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 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, 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, 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.
29 There are also routines to build RETURN_STMT nodes and CASE_STMT nodes,
30 and to process initializations in declarations (since they work
31 like a strange sort of assignment). */
35 #include "coretypes.h"
45 #include "diagnostic.h"
49 static tree convert_for_assignment (tree, tree, const char *, tree, int);
50 static tree cp_pointer_int_sum (enum tree_code, tree, tree);
51 static tree rationalize_conditional_expr (enum tree_code, tree);
52 static int comp_ptr_ttypes_real (tree, tree, int);
53 static int comp_ptr_ttypes_const (tree, tree);
54 static bool comp_except_types (tree, tree, bool);
55 static bool comp_array_types (tree, tree, bool);
56 static tree common_base_type (tree, tree);
57 static tree lookup_anon_field (tree, tree);
58 static tree pointer_diff (tree, tree, tree);
59 static tree get_delta_difference (tree, tree, int);
60 static void casts_away_constness_r (tree *, tree *);
61 static bool casts_away_constness (tree, tree);
62 static void maybe_warn_about_returning_address_of_local (tree);
63 static tree lookup_destructor (tree, tree, tree);
65 /* Return the target type of TYPE, which means return T for:
66 T*, T&, T[], T (...), and otherwise, just T. */
69 target_type (tree type)
71 type = non_reference (type);
72 while (TREE_CODE (type) == POINTER_TYPE
73 || TREE_CODE (type) == ARRAY_TYPE
74 || TREE_CODE (type) == FUNCTION_TYPE
75 || TREE_CODE (type) == METHOD_TYPE
76 || TYPE_PTRMEM_P (type))
77 type = TREE_TYPE (type);
81 /* Do `exp = require_complete_type (exp);' to make sure exp
82 does not have an incomplete type. (That includes void types.)
83 Returns the error_mark_node if the VALUE does not have
84 complete type when this function returns. */
87 require_complete_type (tree value)
91 if (processing_template_decl || value == error_mark_node)
94 if (TREE_CODE (value) == OVERLOAD)
95 type = unknown_type_node;
97 type = TREE_TYPE (value);
99 if (type == error_mark_node)
100 return error_mark_node;
102 /* First, detect a valid value with a complete type. */
103 if (COMPLETE_TYPE_P (type))
106 if (complete_type_or_else (type, value))
109 return error_mark_node;
112 /* Try to complete TYPE, if it is incomplete. For example, if TYPE is
113 a template instantiation, do the instantiation. Returns TYPE,
114 whether or not it could be completed, unless something goes
115 horribly wrong, in which case the error_mark_node is returned. */
118 complete_type (tree type)
120 if (type == NULL_TREE)
121 /* Rather than crash, we return something sure to cause an error
123 return error_mark_node;
125 if (type == error_mark_node || COMPLETE_TYPE_P (type))
127 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
129 tree t = complete_type (TREE_TYPE (type));
130 if (COMPLETE_TYPE_P (t) && ! processing_template_decl)
132 TYPE_NEEDS_CONSTRUCTING (type)
133 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
134 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
135 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
137 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
138 instantiate_class_template (TYPE_MAIN_VARIANT (type));
143 /* Like complete_type, but issue an error if the TYPE cannot be completed.
144 VALUE is used for informative diagnostics. DIAG_TYPE indicates the type
145 of diagnostic: 0 for an error, 1 for a warning, 2 for a pedwarn.
146 Returns NULL_TREE if the type cannot be made complete. */
149 complete_type_or_diagnostic (tree type, tree value, int diag_type)
151 type = complete_type (type);
152 if (type == error_mark_node)
153 /* We already issued an error. */
155 else if (!COMPLETE_TYPE_P (type))
157 cxx_incomplete_type_diagnostic (value, type, diag_type);
164 /* Return truthvalue of whether type of EXP is instantiated. */
167 type_unknown_p (tree exp)
169 return (TREE_CODE (exp) == TREE_LIST
170 || TREE_TYPE (exp) == unknown_type_node);
174 /* Return the common type of two parameter lists.
175 We assume that comptypes has already been done and returned 1;
176 if that isn't so, this may crash.
178 As an optimization, free the space we allocate if the parameter
179 lists are already common. */
182 commonparms (tree p1, tree p2)
184 tree oldargs = p1, newargs, n;
188 len = list_length (p1);
189 newargs = tree_last (p1);
191 if (newargs == void_list_node)
200 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
205 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
207 if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
209 TREE_PURPOSE (n) = TREE_PURPOSE (p1);
212 else if (! TREE_PURPOSE (p1))
214 if (TREE_PURPOSE (p2))
216 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
222 if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
224 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
226 if (TREE_VALUE (p1) != TREE_VALUE (p2))
229 TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2));
232 TREE_VALUE (n) = TREE_VALUE (p1);
240 /* Given a type, perhaps copied for a typedef,
241 find the "original" version of it. */
243 original_type (tree t)
245 while (TYPE_NAME (t) != NULL_TREE)
247 tree x = TYPE_NAME (t);
248 if (TREE_CODE (x) != TYPE_DECL)
250 x = DECL_ORIGINAL_TYPE (x);
258 /* T1 and T2 are arithmetic or enumeration types. Return the type
259 that will result from the "usual arithmetic conversions" on T1 and
260 T2 as described in [expr]. */
263 type_after_usual_arithmetic_conversions (tree t1, tree t2)
265 enum tree_code code1 = TREE_CODE (t1);
266 enum tree_code code2 = TREE_CODE (t2);
269 /* FIXME: Attributes. */
270 my_friendly_assert (ARITHMETIC_TYPE_P (t1)
271 || TREE_CODE (t1) == COMPLEX_TYPE
272 || TREE_CODE (t1) == ENUMERAL_TYPE,
274 my_friendly_assert (ARITHMETIC_TYPE_P (t2)
275 || TREE_CODE (t2) == COMPLEX_TYPE
276 || TREE_CODE (t2) == ENUMERAL_TYPE,
279 /* In what follows, we slightly generalize the rules given in [expr] so
280 as to deal with `long long' and `complex'. First, merge the
282 attributes = (*targetm.merge_type_attributes) (t1, t2);
284 /* If one type is complex, form the common type of the non-complex
285 components, then make that complex. Use T1 or T2 if it is the
287 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
289 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
290 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
292 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
294 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
295 return build_type_attribute_variant (t1, attributes);
296 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
297 return build_type_attribute_variant (t2, attributes);
299 return build_type_attribute_variant (build_complex_type (subtype),
303 /* If only one is real, use it as the result. */
304 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
305 return build_type_attribute_variant (t1, attributes);
306 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
307 return build_type_attribute_variant (t2, attributes);
309 /* Perform the integral promotions. */
310 if (code1 != REAL_TYPE)
312 t1 = type_promotes_to (t1);
313 t2 = type_promotes_to (t2);
316 /* Both real or both integers; use the one with greater precision. */
317 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
318 return build_type_attribute_variant (t1, attributes);
319 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
320 return build_type_attribute_variant (t2, attributes);
322 /* The types are the same; no need to do anything fancy. */
323 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
324 return build_type_attribute_variant (t1, attributes);
326 if (code1 != REAL_TYPE)
328 /* If one is a sizetype, use it so size_binop doesn't blow up. */
329 if (TYPE_IS_SIZETYPE (t1) > TYPE_IS_SIZETYPE (t2))
330 return build_type_attribute_variant (t1, attributes);
331 if (TYPE_IS_SIZETYPE (t2) > TYPE_IS_SIZETYPE (t1))
332 return build_type_attribute_variant (t2, attributes);
334 /* If one is unsigned long long, then convert the other to unsigned
336 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
337 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
338 return build_type_attribute_variant (long_long_unsigned_type_node,
340 /* If one is a long long, and the other is an unsigned long, and
341 long long can represent all the values of an unsigned long, then
342 convert to a long long. Otherwise, convert to an unsigned long
343 long. Otherwise, if either operand is long long, convert the
346 Since we're here, we know the TYPE_PRECISION is the same;
347 therefore converting to long long cannot represent all the values
348 of an unsigned long, so we choose unsigned long long in that
350 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
351 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
353 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
354 ? long_long_unsigned_type_node
355 : long_long_integer_type_node);
356 return build_type_attribute_variant (t, attributes);
359 /* Go through the same procedure, but for longs. */
360 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
361 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
362 return build_type_attribute_variant (long_unsigned_type_node,
364 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
365 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
367 tree t = ((TYPE_UNSIGNED (t1) || TYPE_UNSIGNED (t2))
368 ? long_unsigned_type_node : long_integer_type_node);
369 return build_type_attribute_variant (t, attributes);
371 /* Otherwise prefer the unsigned one. */
372 if (TYPE_UNSIGNED (t1))
373 return build_type_attribute_variant (t1, attributes);
375 return build_type_attribute_variant (t2, attributes);
379 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
380 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
381 return build_type_attribute_variant (long_double_type_node,
383 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
384 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
385 return build_type_attribute_variant (double_type_node,
387 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
388 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
389 return build_type_attribute_variant (float_type_node,
392 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
393 the standard C++ floating-point types. Logic earlier in this
394 function has already eliminated the possibility that
395 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
396 compelling reason to choose one or the other. */
397 return build_type_attribute_variant (t1, attributes);
401 /* Subroutine of composite_pointer_type to implement the recursive
402 case. See that function for documentation fo the parameters. */
405 composite_pointer_type_r (tree t1, tree t2, const char* location)
412 /* Determine the types pointed to by T1 and T2. */
413 if (TREE_CODE (t1) == POINTER_TYPE)
415 pointee1 = TREE_TYPE (t1);
416 pointee2 = TREE_TYPE (t2);
420 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
421 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
426 Otherwise, the composite pointer type is a pointer type
427 similar (_conv.qual_) to the type of one of the operands,
428 with a cv-qualification signature (_conv.qual_) that is the
429 union of the cv-qualification signatures of the operand
431 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
432 result_type = pointee1;
433 else if ((TREE_CODE (pointee1) == POINTER_TYPE
434 && TREE_CODE (pointee2) == POINTER_TYPE)
435 || (TYPE_PTR_TO_MEMBER_P (pointee1)
436 && TYPE_PTR_TO_MEMBER_P (pointee2)))
437 result_type = composite_pointer_type_r (pointee1, pointee2, location);
440 pedwarn ("%s between distinct pointer types `%T' and `%T' "
443 result_type = void_type_node;
445 result_type = cp_build_qualified_type (result_type,
446 (cp_type_quals (pointee1)
447 | cp_type_quals (pointee2)));
448 /* If the original types were pointers to members, so is the
450 if (TYPE_PTR_TO_MEMBER_P (t1))
452 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
453 TYPE_PTRMEM_CLASS_TYPE (t2)))
454 pedwarn ("%s between distinct pointer types `%T' and `%T' "
457 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
461 result_type = build_pointer_type (result_type);
463 /* Merge the attributes. */
464 attributes = (*targetm.merge_type_attributes) (t1, t2);
465 return build_type_attribute_variant (result_type, attributes);
468 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
469 ARG1 and ARG2 are the values with those types. The LOCATION is a
470 string describing the current location, in case an error occurs.
472 This routine also implements the computation of a common type for
473 pointers-to-members as per [expr.eq]. */
476 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
477 const char* location)
484 If one operand is a null pointer constant, the composite pointer
485 type is the type of the other operand. */
486 if (null_ptr_cst_p (arg1))
488 if (null_ptr_cst_p (arg2))
495 If one of the operands has type "pointer to cv1 void*", then
496 the other has type "pointer to cv2T", and the composite pointer
497 type is "pointer to cv12 void", where cv12 is the union of cv1
500 If either type is a pointer to void, make sure it is T1. */
501 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
509 /* Now, if T1 is a pointer to void, merge the qualifiers. */
510 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
515 if (pedantic && TYPE_PTRFN_P (t2))
516 pedwarn ("ISO C++ forbids %s between pointer of type `void *' and pointer-to-function", location);
518 = cp_build_qualified_type (void_type_node,
519 (cp_type_quals (TREE_TYPE (t1))
520 | cp_type_quals (TREE_TYPE (t2))));
521 result_type = build_pointer_type (result_type);
522 /* Merge the attributes. */
523 attributes = (*targetm.merge_type_attributes) (t1, t2);
524 return build_type_attribute_variant (result_type, attributes);
527 /* [expr.eq] permits the application of a pointer conversion to
528 bring the pointers to a common type. */
529 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
530 && CLASS_TYPE_P (TREE_TYPE (t1))
531 && CLASS_TYPE_P (TREE_TYPE (t2))
532 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
535 class1 = TREE_TYPE (t1);
536 class2 = TREE_TYPE (t2);
538 if (DERIVED_FROM_P (class1, class2))
539 t2 = (build_pointer_type
540 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
541 else if (DERIVED_FROM_P (class2, class1))
542 t1 = (build_pointer_type
543 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
546 error ("%s between distinct pointer types `%T' and `%T' "
547 "lacks a cast", location, t1, t2);
548 return error_mark_node;
551 /* [expr.eq] permits the application of a pointer-to-member
552 conversion to change the class type of one of the types. */
553 else if (TYPE_PTR_TO_MEMBER_P (t1)
554 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
555 TYPE_PTRMEM_CLASS_TYPE (t2)))
557 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
558 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
560 if (DERIVED_FROM_P (class1, class2))
561 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
562 else if (DERIVED_FROM_P (class2, class1))
563 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
566 error ("%s between distinct pointer-to-member types `%T' and `%T' "
567 "lacks a cast", location, t1, t2);
568 return error_mark_node;
572 return composite_pointer_type_r (t1, t2, location);
575 /* Return the merged type of two types.
576 We assume that comptypes has already been done and returned 1;
577 if that isn't so, this may crash.
579 This just combines attributes and default arguments; any other
580 differences would cause the two types to compare unalike. */
583 merge_types (tree t1, tree t2)
585 enum tree_code code1;
586 enum tree_code code2;
589 /* Save time if the two types are the same. */
592 if (original_type (t1) == original_type (t2))
595 /* If one type is nonsense, use the other. */
596 if (t1 == error_mark_node)
598 if (t2 == error_mark_node)
601 /* Merge the attributes. */
602 attributes = (*targetm.merge_type_attributes) (t1, t2);
604 if (TYPE_PTRMEMFUNC_P (t1))
605 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
606 if (TYPE_PTRMEMFUNC_P (t2))
607 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
609 code1 = TREE_CODE (t1);
610 code2 = TREE_CODE (t2);
616 /* For two pointers, do this recursively on the target type. */
618 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
619 int quals = cp_type_quals (t1);
621 if (code1 == POINTER_TYPE)
622 t1 = build_pointer_type (target);
624 t1 = build_reference_type (target);
625 t1 = build_type_attribute_variant (t1, attributes);
626 t1 = cp_build_qualified_type (t1, quals);
628 if (TREE_CODE (target) == METHOD_TYPE)
629 t1 = build_ptrmemfunc_type (t1);
638 quals = cp_type_quals (t1);
639 pointee = merge_types (TYPE_PTRMEM_POINTED_TO_TYPE (t1),
640 TYPE_PTRMEM_POINTED_TO_TYPE (t2));
641 t1 = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
643 t1 = cp_build_qualified_type (t1, quals);
649 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
650 /* Save space: see if the result is identical to one of the args. */
651 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
652 return build_type_attribute_variant (t1, attributes);
653 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
654 return build_type_attribute_variant (t2, attributes);
655 /* Merge the element types, and have a size if either arg has one. */
656 t1 = build_cplus_array_type
657 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
662 /* Function types: prefer the one that specified arg types.
663 If both do, merge the arg types. Also merge the return types. */
665 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
666 tree p1 = TYPE_ARG_TYPES (t1);
667 tree p2 = TYPE_ARG_TYPES (t2);
670 /* Save space: see if the result is identical to one of the args. */
671 if (valtype == TREE_TYPE (t1) && ! p2)
672 return cp_build_type_attribute_variant (t1, attributes);
673 if (valtype == TREE_TYPE (t2) && ! p1)
674 return cp_build_type_attribute_variant (t2, attributes);
676 /* Simple way if one arg fails to specify argument types. */
677 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
679 rval = build_function_type (valtype, p2);
680 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
681 rval = build_exception_variant (rval, raises);
682 return cp_build_type_attribute_variant (rval, attributes);
684 raises = TYPE_RAISES_EXCEPTIONS (t1);
685 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
687 rval = build_function_type (valtype, p1);
689 rval = build_exception_variant (rval, raises);
690 return cp_build_type_attribute_variant (rval, attributes);
693 rval = build_function_type (valtype, commonparms (p1, p2));
694 t1 = build_exception_variant (rval, raises);
700 /* Get this value the long way, since TYPE_METHOD_BASETYPE
701 is just the main variant of this. */
702 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
703 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
706 /* If this was a member function type, get back to the
707 original type of type member function (i.e., without
708 the class instance variable up front. */
709 t1 = build_function_type (TREE_TYPE (t1),
710 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
711 t2 = build_function_type (TREE_TYPE (t2),
712 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
713 t3 = merge_types (t1, t2);
714 t3 = build_method_type_directly (basetype, TREE_TYPE (t3),
715 TYPE_ARG_TYPES (t3));
716 t1 = build_exception_variant (t3, raises);
721 /* There is no need to merge attributes into a TYPENAME_TYPE.
722 When the type is instantiated it will have whatever
723 attributes result from the instantiation. */
728 return cp_build_type_attribute_variant (t1, attributes);
731 /* Return the common type of two types.
732 We assume that comptypes has already been done and returned 1;
733 if that isn't so, this may crash.
735 This is the type for the result of most arithmetic operations
736 if the operands have the given two types. */
739 common_type (tree t1, tree t2)
741 enum tree_code code1;
742 enum tree_code code2;
744 /* If one type is nonsense, bail. */
745 if (t1 == error_mark_node || t2 == error_mark_node)
746 return error_mark_node;
748 code1 = TREE_CODE (t1);
749 code2 = TREE_CODE (t2);
751 if ((ARITHMETIC_TYPE_P (t1) || code1 == ENUMERAL_TYPE
752 || code1 == COMPLEX_TYPE)
753 && (ARITHMETIC_TYPE_P (t2) || code2 == ENUMERAL_TYPE
754 || code2 == COMPLEX_TYPE))
755 return type_after_usual_arithmetic_conversions (t1, t2);
757 else if ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
758 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
759 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)))
760 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
766 /* Compare two exception specifier types for exactness or subsetness, if
767 allowed. Returns false for mismatch, true for match (same, or
770 [except.spec] "If a class X ... objects of class X or any class publicly
771 and unambiguously derived from X. Similarly, if a pointer type Y * ...
772 exceptions of type Y * or that are pointers to any type publicly and
773 unambiguously derived from Y. Otherwise a function only allows exceptions
774 that have the same type ..."
775 This does not mention cv qualifiers and is different to what throw
776 [except.throw] and catch [except.catch] will do. They will ignore the
777 top level cv qualifiers, and allow qualifiers in the pointer to class
780 We implement the letter of the standard. */
783 comp_except_types (tree a, tree b, bool exact)
785 if (same_type_p (a, b))
789 if (cp_type_quals (a) || cp_type_quals (b))
792 if (TREE_CODE (a) == POINTER_TYPE
793 && TREE_CODE (b) == POINTER_TYPE)
797 if (cp_type_quals (a) || cp_type_quals (b))
801 if (TREE_CODE (a) != RECORD_TYPE
802 || TREE_CODE (b) != RECORD_TYPE)
805 if (ACCESSIBLY_UNIQUELY_DERIVED_P (a, b))
811 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
812 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
813 otherwise it must be exact. Exception lists are unordered, but
814 we've already filtered out duplicates. Most lists will be in order,
815 we should try to make use of that. */
818 comp_except_specs (tree t1, tree t2, bool exact)
827 if (t1 == NULL_TREE) /* T1 is ... */
828 return t2 == NULL_TREE || !exact;
829 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
830 return t2 != NULL_TREE && !TREE_VALUE (t2);
831 if (t2 == NULL_TREE) /* T2 is ... */
833 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
836 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
837 Count how many we find, to determine exactness. For exact matching and
838 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
840 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
842 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
844 tree a = TREE_VALUE (probe);
845 tree b = TREE_VALUE (t2);
847 if (comp_except_types (a, b, exact))
849 if (probe == base && exact)
850 base = TREE_CHAIN (probe);
855 if (probe == NULL_TREE)
858 return !exact || base == NULL_TREE || length == list_length (t1);
861 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
862 [] can match [size]. */
865 comp_array_types (tree t1, tree t2, bool allow_redeclaration)
874 /* The type of the array elements must be the same. */
875 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
878 d1 = TYPE_DOMAIN (t1);
879 d2 = TYPE_DOMAIN (t2);
884 /* If one of the arrays is dimensionless, and the other has a
885 dimension, they are of different types. However, it is valid to
893 declarations for an array object can specify
894 array types that differ by the presence or absence of a major
895 array bound (_dcl.array_). */
897 return allow_redeclaration;
899 /* Check that the dimensions are the same. */
901 if (!cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2)))
903 max1 = TYPE_MAX_VALUE (d1);
904 max2 = TYPE_MAX_VALUE (d2);
905 if (processing_template_decl && !abi_version_at_least (2)
906 && !value_dependent_expression_p (max1)
907 && !value_dependent_expression_p (max2))
909 /* With abi-1 we do not fold non-dependent array bounds, (and
910 consequently mangle them incorrectly). We must therefore
911 fold them here, to verify the domains have the same
917 if (!cp_tree_equal (max1, max2))
923 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
924 is a bitwise-or of the COMPARE_* flags. */
927 comptypes (tree t1, tree t2, int strict)
932 /* Suppress errors caused by previously reported errors. */
933 if (t1 == error_mark_node || t2 == error_mark_node)
936 my_friendly_assert (TYPE_P (t1) && TYPE_P (t2), 20030623);
938 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
939 current instantiation. */
940 if (TREE_CODE (t1) == TYPENAME_TYPE)
942 tree resolved = resolve_typename_type (t1, /*only_current_p=*/true);
944 if (resolved != error_mark_node)
948 if (TREE_CODE (t2) == TYPENAME_TYPE)
950 tree resolved = resolve_typename_type (t2, /*only_current_p=*/true);
952 if (resolved != error_mark_node)
956 /* If either type is the internal version of sizetype, use the
958 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
959 && TYPE_ORIG_SIZE_TYPE (t1))
960 t1 = TYPE_ORIG_SIZE_TYPE (t1);
962 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
963 && TYPE_ORIG_SIZE_TYPE (t2))
964 t2 = TYPE_ORIG_SIZE_TYPE (t2);
966 if (TYPE_PTRMEMFUNC_P (t1))
967 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
968 if (TYPE_PTRMEMFUNC_P (t2))
969 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
971 /* Different classes of types can't be compatible. */
972 if (TREE_CODE (t1) != TREE_CODE (t2))
975 /* Qualifiers must match. For array types, we will check when we
976 recur on the array element types. */
977 if (TREE_CODE (t1) != ARRAY_TYPE
978 && TYPE_QUALS (t1) != TYPE_QUALS (t2))
980 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
983 /* Allow for two different type nodes which have essentially the same
984 definition. Note that we already checked for equality of the type
985 qualifiers (just above). */
987 if (TREE_CODE (t1) != ARRAY_TYPE
988 && TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
991 if (!(*targetm.comp_type_attributes) (t1, t2))
994 switch (TREE_CODE (t1))
996 case TEMPLATE_TEMPLATE_PARM:
997 case BOUND_TEMPLATE_TEMPLATE_PARM:
998 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
999 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
1001 if (!comp_template_parms
1002 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
1003 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
1005 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
1007 /* Don't check inheritance. */
1008 strict = COMPARE_STRICT;
1013 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
1014 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
1015 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
1016 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
1019 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
1021 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
1027 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
1028 strict & ~COMPARE_REDECLARATION))
1033 case REFERENCE_TYPE:
1034 return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
1038 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1040 return compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2));
1043 /* Target types must match incl. qualifiers. */
1044 return comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION));
1046 case TEMPLATE_TYPE_PARM:
1047 return (TEMPLATE_TYPE_IDX (t1) == TEMPLATE_TYPE_IDX (t2)
1048 && TEMPLATE_TYPE_LEVEL (t1) == TEMPLATE_TYPE_LEVEL (t2));
1051 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1052 TYPENAME_TYPE_FULLNAME (t2)))
1054 return same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2));
1056 case UNBOUND_CLASS_TEMPLATE:
1057 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1059 return same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2));
1062 return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
1065 return TYPE_VECTOR_SUBPARTS (t1) == TYPE_VECTOR_SUBPARTS (t2)
1066 && same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
1075 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1078 at_least_as_qualified_p (tree type1, tree type2)
1080 int q1 = cp_type_quals (type1);
1081 int q2 = cp_type_quals (type2);
1083 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1084 return (q1 & q2) == q2;
1087 /* Returns 1 if TYPE1 is more qualified than TYPE2. */
1090 more_qualified_p (tree type1, tree type2)
1092 int q1 = cp_type_quals (type1);
1093 int q2 = cp_type_quals (type2);
1095 return q1 != q2 && (q1 & q2) == q2;
1098 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1099 more cv-qualified that TYPE1, and 0 otherwise. */
1102 comp_cv_qualification (tree type1, tree type2)
1104 int q1 = cp_type_quals (type1);
1105 int q2 = cp_type_quals (type2);
1110 if ((q1 & q2) == q2)
1112 else if ((q1 & q2) == q1)
1118 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1119 subset of the cv-qualification signature of TYPE2, and the types
1120 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1123 comp_cv_qual_signature (tree type1, tree type2)
1125 if (comp_ptr_ttypes_real (type2, type1, -1))
1127 else if (comp_ptr_ttypes_real (type1, type2, -1))
1133 /* If two types share a common base type, return that basetype.
1134 If there is not a unique most-derived base type, this function
1135 returns ERROR_MARK_NODE. */
1138 common_base_type (tree tt1, tree tt2)
1140 tree best = NULL_TREE;
1143 /* If one is a baseclass of another, that's good enough. */
1144 if (UNIQUELY_DERIVED_FROM_P (tt1, tt2))
1146 if (UNIQUELY_DERIVED_FROM_P (tt2, tt1))
1149 /* Otherwise, try to find a unique baseclass of TT1
1150 that is shared by TT2, and follow that down. */
1151 for (i = CLASSTYPE_N_BASECLASSES (tt1)-1; i >= 0; i--)
1153 tree basetype = TYPE_BINFO_BASETYPE (tt1, i);
1154 tree trial = common_base_type (basetype, tt2);
1157 if (trial == error_mark_node)
1159 if (best == NULL_TREE)
1161 else if (best != trial)
1162 return error_mark_node;
1167 for (i = CLASSTYPE_N_BASECLASSES (tt2)-1; i >= 0; i--)
1169 tree basetype = TYPE_BINFO_BASETYPE (tt2, i);
1170 tree trial = common_base_type (tt1, basetype);
1173 if (trial == error_mark_node)
1175 if (best == NULL_TREE)
1177 else if (best != trial)
1178 return error_mark_node;
1184 /* Subroutines of `comptypes'. */
1186 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1187 equivalent in the sense that functions with those parameter types
1188 can have equivalent types. The two lists must be equivalent,
1189 element by element. */
1192 compparms (tree parms1, tree parms2)
1196 /* An unspecified parmlist matches any specified parmlist
1197 whose argument types don't need default promotions. */
1199 for (t1 = parms1, t2 = parms2;
1201 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1203 /* If one parmlist is shorter than the other,
1204 they fail to match. */
1207 if (!same_type_p (TREE_VALUE (t1), TREE_VALUE (t2)))
1214 /* Process a sizeof or alignof expression where the operand is a
1218 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, bool complain)
1220 enum tree_code type_code;
1222 const char *op_name;
1224 my_friendly_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR, 20020720);
1225 if (type == error_mark_node)
1226 return error_mark_node;
1228 if (processing_template_decl)
1230 value = build_min (op, size_type_node, type);
1231 TREE_READONLY (value) = 1;
1235 op_name = operator_name_info[(int) op].name;
1237 type = non_reference (type);
1238 type_code = TREE_CODE (type);
1240 if (type_code == METHOD_TYPE)
1242 if (complain && (pedantic || warn_pointer_arith))
1243 pedwarn ("invalid application of `%s' to a member function", op_name);
1244 value = size_one_node;
1247 value = c_sizeof_or_alignof_type (complete_type (type), op, complain);
1252 /* Process a sizeof or alignof expression where the operand is an
1256 cxx_sizeof_or_alignof_expr (tree e, enum tree_code op)
1258 const char *op_name = operator_name_info[(int) op].name;
1260 if (e == error_mark_node)
1261 return error_mark_node;
1263 if (processing_template_decl)
1265 e = build_min (op, size_type_node, e);
1266 TREE_SIDE_EFFECTS (e) = 0;
1267 TREE_READONLY (e) = 1;
1272 if (TREE_CODE (e) == COMPONENT_REF
1273 && TREE_CODE (TREE_OPERAND (e, 1)) == FIELD_DECL
1274 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1276 error ("invalid application of `%s' to a bit-field", op_name);
1279 else if (is_overloaded_fn (e))
1281 pedwarn ("ISO C++ forbids applying `%s' to an expression of function type", op_name);
1284 else if (type_unknown_p (e))
1286 cxx_incomplete_type_error (e, TREE_TYPE (e));
1292 return cxx_sizeof_or_alignof_type (e, op, true);
1296 /* Perform the conversions in [expr] that apply when an lvalue appears
1297 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1298 function-to-pointer conversions.
1300 In addition manifest constants are replaced by their values. */
1303 decay_conversion (tree exp)
1306 enum tree_code code;
1308 type = TREE_TYPE (exp);
1309 code = TREE_CODE (type);
1311 if (code == REFERENCE_TYPE)
1313 exp = convert_from_reference (exp);
1314 type = TREE_TYPE (exp);
1315 code = TREE_CODE (type);
1318 if (type == error_mark_node)
1319 return error_mark_node;
1321 if (type_unknown_p (exp))
1323 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1324 return error_mark_node;
1327 /* Constants can be used directly unless they're not loadable. */
1328 if (TREE_CODE (exp) == CONST_DECL)
1329 exp = DECL_INITIAL (exp);
1330 /* Replace a nonvolatile const static variable with its value. We
1331 don't do this for arrays, though; we want the address of the
1332 first element of the array, not the address of the first element
1333 of its initializing constant. */
1334 else if (code != ARRAY_TYPE)
1336 exp = decl_constant_value (exp);
1337 type = TREE_TYPE (exp);
1340 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1341 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1343 if (code == VOID_TYPE)
1345 error ("void value not ignored as it ought to be");
1346 return error_mark_node;
1348 if (code == METHOD_TYPE)
1350 error ("invalid use of non-static member function");
1351 return error_mark_node;
1353 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1354 return build_unary_op (ADDR_EXPR, exp, 0);
1355 if (code == ARRAY_TYPE)
1360 if (TREE_CODE (exp) == INDIRECT_REF)
1361 return build_nop (build_pointer_type (TREE_TYPE (type)),
1362 TREE_OPERAND (exp, 0));
1364 if (TREE_CODE (exp) == COMPOUND_EXPR)
1366 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1367 return build (COMPOUND_EXPR, TREE_TYPE (op1),
1368 TREE_OPERAND (exp, 0), op1);
1372 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1374 error ("invalid use of non-lvalue array");
1375 return error_mark_node;
1378 ptrtype = build_pointer_type (TREE_TYPE (type));
1380 if (TREE_CODE (exp) == VAR_DECL)
1382 if (!cxx_mark_addressable (exp))
1383 return error_mark_node;
1384 adr = build_nop (ptrtype, build_address (exp));
1387 /* This way is better for a COMPONENT_REF since it can
1388 simplify the offset for a component. */
1389 adr = build_unary_op (ADDR_EXPR, exp, 1);
1390 return cp_convert (ptrtype, adr);
1393 /* [basic.lval]: Class rvalues can have cv-qualified types; non-class
1394 rvalues always have cv-unqualified types. */
1395 if (! CLASS_TYPE_P (type))
1396 exp = cp_convert (TYPE_MAIN_VARIANT (type), exp);
1402 default_conversion (tree exp)
1404 exp = decay_conversion (exp);
1406 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1407 exp = perform_integral_promotions (exp);
1412 /* EXPR is an expression with an integral or enumeration type.
1413 Perform the integral promotions in [conv.prom], and return the
1417 perform_integral_promotions (tree expr)
1422 type = TREE_TYPE (expr);
1423 my_friendly_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type), 20030703);
1424 promoted_type = type_promotes_to (type);
1425 if (type != promoted_type)
1426 expr = cp_convert (promoted_type, expr);
1430 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1434 inline_conversion (tree exp)
1436 if (TREE_CODE (exp) == FUNCTION_DECL)
1437 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1442 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1443 decay_conversion to one. */
1446 string_conv_p (tree totype, tree exp, int warn)
1450 if (! flag_const_strings || TREE_CODE (totype) != POINTER_TYPE)
1453 t = TREE_TYPE (totype);
1454 if (!same_type_p (t, char_type_node)
1455 && !same_type_p (t, wchar_type_node))
1458 if (TREE_CODE (exp) == STRING_CST)
1460 /* Make sure that we don't try to convert between char and wchar_t. */
1461 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1466 /* Is this a string constant which has decayed to 'const char *'? */
1467 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1468 if (!same_type_p (TREE_TYPE (exp), t))
1471 if (TREE_CODE (exp) != ADDR_EXPR
1472 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1476 /* This warning is not very useful, as it complains about printf. */
1477 if (warn && warn_write_strings)
1478 warning ("deprecated conversion from string constant to `%T'", totype);
1483 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1484 can, for example, use as an lvalue. This code used to be in
1485 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1486 expressions, where we're dealing with aggregates. But now it's again only
1487 called from unary_complex_lvalue. The case (in particular) that led to
1488 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1492 rationalize_conditional_expr (enum tree_code code, tree t)
1494 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1495 the first operand is always the one to be used if both operands
1496 are equal, so we know what conditional expression this used to be. */
1497 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1500 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1501 ? LE_EXPR : GE_EXPR),
1502 TREE_OPERAND (t, 0),
1503 TREE_OPERAND (t, 1),
1504 /*overloaded_p=*/NULL),
1505 build_unary_op (code, TREE_OPERAND (t, 0), 0),
1506 build_unary_op (code, TREE_OPERAND (t, 1), 0));
1510 build_conditional_expr (TREE_OPERAND (t, 0),
1511 build_unary_op (code, TREE_OPERAND (t, 1), 0),
1512 build_unary_op (code, TREE_OPERAND (t, 2), 0));
1515 /* Given the TYPE of an anonymous union field inside T, return the
1516 FIELD_DECL for the field. If not found return NULL_TREE. Because
1517 anonymous unions can nest, we must also search all anonymous unions
1518 that are directly reachable. */
1521 lookup_anon_field (tree t, tree type)
1525 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1527 if (TREE_STATIC (field))
1529 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1532 /* If we find it directly, return the field. */
1533 if (DECL_NAME (field) == NULL_TREE
1534 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1539 /* Otherwise, it could be nested, search harder. */
1540 if (DECL_NAME (field) == NULL_TREE
1541 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1543 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1551 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1552 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1553 non-NULL, it indicates the path to the base used to name MEMBER.
1554 If PRESERVE_REFERENCE is true, the expression returned will have
1555 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1556 returned will have the type referred to by the reference.
1558 This function does not perform access control; that is either done
1559 earlier by the parser when the name of MEMBER is resolved to MEMBER
1560 itself, or later when overload resolution selects one of the
1561 functions indicated by MEMBER. */
1564 build_class_member_access_expr (tree object, tree member,
1565 tree access_path, bool preserve_reference)
1569 tree result = NULL_TREE;
1571 if (object == error_mark_node || member == error_mark_node)
1572 return error_mark_node;
1574 if (TREE_CODE (member) == PSEUDO_DTOR_EXPR)
1577 my_friendly_assert (DECL_P (member) || BASELINK_P (member),
1582 The type of the first expression shall be "class object" (of a
1584 object_type = TREE_TYPE (object);
1585 if (!currently_open_class (object_type)
1586 && !complete_type_or_else (object_type, object))
1587 return error_mark_node;
1588 if (!CLASS_TYPE_P (object_type))
1590 error ("request for member `%D' in `%E', which is of non-class type `%T'",
1591 member, object, object_type);
1592 return error_mark_node;
1595 /* The standard does not seem to actually say that MEMBER must be a
1596 member of OBJECT_TYPE. However, that is clearly what is
1598 if (DECL_P (member))
1600 member_scope = DECL_CLASS_CONTEXT (member);
1602 if (TREE_DEPRECATED (member))
1603 warn_deprecated_use (member);
1606 member_scope = BINFO_TYPE (BASELINK_BINFO (member));
1607 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1608 presently be the anonymous union. Go outwards until we find a
1609 type related to OBJECT_TYPE. */
1610 while (ANON_AGGR_TYPE_P (member_scope)
1611 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1613 member_scope = TYPE_CONTEXT (member_scope);
1614 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1616 if (TREE_CODE (member) == FIELD_DECL)
1617 error ("invalid use of nonstatic data member '%E'", member);
1619 error ("`%D' is not a member of `%T'", member, object_type);
1620 return error_mark_node;
1623 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1624 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1625 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1627 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1629 object = build_indirect_ref (temp, NULL);
1632 /* In [expr.ref], there is an explicit list of the valid choices for
1633 MEMBER. We check for each of those cases here. */
1634 if (TREE_CODE (member) == VAR_DECL)
1636 /* A static data member. */
1638 /* If OBJECT has side-effects, they are supposed to occur. */
1639 if (TREE_SIDE_EFFECTS (object))
1640 result = build (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1642 else if (TREE_CODE (member) == FIELD_DECL)
1644 /* A non-static data member. */
1649 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1650 && integer_zerop (TREE_OPERAND (object, 0)));
1652 /* Convert OBJECT to the type of MEMBER. */
1653 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1654 TYPE_MAIN_VARIANT (member_scope)))
1659 binfo = lookup_base (access_path ? access_path : object_type,
1660 member_scope, ba_ignore, &kind);
1661 if (binfo == error_mark_node)
1662 return error_mark_node;
1664 /* It is invalid to try to get to a virtual base of a
1665 NULL object. The most common cause is invalid use of
1667 if (null_object_p && kind == bk_via_virtual)
1669 error ("invalid access to non-static data member `%D' of NULL object",
1671 error ("(perhaps the `offsetof' macro was used incorrectly)");
1672 return error_mark_node;
1675 /* Convert to the base. */
1676 object = build_base_path (PLUS_EXPR, object, binfo,
1678 /* If we found the base successfully then we should be able
1679 to convert to it successfully. */
1680 my_friendly_assert (object != error_mark_node,
1684 /* Complain about other invalid uses of offsetof, even though they will
1685 give the right answer. Note that we complain whether or not they
1686 actually used the offsetof macro, since there's no way to know at this
1687 point. So we just give a warning, instead of a pedwarn. */
1688 if (null_object_p && warn_invalid_offsetof
1689 && CLASSTYPE_NON_POD_P (object_type))
1691 warning ("invalid access to non-static data member `%D' of NULL object",
1693 warning ("(perhaps the `offsetof' macro was used incorrectly)");
1696 /* If MEMBER is from an anonymous aggregate, we have converted
1697 OBJECT so that it refers to the class containing the
1698 anonymous union. Generate a reference to the anonymous union
1699 itself, and recur to find MEMBER. */
1700 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
1701 /* When this code is called from build_field_call, the
1702 object already has the type of the anonymous union.
1703 That is because the COMPONENT_REF was already
1704 constructed, and was then disassembled before calling
1705 build_field_call. After the function-call code is
1706 cleaned up, this waste can be eliminated. */
1707 && (!same_type_ignoring_top_level_qualifiers_p
1708 (TREE_TYPE (object), DECL_CONTEXT (member))))
1710 tree anonymous_union;
1712 anonymous_union = lookup_anon_field (TREE_TYPE (object),
1713 DECL_CONTEXT (member));
1714 object = build_class_member_access_expr (object,
1716 /*access_path=*/NULL_TREE,
1717 preserve_reference);
1720 /* Compute the type of the field, as described in [expr.ref]. */
1721 type_quals = TYPE_UNQUALIFIED;
1722 member_type = TREE_TYPE (member);
1723 if (TREE_CODE (member_type) != REFERENCE_TYPE)
1725 type_quals = (cp_type_quals (member_type)
1726 | cp_type_quals (object_type));
1728 /* A field is const (volatile) if the enclosing object, or the
1729 field itself, is const (volatile). But, a mutable field is
1730 not const, even within a const object. */
1731 if (DECL_MUTABLE_P (member))
1732 type_quals &= ~TYPE_QUAL_CONST;
1733 member_type = cp_build_qualified_type (member_type, type_quals);
1736 result = fold (build (COMPONENT_REF, member_type, object, member));
1738 /* Mark the expression const or volatile, as appropriate. Even
1739 though we've dealt with the type above, we still have to mark the
1740 expression itself. */
1741 if (type_quals & TYPE_QUAL_CONST)
1742 TREE_READONLY (result) = 1;
1743 else if (type_quals & TYPE_QUAL_VOLATILE)
1744 TREE_THIS_VOLATILE (result) = 1;
1746 else if (BASELINK_P (member))
1748 /* The member is a (possibly overloaded) member function. */
1752 /* If the MEMBER is exactly one static member function, then we
1753 know the type of the expression. Otherwise, we must wait
1754 until overload resolution has been performed. */
1755 functions = BASELINK_FUNCTIONS (member);
1756 if (TREE_CODE (functions) == FUNCTION_DECL
1757 && DECL_STATIC_FUNCTION_P (functions))
1758 type = TREE_TYPE (functions);
1760 type = unknown_type_node;
1761 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1762 base. That will happen when the function is called. */
1763 result = build (COMPONENT_REF, type, object, member);
1765 else if (TREE_CODE (member) == CONST_DECL)
1767 /* The member is an enumerator. */
1769 /* If OBJECT has side-effects, they are supposed to occur. */
1770 if (TREE_SIDE_EFFECTS (object))
1771 result = build (COMPOUND_EXPR, TREE_TYPE (result),
1776 error ("invalid use of `%D'", member);
1777 return error_mark_node;
1780 if (!preserve_reference)
1783 If E2 is declared to have type "reference to T", then ... the
1784 type of E1.E2 is T. */
1785 result = convert_from_reference (result);
1790 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1791 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1794 lookup_destructor (tree object, tree scope, tree dtor_name)
1796 tree object_type = TREE_TYPE (object);
1797 tree dtor_type = TREE_OPERAND (dtor_name, 0);
1800 if (scope && !check_dtor_name (scope, dtor_name))
1802 error ("qualified type `%T' does not match destructor name `~%T'",
1804 return error_mark_node;
1806 if (!DERIVED_FROM_P (dtor_type, TYPE_MAIN_VARIANT (object_type)))
1808 error ("the type being destroyed is `%T', but the destructor refers to `%T'",
1809 TYPE_MAIN_VARIANT (object_type), dtor_type);
1810 return error_mark_node;
1812 if (!TYPE_HAS_DESTRUCTOR (dtor_type))
1813 return build (PSEUDO_DTOR_EXPR, void_type_node, object, scope,
1815 expr = lookup_member (dtor_type, complete_dtor_identifier,
1816 /*protect=*/1, /*want_type=*/false);
1817 expr = (adjust_result_of_qualified_name_lookup
1818 (expr, dtor_type, object_type));
1822 /* This function is called by the parser to process a class member
1823 access expression of the form OBJECT.NAME. NAME is a node used by
1824 the parser to represent a name; it is not yet a DECL. It may,
1825 however, be a BASELINK where the BASELINK_FUNCTIONS is a
1826 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
1827 there is no reason to do the lookup twice, so the parser keeps the
1831 finish_class_member_access_expr (tree object, tree name)
1836 tree access_path = NULL_TREE;
1837 tree orig_object = object;
1838 tree orig_name = name;
1840 if (object == error_mark_node || name == error_mark_node)
1841 return error_mark_node;
1843 object_type = TREE_TYPE (object);
1845 if (processing_template_decl)
1847 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
1848 dependent_type_p (object_type)
1849 /* If NAME is just an IDENTIFIER_NODE, then the expression
1851 || TREE_CODE (object) == IDENTIFIER_NODE
1852 /* If NAME is "f<args>", where either 'f' or 'args' is
1853 dependent, then the expression is dependent. */
1854 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
1855 && dependent_template_id_p (TREE_OPERAND (name, 0),
1856 TREE_OPERAND (name, 1)))
1857 /* If NAME is "T::X" where "T" is dependent, then the
1858 expression is dependent. */
1859 || (TREE_CODE (name) == SCOPE_REF
1860 && TYPE_P (TREE_OPERAND (name, 0))
1861 && dependent_type_p (TREE_OPERAND (name, 0))))
1862 return build_min_nt (COMPONENT_REF, object, name);
1863 object = build_non_dependent_expr (object);
1866 if (TREE_CODE (object_type) == REFERENCE_TYPE)
1868 object = convert_from_reference (object);
1869 object_type = TREE_TYPE (object);
1874 The type of the first expression shall be "class object" (of a
1876 if (!currently_open_class (object_type)
1877 && !complete_type_or_else (object_type, object))
1878 return error_mark_node;
1879 if (!CLASS_TYPE_P (object_type))
1881 error ("request for member `%D' in `%E', which is of non-class type `%T'",
1882 name, object, object_type);
1883 return error_mark_node;
1886 if (BASELINK_P (name))
1888 /* A member function that has already been looked up. */
1889 my_friendly_assert ((TREE_CODE (BASELINK_FUNCTIONS (name))
1890 == TEMPLATE_ID_EXPR),
1896 bool is_template_id = false;
1897 tree template_args = NULL_TREE;
1900 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
1902 is_template_id = true;
1903 template_args = TREE_OPERAND (name, 1);
1904 name = TREE_OPERAND (name, 0);
1906 if (TREE_CODE (name) == OVERLOAD)
1907 name = DECL_NAME (get_first_fn (name));
1908 else if (DECL_P (name))
1909 name = DECL_NAME (name);
1912 if (TREE_CODE (name) == SCOPE_REF)
1914 /* A qualified name. The qualifying class or namespace `S' has
1915 already been looked up; it is either a TYPE or a
1916 NAMESPACE_DECL. The member name is either an IDENTIFIER_NODE
1917 or a BIT_NOT_EXPR. */
1918 scope = TREE_OPERAND (name, 0);
1919 name = TREE_OPERAND (name, 1);
1920 my_friendly_assert ((CLASS_TYPE_P (scope)
1921 || TREE_CODE (scope) == NAMESPACE_DECL),
1923 my_friendly_assert ((TREE_CODE (name) == IDENTIFIER_NODE
1924 || TREE_CODE (name) == BIT_NOT_EXPR),
1927 /* If SCOPE is a namespace, then the qualified name does not
1928 name a member of OBJECT_TYPE. */
1929 if (TREE_CODE (scope) == NAMESPACE_DECL)
1931 error ("`%D::%D' is not a member of `%T'",
1932 scope, name, object_type);
1933 return error_mark_node;
1936 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
1937 access_path = lookup_base (object_type, scope, ba_check, NULL);
1938 if (access_path == error_mark_node)
1939 return error_mark_node;
1942 error ("`%T' is not a base of `%T'", scope, object_type);
1943 return error_mark_node;
1949 access_path = object_type;
1952 if (TREE_CODE (name) == BIT_NOT_EXPR)
1953 member = lookup_destructor (object, scope, name);
1956 /* Look up the member. */
1957 member = lookup_member (access_path, name, /*protect=*/1,
1958 /*want_type=*/false);
1959 if (member == NULL_TREE)
1961 error ("'%D' has no member named '%E'", object_type, name);
1962 return error_mark_node;
1964 if (member == error_mark_node)
1965 return error_mark_node;
1970 tree template = member;
1972 if (BASELINK_P (template))
1973 template = lookup_template_function (template, template_args);
1976 error ("`%D' is not a member template function", name);
1977 return error_mark_node;
1982 if (TREE_DEPRECATED (member))
1983 warn_deprecated_use (member);
1985 expr = build_class_member_access_expr (object, member, access_path,
1986 /*preserve_reference=*/false);
1987 if (processing_template_decl && expr != error_mark_node)
1988 return build_min_non_dep (COMPONENT_REF, expr,
1989 orig_object, orig_name);
1993 /* Return an expression for the MEMBER_NAME field in the internal
1994 representation of PTRMEM, a pointer-to-member function. (Each
1995 pointer-to-member function type gets its own RECORD_TYPE so it is
1996 more convenient to access the fields by name than by FIELD_DECL.)
1997 This routine converts the NAME to a FIELD_DECL and then creates the
1998 node for the complete expression. */
2001 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
2007 /* This code is a stripped down version of
2008 build_class_member_access_expr. It does not work to use that
2009 routine directly because it expects the object to be of class
2011 ptrmem_type = TREE_TYPE (ptrmem);
2012 my_friendly_assert (TYPE_PTRMEMFUNC_P (ptrmem_type), 20020804);
2013 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
2014 /*want_type=*/false);
2015 member_type = cp_build_qualified_type (TREE_TYPE (member),
2016 cp_type_quals (ptrmem_type));
2017 return fold (build (COMPONENT_REF, member_type, ptrmem, member));
2020 /* Given an expression PTR for a pointer, return an expression
2021 for the value pointed to.
2022 ERRORSTRING is the name of the operator to appear in error messages.
2024 This function may need to overload OPERATOR_FNNAME.
2025 Must also handle REFERENCE_TYPEs for C++. */
2028 build_x_indirect_ref (tree expr, const char *errorstring)
2030 tree orig_expr = expr;
2033 if (processing_template_decl)
2035 if (type_dependent_expression_p (expr))
2036 return build_min_nt (INDIRECT_REF, expr);
2037 expr = build_non_dependent_expr (expr);
2040 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
2041 NULL_TREE, /*overloaded_p=*/NULL);
2043 rval = build_indirect_ref (expr, errorstring);
2045 if (processing_template_decl && rval != error_mark_node)
2046 return build_min_non_dep (INDIRECT_REF, rval, orig_expr);
2052 build_indirect_ref (tree ptr, const char *errorstring)
2056 if (ptr == error_mark_node)
2057 return error_mark_node;
2059 if (ptr == current_class_ptr)
2060 return current_class_ref;
2062 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
2063 ? ptr : decay_conversion (ptr));
2064 type = TREE_TYPE (pointer);
2066 if (TYPE_PTR_P (type) || TREE_CODE (type) == REFERENCE_TYPE)
2070 If the type of the expression is "pointer to T," the type
2071 of the result is "T."
2073 We must use the canonical variant because certain parts of
2074 the back end, like fold, do pointer comparisons between
2076 tree t = canonical_type_variant (TREE_TYPE (type));
2078 if (VOID_TYPE_P (t))
2080 /* A pointer to incomplete type (other than cv void) can be
2081 dereferenced [expr.unary.op]/1 */
2082 error ("`%T' is not a pointer-to-object type", type);
2083 return error_mark_node;
2085 else if (TREE_CODE (pointer) == ADDR_EXPR
2086 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2087 /* The POINTER was something like `&x'. We simplify `*&x' to
2089 return TREE_OPERAND (pointer, 0);
2092 tree ref = build1 (INDIRECT_REF, t, pointer);
2094 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2095 so that we get the proper error message if the result is used
2096 to assign to. Also, &* is supposed to be a no-op. */
2097 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2098 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2099 TREE_SIDE_EFFECTS (ref)
2100 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2104 /* `pointer' won't be an error_mark_node if we were given a
2105 pointer to member, so it's cool to check for this here. */
2106 else if (TYPE_PTR_TO_MEMBER_P (type))
2107 error ("invalid use of `%s' on pointer to member", errorstring);
2108 else if (pointer != error_mark_node)
2111 error ("invalid type argument of `%s'", errorstring);
2113 error ("invalid type argument");
2115 return error_mark_node;
2118 /* This handles expressions of the form "a[i]", which denotes
2121 This is logically equivalent in C to *(a+i), but we may do it differently.
2122 If A is a variable or a member, we generate a primitive ARRAY_REF.
2123 This avoids forcing the array out of registers, and can work on
2124 arrays that are not lvalues (for example, members of structures returned
2127 If INDEX is of some user-defined type, it must be converted to
2128 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2129 will inherit the type of the array, which will be some pointer type. */
2132 build_array_ref (tree array, tree idx)
2136 error ("subscript missing in array reference");
2137 return error_mark_node;
2140 if (TREE_TYPE (array) == error_mark_node
2141 || TREE_TYPE (idx) == error_mark_node)
2142 return error_mark_node;
2144 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2146 switch (TREE_CODE (array))
2150 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2151 return build (COMPOUND_EXPR, TREE_TYPE (value),
2152 TREE_OPERAND (array, 0), value);
2156 return build_conditional_expr
2157 (TREE_OPERAND (array, 0),
2158 build_array_ref (TREE_OPERAND (array, 1), idx),
2159 build_array_ref (TREE_OPERAND (array, 2), idx));
2165 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE)
2169 /* Subscripting with type char is likely to lose
2170 on a machine where chars are signed.
2171 So warn on any machine, but optionally.
2172 Don't warn for unsigned char since that type is safe.
2173 Don't warn for signed char because anyone who uses that
2174 must have done so deliberately. */
2175 if (warn_char_subscripts
2176 && TYPE_MAIN_VARIANT (TREE_TYPE (idx)) == char_type_node)
2177 warning ("array subscript has type `char'");
2179 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2181 error ("array subscript is not an integer");
2182 return error_mark_node;
2185 /* Apply integral promotions *after* noticing character types.
2186 (It is unclear why we do these promotions -- the standard
2187 does not say that we should. In fact, the natual thing would
2188 seem to be to convert IDX to ptrdiff_t; we're performing
2189 pointer arithmetic.) */
2190 idx = perform_integral_promotions (idx);
2192 /* An array that is indexed by a non-constant
2193 cannot be stored in a register; we must be able to do
2194 address arithmetic on its address.
2195 Likewise an array of elements of variable size. */
2196 if (TREE_CODE (idx) != INTEGER_CST
2197 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2198 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2201 if (!cxx_mark_addressable (array))
2202 return error_mark_node;
2205 /* An array that is indexed by a constant value which is not within
2206 the array bounds cannot be stored in a register either; because we
2207 would get a crash in store_bit_field/extract_bit_field when trying
2208 to access a non-existent part of the register. */
2209 if (TREE_CODE (idx) == INTEGER_CST
2210 && TYPE_DOMAIN (TREE_TYPE (array))
2211 && ! int_fits_type_p (idx, TYPE_DOMAIN (TREE_TYPE (array))))
2213 if (!cxx_mark_addressable (array))
2214 return error_mark_node;
2217 if (pedantic && !lvalue_p (array))
2218 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2220 /* Note in C++ it is valid to subscript a `register' array, since
2221 it is valid to take the address of something with that
2222 storage specification. */
2226 while (TREE_CODE (foo) == COMPONENT_REF)
2227 foo = TREE_OPERAND (foo, 0);
2228 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2229 warning ("subscripting array declared `register'");
2232 type = TREE_TYPE (TREE_TYPE (array));
2233 rval = build (ARRAY_REF, type, array, idx);
2234 /* Array ref is const/volatile if the array elements are
2235 or if the array is.. */
2236 TREE_READONLY (rval)
2237 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2238 TREE_SIDE_EFFECTS (rval)
2239 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2240 TREE_THIS_VOLATILE (rval)
2241 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2242 return require_complete_type (fold (rval));
2246 tree ar = default_conversion (array);
2247 tree ind = default_conversion (idx);
2249 /* Put the integer in IND to simplify error checking. */
2250 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2257 if (ar == error_mark_node)
2260 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2262 error ("subscripted value is neither array nor pointer");
2263 return error_mark_node;
2265 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2267 error ("array subscript is not an integer");
2268 return error_mark_node;
2271 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2276 /* Resolve a pointer to member function. INSTANCE is the object
2277 instance to use, if the member points to a virtual member.
2279 This used to avoid checking for virtual functions if basetype
2280 has no virtual functions, according to an earlier ANSI draft.
2281 With the final ISO C++ rules, such an optimization is
2282 incorrect: A pointer to a derived member can be static_cast
2283 to pointer-to-base-member, as long as the dynamic object
2284 later has the right member. */
2287 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2289 if (TREE_CODE (function) == OFFSET_REF)
2290 function = TREE_OPERAND (function, 1);
2292 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2294 tree idx, delta, e1, e2, e3, vtbl, basetype;
2295 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2297 tree instance_ptr = *instance_ptrptr;
2298 tree instance_save_expr = 0;
2299 if (instance_ptr == error_mark_node)
2301 if (TREE_CODE (function) == PTRMEM_CST)
2303 /* Extracting the function address from a pmf is only
2304 allowed with -Wno-pmf-conversions. It only works for
2306 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2307 e1 = convert (fntype, e1);
2312 error ("object missing in use of `%E'", function);
2313 return error_mark_node;
2317 if (TREE_SIDE_EFFECTS (instance_ptr))
2318 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2320 if (TREE_SIDE_EFFECTS (function))
2321 function = save_expr (function);
2323 /* Start by extracting all the information from the PMF itself. */
2324 e3 = PFN_FROM_PTRMEMFUNC (function);
2325 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2326 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2327 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2329 case ptrmemfunc_vbit_in_pfn:
2330 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2331 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2334 case ptrmemfunc_vbit_in_delta:
2335 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2336 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2343 /* Convert down to the right base before using the instance. First
2345 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2346 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2347 basetype, ba_check, NULL);
2348 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype, 1);
2349 if (instance_ptr == error_mark_node)
2350 return error_mark_node;
2351 /* ...and then the delta in the PMF. */
2352 instance_ptr = build (PLUS_EXPR, TREE_TYPE (instance_ptr),
2353 instance_ptr, delta);
2355 /* Hand back the adjusted 'this' argument to our caller. */
2356 *instance_ptrptr = instance_ptr;
2358 /* Next extract the vtable pointer from the object. */
2359 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2361 vtbl = build_indirect_ref (vtbl, NULL);
2363 /* Finally, extract the function pointer from the vtable. */
2364 e2 = fold (build (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx));
2365 e2 = build_indirect_ref (e2, NULL);
2366 TREE_CONSTANT (e2) = 1;
2367 TREE_INVARIANT (e2) = 1;
2369 /* When using function descriptors, the address of the
2370 vtable entry is treated as a function pointer. */
2371 if (TARGET_VTABLE_USES_DESCRIPTORS)
2372 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2373 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2375 TREE_TYPE (e2) = TREE_TYPE (e3);
2376 e1 = build_conditional_expr (e1, e2, e3);
2378 /* Make sure this doesn't get evaluated first inside one of the
2379 branches of the COND_EXPR. */
2380 if (instance_save_expr)
2381 e1 = build (COMPOUND_EXPR, TREE_TYPE (e1),
2382 instance_save_expr, e1);
2390 build_function_call (tree function, tree params)
2392 tree fntype, fndecl;
2393 tree coerced_params;
2395 tree name = NULL_TREE;
2397 tree original = function;
2399 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2400 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2401 if (TREE_CODE (function) == NOP_EXPR
2402 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2403 function = TREE_OPERAND (function, 0);
2405 if (TREE_CODE (function) == FUNCTION_DECL)
2407 name = DECL_NAME (function);
2409 mark_used (function);
2412 /* Convert anything with function type to a pointer-to-function. */
2413 if (pedantic && DECL_MAIN_P (function))
2414 pedwarn ("ISO C++ forbids calling `::main' from within program");
2416 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2417 (because calling an inline function does not mean the function
2418 needs to be separately compiled). */
2420 if (DECL_INLINE (function))
2421 function = inline_conversion (function);
2423 function = build_addr_func (function);
2429 function = build_addr_func (function);
2432 if (function == error_mark_node)
2433 return error_mark_node;
2435 fntype = TREE_TYPE (function);
2437 if (TYPE_PTRMEMFUNC_P (fntype))
2439 error ("must use .* or ->* to call pointer-to-member function in `%E (...)'",
2441 return error_mark_node;
2444 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2445 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2447 if (!((TREE_CODE (fntype) == POINTER_TYPE
2448 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2450 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2452 error ("`%E' cannot be used as a function", original);
2453 return error_mark_node;
2456 /* fntype now gets the type of function pointed to. */
2457 fntype = TREE_TYPE (fntype);
2459 /* Convert the parameters to the types declared in the
2460 function prototype, or apply default promotions. */
2462 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2463 params, fndecl, LOOKUP_NORMAL);
2464 if (coerced_params == error_mark_node)
2465 return error_mark_node;
2467 /* Check for errors in format strings. */
2470 check_function_format (NULL, TYPE_ATTRIBUTES (fntype), coerced_params);
2472 /* Recognize certain built-in functions so we can make tree-codes
2473 other than CALL_EXPR. We do this when it enables fold-const.c
2474 to do something useful. */
2476 if (TREE_CODE (function) == ADDR_EXPR
2477 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
2478 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
2480 result = expand_tree_builtin (TREE_OPERAND (function, 0),
2481 params, coerced_params);
2486 return build_cxx_call (function, params, coerced_params);
2489 /* Convert the actual parameter expressions in the list VALUES
2490 to the types in the list TYPELIST.
2491 If parmdecls is exhausted, or when an element has NULL as its type,
2492 perform the default conversions.
2494 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2496 This is also where warnings about wrong number of args are generated.
2498 Return a list of expressions for the parameters as converted.
2500 Both VALUES and the returned value are chains of TREE_LIST nodes
2501 with the elements of the list in the TREE_VALUE slots of those nodes.
2503 In C++, unspecified trailing parameters can be filled in with their
2504 default arguments, if such were specified. Do so here. */
2507 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2509 tree typetail, valtail;
2510 tree result = NULL_TREE;
2511 const char *called_thing = 0;
2514 /* Argument passing is always copy-initialization. */
2515 flags |= LOOKUP_ONLYCONVERTING;
2519 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2521 if (DECL_NAME (fndecl) == NULL_TREE
2522 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2523 called_thing = "constructor";
2525 called_thing = "member function";
2528 called_thing = "function";
2531 for (valtail = values, typetail = typelist;
2533 valtail = TREE_CHAIN (valtail), i++)
2535 tree type = typetail ? TREE_VALUE (typetail) : 0;
2536 tree val = TREE_VALUE (valtail);
2538 if (val == error_mark_node)
2539 return error_mark_node;
2541 if (type == void_type_node)
2545 cp_error_at ("too many arguments to %s `%+#D'", called_thing,
2547 error ("at this point in file");
2550 error ("too many arguments to function");
2551 /* In case anybody wants to know if this argument
2554 TREE_TYPE (tree_last (result)) = error_mark_node;
2558 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2559 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2560 if (TREE_CODE (val) == NOP_EXPR
2561 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2562 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2563 val = TREE_OPERAND (val, 0);
2565 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2567 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2568 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2569 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2570 val = decay_conversion (val);
2573 if (val == error_mark_node)
2574 return error_mark_node;
2578 /* Formal parm type is specified by a function prototype. */
2581 if (!COMPLETE_TYPE_P (complete_type (type)))
2584 error ("parameter %P of `%D' has incomplete type `%T'",
2587 error ("parameter %P has incomplete type `%T'", i, type);
2588 parmval = error_mark_node;
2592 parmval = convert_for_initialization
2593 (NULL_TREE, type, val, flags,
2594 "argument passing", fndecl, i);
2595 parmval = convert_for_arg_passing (type, parmval);
2598 if (parmval == error_mark_node)
2599 return error_mark_node;
2601 result = tree_cons (NULL_TREE, parmval, result);
2605 if (TREE_CODE (TREE_TYPE (val)) == REFERENCE_TYPE)
2606 val = convert_from_reference (val);
2608 if (fndecl && DECL_BUILT_IN (fndecl)
2609 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2610 /* Don't do ellipsis conversion for __built_in_constant_p
2611 as this will result in spurious warnings for non-POD
2613 val = require_complete_type (val);
2615 val = convert_arg_to_ellipsis (val);
2617 result = tree_cons (NULL_TREE, val, result);
2621 typetail = TREE_CHAIN (typetail);
2624 if (typetail != 0 && typetail != void_list_node)
2626 /* See if there are default arguments that can be used. */
2627 if (TREE_PURPOSE (typetail)
2628 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2630 for (; typetail != void_list_node; ++i)
2633 = convert_default_arg (TREE_VALUE (typetail),
2634 TREE_PURPOSE (typetail),
2637 if (parmval == error_mark_node)
2638 return error_mark_node;
2640 result = tree_cons (0, parmval, result);
2641 typetail = TREE_CHAIN (typetail);
2642 /* ends with `...'. */
2643 if (typetail == NULL_TREE)
2651 cp_error_at ("too few arguments to %s `%+#D'",
2652 called_thing, fndecl);
2653 error ("at this point in file");
2656 error ("too few arguments to function");
2657 return error_mark_list;
2661 return nreverse (result);
2664 /* Build a binary-operation expression, after performing default
2665 conversions on the operands. CODE is the kind of expression to build. */
2668 build_x_binary_op (enum tree_code code, tree arg1, tree arg2,
2678 if (processing_template_decl)
2680 if (type_dependent_expression_p (arg1)
2681 || type_dependent_expression_p (arg2))
2682 return build_min_nt (code, arg1, arg2);
2683 arg1 = build_non_dependent_expr (arg1);
2684 arg2 = build_non_dependent_expr (arg2);
2687 if (code == DOTSTAR_EXPR)
2688 expr = build_m_component_ref (arg1, arg2);
2690 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE,
2693 if (processing_template_decl && expr != error_mark_node)
2694 return build_min_non_dep (code, expr, orig_arg1, orig_arg2);
2699 /* Build a binary-operation expression without default conversions.
2700 CODE is the kind of expression to build.
2701 This function differs from `build' in several ways:
2702 the data type of the result is computed and recorded in it,
2703 warnings are generated if arg data types are invalid,
2704 special handling for addition and subtraction of pointers is known,
2705 and some optimization is done (operations on narrow ints
2706 are done in the narrower type when that gives the same result).
2707 Constant folding is also done before the result is returned.
2709 Note that the operands will never have enumeral types
2710 because either they have just had the default conversions performed
2711 or they have both just been converted to some other type in which
2712 the arithmetic is to be done.
2714 C++: must do special pointer arithmetic when implementing
2715 multiple inheritance, and deal with pointer to member functions. */
2718 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2719 int convert_p ATTRIBUTE_UNUSED)
2722 enum tree_code code0, code1;
2725 /* Expression code to give to the expression when it is built.
2726 Normally this is CODE, which is what the caller asked for,
2727 but in some special cases we change it. */
2728 enum tree_code resultcode = code;
2730 /* Data type in which the computation is to be performed.
2731 In the simplest cases this is the common type of the arguments. */
2732 tree result_type = NULL;
2734 /* Nonzero means operands have already been type-converted
2735 in whatever way is necessary.
2736 Zero means they need to be converted to RESULT_TYPE. */
2739 /* Nonzero means create the expression with this type, rather than
2741 tree build_type = 0;
2743 /* Nonzero means after finally constructing the expression
2744 convert it to this type. */
2745 tree final_type = 0;
2747 /* Nonzero if this is an operation like MIN or MAX which can
2748 safely be computed in short if both args are promoted shorts.
2749 Also implies COMMON.
2750 -1 indicates a bitwise operation; this makes a difference
2751 in the exact conditions for when it is safe to do the operation
2752 in a narrower mode. */
2755 /* Nonzero if this is a comparison operation;
2756 if both args are promoted shorts, compare the original shorts.
2757 Also implies COMMON. */
2758 int short_compare = 0;
2760 /* Nonzero if this is a right-shift operation, which can be computed on the
2761 original short and then promoted if the operand is a promoted short. */
2762 int short_shift = 0;
2764 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2767 /* Apply default conversions. */
2771 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2772 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2773 || code == TRUTH_XOR_EXPR)
2775 if (!really_overloaded_fn (op0))
2776 op0 = decay_conversion (op0);
2777 if (!really_overloaded_fn (op1))
2778 op1 = decay_conversion (op1);
2782 if (!really_overloaded_fn (op0))
2783 op0 = default_conversion (op0);
2784 if (!really_overloaded_fn (op1))
2785 op1 = default_conversion (op1);
2788 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2789 STRIP_TYPE_NOPS (op0);
2790 STRIP_TYPE_NOPS (op1);
2792 /* DTRT if one side is an overloaded function, but complain about it. */
2793 if (type_unknown_p (op0))
2795 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
2796 if (t != error_mark_node)
2798 pedwarn ("assuming cast to type `%T' from overloaded function",
2803 if (type_unknown_p (op1))
2805 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
2806 if (t != error_mark_node)
2808 pedwarn ("assuming cast to type `%T' from overloaded function",
2814 type0 = TREE_TYPE (op0);
2815 type1 = TREE_TYPE (op1);
2817 /* The expression codes of the data types of the arguments tell us
2818 whether the arguments are integers, floating, pointers, etc. */
2819 code0 = TREE_CODE (type0);
2820 code1 = TREE_CODE (type1);
2822 /* If an error was already reported for one of the arguments,
2823 avoid reporting another error. */
2825 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
2826 return error_mark_node;
2831 /* Handle the pointer + int case. */
2832 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2833 return cp_pointer_int_sum (PLUS_EXPR, op0, op1);
2834 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
2835 return cp_pointer_int_sum (PLUS_EXPR, op1, op0);
2841 /* Subtraction of two similar pointers.
2842 We must subtract them as integers, then divide by object size. */
2843 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
2844 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
2846 return pointer_diff (op0, op1, common_type (type0, type1));
2847 /* Handle pointer minus int. Just like pointer plus int. */
2848 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2849 return cp_pointer_int_sum (MINUS_EXPR, op0, op1);
2858 case TRUNC_DIV_EXPR:
2860 case FLOOR_DIV_EXPR:
2861 case ROUND_DIV_EXPR:
2862 case EXACT_DIV_EXPR:
2863 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2864 || code0 == COMPLEX_TYPE)
2865 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2866 || code1 == COMPLEX_TYPE))
2868 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
2869 warning ("division by zero in `%E / 0'", op0);
2870 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
2871 warning ("division by zero in `%E / 0.'", op0);
2873 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
2874 resultcode = RDIV_EXPR;
2876 /* When dividing two signed integers, we have to promote to int.
2877 unless we divide by a constant != -1. Note that default
2878 conversion will have been performed on the operands at this
2879 point, so we have to dig out the original type to find out if
2881 shorten = ((TREE_CODE (op0) == NOP_EXPR
2882 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2883 || (TREE_CODE (op1) == INTEGER_CST
2884 && ! integer_all_onesp (op1)));
2893 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2897 case TRUNC_MOD_EXPR:
2898 case FLOOR_MOD_EXPR:
2899 if (code1 == INTEGER_TYPE && integer_zerop (op1))
2900 warning ("division by zero in `%E %% 0'", op0);
2901 else if (code1 == REAL_TYPE && real_zerop (op1))
2902 warning ("division by zero in `%E %% 0.'", op0);
2904 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2906 /* Although it would be tempting to shorten always here, that loses
2907 on some targets, since the modulo instruction is undefined if the
2908 quotient can't be represented in the computation mode. We shorten
2909 only if unsigned or if dividing by something we know != -1. */
2910 shorten = ((TREE_CODE (op0) == NOP_EXPR
2911 && TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2912 || (TREE_CODE (op1) == INTEGER_CST
2913 && ! integer_all_onesp (op1)));
2918 case TRUTH_ANDIF_EXPR:
2919 case TRUTH_ORIF_EXPR:
2920 case TRUTH_AND_EXPR:
2922 result_type = boolean_type_node;
2925 /* Shift operations: result has same type as first operand;
2926 always convert second operand to int.
2927 Also set SHORT_SHIFT if shifting rightward. */
2930 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2932 result_type = type0;
2933 if (TREE_CODE (op1) == INTEGER_CST)
2935 if (tree_int_cst_lt (op1, integer_zero_node))
2936 warning ("right shift count is negative");
2939 if (! integer_zerop (op1))
2941 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2942 warning ("right shift count >= width of type");
2945 /* Convert the shift-count to an integer, regardless of
2946 size of value being shifted. */
2947 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2948 op1 = cp_convert (integer_type_node, op1);
2949 /* Avoid converting op1 to result_type later. */
2955 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2957 result_type = type0;
2958 if (TREE_CODE (op1) == INTEGER_CST)
2960 if (tree_int_cst_lt (op1, integer_zero_node))
2961 warning ("left shift count is negative");
2962 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2963 warning ("left shift count >= width of type");
2965 /* Convert the shift-count to an integer, regardless of
2966 size of value being shifted. */
2967 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2968 op1 = cp_convert (integer_type_node, op1);
2969 /* Avoid converting op1 to result_type later. */
2976 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2978 result_type = type0;
2979 if (TREE_CODE (op1) == INTEGER_CST)
2981 if (tree_int_cst_lt (op1, integer_zero_node))
2982 warning ("%s rotate count is negative",
2983 (code == LROTATE_EXPR) ? "left" : "right");
2984 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2985 warning ("%s rotate count >= width of type",
2986 (code == LROTATE_EXPR) ? "left" : "right");
2988 /* Convert the shift-count to an integer, regardless of
2989 size of value being shifted. */
2990 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2991 op1 = cp_convert (integer_type_node, op1);
2997 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
2998 warning ("comparing floating point with == or != is unsafe");
3000 build_type = boolean_type_node;
3001 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
3002 || code0 == COMPLEX_TYPE)
3003 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
3004 || code1 == COMPLEX_TYPE))
3006 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3007 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
3008 result_type = composite_pointer_type (type0, type1, op0, op1,
3010 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
3011 && null_ptr_cst_p (op1))
3012 result_type = type0;
3013 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
3014 && null_ptr_cst_p (op0))
3015 result_type = type1;
3016 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3018 result_type = type0;
3019 error ("ISO C++ forbids comparison between pointer and integer");
3021 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3023 result_type = type1;
3024 error ("ISO C++ forbids comparison between pointer and integer");
3026 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
3028 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
3029 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
3030 result_type = TREE_TYPE (op0);
3032 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
3033 return cp_build_binary_op (code, op1, op0);
3034 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
3035 && same_type_p (type0, type1))
3037 /* E will be the final comparison. */
3039 /* E1 and E2 are for scratch. */
3047 if (TREE_SIDE_EFFECTS (op0))
3048 op0 = save_expr (op0);
3049 if (TREE_SIDE_EFFECTS (op1))
3050 op1 = save_expr (op1);
3055 && (!op0.pfn || op0.delta == op1.delta))
3057 The reason for the `!op0.pfn' bit is that a NULL
3058 pointer-to-member is any member with a zero PFN; the
3059 DELTA field is unspecified. */
3060 pfn0 = pfn_from_ptrmemfunc (op0);
3061 pfn1 = pfn_from_ptrmemfunc (op1);
3062 delta0 = build_ptrmemfunc_access_expr (op0,
3064 delta1 = build_ptrmemfunc_access_expr (op1,
3066 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
3067 e2 = cp_build_binary_op (EQ_EXPR,
3069 cp_convert (TREE_TYPE (pfn0),
3070 integer_zero_node));
3071 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
3072 e2 = build (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3073 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3074 if (code == EQ_EXPR)
3076 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3078 else if ((TYPE_PTRMEMFUNC_P (type0)
3079 && same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0), type1))
3080 || (TYPE_PTRMEMFUNC_P (type1)
3081 && same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1), type0)))
3087 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3088 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3090 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3091 result_type = composite_pointer_type (type0, type1, op0, op1,
3099 build_type = boolean_type_node;
3100 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3101 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3103 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3104 result_type = composite_pointer_type (type0, type1, op0, op1,
3106 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3107 && integer_zerop (op1))
3108 result_type = type0;
3109 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3110 && integer_zerop (op0))
3111 result_type = type1;
3112 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3114 result_type = type0;
3115 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3117 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3119 result_type = type1;
3120 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3124 case UNORDERED_EXPR:
3131 build_type = integer_type_node;
3132 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3134 error ("unordered comparison on non-floating point argument");
3135 return error_mark_node;
3144 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3146 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
3148 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3150 if (shorten || common || short_compare)
3151 result_type = common_type (type0, type1);
3153 /* For certain operations (which identify themselves by shorten != 0)
3154 if both args were extended from the same smaller type,
3155 do the arithmetic in that type and then extend.
3157 shorten !=0 and !=1 indicates a bitwise operation.
3158 For them, this optimization is safe only if
3159 both args are zero-extended or both are sign-extended.
3160 Otherwise, we might change the result.
3161 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3162 but calculated in (unsigned short) it would be (unsigned short)-1. */
3164 if (shorten && none_complex)
3166 int unsigned0, unsigned1;
3167 tree arg0 = get_narrower (op0, &unsigned0);
3168 tree arg1 = get_narrower (op1, &unsigned1);
3169 /* UNS is 1 if the operation to be done is an unsigned one. */
3170 int uns = TYPE_UNSIGNED (result_type);
3173 final_type = result_type;
3175 /* Handle the case that OP0 does not *contain* a conversion
3176 but it *requires* conversion to FINAL_TYPE. */
3178 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3179 unsigned0 = TYPE_UNSIGNED (TREE_TYPE (op0));
3180 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3181 unsigned1 = TYPE_UNSIGNED (TREE_TYPE (op1));
3183 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3185 /* For bitwise operations, signedness of nominal type
3186 does not matter. Consider only how operands were extended. */
3190 /* Note that in all three cases below we refrain from optimizing
3191 an unsigned operation on sign-extended args.
3192 That would not be valid. */
3194 /* Both args variable: if both extended in same way
3195 from same width, do it in that width.
3196 Do it unsigned if args were zero-extended. */
3197 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3198 < TYPE_PRECISION (result_type))
3199 && (TYPE_PRECISION (TREE_TYPE (arg1))
3200 == TYPE_PRECISION (TREE_TYPE (arg0)))
3201 && unsigned0 == unsigned1
3202 && (unsigned0 || !uns))
3203 result_type = c_common_signed_or_unsigned_type
3204 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3205 else if (TREE_CODE (arg0) == INTEGER_CST
3206 && (unsigned1 || !uns)
3207 && (TYPE_PRECISION (TREE_TYPE (arg1))
3208 < TYPE_PRECISION (result_type))
3209 && (type = c_common_signed_or_unsigned_type
3210 (unsigned1, TREE_TYPE (arg1)),
3211 int_fits_type_p (arg0, type)))
3213 else if (TREE_CODE (arg1) == INTEGER_CST
3214 && (unsigned0 || !uns)
3215 && (TYPE_PRECISION (TREE_TYPE (arg0))
3216 < TYPE_PRECISION (result_type))
3217 && (type = c_common_signed_or_unsigned_type
3218 (unsigned0, TREE_TYPE (arg0)),
3219 int_fits_type_p (arg1, type)))
3223 /* Shifts can be shortened if shifting right. */
3228 tree arg0 = get_narrower (op0, &unsigned_arg);
3230 final_type = result_type;
3232 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3233 unsigned_arg = TYPE_UNSIGNED (TREE_TYPE (op0));
3235 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3236 /* We can shorten only if the shift count is less than the
3237 number of bits in the smaller type size. */
3238 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3239 /* If arg is sign-extended and then unsigned-shifted,
3240 we can simulate this with a signed shift in arg's type
3241 only if the extended result is at least twice as wide
3242 as the arg. Otherwise, the shift could use up all the
3243 ones made by sign-extension and bring in zeros.
3244 We can't optimize that case at all, but in most machines
3245 it never happens because available widths are 2**N. */
3246 && (!TYPE_UNSIGNED (final_type)
3248 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3249 <= TYPE_PRECISION (result_type))))
3251 /* Do an unsigned shift if the operand was zero-extended. */
3253 = c_common_signed_or_unsigned_type (unsigned_arg,
3255 /* Convert value-to-be-shifted to that type. */
3256 if (TREE_TYPE (op0) != result_type)
3257 op0 = cp_convert (result_type, op0);
3262 /* Comparison operations are shortened too but differently.
3263 They identify themselves by setting short_compare = 1. */
3267 /* Don't write &op0, etc., because that would prevent op0
3268 from being kept in a register.
3269 Instead, make copies of the our local variables and
3270 pass the copies by reference, then copy them back afterward. */
3271 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3272 enum tree_code xresultcode = resultcode;
3274 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3276 return cp_convert (boolean_type_node, val);
3277 op0 = xop0, op1 = xop1;
3279 resultcode = xresultcode;
3282 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3283 && warn_sign_compare
3284 /* Do not warn until the template is instantiated; we cannot
3285 bound the ranges of the arguments until that point. */
3286 && !processing_template_decl)
3288 int op0_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op0));
3289 int op1_signed = !TYPE_UNSIGNED (TREE_TYPE (orig_op1));
3291 int unsignedp0, unsignedp1;
3292 tree primop0 = get_narrower (op0, &unsignedp0);
3293 tree primop1 = get_narrower (op1, &unsignedp1);
3295 /* Check for comparison of different enum types. */
3296 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3297 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3298 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3299 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3301 warning ("comparison between types `%#T' and `%#T'",
3302 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3305 /* Give warnings for comparisons between signed and unsigned
3306 quantities that may fail. */
3307 /* Do the checking based on the original operand trees, so that
3308 casts will be considered, but default promotions won't be. */
3310 /* Do not warn if the comparison is being done in a signed type,
3311 since the signed type will only be chosen if it can represent
3312 all the values of the unsigned type. */
3313 if (!TYPE_UNSIGNED (result_type))
3315 /* Do not warn if both operands are unsigned. */
3316 else if (op0_signed == op1_signed)
3318 /* Do not warn if the signed quantity is an unsuffixed
3319 integer literal (or some static constant expression
3320 involving such literals or a conditional expression
3321 involving such literals) and it is non-negative. */
3322 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3323 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3325 /* Do not warn if the comparison is an equality operation,
3326 the unsigned quantity is an integral constant and it does
3327 not use the most significant bit of result_type. */
3328 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3329 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3330 && int_fits_type_p (orig_op1, c_common_signed_type
3332 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3333 && int_fits_type_p (orig_op0, c_common_signed_type
3337 warning ("comparison between signed and unsigned integer expressions");
3339 /* Warn if two unsigned values are being compared in a size
3340 larger than their original size, and one (and only one) is the
3341 result of a `~' operator. This comparison will always fail.
3343 Also warn if one operand is a constant, and the constant does not
3344 have all bits set that are set in the ~ operand when it is
3347 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3348 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3350 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3351 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3352 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3353 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3355 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3358 HOST_WIDE_INT constant, mask;
3362 if (host_integerp (primop0, 0))
3365 unsignedp = unsignedp1;
3366 constant = tree_low_cst (primop0, 0);
3371 unsignedp = unsignedp0;
3372 constant = tree_low_cst (primop1, 0);
3375 bits = TYPE_PRECISION (TREE_TYPE (primop));
3376 if (bits < TYPE_PRECISION (result_type)
3377 && bits < HOST_BITS_PER_LONG && unsignedp)
3379 mask = (~ (HOST_WIDE_INT) 0) << bits;
3380 if ((mask & constant) != mask)
3381 warning ("comparison of promoted ~unsigned with constant");
3384 else if (unsignedp0 && unsignedp1
3385 && (TYPE_PRECISION (TREE_TYPE (primop0))
3386 < TYPE_PRECISION (result_type))
3387 && (TYPE_PRECISION (TREE_TYPE (primop1))
3388 < TYPE_PRECISION (result_type)))
3389 warning ("comparison of promoted ~unsigned with unsigned");
3394 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
3395 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3396 Then the expression will be built.
3397 It will be given type FINAL_TYPE if that is nonzero;
3398 otherwise, it will be given type RESULT_TYPE. */
3402 error ("invalid operands of types `%T' and `%T' to binary `%O'",
3403 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3404 return error_mark_node;
3407 /* Issue warnings about peculiar, but valid, uses of NULL. */
3408 if (/* It's reasonable to use pointer values as operands of &&
3409 and ||, so NULL is no exception. */
3410 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3411 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3412 (orig_op0 == null_node
3413 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3414 /* Or vice versa. */
3415 || (orig_op1 == null_node
3416 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3417 /* Or, both are NULL and the operation was not a comparison. */
3418 || (orig_op0 == null_node && orig_op1 == null_node
3419 && code != EQ_EXPR && code != NE_EXPR)))
3420 /* Some sort of arithmetic operation involving NULL was
3421 performed. Note that pointer-difference and pointer-addition
3422 have already been handled above, and so we don't end up here in
3424 warning ("NULL used in arithmetic");
3428 if (TREE_TYPE (op0) != result_type)
3429 op0 = cp_convert (result_type, op0);
3430 if (TREE_TYPE (op1) != result_type)
3431 op1 = cp_convert (result_type, op1);
3433 if (op0 == error_mark_node || op1 == error_mark_node)
3434 return error_mark_node;
3437 if (build_type == NULL_TREE)
3438 build_type = result_type;
3441 tree result = fold (build (resultcode, build_type, op0, op1));
3442 if (final_type != 0)
3443 result = cp_convert (final_type, result);
3448 /* Return a tree for the sum or difference (RESULTCODE says which)
3449 of pointer PTROP and integer INTOP. */
3452 cp_pointer_int_sum (enum tree_code resultcode, tree ptrop, tree intop)
3454 tree res_type = TREE_TYPE (ptrop);
3456 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3457 in certain circumstance (when it's valid to do so). So we need
3458 to make sure it's complete. We don't need to check here, if we
3459 can actually complete it at all, as those checks will be done in
3460 pointer_int_sum() anyway. */
3461 complete_type (TREE_TYPE (res_type));
3463 return pointer_int_sum (resultcode, ptrop, fold (intop));
3466 /* Return a tree for the difference of pointers OP0 and OP1.
3467 The resulting tree has type int. */
3470 pointer_diff (tree op0, tree op1, tree ptrtype)
3473 tree restype = ptrdiff_type_node;
3474 tree target_type = TREE_TYPE (ptrtype);
3476 if (!complete_type_or_else (target_type, NULL_TREE))
3477 return error_mark_node;
3479 if (pedantic || warn_pointer_arith)
3481 if (TREE_CODE (target_type) == VOID_TYPE)
3482 pedwarn ("ISO C++ forbids using pointer of type `void *' in subtraction");
3483 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3484 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3485 if (TREE_CODE (target_type) == METHOD_TYPE)
3486 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3489 /* First do the subtraction as integers;
3490 then drop through to build the divide operator. */
3492 op0 = cp_build_binary_op (MINUS_EXPR,
3493 cp_convert (restype, op0),
3494 cp_convert (restype, op1));
3496 /* This generates an error if op1 is a pointer to an incomplete type. */
3497 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3498 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3500 op1 = (TYPE_PTROB_P (ptrtype)
3501 ? size_in_bytes (target_type)
3502 : integer_one_node);
3504 /* Do the division. */
3506 result = build (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3507 return fold (result);
3510 /* Construct and perhaps optimize a tree representation
3511 for a unary operation. CODE, a tree_code, specifies the operation
3512 and XARG is the operand. */
3515 build_x_unary_op (enum tree_code code, tree xarg)
3517 tree orig_expr = xarg;
3521 if (processing_template_decl)
3523 if (type_dependent_expression_p (xarg))
3524 return build_min_nt (code, xarg, NULL_TREE);
3525 xarg = build_non_dependent_expr (xarg);
3530 /* & rec, on incomplete RECORD_TYPEs is the simple opr &, not an
3532 if (code == ADDR_EXPR
3533 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3534 && ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (xarg)))
3535 && !COMPLETE_TYPE_P (TREE_TYPE (xarg)))
3536 || (TREE_CODE (xarg) == OFFSET_REF)))
3537 /* Don't look for a function. */;
3539 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE,
3540 /*overloaded_p=*/NULL);
3541 if (!exp && code == ADDR_EXPR)
3543 /* A pointer to member-function can be formed only by saying
3545 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3546 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3548 if (TREE_CODE (xarg) != OFFSET_REF)
3550 error ("invalid use of '%E' to form a pointer-to-member-function. Use a qualified-id.",
3552 return error_mark_node;
3556 error ("parenthesis around '%E' cannot be used to form a pointer-to-member-function",
3558 PTRMEM_OK_P (xarg) = 1;
3562 if (TREE_CODE (xarg) == OFFSET_REF)
3564 ptrmem = PTRMEM_OK_P (xarg);
3566 if (!ptrmem && !flag_ms_extensions
3567 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3569 /* A single non-static member, make sure we don't allow a
3570 pointer-to-member. */
3571 xarg = build (OFFSET_REF, TREE_TYPE (xarg),
3572 TREE_OPERAND (xarg, 0),
3573 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3574 PTRMEM_OK_P (xarg) = ptrmem;
3577 else if (TREE_CODE (xarg) == TARGET_EXPR)
3578 warning ("taking address of temporary");
3579 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3580 if (TREE_CODE (exp) == ADDR_EXPR)
3581 PTRMEM_OK_P (exp) = ptrmem;
3584 if (processing_template_decl && exp != error_mark_node)
3585 return build_min_non_dep (code, exp, orig_expr,
3586 /*For {PRE,POST}{INC,DEC}REMENT_EXPR*/NULL_TREE);
3590 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3591 constants, where a null value is represented by an INTEGER_CST of
3595 cp_truthvalue_conversion (tree expr)
3597 tree type = TREE_TYPE (expr);
3598 if (TYPE_PTRMEM_P (type))
3599 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3601 return c_common_truthvalue_conversion (expr);
3604 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3607 condition_conversion (tree expr)
3610 if (processing_template_decl)
3612 t = perform_implicit_conversion (boolean_type_node, expr);
3613 t = fold (build1 (CLEANUP_POINT_EXPR, boolean_type_node, t));
3617 /* Return an ADDR_EXPR giving the address of T. This function
3618 attempts no optimizations or simplifications; it is a low-level
3622 build_address (tree t)
3626 if (error_operand_p (t) || !cxx_mark_addressable (t))
3627 return error_mark_node;
3629 addr = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (t)), t);
3634 /* Return a NOP_EXPR converting EXPR to TYPE. */
3637 build_nop (tree type, tree expr)
3639 if (type == error_mark_node || error_operand_p (expr))
3641 return build1 (NOP_EXPR, type, expr);
3644 /* C++: Must handle pointers to members.
3646 Perhaps type instantiation should be extended to handle conversion
3647 from aggregates to types we don't yet know we want? (Or are those
3648 cases typically errors which should be reported?)
3650 NOCONVERT nonzero suppresses the default promotions
3651 (such as from short to int). */
3654 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3656 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3659 const char *errstring = NULL;
3662 if (arg == error_mark_node)
3663 return error_mark_node;
3668 /* This is used for unary plus, because a CONVERT_EXPR
3669 is enough to prevent anybody from looking inside for
3670 associativity, but won't generate any code. */
3671 if (!(arg = build_expr_type_conversion
3672 (WANT_ARITH | WANT_ENUM | WANT_POINTER, arg, true)))
3673 errstring = "wrong type argument to unary plus";
3677 arg = default_conversion (arg);
3678 arg = build1 (NON_LVALUE_EXPR, TREE_TYPE (arg), arg);
3683 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3684 errstring = "wrong type argument to unary minus";
3685 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3686 arg = perform_integral_promotions (arg);
3690 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3694 arg = default_conversion (arg);
3696 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
3698 errstring = "wrong type argument to bit-complement";
3699 else if (!noconvert)
3700 arg = perform_integral_promotions (arg);
3704 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3705 errstring = "wrong type argument to abs";
3706 else if (!noconvert)
3707 arg = default_conversion (arg);
3711 /* Conjugating a real value is a no-op, but allow it anyway. */
3712 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3713 errstring = "wrong type argument to conjugation";
3714 else if (!noconvert)
3715 arg = default_conversion (arg);
3718 case TRUTH_NOT_EXPR:
3719 arg = perform_implicit_conversion (boolean_type_node, arg);
3720 val = invert_truthvalue (arg);
3721 if (arg != error_mark_node)
3723 errstring = "in argument to unary !";
3730 if (TREE_CODE (arg) == COMPLEX_CST)
3731 return TREE_REALPART (arg);
3732 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3733 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
3738 if (TREE_CODE (arg) == COMPLEX_CST)
3739 return TREE_IMAGPART (arg);
3740 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3741 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
3743 return cp_convert (TREE_TYPE (arg), integer_zero_node);
3745 case PREINCREMENT_EXPR:
3746 case POSTINCREMENT_EXPR:
3747 case PREDECREMENT_EXPR:
3748 case POSTDECREMENT_EXPR:
3749 /* Handle complex lvalues (when permitted)
3750 by reduction to simpler cases. */
3752 val = unary_complex_lvalue (code, arg);
3756 /* Increment or decrement the real part of the value,
3757 and don't change the imaginary part. */
3758 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3762 arg = stabilize_reference (arg);
3763 real = build_unary_op (REALPART_EXPR, arg, 1);
3764 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
3765 return build (COMPLEX_EXPR, TREE_TYPE (arg),
3766 build_unary_op (code, real, 1), imag);
3769 /* Report invalid types. */
3771 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
3774 if (code == PREINCREMENT_EXPR)
3775 errstring ="no pre-increment operator for type";
3776 else if (code == POSTINCREMENT_EXPR)
3777 errstring ="no post-increment operator for type";
3778 else if (code == PREDECREMENT_EXPR)
3779 errstring ="no pre-decrement operator for type";
3781 errstring ="no post-decrement operator for type";
3785 /* Report something read-only. */
3787 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
3788 || TREE_READONLY (arg))
3789 readonly_error (arg, ((code == PREINCREMENT_EXPR
3790 || code == POSTINCREMENT_EXPR)
3791 ? "increment" : "decrement"),
3796 tree result_type = TREE_TYPE (arg);
3798 arg = get_unwidened (arg, 0);
3799 argtype = TREE_TYPE (arg);
3801 /* ARM $5.2.5 last annotation says this should be forbidden. */
3802 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
3803 pedwarn ("ISO C++ forbids %sing an enum",
3804 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3805 ? "increment" : "decrement");
3807 /* Compute the increment. */
3809 if (TREE_CODE (argtype) == POINTER_TYPE)
3811 tree type = complete_type (TREE_TYPE (argtype));
3813 if (!COMPLETE_OR_VOID_TYPE_P (type))
3814 error ("cannot %s a pointer to incomplete type `%T'",
3815 ((code == PREINCREMENT_EXPR
3816 || code == POSTINCREMENT_EXPR)
3817 ? "increment" : "decrement"), TREE_TYPE (argtype));
3818 else if ((pedantic || warn_pointer_arith)
3819 && !TYPE_PTROB_P (argtype))
3820 pedwarn ("ISO C++ forbids %sing a pointer of type `%T'",
3821 ((code == PREINCREMENT_EXPR
3822 || code == POSTINCREMENT_EXPR)
3823 ? "increment" : "decrement"), argtype);
3824 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
3827 inc = integer_one_node;
3829 inc = cp_convert (argtype, inc);
3831 /* Handle incrementing a cast-expression. */
3833 switch (TREE_CODE (arg))
3838 case FIX_TRUNC_EXPR:
3839 case FIX_FLOOR_EXPR:
3840 case FIX_ROUND_EXPR:
3843 tree incremented, modify, value, compound;
3844 if (! lvalue_p (arg) && pedantic)
3845 pedwarn ("cast to non-reference type used as lvalue");
3846 arg = stabilize_reference (arg);
3847 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
3850 value = save_expr (arg);
3851 incremented = build (((code == PREINCREMENT_EXPR
3852 || code == POSTINCREMENT_EXPR)
3853 ? PLUS_EXPR : MINUS_EXPR),
3854 argtype, value, inc);
3856 modify = build_modify_expr (arg, NOP_EXPR, incremented);
3857 compound = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
3859 /* Eliminate warning about unused result of + or -. */
3860 TREE_NO_WARNING (compound) = 1;
3868 /* Complain about anything else that is not a true lvalue. */
3869 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
3870 || code == POSTINCREMENT_EXPR)
3871 ? "increment" : "decrement")))
3872 return error_mark_node;
3874 /* Forbid using -- on `bool'. */
3875 if (TREE_TYPE (arg) == boolean_type_node)
3877 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
3879 error ("invalid use of `--' on bool variable `%D'", arg);
3880 return error_mark_node;
3882 val = boolean_increment (code, arg);
3885 val = build (code, TREE_TYPE (arg), arg, inc);
3887 TREE_SIDE_EFFECTS (val) = 1;
3888 return cp_convert (result_type, val);
3892 /* Note that this operation never does default_conversion
3893 regardless of NOCONVERT. */
3895 argtype = lvalue_type (arg);
3897 if (TREE_CODE (arg) == OFFSET_REF)
3900 if (TREE_CODE (argtype) == REFERENCE_TYPE)
3902 tree type = build_pointer_type (TREE_TYPE (argtype));
3903 arg = build1 (CONVERT_EXPR, type, arg);
3906 else if (pedantic && DECL_MAIN_P (arg))
3908 pedwarn ("ISO C++ forbids taking address of function `::main'");
3910 /* Let &* cancel out to simplify resulting code. */
3911 if (TREE_CODE (arg) == INDIRECT_REF)
3913 /* We don't need to have `current_class_ptr' wrapped in a
3914 NON_LVALUE_EXPR node. */
3915 if (arg == current_class_ref)
3916 return current_class_ptr;
3918 arg = TREE_OPERAND (arg, 0);
3919 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
3921 tree type = build_pointer_type (TREE_TYPE (TREE_TYPE (arg)));
3922 arg = build1 (CONVERT_EXPR, type, arg);
3924 else if (lvalue_p (arg))
3925 /* Don't let this be an lvalue. */
3926 return non_lvalue (arg);
3930 /* For &x[y], return x+y. */
3931 if (TREE_CODE (arg) == ARRAY_REF)
3933 if (!cxx_mark_addressable (TREE_OPERAND (arg, 0)))
3934 return error_mark_node;
3935 return cp_build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
3936 TREE_OPERAND (arg, 1));
3939 /* Uninstantiated types are all functions. Taking the
3940 address of a function is a no-op, so just return the
3943 if (TREE_CODE (arg) == IDENTIFIER_NODE
3944 && IDENTIFIER_OPNAME_P (arg))
3947 /* We don't know the type yet, so just work around the problem.
3948 We know that this will resolve to an lvalue. */
3949 return build1 (ADDR_EXPR, unknown_type_node, arg);
3952 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
3953 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
3955 /* They're trying to take the address of a unique non-static
3956 member function. This is ill-formed (except in MS-land),
3957 but let's try to DTRT.
3958 Note: We only handle unique functions here because we don't
3959 want to complain if there's a static overload; non-unique
3960 cases will be handled by instantiate_type. But we need to
3961 handle this case here to allow casts on the resulting PMF.
3962 We could defer this in non-MS mode, but it's easier to give
3963 a useful error here. */
3965 /* Inside constant member functions, the `this' pointer
3966 contains an extra const qualifier. TYPE_MAIN_VARIANT
3967 is used here to remove this const from the diagnostics
3968 and the created OFFSET_REF. */
3969 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
3970 tree name = DECL_NAME (get_first_fn (TREE_OPERAND (arg, 1)));
3972 if (! flag_ms_extensions)
3974 if (current_class_type
3975 && TREE_OPERAND (arg, 0) == current_class_ref)
3976 /* An expression like &memfn. */
3977 pedwarn ("ISO C++ forbids taking the address of an unqualified"
3978 " or parenthesized non-static member function to form"
3979 " a pointer to member function. Say `&%T::%D'",
3982 pedwarn ("ISO C++ forbids taking the address of a bound member"
3983 " function to form a pointer to member function."
3987 arg = build_offset_ref (base, name, /*address_p=*/true);
3991 if (type_unknown_p (arg))
3992 return build1 (ADDR_EXPR, unknown_type_node, arg);
3994 /* Handle complex lvalues (when permitted)
3995 by reduction to simpler cases. */
3996 val = unary_complex_lvalue (code, arg);
4000 switch (TREE_CODE (arg))
4005 case FIX_TRUNC_EXPR:
4006 case FIX_FLOOR_EXPR:
4007 case FIX_ROUND_EXPR:
4009 if (! lvalue_p (arg) && pedantic)
4010 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
4014 arg = OVL_CURRENT (arg);
4021 /* Allow the address of a constructor if all the elements
4023 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_HAS_CONSTRUCTOR (arg)
4024 && TREE_CONSTANT (arg))
4026 /* Anything not already handled and not a true memory reference
4028 else if (TREE_CODE (argtype) != FUNCTION_TYPE
4029 && TREE_CODE (argtype) != METHOD_TYPE
4030 && !lvalue_or_else (arg, "unary `&'"))
4031 return error_mark_node;
4033 if (argtype != error_mark_node)
4034 argtype = build_pointer_type (argtype);
4039 if (TREE_CODE (arg) != COMPONENT_REF)
4040 addr = build_address (arg);
4041 else if (TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
4043 tree fn = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
4045 /* We can only get here with a single static member
4047 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL
4048 && DECL_STATIC_FUNCTION_P (fn),
4051 addr = build_address (fn);
4052 if (TREE_SIDE_EFFECTS (TREE_OPERAND (arg, 0)))
4053 /* Do not lose object's side effects. */
4054 addr = build (COMPOUND_EXPR, TREE_TYPE (addr),
4055 TREE_OPERAND (arg, 0), addr);
4057 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
4059 error ("attempt to take address of bit-field structure member `%D'",
4060 TREE_OPERAND (arg, 1));
4061 return error_mark_node;
4065 /* Unfortunately we cannot just build an address
4066 expression here, because we would not handle
4067 address-constant-expressions or offsetof correctly. */
4068 tree field = TREE_OPERAND (arg, 1);
4069 tree rval = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
4070 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (rval)),
4071 decl_type_context (field),
4074 rval = build_base_path (PLUS_EXPR, rval, binfo, 1);
4075 rval = build_nop (argtype, rval);
4076 addr = fold (build (PLUS_EXPR, argtype, rval,
4077 cp_convert (argtype, byte_position (field))));
4080 if (TREE_CODE (argtype) == POINTER_TYPE
4081 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4083 build_ptrmemfunc_type (argtype);
4084 addr = build_ptrmemfunc (argtype, addr, 0);
4097 argtype = TREE_TYPE (arg);
4098 return fold (build1 (code, argtype, arg));
4101 error ("%s", errstring);
4102 return error_mark_node;
4105 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4106 for certain kinds of expressions which are not really lvalues
4107 but which we can accept as lvalues.
4109 If ARG is not a kind of expression we can handle, return zero. */
4112 unary_complex_lvalue (enum tree_code code, tree arg)
4114 /* Handle (a, b) used as an "lvalue". */
4115 if (TREE_CODE (arg) == COMPOUND_EXPR)
4117 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4118 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
4119 TREE_OPERAND (arg, 0), real_result);
4122 /* Handle (a ? b : c) used as an "lvalue". */
4123 if (TREE_CODE (arg) == COND_EXPR
4124 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4125 return rationalize_conditional_expr (code, arg);
4127 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4128 if (TREE_CODE (arg) == MODIFY_EXPR
4129 || TREE_CODE (arg) == PREINCREMENT_EXPR
4130 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4132 tree lvalue = TREE_OPERAND (arg, 0);
4133 if (TREE_SIDE_EFFECTS (lvalue))
4135 lvalue = stabilize_reference (lvalue);
4136 arg = build (TREE_CODE (arg), TREE_TYPE (arg),
4137 lvalue, TREE_OPERAND (arg, 1));
4139 return unary_complex_lvalue
4140 (code, build (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4143 if (code != ADDR_EXPR)
4146 /* Handle (a = b) used as an "lvalue" for `&'. */
4147 if (TREE_CODE (arg) == MODIFY_EXPR
4148 || TREE_CODE (arg) == INIT_EXPR)
4150 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4151 arg = build (COMPOUND_EXPR, TREE_TYPE (real_result), arg, real_result);
4152 TREE_NO_WARNING (arg) = 1;
4156 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4157 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4158 || TREE_CODE (arg) == OFFSET_REF)
4162 my_friendly_assert (TREE_CODE (arg) != SCOPE_REF, 313);
4164 if (TREE_CODE (arg) != OFFSET_REF)
4167 t = TREE_OPERAND (arg, 1);
4169 /* Check all this code for right semantics. */
4170 if (TREE_CODE (t) == FUNCTION_DECL)
4172 if (DECL_DESTRUCTOR_P (t))
4173 error ("taking address of destructor");
4174 return build_unary_op (ADDR_EXPR, t, 0);
4176 if (TREE_CODE (t) == VAR_DECL)
4177 return build_unary_op (ADDR_EXPR, t, 0);
4182 if (TREE_OPERAND (arg, 0)
4183 && ! is_dummy_object (TREE_OPERAND (arg, 0))
4184 && TREE_CODE (t) != FIELD_DECL)
4186 error ("taking address of bound pointer-to-member expression");
4187 return error_mark_node;
4189 if (!PTRMEM_OK_P (arg))
4190 return build_unary_op (code, arg, 0);
4192 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4194 error ("cannot create pointer to reference member `%D'", t);
4195 return error_mark_node;
4198 type = build_ptrmem_type (DECL_FIELD_CONTEXT (t), TREE_TYPE (t));
4199 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4205 /* We permit compiler to make function calls returning
4206 objects of aggregate type look like lvalues. */
4210 if (TREE_CODE (targ) == SAVE_EXPR)
4211 targ = TREE_OPERAND (targ, 0);
4213 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4215 if (TREE_CODE (arg) == SAVE_EXPR)
4218 targ = build_cplus_new (TREE_TYPE (arg), arg);
4219 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4222 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4223 return build (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4224 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4227 /* Don't let anything else be handled specially. */
4231 /* Mark EXP saying that we need to be able to take the
4232 address of it; it should not be allocated in a register.
4233 Value is true if successful.
4235 C++: we do not allow `current_class_ptr' to be addressable. */
4238 cxx_mark_addressable (tree exp)
4243 switch (TREE_CODE (x))
4250 x = TREE_OPERAND (x, 0);
4254 if (x == current_class_ptr)
4256 error ("cannot take the address of `this', which is an rvalue expression");
4257 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later. */
4263 /* Caller should not be trying to mark initialized
4264 constant fields addressable. */
4265 my_friendly_assert (DECL_LANG_SPECIFIC (x) == 0
4266 || DECL_IN_AGGR_P (x) == 0
4268 || DECL_EXTERNAL (x), 314);
4273 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4274 && !DECL_ARTIFICIAL (x) && extra_warnings)
4275 warning ("address requested for `%D', which is declared `register'",
4277 TREE_ADDRESSABLE (x) = 1;
4278 put_var_into_stack (x, /*rescan=*/true);
4282 TREE_ADDRESSABLE (x) = 1;
4283 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
4287 TREE_ADDRESSABLE (x) = 1;
4291 TREE_ADDRESSABLE (x) = 1;
4292 cxx_mark_addressable (TREE_OPERAND (x, 0));
4300 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4303 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4305 tree orig_ifexp = ifexp;
4306 tree orig_op1 = op1;
4307 tree orig_op2 = op2;
4310 if (processing_template_decl)
4312 /* The standard says that the expression is type-dependent if
4313 IFEXP is type-dependent, even though the eventual type of the
4314 expression doesn't dependent on IFEXP. */
4315 if (type_dependent_expression_p (ifexp)
4316 /* As a GNU extension, the middle operand may be omitted. */
4317 || (op1 && type_dependent_expression_p (op1))
4318 || type_dependent_expression_p (op2))
4319 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4320 ifexp = build_non_dependent_expr (ifexp);
4322 op1 = build_non_dependent_expr (op1);
4323 op2 = build_non_dependent_expr (op2);
4326 expr = build_conditional_expr (ifexp, op1, op2);
4327 if (processing_template_decl && expr != error_mark_node)
4328 return build_min_non_dep (COND_EXPR, expr,
4329 orig_ifexp, orig_op1, orig_op2);
4333 /* Given a list of expressions, return a compound expression
4334 that performs them all and returns the value of the last of them. */
4336 tree build_x_compound_expr_from_list (tree list, const char *msg)
4338 tree expr = TREE_VALUE (list);
4340 if (TREE_CHAIN (list))
4343 pedwarn ("%s expression list treated as compound expression", msg);
4345 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4346 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4352 /* Handle overloading of the ',' operator when needed. */
4355 build_x_compound_expr (tree op1, tree op2)
4358 tree orig_op1 = op1;
4359 tree orig_op2 = op2;
4361 if (processing_template_decl)
4363 if (type_dependent_expression_p (op1)
4364 || type_dependent_expression_p (op2))
4365 return build_min_nt (COMPOUND_EXPR, op1, op2);
4366 op1 = build_non_dependent_expr (op1);
4367 op2 = build_non_dependent_expr (op2);
4370 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE,
4371 /*overloaded_p=*/NULL);
4373 result = build_compound_expr (op1, op2);
4375 if (processing_template_decl && result != error_mark_node)
4376 return build_min_non_dep (COMPOUND_EXPR, result, orig_op1, orig_op2);
4381 /* Build a compound expression. */
4384 build_compound_expr (tree lhs, tree rhs)
4386 lhs = decl_constant_value (lhs);
4387 lhs = convert_to_void (lhs, "left-hand operand of comma");
4389 if (lhs == error_mark_node || rhs == error_mark_node)
4390 return error_mark_node;
4392 if (TREE_CODE (rhs) == TARGET_EXPR)
4394 /* If the rhs is a TARGET_EXPR, then build the compound
4395 expression inside the target_expr's initializer. This
4396 helps the compiler to eliminate unnecessary temporaries. */
4397 tree init = TREE_OPERAND (rhs, 1);
4399 init = build (COMPOUND_EXPR, TREE_TYPE (init), lhs, init);
4400 TREE_OPERAND (rhs, 1) = init;
4405 return build (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4408 /* Issue an error message if casting from SRC_TYPE to DEST_TYPE casts
4409 away constness. DESCRIPTION explains what operation is taking
4413 check_for_casting_away_constness (tree src_type, tree dest_type,
4414 const char *description)
4416 if (casts_away_constness (src_type, dest_type))
4417 error ("%s from type `%T' to type `%T' casts away constness",
4418 description, src_type, dest_type);
4421 /* Return an expression representing static_cast<TYPE>(EXPR). */
4424 build_static_cast (tree type, tree expr)
4429 if (type == error_mark_node || expr == error_mark_node)
4430 return error_mark_node;
4432 if (processing_template_decl)
4434 expr = build_min (STATIC_CAST_EXPR, type, expr);
4435 /* We don't know if it will or will not have side effects. */
4436 TREE_SIDE_EFFECTS (expr) = 1;
4440 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4441 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4442 if (TREE_CODE (type) != REFERENCE_TYPE
4443 && TREE_CODE (expr) == NOP_EXPR
4444 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4445 expr = TREE_OPERAND (expr, 0);
4447 intype = TREE_TYPE (expr);
4449 /* [expr.static.cast]
4451 An lvalue of type "cv1 B", where B is a class type, can be cast
4452 to type "reference to cv2 D", where D is a class derived (clause
4453 _class.derived_) from B, if a valid standard conversion from
4454 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4455 same cv-qualification as, or greater cv-qualification than, cv1,
4456 and B is not a virtual base class of D. */
4457 /* We check this case before checking the validity of "TYPE t =
4458 EXPR;" below because for this case:
4461 struct D : public B { D(const B&); };
4463 void f() { static_cast<const D&>(b); }
4465 we want to avoid constructing a new D. The standard is not
4466 completely clear about this issue, but our interpretation is
4467 consistent with other compilers. */
4468 if (TREE_CODE (type) == REFERENCE_TYPE
4469 && CLASS_TYPE_P (TREE_TYPE (type))
4470 && CLASS_TYPE_P (intype)
4471 && real_lvalue_p (expr)
4472 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4473 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4474 build_pointer_type (TYPE_MAIN_VARIANT
4475 (TREE_TYPE (type))))
4476 && at_least_as_qualified_p (TREE_TYPE (type), intype))
4478 /* There is a standard conversion from "D*" to "B*" even if "B"
4479 is ambiguous or inaccessible. Therefore, we ask lookup_base
4480 to check these conditions. */
4481 tree base = lookup_base (TREE_TYPE (type), intype, ba_check, NULL);
4483 /* Convert from "B*" to "D*". This function will check that "B"
4484 is not a virtual base of "D". */
4485 expr = build_base_path (MINUS_EXPR, build_address (expr),
4486 base, /*nonnull=*/false);
4487 /* Convert the pointer to a reference -- but then remember that
4488 there are no expressions with reference type in C++. */
4489 return convert_from_reference (build_nop (type, expr));
4492 /* [expr.static.cast]
4494 An expression e can be explicitly converted to a type T using a
4495 static_cast of the form static_cast<T>(e) if the declaration T
4496 t(e);" is well-formed, for some invented temporary variable
4498 result = perform_direct_initialization_if_possible (type, expr);
4500 return convert_from_reference (result);
4502 /* [expr.static.cast]
4504 Any expression can be explicitly converted to type cv void. */
4505 if (TREE_CODE (type) == VOID_TYPE)
4506 return convert_to_void (expr, /*implicit=*/NULL);
4508 /* [expr.static.cast]
4510 The inverse of any standard conversion sequence (clause _conv_),
4511 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4512 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4513 (_conv.bool_) conversions, can be performed explicitly using
4514 static_cast subject to the restriction that the explicit
4515 conversion does not cast away constness (_expr.const.cast_), and
4516 the following additional rules for specific cases: */
4517 /* For reference, the conversions not excluded are: integral
4518 promotions, floating point promotion, integral conversions,
4519 floating point conversions, floating-integral conversions,
4520 pointer conversions, and pointer to member conversions. */
4521 if ((ARITHMETIC_TYPE_P (type) && ARITHMETIC_TYPE_P (intype))
4524 A value of integral _or enumeration_ type can be explicitly
4525 converted to an enumeration type. */
4526 || (INTEGRAL_OR_ENUMERATION_TYPE_P (type)
4527 && INTEGRAL_OR_ENUMERATION_TYPE_P (intype)))
4528 /* Really, build_c_cast should defer to this function rather
4529 than the other way around. */
4530 return build_c_cast (type, expr);
4532 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4533 && CLASS_TYPE_P (TREE_TYPE (type))
4534 && CLASS_TYPE_P (TREE_TYPE (intype))
4535 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4536 (TREE_TYPE (intype))),
4537 build_pointer_type (TYPE_MAIN_VARIANT
4538 (TREE_TYPE (type)))))
4542 check_for_casting_away_constness (intype, type, "static_cast");
4543 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype), ba_check,
4545 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4548 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4549 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4556 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4557 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4559 if (TYPE_PTRMEM_P (type))
4561 t1 = (build_ptrmem_type
4563 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4564 t2 = (build_ptrmem_type
4566 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4573 if (can_convert (t1, t2))
4575 check_for_casting_away_constness (intype, type, "static_cast");
4576 if (TYPE_PTRMEM_P (type))
4580 if (TREE_CODE (expr) == PTRMEM_CST)
4581 expr = cplus_expand_constant (expr);
4582 delta = get_delta_difference (c1, c2, /*force=*/1);
4583 if (!integer_zerop (delta))
4584 expr = cp_build_binary_op (PLUS_EXPR,
4585 build_nop (ptrdiff_type_node, expr),
4587 return build_nop (type, expr);
4590 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4595 /* [expr.static.cast]
4597 An rvalue of type "pointer to cv void" can be explicitly
4598 converted to a pointer to object type. A value of type pointer
4599 to object converted to "pointer to cv void" and back to the
4600 original pointer type will have its original value. */
4601 if (TREE_CODE (intype) == POINTER_TYPE
4602 && VOID_TYPE_P (TREE_TYPE (intype))
4603 && TYPE_PTROB_P (type))
4605 check_for_casting_away_constness (intype, type, "static_cast");
4606 return build_nop (type, expr);
4609 error ("invalid static_cast from type `%T' to type `%T'", intype, type);
4610 return error_mark_node;
4614 build_reinterpret_cast (tree type, tree expr)
4618 if (type == error_mark_node || expr == error_mark_node)
4619 return error_mark_node;
4621 if (processing_template_decl)
4623 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
4625 if (!TREE_SIDE_EFFECTS (t)
4626 && type_dependent_expression_p (expr))
4627 /* There might turn out to be side effects inside expr. */
4628 TREE_SIDE_EFFECTS (t) = 1;
4632 if (TREE_CODE (type) != REFERENCE_TYPE)
4634 expr = decay_conversion (expr);
4636 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4637 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4638 if (TREE_CODE (expr) == NOP_EXPR
4639 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4640 expr = TREE_OPERAND (expr, 0);
4643 intype = TREE_TYPE (expr);
4645 if (TREE_CODE (type) == REFERENCE_TYPE)
4647 if (! real_lvalue_p (expr))
4649 error ("invalid reinterpret_cast of an rvalue expression of type `%T' to type `%T'", intype, type);
4650 return error_mark_node;
4652 expr = build_unary_op (ADDR_EXPR, expr, 0);
4653 if (expr != error_mark_node)
4654 expr = build_reinterpret_cast
4655 (build_pointer_type (TREE_TYPE (type)), expr);
4656 if (expr != error_mark_node)
4657 expr = build_indirect_ref (expr, 0);
4660 else if (same_type_ignoring_top_level_qualifiers_p (intype, type))
4661 return build_static_cast (type, expr);
4663 if (TYPE_PTR_P (type) && (TREE_CODE (intype) == INTEGER_TYPE
4664 || TREE_CODE (intype) == ENUMERAL_TYPE))
4666 else if (TREE_CODE (type) == INTEGER_TYPE && TYPE_PTR_P (intype))
4668 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
4669 pedwarn ("reinterpret_cast from `%T' to `%T' loses precision",
4672 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
4673 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4675 expr = decl_constant_value (expr);
4676 return fold (build1 (NOP_EXPR, type, expr));
4678 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4679 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
4681 check_for_casting_away_constness (intype, type, "reinterpret_cast");
4682 expr = decl_constant_value (expr);
4683 return fold (build1 (NOP_EXPR, type, expr));
4685 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
4686 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
4688 pedwarn ("ISO C++ forbids casting between pointer-to-function and pointer-to-object");
4689 expr = decl_constant_value (expr);
4690 return fold (build1 (NOP_EXPR, type, expr));
4694 error ("invalid reinterpret_cast from type `%T' to type `%T'",
4696 return error_mark_node;
4699 return cp_convert (type, expr);
4703 build_const_cast (tree type, tree expr)
4707 if (type == error_mark_node || expr == error_mark_node)
4708 return error_mark_node;
4710 if (processing_template_decl)
4712 tree t = build_min (CONST_CAST_EXPR, type, expr);
4714 if (!TREE_SIDE_EFFECTS (t)
4715 && type_dependent_expression_p (expr))
4716 /* There might turn out to be side effects inside expr. */
4717 TREE_SIDE_EFFECTS (t) = 1;
4721 if (!POINTER_TYPE_P (type) && !TYPE_PTRMEM_P (type))
4722 error ("invalid use of const_cast with type `%T', which is not a pointer, reference, nor a pointer-to-data-member type", type);
4723 else if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
4725 error ("invalid use of const_cast with type `%T', which is a pointer or reference to a function type", type);
4726 return error_mark_node;
4729 if (TREE_CODE (type) != REFERENCE_TYPE)
4731 expr = decay_conversion (expr);
4733 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4734 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4735 if (TREE_CODE (expr) == NOP_EXPR
4736 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4737 expr = TREE_OPERAND (expr, 0);
4740 intype = TREE_TYPE (expr);
4742 if (same_type_ignoring_top_level_qualifiers_p (intype, type))
4743 return build_static_cast (type, expr);
4744 else if (TREE_CODE (type) == REFERENCE_TYPE)
4746 if (! real_lvalue_p (expr))
4748 error ("invalid const_cast of an rvalue of type `%T' to type `%T'", intype, type);
4749 return error_mark_node;
4752 if (comp_ptr_ttypes_const (TREE_TYPE (type), intype))
4754 expr = build_unary_op (ADDR_EXPR, expr, 0);
4755 expr = build1 (NOP_EXPR, type, expr);
4756 return convert_from_reference (expr);
4759 else if (((TREE_CODE (type) == POINTER_TYPE
4760 && TREE_CODE (intype) == POINTER_TYPE)
4761 || (TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype)))
4762 && comp_ptr_ttypes_const (TREE_TYPE (type), TREE_TYPE (intype)))
4763 return cp_convert (type, expr);
4765 error ("invalid const_cast from type `%T' to type `%T'", intype, type);
4766 return error_mark_node;
4769 /* Build an expression representing a cast to type TYPE of expression EXPR.
4771 ALLOW_NONCONVERTING is true if we should allow non-converting constructors
4772 when doing the cast. */
4775 build_c_cast (tree type, tree expr)
4780 if (type == error_mark_node || expr == error_mark_node)
4781 return error_mark_node;
4783 if (processing_template_decl)
4785 tree t = build_min (CAST_EXPR, type,
4786 tree_cons (NULL_TREE, value, NULL_TREE));
4787 /* We don't know if it will or will not have side effects. */
4788 TREE_SIDE_EFFECTS (t) = 1;
4792 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4793 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4794 if (TREE_CODE (type) != REFERENCE_TYPE
4795 && TREE_CODE (value) == NOP_EXPR
4796 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
4797 value = TREE_OPERAND (value, 0);
4799 if (TREE_CODE (type) == ARRAY_TYPE)
4801 /* Allow casting from T1* to T2[] because Cfront allows it.
4802 NIHCL uses it. It is not valid ISO C++ however. */
4803 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
4805 pedwarn ("ISO C++ forbids casting to an array type `%T'", type);
4806 type = build_pointer_type (TREE_TYPE (type));
4810 error ("ISO C++ forbids casting to an array type `%T'", type);
4811 return error_mark_node;
4815 if (TREE_CODE (type) == FUNCTION_TYPE
4816 || TREE_CODE (type) == METHOD_TYPE)
4818 error ("invalid cast to function type `%T'", type);
4819 return error_mark_node;
4822 if (TREE_CODE (type) == VOID_TYPE)
4824 /* Conversion to void does not cause any of the normal function to
4825 * pointer, array to pointer and lvalue to rvalue decays. */
4827 value = convert_to_void (value, /*implicit=*/NULL);
4831 if (!complete_type_or_else (type, NULL_TREE))
4832 return error_mark_node;
4834 /* Convert functions and arrays to pointers and
4835 convert references to their expanded types,
4836 but don't convert any other types. If, however, we are
4837 casting to a class type, there's no reason to do this: the
4838 cast will only succeed if there is a converting constructor,
4839 and the default conversions will be done at that point. In
4840 fact, doing the default conversion here is actually harmful
4844 struct S { S(const A&); };
4846 since we don't want the array-to-pointer conversion done. */
4847 if (!IS_AGGR_TYPE (type))
4849 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
4850 || (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE
4851 /* Don't do the default conversion on a ->* expression. */
4852 && ! (TREE_CODE (type) == POINTER_TYPE
4853 && bound_pmf_p (value)))
4854 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
4855 || TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
4856 value = decay_conversion (value);
4858 else if (TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
4859 /* However, even for class types, we still need to strip away
4860 the reference type, since the call to convert_force below
4861 does not expect the input expression to be of reference
4863 value = convert_from_reference (value);
4865 otype = TREE_TYPE (value);
4867 /* Optionally warn about potentially worrisome casts. */
4870 && TREE_CODE (type) == POINTER_TYPE
4871 && TREE_CODE (otype) == POINTER_TYPE
4872 && !at_least_as_qualified_p (TREE_TYPE (type),
4874 warning ("cast from `%T' to `%T' discards qualifiers from pointer target type",
4877 if (TREE_CODE (type) == INTEGER_TYPE
4878 && TYPE_PTR_P (otype)
4879 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
4880 warning ("cast from pointer to integer of different size");
4882 if (TYPE_PTR_P (type)
4883 && TREE_CODE (otype) == INTEGER_TYPE
4884 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
4885 /* Don't warn about converting any constant. */
4886 && !TREE_CONSTANT (value))
4887 warning ("cast to pointer from integer of different size");
4889 if (TREE_CODE (type) == REFERENCE_TYPE)
4890 value = (convert_from_reference
4891 (convert_to_reference (type, value, CONV_C_CAST,
4892 LOOKUP_COMPLAIN, NULL_TREE)));
4897 value = decl_constant_value (value);
4900 value = convert_force (type, value, CONV_C_CAST);
4902 /* Ignore any integer overflow caused by the cast. */
4903 if (TREE_CODE (value) == INTEGER_CST)
4905 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
4907 if (TREE_CODE_CLASS (TREE_CODE (ovalue)) == 'c')
4908 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
4912 /* Warn about possible alignment problems. Do this here when we will have
4913 instantiated any necessary template types. */
4914 if (STRICT_ALIGNMENT && warn_cast_align
4915 && TREE_CODE (type) == POINTER_TYPE
4916 && TREE_CODE (otype) == POINTER_TYPE
4917 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
4918 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
4919 && COMPLETE_TYPE_P (TREE_TYPE (otype))
4920 && COMPLETE_TYPE_P (TREE_TYPE (type))
4921 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
4922 warning ("cast from `%T' to `%T' increases required alignment of target type",
4925 /* Always produce some operator for an explicit cast,
4926 so we can tell (for -pedantic) that the cast is no lvalue. */
4927 if (TREE_CODE (type) != REFERENCE_TYPE && value == expr
4928 && real_lvalue_p (value))
4929 value = non_lvalue (value);
4934 /* Build an assignment expression of lvalue LHS from value RHS.
4935 MODIFYCODE is the code for a binary operator that we use
4936 to combine the old value of LHS with RHS to get the new value.
4937 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
4939 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
4942 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
4946 tree lhstype = TREE_TYPE (lhs);
4947 tree olhstype = lhstype;
4948 tree olhs = NULL_TREE;
4950 /* Avoid duplicate error messages from operands that had errors. */
4951 if (lhs == error_mark_node || rhs == error_mark_node)
4952 return error_mark_node;
4954 /* Handle control structure constructs used as "lvalues". */
4955 switch (TREE_CODE (lhs))
4957 /* Handle --foo = 5; as these are valid constructs in C++. */
4958 case PREDECREMENT_EXPR:
4959 case PREINCREMENT_EXPR:
4960 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
4961 lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
4962 stabilize_reference (TREE_OPERAND (lhs, 0)),
4963 TREE_OPERAND (lhs, 1));
4964 return build (COMPOUND_EXPR, lhstype,
4966 build_modify_expr (TREE_OPERAND (lhs, 0),
4969 /* Handle (a, b) used as an "lvalue". */
4971 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
4973 if (newrhs == error_mark_node)
4974 return error_mark_node;
4975 return build (COMPOUND_EXPR, lhstype,
4976 TREE_OPERAND (lhs, 0), newrhs);
4979 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
4980 lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
4981 stabilize_reference (TREE_OPERAND (lhs, 0)),
4982 TREE_OPERAND (lhs, 1));
4983 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
4984 if (newrhs == error_mark_node)
4985 return error_mark_node;
4986 return build (COMPOUND_EXPR, lhstype, lhs, newrhs);
4988 /* Handle (a ? b : c) used as an "lvalue". */
4991 /* Produce (a ? (b = rhs) : (c = rhs))
4992 except that the RHS goes through a save-expr
4993 so the code to compute it is only emitted once. */
4995 tree preeval = NULL_TREE;
4997 rhs = stabilize_expr (rhs, &preeval);
4999 /* Check this here to avoid odd errors when trying to convert
5000 a throw to the type of the COND_EXPR. */
5001 if (!lvalue_or_else (lhs, "assignment"))
5002 return error_mark_node;
5004 cond = build_conditional_expr
5005 (TREE_OPERAND (lhs, 0),
5006 build_modify_expr (cp_convert (TREE_TYPE (lhs),
5007 TREE_OPERAND (lhs, 1)),
5009 build_modify_expr (cp_convert (TREE_TYPE (lhs),
5010 TREE_OPERAND (lhs, 2)),
5013 if (cond == error_mark_node)
5015 /* Make sure the code to compute the rhs comes out
5016 before the split. */
5018 cond = build (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
5026 if (modifycode == INIT_EXPR)
5028 if (TREE_CODE (rhs) == CONSTRUCTOR)
5030 if (! same_type_p (TREE_TYPE (rhs), lhstype))
5031 /* Call convert to generate an error; see PR 11063. */
5032 rhs = convert (lhstype, rhs);
5033 result = build (INIT_EXPR, lhstype, lhs, rhs);
5034 TREE_SIDE_EFFECTS (result) = 1;
5037 else if (! IS_AGGR_TYPE (lhstype))
5038 /* Do the default thing. */;
5041 result = build_special_member_call (lhs, complete_ctor_identifier,
5042 build_tree_list (NULL_TREE, rhs),
5043 TYPE_BINFO (lhstype),
5045 if (result == NULL_TREE)
5046 return error_mark_node;
5052 if (TREE_CODE (lhstype) == REFERENCE_TYPE)
5054 lhs = convert_from_reference (lhs);
5055 olhstype = lhstype = TREE_TYPE (lhs);
5057 lhs = require_complete_type (lhs);
5058 if (lhs == error_mark_node)
5059 return error_mark_node;
5061 if (modifycode == NOP_EXPR)
5063 /* `operator=' is not an inheritable operator. */
5064 if (! IS_AGGR_TYPE (lhstype))
5065 /* Do the default thing. */;
5068 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
5069 lhs, rhs, make_node (NOP_EXPR),
5070 /*overloaded_p=*/NULL);
5071 if (result == NULL_TREE)
5072 return error_mark_node;
5079 /* A binary op has been requested. Combine the old LHS
5080 value with the RHS producing the value we should actually
5081 store into the LHS. */
5083 my_friendly_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE),
5085 lhs = stabilize_reference (lhs);
5086 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
5087 if (newrhs == error_mark_node)
5089 error (" in evaluation of `%Q(%#T, %#T)'", modifycode,
5090 TREE_TYPE (lhs), TREE_TYPE (rhs));
5091 return error_mark_node;
5094 /* Now it looks like a plain assignment. */
5095 modifycode = NOP_EXPR;
5097 my_friendly_assert (TREE_CODE (lhstype) != REFERENCE_TYPE, 20011220);
5098 my_friendly_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE,
5102 /* The left-hand side must be an lvalue. */
5103 if (!lvalue_or_else (lhs, "assignment"))
5104 return error_mark_node;
5106 /* Warn about modifying something that is `const'. Don't warn if
5107 this is initialization. */
5108 if (modifycode != INIT_EXPR
5109 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5110 /* Functions are not modifiable, even though they are
5112 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5113 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5114 /* If it's an aggregate and any field is const, then it is
5115 effectively const. */
5116 || (CLASS_TYPE_P (lhstype)
5117 && C_TYPE_FIELDS_READONLY (lhstype))))
5118 readonly_error (lhs, "assignment", 0);
5120 /* If storing into a structure or union member, it has probably been
5121 given type `int'. Compute the type that would go with the actual
5122 amount of storage the member occupies. */
5124 if (TREE_CODE (lhs) == COMPONENT_REF
5125 && (TREE_CODE (lhstype) == INTEGER_TYPE
5126 || TREE_CODE (lhstype) == REAL_TYPE
5127 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5129 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5131 /* If storing in a field that is in actuality a short or narrower
5132 than one, we must store in the field in its actual type. */
5134 if (lhstype != TREE_TYPE (lhs))
5136 /* Avoid warnings converting integral types back into enums for
5138 if (TREE_CODE (lhstype) == INTEGER_TYPE
5139 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5141 if (TREE_SIDE_EFFECTS (lhs))
5142 lhs = stabilize_reference (lhs);
5145 lhs = copy_node (lhs);
5146 TREE_TYPE (lhs) = lhstype;
5150 /* Convert new value to destination type. */
5152 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5156 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5157 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5159 error ("incompatible types in assignment of `%T' to `%T'",
5160 TREE_TYPE (rhs), lhstype);
5161 return error_mark_node;
5164 /* Allow array assignment in compiler-generated code. */
5165 if (! DECL_ARTIFICIAL (current_function_decl))
5166 pedwarn ("ISO C++ forbids assignment of arrays");
5168 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5169 ? 1 + (modifycode != INIT_EXPR): 0;
5170 return build_vec_init (lhs, NULL_TREE, newrhs, from_array);
5173 if (modifycode == INIT_EXPR)
5174 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5175 "initialization", NULL_TREE, 0);
5178 /* Avoid warnings on enum bit fields. */
5179 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5180 && TREE_CODE (lhstype) == INTEGER_TYPE)
5182 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5184 newrhs = convert_force (lhstype, newrhs, 0);
5187 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5189 if (TREE_CODE (newrhs) == CALL_EXPR
5190 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5191 newrhs = build_cplus_new (lhstype, newrhs);
5193 /* Can't initialize directly from a TARGET_EXPR, since that would
5194 cause the lhs to be constructed twice, and possibly result in
5195 accidental self-initialization. So we force the TARGET_EXPR to be
5196 expanded without a target. */
5197 if (TREE_CODE (newrhs) == TARGET_EXPR)
5198 newrhs = build (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5199 TREE_OPERAND (newrhs, 0));
5202 if (newrhs == error_mark_node)
5203 return error_mark_node;
5205 result = build (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5206 lhstype, lhs, newrhs);
5208 TREE_SIDE_EFFECTS (result) = 1;
5210 /* If we got the LHS in a different type for storing in,
5211 convert the result back to the nominal type of LHS
5212 so that the value we return always has the same type
5213 as the LHS argument. */
5215 if (olhstype == TREE_TYPE (result))
5219 result = build (COMPOUND_EXPR, olhstype, result, olhs);
5220 TREE_NO_WARNING (result) = 1;
5223 return convert_for_assignment (olhstype, result, "assignment",
5228 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5230 if (processing_template_decl)
5231 return build_min_nt (MODOP_EXPR, lhs,
5232 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5234 if (modifycode != NOP_EXPR)
5236 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5237 make_node (modifycode),
5238 /*overloaded_p=*/NULL);
5242 return build_modify_expr (lhs, modifycode, rhs);
5246 /* Get difference in deltas for different pointer to member function
5247 types. Returns an integer constant of type PTRDIFF_TYPE_NODE. If
5248 the conversion is invalid, the constant is zero. If FORCE is true,
5249 then allow reverse conversions as well.
5251 Note that the naming of FROM and TO is kind of backwards; the return
5252 value is what we add to a TO in order to get a FROM. They are named
5253 this way because we call this function to find out how to convert from
5254 a pointer to member of FROM to a pointer to member of TO. */
5257 get_delta_difference (tree from, tree to, int force)
5264 /* Assume no conversion is required. */
5265 result = integer_zero_node;
5266 binfo = lookup_base (to, from, ba_check, &kind);
5267 if (kind == bk_inaccessible || kind == bk_ambig)
5268 error (" in pointer to member function conversion");
5273 error_not_base_type (from, to);
5274 error (" in pointer to member conversion");
5278 binfo = lookup_base (from, to, ba_check, &kind);
5281 virt_binfo = binfo_from_vbase (binfo);
5283 /* This is a reinterpret cast, we choose to do nothing. */
5284 warning ("pointer to member cast via virtual base `%T'",
5285 BINFO_TYPE (virt_binfo));
5287 result = size_diffop (size_zero_node, BINFO_OFFSET (binfo));
5293 virt_binfo = binfo_from_vbase (binfo);
5295 result = BINFO_OFFSET (binfo);
5298 /* This is a reinterpret cast, we choose to do nothing. */
5300 warning ("pointer to member cast via virtual base `%T'",
5301 BINFO_TYPE (virt_binfo));
5303 error ("pointer to member conversion via virtual base `%T'",
5304 BINFO_TYPE (virt_binfo));
5308 return fold (convert_to_integer (ptrdiff_type_node, result));
5311 /* Return a constructor for the pointer-to-member-function TYPE using
5312 the other components as specified. */
5315 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5321 /* Pull the FIELD_DECLs out of the type. */
5322 pfn_field = TYPE_FIELDS (type);
5323 delta_field = TREE_CHAIN (pfn_field);
5325 /* Make sure DELTA has the type we want. */
5326 delta = convert_and_check (delta_type_node, delta);
5328 /* Finish creating the initializer. */
5329 u = tree_cons (pfn_field, pfn,
5330 build_tree_list (delta_field, delta));
5331 u = build_constructor (type, u);
5332 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) & TREE_CONSTANT (delta);
5333 TREE_INVARIANT (u) = TREE_INVARIANT (pfn) & TREE_INVARIANT (delta);
5334 TREE_STATIC (u) = (TREE_CONSTANT (u)
5335 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5337 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5342 /* Build a constructor for a pointer to member function. It can be
5343 used to initialize global variables, local variable, or used
5344 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5347 If FORCE is nonzero, then force this conversion, even if
5348 we would rather not do it. Usually set when using an explicit
5351 Return error_mark_node, if something goes wrong. */
5354 build_ptrmemfunc (tree type, tree pfn, int force)
5360 if (error_operand_p (pfn))
5361 return error_mark_node;
5363 pfn_type = TREE_TYPE (pfn);
5364 to_type = build_ptrmemfunc_type (type);
5366 /* Handle multiple conversions of pointer to member functions. */
5367 if (TYPE_PTRMEMFUNC_P (pfn_type))
5369 tree delta = NULL_TREE;
5370 tree npfn = NULL_TREE;
5374 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn))
5375 error ("invalid conversion to type `%T' from type `%T'",
5378 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5379 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5382 /* We don't have to do any conversion to convert a
5383 pointer-to-member to its own type. But, we don't want to
5384 just return a PTRMEM_CST if there's an explicit cast; that
5385 cast should make the expression an invalid template argument. */
5386 if (TREE_CODE (pfn) != PTRMEM_CST)
5388 if (same_type_p (to_type, pfn_type))
5390 else if (integer_zerop (n))
5391 return build_reinterpret_cast (to_type, pfn);
5394 if (TREE_SIDE_EFFECTS (pfn))
5395 pfn = save_expr (pfn);
5397 /* Obtain the function pointer and the current DELTA. */
5398 if (TREE_CODE (pfn) == PTRMEM_CST)
5399 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
5402 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
5403 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
5406 /* Just adjust the DELTA field. */
5407 my_friendly_assert (TREE_TYPE (delta) == ptrdiff_type_node, 20030727);
5408 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
5409 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
5410 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
5411 return build_ptrmemfunc1 (to_type, delta, npfn);
5414 /* Handle null pointer to member function conversions. */
5415 if (integer_zerop (pfn))
5417 pfn = build_c_cast (type, integer_zero_node);
5418 return build_ptrmemfunc1 (to_type,
5423 if (type_unknown_p (pfn))
5424 return instantiate_type (type, pfn, tf_error | tf_warning);
5426 fn = TREE_OPERAND (pfn, 0);
5427 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
5428 return make_ptrmem_cst (to_type, fn);
5431 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
5434 ??? There is no consistency as to the types returned for the above
5435 values. Some code acts as if it were a sizetype and some as if it were
5436 integer_type_node. */
5439 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
5441 tree type = TREE_TYPE (cst);
5442 tree fn = PTRMEM_CST_MEMBER (cst);
5443 tree ptr_class, fn_class;
5445 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
5447 /* The class that the function belongs to. */
5448 fn_class = DECL_CONTEXT (fn);
5450 /* The class that we're creating a pointer to member of. */
5451 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
5453 /* First, calculate the adjustment to the function's class. */
5454 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0);
5456 if (!DECL_VIRTUAL_P (fn))
5457 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
5460 /* If we're dealing with a virtual function, we have to adjust 'this'
5461 again, to point to the base which provides the vtable entry for
5462 fn; the call will do the opposite adjustment. */
5463 tree orig_class = DECL_CONTEXT (fn);
5464 tree binfo = binfo_or_else (orig_class, fn_class);
5465 *delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
5466 *delta, BINFO_OFFSET (binfo)));
5468 /* We set PFN to the vtable offset at which the function can be
5469 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
5470 case delta is shifted left, and then incremented). */
5471 *pfn = DECL_VINDEX (fn);
5472 *pfn = fold (build (MULT_EXPR, integer_type_node, *pfn,
5473 TYPE_SIZE_UNIT (vtable_entry_type)));
5475 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
5477 case ptrmemfunc_vbit_in_pfn:
5478 *pfn = fold (build (PLUS_EXPR, integer_type_node, *pfn,
5482 case ptrmemfunc_vbit_in_delta:
5483 *delta = fold (build (LSHIFT_EXPR, TREE_TYPE (*delta),
5484 *delta, integer_one_node));
5485 *delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
5486 *delta, integer_one_node));
5493 *pfn = fold (build1 (NOP_EXPR, TYPE_PTRMEMFUNC_FN_TYPE (type),
5498 /* Return an expression for PFN from the pointer-to-member function
5502 pfn_from_ptrmemfunc (tree t)
5504 if (TREE_CODE (t) == PTRMEM_CST)
5509 expand_ptrmemfunc_cst (t, &delta, &pfn);
5514 return build_ptrmemfunc_access_expr (t, pfn_identifier);
5517 /* Expression EXPR is about to be implicitly converted to TYPE. Warn
5518 if this is a potentially dangerous thing to do. Returns a possibly
5522 dubious_conversion_warnings (tree type, tree expr,
5523 const char *errtype, tree fndecl, int parmnum)
5525 type = non_reference (type);
5527 /* Issue warnings about peculiar, but valid, uses of NULL. */
5528 if (ARITHMETIC_TYPE_P (type) && expr == null_node)
5531 warning ("passing NULL used for non-pointer %s %P of `%D'",
5532 errtype, parmnum, fndecl);
5534 warning ("%s to non-pointer type `%T' from NULL", errtype, type);
5537 /* Warn about assigning a floating-point type to an integer type. */
5538 if (TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE
5539 && TREE_CODE (type) == INTEGER_TYPE)
5542 warning ("passing `%T' for %s %P of `%D'",
5543 TREE_TYPE (expr), errtype, parmnum, fndecl);
5545 warning ("%s to `%T' from `%T'", errtype, type, TREE_TYPE (expr));
5547 /* And warn about assigning a negative value to an unsigned
5549 else if (TYPE_UNSIGNED (type) && TREE_CODE (type) != BOOLEAN_TYPE)
5551 if (TREE_CODE (expr) == INTEGER_CST && TREE_NEGATED_INT (expr))
5554 warning ("passing negative value `%E' for %s %P of `%D'",
5555 expr, errtype, parmnum, fndecl);
5557 warning ("%s of negative value `%E' to `%T'",
5558 errtype, expr, type);
5561 overflow_warning (expr);
5563 if (TREE_CONSTANT (expr))
5569 /* Convert value RHS to type TYPE as preparation for an assignment to
5570 an lvalue of type TYPE. ERRTYPE is a string to use in error
5571 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
5572 are doing the conversion in order to pass the PARMNUMth argument of
5576 convert_for_assignment (tree type, tree rhs,
5577 const char *errtype, tree fndecl, int parmnum)
5580 enum tree_code coder;
5582 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
5583 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
5584 rhs = TREE_OPERAND (rhs, 0);
5586 rhstype = TREE_TYPE (rhs);
5587 coder = TREE_CODE (rhstype);
5589 if (TREE_CODE (type) == VECTOR_TYPE && coder == VECTOR_TYPE
5590 && vector_types_convertible_p (type, rhstype))
5591 return convert (type, rhs);
5593 if (rhs == error_mark_node || rhstype == error_mark_node)
5594 return error_mark_node;
5595 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
5596 return error_mark_node;
5598 /* The RHS of an assignment cannot have void type. */
5599 if (coder == VOID_TYPE)
5601 error ("void value not ignored as it ought to be");
5602 return error_mark_node;
5605 /* Simplify the RHS if possible. */
5606 if (TREE_CODE (rhs) == CONST_DECL)
5607 rhs = DECL_INITIAL (rhs);
5609 /* We do not use decl_constant_value here because of this case:
5611 const char* const s = "s";
5613 The conversion rules for a string literal are more lax than for a
5614 variable; in particular, a string literal can be converted to a
5615 "char *" but the variable "s" cannot be converted in the same
5616 way. If the conversion is allowed, the optimization should be
5617 performed while creating the converted expression. */
5621 The expression is implicitly converted (clause _conv_) to the
5622 cv-unqualified type of the left operand.
5624 We allow bad conversions here because by the time we get to this point
5625 we are committed to doing the conversion. If we end up doing a bad
5626 conversion, convert_like will complain. */
5627 if (!can_convert_arg_bad (type, rhstype, rhs))
5629 /* When -Wno-pmf-conversions is use, we just silently allow
5630 conversions from pointers-to-members to plain pointers. If
5631 the conversion doesn't work, cp_convert will complain. */
5633 && TYPE_PTR_P (type)
5634 && TYPE_PTRMEMFUNC_P (rhstype))
5635 rhs = cp_convert (strip_top_quals (type), rhs);
5638 /* If the right-hand side has unknown type, then it is an
5639 overloaded function. Call instantiate_type to get error
5641 if (rhstype == unknown_type_node)
5642 instantiate_type (type, rhs, tf_error | tf_warning);
5644 error ("cannot convert `%T' to `%T' for argument `%P' to `%D'",
5645 rhstype, type, parmnum, fndecl);
5647 error ("cannot convert `%T' to `%T' in %s", rhstype, type,
5649 return error_mark_node;
5652 return perform_implicit_conversion (strip_top_quals (type), rhs);
5655 /* Convert RHS to be of type TYPE.
5656 If EXP is nonzero, it is the target of the initialization.
5657 ERRTYPE is a string to use in error messages.
5659 Two major differences between the behavior of
5660 `convert_for_assignment' and `convert_for_initialization'
5661 are that references are bashed in the former, while
5662 copied in the latter, and aggregates are assigned in
5663 the former (operator=) while initialized in the
5666 If using constructor make sure no conversion operator exists, if one does
5667 exist, an ambiguity exists.
5669 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
5672 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
5673 const char *errtype, tree fndecl, int parmnum)
5675 enum tree_code codel = TREE_CODE (type);
5677 enum tree_code coder;
5679 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5680 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
5681 if (TREE_CODE (rhs) == NOP_EXPR
5682 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
5683 && codel != REFERENCE_TYPE)
5684 rhs = TREE_OPERAND (rhs, 0);
5686 if (rhs == error_mark_node
5687 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
5688 return error_mark_node;
5690 if (TREE_CODE (TREE_TYPE (rhs)) == REFERENCE_TYPE)
5691 rhs = convert_from_reference (rhs);
5693 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
5694 && TREE_CODE (type) != ARRAY_TYPE
5695 && (TREE_CODE (type) != REFERENCE_TYPE
5696 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
5697 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
5698 && (TREE_CODE (type) != REFERENCE_TYPE
5699 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
5700 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
5701 rhs = decay_conversion (rhs);
5703 rhstype = TREE_TYPE (rhs);
5704 coder = TREE_CODE (rhstype);
5706 if (coder == ERROR_MARK)
5707 return error_mark_node;
5709 /* We accept references to incomplete types, so we can
5710 return here before checking if RHS is of complete type. */
5712 if (codel == REFERENCE_TYPE)
5714 /* This should eventually happen in convert_arguments. */
5715 int savew = 0, savee = 0;
5718 savew = warningcount, savee = errorcount;
5719 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE,
5723 if (warningcount > savew)
5724 cp_warning_at ("in passing argument %P of `%+D'", parmnum, fndecl);
5725 else if (errorcount > savee)
5726 cp_error_at ("in passing argument %P of `%+D'", parmnum, fndecl);
5732 exp = require_complete_type (exp);
5733 if (exp == error_mark_node)
5734 return error_mark_node;
5736 rhstype = non_reference (rhstype);
5738 type = complete_type (type);
5740 if (IS_AGGR_TYPE (type))
5741 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
5743 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
5746 /* Expand an ASM statement with operands, handling output operands
5747 that are not variables or INDIRECT_REFS by transforming such
5748 cases into cases that expand_asm_operands can handle.
5750 Arguments are same as for expand_asm_operands.
5752 We don't do default conversions on all inputs, because it can screw
5753 up operands that are expected to be in memory. */
5756 c_expand_asm_operands (tree string, tree outputs, tree inputs, tree clobbers,
5757 int vol, location_t locus)
5759 int noutputs = list_length (outputs);
5761 /* o[I] is the place that output number I should be written. */
5762 tree *o = alloca (noutputs * sizeof (tree));
5765 /* Record the contents of OUTPUTS before it is modified. */
5766 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
5767 o[i] = TREE_VALUE (tail);
5769 /* Generate the ASM_OPERANDS insn;
5770 store into the TREE_VALUEs of OUTPUTS some trees for
5771 where the values were actually stored. */
5772 expand_asm_operands (string, outputs, inputs, clobbers, vol, locus);
5774 /* Copy all the intermediate outputs into the specified outputs. */
5775 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
5777 if (o[i] != TREE_VALUE (tail))
5779 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
5780 const0_rtx, VOIDmode, EXPAND_NORMAL);
5783 /* Restore the original value so that it's correct the next
5784 time we expand this function. */
5785 TREE_VALUE (tail) = o[i];
5787 /* Detect modification of read-only values.
5788 (Otherwise done by build_modify_expr.) */
5791 tree type = TREE_TYPE (o[i]);
5792 if (type != error_mark_node
5793 && (CP_TYPE_CONST_P (type)
5794 || (CLASS_TYPE_P (type) && C_TYPE_FIELDS_READONLY (type))))
5795 readonly_error (o[i], "modification by `asm'", 1);
5799 /* Those MODIFY_EXPRs could do autoincrements. */
5803 /* If RETVAL is the address of, or a reference to, a local variable or
5804 temporary give an appropriate warning. */
5807 maybe_warn_about_returning_address_of_local (tree retval)
5809 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
5810 tree whats_returned = retval;
5814 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
5815 whats_returned = TREE_OPERAND (whats_returned, 1);
5816 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
5817 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
5818 || TREE_CODE (whats_returned) == NOP_EXPR)
5819 whats_returned = TREE_OPERAND (whats_returned, 0);
5824 if (TREE_CODE (whats_returned) != ADDR_EXPR)
5826 whats_returned = TREE_OPERAND (whats_returned, 0);
5828 if (TREE_CODE (valtype) == REFERENCE_TYPE)
5830 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
5831 || TREE_CODE (whats_returned) == TARGET_EXPR)
5833 warning ("returning reference to temporary");
5836 if (TREE_CODE (whats_returned) == VAR_DECL
5837 && DECL_NAME (whats_returned)
5838 && TEMP_NAME_P (DECL_NAME (whats_returned)))
5840 warning ("reference to non-lvalue returned");
5845 if (DECL_P (whats_returned)
5846 && DECL_NAME (whats_returned)
5847 && DECL_FUNCTION_SCOPE_P (whats_returned)
5848 && !(TREE_STATIC (whats_returned)
5849 || TREE_PUBLIC (whats_returned)))
5851 if (TREE_CODE (valtype) == REFERENCE_TYPE)
5852 cp_warning_at ("reference to local variable `%D' returned",
5855 cp_warning_at ("address of local variable `%D' returned",
5861 /* Check that returning RETVAL from the current function is valid.
5862 Return an expression explicitly showing all conversions required to
5863 change RETVAL into the function return type, and to assign it to
5864 the DECL_RESULT for the function. */
5867 check_return_expr (tree retval)
5870 /* The type actually returned by the function, after any
5873 int fn_returns_value_p;
5875 /* A `volatile' function is one that isn't supposed to return, ever.
5876 (This is a G++ extension, used to get better code for functions
5877 that call the `volatile' function.) */
5878 if (TREE_THIS_VOLATILE (current_function_decl))
5879 warning ("function declared `noreturn' has a `return' statement");
5881 /* Check for various simple errors. */
5882 if (DECL_DESTRUCTOR_P (current_function_decl))
5885 error ("returning a value from a destructor");
5888 else if (DECL_CONSTRUCTOR_P (current_function_decl))
5890 if (in_function_try_handler)
5891 /* If a return statement appears in a handler of the
5892 function-try-block of a constructor, the program is ill-formed. */
5893 error ("cannot return from a handler of a function-try-block of a constructor");
5895 /* You can't return a value from a constructor. */
5896 error ("returning a value from a constructor");
5900 if (processing_template_decl)
5902 current_function_returns_value = 1;
5906 /* When no explicit return-value is given in a function with a named
5907 return value, the named return value is used. */
5908 result = DECL_RESULT (current_function_decl);
5909 valtype = TREE_TYPE (result);
5910 my_friendly_assert (valtype != NULL_TREE, 19990924);
5911 fn_returns_value_p = !VOID_TYPE_P (valtype);
5912 if (!retval && DECL_NAME (result) && fn_returns_value_p)
5915 /* Check for a return statement with no return value in a function
5916 that's supposed to return a value. */
5917 if (!retval && fn_returns_value_p)
5919 pedwarn ("return-statement with no value, in function returning '%T'",
5921 /* Clear this, so finish_function won't say that we reach the
5922 end of a non-void function (which we don't, we gave a
5924 current_function_returns_null = 0;
5926 /* Check for a return statement with a value in a function that
5927 isn't supposed to return a value. */
5928 else if (retval && !fn_returns_value_p)
5930 if (VOID_TYPE_P (TREE_TYPE (retval)))
5931 /* You can return a `void' value from a function of `void'
5932 type. In that case, we have to evaluate the expression for
5933 its side-effects. */
5934 finish_expr_stmt (retval);
5936 pedwarn ("return-statement with a value, in function "
5937 "returning 'void'");
5939 current_function_returns_null = 1;
5941 /* There's really no value to return, after all. */
5945 /* Remember that this function can sometimes return without a
5947 current_function_returns_null = 1;
5949 /* Remember that this function did return a value. */
5950 current_function_returns_value = 1;
5952 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
5953 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
5954 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
5955 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
5957 && null_ptr_cst_p (retval))
5958 warning ("`operator new' must not return NULL unless it is declared `throw()' (or -fcheck-new is in effect)");
5960 /* Effective C++ rule 15. See also start_function. */
5962 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR)
5963 && retval != current_class_ref)
5964 warning ("`operator=' should return a reference to `*this'");
5966 /* The fabled Named Return Value optimization, as per [class.copy]/15:
5968 [...] For a function with a class return type, if the expression
5969 in the return statement is the name of a local object, and the cv-
5970 unqualified type of the local object is the same as the function
5971 return type, an implementation is permitted to omit creating the tem-
5972 porary object to hold the function return value [...]
5974 So, if this is a value-returning function that always returns the same
5975 local variable, remember it.
5977 It might be nice to be more flexible, and choose the first suitable
5978 variable even if the function sometimes returns something else, but
5979 then we run the risk of clobbering the variable we chose if the other
5980 returned expression uses the chosen variable somehow. And people expect
5981 this restriction, anyway. (jason 2000-11-19)
5983 See finish_function and finalize_nrv for the rest of this optimization. */
5985 if (fn_returns_value_p && flag_elide_constructors)
5987 if (retval != NULL_TREE
5988 && (current_function_return_value == NULL_TREE
5989 || current_function_return_value == retval)
5990 && TREE_CODE (retval) == VAR_DECL
5991 && DECL_CONTEXT (retval) == current_function_decl
5992 && ! TREE_STATIC (retval)
5993 && (DECL_ALIGN (retval)
5994 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
5995 && same_type_p ((TYPE_MAIN_VARIANT
5996 (TREE_TYPE (retval))),
5998 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
5999 current_function_return_value = retval;
6001 current_function_return_value = error_mark_node;
6004 /* We don't need to do any conversions when there's nothing being
6006 if (!retval || retval == error_mark_node)
6009 /* Do any required conversions. */
6010 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
6011 /* No conversions are required. */
6015 /* The type the function is declared to return. */
6016 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
6018 /* First convert the value to the function's return type, then
6019 to the type of return value's location to handle the
6020 case that functype is smaller than the valtype. */
6021 retval = convert_for_initialization
6022 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
6023 "return", NULL_TREE, 0);
6024 retval = convert (valtype, retval);
6026 /* If the conversion failed, treat this just like `return;'. */
6027 if (retval == error_mark_node)
6029 /* We can't initialize a register from a AGGR_INIT_EXPR. */
6030 else if (! current_function_returns_struct
6031 && TREE_CODE (retval) == TARGET_EXPR
6032 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
6033 retval = build (COMPOUND_EXPR, TREE_TYPE (retval), retval,
6034 TREE_OPERAND (retval, 0));
6036 maybe_warn_about_returning_address_of_local (retval);
6039 /* Actually copy the value returned into the appropriate location. */
6040 if (retval && retval != result)
6041 retval = build (INIT_EXPR, TREE_TYPE (result), result, retval);
6047 /* Returns nonzero if the pointer-type FROM can be converted to the
6048 pointer-type TO via a qualification conversion. If CONSTP is -1,
6049 then we return nonzero if the pointers are similar, and the
6050 cv-qualification signature of FROM is a proper subset of that of TO.
6052 If CONSTP is positive, then all outer pointers have been
6056 comp_ptr_ttypes_real (tree to, tree from, int constp)
6058 bool to_more_cv_qualified = false;
6060 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6062 if (TREE_CODE (to) != TREE_CODE (from))
6065 if (TREE_CODE (from) == OFFSET_TYPE
6066 && !same_type_p (TYPE_OFFSET_BASETYPE (from),
6067 TYPE_OFFSET_BASETYPE (to)))
6070 /* Const and volatile mean something different for function types,
6071 so the usual checks are not appropriate. */
6072 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6074 if (!at_least_as_qualified_p (to, from))
6077 if (!at_least_as_qualified_p (from, to))
6081 to_more_cv_qualified = true;
6085 constp &= TYPE_READONLY (to);
6088 if (TREE_CODE (to) != POINTER_TYPE && !TYPE_PTRMEM_P (to))
6089 return ((constp >= 0 || to_more_cv_qualified)
6090 && same_type_ignoring_top_level_qualifiers_p (to, from));
6094 /* When comparing, say, char ** to char const **, this function takes
6095 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6096 types to this function. */
6099 comp_ptr_ttypes (tree to, tree from)
6101 return comp_ptr_ttypes_real (to, from, 1);
6104 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6105 type or inheritance-related types, regardless of cv-quals. */
6108 ptr_reasonably_similar (tree to, tree from)
6110 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6112 /* Any target type is similar enough to void. */
6113 if (TREE_CODE (to) == VOID_TYPE
6114 || TREE_CODE (from) == VOID_TYPE)
6117 if (TREE_CODE (to) != TREE_CODE (from))
6120 if (TREE_CODE (from) == OFFSET_TYPE
6121 && comptypes (TYPE_OFFSET_BASETYPE (to),
6122 TYPE_OFFSET_BASETYPE (from),
6123 COMPARE_BASE | COMPARE_DERIVED))
6126 if (TREE_CODE (to) == INTEGER_TYPE
6127 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6130 if (TREE_CODE (to) == FUNCTION_TYPE)
6133 if (TREE_CODE (to) != POINTER_TYPE)
6135 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6136 COMPARE_BASE | COMPARE_DERIVED);
6140 /* Like comp_ptr_ttypes, for const_cast. */
6143 comp_ptr_ttypes_const (tree to, tree from)
6145 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6147 if (TREE_CODE (to) != TREE_CODE (from))
6150 if (TREE_CODE (from) == OFFSET_TYPE
6151 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6152 TYPE_OFFSET_BASETYPE (to)))
6155 if (TREE_CODE (to) != POINTER_TYPE)
6156 return same_type_ignoring_top_level_qualifiers_p (to, from);
6160 /* Returns the type qualifiers for this type, including the qualifiers on the
6161 elements for an array type. */
6164 cp_type_quals (tree type)
6166 type = strip_array_types (type);
6167 if (type == error_mark_node)
6168 return TYPE_UNQUALIFIED;
6169 return TYPE_QUALS (type);
6172 /* Returns nonzero if the TYPE contains a mutable member. */
6175 cp_has_mutable_p (tree type)
6177 type = strip_array_types (type);
6179 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6182 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6183 exemplar types such that casting T1 to T2 is casting away castness
6184 if and only if there is no implicit conversion from T1 to T2. */
6187 casts_away_constness_r (tree *t1, tree *t2)
6192 /* [expr.const.cast]
6194 For multi-level pointer to members and multi-level mixed pointers
6195 and pointers to members (conv.qual), the "member" aspect of a
6196 pointer to member level is ignored when determining if a const
6197 cv-qualifier has been cast away. */
6198 if (TYPE_PTRMEM_P (*t1))
6199 *t1 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t1));
6200 if (TYPE_PTRMEM_P (*t2))
6201 *t2 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t2));
6203 /* [expr.const.cast]
6205 For two pointer types:
6207 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6208 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6211 casting from X1 to X2 casts away constness if, for a non-pointer
6212 type T there does not exist an implicit conversion (clause
6215 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6219 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6221 if (TREE_CODE (*t1) != POINTER_TYPE
6222 || TREE_CODE (*t2) != POINTER_TYPE)
6224 *t1 = cp_build_qualified_type (void_type_node,
6225 cp_type_quals (*t1));
6226 *t2 = cp_build_qualified_type (void_type_node,
6227 cp_type_quals (*t2));
6231 quals1 = cp_type_quals (*t1);
6232 quals2 = cp_type_quals (*t2);
6233 *t1 = TREE_TYPE (*t1);
6234 *t2 = TREE_TYPE (*t2);
6235 casts_away_constness_r (t1, t2);
6236 *t1 = build_pointer_type (*t1);
6237 *t2 = build_pointer_type (*t2);
6238 *t1 = cp_build_qualified_type (*t1, quals1);
6239 *t2 = cp_build_qualified_type (*t2, quals2);
6242 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6246 casts_away_constness (tree t1, tree t2)
6248 if (TREE_CODE (t2) == REFERENCE_TYPE)
6250 /* [expr.const.cast]
6252 Casting from an lvalue of type T1 to an lvalue of type T2
6253 using a reference cast casts away constness if a cast from an
6254 rvalue of type "pointer to T1" to the type "pointer to T2"
6255 casts away constness. */
6256 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6257 return casts_away_constness (build_pointer_type (t1),
6258 build_pointer_type (TREE_TYPE (t2)));
6261 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6262 /* [expr.const.cast]
6264 Casting from an rvalue of type "pointer to data member of X
6265 of type T1" to the type "pointer to data member of Y of type
6266 T2" casts away constness if a cast from an rvalue of type
6267 "pointer to T1" to the type "pointer to T2" casts away
6269 return casts_away_constness
6270 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6271 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6273 /* Casting away constness is only something that makes sense for
6274 pointer or reference types. */
6275 if (TREE_CODE (t1) != POINTER_TYPE
6276 || TREE_CODE (t2) != POINTER_TYPE)
6279 /* Top-level qualifiers don't matter. */
6280 t1 = TYPE_MAIN_VARIANT (t1);
6281 t2 = TYPE_MAIN_VARIANT (t2);
6282 casts_away_constness_r (&t1, &t2);
6283 if (!can_convert (t2, t1))
6289 /* If T is a REFERENCE_TYPE return the type to which T refers.
6290 Otherwise, return T itself. */
6293 non_reference (tree t)
6295 if (TREE_CODE (t) == REFERENCE_TYPE)