$ git clone -n https://src.fedoraproject.org/rpms/perl-Devel-GoFaster.git /var/lib/mock/f41-build-816654-150311/root/chroot_tmpdir/scmroot/perl-Devel-GoFaster
Cloning into '/var/lib/mock/f41-build-816654-150311/root/chroot_tmpdir/scmroot/perl-Devel-GoFaster'...
$ git fetch origin 988cf7c220b47d30401dd1f85f6ca46c52a438db:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/perl-Devel-GoFaster
 * [new ref]         988cf7c220b47d30401dd1f85f6ca46c52a438db -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 988cf7c Perl 5.40 rebuild