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 (t != error_mark_node
231 && TYPE_NAME (t) != NULL_TREE)
233 tree x = TYPE_NAME (t);
234 if (TREE_CODE (x) != TYPE_DECL)
236 x = DECL_ORIGINAL_TYPE (x);
244 /* T1 and T2 are arithmetic or enumeration types. Return the type
245 that will result from the "usual arithmetic conversions" on T1 and
246 T2 as described in [expr]. */
249 type_after_usual_arithmetic_conversions (tree t1, tree t2)
251 enum tree_code code1 = TREE_CODE (t1);
252 enum tree_code code2 = TREE_CODE (t2);
255 /* FIXME: Attributes. */
256 gcc_assert (ARITHMETIC_TYPE_P (t1)
257 || TREE_CODE (t1) == COMPLEX_TYPE
258 || TREE_CODE (t1) == VECTOR_TYPE
259 || TREE_CODE (t1) == ENUMERAL_TYPE);
260 gcc_assert (ARITHMETIC_TYPE_P (t2)
261 || TREE_CODE (t2) == COMPLEX_TYPE
262 || TREE_CODE (t2) == VECTOR_TYPE
263 || TREE_CODE (t2) == ENUMERAL_TYPE);
265 /* In what follows, we slightly generalize the rules given in [expr] so
266 as to deal with `long long' and `complex'. First, merge the
268 attributes = (*targetm.merge_type_attributes) (t1, t2);
270 /* If one type is complex, form the common type of the non-complex
271 components, then make that complex. Use T1 or T2 if it is the
273 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
275 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
276 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
278 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
280 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
281 return build_type_attribute_variant (t1, attributes);
282 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
283 return build_type_attribute_variant (t2, attributes);
285 return build_type_attribute_variant (build_complex_type (subtype),
289 if (code1 == VECTOR_TYPE)
291 /* When we get here we should have two vectors of the same size.
292 Just prefer the unsigned one if present. */
293 if (TYPE_UNSIGNED (t1))
294 return build_type_attribute_variant (t1, attributes);
296 return build_type_attribute_variant (t2, attributes);
299 /* If only one is real, use it as the result. */
300 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
301 return build_type_attribute_variant (t1, attributes);
302 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
303 return build_type_attribute_variant (t2, attributes);
305 /* Perform the integral promotions. */
306 if (code1 != REAL_TYPE)
308 t1 = type_promotes_to (t1);
309 t2 = type_promotes_to (t2);
312 /* Both real or both integers; use the one with greater precision. */
313 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
314 return build_type_attribute_variant (t1, attributes);
315 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
316 return build_type_attribute_variant (t2, attributes);
318 /* The types are the same; no need to do anything fancy. */
319 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
320 return build_type_attribute_variant (t1, attributes);
322 if (code1 != REAL_TYPE)
324 /* If one is a sizetype, use it so size_binop doesn't blow up. */
325 if (TYPE_IS_SIZETYPE (t1) > TYPE_IS_SIZETYPE (t2))
326 return build_type_attribute_variant (t1, attributes);
327 if (TYPE_IS_SIZETYPE (t2) > TYPE_IS_SIZETYPE (t1))
328 return build_type_attribute_variant (t2, attributes);
330 /* If one is unsigned long long, then convert the other to unsigned
332 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
333 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
334 return build_type_attribute_variant (long_long_unsigned_type_node,
336 /* If one is a long long, and the other is an unsigned long, and
337 long long can represent all the values of an unsigned long, then
338 convert to a long long. Otherwise, convert to an unsigned long
339 long. Otherwise, if either operand is long long, convert the
342 Since we're here, we know the TYPE_PRECISION is the same;
343 therefore converting to long long cannot represent all the values
344 of an unsigned long, so we choose unsigned long long in that
346 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
347 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
349 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
350 ? long_long_unsigned_type_node
351 : long_long_integer_type_node);
352 return build_type_attribute_variant (t, attributes);
355 /* Go through the same procedure, but for longs. */
356 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
357 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
358 return build_type_attribute_variant (long_unsigned_type_node,
360 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
361 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
363 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
364 ? long_unsigned_type_node : long_integer_type_node);
365 return build_type_attribute_variant (t, attributes);
367 /* Otherwise prefer the unsigned one. */
368 if (TYPE_UNSIGNED (t1))
369 return build_type_attribute_variant (t1, attributes);
371 return build_type_attribute_variant (t2, attributes);
375 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
376 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
377 return build_type_attribute_variant (long_double_type_node,
379 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
380 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
381 return build_type_attribute_variant (double_type_node,
383 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
384 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
385 return build_type_attribute_variant (float_type_node,
388 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
389 the standard C++ floating-point types. Logic earlier in this
390 function has already eliminated the possibility that
391 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
392 compelling reason to choose one or the other. */
393 return build_type_attribute_variant (t1, attributes);
397 /* Subroutine of composite_pointer_type to implement the recursive
398 case. See that function for documentation fo the parameters. */
401 composite_pointer_type_r (tree t1, tree t2, const char* location)
408 /* Determine the types pointed to by T1 and T2. */
409 if (TREE_CODE (t1) == POINTER_TYPE)
411 pointee1 = TREE_TYPE (t1);
412 pointee2 = TREE_TYPE (t2);
416 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
417 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
422 Otherwise, the composite pointer type is a pointer type
423 similar (_conv.qual_) to the type of one of the operands,
424 with a cv-qualification signature (_conv.qual_) that is the
425 union of the cv-qualification signatures of the operand
427 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
428 result_type = pointee1;
429 else if ((TREE_CODE (pointee1) == POINTER_TYPE
430 && TREE_CODE (pointee2) == POINTER_TYPE)
431 || (TYPE_PTR_TO_MEMBER_P (pointee1)
432 && TYPE_PTR_TO_MEMBER_P (pointee2)))
433 result_type = composite_pointer_type_r (pointee1, pointee2, location);
436 pedwarn ("%s between distinct pointer types %qT and %qT "
439 result_type = void_type_node;
441 result_type = cp_build_qualified_type (result_type,
442 (cp_type_quals (pointee1)
443 | cp_type_quals (pointee2)));
444 /* If the original types were pointers to members, so is the
446 if (TYPE_PTR_TO_MEMBER_P (t1))
448 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
449 TYPE_PTRMEM_CLASS_TYPE (t2)))
450 pedwarn ("%s between distinct pointer types %qT and %qT "
453 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
457 result_type = build_pointer_type (result_type);
459 /* Merge the attributes. */
460 attributes = (*targetm.merge_type_attributes) (t1, t2);
461 return build_type_attribute_variant (result_type, attributes);
464 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
465 ARG1 and ARG2 are the values with those types. The LOCATION is a
466 string describing the current location, in case an error occurs.
468 This routine also implements the computation of a common type for
469 pointers-to-members as per [expr.eq]. */
472 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
473 const char* location)
480 If one operand is a null pointer constant, the composite pointer
481 type is the type of the other operand. */
482 if (null_ptr_cst_p (arg1))
484 if (null_ptr_cst_p (arg2))
491 If one of the operands has type "pointer to cv1 void*", then
492 the other has type "pointer to cv2T", and the composite pointer
493 type is "pointer to cv12 void", where cv12 is the union of cv1
496 If either type is a pointer to void, make sure it is T1. */
497 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
505 /* Now, if T1 is a pointer to void, merge the qualifiers. */
506 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
511 if (pedantic && TYPE_PTRFN_P (t2))
512 pedwarn ("ISO C++ forbids %s between pointer of type %<void *%> "
513 "and pointer-to-function", location);
515 = cp_build_qualified_type (void_type_node,
516 (cp_type_quals (TREE_TYPE (t1))
517 | cp_type_quals (TREE_TYPE (t2))));
518 result_type = build_pointer_type (result_type);
519 /* Merge the attributes. */
520 attributes = (*targetm.merge_type_attributes) (t1, t2);
521 return build_type_attribute_variant (result_type, attributes);
524 if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE
525 && TREE_CODE (t2) == POINTER_TYPE)
527 if (objc_compare_types (t1, t2, -3, NULL_TREE))
531 /* [expr.eq] permits the application of a pointer conversion to
532 bring the pointers to a common type. */
533 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
534 && CLASS_TYPE_P (TREE_TYPE (t1))
535 && CLASS_TYPE_P (TREE_TYPE (t2))
536 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
539 class1 = TREE_TYPE (t1);
540 class2 = TREE_TYPE (t2);
542 if (DERIVED_FROM_P (class1, class2))
543 t2 = (build_pointer_type
544 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
545 else if (DERIVED_FROM_P (class2, class1))
546 t1 = (build_pointer_type
547 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
550 error ("%s between distinct pointer types %qT and %qT "
551 "lacks a cast", location, t1, t2);
552 return error_mark_node;
555 /* [expr.eq] permits the application of a pointer-to-member
556 conversion to change the class type of one of the types. */
557 else if (TYPE_PTR_TO_MEMBER_P (t1)
558 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
559 TYPE_PTRMEM_CLASS_TYPE (t2)))
561 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
562 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
564 if (DERIVED_FROM_P (class1, class2))
565 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
566 else if (DERIVED_FROM_P (class2, class1))
567 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
570 error ("%s between distinct pointer-to-member types %qT and %qT "
571 "lacks a cast", location, t1, t2);
572 return error_mark_node;
576 return composite_pointer_type_r (t1, t2, location);
579 /* Return the merged type of two types.
580 We assume that comptypes has already been done and returned 1;
581 if that isn't so, this may crash.
583 This just combines attributes and default arguments; any other
584 differences would cause the two types to compare unalike. */
587 merge_types (tree t1, tree t2)
589 enum tree_code code1;
590 enum tree_code code2;
593 /* Save time if the two types are the same. */
596 if (original_type (t1) == original_type (t2))
599 /* If one type is nonsense, use the other. */
600 if (t1 == error_mark_node)
602 if (t2 == error_mark_node)
605 /* Merge the attributes. */
606 attributes = (*targetm.merge_type_attributes) (t1, t2);
608 if (TYPE_PTRMEMFUNC_P (t1))
609 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
610 if (TYPE_PTRMEMFUNC_P (t2))
611 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
613 code1 = TREE_CODE (t1);
614 code2 = TREE_CODE (t2);
620 /* For two pointers, do this recursively on the target type. */
622 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
623 int quals = cp_type_quals (t1);
625 if (code1 == POINTER_TYPE)
626 t1 = build_pointer_type (target);
628 t1 = build_reference_type (target);
629 t1 = build_type_attribute_variant (t1, attributes);
630 t1 = cp_build_qualified_type (t1, quals);
632 if (TREE_CODE (target) == METHOD_TYPE)
633 t1 = build_ptrmemfunc_type (t1);
642 quals = cp_type_quals (t1);
643 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
644 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
645 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
647 t1 = cp_build_qualified_type (t1, quals);
653 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
654 /* Save space: see if the result is identical to one of the args. */
655 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
656 return build_type_attribute_variant (t1, attributes);
657 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
658 return build_type_attribute_variant (t2, attributes);
659 /* Merge the element types, and have a size if either arg has one. */
660 t1 = build_cplus_array_type
661 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
666 /* Function types: prefer the one that specified arg types.
667 If both do, merge the arg types. Also merge the return types. */
669 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
670 tree p1 = TYPE_ARG_TYPES (t1);
671 tree p2 = TYPE_ARG_TYPES (t2);
674 /* Save space: see if the result is identical to one of the args. */
675 if (valtype == TREE_TYPE (t1) && ! p2)
676 return cp_build_type_attribute_variant (t1, attributes);
677 if (valtype == TREE_TYPE (t2) && ! p1)
678 return cp_build_type_attribute_variant (t2, attributes);
680 /* Simple way if one arg fails to specify argument types. */
681 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
683 rval = build_function_type (valtype, p2);
684 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
685 rval = build_exception_variant (rval, raises);
686 return cp_build_type_attribute_variant (rval, attributes);
688 raises = TYPE_RAISES_EXCEPTIONS (t1);
689 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
691 rval = build_function_type (valtype, p1);
693 rval = build_exception_variant (rval, raises);
694 return cp_build_type_attribute_variant (rval, attributes);
697 rval = build_function_type (valtype, commonparms (p1, p2));
698 t1 = build_exception_variant (rval, raises);
704 /* Get this value the long way, since TYPE_METHOD_BASETYPE
705 is just the main variant of this. */
706 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
707 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
710 /* If this was a member function type, get back to the
711 original type of type member function (i.e., without
712 the class instance variable up front. */
713 t1 = build_function_type (TREE_TYPE (t1),
714 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
715 t2 = build_function_type (TREE_TYPE (t2),
716 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
717 t3 = merge_types (t1, t2);
718 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
719 TYPE_ARG_TYPES (t3));
720 t1 = build_exception_variant (t3, raises);
725 /* There is no need to merge attributes into a TYPENAME_TYPE.
726 When the type is instantiated it will have whatever
727 attributes result from the instantiation. */
732 return cp_build_type_attribute_variant (t1, attributes);
735 /* Return the common type of two types.
736 We assume that comptypes has already been done and returned 1;
737 if that isn't so, this may crash.
739 This is the type for the result of most arithmetic operations
740 if the operands have the given two types. */
743 common_type (tree t1, tree t2)
745 enum tree_code code1;
746 enum tree_code code2;
748 /* If one type is nonsense, bail. */
749 if (t1 == error_mark_node || t2 == error_mark_node)
750 return error_mark_node;
752 code1 = TREE_CODE (t1);
753 code2 = TREE_CODE (t2);
755 if ((ARITHMETIC_TYPE_P (t1) || code1 == ENUMERAL_TYPE
756 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
757 && (ARITHMETIC_TYPE_P (t2) || code2 == ENUMERAL_TYPE
758 || code2 == COMPLEX_TYPE || code2 == VECTOR_TYPE))
759 return type_after_usual_arithmetic_conversions (t1, t2);
761 else if ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
762 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
763 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)))
764 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
770 /* Compare two exception specifier types for exactness or subsetness, if
771 allowed. Returns false for mismatch, true for match (same, or
774 [except.spec] "If a class X ... objects of class X or any class publicly
775 and unambiguously derived from X. Similarly, if a pointer type Y * ...
776 exceptions of type Y * or that are pointers to any type publicly and
777 unambiguously derived from Y. Otherwise a function only allows exceptions
778 that have the same type ..."
779 This does not mention cv qualifiers and is different to what throw
780 [except.throw] and catch [except.catch] will do. They will ignore the
781 top level cv qualifiers, and allow qualifiers in the pointer to class
784 We implement the letter of the standard. */
787 comp_except_types (tree a, tree b, bool exact)
789 if (same_type_p (a, b))
793 if (cp_type_quals (a) || cp_type_quals (b))
796 if (TREE_CODE (a) == POINTER_TYPE
797 && TREE_CODE (b) == POINTER_TYPE)
801 if (cp_type_quals (a) || cp_type_quals (b))
805 if (TREE_CODE (a) != RECORD_TYPE
806 || TREE_CODE (b) != RECORD_TYPE)
809 if (PUBLICLY_UNIQUELY_DERIVED_P (a, b))
815 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
816 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
817 otherwise it must be exact. Exception lists are unordered, but
818 we've already filtered out duplicates. Most lists will be in order,
819 we should try to make use of that. */
822 comp_except_specs (tree t1, tree t2, bool exact)
831 if (t1 == NULL_TREE) /* T1 is ... */
832 return t2 == NULL_TREE || !exact;
833 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
834 return t2 != NULL_TREE && !TREE_VALUE (t2);
835 if (t2 == NULL_TREE) /* T2 is ... */
837 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
840 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
841 Count how many we find, to determine exactness. For exact matching and
842 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
844 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
846 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
848 tree a = TREE_VALUE (probe);
849 tree b = TREE_VALUE (t2);
851 if (comp_except_types (a, b, exact))
853 if (probe == base && exact)
854 base = TREE_CHAIN (probe);
859 if (probe == NULL_TREE)
862 return !exact || base == NULL_TREE || length == list_length (t1);
865 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
866 [] can match [size]. */
869 comp_array_types (tree t1, tree t2, bool allow_redeclaration)
878 /* The type of the array elements must be the same. */
879 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
882 d1 = TYPE_DOMAIN (t1);
883 d2 = TYPE_DOMAIN (t2);
888 /* If one of the arrays is dimensionless, and the other has a
889 dimension, they are of different types. However, it is valid to
897 declarations for an array object can specify
898 array types that differ by the presence or absence of a major
899 array bound (_dcl.array_). */
901 return allow_redeclaration;
903 /* Check that the dimensions are the same. */
905 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
907 max1 = TYPE_MAX_VALUE (d1);
908 max2 = TYPE_MAX_VALUE (d2);
909 if (processing_template_decl && !abi_version_at_least (2)
910 && !value_dependent_expression_p (max1)
911 && !value_dependent_expression_p (max2))
913 /* With abi-1 we do not fold non-dependent array bounds, (and
914 consequently mangle them incorrectly). We must therefore
915 fold them here, to verify the domains have the same
921 if (!cp_tree_equal (max1, max2))
927 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
928 is a bitwise-or of the COMPARE_* flags. */
931 comptypes (tree t1, tree t2, int strict)
936 /* Suppress errors caused by previously reported errors. */
937 if (t1 == error_mark_node || t2 == error_mark_node)
940 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
942 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
943 current instantiation. */
944 if (TREE_CODE (t1) == TYPENAME_TYPE)
946 tree resolved = resolve_typename_type (t1, /*only_current_p=*/true);
948 if (resolved != error_mark_node)
952 if (TREE_CODE (t2) == TYPENAME_TYPE)
954 tree resolved = resolve_typename_type (t2, /*only_current_p=*/true);
956 if (resolved != error_mark_node)
960 /* If either type is the internal version of sizetype, use the
962 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
963 && TYPE_ORIG_SIZE_TYPE (t1))
964 t1 = TYPE_ORIG_SIZE_TYPE (t1);
966 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
967 && TYPE_ORIG_SIZE_TYPE (t2))
968 t2 = TYPE_ORIG_SIZE_TYPE (t2);
970 if (TYPE_PTRMEMFUNC_P (t1))
971 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
972 if (TYPE_PTRMEMFUNC_P (t2))
973 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
975 /* Different classes of types can't be compatible. */
976 if (TREE_CODE (t1) != TREE_CODE (t2))
979 /* Qualifiers must match. For array types, we will check when we
980 recur on the array element types. */
981 if (TREE_CODE (t1) != ARRAY_TYPE
982 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
984 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
987 /* Allow for two different type nodes which have essentially the same
988 definition. Note that we already checked for equality of the type
989 qualifiers (just above). */
991 if (TREE_CODE (t1) != ARRAY_TYPE
992 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
995 /* Compare the types. Break out if they could be the same. */
996 switch (TREE_CODE (t1))
998 case TEMPLATE_TEMPLATE_PARM:
999 case BOUND_TEMPLATE_TEMPLATE_PARM:
1000 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1001 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
1003 if (!comp_template_parms
1004 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1005 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1007 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1009 /* Don't check inheritance. */
1010 strict = COMPARE_STRICT;
1015 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1016 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1017 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1018 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1021 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1023 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1029 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1030 strict & ~COMPARE_REDECLARATION))
1032 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1037 case REFERENCE_TYPE:
1038 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1039 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)
1040 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1046 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1048 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1053 /* Target types must match incl. qualifiers. */
1054 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1058 case TEMPLATE_TYPE_PARM:
1059 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1060 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
1065 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1066 TYPENAME_TYPE_FULLNAME (t2)))
1068 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1072 case UNBOUND_CLASS_TEMPLATE:
1073 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1075 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1080 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1085 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1086 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1094 /* If we get here, we know that from a target independent POV the
1095 types are the same. Make sure the target attributes are also
1097 return targetm.comp_type_attributes (t1, t2);
1100 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1103 at_least_as_qualified_p (tree type1, tree type2)
1105 int q1 = cp_type_quals (type1);
1106 int q2 = cp_type_quals (type2);
1108 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1109 return (q1 & q2) == q2;
1112 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1113 more cv-qualified that TYPE1, and 0 otherwise. */
1116 comp_cv_qualification (tree type1, tree type2)
1118 int q1 = cp_type_quals (type1);
1119 int q2 = cp_type_quals (type2);
1124 if ((q1 & q2) == q2)
1126 else if ((q1 & q2) == q1)
1132 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1133 subset of the cv-qualification signature of TYPE2, and the types
1134 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1137 comp_cv_qual_signature (tree type1, tree type2)
1139 if (comp_ptr_ttypes_real (type2, type1, -1))
1141 else if (comp_ptr_ttypes_real (type1, type2, -1))
1147 /* If two types share a common base type, return that basetype.
1148 If there is not a unique most-derived base type, this function
1149 returns ERROR_MARK_NODE. */
1152 common_base_type (tree tt1, tree tt2)
1154 tree best = NULL_TREE;
1157 /* If one is a baseclass of another, that's good enough. */
1158 if (UNIQUELY_DERIVED_FROM_P (tt1, tt2))
1160 if (UNIQUELY_DERIVED_FROM_P (tt2, tt1))
1163 /* Otherwise, try to find a unique baseclass of TT1
1164 that is shared by TT2, and follow that down. */
1165 for (i = BINFO_N_BASE_BINFOS (TYPE_BINFO (tt1))-1; i >= 0; i--)
1167 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (tt1), i));
1168 tree trial = common_base_type (basetype, tt2);
1172 if (trial == error_mark_node)
1174 if (best == NULL_TREE)
1176 else if (best != trial)
1177 return error_mark_node;
1182 for (i = BINFO_N_BASE_BINFOS (TYPE_BINFO (tt2))-1; i >= 0; i--)
1184 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (tt2), i));
1185 tree trial = common_base_type (tt1, basetype);
1189 if (trial == error_mark_node)
1191 if (best == NULL_TREE)
1193 else if (best != trial)
1194 return error_mark_node;
1200 /* Subroutines of `comptypes'. */
1202 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1203 equivalent in the sense that functions with those parameter types
1204 can have equivalent types. The two lists must be equivalent,
1205 element by element. */
1208 compparms (tree parms1, tree parms2)
1212 /* An unspecified parmlist matches any specified parmlist
1213 whose argument types don't need default promotions. */
1215 for (t1 = parms1, t2 = parms2;
1217 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1219 /* If one parmlist is shorter than the other,
1220 they fail to match. */
1223 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1230 /* Process a sizeof or alignof expression where the operand is a
1234 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1239 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1240 if (type == error_mark_node)
1241 return error_mark_node;
1243 type = non_reference (type);
1244 if (TREE_CODE (type) == METHOD_TYPE)
1246 if (complain && (pedantic || warn_pointer_arith))
1247 pedwarn ("invalid application of %qs to a member function",
1248 operator_name_info[(int) op].name);
1249 value = size_one_node;
1252 dependent_p = dependent_type_p (type);
1254 complete_type (type);
1256 /* VLA types will have a non-constant size. In the body of an
1257 uninstantiated template, we don't need to try to compute the
1258 value, because the sizeof expression is not an integral
1259 constant expression in that case. And, if we do try to
1260 compute the value, we'll likely end up with SAVE_EXPRs, which
1261 the template substitution machinery does not expect to see. */
1262 || (processing_template_decl
1263 && COMPLETE_TYPE_P (type)
1264 && TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST))
1266 value = build_min (op, size_type_node, type);
1267 TREE_READONLY (value) = 1;
1271 return c_sizeof_or_alignof_type (complete_type (type),
1276 /* Process a sizeof or alignof expression where the operand is an
1280 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op)
1282 const char *op_name = operator_name_info[(int) op].name;
1284 if (e == error_mark_node)
1285 return error_mark_node;
1287 if (processing_template_decl)
1289 e = build_min (op, size_type_node, e);
1290 TREE_SIDE_EFFECTS (e) = 0;
1291 TREE_READONLY (e) = 1;
1296 if (TREE_CODE (e) == COMPONENT_REF
1297 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1298 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1300 error ("invalid application of %qs to a bit-field", op_name);
1303 else if (is_overloaded_fn (e))
1305 pedwarn ("ISO C++ forbids applying %qs to an expression of "
1306 "function type", op_name);
1309 else if (type_unknown_p (e))
1311 cxx_incomplete_type_error (e, TREE_TYPE (e));
1317 return cxx_sizeof_or_alignof_type (e, op, true);
1321 /* EXPR is being used in a context that is not a function call.
1326 The expression can be used only as the left-hand operand of a
1327 member function call.
1329 [expr.mptr.operator]
1331 If the result of .* or ->* is a function, then that result can be
1332 used only as the operand for the function call operator ().
1334 by issuing an error message if appropriate. Returns true iff EXPR
1335 violates these rules. */
1338 invalid_nonstatic_memfn_p (tree expr)
1340 if (TREE_CODE (TREE_TYPE (expr)) == METHOD_TYPE)
1342 error ("invalid use of non-static member function");
1348 /* Perform the conversions in [expr] that apply when an lvalue appears
1349 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1350 function-to-pointer conversions.
1352 In addition manifest constants are replaced by their values. */
1355 decay_conversion (tree exp)
1358 enum tree_code code;
1360 type = TREE_TYPE (exp);
1361 code = TREE_CODE (type);
1363 if (type == error_mark_node)
1364 return error_mark_node;
1366 if (type_unknown_p (exp))
1368 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1369 return error_mark_node;
1372 exp = decl_constant_value (exp);
1374 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1375 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1377 if (code == VOID_TYPE)
1379 error ("void value not ignored as it ought to be");
1380 return error_mark_node;
1382 if (invalid_nonstatic_memfn_p (exp))
1383 return error_mark_node;
1384 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1385 return build_unary_op (ADDR_EXPR, exp, 0);
1386 if (code == ARRAY_TYPE)
1391 if (TREE_CODE (exp) == INDIRECT_REF)
1392 return build_nop (build_pointer_type (TREE_TYPE (type)),
1393 TREE_OPERAND (exp, 0));
1395 if (TREE_CODE (exp) == COMPOUND_EXPR)
1397 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1398 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1399 TREE_OPERAND (exp, 0), op1);
1403 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1405 error ("invalid use of non-lvalue array");
1406 return error_mark_node;
1409 ptrtype = build_pointer_type (TREE_TYPE (type));
1411 if (TREE_CODE (exp) == VAR_DECL)
1413 if (!cxx_mark_addressable (exp))
1414 return error_mark_node;
1415 adr = build_nop (ptrtype, build_address (exp));
1418 /* This way is better for a COMPONENT_REF since it can
1419 simplify the offset for a component. */
1420 adr = build_unary_op (ADDR_EXPR, exp, 1);
1421 return cp_convert (ptrtype, adr);
1424 /* [basic.lval]: Class rvalues can have cv-qualified types; non-class
1425 rvalues always have cv-unqualified types. */
1426 if (! CLASS_TYPE_P (type))
1427 exp = cp_convert (TYPE_MAIN_VARIANT (type), exp);
1433 default_conversion (tree exp)
1435 exp = decay_conversion (exp);
1437 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1438 exp = perform_integral_promotions (exp);
1443 /* EXPR is an expression with an integral or enumeration type.
1444 Perform the integral promotions in [conv.prom], and return the
1448 perform_integral_promotions (tree expr)
1453 type = TREE_TYPE (expr);
1454 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1455 promoted_type = type_promotes_to (type);
1456 if (type != promoted_type)
1457 expr = cp_convert (promoted_type, expr);
1461 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1465 inline_conversion (tree exp)
1467 if (TREE_CODE (exp) == FUNCTION_DECL)
1468 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1473 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1474 decay_conversion to one. */
1477 string_conv_p (tree totype, tree exp, int warn)
1481 if (! flag_const_strings || TREE_CODE (totype) != POINTER_TYPE)
1484 t = TREE_TYPE (totype);
1485 if (!same_type_p (t, char_type_node)
1486 && !same_type_p (t, wchar_type_node))
1489 if (TREE_CODE (exp) == STRING_CST)
1491 /* Make sure that we don't try to convert between char and wchar_t. */
1492 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1497 /* Is this a string constant which has decayed to 'const char *'? */
1498 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1499 if (!same_type_p (TREE_TYPE (exp), t))
1502 if (TREE_CODE (exp) != ADDR_EXPR
1503 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1507 /* This warning is not very useful, as it complains about printf. */
1508 if (warn && warn_write_strings)
1509 warning (0, "deprecated conversion from string constant to %qT'", totype);
1514 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1515 can, for example, use as an lvalue. This code used to be in
1516 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1517 expressions, where we're dealing with aggregates. But now it's again only
1518 called from unary_complex_lvalue. The case (in particular) that led to
1519 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1523 rationalize_conditional_expr (enum tree_code code, tree t)
1525 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1526 the first operand is always the one to be used if both operands
1527 are equal, so we know what conditional expression this used to be. */
1528 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1530 /* The following code is incorrect if either operand side-effects. */
1531 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0))
1532 && !TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)));
1534 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1535 ? LE_EXPR : GE_EXPR),
1536 TREE_OPERAND (t, 0),
1537 TREE_OPERAND (t, 1),
1538 /*overloaded_p=*/NULL),
1539 build_unary_op (code, TREE_OPERAND (t, 0), 0),
1540 build_unary_op (code, TREE_OPERAND (t, 1), 0));
1544 build_conditional_expr (TREE_OPERAND (t, 0),
1545 build_unary_op (code, TREE_OPERAND (t, 1), 0),
1546 build_unary_op (code, TREE_OPERAND (t, 2), 0));
1549 /* Given the TYPE of an anonymous union field inside T, return the
1550 FIELD_DECL for the field. If not found return NULL_TREE. Because
1551 anonymous unions can nest, we must also search all anonymous unions
1552 that are directly reachable. */
1555 lookup_anon_field (tree t, tree type)
1559 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1561 if (TREE_STATIC (field))
1563 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1566 /* If we find it directly, return the field. */
1567 if (DECL_NAME (field) == NULL_TREE
1568 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1573 /* Otherwise, it could be nested, search harder. */
1574 if (DECL_NAME (field) == NULL_TREE
1575 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1577 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1585 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1586 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1587 non-NULL, it indicates the path to the base used to name MEMBER.
1588 If PRESERVE_REFERENCE is true, the expression returned will have
1589 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1590 returned will have the type referred to by the reference.
1592 This function does not perform access control; that is either done
1593 earlier by the parser when the name of MEMBER is resolved to MEMBER
1594 itself, or later when overload resolution selects one of the
1595 functions indicated by MEMBER. */
1598 build_class_member_access_expr (tree object, tree member,
1599 tree access_path, bool preserve_reference)
1603 tree result = NULL_TREE;
1605 if (object == error_mark_node || member == error_mark_node)
1606 return error_mark_node;
1608 gcc_assert (DECL_P (member) || BASELINK_P (member));
1612 The type of the first expression shall be "class object" (of a
1614 object_type = TREE_TYPE (object);
1615 if (!currently_open_class (object_type)
1616 && !complete_type_or_else (object_type, object))
1617 return error_mark_node;
1618 if (!CLASS_TYPE_P (object_type))
1620 error ("request for member %qD in %qE, which is of non-class type %qT",
1621 member, object, object_type);
1622 return error_mark_node;
1625 /* The standard does not seem to actually say that MEMBER must be a
1626 member of OBJECT_TYPE. However, that is clearly what is
1628 if (DECL_P (member))
1630 member_scope = DECL_CLASS_CONTEXT (member);
1632 if (TREE_DEPRECATED (member))
1633 warn_deprecated_use (member);
1636 member_scope = BINFO_TYPE (BASELINK_BINFO (member));
1637 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1638 presently be the anonymous union. Go outwards until we find a
1639 type related to OBJECT_TYPE. */
1640 while (ANON_AGGR_TYPE_P (member_scope)
1641 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1643 member_scope = TYPE_CONTEXT (member_scope);
1644 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1646 if (TREE_CODE (member) == FIELD_DECL)
1647 error ("invalid use of nonstatic data member %qE", member);
1649 error ("%qD is not a member of %qT", member, object_type);
1650 return error_mark_node;
1653 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1654 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1655 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1657 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1659 object = build_indirect_ref (temp, NULL);
1662 /* In [expr.ref], there is an explicit list of the valid choices for
1663 MEMBER. We check for each of those cases here. */
1664 if (TREE_CODE (member) == VAR_DECL)
1666 /* A static data member. */
1668 /* If OBJECT has side-effects, they are supposed to occur. */
1669 if (TREE_SIDE_EFFECTS (object))
1670 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1672 else if (TREE_CODE (member) == FIELD_DECL)
1674 /* A non-static data member. */
1679 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1680 && integer_zerop (TREE_OPERAND (object, 0)));
1682 /* Convert OBJECT to the type of MEMBER. */
1683 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1684 TYPE_MAIN_VARIANT (member_scope)))
1689 binfo = lookup_base (access_path ? access_path : object_type,
1690 member_scope, ba_unique, &kind);
1691 if (binfo == error_mark_node)
1692 return error_mark_node;
1694 /* It is invalid to try to get to a virtual base of a
1695 NULL object. The most common cause is invalid use of
1697 if (null_object_p && kind == bk_via_virtual)
1699 error ("invalid access to non-static data member %qD of "
1702 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
1703 return error_mark_node;
1706 /* Convert to the base. */
1707 object = build_base_path (PLUS_EXPR, object, binfo,
1709 /* If we found the base successfully then we should be able
1710 to convert to it successfully. */
1711 gcc_assert (object != error_mark_node);
1714 /* Complain about other invalid uses of offsetof, even though they will
1715 give the right answer. Note that we complain whether or not they
1716 actually used the offsetof macro, since there's no way to know at this
1717 point. So we just give a warning, instead of a pedwarn. */
1718 /* Do not produce this warning for base class field references, because
1719 we know for a fact that didn't come from offsetof. This does occur
1720 in various testsuite cases where a null object is passed where a
1721 vtable access is required. */
1722 if (null_object_p && warn_invalid_offsetof
1723 && CLASSTYPE_NON_POD_P (object_type)
1724 && !DECL_FIELD_IS_BASE (member)
1725 && !skip_evaluation)
1727 warning (0, "invalid access to non-static data member %qD of NULL object",
1729 warning (0, "(perhaps the %<offsetof%> macro was used incorrectly)");
1732 /* If MEMBER is from an anonymous aggregate, we have converted
1733 OBJECT so that it refers to the class containing the
1734 anonymous union. Generate a reference to the anonymous union
1735 itself, and recur to find MEMBER. */
1736 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
1737 /* When this code is called from build_field_call, the
1738 object already has the type of the anonymous union.
1739 That is because the COMPONENT_REF was already
1740 constructed, and was then disassembled before calling
1741 build_field_call. After the function-call code is
1742 cleaned up, this waste can be eliminated. */
1743 && (!same_type_ignoring_top_level_qualifiers_p
1744 (TREE_TYPE (object), DECL_CONTEXT (member))))
1746 tree anonymous_union;
1748 anonymous_union = lookup_anon_field (TREE_TYPE (object),
1749 DECL_CONTEXT (member));
1750 object = build_class_member_access_expr (object,
1752 /*access_path=*/NULL_TREE,
1753 preserve_reference);
1756 /* Compute the type of the field, as described in [expr.ref]. */
1757 type_quals = TYPE_UNQUALIFIED;
1758 member_type = TREE_TYPE (member);
1759 if (TREE_CODE (member_type) != REFERENCE_TYPE)
1761 type_quals = (cp_type_quals (member_type)
1762 | cp_type_quals (object_type));
1764 /* A field is const (volatile) if the enclosing object, or the
1765 field itself, is const (volatile). But, a mutable field is
1766 not const, even within a const object. */
1767 if (DECL_MUTABLE_P (member))
1768 type_quals &= ~TYPE_QUAL_CONST;
1769 member_type = cp_build_qualified_type (member_type, type_quals);
1772 result = build3 (COMPONENT_REF, member_type, object, member,
1774 result = fold_if_not_in_template (result);
1776 /* Mark the expression const or volatile, as appropriate. Even
1777 though we've dealt with the type above, we still have to mark the
1778 expression itself. */
1779 if (type_quals & TYPE_QUAL_CONST)
1780 TREE_READONLY (result) = 1;
1781 if (type_quals & TYPE_QUAL_VOLATILE)
1782 TREE_THIS_VOLATILE (result) = 1;
1784 else if (BASELINK_P (member))
1786 /* The member is a (possibly overloaded) member function. */
1790 /* If the MEMBER is exactly one static member function, then we
1791 know the type of the expression. Otherwise, we must wait
1792 until overload resolution has been performed. */
1793 functions = BASELINK_FUNCTIONS (member);
1794 if (TREE_CODE (functions) == FUNCTION_DECL
1795 && DECL_STATIC_FUNCTION_P (functions))
1796 type = TREE_TYPE (functions);
1798 type = unknown_type_node;
1799 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1800 base. That will happen when the function is called. */
1801 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
1803 else if (TREE_CODE (member) == CONST_DECL)
1805 /* The member is an enumerator. */
1807 /* If OBJECT has side-effects, they are supposed to occur. */
1808 if (TREE_SIDE_EFFECTS (object))
1809 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
1814 error ("invalid use of %qD", member);
1815 return error_mark_node;
1818 if (!preserve_reference)
1821 If E2 is declared to have type "reference to T", then ... the
1822 type of E1.E2 is T. */
1823 result = convert_from_reference (result);
1828 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1829 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1832 lookup_destructor (tree object, tree scope, tree dtor_name)
1834 tree object_type = TREE_TYPE (object);
1835 tree dtor_type = TREE_OPERAND (dtor_name, 0);
1838 if (scope && !check_dtor_name (scope, dtor_type))
1840 error ("qualified type %qT does not match destructor name ~%qT",
1842 return error_mark_node;
1844 if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
1846 error ("the type being destroyed is %qT, but the destructor refers to %qT",
1847 TYPE_MAIN_VARIANT (object_type), dtor_type);
1848 return error_mark_node;
1850 expr = lookup_member (dtor_type, complete_dtor_identifier,
1851 /*protect=*/1, /*want_type=*/false);
1852 expr = (adjust_result_of_qualified_name_lookup
1853 (expr, dtor_type, object_type));
1857 /* An expression of the form "A::template B" has been resolved to
1858 DECL. Issue a diagnostic if B is not a template or template
1862 check_template_keyword (tree decl)
1864 /* The standard says:
1868 If a name prefixed by the keyword template is not a member
1869 template, the program is ill-formed.
1871 DR 228 removed the restriction that the template be a member
1874 DR 96, if accepted would add the further restriction that explicit
1875 template arguments must be provided if the template keyword is
1876 used, but, as of 2005-10-16, that DR is still in "drafting". If
1877 this DR is accepted, then the semantic checks here can be
1878 simplified, as the entity named must in fact be a template
1879 specialization, rather than, as at present, a set of overloaded
1880 functions containing at least one template function. */
1881 if (TREE_CODE (decl) != TEMPLATE_DECL
1882 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
1884 if (!is_overloaded_fn (decl))
1885 pedwarn ("%qD is not a template", decl);
1890 if (BASELINK_P (fns))
1891 fns = BASELINK_FUNCTIONS (fns);
1894 tree fn = OVL_CURRENT (fns);
1895 if (TREE_CODE (fn) == TEMPLATE_DECL
1896 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
1898 if (TREE_CODE (fn) == FUNCTION_DECL
1899 && DECL_USE_TEMPLATE (fn)
1900 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
1902 fns = OVL_NEXT (fns);
1905 pedwarn ("%qD is not a template", decl);
1910 /* This function is called by the parser to process a class member
1911 access expression of the form OBJECT.NAME. NAME is a node used by
1912 the parser to represent a name; it is not yet a DECL. It may,
1913 however, be a BASELINK where the BASELINK_FUNCTIONS is a
1914 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
1915 there is no reason to do the lookup twice, so the parser keeps the
1916 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
1917 be a template via the use of the "A::template B" syntax. */
1920 finish_class_member_access_expr (tree object, tree name, bool template_p)
1925 tree access_path = NULL_TREE;
1926 tree orig_object = object;
1927 tree orig_name = name;
1929 if (object == error_mark_node || name == error_mark_node)
1930 return error_mark_node;
1932 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
1933 if (!objc_is_public (object, name))
1934 return error_mark_node;
1936 object_type = TREE_TYPE (object);
1938 if (processing_template_decl)
1940 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
1941 dependent_type_p (object_type)
1942 /* If NAME is just an IDENTIFIER_NODE, then the expression
1944 || TREE_CODE (object) == IDENTIFIER_NODE
1945 /* If NAME is "f<args>", where either 'f' or 'args' is
1946 dependent, then the expression is dependent. */
1947 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
1948 && dependent_template_id_p (TREE_OPERAND (name, 0),
1949 TREE_OPERAND (name, 1)))
1950 /* If NAME is "T::X" where "T" is dependent, then the
1951 expression is dependent. */
1952 || (TREE_CODE (name) == SCOPE_REF
1953 && TYPE_P (TREE_OPERAND (name, 0))
1954 && dependent_type_p (TREE_OPERAND (name, 0))))
1955 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
1956 object = build_non_dependent_expr (object);
1961 The type of the first expression shall be "class object" (of a
1963 if (!currently_open_class (object_type)
1964 && !complete_type_or_else (object_type, object))
1965 return error_mark_node;
1966 if (!CLASS_TYPE_P (object_type))
1968 error ("request for member %qD in %qE, which is of non-class type %qT",
1969 name, object, object_type);
1970 return error_mark_node;
1973 if (BASELINK_P (name))
1974 /* A member function that has already been looked up. */
1978 bool is_template_id = false;
1979 tree template_args = NULL_TREE;
1982 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
1984 is_template_id = true;
1985 template_args = TREE_OPERAND (name, 1);
1986 name = TREE_OPERAND (name, 0);
1988 if (TREE_CODE (name) == OVERLOAD)
1989 name = DECL_NAME (get_first_fn (name));
1990 else if (DECL_P (name))
1991 name = DECL_NAME (name);
1994 if (TREE_CODE (name) == SCOPE_REF)
1996 /* A qualified name. The qualifying class or namespace `S'
1997 has already been looked up; it is either a TYPE or a
1999 scope = TREE_OPERAND (name, 0);
2000 name = TREE_OPERAND (name, 1);
2002 /* If SCOPE is a namespace, then the qualified name does not
2003 name a member of OBJECT_TYPE. */
2004 if (TREE_CODE (scope) == NAMESPACE_DECL)
2006 error ("%<%D::%D%> is not a member of %qT",
2007 scope, name, object_type);
2008 return error_mark_node;
2011 gcc_assert (CLASS_TYPE_P (scope));
2012 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2013 || TREE_CODE (name) == BIT_NOT_EXPR);
2015 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2016 access_path = lookup_base (object_type, scope, ba_check, NULL);
2017 if (access_path == error_mark_node)
2018 return error_mark_node;
2021 error ("%qT is not a base of %qT", scope, object_type);
2022 return error_mark_node;
2028 access_path = object_type;
2031 if (TREE_CODE (name) == BIT_NOT_EXPR)
2032 member = lookup_destructor (object, scope, name);
2035 /* Look up the member. */
2036 member = lookup_member (access_path, name, /*protect=*/1,
2037 /*want_type=*/false);
2038 if (member == NULL_TREE)
2040 error ("%qD has no member named %qE", object_type, name);
2041 return error_mark_node;
2043 if (member == error_mark_node)
2044 return error_mark_node;
2049 tree template = member;
2051 if (BASELINK_P (template))
2052 template = lookup_template_function (template, template_args);
2055 error ("%qD is not a member template function", name);
2056 return error_mark_node;
2061 if (TREE_DEPRECATED (member))
2062 warn_deprecated_use (member);
2065 check_template_keyword (member);
2067 expr = build_class_member_access_expr (object, member, access_path,
2068 /*preserve_reference=*/false);
2069 if (processing_template_decl && expr != error_mark_node)
2071 if (BASELINK_P (member))
2073 if (TREE_CODE (orig_name) == SCOPE_REF)
2074 BASELINK_QUALIFIED_P (member) = 1;
2077 return build_min_non_dep (COMPONENT_REF, expr,
2078 orig_object, orig_name,
2085 /* Return an expression for the MEMBER_NAME field in the internal
2086 representation of PTRMEM, a pointer-to-member function. (Each
2087 pointer-to-member function type gets its own RECORD_TYPE so it is
2088 more convenient to access the fields by name than by FIELD_DECL.)
2089 This routine converts the NAME to a FIELD_DECL and then creates the
2090 node for the complete expression. */
2093 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2099 /* This code is a stripped down version of
2100 build_class_member_access_expr. It does not work to use that
2101 routine directly because it expects the object to be of class
2103 ptrmem_type = TREE_TYPE (ptrmem);
2104 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2105 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2106 /*want_type=*/false);
2107 member_type = cp_build_qualified_type (TREE_TYPE (member),
2108 cp_type_quals (ptrmem_type));
2109 return fold_build3 (COMPONENT_REF, member_type,
2110 ptrmem, member, NULL_TREE);
2113 /* Given an expression PTR for a pointer, return an expression
2114 for the value pointed to.
2115 ERRORSTRING is the name of the operator to appear in error messages.
2117 This function may need to overload OPERATOR_FNNAME.
2118 Must also handle REFERENCE_TYPEs for C++. */
2121 build_x_indirect_ref (tree expr, const char *errorstring)
2123 tree orig_expr = expr;
2126 if (processing_template_decl)
2128 if (type_dependent_expression_p (expr))
2129 return build_min_nt (INDIRECT_REF, expr);
2130 expr = build_non_dependent_expr (expr);
2133 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2134 NULL_TREE, /*overloaded_p=*/NULL);
2136 rval = build_indirect_ref (expr, errorstring);
2138 if (processing_template_decl && rval != error_mark_node)
2139 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2145 build_indirect_ref (tree ptr, const char *errorstring)
2149 if (ptr == error_mark_node)
2150 return error_mark_node;
2152 if (ptr == current_class_ptr)
2153 return current_class_ref;
2155 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2156 ? ptr : decay_conversion (ptr));
2157 type = TREE_TYPE (pointer);
2159 if (POINTER_TYPE_P (type))
2163 If the type of the expression is "pointer to T," the type
2164 of the result is "T."
2166 We must use the canonical variant because certain parts of
2167 the back end, like fold, do pointer comparisons between
2169 tree t = canonical_type_variant (TREE_TYPE (type));
2171 if (VOID_TYPE_P (t))
2173 /* A pointer to incomplete type (other than cv void) can be
2174 dereferenced [expr.unary.op]/1 */
2175 error ("%qT is not a pointer-to-object type", type);
2176 return error_mark_node;
2178 else if (TREE_CODE (pointer) == ADDR_EXPR
2179 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2180 /* The POINTER was something like `&x'. We simplify `*&x' to
2182 return TREE_OPERAND (pointer, 0);
2185 tree ref = build1 (INDIRECT_REF, t, pointer);
2187 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2188 so that we get the proper error message if the result is used
2189 to assign to. Also, &* is supposed to be a no-op. */
2190 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2191 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2192 TREE_SIDE_EFFECTS (ref)
2193 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2197 /* `pointer' won't be an error_mark_node if we were given a
2198 pointer to member, so it's cool to check for this here. */
2199 else if (TYPE_PTR_TO_MEMBER_P (type))
2200 error ("invalid use of %qs on pointer to member", errorstring);
2201 else if (pointer != error_mark_node)
2204 error ("invalid type argument of %qs", errorstring);
2206 error ("invalid type argument");
2208 return error_mark_node;
2211 /* This handles expressions of the form "a[i]", which denotes
2214 This is logically equivalent in C to *(a+i), but we may do it differently.
2215 If A is a variable or a member, we generate a primitive ARRAY_REF.
2216 This avoids forcing the array out of registers, and can work on
2217 arrays that are not lvalues (for example, members of structures returned
2220 If INDEX is of some user-defined type, it must be converted to
2221 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2222 will inherit the type of the array, which will be some pointer type. */
2225 build_array_ref (tree array, tree idx)
2229 error ("subscript missing in array reference");
2230 return error_mark_node;
2233 if (TREE_TYPE (array) == error_mark_node
2234 || TREE_TYPE (idx) == error_mark_node)
2235 return error_mark_node;
2237 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2239 switch (TREE_CODE (array))
2243 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2244 return build2 (COMPOUND_EXPR, TREE_TYPE (value),
2245 TREE_OPERAND (array, 0), value);
2249 return build_conditional_expr
2250 (TREE_OPERAND (array, 0),
2251 build_array_ref (TREE_OPERAND (array, 1), idx),
2252 build_array_ref (TREE_OPERAND (array, 2), idx));
2258 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2262 /* Subscripting with type char is likely to lose
2263 on a machine where chars are signed.
2264 So warn on any machine, but optionally.
2265 Don't warn for unsigned char since that type is safe.
2266 Don't warn for signed char because anyone who uses that
2267 must have done so deliberately. */
2268 if (warn_char_subscripts
2269 && TYPE_MAIN_VARIANT (TREE_TYPE (idx)) == char_type_node)
2270 warning (0, "array subscript has type %<char%>");
2272 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2274 error ("array subscript is not an integer");
2275 return error_mark_node;
2278 /* Apply integral promotions *after* noticing character types.
2279 (It is unclear why we do these promotions -- the standard
2280 does not say that we should. In fact, the natural thing would
2281 seem to be to convert IDX to ptrdiff_t; we're performing
2282 pointer arithmetic.) */
2283 idx = perform_integral_promotions (idx);
2285 /* An array that is indexed by a non-constant
2286 cannot be stored in a register; we must be able to do
2287 address arithmetic on its address.
2288 Likewise an array of elements of variable size. */
2289 if (TREE_CODE (idx) != INTEGER_CST
2290 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2291 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2294 if (!cxx_mark_addressable (array))
2295 return error_mark_node;
2298 /* An array that is indexed by a constant value which is not within
2299 the array bounds cannot be stored in a register either; because we
2300 would get a crash in store_bit_field/extract_bit_field when trying
2301 to access a non-existent part of the register. */
2302 if (TREE_CODE (idx) == INTEGER_CST
2303 && TYPE_DOMAIN (TREE_TYPE (array))
2304 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2306 if (!cxx_mark_addressable (array))
2307 return error_mark_node;
2310 if (pedantic && !lvalue_p (array))
2311 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2313 /* Note in C++ it is valid to subscript a `register' array, since
2314 it is valid to take the address of something with that
2315 storage specification. */
2319 while (TREE_CODE (foo) == COMPONENT_REF)
2320 foo = TREE_OPERAND (foo, 0);
2321 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2322 warning (0, "subscripting array declared %<register%>");
2325 type = TREE_TYPE (TREE_TYPE (array));
2326 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2327 /* Array ref is const/volatile if the array elements are
2328 or if the array is.. */
2329 TREE_READONLY (rval)
2330 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2331 TREE_SIDE_EFFECTS (rval)
2332 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2333 TREE_THIS_VOLATILE (rval)
2334 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2335 return require_complete_type (fold_if_not_in_template (rval));
2339 tree ar = default_conversion (array);
2340 tree ind = default_conversion (idx);
2342 /* Put the integer in IND to simplify error checking. */
2343 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2350 if (ar == error_mark_node)
2353 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2355 error ("subscripted value is neither array nor pointer");
2356 return error_mark_node;
2358 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2360 error ("array subscript is not an integer");
2361 return error_mark_node;
2364 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2369 /* Resolve a pointer to member function. INSTANCE is the object
2370 instance to use, if the member points to a virtual member.
2372 This used to avoid checking for virtual functions if basetype
2373 has no virtual functions, according to an earlier ANSI draft.
2374 With the final ISO C++ rules, such an optimization is
2375 incorrect: A pointer to a derived member can be static_cast
2376 to pointer-to-base-member, as long as the dynamic object
2377 later has the right member. */
2380 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2382 if (TREE_CODE (function) == OFFSET_REF)
2383 function = TREE_OPERAND (function, 1);
2385 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2387 tree idx, delta, e1, e2, e3, vtbl, basetype;
2388 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2390 tree instance_ptr = *instance_ptrptr;
2391 tree instance_save_expr = 0;
2392 if (instance_ptr == error_mark_node)
2394 if (TREE_CODE (function) == PTRMEM_CST)
2396 /* Extracting the function address from a pmf is only
2397 allowed with -Wno-pmf-conversions. It only works for
2399 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2400 e1 = convert (fntype, e1);
2405 error ("object missing in use of %qE", function);
2406 return error_mark_node;
2410 if (TREE_SIDE_EFFECTS (instance_ptr))
2411 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2413 if (TREE_SIDE_EFFECTS (function))
2414 function = save_expr (function);
2416 /* Start by extracting all the information from the PMF itself. */
2417 e3 = pfn_from_ptrmemfunc (function);
2418 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2419 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2420 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2422 case ptrmemfunc_vbit_in_pfn:
2423 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2424 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2427 case ptrmemfunc_vbit_in_delta:
2428 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2429 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2436 /* Convert down to the right base before using the instance. A
2437 special case is that in a pointer to member of class C, C may
2438 be incomplete. In that case, the function will of course be
2439 a member of C, and no conversion is required. In fact,
2440 lookup_base will fail in that case, because incomplete
2441 classes do not have BINFOs. */
2442 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2443 if (!same_type_ignoring_top_level_qualifiers_p
2444 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2446 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2447 basetype, ba_check, NULL);
2448 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2450 if (instance_ptr == error_mark_node)
2451 return error_mark_node;
2453 /* ...and then the delta in the PMF. */
2454 instance_ptr = build2 (PLUS_EXPR, TREE_TYPE (instance_ptr),
2455 instance_ptr, delta);
2457 /* Hand back the adjusted 'this' argument to our caller. */
2458 *instance_ptrptr = instance_ptr;
2460 /* Next extract the vtable pointer from the object. */
2461 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2463 vtbl = build_indirect_ref (vtbl, NULL);
2465 /* Finally, extract the function pointer from the vtable. */
2466 e2 = fold_build2 (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx);
2467 e2 = build_indirect_ref (e2, NULL);
2468 TREE_CONSTANT (e2) = 1;
2469 TREE_INVARIANT (e2) = 1;
2471 /* When using function descriptors, the address of the
2472 vtable entry is treated as a function pointer. */
2473 if (TARGET_VTABLE_USES_DESCRIPTORS)
2474 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2475 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2477 TREE_TYPE (e2) = TREE_TYPE (e3);
2478 e1 = build_conditional_expr (e1, e2, e3);
2480 /* Make sure this doesn't get evaluated first inside one of the
2481 branches of the COND_EXPR. */
2482 if (instance_save_expr)
2483 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2484 instance_save_expr, e1);
2492 build_function_call (tree function, tree params)
2494 tree fntype, fndecl;
2495 tree coerced_params;
2496 tree name = NULL_TREE;
2498 tree original = function;
2500 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2501 expressions, like those used for ObjC messenger dispatches. */
2502 function = objc_rewrite_function_call (function, params);
2504 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2505 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2506 if (TREE_CODE (function) == NOP_EXPR
2507 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2508 function = TREE_OPERAND (function, 0);
2510 if (TREE_CODE (function) == FUNCTION_DECL)
2512 name = DECL_NAME (function);
2514 mark_used (function);
2517 /* Convert anything with function type to a pointer-to-function. */
2518 if (pedantic && DECL_MAIN_P (function))
2519 pedwarn ("ISO C++ forbids calling %<::main%> from within program");
2521 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2522 (because calling an inline function does not mean the function
2523 needs to be separately compiled). */
2525 if (DECL_INLINE (function))
2526 function = inline_conversion (function);
2528 function = build_addr_func (function);
2534 function = build_addr_func (function);
2537 if (function == error_mark_node)
2538 return error_mark_node;
2540 fntype = TREE_TYPE (function);
2542 if (TYPE_PTRMEMFUNC_P (fntype))
2544 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2545 "function in %<%E (...)%>",
2547 return error_mark_node;
2550 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2551 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2553 if (!((TREE_CODE (fntype) == POINTER_TYPE
2554 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2556 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2558 error ("%qE cannot be used as a function", original);
2559 return error_mark_node;
2562 /* fntype now gets the type of function pointed to. */
2563 fntype = TREE_TYPE (fntype);
2565 /* Convert the parameters to the types declared in the
2566 function prototype, or apply default promotions. */
2568 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2569 params, fndecl, LOOKUP_NORMAL);
2570 if (coerced_params == error_mark_node)
2571 return error_mark_node;
2573 /* Check for errors in format strings and inappropriately
2576 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params,
2577 TYPE_ARG_TYPES (fntype));
2579 return build_cxx_call (function, coerced_params);
2582 /* Convert the actual parameter expressions in the list VALUES
2583 to the types in the list TYPELIST.
2584 If parmdecls is exhausted, or when an element has NULL as its type,
2585 perform the default conversions.
2587 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2589 This is also where warnings about wrong number of args are generated.
2591 Return a list of expressions for the parameters as converted.
2593 Both VALUES and the returned value are chains of TREE_LIST nodes
2594 with the elements of the list in the TREE_VALUE slots of those nodes.
2596 In C++, unspecified trailing parameters can be filled in with their
2597 default arguments, if such were specified. Do so here. */
2600 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2602 tree typetail, valtail;
2603 tree result = NULL_TREE;
2604 const char *called_thing = 0;
2607 /* Argument passing is always copy-initialization. */
2608 flags |= LOOKUP_ONLYCONVERTING;
2612 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2614 if (DECL_NAME (fndecl) == NULL_TREE
2615 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2616 called_thing = "constructor";
2618 called_thing = "member function";
2621 called_thing = "function";
2624 for (valtail = values, typetail = typelist;
2626 valtail = TREE_CHAIN (valtail), i++)
2628 tree type = typetail ? TREE_VALUE (typetail) : 0;
2629 tree val = TREE_VALUE (valtail);
2631 if (val == error_mark_node || type == error_mark_node)
2632 return error_mark_node;
2634 if (type == void_type_node)
2638 error ("too many arguments to %s %q+#D", called_thing, fndecl);
2639 error ("at this point in file");
2642 error ("too many arguments to function");
2643 /* In case anybody wants to know if this argument
2646 TREE_TYPE (tree_last (result)) = error_mark_node;
2650 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2651 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2652 if (TREE_CODE (val) == NOP_EXPR
2653 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2654 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2655 val = TREE_OPERAND (val, 0);
2657 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2659 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2660 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2661 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2662 val = decay_conversion (val);
2665 if (val == error_mark_node)
2666 return error_mark_node;
2670 /* Formal parm type is specified by a function prototype. */
2673 if (!COMPLETE_TYPE_P (complete_type (type)))
2676 error ("parameter %P of %qD has incomplete type %qT",
2679 error ("parameter %P has incomplete type %qT", i, type);
2680 parmval = error_mark_node;
2684 parmval = convert_for_initialization
2685 (NULL_TREE, type, val, flags,
2686 "argument passing", fndecl, i);
2687 parmval = convert_for_arg_passing (type, parmval);
2690 if (parmval == error_mark_node)
2691 return error_mark_node;
2693 result = tree_cons (NULL_TREE, parmval, result);
2697 if (fndecl && DECL_BUILT_IN (fndecl)
2698 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2699 /* Don't do ellipsis conversion for __built_in_constant_p
2700 as this will result in spurious warnings for non-POD
2702 val = require_complete_type (val);
2704 val = convert_arg_to_ellipsis (val);
2706 result = tree_cons (NULL_TREE, val, result);
2710 typetail = TREE_CHAIN (typetail);
2713 if (typetail != 0 && typetail != void_list_node)
2715 /* See if there are default arguments that can be used. */
2716 if (TREE_PURPOSE (typetail)
2717 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2719 for (; typetail != void_list_node; ++i)
2722 = convert_default_arg (TREE_VALUE (typetail),
2723 TREE_PURPOSE (typetail),
2726 if (parmval == error_mark_node)
2727 return error_mark_node;
2729 result = tree_cons (0, parmval, result);
2730 typetail = TREE_CHAIN (typetail);
2731 /* ends with `...'. */
2732 if (typetail == NULL_TREE)
2740 error ("too few arguments to %s %q+#D", called_thing, fndecl);
2741 error ("at this point in file");
2744 error ("too few arguments to function");
2745 return error_mark_node;
2749 return nreverse (result);
2752 /* Build a binary-operation expression, after performing default
2753 conversions on the operands. CODE is the kind of expression to build. */
2756 build_x_binary_op (enum tree_code code, tree arg1, tree arg2,
2766 if (processing_template_decl)
2768 if (type_dependent_expression_p (arg1)
2769 || type_dependent_expression_p (arg2))
2770 return build_min_nt (code, arg1, arg2);
2771 arg1 = build_non_dependent_expr (arg1);
2772 arg2 = build_non_dependent_expr (arg2);
2775 if (code == DOTSTAR_EXPR)
2776 expr = build_m_component_ref (arg1, arg2);
2778 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
2781 if (processing_template_decl && expr != error_mark_node)
2782 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
2787 /* Build a binary-operation expression without default conversions.
2788 CODE is the kind of expression to build.
2789 This function differs from `build' in several ways:
2790 the data type of the result is computed and recorded in it,
2791 warnings are generated if arg data types are invalid,
2792 special handling for addition and subtraction of pointers is known,
2793 and some optimization is done (operations on narrow ints
2794 are done in the narrower type when that gives the same result).
2795 Constant folding is also done before the result is returned.
2797 Note that the operands will never have enumeral types
2798 because either they have just had the default conversions performed
2799 or they have both just been converted to some other type in which
2800 the arithmetic is to be done.
2802 C++: must do special pointer arithmetic when implementing
2803 multiple inheritance, and deal with pointer to member functions. */
2806 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2807 int convert_p ATTRIBUTE_UNUSED)
2810 enum tree_code code0, code1;
2812 const char *invalid_op_diag;
2814 /* Expression code to give to the expression when it is built.
2815 Normally this is CODE, which is what the caller asked for,
2816 but in some special cases we change it. */
2817 enum tree_code resultcode = code;
2819 /* Data type in which the computation is to be performed.
2820 In the simplest cases this is the common type of the arguments. */
2821 tree result_type = NULL;
2823 /* Nonzero means operands have already been type-converted
2824 in whatever way is necessary.
2825 Zero means they need to be converted to RESULT_TYPE. */
2828 /* Nonzero means create the expression with this type, rather than
2830 tree build_type = 0;
2832 /* Nonzero means after finally constructing the expression
2833 convert it to this type. */
2834 tree final_type = 0;
2838 /* Nonzero if this is an operation like MIN or MAX which can
2839 safely be computed in short if both args are promoted shorts.
2840 Also implies COMMON.
2841 -1 indicates a bitwise operation; this makes a difference
2842 in the exact conditions for when it is safe to do the operation
2843 in a narrower mode. */
2846 /* Nonzero if this is a comparison operation;
2847 if both args are promoted shorts, compare the original shorts.
2848 Also implies COMMON. */
2849 int short_compare = 0;
2851 /* Nonzero if this is a right-shift operation, which can be computed on the
2852 original short and then promoted if the operand is a promoted short. */
2853 int short_shift = 0;
2855 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2858 /* True if both operands have arithmetic type. */
2859 bool arithmetic_types_p;
2861 /* Apply default conversions. */
2865 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2866 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2867 || code == TRUTH_XOR_EXPR)
2869 if (!really_overloaded_fn (op0))
2870 op0 = decay_conversion (op0);
2871 if (!really_overloaded_fn (op1))
2872 op1 = decay_conversion (op1);
2876 if (!really_overloaded_fn (op0))
2877 op0 = default_conversion (op0);
2878 if (!really_overloaded_fn (op1))
2879 op1 = default_conversion (op1);
2882 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2883 STRIP_TYPE_NOPS (op0);
2884 STRIP_TYPE_NOPS (op1);
2886 /* DTRT if one side is an overloaded function, but complain about it. */
2887 if (type_unknown_p (op0))
2889 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
2890 if (t != error_mark_node)
2892 pedwarn ("assuming cast to type %qT from overloaded function",
2897 if (type_unknown_p (op1))
2899 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
2900 if (t != error_mark_node)
2902 pedwarn ("assuming cast to type %qT from overloaded function",
2908 type0 = TREE_TYPE (op0);
2909 type1 = TREE_TYPE (op1);
2911 /* The expression codes of the data types of the arguments tell us
2912 whether the arguments are integers, floating, pointers, etc. */
2913 code0 = TREE_CODE (type0);
2914 code1 = TREE_CODE (type1);
2916 /* If an error was already reported for one of the arguments,
2917 avoid reporting another error. */
2919 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
2920 return error_mark_node;
2922 if ((invalid_op_diag
2923 = targetm.invalid_binary_op (code, type0, type1)))
2925 error (invalid_op_diag);
2926 return error_mark_node;
2932 /* Subtraction of two similar pointers.
2933 We must subtract them as integers, then divide by object size. */
2934 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
2935 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
2937 return pointer_diff (op0, op1, common_type (type0, type1));
2938 /* In all other cases except pointer - int, the usual arithmetic
2940 else if (!(code0 == POINTER_TYPE && code1 == INTEGER_TYPE))
2945 /* The pointer - int case is just like pointer + int; fall
2948 if ((code0 == POINTER_TYPE || code1 == POINTER_TYPE)
2949 && (code0 == INTEGER_TYPE || code1 == INTEGER_TYPE))
2953 ptr_operand = ((code0 == POINTER_TYPE) ? op0 : op1);
2954 int_operand = ((code0 == INTEGER_TYPE) ? op0 : op1);
2955 if (processing_template_decl)
2957 result_type = TREE_TYPE (ptr_operand);
2960 return cp_pointer_int_sum (code,
2971 case TRUNC_DIV_EXPR:
2973 case FLOOR_DIV_EXPR:
2974 case ROUND_DIV_EXPR:
2975 case EXACT_DIV_EXPR:
2976 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2977 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
2978 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2979 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
2981 enum tree_code tcode0 = code0, tcode1 = code1;
2983 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
2984 warning (0, "division by zero in %<%E / 0%>", op0);
2985 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
2986 warning (0, "division by zero in %<%E / 0.%>", op0);
2988 if (tcode0 == COMPLEX_TYPE || tcode0 == VECTOR_TYPE)
2989 tcode0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
2990 if (tcode1 == COMPLEX_TYPE || tcode1 == VECTOR_TYPE)
2991 tcode1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
2993 if (!(tcode0 == INTEGER_TYPE && tcode1 == INTEGER_TYPE))
2994 resultcode = RDIV_EXPR;
2996 /* When dividing two signed integers, we have to promote to int.
2997 unless we divide by a constant != -1. Note that default
2998 conversion will have been performed on the operands at this
2999 point, so we have to dig out the original type to find out if
3001 shorten = ((TREE_CODE (op0) == NOP_EXPR
3002 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3003 || (TREE_CODE (op1) == INTEGER_CST
3004 && ! integer_all_onesp (op1)));
3013 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3014 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE))
3018 case TRUNC_MOD_EXPR:
3019 case FLOOR_MOD_EXPR:
3020 if (code1 == INTEGER_TYPE && integer_zerop (op1))
3021 warning (0, "division by zero in %<%E %% 0%>", op0);
3022 else if (code1 == REAL_TYPE && real_zerop (op1))
3023 warning (0, "division by zero in %<%E %% 0.%>", op0);
3025 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3027 /* Although it would be tempting to shorten always here, that loses
3028 on some targets, since the modulo instruction is undefined if the
3029 quotient can't be represented in the computation mode. We shorten
3030 only if unsigned or if dividing by something we know != -1. */
3031 shorten = ((TREE_CODE (op0) == NOP_EXPR
3032 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3033 || (TREE_CODE (op1) == INTEGER_CST
3034 && ! integer_all_onesp (op1)));
3039 case TRUTH_ANDIF_EXPR:
3040 case TRUTH_ORIF_EXPR:
3041 case TRUTH_AND_EXPR:
3043 result_type = boolean_type_node;
3046 /* Shift operations: result has same type as first operand;
3047 always convert second operand to int.
3048 Also set SHORT_SHIFT if shifting rightward. */
3051 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3053 result_type = type0;
3054 if (TREE_CODE (op1) == INTEGER_CST)
3056 if (tree_int_cst_lt (op1, integer_zero_node))
3057 warning (0, "right shift count is negative");
3060 if (! integer_zerop (op1))
3062 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3063 warning (0, "right 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. */
3076 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3078 result_type = type0;
3079 if (TREE_CODE (op1) == INTEGER_CST)
3081 if (tree_int_cst_lt (op1, integer_zero_node))
3082 warning (0, "left shift count is negative");
3083 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3084 warning (0, "left shift count >= width of type");
3086 /* Convert the shift-count to an integer, regardless of
3087 size of value being shifted. */
3088 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3089 op1 = cp_convert (integer_type_node, op1);
3090 /* Avoid converting op1 to result_type later. */
3097 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3099 result_type = type0;
3100 if (TREE_CODE (op1) == INTEGER_CST)
3102 if (tree_int_cst_lt (op1, integer_zero_node))
3103 warning (0, "%s rotate count is negative",
3104 (code == LROTATE_EXPR) ? "left" : "right");
3105 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3106 warning (0, "%s rotate count >= width of type",
3107 (code == LROTATE_EXPR) ? "left" : "right");
3109 /* Convert the shift-count to an integer, regardless of
3110 size of value being shifted. */
3111 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3112 op1 = cp_convert (integer_type_node, op1);
3118 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
3119 warning (0, "comparing floating point with == or != is unsafe");
3121 build_type = boolean_type_node;
3122 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3123 || code0 == COMPLEX_TYPE)
3124 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3125 || code1 == COMPLEX_TYPE))
3127 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3128 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3129 result_type = composite_pointer_type (type0, type1, op0, op1,
3131 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3132 && null_ptr_cst_p (op1))
3133 result_type = type0;
3134 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3135 && null_ptr_cst_p (op0))
3136 result_type = type1;
3137 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3139 result_type = type0;
3140 error ("ISO C++ forbids comparison between pointer and integer");
3142 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3144 result_type = type1;
3145 error ("ISO C++ forbids comparison between pointer and integer");
3147 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3149 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3150 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3151 result_type = TREE_TYPE (op0);
3153 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3154 return cp_build_binary_op (code, op1, op0);
3155 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
3156 && same_type_p (type0, type1))
3158 /* E will be the final comparison. */
3160 /* E1 and E2 are for scratch. */
3168 if (TREE_SIDE_EFFECTS (op0))
3169 op0 = save_expr (op0);
3170 if (TREE_SIDE_EFFECTS (op1))
3171 op1 = save_expr (op1);
3176 && (!op0.pfn || op0.delta == op1.delta))
3178 The reason for the `!op0.pfn' bit is that a NULL
3179 pointer-to-member is any member with a zero PFN; the
3180 DELTA field is unspecified. */
3181 pfn0 = pfn_from_ptrmemfunc (op0);
3182 pfn1 = pfn_from_ptrmemfunc (op1);
3183 delta0 = build_ptrmemfunc_access_expr (op0,
3185 delta1 = build_ptrmemfunc_access_expr (op1,
3187 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
3188 e2 = cp_build_binary_op (EQ_EXPR,
3190 cp_convert (TREE_TYPE (pfn0),
3191 integer_zero_node));
3192 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
3193 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3194 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3195 if (code == EQ_EXPR)
3197 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3201 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3202 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3204 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3205 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3213 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3214 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3216 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3217 result_type = composite_pointer_type (type0, type1, op0, op1,
3225 build_type = boolean_type_node;
3226 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3227 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3229 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3230 result_type = composite_pointer_type (type0, type1, op0, op1,
3232 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3233 && integer_zerop (op1))
3234 result_type = type0;
3235 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3236 && integer_zerop (op0))
3237 result_type = type1;
3238 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3240 result_type = type0;
3241 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3243 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3245 result_type = type1;
3246 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3250 case UNORDERED_EXPR:
3257 build_type = integer_type_node;
3258 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3260 error ("unordered comparison on non-floating point argument");
3261 return error_mark_node;
3270 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3271 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3272 || code1 == COMPLEX_TYPE)))
3273 arithmetic_types_p = 1;
3276 arithmetic_types_p = 0;
3277 /* Vector arithmetic is only allowed when both sides are vectors. */
3278 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3280 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3281 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3284 binary_op_error (code);
3285 return error_mark_node;
3287 arithmetic_types_p = 1;
3290 /* Determine the RESULT_TYPE, if it is not already known. */
3292 && arithmetic_types_p
3293 && (shorten || common || short_compare))
3294 result_type = common_type (type0, type1);
3298 error ("invalid operands of types %qT and %qT to binary %qO",
3299 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3300 return error_mark_node;
3303 /* If we're in a template, the only thing we need to know is the
3305 if (processing_template_decl)
3306 return build2 (resultcode,
3307 build_type ? build_type : result_type,
3310 if (arithmetic_types_p)
3312 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3314 /* For certain operations (which identify themselves by shorten != 0)
3315 if both args were extended from the same smaller type,
3316 do the arithmetic in that type and then extend.
3318 shorten !=0 and !=1 indicates a bitwise operation.
3319 For them, this optimization is safe only if
3320 both args are zero-extended or both are sign-extended.
3321 Otherwise, we might change the result.
3322 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3323 but calculated in (unsigned short) it would be (unsigned short)-1. */
3325 if (shorten && none_complex)
3327 int unsigned0, unsigned1;
3328 tree arg0 = get_narrower (op0, &unsigned0);
3329 tree arg1 = get_narrower (op1, &unsigned1);
3330 /* UNS is 1 if the operation to be done is an unsigned one. */
3331 int uns = TYPE_UNSIGNED (result_type);
3334 final_type = result_type;
3336 /* Handle the case that OP0 does not *contain* a conversion
3337 but it *requires* conversion to FINAL_TYPE. */
3339 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3340 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
3341 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3342 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
3344 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3346 /* For bitwise operations, signedness of nominal type
3347 does not matter. Consider only how operands were extended. */
3351 /* Note that in all three cases below we refrain from optimizing
3352 an unsigned operation on sign-extended args.
3353 That would not be valid. */
3355 /* Both args variable: if both extended in same way
3356 from same width, do it in that width.
3357 Do it unsigned if args were zero-extended. */
3358 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3359 < TYPE_PRECISION (result_type))
3360 && (TYPE_PRECISION (TREE_TYPE (arg1))
3361 == TYPE_PRECISION (TREE_TYPE (arg0)))
3362 && unsigned0 == unsigned1
3363 && (unsigned0 || !uns))
3364 result_type = c_common_signed_or_unsigned_type
3365 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3366 else if (TREE_CODE (arg0) == INTEGER_CST
3367 && (unsigned1 || !uns)
3368 && (TYPE_PRECISION (TREE_TYPE (arg1))
3369 < TYPE_PRECISION (result_type))
3370 && (type = c_common_signed_or_unsigned_type
3371 (unsigned1, TREE_TYPE (arg1)),
3372 int_fits_type_p (arg0, type)))
3374 else if (TREE_CODE (arg1) == INTEGER_CST
3375 && (unsigned0 || !uns)
3376 && (TYPE_PRECISION (TREE_TYPE (arg0))
3377 < TYPE_PRECISION (result_type))
3378 && (type = c_common_signed_or_unsigned_type
3379 (unsigned0, TREE_TYPE (arg0)),
3380 int_fits_type_p (arg1, type)))
3384 /* Shifts can be shortened if shifting right. */
3389 tree arg0 = get_narrower (op0, &unsigned_arg);
3391 final_type = result_type;
3393 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3394 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
3396 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3397 /* We can shorten only if the shift count is less than the
3398 number of bits in the smaller type size. */
3399 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3400 /* If arg is sign-extended and then unsigned-shifted,
3401 we can simulate this with a signed shift in arg's type
3402 only if the extended result is at least twice as wide
3403 as the arg. Otherwise, the shift could use up all the
3404 ones made by sign-extension and bring in zeros.
3405 We can't optimize that case at all, but in most machines
3406 it never happens because available widths are 2**N. */
3407 && (!TYPE_UNSIGNED (final_type)
3409 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3410 <= TYPE_PRECISION (result_type))))
3412 /* Do an unsigned shift if the operand was zero-extended. */
3414 = c_common_signed_or_unsigned_type (unsigned_arg,
3416 /* Convert value-to-be-shifted to that type. */
3417 if (TREE_TYPE (op0) != result_type)
3418 op0 = cp_convert (result_type, op0);
3423 /* Comparison operations are shortened too but differently.
3424 They identify themselves by setting short_compare = 1. */
3428 /* Don't write &op0, etc., because that would prevent op0
3429 from being kept in a register.
3430 Instead, make copies of the our local variables and
3431 pass the copies by reference, then copy them back afterward. */
3432 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3433 enum tree_code xresultcode = resultcode;
3435 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3437 return cp_convert (boolean_type_node, val);
3438 op0 = xop0, op1 = xop1;
3440 resultcode = xresultcode;
3443 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3444 && warn_sign_compare
3445 /* Do not warn until the template is instantiated; we cannot
3446 bound the ranges of the arguments until that point. */
3447 && !processing_template_decl)
3449 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
3450 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3452 int unsignedp0, unsignedp1;
3453 tree primop0 = get_narrower (op0, &unsignedp0);
3454 tree primop1 = get_narrower (op1, &unsignedp1);
3456 /* Check for comparison of different enum types. */
3457 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3458 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3459 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3460 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3462 warning (0, "comparison between types %q#T and %q#T",
3463 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3466 /* Give warnings for comparisons between signed and unsigned
3467 quantities that may fail. */
3468 /* Do the checking based on the original operand trees, so that
3469 casts will be considered, but default promotions won't be. */
3471 /* Do not warn if the comparison is being done in a signed type,
3472 since the signed type will only be chosen if it can represent
3473 all the values of the unsigned type. */
3474 if (!TYPE_UNSIGNED (result_type))
3476 /* Do not warn if both operands are unsigned. */
3477 else if (op0_signed == op1_signed)
3479 /* Do not warn if the signed quantity is an unsuffixed
3480 integer literal (or some static constant expression
3481 involving such literals or a conditional expression
3482 involving such literals) and it is non-negative. */
3483 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3484 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3486 /* Do not warn if the comparison is an equality operation,
3487 the unsigned quantity is an integral constant and it does
3488 not use the most significant bit of result_type. */
3489 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3490 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3491 && int_fits_type_p (orig_op1, c_common_signed_type
3493 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3494 && int_fits_type_p (orig_op0, c_common_signed_type
3498 warning (0, "comparison between signed and unsigned integer expressions");
3500 /* Warn if two unsigned values are being compared in a size
3501 larger than their original size, and one (and only one) is the
3502 result of a `~' operator. This comparison will always fail.
3504 Also warn if one operand is a constant, and the constant does not
3505 have all bits set that are set in the ~ operand when it is
3508 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3509 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3511 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3512 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3513 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3514 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3516 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3519 HOST_WIDE_INT constant, mask;
3523 if (host_integerp (primop0, 0))
3526 unsignedp = unsignedp1;
3527 constant = tree_low_cst (primop0, 0);
3532 unsignedp = unsignedp0;
3533 constant = tree_low_cst (primop1, 0);
3536 bits = TYPE_PRECISION (TREE_TYPE (primop));
3537 if (bits < TYPE_PRECISION (result_type)
3538 && bits < HOST_BITS_PER_LONG && unsignedp)
3540 mask = (~ (HOST_WIDE_INT) 0) << bits;
3541 if ((mask & constant) != mask)
3542 warning (0, "comparison of promoted ~unsigned with constant");
3545 else if (unsignedp0 && unsignedp1
3546 && (TYPE_PRECISION (TREE_TYPE (primop0))
3547 < TYPE_PRECISION (result_type))
3548 && (TYPE_PRECISION (TREE_TYPE (primop1))
3549 < TYPE_PRECISION (result_type)))
3550 warning (0, "comparison of promoted ~unsigned with unsigned");
3555 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3556 Then the expression will be built.
3557 It will be given type FINAL_TYPE if that is nonzero;
3558 otherwise, it will be given type RESULT_TYPE. */
3560 /* Issue warnings about peculiar, but valid, uses of NULL. */
3561 if (/* It's reasonable to use pointer values as operands of &&
3562 and ||, so NULL is no exception. */
3563 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3564 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3565 (orig_op0 == null_node
3566 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3567 /* Or vice versa. */
3568 || (orig_op1 == null_node
3569 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3570 /* Or, both are NULL and the operation was not a comparison. */
3571 || (orig_op0 == null_node && orig_op1 == null_node
3572 && code != EQ_EXPR && code != NE_EXPR)))
3573 /* Some sort of arithmetic operation involving NULL was
3574 performed. Note that pointer-difference and pointer-addition
3575 have already been handled above, and so we don't end up here in
3577 warning (0, "NULL used in arithmetic");
3581 if (TREE_TYPE (op0) != result_type)
3582 op0 = cp_convert (result_type, op0);
3583 if (TREE_TYPE (op1) != result_type)
3584 op1 = cp_convert (result_type, op1);
3586 if (op0 == error_mark_node || op1 == error_mark_node)
3587 return error_mark_node;
3590 if (build_type == NULL_TREE)
3591 build_type = result_type;
3593 result = build2 (resultcode, build_type, op0, op1);
3594 result = fold_if_not_in_template (result);
3595 if (final_type != 0)
3596 result = cp_convert (final_type, result);
3600 /* Return a tree for the sum or difference (RESULTCODE says which)
3601 of pointer PTROP and integer INTOP. */
3604 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
3606 tree res_type = TREE_TYPE (ptrop);
3608 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3609 in certain circumstance (when it's valid to do so). So we need
3610 to make sure it's complete. We don't need to check here, if we
3611 can actually complete it at all, as those checks will be done in
3612 pointer_int_sum() anyway. */
3613 complete_type (TREE_TYPE (res_type));
3615 return pointer_int_sum (resultcode, ptrop,
3616 fold_if_not_in_template (intop));
3619 /* Return a tree for the difference of pointers OP0 and OP1.
3620 The resulting tree has type int. */
3623 pointer_diff (tree op0, tree op1, tree ptrtype)
3626 tree restype = ptrdiff_type_node;
3627 tree target_type = TREE_TYPE (ptrtype);
3629 if (!complete_type_or_else (target_type, NULL_TREE))
3630 return error_mark_node;
3632 if (pedantic || warn_pointer_arith)
3634 if (TREE_CODE (target_type) == VOID_TYPE)
3635 pedwarn ("ISO C++ forbids using pointer of type %<void *%> in subtraction");
3636 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3637 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3638 if (TREE_CODE (target_type) == METHOD_TYPE)
3639 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3642 /* First do the subtraction as integers;
3643 then drop through to build the divide operator. */
3645 op0 = cp_build_binary_op (MINUS_EXPR,
3646 cp_convert (restype, op0),
3647 cp_convert (restype, op1));
3649 /* This generates an error if op1 is a pointer to an incomplete type. */
3650 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3651 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3653 op1 = (TYPE_PTROB_P (ptrtype)
3654 ? size_in_bytes (target_type)
3655 : integer_one_node);
3657 /* Do the division. */
3659 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3660 return fold_if_not_in_template (result);
3663 /* Construct and perhaps optimize a tree representation
3664 for a unary operation. CODE, a tree_code, specifies the operation
3665 and XARG is the operand. */
3668 build_x_unary_op (enum tree_code code, tree xarg)
3670 tree orig_expr = xarg;
3674 if (processing_template_decl)
3676 if (type_dependent_expression_p (xarg))
3677 return build_min_nt (code, xarg, NULL_TREE);
3679 xarg = build_non_dependent_expr (xarg);
3684 /* [expr.unary.op] says:
3686 The address of an object of incomplete type can be taken.
3688 (And is just the ordinary address operator, not an overloaded
3689 "operator &".) However, if the type is a template
3690 specialization, we must complete the type at this point so that
3691 an overloaded "operator &" will be available if required. */
3692 if (code == ADDR_EXPR
3693 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3694 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
3695 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
3696 || (TREE_CODE (xarg) == OFFSET_REF)))
3697 /* Don't look for a function. */;
3699 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
3700 /*overloaded_p=*/NULL);
3701 if (!exp && code == ADDR_EXPR)
3703 /* A pointer to member-function can be formed only by saying
3705 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3706 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3708 if (TREE_CODE (xarg) != OFFSET_REF
3709 || !TYPE_P (TREE_OPERAND (xarg, 0)))
3711 error ("invalid use of %qE to form a pointer-to-member-function",
3713 if (TREE_CODE (xarg) != OFFSET_REF)
3714 inform (" a qualified-id is required");
3715 return error_mark_node;
3719 error ("parenthesis around %qE cannot be used to form a"
3720 " pointer-to-member-function",
3722 PTRMEM_OK_P (xarg) = 1;
3726 if (TREE_CODE (xarg) == OFFSET_REF)
3728 ptrmem = PTRMEM_OK_P (xarg);
3730 if (!ptrmem && !flag_ms_extensions
3731 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3733 /* A single non-static member, make sure we don't allow a
3734 pointer-to-member. */
3735 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
3736 TREE_OPERAND (xarg, 0),
3737 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3738 PTRMEM_OK_P (xarg) = ptrmem;
3741 else if (TREE_CODE (xarg) == TARGET_EXPR)
3742 warning (0, "taking address of temporary");
3743 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3746 if (processing_template_decl && exp != error_mark_node)
3747 exp = build_min_non_dep (code, exp, orig_expr,
3748 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
3749 if (TREE_CODE (exp) == ADDR_EXPR)
3750 PTRMEM_OK_P (exp) = ptrmem;
3754 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3755 constants, where a null value is represented by an INTEGER_CST of
3759 cp_truthvalue_conversion (tree expr)
3761 tree type = TREE_TYPE (expr);
3762 if (TYPE_PTRMEM_P (type))
3763 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3765 return c_common_truthvalue_conversion (expr);
3768 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3771 condition_conversion (tree expr)
3774 if (processing_template_decl)
3776 t = perform_implicit_conversion (boolean_type_node, expr);
3777 t = fold_build_cleanup_point_expr (boolean_type_node, t);
3781 /* Return an ADDR_EXPR giving the address of T. This function
3782 attempts no optimizations or simplifications; it is a low-level
3786 build_address (tree t)
3790 if (error_operand_p (t) || !cxx_mark_addressable (t))
3791 return error_mark_node;
3793 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
3798 /* Return a NOP_EXPR converting EXPR to TYPE. */
3801 build_nop (tree type, tree expr)
3803 if (type == error_mark_node || error_operand_p (expr))
3805 return build1 (NOP_EXPR, type, expr);
3808 /* C++: Must handle pointers to members.
3810 Perhaps type instantiation should be extended to handle conversion
3811 from aggregates to types we don't yet know we want? (Or are those
3812 cases typically errors which should be reported?)
3814 NOCONVERT nonzero suppresses the default promotions
3815 (such as from short to int). */
3818 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3820 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3823 const char *errstring = NULL;
3825 const char *invalid_op_diag;
3827 if (arg == error_mark_node)
3828 return error_mark_node;
3830 if ((invalid_op_diag
3831 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
3836 error (invalid_op_diag);
3837 return error_mark_node;
3842 case UNARY_PLUS_EXPR:
3845 int flags = WANT_ARITH | WANT_ENUM;
3846 /* Unary plus (but not unary minus) is allowed on pointers. */
3847 if (code == UNARY_PLUS_EXPR)
3848 flags |= WANT_POINTER;
3849 arg = build_expr_type_conversion (flags, arg, true);
3851 errstring = (code == NEGATE_EXPR
3852 ? "wrong type argument to unary minus"
3853 : "wrong type argument to unary plus");
3856 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3857 arg = perform_integral_promotions (arg);
3859 /* Make sure the result is not an lvalue: a unary plus or minus
3860 expression is always a rvalue. */
3867 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3871 arg = default_conversion (arg);
3873 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM
3876 errstring = "wrong type argument to bit-complement";
3877 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3878 arg = perform_integral_promotions (arg);
3882 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3883 errstring = "wrong type argument to abs";
3884 else if (!noconvert)
3885 arg = default_conversion (arg);
3889 /* Conjugating a real value is a no-op, but allow it anyway. */
3890 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3891 errstring = "wrong type argument to conjugation";
3892 else if (!noconvert)
3893 arg = default_conversion (arg);
3896 case TRUTH_NOT_EXPR:
3897 arg = perform_implicit_conversion (boolean_type_node, arg);
3898 val = invert_truthvalue (arg);
3899 if (arg != error_mark_node)
3901 errstring = "in argument to unary !";
3908 if (TREE_CODE (arg) == COMPLEX_CST)
3909 return TREE_REALPART (arg);
3910 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3912 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3913 return fold_if_not_in_template (arg);
3919 if (TREE_CODE (arg) == COMPLEX_CST)
3920 return TREE_IMAGPART (arg);
3921 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3923 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
3924 return fold_if_not_in_template (arg);
3927 return cp_convert (TREE_TYPE (arg), integer_zero_node);
3929 case PREINCREMENT_EXPR:
3930 case POSTINCREMENT_EXPR:
3931 case PREDECREMENT_EXPR:
3932 case POSTDECREMENT_EXPR:
3933 /* Handle complex lvalues (when permitted)
3934 by reduction to simpler cases. */
3936 val = unary_complex_lvalue (code, arg);
3940 /* Increment or decrement the real part of the value,
3941 and don't change the imaginary part. */
3942 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3946 arg = stabilize_reference (arg);
3947 real = build_unary_op (REALPART_EXPR, arg, 1);
3948 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
3949 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
3950 build_unary_op (code, real, 1), imag);
3953 /* Report invalid types. */
3955 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
3958 if (code == PREINCREMENT_EXPR)
3959 errstring ="no pre-increment operator for type";
3960 else if (code == POSTINCREMENT_EXPR)
3961 errstring ="no post-increment operator for type";
3962 else if (code == PREDECREMENT_EXPR)
3963 errstring ="no pre-decrement operator for type";
3965 errstring ="no post-decrement operator for type";
3969 /* Report something read-only. */
3971 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
3972 || TREE_READONLY (arg))
3973 readonly_error (arg, ((code == PREINCREMENT_EXPR
3974 || code == POSTINCREMENT_EXPR)
3975 ? "increment" : "decrement"),
3980 tree result_type = TREE_TYPE (arg);
3982 arg = get_unwidened (arg, 0);
3983 argtype = TREE_TYPE (arg);
3985 /* ARM $5.2.5 last annotation says this should be forbidden. */
3986 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
3987 pedwarn ("ISO C++ forbids %sing an enum",
3988 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3989 ? "increment" : "decrement");
3991 /* Compute the increment. */
3993 if (TREE_CODE (argtype) == POINTER_TYPE)
3995 tree type = complete_type (TREE_TYPE (argtype));
3997 if (!COMPLETE_OR_VOID_TYPE_P (type))
3998 error ("cannot %s a pointer to incomplete type %qT",
3999 ((code == PREINCREMENT_EXPR
4000 || code == POSTINCREMENT_EXPR)
4001 ? "increment" : "decrement"), TREE_TYPE (argtype));
4002 else if ((pedantic || warn_pointer_arith)
4003 && !TYPE_PTROB_P (argtype))
4004 pedwarn ("ISO C++ forbids %sing a pointer of type %qT",
4005 ((code == PREINCREMENT_EXPR
4006 || code == POSTINCREMENT_EXPR)
4007 ? "increment" : "decrement"), argtype);
4008 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4011 inc = integer_one_node;
4013 inc = cp_convert (argtype, inc);
4015 /* Handle incrementing a cast-expression. */
4017 switch (TREE_CODE (arg))
4022 case FIX_TRUNC_EXPR:
4023 case FIX_FLOOR_EXPR:
4024 case FIX_ROUND_EXPR:
4027 tree incremented, modify, value, compound;
4028 if (! lvalue_p (arg) && pedantic)
4029 pedwarn ("cast to non-reference type used as lvalue");
4030 arg = stabilize_reference (arg);
4031 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
4034 value = save_expr (arg);
4035 incremented = build2 (((code == PREINCREMENT_EXPR
4036 || code == POSTINCREMENT_EXPR)
4037 ? PLUS_EXPR : MINUS_EXPR),
4038 argtype, value, inc);
4040 modify = build_modify_expr (arg, NOP_EXPR, incremented);
4041 compound = build2 (COMPOUND_EXPR, TREE_TYPE (arg),
4044 /* Eliminate warning about unused result of + or -. */
4045 TREE_NO_WARNING (compound) = 1;
4053 /* Complain about anything else that is not a true lvalue. */
4054 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4055 || code == POSTINCREMENT_EXPR)
4056 ? lv_increment : lv_decrement)))
4057 return error_mark_node;
4059 /* Forbid using -- on `bool'. */
4060 if (TREE_TYPE (arg) == boolean_type_node)
4062 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4064 error ("invalid use of %<--%> on bool variable %qD", arg);
4065 return error_mark_node;
4067 val = boolean_increment (code, arg);
4070 val = build2 (code, TREE_TYPE (arg), arg, inc);
4072 TREE_SIDE_EFFECTS (val) = 1;
4073 return cp_convert (result_type, val);
4077 /* Note that this operation never does default_conversion
4078 regardless of NOCONVERT. */
4080 argtype = lvalue_type (arg);
4082 if (TREE_CODE (arg) == OFFSET_REF)
4085 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4087 tree type = build_pointer_type (TREE_TYPE (argtype));
4088 arg = build1 (CONVERT_EXPR, type, arg);
4091 else if (pedantic && DECL_MAIN_P (arg))
4093 pedwarn ("ISO C++ forbids taking address of function %<::main%>");
4095 /* Let &* cancel out to simplify resulting code. */
4096 if (TREE_CODE (arg) == INDIRECT_REF)
4098 /* We don't need to have `current_class_ptr' wrapped in a
4099 NON_LVALUE_EXPR node. */
4100 if (arg == current_class_ref)
4101 return current_class_ptr;
4103 arg = TREE_OPERAND (arg, 0);
4104 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4106 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4107 arg = build1 (CONVERT_EXPR, type, arg);
4110 /* Don't let this be an lvalue. */
4115 /* Uninstantiated types are all functions. Taking the
4116 address of a function is a no-op, so just return the
4119 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4120 || !IDENTIFIER_OPNAME_P (arg));
4122 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4123 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4125 /* They're trying to take the address of a unique non-static
4126 member function. This is ill-formed (except in MS-land),
4127 but let's try to DTRT.
4128 Note: We only handle unique functions here because we don't
4129 want to complain if there's a static overload; non-unique
4130 cases will be handled by instantiate_type. But we need to
4131 handle this case here to allow casts on the resulting PMF.
4132 We could defer this in non-MS mode, but it's easier to give
4133 a useful error here. */
4135 /* Inside constant member functions, the `this' pointer
4136 contains an extra const qualifier. TYPE_MAIN_VARIANT
4137 is used here to remove this const from the diagnostics
4138 and the created OFFSET_REF. */
4139 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4140 tree name = DECL_NAME (get_first_fn (TREE_OPERAND (arg, 1)));
4142 if (! flag_ms_extensions)
4144 if (current_class_type
4145 && TREE_OPERAND (arg, 0) == current_class_ref)
4146 /* An expression like &memfn. */
4147 pedwarn ("ISO C++ forbids taking the address of an unqualified"
4148 " or parenthesized non-static member function to form"
4149 " a pointer to member function. Say %<&%T::%D%>",
4152 pedwarn ("ISO C++ forbids taking the address of a bound member"
4153 " function to form a pointer to member function."
4157 arg = build_offset_ref (base, name, /*address_p=*/true);
4161 if (type_unknown_p (arg))
4162 return build1 (ADDR_EXPR, unknown_type_node, arg);
4164 /* Handle complex lvalues (when permitted)
4165 by reduction to simpler cases. */
4166 val = unary_complex_lvalue (code, arg);
4170 switch (TREE_CODE (arg))
4175 case FIX_TRUNC_EXPR:
4176 case FIX_FLOOR_EXPR:
4177 case FIX_ROUND_EXPR:
4179 if (! lvalue_p (arg) && pedantic)
4180 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4184 arg = OVL_CURRENT (arg);
4188 /* Turn a reference to a non-static data member into a
4189 pointer-to-member. */
4194 if (!PTRMEM_OK_P (arg))
4195 return build_unary_op (code, arg, 0);
4197 t = TREE_OPERAND (arg, 1);
4198 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4200 error ("cannot create pointer to reference member %qD", t);
4201 return error_mark_node;
4204 type = build_ptrmem_type (context_for_name_lookup (t),
4206 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4214 /* Anything not already handled and not a true memory reference
4216 if (TREE_CODE (argtype) != FUNCTION_TYPE
4217 && TREE_CODE (argtype) != METHOD_TYPE
4218 && TREE_CODE (arg) != OFFSET_REF
4219 /* Permit users to take the address of a compound-literal
4220 with sufficient simple elements. */
4221 && !(COMPOUND_LITERAL_P (arg) && TREE_STATIC (arg))
4222 && !lvalue_or_else (arg, lv_addressof))
4223 return error_mark_node;
4225 if (argtype != error_mark_node)
4226 argtype = build_pointer_type (argtype);
4228 /* In a template, we are processing a non-dependent expression
4229 so we can just form an ADDR_EXPR with the correct type. */
4230 if (processing_template_decl)
4232 val = build_address (arg);
4233 if (TREE_CODE (arg) == OFFSET_REF)
4234 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4238 /* If the user has taken the address of the compound literal,
4239 create a variable to contain the value of the literal and
4240 then return the address of that variable. */
4241 if (COMPOUND_LITERAL_P (arg))
4244 gcc_assert (TREE_STATIC (arg));
4245 var = create_temporary_var (TREE_TYPE (arg));
4246 TREE_STATIC (var) = 1;
4247 set_compound_literal_name (var);
4248 initialize_artificial_var (var, arg);
4249 arg = pushdecl (var);
4250 /* Since each compound literal is unique, pushdecl should
4251 never find a pre-existing variable with the same
4253 gcc_assert (arg == var);
4256 if (TREE_CODE (arg) != COMPONENT_REF)
4258 val = build_address (arg);
4259 if (TREE_CODE (arg) == OFFSET_REF)
4260 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4262 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4264 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4266 /* We can only get here with a single static member
4268 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4269 && DECL_STATIC_FUNCTION_P (fn));
4271 val = build_address (fn);
4272 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4273 /* Do not lose object's side effects. */
4274 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4275 TREE_OPERAND (arg, 0), val);
4277 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4279 error ("attempt to take address of bit-field structure member %qD",
4280 TREE_OPERAND (arg, 1));
4281 return error_mark_node;
4285 tree object = TREE_OPERAND (arg, 0);
4286 tree field = TREE_OPERAND (arg, 1);
4287 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4288 (TREE_TYPE (object), decl_type_context (field)));
4289 val = build_address (arg);
4292 if (TREE_CODE (argtype) == POINTER_TYPE
4293 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4295 build_ptrmemfunc_type (argtype);
4296 val = build_ptrmemfunc (argtype, val, 0,
4297 /*c_cast_p=*/false);
4309 argtype = TREE_TYPE (arg);
4310 return fold_if_not_in_template (build1 (code, argtype, arg));
4313 error ("%s", errstring);
4314 return error_mark_node;
4317 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4318 for certain kinds of expressions which are not really lvalues
4319 but which we can accept as lvalues.
4321 If ARG is not a kind of expression we can handle, return
4325 unary_complex_lvalue (enum tree_code code, tree arg)
4327 /* Inside a template, making these kinds of adjustments is
4328 pointless; we are only concerned with the type of the
4330 if (processing_template_decl)
4333 /* Handle (a, b) used as an "lvalue". */
4334 if (TREE_CODE (arg) == COMPOUND_EXPR)
4336 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4337 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4338 TREE_OPERAND (arg, 0), real_result);
4341 /* Handle (a ? b : c) used as an "lvalue". */
4342 if (TREE_CODE (arg) == COND_EXPR
4343 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4344 return rationalize_conditional_expr (code, arg);
4346 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4347 if (TREE_CODE (arg) == MODIFY_EXPR
4348 || TREE_CODE (arg) == PREINCREMENT_EXPR
4349 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4351 tree lvalue = TREE_OPERAND (arg, 0);
4352 if (TREE_SIDE_EFFECTS (lvalue))
4354 lvalue = stabilize_reference (lvalue);
4355 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4356 lvalue, TREE_OPERAND (arg, 1));
4358 return unary_complex_lvalue
4359 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4362 if (code != ADDR_EXPR)
4365 /* Handle (a = b) used as an "lvalue" for `&'. */
4366 if (TREE_CODE (arg) == MODIFY_EXPR
4367 || TREE_CODE (arg) == INIT_EXPR)
4369 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4370 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4372 TREE_NO_WARNING (arg) = 1;
4376 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4377 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4378 || TREE_CODE (arg) == OFFSET_REF)
4381 /* We permit compiler to make function calls returning
4382 objects of aggregate type look like lvalues. */
4386 if (TREE_CODE (targ) == SAVE_EXPR)
4387 targ = TREE_OPERAND (targ, 0);
4389 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4391 if (TREE_CODE (arg) == SAVE_EXPR)
4394 targ = build_cplus_new (TREE_TYPE (arg), arg);
4395 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4398 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4399 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4400 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4403 /* Don't let anything else be handled specially. */
4407 /* Mark EXP saying that we need to be able to take the
4408 address of it; it should not be allocated in a register.
4409 Value is true if successful.
4411 C++: we do not allow `current_class_ptr' to be addressable. */
4414 cxx_mark_addressable (tree exp)
4419 switch (TREE_CODE (x))
4426 x = TREE_OPERAND (x, 0);
4430 if (x == current_class_ptr)
4432 error ("cannot take the address of %<this%>, which is an rvalue expression");
4433 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4439 /* Caller should not be trying to mark initialized
4440 constant fields addressable. */
4441 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4442 || DECL_IN_AGGR_P (x) == 0
4444 || DECL_EXTERNAL (x));
4449 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4450 && !DECL_ARTIFICIAL (x))
4452 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4455 ("address of explicit register variable %qD requested", x);
4458 else if (extra_warnings)
4460 (0, "address requested for %qD, which is declared %<register%>", x);
4462 TREE_ADDRESSABLE (x) = 1;
4466 TREE_ADDRESSABLE (x) = 1;
4470 TREE_ADDRESSABLE (x) = 1;
4474 TREE_ADDRESSABLE (x) = 1;
4475 cxx_mark_addressable (TREE_OPERAND (x, 0));
4483 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4486 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4488 tree orig_ifexp = ifexp;
4489 tree orig_op1 = op1;
4490 tree orig_op2 = op2;
4493 if (processing_template_decl)
4495 /* The standard says that the expression is type-dependent if
4496 IFEXP is type-dependent, even though the eventual type of the
4497 expression doesn't dependent on IFEXP. */
4498 if (type_dependent_expression_p (ifexp)
4499 /* As a GNU extension, the middle operand may be omitted. */
4500 || (op1 && type_dependent_expression_p (op1))
4501 || type_dependent_expression_p (op2))
4502 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4503 ifexp = build_non_dependent_expr (ifexp);
4505 op1 = build_non_dependent_expr (op1);
4506 op2 = build_non_dependent_expr (op2);
4509 expr = build_conditional_expr (ifexp, op1, op2);
4510 if (processing_template_decl && expr != error_mark_node)
4511 return build_min_non_dep (COND_EXPR, expr,
4512 orig_ifexp, orig_op1, orig_op2);
4516 /* Given a list of expressions, return a compound expression
4517 that performs them all and returns the value of the last of them. */
4519 tree build_x_compound_expr_from_list (tree list, const char *msg)
4521 tree expr = TREE_VALUE (list);
4523 if (TREE_CHAIN (list))
4526 pedwarn ("%s expression list treated as compound expression", msg);
4528 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4529 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4535 /* Handle overloading of the ',' operator when needed. */
4538 build_x_compound_expr (tree op1, tree op2)
4541 tree orig_op1 = op1;
4542 tree orig_op2 = op2;
4544 if (processing_template_decl)
4546 if (type_dependent_expression_p (op1)
4547 || type_dependent_expression_p (op2))
4548 return build_min_nt (COMPOUND_EXPR, op1, op2);
4549 op1 = build_non_dependent_expr (op1);
4550 op2 = build_non_dependent_expr (op2);
4553 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4554 /*overloaded_p=*/NULL);
4556 result = build_compound_expr (op1, op2);
4558 if (processing_template_decl && result != error_mark_node)
4559 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4564 /* Build a compound expression. */
4567 build_compound_expr (tree lhs, tree rhs)
4569 lhs = convert_to_void (lhs, "left-hand operand of comma");
4571 if (lhs == error_mark_node || rhs == error_mark_node)
4572 return error_mark_node;
4574 if (TREE_CODE (rhs) == TARGET_EXPR)
4576 /* If the rhs is a TARGET_EXPR, then build the compound
4577 expression inside the target_expr's initializer. This
4578 helps the compiler to eliminate unnecessary temporaries. */
4579 tree init = TREE_OPERAND (rhs, 1);
4581 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4582 TREE_OPERAND (rhs, 1) = init;
4587 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4590 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
4591 casts away constness. DIAG_FN gives the function to call if we
4592 need to issue a diagnostic; if it is NULL, no diagnostic will be
4593 issued. DESCRIPTION explains what operation is taking place. */
4596 check_for_casting_away_constness (tree src_type, tree dest_type,
4597 void (*diag_fn)(const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2),
4598 const char *description)
4600 if (diag_fn && casts_away_constness (src_type, dest_type))
4601 diag_fn ("%s from type %qT to type %qT casts away constness",
4602 description, src_type, dest_type);
4605 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
4606 (another pointer-to-member type in the same hierarchy) and return
4607 the converted expression. If ALLOW_INVERSE_P is permitted, a
4608 pointer-to-derived may be converted to pointer-to-base; otherwise,
4609 only the other direction is permitted. If C_CAST_P is true, this
4610 conversion is taking place as part of a C-style cast. */
4613 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
4616 if (TYPE_PTRMEM_P (type))
4620 if (TREE_CODE (expr) == PTRMEM_CST)
4621 expr = cplus_expand_constant (expr);
4622 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
4623 TYPE_PTRMEM_CLASS_TYPE (type),
4626 if (!integer_zerop (delta))
4627 expr = cp_build_binary_op (PLUS_EXPR,
4628 build_nop (ptrdiff_type_node, expr),
4630 return build_nop (type, expr);
4633 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4634 allow_inverse_p, c_cast_p);
4637 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
4638 a version of EXPR that has TREE_OVERFLOW and/or TREE_CONSTANT_OVERFLOW
4639 set iff they are set in ORIG. Otherwise, return EXPR unchanged. */
4642 ignore_overflows (tree expr, tree orig)
4644 if (TREE_CODE (expr) == INTEGER_CST
4645 && CONSTANT_CLASS_P (orig)
4646 && TREE_CODE (orig) != STRING_CST
4647 && (TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig)
4648 || TREE_CONSTANT_OVERFLOW (expr)
4649 != TREE_CONSTANT_OVERFLOW (orig)))
4651 if (!TREE_OVERFLOW (orig) && !TREE_CONSTANT_OVERFLOW (orig))
4652 /* Ensure constant sharing. */
4653 expr = build_int_cst_wide (TREE_TYPE (expr),
4654 TREE_INT_CST_LOW (expr),
4655 TREE_INT_CST_HIGH (expr));
4658 /* Avoid clobbering a shared constant. */
4659 expr = copy_node (expr);
4660 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
4661 TREE_CONSTANT_OVERFLOW (expr)
4662 = TREE_CONSTANT_OVERFLOW (orig);
4668 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
4669 this static_cast is being attempted as one of the possible casts
4670 allowed by a C-style cast. (In that case, accessibility of base
4671 classes is not considered, and it is OK to cast away
4672 constness.) Return the result of the cast. *VALID_P is set to
4673 indicate whether or not the cast was valid. */
4676 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
4682 void (*diag_fn)(const char*, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
4685 /* Assume the cast is valid. */
4688 intype = TREE_TYPE (expr);
4690 /* Determine what to do when casting away constness. */
4693 /* C-style casts are allowed to cast away constness. With
4694 WARN_CAST_QUAL, we still want to issue a warning. */
4695 diag_fn = warn_cast_qual ? warning0 : NULL;
4700 /* A static_cast may not cast away constness. */
4702 desc = "static_cast";
4705 /* [expr.static.cast]
4707 An lvalue of type "cv1 B", where B is a class type, can be cast
4708 to type "reference to cv2 D", where D is a class derived (clause
4709 _class.derived_) from B, if a valid standard conversion from
4710 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4711 same cv-qualification as, or greater cv-qualification than, cv1,
4712 and B is not a virtual base class of D. */
4713 /* We check this case before checking the validity of "TYPE t =
4714 EXPR;" below because for this case:
4717 struct D : public B { D(const B&); };
4719 void f() { static_cast<const D&>(b); }
4721 we want to avoid constructing a new D. The standard is not
4722 completely clear about this issue, but our interpretation is
4723 consistent with other compilers. */
4724 if (TREE_CODE (type) == REFERENCE_TYPE
4725 && CLASS_TYPE_P (TREE_TYPE (type))
4726 && CLASS_TYPE_P (intype)
4727 && real_lvalue_p (expr)
4728 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4729 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4730 build_pointer_type (TYPE_MAIN_VARIANT
4731 (TREE_TYPE (type))))
4733 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
4737 /* There is a standard conversion from "D*" to "B*" even if "B"
4738 is ambiguous or inaccessible. If this is really a
4739 static_cast, then we check both for inaccessibility and
4740 ambiguity. However, if this is a static_cast being performed
4741 because the user wrote a C-style cast, then accessibility is
4743 base = lookup_base (TREE_TYPE (type), intype,
4744 c_cast_p ? ba_unique : ba_check,
4747 /* Convert from "B*" to "D*". This function will check that "B"
4748 is not a virtual base of "D". */
4749 expr = build_base_path (MINUS_EXPR, build_address (expr),
4750 base, /*nonnull=*/false);
4751 /* Convert the pointer to a reference -- but then remember that
4752 there are no expressions with reference type in C++. */
4753 return convert_from_reference (build_nop (type, expr));
4758 /* [expr.static.cast]
4760 An expression e can be explicitly converted to a type T using a
4761 static_cast of the form static_cast<T>(e) if the declaration T
4762 t(e);" is well-formed, for some invented temporary variable
4764 result = perform_direct_initialization_if_possible (type, expr,
4768 result = convert_from_reference (result);
4770 /* Ignore any integer overflow caused by the cast. */
4771 result = ignore_overflows (result, orig);
4773 /* [expr.static.cast]
4775 If T is a reference type, the result is an lvalue; otherwise,
4776 the result is an rvalue. */
4777 if (TREE_CODE (type) != REFERENCE_TYPE)
4778 result = rvalue (result);
4782 /* [expr.static.cast]
4784 Any expression can be explicitly converted to type cv void. */
4785 if (TREE_CODE (type) == VOID_TYPE)
4786 return convert_to_void (expr, /*implicit=*/NULL);
4788 /* [expr.static.cast]
4790 The inverse of any standard conversion sequence (clause _conv_),
4791 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4792 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4793 (_conv.bool_) conversions, can be performed explicitly using
4794 static_cast subject to the restriction that the explicit
4795 conversion does not cast away constness (_expr.const.cast_), and
4796 the following additional rules for specific cases: */
4797 /* For reference, the conversions not excluded are: integral
4798 promotions, floating point promotion, integral conversions,
4799 floating point conversions, floating-integral conversions,
4800 pointer conversions, and pointer to member conversions. */
4803 A value of integral _or enumeration_ type can be explicitly
4804 converted to an enumeration type. */
4805 /* The effect of all that is that any conversion between any two
4806 types which are integral, floating, or enumeration types can be
4808 if ((INTEGRAL_TYPE_P (type) || SCALAR_FLOAT_TYPE_P (type))
4809 && (INTEGRAL_TYPE_P (intype) || SCALAR_FLOAT_TYPE_P (intype)))
4811 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
4813 /* Ignore any integer overflow caused by the cast. */
4814 expr = ignore_overflows (expr, orig);
4818 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4819 && CLASS_TYPE_P (TREE_TYPE (type))
4820 && CLASS_TYPE_P (TREE_TYPE (intype))
4821 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4822 (TREE_TYPE (intype))),
4823 build_pointer_type (TYPE_MAIN_VARIANT
4824 (TREE_TYPE (type)))))
4829 check_for_casting_away_constness (intype, type, diag_fn, desc);
4830 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
4831 c_cast_p ? ba_unique : ba_check,
4833 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4836 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4837 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4844 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4845 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4847 if (TYPE_PTRMEM_P (type))
4849 t1 = (build_ptrmem_type
4851 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4852 t2 = (build_ptrmem_type
4854 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4861 if (can_convert (t1, t2))
4864 check_for_casting_away_constness (intype, type, diag_fn,
4866 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
4871 /* [expr.static.cast]
4873 An rvalue of type "pointer to cv void" can be explicitly
4874 converted to a pointer to object type. A value of type pointer
4875 to object converted to "pointer to cv void" and back to the
4876 original pointer type will have its original value. */
4877 if (TREE_CODE (intype) == POINTER_TYPE
4878 && VOID_TYPE_P (TREE_TYPE (intype))
4879 && TYPE_PTROB_P (type))
4882 check_for_casting_away_constness (intype, type, diag_fn, desc);
4883 return build_nop (type, expr);
4887 return error_mark_node;
4890 /* Return an expression representing static_cast<TYPE>(EXPR). */
4893 build_static_cast (tree type, tree expr)
4898 if (type == error_mark_node || expr == error_mark_node)
4899 return error_mark_node;
4901 if (processing_template_decl)
4903 expr = build_min (STATIC_CAST_EXPR, type, expr);
4904 /* We don't know if it will or will not have side effects. */
4905 TREE_SIDE_EFFECTS (expr) = 1;
4906 return convert_from_reference (expr);
4909 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4910 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4911 if (TREE_CODE (type) != REFERENCE_TYPE
4912 && TREE_CODE (expr) == NOP_EXPR
4913 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4914 expr = TREE_OPERAND (expr, 0);
4916 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p);
4920 error ("invalid static_cast from type %qT to type %qT",
4921 TREE_TYPE (expr), type);
4922 return error_mark_node;
4925 /* EXPR is an expression with member function or pointer-to-member
4926 function type. TYPE is a pointer type. Converting EXPR to TYPE is
4927 not permitted by ISO C++, but we accept it in some modes. If we
4928 are not in one of those modes, issue a diagnostic. Return the
4929 converted expression. */
4932 convert_member_func_to_ptr (tree type, tree expr)
4937 intype = TREE_TYPE (expr);
4938 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
4939 || TREE_CODE (intype) == METHOD_TYPE);
4941 if (pedantic || warn_pmf2ptr)
4942 pedwarn ("converting from %qT to %qT", intype, type);
4944 if (TREE_CODE (intype) == METHOD_TYPE)
4945 expr = build_addr_func (expr);
4946 else if (TREE_CODE (expr) == PTRMEM_CST)
4947 expr = build_address (PTRMEM_CST_MEMBER (expr));
4950 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
4951 decl = build_address (decl);
4952 expr = get_member_function_from_ptrfunc (&decl, expr);
4955 return build_nop (type, expr);
4958 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
4959 If C_CAST_P is true, this reinterpret cast is being done as part of
4960 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
4961 indicate whether or not reinterpret_cast was valid. */
4964 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
4969 /* Assume the cast is invalid. */
4973 if (type == error_mark_node || error_operand_p (expr))
4974 return error_mark_node;
4976 intype = TREE_TYPE (expr);
4978 /* [expr.reinterpret.cast]
4979 An lvalue expression of type T1 can be cast to the type
4980 "reference to T2" if an expression of type "pointer to T1" can be
4981 explicitly converted to the type "pointer to T2" using a
4982 reinterpret_cast. */
4983 if (TREE_CODE (type) == REFERENCE_TYPE)
4985 if (! real_lvalue_p (expr))
4987 error ("invalid cast of an rvalue expression of type "
4990 return error_mark_node;
4993 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
4994 "B" are related class types; the reinterpret_cast does not
4995 adjust the pointer. */
4996 if (TYPE_PTR_P (intype)
4997 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
4998 COMPARE_BASE | COMPARE_DERIVED)))
4999 warning (0, "casting %qT to %qT does not dereference pointer",
5002 expr = build_unary_op (ADDR_EXPR, expr, 0);
5003 if (expr != error_mark_node)
5004 expr = build_reinterpret_cast_1
5005 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5007 if (expr != error_mark_node)
5008 expr = build_indirect_ref (expr, 0);
5012 /* As a G++ extension, we consider conversions from member
5013 functions, and pointers to member functions to
5014 pointer-to-function and pointer-to-void types. If
5015 -Wno-pmf-conversions has not been specified,
5016 convert_member_func_to_ptr will issue an error message. */
5017 if ((TYPE_PTRMEMFUNC_P (intype)
5018 || TREE_CODE (intype) == METHOD_TYPE)
5019 && TYPE_PTR_P (type)
5020 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5021 || VOID_TYPE_P (TREE_TYPE (type))))
5022 return convert_member_func_to_ptr (type, expr);
5024 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5025 array-to-pointer, and function-to-pointer conversions are
5027 expr = decay_conversion (expr);
5029 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5030 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5031 if (TREE_CODE (expr) == NOP_EXPR
5032 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5033 expr = TREE_OPERAND (expr, 0);
5035 if (error_operand_p (expr))
5036 return error_mark_node;
5038 intype = TREE_TYPE (expr);
5040 /* [expr.reinterpret.cast]
5041 A pointer can be converted to any integral type large enough to
5043 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5045 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5046 pedwarn ("cast from %qT to %qT loses precision",
5049 /* [expr.reinterpret.cast]
5050 A value of integral or enumeration type can be explicitly
5051 converted to a pointer. */
5052 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5055 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5056 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5057 return fold_if_not_in_template (build_nop (type, expr));
5058 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5059 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5064 check_for_casting_away_constness (intype, type, error,
5065 "reinterpret_cast");
5066 /* Warn about possible alignment problems. */
5067 if (STRICT_ALIGNMENT && warn_cast_align
5068 && !VOID_TYPE_P (type)
5069 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5070 && COMPLETE_TYPE_P (TREE_TYPE (type))
5071 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5072 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5073 warning (0, "cast from %qT to %qT increases required alignment of "
5077 /* We need to strip nops here, because the frontend likes to
5078 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5080 strict_aliasing_warning (intype, type, sexpr);
5082 return fold_if_not_in_template (build_nop (type, expr));
5084 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5085 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5088 /* Only issue a warning, as we have always supported this
5089 where possible, and it is necessary in some cases. DR 195
5090 addresses this issue, but as of 2004/10/26 is still in
5092 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5093 return fold_if_not_in_template (build_nop (type, expr));
5095 else if (TREE_CODE (type) == VECTOR_TYPE)
5096 return fold_if_not_in_template (convert_to_vector (type, expr));
5097 else if (TREE_CODE (intype) == VECTOR_TYPE)
5098 return fold_if_not_in_template (convert_to_integer (type, expr));
5103 error ("invalid cast from type %qT to type %qT", intype, type);
5104 return error_mark_node;
5107 return cp_convert (type, expr);
5111 build_reinterpret_cast (tree type, tree expr)
5113 if (type == error_mark_node || expr == error_mark_node)
5114 return error_mark_node;
5116 if (processing_template_decl)
5118 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5120 if (!TREE_SIDE_EFFECTS (t)
5121 && type_dependent_expression_p (expr))
5122 /* There might turn out to be side effects inside expr. */
5123 TREE_SIDE_EFFECTS (t) = 1;
5124 return convert_from_reference (t);
5127 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5131 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5132 return an appropriate expression. Otherwise, return
5133 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5134 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5135 performing a C-style cast, its value upon return will indicate
5136 whether or not the conversion succeeded. */
5139 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5143 tree reference_type;
5145 /* Callers are responsible for handling error_mark_node as a
5146 destination type. */
5147 gcc_assert (dst_type != error_mark_node);
5148 /* In a template, callers should be building syntactic
5149 representations of casts, not using this machinery. */
5150 gcc_assert (!processing_template_decl);
5152 /* Assume the conversion is invalid. */
5156 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5159 error ("invalid use of const_cast with type %qT, "
5160 "which is not a pointer, "
5161 "reference, nor a pointer-to-data-member type", dst_type);
5162 return error_mark_node;
5165 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5168 error ("invalid use of const_cast with type %qT, which is a pointer "
5169 "or reference to a function type", dst_type);
5170 return error_mark_node;
5173 src_type = TREE_TYPE (expr);
5174 /* Expressions do not really have reference types. */
5175 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5176 src_type = TREE_TYPE (src_type);
5178 /* [expr.const.cast]
5180 An lvalue of type T1 can be explicitly converted to an lvalue of
5181 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5182 types) if a pointer to T1 can be explicitly converted to the type
5183 pointer to T2 using a const_cast. */
5184 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5186 reference_type = dst_type;
5187 if (! real_lvalue_p (expr))
5190 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5191 src_type, dst_type);
5192 return error_mark_node;
5194 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5195 src_type = build_pointer_type (src_type);
5199 reference_type = NULL_TREE;
5200 /* If the destination type is not a reference type, the
5201 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5202 conversions are performed. */
5203 src_type = type_decays_to (src_type);
5204 if (src_type == error_mark_node)
5205 return error_mark_node;
5208 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5209 && comp_ptr_ttypes_const (dst_type, src_type))
5214 /* This cast is actually a C-style cast. Issue a warning if
5215 the user is making a potentially unsafe cast. */
5217 check_for_casting_away_constness (src_type, dst_type,
5223 expr = build_unary_op (ADDR_EXPR, expr, 0);
5224 expr = build_nop (reference_type, expr);
5225 return convert_from_reference (expr);
5229 expr = decay_conversion (expr);
5230 /* build_c_cast puts on a NOP_EXPR to make the result not an
5231 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5232 non-lvalue context. */
5233 if (TREE_CODE (expr) == NOP_EXPR
5234 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5235 expr = TREE_OPERAND (expr, 0);
5236 return build_nop (dst_type, expr);
5241 error ("invalid const_cast from type %qT to type %qT",
5242 src_type, dst_type);
5243 return error_mark_node;
5247 build_const_cast (tree type, tree expr)
5249 if (type == error_mark_node || error_operand_p (expr))
5250 return error_mark_node;
5252 if (processing_template_decl)
5254 tree t = build_min (CONST_CAST_EXPR, type, expr);
5256 if (!TREE_SIDE_EFFECTS (t)
5257 && type_dependent_expression_p (expr))
5258 /* There might turn out to be side effects inside expr. */
5259 TREE_SIDE_EFFECTS (t) = 1;
5260 return convert_from_reference (t);
5263 return build_const_cast_1 (type, expr, /*complain=*/true,
5267 /* Build an expression representing an explicit C-style cast to type
5268 TYPE of expression EXPR. */
5271 build_c_cast (tree type, tree expr)
5277 if (type == error_mark_node || error_operand_p (expr))
5278 return error_mark_node;
5280 if (processing_template_decl)
5282 tree t = build_min (CAST_EXPR, type,
5283 tree_cons (NULL_TREE, value, NULL_TREE));
5284 /* We don't know if it will or will not have side effects. */
5285 TREE_SIDE_EFFECTS (t) = 1;
5286 return convert_from_reference (t);
5289 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5290 'Class') should always be retained, because this information aids
5291 in method lookup. */
5292 if (objc_is_object_ptr (type)
5293 && objc_is_object_ptr (TREE_TYPE (expr)))
5294 return build_nop (type, expr);
5296 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5297 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5298 if (TREE_CODE (type) != REFERENCE_TYPE
5299 && TREE_CODE (value) == NOP_EXPR
5300 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5301 value = TREE_OPERAND (value, 0);
5303 if (TREE_CODE (type) == ARRAY_TYPE)
5305 /* Allow casting from T1* to T2[] because Cfront allows it.
5306 NIHCL uses it. It is not valid ISO C++ however. */
5307 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5309 pedwarn ("ISO C++ forbids casting to an array type %qT", type);
5310 type = build_pointer_type (TREE_TYPE (type));
5314 error ("ISO C++ forbids casting to an array type %qT", type);
5315 return error_mark_node;
5319 if (TREE_CODE (type) == FUNCTION_TYPE
5320 || TREE_CODE (type) == METHOD_TYPE)
5322 error ("invalid cast to function type %qT", type);
5323 return error_mark_node;
5326 /* A C-style cast can be a const_cast. */
5327 result = build_const_cast_1 (type, value, /*complain=*/false,
5332 /* Or a static cast. */
5333 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5335 /* Or a reinterpret_cast. */
5337 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5339 /* The static_cast or reinterpret_cast may be followed by a
5342 /* A valid cast may result in errors if, for example, a
5343 conversion to am ambiguous base class is required. */
5344 && !error_operand_p (result))
5348 /* Non-class rvalues always have cv-unqualified type. */
5349 if (!CLASS_TYPE_P (type))
5350 type = TYPE_MAIN_VARIANT (type);
5351 result_type = TREE_TYPE (result);
5352 if (!CLASS_TYPE_P (result_type))
5353 result_type = TYPE_MAIN_VARIANT (result_type);
5354 /* If the type of RESULT does not match TYPE, perform a
5355 const_cast to make it match. If the static_cast or
5356 reinterpret_cast succeeded, we will differ by at most
5357 cv-qualification, so the follow-on const_cast is guaranteed
5359 if (!same_type_p (non_reference (type), non_reference (result_type)))
5361 result = build_const_cast_1 (type, result, false, &valid_p);
5362 gcc_assert (valid_p);
5367 return error_mark_node;
5370 /* Build an assignment expression of lvalue LHS from value RHS.
5371 MODIFYCODE is the code for a binary operator that we use
5372 to combine the old value of LHS with RHS to get the new value.
5373 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5375 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5378 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5382 tree lhstype = TREE_TYPE (lhs);
5383 tree olhstype = lhstype;
5384 tree olhs = NULL_TREE;
5385 bool plain_assign = (modifycode == NOP_EXPR);
5387 /* Avoid duplicate error messages from operands that had errors. */
5388 if (error_operand_p (lhs) || error_operand_p (rhs))
5389 return error_mark_node;
5391 /* Handle control structure constructs used as "lvalues". */
5392 switch (TREE_CODE (lhs))
5394 /* Handle --foo = 5; as these are valid constructs in C++. */
5395 case PREDECREMENT_EXPR:
5396 case PREINCREMENT_EXPR:
5397 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5398 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5399 stabilize_reference (TREE_OPERAND (lhs, 0)),
5400 TREE_OPERAND (lhs, 1));
5401 return build2 (COMPOUND_EXPR, lhstype,
5403 build_modify_expr (TREE_OPERAND (lhs, 0),
5406 /* Handle (a, b) used as an "lvalue". */
5408 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
5410 if (newrhs == error_mark_node)
5411 return error_mark_node;
5412 return build2 (COMPOUND_EXPR, lhstype,
5413 TREE_OPERAND (lhs, 0), newrhs);
5416 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5417 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5418 stabilize_reference (TREE_OPERAND (lhs, 0)),
5419 TREE_OPERAND (lhs, 1));
5420 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
5421 if (newrhs == error_mark_node)
5422 return error_mark_node;
5423 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5427 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
5428 when neither operand has side-effects. */
5429 if (!lvalue_or_else (lhs, lv_assign))
5430 return error_mark_node;
5432 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
5433 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
5435 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
5436 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
5438 TREE_OPERAND (lhs, 0),
5439 TREE_OPERAND (lhs, 1)),
5440 TREE_OPERAND (lhs, 0),
5441 TREE_OPERAND (lhs, 1));
5444 /* Handle (a ? b : c) used as an "lvalue". */
5447 /* Produce (a ? (b = rhs) : (c = rhs))
5448 except that the RHS goes through a save-expr
5449 so the code to compute it is only emitted once. */
5451 tree preeval = NULL_TREE;
5453 rhs = stabilize_expr (rhs, &preeval);
5455 /* Check this here to avoid odd errors when trying to convert
5456 a throw to the type of the COND_EXPR. */
5457 if (!lvalue_or_else (lhs, lv_assign))
5458 return error_mark_node;
5460 cond = build_conditional_expr
5461 (TREE_OPERAND (lhs, 0),
5462 build_modify_expr (cp_convert (TREE_TYPE (lhs),
5463 TREE_OPERAND (lhs, 1)),
5465 build_modify_expr (cp_convert (TREE_TYPE (lhs),
5466 TREE_OPERAND (lhs, 2)),
5469 if (cond == error_mark_node)
5471 /* Make sure the code to compute the rhs comes out
5472 before the split. */
5474 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5482 if (modifycode == INIT_EXPR)
5484 if (TREE_CODE (rhs) == CONSTRUCTOR)
5486 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5487 /* Call convert to generate an error; see PR 11063. */
5488 rhs = convert (lhstype, rhs);
5489 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
5490 TREE_SIDE_EFFECTS (result) = 1;
5493 else if (! IS_AGGR_TYPE (lhstype))
5494 /* Do the default thing. */;
5497 result = build_special_member_call (lhs, complete_ctor_identifier,
5498 build_tree_list (NULL_TREE, rhs),
5499 lhstype, LOOKUP_NORMAL);
5500 if (result == NULL_TREE)
5501 return error_mark_node;
5507 lhs = require_complete_type (lhs);
5508 if (lhs == error_mark_node)
5509 return error_mark_node;
5511 if (modifycode == NOP_EXPR)
5513 /* `operator=' is not an inheritable operator. */
5514 if (! IS_AGGR_TYPE (lhstype))
5515 /* Do the default thing. */;
5518 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5519 lhs, rhs, make_node (NOP_EXPR),
5520 /*overloaded_p=*/NULL);
5521 if (result == NULL_TREE)
5522 return error_mark_node;
5529 /* A binary op has been requested. Combine the old LHS
5530 value with the RHS producing the value we should actually
5531 store into the LHS. */
5533 gcc_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE));
5534 lhs = stabilize_reference (lhs);
5535 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
5536 if (newrhs == error_mark_node)
5538 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
5539 TREE_TYPE (lhs), TREE_TYPE (rhs));
5540 return error_mark_node;
5543 /* Now it looks like a plain assignment. */
5544 modifycode = NOP_EXPR;
5546 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
5547 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
5550 /* The left-hand side must be an lvalue. */
5551 if (!lvalue_or_else (lhs, lv_assign))
5552 return error_mark_node;
5554 /* Warn about modifying something that is `const'. Don't warn if
5555 this is initialization. */
5556 if (modifycode != INIT_EXPR
5557 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5558 /* Functions are not modifiable, even though they are
5560 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5561 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5562 /* If it's an aggregate and any field is const, then it is
5563 effectively const. */
5564 || (CLASS_TYPE_P (lhstype)
5565 && C_TYPE_FIELDS_READONLY (lhstype))))
5566 readonly_error (lhs, "assignment", 0);
5568 /* If storing into a structure or union member, it has probably been
5569 given type `int'. Compute the type that would go with the actual
5570 amount of storage the member occupies. */
5572 if (TREE_CODE (lhs) == COMPONENT_REF
5573 && (TREE_CODE (lhstype) == INTEGER_TYPE
5574 || TREE_CODE (lhstype) == REAL_TYPE
5575 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5577 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5579 /* If storing in a field that is in actuality a short or narrower
5580 than one, we must store in the field in its actual type. */
5582 if (lhstype != TREE_TYPE (lhs))
5584 /* Avoid warnings converting integral types back into enums for
5586 if (TREE_CODE (lhstype) == INTEGER_TYPE
5587 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5589 if (TREE_SIDE_EFFECTS (lhs))
5590 lhs = stabilize_reference (lhs);
5593 lhs = copy_node (lhs);
5594 TREE_TYPE (lhs) = lhstype;
5598 /* Convert new value to destination type. */
5600 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5604 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5605 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5607 error ("incompatible types in assignment of %qT to %qT",
5608 TREE_TYPE (rhs), lhstype);
5609 return error_mark_node;
5612 /* Allow array assignment in compiler-generated code. */
5613 if (! DECL_ARTIFICIAL (current_function_decl))
5614 pedwarn ("ISO C++ forbids assignment of arrays");
5616 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5617 ? 1 + (modifycode != INIT_EXPR): 0;
5618 return build_vec_init (lhs, NULL_TREE, newrhs,
5619 /*explicit_default_init_p=*/false,
5623 if (modifycode == INIT_EXPR)
5624 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5625 "initialization", NULL_TREE, 0);
5628 /* Avoid warnings on enum bit fields. */
5629 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5630 && TREE_CODE (lhstype) == INTEGER_TYPE)
5632 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5634 newrhs = convert_force (lhstype, newrhs, 0);
5637 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5639 if (TREE_CODE (newrhs) == CALL_EXPR
5640 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5641 newrhs = build_cplus_new (lhstype, newrhs);
5643 /* Can't initialize directly from a TARGET_EXPR, since that would
5644 cause the lhs to be constructed twice, and possibly result in
5645 accidental self-initialization. So we force the TARGET_EXPR to be
5646 expanded without a target. */
5647 if (TREE_CODE (newrhs) == TARGET_EXPR)
5648 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5649 TREE_OPERAND (newrhs, 0));
5652 if (newrhs == error_mark_node)
5653 return error_mark_node;
5655 if (TREE_CODE (lhs) == COMPONENT_REF)
5656 newrhs = adjust_bitfield_initializer (TREE_OPERAND (lhs, 1),
5659 if (c_dialect_objc () && flag_objc_gc)
5661 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
5667 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5668 lhstype, lhs, newrhs);
5670 TREE_SIDE_EFFECTS (result) = 1;
5672 TREE_NO_WARNING (result) = 1;
5674 /* If we got the LHS in a different type for storing in,
5675 convert the result back to the nominal type of LHS
5676 so that the value we return always has the same type
5677 as the LHS argument. */
5679 if (olhstype == TREE_TYPE (result))
5683 result = build2 (COMPOUND_EXPR, olhstype, result, olhs);
5684 TREE_NO_WARNING (result) = 1;
5687 return convert_for_assignment (olhstype, result, "assignment",
5692 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5694 if (processing_template_decl)
5695 return build_min_nt (MODOP_EXPR, lhs,
5696 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5698 if (modifycode != NOP_EXPR)
5700 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5701 make_node (modifycode),
5702 /*overloaded_p=*/NULL);
5705 TREE_NO_WARNING (rval) = 1;
5709 return build_modify_expr (lhs, modifycode, rhs);
5713 /* Get difference in deltas for different pointer to member function
5714 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5715 the conversion is invalid, the constant is zero. If
5716 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
5717 If C_CAST_P is true this conversion is taking place as part of a
5720 Note that the naming of FROM and TO is kind of backwards; the return
5721 value is what we add to a TO in order to get a FROM. They are named
5722 this way because we call this function to find out how to convert from
5723 a pointer to member of FROM to a pointer to member of TO. */
5726 get_delta_difference (tree from, tree to,
5727 bool allow_inverse_p,
5734 /* Assume no conversion is required. */
5735 result = integer_zero_node;
5736 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
5737 if (kind == bk_inaccessible || kind == bk_ambig)
5738 error (" in pointer to member function conversion");
5741 if (kind != bk_via_virtual)
5742 result = BINFO_OFFSET (binfo);
5745 tree virt_binfo = binfo_from_vbase (binfo);
5747 /* This is a reinterpret cast, we choose to do nothing. */
5748 if (allow_inverse_p)
5749 warning (0, "pointer to member cast via virtual base %qT",
5750 BINFO_TYPE (virt_binfo));
5752 error ("pointer to member conversion via virtual base %qT",
5753 BINFO_TYPE (virt_binfo));
5756 else if (same_type_ignoring_top_level_qualifiers_p (from, to))
5757 /* Pointer to member of incomplete class is permitted*/;
5758 else if (!allow_inverse_p)
5760 error_not_base_type (from, to);
5761 error (" in pointer to member conversion");
5765 binfo = lookup_base (from, to, c_cast_p ? ba_unique : ba_check, &kind);
5768 if (kind != bk_via_virtual)
5769 result = size_diffop (size_zero_node, BINFO_OFFSET (binfo));
5772 /* This is a reinterpret cast, we choose to do nothing. */
5773 tree virt_binfo = binfo_from_vbase (binfo);
5775 warning (0, "pointer to member cast via virtual base %qT",
5776 BINFO_TYPE (virt_binfo));
5781 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
5785 /* Return a constructor for the pointer-to-member-function TYPE using
5786 the other components as specified. */
5789 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5794 VEC(constructor_elt, gc) *v;
5796 /* Pull the FIELD_DECLs out of the type. */
5797 pfn_field = TYPE_FIELDS (type);
5798 delta_field = TREE_CHAIN (pfn_field);
5800 /* Make sure DELTA has the type we want. */
5801 delta = convert_and_check (delta_type_node, delta);
5803 /* Finish creating the initializer. */
5804 v = VEC_alloc(constructor_elt, gc, 2);
5805 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
5806 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
5807 u = build_constructor (type, v);
5808 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
5809 TREE_INVARIANT (u) = TREE_INVARIANT (pfn) & TREE_INVARIANT (delta);
5810 TREE_STATIC (u) = (TREE_CONSTANT (u)
5811 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5813 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5818 /* Build a constructor for a pointer to member function. It can be
5819 used to initialize global variables, local variable, or used
5820 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5823 If FORCE is nonzero, then force this conversion, even if
5824 we would rather not do it. Usually set when using an explicit
5825 cast. A C-style cast is being processed iff C_CAST_P is true.
5827 Return error_mark_node, if something goes wrong. */
5830 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
5836 if (error_operand_p (pfn))
5837 return error_mark_node;
5839 pfn_type = TREE_TYPE (pfn);
5840 to_type = build_ptrmemfunc_type (type);
5842 /* Handle multiple conversions of pointer to member functions. */
5843 if (TYPE_PTRMEMFUNC_P (pfn_type))
5845 tree delta = NULL_TREE;
5846 tree npfn = NULL_TREE;
5850 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
5851 error ("invalid conversion to type %qT from type %qT",
5854 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5855 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5859 /* We don't have to do any conversion to convert a
5860 pointer-to-member to its own type. But, we don't want to
5861 just return a PTRMEM_CST if there's an explicit cast; that
5862 cast should make the expression an invalid template argument. */
5863 if (TREE_CODE (pfn) != PTRMEM_CST)
5865 if (same_type_p (to_type, pfn_type))
5867 else if (integer_zerop (n))
5868 return build_reinterpret_cast (to_type, pfn);
5871 if (TREE_SIDE_EFFECTS (pfn))
5872 pfn = save_expr (pfn);
5874 /* Obtain the function pointer and the current DELTA. */
5875 if (TREE_CODE (pfn) == PTRMEM_CST)
5876 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
5879 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
5880 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
5883 /* Just adjust the DELTA field. */
5884 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5885 (TREE_TYPE (delta), ptrdiff_type_node));
5886 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
5887 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
5888 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
5889 return build_ptrmemfunc1 (to_type, delta, npfn);
5892 /* Handle null pointer to member function conversions. */
5893 if (integer_zerop (pfn))
5895 pfn = build_c_cast (type, integer_zero_node);
5896 return build_ptrmemfunc1 (to_type,
5901 if (type_unknown_p (pfn))
5902 return instantiate_type (type, pfn, tf_error | tf_warning);
5904 fn = TREE_OPERAND (pfn, 0);
5905 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
5906 /* In a template, we will have preserved the
5908 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
5909 return make_ptrmem_cst (to_type, fn);
5912 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
5915 ??? There is no consistency as to the types returned for the above
5916 values. Some code acts as if it were a sizetype and some as if it were
5917 integer_type_node. */
5920 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
5922 tree type = TREE_TYPE (cst);
5923 tree fn = PTRMEM_CST_MEMBER (cst);
5924 tree ptr_class, fn_class;
5926 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
5928 /* The class that the function belongs to. */
5929 fn_class = DECL_CONTEXT (fn);
5931 /* The class that we're creating a pointer to member of. */
5932 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
5934 /* First, calculate the adjustment to the function's class. */
5935 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
5938 if (!DECL_VIRTUAL_P (fn))
5939 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
5942 /* If we're dealing with a virtual function, we have to adjust 'this'
5943 again, to point to the base which provides the vtable entry for
5944 fn; the call will do the opposite adjustment. */
5945 tree orig_class = DECL_CONTEXT (fn);
5946 tree binfo = binfo_or_else (orig_class, fn_class);
5947 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
5948 *delta, BINFO_OFFSET (binfo));
5949 *delta = fold_if_not_in_template (*delta);
5951 /* We set PFN to the vtable offset at which the function can be
5952 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
5953 case delta is shifted left, and then incremented). */
5954 *pfn = DECL_VINDEX (fn);
5955 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
5956 TYPE_SIZE_UNIT (vtable_entry_type));
5957 *pfn = fold_if_not_in_template (*pfn);
5959 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
5961 case ptrmemfunc_vbit_in_pfn:
5962 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
5964 *pfn = fold_if_not_in_template (*pfn);
5967 case ptrmemfunc_vbit_in_delta:
5968 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
5969 *delta, integer_one_node);
5970 *delta = fold_if_not_in_template (*delta);
5971 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
5972 *delta, integer_one_node);
5973 *delta = fold_if_not_in_template (*delta);
5980 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
5981 *pfn = fold_if_not_in_template (*pfn);
5985 /* Return an expression for PFN from the pointer-to-member function
5989 pfn_from_ptrmemfunc (tree t)
5991 if (TREE_CODE (t) == PTRMEM_CST)
5996 expand_ptrmemfunc_cst (t, &delta, &pfn);
6001 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6004 /* Convert value RHS to type TYPE as preparation for an assignment to
6005 an lvalue of type TYPE. ERRTYPE is a string to use in error
6006 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6007 are doing the conversion in order to pass the PARMNUMth argument of
6011 convert_for_assignment (tree type, tree rhs,
6012 const char *errtype, tree fndecl, int parmnum)
6015 enum tree_code coder;
6017 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6018 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6019 rhs = TREE_OPERAND (rhs, 0);
6021 rhstype = TREE_TYPE (rhs);
6022 coder = TREE_CODE (rhstype);
6024 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6025 && vector_types_convertible_p (type, rhstype))
6026 return convert (type, rhs);
6028 if (rhs == error_mark_node || rhstype == error_mark_node)
6029 return error_mark_node;
6030 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6031 return error_mark_node;
6033 /* The RHS of an assignment cannot have void type. */
6034 if (coder == VOID_TYPE)
6036 error ("void value not ignored as it ought to be");
6037 return error_mark_node;
6040 /* Simplify the RHS if possible. */
6041 if (TREE_CODE (rhs) == CONST_DECL)
6042 rhs = DECL_INITIAL (rhs);
6044 if (c_dialect_objc ())
6047 tree rname = fndecl;
6049 if (!strcmp (errtype, "assignment"))
6051 else if (!strcmp (errtype, "initialization"))
6055 tree selector = objc_message_selector ();
6059 if (selector && parmno > 1)
6066 if (objc_compare_types (type, rhstype, parmno, rname))
6067 return convert (type, rhs);
6072 The expression is implicitly converted (clause _conv_) to the
6073 cv-unqualified type of the left operand.
6075 We allow bad conversions here because by the time we get to this point
6076 we are committed to doing the conversion. If we end up doing a bad
6077 conversion, convert_like will complain. */
6078 if (!can_convert_arg_bad (type, rhstype, rhs))
6080 /* When -Wno-pmf-conversions is use, we just silently allow
6081 conversions from pointers-to-members to plain pointers. If
6082 the conversion doesn't work, cp_convert will complain. */
6084 && TYPE_PTR_P (type)
6085 && TYPE_PTRMEMFUNC_P (rhstype))
6086 rhs = cp_convert (strip_top_quals (type), rhs);
6089 /* If the right-hand side has unknown type, then it is an
6090 overloaded function. Call instantiate_type to get error
6092 if (rhstype == unknown_type_node)
6093 instantiate_type (type, rhs, tf_error | tf_warning);
6095 error ("cannot convert %qT to %qT for argument %qP to %qD",
6096 rhstype, type, parmnum, fndecl);
6098 error ("cannot convert %qT to %qT in %s", rhstype, type, errtype);
6099 return error_mark_node;
6102 if (warn_missing_format_attribute)
6104 const enum tree_code codel = TREE_CODE (type);
6105 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6107 && check_missing_format_attribute (type, rhstype))
6108 warning (OPT_Wmissing_format_attribute,
6109 "%s might be a candidate for a format attribute",
6113 return perform_implicit_conversion (strip_top_quals (type), rhs);
6116 /* Convert RHS to be of type TYPE.
6117 If EXP is nonzero, it is the target of the initialization.
6118 ERRTYPE is a string to use in error messages.
6120 Two major differences between the behavior of
6121 `convert_for_assignment' and `convert_for_initialization'
6122 are that references are bashed in the former, while
6123 copied in the latter, and aggregates are assigned in
6124 the former (operator=) while initialized in the
6127 If using constructor make sure no conversion operator exists, if one does
6128 exist, an ambiguity exists.
6130 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6133 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6134 const char *errtype, tree fndecl, int parmnum)
6136 enum tree_code codel = TREE_CODE (type);
6138 enum tree_code coder;
6140 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6141 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6142 if (TREE_CODE (rhs) == NOP_EXPR
6143 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6144 && codel != REFERENCE_TYPE)
6145 rhs = TREE_OPERAND (rhs, 0);
6147 if (rhs == error_mark_node
6148 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6149 return error_mark_node;
6151 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6152 && TREE_CODE (type) != ARRAY_TYPE
6153 && (TREE_CODE (type) != REFERENCE_TYPE
6154 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6155 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6156 && (TREE_CODE (type) != REFERENCE_TYPE
6157 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6158 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6159 rhs = decay_conversion (rhs);
6161 rhstype = TREE_TYPE (rhs);
6162 coder = TREE_CODE (rhstype);
6164 if (coder == ERROR_MARK)
6165 return error_mark_node;
6167 /* We accept references to incomplete types, so we can
6168 return here before checking if RHS is of complete type. */
6170 if (codel == REFERENCE_TYPE)
6172 /* This should eventually happen in convert_arguments. */
6173 int savew = 0, savee = 0;
6176 savew = warningcount, savee = errorcount;
6177 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6181 if (warningcount > savew)
6182 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6183 else if (errorcount > savee)
6184 error ("in passing argument %P of %q+D", parmnum, fndecl);
6190 exp = require_complete_type (exp);
6191 if (exp == error_mark_node)
6192 return error_mark_node;
6194 rhstype = non_reference (rhstype);
6196 type = complete_type (type);
6198 if (IS_AGGR_TYPE (type))
6199 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6201 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
6204 /* If RETVAL is the address of, or a reference to, a local variable or
6205 temporary give an appropriate warning. */
6208 maybe_warn_about_returning_address_of_local (tree retval)
6210 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6211 tree whats_returned = retval;
6215 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6216 whats_returned = TREE_OPERAND (whats_returned, 1);
6217 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
6218 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
6219 || TREE_CODE (whats_returned) == NOP_EXPR)
6220 whats_returned = TREE_OPERAND (whats_returned, 0);
6225 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6227 whats_returned = TREE_OPERAND (whats_returned, 0);
6229 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6231 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6232 || TREE_CODE (whats_returned) == TARGET_EXPR)
6234 warning (0, "returning reference to temporary");
6237 if (TREE_CODE (whats_returned) == VAR_DECL
6238 && DECL_NAME (whats_returned)
6239 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6241 warning (0, "reference to non-lvalue returned");
6246 while (TREE_CODE (whats_returned) == COMPONENT_REF
6247 || TREE_CODE (whats_returned) == ARRAY_REF)
6248 whats_returned = TREE_OPERAND (whats_returned, 0);
6250 if (DECL_P (whats_returned)
6251 && DECL_NAME (whats_returned)
6252 && DECL_FUNCTION_SCOPE_P (whats_returned)
6253 && !(TREE_STATIC (whats_returned)
6254 || TREE_PUBLIC (whats_returned)))
6256 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6257 warning (0, "reference to local variable %q+D returned",
6260 warning (0, "address of local variable %q+D returned",
6266 /* Check that returning RETVAL from the current function is valid.
6267 Return an expression explicitly showing all conversions required to
6268 change RETVAL into the function return type, and to assign it to
6269 the DECL_RESULT for the function. Set *NO_WARNING to true if
6270 code reaches end of non-void function warning shouldn't be issued
6271 on this RETURN_EXPR. */
6274 check_return_expr (tree retval, bool *no_warning)
6277 /* The type actually returned by the function, after any
6280 int fn_returns_value_p;
6282 *no_warning = false;
6284 /* A `volatile' function is one that isn't supposed to return, ever.
6285 (This is a G++ extension, used to get better code for functions
6286 that call the `volatile' function.) */
6287 if (TREE_THIS_VOLATILE (current_function_decl))
6288 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6290 /* Check for various simple errors. */
6291 if (DECL_DESTRUCTOR_P (current_function_decl))
6294 error ("returning a value from a destructor");
6297 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6299 if (in_function_try_handler)
6300 /* If a return statement appears in a handler of the
6301 function-try-block of a constructor, the program is ill-formed. */
6302 error ("cannot return from a handler of a function-try-block of a constructor");
6304 /* You can't return a value from a constructor. */
6305 error ("returning a value from a constructor");
6309 if (processing_template_decl)
6311 current_function_returns_value = 1;
6315 /* When no explicit return-value is given in a function with a named
6316 return value, the named return value is used. */
6317 result = DECL_RESULT (current_function_decl);
6318 valtype = TREE_TYPE (result);
6319 gcc_assert (valtype != NULL_TREE);
6320 fn_returns_value_p = !VOID_TYPE_P (valtype);
6321 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6324 /* Check for a return statement with no return value in a function
6325 that's supposed to return a value. */
6326 if (!retval && fn_returns_value_p)
6328 pedwarn ("return-statement with no value, in function returning %qT",
6330 /* Clear this, so finish_function won't say that we reach the
6331 end of a non-void function (which we don't, we gave a
6333 current_function_returns_null = 0;
6334 /* And signal caller that TREE_NO_WARNING should be set on the
6335 RETURN_EXPR to avoid control reaches end of non-void function
6336 warnings in tree-cfg.c. */
6339 /* Check for a return statement with a value in a function that
6340 isn't supposed to return a value. */
6341 else if (retval && !fn_returns_value_p)
6343 if (VOID_TYPE_P (TREE_TYPE (retval)))
6344 /* You can return a `void' value from a function of `void'
6345 type. In that case, we have to evaluate the expression for
6346 its side-effects. */
6347 finish_expr_stmt (retval);
6349 pedwarn ("return-statement with a value, in function "
6350 "returning 'void'");
6352 current_function_returns_null = 1;
6354 /* There's really no value to return, after all. */
6358 /* Remember that this function can sometimes return without a
6360 current_function_returns_null = 1;
6362 /* Remember that this function did return a value. */
6363 current_function_returns_value = 1;
6365 /* Check for erroneous operands -- but after giving ourselves a
6366 chance to provide an error about returning a value from a void
6368 if (error_operand_p (retval))
6370 current_function_return_value = error_mark_node;
6371 return error_mark_node;
6374 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
6375 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
6376 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
6377 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
6379 && null_ptr_cst_p (retval))
6380 warning (0, "%<operator new%> must not return NULL unless it is "
6381 "declared %<throw()%> (or -fcheck-new is in effect)");
6383 /* Effective C++ rule 15. See also start_function. */
6385 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
6389 /* The function return type must be a reference to the current
6391 if (TREE_CODE (valtype) == REFERENCE_TYPE
6392 && same_type_ignoring_top_level_qualifiers_p
6393 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
6395 /* Returning '*this' is obviously OK. */
6396 if (retval == current_class_ref)
6398 /* If we are calling a function whose return type is the same of
6399 the current class reference, it is ok. */
6400 else if (TREE_CODE (retval) == INDIRECT_REF
6401 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
6406 warning (0, "%<operator=%> should return a reference to %<*this%>");
6409 /* The fabled Named Return Value optimization, as per [class.copy]/15:
6411 [...] For a function with a class return type, if the expression
6412 in the return statement is the name of a local object, and the cv-
6413 unqualified type of the local object is the same as the function
6414 return type, an implementation is permitted to omit creating the tem-
6415 porary object to hold the function return value [...]
6417 So, if this is a value-returning function that always returns the same
6418 local variable, remember it.
6420 It might be nice to be more flexible, and choose the first suitable
6421 variable even if the function sometimes returns something else, but
6422 then we run the risk of clobbering the variable we chose if the other
6423 returned expression uses the chosen variable somehow. And people expect
6424 this restriction, anyway. (jason 2000-11-19)
6426 See finish_function and finalize_nrv for the rest of this optimization. */
6428 if (fn_returns_value_p && flag_elide_constructors)
6430 if (retval != NULL_TREE
6431 && (current_function_return_value == NULL_TREE
6432 || current_function_return_value == retval)
6433 && TREE_CODE (retval) == VAR_DECL
6434 && DECL_CONTEXT (retval) == current_function_decl
6435 && ! TREE_STATIC (retval)
6436 && (DECL_ALIGN (retval)
6437 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6438 && same_type_p ((TYPE_MAIN_VARIANT
6439 (TREE_TYPE (retval))),
6441 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
6442 current_function_return_value = retval;
6444 current_function_return_value = error_mark_node;
6447 /* We don't need to do any conversions when there's nothing being
6452 /* Do any required conversions. */
6453 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6454 /* No conversions are required. */
6458 /* The type the function is declared to return. */
6459 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6461 /* The functype's return type will have been set to void, if it
6462 was an incomplete type. Just treat this as 'return;' */
6463 if (VOID_TYPE_P (functype))
6464 return error_mark_node;
6466 /* First convert the value to the function's return type, then
6467 to the type of return value's location to handle the
6468 case that functype is smaller than the valtype. */
6469 retval = convert_for_initialization
6470 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
6471 "return", NULL_TREE, 0);
6472 retval = convert (valtype, retval);
6474 /* If the conversion failed, treat this just like `return;'. */
6475 if (retval == error_mark_node)
6477 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6478 else if (! current_function_returns_struct
6479 && TREE_CODE (retval) == TARGET_EXPR
6480 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6481 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6482 TREE_OPERAND (retval, 0));
6484 maybe_warn_about_returning_address_of_local (retval);
6487 /* Actually copy the value returned into the appropriate location. */
6488 if (retval && retval != result)
6489 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
6495 /* Returns nonzero if the pointer-type FROM can be converted to the
6496 pointer-type TO via a qualification conversion. If CONSTP is -1,
6497 then we return nonzero if the pointers are similar, and the
6498 cv-qualification signature of FROM is a proper subset of that of TO.
6500 If CONSTP is positive, then all outer pointers have been
6504 comp_ptr_ttypes_real (tree to, tree from, int constp)
6506 bool to_more_cv_qualified = false;
6508 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6510 if (TREE_CODE (to) != TREE_CODE (from))
6513 if (TREE_CODE (from) == OFFSET_TYPE
6514 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
6515 TYPE_OFFSET_BASETYPE (to)))
6518 /* Const and volatile mean something different for function types,
6519 so the usual checks are not appropriate. */
6520 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6522 /* In Objective-C++, some types may have been 'volatilized' by
6523 the compiler for EH; when comparing them here, the volatile
6524 qualification must be ignored. */
6525 bool objc_quals_match = objc_type_quals_match (to, from);
6527 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
6530 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
6534 to_more_cv_qualified = true;
6538 constp &= TYPE_READONLY (to);
6541 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
6542 return ((constp >= 0 || to_more_cv_qualified)
6543 && same_type_ignoring_top_level_qualifiers_p (to, from));
6547 /* When comparing, say, char ** to char const **, this function takes
6548 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6549 types to this function. */
6552 comp_ptr_ttypes (tree to, tree from)
6554 return comp_ptr_ttypes_real (to, from, 1);
6557 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6558 type or inheritance-related types, regardless of cv-quals. */
6561 ptr_reasonably_similar (tree to, tree from)
6563 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6565 /* Any target type is similar enough to void. */
6566 if (TREE_CODE (to) == VOID_TYPE
6567 || TREE_CODE (from) == VOID_TYPE)
6570 if (TREE_CODE (to) != TREE_CODE (from))
6573 if (TREE_CODE (from) == OFFSET_TYPE
6574 && comptypes (TYPE_OFFSET_BASETYPE (to),
6575 TYPE_OFFSET_BASETYPE (from),
6576 COMPARE_BASE | COMPARE_DERIVED))
6579 if (TREE_CODE (to) == VECTOR_TYPE
6580 && vector_types_convertible_p (to, from))
6583 if (TREE_CODE (to) == INTEGER_TYPE
6584 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6587 if (TREE_CODE (to) == FUNCTION_TYPE)
6590 if (TREE_CODE (to) != POINTER_TYPE)
6592 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6593 COMPARE_BASE | COMPARE_DERIVED);
6597 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
6598 pointer-to-member types) are the same, ignoring cv-qualification at
6602 comp_ptr_ttypes_const (tree to, tree from)
6604 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6606 if (TREE_CODE (to) != TREE_CODE (from))
6609 if (TREE_CODE (from) == OFFSET_TYPE
6610 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6611 TYPE_OFFSET_BASETYPE (to)))
6614 if (TREE_CODE (to) != POINTER_TYPE)
6615 return same_type_ignoring_top_level_qualifiers_p (to, from);
6619 /* Returns the type qualifiers for this type, including the qualifiers on the
6620 elements for an array type. */
6623 cp_type_quals (tree type)
6625 type = strip_array_types (type);
6626 if (type == error_mark_node)
6627 return TYPE_UNQUALIFIED;
6628 return TYPE_QUALS (type);
6631 /* Returns nonzero if the TYPE contains a mutable member. */
6634 cp_has_mutable_p (tree type)
6636 type = strip_array_types (type);
6638 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6641 /* Apply the TYPE_QUALS to the new DECL. */
6643 cp_apply_type_quals_to_decl (int type_quals, tree decl)
6645 tree type = TREE_TYPE (decl);
6647 if (type == error_mark_node)
6650 if (TREE_CODE (type) == FUNCTION_TYPE
6651 && type_quals != TYPE_UNQUALIFIED)
6653 /* This was an error in C++98 (cv-qualifiers cannot be added to
6654 a function type), but DR 295 makes the code well-formed by
6655 dropping the extra qualifiers. */
6658 tree bad_type = build_qualified_type (type, type_quals);
6659 pedwarn ("ignoring %qV qualifiers added to function type %qT",
6663 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
6667 /* Avoid setting TREE_READONLY incorrectly. */
6668 if (/* If the object has a constructor, the constructor may modify
6670 TYPE_NEEDS_CONSTRUCTING (type)
6671 /* If the type isn't complete, we don't know yet if it will need
6673 || !COMPLETE_TYPE_P (type)
6674 /* If the type has a mutable component, that component might be
6676 || TYPE_HAS_MUTABLE_P (type))
6677 type_quals &= ~TYPE_QUAL_CONST;
6679 c_apply_type_quals_to_decl (type_quals, decl);
6682 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6683 exemplar types such that casting T1 to T2 is casting away constness
6684 if and only if there is no implicit conversion from T1 to T2. */
6687 casts_away_constness_r (tree *t1, tree *t2)
6692 /* [expr.const.cast]
6694 For multi-level pointer to members and multi-level mixed pointers
6695 and pointers to members (conv.qual), the "member" aspect of a
6696 pointer to member level is ignored when determining if a const
6697 cv-qualifier has been cast away. */
6698 /* [expr.const.cast]
6700 For two pointer types:
6702 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6703 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6706 casting from X1 to X2 casts away constness if, for a non-pointer
6707 type T there does not exist an implicit conversion (clause
6710 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6714 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6715 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
6716 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
6718 *t1 = cp_build_qualified_type (void_type_node,
6719 cp_type_quals (*t1));
6720 *t2 = cp_build_qualified_type (void_type_node,
6721 cp_type_quals (*t2));
6725 quals1 = cp_type_quals (*t1);
6726 quals2 = cp_type_quals (*t2);
6728 if (TYPE_PTRMEM_P (*t1))
6729 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
6731 *t1 = TREE_TYPE (*t1);
6732 if (TYPE_PTRMEM_P (*t2))
6733 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
6735 *t2 = TREE_TYPE (*t2);
6737 casts_away_constness_r (t1, t2);
6738 *t1 = build_pointer_type (*t1);
6739 *t2 = build_pointer_type (*t2);
6740 *t1 = cp_build_qualified_type (*t1, quals1);
6741 *t2 = cp_build_qualified_type (*t2, quals2);
6744 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6748 casts_away_constness (tree t1, tree t2)
6750 if (TREE_CODE (t2) == REFERENCE_TYPE)
6752 /* [expr.const.cast]
6754 Casting from an lvalue of type T1 to an lvalue of type T2
6755 using a reference cast casts away constness if a cast from an
6756 rvalue of type "pointer to T1" to the type "pointer to T2"
6757 casts away constness. */
6758 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6759 return casts_away_constness (build_pointer_type (t1),
6760 build_pointer_type (TREE_TYPE (t2)));
6763 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6764 /* [expr.const.cast]
6766 Casting from an rvalue of type "pointer to data member of X
6767 of type T1" to the type "pointer to data member of Y of type
6768 T2" casts away constness if a cast from an rvalue of type
6769 "pointer to T1" to the type "pointer to T2" casts away
6771 return casts_away_constness
6772 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6773 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6775 /* Casting away constness is only something that makes sense for
6776 pointer or reference types. */
6777 if (TREE_CODE (t1) != POINTER_TYPE
6778 || TREE_CODE (t2) != POINTER_TYPE)
6781 /* Top-level qualifiers don't matter. */
6782 t1 = TYPE_MAIN_VARIANT (t1);
6783 t2 = TYPE_MAIN_VARIANT (t2);
6784 casts_away_constness_r (&t1, &t2);
6785 if (!can_convert (t2, t1))
6791 /* If T is a REFERENCE_TYPE return the type to which T refers.
6792 Otherwise, return T itself. */
6795 non_reference (tree t)
6797 if (TREE_CODE (t) == REFERENCE_TYPE)
6803 /* Return nonzero if REF is an lvalue valid for this language;
6804 otherwise, print an error message and return zero. USE says
6805 how the lvalue is being used and so selects the error message. */
6808 lvalue_or_else (tree ref, enum lvalue_use use)
6810 int win = lvalue_p (ref);