anchor.diff:  -spec rep_spawn(fun()) -> pid().
   
   rep_spawn(Fun) ->
  +    %% XXX: Possible race between `yield` message of child and
  +    %%      `spawn` message of parent.
       Pid = spawn(fun() -> rep_yield(), Fun() end),
       sched ! #sched{msg = spawn, pid = self(), misc = [Pid]},
       rep_yield(),
  
positive.code: stop(Reason) ->
      log:log("-----------------------~n"),
      log:log("Run terminated (~p).~n~n", [Reason]),
      case Reason of
          normal -> ?RET_NORMAL;
          _ -> ?RET_HEISENBUG
  
negative.code: %% Clean up state table.
  state_stop() ->
      ets:delete(state).
  
  %%%----------------------------------------------------------------------
  %%% Unit tests (to be moved)
  