anchor.diff:      {NewUPI_list3, Repairing_list3, RunEnv3} =
           case {NewUp, Repairing_list2} of
               {[], []} ->
  -                D_foo=[],
  +                D_foo=[d_foo1],
                   {NewUPI_list, [], RunEnv2};
               {[], [H|T]} when RelativeToServer == LastInNewUPI ->
                   %% The author is tail of the UPI list.  Let's see if
  
positive.code:                                     end,
                               Rel2;
                           {error, not_written} ->
  %%io:format(user, "fold ~p ~p not_written\n", [E, FLU]),
                               Rel
                       end
               end, Relation, [{E, FLU} || E <- NowEpochs, FLU <- Up]),
      SortedRel = lists:reverse(lists:sort(Rel2)),
  %%io:format(user, "zerf_find_last_common rel ~p\n", [SortedRel]),
      case [T || T={{E, OorI, Proj}, WrittenFLUs} <- SortedRel,
                 lists:sort(Proj#projection_v1.upi) == lists:sort(WrittenFLUs)
                 andalso
  
negative.code: 
      TentativeUPI = NewUPI_list3,
      TentativeRepairing = Repairing_list5,
      ?REACT({calc,?LINE,[{tent, TentativeUPI},{tent_rep, TentativeRepairing}]}),
  
      {NewUPI, NewRepairing} =
          if (CMode == ap_mode
              orelse
              (CMode == cp_mode andalso OldEpochNum == 0))
             andalso
             TentativeUPI == [] andalso TentativeRepairing /= [] ->
                  %% UPI is empty (not including witnesses), so grab
                  %% the first from the repairing list and make it the
                  %% only non-witness in the UPI.
  