$ git clone -n https://src.fedoraproject.org/rpms/rust-gio-sys.git /var/lib/mock/f42-build-side-1-3584777-46896/root/chroot_tmpdir/scmroot/rust-gio-sys
Cloning into '/var/lib/mock/f42-build-side-1-3584777-46896/root/chroot_tmpdir/scmroot/rust-gio-sys'...
$ git fetch origin b1a1375896ce7057c97a5ddeb1c6eda935de99da:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rust-gio-sys
 * [new ref]         b1a1375896ce7057c97a5ddeb1c6eda935de99da -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at b1a1375 Update to version 0.20.10; Fixes RHBZ#2365829