1extern void abort (void); 2extern void foo (void); 3extern void *bar (void); 4 5typedef void (*func_p) (void); 6 7extern const func_p p1; 8 9func_p p2 = &foo; 10func_p p3 = &foo; 11 12int 13main () 14{ 15 void *p = bar (); 16 p1 (); 17 p2 (); 18 p3 (); 19 if (p != p1) 20 abort (); 21 return 0; 22} 23