unsigned interger overflow

[Jonathan M Davis]

On Wednesday, October 02, 2013 12:32:24 Alexandr Druzhinin wrote:
> Is it safe to replace code:
> 
> uint index;
> // do something
> index++;
> if(index == index.max)
> index = index.init;
> 
> by the following code
> uint index;
> // do something
> index++; /// I use unsigned int so uint.max changed to 0 automagically

Well, not quite. Your first one skips uint.max. It goes from uint.max - 1 to 0, 
whereas the second one goes from uint.max to 0. So, they're subtly different. 
But yes, incrementing the maximum value of an unsigned integral type is 
guaranteed to wrap around to 0. Signed integers are of course another matter 
entirely, but it's guaranteed to work with unsigned integers.

- Jonathan M Davis