$ git clone -n https://src.fedoraproject.org/rpms/ghc-fixed.git /var/lib/mock/f38-build-side-42-init-devel-837203-28399/root/chroot_tmpdir/scmroot/ghc-fixed
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-837203-28399/root/chroot_tmpdir/scmroot/ghc-fixed'...
$ git fetch origin 38fe2c8df42907b64403336c79ab27431e19a6d3:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-fixed
 * [new ref]         38fe2c8df42907b64403336c79ab27431e19a6d3 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 38fe2c8 Convert to %autorelease and %autochangelog