Comparision between signed char and unsigned char. Warnings.

How to force compiler qcc (or even gcc) to display warnings about comparisions between [color=green]signed char and [color=green]unsigned char during compilation code in C?

I have some quite large code in C which I didn’t write. I have to check it if there are comparisions between [color=green]signed char and [color=green]unsigned char. Unfortunately, qcc doesn’t show such warings. Compiler gcc shows warnings only for [color=green]signed int and [color=green]unsigned int. I tried option -w9 for qcc and -Wsign-compare for gcc… without result. Is there posibility to find such comparisions in C code?

Of course, replacing all [color=green]signed chars by [color=green]unsigned char or inversely doesn’t come into play.

I’m not aware of such a feature. But you might want to look at pclint (, works wonders.