ctor_dtor.cpp

#include <iostream>
using namespace std;

struct foo {
  foo() {
    cout << "ctor" << endl;
  }

  ~foo() {
    cout << "dtor" << endl;
  }
};

int main() {
  foo foo_ {};  // "ctor" of foo_; stack allocation
  foo* bar = new foo {}; // "ctor" of bar; heap allocation
  foo* baz = new foo {}; // "ctor" of baz; heap allocation

  new (&foo_) foo {}; // "ctor" of foo_; placement new

  delete(bar); // "dtor" of bar; heap destruction
  ::operator delete(baz); // nothing; heap deallocation

  // "dtor" of foo_; stack destruction
}