PRC wrote: > --------------------------------- > int main() > { > char a = -7; > > if( a < -9 ) > printf("a"); > else > printf("b"); > } > --------------------------------- > sde-gcc -c a2.c > c:/a2.c: In function `main': > c:/a2.c:6: warning: comparison is always false due to limited range of data type > > It may be the reason for this warning that gcc thinks `char' as 'unsigned char' by default. > Can I change the default configuration by modifying some configuration file? > Or this feature can't be changed after gcc has been built? -fsigned-char The signedness of characters is part of a machine's ABI. If you really need to have unsigned chars, declare them as such. Andrew.