$ git clone -n https://src.fedoraproject.org/rpms/ghc-IOSpec.git /var/lib/mock/f38-build-side-42-init-devel-934127-28751/root/chroot_tmpdir/scmroot/ghc-IOSpec
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-934127-28751/root/chroot_tmpdir/scmroot/ghc-IOSpec'...
$ git fetch origin 546f472e11e57bdce1d86b0ebc42ac6a12d59bb4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-IOSpec
 * [new ref]         546f472e11e57bdce1d86b0ebc42ac6a12d59bb4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 546f472 Convert to %autorelease and %autochangelog