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 Free Software Foundation, Inc.
5 Contributed by Michael Tiemann (tiemann@cygnus.com)
7 This file is part of GNU CC.
9 GNU CC 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 2, or (at your option)
14 GNU CC 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 GNU CC; see the file COPYING. If not, write to
21 the Free Software Foundation, 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
24 /* High-level class interface. */
36 #define obstack_chunk_alloc xmalloc
37 #define obstack_chunk_free free
41 /* Obstack used for remembering decision points of breadth-first. */
43 static struct obstack search_obstack
;
45 /* Methods for pushing and popping objects to and from obstacks. */
48 push_stack_level (obstack
, tp
, size
)
49 struct obstack
*obstack
;
50 char *tp
; /* Sony NewsOS 5.0 compiler doesn't like void * here. */
53 struct stack_level
*stack
;
54 obstack_grow (obstack
, tp
, size
);
55 stack
= (struct stack_level
*) ((char*)obstack_next_free (obstack
) - size
);
56 obstack_finish (obstack
);
57 stack
->obstack
= obstack
;
58 stack
->first
= (tree
*) obstack_base (obstack
);
59 stack
->limit
= obstack_room (obstack
) / sizeof (tree
*);
64 pop_stack_level (stack
)
65 struct stack_level
*stack
;
67 struct stack_level
*tem
= stack
;
68 struct obstack
*obstack
= tem
->obstack
;
70 obstack_free (obstack
, tem
);
74 #define search_level stack_level
75 static struct search_level
*search_stack
;
79 /* The class dominating the hierarchy. */
81 /* A pointer to a complete object of the indicated TYPE. */
86 static tree lookup_field_1
PARAMS ((tree
, tree
));
87 static int is_subobject_of_p
PARAMS ((tree
, tree
, tree
));
88 static tree dfs_check_overlap
PARAMS ((tree
, void *));
89 static tree dfs_no_overlap_yet
PARAMS ((tree
, void *));
90 static base_kind lookup_base_r
91 PARAMS ((tree
, tree
, base_access
, int, int, int, tree
*));
92 static int dynamic_cast_base_recurse
PARAMS ((tree
, tree
, int, tree
*));
93 static tree marked_pushdecls_p
PARAMS ((tree
, void *));
94 static tree unmarked_pushdecls_p
PARAMS ((tree
, void *));
95 static tree dfs_debug_unmarkedp
PARAMS ((tree
, void *));
96 static tree dfs_debug_mark
PARAMS ((tree
, void *));
97 static tree dfs_get_vbase_types
PARAMS ((tree
, void *));
98 static tree dfs_push_type_decls
PARAMS ((tree
, void *));
99 static tree dfs_push_decls
PARAMS ((tree
, void *));
100 static tree dfs_unuse_fields
PARAMS ((tree
, void *));
101 static tree add_conversions
PARAMS ((tree
, void *));
102 static int covariant_return_p
PARAMS ((tree
, tree
));
103 static int look_for_overrides_r
PARAMS ((tree
, tree
));
104 static struct search_level
*push_search_level
105 PARAMS ((struct stack_level
*, struct obstack
*));
106 static struct search_level
*pop_search_level
107 PARAMS ((struct stack_level
*));
109 PARAMS ((tree
, tree (*) (tree
, void *), tree (*) (tree
, void *),
111 static tree lookup_field_queue_p
PARAMS ((tree
, void *));
112 static int shared_member_p
PARAMS ((tree
));
113 static tree lookup_field_r
PARAMS ((tree
, void *));
114 static tree canonical_binfo
PARAMS ((tree
));
115 static tree shared_marked_p
PARAMS ((tree
, void *));
116 static tree shared_unmarked_p
PARAMS ((tree
, void *));
117 static int dependent_base_p
PARAMS ((tree
));
118 static tree dfs_accessible_queue_p
PARAMS ((tree
, void *));
119 static tree dfs_accessible_p
PARAMS ((tree
, void *));
120 static tree dfs_access_in_type
PARAMS ((tree
, void *));
121 static access_kind access_in_type
PARAMS ((tree
, tree
));
122 static tree dfs_canonical_queue
PARAMS ((tree
, void *));
123 static tree dfs_assert_unmarked_p
PARAMS ((tree
, void *));
124 static void assert_canonical_unmarked
PARAMS ((tree
));
125 static int protected_accessible_p
PARAMS ((tree
, tree
, tree
));
126 static int friend_accessible_p
PARAMS ((tree
, tree
, tree
));
127 static void setup_class_bindings
PARAMS ((tree
, int));
128 static int template_self_reference_p
PARAMS ((tree
, tree
));
129 static tree dfs_find_vbase_instance
PARAMS ((tree
, void *));
130 static tree dfs_get_pure_virtuals
PARAMS ((tree
, void *));
131 static tree dfs_build_inheritance_graph_order
PARAMS ((tree
, void *));
133 /* Allocate a level of searching. */
135 static struct search_level
*
136 push_search_level (stack
, obstack
)
137 struct stack_level
*stack
;
138 struct obstack
*obstack
;
140 struct search_level tem
;
143 return push_stack_level (obstack
, (char *)&tem
, sizeof (tem
));
146 /* Discard a level of search allocation. */
148 static struct search_level
*
149 pop_search_level (obstack
)
150 struct stack_level
*obstack
;
152 register struct search_level
*stack
= pop_stack_level (obstack
);
157 /* Variables for gathering statistics. */
158 #ifdef GATHER_STATISTICS
159 static int n_fields_searched
;
160 static int n_calls_lookup_field
, n_calls_lookup_field_1
;
161 static int n_calls_lookup_fnfields
, n_calls_lookup_fnfields_1
;
162 static int n_calls_get_base_type
;
163 static int n_outer_fields_searched
;
164 static int n_contexts_saved
;
165 #endif /* GATHER_STATISTICS */
168 /* Worker for lookup_base. BINFO is the binfo we are searching at,
169 BASE is the RECORD_TYPE we are searching for. ACCESS is the
170 required access checks. WITHIN_CURRENT_SCOPE, IS_NON_PUBLIC and
171 IS_VIRTUAL indicate how BINFO was reached from the start of the
172 search. WITHIN_CURRENT_SCOPE is true if we met the current scope,
173 or friend thereof (this allows us to determine whether a protected
174 base is accessible or not). IS_NON_PUBLIC indicates whether BINFO
175 is accessible and IS_VIRTUAL indicates if it is morally virtual.
177 If BINFO is of the required type, then *BINFO_PTR is examined to
178 compare with any other instance of BASE we might have already
179 discovered. *BINFO_PTR is initialized and a base_kind return value
180 indicates what kind of base was located.
182 Otherwise BINFO's bases are searched. */
185 lookup_base_r (binfo
, base
, access
, within_current_scope
,
186 is_non_public
, is_virtual
, binfo_ptr
)
189 int within_current_scope
;
190 int is_non_public
; /* inside a non-public part */
191 int is_virtual
; /* inside a virtual part */
196 base_kind found
= bk_not_base
;
198 if (access
== ba_check
199 && !within_current_scope
200 && is_friend (BINFO_TYPE (binfo
), current_scope ()))
202 /* Do not clear is_non_public here. If A is a private base of B, A
203 is not allowed to convert a B* to an A*. */
204 within_current_scope
= 1;
207 if (same_type_p (BINFO_TYPE (binfo
), base
))
209 /* We have found a base. Check against what we have found
211 found
= bk_same_type
;
213 found
= bk_via_virtual
;
215 found
= bk_inaccessible
;
219 else if (!is_virtual
|| !tree_int_cst_equal (BINFO_OFFSET (binfo
),
220 BINFO_OFFSET (*binfo_ptr
)))
222 if (access
!= ba_any
)
224 else if (!is_virtual
)
225 /* Prefer a non-virtual base. */
233 bases
= BINFO_BASETYPES (binfo
);
237 for (i
= TREE_VEC_LENGTH (bases
); i
--;)
239 tree base_binfo
= TREE_VEC_ELT (bases
, i
);
240 int this_non_public
= is_non_public
;
241 int this_virtual
= is_virtual
;
244 if (access
<= ba_ignore
)
246 else if (TREE_VIA_PUBLIC (base_binfo
))
248 else if (access
== ba_not_special
)
250 else if (TREE_VIA_PROTECTED (base_binfo
) && within_current_scope
)
252 else if (is_friend (BINFO_TYPE (binfo
), current_scope ()))
257 if (TREE_VIA_VIRTUAL (base_binfo
))
260 bk
= lookup_base_r (base_binfo
, base
,
261 access
, within_current_scope
,
262 this_non_public
, this_virtual
,
268 if (access
!= ba_any
)
273 case bk_inaccessible
:
274 if (found
== bk_not_base
)
276 my_friendly_assert (found
== bk_via_virtual
277 || found
== bk_inaccessible
, 20010723);
285 my_friendly_assert (found
== bk_not_base
, 20010723);
290 if (found
!= bk_ambig
)
301 /* Lookup BASE in the hierarchy dominated by T. Do access checking as
302 ACCESS specifies. Return the binfo we discover (which might not be
303 canonical). If KIND_PTR is non-NULL, fill with information about
304 what kind of base we discovered.
306 If ba_quiet bit is set in ACCESS, then do not issue an error, and
307 return NULL_TREE for failure. */
310 lookup_base (t
, base
, access
, kind_ptr
)
315 tree binfo
= NULL
; /* The binfo we've found so far. */
318 if (t
== error_mark_node
|| base
== error_mark_node
)
321 *kind_ptr
= bk_not_base
;
322 return error_mark_node
;
324 my_friendly_assert (TYPE_P (t
) && TYPE_P (base
), 20011127);
326 /* Ensure that the types are instantiated. */
327 t
= complete_type (TYPE_MAIN_VARIANT (t
));
328 base
= complete_type (TYPE_MAIN_VARIANT (base
));
330 bk
= lookup_base_r (TYPE_BINFO (t
), base
, access
& ~ba_quiet
,
335 case bk_inaccessible
:
337 if (!(access
& ba_quiet
))
339 error ("`%T' is an inaccessible base of `%T'", base
, t
);
340 binfo
= error_mark_node
;
344 if (access
!= ba_any
)
347 if (!(access
& ba_quiet
))
349 error ("`%T' is an ambiguous base of `%T'", base
, t
);
350 binfo
= error_mark_node
;
363 /* Worker function for get_dynamic_cast_base_type. */
366 dynamic_cast_base_recurse (subtype
, binfo
, via_virtual
, offset_ptr
)
376 if (BINFO_TYPE (binfo
) == subtype
)
382 *offset_ptr
= BINFO_OFFSET (binfo
);
387 binfos
= BINFO_BASETYPES (binfo
);
388 n_baselinks
= binfos
? TREE_VEC_LENGTH (binfos
) : 0;
389 for (i
= 0; i
< n_baselinks
; i
++)
391 tree base_binfo
= TREE_VEC_ELT (binfos
, i
);
394 if (!TREE_VIA_PUBLIC (base_binfo
))
396 rval
= dynamic_cast_base_recurse
397 (subtype
, base_binfo
,
398 via_virtual
|| TREE_VIA_VIRTUAL (base_binfo
), offset_ptr
);
402 worst
= worst
>= 0 ? -3 : worst
;
405 else if (rval
== -3 && worst
!= -1)
411 /* The dynamic cast runtime needs a hint about how the static SUBTYPE type
412 started from is related to the required TARGET type, in order to optimize
413 the inheritance graph search. This information is independent of the
414 current context, and ignores private paths, hence get_base_distance is
415 inappropriate. Return a TREE specifying the base offset, BOFF.
416 BOFF >= 0, there is only one public non-virtual SUBTYPE base at offset BOFF,
417 and there are no public virtual SUBTYPE bases.
418 BOFF == -1, SUBTYPE occurs as multiple public virtual or non-virtual bases.
419 BOFF == -2, SUBTYPE is not a public base.
420 BOFF == -3, SUBTYPE occurs as multiple public non-virtual bases. */
423 get_dynamic_cast_base_type (subtype
, target
)
427 tree offset
= NULL_TREE
;
428 int boff
= dynamic_cast_base_recurse (subtype
, TYPE_BINFO (target
),
433 offset
= build_int_2 (boff
, -1);
434 TREE_TYPE (offset
) = ssizetype
;
438 /* Search for a member with name NAME in a multiple inheritance lattice
439 specified by TYPE. If it does not exist, return NULL_TREE.
440 If the member is ambiguously referenced, return `error_mark_node'.
441 Otherwise, return the FIELD_DECL. */
443 /* Do a 1-level search for NAME as a member of TYPE. The caller must
444 figure out whether it can access this field. (Since it is only one
445 level, this is reasonable.) */
448 lookup_field_1 (type
, name
)
453 if (TREE_CODE (type
) == TEMPLATE_TYPE_PARM
454 || TREE_CODE (type
) == BOUND_TEMPLATE_TEMPLATE_PARM
455 || TREE_CODE (type
) == TYPENAME_TYPE
)
456 /* The TYPE_FIELDS of a TEMPLATE_TYPE_PARM and
457 BOUND_TEMPLATE_TEMPLATE_PARM are not fields at all;
458 instead TYPE_FIELDS is the TEMPLATE_PARM_INDEX. (Miraculously,
459 the code often worked even when we treated the index as a list
461 The TYPE_FIELDS of TYPENAME_TYPE is its TYPENAME_TYPE_FULLNAME. */
465 && DECL_LANG_SPECIFIC (TYPE_NAME (type
))
466 && DECL_SORTED_FIELDS (TYPE_NAME (type
)))
468 tree
*fields
= &TREE_VEC_ELT (DECL_SORTED_FIELDS (TYPE_NAME (type
)), 0);
469 int lo
= 0, hi
= TREE_VEC_LENGTH (DECL_SORTED_FIELDS (TYPE_NAME (type
)));
476 #ifdef GATHER_STATISTICS
478 #endif /* GATHER_STATISTICS */
480 if (DECL_NAME (fields
[i
]) > name
)
482 else if (DECL_NAME (fields
[i
]) < name
)
486 /* We might have a nested class and a field with the
487 same name; we sorted them appropriately via
488 field_decl_cmp, so just look for the last field with
491 && DECL_NAME (fields
[i
+1]) == name
)
499 field
= TYPE_FIELDS (type
);
501 #ifdef GATHER_STATISTICS
502 n_calls_lookup_field_1
++;
503 #endif /* GATHER_STATISTICS */
506 #ifdef GATHER_STATISTICS
508 #endif /* GATHER_STATISTICS */
509 my_friendly_assert (DECL_P (field
), 0);
510 if (DECL_NAME (field
) == NULL_TREE
511 && ANON_AGGR_TYPE_P (TREE_TYPE (field
)))
513 tree temp
= lookup_field_1 (TREE_TYPE (field
), name
);
517 if (TREE_CODE (field
) == USING_DECL
)
518 /* For now, we're just treating member using declarations as
519 old ARM-style access declarations. Thus, there's no reason
520 to return a USING_DECL, and the rest of the compiler can't
521 handle it. Once the class is defined, these are purged
522 from TYPE_FIELDS anyhow; see handle_using_decl. */
524 else if (DECL_NAME (field
) == name
)
526 field
= TREE_CHAIN (field
);
529 if (name
== vptr_identifier
)
531 /* Give the user what s/he thinks s/he wants. */
532 if (TYPE_POLYMORPHIC_P (type
))
533 return TYPE_VFIELD (type
);
538 /* There are a number of cases we need to be aware of here:
539 current_class_type current_function_decl
546 Those last two make life interesting. If we're in a function which is
547 itself inside a class, we need decls to go into the fn's decls (our
548 second case below). But if we're in a class and the class itself is
549 inside a function, we need decls to go into the decls for the class. To
550 achieve this last goal, we must see if, when both current_class_ptr and
551 current_function_decl are set, the class was declared inside that
552 function. If so, we know to put the decls into the class's scope. */
557 if (current_function_decl
== NULL_TREE
)
558 return current_class_type
;
559 if (current_class_type
== NULL_TREE
)
560 return current_function_decl
;
561 if ((DECL_FUNCTION_MEMBER_P (current_function_decl
)
562 && same_type_p (DECL_CONTEXT (current_function_decl
),
564 || (DECL_FRIEND_CONTEXT (current_function_decl
)
565 && same_type_p (DECL_FRIEND_CONTEXT (current_function_decl
),
566 current_class_type
)))
567 return current_function_decl
;
569 return current_class_type
;
572 /* Returns non-zero if we are currently in a function scope. Note
573 that this function returns zero if we are within a local class, but
574 not within a member function body of the local class. */
577 at_function_scope_p ()
579 tree cs
= current_scope ();
580 return cs
&& TREE_CODE (cs
) == FUNCTION_DECL
;
583 /* Return the scope of DECL, as appropriate when doing name-lookup. */
586 context_for_name_lookup (decl
)
591 For the purposes of name lookup, after the anonymous union
592 definition, the members of the anonymous union are considered to
593 have been defined in the scope in which the anonymous union is
595 tree context
= DECL_CONTEXT (decl
);
597 while (context
&& TYPE_P (context
) && ANON_AGGR_TYPE_P (context
))
598 context
= TYPE_CONTEXT (context
);
600 context
= global_namespace
;
605 /* Return a canonical BINFO if BINFO is a virtual base, or just BINFO
609 canonical_binfo (binfo
)
612 return (TREE_VIA_VIRTUAL (binfo
)
613 ? TYPE_BINFO (BINFO_TYPE (binfo
)) : binfo
);
616 /* A queue function that simply ensures that we walk into the
617 canonical versions of virtual bases. */
620 dfs_canonical_queue (binfo
, data
)
622 void *data ATTRIBUTE_UNUSED
;
624 return canonical_binfo (binfo
);
627 /* Called via dfs_walk from assert_canonical_unmarked. */
630 dfs_assert_unmarked_p (binfo
, data
)
632 void *data ATTRIBUTE_UNUSED
;
634 my_friendly_assert (!BINFO_MARKED (binfo
), 0);
638 /* Asserts that all the nodes below BINFO (using the canonical
639 versions of virtual bases) are unmarked. */
642 assert_canonical_unmarked (binfo
)
645 dfs_walk (binfo
, dfs_assert_unmarked_p
, dfs_canonical_queue
, 0);
648 /* If BINFO is marked, return a canonical version of BINFO.
649 Otherwise, return NULL_TREE. */
652 shared_marked_p (binfo
, data
)
656 binfo
= canonical_binfo (binfo
);
657 return markedp (binfo
, data
);
660 /* If BINFO is not marked, return a canonical version of BINFO.
661 Otherwise, return NULL_TREE. */
664 shared_unmarked_p (binfo
, data
)
668 binfo
= canonical_binfo (binfo
);
669 return unmarkedp (binfo
, data
);
672 /* The accessibility routines use BINFO_ACCESS for scratch space
673 during the computation of the accssibility of some declaration. */
675 #define BINFO_ACCESS(NODE) \
676 ((access_kind) ((TREE_LANG_FLAG_1 (NODE) << 1) | TREE_LANG_FLAG_6 (NODE)))
678 /* Set the access associated with NODE to ACCESS. */
680 #define SET_BINFO_ACCESS(NODE, ACCESS) \
681 ((TREE_LANG_FLAG_1 (NODE) = ((ACCESS) & 2) != 0), \
682 (TREE_LANG_FLAG_6 (NODE) = ((ACCESS) & 1) != 0))
684 /* Called from access_in_type via dfs_walk. Calculate the access to
685 DATA (which is really a DECL) in BINFO. */
688 dfs_access_in_type (binfo
, data
)
692 tree decl
= (tree
) data
;
693 tree type
= BINFO_TYPE (binfo
);
694 access_kind access
= ak_none
;
696 if (context_for_name_lookup (decl
) == type
)
698 /* If we have desceneded to the scope of DECL, just note the
699 appropriate access. */
700 if (TREE_PRIVATE (decl
))
702 else if (TREE_PROTECTED (decl
))
703 access
= ak_protected
;
709 /* First, check for an access-declaration that gives us more
710 access to the DECL. The CONST_DECL for an enumeration
711 constant will not have DECL_LANG_SPECIFIC, and thus no
713 if (DECL_LANG_SPECIFIC (decl
) && !DECL_DISCRIMINATOR_P (decl
))
715 tree decl_access
= purpose_member (type
, DECL_ACCESS (decl
));
717 access
= ((access_kind
)
718 TREE_INT_CST_LOW (TREE_VALUE (decl_access
)));
727 /* Otherwise, scan our baseclasses, and pick the most favorable
729 binfos
= BINFO_BASETYPES (binfo
);
730 n_baselinks
= binfos
? TREE_VEC_LENGTH (binfos
) : 0;
731 for (i
= 0; i
< n_baselinks
; ++i
)
733 tree base_binfo
= TREE_VEC_ELT (binfos
, i
);
734 access_kind base_access
735 = BINFO_ACCESS (canonical_binfo (base_binfo
));
737 if (base_access
== ak_none
|| base_access
== ak_private
)
738 /* If it was not accessible in the base, or only
739 accessible as a private member, we can't access it
741 base_access
= ak_none
;
742 else if (TREE_VIA_PROTECTED (base_binfo
))
743 /* Public and protected members in the base are
745 base_access
= ak_protected
;
746 else if (!TREE_VIA_PUBLIC (base_binfo
))
747 /* Public and protected members in the base are
749 base_access
= ak_private
;
751 /* See if the new access, via this base, gives more
752 access than our previous best access. */
753 if (base_access
!= ak_none
754 && (base_access
== ak_public
755 || (base_access
== ak_protected
756 && access
!= ak_public
)
757 || (base_access
== ak_private
758 && access
== ak_none
)))
760 access
= base_access
;
762 /* If the new access is public, we can't do better. */
763 if (access
== ak_public
)
770 /* Note the access to DECL in TYPE. */
771 SET_BINFO_ACCESS (binfo
, access
);
773 /* Mark TYPE as visited so that if we reach it again we do not
774 duplicate our efforts here. */
775 SET_BINFO_MARKED (binfo
);
780 /* Return the access to DECL in TYPE. */
783 access_in_type (type
, decl
)
787 tree binfo
= TYPE_BINFO (type
);
789 /* We must take into account
793 If a name can be reached by several paths through a multiple
794 inheritance graph, the access is that of the path that gives
797 The algorithm we use is to make a post-order depth-first traversal
798 of the base-class hierarchy. As we come up the tree, we annotate
799 each node with the most lenient access. */
800 dfs_walk_real (binfo
, 0, dfs_access_in_type
, shared_unmarked_p
, decl
);
801 dfs_walk (binfo
, dfs_unmark
, shared_marked_p
, 0);
802 assert_canonical_unmarked (binfo
);
804 return BINFO_ACCESS (binfo
);
807 /* Called from dfs_accessible_p via dfs_walk. */
810 dfs_accessible_queue_p (binfo
, data
)
812 void *data ATTRIBUTE_UNUSED
;
814 if (BINFO_MARKED (binfo
))
817 /* If this class is inherited via private or protected inheritance,
818 then we can't see it, unless we are a friend of the subclass. */
819 if (!TREE_VIA_PUBLIC (binfo
)
820 && !is_friend (BINFO_TYPE (BINFO_INHERITANCE_CHAIN (binfo
)),
824 return canonical_binfo (binfo
);
827 /* Called from dfs_accessible_p via dfs_walk. */
830 dfs_accessible_p (binfo
, data
)
834 int protected_ok
= data
!= 0;
837 SET_BINFO_MARKED (binfo
);
838 access
= BINFO_ACCESS (binfo
);
839 if (access
== ak_public
|| (access
== ak_protected
&& protected_ok
))
841 else if (access
!= ak_none
842 && is_friend (BINFO_TYPE (binfo
), current_scope ()))
848 /* Returns non-zero if it is OK to access DECL through an object
849 indiated by BINFO in the context of DERIVED. */
852 protected_accessible_p (decl
, derived
, binfo
)
859 /* We're checking this clause from [class.access.base]
861 m as a member of N is protected, and the reference occurs in a
862 member or friend of class N, or in a member or friend of a
863 class P derived from N, where m as a member of P is private or
866 Here DERIVED is a possible P and DECL is m. accessible_p will
867 iterate over various values of N, but the access to m in DERIVED
870 Note that I believe that the passage above is wrong, and should read
871 "...is private or protected or public"; otherwise you get bizarre results
872 whereby a public using-decl can prevent you from accessing a protected
873 member of a base. (jason 2000/02/28) */
875 /* If DERIVED isn't derived from m's class, then it can't be a P. */
876 if (!DERIVED_FROM_P (context_for_name_lookup (decl
), derived
))
879 access
= access_in_type (derived
, decl
);
881 /* If m is inaccessible in DERIVED, then it's not a P. */
882 if (access
== ak_none
)
887 When a friend or a member function of a derived class references
888 a protected nonstatic member of a base class, an access check
889 applies in addition to those described earlier in clause
890 _class.access_) Except when forming a pointer to member
891 (_expr.unary.op_), the access must be through a pointer to,
892 reference to, or object of the derived class itself (or any class
893 derived from that class) (_expr.ref_). If the access is to form
894 a pointer to member, the nested-name-specifier shall name the
895 derived class (or any class derived from that class). */
896 if (DECL_NONSTATIC_MEMBER_P (decl
))
898 /* We can tell through what the reference is occurring by
899 chasing BINFO up to the root. */
901 while (BINFO_INHERITANCE_CHAIN (t
))
902 t
= BINFO_INHERITANCE_CHAIN (t
);
904 if (!DERIVED_FROM_P (derived
, BINFO_TYPE (t
)))
911 /* Returns non-zero if SCOPE is a friend of a type which would be able
912 to access DECL through the object indicated by BINFO. */
915 friend_accessible_p (scope
, decl
, binfo
)
920 tree befriending_classes
;
926 if (TREE_CODE (scope
) == FUNCTION_DECL
927 || DECL_FUNCTION_TEMPLATE_P (scope
))
928 befriending_classes
= DECL_BEFRIENDING_CLASSES (scope
);
929 else if (TYPE_P (scope
))
930 befriending_classes
= CLASSTYPE_BEFRIENDING_CLASSES (scope
);
934 for (t
= befriending_classes
; t
; t
= TREE_CHAIN (t
))
935 if (protected_accessible_p (decl
, TREE_VALUE (t
), binfo
))
938 /* Nested classes are implicitly friends of their enclosing types, as
939 per core issue 45 (this is a change from the standard). */
941 for (t
= TYPE_CONTEXT (scope
); t
&& TYPE_P (t
); t
= TYPE_CONTEXT (t
))
942 if (protected_accessible_p (decl
, t
, binfo
))
945 if (TREE_CODE (scope
) == FUNCTION_DECL
946 || DECL_FUNCTION_TEMPLATE_P (scope
))
948 /* Perhaps this SCOPE is a member of a class which is a
950 if (DECL_CLASS_SCOPE_P (decl
)
951 && friend_accessible_p (DECL_CONTEXT (scope
), decl
, binfo
))
954 /* Or an instantiation of something which is a friend. */
955 if (DECL_TEMPLATE_INFO (scope
))
956 return friend_accessible_p (DECL_TI_TEMPLATE (scope
), decl
, binfo
);
958 else if (CLASSTYPE_TEMPLATE_INFO (scope
))
959 return friend_accessible_p (CLASSTYPE_TI_TEMPLATE (scope
), decl
, binfo
);
964 /* Perform access control on TYPE_DECL VAL, which was looked up in TYPE.
965 This is fairly complex, so here's the design:
967 The lang_extdef nonterminal sets type_lookups to NULL_TREE before we
968 start to process a top-level declaration.
969 As we process the decl-specifier-seq for the declaration, any types we
970 see that might need access control are passed to type_access_control,
971 which defers checking by adding them to type_lookups.
972 When we are done with the decl-specifier-seq, we record the lookups we've
973 seen in the lookups field of the typed_declspecs nonterminal.
974 When we process the first declarator, either in parse_decl or
975 begin_function_definition, we call save_type_access_control,
976 which stores the lookups from the decl-specifier-seq in
977 current_type_lookups.
978 As we finish with each declarator, we process everything in type_lookups
979 via decl_type_access_control, which resets type_lookups to the value of
980 current_type_lookups for subsequent declarators.
981 When we enter a function, we set type_lookups to error_mark_node, so all
982 lookups are processed immediately. */
985 type_access_control (type
, val
)
988 if (val
== NULL_TREE
|| TREE_CODE (val
) != TYPE_DECL
989 || ! DECL_CLASS_SCOPE_P (val
))
992 if (type_lookups
== error_mark_node
)
993 enforce_access (type
, val
);
994 else if (! accessible_p (type
, val
))
995 type_lookups
= tree_cons (type
, val
, type_lookups
);
998 /* DECL is a declaration from a base class of TYPE, which was the
999 class used to name DECL. Return non-zero if, in the current
1000 context, DECL is accessible. If TYPE is actually a BINFO node,
1001 then we can tell in what context the access is occurring by looking
1002 at the most derived class along the path indicated by BINFO. */
1005 accessible_p (type
, decl
)
1013 /* Non-zero if it's OK to access DECL if it has protected
1014 accessibility in TYPE. */
1015 int protected_ok
= 0;
1017 /* If we're not checking access, everything is accessible. */
1018 if (!flag_access_control
)
1021 /* If this declaration is in a block or namespace scope, there's no
1023 if (!TYPE_P (context_for_name_lookup (decl
)))
1029 type
= BINFO_TYPE (type
);
1032 binfo
= TYPE_BINFO (type
);
1034 /* [class.access.base]
1036 A member m is accessible when named in class N if
1038 --m as a member of N is public, or
1040 --m as a member of N is private, and the reference occurs in a
1041 member or friend of class N, or
1043 --m as a member of N is protected, and the reference occurs in a
1044 member or friend of class N, or in a member or friend of a
1045 class P derived from N, where m as a member of P is private or
1048 --there exists a base class B of N that is accessible at the point
1049 of reference, and m is accessible when named in class B.
1051 We walk the base class hierarchy, checking these conditions. */
1053 /* Figure out where the reference is occurring. Check to see if
1054 DECL is private or protected in this scope, since that will
1055 determine whether protected access is allowed. */
1056 if (current_class_type
)
1057 protected_ok
= protected_accessible_p (decl
, current_class_type
, binfo
);
1059 /* Now, loop through the classes of which we are a friend. */
1061 protected_ok
= friend_accessible_p (current_scope (), decl
, binfo
);
1063 /* Standardize the binfo that access_in_type will use. We don't
1064 need to know what path was chosen from this point onwards. */
1065 binfo
= TYPE_BINFO (type
);
1067 /* Compute the accessibility of DECL in the class hierarchy
1068 dominated by type. */
1069 access_in_type (type
, decl
);
1070 /* Walk the hierarchy again, looking for a base class that allows
1072 t
= dfs_walk (binfo
, dfs_accessible_p
,
1073 dfs_accessible_queue_p
,
1074 protected_ok
? &protected_ok
: 0);
1075 /* Clear any mark bits. Note that we have to walk the whole tree
1076 here, since we have aborted the previous walk from some point
1077 deep in the tree. */
1078 dfs_walk (binfo
, dfs_unmark
, dfs_canonical_queue
, 0);
1079 assert_canonical_unmarked (binfo
);
1081 return t
!= NULL_TREE
;
1084 /* Routine to see if the sub-object denoted by the binfo PARENT can be
1085 found as a base class and sub-object of the object denoted by
1086 BINFO. MOST_DERIVED is the most derived type of the hierarchy being
1090 is_subobject_of_p (parent
, binfo
, most_derived
)
1091 tree parent
, binfo
, most_derived
;
1096 if (parent
== binfo
)
1099 binfos
= BINFO_BASETYPES (binfo
);
1100 n_baselinks
= binfos
? TREE_VEC_LENGTH (binfos
) : 0;
1102 /* Iterate the base types. */
1103 for (i
= 0; i
< n_baselinks
; i
++)
1105 tree base_binfo
= TREE_VEC_ELT (binfos
, i
);
1106 if (!CLASS_TYPE_P (TREE_TYPE (base_binfo
)))
1107 /* If we see a TEMPLATE_TYPE_PARM, or some such, as a base
1108 class there's no way to descend into it. */
1111 if (is_subobject_of_p (parent
,
1112 CANONICAL_BINFO (base_binfo
, most_derived
),
1119 struct lookup_field_info
{
1120 /* The type in which we're looking. */
1122 /* The name of the field for which we're looking. */
1124 /* If non-NULL, the current result of the lookup. */
1126 /* The path to RVAL. */
1128 /* If non-NULL, the lookup was ambiguous, and this is a list of the
1131 /* If non-zero, we are looking for types, not data members. */
1133 /* If non-zero, RVAL was found by looking through a dependent base. */
1134 int from_dep_base_p
;
1135 /* If something went wrong, a message indicating what. */
1139 /* Returns non-zero if BINFO is not hidden by the value found by the
1140 lookup so far. If BINFO is hidden, then there's no need to look in
1141 it. DATA is really a struct lookup_field_info. Called from
1142 lookup_field via breadth_first_search. */
1145 lookup_field_queue_p (binfo
, data
)
1149 struct lookup_field_info
*lfi
= (struct lookup_field_info
*) data
;
1151 /* Don't look for constructors or destructors in base classes. */
1152 if (IDENTIFIER_CTOR_OR_DTOR_P (lfi
->name
))
1155 /* If this base class is hidden by the best-known value so far, we
1156 don't need to look. */
1157 if (!lfi
->from_dep_base_p
&& lfi
->rval_binfo
1158 && is_subobject_of_p (binfo
, lfi
->rval_binfo
, lfi
->type
))
1161 return CANONICAL_BINFO (binfo
, lfi
->type
);
1164 /* Within the scope of a template class, you can refer to the to the
1165 current specialization with the name of the template itself. For
1168 template <typename T> struct S { S* sp; }
1170 Returns non-zero if DECL is such a declaration in a class TYPE. */
1173 template_self_reference_p (type
, decl
)
1177 return (CLASSTYPE_USE_TEMPLATE (type
)
1178 && PRIMARY_TEMPLATE_P (CLASSTYPE_TI_TEMPLATE (type
))
1179 && TREE_CODE (decl
) == TYPE_DECL
1180 && DECL_ARTIFICIAL (decl
)
1181 && DECL_NAME (decl
) == constructor_name (type
));
1185 /* Nonzero for a class member means that it is shared between all objects
1188 [class.member.lookup]:If the resulting set of declarations are not all
1189 from sub-objects of the same type, or the set has a nonstatic member
1190 and includes members from distinct sub-objects, there is an ambiguity
1191 and the program is ill-formed.
1193 This function checks that T contains no nonstatic members. */
1199 if (TREE_CODE (t
) == VAR_DECL
|| TREE_CODE (t
) == TYPE_DECL \
1200 || TREE_CODE (t
) == CONST_DECL
)
1202 if (is_overloaded_fn (t
))
1204 for (; t
; t
= OVL_NEXT (t
))
1206 tree fn
= OVL_CURRENT (t
);
1207 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (fn
))
1215 /* DATA is really a struct lookup_field_info. Look for a field with
1216 the name indicated there in BINFO. If this function returns a
1217 non-NULL value it is the result of the lookup. Called from
1218 lookup_field via breadth_first_search. */
1221 lookup_field_r (binfo
, data
)
1225 struct lookup_field_info
*lfi
= (struct lookup_field_info
*) data
;
1226 tree type
= BINFO_TYPE (binfo
);
1227 tree nval
= NULL_TREE
;
1228 int from_dep_base_p
;
1230 /* First, look for a function. There can't be a function and a data
1231 member with the same name, and if there's a function and a type
1232 with the same name, the type is hidden by the function. */
1233 if (!lfi
->want_type
)
1235 int idx
= lookup_fnfields_1 (type
, lfi
->name
);
1237 nval
= TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (type
), idx
);
1241 /* Look for a data member or type. */
1242 nval
= lookup_field_1 (type
, lfi
->name
);
1244 /* If there is no declaration with the indicated name in this type,
1245 then there's nothing to do. */
1249 /* If we're looking up a type (as with an elaborated type specifier)
1250 we ignore all non-types we find. */
1251 if (lfi
->want_type
&& TREE_CODE (nval
) != TYPE_DECL
1252 && !DECL_CLASS_TEMPLATE_P (nval
))
1254 if (lfi
->name
== TYPE_IDENTIFIER (type
))
1256 /* If the aggregate has no user defined constructors, we allow
1257 it to have fields with the same name as the enclosing type.
1258 If we are looking for that name, find the corresponding
1260 for (nval
= TREE_CHAIN (nval
); nval
; nval
= TREE_CHAIN (nval
))
1261 if (DECL_NAME (nval
) == lfi
->name
1262 && TREE_CODE (nval
) == TYPE_DECL
)
1269 nval
= purpose_member (lfi
->name
, CLASSTYPE_TAGS (type
));
1271 nval
= TYPE_MAIN_DECL (TREE_VALUE (nval
));
1277 /* You must name a template base class with a template-id. */
1278 if (!same_type_p (type
, lfi
->type
)
1279 && template_self_reference_p (type
, nval
))
1282 from_dep_base_p
= dependent_base_p (binfo
);
1283 if (lfi
->from_dep_base_p
&& !from_dep_base_p
)
1285 /* If the new declaration is not found via a dependent base, and
1286 the old one was, then we must prefer the new one. We weren't
1287 really supposed to be able to find the old one, so we don't
1288 want to be affected by a specialization. Consider:
1290 struct B { typedef int I; };
1291 template <typename T> struct D1 : virtual public B {};
1292 template <typename T> struct D :
1293 public D1, virtual pubic B { I i; };
1295 The `I' in `D<T>' is unambigousuly `B::I', regardless of how
1296 D1 is specialized. */
1297 lfi
->from_dep_base_p
= 0;
1298 lfi
->rval
= NULL_TREE
;
1299 lfi
->rval_binfo
= NULL_TREE
;
1300 lfi
->ambiguous
= NULL_TREE
;
1303 else if (lfi
->rval_binfo
&& !lfi
->from_dep_base_p
&& from_dep_base_p
)
1304 /* Similarly, if the old declaration was not found via a dependent
1305 base, and the new one is, ignore the new one. */
1308 /* If the lookup already found a match, and the new value doesn't
1309 hide the old one, we might have an ambiguity. */
1310 if (lfi
->rval_binfo
&& !is_subobject_of_p (lfi
->rval_binfo
, binfo
, lfi
->type
))
1312 if (nval
== lfi
->rval
&& shared_member_p (nval
))
1313 /* The two things are really the same. */
1315 else if (is_subobject_of_p (binfo
, lfi
->rval_binfo
, lfi
->type
))
1316 /* The previous value hides the new one. */
1320 /* We have a real ambiguity. We keep a chain of all the
1322 if (!lfi
->ambiguous
&& lfi
->rval
)
1324 /* This is the first time we noticed an ambiguity. Add
1325 what we previously thought was a reasonable candidate
1327 lfi
->ambiguous
= tree_cons (NULL_TREE
, lfi
->rval
, NULL_TREE
);
1328 TREE_TYPE (lfi
->ambiguous
) = error_mark_node
;
1331 /* Add the new value. */
1332 lfi
->ambiguous
= tree_cons (NULL_TREE
, nval
, lfi
->ambiguous
);
1333 TREE_TYPE (lfi
->ambiguous
) = error_mark_node
;
1334 lfi
->errstr
= "request for member `%D' is ambiguous";
1339 if (from_dep_base_p
&& TREE_CODE (nval
) != TYPE_DECL
1340 /* We need to return a member template class so we can
1341 define partial specializations. Is there a better
1343 && !DECL_CLASS_TEMPLATE_P (nval
))
1344 /* The thing we're looking for isn't a type, so the implicit
1345 typename extension doesn't apply, so we just pretend we
1346 didn't find anything. */
1350 lfi
->from_dep_base_p
= from_dep_base_p
;
1351 lfi
->rval_binfo
= binfo
;
1357 /* Look for a member named NAME in an inheritance lattice dominated by
1358 XBASETYPE. If PROTECT is 0 or two, we do not check access. If it is
1359 1, we enforce accessibility. If PROTECT is zero, then, for an
1360 ambiguous lookup, we return NULL. If PROTECT is 1, we issue an
1361 error message. If PROTECT is 2, we return a TREE_LIST whose
1362 TREE_TYPE is error_mark_node and whose TREE_VALUEs are the list of
1363 ambiguous candidates.
1365 WANT_TYPE is 1 when we should only return TYPE_DECLs, if no
1366 TYPE_DECL can be found return NULL_TREE. */
1369 lookup_member (xbasetype
, name
, protect
, want_type
)
1370 register tree xbasetype
, name
;
1371 int protect
, want_type
;
1373 tree rval
, rval_binfo
= NULL_TREE
;
1374 tree type
= NULL_TREE
, basetype_path
= NULL_TREE
;
1375 struct lookup_field_info lfi
;
1377 /* rval_binfo is the binfo associated with the found member, note,
1378 this can be set with useful information, even when rval is not
1379 set, because it must deal with ALL members, not just non-function
1380 members. It is used for ambiguity checking and the hidden
1381 checks. Whereas rval is only set if a proper (not hidden)
1382 non-function member is found. */
1384 const char *errstr
= 0;
1386 if (xbasetype
== current_class_type
&& TYPE_BEING_DEFINED (xbasetype
)
1387 && IDENTIFIER_CLASS_VALUE (name
))
1389 tree field
= IDENTIFIER_CLASS_VALUE (name
);
1390 if (TREE_CODE (field
) != FUNCTION_DECL
1391 && ! (want_type
&& TREE_CODE (field
) != TYPE_DECL
))
1392 /* We're in the scope of this class, and the value has already
1393 been looked up. Just return the cached value. */
1397 if (TREE_CODE (xbasetype
) == TREE_VEC
)
1399 type
= BINFO_TYPE (xbasetype
);
1400 basetype_path
= xbasetype
;
1402 else if (IS_AGGR_TYPE_CODE (TREE_CODE (xbasetype
)))
1405 basetype_path
= TYPE_BINFO (type
);
1406 my_friendly_assert (BINFO_INHERITANCE_CHAIN (basetype_path
) == NULL_TREE
,
1412 complete_type (type
);
1414 #ifdef GATHER_STATISTICS
1415 n_calls_lookup_field
++;
1416 #endif /* GATHER_STATISTICS */
1418 memset ((PTR
) &lfi
, 0, sizeof (lfi
));
1421 lfi
.want_type
= want_type
;
1422 bfs_walk (basetype_path
, &lookup_field_r
, &lookup_field_queue_p
, &lfi
);
1424 rval_binfo
= lfi
.rval_binfo
;
1426 type
= BINFO_TYPE (rval_binfo
);
1427 errstr
= lfi
.errstr
;
1429 /* If we are not interested in ambiguities, don't report them;
1430 just return NULL_TREE. */
1431 if (!protect
&& lfi
.ambiguous
)
1437 return lfi
.ambiguous
;
1444 In the case of overloaded function names, access control is
1445 applied to the function selected by overloaded resolution. */
1446 if (rval
&& protect
&& !is_overloaded_fn (rval
)
1447 && !enforce_access (xbasetype
, rval
))
1448 return error_mark_node
;
1450 if (errstr
&& protect
)
1452 error (errstr
, name
, type
);
1454 print_candidates (lfi
.ambiguous
);
1455 rval
= error_mark_node
;
1458 /* If the thing we found was found via the implicit typename
1459 extension, build the typename type. */
1460 if (rval
&& lfi
.from_dep_base_p
&& !DECL_CLASS_TEMPLATE_P (rval
))
1461 rval
= TYPE_STUB_DECL (build_typename_type (BINFO_TYPE (basetype_path
),
1465 if (rval
&& is_overloaded_fn (rval
))
1467 /* Note that the binfo we put in the baselink is the binfo where
1468 we found the functions, which we need for overload
1469 resolution, but which should not be passed to enforce_access;
1470 rather, enforce_access wants a binfo which refers to the
1471 scope in which we started looking for the function. This
1472 will generally be the binfo passed into this function as
1475 rval
= tree_cons (rval_binfo
, rval
, NULL_TREE
);
1476 SET_BASELINK_P (rval
);
1482 /* Like lookup_member, except that if we find a function member we
1483 return NULL_TREE. */
1486 lookup_field (xbasetype
, name
, protect
, want_type
)
1487 register tree xbasetype
, name
;
1488 int protect
, want_type
;
1490 tree rval
= lookup_member (xbasetype
, name
, protect
, want_type
);
1492 /* Ignore functions. */
1493 if (rval
&& TREE_CODE (rval
) == TREE_LIST
)
1499 /* Like lookup_member, except that if we find a non-function member we
1500 return NULL_TREE. */
1503 lookup_fnfields (xbasetype
, name
, protect
)
1504 register tree xbasetype
, name
;
1507 tree rval
= lookup_member (xbasetype
, name
, protect
, /*want_type=*/0);
1509 /* Ignore non-functions. */
1510 if (rval
&& TREE_CODE (rval
) != TREE_LIST
)
1516 /* TYPE is a class type. Return the index of the fields within
1517 the method vector with name NAME, or -1 is no such field exists. */
1520 lookup_fnfields_1 (type
, name
)
1523 tree method_vec
= (CLASS_TYPE_P (type
)
1524 ? CLASSTYPE_METHOD_VEC (type
)
1527 if (method_vec
!= 0)
1530 register tree
*methods
= &TREE_VEC_ELT (method_vec
, 0);
1531 int len
= TREE_VEC_LENGTH (method_vec
);
1534 #ifdef GATHER_STATISTICS
1535 n_calls_lookup_fnfields_1
++;
1536 #endif /* GATHER_STATISTICS */
1538 /* Constructors are first... */
1539 if (name
== ctor_identifier
)
1540 return (methods
[CLASSTYPE_CONSTRUCTOR_SLOT
]
1541 ? CLASSTYPE_CONSTRUCTOR_SLOT
: -1);
1542 /* and destructors are second. */
1543 if (name
== dtor_identifier
)
1544 return (methods
[CLASSTYPE_DESTRUCTOR_SLOT
]
1545 ? CLASSTYPE_DESTRUCTOR_SLOT
: -1);
1547 for (i
= CLASSTYPE_FIRST_CONVERSION_SLOT
;
1548 i
< len
&& methods
[i
];
1551 #ifdef GATHER_STATISTICS
1552 n_outer_fields_searched
++;
1553 #endif /* GATHER_STATISTICS */
1555 tmp
= OVL_CURRENT (methods
[i
]);
1556 if (DECL_NAME (tmp
) == name
)
1559 /* If the type is complete and we're past the conversion ops,
1560 switch to binary search. */
1561 if (! DECL_CONV_FN_P (tmp
)
1562 && COMPLETE_TYPE_P (type
))
1564 int lo
= i
+ 1, hi
= len
;
1570 #ifdef GATHER_STATISTICS
1571 n_outer_fields_searched
++;
1572 #endif /* GATHER_STATISTICS */
1574 tmp
= DECL_NAME (OVL_CURRENT (methods
[i
]));
1578 else if (tmp
< name
)
1587 /* If we didn't find it, it might have been a template
1588 conversion operator to a templated type. If there are any,
1589 such template conversion operators will all be overloaded on
1590 the first conversion slot. (Note that we don't look for this
1591 case above so that we will always find specializations
1593 if (IDENTIFIER_TYPENAME_P (name
))
1595 i
= CLASSTYPE_FIRST_CONVERSION_SLOT
;
1596 if (i
< len
&& methods
[i
])
1598 tmp
= OVL_CURRENT (methods
[i
]);
1599 if (TREE_CODE (tmp
) == TEMPLATE_DECL
1600 && DECL_TEMPLATE_CONV_FN_P (tmp
))
1609 /* Walk the class hierarchy dominated by TYPE. FN is called for each
1610 type in the hierarchy, in a breadth-first preorder traversal.
1611 If it ever returns a non-NULL value, that value is immediately
1612 returned and the walk is terminated. At each node, FN is passed a
1613 BINFO indicating the path from the curently visited base-class to
1614 TYPE. Before each base-class is walked QFN is called. If the
1615 value returned is non-zero, the base-class is walked; otherwise it
1616 is not. If QFN is NULL, it is treated as a function which always
1617 returns 1. Both FN and QFN are passed the DATA whenever they are
1621 bfs_walk (binfo
, fn
, qfn
, data
)
1623 tree (*fn
) PARAMS ((tree
, void *));
1624 tree (*qfn
) PARAMS ((tree
, void *));
1629 tree rval
= NULL_TREE
;
1630 /* An array of the base classes of BINFO. These will be built up in
1631 breadth-first order, except where QFN prunes the search. */
1632 varray_type bfs_bases
;
1634 /* Start with enough room for ten base classes. That will be enough
1635 for most hierarchies. */
1636 VARRAY_TREE_INIT (bfs_bases
, 10, "search_stack");
1638 /* Put the first type into the stack. */
1639 VARRAY_TREE (bfs_bases
, 0) = binfo
;
1642 for (head
= 0; head
< tail
; ++head
)
1648 /* Pull the next type out of the queue. */
1649 binfo
= VARRAY_TREE (bfs_bases
, head
);
1651 /* If this is the one we're looking for, we're done. */
1652 rval
= (*fn
) (binfo
, data
);
1656 /* Queue up the base types. */
1657 binfos
= BINFO_BASETYPES (binfo
);
1658 n_baselinks
= binfos
? TREE_VEC_LENGTH (binfos
): 0;
1659 for (i
= 0; i
< n_baselinks
; i
++)
1661 tree base_binfo
= TREE_VEC_ELT (binfos
, i
);
1664 base_binfo
= (*qfn
) (base_binfo
, data
);
1668 if (tail
== VARRAY_SIZE (bfs_bases
))
1669 VARRAY_GROW (bfs_bases
, 2 * VARRAY_SIZE (bfs_bases
));
1670 VARRAY_TREE (bfs_bases
, tail
) = base_binfo
;
1677 VARRAY_FREE (bfs_bases
);
1682 /* Exactly like bfs_walk, except that a depth-first traversal is
1683 performed, and PREFN is called in preorder, while POSTFN is called
1687 dfs_walk_real (binfo
, prefn
, postfn
, qfn
, data
)
1689 tree (*prefn
) PARAMS ((tree
, void *));
1690 tree (*postfn
) PARAMS ((tree
, void *));
1691 tree (*qfn
) PARAMS ((tree
, void *));
1697 tree rval
= NULL_TREE
;
1699 /* Call the pre-order walking function. */
1702 rval
= (*prefn
) (binfo
, data
);
1707 /* Process the basetypes. */
1708 binfos
= BINFO_BASETYPES (binfo
);
1709 n_baselinks
= BINFO_N_BASETYPES (binfo
);
1710 for (i
= 0; i
< n_baselinks
; i
++)
1712 tree base_binfo
= TREE_VEC_ELT (binfos
, i
);
1715 base_binfo
= (*qfn
) (base_binfo
, data
);
1719 rval
= dfs_walk_real (base_binfo
, prefn
, postfn
, qfn
, data
);
1725 /* Call the post-order walking function. */
1727 rval
= (*postfn
) (binfo
, data
);
1732 /* Exactly like bfs_walk, except that a depth-first post-order traversal is
1736 dfs_walk (binfo
, fn
, qfn
, data
)
1738 tree (*fn
) PARAMS ((tree
, void *));
1739 tree (*qfn
) PARAMS ((tree
, void *));
1742 return dfs_walk_real (binfo
, 0, fn
, qfn
, data
);
1745 /* Returns > 0 if a function with type DRETTYPE overriding a function
1746 with type BRETTYPE is covariant, as defined in [class.virtual].
1748 Returns 1 if trivial covariance, 2 if non-trivial (requiring runtime
1749 adjustment), or -1 if pedantically invalid covariance. */
1752 covariant_return_p (brettype
, drettype
)
1753 tree brettype
, drettype
;
1758 if (TREE_CODE (brettype
) == FUNCTION_DECL
)
1760 brettype
= TREE_TYPE (TREE_TYPE (brettype
));
1761 drettype
= TREE_TYPE (TREE_TYPE (drettype
));
1763 else if (TREE_CODE (brettype
) == METHOD_TYPE
)
1765 brettype
= TREE_TYPE (brettype
);
1766 drettype
= TREE_TYPE (drettype
);
1769 if (same_type_p (brettype
, drettype
))
1772 if (! (TREE_CODE (brettype
) == TREE_CODE (drettype
)
1773 && (TREE_CODE (brettype
) == POINTER_TYPE
1774 || TREE_CODE (brettype
) == REFERENCE_TYPE
)
1775 && TYPE_QUALS (brettype
) == TYPE_QUALS (drettype
)))
1778 if (! can_convert (brettype
, drettype
))
1781 brettype
= TREE_TYPE (brettype
);
1782 drettype
= TREE_TYPE (drettype
);
1784 /* If not pedantic, allow any standard pointer conversion. */
1785 if (! IS_AGGR_TYPE (drettype
) || ! IS_AGGR_TYPE (brettype
))
1788 binfo
= lookup_base (drettype
, brettype
, ba_check
| ba_quiet
, &kind
);
1792 if (BINFO_OFFSET_ZEROP (binfo
) && kind
!= bk_via_virtual
)
1797 /* Check that virtual overrider OVERRIDER is acceptable for base function
1798 BASEFN. Issue diagnostic, and return zero, if unacceptable. */
1801 check_final_overrider (overrider
, basefn
)
1802 tree overrider
, basefn
;
1804 tree over_type
= TREE_TYPE (overrider
);
1805 tree base_type
= TREE_TYPE (basefn
);
1806 tree over_return
= TREE_TYPE (over_type
);
1807 tree base_return
= TREE_TYPE (base_type
);
1808 tree over_throw
= TYPE_RAISES_EXCEPTIONS (over_type
);
1809 tree base_throw
= TYPE_RAISES_EXCEPTIONS (base_type
);
1812 if (same_type_p (base_return
, over_return
))
1814 else if ((i
= covariant_return_p (base_return
, over_return
)))
1817 sorry ("adjusting pointers for covariant returns");
1819 if (pedantic
&& i
== -1)
1821 cp_pedwarn_at ("invalid covariant return type for `%#D'", overrider
);
1822 cp_pedwarn_at (" overriding `%#D' (must be pointer or reference to class)", basefn
);
1825 else if (IS_AGGR_TYPE_2 (base_return
, over_return
)
1826 && same_or_base_type_p (base_return
, over_return
))
1828 cp_error_at ("invalid covariant return type for `%#D'", overrider
);
1829 cp_error_at (" overriding `%#D' (must use pointer or reference)", basefn
);
1832 else if (IDENTIFIER_ERROR_LOCUS (DECL_ASSEMBLER_NAME (overrider
)) == NULL_TREE
)
1834 cp_error_at ("conflicting return type specified for `%#D'", overrider
);
1835 cp_error_at (" overriding `%#D'", basefn
);
1836 SET_IDENTIFIER_ERROR_LOCUS (DECL_ASSEMBLER_NAME (overrider
),
1837 DECL_CONTEXT (overrider
));
1841 /* Check throw specifier is at least as strict. */
1842 if (!comp_except_specs (base_throw
, over_throw
, 0))
1844 cp_error_at ("looser throw specifier for `%#F'", overrider
);
1845 cp_error_at (" overriding `%#F'", basefn
);
1851 /* Given a class TYPE, and a function decl FNDECL, look for
1852 virtual functions in TYPE's hierarchy which FNDECL overrides.
1853 We do not look in TYPE itself, only its bases.
1855 Returns non-zero, if we find any. Set FNDECL's DECL_VIRTUAL_P, if we
1856 find that it overrides anything.
1858 We check that every function which is overridden, is correctly
1862 look_for_overrides (type
, fndecl
)
1865 tree binfo
= TYPE_BINFO (type
);
1866 tree basebinfos
= BINFO_BASETYPES (binfo
);
1867 int nbasebinfos
= basebinfos
? TREE_VEC_LENGTH (basebinfos
) : 0;
1871 for (ix
= 0; ix
!= nbasebinfos
; ix
++)
1873 tree basetype
= BINFO_TYPE (TREE_VEC_ELT (basebinfos
, ix
));
1875 if (TYPE_POLYMORPHIC_P (basetype
))
1876 found
+= look_for_overrides_r (basetype
, fndecl
);
1881 /* Look in TYPE for virtual functions with the same signature as FNDECL.
1882 This differs from get_matching_virtual in that it will only return
1883 a function from TYPE. */
1886 look_for_overrides_here (type
, fndecl
)
1891 if (DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fndecl
))
1892 ix
= CLASSTYPE_DESTRUCTOR_SLOT
;
1894 ix
= lookup_fnfields_1 (type
, DECL_NAME (fndecl
));
1897 tree fns
= TREE_VEC_ELT (CLASSTYPE_METHOD_VEC (type
), ix
);
1899 for (; fns
; fns
= OVL_NEXT (fns
))
1901 tree fn
= OVL_CURRENT (fns
);
1903 if (!DECL_VIRTUAL_P (fn
))
1904 /* Not a virtual. */;
1905 else if (DECL_CONTEXT (fn
) != type
)
1906 /* Introduced with a using declaration. */;
1907 else if (DECL_STATIC_FUNCTION_P (fndecl
))
1909 tree btypes
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
1910 tree dtypes
= TYPE_ARG_TYPES (TREE_TYPE (fndecl
));
1911 if (compparms (TREE_CHAIN (btypes
), dtypes
))
1914 else if (same_signature_p (fndecl
, fn
))
1921 /* Look in TYPE for virtual functions overridden by FNDECL. Check both
1922 TYPE itself and its bases. */
1925 look_for_overrides_r (type
, fndecl
)
1928 tree fn
= look_for_overrides_here (type
, fndecl
);
1931 if (DECL_STATIC_FUNCTION_P (fndecl
))
1933 /* A static member function cannot match an inherited
1934 virtual member function. */
1935 cp_error_at ("`%#D' cannot be declared", fndecl
);
1936 cp_error_at (" since `%#D' declared in base class", fn
);
1940 /* It's definitely virtual, even if not explicitly set. */
1941 DECL_VIRTUAL_P (fndecl
) = 1;
1942 check_final_overrider (fndecl
, fn
);
1947 /* We failed to find one declared in this class. Look in its bases. */
1948 return look_for_overrides (type
, fndecl
);
1951 /* A queue function to use with dfs_walk that only walks into
1952 canonical bases. DATA should be the type of the complete object,
1953 or a TREE_LIST whose TREE_PURPOSE is the type of the complete
1954 object. By using this function as a queue function, you will walk
1955 over exactly those BINFOs that actually exist in the complete
1956 object, including those for virtual base classes. If you
1957 SET_BINFO_MARKED for each binfo you process, you are further
1958 guaranteed that you will walk into each virtual base class exactly
1962 dfs_unmarked_real_bases_queue_p (binfo
, data
)
1966 if (TREE_VIA_VIRTUAL (binfo
))
1968 tree type
= (tree
) data
;
1970 if (TREE_CODE (type
) == TREE_LIST
)
1971 type
= TREE_PURPOSE (type
);
1972 binfo
= binfo_for_vbase (BINFO_TYPE (binfo
), type
);
1974 return unmarkedp (binfo
, NULL
);
1977 /* Like dfs_unmarked_real_bases_queue_p but walks only into things
1978 that are marked, rather than unmarked. */
1981 dfs_marked_real_bases_queue_p (binfo
, data
)
1985 if (TREE_VIA_VIRTUAL (binfo
))
1987 tree type
= (tree
) data
;
1989 if (TREE_CODE (type
) == TREE_LIST
)
1990 type
= TREE_PURPOSE (type
);
1991 binfo
= binfo_for_vbase (BINFO_TYPE (binfo
), type
);
1993 return markedp (binfo
, NULL
);
1996 /* A queue function that skips all virtual bases (and their
2000 dfs_skip_vbases (binfo
, data
)
2002 void *data ATTRIBUTE_UNUSED
;
2004 if (TREE_VIA_VIRTUAL (binfo
))
2010 /* Called via dfs_walk from dfs_get_pure_virtuals. */
2013 dfs_get_pure_virtuals (binfo
, data
)
2017 tree type
= (tree
) data
;
2019 /* We're not interested in primary base classes; the derived class
2020 of which they are a primary base will contain the information we
2022 if (!BINFO_PRIMARY_P (binfo
))
2026 for (virtuals
= BINFO_VIRTUALS (binfo
);
2028 virtuals
= TREE_CHAIN (virtuals
))
2029 if (DECL_PURE_VIRTUAL_P (BV_FN (virtuals
)))
2030 CLASSTYPE_PURE_VIRTUALS (type
)
2031 = tree_cons (NULL_TREE
, BV_FN (virtuals
),
2032 CLASSTYPE_PURE_VIRTUALS (type
));
2035 SET_BINFO_MARKED (binfo
);
2040 /* Set CLASSTYPE_PURE_VIRTUALS for TYPE. */
2043 get_pure_virtuals (type
)
2048 /* Clear the CLASSTYPE_PURE_VIRTUALS list; whatever is already there
2049 is going to be overridden. */
2050 CLASSTYPE_PURE_VIRTUALS (type
) = NULL_TREE
;
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 (TYPE_BINFO (type
), dfs_get_pure_virtuals
,
2058 dfs_unmarked_real_bases_queue_p
, type
);
2059 dfs_walk (TYPE_BINFO (type
), dfs_unmark
,
2060 dfs_marked_real_bases_queue_p
, type
);
2062 /* Put the pure virtuals in dfs order. */
2063 CLASSTYPE_PURE_VIRTUALS (type
) = nreverse (CLASSTYPE_PURE_VIRTUALS (type
));
2065 for (vbases
= CLASSTYPE_VBASECLASSES (type
);
2067 vbases
= TREE_CHAIN (vbases
))
2071 for (virtuals
= BINFO_VIRTUALS (TREE_VALUE (vbases
));
2073 virtuals
= TREE_CHAIN (virtuals
))
2075 tree base_fndecl
= BV_FN (virtuals
);
2076 if (DECL_NEEDS_FINAL_OVERRIDER_P (base_fndecl
))
2077 error ("`%#D' needs a final overrider", base_fndecl
);
2082 /* DEPTH-FIRST SEARCH ROUTINES. */
2085 markedp (binfo
, data
)
2087 void *data ATTRIBUTE_UNUSED
;
2089 return BINFO_MARKED (binfo
) ? binfo
: NULL_TREE
;
2093 unmarkedp (binfo
, data
)
2095 void *data ATTRIBUTE_UNUSED
;
2097 return !BINFO_MARKED (binfo
) ? binfo
: NULL_TREE
;
2101 marked_vtable_pathp (binfo
, data
)
2103 void *data ATTRIBUTE_UNUSED
;
2105 return BINFO_VTABLE_PATH_MARKED (binfo
) ? binfo
: NULL_TREE
;
2109 unmarked_vtable_pathp (binfo
, data
)
2111 void *data ATTRIBUTE_UNUSED
;
2113 return !BINFO_VTABLE_PATH_MARKED (binfo
) ? binfo
: NULL_TREE
;
2117 marked_pushdecls_p (binfo
, data
)
2119 void *data ATTRIBUTE_UNUSED
;
2121 return (CLASS_TYPE_P (BINFO_TYPE (binfo
))
2122 && BINFO_PUSHDECLS_MARKED (binfo
)) ? binfo
: NULL_TREE
;
2126 unmarked_pushdecls_p (binfo
, data
)
2128 void *data ATTRIBUTE_UNUSED
;
2130 return (CLASS_TYPE_P (BINFO_TYPE (binfo
))
2131 && !BINFO_PUSHDECLS_MARKED (binfo
)) ? binfo
: NULL_TREE
;
2134 /* The worker functions for `dfs_walk'. These do not need to
2135 test anything (vis a vis marking) if they are paired with
2136 a predicate function (above). */
2139 dfs_unmark (binfo
, data
)
2141 void *data ATTRIBUTE_UNUSED
;
2143 CLEAR_BINFO_MARKED (binfo
);
2147 /* get virtual base class types.
2148 This adds type to the vbase_types list in reverse dfs order.
2149 Ordering is very important, so don't change it. */
2152 dfs_get_vbase_types (binfo
, data
)
2156 tree type
= (tree
) data
;
2158 if (TREE_VIA_VIRTUAL (binfo
))
2159 CLASSTYPE_VBASECLASSES (type
)
2160 = tree_cons (BINFO_TYPE (binfo
),
2162 CLASSTYPE_VBASECLASSES (type
));
2163 SET_BINFO_MARKED (binfo
);
2167 /* Called via dfs_walk from mark_primary_bases. Builds the
2168 inheritance graph order list of BINFOs. */
2171 dfs_build_inheritance_graph_order (binfo
, data
)
2175 tree
*last_binfo
= (tree
*) data
;
2178 TREE_CHAIN (*last_binfo
) = binfo
;
2179 *last_binfo
= binfo
;
2180 SET_BINFO_MARKED (binfo
);
2184 /* Set CLASSTYPE_VBASECLASSES for TYPE. */
2187 get_vbase_types (type
)
2192 CLASSTYPE_VBASECLASSES (type
) = NULL_TREE
;
2193 dfs_walk (TYPE_BINFO (type
), dfs_get_vbase_types
, unmarkedp
, type
);
2194 /* Rely upon the reverse dfs ordering from dfs_get_vbase_types, and now
2195 reverse it so that we get normal dfs ordering. */
2196 CLASSTYPE_VBASECLASSES (type
) = nreverse (CLASSTYPE_VBASECLASSES (type
));
2197 dfs_walk (TYPE_BINFO (type
), dfs_unmark
, markedp
, 0);
2198 /* Thread the BINFOs in inheritance-graph order. */
2200 dfs_walk_real (TYPE_BINFO (type
),
2201 dfs_build_inheritance_graph_order
,
2205 dfs_walk (TYPE_BINFO (type
), dfs_unmark
, markedp
, NULL
);
2208 /* Called from find_vbase_instance via dfs_walk. */
2211 dfs_find_vbase_instance (binfo
, data
)
2215 tree base
= TREE_VALUE ((tree
) data
);
2217 if (BINFO_PRIMARY_P (binfo
)
2218 && same_type_p (BINFO_TYPE (binfo
), base
))
2224 /* Find the real occurrence of the virtual BASE (a class type) in the
2225 hierarchy dominated by TYPE. */
2228 find_vbase_instance (base
, type
)
2234 instance
= binfo_for_vbase (base
, type
);
2235 if (!BINFO_PRIMARY_P (instance
))
2238 return dfs_walk (TYPE_BINFO (type
),
2239 dfs_find_vbase_instance
,
2241 build_tree_list (type
, base
));
2245 /* Debug info for C++ classes can get very large; try to avoid
2246 emitting it everywhere.
2248 Note that this optimization wins even when the target supports
2249 BINCL (if only slightly), and reduces the amount of work for the
2253 maybe_suppress_debug_info (t
)
2256 /* We can't do the usual TYPE_DECL_SUPPRESS_DEBUG thing with DWARF, which
2257 does not support name references between translation units. It supports
2258 symbolic references between translation units, but only within a single
2259 executable or shared library.
2261 For DWARF 2, we handle TYPE_DECL_SUPPRESS_DEBUG by pretending
2262 that the type was never defined, so we only get the members we
2264 if (write_symbols
== DWARF_DEBUG
|| write_symbols
== NO_DEBUG
)
2267 /* We might have set this earlier in cp_finish_decl. */
2268 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t
)) = 0;
2270 /* If we already know how we're handling this class, handle debug info
2272 if (CLASSTYPE_INTERFACE_KNOWN (t
))
2274 if (CLASSTYPE_INTERFACE_ONLY (t
))
2275 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t
)) = 1;
2276 /* else don't set it. */
2278 /* If the class has a vtable, write out the debug info along with
2280 else if (TYPE_CONTAINS_VPTR_P (t
))
2281 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t
)) = 1;
2283 /* Otherwise, just emit the debug info normally. */
2286 /* Note that we want debugging information for a base class of a class
2287 whose vtable is being emitted. Normally, this would happen because
2288 calling the constructor for a derived class implies calling the
2289 constructors for all bases, which involve initializing the
2290 appropriate vptr with the vtable for the base class; but in the
2291 presence of optimization, this initialization may be optimized
2292 away, so we tell finish_vtable_vardecl that we want the debugging
2293 information anyway. */
2296 dfs_debug_mark (binfo
, data
)
2298 void *data ATTRIBUTE_UNUSED
;
2300 tree t
= BINFO_TYPE (binfo
);
2302 CLASSTYPE_DEBUG_REQUESTED (t
) = 1;
2307 /* Returns BINFO if we haven't already noted that we want debugging
2308 info for this base class. */
2311 dfs_debug_unmarkedp (binfo
, data
)
2313 void *data ATTRIBUTE_UNUSED
;
2315 return (!CLASSTYPE_DEBUG_REQUESTED (BINFO_TYPE (binfo
))
2316 ? binfo
: NULL_TREE
);
2319 /* Write out the debugging information for TYPE, whose vtable is being
2320 emitted. Also walk through our bases and note that we want to
2321 write out information for them. This avoids the problem of not
2322 writing any debug info for intermediate basetypes whose
2323 constructors, and thus the references to their vtables, and thus
2324 the vtables themselves, were optimized away. */
2327 note_debug_info_needed (type
)
2330 if (TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type
)))
2332 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type
)) = 0;
2333 rest_of_type_compilation (type
, toplevel_bindings_p ());
2336 dfs_walk (TYPE_BINFO (type
), dfs_debug_mark
, dfs_debug_unmarkedp
, 0);
2339 /* Subroutines of push_class_decls (). */
2341 /* Returns 1 iff BINFO is a base we shouldn't really be able to see into,
2342 because it (or one of the intermediate bases) depends on template parms. */
2345 dependent_base_p (binfo
)
2348 for (; binfo
; binfo
= BINFO_INHERITANCE_CHAIN (binfo
))
2350 if (currently_open_class (TREE_TYPE (binfo
)))
2352 if (uses_template_parms (TREE_TYPE (binfo
)))
2359 setup_class_bindings (name
, type_binding_p
)
2363 tree type_binding
= NULL_TREE
;
2366 /* If we've already done the lookup for this declaration, we're
2368 if (IDENTIFIER_CLASS_VALUE (name
))
2371 /* First, deal with the type binding. */
2374 type_binding
= lookup_member (current_class_type
, name
,
2377 if (TREE_CODE (type_binding
) == TREE_LIST
2378 && TREE_TYPE (type_binding
) == error_mark_node
)
2379 /* NAME is ambiguous. */
2380 push_class_level_binding (name
, type_binding
);
2382 pushdecl_class_level (type_binding
);
2385 /* Now, do the value binding. */
2386 value_binding
= lookup_member (current_class_type
, name
,
2391 && (TREE_CODE (value_binding
) == TYPE_DECL
2392 || DECL_CLASS_TEMPLATE_P (value_binding
)
2393 || (TREE_CODE (value_binding
) == TREE_LIST
2394 && TREE_TYPE (value_binding
) == error_mark_node
2395 && (TREE_CODE (TREE_VALUE (value_binding
))
2397 /* We found a type-binding, even when looking for a non-type
2398 binding. This means that we already processed this binding
2400 else if (value_binding
)
2402 if (TREE_CODE (value_binding
) == TREE_LIST
2403 && TREE_TYPE (value_binding
) == error_mark_node
)
2404 /* NAME is ambiguous. */
2405 push_class_level_binding (name
, value_binding
);
2408 if (BASELINK_P (value_binding
))
2409 /* NAME is some overloaded functions. */
2410 value_binding
= TREE_VALUE (value_binding
);
2411 pushdecl_class_level (value_binding
);
2416 /* Push class-level declarations for any names appearing in BINFO that
2420 dfs_push_type_decls (binfo
, data
)
2422 void *data ATTRIBUTE_UNUSED
;
2427 type
= BINFO_TYPE (binfo
);
2428 for (fields
= TYPE_FIELDS (type
); fields
; fields
= TREE_CHAIN (fields
))
2429 if (DECL_NAME (fields
) && TREE_CODE (fields
) == TYPE_DECL
2430 && !(!same_type_p (type
, current_class_type
)
2431 && template_self_reference_p (type
, fields
)))
2432 setup_class_bindings (DECL_NAME (fields
), /*type_binding_p=*/1);
2434 /* We can't just use BINFO_MARKED because envelope_add_decl uses
2435 DERIVED_FROM_P, which calls get_base_distance. */
2436 SET_BINFO_PUSHDECLS_MARKED (binfo
);
2441 /* Push class-level declarations for any names appearing in BINFO that
2442 are not TYPE_DECLS. */
2445 dfs_push_decls (binfo
, data
)
2453 type
= BINFO_TYPE (binfo
);
2454 dep_base_p
= (processing_template_decl
&& type
!= current_class_type
2455 && dependent_base_p (binfo
));
2459 for (fields
= TYPE_FIELDS (type
); fields
; fields
= TREE_CHAIN (fields
))
2460 if (DECL_NAME (fields
)
2461 && TREE_CODE (fields
) != TYPE_DECL
2462 && TREE_CODE (fields
) != USING_DECL
)
2463 setup_class_bindings (DECL_NAME (fields
), /*type_binding_p=*/0);
2464 else if (TREE_CODE (fields
) == FIELD_DECL
2465 && ANON_AGGR_TYPE_P (TREE_TYPE (fields
)))
2466 dfs_push_decls (TYPE_BINFO (TREE_TYPE (fields
)), data
);
2468 method_vec
= (CLASS_TYPE_P (type
)
2469 ? CLASSTYPE_METHOD_VEC (type
) : NULL_TREE
);
2475 /* Farm out constructors and destructors. */
2476 end
= TREE_VEC_END (method_vec
);
2478 for (methods
= &TREE_VEC_ELT (method_vec
, 2);
2479 *methods
&& methods
!= end
;
2481 setup_class_bindings (DECL_NAME (OVL_CURRENT (*methods
)),
2482 /*type_binding_p=*/0);
2486 CLEAR_BINFO_PUSHDECLS_MARKED (binfo
);
2491 /* When entering the scope of a class, we cache all of the
2492 fields that that class provides within its inheritance
2493 lattice. Where ambiguities result, we mark them
2494 with `error_mark_node' so that if they are encountered
2495 without explicit qualification, we can emit an error
2499 push_class_decls (type
)
2502 search_stack
= push_search_level (search_stack
, &search_obstack
);
2504 /* Enter type declarations and mark. */
2505 dfs_walk (TYPE_BINFO (type
), dfs_push_type_decls
, unmarked_pushdecls_p
, 0);
2507 /* Enter non-type declarations and unmark. */
2508 dfs_walk (TYPE_BINFO (type
), dfs_push_decls
, marked_pushdecls_p
, 0);
2511 /* Here's a subroutine we need because C lacks lambdas. */
2514 dfs_unuse_fields (binfo
, data
)
2516 void *data ATTRIBUTE_UNUSED
;
2518 tree type
= TREE_TYPE (binfo
);
2521 for (fields
= TYPE_FIELDS (type
); fields
; fields
= TREE_CHAIN (fields
))
2523 if (TREE_CODE (fields
) != FIELD_DECL
)
2526 TREE_USED (fields
) = 0;
2527 if (DECL_NAME (fields
) == NULL_TREE
2528 && ANON_AGGR_TYPE_P (TREE_TYPE (fields
)))
2529 unuse_fields (TREE_TYPE (fields
));
2539 dfs_walk (TYPE_BINFO (type
), dfs_unuse_fields
, unmarkedp
, 0);
2545 /* We haven't pushed a search level when dealing with cached classes,
2546 so we'd better not try to pop it. */
2548 search_stack
= pop_search_level (search_stack
);
2552 print_search_statistics ()
2554 #ifdef GATHER_STATISTICS
2555 fprintf (stderr
, "%d fields searched in %d[%d] calls to lookup_field[_1]\n",
2556 n_fields_searched
, n_calls_lookup_field
, n_calls_lookup_field_1
);
2557 fprintf (stderr
, "%d fnfields searched in %d calls to lookup_fnfields\n",
2558 n_outer_fields_searched
, n_calls_lookup_fnfields
);
2559 fprintf (stderr
, "%d calls to get_base_type\n", n_calls_get_base_type
);
2560 #else /* GATHER_STATISTICS */
2561 fprintf (stderr
, "no search statistics\n");
2562 #endif /* GATHER_STATISTICS */
2566 init_search_processing ()
2568 gcc_obstack_init (&search_obstack
);
2572 reinit_search_statistics ()
2574 #ifdef GATHER_STATISTICS
2575 n_fields_searched
= 0;
2576 n_calls_lookup_field
= 0, n_calls_lookup_field_1
= 0;
2577 n_calls_lookup_fnfields
= 0, n_calls_lookup_fnfields_1
= 0;
2578 n_calls_get_base_type
= 0;
2579 n_outer_fields_searched
= 0;
2580 n_contexts_saved
= 0;
2581 #endif /* GATHER_STATISTICS */
2585 add_conversions (binfo
, data
)
2590 tree method_vec
= CLASSTYPE_METHOD_VEC (BINFO_TYPE (binfo
));
2591 tree
*conversions
= (tree
*) data
;
2593 /* Some builtin types have no method vector, not even an empty one. */
2597 for (i
= 2; i
< TREE_VEC_LENGTH (method_vec
); ++i
)
2599 tree tmp
= TREE_VEC_ELT (method_vec
, i
);
2602 if (!tmp
|| ! DECL_CONV_FN_P (OVL_CURRENT (tmp
)))
2605 name
= DECL_NAME (OVL_CURRENT (tmp
));
2607 /* Make sure we don't already have this conversion. */
2608 if (! IDENTIFIER_MARKED (name
))
2610 *conversions
= tree_cons (binfo
, tmp
, *conversions
);
2611 IDENTIFIER_MARKED (name
) = 1;
2617 /* Return a TREE_LIST containing all the non-hidden user-defined
2618 conversion functions for TYPE (and its base-classes). The
2619 TREE_VALUE of each node is a FUNCTION_DECL or an OVERLOAD
2620 containing the conversion functions. The TREE_PURPOSE is the BINFO
2621 from which the conversion functions in this node were selected. */
2624 lookup_conversions (type
)
2628 tree conversions
= NULL_TREE
;
2630 if (COMPLETE_TYPE_P (type
))
2631 bfs_walk (TYPE_BINFO (type
), add_conversions
, 0, &conversions
);
2633 for (t
= conversions
; t
; t
= TREE_CHAIN (t
))
2634 IDENTIFIER_MARKED (DECL_NAME (OVL_CURRENT (TREE_VALUE (t
)))) = 0;
2645 /* Check whether the empty class indicated by EMPTY_BINFO is also present
2646 at offset 0 in COMPARE_TYPE, and set found_overlap if so. */
2649 dfs_check_overlap (empty_binfo
, data
)
2653 struct overlap_info
*oi
= (struct overlap_info
*) data
;
2655 for (binfo
= TYPE_BINFO (oi
->compare_type
);
2657 binfo
= BINFO_BASETYPE (binfo
, 0))
2659 if (BINFO_TYPE (binfo
) == BINFO_TYPE (empty_binfo
))
2661 oi
->found_overlap
= 1;
2664 else if (BINFO_BASETYPES (binfo
) == NULL_TREE
)
2671 /* Trivial function to stop base traversal when we find something. */
2674 dfs_no_overlap_yet (binfo
, data
)
2678 struct overlap_info
*oi
= (struct overlap_info
*) data
;
2679 return !oi
->found_overlap
? binfo
: NULL_TREE
;
2682 /* Returns nonzero if EMPTY_TYPE or any of its bases can also be found at
2683 offset 0 in NEXT_TYPE. Used in laying out empty base class subobjects. */
2686 types_overlap_p (empty_type
, next_type
)
2687 tree empty_type
, next_type
;
2689 struct overlap_info oi
;
2691 if (! IS_AGGR_TYPE (next_type
))
2693 oi
.compare_type
= next_type
;
2694 oi
.found_overlap
= 0;
2695 dfs_walk (TYPE_BINFO (empty_type
), dfs_check_overlap
,
2696 dfs_no_overlap_yet
, &oi
);
2697 return oi
.found_overlap
;
2700 /* Given a vtable VAR, determine which of the inherited classes the vtable
2701 inherits (in a loose sense) functions from.
2703 FIXME: This does not work with the new ABI. */
2706 binfo_for_vtable (var
)
2709 tree main_binfo
= TYPE_BINFO (DECL_CONTEXT (var
));
2710 tree binfos
= TYPE_BINFO_BASETYPES (BINFO_TYPE (main_binfo
));
2711 int n_baseclasses
= CLASSTYPE_N_BASECLASSES (BINFO_TYPE (main_binfo
));
2714 for (i
= 0; i
< n_baseclasses
; i
++)
2716 tree base_binfo
= TREE_VEC_ELT (binfos
, i
);
2717 if (base_binfo
!= NULL_TREE
&& BINFO_VTABLE (base_binfo
) == var
)
2721 /* If no secondary base classes matched, return the primary base, if
2723 if (CLASSTYPE_HAS_PRIMARY_BASE_P (BINFO_TYPE (main_binfo
)))
2724 return get_primary_binfo (main_binfo
);
2729 /* Returns the binfo of the first direct or indirect virtual base derived
2730 from BINFO, or NULL if binfo is not via virtual. */
2733 binfo_from_vbase (binfo
)
2736 for (; binfo
; binfo
= BINFO_INHERITANCE_CHAIN (binfo
))
2738 if (TREE_VIA_VIRTUAL (binfo
))
2744 /* Returns the binfo of the first direct or indirect virtual base derived
2745 from BINFO up to the TREE_TYPE, LIMIT, or NULL if binfo is not
2749 binfo_via_virtual (binfo
, limit
)
2753 for (; binfo
&& (!limit
|| !same_type_p (BINFO_TYPE (binfo
), limit
));
2754 binfo
= BINFO_INHERITANCE_CHAIN (binfo
))
2756 if (TREE_VIA_VIRTUAL (binfo
))
2762 /* Returns the BINFO (if any) for the virtual baseclass T of the class
2763 C from the CLASSTYPE_VBASECLASSES list. */
2766 binfo_for_vbase (basetype
, classtype
)
2772 binfo
= purpose_member (basetype
, CLASSTYPE_VBASECLASSES (classtype
));
2773 return binfo
? TREE_VALUE (binfo
) : NULL_TREE
;