#include <cstddef>
#include <memory>
#include <type_traits>
#include <utility>

#if (!defined(__clang__) && !defined(_MSC_VER) && __GNUC__ == 4 && __GNUC_MINOR__ < 9)

namespace std
{
template <class T> struct _Unique_if
{
  typedef unique_ptr<T> _Single_object;
};

template <class T> struct _Unique_if<T[]>
{
  typedef unique_ptr<T[]> _Unknown_bound;
};

template <class T, size_t N> struct _Unique_if<T[N]>
{
  typedef void _Known_bound;
};

template <class T, class... Args> typename _Unique_if<T>::_Single_object make_unique(Args &&... args)
{
  return unique_ptr<T>(new T(std::forward<Args>(args)...));
}

template <class T> typename _Unique_if<T>::_Unknown_bound make_unique(size_t n)
{
  typedef typename remove_extent<T>::type U;
  return unique_ptr<T>(new U[n]());
}

template <class T, class... Args> typename _Unique_if<T>::_Known_bound make_unique(Args &&...) = delete;
}

#endif

Add alternative implementation of memory.h
Add alternative implementation of memory.h
