$ git clone -n https://src.fedoraproject.org/rpms/rust-primal-slowsieve.git /var/lib/mock/f45-build-43981-809/root/chroot_tmpdir/scmroot/rust-primal-slowsieve
Cloning into '/var/lib/mock/f45-build-43981-809/root/chroot_tmpdir/scmroot/rust-primal-slowsieve'...
$ git fetch origin adc2765ae8b04dd258c685403638aef1d5125af0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-primal-slowsieve
 * [new ref]         adc2765ae8b04dd258c685403638aef1d5125af0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at adc2765 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild