$ git clone -n https://src.fedoraproject.org/rpms/rust-cxxbridge-macro.git /var/lib/mock/f40-build-2640581-66405/root/chroot_tmpdir/scmroot/rust-cxxbridge-macro
Cloning into '/var/lib/mock/f40-build-2640581-66405/root/chroot_tmpdir/scmroot/rust-cxxbridge-macro'...
$ git fetch origin 62b0b0732a067667f99f485d7b93be2b1f97ce35:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-cxxbridge-macro
 * [new ref]         62b0b0732a067667f99f485d7b93be2b1f97ce35 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 62b0b07 Update to version 1.0.120 (rhbz#2271161)