$ git clone -n https://src.fedoraproject.org/rpms/binutils.git /var/lib/mock/f40-build-794227-139510/root/chroot_tmpdir/scmroot/binutils
Cloning into '/var/lib/mock/f40-build-794227-139510/root/chroot_tmpdir/scmroot/binutils'...
$ git fetch origin a363b071f49f3d9826ed52dadf92bf7c025d6d95:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/binutils
 * [new ref]         a363b071f49f3d9826ed52dadf92bf7c025d6d95 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a363b07 Rebase to commit 6549a232d25585800752007f699fb7db9fe70883