SPL_X
# define SPL_X(x) do { } while (0)
# undef SPL_X
# define SPL_X(x) splx(x)
# define SPL_X(x) ;
# define SPL_X(x) (void) splx(x)
# undef SPL_X
# define SPL_X(x) ;
# undef SPL_X
# define SPL_X(x) ;
# define SPL_X(x) (void) splx(x)
# undef SPL_X
# define SPL_X(x) ;
# define SPL_X(x) ;