用于进行gcc测试

				#ifndef NO_TRAMPOLINES				extern void abort (void);								int x(int a, int b)				{				  __label__ xlab;				  __label__ xlab2;								  void y(int b)				    {				       switch (b)				        {				          case 1: goto xlab;				          case 2: goto xlab;				        }				    }								  a = a + 2;				  y (b);								 xlab:				  return a;								 xlab2:				  a++;				  return a;								}								int main ()				{				  int i, j;								  for (j = 1; j 				    for (i = 1; i 				      {					int a = x (j, i);					if (a != 2 + j)					  abort ();				      }								  return 0;				}				#else				int main() { return 0; }				#endif