re PR c++/48481 (C++ overloading memory hog)

	PR c++/48481
	* call.c (build_user_type_conversion_1): Use lookup_fnfields_slot.
	Release unused vector.

From-SVN: r172162

gcc/cp/ChangeLog

 2011-04-07  Jason Merrill  <jason@redhat.com>
 
+	PR c++/48481
+	* call.c (build_user_type_conversion_1): Use lookup_fnfields_slot.
+	Release unused vector.
+
 	PR c++/48451
 	* pt.c (fn_type_unification): Don't clear incomplete pack flag.
 	(type_unification_real): Clear it here instead.

gcc/cp/call.c

@@ -3249,7 +3249,9 @@ build_user_type_conversion_1 (tree totype, tree expr, int flags)
 	      || !DERIVED_FROM_P (totype, fromtype));
 
   if (MAYBE_CLASS_TYPE_P (totype))
-    ctors = lookup_fnfields (totype, complete_ctor_identifier, 0);
+    /* Use lookup_fnfields_slot instead of lookup_fnfields to avoid
+       creating a garbage BASELINK; constructors can't be inherited.  */
+    ctors = lookup_fnfields_slot (totype, complete_ctor_identifier);
 
   if (MAYBE_CLASS_TYPE_P (fromtype))
     {
@@ -3281,7 +3283,6 @@ build_user_type_conversion_1 (tree totype, tree expr, int flags)
   if (ctors)
     {
       int ctorflags = flags;
-      ctors = BASELINK_FUNCTIONS (ctors);
 
       first_arg = build_int_cst (build_pointer_type (totype), 0);
 
@@ -3389,7 +3390,11 @@ build_user_type_conversion_1 (tree totype, tree expr, int flags)
 
   candidates = splice_viable (candidates, pedantic, &any_viable_p);
   if (!any_viable_p)
-    return NULL;
+    {
+      if (args)
+	release_tree_vector (args);
+      return NULL;
+    }
 
   cand = tourney (candidates);
   if (cand == 0)