Explicitly calling a destructor using a pointer to an object

Question

Not to use in any implementation but just for the sake of understanding I am trying to explicitly call a destructor using an object and another * to object.

CODE

#include<iostream>
using namespace std; 

class A{
public :
A(){
    cout<<"\nConstructor called ";
}

~A()
{
    cout<<"\nDestructor called ";
}
};

int main()
{
    A obj,*obj1;
    obj1->~A();
    obj.~A();
    return 0;
}

OUTPUT

Now the problem is that I can't understand why destructor is called three times.
Even if the obj1 is not yet pointing to any object.
Note that I understand that the last two destructor calls are:

1. because I am calling obj.~A();
2. because we go out of the scope of object obj.

I am using DevC++ 5.5.1

Answer 1

Your code only works by a fluke.

int main()
{   
    A obj,*obj1;
    obj1->~A(); // (1) Bad reference that works
    obj.~A();   // (2) Explicit call to destructor
    return 0;
} // (3) obj's destructor is called when obj goes out of scope

Answer 2

obj1->~A();

You dereference the pointer obj1 which has not been initialized. That is undefined behaviour.

In this situation, anything can happen and nothing is guaranteed.