Question

There is this code:

#include <iostream>

class Base {
public:
    Base(){
        std::cout << "Constructor base" << std::endl;
    }
    ~Base(){
        std::cout << "Destructor base" << std::endl;
    }
    Base& operator=(const Base& a){
        std::cout << "Assignment base" << std::endl;
    }
};

class Derived : public Base{
public:

};

int main ( int argc, char **argv ) {
    Derived p;
    Derived p2;
    p2 = p;
    return 0;
}

The output after compilation by g++ 4.6:

Constructor base
Constructor base
Assignment base
Destructor base
Destructor base

Why assignment operator of base class is called altough it is said that assignment operator is not inherited?

Answer 1

You don’t have a default

Derived& operator=(const Base& a);

in your Derived class.

A default assignment operator, however, is created:

Derived& operator=(const Derived& a);

and this calls the assignment operator from Base. So it’s not a matter of inheriting the assignment operator, but calling it via the default generated operator in your derived class.