C++ stubbing via --wrap

stubbing.cpp

//_ZN1X1fEv
struct stubs
{
    typedef void(stubs::*_ZN1X1fEv_t)();
    static _ZN1X1fEv_t _ZN1X1fEv_p;

    template<typename T, typename ... Args>
    static void   set__ZN1X1fEv(void (T::*p)(Args...))
    {
        _ZN1X1fEv_p = reinterpret_cast<_ZN1X1fEv_t>(p);
    }
    static void reset__ZN1X1fEv() { _ZN1X1fEv_p = _ZN1X1fEv_t(0);}

    void real__ZN1X1fEv() asm("__real__ZN1X1fEv");
    void wrap__ZN1X1fEv() asm("__wrap__ZN1X1fEv");

};

stubs::_ZN1X1fEv_t stubs::_ZN1X1fEv_p = 0;
void stubs::wrap__ZN1X1fEv()
{
   if (_ZN1X1fEv_p)
        (this->*_ZN1X1fEv_p)();
    else
        (this->real__ZN1X1fEv)();
}