a problem in use an overrided void in a object

Hi,

Have a look at this piece of code:

A aObj;
aObj = C();
aObj.foo();

aObj is, even because you call C(); and not A();, an instance of A. And in A, the method foo is empty. I did this test:

#include <iostream>
using namespace std;
 
class A;
 
class A {
public:
    virtual void foo() { }
};
 
class C : public A {
public:
    virtual void foo() { cout << "abc?" << endl; }
    int i;
};
 
int main()
{
 
    A aObj;
    aObj = C();
    aObj.i = 0;
    aObj.foo();
}

I got a compiler error 'class A' has no member named 'i' So, I'm sure aObj is an instance of A You can try

C aObj;
aObj = C();
aObj.foo();

instead of:

A aObj;
aObj = C();
aObj.foo();

Hope this helps.