anchor.diff:      gen_server:cast(self(), start),
       {ok, State}.
   
  -
  +-type is_orphan_msg() :: {is_orphan, object_type(), object_name(),
  +                          node(), volume_name()}.
  +-spec handle_call(is_orphan_msg(), from(), state()) -> {reply, boolean(), state()};
  +                 (dbg_state_msg(), from(), state()) -> {reply, state(), state()}.
   handle_call({is_orphan, Type, ObjName, Node, Vol}, _, S) ->
       S1 = S#state{last_response_time = now()},
       {reply, check_is_orphan(S, Type, ObjName, Node, Vol), S1};
  
positive.code: 
  %% ===================================================================
  %% gen_server callbacks
  
  init({Root, DeletedAges}) ->
      % Ensure only one gc process is running at a time.  We don't use a
      % named process to implement uniqueness so that our message queue
  
negative.code: %% ===================================================================
  %% gen_server callback stubs
  
  -spec terminate(term(), state()) -> ok.
  terminate(_Reason, _S) -> ok.
  
  -spec code_change(term(), state(), term()) -> {ok, state()}.
  code_change(_OldVsn, State, _Extra) ->
      {ok, State}.
  
  -spec format_status(term(), [term()]) -> [term()].
  format_status(_Opt, [_PDict, S]) ->
      [{data, [{"State", [{phase, S#state.phase}]}]}].
  
  