anchor.diff:  bsm_restore(Reg, {atom,start}, Vst) ->
       %% (Mostly) automatic save point refering to where the match started.
       %% It is always valid. But don't forget to validate the context register.
  -    bsm_get_context(Reg, Vst),
  +    bsm_validate_context(Reg, Vst),
       Vst;
   bsm_restore(Reg, SavePoint, Vst) ->
       case bsm_get_context(Reg, Vst) of
  
positive.code: %%
  
  assert_type(WantedType, Term, Vst) ->
      assert_type(WantedType, get_term_type(Term, Vst)),
      Vst.
  
  assert_type(Correct, Correct) -> ok;
  assert_type(float, {float,_}) -> ok;
  
negative.code: bsm_save(Reg, {atom,start}, Vst) ->
      %% Save point refering to where the match started.
      %% It is always valid. But don't forget to validate the context register.
      bsm_validate_context(Reg, Vst),
      Vst;
  bsm_save(Reg, SavePoint, Vst) ->
      case bsm_get_context(Reg, Vst) of
  