gcc/testsuite/gcc.dg/noncompile/930622-1.c - gcc - Git at Google

 void
 f ()
 {
   double b;
   b = b * 10;
   goto c;	/* { dg-error "used but not defined" } */
 }
	void
	f ()
	{
	double b;
	b = b * 10;
	goto c; /* { dg-error "used but not defined" } */
	}