Improve abstraction of ref lock/write.

diff --git a/merge-tree.c b/merge-tree.c
index cc7b5bd891a213adcc18a44fb9d9ff6d7946cbb3..9dcaab7a85fdb63b2140923a95b216917bfc0993 100644 (file)
--- a/merge-tree.c
+++ b/merge-tree.c
@@ -149,7 +149,7 @@ static void *get_tree_descriptor(struct tree_desc *desc, const char *rev)
        unsigned char sha1[20];
        void *buf;
 
-       if (get_sha1(rev, sha1) < 0)
+       if (get_sha1(rev, sha1))
                die("unknown rev %s", rev);
        buf = fill_tree_descriptor(desc, sha1);
        if (!buf)