$ git clone -n https://src.fedoraproject.org/rpms/gap-pkg-guava.git /var/lib/mock/f40-build-1997116-44107/root/chroot_tmpdir/scmroot/gap-pkg-guava
Cloning into '/var/lib/mock/f40-build-1997116-44107/root/chroot_tmpdir/scmroot/gap-pkg-guava'...
$ git fetch origin f6c556973e661235a7db258881b0969599a7bccf:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gap-pkg-guava
 * [new ref]         f6c556973e661235a7db258881b0969599a7bccf -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f6c5569 Use a more reliable way of detecting CPU features