$ git clone -n https://src.fedoraproject.org/rpms/rust-cargo-c.git /var/lib/mock/f38-build-side-43-rust-devel-1405513-31258/root/chroot_tmpdir/scmroot/rust-cargo-c
Cloning into '/var/lib/mock/f38-build-side-43-rust-devel-1405513-31258/root/chroot_tmpdir/scmroot/rust-cargo-c'...
$ git fetch origin 65c67f3c4d2cea0323cd6d94f3867c97c5f62329:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-cargo-c
 * [new ref]         65c67f3c4d2cea0323cd6d94f3867c97c5f62329 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 65c67f3 Adapt cargo-c macros to support the same flags as the cargo counterparts