$ git clone -n https://src.fedoraproject.org/rpms/ispc.git /var/lib/mock/f40-build-802787-144099/root/chroot_tmpdir/scmroot/ispc
Cloning into '/var/lib/mock/f40-build-802787-144099/root/chroot_tmpdir/scmroot/ispc'...
$ git fetch origin d7100a1cb99801a3866f8176e79277aecbb974d1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ispc
 * [new ref]         d7100a1cb99801a3866f8176e79277aecbb974d1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d7100a1 Don't build-require files outside of permitted directories