$ git clone -n https://src.fedoraproject.org/rpms/ghc-base-prelude.git /var/lib/mock/f41-build-837452-159151/root/chroot_tmpdir/scmroot/ghc-base-prelude
Cloning into '/var/lib/mock/f41-build-837452-159151/root/chroot_tmpdir/scmroot/ghc-base-prelude'...
$ git fetch origin 3cd2f2f2e1b97be162bdc7717da9e073167cb0bf:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-base-prelude
 * [new ref]         3cd2f2f2e1b97be162bdc7717da9e073167cb0bf -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 3cd2f2f https://hackage.haskell.org/package/base-prelude-1.6.1.1/changelog