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#include <cassert>
 
#include <cstddef>
 
#include <functional>
 
#include <new>
 
#include <unordered_map>
 
#include <utility>
 
template <std::size_t N>
class stack_store
{
public:
  stack_store() = default;
 
  stack_store(stack_store const&) = delete;
 
  stack_store& operator=(stack_store const&) = delete;
 
  char* allocate(std::size_t n)
  {
    assert(pointer_in_buffer(ptr_) &&
      "stack_allocator has outlived stack_store");
 
    n = align(n);
 
    if (buf_ + N >= ptr_ + n)
    {
      auto r(ptr_);
 
      ptr_ += n;
 
      return r;
    }
    else
    {
      return static_cast<char*>(::operator new(n));
    }
  }
 
  void deallocate(char* const p, std::size_t n) noexcept
  {
    assert(pointer_in_buffer(ptr_) &&
      "stack_allocator has outlived stack_store");
 
    if (pointer_in_buffer(p))
    {
      n = align(n);
 
      if (p + n == ptr_)
      {
        ptr_ = p;
      }
      // else do nothing
    }
    else
    {
      ::operator delete(p);
    }
  }
 
  void reset() noexcept { ptr_ = buf_; }
 
  static constexpr ::std::size_t size() noexcept { return N; }
 
  ::std::size_t used() const { return ::std::size_t(ptr_ - buf_); }
 
private:
  static constexpr ::std::size_t align(::std::size_t const n) noexcept
  {
    return (n + (alignment - 1)) & -alignment;
  }
 
  bool pointer_in_buffer(char* const p) noexcept
  {
    return (buf_ <= p) && (p <= buf_ + N);
  }
 
private:
  static constexpr auto const alignment = alignof(::max_align_t);
 
  char* ptr_{buf_};
 
  alignas(::max_align_t) char buf_[N];
};
 
template <class T, std::size_t N>
class stack_allocator
{
public:
  using store_type = stack_store<N>;
 
  using size_type = ::std::size_t;
 
  using difference_type = ::std::ptrdiff_t;
 
  using pointer = T*;
  using const_pointer = T const*;
 
  using reference = T&;
  using const_reference = T const&;
 
  using value_type = T;
 
  template <class U> struct rebind { using other = stack_allocator<U, N>; };
 
  stack_allocator() = default;
 
  stack_allocator(stack_store<N>& s) noexcept : store_(&s) { }
 
  template <class U>
  stack_allocator(stack_allocator<U, N> const& other) noexcept :
    store_(other.store_)
  {
  }
 
  stack_allocator& operator=(stack_allocator const&) = delete;
 
  T* allocate(::std::size_t const n)
  {
    return static_cast<T*>(static_cast<void*>(
      store_->allocate(n * sizeof(T))));
  }
 
  void deallocate(T* const p, ::std::size_t const n) noexcept
  {
    store_->deallocate(static_cast<char*>(static_cast<void*>(p)),
      n * sizeof(T));
  }
 
/*
  template <class U, class ...A>
  void construct(U* const p, A&& ...args)
  {
    new (p) U(::std::forward<A>(args)...);
  }
 
  template <class U>
  void destroy(U* const p)
  {
    p->~U();
  }
*/
 
  template <class U, std::size_t M>
  inline bool operator==(stack_allocator<U, M> const& rhs) const noexcept
  {
    return store_ == rhs.store_;
  }
 
  template <class U, std::size_t M>
  inline bool operator!=(stack_allocator<U, M> const& rhs) const noexcept
  {
    return !(*this == rhs);
  }
 
private:
  template <class U, std::size_t M> friend class stack_allocator;
 
  store_type* store_{};
};
 
namespace std
{
  // string
  template<class CharT> class char_traits;
 
  template<class CharT, class Traits, class Allocator> class basic_string;
 
  // unordered_map
  template<class Key, class T, class Hash, class Pred, class Alloc>
    class unordered_map;
 
  // vector
  template <class T, class Alloc> class vector;
}
 
using stack_string = ::std::basic_string<char, ::std::char_traits<char>,
  stack_allocator<char, 128> >;
 
template <class Key, class T, class Hash = ::std::hash<Key>,
  class Pred = ::std::equal_to<Key> >
using stack_unordered_map = ::std::unordered_map<Key, T, Hash, Pred,
  stack_allocator<::std::pair<Key const, T>, 256> >;
 
template <typename T>
using stack_vector = ::std::vector<T, stack_allocator<T, 256> >;
 
int main()
{
  stack_unordered_map<int, int>::allocator_type::store_type s;
  stack_unordered_map<int, int> u(10, stack_unordered_map<int, int>::hasher(),
    stack_unordered_map<int, int>::key_equal(), s);
  return 0;
}

In file included from /usr/include/c++/4.8/unordered_map:47:0,
                 from prog.cpp:10:
/usr/include/c++/4.8/bits/hashtable.h: In instantiation of ‘void std::_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash, _RehashPolicy, _Traits>::_M_deallocate_node(std::_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash, _RehashPolicy, _Traits>::__node_type*) [with _Key = int; _Value = std::pair<const int, int>; _Alloc = stack_allocator<std::pair<const int, int>, 256u>; _ExtractKey = std::__detail::_Select1st; _Equal = std::equal_to<int>; _H1 = std::hash<int>; _H2 = std::__detail::_Mod_range_hashing; _Hash = std::__detail::_Default_ranged_hash; _RehashPolicy = std::__detail::_Prime_rehash_policy; _Traits = std::__detail::_Hashtable_traits<false, false, true>; std::_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash, _RehashPolicy, _Traits>::__node_type = std::__detail::_Hash_node<std::pair<const int, int>, false>]’:
/usr/include/c++/4.8/bits/hashtable.h:763:28:   required from ‘void std::_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash, _RehashPolicy, _Traits>::_M_deallocate_nodes(std::_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash, _RehashPolicy, _Traits>::__node_type*) [with _Key = int; _Value = std::pair<const int, int>; _Alloc = stack_allocator<std::pair<const int, int>, 256u>; _ExtractKey = std::__detail::_Select1st; _Equal = std::equal_to<int>; _H1 = std::hash<int>; _H2 = std::__detail::_Mod_range_hashing; _Hash = std::__detail::_Default_ranged_hash; _RehashPolicy = std::__detail::_Prime_rehash_policy; _Traits = std::__detail::_Hashtable_traits<false, false, true>; std::_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash, _RehashPolicy, _Traits>::__node_type = std::__detail::_Hash_node<std::pair<const int, int>, false>]’
/usr/include/c++/4.8/bits/hashtable.h:1641:37:   required from ‘void std::_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash, _RehashPolicy, _Traits>::clear() [with _Key = int; _Value = std::pair<const int, int>; _Alloc = stack_allocator<std::pair<const int, int>, 256u>; _ExtractKey = std::__detail::_Select1st; _Equal = std::equal_to<int>; _H1 = std::hash<int>; _H2 = std::__detail::_Mod_range_hashing; _Hash = std::__detail::_Default_ranged_hash; _RehashPolicy = std::__detail::_Prime_rehash_policy; _Traits = std::__detail::_Hashtable_traits<false, false, true>]’
/usr/include/c++/4.8/bits/hashtable.h:958:13:   required from ‘std::_Hashtable<_Key, _Value, _Alloc, _ExtractKey, _Equal, _H1, _H2, _Hash, _RehashPolicy, _Traits>::~_Hashtable() [with _Key = int; _Value = std::pair<const int, int>; _Alloc = stack_allocator<std::pair<const int, int>, 256u>; _ExtractKey = std::__detail::_Select1st; _Equal = std::equal_to<int>; _H1 = std::hash<int>; _H2 = std::__detail::_Mod_range_hashing; _Hash = std::__detail::_Default_ranged_hash; _RehashPolicy = std::__detail::_Prime_rehash_policy; _Traits = std::__detail::_Hashtable_traits<false, false, true>]’
/usr/include/c++/4.8/bits/unordered_map.h:97:11:   required from here
/usr/include/c++/4.8/bits/hashtable.h:746:7: error: ‘std::_Hashtable<int, std::pair<const int, int>, stack_allocator<std::pair<const int, int>, 256u>, std::__detail::_Select1st, std::equal_to<int>, std::hash<int>, std::__detail::_Mod_range_hashing, std::__detail::_Default_ranged_hash, std::__detail::_Prime_rehash_policy, std::__detail::_Hashtable_traits<false, false, true> >::_Node_allocator_type’ has no member named ‘destroy’
       _M_node_allocator().destroy(__n);
       ^

Standard output is empty