$ git clone -n https://src.fedoraproject.org/rpms/memtest86+.git /var/lib/mock/f40-build-772864-126652/root/chroot_tmpdir/scmroot/memtest86+
Cloning into '/var/lib/mock/f40-build-772864-126652/root/chroot_tmpdir/scmroot/memtest86+'...
$ git fetch origin 60e96a392c3587c0b9bc8f2585f8ee2dd71cbee2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/memtest86+
 * [new ref]         60e96a392c3587c0b9bc8f2585f8ee2dd71cbee2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 60e96a3 Update to 7.00