Underhanded stuff in C++. No warnings from the compiler

SaneCode.cpp

// curtesy of https://github.com/DavidSaxon and http://www.parashift.com/c++-faq-lite/

#include <iostream>

// this function will be called by the base class
void baseFunction() {

    std::cout << "Base Class!" << std::endl;
}

// this function will be called by the derived class
void derivedFunction() {

    std::cout << "Derived Class!" << std::endl;
}

// just a testing function that nothing ever calls
void shouldNeverBeCalled() {

    std::cout << "Nope!" << std::endl;
}

// base class
class Base {
public:

    // constructor
    Base() {

        // point the function variable to the base function
        function = &baseFunction;
    }

    // pointer to a function
    void (*function)();
};

// derived class
class Derived : public Base {
public:

    // constructor
    Derived() {

        // point the function variable to the derived function
        function = &derivedFunction;
        // put the address of the function into this extra variable since it's
        // feeling lonely and wants something to do
        i = (long) function;
    }

    long i;
};

// this calls the function on the second item in the given array
void callFunctionOnArray(Base* base) {

    base[1].function();
}

// main function
int main() {

    std::cout << std::endl;
    std::cout << "-------------------------------------------------------------"
                 "-------------------"
              << std::endl;
    std::cout << std::endl;
    std::cout << "Will the base or derived class function be called?"
              << std::endl;
    std::cout << std::endl;

    // make an array of the derived class
    Derived arrayOfDerived[10];
    // check the elements are definitely of type Derived by attempting to access
    // the extra variable which the derived class has (it doesn't matter that we
    // are messing with it since the first element in the array is never used)
    arrayOfDerived[0].i += 34;
    // should print 'derived function' right?
    callFunctionOnArray(arrayOfDerived);

    std::cout << std::endl;
    std::cout << "-------------------------------------------------------------"
                 "-------------------"
              << std::endl;

    return 0;
}