$ git clone -n https://src.fedoraproject.org/rpms/rust-portable-atomic-util.git /var/lib/mock/f45-build-43949-809/root/chroot_tmpdir/scmroot/rust-portable-atomic-util
Cloning into '/var/lib/mock/f45-build-43949-809/root/chroot_tmpdir/scmroot/rust-portable-atomic-util'...
$ git fetch origin a22d16ba185a92462fb54d438dbe8fa0d479b4ec:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-portable-atomic-util
 * [new ref]         a22d16ba185a92462fb54d438dbe8fa0d479b4ec -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a22d16b Update to version 0.2.8; Fixes RHBZ#2528649