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);
445 field = TYPE_FIELDS (type);
447 #ifdef GATHER_STATISTICS
448 n_calls_lookup_field_1++;
449 #endif /* GATHER_STATISTICS */
450 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
454 #ifdef GATHER_STATISTICS
456 #endif /* GATHER_STATISTICS */
457 gcc_assert (DECL_P (field));
458 if (DECL_NAME (field) == NULL_TREE
459 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
461 tree temp = lookup_field_1 (TREE_TYPE (field), name, want_type);
466 if (TREE_CODE (decl) == USING_DECL
467 && DECL_NAME (decl) == name)
469 decl = strip_using_decl (decl);
470 if (is_overloaded_fn (decl))
474 if (DECL_NAME (decl) == name
476 || TREE_CODE (decl) == TYPE_DECL
477 || DECL_TYPE_TEMPLATE_P (decl)))
481 if (name == vptr_identifier)
483 /* Give the user what s/he thinks s/he wants. */
484 if (TYPE_POLYMORPHIC_P (type))
485 return TYPE_VFIELD (type);
490 /* Return the FUNCTION_DECL, RECORD_TYPE, UNION_TYPE, or
491 NAMESPACE_DECL corresponding to the innermost non-block scope. */
496 /* There are a number of cases we need to be aware of here:
497 current_class_type current_function_decl
504 Those last two make life interesting. If we're in a function which is
505 itself inside a class, we need decls to go into the fn's decls (our
506 second case below). But if we're in a class and the class itself is
507 inside a function, we need decls to go into the decls for the class. To
508 achieve this last goal, we must see if, when both current_class_ptr and
509 current_function_decl are set, the class was declared inside that
510 function. If so, we know to put the decls into the class's scope. */
511 if (current_function_decl && current_class_type
512 && ((DECL_FUNCTION_MEMBER_P (current_function_decl)
513 && same_type_p (DECL_CONTEXT (current_function_decl),
515 || (DECL_FRIEND_CONTEXT (current_function_decl)
516 && same_type_p (DECL_FRIEND_CONTEXT (current_function_decl),
517 current_class_type))))
518 return current_function_decl;
519 if (current_class_type)
520 return current_class_type;
521 if (current_function_decl)
522 return current_function_decl;
523 return current_namespace;
526 /* Returns nonzero if we are currently in a function scope. Note
527 that this function returns zero if we are within a local class, but
528 not within a member function body of the local class. */
531 at_function_scope_p (void)
533 tree cs = current_scope ();
534 return cs && TREE_CODE (cs) == FUNCTION_DECL;
537 /* Returns true if the innermost active scope is a class scope. */
540 at_class_scope_p (void)
542 tree cs = current_scope ();
543 return cs && TYPE_P (cs);
546 /* Returns true if the innermost active scope is a namespace scope. */
549 at_namespace_scope_p (void)
551 tree cs = current_scope ();
552 return cs && TREE_CODE (cs) == NAMESPACE_DECL;
555 /* Return the scope of DECL, as appropriate when doing name-lookup. */
558 context_for_name_lookup (tree decl)
562 For the purposes of name lookup, after the anonymous union
563 definition, the members of the anonymous union are considered to
564 have been defined in the scope in which the anonymous union is
566 tree context = DECL_CONTEXT (decl);
568 while (context && TYPE_P (context) && ANON_AGGR_TYPE_P (context))
569 context = TYPE_CONTEXT (context);
571 context = global_namespace;
576 /* The accessibility routines use BINFO_ACCESS for scratch space
577 during the computation of the accessibility of some declaration. */
579 #define BINFO_ACCESS(NODE) \
580 ((access_kind) ((TREE_PUBLIC (NODE) << 1) | TREE_PRIVATE (NODE)))
582 /* Set the access associated with NODE to ACCESS. */
584 #define SET_BINFO_ACCESS(NODE, ACCESS) \
585 ((TREE_PUBLIC (NODE) = ((ACCESS) & 2) != 0), \
586 (TREE_PRIVATE (NODE) = ((ACCESS) & 1) != 0))
588 /* Called from access_in_type via dfs_walk. Calculate the access to
589 DATA (which is really a DECL) in BINFO. */
592 dfs_access_in_type (tree binfo, void *data)
594 tree decl = (tree) data;
595 tree type = BINFO_TYPE (binfo);
596 access_kind access = ak_none;
598 if (context_for_name_lookup (decl) == type)
600 /* If we have descended to the scope of DECL, just note the
601 appropriate access. */
602 if (TREE_PRIVATE (decl))
604 else if (TREE_PROTECTED (decl))
605 access = ak_protected;
611 /* First, check for an access-declaration that gives us more
612 access to the DECL. The CONST_DECL for an enumeration
613 constant will not have DECL_LANG_SPECIFIC, and thus no
615 if (DECL_LANG_SPECIFIC (decl) && !DECL_DISCRIMINATOR_P (decl))
617 tree decl_access = purpose_member (type, DECL_ACCESS (decl));
621 decl_access = TREE_VALUE (decl_access);
623 if (decl_access == access_public_node)
625 else if (decl_access == access_protected_node)
626 access = ak_protected;
627 else if (decl_access == access_private_node)
638 VEC(tree,gc) *accesses;
640 /* Otherwise, scan our baseclasses, and pick the most favorable
642 accesses = BINFO_BASE_ACCESSES (binfo);
643 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
645 tree base_access = VEC_index (tree, accesses, i);
646 access_kind base_access_now = BINFO_ACCESS (base_binfo);
648 if (base_access_now == ak_none || base_access_now == ak_private)
649 /* If it was not accessible in the base, or only
650 accessible as a private member, we can't access it
652 base_access_now = ak_none;
653 else if (base_access == access_protected_node)
654 /* Public and protected members in the base become
656 base_access_now = ak_protected;
657 else if (base_access == access_private_node)
658 /* Public and protected members in the base become
660 base_access_now = ak_private;
662 /* See if the new access, via this base, gives more
663 access than our previous best access. */
664 if (base_access_now != ak_none
665 && (access == ak_none || base_access_now < access))
667 access = base_access_now;
669 /* If the new access is public, we can't do better. */
670 if (access == ak_public)
677 /* Note the access to DECL in TYPE. */
678 SET_BINFO_ACCESS (binfo, access);
683 /* Return the access to DECL in TYPE. */
686 access_in_type (tree type, tree decl)
688 tree binfo = TYPE_BINFO (type);
690 /* We must take into account
694 If a name can be reached by several paths through a multiple
695 inheritance graph, the access is that of the path that gives
698 The algorithm we use is to make a post-order depth-first traversal
699 of the base-class hierarchy. As we come up the tree, we annotate
700 each node with the most lenient access. */
701 dfs_walk_once (binfo, NULL, dfs_access_in_type, decl);
703 return BINFO_ACCESS (binfo);
706 /* Returns nonzero if it is OK to access DECL through an object
707 indicated by BINFO in the context of DERIVED. */
710 protected_accessible_p (tree decl, tree derived, tree binfo)
714 /* We're checking this clause from [class.access.base]
716 m as a member of N is protected, and the reference occurs in a
717 member or friend of class N, or in a member or friend of a
718 class P derived from N, where m as a member of P is public, private
721 Here DERIVED is a possible P, DECL is m and BINFO_TYPE (binfo) is N. */
723 /* If DERIVED isn't derived from N, then it can't be a P. */
724 if (!DERIVED_FROM_P (BINFO_TYPE (binfo), derived))
727 access = access_in_type (derived, decl);
729 /* If m is inaccessible in DERIVED, then it's not a P. */
730 if (access == ak_none)
735 When a friend or a member function of a derived class references
736 a protected nonstatic member of a base class, an access check
737 applies in addition to those described earlier in clause
738 _class.access_) Except when forming a pointer to member
739 (_expr.unary.op_), the access must be through a pointer to,
740 reference to, or object of the derived class itself (or any class
741 derived from that class) (_expr.ref_). If the access is to form
742 a pointer to member, the nested-name-specifier shall name the
743 derived class (or any class derived from that class). */
744 if (DECL_NONSTATIC_MEMBER_P (decl))
746 /* We can tell through what the reference is occurring by
747 chasing BINFO up to the root. */
749 while (BINFO_INHERITANCE_CHAIN (t))
750 t = BINFO_INHERITANCE_CHAIN (t);
752 if (!DERIVED_FROM_P (derived, BINFO_TYPE (t)))
759 /* Returns nonzero if SCOPE is a friend of a type which would be able
760 to access DECL through the object indicated by BINFO. */
763 friend_accessible_p (tree scope, tree decl, tree binfo)
765 tree befriending_classes;
771 if (TREE_CODE (scope) == FUNCTION_DECL
772 || DECL_FUNCTION_TEMPLATE_P (scope))
773 befriending_classes = DECL_BEFRIENDING_CLASSES (scope);
774 else if (TYPE_P (scope))
775 befriending_classes = CLASSTYPE_BEFRIENDING_CLASSES (scope);
779 for (t = befriending_classes; t; t = TREE_CHAIN (t))
780 if (protected_accessible_p (decl, TREE_VALUE (t), binfo))
783 /* Nested classes have the same access as their enclosing types, as
784 per DR 45 (this is a change from the standard). */
786 for (t = TYPE_CONTEXT (scope); t && TYPE_P (t); t = TYPE_CONTEXT (t))
787 if (protected_accessible_p (decl, t, binfo))
790 if (TREE_CODE (scope) == FUNCTION_DECL
791 || DECL_FUNCTION_TEMPLATE_P (scope))
793 /* Perhaps this SCOPE is a member of a class which is a
795 if (DECL_CLASS_SCOPE_P (scope)
796 && friend_accessible_p (DECL_CONTEXT (scope), decl, binfo))
799 /* Or an instantiation of something which is a friend. */
800 if (DECL_TEMPLATE_INFO (scope))
803 /* Increment processing_template_decl to make sure that
804 dependent_type_p works correctly. */
805 ++processing_template_decl;
806 ret = friend_accessible_p (DECL_TI_TEMPLATE (scope), decl, binfo);
807 --processing_template_decl;
815 /* Called via dfs_walk_once_accessible from accessible_p */
818 dfs_accessible_post (tree binfo, void *data ATTRIBUTE_UNUSED)
820 if (BINFO_ACCESS (binfo) != ak_none)
822 tree scope = current_scope ();
823 if (scope && TREE_CODE (scope) != NAMESPACE_DECL
824 && is_friend (BINFO_TYPE (binfo), scope))
831 /* DECL is a declaration from a base class of TYPE, which was the
832 class used to name DECL. Return nonzero if, in the current
833 context, DECL is accessible. If TYPE is actually a BINFO node,
834 then we can tell in what context the access is occurring by looking
835 at the most derived class along the path indicated by BINFO. If
836 CONSIDER_LOCAL is true, do consider special access the current
837 scope or friendship thereof we might have. */
840 accessible_p (tree type, tree decl, bool consider_local_p)
846 /* Nonzero if it's OK to access DECL if it has protected
847 accessibility in TYPE. */
848 int protected_ok = 0;
850 /* If this declaration is in a block or namespace scope, there's no
852 if (!TYPE_P (context_for_name_lookup (decl)))
855 /* There is no need to perform access checks inside a thunk. */
856 scope = current_scope ();
857 if (scope && DECL_THUNK_P (scope))
860 /* In a template declaration, we cannot be sure whether the
861 particular specialization that is instantiated will be a friend
862 or not. Therefore, all access checks are deferred until
863 instantiation. However, PROCESSING_TEMPLATE_DECL is set in the
864 parameter list for a template (because we may see dependent types
865 in default arguments for template parameters), and access
866 checking should be performed in the outermost parameter list. */
867 if (processing_template_decl
868 && (!processing_template_parmlist || processing_template_decl > 1))
874 type = BINFO_TYPE (type);
877 binfo = TYPE_BINFO (type);
879 /* [class.access.base]
881 A member m is accessible when named in class N if
883 --m as a member of N is public, or
885 --m as a member of N is private, and the reference occurs in a
886 member or friend of class N, or
888 --m as a member of N is protected, and the reference occurs in a
889 member or friend of class N, or in a member or friend of a
890 class P derived from N, where m as a member of P is private or
893 --there exists a base class B of N that is accessible at the point
894 of reference, and m is accessible when named in class B.
896 We walk the base class hierarchy, checking these conditions. */
898 if (consider_local_p)
900 /* Figure out where the reference is occurring. Check to see if
901 DECL is private or protected in this scope, since that will
902 determine whether protected access is allowed. */
903 if (current_class_type)
904 protected_ok = protected_accessible_p (decl,
905 current_class_type, binfo);
907 /* Now, loop through the classes of which we are a friend. */
909 protected_ok = friend_accessible_p (scope, decl, binfo);
912 /* Standardize the binfo that access_in_type will use. We don't
913 need to know what path was chosen from this point onwards. */
914 binfo = TYPE_BINFO (type);
916 /* Compute the accessibility of DECL in the class hierarchy
917 dominated by type. */
918 access = access_in_type (type, decl);
919 if (access == ak_public
920 || (access == ak_protected && protected_ok))
923 if (!consider_local_p)
926 /* Walk the hierarchy again, looking for a base class that allows
928 return dfs_walk_once_accessible (binfo, /*friends=*/true,
929 NULL, dfs_accessible_post, NULL)
933 struct lookup_field_info {
934 /* The type in which we're looking. */
936 /* The name of the field for which we're looking. */
938 /* If non-NULL, the current result of the lookup. */
940 /* The path to RVAL. */
942 /* If non-NULL, the lookup was ambiguous, and this is a list of the
945 /* If nonzero, we are looking for types, not data members. */
947 /* If something went wrong, a message indicating what. */
951 /* Nonzero for a class member means that it is shared between all objects
954 [class.member.lookup]:If the resulting set of declarations are not all
955 from sub-objects of the same type, or the set has a nonstatic member
956 and includes members from distinct sub-objects, there is an ambiguity
957 and the program is ill-formed.
959 This function checks that T contains no nonstatic members. */
962 shared_member_p (tree t)
964 if (TREE_CODE (t) == VAR_DECL || TREE_CODE (t) == TYPE_DECL \
965 || TREE_CODE (t) == CONST_DECL)
967 if (is_overloaded_fn (t))
970 for (; t; t = OVL_NEXT (t))
972 tree fn = OVL_CURRENT (t);
973 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
981 /* Routine to see if the sub-object denoted by the binfo PARENT can be
982 found as a base class and sub-object of the object denoted by
986 is_subobject_of_p (tree parent, tree binfo)
990 for (probe = parent; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
994 if (BINFO_VIRTUAL_P (probe))
995 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (binfo))
1001 /* DATA is really a struct lookup_field_info. Look for a field with
1002 the name indicated there in BINFO. If this function returns a
1003 non-NULL value it is the result of the lookup. Called from
1004 lookup_field via breadth_first_search. */
1007 lookup_field_r (tree binfo, void *data)
1009 struct lookup_field_info *lfi = (struct lookup_field_info *) data;
1010 tree type = BINFO_TYPE (binfo);
1011 tree nval = NULL_TREE;
1013 /* If this is a dependent base, don't look in it. */
1014 if (BINFO_DEPENDENT_BASE_P (binfo))
1017 /* If this base class is hidden by the best-known value so far, we
1018 don't need to look. */
1019 if (lfi->rval_binfo && BINFO_INHERITANCE_CHAIN (binfo) == lfi->rval_binfo
1020 && !BINFO_VIRTUAL_P (binfo))
1021 return dfs_skip_bases;
1023 /* First, look for a function. There can't be a function and a data
1024 member with the same name, and if there's a function and a type
1025 with the same name, the type is hidden by the function. */
1026 if (!lfi->want_type)
1027 nval = lookup_fnfields_slot (type, lfi->name);
1030 /* Look for a data member or type. */
1031 nval = lookup_field_1 (type, lfi->name, lfi->want_type);
1033 /* If there is no declaration with the indicated name in this type,
1034 then there's nothing to do. */
1038 /* If we're looking up a type (as with an elaborated type specifier)
1039 we ignore all non-types we find. */
1040 if (lfi->want_type && TREE_CODE (nval) != TYPE_DECL
1041 && !DECL_TYPE_TEMPLATE_P (nval))
1043 if (lfi->name == TYPE_IDENTIFIER (type))
1045 /* If the aggregate has no user defined constructors, we allow
1046 it to have fields with the same name as the enclosing type.
1047 If we are looking for that name, find the corresponding
1049 for (nval = TREE_CHAIN (nval); nval; nval = TREE_CHAIN (nval))
1050 if (DECL_NAME (nval) == lfi->name
1051 && TREE_CODE (nval) == TYPE_DECL)
1056 if (!nval && CLASSTYPE_NESTED_UTDS (type) != NULL)
1058 binding_entry e = binding_table_find (CLASSTYPE_NESTED_UTDS (type),
1061 nval = TYPE_MAIN_DECL (e->type);
1067 /* If the lookup already found a match, and the new value doesn't
1068 hide the old one, we might have an ambiguity. */
1070 && !is_subobject_of_p (lfi->rval_binfo, binfo))
1073 if (nval == lfi->rval && shared_member_p (nval))
1074 /* The two things are really the same. */
1076 else if (is_subobject_of_p (binfo, lfi->rval_binfo))
1077 /* The previous value hides the new one. */
1081 /* We have a real ambiguity. We keep a chain of all the
1083 if (!lfi->ambiguous && lfi->rval)
1085 /* This is the first time we noticed an ambiguity. Add
1086 what we previously thought was a reasonable candidate
1088 lfi->ambiguous = tree_cons (NULL_TREE, lfi->rval, NULL_TREE);
1089 TREE_TYPE (lfi->ambiguous) = error_mark_node;
1092 /* Add the new value. */
1093 lfi->ambiguous = tree_cons (NULL_TREE, nval, lfi->ambiguous);
1094 TREE_TYPE (lfi->ambiguous) = error_mark_node;
1095 lfi->errstr = G_("request for member %qD is ambiguous");
1101 lfi->rval_binfo = binfo;
1105 /* Don't look for constructors or destructors in base classes. */
1106 if (IDENTIFIER_CTOR_OR_DTOR_P (lfi->name))
1107 return dfs_skip_bases;
1111 /* Return a "baselink" with BASELINK_BINFO, BASELINK_ACCESS_BINFO,
1112 BASELINK_FUNCTIONS, and BASELINK_OPTYPE set to BINFO, ACCESS_BINFO,
1113 FUNCTIONS, and OPTYPE respectively. */
1116 build_baselink (tree binfo, tree access_binfo, tree functions, tree optype)
1120 gcc_assert (TREE_CODE (functions) == FUNCTION_DECL
1121 || TREE_CODE (functions) == TEMPLATE_DECL
1122 || TREE_CODE (functions) == TEMPLATE_ID_EXPR
1123 || TREE_CODE (functions) == OVERLOAD);
1124 gcc_assert (!optype || TYPE_P (optype));
1125 gcc_assert (TREE_TYPE (functions));
1127 baselink = make_node (BASELINK);
1128 TREE_TYPE (baselink) = TREE_TYPE (functions);
1129 BASELINK_BINFO (baselink) = binfo;
1130 BASELINK_ACCESS_BINFO (baselink) = access_binfo;
1131 BASELINK_FUNCTIONS (baselink) = functions;
1132 BASELINK_OPTYPE (baselink) = optype;
1137 /* Look for a member named NAME in an inheritance lattice dominated by
1138 XBASETYPE. If PROTECT is 0 or two, we do not check access. If it
1139 is 1, we enforce accessibility. If PROTECT is zero, then, for an
1140 ambiguous lookup, we return NULL. If PROTECT is 1, we issue error
1141 messages about inaccessible or ambiguous lookup. If PROTECT is 2,
1142 we return a TREE_LIST whose TREE_TYPE is error_mark_node and whose
1143 TREE_VALUEs are the list of ambiguous candidates.
1145 WANT_TYPE is 1 when we should only return TYPE_DECLs.
1147 If nothing can be found return NULL_TREE and do not issue an error. */
1150 lookup_member (tree xbasetype, tree name, int protect, bool want_type,
1151 tsubst_flags_t complain)
1153 tree rval, rval_binfo = NULL_TREE;
1154 tree type = NULL_TREE, basetype_path = NULL_TREE;
1155 struct lookup_field_info lfi;
1157 /* rval_binfo is the binfo associated with the found member, note,
1158 this can be set with useful information, even when rval is not
1159 set, because it must deal with ALL members, not just non-function
1160 members. It is used for ambiguity checking and the hidden
1161 checks. Whereas rval is only set if a proper (not hidden)
1162 non-function member is found. */
1164 const char *errstr = 0;
1166 if (name == error_mark_node)
1169 gcc_assert (TREE_CODE (name) == IDENTIFIER_NODE);
1171 if (TREE_CODE (xbasetype) == TREE_BINFO)
1173 type = BINFO_TYPE (xbasetype);
1174 basetype_path = xbasetype;
1178 if (!RECORD_OR_UNION_CODE_P (TREE_CODE (xbasetype)))
1181 xbasetype = NULL_TREE;
1184 type = complete_type (type);
1186 basetype_path = TYPE_BINFO (type);
1191 #ifdef GATHER_STATISTICS
1192 n_calls_lookup_field++;
1193 #endif /* GATHER_STATISTICS */
1195 memset (&lfi, 0, sizeof (lfi));
1198 lfi.want_type = want_type;
1199 dfs_walk_all (basetype_path, &lookup_field_r, NULL, &lfi);
1201 rval_binfo = lfi.rval_binfo;
1203 type = BINFO_TYPE (rval_binfo);
1204 errstr = lfi.errstr;
1206 /* If we are not interested in ambiguities, don't report them;
1207 just return NULL_TREE. */
1208 if (!protect && lfi.ambiguous)
1214 return lfi.ambiguous;
1221 In the case of overloaded function names, access control is
1222 applied to the function selected by overloaded resolution.
1224 We cannot check here, even if RVAL is only a single non-static
1225 member function, since we do not know what the "this" pointer
1228 class A { protected: void f(); };
1229 class B : public A {
1236 only the first call to "f" is valid. However, if the function is
1237 static, we can check. */
1239 && !really_overloaded_fn (rval)
1240 && !(TREE_CODE (rval) == FUNCTION_DECL
1241 && DECL_NONSTATIC_MEMBER_FUNCTION_P (rval)))
1242 perform_or_defer_access_check (basetype_path, rval, rval);
1244 if (errstr && protect)
1246 if (complain & tf_error)
1248 error (errstr, name, type);
1250 print_candidates (lfi.ambiguous);
1252 rval = error_mark_node;
1255 if (rval && is_overloaded_fn (rval))
1256 rval = build_baselink (rval_binfo, basetype_path, rval,
1257 (IDENTIFIER_TYPENAME_P (name)
1258 ? TREE_TYPE (name): NULL_TREE));
1262 /* Like lookup_member, except that if we find a function member we
1263 return NULL_TREE. */
1266 lookup_field (tree xbasetype, tree name, int protect, bool want_type)
1268 tree rval = lookup_member (xbasetype, name, protect, want_type,
1269 tf_warning_or_error);
1271 /* Ignore functions, but propagate the ambiguity list. */
1272 if (!error_operand_p (rval)
1273 && (rval && BASELINK_P (rval)))
1279 /* Like lookup_member, except that if we find a non-function member we
1280 return NULL_TREE. */
1283 lookup_fnfields (tree xbasetype, tree name, int protect)
1285 tree rval = lookup_member (xbasetype, name, protect, /*want_type=*/false,
1286 tf_warning_or_error);
1288 /* Ignore non-functions, but propagate the ambiguity list. */
1289 if (!error_operand_p (rval)
1290 && (rval && !BASELINK_P (rval)))
1296 /* Return the index in the CLASSTYPE_METHOD_VEC for CLASS_TYPE
1297 corresponding to "operator TYPE ()", or -1 if there is no such
1298 operator. Only CLASS_TYPE itself is searched; this routine does
1299 not scan the base classes of CLASS_TYPE. */
1302 lookup_conversion_operator (tree class_type, tree type)
1306 if (TYPE_HAS_CONVERSION (class_type))
1310 VEC(tree,gc) *methods = CLASSTYPE_METHOD_VEC (class_type);
1312 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
1313 VEC_iterate (tree, methods, i, fn); ++i)
1315 /* All the conversion operators come near the beginning of
1316 the class. Therefore, if FN is not a conversion
1317 operator, there is no matching conversion operator in
1319 fn = OVL_CURRENT (fn);
1320 if (!DECL_CONV_FN_P (fn))
1323 if (TREE_CODE (fn) == TEMPLATE_DECL)
1324 /* All the templated conversion functions are on the same
1325 slot, so remember it. */
1327 else if (same_type_p (DECL_CONV_FN_TYPE (fn), type))
1335 /* TYPE is a class type. Return the index of the fields within
1336 the method vector with name NAME, or -1 if no such field exists.
1337 Does not lazily declare implicitly-declared member functions. */
1340 lookup_fnfields_idx_nolazy (tree type, tree name)
1342 VEC(tree,gc) *method_vec;
1347 if (!CLASS_TYPE_P (type))
1350 method_vec = CLASSTYPE_METHOD_VEC (type);
1354 #ifdef GATHER_STATISTICS
1355 n_calls_lookup_fnfields_1++;
1356 #endif /* GATHER_STATISTICS */
1358 /* Constructors are first... */
1359 if (name == ctor_identifier)
1361 fn = CLASSTYPE_CONSTRUCTORS (type);
1362 return fn ? CLASSTYPE_CONSTRUCTOR_SLOT : -1;
1364 /* and destructors are second. */
1365 if (name == dtor_identifier)
1367 fn = CLASSTYPE_DESTRUCTORS (type);
1368 return fn ? CLASSTYPE_DESTRUCTOR_SLOT : -1;
1370 if (IDENTIFIER_TYPENAME_P (name))
1371 return lookup_conversion_operator (type, TREE_TYPE (name));
1373 /* Skip the conversion operators. */
1374 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
1375 VEC_iterate (tree, method_vec, i, fn);
1377 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1380 /* If the type is complete, use binary search. */
1381 if (COMPLETE_TYPE_P (type))
1387 hi = VEC_length (tree, method_vec);
1392 #ifdef GATHER_STATISTICS
1393 n_outer_fields_searched++;
1394 #endif /* GATHER_STATISTICS */
1396 tmp = VEC_index (tree, method_vec, i);
1397 tmp = DECL_NAME (OVL_CURRENT (tmp));
1400 else if (tmp < name)
1407 for (; VEC_iterate (tree, method_vec, i, fn); ++i)
1409 #ifdef GATHER_STATISTICS
1410 n_outer_fields_searched++;
1411 #endif /* GATHER_STATISTICS */
1412 if (DECL_NAME (OVL_CURRENT (fn)) == name)
1419 /* TYPE is a class type. Return the index of the fields within
1420 the method vector with name NAME, or -1 if no such field exists. */
1423 lookup_fnfields_1 (tree type, tree name)
1425 if (!CLASS_TYPE_P (type))
1428 if (COMPLETE_TYPE_P (type))
1430 if ((name == ctor_identifier
1431 || name == base_ctor_identifier
1432 || name == complete_ctor_identifier))
1434 if (CLASSTYPE_LAZY_DEFAULT_CTOR (type))
1435 lazily_declare_fn (sfk_constructor, type);
1436 if (CLASSTYPE_LAZY_COPY_CTOR (type))
1437 lazily_declare_fn (sfk_copy_constructor, type);
1438 if (CLASSTYPE_LAZY_MOVE_CTOR (type))
1439 lazily_declare_fn (sfk_move_constructor, type);
1441 else if (name == ansi_assopname (NOP_EXPR))
1443 if (CLASSTYPE_LAZY_COPY_ASSIGN (type))
1444 lazily_declare_fn (sfk_copy_assignment, type);
1445 if (CLASSTYPE_LAZY_MOVE_ASSIGN (type))
1446 lazily_declare_fn (sfk_move_assignment, type);
1448 else if ((name == dtor_identifier
1449 || name == base_dtor_identifier
1450 || name == complete_dtor_identifier
1451 || name == deleting_dtor_identifier)
1452 && CLASSTYPE_LAZY_DESTRUCTOR (type))
1453 lazily_declare_fn (sfk_destructor, type);
1456 return lookup_fnfields_idx_nolazy (type, name);
1459 /* TYPE is a class type. Return the field within the method vector with
1460 name NAME, or NULL_TREE if no such field exists. */
1463 lookup_fnfields_slot (tree type, tree name)
1465 int ix = lookup_fnfields_1 (complete_type (type), name);
1468 return VEC_index (tree, CLASSTYPE_METHOD_VEC (type), ix);
1471 /* As above, but avoid lazily declaring functions. */
1474 lookup_fnfields_slot_nolazy (tree type, tree name)
1476 int ix = lookup_fnfields_idx_nolazy (complete_type (type), name);
1479 return VEC_index (tree, CLASSTYPE_METHOD_VEC (type), ix);
1482 /* Like lookup_fnfields_1, except that the name is extracted from
1483 FUNCTION, which is a FUNCTION_DECL or a TEMPLATE_DECL. */
1486 class_method_index_for_fn (tree class_type, tree function)
1488 gcc_assert (TREE_CODE (function) == FUNCTION_DECL
1489 || DECL_FUNCTION_TEMPLATE_P (function));
1491 return lookup_fnfields_1 (class_type,
1492 DECL_CONSTRUCTOR_P (function) ? ctor_identifier :
1493 DECL_DESTRUCTOR_P (function) ? dtor_identifier :
1494 DECL_NAME (function));
1498 /* DECL is the result of a qualified name lookup. QUALIFYING_SCOPE is
1499 the class or namespace used to qualify the name. CONTEXT_CLASS is
1500 the class corresponding to the object in which DECL will be used.
1501 Return a possibly modified version of DECL that takes into account
1504 In particular, consider an expression like `B::m' in the context of
1505 a derived class `D'. If `B::m' has been resolved to a BASELINK,
1506 then the most derived class indicated by the BASELINK_BINFO will be
1507 `B', not `D'. This function makes that adjustment. */
1510 adjust_result_of_qualified_name_lookup (tree decl,
1511 tree qualifying_scope,
1514 if (context_class && context_class != error_mark_node
1515 && CLASS_TYPE_P (context_class)
1516 && CLASS_TYPE_P (qualifying_scope)
1517 && DERIVED_FROM_P (qualifying_scope, context_class)
1518 && BASELINK_P (decl))
1522 /* Look for the QUALIFYING_SCOPE as a base of the CONTEXT_CLASS.
1523 Because we do not yet know which function will be chosen by
1524 overload resolution, we cannot yet check either accessibility
1525 or ambiguity -- in either case, the choice of a static member
1526 function might make the usage valid. */
1527 base = lookup_base (context_class, qualifying_scope,
1528 ba_unique | ba_quiet, NULL);
1531 BASELINK_ACCESS_BINFO (decl) = base;
1532 BASELINK_BINFO (decl)
1533 = lookup_base (base, BINFO_TYPE (BASELINK_BINFO (decl)),
1534 ba_unique | ba_quiet,
1543 /* Walk the class hierarchy within BINFO, in a depth-first traversal.
1544 PRE_FN is called in preorder, while POST_FN is called in postorder.
1545 If PRE_FN returns DFS_SKIP_BASES, child binfos will not be
1546 walked. If PRE_FN or POST_FN returns a different non-NULL value,
1547 that value is immediately returned and the walk is terminated. One
1548 of PRE_FN and POST_FN can be NULL. At each node, PRE_FN and
1549 POST_FN are passed the binfo to examine and the caller's DATA
1550 value. All paths are walked, thus virtual and morally virtual
1551 binfos can be multiply walked. */
1554 dfs_walk_all (tree binfo, tree (*pre_fn) (tree, void *),
1555 tree (*post_fn) (tree, void *), void *data)
1561 /* Call the pre-order walking function. */
1564 rval = pre_fn (binfo, data);
1567 if (rval == dfs_skip_bases)
1573 /* Find the next child binfo to walk. */
1574 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1576 rval = dfs_walk_all (base_binfo, pre_fn, post_fn, data);
1582 /* Call the post-order walking function. */
1585 rval = post_fn (binfo, data);
1586 gcc_assert (rval != dfs_skip_bases);
1593 /* Worker for dfs_walk_once. This behaves as dfs_walk_all, except
1594 that binfos are walked at most once. */
1597 dfs_walk_once_r (tree binfo, tree (*pre_fn) (tree, void *),
1598 tree (*post_fn) (tree, void *), void *data)
1604 /* Call the pre-order walking function. */
1607 rval = pre_fn (binfo, data);
1610 if (rval == dfs_skip_bases)
1617 /* Find the next child binfo to walk. */
1618 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1620 if (BINFO_VIRTUAL_P (base_binfo))
1622 if (BINFO_MARKED (base_binfo))
1624 BINFO_MARKED (base_binfo) = 1;
1627 rval = dfs_walk_once_r (base_binfo, pre_fn, post_fn, data);
1633 /* Call the post-order walking function. */
1636 rval = post_fn (binfo, data);
1637 gcc_assert (rval != dfs_skip_bases);
1644 /* Worker for dfs_walk_once. Recursively unmark the virtual base binfos of
1648 dfs_unmark_r (tree binfo)
1653 /* Process the basetypes. */
1654 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1656 if (BINFO_VIRTUAL_P (base_binfo))
1658 if (!BINFO_MARKED (base_binfo))
1660 BINFO_MARKED (base_binfo) = 0;
1662 /* Only walk, if it can contain more virtual bases. */
1663 if (CLASSTYPE_VBASECLASSES (BINFO_TYPE (base_binfo)))
1664 dfs_unmark_r (base_binfo);
1668 /* Like dfs_walk_all, except that binfos are not multiply walked. For
1669 non-diamond shaped hierarchies this is the same as dfs_walk_all.
1670 For diamond shaped hierarchies we must mark the virtual bases, to
1671 avoid multiple walks. */
1674 dfs_walk_once (tree binfo, tree (*pre_fn) (tree, void *),
1675 tree (*post_fn) (tree, void *), void *data)
1677 static int active = 0; /* We must not be called recursively. */
1680 gcc_assert (pre_fn || post_fn);
1681 gcc_assert (!active);
1684 if (!CLASSTYPE_DIAMOND_SHAPED_P (BINFO_TYPE (binfo)))
1685 /* We are not diamond shaped, and therefore cannot encounter the
1686 same binfo twice. */
1687 rval = dfs_walk_all (binfo, pre_fn, post_fn, data);
1690 rval = dfs_walk_once_r (binfo, pre_fn, post_fn, data);
1691 if (!BINFO_INHERITANCE_CHAIN (binfo))
1693 /* We are at the top of the hierarchy, and can use the
1694 CLASSTYPE_VBASECLASSES list for unmarking the virtual
1696 VEC(tree,gc) *vbases;
1700 for (vbases = CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)), ix = 0;
1701 VEC_iterate (tree, vbases, ix, base_binfo); ix++)
1702 BINFO_MARKED (base_binfo) = 0;
1705 dfs_unmark_r (binfo);
1713 /* Worker function for dfs_walk_once_accessible. Behaves like
1714 dfs_walk_once_r, except (a) FRIENDS_P is true if special
1715 access given by the current context should be considered, (b) ONCE
1716 indicates whether bases should be marked during traversal. */
1719 dfs_walk_once_accessible_r (tree binfo, bool friends_p, bool once,
1720 tree (*pre_fn) (tree, void *),
1721 tree (*post_fn) (tree, void *), void *data)
1723 tree rval = NULL_TREE;
1727 /* Call the pre-order walking function. */
1730 rval = pre_fn (binfo, data);
1733 if (rval == dfs_skip_bases)
1740 /* Find the next child binfo to walk. */
1741 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1743 bool mark = once && BINFO_VIRTUAL_P (base_binfo);
1745 if (mark && BINFO_MARKED (base_binfo))
1748 /* If the base is inherited via private or protected
1749 inheritance, then we can't see it, unless we are a friend of
1750 the current binfo. */
1751 if (BINFO_BASE_ACCESS (binfo, ix) != access_public_node)
1756 scope = current_scope ();
1758 || TREE_CODE (scope) == NAMESPACE_DECL
1759 || !is_friend (BINFO_TYPE (binfo), scope))
1764 BINFO_MARKED (base_binfo) = 1;
1766 rval = dfs_walk_once_accessible_r (base_binfo, friends_p, once,
1767 pre_fn, post_fn, data);
1773 /* Call the post-order walking function. */
1776 rval = post_fn (binfo, data);
1777 gcc_assert (rval != dfs_skip_bases);
1784 /* Like dfs_walk_once except that only accessible bases are walked.
1785 FRIENDS_P indicates whether friendship of the local context
1786 should be considered when determining accessibility. */
1789 dfs_walk_once_accessible (tree binfo, bool friends_p,
1790 tree (*pre_fn) (tree, void *),
1791 tree (*post_fn) (tree, void *), void *data)
1793 bool diamond_shaped = CLASSTYPE_DIAMOND_SHAPED_P (BINFO_TYPE (binfo));
1794 tree rval = dfs_walk_once_accessible_r (binfo, friends_p, diamond_shaped,
1795 pre_fn, post_fn, data);
1799 if (!BINFO_INHERITANCE_CHAIN (binfo))
1801 /* We are at the top of the hierarchy, and can use the
1802 CLASSTYPE_VBASECLASSES list for unmarking the virtual
1804 VEC(tree,gc) *vbases;
1808 for (vbases = CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)), ix = 0;
1809 VEC_iterate (tree, vbases, ix, base_binfo); ix++)
1810 BINFO_MARKED (base_binfo) = 0;
1813 dfs_unmark_r (binfo);
1818 /* Check that virtual overrider OVERRIDER is acceptable for base function
1819 BASEFN. Issue diagnostic, and return zero, if unacceptable. */
1822 check_final_overrider (tree overrider, tree basefn)
1824 tree over_type = TREE_TYPE (overrider);
1825 tree base_type = TREE_TYPE (basefn);
1826 tree over_return = TREE_TYPE (over_type);
1827 tree base_return = TREE_TYPE (base_type);
1828 tree over_throw, base_throw;
1832 if (DECL_INVALID_OVERRIDER_P (overrider))
1835 if (same_type_p (base_return, over_return))
1837 else if ((CLASS_TYPE_P (over_return) && CLASS_TYPE_P (base_return))
1838 || (TREE_CODE (base_return) == TREE_CODE (over_return)
1839 && POINTER_TYPE_P (base_return)))
1841 /* Potentially covariant. */
1842 unsigned base_quals, over_quals;
1844 fail = !POINTER_TYPE_P (base_return);
1847 fail = cp_type_quals (base_return) != cp_type_quals (over_return);
1849 base_return = TREE_TYPE (base_return);
1850 over_return = TREE_TYPE (over_return);
1852 base_quals = cp_type_quals (base_return);
1853 over_quals = cp_type_quals (over_return);
1855 if ((base_quals & over_quals) != over_quals)
1858 if (CLASS_TYPE_P (base_return) && CLASS_TYPE_P (over_return))
1860 /* Strictly speaking, the standard requires the return type to be
1861 complete even if it only differs in cv-quals, but that seems
1862 like a bug in the wording. */
1863 if (!same_type_ignoring_top_level_qualifiers_p (base_return, over_return))
1865 tree binfo = lookup_base (over_return, base_return,
1866 ba_check | ba_quiet, NULL);
1873 && can_convert (TREE_TYPE (base_type), TREE_TYPE (over_type)))
1874 /* GNU extension, allow trivial pointer conversions such as
1875 converting to void *, or qualification conversion. */
1877 /* can_convert will permit user defined conversion from a
1878 (reference to) class type. We must reject them. */
1879 over_return = non_reference (TREE_TYPE (over_type));
1880 if (CLASS_TYPE_P (over_return))
1884 warning (0, "deprecated covariant return type for %q+#D",
1886 warning (0, " overriding %q+#D", basefn);
1900 error ("invalid covariant return type for %q+#D", overrider);
1901 error (" overriding %q+#D", basefn);
1905 error ("conflicting return type specified for %q+#D", overrider);
1906 error (" overriding %q+#D", basefn);
1908 DECL_INVALID_OVERRIDER_P (overrider) = 1;
1912 /* Check throw specifier is at least as strict. */
1913 maybe_instantiate_noexcept (basefn);
1914 maybe_instantiate_noexcept (overrider);
1915 base_throw = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (basefn));
1916 over_throw = TYPE_RAISES_EXCEPTIONS (TREE_TYPE (overrider));
1918 if (!comp_except_specs (base_throw, over_throw, ce_derived))
1920 error ("looser throw specifier for %q+#F", overrider);
1921 error (" overriding %q+#F", basefn);
1922 DECL_INVALID_OVERRIDER_P (overrider) = 1;
1926 /* Check for conflicting type attributes. */
1927 if (!comp_type_attributes (over_type, base_type))
1929 error ("conflicting type attributes specified for %q+#D", overrider);
1930 error (" overriding %q+#D", basefn);
1931 DECL_INVALID_OVERRIDER_P (overrider) = 1;
1935 if (DECL_DELETED_FN (basefn) != DECL_DELETED_FN (overrider))
1937 if (DECL_DELETED_FN (overrider))
1939 error ("deleted function %q+D", overrider);
1940 error ("overriding non-deleted function %q+D", basefn);
1941 maybe_explain_implicit_delete (overrider);
1945 error ("non-deleted function %q+D", overrider);
1946 error ("overriding deleted function %q+D", basefn);
1950 if (DECL_FINAL_P (basefn))
1952 error ("virtual function %q+D", overrider);
1953 error ("overriding final function %q+D", basefn);
1959 /* Given a class TYPE, and a function decl FNDECL, look for
1960 virtual functions in TYPE's hierarchy which FNDECL overrides.
1961 We do not look in TYPE itself, only its bases.
1963 Returns nonzero, if we find any. Set FNDECL's DECL_VIRTUAL_P, if we
1964 find that it overrides anything.
1966 We check that every function which is overridden, is correctly
1970 look_for_overrides (tree type, tree fndecl)
1972 tree binfo = TYPE_BINFO (type);
1977 /* A constructor for a class T does not override a function T
1979 if (DECL_CONSTRUCTOR_P (fndecl))
1982 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1984 tree basetype = BINFO_TYPE (base_binfo);
1986 if (TYPE_POLYMORPHIC_P (basetype))
1987 found += look_for_overrides_r (basetype, fndecl);
1992 /* Look in TYPE for virtual functions with the same signature as
1996 look_for_overrides_here (tree type, tree fndecl)
2000 /* If there are no methods in TYPE (meaning that only implicitly
2001 declared methods will ever be provided for TYPE), then there are
2002 no virtual functions. */
2003 if (!CLASSTYPE_METHOD_VEC (type))
2006 if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fndecl))
2007 ix = CLASSTYPE_DESTRUCTOR_SLOT;
2009 ix = lookup_fnfields_1 (type, DECL_NAME (fndecl));
2012 tree fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (type), ix);
2014 for (; fns; fns = OVL_NEXT (fns))
2016 tree fn = OVL_CURRENT (fns);
2018 if (!DECL_VIRTUAL_P (fn))
2019 /* Not a virtual. */;
2020 else if (DECL_CONTEXT (fn) != type)
2021 /* Introduced with a using declaration. */;
2022 else if (DECL_STATIC_FUNCTION_P (fndecl))
2024 tree btypes = TYPE_ARG_TYPES (TREE_TYPE (fn));
2025 tree dtypes = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
2026 if (compparms (TREE_CHAIN (btypes), dtypes))
2029 else if (same_signature_p (fndecl, fn))
2036 /* Look in TYPE for virtual functions overridden by FNDECL. Check both
2037 TYPE itself and its bases. */
2040 look_for_overrides_r (tree type, tree fndecl)
2042 tree fn = look_for_overrides_here (type, fndecl);
2045 if (DECL_STATIC_FUNCTION_P (fndecl))
2047 /* A static member function cannot match an inherited
2048 virtual member function. */
2049 error ("%q+#D cannot be declared", fndecl);
2050 error (" since %q+#D declared in base class", fn);
2054 /* It's definitely virtual, even if not explicitly set. */
2055 DECL_VIRTUAL_P (fndecl) = 1;
2056 check_final_overrider (fndecl, fn);
2061 /* We failed to find one declared in this class. Look in its bases. */
2062 return look_for_overrides (type, fndecl);
2065 /* Called via dfs_walk from dfs_get_pure_virtuals. */
2068 dfs_get_pure_virtuals (tree binfo, void *data)
2070 tree type = (tree) data;
2072 /* We're not interested in primary base classes; the derived class
2073 of which they are a primary base will contain the information we
2075 if (!BINFO_PRIMARY_P (binfo))
2079 for (virtuals = BINFO_VIRTUALS (binfo);
2081 virtuals = TREE_CHAIN (virtuals))
2082 if (DECL_PURE_VIRTUAL_P (BV_FN (virtuals)))
2083 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (type),
2090 /* Set CLASSTYPE_PURE_VIRTUALS for TYPE. */
2093 get_pure_virtuals (tree type)
2095 /* Clear the CLASSTYPE_PURE_VIRTUALS list; whatever is already there
2096 is going to be overridden. */
2097 CLASSTYPE_PURE_VIRTUALS (type) = NULL;
2098 /* Now, run through all the bases which are not primary bases, and
2099 collect the pure virtual functions. We look at the vtable in
2100 each class to determine what pure virtual functions are present.
2101 (A primary base is not interesting because the derived class of
2102 which it is a primary base will contain vtable entries for the
2103 pure virtuals in the base class. */
2104 dfs_walk_once (TYPE_BINFO (type), NULL, dfs_get_pure_virtuals, type);
2107 /* Debug info for C++ classes can get very large; try to avoid
2108 emitting it everywhere.
2110 Note that this optimization wins even when the target supports
2111 BINCL (if only slightly), and reduces the amount of work for the
2115 maybe_suppress_debug_info (tree t)
2117 if (write_symbols == NO_DEBUG)
2120 /* We might have set this earlier in cp_finish_decl. */
2121 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 0;
2123 /* Always emit the information for each class every time. */
2124 if (flag_emit_class_debug_always)
2127 /* If we already know how we're handling this class, handle debug info
2129 if (CLASSTYPE_INTERFACE_KNOWN (t))
2131 if (CLASSTYPE_INTERFACE_ONLY (t))
2132 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 1;
2133 /* else don't set it. */
2135 /* If the class has a vtable, write out the debug info along with
2137 else if (TYPE_CONTAINS_VPTR_P (t))
2138 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 1;
2140 /* Otherwise, just emit the debug info normally. */
2143 /* Note that we want debugging information for a base class of a class
2144 whose vtable is being emitted. Normally, this would happen because
2145 calling the constructor for a derived class implies calling the
2146 constructors for all bases, which involve initializing the
2147 appropriate vptr with the vtable for the base class; but in the
2148 presence of optimization, this initialization may be optimized
2149 away, so we tell finish_vtable_vardecl that we want the debugging
2150 information anyway. */
2153 dfs_debug_mark (tree binfo, void *data ATTRIBUTE_UNUSED)
2155 tree t = BINFO_TYPE (binfo);
2157 if (CLASSTYPE_DEBUG_REQUESTED (t))
2158 return dfs_skip_bases;
2160 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
2165 /* Write out the debugging information for TYPE, whose vtable is being
2166 emitted. Also walk through our bases and note that we want to
2167 write out information for them. This avoids the problem of not
2168 writing any debug info for intermediate basetypes whose
2169 constructors, and thus the references to their vtables, and thus
2170 the vtables themselves, were optimized away. */
2173 note_debug_info_needed (tree type)
2175 if (TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type)))
2177 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type)) = 0;
2178 rest_of_type_compilation (type, toplevel_bindings_p ());
2181 dfs_walk_all (TYPE_BINFO (type), dfs_debug_mark, NULL, 0);
2185 print_search_statistics (void)
2187 #ifdef GATHER_STATISTICS
2188 fprintf (stderr, "%d fields searched in %d[%d] calls to lookup_field[_1]\n",
2189 n_fields_searched, n_calls_lookup_field, n_calls_lookup_field_1);
2190 fprintf (stderr, "%d fnfields searched in %d calls to lookup_fnfields\n",
2191 n_outer_fields_searched, n_calls_lookup_fnfields);
2192 fprintf (stderr, "%d calls to get_base_type\n", n_calls_get_base_type);
2193 #else /* GATHER_STATISTICS */
2194 fprintf (stderr, "no search statistics\n");
2195 #endif /* GATHER_STATISTICS */
2199 reinit_search_statistics (void)
2201 #ifdef GATHER_STATISTICS
2202 n_fields_searched = 0;
2203 n_calls_lookup_field = 0, n_calls_lookup_field_1 = 0;
2204 n_calls_lookup_fnfields = 0, n_calls_lookup_fnfields_1 = 0;
2205 n_calls_get_base_type = 0;
2206 n_outer_fields_searched = 0;
2207 n_contexts_saved = 0;
2208 #endif /* GATHER_STATISTICS */
2211 /* Helper for lookup_conversions_r. TO_TYPE is the type converted to
2212 by a conversion op in base BINFO. VIRTUAL_DEPTH is nonzero if
2213 BINFO is morally virtual, and VIRTUALNESS is nonzero if virtual
2214 bases have been encountered already in the tree walk. PARENT_CONVS
2215 is the list of lists of conversion functions that could hide CONV
2216 and OTHER_CONVS is the list of lists of conversion functions that
2217 could hide or be hidden by CONV, should virtualness be involved in
2218 the hierarchy. Merely checking the conversion op's name is not
2219 enough because two conversion operators to the same type can have
2220 different names. Return nonzero if we are visible. */
2223 check_hidden_convs (tree binfo, int virtual_depth, int virtualness,
2224 tree to_type, tree parent_convs, tree other_convs)
2228 /* See if we are hidden by a parent conversion. */
2229 for (level = parent_convs; level; level = TREE_CHAIN (level))
2230 for (probe = TREE_VALUE (level); probe; probe = TREE_CHAIN (probe))
2231 if (same_type_p (to_type, TREE_TYPE (probe)))
2234 if (virtual_depth || virtualness)
2236 /* In a virtual hierarchy, we could be hidden, or could hide a
2237 conversion function on the other_convs list. */
2238 for (level = other_convs; level; level = TREE_CHAIN (level))
2244 if (!(virtual_depth || TREE_STATIC (level)))
2245 /* Neither is morally virtual, so cannot hide each other. */
2248 if (!TREE_VALUE (level))
2249 /* They evaporated away already. */
2252 they_hide_us = (virtual_depth
2253 && original_binfo (binfo, TREE_PURPOSE (level)));
2254 we_hide_them = (!they_hide_us && TREE_STATIC (level)
2255 && original_binfo (TREE_PURPOSE (level), binfo));
2257 if (!(we_hide_them || they_hide_us))
2258 /* Neither is within the other, so no hiding can occur. */
2261 for (prev = &TREE_VALUE (level), other = *prev; other;)
2263 if (same_type_p (to_type, TREE_TYPE (other)))
2266 /* We are hidden. */
2271 /* We hide the other one. */
2272 other = TREE_CHAIN (other);
2277 prev = &TREE_CHAIN (other);
2285 /* Helper for lookup_conversions_r. PARENT_CONVS is a list of lists
2286 of conversion functions, the first slot will be for the current
2287 binfo, if MY_CONVS is non-NULL. CHILD_CONVS is the list of lists
2288 of conversion functions from children of the current binfo,
2289 concatenated with conversions from elsewhere in the hierarchy --
2290 that list begins with OTHER_CONVS. Return a single list of lists
2291 containing only conversions from the current binfo and its
2295 split_conversions (tree my_convs, tree parent_convs,
2296 tree child_convs, tree other_convs)
2301 /* Remove the original other_convs portion from child_convs. */
2302 for (prev = NULL, t = child_convs;
2303 t != other_convs; prev = t, t = TREE_CHAIN (t))
2307 TREE_CHAIN (prev) = NULL_TREE;
2309 child_convs = NULL_TREE;
2311 /* Attach the child convs to any we had at this level. */
2314 my_convs = parent_convs;
2315 TREE_CHAIN (my_convs) = child_convs;
2318 my_convs = child_convs;
2323 /* Worker for lookup_conversions. Lookup conversion functions in
2324 BINFO and its children. VIRTUAL_DEPTH is nonzero, if BINFO is in
2325 a morally virtual base, and VIRTUALNESS is nonzero, if we've
2326 encountered virtual bases already in the tree walk. PARENT_CONVS &
2327 PARENT_TPL_CONVS are lists of list of conversions within parent
2328 binfos. OTHER_CONVS and OTHER_TPL_CONVS are conversions found
2329 elsewhere in the tree. Return the conversions found within this
2330 portion of the graph in CONVS and TPL_CONVS. Return nonzero is we
2331 encountered virtualness. We keep template and non-template
2332 conversions separate, to avoid unnecessary type comparisons.
2334 The located conversion functions are held in lists of lists. The
2335 TREE_VALUE of the outer list is the list of conversion functions
2336 found in a particular binfo. The TREE_PURPOSE of both the outer
2337 and inner lists is the binfo at which those conversions were
2338 found. TREE_STATIC is set for those lists within of morally
2339 virtual binfos. The TREE_VALUE of the inner list is the conversion
2340 function or overload itself. The TREE_TYPE of each inner list node
2341 is the converted-to type. */
2344 lookup_conversions_r (tree binfo,
2345 int virtual_depth, int virtualness,
2346 tree parent_convs, tree parent_tpl_convs,
2347 tree other_convs, tree other_tpl_convs,
2348 tree *convs, tree *tpl_convs)
2350 int my_virtualness = 0;
2351 tree my_convs = NULL_TREE;
2352 tree my_tpl_convs = NULL_TREE;
2353 tree child_convs = NULL_TREE;
2354 tree child_tpl_convs = NULL_TREE;
2357 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (BINFO_TYPE (binfo));
2360 /* If we have no conversion operators, then don't look. */
2361 if (!TYPE_HAS_CONVERSION (BINFO_TYPE (binfo)))
2363 *convs = *tpl_convs = NULL_TREE;
2368 if (BINFO_VIRTUAL_P (binfo))
2371 /* First, locate the unhidden ones at this level. */
2372 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2373 VEC_iterate (tree, method_vec, i, conv);
2376 tree cur = OVL_CURRENT (conv);
2378 if (!DECL_CONV_FN_P (cur))
2381 if (TREE_CODE (cur) == TEMPLATE_DECL)
2383 /* Only template conversions can be overloaded, and we must
2384 flatten them out and check each one individually. */
2387 for (tpls = conv; tpls; tpls = OVL_NEXT (tpls))
2389 tree tpl = OVL_CURRENT (tpls);
2390 tree type = DECL_CONV_FN_TYPE (tpl);
2392 if (check_hidden_convs (binfo, virtual_depth, virtualness,
2393 type, parent_tpl_convs, other_tpl_convs))
2395 my_tpl_convs = tree_cons (binfo, tpl, my_tpl_convs);
2396 TREE_TYPE (my_tpl_convs) = type;
2399 TREE_STATIC (my_tpl_convs) = 1;
2407 tree name = DECL_NAME (cur);
2409 if (!IDENTIFIER_MARKED (name))
2411 tree type = DECL_CONV_FN_TYPE (cur);
2413 if (check_hidden_convs (binfo, virtual_depth, virtualness,
2414 type, parent_convs, other_convs))
2416 my_convs = tree_cons (binfo, conv, my_convs);
2417 TREE_TYPE (my_convs) = type;
2420 TREE_STATIC (my_convs) = 1;
2423 IDENTIFIER_MARKED (name) = 1;
2431 parent_convs = tree_cons (binfo, my_convs, parent_convs);
2433 TREE_STATIC (parent_convs) = 1;
2438 parent_tpl_convs = tree_cons (binfo, my_tpl_convs, parent_tpl_convs);
2440 TREE_STATIC (parent_tpl_convs) = 1;
2443 child_convs = other_convs;
2444 child_tpl_convs = other_tpl_convs;
2446 /* Now iterate over each base, looking for more conversions. */
2447 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
2449 tree base_convs, base_tpl_convs;
2450 unsigned base_virtualness;
2452 base_virtualness = lookup_conversions_r (base_binfo,
2453 virtual_depth, virtualness,
2454 parent_convs, parent_tpl_convs,
2455 child_convs, child_tpl_convs,
2456 &base_convs, &base_tpl_convs);
2457 if (base_virtualness)
2458 my_virtualness = virtualness = 1;
2459 child_convs = chainon (base_convs, child_convs);
2460 child_tpl_convs = chainon (base_tpl_convs, child_tpl_convs);
2463 /* Unmark the conversions found at this level */
2464 for (conv = my_convs; conv; conv = TREE_CHAIN (conv))
2465 IDENTIFIER_MARKED (DECL_NAME (OVL_CURRENT (TREE_VALUE (conv)))) = 0;
2467 *convs = split_conversions (my_convs, parent_convs,
2468 child_convs, other_convs);
2469 *tpl_convs = split_conversions (my_tpl_convs, parent_tpl_convs,
2470 child_tpl_convs, other_tpl_convs);
2472 return my_virtualness;
2475 /* Return a TREE_LIST containing all the non-hidden user-defined
2476 conversion functions for TYPE (and its base-classes). The
2477 TREE_VALUE of each node is the FUNCTION_DECL of the conversion
2478 function. The TREE_PURPOSE is the BINFO from which the conversion
2479 functions in this node were selected. This function is effectively
2480 performing a set of member lookups as lookup_fnfield does, but
2481 using the type being converted to as the unique key, rather than the
2485 lookup_conversions (tree type)
2487 tree convs, tpl_convs;
2488 tree list = NULL_TREE;
2490 complete_type (type);
2491 if (!TYPE_BINFO (type))
2494 lookup_conversions_r (TYPE_BINFO (type), 0, 0,
2495 NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE,
2496 &convs, &tpl_convs);
2498 /* Flatten the list-of-lists */
2499 for (; convs; convs = TREE_CHAIN (convs))
2503 for (probe = TREE_VALUE (convs); probe; probe = next)
2505 next = TREE_CHAIN (probe);
2507 TREE_CHAIN (probe) = list;
2512 for (; tpl_convs; tpl_convs = TREE_CHAIN (tpl_convs))
2516 for (probe = TREE_VALUE (tpl_convs); probe; probe = next)
2518 next = TREE_CHAIN (probe);
2520 TREE_CHAIN (probe) = list;
2528 /* Returns the binfo of the first direct or indirect virtual base derived
2529 from BINFO, or NULL if binfo is not via virtual. */
2532 binfo_from_vbase (tree binfo)
2534 for (; binfo; binfo = BINFO_INHERITANCE_CHAIN (binfo))
2536 if (BINFO_VIRTUAL_P (binfo))
2542 /* Returns the binfo of the first direct or indirect virtual base derived
2543 from BINFO up to the TREE_TYPE, LIMIT, or NULL if binfo is not
2547 binfo_via_virtual (tree binfo, tree limit)
2549 if (limit && !CLASSTYPE_VBASECLASSES (limit))
2550 /* LIMIT has no virtual bases, so BINFO cannot be via one. */
2553 for (; binfo && !SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), limit);
2554 binfo = BINFO_INHERITANCE_CHAIN (binfo))
2556 if (BINFO_VIRTUAL_P (binfo))
2562 /* BINFO is a base binfo in the complete type BINFO_TYPE (HERE).
2563 Find the equivalent binfo within whatever graph HERE is located.
2564 This is the inverse of original_binfo. */
2567 copied_binfo (tree binfo, tree here)
2569 tree result = NULL_TREE;
2571 if (BINFO_VIRTUAL_P (binfo))
2575 for (t = here; BINFO_INHERITANCE_CHAIN (t);
2576 t = BINFO_INHERITANCE_CHAIN (t))
2579 result = binfo_for_vbase (BINFO_TYPE (binfo), BINFO_TYPE (t));
2581 else if (BINFO_INHERITANCE_CHAIN (binfo))
2587 cbinfo = copied_binfo (BINFO_INHERITANCE_CHAIN (binfo), here);
2588 for (ix = 0; BINFO_BASE_ITERATE (cbinfo, ix, base_binfo); ix++)
2589 if (SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo), BINFO_TYPE (binfo)))
2591 result = base_binfo;
2597 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (here), BINFO_TYPE (binfo)));
2601 gcc_assert (result);
2606 binfo_for_vbase (tree base, tree t)
2610 VEC(tree,gc) *vbases;
2612 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
2613 VEC_iterate (tree, vbases, ix, binfo); ix++)
2614 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), base))
2619 /* BINFO is some base binfo of HERE, within some other
2620 hierarchy. Return the equivalent binfo, but in the hierarchy
2621 dominated by HERE. This is the inverse of copied_binfo. If BINFO
2622 is not a base binfo of HERE, returns NULL_TREE. */
2625 original_binfo (tree binfo, tree here)
2629 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (here)))
2631 else if (BINFO_VIRTUAL_P (binfo))
2632 result = (CLASSTYPE_VBASECLASSES (BINFO_TYPE (here))
2633 ? binfo_for_vbase (BINFO_TYPE (binfo), BINFO_TYPE (here))
2635 else if (BINFO_INHERITANCE_CHAIN (binfo))
2639 base_binfos = original_binfo (BINFO_INHERITANCE_CHAIN (binfo), here);
2645 for (ix = 0; (base_binfo = BINFO_BASE_BINFO (base_binfos, ix)); ix++)
2646 if (SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
2647 BINFO_TYPE (binfo)))
2649 result = base_binfo;