$ git clone -n https://src.fedoraproject.org/rpms/rust-libloading.git /var/lib/mock/f42-build-side-1-3537763-46560/root/chroot_tmpdir/scmroot/rust-libloading
Cloning into '/var/lib/mock/f42-build-side-1-3537763-46560/root/chroot_tmpdir/scmroot/rust-libloading'...
$ git fetch origin ca42e1ce612a7c4dd5a62c9fa25fcf70c3938df1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-libloading
 * [new ref]         ca42e1ce612a7c4dd5a62c9fa25fcf70c3938df1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at ca42e1c Update to version 0.8.8; Fixes RHBZ#2368666