$ git clone -n https://src.fedoraproject.org/rpms/sip6.git /var/lib/mock/f40-build-731301-103849/root/chroot_tmpdir/scmroot/sip6
Cloning into '/var/lib/mock/f40-build-731301-103849/root/chroot_tmpdir/scmroot/sip6'...
$ git fetch origin f42ec26de17595d89076fd7edbfff54ff54873f3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/sip6
 * [new ref]         f42ec26de17595d89076fd7edbfff54ff54873f3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f42ec26 6.7.12