Does the C++ language definition (such as it is) define the result of:

 class C
 {
  C(const C &init) { datum = init.datum; }
  C() { datum = 0; }
  int datum;
 };

 int same_address(C &c1, C &c2)
 {
  return &c1 == &c2;
 }

 main()
 {
  C c;
  cout << same_address(c, C(c));
 }

Is the compiler required to create a distinct copy of c as the second
argument to the function call?  Or could it just give me "c" again?
G++ 2.5.8 and "CC" print 0 for this, but G++ 2.6.1 prints 1.

Thanks for any enlightenment on this,
     Dave Wonnacott
     davew@cs.umd.edu