[libcxx] Remove <ext/hash_set>, <ext/hash_map> and <ext/__hash>

[ldionne]

Summary

Those headers have been deprecated for a long time and it's about time
we get rid of them. Users should move to std::unordered_set and
std::unordered_map.

[ldionne]

I did run a build of a significant code base with those removed and didn't find any problem. If it breaks some users, I don't think it's going to break many of them.

[mclow.lists]

Oh, I agree. However, when I have proposed this in the past, I have gotten pushback from many people (including Apple, Google and others).
At the very least, you should announce this on llvm-dev, and get feedback there.

[dexonsmith]

In D57688#1383598, @mclow.lists wrote:

Oh, I agree. However, when I have proposed this in the past, I have gotten pushback from many people (including Apple, Google and others).
At the very least, you should announce this on llvm-dev, and get feedback there.

Do you mean libcxx-dev? cfe-dev? (this seems really off topic for llvm-dev)

[mclow.lists]

In D57688#1383617, @dexonsmith wrote:

In D57688#1383598, @mclow.lists wrote:

Oh, I agree. However, when I have proposed this in the past, I have gotten pushback from many people (including Apple, Google and others).
At the very least, you should announce this on llvm-dev, and get feedback there.

Do you mean libcxx-dev? cfe-dev? (this seems really off topic for llvm-dev)

No, l really mean llvm-dev, because that will get a wide audience of libc++ users (not just libc++ developers).

[ldionne]

In D57688#1383618, @mclow.lists wrote:

In D57688#1383617, @dexonsmith wrote:

In D57688#1383598, @mclow.lists wrote:

Oh, I agree. However, when I have proposed this in the past, I have gotten pushback from many people (including Apple, Google and others).
At the very least, you should announce this on llvm-dev, and get feedback there.

Do you mean libcxx-dev? cfe-dev? (this seems really off topic for llvm-dev)

No, l really mean llvm-dev, because that will get a wide audience of libc++ users (not just libc++ developers).

libcxx-dev: http://lists.llvm.org/pipermail/libcxx-dev/2019-February/000191.html

I CC'd llvm-dev to grab their attention.

Louis

[ldionne]

I might revisit this later, but I'm not moving forward for the time being since a bunch of people said it was going to break them.

I think we should instead ship those headers as a separate project and people who need them can still get the headers from that project. IOW, they shouldn't be part of libcxx. But I don't have any time to work on this low priority cleanup at the moment, so abandoning.

[dexonsmith]

In D57688#2833512, @ldionne wrote:

I might revisit this later, but I'm not moving forward for the time being since a bunch of people said it was going to break them.

I think we should instead ship those headers as a separate project and people who need them can still get the headers from that project. IOW, they shouldn't be part of libcxx. But I don't have any time to work on this low priority cleanup at the moment, so abandoning.

Another option to consider, if/when this is revisited, is leaving them in libcxx but shipping them only as a (maybe off-by-default?) cmake configuration option.

libcxx/docs/ReleaseNotes.rst

 What's New in Libc++ 9.0.0?
 ===========================
 
 New Features
 ------------
 
 API Changes
 -----------
-- ...
+- The headers ``<ext/hash_set>``, ``<ext/hash_map>`` and ``<ext/__hash>``
+  have been removed. Those headers have been deprecated for a long time and
+  they are completely removed in this release of libc++. Users should use
+  ``std::unordered_map`` and ``std::unordered_set`` instead.

libcxx/include/CMakeLists.txt

set(files
   experimental/string_view
   experimental/system_error
   experimental/tuple
   experimental/type_traits
   experimental/unordered_map
   experimental/unordered_set
   experimental/utility
   experimental/vector
-  ext/__hash
-  ext/hash_map
-  ext/hash_set
   filesystem
   float.h
   forward_list
   fstream
   functional
   future
   initializer_list
   inttypes.h

libcxx/include/ext/__hash

-// -*- C++ -*-
-//===------------------------- hash_set ------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef _LIBCPP_EXT_HASH
-#define _LIBCPP_EXT_HASH
-
-#pragma GCC system_header
-
-#include <string>
-#include <cstring>
-
-namespace __gnu_cxx {
-using namespace std;
-
-template <typename _Tp> struct _LIBCPP_TEMPLATE_VIS hash { };
-
-template <> struct _LIBCPP_TEMPLATE_VIS hash<const char*>
-    : public unary_function<const char*, size_t>
-{
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(const char *__c) const _NOEXCEPT
-    {
-        return __do_string_hash(__c, __c + strlen(__c));
-    }
-};
-
-template <> struct _LIBCPP_TEMPLATE_VIS hash<char *>
-    : public unary_function<char*, size_t>
-{
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(char *__c) const _NOEXCEPT
-    {
-        return __do_string_hash<const char *>(__c, __c + strlen(__c));
-    }
-};
-
-template <> struct _LIBCPP_TEMPLATE_VIS hash<char>
-    : public unary_function<char, size_t>
-{
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(char __c) const _NOEXCEPT
-    {
-        return __c;
-    }
-};
-
-template <> struct _LIBCPP_TEMPLATE_VIS hash<signed char>
-    : public unary_function<signed char, size_t>
-{
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(signed char __c) const _NOEXCEPT
-    {
-        return __c;
-    }
-};
-
-template <> struct _LIBCPP_TEMPLATE_VIS hash<unsigned char>
-    : public unary_function<unsigned char, size_t>
-{
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(unsigned char __c) const _NOEXCEPT
-    {
-        return __c;
-    }
-};
-
-template <> struct _LIBCPP_TEMPLATE_VIS hash<short>
-    : public unary_function<short, size_t>
-{
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(short __c) const _NOEXCEPT
-    {
-        return __c;
-    }
-};
-
-template <> struct _LIBCPP_TEMPLATE_VIS hash<unsigned short>
-    : public unary_function<unsigned short, size_t>
-{
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(unsigned short __c) const _NOEXCEPT
-    {
-        return __c;
-    }
-};
-
-template <> struct _LIBCPP_TEMPLATE_VIS hash<int>
-    : public unary_function<int, size_t>
-{
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(int __c) const _NOEXCEPT
-    {
-        return __c;
-    }
-};
-
-template <> struct _LIBCPP_TEMPLATE_VIS hash<unsigned int>
-    : public unary_function<unsigned int, size_t>
-{
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(unsigned int __c) const _NOEXCEPT
-    {
-        return __c;
-    }
-};
-
-template <> struct _LIBCPP_TEMPLATE_VIS hash<long>
-    : public unary_function<long, size_t>
-{
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(long __c) const _NOEXCEPT
-    {
-        return __c;
-    }
-};
-
-template <> struct _LIBCPP_TEMPLATE_VIS hash<unsigned long>
-    : public unary_function<unsigned long, size_t>
-{
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(unsigned long __c) const _NOEXCEPT
-    {
-        return __c;
-    }
-};
-}
-
-#endif  // _LIBCPP_EXT_HASH

libcxx/include/ext/hash_map

-// -*- C++ -*-
-//===-------------------------- hash_map ----------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef _LIBCPP_HASH_MAP
-#define _LIBCPP_HASH_MAP
-
-/*
-
-    hash_map synopsis
-
-namespace __gnu_cxx
-{
-
-template <class Key, class T, class Hash = hash<Key>, class Pred = equal_to<Key>,
-          class Alloc = allocator<pair<const Key, T>>>
-class hash_map
-{
-public:
-    // types
-    typedef Key                                                        key_type;
-    typedef T                                                          mapped_type;
-    typedef Hash                                                       hasher;
-    typedef Pred                                                       key_equal;
-    typedef Alloc                                                      allocator_type;
-    typedef pair<const key_type, mapped_type>                          value_type;
-    typedef value_type&                                                reference;
-    typedef const value_type&                                          const_reference;
-    typedef typename allocator_traits<allocator_type>::pointer         pointer;
-    typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
-    typedef typename allocator_traits<allocator_type>::size_type       size_type;
-    typedef typename allocator_traits<allocator_type>::difference_type difference_type;
-
-    typedef /unspecified/ iterator;
-    typedef /unspecified/ const_iterator;
-
-    explicit hash_map(size_type n = 193, const hasher& hf = hasher(),
-                           const key_equal& eql = key_equal(),
-                           const allocator_type& a = allocator_type());
-    template <class InputIterator>
-        hash_map(InputIterator f, InputIterator l,
-                      size_type n = 193, const hasher& hf = hasher(),
-                      const key_equal& eql = key_equal(),
-                      const allocator_type& a = allocator_type());
-    hash_map(const hash_map&);
-    ~hash_map();
-    hash_map& operator=(const hash_map&);
-
-    allocator_type get_allocator() const;
-
-    bool      empty() const;
-    size_type size() const;
-    size_type max_size() const;
-
-    iterator       begin();
-    iterator       end();
-    const_iterator begin()  const;
-    const_iterator end()    const;
-
-    pair<iterator, bool> insert(const value_type& obj);
-    template <class InputIterator>
-        void insert(InputIterator first, InputIterator last);
-
-    void erase(const_iterator position);
-    size_type erase(const key_type& k);
-    void erase(const_iterator first, const_iterator last);
-    void clear();
-
-    void swap(hash_map&);
-
-    hasher hash_funct() const;
-    key_equal key_eq() const;
-
-    iterator       find(const key_type& k);
-    const_iterator find(const key_type& k) const;
-    size_type count(const key_type& k) const;
-    pair<iterator, iterator>             equal_range(const key_type& k);
-    pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
-
-    mapped_type& operator[](const key_type& k);
-
-    size_type bucket_count() const;
-    size_type max_bucket_count() const;
-
-    size_type elems_in_bucket(size_type n) const;
-
-    void resize(size_type n);
-};
-
-template <class Key, class T, class Hash, class Pred, class Alloc>
-    void swap(hash_map<Key, T, Hash, Pred, Alloc>& x,
-              hash_map<Key, T, Hash, Pred, Alloc>& y);
-
-template <class Key, class T, class Hash, class Pred, class Alloc>
-    bool
-    operator==(const hash_map<Key, T, Hash, Pred, Alloc>& x,
-               const hash_map<Key, T, Hash, Pred, Alloc>& y);
-
-template <class Key, class T, class Hash, class Pred, class Alloc>
-    bool
-    operator!=(const hash_map<Key, T, Hash, Pred, Alloc>& x,
-               const hash_map<Key, T, Hash, Pred, Alloc>& y);
-
-template <class Key, class T, class Hash = hash<Key>, class Pred = equal_to<Key>,
-          class Alloc = allocator<pair<const Key, T>>>
-class hash_multimap
-{
-public:
-    // types
-    typedef Key                                                        key_type;
-    typedef T                                                          mapped_type;
-    typedef Hash                                                       hasher;
-    typedef Pred                                                       key_equal;
-    typedef Alloc                                                      allocator_type;
-    typedef pair<const key_type, mapped_type>                          value_type;
-    typedef value_type&                                                reference;
-    typedef const value_type&                                          const_reference;
-    typedef typename allocator_traits<allocator_type>::pointer         pointer;
-    typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
-    typedef typename allocator_traits<allocator_type>::size_type       size_type;
-    typedef typename allocator_traits<allocator_type>::difference_type difference_type;
-
-    typedef /unspecified/ iterator;
-    typedef /unspecified/ const_iterator;
-
-    explicit hash_multimap(size_type n = 193, const hasher& hf = hasher(),
-                           const key_equal& eql = key_equal(),
-                           const allocator_type& a = allocator_type());
-    template <class InputIterator>
-        hash_multimap(InputIterator f, InputIterator l,
-                      size_type n = 193, const hasher& hf = hasher(),
-                      const key_equal& eql = key_equal(),
-                      const allocator_type& a = allocator_type());
-    explicit hash_multimap(const allocator_type&);
-    hash_multimap(const hash_multimap&);
-    ~hash_multimap();
-    hash_multimap& operator=(const hash_multimap&);
-
-    allocator_type get_allocator() const;
-
-    bool      empty() const;
-    size_type size() const;
-    size_type max_size() const;
-
-    iterator       begin();
-    iterator       end();
-    const_iterator begin()  const;
-    const_iterator end()    const;
-
-    iterator insert(const value_type& obj);
-    template <class InputIterator>
-        void insert(InputIterator first, InputIterator last);
-
-    void erase(const_iterator position);
-    size_type erase(const key_type& k);
-    void erase(const_iterator first, const_iterator last);
-    void clear();
-
-    void swap(hash_multimap&);
-
-    hasher hash_funct() const;
-    key_equal key_eq() const;
-
-    iterator       find(const key_type& k);
-    const_iterator find(const key_type& k) const;
-    size_type count(const key_type& k) const;
-    pair<iterator, iterator>             equal_range(const key_type& k);
-    pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
-
-    size_type bucket_count() const;
-    size_type max_bucket_count() const;
-
-    size_type elems_in_bucket(size_type n) const;
-
-    void resize(size_type n);
-};
-
-template <class Key, class T, class Hash, class Pred, class Alloc>
-    void swap(hash_multimap<Key, T, Hash, Pred, Alloc>& x,
-              hash_multimap<Key, T, Hash, Pred, Alloc>& y);
-
-template <class Key, class T, class Hash, class Pred, class Alloc>
-    bool
-    operator==(const hash_multimap<Key, T, Hash, Pred, Alloc>& x,
-               const hash_multimap<Key, T, Hash, Pred, Alloc>& y);
-
-template <class Key, class T, class Hash, class Pred, class Alloc>
-    bool
-    operator!=(const hash_multimap<Key, T, Hash, Pred, Alloc>& x,
-               const hash_multimap<Key, T, Hash, Pred, Alloc>& y);
-
-}  // __gnu_cxx
-
-*/
-
-#include <__config>
-#include <__hash_table>
-#include <functional>
-#include <stdexcept>
-#include <type_traits>
-#include <ext/__hash>
-
-#if __DEPRECATED
-#if defined(_LIBCPP_WARNING)
-    _LIBCPP_WARNING("Use of the header <ext/hash_map> is deprecated.  Migrate to <unordered_map>")
-#else
-#   warning Use of the header <ext/hash_map> is deprecated.  Migrate to <unordered_map>
-#endif
-#endif
-
-#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
-#pragma GCC system_header
-#endif
-
-namespace __gnu_cxx {
-
-using namespace std;
-
-template <class _Tp, class _Hash,
-          bool = is_empty<_Hash>::value && !__libcpp_is_final<_Hash>::value
-        >
-class __hash_map_hasher
-    : private _Hash
-{
-public:
-    _LIBCPP_INLINE_VISIBILITY __hash_map_hasher() : _Hash() {}
-    _LIBCPP_INLINE_VISIBILITY __hash_map_hasher(const _Hash& __h) : _Hash(__h) {}
-    _LIBCPP_INLINE_VISIBILITY const _Hash& hash_function() const {return *this;}
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(const _Tp& __x) const
-        {return static_cast<const _Hash&>(*this)(__x.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(const typename _Tp::first_type& __x) const
-        {return static_cast<const _Hash&>(*this)(__x);}
-};
-
-template <class _Tp, class _Hash>
-class __hash_map_hasher<_Tp, _Hash, false>
-{
-    _Hash __hash_;
-public:
-    _LIBCPP_INLINE_VISIBILITY __hash_map_hasher() : __hash_() {}
-    _LIBCPP_INLINE_VISIBILITY __hash_map_hasher(const _Hash& __h) : __hash_(__h) {}
-    _LIBCPP_INLINE_VISIBILITY const _Hash& hash_function() const {return __hash_;}
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(const _Tp& __x) const
-        {return __hash_(__x.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    size_t operator()(const typename _Tp::first_type& __x) const
-        {return __hash_(__x);}
-};
-
-template <class _Tp, class _Pred,
-          bool = is_empty<_Pred>::value && !__libcpp_is_final<_Pred>::value
-         >
-class __hash_map_equal
-    : private _Pred
-{
-public:
-    _LIBCPP_INLINE_VISIBILITY __hash_map_equal() : _Pred() {}
-    _LIBCPP_INLINE_VISIBILITY __hash_map_equal(const _Pred& __p) : _Pred(__p) {}
-    _LIBCPP_INLINE_VISIBILITY const _Pred& key_eq() const {return *this;}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Tp& __x, const _Tp& __y) const
-        {return static_cast<const _Pred&>(*this)(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const typename _Tp::first_type& __x, const _Tp& __y) const
-        {return static_cast<const _Pred&>(*this)(__x, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Tp& __x, const typename _Tp::first_type& __y) const
-        {return static_cast<const _Pred&>(*this)(__x.first, __y);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const typename _Tp::first_type& __x,
-                    const typename _Tp::first_type& __y) const
-        {return static_cast<const _Pred&>(*this)(__x, __y);}
-};
-
-template <class _Tp, class _Pred>
-class __hash_map_equal<_Tp, _Pred, false>
-{
-    _Pred __pred_;
-public:
-    _LIBCPP_INLINE_VISIBILITY __hash_map_equal() : __pred_() {}
-    _LIBCPP_INLINE_VISIBILITY __hash_map_equal(const _Pred& __p) : __pred_(__p) {}
-    _LIBCPP_INLINE_VISIBILITY const _Pred& key_eq() const {return __pred_;}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Tp& __x, const _Tp& __y) const
-        {return __pred_(__x.first, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const typename _Tp::first_type& __x, const _Tp& __y) const
-        {return __pred_(__x, __y.first);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const _Tp& __x, const typename _Tp::first_type& __y) const
-        {return __pred_(__x.first, __y);}
-    _LIBCPP_INLINE_VISIBILITY
-    bool operator()(const typename _Tp::first_type& __x,
-                    const typename _Tp::first_type& __y) const
-        {return __pred_(__x, __y);}
-};
-
-template <class _Alloc>
-class __hash_map_node_destructor
-{
-    typedef _Alloc                              allocator_type;
-    typedef allocator_traits<allocator_type>    __alloc_traits;
-    typedef typename __alloc_traits::value_type::__node_value_type value_type;
-public:
-    typedef typename __alloc_traits::pointer    pointer;
-private:
-    typedef typename value_type::first_type     first_type;
-    typedef typename value_type::second_type    second_type;
-
-    allocator_type& __na_;
-
-    __hash_map_node_destructor& operator=(const __hash_map_node_destructor&);
-
-public:
-    bool __first_constructed;
-    bool __second_constructed;
-
-    _LIBCPP_INLINE_VISIBILITY
-    explicit __hash_map_node_destructor(allocator_type& __na)
-        : __na_(__na),
-          __first_constructed(false),
-          __second_constructed(false)
-        {}
-
-#ifndef _LIBCPP_CXX03_LANG
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_map_node_destructor(__hash_node_destructor<allocator_type>&& __x)
-        : __na_(__x.__na_),
-          __first_constructed(__x.__value_constructed),
-          __second_constructed(__x.__value_constructed)
-        {
-            __x.__value_constructed = false;
-        }
-#else  // _LIBCPP_CXX03_LANG
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_map_node_destructor(const __hash_node_destructor<allocator_type>& __x)
-        : __na_(__x.__na_),
-          __first_constructed(__x.__value_constructed),
-          __second_constructed(__x.__value_constructed)
-        {
-            const_cast<bool&>(__x.__value_constructed) = false;
-        }
-#endif  // _LIBCPP_CXX03_LANG
-
-    _LIBCPP_INLINE_VISIBILITY
-    void operator()(pointer __p)
-    {
-        if (__second_constructed)
-            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.second));
-        if (__first_constructed)
-            __alloc_traits::destroy(__na_, _VSTD::addressof(__p->__value_.first));
-        if (__p)
-            __alloc_traits::deallocate(__na_, __p, 1);
-    }
-};
-
-template <class _HashIterator>
-class _LIBCPP_TEMPLATE_VIS __hash_map_iterator
-{
-    _HashIterator __i_;
-
-    typedef const typename _HashIterator::value_type::first_type key_type;
-    typedef typename _HashIterator::value_type::second_type      mapped_type;
-public:
-    typedef forward_iterator_tag                                 iterator_category;
-    typedef pair<key_type, mapped_type>                          value_type;
-    typedef typename _HashIterator::difference_type              difference_type;
-    typedef value_type&                                          reference;
-    typedef typename __rebind_pointer<typename _HashIterator::pointer, value_type>::type
-        pointer;
-
-    _LIBCPP_INLINE_VISIBILITY __hash_map_iterator() {}
-
-    _LIBCPP_INLINE_VISIBILITY __hash_map_iterator(_HashIterator __i) : __i_(__i) {}
-
-    _LIBCPP_INLINE_VISIBILITY reference operator*() const {return *operator->();}
-    _LIBCPP_INLINE_VISIBILITY pointer operator->() const {return (pointer)__i_.operator->();}
-
-    _LIBCPP_INLINE_VISIBILITY __hash_map_iterator& operator++() {++__i_; return *this;}
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_map_iterator operator++(int)
-    {
-        __hash_map_iterator __t(*this);
-        ++(*this);
-        return __t;
-    }
-
-    friend _LIBCPP_INLINE_VISIBILITY 
-    bool operator==(const __hash_map_iterator& __x, const __hash_map_iterator& __y)
-        {return __x.__i_ == __y.__i_;}
-    friend _LIBCPP_INLINE_VISIBILITY 
-    bool operator!=(const __hash_map_iterator& __x, const __hash_map_iterator& __y)
-        {return __x.__i_ != __y.__i_;}
-
-    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS hash_map;
-    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS hash_multimap;
-    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
-    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
-    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator;
-};
-
-template <class _HashIterator>
-class _LIBCPP_TEMPLATE_VIS __hash_map_const_iterator
-{
-    _HashIterator __i_;
-
-    typedef const typename _HashIterator::value_type::first_type key_type;
-    typedef typename _HashIterator::value_type::second_type      mapped_type;
-public:
-    typedef forward_iterator_tag                                 iterator_category;
-    typedef pair<key_type, mapped_type>                          value_type;
-    typedef typename _HashIterator::difference_type              difference_type;
-    typedef const value_type&                                    reference;
-    typedef typename __rebind_pointer<typename _HashIterator::pointer, const value_type>::type
-        pointer;
-
-    _LIBCPP_INLINE_VISIBILITY __hash_map_const_iterator() {}
-
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_map_const_iterator(_HashIterator __i) : __i_(__i) {}
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_map_const_iterator(
-            __hash_map_iterator<typename _HashIterator::__non_const_iterator> __i)
-                : __i_(__i.__i_) {}
-
-    _LIBCPP_INLINE_VISIBILITY
-    reference operator*() const {return *operator->();}
-    _LIBCPP_INLINE_VISIBILITY
-    pointer operator->() const {return (pointer)__i_.operator->();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_map_const_iterator& operator++() {++__i_; return *this;}
-    _LIBCPP_INLINE_VISIBILITY
-    __hash_map_const_iterator operator++(int)
-    {
-        __hash_map_const_iterator __t(*this);
-        ++(*this);
-        return __t;
-    }
-
-    friend _LIBCPP_INLINE_VISIBILITY
-    bool operator==(const __hash_map_const_iterator& __x, const __hash_map_const_iterator& __y)
-        {return __x.__i_ == __y.__i_;}
-    friend _LIBCPP_INLINE_VISIBILITY
-    bool operator!=(const __hash_map_const_iterator& __x, const __hash_map_const_iterator& __y)
-        {return __x.__i_ != __y.__i_;}
-
-    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS hash_map;
-    template <class, class, class, class, class> friend class _LIBCPP_TEMPLATE_VIS hash_multimap;
-    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_iterator;
-    template <class> friend class _LIBCPP_TEMPLATE_VIS __hash_const_local_iterator;
-};
-
-template <class _Key, class _Tp, class _Hash = hash<_Key>, class _Pred = equal_to<_Key>,
-          class _Alloc = allocator<pair<const _Key, _Tp> > >
-class _LIBCPP_TEMPLATE_VIS hash_map
-{
-public:
-    // types
-    typedef _Key                                           key_type;
-    typedef _Tp                                            mapped_type;
-    typedef _Tp                                            data_type;
-    typedef _Hash                                          hasher;
-    typedef _Pred                                          key_equal;
-    typedef _Alloc                                         allocator_type;
-    typedef pair<const key_type, mapped_type>              value_type;
-    typedef value_type&                                    reference;
-    typedef const value_type&                              const_reference;
-
-private:
-    typedef pair<key_type, mapped_type>                    __value_type;
-    typedef __hash_map_hasher<__value_type, hasher>   __hasher;
-    typedef __hash_map_equal<__value_type, key_equal> __key_equal;
-    typedef typename __rebind_alloc_helper<allocator_traits<allocator_type>, __value_type>::type __allocator_type;
-
-    typedef __hash_table<__value_type, __hasher,
-                         __key_equal,  __allocator_type>   __table;
-
-    __table __table_;
-
-    typedef typename __table::__node_pointer               __node_pointer;
-    typedef typename __table::__node_const_pointer         __node_const_pointer;
-    typedef typename __table::__node_traits                __node_traits;
-    typedef typename __table::__node_allocator             __node_allocator;
-    typedef typename __table::__node                       __node;
-    typedef __hash_map_node_destructor<__node_allocator>   _Dp;
-    typedef unique_ptr<__node, _Dp>                         __node_holder;
-    typedef allocator_traits<allocator_type>               __alloc_traits;
-public:
-    typedef typename __alloc_traits::pointer         pointer;
-    typedef typename __alloc_traits::const_pointer   const_pointer;
-    typedef typename __alloc_traits::size_type       size_type;
-    typedef typename __alloc_traits::difference_type difference_type;
-
-    typedef __hash_map_iterator<typename __table::iterator>       iterator;
-    typedef __hash_map_const_iterator<typename __table::const_iterator> const_iterator;
-
-    _LIBCPP_INLINE_VISIBILITY hash_map() {__table_.rehash(193);}
-    explicit hash_map(size_type __n, const hasher& __hf = hasher(),
-                           const key_equal& __eql = key_equal());
-    hash_map(size_type __n, const hasher& __hf,
-                  const key_equal& __eql,
-                  const allocator_type& __a);
-    template <class _InputIterator>
-        hash_map(_InputIterator __first, _InputIterator __last);
-    template <class _InputIterator>
-        hash_map(_InputIterator __first, _InputIterator __last,
-                      size_type __n, const hasher& __hf = hasher(),
-                      const key_equal& __eql = key_equal());
-    template <class _InputIterator>
-        hash_map(_InputIterator __first, _InputIterator __last,
-                      size_type __n, const hasher& __hf,
-                      const key_equal& __eql,
-                      const allocator_type& __a);
-    hash_map(const hash_map& __u);
-
-    _LIBCPP_INLINE_VISIBILITY
-    allocator_type get_allocator() const
-        {return allocator_type(__table_.__node_alloc());}
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool      empty() const {return __table_.size() == 0;}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type size() const  {return __table_.size();}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type max_size() const {return __table_.max_size();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator       begin()        {return __table_.begin();}
-    _LIBCPP_INLINE_VISIBILITY
-    iterator       end()          {return __table_.end();}
-    _LIBCPP_INLINE_VISIBILITY
-    const_iterator begin()  const {return __table_.begin();}
-    _LIBCPP_INLINE_VISIBILITY
-    const_iterator end()    const {return __table_.end();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    pair<iterator, bool> insert(const value_type& __x)
-        {return __table_.__insert_unique(__x);}
-    _LIBCPP_INLINE_VISIBILITY
-    iterator insert(const_iterator, const value_type& __x) {return insert(__x).first;}
-    template <class _InputIterator>
-        _LIBCPP_INLINE_VISIBILITY
-        void insert(_InputIterator __first, _InputIterator __last);
-
-    _LIBCPP_INLINE_VISIBILITY
-    void erase(const_iterator __p) {__table_.erase(__p.__i_);}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type erase(const key_type& __k) {return __table_.__erase_unique(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    void erase(const_iterator __first, const_iterator __last)
-        {__table_.erase(__first.__i_, __last.__i_);}
-    _LIBCPP_INLINE_VISIBILITY
-    void clear() {__table_.clear();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    void swap(hash_map& __u) {__table_.swap(__u.__table_);}
-
-    _LIBCPP_INLINE_VISIBILITY
-    hasher hash_funct() const
-        {return __table_.hash_function().hash_function();}
-    _LIBCPP_INLINE_VISIBILITY
-    key_equal key_eq() const
-        {return __table_.key_eq().key_eq();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator       find(const key_type& __k)       {return __table_.find(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type count(const key_type& __k) const {return __table_.__count_unique(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    pair<iterator, iterator>             equal_range(const key_type& __k)
-        {return __table_.__equal_range_unique(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
-        {return __table_.__equal_range_unique(__k);}
-
-    mapped_type& operator[](const key_type& __k);
-
-    _LIBCPP_INLINE_VISIBILITY
-    size_type bucket_count() const {return __table_.bucket_count();}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type max_bucket_count() const {return __table_.max_bucket_count();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    size_type elems_in_bucket(size_type __n) const
-        {return __table_.bucket_size(__n);}
-
-    _LIBCPP_INLINE_VISIBILITY
-    void resize(size_type __n) {__table_.rehash(__n);}
-
-private:
-    __node_holder __construct_node(const key_type& __k);
-};
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(
-        size_type __n, const hasher& __hf, const key_equal& __eql)
-    : __table_(__hf, __eql)
-{
-    __table_.rehash(__n);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(
-        size_type __n, const hasher& __hf, const key_equal& __eql,
-        const allocator_type& __a)
-    : __table_(__hf, __eql, __a)
-{
-    __table_.rehash(__n);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(
-        _InputIterator __first, _InputIterator __last)
-{
-    __table_.rehash(193);
-    insert(__first, __last);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(
-        _InputIterator __first, _InputIterator __last, size_type __n,
-        const hasher& __hf, const key_equal& __eql)
-    : __table_(__hf, __eql)
-{
-    __table_.rehash(__n);
-    insert(__first, __last);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(
-        _InputIterator __first, _InputIterator __last, size_type __n,
-        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
-    : __table_(__hf, __eql, __a)
-{
-    __table_.rehash(__n);
-    insert(__first, __last);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_map(
-        const hash_map& __u)
-    : __table_(__u.__table_)
-{
-    __table_.rehash(__u.bucket_count());
-    insert(__u.begin(), __u.end());
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-typename hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__node_holder
-hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::__construct_node(const key_type& __k)
-{
-    __node_allocator& __na = __table_.__node_alloc();
-    __node_holder __h(__node_traits::allocate(__na, 1), _Dp(__na));
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.first), __k);
-    __h.get_deleter().__first_constructed = true;
-    __node_traits::construct(__na, _VSTD::addressof(__h->__value_.second));
-    __h.get_deleter().__second_constructed = true;
-    return _LIBCPP_EXPLICIT_MOVE(__h);  // explicitly moved for C++03
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-inline
-void
-hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
-                                                       _InputIterator __last)
-{
-    for (; __first != __last; ++__first)
-        __table_.__insert_unique(*__first);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-_Tp&
-hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::operator[](const key_type& __k)
-{
-    iterator __i = find(__k);
-    if (__i != end())
-        return __i->second;
-    __node_holder __h = __construct_node(__k);
-    pair<iterator, bool> __r = __table_.__node_insert_unique(__h.get());
-    __h.release();
-    return __r.first->second;
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-inline _LIBCPP_INLINE_VISIBILITY
-void
-swap(hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
-     hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
-{
-    __x.swap(__y);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-bool
-operator==(const hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
-           const hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
-{
-    if (__x.size() != __y.size())
-        return false;
-    typedef typename hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>::const_iterator
-                                                                 const_iterator;
-    for (const_iterator __i = __x.begin(), __ex = __x.end(), __ey = __y.end();
-            __i != __ex; ++__i)
-    {
-        const_iterator __j = __y.find(__i->first);
-        if (__j == __ey || !(*__i == *__j))
-            return false;
-    }
-    return true;
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-inline _LIBCPP_INLINE_VISIBILITY
-bool
-operator!=(const hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
-           const hash_map<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
-{
-    return !(__x == __y);
-}
-
-template <class _Key, class _Tp, class _Hash = hash<_Key>, class _Pred = equal_to<_Key>,
-          class _Alloc = allocator<pair<const _Key, _Tp> > >
-class _LIBCPP_TEMPLATE_VIS hash_multimap
-{
-public:
-    // types
-    typedef _Key                                           key_type;
-    typedef _Tp                                            mapped_type;
-    typedef _Tp                                            data_type;
-    typedef _Hash                                          hasher;
-    typedef _Pred                                          key_equal;
-    typedef _Alloc                                         allocator_type;
-    typedef pair<const key_type, mapped_type>              value_type;
-    typedef value_type&                                    reference;
-    typedef const value_type&                              const_reference;
-
-private:
-    typedef pair<key_type, mapped_type>                    __value_type;
-    typedef __hash_map_hasher<__value_type, hasher>   __hasher;
-    typedef __hash_map_equal<__value_type, key_equal> __key_equal;
-    typedef typename __rebind_alloc_helper<allocator_traits<allocator_type>, __value_type>::type __allocator_type;
-
-    typedef __hash_table<__value_type, __hasher,
-                         __key_equal,  __allocator_type>   __table;
-
-    __table __table_;
-
-    typedef typename __table::__node_traits                __node_traits;
-    typedef typename __table::__node_allocator             __node_allocator;
-    typedef typename __table::__node                       __node;
-    typedef __hash_map_node_destructor<__node_allocator>   _Dp;
-    typedef unique_ptr<__node, _Dp>                         __node_holder;
-    typedef allocator_traits<allocator_type>               __alloc_traits;
-public:
-    typedef typename __alloc_traits::pointer         pointer;
-    typedef typename __alloc_traits::const_pointer   const_pointer;
-    typedef typename __alloc_traits::size_type       size_type;
-    typedef typename __alloc_traits::difference_type difference_type;
-
-    typedef __hash_map_iterator<typename __table::iterator>       iterator;
-    typedef __hash_map_const_iterator<typename __table::const_iterator> const_iterator;
-
-    _LIBCPP_INLINE_VISIBILITY
-    hash_multimap() {__table_.rehash(193);}
-    explicit hash_multimap(size_type __n, const hasher& __hf = hasher(),
-                                const key_equal& __eql = key_equal());
-    hash_multimap(size_type __n, const hasher& __hf,
-                                const key_equal& __eql,
-                                const allocator_type& __a);
-    template <class _InputIterator>
-        hash_multimap(_InputIterator __first, _InputIterator __last);
-    template <class _InputIterator>
-        hash_multimap(_InputIterator __first, _InputIterator __last,
-                      size_type __n, const hasher& __hf = hasher(),
-                      const key_equal& __eql = key_equal());
-    template <class _InputIterator>
-        hash_multimap(_InputIterator __first, _InputIterator __last,
-                      size_type __n, const hasher& __hf,
-                      const key_equal& __eql,
-                      const allocator_type& __a);
-    hash_multimap(const hash_multimap& __u);
-
-    _LIBCPP_INLINE_VISIBILITY
-    allocator_type get_allocator() const
-        {return allocator_type(__table_.__node_alloc());}
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool      empty() const {return __table_.size() == 0;}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type size() const  {return __table_.size();}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type max_size() const {return __table_.max_size();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator       begin()        {return __table_.begin();}
-    _LIBCPP_INLINE_VISIBILITY
-    iterator       end()          {return __table_.end();}
-    _LIBCPP_INLINE_VISIBILITY
-    const_iterator begin()  const {return __table_.begin();}
-    _LIBCPP_INLINE_VISIBILITY
-    const_iterator end()    const {return __table_.end();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator insert(const value_type& __x) {return __table_.__insert_multi(__x);}
-    _LIBCPP_INLINE_VISIBILITY
-    iterator insert(const_iterator, const value_type& __x) {return insert(__x);}
-    template <class _InputIterator>
-        _LIBCPP_INLINE_VISIBILITY
-        void insert(_InputIterator __first, _InputIterator __last);
-
-    _LIBCPP_INLINE_VISIBILITY
-    void erase(const_iterator __p) {__table_.erase(__p.__i_);}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type erase(const key_type& __k) {return __table_.__erase_multi(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    void erase(const_iterator __first, const_iterator __last)
-        {__table_.erase(__first.__i_, __last.__i_);}
-    _LIBCPP_INLINE_VISIBILITY
-    void clear() {__table_.clear();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    void swap(hash_multimap& __u) {__table_.swap(__u.__table_);}
-
-    _LIBCPP_INLINE_VISIBILITY
-    hasher hash_funct() const
-        {return __table_.hash_function().hash_function();}
-    _LIBCPP_INLINE_VISIBILITY
-    key_equal key_eq() const
-        {return __table_.key_eq().key_eq();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator       find(const key_type& __k)       {return __table_.find(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type count(const key_type& __k) const {return __table_.__count_multi(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    pair<iterator, iterator>             equal_range(const key_type& __k)
-        {return __table_.__equal_range_multi(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
-        {return __table_.__equal_range_multi(__k);}
-
-    _LIBCPP_INLINE_VISIBILITY
-    size_type bucket_count() const {return __table_.bucket_count();}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type max_bucket_count() const {return __table_.max_bucket_count();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    size_type elems_in_bucket(size_type __n) const
-        {return __table_.bucket_size(__n);}
-
-    _LIBCPP_INLINE_VISIBILITY
-    void resize(size_type __n) {__table_.rehash(__n);}
-};
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(
-        size_type __n, const hasher& __hf, const key_equal& __eql)
-    : __table_(__hf, __eql)
-{
-    __table_.rehash(__n);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(
-        size_type __n, const hasher& __hf, const key_equal& __eql,
-        const allocator_type& __a)
-    : __table_(__hf, __eql, __a)
-{
-    __table_.rehash(__n);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(
-        _InputIterator __first, _InputIterator __last)
-{
-    __table_.rehash(193);
-    insert(__first, __last);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(
-        _InputIterator __first, _InputIterator __last, size_type __n,
-        const hasher& __hf, const key_equal& __eql)
-    : __table_(__hf, __eql)
-{
-    __table_.rehash(__n);
-    insert(__first, __last);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(
-        _InputIterator __first, _InputIterator __last, size_type __n,
-        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
-    : __table_(__hf, __eql, __a)
-{
-    __table_.rehash(__n);
-    insert(__first, __last);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::hash_multimap(
-        const hash_multimap& __u)
-    : __table_(__u.__table_)
-{
-    __table_.rehash(__u.bucket_count());
-    insert(__u.begin(), __u.end());
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-inline
-void
-hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
-                                                            _InputIterator __last)
-{
-    for (; __first != __last; ++__first)
-        __table_.__insert_multi(*__first);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-inline _LIBCPP_INLINE_VISIBILITY
-void
-swap(hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
-     hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
-{
-    __x.swap(__y);
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-bool
-operator==(const hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
-           const hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
-{
-    if (__x.size() != __y.size())
-        return false;
-    typedef typename hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>::const_iterator
-                                                                 const_iterator;
-    typedef pair<const_iterator, const_iterator> _EqRng;
-    for (const_iterator __i = __x.begin(), __ex = __x.end(); __i != __ex;)
-    {
-        _EqRng __xeq = __x.equal_range(__i->first);
-        _EqRng __yeq = __y.equal_range(__i->first);
-        if (_VSTD::distance(__xeq.first, __xeq.second) !=
-            _VSTD::distance(__yeq.first, __yeq.second) ||
-                  !_VSTD::is_permutation(__xeq.first, __xeq.second, __yeq.first))
-            return false;
-        __i = __xeq.second;
-    }
-    return true;
-}
-
-template <class _Key, class _Tp, class _Hash, class _Pred, class _Alloc>
-inline _LIBCPP_INLINE_VISIBILITY
-bool
-operator!=(const hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __x,
-           const hash_multimap<_Key, _Tp, _Hash, _Pred, _Alloc>& __y)
-{
-    return !(__x == __y);
-}
-
-} // __gnu_cxx
-
-#endif  // _LIBCPP_HASH_MAP

libcxx/include/ext/hash_set

-// -*- C++ -*-
-//===------------------------- hash_set ------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef _LIBCPP_HASH_SET
-#define _LIBCPP_HASH_SET
-
-/*
-
-    hash_set synopsis
-
-namespace __gnu_cxx
-{
-
-template <class Value, class Hash = hash<Value>, class Pred = equal_to<Value>,
-          class Alloc = allocator<Value>>
-class hash_set
-{
-public:
-    // types
-    typedef Value                                                      key_type;
-    typedef key_type                                                   value_type;
-    typedef Hash                                                       hasher;
-    typedef Pred                                                       key_equal;
-    typedef Alloc                                                      allocator_type;
-    typedef value_type&                                                reference;
-    typedef const value_type&                                          const_reference;
-    typedef typename allocator_traits<allocator_type>::pointer         pointer;
-    typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
-    typedef typename allocator_traits<allocator_type>::size_type       size_type;
-    typedef typename allocator_traits<allocator_type>::difference_type difference_type;
-
-    typedef /unspecified/ iterator;
-    typedef /unspecified/ const_iterator;
-
-    explicit hash_set(size_type n = 193, const hasher& hf = hasher(),
-                           const key_equal& eql = key_equal(),
-                           const allocator_type& a = allocator_type());
-    template <class InputIterator>
-        hash_set(InputIterator f, InputIterator l,
-                      size_type n = 193, const hasher& hf = hasher(),
-                      const key_equal& eql = key_equal(),
-                      const allocator_type& a = allocator_type());
-    hash_set(const hash_set&);
-    ~hash_set();
-    hash_set& operator=(const hash_set&);
-
-    allocator_type get_allocator() const;
-
-    bool      empty() const;
-    size_type size() const;
-    size_type max_size() const;
-
-    iterator       begin();
-    iterator       end();
-    const_iterator begin()  const;
-    const_iterator end()    const;
-
-    pair<iterator, bool> insert(const value_type& obj);
-    template <class InputIterator>
-        void insert(InputIterator first, InputIterator last);
-
-    void erase(const_iterator position);
-    size_type erase(const key_type& k);
-    void erase(const_iterator first, const_iterator last);
-    void clear();
-
-    void swap(hash_set&);
-
-    hasher hash_funct() const;
-    key_equal key_eq() const;
-
-    iterator       find(const key_type& k);
-    const_iterator find(const key_type& k) const;
-    size_type count(const key_type& k) const;
-    pair<iterator, iterator>             equal_range(const key_type& k);
-    pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
-
-    size_type bucket_count() const;
-    size_type max_bucket_count() const;
-
-    size_type elems_in_bucket(size_type n) const;
-
-    void resize(size_type n);
-};
-
-template <class Value, class Hash, class Pred, class Alloc>
-    void swap(hash_set<Value, Hash, Pred, Alloc>& x,
-              hash_set<Value, Hash, Pred, Alloc>& y);
-
-template <class Value, class Hash, class Pred, class Alloc>
-    bool
-    operator==(const hash_set<Value, Hash, Pred, Alloc>& x,
-               const hash_set<Value, Hash, Pred, Alloc>& y);
-
-template <class Value, class Hash, class Pred, class Alloc>
-    bool
-    operator!=(const hash_set<Value, Hash, Pred, Alloc>& x,
-               const hash_set<Value, Hash, Pred, Alloc>& y);
-
-template <class Value, class Hash = hash<Value>, class Pred = equal_to<Value>,
-          class Alloc = allocator<Value>>
-class hash_multiset
-{
-public:
-    // types
-    typedef Value                                                      key_type;
-    typedef key_type                                                   value_type;
-    typedef Hash                                                       hasher;
-    typedef Pred                                                       key_equal;
-    typedef Alloc                                                      allocator_type;
-    typedef value_type&                                                reference;
-    typedef const value_type&                                          const_reference;
-    typedef typename allocator_traits<allocator_type>::pointer         pointer;
-    typedef typename allocator_traits<allocator_type>::const_pointer   const_pointer;
-    typedef typename allocator_traits<allocator_type>::size_type       size_type;
-    typedef typename allocator_traits<allocator_type>::difference_type difference_type;
-
-    typedef /unspecified/ iterator;
-    typedef /unspecified/ const_iterator;
-
-    explicit hash_multiset(size_type n = 193, const hasher& hf = hasher(),
-                           const key_equal& eql = key_equal(),
-                           const allocator_type& a = allocator_type());
-    template <class InputIterator>
-        hash_multiset(InputIterator f, InputIterator l,
-                      size_type n = 193, const hasher& hf = hasher(),
-                      const key_equal& eql = key_equal(),
-                      const allocator_type& a = allocator_type());
-    hash_multiset(const hash_multiset&);
-    ~hash_multiset();
-    hash_multiset& operator=(const hash_multiset&);
-
-    allocator_type get_allocator() const;
-
-    bool      empty() const;
-    size_type size() const;
-    size_type max_size() const;
-
-    iterator       begin();
-    iterator       end();
-    const_iterator begin()  const;
-    const_iterator end()    const;
-
-    iterator insert(const value_type& obj);
-    template <class InputIterator>
-        void insert(InputIterator first, InputIterator last);
-
-    void erase(const_iterator position);
-    size_type erase(const key_type& k);
-    void erase(const_iterator first, const_iterator last);
-    void clear();
-
-    void swap(hash_multiset&);
-
-    hasher hash_funct() const;
-    key_equal key_eq() const;
-
-    iterator       find(const key_type& k);
-    const_iterator find(const key_type& k) const;
-    size_type count(const key_type& k) const;
-    pair<iterator, iterator>             equal_range(const key_type& k);
-    pair<const_iterator, const_iterator> equal_range(const key_type& k) const;
-
-    size_type bucket_count() const;
-    size_type max_bucket_count() const;
-
-    size_type elems_in_bucket(size_type n) const;
-
-    void resize(size_type n);
-};
-
-template <class Value, class Hash, class Pred, class Alloc>
-    void swap(hash_multiset<Value, Hash, Pred, Alloc>& x,
-              hash_multiset<Value, Hash, Pred, Alloc>& y);
-
-template <class Value, class Hash, class Pred, class Alloc>
-    bool
-    operator==(const hash_multiset<Value, Hash, Pred, Alloc>& x,
-               const hash_multiset<Value, Hash, Pred, Alloc>& y);
-
-template <class Value, class Hash, class Pred, class Alloc>
-    bool
-    operator!=(const hash_multiset<Value, Hash, Pred, Alloc>& x,
-               const hash_multiset<Value, Hash, Pred, Alloc>& y);
-}  // __gnu_cxx
-
-*/
-
-#include <__config>
-#include <__hash_table>
-#include <functional>
-#include <ext/__hash>
-
-#if __DEPRECATED
-#if defined(_LIBCPP_WARNING)
-    _LIBCPP_WARNING("Use of the header <ext/hash_set> is deprecated.  Migrate to <unordered_set>")
-#else
-#   warning Use of the header <ext/hash_set> is deprecated.  Migrate to <unordered_set>
-#endif
-#endif
-
-namespace __gnu_cxx {
-
-using namespace std;
-
-template <class _Value, class _Hash = hash<_Value>, class _Pred = equal_to<_Value>,
-          class _Alloc = allocator<_Value> >
-class _LIBCPP_TEMPLATE_VIS hash_set
-{
-public:
-    // types
-    typedef _Value                                                     key_type;
-    typedef key_type                                                   value_type;
-    typedef _Hash                                                      hasher;
-    typedef _Pred                                                      key_equal;
-    typedef _Alloc                                                     allocator_type;
-    typedef value_type&                                                reference;
-    typedef const value_type&                                          const_reference;
-
-private:
-    typedef __hash_table<value_type, hasher, key_equal, allocator_type> __table;
-
-    __table __table_;
-
-public:
-    typedef typename __table::pointer         pointer;
-    typedef typename __table::const_pointer   const_pointer;
-    typedef typename __table::size_type       size_type;
-    typedef typename __table::difference_type difference_type;
-
-    typedef typename __table::const_iterator       iterator;
-    typedef typename __table::const_iterator       const_iterator;
-
-    _LIBCPP_INLINE_VISIBILITY
-    hash_set() {__table_.rehash(193);}
-    explicit hash_set(size_type __n, const hasher& __hf = hasher(),
-                           const key_equal& __eql = key_equal());
-    hash_set(size_type __n, const hasher& __hf, const key_equal& __eql,
-                  const allocator_type& __a);
-    template <class _InputIterator>
-        hash_set(_InputIterator __first, _InputIterator __last);
-    template <class _InputIterator>
-        hash_set(_InputIterator __first, _InputIterator __last,
-                      size_type __n, const hasher& __hf = hasher(),
-                      const key_equal& __eql = key_equal());
-    template <class _InputIterator>
-        hash_set(_InputIterator __first, _InputIterator __last,
-                      size_type __n, const hasher& __hf, const key_equal& __eql,
-                      const allocator_type& __a);
-    hash_set(const hash_set& __u);
-
-    _LIBCPP_INLINE_VISIBILITY
-    allocator_type get_allocator() const
-        {return allocator_type(__table_.__node_alloc());}
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool      empty() const {return __table_.size() == 0;}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type size() const  {return __table_.size();}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type max_size() const {return __table_.max_size();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator       begin()        {return __table_.begin();}
-    _LIBCPP_INLINE_VISIBILITY
-    iterator       end()          {return __table_.end();}
-    _LIBCPP_INLINE_VISIBILITY
-    const_iterator begin()  const {return __table_.begin();}
-    _LIBCPP_INLINE_VISIBILITY
-    const_iterator end()    const {return __table_.end();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    pair<iterator, bool> insert(const value_type& __x)
-        {return __table_.__insert_unique(__x);}
-    _LIBCPP_INLINE_VISIBILITY
-    iterator insert(const_iterator, const value_type& __x) {return insert(__x).first;}
-    template <class _InputIterator>
-        _LIBCPP_INLINE_VISIBILITY
-        void insert(_InputIterator __first, _InputIterator __last);
-
-    _LIBCPP_INLINE_VISIBILITY
-    void erase(const_iterator __p) {__table_.erase(__p);}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type erase(const key_type& __k) {return __table_.__erase_unique(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    void erase(const_iterator __first, const_iterator __last)
-        {__table_.erase(__first, __last);}
-    _LIBCPP_INLINE_VISIBILITY
-    void clear() {__table_.clear();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    void swap(hash_set& __u) {__table_.swap(__u.__table_);}
-
-    _LIBCPP_INLINE_VISIBILITY
-    hasher hash_funct() const {return __table_.hash_function();}
-    _LIBCPP_INLINE_VISIBILITY
-    key_equal key_eq() const {return __table_.key_eq();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator       find(const key_type& __k)       {return __table_.find(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type count(const key_type& __k) const {return __table_.__count_unique(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    pair<iterator, iterator>             equal_range(const key_type& __k)
-        {return __table_.__equal_range_unique(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
-        {return __table_.__equal_range_unique(__k);}
-
-    _LIBCPP_INLINE_VISIBILITY
-    size_type bucket_count() const {return __table_.bucket_count();}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type max_bucket_count() const {return __table_.max_bucket_count();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    size_type elems_in_bucket(size_type __n) const {return __table_.bucket_size(__n);}
-
-    _LIBCPP_INLINE_VISIBILITY
-    void resize(size_type __n) {__table_.rehash(__n);}
-};
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(size_type __n,
-        const hasher& __hf, const key_equal& __eql)
-    : __table_(__hf, __eql)
-{
-    __table_.rehash(__n);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(size_type __n,
-        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
-    : __table_(__hf, __eql, __a)
-{
-    __table_.rehash(__n);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(
-        _InputIterator __first, _InputIterator __last)
-{
-    __table_.rehash(193);
-    insert(__first, __last);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(
-        _InputIterator __first, _InputIterator __last, size_type __n,
-        const hasher& __hf, const key_equal& __eql)
-    : __table_(__hf, __eql)
-{
-    __table_.rehash(__n);
-    insert(__first, __last);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(
-        _InputIterator __first, _InputIterator __last, size_type __n,
-        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
-    : __table_(__hf, __eql, __a)
-{
-    __table_.rehash(__n);
-    insert(__first, __last);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-hash_set<_Value, _Hash, _Pred, _Alloc>::hash_set(
-        const hash_set& __u)
-    : __table_(__u.__table_)
-{
-    __table_.rehash(__u.bucket_count());
-    insert(__u.begin(), __u.end());
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-inline
-void
-hash_set<_Value, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
-                                                    _InputIterator __last)
-{
-    for (; __first != __last; ++__first)
-        __table_.__insert_unique(*__first);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-inline _LIBCPP_INLINE_VISIBILITY
-void
-swap(hash_set<_Value, _Hash, _Pred, _Alloc>& __x,
-     hash_set<_Value, _Hash, _Pred, _Alloc>& __y)
-{
-    __x.swap(__y);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-bool
-operator==(const hash_set<_Value, _Hash, _Pred, _Alloc>& __x,
-           const hash_set<_Value, _Hash, _Pred, _Alloc>& __y)
-{
-    if (__x.size() != __y.size())
-        return false;
-    typedef typename hash_set<_Value, _Hash, _Pred, _Alloc>::const_iterator
-                                                                 const_iterator;
-    for (const_iterator __i = __x.begin(), __ex = __x.end(), __ey = __y.end();
-            __i != __ex; ++__i)
-    {
-        const_iterator __j = __y.find(*__i);
-        if (__j == __ey || !(*__i == *__j))
-            return false;
-    }
-    return true;
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-inline _LIBCPP_INLINE_VISIBILITY
-bool
-operator!=(const hash_set<_Value, _Hash, _Pred, _Alloc>& __x,
-           const hash_set<_Value, _Hash, _Pred, _Alloc>& __y)
-{
-    return !(__x == __y);
-}
-
-template <class _Value, class _Hash = hash<_Value>, class _Pred = equal_to<_Value>,
-          class _Alloc = allocator<_Value> >
-class _LIBCPP_TEMPLATE_VIS hash_multiset
-{
-public:
-    // types
-    typedef _Value                                                     key_type;
-    typedef key_type                                                   value_type;
-    typedef _Hash                                                      hasher;
-    typedef _Pred                                                      key_equal;
-    typedef _Alloc                                                     allocator_type;
-    typedef value_type&                                                reference;
-    typedef const value_type&                                          const_reference;
-
-private:
-    typedef __hash_table<value_type, hasher, key_equal, allocator_type> __table;
-
-    __table __table_;
-
-public:
-    typedef typename __table::pointer         pointer;
-    typedef typename __table::const_pointer   const_pointer;
-    typedef typename __table::size_type       size_type;
-    typedef typename __table::difference_type difference_type;
-
-    typedef typename __table::const_iterator       iterator;
-    typedef typename __table::const_iterator       const_iterator;
-
-    _LIBCPP_INLINE_VISIBILITY
-    hash_multiset() {__table_.rehash(193);}
-    explicit hash_multiset(size_type __n, const hasher& __hf = hasher(),
-                                const key_equal& __eql = key_equal());
-    hash_multiset(size_type __n, const hasher& __hf,
-                       const key_equal& __eql, const allocator_type& __a);
-    template <class _InputIterator>
-        hash_multiset(_InputIterator __first, _InputIterator __last);
-    template <class _InputIterator>
-        hash_multiset(_InputIterator __first, _InputIterator __last,
-                      size_type __n, const hasher& __hf = hasher(),
-                      const key_equal& __eql = key_equal());
-    template <class _InputIterator>
-        hash_multiset(_InputIterator __first, _InputIterator __last,
-                      size_type __n , const hasher& __hf,
-                      const key_equal& __eql, const allocator_type& __a);
-    hash_multiset(const hash_multiset& __u);
-
-    _LIBCPP_INLINE_VISIBILITY
-    allocator_type get_allocator() const
-        {return allocator_type(__table_.__node_alloc());}
-
-    _LIBCPP_INLINE_VISIBILITY
-    bool      empty() const {return __table_.size() == 0;}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type size() const  {return __table_.size();}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type max_size() const {return __table_.max_size();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator       begin()        {return __table_.begin();}
-    _LIBCPP_INLINE_VISIBILITY
-    iterator       end()          {return __table_.end();}
-    _LIBCPP_INLINE_VISIBILITY
-    const_iterator begin()  const {return __table_.begin();}
-    _LIBCPP_INLINE_VISIBILITY
-    const_iterator end()    const {return __table_.end();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator insert(const value_type& __x) {return __table_.__insert_multi(__x);}
-    _LIBCPP_INLINE_VISIBILITY
-    iterator insert(const_iterator, const value_type& __x) {return insert(__x);}
-    template <class _InputIterator>
-        _LIBCPP_INLINE_VISIBILITY
-        void insert(_InputIterator __first, _InputIterator __last);
-
-    _LIBCPP_INLINE_VISIBILITY
-    void erase(const_iterator __p) {__table_.erase(__p);}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type erase(const key_type& __k) {return __table_.__erase_multi(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    void erase(const_iterator __first, const_iterator __last)
-        {__table_.erase(__first, __last);}
-    _LIBCPP_INLINE_VISIBILITY
-    void clear() {__table_.clear();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    void swap(hash_multiset& __u) {__table_.swap(__u.__table_);}
-
-    _LIBCPP_INLINE_VISIBILITY
-    hasher hash_funct() const {return __table_.hash_function();}
-    _LIBCPP_INLINE_VISIBILITY
-    key_equal key_eq() const {return __table_.key_eq();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    iterator       find(const key_type& __k)       {return __table_.find(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    const_iterator find(const key_type& __k) const {return __table_.find(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type count(const key_type& __k) const {return __table_.__count_multi(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    pair<iterator, iterator>             equal_range(const key_type& __k)
-        {return __table_.__equal_range_multi(__k);}
-    _LIBCPP_INLINE_VISIBILITY
-    pair<const_iterator, const_iterator> equal_range(const key_type& __k) const
-        {return __table_.__equal_range_multi(__k);}
-
-    _LIBCPP_INLINE_VISIBILITY
-    size_type bucket_count() const {return __table_.bucket_count();}
-    _LIBCPP_INLINE_VISIBILITY
-    size_type max_bucket_count() const {return __table_.max_bucket_count();}
-
-    _LIBCPP_INLINE_VISIBILITY
-    size_type elems_in_bucket(size_type __n) const {return __table_.bucket_size(__n);}
-
-    _LIBCPP_INLINE_VISIBILITY
-    void resize(size_type __n) {__table_.rehash(__n);}
-};
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(
-        size_type __n, const hasher& __hf, const key_equal& __eql)
-    : __table_(__hf, __eql)
-{
-    __table_.rehash(__n);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(
-        size_type __n, const hasher& __hf, const key_equal& __eql,
-        const allocator_type& __a)
-    : __table_(__hf, __eql, __a)
-{
-    __table_.rehash(__n);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(
-        _InputIterator __first, _InputIterator __last)
-{
-    __table_.rehash(193);
-    insert(__first, __last);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(
-        _InputIterator __first, _InputIterator __last, size_type __n,
-        const hasher& __hf, const key_equal& __eql)
-    : __table_(__hf, __eql)
-{
-    __table_.rehash(__n);
-    insert(__first, __last);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(
-        _InputIterator __first, _InputIterator __last, size_type __n,
-        const hasher& __hf, const key_equal& __eql, const allocator_type& __a)
-    : __table_(__hf, __eql, __a)
-{
-    __table_.rehash(__n);
-    insert(__first, __last);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-hash_multiset<_Value, _Hash, _Pred, _Alloc>::hash_multiset(
-        const hash_multiset& __u)
-    : __table_(__u.__table_)
-{
-    __table_.rehash(__u.bucket_count());
-    insert(__u.begin(), __u.end());
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-template <class _InputIterator>
-inline
-void
-hash_multiset<_Value, _Hash, _Pred, _Alloc>::insert(_InputIterator __first,
-                                                         _InputIterator __last)
-{
-    for (; __first != __last; ++__first)
-        __table_.__insert_multi(*__first);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-inline _LIBCPP_INLINE_VISIBILITY
-void
-swap(hash_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
-     hash_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
-{
-    __x.swap(__y);
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-bool
-operator==(const hash_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
-           const hash_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
-{
-    if (__x.size() != __y.size())
-        return false;
-    typedef typename hash_multiset<_Value, _Hash, _Pred, _Alloc>::const_iterator
-                                                                 const_iterator;
-    typedef pair<const_iterator, const_iterator> _EqRng;
-    for (const_iterator __i = __x.begin(), __ex = __x.end(); __i != __ex;)
-    {
-        _EqRng __xeq = __x.equal_range(*__i);
-        _EqRng __yeq = __y.equal_range(*__i);
-        if (_VSTD::distance(__xeq.first, __xeq.second) !=
-            _VSTD::distance(__yeq.first, __yeq.second) ||
-                  !_VSTD::is_permutation(__xeq.first, __xeq.second, __yeq.first))
-            return false;
-        __i = __xeq.second;
-    }
-    return true;
-}
-
-template <class _Value, class _Hash, class _Pred, class _Alloc>
-inline _LIBCPP_INLINE_VISIBILITY
-bool
-operator!=(const hash_multiset<_Value, _Hash, _Pred, _Alloc>& __x,
-           const hash_multiset<_Value, _Hash, _Pred, _Alloc>& __y)
-{
-    return !(__x == __y);
-}
-
-} // __gnu_cxx
-
-#endif  // _LIBCPP_HASH_SET

libcxx/test/libcxx/containers/gnu_cxx/hash_map.pass.cpp

-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// Prevent emission of the deprecated warning.
-#ifdef __clang__
-#pragma clang diagnostic ignored "-W#warnings"
-#endif
-
-#include <ext/hash_map>
-
-namespace __gnu_cxx {
-template class hash_map<int, int>;
-}
-
-int main() {
-  typedef __gnu_cxx::hash_map<int, int> Map;
-  Map m;
-  Map m2(m);
-  ((void)m2);
-}

libcxx/test/libcxx/containers/gnu_cxx/hash_set.pass.cpp

-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// Prevent emission of the deprecated warning.
-#ifdef __clang__
-#pragma clang diagnostic ignored "-W#warnings"
-#endif
-
-#include <ext/hash_set>
-
-namespace __gnu_cxx {
-template class hash_set<int>;
-}
-
-int main() {
-  typedef __gnu_cxx::hash_set<int> Set;
-  Set s;
-  Set s2(s);
-  ((void)s2);
-}

libcxx/test/libcxx/double_include.sh.cpp

 // -*- C++ -*-
 //===----------------------------------------------------------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 
 // Test that we can include each header in two TU's and link them together.
 
 // RUN: %cxx -c %s -o %t.first.o %flags %compile_flags
 // RUN: %cxx -c %s -o %t.second.o -DWITH_MAIN %flags %compile_flags
 // RUN: %cxx -o %t.exe %t.first.o %t.second.o %flags %link_flags
 // RUN: %run
 
-// Prevent <ext/hash_map> from generating deprecated warnings for this test.
-#if defined(__DEPRECATED)
-#undef __DEPRECATED
-#endif
-
 // Top level headers
 #include <algorithm>
 #include <any>
 #include <array>
 #ifndef _LIBCPP_HAS_NO_THREADS
 #include <atomic>
 #endif
 #include <bit>

 #include <experimental/string>
 #include <experimental/type_traits>
 #include <experimental/unordered_map>
 #include <experimental/unordered_set>
 #include <experimental/utility>
 #include <experimental/vector>
 #endif // __cplusplus >= 201103L
 
-// extended headers
-#include <ext/hash_map>
-#include <ext/hash_set>
-
 #if defined(WITH_MAIN)
 int main() {}
 #endif

libcxx/test/libcxx/extensions/hash/specializations.fail.cpp

-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#include <assert.h>
-#include <ext/hash_map>
-#include <string>
-
-int main()
-{
-    assert(__gnu_cxx::hash<std::string>()(std::string()) == 0);  // error
-}

libcxx/test/libcxx/extensions/hash/specializations.pass.cpp

-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// NOTE: Undefined __DEPRECATED to prevent this test from failing with -Werror
-#undef __DEPRECATED
-#include <assert.h>
-#include <ext/hash_map>
-#include <string>
-
-int main()
-{
-    char str[] = "test";
-    assert(__gnu_cxx::hash<const char *>()("test") ==
-           std::hash<std::string>()("test"));
-    assert(__gnu_cxx::hash<char *>()(str) == std::hash<std::string>()("test"));
-    assert(__gnu_cxx::hash<char>()(42) == 42);
-    assert(__gnu_cxx::hash<signed char>()(42) == 42);
-    assert(__gnu_cxx::hash<unsigned char>()(42) == 42);
-    assert(__gnu_cxx::hash<short>()(42) == 42);
-    assert(__gnu_cxx::hash<unsigned short>()(42) == 42);
-    assert(__gnu_cxx::hash<int>()(42) == 42);
-    assert(__gnu_cxx::hash<unsigned int>()(42) == 42);
-    assert(__gnu_cxx::hash<long>()(42) == 42);
-    assert(__gnu_cxx::hash<unsigned long>()(42) == 42);
-}

libcxx/test/libcxx/extensions/hash_map/const_iterator.fail.cpp

-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#include <ext/hash_map>
-
-int main()
-{
-    __gnu_cxx::hash_map<int, int> m;
-    m[1] = 1;
-    const __gnu_cxx::hash_map<int, int> &cm = m;
-    cm.find(1)->second = 2;  // error
-}

libcxx/test/libcxx/extensions/nothing_to_do.pass.cpp

-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-int main()
-{
-}

libcxx/test/libcxx/min_max_macros.sh.cpp

 TEST_MACROS();
 #include <experimental/unordered_set>
 TEST_MACROS();
 #include <experimental/utility>
 TEST_MACROS();
 #include <experimental/vector>
 TEST_MACROS();
 #endif // __cplusplus >= 201103L
-
-// extended headers
-#include <ext/hash_map>
-TEST_MACROS();
-#include <ext/hash_set>
-TEST_MACROS();