[barrkel]

I care less about C's specific behaviour on shifting and overflow (both of which are pretty rare), and more about the fact that unsigned integers use a different arithmetic to the signed integers most people are familiar with. In particular, subtraction doesn't mean what you think it does. At 0 in unsigned arithmetic, there's a gaping cliff you can fall off of where you wrap around the other side, while at 0 in signed arithmetic, you're well away from that cliff and are highly unlikely to get anywhere near to it. Writing a program using many unsigned numbers means playing on the edge of a cliff.