$ git clone -n https://src.fedoraproject.org/rpms/xdffileio.git /var/lib/mock/f45-build-38675-727/root/chroot_tmpdir/scmroot/xdffileio
Cloning into '/var/lib/mock/f45-build-38675-727/root/chroot_tmpdir/scmroot/xdffileio'...
$ git fetch origin 62d42a9442a3be0f53d1d4779670e0cbd141cc5d:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/xdffileio
 * [new ref]         62d42a9442a3be0f53d1d4779670e0cbd141cc5d -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 62d42a9 FTBFS fix (rhbz#2505264)