anchor.diff:  foo32(Pid) ->
       %% Pid ! msg2
       sched:rep_send(Pid, msg2).
  +
  +-spec test4() -> no_return().
  +
  +test4() ->
  +    %% spawn(fun() -> foo4(Self) end)
  +    sched:rep_spawn(
  +      fun() ->
  +              spawn(fun() ->
  +                            link(whereis(sched)),
  +                            foo4()
  +                    end)
  +      end),
  +    %% receive _Any -> ok end
  +    sched:rep_receive(
  +      fun(Aux) ->
  +	      receive
  +		  _Any -> ok
  +	      after 0 -> Aux()
  +	      end
  +      end).
  +
  +foo4() ->
  +    %% receive _Any -> ok end
  +    sched:rep_receive(
  +      fun(Aux) ->
  +	      receive
  +		  _Any -> ok
  +	      after 0 -> Aux()
  +	      end
  +      end).
  +
  +-spec test5() -> no_return().
  +
  +test5() ->
  +    Self = self(),
  +    %% spawn(fun() -> foo1(Self) end)
  +    sched:rep_spawn(
  +      fun() ->
  +              spawn(fun() ->
  +                            link(whereis(sched)),
  +                            foo1(Self)
  +                    end)
  +      end),
  +    %% receive _Any -> ok end
  +    sched:rep_receive(
  +      fun(Aux) ->
  +	      receive
  +		  43 -> ok
  +	      after 0 -> Aux()
  +	      end
  +      end).
  
positive.code: -module(test_instr).
  -export([test1/0, test2/0, test3/0]).
  
  -spec test1() -> ok.
      
  test1() ->
      Self = self(),
      %% spawn(fun() -> foo1(Self) end)
      sched:rep_spawn(fun() -> spawn(fun() -> link(whereis(sched)), foo1(Self) end) end),
      %% receive _Any -> ok end
      sched:rep_receive(
        fun(Aux) ->
  
negative.code:     %% Pid ! 42
      sched:rep_send(Pid, 42).
  
  -spec test2() -> 'ok'.
  
  test2() ->
      %% spawn(fun() -> foo21 end)
      sched:rep_spawn(
        fun() -> 
                spawn(fun() ->
                              link(whereis(sched)),
                              foo21()
                      end)
        end),
      %% spawn(fun() -> foo22 end)
      sched:rep_spawn(
        fun() ->
                spawn(fun() ->
                              link(whereis(sched)),
                              foo22()
                      end)
        end),
      ok.
  
  foo21() ->
      %% spawn(fun() -> foo 22 end)
      sched:rep_spawn(
        fun() -> 
                spawn(fun() ->
                              link(whereis(sched)),
                              foo22()
                      end)
        end).
  
  foo22() ->
      42.
  
  -spec test3() -> 'ok'.
  
  test3() ->
      Self = self(),
      %% spawn(fun() -> foo31 end)
      sched:rep_spawn(
        fun() ->
                spawn(fun() ->
                              link(whereis(sched)),
                              foo31(Self)
                      end)
        end),
      %% spawn(fun() -> foo32 end)
      sched:rep_spawn(
        fun() ->
                spawn(fun() ->
                              link(whereis(sched)),
                              foo32(Self)
                      end)
        end),
      sched:rep_receive(
        fun(Aux) ->
  	      receive
  