describe: fix off-by-one error in --abbrev=40 handling

diff --git a/builtin-diff.c b/builtin-diff.c
index 40e5c96f30e3d638c09b276805158bdba3ddde58..874f773421620642425e67f650de2a34396f1c0f 100644 (file)
--- a/builtin-diff.c
+++ b/builtin-diff.c
@@ -69,7 +69,7 @@ static void stuff_change(struct diff_options *opt,
        struct diff_filespec *one, *two;
 
        if (!is_null_sha1(old_sha1) && !is_null_sha1(new_sha1) &&
-           !memcmp(old_sha1, new_sha1, 20))
+           !hashcmp(old_sha1, new_sha1))
                return;
 
        if (opt->reverse_diff) {