$ git clone -n https://src.fedoraproject.org/rpms/mpich.git /var/lib/mock/f42-build-862269-170710/root/chroot_tmpdir/scmroot/mpich
Cloning into '/var/lib/mock/f42-build-862269-170710/root/chroot_tmpdir/scmroot/mpich'...
$ git fetch origin 48d3a0fdfdb6bc2959718eee2658658dbeac21c3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mpich
 * [new ref]         48d3a0fdfdb6bc2959718eee2658658dbeac21c3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 48d3a0f Version 4.2.2