Function gmp_mpfr_sys::mpfr::custom_init_set

pub unsafe extern "C" fn custom_init_set(
    x: *mut mpfr_t, 
    kind: c_int, 
    exp: exp_t, 
    prec: prec_t, 
    significand: *mut c_void
)

See: mpfr_custom_init_set