window = unique_ptr<SDL_Window, decltype(free) *>
    reinterpret_cast<SDL_Window *>(malloc(sizeof(SDL_Window))),
    free};

&window.get()
// or
&&(*window)
// or
&window
// and even
&(&(*(window.get())))

SDL_Window *window_ptr;
unique_ptr<SDL_Window> window;

window = unique_ptr<SDL_Window, decltype(SDL_DestroyWindow)> (
    window_ptr,
    SDL_DestroyWindow);

SDL_CreateWindowAndRenderer(500, 500, SDL_WINDOW_SHOWN, &window_ptr, &renderer_ptr);

/usr/include/c++/5/bits/unique_ptr.h:272:18: error: no match for ‘operator=’
(operand types are ‘std::unique_ptr<SDL_Window>::deleter_type
{aka std::default_delete<SDL_Window>}’ and ‘void (*)(void*)’)
get_deleter() = std::forward<_Ep>(__u.get_deleter());

SDL_Window *window_;
SDL_Renderer *renderer_;
SDL_CreateWindowAndRenderer (/* ... */, &window_, &renderer_);
unique_ptr<SDL_Window, decltype(&SDL_DestroyWindow)>
    window(window_, &SDL_DestroyWindow);

std::unique_ptr<myclass> uptr;

myclass*& inside = *reinterpret_cast<myclass**>(&uptr);

#include <iostream>
#include <memory>

class myclass {
public:
    myclass() {
    }
    ~myclass() {
        std::cout << "It works!n";
    }
};

int main()
{

    std::unique_ptr<myclass> uptr;

    myclass*& inside = *reinterpret_cast<myclass**>(&uptr);

    inside = new myclass();

    return 0;
}