Calling of delete after construction throwing an exception

Question

I'm reading Effective C++ 3rd Edition, item52 "Write placement delete if you write placement new".

I want to how to make the operator delete automatically called after construction throwing an exception.

#include <iostream>
using namespace std;

class A {
    int i;
public:
    static void* operator new(std::size_t size) throw(std::bad_alloc) {
        return malloc(size);
    }
    static void operator delete(void* p) throw() {
        cout << "delete" << endl;
        free(p);
    }
    A() {
        throw exception();
    }
};

int main() {
    A* a = new A;
}

The above codes only output:

terminate called after throwing an instance of 'std::exception'
  what():  std::exception
[1]    28476 abort      ./test_clion

Answer 1

Reference: operator delete, operator delete[]

I should write new in try {}. Know too little about exceptions for now.

#include <iostream>
using namespace std;

class A {
    int i;
public:
    static void* operator new(std::size_t size) throw(std::bad_alloc) {
        return malloc(size);
    }
    static void operator delete(void* p) throw() {
        cout << "delete" << endl;
        free(p);
    }
    A() {
        throw exception();
    }
};

int main() {
    try {
        A* a = new A;
    } catch (const exception&) {

    }
}

And the output:

delete