$ git clone -n https://src.fedoraproject.org/forks/u2fsdgvkx1/rpms/gcc.git /var/lib/mock/f45-build-282-169/root/chroot_tmpdir/scmroot/gcc
Cloning into '/var/lib/mock/f45-build-282-169/root/chroot_tmpdir/scmroot/gcc'...
$ git fetch origin 79ccd4dc797431b0e0a4873730b27bdd75324583:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/forks/u2fsdgvkx1/rpms/gcc
 * [new ref]         79ccd4dc797431b0e0a4873730b27bdd75324583 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 79ccd4d gcc: fix RVA23 multilib library directories