diff --git a/cache-tree.c b/cache-tree.c
index 8c7e1258a4..25663825b5 100644
--- a/cache-tree.c
+++ b/cache-tree.c
@@ -385,7 +385,7 @@ static int update_one(struct cache_tree *it,
 		/*
 		 * "sub" can be an empty tree if all subentries are i-t-a.
 		 */
-		if (contains_ita && !oidcmp(oid, &empty_tree_oid))
+		if (contains_ita && is_empty_tree_oid(oid))
 			continue;
 
 		strbuf_grow(&buffer, entlen + 100);