Re: [PATCH] libstdc++/77641 fix std::variant for literal types

[Jonathan Wakely]

On 22/09/16 09:37 +0100, Jonathan Wakely wrote:

On 22/09/16 09:45 +0300, Ville Voutilainen wrote:

This problem is not introduced by the latest patch, but it's something that
we should look at anyway. There's been recent discussion about what
assignments do with variants that hold references. Consider this:

#include <variant>

int main()
{
 float f1 = 1.0f, f2 = 2.0f;

 std::variant<float&> v1(f1);

 v1 = f2; // #1
}

It works if we add this to _Reference_storage:

    template<typename _Tp>
        _Reference_storage&
        operator=(_Tp&& __t)
        {
          _M_storage = std::forward<_Tp>(__t);
          return *this;
        }

I'm not sure if that's the right fix.

Oh I missed Tim's patch for this that he already posted.