ncc map::emplace issue

main.cpp

#include <map>

class A
{
public:
    A(int a) {}
    A(const A &a) = delete;
    // A(A&& a) = default;
};

int main()
{
    std::map<int, A> m;

    m.emplace(std::piecewise_construct, std::forward_as_tuple(1),
              std::forward_as_tuple(2));
}