mpyc mult3.py example gives result different from expected when M > 3

[danxinnoble]

For instance:
root@c609d1fbbcde:~/source# python mult3.py -M 6
2021-11-24 11:51:28,496 Start MPyC runtime v0.7
2021-11-24 11:51:28,830 All 6 parties connected.
player 0 input: 4000
expected: 64000000000
result: -740248758255576370955515465
2021-11-24 11:51:28,885 Stop MPyC runtime -- elapsed time: 0:00:00.388515

[marsella]

This library overflows silently, and sometimes has unexpected overflows due to intermediate values in the computation (this is more common with division). I see that 64000000000 is 35 bits, maybe it's overflowing a 32-bit integer?