1 /* Build expressions with type checking for C++ compiler.
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
4 Hacked by Michael Tiemann (tiemann@cygnus.com)
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to
20 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
24 /* This file is part of the C++ front end.
25 It contains routines to build C++ expressions given their operands,
26 including computing the types of the result, C and C++ specific error
27 checks, and some optimization. */
31 #include "coretypes.h"
41 #include "diagnostic.h"
46 static tree pfn_from_ptrmemfunc (tree);
47 static tree convert_for_assignment (tree, tree, const char *, tree, int);
48 static tree cp_pointer_int_sum (enum tree_code, tree, tree);
49 static tree rationalize_conditional_expr (enum tree_code, tree);
50 static int comp_ptr_ttypes_real (tree, tree, int);
51 static bool comp_except_types (tree, tree, bool);
52 static bool comp_array_types (tree, tree, bool);
53 static tree common_base_type (tree, tree);
54 static tree pointer_diff (tree, tree, tree);
55 static tree get_delta_difference (tree, tree, bool, bool);
56 static void casts_away_constness_r (tree *, tree *);
57 static bool casts_away_constness (tree, tree);
58 static void maybe_warn_about_returning_address_of_local (tree);
59 static tree lookup_destructor (tree, tree, tree);
60 static tree convert_arguments (tree, tree, tree, int);
62 /* Do `exp = require_complete_type (exp);' to make sure exp
63 does not have an incomplete type. (That includes void types.)
64 Returns the error_mark_node if the VALUE does not have
65 complete type when this function returns. */
68 require_complete_type (tree value)
72 if (processing_template_decl || value == error_mark_node)
75 if (TREE_CODE (value) == OVERLOAD)
76 type = unknown_type_node;
78 type = TREE_TYPE (value);
80 if (type == error_mark_node)
81 return error_mark_node;
83 /* First, detect a valid value with a complete type. */
84 if (COMPLETE_TYPE_P (type))
87 if (complete_type_or_else (type, value))
90 return error_mark_node;
93 /* Try to complete TYPE, if it is incomplete. For example, if TYPE is
94 a template instantiation, do the instantiation. Returns TYPE,
95 whether or not it could be completed, unless something goes
96 horribly wrong, in which case the error_mark_node is returned. */
99 complete_type (tree type)
101 if (type == NULL_TREE)
102 /* Rather than crash, we return something sure to cause an error
104 return error_mark_node;
106 if (type == error_mark_node || COMPLETE_TYPE_P (type))
108 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
110 tree t = complete_type (TREE_TYPE (type));
111 unsigned int needs_constructing, has_nontrivial_dtor;
112 if (COMPLETE_TYPE_P (t) && !dependent_type_p (type))
115 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
117 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
118 for (t = TYPE_MAIN_VARIANT (type); t; t = TYPE_NEXT_VARIANT (t))
120 TYPE_NEEDS_CONSTRUCTING (t) = needs_constructing;
121 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (t) = has_nontrivial_dtor;
124 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
125 instantiate_class_template (TYPE_MAIN_VARIANT (type));
130 /* Like complete_type, but issue an error if the TYPE cannot be completed.
131 VALUE is used for informative diagnostics.
132 Returns NULL_TREE if the type cannot be made complete. */
135 complete_type_or_else (tree type, tree value)
137 type = complete_type (type);
138 if (type == error_mark_node)
139 /* We already issued an error. */
141 else if (!COMPLETE_TYPE_P (type))
143 cxx_incomplete_type_diagnostic (value, type, 0);
150 /* Return truthvalue of whether type of EXP is instantiated. */
153 type_unknown_p (tree exp)
155 return (TREE_CODE (exp) == TREE_LIST
156 || TREE_TYPE (exp) == unknown_type_node);
160 /* Return the common type of two parameter lists.
161 We assume that comptypes has already been done and returned 1;
162 if that isn't so, this may crash.
164 As an optimization, free the space we allocate if the parameter
165 lists are already common. */
168 commonparms (tree p1, tree p2)
170 tree oldargs = p1, newargs, n;
174 len = list_length (p1);
175 newargs = tree_last (p1);
177 if (newargs == void_list_node)
186 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
191 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
193 if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
195 TREE_PURPOSE (n) = TREE_PURPOSE (p1);
198 else if (! TREE_PURPOSE (p1))
200 if (TREE_PURPOSE (p2))
202 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
208 if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
210 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
212 if (TREE_VALUE (p1) != TREE_VALUE (p2))
215 TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2));
218 TREE_VALUE (n) = TREE_VALUE (p1);
226 /* Given a type, perhaps copied for a typedef,
227 find the "original" version of it. */
229 original_type (tree t)
231 while (t != error_mark_node
232 && TYPE_NAME (t) != NULL_TREE)
234 tree x = TYPE_NAME (t);
235 if (TREE_CODE (x) != TYPE_DECL)
237 x = DECL_ORIGINAL_TYPE (x);
245 /* T1 and T2 are arithmetic or enumeration types. Return the type
246 that will result from the "usual arithmetic conversions" on T1 and
247 T2 as described in [expr]. */
250 type_after_usual_arithmetic_conversions (tree t1, tree t2)
252 enum tree_code code1 = TREE_CODE (t1);
253 enum tree_code code2 = TREE_CODE (t2);
256 /* FIXME: Attributes. */
257 gcc_assert (ARITHMETIC_TYPE_P (t1)
258 || TREE_CODE (t1) == COMPLEX_TYPE
259 || TREE_CODE (t1) == VECTOR_TYPE
260 || TREE_CODE (t1) == ENUMERAL_TYPE);
261 gcc_assert (ARITHMETIC_TYPE_P (t2)
262 || TREE_CODE (t2) == COMPLEX_TYPE
263 || TREE_CODE (t1) == VECTOR_TYPE
264 || TREE_CODE (t2) == ENUMERAL_TYPE);
266 /* In what follows, we slightly generalize the rules given in [expr] so
267 as to deal with `long long' and `complex'. First, merge the
269 attributes = (*targetm.merge_type_attributes) (t1, t2);
271 /* If one type is complex, form the common type of the non-complex
272 components, then make that complex. Use T1 or T2 if it is the
274 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
276 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
277 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
279 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
281 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
282 return build_type_attribute_variant (t1, attributes);
283 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
284 return build_type_attribute_variant (t2, attributes);
286 return build_type_attribute_variant (build_complex_type (subtype),
290 if (code1 == VECTOR_TYPE)
292 /* When we get here we should have two vectors of the same size.
293 Just prefer the unsigned one if present. */
294 if (TYPE_UNSIGNED (t1))
295 return build_type_attribute_variant (t1, attributes);
297 return build_type_attribute_variant (t2, attributes);
300 /* If only one is real, use it as the result. */
301 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
302 return build_type_attribute_variant (t1, attributes);
303 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
304 return build_type_attribute_variant (t2, attributes);
306 /* Perform the integral promotions. */
307 if (code1 != REAL_TYPE)
309 t1 = type_promotes_to (t1);
310 t2 = type_promotes_to (t2);
313 /* Both real or both integers; use the one with greater precision. */
314 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
315 return build_type_attribute_variant (t1, attributes);
316 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
317 return build_type_attribute_variant (t2, attributes);
319 /* The types are the same; no need to do anything fancy. */
320 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
321 return build_type_attribute_variant (t1, attributes);
323 if (code1 != REAL_TYPE)
325 /* If one is a sizetype, use it so size_binop doesn't blow up. */
326 if (TYPE_IS_SIZETYPE (t1) > TYPE_IS_SIZETYPE (t2))
327 return build_type_attribute_variant (t1, attributes);
328 if (TYPE_IS_SIZETYPE (t2) > TYPE_IS_SIZETYPE (t1))
329 return build_type_attribute_variant (t2, attributes);
331 /* If one is unsigned long long, then convert the other to unsigned
333 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
334 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
335 return build_type_attribute_variant (long_long_unsigned_type_node,
337 /* If one is a long long, and the other is an unsigned long, and
338 long long can represent all the values of an unsigned long, then
339 convert to a long long. Otherwise, convert to an unsigned long
340 long. Otherwise, if either operand is long long, convert the
343 Since we're here, we know the TYPE_PRECISION is the same;
344 therefore converting to long long cannot represent all the values
345 of an unsigned long, so we choose unsigned long long in that
347 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
348 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
350 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
351 ? long_long_unsigned_type_node
352 : long_long_integer_type_node);
353 return build_type_attribute_variant (t, attributes);
356 /* Go through the same procedure, but for longs. */
357 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
358 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
359 return build_type_attribute_variant (long_unsigned_type_node,
361 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
362 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
364 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
365 ? long_unsigned_type_node : long_integer_type_node);
366 return build_type_attribute_variant (t, attributes);
368 /* Otherwise prefer the unsigned one. */
369 if (TYPE_UNSIGNED (t1))
370 return build_type_attribute_variant (t1, attributes);
372 return build_type_attribute_variant (t2, attributes);
376 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
377 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
378 return build_type_attribute_variant (long_double_type_node,
380 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
381 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
382 return build_type_attribute_variant (double_type_node,
384 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
385 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
386 return build_type_attribute_variant (float_type_node,
389 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
390 the standard C++ floating-point types. Logic earlier in this
391 function has already eliminated the possibility that
392 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
393 compelling reason to choose one or the other. */
394 return build_type_attribute_variant (t1, attributes);
398 /* Subroutine of composite_pointer_type to implement the recursive
399 case. See that function for documentation fo the parameters. */
402 composite_pointer_type_r (tree t1, tree t2, const char* location)
409 /* Determine the types pointed to by T1 and T2. */
410 if (TREE_CODE (t1) == POINTER_TYPE)
412 pointee1 = TREE_TYPE (t1);
413 pointee2 = TREE_TYPE (t2);
417 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
418 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
423 Otherwise, the composite pointer type is a pointer type
424 similar (_conv.qual_) to the type of one of the operands,
425 with a cv-qualification signature (_conv.qual_) that is the
426 union of the cv-qualification signatures of the operand
428 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
429 result_type = pointee1;
430 else if ((TREE_CODE (pointee1) == POINTER_TYPE
431 && TREE_CODE (pointee2) == POINTER_TYPE)
432 || (TYPE_PTR_TO_MEMBER_P (pointee1)
433 && TYPE_PTR_TO_MEMBER_P (pointee2)))
434 result_type = composite_pointer_type_r (pointee1, pointee2, location);
437 pedwarn ("%s between distinct pointer types %qT and %qT "
440 result_type = void_type_node;
442 result_type = cp_build_qualified_type (result_type,
443 (cp_type_quals (pointee1)
444 | cp_type_quals (pointee2)));
445 /* If the original types were pointers to members, so is the
447 if (TYPE_PTR_TO_MEMBER_P (t1))
449 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
450 TYPE_PTRMEM_CLASS_TYPE (t2)))
451 pedwarn ("%s between distinct pointer types %qT and %qT "
454 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
458 result_type = build_pointer_type (result_type);
460 /* Merge the attributes. */
461 attributes = (*targetm.merge_type_attributes) (t1, t2);
462 return build_type_attribute_variant (result_type, attributes);
465 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
466 ARG1 and ARG2 are the values with those types. The LOCATION is a
467 string describing the current location, in case an error occurs.
469 This routine also implements the computation of a common type for
470 pointers-to-members as per [expr.eq]. */
473 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
474 const char* location)
481 If one operand is a null pointer constant, the composite pointer
482 type is the type of the other operand. */
483 if (null_ptr_cst_p (arg1))
485 if (null_ptr_cst_p (arg2))
492 If one of the operands has type "pointer to cv1 void*", then
493 the other has type "pointer to cv2T", and the composite pointer
494 type is "pointer to cv12 void", where cv12 is the union of cv1
497 If either type is a pointer to void, make sure it is T1. */
498 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
506 /* Now, if T1 is a pointer to void, merge the qualifiers. */
507 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
512 if (pedantic && TYPE_PTRFN_P (t2))
513 pedwarn ("ISO C++ forbids %s between pointer of type %<void *%> "
514 "and pointer-to-function", location);
516 = cp_build_qualified_type (void_type_node,
517 (cp_type_quals (TREE_TYPE (t1))
518 | cp_type_quals (TREE_TYPE (t2))));
519 result_type = build_pointer_type (result_type);
520 /* Merge the attributes. */
521 attributes = (*targetm.merge_type_attributes) (t1, t2);
522 return build_type_attribute_variant (result_type, attributes);
525 if (c_dialect_objc () && TREE_CODE (t1) == POINTER_TYPE
526 && TREE_CODE (t2) == POINTER_TYPE)
528 if (objc_compare_types (t1, t2, -3, NULL_TREE))
532 /* [expr.eq] permits the application of a pointer conversion to
533 bring the pointers to a common type. */
534 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
535 && CLASS_TYPE_P (TREE_TYPE (t1))
536 && CLASS_TYPE_P (TREE_TYPE (t2))
537 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
540 class1 = TREE_TYPE (t1);
541 class2 = TREE_TYPE (t2);
543 if (DERIVED_FROM_P (class1, class2))
544 t2 = (build_pointer_type
545 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
546 else if (DERIVED_FROM_P (class2, class1))
547 t1 = (build_pointer_type
548 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
551 error ("%s between distinct pointer types %qT and %qT "
552 "lacks a cast", location, t1, t2);
553 return error_mark_node;
556 /* [expr.eq] permits the application of a pointer-to-member
557 conversion to change the class type of one of the types. */
558 else if (TYPE_PTR_TO_MEMBER_P (t1)
559 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
560 TYPE_PTRMEM_CLASS_TYPE (t2)))
562 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
563 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
565 if (DERIVED_FROM_P (class1, class2))
566 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
567 else if (DERIVED_FROM_P (class2, class1))
568 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
571 error ("%s between distinct pointer-to-member types %qT and %qT "
572 "lacks a cast", location, t1, t2);
573 return error_mark_node;
577 return composite_pointer_type_r (t1, t2, location);
580 /* Return the merged type of two types.
581 We assume that comptypes has already been done and returned 1;
582 if that isn't so, this may crash.
584 This just combines attributes and default arguments; any other
585 differences would cause the two types to compare unalike. */
588 merge_types (tree t1, tree t2)
590 enum tree_code code1;
591 enum tree_code code2;
594 /* Save time if the two types are the same. */
597 if (original_type (t1) == original_type (t2))
600 /* If one type is nonsense, use the other. */
601 if (t1 == error_mark_node)
603 if (t2 == error_mark_node)
606 /* Merge the attributes. */
607 attributes = (*targetm.merge_type_attributes) (t1, t2);
609 if (TYPE_PTRMEMFUNC_P (t1))
610 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
611 if (TYPE_PTRMEMFUNC_P (t2))
612 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
614 code1 = TREE_CODE (t1);
615 code2 = TREE_CODE (t2);
621 /* For two pointers, do this recursively on the target type. */
623 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
624 int quals = cp_type_quals (t1);
626 if (code1 == POINTER_TYPE)
627 t1 = build_pointer_type (target);
629 t1 = build_reference_type (target);
630 t1 = build_type_attribute_variant (t1, attributes);
631 t1 = cp_build_qualified_type (t1, quals);
633 if (TREE_CODE (target) == METHOD_TYPE)
634 t1 = build_ptrmemfunc_type (t1);
643 quals = cp_type_quals (t1);
644 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
645 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
646 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
648 t1 = cp_build_qualified_type (t1, quals);
654 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
655 /* Save space: see if the result is identical to one of the args. */
656 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
657 return build_type_attribute_variant (t1, attributes);
658 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
659 return build_type_attribute_variant (t2, attributes);
660 /* Merge the element types, and have a size if either arg has one. */
661 t1 = build_cplus_array_type
662 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
667 /* Function types: prefer the one that specified arg types.
668 If both do, merge the arg types. Also merge the return types. */
670 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
671 tree p1 = TYPE_ARG_TYPES (t1);
672 tree p2 = TYPE_ARG_TYPES (t2);
675 /* Save space: see if the result is identical to one of the args. */
676 if (valtype == TREE_TYPE (t1) && ! p2)
677 return cp_build_type_attribute_variant (t1, attributes);
678 if (valtype == TREE_TYPE (t2) && ! p1)
679 return cp_build_type_attribute_variant (t2, attributes);
681 /* Simple way if one arg fails to specify argument types. */
682 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
684 rval = build_function_type (valtype, p2);
685 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
686 rval = build_exception_variant (rval, raises);
687 return cp_build_type_attribute_variant (rval, attributes);
689 raises = TYPE_RAISES_EXCEPTIONS (t1);
690 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
692 rval = build_function_type (valtype, p1);
694 rval = build_exception_variant (rval, raises);
695 return cp_build_type_attribute_variant (rval, attributes);
698 rval = build_function_type (valtype, commonparms (p1, p2));
699 t1 = build_exception_variant (rval, raises);
705 /* Get this value the long way, since TYPE_METHOD_BASETYPE
706 is just the main variant of this. */
707 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
708 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
711 /* If this was a member function type, get back to the
712 original type of type member function (i.e., without
713 the class instance variable up front. */
714 t1 = build_function_type (TREE_TYPE (t1),
715 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
716 t2 = build_function_type (TREE_TYPE (t2),
717 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
718 t3 = merge_types (t1, t2);
719 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
720 TYPE_ARG_TYPES (t3));
721 t1 = build_exception_variant (t3, raises);
726 /* There is no need to merge attributes into a TYPENAME_TYPE.
727 When the type is instantiated it will have whatever
728 attributes result from the instantiation. */
733 return cp_build_type_attribute_variant (t1, attributes);
736 /* Return the common type of two types.
737 We assume that comptypes has already been done and returned 1;
738 if that isn't so, this may crash.
740 This is the type for the result of most arithmetic operations
741 if the operands have the given two types. */
744 common_type (tree t1, tree t2)
746 enum tree_code code1;
747 enum tree_code code2;
749 /* If one type is nonsense, bail. */
750 if (t1 == error_mark_node || t2 == error_mark_node)
751 return error_mark_node;
753 code1 = TREE_CODE (t1);
754 code2 = TREE_CODE (t2);
756 if ((ARITHMETIC_TYPE_P (t1) || code1 == ENUMERAL_TYPE
757 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
758 && (ARITHMETIC_TYPE_P (t2) || code2 == ENUMERAL_TYPE
759 || code2 == COMPLEX_TYPE || code2 == VECTOR_TYPE))
760 return type_after_usual_arithmetic_conversions (t1, t2);
762 else if ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
763 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
764 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)))
765 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
771 /* Compare two exception specifier types for exactness or subsetness, if
772 allowed. Returns false for mismatch, true for match (same, or
775 [except.spec] "If a class X ... objects of class X or any class publicly
776 and unambiguously derived from X. Similarly, if a pointer type Y * ...
777 exceptions of type Y * or that are pointers to any type publicly and
778 unambiguously derived from Y. Otherwise a function only allows exceptions
779 that have the same type ..."
780 This does not mention cv qualifiers and is different to what throw
781 [except.throw] and catch [except.catch] will do. They will ignore the
782 top level cv qualifiers, and allow qualifiers in the pointer to class
785 We implement the letter of the standard. */
788 comp_except_types (tree a, tree b, bool exact)
790 if (same_type_p (a, b))
794 if (cp_type_quals (a) || cp_type_quals (b))
797 if (TREE_CODE (a) == POINTER_TYPE
798 && TREE_CODE (b) == POINTER_TYPE)
802 if (cp_type_quals (a) || cp_type_quals (b))
806 if (TREE_CODE (a) != RECORD_TYPE
807 || TREE_CODE (b) != RECORD_TYPE)
810 if (PUBLICLY_UNIQUELY_DERIVED_P (a, b))
816 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
817 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
818 otherwise it must be exact. Exception lists are unordered, but
819 we've already filtered out duplicates. Most lists will be in order,
820 we should try to make use of that. */
823 comp_except_specs (tree t1, tree t2, bool exact)
832 if (t1 == NULL_TREE) /* T1 is ... */
833 return t2 == NULL_TREE || !exact;
834 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
835 return t2 != NULL_TREE && !TREE_VALUE (t2);
836 if (t2 == NULL_TREE) /* T2 is ... */
838 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
841 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
842 Count how many we find, to determine exactness. For exact matching and
843 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
845 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
847 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
849 tree a = TREE_VALUE (probe);
850 tree b = TREE_VALUE (t2);
852 if (comp_except_types (a, b, exact))
854 if (probe == base && exact)
855 base = TREE_CHAIN (probe);
860 if (probe == NULL_TREE)
863 return !exact || base == NULL_TREE || length == list_length (t1);
866 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
867 [] can match [size]. */
870 comp_array_types (tree t1, tree t2, bool allow_redeclaration)
879 /* The type of the array elements must be the same. */
880 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
883 d1 = TYPE_DOMAIN (t1);
884 d2 = TYPE_DOMAIN (t2);
889 /* If one of the arrays is dimensionless, and the other has a
890 dimension, they are of different types. However, it is valid to
898 declarations for an array object can specify
899 array types that differ by the presence or absence of a major
900 array bound (_dcl.array_). */
902 return allow_redeclaration;
904 /* Check that the dimensions are the same. */
906 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
908 max1 = TYPE_MAX_VALUE (d1);
909 max2 = TYPE_MAX_VALUE (d2);
910 if (processing_template_decl && !abi_version_at_least (2)
911 && !value_dependent_expression_p (max1)
912 && !value_dependent_expression_p (max2))
914 /* With abi-1 we do not fold non-dependent array bounds, (and
915 consequently mangle them incorrectly). We must therefore
916 fold them here, to verify the domains have the same
922 if (!cp_tree_equal (max1, max2))
928 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
929 is a bitwise-or of the COMPARE_* flags. */
932 comptypes (tree t1, tree t2, int strict)
937 /* Suppress errors caused by previously reported errors. */
938 if (t1 == error_mark_node || t2 == error_mark_node)
941 gcc_assert (TYPE_P (t1) && TYPE_P (t2));
943 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
944 current instantiation. */
945 if (TREE_CODE (t1) == TYPENAME_TYPE)
947 tree resolved = resolve_typename_type (t1, /*only_current_p=*/true);
949 if (resolved != error_mark_node)
953 if (TREE_CODE (t2) == TYPENAME_TYPE)
955 tree resolved = resolve_typename_type (t2, /*only_current_p=*/true);
957 if (resolved != error_mark_node)
961 /* If either type is the internal version of sizetype, use the
963 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
964 && TYPE_ORIG_SIZE_TYPE (t1))
965 t1 = TYPE_ORIG_SIZE_TYPE (t1);
967 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
968 && TYPE_ORIG_SIZE_TYPE (t2))
969 t2 = TYPE_ORIG_SIZE_TYPE (t2);
971 if (TYPE_PTRMEMFUNC_P (t1))
972 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
973 if (TYPE_PTRMEMFUNC_P (t2))
974 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
976 /* Different classes of types can't be compatible. */
977 if (TREE_CODE (t1) != TREE_CODE (t2))
980 /* Qualifiers must match. For array types, we will check when we
981 recur on the array element types. */
982 if (TREE_CODE (t1) != ARRAY_TYPE
983 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
985 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
988 /* Allow for two different type nodes which have essentially the same
989 definition. Note that we already checked for equality of the type
990 qualifiers (just above). */
992 if (TREE_CODE (t1) != ARRAY_TYPE
993 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
996 /* Compare the types. Break out if they could be the same. */
997 switch (TREE_CODE (t1))
999 case TEMPLATE_TEMPLATE_PARM:
1000 case BOUND_TEMPLATE_TEMPLATE_PARM:
1001 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1002 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
1004 if (!comp_template_parms
1005 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1006 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1008 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1010 /* Don't check inheritance. */
1011 strict = COMPARE_STRICT;
1016 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1017 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1018 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1019 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1022 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1024 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1030 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1031 strict & ~COMPARE_REDECLARATION))
1033 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1038 case REFERENCE_TYPE:
1039 if (TYPE_MODE (t1) != TYPE_MODE (t2)
1040 || TYPE_REF_CAN_ALIAS_ALL (t1) != TYPE_REF_CAN_ALIAS_ALL (t2)
1041 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1047 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1049 if (!compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2)))
1054 /* Target types must match incl. qualifiers. */
1055 if (!comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION)))
1059 case TEMPLATE_TYPE_PARM:
1060 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
1061 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
1066 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1067 TYPENAME_TYPE_FULLNAME (t2)))
1069 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1073 case UNBOUND_CLASS_TEMPLATE:
1074 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1076 if (!same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2)))
1081 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1086 if (TYPE_VECTOR_SUBPARTS (t1) != TYPE_VECTOR_SUBPARTS (t2)
1087 || !same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1095 /* If we get here, we know that from a target independent POV the
1096 types are the same. Make sure the target attributes are also
1098 return targetm.comp_type_attributes (t1, t2);
1101 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1104 at_least_as_qualified_p (tree type1, tree type2)
1106 int q1 = cp_type_quals (type1);
1107 int q2 = cp_type_quals (type2);
1109 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1110 return (q1 & q2) == q2;
1113 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1114 more cv-qualified that TYPE1, and 0 otherwise. */
1117 comp_cv_qualification (tree type1, tree type2)
1119 int q1 = cp_type_quals (type1);
1120 int q2 = cp_type_quals (type2);
1125 if ((q1 & q2) == q2)
1127 else if ((q1 & q2) == q1)
1133 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1134 subset of the cv-qualification signature of TYPE2, and the types
1135 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1138 comp_cv_qual_signature (tree type1, tree type2)
1140 if (comp_ptr_ttypes_real (type2, type1, -1))
1142 else if (comp_ptr_ttypes_real (type1, type2, -1))
1148 /* If two types share a common base type, return that basetype.
1149 If there is not a unique most-derived base type, this function
1150 returns ERROR_MARK_NODE. */
1153 common_base_type (tree tt1, tree tt2)
1155 tree best = NULL_TREE;
1158 /* If one is a baseclass of another, that's good enough. */
1159 if (UNIQUELY_DERIVED_FROM_P (tt1, tt2))
1161 if (UNIQUELY_DERIVED_FROM_P (tt2, tt1))
1164 /* Otherwise, try to find a unique baseclass of TT1
1165 that is shared by TT2, and follow that down. */
1166 for (i = BINFO_N_BASE_BINFOS (TYPE_BINFO (tt1))-1; i >= 0; i--)
1168 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (tt1), i));
1169 tree trial = common_base_type (basetype, tt2);
1173 if (trial == error_mark_node)
1175 if (best == NULL_TREE)
1177 else if (best != trial)
1178 return error_mark_node;
1183 for (i = BINFO_N_BASE_BINFOS (TYPE_BINFO (tt2))-1; i >= 0; i--)
1185 tree basetype = BINFO_TYPE (BINFO_BASE_BINFO (TYPE_BINFO (tt2), i));
1186 tree trial = common_base_type (tt1, basetype);
1190 if (trial == error_mark_node)
1192 if (best == NULL_TREE)
1194 else if (best != trial)
1195 return error_mark_node;
1201 /* Subroutines of `comptypes'. */
1203 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1204 equivalent in the sense that functions with those parameter types
1205 can have equivalent types. The two lists must be equivalent,
1206 element by element. */
1209 compparms (tree parms1, tree parms2)
1213 /* An unspecified parmlist matches any specified parmlist
1214 whose argument types don't need default promotions. */
1216 for (t1 = parms1, t2 = parms2;
1218 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1220 /* If one parmlist is shorter than the other,
1221 they fail to match. */
1224 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1231 /* Process a sizeof or alignof expression where the operand is a
1235 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1237 enum tree_code type_code;
1239 const char *op_name;
1241 gcc_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR);
1242 if (type == error_mark_node)
1243 return error_mark_node;
1245 if (dependent_type_p (type))
1247 value = build_min (op, size_type_node, type);
1248 TREE_READONLY (value) = 1;
1252 op_name = operator_name_info[(int) op].name;
1254 type = non_reference (type);
1255 type_code = TREE_CODE (type);
1257 if (type_code == METHOD_TYPE)
1259 if (complain && (pedantic || warn_pointer_arith))
1260 pedwarn ("invalid application of %qs to a member function", op_name);
1261 value = size_one_node;
1264 value = c_sizeof_or_alignof_type (complete_type (type),
1271 /* Process a sizeof expression where the operand is an expression. */
1274 cxx_sizeof_expr (tree e)
1276 if (e == error_mark_node)
1277 return error_mark_node;
1279 if (processing_template_decl)
1281 e = build_min (SIZEOF_EXPR, size_type_node, e);
1282 TREE_SIDE_EFFECTS (e) = 0;
1283 TREE_READONLY (e) = 1;
1288 if (TREE_CODE (e) == COMPONENT_REF
1289 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1290 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1292 error ("invalid application of %<sizeof%> to a bit-field");
1295 else if (is_overloaded_fn (e))
1297 pedwarn ("ISO C++ forbids applying %<sizeof%> to an expression of "
1301 else if (type_unknown_p (e))
1303 cxx_incomplete_type_error (e, TREE_TYPE (e));
1309 return cxx_sizeof_or_alignof_type (e, SIZEOF_EXPR, true);
1312 /* Implement the __alignof keyword: Return the minimum required
1313 alignment of E, measured in bytes. For VAR_DECL's and
1314 FIELD_DECL's return DECL_ALIGN (which can be set from an
1315 "aligned" __attribute__ specification). */
1318 cxx_alignof_expr (tree e)
1322 if (e == error_mark_node)
1323 return error_mark_node;
1325 if (processing_template_decl)
1327 e = build_min (ALIGNOF_EXPR, size_type_node, e);
1328 TREE_SIDE_EFFECTS (e) = 0;
1329 TREE_READONLY (e) = 1;
1334 if (TREE_CODE (e) == VAR_DECL)
1335 t = size_int (DECL_ALIGN_UNIT (e));
1336 else if (TREE_CODE (e) == COMPONENT_REF
1337 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1338 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1340 error ("invalid application of %<__alignof%> to a bit-field");
1343 else if (TREE_CODE (e) == COMPONENT_REF
1344 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL)
1345 t = size_int (DECL_ALIGN_UNIT (TREE_OPERAND (e, 1)));
1346 else if (is_overloaded_fn (e))
1348 pedwarn ("ISO C++ forbids applying %<__alignof%> to an expression of "
1352 else if (type_unknown_p (e))
1354 cxx_incomplete_type_error (e, TREE_TYPE (e));
1358 return cxx_sizeof_or_alignof_type (TREE_TYPE (e), ALIGNOF_EXPR, true);
1360 return fold_convert (size_type_node, t);
1363 /* Process a sizeof or alignof expression E with code OP where the operand
1364 is an expression. */
1367 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op)
1369 if (op == SIZEOF_EXPR)
1370 return cxx_sizeof_expr (e);
1372 return cxx_alignof_expr (e);
1375 /* EXPR is being used in a context that is not a function call.
1380 The expression can be used only as the left-hand operand of a
1381 member function call.
1383 [expr.mptr.operator]
1385 If the result of .* or ->* is a function, then that result can be
1386 used only as the operand for the function call operator ().
1388 by issuing an error message if appropriate. Returns true iff EXPR
1389 violates these rules. */
1392 invalid_nonstatic_memfn_p (tree expr)
1394 if (TREE_CODE (TREE_TYPE (expr)) == METHOD_TYPE)
1396 error ("invalid use of non-static member function");
1402 /* If EXP is a reference to a bitfield, and the type of EXP does not
1403 match the declared type of the bitfield, return the declared type
1404 of the bitfield. Otherwise, return NULL_TREE. */
1407 is_bitfield_expr_with_lowered_type (tree exp)
1411 if (TREE_CODE (exp) == COND_EXPR)
1413 if (!is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 1)))
1415 return is_bitfield_expr_with_lowered_type (TREE_OPERAND (exp, 2));
1417 if (TREE_CODE (exp) != COMPONENT_REF)
1419 field = TREE_OPERAND (exp, 1);
1420 if (TREE_CODE (field) != FIELD_DECL || !DECL_C_BIT_FIELD (field))
1422 if (same_type_ignoring_top_level_qualifiers_p
1423 (TREE_TYPE (exp), DECL_BIT_FIELD_TYPE (field)))
1425 return DECL_BIT_FIELD_TYPE (field);
1428 /* Perform the conversions in [expr] that apply when an lvalue appears
1429 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1430 function-to-pointer conversions. In addition, manifest constants
1431 are replaced by their values, and bitfield references are converted
1432 to their declared types.
1434 Although the returned value is being used as an rvalue, this
1435 function does not wrap the returned expression in a
1436 NON_LVALUE_EXPR; the caller is expected to be mindful of the fact
1437 that the return value is no longer an lvalue. */
1440 decay_conversion (tree exp)
1443 enum tree_code code;
1445 type = TREE_TYPE (exp);
1446 if (type == error_mark_node)
1447 return error_mark_node;
1449 if (type_unknown_p (exp))
1451 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1452 return error_mark_node;
1455 exp = decl_constant_value (exp);
1456 if (error_operand_p (exp))
1457 return error_mark_node;
1459 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1460 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1461 code = TREE_CODE (type);
1462 if (code == VOID_TYPE)
1464 error ("void value not ignored as it ought to be");
1465 return error_mark_node;
1467 if (invalid_nonstatic_memfn_p (exp))
1468 return error_mark_node;
1469 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1470 return build_unary_op (ADDR_EXPR, exp, 0);
1471 if (code == ARRAY_TYPE)
1476 if (TREE_CODE (exp) == INDIRECT_REF)
1477 return build_nop (build_pointer_type (TREE_TYPE (type)),
1478 TREE_OPERAND (exp, 0));
1480 if (TREE_CODE (exp) == COMPOUND_EXPR)
1482 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1483 return build2 (COMPOUND_EXPR, TREE_TYPE (op1),
1484 TREE_OPERAND (exp, 0), op1);
1488 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1490 error ("invalid use of non-lvalue array");
1491 return error_mark_node;
1494 ptrtype = build_pointer_type (TREE_TYPE (type));
1496 if (TREE_CODE (exp) == VAR_DECL)
1498 if (!cxx_mark_addressable (exp))
1499 return error_mark_node;
1500 adr = build_nop (ptrtype, build_address (exp));
1503 /* This way is better for a COMPONENT_REF since it can
1504 simplify the offset for a component. */
1505 adr = build_unary_op (ADDR_EXPR, exp, 1);
1506 return cp_convert (ptrtype, adr);
1509 /* If a bitfield is used in a context where integral promotion
1510 applies, then the caller is expected to have used
1511 default_conversion. That function promotes bitfields correctly
1512 before calling this function. At this point, if we have a
1513 bitfield referenced, we may assume that is not subject to
1514 promotion, and that, therefore, the type of the resulting rvalue
1515 is the declared type of the bitfield. */
1516 exp = convert_bitfield_to_declared_type (exp);
1518 /* We do not call rvalue() here because we do not want to wrap EXP
1519 in a NON_LVALUE_EXPR. */
1523 Non-class rvalues always have cv-unqualified types. */
1524 type = TREE_TYPE (exp);
1525 if (!CLASS_TYPE_P (type) && cp_type_quals (type))
1526 exp = build_nop (TYPE_MAIN_VARIANT (type), exp);
1531 /* Perform prepatory conversions, as part of the "usual arithmetic
1532 conversions". In particular, as per [expr]:
1534 Whenever an lvalue expression appears as an operand of an
1535 operator that expects the rvalue for that operand, the
1536 lvalue-to-rvalue, array-to-pointer, or function-to-pointer
1537 standard conversions are applied to convert the expression to an
1540 In addition, we perform integral promotions here, as those are
1541 applied to both operands to a binary operator before determining
1542 what additional conversions should apply. */
1545 default_conversion (tree exp)
1547 /* Perform the integral promotions first so that bitfield
1548 expressions (which may promote to "int", even if the bitfield is
1549 declared "unsigned") are promoted correctly. */
1550 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1551 exp = perform_integral_promotions (exp);
1552 /* Perform the other conversions. */
1553 exp = decay_conversion (exp);
1558 /* EXPR is an expression with an integral or enumeration type.
1559 Perform the integral promotions in [conv.prom], and return the
1563 perform_integral_promotions (tree expr)
1570 If the bitfield has an enumerated type, it is treated as any
1571 other value of that type for promotion purposes. */
1572 type = is_bitfield_expr_with_lowered_type (expr);
1573 if (!type || TREE_CODE (type) != ENUMERAL_TYPE)
1574 type = TREE_TYPE (expr);
1575 gcc_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type));
1576 promoted_type = type_promotes_to (type);
1577 if (type != promoted_type)
1578 expr = cp_convert (promoted_type, expr);
1582 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1586 inline_conversion (tree exp)
1588 if (TREE_CODE (exp) == FUNCTION_DECL)
1589 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1594 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1595 decay_conversion to one. */
1598 string_conv_p (tree totype, tree exp, int warn)
1602 if (TREE_CODE (totype) != POINTER_TYPE)
1605 t = TREE_TYPE (totype);
1606 if (!same_type_p (t, char_type_node)
1607 && !same_type_p (t, wchar_type_node))
1610 if (TREE_CODE (exp) == STRING_CST)
1612 /* Make sure that we don't try to convert between char and wchar_t. */
1613 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1618 /* Is this a string constant which has decayed to 'const char *'? */
1619 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1620 if (!same_type_p (TREE_TYPE (exp), t))
1623 if (TREE_CODE (exp) != ADDR_EXPR
1624 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1628 /* This warning is not very useful, as it complains about printf. */
1630 warning (OPT_Wwrite_strings, "deprecated conversion from string constant to %qT'", totype);
1635 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1636 can, for example, use as an lvalue. This code used to be in
1637 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1638 expressions, where we're dealing with aggregates. But now it's again only
1639 called from unary_complex_lvalue. The case (in particular) that led to
1640 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1644 rationalize_conditional_expr (enum tree_code code, tree t)
1646 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1647 the first operand is always the one to be used if both operands
1648 are equal, so we know what conditional expression this used to be. */
1649 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1651 /* The following code is incorrect if either operand side-effects. */
1652 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (t, 0))
1653 && !TREE_SIDE_EFFECTS (TREE_OPERAND (t, 1)));
1655 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1656 ? LE_EXPR : GE_EXPR),
1657 TREE_OPERAND (t, 0),
1658 TREE_OPERAND (t, 1),
1659 /*overloaded_p=*/NULL),
1660 build_unary_op (code, TREE_OPERAND (t, 0), 0),
1661 build_unary_op (code, TREE_OPERAND (t, 1), 0));
1665 build_conditional_expr (TREE_OPERAND (t, 0),
1666 build_unary_op (code, TREE_OPERAND (t, 1), 0),
1667 build_unary_op (code, TREE_OPERAND (t, 2), 0));
1670 /* Given the TYPE of an anonymous union field inside T, return the
1671 FIELD_DECL for the field. If not found return NULL_TREE. Because
1672 anonymous unions can nest, we must also search all anonymous unions
1673 that are directly reachable. */
1676 lookup_anon_field (tree t, tree type)
1680 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1682 if (TREE_STATIC (field))
1684 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1687 /* If we find it directly, return the field. */
1688 if (DECL_NAME (field) == NULL_TREE
1689 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1694 /* Otherwise, it could be nested, search harder. */
1695 if (DECL_NAME (field) == NULL_TREE
1696 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1698 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1706 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1707 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1708 non-NULL, it indicates the path to the base used to name MEMBER.
1709 If PRESERVE_REFERENCE is true, the expression returned will have
1710 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1711 returned will have the type referred to by the reference.
1713 This function does not perform access control; that is either done
1714 earlier by the parser when the name of MEMBER is resolved to MEMBER
1715 itself, or later when overload resolution selects one of the
1716 functions indicated by MEMBER. */
1719 build_class_member_access_expr (tree object, tree member,
1720 tree access_path, bool preserve_reference)
1724 tree result = NULL_TREE;
1726 if (object == error_mark_node || member == error_mark_node)
1727 return error_mark_node;
1729 gcc_assert (DECL_P (member) || BASELINK_P (member));
1733 The type of the first expression shall be "class object" (of a
1735 object_type = TREE_TYPE (object);
1736 if (!currently_open_class (object_type)
1737 && !complete_type_or_else (object_type, object))
1738 return error_mark_node;
1739 if (!CLASS_TYPE_P (object_type))
1741 error ("request for member %qD in %qE, which is of non-class type %qT",
1742 member, object, object_type);
1743 return error_mark_node;
1746 /* The standard does not seem to actually say that MEMBER must be a
1747 member of OBJECT_TYPE. However, that is clearly what is
1749 if (DECL_P (member))
1751 member_scope = DECL_CLASS_CONTEXT (member);
1753 if (TREE_DEPRECATED (member))
1754 warn_deprecated_use (member);
1757 member_scope = BINFO_TYPE (BASELINK_BINFO (member));
1758 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1759 presently be the anonymous union. Go outwards until we find a
1760 type related to OBJECT_TYPE. */
1761 while (ANON_AGGR_TYPE_P (member_scope)
1762 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1764 member_scope = TYPE_CONTEXT (member_scope);
1765 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1767 if (TREE_CODE (member) == FIELD_DECL)
1768 error ("invalid use of nonstatic data member %qE", member);
1770 error ("%qD is not a member of %qT", member, object_type);
1771 return error_mark_node;
1774 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1775 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1776 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1778 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1780 object = build_indirect_ref (temp, NULL);
1783 /* In [expr.ref], there is an explicit list of the valid choices for
1784 MEMBER. We check for each of those cases here. */
1785 if (TREE_CODE (member) == VAR_DECL)
1787 /* A static data member. */
1789 /* If OBJECT has side-effects, they are supposed to occur. */
1790 if (TREE_SIDE_EFFECTS (object))
1791 result = build2 (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1793 else if (TREE_CODE (member) == FIELD_DECL)
1795 /* A non-static data member. */
1800 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1801 && integer_zerop (TREE_OPERAND (object, 0)));
1803 /* Convert OBJECT to the type of MEMBER. */
1804 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1805 TYPE_MAIN_VARIANT (member_scope)))
1810 binfo = lookup_base (access_path ? access_path : object_type,
1811 member_scope, ba_unique, &kind);
1812 if (binfo == error_mark_node)
1813 return error_mark_node;
1815 /* It is invalid to try to get to a virtual base of a
1816 NULL object. The most common cause is invalid use of
1818 if (null_object_p && kind == bk_via_virtual)
1820 error ("invalid access to non-static data member %qD of "
1823 error ("(perhaps the %<offsetof%> macro was used incorrectly)");
1824 return error_mark_node;
1827 /* Convert to the base. */
1828 object = build_base_path (PLUS_EXPR, object, binfo,
1830 /* If we found the base successfully then we should be able
1831 to convert to it successfully. */
1832 gcc_assert (object != error_mark_node);
1835 /* Complain about other invalid uses of offsetof, even though they will
1836 give the right answer. Note that we complain whether or not they
1837 actually used the offsetof macro, since there's no way to know at this
1838 point. So we just give a warning, instead of a pedwarn. */
1839 /* Do not produce this warning for base class field references, because
1840 we know for a fact that didn't come from offsetof. This does occur
1841 in various testsuite cases where a null object is passed where a
1842 vtable access is required. */
1843 if (null_object_p && warn_invalid_offsetof
1844 && CLASSTYPE_NON_POD_P (object_type)
1845 && !DECL_FIELD_IS_BASE (member)
1846 && !skip_evaluation)
1848 warning (0, "invalid access to non-static data member %qD of NULL object",
1850 warning (0, "(perhaps the %<offsetof%> macro was used incorrectly)");
1853 /* If MEMBER is from an anonymous aggregate, we have converted
1854 OBJECT so that it refers to the class containing the
1855 anonymous union. Generate a reference to the anonymous union
1856 itself, and recur to find MEMBER. */
1857 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
1858 /* When this code is called from build_field_call, the
1859 object already has the type of the anonymous union.
1860 That is because the COMPONENT_REF was already
1861 constructed, and was then disassembled before calling
1862 build_field_call. After the function-call code is
1863 cleaned up, this waste can be eliminated. */
1864 && (!same_type_ignoring_top_level_qualifiers_p
1865 (TREE_TYPE (object), DECL_CONTEXT (member))))
1867 tree anonymous_union;
1869 anonymous_union = lookup_anon_field (TREE_TYPE (object),
1870 DECL_CONTEXT (member));
1871 object = build_class_member_access_expr (object,
1873 /*access_path=*/NULL_TREE,
1874 preserve_reference);
1877 /* Compute the type of the field, as described in [expr.ref]. */
1878 type_quals = TYPE_UNQUALIFIED;
1879 member_type = TREE_TYPE (member);
1880 if (TREE_CODE (member_type) != REFERENCE_TYPE)
1882 type_quals = (cp_type_quals (member_type)
1883 | cp_type_quals (object_type));
1885 /* A field is const (volatile) if the enclosing object, or the
1886 field itself, is const (volatile). But, a mutable field is
1887 not const, even within a const object. */
1888 if (DECL_MUTABLE_P (member))
1889 type_quals &= ~TYPE_QUAL_CONST;
1890 member_type = cp_build_qualified_type (member_type, type_quals);
1893 result = build3 (COMPONENT_REF, member_type, object, member,
1895 result = fold_if_not_in_template (result);
1897 /* Mark the expression const or volatile, as appropriate. Even
1898 though we've dealt with the type above, we still have to mark the
1899 expression itself. */
1900 if (type_quals & TYPE_QUAL_CONST)
1901 TREE_READONLY (result) = 1;
1902 if (type_quals & TYPE_QUAL_VOLATILE)
1903 TREE_THIS_VOLATILE (result) = 1;
1905 else if (BASELINK_P (member))
1907 /* The member is a (possibly overloaded) member function. */
1911 /* If the MEMBER is exactly one static member function, then we
1912 know the type of the expression. Otherwise, we must wait
1913 until overload resolution has been performed. */
1914 functions = BASELINK_FUNCTIONS (member);
1915 if (TREE_CODE (functions) == FUNCTION_DECL
1916 && DECL_STATIC_FUNCTION_P (functions))
1917 type = TREE_TYPE (functions);
1919 type = unknown_type_node;
1920 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1921 base. That will happen when the function is called. */
1922 result = build3 (COMPONENT_REF, type, object, member, NULL_TREE);
1924 else if (TREE_CODE (member) == CONST_DECL)
1926 /* The member is an enumerator. */
1928 /* If OBJECT has side-effects, they are supposed to occur. */
1929 if (TREE_SIDE_EFFECTS (object))
1930 result = build2 (COMPOUND_EXPR, TREE_TYPE (result),
1935 error ("invalid use of %qD", member);
1936 return error_mark_node;
1939 if (!preserve_reference)
1942 If E2 is declared to have type "reference to T", then ... the
1943 type of E1.E2 is T. */
1944 result = convert_from_reference (result);
1949 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1950 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1953 lookup_destructor (tree object, tree scope, tree dtor_name)
1955 tree object_type = TREE_TYPE (object);
1956 tree dtor_type = TREE_OPERAND (dtor_name, 0);
1959 if (scope && !check_dtor_name (scope, dtor_type))
1961 error ("qualified type %qT does not match destructor name ~%qT",
1963 return error_mark_node;
1965 if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
1967 error ("the type being destroyed is %qT, but the destructor refers to %qT",
1968 TYPE_MAIN_VARIANT (object_type), dtor_type);
1969 return error_mark_node;
1971 expr = lookup_member (dtor_type, complete_dtor_identifier,
1972 /*protect=*/1, /*want_type=*/false);
1973 expr = (adjust_result_of_qualified_name_lookup
1974 (expr, dtor_type, object_type));
1978 /* An expression of the form "A::template B" has been resolved to
1979 DECL. Issue a diagnostic if B is not a template or template
1983 check_template_keyword (tree decl)
1985 /* The standard says:
1989 If a name prefixed by the keyword template is not a member
1990 template, the program is ill-formed.
1992 DR 228 removed the restriction that the template be a member
1995 DR 96, if accepted would add the further restriction that explicit
1996 template arguments must be provided if the template keyword is
1997 used, but, as of 2005-10-16, that DR is still in "drafting". If
1998 this DR is accepted, then the semantic checks here can be
1999 simplified, as the entity named must in fact be a template
2000 specialization, rather than, as at present, a set of overloaded
2001 functions containing at least one template function. */
2002 if (TREE_CODE (decl) != TEMPLATE_DECL
2003 && TREE_CODE (decl) != TEMPLATE_ID_EXPR)
2005 if (!is_overloaded_fn (decl))
2006 pedwarn ("%qD is not a template", decl);
2011 if (BASELINK_P (fns))
2012 fns = BASELINK_FUNCTIONS (fns);
2015 tree fn = OVL_CURRENT (fns);
2016 if (TREE_CODE (fn) == TEMPLATE_DECL
2017 || TREE_CODE (fn) == TEMPLATE_ID_EXPR)
2019 if (TREE_CODE (fn) == FUNCTION_DECL
2020 && DECL_USE_TEMPLATE (fn)
2021 && PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (fn)))
2023 fns = OVL_NEXT (fns);
2026 pedwarn ("%qD is not a template", decl);
2031 /* This function is called by the parser to process a class member
2032 access expression of the form OBJECT.NAME. NAME is a node used by
2033 the parser to represent a name; it is not yet a DECL. It may,
2034 however, be a BASELINK where the BASELINK_FUNCTIONS is a
2035 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
2036 there is no reason to do the lookup twice, so the parser keeps the
2037 BASELINK. TEMPLATE_P is true iff NAME was explicitly declared to
2038 be a template via the use of the "A::template B" syntax. */
2041 finish_class_member_access_expr (tree object, tree name, bool template_p)
2046 tree access_path = NULL_TREE;
2047 tree orig_object = object;
2048 tree orig_name = name;
2050 if (object == error_mark_node || name == error_mark_node)
2051 return error_mark_node;
2053 /* If OBJECT is an ObjC class instance, we must obey ObjC access rules. */
2054 if (!objc_is_public (object, name))
2055 return error_mark_node;
2057 object_type = TREE_TYPE (object);
2059 if (processing_template_decl)
2061 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
2062 dependent_type_p (object_type)
2063 /* If NAME is just an IDENTIFIER_NODE, then the expression
2065 || TREE_CODE (object) == IDENTIFIER_NODE
2066 /* If NAME is "f<args>", where either 'f' or 'args' is
2067 dependent, then the expression is dependent. */
2068 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
2069 && dependent_template_id_p (TREE_OPERAND (name, 0),
2070 TREE_OPERAND (name, 1)))
2071 /* If NAME is "T::X" where "T" is dependent, then the
2072 expression is dependent. */
2073 || (TREE_CODE (name) == SCOPE_REF
2074 && TYPE_P (TREE_OPERAND (name, 0))
2075 && dependent_type_p (TREE_OPERAND (name, 0))))
2076 return build_min_nt (COMPONENT_REF, object, name, NULL_TREE);
2077 object = build_non_dependent_expr (object);
2082 The type of the first expression shall be "class object" (of a
2084 if (!currently_open_class (object_type)
2085 && !complete_type_or_else (object_type, object))
2086 return error_mark_node;
2087 if (!CLASS_TYPE_P (object_type))
2089 error ("request for member %qD in %qE, which is of non-class type %qT",
2090 name, object, object_type);
2091 return error_mark_node;
2094 if (BASELINK_P (name))
2095 /* A member function that has already been looked up. */
2099 bool is_template_id = false;
2100 tree template_args = NULL_TREE;
2103 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
2105 is_template_id = true;
2106 template_args = TREE_OPERAND (name, 1);
2107 name = TREE_OPERAND (name, 0);
2109 if (TREE_CODE (name) == OVERLOAD)
2110 name = DECL_NAME (get_first_fn (name));
2111 else if (DECL_P (name))
2112 name = DECL_NAME (name);
2115 if (TREE_CODE (name) == SCOPE_REF)
2117 /* A qualified name. The qualifying class or namespace `S'
2118 has already been looked up; it is either a TYPE or a
2120 scope = TREE_OPERAND (name, 0);
2121 name = TREE_OPERAND (name, 1);
2123 /* If SCOPE is a namespace, then the qualified name does not
2124 name a member of OBJECT_TYPE. */
2125 if (TREE_CODE (scope) == NAMESPACE_DECL)
2127 error ("%<%D::%D%> is not a member of %qT",
2128 scope, name, object_type);
2129 return error_mark_node;
2132 gcc_assert (CLASS_TYPE_P (scope));
2133 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE
2134 || TREE_CODE (name) == BIT_NOT_EXPR);
2136 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
2137 access_path = lookup_base (object_type, scope, ba_check, NULL);
2138 if (access_path == error_mark_node)
2139 return error_mark_node;
2142 error ("%qT is not a base of %qT", scope, object_type);
2143 return error_mark_node;
2149 access_path = object_type;
2152 if (TREE_CODE (name) == BIT_NOT_EXPR)
2153 member = lookup_destructor (object, scope, name);
2156 /* Look up the member. */
2157 member = lookup_member (access_path, name, /*protect=*/1,
2158 /*want_type=*/false);
2159 if (member == NULL_TREE)
2161 error ("%qD has no member named %qE", object_type, name);
2162 return error_mark_node;
2164 if (member == error_mark_node)
2165 return error_mark_node;
2170 tree template = member;
2172 if (BASELINK_P (template))
2173 template = lookup_template_function (template, template_args);
2176 error ("%qD is not a member template function", name);
2177 return error_mark_node;
2182 if (TREE_DEPRECATED (member))
2183 warn_deprecated_use (member);
2186 check_template_keyword (member);
2188 expr = build_class_member_access_expr (object, member, access_path,
2189 /*preserve_reference=*/false);
2190 if (processing_template_decl && expr != error_mark_node)
2192 if (BASELINK_P (member))
2194 if (TREE_CODE (orig_name) == SCOPE_REF)
2195 BASELINK_QUALIFIED_P (member) = 1;
2198 return build_min_non_dep (COMPONENT_REF, expr,
2199 orig_object, orig_name,
2206 /* Return an expression for the MEMBER_NAME field in the internal
2207 representation of PTRMEM, a pointer-to-member function. (Each
2208 pointer-to-member function type gets its own RECORD_TYPE so it is
2209 more convenient to access the fields by name than by FIELD_DECL.)
2210 This routine converts the NAME to a FIELD_DECL and then creates the
2211 node for the complete expression. */
2214 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2220 /* This code is a stripped down version of
2221 build_class_member_access_expr. It does not work to use that
2222 routine directly because it expects the object to be of class
2224 ptrmem_type = TREE_TYPE (ptrmem);
2225 gcc_assert (TYPE_PTRMEMFUNC_P (ptrmem_type));
2226 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2227 /*want_type=*/false);
2228 member_type = cp_build_qualified_type (TREE_TYPE (member),
2229 cp_type_quals (ptrmem_type));
2230 return fold_build3 (COMPONENT_REF, member_type,
2231 ptrmem, member, NULL_TREE);
2234 /* Given an expression PTR for a pointer, return an expression
2235 for the value pointed to.
2236 ERRORSTRING is the name of the operator to appear in error messages.
2238 This function may need to overload OPERATOR_FNNAME.
2239 Must also handle REFERENCE_TYPEs for C++. */
2242 build_x_indirect_ref (tree expr, const char *errorstring)
2244 tree orig_expr = expr;
2247 if (processing_template_decl)
2249 if (type_dependent_expression_p (expr))
2250 return build_min_nt (INDIRECT_REF, expr);
2251 expr = build_non_dependent_expr (expr);
2254 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2255 NULL_TREE, /*overloaded_p=*/NULL);
2257 rval = build_indirect_ref (expr, errorstring);
2259 if (processing_template_decl && rval != error_mark_node)
2260 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2266 build_indirect_ref (tree ptr, const char *errorstring)
2270 if (ptr == error_mark_node)
2271 return error_mark_node;
2273 if (ptr == current_class_ptr)
2274 return current_class_ref;
2276 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2277 ? ptr : decay_conversion (ptr));
2278 type = TREE_TYPE (pointer);
2280 if (POINTER_TYPE_P (type))
2284 If the type of the expression is "pointer to T," the type
2285 of the result is "T."
2287 We must use the canonical variant because certain parts of
2288 the back end, like fold, do pointer comparisons between
2290 tree t = canonical_type_variant (TREE_TYPE (type));
2292 if (VOID_TYPE_P (t))
2294 /* A pointer to incomplete type (other than cv void) can be
2295 dereferenced [expr.unary.op]/1 */
2296 error ("%qT is not a pointer-to-object type", type);
2297 return error_mark_node;
2299 else if (TREE_CODE (pointer) == ADDR_EXPR
2300 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2301 /* The POINTER was something like `&x'. We simplify `*&x' to
2303 return TREE_OPERAND (pointer, 0);
2306 tree ref = build1 (INDIRECT_REF, t, pointer);
2308 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2309 so that we get the proper error message if the result is used
2310 to assign to. Also, &* is supposed to be a no-op. */
2311 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2312 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2313 TREE_SIDE_EFFECTS (ref)
2314 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2318 /* `pointer' won't be an error_mark_node if we were given a
2319 pointer to member, so it's cool to check for this here. */
2320 else if (TYPE_PTR_TO_MEMBER_P (type))
2321 error ("invalid use of %qs on pointer to member", errorstring);
2322 else if (pointer != error_mark_node)
2325 error ("invalid type argument of %qs", errorstring);
2327 error ("invalid type argument");
2329 return error_mark_node;
2332 /* This handles expressions of the form "a[i]", which denotes
2335 This is logically equivalent in C to *(a+i), but we may do it differently.
2336 If A is a variable or a member, we generate a primitive ARRAY_REF.
2337 This avoids forcing the array out of registers, and can work on
2338 arrays that are not lvalues (for example, members of structures returned
2341 If INDEX is of some user-defined type, it must be converted to
2342 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2343 will inherit the type of the array, which will be some pointer type. */
2346 build_array_ref (tree array, tree idx)
2350 error ("subscript missing in array reference");
2351 return error_mark_node;
2354 if (TREE_TYPE (array) == error_mark_node
2355 || TREE_TYPE (idx) == error_mark_node)
2356 return error_mark_node;
2358 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2360 switch (TREE_CODE (array))
2364 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2365 return build2 (COMPOUND_EXPR, TREE_TYPE (value),
2366 TREE_OPERAND (array, 0), value);
2370 return build_conditional_expr
2371 (TREE_OPERAND (array, 0),
2372 build_array_ref (TREE_OPERAND (array, 1), idx),
2373 build_array_ref (TREE_OPERAND (array, 2), idx));
2379 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2383 warn_array_subscript_with_type_char (idx);
2385 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2387 error ("array subscript is not an integer");
2388 return error_mark_node;
2391 /* Apply integral promotions *after* noticing character types.
2392 (It is unclear why we do these promotions -- the standard
2393 does not say that we should. In fact, the natural thing would
2394 seem to be to convert IDX to ptrdiff_t; we're performing
2395 pointer arithmetic.) */
2396 idx = perform_integral_promotions (idx);
2398 /* An array that is indexed by a non-constant
2399 cannot be stored in a register; we must be able to do
2400 address arithmetic on its address.
2401 Likewise an array of elements of variable size. */
2402 if (TREE_CODE (idx) != INTEGER_CST
2403 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2404 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2407 if (!cxx_mark_addressable (array))
2408 return error_mark_node;
2411 /* An array that is indexed by a constant value which is not within
2412 the array bounds cannot be stored in a register either; because we
2413 would get a crash in store_bit_field/extract_bit_field when trying
2414 to access a non-existent part of the register. */
2415 if (TREE_CODE (idx) == INTEGER_CST
2416 && TYPE_DOMAIN (TREE_TYPE (array))
2417 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2419 if (!cxx_mark_addressable (array))
2420 return error_mark_node;
2423 if (pedantic && !lvalue_p (array))
2424 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2426 /* Note in C++ it is valid to subscript a `register' array, since
2427 it is valid to take the address of something with that
2428 storage specification. */
2432 while (TREE_CODE (foo) == COMPONENT_REF)
2433 foo = TREE_OPERAND (foo, 0);
2434 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2435 warning (OPT_Wextra, "subscripting array declared %<register%>");
2438 type = TREE_TYPE (TREE_TYPE (array));
2439 rval = build4 (ARRAY_REF, type, array, idx, NULL_TREE, NULL_TREE);
2440 /* Array ref is const/volatile if the array elements are
2441 or if the array is.. */
2442 TREE_READONLY (rval)
2443 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2444 TREE_SIDE_EFFECTS (rval)
2445 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2446 TREE_THIS_VOLATILE (rval)
2447 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2448 return require_complete_type (fold_if_not_in_template (rval));
2452 tree ar = default_conversion (array);
2453 tree ind = default_conversion (idx);
2455 /* Put the integer in IND to simplify error checking. */
2456 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2463 if (ar == error_mark_node)
2466 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2468 error ("subscripted value is neither array nor pointer");
2469 return error_mark_node;
2471 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2473 error ("array subscript is not an integer");
2474 return error_mark_node;
2477 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2482 /* Resolve a pointer to member function. INSTANCE is the object
2483 instance to use, if the member points to a virtual member.
2485 This used to avoid checking for virtual functions if basetype
2486 has no virtual functions, according to an earlier ANSI draft.
2487 With the final ISO C++ rules, such an optimization is
2488 incorrect: A pointer to a derived member can be static_cast
2489 to pointer-to-base-member, as long as the dynamic object
2490 later has the right member. */
2493 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2495 if (TREE_CODE (function) == OFFSET_REF)
2496 function = TREE_OPERAND (function, 1);
2498 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2500 tree idx, delta, e1, e2, e3, vtbl, basetype;
2501 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2503 tree instance_ptr = *instance_ptrptr;
2504 tree instance_save_expr = 0;
2505 if (instance_ptr == error_mark_node)
2507 if (TREE_CODE (function) == PTRMEM_CST)
2509 /* Extracting the function address from a pmf is only
2510 allowed with -Wno-pmf-conversions. It only works for
2512 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2513 e1 = convert (fntype, e1);
2518 error ("object missing in use of %qE", function);
2519 return error_mark_node;
2523 if (TREE_SIDE_EFFECTS (instance_ptr))
2524 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2526 if (TREE_SIDE_EFFECTS (function))
2527 function = save_expr (function);
2529 /* Start by extracting all the information from the PMF itself. */
2530 e3 = pfn_from_ptrmemfunc (function);
2531 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2532 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2533 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2535 case ptrmemfunc_vbit_in_pfn:
2536 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2537 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2540 case ptrmemfunc_vbit_in_delta:
2541 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2542 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2549 /* Convert down to the right base before using the instance. A
2550 special case is that in a pointer to member of class C, C may
2551 be incomplete. In that case, the function will of course be
2552 a member of C, and no conversion is required. In fact,
2553 lookup_base will fail in that case, because incomplete
2554 classes do not have BINFOs. */
2555 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2556 if (!same_type_ignoring_top_level_qualifiers_p
2557 (basetype, TREE_TYPE (TREE_TYPE (instance_ptr))))
2559 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2560 basetype, ba_check, NULL);
2561 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype,
2563 if (instance_ptr == error_mark_node)
2564 return error_mark_node;
2566 /* ...and then the delta in the PMF. */
2567 instance_ptr = build2 (PLUS_EXPR, TREE_TYPE (instance_ptr),
2568 instance_ptr, delta);
2570 /* Hand back the adjusted 'this' argument to our caller. */
2571 *instance_ptrptr = instance_ptr;
2573 /* Next extract the vtable pointer from the object. */
2574 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2576 vtbl = build_indirect_ref (vtbl, NULL);
2578 /* Finally, extract the function pointer from the vtable. */
2579 e2 = fold_build2 (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx);
2580 e2 = build_indirect_ref (e2, NULL);
2581 TREE_CONSTANT (e2) = 1;
2582 TREE_INVARIANT (e2) = 1;
2584 /* When using function descriptors, the address of the
2585 vtable entry is treated as a function pointer. */
2586 if (TARGET_VTABLE_USES_DESCRIPTORS)
2587 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2588 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2590 TREE_TYPE (e2) = TREE_TYPE (e3);
2591 e1 = build_conditional_expr (e1, e2, e3);
2593 /* Make sure this doesn't get evaluated first inside one of the
2594 branches of the COND_EXPR. */
2595 if (instance_save_expr)
2596 e1 = build2 (COMPOUND_EXPR, TREE_TYPE (e1),
2597 instance_save_expr, e1);
2605 build_function_call (tree function, tree params)
2607 tree fntype, fndecl;
2608 tree coerced_params;
2609 tree name = NULL_TREE;
2611 tree original = function;
2613 /* For Objective-C, convert any calls via a cast to OBJC_TYPE_REF
2614 expressions, like those used for ObjC messenger dispatches. */
2615 function = objc_rewrite_function_call (function, params);
2617 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2618 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2619 if (TREE_CODE (function) == NOP_EXPR
2620 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2621 function = TREE_OPERAND (function, 0);
2623 if (TREE_CODE (function) == FUNCTION_DECL)
2625 name = DECL_NAME (function);
2627 mark_used (function);
2630 /* Convert anything with function type to a pointer-to-function. */
2631 if (pedantic && DECL_MAIN_P (function))
2632 pedwarn ("ISO C++ forbids calling %<::main%> from within program");
2634 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2635 (because calling an inline function does not mean the function
2636 needs to be separately compiled). */
2638 if (DECL_INLINE (function))
2639 function = inline_conversion (function);
2641 function = build_addr_func (function);
2647 function = build_addr_func (function);
2650 if (function == error_mark_node)
2651 return error_mark_node;
2653 fntype = TREE_TYPE (function);
2655 if (TYPE_PTRMEMFUNC_P (fntype))
2657 error ("must use %<.*%> or %<->*%> to call pointer-to-member "
2658 "function in %<%E (...)%>",
2660 return error_mark_node;
2663 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2664 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2666 if (!((TREE_CODE (fntype) == POINTER_TYPE
2667 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2669 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2671 error ("%qE cannot be used as a function", original);
2672 return error_mark_node;
2675 /* fntype now gets the type of function pointed to. */
2676 fntype = TREE_TYPE (fntype);
2678 /* Convert the parameters to the types declared in the
2679 function prototype, or apply default promotions. */
2681 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2682 params, fndecl, LOOKUP_NORMAL);
2683 if (coerced_params == error_mark_node)
2684 return error_mark_node;
2686 /* Check for errors in format strings and inappropriately
2689 check_function_arguments (TYPE_ATTRIBUTES (fntype), coerced_params,
2690 TYPE_ARG_TYPES (fntype));
2692 return build_cxx_call (function, coerced_params);
2695 /* Convert the actual parameter expressions in the list VALUES
2696 to the types in the list TYPELIST.
2697 If parmdecls is exhausted, or when an element has NULL as its type,
2698 perform the default conversions.
2700 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2702 This is also where warnings about wrong number of args are generated.
2704 Return a list of expressions for the parameters as converted.
2706 Both VALUES and the returned value are chains of TREE_LIST nodes
2707 with the elements of the list in the TREE_VALUE slots of those nodes.
2709 In C++, unspecified trailing parameters can be filled in with their
2710 default arguments, if such were specified. Do so here. */
2713 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2715 tree typetail, valtail;
2716 tree result = NULL_TREE;
2717 const char *called_thing = 0;
2720 /* Argument passing is always copy-initialization. */
2721 flags |= LOOKUP_ONLYCONVERTING;
2725 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2727 if (DECL_NAME (fndecl) == NULL_TREE
2728 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2729 called_thing = "constructor";
2731 called_thing = "member function";
2734 called_thing = "function";
2737 for (valtail = values, typetail = typelist;
2739 valtail = TREE_CHAIN (valtail), i++)
2741 tree type = typetail ? TREE_VALUE (typetail) : 0;
2742 tree val = TREE_VALUE (valtail);
2744 if (val == error_mark_node || type == error_mark_node)
2745 return error_mark_node;
2747 if (type == void_type_node)
2751 error ("too many arguments to %s %q+#D", called_thing, fndecl);
2752 error ("at this point in file");
2755 error ("too many arguments to function");
2756 /* In case anybody wants to know if this argument
2759 TREE_TYPE (tree_last (result)) = error_mark_node;
2763 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2764 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2765 if (TREE_CODE (val) == NOP_EXPR
2766 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2767 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2768 val = TREE_OPERAND (val, 0);
2770 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2772 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2773 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2774 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2775 val = decay_conversion (val);
2778 if (val == error_mark_node)
2779 return error_mark_node;
2783 /* Formal parm type is specified by a function prototype. */
2786 if (!COMPLETE_TYPE_P (complete_type (type)))
2789 error ("parameter %P of %qD has incomplete type %qT",
2792 error ("parameter %P has incomplete type %qT", i, type);
2793 parmval = error_mark_node;
2797 parmval = convert_for_initialization
2798 (NULL_TREE, type, val, flags,
2799 "argument passing", fndecl, i);
2800 parmval = convert_for_arg_passing (type, parmval);
2803 if (parmval == error_mark_node)
2804 return error_mark_node;
2806 result = tree_cons (NULL_TREE, parmval, result);
2810 if (fndecl && DECL_BUILT_IN (fndecl)
2811 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2812 /* Don't do ellipsis conversion for __built_in_constant_p
2813 as this will result in spurious warnings for non-POD
2815 val = require_complete_type (val);
2817 val = convert_arg_to_ellipsis (val);
2819 result = tree_cons (NULL_TREE, val, result);
2823 typetail = TREE_CHAIN (typetail);
2826 if (typetail != 0 && typetail != void_list_node)
2828 /* See if there are default arguments that can be used. */
2829 if (TREE_PURPOSE (typetail)
2830 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2832 for (; typetail != void_list_node; ++i)
2835 = convert_default_arg (TREE_VALUE (typetail),
2836 TREE_PURPOSE (typetail),
2839 if (parmval == error_mark_node)
2840 return error_mark_node;
2842 result = tree_cons (0, parmval, result);
2843 typetail = TREE_CHAIN (typetail);
2844 /* ends with `...'. */
2845 if (typetail == NULL_TREE)
2853 error ("too few arguments to %s %q+#D", called_thing, fndecl);
2854 error ("at this point in file");
2857 error ("too few arguments to function");
2858 return error_mark_node;
2862 return nreverse (result);
2865 /* Build a binary-operation expression, after performing default
2866 conversions on the operands. CODE is the kind of expression to build. */
2869 build_x_binary_op (enum tree_code code, tree arg1, tree arg2,
2879 if (processing_template_decl)
2881 if (type_dependent_expression_p (arg1)
2882 || type_dependent_expression_p (arg2))
2883 return build_min_nt (code, arg1, arg2);
2884 arg1 = build_non_dependent_expr (arg1);
2885 arg2 = build_non_dependent_expr (arg2);
2888 if (code == DOTSTAR_EXPR)
2889 expr = build_m_component_ref (arg1, arg2);
2891 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
2894 if (processing_template_decl && expr != error_mark_node)
2895 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
2900 /* Build a binary-operation expression without default conversions.
2901 CODE is the kind of expression to build.
2902 This function differs from `build' in several ways:
2903 the data type of the result is computed and recorded in it,
2904 warnings are generated if arg data types are invalid,
2905 special handling for addition and subtraction of pointers is known,
2906 and some optimization is done (operations on narrow ints
2907 are done in the narrower type when that gives the same result).
2908 Constant folding is also done before the result is returned.
2910 Note that the operands will never have enumeral types
2911 because either they have just had the default conversions performed
2912 or they have both just been converted to some other type in which
2913 the arithmetic is to be done.
2915 C++: must do special pointer arithmetic when implementing
2916 multiple inheritance, and deal with pointer to member functions. */
2919 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2920 int convert_p ATTRIBUTE_UNUSED)
2923 enum tree_code code0, code1;
2925 const char *invalid_op_diag;
2927 /* Expression code to give to the expression when it is built.
2928 Normally this is CODE, which is what the caller asked for,
2929 but in some special cases we change it. */
2930 enum tree_code resultcode = code;
2932 /* Data type in which the computation is to be performed.
2933 In the simplest cases this is the common type of the arguments. */
2934 tree result_type = NULL;
2936 /* Nonzero means operands have already been type-converted
2937 in whatever way is necessary.
2938 Zero means they need to be converted to RESULT_TYPE. */
2941 /* Nonzero means create the expression with this type, rather than
2943 tree build_type = 0;
2945 /* Nonzero means after finally constructing the expression
2946 convert it to this type. */
2947 tree final_type = 0;
2951 /* Nonzero if this is an operation like MIN or MAX which can
2952 safely be computed in short if both args are promoted shorts.
2953 Also implies COMMON.
2954 -1 indicates a bitwise operation; this makes a difference
2955 in the exact conditions for when it is safe to do the operation
2956 in a narrower mode. */
2959 /* Nonzero if this is a comparison operation;
2960 if both args are promoted shorts, compare the original shorts.
2961 Also implies COMMON. */
2962 int short_compare = 0;
2964 /* Nonzero if this is a right-shift operation, which can be computed on the
2965 original short and then promoted if the operand is a promoted short. */
2966 int short_shift = 0;
2968 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2971 /* True if both operands have arithmetic type. */
2972 bool arithmetic_types_p;
2974 /* Apply default conversions. */
2978 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2979 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2980 || code == TRUTH_XOR_EXPR)
2982 if (!really_overloaded_fn (op0))
2983 op0 = decay_conversion (op0);
2984 if (!really_overloaded_fn (op1))
2985 op1 = decay_conversion (op1);
2989 if (!really_overloaded_fn (op0))
2990 op0 = default_conversion (op0);
2991 if (!really_overloaded_fn (op1))
2992 op1 = default_conversion (op1);
2995 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2996 STRIP_TYPE_NOPS (op0);
2997 STRIP_TYPE_NOPS (op1);
2999 /* DTRT if one side is an overloaded function, but complain about it. */
3000 if (type_unknown_p (op0))
3002 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
3003 if (t != error_mark_node)
3005 pedwarn ("assuming cast to type %qT from overloaded function",
3010 if (type_unknown_p (op1))
3012 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
3013 if (t != error_mark_node)
3015 pedwarn ("assuming cast to type %qT from overloaded function",
3021 type0 = TREE_TYPE (op0);
3022 type1 = TREE_TYPE (op1);
3024 /* The expression codes of the data types of the arguments tell us
3025 whether the arguments are integers, floating, pointers, etc. */
3026 code0 = TREE_CODE (type0);
3027 code1 = TREE_CODE (type1);
3029 /* If an error was already reported for one of the arguments,
3030 avoid reporting another error. */
3032 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
3033 return error_mark_node;
3035 if ((invalid_op_diag
3036 = targetm.invalid_binary_op (code, type0, type1)))
3038 error (invalid_op_diag);
3039 return error_mark_node;
3045 /* Handle the pointer + int case. */
3046 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3047 return cp_pointer_int_sum (PLUS_EXPR, op0, op1);
3048 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
3049 return cp_pointer_int_sum (PLUS_EXPR, op1, op0);
3055 /* Subtraction of two similar pointers.
3056 We must subtract them as integers, then divide by object size. */
3057 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
3058 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
3060 return pointer_diff (op0, op1, common_type (type0, type1));
3061 /* Handle pointer minus int. Just like pointer plus int. */
3062 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3063 return cp_pointer_int_sum (MINUS_EXPR, op0, op1);
3072 case TRUNC_DIV_EXPR:
3074 case FLOOR_DIV_EXPR:
3075 case ROUND_DIV_EXPR:
3076 case EXACT_DIV_EXPR:
3077 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3078 || code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3079 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3080 || code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE))
3082 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
3083 warning (OPT_Wdiv_by_zero, "division by zero in %<%E / 0%>", op0);
3084 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
3085 warning (OPT_Wdiv_by_zero, "division by zero in %<%E / 0.%>", op0);
3087 if (code0 == COMPLEX_TYPE || code0 == VECTOR_TYPE)
3088 code0 = TREE_CODE (TREE_TYPE (TREE_TYPE (op0)));
3089 if (code1 == COMPLEX_TYPE || code1 == VECTOR_TYPE)
3090 code1 = TREE_CODE (TREE_TYPE (TREE_TYPE (op1)));
3092 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
3093 resultcode = RDIV_EXPR;
3095 /* When dividing two signed integers, we have to promote to int.
3096 unless we divide by a constant != -1. Note that default
3097 conversion will have been performed on the operands at this
3098 point, so we have to dig out the original type to find out if
3100 shorten = ((TREE_CODE (op0) == NOP_EXPR
3101 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3102 || (TREE_CODE (op1) == INTEGER_CST
3103 && ! integer_all_onesp (op1)));
3112 if ((code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3113 || (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE))
3117 case TRUNC_MOD_EXPR:
3118 case FLOOR_MOD_EXPR:
3119 if (code1 == INTEGER_TYPE && integer_zerop (op1))
3120 warning (OPT_Wdiv_by_zero, "division by zero in %<%E %% 0%>", op0);
3121 else if (code1 == REAL_TYPE && real_zerop (op1))
3122 warning (OPT_Wdiv_by_zero, "division by zero in %<%E %% 0.%>", op0);
3124 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3126 /* Although it would be tempting to shorten always here, that loses
3127 on some targets, since the modulo instruction is undefined if the
3128 quotient can't be represented in the computation mode. We shorten
3129 only if unsigned or if dividing by something we know != -1. */
3130 shorten = ((TREE_CODE (op0) == NOP_EXPR
3131 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
3132 || (TREE_CODE (op1) == INTEGER_CST
3133 && ! integer_all_onesp (op1)));
3138 case TRUTH_ANDIF_EXPR:
3139 case TRUTH_ORIF_EXPR:
3140 case TRUTH_AND_EXPR:
3142 result_type = boolean_type_node;
3145 /* Shift operations: result has same type as first operand;
3146 always convert second operand to int.
3147 Also set SHORT_SHIFT if shifting rightward. */
3150 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3152 result_type = type0;
3153 if (TREE_CODE (op1) == INTEGER_CST)
3155 if (tree_int_cst_lt (op1, integer_zero_node))
3156 warning (0, "right shift count is negative");
3159 if (! integer_zerop (op1))
3161 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3162 warning (0, "right shift count >= width of type");
3165 /* Convert the shift-count to an integer, regardless of
3166 size of value being shifted. */
3167 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3168 op1 = cp_convert (integer_type_node, op1);
3169 /* Avoid converting op1 to result_type later. */
3175 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3177 result_type = type0;
3178 if (TREE_CODE (op1) == INTEGER_CST)
3180 if (tree_int_cst_lt (op1, integer_zero_node))
3181 warning (0, "left shift count is negative");
3182 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3183 warning (0, "left shift count >= width of type");
3185 /* Convert the shift-count to an integer, regardless of
3186 size of value being shifted. */
3187 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3188 op1 = cp_convert (integer_type_node, op1);
3189 /* Avoid converting op1 to result_type later. */
3196 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
3198 result_type = type0;
3199 if (TREE_CODE (op1) == INTEGER_CST)
3201 if (tree_int_cst_lt (op1, integer_zero_node))
3202 warning (0, "%s rotate count is negative",
3203 (code == LROTATE_EXPR) ? "left" : "right");
3204 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
3205 warning (0, "%s rotate count >= width of type",
3206 (code == LROTATE_EXPR) ? "left" : "right");
3208 /* Convert the shift-count to an integer, regardless of
3209 size of value being shifted. */
3210 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
3211 op1 = cp_convert (integer_type_node, op1);
3217 if (code0 == REAL_TYPE || code1 == REAL_TYPE)
3218 warning (OPT_Wfloat_equal,
3219 "comparing floating point with == or != is unsafe");
3220 if ((TREE_CODE (orig_op0) == STRING_CST && !integer_zerop (op1))
3221 || (TREE_CODE (orig_op1) == STRING_CST && !integer_zerop (op0)))
3222 warning (OPT_Wstring_literal_comparison,
3223 "comparison with string literal");
3225 build_type = boolean_type_node;
3226 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3227 || code0 == COMPLEX_TYPE)
3228 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3229 || code1 == COMPLEX_TYPE))
3231 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3232 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3233 result_type = composite_pointer_type (type0, type1, op0, op1,
3235 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3236 && null_ptr_cst_p (op1))
3237 result_type = type0;
3238 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3239 && null_ptr_cst_p (op0))
3240 result_type = type1;
3241 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3243 result_type = type0;
3244 error ("ISO C++ forbids comparison between pointer and integer");
3246 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3248 result_type = type1;
3249 error ("ISO C++ forbids comparison between pointer and integer");
3251 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3253 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3254 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3255 result_type = TREE_TYPE (op0);
3257 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3258 return cp_build_binary_op (code, op1, op0);
3259 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
3260 && same_type_p (type0, type1))
3262 /* E will be the final comparison. */
3264 /* E1 and E2 are for scratch. */
3272 if (TREE_SIDE_EFFECTS (op0))
3273 op0 = save_expr (op0);
3274 if (TREE_SIDE_EFFECTS (op1))
3275 op1 = save_expr (op1);
3280 && (!op0.pfn || op0.delta == op1.delta))
3282 The reason for the `!op0.pfn' bit is that a NULL
3283 pointer-to-member is any member with a zero PFN; the
3284 DELTA field is unspecified. */
3285 pfn0 = pfn_from_ptrmemfunc (op0);
3286 pfn1 = pfn_from_ptrmemfunc (op1);
3287 delta0 = build_ptrmemfunc_access_expr (op0,
3289 delta1 = build_ptrmemfunc_access_expr (op1,
3291 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
3292 e2 = cp_build_binary_op (EQ_EXPR,
3294 cp_convert (TREE_TYPE (pfn0),
3295 integer_zero_node));
3296 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
3297 e2 = build2 (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3298 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3299 if (code == EQ_EXPR)
3301 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3305 gcc_assert (!TYPE_PTRMEMFUNC_P (type0)
3306 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0),
3308 gcc_assert (!TYPE_PTRMEMFUNC_P (type1)
3309 || !same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1),
3317 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3318 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3320 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3321 result_type = composite_pointer_type (type0, type1, op0, op1,
3329 if (TREE_CODE (orig_op0) == STRING_CST
3330 || TREE_CODE (orig_op1) == STRING_CST)
3331 warning (OPT_Wstring_literal_comparison,
3332 "comparison with string literal");
3334 build_type = boolean_type_node;
3335 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3336 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3338 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3339 result_type = composite_pointer_type (type0, type1, op0, op1,
3341 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3342 && integer_zerop (op1))
3343 result_type = type0;
3344 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3345 && integer_zerop (op0))
3346 result_type = type1;
3347 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3349 result_type = type0;
3350 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3352 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3354 result_type = type1;
3355 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3359 case UNORDERED_EXPR:
3366 build_type = integer_type_node;
3367 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3369 error ("unordered comparison on non-floating point argument");
3370 return error_mark_node;
3379 if (((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3380 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3381 || code1 == COMPLEX_TYPE)))
3382 arithmetic_types_p = 1;
3385 arithmetic_types_p = 0;
3386 /* Vector arithmetic is only allowed when both sides are vectors. */
3387 if (code0 == VECTOR_TYPE && code1 == VECTOR_TYPE)
3389 if (!tree_int_cst_equal (TYPE_SIZE (type0), TYPE_SIZE (type1))
3390 || !same_scalar_type_ignoring_signedness (TREE_TYPE (type0),
3393 binary_op_error (code);
3394 return error_mark_node;
3396 arithmetic_types_p = 1;
3399 /* Determine the RESULT_TYPE, if it is not already known. */
3401 && arithmetic_types_p
3402 && (shorten || common || short_compare))
3403 result_type = common_type (type0, type1);
3407 error ("invalid operands of types %qT and %qT to binary %qO",
3408 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3409 return error_mark_node;
3412 /* If we're in a template, the only thing we need to know is the
3414 if (processing_template_decl)
3415 return build2 (resultcode,
3416 build_type ? build_type : result_type,
3419 if (arithmetic_types_p)
3421 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3423 /* For certain operations (which identify themselves by shorten != 0)
3424 if both args were extended from the same smaller type,
3425 do the arithmetic in that type and then extend.
3427 shorten !=0 and !=1 indicates a bitwise operation.
3428 For them, this optimization is safe only if
3429 both args are zero-extended or both are sign-extended.
3430 Otherwise, we might change the result.
3431 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3432 but calculated in (unsigned short) it would be (unsigned short)-1. */
3434 if (shorten && none_complex)
3436 int unsigned0, unsigned1;
3437 tree arg0 = get_narrower (op0, &unsigned0);
3438 tree arg1 = get_narrower (op1, &unsigned1);
3439 /* UNS is 1 if the operation to be done is an unsigned one. */
3440 int uns = TYPE_UNSIGNED (result_type);
3443 final_type = result_type;
3445 /* Handle the case that OP0 does not *contain* a conversion
3446 but it *requires* conversion to FINAL_TYPE. */
3448 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3449 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
3450 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3451 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
3453 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3455 /* For bitwise operations, signedness of nominal type
3456 does not matter. Consider only how operands were extended. */
3460 /* Note that in all three cases below we refrain from optimizing
3461 an unsigned operation on sign-extended args.
3462 That would not be valid. */
3464 /* Both args variable: if both extended in same way
3465 from same width, do it in that width.
3466 Do it unsigned if args were zero-extended. */
3467 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3468 < TYPE_PRECISION (result_type))
3469 && (TYPE_PRECISION (TREE_TYPE (arg1))
3470 == TYPE_PRECISION (TREE_TYPE (arg0)))
3471 && unsigned0 == unsigned1
3472 && (unsigned0 || !uns))
3473 result_type = c_common_signed_or_unsigned_type
3474 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3475 else if (TREE_CODE (arg0) == INTEGER_CST
3476 && (unsigned1 || !uns)
3477 && (TYPE_PRECISION (TREE_TYPE (arg1))
3478 < TYPE_PRECISION (result_type))
3479 && (type = c_common_signed_or_unsigned_type
3480 (unsigned1, TREE_TYPE (arg1)),
3481 int_fits_type_p (arg0, type)))
3483 else if (TREE_CODE (arg1) == INTEGER_CST
3484 && (unsigned0 || !uns)
3485 && (TYPE_PRECISION (TREE_TYPE (arg0))
3486 < TYPE_PRECISION (result_type))
3487 && (type = c_common_signed_or_unsigned_type
3488 (unsigned0, TREE_TYPE (arg0)),
3489 int_fits_type_p (arg1, type)))
3493 /* Shifts can be shortened if shifting right. */
3498 tree arg0 = get_narrower (op0, &unsigned_arg);
3500 final_type = result_type;
3502 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3503 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
3505 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3506 /* We can shorten only if the shift count is less than the
3507 number of bits in the smaller type size. */
3508 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3509 /* If arg is sign-extended and then unsigned-shifted,
3510 we can simulate this with a signed shift in arg's type
3511 only if the extended result is at least twice as wide
3512 as the arg. Otherwise, the shift could use up all the
3513 ones made by sign-extension and bring in zeros.
3514 We can't optimize that case at all, but in most machines
3515 it never happens because available widths are 2**N. */
3516 && (!TYPE_UNSIGNED (final_type)
3518 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3519 <= TYPE_PRECISION (result_type))))
3521 /* Do an unsigned shift if the operand was zero-extended. */
3523 = c_common_signed_or_unsigned_type (unsigned_arg,
3525 /* Convert value-to-be-shifted to that type. */
3526 if (TREE_TYPE (op0) != result_type)
3527 op0 = cp_convert (result_type, op0);
3532 /* Comparison operations are shortened too but differently.
3533 They identify themselves by setting short_compare = 1. */
3537 /* Don't write &op0, etc., because that would prevent op0
3538 from being kept in a register.
3539 Instead, make copies of the our local variables and
3540 pass the copies by reference, then copy them back afterward. */
3541 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3542 enum tree_code xresultcode = resultcode;
3544 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3546 return cp_convert (boolean_type_node, val);
3547 op0 = xop0, op1 = xop1;
3549 resultcode = xresultcode;
3552 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3553 && warn_sign_compare
3554 /* Do not warn until the template is instantiated; we cannot
3555 bound the ranges of the arguments until that point. */
3556 && !processing_template_decl)
3558 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
3559 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3561 int unsignedp0, unsignedp1;
3562 tree primop0 = get_narrower (op0, &unsignedp0);
3563 tree primop1 = get_narrower (op1, &unsignedp1);
3565 /* Check for comparison of different enum types. */
3566 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3567 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3568 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3569 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3571 warning (0, "comparison between types %q#T and %q#T",
3572 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3575 /* Give warnings for comparisons between signed and unsigned
3576 quantities that may fail. */
3577 /* Do the checking based on the original operand trees, so that
3578 casts will be considered, but default promotions won't be. */
3580 /* Do not warn if the comparison is being done in a signed type,
3581 since the signed type will only be chosen if it can represent
3582 all the values of the unsigned type. */
3583 if (!TYPE_UNSIGNED (result_type))
3585 /* Do not warn if both operands are unsigned. */
3586 else if (op0_signed == op1_signed)
3588 /* Do not warn if the signed quantity is an unsuffixed
3589 integer literal (or some static constant expression
3590 involving such literals or a conditional expression
3591 involving such literals) and it is non-negative. */
3592 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3593 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3595 /* Do not warn if the comparison is an equality operation,
3596 the unsigned quantity is an integral constant and it does
3597 not use the most significant bit of result_type. */
3598 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3599 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3600 && int_fits_type_p (orig_op1, c_common_signed_type
3602 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3603 && int_fits_type_p (orig_op0, c_common_signed_type
3607 warning (0, "comparison between signed and unsigned integer expressions");
3609 /* Warn if two unsigned values are being compared in a size
3610 larger than their original size, and one (and only one) is the
3611 result of a `~' operator. This comparison will always fail.
3613 Also warn if one operand is a constant, and the constant does not
3614 have all bits set that are set in the ~ operand when it is
3617 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3618 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3620 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3621 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3622 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3623 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3625 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3628 HOST_WIDE_INT constant, mask;
3632 if (host_integerp (primop0, 0))
3635 unsignedp = unsignedp1;
3636 constant = tree_low_cst (primop0, 0);
3641 unsignedp = unsignedp0;
3642 constant = tree_low_cst (primop1, 0);
3645 bits = TYPE_PRECISION (TREE_TYPE (primop));
3646 if (bits < TYPE_PRECISION (result_type)
3647 && bits < HOST_BITS_PER_LONG && unsignedp)
3649 mask = (~ (HOST_WIDE_INT) 0) << bits;
3650 if ((mask & constant) != mask)
3651 warning (0, "comparison of promoted ~unsigned with constant");
3654 else if (unsignedp0 && unsignedp1
3655 && (TYPE_PRECISION (TREE_TYPE (primop0))
3656 < TYPE_PRECISION (result_type))
3657 && (TYPE_PRECISION (TREE_TYPE (primop1))
3658 < TYPE_PRECISION (result_type)))
3659 warning (0, "comparison of promoted ~unsigned with unsigned");
3664 /* If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3665 Then the expression will be built.
3666 It will be given type FINAL_TYPE if that is nonzero;
3667 otherwise, it will be given type RESULT_TYPE. */
3669 /* Issue warnings about peculiar, but valid, uses of NULL. */
3670 if (/* It's reasonable to use pointer values as operands of &&
3671 and ||, so NULL is no exception. */
3672 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3673 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3674 (orig_op0 == null_node
3675 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3676 /* Or vice versa. */
3677 || (orig_op1 == null_node
3678 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3679 /* Or, both are NULL and the operation was not a comparison. */
3680 || (orig_op0 == null_node && orig_op1 == null_node
3681 && code != EQ_EXPR && code != NE_EXPR)))
3682 /* Some sort of arithmetic operation involving NULL was
3683 performed. Note that pointer-difference and pointer-addition
3684 have already been handled above, and so we don't end up here in
3686 warning (0, "NULL used in arithmetic");
3690 if (TREE_TYPE (op0) != result_type)
3691 op0 = cp_convert (result_type, op0);
3692 if (TREE_TYPE (op1) != result_type)
3693 op1 = cp_convert (result_type, op1);
3695 if (op0 == error_mark_node || op1 == error_mark_node)
3696 return error_mark_node;
3699 if (build_type == NULL_TREE)
3700 build_type = result_type;
3702 result = build2 (resultcode, build_type, op0, op1);
3703 result = fold_if_not_in_template (result);
3704 if (final_type != 0)
3705 result = cp_convert (final_type, result);
3709 /* Return a tree for the sum or difference (RESULTCODE says which)
3710 of pointer PTROP and integer INTOP. */
3713 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
3715 tree res_type = TREE_TYPE (ptrop);
3717 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3718 in certain circumstance (when it's valid to do so). So we need
3719 to make sure it's complete. We don't need to check here, if we
3720 can actually complete it at all, as those checks will be done in
3721 pointer_int_sum() anyway. */
3722 complete_type (TREE_TYPE (res_type));
3724 return pointer_int_sum (resultcode, ptrop,
3725 fold_if_not_in_template (intop));
3728 /* Return a tree for the difference of pointers OP0 and OP1.
3729 The resulting tree has type int. */
3732 pointer_diff (tree op0, tree op1, tree ptrtype)
3735 tree restype = ptrdiff_type_node;
3736 tree target_type = TREE_TYPE (ptrtype);
3738 if (!complete_type_or_else (target_type, NULL_TREE))
3739 return error_mark_node;
3741 if (pedantic || warn_pointer_arith)
3743 if (TREE_CODE (target_type) == VOID_TYPE)
3744 pedwarn ("ISO C++ forbids using pointer of type %<void *%> in subtraction");
3745 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3746 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3747 if (TREE_CODE (target_type) == METHOD_TYPE)
3748 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3751 /* First do the subtraction as integers;
3752 then drop through to build the divide operator. */
3754 op0 = cp_build_binary_op (MINUS_EXPR,
3755 cp_convert (restype, op0),
3756 cp_convert (restype, op1));
3758 /* This generates an error if op1 is a pointer to an incomplete type. */
3759 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3760 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3762 op1 = (TYPE_PTROB_P (ptrtype)
3763 ? size_in_bytes (target_type)
3764 : integer_one_node);
3766 /* Do the division. */
3768 result = build2 (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3769 return fold_if_not_in_template (result);
3772 /* Construct and perhaps optimize a tree representation
3773 for a unary operation. CODE, a tree_code, specifies the operation
3774 and XARG is the operand. */
3777 build_x_unary_op (enum tree_code code, tree xarg)
3779 tree orig_expr = xarg;
3783 if (processing_template_decl)
3785 if (type_dependent_expression_p (xarg))
3786 return build_min_nt (code, xarg, NULL_TREE);
3788 xarg = build_non_dependent_expr (xarg);
3793 /* [expr.unary.op] says:
3795 The address of an object of incomplete type can be taken.
3797 (And is just the ordinary address operator, not an overloaded
3798 "operator &".) However, if the type is a template
3799 specialization, we must complete the type at this point so that
3800 an overloaded "operator &" will be available if required. */
3801 if (code == ADDR_EXPR
3802 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3803 && ((CLASS_TYPE_P (TREE_TYPE (xarg))
3804 && !COMPLETE_TYPE_P (complete_type (TREE_TYPE (xarg))))
3805 || (TREE_CODE (xarg) == OFFSET_REF)))
3806 /* Don't look for a function. */;
3808 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
3809 /*overloaded_p=*/NULL);
3810 if (!exp && code == ADDR_EXPR)
3812 /* A pointer to member-function can be formed only by saying
3814 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3815 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3817 if (TREE_CODE (xarg) != OFFSET_REF
3818 || !TYPE_P (TREE_OPERAND (xarg, 0)))
3820 error ("invalid use of %qE to form a pointer-to-member-function",
3822 if (TREE_CODE (xarg) != OFFSET_REF)
3823 inform (" a qualified-id is required");
3824 return error_mark_node;
3828 error ("parentheses around %qE cannot be used to form a"
3829 " pointer-to-member-function",
3831 PTRMEM_OK_P (xarg) = 1;
3835 if (TREE_CODE (xarg) == OFFSET_REF)
3837 ptrmem = PTRMEM_OK_P (xarg);
3839 if (!ptrmem && !flag_ms_extensions
3840 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3842 /* A single non-static member, make sure we don't allow a
3843 pointer-to-member. */
3844 xarg = build2 (OFFSET_REF, TREE_TYPE (xarg),
3845 TREE_OPERAND (xarg, 0),
3846 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3847 PTRMEM_OK_P (xarg) = ptrmem;
3850 else if (TREE_CODE (xarg) == TARGET_EXPR)
3851 warning (0, "taking address of temporary");
3852 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3855 if (processing_template_decl && exp != error_mark_node)
3856 exp = build_min_non_dep (code, exp, orig_expr,
3857 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
3858 if (TREE_CODE (exp) == ADDR_EXPR)
3859 PTRMEM_OK_P (exp) = ptrmem;
3863 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3864 constants, where a null value is represented by an INTEGER_CST of
3868 cp_truthvalue_conversion (tree expr)
3870 tree type = TREE_TYPE (expr);
3871 if (TYPE_PTRMEM_P (type))
3872 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3874 return c_common_truthvalue_conversion (expr);
3877 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3880 condition_conversion (tree expr)
3883 if (processing_template_decl)
3885 t = perform_implicit_conversion (boolean_type_node, expr);
3886 t = fold_build_cleanup_point_expr (boolean_type_node, t);
3890 /* Return an ADDR_EXPR giving the address of T. This function
3891 attempts no optimizations or simplifications; it is a low-level
3895 build_address (tree t)
3899 if (error_operand_p (t) || !cxx_mark_addressable (t))
3900 return error_mark_node;
3902 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
3907 /* Return a NOP_EXPR converting EXPR to TYPE. */
3910 build_nop (tree type, tree expr)
3912 if (type == error_mark_node || error_operand_p (expr))
3914 return build1 (NOP_EXPR, type, expr);
3917 /* C++: Must handle pointers to members.
3919 Perhaps type instantiation should be extended to handle conversion
3920 from aggregates to types we don't yet know we want? (Or are those
3921 cases typically errors which should be reported?)
3923 NOCONVERT nonzero suppresses the default promotions
3924 (such as from short to int). */
3927 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3929 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3932 const char *errstring = NULL;
3934 const char *invalid_op_diag;
3936 if (arg == error_mark_node)
3937 return error_mark_node;
3939 if ((invalid_op_diag
3940 = targetm.invalid_unary_op ((code == UNARY_PLUS_EXPR
3945 error (invalid_op_diag);
3946 return error_mark_node;
3951 case UNARY_PLUS_EXPR:
3954 int flags = WANT_ARITH | WANT_ENUM;
3955 /* Unary plus (but not unary minus) is allowed on pointers. */
3956 if (code == UNARY_PLUS_EXPR)
3957 flags |= WANT_POINTER;
3958 arg = build_expr_type_conversion (flags, arg, true);
3960 errstring = (code == NEGATE_EXPR
3961 ? "wrong type argument to unary minus"
3962 : "wrong type argument to unary plus");
3965 if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3966 arg = perform_integral_promotions (arg);
3968 /* Make sure the result is not an lvalue: a unary plus or minus
3969 expression is always a rvalue. */
3976 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3980 arg = default_conversion (arg);
3982 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
3984 errstring = "wrong type argument to bit-complement";
3985 else if (!noconvert)
3986 arg = perform_integral_promotions (arg);
3990 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3991 errstring = "wrong type argument to abs";
3992 else if (!noconvert)
3993 arg = default_conversion (arg);
3997 /* Conjugating a real value is a no-op, but allow it anyway. */
3998 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3999 errstring = "wrong type argument to conjugation";
4000 else if (!noconvert)
4001 arg = default_conversion (arg);
4004 case TRUTH_NOT_EXPR:
4005 arg = perform_implicit_conversion (boolean_type_node, arg);
4006 val = invert_truthvalue (arg);
4007 if (arg != error_mark_node)
4009 errstring = "in argument to unary !";
4016 if (TREE_CODE (arg) == COMPLEX_CST)
4017 return TREE_REALPART (arg);
4018 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4020 arg = build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4021 return fold_if_not_in_template (arg);
4027 if (TREE_CODE (arg) == COMPLEX_CST)
4028 return TREE_IMAGPART (arg);
4029 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4031 arg = build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg);
4032 return fold_if_not_in_template (arg);
4035 return cp_convert (TREE_TYPE (arg), integer_zero_node);
4037 case PREINCREMENT_EXPR:
4038 case POSTINCREMENT_EXPR:
4039 case PREDECREMENT_EXPR:
4040 case POSTDECREMENT_EXPR:
4041 /* Handle complex lvalues (when permitted)
4042 by reduction to simpler cases. */
4044 val = unary_complex_lvalue (code, arg);
4048 /* Increment or decrement the real part of the value,
4049 and don't change the imaginary part. */
4050 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
4054 arg = stabilize_reference (arg);
4055 real = build_unary_op (REALPART_EXPR, arg, 1);
4056 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
4057 return build2 (COMPLEX_EXPR, TREE_TYPE (arg),
4058 build_unary_op (code, real, 1), imag);
4061 /* Report invalid types. */
4063 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
4066 if (code == PREINCREMENT_EXPR)
4067 errstring ="no pre-increment operator for type";
4068 else if (code == POSTINCREMENT_EXPR)
4069 errstring ="no post-increment operator for type";
4070 else if (code == PREDECREMENT_EXPR)
4071 errstring ="no pre-decrement operator for type";
4073 errstring ="no post-decrement operator for type";
4077 /* Report something read-only. */
4079 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
4080 || TREE_READONLY (arg))
4081 readonly_error (arg, ((code == PREINCREMENT_EXPR
4082 || code == POSTINCREMENT_EXPR)
4083 ? "increment" : "decrement"),
4088 tree result_type = TREE_TYPE (arg);
4090 arg = get_unwidened (arg, 0);
4091 argtype = TREE_TYPE (arg);
4093 /* ARM $5.2.5 last annotation says this should be forbidden. */
4094 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
4095 pedwarn ("ISO C++ forbids %sing an enum",
4096 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
4097 ? "increment" : "decrement");
4099 /* Compute the increment. */
4101 if (TREE_CODE (argtype) == POINTER_TYPE)
4103 tree type = complete_type (TREE_TYPE (argtype));
4105 if (!COMPLETE_OR_VOID_TYPE_P (type))
4106 error ("cannot %s a pointer to incomplete type %qT",
4107 ((code == PREINCREMENT_EXPR
4108 || code == POSTINCREMENT_EXPR)
4109 ? "increment" : "decrement"), TREE_TYPE (argtype));
4110 else if ((pedantic || warn_pointer_arith)
4111 && !TYPE_PTROB_P (argtype))
4112 pedwarn ("ISO C++ forbids %sing a pointer of type %qT",
4113 ((code == PREINCREMENT_EXPR
4114 || code == POSTINCREMENT_EXPR)
4115 ? "increment" : "decrement"), argtype);
4116 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
4119 inc = integer_one_node;
4121 inc = cp_convert (argtype, inc);
4123 /* Handle incrementing a cast-expression. */
4125 switch (TREE_CODE (arg))
4130 case FIX_TRUNC_EXPR:
4131 case FIX_FLOOR_EXPR:
4132 case FIX_ROUND_EXPR:
4135 tree incremented, modify, value, compound;
4136 if (! lvalue_p (arg) && pedantic)
4137 pedwarn ("cast to non-reference type used as lvalue");
4138 arg = stabilize_reference (arg);
4139 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
4142 value = save_expr (arg);
4143 incremented = build2 (((code == PREINCREMENT_EXPR
4144 || code == POSTINCREMENT_EXPR)
4145 ? PLUS_EXPR : MINUS_EXPR),
4146 argtype, value, inc);
4148 modify = build_modify_expr (arg, NOP_EXPR, incremented);
4149 compound = build2 (COMPOUND_EXPR, TREE_TYPE (arg),
4152 /* Eliminate warning about unused result of + or -. */
4153 TREE_NO_WARNING (compound) = 1;
4161 /* Complain about anything else that is not a true lvalue. */
4162 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
4163 || code == POSTINCREMENT_EXPR)
4164 ? lv_increment : lv_decrement)))
4165 return error_mark_node;
4167 /* Forbid using -- on `bool'. */
4168 if (TREE_TYPE (arg) == boolean_type_node)
4170 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
4172 error ("invalid use of %<--%> on bool variable %qD", arg);
4173 return error_mark_node;
4175 val = boolean_increment (code, arg);
4178 val = build2 (code, TREE_TYPE (arg), arg, inc);
4180 TREE_SIDE_EFFECTS (val) = 1;
4181 return cp_convert (result_type, val);
4185 /* Note that this operation never does default_conversion
4186 regardless of NOCONVERT. */
4188 argtype = lvalue_type (arg);
4190 if (TREE_CODE (arg) == OFFSET_REF)
4193 if (TREE_CODE (argtype) == REFERENCE_TYPE)
4195 tree type = build_pointer_type (TREE_TYPE (argtype));
4196 arg = build1 (CONVERT_EXPR, type, arg);
4199 else if (pedantic && DECL_MAIN_P (arg))
4201 pedwarn ("ISO C++ forbids taking address of function %<::main%>");
4203 /* Let &* cancel out to simplify resulting code. */
4204 if (TREE_CODE (arg) == INDIRECT_REF)
4206 /* We don't need to have `current_class_ptr' wrapped in a
4207 NON_LVALUE_EXPR node. */
4208 if (arg == current_class_ref)
4209 return current_class_ptr;
4211 arg = TREE_OPERAND (arg, 0);
4212 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
4214 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
4215 arg = build1 (CONVERT_EXPR, type, arg);
4218 /* Don't let this be an lvalue. */
4223 /* Uninstantiated types are all functions. Taking the
4224 address of a function is a no-op, so just return the
4227 gcc_assert (TREE_CODE (arg) != IDENTIFIER_NODE
4228 || !IDENTIFIER_OPNAME_P (arg));
4230 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
4231 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
4233 /* They're trying to take the address of a unique non-static
4234 member function. This is ill-formed (except in MS-land),
4235 but let's try to DTRT.
4236 Note: We only handle unique functions here because we don't
4237 want to complain if there's a static overload; non-unique
4238 cases will be handled by instantiate_type. But we need to
4239 handle this case here to allow casts on the resulting PMF.
4240 We could defer this in non-MS mode, but it's easier to give
4241 a useful error here. */
4243 /* Inside constant member functions, the `this' pointer
4244 contains an extra const qualifier. TYPE_MAIN_VARIANT
4245 is used here to remove this const from the diagnostics
4246 and the created OFFSET_REF. */
4247 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
4248 tree fn = get_first_fn (TREE_OPERAND (arg, 1));
4251 if (! flag_ms_extensions)
4253 tree name = DECL_NAME (fn);
4254 if (current_class_type
4255 && TREE_OPERAND (arg, 0) == current_class_ref)
4256 /* An expression like &memfn. */
4257 pedwarn ("ISO C++ forbids taking the address of an unqualified"
4258 " or parenthesized non-static member function to form"
4259 " a pointer to member function. Say %<&%T::%D%>",
4262 pedwarn ("ISO C++ forbids taking the address of a bound member"
4263 " function to form a pointer to member function."
4267 arg = build_offset_ref (base, fn, /*address_p=*/true);
4271 if (type_unknown_p (arg))
4272 return build1 (ADDR_EXPR, unknown_type_node, arg);
4274 /* Handle complex lvalues (when permitted)
4275 by reduction to simpler cases. */
4276 val = unary_complex_lvalue (code, arg);
4280 switch (TREE_CODE (arg))
4285 case FIX_TRUNC_EXPR:
4286 case FIX_FLOOR_EXPR:
4287 case FIX_ROUND_EXPR:
4289 if (! lvalue_p (arg) && pedantic)
4290 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4294 arg = OVL_CURRENT (arg);
4298 /* Turn a reference to a non-static data member into a
4299 pointer-to-member. */
4304 if (!PTRMEM_OK_P (arg))
4305 return build_unary_op (code, arg, 0);
4307 t = TREE_OPERAND (arg, 1);
4308 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4310 error ("cannot create pointer to reference member %qD", t);
4311 return error_mark_node;
4314 type = build_ptrmem_type (context_for_name_lookup (t),
4316 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4324 /* Anything not already handled and not a true memory reference
4326 if (TREE_CODE (argtype) != FUNCTION_TYPE
4327 && TREE_CODE (argtype) != METHOD_TYPE
4328 && TREE_CODE (arg) != OFFSET_REF
4329 && !lvalue_or_else (arg, lv_addressof))
4330 return error_mark_node;
4332 if (argtype != error_mark_node)
4333 argtype = build_pointer_type (argtype);
4335 /* In a template, we are processing a non-dependent expression
4336 so we can just form an ADDR_EXPR with the correct type. */
4337 if (processing_template_decl)
4339 val = build_address (arg);
4340 if (TREE_CODE (arg) == OFFSET_REF)
4341 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4345 if (TREE_CODE (arg) != COMPONENT_REF)
4347 val = build_address (arg);
4348 if (TREE_CODE (arg) == OFFSET_REF)
4349 PTRMEM_OK_P (val) = PTRMEM_OK_P (arg);
4351 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4353 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4355 /* We can only get here with a single static member
4357 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
4358 && DECL_STATIC_FUNCTION_P (fn));
4360 val = build_address (fn);
4361 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4362 /* Do not lose object's side effects. */
4363 val = build2 (COMPOUND_EXPR, TREE_TYPE (val),
4364 TREE_OPERAND (arg, 0), val);
4366 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4368 error ("attempt to take address of bit-field structure member %qD",
4369 TREE_OPERAND (arg, 1));
4370 return error_mark_node;
4374 tree object = TREE_OPERAND (arg, 0);
4375 tree field = TREE_OPERAND (arg, 1);
4376 gcc_assert (same_type_ignoring_top_level_qualifiers_p
4377 (TREE_TYPE (object), decl_type_context (field)));
4378 val = build_address (arg);
4381 if (TREE_CODE (argtype) == POINTER_TYPE
4382 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4384 build_ptrmemfunc_type (argtype);
4385 val = build_ptrmemfunc (argtype, val, 0,
4386 /*c_cast_p=*/false);
4398 argtype = TREE_TYPE (arg);
4399 return fold_if_not_in_template (build1 (code, argtype, arg));
4402 error ("%s", errstring);
4403 return error_mark_node;
4406 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4407 for certain kinds of expressions which are not really lvalues
4408 but which we can accept as lvalues.
4410 If ARG is not a kind of expression we can handle, return
4414 unary_complex_lvalue (enum tree_code code, tree arg)
4416 /* Inside a template, making these kinds of adjustments is
4417 pointless; we are only concerned with the type of the
4419 if (processing_template_decl)
4422 /* Handle (a, b) used as an "lvalue". */
4423 if (TREE_CODE (arg) == COMPOUND_EXPR)
4425 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4426 return build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4427 TREE_OPERAND (arg, 0), real_result);
4430 /* Handle (a ? b : c) used as an "lvalue". */
4431 if (TREE_CODE (arg) == COND_EXPR
4432 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4433 return rationalize_conditional_expr (code, arg);
4435 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4436 if (TREE_CODE (arg) == MODIFY_EXPR
4437 || TREE_CODE (arg) == PREINCREMENT_EXPR
4438 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4440 tree lvalue = TREE_OPERAND (arg, 0);
4441 if (TREE_SIDE_EFFECTS (lvalue))
4443 lvalue = stabilize_reference (lvalue);
4444 arg = build2 (TREE_CODE (arg), TREE_TYPE (arg),
4445 lvalue, TREE_OPERAND (arg, 1));
4447 return unary_complex_lvalue
4448 (code, build2 (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4451 if (code != ADDR_EXPR)
4454 /* Handle (a = b) used as an "lvalue" for `&'. */
4455 if (TREE_CODE (arg) == MODIFY_EXPR
4456 || TREE_CODE (arg) == INIT_EXPR)
4458 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4459 arg = build2 (COMPOUND_EXPR, TREE_TYPE (real_result),
4461 TREE_NO_WARNING (arg) = 1;
4465 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4466 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4467 || TREE_CODE (arg) == OFFSET_REF)
4470 /* We permit compiler to make function calls returning
4471 objects of aggregate type look like lvalues. */
4475 if (TREE_CODE (targ) == SAVE_EXPR)
4476 targ = TREE_OPERAND (targ, 0);
4478 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4480 if (TREE_CODE (arg) == SAVE_EXPR)
4483 targ = build_cplus_new (TREE_TYPE (arg), arg);
4484 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4487 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4488 return build3 (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4489 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4492 /* Don't let anything else be handled specially. */
4496 /* Mark EXP saying that we need to be able to take the
4497 address of it; it should not be allocated in a register.
4498 Value is true if successful.
4500 C++: we do not allow `current_class_ptr' to be addressable. */
4503 cxx_mark_addressable (tree exp)
4508 switch (TREE_CODE (x))
4515 x = TREE_OPERAND (x, 0);
4519 if (x == current_class_ptr)
4521 error ("cannot take the address of %<this%>, which is an rvalue expression");
4522 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4528 /* Caller should not be trying to mark initialized
4529 constant fields addressable. */
4530 gcc_assert (DECL_LANG_SPECIFIC (x) == 0
4531 || DECL_IN_AGGR_P (x) == 0
4533 || DECL_EXTERNAL (x));
4538 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4539 && !DECL_ARTIFICIAL (x))
4541 if (TREE_CODE (x) == VAR_DECL && DECL_HARD_REGISTER (x))
4544 ("address of explicit register variable %qD requested", x);
4547 else if (extra_warnings)
4549 (OPT_Wextra, "address requested for %qD, which is declared %<register%>", x);
4551 TREE_ADDRESSABLE (x) = 1;
4555 TREE_ADDRESSABLE (x) = 1;
4559 TREE_ADDRESSABLE (x) = 1;
4563 TREE_ADDRESSABLE (x) = 1;
4564 cxx_mark_addressable (TREE_OPERAND (x, 0));
4572 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4575 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4577 tree orig_ifexp = ifexp;
4578 tree orig_op1 = op1;
4579 tree orig_op2 = op2;
4582 if (processing_template_decl)
4584 /* The standard says that the expression is type-dependent if
4585 IFEXP is type-dependent, even though the eventual type of the
4586 expression doesn't dependent on IFEXP. */
4587 if (type_dependent_expression_p (ifexp)
4588 /* As a GNU extension, the middle operand may be omitted. */
4589 || (op1 && type_dependent_expression_p (op1))
4590 || type_dependent_expression_p (op2))
4591 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4592 ifexp = build_non_dependent_expr (ifexp);
4594 op1 = build_non_dependent_expr (op1);
4595 op2 = build_non_dependent_expr (op2);
4598 expr = build_conditional_expr (ifexp, op1, op2);
4599 if (processing_template_decl && expr != error_mark_node)
4600 return build_min_non_dep (COND_EXPR, expr,
4601 orig_ifexp, orig_op1, orig_op2);
4605 /* Given a list of expressions, return a compound expression
4606 that performs them all and returns the value of the last of them. */
4608 tree build_x_compound_expr_from_list (tree list, const char *msg)
4610 tree expr = TREE_VALUE (list);
4612 if (TREE_CHAIN (list))
4615 pedwarn ("%s expression list treated as compound expression", msg);
4617 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4618 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4624 /* Handle overloading of the ',' operator when needed. */
4627 build_x_compound_expr (tree op1, tree op2)
4630 tree orig_op1 = op1;
4631 tree orig_op2 = op2;
4633 if (processing_template_decl)
4635 if (type_dependent_expression_p (op1)
4636 || type_dependent_expression_p (op2))
4637 return build_min_nt (COMPOUND_EXPR, op1, op2);
4638 op1 = build_non_dependent_expr (op1);
4639 op2 = build_non_dependent_expr (op2);
4642 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4643 /*overloaded_p=*/NULL);
4645 result = build_compound_expr (op1, op2);
4647 if (processing_template_decl && result != error_mark_node)
4648 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4653 /* Build a compound expression. */
4656 build_compound_expr (tree lhs, tree rhs)
4658 lhs = convert_to_void (lhs, "left-hand operand of comma");
4660 if (lhs == error_mark_node || rhs == error_mark_node)
4661 return error_mark_node;
4663 if (TREE_CODE (rhs) == TARGET_EXPR)
4665 /* If the rhs is a TARGET_EXPR, then build the compound
4666 expression inside the target_expr's initializer. This
4667 helps the compiler to eliminate unnecessary temporaries. */
4668 tree init = TREE_OPERAND (rhs, 1);
4670 init = build2 (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4671 TREE_OPERAND (rhs, 1) = init;
4676 return build2 (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4679 /* Issue a diagnostic message if casting from SRC_TYPE to DEST_TYPE
4680 casts away constness. DIAG_FN gives the function to call if we
4681 need to issue a diagnostic; if it is NULL, no diagnostic will be
4682 issued. DESCRIPTION explains what operation is taking place. */
4685 check_for_casting_away_constness (tree src_type, tree dest_type,
4686 void (*diag_fn)(const char *, ...) ATTRIBUTE_GCC_CXXDIAG(1,2),
4687 const char *description)
4689 if (diag_fn && casts_away_constness (src_type, dest_type))
4690 diag_fn ("%s from type %qT to type %qT casts away constness",
4691 description, src_type, dest_type);
4694 /* Convert EXPR (an expression with pointer-to-member type) to TYPE
4695 (another pointer-to-member type in the same hierarchy) and return
4696 the converted expression. If ALLOW_INVERSE_P is permitted, a
4697 pointer-to-derived may be converted to pointer-to-base; otherwise,
4698 only the other direction is permitted. If C_CAST_P is true, this
4699 conversion is taking place as part of a C-style cast. */
4702 convert_ptrmem (tree type, tree expr, bool allow_inverse_p,
4705 if (TYPE_PTRMEM_P (type))
4709 if (TREE_CODE (expr) == PTRMEM_CST)
4710 expr = cplus_expand_constant (expr);
4711 delta = get_delta_difference (TYPE_PTRMEM_CLASS_TYPE (TREE_TYPE (expr)),
4712 TYPE_PTRMEM_CLASS_TYPE (type),
4715 if (!integer_zerop (delta))
4716 expr = cp_build_binary_op (PLUS_EXPR,
4717 build_nop (ptrdiff_type_node, expr),
4719 return build_nop (type, expr);
4722 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4723 allow_inverse_p, c_cast_p);
4726 /* If EXPR is an INTEGER_CST and ORIG is an arithmetic constant, return
4727 a version of EXPR that has TREE_OVERFLOW and/or TREE_CONSTANT_OVERFLOW
4728 set iff they are set in ORIG. Otherwise, return EXPR unchanged. */
4731 ignore_overflows (tree expr, tree orig)
4733 if (TREE_CODE (expr) == INTEGER_CST
4734 && CONSTANT_CLASS_P (orig)
4735 && TREE_CODE (orig) != STRING_CST
4736 && (TREE_OVERFLOW (expr) != TREE_OVERFLOW (orig)
4737 || TREE_CONSTANT_OVERFLOW (expr)
4738 != TREE_CONSTANT_OVERFLOW (orig)))
4740 if (!TREE_OVERFLOW (orig) && !TREE_CONSTANT_OVERFLOW (orig))
4741 /* Ensure constant sharing. */
4742 expr = build_int_cst_wide (TREE_TYPE (expr),
4743 TREE_INT_CST_LOW (expr),
4744 TREE_INT_CST_HIGH (expr));
4747 /* Avoid clobbering a shared constant. */
4748 expr = copy_node (expr);
4749 TREE_OVERFLOW (expr) = TREE_OVERFLOW (orig);
4750 TREE_CONSTANT_OVERFLOW (expr)
4751 = TREE_CONSTANT_OVERFLOW (orig);
4757 /* Perform a static_cast from EXPR to TYPE. When C_CAST_P is true,
4758 this static_cast is being attempted as one of the possible casts
4759 allowed by a C-style cast. (In that case, accessibility of base
4760 classes is not considered, and it is OK to cast away
4761 constness.) Return the result of the cast. *VALID_P is set to
4762 indicate whether or not the cast was valid. */
4765 build_static_cast_1 (tree type, tree expr, bool c_cast_p,
4771 void (*diag_fn)(const char*, ...) ATTRIBUTE_GCC_CXXDIAG(1,2);
4774 /* Assume the cast is valid. */
4777 intype = TREE_TYPE (expr);
4779 /* Save casted types in the function's used types hash table. */
4780 used_types_insert (type);
4782 /* Determine what to do when casting away constness. */
4785 /* C-style casts are allowed to cast away constness. With
4786 WARN_CAST_QUAL, we still want to issue a warning. */
4787 diag_fn = warn_cast_qual ? warning0 : NULL;
4792 /* A static_cast may not cast away constness. */
4794 desc = "static_cast";
4797 /* [expr.static.cast]
4799 An lvalue of type "cv1 B", where B is a class type, can be cast
4800 to type "reference to cv2 D", where D is a class derived (clause
4801 _class.derived_) from B, if a valid standard conversion from
4802 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4803 same cv-qualification as, or greater cv-qualification than, cv1,
4804 and B is not a virtual base class of D. */
4805 /* We check this case before checking the validity of "TYPE t =
4806 EXPR;" below because for this case:
4809 struct D : public B { D(const B&); };
4811 void f() { static_cast<const D&>(b); }
4813 we want to avoid constructing a new D. The standard is not
4814 completely clear about this issue, but our interpretation is
4815 consistent with other compilers. */
4816 if (TREE_CODE (type) == REFERENCE_TYPE
4817 && CLASS_TYPE_P (TREE_TYPE (type))
4818 && CLASS_TYPE_P (intype)
4819 && real_lvalue_p (expr)
4820 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4821 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4822 build_pointer_type (TYPE_MAIN_VARIANT
4823 (TREE_TYPE (type))))
4825 || at_least_as_qualified_p (TREE_TYPE (type), intype)))
4829 /* There is a standard conversion from "D*" to "B*" even if "B"
4830 is ambiguous or inaccessible. If this is really a
4831 static_cast, then we check both for inaccessibility and
4832 ambiguity. However, if this is a static_cast being performed
4833 because the user wrote a C-style cast, then accessibility is
4835 base = lookup_base (TREE_TYPE (type), intype,
4836 c_cast_p ? ba_unique : ba_check,
4839 /* Convert from "B*" to "D*". This function will check that "B"
4840 is not a virtual base of "D". */
4841 expr = build_base_path (MINUS_EXPR, build_address (expr),
4842 base, /*nonnull=*/false);
4843 /* Convert the pointer to a reference -- but then remember that
4844 there are no expressions with reference type in C++. */
4845 return convert_from_reference (build_nop (type, expr));
4850 /* [expr.static.cast]
4852 An expression e can be explicitly converted to a type T using a
4853 static_cast of the form static_cast<T>(e) if the declaration T
4854 t(e);" is well-formed, for some invented temporary variable
4856 result = perform_direct_initialization_if_possible (type, expr,
4860 result = convert_from_reference (result);
4862 /* Ignore any integer overflow caused by the cast. */
4863 result = ignore_overflows (result, orig);
4865 /* [expr.static.cast]
4867 If T is a reference type, the result is an lvalue; otherwise,
4868 the result is an rvalue. */
4869 if (TREE_CODE (type) != REFERENCE_TYPE)
4870 result = rvalue (result);
4874 /* [expr.static.cast]
4876 Any expression can be explicitly converted to type cv void. */
4877 if (TREE_CODE (type) == VOID_TYPE)
4878 return convert_to_void (expr, /*implicit=*/NULL);
4880 /* [expr.static.cast]
4882 The inverse of any standard conversion sequence (clause _conv_),
4883 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4884 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4885 (_conv.bool_) conversions, can be performed explicitly using
4886 static_cast subject to the restriction that the explicit
4887 conversion does not cast away constness (_expr.const.cast_), and
4888 the following additional rules for specific cases: */
4889 /* For reference, the conversions not excluded are: integral
4890 promotions, floating point promotion, integral conversions,
4891 floating point conversions, floating-integral conversions,
4892 pointer conversions, and pointer to member conversions. */
4895 A value of integral _or enumeration_ type can be explicitly
4896 converted to an enumeration type. */
4897 /* The effect of all that is that any conversion between any two
4898 types which are integral, floating, or enumeration types can be
4900 if ((INTEGRAL_TYPE_P (type) || SCALAR_FLOAT_TYPE_P (type))
4901 && (INTEGRAL_TYPE_P (intype) || SCALAR_FLOAT_TYPE_P (intype)))
4903 expr = ocp_convert (type, expr, CONV_C_CAST, LOOKUP_NORMAL);
4905 /* Ignore any integer overflow caused by the cast. */
4906 expr = ignore_overflows (expr, orig);
4910 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4911 && CLASS_TYPE_P (TREE_TYPE (type))
4912 && CLASS_TYPE_P (TREE_TYPE (intype))
4913 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4914 (TREE_TYPE (intype))),
4915 build_pointer_type (TYPE_MAIN_VARIANT
4916 (TREE_TYPE (type)))))
4921 check_for_casting_away_constness (intype, type, diag_fn, desc);
4922 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
4923 c_cast_p ? ba_unique : ba_check,
4925 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4928 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4929 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4936 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4937 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4939 if (TYPE_PTRMEM_P (type))
4941 t1 = (build_ptrmem_type
4943 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4944 t2 = (build_ptrmem_type
4946 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4953 if (can_convert (t1, t2))
4956 check_for_casting_away_constness (intype, type, diag_fn,
4958 return convert_ptrmem (type, expr, /*allow_inverse_p=*/1,
4963 /* [expr.static.cast]
4965 An rvalue of type "pointer to cv void" can be explicitly
4966 converted to a pointer to object type. A value of type pointer
4967 to object converted to "pointer to cv void" and back to the
4968 original pointer type will have its original value. */
4969 if (TREE_CODE (intype) == POINTER_TYPE
4970 && VOID_TYPE_P (TREE_TYPE (intype))
4971 && TYPE_PTROB_P (type))
4974 check_for_casting_away_constness (intype, type, diag_fn, desc);
4975 return build_nop (type, expr);
4979 return error_mark_node;
4982 /* Return an expression representing static_cast<TYPE>(EXPR). */
4985 build_static_cast (tree type, tree expr)
4990 if (type == error_mark_node || expr == error_mark_node)
4991 return error_mark_node;
4993 if (processing_template_decl)
4995 expr = build_min (STATIC_CAST_EXPR, type, expr);
4996 /* We don't know if it will or will not have side effects. */
4997 TREE_SIDE_EFFECTS (expr) = 1;
4998 return convert_from_reference (expr);
5001 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5002 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5003 if (TREE_CODE (type) != REFERENCE_TYPE
5004 && TREE_CODE (expr) == NOP_EXPR
5005 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5006 expr = TREE_OPERAND (expr, 0);
5008 result = build_static_cast_1 (type, expr, /*c_cast_p=*/false, &valid_p);
5012 error ("invalid static_cast from type %qT to type %qT",
5013 TREE_TYPE (expr), type);
5014 return error_mark_node;
5017 /* EXPR is an expression with member function or pointer-to-member
5018 function type. TYPE is a pointer type. Converting EXPR to TYPE is
5019 not permitted by ISO C++, but we accept it in some modes. If we
5020 are not in one of those modes, issue a diagnostic. Return the
5021 converted expression. */
5024 convert_member_func_to_ptr (tree type, tree expr)
5029 intype = TREE_TYPE (expr);
5030 gcc_assert (TYPE_PTRMEMFUNC_P (intype)
5031 || TREE_CODE (intype) == METHOD_TYPE);
5033 if (pedantic || warn_pmf2ptr)
5034 pedwarn ("converting from %qT to %qT", intype, type);
5036 if (TREE_CODE (intype) == METHOD_TYPE)
5037 expr = build_addr_func (expr);
5038 else if (TREE_CODE (expr) == PTRMEM_CST)
5039 expr = build_address (PTRMEM_CST_MEMBER (expr));
5042 decl = maybe_dummy_object (TYPE_PTRMEM_CLASS_TYPE (intype), 0);
5043 decl = build_address (decl);
5044 expr = get_member_function_from_ptrfunc (&decl, expr);
5047 return build_nop (type, expr);
5050 /* Return a representation for a reinterpret_cast from EXPR to TYPE.
5051 If C_CAST_P is true, this reinterpret cast is being done as part of
5052 a C-style cast. If VALID_P is non-NULL, *VALID_P is set to
5053 indicate whether or not reinterpret_cast was valid. */
5056 build_reinterpret_cast_1 (tree type, tree expr, bool c_cast_p,
5061 /* Assume the cast is invalid. */
5065 if (type == error_mark_node || error_operand_p (expr))
5066 return error_mark_node;
5068 intype = TREE_TYPE (expr);
5070 /* Save casted types in the function's used types hash table. */
5071 used_types_insert (type);
5073 /* [expr.reinterpret.cast]
5074 An lvalue expression of type T1 can be cast to the type
5075 "reference to T2" if an expression of type "pointer to T1" can be
5076 explicitly converted to the type "pointer to T2" using a
5077 reinterpret_cast. */
5078 if (TREE_CODE (type) == REFERENCE_TYPE)
5080 if (! real_lvalue_p (expr))
5082 error ("invalid cast of an rvalue expression of type "
5085 return error_mark_node;
5088 /* Warn about a reinterpret_cast from "A*" to "B&" if "A" and
5089 "B" are related class types; the reinterpret_cast does not
5090 adjust the pointer. */
5091 if (TYPE_PTR_P (intype)
5092 && (comptypes (TREE_TYPE (intype), TREE_TYPE (type),
5093 COMPARE_BASE | COMPARE_DERIVED)))
5094 warning (0, "casting %qT to %qT does not dereference pointer",
5097 expr = build_unary_op (ADDR_EXPR, expr, 0);
5098 if (expr != error_mark_node)
5099 expr = build_reinterpret_cast_1
5100 (build_pointer_type (TREE_TYPE (type)), expr, c_cast_p,
5102 if (expr != error_mark_node)
5103 expr = build_indirect_ref (expr, 0);
5107 /* As a G++ extension, we consider conversions from member
5108 functions, and pointers to member functions to
5109 pointer-to-function and pointer-to-void types. If
5110 -Wno-pmf-conversions has not been specified,
5111 convert_member_func_to_ptr will issue an error message. */
5112 if ((TYPE_PTRMEMFUNC_P (intype)
5113 || TREE_CODE (intype) == METHOD_TYPE)
5114 && TYPE_PTR_P (type)
5115 && (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE
5116 || VOID_TYPE_P (TREE_TYPE (type))))
5117 return convert_member_func_to_ptr (type, expr);
5119 /* If the cast is not to a reference type, the lvalue-to-rvalue,
5120 array-to-pointer, and function-to-pointer conversions are
5122 expr = decay_conversion (expr);
5124 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5125 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5126 if (TREE_CODE (expr) == NOP_EXPR
5127 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5128 expr = TREE_OPERAND (expr, 0);
5130 if (error_operand_p (expr))
5131 return error_mark_node;
5133 intype = TREE_TYPE (expr);
5135 /* [expr.reinterpret.cast]
5136 A pointer can be converted to any integral type large enough to
5138 if (CP_INTEGRAL_TYPE_P (type) && TYPE_PTR_P (intype))
5140 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
5141 pedwarn ("cast from %qT to %qT loses precision",
5144 /* [expr.reinterpret.cast]
5145 A value of integral or enumeration type can be explicitly
5146 converted to a pointer. */
5147 else if (TYPE_PTR_P (type) && INTEGRAL_OR_ENUMERATION_TYPE_P (intype))
5150 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
5151 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
5152 return fold_if_not_in_template (build_nop (type, expr));
5153 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
5154 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
5159 check_for_casting_away_constness (intype, type, error,
5160 "reinterpret_cast");
5161 /* Warn about possible alignment problems. */
5162 if (STRICT_ALIGNMENT && warn_cast_align
5163 && !VOID_TYPE_P (type)
5164 && TREE_CODE (TREE_TYPE (intype)) != FUNCTION_TYPE
5165 && COMPLETE_TYPE_P (TREE_TYPE (type))
5166 && COMPLETE_TYPE_P (TREE_TYPE (intype))
5167 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (intype)))
5168 warning (0, "cast from %qT to %qT increases required alignment of "
5172 /* We need to strip nops here, because the frontend likes to
5173 create (int *)&a for array-to-pointer decay, instead of &a[0]. */
5175 strict_aliasing_warning (intype, type, sexpr);
5177 return fold_if_not_in_template (build_nop (type, expr));
5179 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
5180 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
5183 /* Only issue a warning, as we have always supported this
5184 where possible, and it is necessary in some cases. DR 195
5185 addresses this issue, but as of 2004/10/26 is still in
5187 warning (0, "ISO C++ forbids casting between pointer-to-function and pointer-to-object");
5188 return fold_if_not_in_template (build_nop (type, expr));
5190 else if (TREE_CODE (type) == VECTOR_TYPE)
5191 return fold_if_not_in_template (convert_to_vector (type, expr));
5192 else if (TREE_CODE (intype) == VECTOR_TYPE)
5193 return fold_if_not_in_template (convert_to_integer (type, expr));
5198 error ("invalid cast from type %qT to type %qT", intype, type);
5199 return error_mark_node;
5202 return cp_convert (type, expr);
5206 build_reinterpret_cast (tree type, tree expr)
5208 if (type == error_mark_node || expr == error_mark_node)
5209 return error_mark_node;
5211 if (processing_template_decl)
5213 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
5215 if (!TREE_SIDE_EFFECTS (t)
5216 && type_dependent_expression_p (expr))
5217 /* There might turn out to be side effects inside expr. */
5218 TREE_SIDE_EFFECTS (t) = 1;
5219 return convert_from_reference (t);
5222 return build_reinterpret_cast_1 (type, expr, /*c_cast_p=*/false,
5226 /* Perform a const_cast from EXPR to TYPE. If the cast is valid,
5227 return an appropriate expression. Otherwise, return
5228 error_mark_node. If the cast is not valid, and COMPLAIN is true,
5229 then a diagnostic will be issued. If VALID_P is non-NULL, we are
5230 performing a C-style cast, its value upon return will indicate
5231 whether or not the conversion succeeded. */
5234 build_const_cast_1 (tree dst_type, tree expr, bool complain,
5238 tree reference_type;
5240 /* Callers are responsible for handling error_mark_node as a
5241 destination type. */
5242 gcc_assert (dst_type != error_mark_node);
5243 /* In a template, callers should be building syntactic
5244 representations of casts, not using this machinery. */
5245 gcc_assert (!processing_template_decl);
5247 /* Assume the conversion is invalid. */
5251 if (!POINTER_TYPE_P (dst_type) && !TYPE_PTRMEM_P (dst_type))
5254 error ("invalid use of const_cast with type %qT, "
5255 "which is not a pointer, "
5256 "reference, nor a pointer-to-data-member type", dst_type);
5257 return error_mark_node;
5260 if (TREE_CODE (TREE_TYPE (dst_type)) == FUNCTION_TYPE)
5263 error ("invalid use of const_cast with type %qT, which is a pointer "
5264 "or reference to a function type", dst_type);
5265 return error_mark_node;
5268 /* Save casted types in the function's used types hash table. */
5269 used_types_insert (dst_type);
5271 src_type = TREE_TYPE (expr);
5272 /* Expressions do not really have reference types. */
5273 if (TREE_CODE (src_type) == REFERENCE_TYPE)
5274 src_type = TREE_TYPE (src_type);
5276 /* [expr.const.cast]
5278 An lvalue of type T1 can be explicitly converted to an lvalue of
5279 type T2 using the cast const_cast<T2&> (where T1 and T2 are object
5280 types) if a pointer to T1 can be explicitly converted to the type
5281 pointer to T2 using a const_cast. */
5282 if (TREE_CODE (dst_type) == REFERENCE_TYPE)
5284 reference_type = dst_type;
5285 if (! real_lvalue_p (expr))
5288 error ("invalid const_cast of an rvalue of type %qT to type %qT",
5289 src_type, dst_type);
5290 return error_mark_node;
5292 dst_type = build_pointer_type (TREE_TYPE (dst_type));
5293 src_type = build_pointer_type (src_type);
5297 reference_type = NULL_TREE;
5298 /* If the destination type is not a reference type, the
5299 lvalue-to-rvalue, array-to-pointer, and function-to-pointer
5300 conversions are performed. */
5301 src_type = type_decays_to (src_type);
5302 if (src_type == error_mark_node)
5303 return error_mark_node;
5306 if ((TYPE_PTR_P (src_type) || TYPE_PTRMEM_P (src_type))
5307 && comp_ptr_ttypes_const (dst_type, src_type))
5312 /* This cast is actually a C-style cast. Issue a warning if
5313 the user is making a potentially unsafe cast. */
5315 check_for_casting_away_constness (src_type, dst_type,
5321 expr = build_unary_op (ADDR_EXPR, expr, 0);
5322 expr = build_nop (reference_type, expr);
5323 return convert_from_reference (expr);
5327 expr = decay_conversion (expr);
5328 /* build_c_cast puts on a NOP_EXPR to make the result not an
5329 lvalue. Strip such NOP_EXPRs if VALUE is being used in
5330 non-lvalue context. */
5331 if (TREE_CODE (expr) == NOP_EXPR
5332 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
5333 expr = TREE_OPERAND (expr, 0);
5334 return build_nop (dst_type, expr);
5339 error ("invalid const_cast from type %qT to type %qT",
5340 src_type, dst_type);
5341 return error_mark_node;
5345 build_const_cast (tree type, tree expr)
5347 if (type == error_mark_node || error_operand_p (expr))
5348 return error_mark_node;
5350 if (processing_template_decl)
5352 tree t = build_min (CONST_CAST_EXPR, type, expr);
5354 if (!TREE_SIDE_EFFECTS (t)
5355 && type_dependent_expression_p (expr))
5356 /* There might turn out to be side effects inside expr. */
5357 TREE_SIDE_EFFECTS (t) = 1;
5358 return convert_from_reference (t);
5361 return build_const_cast_1 (type, expr, /*complain=*/true,
5365 /* Build an expression representing an explicit C-style cast to type
5366 TYPE of expression EXPR. */
5369 build_c_cast (tree type, tree expr)
5375 if (type == error_mark_node || error_operand_p (expr))
5376 return error_mark_node;
5378 if (processing_template_decl)
5380 tree t = build_min (CAST_EXPR, type,
5381 tree_cons (NULL_TREE, value, NULL_TREE));
5382 /* We don't know if it will or will not have side effects. */
5383 TREE_SIDE_EFFECTS (t) = 1;
5384 return convert_from_reference (t);
5387 /* Casts to a (pointer to a) specific ObjC class (or 'id' or
5388 'Class') should always be retained, because this information aids
5389 in method lookup. */
5390 if (objc_is_object_ptr (type)
5391 && objc_is_object_ptr (TREE_TYPE (expr)))
5392 return build_nop (type, expr);
5394 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5395 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
5396 if (TREE_CODE (type) != REFERENCE_TYPE
5397 && TREE_CODE (value) == NOP_EXPR
5398 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
5399 value = TREE_OPERAND (value, 0);
5401 if (TREE_CODE (type) == ARRAY_TYPE)
5403 /* Allow casting from T1* to T2[] because Cfront allows it.
5404 NIHCL uses it. It is not valid ISO C++ however. */
5405 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
5407 pedwarn ("ISO C++ forbids casting to an array type %qT", type);
5408 type = build_pointer_type (TREE_TYPE (type));
5412 error ("ISO C++ forbids casting to an array type %qT", type);
5413 return error_mark_node;
5417 if (TREE_CODE (type) == FUNCTION_TYPE
5418 || TREE_CODE (type) == METHOD_TYPE)
5420 error ("invalid cast to function type %qT", type);
5421 return error_mark_node;
5424 /* A C-style cast can be a const_cast. */
5425 result = build_const_cast_1 (type, value, /*complain=*/false,
5430 /* Or a static cast. */
5431 result = build_static_cast_1 (type, value, /*c_cast_p=*/true,
5433 /* Or a reinterpret_cast. */
5435 result = build_reinterpret_cast_1 (type, value, /*c_cast_p=*/true,
5437 /* The static_cast or reinterpret_cast may be followed by a
5440 /* A valid cast may result in errors if, for example, a
5441 conversion to am ambiguous base class is required. */
5442 && !error_operand_p (result))
5446 /* Non-class rvalues always have cv-unqualified type. */
5447 if (!CLASS_TYPE_P (type))
5448 type = TYPE_MAIN_VARIANT (type);
5449 result_type = TREE_TYPE (result);
5450 if (!CLASS_TYPE_P (result_type))
5451 result_type = TYPE_MAIN_VARIANT (result_type);
5452 /* If the type of RESULT does not match TYPE, perform a
5453 const_cast to make it match. If the static_cast or
5454 reinterpret_cast succeeded, we will differ by at most
5455 cv-qualification, so the follow-on const_cast is guaranteed
5457 if (!same_type_p (non_reference (type), non_reference (result_type)))
5459 result = build_const_cast_1 (type, result, false, &valid_p);
5460 gcc_assert (valid_p);
5465 return error_mark_node;
5468 /* Build an assignment expression of lvalue LHS from value RHS.
5469 MODIFYCODE is the code for a binary operator that we use
5470 to combine the old value of LHS with RHS to get the new value.
5471 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
5473 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
5476 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5480 tree lhstype = TREE_TYPE (lhs);
5481 tree olhstype = lhstype;
5482 tree olhs = NULL_TREE;
5483 bool plain_assign = (modifycode == NOP_EXPR);
5485 /* Avoid duplicate error messages from operands that had errors. */
5486 if (error_operand_p (lhs) || error_operand_p (rhs))
5487 return error_mark_node;
5489 /* Handle control structure constructs used as "lvalues". */
5490 switch (TREE_CODE (lhs))
5492 /* Handle --foo = 5; as these are valid constructs in C++. */
5493 case PREDECREMENT_EXPR:
5494 case PREINCREMENT_EXPR:
5495 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5496 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5497 stabilize_reference (TREE_OPERAND (lhs, 0)),
5498 TREE_OPERAND (lhs, 1));
5499 return build2 (COMPOUND_EXPR, lhstype,
5501 build_modify_expr (TREE_OPERAND (lhs, 0),
5504 /* Handle (a, b) used as an "lvalue". */
5506 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
5508 if (newrhs == error_mark_node)
5509 return error_mark_node;
5510 return build2 (COMPOUND_EXPR, lhstype,
5511 TREE_OPERAND (lhs, 0), newrhs);
5514 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
5515 lhs = build2 (TREE_CODE (lhs), TREE_TYPE (lhs),
5516 stabilize_reference (TREE_OPERAND (lhs, 0)),
5517 TREE_OPERAND (lhs, 1));
5518 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
5519 if (newrhs == error_mark_node)
5520 return error_mark_node;
5521 return build2 (COMPOUND_EXPR, lhstype, lhs, newrhs);
5525 /* MIN_EXPR and MAX_EXPR are currently only permitted as lvalues,
5526 when neither operand has side-effects. */
5527 if (!lvalue_or_else (lhs, lv_assign))
5528 return error_mark_node;
5530 gcc_assert (!TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0))
5531 && !TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 1)));
5533 lhs = build3 (COND_EXPR, TREE_TYPE (lhs),
5534 build2 (TREE_CODE (lhs) == MIN_EXPR ? LE_EXPR : GE_EXPR,
5536 TREE_OPERAND (lhs, 0),
5537 TREE_OPERAND (lhs, 1)),
5538 TREE_OPERAND (lhs, 0),
5539 TREE_OPERAND (lhs, 1));
5542 /* Handle (a ? b : c) used as an "lvalue". */
5545 /* Produce (a ? (b = rhs) : (c = rhs))
5546 except that the RHS goes through a save-expr
5547 so the code to compute it is only emitted once. */
5549 tree preeval = NULL_TREE;
5551 rhs = stabilize_expr (rhs, &preeval);
5553 /* Check this here to avoid odd errors when trying to convert
5554 a throw to the type of the COND_EXPR. */
5555 if (!lvalue_or_else (lhs, lv_assign))
5556 return error_mark_node;
5558 cond = build_conditional_expr
5559 (TREE_OPERAND (lhs, 0),
5560 build_modify_expr (TREE_OPERAND (lhs, 1),
5562 build_modify_expr (TREE_OPERAND (lhs, 2),
5565 if (cond == error_mark_node)
5567 /* Make sure the code to compute the rhs comes out
5568 before the split. */
5570 cond = build2 (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5578 if (modifycode == INIT_EXPR)
5580 if (TREE_CODE (rhs) == CONSTRUCTOR)
5582 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5583 /* Call convert to generate an error; see PR 11063. */
5584 rhs = convert (lhstype, rhs);
5585 result = build2 (INIT_EXPR, lhstype, lhs, rhs);
5586 TREE_SIDE_EFFECTS (result) = 1;
5589 else if (! IS_AGGR_TYPE (lhstype))
5590 /* Do the default thing. */;
5593 result = build_special_member_call (lhs, complete_ctor_identifier,
5594 build_tree_list (NULL_TREE, rhs),
5595 lhstype, LOOKUP_NORMAL);
5596 if (result == NULL_TREE)
5597 return error_mark_node;
5603 lhs = require_complete_type (lhs);
5604 if (lhs == error_mark_node)
5605 return error_mark_node;
5607 if (modifycode == NOP_EXPR)
5609 /* `operator=' is not an inheritable operator. */
5610 if (! IS_AGGR_TYPE (lhstype))
5611 /* Do the default thing. */;
5614 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5615 lhs, rhs, make_node (NOP_EXPR),
5616 /*overloaded_p=*/NULL);
5617 if (result == NULL_TREE)
5618 return error_mark_node;
5625 /* A binary op has been requested. Combine the old LHS
5626 value with the RHS producing the value we should actually
5627 store into the LHS. */
5629 gcc_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE));
5630 lhs = stabilize_reference (lhs);
5631 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
5632 if (newrhs == error_mark_node)
5634 error (" in evaluation of %<%Q(%#T, %#T)%>", modifycode,
5635 TREE_TYPE (lhs), TREE_TYPE (rhs));
5636 return error_mark_node;
5639 /* Now it looks like a plain assignment. */
5640 modifycode = NOP_EXPR;
5642 gcc_assert (TREE_CODE (lhstype) != REFERENCE_TYPE);
5643 gcc_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE);
5646 /* The left-hand side must be an lvalue. */
5647 if (!lvalue_or_else (lhs, lv_assign))
5648 return error_mark_node;
5650 /* Warn about modifying something that is `const'. Don't warn if
5651 this is initialization. */
5652 if (modifycode != INIT_EXPR
5653 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5654 /* Functions are not modifiable, even though they are
5656 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5657 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5658 /* If it's an aggregate and any field is const, then it is
5659 effectively const. */
5660 || (CLASS_TYPE_P (lhstype)
5661 && C_TYPE_FIELDS_READONLY (lhstype))))
5662 readonly_error (lhs, "assignment", 0);
5664 /* If storing into a structure or union member, it has probably been
5665 given type `int'. Compute the type that would go with the actual
5666 amount of storage the member occupies. */
5668 if (TREE_CODE (lhs) == COMPONENT_REF
5669 && (TREE_CODE (lhstype) == INTEGER_TYPE
5670 || TREE_CODE (lhstype) == REAL_TYPE
5671 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5673 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5675 /* If storing in a field that is in actuality a short or narrower
5676 than one, we must store in the field in its actual type. */
5678 if (lhstype != TREE_TYPE (lhs))
5680 /* Avoid warnings converting integral types back into enums for
5682 if (TREE_CODE (lhstype) == INTEGER_TYPE
5683 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5685 if (TREE_SIDE_EFFECTS (lhs))
5686 lhs = stabilize_reference (lhs);
5689 lhs = copy_node (lhs);
5690 TREE_TYPE (lhs) = lhstype;
5694 /* Convert new value to destination type. */
5696 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5700 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5701 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5703 error ("incompatible types in assignment of %qT to %qT",
5704 TREE_TYPE (rhs), lhstype);
5705 return error_mark_node;
5708 /* Allow array assignment in compiler-generated code. */
5709 if (! DECL_ARTIFICIAL (current_function_decl))
5710 pedwarn ("ISO C++ forbids assignment of arrays");
5712 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5713 ? 1 + (modifycode != INIT_EXPR): 0;
5714 return build_vec_init (lhs, NULL_TREE, newrhs,
5715 /*explicit_default_init_p=*/false,
5719 if (modifycode == INIT_EXPR)
5720 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5721 "initialization", NULL_TREE, 0);
5724 /* Avoid warnings on enum bit fields. */
5725 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5726 && TREE_CODE (lhstype) == INTEGER_TYPE)
5728 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5730 newrhs = convert_force (lhstype, newrhs, 0);
5733 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5735 if (TREE_CODE (newrhs) == CALL_EXPR
5736 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5737 newrhs = build_cplus_new (lhstype, newrhs);
5739 /* Can't initialize directly from a TARGET_EXPR, since that would
5740 cause the lhs to be constructed twice, and possibly result in
5741 accidental self-initialization. So we force the TARGET_EXPR to be
5742 expanded without a target. */
5743 if (TREE_CODE (newrhs) == TARGET_EXPR)
5744 newrhs = build2 (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5745 TREE_OPERAND (newrhs, 0));
5748 if (newrhs == error_mark_node)
5749 return error_mark_node;
5751 if (c_dialect_objc () && flag_objc_gc)
5753 result = objc_generate_write_barrier (lhs, modifycode, newrhs);
5759 result = build2 (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5760 lhstype, lhs, newrhs);
5762 TREE_SIDE_EFFECTS (result) = 1;
5764 TREE_NO_WARNING (result) = 1;
5766 /* If we got the LHS in a different type for storing in,
5767 convert the result back to the nominal type of LHS
5768 so that the value we return always has the same type
5769 as the LHS argument. */
5771 if (olhstype == TREE_TYPE (result))
5775 result = build2 (COMPOUND_EXPR, olhstype, result, olhs);
5776 TREE_NO_WARNING (result) = 1;
5779 return convert_for_assignment (olhstype, result, "assignment",
5784 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5786 if (processing_template_decl)
5787 return build_min_nt (MODOP_EXPR, lhs,
5788 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5790 if (modifycode != NOP_EXPR)
5792 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5793 make_node (modifycode),
5794 /*overloaded_p=*/NULL);
5797 TREE_NO_WARNING (rval) = 1;
5801 return build_modify_expr (lhs, modifycode, rhs);
5805 /* Get difference in deltas for different pointer to member function
5806 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5807 the conversion is invalid, the constant is zero. If
5808 ALLOW_INVERSE_P is true, then allow reverse conversions as well.
5809 If C_CAST_P is true this conversion is taking place as part of a
5812 Note that the naming of FROM and TO is kind of backwards; the return
5813 value is what we add to a TO in order to get a FROM. They are named
5814 this way because we call this function to find out how to convert from
5815 a pointer to member of FROM to a pointer to member of TO. */
5818 get_delta_difference (tree from, tree to,
5819 bool allow_inverse_p,
5826 /* Assume no conversion is required. */
5827 result = integer_zero_node;
5828 binfo = lookup_base (to, from, c_cast_p ? ba_unique : ba_check, &kind);
5829 if (kind == bk_inaccessible || kind == bk_ambig)
5830 error (" in pointer to member function conversion");
5833 if (kind != bk_via_virtual)
5834 result = BINFO_OFFSET (binfo);
5837 tree virt_binfo = binfo_from_vbase (binfo);
5839 /* This is a reinterpret cast, we choose to do nothing. */
5840 if (allow_inverse_p)
5841 warning (0, "pointer to member cast via virtual base %qT",
5842 BINFO_TYPE (virt_binfo));
5844 error ("pointer to member conversion via virtual base %qT",
5845 BINFO_TYPE (virt_binfo));
5848 else if (same_type_ignoring_top_level_qualifiers_p (from, to))
5849 /* Pointer to member of incomplete class is permitted*/;
5850 else if (!allow_inverse_p)
5852 error_not_base_type (from, to);
5853 error (" in pointer to member conversion");
5857 binfo = lookup_base (from, to, c_cast_p ? ba_unique : ba_check, &kind);
5860 if (kind != bk_via_virtual)
5861 result = size_diffop (size_zero_node, BINFO_OFFSET (binfo));
5864 /* This is a reinterpret cast, we choose to do nothing. */
5865 tree virt_binfo = binfo_from_vbase (binfo);
5867 warning (0, "pointer to member cast via virtual base %qT",
5868 BINFO_TYPE (virt_binfo));
5873 return fold_if_not_in_template (convert_to_integer (ptrdiff_type_node,
5877 /* Return a constructor for the pointer-to-member-function TYPE using
5878 the other components as specified. */
5881 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5886 VEC(constructor_elt, gc) *v;
5888 /* Pull the FIELD_DECLs out of the type. */
5889 pfn_field = TYPE_FIELDS (type);
5890 delta_field = TREE_CHAIN (pfn_field);
5892 /* Make sure DELTA has the type we want. */
5893 delta = convert_and_check (delta_type_node, delta);
5895 /* Finish creating the initializer. */
5896 v = VEC_alloc(constructor_elt, gc, 2);
5897 CONSTRUCTOR_APPEND_ELT(v, pfn_field, pfn);
5898 CONSTRUCTOR_APPEND_ELT(v, delta_field, delta);
5899 u = build_constructor (type, v);
5900 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
5901 TREE_INVARIANT (u) = TREE_INVARIANT (pfn) & TREE_INVARIANT (delta);
5902 TREE_STATIC (u) = (TREE_CONSTANT (u)
5903 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5905 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5910 /* Build a constructor for a pointer to member function. It can be
5911 used to initialize global variables, local variable, or used
5912 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5915 If FORCE is nonzero, then force this conversion, even if
5916 we would rather not do it. Usually set when using an explicit
5917 cast. A C-style cast is being processed iff C_CAST_P is true.
5919 Return error_mark_node, if something goes wrong. */
5922 build_ptrmemfunc (tree type, tree pfn, int force, bool c_cast_p)
5928 if (error_operand_p (pfn))
5929 return error_mark_node;
5931 pfn_type = TREE_TYPE (pfn);
5932 to_type = build_ptrmemfunc_type (type);
5934 /* Handle multiple conversions of pointer to member functions. */
5935 if (TYPE_PTRMEMFUNC_P (pfn_type))
5937 tree delta = NULL_TREE;
5938 tree npfn = NULL_TREE;
5942 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn, LOOKUP_NORMAL))
5943 error ("invalid conversion to type %qT from type %qT",
5946 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5947 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5951 /* We don't have to do any conversion to convert a
5952 pointer-to-member to its own type. But, we don't want to
5953 just return a PTRMEM_CST if there's an explicit cast; that
5954 cast should make the expression an invalid template argument. */
5955 if (TREE_CODE (pfn) != PTRMEM_CST)
5957 if (same_type_p (to_type, pfn_type))
5959 else if (integer_zerop (n))
5960 return build_reinterpret_cast (to_type, pfn);
5963 if (TREE_SIDE_EFFECTS (pfn))
5964 pfn = save_expr (pfn);
5966 /* Obtain the function pointer and the current DELTA. */
5967 if (TREE_CODE (pfn) == PTRMEM_CST)
5968 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
5971 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
5972 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
5975 /* Just adjust the DELTA field. */
5976 gcc_assert (same_type_ignoring_top_level_qualifiers_p
5977 (TREE_TYPE (delta), ptrdiff_type_node));
5978 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
5979 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
5980 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
5981 return build_ptrmemfunc1 (to_type, delta, npfn);
5984 /* Handle null pointer to member function conversions. */
5985 if (integer_zerop (pfn))
5987 pfn = build_c_cast (type, integer_zero_node);
5988 return build_ptrmemfunc1 (to_type,
5993 if (type_unknown_p (pfn))
5994 return instantiate_type (type, pfn, tf_warning_or_error);
5996 fn = TREE_OPERAND (pfn, 0);
5997 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL
5998 /* In a template, we will have preserved the
6000 || (processing_template_decl && TREE_CODE (fn) == OFFSET_REF));
6001 return make_ptrmem_cst (to_type, fn);
6004 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
6007 ??? There is no consistency as to the types returned for the above
6008 values. Some code acts as if it were a sizetype and some as if it were
6009 integer_type_node. */
6012 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
6014 tree type = TREE_TYPE (cst);
6015 tree fn = PTRMEM_CST_MEMBER (cst);
6016 tree ptr_class, fn_class;
6018 gcc_assert (TREE_CODE (fn) == FUNCTION_DECL);
6020 /* The class that the function belongs to. */
6021 fn_class = DECL_CONTEXT (fn);
6023 /* The class that we're creating a pointer to member of. */
6024 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
6026 /* First, calculate the adjustment to the function's class. */
6027 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0,
6030 if (!DECL_VIRTUAL_P (fn))
6031 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
6034 /* If we're dealing with a virtual function, we have to adjust 'this'
6035 again, to point to the base which provides the vtable entry for
6036 fn; the call will do the opposite adjustment. */
6037 tree orig_class = DECL_CONTEXT (fn);
6038 tree binfo = binfo_or_else (orig_class, fn_class);
6039 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6040 *delta, BINFO_OFFSET (binfo));
6041 *delta = fold_if_not_in_template (*delta);
6043 /* We set PFN to the vtable offset at which the function can be
6044 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
6045 case delta is shifted left, and then incremented). */
6046 *pfn = DECL_VINDEX (fn);
6047 *pfn = build2 (MULT_EXPR, integer_type_node, *pfn,
6048 TYPE_SIZE_UNIT (vtable_entry_type));
6049 *pfn = fold_if_not_in_template (*pfn);
6051 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
6053 case ptrmemfunc_vbit_in_pfn:
6054 *pfn = build2 (PLUS_EXPR, integer_type_node, *pfn,
6056 *pfn = fold_if_not_in_template (*pfn);
6059 case ptrmemfunc_vbit_in_delta:
6060 *delta = build2 (LSHIFT_EXPR, TREE_TYPE (*delta),
6061 *delta, integer_one_node);
6062 *delta = fold_if_not_in_template (*delta);
6063 *delta = build2 (PLUS_EXPR, TREE_TYPE (*delta),
6064 *delta, integer_one_node);
6065 *delta = fold_if_not_in_template (*delta);
6072 *pfn = build_nop (TYPE_PTRMEMFUNC_FN_TYPE (type), *pfn);
6073 *pfn = fold_if_not_in_template (*pfn);
6077 /* Return an expression for PFN from the pointer-to-member function
6081 pfn_from_ptrmemfunc (tree t)
6083 if (TREE_CODE (t) == PTRMEM_CST)
6088 expand_ptrmemfunc_cst (t, &delta, &pfn);
6093 return build_ptrmemfunc_access_expr (t, pfn_identifier);
6096 /* Convert value RHS to type TYPE as preparation for an assignment to
6097 an lvalue of type TYPE. ERRTYPE is a string to use in error
6098 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
6099 are doing the conversion in order to pass the PARMNUMth argument of
6103 convert_for_assignment (tree type, tree rhs,
6104 const char *errtype, tree fndecl, int parmnum)
6107 enum tree_code coder;
6109 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
6110 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
6111 rhs = TREE_OPERAND (rhs, 0);
6113 rhstype = TREE_TYPE (rhs);
6114 coder = TREE_CODE (rhstype);
6116 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
6117 && vector_types_convertible_p (type, rhstype))
6118 return convert (type, rhs);
6120 if (rhs == error_mark_node || rhstype == error_mark_node)
6121 return error_mark_node;
6122 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
6123 return error_mark_node;
6125 /* The RHS of an assignment cannot have void type. */
6126 if (coder == VOID_TYPE)
6128 error ("void value not ignored as it ought to be");
6129 return error_mark_node;
6132 /* Simplify the RHS if possible. */
6133 if (TREE_CODE (rhs) == CONST_DECL)
6134 rhs = DECL_INITIAL (rhs);
6136 if (c_dialect_objc ())
6139 tree rname = fndecl;
6141 if (!strcmp (errtype, "assignment"))
6143 else if (!strcmp (errtype, "initialization"))
6147 tree selector = objc_message_selector ();
6151 if (selector && parmno > 1)
6158 if (objc_compare_types (type, rhstype, parmno, rname))
6159 return convert (type, rhs);
6164 The expression is implicitly converted (clause _conv_) to the
6165 cv-unqualified type of the left operand.
6167 We allow bad conversions here because by the time we get to this point
6168 we are committed to doing the conversion. If we end up doing a bad
6169 conversion, convert_like will complain. */
6170 if (!can_convert_arg_bad (type, rhstype, rhs))
6172 /* When -Wno-pmf-conversions is use, we just silently allow
6173 conversions from pointers-to-members to plain pointers. If
6174 the conversion doesn't work, cp_convert will complain. */
6176 && TYPE_PTR_P (type)
6177 && TYPE_PTRMEMFUNC_P (rhstype))
6178 rhs = cp_convert (strip_top_quals (type), rhs);
6181 /* If the right-hand side has unknown type, then it is an
6182 overloaded function. Call instantiate_type to get error
6184 if (rhstype == unknown_type_node)
6185 instantiate_type (type, rhs, tf_warning_or_error);
6187 error ("cannot convert %qT to %qT for argument %qP to %qD",
6188 rhstype, type, parmnum, fndecl);
6190 error ("cannot convert %qT to %qT in %s", rhstype, type, errtype);
6191 return error_mark_node;
6194 if (warn_missing_format_attribute)
6196 const enum tree_code codel = TREE_CODE (type);
6197 if ((codel == POINTER_TYPE || codel == REFERENCE_TYPE)
6199 && check_missing_format_attribute (type, rhstype))
6200 warning (OPT_Wmissing_format_attribute,
6201 "%s might be a candidate for a format attribute",
6205 return perform_implicit_conversion (strip_top_quals (type), rhs);
6208 /* Convert RHS to be of type TYPE.
6209 If EXP is nonzero, it is the target of the initialization.
6210 ERRTYPE is a string to use in error messages.
6212 Two major differences between the behavior of
6213 `convert_for_assignment' and `convert_for_initialization'
6214 are that references are bashed in the former, while
6215 copied in the latter, and aggregates are assigned in
6216 the former (operator=) while initialized in the
6219 If using constructor make sure no conversion operator exists, if one does
6220 exist, an ambiguity exists.
6222 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
6225 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
6226 const char *errtype, tree fndecl, int parmnum)
6228 enum tree_code codel = TREE_CODE (type);
6230 enum tree_code coder;
6232 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
6233 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
6234 if (TREE_CODE (rhs) == NOP_EXPR
6235 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
6236 && codel != REFERENCE_TYPE)
6237 rhs = TREE_OPERAND (rhs, 0);
6239 if (type == error_mark_node
6240 || rhs == error_mark_node
6241 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
6242 return error_mark_node;
6244 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
6245 && TREE_CODE (type) != ARRAY_TYPE
6246 && (TREE_CODE (type) != REFERENCE_TYPE
6247 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
6248 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
6249 && (TREE_CODE (type) != REFERENCE_TYPE
6250 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
6251 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
6252 rhs = decay_conversion (rhs);
6254 rhstype = TREE_TYPE (rhs);
6255 coder = TREE_CODE (rhstype);
6257 if (coder == ERROR_MARK)
6258 return error_mark_node;
6260 /* We accept references to incomplete types, so we can
6261 return here before checking if RHS is of complete type. */
6263 if (codel == REFERENCE_TYPE)
6265 /* This should eventually happen in convert_arguments. */
6266 int savew = 0, savee = 0;
6269 savew = warningcount, savee = errorcount;
6270 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
6274 if (warningcount > savew)
6275 warning (0, "in passing argument %P of %q+D", parmnum, fndecl);
6276 else if (errorcount > savee)
6277 error ("in passing argument %P of %q+D", parmnum, fndecl);
6283 exp = require_complete_type (exp);
6284 if (exp == error_mark_node)
6285 return error_mark_node;
6287 rhstype = non_reference (rhstype);
6289 type = complete_type (type);
6291 if (IS_AGGR_TYPE (type))
6292 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
6294 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
6297 /* If RETVAL is the address of, or a reference to, a local variable or
6298 temporary give an appropriate warning. */
6301 maybe_warn_about_returning_address_of_local (tree retval)
6303 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
6304 tree whats_returned = retval;
6308 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
6309 whats_returned = TREE_OPERAND (whats_returned, 1);
6310 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
6311 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
6312 || TREE_CODE (whats_returned) == NOP_EXPR)
6313 whats_returned = TREE_OPERAND (whats_returned, 0);
6318 if (TREE_CODE (whats_returned) != ADDR_EXPR)
6320 whats_returned = TREE_OPERAND (whats_returned, 0);
6322 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6324 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
6325 || TREE_CODE (whats_returned) == TARGET_EXPR)
6327 warning (0, "returning reference to temporary");
6330 if (TREE_CODE (whats_returned) == VAR_DECL
6331 && DECL_NAME (whats_returned)
6332 && TEMP_NAME_P (DECL_NAME (whats_returned)))
6334 warning (0, "reference to non-lvalue returned");
6339 if (DECL_P (whats_returned)
6340 && DECL_NAME (whats_returned)
6341 && DECL_FUNCTION_SCOPE_P (whats_returned)
6342 && !(TREE_STATIC (whats_returned)
6343 || TREE_PUBLIC (whats_returned)))
6345 if (TREE_CODE (valtype) == REFERENCE_TYPE)
6346 warning (0, "reference to local variable %q+D returned",
6349 warning (0, "address of local variable %q+D returned",
6355 /* Check that returning RETVAL from the current function is valid.
6356 Return an expression explicitly showing all conversions required to
6357 change RETVAL into the function return type, and to assign it to
6358 the DECL_RESULT for the function. Set *NO_WARNING to true if
6359 code reaches end of non-void function warning shouldn't be issued
6360 on this RETURN_EXPR. */
6363 check_return_expr (tree retval, bool *no_warning)
6366 /* The type actually returned by the function, after any
6369 int fn_returns_value_p;
6371 *no_warning = false;
6373 /* A `volatile' function is one that isn't supposed to return, ever.
6374 (This is a G++ extension, used to get better code for functions
6375 that call the `volatile' function.) */
6376 if (TREE_THIS_VOLATILE (current_function_decl))
6377 warning (0, "function declared %<noreturn%> has a %<return%> statement");
6379 /* Check for various simple errors. */
6380 if (DECL_DESTRUCTOR_P (current_function_decl))
6383 error ("returning a value from a destructor");
6386 else if (DECL_CONSTRUCTOR_P (current_function_decl))
6388 if (in_function_try_handler)
6389 /* If a return statement appears in a handler of the
6390 function-try-block of a constructor, the program is ill-formed. */
6391 error ("cannot return from a handler of a function-try-block of a constructor");
6393 /* You can't return a value from a constructor. */
6394 error ("returning a value from a constructor");
6398 if (processing_template_decl)
6400 current_function_returns_value = 1;
6404 /* When no explicit return-value is given in a function with a named
6405 return value, the named return value is used. */
6406 result = DECL_RESULT (current_function_decl);
6407 valtype = TREE_TYPE (result);
6408 gcc_assert (valtype != NULL_TREE);
6409 fn_returns_value_p = !VOID_TYPE_P (valtype);
6410 if (!retval && DECL_NAME (result) && fn_returns_value_p)
6413 /* Check for a return statement with no return value in a function
6414 that's supposed to return a value. */
6415 if (!retval && fn_returns_value_p)
6417 pedwarn ("return-statement with no value, in function returning %qT",
6419 /* Clear this, so finish_function won't say that we reach the
6420 end of a non-void function (which we don't, we gave a
6422 current_function_returns_null = 0;
6423 /* And signal caller that TREE_NO_WARNING should be set on the
6424 RETURN_EXPR to avoid control reaches end of non-void function
6425 warnings in tree-cfg.c. */
6428 /* Check for a return statement with a value in a function that
6429 isn't supposed to return a value. */
6430 else if (retval && !fn_returns_value_p)
6432 if (VOID_TYPE_P (TREE_TYPE (retval)))
6433 /* You can return a `void' value from a function of `void'
6434 type. In that case, we have to evaluate the expression for
6435 its side-effects. */
6436 finish_expr_stmt (retval);
6438 pedwarn ("return-statement with a value, in function "
6439 "returning 'void'");
6441 current_function_returns_null = 1;
6443 /* There's really no value to return, after all. */
6447 /* Remember that this function can sometimes return without a
6449 current_function_returns_null = 1;
6451 /* Remember that this function did return a value. */
6452 current_function_returns_value = 1;
6454 /* Check for erroneous operands -- but after giving ourselves a
6455 chance to provide an error about returning a value from a void
6457 if (error_operand_p (retval))
6459 current_function_return_value = error_mark_node;
6460 return error_mark_node;
6463 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
6464 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
6465 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
6466 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
6468 && null_ptr_cst_p (retval))
6469 warning (0, "%<operator new%> must not return NULL unless it is "
6470 "declared %<throw()%> (or -fcheck-new is in effect)");
6472 /* Effective C++ rule 15. See also start_function. */
6474 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR))
6478 /* The function return type must be a reference to the current
6480 if (TREE_CODE (valtype) == REFERENCE_TYPE
6481 && same_type_ignoring_top_level_qualifiers_p
6482 (TREE_TYPE (valtype), TREE_TYPE (current_class_ref)))
6484 /* Returning '*this' is obviously OK. */
6485 if (retval == current_class_ref)
6487 /* If we are calling a function whose return type is the same of
6488 the current class reference, it is ok. */
6489 else if (TREE_CODE (retval) == INDIRECT_REF
6490 && TREE_CODE (TREE_OPERAND (retval, 0)) == CALL_EXPR)
6495 warning (OPT_Weffc__, "%<operator=%> should return a reference to %<*this%>");
6498 /* The fabled Named Return Value optimization, as per [class.copy]/15:
6500 [...] For a function with a class return type, if the expression
6501 in the return statement is the name of a local object, and the cv-
6502 unqualified type of the local object is the same as the function
6503 return type, an implementation is permitted to omit creating the tem-
6504 porary object to hold the function return value [...]
6506 So, if this is a value-returning function that always returns the same
6507 local variable, remember it.
6509 It might be nice to be more flexible, and choose the first suitable
6510 variable even if the function sometimes returns something else, but
6511 then we run the risk of clobbering the variable we chose if the other
6512 returned expression uses the chosen variable somehow. And people expect
6513 this restriction, anyway. (jason 2000-11-19)
6515 See finish_function and finalize_nrv for the rest of this optimization. */
6517 if (fn_returns_value_p && flag_elide_constructors)
6519 if (retval != NULL_TREE
6520 && (current_function_return_value == NULL_TREE
6521 || current_function_return_value == retval)
6522 && TREE_CODE (retval) == VAR_DECL
6523 && DECL_CONTEXT (retval) == current_function_decl
6524 && ! TREE_STATIC (retval)
6525 && (DECL_ALIGN (retval)
6526 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
6527 && same_type_p ((TYPE_MAIN_VARIANT
6528 (TREE_TYPE (retval))),
6530 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
6531 current_function_return_value = retval;
6533 current_function_return_value = error_mark_node;
6536 /* We don't need to do any conversions when there's nothing being
6541 /* Do any required conversions. */
6542 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6543 /* No conversions are required. */
6547 /* The type the function is declared to return. */
6548 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6550 /* The functype's return type will have been set to void, if it
6551 was an incomplete type. Just treat this as 'return;' */
6552 if (VOID_TYPE_P (functype))
6553 return error_mark_node;
6555 /* First convert the value to the function's return type, then
6556 to the type of return value's location to handle the
6557 case that functype is smaller than the valtype. */
6558 retval = convert_for_initialization
6559 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
6560 "return", NULL_TREE, 0);
6561 retval = convert (valtype, retval);
6563 /* If the conversion failed, treat this just like `return;'. */
6564 if (retval == error_mark_node)
6566 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6567 else if (! current_function_returns_struct
6568 && TREE_CODE (retval) == TARGET_EXPR
6569 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6570 retval = build2 (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6571 TREE_OPERAND (retval, 0));
6573 maybe_warn_about_returning_address_of_local (retval);
6576 /* Actually copy the value returned into the appropriate location. */
6577 if (retval && retval != result)
6578 retval = build2 (INIT_EXPR, TREE_TYPE (result), result, retval);
6584 /* Returns nonzero if the pointer-type FROM can be converted to the
6585 pointer-type TO via a qualification conversion. If CONSTP is -1,
6586 then we return nonzero if the pointers are similar, and the
6587 cv-qualification signature of FROM is a proper subset of that of TO.
6589 If CONSTP is positive, then all outer pointers have been
6593 comp_ptr_ttypes_real (tree to, tree from, int constp)
6595 bool to_more_cv_qualified = false;
6597 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6599 if (TREE_CODE (to) != TREE_CODE (from))
6602 if (TREE_CODE (from) == OFFSET_TYPE
6603 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
6604 TYPE_OFFSET_BASETYPE (to)))
6607 /* Const and volatile mean something different for function types,
6608 so the usual checks are not appropriate. */
6609 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6611 /* In Objective-C++, some types may have been 'volatilized' by
6612 the compiler for EH; when comparing them here, the volatile
6613 qualification must be ignored. */
6614 bool objc_quals_match = objc_type_quals_match (to, from);
6616 if (!at_least_as_qualified_p (to, from) && !objc_quals_match)
6619 if (!at_least_as_qualified_p (from, to) && !objc_quals_match)
6623 to_more_cv_qualified = true;
6627 constp &= TYPE_READONLY (to);
6630 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
6631 return ((constp >= 0 || to_more_cv_qualified)
6632 && same_type_ignoring_top_level_qualifiers_p (to, from));
6636 /* When comparing, say, char ** to char const **, this function takes
6637 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6638 types to this function. */
6641 comp_ptr_ttypes (tree to, tree from)
6643 return comp_ptr_ttypes_real (to, from, 1);
6646 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6647 type or inheritance-related types, regardless of cv-quals. */
6650 ptr_reasonably_similar (tree to, tree from)
6652 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6654 /* Any target type is similar enough to void. */
6655 if (TREE_CODE (to) == VOID_TYPE
6656 || TREE_CODE (from) == VOID_TYPE)
6659 if (TREE_CODE (to) != TREE_CODE (from))
6662 if (TREE_CODE (from) == OFFSET_TYPE
6663 && comptypes (TYPE_OFFSET_BASETYPE (to),
6664 TYPE_OFFSET_BASETYPE (from),
6665 COMPARE_BASE | COMPARE_DERIVED))
6668 if (TREE_CODE (to) == VECTOR_TYPE
6669 && vector_types_convertible_p (to, from))
6672 if (TREE_CODE (to) == INTEGER_TYPE
6673 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6676 if (TREE_CODE (to) == FUNCTION_TYPE)
6679 if (TREE_CODE (to) != POINTER_TYPE)
6681 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6682 COMPARE_BASE | COMPARE_DERIVED);
6686 /* Return true if TO and FROM (both of which are POINTER_TYPEs or
6687 pointer-to-member types) are the same, ignoring cv-qualification at
6691 comp_ptr_ttypes_const (tree to, tree from)
6693 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6695 if (TREE_CODE (to) != TREE_CODE (from))
6698 if (TREE_CODE (from) == OFFSET_TYPE
6699 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6700 TYPE_OFFSET_BASETYPE (to)))
6703 if (TREE_CODE (to) != POINTER_TYPE)
6704 return same_type_ignoring_top_level_qualifiers_p (to, from);
6708 /* Returns the type qualifiers for this type, including the qualifiers on the
6709 elements for an array type. */
6712 cp_type_quals (tree type)
6714 type = strip_array_types (type);
6715 if (type == error_mark_node)
6716 return TYPE_UNQUALIFIED;
6717 return TYPE_QUALS (type);
6720 /* Returns nonzero if the TYPE contains a mutable member. */
6723 cp_has_mutable_p (tree type)
6725 type = strip_array_types (type);
6727 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6730 /* Apply the TYPE_QUALS to the new DECL. */
6732 cp_apply_type_quals_to_decl (int type_quals, tree decl)
6734 tree type = TREE_TYPE (decl);
6736 if (type == error_mark_node)
6739 if (TREE_CODE (type) == FUNCTION_TYPE
6740 && type_quals != TYPE_UNQUALIFIED)
6742 /* This was an error in C++98 (cv-qualifiers cannot be added to
6743 a function type), but DR 295 makes the code well-formed by
6744 dropping the extra qualifiers. */
6747 tree bad_type = build_qualified_type (type, type_quals);
6748 pedwarn ("ignoring %qV qualifiers added to function type %qT",
6752 TREE_TYPE (decl) = TYPE_MAIN_VARIANT (type);
6756 /* Avoid setting TREE_READONLY incorrectly. */
6757 if (/* If the object has a constructor, the constructor may modify
6759 TYPE_NEEDS_CONSTRUCTING (type)
6760 /* If the type isn't complete, we don't know yet if it will need
6762 || !COMPLETE_TYPE_P (type)
6763 /* If the type has a mutable component, that component might be
6765 || TYPE_HAS_MUTABLE_P (type))
6766 type_quals &= ~TYPE_QUAL_CONST;
6768 c_apply_type_quals_to_decl (type_quals, decl);
6771 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6772 exemplar types such that casting T1 to T2 is casting away constness
6773 if and only if there is no implicit conversion from T1 to T2. */
6776 casts_away_constness_r (tree *t1, tree *t2)
6781 /* [expr.const.cast]
6783 For multi-level pointer to members and multi-level mixed pointers
6784 and pointers to members (conv.qual), the "member" aspect of a
6785 pointer to member level is ignored when determining if a const
6786 cv-qualifier has been cast away. */
6787 /* [expr.const.cast]
6789 For two pointer types:
6791 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6792 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6795 casting from X1 to X2 casts away constness if, for a non-pointer
6796 type T there does not exist an implicit conversion (clause
6799 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6803 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6804 if ((!TYPE_PTR_P (*t1) && !TYPE_PTRMEM_P (*t1))
6805 || (!TYPE_PTR_P (*t2) && !TYPE_PTRMEM_P (*t2)))
6807 *t1 = cp_build_qualified_type (void_type_node,
6808 cp_type_quals (*t1));
6809 *t2 = cp_build_qualified_type (void_type_node,
6810 cp_type_quals (*t2));
6814 quals1 = cp_type_quals (*t1);
6815 quals2 = cp_type_quals (*t2);
6817 if (TYPE_PTRMEM_P (*t1))
6818 *t1 = TYPE_PTRMEM_POINTED_TO_TYPE (*t1);
6820 *t1 = TREE_TYPE (*t1);
6821 if (TYPE_PTRMEM_P (*t2))
6822 *t2 = TYPE_PTRMEM_POINTED_TO_TYPE (*t2);
6824 *t2 = TREE_TYPE (*t2);
6826 casts_away_constness_r (t1, t2);
6827 *t1 = build_pointer_type (*t1);
6828 *t2 = build_pointer_type (*t2);
6829 *t1 = cp_build_qualified_type (*t1, quals1);
6830 *t2 = cp_build_qualified_type (*t2, quals2);
6833 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6837 casts_away_constness (tree t1, tree t2)
6839 if (TREE_CODE (t2) == REFERENCE_TYPE)
6841 /* [expr.const.cast]
6843 Casting from an lvalue of type T1 to an lvalue of type T2
6844 using a reference cast casts away constness if a cast from an
6845 rvalue of type "pointer to T1" to the type "pointer to T2"
6846 casts away constness. */
6847 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6848 return casts_away_constness (build_pointer_type (t1),
6849 build_pointer_type (TREE_TYPE (t2)));
6852 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6853 /* [expr.const.cast]
6855 Casting from an rvalue of type "pointer to data member of X
6856 of type T1" to the type "pointer to data member of Y of type
6857 T2" casts away constness if a cast from an rvalue of type
6858 "pointer to T1" to the type "pointer to T2" casts away
6860 return casts_away_constness
6861 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6862 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6864 /* Casting away constness is only something that makes sense for
6865 pointer or reference types. */
6866 if (TREE_CODE (t1) != POINTER_TYPE
6867 || TREE_CODE (t2) != POINTER_TYPE)
6870 /* Top-level qualifiers don't matter. */
6871 t1 = TYPE_MAIN_VARIANT (t1);
6872 t2 = TYPE_MAIN_VARIANT (t2);
6873 casts_away_constness_r (&t1, &t2);
6874 if (!can_convert (t2, t1))
6880 /* If T is a REFERENCE_TYPE return the type to which T refers.
6881 Otherwise, return T itself. */
6884 non_reference (tree t)
6886 if (TREE_CODE (t) == REFERENCE_TYPE)
6892 /* Return nonzero if REF is an lvalue valid for this language;
6893 otherwise, print an error message and return zero. USE says
6894 how the lvalue is being used and so selects the error message. */
6897 lvalue_or_else (tree ref, enum lvalue_use use)
6899 int win = lvalue_p (ref);