pub unsafe extern "C" fn _fmpz_mod_poly_gcd_euclidean(
    G: *mut fmpz,
    A: *const fmpz,
    lenA: mp_limb_signed_t,
    B: *const fmpz,
    lenB: mp_limb_signed_t,
    invB: *const fmpz,
    p: *const fmpz
) -> mp_limb_signed_t