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 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GCC.
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3, or (at your option)
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
23 /* High-level class interface. */
27 #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 int template_self_reference_p (tree
, tree
);
66 static tree
dfs_get_pure_virtuals (tree
, void *);
69 /* Variables for gathering statistics. */
70 #ifdef GATHER_STATISTICS
71 static int n_fields_searched
;
72 static int n_calls_lookup_field
, n_calls_lookup_field_1
;
73 static int n_calls_lookup_fnfields
, n_calls_lookup_fnfields_1
;
74 static int n_calls_get_base_type
;
75 static int n_outer_fields_searched
;
76 static int n_contexts_saved
;
77 #endif /* GATHER_STATISTICS */
80 /* Data for lookup_base and its workers. */
82 struct lookup_base_data_s
84 tree t
; /* type being searched. */
85 tree base
; /* The base type we're looking for. */
86 tree binfo
; /* Found binfo. */
87 bool via_virtual
; /* Found via a virtual path. */
88 bool ambiguous
; /* Found multiply ambiguous */
89 bool repeated_base
; /* Whether there are repeated bases in the
91 bool want_any
; /* Whether we want any matching binfo. */
94 /* Worker function for lookup_base. See if we've found the desired
95 base and update DATA_ (a pointer to LOOKUP_BASE_DATA_S). */
98 dfs_lookup_base (tree binfo
, void *data_
)
100 struct lookup_base_data_s
*data
= (struct lookup_base_data_s
*) data_
;
102 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), data
->base
))
108 = binfo_via_virtual (data
->binfo
, data
->t
) != NULL_TREE
;
110 if (!data
->repeated_base
)
111 /* If there are no repeated bases, we can stop now. */
114 if (data
->want_any
&& !data
->via_virtual
)
115 /* If this is a non-virtual base, then we can't do
119 return dfs_skip_bases
;
123 gcc_assert (binfo
!= data
->binfo
);
125 /* We've found more than one matching binfo. */
128 /* This is immediately ambiguous. */
129 data
->binfo
= NULL_TREE
;
130 data
->ambiguous
= true;
131 return error_mark_node
;
134 /* Prefer one via a non-virtual path. */
135 if (!binfo_via_virtual (binfo
, data
->t
))
138 data
->via_virtual
= false;
142 /* There must be repeated bases, otherwise we'd have stopped
143 on the first base we found. */
144 return dfs_skip_bases
;
151 /* Returns true if type BASE is accessible in T. (BASE is known to be
152 a (possibly non-proper) base class of T.) If CONSIDER_LOCAL_P is
153 true, consider any special access of the current scope, or access
154 bestowed by friendship. */
157 accessible_base_p (tree t
, tree base
, bool consider_local_p
)
161 /* [class.access.base]
163 A base class is said to be accessible if an invented public
164 member of the base class is accessible.
166 If BASE is a non-proper base, this condition is trivially
168 if (same_type_p (t
, base
))
170 /* Rather than inventing a public member, we use the implicit
171 public typedef created in the scope of every class. */
172 decl
= TYPE_FIELDS (base
);
173 while (!DECL_SELF_REFERENCE_P (decl
))
174 decl
= TREE_CHAIN (decl
);
175 while (ANON_AGGR_TYPE_P (t
))
176 t
= TYPE_CONTEXT (t
);
177 return accessible_p (t
, decl
, consider_local_p
);
180 /* Lookup BASE in the hierarchy dominated by T. Do access checking as
181 ACCESS specifies. Return the binfo we discover. If KIND_PTR is
182 non-NULL, fill with information about what kind of base we
185 If the base is inaccessible, or ambiguous, and the ba_quiet bit is
186 not set in ACCESS, then an error is issued and error_mark_node is
187 returned. If the ba_quiet bit is set, then no error is issued and
188 NULL_TREE is returned. */
191 lookup_base (tree t
, tree base
, base_access access
, base_kind
*kind_ptr
)
197 if (t
== error_mark_node
|| base
== error_mark_node
)
200 *kind_ptr
= bk_not_base
;
201 return error_mark_node
;
203 gcc_assert (TYPE_P (base
));
212 t
= complete_type (TYPE_MAIN_VARIANT (t
));
213 t_binfo
= TYPE_BINFO (t
);
216 base
= complete_type (TYPE_MAIN_VARIANT (base
));
220 struct lookup_base_data_s data
;
224 data
.binfo
= NULL_TREE
;
225 data
.ambiguous
= data
.via_virtual
= false;
226 data
.repeated_base
= CLASSTYPE_REPEATED_BASE_P (t
);
227 data
.want_any
= access
== ba_any
;
229 dfs_walk_once (t_binfo
, dfs_lookup_base
, NULL
, &data
);
233 bk
= data
.ambiguous
? bk_ambig
: bk_not_base
;
234 else if (binfo
== t_binfo
)
236 else if (data
.via_virtual
)
247 /* Check that the base is unambiguous and accessible. */
248 if (access
!= ba_any
)
255 if (!(access
& ba_quiet
))
257 error ("%qT is an ambiguous base of %qT", base
, t
);
258 binfo
= error_mark_node
;
263 if ((access
& ba_check_bit
)
264 /* If BASE is incomplete, then BASE and TYPE are probably
265 the same, in which case BASE is accessible. If they
266 are not the same, then TYPE is invalid. In that case,
267 there's no need to issue another error here, and
268 there's no implicit typedef to use in the code that
269 follows, so we skip the check. */
270 && COMPLETE_TYPE_P (base
)
271 && !accessible_base_p (t
, base
, !(access
& ba_ignore_scope
)))
273 if (!(access
& ba_quiet
))
275 error ("%qT is an inaccessible base of %qT", base
, t
);
276 binfo
= error_mark_node
;
280 bk
= bk_inaccessible
;
291 /* Data for dcast_base_hint walker. */
295 tree subtype
; /* The base type we're looking for. */
296 int virt_depth
; /* Number of virtual bases encountered from most
298 tree offset
; /* Best hint offset discovered so far. */
299 bool repeated_base
; /* Whether there are repeated bases in the
303 /* Worker for dcast_base_hint. Search for the base type being cast
307 dfs_dcast_hint_pre (tree binfo
, void *data_
)
309 struct dcast_data_s
*data
= (struct dcast_data_s
*) data_
;
311 if (BINFO_VIRTUAL_P (binfo
))
314 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), data
->subtype
))
316 if (data
->virt_depth
)
318 data
->offset
= ssize_int (-1);
322 data
->offset
= ssize_int (-3);
324 data
->offset
= BINFO_OFFSET (binfo
);
326 return data
->repeated_base
? dfs_skip_bases
: data
->offset
;
332 /* Worker for dcast_base_hint. Track the virtual depth. */
335 dfs_dcast_hint_post (tree binfo
, void *data_
)
337 struct dcast_data_s
*data
= (struct dcast_data_s
*) data_
;
339 if (BINFO_VIRTUAL_P (binfo
))
345 /* The dynamic cast runtime needs a hint about how the static SUBTYPE type
346 started from is related to the required TARGET type, in order to optimize
347 the inheritance graph search. This information is independent of the
348 current context, and ignores private paths, hence get_base_distance is
349 inappropriate. Return a TREE specifying the base offset, BOFF.
350 BOFF >= 0, there is only one public non-virtual SUBTYPE base at offset BOFF,
351 and there are no public virtual SUBTYPE bases.
352 BOFF == -1, SUBTYPE occurs as multiple public virtual or non-virtual bases.
353 BOFF == -2, SUBTYPE is not a public base.
354 BOFF == -3, SUBTYPE occurs as multiple public non-virtual bases. */
357 dcast_base_hint (tree subtype
, tree target
)
359 struct dcast_data_s data
;
361 data
.subtype
= subtype
;
363 data
.offset
= NULL_TREE
;
364 data
.repeated_base
= CLASSTYPE_REPEATED_BASE_P (target
);
366 dfs_walk_once_accessible (TYPE_BINFO (target
), /*friends=*/false,
367 dfs_dcast_hint_pre
, dfs_dcast_hint_post
, &data
);
368 return data
.offset
? data
.offset
: ssize_int (-2);
371 /* Search for a member with name NAME in a multiple inheritance
372 lattice specified by TYPE. If it does not exist, return NULL_TREE.
373 If the member is ambiguously referenced, return `error_mark_node'.
374 Otherwise, return a DECL with the indicated name. If WANT_TYPE is
375 true, type declarations are preferred. */
377 /* Do a 1-level search for NAME as a member of TYPE. The caller must
378 figure out whether it can access this field. (Since it is only one
379 level, this is reasonable.) */
382 lookup_field_1 (tree type
, tree name
, bool want_type
)
386 if (TREE_CODE (type
) == TEMPLATE_TYPE_PARM
387 || TREE_CODE (type
) == BOUND_TEMPLATE_TEMPLATE_PARM
388 || TREE_CODE (type
) == TYPENAME_TYPE
)
389 /* The TYPE_FIELDS of a TEMPLATE_TYPE_PARM and
390 BOUND_TEMPLATE_TEMPLATE_PARM are not fields at all;
391 instead TYPE_FIELDS is the TEMPLATE_PARM_INDEX. (Miraculously,
392 the code often worked even when we treated the index as a list
394 The TYPE_FIELDS of TYPENAME_TYPE is its TYPENAME_TYPE_FULLNAME. */
398 && DECL_LANG_SPECIFIC (TYPE_NAME (type
))
399 && DECL_SORTED_FIELDS (TYPE_NAME (type
)))
401 tree
*fields
= &DECL_SORTED_FIELDS (TYPE_NAME (type
))->elts
[0];
402 int lo
= 0, hi
= DECL_SORTED_FIELDS (TYPE_NAME (type
))->len
;
409 #ifdef GATHER_STATISTICS
411 #endif /* GATHER_STATISTICS */
413 if (DECL_NAME (fields
[i
]) > name
)
415 else if (DECL_NAME (fields
[i
]) < name
)
421 /* We might have a nested class and a field with the
422 same name; we sorted them appropriately via
423 field_decl_cmp, so just look for the first or last
424 field with this name. */
429 while (i
>= lo
&& DECL_NAME (fields
[i
]) == name
);
430 if (TREE_CODE (field
) != TYPE_DECL
431 && !DECL_CLASS_TEMPLATE_P (field
))
438 while (i
< hi
&& DECL_NAME (fields
[i
]) == name
);
446 field
= TYPE_FIELDS (type
);
448 #ifdef GATHER_STATISTICS
449 n_calls_lookup_field_1
++;
450 #endif /* GATHER_STATISTICS */
451 for (field
= TYPE_FIELDS (type
); field
; field
= TREE_CHAIN (field
))
453 #ifdef GATHER_STATISTICS
455 #endif /* GATHER_STATISTICS */
456 gcc_assert (DECL_P (field
));
457 if (DECL_NAME (field
) == NULL_TREE
458 && ANON_AGGR_TYPE_P (TREE_TYPE (field
)))
460 tree temp
= lookup_field_1 (TREE_TYPE (field
), name
, want_type
);
464 if (TREE_CODE (field
) == USING_DECL
)
466 /* We generally treat class-scope using-declarations as
467 ARM-style access specifications, because support for the
468 ISO semantics has not been implemented. So, in general,
469 there's no reason to return a USING_DECL, and the rest of
470 the compiler cannot handle that. Once the class is
471 defined, USING_DECLs are purged from TYPE_FIELDS; see
472 handle_using_decl. However, we make special efforts to
473 make using-declarations in class templates and class
474 template partial specializations work correctly. */
475 if (!DECL_DEPENDENT_P (field
))
479 if (DECL_NAME (field
) == name
481 || TREE_CODE (field
) == TYPE_DECL
482 || DECL_CLASS_TEMPLATE_P (field
)))
486 if (name
== vptr_identifier
)
488 /* Give the user what s/he thinks s/he wants. */
489 if (TYPE_POLYMORPHIC_P (type
))
490 return TYPE_VFIELD (type
);
495 /* Return the FUNCTION_DECL, RECORD_TYPE, UNION_TYPE, or
496 NAMESPACE_DECL corresponding to the innermost non-block scope. */
501 /* There are a number of cases we need to be aware of here:
502 current_class_type current_function_decl
509 Those last two make life interesting. If we're in a function which is
510 itself inside a class, we need decls to go into the fn's decls (our
511 second case below). But if we're in a class and the class itself is
512 inside a function, we need decls to go into the decls for the class. To
513 achieve this last goal, we must see if, when both current_class_ptr and
514 current_function_decl are set, the class was declared inside that
515 function. If so, we know to put the decls into the class's scope. */
516 if (current_function_decl
&& current_class_type
517 && ((DECL_FUNCTION_MEMBER_P (current_function_decl
)
518 && same_type_p (DECL_CONTEXT (current_function_decl
),
520 || (DECL_FRIEND_CONTEXT (current_function_decl
)
521 && same_type_p (DECL_FRIEND_CONTEXT (current_function_decl
),
522 current_class_type
))))
523 return current_function_decl
;
524 if (current_class_type
)
525 return current_class_type
;
526 if (current_function_decl
)
527 return current_function_decl
;
528 return current_namespace
;
531 /* Returns nonzero if we are currently in a function scope. Note
532 that this function returns zero if we are within a local class, but
533 not within a member function body of the local class. */
536 at_function_scope_p (void)
538 tree cs
= current_scope ();
539 return cs
&& TREE_CODE (cs
) == FUNCTION_DECL
;
542 /* Returns true if the innermost active scope is a class scope. */
545 at_class_scope_p (void)
547 tree cs
= current_scope ();
548 return cs
&& TYPE_P (cs
);
551 /* Returns true if the innermost active scope is a namespace scope. */
554 at_namespace_scope_p (void)
556 tree cs
= current_scope ();
557 return cs
&& TREE_CODE (cs
) == NAMESPACE_DECL
;
560 /* Return the scope of DECL, as appropriate when doing name-lookup. */
563 context_for_name_lookup (tree decl
)
567 For the purposes of name lookup, after the anonymous union
568 definition, the members of the anonymous union are considered to
569 have been defined in the scope in which the anonymous union is
571 tree context
= DECL_CONTEXT (decl
);
573 while (context
&& TYPE_P (context
) && ANON_AGGR_TYPE_P (context
))
574 context
= TYPE_CONTEXT (context
);
576 context
= global_namespace
;
581 /* The accessibility routines use BINFO_ACCESS for scratch space
582 during the computation of the accessibility of some declaration. */
584 #define BINFO_ACCESS(NODE) \
585 ((access_kind) ((TREE_PUBLIC (NODE) << 1) | TREE_PRIVATE (NODE)))
587 /* Set the access associated with NODE to ACCESS. */
589 #define SET_BINFO_ACCESS(NODE, ACCESS) \
590 ((TREE_PUBLIC (NODE) = ((ACCESS) & 2) != 0), \
591 (TREE_PRIVATE (NODE) = ((ACCESS) & 1) != 0))
593 /* Called from access_in_type via dfs_walk. Calculate the access to
594 DATA (which is really a DECL) in BINFO. */
597 dfs_access_in_type (tree binfo
, void *data
)
599 tree decl
= (tree
) data
;
600 tree type
= BINFO_TYPE (binfo
);
601 access_kind access
= ak_none
;
603 if (context_for_name_lookup (decl
) == type
)
605 /* If we have descended to the scope of DECL, just note the
606 appropriate access. */
607 if (TREE_PRIVATE (decl
))
609 else if (TREE_PROTECTED (decl
))
610 access
= ak_protected
;
616 /* First, check for an access-declaration that gives us more
617 access to the DECL. The CONST_DECL for an enumeration
618 constant will not have DECL_LANG_SPECIFIC, and thus no
620 if (DECL_LANG_SPECIFIC (decl
) && !DECL_DISCRIMINATOR_P (decl
))
622 tree decl_access
= purpose_member (type
, DECL_ACCESS (decl
));
626 decl_access
= TREE_VALUE (decl_access
);
628 if (decl_access
== access_public_node
)
630 else if (decl_access
== access_protected_node
)
631 access
= ak_protected
;
632 else if (decl_access
== access_private_node
)
643 VEC(tree
,gc
) *accesses
;
645 /* Otherwise, scan our baseclasses, and pick the most favorable
647 accesses
= BINFO_BASE_ACCESSES (binfo
);
648 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
650 tree base_access
= VEC_index (tree
, accesses
, i
);
651 access_kind base_access_now
= BINFO_ACCESS (base_binfo
);
653 if (base_access_now
== ak_none
|| base_access_now
== ak_private
)
654 /* If it was not accessible in the base, or only
655 accessible as a private member, we can't access it
657 base_access_now
= ak_none
;
658 else if (base_access
== access_protected_node
)
659 /* Public and protected members in the base become
661 base_access_now
= ak_protected
;
662 else if (base_access
== access_private_node
)
663 /* Public and protected members in the base become
665 base_access_now
= ak_private
;
667 /* See if the new access, via this base, gives more
668 access than our previous best access. */
669 if (base_access_now
!= ak_none
670 && (access
== ak_none
|| base_access_now
< access
))
672 access
= base_access_now
;
674 /* If the new access is public, we can't do better. */
675 if (access
== ak_public
)
682 /* Note the access to DECL in TYPE. */
683 SET_BINFO_ACCESS (binfo
, access
);
688 /* Return the access to DECL in TYPE. */
691 access_in_type (tree type
, tree decl
)
693 tree binfo
= TYPE_BINFO (type
);
695 /* We must take into account
699 If a name can be reached by several paths through a multiple
700 inheritance graph, the access is that of the path that gives
703 The algorithm we use is to make a post-order depth-first traversal
704 of the base-class hierarchy. As we come up the tree, we annotate
705 each node with the most lenient access. */
706 dfs_walk_once (binfo
, NULL
, dfs_access_in_type
, decl
);
708 return BINFO_ACCESS (binfo
);
711 /* Returns nonzero if it is OK to access DECL through an object
712 indicated by BINFO in the context of DERIVED. */
715 protected_accessible_p (tree decl
, tree derived
, tree binfo
)
719 /* We're checking this clause from [class.access.base]
721 m as a member of N is protected, and the reference occurs in a
722 member or friend of class N, or in a member or friend of a
723 class P derived from N, where m as a member of P is private or
726 Here DERIVED is a possible P and DECL is m. accessible_p will
727 iterate over various values of N, but the access to m in DERIVED
730 Note that I believe that the passage above is wrong, and should read
731 "...is private or protected or public"; otherwise you get bizarre results
732 whereby a public using-decl can prevent you from accessing a protected
733 member of a base. (jason 2000/02/28) */
735 /* If DERIVED isn't derived from m's class, then it can't be a P. */
736 if (!DERIVED_FROM_P (context_for_name_lookup (decl
), derived
))
739 access
= access_in_type (derived
, decl
);
741 /* If m is inaccessible in DERIVED, then it's not a P. */
742 if (access
== ak_none
)
747 When a friend or a member function of a derived class references
748 a protected nonstatic member of a base class, an access check
749 applies in addition to those described earlier in clause
750 _class.access_) Except when forming a pointer to member
751 (_expr.unary.op_), the access must be through a pointer to,
752 reference to, or object of the derived class itself (or any class
753 derived from that class) (_expr.ref_). If the access is to form
754 a pointer to member, the nested-name-specifier shall name the
755 derived class (or any class derived from that class). */
756 if (DECL_NONSTATIC_MEMBER_P (decl
))
758 /* We can tell through what the reference is occurring by
759 chasing BINFO up to the root. */
761 while (BINFO_INHERITANCE_CHAIN (t
))
762 t
= BINFO_INHERITANCE_CHAIN (t
);
764 if (!DERIVED_FROM_P (derived
, BINFO_TYPE (t
)))
771 /* Returns nonzero if SCOPE is a friend of a type which would be able
772 to access DECL through the object indicated by BINFO. */
775 friend_accessible_p (tree scope
, tree decl
, tree binfo
)
777 tree befriending_classes
;
783 if (TREE_CODE (scope
) == FUNCTION_DECL
784 || DECL_FUNCTION_TEMPLATE_P (scope
))
785 befriending_classes
= DECL_BEFRIENDING_CLASSES (scope
);
786 else if (TYPE_P (scope
))
787 befriending_classes
= CLASSTYPE_BEFRIENDING_CLASSES (scope
);
791 for (t
= befriending_classes
; t
; t
= TREE_CHAIN (t
))
792 if (protected_accessible_p (decl
, TREE_VALUE (t
), binfo
))
795 /* Nested classes have the same access as their enclosing types, as
796 per DR 45 (this is a change from the standard). */
798 for (t
= TYPE_CONTEXT (scope
); t
&& TYPE_P (t
); t
= TYPE_CONTEXT (t
))
799 if (protected_accessible_p (decl
, t
, binfo
))
802 if (TREE_CODE (scope
) == FUNCTION_DECL
803 || DECL_FUNCTION_TEMPLATE_P (scope
))
805 /* Perhaps this SCOPE is a member of a class which is a
807 if (DECL_CLASS_SCOPE_P (scope
)
808 && friend_accessible_p (DECL_CONTEXT (scope
), decl
, binfo
))
811 /* Or an instantiation of something which is a friend. */
812 if (DECL_TEMPLATE_INFO (scope
))
815 /* Increment processing_template_decl to make sure that
816 dependent_type_p works correctly. */
817 ++processing_template_decl
;
818 ret
= friend_accessible_p (DECL_TI_TEMPLATE (scope
), decl
, binfo
);
819 --processing_template_decl
;
827 /* Called via dfs_walk_once_accessible from accessible_p */
830 dfs_accessible_post (tree binfo
, void *data ATTRIBUTE_UNUSED
)
832 if (BINFO_ACCESS (binfo
) != ak_none
)
834 tree scope
= current_scope ();
835 if (scope
&& TREE_CODE (scope
) != NAMESPACE_DECL
836 && is_friend (BINFO_TYPE (binfo
), scope
))
843 /* DECL is a declaration from a base class of TYPE, which was the
844 class used to name DECL. Return nonzero if, in the current
845 context, DECL is accessible. If TYPE is actually a BINFO node,
846 then we can tell in what context the access is occurring by looking
847 at the most derived class along the path indicated by BINFO. If
848 CONSIDER_LOCAL is true, do consider special access the current
849 scope or friendship thereof we might have. */
852 accessible_p (tree type
, tree decl
, bool consider_local_p
)
858 /* Nonzero if it's OK to access DECL if it has protected
859 accessibility in TYPE. */
860 int protected_ok
= 0;
862 /* If this declaration is in a block or namespace scope, there's no
864 if (!TYPE_P (context_for_name_lookup (decl
)))
867 /* There is no need to perform access checks inside a thunk. */
868 scope
= current_scope ();
869 if (scope
&& DECL_THUNK_P (scope
))
872 /* In a template declaration, we cannot be sure whether the
873 particular specialization that is instantiated will be a friend
874 or not. Therefore, all access checks are deferred until
875 instantiation. However, PROCESSING_TEMPLATE_DECL is set in the
876 parameter list for a template (because we may see dependent types
877 in default arguments for template parameters), and access
878 checking should be performed in the outermost parameter list. */
879 if (processing_template_decl
880 && (!processing_template_parmlist
|| processing_template_decl
> 1))
886 type
= BINFO_TYPE (type
);
889 binfo
= TYPE_BINFO (type
);
891 /* [class.access.base]
893 A member m is accessible when named in class N if
895 --m as a member of N is public, or
897 --m as a member of N is private, and the reference occurs in a
898 member or friend of class N, or
900 --m as a member of N is protected, and the reference occurs in a
901 member or friend of class N, or in a member or friend of a
902 class P derived from N, where m as a member of P is private or
905 --there exists a base class B of N that is accessible at the point
906 of reference, and m is accessible when named in class B.
908 We walk the base class hierarchy, checking these conditions. */
910 if (consider_local_p
)
912 /* Figure out where the reference is occurring. Check to see if
913 DECL is private or protected in this scope, since that will
914 determine whether protected access is allowed. */
915 if (current_class_type
)
916 protected_ok
= protected_accessible_p (decl
,
917 current_class_type
, binfo
);
919 /* Now, loop through the classes of which we are a friend. */
921 protected_ok
= friend_accessible_p (scope
, decl
, binfo
);
924 /* Standardize the binfo that access_in_type will use. We don't
925 need to know what path was chosen from this point onwards. */
926 binfo
= TYPE_BINFO (type
);
928 /* Compute the accessibility of DECL in the class hierarchy
929 dominated by type. */
930 access
= access_in_type (type
, decl
);
931 if (access
== ak_public
932 || (access
== ak_protected
&& protected_ok
))
935 if (!consider_local_p
)
938 /* Walk the hierarchy again, looking for a base class that allows
940 return dfs_walk_once_accessible (binfo
, /*friends=*/true,
941 NULL
, dfs_accessible_post
, NULL
)
945 struct lookup_field_info
{
946 /* The type in which we're looking. */
948 /* The name of the field for which we're looking. */
950 /* If non-NULL, the current result of the lookup. */
952 /* The path to RVAL. */
954 /* If non-NULL, the lookup was ambiguous, and this is a list of the
957 /* If nonzero, we are looking for types, not data members. */
959 /* If something went wrong, a message indicating what. */
963 /* Within the scope of a template class, you can refer to the to the
964 current specialization with the name of the template itself. For
967 template <typename T> struct S { S* sp; }
969 Returns nonzero if DECL is such a declaration in a class TYPE. */
972 template_self_reference_p (tree type
, tree decl
)
974 return (CLASSTYPE_USE_TEMPLATE (type
)
975 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type
))
976 && TREE_CODE (decl
) == TYPE_DECL
977 && DECL_ARTIFICIAL (decl
)
978 && DECL_NAME (decl
) == constructor_name (type
));
981 /* Nonzero for a class member means that it is shared between all objects
984 [class.member.lookup]:If the resulting set of declarations are not all
985 from sub-objects of the same type, or the set has a nonstatic member
986 and includes members from distinct sub-objects, there is an ambiguity
987 and the program is ill-formed.
989 This function checks that T contains no nonstatic members. */
992 shared_member_p (tree t
)
994 if (TREE_CODE (t
) == VAR_DECL
|| TREE_CODE (t
) == TYPE_DECL \
995 || TREE_CODE (t
) == CONST_DECL
)
997 if (is_overloaded_fn (t
))
999 for (; t
; t
= OVL_NEXT (t
))
1001 tree fn
= OVL_CURRENT (t
);
1002 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
1010 /* Routine to see if the sub-object denoted by the binfo PARENT can be
1011 found as a base class and sub-object of the object denoted by
1015 is_subobject_of_p (tree parent
, tree binfo
)
1019 for (probe
= parent
; probe
; probe
= BINFO_INHERITANCE_CHAIN (probe
))
1023 if (BINFO_VIRTUAL_P (probe
))
1024 return (binfo_for_vbase (BINFO_TYPE (probe
), BINFO_TYPE (binfo
))
1030 /* DATA is really a struct lookup_field_info. Look for a field with
1031 the name indicated there in BINFO. If this function returns a
1032 non-NULL value it is the result of the lookup. Called from
1033 lookup_field via breadth_first_search. */
1036 lookup_field_r (tree binfo
, void *data
)
1038 struct lookup_field_info
*lfi
= (struct lookup_field_info
*) data
;
1039 tree type
= BINFO_TYPE (binfo
);
1040 tree nval
= NULL_TREE
;
1042 /* If this is a dependent base, don't look in it. */
1043 if (BINFO_DEPENDENT_BASE_P (binfo
))
1046 /* If this base class is hidden by the best-known value so far, we
1047 don't need to look. */
1048 if (lfi
->rval_binfo
&& BINFO_INHERITANCE_CHAIN (binfo
) == lfi
->rval_binfo
1049 && !BINFO_VIRTUAL_P (binfo
))
1050 return dfs_skip_bases
;
1052 /* First, look for a function. There can't be a function and a data
1053 member with the same name, and if there's a function and a type
1054 with the same name, the type is hidden by the function. */
1055 if (!lfi
->want_type
)
1057 int idx
= lookup_fnfields_1 (type
, lfi
->name
);
1059 nval
= VEC_index (tree
, CLASSTYPE_METHOD_VEC (type
), idx
);
1063 /* Look for a data member or type. */
1064 nval
= lookup_field_1 (type
, lfi
->name
, lfi
->want_type
);
1066 /* If there is no declaration with the indicated name in this type,
1067 then there's nothing to do. */
1071 /* If we're looking up a type (as with an elaborated type specifier)
1072 we ignore all non-types we find. */
1073 if (lfi
->want_type
&& TREE_CODE (nval
) != TYPE_DECL
1074 && !DECL_CLASS_TEMPLATE_P (nval
))
1076 if (lfi
->name
== TYPE_IDENTIFIER (type
))
1078 /* If the aggregate has no user defined constructors, we allow
1079 it to have fields with the same name as the enclosing type.
1080 If we are looking for that name, find the corresponding
1082 for (nval
= TREE_CHAIN (nval
); nval
; nval
= TREE_CHAIN (nval
))
1083 if (DECL_NAME (nval
) == lfi
->name
1084 && TREE_CODE (nval
) == TYPE_DECL
)
1089 if (!nval
&& CLASSTYPE_NESTED_UTDS (type
) != NULL
)
1091 binding_entry e
= binding_table_find (CLASSTYPE_NESTED_UTDS (type
),
1094 nval
= TYPE_MAIN_DECL (e
->type
);
1100 /* You must name a template base class with a template-id. */
1101 if (!same_type_p (type
, lfi
->type
)
1102 && template_self_reference_p (type
, nval
))
1105 /* If the lookup already found a match, and the new value doesn't
1106 hide the old one, we might have an ambiguity. */
1108 && !is_subobject_of_p (lfi
->rval_binfo
, binfo
))
1111 if (nval
== lfi
->rval
&& shared_member_p (nval
))
1112 /* The two things are really the same. */
1114 else if (is_subobject_of_p (binfo
, lfi
->rval_binfo
))
1115 /* The previous value hides the new one. */
1119 /* We have a real ambiguity. We keep a chain of all the
1121 if (!lfi
->ambiguous
&& lfi
->rval
)
1123 /* This is the first time we noticed an ambiguity. Add
1124 what we previously thought was a reasonable candidate
1126 lfi
->ambiguous
= tree_cons (NULL_TREE
, lfi
->rval
, NULL_TREE
);
1127 TREE_TYPE (lfi
->ambiguous
) = error_mark_node
;
1130 /* Add the new value. */
1131 lfi
->ambiguous
= tree_cons (NULL_TREE
, nval
, lfi
->ambiguous
);
1132 TREE_TYPE (lfi
->ambiguous
) = error_mark_node
;
1133 lfi
->errstr
= "request for member %qD is ambiguous";
1139 lfi
->rval_binfo
= binfo
;
1143 /* Don't look for constructors or destructors in base classes. */
1144 if (IDENTIFIER_CTOR_OR_DTOR_P (lfi
->name
))
1145 return dfs_skip_bases
;
1149 /* Return a "baselink" with BASELINK_BINFO, BASELINK_ACCESS_BINFO,
1150 BASELINK_FUNCTIONS, and BASELINK_OPTYPE set to BINFO, ACCESS_BINFO,
1151 FUNCTIONS, and OPTYPE respectively. */
1154 build_baselink (tree binfo
, tree access_binfo
, tree functions
, tree optype
)
1158 gcc_assert (TREE_CODE (functions
) == FUNCTION_DECL
1159 || TREE_CODE (functions
) == TEMPLATE_DECL
1160 || TREE_CODE (functions
) == TEMPLATE_ID_EXPR
1161 || TREE_CODE (functions
) == OVERLOAD
);
1162 gcc_assert (!optype
|| TYPE_P (optype
));
1163 gcc_assert (TREE_TYPE (functions
));
1165 baselink
= make_node (BASELINK
);
1166 TREE_TYPE (baselink
) = TREE_TYPE (functions
);
1167 BASELINK_BINFO (baselink
) = binfo
;
1168 BASELINK_ACCESS_BINFO (baselink
) = access_binfo
;
1169 BASELINK_FUNCTIONS (baselink
) = functions
;
1170 BASELINK_OPTYPE (baselink
) = optype
;
1175 /* Look for a member named NAME in an inheritance lattice dominated by
1176 XBASETYPE. If PROTECT is 0 or two, we do not check access. If it
1177 is 1, we enforce accessibility. If PROTECT is zero, then, for an
1178 ambiguous lookup, we return NULL. If PROTECT is 1, we issue error
1179 messages about inaccessible or ambiguous lookup. If PROTECT is 2,
1180 we return a TREE_LIST whose TREE_TYPE is error_mark_node and whose
1181 TREE_VALUEs are the list of ambiguous candidates.
1183 WANT_TYPE is 1 when we should only return TYPE_DECLs.
1185 If nothing can be found return NULL_TREE and do not issue an error. */
1188 lookup_member (tree xbasetype
, tree name
, int protect
, bool want_type
)
1190 tree rval
, rval_binfo
= NULL_TREE
;
1191 tree type
= NULL_TREE
, basetype_path
= NULL_TREE
;
1192 struct lookup_field_info lfi
;
1194 /* rval_binfo is the binfo associated with the found member, note,
1195 this can be set with useful information, even when rval is not
1196 set, because it must deal with ALL members, not just non-function
1197 members. It is used for ambiguity checking and the hidden
1198 checks. Whereas rval is only set if a proper (not hidden)
1199 non-function member is found. */
1201 const char *errstr
= 0;
1203 if (name
== error_mark_node
)
1206 gcc_assert (TREE_CODE (name
) == IDENTIFIER_NODE
);
1208 if (TREE_CODE (xbasetype
) == TREE_BINFO
)
1210 type
= BINFO_TYPE (xbasetype
);
1211 basetype_path
= xbasetype
;
1215 if (!IS_AGGR_TYPE_CODE (TREE_CODE (xbasetype
)))
1218 xbasetype
= NULL_TREE
;
1221 type
= complete_type (type
);
1223 basetype_path
= TYPE_BINFO (type
);
1228 #ifdef GATHER_STATISTICS
1229 n_calls_lookup_field
++;
1230 #endif /* GATHER_STATISTICS */
1232 memset (&lfi
, 0, sizeof (lfi
));
1235 lfi
.want_type
= want_type
;
1236 dfs_walk_all (basetype_path
, &lookup_field_r
, NULL
, &lfi
);
1238 rval_binfo
= lfi
.rval_binfo
;
1240 type
= BINFO_TYPE (rval_binfo
);
1241 errstr
= lfi
.errstr
;
1243 /* If we are not interested in ambiguities, don't report them;
1244 just return NULL_TREE. */
1245 if (!protect
&& lfi
.ambiguous
)
1251 return lfi
.ambiguous
;
1258 In the case of overloaded function names, access control is
1259 applied to the function selected by overloaded resolution.
1261 We cannot check here, even if RVAL is only a single non-static
1262 member function, since we do not know what the "this" pointer
1265 class A { protected: void f(); };
1266 class B : public A {
1273 only the first call to "f" is valid. However, if the function is
1274 static, we can check. */
1276 && !really_overloaded_fn (rval
)
1277 && !(TREE_CODE (rval
) == FUNCTION_DECL
1278 && DECL_NONSTATIC_MEMBER_FUNCTION_P (rval
)))
1279 perform_or_defer_access_check (basetype_path
, rval
, rval
);
1281 if (errstr
&& protect
)
1283 error (errstr
, name
, type
);
1285 print_candidates (lfi
.ambiguous
);
1286 rval
= error_mark_node
;
1289 if (rval
&& is_overloaded_fn (rval
))
1290 rval
= build_baselink (rval_binfo
, basetype_path
, rval
,
1291 (IDENTIFIER_TYPENAME_P (name
)
1292 ? TREE_TYPE (name
): NULL_TREE
));
1296 /* Like lookup_member, except that if we find a function member we
1297 return NULL_TREE. */
1300 lookup_field (tree xbasetype
, tree name
, int protect
, bool want_type
)
1302 tree rval
= lookup_member (xbasetype
, name
, protect
, want_type
);
1304 /* Ignore functions, but propagate the ambiguity list. */
1305 if (!error_operand_p (rval
)
1306 && (rval
&& BASELINK_P (rval
)))
1312 /* Like lookup_member, except that if we find a non-function member we
1313 return NULL_TREE. */
1316 lookup_fnfields (tree xbasetype
, tree name
, int protect
)
1318 tree rval
= lookup_member (xbasetype
, name
, protect
, /*want_type=*/false);
1320 /* Ignore non-functions, but propagate the ambiguity list. */
1321 if (!error_operand_p (rval
)
1322 && (rval
&& !BASELINK_P (rval
)))
1328 /* Return the index in the CLASSTYPE_METHOD_VEC for CLASS_TYPE
1329 corresponding to "operator TYPE ()", or -1 if there is no such
1330 operator. Only CLASS_TYPE itself is searched; this routine does
1331 not scan the base classes of CLASS_TYPE. */
1334 lookup_conversion_operator (tree class_type
, tree type
)
1338 if (TYPE_HAS_CONVERSION (class_type
))
1342 VEC(tree
,gc
) *methods
= CLASSTYPE_METHOD_VEC (class_type
);
1344 for (i
= CLASSTYPE_FIRST_CONVERSION_SLOT
;
1345 VEC_iterate (tree
, methods
, i
, fn
); ++i
)
1347 /* All the conversion operators come near the beginning of
1348 the class. Therefore, if FN is not a conversion
1349 operator, there is no matching conversion operator in
1351 fn
= OVL_CURRENT (fn
);
1352 if (!DECL_CONV_FN_P (fn
))
1355 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
1356 /* All the templated conversion functions are on the same
1357 slot, so remember it. */
1359 else if (same_type_p (DECL_CONV_FN_TYPE (fn
), type
))
1367 /* TYPE is a class type. Return the index of the fields within
1368 the method vector with name NAME, or -1 is no such field exists. */
1371 lookup_fnfields_1 (tree type
, tree name
)
1373 VEC(tree
,gc
) *method_vec
;
1378 if (!CLASS_TYPE_P (type
))
1381 if (COMPLETE_TYPE_P (type
))
1383 if ((name
== ctor_identifier
1384 || name
== base_ctor_identifier
1385 || name
== complete_ctor_identifier
))
1387 if (CLASSTYPE_LAZY_DEFAULT_CTOR (type
))
1388 lazily_declare_fn (sfk_constructor
, type
);
1389 if (CLASSTYPE_LAZY_COPY_CTOR (type
))
1390 lazily_declare_fn (sfk_copy_constructor
, type
);
1392 else if (name
== ansi_assopname(NOP_EXPR
)
1393 && CLASSTYPE_LAZY_ASSIGNMENT_OP (type
))
1394 lazily_declare_fn (sfk_assignment_operator
, type
);
1395 else if ((name
== dtor_identifier
1396 || name
== base_dtor_identifier
1397 || name
== complete_dtor_identifier
1398 || name
== deleting_dtor_identifier
)
1399 && CLASSTYPE_LAZY_DESTRUCTOR (type
))
1400 lazily_declare_fn (sfk_destructor
, type
);
1403 method_vec
= CLASSTYPE_METHOD_VEC (type
);
1407 #ifdef GATHER_STATISTICS
1408 n_calls_lookup_fnfields_1
++;
1409 #endif /* GATHER_STATISTICS */
1411 /* Constructors are first... */
1412 if (name
== ctor_identifier
)
1414 fn
= CLASSTYPE_CONSTRUCTORS (type
);
1415 return fn
? CLASSTYPE_CONSTRUCTOR_SLOT
: -1;
1417 /* and destructors are second. */
1418 if (name
== dtor_identifier
)
1420 fn
= CLASSTYPE_DESTRUCTORS (type
);
1421 return fn
? CLASSTYPE_DESTRUCTOR_SLOT
: -1;
1423 if (IDENTIFIER_TYPENAME_P (name
))
1424 return lookup_conversion_operator (type
, TREE_TYPE (name
));
1426 /* Skip the conversion operators. */
1427 for (i
= CLASSTYPE_FIRST_CONVERSION_SLOT
;
1428 VEC_iterate (tree
, method_vec
, i
, fn
);
1430 if (!DECL_CONV_FN_P (OVL_CURRENT (fn
)))
1433 /* If the type is complete, use binary search. */
1434 if (COMPLETE_TYPE_P (type
))
1440 hi
= VEC_length (tree
, method_vec
);
1445 #ifdef GATHER_STATISTICS
1446 n_outer_fields_searched
++;
1447 #endif /* GATHER_STATISTICS */
1449 tmp
= VEC_index (tree
, method_vec
, i
);
1450 tmp
= DECL_NAME (OVL_CURRENT (tmp
));
1453 else if (tmp
< name
)
1460 for (; VEC_iterate (tree
, method_vec
, i
, fn
); ++i
)
1462 #ifdef GATHER_STATISTICS
1463 n_outer_fields_searched
++;
1464 #endif /* GATHER_STATISTICS */
1465 if (DECL_NAME (OVL_CURRENT (fn
)) == name
)
1472 /* Like lookup_fnfields_1, except that the name is extracted from
1473 FUNCTION, which is a FUNCTION_DECL or a TEMPLATE_DECL. */
1476 class_method_index_for_fn (tree class_type
, tree function
)
1478 gcc_assert (TREE_CODE (function
) == FUNCTION_DECL
1479 || DECL_FUNCTION_TEMPLATE_P (function
));
1481 return lookup_fnfields_1 (class_type
,
1482 DECL_CONSTRUCTOR_P (function
) ? ctor_identifier
:
1483 DECL_DESTRUCTOR_P (function
) ? dtor_identifier
:
1484 DECL_NAME (function
));
1488 /* DECL is the result of a qualified name lookup. QUALIFYING_SCOPE is
1489 the class or namespace used to qualify the name. CONTEXT_CLASS is
1490 the class corresponding to the object in which DECL will be used.
1491 Return a possibly modified version of DECL that takes into account
1494 In particular, consider an expression like `B::m' in the context of
1495 a derived class `D'. If `B::m' has been resolved to a BASELINK,
1496 then the most derived class indicated by the BASELINK_BINFO will be
1497 `B', not `D'. This function makes that adjustment. */
1500 adjust_result_of_qualified_name_lookup (tree decl
,
1501 tree qualifying_scope
,
1504 if (context_class
&& context_class
!= error_mark_node
1505 && CLASS_TYPE_P (context_class
)
1506 && CLASS_TYPE_P (qualifying_scope
)
1507 && DERIVED_FROM_P (qualifying_scope
, context_class
)
1508 && BASELINK_P (decl
))
1512 /* Look for the QUALIFYING_SCOPE as a base of the CONTEXT_CLASS.
1513 Because we do not yet know which function will be chosen by
1514 overload resolution, we cannot yet check either accessibility
1515 or ambiguity -- in either case, the choice of a static member
1516 function might make the usage valid. */
1517 base
= lookup_base (context_class
, qualifying_scope
,
1518 ba_unique
| ba_quiet
, NULL
);
1521 BASELINK_ACCESS_BINFO (decl
) = base
;
1522 BASELINK_BINFO (decl
)
1523 = lookup_base (base
, BINFO_TYPE (BASELINK_BINFO (decl
)),
1524 ba_unique
| ba_quiet
,
1533 /* Walk the class hierarchy within BINFO, in a depth-first traversal.
1534 PRE_FN is called in preorder, while POST_FN is called in postorder.
1535 If PRE_FN returns DFS_SKIP_BASES, child binfos will not be
1536 walked. If PRE_FN or POST_FN returns a different non-NULL value,
1537 that value is immediately returned and the walk is terminated. One
1538 of PRE_FN and POST_FN can be NULL. At each node, PRE_FN and
1539 POST_FN are passed the binfo to examine and the caller's DATA
1540 value. All paths are walked, thus virtual and morally virtual
1541 binfos can be multiply walked. */
1544 dfs_walk_all (tree binfo
, tree (*pre_fn
) (tree
, void *),
1545 tree (*post_fn
) (tree
, void *), void *data
)
1551 /* Call the pre-order walking function. */
1554 rval
= pre_fn (binfo
, data
);
1557 if (rval
== dfs_skip_bases
)
1563 /* Find the next child binfo to walk. */
1564 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1566 rval
= dfs_walk_all (base_binfo
, pre_fn
, post_fn
, data
);
1572 /* Call the post-order walking function. */
1575 rval
= post_fn (binfo
, data
);
1576 gcc_assert (rval
!= dfs_skip_bases
);
1583 /* Worker for dfs_walk_once. This behaves as dfs_walk_all, except
1584 that binfos are walked at most once. */
1587 dfs_walk_once_r (tree binfo
, tree (*pre_fn
) (tree
, void *),
1588 tree (*post_fn
) (tree
, void *), void *data
)
1594 /* Call the pre-order walking function. */
1597 rval
= pre_fn (binfo
, data
);
1600 if (rval
== dfs_skip_bases
)
1607 /* Find the next child binfo to walk. */
1608 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1610 if (BINFO_VIRTUAL_P (base_binfo
))
1612 if (BINFO_MARKED (base_binfo
))
1614 BINFO_MARKED (base_binfo
) = 1;
1617 rval
= dfs_walk_once_r (base_binfo
, pre_fn
, post_fn
, data
);
1623 /* Call the post-order walking function. */
1626 rval
= post_fn (binfo
, data
);
1627 gcc_assert (rval
!= dfs_skip_bases
);
1634 /* Worker for dfs_walk_once. Recursively unmark the virtual base binfos of
1638 dfs_unmark_r (tree binfo
)
1643 /* Process the basetypes. */
1644 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1646 if (BINFO_VIRTUAL_P (base_binfo
))
1648 if (!BINFO_MARKED (base_binfo
))
1650 BINFO_MARKED (base_binfo
) = 0;
1652 /* Only walk, if it can contain more virtual bases. */
1653 if (CLASSTYPE_VBASECLASSES (BINFO_TYPE (base_binfo
)))
1654 dfs_unmark_r (base_binfo
);
1658 /* Like dfs_walk_all, except that binfos are not multiply walked. For
1659 non-diamond shaped hierarchies this is the same as dfs_walk_all.
1660 For diamond shaped hierarchies we must mark the virtual bases, to
1661 avoid multiple walks. */
1664 dfs_walk_once (tree binfo
, tree (*pre_fn
) (tree
, void *),
1665 tree (*post_fn
) (tree
, void *), void *data
)
1667 static int active
= 0; /* We must not be called recursively. */
1670 gcc_assert (pre_fn
|| post_fn
);
1671 gcc_assert (!active
);
1674 if (!CLASSTYPE_DIAMOND_SHAPED_P (BINFO_TYPE (binfo
)))
1675 /* We are not diamond shaped, and therefore cannot encounter the
1676 same binfo twice. */
1677 rval
= dfs_walk_all (binfo
, pre_fn
, post_fn
, data
);
1680 rval
= dfs_walk_once_r (binfo
, pre_fn
, post_fn
, data
);
1681 if (!BINFO_INHERITANCE_CHAIN (binfo
))
1683 /* We are at the top of the hierarchy, and can use the
1684 CLASSTYPE_VBASECLASSES list for unmarking the virtual
1686 VEC(tree
,gc
) *vbases
;
1690 for (vbases
= CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo
)), ix
= 0;
1691 VEC_iterate (tree
, vbases
, ix
, base_binfo
); ix
++)
1692 BINFO_MARKED (base_binfo
) = 0;
1695 dfs_unmark_r (binfo
);
1703 /* Worker function for dfs_walk_once_accessible. Behaves like
1704 dfs_walk_once_r, except (a) FRIENDS_P is true if special
1705 access given by the current context should be considered, (b) ONCE
1706 indicates whether bases should be marked during traversal. */
1709 dfs_walk_once_accessible_r (tree binfo
, bool friends_p
, bool once
,
1710 tree (*pre_fn
) (tree
, void *),
1711 tree (*post_fn
) (tree
, void *), void *data
)
1713 tree rval
= NULL_TREE
;
1717 /* Call the pre-order walking function. */
1720 rval
= pre_fn (binfo
, data
);
1723 if (rval
== dfs_skip_bases
)
1730 /* Find the next child binfo to walk. */
1731 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1733 bool mark
= once
&& BINFO_VIRTUAL_P (base_binfo
);
1735 if (mark
&& BINFO_MARKED (base_binfo
))
1738 /* If the base is inherited via private or protected
1739 inheritance, then we can't see it, unless we are a friend of
1740 the current binfo. */
1741 if (BINFO_BASE_ACCESS (binfo
, ix
) != access_public_node
)
1746 scope
= current_scope ();
1748 || TREE_CODE (scope
) == NAMESPACE_DECL
1749 || !is_friend (BINFO_TYPE (binfo
), scope
))
1754 BINFO_MARKED (base_binfo
) = 1;
1756 rval
= dfs_walk_once_accessible_r (base_binfo
, friends_p
, once
,
1757 pre_fn
, post_fn
, data
);
1763 /* Call the post-order walking function. */
1766 rval
= post_fn (binfo
, data
);
1767 gcc_assert (rval
!= dfs_skip_bases
);
1774 /* Like dfs_walk_once except that only accessible bases are walked.
1775 FRIENDS_P indicates whether friendship of the local context
1776 should be considered when determining accessibility. */
1779 dfs_walk_once_accessible (tree binfo
, bool friends_p
,
1780 tree (*pre_fn
) (tree
, void *),
1781 tree (*post_fn
) (tree
, void *), void *data
)
1783 bool diamond_shaped
= CLASSTYPE_DIAMOND_SHAPED_P (BINFO_TYPE (binfo
));
1784 tree rval
= dfs_walk_once_accessible_r (binfo
, friends_p
, diamond_shaped
,
1785 pre_fn
, post_fn
, data
);
1789 if (!BINFO_INHERITANCE_CHAIN (binfo
))
1791 /* We are at the top of the hierarchy, and can use the
1792 CLASSTYPE_VBASECLASSES list for unmarking the virtual
1794 VEC(tree
,gc
) *vbases
;
1798 for (vbases
= CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo
)), ix
= 0;
1799 VEC_iterate (tree
, vbases
, ix
, base_binfo
); ix
++)
1800 BINFO_MARKED (base_binfo
) = 0;
1803 dfs_unmark_r (binfo
);
1808 /* Check that virtual overrider OVERRIDER is acceptable for base function
1809 BASEFN. Issue diagnostic, and return zero, if unacceptable. */
1812 check_final_overrider (tree overrider
, tree basefn
)
1814 tree over_type
= TREE_TYPE (overrider
);
1815 tree base_type
= TREE_TYPE (basefn
);
1816 tree over_return
= TREE_TYPE (over_type
);
1817 tree base_return
= TREE_TYPE (base_type
);
1818 tree over_throw
= TYPE_RAISES_EXCEPTIONS (over_type
);
1819 tree base_throw
= TYPE_RAISES_EXCEPTIONS (base_type
);
1822 if (DECL_INVALID_OVERRIDER_P (overrider
))
1825 if (same_type_p (base_return
, over_return
))
1827 else if ((CLASS_TYPE_P (over_return
) && CLASS_TYPE_P (base_return
))
1828 || (TREE_CODE (base_return
) == TREE_CODE (over_return
)
1829 && POINTER_TYPE_P (base_return
)))
1831 /* Potentially covariant. */
1832 unsigned base_quals
, over_quals
;
1834 fail
= !POINTER_TYPE_P (base_return
);
1837 fail
= cp_type_quals (base_return
) != cp_type_quals (over_return
);
1839 base_return
= TREE_TYPE (base_return
);
1840 over_return
= TREE_TYPE (over_return
);
1842 base_quals
= cp_type_quals (base_return
);
1843 over_quals
= cp_type_quals (over_return
);
1845 if ((base_quals
& over_quals
) != over_quals
)
1848 if (CLASS_TYPE_P (base_return
) && CLASS_TYPE_P (over_return
))
1850 tree binfo
= lookup_base (over_return
, base_return
,
1851 ba_check
| ba_quiet
, NULL
);
1857 && can_convert (TREE_TYPE (base_type
), TREE_TYPE (over_type
)))
1858 /* GNU extension, allow trivial pointer conversions such as
1859 converting to void *, or qualification conversion. */
1861 /* can_convert will permit user defined conversion from a
1862 (reference to) class type. We must reject them. */
1863 over_return
= non_reference (TREE_TYPE (over_type
));
1864 if (CLASS_TYPE_P (over_return
))
1868 warning (0, "deprecated covariant return type for %q+#D",
1870 warning (0, " overriding %q+#D", basefn
);
1884 error ("invalid covariant return type for %q+#D", overrider
);
1885 error (" overriding %q+#D", basefn
);
1889 error ("conflicting return type specified for %q+#D", overrider
);
1890 error (" overriding %q+#D", basefn
);
1892 DECL_INVALID_OVERRIDER_P (overrider
) = 1;
1896 /* Check throw specifier is at least as strict. */
1897 if (!comp_except_specs (base_throw
, over_throw
, 0))
1899 error ("looser throw specifier for %q+#F", overrider
);
1900 error (" overriding %q+#F", basefn
);
1901 DECL_INVALID_OVERRIDER_P (overrider
) = 1;
1905 /* Check for conflicting type attributes. */
1906 if (!targetm
.comp_type_attributes (over_type
, base_type
))
1908 error ("conflicting type attributes specified for %q+#D", overrider
);
1909 error (" overriding %q+#D", basefn
);
1910 DECL_INVALID_OVERRIDER_P (overrider
) = 1;
1917 /* Given a class TYPE, and a function decl FNDECL, look for
1918 virtual functions in TYPE's hierarchy which FNDECL overrides.
1919 We do not look in TYPE itself, only its bases.
1921 Returns nonzero, if we find any. Set FNDECL's DECL_VIRTUAL_P, if we
1922 find that it overrides anything.
1924 We check that every function which is overridden, is correctly
1928 look_for_overrides (tree type
, tree fndecl
)
1930 tree binfo
= TYPE_BINFO (type
);
1935 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1937 tree basetype
= BINFO_TYPE (base_binfo
);
1939 if (TYPE_POLYMORPHIC_P (basetype
))
1940 found
+= look_for_overrides_r (basetype
, fndecl
);
1945 /* Look in TYPE for virtual functions with the same signature as
1949 look_for_overrides_here (tree type
, tree fndecl
)
1953 /* If there are no methods in TYPE (meaning that only implicitly
1954 declared methods will ever be provided for TYPE), then there are
1955 no virtual functions. */
1956 if (!CLASSTYPE_METHOD_VEC (type
))
1959 if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fndecl
))
1960 ix
= CLASSTYPE_DESTRUCTOR_SLOT
;
1962 ix
= lookup_fnfields_1 (type
, DECL_NAME (fndecl
));
1965 tree fns
= VEC_index (tree
, CLASSTYPE_METHOD_VEC (type
), ix
);
1967 for (; fns
; fns
= OVL_NEXT (fns
))
1969 tree fn
= OVL_CURRENT (fns
);
1971 if (!DECL_VIRTUAL_P (fn
))
1972 /* Not a virtual. */;
1973 else if (DECL_CONTEXT (fn
) != type
)
1974 /* Introduced with a using declaration. */;
1975 else if (DECL_STATIC_FUNCTION_P (fndecl
))
1977 tree btypes
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
1978 tree dtypes
= TYPE_ARG_TYPES (TREE_TYPE (fndecl
));
1979 if (compparms (TREE_CHAIN (btypes
), dtypes
))
1982 else if (same_signature_p (fndecl
, fn
))
1989 /* Look in TYPE for virtual functions overridden by FNDECL. Check both
1990 TYPE itself and its bases. */
1993 look_for_overrides_r (tree type
, tree fndecl
)
1995 tree fn
= look_for_overrides_here (type
, fndecl
);
1998 if (DECL_STATIC_FUNCTION_P (fndecl
))
2000 /* A static member function cannot match an inherited
2001 virtual member function. */
2002 error ("%q+#D cannot be declared", fndecl
);
2003 error (" since %q+#D declared in base class", fn
);
2007 /* It's definitely virtual, even if not explicitly set. */
2008 DECL_VIRTUAL_P (fndecl
) = 1;
2009 check_final_overrider (fndecl
, fn
);
2014 /* We failed to find one declared in this class. Look in its bases. */
2015 return look_for_overrides (type
, fndecl
);
2018 /* Called via dfs_walk from dfs_get_pure_virtuals. */
2021 dfs_get_pure_virtuals (tree binfo
, void *data
)
2023 tree type
= (tree
) data
;
2025 /* We're not interested in primary base classes; the derived class
2026 of which they are a primary base will contain the information we
2028 if (!BINFO_PRIMARY_P (binfo
))
2032 for (virtuals
= BINFO_VIRTUALS (binfo
);
2034 virtuals
= TREE_CHAIN (virtuals
))
2035 if (DECL_PURE_VIRTUAL_P (BV_FN (virtuals
)))
2036 VEC_safe_push (tree
, gc
, CLASSTYPE_PURE_VIRTUALS (type
),
2043 /* Set CLASSTYPE_PURE_VIRTUALS for TYPE. */
2046 get_pure_virtuals (tree type
)
2048 /* Clear the CLASSTYPE_PURE_VIRTUALS list; whatever is already there
2049 is going to be overridden. */
2050 CLASSTYPE_PURE_VIRTUALS (type
) = NULL
;
2051 /* Now, run through all the bases which are not primary bases, and
2052 collect the pure virtual functions. We look at the vtable in
2053 each class to determine what pure virtual functions are present.
2054 (A primary base is not interesting because the derived class of
2055 which it is a primary base will contain vtable entries for the
2056 pure virtuals in the base class. */
2057 dfs_walk_once (TYPE_BINFO (type
), NULL
, dfs_get_pure_virtuals
, type
);
2060 /* Debug info for C++ classes can get very large; try to avoid
2061 emitting it everywhere.
2063 Note that this optimization wins even when the target supports
2064 BINCL (if only slightly), and reduces the amount of work for the
2068 maybe_suppress_debug_info (tree t
)
2070 if (write_symbols
== NO_DEBUG
)
2073 /* We might have set this earlier in cp_finish_decl. */
2074 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t
)) = 0;
2076 /* Always emit the information for each class every time. */
2077 if (flag_emit_class_debug_always
)
2080 /* If we already know how we're handling this class, handle debug info
2082 if (CLASSTYPE_INTERFACE_KNOWN (t
))
2084 if (CLASSTYPE_INTERFACE_ONLY (t
))
2085 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t
)) = 1;
2086 /* else don't set it. */
2088 /* If the class has a vtable, write out the debug info along with
2090 else if (TYPE_CONTAINS_VPTR_P (t
))
2091 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t
)) = 1;
2093 /* Otherwise, just emit the debug info normally. */
2096 /* Note that we want debugging information for a base class of a class
2097 whose vtable is being emitted. Normally, this would happen because
2098 calling the constructor for a derived class implies calling the
2099 constructors for all bases, which involve initializing the
2100 appropriate vptr with the vtable for the base class; but in the
2101 presence of optimization, this initialization may be optimized
2102 away, so we tell finish_vtable_vardecl that we want the debugging
2103 information anyway. */
2106 dfs_debug_mark (tree binfo
, void *data ATTRIBUTE_UNUSED
)
2108 tree t
= BINFO_TYPE (binfo
);
2110 if (CLASSTYPE_DEBUG_REQUESTED (t
))
2111 return dfs_skip_bases
;
2113 CLASSTYPE_DEBUG_REQUESTED (t
) = 1;
2118 /* Write out the debugging information for TYPE, whose vtable is being
2119 emitted. Also walk through our bases and note that we want to
2120 write out information for them. This avoids the problem of not
2121 writing any debug info for intermediate basetypes whose
2122 constructors, and thus the references to their vtables, and thus
2123 the vtables themselves, were optimized away. */
2126 note_debug_info_needed (tree type
)
2128 if (TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type
)))
2130 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type
)) = 0;
2131 rest_of_type_compilation (type
, toplevel_bindings_p ());
2134 dfs_walk_all (TYPE_BINFO (type
), dfs_debug_mark
, NULL
, 0);
2138 print_search_statistics (void)
2140 #ifdef GATHER_STATISTICS
2141 fprintf (stderr
, "%d fields searched in %d[%d] calls to lookup_field[_1]\n",
2142 n_fields_searched
, n_calls_lookup_field
, n_calls_lookup_field_1
);
2143 fprintf (stderr
, "%d fnfields searched in %d calls to lookup_fnfields\n",
2144 n_outer_fields_searched
, n_calls_lookup_fnfields
);
2145 fprintf (stderr
, "%d calls to get_base_type\n", n_calls_get_base_type
);
2146 #else /* GATHER_STATISTICS */
2147 fprintf (stderr
, "no search statistics\n");
2148 #endif /* GATHER_STATISTICS */
2152 reinit_search_statistics (void)
2154 #ifdef GATHER_STATISTICS
2155 n_fields_searched
= 0;
2156 n_calls_lookup_field
= 0, n_calls_lookup_field_1
= 0;
2157 n_calls_lookup_fnfields
= 0, n_calls_lookup_fnfields_1
= 0;
2158 n_calls_get_base_type
= 0;
2159 n_outer_fields_searched
= 0;
2160 n_contexts_saved
= 0;
2161 #endif /* GATHER_STATISTICS */
2164 /* Helper for lookup_conversions_r. TO_TYPE is the type converted to
2165 by a conversion op in base BINFO. VIRTUAL_DEPTH is nonzero if
2166 BINFO is morally virtual, and VIRTUALNESS is nonzero if virtual
2167 bases have been encountered already in the tree walk. PARENT_CONVS
2168 is the list of lists of conversion functions that could hide CONV
2169 and OTHER_CONVS is the list of lists of conversion functions that
2170 could hide or be hidden by CONV, should virtualness be involved in
2171 the hierarchy. Merely checking the conversion op's name is not
2172 enough because two conversion operators to the same type can have
2173 different names. Return nonzero if we are visible. */
2176 check_hidden_convs (tree binfo
, int virtual_depth
, int virtualness
,
2177 tree to_type
, tree parent_convs
, tree other_convs
)
2181 /* See if we are hidden by a parent conversion. */
2182 for (level
= parent_convs
; level
; level
= TREE_CHAIN (level
))
2183 for (probe
= TREE_VALUE (level
); probe
; probe
= TREE_CHAIN (probe
))
2184 if (same_type_p (to_type
, TREE_TYPE (probe
)))
2187 if (virtual_depth
|| virtualness
)
2189 /* In a virtual hierarchy, we could be hidden, or could hide a
2190 conversion function on the other_convs list. */
2191 for (level
= other_convs
; level
; level
= TREE_CHAIN (level
))
2197 if (!(virtual_depth
|| TREE_STATIC (level
)))
2198 /* Neither is morally virtual, so cannot hide each other. */
2201 if (!TREE_VALUE (level
))
2202 /* They evaporated away already. */
2205 they_hide_us
= (virtual_depth
2206 && original_binfo (binfo
, TREE_PURPOSE (level
)));
2207 we_hide_them
= (!they_hide_us
&& TREE_STATIC (level
)
2208 && original_binfo (TREE_PURPOSE (level
), binfo
));
2210 if (!(we_hide_them
|| they_hide_us
))
2211 /* Neither is within the other, so no hiding can occur. */
2214 for (prev
= &TREE_VALUE (level
), other
= *prev
; other
;)
2216 if (same_type_p (to_type
, TREE_TYPE (other
)))
2219 /* We are hidden. */
2224 /* We hide the other one. */
2225 other
= TREE_CHAIN (other
);
2230 prev
= &TREE_CHAIN (other
);
2238 /* Helper for lookup_conversions_r. PARENT_CONVS is a list of lists
2239 of conversion functions, the first slot will be for the current
2240 binfo, if MY_CONVS is non-NULL. CHILD_CONVS is the list of lists
2241 of conversion functions from children of the current binfo,
2242 concatenated with conversions from elsewhere in the hierarchy --
2243 that list begins with OTHER_CONVS. Return a single list of lists
2244 containing only conversions from the current binfo and its
2248 split_conversions (tree my_convs
, tree parent_convs
,
2249 tree child_convs
, tree other_convs
)
2254 /* Remove the original other_convs portion from child_convs. */
2255 for (prev
= NULL
, t
= child_convs
;
2256 t
!= other_convs
; prev
= t
, t
= TREE_CHAIN (t
))
2260 TREE_CHAIN (prev
) = NULL_TREE
;
2262 child_convs
= NULL_TREE
;
2264 /* Attach the child convs to any we had at this level. */
2267 my_convs
= parent_convs
;
2268 TREE_CHAIN (my_convs
) = child_convs
;
2271 my_convs
= child_convs
;
2276 /* Worker for lookup_conversions. Lookup conversion functions in
2277 BINFO and its children. VIRTUAL_DEPTH is nonzero, if BINFO is in
2278 a morally virtual base, and VIRTUALNESS is nonzero, if we've
2279 encountered virtual bases already in the tree walk. PARENT_CONVS &
2280 PARENT_TPL_CONVS are lists of list of conversions within parent
2281 binfos. OTHER_CONVS and OTHER_TPL_CONVS are conversions found
2282 elsewhere in the tree. Return the conversions found within this
2283 portion of the graph in CONVS and TPL_CONVS. Return nonzero is we
2284 encountered virtualness. We keep template and non-template
2285 conversions separate, to avoid unnecessary type comparisons.
2287 The located conversion functions are held in lists of lists. The
2288 TREE_VALUE of the outer list is the list of conversion functions
2289 found in a particular binfo. The TREE_PURPOSE of both the outer
2290 and inner lists is the binfo at which those conversions were
2291 found. TREE_STATIC is set for those lists within of morally
2292 virtual binfos. The TREE_VALUE of the inner list is the conversion
2293 function or overload itself. The TREE_TYPE of each inner list node
2294 is the converted-to type. */
2297 lookup_conversions_r (tree binfo
,
2298 int virtual_depth
, int virtualness
,
2299 tree parent_convs
, tree parent_tpl_convs
,
2300 tree other_convs
, tree other_tpl_convs
,
2301 tree
*convs
, tree
*tpl_convs
)
2303 int my_virtualness
= 0;
2304 tree my_convs
= NULL_TREE
;
2305 tree my_tpl_convs
= NULL_TREE
;
2306 tree child_convs
= NULL_TREE
;
2307 tree child_tpl_convs
= NULL_TREE
;
2310 VEC(tree
,gc
) *method_vec
= CLASSTYPE_METHOD_VEC (BINFO_TYPE (binfo
));
2313 /* If we have no conversion operators, then don't look. */
2314 if (!TYPE_HAS_CONVERSION (BINFO_TYPE (binfo
)))
2316 *convs
= *tpl_convs
= NULL_TREE
;
2321 if (BINFO_VIRTUAL_P (binfo
))
2324 /* First, locate the unhidden ones at this level. */
2325 for (i
= CLASSTYPE_FIRST_CONVERSION_SLOT
;
2326 VEC_iterate (tree
, method_vec
, i
, conv
);
2329 tree cur
= OVL_CURRENT (conv
);
2331 if (!DECL_CONV_FN_P (cur
))
2334 if (TREE_CODE (cur
) == TEMPLATE_DECL
)
2336 /* Only template conversions can be overloaded, and we must
2337 flatten them out and check each one individually. */
2340 for (tpls
= conv
; tpls
; tpls
= OVL_NEXT (tpls
))
2342 tree tpl
= OVL_CURRENT (tpls
);
2343 tree type
= DECL_CONV_FN_TYPE (tpl
);
2345 if (check_hidden_convs (binfo
, virtual_depth
, virtualness
,
2346 type
, parent_tpl_convs
, other_tpl_convs
))
2348 my_tpl_convs
= tree_cons (binfo
, tpl
, my_tpl_convs
);
2349 TREE_TYPE (my_tpl_convs
) = type
;
2352 TREE_STATIC (my_tpl_convs
) = 1;
2360 tree name
= DECL_NAME (cur
);
2362 if (!IDENTIFIER_MARKED (name
))
2364 tree type
= DECL_CONV_FN_TYPE (cur
);
2366 if (check_hidden_convs (binfo
, virtual_depth
, virtualness
,
2367 type
, parent_convs
, other_convs
))
2369 my_convs
= tree_cons (binfo
, conv
, my_convs
);
2370 TREE_TYPE (my_convs
) = type
;
2373 TREE_STATIC (my_convs
) = 1;
2376 IDENTIFIER_MARKED (name
) = 1;
2384 parent_convs
= tree_cons (binfo
, my_convs
, parent_convs
);
2386 TREE_STATIC (parent_convs
) = 1;
2391 parent_tpl_convs
= tree_cons (binfo
, my_tpl_convs
, parent_tpl_convs
);
2393 TREE_STATIC (parent_tpl_convs
) = 1;
2396 child_convs
= other_convs
;
2397 child_tpl_convs
= other_tpl_convs
;
2399 /* Now iterate over each base, looking for more conversions. */
2400 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
2402 tree base_convs
, base_tpl_convs
;
2403 unsigned base_virtualness
;
2405 base_virtualness
= lookup_conversions_r (base_binfo
,
2406 virtual_depth
, virtualness
,
2407 parent_convs
, parent_tpl_convs
,
2408 child_convs
, child_tpl_convs
,
2409 &base_convs
, &base_tpl_convs
);
2410 if (base_virtualness
)
2411 my_virtualness
= virtualness
= 1;
2412 child_convs
= chainon (base_convs
, child_convs
);
2413 child_tpl_convs
= chainon (base_tpl_convs
, child_tpl_convs
);
2416 /* Unmark the conversions found at this level */
2417 for (conv
= my_convs
; conv
; conv
= TREE_CHAIN (conv
))
2418 IDENTIFIER_MARKED (DECL_NAME (OVL_CURRENT (TREE_VALUE (conv
)))) = 0;
2420 *convs
= split_conversions (my_convs
, parent_convs
,
2421 child_convs
, other_convs
);
2422 *tpl_convs
= split_conversions (my_tpl_convs
, parent_tpl_convs
,
2423 child_tpl_convs
, other_tpl_convs
);
2425 return my_virtualness
;
2428 /* Return a TREE_LIST containing all the non-hidden user-defined
2429 conversion functions for TYPE (and its base-classes). The
2430 TREE_VALUE of each node is the FUNCTION_DECL of the conversion
2431 function. The TREE_PURPOSE is the BINFO from which the conversion
2432 functions in this node were selected. This function is effectively
2433 performing a set of member lookups as lookup_fnfield does, but
2434 using the type being converted to as the unique key, rather than the
2438 lookup_conversions (tree type
)
2440 tree convs
, tpl_convs
;
2441 tree list
= NULL_TREE
;
2443 complete_type (type
);
2444 if (!TYPE_BINFO (type
))
2447 lookup_conversions_r (TYPE_BINFO (type
), 0, 0,
2448 NULL_TREE
, NULL_TREE
, NULL_TREE
, NULL_TREE
,
2449 &convs
, &tpl_convs
);
2451 /* Flatten the list-of-lists */
2452 for (; convs
; convs
= TREE_CHAIN (convs
))
2456 for (probe
= TREE_VALUE (convs
); probe
; probe
= next
)
2458 next
= TREE_CHAIN (probe
);
2460 TREE_CHAIN (probe
) = list
;
2465 for (; tpl_convs
; tpl_convs
= TREE_CHAIN (tpl_convs
))
2469 for (probe
= TREE_VALUE (tpl_convs
); probe
; probe
= next
)
2471 next
= TREE_CHAIN (probe
);
2473 TREE_CHAIN (probe
) = list
;
2481 /* Returns the binfo of the first direct or indirect virtual base derived
2482 from BINFO, or NULL if binfo is not via virtual. */
2485 binfo_from_vbase (tree binfo
)
2487 for (; binfo
; binfo
= BINFO_INHERITANCE_CHAIN (binfo
))
2489 if (BINFO_VIRTUAL_P (binfo
))
2495 /* Returns the binfo of the first direct or indirect virtual base derived
2496 from BINFO up to the TREE_TYPE, LIMIT, or NULL if binfo is not
2500 binfo_via_virtual (tree binfo
, tree limit
)
2502 if (limit
&& !CLASSTYPE_VBASECLASSES (limit
))
2503 /* LIMIT has no virtual bases, so BINFO cannot be via one. */
2506 for (; binfo
&& !SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), limit
);
2507 binfo
= BINFO_INHERITANCE_CHAIN (binfo
))
2509 if (BINFO_VIRTUAL_P (binfo
))
2515 /* BINFO is a base binfo in the complete type BINFO_TYPE (HERE).
2516 Find the equivalent binfo within whatever graph HERE is located.
2517 This is the inverse of original_binfo. */
2520 copied_binfo (tree binfo
, tree here
)
2522 tree result
= NULL_TREE
;
2524 if (BINFO_VIRTUAL_P (binfo
))
2528 for (t
= here
; BINFO_INHERITANCE_CHAIN (t
);
2529 t
= BINFO_INHERITANCE_CHAIN (t
))
2532 result
= binfo_for_vbase (BINFO_TYPE (binfo
), BINFO_TYPE (t
));
2534 else if (BINFO_INHERITANCE_CHAIN (binfo
))
2540 cbinfo
= copied_binfo (BINFO_INHERITANCE_CHAIN (binfo
), here
);
2541 for (ix
= 0; BINFO_BASE_ITERATE (cbinfo
, ix
, base_binfo
); ix
++)
2542 if (SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo
), BINFO_TYPE (binfo
)))
2544 result
= base_binfo
;
2550 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (here
), BINFO_TYPE (binfo
)));
2554 gcc_assert (result
);
2559 binfo_for_vbase (tree base
, tree t
)
2563 VEC(tree
,gc
) *vbases
;
2565 for (vbases
= CLASSTYPE_VBASECLASSES (t
), ix
= 0;
2566 VEC_iterate (tree
, vbases
, ix
, binfo
); ix
++)
2567 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), base
))
2572 /* BINFO is some base binfo of HERE, within some other
2573 hierarchy. Return the equivalent binfo, but in the hierarchy
2574 dominated by HERE. This is the inverse of copied_binfo. If BINFO
2575 is not a base binfo of HERE, returns NULL_TREE. */
2578 original_binfo (tree binfo
, tree here
)
2582 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), BINFO_TYPE (here
)))
2584 else if (BINFO_VIRTUAL_P (binfo
))
2585 result
= (CLASSTYPE_VBASECLASSES (BINFO_TYPE (here
))
2586 ? binfo_for_vbase (BINFO_TYPE (binfo
), BINFO_TYPE (here
))
2588 else if (BINFO_INHERITANCE_CHAIN (binfo
))
2592 base_binfos
= original_binfo (BINFO_INHERITANCE_CHAIN (binfo
), here
);
2598 for (ix
= 0; (base_binfo
= BINFO_BASE_BINFO (base_binfos
, ix
)); ix
++)
2599 if (SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo
),
2600 BINFO_TYPE (binfo
)))
2602 result
= base_binfo
;