Re: Doubt regarding Virtual Inheritance

ok this is an upgraded prog of the above one

#include <iostream>
using namespace std;

class A
{
public:
    int a;
    A():a(10){}
};
class B:public A
{
public:
    int b;
    B():b(20){}
};
class C:public A
{
public:
    int c;
    C():c(30){}
};
class D:public B, public C
{
public:
    int d;
    D():d(40){}
};

int main()
{
    int size[4];

    size[0] = sizeof(A);
    size[1] = sizeof(B);
    size[2] = sizeof(C);
    size[3] = sizeof(D);

    cout << "Sizeof(A) " << size[0] << endl;
    cout << "Sizeof(B) " << size[1] << endl;
    cout << "Sizeof(C) " << size[2] << endl;
    cout << "Sizeof(D) " << size[3] << endl << endl;

    /*
     * The following operations are done for
     * the sake for anatomy of structure of
     * memory alignment in an object.
     */

    int i = 0;
    int count = 0;
    int *p = NULL;
    cout << "Analysis of object of A" << endl;
    A a;
    p = (int*)&a;
    for(i = 0, count = 0; i < size[0]; i += 4, ++count)
        cout << "*(pa + " << count << ") = " << *(p + count) << endl;
    cout << endl;

    cout << "Analysis of object of B" << endl;
    B b;
    p = (int*)&b;
    for(i = 0, count = 0; i < size[1]; i += 4, ++count)
        cout << "*(p + " << count << ") = " << *(p + count) << endl;
    cout << endl;

    cout << "Analysis of object of C" << endl;
    C c;
    p = (int*)&c;
    for(i = 0, count = 0; i < size[2]; i += 4, ++count)
        cout << "*(p + " << count << ") = " << *(p + count) << endl;
    cout << endl;

    cout << "Analysis of object of D" << endl;
    D d;
    p = (int*)&d;
    for(i = 0, count = 0; i < size[3]; i += 4, ++count)
        cout << "*(p + " << count << ") = " << *(p + count) << endl;
    cout << endl;

    return 0;
}

if you people got time check the program with and without virtual
keyword. You can see virtual pointers are there in action. whats their
role in virtual inheritance even though i didnt declare any virtual
functions?.

I even checked the virtual address table its empty (since no virtual
function). Whats is purpose of a virtual table/pointer in virtual
inheritance even though there is no virtual function?

moderators please pardon for making a huge post...