#include <cstdio>

class Thing {
public:
    ~Thing() {
        printf("destroying Thing\n");
    }
};

class Base {
public:
    // without this destructor, Derived is never cleaned up and
    // Thing::~Thing() is never called
    virtual ~Base() {}
};

class Derived : public Base {
public:
    Thing thing;
};

int main(int argc, char **argv) {
    Base *b = new Derived;
    delete b;
}