transaction = ref_transaction_begin(&err);
if (!transaction ||
- ref_transaction_update(transaction, ref->name, ref->new_sha1,
- ref->old_sha1, 0, check_old, msg, &err))
+ ref_transaction_update(transaction, ref->name,
+ ref->new_sha1,
+ check_old ? ref->old_sha1 : NULL,
+ 0, msg, &err))
goto fail;
ret = ref_transaction_commit(transaction, &err);