Bob Blick wrote:

> I'm using HiTech C on a 16F688 and notice a promotion I didn't think
> should happen. Here's a little example. "Something" is unimportant
> but included for context.
> 
> unsigned char foo;
> unsigned char bar;
> unsigned char bat;
> 
> if(bat==foo+bar)
>     Something();

As others have said. Applying the "as if" rule to your code, what you
may want could be

if( bat == (unsigned char)(foo+bar) )
    Something();

Whether or not you want this depends mainly on what you want the
comparison to do when (foo+bar) overflows from unsigned char into int
land: do you want 1 == (255+2) to be true (the cast is needed) or false
(the cast is wrong, and the original code does exactly what you want it
to do)?

Gerhard
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