pub unsafe extern "C" fn secp256k1_rangeproof_verify(
    ctx: *const Context,
    min_value: &mut u64,
    max_value: &mut u64,
    commit: *const PedersenCommitment,
    proof: *const c_uchar,
    plen: size_t,
    extra_commit: *const c_uchar,
    extra_commit_len: size_t,
    gen: *const PublicKey
) -> c_int