anchor.diff:      N := FNodes.HeuristedPool.First.Next;
       FNodes.HeuristedPool.First.Next := Node;
       Node.Next := N;
  +    Node.Prev := @FNodes.HeuristedPool.First;
       N.Prev := Node;
     end;
   
  
positive.code:           begin
              N := FNodes.HeuristedPool.First.Next;
              FNodes.HeuristedPool.First.Next := Node;
            end;
            Node.Next := N;
            N.Prev := Node;
  
negative.code:           Node.NodeInfo := ({$ifdef CPUX86}Node.{$endif}NodeInfo and FLAGS_CLEAN_MASK) or Cardinal(Mask shl 3);
          {$endif}
  
          // sort value and heuristed pool
          SortValue := Node.SortValue;
          if (SortValue >= NATTANABLE_LENGTH_LIMIT) then
          begin
  