Index: gcc/testsuite/gcc.dg/pr27953.c
===================================================================
--- gcc/testsuite/gcc.dg/pr27953.c	(revision 0)
+++ gcc/testsuite/gcc.dg/pr27953.c	(revision 0)
@@ -0,0 +1,4 @@
+/* PR c/27953 */
+
+void foo(struct A a) {}  /* { dg-error "parameter list|definition|incomplete type" } */
+void foo() {}            /* { dg-error "redefinition" }
Index: gcc/c-decl.c
===================================================================
--- gcc/c-decl.c	(revision 116257)
+++ gcc/c-decl.c	(working copy)
@@ -6384,8 +6384,8 @@ store_parm_decls_oldstyle (tree fndecl, 
       tree type;
       for (parm = DECL_ARGUMENTS (fndecl),
 	     type = current_function_prototype_arg_types;
-	   parm || (type && (TYPE_MAIN_VARIANT (TREE_VALUE (type))
-			     != void_type_node));
+	   parm || (type && TREE_VALUE (type) != error_mark_node
+                   && (TYPE_MAIN_VARIANT (TREE_VALUE (type)) != void_type_node));
 	   parm = TREE_CHAIN (parm), type = TREE_CHAIN (type))
 	{
 	  if (parm == 0 || type == 0