You can often override that to be 8-bit on compilers for 8-bit microcontrollers, on which C's integer promotion rules to 16 bits can be costly. I'd think that w

You can often override that to be 8-bit on compilers for 8-bit microcontrollers, on which C's integer promotion rules to 16 bits can be costly. I'd think that while a good compiler should be able to optimise those away, even a good programmer might not always write code that provides the compiler with the hints to do that.