20021118-3.c

this is a gcc file, you can download it and learn its usetility, for further detail please look at t

extern void abort (void);
extern void exit (int);

int
foo (int x)
{
  if (x == -2 || -x - 100 >= 0)
    abort ();
  return 0;
}
           
int
main ()
{
  foo (-3);
  foo (-99);
  exit (0);
}