anchor.diff:        Passes =
           [ fun proplists:unfold/1
           , fun rename_equivalent/1
  -        , fun add_missing_getopt_defaults/1
           , fun(O) ->
                 add_missing_defaults([{verbosity, ?DEFAULT_VERBOSITY}], O)
             end
           , fun finalize_aux/1
  +        , fun add_missing_getopt_defaults/1
           , fun(O) ->
                 add_missing_defaults(
  -                [{ignore_error, []},
  +                [{dpor, optimal},
  +                 {ignore_error, []},
                    {non_racing_system, []},
  -                 {dpor, optimal},
                    {scheduling_bound_type, none},
                    {treat_as_normal, []}
                   ], O)
  
positive.code:       NewRest =
          case Value =/= bpor orelse proplists:is_defined(dpor, Acc ++ Rest) of
            true -> Rest;
            false ->
              Msg = "assuming '--dpor source'.",
              opt_warn(Msg, []),
              [{dpor, source}|Rest]
          end,
        finalize(NewRest, [Option|Acc]);
      MaybeInfinity
        when
          MaybeInfinity =:= interleaving_bound;
  
negative.code:       check_validity(Key, Value, [newest, oldest, round_robin]),
        finalize(Rest, [Option|Acc]);
      scheduling_bound ->
        ValidityCheck = {fun(V) -> V >= 0 end, "a non-negative integer"},
        check_validity(Key, Value, ValidityCheck),
        NewRest =
          case proplists:is_defined(scheduling_bound_type, Acc ++ Rest) of
            true -> Rest;
            false -> assume(scheduling_bound_type, simple, Rest)
          end,
        finalize(NewRest, [Option|Acc]);
      scheduling_bound_type ->
  