[Bug c++/53733] New: [C++11][DR 1402] Move constructor/assignment operator too often deleted

[daniel.kruegler at googlemail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53733

             Bug #: 53733
           Summary: [C++11][DR 1402] Move constructor/assignment operator
                    too often deleted
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: daniel.krueg...@googlemail.com
                CC: ja...@redhat.com, paolo.carl...@oracle.com


This is a place-holder entry as a reminder to fix

http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1402

The following example should be well-formed when compiled in C++11 mode, but is
currently not (tested with gcc 4.8.0 20120610 (experimental)):

template<typename T>
struct wrap
{
  wrap() = default;
  wrap(wrap&&) = default; // Line 5
  wrap(const wrap&) = default;

  T t;
};

struct S {
  S() = default;
  S(const S&){}
  S(S&&) = default;
};

typedef wrap<const S> W;

W get() { return W(); } // Line 19

int main() {}

"In function 'W get()':|
19|error: use of deleted function 'wrap<T>::wrap(wrap<T>&&) [with T = const
S]'|
5|note: 'wrap<T>::wrap(wrap<T>&&) [with T = const S]' is implicitly deleted
because the default definition would be ill-formed:|
5|error: non-static data member 'wrap<const S>::t' does not have a move
constructor or trivial copy constructor|"