I have a hunch that you messed something up near the beginning of the file, and the stdarg.h error is simply the compiler complaining as a result of something in your file. For example:
Code:
int foo = 6 // no semicolon!
#include <stdio.h>
will tend to give you an error in stdio.h, even though the problem is in the original file. Take a look at the top of your file for syntax errors.