Is using unsigned integer overflow good practice?

Question

I was reading the C Standard the other day, and noticed that unlike signed integer overflow (which is undefined), unsigned integer overflow is well defined. I\'ve seen it us

Answer 1

Since signed numbers on CPUs can be represented in different ways, 99.999% of all current CPUs use twos-complement notation. Since this is the majority of machines out there, it is difficult to find a different behaviour although the compiler might check it (fat chance). The C specs however must account for 100% of the compilers so have not defined its behaviour.

So it would make things more confusion, which is a good reason to avoid it. However, if you have a really good reason (say, performance boost of factor of 3 for critical part of code), then document it well and use it.