$ git clone -n https://src.fedoraproject.org/rpms/binutils.git /var/lib/mock/f41-build-1057112-19395/root/chroot_tmpdir/scmroot/binutils
Cloning into '/var/lib/mock/f41-build-1057112-19395/root/chroot_tmpdir/scmroot/binutils'...
$ git fetch origin 27b8ab3195d470546c3cbf37a6baf878cc216160:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/binutils
 * [new ref]         27b8ab3195d470546c3cbf37a6baf878cc216160 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 27b8ab3 Rebase to commit 6b19a26ee12.  (Which brings in --rosegment support).