typedef struct
{
    signed int si01 : 2;   //遵循1
    signed int si02 : 2;
  unsigned int serv : 28;
} sData;

int main ( void )
{
  sData my_data;

  my_data.si01 = -1;
  my_data.si02 = -1;

  return ( 0 );
}