anchor.diff:                              {non_unique_send_list, ToSend}),
                  ?DBG_ASSERT2(length(ToReq) =:= length(lists:usort(ToReq)),
                               {non_unique_req_list, ToReq}),
  +               ?ASSERT2(ToReq =:= [], {req_nonempty, ToReq}),
                  send_local(OwnerL, {request_resolve, SID,
                                      {key_upd_send, DestRRPid, ToSend, ToReq},
                                      [{from_my_node, ?IIF(Initiator, 1, 0)},
  
positive.code:                end,
  
             % let the non-initiator's rr_recon process identify the remaining keys
             Req2Count = gb_trees:size(OtherDBChunk1),
             ToReq2 = compress_k_list(OtherDBChunk1, OtherDBChunkOrig,
                                      SigSize, VSize, 0, [], 0, 0),
             % the non-initiator will use key_upd_send and we must thus increase
             % the number of resolve processes here!
  
negative.code:     {NHashes, OBucketHashes, OBucketTree, SigSize, VSize} =
          merkle_resolve_retrieve_leaf_hashes(Hashes, P1EOneLeaf, MyMaxItemsCount, BucketSizeBits),
      {ToSend1, ToReq1, OBucketTree1} =
          get_full_diff(MyBuckets, OBucketTree, ToSend, [], SigSize, VSize),
      ReqTree = lists:foldl(fun(KeyBin, Acc) ->
                                    gb_trees:enter(KeyBin, 0, Acc)
                            end, OBucketTree1, ToReq1),
      ToResolve1 = [compress_k_list(ReqTree, OBucketHashes, SigSize, VSize,
                                    0, [], 0, 0) | ToResolve],
      ResolveNonEmptyAcc1 =
          ?IIF(gb_trees:size(ReqTree) =/= 0, true, ResolveNonEmptyAcc),
      {NHashes, ToSend1, ToReq, ToResolve1, ResolveNonEmptyAcc1, NLeafNAcc}.
  
  %% @doc Helper for the final resolve step during merkle sync.
  -spec merkle_resolve(
  