$ git clone -n https://src.fedoraproject.org/rpms/ghc-concatenative.git /var/lib/mock/f41-build-837474-159153/root/chroot_tmpdir/scmroot/ghc-concatenative
Cloning into '/var/lib/mock/f41-build-837474-159153/root/chroot_tmpdir/scmroot/ghc-concatenative'...
$ git fetch origin cac82ab723529ef228aab23ae3bd99a953e2802f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-concatenative
 * [new ref]         cac82ab723529ef228aab23ae3bd99a953e2802f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at cac82ab bump release