g++ doesn't accept this code:

template<int N, int I=N> struct K;

template<int N> struct K<N, 1>
{
	void f();
};

template<int N, int I> struct K : public K<N, I-1>
{
	using K<N, I-1>::f;
	typedef const char A[N*I];
	void f(const A &) const;
};

template<int N> struct Q : public K<N>, public K<N-1>
{
    using K<N>::f;
    using K<N-1>::f; // error: using declaration ‘using K<4, 4>::f’ conflicts with a previous using declaration
};

int main()
{
    Q<5> v;
    char a5x3[15];
    v.f(a5x3);
    char a4x2[8];
    v.f(a4x2);
}