$ git clone -n https://src.fedoraproject.org/rpms/imath.git /var/lib/mock/f41-build-852374-166334/root/chroot_tmpdir/scmroot/imath
Cloning into '/var/lib/mock/f41-build-852374-166334/root/chroot_tmpdir/scmroot/imath'...
$ git fetch origin b1a6feae061d5421320f4c46437dd347436a198c:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/imath
 * [new ref]         b1a6feae061d5421320f4c46437dd347436a198c -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b1a6fea Update to 3.1.12.