[Bug libstdc++/49107] [C++0x] incomplete type regression with std::pair

[marc.glisse at normalesup dot org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49107

--- Comment #3 from Marc Glisse <marc.glisse at normalesup dot org> 2011-05-22 
12:12:50 UTC ---
(In reply to comment #1)
> I think since std::pair started using noexcept and therefore is_constructible 
> &
> co. Frankly doesn't look to me like a library-proper issue, I'm adding Daniel
> and Jason in CC... If you could reduce it a bit more, it would be great.

Slightly reduced below. I hope noexcept doesn't have the same issues as the
concept checking mode of the library...


#include <type_traits>

namespace std
{
  template<typename _Tp>
    inline void
    swap(_Tp& __a, _Tp& __b)
    noexcept(is_nothrow_move_constructible<_Tp>::value
             && is_nothrow_move_assignable<_Tp>::value) ;

  template<class _T1, class _T2>
    struct pair
    {
      _T1 first;
      _T2 second;

      void
      swap(pair& __p)
      noexcept(noexcept(swap(first, __p.first))
               && noexcept(swap(second, __p.second))) ;

    };
}

template < class R_ >
struct VectorH3
{
  typedef typename R_::RT                   RT;
  typedef typename R_::Ray_3                Ray_3;
  typedef typename R_::Line_3               Line_3;
  VectorH3() {}
  VectorH3(const Ray_3& r) ;
  VectorH3(const Line_3& l) ;
  VectorH3(const RT& x, const RT& y, const RT& z, const RT& w) ;
};

template < class R_ >
class RayH3
{
   typedef typename R_::Point_3              Point_3;
   typedef typename R_::Vector_3             Vector_3;
   typedef std::pair<Point_3, Vector_3>             Rep;
   Rep base;
};

template < class R_ >
struct LineC3
{
  typedef typename R_::Point_3              Point_3;
  typedef typename R_::Vector_3             Vector_3;
  typedef std::pair<Point_3, Vector_3>             Rep;
  Rep base;
};

struct Kernel
{
    typedef double                                  RT;
    struct Point_3{};
    typedef VectorH3<Kernel>                        Vector_3;
    typedef LineC3<Kernel>                          Line_3;
    typedef RayH3<Kernel>                           Ray_3;
    struct Construct_vector_3
    {
    Vector_3 operator()(const RT& x, const RT& y, const RT& z, const RT& w)
const
    { return Vector_3(x, y, z, w); }
    };
};


int main()
{
  Kernel::Construct_vector_3()( 8, 2, 4, 1);
}