type __ghdl_bool_type is boolean {false, true};
type __ghdl_integer is signed (32);

public function test_arg (v : __ghdl_bool_type) return __ghdl_integer
declare
begin
  if v then
   return __ghdl_integer'[1];
  else
   return __ghdl_integer'[0];
  end if;
end;