Segmentation Fault Core dumped

fn get_codewords(owned padded: List[Int]) -> List[Int]:
    var ecwords = List[Int](0)*64
    var values = List[Int]()

    for i in range(222):
        var temp: Int = (padded[i] + ecwords[0]) % 929
        for j in range(63, -1, -1):
            var val: Int = temp * EC_LV5[j] % 929
            var factor: Int = ecwords[64-j] if j > 0 else 0
            ecwords[63-j] = (factor + 929 - val) % 929

    return ecwords