objective c++ operator delete

Question

I have the following code in Xcode command line app:

#import <Foundation/Foundation.h>

#include <string>
#include <vector>
#include <iostream>

using namespace std;

int main(int argc, const char * argv[])
{
    vector<string> *pv = new vector<string>;
    vector<string> &v = *pv;


    v.push_back("juy");
    v.push_back("zxc");

    cout << v[0] << endl << v[1] << endl;

    delete pv;

    cout << v[0] << endl << v[1] << endl;

    cout << pv->operator[](0) << endl << pv->operator[](1) << endl;
    return 0;
}

When I run it, this is the output:

 juy zxc juy zxc juy zxc 

The question is: does operator delete work in objective-c++? Does it cause memory leak?

There are no errors, no exceptions, nor warnings!

Answer 1

Your code has no memory leaks. However, it has undefined behaviour on the following two lines that come after the delete :

cout << v[0] << endl << v[1] << endl;

cout << pv->operator[](0) << endl << pv->operator[](1) << endl;

In other words, after you delete pv , you are not allowed dereference pv . If your program doesn't crash when you do, and if the memory still contains the old data, that means nothing. The behaviour is still undefined.