Don't create a separate copy of virtual bases for the CLASSTYPE_VBASECLASSES list.

	Don't create a separate copy of virtual bases for the
	CLASSTYPE_VBASECLASSES list.
	* cp-tree.h (CLASSTYPE_VBASECLASSES): Change documentation.
	(BINFO_FOR_VBASE): Remove.
	(CANONICAL_BINFO): Adjust.
	(binfo_for_vbase): New function.
	* class.c (build_vbase_pointer_fields): Use binfo_for_vbase
	instead of BINFO_FOR_VBASE.
	(build_vbase_pointer): Likewise.
	(build_secondary_vtable): Likewise.
	(dfs_mark_primary_bases): Likewise.
	(mark_primary_bases): Likewise.
	(layout_nonempty_base_or_field): Likewise.
	(dfs_set_offset_for_shared_vbases): Likewise.
	(dfs_set_offset_for_unshared_vbases): Likewise.
	(layout_virtual_bases): Likewise.  Adjust for changes to the
	CLASSTYPE_VBASECLASSES list.
	(dump_class_hierarchy_r): Use binfo_for_vbase
	instead of BINFO_FOR_VBASE.
	(dump_class_hierarchy): Likewise.
	(finish_vtbls): Likewise.
	(build_vtbl_initializer): Adjust for changes to the
	CLASSTYPE_VBASECLASSES list.
	(build_vbase_offset_vtbl_entries): Use binfo_for_vbase.
	* decl.c (finish_destructor_body): Adjust for changes to the
	CLASSTYPE_VBASECLASSES list.
	* init.c (sort_base_init): Use binfo_for_vbase.
	(construct_virtual_bases): Adjust for changes to the
	CLASSTYPE_VBASECLASSES list.
	(expand_member_init): Use binfo_for_vbase.
	(build_vbase_delete):  Adjust for changes to the
	CLASSTYPE_VBASECLASSES list.
	* method.c (do_build_copy_constructor): Likewise.
	* rtti.c (get_base_offset): Use binfo_for_vbase.
	(expand_class_desc): Remove #if 0'd code.
	* search.c (struct vbase_info): Remove vbase_types.
	(get_base_distance):  Use binfo_for_vbase.
	(lookup_field_queue_p): Use CANONICAL_BINFO.
	(get_shared_vbase_if_not_primary): Use binfo_for_vbase.
	(get_pure_virtuals): Adjust for changes to the
	CLASSTYPE_VBASECLASSES list.
	(dfs_find_vbases): Use binfo_for_vbase.
	(dfs_init_vbase_pointers): Likewise.
	(init_vbase_pointers): Don't initialize vi.vbase_types.
	(virtual_context): Use binfo_for_vbase.
	(fixup_all_virtual_upcast_offsets): Adjust for changes to the
	CLASSTYPE_VBASECLASSES list.
	(expand_indirect_vtbls_init): Simplify.
	(dfs_get_vbase_types): Don't replicate virtual bases.
	(find_vbase_instance): Use binfo_for_vbase.
	(binfo_for_vbase): New function.
	* typeck.c (get_delta_difference): Use binfo_for_vbase.

From-SVN: r34040

9 files changed, 160 insertions, 170 deletions

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index bcde1a2..ebe1d69 100644
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,58 @@
+2000-05-19  Mark Mitchell  <mark@codesourcery.com>
+
+	Don't create a separate copy of virtual bases for the
+	CLASSTYPE_VBASECLASSES list.
+	* cp-tree.h (CLASSTYPE_VBASECLASSES): Change documentation.
+	(BINFO_FOR_VBASE): Remove.
+	(CANONICAL_BINFO): Adjust.
+	(binfo_for_vbase): New function.
+	* class.c (build_vbase_pointer_fields): Use binfo_for_vbase
+	instead of BINFO_FOR_VBASE.
+	(build_vbase_pointer): Likewise.
+	(build_secondary_vtable): Likewise.
+	(dfs_mark_primary_bases): Likewise.
+	(mark_primary_bases): Likewise.
+	(layout_nonempty_base_or_field): Likewise.
+	(dfs_set_offset_for_shared_vbases): Likewise.
+	(dfs_set_offset_for_unshared_vbases): Likewise.
+	(layout_virtual_bases): Likewise.  Adjust for changes to the
+	CLASSTYPE_VBASECLASSES list.
+	(dump_class_hierarchy_r): Use binfo_for_vbase
+	instead of BINFO_FOR_VBASE.
+	(dump_class_hierarchy): Likewise.
+	(finish_vtbls): Likewise.
+	(build_vtbl_initializer): Adjust for changes to the
+	CLASSTYPE_VBASECLASSES list.
+	(build_vbase_offset_vtbl_entries): Use binfo_for_vbase.
+	* decl.c (finish_destructor_body): Adjust for changes to the
+	CLASSTYPE_VBASECLASSES list.
+	* init.c (sort_base_init): Use binfo_for_vbase.
+	(construct_virtual_bases): Adjust for changes to the
+	CLASSTYPE_VBASECLASSES list.
+	(expand_member_init): Use binfo_for_vbase.
+	(build_vbase_delete):  Adjust for changes to the
+	CLASSTYPE_VBASECLASSES list.
+	* method.c (do_build_copy_constructor): Likewise.
+	* rtti.c (get_base_offset): Use binfo_for_vbase.
+	(expand_class_desc): Remove #if 0'd code.
+	* search.c (struct vbase_info): Remove vbase_types.
+	(get_base_distance):  Use binfo_for_vbase.
+	(lookup_field_queue_p): Use CANONICAL_BINFO.
+	(get_shared_vbase_if_not_primary): Use binfo_for_vbase.
+	(get_pure_virtuals): Adjust for changes to the
+	CLASSTYPE_VBASECLASSES list.
+	(dfs_find_vbases): Use binfo_for_vbase.
+	(dfs_init_vbase_pointers): Likewise.
+	(init_vbase_pointers): Don't initialize vi.vbase_types.
+	(virtual_context): Use binfo_for_vbase.
+	(fixup_all_virtual_upcast_offsets): Adjust for changes to the
+	CLASSTYPE_VBASECLASSES list.
+	(expand_indirect_vtbls_init): Simplify.
+	(dfs_get_vbase_types): Don't replicate virtual bases.
+	(find_vbase_instance): Use binfo_for_vbase.
+	(binfo_for_vbase): New function.
+	* typeck.c (get_delta_difference): Use binfo_for_vbase.
+	
 2000-05-17  Mark Mitchell  <mark@codesourcery.com>
 
 	* decl2.c (finish_anon_union): Generalize error messages to handle
diff --git a/gcc/cp/class.c b/gcc/cp/class.c
index 962ef12..cc63239 100644
--- a/gcc/cp/class.c
+++ b/gcc/cp/class.c
@@ -246,7 +246,7 @@ build_vbase_pointer_fields (rli, empty_p)
 	    {
 	      tree other_base_binfo = TREE_VEC_ELT (binfos, j);
 	      if (! TREE_VIA_VIRTUAL (other_base_binfo)
-		  && BINFO_FOR_VBASE (basetype, BINFO_TYPE (other_base_binfo)))
+		  && binfo_for_vbase (basetype, BINFO_TYPE (other_base_binfo)))
 		goto got_it;
 	    }
 	  FORMAT_VBASE_NAME (name, basetype);
@@ -285,7 +285,7 @@ build_vbase_pointer (exp, type)
 
       /* Find the shared copy of TYPE; that's where the vtable offset
 	 is recorded.  */
-      vbase = BINFO_FOR_VBASE (type, TREE_TYPE (exp));
+      vbase = binfo_for_vbase (type, TREE_TYPE (exp));
       /* Find the virtual function table pointer.  */
       vbase_ptr = build_vfield_ref (exp, TREE_TYPE (exp));
       /* Compute the location where the offset will lie.  */
@@ -841,7 +841,7 @@ build_secondary_vtable (binfo, for_type)
 #endif
 
   if (TREE_VIA_VIRTUAL (binfo))
-    my_friendly_assert (binfo == BINFO_FOR_VBASE (BINFO_TYPE (binfo),
+    my_friendly_assert (binfo == binfo_for_vbase (BINFO_TYPE (binfo),
 						  current_class_type),
 			170);
 
@@ -859,7 +859,7 @@ build_secondary_vtable (binfo, for_type)
 
   if (TREE_VIA_VIRTUAL (binfo))
     {
-      tree binfo1 = BINFO_FOR_VBASE (BINFO_TYPE (binfo), for_type);
+      tree binfo1 = binfo_for_vbase (BINFO_TYPE (binfo), for_type);
 
       /* XXX - This should never happen, if it does, the caller should
 	 ensure that the binfo is from for_type's binfos, not from any
@@ -1694,7 +1694,7 @@ dfs_mark_primary_bases (binfo, data)
       tree shared_binfo;
 
       shared_binfo 
-	= BINFO_FOR_VBASE (BINFO_TYPE (base_binfo), (tree) data);
+	= binfo_for_vbase (BINFO_TYPE (base_binfo), (tree) data);
 
       /* If this virtual base is not already primary somewhere else in
 	 the hiearchy, then we'll be using this copy.  */
@@ -1741,7 +1741,7 @@ mark_primary_bases (type)
       if (!TREE_VIA_VIRTUAL (vbases))
 	continue;
 
-      vbase = BINFO_FOR_VBASE (BINFO_TYPE (vbases), type);
+      vbase = binfo_for_vbase (BINFO_TYPE (vbases), type);
       if (BINFO_VBASE_PRIMARY_P (vbase))
 	/* This virtual base was already included in the hierarchy, so
 	   there's nothing to do here.  */
@@ -3667,7 +3667,7 @@ layout_nonempty_base_or_field (rli, decl, binfo, v)
 	 a data member.  */
       if (binfo && flag_new_abi && layout_conflict_p (binfo, v))
 	{
-	  /* Undo the propogate_binfo_offsets call.  */
+	  /* Undo the propagate_binfo_offsets call.  */
 	  offset = size_diffop (size_zero_node, offset);
 	  propagate_binfo_offsets (binfo, convert (ssizetype, offset));
 	 
@@ -4376,7 +4376,7 @@ dfs_set_offset_for_shared_vbases (binfo, data)
       /* Update the shared copy.  */
       tree shared_binfo;
 
-      shared_binfo = BINFO_FOR_VBASE (BINFO_TYPE (binfo), (tree) data);
+      shared_binfo = binfo_for_vbase (BINFO_TYPE (binfo), (tree) data);
       BINFO_OFFSET (shared_binfo) = BINFO_OFFSET (binfo);
     }
 
@@ -4399,7 +4399,7 @@ dfs_set_offset_for_unshared_vbases (binfo, data)
       tree vbase;
       tree offset;
       
-      vbase = BINFO_FOR_VBASE (BINFO_TYPE (binfo), t);
+      vbase = binfo_for_vbase (BINFO_TYPE (binfo), t);
       offset = size_diffop (BINFO_OFFSET (vbase), BINFO_OFFSET (binfo));
       propagate_binfo_offsets (binfo, offset);
     }
@@ -4448,13 +4448,14 @@ layout_virtual_bases (t, base_offsets)
     {
       tree vbase;
 
-      if (!TREE_VIA_VIRTUAL (vbases))
-	continue;
-
       if (flag_new_abi)
-	vbase = BINFO_FOR_VBASE (BINFO_TYPE (vbases), t);
+	{
+	  if (!TREE_VIA_VIRTUAL (vbases))
+	    continue;
+	  vbase = binfo_for_vbase (BINFO_TYPE (vbases), t);
+	}
       else
-	vbase = vbases;
+	vbase = TREE_VALUE (vbases);
 
       if (!BINFO_VBASE_PRIMARY_P (vbase))
 	{
@@ -4486,9 +4487,15 @@ layout_virtual_bases (t, base_offsets)
 			       *base_offsets);
 	  else
 	    {
+	      tree offset;
+
+	      offset = ssize_int (CEIL (dsize, BITS_PER_UNIT));
+	      offset = size_diffop (offset, 
+				    convert (ssizetype, 
+					     BINFO_OFFSET (vbase)));
+
 	      /* And compute the offset of the virtual base.  */
-	      propagate_binfo_offsets (vbase, 
-				       ssize_int (CEIL (dsize, BITS_PER_UNIT)));
+	      propagate_binfo_offsets (vbase, offset);
 	      /* Every virtual baseclass takes a least a UNIT, so that
 		 we can take it's address and get something different
 		 for each base.  */
@@ -4516,10 +4523,6 @@ layout_virtual_bases (t, base_offsets)
      in get_base_distance depend on the BINFO_OFFSETs being set
      correctly.  */
   dfs_walk (TYPE_BINFO (t), dfs_set_offset_for_unshared_vbases, NULL, t);
-  for (vbases = CLASSTYPE_VBASECLASSES (t);
-       vbases;
-       vbases = TREE_CHAIN (vbases))
-    dfs_walk (vbases, dfs_set_offset_for_unshared_vbases, NULL, t);
 
   /* If we had empty base classes that protruded beyond the end of the
      class, we didn't update DSIZE above; we were hoping to overlay
@@ -4542,7 +4545,7 @@ layout_virtual_bases (t, base_offsets)
 	 vbases; 
 	 vbases = TREE_CHAIN (vbases))
       {
-	tree basetype = BINFO_TYPE (vbases);
+	tree basetype = BINFO_TYPE (TREE_VALUE (vbases));
 	if (get_base_distance (basetype, t, 0, (tree*)0) == -2)
 	  cp_warning ("virtual base `%T' inaccessible in `%T' due to ambiguity",
 		      basetype, t);
@@ -6334,7 +6337,7 @@ dump_class_hierarchy_r (t, binfo, indent)
     fprintf (stderr, " virtual");
   if (BINFO_PRIMARY_MARKED_P (binfo)
       || (TREE_VIA_VIRTUAL (binfo) 
-	  && BINFO_VBASE_PRIMARY_P (BINFO_FOR_VBASE (BINFO_TYPE (binfo), 
+	  && BINFO_VBASE_PRIMARY_P (binfo_for_vbase (BINFO_TYPE (binfo), 
 						     t))))
     fprintf (stderr, " primary");
   fprintf (stderr, "\n");
@@ -6349,12 +6352,7 @@ void
 dump_class_hierarchy (t)
      tree t;
 {
-  tree vbase;
-
   dump_class_hierarchy_r (t, TYPE_BINFO (t), 0);
-  fprintf (stderr, "virtual bases\n");
-  for (vbase = CLASSTYPE_VBASECLASSES (t); vbase; vbase = TREE_CHAIN (vbase))
-    dump_class_hierarchy_r (t, vbase, 0);
 }
 
 /* Virtual function table initialization.  */
@@ -6383,7 +6381,7 @@ finish_vtbls (t)
 	{
 	  if (!TREE_VIA_VIRTUAL (vbase))
 	    continue;
-	  accumulate_vtbl_inits (BINFO_FOR_VBASE (BINFO_TYPE (vbase), t),
+	  accumulate_vtbl_inits (binfo_for_vbase (BINFO_TYPE (vbase), t),
 				 list);
 	}
 
@@ -6554,7 +6552,7 @@ build_vtbl_initializer (binfo, original_binfo, t, rtti_binfo,
   for (vbase = CLASSTYPE_VBASECLASSES (t); 
        vbase; 
        vbase = TREE_CHAIN (vbase))
-    CLEAR_BINFO_VTABLE_PATH_MARKED (vbase);
+    CLEAR_BINFO_VTABLE_PATH_MARKED (TREE_VALUE (vbase));
 
   /* Add entries to the vtable for RTTI.  */
   inits = chainon (inits, build_rtti_vtbl_entries (binfo, rtti_binfo));
@@ -6673,7 +6671,7 @@ build_vbase_offset_vtbl_entries (binfo, vod)
 
       /* Find the instance of this virtual base in the complete
 	 object.  */
-      b = BINFO_FOR_VBASE (BINFO_TYPE (vbase), t);
+      b = binfo_for_vbase (BINFO_TYPE (vbase), t);
 
       /* If we've already got an offset for this virtual base, we
 	 don't need another one.  */
@@ -6694,7 +6692,7 @@ build_vbase_offset_vtbl_entries (binfo, vod)
 	  tree orig_vbase;
 
 	  /* Find the instance of this virtual base in the type of BINFO.  */
-	  orig_vbase = BINFO_FOR_VBASE (BINFO_TYPE (vbase),
+	  orig_vbase = binfo_for_vbase (BINFO_TYPE (vbase),
 					BINFO_TYPE (binfo));
 
 	  /* The vbase offset had better be the same.  */
diff --git a/gcc/cp/cp-tree.h b/gcc/cp/cp-tree.h
index fc5cf2c..aa9fdaf 100644
--- a/gcc/cp/cp-tree.h
+++ b/gcc/cp/cp-tree.h
@@ -1598,34 +1598,15 @@ struct lang_type
 /* A chain of BINFOs for the direct and indirect virtual base classes
    that this type uses in a post-order depth-first left-to-right
    order.  (In other words, these bases appear in the order that they
-   should be initialized.)
-
-   These BINFOs are distinct from those in the TYPE_BINFO hierarchy.
-   So, given:
-
-     struct A {};
-     struct B : public A {};
-     struct C : virtual public B {};
-     struct D : virtual public B {};
-     struct E : public C, public D {};
-
-   there will be two copies of `A' and `B' in the TYPE_BINFO hierarchy
-   for `E'.  On the CLASSTYPE_VBASECLASSES list, there will be just
-   one copy of `B' (distinct from the other two) with its own copy of `A'
-   (also distinct from the copies in the TYPE_BINFO hierarchy.)  */
+   should be initialized.)  */
 #define CLASSTYPE_VBASECLASSES(NODE) (TYPE_LANG_SPECIFIC(NODE)->vbases)
 
-/* The BINFO (if any) for the virtual baseclass T of the class C from
-   the CLASSTYPE_VBASECLASSES list.  */
-#define BINFO_FOR_VBASE(T, C) \
-  (binfo_member (T, CLASSTYPE_VBASECLASSES (C)))
-
 /* For a non-virtual BINFO, the BINFO itself; for a virtual BINFO, the
-   BINFO_FOR_VBASE.  C is the most derived class for the hierarchy
+   binfo_for_vbase.  C is the most derived class for the hierarchy
    containing BINFO.  */
 #define CANONICAL_BINFO(BINFO, C)		\
   (TREE_VIA_VIRTUAL (BINFO) 			\
-   ? BINFO_FOR_VBASE (BINFO_TYPE (BINFO), C) 	\
+   ? binfo_for_vbase (BINFO_TYPE (BINFO), C) 	\
    : BINFO)
 
 /* Number of direct baseclasses of NODE.  */
@@ -1718,9 +1699,7 @@ struct lang_type
    for B (in D) will have a BINFO_INHERITANCE_CHAIN pointing to
    D.  In tree.h, this pointer is described as pointing in other
    direction.  There is a different BINFO for each path to a virtual
-   base; BINFOs for virtual bases are not shared.  In addition, shared
-   versions of each of the virtual class BINFOs are stored in
-   CLASSTYPE_VBASECLASSES.
+   base; BINFOs for virtual bases are not shared.
 
    We use TREE_VIA_PROTECTED and TREE_VIA_PUBLIC, but private
    inheritance is indicated by the absence of the other two flags, not
@@ -1760,29 +1739,13 @@ struct lang_type
 /* Nonzero if this BINFO is a primary base class.
 
    In the TYPE_BINFO hierarchy, this flag is never set for a base
-   class of a non-primary virtual base because the copies of a
-   non-primary virtual base that appear in the TYPE_BINFO hierarchy do
-   not really exist.  Instead, it is the BINFOs in the
-   CLASSTYPE_VBASECLASSES list that are used.  In other words, this
-   flag is only valid for paths (given by BINFO_INHERITANCE_CHAIN)
-   that really exist in the final object.  
-
-   For example, consider:
-
-      struct A {};
-      struct B : public A { };
-      struct C : virtual public B { void f(); int i; };
-
-   `A' is the primary base class for `B'.  But, `B' is not a primary
-   base class for `C'.  So, in the copy of `A' that appears in the
-   TYPE_BINFO hierarcy for `C' does not have BINFO_PRIMARY_MARKED_P
-   set; the copy in the CLASSTYPE_VBASECLASSES list does have this
-   set.  */
+   class of a non-primary virtual base.  This flag is only valid for
+   paths (given by BINFO_INHERITANCE_CHAIN) that really exist in the
+   final object.  */
 #define BINFO_PRIMARY_MARKED_P(NODE) TREE_LANG_FLAG_5 (NODE)
 
 /* Nonzero if the virtual baseclass with the type given by this BINFO
-   is primary *somewhere* in the hierarchy.  This flag is only set on 
-   entries in the CLASSTYPE_VBASECLASSES list.  */
+   is primary *somewhere* in the hierarchy.  */
 #define BINFO_VBASE_PRIMARY_P(NODE) TREE_LANG_FLAG_6 (NODE)
 
 /* Used by various search routines.  */
@@ -4365,6 +4328,7 @@ extern tree marked_vtable_pathp                 PARAMS ((tree, void *));
 extern tree unmarked_vtable_pathp               PARAMS ((tree, void *));
 extern tree convert_pointer_to_vbase            PARAMS ((tree, tree));
 extern tree find_vbase_instance                 PARAMS ((tree, tree));
+extern tree binfo_for_vbase                     PARAMS ((tree, tree));
 
 /* in semantics.c */
 extern void finish_expr_stmt                    PARAMS ((tree));
diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c
index 6f09a7a..52e67ae 100644
--- a/gcc/cp/decl.c
+++ b/gcc/cp/decl.c
@@ -13863,26 +13863,34 @@ finish_destructor_body ()
       /* Run destructors for all virtual baseclasses.  */
       if (TYPE_USES_VIRTUAL_BASECLASSES (current_class_type))
 	{
-	  tree vbases = nreverse (copy_list (CLASSTYPE_VBASECLASSES (current_class_type)));
-	  tree if_stmt = begin_if_stmt ();
+	  tree vbases;
+	  tree if_stmt;
+
+	  if_stmt = begin_if_stmt ();
 	  finish_if_stmt_cond (build (BIT_AND_EXPR, integer_type_node,
 				      current_in_charge_parm,
 				      integer_two_node),
 			       if_stmt);
 
-	  while (vbases)
+	  vbases = CLASSTYPE_VBASECLASSES (current_class_type);
+	  /* The CLASSTYPE_VBASECLASSES list is in initialization
+	     order, so we have to march through it in reverse order.  */
+	  for (vbases = nreverse (copy_list (vbases));
+	       vbases;
+	       vbases = TREE_CHAIN (vbases))
 	    {
-	      if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (BINFO_TYPE (vbases)))
+	      tree vbase = TREE_VALUE (vbases);
+
+	      if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (BINFO_TYPE (vbase)))
 		{
 		  tree vb = get_vbase
-		    (BINFO_TYPE (vbases),
+		    (BINFO_TYPE (vbase),
 		     TYPE_BINFO (current_class_type));
 		  finish_expr_stmt
 		    (build_scoped_method_call
 		     (current_class_ref, vb, base_dtor_identifier,
 		      NULL_TREE));
 		}
-	      vbases = TREE_CHAIN (vbases);
 	    }
 
 	  finish_then_clause (if_stmt);
diff --git a/gcc/cp/init.c b/gcc/cp/init.c
index 81c301a..d31728d 100644
--- a/gcc/cp/init.c
+++ b/gcc/cp/init.c
@@ -537,7 +537,7 @@ sort_base_init (t, rbase_ptr, vbase_ptr)
 	     this constructor is the top-level constructor called.  */
 	  if (TREE_VIA_VIRTUAL (binfo))
 	    {
-	      tree v = BINFO_FOR_VBASE (BINFO_TYPE (binfo), t);
+	      tree v = binfo_for_vbase (BINFO_TYPE (binfo), t);
 	      vbases = tree_cons (v, TREE_VALUE (x), vbases);
 	      continue;
 	    }
@@ -855,6 +855,7 @@ construct_virtual_bases (type, this_ref, this_ptr, init_list, flag)
       tree inner_if_stmt;
       tree compound_stmt;
       tree exp;
+      tree vbase;
 
       /* If there are virtual base classes with destructors, we need to
 	 emit cleanups to destroy them if an exception is thrown during
@@ -878,21 +879,22 @@ construct_virtual_bases (type, this_ref, this_ptr, init_list, flag)
 	 constructing virtual bases, then we must be the most derived
 	 class.  Therefore, we don't have to look up the virtual base;
 	 we already know where it is.  */
+      vbase = TREE_VALUE (vbases);
       exp = build (PLUS_EXPR,
 		   TREE_TYPE (this_ptr),
 		   this_ptr,
 		   fold (build1 (NOP_EXPR, TREE_TYPE (this_ptr),
-				 BINFO_OFFSET (vbases))));
+				 BINFO_OFFSET (vbase))));
       exp = build1 (NOP_EXPR, 
-		    build_pointer_type (BINFO_TYPE (vbases)), 
+		    build_pointer_type (BINFO_TYPE (vbase)), 
 		    exp);
 
-      expand_aggr_vbase_init_1 (vbases, this_ref, exp, init_list);
+      expand_aggr_vbase_init_1 (vbase, this_ref, exp, init_list);
       finish_compound_stmt (/*has_no_scope=*/1, compound_stmt);
       finish_then_clause (inner_if_stmt);
       finish_if_stmt ();
       
-      expand_cleanup_for_base (vbases, flag);
+      expand_cleanup_for_base (vbase, flag);
     }
 }
 
@@ -1022,7 +1024,7 @@ expand_member_init (exp, name, init)
 	       && ! current_template_parms
 	       && ! vec_binfo_member (basetype,
 				      TYPE_BINFO_BASETYPES (type))
-	       && ! BINFO_FOR_VBASE (basetype, type))
+	       && ! binfo_for_vbase (basetype, type))
 	{
 	  if (IDENTIFIER_CLASS_VALUE (name))
 	    goto try_member;
@@ -3290,8 +3292,9 @@ build_vbase_delete (type, decl)
 
   while (vbases)
     {
-      tree this_addr = convert_force (build_pointer_type (BINFO_TYPE (vbases)),
-				      addr, 0);
+      tree this_addr 
+	= convert_force (build_pointer_type (BINFO_TYPE (TREE_VALUE (vbases))),
+			 addr, 0);
       result = tree_cons (NULL_TREE,
 			  build_delete (TREE_TYPE (this_addr), this_addr,
 					integer_zero_node,
diff --git a/gcc/cp/method.c b/gcc/cp/method.c
index 6491e2b..81df59a 100644
--- a/gcc/cp/method.c
+++ b/gcc/cp/method.c
@@ -2262,7 +2262,8 @@ do_build_copy_constructor (fndecl)
       for (t = CLASSTYPE_VBASECLASSES (current_class_type); t;
 	   t = TREE_CHAIN (t))
 	current_base_init_list 
-	  = tree_cons (BINFO_TYPE (t), parm, current_base_init_list);
+	  = tree_cons (BINFO_TYPE (TREE_VALUE (t)), parm, 
+		       current_base_init_list);
       for (i = 0; i < n_bases; ++i)
 	{
 	  t = TREE_VEC_ELT (binfos, i);
diff --git a/gcc/cp/rtti.c b/gcc/cp/rtti.c
index 426c5c3..a7c13b5 100644
--- a/gcc/cp/rtti.c
+++ b/gcc/cp/rtti.c
@@ -548,7 +548,7 @@ get_base_offset (binfo, parent)
     /* Under the new ABI, we store the vtable offset at which
        the virtual base offset can be found.  */
     return convert (sizetype,
-		    BINFO_VPTR_FIELD (BINFO_FOR_VBASE (BINFO_TYPE (binfo),
+		    BINFO_VPTR_FIELD (binfo_for_vbase (BINFO_TYPE (binfo),
 						       parent)));
 
 }
@@ -930,11 +930,6 @@ expand_class_desc (tdecl, type)
   int i = CLASSTYPE_N_BASECLASSES (type);
   int base_cnt = 0;
   tree binfos = TYPE_BINFO_BASETYPES (type);
-#if 0
-  /* See code below that used these.  */
-  tree vb = CLASSTYPE_VBASECLASSES (type);
-  int n_base = i;
-#endif
   tree base, elems, access, offset, isvir;
   tree elt, elts = NULL_TREE;
 
@@ -1000,39 +995,6 @@ expand_class_desc (tdecl, type)
       elts = tree_cons (NULL_TREE, elt, elts);
       base_cnt++;
     }
-#if 0
-  i = n_base;
-  while (vb)
-    {
-      tree b;
-      access = access_public_node;
-      while (--i >= 0)
-	{
-	  b = TREE_VEC_ELT (binfos, i);
-	  if (BINFO_TYPE (vb) == BINFO_TYPE (b) && TREE_VIA_VIRTUAL (b))
-	    {
-	      if (TREE_VIA_PUBLIC (b))
-		access = access_public_node;
-	      else if (TREE_VIA_PROTECTED (b))
-		access = access_protected_node;
-	      else
-		access = access_private_node;
-	      break;
-	    }
-	}
-      base = build_t_desc (BINFO_TYPE (vb), 1);
-      offset = BINFO_OFFSET (vb);
-      isvir = build_int_2 (1, 0);
-
-      base_list = tree_cons (NULL_TREE, base, base_list);
-      isvir_list = tree_cons (NULL_TREE, isvir, isvir_list);
-      acc_list = tree_cons (NULL_TREE, access, acc_list);
-      off_list = tree_cons (NULL_TREE, offset, off_list);
-
-      base_cnt++;
-      vb = TREE_CHAIN (vb);
-    }
-#endif
 
   name_string = tinfo_name (type);
 
diff --git a/gcc/cp/search.c b/gcc/cp/search.c
index b296ea5..7dd03d4 100644
--- a/gcc/cp/search.c
+++ b/gcc/cp/search.c
@@ -82,7 +82,6 @@ struct vbase_info
   tree type;
   tree decl_ptr;
   tree inits;
-  tree vbase_types;
 };
 
 static tree next_baselink PARAMS ((tree));
@@ -491,9 +490,8 @@ get_base_distance (parent, binfo, protect, path_ptr)
      tree, deal with it.  This happens when we are called from
      expand_upcast_fixups.  */
   if (rval == -1 && TREE_CODE (parent) == TREE_VEC
-      && parent == BINFO_FOR_VBASE (BINFO_TYPE (parent), type))
+      && parent == binfo_for_vbase (BINFO_TYPE (parent), type))
     {
-      my_friendly_assert (BINFO_INHERITANCE_CHAIN (parent) == binfo, 980827);
       new_binfo = parent;
       rval = 1;
     }
@@ -1351,10 +1349,7 @@ lookup_field_queue_p (binfo, data)
       && hides (lfi->rval_binfo, binfo))
     return NULL_TREE;
 
-  if (TREE_VIA_VIRTUAL (binfo))
-    return BINFO_FOR_VBASE (BINFO_TYPE (binfo), lfi->type);
-  else
-    return binfo;
+  return CANONICAL_BINFO (binfo, lfi->type);
 }
 
 /* Within the scope of a template class, you can refer to the to the
@@ -2230,7 +2225,7 @@ get_shared_vbase_if_not_primary (binfo, data)
 
       /* This is a non-primary virtual base.  If there is no primary
 	 version, get the shared version.  */
-      binfo = BINFO_FOR_VBASE (BINFO_TYPE (binfo), type);
+      binfo = binfo_for_vbase (BINFO_TYPE (binfo), type);
       if (BINFO_VBASE_PRIMARY_P (binfo))
 	return NULL_TREE;
     }
@@ -2344,7 +2339,7 @@ get_pure_virtuals (type)
     {
       tree virtuals;
 
-      for (virtuals = BINFO_VIRTUALS (vbases);
+      for (virtuals = BINFO_VIRTUALS (TREE_VALUE (vbases));
 	   virtuals;
 	   virtuals = TREE_CHAIN (virtuals))
 	{
@@ -2492,7 +2487,7 @@ dfs_find_vbases (binfo, data)
 	  && CLASSTYPE_SEARCH_SLOT (BINFO_TYPE (base_binfo)) == 0)
 	{
 	  tree vbase = BINFO_TYPE (base_binfo);
-	  tree binfo = binfo_member (vbase, vi->vbase_types);
+	  tree binfo = binfo_for_vbase (vbase, vi->type);
 	  tree ptr_type = build_pointer_type (vbase);
 
 	  CLASSTYPE_SEARCH_SLOT (vbase)
@@ -2546,10 +2541,11 @@ dfs_init_vbase_pointers (binfo, data)
       tree ref = build (COMPONENT_REF, TREE_TYPE (fields),
 			build_indirect_ref (this_vbase_ptr, NULL_PTR), fields);
       tree init = CLASSTYPE_SEARCH_SLOT (TREE_TYPE (TREE_TYPE (fields)));
-      vi->inits = tree_cons (binfo_member (TREE_TYPE (TREE_TYPE (fields)),
-					   vi->vbase_types),
-			     build_modify_expr (ref, NOP_EXPR, init),
-			     vi->inits);
+      vi->inits 
+	= tree_cons (binfo_for_vbase (TREE_TYPE (TREE_TYPE (fields)),
+				      vi->type),
+		     build_modify_expr (ref, NOP_EXPR, init),
+		     vi->inits);
       fields = TREE_CHAIN (fields);
     }
   
@@ -2590,7 +2586,6 @@ init_vbase_pointers (type, decl_ptr)
 	 initialization.  */
       vi.type = type;
       vi.decl_ptr = decl_ptr;
-      vi.vbase_types = CLASSTYPE_VBASECLASSES (type);
       vi.inits = NULL_TREE;
 
       dfs_walk (binfo, dfs_find_vbases, unmarked_vtable_pathp, &vi);
@@ -2635,7 +2630,7 @@ virtual_context (fndecl, t, vbase)
 	      /* Not sure if checking path == vbase is necessary here, but just in
 		 case it is.  */
 	      if (TREE_VIA_VIRTUAL (path) || path == vbase)
-		return BINFO_FOR_VBASE (BINFO_TYPE (path), t);
+		return binfo_for_vbase (BINFO_TYPE (path), t);
 	      path = BINFO_INHERITANCE_CHAIN (path);
 	    }
 	}
@@ -2646,7 +2641,7 @@ virtual_context (fndecl, t, vbase)
   while (path)
     {
       if (TREE_VIA_VIRTUAL (path))
-	return BINFO_FOR_VBASE (BINFO_TYPE (path), t);
+	return binfo_for_vbase (BINFO_TYPE (path), t);
       path = BINFO_INHERITANCE_CHAIN (path);
     }
   return 0;
@@ -2873,11 +2868,11 @@ fixup_all_virtual_upcast_offsets (type, decl_ptr)
 	  tree vbase_offsets;
 	  tree addr;
 
-	  vbase = find_vbase_instance (BINFO_TYPE (vbases), type);
+	  vbase = find_vbase_instance (TREE_PURPOSE (vbases), type);
 	  vbase_offsets = NULL_TREE;
-	  addr = convert_pointer_to_vbase (BINFO_TYPE (vbases), decl_ptr);
+	  addr = convert_pointer_to_vbase (TREE_PURPOSE (vbases), decl_ptr);
 	  fixup_virtual_upcast_offsets (vbase,
-					TYPE_BINFO (BINFO_TYPE (vbases)),
+					TYPE_BINFO (TREE_PURPOSE (vbases)),
 					1, 0, addr, decl_ptr,
 					type, vbase, &vbase_offsets);
 	}
@@ -2916,11 +2911,9 @@ expand_indirect_vtbls_init (binfo, decl_ptr)
 
   if (TYPE_USES_VIRTUAL_BASECLASSES (type))
     {
-      tree vbases = CLASSTYPE_VBASECLASSES (type);
       struct vbase_info vi;
       vi.type = type;
       vi.decl_ptr = decl_ptr;
-      vi.vbase_types = vbases;
 
       dfs_walk (binfo, dfs_find_vbases, NULL, &vi);
       fixup_all_virtual_upcast_offsets (type, vi.decl_ptr);
@@ -2940,17 +2933,10 @@ dfs_get_vbase_types (binfo, data)
   tree type = (tree) data;
 
   if (TREE_VIA_VIRTUAL (binfo))
-    {
-      tree new_vbase = make_binfo (size_zero_node, 
-				   BINFO_TYPE (binfo),
-				   BINFO_VTABLE (binfo),
-				   BINFO_VIRTUALS (binfo));
-      unshare_base_binfos (new_vbase);
-      TREE_VIA_VIRTUAL (new_vbase) = 1;
-      BINFO_INHERITANCE_CHAIN (new_vbase) = TYPE_BINFO (type);
-      TREE_CHAIN (new_vbase) = CLASSTYPE_VBASECLASSES (type);
-      CLASSTYPE_VBASECLASSES (type) = new_vbase;
-    }
+    CLASSTYPE_VBASECLASSES (type)
+      = tree_cons (BINFO_TYPE (binfo), 
+		   binfo, 
+		   CLASSTYPE_VBASECLASSES (type));
   SET_BINFO_MARKED (binfo);
   return NULL_TREE;
 }
@@ -3022,7 +3008,7 @@ find_vbase_instance (base, type)
 {
   tree instance;
 
-  instance = BINFO_FOR_VBASE (base, type);
+  instance = binfo_for_vbase (base, type);
   if (!BINFO_VBASE_PRIMARY_P (instance))
     return instance;
 
@@ -3527,3 +3513,17 @@ binfo_from_vbase (binfo)
     }
   return 0;
 }
+
+/* Returns the BINFO (if any) for the virtual baseclass T of the class
+   C from the CLASSTYPE_VBASECLASSES list.  */
+
+tree
+binfo_for_vbase (basetype, classtype)
+     tree basetype;
+     tree classtype;
+{
+  tree binfo;
+
+  binfo = purpose_member (basetype, CLASSTYPE_VBASECLASSES (classtype));
+  return binfo ? TREE_VALUE (binfo) : NULL_TREE;
+}
diff --git a/gcc/cp/typeck.c b/gcc/cp/typeck.c
index 01606fa..378fc6b 100644
--- a/gcc/cp/typeck.c
+++ b/gcc/cp/typeck.c
@@ -5986,11 +5986,10 @@ get_delta_difference (from, to, force)
   if (to == from)
     return delta;
 
-  /* Should get_base_distance here, so we can check if any thing along the
-     path is virtual, and we need to make sure we stay
-     inside the real binfos when going through virtual bases.
-     Maybe we should replace virtual bases with
-     binfo_member (...CLASSTYPE_VBASECLASSES...)...  (mrs) */
+  /* Should get_base_distance here, so we can check if any thing along
+     the path is virtual, and we need to make sure we stay inside the
+     real binfos when going through virtual bases.  Maybe we should
+     replace virtual bases with BINFO_FOR_VBASE ... (mrs) */
   binfo = get_binfo (from, to, 1);
   if (binfo == error_mark_node)
     {
@@ -6010,7 +6009,7 @@ get_delta_difference (from, to, force)
 	return delta;
       if (binfo_from_vbase (binfo))
 	{
-	  binfo = BINFO_FOR_VBASE (BINFO_TYPE (binfo), from);
+	  binfo = binfo_for_vbase (BINFO_TYPE (binfo), from);
 	  cp_warning ("pointer to member cast to virtual base `%T' will only work if you are very careful", BINFO_TYPE (binfo));
 	}
       delta = BINFO_OFFSET (binfo);