1 /* Breadth-first and depth-first routines for
2 searching multiple-inheritance lattice for GNU C++.
3 Copyright (C) 1987-2020 Free Software Foundation, Inc.
4 Contributed by Michael Tiemann (tiemann@cygnus.com)
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
13 GCC is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* High-level class interface. */
26 #include "coretypes.h"
30 #include "spellcheck-tree.h"
31 #include "stringpool.h"
34 static int is_subobject_of_p (tree
, tree
);
35 static tree
dfs_lookup_base (tree
, void *);
36 static tree
dfs_dcast_hint_pre (tree
, void *);
37 static tree
dfs_dcast_hint_post (tree
, void *);
38 static tree
dfs_debug_mark (tree
, void *);
39 static int check_hidden_convs (tree
, int, int, tree
, tree
, tree
);
40 static tree
split_conversions (tree
, tree
, tree
, tree
);
41 static int lookup_conversions_r (tree
, int, int, tree
, tree
, tree
*);
42 static int look_for_overrides_r (tree
, tree
);
43 static tree
lookup_field_r (tree
, void *);
44 static tree
dfs_accessible_post (tree
, void *);
45 static tree
dfs_walk_once_accessible (tree
, bool,
46 tree (*pre_fn
) (tree
, void *),
47 tree (*post_fn
) (tree
, void *),
49 static tree
dfs_access_in_type (tree
, void *);
50 static access_kind
access_in_type (tree
, tree
);
51 static tree
dfs_get_pure_virtuals (tree
, void *);
54 /* Data for lookup_base and its workers. */
56 struct lookup_base_data_s
58 tree t
; /* type being searched. */
59 tree base
; /* The base type we're looking for. */
60 tree binfo
; /* Found binfo. */
61 bool via_virtual
; /* Found via a virtual path. */
62 bool ambiguous
; /* Found multiply ambiguous */
63 bool repeated_base
; /* Whether there are repeated bases in the
65 bool want_any
; /* Whether we want any matching binfo. */
68 /* Worker function for lookup_base. See if we've found the desired
69 base and update DATA_ (a pointer to LOOKUP_BASE_DATA_S). */
72 dfs_lookup_base (tree binfo
, void *data_
)
74 struct lookup_base_data_s
*data
= (struct lookup_base_data_s
*) data_
;
76 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), data
->base
))
82 = binfo_via_virtual (data
->binfo
, data
->t
) != NULL_TREE
;
84 if (!data
->repeated_base
)
85 /* If there are no repeated bases, we can stop now. */
88 if (data
->want_any
&& !data
->via_virtual
)
89 /* If this is a non-virtual base, then we can't do
93 return dfs_skip_bases
;
97 gcc_assert (binfo
!= data
->binfo
);
99 /* We've found more than one matching binfo. */
102 /* This is immediately ambiguous. */
103 data
->binfo
= NULL_TREE
;
104 data
->ambiguous
= true;
105 return error_mark_node
;
108 /* Prefer one via a non-virtual path. */
109 if (!binfo_via_virtual (binfo
, data
->t
))
112 data
->via_virtual
= false;
116 /* There must be repeated bases, otherwise we'd have stopped
117 on the first base we found. */
118 return dfs_skip_bases
;
125 /* Returns true if type BASE is accessible in T. (BASE is known to be
126 a (possibly non-proper) base class of T.) If CONSIDER_LOCAL_P is
127 true, consider any special access of the current scope, or access
128 bestowed by friendship. */
131 accessible_base_p (tree t
, tree base
, bool consider_local_p
)
135 /* [class.access.base]
137 A base class is said to be accessible if an invented public
138 member of the base class is accessible.
140 If BASE is a non-proper base, this condition is trivially
142 if (same_type_p (t
, base
))
144 /* Rather than inventing a public member, we use the implicit
145 public typedef created in the scope of every class. */
146 decl
= TYPE_FIELDS (base
);
147 while (!DECL_SELF_REFERENCE_P (decl
))
148 decl
= DECL_CHAIN (decl
);
149 while (ANON_AGGR_TYPE_P (t
))
150 t
= TYPE_CONTEXT (t
);
151 return accessible_p (t
, decl
, consider_local_p
);
154 /* Lookup BASE in the hierarchy dominated by T. Do access checking as
155 ACCESS specifies. Return the binfo we discover. If KIND_PTR is
156 non-NULL, fill with information about what kind of base we
159 If the base is inaccessible, or ambiguous, then error_mark_node is
160 returned. If the tf_error bit of COMPLAIN is not set, no error
164 lookup_base (tree t
, tree base
, base_access access
,
165 base_kind
*kind_ptr
, tsubst_flags_t complain
)
171 /* "Nothing" is definitely not derived from Base. */
175 *kind_ptr
= bk_not_base
;
179 if (t
== error_mark_node
|| base
== error_mark_node
)
182 *kind_ptr
= bk_not_base
;
183 return error_mark_node
;
185 gcc_assert (TYPE_P (base
));
194 t
= complete_type (TYPE_MAIN_VARIANT (t
));
195 if (dependent_type_p (t
))
196 if (tree open
= currently_open_class (t
))
198 t_binfo
= TYPE_BINFO (t
);
201 base
= TYPE_MAIN_VARIANT (base
);
203 /* If BASE is incomplete, it can't be a base of T--and instantiating it
204 might cause an error. */
205 if (t_binfo
&& CLASS_TYPE_P (base
) && COMPLETE_OR_OPEN_TYPE_P (base
))
207 struct lookup_base_data_s data
;
211 data
.binfo
= NULL_TREE
;
212 data
.ambiguous
= data
.via_virtual
= false;
213 data
.repeated_base
= CLASSTYPE_REPEATED_BASE_P (t
);
214 data
.want_any
= access
== ba_any
;
216 dfs_walk_once (t_binfo
, dfs_lookup_base
, NULL
, &data
);
220 bk
= data
.ambiguous
? bk_ambig
: bk_not_base
;
221 else if (binfo
== t_binfo
)
223 else if (data
.via_virtual
)
234 /* Check that the base is unambiguous and accessible. */
235 if (access
!= ba_any
)
242 if (complain
& tf_error
)
243 error ("%qT is an ambiguous base of %qT", base
, t
);
244 binfo
= error_mark_node
;
248 if ((access
& ba_check_bit
)
249 /* If BASE is incomplete, then BASE and TYPE are probably
250 the same, in which case BASE is accessible. If they
251 are not the same, then TYPE is invalid. In that case,
252 there's no need to issue another error here, and
253 there's no implicit typedef to use in the code that
254 follows, so we skip the check. */
255 && COMPLETE_TYPE_P (base
)
256 && !accessible_base_p (t
, base
, !(access
& ba_ignore_scope
)))
258 if (complain
& tf_error
)
259 error ("%qT is an inaccessible base of %qT", base
, t
);
260 binfo
= error_mark_node
;
261 bk
= bk_inaccessible
;
272 /* Data for dcast_base_hint walker. */
276 tree subtype
; /* The base type we're looking for. */
277 int virt_depth
; /* Number of virtual bases encountered from most
279 tree offset
; /* Best hint offset discovered so far. */
280 bool repeated_base
; /* Whether there are repeated bases in the
284 /* Worker for dcast_base_hint. Search for the base type being cast
288 dfs_dcast_hint_pre (tree binfo
, void *data_
)
290 struct dcast_data_s
*data
= (struct dcast_data_s
*) data_
;
292 if (BINFO_VIRTUAL_P (binfo
))
295 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), data
->subtype
))
297 if (data
->virt_depth
)
299 data
->offset
= ssize_int (-1);
303 data
->offset
= ssize_int (-3);
305 data
->offset
= BINFO_OFFSET (binfo
);
307 return data
->repeated_base
? dfs_skip_bases
: data
->offset
;
313 /* Worker for dcast_base_hint. Track the virtual depth. */
316 dfs_dcast_hint_post (tree binfo
, void *data_
)
318 struct dcast_data_s
*data
= (struct dcast_data_s
*) data_
;
320 if (BINFO_VIRTUAL_P (binfo
))
326 /* The dynamic cast runtime needs a hint about how the static SUBTYPE type
327 started from is related to the required TARGET type, in order to optimize
328 the inheritance graph search. This information is independent of the
329 current context, and ignores private paths, hence get_base_distance is
330 inappropriate. Return a TREE specifying the base offset, BOFF.
331 BOFF >= 0, there is only one public non-virtual SUBTYPE base at offset BOFF,
332 and there are no public virtual SUBTYPE bases.
333 BOFF == -1, SUBTYPE occurs as multiple public virtual or non-virtual bases.
334 BOFF == -2, SUBTYPE is not a public base.
335 BOFF == -3, SUBTYPE occurs as multiple public non-virtual bases. */
338 dcast_base_hint (tree subtype
, tree target
)
340 struct dcast_data_s data
;
342 data
.subtype
= subtype
;
344 data
.offset
= NULL_TREE
;
345 data
.repeated_base
= CLASSTYPE_REPEATED_BASE_P (target
);
347 dfs_walk_once_accessible (TYPE_BINFO (target
), /*friends=*/false,
348 dfs_dcast_hint_pre
, dfs_dcast_hint_post
, &data
);
349 return data
.offset
? data
.offset
: ssize_int (-2);
352 /* Search for a member with name NAME in a multiple inheritance
353 lattice specified by TYPE. If it does not exist, return NULL_TREE.
354 If the member is ambiguously referenced, return `error_mark_node'.
355 Otherwise, return a DECL with the indicated name. If WANT_TYPE is
356 true, type declarations are preferred. */
358 /* Return the FUNCTION_DECL, RECORD_TYPE, UNION_TYPE, or
359 NAMESPACE_DECL corresponding to the innermost non-block scope. */
364 /* There are a number of cases we need to be aware of here:
365 current_class_type current_function_decl
372 Those last two make life interesting. If we're in a function which is
373 itself inside a class, we need decls to go into the fn's decls (our
374 second case below). But if we're in a class and the class itself is
375 inside a function, we need decls to go into the decls for the class. To
376 achieve this last goal, we must see if, when both current_class_ptr and
377 current_function_decl are set, the class was declared inside that
378 function. If so, we know to put the decls into the class's scope. */
379 if (current_function_decl
&& current_class_type
380 && ((DECL_FUNCTION_MEMBER_P (current_function_decl
)
381 && same_type_p (DECL_CONTEXT (current_function_decl
),
383 || (DECL_FRIEND_CONTEXT (current_function_decl
)
384 && same_type_p (DECL_FRIEND_CONTEXT (current_function_decl
),
385 current_class_type
))))
386 return current_function_decl
;
388 if (current_class_type
)
389 return current_class_type
;
391 if (current_function_decl
)
392 return current_function_decl
;
394 return current_namespace
;
397 /* Returns nonzero if we are currently in a function scope. Note
398 that this function returns zero if we are within a local class, but
399 not within a member function body of the local class. */
402 at_function_scope_p (void)
404 tree cs
= current_scope ();
405 /* Also check cfun to make sure that we're really compiling
406 this function (as opposed to having set current_function_decl
407 for access checking or some such). */
408 return (cs
&& TREE_CODE (cs
) == FUNCTION_DECL
409 && cfun
&& cfun
->decl
== current_function_decl
);
412 /* Returns true if the innermost active scope is a class scope. */
415 at_class_scope_p (void)
417 tree cs
= current_scope ();
418 return cs
&& TYPE_P (cs
);
421 /* Returns true if the innermost active scope is a namespace scope. */
424 at_namespace_scope_p (void)
426 tree cs
= current_scope ();
427 return cs
&& TREE_CODE (cs
) == NAMESPACE_DECL
;
430 /* Return the scope of DECL, as appropriate when doing name-lookup. */
433 context_for_name_lookup (tree decl
)
437 For the purposes of name lookup, after the anonymous union
438 definition, the members of the anonymous union are considered to
439 have been defined in the scope in which the anonymous union is
441 tree context
= DECL_CONTEXT (decl
);
443 while (context
&& TYPE_P (context
)
444 && (ANON_AGGR_TYPE_P (context
) || UNSCOPED_ENUM_P (context
)))
445 context
= TYPE_CONTEXT (context
);
447 context
= global_namespace
;
452 /* Returns true iff DECL is declared in TYPE. */
455 member_declared_in_type (tree decl
, tree type
)
457 /* A normal declaration obviously counts. */
458 if (context_for_name_lookup (decl
) == type
)
460 /* So does a using or access declaration. */
461 if (DECL_LANG_SPECIFIC (decl
) && !DECL_DISCRIMINATOR_P (decl
)
462 && purpose_member (type
, DECL_ACCESS (decl
)))
467 /* The accessibility routines use BINFO_ACCESS for scratch space
468 during the computation of the accessibility of some declaration. */
470 /* Avoid walking up past a declaration of the member. */
473 dfs_access_in_type_pre (tree binfo
, void *data
)
475 tree decl
= (tree
) data
;
476 tree type
= BINFO_TYPE (binfo
);
477 if (member_declared_in_type (decl
, type
))
478 return dfs_skip_bases
;
482 #define BINFO_ACCESS(NODE) \
483 ((access_kind) ((TREE_PUBLIC (NODE) << 1) | TREE_PRIVATE (NODE)))
485 /* Set the access associated with NODE to ACCESS. */
487 #define SET_BINFO_ACCESS(NODE, ACCESS) \
488 ((TREE_PUBLIC (NODE) = ((ACCESS) & 2) != 0), \
489 (TREE_PRIVATE (NODE) = ((ACCESS) & 1) != 0))
491 /* Called from access_in_type via dfs_walk. Calculate the access to
492 DATA (which is really a DECL) in BINFO. */
495 dfs_access_in_type (tree binfo
, void *data
)
497 tree decl
= (tree
) data
;
498 tree type
= BINFO_TYPE (binfo
);
499 access_kind access
= ak_none
;
501 if (context_for_name_lookup (decl
) == type
)
503 /* If we have descended to the scope of DECL, just note the
504 appropriate access. */
505 if (TREE_PRIVATE (decl
))
507 else if (TREE_PROTECTED (decl
))
508 access
= ak_protected
;
514 /* First, check for an access-declaration that gives us more
515 access to the DECL. */
516 if (DECL_LANG_SPECIFIC (decl
) && !DECL_DISCRIMINATOR_P (decl
))
518 tree decl_access
= purpose_member (type
, DECL_ACCESS (decl
));
522 decl_access
= TREE_VALUE (decl_access
);
524 if (decl_access
== access_public_node
)
526 else if (decl_access
== access_protected_node
)
527 access
= ak_protected
;
528 else if (decl_access
== access_private_node
)
539 vec
<tree
, va_gc
> *accesses
;
541 /* Otherwise, scan our baseclasses, and pick the most favorable
543 accesses
= BINFO_BASE_ACCESSES (binfo
);
544 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
546 tree base_access
= (*accesses
)[i
];
547 access_kind base_access_now
= BINFO_ACCESS (base_binfo
);
549 if (base_access_now
== ak_none
|| base_access_now
== ak_private
)
550 /* If it was not accessible in the base, or only
551 accessible as a private member, we can't access it
553 base_access_now
= ak_none
;
554 else if (base_access
== access_protected_node
)
555 /* Public and protected members in the base become
557 base_access_now
= ak_protected
;
558 else if (base_access
== access_private_node
)
559 /* Public and protected members in the base become
561 base_access_now
= ak_private
;
563 /* See if the new access, via this base, gives more
564 access than our previous best access. */
565 if (base_access_now
!= ak_none
566 && (access
== ak_none
|| base_access_now
< access
))
568 access
= base_access_now
;
570 /* If the new access is public, we can't do better. */
571 if (access
== ak_public
)
578 /* Note the access to DECL in TYPE. */
579 SET_BINFO_ACCESS (binfo
, access
);
584 /* Return the access to DECL in TYPE. */
587 access_in_type (tree type
, tree decl
)
589 tree binfo
= TYPE_BINFO (type
);
591 /* We must take into account
595 If a name can be reached by several paths through a multiple
596 inheritance graph, the access is that of the path that gives
599 The algorithm we use is to make a post-order depth-first traversal
600 of the base-class hierarchy. As we come up the tree, we annotate
601 each node with the most lenient access. */
602 dfs_walk_once (binfo
, dfs_access_in_type_pre
, dfs_access_in_type
, decl
);
604 return BINFO_ACCESS (binfo
);
607 /* Returns nonzero if it is OK to access DECL named in TYPE through an object
608 of OTYPE in the context of DERIVED. */
611 protected_accessible_p (tree decl
, tree derived
, tree type
, tree otype
)
613 /* We're checking this clause from [class.access.base]
615 m as a member of N is protected, and the reference occurs in a
616 member or friend of class N, or in a member or friend of a
617 class P derived from N, where m as a member of P is public, private
620 Here DERIVED is a possible P, DECL is m and TYPE is N. */
622 /* If DERIVED isn't derived from N, then it can't be a P. */
623 if (!DERIVED_FROM_P (type
, derived
))
626 /* DECL_NONSTATIC_MEMBER_P won't work for USING_DECLs. */
627 decl
= strip_using_decl (decl
);
628 /* We don't expect or support dependent decls. */
629 gcc_assert (TREE_CODE (decl
) != USING_DECL
);
633 When a friend or a member function of a derived class references
634 a protected nonstatic member of a base class, an access check
635 applies in addition to those described earlier in clause
636 _class.access_) Except when forming a pointer to member
637 (_expr.unary.op_), the access must be through a pointer to,
638 reference to, or object of the derived class itself (or any class
639 derived from that class) (_expr.ref_). If the access is to form
640 a pointer to member, the nested-name-specifier shall name the
641 derived class (or any class derived from that class). */
642 if (DECL_NONSTATIC_MEMBER_P (decl
)
643 && !DERIVED_FROM_P (derived
, otype
))
649 /* Returns nonzero if SCOPE is a type or a friend of a type which would be able
650 to access DECL through TYPE. OTYPE is the type of the object. */
653 friend_accessible_p (tree scope
, tree decl
, tree type
, tree otype
)
655 /* We're checking this clause from [class.access.base]
657 m as a member of N is protected, and the reference occurs in a
658 member or friend of class N, or in a member or friend of a
659 class P derived from N, where m as a member of P is public, private
662 Here DECL is m and TYPE is N. SCOPE is the current context,
663 and we check all its possible Ps. */
664 tree befriending_classes
;
670 if (is_global_friend (scope
))
673 /* Is SCOPE itself a suitable P? */
674 if (TYPE_P (scope
) && protected_accessible_p (decl
, scope
, type
, otype
))
677 if (DECL_DECLARES_FUNCTION_P (scope
))
678 befriending_classes
= DECL_BEFRIENDING_CLASSES (scope
);
679 else if (TYPE_P (scope
))
680 befriending_classes
= CLASSTYPE_BEFRIENDING_CLASSES (scope
);
684 for (t
= befriending_classes
; t
; t
= TREE_CHAIN (t
))
685 if (protected_accessible_p (decl
, TREE_VALUE (t
), type
, otype
))
688 /* Nested classes have the same access as their enclosing types, as
689 per DR 45 (this is a change from C++98). */
691 if (friend_accessible_p (TYPE_CONTEXT (scope
), decl
, type
, otype
))
694 if (DECL_DECLARES_FUNCTION_P (scope
))
696 /* Perhaps this SCOPE is a member of a class which is a
698 if (DECL_CLASS_SCOPE_P (scope
)
699 && friend_accessible_p (DECL_CONTEXT (scope
), decl
, type
, otype
))
703 /* Maybe scope's template is a friend. */
704 if (tree tinfo
= get_template_info (scope
))
706 tree tmpl
= TI_TEMPLATE (tinfo
);
707 if (DECL_CLASS_TEMPLATE_P (tmpl
))
708 tmpl
= TREE_TYPE (tmpl
);
710 tmpl
= DECL_TEMPLATE_RESULT (tmpl
);
713 /* Increment processing_template_decl to make sure that
714 dependent_type_p works correctly. */
715 ++processing_template_decl
;
716 int ret
= friend_accessible_p (tmpl
, decl
, type
, otype
);
717 --processing_template_decl
;
723 /* If is_friend is true, we should have found a befriending class. */
724 gcc_checking_assert (!is_friend (type
, scope
));
729 struct dfs_accessible_data
735 /* Avoid walking up past a declaration of the member. */
738 dfs_accessible_pre (tree binfo
, void *data
)
740 dfs_accessible_data
*d
= (dfs_accessible_data
*)data
;
741 tree type
= BINFO_TYPE (binfo
);
742 if (member_declared_in_type (d
->decl
, type
))
743 return dfs_skip_bases
;
747 /* Called via dfs_walk_once_accessible from accessible_p */
750 dfs_accessible_post (tree binfo
, void *data
)
752 /* access_in_type already set BINFO_ACCESS for us. */
753 access_kind access
= BINFO_ACCESS (binfo
);
754 tree N
= BINFO_TYPE (binfo
);
755 dfs_accessible_data
*d
= (dfs_accessible_data
*)data
;
757 tree scope
= current_nonlambda_scope ();
759 /* A member m is accessible at the point R when named in class N if */
766 /* m as a member of N is public, or */
771 /* m as a member of N is private, and R occurs in a member or friend of
773 if (scope
&& TREE_CODE (scope
) != NAMESPACE_DECL
774 && is_friend (N
, scope
))
781 /* m as a member of N is protected, and R occurs in a member or friend
782 of class N, or in a member or friend of a class P derived from N,
783 where m as a member of P is public, private, or protected */
784 if (friend_accessible_p (scope
, decl
, N
, d
->object_type
))
794 /* Like accessible_p below, but within a template returns true iff DECL is
795 accessible in TYPE to all possible instantiations of the template. */
798 accessible_in_template_p (tree type
, tree decl
)
800 int save_ptd
= processing_template_decl
;
801 processing_template_decl
= 0;
802 int val
= accessible_p (type
, decl
, false);
803 processing_template_decl
= save_ptd
;
807 /* DECL is a declaration from a base class of TYPE, which was the
808 class used to name DECL. Return nonzero if, in the current
809 context, DECL is accessible. If TYPE is actually a BINFO node,
810 then we can tell in what context the access is occurring by looking
811 at the most derived class along the path indicated by BINFO. If
812 CONSIDER_LOCAL is true, do consider special access the current
813 scope or friendship thereof we might have. */
816 accessible_p (tree type
, tree decl
, bool consider_local_p
)
821 /* If this declaration is in a block or namespace scope, there's no
823 if (!TYPE_P (context_for_name_lookup (decl
)))
826 /* There is no need to perform access checks inside a thunk. */
827 if (current_function_decl
&& DECL_THUNK_P (current_function_decl
))
830 /* In a template declaration, we cannot be sure whether the
831 particular specialization that is instantiated will be a friend
832 or not. Therefore, all access checks are deferred until
833 instantiation. However, PROCESSING_TEMPLATE_DECL is set in the
834 parameter list for a template (because we may see dependent types
835 in default arguments for template parameters), and access
836 checking should be performed in the outermost parameter list. */
837 if (processing_template_decl
838 /* FIXME CWG has been talking about doing access checking in the context
839 of the constraint-expression, rather than the constrained declaration,
840 in which case we would want to remove this test. */
841 && !processing_constraint_expression_p ()
842 && (!processing_template_parmlist
|| processing_template_decl
> 1))
845 tree otype
= NULL_TREE
;
848 /* When accessing a non-static member, the most derived type in the
849 binfo chain is the type of the object; remember that type for
850 protected_accessible_p. */
851 for (tree b
= type
; b
; b
= BINFO_INHERITANCE_CHAIN (b
))
852 otype
= BINFO_TYPE (b
);
853 type
= BINFO_TYPE (type
);
858 /* [class.access.base]
860 A member m is accessible when named in class N if
862 --m as a member of N is public, or
864 --m as a member of N is private, and the reference occurs in a
865 member or friend of class N, or
867 --m as a member of N is protected, and the reference occurs in a
868 member or friend of class N, or in a member or friend of a
869 class P derived from N, where m as a member of P is public, private or
872 --there exists a base class B of N that is accessible at the point
873 of reference, and m is accessible when named in class B.
875 We walk the base class hierarchy, checking these conditions. */
877 /* We walk using TYPE_BINFO (type) because access_in_type will set
878 BINFO_ACCESS on it and its bases. */
879 binfo
= TYPE_BINFO (type
);
881 /* Compute the accessibility of DECL in the class hierarchy
882 dominated by type. */
883 access
= access_in_type (type
, decl
);
884 if (access
== ak_public
)
887 /* If we aren't considering the point of reference, only the first bullet
889 if (!consider_local_p
)
892 dfs_accessible_data d
= { decl
, otype
};
894 /* Walk the hierarchy again, looking for a base class that allows
896 return dfs_walk_once_accessible (binfo
, /*friends=*/true,
898 dfs_accessible_post
, &d
)
902 struct lookup_field_info
{
903 /* The type in which we're looking. */
905 /* The name of the field for which we're looking. */
907 /* If non-NULL, the current result of the lookup. */
909 /* The path to RVAL. */
911 /* If non-NULL, the lookup was ambiguous, and this is a list of the
914 /* If nonzero, we are looking for types, not data members. */
916 /* If something went wrong, a message indicating what. */
920 /* Nonzero for a class member means that it is shared between all objects
923 [class.member.lookup]:If the resulting set of declarations are not all
924 from sub-objects of the same type, or the set has a nonstatic member
925 and includes members from distinct sub-objects, there is an ambiguity
926 and the program is ill-formed.
928 This function checks that T contains no nonstatic members. */
931 shared_member_p (tree t
)
933 if (VAR_P (t
) || TREE_CODE (t
) == TYPE_DECL \
934 || TREE_CODE (t
) == CONST_DECL
)
936 if (is_overloaded_fn (t
))
938 for (ovl_iterator
iter (get_fns (t
)); iter
; ++iter
)
940 tree decl
= strip_using_decl (*iter
);
941 /* We don't expect or support dependent decls. */
942 gcc_assert (TREE_CODE (decl
) != USING_DECL
);
943 if (DECL_NONSTATIC_MEMBER_FUNCTION_P (decl
))
951 /* Routine to see if the sub-object denoted by the binfo PARENT can be
952 found as a base class and sub-object of the object denoted by
956 is_subobject_of_p (tree parent
, tree binfo
)
960 for (probe
= parent
; probe
; probe
= BINFO_INHERITANCE_CHAIN (probe
))
964 if (BINFO_VIRTUAL_P (probe
))
965 return (binfo_for_vbase (BINFO_TYPE (probe
), BINFO_TYPE (binfo
))
971 /* DATA is really a struct lookup_field_info. Look for a field with
972 the name indicated there in BINFO. If this function returns a
973 non-NULL value it is the result of the lookup. Called from
974 lookup_field via breadth_first_search. */
977 lookup_field_r (tree binfo
, void *data
)
979 struct lookup_field_info
*lfi
= (struct lookup_field_info
*) data
;
980 tree type
= BINFO_TYPE (binfo
);
981 tree nval
= NULL_TREE
;
983 /* If this is a dependent base, don't look in it. */
984 if (BINFO_DEPENDENT_BASE_P (binfo
))
987 /* If this base class is hidden by the best-known value so far, we
988 don't need to look. */
989 if (lfi
->rval_binfo
&& BINFO_INHERITANCE_CHAIN (binfo
) == lfi
->rval_binfo
990 && !BINFO_VIRTUAL_P (binfo
))
991 return dfs_skip_bases
;
993 nval
= get_class_binding (type
, lfi
->name
, lfi
->want_type
);
995 /* If we're looking up a type (as with an elaborated type specifier)
996 we ignore all non-types we find. */
997 if (lfi
->want_type
&& nval
&& !DECL_DECLARES_TYPE_P (nval
))
1000 if (CLASSTYPE_NESTED_UTDS (type
))
1001 if (binding_entry e
= binding_table_find (CLASSTYPE_NESTED_UTDS (type
),
1003 nval
= TYPE_MAIN_DECL (e
->type
);
1006 /* If there is no declaration with the indicated name in this type,
1007 then there's nothing to do. */
1011 /* If the lookup already found a match, and the new value doesn't
1012 hide the old one, we might have an ambiguity. */
1014 && !is_subobject_of_p (lfi
->rval_binfo
, binfo
))
1017 if (nval
== lfi
->rval
&& shared_member_p (nval
))
1018 /* The two things are really the same. */
1020 else if (is_subobject_of_p (binfo
, lfi
->rval_binfo
))
1021 /* The previous value hides the new one. */
1025 /* We have a real ambiguity. We keep a chain of all the
1027 if (!lfi
->ambiguous
&& lfi
->rval
)
1029 /* This is the first time we noticed an ambiguity. Add
1030 what we previously thought was a reasonable candidate
1032 lfi
->ambiguous
= tree_cons (NULL_TREE
, lfi
->rval
, NULL_TREE
);
1033 TREE_TYPE (lfi
->ambiguous
) = error_mark_node
;
1036 /* Add the new value. */
1037 lfi
->ambiguous
= tree_cons (NULL_TREE
, nval
, lfi
->ambiguous
);
1038 TREE_TYPE (lfi
->ambiguous
) = error_mark_node
;
1039 lfi
->errstr
= G_("request for member %qD is ambiguous");
1045 lfi
->rval_binfo
= binfo
;
1049 /* Don't look for constructors or destructors in base classes. */
1050 if (IDENTIFIER_CDTOR_P (lfi
->name
))
1051 return dfs_skip_bases
;
1055 /* Return a "baselink" with BASELINK_BINFO, BASELINK_ACCESS_BINFO,
1056 BASELINK_FUNCTIONS, and BASELINK_OPTYPE set to BINFO, ACCESS_BINFO,
1057 FUNCTIONS, and OPTYPE respectively. */
1060 build_baselink (tree binfo
, tree access_binfo
, tree functions
, tree optype
)
1064 gcc_assert (OVL_P (functions
) || TREE_CODE (functions
) == TEMPLATE_ID_EXPR
);
1065 gcc_assert (!optype
|| TYPE_P (optype
));
1066 gcc_assert (TREE_TYPE (functions
));
1068 baselink
= make_node (BASELINK
);
1069 TREE_TYPE (baselink
) = TREE_TYPE (functions
);
1070 BASELINK_BINFO (baselink
) = binfo
;
1071 BASELINK_ACCESS_BINFO (baselink
) = access_binfo
;
1072 BASELINK_FUNCTIONS (baselink
) = functions
;
1073 BASELINK_OPTYPE (baselink
) = optype
;
1078 /* Look for a member named NAME in an inheritance lattice dominated by
1079 XBASETYPE. If PROTECT is 0 or two, we do not check access. If it
1080 is 1, we enforce accessibility. If PROTECT is zero, then, for an
1081 ambiguous lookup, we return NULL. If PROTECT is 1, we issue error
1082 messages about inaccessible or ambiguous lookup. If PROTECT is 2,
1083 we return a TREE_LIST whose TREE_TYPE is error_mark_node and whose
1084 TREE_VALUEs are the list of ambiguous candidates.
1086 WANT_TYPE is 1 when we should only return TYPE_DECLs.
1088 If nothing can be found return NULL_TREE and do not issue an error.
1090 If non-NULL, failure information is written back to AFI. */
1093 lookup_member (tree xbasetype
, tree name
, int protect
, bool want_type
,
1094 tsubst_flags_t complain
, access_failure_info
*afi
)
1096 tree rval
, rval_binfo
= NULL_TREE
;
1097 tree type
= NULL_TREE
, basetype_path
= NULL_TREE
;
1098 struct lookup_field_info lfi
;
1100 /* rval_binfo is the binfo associated with the found member, note,
1101 this can be set with useful information, even when rval is not
1102 set, because it must deal with ALL members, not just non-function
1103 members. It is used for ambiguity checking and the hidden
1104 checks. Whereas rval is only set if a proper (not hidden)
1105 non-function member is found. */
1107 const char *errstr
= 0;
1109 if (name
== error_mark_node
1110 || xbasetype
== NULL_TREE
1111 || xbasetype
== error_mark_node
)
1114 gcc_assert (identifier_p (name
));
1116 if (TREE_CODE (xbasetype
) == TREE_BINFO
)
1118 type
= BINFO_TYPE (xbasetype
);
1119 basetype_path
= xbasetype
;
1123 if (!RECORD_OR_UNION_CODE_P (TREE_CODE (xbasetype
)))
1126 xbasetype
= NULL_TREE
;
1129 type
= complete_type (type
);
1131 /* Make sure we're looking for a member of the current instantiation in the
1132 right partial specialization. */
1133 if (dependent_type_p (type
))
1134 if (tree t
= currently_open_class (type
))
1138 basetype_path
= TYPE_BINFO (type
);
1143 memset (&lfi
, 0, sizeof (lfi
));
1146 lfi
.want_type
= want_type
;
1147 dfs_walk_all (basetype_path
, &lookup_field_r
, NULL
, &lfi
);
1149 rval_binfo
= lfi
.rval_binfo
;
1151 type
= BINFO_TYPE (rval_binfo
);
1152 errstr
= lfi
.errstr
;
1154 /* If we are not interested in ambiguities, don't report them;
1155 just return NULL_TREE. */
1156 if (!protect
&& lfi
.ambiguous
)
1162 return lfi
.ambiguous
;
1169 In the case of overloaded function names, access control is
1170 applied to the function selected by overloaded resolution.
1172 We cannot check here, even if RVAL is only a single non-static
1173 member function, since we do not know what the "this" pointer
1176 class A { protected: void f(); };
1177 class B : public A {
1184 only the first call to "f" is valid. However, if the function is
1185 static, we can check. */
1187 && !really_overloaded_fn (rval
))
1189 tree decl
= is_overloaded_fn (rval
) ? get_first_fn (rval
) : rval
;
1190 decl
= strip_using_decl (decl
);
1191 /* A dependent USING_DECL will be checked after tsubsting. */
1192 if (TREE_CODE (decl
) != USING_DECL
1193 && !DECL_NONSTATIC_MEMBER_FUNCTION_P (decl
)
1194 && !perform_or_defer_access_check (basetype_path
, decl
, decl
,
1196 rval
= error_mark_node
;
1199 if (errstr
&& protect
)
1201 if (complain
& tf_error
)
1203 error (errstr
, name
, type
);
1205 print_candidates (lfi
.ambiguous
);
1207 rval
= error_mark_node
;
1210 if (rval
&& is_overloaded_fn (rval
))
1211 rval
= build_baselink (rval_binfo
, basetype_path
, rval
,
1212 (IDENTIFIER_CONV_OP_P (name
)
1213 ? TREE_TYPE (name
): NULL_TREE
));
1217 /* Helper class for lookup_member_fuzzy. */
1219 class lookup_field_fuzzy_info
1222 lookup_field_fuzzy_info (bool want_type_p
) :
1223 m_want_type_p (want_type_p
), m_candidates () {}
1225 void fuzzy_lookup_field (tree type
);
1227 /* If true, we are looking for types, not data members. */
1229 /* The result: a vec of identifiers. */
1230 auto_vec
<tree
> m_candidates
;
1233 /* Locate all fields within TYPE, append them to m_candidates. */
1236 lookup_field_fuzzy_info::fuzzy_lookup_field (tree type
)
1238 if (!CLASS_TYPE_P (type
))
1241 for (tree field
= TYPE_FIELDS (type
); field
; field
= DECL_CHAIN (field
))
1243 if (m_want_type_p
&& !DECL_DECLARES_TYPE_P (field
))
1246 if (!DECL_NAME (field
))
1249 if (is_lambda_ignored_entity (field
))
1252 m_candidates
.safe_push (DECL_NAME (field
));
1257 /* Helper function for lookup_member_fuzzy, called via dfs_walk_all
1258 DATA is really a lookup_field_fuzzy_info. Look for a field with
1259 the name indicated there in BINFO. Gathers pertinent identifiers into
1263 lookup_field_fuzzy_r (tree binfo
, void *data
)
1265 lookup_field_fuzzy_info
*lffi
= (lookup_field_fuzzy_info
*) data
;
1266 tree type
= BINFO_TYPE (binfo
);
1268 lffi
->fuzzy_lookup_field (type
);
1273 /* Like lookup_member, but try to find the closest match for NAME,
1274 rather than an exact match, and return an identifier (or NULL_TREE).
1278 lookup_member_fuzzy (tree xbasetype
, tree name
, bool want_type_p
)
1280 tree type
= NULL_TREE
, basetype_path
= NULL_TREE
;
1281 class lookup_field_fuzzy_info
lffi (want_type_p
);
1283 /* rval_binfo is the binfo associated with the found member, note,
1284 this can be set with useful information, even when rval is not
1285 set, because it must deal with ALL members, not just non-function
1286 members. It is used for ambiguity checking and the hidden
1287 checks. Whereas rval is only set if a proper (not hidden)
1288 non-function member is found. */
1290 if (name
== error_mark_node
1291 || xbasetype
== NULL_TREE
1292 || xbasetype
== error_mark_node
)
1295 gcc_assert (identifier_p (name
));
1297 if (TREE_CODE (xbasetype
) == TREE_BINFO
)
1299 type
= BINFO_TYPE (xbasetype
);
1300 basetype_path
= xbasetype
;
1304 if (!RECORD_OR_UNION_CODE_P (TREE_CODE (xbasetype
)))
1307 xbasetype
= NULL_TREE
;
1310 type
= complete_type (type
);
1312 /* Make sure we're looking for a member of the current instantiation in the
1313 right partial specialization. */
1314 if (flag_concepts
&& dependent_type_p (type
))
1315 type
= currently_open_class (type
);
1318 basetype_path
= TYPE_BINFO (type
);
1323 /* Populate lffi.m_candidates. */
1324 dfs_walk_all (basetype_path
, &lookup_field_fuzzy_r
, NULL
, &lffi
);
1326 return find_closest_identifier (name
, &lffi
.m_candidates
);
1329 /* Like lookup_member, except that if we find a function member we
1330 return NULL_TREE. */
1333 lookup_field (tree xbasetype
, tree name
, int protect
, bool want_type
)
1335 tree rval
= lookup_member (xbasetype
, name
, protect
, want_type
,
1336 tf_warning_or_error
);
1338 /* Ignore functions, but propagate the ambiguity list. */
1339 if (!error_operand_p (rval
)
1340 && (rval
&& BASELINK_P (rval
)))
1346 /* Like lookup_member, except that if we find a non-function member we
1347 return NULL_TREE. */
1350 lookup_fnfields (tree xbasetype
, tree name
, int protect
)
1352 tree rval
= lookup_member (xbasetype
, name
, protect
, /*want_type=*/false,
1353 tf_warning_or_error
);
1355 /* Ignore non-functions, but propagate the ambiguity list. */
1356 if (!error_operand_p (rval
)
1357 && (rval
&& !BASELINK_P (rval
)))
1363 /* DECL is the result of a qualified name lookup. QUALIFYING_SCOPE is
1364 the class or namespace used to qualify the name. CONTEXT_CLASS is
1365 the class corresponding to the object in which DECL will be used.
1366 Return a possibly modified version of DECL that takes into account
1369 In particular, consider an expression like `B::m' in the context of
1370 a derived class `D'. If `B::m' has been resolved to a BASELINK,
1371 then the most derived class indicated by the BASELINK_BINFO will be
1372 `B', not `D'. This function makes that adjustment. */
1375 adjust_result_of_qualified_name_lookup (tree decl
,
1376 tree qualifying_scope
,
1379 if (context_class
&& context_class
!= error_mark_node
1380 && CLASS_TYPE_P (context_class
)
1381 && CLASS_TYPE_P (qualifying_scope
)
1382 && DERIVED_FROM_P (qualifying_scope
, context_class
)
1383 && BASELINK_P (decl
))
1387 /* Look for the QUALIFYING_SCOPE as a base of the CONTEXT_CLASS.
1388 Because we do not yet know which function will be chosen by
1389 overload resolution, we cannot yet check either accessibility
1390 or ambiguity -- in either case, the choice of a static member
1391 function might make the usage valid. */
1392 base
= lookup_base (context_class
, qualifying_scope
,
1393 ba_unique
, NULL
, tf_none
);
1394 if (base
&& base
!= error_mark_node
)
1396 BASELINK_ACCESS_BINFO (decl
) = base
;
1398 = lookup_base (base
, BINFO_TYPE (BASELINK_BINFO (decl
)),
1399 ba_unique
, NULL
, tf_none
);
1400 if (decl_binfo
&& decl_binfo
!= error_mark_node
)
1401 BASELINK_BINFO (decl
) = decl_binfo
;
1405 if (BASELINK_P (decl
))
1406 BASELINK_QUALIFIED_P (decl
) = true;
1412 /* Walk the class hierarchy within BINFO, in a depth-first traversal.
1413 PRE_FN is called in preorder, while POST_FN is called in postorder.
1414 If PRE_FN returns DFS_SKIP_BASES, child binfos will not be
1415 walked. If PRE_FN or POST_FN returns a different non-NULL value,
1416 that value is immediately returned and the walk is terminated. One
1417 of PRE_FN and POST_FN can be NULL. At each node, PRE_FN and
1418 POST_FN are passed the binfo to examine and the caller's DATA
1419 value. All paths are walked, thus virtual and morally virtual
1420 binfos can be multiply walked. */
1423 dfs_walk_all (tree binfo
, tree (*pre_fn
) (tree
, void *),
1424 tree (*post_fn
) (tree
, void *), void *data
)
1430 /* Call the pre-order walking function. */
1433 rval
= pre_fn (binfo
, data
);
1436 if (rval
== dfs_skip_bases
)
1442 /* Find the next child binfo to walk. */
1443 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1445 rval
= dfs_walk_all (base_binfo
, pre_fn
, post_fn
, data
);
1451 /* Call the post-order walking function. */
1454 rval
= post_fn (binfo
, data
);
1455 gcc_assert (rval
!= dfs_skip_bases
);
1462 /* Worker for dfs_walk_once. This behaves as dfs_walk_all, except
1463 that binfos are walked at most once. */
1466 dfs_walk_once_r (tree binfo
, tree (*pre_fn
) (tree
, void *),
1467 tree (*post_fn
) (tree
, void *), hash_set
<tree
> *pset
,
1474 /* Call the pre-order walking function. */
1477 rval
= pre_fn (binfo
, data
);
1480 if (rval
== dfs_skip_bases
)
1487 /* Find the next child binfo to walk. */
1488 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1490 if (BINFO_VIRTUAL_P (base_binfo
))
1491 if (pset
->add (base_binfo
))
1494 rval
= dfs_walk_once_r (base_binfo
, pre_fn
, post_fn
, pset
, data
);
1500 /* Call the post-order walking function. */
1503 rval
= post_fn (binfo
, data
);
1504 gcc_assert (rval
!= dfs_skip_bases
);
1511 /* Like dfs_walk_all, except that binfos are not multiply walked. For
1512 non-diamond shaped hierarchies this is the same as dfs_walk_all.
1513 For diamond shaped hierarchies we must mark the virtual bases, to
1514 avoid multiple walks. */
1517 dfs_walk_once (tree binfo
, tree (*pre_fn
) (tree
, void *),
1518 tree (*post_fn
) (tree
, void *), void *data
)
1520 static int active
= 0; /* We must not be called recursively. */
1523 gcc_assert (pre_fn
|| post_fn
);
1524 gcc_assert (!active
);
1527 if (!CLASSTYPE_DIAMOND_SHAPED_P (BINFO_TYPE (binfo
)))
1528 /* We are not diamond shaped, and therefore cannot encounter the
1529 same binfo twice. */
1530 rval
= dfs_walk_all (binfo
, pre_fn
, post_fn
, data
);
1533 hash_set
<tree
> pset
;
1534 rval
= dfs_walk_once_r (binfo
, pre_fn
, post_fn
, &pset
, data
);
1542 /* Worker function for dfs_walk_once_accessible. Behaves like
1543 dfs_walk_once_r, except (a) FRIENDS_P is true if special
1544 access given by the current context should be considered, (b) ONCE
1545 indicates whether bases should be marked during traversal. */
1548 dfs_walk_once_accessible_r (tree binfo
, bool friends_p
, hash_set
<tree
> *pset
,
1549 tree (*pre_fn
) (tree
, void *),
1550 tree (*post_fn
) (tree
, void *), void *data
)
1552 tree rval
= NULL_TREE
;
1556 /* Call the pre-order walking function. */
1559 rval
= pre_fn (binfo
, data
);
1562 if (rval
== dfs_skip_bases
)
1569 /* Find the next child binfo to walk. */
1570 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
1572 bool mark
= pset
&& BINFO_VIRTUAL_P (base_binfo
);
1574 if (mark
&& pset
->contains (base_binfo
))
1577 /* If the base is inherited via private or protected
1578 inheritance, then we can't see it, unless we are a friend of
1579 the current binfo. */
1580 if (BINFO_BASE_ACCESS (binfo
, ix
) != access_public_node
)
1585 scope
= current_scope ();
1587 || TREE_CODE (scope
) == NAMESPACE_DECL
1588 || !is_friend (BINFO_TYPE (binfo
), scope
))
1593 pset
->add (base_binfo
);
1595 rval
= dfs_walk_once_accessible_r (base_binfo
, friends_p
, pset
,
1596 pre_fn
, post_fn
, data
);
1602 /* Call the post-order walking function. */
1605 rval
= post_fn (binfo
, data
);
1606 gcc_assert (rval
!= dfs_skip_bases
);
1613 /* Like dfs_walk_once except that only accessible bases are walked.
1614 FRIENDS_P indicates whether friendship of the local context
1615 should be considered when determining accessibility. */
1618 dfs_walk_once_accessible (tree binfo
, bool friends_p
,
1619 tree (*pre_fn
) (tree
, void *),
1620 tree (*post_fn
) (tree
, void *), void *data
)
1622 hash_set
<tree
> *pset
= NULL
;
1623 if (CLASSTYPE_DIAMOND_SHAPED_P (BINFO_TYPE (binfo
)))
1624 pset
= new hash_set
<tree
>;
1625 tree rval
= dfs_walk_once_accessible_r (binfo
, friends_p
, pset
,
1626 pre_fn
, post_fn
, data
);
1633 /* Return true iff the code of T is CODE, and it has compatible
1637 matches_code_and_type_p (tree t
, enum tree_code code
, tree type
)
1639 if (TREE_CODE (t
) != code
)
1641 if (!cxx_types_compatible_p (TREE_TYPE (t
), type
))
1646 /* Subroutine of direct_accessor_p and reference_accessor_p.
1647 Determine if COMPONENT_REF is a simple field lookup of this->FIELD_DECL.
1648 We expect a tree of the form:
1653 <field_decl (FIELD_DECL)>>>. */
1656 field_access_p (tree component_ref
, tree field_decl
, tree field_type
)
1658 if (!matches_code_and_type_p (component_ref
, COMPONENT_REF
, field_type
))
1661 tree indirect_ref
= TREE_OPERAND (component_ref
, 0);
1662 if (!INDIRECT_REF_P (indirect_ref
))
1665 tree ptr
= STRIP_NOPS (TREE_OPERAND (indirect_ref
, 0));
1666 if (!is_this_parameter (ptr
))
1669 /* Must access the correct field. */
1670 if (TREE_OPERAND (component_ref
, 1) != field_decl
)
1675 /* Subroutine of field_accessor_p.
1677 Assuming that INIT_EXPR has already had its code and type checked,
1678 determine if it is a simple accessor for FIELD_DECL
1679 (of type FIELD_TYPE).
1681 Specifically, a simple accessor within struct S of the form:
1682 T get_field () { return m_field; }
1683 should have a constexpr_fn_retval (saved_tree) of the form:
1691 <field_decl (FIELD_DECL)>>>>>. */
1694 direct_accessor_p (tree init_expr
, tree field_decl
, tree field_type
)
1696 tree result_decl
= TREE_OPERAND (init_expr
, 0);
1697 if (!matches_code_and_type_p (result_decl
, RESULT_DECL
, field_type
))
1700 tree component_ref
= STRIP_NOPS (TREE_OPERAND (init_expr
, 1));
1701 if (!field_access_p (component_ref
, field_decl
, field_type
))
1707 /* Subroutine of field_accessor_p.
1709 Assuming that INIT_EXPR has already had its code and type checked,
1710 determine if it is a "reference" accessor for FIELD_DECL
1711 (of type FIELD_REFERENCE_TYPE).
1713 Specifically, a simple accessor within struct S of the form:
1714 T& get_field () { return m_field; }
1715 should have a constexpr_fn_retval (saved_tree) of the form:
1724 <field (FIELD_DECL)>>>>>>. */
1726 reference_accessor_p (tree init_expr
, tree field_decl
, tree field_type
,
1727 tree field_reference_type
)
1729 tree result_decl
= TREE_OPERAND (init_expr
, 0);
1730 if (!matches_code_and_type_p (result_decl
, RESULT_DECL
, field_reference_type
))
1733 tree field_pointer_type
= build_pointer_type (field_type
);
1734 tree addr_expr
= STRIP_NOPS (TREE_OPERAND (init_expr
, 1));
1735 if (!matches_code_and_type_p (addr_expr
, ADDR_EXPR
, field_pointer_type
))
1738 tree component_ref
= STRIP_NOPS (TREE_OPERAND (addr_expr
, 0));
1740 if (!field_access_p (component_ref
, field_decl
, field_type
))
1746 /* Return true if FN is an accessor method for FIELD_DECL.
1747 i.e. a method of the form { return FIELD; }, with no
1750 If CONST_P, then additionally require that FN be a const
1754 field_accessor_p (tree fn
, tree field_decl
, bool const_p
)
1756 if (TREE_CODE (fn
) != FUNCTION_DECL
)
1759 /* We don't yet support looking up static data, just fields. */
1760 if (TREE_CODE (field_decl
) != FIELD_DECL
)
1763 tree fntype
= TREE_TYPE (fn
);
1764 if (TREE_CODE (fntype
) != METHOD_TYPE
)
1767 /* If the field is accessed via a const "this" argument, verify
1768 that the "this" parameter is const. */
1771 tree this_class
= class_of_this_parm (fntype
);
1772 if (!TYPE_READONLY (this_class
))
1776 tree saved_tree
= DECL_SAVED_TREE (fn
);
1778 if (saved_tree
== NULL_TREE
)
1781 /* Attempt to extract a single return value from the function,
1783 tree retval
= constexpr_fn_retval (saved_tree
);
1784 if (retval
== NULL_TREE
|| retval
== error_mark_node
)
1786 /* Require an INIT_EXPR. */
1787 if (TREE_CODE (retval
) != INIT_EXPR
)
1789 tree init_expr
= retval
;
1791 /* Determine if this is a simple accessor within struct S of the form:
1792 T get_field () { return m_field; }. */
1793 tree field_type
= TREE_TYPE (field_decl
);
1794 if (cxx_types_compatible_p (TREE_TYPE (init_expr
), field_type
))
1795 return direct_accessor_p (init_expr
, field_decl
, field_type
);
1797 /* Failing that, determine if it is an accessor of the form:
1798 T& get_field () { return m_field; }. */
1799 tree field_reference_type
= cp_build_reference_type (field_type
, false);
1800 if (cxx_types_compatible_p (TREE_TYPE (init_expr
), field_reference_type
))
1801 return reference_accessor_p (init_expr
, field_decl
, field_type
,
1802 field_reference_type
);
1807 /* Callback data for dfs_locate_field_accessor_pre. */
1809 class locate_field_data
1812 locate_field_data (tree field_decl_
, bool const_p_
)
1813 : field_decl (field_decl_
), const_p (const_p_
) {}
1819 /* Return a FUNCTION_DECL that is an "accessor" method for DATA, a FIELD_DECL,
1820 callable via binfo, if one exists, otherwise return NULL_TREE.
1822 Callback for dfs_walk_once_accessible for use within
1823 locate_field_accessor. */
1826 dfs_locate_field_accessor_pre (tree binfo
, void *data
)
1828 locate_field_data
*lfd
= (locate_field_data
*)data
;
1829 tree type
= BINFO_TYPE (binfo
);
1831 vec
<tree
, va_gc
> *member_vec
;
1835 if (!CLASS_TYPE_P (type
))
1838 member_vec
= CLASSTYPE_MEMBER_VEC (type
);
1842 for (i
= 0; vec_safe_iterate (member_vec
, i
, &fn
); ++i
)
1844 if (field_accessor_p (fn
, lfd
->field_decl
, lfd
->const_p
))
1850 /* Return a FUNCTION_DECL that is an "accessor" method for FIELD_DECL,
1851 callable via BASETYPE_PATH, if one exists, otherwise return NULL_TREE. */
1854 locate_field_accessor (tree basetype_path
, tree field_decl
, bool const_p
)
1856 if (TREE_CODE (basetype_path
) != TREE_BINFO
)
1859 /* Walk the hierarchy, looking for a method of some base class that allows
1860 access to the field. */
1861 locate_field_data
lfd (field_decl
, const_p
);
1862 return dfs_walk_once_accessible (basetype_path
, /*friends=*/true,
1863 dfs_locate_field_accessor_pre
,
1867 /* Check throw specifier of OVERRIDER is at least as strict as
1868 the one of BASEFN. */
1871 maybe_check_overriding_exception_spec (tree overrider
, tree basefn
)
1873 maybe_instantiate_noexcept (basefn
);
1874 maybe_instantiate_noexcept (overrider
);
1875 tree base_throw
= TYPE_RAISES_EXCEPTIONS (TREE_TYPE (basefn
));
1876 tree over_throw
= TYPE_RAISES_EXCEPTIONS (TREE_TYPE (overrider
));
1878 if (DECL_INVALID_OVERRIDER_P (overrider
))
1881 /* Can't check this yet. Pretend this is fine and let
1882 noexcept_override_late_checks check this later. */
1883 if (UNPARSED_NOEXCEPT_SPEC_P (base_throw
)
1884 || UNPARSED_NOEXCEPT_SPEC_P (over_throw
))
1887 if (!comp_except_specs (base_throw
, over_throw
, ce_derived
))
1889 auto_diagnostic_group d
;
1890 error ("looser exception specification on overriding virtual function "
1891 "%q+#F", overrider
);
1892 inform (DECL_SOURCE_LOCATION (basefn
),
1893 "overridden function is %q#F", basefn
);
1894 DECL_INVALID_OVERRIDER_P (overrider
) = 1;
1900 /* Check that virtual overrider OVERRIDER is acceptable for base function
1901 BASEFN. Issue diagnostic, and return zero, if unacceptable. */
1904 check_final_overrider (tree overrider
, tree basefn
)
1906 tree over_type
= TREE_TYPE (overrider
);
1907 tree base_type
= TREE_TYPE (basefn
);
1908 tree over_return
= fndecl_declared_return_type (overrider
);
1909 tree base_return
= fndecl_declared_return_type (basefn
);
1913 if (DECL_INVALID_OVERRIDER_P (overrider
))
1916 if (same_type_p (base_return
, over_return
))
1918 else if ((CLASS_TYPE_P (over_return
) && CLASS_TYPE_P (base_return
))
1919 || (TREE_CODE (base_return
) == TREE_CODE (over_return
)
1920 && INDIRECT_TYPE_P (base_return
)))
1922 /* Potentially covariant. */
1923 unsigned base_quals
, over_quals
;
1925 fail
= !INDIRECT_TYPE_P (base_return
);
1928 fail
= cp_type_quals (base_return
) != cp_type_quals (over_return
);
1930 base_return
= TREE_TYPE (base_return
);
1931 over_return
= TREE_TYPE (over_return
);
1933 base_quals
= cp_type_quals (base_return
);
1934 over_quals
= cp_type_quals (over_return
);
1936 if ((base_quals
& over_quals
) != over_quals
)
1939 if (CLASS_TYPE_P (base_return
) && CLASS_TYPE_P (over_return
))
1941 /* Strictly speaking, the standard requires the return type to be
1942 complete even if it only differs in cv-quals, but that seems
1943 like a bug in the wording. */
1944 if (!same_type_ignoring_top_level_qualifiers_p (base_return
,
1947 tree binfo
= lookup_base (over_return
, base_return
,
1948 ba_check
, NULL
, tf_none
);
1950 if (!binfo
|| binfo
== error_mark_node
)
1954 else if (can_convert_standard (TREE_TYPE (base_type
),
1955 TREE_TYPE (over_type
),
1956 tf_warning_or_error
))
1957 /* GNU extension, allow trivial pointer conversions such as
1958 converting to void *, or qualification conversion. */
1960 auto_diagnostic_group d
;
1961 if (pedwarn (DECL_SOURCE_LOCATION (overrider
), 0,
1962 "invalid covariant return type for %q#D", overrider
))
1963 inform (DECL_SOURCE_LOCATION (basefn
),
1964 "overridden function is %q#D", basefn
);
1977 auto_diagnostic_group d
;
1978 error ("invalid covariant return type for %q+#D", overrider
);
1979 inform (DECL_SOURCE_LOCATION (basefn
),
1980 "overridden function is %q#D", basefn
);
1984 auto_diagnostic_group d
;
1985 error ("conflicting return type specified for %q+#D", overrider
);
1986 inform (DECL_SOURCE_LOCATION (basefn
),
1987 "overridden function is %q#D", basefn
);
1989 DECL_INVALID_OVERRIDER_P (overrider
) = 1;
1993 if (!maybe_check_overriding_exception_spec (overrider
, basefn
))
1996 /* Check for conflicting type attributes. But leave transaction_safe for
1997 set_one_vmethod_tm_attributes. */
1998 if (!comp_type_attributes (over_type
, base_type
)
1999 && !tx_safe_fn_type_p (base_type
)
2000 && !tx_safe_fn_type_p (over_type
))
2002 auto_diagnostic_group d
;
2003 error ("conflicting type attributes specified for %q+#D", overrider
);
2004 inform (DECL_SOURCE_LOCATION (basefn
),
2005 "overridden function is %q#D", basefn
);
2006 DECL_INVALID_OVERRIDER_P (overrider
) = 1;
2010 /* A function declared transaction_safe_dynamic that overrides a function
2011 declared transaction_safe (but not transaction_safe_dynamic) is
2013 if (tx_safe_fn_type_p (base_type
)
2014 && lookup_attribute ("transaction_safe_dynamic",
2015 DECL_ATTRIBUTES (overrider
))
2016 && !lookup_attribute ("transaction_safe_dynamic",
2017 DECL_ATTRIBUTES (basefn
)))
2019 auto_diagnostic_group d
;
2020 error_at (DECL_SOURCE_LOCATION (overrider
),
2021 "%qD declared %<transaction_safe_dynamic%>", overrider
);
2022 inform (DECL_SOURCE_LOCATION (basefn
),
2023 "overriding %qD declared %<transaction_safe%>", basefn
);
2026 if (DECL_DELETED_FN (basefn
) != DECL_DELETED_FN (overrider
))
2028 if (DECL_DELETED_FN (overrider
))
2030 auto_diagnostic_group d
;
2031 error ("deleted function %q+D overriding non-deleted function",
2033 inform (DECL_SOURCE_LOCATION (basefn
),
2034 "overridden function is %qD", basefn
);
2035 maybe_explain_implicit_delete (overrider
);
2039 auto_diagnostic_group d
;
2040 error ("non-deleted function %q+D overriding deleted function",
2042 inform (DECL_SOURCE_LOCATION (basefn
),
2043 "overridden function is %qD", basefn
);
2047 if (DECL_FINAL_P (basefn
))
2049 auto_diagnostic_group d
;
2050 error ("virtual function %q+D overriding final function", overrider
);
2051 inform (DECL_SOURCE_LOCATION (basefn
),
2052 "overridden function is %qD", basefn
);
2058 /* Given a class TYPE, and a function decl FNDECL, look for
2059 virtual functions in TYPE's hierarchy which FNDECL overrides.
2060 We do not look in TYPE itself, only its bases.
2062 Returns nonzero, if we find any. Set FNDECL's DECL_VIRTUAL_P, if we
2063 find that it overrides anything.
2065 We check that every function which is overridden, is correctly
2069 look_for_overrides (tree type
, tree fndecl
)
2071 tree binfo
= TYPE_BINFO (type
);
2076 /* A constructor for a class T does not override a function T
2078 if (DECL_CONSTRUCTOR_P (fndecl
))
2081 for (ix
= 0; BINFO_BASE_ITERATE (binfo
, ix
, base_binfo
); ix
++)
2083 tree basetype
= BINFO_TYPE (base_binfo
);
2085 if (TYPE_POLYMORPHIC_P (basetype
))
2086 found
+= look_for_overrides_r (basetype
, fndecl
);
2091 /* Look in TYPE for virtual functions with the same signature as
2095 look_for_overrides_here (tree type
, tree fndecl
)
2097 tree ovl
= get_class_binding (type
, DECL_NAME (fndecl
));
2099 for (ovl_iterator
iter (ovl
); iter
; ++iter
)
2103 if (!DECL_VIRTUAL_P (fn
))
2104 /* Not a virtual. */;
2105 else if (DECL_CONTEXT (fn
) != type
)
2106 /* Introduced with a using declaration. */;
2107 else if (DECL_STATIC_FUNCTION_P (fndecl
))
2109 tree btypes
= TYPE_ARG_TYPES (TREE_TYPE (fn
));
2110 tree dtypes
= TYPE_ARG_TYPES (TREE_TYPE (fndecl
));
2111 if (compparms (TREE_CHAIN (btypes
), dtypes
))
2114 else if (same_signature_p (fndecl
, fn
))
2121 /* Look in TYPE for virtual functions overridden by FNDECL. Check both
2122 TYPE itself and its bases. */
2125 look_for_overrides_r (tree type
, tree fndecl
)
2127 tree fn
= look_for_overrides_here (type
, fndecl
);
2130 if (DECL_STATIC_FUNCTION_P (fndecl
))
2132 /* A static member function cannot match an inherited
2133 virtual member function. */
2134 auto_diagnostic_group d
;
2135 error ("%q+#D cannot be declared", fndecl
);
2136 error (" since %q+#D declared in base class", fn
);
2140 /* It's definitely virtual, even if not explicitly set. */
2141 DECL_VIRTUAL_P (fndecl
) = 1;
2142 check_final_overrider (fndecl
, fn
);
2147 /* We failed to find one declared in this class. Look in its bases. */
2148 return look_for_overrides (type
, fndecl
);
2151 /* Called via dfs_walk from dfs_get_pure_virtuals. */
2154 dfs_get_pure_virtuals (tree binfo
, void *data
)
2156 tree type
= (tree
) data
;
2158 /* We're not interested in primary base classes; the derived class
2159 of which they are a primary base will contain the information we
2161 if (!BINFO_PRIMARY_P (binfo
))
2165 for (virtuals
= BINFO_VIRTUALS (binfo
);
2167 virtuals
= TREE_CHAIN (virtuals
))
2168 if (DECL_PURE_VIRTUAL_P (BV_FN (virtuals
)))
2169 vec_safe_push (CLASSTYPE_PURE_VIRTUALS (type
), BV_FN (virtuals
));
2175 /* Set CLASSTYPE_PURE_VIRTUALS for TYPE. */
2178 get_pure_virtuals (tree type
)
2180 /* Clear the CLASSTYPE_PURE_VIRTUALS list; whatever is already there
2181 is going to be overridden. */
2182 CLASSTYPE_PURE_VIRTUALS (type
) = NULL
;
2183 /* Now, run through all the bases which are not primary bases, and
2184 collect the pure virtual functions. We look at the vtable in
2185 each class to determine what pure virtual functions are present.
2186 (A primary base is not interesting because the derived class of
2187 which it is a primary base will contain vtable entries for the
2188 pure virtuals in the base class. */
2189 dfs_walk_once (TYPE_BINFO (type
), NULL
, dfs_get_pure_virtuals
, type
);
2192 /* Debug info for C++ classes can get very large; try to avoid
2193 emitting it everywhere.
2195 Note that this optimization wins even when the target supports
2196 BINCL (if only slightly), and reduces the amount of work for the
2200 maybe_suppress_debug_info (tree t
)
2202 if (write_symbols
== NO_DEBUG
)
2205 /* We might have set this earlier in cp_finish_decl. */
2206 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t
)) = 0;
2208 /* Always emit the information for each class every time. */
2209 if (flag_emit_class_debug_always
)
2212 /* If we already know how we're handling this class, handle debug info
2214 if (CLASSTYPE_INTERFACE_KNOWN (t
))
2216 if (CLASSTYPE_INTERFACE_ONLY (t
))
2217 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t
)) = 1;
2218 /* else don't set it. */
2220 /* If the class has a vtable, write out the debug info along with
2222 else if (TYPE_CONTAINS_VPTR_P (t
))
2223 TYPE_DECL_SUPPRESS_DEBUG (TYPE_MAIN_DECL (t
)) = 1;
2225 /* Otherwise, just emit the debug info normally. */
2228 /* Note that we want debugging information for a base class of a class
2229 whose vtable is being emitted. Normally, this would happen because
2230 calling the constructor for a derived class implies calling the
2231 constructors for all bases, which involve initializing the
2232 appropriate vptr with the vtable for the base class; but in the
2233 presence of optimization, this initialization may be optimized
2234 away, so we tell finish_vtable_vardecl that we want the debugging
2235 information anyway. */
2238 dfs_debug_mark (tree binfo
, void * /*data*/)
2240 tree t
= BINFO_TYPE (binfo
);
2242 if (CLASSTYPE_DEBUG_REQUESTED (t
))
2243 return dfs_skip_bases
;
2245 CLASSTYPE_DEBUG_REQUESTED (t
) = 1;
2250 /* Write out the debugging information for TYPE, whose vtable is being
2251 emitted. Also walk through our bases and note that we want to
2252 write out information for them. This avoids the problem of not
2253 writing any debug info for intermediate basetypes whose
2254 constructors, and thus the references to their vtables, and thus
2255 the vtables themselves, were optimized away. */
2258 note_debug_info_needed (tree type
)
2260 if (TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type
)))
2262 TYPE_DECL_SUPPRESS_DEBUG (TYPE_NAME (type
)) = 0;
2263 rest_of_type_compilation (type
, namespace_bindings_p ());
2266 dfs_walk_all (TYPE_BINFO (type
), dfs_debug_mark
, NULL
, 0);
2269 /* Helper for lookup_conversions_r. TO_TYPE is the type converted to
2270 by a conversion op in base BINFO. VIRTUAL_DEPTH is nonzero if
2271 BINFO is morally virtual, and VIRTUALNESS is nonzero if virtual
2272 bases have been encountered already in the tree walk. PARENT_CONVS
2273 is the list of lists of conversion functions that could hide CONV
2274 and OTHER_CONVS is the list of lists of conversion functions that
2275 could hide or be hidden by CONV, should virtualness be involved in
2276 the hierarchy. Merely checking the conversion op's name is not
2277 enough because two conversion operators to the same type can have
2278 different names. Return nonzero if we are visible. */
2281 check_hidden_convs (tree binfo
, int virtual_depth
, int virtualness
,
2282 tree to_type
, tree parent_convs
, tree other_convs
)
2286 /* See if we are hidden by a parent conversion. */
2287 for (level
= parent_convs
; level
; level
= TREE_CHAIN (level
))
2288 for (probe
= TREE_VALUE (level
); probe
; probe
= TREE_CHAIN (probe
))
2289 if (same_type_p (to_type
, TREE_TYPE (probe
)))
2292 if (virtual_depth
|| virtualness
)
2294 /* In a virtual hierarchy, we could be hidden, or could hide a
2295 conversion function on the other_convs list. */
2296 for (level
= other_convs
; level
; level
= TREE_CHAIN (level
))
2302 if (!(virtual_depth
|| TREE_STATIC (level
)))
2303 /* Neither is morally virtual, so cannot hide each other. */
2306 if (!TREE_VALUE (level
))
2307 /* They evaporated away already. */
2310 they_hide_us
= (virtual_depth
2311 && original_binfo (binfo
, TREE_PURPOSE (level
)));
2312 we_hide_them
= (!they_hide_us
&& TREE_STATIC (level
)
2313 && original_binfo (TREE_PURPOSE (level
), binfo
));
2315 if (!(we_hide_them
|| they_hide_us
))
2316 /* Neither is within the other, so no hiding can occur. */
2319 for (prev
= &TREE_VALUE (level
), other
= *prev
; other
;)
2321 if (same_type_p (to_type
, TREE_TYPE (other
)))
2324 /* We are hidden. */
2329 /* We hide the other one. */
2330 other
= TREE_CHAIN (other
);
2335 prev
= &TREE_CHAIN (other
);
2343 /* Helper for lookup_conversions_r. PARENT_CONVS is a list of lists
2344 of conversion functions, the first slot will be for the current
2345 binfo, if MY_CONVS is non-NULL. CHILD_CONVS is the list of lists
2346 of conversion functions from children of the current binfo,
2347 concatenated with conversions from elsewhere in the hierarchy --
2348 that list begins with OTHER_CONVS. Return a single list of lists
2349 containing only conversions from the current binfo and its
2353 split_conversions (tree my_convs
, tree parent_convs
,
2354 tree child_convs
, tree other_convs
)
2359 /* Remove the original other_convs portion from child_convs. */
2360 for (prev
= NULL
, t
= child_convs
;
2361 t
!= other_convs
; prev
= t
, t
= TREE_CHAIN (t
))
2365 TREE_CHAIN (prev
) = NULL_TREE
;
2367 child_convs
= NULL_TREE
;
2369 /* Attach the child convs to any we had at this level. */
2372 my_convs
= parent_convs
;
2373 TREE_CHAIN (my_convs
) = child_convs
;
2376 my_convs
= child_convs
;
2381 /* Worker for lookup_conversions. Lookup conversion functions in
2382 BINFO and its children. VIRTUAL_DEPTH is nonzero, if BINFO is in a
2383 morally virtual base, and VIRTUALNESS is nonzero, if we've
2384 encountered virtual bases already in the tree walk. PARENT_CONVS
2385 is a list of conversions within parent binfos. OTHER_CONVS are
2386 conversions found elsewhere in the tree. Return the conversions
2387 found within this portion of the graph in CONVS. Return nonzero if
2388 we encountered virtualness. We keep template and non-template
2389 conversions separate, to avoid unnecessary type comparisons.
2391 The located conversion functions are held in lists of lists. The
2392 TREE_VALUE of the outer list is the list of conversion functions
2393 found in a particular binfo. The TREE_PURPOSE of both the outer
2394 and inner lists is the binfo at which those conversions were
2395 found. TREE_STATIC is set for those lists within of morally
2396 virtual binfos. The TREE_VALUE of the inner list is the conversion
2397 function or overload itself. The TREE_TYPE of each inner list node
2398 is the converted-to type. */
2401 lookup_conversions_r (tree binfo
, int virtual_depth
, int virtualness
,
2402 tree parent_convs
, tree other_convs
, tree
*convs
)
2404 int my_virtualness
= 0;
2405 tree my_convs
= NULL_TREE
;
2406 tree child_convs
= NULL_TREE
;
2408 /* If we have no conversion operators, then don't look. */
2409 if (!TYPE_HAS_CONVERSION (BINFO_TYPE (binfo
)))
2416 if (BINFO_VIRTUAL_P (binfo
))
2419 /* First, locate the unhidden ones at this level. */
2420 if (tree conv
= get_class_binding (BINFO_TYPE (binfo
), conv_op_identifier
))
2421 for (ovl_iterator
iter (conv
); iter
; ++iter
)
2424 tree type
= DECL_CONV_FN_TYPE (fn
);
2426 if (TREE_CODE (fn
) != TEMPLATE_DECL
&& type_uses_auto (type
))
2429 type
= DECL_CONV_FN_TYPE (fn
);
2432 if (check_hidden_convs (binfo
, virtual_depth
, virtualness
,
2433 type
, parent_convs
, other_convs
))
2435 my_convs
= tree_cons (binfo
, fn
, my_convs
);
2436 TREE_TYPE (my_convs
) = type
;
2439 TREE_STATIC (my_convs
) = 1;
2447 parent_convs
= tree_cons (binfo
, my_convs
, parent_convs
);
2449 TREE_STATIC (parent_convs
) = 1;
2452 child_convs
= other_convs
;
2454 /* Now iterate over each base, looking for more conversions. */
2457 for (i
= 0; BINFO_BASE_ITERATE (binfo
, i
, base_binfo
); i
++)
2460 unsigned base_virtualness
;
2462 base_virtualness
= lookup_conversions_r (base_binfo
,
2463 virtual_depth
, virtualness
,
2464 parent_convs
, child_convs
,
2466 if (base_virtualness
)
2467 my_virtualness
= virtualness
= 1;
2468 child_convs
= chainon (base_convs
, child_convs
);
2471 *convs
= split_conversions (my_convs
, parent_convs
,
2472 child_convs
, other_convs
);
2474 return my_virtualness
;
2477 /* Return a TREE_LIST containing all the non-hidden user-defined
2478 conversion functions for TYPE (and its base-classes). The
2479 TREE_VALUE of each node is the FUNCTION_DECL of the conversion
2480 function. The TREE_PURPOSE is the BINFO from which the conversion
2481 functions in this node were selected. This function is effectively
2482 performing a set of member lookups as lookup_fnfield does, but
2483 using the type being converted to as the unique key, rather than the
2487 lookup_conversions (tree type
)
2491 complete_type (type
);
2492 if (!CLASS_TYPE_P (type
) || !TYPE_BINFO (type
))
2495 lookup_conversions_r (TYPE_BINFO (type
), 0, 0, NULL_TREE
, NULL_TREE
, &convs
);
2497 tree list
= NULL_TREE
;
2499 /* Flatten the list-of-lists */
2500 for (; convs
; convs
= TREE_CHAIN (convs
))
2504 for (probe
= TREE_VALUE (convs
); probe
; probe
= next
)
2506 next
= TREE_CHAIN (probe
);
2508 TREE_CHAIN (probe
) = list
;
2516 /* Returns the binfo of the first direct or indirect virtual base derived
2517 from BINFO, or NULL if binfo is not via virtual. */
2520 binfo_from_vbase (tree binfo
)
2522 for (; binfo
; binfo
= BINFO_INHERITANCE_CHAIN (binfo
))
2524 if (BINFO_VIRTUAL_P (binfo
))
2530 /* Returns the binfo of the first direct or indirect virtual base derived
2531 from BINFO up to the TREE_TYPE, LIMIT, or NULL if binfo is not
2535 binfo_via_virtual (tree binfo
, tree limit
)
2537 if (limit
&& !CLASSTYPE_VBASECLASSES (limit
))
2538 /* LIMIT has no virtual bases, so BINFO cannot be via one. */
2541 for (; binfo
&& !SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), limit
);
2542 binfo
= BINFO_INHERITANCE_CHAIN (binfo
))
2544 if (BINFO_VIRTUAL_P (binfo
))
2550 /* BINFO is for a base class in some hierarchy. Return true iff it is a
2554 binfo_direct_p (tree binfo
)
2556 tree d_binfo
= BINFO_INHERITANCE_CHAIN (binfo
);
2557 if (BINFO_INHERITANCE_CHAIN (d_binfo
))
2558 /* A second inheritance chain means indirect. */
2560 if (!BINFO_VIRTUAL_P (binfo
))
2561 /* Non-virtual, so only one inheritance chain means direct. */
2563 /* A virtual base looks like a direct base, so we need to look through the
2564 direct bases to see if it's there. */
2566 for (int i
= 0; BINFO_BASE_ITERATE (d_binfo
, i
, b_binfo
); ++i
)
2567 if (b_binfo
== binfo
)
2572 /* BINFO is a base binfo in the complete type BINFO_TYPE (HERE).
2573 Find the equivalent binfo within whatever graph HERE is located.
2574 This is the inverse of original_binfo. */
2577 copied_binfo (tree binfo
, tree here
)
2579 tree result
= NULL_TREE
;
2581 if (BINFO_VIRTUAL_P (binfo
))
2585 for (t
= here
; BINFO_INHERITANCE_CHAIN (t
);
2586 t
= BINFO_INHERITANCE_CHAIN (t
))
2589 result
= binfo_for_vbase (BINFO_TYPE (binfo
), BINFO_TYPE (t
));
2591 else if (BINFO_INHERITANCE_CHAIN (binfo
))
2597 cbinfo
= copied_binfo (BINFO_INHERITANCE_CHAIN (binfo
), here
);
2598 for (ix
= 0; BINFO_BASE_ITERATE (cbinfo
, ix
, base_binfo
); ix
++)
2599 if (SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo
), BINFO_TYPE (binfo
)))
2601 result
= base_binfo
;
2607 gcc_assert (SAME_BINFO_TYPE_P (BINFO_TYPE (here
), BINFO_TYPE (binfo
)));
2611 gcc_assert (result
);
2616 binfo_for_vbase (tree base
, tree t
)
2620 vec
<tree
, va_gc
> *vbases
;
2622 for (vbases
= CLASSTYPE_VBASECLASSES (t
), ix
= 0;
2623 vec_safe_iterate (vbases
, ix
, &binfo
); ix
++)
2624 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), base
))
2629 /* BINFO is some base binfo of HERE, within some other
2630 hierarchy. Return the equivalent binfo, but in the hierarchy
2631 dominated by HERE. This is the inverse of copied_binfo. If BINFO
2632 is not a base binfo of HERE, returns NULL_TREE. */
2635 original_binfo (tree binfo
, tree here
)
2639 if (SAME_BINFO_TYPE_P (BINFO_TYPE (binfo
), BINFO_TYPE (here
)))
2641 else if (BINFO_VIRTUAL_P (binfo
))
2642 result
= (CLASSTYPE_VBASECLASSES (BINFO_TYPE (here
))
2643 ? binfo_for_vbase (BINFO_TYPE (binfo
), BINFO_TYPE (here
))
2645 else if (BINFO_INHERITANCE_CHAIN (binfo
))
2649 base_binfos
= original_binfo (BINFO_INHERITANCE_CHAIN (binfo
), here
);
2655 for (ix
= 0; (base_binfo
= BINFO_BASE_BINFO (base_binfos
, ix
)); ix
++)
2656 if (SAME_BINFO_TYPE_P (BINFO_TYPE (base_binfo
),
2657 BINFO_TYPE (binfo
)))
2659 result
= base_binfo
;
2668 /* True iff TYPE has any dependent bases (and therefore we can't say
2669 definitively that another class is not a base of an instantiation of
2673 any_dependent_bases_p (tree type
)
2675 if (!type
|| !CLASS_TYPE_P (type
) || !uses_template_parms (type
))
2678 /* If we haven't set TYPE_BINFO yet, we don't know anything about the bases.
2679 Return false because in this situation we aren't actually looking up names
2680 in the scope of the class, so it doesn't matter whether it has dependent
2682 if (!TYPE_BINFO (type
))
2687 FOR_EACH_VEC_SAFE_ELT (BINFO_BASE_BINFOS (TYPE_BINFO (type
)), i
, base_binfo
)
2688 if (BINFO_DEPENDENT_BASE_P (base_binfo
))