2873 Note that the operands will never have enumeral types
2874 because either they have just had the default conversions performed
2875 or they have both just been converted to some other type in which
2876 the arithmetic is to be done.
2878 C++: must do special pointer arithmetic when implementing
2879 multiple inheritance, and deal with pointer to member functions. */
2882 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2883 int convert_p ATTRIBUTE_UNUSED)
2886 enum tree_code code0, code1;
2888 const char *invalid_op_diag;
2890 /* Expression code to give to the expression when it is built.
2891 Normally this is CODE, which is what the caller asked for,
2892 but in some special cases we change it. */
2893 enum tree_code resultcode = code;
2895 /* Data type in which the computation is to be performed.
2896 In the simplest cases this is the common type of the arguments. */
2897 tree result_type = NULL;
2899 /* Nonzero means operands have already been type-converted
2900 in whatever way is necessary.
2901 Zero means they need to be converted to RESULT_TYPE. */
2904 /* Nonzero means create the expression with this type, rather than
2906 tree build_type = 0;
2908 /* Nonzero means after finally constructing the expression
2909 convert it to this type. */
2910 tree final_type = 0;
2914 /* Nonzero if this is an operation like MIN or MAX which can
2915 safely be computed in short if both args are promoted shorts.
2916 Also implies COMMON.
2917 -1 indicates a bitwise operation; this makes a difference
2918 in the exact conditions for when it is safe to do the operation
2919 in a narrower mode. */
2922 /* Nonzero if this is a comparison operation;
2923 if both args are promoted shorts, compare the original shorts.
2924 Also implies COMMON. */
2925 int short_compare = 0;
2927 /* Nonzero if this is a right-shift operation, which can be computed on the
2928 original short and then promoted if the operand is a promoted short. */
2929 int short_shift = 0;
2931 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2934 /* True if both operands have arithmetic type. */
2935 bool arithmetic_types_p;
2937 /* Apply default conversions. */
2941 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2942 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2943 || code == TRUTH_XOR_EXPR)
2945 if (!really_overloaded_fn (op0))
2946 op0 = decay_conversion (op0);
2947 if (!really_overloaded_fn (op1))
2948 op1 = decay_conversion (op1);
2952 if (!really_overloaded_fn (op0))
2953 op0 = default_conversion (op0);
2954 if (!really_overloaded_fn (op1))
2955 op1 = default_conversion (op1);
2958 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2959 STRIP_TYPE_NOPS (op0);
2960 STRIP_TYPE_NOPS (op1);
2962 /* DTRT if one side is an overloaded function, but complain about it. */
2963 if (type_unknown_p (op0))
2965 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
2966 if (t != error_mark_node)
2968 pedwarn ("assuming cast to type %qT from overloaded function",
2973 if (type_unknown_p (op1))
2975 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
2976 if (t != error_mark_node)
2978 pedwarn ("assuming cast to type %qT from overloaded function",
2984 type0 = TREE_TYPE (op0);
2985 type1 = TREE_TYPE (op1);
2987 /* The expression codes of the data types of the arguments tell us
2988 whether the arguments are integers, floating, pointers, etc. */
2989 code0 = TREE_CODE (type0);
2990 code1 = TREE_CODE (type1);
2992 /* If an error was already reported for one of the arguments,
2993 avoid reporting another error. */
2995 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
2996 return error_mark_node;
2998 if ((invalid_op_diag
2999 = targetm.invalid_binary_op (code, type0, type1)))
3001 error (invalid_op_diag);
3002 return error_mark_node;
3008 /* Handle the pointer + int case. */
3009 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3010 return cp_pointer_int_sum (PLUS_EXPR, op0, op1);
3011 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
3012 return cp_pointer_int_sum (PLUS_EXPR, op1, op0);
3018 /* Subtraction of two similar pointers.
3019 We must subtract them as integers, then divide by object size. */
3020 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3021 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3023 return pointer_diff (op0, op1, common_type (type0, type1));
3024 /* Handle pointer minus int. Just like pointer plus int. */
3025 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3026 return cp_pointer_int_sum (MINUS_EXPR, op0, op1);
3035 case TRUNC_DIV_EXPR:
3037 case FLOOR_DIV_EXPR:
3038 case ROUND_DIV_EXPR:
3039 case EXACT_DIV_EXPR:
3040 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3041 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3042 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3043 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3045 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
3046 warning (OPT_Wdiv_by_zero, "division by zero in %<%E / 0%>", op0);
3047 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
3048 warning (OPT_Wdiv_by_zero, "division by zero in %<%E / 0.%>", op0);
3050 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3051 code0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3052 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
3053 code1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3055 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
3056 resultcode = RDIV_EXPR;
3058 /* When dividing two signed integers, we have to promote to int.
3059 unless we divide by a constant != -1. Note that default
3060 conversion will have been performed on the operands at this
3061 point, so we have to dig out the original type to find out if
3063 shorten = ((TREE_CODE (op0) == NOP_EXPR
3064 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3065 || (TREE_CODE (op1) == INTEGER_CST
3066 && ! integer_all_onesp (op1)));
3075 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3076 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE))
3080 case TRUNC_MOD_EXPR:
3081 case FLOOR_MOD_EXPR:
3082 if (code1 == INTEGER_TYPE && integer_zerop (op1))
3083 warning (OPT_Wdiv_by_zero, "division by zero in %<%E %% 0%>", op0);
3084 else if (code1 == REAL_TYPE && real_zerop (op1))
3085 warning (OPT_Wdiv_by_zero, "division by zero in %<%E %% 0.%>", op0);
3087 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3089 /* Although it would be tempting to shorten always here, that loses
3090 on some targets, since the modulo instruction is undefined if the
3091 quotient can't be represented in the computation mode. We shorten
3092 only if unsigned or if dividing by something we know != -1. */
3093 shorten = ((TREE_CODE (op0) == NOP_EXPR
3094 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3095 || (TREE_CODE (op1) == INTEGER_CST
3096 && ! integer_all_onesp (op1)));
3101 case TRUTH_ANDIF_EXPR:
3102 case TRUTH_ORIF_EXPR:
3103 case TRUTH_AND_EXPR:
3105 result_type = boolean_type_node;
3108 /* Shift operations: result has same type as first operand;
3109 always convert second operand to int.
3110 Also set SHORT_SHIFT if shifting rightward. */
3113 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3115 result_type = type0;
3116 if (TREE_CODE (op1) == INTEGER_CST)
3118 if (tree_int_cst_lt (op1, integer_zero_node))
3119 warning (0, "right shift count is negative");
3122 if (! integer_zerop (op1))
3124 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3125 warning (0, "right shift count >= width of type");
3128 /* Convert the shift-count to an integer, regardless of
3129 size of value being shifted. */
3130 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3131 op1 = cp_convert (integer_type_node, op1);
3132 /* Avoid converting op1 to result_type later. */
3138 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3140 result_type = type0;
3141 if (TREE_CODE (op1) == INTEGER_CST)
3143 if (tree_int_cst_lt (op1, integer_zero_node))
3144 warning (0, "left shift count is negative");
3145 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3146 warning (0, "left shift count >= width of type");
3148 /* Convert the shift-count to an integer, regardless of
3149 size of value being shifted. */
3150 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3151 op1 = cp_convert (integer_type_node, op1);
3152 /* Avoid converting op1 to result_type later. */
3159 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3161 result_type = type0;
3162 if (TREE_CODE (op1) == INTEGER_CST)
3164 if (tree_int_cst_lt (op1, integer_zero_node))
3165 warning (0, "%s rotate count is negative",
3166 (code == LROTATE_EXPR) ? "left" : "right");
3167 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3168 warning (0, "%s rotate count >= width of type",
3169 (code == LROTATE_EXPR) ? "left" : "right");
3171 /* Convert the shift-count to an integer, regardless of
3172 size of value being shifted. */
3173 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3174 op1 = cp_convert (integer_type_node, op1);
3180 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
3181 warning (OPT_Wfloat_equal,
3182 "comparing floating point with == or != is unsafe");
3183 if ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3184 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0)))
3185 warning (OPT_Wstring_literal_comparison,
3186 "comparison with string literal");
3188 build_type = boolean_type_node;
3189 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3190 || code0 == COMPLEX_TYPE)
3191 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3192 || code1 == COMPLEX_TYPE))
3194 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3195 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3196 result_type = composite_pointer_type (type0, type1, op0, op1,
3198 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3199 && null_ptr_cst_p (op1))
3200 result_type = type0;
3201 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3202 && null_ptr_cst_p (op0))
3203 result_type = type1;
3204 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3206 result_type = type0;
3207 error ("ISO C++ forbids comparison between pointer and integer");
3209 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3211 result_type = type1;
3212 error ("ISO C++ forbids comparison between pointer and integer");
3214 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3216 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3217 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3218 result_type = TREE_TYPE (op0);
3220 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3221 return cp_build_binary_op (code, op1, op0);
3222 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
3223 && same_type_p (type0, type1))
3225 /* E will be the final comparison. */
3227 /* E1 and E2 are for scratch. */
3235 if (TREE_SIDE_EFFECTS (op0))
3236 op0 = save_expr (op0);
3237 if (TREE_SIDE_EFFECTS (op1))
3238 op1 = save_expr (op1);
3243 && (!op0.pfn || op0.delta == op1.delta))
3245 The reason for the `!op0.pfn' bit is that a NULL
3246 pointer-to-member is any member with a zero PFN; the
3247 DELTA field is unspecified. */
3248 pfn0 = pfn_from_ptrmemfunc (op0);
3249 pfn1 = pfn_from_ptrmemfunc (op1);
3250 delta0 = build_ptrmemfunc_access_expr (op0,
3252 delta1 = build_ptrmemfunc_access_expr (op1,
3254 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
3255 e2 = cp_build_binary_op (EQ_EXPR,
3257 cp_convert (TREE_TYPE (pfn0),
3258 integer_zero_node));
3259 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
3260 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3261 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3262 if (code == EQ_EXPR)
3264 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3268 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3269 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3271 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3272 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3280 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3281 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3283 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3284 result_type = composite_pointer_type (type0, type1, op0, op1,
3292 if (TREE_CODE (orig_op0) == STRING_CST
3293 || TREE_CODE (orig_op1) == STRING_CST)
3294 warning (OPT_Wstring_literal_comparison,
3295 "comparison with string literal");
3297 build_type = boolean_type_node;
3298 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3299 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3301 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3302 result_type = composite_pointer_type (type0, type1, op0, op1,
3304 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3305 && integer_zerop (op1))
3306 result_type = type0;
3307 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3308 && integer_zerop (op0))
3309 result_type = type1;
3310 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3312 result_type = type0;
3313 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3315 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3317 result_type = type1;
3318 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3322 case UNORDERED_EXPR:
3329 build_type = integer_type_node;
3330 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3332 error ("unordered comparison on non-floating point argument");
3333 return error_mark_node;
3342 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3343 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3344 || code1 == COMPLEX_TYPE)))
3345 arithmetic_types_p = 1;
3348 arithmetic_types_p = 0;
3349 /* Vector arithmetic is only allowed when both sides are vectors. */
3350 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3352 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3353 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3356 binary_op_error (code);
3357 return error_mark_node;
3359 arithmetic_types_p = 1;
3362 /* Determine the RESULT_TYPE, if it is not already known. */
3364 && arithmetic_types_p
3365 && (shorten || common || short_compare))
3366 result_type = common_type (type0, type1);
3370 error ("invalid operands of types %qT and %qT to binary %qO",
3371 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3372 return error_mark_node;
3375 /* If we're in a template, the only thing we need to know is the
3377 if (processing_template_decl)
3378 return build2 (resultcode,
3379 build_type ? build_type : result_type,
3382 if (arithmetic_types_p)
3384 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3386 /* For certain operations (which identify themselves by shorten != 0)
3387 if both args were extended from the same smaller type,
3388 do the arithmetic in that type and then extend.
3390 shorten !=0 and !=1 indicates a bitwise operation.
3391 For them, this optimization is safe only if
3392 both args are zero-extended or both are sign-extended.
3393 Otherwise, we might change the result.
3394 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3395 but calculated in (unsigned short) it would be (unsigned short)-1. */
3397 if (shorten && none_complex)
3399 int unsigned0, unsigned1;
3400 tree arg0 = get_narrower (op0, &unsigned0);
3401 tree arg1 = get_narrower (op1, &unsigned1);
3402 /* UNS is 1 if the operation to be done is an unsigned one. */
3403 int uns = TYPE_UNSIGNED (result_type);
3406 final_type = result_type;
3408 /* Handle the case that OP0 does not *contain* a conversion
3409 but it *requires* conversion to FINAL_TYPE. */
3411 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3412 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
3413 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3414 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
3416 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3418 /* For bitwise operations, signedness of nominal type
3419 does not matter. Consider only how operands were extended. */
3423 /* Note that in all three cases below we refrain from optimizing
3424 an unsigned operation on sign-extended args.
3425 That would not be valid. */
3427 /* Both args variable: if both extended in same way
3428 from same width, do it in that width.
3429 Do it unsigned if args were zero-extended. */
3430 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3431 < TYPE_PRECISION (result_type))
3432 && (TYPE_PRECISION (TREE_TYPE (arg1))
3433 == TYPE_PRECISION (TREE_TYPE (arg0)))
3434 && unsigned0 == unsigned1
3435 && (unsigned0 || !uns))
3436 result_type = c_common_signed_or_unsigned_type
3437 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3438 else if (TREE_CODE (arg0) == INTEGER_CST
3439 && (unsigned1 || !uns)
3440 && (TYPE_PRECISION (TREE_TYPE (arg1))
3441 < TYPE_PRECISION (result_type))
3442 && (type = c_common_signed_or_unsigned_type
3443 (unsigned1, TREE_TYPE (arg1)),
3444 int_fits_type_p (arg0, type)))
3446 else if (TREE_CODE (arg1) == INTEGER_CST
3447 && (unsigned0 || !uns)
3448 && (TYPE_PRECISION (TREE_TYPE (arg0))
3449 < TYPE_PRECISION (result_type))
3450 && (type = c_common_signed_or_unsigned_type
3451 (unsigned0, TREE_TYPE (arg0)),
3452 int_fits_type_p (arg1, type)))
3456 /* Shifts can be shortened if shifting right. */
3461 tree arg0 = get_narrower (op0, &unsigned_arg);
3463 final_type = result_type;
3465 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3466 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
3468 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3469 /* We can shorten only if the shift count is less than the
3470 number of bits in the smaller type size. */
3471 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3472 /* If arg is sign-extended and then unsigned-shifted,
3473 we can simulate this with a signed shift in arg's type
3474 only if the extended result is at least twice as wide
3475 as the arg. Otherwise, the shift could use up all the
3476 ones made by sign-extension and bring in zeros.
3477 We can't optimize that case at all, but in most machines
3478 it never happens because available widths are 2**N. */
3479 && (!TYPE_UNSIGNED (final_type)
3481 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3482 <= TYPE_PRECISION (result_type))))
3484 /* Do an unsigned shift if the operand was zero-extended. */
3486 = c_common_signed_or_unsigned_type (unsigned_arg,
3488 /* Convert value-to-be-shifted to that type. */
3489 if (TREE_TYPE (op0) != result_type)
3490 op0 = cp_convert (result_type, op0);
3495 /* Comparison operations are shortened too but differently.
3496 They identify themselves by setting short_compare = 1. */
3500 /* Don't write &op0, etc., because that would prevent op0
3501 from being kept in a register.
3502 Instead, make copies of the our local variables and
3503 pass the copies by reference, then copy them back afterward. */
3504 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3505 enum tree_code xresultcode = resultcode;
3507 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3509 return cp_convert (boolean_type_node, val);
3510 op0 = xop0, op1 = xop1;
3512 resultcode = xresultcode;
3515 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3516 && warn_sign_compare
3517 /* Do not warn until the template is instantiated; we cannot
3518 bound the ranges of the arguments until that point. */
3519 && !processing_template_decl)
3521 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
3522 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3524 int unsignedp0, unsignedp1;
3525 tree primop0 = get_narrower (op0, &unsignedp0);
3526 tree primop1 = get_narrower (op1, &unsignedp1);
3528 /* Check for comparison of different enum types. */
3529 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3530 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3531 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3532 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3534 warning (0, "comparison between types %q#T and %q#T",
3535 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3538 /* Give warnings for comparisons between signed and unsigned
3539 quantities that may fail. */
3540 /* Do the checking based on the original operand trees, so that
3541 casts will be considered, but default promotions won't be. */
3543 /* Do not warn if the comparison is being done in a signed type,
3544 since the signed type will only be chosen if it can represent
3545 all the values of the unsigned type. */
3546 if (!TYPE_UNSIGNED (result_type))
3548 /* Do not warn if both operands are unsigned. */
3549 else if (op0_signed == op1_signed)
3551 /* Do not warn if the signed quantity is an unsuffixed
3552 integer literal (or some static constant expression
3553 involving such literals or a conditional expression
3554 involving such literals) and it is non-negative. */
3555 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3556 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3558 /* Do not warn if the comparison is an equality operation,
3559 the unsigned quantity is an integral constant and it does
3560 not use the most significant bit of result_type. */
3561 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3562 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3563 && int_fits_type_p (orig_op1, c_common_signed_type
3565 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3566 && int_fits_type_p (orig_op0, c_common_signed_type
3570 warning (0, "comparison between signed and unsigned integer expressions");
3572 /* Warn if two unsigned values are being compared in a size
3573 larger than their original size, and one (and only one) is the
3574 result of a `~' operator. This comparison will always fail.
3576 Also warn if one operand is a constant, and the constant does not
3577 have all bits set that are set in the ~ operand when it is
3580 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3581 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3583 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3584 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3585 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3586 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3588 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3591 HOST_WIDE_INT constant, mask;
3595 if (host_integerp (primop0, 0))
3598 unsignedp = unsignedp1;
3599 constant = tree_low_cst (primop0, 0);
3604 unsignedp = unsignedp0;
3605 constant = tree_low_cst (primop1, 0);
3608 bits = TYPE_PRECISION (TREE_TYPE (primop));
3609 if (bits < TYPE_PRECISION (result_type)
3610 && bits < HOST_BITS_PER_LONG && unsignedp)
3612 mask = (~ (HOST_WIDE_INT) 0) << bits;
3613 if ((mask & constant) != mask)
3614 warning (0, "comparison of promoted ~unsigned with constant");
3617 else if (unsignedp0 && unsignedp1
3618 && (TYPE_PRECISION (TREE_TYPE (primop0))
3619 < TYPE_PRECISION (result_type))
3620 && (TYPE_PRECISION (TREE_TYPE (primop1))
3621 < TYPE_PRECISION (result_type)))
3622 warning (0, "comparison of promoted ~unsigned with unsigned");
3627 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3628 Then the expression will be built.
3629 It will be given type FINAL_TYPE if that is nonzero;
3630 otherwise, it will be given type RESULT_TYPE. */
3632 /* Issue warnings about peculiar, but valid, uses of NULL. */
3633 if (/* It's reasonable to use pointer values as operands of &&
3634 and ||, so NULL is no exception. */
3635 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3636 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3637 (orig_op0 == null_node
3638 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3639 /* Or vice versa. */
3640 || (orig_op1 == null_node
3641 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3642 /* Or, both are NULL and the operation was not a comparison. */
3643 || (orig_op0 == null_node && orig_op1 == null_node
3644 && code != EQ_EXPR && code != NE_EXPR)))
3645 /* Some sort of arithmetic operation involving NULL was
3646 performed. Note that pointer-difference and pointer-addition
3647 have already been handled above, and so we don't end up here in
3649 warning (0, "NULL used in arithmetic");
3653 if (TREE_TYPE (op0) != result_type)
3654 op0 = cp_convert (result_type, op0);
3655 if (TREE_TYPE (op1) != result_type)
3656 op1 = cp_convert (result_type, op1);
3658 if (op0 == error_mark_node || op1 == error_mark_node)
3659 return error_mark_node;
3662 if (build_type == NULL_TREE)
3663 build_type = result_type;
3665 result = build2 (resultcode, build_type, op0, op1);
3666 result = fold_if_not_in_template (result);
3667 if (final_type != 0)
3668 result = cp_convert (final_type, result);
3672 /* Return a tree for the sum or difference (RESULTCODE says which)
3673 of pointer PTROP and integer INTOP. */
3676 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
3678 tree res_type = TREE_TYPE (ptrop);
3680 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3681 in certain circumstance (when it's valid to do so). So we need
3682 to make sure it's complete. We don't need to check here, if we
3683 can actually complete it at all, as those checks will be done in
3684 pointer_int_sum() anyway. */
3685 complete_type (TREE_TYPE (res_type));
3687 return pointer_int_sum (resultcode, ptrop,
3688 fold_if_not_in_template (intop));
3691 /* Return a tree for the difference of pointers OP0 and OP1.
3692 The resulting tree has type int. */
3695 pointer_diff (tree op0, tree op1, tree ptrtype)
3698 tree restype = ptrdiff_type_node;
3699 tree target_type = TREE_TYPE (ptrtype);
3701 if (!complete_type_or_else (target_type, NULL_TREE))
3702 return error_mark_node;
3704 if (pedantic || warn_pointer_arith)
3706 if (TREE_CODE (target_type) == VOID_TYPE)
3707 pedwarn ("ISO C++ forbids using pointer of type %<void *%> in subtraction");
3708 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3709 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3710 if (TREE_CODE (target_type) == METHOD_TYPE)
3711 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3714 /* First do the subtraction as integers;
3715 then drop through to build the divide operator. */
3717 op0 = cp_build_binary_op (MINUS_EXPR,
3718 cp_convert (restype, op0),
3719 cp_convert (restype, op1));
3721 /* This generates an error if op1 is a pointer to an incomplete type. */
3722 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3723 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3725 op1 = (TYPE_PTROB_P (ptrtype)
3726 ? size_in_bytes (target_type)
3727 : integer_one_node);
3729 /* Do the division. */
3731 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3732 return fold_if_not_in_template (result);
3735 /* Construct and perhaps optimize a tree representation
3736 for a unary operation. CODE, a tree_code, specifies the operation
3737 and XARG is the operand. */
3740 build_x_unary_op (enum tree_code code, tree xarg)
3742 tree orig_expr = xarg;
3746 if (processing_template_decl)
3748 if (type_dependent_expression_p (xarg))
3749 return build_min_nt (code, xarg, NULL_TREE);
3751 xarg = build_non_dependent_expr (xarg);
3756 /* [expr.unary.op] says:
3758 The address of an object of incomplete type can be taken.
3760 (And is just the ordinary address operator, not an overloaded
3761 "operator &".) However, if the type is a template
3762 specialization, we must complete the type at this point so that
3763 an overloaded "operator &" will be available if required. */
3764 if (code == ADDR_EXPR
3765 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3766 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
3767 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
3768 || (TREE_CODE (xarg) == OFFSET_REF)))
3769 /* Don't look for a function. */;
3771 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
3772 /*overloaded_p=*/NULL);
3773 if (!exp && code == ADDR_EXPR)
3775 /* A pointer to member-function can be formed only by saying
3777 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3778 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3780 if (TREE_CODE (xarg) != OFFSET_REF
3781 || !TYPE_P (TREE_OPERAND (xarg, 0)))
3783 error ("invalid use of %qE to form a pointer-to-member-function",
3785 if (TREE_CODE (xarg) != OFFSET_REF)
3786 inform (" a qualified-id is required");
3787 return error_mark_node;
3791 error ("parentheses around %qE cannot be used to form a"
3792 " pointer-to-member-function",
3794 PTRMEM_OK_P (xarg) = 1;
3798 if (TREE_CODE (xarg) == OFFSET_REF)
3800 ptrmem = PTRMEM_OK_P (xarg);
3802 if (!ptrmem && !flag_ms_extensions
3803 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3805 /* A single non-static member, make sure we don't allow a
3806 pointer-to-member. */
3807 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
3808 TREE_OPERAND (xarg, 0),
3809 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3810 PTRMEM_OK_P (xarg) = ptrmem;
3813 else if (TREE_CODE (xarg) == TARGET_EXPR)
3814 warning (0, "taking address of temporary");
3815 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3818 if (processing_template_decl && exp != error_mark_node)
3819 exp = build_min_non_dep (code, exp, orig_expr,
3820 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
3821 if (TREE_CODE (exp) == ADDR_EXPR)
3822 PTRMEM_OK_P (exp) = ptrmem;
3826 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3827 constants, where a null value is represented by an INTEGER_CST of
3831 cp_truthvalue_conversion (tree expr)
3833 tree type = TREE_TYPE (expr);
3834 if (TYPE_PTRMEM_P (type))
3835 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3837 return c_common_truthvalue_conversion (expr);
3840 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3843 condition_conversion (tree expr)
3846 if (processing_template_decl)
3848 t = perform_implicit_conversion (boolean_type_node, expr);
3849 t = fold_build_cleanup_point_expr (boolean_type_node, t);
3853 /* Return an ADDR_EXPR giving the address of T. This function
3854 attempts no optimizations or simplifications; it is a low-level
3858 build_address (tree t)
3862 if (error_operand_p (t) || !cxx_mark_addressable (t))
3863 return error_mark_node;
3865 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
3870 /* Return a NOP_EXPR converting EXPR to TYPE. */
3873 build_nop (tree type, tree expr)
3875 if (type == error_mark_node || error_operand_p (expr))
3877 return build1 (NOP_EXPR, type, expr);
3880 /* C++: Must handle pointers to members.
3882 Perhaps type instantiation should be extended to handle conversion
3883 from aggregates to types we don't yet know we want? (Or are those
3884 cases typically errors which should be reported?)
3886 NOCONVERT nonzero suppresses the default promotions
3887 (such as from short to int). */
3890 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3892 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3895 const char *errstring = NULL;
3897 const char *invalid_op_diag;
3899 if (arg == error_mark_node)
3900 return error_mark_node;
3902 if ((invalid_op_diag
3903 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
3908 error (invalid_op_diag);
3909 return error_mark_node;
3914 case UNARY_PLUS_EXPR:
3917 int flags = WANT_ARITH | WANT_ENUM;
3918 /* Unary plus (but not unary minus) is allowed on pointers. */
3919 if (code == UNARY_PLUS_EXPR)
3920 flags |= WANT_POINTER;
3921 arg = build_expr_type_conversion (flags, arg, true);
3923 errstring = (code == NEGATE_EXPR
3924 ? "wrong type argument to unary minus"
3925 : "wrong type argument to unary plus");
3928 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3929 arg = perform_integral_promotions (arg);
3931 /* Make sure the result is not an lvalue: a unary plus or minus
3932 expression is always a rvalue. */
3939 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3943 arg = default_conversion (arg);
3945 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
3947 errstring = "wrong type argument to bit-complement";
3948 else if (!noconvert)
3949 arg = perform_integral_promotions (arg);
3953 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3954 errstring = "wrong type argument to abs";
3955 else if (!noconvert)
3956 arg = default_conversion (arg);
3960 /* Conjugating a real value is a no-op, but allow it anyway. */
3961 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3962 errstring = "wrong type argument to conjugation";
3963 else if (!noconvert)
3964 arg = default_conversion (arg);
3967 case TRUTH_NOT_EXPR:
3968 arg = perform_implicit_conversion (boolean_type_node, arg);
3969 val = invert_truthvalue (arg);
3970 if (arg != error_mark_node)
3972 errstring = "in argument to unary !";
3979 if (TREE_CODE (arg) == COMPLEX_CST)
3980 return TREE_REALPART (arg);
3981 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3983 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3984 return fold_if_not_in_template (arg);
3990 if (TREE_CODE (arg) == COMPLEX_CST)
3991 return TREE_IMAGPART (arg);
3992 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3994 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3995 return fold_if_not_in_template (arg);
3998 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4000 case PREINCREMENT_EXPR:
4001 case POSTINCREMENT_EXPR:
4002 case PREDECREMENT_EXPR:
4003 case POSTDECREMENT_EXPR:
4004 /* Handle complex lvalues (when permitted)
4005 by reduction to simpler cases. */
4007 val = unary_complex_lvalue (code, arg);
4011 /* Increment or decrement the real part of the value,
4012 and don't change the imaginary part. */
4013 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4017 arg = stabilize_reference (arg);
4018 real = build_unary_op (REALPART_EXPR, arg, 1);
4019 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
4020 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4021 build_unary_op (code, real, 1), imag);
4024 /* Report invalid types. */
4026 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4029 if (code == PREINCREMENT_EXPR)
4030 errstring ="no pre-increment operator for type";
4031 else if (code == POSTINCREMENT_EXPR)
4032 errstring ="no post-increment operator for type";
4033 else if (code == PREDECREMENT_EXPR)
4034 errstring ="no pre-decrement operator for type";
4036 errstring ="no post-decrement operator for type";
4040 /* Report something read-only. */
4042 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4043 || TREE_READONLY (arg))
4044 readonly_error (arg, ((code == PREINCREMENT_EXPR
4045 || code == POSTINCREMENT_EXPR)
4046 ? "increment" : "decrement"),
4051 tree result_type = TREE_TYPE (arg);
4053 arg = get_unwidened (arg, 0);
4054 argtype = TREE_TYPE (arg);
4056 /* ARM $5.2.5 last annotation says this should be forbidden. */
4057 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4058 pedwarn ("ISO C++ forbids %sing an enum",
4059 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4060 ? "increment" : "decrement");
4062 /* Compute the increment. */
4064 if (TREE_CODE (argtype) == POINTER_TYPE)
4066 tree type = complete_type (TREE_TYPE (argtype));
4068 if (!COMPLETE_OR_VOID_TYPE_P (type))
4069 error ("cannot %s a pointer to incomplete type %qT",
4070 ((code == PREINCREMENT_EXPR
4071 || code == POSTINCREMENT_EXPR)
4072 ? "increment" : "decrement"), TREE_TYPE (argtype));
4073 else if ((pedantic || warn_pointer_arith)
4074 && !TYPE_PTROB_P (argtype))
4075 pedwarn ("ISO C++ forbids %sing a pointer of type %qT",
4076 ((code == PREINCREMENT_EXPR
4077 || code == POSTINCREMENT_EXPR)
4078 ? "increment" : "decrement"), argtype);
4079 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4082 inc = integer_one_node;
4084 inc = cp_convert (argtype, inc);
4086 /* Handle incrementing a cast-expression. */
4088 switch (TREE_CODE (arg))
4093 case FIX_TRUNC_EXPR:
4094 case FIX_FLOOR_EXPR:
4095 case FIX_ROUND_EXPR:
4098 tree incremented, modify, value, compound;
4099 if (! lvalue_p (arg) && pedantic)
4100 pedwarn ("cast to non-reference type used as lvalue");
4101 arg = stabilize_reference (arg);
4102 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
4105 value = save_expr (arg);
4106 incremented = build2 (((code == PREINCREMENT_EXPR
4107 || code == POSTINCREMENT_EXPR)
4108 ? PLUS_EXPR : MINUS_EXPR),
4109 argtype, value, inc);
4111 modify = build_modify_expr (arg, NOP_EXPR, incremented);
4112 compound = build2 (COMPOUND_EXPR, TREE_TYPE (arg),
4115 /* Eliminate warning about unused result of + or -. */
4116 TREE_NO_WARNING (compound) = 1;
4124 /* Complain about anything else that is not a true lvalue. */
4125 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4126 || code == POSTINCREMENT_EXPR)
4127 ? lv_increment : lv_decrement)))
4128 return error_mark_node;
4130 /* Forbid using -- on `bool'. */
4131 if (TREE_TYPE (arg) == boolean_type_node)
4133 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4135 error ("invalid use of %<--%> on bool variable %qD", arg);
4136 return error_mark_node;
4138 val = boolean_increment (code, arg);
4141 val = build2 (code, TREE_TYPE (arg), arg, inc);
4143 TREE_SIDE_EFFECTS (val) = 1;
4144 return cp_convert (result_type, val);
4148 /* Note that this operation never does default_conversion
4149 regardless of NOCONVERT. */
4151 argtype = lvalue_type (arg);
4153 if (TREE_CODE (arg) == OFFSET_REF)
4156 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4158 tree type = build_pointer_type (TREE_TYPE (argtype));
4159 arg = build1 (CONVERT_EXPR, type, arg);
4162 else if (pedantic && DECL_MAIN_P (arg))
4164 pedwarn ("ISO C++ forbids taking address of function %<::main%>");
4166 /* Let &* cancel out to simplify resulting code. */
4167 if (TREE_CODE (arg) == INDIRECT_REF)
4169 /* We don't need to have `current_class_ptr' wrapped in a
4170 NON_LVALUE_EXPR node. */
4171 if (arg == current_class_ref)
4172 return current_class_ptr;
4174 arg = TREE_OPERAND (arg, 0);
4175 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4177 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4178 arg = build1 (CONVERT_EXPR, type, arg);
4181 /* Don't let this be an lvalue. */
4186 /* Uninstantiated types are all functions. Taking the
4187 address of a function is a no-op, so just return the
4190 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4191 || !IDENTIFIER_OPNAME_P (arg));
4193 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4194 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4196 /* They're trying to take the address of a unique non-static
4197 member function. This is ill-formed (except in MS-land),
4198 but let's try to DTRT.
4199 Note: We only handle unique functions here because we don't
4200 want to complain if there's a static overload; non-unique
4201 cases will be handled by instantiate_type. But we need to
4202 handle this case here to allow casts on the resulting PMF.
4203 We could defer this in non-MS mode, but it's easier to give
4204 a useful error here. */
4206 /* Inside constant member functions, the `this' pointer
4207 contains an extra const qualifier. TYPE_MAIN_VARIANT
4208 is used here to remove this const from the diagnostics
4209 and the created OFFSET_REF. */
4210 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4211 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4213 if (! flag_ms_extensions)
4215 tree name = DECL_NAME (fn);
4216 if (current_class_type
4217 && TREE_OPERAND (arg, 0) == current_class_ref)
4218 /* An expression like &memfn. */
4219 pedwarn ("ISO C++ forbids taking the address of an unqualified"
4220 " or parenthesized non-static member function to form"
4221 " a pointer to member function. Say %<&%T::%D%>",
4224 pedwarn ("ISO C++ forbids taking the address of a bound member"
4225 " function to form a pointer to member function."
4229 arg = build_offset_ref (base, fn, /*address_p=*/true);
4233 if (type_unknown_p (arg))
4234 return build1 (ADDR_EXPR, unknown_type_node, arg);
4236 /* Handle complex lvalues (when permitted)
4237 by reduction to simpler cases. */
4238 val = unary_complex_lvalue (code, arg);
4242 switch (TREE_CODE (arg))
4247 case FIX_TRUNC_EXPR:
4248 case FIX_FLOOR_EXPR:
4249 case FIX_ROUND_EXPR:
4251 if (! lvalue_p (arg) && pedantic)
4252 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4256 arg = OVL_CURRENT (arg);
4260 /* Turn a reference to a non-static data member into a
4261 pointer-to-member. */
4266 if (!PTRMEM_OK_P (arg))
4267 return build_unary_op (code, arg, 0);
4269 t = TREE_OPERAND (arg, 1);
4270 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4272 error ("cannot create pointer to reference member %qD", t);
4273 return error_mark_node;
4276 type = build_ptrmem_type (context_for_name_lookup (t),
4278 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4286 /* Anything not already handled and not a true memory reference
4288 if (TREE_CODE (argtype) != FUNCTION_TYPE
4289 && TREE_CODE (argtype) != METHOD_TYPE
4290 && TREE_CODE (arg) != OFFSET_REF
4291 /* Permit users to take the address of a compound-literal
4292 with sufficient simple elements. */
4293 && !(COMPOUND_LITERAL_P (arg) && TREE_STATIC (arg))
4294 && !lvalue_or_else (arg, lv_addressof))
4295 return error_mark_node;
4297 if (argtype != error_mark_node)
4298 argtype = build_pointer_type (argtype);
4300 /* In a template, we are processing a non-dependent expression
4301 so we can just form an ADDR_EXPR with the correct type. */
4302 if (processing_template_decl)
4304 val = build_address (arg);
4305 if (TREE_CODE (arg) == OFFSET_REF)
4306 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4310 /* If the user has taken the address of the compound literal,
4311 create a variable to contain the value of the literal and
4312 then return the address of that variable. */
4313 if (COMPOUND_LITERAL_P (arg))
4316 gcc_assert (TREE_STATIC (arg));
4317 var = create_temporary_var (TREE_TYPE (arg));
4318 TREE_STATIC (var) = 1;
4319 set_compound_literal_name (var);
4320 initialize_artificial_var (var, arg);
4321 arg = pushdecl (var);
4322 /* Since each compound literal is unique, pushdecl should
4323 never find a pre-existing variable with the same
4325 gcc_assert (arg == var);
4328 if (TREE_CODE (arg) != COMPONENT_REF)
4330 val = build_address (arg);
4331 if (TREE_CODE (arg) == OFFSET_REF)
4332 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4334 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4336 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4338 /* We can only get here with a single static member
4340 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4341 && DECL_STATIC_FUNCTION_P (fn));
4343 val = build_address (fn);
4344 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4345 /* Do not lose object's side effects. */
4346 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4347 TREE_OPERAND (arg, 0), val);
4349 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4351 error ("attempt to take address of bit-field structure member %qD",
4352 TREE_OPERAND (arg, 1));
4353 return error_mark_node;
4357 tree object = TREE_OPERAND (arg, 0);
4358 tree field = TREE_OPERAND (arg, 1);
4359 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4360 (TREE_TYPE (object), decl_type_context (field)));
4361 val = build_address (arg);
4364 if (TREE_CODE (argtype) == POINTER_TYPE
4365 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4367 build_ptrmemfunc_type (argtype);
4368 val = build_ptrmemfunc (argtype, val, 0,
4369 /*c_cast_p=*/false);
4381 argtype = TREE_TYPE (arg);
4382 return fold_if_not_in_template (build1 (code, argtype, arg));
4385 error ("%s", errstring);
4386 return error_mark_node;
4389 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4390 for certain kinds of expressions which are not really lvalues
4391 but which we can accept as lvalues.
4393 If ARG is not a kind of expression we can handle, return
4397 unary_complex_lvalue (enum tree_code code, tree arg)
4399 /* Inside a template, making these kinds of adjustments is
4400 pointless; we are only concerned with the type of the
4402 if (processing_template_decl)
4405 /* Handle (a, b) used as an "lvalue". */
4406 if (TREE_CODE (arg) == COMPOUND_EXPR)
4408 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4409 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4410 TREE_OPERAND (arg, 0), real_result);
4413 /* Handle (a ? b : c) used as an "lvalue". */
4414 if (TREE_CODE (arg) == COND_EXPR
4415 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4416 return rationalize_conditional_expr (code, arg);
4418 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4419 if (TREE_CODE (arg) == MODIFY_EXPR
4420 || TREE_CODE (arg) == PREINCREMENT_EXPR
4421 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4423 tree lvalue = TREE_OPERAND (arg, 0);
4424 if (TREE_SIDE_EFFECTS (lvalue))
4426 lvalue = stabilize_reference (lvalue);
4427 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4428 lvalue, TREE_OPERAND (arg, 1));
4430 return unary_complex_lvalue
4431 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4434 if (code != ADDR_EXPR)
4437 /* Handle (a = b) used as an "lvalue" for `&'. */
4438 if (TREE_CODE (arg) == MODIFY_EXPR
4439 || TREE_CODE (arg) == INIT_EXPR)
4441 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4442 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4444 TREE_NO_WARNING (arg) = 1;
4448 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4449 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4450 || TREE_CODE (arg) == OFFSET_REF)
4453 /* We permit compiler to make function calls returning
4454 objects of aggregate type look like lvalues. */
4458 if (TREE_CODE (targ) == SAVE_EXPR)
4459 targ = TREE_OPERAND (targ, 0);
4461 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4463 if (TREE_CODE (arg) == SAVE_EXPR)
4466 targ = build_cplus_new (TREE_TYPE (arg), arg);
4467 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4470 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4471 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4472 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4475 /* Don't let anything else be handled specially. */
4479 /* Mark EXP saying that we need to be able to take the
4480 address of it; it should not be allocated in a register.
4481 Value is true if successful.
4483 C++: we do not allow `current_class_ptr' to be addressable. */
4486 cxx_mark_addressable (tree exp)
4491 switch (TREE_CODE (x))
4498 x = TREE_OPERAND (x, 0);
4502 if (x == current_class_ptr)
4504 error ("cannot take the address of %<this%>, which is an rvalue expression");
4505 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4511 /* Caller should not be trying to mark initialized
4512 constant fields addressable. */
4513 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4514 || DECL_IN_AGGR_P (x) == 0
4516 || DECL_EXTERNAL (x));
4521 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4522 && !DECL_ARTIFICIAL (x))
4524 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4527 ("address of explicit register variable %qD requested", x);
4530 else if (extra_warnings)
4532 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
4534 TREE_ADDRESSABLE (x) = 1;
4538 TREE_ADDRESSABLE (x) = 1;
4542 TREE_ADDRESSABLE (x) = 1;
4546 TREE_ADDRESSABLE (x) = 1;
4547 cxx_mark_addressable (TREE_OPERAND (x, 0));
4555 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4558 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4560 tree orig_ifexp = ifexp;
4561 tree orig_op1 = op1;
4562 tree orig_op2 = op2;
4565 if (processing_template_decl)
4567 /* The standard says that the expression is type-dependent if
4568 IFEXP is type-dependent, even though the eventual type of the
4569 expression doesn't dependent on IFEXP. */
4570 if (type_dependent_expression_p (ifexp)
4571 /* As a GNU extension, the middle operand may be omitted. */
4572 || (op1 && type_dependent_expression_p (op1))
4573 || type_dependent_expression_p (op2))
4574 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4575 ifexp = build_non_dependent_expr (ifexp);
4577 op1 = build_non_dependent_expr (op1);
4578 op2 = build_non_dependent_expr (op2);
4581 expr = build_conditional_expr (ifexp, op1, op2);
4582 if (processing_template_decl && expr != error_mark_node)
4583 return build_min_non_dep (COND_EXPR, expr,
4584 orig_ifexp, orig_op1, orig_op2);
4588 /* Given a list of expressions, return a compound expression
4589 that performs them all and returns the value of the last of them. */
4591 tree build_x_compound_expr_from_list (tree list, const char *msg)
4593 tree expr = TREE_VALUE (list);
4595 if (TREE_CHAIN (list))
4598 pedwarn ("%s expression list treated as compound expression", msg);
4600 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4601 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4607 /* Handle overloading of the ',' operator when needed. */
4610 build_x_compound_expr (tree op1, tree op2)
4613 tree orig_op1 = op1;
4614 tree orig_op2 = op2;
4616 if (processing_template_decl)
4618 if (type_dependent_expression_p (op1)
4619 || type_dependent_expression_p (op2))
4620 return build_min_nt (COMPOUND_EXPR, op1, op2);
4621 op1 = build_non_dependent_expr (op1);
4622 op2 = build_non_dependent_expr (op2);
4625 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4626 /*overloaded_p=*/NULL);
4628 result = build_compound_expr (op1, op2);
4630 if (processing_template_decl && result != error_mark_node)
4631 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4636 /* Build a compound expression. */
4639 build_compound_expr (tree lhs, tree rhs)
4641 lhs = convert_to_void (lhs, "left-hand operand of comma");
4643 if (lhs == error_mark_node || rhs == error_mark_node)
4644 return error_mark_node;
4646 if (TREE_CODE (rhs) == TARGET_EXPR)
4648 /* If the rhs is a TARGET_EXPR, then build the compound
4649 expression inside the target_expr's initializer. This
4650 helps the compiler to eliminate unnecessary temporaries. */
4651 tree init = TREE_OPERAND (rhs, 1);
4653 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4654 TREE_OPERAND (rhs, 1) = init;
4659 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4662 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
4663 casts away constness. DIAG_FN gives the function to call if we
4664 need to issue a diagnostic; if it is NULL, no diagnostic will be
4665 issued. DESCRIPTION explains what operation is taking place. */
4668 check_for_casting_away_constness (tree src_type, tree dest_type,
4669 void (*diag_fn)(const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2),
4670 const char *description)
4672 if (diag_fn && casts_away_constness (src_type, dest_type))
4673 diag_fn ("%s from type %qT to type %qT casts away constness",
4674 description, src_type, dest_type);
4677 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
4678 (another pointer-to-member type in the same hierarchy) and return
4679 the converted expression. If ALLOW_INVERSE_P is permitted, a
4680 pointer-to-derived may be converted to pointer-to-base; otherwise,
4681 only the other direction is permitted. If C_CAST_P is true, this
4682 conversion is taking place as part of a C-style cast. */
4685 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
4688 if (TYPE_PTRMEM_P (type))
4692 if (TREE_CODE (expr) == PTRMEM_CST)
4693 expr = cplus_expand_constant (expr);
4694 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
4695 TYPE_PTRMEM_CLASS_TYPE (type),
4698 if (!integer_zerop (delta))
4699 expr = cp_build_binary_op (PLUS_EXPR,
4700 build_nop (ptrdiff_type_node, expr),
4702 return build_nop (type, expr);
4705 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4706 allow_inverse_p, c_cast_p);
4709 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
4710 a version of EXPR that has TREE_OVERFLOW and/or TREE_CONSTANT_OVERFLOW
4711 set iff they are set in ORIG. Otherwise, return EXPR unchanged. */
4714 ignore_overflows (tree expr, tree orig)
4716 if (TREE_CODE (expr) == INTEGER_CST
4717 && CONSTANT_CLASS_P (orig)
4718 && TREE_CODE (orig) != STRING_CST
4719 && (TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig)
4720 || TREE_CONSTANT_OVERFLOW (expr)
4721 != TREE_CONSTANT_OVERFLOW (orig)))
4723 if (!TREE_OVERFLOW (orig) && !TREE_CONSTANT_OVERFLOW (orig))
4724 /* Ensure constant sharing. */
4725 expr = build_int_cst_wide (TREE_TYPE (expr),
4726 TREE_INT_CST_LOW (expr),
4727 TREE_INT_CST_HIGH (expr));
4730 /* Avoid clobbering a shared constant. */
4731 expr = copy_node (expr);
4732 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
4733 TREE_CONSTANT_OVERFLOW (expr)
4734 = TREE_CONSTANT_OVERFLOW (orig);
4740 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
4741 this static_cast is being attempted as one of the possible casts
4742 allowed by a C-style cast. (In that case, accessibility of base
4743 classes is not considered, and it is OK to cast away
4744 constness.) Return the result of the cast. *VALID_P is set to
4745 indicate whether or not the cast was valid. */
4748 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
4754 void (*diag_fn)(const char*, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
4757 /* Assume the cast is valid. */
4760 intype = TREE_TYPE (expr);
4762 /* Save casted types in the function's used types hash table. */
4763 used_types_insert (type);
4765 /* Determine what to do when casting away constness. */
4768 /* C-style casts are allowed to cast away constness. With
4769 WARN_CAST_QUAL, we still want to issue a warning. */
4770 diag_fn = warn_cast_qual ? warning0 : NULL;
4775 /* A static_cast may not cast away constness. */
4777 desc = "static_cast";
4780 /* [expr.static.cast]
4782 An lvalue of type "cv1 B", where B is a class type, can be cast
4783 to type "reference to cv2 D", where D is a class derived (clause
4784 _class.derived_) from B, if a valid standard conversion from
4785 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4786 same cv-qualification as, or greater cv-qualification than, cv1,
4787 and B is not a virtual base class of D. */
4788 /* We check this case before checking the validity of "TYPE t =
4789 EXPR;" below because for this case:
4792 struct D : public B { D(const B&); };
4794 void f() { static_cast<const D&>(b); }
4796 we want to avoid constructing a new D. The standard is not
4797 completely clear about this issue, but our interpretation is
4798 consistent with other compilers. */
4799 if (TREE_CODE (type) == REFERENCE_TYPE
4800 && CLASS_TYPE_P (TREE_TYPE (type))
4801 && CLASS_TYPE_P (intype)
4802 && real_lvalue_p (expr)
4803 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4804 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4805 build_pointer_type (TYPE_MAIN_VARIANT
4806 (TREE_TYPE (type))))
4808 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
4812 /* There is a standard conversion from "D*" to "B*" even if "B"
4813 is ambiguous or inaccessible. If this is really a
4814 static_cast, then we check both for inaccessibility and
4815 ambiguity. However, if this is a static_cast being performed
4816 because the user wrote a C-style cast, then accessibility is
4818 base = lookup_base (TREE_TYPE (type), intype,
4819 c_cast_p ? ba_unique : ba_check,
4822 /* Convert from "B*" to "D*". This function will check that "B"
4823 is not a virtual base of "D". */
4824 expr = build_base_path (MINUS_EXPR, build_address (expr),
4825 base, /*nonnull=*/false);
4826 /* Convert the pointer to a reference -- but then remember that
4827 there are no expressions with reference type in C++. */
4828 return convert_from_reference (build_nop (type, expr));
4833 /* [expr.static.cast]
4835 An expression e can be explicitly converted to a type T using a
4836 static_cast of the form static_cast<T>(e) if the declaration T
4837 t(e);" is well-formed, for some invented temporary variable
4839 result = perform_direct_initialization_if_possible (type, expr,
4843 result = convert_from_reference (result);
4845 /* Ignore any integer overflow caused by the cast. */
4846 result = ignore_overflows (result, orig);
4848 /* [expr.static.cast]
4850 If T is a reference type, the result is an lvalue; otherwise,
4851 the result is an rvalue. */
4852 if (TREE_CODE (type) != REFERENCE_TYPE)
4853 result = rvalue (result);
4857 /* [expr.static.cast]
4859 Any expression can be explicitly converted to type cv void. */
4860 if (TREE_CODE (type) == VOID_TYPE)
4861 return convert_to_void (expr, /*implicit=*/NULL);
4863 /* [expr.static.cast]
4865 The inverse of any standard conversion sequence (clause _conv_),
4866 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4867 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4868 (_conv.bool_) conversions, can be performed explicitly using
4869 static_cast subject to the restriction that the explicit
4870 conversion does not cast away constness (_expr.const.cast_), and
4871 the following additional rules for specific cases: */
4872 /* For reference, the conversions not excluded are: integral
4873 promotions, floating point promotion, integral conversions,
4874 floating point conversions, floating-integral conversions,
4875 pointer conversions, and pointer to member conversions. */
4878 A value of integral _or enumeration_ type can be explicitly
4879 converted to an enumeration type. */
4880 /* The effect of all that is that any conversion between any two
4881 types which are integral, floating, or enumeration types can be
4883 if ((INTEGRAL_TYPE_P (type) || SCALAR_FLOAT_TYPE_P (type))
4884 && (INTEGRAL_TYPE_P (intype) || SCALAR_FLOAT_TYPE_P (intype)))
4886 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
4888 /* Ignore any integer overflow caused by the cast. */
4889 expr = ignore_overflows (expr, orig);
4893 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4894 && CLASS_TYPE_P (TREE_TYPE (type))
4895 && CLASS_TYPE_P (TREE_TYPE (intype))
4896 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4897 (TREE_TYPE (intype))),
4898 build_pointer_type (TYPE_MAIN_VARIANT
4899 (TREE_TYPE (type)))))
4904 check_for_casting_away_constness (intype, type, diag_fn, desc);
4905 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
4906 c_cast_p ? ba_unique : ba_check,
4908 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4911 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4912 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4919 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4920 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4922 if (TYPE_PTRMEM_P (type))
4924 t1 = (build_ptrmem_type
4926 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4927 t2 = (build_ptrmem_type
4929 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4936 if (can_convert (t1, t2))
4939 check_for_casting_away_constness (intype, type, diag_fn,
4941 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
4946 /* [expr.static.cast]
4948 An rvalue of type "pointer to cv void" can be explicitly
4949 converted to a pointer to object type. A value of type pointer
4950 to object converted to "pointer to cv void" and back to the
4951 original pointer type will have its original value. */
4952 if (TREE_CODE (intype) == POINTER_TYPE
4953 && VOID_TYPE_P (TREE_TYPE (intype))
4954 && TYPE_PTROB_P (type))
4957 check_for_casting_away_constness (intype, type, diag_fn, desc);
4958 return build_nop (type, expr);
4962 return error_mark_node;
4965 /* Return an expression representing static_cast<TYPE>(EXPR). */
4968 build_static_cast (tree type, tree expr)
4973 if (type == error_mark_node || expr == error_mark_node)
4974 return error_mark_node;
4976 if (processing_template_decl)
4978 expr = build_min (STATIC_CAST_EXPR, type, expr);
4979 /* We don't know if it will or will not have side effects. */
4980 TREE_SIDE_EFFECTS (expr) = 1;
4981 return convert_from_reference (expr);
4984 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4985 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4986 if (TREE_CODE (type) != REFERENCE_TYPE
4987 && TREE_CODE (expr) == NOP_EXPR
4988 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4989 expr = TREE_OPERAND (expr, 0);
4991 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p);
4995 error ("invalid static_cast from type %qT to type %qT",
4996 TREE_TYPE (expr), type);
4997 return error_mark_node;
5000 /* EXPR is an expression with member function or pointer-to-member
5001 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5002 not permitted by ISO C++, but we accept it in some modes. If we
5003 are not in one of those modes, issue a diagnostic. Return the
5004 converted expression. */
5007 convert_member_func_to_ptr (tree type, tree expr)
5012 intype = TREE_TYPE (expr);
5013 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
5014 || TREE_CODE (intype) == METHOD_TYPE);
5016 if (pedantic || warn_pmf2ptr)
5017 pedwarn ("converting from %qT to %qT", intype, type);
5019 if (TREE_CODE (intype) == METHOD_TYPE)
5020 expr = build_addr_func (expr);
5021 else if (TREE_CODE (expr) == PTRMEM_CST)
5022 expr = build_address (PTRMEM_CST_MEMBER (expr));
5025 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
5026 decl = build_address (decl);
5027 expr = get_member_function_from_ptrfunc (&decl, expr);
5030 return build_nop (type, expr);
5033 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5034 If C_CAST_P is true, this reinterpret cast is being done as part of
5035 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5036 indicate whether or not reinterpret_cast was valid. */
5039 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5044 /* Assume the cast is invalid. */
5048 if (type == error_mark_node || error_operand_p (expr))
5049 return error_mark_node;
5051 intype = TREE_TYPE (expr);
5053 /* Save casted types in the function's used types hash table. */
5054 used_types_insert (type);
5056 /* [expr.reinterpret.cast]
5057 An lvalue expression of type T1 can be cast to the type
5058 "reference to T2" if an expression of type "pointer to T1" can be
5059 explicitly converted to the type "pointer to T2" using a
5060 reinterpret_cast. */
5061 if (TREE_CODE (type) == REFERENCE_TYPE)
5063 if (! real_lvalue_p (expr))
5065 error ("invalid cast of an rvalue expression of type "
5068 return error_mark_node;
5071 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5072 "B" are related class types; the reinterpret_cast does not
5073 adjust the pointer. */
5074 if (TYPE_PTR_P (intype)
5075 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5076 COMPARE_BASE | COMPARE_DERIVED)))
5077 warning (0, "casting %qT to %qT does not dereference pointer",
5080 expr = build_unary_op (ADDR_EXPR, expr, 0);
5081 if (expr != error_mark_node)
5082 expr = build_reinterpret_cast_1
5083 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5085 if (expr != error_mark_node)
5086 expr = build_indirect_ref (expr, 0);
5090 /* As a G++ extension, we consider conversions from member
5091 functions, and pointers to member functions to
5092 pointer-to-function and pointer-to-void types. If
5093 -Wno-pmf-conversions has not been specified,
5094 convert_member_func_to_ptr will issue an error message. */
5095 if ((TYPE_PTRMEMFUNC_P (intype)
5096 || TREE_CODE (intype) == METHOD_TYPE)
5097 && TYPE_PTR_P (type)
5098 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5099 || VOID_TYPE_P (TREE_TYPE (type))))
5100 return convert_member_func_to_ptr (type, expr);
5102 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5103 array-to-pointer, and function-to-pointer conversions are
5105 expr = decay_conversion (expr);
5107 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5108 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5109 if (TREE_CODE (expr) == NOP_EXPR
5110 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5111 expr = TREE_OPERAND (expr, 0);
5113 if (error_operand_p (expr))
5114 return error_mark_node;
5116 intype = TREE_TYPE (expr);
5118 /* [expr.reinterpret.cast]
5119 A pointer can be converted to any integral type large enough to
5121 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5123 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5124 pedwarn ("cast from %qT to %qT loses precision",
5127 /* [expr.reinterpret.cast]
5128 A value of integral or enumeration type can be explicitly
5129 converted to a pointer. */
5130 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5133 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5134 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5135 return fold_if_not_in_template (build_nop (type, expr));
5136 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5137 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5142 check_for_casting_away_constness (intype, type, error,
5143 "reinterpret_cast");
5144 /* Warn about possible alignment problems. */
5145 if (STRICT_ALIGNMENT && warn_cast_align
5146 && !VOID_TYPE_P (type)
5147 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5148 && COMPLETE_TYPE_P (TREE_TYPE (type))
5149 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5150 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5151 warning (0, "cast from %qT to %qT increases required alignment of "
5155 /* We need to strip nops here, because the frontend likes to
5156 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5158 strict_aliasing_warning (intype, type, sexpr);
5160 return fold_if_not_in_template (build_nop (type, expr));
5162 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5163 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5166 /* Only issue a warning, as we have always supported this
5167 where possible, and it is necessary in some cases. DR 195
5168 addresses this issue, but as of 2004/10/26 is still in
5170 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5171 return fold_if_not_in_template (build_nop (type, expr));
5173 else if (TREE_CODE (type) == VECTOR_TYPE)
5174 return fold_if_not_in_template (convert_to_vector (type, expr));
5175 else if (TREE_CODE (intype) == VECTOR_TYPE)
5176 return fold_if_not_in_template (convert_to_integer (type, expr));
5181 error ("invalid cast from type %qT to type %qT", intype, type);
5182 return error_mark_node;
5185 return cp_convert (type, expr);
5189 build_reinterpret_cast (tree type, tree expr)
5191 if (type == error_mark_node || expr == error_mark_node)
5192 return error_mark_node;
5194 if (processing_template_decl)
5196 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5198 if (!TREE_SIDE_EFFECTS (t)
5199 && type_dependent_expression_p (expr))
5200 /* There might turn out to be side effects inside expr. */
5201 TREE_SIDE_EFFECTS (t) = 1;
5202 return convert_from_reference (t);
5205 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5209 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5210 return an appropriate expression. Otherwise, return
5211 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5212 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5213 performing a C-style cast, its value upon return will indicate
5214 whether or not the conversion succeeded. */
5217 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5221 tree reference_type;
5223 /* Callers are responsible for handling error_mark_node as a
5224 destination type. */
5225 gcc_assert (dst_type != error_mark_node);
5226 /* In a template, callers should be building syntactic
5227 representations of casts, not using this machinery. */
5228 gcc_assert (!processing_template_decl);
5230 /* Assume the conversion is invalid. */
5234 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5237 error ("invalid use of const_cast with type %qT, "
5238 "which is not a pointer, "
5239 "reference, nor a pointer-to-data-member type", dst_type);
5240 return error_mark_node;
5243 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5246 error ("invalid use of const_cast with type %qT, which is a pointer "
5247 "or reference to a function type", dst_type);
5248 return error_mark_node;
5251 /* Save casted types in the function's used types hash table. */
5252 used_types_insert (dst_type);
5254 src_type = TREE_TYPE (expr);
5255 /* Expressions do not really have reference types. */
5256 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5257 src_type = TREE_TYPE (src_type);
5259 /* [expr.const.cast]
5261 An lvalue of type T1 can be explicitly converted to an lvalue of
5262 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5263 types) if a pointer to T1 can be explicitly converted to the type
5264 pointer to T2 using a const_cast. */
5265 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5267 reference_type = dst_type;
5268 if (! real_lvalue_p (expr))
5271 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5272 src_type, dst_type);
5273 return error_mark_node;
5275 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5276 src_type = build_pointer_type (src_type);
5280 reference_type = NULL_TREE;
5281 /* If the destination type is not a reference type, the
5282 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5283 conversions are performed. */
5284 src_type = type_decays_to (src_type);
5285 if (src_type == error_mark_node)
5286 return error_mark_node;
5289 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5290 && comp_ptr_ttypes_const (dst_type, src_type))
5295 /* This cast is actually a C-style cast. Issue a warning if
5296 the user is making a potentially unsafe cast. */
5298 check_for_casting_away_constness (src_type, dst_type,
5304 expr = build_unary_op (ADDR_EXPR, expr, 0);
5305 expr = build_nop (reference_type, expr);
5306 return convert_from_reference (expr);
5310 expr = decay_conversion (expr);
5311 /* build_c_cast puts on a NOP_EXPR to make the result not an
5312 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5313 non-lvalue context. */
5314 if (TREE_CODE (expr) == NOP_EXPR
5315 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5316 expr = TREE_OPERAND (expr, 0);
5317 return build_nop (dst_type, expr);
5322 error ("invalid const_cast from type %qT to type %qT",
5323 src_type, dst_type);
5324 return error_mark_node;
5328 build_const_cast (tree type, tree expr)
5330 if (type == error_mark_node || error_operand_p (expr))
5331 return error_mark_node;
5333 if (processing_template_decl)
5335 tree t = build_min (CONST_CAST_EXPR, type, expr);
5337 if (!TREE_SIDE_EFFECTS (t)
5338 && type_dependent_expression_p (expr))
5339 /* There might turn out to be side effects inside expr. */
5340 TREE_SIDE_EFFECTS (t) = 1;
5341 return convert_from_reference (t);
5344 return build_const_cast_1 (type, expr, /*complain=*/true,
5348 /* Build an expression representing an explicit C-style cast to type
5349 TYPE of expression EXPR. */
5352 build_c_cast (tree type, tree expr)
5358 if (type == error_mark_node || error_operand_p (expr))
5359 return error_mark_node;
5361 if (processing_template_decl)
5363 tree t = build_min (CAST_EXPR, type,
5364 tree_cons (NULL_TREE, value, NULL_TREE));
5365 /* We don't know if it will or will not have side effects. */
5366 TREE_SIDE_EFFECTS (t) = 1;
5367 return convert_from_reference (t);
5370 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5371 'Class') should always be retained, because this information aids
5372 in method lookup. */
5373 if (objc_is_object_ptr (type)
5374 && objc_is_object_ptr (TREE_TYPE (expr)))
5375 return build_nop (type, expr);
5377 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5378 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5379 if (TREE_CODE (type) != REFERENCE_TYPE
5380 && TREE_CODE (value) == NOP_EXPR
5381 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5382 value = TREE_OPERAND (value, 0);
5384 if (TREE_CODE (type) == ARRAY_TYPE)
5386 /* Allow casting from T1* to T2[] because Cfront allows it.
5387 NIHCL uses it. It is not valid ISO C++ however. */
5388 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5390 pedwarn ("ISO C++ forbids casting to an array type %qT", type);
5391 type = build_pointer_type (TREE_TYPE (type));
5395 error ("ISO C++ forbids casting to an array type %qT", type);
5396 return error_mark_node;
5400 if (TREE_CODE (type) == FUNCTION_TYPE
5401 || TREE_CODE (type) == METHOD_TYPE)
5403 error ("invalid cast to function type %qT", type);
5404 return error_mark_node;
5407 /* A C-style cast can be a const_cast. */
5408 result = build_const_cast_1 (type, value, /*complain=*/false,
5413 /* Or a static cast. */
5414 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5416 /* Or a reinterpret_cast. */
5418 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5420 /* The static_cast or reinterpret_cast may be followed by a
5423 /* A valid cast may result in errors if, for example, a
5424 conversion to am ambiguous base class is required. */
5425 && !error_operand_p (result))
5429 /* Non-class rvalues always have cv-unqualified type. */
5430 if (!CLASS_TYPE_P (type))
5431 type = TYPE_MAIN_VARIANT (type);
5432 result_type = TREE_TYPE (result);
5433 if (!CLASS_TYPE_P (result_type))
5434 result_type = TYPE_MAIN_VARIANT (result_type);
5435 /* If the type of RESULT does not match TYPE, perform a
5436 const_cast to make it match. If the static_cast or
5437 reinterpret_cast succeeded, we will differ by at most
5438 cv-qualification, so the follow-on const_cast is guaranteed
5440 if (!same_type_p (non_reference (type), non_reference (result_type)))
5442 result = build_const_cast_1 (type, result, false, &valid_p);
5443 gcc_assert (valid_p);
5448 return error_mark_node;
5451 /* Build an assignment expression of lvalue LHS from value RHS.
5452 MODIFYCODE is the code for a binary operator that we use
5453 to combine the old value of LHS with RHS to get the new value.
5454 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5456 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5459 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5463 tree lhstype = TREE_TYPE (lhs);
5464 tree olhstype = lhstype;
5465 tree olhs = NULL_TREE;
5466 bool plain_assign = (modifycode == NOP_EXPR);
5468 /* Avoid duplicate error messages from operands that had errors. */
5469 if (lhs == error_mark_node || rhs == error_mark_node)
5470 return error_mark_node;
5472 /* Handle control structure constructs used as "lvalues". */
5473 switch (TREE_CODE (lhs))
5475 /* Handle --foo = 5; as these are valid constructs in C++. */
5476 case PREDECREMENT_EXPR:
5477 case PREINCREMENT_EXPR:
5478 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5479 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5480 stabilize_reference (TREE_OPERAND (lhs, 0)),
5481 TREE_OPERAND (lhs, 1));
5482 return build2 (COMPOUND_EXPR, lhstype,
5484 build_modify_expr (TREE_OPERAND (lhs, 0),
5487 /* Handle (a, b) used as an "lvalue". */
5489 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
5491 if (newrhs == error_mark_node)
5492 return error_mark_node;
5493 return build2 (COMPOUND_EXPR, lhstype,
5494 TREE_OPERAND (lhs, 0), newrhs);
5497 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5498 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5499 stabilize_reference (TREE_OPERAND (lhs, 0)),
5500 TREE_OPERAND (lhs, 1));
5501 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
5502 if (newrhs == error_mark_node)
5503 return error_mark_node;
5504 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5508 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
5509 when neither operand has side-effects. */
5510 if (!lvalue_or_else (lhs, lv_assign))
5511 return error_mark_node;
5513 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
5514 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
5516 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
5517 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
5519 TREE_OPERAND (lhs, 0),
5520 TREE_OPERAND (lhs, 1)),
5521 TREE_OPERAND (lhs, 0),
5522 TREE_OPERAND (lhs, 1));
5525 /* Handle (a ? b : c) used as an "lvalue". */
5528 /* Produce (a ? (b = rhs) : (c = rhs))
5529 except that the RHS goes through a save-expr
5530 so the code to compute it is only emitted once. */
5532 tree preeval = NULL_TREE;
5534 rhs = stabilize_expr (rhs, &preeval);
5536 /* Check this here to avoid odd errors when trying to convert
5537 a throw to the type of the COND_EXPR. */
5538 if (!lvalue_or_else (lhs, lv_assign))
5539 return error_mark_node;
5541 cond = build_conditional_expr
5542 (TREE_OPERAND (lhs, 0),
5543 build_modify_expr (TREE_OPERAND (lhs, 1),
5545 build_modify_expr (TREE_OPERAND (lhs, 2),
5548 if (cond == error_mark_node)
5550 /* Make sure the code to compute the rhs comes out
5551 before the split. */
5553 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5561 if (modifycode == INIT_EXPR)
5563 if (TREE_CODE (rhs) == CONSTRUCTOR)
5565 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5566 /* Call convert to generate an error; see PR 11063. */
5567 rhs = convert (lhstype, rhs);
5568 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
5569 TREE_SIDE_EFFECTS (result) = 1;
5572 else if (! IS_AGGR_TYPE (lhstype))
5573 /* Do the default thing. */;
5576 result = build_special_member_call (lhs, complete_ctor_identifier,
5577 build_tree_list (NULL_TREE, rhs),
5578 lhstype, LOOKUP_NORMAL);
5579 if (result == NULL_TREE)
5580 return error_mark_node;
5586 lhs = require_complete_type (lhs);
5587 if (lhs == error_mark_node)
5588 return error_mark_node;
5590 if (modifycode == NOP_EXPR)
5592 /* `operator=' is not an inheritable operator. */
5593 if (! IS_AGGR_TYPE (lhstype))
5594 /* Do the default thing. */;
5597 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5598 lhs, rhs, make_node (NOP_EXPR),
5599 /*overloaded_p=*/NULL);
5600 if (result == NULL_TREE)
5601 return error_mark_node;
5608 /* A binary op has been requested. Combine the old LHS
5609 value with the RHS producing the value we should actually
5610 store into the LHS. */
5612 gcc_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE));
5613 lhs = stabilize_reference (lhs);
5614 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
5615 if (newrhs == error_mark_node)
5617 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
5618 TREE_TYPE (lhs), TREE_TYPE (rhs));
5619 return error_mark_node;
5622 /* Now it looks like a plain assignment. */
5623 modifycode = NOP_EXPR;
5625 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
5626 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
5629 /* The left-hand side must be an lvalue. */
5630 if (!lvalue_or_else (lhs, lv_assign))
5631 return error_mark_node;
5633 /* Warn about modifying something that is `const'. Don't warn if
5634 this is initialization. */
5635 if (modifycode != INIT_EXPR
5636 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5637 /* Functions are not modifiable, even though they are
5639 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5640 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5641 /* If it's an aggregate and any field is const, then it is
5642 effectively const. */
5643 || (CLASS_TYPE_P (lhstype)
5644 && C_TYPE_FIELDS_READONLY (lhstype))))
5645 readonly_error (lhs, "assignment", 0);
5647 /* If storing into a structure or union member, it has probably been
5648 given type `int'. Compute the type that would go with the actual
5649 amount of storage the member occupies. */
5651 if (TREE_CODE (lhs) == COMPONENT_REF
5652 && (TREE_CODE (lhstype) == INTEGER_TYPE
5653 || TREE_CODE (lhstype) == REAL_TYPE
5654 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5656 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5658 /* If storing in a field that is in actuality a short or narrower
5659 than one, we must store in the field in its actual type. */
5661 if (lhstype != TREE_TYPE (lhs))
5663 /* Avoid warnings converting integral types back into enums for
5665 if (TREE_CODE (lhstype) == INTEGER_TYPE
5666 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5668 if (TREE_SIDE_EFFECTS (lhs))
5669 lhs = stabilize_reference (lhs);
5672 lhs = copy_node (lhs);
5673 TREE_TYPE (lhs) = lhstype;
5677 /* Convert new value to destination type. */
5679 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5683 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5684 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5686 error ("incompatible types in assignment of %qT to %qT",
5687 TREE_TYPE (rhs), lhstype);
5688 return error_mark_node;
5691 /* Allow array assignment in compiler-generated code. */
5692 if (! DECL_ARTIFICIAL (current_function_decl))
5693 pedwarn ("ISO C++ forbids assignment of arrays");
5695 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5696 ? 1 + (modifycode != INIT_EXPR): 0;
5697 return build_vec_init (lhs, NULL_TREE, newrhs,
5698 /*explicit_default_init_p=*/false,
5702 if (modifycode == INIT_EXPR)
5703 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5704 "initialization", NULL_TREE, 0);
5707 /* Avoid warnings on enum bit fields. */
5708 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5709 && TREE_CODE (lhstype) == INTEGER_TYPE)
5711 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5713 newrhs = convert_force (lhstype, newrhs, 0);
5716 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5718 if (TREE_CODE (newrhs) == CALL_EXPR
5719 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5720 newrhs = build_cplus_new (lhstype, newrhs);
5722 /* Can't initialize directly from a TARGET_EXPR, since that would
5723 cause the lhs to be constructed twice, and possibly result in
5724 accidental self-initialization. So we force the TARGET_EXPR to be
5725 expanded without a target. */
5726 if (TREE_CODE (newrhs) == TARGET_EXPR)
5727 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5728 TREE_OPERAND (newrhs, 0));
5731 if (newrhs == error_mark_node)
5732 return error_mark_node;
5734 if (c_dialect_objc () && flag_objc_gc)
5736 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
5742 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5743 lhstype, lhs, newrhs);
5745 TREE_SIDE_EFFECTS (result) = 1;
5747 TREE_NO_WARNING (result) = 1;
5749 /* If we got the LHS in a different type for storing in,
5750 convert the result back to the nominal type of LHS
5751 so that the value we return always has the same type
5752 as the LHS argument. */
5754 if (olhstype == TREE_TYPE (result))
5758 result = build2 (COMPOUND_EXPR, olhstype, result, olhs);
5759 TREE_NO_WARNING (result) = 1;
5762 return convert_for_assignment (olhstype, result, "assignment",
5767 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5769 if (processing_template_decl)
5770 return build_min_nt (MODOP_EXPR, lhs,
5771 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5773 if (modifycode != NOP_EXPR)
5775 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5776 make_node (modifycode),
5777 /*overloaded_p=*/NULL);
5780 TREE_NO_WARNING (rval) = 1;
5784 return build_modify_expr (lhs, modifycode, rhs);
5788 /* Get difference in deltas for different pointer to member function
5789 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5790 the conversion is invalid, the constant is zero. If
5791 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
5792 If C_CAST_P is true this conversion is taking place as part of a
5795 Note that the naming of FROM and TO is kind of backwards; the return
5796 value is what we add to a TO in order to get a FROM. They are named
5797 this way because we call this function to find out how to convert from
5798 a pointer to member of FROM to a pointer to member of TO. */
5801 get_delta_difference (tree from, tree to,
5802 bool allow_inverse_p,
5809 /* Assume no conversion is required. */
5810 result = integer_zero_node;
5811 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
5812 if (kind == bk_inaccessible || kind == bk_ambig)
5813 error (" in pointer to member function conversion");
5816 if (kind != bk_via_virtual)
5817 result = BINFO_OFFSET (binfo);
5820 tree virt_binfo = binfo_from_vbase (binfo);
5822 /* This is a reinterpret cast, we choose to do nothing. */
5823 if (allow_inverse_p)
5824 warning (0, "pointer to member cast via virtual base %qT",
5825 BINFO_TYPE (virt_binfo));
5827 error ("pointer to member conversion via virtual base %qT",
5828 BINFO_TYPE (virt_binfo));
5831 else if (same_type_ignoring_top_level_qualifiers_p (from, to))
5832 /* Pointer to member of incomplete class is permitted*/;
5833 else if (!allow_inverse_p)
5835 error_not_base_type (from, to);
5836 error (" in pointer to member conversion");
5840 binfo = lookup_base (from, to, c_cast_p ? ba_unique : ba_check, &kind);
5843 if (kind != bk_via_virtual)
5844 result = size_diffop (size_zero_node, BINFO_OFFSET (binfo));
5847 /* This is a reinterpret cast, we choose to do nothing. */
5848 tree virt_binfo = binfo_from_vbase (binfo);
5850 warning (0, "pointer to member cast via virtual base %qT",
5851 BINFO_TYPE (virt_binfo));
5856 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
5860 /* Return a constructor for the pointer-to-member-function TYPE using
5861 the other components as specified. */
5864 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5869 VEC(constructor_elt, gc) *v;
5871 /* Pull the FIELD_DECLs out of the type. */
5872 pfn_field = TYPE_FIELDS (type);
5873 delta_field = TREE_CHAIN (pfn_field);
5875 /* Make sure DELTA has the type we want. */
5876 delta = convert_and_check (delta_type_node, delta);
5878 /* Finish creating the initializer. */
5879 v = VEC_alloc(constructor_elt, gc, 2);
5880 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
5881 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
5882 u = build_constructor (type, v);
5883 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
5884 TREE_INVARIANT (u) = TREE_INVARIANT (pfn) & TREE_INVARIANT (delta);
5885 TREE_STATIC (u) = (TREE_CONSTANT (u)
5886 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5888 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5893 /* Build a constructor for a pointer to member function. It can be
5894 used to initialize global variables, local variable, or used
5895 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5898 If FORCE is nonzero, then force this conversion, even if
5899 we would rather not do it. Usually set when using an explicit
5900 cast. A C-style cast is being processed iff C_CAST_P is true.
5902 Return error_mark_node, if something goes wrong. */
5905 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
5911 if (error_operand_p (pfn))
5912 return error_mark_node;
5914 pfn_type = TREE_TYPE (pfn);
5915 to_type = build_ptrmemfunc_type (type);
5917 /* Handle multiple conversions of pointer to member functions. */
5918 if (TYPE_PTRMEMFUNC_P (pfn_type))
5920 tree delta = NULL_TREE;
5921 tree npfn = NULL_TREE;
5925 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
5926 error ("invalid conversion to type %qT from type %qT",
5929 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5930 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5934 /* We don't have to do any conversion to convert a
5935 pointer-to-member to its own type. But, we don't want to
5936 just return a PTRMEM_CST if there's an explicit cast; that
5937 cast should make the expression an invalid template argument. */
5938 if (TREE_CODE (pfn) != PTRMEM_CST)
5940 if (same_type_p (to_type, pfn_type))
5942 else if (integer_zerop (n))
5943 return build_reinterpret_cast (to_type, pfn);
5946 if (TREE_SIDE_EFFECTS (pfn))
5947 pfn = save_expr (pfn);
5949 /* Obtain the function pointer and the current DELTA. */
5950 if (TREE_CODE (pfn) == PTRMEM_CST)
5951 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
5954 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
5955 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
5958 /* Just adjust the DELTA field. */
5959 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5960 (TREE_TYPE (delta), ptrdiff_type_node));
5961 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
5962 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
5963 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
5964 return build_ptrmemfunc1 (to_type, delta, npfn);
5967 /* Handle null pointer to member function conversions. */
5968 if (integer_zerop (pfn))
5970 pfn = build_c_cast (type, integer_zero_node);
5971 return build_ptrmemfunc1 (to_type,
5976 if (type_unknown_p (pfn))
5977 return instantiate_type (type, pfn, tf_warning_or_error);
5979 fn = TREE_OPERAND (pfn, 0);
5980 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
5981 /* In a template, we will have preserved the
5983 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
5984 return make_ptrmem_cst (to_type, fn);
5987 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
5990 ??? There is no consistency as to the types returned for the above
5991 values. Some code acts as if it were a sizetype and some as if it were
5992 integer_type_node. */
5995 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
5997 tree type = TREE_TYPE (cst);
5998 tree fn = PTRMEM_CST_MEMBER (cst);
5999 tree ptr_class, fn_class;
6001 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6003 /* The class that the function belongs to. */
6004 fn_class = DECL_CONTEXT (fn);
6006 /* The class that we're creating a pointer to member of. */
6007 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
6009 /* First, calculate the adjustment to the function's class. */
6010 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
6013 if (!DECL_VIRTUAL_P (fn))
6014 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
6017 /* If we're dealing with a virtual function, we have to adjust 'this'
6018 again, to point to the base which provides the vtable entry for
6019 fn; the call will do the opposite adjustment. */
6020 tree orig_class = DECL_CONTEXT (fn);
6021 tree binfo = binfo_or_else (orig_class, fn_class);
6022 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6023 *delta, BINFO_OFFSET (binfo));
6024 *delta = fold_if_not_in_template (*delta);
6026 /* We set PFN to the vtable offset at which the function can be
6027 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6028 case delta is shifted left, and then incremented). */
6029 *pfn = DECL_VINDEX (fn);
6030 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
6031 TYPE_SIZE_UNIT (vtable_entry_type));
6032 *pfn = fold_if_not_in_template (*pfn);
6034 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
6036 case ptrmemfunc_vbit_in_pfn:
6037 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6039 *pfn = fold_if_not_in_template (*pfn);
6042 case ptrmemfunc_vbit_in_delta:
6043 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6044 *delta, integer_one_node);
6045 *delta = fold_if_not_in_template (*delta);
6046 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6047 *delta, integer_one_node);
6048 *delta = fold_if_not_in_template (*delta);
6055 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6056 *pfn = fold_if_not_in_template (*pfn);
6060 /* Return an expression for PFN from the pointer-to-member function
6064 pfn_from_ptrmemfunc (tree t)
6066 if (TREE_CODE (t) == PTRMEM_CST)
6071 expand_ptrmemfunc_cst (t, &delta, &pfn);
6076 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6079 /* Convert value RHS to type TYPE as preparation for an assignment to
6080 an lvalue of type TYPE. ERRTYPE is a string to use in error
6081 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6082 are doing the conversion in order to pass the PARMNUMth argument of
6086 convert_for_assignment (tree type, tree rhs,
6087 const char *errtype, tree fndecl, int parmnum)
6090 enum tree_code coder;
6092 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6093 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6094 rhs = TREE_OPERAND (rhs, 0);
6096 rhstype = TREE_TYPE (rhs);
6097 coder = TREE_CODE (rhstype);
6099 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6100 && vector_types_convertible_p (type, rhstype))
6101 return convert (type, rhs);
6103 if (rhs == error_mark_node || rhstype == error_mark_node)
6104 return error_mark_node;
6105 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6106 return error_mark_node;
6108 /* The RHS of an assignment cannot have void type. */
6109 if (coder == VOID_TYPE)
6111 error ("void value not ignored as it ought to be");
6112 return error_mark_node;
6115 /* Simplify the RHS if possible. */
6116 if (TREE_CODE (rhs) == CONST_DECL)
6117 rhs = DECL_INITIAL (rhs);
6119 if (c_dialect_objc ())
6122 tree rname = fndecl;
6124 if (!strcmp (errtype, "assignment"))
6126 else if (!strcmp (errtype, "initialization"))
6130 tree selector = objc_message_selector ();
6134 if (selector && parmno > 1)
6141 if (objc_compare_types (type, rhstype, parmno, rname))
6142 return convert (type, rhs);
6147 The expression is implicitly converted (clause _conv_) to the
6148 cv-unqualified type of the left operand.
6150 We allow bad conversions here because by the time we get to this point
6151 we are committed to doing the conversion. If we end up doing a bad
6152 conversion, convert_like will complain. */
6153 if (!can_convert_arg_bad (type, rhstype, rhs))
6155 /* When -Wno-pmf-conversions is use, we just silently allow
6156 conversions from pointers-to-members to plain pointers. If
6157 the conversion doesn't work, cp_convert will complain. */
6159 && TYPE_PTR_P (type)
6160 && TYPE_PTRMEMFUNC_P (rhstype))
6161 rhs = cp_convert (strip_top_quals (type), rhs);
6164 /* If the right-hand side has unknown type, then it is an
6165 overloaded function. Call instantiate_type to get error
6167 if (rhstype == unknown_type_node)
6168 instantiate_type (type, rhs, tf_warning_or_error);
6170 error ("cannot convert %qT to %qT for argument %qP to %qD",
6171 rhstype, type, parmnum, fndecl);
6173 error ("cannot convert %qT to %qT in %s", rhstype, type, errtype);
6174 return error_mark_node;
6177 if (warn_missing_format_attribute)
6179 const enum tree_code codel = TREE_CODE (type);
6180 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6182 && check_missing_format_attribute (type, rhstype))
6183 warning (OPT_Wmissing_format_attribute,
6184 "%s might be a candidate for a format attribute",
6188 return perform_implicit_conversion (strip_top_quals (type), rhs);
6191 /* Convert RHS to be of type TYPE.
6192 If EXP is nonzero, it is the target of the initialization.
6193 ERRTYPE is a string to use in error messages.
6195 Two major differences between the behavior of
6196 `convert_for_assignment' and `convert_for_initialization'
6197 are that references are bashed in the former, while
6198 copied in the latter, and aggregates are assigned in
6199 the former (operator=) while initialized in the
6202 If using constructor make sure no conversion operator exists, if one does
6203 exist, an ambiguity exists.
6205 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6208 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6209 const char *errtype, tree fndecl, int parmnum)
6211 enum tree_code codel = TREE_CODE (type);
6213 enum tree_code coder;
6215 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6216 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6217 if (TREE_CODE (rhs) == NOP_EXPR
6218 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6219 && codel != REFERENCE_TYPE)
6220 rhs = TREE_OPERAND (rhs, 0);
6222 if (rhs == error_mark_node
6223 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6224 return error_mark_node;
6226 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6227 && TREE_CODE (type) != ARRAY_TYPE
6228 && (TREE_CODE (type) != REFERENCE_TYPE
6229 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6230 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6231 && (TREE_CODE (type) != REFERENCE_TYPE
6232 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6233 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6234 rhs = decay_conversion (rhs);
6236 rhstype = TREE_TYPE (rhs);
6237 coder = TREE_CODE (rhstype);
6239 if (coder == ERROR_MARK)
6240 return error_mark_node;
6242 /* We accept references to incomplete types, so we can
6243 return here before checking if RHS is of complete type. */
6245 if (codel == REFERENCE_TYPE)
6247 /* This should eventually happen in convert_arguments. */
6248 int savew = 0, savee = 0;
6251 savew = warningcount, savee = errorcount;
6252 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6256 if (warningcount > savew)
6257 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6258 else if (errorcount > savee)
6259 error ("in passing argument %P of %q+D", parmnum, fndecl);
6265 exp = require_complete_type (exp);
6266 if (exp == error_mark_node)
6267 return error_mark_node;
6269 rhstype = non_reference (rhstype);
6271 type = complete_type (type);
6273 if (IS_AGGR_TYPE (type))
6274 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6276 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
6279 /* If RETVAL is the address of, or a reference to, a local variable or
6280 temporary give an appropriate warning. */
6283 maybe_warn_about_returning_address_of_local (tree retval)
6285 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6286 tree whats_returned = retval;
6290 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6291 whats_returned = TREE_OPERAND (whats_returned, 1);
6292 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
6293 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
6294 || TREE_CODE (whats_returned) == NOP_EXPR)
6295 whats_returned = TREE_OPERAND (whats_returned, 0);
6300 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6302 whats_returned = TREE_OPERAND (whats_returned, 0);
6304 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6306 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6307 || TREE_CODE (whats_returned) == TARGET_EXPR)
6309 warning (0, "returning reference to temporary");
6312 if (TREE_CODE (whats_returned) == VAR_DECL
6313 && DECL_NAME (whats_returned)
6314 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6316 warning (0, "reference to non-lvalue returned");
6321 if (DECL_P (whats_returned)
6322 && DECL_NAME (whats_returned)
6323 && DECL_FUNCTION_SCOPE_P (whats_returned)
6324 && !(TREE_STATIC (whats_returned)
6325 || TREE_PUBLIC (whats_returned)))
6327 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6328 warning (0, "reference to local variable %q+D returned",
6331 warning (0, "address of local variable %q+D returned",
6337 /* Check that returning RETVAL from the current function is valid.
6338 Return an expression explicitly showing all conversions required to
6339 change RETVAL into the function return type, and to assign it to
6340 the DECL_RESULT for the function. Set *NO_WARNING to true if
6341 code reaches end of non-void function warning shouldn't be issued
6342 on this RETURN_EXPR. */
6345 check_return_expr (tree retval, bool *no_warning)
6348 /* The type actually returned by the function, after any
6351 int fn_returns_value_p;
6353 *no_warning = false;
6355 /* A `volatile' function is one that isn't supposed to return, ever.
6356 (This is a G++ extension, used to get better code for functions
6357 that call the `volatile' function.) */
6358 if (TREE_THIS_VOLATILE (current_function_decl))
6359 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6361 /* Check for various simple errors. */
6362 if (DECL_DESTRUCTOR_P (current_function_decl))
6365 error ("returning a value from a destructor");
6368 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6370 if (in_function_try_handler)
6371 /* If a return statement appears in a handler of the
6372 function-try-block of a constructor, the program is ill-formed. */
6373 error ("cannot return from a handler of a function-try-block of a constructor");
6375 /* You can't return a value from a constructor. */
6376 error ("returning a value from a constructor");
6380 if (processing_template_decl)
6382 current_function_returns_value = 1;
6386 /* When no explicit return-value is given in a function with a named
6387 return value, the named return value is used. */
6388 result = DECL_RESULT (current_function_decl);
6389 valtype = TREE_TYPE (result);
6390 gcc_assert (valtype != NULL_TREE);
6391 fn_returns_value_p = !VOID_TYPE_P (valtype);
6392 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6395 /* Check for a return statement with no return value in a function
6396 that's supposed to return a value. */
6397 if (!retval && fn_returns_value_p)
6399 pedwarn ("return-statement with no value, in function returning %qT",
6401 /* Clear this, so finish_function won't say that we reach the
6402 end of a non-void function (which we don't, we gave a
6404 current_function_returns_null = 0;
6405 /* And signal caller that TREE_NO_WARNING should be set on the
6406 RETURN_EXPR to avoid control reaches end of non-void function
6407 warnings in tree-cfg.c. */
6410 /* Check for a return statement with a value in a function that
6411 isn't supposed to return a value. */
6412 else if (retval && !fn_returns_value_p)
6414 if (VOID_TYPE_P (TREE_TYPE (retval)))
6415 /* You can return a `void' value from a function of `void'
6416 type. In that case, we have to evaluate the expression for
6417 its side-effects. */
6418 finish_expr_stmt (retval);
6420 pedwarn ("return-statement with a value, in function "
6421 "returning 'void'");
6423 current_function_returns_null = 1;
6425 /* There's really no value to return, after all. */
6429 /* Remember that this function can sometimes return without a
6431 current_function_returns_null = 1;
6433 /* Remember that this function did return a value. */
6434 current_function_returns_value = 1;
6436 /* Check for erroneous operands -- but after giving ourselves a
6437 chance to provide an error about returning a value from a void
6439 if (error_operand_p (retval))
6441 current_function_return_value = error_mark_node;
6442 return error_mark_node;
6445 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
6446 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
6447 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
6448 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
6450 && null_ptr_cst_p (retval))
6451 warning (0, "%<operator new%> must not return NULL unless it is "
6452 "declared %<throw()%> (or -fcheck-new is in effect)");
6454 /* Effective C++ rule 15. See also start_function. */
6456 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
6460 /* The function return type must be a reference to the current
6462 if (TREE_CODE (valtype) == REFERENCE_TYPE
6463 && same_type_ignoring_top_level_qualifiers_p
6464 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
6466 /* Returning '*this' is obviously OK. */
6467 if (retval == current_class_ref)
6469 /* If we are calling a function whose return type is the same of
6470 the current class reference, it is ok. */
6471 else if (TREE_CODE (retval) == INDIRECT_REF
6472 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
6477 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
6480 /* The fabled Named Return Value optimization, as per [class.copy]/15:
6482 [...] For a function with a class return type, if the expression
6483 in the return statement is the name of a local object, and the cv-
6484 unqualified type of the local object is the same as the function
6485 return type, an implementation is permitted to omit creating the tem-
6486 porary object to hold the function return value [...]
6488 So, if this is a value-returning function that always returns the same
6489 local variable, remember it.
6491 It might be nice to be more flexible, and choose the first suitable
6492 variable even if the function sometimes returns something else, but
6493 then we run the risk of clobbering the variable we chose if the other
6494 returned expression uses the chosen variable somehow. And people expect
6495 this restriction, anyway. (jason 2000-11-19)
6497 See finish_function and finalize_nrv for the rest of this optimization. */
6499 if (fn_returns_value_p && flag_elide_constructors)
6501 if (retval != NULL_TREE
6502 && (current_function_return_value == NULL_TREE
6503 || current_function_return_value == retval)
6504 && TREE_CODE (retval) == VAR_DECL
6505 && DECL_CONTEXT (retval) == current_function_decl
6506 && ! TREE_STATIC (retval)
6507 && (DECL_ALIGN (retval)
6508 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6509 && same_type_p ((TYPE_MAIN_VARIANT
6510 (TREE_TYPE (retval))),
6512 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
6513 current_function_return_value = retval;
6515 current_function_return_value = error_mark_node;
6518 /* We don't need to do any conversions when there's nothing being
6523 /* Do any required conversions. */
6524 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6525 /* No conversions are required. */
6529 /* The type the function is declared to return. */
6530 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6532 /* The functype's return type will have been set to void, if it
6533 was an incomplete type. Just treat this as 'return;' */
6534 if (VOID_TYPE_P (functype))
6535 return error_mark_node;
6537 /* First convert the value to the function's return type, then
6538 to the type of return value's location to handle the
6539 case that functype is smaller than the valtype. */
6540 retval = convert_for_initialization
6541 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
6542 "return", NULL_TREE, 0);
6543 retval = convert (valtype, retval);
6545 /* If the conversion failed, treat this just like `return;'. */
6546 if (retval == error_mark_node)
6548 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6549 else if (! current_function_returns_struct
6550 && TREE_CODE (retval) == TARGET_EXPR
6551 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6552 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6553 TREE_OPERAND (retval, 0));
6555 maybe_warn_about_returning_address_of_local (retval);
6558 /* Actually copy the value returned into the appropriate location. */
6559 if (retval && retval != result)
6560 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
6566 /* Returns nonzero if the pointer-type FROM can be converted to the
6567 pointer-type TO via a qualification conversion. If CONSTP is -1,
6568 then we return nonzero if the pointers are similar, and the
6569 cv-qualification signature of FROM is a proper subset of that of TO.
6571 If CONSTP is positive, then all outer pointers have been
6575 comp_ptr_ttypes_real (tree to, tree from, int constp)
6577 bool to_more_cv_qualified = false;
6579 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6581 if (TREE_CODE (to) != TREE_CODE (from))
6584 if (TREE_CODE (from) == OFFSET_TYPE
6585 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
6586 TYPE_OFFSET_BASETYPE (to)))
6589 /* Const and volatile mean something different for function types,
6590 so the usual checks are not appropriate. */
6591 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6593 /* In Objective-C++, some types may have been 'volatilized' by
6594 the compiler for EH; when comparing them here, the volatile
6595 qualification must be ignored. */
6596 bool objc_quals_match = objc_type_quals_match (to, from);
6598 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
6601 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
6605 to_more_cv_qualified = true;
6609 constp &= TYPE_READONLY (to);
6612 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
6613 return ((constp >= 0 || to_more_cv_qualified)
6614 && same_type_ignoring_top_level_qualifiers_p (to, from));
6618 /* When comparing, say, char ** to char const **, this function takes
6619 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6620 types to this function. */
6623 comp_ptr_ttypes (tree to, tree from)
6625 return comp_ptr_ttypes_real (to, from, 1);
6628 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6629 type or inheritance-related types, regardless of cv-quals. */
6632 ptr_reasonably_similar (tree to, tree from)
6634 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6636 /* Any target type is similar enough to void. */
6637 if (TREE_CODE (to) == VOID_TYPE
6638 || TREE_CODE (from) == VOID_TYPE)
6641 if (TREE_CODE (to) != TREE_CODE (from))
6644 if (TREE_CODE (from) == OFFSET_TYPE
6645 && comptypes (TYPE_OFFSET_BASETYPE (to),
6646 TYPE_OFFSET_BASETYPE (from),
6647 COMPARE_BASE | COMPARE_DERIVED))
6650 if (TREE_CODE (to) == VECTOR_TYPE
6651 && vector_types_convertible_p (to, from))
6654 if (TREE_CODE (to) == INTEGER_TYPE
6655 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6658 if (TREE_CODE (to) == FUNCTION_TYPE)
6661 if (TREE_CODE (to) != POINTER_TYPE)
6663 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6664 COMPARE_BASE | COMPARE_DERIVED);
6668 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
6669 pointer-to-member types) are the same, ignoring cv-qualification at
6673 comp_ptr_ttypes_const (tree to, tree from)
6675 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6677 if (TREE_CODE (to) != TREE_CODE (from))
6680 if (TREE_CODE (from) == OFFSET_TYPE
6681 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6682 TYPE_OFFSET_BASETYPE (to)))
6685 if (TREE_CODE (to) != POINTER_TYPE)
6686 return same_type_ignoring_top_level_qualifiers_p (to, from);
6690 /* Returns the type qualifiers for this type, including the qualifiers on the
6691 elements for an array type. */
6694 cp_type_quals (tree type)
6696 type = strip_array_types (type);
6697 if (type == error_mark_node)
6698 return TYPE_UNQUALIFIED;
6699 return TYPE_QUALS (type);
6702 /* Returns nonzero if the TYPE contains a mutable member. */
6705 cp_has_mutable_p (tree type)
6707 type = strip_array_types (type);
6709 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6712 /* Apply the TYPE_QUALS to the new DECL. */
6714 cp_apply_type_quals_to_decl (int type_quals, tree decl)
6716 tree type = TREE_TYPE (decl);
6718 if (type == error_mark_node)
6721 if (TREE_CODE (type) == FUNCTION_TYPE
6722 && type_quals != TYPE_UNQUALIFIED)
6724 /* This was an error in C++98 (cv-qualifiers cannot be added to
6725 a function type), but DR 295 makes the code well-formed by
6726 dropping the extra qualifiers. */
6729 tree bad_type = build_qualified_type (type, type_quals);
6730 pedwarn ("ignoring %qV qualifiers added to function type %qT",
6734 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
6738 /* Avoid setting TREE_READONLY incorrectly. */
6739 if (/* If the object has a constructor, the constructor may modify
6741 TYPE_NEEDS_CONSTRUCTING (type)
6742 /* If the type isn't complete, we don't know yet if it will need
6744 || !COMPLETE_TYPE_P (type)
6745 /* If the type has a mutable component, that component might be
6747 || TYPE_HAS_MUTABLE_P (type))
6748 type_quals &= ~TYPE_QUAL_CONST;
6750 c_apply_type_quals_to_decl (type_quals, decl);
6753 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6754 exemplar types such that casting T1 to T2 is casting away constness
6755 if and only if there is no implicit conversion from T1 to T2. */
6758 casts_away_constness_r (tree *t1, tree *t2)
6763 /* [expr.const.cast]
6765 For multi-level pointer to members and multi-level mixed pointers
6766 and pointers to members (conv.qual), the "member" aspect of a
6767 pointer to member level is ignored when determining if a const
6768 cv-qualifier has been cast away. */
6769 /* [expr.const.cast]
6771 For two pointer types:
6773 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6774 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6777 casting from X1 to X2 casts away constness if, for a non-pointer
6778 type T there does not exist an implicit conversion (clause
6781 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6785 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6786 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
6787 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
6789 *t1 = cp_build_qualified_type (void_type_node,
6790 cp_type_quals (*t1));
6791 *t2 = cp_build_qualified_type (void_type_node,
6792 cp_type_quals (*t2));
6796 quals1 = cp_type_quals (*t1);
6797 quals2 = cp_type_quals (*t2);
6799 if (TYPE_PTRMEM_P (*t1))
6800 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
6802 *t1 = TREE_TYPE (*t1);
6803 if (TYPE_PTRMEM_P (*t2))
6804 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
6806 *t2 = TREE_TYPE (*t2);
6808 casts_away_constness_r (t1, t2);
6809 *t1 = build_pointer_type (*t1);
6810 *t2 = build_pointer_type (*t2);
6811 *t1 = cp_build_qualified_type (*t1, quals1);
6812 *t2 = cp_build_qualified_type (*t2, quals2);
6815 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6819 casts_away_constness (tree t1, tree t2)
6821 if (TREE_CODE (t2) == REFERENCE_TYPE)
6823 /* [expr.const.cast]
6825 Casting from an lvalue of type T1 to an lvalue of type T2
6826 using a reference cast casts away constness if a cast from an
6827 rvalue of type "pointer to T1" to the type "pointer to T2"
6828 casts away constness. */
6829 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6830 return casts_away_constness (build_pointer_type (t1),
6831 build_pointer_type (TREE_TYPE (t2)));
6834 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6835 /* [expr.const.cast]
6837 Casting from an rvalue of type "pointer to data member of X
6838 of type T1" to the type "pointer to data member of Y of type
6839 T2" casts away constness if a cast from an rvalue of type
6840 "pointer to T1" to the type "pointer to T2" casts away
6842 return casts_away_constness
6843 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6844 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6846 /* Casting away constness is only something that makes sense for
6847 pointer or reference types. */
6848 if (TREE_CODE (t1) != POINTER_TYPE
6849 || TREE_CODE (t2) != POINTER_TYPE)
6852 /* Top-level qualifiers don't matter. */
6853 t1 = TYPE_MAIN_VARIANT (t1);
6854 t2 = TYPE_MAIN_VARIANT (t2);
6855 casts_away_constness_r (&t1, &t2);
6856 if (!can_convert (t2, t1))
6862 /* If T is a REFERENCE_TYPE return the type to which T refers.
6863 Otherwise, return T itself. */
6866 non_reference (tree t)
6868 if (TREE_CODE (t) == REFERENCE_TYPE)
6874 /* Return nonzero if REF is an lvalue valid for this language;
6875 otherwise, print an error message and return zero. USE says
6876 how the lvalue is being used and so selects the error message. */
6879 lvalue_or_else (tree ref, enum lvalue_use use)
6881 int win = lvalue_p (ref);