Trying to detect bad pointers to class members

Im trying to detect if the pointers are bad.

But for some reason the func is always called.

I expected it to return as soon as it found the 1st bad pointer, but it keeps calling each function

template<typename T>
inline bool IsValid(T dwAddress) {
    return (dwAddress && HIWORD(dwAddress) != 0) ? true : false;
}
#define CHECK_BAD_PTR(x) if(!IsValid(x)) return nullptr

class A{
public:
    A() {}
    void func(int i){
        Sleep(10000);
        i += 10;
    }
};

class B{
public:
    B() {}
    inline A* getA() { CHECK_BAD_PTR(this); return a; }
private:
    A* a;
};

class C {
public:
    inline B* getB() { CHECK_BAD_PTR(this); return b; }
private:
    B* b;
};

class D{
public:
    D() {}
    inline C* getC() { CHECK_BAD_PTR(this); return c; }
private:
    C* c;
};


D d;
d.getC()->getB()->getA()->func(10);