Use vector API for vbase list.

	* cp-tree.h: Include vec.h
	(DEF_VEC_P (tree)): New type.
	(struct lang_type_class): Change vbase's member type.
	(binfo_for_vbase): Declare.
	* class.c (determine_primary_base, base_derived_from,
	update_vtable_entry_for_fn, walk_subobject_offsets, end_of_class,
	warn_about_ambiguous_bases, dfs_accumulate_vtbl_inits,
	build_vtbl_initializer): Adjust.
	* decl.c (xref_basetypes): Adjust, accumulate upper bound of
	vbases.
	* init.c (sort_mem_initializers, expand_member_init,
	push_base_cleanups): Adjust.
	* method.c (do_build_copy_constructor): Adjust.
	* search.c (get_pure_virtuals, copied_binfo, original_binfo): Adjust.
	(binfo_for_vbase): New.
	* tree.c (copy_base_binfos): Adjust.

From-SVN: r83770

gcc/cp/ChangeLog

+2004-06-28  Nathan Sidwell  <nathan@codesourcery.com>
+
+	Use vector API for vbase list.
+	* cp-tree.h: Include vec.h
+	(DEF_VEC_P (tree)): New type.
+	(struct lang_type_class): Change vbase's member type.
+	(binfo_for_vbase): Declare.
+	* class.c (determine_primary_base, base_derived_from,
+	update_vtable_entry_for_fn, walk_subobject_offsets, end_of_class,
+	warn_about_ambiguous_bases, dfs_accumulate_vtbl_inits,
+	build_vtbl_initializer): Adjust.
+	* decl.c (xref_basetypes): Adjust, accumulate upper bound of
+	vbases.
+	* init.c (sort_mem_initializers, expand_member_init,
+	push_base_cleanups): Adjust.
+	* method.c (do_build_copy_constructor): Adjust.
+	* search.c (get_pure_virtuals, copied_binfo, original_binfo): Adjust.
+	(binfo_for_vbase): New.
+	* tree.c (copy_base_binfos): Adjust.
+
 2004-06-28  Mark Mitchell  <mark@codesourcery.com>
 
 	* parser.c (cp_parser_set_decl_spec_type): Fix thinko.

gcc/cp/class.c

@@ -1344,9 +1344,9 @@ set_primary_base (tree t, tree binfo)
 static void
 determine_primary_base (tree t)
 {
-  int i, n_baseclasses = CLASSTYPE_N_BASECLASSES (t);
-  tree vbases;
+  unsigned i, n_baseclasses = CLASSTYPE_N_BASECLASSES (t);
   tree type_binfo;
+  tree vbase_binfo;
 
   /* If there are no baseclasses, there is certainly no primary base.  */
   if (n_baseclasses == 0)
@@ -1394,29 +1394,26 @@ determine_primary_base (tree t)
 
   /* Find the indirect primary bases - those virtual bases which are primary
      bases of something else in this hierarchy.  */
-  for (vbases = CLASSTYPE_VBASECLASSES (t);
-       vbases;
-       vbases = TREE_CHAIN (vbases)) 
+  for (i = 0; (vbase_binfo = VEC_iterate
+	       (tree, CLASSTYPE_VBASECLASSES (t), i)); i++)
     {
-      tree vbase_binfo = TREE_VALUE (vbases);
+      unsigned j;
 
-      /* See if this virtual base is an indirect primary base.  To be so,
-         it must be a primary base within the hierarchy of one of our
-         direct bases.  */
-      for (i = 0; i < n_baseclasses; ++i) 
+      /* See if this virtual base is an indirect primary base.  To be
+         so, it must be a primary base within the hierarchy of one of
+         our direct bases.  */
+      for (j = 0; j != n_baseclasses; ++j) 
 	{
-	  tree basetype = TYPE_BINFO_BASETYPE (t, i);
-	  tree v;
-
-	  for (v = CLASSTYPE_VBASECLASSES (basetype); 
-	       v; 
-	       v = TREE_CHAIN (v))
+	  unsigned k;
+	  tree base_vbase_binfo;
+	  tree basetype = TYPE_BINFO_BASETYPE (t, j);
+	  
+	  for (k = 0; (base_vbase_binfo = VEC_iterate
+		       (tree, CLASSTYPE_VBASECLASSES (basetype), k)); k++)
 	    {
-	      tree base_vbase = TREE_VALUE (v);
-	      
-	      if (BINFO_PRIMARY_P (base_vbase)
-		  && same_type_p (BINFO_TYPE (base_vbase),
-	                          BINFO_TYPE (vbase_binfo)))
+	      if (BINFO_PRIMARY_P (base_vbase_binfo)
+		  && same_type_p (BINFO_TYPE (base_vbase_binfo),
+				  BINFO_TYPE (vbase_binfo)))
 		{
 		  BINFO_INDIRECT_PRIMARY_P (vbase_binfo) = 1;
 		  break;
@@ -1923,9 +1920,8 @@ base_derived_from (tree derived, tree base)
 	/* If we meet a virtual base, we can't follow the inheritance
 	   any more.  See if the complete type of DERIVED contains
 	   such a virtual base.  */
-	return purpose_member (BINFO_TYPE (probe),
-			       CLASSTYPE_VBASECLASSES (BINFO_TYPE (derived)))
-	  != NULL_TREE;
+	return (binfo_for_vbase (BINFO_TYPE (probe), BINFO_TYPE (derived))
+		!= NULL_TREE);
     }
   return false;
 }
@@ -2169,10 +2165,8 @@ update_vtable_entry_for_fn (tree t, tree binfo, tree fn, tree* virtuals,
 	/* Find the equivalent binfo within the return type of the
 	   overriding function. We will want the vbase offset from
 	   there.  */
-	virtual_offset =
-	  TREE_VALUE (purpose_member
-		      (BINFO_TYPE (virtual_offset),
-		       CLASSTYPE_VBASECLASSES (TREE_TYPE (over_return))));
+	virtual_offset = binfo_for_vbase (BINFO_TYPE (virtual_offset),
+					  TREE_TYPE (over_return));
       else if (!same_type_p (TREE_TYPE (over_return),
 			     TREE_TYPE (base_return)))
 	{
@@ -3314,9 +3308,9 @@ walk_subobject_offsets (tree type,
 	    return r;
 	}
 
-      if (abi_version_at_least (2))
+      if (abi_version_at_least (2) && CLASSTYPE_VBASECLASSES (type))
 	{
-	  tree vbase;
+	  unsigned ix;
 
 	  /* Iterate through the virtual base classes of TYPE.  In G++
 	     3.2, we included virtual bases in the direct base class
@@ -3324,11 +3318,9 @@ walk_subobject_offsets (tree type,
 	     correct offsets for virtual bases are only known when
 	     working with the most derived type.  */
 	  if (vbases_p)
-	    for (vbase = CLASSTYPE_VBASECLASSES (type);
-		 vbase;
-		 vbase = TREE_CHAIN (vbase))
+	    for (ix = 0; (binfo = VEC_iterate
+			  (tree, CLASSTYPE_VBASECLASSES (type), ix)); ix++)
 	      {
-		binfo = TREE_VALUE (vbase);
 		r = walk_subobject_offsets (binfo,
 					    f,
 					    size_binop (PLUS_EXPR,
@@ -3345,7 +3337,8 @@ walk_subobject_offsets (tree type,
 	      /* We still have to walk the primary base, if it is
 		 virtual.  (If it is non-virtual, then it was walked
 		 above.)  */
-	      vbase = get_primary_binfo (type_binfo);
+	      tree vbase = get_primary_binfo (type_binfo);
+	      
 	      if (vbase && TREE_VIA_VIRTUAL (vbase)
 		  && BINFO_PRIMARY_BASE_OF (vbase) == type_binfo)
 		{
@@ -4525,11 +4518,10 @@ end_of_class (tree t, int include_virtuals_p)
 
   /* G++ 3.2 did not check indirect virtual bases.  */
   if (abi_version_at_least (2) && include_virtuals_p)
-    for (binfo = CLASSTYPE_VBASECLASSES (t); 
-	 binfo; 
-	 binfo = TREE_CHAIN (binfo))
+    for (i = 0; (binfo = VEC_iterate
+		 (tree, CLASSTYPE_VBASECLASSES (t), i)); i++)
       {
-	offset = end_of_base (TREE_VALUE (binfo));
+	offset = end_of_base (binfo);
 	if (INT_CST_LT_UNSIGNED (result, offset))
 	  result = offset;
       }
@@ -4551,8 +4543,8 @@ static void
 warn_about_ambiguous_bases (tree t)
 {
   int i;
-  tree vbases;
   tree basetype;
+  tree binfo;
 
   /* Check direct bases.  */
   for (i = 0; i < CLASSTYPE_N_BASECLASSES (t); ++i)
@@ -4566,11 +4558,10 @@ warn_about_ambiguous_bases (tree t)
 
   /* Check for ambiguous virtual bases.  */
   if (extra_warnings)
-    for (vbases = CLASSTYPE_VBASECLASSES (t); 
-	 vbases; 
-	 vbases = TREE_CHAIN (vbases))
+    for (i = 0; (binfo = VEC_iterate
+		 (tree, CLASSTYPE_VBASECLASSES (t), i)); i++)
       {
-	basetype = BINFO_TYPE (TREE_VALUE (vbases));
+	basetype = BINFO_TYPE (binfo);
 	
 	if (!lookup_base (t, basetype, ba_ignore | ba_quiet, NULL))
 	  warning ("virtual base `%T' inaccessible in `%T' due to ambiguity",
@@ -7272,8 +7263,7 @@ dfs_accumulate_vtbl_inits (tree binfo,
 	 either case, we share our vtable with LAST, i.e. the
 	 derived-most base within B of which we are a primary.  */
       if (b == rtti_binfo
-	  || (b && purpose_member (BINFO_TYPE (b),
-				   CLASSTYPE_VBASECLASSES (BINFO_TYPE (rtti_binfo)))))
+	  || (b && binfo_for_vbase (BINFO_TYPE (b), BINFO_TYPE (rtti_binfo))))
 	/* Just set our BINFO_VTABLE to point to LAST, as we may not have
 	   set LAST's BINFO_VTABLE yet.  We'll extract the actual vptr in
 	   binfo_ctor_vtable after everything's been set up.  */
@@ -7351,8 +7341,9 @@ build_vtbl_initializer (tree binfo,
 {
   tree v, b;
   tree vfun_inits;
-  tree vbase;
   vtbl_init_data vid;
+  unsigned ix;
+  tree vbinfo;
 
   /* Initialize VID.  */
   memset (&vid, 0, sizeof (vid));
@@ -7375,12 +7366,12 @@ build_vtbl_initializer (tree binfo,
   VARRAY_TREE_INIT (vid.fns, 32, "fns");
   /* Add the vcall and vbase offset entries.  */
   build_vcall_and_vbase_vtbl_entries (binfo, &vid);
+  
   /* Clear BINFO_VTABLE_PATH_MARKED; it's set by
      build_vbase_offset_vtbl_entries.  */
-  for (vbase = CLASSTYPE_VBASECLASSES (t); 
-       vbase; 
-       vbase = TREE_CHAIN (vbase))
-    BINFO_VTABLE_PATH_MARKED (TREE_VALUE (vbase)) = 0;
+  for (ix = 0; (vbinfo = VEC_iterate
+		(tree, CLASSTYPE_VBASECLASSES (t), ix)); ix++)
+    BINFO_VTABLE_PATH_MARKED (vbinfo) = 0;
 
   /* If the target requires padding between data entries, add that now.  */
   if (TARGET_VTABLE_DATA_ENTRY_DISTANCE > 1)

gcc/cp/cp-tree.h

@@ -27,8 +27,8 @@ Boston, MA 02111-1307, USA.  */
 #include "function.h"
 #include "hashtab.h"
 #include "splay-tree.h"
+#include "vec.h"
 #include "varray.h"
-
 #include "c-common.h"
 #include "name-lookup.h"
 
@@ -1017,6 +1017,8 @@ struct lang_type_header GTY(())
   BOOL_BITFIELD has_const_assign_ref : 1;
 };
 
+DEF_VEC_P (tree);
+
 /* This structure provides additional information above and beyond
    what is provide in the ordinary tree_type.  In the past, we used it
    for the types of class types, template parameters types, typename
@@ -1087,7 +1089,7 @@ struct lang_type_class GTY(())
   tree vcall_indices;
   tree vtables;
   tree typeinfo_var;
-  tree vbases;
+  VEC (tree) *vbases;
   binding_table nested_udts;
   tree as_base;
   tree pure_virtuals;
@@ -1305,7 +1307,7 @@ struct lang_type GTY(())
 #define CLASSTYPE_PRIMARY_BINFO(NODE) \
   (LANG_TYPE_CLASS_CHECK (NODE)->primary_base)
 
-/* A chain of BINFOs for the direct and indirect virtual base classes
+/* A vector 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.)  */
@@ -4121,6 +4123,7 @@ extern tree context_for_name_lookup		(tree);
 extern tree lookup_conversions			(tree);
 extern tree binfo_for_vtable			(tree);
 extern tree binfo_from_vbase			(tree);
+extern tree binfo_for_vbase			(tree, tree);
 extern tree look_for_overrides_here		(tree, tree);
 extern int check_final_overrider		(tree, tree);
 extern tree dfs_walk                            (tree,

gcc/cp/decl.c

@@ -9044,7 +9044,7 @@ xref_basetypes (tree ref, tree base_list)
   /* In the declaration `A : X, Y, ... Z' we mark all the types
      (A, X, Y, ..., Z) so we can check for duplicates.  */
   tree *basep;
-
+  unsigned max_vbases = 0;
   int i;
   enum tag_types tag_code;
 
@@ -9093,6 +9093,8 @@ xref_basetypes (tree ref, tree base_list)
 	  tree basetype = TREE_VALUE (base_list);
 	  tree base_binfo;
 	  
+	  if (via_virtual)
+	    max_vbases++;
 	  if (access == access_default_node)
 	    /* The base of a derived struct is public by default.  */
 	    access = (tag_code == class_type
@@ -9169,6 +9171,8 @@ xref_basetypes (tree ref, tree base_list)
 	     	 base as well.  */
 	      TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (ref)
 		|= TYPE_BASE_CONVS_MAY_REQUIRE_CODE_P (basetype);
+	      max_vbases += VEC_length
+		(tree, CLASSTYPE_VBASECLASSES (basetype));
 	    }
 	  i++;
 	}
@@ -9176,6 +9180,8 @@ xref_basetypes (tree ref, tree base_list)
 	TREE_VEC_LENGTH (accesses) = TREE_VEC_LENGTH (binfos) = i;
       else
 	BINFO_BASEACCESSES (binfo) = BINFO_BASETYPES (binfo) = NULL_TREE;
+      if (max_vbases)
+	CLASSTYPE_VBASECLASSES (ref) = VEC_alloc (tree, max_vbases);
       
       if (i > 1)
 	{
@@ -9189,7 +9195,6 @@ xref_basetypes (tree ref, tree base_list)
   /* Copy the base binfos, collect the virtual bases and set the
      inheritance order chain.  */
   copy_base_binfos (TYPE_BINFO (ref), ref, NULL_TREE);
-  CLASSTYPE_VBASECLASSES (ref) = nreverse (CLASSTYPE_VBASECLASSES (ref));
 
   if (TYPE_FOR_JAVA (ref))
     {

gcc/cp/init.c

@@ -468,9 +468,12 @@ sort_mem_initializers (tree t, tree mem_inits)
      TREE_VALUE will be the constructor arguments, or NULL if no
      explicit initialization was provided.  */
   sorted_inits = NULL_TREE;
+  
   /* Process the virtual bases.  */
-  for (base = CLASSTYPE_VBASECLASSES (t); base; base = TREE_CHAIN (base))
-    sorted_inits = tree_cons (TREE_VALUE (base), NULL_TREE, sorted_inits);
+  for (i = 0; (base = VEC_iterate
+	       (tree, CLASSTYPE_VBASECLASSES (t), i)); i++)
+    sorted_inits = tree_cons (base, NULL_TREE, sorted_inits);
+  
   /* Process the direct bases.  */
   for (i = 0; i < CLASSTYPE_N_BASECLASSES (t); ++i)
     {
@@ -988,13 +991,7 @@ expand_member_init (tree name)
       /* Look for a virtual base -- unless the direct base is itself
 	 virtual.  */
       if (!direct_binfo || !TREE_VIA_VIRTUAL (direct_binfo))
-	{
-	  virtual_binfo 
-	    = purpose_member (basetype,
-			      CLASSTYPE_VBASECLASSES (current_class_type));
-	  if (virtual_binfo)
-	    virtual_binfo = TREE_VALUE (virtual_binfo);
-	}
+	virtual_binfo = binfo_for_vbase (basetype, current_class_type);
 
       /* [class.base.init]
 	 
@@ -2874,27 +2871,23 @@ push_base_cleanups (void)
   /* Run destructors for all virtual baseclasses.  */
   if (TYPE_USES_VIRTUAL_BASECLASSES (current_class_type))
     {
-      tree vbases;
       tree cond = (condition_conversion
 		   (build (BIT_AND_EXPR, integer_type_node,
 			   current_in_charge_parm,
 			   integer_two_node)));
 
-      vbases = CLASSTYPE_VBASECLASSES (current_class_type);
-      /* The CLASSTYPE_VBASECLASSES list is in initialization
+      /* The CLASSTYPE_VBASECLASSES vector is in initialization
 	 order, which is also the right order for pushing cleanups.  */
-      for (; vbases;
-	   vbases = TREE_CHAIN (vbases))
+      for (i = 0; (binfos = VEC_iterate
+		   (tree, CLASSTYPE_VBASECLASSES (current_class_type), i));
+	   i++)
 	{
-	  tree vbase = TREE_VALUE (vbases);
-	  tree base_type = BINFO_TYPE (vbase);
-
-	  if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (base_type))
+	  if (TYPE_HAS_NONTRIVIAL_DESTRUCTOR (BINFO_TYPE (binfos)))
 	    {
 	      expr = build_special_member_call (current_class_ref, 
 						base_dtor_identifier,
 						NULL_TREE,
-						vbase,
+						binfos,
 						(LOOKUP_NORMAL 
 						 | LOOKUP_NONVIRTUAL));
 	      expr = build (COND_EXPR, void_type_node, cond,
@@ -2948,17 +2941,19 @@ push_base_cleanups (void)
 tree
 build_vbase_delete (tree type, tree decl)
 {
-  tree vbases = CLASSTYPE_VBASECLASSES (type);
+  unsigned ix;
+  tree binfo;
   tree result;
   tree addr = build_unary_op (ADDR_EXPR, decl, 0);
 
   my_friendly_assert (addr != error_mark_node, 222);
 
-  for (result = convert_to_void (integer_zero_node, NULL);
-       vbases; vbases = TREE_CHAIN (vbases))
+  result = convert_to_void (integer_zero_node, NULL);
+  for (ix = 0; (binfo = VEC_iterate
+		(tree, CLASSTYPE_VBASECLASSES (type), ix)); ix++)
     {
       tree base_addr = convert_force
-	(build_pointer_type (BINFO_TYPE (TREE_VALUE (vbases))), addr, 0);
+	(build_pointer_type (BINFO_TYPE (binfo)), addr, 0);
       tree base_delete = build_delete
 	(TREE_TYPE (base_addr), base_addr, sfk_base_destructor,
 	 LOOKUP_NORMAL|LOOKUP_DESTRUCTOR, 0);

gcc/cp/method.c

@@ -523,17 +523,17 @@ do_build_copy_constructor (tree fndecl)
       tree member_init_list = NULL_TREE;
       int cvquals = cp_type_quals (TREE_TYPE (parm));
       int i;
+      tree binfo;
 
       /* Initialize all the base-classes with the parameter converted
 	 to their type so that we get their copy constructor and not
 	 another constructor that takes current_class_type.  We must
 	 deal with the binfo's directly as a direct base might be
 	 inaccessible due to ambiguity.  */
-      for (t = CLASSTYPE_VBASECLASSES (current_class_type); t;
-	   t = TREE_CHAIN (t))
+      for (i = 0; (binfo = VEC_iterate
+		   (tree, CLASSTYPE_VBASECLASSES (current_class_type), i));
+	   i++)
 	{
-	  tree binfo = TREE_VALUE (t);
-	  
 	  member_init_list 
 	    = tree_cons (binfo,
 			 build_tree_list (NULL_TREE,

gcc/cp/search.c

@@ -1921,7 +1921,8 @@ dfs_get_pure_virtuals (tree binfo, void *data)
 void
 get_pure_virtuals (tree type)
 {
-  tree vbases;
+  unsigned ix;
+  tree binfo;
 
   /* Clear the CLASSTYPE_PURE_VIRTUALS list; whatever is already there
      is going to be overridden.  */
@@ -1938,14 +1939,12 @@ get_pure_virtuals (tree type)
   /* Put the pure virtuals in dfs order.  */
   CLASSTYPE_PURE_VIRTUALS (type) = nreverse (CLASSTYPE_PURE_VIRTUALS (type));
 
-  for (vbases = CLASSTYPE_VBASECLASSES (type); 
-       vbases; 
-       vbases = TREE_CHAIN (vbases))
+  for (ix = 0; (binfo = VEC_iterate
+		(tree, CLASSTYPE_VBASECLASSES (type), ix)); ix++)
     {
       tree virtuals;
-
-      for (virtuals = BINFO_VIRTUALS (TREE_VALUE (vbases));
-	   virtuals;
+      
+      for (virtuals = BINFO_VIRTUALS (binfo); virtuals;
 	   virtuals = TREE_CHAIN (virtuals))
 	{
 	  tree base_fndecl = BV_FN (virtuals);
@@ -2532,10 +2531,8 @@ copied_binfo (tree binfo, tree here)
       for (t = here; BINFO_INHERITANCE_CHAIN (t);
 	   t = BINFO_INHERITANCE_CHAIN (t))
 	continue;
-      
-      result = purpose_member (BINFO_TYPE (binfo),
-			       CLASSTYPE_VBASECLASSES (BINFO_TYPE (t)));
-      result = TREE_VALUE (result);
+
+      result = binfo_for_vbase (BINFO_TYPE (binfo), BINFO_TYPE (t));
     }
   else if (BINFO_INHERITANCE_CHAIN (binfo))
     {
@@ -2566,6 +2563,19 @@ copied_binfo (tree binfo, tree here)
   return result;
 }
 
+tree
+binfo_for_vbase (tree base, tree t)
+{
+  unsigned ix;
+  tree binfo;
+  
+  for (ix = 0; (binfo = VEC_iterate
+		(tree, CLASSTYPE_VBASECLASSES (t), ix)); ix++)
+    if (BINFO_TYPE (binfo) == base)
+      return binfo;
+  return NULL;
+}
+
 /* BINFO is some base binfo of HERE, within some other
    hierarchy. Return the equivalent binfo, but in the hierarchy
    dominated by HERE.  This is the inverse of copied_binfo.  If BINFO
@@ -2579,12 +2589,9 @@ original_binfo (tree binfo, tree here)
   if (BINFO_TYPE (binfo) == BINFO_TYPE (here))
     result = here;
   else if (TREE_VIA_VIRTUAL (binfo))
-    {
-      result = purpose_member (BINFO_TYPE (binfo),
-			       CLASSTYPE_VBASECLASSES (BINFO_TYPE (here)));
-      if (result)
-	result = TREE_VALUE (result);
-    }
+    result = (CLASSTYPE_VBASECLASSES (BINFO_TYPE (here))
+	      ? binfo_for_vbase (BINFO_TYPE (binfo), BINFO_TYPE (here))
+	      : NULL_TREE);
   else if (BINFO_INHERITANCE_CHAIN (binfo))
     {
       tree base_binfos;

gcc/cp/tree.c

@@ -571,8 +571,8 @@ canonical_type_variant (tree t)
    derived TYPE. PREV is the previous binfo, whose TREE_CHAIN we make
    point to this binfo. We return the last BINFO created.
 
-   The CLASSTYPE_VBASECLASSES list of T is constructed in reverse
-   order (pre-order, depth-first, right-to-left). You must nreverse it.
+   The CLASSTYPE_VBASECLASSES vector of T is constructed in the correct
+   order.
 
    The BINFO_INHERITANCE of a virtual base class points to the binfo
    og the most derived type.
@@ -613,12 +613,7 @@ copy_base_binfos (tree binfo, tree t, tree prev)
 	  BINFO_DEPENDENT_BASE_P (new_binfo) = 1;
 	}
       else if (TREE_VIA_VIRTUAL (base_binfo))
-	{
-	  new_binfo = purpose_member (BINFO_TYPE (base_binfo),
-				      CLASSTYPE_VBASECLASSES (t));
-	  if (new_binfo)
-	    new_binfo = TREE_VALUE (new_binfo);
-	}
+	new_binfo = binfo_for_vbase (BINFO_TYPE (base_binfo), t);
       
       if (!new_binfo)
 	{
@@ -628,9 +623,7 @@ copy_base_binfos (tree binfo, tree t, tree prev)
 	  prev = copy_base_binfos (new_binfo, t, prev);
 	  if (TREE_VIA_VIRTUAL (base_binfo))
 	    {
-	      CLASSTYPE_VBASECLASSES (t)
-		= tree_cons (BINFO_TYPE (new_binfo), new_binfo,
-			     CLASSTYPE_VBASECLASSES (t));
+	      VEC_quick_push (tree, CLASSTYPE_VBASECLASSES (t), new_binfo);
 	      TREE_VIA_VIRTUAL (new_binfo) = 1;
 	      BINFO_INHERITANCE_CHAIN (new_binfo) = TYPE_BINFO (t);
 	    }