$ git clone -n https://gitee.com/mgb01105731/gmp.git /var/lib/mock/dist-an27-build-527187-79470/root/chroot_tmpdir/scmroot/gmp
Cloning into '/var/lib/mock/dist-an27-build-527187-79470/root/chroot_tmpdir/scmroot/gmp'...
$ git fetch origin a27:KOJI_FETCH_HEAD
From https://gitee.com/mgb01105731/gmp
 * [new branch]      a27        -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 8dfbf75 Init package