[PATCH] rvalue reference implementation for C++0x

[Russell Yanofsky]

On Wed, 2007-04-25 at 20:06 -0400, Russell Yanofsky wrote:
> >   g++.dg/overload/arg1.C
> >   g++.dg/overload/arg4.C
> 
> These two cases do look like bugs, I'll have to see what causes them.

On second thought, I don't think these are bugs. The problem in both of
these cases is trying to initialize an automatic variable of type B from
a temporary object of type B where B is declared like:

  struct A {};

  struct B : A
  {
    B(int);
    B(B &);
    B(A);
  };

Since B doesn't have a const copy constructor, initializing the variable
directly from the temporary is impossible. But the class A has an
implicit const copy constructor which is allowed to bind to temporary
instances of B under C++0x. Before C++0x, binding to those instances was
not possible because B is uncopyable. But the new rules do not require a
temporary to be copyable to bind a const reference to it. So under the
new rules, these test cases aren't errors.

-- 
-  Russell Yanofsky (PGP ID: 0x5FAA0216)
-  http://russ.yanofsky.org/
--
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