$ git clone -n https://src.fedoraproject.org/rpms/erlang-gproc.git /var/lib/mock/f40-build-1777693-24803/root/chroot_tmpdir/scmroot/erlang-gproc
Cloning into '/var/lib/mock/f40-build-1777693-24803/root/chroot_tmpdir/scmroot/erlang-gproc'...
$ git fetch origin 34f4ff4aed8607be115e24393b789036793d7c63:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/erlang-gproc
 * [new ref]         34f4ff4aed8607be115e24393b789036793d7c63 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 34f4ff4 gproc ver. 0.9.1