diff --git a/gtests/net/packetdrill/parser.y b/gtests/net/packetdrill/parser.y
index df9f581772f3f2ee503e0d2eb6e54788cffadb38..47eded23393dc141912b265cc4082849b357bcba 100644
--- a/gtests/net/packetdrill/parser.y
+++ b/gtests/net/packetdrill/parser.y
@@ -3348,7 +3348,7 @@ accept_filter_arg
 	$$ = new_expression(EXPR_ACCEPT_FILTER_ARG);
 	$$->value.accept_filter_arg = calloc(1, sizeof(struct accept_filter_arg_expr));
 	$$->value.accept_filter_arg->af_name = $2;
-	$$->value.accept_filter_arg->af_arg = NULL;
+	$$->value.accept_filter_arg->af_arg = new_expression(EXPR_ELLIPSIS);
 #else
 	$$ = NULL;
 #endif