anchor.diff:  %%  The stackframe must be initialized.
   %%  The instruction will return to the instruction following the call.
   call(Name, Live, #vst{current=St}=Vst) ->
  -    verify_live(Live, Vst),
  +    verify_call_args(Name, Live, Vst),
       verify_y_init(Vst),
       case return_type(Name, Vst) of
   	Type when Type =/= exception ->
  
positive.code: %% Tail call.
  %%  The stackframe must have a known size and be initialized.
  %%  Does not return to the instruction following the call.
  tail_call(Name, Live, Vst) ->
      verify_call_args(Name, Live, Vst),
      verify_y_init(Vst),
      verify_no_ct(Vst),
      kill_state(Vst).
  
  verify_call_args(_, 0, #vst{}) ->
      ok;
  verify_call_args({f,Lbl}, Live, Vst) when is_integer(Live)->
      Verify = fun(R) ->
  		     case get_move_term_type(R, Vst) of
  			 #ms{} ->
  			     verify_call_match_context(Lbl, Vst);
  			 _ ->
  			     ok
  		     end
  	     end,
      verify_call_args_1(Live, Verify, Vst);
  verify_call_args(_, Live, Vst) when is_integer(Live)->
      Verify = fun(R) -> get_term_type(R, Vst) end,
      verify_call_args_1(Live, Verify, Vst);
  verify_call_args(_, Live, _) ->
      error({bad_number_of_live_regs,Live}).
  
  verify_call_args_1(0, _, _) -> ok;
  verify_call_args_1(N, Verify, Vst) ->
      X = N - 1,
      Verify({x,X}),
      verify_call_args_1(X, Verify, Vst).
  
  verify_call_match_context(Lbl, #vst{ft=Ft}) ->
      case gb_trees:lookup(Lbl, Ft) of
  	none ->
  	    error(no_bs_start_match2);
  	{value,[{test,bs_start_match2,_,_,[Ctx,_],Ctx}|_]} ->
  	    ok;
  	{value,[{test,bs_start_match2,_,_,[Bin,_,_],Ctx}|_]} ->
  	    error({binary_and_context_regs_different,Bin,Ctx})
      end.
  
  allocate(Zero, Stk, Heap, Live, #vst{current=#st{numy=none}=St}=Vst0) ->
  
negative.code:     merge_bool(A);
  merge_types({atom,A}, bool) ->
      merge_bool(A);
  merge_types(#ms{id=Id,valid=B0,slots=Slots}=M,
  	    #ms{id=Id,valid=B1,slots=Slots}) ->
      M#ms{valid=B0 bor B1,slots=Slots};
  merge_types(#ms{}=M, _) ->
      M;
  