thodg/got

diff --git a/lib/worktree.c b/lib/worktree.c
index c1378d1..3b9b6d5 100644
--- a/lib/worktree.c
+++ b/lib/worktree.c
@@ -2273,7 +2273,7 @@ got_worktree_commit(struct got_object_id **new_commit_id,
 	if (err)
 		goto done;
 	err = got_object_open_as_tree(&base_tree, repo,
-	    worktree->base_commit_id);
+	    base_commit->tree_id);
 	if (err)
 		goto done;