anchor.diff:              Active = ?SETS:add_element(FirstLid, ?SETS:new()),
               Blocked = ?SETS:new(),
               State = state:empty(),
  -            Context = #context{active=Active, state=State, blocked=Blocked},
  +            Context = #context{active=Active, state=State,
  +                blocked=Blocked, actions=[]},
               %% Interleave using driver
               Ret = driver(Context, ReplayState),
               %% Cleanup
  
positive.code:         end,
      {NewContext, Insert} = run_no_block(Context, Next),
      insert_states(State, Insert),
      check_for_errors(NewContext, Actions).
  
  %% Handle four possible cases:
  %% - An error occured during the execution of the last process =>
  
negative.code: %%   Terminate the run without errors.
  %% - There exists at least one active process =>
  %%   Continue run.
  check_for_errors(#context{error=NewError, actions=Actions, active=NewActive,
                            blocked=NewBlocked} = NewContext) ->
      case NewError of
          ?NO_ERROR ->
              case ?SETS:size(NewActive) of
  