* Yaron Minsky:

> That's a problem too, but there is at least a defensible reason for
> that, which is that it is expensive to get integer overflow to throw
> an exception.

i386 and amd64 have hardware support for that, so it's not very
expensive.  There are pretty short RISC sequences for the checks, too.

MLton uses the i386 hardware support, and I think you can disable the
checks, so measuring the overhead shouldn't be too hard.