anchor.diff:  filter_dead_node(RT, DeadPid) -> 
       % find the node id of DeadPid and delete it from the RT
       case [N || N <- internal_to_list(RT), node:pidX(N) =:= DeadPid] of
  -        [Node] -> entry_delete(node:id(Node), RT);
  +        [Node] ->
  +            fd:unsubscribe(DeadPid),
  +            entry_delete(node:id(Node), RT)
  +            ;
           [] -> RT
       end
       .
  
positive.code: 
          false -> LocalRT
      end,
      update_fd(LocalRT, NewRT),
      rt_loop:set_rt(State, NewRT)
      ;
  
  
negative.code:             end,
              NewRT
              ;
          false ->
              add_fd(IntermediateRT),
              IntermediateRT
      end
      .
  
  