anchor.diff:  
   -spec rtms_of_same_dht_node(rtms()) -> boolean().
   rtms_of_same_dht_node(InRTMs) ->
  -    Groups = lists:usort([catch(pid_groups:group_of(
  -                                  comm:make_local(element(1,get_rtmpid(X)))))
  +    GetGroups = lists:usort([pid_groups:group_of(
  +                            comm:make_local(element(1,get_rtmpid(X))))
                             || X <- InRTMs, unknown =/= get_rtmpid(X)]),
  +    %% group_of may return failed, don't include these
  +    Groups = [ X || X <- GetGroups, X =/= failed ],
       case length(Groups) of
           4 -> false;
           _ ->
  
positive.code:             RTMs = tx_state:get_rtms(TxState),
              Role = state_get_role(State),
              ValidAccs = [ X || {X} <- rtms_get_accpids(RTMs)],
              {_, _, ThisRTMsNumber, _} = lists:keyfind({comm:this()}, 2, RTMs),
  
              %% add ourselves as learner and
              %% trigger paxos proposers for new round with own proposal 'abort'
  
negative.code:                           ok
                    end
                end || ItemId <- TxItemIDs ]
              end
          end,
      State;
  
  