gcc-you can use this code to learn something about gcc, and inquire further into linux,

				f (int phaseone)				{				  typedef struct				    {				      unsigned char *p;				    }				  FILE;				  FILE b[2];				  static unsigned char xchr[2];				  int j;				  int for_end;				  if (phaseone)				    {				      if (j 					do					  *(b[1].p) = xchr[j];					while (j++ < 10);				    }				}