{ \
  template<> \
  class deque<__VA_ARGS__, std::allocator<__VA_ARGS__> >           \
    : public deque<__VA_ARGS__, EIGEN_ALIGNED_ALLOCATOR<__VA_ARGS__> > \
  { \
    typedef deque<__VA_ARGS__, EIGEN_ALIGNED_ALLOCATOR<__VA_ARGS__> > deque_base; \
  public: \
    typedef __VA_ARGS__ value_type; \
    typedef deque_base::allocator_type allocator_type; \
    typedef deque_base::size_type size_type;  \
    typedef deque_base::iterator iterator;  \
    explicit deque(const allocator_type& a = allocator_type()) : deque_base(a) {}  \
    template<typename InputIterator> \
    deque(InputIterator first, InputIterator last, const allocator_type& a = allocator_type()) : deque_base(first, last, a) {} \
    deque(const deque& c) : deque_base(c) {}  \
    explicit deque(size_type num, const value_type& val = value_type()) : deque_base(num, val) {} \
    deque(iterator start, iterator end) : deque_base(start, end) {}  \
    deque& operator=(const deque& x) {  \
      deque_base::operator=(x);  \
      return *this;  \
    } \
  }; \
}
This section contains a convenience MACRO which allows an easy specialization of std::deque such that for data types with alignment issues the correct allocator is used automatically.