diff --git a/builtin/commit.c b/builtin/commit.c
index 8f2bebe..4f782a3 100644
--- a/builtin/commit.c
+++ b/builtin/commit.c
@@ -862,10 +862,7 @@
 	 */
 	discard_cache();
 	read_cache_from(index_file);
-	if (!active_cache_tree)
-		active_cache_tree = cache_tree();
-	if (cache_tree_update(active_cache_tree,
-			      active_cache, active_nr, 0, 0) < 0) {
+	if (update_main_cache_tree(0)) {
 		error(_("Error building trees"));
 		return 0;
 	}