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 convert_for_assignment (tree, tree, const char *, tree, int);
47 static tree cp_pointer_int_sum (enum tree_code, tree, tree);
48 static tree rationalize_conditional_expr (enum tree_code, tree);
49 static int comp_ptr_ttypes_real (tree, tree, int);
50 static bool comp_except_types (tree, tree, bool);
51 static bool comp_array_types (tree, tree, bool);
52 static tree common_base_type (tree, tree);
53 static tree pointer_diff (tree, tree, tree);
54 static tree get_delta_difference (tree, tree, bool, bool);
55 static void casts_away_constness_r (tree *, tree *);
56 static bool casts_away_constness (tree, tree);
57 static void maybe_warn_about_returning_address_of_local (tree);
58 static tree lookup_destructor (tree, tree, tree);
59 static tree convert_arguments (tree, tree, tree, int);
61 /* Do `exp = require_complete_type (exp);' to make sure exp
62 does not have an incomplete type. (That includes void types.)
63 Returns the error_mark_node if the VALUE does not have
64 complete type when this function returns. */
67 require_complete_type (tree value)
71 if (processing_template_decl || value == error_mark_node)
74 if (TREE_CODE (value) == OVERLOAD)
75 type = unknown_type_node;
77 type = TREE_TYPE (value);
79 if (type == error_mark_node)
80 return error_mark_node;
82 /* First, detect a valid value with a complete type. */
83 if (COMPLETE_TYPE_P (type))
86 if (complete_type_or_else (type, value))
89 return error_mark_node;
92 /* Try to complete TYPE, if it is incomplete. For example, if TYPE is
93 a template instantiation, do the instantiation. Returns TYPE,
94 whether or not it could be completed, unless something goes
95 horribly wrong, in which case the error_mark_node is returned. */
98 complete_type (tree type)
100 if (type == NULL_TREE)
101 /* Rather than crash, we return something sure to cause an error
103 return error_mark_node;
105 if (type == error_mark_node || COMPLETE_TYPE_P (type))
107 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
109 tree t = complete_type (TREE_TYPE (type));
110 unsigned int needs_constructing, has_nontrivial_dtor;
111 if (COMPLETE_TYPE_P (t) && !dependent_type_p (type))
114 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
116 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
117 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
119 TYPE_NEEDS_CONSTRUCTING (t) = needs_constructing;
120 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = has_nontrivial_dtor;
123 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
124 instantiate_class_template (TYPE_MAIN_VARIANT (type));
129 /* Like complete_type, but issue an error if the TYPE cannot be completed.
130 VALUE is used for informative diagnostics.
131 Returns NULL_TREE if the type cannot be made complete. */
134 complete_type_or_else (tree type, tree value)
136 type = complete_type (type);
137 if (type == error_mark_node)
138 /* We already issued an error. */
140 else if (!COMPLETE_TYPE_P (type))
142 cxx_incomplete_type_diagnostic (value, type, 0);
149 /* Return truthvalue of whether type of EXP is instantiated. */
152 type_unknown_p (tree exp)
154 return (TREE_CODE (exp) == TREE_LIST
155 || TREE_TYPE (exp) == unknown_type_node);
159 /* Return the common type of two parameter lists.
160 We assume that comptypes has already been done and returned 1;
161 if that isn't so, this may crash.
163 As an optimization, free the space we allocate if the parameter
164 lists are already common. */
167 commonparms (tree p1, tree p2)
169 tree oldargs = p1, newargs, n;
173 len = list_length (p1);
174 newargs = tree_last (p1);
176 if (newargs == void_list_node)
185 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
190 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
192 if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
194 TREE_PURPOSE (n) = TREE_PURPOSE (p1);
197 else if (! TREE_PURPOSE (p1))
199 if (TREE_PURPOSE (p2))
201 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
207 if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
209 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
211 if (TREE_VALUE (p1) != TREE_VALUE (p2))
214 TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2));
217 TREE_VALUE (n) = TREE_VALUE (p1);
225 /* Given a type, perhaps copied for a typedef,
226 find the "original" version of it. */
228 original_type (tree t)
230 while (TYPE_NAME (t) != NULL_TREE)
232 tree x = TYPE_NAME (t);
233 if (TREE_CODE (x) != TYPE_DECL)
235 x = DECL_ORIGINAL_TYPE (x);
243 /* T1 and T2 are arithmetic or enumeration types. Return the type
244 that will result from the "usual arithmetic conversions" on T1 and
245 T2 as described in [expr]. */
248 type_after_usual_arithmetic_conversions (tree t1, tree t2)
250 enum tree_code code1 = TREE_CODE (t1);
251 enum tree_code code2 = TREE_CODE (t2);
254 /* FIXME: Attributes. */
255 gcc_assert (ARITHMETIC_TYPE_P (t1)
256 || TREE_CODE (t1) == COMPLEX_TYPE
257 || TREE_CODE (t1) == VECTOR_TYPE
258 || TREE_CODE (t1) == ENUMERAL_TYPE);
259 gcc_assert (ARITHMETIC_TYPE_P (t2)
260 || TREE_CODE (t2) == COMPLEX_TYPE
261 || TREE_CODE (t1) == VECTOR_TYPE
262 || TREE_CODE (t2) == ENUMERAL_TYPE);
264 /* In what follows, we slightly generalize the rules given in [expr] so
265 as to deal with `long long' and `complex'. First, merge the
267 attributes = (*targetm.merge_type_attributes) (t1, t2);
269 /* If one type is complex, form the common type of the non-complex
270 components, then make that complex. Use T1 or T2 if it is the
272 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
274 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
275 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
277 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
279 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
280 return build_type_attribute_variant (t1, attributes);
281 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
282 return build_type_attribute_variant (t2, attributes);
284 return build_type_attribute_variant (build_complex_type (subtype),
288 if (code1 == VECTOR_TYPE)
290 /* When we get here we should have two vectors of the same size.
291 Just prefer the unsigned one if present. */
292 if (TYPE_UNSIGNED (t1))
293 return build_type_attribute_variant (t1, attributes);
295 return build_type_attribute_variant (t2, attributes);
298 /* If only one is real, use it as the result. */
299 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
300 return build_type_attribute_variant (t1, attributes);
301 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
302 return build_type_attribute_variant (t2, attributes);
304 /* Perform the integral promotions. */
305 if (code1 != REAL_TYPE)
307 t1 = type_promotes_to (t1);
308 t2 = type_promotes_to (t2);
311 /* Both real or both integers; use the one with greater precision. */
312 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
313 return build_type_attribute_variant (t1, attributes);
314 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
315 return build_type_attribute_variant (t2, attributes);
317 /* The types are the same; no need to do anything fancy. */
318 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
319 return build_type_attribute_variant (t1, attributes);
321 if (code1 != REAL_TYPE)
323 /* If one is a sizetype, use it so size_binop doesn't blow up. */
324 if (TYPE_IS_SIZETYPE (t1) > TYPE_IS_SIZETYPE (t2))
325 return build_type_attribute_variant (t1, attributes);
326 if (TYPE_IS_SIZETYPE (t2) > TYPE_IS_SIZETYPE (t1))
327 return build_type_attribute_variant (t2, attributes);
329 /* If one is unsigned long long, then convert the other to unsigned
331 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
332 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
333 return build_type_attribute_variant (long_long_unsigned_type_node,
335 /* If one is a long long, and the other is an unsigned long, and
336 long long can represent all the values of an unsigned long, then
337 convert to a long long. Otherwise, convert to an unsigned long
338 long. Otherwise, if either operand is long long, convert the
341 Since we're here, we know the TYPE_PRECISION is the same;
342 therefore converting to long long cannot represent all the values
343 of an unsigned long, so we choose unsigned long long in that
345 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
346 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
348 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
349 ? long_long_unsigned_type_node
350 : long_long_integer_type_node);
351 return build_type_attribute_variant (t, attributes);
354 /* Go through the same procedure, but for longs. */
355 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
356 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
357 return build_type_attribute_variant (long_unsigned_type_node,
359 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
360 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
362 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
363 ? long_unsigned_type_node : long_integer_type_node);
364 return build_type_attribute_variant (t, attributes);
366 /* Otherwise prefer the unsigned one. */
367 if (TYPE_UNSIGNED (t1))
368 return build_type_attribute_variant (t1, attributes);
370 return build_type_attribute_variant (t2, attributes);
374 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
375 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
376 return build_type_attribute_variant (long_double_type_node,
378 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
379 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
380 return build_type_attribute_variant (double_type_node,
382 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
383 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
384 return build_type_attribute_variant (float_type_node,
387 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
388 the standard C++ floating-point types. Logic earlier in this
389 function has already eliminated the possibility that
390 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
391 compelling reason to choose one or the other. */
392 return build_type_attribute_variant (t1, attributes);
396 /* Subroutine of composite_pointer_type to implement the recursive
397 case. See that function for documentation fo the parameters. */
400 composite_pointer_type_r (tree t1, tree t2, const char* location)
407 /* Determine the types pointed to by T1 and T2. */
408 if (TREE_CODE (t1) == POINTER_TYPE)
410 pointee1 = TREE_TYPE (t1);
411 pointee2 = TREE_TYPE (t2);
415 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
416 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
421 Otherwise, the composite pointer type is a pointer type
422 similar (_conv.qual_) to the type of one of the operands,
423 with a cv-qualification signature (_conv.qual_) that is the
424 union of the cv-qualification signatures of the operand
426 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
427 result_type = pointee1;
428 else if ((TREE_CODE (pointee1) == POINTER_TYPE
429 && TREE_CODE (pointee2) == POINTER_TYPE)
430 || (TYPE_PTR_TO_MEMBER_P (pointee1)
431 && TYPE_PTR_TO_MEMBER_P (pointee2)))
432 result_type = composite_pointer_type_r (pointee1, pointee2, location);
435 pedwarn ("%s between distinct pointer types %qT and %qT "
438 result_type = void_type_node;
440 result_type = cp_build_qualified_type (result_type,
441 (cp_type_quals (pointee1)
442 | cp_type_quals (pointee2)));
443 /* If the original types were pointers to members, so is the
445 if (TYPE_PTR_TO_MEMBER_P (t1))
447 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
448 TYPE_PTRMEM_CLASS_TYPE (t2)))
449 pedwarn ("%s between distinct pointer types %qT and %qT "
452 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
456 result_type = build_pointer_type (result_type);
458 /* Merge the attributes. */
459 attributes = (*targetm.merge_type_attributes) (t1, t2);
460 return build_type_attribute_variant (result_type, attributes);
463 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
464 ARG1 and ARG2 are the values with those types. The LOCATION is a
465 string describing the current location, in case an error occurs.
467 This routine also implements the computation of a common type for
468 pointers-to-members as per [expr.eq]. */
471 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
472 const char* location)
479 If one operand is a null pointer constant, the composite pointer
480 type is the type of the other operand. */
481 if (null_ptr_cst_p (arg1))
483 if (null_ptr_cst_p (arg2))
490 If one of the operands has type "pointer to cv1 void*", then
491 the other has type "pointer to cv2T", and the composite pointer
492 type is "pointer to cv12 void", where cv12 is the union of cv1
495 If either type is a pointer to void, make sure it is T1. */
496 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
504 /* Now, if T1 is a pointer to void, merge the qualifiers. */
505 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
510 if (pedantic && TYPE_PTRFN_P (t2))
511 pedwarn ("ISO C++ forbids %s between pointer of type %<void *%> "
512 "and pointer-to-function", location);
514 = cp_build_qualified_type (void_type_node,
515 (cp_type_quals (TREE_TYPE (t1))
516 | cp_type_quals (TREE_TYPE (t2))));
517 result_type = build_pointer_type (result_type);
518 /* Merge the attributes. */
519 attributes = (*targetm.merge_type_attributes) (t1, t2);
520 return build_type_attribute_variant (result_type, attributes);
523 if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE
524 && TREE_CODE (t2) == POINTER_TYPE)
526 if (objc_compare_types (t1, t2, -3, NULL_TREE))
530 /* [expr.eq] permits the application of a pointer conversion to
531 bring the pointers to a common type. */
532 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
533 && CLASS_TYPE_P (TREE_TYPE (t1))
534 && CLASS_TYPE_P (TREE_TYPE (t2))
535 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
538 class1 = TREE_TYPE (t1);
539 class2 = TREE_TYPE (t2);
541 if (DERIVED_FROM_P (class1, class2))
542 t2 = (build_pointer_type
543 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
544 else if (DERIVED_FROM_P (class2, class1))
545 t1 = (build_pointer_type
546 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
549 error ("%s between distinct pointer types %qT and %qT "
550 "lacks a cast", location, t1, t2);
551 return error_mark_node;
554 /* [expr.eq] permits the application of a pointer-to-member
555 conversion to change the class type of one of the types. */
556 else if (TYPE_PTR_TO_MEMBER_P (t1)
557 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
558 TYPE_PTRMEM_CLASS_TYPE (t2)))
560 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
561 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
563 if (DERIVED_FROM_P (class1, class2))
564 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
565 else if (DERIVED_FROM_P (class2, class1))
566 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
569 error ("%s between distinct pointer-to-member types %qT and %qT "
570 "lacks a cast", location, t1, t2);
571 return error_mark_node;
575 return composite_pointer_type_r (t1, t2, location);
578 /* Return the merged type of two types.
579 We assume that comptypes has already been done and returned 1;
580 if that isn't so, this may crash.
582 This just combines attributes and default arguments; any other
583 differences would cause the two types to compare unalike. */
586 merge_types (tree t1, tree t2)
588 enum tree_code code1;
589 enum tree_code code2;
592 /* Save time if the two types are the same. */
595 if (original_type (t1) == original_type (t2))
598 /* If one type is nonsense, use the other. */
599 if (t1 == error_mark_node)
601 if (t2 == error_mark_node)
604 /* Merge the attributes. */
605 attributes = (*targetm.merge_type_attributes) (t1, t2);
607 if (TYPE_PTRMEMFUNC_P (t1))
608 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
609 if (TYPE_PTRMEMFUNC_P (t2))
610 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
612 code1 = TREE_CODE (t1);
613 code2 = TREE_CODE (t2);
619 /* For two pointers, do this recursively on the target type. */
621 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
622 int quals = cp_type_quals (t1);
624 if (code1 == POINTER_TYPE)
625 t1 = build_pointer_type (target);
627 t1 = build_reference_type (target);
628 t1 = build_type_attribute_variant (t1, attributes);
629 t1 = cp_build_qualified_type (t1, quals);
631 if (TREE_CODE (target) == METHOD_TYPE)
632 t1 = build_ptrmemfunc_type (t1);
641 quals = cp_type_quals (t1);
642 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
643 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
644 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
646 t1 = cp_build_qualified_type (t1, quals);
652 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
653 /* Save space: see if the result is identical to one of the args. */
654 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
655 return build_type_attribute_variant (t1, attributes);
656 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
657 return build_type_attribute_variant (t2, attributes);
658 /* Merge the element types, and have a size if either arg has one. */
659 t1 = build_cplus_array_type
660 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
665 /* Function types: prefer the one that specified arg types.
666 If both do, merge the arg types. Also merge the return types. */
668 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
669 tree p1 = TYPE_ARG_TYPES (t1);
670 tree p2 = TYPE_ARG_TYPES (t2);
673 /* Save space: see if the result is identical to one of the args. */
674 if (valtype == TREE_TYPE (t1) && ! p2)
675 return cp_build_type_attribute_variant (t1, attributes);
676 if (valtype == TREE_TYPE (t2) && ! p1)
677 return cp_build_type_attribute_variant (t2, attributes);
679 /* Simple way if one arg fails to specify argument types. */
680 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
682 rval = build_function_type (valtype, p2);
683 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
684 rval = build_exception_variant (rval, raises);
685 return cp_build_type_attribute_variant (rval, attributes);
687 raises = TYPE_RAISES_EXCEPTIONS (t1);
688 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
690 rval = build_function_type (valtype, p1);
692 rval = build_exception_variant (rval, raises);
693 return cp_build_type_attribute_variant (rval, attributes);
696 rval = build_function_type (valtype, commonparms (p1, p2));
697 t1 = build_exception_variant (rval, raises);
703 /* Get this value the long way, since TYPE_METHOD_BASETYPE
704 is just the main variant of this. */
705 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
706 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
709 /* If this was a member function type, get back to the
710 original type of type member function (i.e., without
711 the class instance variable up front. */
712 t1 = build_function_type (TREE_TYPE (t1),
713 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
714 t2 = build_function_type (TREE_TYPE (t2),
715 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
716 t3 = merge_types (t1, t2);
717 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
718 TYPE_ARG_TYPES (t3));
719 t1 = build_exception_variant (t3, raises);
724 /* There is no need to merge attributes into a TYPENAME_TYPE.
725 When the type is instantiated it will have whatever
726 attributes result from the instantiation. */
731 return cp_build_type_attribute_variant (t1, attributes);
734 /* Return the common type of two types.
735 We assume that comptypes has already been done and returned 1;
736 if that isn't so, this may crash.
738 This is the type for the result of most arithmetic operations
739 if the operands have the given two types. */
742 common_type (tree t1, tree t2)
744 enum tree_code code1;
745 enum tree_code code2;
747 /* If one type is nonsense, bail. */
748 if (t1 == error_mark_node || t2 == error_mark_node)
749 return error_mark_node;
751 code1 = TREE_CODE (t1);
752 code2 = TREE_CODE (t2);
754 if ((ARITHMETIC_TYPE_P (t1) || code1 == ENUMERAL_TYPE
755 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
756 && (ARITHMETIC_TYPE_P (t2) || code2 == ENUMERAL_TYPE
757 || code2 == COMPLEX_TYPE || code2 == VECTOR_TYPE))
758 return type_after_usual_arithmetic_conversions (t1, t2);
760 else if ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
761 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
762 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)))
763 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
769 /* Compare two exception specifier types for exactness or subsetness, if
770 allowed. Returns false for mismatch, true for match (same, or
773 [except.spec] "If a class X ... objects of class X or any class publicly
774 and unambiguously derived from X. Similarly, if a pointer type Y * ...
775 exceptions of type Y * or that are pointers to any type publicly and
776 unambiguously derived from Y. Otherwise a function only allows exceptions
777 that have the same type ..."
778 This does not mention cv qualifiers and is different to what throw
779 [except.throw] and catch [except.catch] will do. They will ignore the
780 top level cv qualifiers, and allow qualifiers in the pointer to class
783 We implement the letter of the standard. */
786 comp_except_types (tree a, tree b, bool exact)
788 if (same_type_p (a, b))
792 if (cp_type_quals (a) || cp_type_quals (b))
795 if (TREE_CODE (a) == POINTER_TYPE
796 && TREE_CODE (b) == POINTER_TYPE)
800 if (cp_type_quals (a) || cp_type_quals (b))
804 if (TREE_CODE (a) != RECORD_TYPE
805 || TREE_CODE (b) != RECORD_TYPE)
808 if (PUBLICLY_UNIQUELY_DERIVED_P (a, b))
814 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
815 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
816 otherwise it must be exact. Exception lists are unordered, but
817 we've already filtered out duplicates. Most lists will be in order,
818 we should try to make use of that. */
821 comp_except_specs (tree t1, tree t2, bool exact)
830 if (t1 == NULL_TREE) /* T1 is ... */
831 return t2 == NULL_TREE || !exact;
832 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
833 return t2 != NULL_TREE && !TREE_VALUE (t2);
834 if (t2 == NULL_TREE) /* T2 is ... */
836 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
839 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
840 Count how many we find, to determine exactness. For exact matching and
841 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
843 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
845 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
847 tree a = TREE_VALUE (probe);
848 tree b = TREE_VALUE (t2);
850 if (comp_except_types (a, b, exact))
852 if (probe == base && exact)
853 base = TREE_CHAIN (probe);
858 if (probe == NULL_TREE)
861 return !exact || base == NULL_TREE || length == list_length (t1);
864 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
865 [] can match [size]. */
868 comp_array_types (tree t1, tree t2, bool allow_redeclaration)
877 /* The type of the array elements must be the same. */
878 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
881 d1 = TYPE_DOMAIN (t1);
882 d2 = TYPE_DOMAIN (t2);
887 /* If one of the arrays is dimensionless, and the other has a
888 dimension, they are of different types. However, it is valid to
896 declarations for an array object can specify
897 array types that differ by the presence or absence of a major
898 array bound (_dcl.array_). */
900 return allow_redeclaration;
902 /* Check that the dimensions are the same. */
904 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
906 max1 = TYPE_MAX_VALUE (d1);
907 max2 = TYPE_MAX_VALUE (d2);
908 if (processing_template_decl && !abi_version_at_least (2)
909 && !value_dependent_expression_p (max1)
910 && !value_dependent_expression_p (max2))
912 /* With abi-1 we do not fold non-dependent array bounds, (and
913 consequently mangle them incorrectly). We must therefore
914 fold them here, to verify the domains have the same
920 if (!cp_tree_equal (max1, max2))
926 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
927 is a bitwise-or of the COMPARE_* flags. */
930 comptypes (tree t1, tree t2, int strict)
935 /* Suppress errors caused by previously reported errors. */
936 if (t1 == error_mark_node || t2 == error_mark_node)
939 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
941 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
942 current instantiation. */
943 if (TREE_CODE (t1) == TYPENAME_TYPE)
945 tree resolved = resolve_typename_type (t1, /*only_current_p=*/true);
947 if (resolved != error_mark_node)
951 if (TREE_CODE (t2) == TYPENAME_TYPE)
953 tree resolved = resolve_typename_type (t2, /*only_current_p=*/true);
955 if (resolved != error_mark_node)
959 /* If either type is the internal version of sizetype, use the
961 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
962 && TYPE_ORIG_SIZE_TYPE (t1))
963 t1 = TYPE_ORIG_SIZE_TYPE (t1);
965 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
966 && TYPE_ORIG_SIZE_TYPE (t2))
967 t2 = TYPE_ORIG_SIZE_TYPE (t2);
969 if (TYPE_PTRMEMFUNC_P (t1))
970 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
971 if (TYPE_PTRMEMFUNC_P (t2))
972 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
974 /* Different classes of types can't be compatible. */
975 if (TREE_CODE (t1) != TREE_CODE (t2))
978 /* Qualifiers must match. For array types, we will check when we
979 recur on the array element types. */
980 if (TREE_CODE (t1) != ARRAY_TYPE
981 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
983 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
986 /* Allow for two different type nodes which have essentially the same
987 definition. Note that we already checked for equality of the type
988 qualifiers (just above). */
990 if (TREE_CODE (t1) != ARRAY_TYPE
991 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
994 /* Compare the types. Break out if they could be the same. */
995 switch (TREE_CODE (t1))
997 case TEMPLATE_TEMPLATE_PARM:
998 case BOUND_TEMPLATE_TEMPLATE_PARM:
999 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1000 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
1002 if (!comp_template_parms
1003 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1004 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1006 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1008 /* Don't check inheritance. */
1009 strict = COMPARE_STRICT;
1014 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1015 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1016 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1017 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1020 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1022 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1028 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1029 strict & ~COMPARE_REDECLARATION))
1031 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1036 case REFERENCE_TYPE:
1037 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1038 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)
1039 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1045 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1047 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1052 /* Target types must match incl. qualifiers. */
1053 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1057 case TEMPLATE_TYPE_PARM:
1058 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1059 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
1064 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1065 TYPENAME_TYPE_FULLNAME (t2)))
1067 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1071 case UNBOUND_CLASS_TEMPLATE:
1072 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1074 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1079 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1084 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1085 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1093 /* If we get here, we know that from a target independent POV the
1094 types are the same. Make sure the target attributes are also
1096 return targetm.comp_type_attributes (t1, t2);
1099 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1102 at_least_as_qualified_p (tree type1, tree type2)
1104 int q1 = cp_type_quals (type1);
1105 int q2 = cp_type_quals (type2);
1107 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1108 return (q1 & q2) == q2;
1111 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1112 more cv-qualified that TYPE1, and 0 otherwise. */
1115 comp_cv_qualification (tree type1, tree type2)
1117 int q1 = cp_type_quals (type1);
1118 int q2 = cp_type_quals (type2);
1123 if ((q1 & q2) == q2)
1125 else if ((q1 & q2) == q1)
1131 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1132 subset of the cv-qualification signature of TYPE2, and the types
1133 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1136 comp_cv_qual_signature (tree type1, tree type2)
1138 if (comp_ptr_ttypes_real (type2, type1, -1))
1140 else if (comp_ptr_ttypes_real (type1, type2, -1))
1146 /* If two types share a common base type, return that basetype.
1147 If there is not a unique most-derived base type, this function
1148 returns ERROR_MARK_NODE. */
1151 common_base_type (tree tt1, tree tt2)
1153 tree best = NULL_TREE;
1156 /* If one is a baseclass of another, that's good enough. */
1157 if (UNIQUELY_DERIVED_FROM_P (tt1, tt2))
1159 if (UNIQUELY_DERIVED_FROM_P (tt2, tt1))
1162 /* Otherwise, try to find a unique baseclass of TT1
1163 that is shared by TT2, and follow that down. */
1164 for (i = BINFO_N_BASE_BINFOS (TYPE_BINFO (tt1))-1; i >= 0; i--)
1166 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (tt1), i));
1167 tree trial = common_base_type (basetype, tt2);
1171 if (trial == error_mark_node)
1173 if (best == NULL_TREE)
1175 else if (best != trial)
1176 return error_mark_node;
1181 for (i = BINFO_N_BASE_BINFOS (TYPE_BINFO (tt2))-1; i >= 0; i--)
1183 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (tt2), i));
1184 tree trial = common_base_type (tt1, basetype);
1188 if (trial == error_mark_node)
1190 if (best == NULL_TREE)
1192 else if (best != trial)
1193 return error_mark_node;
1199 /* Subroutines of `comptypes'. */
1201 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1202 equivalent in the sense that functions with those parameter types
1203 can have equivalent types. The two lists must be equivalent,
1204 element by element. */
1207 compparms (tree parms1, tree parms2)
1211 /* An unspecified parmlist matches any specified parmlist
1212 whose argument types don't need default promotions. */
1214 for (t1 = parms1, t2 = parms2;
1216 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1218 /* If one parmlist is shorter than the other,
1219 they fail to match. */
1222 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1229 /* Process a sizeof or alignof expression where the operand is a
1233 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1235 enum tree_code type_code;
1237 const char *op_name;
1239 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1240 if (type == error_mark_node)
1241 return error_mark_node;
1243 if (dependent_type_p (type))
1245 value = build_min (op, size_type_node, type);
1246 TREE_READONLY (value) = 1;
1250 op_name = operator_name_info[(int) op].name;
1252 type = non_reference (type);
1253 type_code = TREE_CODE (type);
1255 if (type_code == METHOD_TYPE)
1257 if (complain && (pedantic || warn_pointer_arith))
1258 pedwarn ("invalid application of %qs to a member function", op_name);
1259 value = size_one_node;
1262 value = c_sizeof_or_alignof_type (complete_type (type),
1269 /* Process a sizeof or alignof expression where the operand is an
1273 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op)
1275 const char *op_name = operator_name_info[(int) op].name;
1277 if (e == error_mark_node)
1278 return error_mark_node;
1280 if (processing_template_decl)
1282 e = build_min (op, size_type_node, e);
1283 TREE_SIDE_EFFECTS (e) = 0;
1284 TREE_READONLY (e) = 1;
1289 if (TREE_CODE (e) == COMPONENT_REF
1290 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1291 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1293 error ("invalid application of %qs to a bit-field", op_name);
1296 else if (is_overloaded_fn (e))
1298 pedwarn ("ISO C++ forbids applying %qs to an expression of "
1299 "function type", op_name);
1302 else if (type_unknown_p (e))
1304 cxx_incomplete_type_error (e, TREE_TYPE (e));
1310 return cxx_sizeof_or_alignof_type (e, op, true);
1314 /* EXPR is being used in a context that is not a function call.
1319 The expression can be used only as the left-hand operand of a
1320 member function call.
1322 [expr.mptr.operator]
1324 If the result of .* or ->* is a function, then that result can be
1325 used only as the operand for the function call operator ().
1327 by issuing an error message if appropriate. Returns true iff EXPR
1328 violates these rules. */
1331 invalid_nonstatic_memfn_p (tree expr)
1333 if (TREE_CODE (TREE_TYPE (expr)) == METHOD_TYPE)
1335 error ("invalid use of non-static member function");
1341 /* Perform the conversions in [expr] that apply when an lvalue appears
1342 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1343 function-to-pointer conversions.
1345 In addition manifest constants are replaced by their values. */
1348 decay_conversion (tree exp)
1351 enum tree_code code;
1353 type = TREE_TYPE (exp);
1354 code = TREE_CODE (type);
1356 if (type == error_mark_node)
1357 return error_mark_node;
1359 if (type_unknown_p (exp))
1361 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1362 return error_mark_node;
1365 exp = decl_constant_value (exp);
1367 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1368 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1370 if (code == VOID_TYPE)
1372 error ("void value not ignored as it ought to be");
1373 return error_mark_node;
1375 if (invalid_nonstatic_memfn_p (exp))
1376 return error_mark_node;
1377 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1378 return build_unary_op (ADDR_EXPR, exp, 0);
1379 if (code == ARRAY_TYPE)
1384 if (TREE_CODE (exp) == INDIRECT_REF)
1385 return build_nop (build_pointer_type (TREE_TYPE (type)),
1386 TREE_OPERAND (exp, 0));
1388 if (TREE_CODE (exp) == COMPOUND_EXPR)
1390 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1391 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1392 TREE_OPERAND (exp, 0), op1);
1396 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1398 error ("invalid use of non-lvalue array");
1399 return error_mark_node;
1402 ptrtype = build_pointer_type (TREE_TYPE (type));
1404 if (TREE_CODE (exp) == VAR_DECL)
1406 if (!cxx_mark_addressable (exp))
1407 return error_mark_node;
1408 adr = build_nop (ptrtype, build_address (exp));
1411 /* This way is better for a COMPONENT_REF since it can
1412 simplify the offset for a component. */
1413 adr = build_unary_op (ADDR_EXPR, exp, 1);
1414 return cp_convert (ptrtype, adr);
1417 /* [basic.lval]: Class rvalues can have cv-qualified types; non-class
1418 rvalues always have cv-unqualified types. */
1419 if (! CLASS_TYPE_P (type))
1420 exp = cp_convert (TYPE_MAIN_VARIANT (type), exp);
1426 default_conversion (tree exp)
1428 exp = decay_conversion (exp);
1430 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1431 exp = perform_integral_promotions (exp);
1436 /* EXPR is an expression with an integral or enumeration type.
1437 Perform the integral promotions in [conv.prom], and return the
1441 perform_integral_promotions (tree expr)
1446 type = TREE_TYPE (expr);
1447 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1448 promoted_type = type_promotes_to (type);
1449 if (type != promoted_type)
1450 expr = cp_convert (promoted_type, expr);
1454 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1458 inline_conversion (tree exp)
1460 if (TREE_CODE (exp) == FUNCTION_DECL)
1461 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1466 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1467 decay_conversion to one. */
1470 string_conv_p (tree totype, tree exp, int warn)
1474 if (! flag_const_strings || TREE_CODE (totype) != POINTER_TYPE)
1477 t = TREE_TYPE (totype);
1478 if (!same_type_p (t, char_type_node)
1479 && !same_type_p (t, wchar_type_node))
1482 if (TREE_CODE (exp) == STRING_CST)
1484 /* Make sure that we don't try to convert between char and wchar_t. */
1485 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1490 /* Is this a string constant which has decayed to 'const char *'? */
1491 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1492 if (!same_type_p (TREE_TYPE (exp), t))
1495 if (TREE_CODE (exp) != ADDR_EXPR
1496 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1500 /* This warning is not very useful, as it complains about printf. */
1501 if (warn && warn_write_strings)
1502 warning (0, "deprecated conversion from string constant to %qT'", totype);
1507 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1508 can, for example, use as an lvalue. This code used to be in
1509 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1510 expressions, where we're dealing with aggregates. But now it's again only
1511 called from unary_complex_lvalue. The case (in particular) that led to
1512 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1516 rationalize_conditional_expr (enum tree_code code, tree t)
1518 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1519 the first operand is always the one to be used if both operands
1520 are equal, so we know what conditional expression this used to be. */
1521 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1523 /* The following code is incorrect if either operand side-effects. */
1524 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0))
1525 && !TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)));
1527 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1528 ? LE_EXPR : GE_EXPR),
1529 TREE_OPERAND (t, 0),
1530 TREE_OPERAND (t, 1),
1531 /*overloaded_p=*/NULL),
1532 build_unary_op (code, TREE_OPERAND (t, 0), 0),
1533 build_unary_op (code, TREE_OPERAND (t, 1), 0));
1537 build_conditional_expr (TREE_OPERAND (t, 0),
1538 build_unary_op (code, TREE_OPERAND (t, 1), 0),
1539 build_unary_op (code, TREE_OPERAND (t, 2), 0));
1542 /* Given the TYPE of an anonymous union field inside T, return the
1543 FIELD_DECL for the field. If not found return NULL_TREE. Because
1544 anonymous unions can nest, we must also search all anonymous unions
1545 that are directly reachable. */
1548 lookup_anon_field (tree t, tree type)
1552 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1554 if (TREE_STATIC (field))
1556 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1559 /* If we find it directly, return the field. */
1560 if (DECL_NAME (field) == NULL_TREE
1561 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1566 /* Otherwise, it could be nested, search harder. */
1567 if (DECL_NAME (field) == NULL_TREE
1568 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1570 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1578 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1579 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1580 non-NULL, it indicates the path to the base used to name MEMBER.
1581 If PRESERVE_REFERENCE is true, the expression returned will have
1582 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1583 returned will have the type referred to by the reference.
1585 This function does not perform access control; that is either done
1586 earlier by the parser when the name of MEMBER is resolved to MEMBER
1587 itself, or later when overload resolution selects one of the
1588 functions indicated by MEMBER. */
1591 build_class_member_access_expr (tree object, tree member,
1592 tree access_path, bool preserve_reference)
1596 tree result = NULL_TREE;
1598 if (object == error_mark_node || member == error_mark_node)
1599 return error_mark_node;
1601 gcc_assert (DECL_P (member) || BASELINK_P (member));
1605 The type of the first expression shall be "class object" (of a
1607 object_type = TREE_TYPE (object);
1608 if (!currently_open_class (object_type)
1609 && !complete_type_or_else (object_type, object))
1610 return error_mark_node;
1611 if (!CLASS_TYPE_P (object_type))
1613 error ("request for member %qD in %qE, which is of non-class type %qT",
1614 member, object, object_type);
1615 return error_mark_node;
1618 /* The standard does not seem to actually say that MEMBER must be a
1619 member of OBJECT_TYPE. However, that is clearly what is
1621 if (DECL_P (member))
1623 member_scope = DECL_CLASS_CONTEXT (member);
1625 if (TREE_DEPRECATED (member))
1626 warn_deprecated_use (member);
1629 member_scope = BINFO_TYPE (BASELINK_BINFO (member));
1630 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1631 presently be the anonymous union. Go outwards until we find a
1632 type related to OBJECT_TYPE. */
1633 while (ANON_AGGR_TYPE_P (member_scope)
1634 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1636 member_scope = TYPE_CONTEXT (member_scope);
1637 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1639 if (TREE_CODE (member) == FIELD_DECL)
1640 error ("invalid use of nonstatic data member %qE", member);
1642 error ("%qD is not a member of %qT", member, object_type);
1643 return error_mark_node;
1646 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1647 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1648 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1650 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1652 object = build_indirect_ref (temp, NULL);
1655 /* In [expr.ref], there is an explicit list of the valid choices for
1656 MEMBER. We check for each of those cases here. */
1657 if (TREE_CODE (member) == VAR_DECL)
1659 /* A static data member. */
1661 /* If OBJECT has side-effects, they are supposed to occur. */
1662 if (TREE_SIDE_EFFECTS (object))
1663 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1665 else if (TREE_CODE (member) == FIELD_DECL)
1667 /* A non-static data member. */
1672 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1673 && integer_zerop (TREE_OPERAND (object, 0)));
1675 /* Convert OBJECT to the type of MEMBER. */
1676 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1677 TYPE_MAIN_VARIANT (member_scope)))
1682 binfo = lookup_base (access_path ? access_path : object_type,
1683 member_scope, ba_unique, &kind);
1684 if (binfo == error_mark_node)
1685 return error_mark_node;
1687 /* It is invalid to try to get to a virtual base of a
1688 NULL object. The most common cause is invalid use of
1690 if (null_object_p && kind == bk_via_virtual)
1692 error ("invalid access to non-static data member %qD of "
1695 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
1696 return error_mark_node;
1699 /* Convert to the base. */
1700 object = build_base_path (PLUS_EXPR, object, binfo,
1702 /* If we found the base successfully then we should be able
1703 to convert to it successfully. */
1704 gcc_assert (object != error_mark_node);
1707 /* Complain about other invalid uses of offsetof, even though they will
1708 give the right answer. Note that we complain whether or not they
1709 actually used the offsetof macro, since there's no way to know at this
1710 point. So we just give a warning, instead of a pedwarn. */
1711 /* Do not produce this warning for base class field references, because
1712 we know for a fact that didn't come from offsetof. This does occur
1713 in various testsuite cases where a null object is passed where a
1714 vtable access is required. */
1715 if (null_object_p && warn_invalid_offsetof
1716 && CLASSTYPE_NON_POD_P (object_type)
1717 && !DECL_FIELD_IS_BASE (member)
1718 && !skip_evaluation)
1720 warning (0, "invalid access to non-static data member %qD of NULL object",
1722 warning (0, "(perhaps the %<offsetof%> macro was used incorrectly)");
1725 /* If MEMBER is from an anonymous aggregate, we have converted
1726 OBJECT so that it refers to the class containing the
1727 anonymous union. Generate a reference to the anonymous union
1728 itself, and recur to find MEMBER. */
1729 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
1730 /* When this code is called from build_field_call, the
1731 object already has the type of the anonymous union.
1732 That is because the COMPONENT_REF was already
1733 constructed, and was then disassembled before calling
1734 build_field_call. After the function-call code is
1735 cleaned up, this waste can be eliminated. */
1736 && (!same_type_ignoring_top_level_qualifiers_p
1737 (TREE_TYPE (object), DECL_CONTEXT (member))))
1739 tree anonymous_union;
1741 anonymous_union = lookup_anon_field (TREE_TYPE (object),
1742 DECL_CONTEXT (member));
1743 object = build_class_member_access_expr (object,
1745 /*access_path=*/NULL_TREE,
1746 preserve_reference);
1749 /* Compute the type of the field, as described in [expr.ref]. */
1750 type_quals = TYPE_UNQUALIFIED;
1751 member_type = TREE_TYPE (member);
1752 if (TREE_CODE (member_type) != REFERENCE_TYPE)
1754 type_quals = (cp_type_quals (member_type)
1755 | cp_type_quals (object_type));
1757 /* A field is const (volatile) if the enclosing object, or the
1758 field itself, is const (volatile). But, a mutable field is
1759 not const, even within a const object. */
1760 if (DECL_MUTABLE_P (member))
1761 type_quals &= ~TYPE_QUAL_CONST;
1762 member_type = cp_build_qualified_type (member_type, type_quals);
1765 result = build3 (COMPONENT_REF, member_type, object, member,
1767 result = fold_if_not_in_template (result);
1769 /* Mark the expression const or volatile, as appropriate. Even
1770 though we've dealt with the type above, we still have to mark the
1771 expression itself. */
1772 if (type_quals & TYPE_QUAL_CONST)
1773 TREE_READONLY (result) = 1;
1774 if (type_quals & TYPE_QUAL_VOLATILE)
1775 TREE_THIS_VOLATILE (result) = 1;
1777 else if (BASELINK_P (member))
1779 /* The member is a (possibly overloaded) member function. */
1783 /* If the MEMBER is exactly one static member function, then we
1784 know the type of the expression. Otherwise, we must wait
1785 until overload resolution has been performed. */
1786 functions = BASELINK_FUNCTIONS (member);
1787 if (TREE_CODE (functions) == FUNCTION_DECL
1788 && DECL_STATIC_FUNCTION_P (functions))
1789 type = TREE_TYPE (functions);
1791 type = unknown_type_node;
1792 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1793 base. That will happen when the function is called. */
1794 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
1796 else if (TREE_CODE (member) == CONST_DECL)
1798 /* The member is an enumerator. */
1800 /* If OBJECT has side-effects, they are supposed to occur. */
1801 if (TREE_SIDE_EFFECTS (object))
1802 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
1807 error ("invalid use of %qD", member);
1808 return error_mark_node;
1811 if (!preserve_reference)
1814 If E2 is declared to have type "reference to T", then ... the
1815 type of E1.E2 is T. */
1816 result = convert_from_reference (result);
1821 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1822 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1825 lookup_destructor (tree object, tree scope, tree dtor_name)
1827 tree object_type = TREE_TYPE (object);
1828 tree dtor_type = TREE_OPERAND (dtor_name, 0);
1831 if (scope && !check_dtor_name (scope, dtor_name))
1833 error ("qualified type %qT does not match destructor name ~%qT",
1835 return error_mark_node;
1837 if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
1839 error ("the type being destroyed is %qT, but the destructor refers to %qT",
1840 TYPE_MAIN_VARIANT (object_type), dtor_type);
1841 return error_mark_node;
1843 expr = lookup_member (dtor_type, complete_dtor_identifier,
1844 /*protect=*/1, /*want_type=*/false);
1845 expr = (adjust_result_of_qualified_name_lookup
1846 (expr, dtor_type, object_type));
1850 /* An expression of the form "A::template B" has been resolved to
1851 DECL. Issue a diagnostic if B is not a template or template
1855 check_template_keyword (tree decl)
1857 /* The standard says:
1861 If a name prefixed by the keyword template is not a member
1862 template, the program is ill-formed.
1864 DR 228 removed the restriction that the template be a member
1867 DR 96, if accepted would add the further restriction that explicit
1868 template arguments must be provided if the template keyword is
1869 used, but, as of 2005-10-16, that DR is still in "drafting". If
1870 this DR is accepted, then the semantic checks here can be
1871 simplified, as the entity named must in fact be a template
1872 specialization, rather than, as at present, a set of overloaded
1873 functions containing at least one template function. */
1874 if (TREE_CODE (decl) != TEMPLATE_DECL
1875 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
1877 if (!is_overloaded_fn (decl))
1878 pedwarn ("%qD is not a template", decl);
1883 if (BASELINK_P (fns))
1884 fns = BASELINK_FUNCTIONS (fns);
1887 tree fn = OVL_CURRENT (fns);
1888 if (TREE_CODE (fn) == TEMPLATE_DECL
1889 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
1891 if (TREE_CODE (fn) == FUNCTION_DECL
1892 && DECL_USE_TEMPLATE (fn)
1893 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
1895 fns = OVL_NEXT (fns);
1898 pedwarn ("%qD is not a template", decl);
1903 /* This function is called by the parser to process a class member
1904 access expression of the form OBJECT.NAME. NAME is a node used by
1905 the parser to represent a name; it is not yet a DECL. It may,
1906 however, be a BASELINK where the BASELINK_FUNCTIONS is a
1907 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
1908 there is no reason to do the lookup twice, so the parser keeps the
1909 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
1910 be a template via the use of the "A::template B" syntax. */
1913 finish_class_member_access_expr (tree object, tree name, bool template_p)
1918 tree access_path = NULL_TREE;
1919 tree orig_object = object;
1920 tree orig_name = name;
1922 if (object == error_mark_node || name == error_mark_node)
1923 return error_mark_node;
1925 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
1926 if (!objc_is_public (object, name))
1927 return error_mark_node;
1929 object_type = TREE_TYPE (object);
1931 if (processing_template_decl)
1933 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
1934 dependent_type_p (object_type)
1935 /* If NAME is just an IDENTIFIER_NODE, then the expression
1937 || TREE_CODE (object) == IDENTIFIER_NODE
1938 /* If NAME is "f<args>", where either 'f' or 'args' is
1939 dependent, then the expression is dependent. */
1940 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
1941 && dependent_template_id_p (TREE_OPERAND (name, 0),
1942 TREE_OPERAND (name, 1)))
1943 /* If NAME is "T::X" where "T" is dependent, then the
1944 expression is dependent. */
1945 || (TREE_CODE (name) == SCOPE_REF
1946 && TYPE_P (TREE_OPERAND (name, 0))
1947 && dependent_type_p (TREE_OPERAND (name, 0))))
1948 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
1949 object = build_non_dependent_expr (object);
1954 The type of the first expression shall be "class object" (of a
1956 if (!currently_open_class (object_type)
1957 && !complete_type_or_else (object_type, object))
1958 return error_mark_node;
1959 if (!CLASS_TYPE_P (object_type))
1961 error ("request for member %qD in %qE, which is of non-class type %qT",
1962 name, object, object_type);
1963 return error_mark_node;
1966 if (BASELINK_P (name))
1967 /* A member function that has already been looked up. */
1971 bool is_template_id = false;
1972 tree template_args = NULL_TREE;
1975 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
1977 is_template_id = true;
1978 template_args = TREE_OPERAND (name, 1);
1979 name = TREE_OPERAND (name, 0);
1981 if (TREE_CODE (name) == OVERLOAD)
1982 name = DECL_NAME (get_first_fn (name));
1983 else if (DECL_P (name))
1984 name = DECL_NAME (name);
1987 if (TREE_CODE (name) == SCOPE_REF)
1989 /* A qualified name. The qualifying class or namespace `S' has
1990 already been looked up; it is either a TYPE or a
1991 NAMESPACE_DECL. The member name is either an IDENTIFIER_NODE
1992 or a BIT_NOT_EXPR. */
1993 scope = TREE_OPERAND (name, 0);
1994 name = TREE_OPERAND (name, 1);
1995 gcc_assert (CLASS_TYPE_P (scope)
1996 || TREE_CODE (scope) == NAMESPACE_DECL);
1997 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
1998 || TREE_CODE (name) == BIT_NOT_EXPR);
2000 /* If SCOPE is a namespace, then the qualified name does not
2001 name a member of OBJECT_TYPE. */
2002 if (TREE_CODE (scope) == NAMESPACE_DECL)
2004 error ("%<%D::%D%> is not a member of %qT",
2005 scope, name, object_type);
2006 return error_mark_node;
2009 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2010 access_path = lookup_base (object_type, scope, ba_check, NULL);
2011 if (access_path == error_mark_node)
2012 return error_mark_node;
2015 error ("%qT is not a base of %qT", scope, object_type);
2016 return error_mark_node;
2022 access_path = object_type;
2025 if (TREE_CODE (name) == BIT_NOT_EXPR)
2026 member = lookup_destructor (object, scope, name);
2029 /* Look up the member. */
2030 member = lookup_member (access_path, name, /*protect=*/1,
2031 /*want_type=*/false);
2032 if (member == NULL_TREE)
2034 error ("%qD has no member named %qE", object_type, name);
2035 return error_mark_node;
2037 if (member == error_mark_node)
2038 return error_mark_node;
2043 tree template = member;
2045 if (BASELINK_P (template))
2046 template = lookup_template_function (template, template_args);
2049 error ("%qD is not a member template function", name);
2050 return error_mark_node;
2055 if (TREE_DEPRECATED (member))
2056 warn_deprecated_use (member);
2059 check_template_keyword (member);
2061 expr = build_class_member_access_expr (object, member, access_path,
2062 /*preserve_reference=*/false);
2063 if (processing_template_decl && expr != error_mark_node)
2065 if (BASELINK_P (member))
2067 if (TREE_CODE (orig_name) == SCOPE_REF)
2068 BASELINK_QUALIFIED_P (member) = 1;
2071 return build_min_non_dep (COMPONENT_REF, expr,
2072 orig_object, orig_name,
2079 /* Return an expression for the MEMBER_NAME field in the internal
2080 representation of PTRMEM, a pointer-to-member function. (Each
2081 pointer-to-member function type gets its own RECORD_TYPE so it is
2082 more convenient to access the fields by name than by FIELD_DECL.)
2083 This routine converts the NAME to a FIELD_DECL and then creates the
2084 node for the complete expression. */
2087 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2093 /* This code is a stripped down version of
2094 build_class_member_access_expr. It does not work to use that
2095 routine directly because it expects the object to be of class
2097 ptrmem_type = TREE_TYPE (ptrmem);
2098 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2099 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2100 /*want_type=*/false);
2101 member_type = cp_build_qualified_type (TREE_TYPE (member),
2102 cp_type_quals (ptrmem_type));
2103 return fold_build3 (COMPONENT_REF, member_type,
2104 ptrmem, member, NULL_TREE);
2107 /* Given an expression PTR for a pointer, return an expression
2108 for the value pointed to.
2109 ERRORSTRING is the name of the operator to appear in error messages.
2111 This function may need to overload OPERATOR_FNNAME.
2112 Must also handle REFERENCE_TYPEs for C++. */
2115 build_x_indirect_ref (tree expr, const char *errorstring)
2117 tree orig_expr = expr;
2120 if (processing_template_decl)
2122 if (type_dependent_expression_p (expr))
2123 return build_min_nt (INDIRECT_REF, expr);
2124 expr = build_non_dependent_expr (expr);
2127 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2128 NULL_TREE, /*overloaded_p=*/NULL);
2130 rval = build_indirect_ref (expr, errorstring);
2132 if (processing_template_decl && rval != error_mark_node)
2133 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2139 build_indirect_ref (tree ptr, const char *errorstring)
2143 if (ptr == error_mark_node)
2144 return error_mark_node;
2146 if (ptr == current_class_ptr)
2147 return current_class_ref;
2149 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2150 ? ptr : decay_conversion (ptr));
2151 type = TREE_TYPE (pointer);
2153 if (POINTER_TYPE_P (type))
2157 If the type of the expression is "pointer to T," the type
2158 of the result is "T."
2160 We must use the canonical variant because certain parts of
2161 the back end, like fold, do pointer comparisons between
2163 tree t = canonical_type_variant (TREE_TYPE (type));
2165 if (VOID_TYPE_P (t))
2167 /* A pointer to incomplete type (other than cv void) can be
2168 dereferenced [expr.unary.op]/1 */
2169 error ("%qT is not a pointer-to-object type", type);
2170 return error_mark_node;
2172 else if (TREE_CODE (pointer) == ADDR_EXPR
2173 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2174 /* The POINTER was something like `&x'. We simplify `*&x' to
2176 return TREE_OPERAND (pointer, 0);
2179 tree ref = build1 (INDIRECT_REF, t, pointer);
2181 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2182 so that we get the proper error message if the result is used
2183 to assign to. Also, &* is supposed to be a no-op. */
2184 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2185 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2186 TREE_SIDE_EFFECTS (ref)
2187 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2191 /* `pointer' won't be an error_mark_node if we were given a
2192 pointer to member, so it's cool to check for this here. */
2193 else if (TYPE_PTR_TO_MEMBER_P (type))
2194 error ("invalid use of %qs on pointer to member", errorstring);
2195 else if (pointer != error_mark_node)
2198 error ("invalid type argument of %qs", errorstring);
2200 error ("invalid type argument");
2202 return error_mark_node;
2205 /* This handles expressions of the form "a[i]", which denotes
2208 This is logically equivalent in C to *(a+i), but we may do it differently.
2209 If A is a variable or a member, we generate a primitive ARRAY_REF.
2210 This avoids forcing the array out of registers, and can work on
2211 arrays that are not lvalues (for example, members of structures returned
2214 If INDEX is of some user-defined type, it must be converted to
2215 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2216 will inherit the type of the array, which will be some pointer type. */
2219 build_array_ref (tree array, tree idx)
2223 error ("subscript missing in array reference");
2224 return error_mark_node;
2227 if (TREE_TYPE (array) == error_mark_node
2228 || TREE_TYPE (idx) == error_mark_node)
2229 return error_mark_node;
2231 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2233 switch (TREE_CODE (array))
2237 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2238 return build2 (COMPOUND_EXPR, TREE_TYPE (value),
2239 TREE_OPERAND (array, 0), value);
2243 return build_conditional_expr
2244 (TREE_OPERAND (array, 0),
2245 build_array_ref (TREE_OPERAND (array, 1), idx),
2246 build_array_ref (TREE_OPERAND (array, 2), idx));
2252 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2256 /* Subscripting with type char is likely to lose
2257 on a machine where chars are signed.
2258 So warn on any machine, but optionally.
2259 Don't warn for unsigned char since that type is safe.
2260 Don't warn for signed char because anyone who uses that
2261 must have done so deliberately. */
2262 if (warn_char_subscripts
2263 && TYPE_MAIN_VARIANT (TREE_TYPE (idx)) == char_type_node)
2264 warning (0, "array subscript has type %<char%>");
2266 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2268 error ("array subscript is not an integer");
2269 return error_mark_node;
2272 /* Apply integral promotions *after* noticing character types.
2273 (It is unclear why we do these promotions -- the standard
2274 does not say that we should. In fact, the natural thing would
2275 seem to be to convert IDX to ptrdiff_t; we're performing
2276 pointer arithmetic.) */
2277 idx = perform_integral_promotions (idx);
2279 /* An array that is indexed by a non-constant
2280 cannot be stored in a register; we must be able to do
2281 address arithmetic on its address.
2282 Likewise an array of elements of variable size. */
2283 if (TREE_CODE (idx) != INTEGER_CST
2284 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2285 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2288 if (!cxx_mark_addressable (array))
2289 return error_mark_node;
2292 /* An array that is indexed by a constant value which is not within
2293 the array bounds cannot be stored in a register either; because we
2294 would get a crash in store_bit_field/extract_bit_field when trying
2295 to access a non-existent part of the register. */
2296 if (TREE_CODE (idx) == INTEGER_CST
2297 && TYPE_DOMAIN (TREE_TYPE (array))
2298 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2300 if (!cxx_mark_addressable (array))
2301 return error_mark_node;
2304 if (pedantic && !lvalue_p (array))
2305 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2307 /* Note in C++ it is valid to subscript a `register' array, since
2308 it is valid to take the address of something with that
2309 storage specification. */
2313 while (TREE_CODE (foo) == COMPONENT_REF)
2314 foo = TREE_OPERAND (foo, 0);
2315 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2316 warning (0, "subscripting array declared %<register%>");
2319 type = TREE_TYPE (TREE_TYPE (array));
2320 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2321 /* Array ref is const/volatile if the array elements are
2322 or if the array is.. */
2323 TREE_READONLY (rval)
2324 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2325 TREE_SIDE_EFFECTS (rval)
2326 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2327 TREE_THIS_VOLATILE (rval)
2328 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2329 return require_complete_type (fold_if_not_in_template (rval));
2333 tree ar = default_conversion (array);
2334 tree ind = default_conversion (idx);
2336 /* Put the integer in IND to simplify error checking. */
2337 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2344 if (ar == error_mark_node)
2347 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2349 error ("subscripted value is neither array nor pointer");
2350 return error_mark_node;
2352 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2354 error ("array subscript is not an integer");
2355 return error_mark_node;
2358 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2363 /* Resolve a pointer to member function. INSTANCE is the object
2364 instance to use, if the member points to a virtual member.
2366 This used to avoid checking for virtual functions if basetype
2367 has no virtual functions, according to an earlier ANSI draft.
2368 With the final ISO C++ rules, such an optimization is
2369 incorrect: A pointer to a derived member can be static_cast
2370 to pointer-to-base-member, as long as the dynamic object
2371 later has the right member. */
2374 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2376 if (TREE_CODE (function) == OFFSET_REF)
2377 function = TREE_OPERAND (function, 1);
2379 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2381 tree idx, delta, e1, e2, e3, vtbl, basetype;
2382 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2384 tree instance_ptr = *instance_ptrptr;
2385 tree instance_save_expr = 0;
2386 if (instance_ptr == error_mark_node)
2388 if (TREE_CODE (function) == PTRMEM_CST)
2390 /* Extracting the function address from a pmf is only
2391 allowed with -Wno-pmf-conversions. It only works for
2393 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2394 e1 = convert (fntype, e1);
2399 error ("object missing in use of %qE", function);
2400 return error_mark_node;
2404 if (TREE_SIDE_EFFECTS (instance_ptr))
2405 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2407 if (TREE_SIDE_EFFECTS (function))
2408 function = save_expr (function);
2410 /* Start by extracting all the information from the PMF itself. */
2411 e3 = pfn_from_ptrmemfunc (function);
2412 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2413 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2414 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2416 case ptrmemfunc_vbit_in_pfn:
2417 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2418 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2421 case ptrmemfunc_vbit_in_delta:
2422 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2423 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2430 /* Convert down to the right base before using the instance. A
2431 special case is that in a pointer to member of class C, C may
2432 be incomplete. In that case, the function will of course be
2433 a member of C, and no conversion is required. In fact,
2434 lookup_base will fail in that case, because incomplete
2435 classes do not have BINFOs. */
2436 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2437 if (!same_type_ignoring_top_level_qualifiers_p
2438 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2440 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2441 basetype, ba_check, NULL);
2442 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2444 if (instance_ptr == error_mark_node)
2445 return error_mark_node;
2447 /* ...and then the delta in the PMF. */
2448 instance_ptr = build2 (PLUS_EXPR, TREE_TYPE (instance_ptr),
2449 instance_ptr, delta);
2451 /* Hand back the adjusted 'this' argument to our caller. */
2452 *instance_ptrptr = instance_ptr;
2454 /* Next extract the vtable pointer from the object. */
2455 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2457 vtbl = build_indirect_ref (vtbl, NULL);
2459 /* Finally, extract the function pointer from the vtable. */
2460 e2 = fold_build2 (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx);
2461 e2 = build_indirect_ref (e2, NULL);
2462 TREE_CONSTANT (e2) = 1;
2463 TREE_INVARIANT (e2) = 1;
2465 /* When using function descriptors, the address of the
2466 vtable entry is treated as a function pointer. */
2467 if (TARGET_VTABLE_USES_DESCRIPTORS)
2468 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2469 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2471 TREE_TYPE (e2) = TREE_TYPE (e3);
2472 e1 = build_conditional_expr (e1, e2, e3);
2474 /* Make sure this doesn't get evaluated first inside one of the
2475 branches of the COND_EXPR. */
2476 if (instance_save_expr)
2477 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2478 instance_save_expr, e1);
2486 build_function_call (tree function, tree params)
2488 tree fntype, fndecl;
2489 tree coerced_params;
2490 tree name = NULL_TREE;
2492 tree original = function;
2494 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2495 expressions, like those used for ObjC messenger dispatches. */
2496 function = objc_rewrite_function_call (function, params);
2498 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2499 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2500 if (TREE_CODE (function) == NOP_EXPR
2501 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2502 function = TREE_OPERAND (function, 0);
2504 if (TREE_CODE (function) == FUNCTION_DECL)
2506 name = DECL_NAME (function);
2508 mark_used (function);
2511 /* Convert anything with function type to a pointer-to-function. */
2512 if (pedantic && DECL_MAIN_P (function))
2513 pedwarn ("ISO C++ forbids calling %<::main%> from within program");
2515 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2516 (because calling an inline function does not mean the function
2517 needs to be separately compiled). */
2519 if (DECL_INLINE (function))
2520 function = inline_conversion (function);
2522 function = build_addr_func (function);
2528 function = build_addr_func (function);
2531 if (function == error_mark_node)
2532 return error_mark_node;
2534 fntype = TREE_TYPE (function);
2536 if (TYPE_PTRMEMFUNC_P (fntype))
2538 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2539 "function in %<%E (...)%>",
2541 return error_mark_node;
2544 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2545 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2547 if (!((TREE_CODE (fntype) == POINTER_TYPE
2548 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2550 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2552 error ("%qE cannot be used as a function", original);
2553 return error_mark_node;
2556 /* fntype now gets the type of function pointed to. */
2557 fntype = TREE_TYPE (fntype);
2559 /* Convert the parameters to the types declared in the
2560 function prototype, or apply default promotions. */
2562 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2563 params, fndecl, LOOKUP_NORMAL);
2564 if (coerced_params == error_mark_node)
2565 return error_mark_node;
2567 /* Check for errors in format strings and inappropriately
2570 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params,
2571 TYPE_ARG_TYPES (fntype));
2573 return build_cxx_call (function, coerced_params);
2576 /* Convert the actual parameter expressions in the list VALUES
2577 to the types in the list TYPELIST.
2578 If parmdecls is exhausted, or when an element has NULL as its type,
2579 perform the default conversions.
2581 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2583 This is also where warnings about wrong number of args are generated.
2585 Return a list of expressions for the parameters as converted.
2587 Both VALUES and the returned value are chains of TREE_LIST nodes
2588 with the elements of the list in the TREE_VALUE slots of those nodes.
2590 In C++, unspecified trailing parameters can be filled in with their
2591 default arguments, if such were specified. Do so here. */
2594 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2596 tree typetail, valtail;
2597 tree result = NULL_TREE;
2598 const char *called_thing = 0;
2601 /* Argument passing is always copy-initialization. */
2602 flags |= LOOKUP_ONLYCONVERTING;
2606 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2608 if (DECL_NAME (fndecl) == NULL_TREE
2609 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2610 called_thing = "constructor";
2612 called_thing = "member function";
2615 called_thing = "function";
2618 for (valtail = values, typetail = typelist;
2620 valtail = TREE_CHAIN (valtail), i++)
2622 tree type = typetail ? TREE_VALUE (typetail) : 0;
2623 tree val = TREE_VALUE (valtail);
2625 if (val == error_mark_node)
2626 return error_mark_node;
2628 if (type == void_type_node)
2632 error ("too many arguments to %s %q+#D", called_thing, fndecl);
2633 error ("at this point in file");
2636 error ("too many arguments to function");
2637 /* In case anybody wants to know if this argument
2640 TREE_TYPE (tree_last (result)) = error_mark_node;
2644 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2645 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2646 if (TREE_CODE (val) == NOP_EXPR
2647 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2648 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2649 val = TREE_OPERAND (val, 0);
2651 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2653 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2654 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2655 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2656 val = decay_conversion (val);
2659 if (val == error_mark_node)
2660 return error_mark_node;
2664 /* Formal parm type is specified by a function prototype. */
2667 if (!COMPLETE_TYPE_P (complete_type (type)))
2670 error ("parameter %P of %qD has incomplete type %qT",
2673 error ("parameter %P has incomplete type %qT", i, type);
2674 parmval = error_mark_node;
2678 parmval = convert_for_initialization
2679 (NULL_TREE, type, val, flags,
2680 "argument passing", fndecl, i);
2681 parmval = convert_for_arg_passing (type, parmval);
2684 if (parmval == error_mark_node)
2685 return error_mark_node;
2687 result = tree_cons (NULL_TREE, parmval, result);
2691 if (fndecl && DECL_BUILT_IN (fndecl)
2692 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2693 /* Don't do ellipsis conversion for __built_in_constant_p
2694 as this will result in spurious warnings for non-POD
2696 val = require_complete_type (val);
2698 val = convert_arg_to_ellipsis (val);
2700 result = tree_cons (NULL_TREE, val, result);
2704 typetail = TREE_CHAIN (typetail);
2707 if (typetail != 0 && typetail != void_list_node)
2709 /* See if there are default arguments that can be used. */
2710 if (TREE_PURPOSE (typetail)
2711 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2713 for (; typetail != void_list_node; ++i)
2716 = convert_default_arg (TREE_VALUE (typetail),
2717 TREE_PURPOSE (typetail),
2720 if (parmval == error_mark_node)
2721 return error_mark_node;
2723 result = tree_cons (0, parmval, result);
2724 typetail = TREE_CHAIN (typetail);
2725 /* ends with `...'. */
2726 if (typetail == NULL_TREE)
2734 error ("too few arguments to %s %q+#D", called_thing, fndecl);
2735 error ("at this point in file");
2738 error ("too few arguments to function");
2739 return error_mark_list;
2743 return nreverse (result);
2746 /* Build a binary-operation expression, after performing default
2747 conversions on the operands. CODE is the kind of expression to build. */
2750 build_x_binary_op (enum tree_code code, tree arg1, tree arg2,
2760 if (processing_template_decl)
2762 if (type_dependent_expression_p (arg1)
2763 || type_dependent_expression_p (arg2))
2764 return build_min_nt (code, arg1, arg2);
2765 arg1 = build_non_dependent_expr (arg1);
2766 arg2 = build_non_dependent_expr (arg2);
2769 if (code == DOTSTAR_EXPR)
2770 expr = build_m_component_ref (arg1, arg2);
2772 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
2775 if (processing_template_decl && expr != error_mark_node)
2776 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
2781 /* Build a binary-operation expression without default conversions.
2782 CODE is the kind of expression to build.
2783 This function differs from `build' in several ways:
2784 the data type of the result is computed and recorded in it,
2785 warnings are generated if arg data types are invalid,
2786 special handling for addition and subtraction of pointers is known,
2787 and some optimization is done (operations on narrow ints
2788 are done in the narrower type when that gives the same result).
2789 Constant folding is also done before the result is returned.
2791 Note that the operands will never have enumeral types
2792 because either they have just had the default conversions performed
2793 or they have both just been converted to some other type in which
2794 the arithmetic is to be done.
2796 C++: must do special pointer arithmetic when implementing
2797 multiple inheritance, and deal with pointer to member functions. */
2800 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2801 int convert_p ATTRIBUTE_UNUSED)
2804 enum tree_code code0, code1;
2806 const char *invalid_op_diag;
2808 /* Expression code to give to the expression when it is built.
2809 Normally this is CODE, which is what the caller asked for,
2810 but in some special cases we change it. */
2811 enum tree_code resultcode = code;
2813 /* Data type in which the computation is to be performed.
2814 In the simplest cases this is the common type of the arguments. */
2815 tree result_type = NULL;
2817 /* Nonzero means operands have already been type-converted
2818 in whatever way is necessary.
2819 Zero means they need to be converted to RESULT_TYPE. */
2822 /* Nonzero means create the expression with this type, rather than
2824 tree build_type = 0;
2826 /* Nonzero means after finally constructing the expression
2827 convert it to this type. */
2828 tree final_type = 0;
2832 /* Nonzero if this is an operation like MIN or MAX which can
2833 safely be computed in short if both args are promoted shorts.
2834 Also implies COMMON.
2835 -1 indicates a bitwise operation; this makes a difference
2836 in the exact conditions for when it is safe to do the operation
2837 in a narrower mode. */
2840 /* Nonzero if this is a comparison operation;
2841 if both args are promoted shorts, compare the original shorts.
2842 Also implies COMMON. */
2843 int short_compare = 0;
2845 /* Nonzero if this is a right-shift operation, which can be computed on the
2846 original short and then promoted if the operand is a promoted short. */
2847 int short_shift = 0;
2849 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2852 /* True if both operands have arithmetic type. */
2853 bool arithmetic_types_p;
2855 /* Apply default conversions. */
2859 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2860 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2861 || code == TRUTH_XOR_EXPR)
2863 if (!really_overloaded_fn (op0))
2864 op0 = decay_conversion (op0);
2865 if (!really_overloaded_fn (op1))
2866 op1 = decay_conversion (op1);
2870 if (!really_overloaded_fn (op0))
2871 op0 = default_conversion (op0);
2872 if (!really_overloaded_fn (op1))
2873 op1 = default_conversion (op1);
2876 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2877 STRIP_TYPE_NOPS (op0);
2878 STRIP_TYPE_NOPS (op1);
2880 /* DTRT if one side is an overloaded function, but complain about it. */
2881 if (type_unknown_p (op0))
2883 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
2884 if (t != error_mark_node)
2886 pedwarn ("assuming cast to type %qT from overloaded function",
2891 if (type_unknown_p (op1))
2893 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
2894 if (t != error_mark_node)
2896 pedwarn ("assuming cast to type %qT from overloaded function",
2902 type0 = TREE_TYPE (op0);
2903 type1 = TREE_TYPE (op1);
2905 /* The expression codes of the data types of the arguments tell us
2906 whether the arguments are integers, floating, pointers, etc. */
2907 code0 = TREE_CODE (type0);
2908 code1 = TREE_CODE (type1);
2910 /* If an error was already reported for one of the arguments,
2911 avoid reporting another error. */
2913 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
2914 return error_mark_node;
2916 if ((invalid_op_diag
2917 = targetm.invalid_binary_op (code, type0, type1)))
2919 error (invalid_op_diag);
2920 return error_mark_node;
2926 /* Handle the pointer + int case. */
2927 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2928 return cp_pointer_int_sum (PLUS_EXPR, op0, op1);
2929 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
2930 return cp_pointer_int_sum (PLUS_EXPR, op1, op0);
2936 /* Subtraction of two similar pointers.
2937 We must subtract them as integers, then divide by object size. */
2938 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
2939 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
2941 return pointer_diff (op0, op1, common_type (type0, type1));
2942 /* Handle pointer minus int. Just like pointer plus int. */
2943 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2944 return cp_pointer_int_sum (MINUS_EXPR, op0, op1);
2953 case TRUNC_DIV_EXPR:
2955 case FLOOR_DIV_EXPR:
2956 case ROUND_DIV_EXPR:
2957 case EXACT_DIV_EXPR:
2958 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2959 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
2960 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2961 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
2963 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
2964 warning (0, "division by zero in %<%E / 0%>", op0);
2965 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
2966 warning (0, "division by zero in %<%E / 0.%>", op0);
2968 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
2969 code0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
2970 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
2971 code1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
2973 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
2974 resultcode = RDIV_EXPR;
2976 /* When dividing two signed integers, we have to promote to int.
2977 unless we divide by a constant != -1. Note that default
2978 conversion will have been performed on the operands at this
2979 point, so we have to dig out the original type to find out if
2981 shorten = ((TREE_CODE (op0) == NOP_EXPR
2982 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2983 || (TREE_CODE (op1) == INTEGER_CST
2984 && ! integer_all_onesp (op1)));
2993 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2994 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE))
2998 case TRUNC_MOD_EXPR:
2999 case FLOOR_MOD_EXPR:
3000 if (code1 == INTEGER_TYPE && integer_zerop (op1))
3001 warning (0, "division by zero in %<%E %% 0%>", op0);
3002 else if (code1 == REAL_TYPE && real_zerop (op1))
3003 warning (0, "division by zero in %<%E %% 0.%>", op0);
3005 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3007 /* Although it would be tempting to shorten always here, that loses
3008 on some targets, since the modulo instruction is undefined if the
3009 quotient can't be represented in the computation mode. We shorten
3010 only if unsigned or if dividing by something we know != -1. */
3011 shorten = ((TREE_CODE (op0) == NOP_EXPR
3012 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3013 || (TREE_CODE (op1) == INTEGER_CST
3014 && ! integer_all_onesp (op1)));
3019 case TRUTH_ANDIF_EXPR:
3020 case TRUTH_ORIF_EXPR:
3021 case TRUTH_AND_EXPR:
3023 result_type = boolean_type_node;
3026 /* Shift operations: result has same type as first operand;
3027 always convert second operand to int.
3028 Also set SHORT_SHIFT if shifting rightward. */
3031 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3033 result_type = type0;
3034 if (TREE_CODE (op1) == INTEGER_CST)
3036 if (tree_int_cst_lt (op1, integer_zero_node))
3037 warning (0, "right shift count is negative");
3040 if (! integer_zerop (op1))
3042 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3043 warning (0, "right shift count >= width of type");
3046 /* Convert the shift-count to an integer, regardless of
3047 size of value being shifted. */
3048 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3049 op1 = cp_convert (integer_type_node, op1);
3050 /* Avoid converting op1 to result_type later. */
3056 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3058 result_type = type0;
3059 if (TREE_CODE (op1) == INTEGER_CST)
3061 if (tree_int_cst_lt (op1, integer_zero_node))
3062 warning (0, "left shift count is negative");
3063 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3064 warning (0, "left shift count >= width of type");
3066 /* Convert the shift-count to an integer, regardless of
3067 size of value being shifted. */
3068 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3069 op1 = cp_convert (integer_type_node, op1);
3070 /* Avoid converting op1 to result_type later. */
3077 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3079 result_type = type0;
3080 if (TREE_CODE (op1) == INTEGER_CST)
3082 if (tree_int_cst_lt (op1, integer_zero_node))
3083 warning (0, "%s rotate count is negative",
3084 (code == LROTATE_EXPR) ? "left" : "right");
3085 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3086 warning (0, "%s rotate count >= width of type",
3087 (code == LROTATE_EXPR) ? "left" : "right");
3089 /* Convert the shift-count to an integer, regardless of
3090 size of value being shifted. */
3091 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3092 op1 = cp_convert (integer_type_node, op1);
3098 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
3099 warning (0, "comparing floating point with == or != is unsafe");
3101 build_type = boolean_type_node;
3102 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3103 || code0 == COMPLEX_TYPE)
3104 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3105 || code1 == COMPLEX_TYPE))
3107 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3108 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3109 result_type = composite_pointer_type (type0, type1, op0, op1,
3111 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3112 && null_ptr_cst_p (op1))
3113 result_type = type0;
3114 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3115 && null_ptr_cst_p (op0))
3116 result_type = type1;
3117 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3119 result_type = type0;
3120 error ("ISO C++ forbids comparison between pointer and integer");
3122 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3124 result_type = type1;
3125 error ("ISO C++ forbids comparison between pointer and integer");
3127 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3129 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3130 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3131 result_type = TREE_TYPE (op0);
3133 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3134 return cp_build_binary_op (code, op1, op0);
3135 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
3136 && same_type_p (type0, type1))
3138 /* E will be the final comparison. */
3140 /* E1 and E2 are for scratch. */
3148 if (TREE_SIDE_EFFECTS (op0))
3149 op0 = save_expr (op0);
3150 if (TREE_SIDE_EFFECTS (op1))
3151 op1 = save_expr (op1);
3156 && (!op0.pfn || op0.delta == op1.delta))
3158 The reason for the `!op0.pfn' bit is that a NULL
3159 pointer-to-member is any member with a zero PFN; the
3160 DELTA field is unspecified. */
3161 pfn0 = pfn_from_ptrmemfunc (op0);
3162 pfn1 = pfn_from_ptrmemfunc (op1);
3163 delta0 = build_ptrmemfunc_access_expr (op0,
3165 delta1 = build_ptrmemfunc_access_expr (op1,
3167 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
3168 e2 = cp_build_binary_op (EQ_EXPR,
3170 cp_convert (TREE_TYPE (pfn0),
3171 integer_zero_node));
3172 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
3173 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3174 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3175 if (code == EQ_EXPR)
3177 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3181 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3182 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3184 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3185 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3193 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3194 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3196 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3197 result_type = composite_pointer_type (type0, type1, op0, op1,
3205 build_type = boolean_type_node;
3206 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3207 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3209 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3210 result_type = composite_pointer_type (type0, type1, op0, op1,
3212 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3213 && integer_zerop (op1))
3214 result_type = type0;
3215 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3216 && integer_zerop (op0))
3217 result_type = type1;
3218 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3220 result_type = type0;
3221 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3223 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3225 result_type = type1;
3226 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3230 case UNORDERED_EXPR:
3237 build_type = integer_type_node;
3238 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3240 error ("unordered comparison on non-floating point argument");
3241 return error_mark_node;
3250 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3251 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3252 || code1 == COMPLEX_TYPE)))
3253 arithmetic_types_p = 1;
3256 arithmetic_types_p = 0;
3257 /* Vector arithmetic is only allowed when both sides are vectors. */
3258 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3260 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3261 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3264 binary_op_error (code);
3265 return error_mark_node;
3267 arithmetic_types_p = 1;
3270 /* Determine the RESULT_TYPE, if it is not already known. */
3272 && arithmetic_types_p
3273 && (shorten || common || short_compare))
3274 result_type = common_type (type0, type1);
3278 error ("invalid operands of types %qT and %qT to binary %qO",
3279 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3280 return error_mark_node;
3283 /* If we're in a template, the only thing we need to know is the
3285 if (processing_template_decl)
3286 return build2 (resultcode,
3287 build_type ? build_type : result_type,
3290 if (arithmetic_types_p)
3292 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3294 /* For certain operations (which identify themselves by shorten != 0)
3295 if both args were extended from the same smaller type,
3296 do the arithmetic in that type and then extend.
3298 shorten !=0 and !=1 indicates a bitwise operation.
3299 For them, this optimization is safe only if
3300 both args are zero-extended or both are sign-extended.
3301 Otherwise, we might change the result.
3302 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3303 but calculated in (unsigned short) it would be (unsigned short)-1. */
3305 if (shorten && none_complex)
3307 int unsigned0, unsigned1;
3308 tree arg0 = get_narrower (op0, &unsigned0);
3309 tree arg1 = get_narrower (op1, &unsigned1);
3310 /* UNS is 1 if the operation to be done is an unsigned one. */
3311 int uns = TYPE_UNSIGNED (result_type);
3314 final_type = result_type;
3316 /* Handle the case that OP0 does not *contain* a conversion
3317 but it *requires* conversion to FINAL_TYPE. */
3319 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3320 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
3321 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3322 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
3324 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3326 /* For bitwise operations, signedness of nominal type
3327 does not matter. Consider only how operands were extended. */
3331 /* Note that in all three cases below we refrain from optimizing
3332 an unsigned operation on sign-extended args.
3333 That would not be valid. */
3335 /* Both args variable: if both extended in same way
3336 from same width, do it in that width.
3337 Do it unsigned if args were zero-extended. */
3338 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3339 < TYPE_PRECISION (result_type))
3340 && (TYPE_PRECISION (TREE_TYPE (arg1))
3341 == TYPE_PRECISION (TREE_TYPE (arg0)))
3342 && unsigned0 == unsigned1
3343 && (unsigned0 || !uns))
3344 result_type = c_common_signed_or_unsigned_type
3345 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3346 else if (TREE_CODE (arg0) == INTEGER_CST
3347 && (unsigned1 || !uns)
3348 && (TYPE_PRECISION (TREE_TYPE (arg1))
3349 < TYPE_PRECISION (result_type))
3350 && (type = c_common_signed_or_unsigned_type
3351 (unsigned1, TREE_TYPE (arg1)),
3352 int_fits_type_p (arg0, type)))
3354 else if (TREE_CODE (arg1) == INTEGER_CST
3355 && (unsigned0 || !uns)
3356 && (TYPE_PRECISION (TREE_TYPE (arg0))
3357 < TYPE_PRECISION (result_type))
3358 && (type = c_common_signed_or_unsigned_type
3359 (unsigned0, TREE_TYPE (arg0)),
3360 int_fits_type_p (arg1, type)))
3364 /* Shifts can be shortened if shifting right. */
3369 tree arg0 = get_narrower (op0, &unsigned_arg);
3371 final_type = result_type;
3373 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3374 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
3376 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3377 /* We can shorten only if the shift count is less than the
3378 number of bits in the smaller type size. */
3379 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3380 /* If arg is sign-extended and then unsigned-shifted,
3381 we can simulate this with a signed shift in arg's type
3382 only if the extended result is at least twice as wide
3383 as the arg. Otherwise, the shift could use up all the
3384 ones made by sign-extension and bring in zeros.
3385 We can't optimize that case at all, but in most machines
3386 it never happens because available widths are 2**N. */
3387 && (!TYPE_UNSIGNED (final_type)
3389 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3390 <= TYPE_PRECISION (result_type))))
3392 /* Do an unsigned shift if the operand was zero-extended. */
3394 = c_common_signed_or_unsigned_type (unsigned_arg,
3396 /* Convert value-to-be-shifted to that type. */
3397 if (TREE_TYPE (op0) != result_type)
3398 op0 = cp_convert (result_type, op0);
3403 /* Comparison operations are shortened too but differently.
3404 They identify themselves by setting short_compare = 1. */
3408 /* Don't write &op0, etc., because that would prevent op0
3409 from being kept in a register.
3410 Instead, make copies of the our local variables and
3411 pass the copies by reference, then copy them back afterward. */
3412 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3413 enum tree_code xresultcode = resultcode;
3415 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3417 return cp_convert (boolean_type_node, val);
3418 op0 = xop0, op1 = xop1;
3420 resultcode = xresultcode;
3423 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3424 && warn_sign_compare
3425 /* Do not warn until the template is instantiated; we cannot
3426 bound the ranges of the arguments until that point. */
3427 && !processing_template_decl)
3429 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
3430 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3432 int unsignedp0, unsignedp1;
3433 tree primop0 = get_narrower (op0, &unsignedp0);
3434 tree primop1 = get_narrower (op1, &unsignedp1);
3436 /* Check for comparison of different enum types. */
3437 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3438 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3439 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3440 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3442 warning (0, "comparison between types %q#T and %q#T",
3443 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3446 /* Give warnings for comparisons between signed and unsigned
3447 quantities that may fail. */
3448 /* Do the checking based on the original operand trees, so that
3449 casts will be considered, but default promotions won't be. */
3451 /* Do not warn if the comparison is being done in a signed type,
3452 since the signed type will only be chosen if it can represent
3453 all the values of the unsigned type. */
3454 if (!TYPE_UNSIGNED (result_type))
3456 /* Do not warn if both operands are unsigned. */
3457 else if (op0_signed == op1_signed)
3459 /* Do not warn if the signed quantity is an unsuffixed
3460 integer literal (or some static constant expression
3461 involving such literals or a conditional expression
3462 involving such literals) and it is non-negative. */
3463 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3464 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3466 /* Do not warn if the comparison is an equality operation,
3467 the unsigned quantity is an integral constant and it does
3468 not use the most significant bit of result_type. */
3469 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3470 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3471 && int_fits_type_p (orig_op1, c_common_signed_type
3473 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3474 && int_fits_type_p (orig_op0, c_common_signed_type
3478 warning (0, "comparison between signed and unsigned integer expressions");
3480 /* Warn if two unsigned values are being compared in a size
3481 larger than their original size, and one (and only one) is the
3482 result of a `~' operator. This comparison will always fail.
3484 Also warn if one operand is a constant, and the constant does not
3485 have all bits set that are set in the ~ operand when it is
3488 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3489 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3491 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3492 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3493 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3494 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3496 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3499 HOST_WIDE_INT constant, mask;
3503 if (host_integerp (primop0, 0))
3506 unsignedp = unsignedp1;
3507 constant = tree_low_cst (primop0, 0);
3512 unsignedp = unsignedp0;
3513 constant = tree_low_cst (primop1, 0);
3516 bits = TYPE_PRECISION (TREE_TYPE (primop));
3517 if (bits < TYPE_PRECISION (result_type)
3518 && bits < HOST_BITS_PER_LONG && unsignedp)
3520 mask = (~ (HOST_WIDE_INT) 0) << bits;
3521 if ((mask & constant) != mask)
3522 warning (0, "comparison of promoted ~unsigned with constant");
3525 else if (unsignedp0 && unsignedp1
3526 && (TYPE_PRECISION (TREE_TYPE (primop0))
3527 < TYPE_PRECISION (result_type))
3528 && (TYPE_PRECISION (TREE_TYPE (primop1))
3529 < TYPE_PRECISION (result_type)))
3530 warning (0, "comparison of promoted ~unsigned with unsigned");
3535 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3536 Then the expression will be built.
3537 It will be given type FINAL_TYPE if that is nonzero;
3538 otherwise, it will be given type RESULT_TYPE. */
3540 /* Issue warnings about peculiar, but valid, uses of NULL. */
3541 if (/* It's reasonable to use pointer values as operands of &&
3542 and ||, so NULL is no exception. */
3543 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3544 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3545 (orig_op0 == null_node
3546 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3547 /* Or vice versa. */
3548 || (orig_op1 == null_node
3549 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3550 /* Or, both are NULL and the operation was not a comparison. */
3551 || (orig_op0 == null_node && orig_op1 == null_node
3552 && code != EQ_EXPR && code != NE_EXPR)))
3553 /* Some sort of arithmetic operation involving NULL was
3554 performed. Note that pointer-difference and pointer-addition
3555 have already been handled above, and so we don't end up here in
3557 warning (0, "NULL used in arithmetic");
3561 if (TREE_TYPE (op0) != result_type)
3562 op0 = cp_convert (result_type, op0);
3563 if (TREE_TYPE (op1) != result_type)
3564 op1 = cp_convert (result_type, op1);
3566 if (op0 == error_mark_node || op1 == error_mark_node)
3567 return error_mark_node;
3570 if (build_type == NULL_TREE)
3571 build_type = result_type;
3573 result = build2 (resultcode, build_type, op0, op1);
3574 result = fold_if_not_in_template (result);
3575 if (final_type != 0)
3576 result = cp_convert (final_type, result);
3580 /* Return a tree for the sum or difference (RESULTCODE says which)
3581 of pointer PTROP and integer INTOP. */
3584 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
3586 tree res_type = TREE_TYPE (ptrop);
3588 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3589 in certain circumstance (when it's valid to do so). So we need
3590 to make sure it's complete. We don't need to check here, if we
3591 can actually complete it at all, as those checks will be done in
3592 pointer_int_sum() anyway. */
3593 complete_type (TREE_TYPE (res_type));
3595 return pointer_int_sum (resultcode, ptrop,
3596 fold_if_not_in_template (intop));
3599 /* Return a tree for the difference of pointers OP0 and OP1.
3600 The resulting tree has type int. */
3603 pointer_diff (tree op0, tree op1, tree ptrtype)
3606 tree restype = ptrdiff_type_node;
3607 tree target_type = TREE_TYPE (ptrtype);
3609 if (!complete_type_or_else (target_type, NULL_TREE))
3610 return error_mark_node;
3612 if (pedantic || warn_pointer_arith)
3614 if (TREE_CODE (target_type) == VOID_TYPE)
3615 pedwarn ("ISO C++ forbids using pointer of type %<void *%> in subtraction");
3616 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3617 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3618 if (TREE_CODE (target_type) == METHOD_TYPE)
3619 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3622 /* First do the subtraction as integers;
3623 then drop through to build the divide operator. */
3625 op0 = cp_build_binary_op (MINUS_EXPR,
3626 cp_convert (restype, op0),
3627 cp_convert (restype, op1));
3629 /* This generates an error if op1 is a pointer to an incomplete type. */
3630 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3631 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3633 op1 = (TYPE_PTROB_P (ptrtype)
3634 ? size_in_bytes (target_type)
3635 : integer_one_node);
3637 /* Do the division. */
3639 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3640 return fold_if_not_in_template (result);
3643 /* Construct and perhaps optimize a tree representation
3644 for a unary operation. CODE, a tree_code, specifies the operation
3645 and XARG is the operand. */
3648 build_x_unary_op (enum tree_code code, tree xarg)
3650 tree orig_expr = xarg;
3654 if (processing_template_decl)
3656 if (type_dependent_expression_p (xarg))
3657 return build_min_nt (code, xarg, NULL_TREE);
3659 xarg = build_non_dependent_expr (xarg);
3664 /* [expr.unary.op] says:
3666 The address of an object of incomplete type can be taken.
3668 (And is just the ordinary address operator, not an overloaded
3669 "operator &".) However, if the type is a template
3670 specialization, we must complete the type at this point so that
3671 an overloaded "operator &" will be available if required. */
3672 if (code == ADDR_EXPR
3673 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3674 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
3675 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
3676 || (TREE_CODE (xarg) == OFFSET_REF)))
3677 /* Don't look for a function. */;
3679 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
3680 /*overloaded_p=*/NULL);
3681 if (!exp && code == ADDR_EXPR)
3683 /* A pointer to member-function can be formed only by saying
3685 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3686 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3688 if (TREE_CODE (xarg) != OFFSET_REF
3689 || !TYPE_P (TREE_OPERAND (xarg, 0)))
3691 error ("invalid use of %qE to form a pointer-to-member-function",
3693 if (TREE_CODE (xarg) != OFFSET_REF)
3694 inform (" a qualified-id is required");
3695 return error_mark_node;
3699 error ("parenthesis around %qE cannot be used to form a"
3700 " pointer-to-member-function",
3702 PTRMEM_OK_P (xarg) = 1;
3706 if (TREE_CODE (xarg) == OFFSET_REF)
3708 ptrmem = PTRMEM_OK_P (xarg);
3710 if (!ptrmem && !flag_ms_extensions
3711 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3713 /* A single non-static member, make sure we don't allow a
3714 pointer-to-member. */
3715 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
3716 TREE_OPERAND (xarg, 0),
3717 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3718 PTRMEM_OK_P (xarg) = ptrmem;
3721 else if (TREE_CODE (xarg) == TARGET_EXPR)
3722 warning (0, "taking address of temporary");
3723 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3726 if (processing_template_decl && exp != error_mark_node)
3727 exp = build_min_non_dep (code, exp, orig_expr,
3728 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
3729 if (TREE_CODE (exp) == ADDR_EXPR)
3730 PTRMEM_OK_P (exp) = ptrmem;
3734 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3735 constants, where a null value is represented by an INTEGER_CST of
3739 cp_truthvalue_conversion (tree expr)
3741 tree type = TREE_TYPE (expr);
3742 if (TYPE_PTRMEM_P (type))
3743 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3745 return c_common_truthvalue_conversion (expr);
3748 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3751 condition_conversion (tree expr)
3754 if (processing_template_decl)
3756 t = perform_implicit_conversion (boolean_type_node, expr);
3757 t = fold_build_cleanup_point_expr (boolean_type_node, t);
3761 /* Return an ADDR_EXPR giving the address of T. This function
3762 attempts no optimizations or simplifications; it is a low-level
3766 build_address (tree t)
3770 if (error_operand_p (t) || !cxx_mark_addressable (t))
3771 return error_mark_node;
3773 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
3778 /* Return a NOP_EXPR converting EXPR to TYPE. */
3781 build_nop (tree type, tree expr)
3783 if (type == error_mark_node || error_operand_p (expr))
3785 return build1 (NOP_EXPR, type, expr);
3788 /* C++: Must handle pointers to members.
3790 Perhaps type instantiation should be extended to handle conversion
3791 from aggregates to types we don't yet know we want? (Or are those
3792 cases typically errors which should be reported?)
3794 NOCONVERT nonzero suppresses the default promotions
3795 (such as from short to int). */
3798 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3800 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3803 const char *errstring = NULL;
3805 const char *invalid_op_diag;
3807 if (arg == error_mark_node)
3808 return error_mark_node;
3810 if ((invalid_op_diag
3811 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
3816 error (invalid_op_diag);
3817 return error_mark_node;
3822 case UNARY_PLUS_EXPR:
3825 int flags = WANT_ARITH | WANT_ENUM;
3826 /* Unary plus (but not unary minus) is allowed on pointers. */
3827 if (code == UNARY_PLUS_EXPR)
3828 flags |= WANT_POINTER;
3829 arg = build_expr_type_conversion (flags, arg, true);
3831 errstring = (code == NEGATE_EXPR
3832 ? "wrong type argument to unary minus"
3833 : "wrong type argument to unary plus");
3836 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3837 arg = perform_integral_promotions (arg);
3839 /* Make sure the result is not an lvalue: a unary plus or minus
3840 expression is always a rvalue. */
3847 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3851 arg = default_conversion (arg);
3853 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
3855 errstring = "wrong type argument to bit-complement";
3856 else if (!noconvert)
3857 arg = perform_integral_promotions (arg);
3861 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3862 errstring = "wrong type argument to abs";
3863 else if (!noconvert)
3864 arg = default_conversion (arg);
3868 /* Conjugating a real value is a no-op, but allow it anyway. */
3869 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3870 errstring = "wrong type argument to conjugation";
3871 else if (!noconvert)
3872 arg = default_conversion (arg);
3875 case TRUTH_NOT_EXPR:
3876 arg = perform_implicit_conversion (boolean_type_node, arg);
3877 val = invert_truthvalue (arg);
3878 if (arg != error_mark_node)
3880 errstring = "in argument to unary !";
3887 if (TREE_CODE (arg) == COMPLEX_CST)
3888 return TREE_REALPART (arg);
3889 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3891 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3892 return fold_if_not_in_template (arg);
3898 if (TREE_CODE (arg) == COMPLEX_CST)
3899 return TREE_IMAGPART (arg);
3900 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3902 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3903 return fold_if_not_in_template (arg);
3906 return cp_convert (TREE_TYPE (arg), integer_zero_node);
3908 case PREINCREMENT_EXPR:
3909 case POSTINCREMENT_EXPR:
3910 case PREDECREMENT_EXPR:
3911 case POSTDECREMENT_EXPR:
3912 /* Handle complex lvalues (when permitted)
3913 by reduction to simpler cases. */
3915 val = unary_complex_lvalue (code, arg);
3919 /* Increment or decrement the real part of the value,
3920 and don't change the imaginary part. */
3921 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3925 arg = stabilize_reference (arg);
3926 real = build_unary_op (REALPART_EXPR, arg, 1);
3927 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
3928 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
3929 build_unary_op (code, real, 1), imag);
3932 /* Report invalid types. */
3934 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
3937 if (code == PREINCREMENT_EXPR)
3938 errstring ="no pre-increment operator for type";
3939 else if (code == POSTINCREMENT_EXPR)
3940 errstring ="no post-increment operator for type";
3941 else if (code == PREDECREMENT_EXPR)
3942 errstring ="no pre-decrement operator for type";
3944 errstring ="no post-decrement operator for type";
3948 /* Report something read-only. */
3950 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
3951 || TREE_READONLY (arg))
3952 readonly_error (arg, ((code == PREINCREMENT_EXPR
3953 || code == POSTINCREMENT_EXPR)
3954 ? "increment" : "decrement"),
3959 tree result_type = TREE_TYPE (arg);
3961 arg = get_unwidened (arg, 0);
3962 argtype = TREE_TYPE (arg);
3964 /* ARM $5.2.5 last annotation says this should be forbidden. */
3965 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
3966 pedwarn ("ISO C++ forbids %sing an enum",
3967 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3968 ? "increment" : "decrement");
3970 /* Compute the increment. */
3972 if (TREE_CODE (argtype) == POINTER_TYPE)
3974 tree type = complete_type (TREE_TYPE (argtype));
3976 if (!COMPLETE_OR_VOID_TYPE_P (type))
3977 error ("cannot %s a pointer to incomplete type %qT",
3978 ((code == PREINCREMENT_EXPR
3979 || code == POSTINCREMENT_EXPR)
3980 ? "increment" : "decrement"), TREE_TYPE (argtype));
3981 else if ((pedantic || warn_pointer_arith)
3982 && !TYPE_PTROB_P (argtype))
3983 pedwarn ("ISO C++ forbids %sing a pointer of type %qT",
3984 ((code == PREINCREMENT_EXPR
3985 || code == POSTINCREMENT_EXPR)
3986 ? "increment" : "decrement"), argtype);
3987 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
3990 inc = integer_one_node;
3992 inc = cp_convert (argtype, inc);
3994 /* Handle incrementing a cast-expression. */
3996 switch (TREE_CODE (arg))
4001 case FIX_TRUNC_EXPR:
4002 case FIX_FLOOR_EXPR:
4003 case FIX_ROUND_EXPR:
4006 tree incremented, modify, value, compound;
4007 if (! lvalue_p (arg) && pedantic)
4008 pedwarn ("cast to non-reference type used as lvalue");
4009 arg = stabilize_reference (arg);
4010 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
4013 value = save_expr (arg);
4014 incremented = build2 (((code == PREINCREMENT_EXPR
4015 || code == POSTINCREMENT_EXPR)
4016 ? PLUS_EXPR : MINUS_EXPR),
4017 argtype, value, inc);
4019 modify = build_modify_expr (arg, NOP_EXPR, incremented);
4020 compound = build2 (COMPOUND_EXPR, TREE_TYPE (arg),
4023 /* Eliminate warning about unused result of + or -. */
4024 TREE_NO_WARNING (compound) = 1;
4032 /* Complain about anything else that is not a true lvalue. */
4033 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4034 || code == POSTINCREMENT_EXPR)
4035 ? lv_increment : lv_decrement)))
4036 return error_mark_node;
4038 /* Forbid using -- on `bool'. */
4039 if (TREE_TYPE (arg) == boolean_type_node)
4041 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4043 error ("invalid use of %<--%> on bool variable %qD", arg);
4044 return error_mark_node;
4046 val = boolean_increment (code, arg);
4049 val = build2 (code, TREE_TYPE (arg), arg, inc);
4051 TREE_SIDE_EFFECTS (val) = 1;
4052 return cp_convert (result_type, val);
4056 /* Note that this operation never does default_conversion
4057 regardless of NOCONVERT. */
4059 argtype = lvalue_type (arg);
4061 if (TREE_CODE (arg) == OFFSET_REF)
4064 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4066 tree type = build_pointer_type (TREE_TYPE (argtype));
4067 arg = build1 (CONVERT_EXPR, type, arg);
4070 else if (pedantic && DECL_MAIN_P (arg))
4072 pedwarn ("ISO C++ forbids taking address of function %<::main%>");
4074 /* Let &* cancel out to simplify resulting code. */
4075 if (TREE_CODE (arg) == INDIRECT_REF)
4077 /* We don't need to have `current_class_ptr' wrapped in a
4078 NON_LVALUE_EXPR node. */
4079 if (arg == current_class_ref)
4080 return current_class_ptr;
4082 arg = TREE_OPERAND (arg, 0);
4083 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4085 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4086 arg = build1 (CONVERT_EXPR, type, arg);
4089 /* Don't let this be an lvalue. */
4094 /* Uninstantiated types are all functions. Taking the
4095 address of a function is a no-op, so just return the
4098 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4099 || !IDENTIFIER_OPNAME_P (arg));
4101 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4102 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4104 /* They're trying to take the address of a unique non-static
4105 member function. This is ill-formed (except in MS-land),
4106 but let's try to DTRT.
4107 Note: We only handle unique functions here because we don't
4108 want to complain if there's a static overload; non-unique
4109 cases will be handled by instantiate_type. But we need to
4110 handle this case here to allow casts on the resulting PMF.
4111 We could defer this in non-MS mode, but it's easier to give
4112 a useful error here. */
4114 /* Inside constant member functions, the `this' pointer
4115 contains an extra const qualifier. TYPE_MAIN_VARIANT
4116 is used here to remove this const from the diagnostics
4117 and the created OFFSET_REF. */
4118 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4119 tree name = DECL_NAME (get_first_fn (TREE_OPERAND (arg, 1)));
4121 if (! flag_ms_extensions)
4123 if (current_class_type
4124 && TREE_OPERAND (arg, 0) == current_class_ref)
4125 /* An expression like &memfn. */
4126 pedwarn ("ISO C++ forbids taking the address of an unqualified"
4127 " or parenthesized non-static member function to form"
4128 " a pointer to member function. Say %<&%T::%D%>",
4131 pedwarn ("ISO C++ forbids taking the address of a bound member"
4132 " function to form a pointer to member function."
4136 arg = build_offset_ref (base, name, /*address_p=*/true);
4140 if (type_unknown_p (arg))
4141 return build1 (ADDR_EXPR, unknown_type_node, arg);
4143 /* Handle complex lvalues (when permitted)
4144 by reduction to simpler cases. */
4145 val = unary_complex_lvalue (code, arg);
4149 switch (TREE_CODE (arg))
4154 case FIX_TRUNC_EXPR:
4155 case FIX_FLOOR_EXPR:
4156 case FIX_ROUND_EXPR:
4158 if (! lvalue_p (arg) && pedantic)
4159 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4163 arg = OVL_CURRENT (arg);
4167 /* Turn a reference to a non-static data member into a
4168 pointer-to-member. */
4173 if (!PTRMEM_OK_P (arg))
4174 return build_unary_op (code, arg, 0);
4176 t = TREE_OPERAND (arg, 1);
4177 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4179 error ("cannot create pointer to reference member %qD", t);
4180 return error_mark_node;
4183 type = build_ptrmem_type (context_for_name_lookup (t),
4185 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4193 /* Allow the address of a constructor if all the elements
4195 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_HAS_CONSTRUCTOR (arg)
4196 && TREE_CONSTANT (arg))
4198 /* Anything not already handled and not a true memory reference
4200 else if (TREE_CODE (argtype) != FUNCTION_TYPE
4201 && TREE_CODE (argtype) != METHOD_TYPE
4202 && TREE_CODE (arg) != OFFSET_REF
4203 && !lvalue_or_else (arg, lv_addressof))
4204 return error_mark_node;
4206 if (argtype != error_mark_node)
4207 argtype = build_pointer_type (argtype);
4212 if (TREE_CODE (arg) != COMPONENT_REF
4213 /* Inside a template, we are processing a non-dependent
4214 expression so we can just form an ADDR_EXPR with the
4216 || processing_template_decl)
4218 addr = build_address (arg);
4219 if (TREE_CODE (arg) == OFFSET_REF)
4220 PTRMEM_OK_P (addr) = PTRMEM_OK_P (arg);
4222 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4224 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4226 /* We can only get here with a single static member
4228 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4229 && DECL_STATIC_FUNCTION_P (fn));
4231 addr = build_address (fn);
4232 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4233 /* Do not lose object's side effects. */
4234 addr = build2 (COMPOUND_EXPR, TREE_TYPE (addr),
4235 TREE_OPERAND (arg, 0), addr);
4237 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4239 error ("attempt to take address of bit-field structure member %qD",
4240 TREE_OPERAND (arg, 1));
4241 return error_mark_node;
4245 tree object = TREE_OPERAND (arg, 0);
4246 tree field = TREE_OPERAND (arg, 1);
4247 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4248 (TREE_TYPE (object), decl_type_context (field)));
4249 addr = build_address (arg);
4252 if (TREE_CODE (argtype) == POINTER_TYPE
4253 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4255 build_ptrmemfunc_type (argtype);
4256 addr = build_ptrmemfunc (argtype, addr, 0,
4257 /*c_cast_p=*/false);
4270 argtype = TREE_TYPE (arg);
4271 return fold_if_not_in_template (build1 (code, argtype, arg));
4274 error ("%s", errstring);
4275 return error_mark_node;
4278 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4279 for certain kinds of expressions which are not really lvalues
4280 but which we can accept as lvalues.
4282 If ARG is not a kind of expression we can handle, return
4286 unary_complex_lvalue (enum tree_code code, tree arg)
4288 /* Inside a template, making these kinds of adjustments is
4289 pointless; we are only concerned with the type of the
4291 if (processing_template_decl)
4294 /* Handle (a, b) used as an "lvalue". */
4295 if (TREE_CODE (arg) == COMPOUND_EXPR)
4297 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4298 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4299 TREE_OPERAND (arg, 0), real_result);
4302 /* Handle (a ? b : c) used as an "lvalue". */
4303 if (TREE_CODE (arg) == COND_EXPR
4304 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4305 return rationalize_conditional_expr (code, arg);
4307 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4308 if (TREE_CODE (arg) == MODIFY_EXPR
4309 || TREE_CODE (arg) == PREINCREMENT_EXPR
4310 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4312 tree lvalue = TREE_OPERAND (arg, 0);
4313 if (TREE_SIDE_EFFECTS (lvalue))
4315 lvalue = stabilize_reference (lvalue);
4316 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4317 lvalue, TREE_OPERAND (arg, 1));
4319 return unary_complex_lvalue
4320 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4323 if (code != ADDR_EXPR)
4326 /* Handle (a = b) used as an "lvalue" for `&'. */
4327 if (TREE_CODE (arg) == MODIFY_EXPR
4328 || TREE_CODE (arg) == INIT_EXPR)
4330 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4331 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4333 TREE_NO_WARNING (arg) = 1;
4337 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4338 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4339 || TREE_CODE (arg) == OFFSET_REF)
4342 /* We permit compiler to make function calls returning
4343 objects of aggregate type look like lvalues. */
4347 if (TREE_CODE (targ) == SAVE_EXPR)
4348 targ = TREE_OPERAND (targ, 0);
4350 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4352 if (TREE_CODE (arg) == SAVE_EXPR)
4355 targ = build_cplus_new (TREE_TYPE (arg), arg);
4356 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4359 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4360 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4361 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4364 /* Don't let anything else be handled specially. */
4368 /* Mark EXP saying that we need to be able to take the
4369 address of it; it should not be allocated in a register.
4370 Value is true if successful.
4372 C++: we do not allow `current_class_ptr' to be addressable. */
4375 cxx_mark_addressable (tree exp)
4380 switch (TREE_CODE (x))
4387 x = TREE_OPERAND (x, 0);
4391 if (x == current_class_ptr)
4393 error ("cannot take the address of %<this%>, which is an rvalue expression");
4394 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4400 /* Caller should not be trying to mark initialized
4401 constant fields addressable. */
4402 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4403 || DECL_IN_AGGR_P (x) == 0
4405 || DECL_EXTERNAL (x));
4410 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4411 && !DECL_ARTIFICIAL (x))
4413 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4416 ("address of explicit register variable %qD requested", x);
4419 else if (extra_warnings)
4421 (0, "address requested for %qD, which is declared %<register%>", x);
4423 TREE_ADDRESSABLE (x) = 1;
4427 TREE_ADDRESSABLE (x) = 1;
4431 TREE_ADDRESSABLE (x) = 1;
4435 TREE_ADDRESSABLE (x) = 1;
4436 cxx_mark_addressable (TREE_OPERAND (x, 0));
4444 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4447 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4449 tree orig_ifexp = ifexp;
4450 tree orig_op1 = op1;
4451 tree orig_op2 = op2;
4454 if (processing_template_decl)
4456 /* The standard says that the expression is type-dependent if
4457 IFEXP is type-dependent, even though the eventual type of the
4458 expression doesn't dependent on IFEXP. */
4459 if (type_dependent_expression_p (ifexp)
4460 /* As a GNU extension, the middle operand may be omitted. */
4461 || (op1 && type_dependent_expression_p (op1))
4462 || type_dependent_expression_p (op2))
4463 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4464 ifexp = build_non_dependent_expr (ifexp);
4466 op1 = build_non_dependent_expr (op1);
4467 op2 = build_non_dependent_expr (op2);
4470 expr = build_conditional_expr (ifexp, op1, op2);
4471 if (processing_template_decl && expr != error_mark_node)
4472 return build_min_non_dep (COND_EXPR, expr,
4473 orig_ifexp, orig_op1, orig_op2);
4477 /* Given a list of expressions, return a compound expression
4478 that performs them all and returns the value of the last of them. */
4480 tree build_x_compound_expr_from_list (tree list, const char *msg)
4482 tree expr = TREE_VALUE (list);
4484 if (TREE_CHAIN (list))
4487 pedwarn ("%s expression list treated as compound expression", msg);
4489 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4490 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4496 /* Handle overloading of the ',' operator when needed. */
4499 build_x_compound_expr (tree op1, tree op2)
4502 tree orig_op1 = op1;
4503 tree orig_op2 = op2;
4505 if (processing_template_decl)
4507 if (type_dependent_expression_p (op1)
4508 || type_dependent_expression_p (op2))
4509 return build_min_nt (COMPOUND_EXPR, op1, op2);
4510 op1 = build_non_dependent_expr (op1);
4511 op2 = build_non_dependent_expr (op2);
4514 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4515 /*overloaded_p=*/NULL);
4517 result = build_compound_expr (op1, op2);
4519 if (processing_template_decl && result != error_mark_node)
4520 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4525 /* Build a compound expression. */
4528 build_compound_expr (tree lhs, tree rhs)
4530 lhs = convert_to_void (lhs, "left-hand operand of comma");
4532 if (lhs == error_mark_node || rhs == error_mark_node)
4533 return error_mark_node;
4535 if (TREE_CODE (rhs) == TARGET_EXPR)
4537 /* If the rhs is a TARGET_EXPR, then build the compound
4538 expression inside the target_expr's initializer. This
4539 helps the compiler to eliminate unnecessary temporaries. */
4540 tree init = TREE_OPERAND (rhs, 1);
4542 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4543 TREE_OPERAND (rhs, 1) = init;
4548 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4551 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
4552 casts away constness. DIAG_FN gives the function to call if we
4553 need to issue a diagnostic; if it is NULL, no diagnostic will be
4554 issued. DESCRIPTION explains what operation is taking place. */
4557 check_for_casting_away_constness (tree src_type, tree dest_type,
4558 void (*diag_fn)(const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2),
4559 const char *description)
4561 if (diag_fn && casts_away_constness (src_type, dest_type))
4562 diag_fn ("%s from type %qT to type %qT casts away constness",
4563 description, src_type, dest_type);
4566 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
4567 (another pointer-to-member type in the same hierarchy) and return
4568 the converted expression. If ALLOW_INVERSE_P is permitted, a
4569 pointer-to-derived may be converted to pointer-to-base; otherwise,
4570 only the other direction is permitted. If C_CAST_P is true, this
4571 conversion is taking place as part of a C-style cast. */
4574 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
4577 if (TYPE_PTRMEM_P (type))
4581 if (TREE_CODE (expr) == PTRMEM_CST)
4582 expr = cplus_expand_constant (expr);
4583 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
4584 TYPE_PTRMEM_CLASS_TYPE (type),
4587 if (!integer_zerop (delta))
4588 expr = cp_build_binary_op (PLUS_EXPR,
4589 build_nop (ptrdiff_type_node, expr),
4591 return build_nop (type, expr);
4594 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4595 allow_inverse_p, c_cast_p);
4598 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
4599 a version of EXPR that has TREE_OVERFLOW and/or TREE_CONSTANT_OVERFLOW
4600 set iff they are set in ORIG. Otherwise, return EXPR unchanged. */
4603 ignore_overflows (tree expr, tree orig)
4605 if (TREE_CODE (expr) == INTEGER_CST
4606 && CONSTANT_CLASS_P (orig)
4607 && TREE_CODE (orig) != STRING_CST
4608 && (TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig)
4609 || TREE_CONSTANT_OVERFLOW (expr)
4610 != TREE_CONSTANT_OVERFLOW (orig)))
4612 if (!TREE_OVERFLOW (orig) && !TREE_CONSTANT_OVERFLOW (orig))
4613 /* Ensure constant sharing. */
4614 expr = build_int_cst_wide (TREE_TYPE (expr),
4615 TREE_INT_CST_LOW (expr),
4616 TREE_INT_CST_HIGH (expr));
4619 /* Avoid clobbering a shared constant. */
4620 expr = copy_node (expr);
4621 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
4622 TREE_CONSTANT_OVERFLOW (expr)
4623 = TREE_CONSTANT_OVERFLOW (orig);
4629 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
4630 this static_cast is being attempted as one of the possible casts
4631 allowed by a C-style cast. (In that case, accessibility of base
4632 classes is not considered, and it is OK to cast away
4633 constness.) Return the result of the cast. *VALID_P is set to
4634 indicate whether or not the cast was valid. */
4637 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
4643 void (*diag_fn)(const char*, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
4646 /* Assume the cast is valid. */
4649 intype = TREE_TYPE (expr);
4651 /* Determine what to do when casting away constness. */
4654 /* C-style casts are allowed to cast away constness. With
4655 WARN_CAST_QUAL, we still want to issue a warning. */
4656 diag_fn = warn_cast_qual ? warning0 : NULL;
4661 /* A static_cast may not cast away constness. */
4663 desc = "static_cast";
4666 /* [expr.static.cast]
4668 An lvalue of type "cv1 B", where B is a class type, can be cast
4669 to type "reference to cv2 D", where D is a class derived (clause
4670 _class.derived_) from B, if a valid standard conversion from
4671 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4672 same cv-qualification as, or greater cv-qualification than, cv1,
4673 and B is not a virtual base class of D. */
4674 /* We check this case before checking the validity of "TYPE t =
4675 EXPR;" below because for this case:
4678 struct D : public B { D(const B&); };
4680 void f() { static_cast<const D&>(b); }
4682 we want to avoid constructing a new D. The standard is not
4683 completely clear about this issue, but our interpretation is
4684 consistent with other compilers. */
4685 if (TREE_CODE (type) == REFERENCE_TYPE
4686 && CLASS_TYPE_P (TREE_TYPE (type))
4687 && CLASS_TYPE_P (intype)
4688 && real_lvalue_p (expr)
4689 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4690 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4691 build_pointer_type (TYPE_MAIN_VARIANT
4692 (TREE_TYPE (type))))
4694 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
4698 /* There is a standard conversion from "D*" to "B*" even if "B"
4699 is ambiguous or inaccessible. If this is really a
4700 static_cast, then we check both for inaccessibility and
4701 ambiguity. However, if this is a static_cast being performed
4702 because the user wrote a C-style cast, then accessibility is
4704 base = lookup_base (TREE_TYPE (type), intype,
4705 c_cast_p ? ba_unique : ba_check,
4708 /* Convert from "B*" to "D*". This function will check that "B"
4709 is not a virtual base of "D". */
4710 expr = build_base_path (MINUS_EXPR, build_address (expr),
4711 base, /*nonnull=*/false);
4712 /* Convert the pointer to a reference -- but then remember that
4713 there are no expressions with reference type in C++. */
4714 return convert_from_reference (build_nop (type, expr));
4719 /* [expr.static.cast]
4721 An expression e can be explicitly converted to a type T using a
4722 static_cast of the form static_cast<T>(e) if the declaration T
4723 t(e);" is well-formed, for some invented temporary variable
4725 result = perform_direct_initialization_if_possible (type, expr,
4729 result = convert_from_reference (result);
4731 /* Ignore any integer overflow caused by the cast. */
4732 result = ignore_overflows (result, orig);
4734 /* [expr.static.cast]
4736 If T is a reference type, the result is an lvalue; otherwise,
4737 the result is an rvalue. */
4738 if (TREE_CODE (type) != REFERENCE_TYPE)
4739 result = rvalue (result);
4743 /* [expr.static.cast]
4745 Any expression can be explicitly converted to type cv void. */
4746 if (TREE_CODE (type) == VOID_TYPE)
4747 return convert_to_void (expr, /*implicit=*/NULL);
4749 /* [expr.static.cast]
4751 The inverse of any standard conversion sequence (clause _conv_),
4752 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4753 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4754 (_conv.bool_) conversions, can be performed explicitly using
4755 static_cast subject to the restriction that the explicit
4756 conversion does not cast away constness (_expr.const.cast_), and
4757 the following additional rules for specific cases: */
4758 /* For reference, the conversions not excluded are: integral
4759 promotions, floating point promotion, integral conversions,
4760 floating point conversions, floating-integral conversions,
4761 pointer conversions, and pointer to member conversions. */
4764 A value of integral _or enumeration_ type can be explicitly
4765 converted to an enumeration type. */
4766 /* The effect of all that is that any conversion between any two
4767 types which are integral, floating, or enumeration types can be
4769 if ((INTEGRAL_TYPE_P (type) || SCALAR_FLOAT_TYPE_P (type))
4770 && (INTEGRAL_TYPE_P (intype) || SCALAR_FLOAT_TYPE_P (intype)))
4772 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
4774 /* Ignore any integer overflow caused by the cast. */
4775 expr = ignore_overflows (expr, orig);
4779 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4780 && CLASS_TYPE_P (TREE_TYPE (type))
4781 && CLASS_TYPE_P (TREE_TYPE (intype))
4782 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4783 (TREE_TYPE (intype))),
4784 build_pointer_type (TYPE_MAIN_VARIANT
4785 (TREE_TYPE (type)))))
4790 check_for_casting_away_constness (intype, type, diag_fn, desc);
4791 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
4792 c_cast_p ? ba_unique : ba_check,
4794 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4797 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4798 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4805 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4806 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4808 if (TYPE_PTRMEM_P (type))
4810 t1 = (build_ptrmem_type
4812 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4813 t2 = (build_ptrmem_type
4815 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4822 if (can_convert (t1, t2))
4825 check_for_casting_away_constness (intype, type, diag_fn,
4827 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
4832 /* [expr.static.cast]
4834 An rvalue of type "pointer to cv void" can be explicitly
4835 converted to a pointer to object type. A value of type pointer
4836 to object converted to "pointer to cv void" and back to the
4837 original pointer type will have its original value. */
4838 if (TREE_CODE (intype) == POINTER_TYPE
4839 && VOID_TYPE_P (TREE_TYPE (intype))
4840 && TYPE_PTROB_P (type))
4843 check_for_casting_away_constness (intype, type, diag_fn, desc);
4844 return build_nop (type, expr);
4848 return error_mark_node;
4851 /* Return an expression representing static_cast<TYPE>(EXPR). */
4854 build_static_cast (tree type, tree expr)
4859 if (type == error_mark_node || expr == error_mark_node)
4860 return error_mark_node;
4862 if (processing_template_decl)
4864 expr = build_min (STATIC_CAST_EXPR, type, expr);
4865 /* We don't know if it will or will not have side effects. */
4866 TREE_SIDE_EFFECTS (expr) = 1;
4867 return convert_from_reference (expr);
4870 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4871 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4872 if (TREE_CODE (type) != REFERENCE_TYPE
4873 && TREE_CODE (expr) == NOP_EXPR
4874 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4875 expr = TREE_OPERAND (expr, 0);
4877 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p);
4881 error ("invalid static_cast from type %qT to type %qT",
4882 TREE_TYPE (expr), type);
4883 return error_mark_node;
4886 /* EXPR is an expression with member function or pointer-to-member
4887 function type. TYPE is a pointer type. Converting EXPR to TYPE is
4888 not permitted by ISO C++, but we accept it in some modes. If we
4889 are not in one of those modes, issue a diagnostic. Return the
4890 converted expression. */
4893 convert_member_func_to_ptr (tree type, tree expr)
4898 intype = TREE_TYPE (expr);
4899 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
4900 || TREE_CODE (intype) == METHOD_TYPE);
4902 if (pedantic || warn_pmf2ptr)
4903 pedwarn ("converting from %qT to %qT", intype, type);
4905 if (TREE_CODE (intype) == METHOD_TYPE)
4906 expr = build_addr_func (expr);
4907 else if (TREE_CODE (expr) == PTRMEM_CST)
4908 expr = build_address (PTRMEM_CST_MEMBER (expr));
4911 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
4912 decl = build_address (decl);
4913 expr = get_member_function_from_ptrfunc (&decl, expr);
4916 return build_nop (type, expr);
4919 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
4920 If C_CAST_P is true, this reinterpret cast is being done as part of
4921 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
4922 indicate whether or not reinterpret_cast was valid. */
4925 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
4930 /* Assume the cast is invalid. */
4934 if (type == error_mark_node || error_operand_p (expr))
4935 return error_mark_node;
4937 intype = TREE_TYPE (expr);
4939 /* [expr.reinterpret.cast]
4940 An lvalue expression of type T1 can be cast to the type
4941 "reference to T2" if an expression of type "pointer to T1" can be
4942 explicitly converted to the type "pointer to T2" using a
4943 reinterpret_cast. */
4944 if (TREE_CODE (type) == REFERENCE_TYPE)
4946 if (! real_lvalue_p (expr))
4948 error ("invalid cast of an rvalue expression of type "
4951 return error_mark_node;
4954 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
4955 "B" are related class types; the reinterpret_cast does not
4956 adjust the pointer. */
4957 if (TYPE_PTR_P (intype)
4958 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
4959 COMPARE_BASE | COMPARE_DERIVED)))
4960 warning (0, "casting %qT to %qT does not dereference pointer",
4963 expr = build_unary_op (ADDR_EXPR, expr, 0);
4964 if (expr != error_mark_node)
4965 expr = build_reinterpret_cast_1
4966 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
4968 if (expr != error_mark_node)
4969 expr = build_indirect_ref (expr, 0);
4973 /* As a G++ extension, we consider conversions from member
4974 functions, and pointers to member functions to
4975 pointer-to-function and pointer-to-void types. If
4976 -Wno-pmf-conversions has not been specified,
4977 convert_member_func_to_ptr will issue an error message. */
4978 if ((TYPE_PTRMEMFUNC_P (intype)
4979 || TREE_CODE (intype) == METHOD_TYPE)
4980 && TYPE_PTR_P (type)
4981 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
4982 || VOID_TYPE_P (TREE_TYPE (type))))
4983 return convert_member_func_to_ptr (type, expr);
4985 /* If the cast is not to a reference type, the lvalue-to-rvalue,
4986 array-to-pointer, and function-to-pointer conversions are
4988 expr = decay_conversion (expr);
4990 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4991 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4992 if (TREE_CODE (expr) == NOP_EXPR
4993 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4994 expr = TREE_OPERAND (expr, 0);
4996 if (error_operand_p (expr))
4997 return error_mark_node;
4999 intype = TREE_TYPE (expr);
5001 /* [expr.reinterpret.cast]
5002 A pointer can be converted to any integral type large enough to
5004 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5006 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5007 pedwarn ("cast from %qT to %qT loses precision",
5010 /* [expr.reinterpret.cast]
5011 A value of integral or enumeration type can be explicitly
5012 converted to a pointer. */
5013 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5016 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5017 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5018 return fold_if_not_in_template (build_nop (type, expr));
5019 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5020 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5023 check_for_casting_away_constness (intype, type, error,
5024 "reinterpret_cast");
5025 /* Warn about possible alignment problems. */
5026 if (STRICT_ALIGNMENT && warn_cast_align
5027 && !VOID_TYPE_P (type)
5028 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5029 && COMPLETE_TYPE_P (TREE_TYPE (type))
5030 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5031 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5032 warning (0, "cast from %qT to %qT increases required alignment of "
5036 return fold_if_not_in_template (build_nop (type, expr));
5038 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5039 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5042 /* Only issue a warning, as we have always supported this
5043 where possible, and it is necessary in some cases. DR 195
5044 addresses this issue, but as of 2004/10/26 is still in
5046 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5047 return fold_if_not_in_template (build_nop (type, expr));
5049 else if (TREE_CODE (type) == VECTOR_TYPE)
5050 return fold_if_not_in_template (convert_to_vector (type, expr));
5051 else if (TREE_CODE (intype) == VECTOR_TYPE)
5052 return fold_if_not_in_template (convert_to_integer (type, expr));
5057 error ("invalid cast from type %qT to type %qT", intype, type);
5058 return error_mark_node;
5061 return cp_convert (type, expr);
5065 build_reinterpret_cast (tree type, tree expr)
5067 if (type == error_mark_node || expr == error_mark_node)
5068 return error_mark_node;
5070 if (processing_template_decl)
5072 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5074 if (!TREE_SIDE_EFFECTS (t)
5075 && type_dependent_expression_p (expr))
5076 /* There might turn out to be side effects inside expr. */
5077 TREE_SIDE_EFFECTS (t) = 1;
5078 return convert_from_reference (t);
5081 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5085 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5086 return an appropriate expression. Otherwise, return
5087 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5088 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5089 performing a C-style cast, its value upon return will indicate
5090 whether or not the conversion succeeded. */
5093 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5097 tree reference_type;
5099 /* Callers are responsible for handling error_mark_node as a
5100 destination type. */
5101 gcc_assert (dst_type != error_mark_node);
5102 /* In a template, callers should be building syntactic
5103 representations of casts, not using this machinery. */
5104 gcc_assert (!processing_template_decl);
5106 /* Assume the conversion is invalid. */
5110 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5113 error ("invalid use of const_cast with type %qT, "
5114 "which is not a pointer, "
5115 "reference, nor a pointer-to-data-member type", dst_type);
5116 return error_mark_node;
5119 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5122 error ("invalid use of const_cast with type %qT, which is a pointer "
5123 "or reference to a function type", dst_type);
5124 return error_mark_node;
5127 src_type = TREE_TYPE (expr);
5128 /* Expressions do not really have reference types. */
5129 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5130 src_type = TREE_TYPE (src_type);
5132 /* [expr.const.cast]
5134 An lvalue of type T1 can be explicitly converted to an lvalue of
5135 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5136 types) if a pointer to T1 can be explicitly converted to the type
5137 pointer to T2 using a const_cast. */
5138 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5140 reference_type = dst_type;
5141 if (! real_lvalue_p (expr))
5144 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5145 src_type, dst_type);
5146 return error_mark_node;
5148 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5149 src_type = build_pointer_type (src_type);
5153 reference_type = NULL_TREE;
5154 /* If the destination type is not a reference type, the
5155 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5156 conversions are performed. */
5157 src_type = type_decays_to (src_type);
5158 if (src_type == error_mark_node)
5159 return error_mark_node;
5162 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5163 && comp_ptr_ttypes_const (dst_type, src_type))
5168 /* This cast is actually a C-style cast. Issue a warning if
5169 the user is making a potentially unsafe cast. */
5171 check_for_casting_away_constness (src_type, dst_type,
5177 expr = build_unary_op (ADDR_EXPR, expr, 0);
5178 expr = build_nop (reference_type, expr);
5179 return convert_from_reference (expr);
5183 expr = decay_conversion (expr);
5184 /* build_c_cast puts on a NOP_EXPR to make the result not an
5185 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5186 non-lvalue context. */
5187 if (TREE_CODE (expr) == NOP_EXPR
5188 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5189 expr = TREE_OPERAND (expr, 0);
5190 return build_nop (dst_type, expr);
5195 error ("invalid const_cast from type %qT to type %qT",
5196 src_type, dst_type);
5197 return error_mark_node;
5201 build_const_cast (tree type, tree expr)
5203 if (type == error_mark_node || error_operand_p (expr))
5204 return error_mark_node;
5206 if (processing_template_decl)
5208 tree t = build_min (CONST_CAST_EXPR, type, expr);
5210 if (!TREE_SIDE_EFFECTS (t)
5211 && type_dependent_expression_p (expr))
5212 /* There might turn out to be side effects inside expr. */
5213 TREE_SIDE_EFFECTS (t) = 1;
5214 return convert_from_reference (t);
5217 return build_const_cast_1 (type, expr, /*complain=*/true,
5221 /* Build an expression representing an explicit C-style cast to type
5222 TYPE of expression EXPR. */
5225 build_c_cast (tree type, tree expr)
5231 if (type == error_mark_node || error_operand_p (expr))
5232 return error_mark_node;
5234 if (processing_template_decl)
5236 tree t = build_min (CAST_EXPR, type,
5237 tree_cons (NULL_TREE, value, NULL_TREE));
5238 /* We don't know if it will or will not have side effects. */
5239 TREE_SIDE_EFFECTS (t) = 1;
5240 return convert_from_reference (t);
5243 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5244 'Class') should always be retained, because this information aids
5245 in method lookup. */
5246 if (objc_is_object_ptr (type)
5247 && objc_is_object_ptr (TREE_TYPE (expr)))
5248 return build_nop (type, expr);
5250 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5251 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5252 if (TREE_CODE (type) != REFERENCE_TYPE
5253 && TREE_CODE (value) == NOP_EXPR
5254 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5255 value = TREE_OPERAND (value, 0);
5257 if (TREE_CODE (type) == ARRAY_TYPE)
5259 /* Allow casting from T1* to T2[] because Cfront allows it.
5260 NIHCL uses it. It is not valid ISO C++ however. */
5261 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5263 pedwarn ("ISO C++ forbids casting to an array type %qT", type);
5264 type = build_pointer_type (TREE_TYPE (type));
5268 error ("ISO C++ forbids casting to an array type %qT", type);
5269 return error_mark_node;
5273 if (TREE_CODE (type) == FUNCTION_TYPE
5274 || TREE_CODE (type) == METHOD_TYPE)
5276 error ("invalid cast to function type %qT", type);
5277 return error_mark_node;
5280 /* A C-style cast can be a const_cast. */
5281 result = build_const_cast_1 (type, value, /*complain=*/false,
5286 /* Or a static cast. */
5287 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5289 /* Or a reinterpret_cast. */
5291 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5293 /* The static_cast or reinterpret_cast may be followed by a
5296 /* A valid cast may result in errors if, for example, a
5297 conversion to am ambiguous base class is required. */
5298 && !error_operand_p (result))
5302 /* Non-class rvalues always have cv-unqualified type. */
5303 if (!CLASS_TYPE_P (type))
5304 type = TYPE_MAIN_VARIANT (type);
5305 result_type = TREE_TYPE (result);
5306 if (!CLASS_TYPE_P (result_type))
5307 result_type = TYPE_MAIN_VARIANT (result_type);
5308 /* If the type of RESULT does not match TYPE, perform a
5309 const_cast to make it match. If the static_cast or
5310 reinterpret_cast succeeded, we will differ by at most
5311 cv-qualification, so the follow-on const_cast is guaranteed
5313 if (!same_type_p (non_reference (type), non_reference (result_type)))
5315 result = build_const_cast_1 (type, result, false, &valid_p);
5316 gcc_assert (valid_p);
5321 return error_mark_node;
5324 /* Build an assignment expression of lvalue LHS from value RHS.
5325 MODIFYCODE is the code for a binary operator that we use
5326 to combine the old value of LHS with RHS to get the new value.
5327 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5329 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5332 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5336 tree lhstype = TREE_TYPE (lhs);
5337 tree olhstype = lhstype;
5338 tree olhs = NULL_TREE;
5339 bool plain_assign = (modifycode == NOP_EXPR);
5341 /* Avoid duplicate error messages from operands that had errors. */
5342 if (lhs == error_mark_node || rhs == error_mark_node)
5343 return error_mark_node;
5345 /* Handle control structure constructs used as "lvalues". */
5346 switch (TREE_CODE (lhs))
5348 /* Handle --foo = 5; as these are valid constructs in C++. */
5349 case PREDECREMENT_EXPR:
5350 case PREINCREMENT_EXPR:
5351 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5352 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5353 stabilize_reference (TREE_OPERAND (lhs, 0)),
5354 TREE_OPERAND (lhs, 1));
5355 return build2 (COMPOUND_EXPR, lhstype,
5357 build_modify_expr (TREE_OPERAND (lhs, 0),
5360 /* Handle (a, b) used as an "lvalue". */
5362 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
5364 if (newrhs == error_mark_node)
5365 return error_mark_node;
5366 return build2 (COMPOUND_EXPR, lhstype,
5367 TREE_OPERAND (lhs, 0), newrhs);
5370 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5371 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5372 stabilize_reference (TREE_OPERAND (lhs, 0)),
5373 TREE_OPERAND (lhs, 1));
5374 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
5375 if (newrhs == error_mark_node)
5376 return error_mark_node;
5377 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5381 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
5382 when neither operand has side-effects. */
5383 if (!lvalue_or_else (lhs, lv_assign))
5384 return error_mark_node;
5386 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
5387 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
5389 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
5390 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
5392 TREE_OPERAND (lhs, 0),
5393 TREE_OPERAND (lhs, 1)),
5394 TREE_OPERAND (lhs, 0),
5395 TREE_OPERAND (lhs, 1));
5398 /* Handle (a ? b : c) used as an "lvalue". */
5401 /* Produce (a ? (b = rhs) : (c = rhs))
5402 except that the RHS goes through a save-expr
5403 so the code to compute it is only emitted once. */
5405 tree preeval = NULL_TREE;
5407 rhs = stabilize_expr (rhs, &preeval);
5409 /* Check this here to avoid odd errors when trying to convert
5410 a throw to the type of the COND_EXPR. */
5411 if (!lvalue_or_else (lhs, lv_assign))
5412 return error_mark_node;
5414 cond = build_conditional_expr
5415 (TREE_OPERAND (lhs, 0),
5416 build_modify_expr (cp_convert (TREE_TYPE (lhs),
5417 TREE_OPERAND (lhs, 1)),
5419 build_modify_expr (cp_convert (TREE_TYPE (lhs),
5420 TREE_OPERAND (lhs, 2)),
5423 if (cond == error_mark_node)
5425 /* Make sure the code to compute the rhs comes out
5426 before the split. */
5428 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5436 if (modifycode == INIT_EXPR)
5438 if (TREE_CODE (rhs) == CONSTRUCTOR)
5440 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5441 /* Call convert to generate an error; see PR 11063. */
5442 rhs = convert (lhstype, rhs);
5443 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
5444 TREE_SIDE_EFFECTS (result) = 1;
5447 else if (! IS_AGGR_TYPE (lhstype))
5448 /* Do the default thing. */;
5451 result = build_special_member_call (lhs, complete_ctor_identifier,
5452 build_tree_list (NULL_TREE, rhs),
5453 lhstype, LOOKUP_NORMAL);
5454 if (result == NULL_TREE)
5455 return error_mark_node;
5461 lhs = require_complete_type (lhs);
5462 if (lhs == error_mark_node)
5463 return error_mark_node;
5465 if (modifycode == NOP_EXPR)
5467 /* `operator=' is not an inheritable operator. */
5468 if (! IS_AGGR_TYPE (lhstype))
5469 /* Do the default thing. */;
5472 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5473 lhs, rhs, make_node (NOP_EXPR),
5474 /*overloaded_p=*/NULL);
5475 if (result == NULL_TREE)
5476 return error_mark_node;
5483 /* A binary op has been requested. Combine the old LHS
5484 value with the RHS producing the value we should actually
5485 store into the LHS. */
5487 gcc_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE));
5488 lhs = stabilize_reference (lhs);
5489 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
5490 if (newrhs == error_mark_node)
5492 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
5493 TREE_TYPE (lhs), TREE_TYPE (rhs));
5494 return error_mark_node;
5497 /* Now it looks like a plain assignment. */
5498 modifycode = NOP_EXPR;
5500 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
5501 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
5504 /* The left-hand side must be an lvalue. */
5505 if (!lvalue_or_else (lhs, lv_assign))
5506 return error_mark_node;
5508 /* Warn about modifying something that is `const'. Don't warn if
5509 this is initialization. */
5510 if (modifycode != INIT_EXPR
5511 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5512 /* Functions are not modifiable, even though they are
5514 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5515 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5516 /* If it's an aggregate and any field is const, then it is
5517 effectively const. */
5518 || (CLASS_TYPE_P (lhstype)
5519 && C_TYPE_FIELDS_READONLY (lhstype))))
5520 readonly_error (lhs, "assignment", 0);
5522 /* If storing into a structure or union member, it has probably been
5523 given type `int'. Compute the type that would go with the actual
5524 amount of storage the member occupies. */
5526 if (TREE_CODE (lhs) == COMPONENT_REF
5527 && (TREE_CODE (lhstype) == INTEGER_TYPE
5528 || TREE_CODE (lhstype) == REAL_TYPE
5529 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5531 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5533 /* If storing in a field that is in actuality a short or narrower
5534 than one, we must store in the field in its actual type. */
5536 if (lhstype != TREE_TYPE (lhs))
5538 /* Avoid warnings converting integral types back into enums for
5540 if (TREE_CODE (lhstype) == INTEGER_TYPE
5541 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5543 if (TREE_SIDE_EFFECTS (lhs))
5544 lhs = stabilize_reference (lhs);
5547 lhs = copy_node (lhs);
5548 TREE_TYPE (lhs) = lhstype;
5552 /* Convert new value to destination type. */
5554 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5558 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5559 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5561 error ("incompatible types in assignment of %qT to %qT",
5562 TREE_TYPE (rhs), lhstype);
5563 return error_mark_node;
5566 /* Allow array assignment in compiler-generated code. */
5567 if (! DECL_ARTIFICIAL (current_function_decl))
5568 pedwarn ("ISO C++ forbids assignment of arrays");
5570 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5571 ? 1 + (modifycode != INIT_EXPR): 0;
5572 return build_vec_init (lhs, NULL_TREE, newrhs,
5573 /*explicit_default_init_p=*/false,
5577 if (modifycode == INIT_EXPR)
5578 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5579 "initialization", NULL_TREE, 0);
5582 /* Avoid warnings on enum bit fields. */
5583 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5584 && TREE_CODE (lhstype) == INTEGER_TYPE)
5586 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5588 newrhs = convert_force (lhstype, newrhs, 0);
5591 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5593 if (TREE_CODE (newrhs) == CALL_EXPR
5594 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5595 newrhs = build_cplus_new (lhstype, newrhs);
5597 /* Can't initialize directly from a TARGET_EXPR, since that would
5598 cause the lhs to be constructed twice, and possibly result in
5599 accidental self-initialization. So we force the TARGET_EXPR to be
5600 expanded without a target. */
5601 if (TREE_CODE (newrhs) == TARGET_EXPR)
5602 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5603 TREE_OPERAND (newrhs, 0));
5606 if (newrhs == error_mark_node)
5607 return error_mark_node;
5609 if (c_dialect_objc () && flag_objc_gc)
5611 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
5617 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5618 lhstype, lhs, newrhs);
5620 TREE_SIDE_EFFECTS (result) = 1;
5622 TREE_NO_WARNING (result) = 1;
5624 /* If we got the LHS in a different type for storing in,
5625 convert the result back to the nominal type of LHS
5626 so that the value we return always has the same type
5627 as the LHS argument. */
5629 if (olhstype == TREE_TYPE (result))
5633 result = build2 (COMPOUND_EXPR, olhstype, result, olhs);
5634 TREE_NO_WARNING (result) = 1;
5637 return convert_for_assignment (olhstype, result, "assignment",
5642 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5644 if (processing_template_decl)
5645 return build_min_nt (MODOP_EXPR, lhs,
5646 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5648 if (modifycode != NOP_EXPR)
5650 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5651 make_node (modifycode),
5652 /*overloaded_p=*/NULL);
5655 TREE_NO_WARNING (rval) = 1;
5659 return build_modify_expr (lhs, modifycode, rhs);
5663 /* Get difference in deltas for different pointer to member function
5664 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5665 the conversion is invalid, the constant is zero. If
5666 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
5667 If C_CAST_P is true this conversion is taking place as part of a
5670 Note that the naming of FROM and TO is kind of backwards; the return
5671 value is what we add to a TO in order to get a FROM. They are named
5672 this way because we call this function to find out how to convert from
5673 a pointer to member of FROM to a pointer to member of TO. */
5676 get_delta_difference (tree from, tree to,
5677 bool allow_inverse_p,
5684 /* Assume no conversion is required. */
5685 result = integer_zero_node;
5686 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
5687 if (kind == bk_inaccessible || kind == bk_ambig)
5688 error (" in pointer to member function conversion");
5691 if (kind != bk_via_virtual)
5692 result = BINFO_OFFSET (binfo);
5695 tree virt_binfo = binfo_from_vbase (binfo);
5697 /* This is a reinterpret cast, we choose to do nothing. */
5698 if (allow_inverse_p)
5699 warning (0, "pointer to member cast via virtual base %qT",
5700 BINFO_TYPE (virt_binfo));
5702 error ("pointer to member conversion via virtual base %qT",
5703 BINFO_TYPE (virt_binfo));
5706 else if (same_type_ignoring_top_level_qualifiers_p (from, to))
5707 /* Pointer to member of incomplete class is permitted*/;
5708 else if (!allow_inverse_p)
5710 error_not_base_type (from, to);
5711 error (" in pointer to member conversion");
5715 binfo = lookup_base (from, to, c_cast_p ? ba_unique : ba_check, &kind);
5718 if (kind != bk_via_virtual)
5719 result = size_diffop (size_zero_node, BINFO_OFFSET (binfo));
5722 /* This is a reinterpret cast, we choose to do nothing. */
5723 tree virt_binfo = binfo_from_vbase (binfo);
5725 warning (0, "pointer to member cast via virtual base %qT",
5726 BINFO_TYPE (virt_binfo));
5731 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
5735 /* Return a constructor for the pointer-to-member-function TYPE using
5736 the other components as specified. */
5739 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5744 VEC(constructor_elt, gc) *v;
5746 /* Pull the FIELD_DECLs out of the type. */
5747 pfn_field = TYPE_FIELDS (type);
5748 delta_field = TREE_CHAIN (pfn_field);
5750 /* Make sure DELTA has the type we want. */
5751 delta = convert_and_check (delta_type_node, delta);
5753 /* Finish creating the initializer. */
5754 v = VEC_alloc(constructor_elt, gc, 2);
5755 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
5756 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
5757 u = build_constructor (type, v);
5758 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
5759 TREE_INVARIANT (u) = TREE_INVARIANT (pfn) & TREE_INVARIANT (delta);
5760 TREE_STATIC (u) = (TREE_CONSTANT (u)
5761 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5763 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5768 /* Build a constructor for a pointer to member function. It can be
5769 used to initialize global variables, local variable, or used
5770 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5773 If FORCE is nonzero, then force this conversion, even if
5774 we would rather not do it. Usually set when using an explicit
5775 cast. A C-style cast is being processed iff C_CAST_P is true.
5777 Return error_mark_node, if something goes wrong. */
5780 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
5786 if (error_operand_p (pfn))
5787 return error_mark_node;
5789 pfn_type = TREE_TYPE (pfn);
5790 to_type = build_ptrmemfunc_type (type);
5792 /* Handle multiple conversions of pointer to member functions. */
5793 if (TYPE_PTRMEMFUNC_P (pfn_type))
5795 tree delta = NULL_TREE;
5796 tree npfn = NULL_TREE;
5800 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
5801 error ("invalid conversion to type %qT from type %qT",
5804 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5805 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5809 /* We don't have to do any conversion to convert a
5810 pointer-to-member to its own type. But, we don't want to
5811 just return a PTRMEM_CST if there's an explicit cast; that
5812 cast should make the expression an invalid template argument. */
5813 if (TREE_CODE (pfn) != PTRMEM_CST)
5815 if (same_type_p (to_type, pfn_type))
5817 else if (integer_zerop (n))
5818 return build_reinterpret_cast (to_type, pfn);
5821 if (TREE_SIDE_EFFECTS (pfn))
5822 pfn = save_expr (pfn);
5824 /* Obtain the function pointer and the current DELTA. */
5825 if (TREE_CODE (pfn) == PTRMEM_CST)
5826 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
5829 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
5830 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
5833 /* Just adjust the DELTA field. */
5834 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5835 (TREE_TYPE (delta), ptrdiff_type_node));
5836 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
5837 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
5838 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
5839 return build_ptrmemfunc1 (to_type, delta, npfn);
5842 /* Handle null pointer to member function conversions. */
5843 if (integer_zerop (pfn))
5845 pfn = build_c_cast (type, integer_zero_node);
5846 return build_ptrmemfunc1 (to_type,
5851 if (type_unknown_p (pfn))
5852 return instantiate_type (type, pfn, tf_error | tf_warning);
5854 fn = TREE_OPERAND (pfn, 0);
5855 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
5856 /* In a template, we will have preserved the
5858 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
5859 return make_ptrmem_cst (to_type, fn);
5862 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
5865 ??? There is no consistency as to the types returned for the above
5866 values. Some code acts as if it were a sizetype and some as if it were
5867 integer_type_node. */
5870 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
5872 tree type = TREE_TYPE (cst);
5873 tree fn = PTRMEM_CST_MEMBER (cst);
5874 tree ptr_class, fn_class;
5876 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
5878 /* The class that the function belongs to. */
5879 fn_class = DECL_CONTEXT (fn);
5881 /* The class that we're creating a pointer to member of. */
5882 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
5884 /* First, calculate the adjustment to the function's class. */
5885 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
5888 if (!DECL_VIRTUAL_P (fn))
5889 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
5892 /* If we're dealing with a virtual function, we have to adjust 'this'
5893 again, to point to the base which provides the vtable entry for
5894 fn; the call will do the opposite adjustment. */
5895 tree orig_class = DECL_CONTEXT (fn);
5896 tree binfo = binfo_or_else (orig_class, fn_class);
5897 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
5898 *delta, BINFO_OFFSET (binfo));
5899 *delta = fold_if_not_in_template (*delta);
5901 /* We set PFN to the vtable offset at which the function can be
5902 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
5903 case delta is shifted left, and then incremented). */
5904 *pfn = DECL_VINDEX (fn);
5905 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
5906 TYPE_SIZE_UNIT (vtable_entry_type));
5907 *pfn = fold_if_not_in_template (*pfn);
5909 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
5911 case ptrmemfunc_vbit_in_pfn:
5912 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
5914 *pfn = fold_if_not_in_template (*pfn);
5917 case ptrmemfunc_vbit_in_delta:
5918 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
5919 *delta, integer_one_node);
5920 *delta = fold_if_not_in_template (*delta);
5921 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
5922 *delta, integer_one_node);
5923 *delta = fold_if_not_in_template (*delta);
5930 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
5931 *pfn = fold_if_not_in_template (*pfn);
5935 /* Return an expression for PFN from the pointer-to-member function
5939 pfn_from_ptrmemfunc (tree t)
5941 if (TREE_CODE (t) == PTRMEM_CST)
5946 expand_ptrmemfunc_cst (t, &delta, &pfn);
5951 return build_ptrmemfunc_access_expr (t, pfn_identifier);
5954 /* Convert value RHS to type TYPE as preparation for an assignment to
5955 an lvalue of type TYPE. ERRTYPE is a string to use in error
5956 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
5957 are doing the conversion in order to pass the PARMNUMth argument of
5961 convert_for_assignment (tree type, tree rhs,
5962 const char *errtype, tree fndecl, int parmnum)
5965 enum tree_code coder;
5967 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
5968 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
5969 rhs = TREE_OPERAND (rhs, 0);
5971 rhstype = TREE_TYPE (rhs);
5972 coder = TREE_CODE (rhstype);
5974 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
5975 && vector_types_convertible_p (type, rhstype))
5976 return convert (type, rhs);
5978 if (rhs == error_mark_node || rhstype == error_mark_node)
5979 return error_mark_node;
5980 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
5981 return error_mark_node;
5983 /* The RHS of an assignment cannot have void type. */
5984 if (coder == VOID_TYPE)
5986 error ("void value not ignored as it ought to be");
5987 return error_mark_node;
5990 /* Simplify the RHS if possible. */
5991 if (TREE_CODE (rhs) == CONST_DECL)
5992 rhs = DECL_INITIAL (rhs);
5994 if (c_dialect_objc ())
5997 tree rname = fndecl;
5999 if (!strcmp (errtype, "assignment"))
6001 else if (!strcmp (errtype, "initialization"))
6005 tree selector = objc_message_selector ();
6009 if (selector && parmno > 1)
6016 if (objc_compare_types (type, rhstype, parmno, rname))
6017 return convert (type, rhs);
6022 The expression is implicitly converted (clause _conv_) to the
6023 cv-unqualified type of the left operand.
6025 We allow bad conversions here because by the time we get to this point
6026 we are committed to doing the conversion. If we end up doing a bad
6027 conversion, convert_like will complain. */
6028 if (!can_convert_arg_bad (type, rhstype, rhs))
6030 /* When -Wno-pmf-conversions is use, we just silently allow
6031 conversions from pointers-to-members to plain pointers. If
6032 the conversion doesn't work, cp_convert will complain. */
6034 && TYPE_PTR_P (type)
6035 && TYPE_PTRMEMFUNC_P (rhstype))
6036 rhs = cp_convert (strip_top_quals (type), rhs);
6039 /* If the right-hand side has unknown type, then it is an
6040 overloaded function. Call instantiate_type to get error
6042 if (rhstype == unknown_type_node)
6043 instantiate_type (type, rhs, tf_error | tf_warning);
6045 error ("cannot convert %qT to %qT for argument %qP to %qD",
6046 rhstype, type, parmnum, fndecl);
6048 error ("cannot convert %qT to %qT in %s", rhstype, type, errtype);
6049 return error_mark_node;
6052 if (warn_missing_format_attribute)
6054 const enum tree_code codel = TREE_CODE (type);
6055 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6057 && check_missing_format_attribute (type, rhstype))
6058 warning (OPT_Wmissing_format_attribute,
6059 "%s might be a candidate for a format attribute",
6063 return perform_implicit_conversion (strip_top_quals (type), rhs);
6066 /* Convert RHS to be of type TYPE.
6067 If EXP is nonzero, it is the target of the initialization.
6068 ERRTYPE is a string to use in error messages.
6070 Two major differences between the behavior of
6071 `convert_for_assignment' and `convert_for_initialization'
6072 are that references are bashed in the former, while
6073 copied in the latter, and aggregates are assigned in
6074 the former (operator=) while initialized in the
6077 If using constructor make sure no conversion operator exists, if one does
6078 exist, an ambiguity exists.
6080 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6083 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6084 const char *errtype, tree fndecl, int parmnum)
6086 enum tree_code codel = TREE_CODE (type);
6088 enum tree_code coder;
6090 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6091 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6092 if (TREE_CODE (rhs) == NOP_EXPR
6093 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6094 && codel != REFERENCE_TYPE)
6095 rhs = TREE_OPERAND (rhs, 0);
6097 if (rhs == error_mark_node
6098 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6099 return error_mark_node;
6101 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6102 && TREE_CODE (type) != ARRAY_TYPE
6103 && (TREE_CODE (type) != REFERENCE_TYPE
6104 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6105 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6106 && (TREE_CODE (type) != REFERENCE_TYPE
6107 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6108 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6109 rhs = decay_conversion (rhs);
6111 rhstype = TREE_TYPE (rhs);
6112 coder = TREE_CODE (rhstype);
6114 if (coder == ERROR_MARK)
6115 return error_mark_node;
6117 /* We accept references to incomplete types, so we can
6118 return here before checking if RHS is of complete type. */
6120 if (codel == REFERENCE_TYPE)
6122 /* This should eventually happen in convert_arguments. */
6123 int savew = 0, savee = 0;
6126 savew = warningcount, savee = errorcount;
6127 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6131 if (warningcount > savew)
6132 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6133 else if (errorcount > savee)
6134 error ("in passing argument %P of %q+D", parmnum, fndecl);
6140 exp = require_complete_type (exp);
6141 if (exp == error_mark_node)
6142 return error_mark_node;
6144 rhstype = non_reference (rhstype);
6146 type = complete_type (type);
6148 if (IS_AGGR_TYPE (type))
6149 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6151 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
6154 /* If RETVAL is the address of, or a reference to, a local variable or
6155 temporary give an appropriate warning. */
6158 maybe_warn_about_returning_address_of_local (tree retval)
6160 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6161 tree whats_returned = retval;
6165 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6166 whats_returned = TREE_OPERAND (whats_returned, 1);
6167 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
6168 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
6169 || TREE_CODE (whats_returned) == NOP_EXPR)
6170 whats_returned = TREE_OPERAND (whats_returned, 0);
6175 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6177 whats_returned = TREE_OPERAND (whats_returned, 0);
6179 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6181 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6182 || TREE_CODE (whats_returned) == TARGET_EXPR)
6184 warning (0, "returning reference to temporary");
6187 if (TREE_CODE (whats_returned) == VAR_DECL
6188 && DECL_NAME (whats_returned)
6189 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6191 warning (0, "reference to non-lvalue returned");
6196 if (DECL_P (whats_returned)
6197 && DECL_NAME (whats_returned)
6198 && DECL_FUNCTION_SCOPE_P (whats_returned)
6199 && !(TREE_STATIC (whats_returned)
6200 || TREE_PUBLIC (whats_returned)))
6202 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6203 warning (0, "reference to local variable %q+D returned",
6206 warning (0, "address of local variable %q+D returned",
6212 /* Check that returning RETVAL from the current function is valid.
6213 Return an expression explicitly showing all conversions required to
6214 change RETVAL into the function return type, and to assign it to
6215 the DECL_RESULT for the function. Set *NO_WARNING to true if
6216 code reaches end of non-void function warning shouldn't be issued
6217 on this RETURN_EXPR. */
6220 check_return_expr (tree retval, bool *no_warning)
6223 /* The type actually returned by the function, after any
6226 int fn_returns_value_p;
6228 *no_warning = false;
6230 /* A `volatile' function is one that isn't supposed to return, ever.
6231 (This is a G++ extension, used to get better code for functions
6232 that call the `volatile' function.) */
6233 if (TREE_THIS_VOLATILE (current_function_decl))
6234 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6236 /* Check for various simple errors. */
6237 if (DECL_DESTRUCTOR_P (current_function_decl))
6240 error ("returning a value from a destructor");
6243 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6245 if (in_function_try_handler)
6246 /* If a return statement appears in a handler of the
6247 function-try-block of a constructor, the program is ill-formed. */
6248 error ("cannot return from a handler of a function-try-block of a constructor");
6250 /* You can't return a value from a constructor. */
6251 error ("returning a value from a constructor");
6255 if (processing_template_decl)
6257 current_function_returns_value = 1;
6261 /* When no explicit return-value is given in a function with a named
6262 return value, the named return value is used. */
6263 result = DECL_RESULT (current_function_decl);
6264 valtype = TREE_TYPE (result);
6265 gcc_assert (valtype != NULL_TREE);
6266 fn_returns_value_p = !VOID_TYPE_P (valtype);
6267 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6270 /* Check for a return statement with no return value in a function
6271 that's supposed to return a value. */
6272 if (!retval && fn_returns_value_p)
6274 pedwarn ("return-statement with no value, in function returning %qT",
6276 /* Clear this, so finish_function won't say that we reach the
6277 end of a non-void function (which we don't, we gave a
6279 current_function_returns_null = 0;
6280 /* And signal caller that TREE_NO_WARNING should be set on the
6281 RETURN_EXPR to avoid control reaches end of non-void function
6282 warnings in tree-cfg.c. */
6285 /* Check for a return statement with a value in a function that
6286 isn't supposed to return a value. */
6287 else if (retval && !fn_returns_value_p)
6289 if (VOID_TYPE_P (TREE_TYPE (retval)))
6290 /* You can return a `void' value from a function of `void'
6291 type. In that case, we have to evaluate the expression for
6292 its side-effects. */
6293 finish_expr_stmt (retval);
6295 pedwarn ("return-statement with a value, in function "
6296 "returning 'void'");
6298 current_function_returns_null = 1;
6300 /* There's really no value to return, after all. */
6304 /* Remember that this function can sometimes return without a
6306 current_function_returns_null = 1;
6308 /* Remember that this function did return a value. */
6309 current_function_returns_value = 1;
6311 /* Check for erroneous operands -- but after giving ourselves a
6312 chance to provide an error about returning a value from a void
6314 if (error_operand_p (retval))
6316 current_function_return_value = error_mark_node;
6317 return error_mark_node;
6320 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
6321 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
6322 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
6323 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
6325 && null_ptr_cst_p (retval))
6326 warning (0, "%<operator new%> must not return NULL unless it is "
6327 "declared %<throw()%> (or -fcheck-new is in effect)");
6329 /* Effective C++ rule 15. See also start_function. */
6331 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
6335 /* The function return type must be a reference to the current
6337 if (TREE_CODE (valtype) == REFERENCE_TYPE
6338 && same_type_ignoring_top_level_qualifiers_p
6339 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
6341 /* Returning '*this' is obviously OK. */
6342 if (retval == current_class_ref)
6344 /* If we are calling a function whose return type is the same of
6345 the current class reference, it is ok. */
6346 else if (TREE_CODE (retval) == INDIRECT_REF
6347 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
6352 warning (0, "%<operator=%> should return a reference to %<*this%>");
6355 /* The fabled Named Return Value optimization, as per [class.copy]/15:
6357 [...] For a function with a class return type, if the expression
6358 in the return statement is the name of a local object, and the cv-
6359 unqualified type of the local object is the same as the function
6360 return type, an implementation is permitted to omit creating the tem-
6361 porary object to hold the function return value [...]
6363 So, if this is a value-returning function that always returns the same
6364 local variable, remember it.
6366 It might be nice to be more flexible, and choose the first suitable
6367 variable even if the function sometimes returns something else, but
6368 then we run the risk of clobbering the variable we chose if the other
6369 returned expression uses the chosen variable somehow. And people expect
6370 this restriction, anyway. (jason 2000-11-19)
6372 See finish_function and finalize_nrv for the rest of this optimization. */
6374 if (fn_returns_value_p && flag_elide_constructors)
6376 if (retval != NULL_TREE
6377 && (current_function_return_value == NULL_TREE
6378 || current_function_return_value == retval)
6379 && TREE_CODE (retval) == VAR_DECL
6380 && DECL_CONTEXT (retval) == current_function_decl
6381 && ! TREE_STATIC (retval)
6382 && (DECL_ALIGN (retval)
6383 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6384 && same_type_p ((TYPE_MAIN_VARIANT
6385 (TREE_TYPE (retval))),
6387 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
6388 current_function_return_value = retval;
6390 current_function_return_value = error_mark_node;
6393 /* We don't need to do any conversions when there's nothing being
6398 /* Do any required conversions. */
6399 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6400 /* No conversions are required. */
6404 /* The type the function is declared to return. */
6405 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6407 /* The functype's return type will have been set to void, if it
6408 was an incomplete type. Just treat this as 'return;' */
6409 if (VOID_TYPE_P (functype))
6410 return error_mark_node;
6412 /* First convert the value to the function's return type, then
6413 to the type of return value's location to handle the
6414 case that functype is smaller than the valtype. */
6415 retval = convert_for_initialization
6416 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
6417 "return", NULL_TREE, 0);
6418 retval = convert (valtype, retval);
6420 /* If the conversion failed, treat this just like `return;'. */
6421 if (retval == error_mark_node)
6423 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6424 else if (! current_function_returns_struct
6425 && TREE_CODE (retval) == TARGET_EXPR
6426 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6427 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6428 TREE_OPERAND (retval, 0));
6430 maybe_warn_about_returning_address_of_local (retval);
6433 /* Actually copy the value returned into the appropriate location. */
6434 if (retval && retval != result)
6435 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
6441 /* Returns nonzero if the pointer-type FROM can be converted to the
6442 pointer-type TO via a qualification conversion. If CONSTP is -1,
6443 then we return nonzero if the pointers are similar, and the
6444 cv-qualification signature of FROM is a proper subset of that of TO.
6446 If CONSTP is positive, then all outer pointers have been
6450 comp_ptr_ttypes_real (tree to, tree from, int constp)
6452 bool to_more_cv_qualified = false;
6454 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6456 if (TREE_CODE (to) != TREE_CODE (from))
6459 if (TREE_CODE (from) == OFFSET_TYPE
6460 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
6461 TYPE_OFFSET_BASETYPE (to)))
6464 /* Const and volatile mean something different for function types,
6465 so the usual checks are not appropriate. */
6466 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6468 /* In Objective-C++, some types may have been 'volatilized' by
6469 the compiler for EH; when comparing them here, the volatile
6470 qualification must be ignored. */
6471 bool objc_quals_match = objc_type_quals_match (to, from);
6473 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
6476 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
6480 to_more_cv_qualified = true;
6484 constp &= TYPE_READONLY (to);
6487 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
6488 return ((constp >= 0 || to_more_cv_qualified)
6489 && same_type_ignoring_top_level_qualifiers_p (to, from));
6493 /* When comparing, say, char ** to char const **, this function takes
6494 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6495 types to this function. */
6498 comp_ptr_ttypes (tree to, tree from)
6500 return comp_ptr_ttypes_real (to, from, 1);
6503 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6504 type or inheritance-related types, regardless of cv-quals. */
6507 ptr_reasonably_similar (tree to, tree from)
6509 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6511 /* Any target type is similar enough to void. */
6512 if (TREE_CODE (to) == VOID_TYPE
6513 || TREE_CODE (from) == VOID_TYPE)
6516 if (TREE_CODE (to) != TREE_CODE (from))
6519 if (TREE_CODE (from) == OFFSET_TYPE
6520 && comptypes (TYPE_OFFSET_BASETYPE (to),
6521 TYPE_OFFSET_BASETYPE (from),
6522 COMPARE_BASE | COMPARE_DERIVED))
6525 if (TREE_CODE (to) == VECTOR_TYPE
6526 && vector_types_convertible_p (to, from))
6529 if (TREE_CODE (to) == INTEGER_TYPE
6530 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6533 if (TREE_CODE (to) == FUNCTION_TYPE)
6536 if (TREE_CODE (to) != POINTER_TYPE)
6538 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6539 COMPARE_BASE | COMPARE_DERIVED);
6543 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
6544 pointer-to-member types) are the same, ignoring cv-qualification at
6548 comp_ptr_ttypes_const (tree to, tree from)
6550 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6552 if (TREE_CODE (to) != TREE_CODE (from))
6555 if (TREE_CODE (from) == OFFSET_TYPE
6556 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6557 TYPE_OFFSET_BASETYPE (to)))
6560 if (TREE_CODE (to) != POINTER_TYPE)
6561 return same_type_ignoring_top_level_qualifiers_p (to, from);
6565 /* Returns the type qualifiers for this type, including the qualifiers on the
6566 elements for an array type. */
6569 cp_type_quals (tree type)
6571 type = strip_array_types (type);
6572 if (type == error_mark_node)
6573 return TYPE_UNQUALIFIED;
6574 return TYPE_QUALS (type);
6577 /* Returns nonzero if the TYPE contains a mutable member. */
6580 cp_has_mutable_p (tree type)
6582 type = strip_array_types (type);
6584 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6587 /* Apply the TYPE_QUALS to the new DECL. */
6589 cp_apply_type_quals_to_decl (int type_quals, tree decl)
6591 tree type = TREE_TYPE (decl);
6593 if (type == error_mark_node)
6596 if (TREE_CODE (type) == FUNCTION_TYPE
6597 && type_quals != TYPE_UNQUALIFIED)
6599 /* This was an error in C++98 (cv-qualifiers cannot be added to
6600 a function type), but DR 295 makes the code well-formed by
6601 dropping the extra qualifiers. */
6604 tree bad_type = build_qualified_type (type, type_quals);
6605 pedwarn ("ignoring %qV qualifiers added to function type %qT",
6609 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
6613 /* Avoid setting TREE_READONLY incorrectly. */
6614 if (/* If the object has a constructor, the constructor may modify
6616 TYPE_NEEDS_CONSTRUCTING (type)
6617 /* If the type isn't complete, we don't know yet if it will need
6619 || !COMPLETE_TYPE_P (type)
6620 /* If the type has a mutable component, that component might be
6622 || TYPE_HAS_MUTABLE_P (type))
6623 type_quals &= ~TYPE_QUAL_CONST;
6625 c_apply_type_quals_to_decl (type_quals, decl);
6628 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6629 exemplar types such that casting T1 to T2 is casting away constness
6630 if and only if there is no implicit conversion from T1 to T2. */
6633 casts_away_constness_r (tree *t1, tree *t2)
6638 /* [expr.const.cast]
6640 For multi-level pointer to members and multi-level mixed pointers
6641 and pointers to members (conv.qual), the "member" aspect of a
6642 pointer to member level is ignored when determining if a const
6643 cv-qualifier has been cast away. */
6644 /* [expr.const.cast]
6646 For two pointer types:
6648 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6649 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6652 casting from X1 to X2 casts away constness if, for a non-pointer
6653 type T there does not exist an implicit conversion (clause
6656 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6660 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6661 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
6662 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
6664 *t1 = cp_build_qualified_type (void_type_node,
6665 cp_type_quals (*t1));
6666 *t2 = cp_build_qualified_type (void_type_node,
6667 cp_type_quals (*t2));
6671 quals1 = cp_type_quals (*t1);
6672 quals2 = cp_type_quals (*t2);
6674 if (TYPE_PTRMEM_P (*t1))
6675 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
6677 *t1 = TREE_TYPE (*t1);
6678 if (TYPE_PTRMEM_P (*t2))
6679 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
6681 *t2 = TREE_TYPE (*t2);
6683 casts_away_constness_r (t1, t2);
6684 *t1 = build_pointer_type (*t1);
6685 *t2 = build_pointer_type (*t2);
6686 *t1 = cp_build_qualified_type (*t1, quals1);
6687 *t2 = cp_build_qualified_type (*t2, quals2);
6690 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6694 casts_away_constness (tree t1, tree t2)
6696 if (TREE_CODE (t2) == REFERENCE_TYPE)
6698 /* [expr.const.cast]
6700 Casting from an lvalue of type T1 to an lvalue of type T2
6701 using a reference cast casts away constness if a cast from an
6702 rvalue of type "pointer to T1" to the type "pointer to T2"
6703 casts away constness. */
6704 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6705 return casts_away_constness (build_pointer_type (t1),
6706 build_pointer_type (TREE_TYPE (t2)));
6709 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6710 /* [expr.const.cast]
6712 Casting from an rvalue of type "pointer to data member of X
6713 of type T1" to the type "pointer to data member of Y of type
6714 T2" casts away constness if a cast from an rvalue of type
6715 "pointer to T1" to the type "pointer to T2" casts away
6717 return casts_away_constness
6718 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6719 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6721 /* Casting away constness is only something that makes sense for
6722 pointer or reference types. */
6723 if (TREE_CODE (t1) != POINTER_TYPE
6724 || TREE_CODE (t2) != POINTER_TYPE)
6727 /* Top-level qualifiers don't matter. */
6728 t1 = TYPE_MAIN_VARIANT (t1);
6729 t2 = TYPE_MAIN_VARIANT (t2);
6730 casts_away_constness_r (&t1, &t2);
6731 if (!can_convert (t2, t1))
6737 /* If T is a REFERENCE_TYPE return the type to which T refers.
6738 Otherwise, return T itself. */
6741 non_reference (tree t)
6743 if (TREE_CODE (t) == REFERENCE_TYPE)
6749 /* Return nonzero if REF is an lvalue valid for this language;
6750 otherwise, print an error message and return zero. USE says
6751 how the lvalue is being used and so selects the error message. */
6754 lvalue_or_else (tree ref, enum lvalue_use use)
6756 int win = lvalue_p (ref);