1 /* Breadth-first and depth-first routines for
2 searching multiple-inheritance lattice for GNU C++.
3 Copyright (C) 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
4 1999, 2000, 2002, 2003 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING. If not, write to
21 the Free Software Foundation, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 /* High-level class interface. */
28 #include "coretypes.h"
39 /* Obstack used for remembering decision points of breadth-first. */
41 static struct obstack search_obstack;
43 /* Methods for pushing and popping objects to and from obstacks. */
46 push_stack_level (obstack, tp, size)
47 struct obstack *obstack;
48 char *tp; /* Sony NewsOS 5.0 compiler doesn't like void * here. */
51 struct stack_level *stack;
52 obstack_grow (obstack, tp, size);
53 stack = (struct stack_level *) ((char*)obstack_next_free (obstack) - size);
54 obstack_finish (obstack);
55 stack->obstack = obstack;
56 stack->first = (tree *) obstack_base (obstack);
57 stack->limit = obstack_room (obstack) / sizeof (tree *);
62 pop_stack_level (stack)
63 struct stack_level *stack;
65 struct stack_level *tem = stack;
66 struct obstack *obstack = tem->obstack;
68 obstack_free (obstack, tem);
72 #define search_level stack_level
73 static struct search_level *search_stack;
77 /* The class dominating the hierarchy. */
79 /* A pointer to a complete object of the indicated TYPE. */
84 static tree dfs_check_overlap (tree, void *);
85 static tree dfs_no_overlap_yet (tree, int, void *);
86 static base_kind lookup_base_r (tree, tree, base_access, bool, tree *);
87 static int dynamic_cast_base_recurse (tree, tree, bool, tree *);
88 static tree marked_pushdecls_p (tree, int, void *);
89 static tree unmarked_pushdecls_p (tree, int, void *);
90 static tree dfs_debug_unmarkedp (tree, int, void *);
91 static tree dfs_debug_mark (tree, void *);
92 static tree dfs_push_type_decls (tree, void *);
93 static tree dfs_push_decls (tree, void *);
94 static tree dfs_unuse_fields (tree, void *);
95 static tree add_conversions (tree, void *);
96 static int look_for_overrides_r (tree, tree);
97 static struct search_level *push_search_level (struct stack_level *,
99 static struct search_level *pop_search_level (struct stack_level *);
100 static tree bfs_walk (tree, tree (*) (tree, void *),
101 tree (*) (tree, int, void *), void *);
102 static tree lookup_field_queue_p (tree, int, void *);
103 static int shared_member_p (tree);
104 static tree lookup_field_r (tree, void *);
105 static tree dfs_accessible_queue_p (tree, int, void *);
106 static tree dfs_accessible_p (tree, void *);
107 static tree dfs_access_in_type (tree, void *);
108 static access_kind access_in_type (tree, tree);
109 static int protected_accessible_p (tree, tree, tree);
110 static int friend_accessible_p (tree, tree, tree);
111 static void setup_class_bindings (tree, int);
112 static int template_self_reference_p (tree, tree);
113 static tree dfs_get_pure_virtuals (tree, void *);
115 /* Allocate a level of searching. */
117 static struct search_level *
118 push_search_level (struct stack_level *stack, struct obstack *obstack)
120 struct search_level tem;
123 return push_stack_level (obstack, (char *)&tem, sizeof (tem));
126 /* Discard a level of search allocation. */
128 static struct search_level *
129 pop_search_level (struct stack_level *obstack)
131 register struct search_level *stack = pop_stack_level (obstack);
136 /* Variables for gathering statistics. */
137 #ifdef GATHER_STATISTICS
138 static int n_fields_searched;
139 static int n_calls_lookup_field, n_calls_lookup_field_1;
140 static int n_calls_lookup_fnfields, n_calls_lookup_fnfields_1;
141 static int n_calls_get_base_type;
142 static int n_outer_fields_searched;
143 static int n_contexts_saved;
144 #endif /* GATHER_STATISTICS */
147 /* Worker for lookup_base. BINFO is the binfo we are searching at,
148 BASE is the RECORD_TYPE we are searching for. ACCESS is the
149 required access checks. IS_VIRTUAL indicates if BINFO is morally
152 If BINFO is of the required type, then *BINFO_PTR is examined to
153 compare with any other instance of BASE we might have already
154 discovered. *BINFO_PTR is initialized and a base_kind return value
155 indicates what kind of base was located.
157 Otherwise BINFO's bases are searched. */
160 lookup_base_r (tree binfo, tree base, base_access access,
161 bool is_virtual, /* inside a virtual part */
165 tree bases, accesses;
166 base_kind found = bk_not_base;
168 if (same_type_p (BINFO_TYPE (binfo), base))
170 /* We have found a base. Check against what we have found
172 found = bk_same_type;
174 found = bk_via_virtual;
178 else if (binfo != *binfo_ptr)
180 if (access != ba_any)
182 else if (!is_virtual)
183 /* Prefer a non-virtual base. */
191 bases = BINFO_BASETYPES (binfo);
192 accesses = BINFO_BASEACCESSES (binfo);
196 for (i = TREE_VEC_LENGTH (bases); i--;)
198 tree base_binfo = TREE_VEC_ELT (bases, i);
201 bk = lookup_base_r (base_binfo, base,
203 is_virtual || TREE_VIA_VIRTUAL (base_binfo),
209 if (access != ba_any)
218 my_friendly_assert (found == bk_not_base, 20010723);
223 if (found != bk_ambig)
237 /* Lookup BASE in the hierarchy dominated by T. Do access checking as
238 ACCESS specifies. Return the binfo we discover. If KIND_PTR is
239 non-NULL, fill with information about what kind of base we
242 If the base is inaccessible, or ambiguous, and the ba_quiet bit is
243 not set in ACCESS, then an error is issued and error_mark_node is
244 returned. If the ba_quiet bit is set, then no error is issued and
245 NULL_TREE is returned. */
248 lookup_base (tree t, tree base, base_access access, base_kind *kind_ptr)
250 tree binfo = NULL; /* The binfo we've found so far. */
254 if (t == error_mark_node || base == error_mark_node)
257 *kind_ptr = bk_not_base;
258 return error_mark_node;
260 my_friendly_assert (TYPE_P (base), 20011127);
268 t_binfo = TYPE_BINFO (t);
270 /* Ensure that the types are instantiated. */
271 t = complete_type (TYPE_MAIN_VARIANT (t));
272 base = complete_type (TYPE_MAIN_VARIANT (base));
274 bk = lookup_base_r (t_binfo, base, access, 0, &binfo);
276 /* Check that the base is unambiguous and accessible. */
277 if (access != ba_any)
285 if (!(access & ba_quiet))
287 error ("`%T' is an ambiguous base of `%T'", base, t);
288 binfo = error_mark_node;
293 if (access != ba_ignore
294 /* If BASE is incomplete, then BASE and TYPE are probably
295 the same, in which case BASE is accessible. If they
296 are not the same, then TYPE is invalid. In that case,
297 there's no need to issue another error here, and
298 there's no implicit typedef to use in the code that
299 follows, so we skip the check. */
300 && COMPLETE_TYPE_P (base))
304 /* [class.access.base]
306 A base class is said to be accessible if an invented public
307 member of the base class is accessible. */
308 /* Rather than inventing a public member, we use the implicit
309 public typedef created in the scope of every class. */
310 decl = TYPE_FIELDS (base);
311 while (TREE_CODE (decl) != TYPE_DECL
312 || !DECL_ARTIFICIAL (decl)
313 || DECL_NAME (decl) != constructor_name (base))
314 decl = TREE_CHAIN (decl);
315 while (ANON_AGGR_TYPE_P (t))
316 t = TYPE_CONTEXT (t);
317 if (!accessible_p (t, decl))
319 if (!(access & ba_quiet))
321 error ("`%T' is an inaccessible base of `%T'", base, t);
322 binfo = error_mark_node;
326 bk = bk_inaccessible;
338 /* Worker function for get_dynamic_cast_base_type. */
341 dynamic_cast_base_recurse (tree subtype, tree binfo, bool is_via_virtual,
344 tree binfos, accesses;
348 if (BINFO_TYPE (binfo) == subtype)
354 *offset_ptr = BINFO_OFFSET (binfo);
359 binfos = BINFO_BASETYPES (binfo);
360 accesses = BINFO_BASEACCESSES (binfo);
361 n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0;
362 for (i = 0; i < n_baselinks; i++)
364 tree base_binfo = TREE_VEC_ELT (binfos, i);
365 tree base_access = TREE_VEC_ELT (accesses, i);
368 if (base_access != access_public_node)
370 rval = dynamic_cast_base_recurse
371 (subtype, base_binfo,
372 is_via_virtual || TREE_VIA_VIRTUAL (base_binfo), offset_ptr);
376 worst = worst >= 0 ? -3 : worst;
379 else if (rval == -3 && worst != -1)
385 /* The dynamic cast runtime needs a hint about how the static SUBTYPE type
386 started from is related to the required TARGET type, in order to optimize
387 the inheritance graph search. This information is independent of the
388 current context, and ignores private paths, hence get_base_distance is
389 inappropriate. Return a TREE specifying the base offset, BOFF.
390 BOFF >= 0, there is only one public non-virtual SUBTYPE base at offset BOFF,
391 and there are no public virtual SUBTYPE bases.
392 BOFF == -1, SUBTYPE occurs as multiple public virtual or non-virtual bases.
393 BOFF == -2, SUBTYPE is not a public base.
394 BOFF == -3, SUBTYPE occurs as multiple public non-virtual bases. */
397 get_dynamic_cast_base_type (tree subtype, tree target)
399 tree offset = NULL_TREE;
400 int boff = dynamic_cast_base_recurse (subtype, TYPE_BINFO (target),
405 offset = build_int_2 (boff, -1);
406 TREE_TYPE (offset) = ssizetype;
410 /* Search for a member with name NAME in a multiple inheritance
411 lattice specified by TYPE. If it does not exist, return NULL_TREE.
412 If the member is ambiguously referenced, return `error_mark_node'.
413 Otherwise, return a DECL with the indicated name. If WANT_TYPE is
414 true, type declarations are preferred. */
416 /* Do a 1-level search for NAME as a member of TYPE. The caller must
417 figure out whether it can access this field. (Since it is only one
418 level, this is reasonable.) */
421 lookup_field_1 (tree type, tree name, bool want_type)
425 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
426 || TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM
427 || TREE_CODE (type) == TYPENAME_TYPE)
428 /* The TYPE_FIELDS of a TEMPLATE_TYPE_PARM and
429 BOUND_TEMPLATE_TEMPLATE_PARM are not fields at all;
430 instead TYPE_FIELDS is the TEMPLATE_PARM_INDEX. (Miraculously,
431 the code often worked even when we treated the index as a list
433 The TYPE_FIELDS of TYPENAME_TYPE is its TYPENAME_TYPE_FULLNAME. */
437 && DECL_LANG_SPECIFIC (TYPE_NAME (type))
438 && DECL_SORTED_FIELDS (TYPE_NAME (type)))
440 tree *fields = &TREE_VEC_ELT (DECL_SORTED_FIELDS (TYPE_NAME (type)), 0);
441 int lo = 0, hi = TREE_VEC_LENGTH (DECL_SORTED_FIELDS (TYPE_NAME (type)));
448 #ifdef GATHER_STATISTICS
450 #endif /* GATHER_STATISTICS */
452 if (DECL_NAME (fields[i]) > name)
454 else if (DECL_NAME (fields[i]) < name)
460 /* We might have a nested class and a field with the
461 same name; we sorted them appropriately via
462 field_decl_cmp, so just look for the first or last
463 field with this name. */
468 while (i >= lo && DECL_NAME (fields[i]) == name);
469 if (TREE_CODE (field) != TYPE_DECL
470 && !DECL_CLASS_TEMPLATE_P (field))
477 while (i < hi && DECL_NAME (fields[i]) == name);
485 field = TYPE_FIELDS (type);
487 #ifdef GATHER_STATISTICS
488 n_calls_lookup_field_1++;
489 #endif /* GATHER_STATISTICS */
490 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
492 #ifdef GATHER_STATISTICS
494 #endif /* GATHER_STATISTICS */
495 my_friendly_assert (DECL_P (field), 0);
496 if (DECL_NAME (field) == NULL_TREE
497 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
499 tree temp = lookup_field_1 (TREE_TYPE (field), name, want_type);
503 if (TREE_CODE (field) == USING_DECL)
504 /* For now, we're just treating member using declarations as
505 old ARM-style access declarations. Thus, there's no reason
506 to return a USING_DECL, and the rest of the compiler can't
507 handle it. Once the class is defined, these are purged
508 from TYPE_FIELDS anyhow; see handle_using_decl. */
511 if (DECL_NAME (field) == name
513 || TREE_CODE (field) == TYPE_DECL
514 || DECL_CLASS_TEMPLATE_P (field)))
518 if (name == vptr_identifier)
520 /* Give the user what s/he thinks s/he wants. */
521 if (TYPE_POLYMORPHIC_P (type))
522 return TYPE_VFIELD (type);
527 /* There are a number of cases we need to be aware of here:
528 current_class_type current_function_decl
535 Those last two make life interesting. If we're in a function which is
536 itself inside a class, we need decls to go into the fn's decls (our
537 second case below). But if we're in a class and the class itself is
538 inside a function, we need decls to go into the decls for the class. To
539 achieve this last goal, we must see if, when both current_class_ptr and
540 current_function_decl are set, the class was declared inside that
541 function. If so, we know to put the decls into the class's scope. */
546 if (current_function_decl == NULL_TREE)
547 return current_class_type;
548 if (current_class_type == NULL_TREE)
549 return current_function_decl;
550 if ((DECL_FUNCTION_MEMBER_P (current_function_decl)
551 && same_type_p (DECL_CONTEXT (current_function_decl),
553 || (DECL_FRIEND_CONTEXT (current_function_decl)
554 && same_type_p (DECL_FRIEND_CONTEXT (current_function_decl),
555 current_class_type)))
556 return current_function_decl;
558 return current_class_type;
561 /* Returns nonzero if we are currently in a function scope. Note
562 that this function returns zero if we are within a local class, but
563 not within a member function body of the local class. */
566 at_function_scope_p ()
568 tree cs = current_scope ();
569 return cs && TREE_CODE (cs) == FUNCTION_DECL;
572 /* Returns true if the innermost active scope is a class scope. */
577 tree cs = current_scope ();
578 return cs && TYPE_P (cs);
581 /* Return the scope of DECL, as appropriate when doing name-lookup. */
584 context_for_name_lookup (tree decl)
588 For the purposes of name lookup, after the anonymous union
589 definition, the members of the anonymous union are considered to
590 have been defined in the scope in which the anonymous union is
592 tree context = DECL_CONTEXT (decl);
594 while (context && TYPE_P (context) && ANON_AGGR_TYPE_P (context))
595 context = TYPE_CONTEXT (context);
597 context = global_namespace;
602 /* The accessibility routines use BINFO_ACCESS for scratch space
603 during the computation of the accssibility of some declaration. */
605 #define BINFO_ACCESS(NODE) \
606 ((access_kind) ((TREE_PUBLIC (NODE) << 1) | TREE_PRIVATE (NODE)))
608 /* Set the access associated with NODE to ACCESS. */
610 #define SET_BINFO_ACCESS(NODE, ACCESS) \
611 ((TREE_PUBLIC (NODE) = ((ACCESS) & 2) != 0), \
612 (TREE_PRIVATE (NODE) = ((ACCESS) & 1) != 0))
614 /* Called from access_in_type via dfs_walk. Calculate the access to
615 DATA (which is really a DECL) in BINFO. */
618 dfs_access_in_type (tree binfo, void *data)
620 tree decl = (tree) data;
621 tree type = BINFO_TYPE (binfo);
622 access_kind access = ak_none;
624 if (context_for_name_lookup (decl) == type)
626 /* If we have desceneded to the scope of DECL, just note the
627 appropriate access. */
628 if (TREE_PRIVATE (decl))
630 else if (TREE_PROTECTED (decl))
631 access = ak_protected;
637 /* First, check for an access-declaration that gives us more
638 access to the DECL. The CONST_DECL for an enumeration
639 constant will not have DECL_LANG_SPECIFIC, and thus no
641 if (DECL_LANG_SPECIFIC (decl) && !DECL_DISCRIMINATOR_P (decl))
643 tree decl_access = purpose_member (type, DECL_ACCESS (decl));
647 decl_access = TREE_VALUE (decl_access);
649 if (decl_access == access_public_node)
651 else if (decl_access == access_protected_node)
652 access = ak_protected;
653 else if (decl_access == access_private_node)
656 my_friendly_assert (false, 20030217);
664 tree binfos, accesses;
666 /* Otherwise, scan our baseclasses, and pick the most favorable
668 binfos = BINFO_BASETYPES (binfo);
669 accesses = BINFO_BASEACCESSES (binfo);
670 n_baselinks = binfos ? TREE_VEC_LENGTH (binfos) : 0;
671 for (i = 0; i < n_baselinks; ++i)
673 tree base_binfo = TREE_VEC_ELT (binfos, i);
674 tree base_access = TREE_VEC_ELT (accesses, i);
675 access_kind base_access_now = BINFO_ACCESS (base_binfo);
677 if (base_access_now == ak_none || base_access_now == ak_private)
678 /* If it was not accessible in the base, or only
679 accessible as a private member, we can't access it
681 base_access_now = ak_none;
682 else if (base_access == access_protected_node)
683 /* Public and protected members in the base become
685 base_access_now = ak_protected;
686 else if (base_access == access_private_node)
687 /* Public and protected members in the base become
689 base_access_now = ak_private;
691 /* See if the new access, via this base, gives more
692 access than our previous best access. */
693 if (base_access_now != ak_none
694 && (access == ak_none || base_access_now < access))
696 access = base_access_now;
698 /* If the new access is public, we can't do better. */
699 if (access == ak_public)
706 /* Note the access to DECL in TYPE. */
707 SET_BINFO_ACCESS (binfo, access);
709 /* Mark TYPE as visited so that if we reach it again we do not
710 duplicate our efforts here. */
711 BINFO_MARKED (binfo) = 1;
716 /* Return the access to DECL in TYPE. */
719 access_in_type (tree type, tree decl)
721 tree binfo = TYPE_BINFO (type);
723 /* We must take into account
727 If a name can be reached by several paths through a multiple
728 inheritance graph, the access is that of the path that gives
731 The algorithm we use is to make a post-order depth-first traversal
732 of the base-class hierarchy. As we come up the tree, we annotate
733 each node with the most lenient access. */
734 dfs_walk_real (binfo, 0, dfs_access_in_type, unmarkedp, decl);
735 dfs_walk (binfo, dfs_unmark, markedp, 0);
737 return BINFO_ACCESS (binfo);
740 /* Called from dfs_accessible_p via dfs_walk. */
743 dfs_accessible_queue_p (tree derived, int ix, void *data ATTRIBUTE_UNUSED)
745 tree binfo = BINFO_BASETYPE (derived, ix);
747 if (BINFO_MARKED (binfo))
750 /* If this class is inherited via private or protected inheritance,
751 then we can't see it, unless we are a friend of the derived class. */
752 if (BINFO_BASEACCESS (derived, ix) != access_public_node
753 && !is_friend (BINFO_TYPE (derived), current_scope ()))
759 /* Called from dfs_accessible_p via dfs_walk. */
762 dfs_accessible_p (tree binfo, void *data)
764 int protected_ok = data != 0;
767 BINFO_MARKED (binfo) = 1;
768 access = BINFO_ACCESS (binfo);
769 if (access == ak_public || (access == ak_protected && protected_ok))
771 else if (access != ak_none
772 && is_friend (BINFO_TYPE (binfo), current_scope ()))
778 /* Returns nonzero if it is OK to access DECL through an object
779 indicated by BINFO in the context of DERIVED. */
782 protected_accessible_p (tree decl, tree derived, tree binfo)
786 /* We're checking this clause from [class.access.base]
788 m as a member of N is protected, and the reference occurs in a
789 member or friend of class N, or in a member or friend of a
790 class P derived from N, where m as a member of P is private or
793 Here DERIVED is a possible P and DECL is m. accessible_p will
794 iterate over various values of N, but the access to m in DERIVED
797 Note that I believe that the passage above is wrong, and should read
798 "...is private or protected or public"; otherwise you get bizarre results
799 whereby a public using-decl can prevent you from accessing a protected
800 member of a base. (jason 2000/02/28) */
802 /* If DERIVED isn't derived from m's class, then it can't be a P. */
803 if (!DERIVED_FROM_P (context_for_name_lookup (decl), derived))
806 access = access_in_type (derived, decl);
808 /* If m is inaccessible in DERIVED, then it's not a P. */
809 if (access == ak_none)
814 When a friend or a member function of a derived class references
815 a protected nonstatic member of a base class, an access check
816 applies in addition to those described earlier in clause
817 _class.access_) Except when forming a pointer to member
818 (_expr.unary.op_), the access must be through a pointer to,
819 reference to, or object of the derived class itself (or any class
820 derived from that class) (_expr.ref_). If the access is to form
821 a pointer to member, the nested-name-specifier shall name the
822 derived class (or any class derived from that class). */
823 if (DECL_NONSTATIC_MEMBER_P (decl))
825 /* We can tell through what the reference is occurring by
826 chasing BINFO up to the root. */
828 while (BINFO_INHERITANCE_CHAIN (t))
829 t = BINFO_INHERITANCE_CHAIN (t);
831 if (!DERIVED_FROM_P (derived, BINFO_TYPE (t)))
838 /* Returns nonzero if SCOPE is a friend of a type which would be able
839 to access DECL through the object indicated by BINFO. */
842 friend_accessible_p (tree scope, tree decl, tree binfo)
844 tree befriending_classes;
850 if (TREE_CODE (scope) == FUNCTION_DECL
851 || DECL_FUNCTION_TEMPLATE_P (scope))
852 befriending_classes = DECL_BEFRIENDING_CLASSES (scope);
853 else if (TYPE_P (scope))
854 befriending_classes = CLASSTYPE_BEFRIENDING_CLASSES (scope);
858 for (t = befriending_classes; t; t = TREE_CHAIN (t))
859 if (protected_accessible_p (decl, TREE_VALUE (t), binfo))
862 /* Nested classes are implicitly friends of their enclosing types, as
863 per core issue 45 (this is a change from the standard). */
865 for (t = TYPE_CONTEXT (scope); t && TYPE_P (t); t = TYPE_CONTEXT (t))
866 if (protected_accessible_p (decl, t, binfo))
869 if (TREE_CODE (scope) == FUNCTION_DECL
870 || DECL_FUNCTION_TEMPLATE_P (scope))
872 /* Perhaps this SCOPE is a member of a class which is a
874 if (DECL_CLASS_SCOPE_P (decl)
875 && friend_accessible_p (DECL_CONTEXT (scope), decl, binfo))
878 /* Or an instantiation of something which is a friend. */
879 if (DECL_TEMPLATE_INFO (scope))
880 return friend_accessible_p (DECL_TI_TEMPLATE (scope), decl, binfo);
882 else if (CLASSTYPE_TEMPLATE_INFO (scope))
883 return friend_accessible_p (CLASSTYPE_TI_TEMPLATE (scope), decl, binfo);
888 /* DECL is a declaration from a base class of TYPE, which was the
889 class used to name DECL. Return nonzero if, in the current
890 context, DECL is accessible. If TYPE is actually a BINFO node,
891 then we can tell in what context the access is occurring by looking
892 at the most derived class along the path indicated by BINFO. */
895 accessible_p (tree type, tree decl)
900 /* Nonzero if it's OK to access DECL if it has protected
901 accessibility in TYPE. */
902 int protected_ok = 0;
904 /* If this declaration is in a block or namespace scope, there's no
906 if (!TYPE_P (context_for_name_lookup (decl)))
912 type = BINFO_TYPE (type);
915 binfo = TYPE_BINFO (type);
917 /* [class.access.base]
919 A member m is accessible when named in class N if
921 --m as a member of N is public, or
923 --m as a member of N is private, and the reference occurs in a
924 member or friend of class N, or
926 --m as a member of N is protected, and the reference occurs in a
927 member or friend of class N, or in a member or friend of a
928 class P derived from N, where m as a member of P is private or
931 --there exists a base class B of N that is accessible at the point
932 of reference, and m is accessible when named in class B.
934 We walk the base class hierarchy, checking these conditions. */
936 /* Figure out where the reference is occurring. Check to see if
937 DECL is private or protected in this scope, since that will
938 determine whether protected access is allowed. */
939 if (current_class_type)
940 protected_ok = protected_accessible_p (decl, current_class_type, binfo);
942 /* Now, loop through the classes of which we are a friend. */
944 protected_ok = friend_accessible_p (current_scope (), decl, binfo);
946 /* Standardize the binfo that access_in_type will use. We don't
947 need to know what path was chosen from this point onwards. */
948 binfo = TYPE_BINFO (type);
950 /* Compute the accessibility of DECL in the class hierarchy
951 dominated by type. */
952 access_in_type (type, decl);
953 /* Walk the hierarchy again, looking for a base class that allows
955 t = dfs_walk (binfo, dfs_accessible_p,
956 dfs_accessible_queue_p,
957 protected_ok ? &protected_ok : 0);
958 /* Clear any mark bits. Note that we have to walk the whole tree
959 here, since we have aborted the previous walk from some point
961 dfs_walk (binfo, dfs_unmark, 0, 0);
963 return t != NULL_TREE;
966 struct lookup_field_info {
967 /* The type in which we're looking. */
969 /* The name of the field for which we're looking. */
971 /* If non-NULL, the current result of the lookup. */
973 /* The path to RVAL. */
975 /* If non-NULL, the lookup was ambiguous, and this is a list of the
978 /* If nonzero, we are looking for types, not data members. */
980 /* If something went wrong, a message indicating what. */
984 /* Returns nonzero if BINFO is not hidden by the value found by the
985 lookup so far. If BINFO is hidden, then there's no need to look in
986 it. DATA is really a struct lookup_field_info. Called from
987 lookup_field via breadth_first_search. */
990 lookup_field_queue_p (tree derived, int ix, void *data)
992 tree binfo = BINFO_BASETYPE (derived, ix);
993 struct lookup_field_info *lfi = (struct lookup_field_info *) data;
995 /* Don't look for constructors or destructors in base classes. */
996 if (IDENTIFIER_CTOR_OR_DTOR_P (lfi->name))
999 /* If this base class is hidden by the best-known value so far, we
1000 don't need to look. */
1001 if (lfi->rval_binfo && original_binfo (binfo, lfi->rval_binfo))
1004 /* If this is a dependent base, don't look in it. */
1005 if (BINFO_DEPENDENT_BASE_P (binfo))
1011 /* Within the scope of a template class, you can refer to the to the
1012 current specialization with the name of the template itself. For
1015 template <typename T> struct S { S* sp; }
1017 Returns nonzero if DECL is such a declaration in a class TYPE. */
1020 template_self_reference_p (tree type, tree decl)
1022 return (CLASSTYPE_USE_TEMPLATE (type)
1023 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type))
1024 && TREE_CODE (decl) == TYPE_DECL
1025 && DECL_ARTIFICIAL (decl)
1026 && DECL_NAME (decl) == constructor_name (type));
1030 /* Nonzero for a class member means that it is shared between all objects
1033 [class.member.lookup]:If the resulting set of declarations are not all
1034 from sub-objects of the same type, or the set has a nonstatic member
1035 and includes members from distinct sub-objects, there is an ambiguity
1036 and the program is ill-formed.
1038 This function checks that T contains no nonstatic members. */
1041 shared_member_p (tree t)
1043 if (TREE_CODE (t) == VAR_DECL || TREE_CODE (t) == TYPE_DECL \
1044 || TREE_CODE (t) == CONST_DECL)
1046 if (is_overloaded_fn (t))
1048 for (; t; t = OVL_NEXT (t))
1050 tree fn = OVL_CURRENT (t);
1051 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
1059 /* DATA is really a struct lookup_field_info. Look for a field with
1060 the name indicated there in BINFO. If this function returns a
1061 non-NULL value it is the result of the lookup. Called from
1062 lookup_field via breadth_first_search. */
1065 lookup_field_r (tree binfo, void *data)
1067 struct lookup_field_info *lfi = (struct lookup_field_info *) data;
1068 tree type = BINFO_TYPE (binfo);
1069 tree nval = NULL_TREE;
1071 /* First, look for a function. There can't be a function and a data
1072 member with the same name, and if there's a function and a type
1073 with the same name, the type is hidden by the function. */
1074 if (!lfi->want_type)
1076 int idx = lookup_fnfields_1 (type, lfi->name);
1078 nval = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (type), idx);
1082 /* Look for a data member or type. */
1083 nval = lookup_field_1 (type, lfi->name, lfi->want_type);
1085 /* If there is no declaration with the indicated name in this type,
1086 then there's nothing to do. */
1090 /* If we're looking up a type (as with an elaborated type specifier)
1091 we ignore all non-types we find. */
1092 if (lfi->want_type && TREE_CODE (nval) != TYPE_DECL
1093 && !DECL_CLASS_TEMPLATE_P (nval))
1095 if (lfi->name == TYPE_IDENTIFIER (type))
1097 /* If the aggregate has no user defined constructors, we allow
1098 it to have fields with the same name as the enclosing type.
1099 If we are looking for that name, find the corresponding
1101 for (nval = TREE_CHAIN (nval); nval; nval = TREE_CHAIN (nval))
1102 if (DECL_NAME (nval) == lfi->name
1103 && TREE_CODE (nval) == TYPE_DECL)
1108 if (!nval && CLASSTYPE_NESTED_UTDS (type) != NULL)
1110 binding_entry e = binding_table_find (CLASSTYPE_NESTED_UTDS (type),
1113 nval = TYPE_MAIN_DECL (e->type);
1119 /* You must name a template base class with a template-id. */
1120 if (!same_type_p (type, lfi->type)
1121 && template_self_reference_p (type, nval))
1124 /* If the lookup already found a match, and the new value doesn't
1125 hide the old one, we might have an ambiguity. */
1126 if (lfi->rval_binfo && !original_binfo (lfi->rval_binfo, binfo))
1128 if (nval == lfi->rval && shared_member_p (nval))
1129 /* The two things are really the same. */
1131 else if (original_binfo (binfo, lfi->rval_binfo))
1132 /* The previous value hides the new one. */
1136 /* We have a real ambiguity. We keep a chain of all the
1138 if (!lfi->ambiguous && lfi->rval)
1140 /* This is the first time we noticed an ambiguity. Add
1141 what we previously thought was a reasonable candidate
1143 lfi->ambiguous = tree_cons (NULL_TREE, lfi->rval, NULL_TREE);
1144 TREE_TYPE (lfi->ambiguous) = error_mark_node;
1147 /* Add the new value. */
1148 lfi->ambiguous = tree_cons (NULL_TREE, nval, lfi->ambiguous);
1149 TREE_TYPE (lfi->ambiguous) = error_mark_node;
1150 lfi->errstr = "request for member `%D' is ambiguous";
1156 lfi->rval_binfo = binfo;
1162 /* Return a "baselink" which BASELINK_BINFO, BASELINK_ACCESS_BINFO,
1163 BASELINK_FUNCTIONS, and BASELINK_OPTYPE set to BINFO, ACCESS_BINFO,
1164 FUNCTIONS, and OPTYPE respectively. */
1167 build_baselink (tree binfo, tree access_binfo, tree functions, tree optype)
1171 my_friendly_assert (TREE_CODE (functions) == FUNCTION_DECL
1172 || TREE_CODE (functions) == TEMPLATE_DECL
1173 || TREE_CODE (functions) == TEMPLATE_ID_EXPR
1174 || TREE_CODE (functions) == OVERLOAD,
1176 my_friendly_assert (!optype || TYPE_P (optype), 20020730);
1177 my_friendly_assert (TREE_TYPE (functions), 20020805);
1179 baselink = make_node (BASELINK);
1180 TREE_TYPE (baselink) = TREE_TYPE (functions);
1181 BASELINK_BINFO (baselink) = binfo;
1182 BASELINK_ACCESS_BINFO (baselink) = access_binfo;
1183 BASELINK_FUNCTIONS (baselink) = functions;
1184 BASELINK_OPTYPE (baselink) = optype;
1189 /* Look for a member named NAME in an inheritance lattice dominated by
1190 XBASETYPE. If PROTECT is 0 or two, we do not check access. If it
1191 is 1, we enforce accessibility. If PROTECT is zero, then, for an
1192 ambiguous lookup, we return NULL. If PROTECT is 1, we issue error
1193 messages about inaccessible or ambiguous lookup. If PROTECT is 2,
1194 we return a TREE_LIST whose TREE_TYPE is error_mark_node and whose
1195 TREE_VALUEs are the list of ambiguous candidates.
1197 WANT_TYPE is 1 when we should only return TYPE_DECLs.
1199 If nothing can be found return NULL_TREE and do not issue an error. */
1202 lookup_member (tree xbasetype, tree name, int protect, bool want_type)
1204 tree rval, rval_binfo = NULL_TREE;
1205 tree type = NULL_TREE, basetype_path = NULL_TREE;
1206 struct lookup_field_info lfi;
1208 /* rval_binfo is the binfo associated with the found member, note,
1209 this can be set with useful information, even when rval is not
1210 set, because it must deal with ALL members, not just non-function
1211 members. It is used for ambiguity checking and the hidden
1212 checks. Whereas rval is only set if a proper (not hidden)
1213 non-function member is found. */
1215 const char *errstr = 0;
1217 my_friendly_assert (TREE_CODE (name) == IDENTIFIER_NODE, 20030624);
1219 if (TREE_CODE (xbasetype) == TREE_VEC)
1221 type = BINFO_TYPE (xbasetype);
1222 basetype_path = xbasetype;
1226 my_friendly_assert (IS_AGGR_TYPE_CODE (TREE_CODE (xbasetype)), 20030624);
1228 basetype_path = TYPE_BINFO (type);
1229 my_friendly_assert (!BINFO_INHERITANCE_CHAIN (basetype_path), 980827);
1232 if (type == current_class_type && TYPE_BEING_DEFINED (type)
1233 && IDENTIFIER_CLASS_VALUE (name))
1235 tree field = IDENTIFIER_CLASS_VALUE (name);
1236 if (! is_overloaded_fn (field)
1237 && ! (want_type && TREE_CODE (field) != TYPE_DECL))
1238 /* We're in the scope of this class, and the value has already
1239 been looked up. Just return the cached value. */
1243 complete_type (type);
1245 #ifdef GATHER_STATISTICS
1246 n_calls_lookup_field++;
1247 #endif /* GATHER_STATISTICS */
1249 memset (&lfi, 0, sizeof (lfi));
1252 lfi.want_type = want_type;
1253 bfs_walk (basetype_path, &lookup_field_r, &lookup_field_queue_p, &lfi);
1255 rval_binfo = lfi.rval_binfo;
1257 type = BINFO_TYPE (rval_binfo);
1258 errstr = lfi.errstr;
1260 /* If we are not interested in ambiguities, don't report them;
1261 just return NULL_TREE. */
1262 if (!protect && lfi.ambiguous)
1268 return lfi.ambiguous;
1275 In the case of overloaded function names, access control is
1276 applied to the function selected by overloaded resolution. */
1277 if (rval && protect && !is_overloaded_fn (rval))
1278 perform_or_defer_access_check (basetype_path, rval);
1280 if (errstr && protect)
1282 error (errstr, name, type);
1284 print_candidates (lfi.ambiguous);
1285 rval = error_mark_node;
1288 if (rval && is_overloaded_fn (rval))
1289 rval = build_baselink (rval_binfo, basetype_path, rval,
1290 (IDENTIFIER_TYPENAME_P (name)
1291 ? TREE_TYPE (name): NULL_TREE));
1295 /* Like lookup_member, except that if we find a function member we
1296 return NULL_TREE. */
1299 lookup_field (tree xbasetype, tree name, int protect, bool want_type)
1301 tree rval = lookup_member (xbasetype, name, protect, want_type);
1303 /* Ignore functions. */
1304 if (rval && BASELINK_P (rval))
1310 /* Like lookup_member, except that if we find a non-function member we
1311 return NULL_TREE. */
1314 lookup_fnfields (tree xbasetype, tree name, int protect)
1316 tree rval = lookup_member (xbasetype, name, protect, /*want_type=*/false);
1318 /* Ignore non-functions. */
1319 if (rval && !BASELINK_P (rval))
1325 /* Return the index in the CLASSTYPE_METHOD_VEC for CLASS_TYPE
1326 corresponding to "operator TYPE ()", or -1 if there is no such
1327 operator. Only CLASS_TYPE itself is searched; this routine does
1328 not scan the base classes of CLASS_TYPE. */
1331 lookup_conversion_operator (tree class_type, tree type)
1336 tree methods = CLASSTYPE_METHOD_VEC (class_type);
1338 for (pass = 0; pass < 2; ++pass)
1339 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
1340 i < TREE_VEC_LENGTH (methods);
1343 tree fn = TREE_VEC_ELT (methods, i);
1344 /* The size of the vector may have some unused slots at the
1349 /* All the conversion operators come near the beginning of the
1350 class. Therefore, if FN is not a conversion operator, there
1351 is no matching conversion operator in CLASS_TYPE. */
1352 fn = OVL_CURRENT (fn);
1353 if (!DECL_CONV_FN_P (fn))
1358 /* On the first pass we only consider exact matches. If
1359 the types match, this slot is the one where the right
1360 conversion operators can be found. */
1361 if (TREE_CODE (fn) != TEMPLATE_DECL
1362 && same_type_p (DECL_CONV_FN_TYPE (fn), type))
1367 /* On the second pass we look for template conversion
1368 operators. It may be possible to instantiate the
1369 template to get the type desired. All of the template
1370 conversion operators share a slot. By looking for
1371 templates second we ensure that specializations are
1372 preferred over templates. */
1373 if (TREE_CODE (fn) == TEMPLATE_DECL)
1381 /* TYPE is a class type. Return the index of the fields within
1382 the method vector with name NAME, or -1 is no such field exists. */
1385 lookup_fnfields_1 (tree type, tree name)
1393 if (!CLASS_TYPE_P (type))
1396 method_vec = CLASSTYPE_METHOD_VEC (type);
1401 methods = &TREE_VEC_ELT (method_vec, 0);
1402 len = TREE_VEC_LENGTH (method_vec);
1404 #ifdef GATHER_STATISTICS
1405 n_calls_lookup_fnfields_1++;
1406 #endif /* GATHER_STATISTICS */
1408 /* Constructors are first... */
1409 if (name == ctor_identifier)
1410 return (methods[CLASSTYPE_CONSTRUCTOR_SLOT]
1411 ? CLASSTYPE_CONSTRUCTOR_SLOT : -1);
1412 /* and destructors are second. */
1413 if (name == dtor_identifier)
1414 return (methods[CLASSTYPE_DESTRUCTOR_SLOT]
1415 ? CLASSTYPE_DESTRUCTOR_SLOT : -1);
1416 if (IDENTIFIER_TYPENAME_P (name))
1417 return lookup_conversion_operator (type, TREE_TYPE (name));
1419 /* Skip the conversion operators. */
1420 i = CLASSTYPE_FIRST_CONVERSION_SLOT;
1421 while (i < len && methods[i] && DECL_CONV_FN_P (OVL_CURRENT (methods[i])))
1424 /* If the type is complete, use binary search. */
1425 if (COMPLETE_TYPE_P (type))
1434 #ifdef GATHER_STATISTICS
1435 n_outer_fields_searched++;
1436 #endif /* GATHER_STATISTICS */
1439 /* This slot may be empty; we allocate more slots than we
1440 need. In that case, the entry we're looking for is
1441 closer to the beginning of the list. */
1443 tmp = DECL_NAME (OVL_CURRENT (tmp));
1444 if (!tmp || tmp > name)
1446 else if (tmp < name)
1453 for (; i < len && methods[i]; ++i)
1455 #ifdef GATHER_STATISTICS
1456 n_outer_fields_searched++;
1457 #endif /* GATHER_STATISTICS */
1459 tmp = OVL_CURRENT (methods[i]);
1460 if (DECL_NAME (tmp) == name)
1467 /* DECL is the result of a qualified name lookup. QUALIFYING_SCOPE is
1468 the class or namespace used to qualify the name. CONTEXT_CLASS is
1469 the class corresponding to the object in which DECL will be used.
1470 Return a possibly modified version of DECL that takes into account
1473 In particular, consider an expression like `B::m' in the context of
1474 a derived class `D'. If `B::m' has been resolved to a BASELINK,
1475 then the most derived class indicated by the BASELINK_BINFO will be
1476 `B', not `D'. This function makes that adjustment. */
1479 adjust_result_of_qualified_name_lookup (tree decl,
1480 tree qualifying_scope,
1483 if (context_class && CLASS_TYPE_P (qualifying_scope)
1484 && DERIVED_FROM_P (qualifying_scope, context_class)
1485 && BASELINK_P (decl))
1489 my_friendly_assert (CLASS_TYPE_P (context_class), 20020808);
1491 /* Look for the QUALIFYING_SCOPE as a base of the CONTEXT_CLASS.
1492 Because we do not yet know which function will be chosen by
1493 overload resolution, we cannot yet check either accessibility
1494 or ambiguity -- in either case, the choice of a static member
1495 function might make the usage valid. */
1496 base = lookup_base (context_class, qualifying_scope,
1497 ba_ignore | ba_quiet, NULL);
1500 BASELINK_ACCESS_BINFO (decl) = base;
1501 BASELINK_BINFO (decl)
1502 = lookup_base (base, BINFO_TYPE (BASELINK_BINFO (decl)),
1503 ba_ignore | ba_quiet,
1512 /* Walk the class hierarchy dominated by TYPE. FN is called for each
1513 type in the hierarchy, in a breadth-first preorder traversal.
1514 If it ever returns a non-NULL value, that value is immediately
1515 returned and the walk is terminated. At each node, FN is passed a
1516 BINFO indicating the path from the currently visited base-class to
1517 TYPE. Before each base-class is walked QFN is called. If the
1518 value returned is nonzero, the base-class is walked; otherwise it
1519 is not. If QFN is NULL, it is treated as a function which always
1520 returns 1. Both FN and QFN are passed the DATA whenever they are
1523 Implementation notes: Uses a circular queue, which starts off on
1524 the stack but gets moved to the malloc arena if it needs to be
1525 enlarged. The underflow and overflow conditions are
1526 indistinguishable except by context: if head == tail and we just
1527 moved the head pointer, the queue is empty, but if we just moved
1528 the tail pointer, the queue is full.
1529 Start with enough room for ten concurrent base classes. That
1530 will be enough for most hierarchies. */
1531 #define BFS_WALK_INITIAL_QUEUE_SIZE 10
1534 bfs_walk (tree binfo,
1535 tree (*fn) (tree, void *),
1536 tree (*qfn) (tree, int, void *),
1539 tree rval = NULL_TREE;
1541 tree bases_initial[BFS_WALK_INITIAL_QUEUE_SIZE];
1542 /* A circular queue of the base classes of BINFO. These will be
1543 built up in breadth-first order, except where QFN prunes the
1546 size_t base_buffer_size = BFS_WALK_INITIAL_QUEUE_SIZE;
1547 tree *base_buffer = bases_initial;
1550 base_buffer[tail++] = binfo;
1552 while (head != tail)
1555 tree binfo = base_buffer[head++];
1556 if (head == base_buffer_size)
1559 /* Is this the one we're looking for? If so, we're done. */
1560 rval = fn (binfo, data);
1564 n_bases = BINFO_N_BASETYPES (binfo);
1565 for (ix = 0; ix != n_bases; ix++)
1570 base_binfo = (*qfn) (binfo, ix, data);
1572 base_binfo = BINFO_BASETYPE (binfo, ix);
1576 base_buffer[tail++] = base_binfo;
1577 if (tail == base_buffer_size)
1581 tree *new_buffer = xmalloc (2 * base_buffer_size
1583 memcpy (&new_buffer[0], &base_buffer[0],
1584 tail * sizeof (tree));
1585 memcpy (&new_buffer[head + base_buffer_size],
1587 (base_buffer_size - head) * sizeof (tree));
1588 if (base_buffer_size != BFS_WALK_INITIAL_QUEUE_SIZE)
1590 base_buffer = new_buffer;
1591 head += base_buffer_size;
1592 base_buffer_size *= 2;
1599 if (base_buffer_size != BFS_WALK_INITIAL_QUEUE_SIZE)
1604 /* Exactly like bfs_walk, except that a depth-first traversal is
1605 performed, and PREFN is called in preorder, while POSTFN is called
1609 dfs_walk_real (tree binfo,
1610 tree (*prefn) (tree, void *),
1611 tree (*postfn) (tree, void *),
1612 tree (*qfn) (tree, int, void *),
1615 tree rval = NULL_TREE;
1617 /* Call the pre-order walking function. */
1620 rval = (*prefn) (binfo, data);
1625 /* Process the basetypes. */
1626 if (BINFO_BASETYPES (binfo))
1628 int i, n = TREE_VEC_LENGTH (BINFO_BASETYPES (binfo));
1629 for (i = 0; i != n; i++)
1634 base_binfo = (*qfn) (binfo, i, data);
1636 base_binfo = BINFO_BASETYPE (binfo, i);
1640 rval = dfs_walk_real (base_binfo, prefn, postfn, qfn, data);
1647 /* Call the post-order walking function. */
1649 rval = (*postfn) (binfo, data);
1654 /* Exactly like bfs_walk, except that a depth-first post-order traversal is
1658 dfs_walk (tree binfo,
1659 tree (*fn) (tree, void *),
1660 tree (*qfn) (tree, int, void *),
1663 return dfs_walk_real (binfo, 0, fn, qfn, data);
1666 /* Check that virtual overrider OVERRIDER is acceptable for base function
1667 BASEFN. Issue diagnostic, and return zero, if unacceptable. */
1670 check_final_overrider (tree overrider, tree basefn)
1672 tree over_type = TREE_TYPE (overrider);
1673 tree base_type = TREE_TYPE (basefn);
1674 tree over_return = TREE_TYPE (over_type);
1675 tree base_return = TREE_TYPE (base_type);
1676 tree over_throw = TYPE_RAISES_EXCEPTIONS (over_type);
1677 tree base_throw = TYPE_RAISES_EXCEPTIONS (base_type);
1680 if (same_type_p (base_return, over_return))
1682 else if ((CLASS_TYPE_P (over_return) && CLASS_TYPE_P (base_return))
1683 || (TREE_CODE (base_return) == TREE_CODE (over_return)
1684 && POINTER_TYPE_P (base_return)))
1686 /* Potentially covariant. */
1687 unsigned base_quals, over_quals;
1689 fail = !POINTER_TYPE_P (base_return);
1692 fail = cp_type_quals (base_return) != cp_type_quals (over_return);
1694 base_return = TREE_TYPE (base_return);
1695 over_return = TREE_TYPE (over_return);
1697 base_quals = cp_type_quals (base_return);
1698 over_quals = cp_type_quals (over_return);
1700 if ((base_quals & over_quals) != over_quals)
1703 if (CLASS_TYPE_P (base_return) && CLASS_TYPE_P (over_return))
1705 tree binfo = lookup_base (over_return, base_return,
1706 ba_check | ba_quiet, NULL);
1712 && can_convert (TREE_TYPE (base_type), TREE_TYPE (over_type)))
1713 /* GNU extension, allow trivial pointer conversions such as
1714 converting to void *, or qualification conversion. */
1716 /* can_convert will permit user defined conversion from a
1717 (reference to) class type. We must reject them. */
1718 over_return = TREE_TYPE (over_type);
1719 if (TREE_CODE (over_return) == REFERENCE_TYPE)
1720 over_return = TREE_TYPE (over_return);
1721 if (CLASS_TYPE_P (over_return))
1731 else if (IDENTIFIER_ERROR_LOCUS (DECL_ASSEMBLER_NAME (overrider)))
1737 cp_error_at ("invalid covariant return type for `%#D'", overrider);
1738 cp_error_at (" overriding `%#D'", basefn);
1742 cp_error_at ("conflicting return type specified for `%#D'",
1744 cp_error_at (" overriding `%#D'", basefn);
1746 SET_IDENTIFIER_ERROR_LOCUS (DECL_ASSEMBLER_NAME (overrider),
1747 DECL_CONTEXT (overrider));
1751 /* Check throw specifier is at least as strict. */
1752 if (!comp_except_specs (base_throw, over_throw, 0))
1754 if (!IDENTIFIER_ERROR_LOCUS (DECL_ASSEMBLER_NAME (overrider)))
1756 cp_error_at ("looser throw specifier for `%#F'", overrider);
1757 cp_error_at (" overriding `%#F'", basefn);
1758 SET_IDENTIFIER_ERROR_LOCUS (DECL_ASSEMBLER_NAME (overrider),
1759 DECL_CONTEXT (overrider));
1767 /* Given a class TYPE, and a function decl FNDECL, look for
1768 virtual functions in TYPE's hierarchy which FNDECL overrides.
1769 We do not look in TYPE itself, only its bases.
1771 Returns nonzero, if we find any. Set FNDECL's DECL_VIRTUAL_P, if we
1772 find that it overrides anything.
1774 We check that every function which is overridden, is correctly
1778 look_for_overrides (tree type, tree fndecl)
1780 tree binfo = TYPE_BINFO (type);
1781 tree basebinfos = BINFO_BASETYPES (binfo);
1782 int nbasebinfos = basebinfos ? TREE_VEC_LENGTH (basebinfos) : 0;
1786 for (ix = 0; ix != nbasebinfos; ix++)
1788 tree basetype = BINFO_TYPE (TREE_VEC_ELT (basebinfos, ix));
1790 if (TYPE_POLYMORPHIC_P (basetype))
1791 found += look_for_overrides_r (basetype, fndecl);
1796 /* Look in TYPE for virtual functions with the same signature as
1800 look_for_overrides_here (tree type, tree fndecl)
1804 if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fndecl))
1805 ix = CLASSTYPE_DESTRUCTOR_SLOT;
1807 ix = lookup_fnfields_1 (type, DECL_NAME (fndecl));
1810 tree fns = TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (type), ix);
1812 for (; fns; fns = OVL_NEXT (fns))
1814 tree fn = OVL_CURRENT (fns);
1816 if (!DECL_VIRTUAL_P (fn))
1817 /* Not a virtual. */;
1818 else if (DECL_CONTEXT (fn) != type)
1819 /* Introduced with a using declaration. */;
1820 else if (DECL_STATIC_FUNCTION_P (fndecl))
1822 tree btypes = TYPE_ARG_TYPES (TREE_TYPE (fn));
1823 tree dtypes = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1824 if (compparms (TREE_CHAIN (btypes), dtypes))
1827 else if (same_signature_p (fndecl, fn))
1834 /* Look in TYPE for virtual functions overridden by FNDECL. Check both
1835 TYPE itself and its bases. */
1838 look_for_overrides_r (tree type, tree fndecl)
1840 tree fn = look_for_overrides_here (type, fndecl);
1843 if (DECL_STATIC_FUNCTION_P (fndecl))
1845 /* A static member function cannot match an inherited
1846 virtual member function. */
1847 cp_error_at ("`%#D' cannot be declared", fndecl);
1848 cp_error_at (" since `%#D' declared in base class", fn);
1852 /* It's definitely virtual, even if not explicitly set. */
1853 DECL_VIRTUAL_P (fndecl) = 1;
1854 check_final_overrider (fndecl, fn);
1859 /* We failed to find one declared in this class. Look in its bases. */
1860 return look_for_overrides (type, fndecl);
1863 /* Called via dfs_walk from dfs_get_pure_virtuals. */
1866 dfs_get_pure_virtuals (tree binfo, void *data)
1868 tree type = (tree) data;
1870 /* We're not interested in primary base classes; the derived class
1871 of which they are a primary base will contain the information we
1873 if (!BINFO_PRIMARY_P (binfo))
1877 for (virtuals = BINFO_VIRTUALS (binfo);
1879 virtuals = TREE_CHAIN (virtuals))
1880 if (DECL_PURE_VIRTUAL_P (BV_FN (virtuals)))
1881 CLASSTYPE_PURE_VIRTUALS (type)
1882 = tree_cons (NULL_TREE, BV_FN (virtuals),
1883 CLASSTYPE_PURE_VIRTUALS (type));
1886 BINFO_MARKED (binfo) = 1;
1891 /* Set CLASSTYPE_PURE_VIRTUALS for TYPE. */
1894 get_pure_virtuals (tree type)
1898 /* Clear the CLASSTYPE_PURE_VIRTUALS list; whatever is already there
1899 is going to be overridden. */
1900 CLASSTYPE_PURE_VIRTUALS (type) = NULL_TREE;
1901 /* Now, run through all the bases which are not primary bases, and
1902 collect the pure virtual functions. We look at the vtable in
1903 each class to determine what pure virtual functions are present.
1904 (A primary base is not interesting because the derived class of
1905 which it is a primary base will contain vtable entries for the
1906 pure virtuals in the base class. */
1907 dfs_walk (TYPE_BINFO (type), dfs_get_pure_virtuals, unmarkedp, type);
1908 dfs_walk (TYPE_BINFO (type), dfs_unmark, markedp, type);
1910 /* Put the pure virtuals in dfs order. */
1911 CLASSTYPE_PURE_VIRTUALS (type) = nreverse (CLASSTYPE_PURE_VIRTUALS (type));
1913 for (vbases = CLASSTYPE_VBASECLASSES (type);
1915 vbases = TREE_CHAIN (vbases))
1919 for (virtuals = BINFO_VIRTUALS (TREE_VALUE (vbases));
1921 virtuals = TREE_CHAIN (virtuals))
1923 tree base_fndecl = BV_FN (virtuals);
1924 if (DECL_NEEDS_FINAL_OVERRIDER_P (base_fndecl))
1925 error ("`%#D' needs a final overrider", base_fndecl);
1930 /* DEPTH-FIRST SEARCH ROUTINES. */
1933 markedp (tree derived, int ix, void *data ATTRIBUTE_UNUSED)
1935 tree binfo = BINFO_BASETYPE (derived, ix);
1937 return BINFO_MARKED (binfo) ? binfo : NULL_TREE;
1941 unmarkedp (tree derived, int ix, void *data ATTRIBUTE_UNUSED)
1943 tree binfo = BINFO_BASETYPE (derived, ix);
1945 return !BINFO_MARKED (binfo) ? binfo : NULL_TREE;
1949 marked_pushdecls_p (tree derived, int ix, void *data ATTRIBUTE_UNUSED)
1951 tree binfo = BINFO_BASETYPE (derived, ix);
1953 return (!BINFO_DEPENDENT_BASE_P (binfo)
1954 && BINFO_PUSHDECLS_MARKED (binfo)) ? binfo : NULL_TREE;
1958 unmarked_pushdecls_p (tree derived, int ix, void *data ATTRIBUTE_UNUSED)
1960 tree binfo = BINFO_BASETYPE (derived, ix);
1962 return (!BINFO_DEPENDENT_BASE_P (binfo)
1963 && !BINFO_PUSHDECLS_MARKED (binfo)) ? binfo : NULL_TREE;
1966 /* The worker functions for `dfs_walk'. These do not need to
1967 test anything (vis a vis marking) if they are paired with
1968 a predicate function (above). */
1971 dfs_unmark (tree binfo, void *data ATTRIBUTE_UNUSED)
1973 BINFO_MARKED (binfo) = 0;
1978 /* Debug info for C++ classes can get very large; try to avoid
1979 emitting it everywhere.
1981 Note that this optimization wins even when the target supports
1982 BINCL (if only slightly), and reduces the amount of work for the
1986 maybe_suppress_debug_info (tree t)
1988 /* We can't do the usual TYPE_DECL_SUPPRESS_DEBUG thing with DWARF, which
1989 does not support name references between translation units. It supports
1990 symbolic references between translation units, but only within a single
1991 executable or shared library.
1993 For DWARF 2, we handle TYPE_DECL_SUPPRESS_DEBUG by pretending
1994 that the type was never defined, so we only get the members we
1996 if (write_symbols == DWARF_DEBUG || write_symbols == NO_DEBUG)
1999 /* We might have set this earlier in cp_finish_decl. */
2000 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 0;
2002 /* If we already know how we're handling this class, handle debug info
2004 if (CLASSTYPE_INTERFACE_KNOWN (t))
2006 if (CLASSTYPE_INTERFACE_ONLY (t))
2007 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 1;
2008 /* else don't set it. */
2010 /* If the class has a vtable, write out the debug info along with
2012 else if (TYPE_CONTAINS_VPTR_P (t))
2013 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 1;
2015 /* Otherwise, just emit the debug info normally. */
2018 /* Note that we want debugging information for a base class of a class
2019 whose vtable is being emitted. Normally, this would happen because
2020 calling the constructor for a derived class implies calling the
2021 constructors for all bases, which involve initializing the
2022 appropriate vptr with the vtable for the base class; but in the
2023 presence of optimization, this initialization may be optimized
2024 away, so we tell finish_vtable_vardecl that we want the debugging
2025 information anyway. */
2028 dfs_debug_mark (tree binfo, void *data ATTRIBUTE_UNUSED)
2030 tree t = BINFO_TYPE (binfo);
2032 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
2037 /* Returns BINFO if we haven't already noted that we want debugging
2038 info for this base class. */
2041 dfs_debug_unmarkedp (tree derived, int ix, void *data ATTRIBUTE_UNUSED)
2043 tree binfo = BINFO_BASETYPE (derived, ix);
2045 return (!CLASSTYPE_DEBUG_REQUESTED (BINFO_TYPE (binfo))
2046 ? binfo : NULL_TREE);
2049 /* Write out the debugging information for TYPE, whose vtable is being
2050 emitted. Also walk through our bases and note that we want to
2051 write out information for them. This avoids the problem of not
2052 writing any debug info for intermediate basetypes whose
2053 constructors, and thus the references to their vtables, and thus
2054 the vtables themselves, were optimized away. */
2057 note_debug_info_needed (tree type)
2059 if (TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type)))
2061 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type)) = 0;
2062 rest_of_type_compilation (type, toplevel_bindings_p ());
2065 dfs_walk (TYPE_BINFO (type), dfs_debug_mark, dfs_debug_unmarkedp, 0);
2068 /* Subroutines of push_class_decls (). */
2071 setup_class_bindings (tree name, int type_binding_p)
2073 tree type_binding = NULL_TREE;
2076 /* If we've already done the lookup for this declaration, we're
2078 if (IDENTIFIER_CLASS_VALUE (name))
2081 /* First, deal with the type binding. */
2084 type_binding = lookup_member (current_class_type, name,
2085 /*protect=*/2, /*want_type=*/true);
2086 if (TREE_CODE (type_binding) == TREE_LIST
2087 && TREE_TYPE (type_binding) == error_mark_node)
2088 /* NAME is ambiguous. */
2089 push_class_level_binding (name, type_binding);
2091 pushdecl_class_level (type_binding);
2094 /* Now, do the value binding. */
2095 value_binding = lookup_member (current_class_type, name,
2096 /*protect=*/2, /*want_type=*/false);
2099 && (TREE_CODE (value_binding) == TYPE_DECL
2100 || DECL_CLASS_TEMPLATE_P (value_binding)
2101 || (TREE_CODE (value_binding) == TREE_LIST
2102 && TREE_TYPE (value_binding) == error_mark_node
2103 && (TREE_CODE (TREE_VALUE (value_binding))
2105 /* We found a type-binding, even when looking for a non-type
2106 binding. This means that we already processed this binding
2108 else if (value_binding)
2110 if (TREE_CODE (value_binding) == TREE_LIST
2111 && TREE_TYPE (value_binding) == error_mark_node)
2112 /* NAME is ambiguous. */
2113 push_class_level_binding (name, value_binding);
2116 if (BASELINK_P (value_binding))
2117 /* NAME is some overloaded functions. */
2118 value_binding = BASELINK_FUNCTIONS (value_binding);
2119 pushdecl_class_level (value_binding);
2124 /* Push class-level declarations for any names appearing in BINFO that
2128 dfs_push_type_decls (tree binfo, void *data ATTRIBUTE_UNUSED)
2133 type = BINFO_TYPE (binfo);
2134 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2135 if (DECL_NAME (fields) && TREE_CODE (fields) == TYPE_DECL
2136 && !(!same_type_p (type, current_class_type)
2137 && template_self_reference_p (type, fields)))
2138 setup_class_bindings (DECL_NAME (fields), /*type_binding_p=*/1);
2140 /* We can't just use BINFO_MARKED because envelope_add_decl uses
2141 DERIVED_FROM_P, which calls get_base_distance. */
2142 BINFO_PUSHDECLS_MARKED (binfo) = 1;
2147 /* Push class-level declarations for any names appearing in BINFO that
2148 are not TYPE_DECLS. */
2151 dfs_push_decls (tree binfo, void *data)
2153 tree type = BINFO_TYPE (binfo);
2157 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2158 if (DECL_NAME (fields)
2159 && TREE_CODE (fields) != TYPE_DECL
2160 && TREE_CODE (fields) != USING_DECL
2161 && !DECL_ARTIFICIAL (fields))
2162 setup_class_bindings (DECL_NAME (fields), /*type_binding_p=*/0);
2163 else if (TREE_CODE (fields) == FIELD_DECL
2164 && ANON_AGGR_TYPE_P (TREE_TYPE (fields)))
2165 dfs_push_decls (TYPE_BINFO (TREE_TYPE (fields)), data);
2167 method_vec = (CLASS_TYPE_P (type)
2168 ? CLASSTYPE_METHOD_VEC (type) : NULL_TREE);
2170 if (method_vec && TREE_VEC_LENGTH (method_vec) >= 3)
2175 /* Farm out constructors and destructors. */
2176 end = TREE_VEC_END (method_vec);
2178 for (methods = &TREE_VEC_ELT (method_vec, 2);
2179 methods < end && *methods;
2181 setup_class_bindings (DECL_NAME (OVL_CURRENT (*methods)),
2182 /*type_binding_p=*/0);
2185 BINFO_PUSHDECLS_MARKED (binfo) = 0;
2190 /* When entering the scope of a class, we cache all of the
2191 fields that that class provides within its inheritance
2192 lattice. Where ambiguities result, we mark them
2193 with `error_mark_node' so that if they are encountered
2194 without explicit qualification, we can emit an error
2198 push_class_decls (tree type)
2200 search_stack = push_search_level (search_stack, &search_obstack);
2202 /* Enter type declarations and mark. */
2203 dfs_walk (TYPE_BINFO (type), dfs_push_type_decls, unmarked_pushdecls_p, 0);
2205 /* Enter non-type declarations and unmark. */
2206 dfs_walk (TYPE_BINFO (type), dfs_push_decls, marked_pushdecls_p, 0);
2209 /* Here's a subroutine we need because C lacks lambdas. */
2212 dfs_unuse_fields (tree binfo, void *data ATTRIBUTE_UNUSED)
2214 tree type = TREE_TYPE (binfo);
2217 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2219 if (TREE_CODE (fields) != FIELD_DECL || DECL_ARTIFICIAL (fields))
2222 TREE_USED (fields) = 0;
2223 if (DECL_NAME (fields) == NULL_TREE
2224 && ANON_AGGR_TYPE_P (TREE_TYPE (fields)))
2225 unuse_fields (TREE_TYPE (fields));
2232 unuse_fields (tree type)
2234 dfs_walk (TYPE_BINFO (type), dfs_unuse_fields, unmarkedp, 0);
2240 /* We haven't pushed a search level when dealing with cached classes,
2241 so we'd better not try to pop it. */
2243 search_stack = pop_search_level (search_stack);
2247 print_search_statistics ()
2249 #ifdef GATHER_STATISTICS
2250 fprintf (stderr, "%d fields searched in %d[%d] calls to lookup_field[_1]\n",
2251 n_fields_searched, n_calls_lookup_field, n_calls_lookup_field_1);
2252 fprintf (stderr, "%d fnfields searched in %d calls to lookup_fnfields\n",
2253 n_outer_fields_searched, n_calls_lookup_fnfields);
2254 fprintf (stderr, "%d calls to get_base_type\n", n_calls_get_base_type);
2255 #else /* GATHER_STATISTICS */
2256 fprintf (stderr, "no search statistics\n");
2257 #endif /* GATHER_STATISTICS */
2261 init_search_processing ()
2263 gcc_obstack_init (&search_obstack);
2267 reinit_search_statistics ()
2269 #ifdef GATHER_STATISTICS
2270 n_fields_searched = 0;
2271 n_calls_lookup_field = 0, n_calls_lookup_field_1 = 0;
2272 n_calls_lookup_fnfields = 0, n_calls_lookup_fnfields_1 = 0;
2273 n_calls_get_base_type = 0;
2274 n_outer_fields_searched = 0;
2275 n_contexts_saved = 0;
2276 #endif /* GATHER_STATISTICS */
2280 add_conversions (tree binfo, void *data)
2283 tree method_vec = CLASSTYPE_METHOD_VEC (BINFO_TYPE (binfo));
2284 tree *conversions = (tree *) data;
2286 /* Some builtin types have no method vector, not even an empty one. */
2290 for (i = 2; i < TREE_VEC_LENGTH (method_vec); ++i)
2292 tree tmp = TREE_VEC_ELT (method_vec, i);
2295 if (!tmp || ! DECL_CONV_FN_P (OVL_CURRENT (tmp)))
2298 name = DECL_NAME (OVL_CURRENT (tmp));
2300 /* Make sure we don't already have this conversion. */
2301 if (! IDENTIFIER_MARKED (name))
2303 *conversions = tree_cons (binfo, tmp, *conversions);
2304 IDENTIFIER_MARKED (name) = 1;
2310 /* Return a TREE_LIST containing all the non-hidden user-defined
2311 conversion functions for TYPE (and its base-classes). The
2312 TREE_VALUE of each node is a FUNCTION_DECL or an OVERLOAD
2313 containing the conversion functions. The TREE_PURPOSE is the BINFO
2314 from which the conversion functions in this node were selected. */
2317 lookup_conversions (tree type)
2320 tree conversions = NULL_TREE;
2322 complete_type (type);
2323 bfs_walk (TYPE_BINFO (type), add_conversions, 0, &conversions);
2325 for (t = conversions; t; t = TREE_CHAIN (t))
2326 IDENTIFIER_MARKED (DECL_NAME (OVL_CURRENT (TREE_VALUE (t)))) = 0;
2337 /* Check whether the empty class indicated by EMPTY_BINFO is also present
2338 at offset 0 in COMPARE_TYPE, and set found_overlap if so. */
2341 dfs_check_overlap (tree empty_binfo, void *data)
2343 struct overlap_info *oi = (struct overlap_info *) data;
2345 for (binfo = TYPE_BINFO (oi->compare_type);
2347 binfo = BINFO_BASETYPE (binfo, 0))
2349 if (BINFO_TYPE (binfo) == BINFO_TYPE (empty_binfo))
2351 oi->found_overlap = 1;
2354 else if (BINFO_BASETYPES (binfo) == NULL_TREE)
2361 /* Trivial function to stop base traversal when we find something. */
2364 dfs_no_overlap_yet (tree derived, int ix, void *data)
2366 tree binfo = BINFO_BASETYPE (derived, ix);
2367 struct overlap_info *oi = (struct overlap_info *) data;
2369 return !oi->found_overlap ? binfo : NULL_TREE;
2372 /* Returns nonzero if EMPTY_TYPE or any of its bases can also be found at
2373 offset 0 in NEXT_TYPE. Used in laying out empty base class subobjects. */
2376 types_overlap_p (tree empty_type, tree next_type)
2378 struct overlap_info oi;
2380 if (! IS_AGGR_TYPE (next_type))
2382 oi.compare_type = next_type;
2383 oi.found_overlap = 0;
2384 dfs_walk (TYPE_BINFO (empty_type), dfs_check_overlap,
2385 dfs_no_overlap_yet, &oi);
2386 return oi.found_overlap;
2389 /* Given a vtable VAR, determine which of the inherited classes the vtable
2390 inherits (in a loose sense) functions from.
2392 FIXME: This does not work with the new ABI. */
2395 binfo_for_vtable (tree var)
2397 tree main_binfo = TYPE_BINFO (DECL_CONTEXT (var));
2398 tree binfos = TYPE_BINFO_BASETYPES (BINFO_TYPE (main_binfo));
2399 int n_baseclasses = CLASSTYPE_N_BASECLASSES (BINFO_TYPE (main_binfo));
2402 for (i = 0; i < n_baseclasses; i++)
2404 tree base_binfo = TREE_VEC_ELT (binfos, i);
2405 if (base_binfo != NULL_TREE && BINFO_VTABLE (base_binfo) == var)
2409 /* If no secondary base classes matched, return the primary base, if
2411 if (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (main_binfo)))
2412 return get_primary_binfo (main_binfo);
2417 /* Returns the binfo of the first direct or indirect virtual base derived
2418 from BINFO, or NULL if binfo is not via virtual. */
2421 binfo_from_vbase (tree binfo)
2423 for (; binfo; binfo = BINFO_INHERITANCE_CHAIN (binfo))
2425 if (TREE_VIA_VIRTUAL (binfo))
2431 /* Returns the binfo of the first direct or indirect virtual base derived
2432 from BINFO up to the TREE_TYPE, LIMIT, or NULL if binfo is not
2436 binfo_via_virtual (tree binfo, tree limit)
2438 for (; binfo && (!limit || !same_type_p (BINFO_TYPE (binfo), limit));
2439 binfo = BINFO_INHERITANCE_CHAIN (binfo))
2441 if (TREE_VIA_VIRTUAL (binfo))
2447 /* BINFO is a base binfo in the complete type BINFO_TYPE (HERE).
2448 Find the equivalent binfo within whatever graph HERE is located.
2449 This is the inverse of original_binfo. */
2452 copied_binfo (tree binfo, tree here)
2454 tree result = NULL_TREE;
2456 if (TREE_VIA_VIRTUAL (binfo))
2460 for (t = here; BINFO_INHERITANCE_CHAIN (t);
2461 t = BINFO_INHERITANCE_CHAIN (t))
2464 result = purpose_member (BINFO_TYPE (binfo),
2465 CLASSTYPE_VBASECLASSES (BINFO_TYPE (t)));
2466 result = TREE_VALUE (result);
2468 else if (BINFO_INHERITANCE_CHAIN (binfo))
2473 base_binfos = copied_binfo (BINFO_INHERITANCE_CHAIN (binfo), here);
2474 base_binfos = BINFO_BASETYPES (base_binfos);
2475 n = TREE_VEC_LENGTH (base_binfos);
2476 for (ix = 0; ix != n; ix++)
2478 tree base = TREE_VEC_ELT (base_binfos, ix);
2480 if (BINFO_TYPE (base) == BINFO_TYPE (binfo))
2489 my_friendly_assert (BINFO_TYPE (here) == BINFO_TYPE (binfo), 20030202);
2493 my_friendly_assert (result, 20030202);
2497 /* BINFO is some base binfo of HERE, within some other
2498 hierarchy. Return the equivalent binfo, but in the hierarchy
2499 dominated by HERE. This is the inverse of copied_binfo. If BINFO
2500 is not a base binfo of HERE, returns NULL_TREE. */
2503 original_binfo (tree binfo, tree here)
2507 if (BINFO_TYPE (binfo) == BINFO_TYPE (here))
2509 else if (TREE_VIA_VIRTUAL (binfo))
2511 result = purpose_member (BINFO_TYPE (binfo),
2512 CLASSTYPE_VBASECLASSES (BINFO_TYPE (here)));
2514 result = TREE_VALUE (result);
2516 else if (BINFO_INHERITANCE_CHAIN (binfo))
2520 base_binfos = original_binfo (BINFO_INHERITANCE_CHAIN (binfo), here);
2525 base_binfos = BINFO_BASETYPES (base_binfos);
2526 n = TREE_VEC_LENGTH (base_binfos);
2527 for (ix = 0; ix != n; ix++)
2529 tree base = TREE_VEC_ELT (base_binfos, ix);
2531 if (BINFO_TYPE (base) == BINFO_TYPE (binfo))