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
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"
40 static int is_subobject_of_p (tree, tree);
41 static tree dfs_lookup_base (tree, void *);
42 static tree dfs_dcast_hint_pre (tree, void *);
43 static tree dfs_dcast_hint_post (tree, void *);
44 static tree dfs_debug_mark (tree, void *);
45 static tree dfs_walk_once_r (tree, tree (*pre_fn) (tree, void *),
46 tree (*post_fn) (tree, void *), void *data);
47 static void dfs_unmark_r (tree);
48 static int check_hidden_convs (tree, int, int, tree, tree, tree);
49 static tree split_conversions (tree, tree, tree, tree);
50 static int lookup_conversions_r (tree, int, int,
51 tree, tree, tree, tree, tree *, tree *);
52 static int look_for_overrides_r (tree, tree);
53 static tree lookup_field_r (tree, void *);
54 static tree dfs_accessible_post (tree, void *);
55 static tree dfs_walk_once_accessible_r (tree, bool, bool,
56 tree (*pre_fn) (tree, void *),
57 tree (*post_fn) (tree, void *),
59 static tree dfs_walk_once_accessible (tree, bool,
60 tree (*pre_fn) (tree, void *),
61 tree (*post_fn) (tree, void *),
63 static tree dfs_access_in_type (tree, void *);
64 static access_kind access_in_type (tree, tree);
65 static int protected_accessible_p (tree, tree, tree);
66 static int friend_accessible_p (tree, tree, tree);
67 static tree dfs_get_pure_virtuals (tree, void *);
70 /* Variables for gathering statistics. */
71 #ifdef GATHER_STATISTICS
72 static int n_fields_searched;
73 static int n_calls_lookup_field, n_calls_lookup_field_1;
74 static int n_calls_lookup_fnfields, n_calls_lookup_fnfields_1;
75 static int n_calls_get_base_type;
76 static int n_outer_fields_searched;
77 static int n_contexts_saved;
78 #endif /* GATHER_STATISTICS */
81 /* Data for lookup_base and its workers. */
83 struct lookup_base_data_s
85 tree t; /* type being searched. */
86 tree base; /* The base type we're looking for. */
87 tree binfo; /* Found binfo. */
88 bool via_virtual; /* Found via a virtual path. */
89 bool ambiguous; /* Found multiply ambiguous */
90 bool repeated_base; /* Whether there are repeated bases in the
92 bool want_any; /* Whether we want any matching binfo. */
95 /* Worker function for lookup_base. See if we've found the desired
96 base and update DATA_ (a pointer to LOOKUP_BASE_DATA_S). */
99 dfs_lookup_base (tree binfo, void *data_)
101 struct lookup_base_data_s *data = (struct lookup_base_data_s *) data_;
103 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->base))
109 = binfo_via_virtual (data->binfo, data->t) != NULL_TREE;
111 if (!data->repeated_base)
112 /* If there are no repeated bases, we can stop now. */
115 if (data->want_any && !data->via_virtual)
116 /* If this is a non-virtual base, then we can't do
120 return dfs_skip_bases;
124 gcc_assert (binfo != data->binfo);
126 /* We've found more than one matching binfo. */
129 /* This is immediately ambiguous. */
130 data->binfo = NULL_TREE;
131 data->ambiguous = true;
132 return error_mark_node;
135 /* Prefer one via a non-virtual path. */
136 if (!binfo_via_virtual (binfo, data->t))
139 data->via_virtual = false;
143 /* There must be repeated bases, otherwise we'd have stopped
144 on the first base we found. */
145 return dfs_skip_bases;
152 /* Returns true if type BASE is accessible in T. (BASE is known to be
153 a (possibly non-proper) base class of T.) If CONSIDER_LOCAL_P is
154 true, consider any special access of the current scope, or access
155 bestowed by friendship. */
158 accessible_base_p (tree t, tree base, bool consider_local_p)
162 /* [class.access.base]
164 A base class is said to be accessible if an invented public
165 member of the base class is accessible.
167 If BASE is a non-proper base, this condition is trivially
169 if (same_type_p (t, base))
171 /* Rather than inventing a public member, we use the implicit
172 public typedef created in the scope of every class. */
173 decl = TYPE_FIELDS (base);
174 while (!DECL_SELF_REFERENCE_P (decl))
175 decl = TREE_CHAIN (decl);
176 while (ANON_AGGR_TYPE_P (t))
177 t = TYPE_CONTEXT (t);
178 return accessible_p (t, decl, consider_local_p);
181 /* Lookup BASE in the hierarchy dominated by T. Do access checking as
182 ACCESS specifies. Return the binfo we discover. If KIND_PTR is
183 non-NULL, fill with information about what kind of base we
186 If the base is inaccessible, or ambiguous, and the ba_quiet bit is
187 not set in ACCESS, then an error is issued and error_mark_node is
188 returned. If the ba_quiet bit is set, then no error is issued and
189 NULL_TREE is returned. */
192 lookup_base (tree t, tree base, base_access access, base_kind *kind_ptr)
198 if (t == error_mark_node || base == error_mark_node)
201 *kind_ptr = bk_not_base;
202 return error_mark_node;
204 gcc_assert (TYPE_P (base));
213 t = complete_type (TYPE_MAIN_VARIANT (t));
214 t_binfo = TYPE_BINFO (t);
217 base = TYPE_MAIN_VARIANT (base);
219 /* If BASE is incomplete, it can't be a base of T--and instantiating it
220 might cause an error. */
221 if (t_binfo && CLASS_TYPE_P (base)
222 && (COMPLETE_TYPE_P (base) || TYPE_BEING_DEFINED (base)))
224 struct lookup_base_data_s data;
228 data.binfo = NULL_TREE;
229 data.ambiguous = data.via_virtual = false;
230 data.repeated_base = CLASSTYPE_REPEATED_BASE_P (t);
231 data.want_any = access == ba_any;
233 dfs_walk_once (t_binfo, dfs_lookup_base, NULL, &data);
237 bk = data.ambiguous ? bk_ambig : bk_not_base;
238 else if (binfo == t_binfo)
240 else if (data.via_virtual)
251 /* Check that the base is unambiguous and accessible. */
252 if (access != ba_any)
259 if (!(access & ba_quiet))
261 error ("%qT is an ambiguous base of %qT", base, t);
262 binfo = error_mark_node;
267 if ((access & ba_check_bit)
268 /* If BASE is incomplete, then BASE and TYPE are probably
269 the same, in which case BASE is accessible. If they
270 are not the same, then TYPE is invalid. In that case,
271 there's no need to issue another error here, and
272 there's no implicit typedef to use in the code that
273 follows, so we skip the check. */
274 && COMPLETE_TYPE_P (base)
275 && !accessible_base_p (t, base, !(access & ba_ignore_scope)))
277 if (!(access & ba_quiet))
279 error ("%qT is an inaccessible base of %qT", base, t);
280 binfo = error_mark_node;
284 bk = bk_inaccessible;
295 /* Data for dcast_base_hint walker. */
299 tree subtype; /* The base type we're looking for. */
300 int virt_depth; /* Number of virtual bases encountered from most
302 tree offset; /* Best hint offset discovered so far. */
303 bool repeated_base; /* Whether there are repeated bases in the
307 /* Worker for dcast_base_hint. Search for the base type being cast
311 dfs_dcast_hint_pre (tree binfo, void *data_)
313 struct dcast_data_s *data = (struct dcast_data_s *) data_;
315 if (BINFO_VIRTUAL_P (binfo))
318 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), data->subtype))
320 if (data->virt_depth)
322 data->offset = ssize_int (-1);
326 data->offset = ssize_int (-3);
328 data->offset = BINFO_OFFSET (binfo);
330 return data->repeated_base ? dfs_skip_bases : data->offset;
336 /* Worker for dcast_base_hint. Track the virtual depth. */
339 dfs_dcast_hint_post (tree binfo, void *data_)
341 struct dcast_data_s *data = (struct dcast_data_s *) data_;
343 if (BINFO_VIRTUAL_P (binfo))
349 /* The dynamic cast runtime needs a hint about how the static SUBTYPE type
350 started from is related to the required TARGET type, in order to optimize
351 the inheritance graph search. This information is independent of the
352 current context, and ignores private paths, hence get_base_distance is
353 inappropriate. Return a TREE specifying the base offset, BOFF.
354 BOFF >= 0, there is only one public non-virtual SUBTYPE base at offset BOFF,
355 and there are no public virtual SUBTYPE bases.
356 BOFF == -1, SUBTYPE occurs as multiple public virtual or non-virtual bases.
357 BOFF == -2, SUBTYPE is not a public base.
358 BOFF == -3, SUBTYPE occurs as multiple public non-virtual bases. */
361 dcast_base_hint (tree subtype, tree target)
363 struct dcast_data_s data;
365 data.subtype = subtype;
367 data.offset = NULL_TREE;
368 data.repeated_base = CLASSTYPE_REPEATED_BASE_P (target);
370 dfs_walk_once_accessible (TYPE_BINFO (target), /*friends=*/false,
371 dfs_dcast_hint_pre, dfs_dcast_hint_post, &data);
372 return data.offset ? data.offset : ssize_int (-2);
375 /* Search for a member with name NAME in a multiple inheritance
376 lattice specified by TYPE. If it does not exist, return NULL_TREE.
377 If the member is ambiguously referenced, return `error_mark_node'.
378 Otherwise, return a DECL with the indicated name. If WANT_TYPE is
379 true, type declarations are preferred. */
381 /* Do a 1-level search for NAME as a member of TYPE. The caller must
382 figure out whether it can access this field. (Since it is only one
383 level, this is reasonable.) */
386 lookup_field_1 (tree type, tree name, bool want_type)
390 if (TREE_CODE (type) == TEMPLATE_TYPE_PARM
391 || TREE_CODE (type) == BOUND_TEMPLATE_TEMPLATE_PARM
392 || TREE_CODE (type) == TYPENAME_TYPE)
393 /* The TYPE_FIELDS of a TEMPLATE_TYPE_PARM and
394 BOUND_TEMPLATE_TEMPLATE_PARM are not fields at all;
395 instead TYPE_FIELDS is the TEMPLATE_PARM_INDEX. (Miraculously,
396 the code often worked even when we treated the index as a list
398 The TYPE_FIELDS of TYPENAME_TYPE is its TYPENAME_TYPE_FULLNAME. */
401 if (CLASSTYPE_SORTED_FIELDS (type))
403 tree *fields = &CLASSTYPE_SORTED_FIELDS (type)->elts[0];
404 int lo = 0, hi = CLASSTYPE_SORTED_FIELDS (type)->len;
411 #ifdef GATHER_STATISTICS
413 #endif /* GATHER_STATISTICS */
415 if (DECL_NAME (fields[i]) > name)
417 else if (DECL_NAME (fields[i]) < name)
423 /* We might have a nested class and a field with the
424 same name; we sorted them appropriately via
425 field_decl_cmp, so just look for the first or last
426 field with this name. */
431 while (i >= lo && DECL_NAME (fields[i]) == name);
432 if (TREE_CODE (field) != TYPE_DECL
433 && !DECL_CLASS_TEMPLATE_P (field))
440 while (i < hi && DECL_NAME (fields[i]) == name);
448 field = TYPE_FIELDS (type);
450 #ifdef GATHER_STATISTICS
451 n_calls_lookup_field_1++;
452 #endif /* GATHER_STATISTICS */
453 for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field))
455 #ifdef GATHER_STATISTICS
457 #endif /* GATHER_STATISTICS */
458 gcc_assert (DECL_P (field));
459 if (DECL_NAME (field) == NULL_TREE
460 && ANON_AGGR_TYPE_P (TREE_TYPE (field)))
462 tree temp = lookup_field_1 (TREE_TYPE (field), name, want_type);
466 if (TREE_CODE (field) == USING_DECL)
468 /* We generally treat class-scope using-declarations as
469 ARM-style access specifications, because support for the
470 ISO semantics has not been implemented. So, in general,
471 there's no reason to return a USING_DECL, and the rest of
472 the compiler cannot handle that. Once the class is
473 defined, USING_DECLs are purged from TYPE_FIELDS; see
474 handle_using_decl. However, we make special efforts to
475 make using-declarations in class templates and class
476 template partial specializations work correctly. */
477 if (!DECL_DEPENDENT_P (field))
481 if (DECL_NAME (field) == name
483 || TREE_CODE (field) == TYPE_DECL
484 || DECL_CLASS_TEMPLATE_P (field)))
488 if (name == vptr_identifier)
490 /* Give the user what s/he thinks s/he wants. */
491 if (TYPE_POLYMORPHIC_P (type))
492 return TYPE_VFIELD (type);
497 /* Return the FUNCTION_DECL, RECORD_TYPE, UNION_TYPE, or
498 NAMESPACE_DECL corresponding to the innermost non-block scope. */
503 /* There are a number of cases we need to be aware of here:
504 current_class_type current_function_decl
511 Those last two make life interesting. If we're in a function which is
512 itself inside a class, we need decls to go into the fn's decls (our
513 second case below). But if we're in a class and the class itself is
514 inside a function, we need decls to go into the decls for the class. To
515 achieve this last goal, we must see if, when both current_class_ptr and
516 current_function_decl are set, the class was declared inside that
517 function. If so, we know to put the decls into the class's scope. */
518 if (current_function_decl && current_class_type
519 && ((DECL_FUNCTION_MEMBER_P (current_function_decl)
520 && same_type_p (DECL_CONTEXT (current_function_decl),
522 || (DECL_FRIEND_CONTEXT (current_function_decl)
523 && same_type_p (DECL_FRIEND_CONTEXT (current_function_decl),
524 current_class_type))))
525 return current_function_decl;
526 if (current_class_type)
527 return current_class_type;
528 if (current_function_decl)
529 return current_function_decl;
530 return current_namespace;
533 /* Returns nonzero if we are currently in a function scope. Note
534 that this function returns zero if we are within a local class, but
535 not within a member function body of the local class. */
538 at_function_scope_p (void)
540 tree cs = current_scope ();
541 return cs && TREE_CODE (cs) == FUNCTION_DECL;
544 /* Returns true if the innermost active scope is a class scope. */
547 at_class_scope_p (void)
549 tree cs = current_scope ();
550 return cs && TYPE_P (cs);
553 /* Returns true if the innermost active scope is a namespace scope. */
556 at_namespace_scope_p (void)
558 tree cs = current_scope ();
559 return cs && TREE_CODE (cs) == NAMESPACE_DECL;
562 /* Return the scope of DECL, as appropriate when doing name-lookup. */
565 context_for_name_lookup (tree decl)
569 For the purposes of name lookup, after the anonymous union
570 definition, the members of the anonymous union are considered to
571 have been defined in the scope in which the anonymous union is
573 tree context = DECL_CONTEXT (decl);
575 while (context && TYPE_P (context) && ANON_AGGR_TYPE_P (context))
576 context = TYPE_CONTEXT (context);
578 context = global_namespace;
583 /* The accessibility routines use BINFO_ACCESS for scratch space
584 during the computation of the accessibility of some declaration. */
586 #define BINFO_ACCESS(NODE) \
587 ((access_kind) ((TREE_PUBLIC (NODE) << 1) | TREE_PRIVATE (NODE)))
589 /* Set the access associated with NODE to ACCESS. */
591 #define SET_BINFO_ACCESS(NODE, ACCESS) \
592 ((TREE_PUBLIC (NODE) = ((ACCESS) & 2) != 0), \
593 (TREE_PRIVATE (NODE) = ((ACCESS) & 1) != 0))
595 /* Called from access_in_type via dfs_walk. Calculate the access to
596 DATA (which is really a DECL) in BINFO. */
599 dfs_access_in_type (tree binfo, void *data)
601 tree decl = (tree) data;
602 tree type = BINFO_TYPE (binfo);
603 access_kind access = ak_none;
605 if (context_for_name_lookup (decl) == type)
607 /* If we have descended to the scope of DECL, just note the
608 appropriate access. */
609 if (TREE_PRIVATE (decl))
611 else if (TREE_PROTECTED (decl))
612 access = ak_protected;
618 /* First, check for an access-declaration that gives us more
619 access to the DECL. The CONST_DECL for an enumeration
620 constant will not have DECL_LANG_SPECIFIC, and thus no
622 if (DECL_LANG_SPECIFIC (decl) && !DECL_DISCRIMINATOR_P (decl))
624 tree decl_access = purpose_member (type, DECL_ACCESS (decl));
628 decl_access = TREE_VALUE (decl_access);
630 if (decl_access == access_public_node)
632 else if (decl_access == access_protected_node)
633 access = ak_protected;
634 else if (decl_access == access_private_node)
645 VEC(tree,gc) *accesses;
647 /* Otherwise, scan our baseclasses, and pick the most favorable
649 accesses = BINFO_BASE_ACCESSES (binfo);
650 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
652 tree base_access = VEC_index (tree, accesses, i);
653 access_kind base_access_now = BINFO_ACCESS (base_binfo);
655 if (base_access_now == ak_none || base_access_now == ak_private)
656 /* If it was not accessible in the base, or only
657 accessible as a private member, we can't access it
659 base_access_now = ak_none;
660 else if (base_access == access_protected_node)
661 /* Public and protected members in the base become
663 base_access_now = ak_protected;
664 else if (base_access == access_private_node)
665 /* Public and protected members in the base become
667 base_access_now = ak_private;
669 /* See if the new access, via this base, gives more
670 access than our previous best access. */
671 if (base_access_now != ak_none
672 && (access == ak_none || base_access_now < access))
674 access = base_access_now;
676 /* If the new access is public, we can't do better. */
677 if (access == ak_public)
684 /* Note the access to DECL in TYPE. */
685 SET_BINFO_ACCESS (binfo, access);
690 /* Return the access to DECL in TYPE. */
693 access_in_type (tree type, tree decl)
695 tree binfo = TYPE_BINFO (type);
697 /* We must take into account
701 If a name can be reached by several paths through a multiple
702 inheritance graph, the access is that of the path that gives
705 The algorithm we use is to make a post-order depth-first traversal
706 of the base-class hierarchy. As we come up the tree, we annotate
707 each node with the most lenient access. */
708 dfs_walk_once (binfo, NULL, dfs_access_in_type, decl);
710 return BINFO_ACCESS (binfo);
713 /* Returns nonzero if it is OK to access DECL through an object
714 indicated by BINFO in the context of DERIVED. */
717 protected_accessible_p (tree decl, tree derived, tree binfo)
721 /* We're checking this clause from [class.access.base]
723 m as a member of N is protected, and the reference occurs in a
724 member or friend of class N, or in a member or friend of a
725 class P derived from N, where m as a member of P is public, private
728 Here DERIVED is a possible P, DECL is m and BINFO_TYPE (binfo) is N. */
730 /* If DERIVED isn't derived from N, then it can't be a P. */
731 if (!DERIVED_FROM_P (BINFO_TYPE (binfo), derived))
734 access = access_in_type (derived, decl);
736 /* If m is inaccessible in DERIVED, then it's not a P. */
737 if (access == ak_none)
742 When a friend or a member function of a derived class references
743 a protected nonstatic member of a base class, an access check
744 applies in addition to those described earlier in clause
745 _class.access_) Except when forming a pointer to member
746 (_expr.unary.op_), the access must be through a pointer to,
747 reference to, or object of the derived class itself (or any class
748 derived from that class) (_expr.ref_). If the access is to form
749 a pointer to member, the nested-name-specifier shall name the
750 derived class (or any class derived from that class). */
751 if (DECL_NONSTATIC_MEMBER_P (decl))
753 /* We can tell through what the reference is occurring by
754 chasing BINFO up to the root. */
756 while (BINFO_INHERITANCE_CHAIN (t))
757 t = BINFO_INHERITANCE_CHAIN (t);
759 if (!DERIVED_FROM_P (derived, BINFO_TYPE (t)))
766 /* Returns nonzero if SCOPE is a friend of a type which would be able
767 to access DECL through the object indicated by BINFO. */
770 friend_accessible_p (tree scope, tree decl, tree binfo)
772 tree befriending_classes;
778 if (TREE_CODE (scope) == FUNCTION_DECL
779 || DECL_FUNCTION_TEMPLATE_P (scope))
780 befriending_classes = DECL_BEFRIENDING_CLASSES (scope);
781 else if (TYPE_P (scope))
782 befriending_classes = CLASSTYPE_BEFRIENDING_CLASSES (scope);
786 for (t = befriending_classes; t; t = TREE_CHAIN (t))
787 if (protected_accessible_p (decl, TREE_VALUE (t), binfo))
790 /* Nested classes have the same access as their enclosing types, as
791 per DR 45 (this is a change from the standard). */
793 for (t = TYPE_CONTEXT (scope); t && TYPE_P (t); t = TYPE_CONTEXT (t))
794 if (protected_accessible_p (decl, t, binfo))
797 if (TREE_CODE (scope) == FUNCTION_DECL
798 || DECL_FUNCTION_TEMPLATE_P (scope))
800 /* Perhaps this SCOPE is a member of a class which is a
802 if (DECL_CLASS_SCOPE_P (scope)
803 && friend_accessible_p (DECL_CONTEXT (scope), decl, binfo))
806 /* Or an instantiation of something which is a friend. */
807 if (DECL_TEMPLATE_INFO (scope))
810 /* Increment processing_template_decl to make sure that
811 dependent_type_p works correctly. */
812 ++processing_template_decl;
813 ret = friend_accessible_p (DECL_TI_TEMPLATE (scope), decl, binfo);
814 --processing_template_decl;
822 /* Called via dfs_walk_once_accessible from accessible_p */
825 dfs_accessible_post (tree binfo, void *data ATTRIBUTE_UNUSED)
827 if (BINFO_ACCESS (binfo) != ak_none)
829 tree scope = current_scope ();
830 if (scope && TREE_CODE (scope) != NAMESPACE_DECL
831 && is_friend (BINFO_TYPE (binfo), scope))
838 /* DECL is a declaration from a base class of TYPE, which was the
839 class used to name DECL. Return nonzero if, in the current
840 context, DECL is accessible. If TYPE is actually a BINFO node,
841 then we can tell in what context the access is occurring by looking
842 at the most derived class along the path indicated by BINFO. If
843 CONSIDER_LOCAL is true, do consider special access the current
844 scope or friendship thereof we might have. */
847 accessible_p (tree type, tree decl, bool consider_local_p)
853 /* Nonzero if it's OK to access DECL if it has protected
854 accessibility in TYPE. */
855 int protected_ok = 0;
857 /* If this declaration is in a block or namespace scope, there's no
859 if (!TYPE_P (context_for_name_lookup (decl)))
862 /* There is no need to perform access checks inside a thunk. */
863 scope = current_scope ();
864 if (scope && DECL_THUNK_P (scope))
867 /* In a template declaration, we cannot be sure whether the
868 particular specialization that is instantiated will be a friend
869 or not. Therefore, all access checks are deferred until
870 instantiation. However, PROCESSING_TEMPLATE_DECL is set in the
871 parameter list for a template (because we may see dependent types
872 in default arguments for template parameters), and access
873 checking should be performed in the outermost parameter list. */
874 if (processing_template_decl
875 && (!processing_template_parmlist || processing_template_decl > 1))
881 type = BINFO_TYPE (type);
884 binfo = TYPE_BINFO (type);
886 /* [class.access.base]
888 A member m is accessible when named in class N if
890 --m as a member of N is public, or
892 --m as a member of N is private, and the reference occurs in a
893 member or friend of class N, or
895 --m as a member of N is protected, and the reference occurs in a
896 member or friend of class N, or in a member or friend of a
897 class P derived from N, where m as a member of P is private or
900 --there exists a base class B of N that is accessible at the point
901 of reference, and m is accessible when named in class B.
903 We walk the base class hierarchy, checking these conditions. */
905 if (consider_local_p)
907 /* Figure out where the reference is occurring. Check to see if
908 DECL is private or protected in this scope, since that will
909 determine whether protected access is allowed. */
910 if (current_class_type)
911 protected_ok = protected_accessible_p (decl,
912 current_class_type, binfo);
914 /* Now, loop through the classes of which we are a friend. */
916 protected_ok = friend_accessible_p (scope, decl, binfo);
919 /* Standardize the binfo that access_in_type will use. We don't
920 need to know what path was chosen from this point onwards. */
921 binfo = TYPE_BINFO (type);
923 /* Compute the accessibility of DECL in the class hierarchy
924 dominated by type. */
925 access = access_in_type (type, decl);
926 if (access == ak_public
927 || (access == ak_protected && protected_ok))
930 if (!consider_local_p)
933 /* Walk the hierarchy again, looking for a base class that allows
935 return dfs_walk_once_accessible (binfo, /*friends=*/true,
936 NULL, dfs_accessible_post, NULL)
940 struct lookup_field_info {
941 /* The type in which we're looking. */
943 /* The name of the field for which we're looking. */
945 /* If non-NULL, the current result of the lookup. */
947 /* The path to RVAL. */
949 /* If non-NULL, the lookup was ambiguous, and this is a list of the
952 /* If nonzero, we are looking for types, not data members. */
954 /* If something went wrong, a message indicating what. */
958 /* Nonzero for a class member means that it is shared between all objects
961 [class.member.lookup]:If the resulting set of declarations are not all
962 from sub-objects of the same type, or the set has a nonstatic member
963 and includes members from distinct sub-objects, there is an ambiguity
964 and the program is ill-formed.
966 This function checks that T contains no nonstatic members. */
969 shared_member_p (tree t)
971 if (TREE_CODE (t) == VAR_DECL || TREE_CODE (t) == TYPE_DECL \
972 || TREE_CODE (t) == CONST_DECL)
974 if (is_overloaded_fn (t))
977 for (; t; t = OVL_NEXT (t))
979 tree fn = OVL_CURRENT (t);
980 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
988 /* Routine to see if the sub-object denoted by the binfo PARENT can be
989 found as a base class and sub-object of the object denoted by
993 is_subobject_of_p (tree parent, tree binfo)
997 for (probe = parent; probe; probe = BINFO_INHERITANCE_CHAIN (probe))
1001 if (BINFO_VIRTUAL_P (probe))
1002 return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (binfo))
1008 /* DATA is really a struct lookup_field_info. Look for a field with
1009 the name indicated there in BINFO. If this function returns a
1010 non-NULL value it is the result of the lookup. Called from
1011 lookup_field via breadth_first_search. */
1014 lookup_field_r (tree binfo, void *data)
1016 struct lookup_field_info *lfi = (struct lookup_field_info *) data;
1017 tree type = BINFO_TYPE (binfo);
1018 tree nval = NULL_TREE;
1020 /* If this is a dependent base, don't look in it. */
1021 if (BINFO_DEPENDENT_BASE_P (binfo))
1024 /* If this base class is hidden by the best-known value so far, we
1025 don't need to look. */
1026 if (lfi->rval_binfo && BINFO_INHERITANCE_CHAIN (binfo) == lfi->rval_binfo
1027 && !BINFO_VIRTUAL_P (binfo))
1028 return dfs_skip_bases;
1030 /* First, look for a function. There can't be a function and a data
1031 member with the same name, and if there's a function and a type
1032 with the same name, the type is hidden by the function. */
1033 if (!lfi->want_type)
1035 int idx = lookup_fnfields_1 (type, lfi->name);
1037 nval = VEC_index (tree, CLASSTYPE_METHOD_VEC (type), idx);
1041 /* Look for a data member or type. */
1042 nval = lookup_field_1 (type, lfi->name, lfi->want_type);
1044 /* If there is no declaration with the indicated name in this type,
1045 then there's nothing to do. */
1049 /* If we're looking up a type (as with an elaborated type specifier)
1050 we ignore all non-types we find. */
1051 if (lfi->want_type && TREE_CODE (nval) != TYPE_DECL
1052 && !DECL_CLASS_TEMPLATE_P (nval))
1054 if (lfi->name == TYPE_IDENTIFIER (type))
1056 /* If the aggregate has no user defined constructors, we allow
1057 it to have fields with the same name as the enclosing type.
1058 If we are looking for that name, find the corresponding
1060 for (nval = TREE_CHAIN (nval); nval; nval = TREE_CHAIN (nval))
1061 if (DECL_NAME (nval) == lfi->name
1062 && TREE_CODE (nval) == TYPE_DECL)
1067 if (!nval && CLASSTYPE_NESTED_UTDS (type) != NULL)
1069 binding_entry e = binding_table_find (CLASSTYPE_NESTED_UTDS (type),
1072 nval = TYPE_MAIN_DECL (e->type);
1078 /* If the lookup already found a match, and the new value doesn't
1079 hide the old one, we might have an ambiguity. */
1081 && !is_subobject_of_p (lfi->rval_binfo, binfo))
1084 if (nval == lfi->rval && shared_member_p (nval))
1085 /* The two things are really the same. */
1087 else if (is_subobject_of_p (binfo, lfi->rval_binfo))
1088 /* The previous value hides the new one. */
1092 /* We have a real ambiguity. We keep a chain of all the
1094 if (!lfi->ambiguous && lfi->rval)
1096 /* This is the first time we noticed an ambiguity. Add
1097 what we previously thought was a reasonable candidate
1099 lfi->ambiguous = tree_cons (NULL_TREE, lfi->rval, NULL_TREE);
1100 TREE_TYPE (lfi->ambiguous) = error_mark_node;
1103 /* Add the new value. */
1104 lfi->ambiguous = tree_cons (NULL_TREE, nval, lfi->ambiguous);
1105 TREE_TYPE (lfi->ambiguous) = error_mark_node;
1106 lfi->errstr = G_("request for member %qD is ambiguous");
1112 lfi->rval_binfo = binfo;
1116 /* Don't look for constructors or destructors in base classes. */
1117 if (IDENTIFIER_CTOR_OR_DTOR_P (lfi->name))
1118 return dfs_skip_bases;
1122 /* Return a "baselink" with BASELINK_BINFO, BASELINK_ACCESS_BINFO,
1123 BASELINK_FUNCTIONS, and BASELINK_OPTYPE set to BINFO, ACCESS_BINFO,
1124 FUNCTIONS, and OPTYPE respectively. */
1127 build_baselink (tree binfo, tree access_binfo, tree functions, tree optype)
1131 gcc_assert (TREE_CODE (functions) == FUNCTION_DECL
1132 || TREE_CODE (functions) == TEMPLATE_DECL
1133 || TREE_CODE (functions) == TEMPLATE_ID_EXPR
1134 || TREE_CODE (functions) == OVERLOAD);
1135 gcc_assert (!optype || TYPE_P (optype));
1136 gcc_assert (TREE_TYPE (functions));
1138 baselink = make_node (BASELINK);
1139 TREE_TYPE (baselink) = TREE_TYPE (functions);
1140 BASELINK_BINFO (baselink) = binfo;
1141 BASELINK_ACCESS_BINFO (baselink) = access_binfo;
1142 BASELINK_FUNCTIONS (baselink) = functions;
1143 BASELINK_OPTYPE (baselink) = optype;
1148 /* Look for a member named NAME in an inheritance lattice dominated by
1149 XBASETYPE. If PROTECT is 0 or two, we do not check access. If it
1150 is 1, we enforce accessibility. If PROTECT is zero, then, for an
1151 ambiguous lookup, we return NULL. If PROTECT is 1, we issue error
1152 messages about inaccessible or ambiguous lookup. If PROTECT is 2,
1153 we return a TREE_LIST whose TREE_TYPE is error_mark_node and whose
1154 TREE_VALUEs are the list of ambiguous candidates.
1156 WANT_TYPE is 1 when we should only return TYPE_DECLs.
1158 If nothing can be found return NULL_TREE and do not issue an error. */
1161 lookup_member (tree xbasetype, tree name, int protect, bool want_type)
1163 tree rval, rval_binfo = NULL_TREE;
1164 tree type = NULL_TREE, basetype_path = NULL_TREE;
1165 struct lookup_field_info lfi;
1167 /* rval_binfo is the binfo associated with the found member, note,
1168 this can be set with useful information, even when rval is not
1169 set, because it must deal with ALL members, not just non-function
1170 members. It is used for ambiguity checking and the hidden
1171 checks. Whereas rval is only set if a proper (not hidden)
1172 non-function member is found. */
1174 const char *errstr = 0;
1176 if (name == 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 error (errstr, name, type);
1258 print_candidates (lfi.ambiguous);
1259 rval = error_mark_node;
1262 if (rval && is_overloaded_fn (rval))
1263 rval = build_baselink (rval_binfo, basetype_path, rval,
1264 (IDENTIFIER_TYPENAME_P (name)
1265 ? TREE_TYPE (name): NULL_TREE));
1269 /* Like lookup_member, except that if we find a function member we
1270 return NULL_TREE. */
1273 lookup_field (tree xbasetype, tree name, int protect, bool want_type)
1275 tree rval = lookup_member (xbasetype, name, protect, want_type);
1277 /* Ignore functions, but propagate the ambiguity list. */
1278 if (!error_operand_p (rval)
1279 && (rval && BASELINK_P (rval)))
1285 /* Like lookup_member, except that if we find a non-function member we
1286 return NULL_TREE. */
1289 lookup_fnfields (tree xbasetype, tree name, int protect)
1291 tree rval = lookup_member (xbasetype, name, protect, /*want_type=*/false);
1293 /* Ignore non-functions, but propagate the ambiguity list. */
1294 if (!error_operand_p (rval)
1295 && (rval && !BASELINK_P (rval)))
1301 /* Return the index in the CLASSTYPE_METHOD_VEC for CLASS_TYPE
1302 corresponding to "operator TYPE ()", or -1 if there is no such
1303 operator. Only CLASS_TYPE itself is searched; this routine does
1304 not scan the base classes of CLASS_TYPE. */
1307 lookup_conversion_operator (tree class_type, tree type)
1311 if (TYPE_HAS_CONVERSION (class_type))
1315 VEC(tree,gc) *methods = CLASSTYPE_METHOD_VEC (class_type);
1317 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
1318 VEC_iterate (tree, methods, i, fn); ++i)
1320 /* All the conversion operators come near the beginning of
1321 the class. Therefore, if FN is not a conversion
1322 operator, there is no matching conversion operator in
1324 fn = OVL_CURRENT (fn);
1325 if (!DECL_CONV_FN_P (fn))
1328 if (TREE_CODE (fn) == TEMPLATE_DECL)
1329 /* All the templated conversion functions are on the same
1330 slot, so remember it. */
1332 else if (same_type_p (DECL_CONV_FN_TYPE (fn), type))
1340 /* TYPE is a class type. Return the index of the fields within
1341 the method vector with name NAME, or -1 is no such field exists. */
1344 lookup_fnfields_1 (tree type, tree name)
1346 VEC(tree,gc) *method_vec;
1351 if (!CLASS_TYPE_P (type))
1354 if (COMPLETE_TYPE_P (type))
1356 if ((name == ctor_identifier
1357 || name == base_ctor_identifier
1358 || name == complete_ctor_identifier))
1360 if (CLASSTYPE_LAZY_DEFAULT_CTOR (type))
1361 lazily_declare_fn (sfk_constructor, type);
1362 if (CLASSTYPE_LAZY_COPY_CTOR (type))
1363 lazily_declare_fn (sfk_copy_constructor, type);
1364 if (CLASSTYPE_LAZY_MOVE_CTOR (type))
1365 lazily_declare_fn (sfk_move_constructor, type);
1367 else if (name == ansi_assopname(NOP_EXPR)
1368 && CLASSTYPE_LAZY_ASSIGNMENT_OP (type))
1369 lazily_declare_fn (sfk_assignment_operator, type);
1370 else if ((name == dtor_identifier
1371 || name == base_dtor_identifier
1372 || name == complete_dtor_identifier
1373 || name == deleting_dtor_identifier)
1374 && CLASSTYPE_LAZY_DESTRUCTOR (type))
1375 lazily_declare_fn (sfk_destructor, type);
1378 method_vec = CLASSTYPE_METHOD_VEC (type);
1382 #ifdef GATHER_STATISTICS
1383 n_calls_lookup_fnfields_1++;
1384 #endif /* GATHER_STATISTICS */
1386 /* Constructors are first... */
1387 if (name == ctor_identifier)
1389 fn = CLASSTYPE_CONSTRUCTORS (type);
1390 return fn ? CLASSTYPE_CONSTRUCTOR_SLOT : -1;
1392 /* and destructors are second. */
1393 if (name == dtor_identifier)
1395 fn = CLASSTYPE_DESTRUCTORS (type);
1396 return fn ? CLASSTYPE_DESTRUCTOR_SLOT : -1;
1398 if (IDENTIFIER_TYPENAME_P (name))
1399 return lookup_conversion_operator (type, TREE_TYPE (name));
1401 /* Skip the conversion operators. */
1402 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
1403 VEC_iterate (tree, method_vec, i, fn);
1405 if (!DECL_CONV_FN_P (OVL_CURRENT (fn)))
1408 /* If the type is complete, use binary search. */
1409 if (COMPLETE_TYPE_P (type))
1415 hi = VEC_length (tree, method_vec);
1420 #ifdef GATHER_STATISTICS
1421 n_outer_fields_searched++;
1422 #endif /* GATHER_STATISTICS */
1424 tmp = VEC_index (tree, method_vec, i);
1425 tmp = DECL_NAME (OVL_CURRENT (tmp));
1428 else if (tmp < name)
1435 for (; VEC_iterate (tree, method_vec, i, fn); ++i)
1437 #ifdef GATHER_STATISTICS
1438 n_outer_fields_searched++;
1439 #endif /* GATHER_STATISTICS */
1440 if (DECL_NAME (OVL_CURRENT (fn)) == name)
1447 /* Like lookup_fnfields_1, except that the name is extracted from
1448 FUNCTION, which is a FUNCTION_DECL or a TEMPLATE_DECL. */
1451 class_method_index_for_fn (tree class_type, tree function)
1453 gcc_assert (TREE_CODE (function) == FUNCTION_DECL
1454 || DECL_FUNCTION_TEMPLATE_P (function));
1456 return lookup_fnfields_1 (class_type,
1457 DECL_CONSTRUCTOR_P (function) ? ctor_identifier :
1458 DECL_DESTRUCTOR_P (function) ? dtor_identifier :
1459 DECL_NAME (function));
1463 /* DECL is the result of a qualified name lookup. QUALIFYING_SCOPE is
1464 the class or namespace used to qualify the name. CONTEXT_CLASS is
1465 the class corresponding to the object in which DECL will be used.
1466 Return a possibly modified version of DECL that takes into account
1469 In particular, consider an expression like `B::m' in the context of
1470 a derived class `D'. If `B::m' has been resolved to a BASELINK,
1471 then the most derived class indicated by the BASELINK_BINFO will be
1472 `B', not `D'. This function makes that adjustment. */
1475 adjust_result_of_qualified_name_lookup (tree decl,
1476 tree qualifying_scope,
1479 if (context_class && context_class != error_mark_node
1480 && CLASS_TYPE_P (context_class)
1481 && CLASS_TYPE_P (qualifying_scope)
1482 && DERIVED_FROM_P (qualifying_scope, context_class)
1483 && BASELINK_P (decl))
1487 /* Look for the QUALIFYING_SCOPE as a base of the CONTEXT_CLASS.
1488 Because we do not yet know which function will be chosen by
1489 overload resolution, we cannot yet check either accessibility
1490 or ambiguity -- in either case, the choice of a static member
1491 function might make the usage valid. */
1492 base = lookup_base (context_class, qualifying_scope,
1493 ba_unique | ba_quiet, NULL);
1496 BASELINK_ACCESS_BINFO (decl) = base;
1497 BASELINK_BINFO (decl)
1498 = lookup_base (base, BINFO_TYPE (BASELINK_BINFO (decl)),
1499 ba_unique | ba_quiet,
1508 /* Walk the class hierarchy within BINFO, in a depth-first traversal.
1509 PRE_FN is called in preorder, while POST_FN is called in postorder.
1510 If PRE_FN returns DFS_SKIP_BASES, child binfos will not be
1511 walked. If PRE_FN or POST_FN returns a different non-NULL value,
1512 that value is immediately returned and the walk is terminated. One
1513 of PRE_FN and POST_FN can be NULL. At each node, PRE_FN and
1514 POST_FN are passed the binfo to examine and the caller's DATA
1515 value. All paths are walked, thus virtual and morally virtual
1516 binfos can be multiply walked. */
1519 dfs_walk_all (tree binfo, tree (*pre_fn) (tree, void *),
1520 tree (*post_fn) (tree, void *), void *data)
1526 /* Call the pre-order walking function. */
1529 rval = pre_fn (binfo, data);
1532 if (rval == dfs_skip_bases)
1538 /* Find the next child binfo to walk. */
1539 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1541 rval = dfs_walk_all (base_binfo, pre_fn, post_fn, data);
1547 /* Call the post-order walking function. */
1550 rval = post_fn (binfo, data);
1551 gcc_assert (rval != dfs_skip_bases);
1558 /* Worker for dfs_walk_once. This behaves as dfs_walk_all, except
1559 that binfos are walked at most once. */
1562 dfs_walk_once_r (tree binfo, tree (*pre_fn) (tree, void *),
1563 tree (*post_fn) (tree, void *), void *data)
1569 /* Call the pre-order walking function. */
1572 rval = pre_fn (binfo, data);
1575 if (rval == dfs_skip_bases)
1582 /* Find the next child binfo to walk. */
1583 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1585 if (BINFO_VIRTUAL_P (base_binfo))
1587 if (BINFO_MARKED (base_binfo))
1589 BINFO_MARKED (base_binfo) = 1;
1592 rval = dfs_walk_once_r (base_binfo, pre_fn, post_fn, data);
1598 /* Call the post-order walking function. */
1601 rval = post_fn (binfo, data);
1602 gcc_assert (rval != dfs_skip_bases);
1609 /* Worker for dfs_walk_once. Recursively unmark the virtual base binfos of
1613 dfs_unmark_r (tree binfo)
1618 /* Process the basetypes. */
1619 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1621 if (BINFO_VIRTUAL_P (base_binfo))
1623 if (!BINFO_MARKED (base_binfo))
1625 BINFO_MARKED (base_binfo) = 0;
1627 /* Only walk, if it can contain more virtual bases. */
1628 if (CLASSTYPE_VBASECLASSES (BINFO_TYPE (base_binfo)))
1629 dfs_unmark_r (base_binfo);
1633 /* Like dfs_walk_all, except that binfos are not multiply walked. For
1634 non-diamond shaped hierarchies this is the same as dfs_walk_all.
1635 For diamond shaped hierarchies we must mark the virtual bases, to
1636 avoid multiple walks. */
1639 dfs_walk_once (tree binfo, tree (*pre_fn) (tree, void *),
1640 tree (*post_fn) (tree, void *), void *data)
1642 static int active = 0; /* We must not be called recursively. */
1645 gcc_assert (pre_fn || post_fn);
1646 gcc_assert (!active);
1649 if (!CLASSTYPE_DIAMOND_SHAPED_P (BINFO_TYPE (binfo)))
1650 /* We are not diamond shaped, and therefore cannot encounter the
1651 same binfo twice. */
1652 rval = dfs_walk_all (binfo, pre_fn, post_fn, data);
1655 rval = dfs_walk_once_r (binfo, pre_fn, post_fn, data);
1656 if (!BINFO_INHERITANCE_CHAIN (binfo))
1658 /* We are at the top of the hierarchy, and can use the
1659 CLASSTYPE_VBASECLASSES list for unmarking the virtual
1661 VEC(tree,gc) *vbases;
1665 for (vbases = CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)), ix = 0;
1666 VEC_iterate (tree, vbases, ix, base_binfo); ix++)
1667 BINFO_MARKED (base_binfo) = 0;
1670 dfs_unmark_r (binfo);
1678 /* Worker function for dfs_walk_once_accessible. Behaves like
1679 dfs_walk_once_r, except (a) FRIENDS_P is true if special
1680 access given by the current context should be considered, (b) ONCE
1681 indicates whether bases should be marked during traversal. */
1684 dfs_walk_once_accessible_r (tree binfo, bool friends_p, bool once,
1685 tree (*pre_fn) (tree, void *),
1686 tree (*post_fn) (tree, void *), void *data)
1688 tree rval = NULL_TREE;
1692 /* Call the pre-order walking function. */
1695 rval = pre_fn (binfo, data);
1698 if (rval == dfs_skip_bases)
1705 /* Find the next child binfo to walk. */
1706 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1708 bool mark = once && BINFO_VIRTUAL_P (base_binfo);
1710 if (mark && BINFO_MARKED (base_binfo))
1713 /* If the base is inherited via private or protected
1714 inheritance, then we can't see it, unless we are a friend of
1715 the current binfo. */
1716 if (BINFO_BASE_ACCESS (binfo, ix) != access_public_node)
1721 scope = current_scope ();
1723 || TREE_CODE (scope) == NAMESPACE_DECL
1724 || !is_friend (BINFO_TYPE (binfo), scope))
1729 BINFO_MARKED (base_binfo) = 1;
1731 rval = dfs_walk_once_accessible_r (base_binfo, friends_p, once,
1732 pre_fn, post_fn, data);
1738 /* Call the post-order walking function. */
1741 rval = post_fn (binfo, data);
1742 gcc_assert (rval != dfs_skip_bases);
1749 /* Like dfs_walk_once except that only accessible bases are walked.
1750 FRIENDS_P indicates whether friendship of the local context
1751 should be considered when determining accessibility. */
1754 dfs_walk_once_accessible (tree binfo, bool friends_p,
1755 tree (*pre_fn) (tree, void *),
1756 tree (*post_fn) (tree, void *), void *data)
1758 bool diamond_shaped = CLASSTYPE_DIAMOND_SHAPED_P (BINFO_TYPE (binfo));
1759 tree rval = dfs_walk_once_accessible_r (binfo, friends_p, diamond_shaped,
1760 pre_fn, post_fn, data);
1764 if (!BINFO_INHERITANCE_CHAIN (binfo))
1766 /* We are at the top of the hierarchy, and can use the
1767 CLASSTYPE_VBASECLASSES list for unmarking the virtual
1769 VEC(tree,gc) *vbases;
1773 for (vbases = CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo)), ix = 0;
1774 VEC_iterate (tree, vbases, ix, base_binfo); ix++)
1775 BINFO_MARKED (base_binfo) = 0;
1778 dfs_unmark_r (binfo);
1783 /* Check that virtual overrider OVERRIDER is acceptable for base function
1784 BASEFN. Issue diagnostic, and return zero, if unacceptable. */
1787 check_final_overrider (tree overrider, tree basefn)
1789 tree over_type = TREE_TYPE (overrider);
1790 tree base_type = TREE_TYPE (basefn);
1791 tree over_return = TREE_TYPE (over_type);
1792 tree base_return = TREE_TYPE (base_type);
1793 tree over_throw = TYPE_RAISES_EXCEPTIONS (over_type);
1794 tree base_throw = TYPE_RAISES_EXCEPTIONS (base_type);
1797 if (DECL_INVALID_OVERRIDER_P (overrider))
1800 if (same_type_p (base_return, over_return))
1802 else if ((CLASS_TYPE_P (over_return) && CLASS_TYPE_P (base_return))
1803 || (TREE_CODE (base_return) == TREE_CODE (over_return)
1804 && POINTER_TYPE_P (base_return)))
1806 /* Potentially covariant. */
1807 unsigned base_quals, over_quals;
1809 fail = !POINTER_TYPE_P (base_return);
1812 fail = cp_type_quals (base_return) != cp_type_quals (over_return);
1814 base_return = TREE_TYPE (base_return);
1815 over_return = TREE_TYPE (over_return);
1817 base_quals = cp_type_quals (base_return);
1818 over_quals = cp_type_quals (over_return);
1820 if ((base_quals & over_quals) != over_quals)
1823 if (CLASS_TYPE_P (base_return) && CLASS_TYPE_P (over_return))
1825 tree binfo = lookup_base (over_return, base_return,
1826 ba_check | ba_quiet, NULL);
1832 && can_convert (TREE_TYPE (base_type), TREE_TYPE (over_type)))
1833 /* GNU extension, allow trivial pointer conversions such as
1834 converting to void *, or qualification conversion. */
1836 /* can_convert will permit user defined conversion from a
1837 (reference to) class type. We must reject them. */
1838 over_return = non_reference (TREE_TYPE (over_type));
1839 if (CLASS_TYPE_P (over_return))
1843 warning (0, "deprecated covariant return type for %q+#D",
1845 warning (0, " overriding %q+#D", basefn);
1859 error ("invalid covariant return type for %q+#D", overrider);
1860 error (" overriding %q+#D", basefn);
1864 error ("conflicting return type specified for %q+#D", overrider);
1865 error (" overriding %q+#D", basefn);
1867 DECL_INVALID_OVERRIDER_P (overrider) = 1;
1871 /* Check throw specifier is at least as strict. */
1872 if (!comp_except_specs (base_throw, over_throw, 0))
1874 error ("looser throw specifier for %q+#F", overrider);
1875 error (" overriding %q+#F", basefn);
1876 DECL_INVALID_OVERRIDER_P (overrider) = 1;
1880 /* Check for conflicting type attributes. */
1881 if (!targetm.comp_type_attributes (over_type, base_type))
1883 error ("conflicting type attributes specified for %q+#D", overrider);
1884 error (" overriding %q+#D", basefn);
1885 DECL_INVALID_OVERRIDER_P (overrider) = 1;
1889 if (DECL_DELETED_FN (basefn) != DECL_DELETED_FN (overrider))
1891 if (DECL_DELETED_FN (overrider))
1893 error ("deleted function %q+D", overrider);
1894 error ("overriding non-deleted function %q+D", basefn);
1898 error ("non-deleted function %q+D", overrider);
1899 error ("overriding deleted function %q+D", basefn);
1906 /* Given a class TYPE, and a function decl FNDECL, look for
1907 virtual functions in TYPE's hierarchy which FNDECL overrides.
1908 We do not look in TYPE itself, only its bases.
1910 Returns nonzero, if we find any. Set FNDECL's DECL_VIRTUAL_P, if we
1911 find that it overrides anything.
1913 We check that every function which is overridden, is correctly
1917 look_for_overrides (tree type, tree fndecl)
1919 tree binfo = TYPE_BINFO (type);
1924 for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
1926 tree basetype = BINFO_TYPE (base_binfo);
1928 if (TYPE_POLYMORPHIC_P (basetype))
1929 found += look_for_overrides_r (basetype, fndecl);
1934 /* Look in TYPE for virtual functions with the same signature as
1938 look_for_overrides_here (tree type, tree fndecl)
1942 /* If there are no methods in TYPE (meaning that only implicitly
1943 declared methods will ever be provided for TYPE), then there are
1944 no virtual functions. */
1945 if (!CLASSTYPE_METHOD_VEC (type))
1948 if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fndecl))
1949 ix = CLASSTYPE_DESTRUCTOR_SLOT;
1951 ix = lookup_fnfields_1 (type, DECL_NAME (fndecl));
1954 tree fns = VEC_index (tree, CLASSTYPE_METHOD_VEC (type), ix);
1956 for (; fns; fns = OVL_NEXT (fns))
1958 tree fn = OVL_CURRENT (fns);
1960 if (!DECL_VIRTUAL_P (fn))
1961 /* Not a virtual. */;
1962 else if (DECL_CONTEXT (fn) != type)
1963 /* Introduced with a using declaration. */;
1964 else if (DECL_STATIC_FUNCTION_P (fndecl))
1966 tree btypes = TYPE_ARG_TYPES (TREE_TYPE (fn));
1967 tree dtypes = TYPE_ARG_TYPES (TREE_TYPE (fndecl));
1968 if (compparms (TREE_CHAIN (btypes), dtypes))
1971 else if (same_signature_p (fndecl, fn))
1978 /* Look in TYPE for virtual functions overridden by FNDECL. Check both
1979 TYPE itself and its bases. */
1982 look_for_overrides_r (tree type, tree fndecl)
1984 tree fn = look_for_overrides_here (type, fndecl);
1987 if (DECL_STATIC_FUNCTION_P (fndecl))
1989 /* A static member function cannot match an inherited
1990 virtual member function. */
1991 error ("%q+#D cannot be declared", fndecl);
1992 error (" since %q+#D declared in base class", fn);
1996 /* It's definitely virtual, even if not explicitly set. */
1997 DECL_VIRTUAL_P (fndecl) = 1;
1998 check_final_overrider (fndecl, fn);
2003 /* We failed to find one declared in this class. Look in its bases. */
2004 return look_for_overrides (type, fndecl);
2007 /* Called via dfs_walk from dfs_get_pure_virtuals. */
2010 dfs_get_pure_virtuals (tree binfo, void *data)
2012 tree type = (tree) data;
2014 /* We're not interested in primary base classes; the derived class
2015 of which they are a primary base will contain the information we
2017 if (!BINFO_PRIMARY_P (binfo))
2021 for (virtuals = BINFO_VIRTUALS (binfo);
2023 virtuals = TREE_CHAIN (virtuals))
2024 if (DECL_PURE_VIRTUAL_P (BV_FN (virtuals)))
2025 VEC_safe_push (tree, gc, CLASSTYPE_PURE_VIRTUALS (type),
2032 /* Set CLASSTYPE_PURE_VIRTUALS for TYPE. */
2035 get_pure_virtuals (tree type)
2037 /* Clear the CLASSTYPE_PURE_VIRTUALS list; whatever is already there
2038 is going to be overridden. */
2039 CLASSTYPE_PURE_VIRTUALS (type) = NULL;
2040 /* Now, run through all the bases which are not primary bases, and
2041 collect the pure virtual functions. We look at the vtable in
2042 each class to determine what pure virtual functions are present.
2043 (A primary base is not interesting because the derived class of
2044 which it is a primary base will contain vtable entries for the
2045 pure virtuals in the base class. */
2046 dfs_walk_once (TYPE_BINFO (type), NULL, dfs_get_pure_virtuals, type);
2049 /* Debug info for C++ classes can get very large; try to avoid
2050 emitting it everywhere.
2052 Note that this optimization wins even when the target supports
2053 BINCL (if only slightly), and reduces the amount of work for the
2057 maybe_suppress_debug_info (tree t)
2059 if (write_symbols == NO_DEBUG)
2062 /* We might have set this earlier in cp_finish_decl. */
2063 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 0;
2065 /* Always emit the information for each class every time. */
2066 if (flag_emit_class_debug_always)
2069 /* If we already know how we're handling this class, handle debug info
2071 if (CLASSTYPE_INTERFACE_KNOWN (t))
2073 if (CLASSTYPE_INTERFACE_ONLY (t))
2074 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 1;
2075 /* else don't set it. */
2077 /* If the class has a vtable, write out the debug info along with
2079 else if (TYPE_CONTAINS_VPTR_P (t))
2080 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t)) = 1;
2082 /* Otherwise, just emit the debug info normally. */
2085 /* Note that we want debugging information for a base class of a class
2086 whose vtable is being emitted. Normally, this would happen because
2087 calling the constructor for a derived class implies calling the
2088 constructors for all bases, which involve initializing the
2089 appropriate vptr with the vtable for the base class; but in the
2090 presence of optimization, this initialization may be optimized
2091 away, so we tell finish_vtable_vardecl that we want the debugging
2092 information anyway. */
2095 dfs_debug_mark (tree binfo, void *data ATTRIBUTE_UNUSED)
2097 tree t = BINFO_TYPE (binfo);
2099 if (CLASSTYPE_DEBUG_REQUESTED (t))
2100 return dfs_skip_bases;
2102 CLASSTYPE_DEBUG_REQUESTED (t) = 1;
2107 /* Write out the debugging information for TYPE, whose vtable is being
2108 emitted. Also walk through our bases and note that we want to
2109 write out information for them. This avoids the problem of not
2110 writing any debug info for intermediate basetypes whose
2111 constructors, and thus the references to their vtables, and thus
2112 the vtables themselves, were optimized away. */
2115 note_debug_info_needed (tree type)
2117 if (TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type)))
2119 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type)) = 0;
2120 rest_of_type_compilation (type, toplevel_bindings_p ());
2123 dfs_walk_all (TYPE_BINFO (type), dfs_debug_mark, NULL, 0);
2127 print_search_statistics (void)
2129 #ifdef GATHER_STATISTICS
2130 fprintf (stderr, "%d fields searched in %d[%d] calls to lookup_field[_1]\n",
2131 n_fields_searched, n_calls_lookup_field, n_calls_lookup_field_1);
2132 fprintf (stderr, "%d fnfields searched in %d calls to lookup_fnfields\n",
2133 n_outer_fields_searched, n_calls_lookup_fnfields);
2134 fprintf (stderr, "%d calls to get_base_type\n", n_calls_get_base_type);
2135 #else /* GATHER_STATISTICS */
2136 fprintf (stderr, "no search statistics\n");
2137 #endif /* GATHER_STATISTICS */
2141 reinit_search_statistics (void)
2143 #ifdef GATHER_STATISTICS
2144 n_fields_searched = 0;
2145 n_calls_lookup_field = 0, n_calls_lookup_field_1 = 0;
2146 n_calls_lookup_fnfields = 0, n_calls_lookup_fnfields_1 = 0;
2147 n_calls_get_base_type = 0;
2148 n_outer_fields_searched = 0;
2149 n_contexts_saved = 0;
2150 #endif /* GATHER_STATISTICS */
2153 /* Helper for lookup_conversions_r. TO_TYPE is the type converted to
2154 by a conversion op in base BINFO. VIRTUAL_DEPTH is nonzero if
2155 BINFO is morally virtual, and VIRTUALNESS is nonzero if virtual
2156 bases have been encountered already in the tree walk. PARENT_CONVS
2157 is the list of lists of conversion functions that could hide CONV
2158 and OTHER_CONVS is the list of lists of conversion functions that
2159 could hide or be hidden by CONV, should virtualness be involved in
2160 the hierarchy. Merely checking the conversion op's name is not
2161 enough because two conversion operators to the same type can have
2162 different names. Return nonzero if we are visible. */
2165 check_hidden_convs (tree binfo, int virtual_depth, int virtualness,
2166 tree to_type, tree parent_convs, tree other_convs)
2170 /* See if we are hidden by a parent conversion. */
2171 for (level = parent_convs; level; level = TREE_CHAIN (level))
2172 for (probe = TREE_VALUE (level); probe; probe = TREE_CHAIN (probe))
2173 if (same_type_p (to_type, TREE_TYPE (probe)))
2176 if (virtual_depth || virtualness)
2178 /* In a virtual hierarchy, we could be hidden, or could hide a
2179 conversion function on the other_convs list. */
2180 for (level = other_convs; level; level = TREE_CHAIN (level))
2186 if (!(virtual_depth || TREE_STATIC (level)))
2187 /* Neither is morally virtual, so cannot hide each other. */
2190 if (!TREE_VALUE (level))
2191 /* They evaporated away already. */
2194 they_hide_us = (virtual_depth
2195 && original_binfo (binfo, TREE_PURPOSE (level)));
2196 we_hide_them = (!they_hide_us && TREE_STATIC (level)
2197 && original_binfo (TREE_PURPOSE (level), binfo));
2199 if (!(we_hide_them || they_hide_us))
2200 /* Neither is within the other, so no hiding can occur. */
2203 for (prev = &TREE_VALUE (level), other = *prev; other;)
2205 if (same_type_p (to_type, TREE_TYPE (other)))
2208 /* We are hidden. */
2213 /* We hide the other one. */
2214 other = TREE_CHAIN (other);
2219 prev = &TREE_CHAIN (other);
2227 /* Helper for lookup_conversions_r. PARENT_CONVS is a list of lists
2228 of conversion functions, the first slot will be for the current
2229 binfo, if MY_CONVS is non-NULL. CHILD_CONVS is the list of lists
2230 of conversion functions from children of the current binfo,
2231 concatenated with conversions from elsewhere in the hierarchy --
2232 that list begins with OTHER_CONVS. Return a single list of lists
2233 containing only conversions from the current binfo and its
2237 split_conversions (tree my_convs, tree parent_convs,
2238 tree child_convs, tree other_convs)
2243 /* Remove the original other_convs portion from child_convs. */
2244 for (prev = NULL, t = child_convs;
2245 t != other_convs; prev = t, t = TREE_CHAIN (t))
2249 TREE_CHAIN (prev) = NULL_TREE;
2251 child_convs = NULL_TREE;
2253 /* Attach the child convs to any we had at this level. */
2256 my_convs = parent_convs;
2257 TREE_CHAIN (my_convs) = child_convs;
2260 my_convs = child_convs;
2265 /* Worker for lookup_conversions. Lookup conversion functions in
2266 BINFO and its children. VIRTUAL_DEPTH is nonzero, if BINFO is in
2267 a morally virtual base, and VIRTUALNESS is nonzero, if we've
2268 encountered virtual bases already in the tree walk. PARENT_CONVS &
2269 PARENT_TPL_CONVS are lists of list of conversions within parent
2270 binfos. OTHER_CONVS and OTHER_TPL_CONVS are conversions found
2271 elsewhere in the tree. Return the conversions found within this
2272 portion of the graph in CONVS and TPL_CONVS. Return nonzero is we
2273 encountered virtualness. We keep template and non-template
2274 conversions separate, to avoid unnecessary type comparisons.
2276 The located conversion functions are held in lists of lists. The
2277 TREE_VALUE of the outer list is the list of conversion functions
2278 found in a particular binfo. The TREE_PURPOSE of both the outer
2279 and inner lists is the binfo at which those conversions were
2280 found. TREE_STATIC is set for those lists within of morally
2281 virtual binfos. The TREE_VALUE of the inner list is the conversion
2282 function or overload itself. The TREE_TYPE of each inner list node
2283 is the converted-to type. */
2286 lookup_conversions_r (tree binfo,
2287 int virtual_depth, int virtualness,
2288 tree parent_convs, tree parent_tpl_convs,
2289 tree other_convs, tree other_tpl_convs,
2290 tree *convs, tree *tpl_convs)
2292 int my_virtualness = 0;
2293 tree my_convs = NULL_TREE;
2294 tree my_tpl_convs = NULL_TREE;
2295 tree child_convs = NULL_TREE;
2296 tree child_tpl_convs = NULL_TREE;
2299 VEC(tree,gc) *method_vec = CLASSTYPE_METHOD_VEC (BINFO_TYPE (binfo));
2302 /* If we have no conversion operators, then don't look. */
2303 if (!TYPE_HAS_CONVERSION (BINFO_TYPE (binfo)))
2305 *convs = *tpl_convs = NULL_TREE;
2310 if (BINFO_VIRTUAL_P (binfo))
2313 /* First, locate the unhidden ones at this level. */
2314 for (i = CLASSTYPE_FIRST_CONVERSION_SLOT;
2315 VEC_iterate (tree, method_vec, i, conv);
2318 tree cur = OVL_CURRENT (conv);
2320 if (!DECL_CONV_FN_P (cur))
2323 if (TREE_CODE (cur) == TEMPLATE_DECL)
2325 /* Only template conversions can be overloaded, and we must
2326 flatten them out and check each one individually. */
2329 for (tpls = conv; tpls; tpls = OVL_NEXT (tpls))
2331 tree tpl = OVL_CURRENT (tpls);
2332 tree type = DECL_CONV_FN_TYPE (tpl);
2334 if (check_hidden_convs (binfo, virtual_depth, virtualness,
2335 type, parent_tpl_convs, other_tpl_convs))
2337 my_tpl_convs = tree_cons (binfo, tpl, my_tpl_convs);
2338 TREE_TYPE (my_tpl_convs) = type;
2341 TREE_STATIC (my_tpl_convs) = 1;
2349 tree name = DECL_NAME (cur);
2351 if (!IDENTIFIER_MARKED (name))
2353 tree type = DECL_CONV_FN_TYPE (cur);
2355 if (check_hidden_convs (binfo, virtual_depth, virtualness,
2356 type, parent_convs, other_convs))
2358 my_convs = tree_cons (binfo, conv, my_convs);
2359 TREE_TYPE (my_convs) = type;
2362 TREE_STATIC (my_convs) = 1;
2365 IDENTIFIER_MARKED (name) = 1;
2373 parent_convs = tree_cons (binfo, my_convs, parent_convs);
2375 TREE_STATIC (parent_convs) = 1;
2380 parent_tpl_convs = tree_cons (binfo, my_tpl_convs, parent_tpl_convs);
2382 TREE_STATIC (parent_tpl_convs) = 1;
2385 child_convs = other_convs;
2386 child_tpl_convs = other_tpl_convs;
2388 /* Now iterate over each base, looking for more conversions. */
2389 for (i = 0; BINFO_BASE_ITERATE (binfo, i, base_binfo); i++)
2391 tree base_convs, base_tpl_convs;
2392 unsigned base_virtualness;
2394 base_virtualness = lookup_conversions_r (base_binfo,
2395 virtual_depth, virtualness,
2396 parent_convs, parent_tpl_convs,
2397 child_convs, child_tpl_convs,
2398 &base_convs, &base_tpl_convs);
2399 if (base_virtualness)
2400 my_virtualness = virtualness = 1;
2401 child_convs = chainon (base_convs, child_convs);
2402 child_tpl_convs = chainon (base_tpl_convs, child_tpl_convs);
2405 /* Unmark the conversions found at this level */
2406 for (conv = my_convs; conv; conv = TREE_CHAIN (conv))
2407 IDENTIFIER_MARKED (DECL_NAME (OVL_CURRENT (TREE_VALUE (conv)))) = 0;
2409 *convs = split_conversions (my_convs, parent_convs,
2410 child_convs, other_convs);
2411 *tpl_convs = split_conversions (my_tpl_convs, parent_tpl_convs,
2412 child_tpl_convs, other_tpl_convs);
2414 return my_virtualness;
2417 /* Return a TREE_LIST containing all the non-hidden user-defined
2418 conversion functions for TYPE (and its base-classes). The
2419 TREE_VALUE of each node is the FUNCTION_DECL of the conversion
2420 function. The TREE_PURPOSE is the BINFO from which the conversion
2421 functions in this node were selected. This function is effectively
2422 performing a set of member lookups as lookup_fnfield does, but
2423 using the type being converted to as the unique key, rather than the
2425 If LOOKUP_TEMPLATE_CONVS_P is TRUE, the returned TREE_LIST contains
2426 the non-hidden user-defined template conversion functions too. */
2429 lookup_conversions (tree type,
2430 bool lookup_template_convs_p)
2432 tree convs, tpl_convs;
2433 tree list = NULL_TREE;
2435 complete_type (type);
2436 if (!TYPE_BINFO (type))
2439 lookup_conversions_r (TYPE_BINFO (type), 0, 0,
2440 NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE,
2441 &convs, &tpl_convs);
2443 /* Flatten the list-of-lists */
2444 for (; convs; convs = TREE_CHAIN (convs))
2448 for (probe = TREE_VALUE (convs); probe; probe = next)
2450 next = TREE_CHAIN (probe);
2452 TREE_CHAIN (probe) = list;
2457 if (lookup_template_convs_p == false)
2458 tpl_convs = NULL_TREE;
2460 for (; tpl_convs; tpl_convs = TREE_CHAIN (tpl_convs))
2464 for (probe = TREE_VALUE (tpl_convs); probe; probe = next)
2466 next = TREE_CHAIN (probe);
2468 TREE_CHAIN (probe) = list;
2476 /* Returns the binfo of the first direct or indirect virtual base derived
2477 from BINFO, or NULL if binfo is not via virtual. */
2480 binfo_from_vbase (tree binfo)
2482 for (; binfo; binfo = BINFO_INHERITANCE_CHAIN (binfo))
2484 if (BINFO_VIRTUAL_P (binfo))
2490 /* Returns the binfo of the first direct or indirect virtual base derived
2491 from BINFO up to the TREE_TYPE, LIMIT, or NULL if binfo is not
2495 binfo_via_virtual (tree binfo, tree limit)
2497 if (limit && !CLASSTYPE_VBASECLASSES (limit))
2498 /* LIMIT has no virtual bases, so BINFO cannot be via one. */
2501 for (; binfo && !SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), limit);
2502 binfo = BINFO_INHERITANCE_CHAIN (binfo))
2504 if (BINFO_VIRTUAL_P (binfo))
2510 /* BINFO is a base binfo in the complete type BINFO_TYPE (HERE).
2511 Find the equivalent binfo within whatever graph HERE is located.
2512 This is the inverse of original_binfo. */
2515 copied_binfo (tree binfo, tree here)
2517 tree result = NULL_TREE;
2519 if (BINFO_VIRTUAL_P (binfo))
2523 for (t = here; BINFO_INHERITANCE_CHAIN (t);
2524 t = BINFO_INHERITANCE_CHAIN (t))
2527 result = binfo_for_vbase (BINFO_TYPE (binfo), BINFO_TYPE (t));
2529 else if (BINFO_INHERITANCE_CHAIN (binfo))
2535 cbinfo = copied_binfo (BINFO_INHERITANCE_CHAIN (binfo), here);
2536 for (ix = 0; BINFO_BASE_ITERATE (cbinfo, ix, base_binfo); ix++)
2537 if (SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo), BINFO_TYPE (binfo)))
2539 result = base_binfo;
2545 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (here), BINFO_TYPE (binfo)));
2549 gcc_assert (result);
2554 binfo_for_vbase (tree base, tree t)
2558 VEC(tree,gc) *vbases;
2560 for (vbases = CLASSTYPE_VBASECLASSES (t), ix = 0;
2561 VEC_iterate (tree, vbases, ix, binfo); ix++)
2562 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), base))
2567 /* BINFO is some base binfo of HERE, within some other
2568 hierarchy. Return the equivalent binfo, but in the hierarchy
2569 dominated by HERE. This is the inverse of copied_binfo. If BINFO
2570 is not a base binfo of HERE, returns NULL_TREE. */
2573 original_binfo (tree binfo, tree here)
2577 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo), BINFO_TYPE (here)))
2579 else if (BINFO_VIRTUAL_P (binfo))
2580 result = (CLASSTYPE_VBASECLASSES (BINFO_TYPE (here))
2581 ? binfo_for_vbase (BINFO_TYPE (binfo), BINFO_TYPE (here))
2583 else if (BINFO_INHERITANCE_CHAIN (binfo))
2587 base_binfos = original_binfo (BINFO_INHERITANCE_CHAIN (binfo), here);
2593 for (ix = 0; (base_binfo = BINFO_BASE_BINFO (base_binfos, ix)); ix++)
2594 if (SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo),
2595 BINFO_TYPE (binfo)))
2597 result = base_binfo;