#include <iostream>
#include <cstddef>
 
struct Containing {
    struct {
        void* get_containing () {
            return this;
        }
    } inner;
};
 
 
int main () {
    Containing c;
    std::cout << (c.inner.get_containing() == &c ? "success" : "fail") << std::endl;
    std::cout << ((void*)&c.inner == (void*)&c ? "success" : "fail") << std::endl;
    std::cout << ((void*)&c.inner == c.inner.get_containing() ? "success" : "fail") << std::endl;
}

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