Performance benefit when using uint_fast8_t?

the "fast" integer types are defined to be the fastest integer type available with at least the amount of bits required (in this case 8).

If your platform defines uint_fast8_t as uint8_t then there will be absolutely no difference in speed.

The reason is that there may be architectures that are slower when not using their native word length. E.g. I could find one reference where for Alpha processors uint_fast_8_t was defined to be "unsigned int".

An uint_fast8_t is the fastest integer guaranteed to be at least 8 bits wide. Depending on your platform it could be 8 or 16 or 32 bits wide.

It isnt taken care of by the compiler itself, it does indeed make your program execute faster

Here are some resource I found, You might already have seen them http://embeddedgurus.com/stack-overflow/2008/06/efficient-c-tips-1-choosing-the-correct-integer-size/

http://www.mail-archive.com/[email protected]/msg03149.html