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, 2004, 2005, 2007, 2008, 2009, 2010, 2011
5 Free Software Foundation, Inc.
6 Contributed by Michael Tiemann (tiemann@cygnus.com)
8 This file is part of GCC.
10 GCC is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3, or (at your option)
15 GCC is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with GCC; see the file COPYING3. If not see
22 <http://www.gnu.org/licenses/>. */
24 /* High-level class interface. */
28 #include "coretypes.h"
38 static int is_subobject_of_p (tree, tree);
39 static tree dfs_lookup_base (tree, void *);
40 static tree dfs_dcast_hint_pre (tree, void *);
41 static tree dfs_dcast_hint_post (tree, void *);
42 static tree dfs_debug_mark (tree, void *);
43 static tree dfs_walk_once_r (tree, tree (*pre_fn) (tree, void *),
44 tree (*post_fn) (tree, void *), void *data);
45 static void dfs_unmark_r (tree);
46 static int check_hidden_convs (tree, int, int, tree, tree, tree);
47 static tree split_conversions (tree, tree, tree, tree);
48 static int lookup_conversions_r (tree, int, int,
49 tree, tree, tree, tree, tree *, tree *);
50 static int look_for_overrides_r (tree, tree);
51 static tree lookup_field_r (tree, void *);
52 static tree dfs_accessible_post (tree, void *);
53 static tree dfs_walk_once_accessible_r (tree, bool, bool,
54 tree (*pre_fn) (tree, void *),
55 tree (*post_fn) (tree, void *),
57 static tree dfs_walk_once_accessible (tree, bool,
58 tree (*pre_fn) (tree, void *),
59 tree (*post_fn) (tree, void *),
61 static tree dfs_access_in_type (tree, void *);
62 static access_kind access_in_type (tree, tree);
63 static int protected_accessible_p (tree, tree, tree);
64 static int friend_accessible_p (tree, tree, tree);
65 static tree dfs_get_pure_virtuals (tree, void *);
68 /* Variables for gathering statistics. */
69 #ifdef GATHER_STATISTICS
70 static int n_fields_searched;
71 static int n_calls_lookup_field, n_calls_lookup_field_1;
72 static int n_calls_lookup_fnfields, n_calls_lookup_fnfields_1;
73 static int n_calls_get_base_type;
74 static int n_outer_fields_searched;
75 static int n_contexts_saved;
76 #endif /* GATHER_STATISTICS */
79 /* Data for lookup_base and its workers. */
81 struct lookup_base_data_s
83 tree t; /* type being searched. */
84 tree base; /* The base type we're looking for. */
85 tree binfo; /* Found binfo. */
86 bool via_virtual; /* Found via a virtual path. */
87 bool ambiguous; /* Found multiply ambiguous */
88 bool repeated_base; /* Whether there are repeated bases in the
90 bool want_any; /* Whether we want any matching binfo. */
93 /* Worker function for lookup_base. See if we've found the desired
94 base and update DATA_ (a pointer to LOOKUP_BASE_DATA_S). */
97 dfs_lookup_base (tree binfo, void *data_)
99 struct lookup_base_data_s *data = (struct lookup_base_data_s *) data_;
101 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->base))
107 = binfo_via_virtual (data->binfo, data->t) != NULL_TREE;
109 if (!data->repeated_base)
110 /* If there are no repeated bases, we can stop now. */
113 if (data->want_any && !data->via_virtual)
114 /* If this is a non-virtual base, then we can't do
118 return dfs_skip_bases;
122 gcc_assert (binfo != data->binfo);
124 /* We've found more than one matching binfo. */
127 /* This is immediately ambiguous. */
128 data->binfo = NULL_TREE;
129 data->ambiguous = true;
130 return error_mark_node;
133 /* Prefer one via a non-virtual path. */
134 if (!binfo_via_virtual (binfo, data->t))
137 data->via_virtual = false;
141 /* There must be repeated bases, otherwise we'd have stopped
142 on the first base we found. */
143 return dfs_skip_bases;
150 /* Returns true if type BASE is accessible in T. (BASE is known to be
151 a (possibly non-proper) base class of T.) If CONSIDER_LOCAL_P is
152 true, consider any special access of the current scope, or access
153 bestowed by friendship. */
156 accessible_base_p (tree t, tree base, bool consider_local_p)
160 /* [class.access.base]
162 A base class is said to be accessible if an invented public
163 member of the base class is accessible.
165 If BASE is a non-proper base, this condition is trivially
167 if (same_type_p (t, base))
169 /* Rather than inventing a public member, we use the implicit
170 public typedef created in the scope of every class. */
171 decl = TYPE_FIELDS (base);
172 while (!DECL_SELF_REFERENCE_P (decl))
173 decl = DECL_CHAIN (decl);
174 while (ANON_AGGR_TYPE_P (t))
175 t = TYPE_CONTEXT (t);
176 return accessible_p (t, decl, consider_local_p);
179 /* Lookup BASE in the hierarchy dominated by T. Do access checking as
180 ACCESS specifies. Return the binfo we discover. If KIND_PTR is
181 non-NULL, fill with information about what kind of base we
184 If the base is inaccessible, or ambiguous, and the ba_quiet bit is
185 not set in ACCESS, then an error is issued and error_mark_node is
186 returned. If the ba_quiet bit is set, then no error is issued and
187 NULL_TREE is returned. */
190 lookup_base (tree t, tree base, base_access access, base_kind *kind_ptr)
196 if (t == error_mark_node || base == error_mark_node)
199 *kind_ptr = bk_not_base;
200 return error_mark_node;
202 gcc_assert (TYPE_P (base));
211 t = complete_type (TYPE_MAIN_VARIANT (t));
212 t_binfo = TYPE_BINFO (t);
215 base = TYPE_MAIN_VARIANT (base);
217 /* If BASE is incomplete, it can't be a base of T--and instantiating it
218 might cause an error. */
219 if (t_binfo && CLASS_TYPE_P (base) && COMPLETE_OR_OPEN_TYPE_P (base))
221 struct lookup_base_data_s data;
225 data.binfo = NULL_TREE;
226 data.ambiguous = data.via_virtual = false;
227 data.repeated_base = CLASSTYPE_REPEATED_BASE_P (t);
228 data.want_any = access == ba_any;
230 dfs_walk_once (t_binfo, dfs_lookup_base, NULL, &data);
234 bk = data.ambiguous ? bk_ambig : bk_not_base;
235 else if (binfo == t_binfo)
237 else if (data.via_virtual)
248 /* Check that the base is unambiguous and accessible. */
249 if (access != ba_any)
256 if (!(access & ba_quiet))
258 error ("%qT is an ambiguous base of %qT", base, t);
259 binfo = error_mark_node;
264 if ((access & ba_check_bit)
265 /* If BASE is incomplete, then BASE and TYPE are probably
266 the same, in which case BASE is accessible. If they
267 are not the same, then TYPE is invalid. In that case,
268 there's no need to issue another error here, and
269 there's no implicit typedef to use in the code that
270 follows, so we skip the check. */
271 && COMPLETE_TYPE_P (base)
272 && !accessible_base_p (t, base, !(access & ba_ignore_scope)))
274 if (!(access & ba_quiet))
276 error ("%qT is an inaccessible base of %qT", base, t);
277 binfo = error_mark_node;
281 bk = bk_inaccessible;
292 /* Data for dcast_base_hint walker. */
296 tree subtype; /* The base type we're looking for. */
297 int virt_depth; /* Number of virtual bases encountered from most
299 tree offset; /* Best hint offset discovered so far. */
300 bool repeated_base; /* Whether there are repeated bases in the
304 /* Worker for dcast_base_hint. Search for the base type being cast
308 dfs_dcast_hint_pre (tree binfo, void *data_)
310 struct dcast_data_s *data = (struct dcast_data_s *) data_;
312 if (BINFO_VIRTUAL_P (binfo))
315 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->subtype))
317 if (data->virt_depth)
319 data->offset = ssize_int (-1);
323 data->offset = ssize_int (-3);
325 data->offset = BINFO_OFFSET (binfo);
327 return data->repeated_base ? dfs_skip_bases : data->offset;
333 /* Worker for dcast_base_hint. Track the virtual depth. */
336 dfs_dcast_hint_post (tree binfo, void *data_)
338 struct dcast_data_s *data = (struct dcast_data_s *) data_;
340 if (BINFO_VIRTUAL_P (binfo))
346 /* The dynamic cast runtime needs a hint about how the static SUBTYPE type
347 started from is related to the required TARGET type, in order to optimize
348 the inheritance graph search. This information is independent of the
349 current context, and ignores private paths, hence get_base_distance is
350 inappropriate. Return a TREE specifying the base offset, BOFF.
351 BOFF >= 0, there is only one public non-virtual SUBTYPE base at offset BOFF,
352 and there are no public virtual SUBTYPE bases.
353 BOFF == -1, SUBTYPE occurs as multiple public virtual or non-virtual bases.
354 BOFF == -2, SUBTYPE is not a public base.
355 BOFF == -3, SUBTYPE occurs as multiple public non-virtual bases. */
358 dcast_base_hint (tree subtype, tree target)
360 struct dcast_data_s data;
362 data.subtype = subtype;
364 data.offset = NULL_TREE;
365 data.repeated_base = CLASSTYPE_REPEATED_BASE_P (target);
367 dfs_walk_once_accessible (TYPE_BINFO (target), /*friends=*/false,
368 dfs_dcast_hint_pre, dfs_dcast_hint_post, &data);
369 return data.offset ? data.offset : ssize_int (-2);
372 /* Search for a member with name NAME in a multiple inheritance
373 lattice specified by TYPE. If it does not exist, return NULL_TREE.
374 If the member is ambiguously referenced, return `error_mark_node'.
375 Otherwise, return a DECL with the indicated name. If WANT_TYPE is
376 true, type declarations are preferred. */
378 /* Do a 1-level search for NAME as a member of TYPE. The caller must
379 figure out whether it can access this field. (Since it is only one
380 level, this is reasonable.) */
383 lookup_field_1 (tree type, tree name, bool want_type)
387 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
388 || TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM
389 || TREE_CODE (type) == TYPENAME_TYPE)
390 /* The TYPE_FIELDS of a TEMPLATE_TYPE_PARM and
391 BOUND_TEMPLATE_TEMPLATE_PARM are not fields at all;
392 instead TYPE_FIELDS is the TEMPLATE_PARM_INDEX. (Miraculously,
393 the code often worked even when we treated the index as a list
395 The TYPE_FIELDS of TYPENAME_TYPE is its TYPENAME_TYPE_FULLNAME. */
398 if (CLASSTYPE_SORTED_FIELDS (type))
400 tree *fields = &CLASSTYPE_SORTED_FIELDS (type)->elts[0];
401 int lo = 0, hi = CLASSTYPE_SORTED_FIELDS (type)->len;
408 #ifdef GATHER_STATISTICS
410 #endif /* GATHER_STATISTICS */
412 if (DECL_NAME (fields[i]) > name)
414 else if (DECL_NAME (fields[i]) < name)
420 /* We might have a nested class and a field with the
421 same name; we sorted them appropriately via
422 field_decl_cmp, so just look for the first or last
423 field with this name. */
428 while (i >= lo && DECL_NAME (fields[i]) == name);
429 if (TREE_CODE (field) != TYPE_DECL
430 && !DECL_TYPE_TEMPLATE_P (field))
437 while (i < hi && DECL_NAME (fields[i]) == name);
442 field = strip_using_decl (field);
443 if (is_overloaded_fn (field))
453 field = TYPE_FIELDS (type);
455 #ifdef GATHER_STATISTICS
456 n_calls_lookup_field_1++;
457 #endif /* GATHER_STATISTICS */
458 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
462 #ifdef GATHER_STATISTICS
464 #endif /* GATHER_STATISTICS */
465 gcc_assert (DECL_P (field));
466 if (DECL_NAME (field) == NULL_TREE
467 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
469 tree temp = lookup_field_1 (TREE_TYPE (field), name, want_type);
474 if (TREE_CODE (decl) == USING_DECL
475 && DECL_NAME (decl) == name)
477 decl = strip_using_decl (decl);
478 if (is_overloaded_fn (decl))
482 if (DECL_NAME (decl) == name
484 || TREE_CODE (decl) == TYPE_DECL
485 || DECL_TYPE_TEMPLATE_P (decl)))
489 if (name == vptr_identifier)
491 /* Give the user what s/he thinks s/he wants. */
492 if (TYPE_POLYMORPHIC_P (type))
493 return TYPE_VFIELD (type);
498 /* Return the FUNCTION_DECL, RECORD_TYPE, UNION_TYPE, or
499 NAMESPACE_DECL corresponding to the innermost non-block scope. */
504 /* There are a number of cases we need to be aware of here:
505 current_class_type current_function_decl
512 Those last two make life interesting. If we're in a function which is
513 itself inside a class, we need decls to go into the fn's decls (our
514 second case below). But if we're in a class and the class itself is
515 inside a function, we need decls to go into the decls for the class. To
516 achieve this last goal, we must see if, when both current_class_ptr and
517 current_function_decl are set, the class was declared inside that
518 function. If so, we know to put the decls into the class's scope. */
519 if (current_function_decl && current_class_type
520 && ((DECL_FUNCTION_MEMBER_P (current_function_decl)
521 && same_type_p (DECL_CONTEXT (current_function_decl),
523 || (DECL_FRIEND_CONTEXT (current_function_decl)
524 && same_type_p (DECL_FRIEND_CONTEXT (current_function_decl),
525 current_class_type))))
526 return current_function_decl;
527 if (current_class_type)
528 return current_class_type;
529 if (current_function_decl)
530 return current_function_decl;
531 return current_namespace;
534 /* Returns nonzero if we are currently in a function scope. Note
535 that this function returns zero if we are within a local class, but
536 not within a member function body of the local class. */
539 at_function_scope_p (void)
541 tree cs = current_scope ();
542 return cs && TREE_CODE (cs) == FUNCTION_DECL;
545 /* Returns true if the innermost active scope is a class scope. */
548 at_class_scope_p (void)
550 tree cs = current_scope ();
551 return cs && TYPE_P (cs);
554 /* Returns true if the innermost active scope is a namespace scope. */
557 at_namespace_scope_p (void)
559 tree cs = current_scope ();
560 return cs && TREE_CODE (cs) == NAMESPACE_DECL;
563 /* Return the scope of DECL, as appropriate when doing name-lookup. */
566 context_for_name_lookup (tree decl)
570 For the purposes of name lookup, after the anonymous union
571 definition, the members of the anonymous union are considered to
572 have been defined in the scope in which the anonymous union is
574 tree context = DECL_CONTEXT (decl);
576 while (context && TYPE_P (context) && ANON_AGGR_TYPE_P (context))
577 context = TYPE_CONTEXT (context);
579 context = global_namespace;
584 /* The accessibility routines use BINFO_ACCESS for scratch space
585 during the computation of the accessibility of some declaration. */
587 #define BINFO_ACCESS(NODE) \
588 ((access_kind) ((TREE_PUBLIC (NODE) << 1) | TREE_PRIVATE (NODE)))
590 /* Set the access associated with NODE to ACCESS. */
592 #define SET_BINFO_ACCESS(NODE, ACCESS) \
593 ((TREE_PUBLIC (NODE) = ((ACCESS) & 2) != 0), \
594 (TREE_PRIVATE (NODE) = ((ACCESS) & 1) != 0))
596 /* Called from access_in_type via dfs_walk. Calculate the access to
597 DATA (which is really a DECL) in BINFO. */
600 dfs_access_in_type (tree binfo, void *data)
602 tree decl = (tree) data;
603 tree type = BINFO_TYPE (binfo);
604 access_kind access = ak_none;
606 if (context_for_name_lookup (decl) == type)
608 /* If we have descended to the scope of DECL, just note the
609 appropriate access. */
610 if (TREE_PRIVATE (decl))
612 else if (TREE_PROTECTED (decl))
613 access = ak_protected;
619 /* First, check for an access-declaration that gives us more
620 access to the DECL. The CONST_DECL for an enumeration
621 constant will not have DECL_LANG_SPECIFIC, and thus no
623 if (DECL_LANG_SPECIFIC (decl) && !DECL_DISCRIMINATOR_P (decl))
625 tree decl_access = purpose_member (type, DECL_ACCESS (decl));
629 decl_access = TREE_VALUE (decl_access);
631 if (decl_access == access_public_node)
633 else if (decl_access == access_protected_node)
634 access = ak_protected;
635 else if (decl_access == access_private_node)
646 VEC(tree,gc) *accesses;
648 /* Otherwise, scan our baseclasses, and pick the most favorable
650 accesses = BINFO_BASE_ACCESSES (binfo);
651 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
653 tree base_access = VEC_index (tree, accesses, i);
654 access_kind base_access_now = BINFO_ACCESS (base_binfo);
656 if (base_access_now == ak_none || base_access_now == ak_private)
657 /* If it was not accessible in the base, or only
658 accessible as a private member, we can't access it
660 base_access_now = ak_none;
661 else if (base_access == access_protected_node)
662 /* Public and protected members in the base become
664 base_access_now = ak_protected;
665 else if (base_access == access_private_node)
666 /* Public and protected members in the base become
668 base_access_now = ak_private;
670 /* See if the new access, via this base, gives more
671 access than our previous best access. */
672 if (base_access_now != ak_none
673 && (access == ak_none || base_access_now < access))
675 access = base_access_now;
677 /* If the new access is public, we can't do better. */
678 if (access == ak_public)
685 /* Note the access to DECL in TYPE. */
686 SET_BINFO_ACCESS (binfo, access);
691 /* Return the access to DECL in TYPE. */
694 access_in_type (tree type, tree decl)
696 tree binfo = TYPE_BINFO (type);
698 /* We must take into account
702 If a name can be reached by several paths through a multiple
703 inheritance graph, the access is that of the path that gives
706 The algorithm we use is to make a post-order depth-first traversal
707 of the base-class hierarchy. As we come up the tree, we annotate
708 each node with the most lenient access. */
709 dfs_walk_once (binfo, NULL, dfs_access_in_type, decl);
711 return BINFO_ACCESS (binfo);
714 /* Returns nonzero if it is OK to access DECL through an object
715 indicated by BINFO in the context of DERIVED. */
718 protected_accessible_p (tree decl, tree derived, tree binfo)
722 /* We're checking this clause from [class.access.base]
724 m as a member of N is protected, and the reference occurs in a
725 member or friend of class N, or in a member or friend of a
726 class P derived from N, where m as a member of P is public, private
729 Here DERIVED is a possible P, DECL is m and BINFO_TYPE (binfo) is N. */
731 /* If DERIVED isn't derived from N, then it can't be a P. */
732 if (!DERIVED_FROM_P (BINFO_TYPE (binfo), derived))
735 access = access_in_type (derived, decl);
737 /* If m is inaccessible in DERIVED, then it's not a P. */
738 if (access == ak_none)
743 When a friend or a member function of a derived class references
744 a protected nonstatic member of a base class, an access check
745 applies in addition to those described earlier in clause
746 _class.access_) Except when forming a pointer to member
747 (_expr.unary.op_), the access must be through a pointer to,
748 reference to, or object of the derived class itself (or any class
749 derived from that class) (_expr.ref_). If the access is to form
750 a pointer to member, the nested-name-specifier shall name the
751 derived class (or any class derived from that class). */
752 if (DECL_NONSTATIC_MEMBER_P (decl))
754 /* We can tell through what the reference is occurring by
755 chasing BINFO up to the root. */
757 while (BINFO_INHERITANCE_CHAIN (t))
758 t = BINFO_INHERITANCE_CHAIN (t);
760 if (!DERIVED_FROM_P (derived, BINFO_TYPE (t)))
767 /* Returns nonzero if SCOPE is a friend of a type which would be able
768 to access DECL through the object indicated by BINFO. */
771 friend_accessible_p (tree scope, tree decl, tree binfo)
773 tree befriending_classes;
779 if (TREE_CODE (scope) == FUNCTION_DECL
780 || DECL_FUNCTION_TEMPLATE_P (scope))
781 befriending_classes = DECL_BEFRIENDING_CLASSES (scope);
782 else if (TYPE_P (scope))
783 befriending_classes = CLASSTYPE_BEFRIENDING_CLASSES (scope);
787 for (t = befriending_classes; t; t = TREE_CHAIN (t))
788 if (protected_accessible_p (decl, TREE_VALUE (t), binfo))
791 /* Nested classes have the same access as their enclosing types, as
792 per DR 45 (this is a change from the standard). */
794 for (t = TYPE_CONTEXT (scope); t && TYPE_P (t); t = TYPE_CONTEXT (t))
795 if (protected_accessible_p (decl, t, binfo))
798 if (TREE_CODE (scope) == FUNCTION_DECL
799 || DECL_FUNCTION_TEMPLATE_P (scope))
801 /* Perhaps this SCOPE is a member of a class which is a
803 if (DECL_CLASS_SCOPE_P (scope)
804 && friend_accessible_p (DECL_CONTEXT (scope), decl, binfo))
807 /* Or an instantiation of something which is a friend. */
808 if (DECL_TEMPLATE_INFO (scope))
811 /* Increment processing_template_decl to make sure that
812 dependent_type_p works correctly. */
813 ++processing_template_decl;
814 ret = friend_accessible_p (DECL_TI_TEMPLATE (scope), decl, binfo);
815 --processing_template_decl;
823 /* Called via dfs_walk_once_accessible from accessible_p */
826 dfs_accessible_post (tree binfo, void *data ATTRIBUTE_UNUSED)
828 if (BINFO_ACCESS (binfo) != ak_none)
830 tree scope = current_scope ();
831 if (scope && TREE_CODE (scope) != NAMESPACE_DECL
832 && is_friend (BINFO_TYPE (binfo), scope))
839 /* DECL is a declaration from a base class of TYPE, which was the
840 class used to name DECL. Return nonzero if, in the current
841 context, DECL is accessible. If TYPE is actually a BINFO node,
842 then we can tell in what context the access is occurring by looking
843 at the most derived class along the path indicated by BINFO. If
844 CONSIDER_LOCAL is true, do consider special access the current
845 scope or friendship thereof we might have. */
848 accessible_p (tree type, tree decl, bool consider_local_p)
854 /* Nonzero if it's OK to access DECL if it has protected
855 accessibility in TYPE. */
856 int protected_ok = 0;
858 /* If this declaration is in a block or namespace scope, there's no
860 if (!TYPE_P (context_for_name_lookup (decl)))
863 /* There is no need to perform access checks inside a thunk. */
864 scope = current_scope ();
865 if (scope && DECL_THUNK_P (scope))
868 /* In a template declaration, we cannot be sure whether the
869 particular specialization that is instantiated will be a friend
870 or not. Therefore, all access checks are deferred until
871 instantiation. However, PROCESSING_TEMPLATE_DECL is set in the
872 parameter list for a template (because we may see dependent types
873 in default arguments for template parameters), and access
874 checking should be performed in the outermost parameter list. */
875 if (processing_template_decl
876 && (!processing_template_parmlist || processing_template_decl > 1))
882 type = BINFO_TYPE (type);
885 binfo = TYPE_BINFO (type);
887 /* [class.access.base]
889 A member m is accessible when named in class N if
891 --m as a member of N is public, or
893 --m as a member of N is private, and the reference occurs in a
894 member or friend of class N, or
896 --m as a member of N is protected, and the reference occurs in a
897 member or friend of class N, or in a member or friend of a
898 class P derived from N, where m as a member of P is private or
901 --there exists a base class B of N that is accessible at the point
902 of reference, and m is accessible when named in class B.
904 We walk the base class hierarchy, checking these conditions. */
906 if (consider_local_p)
908 /* Figure out where the reference is occurring. Check to see if
909 DECL is private or protected in this scope, since that will
910 determine whether protected access is allowed. */
911 if (current_class_type)
912 protected_ok = protected_accessible_p (decl,
913 current_class_type, binfo);
915 /* Now, loop through the classes of which we are a friend. */
917 protected_ok = friend_accessible_p (scope, decl, binfo);
920 /* Standardize the binfo that access_in_type will use. We don't
921 need to know what path was chosen from this point onwards. */
922 binfo = TYPE_BINFO (type);
924 /* Compute the accessibility of DECL in the class hierarchy
925 dominated by type. */
926 access = access_in_type (type, decl);
927 if (access == ak_public
928 || (access == ak_protected && protected_ok))
931 if (!consider_local_p)
934 /* Walk the hierarchy again, looking for a base class that allows
936 return dfs_walk_once_accessible (binfo, /*friends=*/true,
937 NULL, dfs_accessible_post, NULL)
941 struct lookup_field_info {
942 /* The type in which we're looking. */
944 /* The name of the field for which we're looking. */
946 /* If non-NULL, the current result of the lookup. */
948 /* The path to RVAL. */
950 /* If non-NULL, the lookup was ambiguous, and this is a list of the
953 /* If nonzero, we are looking for types, not data members. */
955 /* If something went wrong, a message indicating what. */
959 /* Nonzero for a class member means that it is shared between all objects
962 [class.member.lookup]:If the resulting set of declarations are not all
963 from sub-objects of the same type, or the set has a nonstatic member
964 and includes members from distinct sub-objects, there is an ambiguity
965 and the program is ill-formed.
967 This function checks that T contains no nonstatic members. */
970 shared_member_p (tree t)
972 if (TREE_CODE (t) == VAR_DECL || TREE_CODE (t) == TYPE_DECL \
973 || TREE_CODE (t) == CONST_DECL)
975 if (is_overloaded_fn (t))
978 for (; t; t = OVL_NEXT (t))
980 tree fn = OVL_CURRENT (t);
981 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
989 /* Routine to see if the sub-object denoted by the binfo PARENT can be
990 found as a base class and sub-object of the object denoted by
994 is_subobject_of_p (tree parent, tree binfo)
998 for (probe = parent; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1002 if (BINFO_VIRTUAL_P (probe))
1003 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (binfo))
1009 /* DATA is really a struct lookup_field_info. Look for a field with
1010 the name indicated there in BINFO. If this function returns a
1011 non-NULL value it is the result of the lookup. Called from
1012 lookup_field via breadth_first_search. */
1015 lookup_field_r (tree binfo, void *data)
1017 struct lookup_field_info *lfi = (struct lookup_field_info *) data;
1018 tree type = BINFO_TYPE (binfo);
1019 tree nval = NULL_TREE;
1021 /* If this is a dependent base, don't look in it. */
1022 if (BINFO_DEPENDENT_BASE_P (binfo))
1025 /* If this base class is hidden by the best-known value so far, we
1026 don't need to look. */
1027 if (lfi->rval_binfo && BINFO_INHERITANCE_CHAIN (binfo) == lfi->rval_binfo
1028 && !BINFO_VIRTUAL_P (binfo))
1029 return dfs_skip_bases;
1031 /* First, look for a function. There can't be a function and a data
1032 member with the same name, and if there's a function and a type
1033 with the same name, the type is hidden by the function. */
1034 if (!lfi->want_type)
1035 nval = lookup_fnfields_slot (type, lfi->name);
1038 /* Look for a data member or type. */
1039 nval = lookup_field_1 (type, lfi->name, lfi->want_type);
1041 /* If there is no declaration with the indicated name in this type,
1042 then there's nothing to do. */
1046 /* If we're looking up a type (as with an elaborated type specifier)
1047 we ignore all non-types we find. */
1048 if (lfi->want_type && TREE_CODE (nval) != TYPE_DECL
1049 && !DECL_TYPE_TEMPLATE_P (nval))
1051 if (lfi->name == TYPE_IDENTIFIER (type))
1053 /* If the aggregate has no user defined constructors, we allow
1054 it to have fields with the same name as the enclosing type.
1055 If we are looking for that name, find the corresponding
1057 for (nval = TREE_CHAIN (nval); nval; nval = TREE_CHAIN (nval))
1058 if (DECL_NAME (nval) == lfi->name
1059 && TREE_CODE (nval) == TYPE_DECL)
1064 if (!nval && CLASSTYPE_NESTED_UTDS (type) != NULL)
1066 binding_entry e = binding_table_find (CLASSTYPE_NESTED_UTDS (type),
1069 nval = TYPE_MAIN_DECL (e->type);
1075 /* If the lookup already found a match, and the new value doesn't
1076 hide the old one, we might have an ambiguity. */
1078 && !is_subobject_of_p (lfi->rval_binfo, binfo))
1081 if (nval == lfi->rval && shared_member_p (nval))
1082 /* The two things are really the same. */
1084 else if (is_subobject_of_p (binfo, lfi->rval_binfo))
1085 /* The previous value hides the new one. */
1089 /* We have a real ambiguity. We keep a chain of all the
1091 if (!lfi->ambiguous && lfi->rval)
1093 /* This is the first time we noticed an ambiguity. Add
1094 what we previously thought was a reasonable candidate
1096 lfi->ambiguous = tree_cons (NULL_TREE, lfi->rval, NULL_TREE);
1097 TREE_TYPE (lfi->ambiguous) = error_mark_node;
1100 /* Add the new value. */
1101 lfi->ambiguous = tree_cons (NULL_TREE, nval, lfi->ambiguous);
1102 TREE_TYPE (lfi->ambiguous) = error_mark_node;
1103 lfi->errstr = G_("request for member %qD is ambiguous");
1109 lfi->rval_binfo = binfo;
1113 /* Don't look for constructors or destructors in base classes. */
1114 if (IDENTIFIER_CTOR_OR_DTOR_P (lfi->name))
1115 return dfs_skip_bases;
1119 /* Return a "baselink" with BASELINK_BINFO, BASELINK_ACCESS_BINFO,
1120 BASELINK_FUNCTIONS, and BASELINK_OPTYPE set to BINFO, ACCESS_BINFO,
1121 FUNCTIONS, and OPTYPE respectively. */
1124 build_baselink (tree binfo, tree access_binfo, tree functions, tree optype)
1128 gcc_assert (TREE_CODE (functions) == FUNCTION_DECL
1129 || TREE_CODE (functions) == TEMPLATE_DECL
1130 || TREE_CODE (functions) == TEMPLATE_ID_EXPR
1131 || TREE_CODE (functions) == OVERLOAD);
1132 gcc_assert (!optype || TYPE_P (optype));
1133 gcc_assert (TREE_TYPE (functions));
1135 baselink = make_node (BASELINK);
1136 TREE_TYPE (baselink) = TREE_TYPE (functions);
1137 BASELINK_BINFO (baselink) = binfo;
1138 BASELINK_ACCESS_BINFO (baselink) = access_binfo;
1139 BASELINK_FUNCTIONS (baselink) = functions;
1140 BASELINK_OPTYPE (baselink) = optype;
1145 /* Look for a member named NAME in an inheritance lattice dominated by
1146 XBASETYPE. If PROTECT is 0 or two, we do not check access. If it
1147 is 1, we enforce accessibility. If PROTECT is zero, then, for an
1148 ambiguous lookup, we return NULL. If PROTECT is 1, we issue error
1149 messages about inaccessible or ambiguous lookup. If PROTECT is 2,
1150 we return a TREE_LIST whose TREE_TYPE is error_mark_node and whose
1151 TREE_VALUEs are the list of ambiguous candidates.
1153 WANT_TYPE is 1 when we should only return TYPE_DECLs.
1155 If nothing can be found return NULL_TREE and do not issue an error. */
1158 lookup_member (tree xbasetype, tree name, int protect, bool want_type,
1159 tsubst_flags_t complain)
1161 tree rval, rval_binfo = NULL_TREE;
1162 tree type = NULL_TREE, basetype_path = NULL_TREE;
1163 struct lookup_field_info lfi;
1165 /* rval_binfo is the binfo associated with the found member, note,
1166 this can be set with useful information, even when rval is not
1167 set, because it must deal with ALL members, not just non-function
1168 members. It is used for ambiguity checking and the hidden
1169 checks. Whereas rval is only set if a proper (not hidden)
1170 non-function member is found. */
1172 const char *errstr = 0;
1174 if (name == error_mark_node
1175 || xbasetype == NULL_TREE
1176 || xbasetype == error_mark_node)
1179 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE);
1181 if (TREE_CODE (xbasetype) == TREE_BINFO)
1183 type = BINFO_TYPE (xbasetype);
1184 basetype_path = xbasetype;
1188 if (!RECORD_OR_UNION_CODE_P (TREE_CODE (xbasetype)))
1191 xbasetype = NULL_TREE;
1194 type = complete_type (type);
1196 basetype_path = TYPE_BINFO (type);
1201 #ifdef GATHER_STATISTICS
1202 n_calls_lookup_field++;
1203 #endif /* GATHER_STATISTICS */
1205 memset (&lfi, 0, sizeof (lfi));
1208 lfi.want_type = want_type;
1209 dfs_walk_all (basetype_path, &lookup_field_r, NULL, &lfi);
1211 rval_binfo = lfi.rval_binfo;
1213 type = BINFO_TYPE (rval_binfo);
1214 errstr = lfi.errstr;
1216 /* If we are not interested in ambiguities, don't report them;
1217 just return NULL_TREE. */
1218 if (!protect && lfi.ambiguous)
1224 return lfi.ambiguous;
1231 In the case of overloaded function names, access control is
1232 applied to the function selected by overloaded resolution.
1234 We cannot check here, even if RVAL is only a single non-static
1235 member function, since we do not know what the "this" pointer
1238 class A { protected: void f(); };
1239 class B : public A {
1246 only the first call to "f" is valid. However, if the function is
1247 static, we can check. */
1249 && !really_overloaded_fn (rval)
1250 && !(TREE_CODE (rval) == FUNCTION_DECL
1251 && DECL_NONSTATIC_MEMBER_FUNCTION_P (rval)))
1252 perform_or_defer_access_check (basetype_path, rval, rval);
1254 if (errstr && protect)
1256 if (complain & tf_error)
1258 error (errstr, name, type);
1260 print_candidates (lfi.ambiguous);
1262 rval = error_mark_node;
1265 if (rval && is_overloaded_fn (rval))
1266 rval = build_baselink (rval_binfo, basetype_path, rval,
1267 (IDENTIFIER_TYPENAME_P (name)
1268 ? TREE_TYPE (name): NULL_TREE));
1272 /* Like lookup_member, except that if we find a function member we
1273 return NULL_TREE. */
1276 lookup_field (tree xbasetype, tree name, int protect, bool want_type)
1278 tree rval = lookup_member (xbasetype, name, protect, want_type,
1279 tf_warning_or_error);
1281 /* Ignore functions, but propagate the ambiguity list. */
1282 if (!error_operand_p (rval)
1283 && (rval && BASELINK_P (rval)))
1289 /* Like lookup_member, except that if we find a non-function member we
1290 return NULL_TREE. */
1293 lookup_fnfields (tree xbasetype, tree name, int protect)
1295 tree rval = lookup_member (xbasetype, name, protect, /*want_type=*/false,
1296 tf_warning_or_error);
1298 /* Ignore non-functions, but propagate the ambiguity list. */
1299 if (!error_operand_p (rval)
1300 && (rval && !BASELINK_P (rval)))
1306 /* Return the index in the CLASSTYPE_METHOD_VEC for CLASS_TYPE
1307 corresponding to "operator TYPE ()", or -1 if there is no such
1308 operator. Only CLASS_TYPE itself is searched; this routine does
1309 not scan the base classes of CLASS_TYPE. */
1312 lookup_conversion_operator (tree class_type, tree type)
1316 if (TYPE_HAS_CONVERSION (class_type))
1320 VEC(tree,gc) *methods = CLASSTYPE_METHOD_VEC (class_type);
1322 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
1323 VEC_iterate (tree, methods, i, fn); ++i)
1325 /* All the conversion operators come near the beginning of
1326 the class. Therefore, if FN is not a conversion
1327 operator, there is no matching conversion operator in
1329 fn = OVL_CURRENT (fn);
1330 if (!DECL_CONV_FN_P (fn))
1333 if (TREE_CODE (fn) == TEMPLATE_DECL)
1334 /* All the templated conversion functions are on the same
1335 slot, so remember it. */
1337 else if (same_type_p (DECL_CONV_FN_TYPE (fn), type))
1345 /* TYPE is a class type. Return the index of the fields within
1346 the method vector with name NAME, or -1 if no such field exists.
1347 Does not lazily declare implicitly-declared member functions. */
1350 lookup_fnfields_idx_nolazy (tree type, tree name)
1352 VEC(tree,gc) *method_vec;
1357 if (!CLASS_TYPE_P (type))
1360 method_vec = CLASSTYPE_METHOD_VEC (type);
1364 #ifdef GATHER_STATISTICS
1365 n_calls_lookup_fnfields_1++;
1366 #endif /* GATHER_STATISTICS */
1368 /* Constructors are first... */
1369 if (name == ctor_identifier)
1371 fn = CLASSTYPE_CONSTRUCTORS (type);
1372 return fn ? CLASSTYPE_CONSTRUCTOR_SLOT : -1;
1374 /* and destructors are second. */
1375 if (name == dtor_identifier)
1377 fn = CLASSTYPE_DESTRUCTORS (type);
1378 return fn ? CLASSTYPE_DESTRUCTOR_SLOT : -1;
1380 if (IDENTIFIER_TYPENAME_P (name))
1381 return lookup_conversion_operator (type, TREE_TYPE (name));
1383 /* Skip the conversion operators. */
1384 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
1385 VEC_iterate (tree, method_vec, i, fn);
1387 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1390 /* If the type is complete, use binary search. */
1391 if (COMPLETE_TYPE_P (type))
1397 hi = VEC_length (tree, method_vec);
1402 #ifdef GATHER_STATISTICS
1403 n_outer_fields_searched++;
1404 #endif /* GATHER_STATISTICS */
1406 tmp = VEC_index (tree, method_vec, i);
1407 tmp = DECL_NAME (OVL_CURRENT (tmp));
1410 else if (tmp < name)
1417 for (; VEC_iterate (tree, method_vec, i, fn); ++i)
1419 #ifdef GATHER_STATISTICS
1420 n_outer_fields_searched++;
1421 #endif /* GATHER_STATISTICS */
1422 if (DECL_NAME (OVL_CURRENT (fn)) == name)
1429 /* TYPE is a class type. Return the index of the fields within
1430 the method vector with name NAME, or -1 if no such field exists. */
1433 lookup_fnfields_1 (tree type, tree name)
1435 if (!CLASS_TYPE_P (type))
1438 if (COMPLETE_TYPE_P (type))
1440 if ((name == ctor_identifier
1441 || name == base_ctor_identifier
1442 || name == complete_ctor_identifier))
1444 if (CLASSTYPE_LAZY_DEFAULT_CTOR (type))
1445 lazily_declare_fn (sfk_constructor, type);
1446 if (CLASSTYPE_LAZY_COPY_CTOR (type))
1447 lazily_declare_fn (sfk_copy_constructor, type);
1448 if (CLASSTYPE_LAZY_MOVE_CTOR (type))
1449 lazily_declare_fn (sfk_move_constructor, type);
1451 else if (name == ansi_assopname (NOP_EXPR))
1453 if (CLASSTYPE_LAZY_COPY_ASSIGN (type))
1454 lazily_declare_fn (sfk_copy_assignment, type);
1455 if (CLASSTYPE_LAZY_MOVE_ASSIGN (type))
1456 lazily_declare_fn (sfk_move_assignment, type);
1458 else if ((name == dtor_identifier
1459 || name == base_dtor_identifier
1460 || name == complete_dtor_identifier
1461 || name == deleting_dtor_identifier)
1462 && CLASSTYPE_LAZY_DESTRUCTOR (type))
1463 lazily_declare_fn (sfk_destructor, type);
1466 return lookup_fnfields_idx_nolazy (type, name);
1469 /* TYPE is a class type. Return the field within the method vector with
1470 name NAME, or NULL_TREE if no such field exists. */
1473 lookup_fnfields_slot (tree type, tree name)
1475 int ix = lookup_fnfields_1 (complete_type (type), name);
1478 return VEC_index (tree, CLASSTYPE_METHOD_VEC (type), ix);
1481 /* As above, but avoid lazily declaring functions. */
1484 lookup_fnfields_slot_nolazy (tree type, tree name)
1486 int ix = lookup_fnfields_idx_nolazy (complete_type (type), name);
1489 return VEC_index (tree, CLASSTYPE_METHOD_VEC (type), ix);
1492 /* Like lookup_fnfields_1, except that the name is extracted from
1493 FUNCTION, which is a FUNCTION_DECL or a TEMPLATE_DECL. */
1496 class_method_index_for_fn (tree class_type, tree function)
1498 gcc_assert (TREE_CODE (function) == FUNCTION_DECL
1499 || DECL_FUNCTION_TEMPLATE_P (function));
1501 return lookup_fnfields_1 (class_type,
1502 DECL_CONSTRUCTOR_P (function) ? ctor_identifier :
1503 DECL_DESTRUCTOR_P (function) ? dtor_identifier :
1504 DECL_NAME (function));
1508 /* DECL is the result of a qualified name lookup. QUALIFYING_SCOPE is
1509 the class or namespace used to qualify the name. CONTEXT_CLASS is
1510 the class corresponding to the object in which DECL will be used.
1511 Return a possibly modified version of DECL that takes into account
1514 In particular, consider an expression like `B::m' in the context of
1515 a derived class `D'. If `B::m' has been resolved to a BASELINK,
1516 then the most derived class indicated by the BASELINK_BINFO will be
1517 `B', not `D'. This function makes that adjustment. */
1520 adjust_result_of_qualified_name_lookup (tree decl,
1521 tree qualifying_scope,
1524 if (context_class && context_class != error_mark_node
1525 && CLASS_TYPE_P (context_class)
1526 && CLASS_TYPE_P (qualifying_scope)
1527 && DERIVED_FROM_P (qualifying_scope, context_class)
1528 && BASELINK_P (decl))
1532 /* Look for the QUALIFYING_SCOPE as a base of the CONTEXT_CLASS.
1533 Because we do not yet know which function will be chosen by
1534 overload resolution, we cannot yet check either accessibility
1535 or ambiguity -- in either case, the choice of a static member
1536 function might make the usage valid. */
1537 base = lookup_base (context_class, qualifying_scope,
1538 ba_unique | ba_quiet, NULL);
1541 BASELINK_ACCESS_BINFO (decl) = base;
1542 BASELINK_BINFO (decl)
1543 = lookup_base (base, BINFO_TYPE (BASELINK_BINFO (decl)),
1544 ba_unique | ba_quiet,
1553 /* Walk the class hierarchy within BINFO, in a depth-first traversal.
1554 PRE_FN is called in preorder, while POST_FN is called in postorder.
1555 If PRE_FN returns DFS_SKIP_BASES, child binfos will not be
1556 walked. If PRE_FN or POST_FN returns a different non-NULL value,
1557 that value is immediately returned and the walk is terminated. One
1558 of PRE_FN and POST_FN can be NULL. At each node, PRE_FN and
1559 POST_FN are passed the binfo to examine and the caller's DATA
1560 value. All paths are walked, thus virtual and morally virtual
1561 binfos can be multiply walked. */
1564 dfs_walk_all (tree binfo, tree (*pre_fn) (tree, void *),
1565 tree (*post_fn) (tree, void *), void *data)
1571 /* Call the pre-order walking function. */
1574 rval = pre_fn (binfo, data);
1577 if (rval == dfs_skip_bases)
1583 /* Find the next child binfo to walk. */
1584 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1586 rval = dfs_walk_all (base_binfo, pre_fn, post_fn, data);
1592 /* Call the post-order walking function. */
1595 rval = post_fn (binfo, data);
1596 gcc_assert (rval != dfs_skip_bases);
1603 /* Worker for dfs_walk_once. This behaves as dfs_walk_all, except
1604 that binfos are walked at most once. */
1607 dfs_walk_once_r (tree binfo, tree (*pre_fn) (tree, void *),
1608 tree (*post_fn) (tree, void *), void *data)
1614 /* Call the pre-order walking function. */
1617 rval = pre_fn (binfo, data);
1620 if (rval == dfs_skip_bases)
1627 /* Find the next child binfo to walk. */
1628 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1630 if (BINFO_VIRTUAL_P (base_binfo))
1632 if (BINFO_MARKED (base_binfo))
1634 BINFO_MARKED (base_binfo) = 1;
1637 rval = dfs_walk_once_r (base_binfo, pre_fn, post_fn, data);
1643 /* Call the post-order walking function. */
1646 rval = post_fn (binfo, data);
1647 gcc_assert (rval != dfs_skip_bases);
1654 /* Worker for dfs_walk_once. Recursively unmark the virtual base binfos of
1658 dfs_unmark_r (tree binfo)
1663 /* Process the basetypes. */
1664 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1666 if (BINFO_VIRTUAL_P (base_binfo))
1668 if (!BINFO_MARKED (base_binfo))
1670 BINFO_MARKED (base_binfo) = 0;
1672 /* Only walk, if it can contain more virtual bases. */
1673 if (CLASSTYPE_VBASECLASSES (BINFO_TYPE (base_binfo)))
1674 dfs_unmark_r (base_binfo);
1678 /* Like dfs_walk_all, except that binfos are not multiply walked. For
1679 non-diamond shaped hierarchies this is the same as dfs_walk_all.
1680 For diamond shaped hierarchies we must mark the virtual bases, to
1681 avoid multiple walks. */
1684 dfs_walk_once (tree binfo, tree (*pre_fn) (tree, void *),
1685 tree (*post_fn) (tree, void *), void *data)
1687 static int active = 0; /* We must not be called recursively. */
1690 gcc_assert (pre_fn || post_fn);
1691 gcc_assert (!active);
1694 if (!CLASSTYPE_DIAMOND_SHAPED_P (BINFO_TYPE (binfo)))
1695 /* We are not diamond shaped, and therefore cannot encounter the
1696 same binfo twice. */
1697 rval = dfs_walk_all (binfo, pre_fn, post_fn, data);
1700 rval = dfs_walk_once_r (binfo, pre_fn, post_fn, data);
1701 if (!BINFO_INHERITANCE_CHAIN (binfo))
1703 /* We are at the top of the hierarchy, and can use the
1704 CLASSTYPE_VBASECLASSES list for unmarking the virtual
1706 VEC(tree,gc) *vbases;
1710 for (vbases = CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)), ix = 0;
1711 VEC_iterate (tree, vbases, ix, base_binfo); ix++)
1712 BINFO_MARKED (base_binfo) = 0;
1715 dfs_unmark_r (binfo);
1723 /* Worker function for dfs_walk_once_accessible. Behaves like
1724 dfs_walk_once_r, except (a) FRIENDS_P is true if special
1725 access given by the current context should be considered, (b) ONCE
1726 indicates whether bases should be marked during traversal. */
1729 dfs_walk_once_accessible_r (tree binfo, bool friends_p, bool once,
1730 tree (*pre_fn) (tree, void *),
1731 tree (*post_fn) (tree, void *), void *data)
1733 tree rval = NULL_TREE;
1737 /* Call the pre-order walking function. */
1740 rval = pre_fn (binfo, data);
1743 if (rval == dfs_skip_bases)
1750 /* Find the next child binfo to walk. */
1751 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1753 bool mark = once && BINFO_VIRTUAL_P (base_binfo);
1755 if (mark && BINFO_MARKED (base_binfo))
1758 /* If the base is inherited via private or protected
1759 inheritance, then we can't see it, unless we are a friend of
1760 the current binfo. */
1761 if (BINFO_BASE_ACCESS (binfo, ix) != access_public_node)
1766 scope = current_scope ();
1768 || TREE_CODE (scope) == NAMESPACE_DECL
1769 || !is_friend (BINFO_TYPE (binfo), scope))
1774 BINFO_MARKED (base_binfo) = 1;
1776 rval = dfs_walk_once_accessible_r (base_binfo, friends_p, once,
1777 pre_fn, post_fn, data);
1783 /* Call the post-order walking function. */
1786 rval = post_fn (binfo, data);
1787 gcc_assert (rval != dfs_skip_bases);
1794 /* Like dfs_walk_once except that only accessible bases are walked.
1795 FRIENDS_P indicates whether friendship of the local context
1796 should be considered when determining accessibility. */
1799 dfs_walk_once_accessible (tree binfo, bool friends_p,
1800 tree (*pre_fn) (tree, void *),
1801 tree (*post_fn) (tree, void *), void *data)
1803 bool diamond_shaped = CLASSTYPE_DIAMOND_SHAPED_P (BINFO_TYPE (binfo));
1804 tree rval = dfs_walk_once_accessible_r (binfo, friends_p, diamond_shaped,
1805 pre_fn, post_fn, data);
1809 if (!BINFO_INHERITANCE_CHAIN (binfo))
1811 /* We are at the top of the hierarchy, and can use the
1812 CLASSTYPE_VBASECLASSES list for unmarking the virtual
1814 VEC(tree,gc) *vbases;
1818 for (vbases = CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)), ix = 0;
1819 VEC_iterate (tree, vbases, ix, base_binfo); ix++)
1820 BINFO_MARKED (base_binfo) = 0;
1823 dfs_unmark_r (binfo);
1828 /* Check that virtual overrider OVERRIDER is acceptable for base function
1829 BASEFN. Issue diagnostic, and return zero, if unacceptable. */
1832 check_final_overrider (tree overrider, tree basefn)
1834 tree over_type = TREE_TYPE (overrider);
1835 tree base_type = TREE_TYPE (basefn);
1836 tree over_return = TREE_TYPE (over_type);
1837 tree base_return = TREE_TYPE (base_type);
1838 tree over_throw, base_throw;
1842 if (DECL_INVALID_OVERRIDER_P (overrider))
1845 if (same_type_p (base_return, over_return))
1847 else if ((CLASS_TYPE_P (over_return) && CLASS_TYPE_P (base_return))
1848 || (TREE_CODE (base_return) == TREE_CODE (over_return)
1849 && POINTER_TYPE_P (base_return)))
1851 /* Potentially covariant. */
1852 unsigned base_quals, over_quals;
1854 fail = !POINTER_TYPE_P (base_return);
1857 fail = cp_type_quals (base_return) != cp_type_quals (over_return);
1859 base_return = TREE_TYPE (base_return);
1860 over_return = TREE_TYPE (over_return);
1862 base_quals = cp_type_quals (base_return);
1863 over_quals = cp_type_quals (over_return);
1865 if ((base_quals & over_quals) != over_quals)
1868 if (CLASS_TYPE_P (base_return) && CLASS_TYPE_P (over_return))
1870 /* Strictly speaking, the standard requires the return type to be
1871 complete even if it only differs in cv-quals, but that seems
1872 like a bug in the wording. */
1873 if (!same_type_ignoring_top_level_qualifiers_p (base_return, over_return))
1875 tree binfo = lookup_base (over_return, base_return,
1876 ba_check | ba_quiet, NULL);
1883 && can_convert (TREE_TYPE (base_type), TREE_TYPE (over_type)))
1884 /* GNU extension, allow trivial pointer conversions such as
1885 converting to void *, or qualification conversion. */
1887 /* can_convert will permit user defined conversion from a
1888 (reference to) class type. We must reject them. */
1889 over_return = non_reference (TREE_TYPE (over_type));
1890 if (CLASS_TYPE_P (over_return))
1894 warning (0, "deprecated covariant return type for %q+#D",
1896 warning (0, " overriding %q+#D", basefn);
1910 error ("invalid covariant return type for %q+#D", overrider);
1911 error (" overriding %q+#D", basefn);
1915 error ("conflicting return type specified for %q+#D", overrider);
1916 error (" overriding %q+#D", basefn);
1918 DECL_INVALID_OVERRIDER_P (overrider) = 1;
1922 /* Check throw specifier is at least as strict. */
1923 maybe_instantiate_noexcept (basefn);
1924 maybe_instantiate_noexcept (overrider);
1925 base_throw = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (basefn));
1926 over_throw = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (overrider));
1928 if (!comp_except_specs (base_throw, over_throw, ce_derived))
1930 error ("looser throw specifier for %q+#F", overrider);
1931 error (" overriding %q+#F", basefn);
1932 DECL_INVALID_OVERRIDER_P (overrider) = 1;
1936 /* Check for conflicting type attributes. */
1937 if (!comp_type_attributes (over_type, base_type))
1939 error ("conflicting type attributes specified for %q+#D", overrider);
1940 error (" overriding %q+#D", basefn);
1941 DECL_INVALID_OVERRIDER_P (overrider) = 1;
1945 if (DECL_DELETED_FN (basefn) != DECL_DELETED_FN (overrider))
1947 if (DECL_DELETED_FN (overrider))
1949 error ("deleted function %q+D", overrider);
1950 error ("overriding non-deleted function %q+D", basefn);
1951 maybe_explain_implicit_delete (overrider);
1955 error ("non-deleted function %q+D", overrider);
1956 error ("overriding deleted function %q+D", basefn);
1960 if (DECL_FINAL_P (basefn))
1962 error ("virtual function %q+D", overrider);
1963 error ("overriding final function %q+D", basefn);
1969 /* Given a class TYPE, and a function decl FNDECL, look for
1970 virtual functions in TYPE's hierarchy which FNDECL overrides.
1971 We do not look in TYPE itself, only its bases.
1973 Returns nonzero, if we find any. Set FNDECL's DECL_VIRTUAL_P, if we
1974 find that it overrides anything.
1976 We check that every function which is overridden, is correctly
1980 look_for_overrides (tree type, tree fndecl)
1982 tree binfo = TYPE_BINFO (type);
1987 /* A constructor for a class T does not override a function T
1989 if (DECL_CONSTRUCTOR_P (fndecl))
1992 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1994 tree basetype = BINFO_TYPE (base_binfo);
1996 if (TYPE_POLYMORPHIC_P (basetype))
1997 found += look_for_overrides_r (basetype, fndecl);
2002 /* Look in TYPE for virtual functions with the same signature as
2006 look_for_overrides_here (tree type, tree fndecl)
2010 /* If there are no methods in TYPE (meaning that only implicitly
2011 declared methods will ever be provided for TYPE), then there are
2012 no virtual functions. */
2013 if (!CLASSTYPE_METHOD_VEC (type))
2016 if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fndecl))
2017 ix = CLASSTYPE_DESTRUCTOR_SLOT;
2019 ix = lookup_fnfields_1 (type, DECL_NAME (fndecl));
2022 tree fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (type), ix);
2024 for (; fns; fns = OVL_NEXT (fns))
2026 tree fn = OVL_CURRENT (fns);
2028 if (!DECL_VIRTUAL_P (fn))
2029 /* Not a virtual. */;
2030 else if (DECL_CONTEXT (fn) != type)
2031 /* Introduced with a using declaration. */;
2032 else if (DECL_STATIC_FUNCTION_P (fndecl))
2034 tree btypes = TYPE_ARG_TYPES (TREE_TYPE (fn));
2035 tree dtypes = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
2036 if (compparms (TREE_CHAIN (btypes), dtypes))
2039 else if (same_signature_p (fndecl, fn))
2046 /* Look in TYPE for virtual functions overridden by FNDECL. Check both
2047 TYPE itself and its bases. */
2050 look_for_overrides_r (tree type, tree fndecl)
2052 tree fn = look_for_overrides_here (type, fndecl);
2055 if (DECL_STATIC_FUNCTION_P (fndecl))
2057 /* A static member function cannot match an inherited
2058 virtual member function. */
2059 error ("%q+#D cannot be declared", fndecl);
2060 error (" since %q+#D declared in base class", fn);
2064 /* It's definitely virtual, even if not explicitly set. */
2065 DECL_VIRTUAL_P (fndecl) = 1;
2066 check_final_overrider (fndecl, fn);
2071 /* We failed to find one declared in this class. Look in its bases. */
2072 return look_for_overrides (type, fndecl);
2075 /* Called via dfs_walk from dfs_get_pure_virtuals. */
2078 dfs_get_pure_virtuals (tree binfo, void *data)
2080 tree type = (tree) data;
2082 /* We're not interested in primary base classes; the derived class
2083 of which they are a primary base will contain the information we
2085 if (!BINFO_PRIMARY_P (binfo))
2089 for (virtuals = BINFO_VIRTUALS (binfo);
2091 virtuals = TREE_CHAIN (virtuals))
2092 if (DECL_PURE_VIRTUAL_P (BV_FN (virtuals)))
2093 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (type),
2100 /* Set CLASSTYPE_PURE_VIRTUALS for TYPE. */
2103 get_pure_virtuals (tree type)
2105 /* Clear the CLASSTYPE_PURE_VIRTUALS list; whatever is already there
2106 is going to be overridden. */
2107 CLASSTYPE_PURE_VIRTUALS (type) = NULL;
2108 /* Now, run through all the bases which are not primary bases, and
2109 collect the pure virtual functions. We look at the vtable in
2110 each class to determine what pure virtual functions are present.
2111 (A primary base is not interesting because the derived class of
2112 which it is a primary base will contain vtable entries for the
2113 pure virtuals in the base class. */
2114 dfs_walk_once (TYPE_BINFO (type), NULL, dfs_get_pure_virtuals, type);
2117 /* Debug info for C++ classes can get very large; try to avoid
2118 emitting it everywhere.
2120 Note that this optimization wins even when the target supports
2121 BINCL (if only slightly), and reduces the amount of work for the
2125 maybe_suppress_debug_info (tree t)
2127 if (write_symbols == NO_DEBUG)
2130 /* We might have set this earlier in cp_finish_decl. */
2131 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 0;
2133 /* Always emit the information for each class every time. */
2134 if (flag_emit_class_debug_always)
2137 /* If we already know how we're handling this class, handle debug info
2139 if (CLASSTYPE_INTERFACE_KNOWN (t))
2141 if (CLASSTYPE_INTERFACE_ONLY (t))
2142 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 1;
2143 /* else don't set it. */
2145 /* If the class has a vtable, write out the debug info along with
2147 else if (TYPE_CONTAINS_VPTR_P (t))
2148 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 1;
2150 /* Otherwise, just emit the debug info normally. */
2153 /* Note that we want debugging information for a base class of a class
2154 whose vtable is being emitted. Normally, this would happen because
2155 calling the constructor for a derived class implies calling the
2156 constructors for all bases, which involve initializing the
2157 appropriate vptr with the vtable for the base class; but in the
2158 presence of optimization, this initialization may be optimized
2159 away, so we tell finish_vtable_vardecl that we want the debugging
2160 information anyway. */
2163 dfs_debug_mark (tree binfo, void *data ATTRIBUTE_UNUSED)
2165 tree t = BINFO_TYPE (binfo);
2167 if (CLASSTYPE_DEBUG_REQUESTED (t))
2168 return dfs_skip_bases;
2170 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
2175 /* Write out the debugging information for TYPE, whose vtable is being
2176 emitted. Also walk through our bases and note that we want to
2177 write out information for them. This avoids the problem of not
2178 writing any debug info for intermediate basetypes whose
2179 constructors, and thus the references to their vtables, and thus
2180 the vtables themselves, were optimized away. */
2183 note_debug_info_needed (tree type)
2185 if (TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type)))
2187 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type)) = 0;
2188 rest_of_type_compilation (type, toplevel_bindings_p ());
2191 dfs_walk_all (TYPE_BINFO (type), dfs_debug_mark, NULL, 0);
2195 print_search_statistics (void)
2197 #ifdef GATHER_STATISTICS
2198 fprintf (stderr, "%d fields searched in %d[%d] calls to lookup_field[_1]\n",
2199 n_fields_searched, n_calls_lookup_field, n_calls_lookup_field_1);
2200 fprintf (stderr, "%d fnfields searched in %d calls to lookup_fnfields\n",
2201 n_outer_fields_searched, n_calls_lookup_fnfields);
2202 fprintf (stderr, "%d calls to get_base_type\n", n_calls_get_base_type);
2203 #else /* GATHER_STATISTICS */
2204 fprintf (stderr, "no search statistics\n");
2205 #endif /* GATHER_STATISTICS */
2209 reinit_search_statistics (void)
2211 #ifdef GATHER_STATISTICS
2212 n_fields_searched = 0;
2213 n_calls_lookup_field = 0, n_calls_lookup_field_1 = 0;
2214 n_calls_lookup_fnfields = 0, n_calls_lookup_fnfields_1 = 0;
2215 n_calls_get_base_type = 0;
2216 n_outer_fields_searched = 0;
2217 n_contexts_saved = 0;
2218 #endif /* GATHER_STATISTICS */
2221 /* Helper for lookup_conversions_r. TO_TYPE is the type converted to
2222 by a conversion op in base BINFO. VIRTUAL_DEPTH is nonzero if
2223 BINFO is morally virtual, and VIRTUALNESS is nonzero if virtual
2224 bases have been encountered already in the tree walk. PARENT_CONVS
2225 is the list of lists of conversion functions that could hide CONV
2226 and OTHER_CONVS is the list of lists of conversion functions that
2227 could hide or be hidden by CONV, should virtualness be involved in
2228 the hierarchy. Merely checking the conversion op's name is not
2229 enough because two conversion operators to the same type can have
2230 different names. Return nonzero if we are visible. */
2233 check_hidden_convs (tree binfo, int virtual_depth, int virtualness,
2234 tree to_type, tree parent_convs, tree other_convs)
2238 /* See if we are hidden by a parent conversion. */
2239 for (level = parent_convs; level; level = TREE_CHAIN (level))
2240 for (probe = TREE_VALUE (level); probe; probe = TREE_CHAIN (probe))
2241 if (same_type_p (to_type, TREE_TYPE (probe)))
2244 if (virtual_depth || virtualness)
2246 /* In a virtual hierarchy, we could be hidden, or could hide a
2247 conversion function on the other_convs list. */
2248 for (level = other_convs; level; level = TREE_CHAIN (level))
2254 if (!(virtual_depth || TREE_STATIC (level)))
2255 /* Neither is morally virtual, so cannot hide each other. */
2258 if (!TREE_VALUE (level))
2259 /* They evaporated away already. */
2262 they_hide_us = (virtual_depth
2263 && original_binfo (binfo, TREE_PURPOSE (level)));
2264 we_hide_them = (!they_hide_us && TREE_STATIC (level)
2265 && original_binfo (TREE_PURPOSE (level), binfo));
2267 if (!(we_hide_them || they_hide_us))
2268 /* Neither is within the other, so no hiding can occur. */
2271 for (prev = &TREE_VALUE (level), other = *prev; other;)
2273 if (same_type_p (to_type, TREE_TYPE (other)))
2276 /* We are hidden. */
2281 /* We hide the other one. */
2282 other = TREE_CHAIN (other);
2287 prev = &TREE_CHAIN (other);
2295 /* Helper for lookup_conversions_r. PARENT_CONVS is a list of lists
2296 of conversion functions, the first slot will be for the current
2297 binfo, if MY_CONVS is non-NULL. CHILD_CONVS is the list of lists
2298 of conversion functions from children of the current binfo,
2299 concatenated with conversions from elsewhere in the hierarchy --
2300 that list begins with OTHER_CONVS. Return a single list of lists
2301 containing only conversions from the current binfo and its
2305 split_conversions (tree my_convs, tree parent_convs,
2306 tree child_convs, tree other_convs)
2311 /* Remove the original other_convs portion from child_convs. */
2312 for (prev = NULL, t = child_convs;
2313 t != other_convs; prev = t, t = TREE_CHAIN (t))
2317 TREE_CHAIN (prev) = NULL_TREE;
2319 child_convs = NULL_TREE;
2321 /* Attach the child convs to any we had at this level. */
2324 my_convs = parent_convs;
2325 TREE_CHAIN (my_convs) = child_convs;
2328 my_convs = child_convs;
2333 /* Worker for lookup_conversions. Lookup conversion functions in
2334 BINFO and its children. VIRTUAL_DEPTH is nonzero, if BINFO is in
2335 a morally virtual base, and VIRTUALNESS is nonzero, if we've
2336 encountered virtual bases already in the tree walk. PARENT_CONVS &
2337 PARENT_TPL_CONVS are lists of list of conversions within parent
2338 binfos. OTHER_CONVS and OTHER_TPL_CONVS are conversions found
2339 elsewhere in the tree. Return the conversions found within this
2340 portion of the graph in CONVS and TPL_CONVS. Return nonzero is we
2341 encountered virtualness. We keep template and non-template
2342 conversions separate, to avoid unnecessary type comparisons.
2344 The located conversion functions are held in lists of lists. The
2345 TREE_VALUE of the outer list is the list of conversion functions
2346 found in a particular binfo. The TREE_PURPOSE of both the outer
2347 and inner lists is the binfo at which those conversions were
2348 found. TREE_STATIC is set for those lists within of morally
2349 virtual binfos. The TREE_VALUE of the inner list is the conversion
2350 function or overload itself. The TREE_TYPE of each inner list node
2351 is the converted-to type. */
2354 lookup_conversions_r (tree binfo,
2355 int virtual_depth, int virtualness,
2356 tree parent_convs, tree parent_tpl_convs,
2357 tree other_convs, tree other_tpl_convs,
2358 tree *convs, tree *tpl_convs)
2360 int my_virtualness = 0;
2361 tree my_convs = NULL_TREE;
2362 tree my_tpl_convs = NULL_TREE;
2363 tree child_convs = NULL_TREE;
2364 tree child_tpl_convs = NULL_TREE;
2367 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (BINFO_TYPE (binfo));
2370 /* If we have no conversion operators, then don't look. */
2371 if (!TYPE_HAS_CONVERSION (BINFO_TYPE (binfo)))
2373 *convs = *tpl_convs = NULL_TREE;
2378 if (BINFO_VIRTUAL_P (binfo))
2381 /* First, locate the unhidden ones at this level. */
2382 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2383 VEC_iterate (tree, method_vec, i, conv);
2386 tree cur = OVL_CURRENT (conv);
2388 if (!DECL_CONV_FN_P (cur))
2391 if (TREE_CODE (cur) == TEMPLATE_DECL)
2393 /* Only template conversions can be overloaded, and we must
2394 flatten them out and check each one individually. */
2397 for (tpls = conv; tpls; tpls = OVL_NEXT (tpls))
2399 tree tpl = OVL_CURRENT (tpls);
2400 tree type = DECL_CONV_FN_TYPE (tpl);
2402 if (check_hidden_convs (binfo, virtual_depth, virtualness,
2403 type, parent_tpl_convs, other_tpl_convs))
2405 my_tpl_convs = tree_cons (binfo, tpl, my_tpl_convs);
2406 TREE_TYPE (my_tpl_convs) = type;
2409 TREE_STATIC (my_tpl_convs) = 1;
2417 tree name = DECL_NAME (cur);
2419 if (!IDENTIFIER_MARKED (name))
2421 tree type = DECL_CONV_FN_TYPE (cur);
2423 if (check_hidden_convs (binfo, virtual_depth, virtualness,
2424 type, parent_convs, other_convs))
2426 my_convs = tree_cons (binfo, conv, my_convs);
2427 TREE_TYPE (my_convs) = type;
2430 TREE_STATIC (my_convs) = 1;
2433 IDENTIFIER_MARKED (name) = 1;
2441 parent_convs = tree_cons (binfo, my_convs, parent_convs);
2443 TREE_STATIC (parent_convs) = 1;
2448 parent_tpl_convs = tree_cons (binfo, my_tpl_convs, parent_tpl_convs);
2450 TREE_STATIC (parent_tpl_convs) = 1;
2453 child_convs = other_convs;
2454 child_tpl_convs = other_tpl_convs;
2456 /* Now iterate over each base, looking for more conversions. */
2457 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
2459 tree base_convs, base_tpl_convs;
2460 unsigned base_virtualness;
2462 base_virtualness = lookup_conversions_r (base_binfo,
2463 virtual_depth, virtualness,
2464 parent_convs, parent_tpl_convs,
2465 child_convs, child_tpl_convs,
2466 &base_convs, &base_tpl_convs);
2467 if (base_virtualness)
2468 my_virtualness = virtualness = 1;
2469 child_convs = chainon (base_convs, child_convs);
2470 child_tpl_convs = chainon (base_tpl_convs, child_tpl_convs);
2473 /* Unmark the conversions found at this level */
2474 for (conv = my_convs; conv; conv = TREE_CHAIN (conv))
2475 IDENTIFIER_MARKED (DECL_NAME (OVL_CURRENT (TREE_VALUE (conv)))) = 0;
2477 *convs = split_conversions (my_convs, parent_convs,
2478 child_convs, other_convs);
2479 *tpl_convs = split_conversions (my_tpl_convs, parent_tpl_convs,
2480 child_tpl_convs, other_tpl_convs);
2482 return my_virtualness;
2485 /* Return a TREE_LIST containing all the non-hidden user-defined
2486 conversion functions for TYPE (and its base-classes). The
2487 TREE_VALUE of each node is the FUNCTION_DECL of the conversion
2488 function. The TREE_PURPOSE is the BINFO from which the conversion
2489 functions in this node were selected. This function is effectively
2490 performing a set of member lookups as lookup_fnfield does, but
2491 using the type being converted to as the unique key, rather than the
2495 lookup_conversions (tree type)
2497 tree convs, tpl_convs;
2498 tree list = NULL_TREE;
2500 complete_type (type);
2501 if (!TYPE_BINFO (type))
2504 lookup_conversions_r (TYPE_BINFO (type), 0, 0,
2505 NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE,
2506 &convs, &tpl_convs);
2508 /* Flatten the list-of-lists */
2509 for (; convs; convs = TREE_CHAIN (convs))
2513 for (probe = TREE_VALUE (convs); probe; probe = next)
2515 next = TREE_CHAIN (probe);
2517 TREE_CHAIN (probe) = list;
2522 for (; tpl_convs; tpl_convs = TREE_CHAIN (tpl_convs))
2526 for (probe = TREE_VALUE (tpl_convs); probe; probe = next)
2528 next = TREE_CHAIN (probe);
2530 TREE_CHAIN (probe) = list;
2538 /* Returns the binfo of the first direct or indirect virtual base derived
2539 from BINFO, or NULL if binfo is not via virtual. */
2542 binfo_from_vbase (tree binfo)
2544 for (; binfo; binfo = BINFO_INHERITANCE_CHAIN (binfo))
2546 if (BINFO_VIRTUAL_P (binfo))
2552 /* Returns the binfo of the first direct or indirect virtual base derived
2553 from BINFO up to the TREE_TYPE, LIMIT, or NULL if binfo is not
2557 binfo_via_virtual (tree binfo, tree limit)
2559 if (limit && !CLASSTYPE_VBASECLASSES (limit))
2560 /* LIMIT has no virtual bases, so BINFO cannot be via one. */
2563 for (; binfo && !SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), limit);
2564 binfo = BINFO_INHERITANCE_CHAIN (binfo))
2566 if (BINFO_VIRTUAL_P (binfo))
2572 /* BINFO is a base binfo in the complete type BINFO_TYPE (HERE).
2573 Find the equivalent binfo within whatever graph HERE is located.
2574 This is the inverse of original_binfo. */
2577 copied_binfo (tree binfo, tree here)
2579 tree result = NULL_TREE;
2581 if (BINFO_VIRTUAL_P (binfo))
2585 for (t = here; BINFO_INHERITANCE_CHAIN (t);
2586 t = BINFO_INHERITANCE_CHAIN (t))
2589 result = binfo_for_vbase (BINFO_TYPE (binfo), BINFO_TYPE (t));
2591 else if (BINFO_INHERITANCE_CHAIN (binfo))
2597 cbinfo = copied_binfo (BINFO_INHERITANCE_CHAIN (binfo), here);
2598 for (ix = 0; BINFO_BASE_ITERATE (cbinfo, ix, base_binfo); ix++)
2599 if (SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo), BINFO_TYPE (binfo)))
2601 result = base_binfo;
2607 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (here), BINFO_TYPE (binfo)));
2611 gcc_assert (result);
2616 binfo_for_vbase (tree base, tree t)
2620 VEC(tree,gc) *vbases;
2622 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
2623 VEC_iterate (tree, vbases, ix, binfo); ix++)
2624 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), base))
2629 /* BINFO is some base binfo of HERE, within some other
2630 hierarchy. Return the equivalent binfo, but in the hierarchy
2631 dominated by HERE. This is the inverse of copied_binfo. If BINFO
2632 is not a base binfo of HERE, returns NULL_TREE. */
2635 original_binfo (tree binfo, tree here)
2639 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (here)))
2641 else if (BINFO_VIRTUAL_P (binfo))
2642 result = (CLASSTYPE_VBASECLASSES (BINFO_TYPE (here))
2643 ? binfo_for_vbase (BINFO_TYPE (binfo), BINFO_TYPE (here))
2645 else if (BINFO_INHERITANCE_CHAIN (binfo))
2649 base_binfos = original_binfo (BINFO_INHERITANCE_CHAIN (binfo), here);
2655 for (ix = 0; (base_binfo = BINFO_BASE_BINFO (base_binfos, ix)); ix++)
2656 if (SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
2657 BINFO_TYPE (binfo)))
2659 result = base_binfo;