anchor.diff:      %% Fun is a symbol which is either a known BIF or function.
       Call = fun (Cas, En, Li, Sta) ->
                      Ar = length(Cas),
  +                   Ann = line_file_anno(Li, Sta),
                      case get_fbinding(Fun, Ar, En) of
                          {yes,M,F} ->                %Import
  -                           {c_call(c_atom(M), c_atom(F), Cas, [Li]),Sta};
  +                           {c_call(c_atom(M), c_atom(F), Cas, Ann),Sta};
                          {yes,Name} ->
                              %% Might have been renamed, use real function name.
  -                           Ann = [L,{file,Sta#cg.file}],
                              {c_apply(c_fname(Name, Ar), Cas, Ann),Sta}
                      end
              end,
  
positive.code:     {Cg,St1} = comp_gbody(Ts, Env, L, St0),
      True = comp_lit(true),
      Call = fun (Cas, _, L, St) ->
                     {c_call(c_atom(erlang), c_atom('=:='), Cas, [L]),St}
             end,
      simple_seq([Cg,True], Call, Env, L, St1).
  
  
negative.code:     {Fvs,St3} = new_c_vars(Ar, L, St2),
      Cf = func_fail(Fvs, L, St3),
      Cb = c_case(c_values(Cvs), Ccs ++ [Cf], [L]),
      Ann = line_file_anno(L, St3),
      {c_fun(Cvs, Cb, Ann),St3}.
  
  func_fail(Fvs, L, #cg{func=F}=St) ->
      %% We need function_name anno to generate function_clause error.
  