$ git clone -n https://github.com/fedora-riscv/rust.git /var/lib/mock/f38-build-side-42-init-devel-1723765-40798/root/chroot_tmpdir/scmroot/rust
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-1723765-40798/root/chroot_tmpdir/scmroot/rust'...
$ git fetch origin f557f621250c54101dc49d01aacf47ef4f968c95:KOJI_FETCH_HEAD
From https://github.com/fedora-riscv/rust
 * [new ref]         f557f621250c54101dc49d01aacf47ef4f968c95 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at f557f62 Fix building on riscv64.