How does sizeof work in C++?

Question

Hello,

I read:

The memory space is allocated to the data members of a class only when an object of the class is declared, and not when the data members are declared inside the class.

>

Why does sizeof(Base) 44?

I didn't create an instance of the Base class and expected the compiler doesn't allocate memory for Base.

Please see the following code:

#include <iostream>
using namespace std;

class Base
{
public:
    void Print() {
        cout << "In Base..";
    }
    int a;
    int arr[10];
};


int main() {

    cout << sizeof(Base) << endl; // 44


    return 0;
}

Answer 1

The compiler did not allocate any memory for your class. What it did do is determine how many bytes of storage it would take if such a class was created. I suggest you read sizeof-operator