Function gmp_mpfr_sys::mpfr::can_round

pub unsafe extern "C" fn can_round(
    b: *const mpfr_t, 
    err: exp_t, 
    rnd1: rnd_t, 
    rnd2: rnd_t, 
    prec: prec_t
) -> c_int

See: mpfr_can_round