$ git clone -n https://src.fedoraproject.org/rpms/rust-rdrand.git /var/lib/mock/f41-build-side-1-3136905-39784/root/chroot_tmpdir/scmroot/rust-rdrand
Cloning into '/var/lib/mock/f41-build-side-1-3136905-39784/root/chroot_tmpdir/scmroot/rust-rdrand'...
$ git fetch origin eab271c8914b128f55b0e6a81218ac016da326d9:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-rdrand
 * [new ref]         eab271c8914b128f55b0e6a81218ac016da326d9 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at eab271c Initial import (fedora#2310497)