(Crossposted to gcc-help and elinks-dev) In ELinks, we're using unsigned char almost everywhere. This convention was apparently inherited from Links. I think the purpose might be to reduce the need for casts in <ctype.h> calls and charset conversions. Then we have functions like void elinks_debug(unsigned char *fmt, ...); that take a format string and arguments. It would be nice to have GCC check that the types of those arguments match the format string. But if I declare the function as void elinks_debug(unsigned char *fmt, ...) __attribute__((format(printf, 1, 2))); then GCC 4.3.1 rejects it, even with -Wno-pointer-sign: /home/Kalle/src/elinks-0.12/src/util/error.h:23: error: format string argument not a string type If I change the unsigned char * to char *, then this error goes away. But is there any other way to make GCC check the format arguments without this error?
