Anyone know what the -Xc option does? Is there an equivalent option for the Gnu compiler? 
The -Xc option used to compile for ISO C with K&R support, I think.
gcc -Wall compiles with ISO support and "lint" and will also tolerate K&R style functions.
doesnt -Wall just turn on ALL warnings?
-R3d
Yes, including problems with K&R == -Wextra