re PR c++/6255 (ICE with templatess)

        PR c++/6255
        * decl.c (lookup_name_real): Build a new TYPENAME_TYPE rather than
        modifying the old one.

From-SVN: r55352

gcc/cp/ChangeLog

+2002-07-10  Jason Merrill  <jason@redhat.com>
+
+	PR c++/6255
+	* decl.c (lookup_name_real): Build a new TYPENAME_TYPE rather than
+	modifying the old one.
+
 2002-07-09  Mark Mitchell  <mark@codesourcery.com>
 
 	* cp-tree.h (constructor_name_p): Declare it.

gcc/cp/decl.c

@@ -6072,7 +6072,13 @@ lookup_name_real (name, prefer_type, nonclass, namespaces_only)
 	      if (got_scope && got_scope != type
 		  && val && TREE_CODE (val) == TYPE_DECL
 		  && TREE_CODE (TREE_TYPE (val)) == TYPENAME_TYPE)
-		TYPE_CONTEXT (TREE_TYPE (val)) = got_scope;
+		{
+		  val = TREE_TYPE (val);
+		  val = build_typename_type (got_scope, name,
+					     TYPENAME_TYPE_FULLNAME (val),
+					     TREE_TYPE (val));
+		  val = TYPE_STUB_DECL (val);
+		}
 	    }
 	}
       else