$ git clone -n https://src.fedoraproject.org/rpms/emacs.git /var/lib/mock/f42-build-3496578-45897/root/chroot_tmpdir/scmroot/emacs
Cloning into '/var/lib/mock/f42-build-3496578-45897/root/chroot_tmpdir/scmroot/emacs'...
$ git fetch origin 60275486b2a3679571d34bc1115b2003356d6d02:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/emacs
 * [new ref]         60275486b2a3679571d34bc1115b2003356d6d02 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 6027548 Fix compilation errors due to insufficient compiler safety