Error storing instance of member function template

Question

I'm trying to store a pointer to an instance of the member function template Derived::initialize as follows (see also rextester.com. For posterity, I've created a simpler version of the problem.):

class Base
{
public:
    typedef void (Base::*setterFunction)( unsigned );

    template<unsigned N>
    struct SetterInterface
    {
        static Base::setterFunction Function;
    };

protected:
    template<unsigned N>
    void setterImpl( unsigned )
    {
    }
};

template<unsigned N>
Base::setterFunction Base::SetterInterface<N>::Function = &Base::setterImpl<N>;

class Derived : public Base
{
public: 
    typedef void (Derived::*Initializer)();

    template<typename T , void (T::*F)( unsigned ) >
    void initialize()
    {
    }

    template<typename C>
    Derived( C* )
    {
        Initializer initializer = &Derived::initialize<C, C::template SetterInterface<0>::Function>;    // NOT OK
        //Initializer initializer = &Derived::initialize<C, C::template setterImpl<0> >;    // OK
    }
};

int main()
{
    Derived derived( (Base*)0 );
}

But I'm getting the error message on GCC 5.4.0 (and 6.4.0)

Test.cpp: In instantiation of ‘Derived::Derived(C*) [with C = Base]’:
Test.cpp:45:28:   required from here
Test.cpp:37:39: error: no matches converting function ‘initialize’ to type ‘Derived::Initializer {aka void (class Derived::*)()}’
   Initializer initializer = &Derived::initialize<C, C::template SetterInterface<0>::Function>;
                                       ^
Test.cpp:30:7: note: candidate is: template<class T, void (T::* F1)(unsigned int)> void Derived::initialize()
  void initialize()

The problem appears to lie with the member function template argument because C::template setterImpl<0> works whereas C::template SetterInterface<0>::Function (which I suppose to be an alias to the former) does not. For example:

Base::setterFunction f1 = &Base::setterImpl<0>;
Base::setterFunction f2 = Base::template SetterInterface<0>::Function;

Answer 1

The problem is that initialize() non-type-template-parameter should be a constant expression; in your code it's a static member instead, so it cannot work; it could, if you declared it as static constexpr ( but you'd need at least a C++11 compiler then ):

class Base
{
protected:
    template<unsigned N>
    void setterImpl( unsigned );
public:
    typedef void (Base::*setterFunction)( unsigned );

    template<unsigned N>
    struct SetterInterface
    {
        static constexpr Base::setterFunction Function = &Base::setterImpl<N>;
    };
};