In the following code (original is taken from cafe),
static_cast<my_class*>(p)->foo_1 is unresolved;
but on the next line reference to foo_1 is resolved OK

#define NULL 0

template<int> class my_class {};

template<> class my_class<1> {
public:
    void foo_1(void* p) {
        static_cast<my_class*>(p)->foo_1(NULL); // foo_1() is unresolved
        my_class* p2 = static_cast<my_class*>(p);
        p2->foo_1(NULL); // resolved ok
    }
};

template<> class my_class<2> {
public:
    void foo_2(void* p) {
        static_cast<my_class*>(p)->foo_2(NULL); // foo_2() is unresolved
        my_class* p2 = static_cast<my_class*>(p);
        p2->foo_2(NULL); // resolved ok
    }
};