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
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"
39 static int is_subobject_of_p (tree
, tree
);
40 static tree
dfs_lookup_base (tree
, void *);
41 static tree
dfs_dcast_hint_pre (tree
, void *);
42 static tree
dfs_dcast_hint_post (tree
, void *);
43 static tree
dfs_debug_mark (tree
, void *);
44 static tree
dfs_walk_once_r (tree
, tree (*pre_fn
) (tree
, void *),
45 tree (*post_fn
) (tree
, void *), void *data
);
46 static void dfs_unmark_r (tree
);
47 static int check_hidden_convs (tree
, int, int, tree
, tree
, tree
);
48 static tree
split_conversions (tree
, tree
, tree
, tree
);
49 static int lookup_conversions_r (tree
, int, int,
50 tree
, tree
, tree
, tree
, tree
*, tree
*);
51 static int look_for_overrides_r (tree
, tree
);
52 static tree
lookup_field_r (tree
, void *);
53 static tree
dfs_accessible_post (tree
, void *);
54 static tree
dfs_walk_once_accessible_r (tree
, bool, bool,
55 tree (*pre_fn
) (tree
, void *),
56 tree (*post_fn
) (tree
, void *),
58 static tree
dfs_walk_once_accessible (tree
, bool,
59 tree (*pre_fn
) (tree
, void *),
60 tree (*post_fn
) (tree
, void *),
62 static tree
dfs_access_in_type (tree
, void *);
63 static access_kind
access_in_type (tree
, tree
);
64 static int protected_accessible_p (tree
, tree
, tree
);
65 static int friend_accessible_p (tree
, tree
, tree
);
66 static int template_self_reference_p (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
= complete_type (TYPE_MAIN_VARIANT (base
));
221 struct lookup_base_data_s data
;
225 data
.binfo
= NULL_TREE
;
226 data
.ambiguous
= data
.via_virtual
= false;
227 data
.repeated_base
= CLASSTYPE_REPEATED_BASE_P (t
);
228 data
.want_any
= access
== ba_any
;
230 dfs_walk_once (t_binfo
, dfs_lookup_base
, NULL
, &data
);
234 bk
= data
.ambiguous
? bk_ambig
: bk_not_base
;
235 else if (binfo
== t_binfo
)
237 else if (data
.via_virtual
)
248 /* Check that the base is unambiguous and accessible. */
249 if (access
!= ba_any
)
256 if (!(access
& ba_quiet
))
258 error ("%qT is an ambiguous base of %qT", base
, t
);
259 binfo
= error_mark_node
;
264 if ((access
& ba_check_bit
)
265 /* If BASE is incomplete, then BASE and TYPE are probably
266 the same, in which case BASE is accessible. If they
267 are not the same, then TYPE is invalid. In that case,
268 there's no need to issue another error here, and
269 there's no implicit typedef to use in the code that
270 follows, so we skip the check. */
271 && COMPLETE_TYPE_P (base
)
272 && !accessible_base_p (t
, base
, !(access
& ba_ignore_scope
)))
274 if (!(access
& ba_quiet
))
276 error ("%qT is an inaccessible base of %qT", base
, t
);
277 binfo
= error_mark_node
;
281 bk
= bk_inaccessible
;
292 /* Data for dcast_base_hint walker. */
296 tree subtype
; /* The base type we're looking for. */
297 int virt_depth
; /* Number of virtual bases encountered from most
299 tree offset
; /* Best hint offset discovered so far. */
300 bool repeated_base
; /* Whether there are repeated bases in the
304 /* Worker for dcast_base_hint. Search for the base type being cast
308 dfs_dcast_hint_pre (tree binfo
, void *data_
)
310 struct dcast_data_s
*data
= (struct dcast_data_s
*) data_
;
312 if (BINFO_VIRTUAL_P (binfo
))
315 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), data
->subtype
))
317 if (data
->virt_depth
)
319 data
->offset
= ssize_int (-1);
323 data
->offset
= ssize_int (-3);
325 data
->offset
= BINFO_OFFSET (binfo
);
327 return data
->repeated_base
? dfs_skip_bases
: data
->offset
;
333 /* Worker for dcast_base_hint. Track the virtual depth. */
336 dfs_dcast_hint_post (tree binfo
, void *data_
)
338 struct dcast_data_s
*data
= (struct dcast_data_s
*) data_
;
340 if (BINFO_VIRTUAL_P (binfo
))
346 /* The dynamic cast runtime needs a hint about how the static SUBTYPE type
347 started from is related to the required TARGET type, in order to optimize
348 the inheritance graph search. This information is independent of the
349 current context, and ignores private paths, hence get_base_distance is
350 inappropriate. Return a TREE specifying the base offset, BOFF.
351 BOFF >= 0, there is only one public non-virtual SUBTYPE base at offset BOFF,
352 and there are no public virtual SUBTYPE bases.
353 BOFF == -1, SUBTYPE occurs as multiple public virtual or non-virtual bases.
354 BOFF == -2, SUBTYPE is not a public base.
355 BOFF == -3, SUBTYPE occurs as multiple public non-virtual bases. */
358 dcast_base_hint (tree subtype
, tree target
)
360 struct dcast_data_s data
;
362 data
.subtype
= subtype
;
364 data
.offset
= NULL_TREE
;
365 data
.repeated_base
= CLASSTYPE_REPEATED_BASE_P (target
);
367 dfs_walk_once_accessible (TYPE_BINFO (target
), /*friends=*/false,
368 dfs_dcast_hint_pre
, dfs_dcast_hint_post
, &data
);
369 return data
.offset
? data
.offset
: ssize_int (-2);
372 /* Search for a member with name NAME in a multiple inheritance
373 lattice specified by TYPE. If it does not exist, return NULL_TREE.
374 If the member is ambiguously referenced, return `error_mark_node'.
375 Otherwise, return a DECL with the indicated name. If WANT_TYPE is
376 true, type declarations are preferred. */
378 /* Do a 1-level search for NAME as a member of TYPE. The caller must
379 figure out whether it can access this field. (Since it is only one
380 level, this is reasonable.) */
383 lookup_field_1 (tree type
, tree name
, bool want_type
)
387 if (TREE_CODE (type
) == TEMPLATE_TYPE_PARM
388 || TREE_CODE (type
) == BOUND_TEMPLATE_TEMPLATE_PARM
389 || TREE_CODE (type
) == TYPENAME_TYPE
)
390 /* The TYPE_FIELDS of a TEMPLATE_TYPE_PARM and
391 BOUND_TEMPLATE_TEMPLATE_PARM are not fields at all;
392 instead TYPE_FIELDS is the TEMPLATE_PARM_INDEX. (Miraculously,
393 the code often worked even when we treated the index as a list
395 The TYPE_FIELDS of TYPENAME_TYPE is its TYPENAME_TYPE_FULLNAME. */
399 && DECL_LANG_SPECIFIC (TYPE_NAME (type
))
400 && DECL_SORTED_FIELDS (TYPE_NAME (type
)))
402 tree
*fields
= &DECL_SORTED_FIELDS (TYPE_NAME (type
))->elts
[0];
403 int lo
= 0, hi
= DECL_SORTED_FIELDS (TYPE_NAME (type
))->len
;
410 #ifdef GATHER_STATISTICS
412 #endif /* GATHER_STATISTICS */
414 if (DECL_NAME (fields
[i
]) > name
)
416 else if (DECL_NAME (fields
[i
]) < name
)
422 /* We might have a nested class and a field with the
423 same name; we sorted them appropriately via
424 field_decl_cmp, so just look for the first or last
425 field with this name. */
430 while (i
>= lo
&& DECL_NAME (fields
[i
]) == name
);
431 if (TREE_CODE (field
) != TYPE_DECL
432 && !DECL_CLASS_TEMPLATE_P (field
))
439 while (i
< hi
&& DECL_NAME (fields
[i
]) == name
);
447 field
= TYPE_FIELDS (type
);
449 #ifdef GATHER_STATISTICS
450 n_calls_lookup_field_1
++;
451 #endif /* GATHER_STATISTICS */
452 for (field
= TYPE_FIELDS (type
); field
; field
= TREE_CHAIN (field
))
454 #ifdef GATHER_STATISTICS
456 #endif /* GATHER_STATISTICS */
457 gcc_assert (DECL_P (field
));
458 if (DECL_NAME (field
) == NULL_TREE
459 && ANON_AGGR_TYPE_P (TREE_TYPE (field
)))
461 tree temp
= lookup_field_1 (TREE_TYPE (field
), name
, want_type
);
465 if (TREE_CODE (field
) == USING_DECL
)
467 /* We generally treat class-scope using-declarations as
468 ARM-style access specifications, because support for the
469 ISO semantics has not been implemented. So, in general,
470 there's no reason to return a USING_DECL, and the rest of
471 the compiler cannot handle that. Once the class is
472 defined, USING_DECLs are purged from TYPE_FIELDS; see
473 handle_using_decl. However, we make special efforts to
474 make using-declarations in class templates and class
475 template partial specializations work correctly. */
476 if (!DECL_DEPENDENT_P (field
))
480 if (DECL_NAME (field
) == name
482 || TREE_CODE (field
) == TYPE_DECL
483 || DECL_CLASS_TEMPLATE_P (field
)))
487 if (name
== vptr_identifier
)
489 /* Give the user what s/he thinks s/he wants. */
490 if (TYPE_POLYMORPHIC_P (type
))
491 return TYPE_VFIELD (type
);
496 /* Return the FUNCTION_DECL, RECORD_TYPE, UNION_TYPE, or
497 NAMESPACE_DECL corresponding to the innermost non-block scope. */
502 /* There are a number of cases we need to be aware of here:
503 current_class_type current_function_decl
510 Those last two make life interesting. If we're in a function which is
511 itself inside a class, we need decls to go into the fn's decls (our
512 second case below). But if we're in a class and the class itself is
513 inside a function, we need decls to go into the decls for the class. To
514 achieve this last goal, we must see if, when both current_class_ptr and
515 current_function_decl are set, the class was declared inside that
516 function. If so, we know to put the decls into the class's scope. */
517 if (current_function_decl
&& current_class_type
518 && ((DECL_FUNCTION_MEMBER_P (current_function_decl
)
519 && same_type_p (DECL_CONTEXT (current_function_decl
),
521 || (DECL_FRIEND_CONTEXT (current_function_decl
)
522 && same_type_p (DECL_FRIEND_CONTEXT (current_function_decl
),
523 current_class_type
))))
524 return current_function_decl
;
525 if (current_class_type
)
526 return current_class_type
;
527 if (current_function_decl
)
528 return current_function_decl
;
529 return current_namespace
;
532 /* Returns nonzero if we are currently in a function scope. Note
533 that this function returns zero if we are within a local class, but
534 not within a member function body of the local class. */
537 at_function_scope_p (void)
539 tree cs
= current_scope ();
540 return cs
&& TREE_CODE (cs
) == FUNCTION_DECL
;
543 /* Returns true if the innermost active scope is a class scope. */
546 at_class_scope_p (void)
548 tree cs
= current_scope ();
549 return cs
&& TYPE_P (cs
);
552 /* Returns true if the innermost active scope is a namespace scope. */
555 at_namespace_scope_p (void)
557 tree cs
= current_scope ();
558 return cs
&& TREE_CODE (cs
) == NAMESPACE_DECL
;
561 /* Return the scope of DECL, as appropriate when doing name-lookup. */
564 context_for_name_lookup (tree decl
)
568 For the purposes of name lookup, after the anonymous union
569 definition, the members of the anonymous union are considered to
570 have been defined in the scope in which the anonymous union is
572 tree context
= DECL_CONTEXT (decl
);
574 while (context
&& TYPE_P (context
) && ANON_AGGR_TYPE_P (context
))
575 context
= TYPE_CONTEXT (context
);
577 context
= global_namespace
;
582 /* The accessibility routines use BINFO_ACCESS for scratch space
583 during the computation of the accessibility of some declaration. */
585 #define BINFO_ACCESS(NODE) \
586 ((access_kind) ((TREE_PUBLIC (NODE) << 1) | TREE_PRIVATE (NODE)))
588 /* Set the access associated with NODE to ACCESS. */
590 #define SET_BINFO_ACCESS(NODE, ACCESS) \
591 ((TREE_PUBLIC (NODE) = ((ACCESS) & 2) != 0), \
592 (TREE_PRIVATE (NODE) = ((ACCESS) & 1) != 0))
594 /* Called from access_in_type via dfs_walk. Calculate the access to
595 DATA (which is really a DECL) in BINFO. */
598 dfs_access_in_type (tree binfo
, void *data
)
600 tree decl
= (tree
) data
;
601 tree type
= BINFO_TYPE (binfo
);
602 access_kind access
= ak_none
;
604 if (context_for_name_lookup (decl
) == type
)
606 /* If we have descended to the scope of DECL, just note the
607 appropriate access. */
608 if (TREE_PRIVATE (decl
))
610 else if (TREE_PROTECTED (decl
))
611 access
= ak_protected
;
617 /* First, check for an access-declaration that gives us more
618 access to the DECL. The CONST_DECL for an enumeration
619 constant will not have DECL_LANG_SPECIFIC, and thus no
621 if (DECL_LANG_SPECIFIC (decl
) && !DECL_DISCRIMINATOR_P (decl
))
623 tree decl_access
= purpose_member (type
, DECL_ACCESS (decl
));
627 decl_access
= TREE_VALUE (decl_access
);
629 if (decl_access
== access_public_node
)
631 else if (decl_access
== access_protected_node
)
632 access
= ak_protected
;
633 else if (decl_access
== access_private_node
)
644 VEC(tree
,gc
) *accesses
;
646 /* Otherwise, scan our baseclasses, and pick the most favorable
648 accesses
= BINFO_BASE_ACCESSES (binfo
);
649 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
651 tree base_access
= VEC_index (tree
, accesses
, i
);
652 access_kind base_access_now
= BINFO_ACCESS (base_binfo
);
654 if (base_access_now
== ak_none
|| base_access_now
== ak_private
)
655 /* If it was not accessible in the base, or only
656 accessible as a private member, we can't access it
658 base_access_now
= ak_none
;
659 else if (base_access
== access_protected_node
)
660 /* Public and protected members in the base become
662 base_access_now
= ak_protected
;
663 else if (base_access
== access_private_node
)
664 /* Public and protected members in the base become
666 base_access_now
= ak_private
;
668 /* See if the new access, via this base, gives more
669 access than our previous best access. */
670 if (base_access_now
!= ak_none
671 && (access
== ak_none
|| base_access_now
< access
))
673 access
= base_access_now
;
675 /* If the new access is public, we can't do better. */
676 if (access
== ak_public
)
683 /* Note the access to DECL in TYPE. */
684 SET_BINFO_ACCESS (binfo
, access
);
689 /* Return the access to DECL in TYPE. */
692 access_in_type (tree type
, tree decl
)
694 tree binfo
= TYPE_BINFO (type
);
696 /* We must take into account
700 If a name can be reached by several paths through a multiple
701 inheritance graph, the access is that of the path that gives
704 The algorithm we use is to make a post-order depth-first traversal
705 of the base-class hierarchy. As we come up the tree, we annotate
706 each node with the most lenient access. */
707 dfs_walk_once (binfo
, NULL
, dfs_access_in_type
, decl
);
709 return BINFO_ACCESS (binfo
);
712 /* Returns nonzero if it is OK to access DECL through an object
713 indicated by BINFO in the context of DERIVED. */
716 protected_accessible_p (tree decl
, tree derived
, tree binfo
)
720 /* We're checking this clause from [class.access.base]
722 m as a member of N is protected, and the reference occurs in a
723 member or friend of class N, or in a member or friend of a
724 class P derived from N, where m as a member of P is private or
727 Here DERIVED is a possible P and DECL is m. accessible_p will
728 iterate over various values of N, but the access to m in DERIVED
731 Note that I believe that the passage above is wrong, and should read
732 "...is private or protected or public"; otherwise you get bizarre results
733 whereby a public using-decl can prevent you from accessing a protected
734 member of a base. (jason 2000/02/28) */
736 /* If DERIVED isn't derived from m's class, then it can't be a P. */
737 if (!DERIVED_FROM_P (context_for_name_lookup (decl
), derived
))
740 access
= access_in_type (derived
, decl
);
742 /* If m is inaccessible in DERIVED, then it's not a P. */
743 if (access
== ak_none
)
748 When a friend or a member function of a derived class references
749 a protected nonstatic member of a base class, an access check
750 applies in addition to those described earlier in clause
751 _class.access_) Except when forming a pointer to member
752 (_expr.unary.op_), the access must be through a pointer to,
753 reference to, or object of the derived class itself (or any class
754 derived from that class) (_expr.ref_). If the access is to form
755 a pointer to member, the nested-name-specifier shall name the
756 derived class (or any class derived from that class). */
757 if (DECL_NONSTATIC_MEMBER_P (decl
))
759 /* We can tell through what the reference is occurring by
760 chasing BINFO up to the root. */
762 while (BINFO_INHERITANCE_CHAIN (t
))
763 t
= BINFO_INHERITANCE_CHAIN (t
);
765 if (!DERIVED_FROM_P (derived
, BINFO_TYPE (t
)))
772 /* Returns nonzero if SCOPE is a friend of a type which would be able
773 to access DECL through the object indicated by BINFO. */
776 friend_accessible_p (tree scope
, tree decl
, tree binfo
)
778 tree befriending_classes
;
784 if (TREE_CODE (scope
) == FUNCTION_DECL
785 || DECL_FUNCTION_TEMPLATE_P (scope
))
786 befriending_classes
= DECL_BEFRIENDING_CLASSES (scope
);
787 else if (TYPE_P (scope
))
788 befriending_classes
= CLASSTYPE_BEFRIENDING_CLASSES (scope
);
792 for (t
= befriending_classes
; t
; t
= TREE_CHAIN (t
))
793 if (protected_accessible_p (decl
, TREE_VALUE (t
), binfo
))
796 /* Nested classes have the same access as their enclosing types, as
797 per DR 45 (this is a change from the standard). */
799 for (t
= TYPE_CONTEXT (scope
); t
&& TYPE_P (t
); t
= TYPE_CONTEXT (t
))
800 if (protected_accessible_p (decl
, t
, binfo
))
803 if (TREE_CODE (scope
) == FUNCTION_DECL
804 || DECL_FUNCTION_TEMPLATE_P (scope
))
806 /* Perhaps this SCOPE is a member of a class which is a
808 if (DECL_CLASS_SCOPE_P (scope
)
809 && friend_accessible_p (DECL_CONTEXT (scope
), decl
, binfo
))
812 /* Or an instantiation of something which is a friend. */
813 if (DECL_TEMPLATE_INFO (scope
))
816 /* Increment processing_template_decl to make sure that
817 dependent_type_p works correctly. */
818 ++processing_template_decl
;
819 ret
= friend_accessible_p (DECL_TI_TEMPLATE (scope
), decl
, binfo
);
820 --processing_template_decl
;
828 /* Called via dfs_walk_once_accessible from accessible_p */
831 dfs_accessible_post (tree binfo
, void *data ATTRIBUTE_UNUSED
)
833 if (BINFO_ACCESS (binfo
) != ak_none
)
835 tree scope
= current_scope ();
836 if (scope
&& TREE_CODE (scope
) != NAMESPACE_DECL
837 && is_friend (BINFO_TYPE (binfo
), scope
))
844 /* DECL is a declaration from a base class of TYPE, which was the
845 class used to name DECL. Return nonzero if, in the current
846 context, DECL is accessible. If TYPE is actually a BINFO node,
847 then we can tell in what context the access is occurring by looking
848 at the most derived class along the path indicated by BINFO. If
849 CONSIDER_LOCAL is true, do consider special access the current
850 scope or friendship thereof we might have. */
853 accessible_p (tree type
, tree decl
, bool consider_local_p
)
859 /* Nonzero if it's OK to access DECL if it has protected
860 accessibility in TYPE. */
861 int protected_ok
= 0;
863 /* If this declaration is in a block or namespace scope, there's no
865 if (!TYPE_P (context_for_name_lookup (decl
)))
868 /* There is no need to perform access checks inside a thunk. */
869 scope
= current_scope ();
870 if (scope
&& DECL_THUNK_P (scope
))
873 /* In a template declaration, we cannot be sure whether the
874 particular specialization that is instantiated will be a friend
875 or not. Therefore, all access checks are deferred until
876 instantiation. However, PROCESSING_TEMPLATE_DECL is set in the
877 parameter list for a template (because we may see dependent types
878 in default arguments for template parameters), and access
879 checking should be performed in the outermost parameter list. */
880 if (processing_template_decl
881 && (!processing_template_parmlist
|| processing_template_decl
> 1))
887 type
= BINFO_TYPE (type
);
890 binfo
= TYPE_BINFO (type
);
892 /* [class.access.base]
894 A member m is accessible when named in class N if
896 --m as a member of N is public, or
898 --m as a member of N is private, and the reference occurs in a
899 member or friend of class N, or
901 --m as a member of N is protected, and the reference occurs in a
902 member or friend of class N, or in a member or friend of a
903 class P derived from N, where m as a member of P is private or
906 --there exists a base class B of N that is accessible at the point
907 of reference, and m is accessible when named in class B.
909 We walk the base class hierarchy, checking these conditions. */
911 if (consider_local_p
)
913 /* Figure out where the reference is occurring. Check to see if
914 DECL is private or protected in this scope, since that will
915 determine whether protected access is allowed. */
916 if (current_class_type
)
917 protected_ok
= protected_accessible_p (decl
,
918 current_class_type
, binfo
);
920 /* Now, loop through the classes of which we are a friend. */
922 protected_ok
= friend_accessible_p (scope
, decl
, binfo
);
925 /* Standardize the binfo that access_in_type will use. We don't
926 need to know what path was chosen from this point onwards. */
927 binfo
= TYPE_BINFO (type
);
929 /* Compute the accessibility of DECL in the class hierarchy
930 dominated by type. */
931 access
= access_in_type (type
, decl
);
932 if (access
== ak_public
933 || (access
== ak_protected
&& protected_ok
))
936 if (!consider_local_p
)
939 /* Walk the hierarchy again, looking for a base class that allows
941 return dfs_walk_once_accessible (binfo
, /*friends=*/true,
942 NULL
, dfs_accessible_post
, NULL
)
946 struct lookup_field_info
{
947 /* The type in which we're looking. */
949 /* The name of the field for which we're looking. */
951 /* If non-NULL, the current result of the lookup. */
953 /* The path to RVAL. */
955 /* If non-NULL, the lookup was ambiguous, and this is a list of the
958 /* If nonzero, we are looking for types, not data members. */
960 /* If something went wrong, a message indicating what. */
964 /* Within the scope of a template class, you can refer to the to the
965 current specialization with the name of the template itself. For
968 template <typename T> struct S { S* sp; }
970 Returns nonzero if DECL is such a declaration in a class TYPE. */
973 template_self_reference_p (tree type
, tree decl
)
975 return (CLASSTYPE_USE_TEMPLATE (type
)
976 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type
))
977 && TREE_CODE (decl
) == TYPE_DECL
978 && DECL_ARTIFICIAL (decl
)
979 && DECL_NAME (decl
) == constructor_name (type
));
982 /* Nonzero for a class member means that it is shared between all objects
985 [class.member.lookup]:If the resulting set of declarations are not all
986 from sub-objects of the same type, or the set has a nonstatic member
987 and includes members from distinct sub-objects, there is an ambiguity
988 and the program is ill-formed.
990 This function checks that T contains no nonstatic members. */
993 shared_member_p (tree t
)
995 if (TREE_CODE (t
) == VAR_DECL
|| TREE_CODE (t
) == TYPE_DECL \
996 || TREE_CODE (t
) == CONST_DECL
)
998 if (is_overloaded_fn (t
))
1000 for (; t
; t
= OVL_NEXT (t
))
1002 tree fn
= OVL_CURRENT (t
);
1003 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
1011 /* Routine to see if the sub-object denoted by the binfo PARENT can be
1012 found as a base class and sub-object of the object denoted by
1016 is_subobject_of_p (tree parent
, tree binfo
)
1020 for (probe
= parent
; probe
; probe
= BINFO_INHERITANCE_CHAIN (probe
))
1024 if (BINFO_VIRTUAL_P (probe
))
1025 return (binfo_for_vbase (BINFO_TYPE (probe
), BINFO_TYPE (binfo
))
1031 /* DATA is really a struct lookup_field_info. Look for a field with
1032 the name indicated there in BINFO. If this function returns a
1033 non-NULL value it is the result of the lookup. Called from
1034 lookup_field via breadth_first_search. */
1037 lookup_field_r (tree binfo
, void *data
)
1039 struct lookup_field_info
*lfi
= (struct lookup_field_info
*) data
;
1040 tree type
= BINFO_TYPE (binfo
);
1041 tree nval
= NULL_TREE
;
1043 /* If this is a dependent base, don't look in it. */
1044 if (BINFO_DEPENDENT_BASE_P (binfo
))
1047 /* If this base class is hidden by the best-known value so far, we
1048 don't need to look. */
1049 if (lfi
->rval_binfo
&& BINFO_INHERITANCE_CHAIN (binfo
) == lfi
->rval_binfo
1050 && !BINFO_VIRTUAL_P (binfo
))
1051 return dfs_skip_bases
;
1053 /* First, look for a function. There can't be a function and a data
1054 member with the same name, and if there's a function and a type
1055 with the same name, the type is hidden by the function. */
1056 if (!lfi
->want_type
)
1058 int idx
= lookup_fnfields_1 (type
, lfi
->name
);
1060 nval
= VEC_index (tree
, CLASSTYPE_METHOD_VEC (type
), idx
);
1064 /* Look for a data member or type. */
1065 nval
= lookup_field_1 (type
, lfi
->name
, lfi
->want_type
);
1067 /* If there is no declaration with the indicated name in this type,
1068 then there's nothing to do. */
1072 /* If we're looking up a type (as with an elaborated type specifier)
1073 we ignore all non-types we find. */
1074 if (lfi
->want_type
&& TREE_CODE (nval
) != TYPE_DECL
1075 && !DECL_CLASS_TEMPLATE_P (nval
))
1077 if (lfi
->name
== TYPE_IDENTIFIER (type
))
1079 /* If the aggregate has no user defined constructors, we allow
1080 it to have fields with the same name as the enclosing type.
1081 If we are looking for that name, find the corresponding
1083 for (nval
= TREE_CHAIN (nval
); nval
; nval
= TREE_CHAIN (nval
))
1084 if (DECL_NAME (nval
) == lfi
->name
1085 && TREE_CODE (nval
) == TYPE_DECL
)
1090 if (!nval
&& CLASSTYPE_NESTED_UTDS (type
) != NULL
)
1092 binding_entry e
= binding_table_find (CLASSTYPE_NESTED_UTDS (type
),
1095 nval
= TYPE_MAIN_DECL (e
->type
);
1101 /* You must name a template base class with a template-id. */
1102 if (!same_type_p (type
, lfi
->type
)
1103 && template_self_reference_p (type
, nval
))
1106 /* If the lookup already found a match, and the new value doesn't
1107 hide the old one, we might have an ambiguity. */
1109 && !is_subobject_of_p (lfi
->rval_binfo
, binfo
))
1112 if (nval
== lfi
->rval
&& shared_member_p (nval
))
1113 /* The two things are really the same. */
1115 else if (is_subobject_of_p (binfo
, lfi
->rval_binfo
))
1116 /* The previous value hides the new one. */
1120 /* We have a real ambiguity. We keep a chain of all the
1122 if (!lfi
->ambiguous
&& lfi
->rval
)
1124 /* This is the first time we noticed an ambiguity. Add
1125 what we previously thought was a reasonable candidate
1127 lfi
->ambiguous
= tree_cons (NULL_TREE
, lfi
->rval
, NULL_TREE
);
1128 TREE_TYPE (lfi
->ambiguous
) = error_mark_node
;
1131 /* Add the new value. */
1132 lfi
->ambiguous
= tree_cons (NULL_TREE
, nval
, lfi
->ambiguous
);
1133 TREE_TYPE (lfi
->ambiguous
) = error_mark_node
;
1134 lfi
->errstr
= "request for member %qD is ambiguous";
1140 lfi
->rval_binfo
= binfo
;
1144 /* Don't look for constructors or destructors in base classes. */
1145 if (IDENTIFIER_CTOR_OR_DTOR_P (lfi
->name
))
1146 return dfs_skip_bases
;
1150 /* Return a "baselink" with BASELINK_BINFO, BASELINK_ACCESS_BINFO,
1151 BASELINK_FUNCTIONS, and BASELINK_OPTYPE set to BINFO, ACCESS_BINFO,
1152 FUNCTIONS, and OPTYPE respectively. */
1155 build_baselink (tree binfo
, tree access_binfo
, tree functions
, tree optype
)
1159 gcc_assert (TREE_CODE (functions
) == FUNCTION_DECL
1160 || TREE_CODE (functions
) == TEMPLATE_DECL
1161 || TREE_CODE (functions
) == TEMPLATE_ID_EXPR
1162 || TREE_CODE (functions
) == OVERLOAD
);
1163 gcc_assert (!optype
|| TYPE_P (optype
));
1164 gcc_assert (TREE_TYPE (functions
));
1166 baselink
= make_node (BASELINK
);
1167 TREE_TYPE (baselink
) = TREE_TYPE (functions
);
1168 BASELINK_BINFO (baselink
) = binfo
;
1169 BASELINK_ACCESS_BINFO (baselink
) = access_binfo
;
1170 BASELINK_FUNCTIONS (baselink
) = functions
;
1171 BASELINK_OPTYPE (baselink
) = optype
;
1176 /* Look for a member named NAME in an inheritance lattice dominated by
1177 XBASETYPE. If PROTECT is 0 or two, we do not check access. If it
1178 is 1, we enforce accessibility. If PROTECT is zero, then, for an
1179 ambiguous lookup, we return NULL. If PROTECT is 1, we issue error
1180 messages about inaccessible or ambiguous lookup. If PROTECT is 2,
1181 we return a TREE_LIST whose TREE_TYPE is error_mark_node and whose
1182 TREE_VALUEs are the list of ambiguous candidates.
1184 WANT_TYPE is 1 when we should only return TYPE_DECLs.
1186 If nothing can be found return NULL_TREE and do not issue an error. */
1189 lookup_member (tree xbasetype
, tree name
, int protect
, bool want_type
)
1191 tree rval
, rval_binfo
= NULL_TREE
;
1192 tree type
= NULL_TREE
, basetype_path
= NULL_TREE
;
1193 struct lookup_field_info lfi
;
1195 /* rval_binfo is the binfo associated with the found member, note,
1196 this can be set with useful information, even when rval is not
1197 set, because it must deal with ALL members, not just non-function
1198 members. It is used for ambiguity checking and the hidden
1199 checks. Whereas rval is only set if a proper (not hidden)
1200 non-function member is found. */
1202 const char *errstr
= 0;
1204 if (name
== error_mark_node
)
1207 gcc_assert (TREE_CODE (name
) == IDENTIFIER_NODE
);
1209 if (TREE_CODE (xbasetype
) == TREE_BINFO
)
1211 type
= BINFO_TYPE (xbasetype
);
1212 basetype_path
= xbasetype
;
1216 if (!RECORD_OR_UNION_CODE_P (TREE_CODE (xbasetype
)))
1219 xbasetype
= NULL_TREE
;
1222 type
= complete_type (type
);
1224 basetype_path
= TYPE_BINFO (type
);
1229 #ifdef GATHER_STATISTICS
1230 n_calls_lookup_field
++;
1231 #endif /* GATHER_STATISTICS */
1233 memset (&lfi
, 0, sizeof (lfi
));
1236 lfi
.want_type
= want_type
;
1237 dfs_walk_all (basetype_path
, &lookup_field_r
, NULL
, &lfi
);
1239 rval_binfo
= lfi
.rval_binfo
;
1241 type
= BINFO_TYPE (rval_binfo
);
1242 errstr
= lfi
.errstr
;
1244 /* If we are not interested in ambiguities, don't report them;
1245 just return NULL_TREE. */
1246 if (!protect
&& lfi
.ambiguous
)
1252 return lfi
.ambiguous
;
1259 In the case of overloaded function names, access control is
1260 applied to the function selected by overloaded resolution.
1262 We cannot check here, even if RVAL is only a single non-static
1263 member function, since we do not know what the "this" pointer
1266 class A { protected: void f(); };
1267 class B : public A {
1274 only the first call to "f" is valid. However, if the function is
1275 static, we can check. */
1277 && !really_overloaded_fn (rval
)
1278 && !(TREE_CODE (rval
) == FUNCTION_DECL
1279 && DECL_NONSTATIC_MEMBER_FUNCTION_P (rval
)))
1280 perform_or_defer_access_check (basetype_path
, rval
, rval
);
1282 if (errstr
&& protect
)
1284 error (errstr
, name
, type
);
1286 print_candidates (lfi
.ambiguous
);
1287 rval
= error_mark_node
;
1290 if (rval
&& is_overloaded_fn (rval
))
1291 rval
= build_baselink (rval_binfo
, basetype_path
, rval
,
1292 (IDENTIFIER_TYPENAME_P (name
)
1293 ? TREE_TYPE (name
): NULL_TREE
));
1297 /* Like lookup_member, except that if we find a function member we
1298 return NULL_TREE. */
1301 lookup_field (tree xbasetype
, tree name
, int protect
, bool want_type
)
1303 tree rval
= lookup_member (xbasetype
, name
, protect
, want_type
);
1305 /* Ignore functions, but propagate the ambiguity list. */
1306 if (!error_operand_p (rval
)
1307 && (rval
&& BASELINK_P (rval
)))
1313 /* Like lookup_member, except that if we find a non-function member we
1314 return NULL_TREE. */
1317 lookup_fnfields (tree xbasetype
, tree name
, int protect
)
1319 tree rval
= lookup_member (xbasetype
, name
, protect
, /*want_type=*/false);
1321 /* Ignore non-functions, but propagate the ambiguity list. */
1322 if (!error_operand_p (rval
)
1323 && (rval
&& !BASELINK_P (rval
)))
1329 /* Return the index in the CLASSTYPE_METHOD_VEC for CLASS_TYPE
1330 corresponding to "operator TYPE ()", or -1 if there is no such
1331 operator. Only CLASS_TYPE itself is searched; this routine does
1332 not scan the base classes of CLASS_TYPE. */
1335 lookup_conversion_operator (tree class_type
, tree type
)
1339 if (TYPE_HAS_CONVERSION (class_type
))
1343 VEC(tree
,gc
) *methods
= CLASSTYPE_METHOD_VEC (class_type
);
1345 for (i
= CLASSTYPE_FIRST_CONVERSION_SLOT
;
1346 VEC_iterate (tree
, methods
, i
, fn
); ++i
)
1348 /* All the conversion operators come near the beginning of
1349 the class. Therefore, if FN is not a conversion
1350 operator, there is no matching conversion operator in
1352 fn
= OVL_CURRENT (fn
);
1353 if (!DECL_CONV_FN_P (fn
))
1356 if (TREE_CODE (fn
) == TEMPLATE_DECL
)
1357 /* All the templated conversion functions are on the same
1358 slot, so remember it. */
1360 else if (same_type_p (DECL_CONV_FN_TYPE (fn
), type
))
1368 /* TYPE is a class type. Return the index of the fields within
1369 the method vector with name NAME, or -1 is no such field exists. */
1372 lookup_fnfields_1 (tree type
, tree name
)
1374 VEC(tree
,gc
) *method_vec
;
1379 if (!CLASS_TYPE_P (type
))
1382 if (COMPLETE_TYPE_P (type
))
1384 if ((name
== ctor_identifier
1385 || name
== base_ctor_identifier
1386 || name
== complete_ctor_identifier
))
1388 if (CLASSTYPE_LAZY_DEFAULT_CTOR (type
))
1389 lazily_declare_fn (sfk_constructor
, type
);
1390 if (CLASSTYPE_LAZY_COPY_CTOR (type
))
1391 lazily_declare_fn (sfk_copy_constructor
, type
);
1393 else if (name
== ansi_assopname(NOP_EXPR
)
1394 && CLASSTYPE_LAZY_ASSIGNMENT_OP (type
))
1395 lazily_declare_fn (sfk_assignment_operator
, type
);
1396 else if ((name
== dtor_identifier
1397 || name
== base_dtor_identifier
1398 || name
== complete_dtor_identifier
1399 || name
== deleting_dtor_identifier
)
1400 && CLASSTYPE_LAZY_DESTRUCTOR (type
))
1401 lazily_declare_fn (sfk_destructor
, type
);
1404 method_vec
= CLASSTYPE_METHOD_VEC (type
);
1408 #ifdef GATHER_STATISTICS
1409 n_calls_lookup_fnfields_1
++;
1410 #endif /* GATHER_STATISTICS */
1412 /* Constructors are first... */
1413 if (name
== ctor_identifier
)
1415 fn
= CLASSTYPE_CONSTRUCTORS (type
);
1416 return fn
? CLASSTYPE_CONSTRUCTOR_SLOT
: -1;
1418 /* and destructors are second. */
1419 if (name
== dtor_identifier
)
1421 fn
= CLASSTYPE_DESTRUCTORS (type
);
1422 return fn
? CLASSTYPE_DESTRUCTOR_SLOT
: -1;
1424 if (IDENTIFIER_TYPENAME_P (name
))
1425 return lookup_conversion_operator (type
, TREE_TYPE (name
));
1427 /* Skip the conversion operators. */
1428 for (i
= CLASSTYPE_FIRST_CONVERSION_SLOT
;
1429 VEC_iterate (tree
, method_vec
, i
, fn
);
1431 if (!DECL_CONV_FN_P (OVL_CURRENT (fn
)))
1434 /* If the type is complete, use binary search. */
1435 if (COMPLETE_TYPE_P (type
))
1441 hi
= VEC_length (tree
, method_vec
);
1446 #ifdef GATHER_STATISTICS
1447 n_outer_fields_searched
++;
1448 #endif /* GATHER_STATISTICS */
1450 tmp
= VEC_index (tree
, method_vec
, i
);
1451 tmp
= DECL_NAME (OVL_CURRENT (tmp
));
1454 else if (tmp
< name
)
1461 for (; VEC_iterate (tree
, method_vec
, i
, fn
); ++i
)
1463 #ifdef GATHER_STATISTICS
1464 n_outer_fields_searched
++;
1465 #endif /* GATHER_STATISTICS */
1466 if (DECL_NAME (OVL_CURRENT (fn
)) == name
)
1473 /* Like lookup_fnfields_1, except that the name is extracted from
1474 FUNCTION, which is a FUNCTION_DECL or a TEMPLATE_DECL. */
1477 class_method_index_for_fn (tree class_type
, tree function
)
1479 gcc_assert (TREE_CODE (function
) == FUNCTION_DECL
1480 || DECL_FUNCTION_TEMPLATE_P (function
));
1482 return lookup_fnfields_1 (class_type
,
1483 DECL_CONSTRUCTOR_P (function
) ? ctor_identifier
:
1484 DECL_DESTRUCTOR_P (function
) ? dtor_identifier
:
1485 DECL_NAME (function
));
1489 /* DECL is the result of a qualified name lookup. QUALIFYING_SCOPE is
1490 the class or namespace used to qualify the name. CONTEXT_CLASS is
1491 the class corresponding to the object in which DECL will be used.
1492 Return a possibly modified version of DECL that takes into account
1495 In particular, consider an expression like `B::m' in the context of
1496 a derived class `D'. If `B::m' has been resolved to a BASELINK,
1497 then the most derived class indicated by the BASELINK_BINFO will be
1498 `B', not `D'. This function makes that adjustment. */
1501 adjust_result_of_qualified_name_lookup (tree decl
,
1502 tree qualifying_scope
,
1505 if (context_class
&& context_class
!= error_mark_node
1506 && CLASS_TYPE_P (context_class
)
1507 && CLASS_TYPE_P (qualifying_scope
)
1508 && DERIVED_FROM_P (qualifying_scope
, context_class
)
1509 && BASELINK_P (decl
))
1513 /* Look for the QUALIFYING_SCOPE as a base of the CONTEXT_CLASS.
1514 Because we do not yet know which function will be chosen by
1515 overload resolution, we cannot yet check either accessibility
1516 or ambiguity -- in either case, the choice of a static member
1517 function might make the usage valid. */
1518 base
= lookup_base (context_class
, qualifying_scope
,
1519 ba_unique
| ba_quiet
, NULL
);
1522 BASELINK_ACCESS_BINFO (decl
) = base
;
1523 BASELINK_BINFO (decl
)
1524 = lookup_base (base
, BINFO_TYPE (BASELINK_BINFO (decl
)),
1525 ba_unique
| ba_quiet
,
1534 /* Walk the class hierarchy within BINFO, in a depth-first traversal.
1535 PRE_FN is called in preorder, while POST_FN is called in postorder.
1536 If PRE_FN returns DFS_SKIP_BASES, child binfos will not be
1537 walked. If PRE_FN or POST_FN returns a different non-NULL value,
1538 that value is immediately returned and the walk is terminated. One
1539 of PRE_FN and POST_FN can be NULL. At each node, PRE_FN and
1540 POST_FN are passed the binfo to examine and the caller's DATA
1541 value. All paths are walked, thus virtual and morally virtual
1542 binfos can be multiply walked. */
1545 dfs_walk_all (tree binfo
, tree (*pre_fn
) (tree
, void *),
1546 tree (*post_fn
) (tree
, void *), void *data
)
1552 /* Call the pre-order walking function. */
1555 rval
= pre_fn (binfo
, data
);
1558 if (rval
== dfs_skip_bases
)
1564 /* Find the next child binfo to walk. */
1565 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1567 rval
= dfs_walk_all (base_binfo
, pre_fn
, post_fn
, data
);
1573 /* Call the post-order walking function. */
1576 rval
= post_fn (binfo
, data
);
1577 gcc_assert (rval
!= dfs_skip_bases
);
1584 /* Worker for dfs_walk_once. This behaves as dfs_walk_all, except
1585 that binfos are walked at most once. */
1588 dfs_walk_once_r (tree binfo
, tree (*pre_fn
) (tree
, void *),
1589 tree (*post_fn
) (tree
, void *), void *data
)
1595 /* Call the pre-order walking function. */
1598 rval
= pre_fn (binfo
, data
);
1601 if (rval
== dfs_skip_bases
)
1608 /* Find the next child binfo to walk. */
1609 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1611 if (BINFO_VIRTUAL_P (base_binfo
))
1613 if (BINFO_MARKED (base_binfo
))
1615 BINFO_MARKED (base_binfo
) = 1;
1618 rval
= dfs_walk_once_r (base_binfo
, pre_fn
, post_fn
, data
);
1624 /* Call the post-order walking function. */
1627 rval
= post_fn (binfo
, data
);
1628 gcc_assert (rval
!= dfs_skip_bases
);
1635 /* Worker for dfs_walk_once. Recursively unmark the virtual base binfos of
1639 dfs_unmark_r (tree binfo
)
1644 /* Process the basetypes. */
1645 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1647 if (BINFO_VIRTUAL_P (base_binfo
))
1649 if (!BINFO_MARKED (base_binfo
))
1651 BINFO_MARKED (base_binfo
) = 0;
1653 /* Only walk, if it can contain more virtual bases. */
1654 if (CLASSTYPE_VBASECLASSES (BINFO_TYPE (base_binfo
)))
1655 dfs_unmark_r (base_binfo
);
1659 /* Like dfs_walk_all, except that binfos are not multiply walked. For
1660 non-diamond shaped hierarchies this is the same as dfs_walk_all.
1661 For diamond shaped hierarchies we must mark the virtual bases, to
1662 avoid multiple walks. */
1665 dfs_walk_once (tree binfo
, tree (*pre_fn
) (tree
, void *),
1666 tree (*post_fn
) (tree
, void *), void *data
)
1668 static int active
= 0; /* We must not be called recursively. */
1671 gcc_assert (pre_fn
|| post_fn
);
1672 gcc_assert (!active
);
1675 if (!CLASSTYPE_DIAMOND_SHAPED_P (BINFO_TYPE (binfo
)))
1676 /* We are not diamond shaped, and therefore cannot encounter the
1677 same binfo twice. */
1678 rval
= dfs_walk_all (binfo
, pre_fn
, post_fn
, data
);
1681 rval
= dfs_walk_once_r (binfo
, pre_fn
, post_fn
, data
);
1682 if (!BINFO_INHERITANCE_CHAIN (binfo
))
1684 /* We are at the top of the hierarchy, and can use the
1685 CLASSTYPE_VBASECLASSES list for unmarking the virtual
1687 VEC(tree
,gc
) *vbases
;
1691 for (vbases
= CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo
)), ix
= 0;
1692 VEC_iterate (tree
, vbases
, ix
, base_binfo
); ix
++)
1693 BINFO_MARKED (base_binfo
) = 0;
1696 dfs_unmark_r (binfo
);
1704 /* Worker function for dfs_walk_once_accessible. Behaves like
1705 dfs_walk_once_r, except (a) FRIENDS_P is true if special
1706 access given by the current context should be considered, (b) ONCE
1707 indicates whether bases should be marked during traversal. */
1710 dfs_walk_once_accessible_r (tree binfo
, bool friends_p
, bool once
,
1711 tree (*pre_fn
) (tree
, void *),
1712 tree (*post_fn
) (tree
, void *), void *data
)
1714 tree rval
= NULL_TREE
;
1718 /* Call the pre-order walking function. */
1721 rval
= pre_fn (binfo
, data
);
1724 if (rval
== dfs_skip_bases
)
1731 /* Find the next child binfo to walk. */
1732 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1734 bool mark
= once
&& BINFO_VIRTUAL_P (base_binfo
);
1736 if (mark
&& BINFO_MARKED (base_binfo
))
1739 /* If the base is inherited via private or protected
1740 inheritance, then we can't see it, unless we are a friend of
1741 the current binfo. */
1742 if (BINFO_BASE_ACCESS (binfo
, ix
) != access_public_node
)
1747 scope
= current_scope ();
1749 || TREE_CODE (scope
) == NAMESPACE_DECL
1750 || !is_friend (BINFO_TYPE (binfo
), scope
))
1755 BINFO_MARKED (base_binfo
) = 1;
1757 rval
= dfs_walk_once_accessible_r (base_binfo
, friends_p
, once
,
1758 pre_fn
, post_fn
, data
);
1764 /* Call the post-order walking function. */
1767 rval
= post_fn (binfo
, data
);
1768 gcc_assert (rval
!= dfs_skip_bases
);
1775 /* Like dfs_walk_once except that only accessible bases are walked.
1776 FRIENDS_P indicates whether friendship of the local context
1777 should be considered when determining accessibility. */
1780 dfs_walk_once_accessible (tree binfo
, bool friends_p
,
1781 tree (*pre_fn
) (tree
, void *),
1782 tree (*post_fn
) (tree
, void *), void *data
)
1784 bool diamond_shaped
= CLASSTYPE_DIAMOND_SHAPED_P (BINFO_TYPE (binfo
));
1785 tree rval
= dfs_walk_once_accessible_r (binfo
, friends_p
, diamond_shaped
,
1786 pre_fn
, post_fn
, data
);
1790 if (!BINFO_INHERITANCE_CHAIN (binfo
))
1792 /* We are at the top of the hierarchy, and can use the
1793 CLASSTYPE_VBASECLASSES list for unmarking the virtual
1795 VEC(tree
,gc
) *vbases
;
1799 for (vbases
= CLASSTYPE_VBASECLASSES (BINFO_TYPE (binfo
)), ix
= 0;
1800 VEC_iterate (tree
, vbases
, ix
, base_binfo
); ix
++)
1801 BINFO_MARKED (base_binfo
) = 0;
1804 dfs_unmark_r (binfo
);
1809 /* Check that virtual overrider OVERRIDER is acceptable for base function
1810 BASEFN. Issue diagnostic, and return zero, if unacceptable. */
1813 check_final_overrider (tree overrider
, tree basefn
)
1815 tree over_type
= TREE_TYPE (overrider
);
1816 tree base_type
= TREE_TYPE (basefn
);
1817 tree over_return
= TREE_TYPE (over_type
);
1818 tree base_return
= TREE_TYPE (base_type
);
1819 tree over_throw
= TYPE_RAISES_EXCEPTIONS (over_type
);
1820 tree base_throw
= TYPE_RAISES_EXCEPTIONS (base_type
);
1823 if (DECL_INVALID_OVERRIDER_P (overrider
))
1826 if (same_type_p (base_return
, over_return
))
1828 else if ((CLASS_TYPE_P (over_return
) && CLASS_TYPE_P (base_return
))
1829 || (TREE_CODE (base_return
) == TREE_CODE (over_return
)
1830 && POINTER_TYPE_P (base_return
)))
1832 /* Potentially covariant. */
1833 unsigned base_quals
, over_quals
;
1835 fail
= !POINTER_TYPE_P (base_return
);
1838 fail
= cp_type_quals (base_return
) != cp_type_quals (over_return
);
1840 base_return
= TREE_TYPE (base_return
);
1841 over_return
= TREE_TYPE (over_return
);
1843 base_quals
= cp_type_quals (base_return
);
1844 over_quals
= cp_type_quals (over_return
);
1846 if ((base_quals
& over_quals
) != over_quals
)
1849 if (CLASS_TYPE_P (base_return
) && CLASS_TYPE_P (over_return
))
1851 tree binfo
= lookup_base (over_return
, base_return
,
1852 ba_check
| ba_quiet
, NULL
);
1858 && can_convert (TREE_TYPE (base_type
), TREE_TYPE (over_type
)))
1859 /* GNU extension, allow trivial pointer conversions such as
1860 converting to void *, or qualification conversion. */
1862 /* can_convert will permit user defined conversion from a
1863 (reference to) class type. We must reject them. */
1864 over_return
= non_reference (TREE_TYPE (over_type
));
1865 if (CLASS_TYPE_P (over_return
))
1869 warning (0, "deprecated covariant return type for %q+#D",
1871 warning (0, " overriding %q+#D", basefn
);
1885 error ("invalid covariant return type for %q+#D", overrider
);
1886 error (" overriding %q+#D", basefn
);
1890 error ("conflicting return type specified for %q+#D", overrider
);
1891 error (" overriding %q+#D", basefn
);
1893 DECL_INVALID_OVERRIDER_P (overrider
) = 1;
1897 /* Check throw specifier is at least as strict. */
1898 if (!comp_except_specs (base_throw
, over_throw
, 0))
1900 error ("looser throw specifier for %q+#F", overrider
);
1901 error (" overriding %q+#F", basefn
);
1902 DECL_INVALID_OVERRIDER_P (overrider
) = 1;
1906 /* Check for conflicting type attributes. */
1907 if (!targetm
.comp_type_attributes (over_type
, base_type
))
1909 error ("conflicting type attributes specified for %q+#D", overrider
);
1910 error (" overriding %q+#D", basefn
);
1911 DECL_INVALID_OVERRIDER_P (overrider
) = 1;
1915 if (DECL_DELETED_FN (basefn
) != DECL_DELETED_FN (overrider
))
1917 if (DECL_DELETED_FN (overrider
))
1919 error ("deleted function %q+D", overrider
);
1920 error ("overriding non-deleted function %q+D", basefn
);
1924 error ("non-deleted function %q+D", overrider
);
1925 error ("overriding deleted function %q+D", basefn
);
1932 /* Given a class TYPE, and a function decl FNDECL, look for
1933 virtual functions in TYPE's hierarchy which FNDECL overrides.
1934 We do not look in TYPE itself, only its bases.
1936 Returns nonzero, if we find any. Set FNDECL's DECL_VIRTUAL_P, if we
1937 find that it overrides anything.
1939 We check that every function which is overridden, is correctly
1943 look_for_overrides (tree type
, tree fndecl
)
1945 tree binfo
= TYPE_BINFO (type
);
1950 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1952 tree basetype
= BINFO_TYPE (base_binfo
);
1954 if (TYPE_POLYMORPHIC_P (basetype
))
1955 found
+= look_for_overrides_r (basetype
, fndecl
);
1960 /* Look in TYPE for virtual functions with the same signature as
1964 look_for_overrides_here (tree type
, tree fndecl
)
1968 /* If there are no methods in TYPE (meaning that only implicitly
1969 declared methods will ever be provided for TYPE), then there are
1970 no virtual functions. */
1971 if (!CLASSTYPE_METHOD_VEC (type
))
1974 if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fndecl
))
1975 ix
= CLASSTYPE_DESTRUCTOR_SLOT
;
1977 ix
= lookup_fnfields_1 (type
, DECL_NAME (fndecl
));
1980 tree fns
= VEC_index (tree
, CLASSTYPE_METHOD_VEC (type
), ix
);
1982 for (; fns
; fns
= OVL_NEXT (fns
))
1984 tree fn
= OVL_CURRENT (fns
);
1986 if (!DECL_VIRTUAL_P (fn
))
1987 /* Not a virtual. */;
1988 else if (DECL_CONTEXT (fn
) != type
)
1989 /* Introduced with a using declaration. */;
1990 else if (DECL_STATIC_FUNCTION_P (fndecl
))
1992 tree btypes
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
1993 tree dtypes
= TYPE_ARG_TYPES (TREE_TYPE (fndecl
));
1994 if (compparms (TREE_CHAIN (btypes
), dtypes
))
1997 else if (same_signature_p (fndecl
, fn
))
2004 /* Look in TYPE for virtual functions overridden by FNDECL. Check both
2005 TYPE itself and its bases. */
2008 look_for_overrides_r (tree type
, tree fndecl
)
2010 tree fn
= look_for_overrides_here (type
, fndecl
);
2013 if (DECL_STATIC_FUNCTION_P (fndecl
))
2015 /* A static member function cannot match an inherited
2016 virtual member function. */
2017 error ("%q+#D cannot be declared", fndecl
);
2018 error (" since %q+#D declared in base class", fn
);
2022 /* It's definitely virtual, even if not explicitly set. */
2023 DECL_VIRTUAL_P (fndecl
) = 1;
2024 check_final_overrider (fndecl
, fn
);
2029 /* We failed to find one declared in this class. Look in its bases. */
2030 return look_for_overrides (type
, fndecl
);
2033 /* Called via dfs_walk from dfs_get_pure_virtuals. */
2036 dfs_get_pure_virtuals (tree binfo
, void *data
)
2038 tree type
= (tree
) data
;
2040 /* We're not interested in primary base classes; the derived class
2041 of which they are a primary base will contain the information we
2043 if (!BINFO_PRIMARY_P (binfo
))
2047 for (virtuals
= BINFO_VIRTUALS (binfo
);
2049 virtuals
= TREE_CHAIN (virtuals
))
2050 if (DECL_PURE_VIRTUAL_P (BV_FN (virtuals
)))
2051 VEC_safe_push (tree
, gc
, CLASSTYPE_PURE_VIRTUALS (type
),
2058 /* Set CLASSTYPE_PURE_VIRTUALS for TYPE. */
2061 get_pure_virtuals (tree type
)
2063 /* Clear the CLASSTYPE_PURE_VIRTUALS list; whatever is already there
2064 is going to be overridden. */
2065 CLASSTYPE_PURE_VIRTUALS (type
) = NULL
;
2066 /* Now, run through all the bases which are not primary bases, and
2067 collect the pure virtual functions. We look at the vtable in
2068 each class to determine what pure virtual functions are present.
2069 (A primary base is not interesting because the derived class of
2070 which it is a primary base will contain vtable entries for the
2071 pure virtuals in the base class. */
2072 dfs_walk_once (TYPE_BINFO (type
), NULL
, dfs_get_pure_virtuals
, type
);
2075 /* Debug info for C++ classes can get very large; try to avoid
2076 emitting it everywhere.
2078 Note that this optimization wins even when the target supports
2079 BINCL (if only slightly), and reduces the amount of work for the
2083 maybe_suppress_debug_info (tree t
)
2085 if (write_symbols
== NO_DEBUG
)
2088 /* We might have set this earlier in cp_finish_decl. */
2089 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t
)) = 0;
2091 /* Always emit the information for each class every time. */
2092 if (flag_emit_class_debug_always
)
2095 /* If we already know how we're handling this class, handle debug info
2097 if (CLASSTYPE_INTERFACE_KNOWN (t
))
2099 if (CLASSTYPE_INTERFACE_ONLY (t
))
2100 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t
)) = 1;
2101 /* else don't set it. */
2103 /* If the class has a vtable, write out the debug info along with
2105 else if (TYPE_CONTAINS_VPTR_P (t
))
2106 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t
)) = 1;
2108 /* Otherwise, just emit the debug info normally. */
2111 /* Note that we want debugging information for a base class of a class
2112 whose vtable is being emitted. Normally, this would happen because
2113 calling the constructor for a derived class implies calling the
2114 constructors for all bases, which involve initializing the
2115 appropriate vptr with the vtable for the base class; but in the
2116 presence of optimization, this initialization may be optimized
2117 away, so we tell finish_vtable_vardecl that we want the debugging
2118 information anyway. */
2121 dfs_debug_mark (tree binfo
, void *data ATTRIBUTE_UNUSED
)
2123 tree t
= BINFO_TYPE (binfo
);
2125 if (CLASSTYPE_DEBUG_REQUESTED (t
))
2126 return dfs_skip_bases
;
2128 CLASSTYPE_DEBUG_REQUESTED (t
) = 1;
2133 /* Write out the debugging information for TYPE, whose vtable is being
2134 emitted. Also walk through our bases and note that we want to
2135 write out information for them. This avoids the problem of not
2136 writing any debug info for intermediate basetypes whose
2137 constructors, and thus the references to their vtables, and thus
2138 the vtables themselves, were optimized away. */
2141 note_debug_info_needed (tree type
)
2143 if (TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type
)))
2145 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type
)) = 0;
2146 rest_of_type_compilation (type
, toplevel_bindings_p ());
2149 dfs_walk_all (TYPE_BINFO (type
), dfs_debug_mark
, NULL
, 0);
2153 print_search_statistics (void)
2155 #ifdef GATHER_STATISTICS
2156 fprintf (stderr
, "%d fields searched in %d[%d] calls to lookup_field[_1]\n",
2157 n_fields_searched
, n_calls_lookup_field
, n_calls_lookup_field_1
);
2158 fprintf (stderr
, "%d fnfields searched in %d calls to lookup_fnfields\n",
2159 n_outer_fields_searched
, n_calls_lookup_fnfields
);
2160 fprintf (stderr
, "%d calls to get_base_type\n", n_calls_get_base_type
);
2161 #else /* GATHER_STATISTICS */
2162 fprintf (stderr
, "no search statistics\n");
2163 #endif /* GATHER_STATISTICS */
2167 reinit_search_statistics (void)
2169 #ifdef GATHER_STATISTICS
2170 n_fields_searched
= 0;
2171 n_calls_lookup_field
= 0, n_calls_lookup_field_1
= 0;
2172 n_calls_lookup_fnfields
= 0, n_calls_lookup_fnfields_1
= 0;
2173 n_calls_get_base_type
= 0;
2174 n_outer_fields_searched
= 0;
2175 n_contexts_saved
= 0;
2176 #endif /* GATHER_STATISTICS */
2179 /* Helper for lookup_conversions_r. TO_TYPE is the type converted to
2180 by a conversion op in base BINFO. VIRTUAL_DEPTH is nonzero if
2181 BINFO is morally virtual, and VIRTUALNESS is nonzero if virtual
2182 bases have been encountered already in the tree walk. PARENT_CONVS
2183 is the list of lists of conversion functions that could hide CONV
2184 and OTHER_CONVS is the list of lists of conversion functions that
2185 could hide or be hidden by CONV, should virtualness be involved in
2186 the hierarchy. Merely checking the conversion op's name is not
2187 enough because two conversion operators to the same type can have
2188 different names. Return nonzero if we are visible. */
2191 check_hidden_convs (tree binfo
, int virtual_depth
, int virtualness
,
2192 tree to_type
, tree parent_convs
, tree other_convs
)
2196 /* See if we are hidden by a parent conversion. */
2197 for (level
= parent_convs
; level
; level
= TREE_CHAIN (level
))
2198 for (probe
= TREE_VALUE (level
); probe
; probe
= TREE_CHAIN (probe
))
2199 if (same_type_p (to_type
, TREE_TYPE (probe
)))
2202 if (virtual_depth
|| virtualness
)
2204 /* In a virtual hierarchy, we could be hidden, or could hide a
2205 conversion function on the other_convs list. */
2206 for (level
= other_convs
; level
; level
= TREE_CHAIN (level
))
2212 if (!(virtual_depth
|| TREE_STATIC (level
)))
2213 /* Neither is morally virtual, so cannot hide each other. */
2216 if (!TREE_VALUE (level
))
2217 /* They evaporated away already. */
2220 they_hide_us
= (virtual_depth
2221 && original_binfo (binfo
, TREE_PURPOSE (level
)));
2222 we_hide_them
= (!they_hide_us
&& TREE_STATIC (level
)
2223 && original_binfo (TREE_PURPOSE (level
), binfo
));
2225 if (!(we_hide_them
|| they_hide_us
))
2226 /* Neither is within the other, so no hiding can occur. */
2229 for (prev
= &TREE_VALUE (level
), other
= *prev
; other
;)
2231 if (same_type_p (to_type
, TREE_TYPE (other
)))
2234 /* We are hidden. */
2239 /* We hide the other one. */
2240 other
= TREE_CHAIN (other
);
2245 prev
= &TREE_CHAIN (other
);
2253 /* Helper for lookup_conversions_r. PARENT_CONVS is a list of lists
2254 of conversion functions, the first slot will be for the current
2255 binfo, if MY_CONVS is non-NULL. CHILD_CONVS is the list of lists
2256 of conversion functions from children of the current binfo,
2257 concatenated with conversions from elsewhere in the hierarchy --
2258 that list begins with OTHER_CONVS. Return a single list of lists
2259 containing only conversions from the current binfo and its
2263 split_conversions (tree my_convs
, tree parent_convs
,
2264 tree child_convs
, tree other_convs
)
2269 /* Remove the original other_convs portion from child_convs. */
2270 for (prev
= NULL
, t
= child_convs
;
2271 t
!= other_convs
; prev
= t
, t
= TREE_CHAIN (t
))
2275 TREE_CHAIN (prev
) = NULL_TREE
;
2277 child_convs
= NULL_TREE
;
2279 /* Attach the child convs to any we had at this level. */
2282 my_convs
= parent_convs
;
2283 TREE_CHAIN (my_convs
) = child_convs
;
2286 my_convs
= child_convs
;
2291 /* Worker for lookup_conversions. Lookup conversion functions in
2292 BINFO and its children. VIRTUAL_DEPTH is nonzero, if BINFO is in
2293 a morally virtual base, and VIRTUALNESS is nonzero, if we've
2294 encountered virtual bases already in the tree walk. PARENT_CONVS &
2295 PARENT_TPL_CONVS are lists of list of conversions within parent
2296 binfos. OTHER_CONVS and OTHER_TPL_CONVS are conversions found
2297 elsewhere in the tree. Return the conversions found within this
2298 portion of the graph in CONVS and TPL_CONVS. Return nonzero is we
2299 encountered virtualness. We keep template and non-template
2300 conversions separate, to avoid unnecessary type comparisons.
2302 The located conversion functions are held in lists of lists. The
2303 TREE_VALUE of the outer list is the list of conversion functions
2304 found in a particular binfo. The TREE_PURPOSE of both the outer
2305 and inner lists is the binfo at which those conversions were
2306 found. TREE_STATIC is set for those lists within of morally
2307 virtual binfos. The TREE_VALUE of the inner list is the conversion
2308 function or overload itself. The TREE_TYPE of each inner list node
2309 is the converted-to type. */
2312 lookup_conversions_r (tree binfo
,
2313 int virtual_depth
, int virtualness
,
2314 tree parent_convs
, tree parent_tpl_convs
,
2315 tree other_convs
, tree other_tpl_convs
,
2316 tree
*convs
, tree
*tpl_convs
)
2318 int my_virtualness
= 0;
2319 tree my_convs
= NULL_TREE
;
2320 tree my_tpl_convs
= NULL_TREE
;
2321 tree child_convs
= NULL_TREE
;
2322 tree child_tpl_convs
= NULL_TREE
;
2325 VEC(tree
,gc
) *method_vec
= CLASSTYPE_METHOD_VEC (BINFO_TYPE (binfo
));
2328 /* If we have no conversion operators, then don't look. */
2329 if (!TYPE_HAS_CONVERSION (BINFO_TYPE (binfo
)))
2331 *convs
= *tpl_convs
= NULL_TREE
;
2336 if (BINFO_VIRTUAL_P (binfo
))
2339 /* First, locate the unhidden ones at this level. */
2340 for (i
= CLASSTYPE_FIRST_CONVERSION_SLOT
;
2341 VEC_iterate (tree
, method_vec
, i
, conv
);
2344 tree cur
= OVL_CURRENT (conv
);
2346 if (!DECL_CONV_FN_P (cur
))
2349 if (TREE_CODE (cur
) == TEMPLATE_DECL
)
2351 /* Only template conversions can be overloaded, and we must
2352 flatten them out and check each one individually. */
2355 for (tpls
= conv
; tpls
; tpls
= OVL_NEXT (tpls
))
2357 tree tpl
= OVL_CURRENT (tpls
);
2358 tree type
= DECL_CONV_FN_TYPE (tpl
);
2360 if (check_hidden_convs (binfo
, virtual_depth
, virtualness
,
2361 type
, parent_tpl_convs
, other_tpl_convs
))
2363 my_tpl_convs
= tree_cons (binfo
, tpl
, my_tpl_convs
);
2364 TREE_TYPE (my_tpl_convs
) = type
;
2367 TREE_STATIC (my_tpl_convs
) = 1;
2375 tree name
= DECL_NAME (cur
);
2377 if (!IDENTIFIER_MARKED (name
))
2379 tree type
= DECL_CONV_FN_TYPE (cur
);
2381 if (check_hidden_convs (binfo
, virtual_depth
, virtualness
,
2382 type
, parent_convs
, other_convs
))
2384 my_convs
= tree_cons (binfo
, conv
, my_convs
);
2385 TREE_TYPE (my_convs
) = type
;
2388 TREE_STATIC (my_convs
) = 1;
2391 IDENTIFIER_MARKED (name
) = 1;
2399 parent_convs
= tree_cons (binfo
, my_convs
, parent_convs
);
2401 TREE_STATIC (parent_convs
) = 1;
2406 parent_tpl_convs
= tree_cons (binfo
, my_tpl_convs
, parent_tpl_convs
);
2408 TREE_STATIC (parent_tpl_convs
) = 1;
2411 child_convs
= other_convs
;
2412 child_tpl_convs
= other_tpl_convs
;
2414 /* Now iterate over each base, looking for more conversions. */
2415 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
2417 tree base_convs
, base_tpl_convs
;
2418 unsigned base_virtualness
;
2420 base_virtualness
= lookup_conversions_r (base_binfo
,
2421 virtual_depth
, virtualness
,
2422 parent_convs
, parent_tpl_convs
,
2423 child_convs
, child_tpl_convs
,
2424 &base_convs
, &base_tpl_convs
);
2425 if (base_virtualness
)
2426 my_virtualness
= virtualness
= 1;
2427 child_convs
= chainon (base_convs
, child_convs
);
2428 child_tpl_convs
= chainon (base_tpl_convs
, child_tpl_convs
);
2431 /* Unmark the conversions found at this level */
2432 for (conv
= my_convs
; conv
; conv
= TREE_CHAIN (conv
))
2433 IDENTIFIER_MARKED (DECL_NAME (OVL_CURRENT (TREE_VALUE (conv
)))) = 0;
2435 *convs
= split_conversions (my_convs
, parent_convs
,
2436 child_convs
, other_convs
);
2437 *tpl_convs
= split_conversions (my_tpl_convs
, parent_tpl_convs
,
2438 child_tpl_convs
, other_tpl_convs
);
2440 return my_virtualness
;
2443 /* Return a TREE_LIST containing all the non-hidden user-defined
2444 conversion functions for TYPE (and its base-classes). The
2445 TREE_VALUE of each node is the FUNCTION_DECL of the conversion
2446 function. The TREE_PURPOSE is the BINFO from which the conversion
2447 functions in this node were selected. This function is effectively
2448 performing a set of member lookups as lookup_fnfield does, but
2449 using the type being converted to as the unique key, rather than the
2453 lookup_conversions (tree type
)
2455 tree convs
, tpl_convs
;
2456 tree list
= NULL_TREE
;
2458 complete_type (type
);
2459 if (!TYPE_BINFO (type
))
2462 lookup_conversions_r (TYPE_BINFO (type
), 0, 0,
2463 NULL_TREE
, NULL_TREE
, NULL_TREE
, NULL_TREE
,
2464 &convs
, &tpl_convs
);
2466 /* Flatten the list-of-lists */
2467 for (; convs
; convs
= TREE_CHAIN (convs
))
2471 for (probe
= TREE_VALUE (convs
); probe
; probe
= next
)
2473 next
= TREE_CHAIN (probe
);
2475 TREE_CHAIN (probe
) = list
;
2480 for (; tpl_convs
; tpl_convs
= TREE_CHAIN (tpl_convs
))
2484 for (probe
= TREE_VALUE (tpl_convs
); probe
; probe
= next
)
2486 next
= TREE_CHAIN (probe
);
2488 TREE_CHAIN (probe
) = list
;
2496 /* Returns the binfo of the first direct or indirect virtual base derived
2497 from BINFO, or NULL if binfo is not via virtual. */
2500 binfo_from_vbase (tree binfo
)
2502 for (; binfo
; binfo
= BINFO_INHERITANCE_CHAIN (binfo
))
2504 if (BINFO_VIRTUAL_P (binfo
))
2510 /* Returns the binfo of the first direct or indirect virtual base derived
2511 from BINFO up to the TREE_TYPE, LIMIT, or NULL if binfo is not
2515 binfo_via_virtual (tree binfo
, tree limit
)
2517 if (limit
&& !CLASSTYPE_VBASECLASSES (limit
))
2518 /* LIMIT has no virtual bases, so BINFO cannot be via one. */
2521 for (; binfo
&& !SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), limit
);
2522 binfo
= BINFO_INHERITANCE_CHAIN (binfo
))
2524 if (BINFO_VIRTUAL_P (binfo
))
2530 /* BINFO is a base binfo in the complete type BINFO_TYPE (HERE).
2531 Find the equivalent binfo within whatever graph HERE is located.
2532 This is the inverse of original_binfo. */
2535 copied_binfo (tree binfo
, tree here
)
2537 tree result
= NULL_TREE
;
2539 if (BINFO_VIRTUAL_P (binfo
))
2543 for (t
= here
; BINFO_INHERITANCE_CHAIN (t
);
2544 t
= BINFO_INHERITANCE_CHAIN (t
))
2547 result
= binfo_for_vbase (BINFO_TYPE (binfo
), BINFO_TYPE (t
));
2549 else if (BINFO_INHERITANCE_CHAIN (binfo
))
2555 cbinfo
= copied_binfo (BINFO_INHERITANCE_CHAIN (binfo
), here
);
2556 for (ix
= 0; BINFO_BASE_ITERATE (cbinfo
, ix
, base_binfo
); ix
++)
2557 if (SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo
), BINFO_TYPE (binfo
)))
2559 result
= base_binfo
;
2565 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (here
), BINFO_TYPE (binfo
)));
2569 gcc_assert (result
);
2574 binfo_for_vbase (tree base
, tree t
)
2578 VEC(tree
,gc
) *vbases
;
2580 for (vbases
= CLASSTYPE_VBASECLASSES (t
), ix
= 0;
2581 VEC_iterate (tree
, vbases
, ix
, binfo
); ix
++)
2582 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), base
))
2587 /* BINFO is some base binfo of HERE, within some other
2588 hierarchy. Return the equivalent binfo, but in the hierarchy
2589 dominated by HERE. This is the inverse of copied_binfo. If BINFO
2590 is not a base binfo of HERE, returns NULL_TREE. */
2593 original_binfo (tree binfo
, tree here
)
2597 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), BINFO_TYPE (here
)))
2599 else if (BINFO_VIRTUAL_P (binfo
))
2600 result
= (CLASSTYPE_VBASECLASSES (BINFO_TYPE (here
))
2601 ? binfo_for_vbase (BINFO_TYPE (binfo
), BINFO_TYPE (here
))
2603 else if (BINFO_INHERITANCE_CHAIN (binfo
))
2607 base_binfos
= original_binfo (BINFO_INHERITANCE_CHAIN (binfo
), here
);
2613 for (ix
= 0; (base_binfo
= BINFO_BASE_BINFO (base_binfos
, ix
)); ix
++)
2614 if (SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo
),
2615 BINFO_TYPE (binfo
)))
2617 result
= base_binfo
;