diff --git a/src/arg.c b/src/arg.c
index 9e551fb..ca914fa 100644
--- a/src/arg.c
+++ b/src/arg.c
@@ -72,9 +72,11 @@
 	struct arg_list *new;
 
 	new = arg_list_clone(orig);
-	new->arg = arg;
-	new->arg_pos = pos;
-	LIST_ADDQ(&orig->list, &new->list);
+	if (new) {
+		new->arg = arg;
+		new->arg_pos = pos;
+		LIST_ADDQ(&orig->list, &new->list);
+	}
 	return new;
 }