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 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"
48 static tree convert_for_assignment (tree, tree, const char *, tree, int);
49 static tree cp_pointer_int_sum (enum tree_code, tree, tree);
50 static tree rationalize_conditional_expr (enum tree_code, tree);
51 static int comp_ptr_ttypes_real (tree, tree, int);
52 static int comp_ptr_ttypes_const (tree, tree);
53 static bool comp_except_types (tree, tree, bool);
54 static bool comp_array_types (tree, tree, bool);
55 static tree common_base_type (tree, tree);
56 static tree lookup_anon_field (tree, tree);
57 static tree pointer_diff (tree, tree, tree);
58 static tree get_delta_difference (tree, tree, int);
59 static void casts_away_constness_r (tree *, tree *);
60 static bool casts_away_constness (tree, tree);
61 static void maybe_warn_about_returning_address_of_local (tree);
62 static tree lookup_destructor (tree, tree, tree);
64 /* Return the target type of TYPE, which means return T for:
65 T*, T&, T[], T (...), and otherwise, just T. */
68 target_type (tree type)
70 type = non_reference (type);
71 while (TREE_CODE (type) == POINTER_TYPE
72 || TREE_CODE (type) == ARRAY_TYPE
73 || TREE_CODE (type) == FUNCTION_TYPE
74 || TREE_CODE (type) == METHOD_TYPE
75 || TYPE_PTRMEM_P (type))
76 type = TREE_TYPE (type);
80 /* Do `exp = require_complete_type (exp);' to make sure exp
81 does not have an incomplete type. (That includes void types.)
82 Returns the error_mark_node if the VALUE does not have
83 complete type when this function returns. */
86 require_complete_type (tree value)
90 if (processing_template_decl || value == error_mark_node)
93 if (TREE_CODE (value) == OVERLOAD)
94 type = unknown_type_node;
96 type = TREE_TYPE (value);
98 /* First, detect a valid value with a complete type. */
99 if (COMPLETE_TYPE_P (type))
102 if (complete_type_or_else (type, value))
105 return error_mark_node;
108 /* Try to complete TYPE, if it is incomplete. For example, if TYPE is
109 a template instantiation, do the instantiation. Returns TYPE,
110 whether or not it could be completed, unless something goes
111 horribly wrong, in which case the error_mark_node is returned. */
114 complete_type (tree type)
116 if (type == NULL_TREE)
117 /* Rather than crash, we return something sure to cause an error
119 return error_mark_node;
121 if (type == error_mark_node || COMPLETE_TYPE_P (type))
123 else if (TREE_CODE (type) == ARRAY_TYPE && TYPE_DOMAIN (type))
125 tree t = complete_type (TREE_TYPE (type));
126 if (COMPLETE_TYPE_P (t) && ! processing_template_decl)
128 TYPE_NEEDS_CONSTRUCTING (type)
129 = TYPE_NEEDS_CONSTRUCTING (TYPE_MAIN_VARIANT (t));
130 TYPE_HAS_NONTRIVIAL_DESTRUCTOR (type)
131 = TYPE_HAS_NONTRIVIAL_DESTRUCTOR (TYPE_MAIN_VARIANT (t));
133 else if (CLASS_TYPE_P (type) && CLASSTYPE_TEMPLATE_INSTANTIATION (type))
134 instantiate_class_template (TYPE_MAIN_VARIANT (type));
139 /* Like complete_type, but issue an error if the TYPE cannot be completed.
140 VALUE is used for informative diagnostics. DIAG_TYPE indicates the type
141 of diagnostic: 0 for an error, 1 for a warning, 2 for a pedwarn.
142 Returns NULL_TREE if the type cannot be made complete. */
145 complete_type_or_diagnostic (tree type, tree value, int diag_type)
147 type = complete_type (type);
148 if (type == error_mark_node)
149 /* We already issued an error. */
151 else if (!COMPLETE_TYPE_P (type))
153 cxx_incomplete_type_diagnostic (value, type, diag_type);
160 /* Return truthvalue of whether type of EXP is instantiated. */
163 type_unknown_p (tree exp)
165 return (TREE_CODE (exp) == OVERLOAD
166 || TREE_CODE (exp) == TREE_LIST
167 || TREE_TYPE (exp) == unknown_type_node);
171 /* Return the common type of two parameter lists.
172 We assume that comptypes has already been done and returned 1;
173 if that isn't so, this may crash.
175 As an optimization, free the space we allocate if the parameter
176 lists are already common. */
179 commonparms (tree p1, tree p2)
181 tree oldargs = p1, newargs, n;
185 len = list_length (p1);
186 newargs = tree_last (p1);
188 if (newargs == void_list_node)
197 newargs = tree_cons (NULL_TREE, NULL_TREE, newargs);
202 p1 = TREE_CHAIN (p1), p2 = TREE_CHAIN (p2), n = TREE_CHAIN (n), i++)
204 if (TREE_PURPOSE (p1) && !TREE_PURPOSE (p2))
206 TREE_PURPOSE (n) = TREE_PURPOSE (p1);
209 else if (! TREE_PURPOSE (p1))
211 if (TREE_PURPOSE (p2))
213 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
219 if (1 != simple_cst_equal (TREE_PURPOSE (p1), TREE_PURPOSE (p2)))
221 TREE_PURPOSE (n) = TREE_PURPOSE (p2);
223 if (TREE_VALUE (p1) != TREE_VALUE (p2))
226 TREE_VALUE (n) = merge_types (TREE_VALUE (p1), TREE_VALUE (p2));
229 TREE_VALUE (n) = TREE_VALUE (p1);
237 /* Given a type, perhaps copied for a typedef,
238 find the "original" version of it. */
240 original_type (tree t)
242 while (TYPE_NAME (t) != NULL_TREE)
244 tree x = TYPE_NAME (t);
245 if (TREE_CODE (x) != TYPE_DECL)
247 x = DECL_ORIGINAL_TYPE (x);
255 /* T1 and T2 are arithmetic or enumeration types. Return the type
256 that will result from the "usual arithmetic conversions" on T1 and
257 T2 as described in [expr]. */
260 type_after_usual_arithmetic_conversions (tree t1, tree t2)
262 enum tree_code code1 = TREE_CODE (t1);
263 enum tree_code code2 = TREE_CODE (t2);
266 /* FIXME: Attributes. */
267 my_friendly_assert (ARITHMETIC_TYPE_P (t1)
268 || TREE_CODE (t1) == COMPLEX_TYPE
269 || TREE_CODE (t1) == ENUMERAL_TYPE,
271 my_friendly_assert (ARITHMETIC_TYPE_P (t2)
272 || TREE_CODE (t2) == COMPLEX_TYPE
273 || TREE_CODE (t2) == ENUMERAL_TYPE,
276 /* In what follows, we slightly generalize the rules given in [expr] so
277 as to deal with `long long' and `complex'. First, merge the
279 attributes = (*targetm.merge_type_attributes) (t1, t2);
281 /* If one type is complex, form the common type of the non-complex
282 components, then make that complex. Use T1 or T2 if it is the
284 if (code1 == COMPLEX_TYPE || code2 == COMPLEX_TYPE)
286 tree subtype1 = code1 == COMPLEX_TYPE ? TREE_TYPE (t1) : t1;
287 tree subtype2 = code2 == COMPLEX_TYPE ? TREE_TYPE (t2) : t2;
289 = type_after_usual_arithmetic_conversions (subtype1, subtype2);
291 if (code1 == COMPLEX_TYPE && TREE_TYPE (t1) == subtype)
292 return build_type_attribute_variant (t1, attributes);
293 else if (code2 == COMPLEX_TYPE && TREE_TYPE (t2) == subtype)
294 return build_type_attribute_variant (t2, attributes);
296 return build_type_attribute_variant (build_complex_type (subtype),
300 /* If only one is real, use it as the result. */
301 if (code1 == REAL_TYPE && code2 != REAL_TYPE)
302 return build_type_attribute_variant (t1, attributes);
303 if (code2 == REAL_TYPE && code1 != REAL_TYPE)
304 return build_type_attribute_variant (t2, attributes);
306 /* Perform the integral promotions. */
307 if (code1 != REAL_TYPE)
309 t1 = type_promotes_to (t1);
310 t2 = type_promotes_to (t2);
313 /* Both real or both integers; use the one with greater precision. */
314 if (TYPE_PRECISION (t1) > TYPE_PRECISION (t2))
315 return build_type_attribute_variant (t1, attributes);
316 else if (TYPE_PRECISION (t2) > TYPE_PRECISION (t1))
317 return build_type_attribute_variant (t2, attributes);
319 /* The types are the same; no need to do anything fancy. */
320 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
321 return build_type_attribute_variant (t1, attributes);
323 if (code1 != REAL_TYPE)
325 /* If one is a sizetype, use it so size_binop doesn't blow up. */
326 if (TYPE_IS_SIZETYPE (t1) > TYPE_IS_SIZETYPE (t2))
327 return build_type_attribute_variant (t1, attributes);
328 if (TYPE_IS_SIZETYPE (t2) > TYPE_IS_SIZETYPE (t1))
329 return build_type_attribute_variant (t2, attributes);
331 /* If one is unsigned long long, then convert the other to unsigned
333 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_unsigned_type_node)
334 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_unsigned_type_node))
335 return build_type_attribute_variant (long_long_unsigned_type_node,
337 /* If one is a long long, and the other is an unsigned long, and
338 long long can represent all the values of an unsigned long, then
339 convert to a long long. Otherwise, convert to an unsigned long
340 long. Otherwise, if either operand is long long, convert the
343 Since we're here, we know the TYPE_PRECISION is the same;
344 therefore converting to long long cannot represent all the values
345 of an unsigned long, so we choose unsigned long long in that
347 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_long_integer_type_node)
348 || same_type_p (TYPE_MAIN_VARIANT (t2), long_long_integer_type_node))
350 tree t = ((TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
351 ? long_long_unsigned_type_node
352 : long_long_integer_type_node);
353 return build_type_attribute_variant (t, attributes);
356 /* Go through the same procedure, but for longs. */
357 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_unsigned_type_node)
358 || same_type_p (TYPE_MAIN_VARIANT (t2), long_unsigned_type_node))
359 return build_type_attribute_variant (long_unsigned_type_node,
361 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_integer_type_node)
362 || same_type_p (TYPE_MAIN_VARIANT (t2), long_integer_type_node))
364 tree t = ((TREE_UNSIGNED (t1) || TREE_UNSIGNED (t2))
365 ? long_unsigned_type_node : long_integer_type_node);
366 return build_type_attribute_variant (t, attributes);
368 /* Otherwise prefer the unsigned one. */
369 if (TREE_UNSIGNED (t1))
370 return build_type_attribute_variant (t1, attributes);
372 return build_type_attribute_variant (t2, attributes);
376 if (same_type_p (TYPE_MAIN_VARIANT (t1), long_double_type_node)
377 || same_type_p (TYPE_MAIN_VARIANT (t2), long_double_type_node))
378 return build_type_attribute_variant (long_double_type_node,
380 if (same_type_p (TYPE_MAIN_VARIANT (t1), double_type_node)
381 || same_type_p (TYPE_MAIN_VARIANT (t2), double_type_node))
382 return build_type_attribute_variant (double_type_node,
384 if (same_type_p (TYPE_MAIN_VARIANT (t1), float_type_node)
385 || same_type_p (TYPE_MAIN_VARIANT (t2), float_type_node))
386 return build_type_attribute_variant (float_type_node,
389 /* Two floating-point types whose TYPE_MAIN_VARIANTs are none of
390 the standard C++ floating-point types. Logic earlier in this
391 function has already eliminated the possibility that
392 TYPE_PRECISION (t2) != TYPE_PRECISION (t1), so there's no
393 compelling reason to choose one or the other. */
394 return build_type_attribute_variant (t1, attributes);
398 /* Subroutine of composite_pointer_type to implement the recursive
399 case. See that function for documentation fo the parameters. */
402 composite_pointer_type_r (tree t1, tree t2, const char* location)
409 /* Determine the types pointed to by T1 and T2. */
410 if (TREE_CODE (t1) == POINTER_TYPE)
412 pointee1 = TREE_TYPE (t1);
413 pointee2 = TREE_TYPE (t2);
417 pointee1 = TYPE_PTRMEM_POINTED_TO_TYPE (t1);
418 pointee2 = TYPE_PTRMEM_POINTED_TO_TYPE (t2);
423 Otherwise, the composite pointer type is a pointer type
424 similar (_conv.qual_) to the type of one of the operands,
425 with a cv-qualification signature (_conv.qual_) that is the
426 union of the cv-qualification signatures of the operand
428 if (same_type_ignoring_top_level_qualifiers_p (pointee1, pointee2))
429 result_type = pointee1;
430 else if ((TREE_CODE (pointee1) == POINTER_TYPE
431 && TREE_CODE (pointee2) == POINTER_TYPE)
432 || (TYPE_PTR_TO_MEMBER_P (pointee1)
433 && TYPE_PTR_TO_MEMBER_P (pointee2)))
434 result_type = composite_pointer_type_r (pointee1, pointee2, location);
437 pedwarn ("%s between distinct pointer types `%T' and `%T' "
440 result_type = void_type_node;
442 result_type = cp_build_qualified_type (result_type,
443 (cp_type_quals (pointee1)
444 | cp_type_quals (pointee2)));
445 result_type = build_pointer_type (result_type);
446 /* If the original types were pointers to members, so is the
448 if (TYPE_PTR_TO_MEMBER_P (t1))
450 if (!same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
451 TYPE_PTRMEM_CLASS_TYPE (t2)))
452 pedwarn ("%s between distinct pointer types `%T' and `%T' "
455 result_type = build_ptrmem_type (TYPE_PTRMEM_CLASS_TYPE (t1),
459 /* Merge the attributes. */
460 attributes = (*targetm.merge_type_attributes) (t1, t2);
461 return build_type_attribute_variant (result_type, attributes);
464 /* Return the composite pointer type (see [expr.rel]) for T1 and T2.
465 ARG1 and ARG2 are the values with those types. The LOCATION is a
466 string describing the current location, in case an error occurs.
468 This routine also implements the computation of a common type for
469 pointers-to-members as per [expr.eq]. */
472 composite_pointer_type (tree t1, tree t2, tree arg1, tree arg2,
473 const char* location)
480 If one operand is a null pointer constant, the composite pointer
481 type is the type of the other operand. */
482 if (null_ptr_cst_p (arg1))
484 if (null_ptr_cst_p (arg2))
491 If one of the operands has type "pointer to cv1 void*", then
492 the other has type "pointer to cv2T", and the composite pointer
493 type is "pointer to cv12 void", where cv12 is the union of cv1
496 If either type is a pointer to void, make sure it is T1. */
497 if (TREE_CODE (t2) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t2)))
505 /* Now, if T1 is a pointer to void, merge the qualifiers. */
506 if (TREE_CODE (t1) == POINTER_TYPE && VOID_TYPE_P (TREE_TYPE (t1)))
511 if (pedantic && TYPE_PTRFN_P (t2))
512 pedwarn ("ISO C++ forbids %s between pointer of type `void *' and pointer-to-function", location);
514 = cp_build_qualified_type (void_type_node,
515 (cp_type_quals (TREE_TYPE (t1))
516 | cp_type_quals (TREE_TYPE (t2))));
517 result_type = build_pointer_type (result_type);
518 /* Merge the attributes. */
519 attributes = (*targetm.merge_type_attributes) (t1, t2);
520 return build_type_attribute_variant (result_type, attributes);
523 /* [expr.eq] permits the application of a pointer conversion to
524 bring the pointers to a common type. */
525 if (TREE_CODE (t1) == POINTER_TYPE && TREE_CODE (t2) == POINTER_TYPE
526 && CLASS_TYPE_P (TREE_TYPE (t1))
527 && CLASS_TYPE_P (TREE_TYPE (t2))
528 && !same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (t1),
531 class1 = TREE_TYPE (t1);
532 class2 = TREE_TYPE (t2);
534 if (DERIVED_FROM_P (class1, class2))
535 t2 = (build_pointer_type
536 (cp_build_qualified_type (class1, TYPE_QUALS (class2))));
537 else if (DERIVED_FROM_P (class2, class1))
538 t1 = (build_pointer_type
539 (cp_build_qualified_type (class2, TYPE_QUALS (class1))));
542 error ("%s between distinct pointer types `%T' and `%T' "
543 "lacks a cast", location, t1, t2);
544 return error_mark_node;
547 /* [expr.eq] permits the application of a pointer-to-member
548 conversion to change the class type of one of the types. */
549 else if (TYPE_PTR_TO_MEMBER_P (t1)
550 && !same_type_p (TYPE_PTRMEM_CLASS_TYPE (t1),
551 TYPE_PTRMEM_CLASS_TYPE (t2)))
553 class1 = TYPE_PTRMEM_CLASS_TYPE (t1);
554 class2 = TYPE_PTRMEM_CLASS_TYPE (t2);
556 if (DERIVED_FROM_P (class1, class2))
557 t1 = build_ptrmem_type (class2, TYPE_PTRMEM_POINTED_TO_TYPE (t1));
558 else if (DERIVED_FROM_P (class2, class1))
559 t2 = build_ptrmem_type (class1, TYPE_PTRMEM_POINTED_TO_TYPE (t2));
562 error ("%s between distinct pointer-to-member types `%T' and `%T' "
563 "lacks a cast", location, t1, t2);
564 return error_mark_node;
568 return composite_pointer_type_r (t1, t2, location);
571 /* Return the merged type of two types.
572 We assume that comptypes has already been done and returned 1;
573 if that isn't so, this may crash.
575 This just combines attributes and default arguments; any other
576 differences would cause the two types to compare unalike. */
579 merge_types (tree t1, tree t2)
581 register enum tree_code code1;
582 register enum tree_code code2;
585 /* Save time if the two types are the same. */
588 if (original_type (t1) == original_type (t2))
591 /* If one type is nonsense, use the other. */
592 if (t1 == error_mark_node)
594 if (t2 == error_mark_node)
597 /* Merge the attributes. */
598 attributes = (*targetm.merge_type_attributes) (t1, t2);
600 if (TYPE_PTRMEMFUNC_P (t1))
601 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
602 if (TYPE_PTRMEMFUNC_P (t2))
603 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
605 code1 = TREE_CODE (t1);
606 code2 = TREE_CODE (t2);
612 /* For two pointers, do this recursively on the target type. */
614 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
615 int quals = cp_type_quals (t1);
617 if (code1 == POINTER_TYPE)
618 t1 = build_pointer_type (target);
620 t1 = build_reference_type (target);
621 t1 = build_type_attribute_variant (t1, attributes);
622 t1 = cp_build_qualified_type (t1, quals);
624 if (TREE_CODE (target) == METHOD_TYPE)
625 t1 = build_ptrmemfunc_type (t1);
632 tree base = TYPE_OFFSET_BASETYPE (t1);
633 tree target = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
634 t1 = build_offset_type (base, target);
640 tree elt = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
641 /* Save space: see if the result is identical to one of the args. */
642 if (elt == TREE_TYPE (t1) && TYPE_DOMAIN (t1))
643 return build_type_attribute_variant (t1, attributes);
644 if (elt == TREE_TYPE (t2) && TYPE_DOMAIN (t2))
645 return build_type_attribute_variant (t2, attributes);
646 /* Merge the element types, and have a size if either arg has one. */
647 t1 = build_cplus_array_type
648 (elt, TYPE_DOMAIN (TYPE_DOMAIN (t1) ? t1 : t2));
653 /* Function types: prefer the one that specified arg types.
654 If both do, merge the arg types. Also merge the return types. */
656 tree valtype = merge_types (TREE_TYPE (t1), TREE_TYPE (t2));
657 tree p1 = TYPE_ARG_TYPES (t1);
658 tree p2 = TYPE_ARG_TYPES (t2);
661 /* Save space: see if the result is identical to one of the args. */
662 if (valtype == TREE_TYPE (t1) && ! p2)
663 return build_type_attribute_variant (t1, attributes);
664 if (valtype == TREE_TYPE (t2) && ! p1)
665 return build_type_attribute_variant (t2, attributes);
667 /* Simple way if one arg fails to specify argument types. */
668 if (p1 == NULL_TREE || TREE_VALUE (p1) == void_type_node)
670 rval = build_function_type (valtype, p2);
671 if ((raises = TYPE_RAISES_EXCEPTIONS (t2)))
672 rval = build_exception_variant (rval, raises);
673 return build_type_attribute_variant (rval, attributes);
675 raises = TYPE_RAISES_EXCEPTIONS (t1);
676 if (p2 == NULL_TREE || TREE_VALUE (p2) == void_type_node)
678 rval = build_function_type (valtype, p1);
680 rval = build_exception_variant (rval, raises);
681 return build_type_attribute_variant (rval, attributes);
684 rval = build_function_type (valtype, commonparms (p1, p2));
685 t1 = build_exception_variant (rval, raises);
691 /* Get this value the long way, since TYPE_METHOD_BASETYPE
692 is just the main variant of this. */
693 tree basetype = TREE_TYPE (TREE_VALUE (TYPE_ARG_TYPES (t2)));
694 tree raises = TYPE_RAISES_EXCEPTIONS (t1);
697 /* If this was a member function type, get back to the
698 original type of type member function (i.e., without
699 the class instance variable up front. */
700 t1 = build_function_type (TREE_TYPE (t1),
701 TREE_CHAIN (TYPE_ARG_TYPES (t1)));
702 t2 = build_function_type (TREE_TYPE (t2),
703 TREE_CHAIN (TYPE_ARG_TYPES (t2)));
704 t3 = merge_types (t1, t2);
705 t3 = build_cplus_method_type (basetype, TREE_TYPE (t3),
706 TYPE_ARG_TYPES (t3));
707 t1 = build_exception_variant (t3, raises);
713 return build_type_attribute_variant (t1, attributes);
716 /* Return the common type of two types.
717 We assume that comptypes has already been done and returned 1;
718 if that isn't so, this may crash.
720 This is the type for the result of most arithmetic operations
721 if the operands have the given two types. */
724 common_type (tree t1, tree t2)
726 enum tree_code code1;
727 enum tree_code code2;
729 /* If one type is nonsense, bail. */
730 if (t1 == error_mark_node || t2 == error_mark_node)
731 return error_mark_node;
733 code1 = TREE_CODE (t1);
734 code2 = TREE_CODE (t2);
736 if ((ARITHMETIC_TYPE_P (t1) || code1 == ENUMERAL_TYPE
737 || code1 == COMPLEX_TYPE)
738 && (ARITHMETIC_TYPE_P (t2) || code2 == ENUMERAL_TYPE
739 || code2 == COMPLEX_TYPE))
740 return type_after_usual_arithmetic_conversions (t1, t2);
742 else if ((TYPE_PTR_P (t1) && TYPE_PTR_P (t2))
743 || (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
744 || (TYPE_PTRMEMFUNC_P (t1) && TYPE_PTRMEMFUNC_P (t2)))
745 return composite_pointer_type (t1, t2, error_mark_node, error_mark_node,
751 /* Compare two exception specifier types for exactness or subsetness, if
752 allowed. Returns false for mismatch, true for match (same, or
755 [except.spec] "If a class X ... objects of class X or any class publicly
756 and unambiguously derived from X. Similarly, if a pointer type Y * ...
757 exceptions of type Y * or that are pointers to any type publicly and
758 unambiguously derived from Y. Otherwise a function only allows exceptions
759 that have the same type ..."
760 This does not mention cv qualifiers and is different to what throw
761 [except.throw] and catch [except.catch] will do. They will ignore the
762 top level cv qualifiers, and allow qualifiers in the pointer to class
765 We implement the letter of the standard. */
768 comp_except_types (tree a, tree b, bool exact)
770 if (same_type_p (a, b))
774 if (cp_type_quals (a) || cp_type_quals (b))
777 if (TREE_CODE (a) == POINTER_TYPE
778 && TREE_CODE (b) == POINTER_TYPE)
782 if (cp_type_quals (a) || cp_type_quals (b))
786 if (TREE_CODE (a) != RECORD_TYPE
787 || TREE_CODE (b) != RECORD_TYPE)
790 if (ACCESSIBLY_UNIQUELY_DERIVED_P (a, b))
796 /* Return true if TYPE1 and TYPE2 are equivalent exception specifiers.
797 If EXACT is false, T2 can be stricter than T1 (according to 15.4/7),
798 otherwise it must be exact. Exception lists are unordered, but
799 we've already filtered out duplicates. Most lists will be in order,
800 we should try to make use of that. */
803 comp_except_specs (tree t1, tree t2, bool exact)
812 if (t1 == NULL_TREE) /* T1 is ... */
813 return t2 == NULL_TREE || !exact;
814 if (!TREE_VALUE (t1)) /* t1 is EMPTY */
815 return t2 != NULL_TREE && !TREE_VALUE (t2);
816 if (t2 == NULL_TREE) /* T2 is ... */
818 if (TREE_VALUE (t1) && !TREE_VALUE (t2)) /* T2 is EMPTY, T1 is not */
821 /* Neither set is ... or EMPTY, make sure each part of T2 is in T1.
822 Count how many we find, to determine exactness. For exact matching and
823 ordered T1, T2, this is an O(n) operation, otherwise its worst case is
825 for (base = t1; t2 != NULL_TREE; t2 = TREE_CHAIN (t2))
827 for (probe = base; probe != NULL_TREE; probe = TREE_CHAIN (probe))
829 tree a = TREE_VALUE (probe);
830 tree b = TREE_VALUE (t2);
832 if (comp_except_types (a, b, exact))
834 if (probe == base && exact)
835 base = TREE_CHAIN (probe);
840 if (probe == NULL_TREE)
843 return !exact || base == NULL_TREE || length == list_length (t1);
846 /* Compare the array types T1 and T2. ALLOW_REDECLARATION is true if
847 [] can match [size]. */
850 comp_array_types (tree t1, tree t2, bool allow_redeclaration)
858 /* The type of the array elements must be the same. */
859 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
862 d1 = TYPE_DOMAIN (t1);
863 d2 = TYPE_DOMAIN (t2);
868 /* If one of the arrays is dimensionless, and the other has a
869 dimension, they are of different types. However, it is valid to
877 declarations for an array object can specify
878 array types that differ by the presence or absence of a major
879 array bound (_dcl.array_). */
881 return allow_redeclaration;
883 /* Check that the dimensions are the same. */
884 return (cp_tree_equal (TYPE_MIN_VALUE (d1), TYPE_MIN_VALUE (d2))
885 && cp_tree_equal (TYPE_MAX_VALUE (d1), TYPE_MAX_VALUE (d2)));
888 /* Return true if T1 and T2 are related as allowed by STRICT. STRICT
889 is a bitwise-or of the COMPARE_* flags. */
892 comptypes (tree t1, tree t2, int strict)
897 /* This should never happen. */
898 my_friendly_assert (t1 != error_mark_node, 307);
900 /* Suppress errors caused by previously reported errors */
901 if (t2 == error_mark_node)
904 my_friendly_assert (TYPE_P (t1) && TYPE_P (t2), 20030623);
906 /* TYPENAME_TYPEs should be resolved if the qualifying scope is the
907 current instantiation. */
908 if (TREE_CODE (t1) == TYPENAME_TYPE)
910 tree resolved = resolve_typename_type (t1, /*only_current_p=*/true);
912 if (resolved != error_mark_node)
916 if (TREE_CODE (t2) == TYPENAME_TYPE)
918 tree resolved = resolve_typename_type (t2, /*only_current_p=*/true);
920 if (resolved != error_mark_node)
924 /* If either type is the internal version of sizetype, use the
926 if (TREE_CODE (t1) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t1)
928 t1 = TYPE_DOMAIN (t1);
930 if (TREE_CODE (t2) == INTEGER_TYPE && TYPE_IS_SIZETYPE (t2)
932 t2 = TYPE_DOMAIN (t2);
934 if (TYPE_PTRMEMFUNC_P (t1))
935 t1 = TYPE_PTRMEMFUNC_FN_TYPE (t1);
936 if (TYPE_PTRMEMFUNC_P (t2))
937 t2 = TYPE_PTRMEMFUNC_FN_TYPE (t2);
939 /* Different classes of types can't be compatible. */
940 if (TREE_CODE (t1) != TREE_CODE (t2))
943 /* Qualifiers must match. */
944 if (cp_type_quals (t1) != cp_type_quals (t2))
946 if (TYPE_FOR_JAVA (t1) != TYPE_FOR_JAVA (t2))
949 /* Allow for two different type nodes which have essentially the same
950 definition. Note that we already checked for equality of the type
951 qualifiers (just above). */
953 if (TYPE_MAIN_VARIANT (t1) == TYPE_MAIN_VARIANT (t2))
956 if (!(*targetm.comp_type_attributes) (t1, t2))
959 switch (TREE_CODE (t1))
961 case TEMPLATE_TEMPLATE_PARM:
962 case BOUND_TEMPLATE_TEMPLATE_PARM:
963 if (TEMPLATE_TYPE_IDX (t1) != TEMPLATE_TYPE_IDX (t2)
964 || TEMPLATE_TYPE_LEVEL (t1) != TEMPLATE_TYPE_LEVEL (t2))
966 if (!comp_template_parms
967 (DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t1)),
968 DECL_TEMPLATE_PARMS (TEMPLATE_TEMPLATE_PARM_TEMPLATE_DECL (t2))))
970 if (TREE_CODE (t1) == TEMPLATE_TEMPLATE_PARM)
972 /* Don't check inheritance. */
973 strict = COMPARE_STRICT;
978 if (TYPE_TEMPLATE_INFO (t1) && TYPE_TEMPLATE_INFO (t2)
979 && (TYPE_TI_TEMPLATE (t1) == TYPE_TI_TEMPLATE (t2)
980 || TREE_CODE (t1) == BOUND_TEMPLATE_TEMPLATE_PARM)
981 && comp_template_args (TYPE_TI_ARGS (t1), TYPE_TI_ARGS (t2)))
984 if ((strict & COMPARE_BASE) && DERIVED_FROM_P (t1, t2))
986 else if ((strict & COMPARE_DERIVED) && DERIVED_FROM_P (t2, t1))
992 if (!comptypes (TYPE_OFFSET_BASETYPE (t1), TYPE_OFFSET_BASETYPE (t2),
993 strict & ~COMPARE_REDECLARATION))
999 return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
1003 if (!same_type_p (TREE_TYPE (t1), TREE_TYPE (t2)))
1005 return compparms (TYPE_ARG_TYPES (t1), TYPE_ARG_TYPES (t2));
1008 /* Target types must match incl. qualifiers. */
1009 return comp_array_types (t1, t2, !!(strict & COMPARE_REDECLARATION));
1011 case TEMPLATE_TYPE_PARM:
1012 return (TEMPLATE_TYPE_IDX (t1) == TEMPLATE_TYPE_IDX (t2)
1013 && TEMPLATE_TYPE_LEVEL (t1) == TEMPLATE_TYPE_LEVEL (t2));
1016 if (!cp_tree_equal (TYPENAME_TYPE_FULLNAME (t1),
1017 TYPENAME_TYPE_FULLNAME (t2)))
1019 return same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2));
1021 case UNBOUND_CLASS_TEMPLATE:
1022 if (!cp_tree_equal (TYPE_IDENTIFIER (t1), TYPE_IDENTIFIER (t2)))
1024 return same_type_p (TYPE_CONTEXT (t1), TYPE_CONTEXT (t2));
1027 return same_type_p (TREE_TYPE (t1), TREE_TYPE (t2));
1035 /* Returns 1 if TYPE1 is at least as qualified as TYPE2. */
1038 at_least_as_qualified_p (tree type1, tree type2)
1040 int q1 = cp_type_quals (type1);
1041 int q2 = cp_type_quals (type2);
1043 /* All qualifiers for TYPE2 must also appear in TYPE1. */
1044 return (q1 & q2) == q2;
1047 /* Returns 1 if TYPE1 is more qualified than TYPE2. */
1050 more_qualified_p (tree type1, tree type2)
1052 int q1 = cp_type_quals (type1);
1053 int q2 = cp_type_quals (type2);
1055 return q1 != q2 && (q1 & q2) == q2;
1058 /* Returns 1 if TYPE1 is more cv-qualified than TYPE2, -1 if TYPE2 is
1059 more cv-qualified that TYPE1, and 0 otherwise. */
1062 comp_cv_qualification (tree type1, tree type2)
1064 int q1 = cp_type_quals (type1);
1065 int q2 = cp_type_quals (type2);
1070 if ((q1 & q2) == q2)
1072 else if ((q1 & q2) == q1)
1078 /* Returns 1 if the cv-qualification signature of TYPE1 is a proper
1079 subset of the cv-qualification signature of TYPE2, and the types
1080 are similar. Returns -1 if the other way 'round, and 0 otherwise. */
1083 comp_cv_qual_signature (tree type1, tree type2)
1085 if (comp_ptr_ttypes_real (type2, type1, -1))
1087 else if (comp_ptr_ttypes_real (type1, type2, -1))
1093 /* If two types share a common base type, return that basetype.
1094 If there is not a unique most-derived base type, this function
1095 returns ERROR_MARK_NODE. */
1098 common_base_type (tree tt1, tree tt2)
1100 tree best = NULL_TREE;
1103 /* If one is a baseclass of another, that's good enough. */
1104 if (UNIQUELY_DERIVED_FROM_P (tt1, tt2))
1106 if (UNIQUELY_DERIVED_FROM_P (tt2, tt1))
1109 /* Otherwise, try to find a unique baseclass of TT1
1110 that is shared by TT2, and follow that down. */
1111 for (i = CLASSTYPE_N_BASECLASSES (tt1)-1; i >= 0; i--)
1113 tree basetype = TYPE_BINFO_BASETYPE (tt1, i);
1114 tree trial = common_base_type (basetype, tt2);
1117 if (trial == error_mark_node)
1119 if (best == NULL_TREE)
1121 else if (best != trial)
1122 return error_mark_node;
1127 for (i = CLASSTYPE_N_BASECLASSES (tt2)-1; i >= 0; i--)
1129 tree basetype = TYPE_BINFO_BASETYPE (tt2, i);
1130 tree trial = common_base_type (tt1, basetype);
1133 if (trial == error_mark_node)
1135 if (best == NULL_TREE)
1137 else if (best != trial)
1138 return error_mark_node;
1144 /* Subroutines of `comptypes'. */
1146 /* Return true if two parameter type lists PARMS1 and PARMS2 are
1147 equivalent in the sense that functions with those parameter types
1148 can have equivalent types. The two lists must be equivalent,
1149 element by element. */
1152 compparms (tree parms1, tree parms2)
1156 /* An unspecified parmlist matches any specified parmlist
1157 whose argument types don't need default promotions. */
1159 for (t1 = parms1, t2 = parms2;
1161 t1 = TREE_CHAIN (t1), t2 = TREE_CHAIN (t2))
1163 /* If one parmlist is shorter than the other,
1164 they fail to match. */
1167 if (!same_type_p (TREE_VALUE (t2), TREE_VALUE (t1)))
1175 cxx_sizeof_or_alignof_type (tree type, enum tree_code op, int complain)
1177 enum tree_code type_code;
1179 const char *op_name;
1181 my_friendly_assert (op == SIZEOF_EXPR || op == ALIGNOF_EXPR, 20020720);
1182 if (processing_template_decl)
1183 return build_min (op, size_type_node, type);
1185 op_name = operator_name_info[(int) op].name;
1187 type = non_reference (type);
1188 type_code = TREE_CODE (type);
1190 if (type_code == METHOD_TYPE)
1192 if (complain && (pedantic || warn_pointer_arith))
1193 pedwarn ("invalid application of `%s' to a member function", op_name);
1194 value = size_one_node;
1197 value = c_sizeof_or_alignof_type (complete_type (type), op, complain);
1203 expr_sizeof (tree e)
1205 if (processing_template_decl)
1206 return build_min (SIZEOF_EXPR, size_type_node, e);
1208 if (TREE_CODE (e) == COMPONENT_REF
1209 && DECL_C_BIT_FIELD (TREE_OPERAND (e, 1)))
1210 error ("sizeof applied to a bit-field");
1211 if (is_overloaded_fn (e))
1213 pedwarn ("ISO C++ forbids applying `sizeof' to an expression of function type");
1214 return c_sizeof (char_type_node);
1216 else if (type_unknown_p (e))
1218 cxx_incomplete_type_error (e, TREE_TYPE (e));
1219 return c_sizeof (char_type_node);
1222 if (e == error_mark_node)
1225 return cxx_sizeof (TREE_TYPE (e));
1229 /* Perform the conversions in [expr] that apply when an lvalue appears
1230 in an rvalue context: the lvalue-to-rvalue, array-to-pointer, and
1231 function-to-pointer conversions.
1233 In addition manifest constants are replaced by their values. */
1236 decay_conversion (tree exp)
1239 register enum tree_code code;
1241 type = TREE_TYPE (exp);
1242 code = TREE_CODE (type);
1244 if (code == REFERENCE_TYPE)
1246 exp = convert_from_reference (exp);
1247 type = TREE_TYPE (exp);
1248 code = TREE_CODE (type);
1251 if (type == error_mark_node)
1252 return error_mark_node;
1254 if (type_unknown_p (exp))
1256 cxx_incomplete_type_error (exp, TREE_TYPE (exp));
1257 return error_mark_node;
1260 /* Constants can be used directly unless they're not loadable. */
1261 if (TREE_CODE (exp) == CONST_DECL)
1262 exp = DECL_INITIAL (exp);
1263 /* Replace a nonvolatile const static variable with its value. We
1264 don't do this for arrays, though; we want the address of the
1265 first element of the array, not the address of the first element
1266 of its initializing constant. */
1267 else if (code != ARRAY_TYPE)
1269 exp = decl_constant_value (exp);
1270 type = TREE_TYPE (exp);
1273 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
1274 Leave such NOP_EXPRs, since RHS is being used in non-lvalue context. */
1276 if (code == VOID_TYPE)
1278 error ("void value not ignored as it ought to be");
1279 return error_mark_node;
1281 if (code == METHOD_TYPE)
1283 error ("invalid use of non-static member function");
1284 return error_mark_node;
1286 if (code == FUNCTION_TYPE || is_overloaded_fn (exp))
1287 return build_unary_op (ADDR_EXPR, exp, 0);
1288 if (code == ARRAY_TYPE)
1293 if (TREE_CODE (exp) == INDIRECT_REF)
1295 /* Stripping away the INDIRECT_REF is not the right
1296 thing to do for references... */
1297 tree inner = TREE_OPERAND (exp, 0);
1298 if (TREE_CODE (TREE_TYPE (inner)) == REFERENCE_TYPE)
1300 inner = build1 (CONVERT_EXPR,
1301 build_pointer_type (TREE_TYPE
1302 (TREE_TYPE (inner))),
1304 TREE_CONSTANT (inner) = TREE_CONSTANT (TREE_OPERAND (inner, 0));
1306 return cp_convert (build_pointer_type (TREE_TYPE (type)), inner);
1309 if (TREE_CODE (exp) == COMPOUND_EXPR)
1311 tree op1 = decay_conversion (TREE_OPERAND (exp, 1));
1312 return build (COMPOUND_EXPR, TREE_TYPE (op1),
1313 TREE_OPERAND (exp, 0), op1);
1317 && ! (TREE_CODE (exp) == CONSTRUCTOR && TREE_STATIC (exp)))
1319 error ("invalid use of non-lvalue array");
1320 return error_mark_node;
1323 ptrtype = build_pointer_type (TREE_TYPE (type));
1325 if (TREE_CODE (exp) == VAR_DECL)
1327 /* ??? This is not really quite correct
1328 in that the type of the operand of ADDR_EXPR
1329 is not the target type of the type of the ADDR_EXPR itself.
1330 Question is, can this lossage be avoided? */
1331 adr = build1 (ADDR_EXPR, ptrtype, exp);
1332 if (!cxx_mark_addressable (exp))
1333 return error_mark_node;
1334 TREE_CONSTANT (adr) = staticp (exp);
1335 TREE_SIDE_EFFECTS (adr) = 0; /* Default would be, same as EXP. */
1338 /* This way is better for a COMPONENT_REF since it can
1339 simplify the offset for a component. */
1340 adr = build_unary_op (ADDR_EXPR, exp, 1);
1341 return cp_convert (ptrtype, adr);
1344 /* [basic.lval]: Class rvalues can have cv-qualified types; non-class
1345 rvalues always have cv-unqualified types. */
1346 if (! CLASS_TYPE_P (type))
1347 exp = cp_convert (TYPE_MAIN_VARIANT (type), exp);
1353 default_conversion (tree exp)
1355 exp = decay_conversion (exp);
1357 if (INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (exp)))
1358 exp = perform_integral_promotions (exp);
1363 /* EXPR is an expression with an integral or enumeration type.
1364 Perform the integral promotions in [conv.prom], and return the
1368 perform_integral_promotions (tree expr)
1373 type = TREE_TYPE (expr);
1374 my_friendly_assert (INTEGRAL_OR_ENUMERATION_TYPE_P (type), 20030703);
1375 promoted_type = type_promotes_to (type);
1376 if (type != promoted_type)
1377 expr = cp_convert (promoted_type, expr);
1381 /* Take the address of an inline function without setting TREE_ADDRESSABLE
1385 inline_conversion (tree exp)
1387 if (TREE_CODE (exp) == FUNCTION_DECL)
1388 exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp);
1393 /* Returns nonzero iff exp is a STRING_CST or the result of applying
1394 decay_conversion to one. */
1397 string_conv_p (tree totype, tree exp, int warn)
1401 if (! flag_const_strings || TREE_CODE (totype) != POINTER_TYPE)
1404 t = TREE_TYPE (totype);
1405 if (!same_type_p (t, char_type_node)
1406 && !same_type_p (t, wchar_type_node))
1409 if (TREE_CODE (exp) == STRING_CST)
1411 /* Make sure that we don't try to convert between char and wchar_t. */
1412 if (!same_type_p (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_TYPE (exp))), t))
1417 /* Is this a string constant which has decayed to 'const char *'? */
1418 t = build_pointer_type (build_qualified_type (t, TYPE_QUAL_CONST));
1419 if (!same_type_p (TREE_TYPE (exp), t))
1422 if (TREE_CODE (exp) != ADDR_EXPR
1423 || TREE_CODE (TREE_OPERAND (exp, 0)) != STRING_CST)
1427 /* This warning is not very useful, as it complains about printf. */
1428 if (warn && warn_write_strings)
1429 warning ("deprecated conversion from string constant to `%T'", totype);
1434 /* Given a COND_EXPR, MIN_EXPR, or MAX_EXPR in T, return it in a form that we
1435 can, for example, use as an lvalue. This code used to be in
1436 unary_complex_lvalue, but we needed it to deal with `a = (d == c) ? b : c'
1437 expressions, where we're dealing with aggregates. But now it's again only
1438 called from unary_complex_lvalue. The case (in particular) that led to
1439 this was with CODE == ADDR_EXPR, since it's not an lvalue when we'd
1443 rationalize_conditional_expr (enum tree_code code, tree t)
1445 /* For MIN_EXPR or MAX_EXPR, fold-const.c has arranged things so that
1446 the first operand is always the one to be used if both operands
1447 are equal, so we know what conditional expression this used to be. */
1448 if (TREE_CODE (t) == MIN_EXPR || TREE_CODE (t) == MAX_EXPR)
1451 build_conditional_expr (build_x_binary_op ((TREE_CODE (t) == MIN_EXPR
1452 ? LE_EXPR : GE_EXPR),
1453 TREE_OPERAND (t, 0),
1454 TREE_OPERAND (t, 1)),
1455 build_unary_op (code, TREE_OPERAND (t, 0), 0),
1456 build_unary_op (code, TREE_OPERAND (t, 1), 0));
1460 build_conditional_expr (TREE_OPERAND (t, 0),
1461 build_unary_op (code, TREE_OPERAND (t, 1), 0),
1462 build_unary_op (code, TREE_OPERAND (t, 2), 0));
1465 /* Given the TYPE of an anonymous union field inside T, return the
1466 FIELD_DECL for the field. If not found return NULL_TREE. Because
1467 anonymous unions can nest, we must also search all anonymous unions
1468 that are directly reachable. */
1471 lookup_anon_field (tree t, tree type)
1475 for (field = TYPE_FIELDS (t); field; field = TREE_CHAIN (field))
1477 if (TREE_STATIC (field))
1479 if (TREE_CODE (field) != FIELD_DECL || DECL_ARTIFICIAL (field))
1482 /* If we find it directly, return the field. */
1483 if (DECL_NAME (field) == NULL_TREE
1484 && type == TYPE_MAIN_VARIANT (TREE_TYPE (field)))
1489 /* Otherwise, it could be nested, search harder. */
1490 if (DECL_NAME (field) == NULL_TREE
1491 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
1493 tree subfield = lookup_anon_field (TREE_TYPE (field), type);
1501 /* Build an expression representing OBJECT.MEMBER. OBJECT is an
1502 expression; MEMBER is a DECL or baselink. If ACCESS_PATH is
1503 non-NULL, it indicates the path to the base used to name MEMBER.
1504 If PRESERVE_REFERENCE is true, the expression returned will have
1505 REFERENCE_TYPE if the MEMBER does. Otherwise, the expression
1506 returned will have the type referred to by the reference.
1508 This function does not perform access control; that is either done
1509 earlier by the parser when the name of MEMBER is resolved to MEMBER
1510 itself, or later when overload resolution selects one of the
1511 functions indicated by MEMBER. */
1514 build_class_member_access_expr (tree object, tree member,
1515 tree access_path, bool preserve_reference)
1519 tree result = NULL_TREE;
1521 if (object == error_mark_node || member == error_mark_node)
1522 return error_mark_node;
1524 if (TREE_CODE (member) == PSEUDO_DTOR_EXPR)
1527 my_friendly_assert (DECL_P (member) || BASELINK_P (member),
1532 The type of the first expression shall be "class object" (of a
1534 object_type = TREE_TYPE (object);
1535 if (!complete_type_or_else (object_type, object))
1536 return error_mark_node;
1537 if (!CLASS_TYPE_P (object_type))
1539 error ("request for member `%D' in `%E', which is of non-class type `%T'",
1540 member, object, object_type);
1541 return error_mark_node;
1544 /* The standard does not seem to actually say that MEMBER must be a
1545 member of OBJECT_TYPE. However, that is clearly what is
1547 if (DECL_P (member))
1549 member_scope = DECL_CLASS_CONTEXT (member);
1551 if (TREE_DEPRECATED (member))
1552 warn_deprecated_use (member);
1555 member_scope = BINFO_TYPE (BASELINK_BINFO (member));
1556 /* If MEMBER is from an anonymous aggregate, MEMBER_SCOPE will
1557 presently be the anonymous union. Go outwards until we find a
1558 type related to OBJECT_TYPE. */
1559 while (ANON_AGGR_TYPE_P (member_scope)
1560 && !same_type_ignoring_top_level_qualifiers_p (member_scope,
1562 member_scope = TYPE_CONTEXT (member_scope);
1563 if (!member_scope || !DERIVED_FROM_P (member_scope, object_type))
1565 if (TREE_CODE (member) == FIELD_DECL)
1566 error ("invalid use of nonstatic data member '%E'", member);
1568 error ("`%D' is not a member of `%T'", member, object_type);
1569 return error_mark_node;
1572 /* Transform `(a, b).x' into `(*(a, &b)).x', `(a ? b : c).x' into
1573 `(*(a ? &b : &c)).x', and so on. A COND_EXPR is only an lvalue
1574 in the frontend; only _DECLs and _REFs are lvalues in the backend. */
1576 tree temp = unary_complex_lvalue (ADDR_EXPR, object);
1578 object = build_indirect_ref (temp, NULL);
1581 /* In [expr.ref], there is an explicit list of the valid choices for
1582 MEMBER. We check for each of those cases here. */
1583 if (TREE_CODE (member) == VAR_DECL)
1585 /* A static data member. */
1587 /* If OBJECT has side-effects, they are supposed to occur. */
1588 if (TREE_SIDE_EFFECTS (object))
1589 result = build (COMPOUND_EXPR, TREE_TYPE (result), object, result);
1591 else if (TREE_CODE (member) == FIELD_DECL)
1593 /* A non-static data member. */
1598 null_object_p = (TREE_CODE (object) == INDIRECT_REF
1599 && integer_zerop (TREE_OPERAND (object, 0)));
1601 /* Convert OBJECT to the type of MEMBER. */
1602 if (!same_type_p (TYPE_MAIN_VARIANT (object_type),
1603 TYPE_MAIN_VARIANT (member_scope)))
1608 binfo = lookup_base (access_path ? access_path : object_type,
1609 member_scope, ba_ignore, &kind);
1610 if (binfo == error_mark_node)
1611 return error_mark_node;
1613 /* It is invalid to try to get to a virtual base of a
1614 NULL object. The most common cause is invalid use of
1616 if (null_object_p && kind == bk_via_virtual)
1618 error ("invalid access to non-static data member `%D' of NULL object",
1620 error ("(perhaps the `offsetof' macro was used incorrectly)");
1621 return error_mark_node;
1624 /* Convert to the base. */
1625 object = build_base_path (PLUS_EXPR, object, binfo,
1627 /* If we found the base successfully then we should be able
1628 to convert to it successfully. */
1629 my_friendly_assert (object != error_mark_node,
1633 /* Complain about other invalid uses of offsetof, even though they will
1634 give the right answer. Note that we complain whether or not they
1635 actually used the offsetof macro, since there's no way to know at this
1636 point. So we just give a warning, instead of a pedwarn. */
1637 if (null_object_p && warn_invalid_offsetof
1638 && CLASSTYPE_NON_POD_P (object_type))
1640 warning ("invalid access to non-static data member `%D' of NULL object",
1642 warning ("(perhaps the `offsetof' macro was used incorrectly)");
1645 /* If MEMBER is from an anonymous aggregate, we have converted
1646 OBJECT so that it refers to the class containing the
1647 anonymous union. Generate a reference to the anonymous union
1648 itself, and recur to find MEMBER. */
1649 if (ANON_AGGR_TYPE_P (DECL_CONTEXT (member))
1650 /* When this code is called from build_field_call, the
1651 object already has the type of the anonymous union.
1652 That is because the COMPONENT_REF was already
1653 constructed, and was then disassembled before calling
1654 build_field_call. After the function-call code is
1655 cleaned up, this waste can be eliminated. */
1656 && (!same_type_ignoring_top_level_qualifiers_p
1657 (TREE_TYPE (object), DECL_CONTEXT (member))))
1659 tree anonymous_union;
1661 anonymous_union = lookup_anon_field (TREE_TYPE (object),
1662 DECL_CONTEXT (member));
1663 object = build_class_member_access_expr (object,
1665 /*access_path=*/NULL_TREE,
1666 preserve_reference);
1669 /* Compute the type of the field, as described in [expr.ref]. */
1670 type_quals = TYPE_UNQUALIFIED;
1671 member_type = TREE_TYPE (member);
1672 if (TREE_CODE (member_type) != REFERENCE_TYPE)
1674 type_quals = (cp_type_quals (member_type)
1675 | cp_type_quals (object_type));
1677 /* A field is const (volatile) if the enclosing object, or the
1678 field itself, is const (volatile). But, a mutable field is
1679 not const, even within a const object. */
1680 if (DECL_MUTABLE_P (member))
1681 type_quals &= ~TYPE_QUAL_CONST;
1682 member_type = cp_build_qualified_type (member_type, type_quals);
1685 result = fold (build (COMPONENT_REF, member_type, object, member));
1687 /* Mark the expression const or volatile, as appropriate. Even
1688 though we've dealt with the type above, we still have to mark the
1689 expression itself. */
1690 if (type_quals & TYPE_QUAL_CONST)
1691 TREE_READONLY (result) = 1;
1692 else if (type_quals & TYPE_QUAL_VOLATILE)
1693 TREE_THIS_VOLATILE (result) = 1;
1695 else if (BASELINK_P (member))
1697 /* The member is a (possibly overloaded) member function. */
1701 /* If the MEMBER is exactly one static member function, then we
1702 know the type of the expression. Otherwise, we must wait
1703 until overload resolution has been performed. */
1704 functions = BASELINK_FUNCTIONS (member);
1705 if (TREE_CODE (functions) == FUNCTION_DECL
1706 && DECL_STATIC_FUNCTION_P (functions))
1707 type = TREE_TYPE (functions);
1709 type = unknown_type_node;
1710 /* Note that we do not convert OBJECT to the BASELINK_BINFO
1711 base. That will happen when the function is called. */
1712 result = build (COMPONENT_REF, type, object, member);
1714 else if (TREE_CODE (member) == CONST_DECL)
1716 /* The member is an enumerator. */
1718 /* If OBJECT has side-effects, they are supposed to occur. */
1719 if (TREE_SIDE_EFFECTS (object))
1720 result = build (COMPOUND_EXPR, TREE_TYPE (result),
1725 error ("invalid use of `%D'", member);
1726 return error_mark_node;
1729 if (!preserve_reference)
1732 If E2 is declared to have type "reference to T", then ... the
1733 type of E1.E2 is T. */
1734 result = convert_from_reference (result);
1739 /* Return the destructor denoted by OBJECT.SCOPE::~DTOR_NAME, or, if
1740 SCOPE is NULL, by OBJECT.~DTOR_NAME. */
1743 lookup_destructor (tree object, tree scope, tree dtor_name)
1745 tree object_type = TREE_TYPE (object);
1746 tree dtor_type = TREE_OPERAND (dtor_name, 0);
1748 if (scope && !check_dtor_name (scope, dtor_name))
1750 error ("qualified type `%T' does not match destructor name `~%T'",
1752 return error_mark_node;
1754 if (!same_type_p (dtor_type, TYPE_MAIN_VARIANT (object_type)))
1756 error ("destructor name `%T' does not match type `%T' of expression",
1757 dtor_type, object_type);
1758 return error_mark_node;
1760 if (!TYPE_HAS_DESTRUCTOR (object_type))
1761 return build (PSEUDO_DTOR_EXPR, void_type_node, object, scope,
1763 return lookup_member (object_type, complete_dtor_identifier,
1764 /*protect=*/1, /*want_type=*/false);
1767 /* This function is called by the parser to process a class member
1768 access expression of the form OBJECT.NAME. NAME is a node used by
1769 the parser to represent a name; it is not yet a DECL. It may,
1770 however, be a BASELINK where the BASELINK_FUNCTIONS is a
1771 TEMPLATE_ID_EXPR. Templates must be looked up by the parser, and
1772 there is no reason to do the lookup twice, so the parser keeps the
1776 finish_class_member_access_expr (tree object, tree name)
1781 tree access_path = NULL_TREE;
1782 tree orig_object = object;
1783 tree orig_name = name;
1785 if (object == error_mark_node || name == error_mark_node)
1786 return error_mark_node;
1788 object_type = TREE_TYPE (object);
1790 if (processing_template_decl)
1792 if (/* If OBJECT_TYPE is dependent, so is OBJECT.NAME. */
1793 dependent_type_p (object_type)
1794 /* If NAME is "f<args>", where either 'f' or 'args' is
1795 dependent, then the expression is dependent. */
1796 || (TREE_CODE (name) == TEMPLATE_ID_EXPR
1797 && dependent_template_id_p (TREE_OPERAND (name, 0),
1798 TREE_OPERAND (name, 1)))
1799 /* If NAME is "T::X" where "T" is dependent, then the
1800 expression is dependent. */
1801 || (TREE_CODE (name) == SCOPE_REF
1802 && TYPE_P (TREE_OPERAND (name, 0))
1803 && dependent_type_p (TREE_OPERAND (name, 0))))
1804 return build_min_nt (COMPONENT_REF, object, name);
1805 object = build_non_dependent_expr (object);
1808 if (TREE_CODE (object_type) == REFERENCE_TYPE)
1810 object = convert_from_reference (object);
1811 object_type = TREE_TYPE (object);
1816 The type of the first expression shall be "class object" (of a
1818 if (!complete_type_or_else (object_type, object))
1819 return error_mark_node;
1820 if (!CLASS_TYPE_P (object_type))
1822 error ("request for member `%D' in `%E', which is of non-class type `%T'",
1823 name, object, object_type);
1824 return error_mark_node;
1827 if (BASELINK_P (name))
1829 /* A member function that has already been looked up. */
1830 my_friendly_assert ((TREE_CODE (BASELINK_FUNCTIONS (name))
1831 == TEMPLATE_ID_EXPR),
1837 bool is_template_id = false;
1838 tree template_args = NULL_TREE;
1841 if (TREE_CODE (name) == TEMPLATE_ID_EXPR)
1843 is_template_id = true;
1844 template_args = TREE_OPERAND (name, 1);
1845 name = TREE_OPERAND (name, 0);
1848 if (TREE_CODE (name) == SCOPE_REF)
1850 /* A qualified name. The qualifying class or namespace `S' has
1851 already been looked up; it is either a TYPE or a
1852 NAMESPACE_DECL. The member name is either an IDENTIFIER_NODE
1853 or a BIT_NOT_EXPR. */
1854 scope = TREE_OPERAND (name, 0);
1855 name = TREE_OPERAND (name, 1);
1856 my_friendly_assert ((CLASS_TYPE_P (scope)
1857 || TREE_CODE (scope) == NAMESPACE_DECL),
1859 my_friendly_assert ((TREE_CODE (name) == IDENTIFIER_NODE
1860 || TREE_CODE (name) == BIT_NOT_EXPR),
1863 /* If SCOPE is a namespace, then the qualified name does not
1864 name a member of OBJECT_TYPE. */
1865 if (TREE_CODE (scope) == NAMESPACE_DECL)
1867 error ("`%D::%D' is not a member of `%T'",
1868 scope, name, object_type);
1869 return error_mark_node;
1872 /* Find the base of OBJECT_TYPE corresponding to SCOPE. */
1873 access_path = lookup_base (object_type, scope, ba_check, NULL);
1874 if (!access_path || access_path == error_mark_node)
1875 return error_mark_node;
1880 access_path = object_type;
1883 if (TREE_CODE (name) == BIT_NOT_EXPR)
1884 member = lookup_destructor (object, scope, name);
1887 /* Look up the member. */
1888 member = lookup_member (access_path, name, /*protect=*/1,
1889 /*want_type=*/false);
1890 if (member == NULL_TREE)
1892 error ("'%D' has no member named '%E'", object_type, name);
1893 return error_mark_node;
1895 if (member == error_mark_node)
1896 return error_mark_node;
1901 tree template = member;
1903 if (BASELINK_P (template))
1904 template = lookup_template_function (template, template_args);
1907 error ("`%D' is not a member template function", name);
1908 return error_mark_node;
1913 if (TREE_DEPRECATED (member))
1914 warn_deprecated_use (member);
1916 expr = build_class_member_access_expr (object, member, access_path,
1917 /*preserve_reference=*/false);
1918 if (processing_template_decl && expr != error_mark_node)
1919 return build_min (COMPONENT_REF, TREE_TYPE (expr), orig_object,
1924 /* Return an expression for the MEMBER_NAME field in the internal
1925 representation of PTRMEM, a pointer-to-member function. (Each
1926 pointer-to-member function type gets its own RECORD_TYPE so it is
1927 more convenient to access the fields by name than by FIELD_DECL.)
1928 This routine converts the NAME to a FIELD_DECL and then creates the
1929 node for the complete expression. */
1932 build_ptrmemfunc_access_expr (tree ptrmem, tree member_name)
1938 /* This code is a stripped down version of
1939 build_class_member_access_expr. It does not work to use that
1940 routine directly because it expects the object to be of class
1942 ptrmem_type = TREE_TYPE (ptrmem);
1943 my_friendly_assert (TYPE_PTRMEMFUNC_P (ptrmem_type), 20020804);
1944 member = lookup_member (ptrmem_type, member_name, /*protect=*/0,
1945 /*want_type=*/false);
1946 member_type = cp_build_qualified_type (TREE_TYPE (member),
1947 cp_type_quals (ptrmem_type));
1948 return fold (build (COMPONENT_REF, member_type, ptrmem, member));
1951 /* Given an expression PTR for a pointer, return an expression
1952 for the value pointed to.
1953 ERRORSTRING is the name of the operator to appear in error messages.
1955 This function may need to overload OPERATOR_FNNAME.
1956 Must also handle REFERENCE_TYPEs for C++. */
1959 build_x_indirect_ref (tree expr, const char *errorstring)
1961 tree orig_expr = expr;
1964 if (processing_template_decl)
1966 if (type_dependent_expression_p (expr))
1967 return build_min_nt (INDIRECT_REF, expr);
1968 expr = build_non_dependent_expr (expr);
1971 rval = build_new_op (INDIRECT_REF, LOOKUP_NORMAL, expr, NULL_TREE,
1974 rval = build_indirect_ref (expr, errorstring);
1976 if (processing_template_decl && rval != error_mark_node)
1977 return build_min (INDIRECT_REF, TREE_TYPE (rval), orig_expr);
1983 build_indirect_ref (tree ptr, const char *errorstring)
1985 register tree pointer, type;
1987 if (ptr == error_mark_node)
1988 return error_mark_node;
1990 if (ptr == current_class_ptr)
1991 return current_class_ref;
1993 pointer = (TREE_CODE (TREE_TYPE (ptr)) == REFERENCE_TYPE
1994 ? ptr : decay_conversion (ptr));
1995 type = TREE_TYPE (pointer);
1997 if (TYPE_PTR_P (type) || TREE_CODE (type) == REFERENCE_TYPE)
2001 If the type of the expression is "pointer to T," the type
2002 of the result is "T."
2004 We must use the canonical variant because certain parts of
2005 the back end, like fold, do pointer comparisons between
2007 tree t = canonical_type_variant (TREE_TYPE (type));
2009 if (VOID_TYPE_P (t))
2011 /* A pointer to incomplete type (other than cv void) can be
2012 dereferenced [expr.unary.op]/1 */
2013 error ("`%T' is not a pointer-to-object type", type);
2014 return error_mark_node;
2016 else if (TREE_CODE (pointer) == ADDR_EXPR
2017 && same_type_p (t, TREE_TYPE (TREE_OPERAND (pointer, 0))))
2018 /* The POINTER was something like `&x'. We simplify `*&x' to
2020 return TREE_OPERAND (pointer, 0);
2023 tree ref = build1 (INDIRECT_REF, t, pointer);
2025 /* We *must* set TREE_READONLY when dereferencing a pointer to const,
2026 so that we get the proper error message if the result is used
2027 to assign to. Also, &* is supposed to be a no-op. */
2028 TREE_READONLY (ref) = CP_TYPE_CONST_P (t);
2029 TREE_THIS_VOLATILE (ref) = CP_TYPE_VOLATILE_P (t);
2030 TREE_SIDE_EFFECTS (ref)
2031 = (TREE_THIS_VOLATILE (ref) || TREE_SIDE_EFFECTS (pointer));
2035 /* `pointer' won't be an error_mark_node if we were given a
2036 pointer to member, so it's cool to check for this here. */
2037 else if (TYPE_PTR_TO_MEMBER_P (type))
2038 error ("invalid use of `%s' on pointer to member", errorstring);
2039 else if (pointer != error_mark_node)
2042 error ("invalid type argument of `%s'", errorstring);
2044 error ("invalid type argument");
2046 return error_mark_node;
2049 /* This handles expressions of the form "a[i]", which denotes
2052 This is logically equivalent in C to *(a+i), but we may do it differently.
2053 If A is a variable or a member, we generate a primitive ARRAY_REF.
2054 This avoids forcing the array out of registers, and can work on
2055 arrays that are not lvalues (for example, members of structures returned
2058 If INDEX is of some user-defined type, it must be converted to
2059 integer type. Otherwise, to make a compatible PLUS_EXPR, it
2060 will inherit the type of the array, which will be some pointer type. */
2063 build_array_ref (tree array, tree idx)
2067 error ("subscript missing in array reference");
2068 return error_mark_node;
2071 if (TREE_TYPE (array) == error_mark_node
2072 || TREE_TYPE (idx) == error_mark_node)
2073 return error_mark_node;
2075 /* If ARRAY is a COMPOUND_EXPR or COND_EXPR, move our reference
2077 switch (TREE_CODE (array))
2081 tree value = build_array_ref (TREE_OPERAND (array, 1), idx);
2082 return build (COMPOUND_EXPR, TREE_TYPE (value),
2083 TREE_OPERAND (array, 0), value);
2087 return build_conditional_expr
2088 (TREE_OPERAND (array, 0),
2089 build_array_ref (TREE_OPERAND (array, 1), idx),
2090 build_array_ref (TREE_OPERAND (array, 2), idx));
2096 if (TREE_CODE (TREE_TYPE (array)) == ARRAY_TYPE
2097 && TREE_CODE (array) != INDIRECT_REF)
2101 /* Subscripting with type char is likely to lose
2102 on a machine where chars are signed.
2103 So warn on any machine, but optionally.
2104 Don't warn for unsigned char since that type is safe.
2105 Don't warn for signed char because anyone who uses that
2106 must have done so deliberately. */
2107 if (warn_char_subscripts
2108 && TYPE_MAIN_VARIANT (TREE_TYPE (idx)) == char_type_node)
2109 warning ("array subscript has type `char'");
2111 if (!INTEGRAL_OR_ENUMERATION_TYPE_P (TREE_TYPE (idx)))
2113 error ("array subscript is not an integer");
2114 return error_mark_node;
2117 /* Apply integral promotions *after* noticing character types.
2118 (It is unclear why we do these promotions -- the standard
2119 does not say that we should. In fact, the natual thing would
2120 seem to be to convert IDX to ptrdiff_t; we're performing
2121 pointer arithmetic.) */
2122 idx = perform_integral_promotions (idx);
2124 /* An array that is indexed by a non-constant
2125 cannot be stored in a register; we must be able to do
2126 address arithmetic on its address.
2127 Likewise an array of elements of variable size. */
2128 if (TREE_CODE (idx) != INTEGER_CST
2129 || (COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (array)))
2130 && (TREE_CODE (TYPE_SIZE (TREE_TYPE (TREE_TYPE (array))))
2133 if (!cxx_mark_addressable (array))
2134 return error_mark_node;
2137 /* An array that is indexed by a constant value which is not within
2138 the array bounds cannot be stored in a register either; because we
2139 would get a crash in store_bit_field/extract_bit_field when trying
2140 to access a non-existent part of the register. */
2141 if (TREE_CODE (idx) == INTEGER_CST
2142 && TYPE_VALUES (TREE_TYPE (array))
2143 && ! int_fits_type_p (idx, TYPE_VALUES (TREE_TYPE (array))))
2145 if (!cxx_mark_addressable (array))
2146 return error_mark_node;
2149 if (pedantic && !lvalue_p (array))
2150 pedwarn ("ISO C++ forbids subscripting non-lvalue array");
2152 /* Note in C++ it is valid to subscript a `register' array, since
2153 it is valid to take the address of something with that
2154 storage specification. */
2158 while (TREE_CODE (foo) == COMPONENT_REF)
2159 foo = TREE_OPERAND (foo, 0);
2160 if (TREE_CODE (foo) == VAR_DECL && DECL_REGISTER (foo))
2161 warning ("subscripting array declared `register'");
2164 type = TREE_TYPE (TREE_TYPE (array));
2165 rval = build (ARRAY_REF, type, array, idx);
2166 /* Array ref is const/volatile if the array elements are
2167 or if the array is.. */
2168 TREE_READONLY (rval)
2169 |= (CP_TYPE_CONST_P (type) | TREE_READONLY (array));
2170 TREE_SIDE_EFFECTS (rval)
2171 |= (CP_TYPE_VOLATILE_P (type) | TREE_SIDE_EFFECTS (array));
2172 TREE_THIS_VOLATILE (rval)
2173 |= (CP_TYPE_VOLATILE_P (type) | TREE_THIS_VOLATILE (array));
2174 return require_complete_type (fold (rval));
2178 tree ar = default_conversion (array);
2179 tree ind = default_conversion (idx);
2181 /* Put the integer in IND to simplify error checking. */
2182 if (TREE_CODE (TREE_TYPE (ar)) == INTEGER_TYPE)
2189 if (ar == error_mark_node)
2192 if (TREE_CODE (TREE_TYPE (ar)) != POINTER_TYPE)
2194 error ("subscripted value is neither array nor pointer");
2195 return error_mark_node;
2197 if (TREE_CODE (TREE_TYPE (ind)) != INTEGER_TYPE)
2199 error ("array subscript is not an integer");
2200 return error_mark_node;
2203 return build_indirect_ref (cp_build_binary_op (PLUS_EXPR, ar, ind),
2208 /* Resolve a pointer to member function. INSTANCE is the object
2209 instance to use, if the member points to a virtual member.
2211 This used to avoid checking for virtual functions if basetype
2212 has no virtual functions, according to an earlier ANSI draft.
2213 With the final ISO C++ rules, such an optimization is
2214 incorrect: A pointer to a derived member can be static_cast
2215 to pointer-to-base-member, as long as the dynamic object
2216 later has the right member. */
2219 get_member_function_from_ptrfunc (tree *instance_ptrptr, tree function)
2221 if (TREE_CODE (function) == OFFSET_REF)
2222 function = TREE_OPERAND (function, 1);
2224 if (TYPE_PTRMEMFUNC_P (TREE_TYPE (function)))
2226 tree idx, delta, e1, e2, e3, vtbl, basetype;
2227 tree fntype = TYPE_PTRMEMFUNC_FN_TYPE (TREE_TYPE (function));
2229 tree instance_ptr = *instance_ptrptr;
2230 tree instance_save_expr = 0;
2231 if (instance_ptr == error_mark_node)
2233 if (TREE_CODE (function) == PTRMEM_CST)
2235 /* Extracting the function address from a pmf is only
2236 allowed with -Wno-pmf-conversions. It only works for
2238 e1 = build_addr_func (PTRMEM_CST_MEMBER (function));
2239 e1 = convert (fntype, e1);
2244 error ("object missing in use of `%E'", function);
2245 return error_mark_node;
2249 if (TREE_SIDE_EFFECTS (instance_ptr))
2250 instance_ptr = instance_save_expr = save_expr (instance_ptr);
2252 if (TREE_SIDE_EFFECTS (function))
2253 function = save_expr (function);
2255 /* Start by extracting all the information from the PMF itself. */
2256 e3 = PFN_FROM_PTRMEMFUNC (function);
2257 delta = build_ptrmemfunc_access_expr (function, delta_identifier);
2258 idx = build1 (NOP_EXPR, vtable_index_type, e3);
2259 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
2261 case ptrmemfunc_vbit_in_pfn:
2262 e1 = cp_build_binary_op (BIT_AND_EXPR, idx, integer_one_node);
2263 idx = cp_build_binary_op (MINUS_EXPR, idx, integer_one_node);
2266 case ptrmemfunc_vbit_in_delta:
2267 e1 = cp_build_binary_op (BIT_AND_EXPR, delta, integer_one_node);
2268 delta = cp_build_binary_op (RSHIFT_EXPR, delta, integer_one_node);
2275 /* Convert down to the right base before using the instance. First
2277 basetype = TYPE_METHOD_BASETYPE (TREE_TYPE (fntype));
2278 basetype = lookup_base (TREE_TYPE (TREE_TYPE (instance_ptr)),
2279 basetype, ba_check, NULL);
2280 instance_ptr = build_base_path (PLUS_EXPR, instance_ptr, basetype, 1);
2281 if (instance_ptr == error_mark_node)
2282 return error_mark_node;
2283 /* ...and then the delta in the PMF. */
2284 instance_ptr = build (PLUS_EXPR, TREE_TYPE (instance_ptr),
2285 instance_ptr, delta);
2287 /* Hand back the adjusted 'this' argument to our caller. */
2288 *instance_ptrptr = instance_ptr;
2290 /* Next extract the vtable pointer from the object. */
2291 vtbl = build1 (NOP_EXPR, build_pointer_type (vtbl_ptr_type_node),
2293 vtbl = build_indirect_ref (vtbl, NULL);
2295 /* Finally, extract the function pointer from the vtable. */
2296 e2 = fold (build (PLUS_EXPR, TREE_TYPE (vtbl), vtbl, idx));
2297 e2 = build_indirect_ref (e2, NULL);
2298 TREE_CONSTANT (e2) = 1;
2300 /* When using function descriptors, the address of the
2301 vtable entry is treated as a function pointer. */
2302 if (TARGET_VTABLE_USES_DESCRIPTORS)
2303 e2 = build1 (NOP_EXPR, TREE_TYPE (e2),
2304 build_unary_op (ADDR_EXPR, e2, /*noconvert=*/1));
2306 TREE_TYPE (e2) = TREE_TYPE (e3);
2307 e1 = build_conditional_expr (e1, e2, e3);
2309 /* Make sure this doesn't get evaluated first inside one of the
2310 branches of the COND_EXPR. */
2311 if (instance_save_expr)
2312 e1 = build (COMPOUND_EXPR, TREE_TYPE (e1),
2313 instance_save_expr, e1);
2321 build_function_call (tree function, tree params)
2323 register tree fntype, fndecl;
2324 register tree coerced_params;
2326 tree name = NULL_TREE, assembler_name = NULL_TREE;
2328 tree original = function;
2330 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2331 Strip such NOP_EXPRs, since FUNCTION is used in non-lvalue context. */
2332 if (TREE_CODE (function) == NOP_EXPR
2333 && TREE_TYPE (function) == TREE_TYPE (TREE_OPERAND (function, 0)))
2334 function = TREE_OPERAND (function, 0);
2336 if (TREE_CODE (function) == FUNCTION_DECL)
2338 name = DECL_NAME (function);
2339 assembler_name = DECL_ASSEMBLER_NAME (function);
2341 mark_used (function);
2344 /* Convert anything with function type to a pointer-to-function. */
2345 if (pedantic && DECL_MAIN_P (function))
2346 pedwarn ("ISO C++ forbids calling `::main' from within program");
2348 /* Differs from default_conversion by not setting TREE_ADDRESSABLE
2349 (because calling an inline function does not mean the function
2350 needs to be separately compiled). */
2352 if (DECL_INLINE (function))
2353 function = inline_conversion (function);
2355 function = build_addr_func (function);
2361 function = build_addr_func (function);
2364 if (function == error_mark_node)
2365 return error_mark_node;
2367 fntype = TREE_TYPE (function);
2369 if (TYPE_PTRMEMFUNC_P (fntype))
2371 error ("must use .* or ->* to call pointer-to-member function in `%E (...)'",
2373 return error_mark_node;
2376 is_method = (TREE_CODE (fntype) == POINTER_TYPE
2377 && TREE_CODE (TREE_TYPE (fntype)) == METHOD_TYPE);
2379 if (!((TREE_CODE (fntype) == POINTER_TYPE
2380 && TREE_CODE (TREE_TYPE (fntype)) == FUNCTION_TYPE)
2382 || TREE_CODE (function) == TEMPLATE_ID_EXPR))
2384 error ("`%E' cannot be used as a function", original);
2385 return error_mark_node;
2388 /* fntype now gets the type of function pointed to. */
2389 fntype = TREE_TYPE (fntype);
2391 /* Convert the parameters to the types declared in the
2392 function prototype, or apply default promotions. */
2394 coerced_params = convert_arguments (TYPE_ARG_TYPES (fntype),
2395 params, fndecl, LOOKUP_NORMAL);
2396 if (coerced_params == error_mark_node)
2397 return error_mark_node;
2399 /* Check for errors in format strings. */
2402 check_function_format (NULL, TYPE_ATTRIBUTES (fntype), coerced_params);
2404 /* Recognize certain built-in functions so we can make tree-codes
2405 other than CALL_EXPR. We do this when it enables fold-const.c
2406 to do something useful. */
2408 if (TREE_CODE (function) == ADDR_EXPR
2409 && TREE_CODE (TREE_OPERAND (function, 0)) == FUNCTION_DECL
2410 && DECL_BUILT_IN (TREE_OPERAND (function, 0)))
2412 result = expand_tree_builtin (TREE_OPERAND (function, 0),
2413 params, coerced_params);
2418 return build_cxx_call (function, params, coerced_params);
2421 /* Convert the actual parameter expressions in the list VALUES
2422 to the types in the list TYPELIST.
2423 If parmdecls is exhausted, or when an element has NULL as its type,
2424 perform the default conversions.
2426 NAME is an IDENTIFIER_NODE or 0. It is used only for error messages.
2428 This is also where warnings about wrong number of args are generated.
2430 Return a list of expressions for the parameters as converted.
2432 Both VALUES and the returned value are chains of TREE_LIST nodes
2433 with the elements of the list in the TREE_VALUE slots of those nodes.
2435 In C++, unspecified trailing parameters can be filled in with their
2436 default arguments, if such were specified. Do so here. */
2439 convert_arguments (tree typelist, tree values, tree fndecl, int flags)
2441 register tree typetail, valtail;
2442 register tree result = NULL_TREE;
2443 const char *called_thing = 0;
2446 /* Argument passing is always copy-initialization. */
2447 flags |= LOOKUP_ONLYCONVERTING;
2451 if (TREE_CODE (TREE_TYPE (fndecl)) == METHOD_TYPE)
2453 if (DECL_NAME (fndecl) == NULL_TREE
2454 || IDENTIFIER_HAS_TYPE_VALUE (DECL_NAME (fndecl)))
2455 called_thing = "constructor";
2457 called_thing = "member function";
2460 called_thing = "function";
2463 for (valtail = values, typetail = typelist;
2465 valtail = TREE_CHAIN (valtail), i++)
2467 register tree type = typetail ? TREE_VALUE (typetail) : 0;
2468 register tree val = TREE_VALUE (valtail);
2470 if (val == error_mark_node)
2471 return error_mark_node;
2473 if (type == void_type_node)
2477 cp_error_at ("too many arguments to %s `%+#D'", called_thing,
2479 error ("at this point in file");
2482 error ("too many arguments to function");
2483 /* In case anybody wants to know if this argument
2486 TREE_TYPE (tree_last (result)) = error_mark_node;
2490 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
2491 Strip such NOP_EXPRs, since VAL is used in non-lvalue context. */
2492 if (TREE_CODE (val) == NOP_EXPR
2493 && TREE_TYPE (val) == TREE_TYPE (TREE_OPERAND (val, 0))
2494 && (type == 0 || TREE_CODE (type) != REFERENCE_TYPE))
2495 val = TREE_OPERAND (val, 0);
2497 if (type == 0 || TREE_CODE (type) != REFERENCE_TYPE)
2499 if (TREE_CODE (TREE_TYPE (val)) == ARRAY_TYPE
2500 || TREE_CODE (TREE_TYPE (val)) == FUNCTION_TYPE
2501 || TREE_CODE (TREE_TYPE (val)) == METHOD_TYPE)
2502 val = decay_conversion (val);
2505 if (val == error_mark_node)
2506 return error_mark_node;
2510 /* Formal parm type is specified by a function prototype. */
2513 if (!COMPLETE_TYPE_P (complete_type (type)))
2515 error ("parameter type of called function is incomplete");
2520 parmval = convert_for_initialization
2521 (NULL_TREE, type, val, flags,
2522 "argument passing", fndecl, i);
2523 parmval = convert_for_arg_passing (type, parmval);
2526 if (parmval == error_mark_node)
2527 return error_mark_node;
2529 result = tree_cons (NULL_TREE, parmval, result);
2533 if (TREE_CODE (TREE_TYPE (val)) == REFERENCE_TYPE)
2534 val = convert_from_reference (val);
2536 if (fndecl && DECL_BUILT_IN (fndecl)
2537 && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P)
2538 /* Don't do ellipsis conversion for __built_in_constant_p
2539 as this will result in spurious warnings for non-POD
2541 val = require_complete_type (val);
2543 val = convert_arg_to_ellipsis (val);
2545 result = tree_cons (NULL_TREE, val, result);
2549 typetail = TREE_CHAIN (typetail);
2552 if (typetail != 0 && typetail != void_list_node)
2554 /* See if there are default arguments that can be used */
2555 if (TREE_PURPOSE (typetail)
2556 && TREE_CODE (TREE_PURPOSE (typetail)) != DEFAULT_ARG)
2558 for (; typetail != void_list_node; ++i)
2561 = convert_default_arg (TREE_VALUE (typetail),
2562 TREE_PURPOSE (typetail),
2565 if (parmval == error_mark_node)
2566 return error_mark_node;
2568 result = tree_cons (0, parmval, result);
2569 typetail = TREE_CHAIN (typetail);
2570 /* ends with `...'. */
2571 if (typetail == NULL_TREE)
2579 cp_error_at ("too few arguments to %s `%+#D'",
2580 called_thing, fndecl);
2581 error ("at this point in file");
2584 error ("too few arguments to function");
2585 return error_mark_list;
2589 return nreverse (result);
2592 /* Build a binary-operation expression, after performing default
2593 conversions on the operands. CODE is the kind of expression to build. */
2596 build_x_binary_op (enum tree_code code, tree arg1, tree arg2)
2605 if (processing_template_decl)
2607 if (type_dependent_expression_p (arg1)
2608 || type_dependent_expression_p (arg2))
2609 return build_min_nt (code, arg1, arg2);
2610 arg1 = build_non_dependent_expr (arg1);
2611 arg2 = build_non_dependent_expr (arg2);
2614 if (code == DOTSTAR_EXPR)
2615 expr = build_m_component_ref (arg1, arg2);
2617 expr = build_new_op (code, LOOKUP_NORMAL, arg1, arg2, NULL_TREE);
2619 if (processing_template_decl && expr != error_mark_node)
2620 return build_min (code, TREE_TYPE (expr), orig_arg1, orig_arg2);
2625 /* Build a binary-operation expression without default conversions.
2626 CODE is the kind of expression to build.
2627 This function differs from `build' in several ways:
2628 the data type of the result is computed and recorded in it,
2629 warnings are generated if arg data types are invalid,
2630 special handling for addition and subtraction of pointers is known,
2631 and some optimization is done (operations on narrow ints
2632 are done in the narrower type when that gives the same result).
2633 Constant folding is also done before the result is returned.
2635 Note that the operands will never have enumeral types
2636 because either they have just had the default conversions performed
2637 or they have both just been converted to some other type in which
2638 the arithmetic is to be done.
2640 C++: must do special pointer arithmetic when implementing
2641 multiple inheritance, and deal with pointer to member functions. */
2644 build_binary_op (enum tree_code code, tree orig_op0, tree orig_op1,
2645 int convert_p ATTRIBUTE_UNUSED)
2648 register enum tree_code code0, code1;
2651 /* Expression code to give to the expression when it is built.
2652 Normally this is CODE, which is what the caller asked for,
2653 but in some special cases we change it. */
2654 register enum tree_code resultcode = code;
2656 /* Data type in which the computation is to be performed.
2657 In the simplest cases this is the common type of the arguments. */
2658 register tree result_type = NULL;
2660 /* Nonzero means operands have already been type-converted
2661 in whatever way is necessary.
2662 Zero means they need to be converted to RESULT_TYPE. */
2665 /* Nonzero means create the expression with this type, rather than
2667 tree build_type = 0;
2669 /* Nonzero means after finally constructing the expression
2670 convert it to this type. */
2671 tree final_type = 0;
2673 /* Nonzero if this is an operation like MIN or MAX which can
2674 safely be computed in short if both args are promoted shorts.
2675 Also implies COMMON.
2676 -1 indicates a bitwise operation; this makes a difference
2677 in the exact conditions for when it is safe to do the operation
2678 in a narrower mode. */
2681 /* Nonzero if this is a comparison operation;
2682 if both args are promoted shorts, compare the original shorts.
2683 Also implies COMMON. */
2684 int short_compare = 0;
2686 /* Nonzero if this is a right-shift operation, which can be computed on the
2687 original short and then promoted if the operand is a promoted short. */
2688 int short_shift = 0;
2690 /* Nonzero means set RESULT_TYPE to the common type of the args. */
2693 /* Apply default conversions. */
2697 if (code == TRUTH_AND_EXPR || code == TRUTH_ANDIF_EXPR
2698 || code == TRUTH_OR_EXPR || code == TRUTH_ORIF_EXPR
2699 || code == TRUTH_XOR_EXPR)
2701 if (!really_overloaded_fn (op0))
2702 op0 = decay_conversion (op0);
2703 if (!really_overloaded_fn (op1))
2704 op1 = decay_conversion (op1);
2708 if (!really_overloaded_fn (op0))
2709 op0 = default_conversion (op0);
2710 if (!really_overloaded_fn (op1))
2711 op1 = default_conversion (op1);
2714 /* Strip NON_LVALUE_EXPRs, etc., since we aren't using as an lvalue. */
2715 STRIP_TYPE_NOPS (op0);
2716 STRIP_TYPE_NOPS (op1);
2718 /* DTRT if one side is an overloaded function, but complain about it. */
2719 if (type_unknown_p (op0))
2721 tree t = instantiate_type (TREE_TYPE (op1), op0, tf_none);
2722 if (t != error_mark_node)
2724 pedwarn ("assuming cast to type `%T' from overloaded function",
2729 if (type_unknown_p (op1))
2731 tree t = instantiate_type (TREE_TYPE (op0), op1, tf_none);
2732 if (t != error_mark_node)
2734 pedwarn ("assuming cast to type `%T' from overloaded function",
2740 type0 = TREE_TYPE (op0);
2741 type1 = TREE_TYPE (op1);
2743 /* The expression codes of the data types of the arguments tell us
2744 whether the arguments are integers, floating, pointers, etc. */
2745 code0 = TREE_CODE (type0);
2746 code1 = TREE_CODE (type1);
2748 /* If an error was already reported for one of the arguments,
2749 avoid reporting another error. */
2751 if (code0 == ERROR_MARK || code1 == ERROR_MARK)
2752 return error_mark_node;
2757 /* Handle the pointer + int case. */
2758 if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2759 return cp_pointer_int_sum (PLUS_EXPR, op0, op1);
2760 else if (code1 == POINTER_TYPE && code0 == INTEGER_TYPE)
2761 return cp_pointer_int_sum (PLUS_EXPR, op1, op0);
2767 /* Subtraction of two similar pointers.
2768 We must subtract them as integers, then divide by object size. */
2769 if (code0 == POINTER_TYPE && code1 == POINTER_TYPE
2770 && same_type_ignoring_top_level_qualifiers_p (TREE_TYPE (type0),
2772 return pointer_diff (op0, op1, common_type (type0, type1));
2773 /* Handle pointer minus int. Just like pointer plus int. */
2774 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2775 return cp_pointer_int_sum (MINUS_EXPR, op0, op1);
2784 case TRUNC_DIV_EXPR:
2786 case FLOOR_DIV_EXPR:
2787 case ROUND_DIV_EXPR:
2788 case EXACT_DIV_EXPR:
2789 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2790 || code0 == COMPLEX_TYPE)
2791 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2792 || code1 == COMPLEX_TYPE))
2794 if (TREE_CODE (op1) == INTEGER_CST && integer_zerop (op1))
2795 warning ("division by zero in `%E / 0'", op0);
2796 else if (TREE_CODE (op1) == REAL_CST && real_zerop (op1))
2797 warning ("division by zero in `%E / 0.'", op0);
2799 if (!(code0 == INTEGER_TYPE && code1 == INTEGER_TYPE))
2800 resultcode = RDIV_EXPR;
2802 /* When dividing two signed integers, we have to promote to int.
2803 unless we divide by a constant != -1. Note that default
2804 conversion will have been performed on the operands at this
2805 point, so we have to dig out the original type to find out if
2807 shorten = ((TREE_CODE (op0) == NOP_EXPR
2808 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2809 || (TREE_CODE (op1) == INTEGER_CST
2810 && ! integer_all_onesp (op1)));
2817 case BIT_ANDTC_EXPR:
2820 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2824 case TRUNC_MOD_EXPR:
2825 case FLOOR_MOD_EXPR:
2826 if (code1 == INTEGER_TYPE && integer_zerop (op1))
2827 warning ("division by zero in `%E %% 0'", op0);
2828 else if (code1 == REAL_TYPE && real_zerop (op1))
2829 warning ("division by zero in `%E %% 0.'", op0);
2831 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2833 /* Although it would be tempting to shorten always here, that loses
2834 on some targets, since the modulo instruction is undefined if the
2835 quotient can't be represented in the computation mode. We shorten
2836 only if unsigned or if dividing by something we know != -1. */
2837 shorten = ((TREE_CODE (op0) == NOP_EXPR
2838 && TREE_UNSIGNED (TREE_TYPE (TREE_OPERAND (op0, 0))))
2839 || (TREE_CODE (op1) == INTEGER_CST
2840 && ! integer_all_onesp (op1)));
2845 case TRUTH_ANDIF_EXPR:
2846 case TRUTH_ORIF_EXPR:
2847 case TRUTH_AND_EXPR:
2849 result_type = boolean_type_node;
2852 /* Shift operations: result has same type as first operand;
2853 always convert second operand to int.
2854 Also set SHORT_SHIFT if shifting rightward. */
2857 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2859 result_type = type0;
2860 if (TREE_CODE (op1) == INTEGER_CST)
2862 if (tree_int_cst_lt (op1, integer_zero_node))
2863 warning ("right shift count is negative");
2866 if (! integer_zerop (op1))
2868 if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2869 warning ("right shift count >= width of type");
2872 /* Convert the shift-count to an integer, regardless of
2873 size of value being shifted. */
2874 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2875 op1 = cp_convert (integer_type_node, op1);
2876 /* Avoid converting op1 to result_type later. */
2882 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2884 result_type = type0;
2885 if (TREE_CODE (op1) == INTEGER_CST)
2887 if (tree_int_cst_lt (op1, integer_zero_node))
2888 warning ("left shift count is negative");
2889 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2890 warning ("left shift count >= width of type");
2892 /* Convert the shift-count to an integer, regardless of
2893 size of value being shifted. */
2894 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2895 op1 = cp_convert (integer_type_node, op1);
2896 /* Avoid converting op1 to result_type later. */
2903 if (code0 == INTEGER_TYPE && code1 == INTEGER_TYPE)
2905 result_type = type0;
2906 if (TREE_CODE (op1) == INTEGER_CST)
2908 if (tree_int_cst_lt (op1, integer_zero_node))
2909 warning ("%s rotate count is negative",
2910 (code == LROTATE_EXPR) ? "left" : "right");
2911 else if (compare_tree_int (op1, TYPE_PRECISION (type0)) >= 0)
2912 warning ("%s rotate count >= width of type",
2913 (code == LROTATE_EXPR) ? "left" : "right");
2915 /* Convert the shift-count to an integer, regardless of
2916 size of value being shifted. */
2917 if (TYPE_MAIN_VARIANT (TREE_TYPE (op1)) != integer_type_node)
2918 op1 = cp_convert (integer_type_node, op1);
2924 if (warn_float_equal && (code0 == REAL_TYPE || code1 == REAL_TYPE))
2925 warning ("comparing floating point with == or != is unsafe");
2927 build_type = boolean_type_node;
2928 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE
2929 || code0 == COMPLEX_TYPE)
2930 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE
2931 || code1 == COMPLEX_TYPE))
2933 else if ((code0 == POINTER_TYPE && code1 == POINTER_TYPE)
2934 || (TYPE_PTRMEM_P (type0) && TYPE_PTRMEM_P (type1)))
2935 result_type = composite_pointer_type (type0, type1, op0, op1,
2937 else if ((code0 == POINTER_TYPE || TYPE_PTRMEM_P (type0))
2938 && null_ptr_cst_p (op1))
2939 result_type = type0;
2940 else if ((code1 == POINTER_TYPE || TYPE_PTRMEM_P (type1))
2941 && null_ptr_cst_p (op0))
2942 result_type = type1;
2943 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
2945 result_type = type0;
2946 error ("ISO C++ forbids comparison between pointer and integer");
2948 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
2950 result_type = type1;
2951 error ("ISO C++ forbids comparison between pointer and integer");
2953 else if (TYPE_PTRMEMFUNC_P (type0) && null_ptr_cst_p (op1))
2955 op0 = build_ptrmemfunc_access_expr (op0, pfn_identifier);
2956 op1 = cp_convert (TREE_TYPE (op0), integer_zero_node);
2957 result_type = TREE_TYPE (op0);
2959 else if (TYPE_PTRMEMFUNC_P (type1) && null_ptr_cst_p (op0))
2960 return cp_build_binary_op (code, op1, op0);
2961 else if (TYPE_PTRMEMFUNC_P (type0) && TYPE_PTRMEMFUNC_P (type1)
2962 && same_type_p (type0, type1))
2964 /* E will be the final comparison. */
2966 /* E1 and E2 are for scratch. */
2974 if (TREE_SIDE_EFFECTS (op0))
2975 op0 = save_expr (op0);
2976 if (TREE_SIDE_EFFECTS (op1))
2977 op1 = save_expr (op1);
2982 && (!op0.pfn || op0.delta == op1.delta))
2984 The reason for the `!op0.pfn' bit is that a NULL
2985 pointer-to-member is any member with a zero PFN; the
2986 DELTA field is unspecified. */
2987 pfn0 = pfn_from_ptrmemfunc (op0);
2988 pfn1 = pfn_from_ptrmemfunc (op1);
2989 delta0 = build_ptrmemfunc_access_expr (op0,
2991 delta1 = build_ptrmemfunc_access_expr (op1,
2993 e1 = cp_build_binary_op (EQ_EXPR, delta0, delta1);
2994 e2 = cp_build_binary_op (EQ_EXPR,
2996 cp_convert (TREE_TYPE (pfn0),
2997 integer_zero_node));
2998 e1 = cp_build_binary_op (TRUTH_ORIF_EXPR, e1, e2);
2999 e2 = build (EQ_EXPR, boolean_type_node, pfn0, pfn1);
3000 e = cp_build_binary_op (TRUTH_ANDIF_EXPR, e2, e1);
3001 if (code == EQ_EXPR)
3003 return cp_build_binary_op (EQ_EXPR, e, integer_zero_node);
3005 else if ((TYPE_PTRMEMFUNC_P (type0)
3006 && same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type0), type1))
3007 || (TYPE_PTRMEMFUNC_P (type1)
3008 && same_type_p (TYPE_PTRMEMFUNC_FN_TYPE (type1), type0)))
3014 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3015 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3017 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3018 result_type = composite_pointer_type (type0, type1, op0, op1,
3026 build_type = boolean_type_node;
3027 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE)
3028 && (code1 == INTEGER_TYPE || code1 == REAL_TYPE))
3030 else if (code0 == POINTER_TYPE && code1 == POINTER_TYPE)
3031 result_type = composite_pointer_type (type0, type1, op0, op1,
3033 else if (code0 == POINTER_TYPE && TREE_CODE (op1) == INTEGER_CST
3034 && integer_zerop (op1))
3035 result_type = type0;
3036 else if (code1 == POINTER_TYPE && TREE_CODE (op0) == INTEGER_CST
3037 && integer_zerop (op0))
3038 result_type = type1;
3039 else if (code0 == POINTER_TYPE && code1 == INTEGER_TYPE)
3041 result_type = type0;
3042 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3044 else if (code0 == INTEGER_TYPE && code1 == POINTER_TYPE)
3046 result_type = type1;
3047 pedwarn ("ISO C++ forbids comparison between pointer and integer");
3051 case UNORDERED_EXPR:
3058 build_type = integer_type_node;
3059 if (code0 != REAL_TYPE || code1 != REAL_TYPE)
3061 error ("unordered comparison on non-floating point argument");
3062 return error_mark_node;
3071 if ((code0 == INTEGER_TYPE || code0 == REAL_TYPE || code0 == COMPLEX_TYPE)
3073 (code1 == INTEGER_TYPE || code1 == REAL_TYPE || code1 == COMPLEX_TYPE))
3075 int none_complex = (code0 != COMPLEX_TYPE && code1 != COMPLEX_TYPE);
3077 if (shorten || common || short_compare)
3078 result_type = common_type (type0, type1);
3080 /* For certain operations (which identify themselves by shorten != 0)
3081 if both args were extended from the same smaller type,
3082 do the arithmetic in that type and then extend.
3084 shorten !=0 and !=1 indicates a bitwise operation.
3085 For them, this optimization is safe only if
3086 both args are zero-extended or both are sign-extended.
3087 Otherwise, we might change the result.
3088 Eg, (short)-1 | (unsigned short)-1 is (int)-1
3089 but calculated in (unsigned short) it would be (unsigned short)-1. */
3091 if (shorten && none_complex)
3093 int unsigned0, unsigned1;
3094 tree arg0 = get_narrower (op0, &unsigned0);
3095 tree arg1 = get_narrower (op1, &unsigned1);
3096 /* UNS is 1 if the operation to be done is an unsigned one. */
3097 int uns = TREE_UNSIGNED (result_type);
3100 final_type = result_type;
3102 /* Handle the case that OP0 does not *contain* a conversion
3103 but it *requires* conversion to FINAL_TYPE. */
3105 if (op0 == arg0 && TREE_TYPE (op0) != final_type)
3106 unsigned0 = TREE_UNSIGNED (TREE_TYPE (op0));
3107 if (op1 == arg1 && TREE_TYPE (op1) != final_type)
3108 unsigned1 = TREE_UNSIGNED (TREE_TYPE (op1));
3110 /* Now UNSIGNED0 is 1 if ARG0 zero-extends to FINAL_TYPE. */
3112 /* For bitwise operations, signedness of nominal type
3113 does not matter. Consider only how operands were extended. */
3117 /* Note that in all three cases below we refrain from optimizing
3118 an unsigned operation on sign-extended args.
3119 That would not be valid. */
3121 /* Both args variable: if both extended in same way
3122 from same width, do it in that width.
3123 Do it unsigned if args were zero-extended. */
3124 if ((TYPE_PRECISION (TREE_TYPE (arg0))
3125 < TYPE_PRECISION (result_type))
3126 && (TYPE_PRECISION (TREE_TYPE (arg1))
3127 == TYPE_PRECISION (TREE_TYPE (arg0)))
3128 && unsigned0 == unsigned1
3129 && (unsigned0 || !uns))
3130 result_type = c_common_signed_or_unsigned_type
3131 (unsigned0, common_type (TREE_TYPE (arg0), TREE_TYPE (arg1)));
3132 else if (TREE_CODE (arg0) == INTEGER_CST
3133 && (unsigned1 || !uns)
3134 && (TYPE_PRECISION (TREE_TYPE (arg1))
3135 < TYPE_PRECISION (result_type))
3136 && (type = c_common_signed_or_unsigned_type
3137 (unsigned1, TREE_TYPE (arg1)),
3138 int_fits_type_p (arg0, type)))
3140 else if (TREE_CODE (arg1) == INTEGER_CST
3141 && (unsigned0 || !uns)
3142 && (TYPE_PRECISION (TREE_TYPE (arg0))
3143 < TYPE_PRECISION (result_type))
3144 && (type = c_common_signed_or_unsigned_type
3145 (unsigned0, TREE_TYPE (arg0)),
3146 int_fits_type_p (arg1, type)))
3150 /* Shifts can be shortened if shifting right. */
3155 tree arg0 = get_narrower (op0, &unsigned_arg);
3157 final_type = result_type;
3159 if (arg0 == op0 && final_type == TREE_TYPE (op0))
3160 unsigned_arg = TREE_UNSIGNED (TREE_TYPE (op0));
3162 if (TYPE_PRECISION (TREE_TYPE (arg0)) < TYPE_PRECISION (result_type)
3163 /* We can shorten only if the shift count is less than the
3164 number of bits in the smaller type size. */
3165 && compare_tree_int (op1, TYPE_PRECISION (TREE_TYPE (arg0))) < 0
3166 /* If arg is sign-extended and then unsigned-shifted,
3167 we can simulate this with a signed shift in arg's type
3168 only if the extended result is at least twice as wide
3169 as the arg. Otherwise, the shift could use up all the
3170 ones made by sign-extension and bring in zeros.
3171 We can't optimize that case at all, but in most machines
3172 it never happens because available widths are 2**N. */
3173 && (!TREE_UNSIGNED (final_type)
3175 || (((unsigned) 2 * TYPE_PRECISION (TREE_TYPE (arg0)))
3176 <= TYPE_PRECISION (result_type))))
3178 /* Do an unsigned shift if the operand was zero-extended. */
3180 = c_common_signed_or_unsigned_type (unsigned_arg,
3182 /* Convert value-to-be-shifted to that type. */
3183 if (TREE_TYPE (op0) != result_type)
3184 op0 = cp_convert (result_type, op0);
3189 /* Comparison operations are shortened too but differently.
3190 They identify themselves by setting short_compare = 1. */
3194 /* Don't write &op0, etc., because that would prevent op0
3195 from being kept in a register.
3196 Instead, make copies of the our local variables and
3197 pass the copies by reference, then copy them back afterward. */
3198 tree xop0 = op0, xop1 = op1, xresult_type = result_type;
3199 enum tree_code xresultcode = resultcode;
3201 = shorten_compare (&xop0, &xop1, &xresult_type, &xresultcode);
3203 return cp_convert (boolean_type_node, val);
3204 op0 = xop0, op1 = xop1;
3206 resultcode = xresultcode;
3209 if ((short_compare || code == MIN_EXPR || code == MAX_EXPR)
3210 && warn_sign_compare
3211 /* Do not warn until the template is instantiated; we cannot
3212 bound the ranges of the arguments until that point. */
3213 && !processing_template_decl)
3215 int op0_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op0));
3216 int op1_signed = ! TREE_UNSIGNED (TREE_TYPE (orig_op1));
3218 int unsignedp0, unsignedp1;
3219 tree primop0 = get_narrower (op0, &unsignedp0);
3220 tree primop1 = get_narrower (op1, &unsignedp1);
3222 /* Check for comparison of different enum types. */
3223 if (TREE_CODE (TREE_TYPE (orig_op0)) == ENUMERAL_TYPE
3224 && TREE_CODE (TREE_TYPE (orig_op1)) == ENUMERAL_TYPE
3225 && TYPE_MAIN_VARIANT (TREE_TYPE (orig_op0))
3226 != TYPE_MAIN_VARIANT (TREE_TYPE (orig_op1)))
3228 warning ("comparison between types `%#T' and `%#T'",
3229 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1));
3232 /* Give warnings for comparisons between signed and unsigned
3233 quantities that may fail. */
3234 /* Do the checking based on the original operand trees, so that
3235 casts will be considered, but default promotions won't be. */
3237 /* Do not warn if the comparison is being done in a signed type,
3238 since the signed type will only be chosen if it can represent
3239 all the values of the unsigned type. */
3240 if (! TREE_UNSIGNED (result_type))
3242 /* Do not warn if both operands are unsigned. */
3243 else if (op0_signed == op1_signed)
3245 /* Do not warn if the signed quantity is an unsuffixed
3246 integer literal (or some static constant expression
3247 involving such literals or a conditional expression
3248 involving such literals) and it is non-negative. */
3249 else if ((op0_signed && tree_expr_nonnegative_p (orig_op0))
3250 || (op1_signed && tree_expr_nonnegative_p (orig_op1)))
3252 /* Do not warn if the comparison is an equality operation,
3253 the unsigned quantity is an integral constant and it does
3254 not use the most significant bit of result_type. */
3255 else if ((resultcode == EQ_EXPR || resultcode == NE_EXPR)
3256 && ((op0_signed && TREE_CODE (orig_op1) == INTEGER_CST
3257 && int_fits_type_p (orig_op1, c_common_signed_type
3259 || (op1_signed && TREE_CODE (orig_op0) == INTEGER_CST
3260 && int_fits_type_p (orig_op0, c_common_signed_type
3264 warning ("comparison between signed and unsigned integer expressions");
3266 /* Warn if two unsigned values are being compared in a size
3267 larger than their original size, and one (and only one) is the
3268 result of a `~' operator. This comparison will always fail.
3270 Also warn if one operand is a constant, and the constant does not
3271 have all bits set that are set in the ~ operand when it is
3274 if ((TREE_CODE (primop0) == BIT_NOT_EXPR)
3275 ^ (TREE_CODE (primop1) == BIT_NOT_EXPR))
3277 if (TREE_CODE (primop0) == BIT_NOT_EXPR)
3278 primop0 = get_narrower (TREE_OPERAND (op0, 0), &unsignedp0);
3279 if (TREE_CODE (primop1) == BIT_NOT_EXPR)
3280 primop1 = get_narrower (TREE_OPERAND (op1, 0), &unsignedp1);
3282 if (host_integerp (primop0, 0) || host_integerp (primop1, 0))
3285 HOST_WIDE_INT constant, mask;
3289 if (host_integerp (primop0, 0))
3292 unsignedp = unsignedp1;
3293 constant = tree_low_cst (primop0, 0);
3298 unsignedp = unsignedp0;
3299 constant = tree_low_cst (primop1, 0);
3302 bits = TYPE_PRECISION (TREE_TYPE (primop));
3303 if (bits < TYPE_PRECISION (result_type)
3304 && bits < HOST_BITS_PER_LONG && unsignedp)
3306 mask = (~ (HOST_WIDE_INT) 0) << bits;
3307 if ((mask & constant) != mask)
3308 warning ("comparison of promoted ~unsigned with constant");
3311 else if (unsignedp0 && unsignedp1
3312 && (TYPE_PRECISION (TREE_TYPE (primop0))
3313 < TYPE_PRECISION (result_type))
3314 && (TYPE_PRECISION (TREE_TYPE (primop1))
3315 < TYPE_PRECISION (result_type)))
3316 warning ("comparison of promoted ~unsigned with unsigned");
3321 /* At this point, RESULT_TYPE must be nonzero to avoid an error message.
3322 If CONVERTED is zero, both args will be converted to type RESULT_TYPE.
3323 Then the expression will be built.
3324 It will be given type FINAL_TYPE if that is nonzero;
3325 otherwise, it will be given type RESULT_TYPE. */
3329 error ("invalid operands of types `%T' and `%T' to binary `%O'",
3330 TREE_TYPE (orig_op0), TREE_TYPE (orig_op1), code);
3331 return error_mark_node;
3334 /* Issue warnings about peculiar, but valid, uses of NULL. */
3335 if (/* It's reasonable to use pointer values as operands of &&
3336 and ||, so NULL is no exception. */
3337 !(code == TRUTH_ANDIF_EXPR || code == TRUTH_ORIF_EXPR)
3338 && (/* If OP0 is NULL and OP1 is not a pointer, or vice versa. */
3339 (orig_op0 == null_node
3340 && TREE_CODE (TREE_TYPE (op1)) != POINTER_TYPE)
3341 /* Or vice versa. */
3342 || (orig_op1 == null_node
3343 && TREE_CODE (TREE_TYPE (op0)) != POINTER_TYPE)
3344 /* Or, both are NULL and the operation was not a comparison. */
3345 || (orig_op0 == null_node && orig_op1 == null_node
3346 && code != EQ_EXPR && code != NE_EXPR)))
3347 /* Some sort of arithmetic operation involving NULL was
3348 performed. Note that pointer-difference and pointer-addition
3349 have already been handled above, and so we don't end up here in
3351 warning ("NULL used in arithmetic");
3355 if (TREE_TYPE (op0) != result_type)
3356 op0 = cp_convert (result_type, op0);
3357 if (TREE_TYPE (op1) != result_type)
3358 op1 = cp_convert (result_type, op1);
3360 if (op0 == error_mark_node || op1 == error_mark_node)
3361 return error_mark_node;
3364 if (build_type == NULL_TREE)
3365 build_type = result_type;
3368 register tree result = build (resultcode, build_type, op0, op1);
3369 register tree folded;
3371 folded = fold (result);
3372 if (folded == result)
3373 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
3374 if (final_type != 0)
3375 return cp_convert (final_type, folded);
3380 /* Return a tree for the sum or difference (RESULTCODE says which)
3381 of pointer PTROP and integer INTOP. */
3384 cp_pointer_int_sum (enum tree_code resultcode, register tree ptrop,
3385 register tree intop)
3387 tree res_type = TREE_TYPE (ptrop);
3389 /* pointer_int_sum() uses size_in_bytes() on the TREE_TYPE(res_type)
3390 in certain circumstance (when it's valid to do so). So we need
3391 to make sure it's complete. We don't need to check here, if we
3392 can actually complete it at all, as those checks will be done in
3393 pointer_int_sum() anyway. */
3394 complete_type (TREE_TYPE (res_type));
3396 return pointer_int_sum (resultcode, ptrop, fold (intop));
3399 /* Return a tree for the difference of pointers OP0 and OP1.
3400 The resulting tree has type int. */
3403 pointer_diff (register tree op0, register tree op1, register tree ptrtype)
3405 register tree result, folded;
3406 tree restype = ptrdiff_type_node;
3407 tree target_type = TREE_TYPE (ptrtype);
3409 if (!complete_type_or_else (target_type, NULL_TREE))
3410 return error_mark_node;
3412 if (pedantic || warn_pointer_arith)
3414 if (TREE_CODE (target_type) == VOID_TYPE)
3415 pedwarn ("ISO C++ forbids using pointer of type `void *' in subtraction");
3416 if (TREE_CODE (target_type) == FUNCTION_TYPE)
3417 pedwarn ("ISO C++ forbids using pointer to a function in subtraction");
3418 if (TREE_CODE (target_type) == METHOD_TYPE)
3419 pedwarn ("ISO C++ forbids using pointer to a method in subtraction");
3422 /* First do the subtraction as integers;
3423 then drop through to build the divide operator. */
3425 op0 = cp_build_binary_op (MINUS_EXPR,
3426 cp_convert (restype, op0),
3427 cp_convert (restype, op1));
3429 /* This generates an error if op1 is a pointer to an incomplete type. */
3430 if (!COMPLETE_TYPE_P (TREE_TYPE (TREE_TYPE (op1))))
3431 error ("invalid use of a pointer to an incomplete type in pointer arithmetic");
3433 op1 = (TYPE_PTROB_P (ptrtype)
3434 ? size_in_bytes (target_type)
3435 : integer_one_node);
3437 /* Do the division. */
3439 result = build (EXACT_DIV_EXPR, restype, op0, cp_convert (restype, op1));
3441 folded = fold (result);
3442 if (folded == result)
3443 TREE_CONSTANT (folded) = TREE_CONSTANT (op0) & TREE_CONSTANT (op1);
3447 /* Construct and perhaps optimize a tree representation
3448 for a unary operation. CODE, a tree_code, specifies the operation
3449 and XARG is the operand. */
3452 build_x_unary_op (enum tree_code code, tree xarg)
3454 tree orig_expr = xarg;
3458 if (processing_template_decl)
3460 if (type_dependent_expression_p (xarg))
3461 return build_min_nt (code, xarg, NULL_TREE);
3462 xarg = build_non_dependent_expr (xarg);
3467 /* & rec, on incomplete RECORD_TYPEs is the simple opr &, not an
3469 if (code == ADDR_EXPR
3470 && TREE_CODE (xarg) != TEMPLATE_ID_EXPR
3471 && ((IS_AGGR_TYPE_CODE (TREE_CODE (TREE_TYPE (xarg)))
3472 && !COMPLETE_TYPE_P (TREE_TYPE (xarg)))
3473 || (TREE_CODE (xarg) == OFFSET_REF)))
3474 /* don't look for a function */;
3476 exp = build_new_op (code, LOOKUP_NORMAL, xarg, NULL_TREE, NULL_TREE);
3477 if (!exp && code == ADDR_EXPR)
3479 /* A pointer to member-function can be formed only by saying
3481 if (!flag_ms_extensions && TREE_CODE (TREE_TYPE (xarg)) == METHOD_TYPE
3482 && (TREE_CODE (xarg) != OFFSET_REF || !PTRMEM_OK_P (xarg)))
3484 if (TREE_CODE (xarg) != OFFSET_REF)
3486 error ("invalid use of '%E' to form a pointer-to-member-function. Use a qualified-id.",
3488 return error_mark_node;
3492 error ("parenthesis around '%E' cannot be used to form a pointer-to-member-function",
3494 PTRMEM_OK_P (xarg) = 1;
3498 if (TREE_CODE (xarg) == OFFSET_REF)
3500 ptrmem = PTRMEM_OK_P (xarg);
3502 if (!ptrmem && !flag_ms_extensions
3503 && TREE_CODE (TREE_TYPE (TREE_OPERAND (xarg, 1))) == METHOD_TYPE)
3505 /* A single non-static member, make sure we don't allow a
3506 pointer-to-member. */
3507 xarg = build (OFFSET_REF, TREE_TYPE (xarg),
3508 TREE_OPERAND (xarg, 0),
3509 ovl_cons (TREE_OPERAND (xarg, 1), NULL_TREE));
3510 PTRMEM_OK_P (xarg) = ptrmem;
3513 else if (TREE_CODE (xarg) == TARGET_EXPR)
3514 warning ("taking address of temporary");
3515 exp = build_unary_op (ADDR_EXPR, xarg, 0);
3516 if (TREE_CODE (exp) == ADDR_EXPR)
3517 PTRMEM_OK_P (exp) = ptrmem;
3520 if (processing_template_decl && exp != error_mark_node)
3521 return build_min (code, TREE_TYPE (exp), orig_expr, NULL_TREE);
3525 /* Like c_common_truthvalue_conversion, but handle pointer-to-member
3526 constants, where a null value is represented by an INTEGER_CST of
3530 cp_truthvalue_conversion (tree expr)
3532 tree type = TREE_TYPE (expr);
3533 if (TYPE_PTRMEM_P (type))
3534 return build_binary_op (NE_EXPR, expr, integer_zero_node, 1);
3536 return c_common_truthvalue_conversion (expr);
3539 /* Just like cp_truthvalue_conversion, but we want a CLEANUP_POINT_EXPR. */
3542 condition_conversion (tree expr)
3545 if (processing_template_decl)
3547 t = perform_implicit_conversion (boolean_type_node, expr);
3548 t = fold (build1 (CLEANUP_POINT_EXPR, boolean_type_node, t));
3552 /* Return an ADDR_EXPR giving the address of T. This function
3553 attempts no optimizations or simplifications; it is a low-level
3557 build_address (tree t)
3561 if (error_operand_p (t) || !cxx_mark_addressable (t))
3562 return error_mark_node;
3564 addr = build1 (ADDR_EXPR,
3565 build_pointer_type (TREE_TYPE (t)),
3568 TREE_CONSTANT (addr) = 1;
3573 /* Return a NOP_EXPR converting EXPR to TYPE. */
3576 build_nop (tree type, tree expr)
3580 if (type == error_mark_node || error_operand_p (expr))
3583 nop = build1 (NOP_EXPR, type, expr);
3584 if (TREE_CONSTANT (expr))
3585 TREE_CONSTANT (nop) = 1;
3590 /* C++: Must handle pointers to members.
3592 Perhaps type instantiation should be extended to handle conversion
3593 from aggregates to types we don't yet know we want? (Or are those
3594 cases typically errors which should be reported?)
3596 NOCONVERT nonzero suppresses the default promotions
3597 (such as from short to int). */
3600 build_unary_op (enum tree_code code, tree xarg, int noconvert)
3602 /* No default_conversion here. It causes trouble for ADDR_EXPR. */
3603 register tree arg = xarg;
3604 register tree argtype = 0;
3605 const char *errstring = NULL;
3608 if (arg == error_mark_node)
3609 return error_mark_node;
3614 /* This is used for unary plus, because a CONVERT_EXPR
3615 is enough to prevent anybody from looking inside for
3616 associativity, but won't generate any code. */
3617 if (!(arg = build_expr_type_conversion
3618 (WANT_ARITH | WANT_ENUM | WANT_POINTER, arg, true)))
3619 errstring = "wrong type argument to unary plus";
3623 arg = default_conversion (arg);
3624 arg = build1 (NON_LVALUE_EXPR, TREE_TYPE (arg), arg);
3625 TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
3630 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3631 errstring = "wrong type argument to unary minus";
3632 else if (!noconvert && CP_INTEGRAL_TYPE_P (TREE_TYPE (arg)))
3633 arg = perform_integral_promotions (arg);
3637 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3641 arg = default_conversion (arg);
3643 else if (!(arg = build_expr_type_conversion (WANT_INT | WANT_ENUM,
3645 errstring = "wrong type argument to bit-complement";
3646 else if (!noconvert)
3647 arg = perform_integral_promotions (arg);
3651 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3652 errstring = "wrong type argument to abs";
3653 else if (!noconvert)
3654 arg = default_conversion (arg);
3658 /* Conjugating a real value is a no-op, but allow it anyway. */
3659 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_ENUM, arg, true)))
3660 errstring = "wrong type argument to conjugation";
3661 else if (!noconvert)
3662 arg = default_conversion (arg);
3665 case TRUTH_NOT_EXPR:
3666 arg = perform_implicit_conversion (boolean_type_node, arg);
3667 val = invert_truthvalue (arg);
3668 if (arg != error_mark_node)
3670 errstring = "in argument to unary !";
3677 if (TREE_CODE (arg) == COMPLEX_CST)
3678 return TREE_REALPART (arg);
3679 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3680 return fold (build1 (REALPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
3685 if (TREE_CODE (arg) == COMPLEX_CST)
3686 return TREE_IMAGPART (arg);
3687 else if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3688 return fold (build1 (IMAGPART_EXPR, TREE_TYPE (TREE_TYPE (arg)), arg));
3690 return cp_convert (TREE_TYPE (arg), integer_zero_node);
3692 case PREINCREMENT_EXPR:
3693 case POSTINCREMENT_EXPR:
3694 case PREDECREMENT_EXPR:
3695 case POSTDECREMENT_EXPR:
3696 /* Handle complex lvalues (when permitted)
3697 by reduction to simpler cases. */
3699 val = unary_complex_lvalue (code, arg);
3703 /* Increment or decrement the real part of the value,
3704 and don't change the imaginary part. */
3705 if (TREE_CODE (TREE_TYPE (arg)) == COMPLEX_TYPE)
3709 arg = stabilize_reference (arg);
3710 real = build_unary_op (REALPART_EXPR, arg, 1);
3711 imag = build_unary_op (IMAGPART_EXPR, arg, 1);
3712 return build (COMPLEX_EXPR, TREE_TYPE (arg),
3713 build_unary_op (code, real, 1), imag);
3716 /* Report invalid types. */
3718 if (!(arg = build_expr_type_conversion (WANT_ARITH | WANT_POINTER,
3721 if (code == PREINCREMENT_EXPR)
3722 errstring ="no pre-increment operator for type";
3723 else if (code == POSTINCREMENT_EXPR)
3724 errstring ="no post-increment operator for type";
3725 else if (code == PREDECREMENT_EXPR)
3726 errstring ="no pre-decrement operator for type";
3728 errstring ="no post-decrement operator for type";
3732 /* Report something read-only. */
3734 if (CP_TYPE_CONST_P (TREE_TYPE (arg))
3735 || TREE_READONLY (arg))
3736 readonly_error (arg, ((code == PREINCREMENT_EXPR
3737 || code == POSTINCREMENT_EXPR)
3738 ? "increment" : "decrement"),
3743 tree result_type = TREE_TYPE (arg);
3745 arg = get_unwidened (arg, 0);
3746 argtype = TREE_TYPE (arg);
3748 /* ARM $5.2.5 last annotation says this should be forbidden. */
3749 if (TREE_CODE (argtype) == ENUMERAL_TYPE)
3750 pedwarn ("ISO C++ forbids %sing an enum",
3751 (code == PREINCREMENT_EXPR || code == POSTINCREMENT_EXPR)
3752 ? "increment" : "decrement");
3754 /* Compute the increment. */
3756 if (TREE_CODE (argtype) == POINTER_TYPE)
3758 tree type = complete_type (TREE_TYPE (argtype));
3760 if (!COMPLETE_OR_VOID_TYPE_P (type))
3761 error ("cannot %s a pointer to incomplete type `%T'",
3762 ((code == PREINCREMENT_EXPR
3763 || code == POSTINCREMENT_EXPR)
3764 ? "increment" : "decrement"), TREE_TYPE (argtype));
3765 else if ((pedantic || warn_pointer_arith)
3766 && !TYPE_PTROB_P (argtype))
3767 pedwarn ("ISO C++ forbids %sing a pointer of type `%T'",
3768 ((code == PREINCREMENT_EXPR
3769 || code == POSTINCREMENT_EXPR)
3770 ? "increment" : "decrement"), argtype);
3771 inc = cxx_sizeof_nowarn (TREE_TYPE (argtype));
3774 inc = integer_one_node;
3776 inc = cp_convert (argtype, inc);
3778 /* Handle incrementing a cast-expression. */
3780 switch (TREE_CODE (arg))
3785 case FIX_TRUNC_EXPR:
3786 case FIX_FLOOR_EXPR:
3787 case FIX_ROUND_EXPR:
3790 tree incremented, modify, value, compound;
3791 if (! lvalue_p (arg) && pedantic)
3792 pedwarn ("cast to non-reference type used as lvalue");
3793 arg = stabilize_reference (arg);
3794 if (code == PREINCREMENT_EXPR || code == PREDECREMENT_EXPR)
3797 value = save_expr (arg);
3798 incremented = build (((code == PREINCREMENT_EXPR
3799 || code == POSTINCREMENT_EXPR)
3800 ? PLUS_EXPR : MINUS_EXPR),
3801 argtype, value, inc);
3803 modify = build_modify_expr (arg, NOP_EXPR, incremented);
3804 compound = build (COMPOUND_EXPR, TREE_TYPE (arg), modify, value);
3806 /* Eliminate warning about unused result of + or -. */
3807 TREE_NO_UNUSED_WARNING (compound) = 1;
3815 /* Complain about anything else that is not a true lvalue. */
3816 if (!lvalue_or_else (arg, ((code == PREINCREMENT_EXPR
3817 || code == POSTINCREMENT_EXPR)
3818 ? "increment" : "decrement")))
3819 return error_mark_node;
3821 /* Forbid using -- on `bool'. */
3822 if (TREE_TYPE (arg) == boolean_type_node)
3824 if (code == POSTDECREMENT_EXPR || code == PREDECREMENT_EXPR)
3826 error ("invalid use of `--' on bool variable `%D'", arg);
3827 return error_mark_node;
3829 val = boolean_increment (code, arg);
3832 val = build (code, TREE_TYPE (arg), arg, inc);
3834 TREE_SIDE_EFFECTS (val) = 1;
3835 return cp_convert (result_type, val);
3839 /* Note that this operation never does default_conversion
3840 regardless of NOCONVERT. */
3842 argtype = lvalue_type (arg);
3844 if (TREE_CODE (arg) == OFFSET_REF)
3847 if (TREE_CODE (argtype) == REFERENCE_TYPE)
3851 build_pointer_type (TREE_TYPE (argtype)), arg);
3852 TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
3855 else if (pedantic && DECL_MAIN_P (arg))
3857 pedwarn ("ISO C++ forbids taking address of function `::main'");
3859 /* Let &* cancel out to simplify resulting code. */
3860 if (TREE_CODE (arg) == INDIRECT_REF)
3862 /* We don't need to have `current_class_ptr' wrapped in a
3863 NON_LVALUE_EXPR node. */
3864 if (arg == current_class_ref)
3865 return current_class_ptr;
3867 arg = TREE_OPERAND (arg, 0);
3868 if (TREE_CODE (TREE_TYPE (arg)) == REFERENCE_TYPE)
3872 build_pointer_type (TREE_TYPE (TREE_TYPE (arg))), arg);
3873 TREE_CONSTANT (arg) = TREE_CONSTANT (TREE_OPERAND (arg, 0));
3875 else if (lvalue_p (arg))
3876 /* Don't let this be an lvalue. */
3877 return non_lvalue (arg);
3881 /* For &x[y], return x+y */
3882 if (TREE_CODE (arg) == ARRAY_REF)
3884 if (!cxx_mark_addressable (TREE_OPERAND (arg, 0)))
3885 return error_mark_node;
3886 return cp_build_binary_op (PLUS_EXPR, TREE_OPERAND (arg, 0),
3887 TREE_OPERAND (arg, 1));
3890 /* Uninstantiated types are all functions. Taking the
3891 address of a function is a no-op, so just return the
3894 if (TREE_CODE (arg) == IDENTIFIER_NODE
3895 && IDENTIFIER_OPNAME_P (arg))
3898 /* We don't know the type yet, so just work around the problem.
3899 We know that this will resolve to an lvalue. */
3900 return build1 (ADDR_EXPR, unknown_type_node, arg);
3903 if (TREE_CODE (arg) == COMPONENT_REF && type_unknown_p (arg)
3904 && !really_overloaded_fn (TREE_OPERAND (arg, 1)))
3906 /* They're trying to take the address of a unique non-static
3907 member function. This is ill-formed (except in MS-land),
3908 but let's try to DTRT.
3909 Note: We only handle unique functions here because we don't
3910 want to complain if there's a static overload; non-unique
3911 cases will be handled by instantiate_type. But we need to
3912 handle this case here to allow casts on the resulting PMF.
3913 We could defer this in non-MS mode, but it's easier to give
3914 a useful error here. */
3916 /* Inside constant member functions, the `this' pointer
3917 contains an extra const qualifier. TYPE_MAIN_VARIANT
3918 is used here to remove this const from the diagnostics
3919 and the created OFFSET_REF. */
3920 tree base = TYPE_MAIN_VARIANT (TREE_TYPE (TREE_OPERAND (arg, 0)));
3921 tree name = DECL_NAME (get_first_fn (TREE_OPERAND (arg, 1)));
3923 if (! flag_ms_extensions)
3925 if (current_class_type
3926 && TREE_OPERAND (arg, 0) == current_class_ref)
3927 /* An expression like &memfn. */
3928 pedwarn ("ISO C++ forbids taking the address of an unqualified"
3929 " or parenthesized non-static member function to form"
3930 " a pointer to member function. Say `&%T::%D'",
3933 pedwarn ("ISO C++ forbids taking the address of a bound member"
3934 " function to form a pointer to member function."
3938 arg = build_offset_ref (base, name, /*address_p=*/true);
3942 if (type_unknown_p (arg))
3943 return build1 (ADDR_EXPR, unknown_type_node, arg);
3945 /* Handle complex lvalues (when permitted)
3946 by reduction to simpler cases. */
3947 val = unary_complex_lvalue (code, arg);
3951 switch (TREE_CODE (arg))
3956 case FIX_TRUNC_EXPR:
3957 case FIX_FLOOR_EXPR:
3958 case FIX_ROUND_EXPR:
3960 if (! lvalue_p (arg) && pedantic)
3961 pedwarn ("ISO C++ forbids taking the address of a cast to a non-lvalue expression");
3968 /* Allow the address of a constructor if all the elements
3970 if (TREE_CODE (arg) == CONSTRUCTOR && TREE_HAS_CONSTRUCTOR (arg)
3971 && TREE_CONSTANT (arg))
3973 /* Anything not already handled and not a true memory reference
3975 else if (TREE_CODE (argtype) != FUNCTION_TYPE
3976 && TREE_CODE (argtype) != METHOD_TYPE
3977 && !non_cast_lvalue_or_else (arg, "unary `&'"))
3978 return error_mark_node;
3980 if (argtype != error_mark_node)
3981 argtype = build_pointer_type (argtype);
3986 if (TREE_CODE (arg) == COMPONENT_REF
3987 && TREE_CODE (TREE_OPERAND (arg, 1)) == BASELINK)
3988 arg = BASELINK_FUNCTIONS (TREE_OPERAND (arg, 1));
3990 if (TREE_CODE (arg) != COMPONENT_REF)
3991 addr = build_address (arg);
3992 else if (DECL_C_BIT_FIELD (TREE_OPERAND (arg, 1)))
3994 error ("attempt to take address of bit-field structure member `%D'",
3995 TREE_OPERAND (arg, 1));
3996 return error_mark_node;
4000 /* Unfortunately we cannot just build an address
4001 expression here, because we would not handle
4002 address-constant-expressions or offsetof correctly. */
4003 tree field = TREE_OPERAND (arg, 1);
4004 tree rval = build_unary_op (ADDR_EXPR, TREE_OPERAND (arg, 0), 0);
4005 tree binfo = lookup_base (TREE_TYPE (TREE_TYPE (rval)),
4006 decl_type_context (field),
4009 rval = build_base_path (PLUS_EXPR, rval, binfo, 1);
4010 rval = build1 (NOP_EXPR, argtype, rval);
4011 TREE_CONSTANT (rval) = TREE_CONSTANT (TREE_OPERAND (rval, 0));
4012 addr = fold (build (PLUS_EXPR, argtype, rval,
4013 cp_convert (argtype, byte_position (field))));
4016 if (TREE_CODE (argtype) == POINTER_TYPE
4017 && TREE_CODE (TREE_TYPE (argtype)) == METHOD_TYPE)
4019 build_ptrmemfunc_type (argtype);
4020 addr = build_ptrmemfunc (argtype, addr, 0);
4033 argtype = TREE_TYPE (arg);
4034 return fold (build1 (code, argtype, arg));
4037 error ("%s", errstring);
4038 return error_mark_node;
4041 /* Apply unary lvalue-demanding operator CODE to the expression ARG
4042 for certain kinds of expressions which are not really lvalues
4043 but which we can accept as lvalues.
4045 If ARG is not a kind of expression we can handle, return zero. */
4048 unary_complex_lvalue (enum tree_code code, tree arg)
4050 /* Handle (a, b) used as an "lvalue". */
4051 if (TREE_CODE (arg) == COMPOUND_EXPR)
4053 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 1), 0);
4054 return build (COMPOUND_EXPR, TREE_TYPE (real_result),
4055 TREE_OPERAND (arg, 0), real_result);
4058 /* Handle (a ? b : c) used as an "lvalue". */
4059 if (TREE_CODE (arg) == COND_EXPR
4060 || TREE_CODE (arg) == MIN_EXPR || TREE_CODE (arg) == MAX_EXPR)
4061 return rationalize_conditional_expr (code, arg);
4063 /* Handle (a = b), (++a), and (--a) used as an "lvalue". */
4064 if (TREE_CODE (arg) == MODIFY_EXPR
4065 || TREE_CODE (arg) == PREINCREMENT_EXPR
4066 || TREE_CODE (arg) == PREDECREMENT_EXPR)
4068 tree lvalue = TREE_OPERAND (arg, 0);
4069 if (TREE_SIDE_EFFECTS (lvalue))
4071 lvalue = stabilize_reference (lvalue);
4072 arg = build (TREE_CODE (arg), TREE_TYPE (arg),
4073 lvalue, TREE_OPERAND (arg, 1));
4075 return unary_complex_lvalue
4076 (code, build (COMPOUND_EXPR, TREE_TYPE (lvalue), arg, lvalue));
4079 if (code != ADDR_EXPR)
4082 /* Handle (a = b) used as an "lvalue" for `&'. */
4083 if (TREE_CODE (arg) == MODIFY_EXPR
4084 || TREE_CODE (arg) == INIT_EXPR)
4086 tree real_result = build_unary_op (code, TREE_OPERAND (arg, 0), 0);
4087 arg = build (COMPOUND_EXPR, TREE_TYPE (real_result), arg, real_result);
4088 TREE_NO_UNUSED_WARNING (arg) = 1;
4092 if (TREE_CODE (TREE_TYPE (arg)) == FUNCTION_TYPE
4093 || TREE_CODE (TREE_TYPE (arg)) == METHOD_TYPE
4094 || TREE_CODE (arg) == OFFSET_REF)
4098 my_friendly_assert (TREE_CODE (arg) != SCOPE_REF, 313);
4100 if (TREE_CODE (arg) != OFFSET_REF)
4103 t = TREE_OPERAND (arg, 1);
4105 /* Check all this code for right semantics. */
4106 if (TREE_CODE (t) == FUNCTION_DECL)
4108 if (DECL_DESTRUCTOR_P (t))
4109 error ("taking address of destructor");
4110 return build_unary_op (ADDR_EXPR, t, 0);
4112 if (TREE_CODE (t) == VAR_DECL)
4113 return build_unary_op (ADDR_EXPR, t, 0);
4118 if (TREE_OPERAND (arg, 0)
4119 && ! is_dummy_object (TREE_OPERAND (arg, 0))
4120 && TREE_CODE (t) != FIELD_DECL)
4122 error ("taking address of bound pointer-to-member expression");
4123 return error_mark_node;
4125 if (!PTRMEM_OK_P (arg))
4126 return build_unary_op (code, arg, 0);
4128 if (TREE_CODE (TREE_TYPE (t)) == REFERENCE_TYPE)
4130 error ("cannot create pointer to reference member `%D'", t);
4131 return error_mark_node;
4134 type = build_ptrmem_type (DECL_FIELD_CONTEXT (t), TREE_TYPE (t));
4135 t = make_ptrmem_cst (type, TREE_OPERAND (arg, 1));
4141 /* We permit compiler to make function calls returning
4142 objects of aggregate type look like lvalues. */
4146 if (TREE_CODE (targ) == SAVE_EXPR)
4147 targ = TREE_OPERAND (targ, 0);
4149 if (TREE_CODE (targ) == CALL_EXPR && IS_AGGR_TYPE (TREE_TYPE (targ)))
4151 if (TREE_CODE (arg) == SAVE_EXPR)
4154 targ = build_cplus_new (TREE_TYPE (arg), arg);
4155 return build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (arg)), targ);
4158 if (TREE_CODE (arg) == SAVE_EXPR && TREE_CODE (targ) == INDIRECT_REF)
4159 return build (SAVE_EXPR, build_pointer_type (TREE_TYPE (arg)),
4160 TREE_OPERAND (targ, 0), current_function_decl, NULL);
4163 /* Don't let anything else be handled specially. */
4167 /* Mark EXP saying that we need to be able to take the
4168 address of it; it should not be allocated in a register.
4169 Value is true if successful.
4171 C++: we do not allow `current_class_ptr' to be addressable. */
4174 cxx_mark_addressable (tree exp)
4176 register tree x = exp;
4179 switch (TREE_CODE (x))
4186 x = TREE_OPERAND (x, 0);
4190 if (x == current_class_ptr)
4192 error ("cannot take the address of `this', which is an rvalue expression");
4193 TREE_ADDRESSABLE (x) = 1; /* so compiler doesn't die later */
4199 /* Caller should not be trying to mark initialized
4200 constant fields addressable. */
4201 my_friendly_assert (DECL_LANG_SPECIFIC (x) == 0
4202 || DECL_IN_AGGR_P (x) == 0
4204 || DECL_EXTERNAL (x), 314);
4209 if (DECL_REGISTER (x) && !TREE_ADDRESSABLE (x)
4210 && !DECL_ARTIFICIAL (x) && extra_warnings)
4211 warning ("address requested for `%D', which is declared `register'",
4213 TREE_ADDRESSABLE (x) = 1;
4214 put_var_into_stack (x, /*rescan=*/true);
4218 TREE_ADDRESSABLE (x) = 1;
4219 TREE_ADDRESSABLE (DECL_ASSEMBLER_NAME (x)) = 1;
4223 TREE_ADDRESSABLE (x) = 1;
4227 TREE_ADDRESSABLE (x) = 1;
4228 cxx_mark_addressable (TREE_OPERAND (x, 0));
4236 /* Build and return a conditional expression IFEXP ? OP1 : OP2. */
4239 build_x_conditional_expr (tree ifexp, tree op1, tree op2)
4241 tree orig_ifexp = ifexp;
4242 tree orig_op1 = op1;
4243 tree orig_op2 = op2;
4246 if (processing_template_decl)
4248 /* The standard says that the expression is type-dependent if
4249 IFEXP is type-dependent, even though the eventual type of the
4250 expression doesn't dependent on IFEXP. */
4251 if (type_dependent_expression_p (ifexp)
4252 || type_dependent_expression_p (op1)
4253 || type_dependent_expression_p (op2))
4254 return build_min_nt (COND_EXPR, ifexp, op1, op2);
4255 ifexp = build_non_dependent_expr (ifexp);
4256 op1 = build_non_dependent_expr (op1);
4257 op2 = build_non_dependent_expr (op2);
4260 expr = build_conditional_expr (ifexp, op1, op2);
4261 if (processing_template_decl && expr != error_mark_node)
4262 return build_min (COND_EXPR, TREE_TYPE (expr),
4263 orig_ifexp, orig_op1, orig_op2);
4267 /* Given a list of expressions, return a compound expression
4268 that performs them all and returns the value of the last of them. */
4270 tree build_x_compound_expr_from_list (tree list, const char *msg)
4272 tree expr = TREE_VALUE (list);
4274 if (TREE_CHAIN (list))
4277 pedwarn ("%s expression list treated as compound expression", msg);
4279 for (list = TREE_CHAIN (list); list; list = TREE_CHAIN (list))
4280 expr = build_x_compound_expr (expr, TREE_VALUE (list));
4286 /* Handle overloading of the ',' operator when needed. */
4289 build_x_compound_expr (tree op1, tree op2)
4292 tree orig_op1 = op1;
4293 tree orig_op2 = op2;
4295 if (processing_template_decl)
4297 if (type_dependent_expression_p (op1)
4298 || type_dependent_expression_p (op2))
4299 return build_min_nt (COMPOUND_EXPR, op1, op2);
4300 op1 = build_non_dependent_expr (op1);
4301 op2 = build_non_dependent_expr (op2);
4304 result = build_new_op (COMPOUND_EXPR, LOOKUP_NORMAL, op1, op2, NULL_TREE);
4307 if (! TREE_SIDE_EFFECTS (op1))
4309 /* FIXME: This test should be in the implicit cast to void
4311 /* the left-hand operand of a comma expression is like an expression
4312 statement: we should warn if it doesn't have any side-effects,
4313 unless it was explicitly cast to (void). */
4314 if (warn_unused_value
4315 && !(TREE_CODE (op1) == CONVERT_EXPR
4316 && VOID_TYPE_P (TREE_TYPE (op1))))
4317 warning("left-hand operand of comma expression has no effect");
4319 result = build_compound_expr (op1, op2);
4322 if (processing_template_decl && result != error_mark_node)
4323 return build_min (COMPOUND_EXPR, TREE_TYPE (result),
4324 orig_op1, orig_op2);
4328 /* Build a compound expression. */
4331 build_compound_expr (tree lhs, tree rhs)
4333 lhs = decl_constant_value (lhs);
4334 lhs = convert_to_void (lhs, "left-hand operand of comma");
4335 if (lhs == error_mark_node || rhs == error_mark_node)
4336 return error_mark_node;
4338 return build (COMPOUND_EXPR, TREE_TYPE (rhs), lhs, rhs);
4341 /* Issue an error message if casting from SRC_TYPE to DEST_TYPE casts
4342 away constness. DESCRIPTION explains what operation is taking
4346 check_for_casting_away_constness (tree src_type, tree dest_type,
4347 const char *description)
4349 if (casts_away_constness (src_type, dest_type))
4350 error ("%s from type `%T' to type `%T' casts away constness",
4351 description, src_type, dest_type);
4354 /* Return an expression representing static_cast<TYPE>(EXPR). */
4357 build_static_cast (tree type, tree expr)
4362 if (type == error_mark_node || expr == error_mark_node)
4363 return error_mark_node;
4365 if (processing_template_decl)
4367 tree t = build_min (STATIC_CAST_EXPR, type, expr);
4371 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4372 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4373 if (TREE_CODE (type) != REFERENCE_TYPE
4374 && TREE_CODE (expr) == NOP_EXPR
4375 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4376 expr = TREE_OPERAND (expr, 0);
4378 intype = TREE_TYPE (expr);
4380 /* [expr.static.cast]
4382 An lvalue of type "cv1 B", where B is a class type, can be cast
4383 to type "reference to cv2 D", where D is a class derived (clause
4384 _class.derived_) from B, if a valid standard conversion from
4385 "pointer to D" to "pointer to B" exists (_conv.ptr_), cv2 is the
4386 same cv-qualification as, or greater cv-qualification than, cv1,
4387 and B is not a virtual base class of D. */
4388 /* We check this case before checking the validity of "TYPE t =
4389 EXPR;" below because for this case:
4392 struct D : public B { D(const B&); };
4394 void f() { static_cast<const D&>(b); }
4396 we want to avoid constructing a new D. The standard is not
4397 completely clear about this issue, but our interpretation is
4398 consistent with other compilers. */
4399 if (TREE_CODE (type) == REFERENCE_TYPE
4400 && CLASS_TYPE_P (TREE_TYPE (type))
4401 && CLASS_TYPE_P (intype)
4402 && real_non_cast_lvalue_p (expr)
4403 && DERIVED_FROM_P (intype, TREE_TYPE (type))
4404 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT (intype)),
4405 build_pointer_type (TYPE_MAIN_VARIANT
4406 (TREE_TYPE (type))))
4407 && at_least_as_qualified_p (TREE_TYPE (type), intype))
4409 /* At this point we have checked all of the conditions except
4410 that B is not a virtual base class of D. That will be
4411 checked by build_base_path. */
4412 tree base = lookup_base (TREE_TYPE (type), intype, ba_any, NULL);
4414 /* Convert from B* to D*. */
4415 expr = build_base_path (MINUS_EXPR, build_address (expr),
4416 base, /*nonnull=*/false);
4417 /* Convert the pointer to a reference -- but then remember that
4418 there are no expressions with reference type in C++. */
4419 return convert_from_reference (build_nop (type, expr));
4422 /* [expr.static.cast]
4424 An expression e can be explicitly converted to a type T using a
4425 static_cast of the form static_cast<T>(e) if the declaration T
4426 t(e);" is well-formed, for some invented temporary variable
4428 result = perform_direct_initialization_if_possible (type, expr);
4430 return convert_from_reference (result);
4432 /* [expr.static.cast]
4434 Any expression can be explicitly converted to type cv void. */
4435 if (TREE_CODE (type) == VOID_TYPE)
4436 return convert_to_void (expr, /*implicit=*/NULL);
4438 /* [expr.static.cast]
4440 The inverse of any standard conversion sequence (clause _conv_),
4441 other than the lvalue-to-rvalue (_conv.lval_), array-to-pointer
4442 (_conv.array_), function-to-pointer (_conv.func_), and boolean
4443 (_conv.bool_) conversions, can be performed explicitly using
4444 static_cast subject to the restriction that the explicit
4445 conversion does not cast away constness (_expr.const.cast_), and
4446 the following additional rules for specific cases: */
4447 /* For reference, the conversions not excluded are: integral
4448 promotions, floating point promotion, integral conversions,
4449 floating point conversions, floating-integral conversions,
4450 pointer conversions, and pointer to member conversions. */
4451 if ((ARITHMETIC_TYPE_P (type) && ARITHMETIC_TYPE_P (intype))
4454 A value of integral _or enumeration_ type can be explicitly
4455 converted to an enumeration type. */
4456 || (INTEGRAL_OR_ENUMERATION_TYPE_P (type)
4457 && INTEGRAL_OR_ENUMERATION_TYPE_P (intype)))
4458 /* Really, build_c_cast should defer to this function rather
4459 than the other way around. */
4460 return build_c_cast (type, expr);
4461 if (TYPE_PTR_P (type) && TYPE_PTR_P (intype)
4462 && CLASS_TYPE_P (TREE_TYPE (type))
4463 && CLASS_TYPE_P (TREE_TYPE (intype))
4464 && can_convert (build_pointer_type (TYPE_MAIN_VARIANT
4465 (TREE_TYPE (intype))),
4466 build_pointer_type (TYPE_MAIN_VARIANT
4467 (TREE_TYPE (type)))))
4471 check_for_casting_away_constness (intype, type, "static_cast");
4472 base = lookup_base (TREE_TYPE (type), TREE_TYPE (intype),
4473 ba_check | ba_quiet, NULL);
4474 return build_base_path (MINUS_EXPR, expr, base, /*nonnull=*/false);
4476 if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4477 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4484 c1 = TYPE_PTRMEM_CLASS_TYPE (intype);
4485 c2 = TYPE_PTRMEM_CLASS_TYPE (type);
4487 if (TYPE_PTRMEM_P (type))
4489 t1 = (build_ptrmem_type
4491 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (intype))));
4492 t2 = (build_ptrmem_type
4494 TYPE_MAIN_VARIANT (TYPE_PTRMEM_POINTED_TO_TYPE (type))));
4501 if (can_convert (t1, t2))
4503 check_for_casting_away_constness (intype, type, "static_cast");
4504 if (TYPE_PTRMEM_P (type))
4508 if (TREE_CODE (expr) == PTRMEM_CST)
4509 expr = cplus_expand_constant (expr);
4510 delta = get_delta_difference (c1, c2, /*force=*/1);
4511 if (!integer_zerop (delta))
4512 expr = cp_build_binary_op (PLUS_EXPR,
4513 build_nop (ptrdiff_type_node, expr),
4515 return build_nop (type, expr);
4518 return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr,
4523 /* [expr.static.cast]
4525 An rvalue of type "pointer to cv void" can be explicitly
4526 converted to a pointer to object type. A value of type pointer
4527 to object converted to "pointer to cv void" and back to the
4528 original pointer type will have its original value. */
4529 if (TREE_CODE (intype) == POINTER_TYPE
4530 && VOID_TYPE_P (TREE_TYPE (intype))
4531 && TYPE_PTROB_P (type))
4533 check_for_casting_away_constness (intype, type, "static_cast");
4534 return build_nop (type, expr);
4537 error ("invalid static_cast from type `%T' to type `%T'", intype, type);
4538 return error_mark_node;
4542 build_reinterpret_cast (tree type, tree expr)
4546 if (type == error_mark_node || expr == error_mark_node)
4547 return error_mark_node;
4549 if (processing_template_decl)
4551 tree t = build_min (REINTERPRET_CAST_EXPR, type, expr);
4555 if (TREE_CODE (type) != REFERENCE_TYPE)
4557 expr = decay_conversion (expr);
4559 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4560 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4561 if (TREE_CODE (expr) == NOP_EXPR
4562 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4563 expr = TREE_OPERAND (expr, 0);
4566 intype = TREE_TYPE (expr);
4568 if (TREE_CODE (type) == REFERENCE_TYPE)
4570 if (! real_lvalue_p (expr))
4572 error ("invalid reinterpret_cast of an rvalue expression of type `%T' to type `%T'", intype, type);
4573 return error_mark_node;
4575 expr = build_unary_op (ADDR_EXPR, expr, 0);
4576 if (expr != error_mark_node)
4577 expr = build_reinterpret_cast
4578 (build_pointer_type (TREE_TYPE (type)), expr);
4579 if (expr != error_mark_node)
4580 expr = build_indirect_ref (expr, 0);
4583 else if (same_type_ignoring_top_level_qualifiers_p (intype, type))
4584 return build_static_cast (type, expr);
4586 if (TYPE_PTR_P (type) && (TREE_CODE (intype) == INTEGER_TYPE
4587 || TREE_CODE (intype) == ENUMERAL_TYPE))
4589 else if (TREE_CODE (type) == INTEGER_TYPE && TYPE_PTR_P (intype))
4591 if (TYPE_PRECISION (type) < TYPE_PRECISION (intype))
4592 pedwarn ("reinterpret_cast from `%T' to `%T' loses precision",
4595 else if ((TYPE_PTRFN_P (type) && TYPE_PTRFN_P (intype))
4596 || (TYPE_PTRMEMFUNC_P (type) && TYPE_PTRMEMFUNC_P (intype)))
4598 expr = decl_constant_value (expr);
4599 return fold (build1 (NOP_EXPR, type, expr));
4601 else if ((TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype))
4602 || (TYPE_PTROBV_P (type) && TYPE_PTROBV_P (intype)))
4604 check_for_casting_away_constness (intype, type, "reinterpret_cast");
4605 expr = decl_constant_value (expr);
4606 return fold (build1 (NOP_EXPR, type, expr));
4608 else if ((TYPE_PTRFN_P (type) && TYPE_PTROBV_P (intype))
4609 || (TYPE_PTRFN_P (intype) && TYPE_PTROBV_P (type)))
4611 pedwarn ("ISO C++ forbids casting between pointer-to-function and pointer-to-object");
4612 expr = decl_constant_value (expr);
4613 return fold (build1 (NOP_EXPR, type, expr));
4617 error ("invalid reinterpret_cast from type `%T' to type `%T'",
4619 return error_mark_node;
4622 return cp_convert (type, expr);
4626 build_const_cast (tree type, tree expr)
4630 if (type == error_mark_node || expr == error_mark_node)
4631 return error_mark_node;
4633 if (processing_template_decl)
4635 tree t = build_min (CONST_CAST_EXPR, type, expr);
4639 if (!POINTER_TYPE_P (type))
4640 error ("invalid use of const_cast with type `%T', which is not a pointer, reference, nor a pointer-to-data-member type", type);
4641 else if (TREE_CODE (TREE_TYPE (type)) == FUNCTION_TYPE)
4643 error ("invalid use of const_cast with type `%T', which is a pointer or reference to a function type", type);
4644 return error_mark_node;
4647 if (TREE_CODE (type) != REFERENCE_TYPE)
4649 expr = decay_conversion (expr);
4651 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4652 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4653 if (TREE_CODE (expr) == NOP_EXPR
4654 && TREE_TYPE (expr) == TREE_TYPE (TREE_OPERAND (expr, 0)))
4655 expr = TREE_OPERAND (expr, 0);
4658 intype = TREE_TYPE (expr);
4660 if (same_type_ignoring_top_level_qualifiers_p (intype, type))
4661 return build_static_cast (type, expr);
4662 else if (TREE_CODE (type) == REFERENCE_TYPE)
4664 if (! real_lvalue_p (expr))
4666 error ("invalid const_cast of an rvalue of type `%T' to type `%T'", intype, type);
4667 return error_mark_node;
4670 if (comp_ptr_ttypes_const (TREE_TYPE (type), intype))
4672 expr = build_unary_op (ADDR_EXPR, expr, 0);
4673 expr = build1 (NOP_EXPR, type, expr);
4674 return convert_from_reference (expr);
4677 else if (((TREE_CODE (type) == POINTER_TYPE
4678 && TREE_CODE (intype) == POINTER_TYPE)
4679 || (TYPE_PTRMEM_P (type) && TYPE_PTRMEM_P (intype)))
4680 && comp_ptr_ttypes_const (TREE_TYPE (type), TREE_TYPE (intype)))
4681 return cp_convert (type, expr);
4683 error ("invalid const_cast from type `%T' to type `%T'", intype, type);
4684 return error_mark_node;
4687 /* Build an expression representing a cast to type TYPE of expression EXPR.
4689 ALLOW_NONCONVERTING is true if we should allow non-converting constructors
4690 when doing the cast. */
4693 build_c_cast (tree type, tree expr)
4695 register tree value = expr;
4698 if (type == error_mark_node || expr == error_mark_node)
4699 return error_mark_node;
4701 if (processing_template_decl)
4703 tree t = build_min (CAST_EXPR, type,
4704 tree_cons (NULL_TREE, value, NULL_TREE));
4708 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
4709 Strip such NOP_EXPRs if VALUE is being used in non-lvalue context. */
4710 if (TREE_CODE (type) != REFERENCE_TYPE
4711 && TREE_CODE (value) == NOP_EXPR
4712 && TREE_TYPE (value) == TREE_TYPE (TREE_OPERAND (value, 0)))
4713 value = TREE_OPERAND (value, 0);
4715 if (TREE_CODE (type) == ARRAY_TYPE)
4717 /* Allow casting from T1* to T2[] because Cfront allows it.
4718 NIHCL uses it. It is not valid ISO C++ however. */
4719 if (TREE_CODE (TREE_TYPE (expr)) == POINTER_TYPE)
4721 pedwarn ("ISO C++ forbids casting to an array type `%T'", type);
4722 type = build_pointer_type (TREE_TYPE (type));
4726 error ("ISO C++ forbids casting to an array type `%T'", type);
4727 return error_mark_node;
4731 if (TREE_CODE (type) == FUNCTION_TYPE
4732 || TREE_CODE (type) == METHOD_TYPE)
4734 error ("invalid cast to function type `%T'", type);
4735 return error_mark_node;
4738 if (TREE_CODE (type) == VOID_TYPE)
4740 /* Conversion to void does not cause any of the normal function to
4741 * pointer, array to pointer and lvalue to rvalue decays. */
4743 value = convert_to_void (value, /*implicit=*/NULL);
4747 if (!complete_type_or_else (type, NULL_TREE))
4748 return error_mark_node;
4750 /* Convert functions and arrays to pointers and
4751 convert references to their expanded types,
4752 but don't convert any other types. If, however, we are
4753 casting to a class type, there's no reason to do this: the
4754 cast will only succeed if there is a converting constructor,
4755 and the default conversions will be done at that point. In
4756 fact, doing the default conversion here is actually harmful
4760 struct S { S(const A&); };
4762 since we don't want the array-to-pointer conversion done. */
4763 if (!IS_AGGR_TYPE (type))
4765 if (TREE_CODE (TREE_TYPE (value)) == FUNCTION_TYPE
4766 || (TREE_CODE (TREE_TYPE (value)) == METHOD_TYPE
4767 /* Don't do the default conversion on a ->* expression. */
4768 && ! (TREE_CODE (type) == POINTER_TYPE
4769 && bound_pmf_p (value)))
4770 || TREE_CODE (TREE_TYPE (value)) == ARRAY_TYPE
4771 || TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
4772 value = decay_conversion (value);
4774 else if (TREE_CODE (TREE_TYPE (value)) == REFERENCE_TYPE)
4775 /* However, even for class types, we still need to strip away
4776 the reference type, since the call to convert_force below
4777 does not expect the input expression to be of reference
4779 value = convert_from_reference (value);
4781 otype = TREE_TYPE (value);
4783 /* Optionally warn about potentially worrisome casts. */
4786 && TREE_CODE (type) == POINTER_TYPE
4787 && TREE_CODE (otype) == POINTER_TYPE
4788 && !at_least_as_qualified_p (TREE_TYPE (type),
4790 warning ("cast from `%T' to `%T' discards qualifiers from pointer target type",
4793 if (TREE_CODE (type) == INTEGER_TYPE
4794 && TYPE_PTR_P (otype)
4795 && TYPE_PRECISION (type) != TYPE_PRECISION (otype))
4796 warning ("cast from pointer to integer of different size");
4798 if (TYPE_PTR_P (type)
4799 && TREE_CODE (otype) == INTEGER_TYPE
4800 && TYPE_PRECISION (type) != TYPE_PRECISION (otype)
4801 /* Don't warn about converting any constant. */
4802 && !TREE_CONSTANT (value))
4803 warning ("cast to pointer from integer of different size");
4805 if (TREE_CODE (type) == REFERENCE_TYPE)
4806 value = (convert_from_reference
4807 (convert_to_reference (type, value, CONV_C_CAST,
4808 LOOKUP_COMPLAIN, NULL_TREE)));
4813 value = decl_constant_value (value);
4816 value = convert_force (type, value, CONV_C_CAST);
4818 /* Ignore any integer overflow caused by the cast. */
4819 if (TREE_CODE (value) == INTEGER_CST)
4821 TREE_OVERFLOW (value) = TREE_OVERFLOW (ovalue);
4822 TREE_CONSTANT_OVERFLOW (value) = TREE_CONSTANT_OVERFLOW (ovalue);
4826 /* Warn about possible alignment problems. Do this here when we will have
4827 instantiated any necessary template types. */
4828 if (STRICT_ALIGNMENT && warn_cast_align
4829 && TREE_CODE (type) == POINTER_TYPE
4830 && TREE_CODE (otype) == POINTER_TYPE
4831 && TREE_CODE (TREE_TYPE (otype)) != VOID_TYPE
4832 && TREE_CODE (TREE_TYPE (otype)) != FUNCTION_TYPE
4833 && COMPLETE_TYPE_P (TREE_TYPE (otype))
4834 && COMPLETE_TYPE_P (TREE_TYPE (type))
4835 && TYPE_ALIGN (TREE_TYPE (type)) > TYPE_ALIGN (TREE_TYPE (otype)))
4836 warning ("cast from `%T' to `%T' increases required alignment of target type",
4839 /* Always produce some operator for an explicit cast,
4840 so we can tell (for -pedantic) that the cast is no lvalue. */
4841 if (TREE_CODE (type) != REFERENCE_TYPE && value == expr
4842 && real_lvalue_p (value))
4843 value = non_lvalue (value);
4848 /* Build an assignment expression of lvalue LHS from value RHS.
4849 MODIFYCODE is the code for a binary operator that we use
4850 to combine the old value of LHS with RHS to get the new value.
4851 Or else MODIFYCODE is NOP_EXPR meaning do a simple assignment.
4853 C++: If MODIFYCODE is INIT_EXPR, then leave references unbashed. */
4856 build_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
4858 register tree result;
4860 tree lhstype = TREE_TYPE (lhs);
4861 tree olhstype = lhstype;
4864 /* Avoid duplicate error messages from operands that had errors. */
4865 if (lhs == error_mark_node || rhs == error_mark_node)
4866 return error_mark_node;
4868 /* Handle control structure constructs used as "lvalues". */
4869 switch (TREE_CODE (lhs))
4871 /* Handle --foo = 5; as these are valid constructs in C++ */
4872 case PREDECREMENT_EXPR:
4873 case PREINCREMENT_EXPR:
4874 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
4875 lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
4876 stabilize_reference (TREE_OPERAND (lhs, 0)),
4877 TREE_OPERAND (lhs, 1));
4878 return build (COMPOUND_EXPR, lhstype,
4880 build_modify_expr (TREE_OPERAND (lhs, 0),
4883 /* Handle (a, b) used as an "lvalue". */
4885 newrhs = build_modify_expr (TREE_OPERAND (lhs, 1),
4887 if (newrhs == error_mark_node)
4888 return error_mark_node;
4889 return build (COMPOUND_EXPR, lhstype,
4890 TREE_OPERAND (lhs, 0), newrhs);
4893 if (TREE_SIDE_EFFECTS (TREE_OPERAND (lhs, 0)))
4894 lhs = build (TREE_CODE (lhs), TREE_TYPE (lhs),
4895 stabilize_reference (TREE_OPERAND (lhs, 0)),
4896 TREE_OPERAND (lhs, 1));
4897 newrhs = build_modify_expr (TREE_OPERAND (lhs, 0), modifycode, rhs);
4898 if (newrhs == error_mark_node)
4899 return error_mark_node;
4900 return build (COMPOUND_EXPR, lhstype, lhs, newrhs);
4902 /* Handle (a ? b : c) used as an "lvalue". */
4905 /* Produce (a ? (b = rhs) : (c = rhs))
4906 except that the RHS goes through a save-expr
4907 so the code to compute it is only emitted once. */
4909 tree preeval = NULL_TREE;
4911 rhs = stabilize_expr (rhs, &preeval);
4913 /* Check this here to avoid odd errors when trying to convert
4914 a throw to the type of the COND_EXPR. */
4915 if (!lvalue_or_else (lhs, "assignment"))
4916 return error_mark_node;
4918 cond = build_conditional_expr
4919 (TREE_OPERAND (lhs, 0),
4920 build_modify_expr (cp_convert (TREE_TYPE (lhs),
4921 TREE_OPERAND (lhs, 1)),
4923 build_modify_expr (cp_convert (TREE_TYPE (lhs),
4924 TREE_OPERAND (lhs, 2)),
4927 if (cond == error_mark_node)
4929 /* Make sure the code to compute the rhs comes out
4930 before the split. */
4931 return build (COMPOUND_EXPR, TREE_TYPE (lhs), preeval, cond);
4938 if (modifycode == INIT_EXPR)
4940 if (TREE_CODE (rhs) == CONSTRUCTOR)
4942 my_friendly_assert (same_type_p (TREE_TYPE (rhs), lhstype),
4944 result = build (INIT_EXPR, lhstype, lhs, rhs);
4945 TREE_SIDE_EFFECTS (result) = 1;
4948 else if (! IS_AGGR_TYPE (lhstype))
4949 /* Do the default thing */;
4952 result = build_special_member_call (lhs, complete_ctor_identifier,
4953 build_tree_list (NULL_TREE, rhs),
4954 TYPE_BINFO (lhstype),
4956 if (result == NULL_TREE)
4957 return error_mark_node;
4963 if (TREE_CODE (lhstype) == REFERENCE_TYPE)
4965 lhs = convert_from_reference (lhs);
4966 olhstype = lhstype = TREE_TYPE (lhs);
4968 lhs = require_complete_type (lhs);
4969 if (lhs == error_mark_node)
4970 return error_mark_node;
4972 if (modifycode == NOP_EXPR)
4974 /* `operator=' is not an inheritable operator. */
4975 if (! IS_AGGR_TYPE (lhstype))
4976 /* Do the default thing */;
4979 result = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL,
4980 lhs, rhs, make_node (NOP_EXPR));
4981 if (result == NULL_TREE)
4982 return error_mark_node;
4989 /* A binary op has been requested. Combine the old LHS
4990 value with the RHS producing the value we should actually
4991 store into the LHS. */
4993 my_friendly_assert (!PROMOTES_TO_AGGR_TYPE (lhstype, REFERENCE_TYPE),
4995 lhs = stabilize_reference (lhs);
4996 newrhs = cp_build_binary_op (modifycode, lhs, rhs);
4997 if (newrhs == error_mark_node)
4999 error (" in evaluation of `%Q(%#T, %#T)'", modifycode,
5000 TREE_TYPE (lhs), TREE_TYPE (rhs));
5001 return error_mark_node;
5004 /* Now it looks like a plain assignment. */
5005 modifycode = NOP_EXPR;
5007 my_friendly_assert (TREE_CODE (lhstype) != REFERENCE_TYPE, 20011220);
5008 my_friendly_assert (TREE_CODE (TREE_TYPE (newrhs)) != REFERENCE_TYPE,
5012 /* Handle a cast used as an "lvalue".
5013 We have already performed any binary operator using the value as cast.
5014 Now convert the result to the cast type of the lhs,
5015 and then true type of the lhs and store it there;
5016 then convert result back to the cast type to be the value
5017 of the assignment. */
5019 switch (TREE_CODE (lhs))
5024 case FIX_TRUNC_EXPR:
5025 case FIX_FLOOR_EXPR:
5026 case FIX_ROUND_EXPR:
5029 tree inner_lhs = TREE_OPERAND (lhs, 0);
5032 if (TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5033 || TREE_CODE (TREE_TYPE (newrhs)) == FUNCTION_TYPE
5034 || TREE_CODE (TREE_TYPE (newrhs)) == METHOD_TYPE
5035 || TREE_CODE (TREE_TYPE (newrhs)) == OFFSET_TYPE)
5036 newrhs = decay_conversion (newrhs);
5038 /* ISO C++ 5.4/1: The result is an lvalue if T is a reference
5039 type, otherwise the result is an rvalue. */
5040 if (! lvalue_p (lhs))
5041 pedwarn ("ISO C++ forbids cast to non-reference type used as lvalue");
5043 result = build_modify_expr (inner_lhs, NOP_EXPR,
5044 cp_convert (TREE_TYPE (inner_lhs),
5045 cp_convert (lhstype, newrhs)));
5046 if (result == error_mark_node)
5048 return cp_convert (TREE_TYPE (lhs), result);
5055 /* Now we have handled acceptable kinds of LHS that are not truly lvalues.
5056 Reject anything strange now. */
5058 if (!lvalue_or_else (lhs, "assignment"))
5059 return error_mark_node;
5061 /* Warn about modifying something that is `const'. Don't warn if
5062 this is initialization. */
5063 if (modifycode != INIT_EXPR
5064 && (TREE_READONLY (lhs) || CP_TYPE_CONST_P (lhstype)
5065 /* Functions are not modifiable, even though they are
5067 || TREE_CODE (TREE_TYPE (lhs)) == FUNCTION_TYPE
5068 || TREE_CODE (TREE_TYPE (lhs)) == METHOD_TYPE
5069 /* If it's an aggregate and any field is const, then it is
5070 effectively const. */
5071 || (CLASS_TYPE_P (lhstype)
5072 && C_TYPE_FIELDS_READONLY (lhstype))))
5073 readonly_error (lhs, "assignment", 0);
5075 /* If storing into a structure or union member, it has probably been
5076 given type `int'. Compute the type that would go with the actual
5077 amount of storage the member occupies. */
5079 if (TREE_CODE (lhs) == COMPONENT_REF
5080 && (TREE_CODE (lhstype) == INTEGER_TYPE
5081 || TREE_CODE (lhstype) == REAL_TYPE
5082 || TREE_CODE (lhstype) == ENUMERAL_TYPE))
5084 lhstype = TREE_TYPE (get_unwidened (lhs, 0));
5086 /* If storing in a field that is in actuality a short or narrower
5087 than one, we must store in the field in its actual type. */
5089 if (lhstype != TREE_TYPE (lhs))
5091 lhs = copy_node (lhs);
5092 TREE_TYPE (lhs) = lhstype;
5096 /* Convert new value to destination type. */
5098 if (TREE_CODE (lhstype) == ARRAY_TYPE)
5102 if (!same_or_base_type_p (TYPE_MAIN_VARIANT (lhstype),
5103 TYPE_MAIN_VARIANT (TREE_TYPE (rhs))))
5105 error ("incompatible types in assignment of `%T' to `%T'",
5106 TREE_TYPE (rhs), lhstype);
5107 return error_mark_node;
5110 /* Allow array assignment in compiler-generated code. */
5111 if (! DECL_ARTIFICIAL (current_function_decl))
5112 pedwarn ("ISO C++ forbids assignment of arrays");
5114 from_array = TREE_CODE (TREE_TYPE (newrhs)) == ARRAY_TYPE
5115 ? 1 + (modifycode != INIT_EXPR): 0;
5116 return build_vec_init (lhs, NULL_TREE, newrhs, from_array);
5119 if (modifycode == INIT_EXPR)
5120 newrhs = convert_for_initialization (lhs, lhstype, newrhs, LOOKUP_NORMAL,
5121 "initialization", NULL_TREE, 0);
5124 /* Avoid warnings on enum bit fields. */
5125 if (TREE_CODE (olhstype) == ENUMERAL_TYPE
5126 && TREE_CODE (lhstype) == INTEGER_TYPE)
5128 newrhs = convert_for_assignment (olhstype, newrhs, "assignment",
5130 newrhs = convert_force (lhstype, newrhs, 0);
5133 newrhs = convert_for_assignment (lhstype, newrhs, "assignment",
5135 if (TREE_CODE (newrhs) == CALL_EXPR
5136 && TYPE_NEEDS_CONSTRUCTING (lhstype))
5137 newrhs = build_cplus_new (lhstype, newrhs);
5139 /* Can't initialize directly from a TARGET_EXPR, since that would
5140 cause the lhs to be constructed twice, and possibly result in
5141 accidental self-initialization. So we force the TARGET_EXPR to be
5142 expanded without a target. */
5143 if (TREE_CODE (newrhs) == TARGET_EXPR)
5144 newrhs = build (COMPOUND_EXPR, TREE_TYPE (newrhs), newrhs,
5145 TREE_OPERAND (newrhs, 0));
5148 if (newrhs == error_mark_node)
5149 return error_mark_node;
5151 result = build (modifycode == NOP_EXPR ? MODIFY_EXPR : INIT_EXPR,
5152 lhstype, lhs, newrhs);
5154 TREE_SIDE_EFFECTS (result) = 1;
5156 /* If we got the LHS in a different type for storing in,
5157 convert the result back to the nominal type of LHS
5158 so that the value we return always has the same type
5159 as the LHS argument. */
5161 if (olhstype == TREE_TYPE (result))
5163 /* Avoid warnings converting integral types back into enums
5164 for enum bit fields. */
5165 if (TREE_CODE (TREE_TYPE (result)) == INTEGER_TYPE
5166 && TREE_CODE (olhstype) == ENUMERAL_TYPE)
5168 result = build (COMPOUND_EXPR, olhstype, result, olhs);
5169 TREE_NO_UNUSED_WARNING (result) = 1;
5172 return convert_for_assignment (olhstype, result, "assignment",
5177 build_x_modify_expr (tree lhs, enum tree_code modifycode, tree rhs)
5179 if (processing_template_decl)
5180 return build_min_nt (MODOP_EXPR, lhs,
5181 build_min_nt (modifycode, NULL_TREE, NULL_TREE), rhs);
5183 if (modifycode != NOP_EXPR)
5185 tree rval = build_new_op (MODIFY_EXPR, LOOKUP_NORMAL, lhs, rhs,
5186 make_node (modifycode));
5190 return build_modify_expr (lhs, modifycode, rhs);
5194 /* Get difference in deltas for different pointer to member function
5195 types. Return integer_zero_node, if FROM cannot be converted to a
5196 TO type. If FORCE is true, then allow reverse conversions as well.
5198 Note that the naming of FROM and TO is kind of backwards; the return
5199 value is what we add to a TO in order to get a FROM. They are named
5200 this way because we call this function to find out how to convert from
5201 a pointer to member of FROM to a pointer to member of TO. */
5204 get_delta_difference (tree from, tree to, int force)
5206 tree delta = integer_zero_node;
5211 binfo = lookup_base (to, from, ba_check, &kind);
5212 if (kind == bk_inaccessible || kind == bk_ambig)
5214 error (" in pointer to member function conversion");
5221 error_not_base_type (from, to);
5222 error (" in pointer to member conversion");
5225 binfo = lookup_base (from, to, ba_check, &kind);
5228 virt_binfo = binfo_from_vbase (binfo);
5232 /* This is a reinterpret cast, we choose to do nothing. */
5233 warning ("pointer to member cast via virtual base `%T'",
5234 BINFO_TYPE (virt_binfo));
5237 delta = BINFO_OFFSET (binfo);
5238 delta = cp_convert (ptrdiff_type_node, delta);
5239 delta = cp_build_binary_op (MINUS_EXPR,
5246 virt_binfo = binfo_from_vbase (binfo);
5249 /* This is a reinterpret cast, we choose to do nothing. */
5251 warning ("pointer to member cast via virtual base `%T'",
5252 BINFO_TYPE (virt_binfo));
5254 error ("pointer to member conversion via virtual base `%T'",
5255 BINFO_TYPE (virt_binfo));
5258 delta = BINFO_OFFSET (binfo);
5260 return cp_convert (ptrdiff_type_node, delta);
5263 /* Return a constructor for the pointer-to-member-function TYPE using
5264 the other components as specified. */
5267 build_ptrmemfunc1 (tree type, tree delta, tree pfn)
5273 /* Pull the FIELD_DECLs out of the type. */
5274 pfn_field = TYPE_FIELDS (type);
5275 delta_field = TREE_CHAIN (pfn_field);
5277 /* Make sure DELTA has the type we want. */
5278 delta = convert_and_check (delta_type_node, delta);
5280 /* Finish creating the initializer. */
5281 u = tree_cons (pfn_field, pfn,
5282 build_tree_list (delta_field, delta));
5283 u = build_constructor (type, u);
5284 TREE_CONSTANT (u) = TREE_CONSTANT (pfn) && TREE_CONSTANT (delta);
5285 TREE_STATIC (u) = (TREE_CONSTANT (u)
5286 && (initializer_constant_valid_p (pfn, TREE_TYPE (pfn))
5288 && (initializer_constant_valid_p (delta, TREE_TYPE (delta))
5293 /* Build a constructor for a pointer to member function. It can be
5294 used to initialize global variables, local variable, or used
5295 as a value in expressions. TYPE is the POINTER to METHOD_TYPE we
5298 If FORCE is nonzero, then force this conversion, even if
5299 we would rather not do it. Usually set when using an explicit
5302 Return error_mark_node, if something goes wrong. */
5305 build_ptrmemfunc (tree type, tree pfn, int force)
5311 if (error_operand_p (pfn))
5312 return error_mark_node;
5314 pfn_type = TREE_TYPE (pfn);
5315 to_type = build_ptrmemfunc_type (type);
5317 /* Handle multiple conversions of pointer to member functions. */
5318 if (TYPE_PTRMEMFUNC_P (pfn_type))
5320 tree delta = NULL_TREE;
5321 tree npfn = NULL_TREE;
5325 && !can_convert_arg (to_type, TREE_TYPE (pfn), pfn))
5326 error ("invalid conversion to type `%T' from type `%T'",
5329 n = get_delta_difference (TYPE_PTRMEMFUNC_OBJECT_TYPE (pfn_type),
5330 TYPE_PTRMEMFUNC_OBJECT_TYPE (to_type),
5333 /* We don't have to do any conversion to convert a
5334 pointer-to-member to its own type. But, we don't want to
5335 just return a PTRMEM_CST if there's an explicit cast; that
5336 cast should make the expression an invalid template argument. */
5337 if (TREE_CODE (pfn) != PTRMEM_CST)
5339 if (same_type_p (to_type, pfn_type))
5341 else if (integer_zerop (n))
5342 return build_reinterpret_cast (to_type, pfn);
5345 if (TREE_SIDE_EFFECTS (pfn))
5346 pfn = save_expr (pfn);
5348 /* Obtain the function pointer and the current DELTA. */
5349 if (TREE_CODE (pfn) == PTRMEM_CST)
5350 expand_ptrmemfunc_cst (pfn, &delta, &npfn);
5353 npfn = build_ptrmemfunc_access_expr (pfn, pfn_identifier);
5354 delta = build_ptrmemfunc_access_expr (pfn, delta_identifier);
5357 /* Just adjust the DELTA field. */
5358 delta = cp_convert (ptrdiff_type_node, delta);
5359 if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_delta)
5360 n = cp_build_binary_op (LSHIFT_EXPR, n, integer_one_node);
5361 delta = cp_build_binary_op (PLUS_EXPR, delta, n);
5362 return build_ptrmemfunc1 (to_type, delta, npfn);
5365 /* Handle null pointer to member function conversions. */
5366 if (integer_zerop (pfn))
5368 pfn = build_c_cast (type, integer_zero_node);
5369 return build_ptrmemfunc1 (to_type,
5374 if (type_unknown_p (pfn))
5375 return instantiate_type (type, pfn, tf_error | tf_warning);
5377 fn = TREE_OPERAND (pfn, 0);
5378 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
5379 return make_ptrmem_cst (to_type, fn);
5382 /* Return the DELTA, IDX, PFN, and DELTA2 values for the PTRMEM_CST
5385 ??? There is no consistency as to the types returned for the above
5386 values. Some code acts as if its a sizetype and some as if its
5387 integer_type_node. */
5390 expand_ptrmemfunc_cst (tree cst, tree *delta, tree *pfn)
5392 tree type = TREE_TYPE (cst);
5393 tree fn = PTRMEM_CST_MEMBER (cst);
5394 tree ptr_class, fn_class;
5396 my_friendly_assert (TREE_CODE (fn) == FUNCTION_DECL, 0);
5398 /* The class that the function belongs to. */
5399 fn_class = DECL_CONTEXT (fn);
5401 /* The class that we're creating a pointer to member of. */
5402 ptr_class = TYPE_PTRMEMFUNC_OBJECT_TYPE (type);
5404 /* First, calculate the adjustment to the function's class. */
5405 *delta = get_delta_difference (fn_class, ptr_class, /*force=*/0);
5407 if (!DECL_VIRTUAL_P (fn))
5408 *pfn = convert (TYPE_PTRMEMFUNC_FN_TYPE (type), build_addr_func (fn));
5411 /* If we're dealing with a virtual function, we have to adjust 'this'
5412 again, to point to the base which provides the vtable entry for
5413 fn; the call will do the opposite adjustment. */
5414 tree orig_class = DECL_CONTEXT (fn);
5415 tree binfo = binfo_or_else (orig_class, fn_class);
5416 *delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
5417 *delta, BINFO_OFFSET (binfo)));
5419 /* We set PFN to the vtable offset at which the function can be
5420 found, plus one (unless ptrmemfunc_vbit_in_delta, in which
5421 case delta is shifted left, and then incremented). */
5422 *pfn = DECL_VINDEX (fn);
5423 *pfn = fold (build (MULT_EXPR, integer_type_node, *pfn,
5424 TYPE_SIZE_UNIT (vtable_entry_type)));
5426 switch (TARGET_PTRMEMFUNC_VBIT_LOCATION)
5428 case ptrmemfunc_vbit_in_pfn:
5429 *pfn = fold (build (PLUS_EXPR, integer_type_node, *pfn,
5433 case ptrmemfunc_vbit_in_delta:
5434 *delta = fold (build (LSHIFT_EXPR, TREE_TYPE (*delta),
5435 *delta, integer_one_node));
5436 *delta = fold (build (PLUS_EXPR, TREE_TYPE (*delta),
5437 *delta, integer_one_node));
5444 *pfn = fold (build1 (NOP_EXPR, TYPE_PTRMEMFUNC_FN_TYPE (type),
5449 /* Return an expression for PFN from the pointer-to-member function
5453 pfn_from_ptrmemfunc (tree t)
5455 if (TREE_CODE (t) == PTRMEM_CST)
5460 expand_ptrmemfunc_cst (t, &delta, &pfn);
5465 return build_ptrmemfunc_access_expr (t, pfn_identifier);
5468 /* Expression EXPR is about to be implicitly converted to TYPE. Warn
5469 if this is a potentially dangerous thing to do. Returns a possibly
5473 dubious_conversion_warnings (tree type, tree expr,
5474 const char *errtype, tree fndecl, int parmnum)
5476 type = non_reference (type);
5478 /* Issue warnings about peculiar, but valid, uses of NULL. */
5479 if (ARITHMETIC_TYPE_P (type) && expr == null_node)
5482 warning ("passing NULL used for non-pointer %s %P of `%D'",
5483 errtype, parmnum, fndecl);
5485 warning ("%s to non-pointer type `%T' from NULL", errtype, type);
5488 /* Warn about assigning a floating-point type to an integer type. */
5489 if (TREE_CODE (TREE_TYPE (expr)) == REAL_TYPE
5490 && TREE_CODE (type) == INTEGER_TYPE)
5493 warning ("passing `%T' for %s %P of `%D'",
5494 TREE_TYPE (expr), errtype, parmnum, fndecl);
5496 warning ("%s to `%T' from `%T'", errtype, type, TREE_TYPE (expr));
5498 /* And warn about assigning a negative value to an unsigned
5500 else if (TREE_UNSIGNED (type) && TREE_CODE (type) != BOOLEAN_TYPE)
5502 if (TREE_CODE (expr) == INTEGER_CST
5503 && TREE_NEGATED_INT (expr))
5506 warning ("passing negative value `%E' for %s %P of `%D'",
5507 expr, errtype, parmnum, fndecl);
5509 warning ("%s of negative value `%E' to `%T'",
5510 errtype, expr, type);
5513 overflow_warning (expr);
5515 if (TREE_CONSTANT (expr))
5521 /* Convert value RHS to type TYPE as preparation for an assignment to
5522 an lvalue of type TYPE. ERRTYPE is a string to use in error
5523 messages: "assignment", "return", etc. If FNDECL is non-NULL, we
5524 are doing the conversion in order to pass the PARMNUMth argument of
5528 convert_for_assignment (tree type, tree rhs,
5529 const char *errtype, tree fndecl, int parmnum)
5531 register tree rhstype;
5532 register enum tree_code coder;
5534 /* Strip NON_LVALUE_EXPRs since we aren't using as an lvalue. */
5535 if (TREE_CODE (rhs) == NON_LVALUE_EXPR)
5536 rhs = TREE_OPERAND (rhs, 0);
5538 rhstype = TREE_TYPE (rhs);
5539 coder = TREE_CODE (rhstype);
5541 if (rhs == error_mark_node || rhstype == error_mark_node)
5542 return error_mark_node;
5543 if (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node)
5544 return error_mark_node;
5546 rhs = dubious_conversion_warnings (type, rhs, errtype, fndecl, parmnum);
5548 /* The RHS of an assignment cannot have void type. */
5549 if (coder == VOID_TYPE)
5551 error ("void value not ignored as it ought to be");
5552 return error_mark_node;
5555 /* Simplify the RHS if possible. */
5556 if (TREE_CODE (rhs) == CONST_DECL)
5557 rhs = DECL_INITIAL (rhs);
5559 /* We do not use decl_constant_value here because of this case:
5561 const char* const s = "s";
5563 The conversion rules for a string literal are more lax than for a
5564 variable; in particular, a string literal can be converted to a
5565 "char *" but the variable "s" cannot be converted in the same
5566 way. If the conversion is allowed, the optimization should be
5567 performed while creating the converted expression. */
5571 The expression is implicitly converted (clause _conv_) to the
5572 cv-unqualified type of the left operand.
5574 We allow bad conversions here because by the time we get to this point
5575 we are committed to doing the conversion. If we end up doing a bad
5576 conversion, convert_like will complain. */
5577 if (!can_convert_arg_bad (type, rhstype, rhs))
5579 /* When -Wno-pmf-conversions is use, we just silently allow
5580 conversions from pointers-to-members to plain pointers. If
5581 the conversion doesn't work, cp_convert will complain. */
5583 && TYPE_PTR_P (type)
5584 && TYPE_PTRMEMFUNC_P (rhstype))
5585 rhs = cp_convert (strip_top_quals (type), rhs);
5588 /* If the right-hand side has unknown type, then it is an
5589 overloaded function. Call instantiate_type to get error
5591 if (rhstype == unknown_type_node)
5592 instantiate_type (type, rhs, tf_error | tf_warning);
5594 error ("cannot convert `%T' to `%T' for argument `%P' to `%D'",
5595 rhstype, type, parmnum, fndecl);
5597 error ("cannot convert `%T' to `%T' in %s", rhstype, type,
5599 return error_mark_node;
5602 return perform_implicit_conversion (strip_top_quals (type), rhs);
5605 /* Convert RHS to be of type TYPE.
5606 If EXP is nonzero, it is the target of the initialization.
5607 ERRTYPE is a string to use in error messages.
5609 Two major differences between the behavior of
5610 `convert_for_assignment' and `convert_for_initialization'
5611 are that references are bashed in the former, while
5612 copied in the latter, and aggregates are assigned in
5613 the former (operator=) while initialized in the
5616 If using constructor make sure no conversion operator exists, if one does
5617 exist, an ambiguity exists.
5619 If flags doesn't include LOOKUP_COMPLAIN, don't complain about anything. */
5622 convert_for_initialization (tree exp, tree type, tree rhs, int flags,
5623 const char *errtype, tree fndecl, int parmnum)
5625 register enum tree_code codel = TREE_CODE (type);
5626 register tree rhstype;
5627 register enum tree_code coder;
5629 /* build_c_cast puts on a NOP_EXPR to make the result not an lvalue.
5630 Strip such NOP_EXPRs, since RHS is used in non-lvalue context. */
5631 if (TREE_CODE (rhs) == NOP_EXPR
5632 && TREE_TYPE (rhs) == TREE_TYPE (TREE_OPERAND (rhs, 0))
5633 && codel != REFERENCE_TYPE)
5634 rhs = TREE_OPERAND (rhs, 0);
5636 if (rhs == error_mark_node
5637 || (TREE_CODE (rhs) == TREE_LIST && TREE_VALUE (rhs) == error_mark_node))
5638 return error_mark_node;
5640 if (TREE_CODE (TREE_TYPE (rhs)) == REFERENCE_TYPE)
5641 rhs = convert_from_reference (rhs);
5643 if ((TREE_CODE (TREE_TYPE (rhs)) == ARRAY_TYPE
5644 && TREE_CODE (type) != ARRAY_TYPE
5645 && (TREE_CODE (type) != REFERENCE_TYPE
5646 || TREE_CODE (TREE_TYPE (type)) != ARRAY_TYPE))
5647 || (TREE_CODE (TREE_TYPE (rhs)) == FUNCTION_TYPE
5648 && (TREE_CODE (type) != REFERENCE_TYPE
5649 || TREE_CODE (TREE_TYPE (type)) != FUNCTION_TYPE))
5650 || TREE_CODE (TREE_TYPE (rhs)) == METHOD_TYPE)
5651 rhs = decay_conversion (rhs);
5653 rhstype = TREE_TYPE (rhs);
5654 coder = TREE_CODE (rhstype);
5656 if (coder == ERROR_MARK)
5657 return error_mark_node;
5659 /* We accept references to incomplete types, so we can
5660 return here before checking if RHS is of complete type. */
5662 if (codel == REFERENCE_TYPE)
5664 /* This should eventually happen in convert_arguments. */
5665 int savew = 0, savee = 0;
5668 savew = warningcount, savee = errorcount;
5669 rhs = initialize_reference (type, rhs, /*decl=*/NULL_TREE);
5672 if (warningcount > savew)
5673 cp_warning_at ("in passing argument %P of `%+D'", parmnum, fndecl);
5674 else if (errorcount > savee)
5675 cp_error_at ("in passing argument %P of `%+D'", parmnum, fndecl);
5681 exp = require_complete_type (exp);
5682 if (exp == error_mark_node)
5683 return error_mark_node;
5685 rhstype = non_reference (rhstype);
5687 type = complete_type (type);
5689 if (IS_AGGR_TYPE (type))
5690 return ocp_convert (type, rhs, CONV_IMPLICIT|CONV_FORCE_TEMP, flags);
5692 return convert_for_assignment (type, rhs, errtype, fndecl, parmnum);
5695 /* Expand an ASM statement with operands, handling output operands
5696 that are not variables or INDIRECT_REFS by transforming such
5697 cases into cases that expand_asm_operands can handle.
5699 Arguments are same as for expand_asm_operands.
5701 We don't do default conversions on all inputs, because it can screw
5702 up operands that are expected to be in memory. */
5705 c_expand_asm_operands (tree string, tree outputs, tree inputs, tree clobbers,
5706 int vol, const char *filename, int line)
5708 int noutputs = list_length (outputs);
5710 /* o[I] is the place that output number I should be written. */
5711 register tree *o = alloca (noutputs * sizeof (tree));
5714 /* Record the contents of OUTPUTS before it is modified. */
5715 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
5716 o[i] = TREE_VALUE (tail);
5718 /* Generate the ASM_OPERANDS insn;
5719 store into the TREE_VALUEs of OUTPUTS some trees for
5720 where the values were actually stored. */
5721 expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line);
5723 /* Copy all the intermediate outputs into the specified outputs. */
5724 for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++)
5726 if (o[i] != TREE_VALUE (tail))
5728 expand_expr (build_modify_expr (o[i], NOP_EXPR, TREE_VALUE (tail)),
5729 const0_rtx, VOIDmode, EXPAND_NORMAL);
5732 /* Restore the original value so that it's correct the next
5733 time we expand this function. */
5734 TREE_VALUE (tail) = o[i];
5736 /* Detect modification of read-only values.
5737 (Otherwise done by build_modify_expr.) */
5740 tree type = TREE_TYPE (o[i]);
5741 if (type != error_mark_node
5742 && (CP_TYPE_CONST_P (type)
5743 || (CLASS_TYPE_P (type) && C_TYPE_FIELDS_READONLY (type))))
5744 readonly_error (o[i], "modification by `asm'", 1);
5748 /* Those MODIFY_EXPRs could do autoincrements. */
5752 /* If RETVAL is the address of, or a reference to, a local variable or
5753 temporary give an appropriate warning. */
5756 maybe_warn_about_returning_address_of_local (tree retval)
5758 tree valtype = TREE_TYPE (DECL_RESULT (current_function_decl));
5759 tree whats_returned = retval;
5763 if (TREE_CODE (whats_returned) == COMPOUND_EXPR)
5764 whats_returned = TREE_OPERAND (whats_returned, 1);
5765 else if (TREE_CODE (whats_returned) == CONVERT_EXPR
5766 || TREE_CODE (whats_returned) == NON_LVALUE_EXPR
5767 || TREE_CODE (whats_returned) == NOP_EXPR)
5768 whats_returned = TREE_OPERAND (whats_returned, 0);
5773 if (TREE_CODE (whats_returned) != ADDR_EXPR)
5775 whats_returned = TREE_OPERAND (whats_returned, 0);
5777 if (TREE_CODE (valtype) == REFERENCE_TYPE)
5779 if (TREE_CODE (whats_returned) == AGGR_INIT_EXPR
5780 || TREE_CODE (whats_returned) == TARGET_EXPR)
5782 warning ("returning reference to temporary");
5785 if (TREE_CODE (whats_returned) == VAR_DECL
5786 && DECL_NAME (whats_returned)
5787 && TEMP_NAME_P (DECL_NAME (whats_returned)))
5789 warning ("reference to non-lvalue returned");
5794 if (TREE_CODE (whats_returned) == VAR_DECL
5795 && DECL_NAME (whats_returned)
5796 && DECL_FUNCTION_SCOPE_P (whats_returned)
5797 && !(TREE_STATIC (whats_returned)
5798 || TREE_PUBLIC (whats_returned)))
5800 if (TREE_CODE (valtype) == REFERENCE_TYPE)
5801 cp_warning_at ("reference to local variable `%D' returned",
5804 cp_warning_at ("address of local variable `%D' returned",
5810 /* Check that returning RETVAL from the current function is valid.
5811 Return an expression explicitly showing all conversions required to
5812 change RETVAL into the function return type, and to assign it to
5813 the DECL_RESULT for the function. */
5816 check_return_expr (tree retval)
5819 /* The type actually returned by the function, after any
5822 int fn_returns_value_p;
5824 /* A `volatile' function is one that isn't supposed to return, ever.
5825 (This is a G++ extension, used to get better code for functions
5826 that call the `volatile' function.) */
5827 if (TREE_THIS_VOLATILE (current_function_decl))
5828 warning ("function declared `noreturn' has a `return' statement");
5830 /* Check for various simple errors. */
5831 if (DECL_DESTRUCTOR_P (current_function_decl))
5834 error ("returning a value from a destructor");
5837 else if (DECL_CONSTRUCTOR_P (current_function_decl))
5839 if (in_function_try_handler)
5840 /* If a return statement appears in a handler of the
5841 function-try-block of a constructor, the program is ill-formed. */
5842 error ("cannot return from a handler of a function-try-block of a constructor");
5844 /* You can't return a value from a constructor. */
5845 error ("returning a value from a constructor");
5849 if (processing_template_decl)
5851 current_function_returns_value = 1;
5855 /* When no explicit return-value is given in a function with a named
5856 return value, the named return value is used. */
5857 result = DECL_RESULT (current_function_decl);
5858 valtype = TREE_TYPE (result);
5859 my_friendly_assert (valtype != NULL_TREE, 19990924);
5860 fn_returns_value_p = !VOID_TYPE_P (valtype);
5861 if (!retval && DECL_NAME (result) && fn_returns_value_p)
5864 /* Check for a return statement with no return value in a function
5865 that's supposed to return a value. */
5866 if (!retval && fn_returns_value_p)
5868 pedwarn ("return-statement with no value, in function returning '%T'",
5870 /* Clear this, so finish_function won't say that we reach the
5871 end of a non-void function (which we don't, we gave a
5873 current_function_returns_null = 0;
5875 /* Check for a return statement with a value in a function that
5876 isn't supposed to return a value. */
5877 else if (retval && !fn_returns_value_p)
5879 if (VOID_TYPE_P (TREE_TYPE (retval)))
5880 /* You can return a `void' value from a function of `void'
5881 type. In that case, we have to evaluate the expression for
5882 its side-effects. */
5883 finish_expr_stmt (retval);
5885 pedwarn ("return-statement with a value, in function "
5886 "returning 'void'");
5888 current_function_returns_null = 1;
5890 /* There's really no value to return, after all. */
5894 /* Remember that this function can sometimes return without a
5896 current_function_returns_null = 1;
5898 /* Remember that this function did return a value. */
5899 current_function_returns_value = 1;
5901 /* Only operator new(...) throw(), can return NULL [expr.new/13]. */
5902 if ((DECL_OVERLOADED_OPERATOR_P (current_function_decl) == NEW_EXPR
5903 || DECL_OVERLOADED_OPERATOR_P (current_function_decl) == VEC_NEW_EXPR)
5904 && !TYPE_NOTHROW_P (TREE_TYPE (current_function_decl))
5906 && null_ptr_cst_p (retval))
5907 warning ("`operator new' must not return NULL unless it is declared `throw()' (or -fcheck-new is in effect)");
5909 /* Effective C++ rule 15. See also start_function. */
5911 && DECL_NAME (current_function_decl) == ansi_assopname(NOP_EXPR)
5912 && retval != current_class_ref)
5913 warning ("`operator=' should return a reference to `*this'");
5915 /* The fabled Named Return Value optimization, as per [class.copy]/15:
5917 [...] For a function with a class return type, if the expression
5918 in the return statement is the name of a local object, and the cv-
5919 unqualified type of the local object is the same as the function
5920 return type, an implementation is permitted to omit creating the tem-
5921 porary object to hold the function return value [...]
5923 So, if this is a value-returning function that always returns the same
5924 local variable, remember it.
5926 It might be nice to be more flexible, and choose the first suitable
5927 variable even if the function sometimes returns something else, but
5928 then we run the risk of clobbering the variable we chose if the other
5929 returned expression uses the chosen variable somehow. And people expect
5930 this restriction, anyway. (jason 2000-11-19)
5932 See finish_function, genrtl_start_function, and declare_return_variable
5933 for other pieces of this optimization. */
5935 if (fn_returns_value_p && flag_elide_constructors)
5937 if (retval != NULL_TREE
5938 && (current_function_return_value == NULL_TREE
5939 || current_function_return_value == retval)
5940 && TREE_CODE (retval) == VAR_DECL
5941 && DECL_CONTEXT (retval) == current_function_decl
5942 && ! TREE_STATIC (retval)
5943 && (DECL_ALIGN (retval)
5944 >= DECL_ALIGN (DECL_RESULT (current_function_decl)))
5945 && same_type_p ((TYPE_MAIN_VARIANT
5946 (TREE_TYPE (retval))),
5948 (TREE_TYPE (TREE_TYPE (current_function_decl))))))
5949 current_function_return_value = retval;
5951 current_function_return_value = error_mark_node;
5954 /* We don't need to do any conversions when there's nothing being
5956 if (!retval || retval == error_mark_node)
5959 /* Do any required conversions. */
5960 if (retval == result || DECL_CONSTRUCTOR_P (current_function_decl))
5961 /* No conversions are required. */
5965 /* The type the function is declared to return. */
5966 tree functype = TREE_TYPE (TREE_TYPE (current_function_decl));
5968 /* First convert the value to the function's return type, then
5969 to the type of return value's location to handle the
5970 case that functype is smaller than the valtype. */
5971 retval = convert_for_initialization
5972 (NULL_TREE, functype, retval, LOOKUP_NORMAL|LOOKUP_ONLYCONVERTING,
5973 "return", NULL_TREE, 0);
5974 retval = convert (valtype, retval);
5976 /* If the conversion failed, treat this just like `return;'. */
5977 if (retval == error_mark_node)
5979 /* We can't initialize a register from a AGGR_INIT_EXPR. */
5980 else if (! current_function_returns_struct
5981 && TREE_CODE (retval) == TARGET_EXPR
5982 && TREE_CODE (TREE_OPERAND (retval, 1)) == AGGR_INIT_EXPR)
5983 retval = build (COMPOUND_EXPR, TREE_TYPE (retval), retval,
5984 TREE_OPERAND (retval, 0));
5986 maybe_warn_about_returning_address_of_local (retval);
5989 /* Actually copy the value returned into the appropriate location. */
5990 if (retval && retval != result)
5991 retval = build (INIT_EXPR, TREE_TYPE (result), result, retval);
5997 /* Returns nonzero if the pointer-type FROM can be converted to the
5998 pointer-type TO via a qualification conversion. If CONSTP is -1,
5999 then we return nonzero if the pointers are similar, and the
6000 cv-qualification signature of FROM is a proper subset of that of TO.
6002 If CONSTP is positive, then all outer pointers have been
6006 comp_ptr_ttypes_real (tree to, tree from, int constp)
6008 bool to_more_cv_qualified = false;
6010 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6012 if (TREE_CODE (to) != TREE_CODE (from))
6015 if (TREE_CODE (from) == OFFSET_TYPE
6016 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6017 TYPE_OFFSET_BASETYPE (to)))
6020 /* Const and volatile mean something different for function types,
6021 so the usual checks are not appropriate. */
6022 if (TREE_CODE (to) != FUNCTION_TYPE && TREE_CODE (to) != METHOD_TYPE)
6024 if (!at_least_as_qualified_p (to, from))
6027 if (!at_least_as_qualified_p (from, to))
6031 to_more_cv_qualified = true;
6035 constp &= TYPE_READONLY (to);
6038 if (TREE_CODE (to) != POINTER_TYPE)
6039 return ((constp >= 0 || to_more_cv_qualified)
6040 && same_type_ignoring_top_level_qualifiers_p (to, from));
6044 /* When comparing, say, char ** to char const **, this function takes
6045 the 'char *' and 'char const *'. Do not pass non-pointer/reference
6046 types to this function. */
6049 comp_ptr_ttypes (tree to, tree from)
6051 return comp_ptr_ttypes_real (to, from, 1);
6054 /* Returns 1 if to and from are (possibly multi-level) pointers to the same
6055 type or inheritance-related types, regardless of cv-quals. */
6058 ptr_reasonably_similar (tree to, tree from)
6060 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6062 /* Any target type is similar enough to void. */
6063 if (TREE_CODE (to) == VOID_TYPE
6064 || TREE_CODE (from) == VOID_TYPE)
6067 if (TREE_CODE (to) != TREE_CODE (from))
6070 if (TREE_CODE (from) == OFFSET_TYPE
6071 && comptypes (TYPE_OFFSET_BASETYPE (to),
6072 TYPE_OFFSET_BASETYPE (from),
6073 COMPARE_BASE | COMPARE_DERIVED))
6076 if (TREE_CODE (to) == INTEGER_TYPE
6077 && TYPE_PRECISION (to) == TYPE_PRECISION (from))
6080 if (TREE_CODE (to) == FUNCTION_TYPE)
6083 if (TREE_CODE (to) != POINTER_TYPE)
6085 (TYPE_MAIN_VARIANT (to), TYPE_MAIN_VARIANT (from),
6086 COMPARE_BASE | COMPARE_DERIVED);
6090 /* Like comp_ptr_ttypes, for const_cast. */
6093 comp_ptr_ttypes_const (tree to, tree from)
6095 for (; ; to = TREE_TYPE (to), from = TREE_TYPE (from))
6097 if (TREE_CODE (to) != TREE_CODE (from))
6100 if (TREE_CODE (from) == OFFSET_TYPE
6101 && same_type_p (TYPE_OFFSET_BASETYPE (from),
6102 TYPE_OFFSET_BASETYPE (to)))
6105 if (TREE_CODE (to) != POINTER_TYPE)
6106 return same_type_ignoring_top_level_qualifiers_p (to, from);
6110 /* Returns the type qualifiers for this type, including the qualifiers on the
6111 elements for an array type. */
6114 cp_type_quals (tree type)
6116 type = strip_array_types (type);
6117 if (type == error_mark_node)
6118 return TYPE_UNQUALIFIED;
6119 return TYPE_QUALS (type);
6122 /* Returns nonzero if the TYPE contains a mutable member */
6125 cp_has_mutable_p (tree type)
6127 type = strip_array_types (type);
6129 return CLASS_TYPE_P (type) && CLASSTYPE_HAS_MUTABLE (type);
6132 /* Subroutine of casts_away_constness. Make T1 and T2 point at
6133 exemplar types such that casting T1 to T2 is casting away castness
6134 if and only if there is no implicit conversion from T1 to T2. */
6137 casts_away_constness_r (tree *t1, tree *t2)
6142 /* [expr.const.cast]
6144 For multi-level pointer to members and multi-level mixed pointers
6145 and pointers to members (conv.qual), the "member" aspect of a
6146 pointer to member level is ignored when determining if a const
6147 cv-qualifier has been cast away. */
6148 if (TYPE_PTRMEM_P (*t1))
6149 *t1 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t1));
6150 if (TYPE_PTRMEM_P (*t2))
6151 *t2 = build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (*t2));
6153 /* [expr.const.cast]
6155 For two pointer types:
6157 X1 is T1cv1,1 * ... cv1,N * where T1 is not a pointer type
6158 X2 is T2cv2,1 * ... cv2,M * where T2 is not a pointer type
6161 casting from X1 to X2 casts away constness if, for a non-pointer
6162 type T there does not exist an implicit conversion (clause
6165 Tcv1,(N-K+1) * cv1,(N-K+2) * ... cv1,N *
6169 Tcv2,(M-K+1) * cv2,(M-K+2) * ... cv2,M *. */
6171 if (TREE_CODE (*t1) != POINTER_TYPE
6172 || TREE_CODE (*t2) != POINTER_TYPE)
6174 *t1 = cp_build_qualified_type (void_type_node,
6175 cp_type_quals (*t1));
6176 *t2 = cp_build_qualified_type (void_type_node,
6177 cp_type_quals (*t2));
6181 quals1 = cp_type_quals (*t1);
6182 quals2 = cp_type_quals (*t2);
6183 *t1 = TREE_TYPE (*t1);
6184 *t2 = TREE_TYPE (*t2);
6185 casts_away_constness_r (t1, t2);
6186 *t1 = build_pointer_type (*t1);
6187 *t2 = build_pointer_type (*t2);
6188 *t1 = cp_build_qualified_type (*t1, quals1);
6189 *t2 = cp_build_qualified_type (*t2, quals2);
6192 /* Returns nonzero if casting from TYPE1 to TYPE2 casts away
6196 casts_away_constness (tree t1, tree t2)
6198 if (TREE_CODE (t2) == REFERENCE_TYPE)
6200 /* [expr.const.cast]
6202 Casting from an lvalue of type T1 to an lvalue of type T2
6203 using a reference cast casts away constness if a cast from an
6204 rvalue of type "pointer to T1" to the type "pointer to T2"
6205 casts away constness. */
6206 t1 = (TREE_CODE (t1) == REFERENCE_TYPE ? TREE_TYPE (t1) : t1);
6207 return casts_away_constness (build_pointer_type (t1),
6208 build_pointer_type (TREE_TYPE (t2)));
6211 if (TYPE_PTRMEM_P (t1) && TYPE_PTRMEM_P (t2))
6212 /* [expr.const.cast]
6214 Casting from an rvalue of type "pointer to data member of X
6215 of type T1" to the type "pointer to data member of Y of type
6216 T2" casts away constness if a cast from an rvalue of type
6217 "pointer to T1" to the type "pointer to T2" casts away
6219 return casts_away_constness
6220 (build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t1)),
6221 build_pointer_type (TYPE_PTRMEM_POINTED_TO_TYPE (t2)));
6223 /* Casting away constness is only something that makes sense for
6224 pointer or reference types. */
6225 if (TREE_CODE (t1) != POINTER_TYPE
6226 || TREE_CODE (t2) != POINTER_TYPE)
6229 /* Top-level qualifiers don't matter. */
6230 t1 = TYPE_MAIN_VARIANT (t1);
6231 t2 = TYPE_MAIN_VARIANT (t2);
6232 casts_away_constness_r (&t1, &t2);
6233 if (!can_convert (t2, t1))
6239 /* If T is a REFERENCE_TYPE return the type to which T refers.
6240 Otherwise, return T itself. */
6243 non_reference (tree t)
6245 if (TREE_CODE (t) == REFERENCE_TYPE)