// InterViews (ibuild) requires this to work.extern "C" void exit(int);void *old;class c1{  int i;public:  c1 () {}};class c2{  int j;public:  c2 () {}};class c3 : public c1, public c2{public:  c3 ()    {      old = this;      // printf("new object c3 at %x\n", (int)this); }    }};c2* f (){  c2* n = new c3 ();  // printf ("new object c3 casted to c2 at %x\n", (int)n);  return n;}int main (){  c3* o = (c3*)f ();  // printf("new object c3, upcasted from c2 at %x\n", (int)o);  // if old and o are not the same, fail the test case.  if (old != o)    exit(1);  return 0;}