xref: /llvm-project-15.0.7/libcxx/include/memory (revision 43ee367d)
1// -*- C++ -*-
2//===-------------------------- memory ------------------------------------===//
3//
4//                     The LLVM Compiler Infrastructure
5//
6// This file is dual licensed under the MIT and the University of Illinois Open
7// Source Licenses. See LICENSE.TXT for details.
8//
9//===----------------------------------------------------------------------===//
10
11#ifndef _LIBCPP_MEMORY
12#define _LIBCPP_MEMORY
13
14/*
15    memory synopsis
16
17namespace std
18{
19
20struct allocator_arg_t { };
21constexpr allocator_arg_t allocator_arg = allocator_arg_t();
22
23template <class T, class Alloc> struct uses_allocator;
24
25template <class Ptr>
26struct pointer_traits
27{
28    typedef Ptr pointer;
29    typedef <details> element_type;
30    typedef <details> difference_type;
31
32    template <class U> using rebind = <details>;
33
34    static pointer pointer_to(<details>);
35};
36
37template <class T>
38struct pointer_traits<T*>
39{
40    typedef T* pointer;
41    typedef T element_type;
42    typedef ptrdiff_t difference_type;
43
44    template <class U> using rebind = U*;
45
46    static pointer pointer_to(<details>) noexcept;
47};
48
49template <class Alloc>
50struct allocator_traits
51{
52    typedef Alloc                        allocator_type;
53    typedef typename allocator_type::value_type
54                                         value_type;
55
56    typedef Alloc::pointer | value_type* pointer;
57    typedef Alloc::const_pointer
58          | pointer_traits<pointer>::rebind<const value_type>
59                                         const_pointer;
60    typedef Alloc::void_pointer
61          | pointer_traits<pointer>::rebind<void>
62                                         void_pointer;
63    typedef Alloc::const_void_pointer
64          | pointer_traits<pointer>::rebind<const void>
65                                         const_void_pointer;
66    typedef Alloc::difference_type
67          | pointer_traits<pointer>::difference_type
68                                         difference_type;
69    typedef Alloc::size_type
70          | make_unsigned<difference_type>::type
71                                         size_type;
72    typedef Alloc::propagate_on_container_copy_assignment
73          | false_type                   propagate_on_container_copy_assignment;
74    typedef Alloc::propagate_on_container_move_assignment
75          | false_type                   propagate_on_container_move_assignment;
76    typedef Alloc::propagate_on_container_swap
77          | false_type                   propagate_on_container_swap;
78    typedef Alloc::is_always_equal
79          | is_empty                     is_always_equal;
80
81    template <class T> using rebind_alloc  = Alloc::rebind<U>::other | Alloc<T, Args...>;
82    template <class T> using rebind_traits = allocator_traits<rebind_alloc<T>>;
83
84    static pointer allocate(allocator_type& a, size_type n);
85    static pointer allocate(allocator_type& a, size_type n, const_void_pointer hint);
86
87    static void deallocate(allocator_type& a, pointer p, size_type n) noexcept;
88
89    template <class T, class... Args>
90        static void construct(allocator_type& a, T* p, Args&&... args);
91
92    template <class T>
93        static void destroy(allocator_type& a, T* p);
94
95    static size_type max_size(const allocator_type& a); // noexcept in C++14
96
97    static allocator_type
98        select_on_container_copy_construction(const allocator_type& a);
99};
100
101template <>
102class allocator<void>
103{
104public:
105    typedef void*                                 pointer;
106    typedef const void*                           const_pointer;
107    typedef void                                  value_type;
108
109    template <class _Up> struct rebind {typedef allocator<_Up> other;};
110};
111
112template <class T>
113class allocator
114{
115public:
116    typedef size_t                                size_type;
117    typedef ptrdiff_t                             difference_type;
118    typedef T*                                    pointer;
119    typedef const T*                              const_pointer;
120    typedef typename add_lvalue_reference<T>::type       reference;
121    typedef typename add_lvalue_reference<const T>::type const_reference;
122    typedef T                                     value_type;
123
124    template <class U> struct rebind {typedef allocator<U> other;};
125
126    allocator() noexcept;
127    allocator(const allocator&) noexcept;
128    template <class U> allocator(const allocator<U>&) noexcept;
129    ~allocator();
130    pointer address(reference x) const noexcept;
131    const_pointer address(const_reference x) const noexcept;
132    pointer allocate(size_type, allocator<void>::const_pointer hint = 0);
133    void deallocate(pointer p, size_type n) noexcept;
134    size_type max_size() const noexcept;
135    template<class U, class... Args>
136        void construct(U* p, Args&&... args);
137    template <class U>
138        void destroy(U* p);
139};
140
141template <class T, class U>
142bool operator==(const allocator<T>&, const allocator<U>&) noexcept;
143
144template <class T, class U>
145bool operator!=(const allocator<T>&, const allocator<U>&) noexcept;
146
147template <class OutputIterator, class T>
148class raw_storage_iterator
149    : public iterator<output_iterator_tag,
150                      T,                               // purposefully not C++03
151                      ptrdiff_t,                       // purposefully not C++03
152                      T*,                              // purposefully not C++03
153                      raw_storage_iterator&>           // purposefully not C++03
154{
155public:
156    explicit raw_storage_iterator(OutputIterator x);
157    raw_storage_iterator& operator*();
158    raw_storage_iterator& operator=(const T& element);
159    raw_storage_iterator& operator++();
160    raw_storage_iterator  operator++(int);
161};
162
163template <class T> pair<T*,ptrdiff_t> get_temporary_buffer(ptrdiff_t n) noexcept;
164template <class T> void               return_temporary_buffer(T* p) noexcept;
165
166template <class T> T* addressof(T& r) noexcept;
167
168template <class InputIterator, class ForwardIterator>
169ForwardIterator
170uninitialized_copy(InputIterator first, InputIterator last, ForwardIterator result);
171
172template <class InputIterator, class Size, class ForwardIterator>
173ForwardIterator
174uninitialized_copy_n(InputIterator first, Size n, ForwardIterator result);
175
176template <class ForwardIterator, class T>
177void uninitialized_fill(ForwardIterator first, ForwardIterator last, const T& x);
178
179template <class ForwardIterator, class Size, class T>
180ForwardIterator
181uninitialized_fill_n(ForwardIterator first, Size n, const T& x);
182
183template <class Y> struct auto_ptr_ref {};
184
185template<class X>
186class auto_ptr
187{
188public:
189    typedef X element_type;
190
191    explicit auto_ptr(X* p =0) throw();
192    auto_ptr(auto_ptr&) throw();
193    template<class Y> auto_ptr(auto_ptr<Y>&) throw();
194    auto_ptr& operator=(auto_ptr&) throw();
195    template<class Y> auto_ptr& operator=(auto_ptr<Y>&) throw();
196    auto_ptr& operator=(auto_ptr_ref<X> r) throw();
197    ~auto_ptr() throw();
198
199    typename add_lvalue_reference<X>::type operator*() const throw();
200    X* operator->() const throw();
201    X* get() const throw();
202    X* release() throw();
203    void reset(X* p =0) throw();
204
205    auto_ptr(auto_ptr_ref<X>) throw();
206    template<class Y> operator auto_ptr_ref<Y>() throw();
207    template<class Y> operator auto_ptr<Y>() throw();
208};
209
210template <class T>
211struct default_delete
212{
213    constexpr default_delete() noexcept = default;
214    template <class U> default_delete(const default_delete<U>&) noexcept;
215
216    void operator()(T*) const noexcept;
217};
218
219template <class T>
220struct default_delete<T[]>
221{
222    constexpr default_delete() noexcept = default;
223    void operator()(T*) const noexcept;
224    template <class U> void operator()(U*) const = delete;
225};
226
227template <class T, class D = default_delete<T>>
228class unique_ptr
229{
230public:
231    typedef see below pointer;
232    typedef T element_type;
233    typedef D deleter_type;
234
235    // constructors
236    constexpr unique_ptr() noexcept;
237    explicit unique_ptr(pointer p) noexcept;
238    unique_ptr(pointer p, see below d1) noexcept;
239    unique_ptr(pointer p, see below d2) noexcept;
240    unique_ptr(unique_ptr&& u) noexcept;
241    unique_ptr(nullptr_t) noexcept : unique_ptr() { }
242    template <class U, class E>
243        unique_ptr(unique_ptr<U, E>&& u) noexcept;
244    template <class U>
245        unique_ptr(auto_ptr<U>&& u) noexcept;
246
247    // destructor
248    ~unique_ptr();
249
250    // assignment
251    unique_ptr& operator=(unique_ptr&& u) noexcept;
252    template <class U, class E> unique_ptr& operator=(unique_ptr<U, E>&& u) noexcept;
253    unique_ptr& operator=(nullptr_t) noexcept;
254
255    // observers
256    typename add_lvalue_reference<T>::type operator*() const;
257    pointer operator->() const noexcept;
258    pointer get() const noexcept;
259    deleter_type& get_deleter() noexcept;
260    const deleter_type& get_deleter() const noexcept;
261    explicit operator bool() const noexcept;
262
263    // modifiers
264    pointer release() noexcept;
265    void reset(pointer p = pointer()) noexcept;
266    void swap(unique_ptr& u) noexcept;
267};
268
269template <class T, class D>
270class unique_ptr<T[], D>
271{
272public:
273    typedef implementation-defined pointer;
274    typedef T element_type;
275    typedef D deleter_type;
276
277    // constructors
278    constexpr unique_ptr() noexcept;
279    explicit unique_ptr(pointer p) noexcept;
280    unique_ptr(pointer p, see below d) noexcept;
281    unique_ptr(pointer p, see below d) noexcept;
282    unique_ptr(unique_ptr&& u) noexcept;
283    unique_ptr(nullptr_t) noexcept : unique_ptr() { }
284
285    // destructor
286    ~unique_ptr();
287
288    // assignment
289    unique_ptr& operator=(unique_ptr&& u) noexcept;
290    unique_ptr& operator=(nullptr_t) noexcept;
291
292    // observers
293    T& operator[](size_t i) const;
294    pointer get() const noexcept;
295    deleter_type& get_deleter() noexcept;
296    const deleter_type& get_deleter() const noexcept;
297    explicit operator bool() const noexcept;
298
299    // modifiers
300    pointer release() noexcept;
301    void reset(pointer p = pointer()) noexcept;
302    void reset(nullptr_t) noexcept;
303    template <class U> void reset(U) = delete;
304    void swap(unique_ptr& u) noexcept;
305};
306
307template <class T, class D>
308    void swap(unique_ptr<T, D>& x, unique_ptr<T, D>& y) noexcept;
309
310template <class T1, class D1, class T2, class D2>
311    bool operator==(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
312template <class T1, class D1, class T2, class D2>
313    bool operator!=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
314template <class T1, class D1, class T2, class D2>
315    bool operator<(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
316template <class T1, class D1, class T2, class D2>
317    bool operator<=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
318template <class T1, class D1, class T2, class D2>
319    bool operator>(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
320template <class T1, class D1, class T2, class D2>
321    bool operator>=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
322
323template <class T, class D>
324    bool operator==(const unique_ptr<T, D>& x, nullptr_t) noexcept;
325template <class T, class D>
326    bool operator==(nullptr_t, const unique_ptr<T, D>& y) noexcept;
327template <class T, class D>
328    bool operator!=(const unique_ptr<T, D>& x, nullptr_t) noexcept;
329template <class T, class D>
330    bool operator!=(nullptr_t, const unique_ptr<T, D>& y) noexcept;
331
332template <class T, class D>
333    bool operator<(const unique_ptr<T, D>& x, nullptr_t);
334template <class T, class D>
335    bool operator<(nullptr_t, const unique_ptr<T, D>& y);
336template <class T, class D>
337    bool operator<=(const unique_ptr<T, D>& x, nullptr_t);
338template <class T, class D>
339    bool operator<=(nullptr_t, const unique_ptr<T, D>& y);
340template <class T, class D>
341    bool operator>(const unique_ptr<T, D>& x, nullptr_t);
342template <class T, class D>
343    bool operator>(nullptr_t, const unique_ptr<T, D>& y);
344template <class T, class D>
345    bool operator>=(const unique_ptr<T, D>& x, nullptr_t);
346template <class T, class D>
347    bool operator>=(nullptr_t, const unique_ptr<T, D>& y);
348
349class bad_weak_ptr
350    : public std::exception
351{
352    bad_weak_ptr() noexcept;
353};
354
355template<class T, class... Args> unique_ptr<T> make_unique(Args&&... args);     // C++14
356template<class T>                unique_ptr<T> make_unique(size_t n);           // C++14
357template<class T, class... Args> unspecified   make_unique(Args&&...) = delete; // C++14, T == U[N]
358
359template<class T>
360class shared_ptr
361{
362public:
363    typedef T element_type;
364
365    // constructors:
366    constexpr shared_ptr() noexcept;
367    template<class Y> explicit shared_ptr(Y* p);
368    template<class Y, class D> shared_ptr(Y* p, D d);
369    template<class Y, class D, class A> shared_ptr(Y* p, D d, A a);
370    template <class D> shared_ptr(nullptr_t p, D d);
371    template <class D, class A> shared_ptr(nullptr_t p, D d, A a);
372    template<class Y> shared_ptr(const shared_ptr<Y>& r, T *p) noexcept;
373    shared_ptr(const shared_ptr& r) noexcept;
374    template<class Y> shared_ptr(const shared_ptr<Y>& r) noexcept;
375    shared_ptr(shared_ptr&& r) noexcept;
376    template<class Y> shared_ptr(shared_ptr<Y>&& r) noexcept;
377    template<class Y> explicit shared_ptr(const weak_ptr<Y>& r);
378    template<class Y> shared_ptr(auto_ptr<Y>&& r);
379    template <class Y, class D> shared_ptr(unique_ptr<Y, D>&& r);
380    shared_ptr(nullptr_t) : shared_ptr() { }
381
382    // destructor:
383    ~shared_ptr();
384
385    // assignment:
386    shared_ptr& operator=(const shared_ptr& r) noexcept;
387    template<class Y> shared_ptr& operator=(const shared_ptr<Y>& r) noexcept;
388    shared_ptr& operator=(shared_ptr&& r) noexcept;
389    template<class Y> shared_ptr& operator=(shared_ptr<Y>&& r);
390    template<class Y> shared_ptr& operator=(auto_ptr<Y>&& r);
391    template <class Y, class D> shared_ptr& operator=(unique_ptr<Y, D>&& r);
392
393    // modifiers:
394    void swap(shared_ptr& r) noexcept;
395    void reset() noexcept;
396    template<class Y> void reset(Y* p);
397    template<class Y, class D> void reset(Y* p, D d);
398    template<class Y, class D, class A> void reset(Y* p, D d, A a);
399
400    // observers:
401    T* get() const noexcept;
402    T& operator*() const noexcept;
403    T* operator->() const noexcept;
404    long use_count() const noexcept;
405    bool unique() const noexcept;
406    explicit operator bool() const noexcept;
407    template<class U> bool owner_before(shared_ptr<U> const& b) const;
408    template<class U> bool owner_before(weak_ptr<U> const& b) const;
409};
410
411// shared_ptr comparisons:
412template<class T, class U>
413    bool operator==(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
414template<class T, class U>
415    bool operator!=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
416template<class T, class U>
417    bool operator<(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
418template<class T, class U>
419    bool operator>(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
420template<class T, class U>
421    bool operator<=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
422template<class T, class U>
423    bool operator>=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
424
425template <class T>
426    bool operator==(const shared_ptr<T>& x, nullptr_t) noexcept;
427template <class T>
428    bool operator==(nullptr_t, const shared_ptr<T>& y) noexcept;
429template <class T>
430    bool operator!=(const shared_ptr<T>& x, nullptr_t) noexcept;
431template <class T>
432    bool operator!=(nullptr_t, const shared_ptr<T>& y) noexcept;
433template <class T>
434    bool operator<(const shared_ptr<T>& x, nullptr_t) noexcept;
435template <class T>
436bool operator<(nullptr_t, const shared_ptr<T>& y) noexcept;
437template <class T>
438    bool operator<=(const shared_ptr<T>& x, nullptr_t) noexcept;
439template <class T>
440    bool operator<=(nullptr_t, const shared_ptr<T>& y) noexcept;
441template <class T>
442    bool operator>(const shared_ptr<T>& x, nullptr_t) noexcept;
443template <class T>
444    bool operator>(nullptr_t, const shared_ptr<T>& y) noexcept;
445template <class T>
446    bool operator>=(const shared_ptr<T>& x, nullptr_t) noexcept;
447template <class T>
448    bool operator>=(nullptr_t, const shared_ptr<T>& y) noexcept;
449
450// shared_ptr specialized algorithms:
451template<class T> void swap(shared_ptr<T>& a, shared_ptr<T>& b) noexcept;
452
453// shared_ptr casts:
454template<class T, class U>
455    shared_ptr<T> static_pointer_cast(shared_ptr<U> const& r) noexcept;
456template<class T, class U>
457    shared_ptr<T> dynamic_pointer_cast(shared_ptr<U> const& r) noexcept;
458template<class T, class U>
459    shared_ptr<T> const_pointer_cast(shared_ptr<U> const& r) noexcept;
460
461// shared_ptr I/O:
462template<class E, class T, class Y>
463    basic_ostream<E, T>& operator<< (basic_ostream<E, T>& os, shared_ptr<Y> const& p);
464
465// shared_ptr get_deleter:
466template<class D, class T> D* get_deleter(shared_ptr<T> const& p) noexcept;
467
468template<class T, class... Args>
469    shared_ptr<T> make_shared(Args&&... args);
470template<class T, class A, class... Args>
471    shared_ptr<T> allocate_shared(const A& a, Args&&... args);
472
473template<class T>
474class weak_ptr
475{
476public:
477    typedef T element_type;
478
479    // constructors
480    constexpr weak_ptr() noexcept;
481    template<class Y> weak_ptr(shared_ptr<Y> const& r) noexcept;
482    weak_ptr(weak_ptr const& r) noexcept;
483    template<class Y> weak_ptr(weak_ptr<Y> const& r) noexcept;
484    weak_ptr(weak_ptr&& r) noexcept;                      // C++14
485    template<class Y> weak_ptr(weak_ptr<Y>&& r) noexcept; // C++14
486
487    // destructor
488    ~weak_ptr();
489
490    // assignment
491    weak_ptr& operator=(weak_ptr const& r) noexcept;
492    template<class Y> weak_ptr& operator=(weak_ptr<Y> const& r) noexcept;
493    template<class Y> weak_ptr& operator=(shared_ptr<Y> const& r) noexcept;
494    weak_ptr& operator=(weak_ptr&& r) noexcept;                      // C++14
495    template<class Y> weak_ptr& operator=(weak_ptr<Y>&& r) noexcept; // C++14
496
497    // modifiers
498    void swap(weak_ptr& r) noexcept;
499    void reset() noexcept;
500
501    // observers
502    long use_count() const noexcept;
503    bool expired() const noexcept;
504    shared_ptr<T> lock() const noexcept;
505    template<class U> bool owner_before(shared_ptr<U> const& b) const;
506    template<class U> bool owner_before(weak_ptr<U> const& b) const;
507};
508
509// weak_ptr specialized algorithms:
510template<class T> void swap(weak_ptr<T>& a, weak_ptr<T>& b) noexcept;
511
512// class owner_less:
513template<class T> struct owner_less;
514
515template<class T>
516struct owner_less<shared_ptr<T>>
517    : binary_function<shared_ptr<T>, shared_ptr<T>, bool>
518{
519    typedef bool result_type;
520    bool operator()(shared_ptr<T> const&, shared_ptr<T> const&) const;
521    bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const;
522    bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const;
523};
524
525template<class T>
526struct owner_less<weak_ptr<T>>
527    : binary_function<weak_ptr<T>, weak_ptr<T>, bool>
528{
529    typedef bool result_type;
530    bool operator()(weak_ptr<T> const&, weak_ptr<T> const&) const;
531    bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const;
532    bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const;
533};
534
535template<class T>
536class enable_shared_from_this
537{
538protected:
539    constexpr enable_shared_from_this() noexcept;
540    enable_shared_from_this(enable_shared_from_this const&) noexcept;
541    enable_shared_from_this& operator=(enable_shared_from_this const&) noexcept;
542    ~enable_shared_from_this();
543public:
544    shared_ptr<T> shared_from_this();
545    shared_ptr<T const> shared_from_this() const;
546};
547
548template<class T>
549    bool atomic_is_lock_free(const shared_ptr<T>* p);
550template<class T>
551    shared_ptr<T> atomic_load(const shared_ptr<T>* p);
552template<class T>
553    shared_ptr<T> atomic_load_explicit(const shared_ptr<T>* p, memory_order mo);
554template<class T>
555    void atomic_store(shared_ptr<T>* p, shared_ptr<T> r);
556template<class T>
557    void atomic_store_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
558template<class T>
559    shared_ptr<T> atomic_exchange(shared_ptr<T>* p, shared_ptr<T> r);
560template<class T>
561    shared_ptr<T>
562    atomic_exchange_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
563template<class T>
564    bool
565    atomic_compare_exchange_weak(shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
566template<class T>
567    bool
568    atomic_compare_exchange_strong( shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
569template<class T>
570    bool
571    atomic_compare_exchange_weak_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
572                                          shared_ptr<T> w, memory_order success,
573                                          memory_order failure);
574template<class T>
575    bool
576    atomic_compare_exchange_strong_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
577                                            shared_ptr<T> w, memory_order success,
578                                            memory_order failure);
579// Hash support
580template <class T> struct hash;
581template <class T, class D> struct hash<unique_ptr<T, D> >;
582template <class T> struct hash<shared_ptr<T> >;
583
584// Pointer safety
585enum class pointer_safety { relaxed, preferred, strict };
586void declare_reachable(void *p);
587template <class T> T *undeclare_reachable(T *p);
588void declare_no_pointers(char *p, size_t n);
589void undeclare_no_pointers(char *p, size_t n);
590pointer_safety get_pointer_safety() noexcept;
591
592void* align(size_t alignment, size_t size, void*& ptr, size_t& space);
593
594}  // std
595
596*/
597
598#include <__config>
599#include <type_traits>
600#include <typeinfo>
601#include <cstddef>
602#include <cstdint>
603#include <new>
604#include <utility>
605#include <limits>
606#include <iterator>
607#include <__functional_base>
608#include <iosfwd>
609#include <tuple>
610#include <cstring>
611#if defined(_LIBCPP_NO_EXCEPTIONS)
612    #include <cassert>
613#endif
614
615#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
616#  include <atomic>
617#endif
618
619#include <__undef_min_max>
620#include <__undef___deallocate>
621
622#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
623#pragma GCC system_header
624#endif
625
626_LIBCPP_BEGIN_NAMESPACE_STD
627
628template <class _ValueType>
629inline _LIBCPP_ALWAYS_INLINE
630_ValueType __libcpp_relaxed_load(_ValueType const* __value) {
631#if !defined(_LIBCPP_HAS_NO_THREADS) && \
632    defined(__ATOMIC_RELAXED) &&        \
633    (__has_builtin(__atomic_load_n) || _GNUC_VER >= 407)
634    return __atomic_load_n(__value, __ATOMIC_RELAXED);
635#else
636    return *__value;
637#endif
638}
639
640// addressof moved to <__functional_base>
641
642template <class _Tp> class allocator;
643
644template <>
645class _LIBCPP_TYPE_VIS_ONLY allocator<void>
646{
647public:
648    typedef void*             pointer;
649    typedef const void*       const_pointer;
650    typedef void              value_type;
651
652    template <class _Up> struct rebind {typedef allocator<_Up> other;};
653};
654
655template <>
656class _LIBCPP_TYPE_VIS_ONLY allocator<const void>
657{
658public:
659    typedef const void*       pointer;
660    typedef const void*       const_pointer;
661    typedef const void        value_type;
662
663    template <class _Up> struct rebind {typedef allocator<_Up> other;};
664};
665
666// pointer_traits
667
668template <class _Tp>
669struct __has_element_type
670{
671private:
672    struct __two {char __lx; char __lxx;};
673    template <class _Up> static __two __test(...);
674    template <class _Up> static char __test(typename _Up::element_type* = 0);
675public:
676    static const bool value = sizeof(__test<_Tp>(0)) == 1;
677};
678
679template <class _Ptr, bool = __has_element_type<_Ptr>::value>
680struct __pointer_traits_element_type;
681
682template <class _Ptr>
683struct __pointer_traits_element_type<_Ptr, true>
684{
685    typedef typename _Ptr::element_type type;
686};
687
688#ifndef _LIBCPP_HAS_NO_VARIADICS
689
690template <template <class, class...> class _Sp, class _Tp, class ..._Args>
691struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, true>
692{
693    typedef typename _Sp<_Tp, _Args...>::element_type type;
694};
695
696template <template <class, class...> class _Sp, class _Tp, class ..._Args>
697struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, false>
698{
699    typedef _Tp type;
700};
701
702#else  // _LIBCPP_HAS_NO_VARIADICS
703
704template <template <class> class _Sp, class _Tp>
705struct __pointer_traits_element_type<_Sp<_Tp>, true>
706{
707    typedef typename _Sp<_Tp>::element_type type;
708};
709
710template <template <class> class _Sp, class _Tp>
711struct __pointer_traits_element_type<_Sp<_Tp>, false>
712{
713    typedef _Tp type;
714};
715
716template <template <class, class> class _Sp, class _Tp, class _A0>
717struct __pointer_traits_element_type<_Sp<_Tp, _A0>, true>
718{
719    typedef typename _Sp<_Tp, _A0>::element_type type;
720};
721
722template <template <class, class> class _Sp, class _Tp, class _A0>
723struct __pointer_traits_element_type<_Sp<_Tp, _A0>, false>
724{
725    typedef _Tp type;
726};
727
728template <template <class, class, class> class _Sp, class _Tp, class _A0, class _A1>
729struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1>, true>
730{
731    typedef typename _Sp<_Tp, _A0, _A1>::element_type type;
732};
733
734template <template <class, class, class> class _Sp, class _Tp, class _A0, class _A1>
735struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1>, false>
736{
737    typedef _Tp type;
738};
739
740template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
741                                                           class _A1, class _A2>
742struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1, _A2>, true>
743{
744    typedef typename _Sp<_Tp, _A0, _A1, _A2>::element_type type;
745};
746
747template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
748                                                           class _A1, class _A2>
749struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1, _A2>, false>
750{
751    typedef _Tp type;
752};
753
754#endif  // _LIBCPP_HAS_NO_VARIADICS
755
756template <class _Tp>
757struct __has_difference_type
758{
759private:
760    struct __two {char __lx; char __lxx;};
761    template <class _Up> static __two __test(...);
762    template <class _Up> static char __test(typename _Up::difference_type* = 0);
763public:
764    static const bool value = sizeof(__test<_Tp>(0)) == 1;
765};
766
767template <class _Ptr, bool = __has_difference_type<_Ptr>::value>
768struct __pointer_traits_difference_type
769{
770    typedef ptrdiff_t type;
771};
772
773template <class _Ptr>
774struct __pointer_traits_difference_type<_Ptr, true>
775{
776    typedef typename _Ptr::difference_type type;
777};
778
779template <class _Tp, class _Up>
780struct __has_rebind
781{
782private:
783    struct __two {char __lx; char __lxx;};
784    template <class _Xp> static __two __test(...);
785    template <class _Xp> static char __test(typename _Xp::template rebind<_Up>* = 0);
786public:
787    static const bool value = sizeof(__test<_Tp>(0)) == 1;
788};
789
790template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
791struct __pointer_traits_rebind
792{
793#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
794    typedef typename _Tp::template rebind<_Up> type;
795#else
796    typedef typename _Tp::template rebind<_Up>::other type;
797#endif
798};
799
800#ifndef _LIBCPP_HAS_NO_VARIADICS
801
802template <template <class, class...> class _Sp, class _Tp, class ..._Args, class _Up>
803struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, true>
804{
805#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
806    typedef typename _Sp<_Tp, _Args...>::template rebind<_Up> type;
807#else
808    typedef typename _Sp<_Tp, _Args...>::template rebind<_Up>::other type;
809#endif
810};
811
812template <template <class, class...> class _Sp, class _Tp, class ..._Args, class _Up>
813struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, false>
814{
815    typedef _Sp<_Up, _Args...> type;
816};
817
818#else  // _LIBCPP_HAS_NO_VARIADICS
819
820template <template <class> class _Sp, class _Tp, class _Up>
821struct __pointer_traits_rebind<_Sp<_Tp>, _Up, true>
822{
823#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
824    typedef typename _Sp<_Tp>::template rebind<_Up> type;
825#else
826    typedef typename _Sp<_Tp>::template rebind<_Up>::other type;
827#endif
828};
829
830template <template <class> class _Sp, class _Tp, class _Up>
831struct __pointer_traits_rebind<_Sp<_Tp>, _Up, false>
832{
833    typedef _Sp<_Up> type;
834};
835
836template <template <class, class> class _Sp, class _Tp, class _A0, class _Up>
837struct __pointer_traits_rebind<_Sp<_Tp, _A0>, _Up, true>
838{
839#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
840    typedef typename _Sp<_Tp, _A0>::template rebind<_Up> type;
841#else
842    typedef typename _Sp<_Tp, _A0>::template rebind<_Up>::other type;
843#endif
844};
845
846template <template <class, class> class _Sp, class _Tp, class _A0, class _Up>
847struct __pointer_traits_rebind<_Sp<_Tp, _A0>, _Up, false>
848{
849    typedef _Sp<_Up, _A0> type;
850};
851
852template <template <class, class, class> class _Sp, class _Tp, class _A0,
853                                         class _A1, class _Up>
854struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1>, _Up, true>
855{
856#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
857    typedef typename _Sp<_Tp, _A0, _A1>::template rebind<_Up> type;
858#else
859    typedef typename _Sp<_Tp, _A0, _A1>::template rebind<_Up>::other type;
860#endif
861};
862
863template <template <class, class, class> class _Sp, class _Tp, class _A0,
864                                         class _A1, class _Up>
865struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1>, _Up, false>
866{
867    typedef _Sp<_Up, _A0, _A1> type;
868};
869
870template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
871                                                class _A1, class _A2, class _Up>
872struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1, _A2>, _Up, true>
873{
874#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
875    typedef typename _Sp<_Tp, _A0, _A1, _A2>::template rebind<_Up> type;
876#else
877    typedef typename _Sp<_Tp, _A0, _A1, _A2>::template rebind<_Up>::other type;
878#endif
879};
880
881template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
882                                                class _A1, class _A2, class _Up>
883struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1, _A2>, _Up, false>
884{
885    typedef _Sp<_Up, _A0, _A1, _A2> type;
886};
887
888#endif  // _LIBCPP_HAS_NO_VARIADICS
889
890template <class _Ptr>
891struct _LIBCPP_TYPE_VIS_ONLY pointer_traits
892{
893    typedef _Ptr                                                     pointer;
894    typedef typename __pointer_traits_element_type<pointer>::type    element_type;
895    typedef typename __pointer_traits_difference_type<pointer>::type difference_type;
896
897#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
898    template <class _Up> using rebind = typename __pointer_traits_rebind<pointer, _Up>::type;
899#else
900    template <class _Up> struct rebind
901        {typedef typename __pointer_traits_rebind<pointer, _Up>::type other;};
902#endif  // _LIBCPP_HAS_NO_TEMPLATE_ALIASES
903
904private:
905    struct __nat {};
906public:
907    _LIBCPP_INLINE_VISIBILITY
908    static pointer pointer_to(typename conditional<is_void<element_type>::value,
909                                           __nat, element_type>::type& __r)
910        {return pointer::pointer_to(__r);}
911};
912
913template <class _Tp>
914struct _LIBCPP_TYPE_VIS_ONLY pointer_traits<_Tp*>
915{
916    typedef _Tp*      pointer;
917    typedef _Tp       element_type;
918    typedef ptrdiff_t difference_type;
919
920#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
921    template <class _Up> using rebind = _Up*;
922#else
923    template <class _Up> struct rebind {typedef _Up* other;};
924#endif
925
926private:
927    struct __nat {};
928public:
929    _LIBCPP_INLINE_VISIBILITY
930    static pointer pointer_to(typename conditional<is_void<element_type>::value,
931                                      __nat, element_type>::type& __r) _NOEXCEPT
932        {return _VSTD::addressof(__r);}
933};
934
935template <class _From, class _To>
936struct __rebind_pointer {
937#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
938    typedef typename pointer_traits<_From>::template rebind<_To>        type;
939#else
940    typedef typename pointer_traits<_From>::template rebind<_To>::other type;
941#endif
942};
943
944// allocator_traits
945
946namespace __has_pointer_type_imp
947{
948    template <class _Up> static __two __test(...);
949    template <class _Up> static char __test(typename _Up::pointer* = 0);
950}
951
952template <class _Tp>
953struct __has_pointer_type
954    : public integral_constant<bool, sizeof(__has_pointer_type_imp::__test<_Tp>(0)) == 1>
955{
956};
957
958namespace __pointer_type_imp
959{
960
961template <class _Tp, class _Dp, bool = __has_pointer_type<_Dp>::value>
962struct __pointer_type
963{
964    typedef typename _Dp::pointer type;
965};
966
967template <class _Tp, class _Dp>
968struct __pointer_type<_Tp, _Dp, false>
969{
970    typedef _Tp* type;
971};
972
973}  // __pointer_type_imp
974
975template <class _Tp, class _Dp>
976struct __pointer_type
977{
978    typedef typename __pointer_type_imp::__pointer_type<_Tp, typename remove_reference<_Dp>::type>::type type;
979};
980
981template <class _Tp>
982struct __has_const_pointer
983{
984private:
985    struct __two {char __lx; char __lxx;};
986    template <class _Up> static __two __test(...);
987    template <class _Up> static char __test(typename _Up::const_pointer* = 0);
988public:
989    static const bool value = sizeof(__test<_Tp>(0)) == 1;
990};
991
992template <class _Tp, class _Ptr, class _Alloc, bool = __has_const_pointer<_Alloc>::value>
993struct __const_pointer
994{
995    typedef typename _Alloc::const_pointer type;
996};
997
998template <class _Tp, class _Ptr, class _Alloc>
999struct __const_pointer<_Tp, _Ptr, _Alloc, false>
1000{
1001#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1002    typedef typename pointer_traits<_Ptr>::template rebind<const _Tp> type;
1003#else
1004    typedef typename pointer_traits<_Ptr>::template rebind<const _Tp>::other type;
1005#endif
1006};
1007
1008template <class _Tp>
1009struct __has_void_pointer
1010{
1011private:
1012    struct __two {char __lx; char __lxx;};
1013    template <class _Up> static __two __test(...);
1014    template <class _Up> static char __test(typename _Up::void_pointer* = 0);
1015public:
1016    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1017};
1018
1019template <class _Ptr, class _Alloc, bool = __has_void_pointer<_Alloc>::value>
1020struct __void_pointer
1021{
1022    typedef typename _Alloc::void_pointer type;
1023};
1024
1025template <class _Ptr, class _Alloc>
1026struct __void_pointer<_Ptr, _Alloc, false>
1027{
1028#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1029    typedef typename pointer_traits<_Ptr>::template rebind<void> type;
1030#else
1031    typedef typename pointer_traits<_Ptr>::template rebind<void>::other type;
1032#endif
1033};
1034
1035template <class _Tp>
1036struct __has_const_void_pointer
1037{
1038private:
1039    struct __two {char __lx; char __lxx;};
1040    template <class _Up> static __two __test(...);
1041    template <class _Up> static char __test(typename _Up::const_void_pointer* = 0);
1042public:
1043    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1044};
1045
1046template <class _Ptr, class _Alloc, bool = __has_const_void_pointer<_Alloc>::value>
1047struct __const_void_pointer
1048{
1049    typedef typename _Alloc::const_void_pointer type;
1050};
1051
1052template <class _Ptr, class _Alloc>
1053struct __const_void_pointer<_Ptr, _Alloc, false>
1054{
1055#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1056    typedef typename pointer_traits<_Ptr>::template rebind<const void> type;
1057#else
1058    typedef typename pointer_traits<_Ptr>::template rebind<const void>::other type;
1059#endif
1060};
1061
1062template <class _Tp>
1063inline _LIBCPP_INLINE_VISIBILITY
1064_Tp*
1065__to_raw_pointer(_Tp* __p) _NOEXCEPT
1066{
1067    return __p;
1068}
1069
1070template <class _Pointer>
1071inline _LIBCPP_INLINE_VISIBILITY
1072typename pointer_traits<_Pointer>::element_type*
1073__to_raw_pointer(_Pointer __p) _NOEXCEPT
1074{
1075    return _VSTD::__to_raw_pointer(__p.operator->());
1076}
1077
1078template <class _Tp>
1079struct __has_size_type
1080{
1081private:
1082    struct __two {char __lx; char __lxx;};
1083    template <class _Up> static __two __test(...);
1084    template <class _Up> static char __test(typename _Up::size_type* = 0);
1085public:
1086    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1087};
1088
1089template <class _Alloc, class _DiffType, bool = __has_size_type<_Alloc>::value>
1090struct __size_type
1091{
1092    typedef typename make_unsigned<_DiffType>::type type;
1093};
1094
1095template <class _Alloc, class _DiffType>
1096struct __size_type<_Alloc, _DiffType, true>
1097{
1098    typedef typename _Alloc::size_type type;
1099};
1100
1101template <class _Tp>
1102struct __has_propagate_on_container_copy_assignment
1103{
1104private:
1105    struct __two {char __lx; char __lxx;};
1106    template <class _Up> static __two __test(...);
1107    template <class _Up> static char __test(typename _Up::propagate_on_container_copy_assignment* = 0);
1108public:
1109    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1110};
1111
1112template <class _Alloc, bool = __has_propagate_on_container_copy_assignment<_Alloc>::value>
1113struct __propagate_on_container_copy_assignment
1114{
1115    typedef false_type type;
1116};
1117
1118template <class _Alloc>
1119struct __propagate_on_container_copy_assignment<_Alloc, true>
1120{
1121    typedef typename _Alloc::propagate_on_container_copy_assignment type;
1122};
1123
1124template <class _Tp>
1125struct __has_propagate_on_container_move_assignment
1126{
1127private:
1128    struct __two {char __lx; char __lxx;};
1129    template <class _Up> static __two __test(...);
1130    template <class _Up> static char __test(typename _Up::propagate_on_container_move_assignment* = 0);
1131public:
1132    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1133};
1134
1135template <class _Alloc, bool = __has_propagate_on_container_move_assignment<_Alloc>::value>
1136struct __propagate_on_container_move_assignment
1137{
1138    typedef false_type type;
1139};
1140
1141template <class _Alloc>
1142struct __propagate_on_container_move_assignment<_Alloc, true>
1143{
1144    typedef typename _Alloc::propagate_on_container_move_assignment type;
1145};
1146
1147template <class _Tp>
1148struct __has_propagate_on_container_swap
1149{
1150private:
1151    struct __two {char __lx; char __lxx;};
1152    template <class _Up> static __two __test(...);
1153    template <class _Up> static char __test(typename _Up::propagate_on_container_swap* = 0);
1154public:
1155    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1156};
1157
1158template <class _Alloc, bool = __has_propagate_on_container_swap<_Alloc>::value>
1159struct __propagate_on_container_swap
1160{
1161    typedef false_type type;
1162};
1163
1164template <class _Alloc>
1165struct __propagate_on_container_swap<_Alloc, true>
1166{
1167    typedef typename _Alloc::propagate_on_container_swap type;
1168};
1169
1170template <class _Tp>
1171struct __has_is_always_equal
1172{
1173private:
1174    struct __two {char __lx; char __lxx;};
1175    template <class _Up> static __two __test(...);
1176    template <class _Up> static char __test(typename _Up::is_always_equal* = 0);
1177public:
1178    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1179};
1180
1181template <class _Alloc, bool = __has_is_always_equal<_Alloc>::value>
1182struct __is_always_equal
1183{
1184    typedef typename _VSTD::is_empty<_Alloc>::type type;
1185};
1186
1187template <class _Alloc>
1188struct __is_always_equal<_Alloc, true>
1189{
1190    typedef typename _Alloc::is_always_equal type;
1191};
1192
1193template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
1194struct __has_rebind_other
1195{
1196private:
1197    struct __two {char __lx; char __lxx;};
1198    template <class _Xp> static __two __test(...);
1199    template <class _Xp> static char __test(typename _Xp::template rebind<_Up>::other* = 0);
1200public:
1201    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1202};
1203
1204template <class _Tp, class _Up>
1205struct __has_rebind_other<_Tp, _Up, false>
1206{
1207    static const bool value = false;
1208};
1209
1210template <class _Tp, class _Up, bool = __has_rebind_other<_Tp, _Up>::value>
1211struct __allocator_traits_rebind
1212{
1213    typedef typename _Tp::template rebind<_Up>::other type;
1214};
1215
1216#ifndef _LIBCPP_HAS_NO_VARIADICS
1217
1218template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up>
1219struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, true>
1220{
1221    typedef typename _Alloc<_Tp, _Args...>::template rebind<_Up>::other type;
1222};
1223
1224template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up>
1225struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, false>
1226{
1227    typedef _Alloc<_Up, _Args...> type;
1228};
1229
1230#else  // _LIBCPP_HAS_NO_VARIADICS
1231
1232template <template <class> class _Alloc, class _Tp, class _Up>
1233struct __allocator_traits_rebind<_Alloc<_Tp>, _Up, true>
1234{
1235    typedef typename _Alloc<_Tp>::template rebind<_Up>::other type;
1236};
1237
1238template <template <class> class _Alloc, class _Tp, class _Up>
1239struct __allocator_traits_rebind<_Alloc<_Tp>, _Up, false>
1240{
1241    typedef _Alloc<_Up> type;
1242};
1243
1244template <template <class, class> class _Alloc, class _Tp, class _A0, class _Up>
1245struct __allocator_traits_rebind<_Alloc<_Tp, _A0>, _Up, true>
1246{
1247    typedef typename _Alloc<_Tp, _A0>::template rebind<_Up>::other type;
1248};
1249
1250template <template <class, class> class _Alloc, class _Tp, class _A0, class _Up>
1251struct __allocator_traits_rebind<_Alloc<_Tp, _A0>, _Up, false>
1252{
1253    typedef _Alloc<_Up, _A0> type;
1254};
1255
1256template <template <class, class, class> class _Alloc, class _Tp, class _A0,
1257                                         class _A1, class _Up>
1258struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1>, _Up, true>
1259{
1260    typedef typename _Alloc<_Tp, _A0, _A1>::template rebind<_Up>::other type;
1261};
1262
1263template <template <class, class, class> class _Alloc, class _Tp, class _A0,
1264                                         class _A1, class _Up>
1265struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1>, _Up, false>
1266{
1267    typedef _Alloc<_Up, _A0, _A1> type;
1268};
1269
1270template <template <class, class, class, class> class _Alloc, class _Tp, class _A0,
1271                                                class _A1, class _A2, class _Up>
1272struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1, _A2>, _Up, true>
1273{
1274    typedef typename _Alloc<_Tp, _A0, _A1, _A2>::template rebind<_Up>::other type;
1275};
1276
1277template <template <class, class, class, class> class _Alloc, class _Tp, class _A0,
1278                                                class _A1, class _A2, class _Up>
1279struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1, _A2>, _Up, false>
1280{
1281    typedef _Alloc<_Up, _A0, _A1, _A2> type;
1282};
1283
1284#endif  // _LIBCPP_HAS_NO_VARIADICS
1285
1286#ifndef _LIBCPP_HAS_NO_ADVANCED_SFINAE
1287
1288template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1289auto
1290__has_allocate_hint_test(_Alloc&& __a, _SizeType&& __sz, _ConstVoidPtr&& __p)
1291    -> decltype(__a.allocate(__sz, __p), true_type());
1292
1293template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1294auto
1295__has_allocate_hint_test(const _Alloc& __a, _SizeType&& __sz, _ConstVoidPtr&& __p)
1296    -> false_type;
1297
1298template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1299struct __has_allocate_hint
1300    : integral_constant<bool,
1301        is_same<
1302            decltype(__has_allocate_hint_test(declval<_Alloc>(),
1303                                          declval<_SizeType>(),
1304                                          declval<_ConstVoidPtr>())),
1305            true_type>::value>
1306{
1307};
1308
1309#else  // _LIBCPP_HAS_NO_ADVANCED_SFINAE
1310
1311template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1312struct __has_allocate_hint
1313    : true_type
1314{
1315};
1316
1317#endif  // _LIBCPP_HAS_NO_ADVANCED_SFINAE
1318
1319#if !defined(_LIBCPP_HAS_NO_ADVANCED_SFINAE) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1320
1321template <class _Alloc, class _Tp, class ..._Args>
1322decltype(_VSTD::declval<_Alloc>().construct(_VSTD::declval<_Tp*>(),
1323                                           _VSTD::declval<_Args>()...),
1324                                           true_type())
1325__has_construct_test(_Alloc&& __a, _Tp* __p, _Args&& ...__args);
1326
1327template <class _Alloc, class _Pointer, class ..._Args>
1328false_type
1329__has_construct_test(const _Alloc& __a, _Pointer&& __p, _Args&& ...__args);
1330
1331template <class _Alloc, class _Pointer, class ..._Args>
1332struct __has_construct
1333    : integral_constant<bool,
1334        is_same<
1335            decltype(__has_construct_test(declval<_Alloc>(),
1336                                          declval<_Pointer>(),
1337                                          declval<_Args>()...)),
1338            true_type>::value>
1339{
1340};
1341
1342template <class _Alloc, class _Pointer>
1343auto
1344__has_destroy_test(_Alloc&& __a, _Pointer&& __p)
1345    -> decltype(__a.destroy(__p), true_type());
1346
1347template <class _Alloc, class _Pointer>
1348auto
1349__has_destroy_test(const _Alloc& __a, _Pointer&& __p)
1350    -> false_type;
1351
1352template <class _Alloc, class _Pointer>
1353struct __has_destroy
1354    : integral_constant<bool,
1355        is_same<
1356            decltype(__has_destroy_test(declval<_Alloc>(),
1357                                        declval<_Pointer>())),
1358            true_type>::value>
1359{
1360};
1361
1362template <class _Alloc>
1363auto
1364__has_max_size_test(_Alloc&& __a)
1365    -> decltype(__a.max_size(), true_type());
1366
1367template <class _Alloc>
1368auto
1369__has_max_size_test(const volatile _Alloc& __a)
1370    -> false_type;
1371
1372template <class _Alloc>
1373struct __has_max_size
1374    : integral_constant<bool,
1375        is_same<
1376            decltype(__has_max_size_test(declval<_Alloc&>())),
1377            true_type>::value>
1378{
1379};
1380
1381template <class _Alloc>
1382auto
1383__has_select_on_container_copy_construction_test(_Alloc&& __a)
1384    -> decltype(__a.select_on_container_copy_construction(), true_type());
1385
1386template <class _Alloc>
1387auto
1388__has_select_on_container_copy_construction_test(const volatile _Alloc& __a)
1389    -> false_type;
1390
1391template <class _Alloc>
1392struct __has_select_on_container_copy_construction
1393    : integral_constant<bool,
1394        is_same<
1395            decltype(__has_select_on_container_copy_construction_test(declval<_Alloc&>())),
1396            true_type>::value>
1397{
1398};
1399
1400#else  // _LIBCPP_HAS_NO_ADVANCED_SFINAE
1401
1402#ifndef _LIBCPP_HAS_NO_VARIADICS
1403
1404template <class _Alloc, class _Pointer, class ..._Args>
1405struct __has_construct
1406    : false_type
1407{
1408};
1409
1410#else  // _LIBCPP_HAS_NO_VARIADICS
1411
1412template <class _Alloc, class _Pointer, class _Args>
1413struct __has_construct
1414    : false_type
1415{
1416};
1417
1418#endif  // _LIBCPP_HAS_NO_VARIADICS
1419
1420template <class _Alloc, class _Pointer>
1421struct __has_destroy
1422    : false_type
1423{
1424};
1425
1426template <class _Alloc>
1427struct __has_max_size
1428    : true_type
1429{
1430};
1431
1432template <class _Alloc>
1433struct __has_select_on_container_copy_construction
1434    : false_type
1435{
1436};
1437
1438#endif  // _LIBCPP_HAS_NO_ADVANCED_SFINAE
1439
1440template <class _Alloc, class _Ptr, bool = __has_difference_type<_Alloc>::value>
1441struct __alloc_traits_difference_type
1442{
1443    typedef typename pointer_traits<_Ptr>::difference_type type;
1444};
1445
1446template <class _Alloc, class _Ptr>
1447struct __alloc_traits_difference_type<_Alloc, _Ptr, true>
1448{
1449    typedef typename _Alloc::difference_type type;
1450};
1451
1452template <class _Alloc>
1453struct _LIBCPP_TYPE_VIS_ONLY allocator_traits
1454{
1455    typedef _Alloc                              allocator_type;
1456    typedef typename allocator_type::value_type value_type;
1457
1458    typedef typename __pointer_type<value_type, allocator_type>::type pointer;
1459    typedef typename __const_pointer<value_type, pointer, allocator_type>::type const_pointer;
1460    typedef typename __void_pointer<pointer, allocator_type>::type void_pointer;
1461    typedef typename __const_void_pointer<pointer, allocator_type>::type const_void_pointer;
1462
1463    typedef typename __alloc_traits_difference_type<allocator_type, pointer>::type difference_type;
1464    typedef typename __size_type<allocator_type, difference_type>::type size_type;
1465
1466    typedef typename __propagate_on_container_copy_assignment<allocator_type>::type
1467                     propagate_on_container_copy_assignment;
1468    typedef typename __propagate_on_container_move_assignment<allocator_type>::type
1469                     propagate_on_container_move_assignment;
1470    typedef typename __propagate_on_container_swap<allocator_type>::type
1471                     propagate_on_container_swap;
1472    typedef typename __is_always_equal<allocator_type>::type
1473                     is_always_equal;
1474
1475#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1476    template <class _Tp> using rebind_alloc =
1477                  typename __allocator_traits_rebind<allocator_type, _Tp>::type;
1478    template <class _Tp> using rebind_traits = allocator_traits<rebind_alloc<_Tp>>;
1479#else  // _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1480    template <class _Tp> struct rebind_alloc
1481        {typedef typename __allocator_traits_rebind<allocator_type, _Tp>::type other;};
1482    template <class _Tp> struct rebind_traits
1483        {typedef allocator_traits<typename rebind_alloc<_Tp>::other> other;};
1484#endif  // _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1485
1486    _LIBCPP_INLINE_VISIBILITY
1487    static pointer allocate(allocator_type& __a, size_type __n)
1488        {return __a.allocate(__n);}
1489    _LIBCPP_INLINE_VISIBILITY
1490    static pointer allocate(allocator_type& __a, size_type __n, const_void_pointer __hint)
1491        {return allocate(__a, __n, __hint,
1492            __has_allocate_hint<allocator_type, size_type, const_void_pointer>());}
1493
1494    _LIBCPP_INLINE_VISIBILITY
1495    static void deallocate(allocator_type& __a, pointer __p, size_type __n) _NOEXCEPT
1496        {__a.deallocate(__p, __n);}
1497
1498#ifndef _LIBCPP_HAS_NO_VARIADICS
1499    template <class _Tp, class... _Args>
1500        _LIBCPP_INLINE_VISIBILITY
1501        static void construct(allocator_type& __a, _Tp* __p, _Args&&... __args)
1502            {__construct(__has_construct<allocator_type, _Tp*, _Args...>(),
1503                         __a, __p, _VSTD::forward<_Args>(__args)...);}
1504#else  // _LIBCPP_HAS_NO_VARIADICS
1505    template <class _Tp>
1506        _LIBCPP_INLINE_VISIBILITY
1507        static void construct(allocator_type& __a, _Tp* __p)
1508            {
1509                ::new ((void*)__p) _Tp();
1510            }
1511    template <class _Tp, class _A0>
1512        _LIBCPP_INLINE_VISIBILITY
1513        static void construct(allocator_type& __a, _Tp* __p, const _A0& __a0)
1514            {
1515                ::new ((void*)__p) _Tp(__a0);
1516            }
1517    template <class _Tp, class _A0, class _A1>
1518        _LIBCPP_INLINE_VISIBILITY
1519        static void construct(allocator_type& __a, _Tp* __p, const _A0& __a0,
1520                              const _A1& __a1)
1521            {
1522                ::new ((void*)__p) _Tp(__a0, __a1);
1523            }
1524    template <class _Tp, class _A0, class _A1, class _A2>
1525        _LIBCPP_INLINE_VISIBILITY
1526        static void construct(allocator_type& __a, _Tp* __p, const _A0& __a0,
1527                              const _A1& __a1, const _A2& __a2)
1528            {
1529                ::new ((void*)__p) _Tp(__a0, __a1, __a2);
1530            }
1531#endif  // _LIBCPP_HAS_NO_VARIADICS
1532
1533    template <class _Tp>
1534        _LIBCPP_INLINE_VISIBILITY
1535        static void destroy(allocator_type& __a, _Tp* __p)
1536            {__destroy(__has_destroy<allocator_type, _Tp*>(), __a, __p);}
1537
1538    _LIBCPP_INLINE_VISIBILITY
1539    static size_type max_size(const allocator_type& __a) _NOEXCEPT
1540        {return __max_size(__has_max_size<const allocator_type>(), __a);}
1541
1542    _LIBCPP_INLINE_VISIBILITY
1543    static allocator_type
1544        select_on_container_copy_construction(const allocator_type& __a)
1545            {return select_on_container_copy_construction(
1546                __has_select_on_container_copy_construction<const allocator_type>(),
1547                __a);}
1548
1549    template <class _Ptr>
1550        _LIBCPP_INLINE_VISIBILITY
1551        static
1552        void
1553        __construct_forward(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __begin2)
1554        {
1555            for (; __begin1 != __end1; ++__begin1, ++__begin2)
1556                construct(__a, _VSTD::__to_raw_pointer(__begin2), _VSTD::move_if_noexcept(*__begin1));
1557        }
1558
1559    template <class _Tp>
1560        _LIBCPP_INLINE_VISIBILITY
1561        static
1562        typename enable_if
1563        <
1564            (is_same<allocator_type, allocator<_Tp> >::value
1565                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1566             is_trivially_move_constructible<_Tp>::value,
1567            void
1568        >::type
1569        __construct_forward(allocator_type& __a, _Tp* __begin1, _Tp* __end1, _Tp*& __begin2)
1570        {
1571            ptrdiff_t _Np = __end1 - __begin1;
1572            if (_Np > 0)
1573            {
1574                _VSTD::memcpy(__begin2, __begin1, _Np * sizeof(_Tp));
1575                __begin2 += _Np;
1576            }
1577        }
1578
1579    template <class _Iter, class _Ptr>
1580        _LIBCPP_INLINE_VISIBILITY
1581        static
1582        void
1583        __construct_range_forward(allocator_type& __a, _Iter __begin1, _Iter __end1, _Ptr& __begin2)
1584        {
1585            for (; __begin1 != __end1; ++__begin1, (void) ++__begin2)
1586                construct(__a, _VSTD::__to_raw_pointer(__begin2), *__begin1);
1587        }
1588
1589    template <class _Tp>
1590        _LIBCPP_INLINE_VISIBILITY
1591        static
1592        typename enable_if
1593        <
1594            (is_same<allocator_type, allocator<_Tp> >::value
1595                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1596             is_trivially_move_constructible<_Tp>::value,
1597            void
1598        >::type
1599        __construct_range_forward(allocator_type& __a, _Tp* __begin1, _Tp* __end1, _Tp*& __begin2)
1600        {
1601            typedef typename remove_const<_Tp>::type _Vp;
1602            ptrdiff_t _Np = __end1 - __begin1;
1603            if (_Np > 0)
1604            {
1605                _VSTD::memcpy(const_cast<_Vp*>(__begin2), __begin1, _Np * sizeof(_Tp));
1606                __begin2 += _Np;
1607            }
1608        }
1609
1610    template <class _Ptr>
1611        _LIBCPP_INLINE_VISIBILITY
1612        static
1613        void
1614        __construct_backward(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __end2)
1615        {
1616            while (__end1 != __begin1)
1617            {
1618                construct(__a, _VSTD::__to_raw_pointer(__end2-1), _VSTD::move_if_noexcept(*--__end1));
1619                --__end2;
1620            }
1621        }
1622
1623    template <class _Tp>
1624        _LIBCPP_INLINE_VISIBILITY
1625        static
1626        typename enable_if
1627        <
1628            (is_same<allocator_type, allocator<_Tp> >::value
1629                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1630             is_trivially_move_constructible<_Tp>::value,
1631            void
1632        >::type
1633        __construct_backward(allocator_type& __a, _Tp* __begin1, _Tp* __end1, _Tp*& __end2)
1634        {
1635            ptrdiff_t _Np = __end1 - __begin1;
1636            __end2 -= _Np;
1637            if (_Np > 0)
1638                _VSTD::memcpy(__end2, __begin1, _Np * sizeof(_Tp));
1639        }
1640
1641private:
1642
1643    _LIBCPP_INLINE_VISIBILITY
1644    static pointer allocate(allocator_type& __a, size_type __n,
1645        const_void_pointer __hint, true_type)
1646        {return __a.allocate(__n, __hint);}
1647    _LIBCPP_INLINE_VISIBILITY
1648    static pointer allocate(allocator_type& __a, size_type __n,
1649        const_void_pointer, false_type)
1650        {return __a.allocate(__n);}
1651
1652#ifndef _LIBCPP_HAS_NO_VARIADICS
1653    template <class _Tp, class... _Args>
1654        _LIBCPP_INLINE_VISIBILITY
1655        static void __construct(true_type, allocator_type& __a, _Tp* __p, _Args&&... __args)
1656            {__a.construct(__p, _VSTD::forward<_Args>(__args)...);}
1657    template <class _Tp, class... _Args>
1658        _LIBCPP_INLINE_VISIBILITY
1659        static void __construct(false_type, allocator_type&, _Tp* __p, _Args&&... __args)
1660            {
1661                ::new ((void*)__p) _Tp(_VSTD::forward<_Args>(__args)...);
1662            }
1663#endif  // _LIBCPP_HAS_NO_VARIADICS
1664
1665    template <class _Tp>
1666        _LIBCPP_INLINE_VISIBILITY
1667        static void __destroy(true_type, allocator_type& __a, _Tp* __p)
1668            {__a.destroy(__p);}
1669    template <class _Tp>
1670        _LIBCPP_INLINE_VISIBILITY
1671        static void __destroy(false_type, allocator_type&, _Tp* __p)
1672            {
1673                __p->~_Tp();
1674            }
1675
1676    _LIBCPP_INLINE_VISIBILITY
1677    static size_type __max_size(true_type, const allocator_type& __a)
1678            {return __a.max_size();}
1679    _LIBCPP_INLINE_VISIBILITY
1680    static size_type __max_size(false_type, const allocator_type&)
1681            {return numeric_limits<size_type>::max();}
1682
1683    _LIBCPP_INLINE_VISIBILITY
1684    static allocator_type
1685        select_on_container_copy_construction(true_type, const allocator_type& __a)
1686            {return __a.select_on_container_copy_construction();}
1687    _LIBCPP_INLINE_VISIBILITY
1688    static allocator_type
1689        select_on_container_copy_construction(false_type, const allocator_type& __a)
1690            {return __a;}
1691};
1692
1693template <class _Traits, class _Tp>
1694struct __rebind_alloc_helper
1695{
1696#ifndef _LIBCPP_HAS_NO_TEMPLATE_ALIASES
1697    typedef typename _Traits::template rebind_alloc<_Tp>        type;
1698#else
1699    typedef typename _Traits::template rebind_alloc<_Tp>::other type;
1700#endif
1701};
1702
1703// allocator
1704
1705template <class _Tp>
1706class _LIBCPP_TYPE_VIS_ONLY allocator
1707{
1708public:
1709    typedef size_t            size_type;
1710    typedef ptrdiff_t         difference_type;
1711    typedef _Tp*              pointer;
1712    typedef const _Tp*        const_pointer;
1713    typedef _Tp&              reference;
1714    typedef const _Tp&        const_reference;
1715    typedef _Tp               value_type;
1716
1717    typedef true_type propagate_on_container_move_assignment;
1718    typedef true_type is_always_equal;
1719
1720    template <class _Up> struct rebind {typedef allocator<_Up> other;};
1721
1722    _LIBCPP_INLINE_VISIBILITY allocator() _NOEXCEPT {}
1723    template <class _Up> _LIBCPP_INLINE_VISIBILITY allocator(const allocator<_Up>&) _NOEXCEPT {}
1724    _LIBCPP_INLINE_VISIBILITY pointer address(reference __x) const _NOEXCEPT
1725        {return _VSTD::addressof(__x);}
1726    _LIBCPP_INLINE_VISIBILITY const_pointer address(const_reference __x) const _NOEXCEPT
1727        {return _VSTD::addressof(__x);}
1728    _LIBCPP_INLINE_VISIBILITY pointer allocate(size_type __n, allocator<void>::const_pointer = 0)
1729        {return static_cast<pointer>(_VSTD::__allocate(__n * sizeof(_Tp)));}
1730    _LIBCPP_INLINE_VISIBILITY void deallocate(pointer __p, size_type) _NOEXCEPT
1731        {_VSTD::__deallocate((void*)__p);}
1732    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT
1733        {return size_type(~0) / sizeof(_Tp);}
1734#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1735    template <class _Up, class... _Args>
1736        _LIBCPP_INLINE_VISIBILITY
1737        void
1738        construct(_Up* __p, _Args&&... __args)
1739        {
1740            ::new((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
1741        }
1742#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1743        _LIBCPP_INLINE_VISIBILITY
1744        void
1745        construct(pointer __p)
1746        {
1747            ::new((void*)__p) _Tp();
1748        }
1749# if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1750
1751    template <class _A0>
1752        _LIBCPP_INLINE_VISIBILITY
1753        void
1754        construct(pointer __p, _A0& __a0)
1755        {
1756            ::new((void*)__p) _Tp(__a0);
1757        }
1758    template <class _A0>
1759        _LIBCPP_INLINE_VISIBILITY
1760        void
1761        construct(pointer __p, const _A0& __a0)
1762        {
1763            ::new((void*)__p) _Tp(__a0);
1764        }
1765# endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1766    template <class _A0, class _A1>
1767        _LIBCPP_INLINE_VISIBILITY
1768        void
1769        construct(pointer __p, _A0& __a0, _A1& __a1)
1770        {
1771            ::new((void*)__p) _Tp(__a0, __a1);
1772        }
1773    template <class _A0, class _A1>
1774        _LIBCPP_INLINE_VISIBILITY
1775        void
1776        construct(pointer __p, const _A0& __a0, _A1& __a1)
1777        {
1778            ::new((void*)__p) _Tp(__a0, __a1);
1779        }
1780    template <class _A0, class _A1>
1781        _LIBCPP_INLINE_VISIBILITY
1782        void
1783        construct(pointer __p, _A0& __a0, const _A1& __a1)
1784        {
1785            ::new((void*)__p) _Tp(__a0, __a1);
1786        }
1787    template <class _A0, class _A1>
1788        _LIBCPP_INLINE_VISIBILITY
1789        void
1790        construct(pointer __p, const _A0& __a0, const _A1& __a1)
1791        {
1792            ::new((void*)__p) _Tp(__a0, __a1);
1793        }
1794#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1795    _LIBCPP_INLINE_VISIBILITY void destroy(pointer __p) {__p->~_Tp();}
1796};
1797
1798template <class _Tp>
1799class _LIBCPP_TYPE_VIS_ONLY allocator<const _Tp>
1800{
1801public:
1802    typedef size_t            size_type;
1803    typedef ptrdiff_t         difference_type;
1804    typedef const _Tp*        pointer;
1805    typedef const _Tp*        const_pointer;
1806    typedef const _Tp&        reference;
1807    typedef const _Tp&        const_reference;
1808    typedef const _Tp         value_type;
1809
1810    typedef true_type propagate_on_container_move_assignment;
1811    typedef true_type is_always_equal;
1812
1813    template <class _Up> struct rebind {typedef allocator<_Up> other;};
1814
1815    _LIBCPP_INLINE_VISIBILITY allocator() _NOEXCEPT {}
1816    template <class _Up> _LIBCPP_INLINE_VISIBILITY allocator(const allocator<_Up>&) _NOEXCEPT {}
1817    _LIBCPP_INLINE_VISIBILITY const_pointer address(const_reference __x) const _NOEXCEPT
1818        {return _VSTD::addressof(__x);}
1819    _LIBCPP_INLINE_VISIBILITY pointer allocate(size_type __n, allocator<void>::const_pointer = 0)
1820        {return static_cast<pointer>(_VSTD::__allocate(__n * sizeof(_Tp)));}
1821    _LIBCPP_INLINE_VISIBILITY void deallocate(pointer __p, size_type) _NOEXCEPT
1822        {_VSTD::__deallocate((void*)__p);}
1823    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT
1824        {return size_type(~0) / sizeof(_Tp);}
1825#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1826    template <class _Up, class... _Args>
1827        _LIBCPP_INLINE_VISIBILITY
1828        void
1829        construct(_Up* __p, _Args&&... __args)
1830        {
1831            ::new((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
1832        }
1833#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1834        _LIBCPP_INLINE_VISIBILITY
1835        void
1836        construct(pointer __p)
1837        {
1838            ::new((void*)__p) _Tp();
1839        }
1840# if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1841
1842    template <class _A0>
1843        _LIBCPP_INLINE_VISIBILITY
1844        void
1845        construct(pointer __p, _A0& __a0)
1846        {
1847            ::new((void*)__p) _Tp(__a0);
1848        }
1849    template <class _A0>
1850        _LIBCPP_INLINE_VISIBILITY
1851        void
1852        construct(pointer __p, const _A0& __a0)
1853        {
1854            ::new((void*)__p) _Tp(__a0);
1855        }
1856# endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1857    template <class _A0, class _A1>
1858        _LIBCPP_INLINE_VISIBILITY
1859        void
1860        construct(pointer __p, _A0& __a0, _A1& __a1)
1861        {
1862            ::new((void*)__p) _Tp(__a0, __a1);
1863        }
1864    template <class _A0, class _A1>
1865        _LIBCPP_INLINE_VISIBILITY
1866        void
1867        construct(pointer __p, const _A0& __a0, _A1& __a1)
1868        {
1869            ::new((void*)__p) _Tp(__a0, __a1);
1870        }
1871    template <class _A0, class _A1>
1872        _LIBCPP_INLINE_VISIBILITY
1873        void
1874        construct(pointer __p, _A0& __a0, const _A1& __a1)
1875        {
1876            ::new((void*)__p) _Tp(__a0, __a1);
1877        }
1878    template <class _A0, class _A1>
1879        _LIBCPP_INLINE_VISIBILITY
1880        void
1881        construct(pointer __p, const _A0& __a0, const _A1& __a1)
1882        {
1883            ::new((void*)__p) _Tp(__a0, __a1);
1884        }
1885#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1886    _LIBCPP_INLINE_VISIBILITY void destroy(pointer __p) {__p->~_Tp();}
1887};
1888
1889template <class _Tp, class _Up>
1890inline _LIBCPP_INLINE_VISIBILITY
1891bool operator==(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return true;}
1892
1893template <class _Tp, class _Up>
1894inline _LIBCPP_INLINE_VISIBILITY
1895bool operator!=(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return false;}
1896
1897template <class _OutputIterator, class _Tp>
1898class _LIBCPP_TYPE_VIS_ONLY raw_storage_iterator
1899    : public iterator<output_iterator_tag,
1900                      _Tp,                                         // purposefully not C++03
1901                      ptrdiff_t,                                   // purposefully not C++03
1902                      _Tp*,                                        // purposefully not C++03
1903                      raw_storage_iterator<_OutputIterator, _Tp>&> // purposefully not C++03
1904{
1905private:
1906    _OutputIterator __x_;
1907public:
1908    _LIBCPP_INLINE_VISIBILITY explicit raw_storage_iterator(_OutputIterator __x) : __x_(__x) {}
1909    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator*() {return *this;}
1910    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(const _Tp& __element)
1911        {::new(&*__x_) _Tp(__element); return *this;}
1912    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator++() {++__x_; return *this;}
1913    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator  operator++(int)
1914        {raw_storage_iterator __t(*this); ++__x_; return __t;}
1915#if _LIBCPP_STD_VER >= 14
1916    _LIBCPP_INLINE_VISIBILITY _OutputIterator base() const { return __x_; }
1917#endif
1918};
1919
1920template <class _Tp>
1921pair<_Tp*, ptrdiff_t>
1922get_temporary_buffer(ptrdiff_t __n) _NOEXCEPT
1923{
1924    pair<_Tp*, ptrdiff_t> __r(0, 0);
1925    const ptrdiff_t __m = (~ptrdiff_t(0) ^
1926                           ptrdiff_t(ptrdiff_t(1) << (sizeof(ptrdiff_t) * __CHAR_BIT__ - 1)))
1927                           / sizeof(_Tp);
1928    if (__n > __m)
1929        __n = __m;
1930    while (__n > 0)
1931    {
1932        __r.first = static_cast<_Tp*>(::operator new(__n * sizeof(_Tp), nothrow));
1933        if (__r.first)
1934        {
1935            __r.second = __n;
1936            break;
1937        }
1938        __n /= 2;
1939    }
1940    return __r;
1941}
1942
1943template <class _Tp>
1944inline _LIBCPP_INLINE_VISIBILITY
1945void return_temporary_buffer(_Tp* __p) _NOEXCEPT {::operator delete(__p);}
1946
1947template <class _Tp>
1948struct auto_ptr_ref
1949{
1950    _Tp* __ptr_;
1951};
1952
1953template<class _Tp>
1954class _LIBCPP_TYPE_VIS_ONLY auto_ptr
1955{
1956private:
1957    _Tp* __ptr_;
1958public:
1959    typedef _Tp element_type;
1960
1961    _LIBCPP_INLINE_VISIBILITY explicit auto_ptr(_Tp* __p = 0) throw() : __ptr_(__p) {}
1962    _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr& __p) throw() : __ptr_(__p.release()) {}
1963    template<class _Up> _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr<_Up>& __p) throw()
1964        : __ptr_(__p.release()) {}
1965    _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr& __p) throw()
1966        {reset(__p.release()); return *this;}
1967    template<class _Up> _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr<_Up>& __p) throw()
1968        {reset(__p.release()); return *this;}
1969    _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr_ref<_Tp> __p) throw()
1970        {reset(__p.__ptr_); return *this;}
1971    _LIBCPP_INLINE_VISIBILITY ~auto_ptr() throw() {delete __ptr_;}
1972
1973    _LIBCPP_INLINE_VISIBILITY _Tp& operator*() const throw()
1974        {return *__ptr_;}
1975    _LIBCPP_INLINE_VISIBILITY _Tp* operator->() const throw() {return __ptr_;}
1976    _LIBCPP_INLINE_VISIBILITY _Tp* get() const throw() {return __ptr_;}
1977    _LIBCPP_INLINE_VISIBILITY _Tp* release() throw()
1978    {
1979        _Tp* __t = __ptr_;
1980        __ptr_ = 0;
1981        return __t;
1982    }
1983    _LIBCPP_INLINE_VISIBILITY void reset(_Tp* __p = 0) throw()
1984    {
1985        if (__ptr_ != __p)
1986            delete __ptr_;
1987        __ptr_ = __p;
1988    }
1989
1990    _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr_ref<_Tp> __p) throw() : __ptr_(__p.__ptr_) {}
1991    template<class _Up> _LIBCPP_INLINE_VISIBILITY operator auto_ptr_ref<_Up>() throw()
1992        {auto_ptr_ref<_Up> __t; __t.__ptr_ = release(); return __t;}
1993    template<class _Up> _LIBCPP_INLINE_VISIBILITY operator auto_ptr<_Up>() throw()
1994        {return auto_ptr<_Up>(release());}
1995};
1996
1997template <>
1998class _LIBCPP_TYPE_VIS_ONLY auto_ptr<void>
1999{
2000public:
2001    typedef void element_type;
2002};
2003
2004template <class _T1, class _T2, bool = is_same<typename remove_cv<_T1>::type,
2005                                                     typename remove_cv<_T2>::type>::value,
2006                                bool = is_empty<_T1>::value
2007                                       && !__libcpp_is_final<_T1>::value,
2008                                bool = is_empty<_T2>::value
2009                                       && !__libcpp_is_final<_T2>::value
2010         >
2011struct __libcpp_compressed_pair_switch;
2012
2013template <class _T1, class _T2, bool IsSame>
2014struct __libcpp_compressed_pair_switch<_T1, _T2, IsSame, false, false> {enum {value = 0};};
2015
2016template <class _T1, class _T2, bool IsSame>
2017struct __libcpp_compressed_pair_switch<_T1, _T2, IsSame, true, false>  {enum {value = 1};};
2018
2019template <class _T1, class _T2, bool IsSame>
2020struct __libcpp_compressed_pair_switch<_T1, _T2, IsSame, false, true>  {enum {value = 2};};
2021
2022template <class _T1, class _T2>
2023struct __libcpp_compressed_pair_switch<_T1, _T2, false, true, true>    {enum {value = 3};};
2024
2025template <class _T1, class _T2>
2026struct __libcpp_compressed_pair_switch<_T1, _T2, true, true, true>     {enum {value = 1};};
2027
2028template <class _T1, class _T2, unsigned = __libcpp_compressed_pair_switch<_T1, _T2>::value>
2029class __libcpp_compressed_pair_imp;
2030
2031template <class _T1, class _T2>
2032class __libcpp_compressed_pair_imp<_T1, _T2, 0>
2033{
2034private:
2035    _T1 __first_;
2036    _T2 __second_;
2037public:
2038    typedef _T1 _T1_param;
2039    typedef _T2 _T2_param;
2040
2041    typedef typename remove_reference<_T1>::type& _T1_reference;
2042    typedef typename remove_reference<_T2>::type& _T2_reference;
2043
2044    typedef const typename remove_reference<_T1>::type& _T1_const_reference;
2045    typedef const typename remove_reference<_T2>::type& _T2_const_reference;
2046
2047    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() : __first_(), __second_() {}
2048    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2049        : __first_(_VSTD::forward<_T1_param>(__t1)), __second_() {}
2050    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2051        : __first_(), __second_(_VSTD::forward<_T2_param>(__t2)) {}
2052    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2053        : __first_(_VSTD::forward<_T1_param>(__t1)), __second_(_VSTD::forward<_T2_param>(__t2)) {}
2054
2055#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2056
2057    _LIBCPP_INLINE_VISIBILITY
2058    __libcpp_compressed_pair_imp(const __libcpp_compressed_pair_imp& __p)
2059        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2060                   is_nothrow_copy_constructible<_T2>::value)
2061        : __first_(__p.first()),
2062          __second_(__p.second()) {}
2063
2064    _LIBCPP_INLINE_VISIBILITY
2065    __libcpp_compressed_pair_imp& operator=(const __libcpp_compressed_pair_imp& __p)
2066        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2067                   is_nothrow_copy_assignable<_T2>::value)
2068        {
2069            __first_ = __p.first();
2070            __second_ = __p.second();
2071            return *this;
2072        }
2073
2074    _LIBCPP_INLINE_VISIBILITY
2075    __libcpp_compressed_pair_imp(__libcpp_compressed_pair_imp&& __p)
2076        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2077                   is_nothrow_move_constructible<_T2>::value)
2078        : __first_(_VSTD::forward<_T1>(__p.first())),
2079          __second_(_VSTD::forward<_T2>(__p.second())) {}
2080
2081    _LIBCPP_INLINE_VISIBILITY
2082    __libcpp_compressed_pair_imp& operator=(__libcpp_compressed_pair_imp&& __p)
2083        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2084                   is_nothrow_move_assignable<_T2>::value)
2085        {
2086            __first_ = _VSTD::forward<_T1>(__p.first());
2087            __second_ = _VSTD::forward<_T2>(__p.second());
2088            return *this;
2089        }
2090
2091#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2092
2093#ifndef _LIBCPP_HAS_NO_VARIADICS
2094
2095    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2096        _LIBCPP_INLINE_VISIBILITY
2097        __libcpp_compressed_pair_imp(piecewise_construct_t __pc,
2098                                     tuple<_Args1...> __first_args,
2099                                     tuple<_Args2...> __second_args,
2100                                     __tuple_indices<_I1...>,
2101                                     __tuple_indices<_I2...>)
2102            : __first_(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...),
2103              __second_(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...)
2104            {}
2105
2106#endif  // _LIBCPP_HAS_NO_VARIADICS
2107
2108    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return __first_;}
2109    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return __first_;}
2110
2111    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return __second_;}
2112    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return __second_;}
2113
2114    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp& __x)
2115        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2116                   __is_nothrow_swappable<_T2>::value)
2117    {
2118        using _VSTD::swap;
2119        swap(__first_, __x.__first_);
2120        swap(__second_, __x.__second_);
2121    }
2122};
2123
2124template <class _T1, class _T2>
2125class __libcpp_compressed_pair_imp<_T1, _T2, 1>
2126    : private _T1
2127{
2128private:
2129    _T2 __second_;
2130public:
2131    typedef _T1 _T1_param;
2132    typedef _T2 _T2_param;
2133
2134    typedef _T1&                                        _T1_reference;
2135    typedef typename remove_reference<_T2>::type& _T2_reference;
2136
2137    typedef const _T1&                                        _T1_const_reference;
2138    typedef const typename remove_reference<_T2>::type& _T2_const_reference;
2139
2140    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() : __second_() {}
2141    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2142        : _T1(_VSTD::forward<_T1_param>(__t1)), __second_() {}
2143    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2144        : __second_(_VSTD::forward<_T2_param>(__t2)) {}
2145    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2146        : _T1(_VSTD::forward<_T1_param>(__t1)), __second_(_VSTD::forward<_T2_param>(__t2)) {}
2147
2148#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2149
2150    _LIBCPP_INLINE_VISIBILITY
2151    __libcpp_compressed_pair_imp(const __libcpp_compressed_pair_imp& __p)
2152        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2153                   is_nothrow_copy_constructible<_T2>::value)
2154        : _T1(__p.first()), __second_(__p.second()) {}
2155
2156    _LIBCPP_INLINE_VISIBILITY
2157    __libcpp_compressed_pair_imp& operator=(const __libcpp_compressed_pair_imp& __p)
2158        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2159                   is_nothrow_copy_assignable<_T2>::value)
2160        {
2161            _T1::operator=(__p.first());
2162            __second_ = __p.second();
2163            return *this;
2164        }
2165
2166    _LIBCPP_INLINE_VISIBILITY
2167    __libcpp_compressed_pair_imp(__libcpp_compressed_pair_imp&& __p)
2168        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2169                   is_nothrow_move_constructible<_T2>::value)
2170        : _T1(_VSTD::move(__p.first())), __second_(_VSTD::forward<_T2>(__p.second())) {}
2171
2172    _LIBCPP_INLINE_VISIBILITY
2173    __libcpp_compressed_pair_imp& operator=(__libcpp_compressed_pair_imp&& __p)
2174        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2175                   is_nothrow_move_assignable<_T2>::value)
2176        {
2177            _T1::operator=(_VSTD::move(__p.first()));
2178            __second_ = _VSTD::forward<_T2>(__p.second());
2179            return *this;
2180        }
2181
2182#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2183
2184#ifndef _LIBCPP_HAS_NO_VARIADICS
2185
2186    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2187        _LIBCPP_INLINE_VISIBILITY
2188        __libcpp_compressed_pair_imp(piecewise_construct_t __pc,
2189                                     tuple<_Args1...> __first_args,
2190                                     tuple<_Args2...> __second_args,
2191                                     __tuple_indices<_I1...>,
2192                                     __tuple_indices<_I2...>)
2193            : _T1(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...),
2194              __second_(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...)
2195            {}
2196
2197#endif  // _LIBCPP_HAS_NO_VARIADICS
2198
2199    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return *this;}
2200    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return *this;}
2201
2202    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return __second_;}
2203    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return __second_;}
2204
2205    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp& __x)
2206        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2207                   __is_nothrow_swappable<_T2>::value)
2208    {
2209        using _VSTD::swap;
2210        swap(__second_, __x.__second_);
2211    }
2212};
2213
2214template <class _T1, class _T2>
2215class __libcpp_compressed_pair_imp<_T1, _T2, 2>
2216    : private _T2
2217{
2218private:
2219    _T1 __first_;
2220public:
2221    typedef _T1 _T1_param;
2222    typedef _T2 _T2_param;
2223
2224    typedef typename remove_reference<_T1>::type& _T1_reference;
2225    typedef _T2&                                        _T2_reference;
2226
2227    typedef const typename remove_reference<_T1>::type& _T1_const_reference;
2228    typedef const _T2&                                        _T2_const_reference;
2229
2230    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() : __first_() {}
2231    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2232        : __first_(_VSTD::forward<_T1_param>(__t1)) {}
2233    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2234        : _T2(_VSTD::forward<_T2_param>(__t2)), __first_() {}
2235    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2236        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2237                   is_nothrow_move_constructible<_T2>::value)
2238        : _T2(_VSTD::forward<_T2_param>(__t2)), __first_(_VSTD::forward<_T1_param>(__t1)) {}
2239
2240#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2241
2242    _LIBCPP_INLINE_VISIBILITY
2243    __libcpp_compressed_pair_imp(const __libcpp_compressed_pair_imp& __p)
2244        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2245                   is_nothrow_copy_constructible<_T2>::value)
2246        : _T2(__p.second()), __first_(__p.first()) {}
2247
2248    _LIBCPP_INLINE_VISIBILITY
2249    __libcpp_compressed_pair_imp& operator=(const __libcpp_compressed_pair_imp& __p)
2250        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2251                   is_nothrow_copy_assignable<_T2>::value)
2252        {
2253            _T2::operator=(__p.second());
2254            __first_ = __p.first();
2255            return *this;
2256        }
2257
2258    _LIBCPP_INLINE_VISIBILITY
2259    __libcpp_compressed_pair_imp(__libcpp_compressed_pair_imp&& __p)
2260        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2261                   is_nothrow_move_constructible<_T2>::value)
2262        : _T2(_VSTD::forward<_T2>(__p.second())), __first_(_VSTD::move(__p.first())) {}
2263
2264    _LIBCPP_INLINE_VISIBILITY
2265    __libcpp_compressed_pair_imp& operator=(__libcpp_compressed_pair_imp&& __p)
2266        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2267                   is_nothrow_move_assignable<_T2>::value)
2268        {
2269            _T2::operator=(_VSTD::forward<_T2>(__p.second()));
2270            __first_ = _VSTD::move(__p.first());
2271            return *this;
2272        }
2273
2274#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2275
2276#ifndef _LIBCPP_HAS_NO_VARIADICS
2277
2278    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2279        _LIBCPP_INLINE_VISIBILITY
2280        __libcpp_compressed_pair_imp(piecewise_construct_t __pc,
2281                                     tuple<_Args1...> __first_args,
2282                                     tuple<_Args2...> __second_args,
2283                                     __tuple_indices<_I1...>,
2284                                     __tuple_indices<_I2...>)
2285            : _T2(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...),
2286              __first_(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...)
2287
2288            {}
2289
2290#endif  // _LIBCPP_HAS_NO_VARIADICS
2291
2292    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return __first_;}
2293    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return __first_;}
2294
2295    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return *this;}
2296    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return *this;}
2297
2298    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp& __x)
2299        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2300                   __is_nothrow_swappable<_T2>::value)
2301    {
2302        using _VSTD::swap;
2303        swap(__first_, __x.__first_);
2304    }
2305};
2306
2307template <class _T1, class _T2>
2308class __libcpp_compressed_pair_imp<_T1, _T2, 3>
2309    : private _T1,
2310      private _T2
2311{
2312public:
2313    typedef _T1 _T1_param;
2314    typedef _T2 _T2_param;
2315
2316    typedef _T1& _T1_reference;
2317    typedef _T2& _T2_reference;
2318
2319    typedef const _T1& _T1_const_reference;
2320    typedef const _T2& _T2_const_reference;
2321
2322    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() {}
2323    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2324        : _T1(_VSTD::forward<_T1_param>(__t1)) {}
2325    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2326        : _T2(_VSTD::forward<_T2_param>(__t2)) {}
2327    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2328        : _T1(_VSTD::forward<_T1_param>(__t1)), _T2(_VSTD::forward<_T2_param>(__t2)) {}
2329
2330#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2331
2332    _LIBCPP_INLINE_VISIBILITY
2333    __libcpp_compressed_pair_imp(const __libcpp_compressed_pair_imp& __p)
2334        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2335                   is_nothrow_copy_constructible<_T2>::value)
2336        : _T1(__p.first()), _T2(__p.second()) {}
2337
2338    _LIBCPP_INLINE_VISIBILITY
2339    __libcpp_compressed_pair_imp& operator=(const __libcpp_compressed_pair_imp& __p)
2340        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2341                   is_nothrow_copy_assignable<_T2>::value)
2342        {
2343            _T1::operator=(__p.first());
2344            _T2::operator=(__p.second());
2345            return *this;
2346        }
2347
2348    _LIBCPP_INLINE_VISIBILITY
2349    __libcpp_compressed_pair_imp(__libcpp_compressed_pair_imp&& __p)
2350        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2351                   is_nothrow_move_constructible<_T2>::value)
2352        : _T1(_VSTD::move(__p.first())), _T2(_VSTD::move(__p.second())) {}
2353
2354    _LIBCPP_INLINE_VISIBILITY
2355    __libcpp_compressed_pair_imp& operator=(__libcpp_compressed_pair_imp&& __p)
2356        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2357                   is_nothrow_move_assignable<_T2>::value)
2358        {
2359            _T1::operator=(_VSTD::move(__p.first()));
2360            _T2::operator=(_VSTD::move(__p.second()));
2361            return *this;
2362        }
2363
2364#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2365
2366#ifndef _LIBCPP_HAS_NO_VARIADICS
2367
2368    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2369        _LIBCPP_INLINE_VISIBILITY
2370        __libcpp_compressed_pair_imp(piecewise_construct_t __pc,
2371                                     tuple<_Args1...> __first_args,
2372                                     tuple<_Args2...> __second_args,
2373                                     __tuple_indices<_I1...>,
2374                                     __tuple_indices<_I2...>)
2375            : _T1(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...),
2376              _T2(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...)
2377            {}
2378
2379#endif  // _LIBCPP_HAS_NO_VARIADICS
2380
2381    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return *this;}
2382    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return *this;}
2383
2384    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return *this;}
2385    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return *this;}
2386
2387    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp&)
2388        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2389                   __is_nothrow_swappable<_T2>::value)
2390    {
2391    }
2392};
2393
2394template <class _T1, class _T2>
2395class __compressed_pair
2396    : private __libcpp_compressed_pair_imp<_T1, _T2>
2397{
2398    typedef __libcpp_compressed_pair_imp<_T1, _T2> base;
2399public:
2400    typedef typename base::_T1_param _T1_param;
2401    typedef typename base::_T2_param _T2_param;
2402
2403    typedef typename base::_T1_reference _T1_reference;
2404    typedef typename base::_T2_reference _T2_reference;
2405
2406    typedef typename base::_T1_const_reference _T1_const_reference;
2407    typedef typename base::_T2_const_reference _T2_const_reference;
2408
2409    _LIBCPP_INLINE_VISIBILITY __compressed_pair() {}
2410    _LIBCPP_INLINE_VISIBILITY explicit __compressed_pair(_T1_param __t1)
2411        : base(_VSTD::forward<_T1_param>(__t1)) {}
2412    _LIBCPP_INLINE_VISIBILITY explicit __compressed_pair(_T2_param __t2)
2413        : base(_VSTD::forward<_T2_param>(__t2)) {}
2414    _LIBCPP_INLINE_VISIBILITY __compressed_pair(_T1_param __t1, _T2_param __t2)
2415        : base(_VSTD::forward<_T1_param>(__t1), _VSTD::forward<_T2_param>(__t2)) {}
2416
2417#if defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2418
2419    _LIBCPP_INLINE_VISIBILITY
2420    __compressed_pair(const __compressed_pair& __p)
2421        _NOEXCEPT_(is_nothrow_copy_constructible<_T1>::value &&
2422                   is_nothrow_copy_constructible<_T2>::value)
2423        : base(__p) {}
2424
2425    _LIBCPP_INLINE_VISIBILITY
2426    __compressed_pair& operator=(const __compressed_pair& __p)
2427        _NOEXCEPT_(is_nothrow_copy_assignable<_T1>::value &&
2428                   is_nothrow_copy_assignable<_T2>::value)
2429        {
2430            base::operator=(__p);
2431            return *this;
2432        }
2433
2434    _LIBCPP_INLINE_VISIBILITY
2435    __compressed_pair(__compressed_pair&& __p)
2436        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2437                   is_nothrow_move_constructible<_T2>::value)
2438        : base(_VSTD::move(__p)) {}
2439
2440    _LIBCPP_INLINE_VISIBILITY
2441    __compressed_pair& operator=(__compressed_pair&& __p)
2442        _NOEXCEPT_(is_nothrow_move_assignable<_T1>::value &&
2443                   is_nothrow_move_assignable<_T2>::value)
2444        {
2445            base::operator=(_VSTD::move(__p));
2446            return *this;
2447        }
2448
2449#endif  // defined(_LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS) && !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2450
2451#ifndef _LIBCPP_HAS_NO_VARIADICS
2452
2453    template <class... _Args1, class... _Args2>
2454        _LIBCPP_INLINE_VISIBILITY
2455        __compressed_pair(piecewise_construct_t __pc, tuple<_Args1...> __first_args,
2456                                                      tuple<_Args2...> __second_args)
2457            : base(__pc, _VSTD::move(__first_args), _VSTD::move(__second_args),
2458                   typename __make_tuple_indices<sizeof...(_Args1)>::type(),
2459                   typename __make_tuple_indices<sizeof...(_Args2) >::type())
2460            {}
2461
2462#endif  // _LIBCPP_HAS_NO_VARIADICS
2463
2464    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return base::first();}
2465    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return base::first();}
2466
2467    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return base::second();}
2468    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return base::second();}
2469
2470    _LIBCPP_INLINE_VISIBILITY void swap(__compressed_pair& __x)
2471        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2472                   __is_nothrow_swappable<_T2>::value)
2473        {base::swap(__x);}
2474};
2475
2476template <class _T1, class _T2>
2477inline _LIBCPP_INLINE_VISIBILITY
2478void
2479swap(__compressed_pair<_T1, _T2>& __x, __compressed_pair<_T1, _T2>& __y)
2480        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2481                   __is_nothrow_swappable<_T2>::value)
2482    {__x.swap(__y);}
2483
2484// __same_or_less_cv_qualified
2485
2486template <class _Ptr1, class _Ptr2,
2487          bool = is_same<typename remove_cv<typename pointer_traits<_Ptr1>::element_type>::type,
2488                         typename remove_cv<typename pointer_traits<_Ptr2>::element_type>::type
2489                        >::value
2490         >
2491struct __same_or_less_cv_qualified_imp
2492    : is_convertible<_Ptr1, _Ptr2> {};
2493
2494template <class _Ptr1, class _Ptr2>
2495struct __same_or_less_cv_qualified_imp<_Ptr1, _Ptr2, false>
2496    : false_type {};
2497
2498template <class _Ptr1, class _Ptr2, bool = is_pointer<_Ptr1>::value ||
2499                                           is_same<_Ptr1, _Ptr2>::value ||
2500                                           __has_element_type<_Ptr1>::value>
2501struct __same_or_less_cv_qualified
2502    : __same_or_less_cv_qualified_imp<_Ptr1, _Ptr2> {};
2503
2504template <class _Ptr1, class _Ptr2>
2505struct __same_or_less_cv_qualified<_Ptr1, _Ptr2, false>
2506    : false_type {};
2507
2508// default_delete
2509
2510template <class _Tp>
2511struct _LIBCPP_TYPE_VIS_ONLY default_delete
2512{
2513#ifndef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
2514    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT = default;
2515#else
2516    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT {}
2517#endif
2518    template <class _Up>
2519        _LIBCPP_INLINE_VISIBILITY default_delete(const default_delete<_Up>&,
2520             typename enable_if<is_convertible<_Up*, _Tp*>::value>::type* = 0) _NOEXCEPT {}
2521    _LIBCPP_INLINE_VISIBILITY void operator() (_Tp* __ptr) const _NOEXCEPT
2522        {
2523            static_assert(sizeof(_Tp) > 0, "default_delete can not delete incomplete type");
2524            static_assert(!is_void<_Tp>::value, "default_delete can not delete incomplete type");
2525            delete __ptr;
2526        }
2527};
2528
2529template <class _Tp>
2530struct _LIBCPP_TYPE_VIS_ONLY default_delete<_Tp[]>
2531{
2532public:
2533#ifndef _LIBCPP_HAS_NO_DEFAULTED_FUNCTIONS
2534    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT = default;
2535#else
2536    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT {}
2537#endif
2538    template <class _Up>
2539        _LIBCPP_INLINE_VISIBILITY default_delete(const default_delete<_Up[]>&,
2540             typename enable_if<__same_or_less_cv_qualified<_Up*, _Tp*>::value>::type* = 0) _NOEXCEPT {}
2541    template <class _Up>
2542        _LIBCPP_INLINE_VISIBILITY
2543        void operator() (_Up* __ptr,
2544                         typename enable_if<__same_or_less_cv_qualified<_Up*, _Tp*>::value>::type* = 0) const _NOEXCEPT
2545        {
2546            static_assert(sizeof(_Tp) > 0, "default_delete can not delete incomplete type");
2547            static_assert(!is_void<_Tp>::value, "default_delete can not delete incomplete type");
2548            delete [] __ptr;
2549        }
2550};
2551
2552template <class _Tp, class _Dp = default_delete<_Tp> >
2553class _LIBCPP_TYPE_VIS_ONLY unique_ptr
2554{
2555public:
2556    typedef _Tp element_type;
2557    typedef _Dp deleter_type;
2558    typedef typename __pointer_type<_Tp, deleter_type>::type pointer;
2559private:
2560    __compressed_pair<pointer, deleter_type> __ptr_;
2561
2562#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2563    unique_ptr(unique_ptr&);
2564    template <class _Up, class _Ep>
2565        unique_ptr(unique_ptr<_Up, _Ep>&);
2566    unique_ptr& operator=(unique_ptr&);
2567    template <class _Up, class _Ep>
2568        unique_ptr& operator=(unique_ptr<_Up, _Ep>&);
2569#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2570
2571    struct __nat {int __for_bool_;};
2572
2573    typedef       typename remove_reference<deleter_type>::type& _Dp_reference;
2574    typedef const typename remove_reference<deleter_type>::type& _Dp_const_reference;
2575public:
2576    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT
2577        : __ptr_(pointer())
2578        {
2579            static_assert(!is_pointer<deleter_type>::value,
2580                "unique_ptr constructed with null function pointer deleter");
2581        }
2582    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT
2583        : __ptr_(pointer())
2584        {
2585            static_assert(!is_pointer<deleter_type>::value,
2586                "unique_ptr constructed with null function pointer deleter");
2587        }
2588    _LIBCPP_INLINE_VISIBILITY explicit unique_ptr(pointer __p) _NOEXCEPT
2589        : __ptr_(_VSTD::move(__p))
2590        {
2591            static_assert(!is_pointer<deleter_type>::value,
2592                "unique_ptr constructed with null function pointer deleter");
2593        }
2594
2595#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2596    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, typename conditional<
2597                                        is_reference<deleter_type>::value,
2598                                        deleter_type,
2599                                        typename add_lvalue_reference<const deleter_type>::type>::type __d)
2600             _NOEXCEPT
2601        : __ptr_(__p, __d) {}
2602
2603    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, typename remove_reference<deleter_type>::type&& __d)
2604             _NOEXCEPT
2605        : __ptr_(__p, _VSTD::move(__d))
2606        {
2607            static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
2608        }
2609    _LIBCPP_INLINE_VISIBILITY unique_ptr(unique_ptr&& __u) _NOEXCEPT
2610        : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
2611    template <class _Up, class _Ep>
2612        _LIBCPP_INLINE_VISIBILITY
2613        unique_ptr(unique_ptr<_Up, _Ep>&& __u,
2614                   typename enable_if
2615                      <
2616                        !is_array<_Up>::value &&
2617                         is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2618                         is_convertible<_Ep, deleter_type>::value &&
2619                         (
2620                            !is_reference<deleter_type>::value ||
2621                            is_same<deleter_type, _Ep>::value
2622                         ),
2623                         __nat
2624                      >::type = __nat()) _NOEXCEPT
2625            : __ptr_(__u.release(), _VSTD::forward<_Ep>(__u.get_deleter())) {}
2626
2627    template <class _Up>
2628        _LIBCPP_INLINE_VISIBILITY unique_ptr(auto_ptr<_Up>&& __p,
2629                typename enable_if<
2630                                      is_convertible<_Up*, _Tp*>::value &&
2631                                      is_same<_Dp, default_delete<_Tp> >::value,
2632                                      __nat
2633                                  >::type = __nat()) _NOEXCEPT
2634            : __ptr_(__p.release())
2635            {
2636            }
2637
2638        _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT
2639            {
2640                reset(__u.release());
2641                __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
2642                return *this;
2643            }
2644
2645        template <class _Up, class _Ep>
2646            _LIBCPP_INLINE_VISIBILITY
2647            typename enable_if
2648            <
2649                !is_array<_Up>::value &&
2650                is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2651                is_assignable<deleter_type&, _Ep&&>::value,
2652                unique_ptr&
2653            >::type
2654            operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
2655            {
2656                reset(__u.release());
2657                __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2658                return *this;
2659            }
2660#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2661
2662    _LIBCPP_INLINE_VISIBILITY operator __rv<unique_ptr>()
2663    {
2664        return __rv<unique_ptr>(*this);
2665    }
2666
2667    _LIBCPP_INLINE_VISIBILITY unique_ptr(__rv<unique_ptr> __u)
2668        : __ptr_(__u->release(), _VSTD::forward<deleter_type>(__u->get_deleter())) {}
2669
2670    template <class _Up, class _Ep>
2671    _LIBCPP_INLINE_VISIBILITY
2672    typename enable_if<
2673        !is_array<_Up>::value &&
2674        is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2675        is_assignable<deleter_type&, _Ep&>::value,
2676        unique_ptr&
2677    >::type
2678    operator=(unique_ptr<_Up, _Ep> __u)
2679    {
2680        reset(__u.release());
2681        __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2682        return *this;
2683    }
2684
2685    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, deleter_type __d)
2686        : __ptr_(_VSTD::move(__p), _VSTD::move(__d)) {}
2687
2688    template <class _Up>
2689        _LIBCPP_INLINE_VISIBILITY
2690                typename enable_if<
2691                                      is_convertible<_Up*, _Tp*>::value &&
2692                                      is_same<_Dp, default_delete<_Tp> >::value,
2693                                      unique_ptr&
2694                                  >::type
2695        operator=(auto_ptr<_Up> __p)
2696            {reset(__p.release()); return *this;}
2697
2698#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2699    _LIBCPP_INLINE_VISIBILITY ~unique_ptr() {reset();}
2700
2701    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(nullptr_t) _NOEXCEPT
2702    {
2703        reset();
2704        return *this;
2705    }
2706
2707    _LIBCPP_INLINE_VISIBILITY typename add_lvalue_reference<_Tp>::type operator*() const
2708        {return *__ptr_.first();}
2709    _LIBCPP_INLINE_VISIBILITY pointer operator->() const _NOEXCEPT {return __ptr_.first();}
2710    _LIBCPP_INLINE_VISIBILITY pointer get() const _NOEXCEPT {return __ptr_.first();}
2711    _LIBCPP_INLINE_VISIBILITY       _Dp_reference get_deleter() _NOEXCEPT
2712        {return __ptr_.second();}
2713    _LIBCPP_INLINE_VISIBILITY _Dp_const_reference get_deleter() const _NOEXCEPT
2714        {return __ptr_.second();}
2715    _LIBCPP_INLINE_VISIBILITY
2716        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT
2717        {return __ptr_.first() != nullptr;}
2718
2719    _LIBCPP_INLINE_VISIBILITY pointer release() _NOEXCEPT
2720    {
2721        pointer __t = __ptr_.first();
2722        __ptr_.first() = pointer();
2723        return __t;
2724    }
2725
2726    _LIBCPP_INLINE_VISIBILITY void reset(pointer __p = pointer()) _NOEXCEPT
2727    {
2728        pointer __tmp = __ptr_.first();
2729        __ptr_.first() = __p;
2730        if (__tmp)
2731            __ptr_.second()(__tmp);
2732    }
2733
2734    _LIBCPP_INLINE_VISIBILITY void swap(unique_ptr& __u) _NOEXCEPT
2735        {__ptr_.swap(__u.__ptr_);}
2736};
2737
2738template <class _Tp, class _Dp>
2739class _LIBCPP_TYPE_VIS_ONLY unique_ptr<_Tp[], _Dp>
2740{
2741public:
2742    typedef _Tp element_type;
2743    typedef _Dp deleter_type;
2744    typedef typename __pointer_type<_Tp, deleter_type>::type pointer;
2745private:
2746    __compressed_pair<pointer, deleter_type> __ptr_;
2747
2748#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2749    unique_ptr(unique_ptr&);
2750    template <class _Up>
2751        unique_ptr(unique_ptr<_Up>&);
2752    unique_ptr& operator=(unique_ptr&);
2753    template <class _Up>
2754        unique_ptr& operator=(unique_ptr<_Up>&);
2755#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2756
2757    struct __nat {int __for_bool_;};
2758
2759    typedef       typename remove_reference<deleter_type>::type& _Dp_reference;
2760    typedef const typename remove_reference<deleter_type>::type& _Dp_const_reference;
2761public:
2762    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT
2763        : __ptr_(pointer())
2764        {
2765            static_assert(!is_pointer<deleter_type>::value,
2766                "unique_ptr constructed with null function pointer deleter");
2767        }
2768    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT
2769        : __ptr_(pointer())
2770        {
2771            static_assert(!is_pointer<deleter_type>::value,
2772                "unique_ptr constructed with null function pointer deleter");
2773        }
2774#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2775    template <class _Pp>
2776    _LIBCPP_INLINE_VISIBILITY explicit unique_ptr(_Pp __p,
2777            typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, __nat>::type = __nat()) _NOEXCEPT
2778        : __ptr_(__p)
2779        {
2780            static_assert(!is_pointer<deleter_type>::value,
2781                "unique_ptr constructed with null function pointer deleter");
2782        }
2783
2784    template <class _Pp>
2785    _LIBCPP_INLINE_VISIBILITY unique_ptr(_Pp __p, typename conditional<
2786                                       is_reference<deleter_type>::value,
2787                                       deleter_type,
2788                                       typename add_lvalue_reference<const deleter_type>::type>::type __d,
2789                                       typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, __nat>::type = __nat())
2790             _NOEXCEPT
2791        : __ptr_(__p, __d) {}
2792
2793    _LIBCPP_INLINE_VISIBILITY unique_ptr(nullptr_t, typename conditional<
2794                                       is_reference<deleter_type>::value,
2795                                       deleter_type,
2796                                       typename add_lvalue_reference<const deleter_type>::type>::type __d)
2797             _NOEXCEPT
2798        : __ptr_(pointer(), __d) {}
2799
2800    template <class _Pp>
2801    _LIBCPP_INLINE_VISIBILITY unique_ptr(_Pp __p,
2802                                         typename remove_reference<deleter_type>::type&& __d,
2803                                         typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, __nat>::type = __nat())
2804             _NOEXCEPT
2805        : __ptr_(__p, _VSTD::move(__d))
2806        {
2807            static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
2808        }
2809
2810    _LIBCPP_INLINE_VISIBILITY unique_ptr(nullptr_t, typename remove_reference<deleter_type>::type&& __d)
2811             _NOEXCEPT
2812        : __ptr_(pointer(), _VSTD::move(__d))
2813        {
2814            static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
2815        }
2816
2817    _LIBCPP_INLINE_VISIBILITY unique_ptr(unique_ptr&& __u) _NOEXCEPT
2818        : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
2819
2820    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT
2821        {
2822            reset(__u.release());
2823            __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
2824            return *this;
2825        }
2826
2827    template <class _Up, class _Ep>
2828        _LIBCPP_INLINE_VISIBILITY
2829        unique_ptr(unique_ptr<_Up, _Ep>&& __u,
2830                   typename enable_if
2831                            <
2832                                is_array<_Up>::value &&
2833                                __same_or_less_cv_qualified<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value
2834                                && is_convertible<_Ep, deleter_type>::value &&
2835                                (
2836                                    !is_reference<deleter_type>::value ||
2837                                    is_same<deleter_type, _Ep>::value
2838                                ),
2839                                __nat
2840                            >::type = __nat()
2841                  ) _NOEXCEPT
2842        : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
2843
2844
2845        template <class _Up, class _Ep>
2846            _LIBCPP_INLINE_VISIBILITY
2847            typename enable_if
2848            <
2849                is_array<_Up>::value &&
2850                __same_or_less_cv_qualified<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2851                is_assignable<deleter_type&, _Ep&&>::value,
2852                unique_ptr&
2853            >::type
2854            operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
2855            {
2856                reset(__u.release());
2857                __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2858                return *this;
2859            }
2860#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2861
2862    _LIBCPP_INLINE_VISIBILITY explicit unique_ptr(pointer __p)
2863        : __ptr_(__p)
2864        {
2865            static_assert(!is_pointer<deleter_type>::value,
2866                "unique_ptr constructed with null function pointer deleter");
2867        }
2868
2869    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, deleter_type __d)
2870        : __ptr_(__p, _VSTD::forward<deleter_type>(__d)) {}
2871
2872    _LIBCPP_INLINE_VISIBILITY unique_ptr(nullptr_t, deleter_type __d)
2873        : __ptr_(pointer(), _VSTD::forward<deleter_type>(__d)) {}
2874
2875    _LIBCPP_INLINE_VISIBILITY operator __rv<unique_ptr>()
2876    {
2877        return __rv<unique_ptr>(*this);
2878    }
2879
2880    _LIBCPP_INLINE_VISIBILITY unique_ptr(__rv<unique_ptr> __u)
2881        : __ptr_(__u->release(), _VSTD::forward<deleter_type>(__u->get_deleter())) {}
2882
2883    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(__rv<unique_ptr> __u)
2884    {
2885        reset(__u->release());
2886        __ptr_.second() = _VSTD::forward<deleter_type>(__u->get_deleter());
2887        return *this;
2888    }
2889
2890#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2891    _LIBCPP_INLINE_VISIBILITY ~unique_ptr() {reset();}
2892
2893    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(nullptr_t) _NOEXCEPT
2894    {
2895        reset();
2896        return *this;
2897    }
2898
2899    _LIBCPP_INLINE_VISIBILITY typename add_lvalue_reference<_Tp>::type operator[](size_t __i) const
2900        {return __ptr_.first()[__i];}
2901    _LIBCPP_INLINE_VISIBILITY pointer get() const _NOEXCEPT {return __ptr_.first();}
2902    _LIBCPP_INLINE_VISIBILITY       _Dp_reference get_deleter() _NOEXCEPT
2903        {return __ptr_.second();}
2904    _LIBCPP_INLINE_VISIBILITY _Dp_const_reference get_deleter() const _NOEXCEPT
2905        {return __ptr_.second();}
2906    _LIBCPP_INLINE_VISIBILITY
2907        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT
2908        {return __ptr_.first() != nullptr;}
2909
2910    _LIBCPP_INLINE_VISIBILITY pointer release() _NOEXCEPT
2911    {
2912        pointer __t = __ptr_.first();
2913        __ptr_.first() = pointer();
2914        return __t;
2915    }
2916
2917#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2918    template <class _Pp>
2919    _LIBCPP_INLINE_VISIBILITY
2920    typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, void>::type
2921    reset(_Pp __p) _NOEXCEPT
2922    {
2923        pointer __tmp = __ptr_.first();
2924        __ptr_.first() = __p;
2925        if (__tmp)
2926            __ptr_.second()(__tmp);
2927    }
2928    _LIBCPP_INLINE_VISIBILITY void reset(nullptr_t) _NOEXCEPT
2929    {
2930        pointer __tmp = __ptr_.first();
2931        __ptr_.first() = nullptr;
2932        if (__tmp)
2933            __ptr_.second()(__tmp);
2934    }
2935    _LIBCPP_INLINE_VISIBILITY void reset() _NOEXCEPT
2936    {
2937        pointer __tmp = __ptr_.first();
2938        __ptr_.first() = nullptr;
2939        if (__tmp)
2940            __ptr_.second()(__tmp);
2941    }
2942#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2943    _LIBCPP_INLINE_VISIBILITY void reset(pointer __p = pointer())
2944    {
2945        pointer __tmp = __ptr_.first();
2946        __ptr_.first() = __p;
2947        if (__tmp)
2948            __ptr_.second()(__tmp);
2949    }
2950#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2951
2952    _LIBCPP_INLINE_VISIBILITY void swap(unique_ptr& __u) {__ptr_.swap(__u.__ptr_);}
2953private:
2954
2955#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2956    template <class _Up>
2957        explicit unique_ptr(_Up);
2958    template <class _Up>
2959        unique_ptr(_Up __u,
2960                   typename conditional<
2961                                       is_reference<deleter_type>::value,
2962                                       deleter_type,
2963                                       typename add_lvalue_reference<const deleter_type>::type>::type,
2964                   typename enable_if
2965                      <
2966                         is_convertible<_Up, pointer>::value,
2967                         __nat
2968                      >::type = __nat());
2969#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2970};
2971
2972template <class _Tp, class _Dp>
2973inline _LIBCPP_INLINE_VISIBILITY
2974void
2975swap(unique_ptr<_Tp, _Dp>& __x, unique_ptr<_Tp, _Dp>& __y) _NOEXCEPT {__x.swap(__y);}
2976
2977template <class _T1, class _D1, class _T2, class _D2>
2978inline _LIBCPP_INLINE_VISIBILITY
2979bool
2980operator==(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __x.get() == __y.get();}
2981
2982template <class _T1, class _D1, class _T2, class _D2>
2983inline _LIBCPP_INLINE_VISIBILITY
2984bool
2985operator!=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x == __y);}
2986
2987template <class _T1, class _D1, class _T2, class _D2>
2988inline _LIBCPP_INLINE_VISIBILITY
2989bool
2990operator< (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y)
2991{
2992    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
2993    typedef typename unique_ptr<_T2, _D2>::pointer _P2;
2994    typedef typename common_type<_P1, _P2>::type _Vp;
2995    return less<_Vp>()(__x.get(), __y.get());
2996}
2997
2998template <class _T1, class _D1, class _T2, class _D2>
2999inline _LIBCPP_INLINE_VISIBILITY
3000bool
3001operator> (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __y < __x;}
3002
3003template <class _T1, class _D1, class _T2, class _D2>
3004inline _LIBCPP_INLINE_VISIBILITY
3005bool
3006operator<=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__y < __x);}
3007
3008template <class _T1, class _D1, class _T2, class _D2>
3009inline _LIBCPP_INLINE_VISIBILITY
3010bool
3011operator>=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x < __y);}
3012
3013template <class _T1, class _D1>
3014inline _LIBCPP_INLINE_VISIBILITY
3015bool
3016operator==(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
3017{
3018    return !__x;
3019}
3020
3021template <class _T1, class _D1>
3022inline _LIBCPP_INLINE_VISIBILITY
3023bool
3024operator==(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
3025{
3026    return !__x;
3027}
3028
3029template <class _T1, class _D1>
3030inline _LIBCPP_INLINE_VISIBILITY
3031bool
3032operator!=(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
3033{
3034    return static_cast<bool>(__x);
3035}
3036
3037template <class _T1, class _D1>
3038inline _LIBCPP_INLINE_VISIBILITY
3039bool
3040operator!=(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
3041{
3042    return static_cast<bool>(__x);
3043}
3044
3045template <class _T1, class _D1>
3046inline _LIBCPP_INLINE_VISIBILITY
3047bool
3048operator<(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3049{
3050    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
3051    return less<_P1>()(__x.get(), nullptr);
3052}
3053
3054template <class _T1, class _D1>
3055inline _LIBCPP_INLINE_VISIBILITY
3056bool
3057operator<(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3058{
3059    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
3060    return less<_P1>()(nullptr, __x.get());
3061}
3062
3063template <class _T1, class _D1>
3064inline _LIBCPP_INLINE_VISIBILITY
3065bool
3066operator>(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3067{
3068    return nullptr < __x;
3069}
3070
3071template <class _T1, class _D1>
3072inline _LIBCPP_INLINE_VISIBILITY
3073bool
3074operator>(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3075{
3076    return __x < nullptr;
3077}
3078
3079template <class _T1, class _D1>
3080inline _LIBCPP_INLINE_VISIBILITY
3081bool
3082operator<=(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3083{
3084    return !(nullptr < __x);
3085}
3086
3087template <class _T1, class _D1>
3088inline _LIBCPP_INLINE_VISIBILITY
3089bool
3090operator<=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3091{
3092    return !(__x < nullptr);
3093}
3094
3095template <class _T1, class _D1>
3096inline _LIBCPP_INLINE_VISIBILITY
3097bool
3098operator>=(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3099{
3100    return !(__x < nullptr);
3101}
3102
3103template <class _T1, class _D1>
3104inline _LIBCPP_INLINE_VISIBILITY
3105bool
3106operator>=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3107{
3108    return !(nullptr < __x);
3109}
3110
3111#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3112
3113template <class _Tp, class _Dp>
3114inline _LIBCPP_INLINE_VISIBILITY
3115unique_ptr<_Tp, _Dp>
3116move(unique_ptr<_Tp, _Dp>& __t)
3117{
3118    return unique_ptr<_Tp, _Dp>(__rv<unique_ptr<_Tp, _Dp> >(__t));
3119}
3120
3121#endif
3122
3123#if _LIBCPP_STD_VER > 11
3124
3125template<class _Tp>
3126struct __unique_if
3127{
3128    typedef unique_ptr<_Tp> __unique_single;
3129};
3130
3131template<class _Tp>
3132struct __unique_if<_Tp[]>
3133{
3134    typedef unique_ptr<_Tp[]> __unique_array_unknown_bound;
3135};
3136
3137template<class _Tp, size_t _Np>
3138struct __unique_if<_Tp[_Np]>
3139{
3140    typedef void __unique_array_known_bound;
3141};
3142
3143template<class _Tp, class... _Args>
3144inline _LIBCPP_INLINE_VISIBILITY
3145typename __unique_if<_Tp>::__unique_single
3146make_unique(_Args&&... __args)
3147{
3148    return unique_ptr<_Tp>(new _Tp(_VSTD::forward<_Args>(__args)...));
3149}
3150
3151template<class _Tp>
3152inline _LIBCPP_INLINE_VISIBILITY
3153typename __unique_if<_Tp>::__unique_array_unknown_bound
3154make_unique(size_t __n)
3155{
3156    typedef typename remove_extent<_Tp>::type _Up;
3157    return unique_ptr<_Tp>(new _Up[__n]());
3158}
3159
3160template<class _Tp, class... _Args>
3161    typename __unique_if<_Tp>::__unique_array_known_bound
3162    make_unique(_Args&&...) = delete;
3163
3164#endif  // _LIBCPP_STD_VER > 11
3165
3166template <class _Tp> struct hash;
3167
3168template <class _Size>
3169inline _LIBCPP_INLINE_VISIBILITY
3170_Size
3171__loadword(const void* __p)
3172{
3173    _Size __r;
3174    std::memcpy(&__r, __p, sizeof(__r));
3175    return __r;
3176}
3177
3178// We use murmur2 when size_t is 32 bits, and cityhash64 when size_t
3179// is 64 bits.  This is because cityhash64 uses 64bit x 64bit
3180// multiplication, which can be very slow on 32-bit systems.
3181template <class _Size, size_t = sizeof(_Size)*__CHAR_BIT__>
3182struct __murmur2_or_cityhash;
3183
3184template <class _Size>
3185struct __murmur2_or_cityhash<_Size, 32>
3186{
3187    _Size operator()(const void* __key, _Size __len);
3188};
3189
3190// murmur2
3191template <class _Size>
3192_Size
3193__murmur2_or_cityhash<_Size, 32>::operator()(const void* __key, _Size __len)
3194{
3195    const _Size __m = 0x5bd1e995;
3196    const _Size __r = 24;
3197    _Size __h = __len;
3198    const unsigned char* __data = static_cast<const unsigned char*>(__key);
3199    for (; __len >= 4; __data += 4, __len -= 4)
3200    {
3201        _Size __k = __loadword<_Size>(__data);
3202        __k *= __m;
3203        __k ^= __k >> __r;
3204        __k *= __m;
3205        __h *= __m;
3206        __h ^= __k;
3207    }
3208    switch (__len)
3209    {
3210    case 3:
3211        __h ^= __data[2] << 16;
3212    case 2:
3213        __h ^= __data[1] << 8;
3214    case 1:
3215        __h ^= __data[0];
3216        __h *= __m;
3217    }
3218    __h ^= __h >> 13;
3219    __h *= __m;
3220    __h ^= __h >> 15;
3221    return __h;
3222}
3223
3224template <class _Size>
3225struct __murmur2_or_cityhash<_Size, 64>
3226{
3227    _Size operator()(const void* __key, _Size __len);
3228
3229 private:
3230  // Some primes between 2^63 and 2^64.
3231  static const _Size __k0 = 0xc3a5c85c97cb3127ULL;
3232  static const _Size __k1 = 0xb492b66fbe98f273ULL;
3233  static const _Size __k2 = 0x9ae16a3b2f90404fULL;
3234  static const _Size __k3 = 0xc949d7c7509e6557ULL;
3235
3236  static _Size __rotate(_Size __val, int __shift) {
3237    return __shift == 0 ? __val : ((__val >> __shift) | (__val << (64 - __shift)));
3238  }
3239
3240  static _Size __rotate_by_at_least_1(_Size __val, int __shift) {
3241    return (__val >> __shift) | (__val << (64 - __shift));
3242  }
3243
3244  static _Size __shift_mix(_Size __val) {
3245    return __val ^ (__val >> 47);
3246  }
3247
3248  static _Size __hash_len_16(_Size __u, _Size __v) {
3249    const _Size __mul = 0x9ddfea08eb382d69ULL;
3250    _Size __a = (__u ^ __v) * __mul;
3251    __a ^= (__a >> 47);
3252    _Size __b = (__v ^ __a) * __mul;
3253    __b ^= (__b >> 47);
3254    __b *= __mul;
3255    return __b;
3256  }
3257
3258  static _Size __hash_len_0_to_16(const char* __s, _Size __len) {
3259    if (__len > 8) {
3260      const _Size __a = __loadword<_Size>(__s);
3261      const _Size __b = __loadword<_Size>(__s + __len - 8);
3262      return __hash_len_16(__a, __rotate_by_at_least_1(__b + __len, __len)) ^ __b;
3263    }
3264    if (__len >= 4) {
3265      const uint32_t __a = __loadword<uint32_t>(__s);
3266      const uint32_t __b = __loadword<uint32_t>(__s + __len - 4);
3267      return __hash_len_16(__len + (__a << 3), __b);
3268    }
3269    if (__len > 0) {
3270      const unsigned char __a = __s[0];
3271      const unsigned char __b = __s[__len >> 1];
3272      const unsigned char __c = __s[__len - 1];
3273      const uint32_t __y = static_cast<uint32_t>(__a) +
3274                           (static_cast<uint32_t>(__b) << 8);
3275      const uint32_t __z = __len + (static_cast<uint32_t>(__c) << 2);
3276      return __shift_mix(__y * __k2 ^ __z * __k3) * __k2;
3277    }
3278    return __k2;
3279  }
3280
3281  static _Size __hash_len_17_to_32(const char *__s, _Size __len) {
3282    const _Size __a = __loadword<_Size>(__s) * __k1;
3283    const _Size __b = __loadword<_Size>(__s + 8);
3284    const _Size __c = __loadword<_Size>(__s + __len - 8) * __k2;
3285    const _Size __d = __loadword<_Size>(__s + __len - 16) * __k0;
3286    return __hash_len_16(__rotate(__a - __b, 43) + __rotate(__c, 30) + __d,
3287                         __a + __rotate(__b ^ __k3, 20) - __c + __len);
3288  }
3289
3290  // Return a 16-byte hash for 48 bytes.  Quick and dirty.
3291  // Callers do best to use "random-looking" values for a and b.
3292  static pair<_Size, _Size> __weak_hash_len_32_with_seeds(
3293      _Size __w, _Size __x, _Size __y, _Size __z, _Size __a, _Size __b) {
3294    __a += __w;
3295    __b = __rotate(__b + __a + __z, 21);
3296    const _Size __c = __a;
3297    __a += __x;
3298    __a += __y;
3299    __b += __rotate(__a, 44);
3300    return pair<_Size, _Size>(__a + __z, __b + __c);
3301  }
3302
3303  // Return a 16-byte hash for s[0] ... s[31], a, and b.  Quick and dirty.
3304  static pair<_Size, _Size> __weak_hash_len_32_with_seeds(
3305      const char* __s, _Size __a, _Size __b) {
3306    return __weak_hash_len_32_with_seeds(__loadword<_Size>(__s),
3307                                         __loadword<_Size>(__s + 8),
3308                                         __loadword<_Size>(__s + 16),
3309                                         __loadword<_Size>(__s + 24),
3310                                         __a,
3311                                         __b);
3312  }
3313
3314  // Return an 8-byte hash for 33 to 64 bytes.
3315  static _Size __hash_len_33_to_64(const char *__s, size_t __len) {
3316    _Size __z = __loadword<_Size>(__s + 24);
3317    _Size __a = __loadword<_Size>(__s) +
3318                (__len + __loadword<_Size>(__s + __len - 16)) * __k0;
3319    _Size __b = __rotate(__a + __z, 52);
3320    _Size __c = __rotate(__a, 37);
3321    __a += __loadword<_Size>(__s + 8);
3322    __c += __rotate(__a, 7);
3323    __a += __loadword<_Size>(__s + 16);
3324    _Size __vf = __a + __z;
3325    _Size __vs = __b + __rotate(__a, 31) + __c;
3326    __a = __loadword<_Size>(__s + 16) + __loadword<_Size>(__s + __len - 32);
3327    __z += __loadword<_Size>(__s + __len - 8);
3328    __b = __rotate(__a + __z, 52);
3329    __c = __rotate(__a, 37);
3330    __a += __loadword<_Size>(__s + __len - 24);
3331    __c += __rotate(__a, 7);
3332    __a += __loadword<_Size>(__s + __len - 16);
3333    _Size __wf = __a + __z;
3334    _Size __ws = __b + __rotate(__a, 31) + __c;
3335    _Size __r = __shift_mix((__vf + __ws) * __k2 + (__wf + __vs) * __k0);
3336    return __shift_mix(__r * __k0 + __vs) * __k2;
3337  }
3338};
3339
3340// cityhash64
3341template <class _Size>
3342_Size
3343__murmur2_or_cityhash<_Size, 64>::operator()(const void* __key, _Size __len)
3344{
3345  const char* __s = static_cast<const char*>(__key);
3346  if (__len <= 32) {
3347    if (__len <= 16) {
3348      return __hash_len_0_to_16(__s, __len);
3349    } else {
3350      return __hash_len_17_to_32(__s, __len);
3351    }
3352  } else if (__len <= 64) {
3353    return __hash_len_33_to_64(__s, __len);
3354  }
3355
3356  // For strings over 64 bytes we hash the end first, and then as we
3357  // loop we keep 56 bytes of state: v, w, x, y, and z.
3358  _Size __x = __loadword<_Size>(__s + __len - 40);
3359  _Size __y = __loadword<_Size>(__s + __len - 16) +
3360              __loadword<_Size>(__s + __len - 56);
3361  _Size __z = __hash_len_16(__loadword<_Size>(__s + __len - 48) + __len,
3362                          __loadword<_Size>(__s + __len - 24));
3363  pair<_Size, _Size> __v = __weak_hash_len_32_with_seeds(__s + __len - 64, __len, __z);
3364  pair<_Size, _Size> __w = __weak_hash_len_32_with_seeds(__s + __len - 32, __y + __k1, __x);
3365  __x = __x * __k1 + __loadword<_Size>(__s);
3366
3367  // Decrease len to the nearest multiple of 64, and operate on 64-byte chunks.
3368  __len = (__len - 1) & ~static_cast<_Size>(63);
3369  do {
3370    __x = __rotate(__x + __y + __v.first + __loadword<_Size>(__s + 8), 37) * __k1;
3371    __y = __rotate(__y + __v.second + __loadword<_Size>(__s + 48), 42) * __k1;
3372    __x ^= __w.second;
3373    __y += __v.first + __loadword<_Size>(__s + 40);
3374    __z = __rotate(__z + __w.first, 33) * __k1;
3375    __v = __weak_hash_len_32_with_seeds(__s, __v.second * __k1, __x + __w.first);
3376    __w = __weak_hash_len_32_with_seeds(__s + 32, __z + __w.second,
3377                                        __y + __loadword<_Size>(__s + 16));
3378    std::swap(__z, __x);
3379    __s += 64;
3380    __len -= 64;
3381  } while (__len != 0);
3382  return __hash_len_16(
3383      __hash_len_16(__v.first, __w.first) + __shift_mix(__y) * __k1 + __z,
3384      __hash_len_16(__v.second, __w.second) + __x);
3385}
3386
3387template <class _Tp, size_t = sizeof(_Tp) / sizeof(size_t)>
3388struct __scalar_hash;
3389
3390template <class _Tp>
3391struct __scalar_hash<_Tp, 0>
3392    : public unary_function<_Tp, size_t>
3393{
3394    _LIBCPP_INLINE_VISIBILITY
3395    size_t operator()(_Tp __v) const _NOEXCEPT
3396    {
3397        union
3398        {
3399            _Tp    __t;
3400            size_t __a;
3401        } __u;
3402        __u.__a = 0;
3403        __u.__t = __v;
3404        return __u.__a;
3405    }
3406};
3407
3408template <class _Tp>
3409struct __scalar_hash<_Tp, 1>
3410    : public unary_function<_Tp, size_t>
3411{
3412    _LIBCPP_INLINE_VISIBILITY
3413    size_t operator()(_Tp __v) const _NOEXCEPT
3414    {
3415        union
3416        {
3417            _Tp    __t;
3418            size_t __a;
3419        } __u;
3420        __u.__t = __v;
3421        return __u.__a;
3422    }
3423};
3424
3425template <class _Tp>
3426struct __scalar_hash<_Tp, 2>
3427    : public unary_function<_Tp, size_t>
3428{
3429    _LIBCPP_INLINE_VISIBILITY
3430    size_t operator()(_Tp __v) const _NOEXCEPT
3431    {
3432        union
3433        {
3434            _Tp __t;
3435            struct
3436            {
3437                size_t __a;
3438                size_t __b;
3439            } __s;
3440        } __u;
3441        __u.__t = __v;
3442        return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
3443    }
3444};
3445
3446template <class _Tp>
3447struct __scalar_hash<_Tp, 3>
3448    : public unary_function<_Tp, size_t>
3449{
3450    _LIBCPP_INLINE_VISIBILITY
3451    size_t operator()(_Tp __v) const _NOEXCEPT
3452    {
3453        union
3454        {
3455            _Tp __t;
3456            struct
3457            {
3458                size_t __a;
3459                size_t __b;
3460                size_t __c;
3461            } __s;
3462        } __u;
3463        __u.__t = __v;
3464        return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
3465    }
3466};
3467
3468template <class _Tp>
3469struct __scalar_hash<_Tp, 4>
3470    : public unary_function<_Tp, size_t>
3471{
3472    _LIBCPP_INLINE_VISIBILITY
3473    size_t operator()(_Tp __v) const _NOEXCEPT
3474    {
3475        union
3476        {
3477            _Tp __t;
3478            struct
3479            {
3480                size_t __a;
3481                size_t __b;
3482                size_t __c;
3483                size_t __d;
3484            } __s;
3485        } __u;
3486        __u.__t = __v;
3487        return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
3488    }
3489};
3490
3491template<class _Tp>
3492struct _LIBCPP_TYPE_VIS_ONLY hash<_Tp*>
3493    : public unary_function<_Tp*, size_t>
3494{
3495    _LIBCPP_INLINE_VISIBILITY
3496    size_t operator()(_Tp* __v) const _NOEXCEPT
3497    {
3498        union
3499        {
3500            _Tp* __t;
3501            size_t __a;
3502        } __u;
3503        __u.__t = __v;
3504        return __murmur2_or_cityhash<size_t>()(&__u, sizeof(__u));
3505    }
3506};
3507
3508template <class _Tp, class _Dp>
3509struct _LIBCPP_TYPE_VIS_ONLY hash<unique_ptr<_Tp, _Dp> >
3510{
3511    typedef unique_ptr<_Tp, _Dp> argument_type;
3512    typedef size_t               result_type;
3513    _LIBCPP_INLINE_VISIBILITY
3514    result_type operator()(const argument_type& __ptr) const _NOEXCEPT
3515    {
3516        typedef typename argument_type::pointer pointer;
3517        return hash<pointer>()(__ptr.get());
3518    }
3519};
3520
3521struct __destruct_n
3522{
3523private:
3524    size_t size;
3525
3526    template <class _Tp>
3527    _LIBCPP_INLINE_VISIBILITY void __process(_Tp* __p, false_type) _NOEXCEPT
3528        {for (size_t __i = 0; __i < size; ++__i, ++__p) __p->~_Tp();}
3529
3530    template <class _Tp>
3531    _LIBCPP_INLINE_VISIBILITY void __process(_Tp*, true_type) _NOEXCEPT
3532        {}
3533
3534    _LIBCPP_INLINE_VISIBILITY void __incr(false_type) _NOEXCEPT
3535        {++size;}
3536    _LIBCPP_INLINE_VISIBILITY void __incr(true_type) _NOEXCEPT
3537        {}
3538
3539    _LIBCPP_INLINE_VISIBILITY void __set(size_t __s, false_type) _NOEXCEPT
3540        {size = __s;}
3541    _LIBCPP_INLINE_VISIBILITY void __set(size_t, true_type) _NOEXCEPT
3542        {}
3543public:
3544    _LIBCPP_INLINE_VISIBILITY explicit __destruct_n(size_t __s) _NOEXCEPT
3545        : size(__s) {}
3546
3547    template <class _Tp>
3548    _LIBCPP_INLINE_VISIBILITY void __incr(_Tp*) _NOEXCEPT
3549        {__incr(integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3550
3551    template <class _Tp>
3552    _LIBCPP_INLINE_VISIBILITY void __set(size_t __s, _Tp*) _NOEXCEPT
3553        {__set(__s, integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3554
3555    template <class _Tp>
3556    _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) _NOEXCEPT
3557        {__process(__p, integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3558};
3559
3560template <class _Alloc>
3561class __allocator_destructor
3562{
3563    typedef allocator_traits<_Alloc> __alloc_traits;
3564public:
3565    typedef typename __alloc_traits::pointer pointer;
3566    typedef typename __alloc_traits::size_type size_type;
3567private:
3568    _Alloc& __alloc_;
3569    size_type __s_;
3570public:
3571    _LIBCPP_INLINE_VISIBILITY __allocator_destructor(_Alloc& __a, size_type __s)
3572             _NOEXCEPT
3573        : __alloc_(__a), __s_(__s) {}
3574    _LIBCPP_INLINE_VISIBILITY
3575    void operator()(pointer __p) _NOEXCEPT
3576        {__alloc_traits::deallocate(__alloc_, __p, __s_);}
3577};
3578
3579template <class _InputIterator, class _ForwardIterator>
3580_ForwardIterator
3581uninitialized_copy(_InputIterator __f, _InputIterator __l, _ForwardIterator __r)
3582{
3583    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3584#ifndef _LIBCPP_NO_EXCEPTIONS
3585    _ForwardIterator __s = __r;
3586    try
3587    {
3588#endif
3589        for (; __f != __l; ++__f, (void) ++__r)
3590            ::new (static_cast<void*>(_VSTD::addressof(*__r))) value_type(*__f);
3591#ifndef _LIBCPP_NO_EXCEPTIONS
3592    }
3593    catch (...)
3594    {
3595        for (; __s != __r; ++__s)
3596            __s->~value_type();
3597        throw;
3598    }
3599#endif
3600    return __r;
3601}
3602
3603template <class _InputIterator, class _Size, class _ForwardIterator>
3604_ForwardIterator
3605uninitialized_copy_n(_InputIterator __f, _Size __n, _ForwardIterator __r)
3606{
3607    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3608#ifndef _LIBCPP_NO_EXCEPTIONS
3609    _ForwardIterator __s = __r;
3610    try
3611    {
3612#endif
3613        for (; __n > 0; ++__f, (void) ++__r, (void) --__n)
3614            ::new (static_cast<void*>(_VSTD::addressof(*__r))) value_type(*__f);
3615#ifndef _LIBCPP_NO_EXCEPTIONS
3616    }
3617    catch (...)
3618    {
3619        for (; __s != __r; ++__s)
3620            __s->~value_type();
3621        throw;
3622    }
3623#endif
3624    return __r;
3625}
3626
3627template <class _ForwardIterator, class _Tp>
3628void
3629uninitialized_fill(_ForwardIterator __f, _ForwardIterator __l, const _Tp& __x)
3630{
3631    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3632#ifndef _LIBCPP_NO_EXCEPTIONS
3633    _ForwardIterator __s = __f;
3634    try
3635    {
3636#endif
3637        for (; __f != __l; ++__f)
3638            ::new (static_cast<void*>(_VSTD::addressof(*__f))) value_type(__x);
3639#ifndef _LIBCPP_NO_EXCEPTIONS
3640    }
3641    catch (...)
3642    {
3643        for (; __s != __f; ++__s)
3644            __s->~value_type();
3645        throw;
3646    }
3647#endif
3648}
3649
3650template <class _ForwardIterator, class _Size, class _Tp>
3651_ForwardIterator
3652uninitialized_fill_n(_ForwardIterator __f, _Size __n, const _Tp& __x)
3653{
3654    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3655#ifndef _LIBCPP_NO_EXCEPTIONS
3656    _ForwardIterator __s = __f;
3657    try
3658    {
3659#endif
3660        for (; __n > 0; ++__f, (void) --__n)
3661            ::new (static_cast<void*>(_VSTD::addressof(*__f))) value_type(__x);
3662#ifndef _LIBCPP_NO_EXCEPTIONS
3663    }
3664    catch (...)
3665    {
3666        for (; __s != __f; ++__s)
3667            __s->~value_type();
3668        throw;
3669    }
3670#endif
3671    return __f;
3672}
3673
3674class _LIBCPP_EXCEPTION_ABI bad_weak_ptr
3675    : public std::exception
3676{
3677public:
3678    virtual ~bad_weak_ptr() _NOEXCEPT;
3679    virtual const char* what() const  _NOEXCEPT;
3680};
3681
3682template<class _Tp> class _LIBCPP_TYPE_VIS_ONLY weak_ptr;
3683
3684class _LIBCPP_TYPE_VIS __shared_count
3685{
3686    __shared_count(const __shared_count&);
3687    __shared_count& operator=(const __shared_count&);
3688
3689protected:
3690    long __shared_owners_;
3691    virtual ~__shared_count();
3692private:
3693    virtual void __on_zero_shared() _NOEXCEPT = 0;
3694
3695public:
3696    _LIBCPP_INLINE_VISIBILITY
3697    explicit __shared_count(long __refs = 0) _NOEXCEPT
3698        : __shared_owners_(__refs) {}
3699
3700    void __add_shared() _NOEXCEPT;
3701    bool __release_shared() _NOEXCEPT;
3702    _LIBCPP_INLINE_VISIBILITY
3703    long use_count() const _NOEXCEPT {
3704        return __libcpp_relaxed_load(&__shared_owners_) + 1;
3705    }
3706};
3707
3708class _LIBCPP_TYPE_VIS __shared_weak_count
3709    : private __shared_count
3710{
3711    long __shared_weak_owners_;
3712
3713public:
3714    _LIBCPP_INLINE_VISIBILITY
3715    explicit __shared_weak_count(long __refs = 0) _NOEXCEPT
3716        : __shared_count(__refs),
3717          __shared_weak_owners_(__refs) {}
3718protected:
3719    virtual ~__shared_weak_count();
3720
3721public:
3722    void __add_shared() _NOEXCEPT;
3723    void __add_weak() _NOEXCEPT;
3724    void __release_shared() _NOEXCEPT;
3725    void __release_weak() _NOEXCEPT;
3726    _LIBCPP_INLINE_VISIBILITY
3727    long use_count() const _NOEXCEPT {return __shared_count::use_count();}
3728    __shared_weak_count* lock() _NOEXCEPT;
3729
3730    // Define the function out only if we build static libc++ without RTTI.
3731    // Otherwise we may break clients who need to compile their projects with
3732    // -fno-rtti and yet link against a libc++.dylib compiled
3733    // without -fno-rtti.
3734#if !defined(_LIBCPP_NO_RTTI) || !defined(_LIBCPP_BUILD_STATIC)
3735    virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
3736#endif
3737private:
3738    virtual void __on_zero_shared_weak() _NOEXCEPT = 0;
3739};
3740
3741template <class _Tp, class _Dp, class _Alloc>
3742class __shared_ptr_pointer
3743    : public __shared_weak_count
3744{
3745    __compressed_pair<__compressed_pair<_Tp, _Dp>, _Alloc> __data_;
3746public:
3747    _LIBCPP_INLINE_VISIBILITY
3748    __shared_ptr_pointer(_Tp __p, _Dp __d, _Alloc __a)
3749        :  __data_(__compressed_pair<_Tp, _Dp>(__p, _VSTD::move(__d)), _VSTD::move(__a)) {}
3750
3751#ifndef _LIBCPP_NO_RTTI
3752    virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
3753#endif
3754
3755private:
3756    virtual void __on_zero_shared() _NOEXCEPT;
3757    virtual void __on_zero_shared_weak() _NOEXCEPT;
3758};
3759
3760#ifndef _LIBCPP_NO_RTTI
3761
3762template <class _Tp, class _Dp, class _Alloc>
3763const void*
3764__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__get_deleter(const type_info& __t) const _NOEXCEPT
3765{
3766    return __t == typeid(_Dp) ? _VSTD::addressof(__data_.first().second()) : 0;
3767}
3768
3769#endif  // _LIBCPP_NO_RTTI
3770
3771template <class _Tp, class _Dp, class _Alloc>
3772void
3773__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared() _NOEXCEPT
3774{
3775    __data_.first().second()(__data_.first().first());
3776    __data_.first().second().~_Dp();
3777}
3778
3779template <class _Tp, class _Dp, class _Alloc>
3780void
3781__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
3782{
3783    typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_pointer>::type _Al;
3784    typedef allocator_traits<_Al> _ATraits;
3785    typedef pointer_traits<typename _ATraits::pointer> _PTraits;
3786
3787    _Al __a(__data_.second());
3788    __data_.second().~_Alloc();
3789    __a.deallocate(_PTraits::pointer_to(*this), 1);
3790}
3791
3792template <class _Tp, class _Alloc>
3793class __shared_ptr_emplace
3794    : public __shared_weak_count
3795{
3796    __compressed_pair<_Alloc, _Tp> __data_;
3797public:
3798#ifndef _LIBCPP_HAS_NO_VARIADICS
3799
3800    _LIBCPP_INLINE_VISIBILITY
3801    __shared_ptr_emplace(_Alloc __a)
3802        :  __data_(_VSTD::move(__a)) {}
3803
3804    template <class ..._Args>
3805        _LIBCPP_INLINE_VISIBILITY
3806        __shared_ptr_emplace(_Alloc __a, _Args&& ...__args)
3807            :  __data_(piecewise_construct, _VSTD::forward_as_tuple(__a),
3808                   _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...)) {}
3809
3810#else  // _LIBCPP_HAS_NO_VARIADICS
3811
3812    _LIBCPP_INLINE_VISIBILITY
3813    __shared_ptr_emplace(_Alloc __a)
3814        :  __data_(__a) {}
3815
3816    template <class _A0>
3817        _LIBCPP_INLINE_VISIBILITY
3818        __shared_ptr_emplace(_Alloc __a, _A0& __a0)
3819            :  __data_(__a, _Tp(__a0)) {}
3820
3821    template <class _A0, class _A1>
3822        _LIBCPP_INLINE_VISIBILITY
3823        __shared_ptr_emplace(_Alloc __a, _A0& __a0, _A1& __a1)
3824            :  __data_(__a, _Tp(__a0, __a1)) {}
3825
3826    template <class _A0, class _A1, class _A2>
3827        _LIBCPP_INLINE_VISIBILITY
3828        __shared_ptr_emplace(_Alloc __a, _A0& __a0, _A1& __a1, _A2& __a2)
3829            :  __data_(__a, _Tp(__a0, __a1, __a2)) {}
3830
3831#endif  // _LIBCPP_HAS_NO_VARIADICS
3832
3833private:
3834    virtual void __on_zero_shared() _NOEXCEPT;
3835    virtual void __on_zero_shared_weak() _NOEXCEPT;
3836public:
3837    _LIBCPP_INLINE_VISIBILITY
3838    _Tp* get() _NOEXCEPT {return &__data_.second();}
3839};
3840
3841template <class _Tp, class _Alloc>
3842void
3843__shared_ptr_emplace<_Tp, _Alloc>::__on_zero_shared() _NOEXCEPT
3844{
3845    __data_.second().~_Tp();
3846}
3847
3848template <class _Tp, class _Alloc>
3849void
3850__shared_ptr_emplace<_Tp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
3851{
3852    typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_emplace>::type _Al;
3853    typedef allocator_traits<_Al> _ATraits;
3854    typedef pointer_traits<typename _ATraits::pointer> _PTraits;
3855    _Al __a(__data_.first());
3856    __data_.first().~_Alloc();
3857    __a.deallocate(_PTraits::pointer_to(*this), 1);
3858}
3859
3860template<class _Tp> class _LIBCPP_TYPE_VIS_ONLY enable_shared_from_this;
3861
3862template<class _Tp>
3863class _LIBCPP_TYPE_VIS_ONLY shared_ptr
3864{
3865public:
3866    typedef _Tp element_type;
3867private:
3868    element_type*      __ptr_;
3869    __shared_weak_count* __cntrl_;
3870
3871    struct __nat {int __for_bool_;};
3872public:
3873    _LIBCPP_CONSTEXPR shared_ptr() _NOEXCEPT;
3874    _LIBCPP_CONSTEXPR shared_ptr(nullptr_t) _NOEXCEPT;
3875    template<class _Yp>
3876        explicit shared_ptr(_Yp* __p,
3877                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3878    template<class _Yp, class _Dp>
3879        shared_ptr(_Yp* __p, _Dp __d,
3880                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3881    template<class _Yp, class _Dp, class _Alloc>
3882        shared_ptr(_Yp* __p, _Dp __d, _Alloc __a,
3883                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3884    template <class _Dp> shared_ptr(nullptr_t __p, _Dp __d);
3885    template <class _Dp, class _Alloc> shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a);
3886    template<class _Yp> shared_ptr(const shared_ptr<_Yp>& __r, element_type* __p) _NOEXCEPT;
3887    shared_ptr(const shared_ptr& __r) _NOEXCEPT;
3888    template<class _Yp>
3889        shared_ptr(const shared_ptr<_Yp>& __r,
3890                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type = __nat())
3891                       _NOEXCEPT;
3892#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3893    shared_ptr(shared_ptr&& __r) _NOEXCEPT;
3894    template<class _Yp> shared_ptr(shared_ptr<_Yp>&& __r,
3895                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type = __nat())
3896                       _NOEXCEPT;
3897#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3898    template<class _Yp> explicit shared_ptr(const weak_ptr<_Yp>& __r,
3899                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type= __nat());
3900#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3901    template<class _Yp>
3902        shared_ptr(auto_ptr<_Yp>&& __r,
3903                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3904#else
3905    template<class _Yp>
3906        shared_ptr(auto_ptr<_Yp> __r,
3907                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3908#endif
3909#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3910    template <class _Yp, class _Dp>
3911        shared_ptr(unique_ptr<_Yp, _Dp>&&,
3912                   typename enable_if
3913                   <
3914                       !is_lvalue_reference<_Dp>::value &&
3915                       !is_array<_Yp>::value &&
3916                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3917                       __nat
3918                   >::type = __nat());
3919    template <class _Yp, class _Dp>
3920        shared_ptr(unique_ptr<_Yp, _Dp>&&,
3921                   typename enable_if
3922                   <
3923                       is_lvalue_reference<_Dp>::value &&
3924                       !is_array<_Yp>::value &&
3925                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3926                       __nat
3927                   >::type = __nat());
3928#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3929    template <class _Yp, class _Dp>
3930        shared_ptr(unique_ptr<_Yp, _Dp>,
3931                   typename enable_if
3932                   <
3933                       !is_lvalue_reference<_Dp>::value &&
3934                       !is_array<_Yp>::value &&
3935                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3936                       __nat
3937                   >::type = __nat());
3938    template <class _Yp, class _Dp>
3939        shared_ptr(unique_ptr<_Yp, _Dp>,
3940                   typename enable_if
3941                   <
3942                       is_lvalue_reference<_Dp>::value &&
3943                       !is_array<_Yp>::value &&
3944                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3945                       __nat
3946                   >::type = __nat());
3947#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3948
3949    ~shared_ptr();
3950
3951    shared_ptr& operator=(const shared_ptr& __r) _NOEXCEPT;
3952    template<class _Yp>
3953        typename enable_if
3954        <
3955            is_convertible<_Yp*, element_type*>::value,
3956            shared_ptr&
3957        >::type
3958        operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT;
3959#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3960    shared_ptr& operator=(shared_ptr&& __r) _NOEXCEPT;
3961    template<class _Yp>
3962        typename enable_if
3963        <
3964            is_convertible<_Yp*, element_type*>::value,
3965            shared_ptr<_Tp>&
3966        >::type
3967        operator=(shared_ptr<_Yp>&& __r);
3968    template<class _Yp>
3969        typename enable_if
3970        <
3971            !is_array<_Yp>::value &&
3972            is_convertible<_Yp*, element_type*>::value,
3973            shared_ptr
3974        >::type&
3975        operator=(auto_ptr<_Yp>&& __r);
3976#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3977    template<class _Yp>
3978        typename enable_if
3979        <
3980            !is_array<_Yp>::value &&
3981            is_convertible<_Yp*, element_type*>::value,
3982            shared_ptr&
3983        >::type
3984        operator=(auto_ptr<_Yp> __r);
3985#endif
3986    template <class _Yp, class _Dp>
3987        typename enable_if
3988        <
3989            !is_array<_Yp>::value &&
3990            is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3991            shared_ptr&
3992        >::type
3993#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3994        operator=(unique_ptr<_Yp, _Dp>&& __r);
3995#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3996        operator=(unique_ptr<_Yp, _Dp> __r);
3997#endif
3998
3999    void swap(shared_ptr& __r) _NOEXCEPT;
4000    void reset() _NOEXCEPT;
4001    template<class _Yp>
4002        typename enable_if
4003        <
4004            is_convertible<_Yp*, element_type*>::value,
4005            void
4006        >::type
4007        reset(_Yp* __p);
4008    template<class _Yp, class _Dp>
4009        typename enable_if
4010        <
4011            is_convertible<_Yp*, element_type*>::value,
4012            void
4013        >::type
4014        reset(_Yp* __p, _Dp __d);
4015    template<class _Yp, class _Dp, class _Alloc>
4016        typename enable_if
4017        <
4018            is_convertible<_Yp*, element_type*>::value,
4019            void
4020        >::type
4021        reset(_Yp* __p, _Dp __d, _Alloc __a);
4022
4023    _LIBCPP_INLINE_VISIBILITY
4024    element_type* get() const _NOEXCEPT {return __ptr_;}
4025    _LIBCPP_INLINE_VISIBILITY
4026    typename add_lvalue_reference<element_type>::type operator*() const _NOEXCEPT
4027        {return *__ptr_;}
4028    _LIBCPP_INLINE_VISIBILITY
4029    element_type* operator->() const _NOEXCEPT {return __ptr_;}
4030    _LIBCPP_INLINE_VISIBILITY
4031    long use_count() const _NOEXCEPT {return __cntrl_ ? __cntrl_->use_count() : 0;}
4032    _LIBCPP_INLINE_VISIBILITY
4033    bool unique() const _NOEXCEPT {return use_count() == 1;}
4034    _LIBCPP_INLINE_VISIBILITY
4035    _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {return get() != 0;}
4036    template <class _Up>
4037        _LIBCPP_INLINE_VISIBILITY
4038        bool owner_before(shared_ptr<_Up> const& __p) const
4039        {return __cntrl_ < __p.__cntrl_;}
4040    template <class _Up>
4041        _LIBCPP_INLINE_VISIBILITY
4042        bool owner_before(weak_ptr<_Up> const& __p) const
4043        {return __cntrl_ < __p.__cntrl_;}
4044    _LIBCPP_INLINE_VISIBILITY
4045    bool
4046    __owner_equivalent(const shared_ptr& __p) const
4047        {return __cntrl_ == __p.__cntrl_;}
4048
4049#ifndef _LIBCPP_NO_RTTI
4050    template <class _Dp>
4051        _LIBCPP_INLINE_VISIBILITY
4052        _Dp* __get_deleter() const _NOEXCEPT
4053            {return (_Dp*)(__cntrl_ ? __cntrl_->__get_deleter(typeid(_Dp)) : 0);}
4054#endif  // _LIBCPP_NO_RTTI
4055
4056#ifndef _LIBCPP_HAS_NO_VARIADICS
4057
4058    template<class ..._Args>
4059        static
4060        shared_ptr<_Tp>
4061        make_shared(_Args&& ...__args);
4062
4063    template<class _Alloc, class ..._Args>
4064        static
4065        shared_ptr<_Tp>
4066        allocate_shared(const _Alloc& __a, _Args&& ...__args);
4067
4068#else  // _LIBCPP_HAS_NO_VARIADICS
4069
4070    static shared_ptr<_Tp> make_shared();
4071
4072    template<class _A0>
4073        static shared_ptr<_Tp> make_shared(_A0&);
4074
4075    template<class _A0, class _A1>
4076        static shared_ptr<_Tp> make_shared(_A0&, _A1&);
4077
4078    template<class _A0, class _A1, class _A2>
4079        static shared_ptr<_Tp> make_shared(_A0&, _A1&, _A2&);
4080
4081    template<class _Alloc>
4082        static shared_ptr<_Tp>
4083        allocate_shared(const _Alloc& __a);
4084
4085    template<class _Alloc, class _A0>
4086        static shared_ptr<_Tp>
4087        allocate_shared(const _Alloc& __a, _A0& __a0);
4088
4089    template<class _Alloc, class _A0, class _A1>
4090        static shared_ptr<_Tp>
4091        allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1);
4092
4093    template<class _Alloc, class _A0, class _A1, class _A2>
4094        static shared_ptr<_Tp>
4095        allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2);
4096
4097#endif  // _LIBCPP_HAS_NO_VARIADICS
4098
4099private:
4100
4101    template <class _Yp>
4102        _LIBCPP_INLINE_VISIBILITY
4103        void
4104        __enable_weak_this(const enable_shared_from_this<_Yp>* __e) _NOEXCEPT
4105        {
4106            if (__e)
4107            {
4108                __e->__weak_this_.__ptr_ = const_cast<_Yp*>(static_cast<const _Yp*>(__e));
4109                __e->__weak_this_.__cntrl_ = __cntrl_;
4110                __cntrl_->__add_weak();
4111            }
4112        }
4113
4114    _LIBCPP_INLINE_VISIBILITY
4115    void __enable_weak_this(const volatile void*) _NOEXCEPT {}
4116
4117    template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY shared_ptr;
4118    template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY weak_ptr;
4119};
4120
4121template<class _Tp>
4122inline _LIBCPP_INLINE_VISIBILITY
4123_LIBCPP_CONSTEXPR
4124shared_ptr<_Tp>::shared_ptr() _NOEXCEPT
4125    : __ptr_(0),
4126      __cntrl_(0)
4127{
4128}
4129
4130template<class _Tp>
4131inline _LIBCPP_INLINE_VISIBILITY
4132_LIBCPP_CONSTEXPR
4133shared_ptr<_Tp>::shared_ptr(nullptr_t) _NOEXCEPT
4134    : __ptr_(0),
4135      __cntrl_(0)
4136{
4137}
4138
4139template<class _Tp>
4140template<class _Yp>
4141shared_ptr<_Tp>::shared_ptr(_Yp* __p,
4142                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4143    : __ptr_(__p)
4144{
4145    unique_ptr<_Yp> __hold(__p);
4146    typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk;
4147    __cntrl_ = new _CntrlBlk(__p, default_delete<_Yp>(), allocator<_Yp>());
4148    __hold.release();
4149    __enable_weak_this(__p);
4150}
4151
4152template<class _Tp>
4153template<class _Yp, class _Dp>
4154shared_ptr<_Tp>::shared_ptr(_Yp* __p, _Dp __d,
4155                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4156    : __ptr_(__p)
4157{
4158#ifndef _LIBCPP_NO_EXCEPTIONS
4159    try
4160    {
4161#endif  // _LIBCPP_NO_EXCEPTIONS
4162        typedef __shared_ptr_pointer<_Yp*, _Dp, allocator<_Yp> > _CntrlBlk;
4163        __cntrl_ = new _CntrlBlk(__p, __d, allocator<_Yp>());
4164        __enable_weak_this(__p);
4165#ifndef _LIBCPP_NO_EXCEPTIONS
4166    }
4167    catch (...)
4168    {
4169        __d(__p);
4170        throw;
4171    }
4172#endif  // _LIBCPP_NO_EXCEPTIONS
4173}
4174
4175template<class _Tp>
4176template<class _Dp>
4177shared_ptr<_Tp>::shared_ptr(nullptr_t __p, _Dp __d)
4178    : __ptr_(0)
4179{
4180#ifndef _LIBCPP_NO_EXCEPTIONS
4181    try
4182    {
4183#endif  // _LIBCPP_NO_EXCEPTIONS
4184        typedef __shared_ptr_pointer<nullptr_t, _Dp, allocator<_Tp> > _CntrlBlk;
4185        __cntrl_ = new _CntrlBlk(__p, __d, allocator<_Tp>());
4186#ifndef _LIBCPP_NO_EXCEPTIONS
4187    }
4188    catch (...)
4189    {
4190        __d(__p);
4191        throw;
4192    }
4193#endif  // _LIBCPP_NO_EXCEPTIONS
4194}
4195
4196template<class _Tp>
4197template<class _Yp, class _Dp, class _Alloc>
4198shared_ptr<_Tp>::shared_ptr(_Yp* __p, _Dp __d, _Alloc __a,
4199                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4200    : __ptr_(__p)
4201{
4202#ifndef _LIBCPP_NO_EXCEPTIONS
4203    try
4204    {
4205#endif  // _LIBCPP_NO_EXCEPTIONS
4206        typedef __shared_ptr_pointer<_Yp*, _Dp, _Alloc> _CntrlBlk;
4207        typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4208        typedef __allocator_destructor<_A2> _D2;
4209        _A2 __a2(__a);
4210        unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4211        ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4212            _CntrlBlk(__p, __d, __a);
4213        __cntrl_ = _VSTD::addressof(*__hold2.release());
4214        __enable_weak_this(__p);
4215#ifndef _LIBCPP_NO_EXCEPTIONS
4216    }
4217    catch (...)
4218    {
4219        __d(__p);
4220        throw;
4221    }
4222#endif  // _LIBCPP_NO_EXCEPTIONS
4223}
4224
4225template<class _Tp>
4226template<class _Dp, class _Alloc>
4227shared_ptr<_Tp>::shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a)
4228    : __ptr_(0)
4229{
4230#ifndef _LIBCPP_NO_EXCEPTIONS
4231    try
4232    {
4233#endif  // _LIBCPP_NO_EXCEPTIONS
4234        typedef __shared_ptr_pointer<nullptr_t, _Dp, _Alloc> _CntrlBlk;
4235        typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4236        typedef __allocator_destructor<_A2> _D2;
4237        _A2 __a2(__a);
4238        unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4239        ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4240            _CntrlBlk(__p, __d, __a);
4241        __cntrl_ = _VSTD::addressof(*__hold2.release());
4242#ifndef _LIBCPP_NO_EXCEPTIONS
4243    }
4244    catch (...)
4245    {
4246        __d(__p);
4247        throw;
4248    }
4249#endif  // _LIBCPP_NO_EXCEPTIONS
4250}
4251
4252template<class _Tp>
4253template<class _Yp>
4254inline _LIBCPP_INLINE_VISIBILITY
4255shared_ptr<_Tp>::shared_ptr(const shared_ptr<_Yp>& __r, element_type *__p) _NOEXCEPT
4256    : __ptr_(__p),
4257      __cntrl_(__r.__cntrl_)
4258{
4259    if (__cntrl_)
4260        __cntrl_->__add_shared();
4261}
4262
4263template<class _Tp>
4264inline _LIBCPP_INLINE_VISIBILITY
4265shared_ptr<_Tp>::shared_ptr(const shared_ptr& __r) _NOEXCEPT
4266    : __ptr_(__r.__ptr_),
4267      __cntrl_(__r.__cntrl_)
4268{
4269    if (__cntrl_)
4270        __cntrl_->__add_shared();
4271}
4272
4273template<class _Tp>
4274template<class _Yp>
4275inline _LIBCPP_INLINE_VISIBILITY
4276shared_ptr<_Tp>::shared_ptr(const shared_ptr<_Yp>& __r,
4277                            typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type)
4278         _NOEXCEPT
4279    : __ptr_(__r.__ptr_),
4280      __cntrl_(__r.__cntrl_)
4281{
4282    if (__cntrl_)
4283        __cntrl_->__add_shared();
4284}
4285
4286#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4287
4288template<class _Tp>
4289inline _LIBCPP_INLINE_VISIBILITY
4290shared_ptr<_Tp>::shared_ptr(shared_ptr&& __r) _NOEXCEPT
4291    : __ptr_(__r.__ptr_),
4292      __cntrl_(__r.__cntrl_)
4293{
4294    __r.__ptr_ = 0;
4295    __r.__cntrl_ = 0;
4296}
4297
4298template<class _Tp>
4299template<class _Yp>
4300inline _LIBCPP_INLINE_VISIBILITY
4301shared_ptr<_Tp>::shared_ptr(shared_ptr<_Yp>&& __r,
4302                            typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type)
4303         _NOEXCEPT
4304    : __ptr_(__r.__ptr_),
4305      __cntrl_(__r.__cntrl_)
4306{
4307    __r.__ptr_ = 0;
4308    __r.__cntrl_ = 0;
4309}
4310
4311#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4312
4313template<class _Tp>
4314template<class _Yp>
4315#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4316shared_ptr<_Tp>::shared_ptr(auto_ptr<_Yp>&& __r,
4317#else
4318shared_ptr<_Tp>::shared_ptr(auto_ptr<_Yp> __r,
4319#endif
4320                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4321    : __ptr_(__r.get())
4322{
4323    typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk;
4324    __cntrl_ = new _CntrlBlk(__r.get(), default_delete<_Yp>(), allocator<_Yp>());
4325    __enable_weak_this(__r.get());
4326    __r.release();
4327}
4328
4329template<class _Tp>
4330template <class _Yp, class _Dp>
4331#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4332shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
4333#else
4334shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
4335#endif
4336                            typename enable_if
4337                            <
4338                                !is_lvalue_reference<_Dp>::value &&
4339                                !is_array<_Yp>::value &&
4340                                is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4341                                __nat
4342                            >::type)
4343    : __ptr_(__r.get())
4344{
4345#if _LIBCPP_STD_VER > 11
4346    if (__ptr_ == nullptr)
4347        __cntrl_ = nullptr;
4348    else
4349#endif
4350    {
4351        typedef __shared_ptr_pointer<_Yp*, _Dp, allocator<_Yp> > _CntrlBlk;
4352        __cntrl_ = new _CntrlBlk(__r.get(), __r.get_deleter(), allocator<_Yp>());
4353        __enable_weak_this(__r.get());
4354    }
4355    __r.release();
4356}
4357
4358template<class _Tp>
4359template <class _Yp, class _Dp>
4360#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4361shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
4362#else
4363shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
4364#endif
4365                            typename enable_if
4366                            <
4367                                is_lvalue_reference<_Dp>::value &&
4368                                !is_array<_Yp>::value &&
4369                                is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4370                                __nat
4371                            >::type)
4372    : __ptr_(__r.get())
4373{
4374#if _LIBCPP_STD_VER > 11
4375    if (__ptr_ == nullptr)
4376        __cntrl_ = nullptr;
4377    else
4378#endif
4379    {
4380        typedef __shared_ptr_pointer<_Yp*,
4381                                     reference_wrapper<typename remove_reference<_Dp>::type>,
4382                                     allocator<_Yp> > _CntrlBlk;
4383        __cntrl_ = new _CntrlBlk(__r.get(), ref(__r.get_deleter()), allocator<_Yp>());
4384        __enable_weak_this(__r.get());
4385    }
4386    __r.release();
4387}
4388
4389#ifndef _LIBCPP_HAS_NO_VARIADICS
4390
4391template<class _Tp>
4392template<class ..._Args>
4393shared_ptr<_Tp>
4394shared_ptr<_Tp>::make_shared(_Args&& ...__args)
4395{
4396    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4397    typedef allocator<_CntrlBlk> _A2;
4398    typedef __allocator_destructor<_A2> _D2;
4399    _A2 __a2;
4400    unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4401    ::new(__hold2.get()) _CntrlBlk(__a2, _VSTD::forward<_Args>(__args)...);
4402    shared_ptr<_Tp> __r;
4403    __r.__ptr_ = __hold2.get()->get();
4404    __r.__cntrl_ = __hold2.release();
4405    __r.__enable_weak_this(__r.__ptr_);
4406    return __r;
4407}
4408
4409template<class _Tp>
4410template<class _Alloc, class ..._Args>
4411shared_ptr<_Tp>
4412shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _Args&& ...__args)
4413{
4414    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4415    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4416    typedef __allocator_destructor<_A2> _D2;
4417    _A2 __a2(__a);
4418    unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4419    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4420        _CntrlBlk(__a, _VSTD::forward<_Args>(__args)...);
4421    shared_ptr<_Tp> __r;
4422    __r.__ptr_ = __hold2.get()->get();
4423    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4424    __r.__enable_weak_this(__r.__ptr_);
4425    return __r;
4426}
4427
4428#else  // _LIBCPP_HAS_NO_VARIADICS
4429
4430template<class _Tp>
4431shared_ptr<_Tp>
4432shared_ptr<_Tp>::make_shared()
4433{
4434    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4435    typedef allocator<_CntrlBlk> _Alloc2;
4436    typedef __allocator_destructor<_Alloc2> _D2;
4437    _Alloc2 __alloc2;
4438    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4439    ::new(__hold2.get()) _CntrlBlk(__alloc2);
4440    shared_ptr<_Tp> __r;
4441    __r.__ptr_ = __hold2.get()->get();
4442    __r.__cntrl_ = __hold2.release();
4443    __r.__enable_weak_this(__r.__ptr_);
4444    return __r;
4445}
4446
4447template<class _Tp>
4448template<class _A0>
4449shared_ptr<_Tp>
4450shared_ptr<_Tp>::make_shared(_A0& __a0)
4451{
4452    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4453    typedef allocator<_CntrlBlk> _Alloc2;
4454    typedef __allocator_destructor<_Alloc2> _D2;
4455    _Alloc2 __alloc2;
4456    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4457    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0);
4458    shared_ptr<_Tp> __r;
4459    __r.__ptr_ = __hold2.get()->get();
4460    __r.__cntrl_ = __hold2.release();
4461    __r.__enable_weak_this(__r.__ptr_);
4462    return __r;
4463}
4464
4465template<class _Tp>
4466template<class _A0, class _A1>
4467shared_ptr<_Tp>
4468shared_ptr<_Tp>::make_shared(_A0& __a0, _A1& __a1)
4469{
4470    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4471    typedef allocator<_CntrlBlk> _Alloc2;
4472    typedef __allocator_destructor<_Alloc2> _D2;
4473    _Alloc2 __alloc2;
4474    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4475    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0, __a1);
4476    shared_ptr<_Tp> __r;
4477    __r.__ptr_ = __hold2.get()->get();
4478    __r.__cntrl_ = __hold2.release();
4479    __r.__enable_weak_this(__r.__ptr_);
4480    return __r;
4481}
4482
4483template<class _Tp>
4484template<class _A0, class _A1, class _A2>
4485shared_ptr<_Tp>
4486shared_ptr<_Tp>::make_shared(_A0& __a0, _A1& __a1, _A2& __a2)
4487{
4488    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4489    typedef allocator<_CntrlBlk> _Alloc2;
4490    typedef __allocator_destructor<_Alloc2> _D2;
4491    _Alloc2 __alloc2;
4492    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4493    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0, __a1, __a2);
4494    shared_ptr<_Tp> __r;
4495    __r.__ptr_ = __hold2.get()->get();
4496    __r.__cntrl_ = __hold2.release();
4497    __r.__enable_weak_this(__r.__ptr_);
4498    return __r;
4499}
4500
4501template<class _Tp>
4502template<class _Alloc>
4503shared_ptr<_Tp>
4504shared_ptr<_Tp>::allocate_shared(const _Alloc& __a)
4505{
4506    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4507    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4508    typedef __allocator_destructor<_Alloc2> _D2;
4509    _Alloc2 __alloc2(__a);
4510    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4511    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4512        _CntrlBlk(__a);
4513    shared_ptr<_Tp> __r;
4514    __r.__ptr_ = __hold2.get()->get();
4515    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4516    __r.__enable_weak_this(__r.__ptr_);
4517    return __r;
4518}
4519
4520template<class _Tp>
4521template<class _Alloc, class _A0>
4522shared_ptr<_Tp>
4523shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0)
4524{
4525    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4526    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4527    typedef __allocator_destructor<_Alloc2> _D2;
4528    _Alloc2 __alloc2(__a);
4529    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4530    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4531        _CntrlBlk(__a, __a0);
4532    shared_ptr<_Tp> __r;
4533    __r.__ptr_ = __hold2.get()->get();
4534    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4535    __r.__enable_weak_this(__r.__ptr_);
4536    return __r;
4537}
4538
4539template<class _Tp>
4540template<class _Alloc, class _A0, class _A1>
4541shared_ptr<_Tp>
4542shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1)
4543{
4544    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4545    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4546    typedef __allocator_destructor<_Alloc2> _D2;
4547    _Alloc2 __alloc2(__a);
4548    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4549    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4550        _CntrlBlk(__a, __a0, __a1);
4551    shared_ptr<_Tp> __r;
4552    __r.__ptr_ = __hold2.get()->get();
4553    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4554    __r.__enable_weak_this(__r.__ptr_);
4555    return __r;
4556}
4557
4558template<class _Tp>
4559template<class _Alloc, class _A0, class _A1, class _A2>
4560shared_ptr<_Tp>
4561shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2)
4562{
4563    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4564    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4565    typedef __allocator_destructor<_Alloc2> _D2;
4566    _Alloc2 __alloc2(__a);
4567    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4568    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4569        _CntrlBlk(__a, __a0, __a1, __a2);
4570    shared_ptr<_Tp> __r;
4571    __r.__ptr_ = __hold2.get()->get();
4572    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4573    __r.__enable_weak_this(__r.__ptr_);
4574    return __r;
4575}
4576
4577#endif  // _LIBCPP_HAS_NO_VARIADICS
4578
4579template<class _Tp>
4580shared_ptr<_Tp>::~shared_ptr()
4581{
4582    if (__cntrl_)
4583        __cntrl_->__release_shared();
4584}
4585
4586template<class _Tp>
4587inline _LIBCPP_INLINE_VISIBILITY
4588shared_ptr<_Tp>&
4589shared_ptr<_Tp>::operator=(const shared_ptr& __r) _NOEXCEPT
4590{
4591    shared_ptr(__r).swap(*this);
4592    return *this;
4593}
4594
4595template<class _Tp>
4596template<class _Yp>
4597inline _LIBCPP_INLINE_VISIBILITY
4598typename enable_if
4599<
4600    is_convertible<_Yp*, _Tp*>::value,
4601    shared_ptr<_Tp>&
4602>::type
4603shared_ptr<_Tp>::operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT
4604{
4605    shared_ptr(__r).swap(*this);
4606    return *this;
4607}
4608
4609#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4610
4611template<class _Tp>
4612inline _LIBCPP_INLINE_VISIBILITY
4613shared_ptr<_Tp>&
4614shared_ptr<_Tp>::operator=(shared_ptr&& __r) _NOEXCEPT
4615{
4616    shared_ptr(_VSTD::move(__r)).swap(*this);
4617    return *this;
4618}
4619
4620template<class _Tp>
4621template<class _Yp>
4622inline _LIBCPP_INLINE_VISIBILITY
4623typename enable_if
4624<
4625    is_convertible<_Yp*, _Tp*>::value,
4626    shared_ptr<_Tp>&
4627>::type
4628shared_ptr<_Tp>::operator=(shared_ptr<_Yp>&& __r)
4629{
4630    shared_ptr(_VSTD::move(__r)).swap(*this);
4631    return *this;
4632}
4633
4634template<class _Tp>
4635template<class _Yp>
4636inline _LIBCPP_INLINE_VISIBILITY
4637typename enable_if
4638<
4639    !is_array<_Yp>::value &&
4640    is_convertible<_Yp*, _Tp*>::value,
4641    shared_ptr<_Tp>
4642>::type&
4643shared_ptr<_Tp>::operator=(auto_ptr<_Yp>&& __r)
4644{
4645    shared_ptr(_VSTD::move(__r)).swap(*this);
4646    return *this;
4647}
4648
4649template<class _Tp>
4650template <class _Yp, class _Dp>
4651inline _LIBCPP_INLINE_VISIBILITY
4652typename enable_if
4653<
4654    !is_array<_Yp>::value &&
4655    is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, _Tp*>::value,
4656    shared_ptr<_Tp>&
4657>::type
4658shared_ptr<_Tp>::operator=(unique_ptr<_Yp, _Dp>&& __r)
4659{
4660    shared_ptr(_VSTD::move(__r)).swap(*this);
4661    return *this;
4662}
4663
4664#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4665
4666template<class _Tp>
4667template<class _Yp>
4668inline _LIBCPP_INLINE_VISIBILITY
4669typename enable_if
4670<
4671    !is_array<_Yp>::value &&
4672    is_convertible<_Yp*, _Tp*>::value,
4673    shared_ptr<_Tp>&
4674>::type
4675shared_ptr<_Tp>::operator=(auto_ptr<_Yp> __r)
4676{
4677    shared_ptr(__r).swap(*this);
4678    return *this;
4679}
4680
4681template<class _Tp>
4682template <class _Yp, class _Dp>
4683inline _LIBCPP_INLINE_VISIBILITY
4684typename enable_if
4685<
4686    !is_array<_Yp>::value &&
4687    is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, _Tp*>::value,
4688    shared_ptr<_Tp>&
4689>::type
4690shared_ptr<_Tp>::operator=(unique_ptr<_Yp, _Dp> __r)
4691{
4692    shared_ptr(_VSTD::move(__r)).swap(*this);
4693    return *this;
4694}
4695
4696#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4697
4698template<class _Tp>
4699inline _LIBCPP_INLINE_VISIBILITY
4700void
4701shared_ptr<_Tp>::swap(shared_ptr& __r) _NOEXCEPT
4702{
4703    _VSTD::swap(__ptr_, __r.__ptr_);
4704    _VSTD::swap(__cntrl_, __r.__cntrl_);
4705}
4706
4707template<class _Tp>
4708inline _LIBCPP_INLINE_VISIBILITY
4709void
4710shared_ptr<_Tp>::reset() _NOEXCEPT
4711{
4712    shared_ptr().swap(*this);
4713}
4714
4715template<class _Tp>
4716template<class _Yp>
4717inline _LIBCPP_INLINE_VISIBILITY
4718typename enable_if
4719<
4720    is_convertible<_Yp*, _Tp*>::value,
4721    void
4722>::type
4723shared_ptr<_Tp>::reset(_Yp* __p)
4724{
4725    shared_ptr(__p).swap(*this);
4726}
4727
4728template<class _Tp>
4729template<class _Yp, class _Dp>
4730inline _LIBCPP_INLINE_VISIBILITY
4731typename enable_if
4732<
4733    is_convertible<_Yp*, _Tp*>::value,
4734    void
4735>::type
4736shared_ptr<_Tp>::reset(_Yp* __p, _Dp __d)
4737{
4738    shared_ptr(__p, __d).swap(*this);
4739}
4740
4741template<class _Tp>
4742template<class _Yp, class _Dp, class _Alloc>
4743inline _LIBCPP_INLINE_VISIBILITY
4744typename enable_if
4745<
4746    is_convertible<_Yp*, _Tp*>::value,
4747    void
4748>::type
4749shared_ptr<_Tp>::reset(_Yp* __p, _Dp __d, _Alloc __a)
4750{
4751    shared_ptr(__p, __d, __a).swap(*this);
4752}
4753
4754#ifndef _LIBCPP_HAS_NO_VARIADICS
4755
4756template<class _Tp, class ..._Args>
4757inline _LIBCPP_INLINE_VISIBILITY
4758typename enable_if
4759<
4760    !is_array<_Tp>::value,
4761    shared_ptr<_Tp>
4762>::type
4763make_shared(_Args&& ...__args)
4764{
4765    return shared_ptr<_Tp>::make_shared(_VSTD::forward<_Args>(__args)...);
4766}
4767
4768template<class _Tp, class _Alloc, class ..._Args>
4769inline _LIBCPP_INLINE_VISIBILITY
4770typename enable_if
4771<
4772    !is_array<_Tp>::value,
4773    shared_ptr<_Tp>
4774>::type
4775allocate_shared(const _Alloc& __a, _Args&& ...__args)
4776{
4777    return shared_ptr<_Tp>::allocate_shared(__a, _VSTD::forward<_Args>(__args)...);
4778}
4779
4780#else  // _LIBCPP_HAS_NO_VARIADICS
4781
4782template<class _Tp>
4783inline _LIBCPP_INLINE_VISIBILITY
4784shared_ptr<_Tp>
4785make_shared()
4786{
4787    return shared_ptr<_Tp>::make_shared();
4788}
4789
4790template<class _Tp, class _A0>
4791inline _LIBCPP_INLINE_VISIBILITY
4792shared_ptr<_Tp>
4793make_shared(_A0& __a0)
4794{
4795    return shared_ptr<_Tp>::make_shared(__a0);
4796}
4797
4798template<class _Tp, class _A0, class _A1>
4799inline _LIBCPP_INLINE_VISIBILITY
4800shared_ptr<_Tp>
4801make_shared(_A0& __a0, _A1& __a1)
4802{
4803    return shared_ptr<_Tp>::make_shared(__a0, __a1);
4804}
4805
4806template<class _Tp, class _A0, class _A1, class _A2>
4807inline _LIBCPP_INLINE_VISIBILITY
4808shared_ptr<_Tp>
4809make_shared(_A0& __a0, _A1& __a1, _A2& __a2)
4810{
4811    return shared_ptr<_Tp>::make_shared(__a0, __a1, __a2);
4812}
4813
4814template<class _Tp, class _Alloc>
4815inline _LIBCPP_INLINE_VISIBILITY
4816shared_ptr<_Tp>
4817allocate_shared(const _Alloc& __a)
4818{
4819    return shared_ptr<_Tp>::allocate_shared(__a);
4820}
4821
4822template<class _Tp, class _Alloc, class _A0>
4823inline _LIBCPP_INLINE_VISIBILITY
4824shared_ptr<_Tp>
4825allocate_shared(const _Alloc& __a, _A0& __a0)
4826{
4827    return shared_ptr<_Tp>::allocate_shared(__a, __a0);
4828}
4829
4830template<class _Tp, class _Alloc, class _A0, class _A1>
4831inline _LIBCPP_INLINE_VISIBILITY
4832shared_ptr<_Tp>
4833allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1)
4834{
4835    return shared_ptr<_Tp>::allocate_shared(__a, __a0, __a1);
4836}
4837
4838template<class _Tp, class _Alloc, class _A0, class _A1, class _A2>
4839inline _LIBCPP_INLINE_VISIBILITY
4840shared_ptr<_Tp>
4841allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2)
4842{
4843    return shared_ptr<_Tp>::allocate_shared(__a, __a0, __a1, __a2);
4844}
4845
4846#endif  // _LIBCPP_HAS_NO_VARIADICS
4847
4848template<class _Tp, class _Up>
4849inline _LIBCPP_INLINE_VISIBILITY
4850bool
4851operator==(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4852{
4853    return __x.get() == __y.get();
4854}
4855
4856template<class _Tp, class _Up>
4857inline _LIBCPP_INLINE_VISIBILITY
4858bool
4859operator!=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4860{
4861    return !(__x == __y);
4862}
4863
4864template<class _Tp, class _Up>
4865inline _LIBCPP_INLINE_VISIBILITY
4866bool
4867operator<(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4868{
4869    typedef typename common_type<_Tp*, _Up*>::type _Vp;
4870    return less<_Vp>()(__x.get(), __y.get());
4871}
4872
4873template<class _Tp, class _Up>
4874inline _LIBCPP_INLINE_VISIBILITY
4875bool
4876operator>(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4877{
4878    return __y < __x;
4879}
4880
4881template<class _Tp, class _Up>
4882inline _LIBCPP_INLINE_VISIBILITY
4883bool
4884operator<=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4885{
4886    return !(__y < __x);
4887}
4888
4889template<class _Tp, class _Up>
4890inline _LIBCPP_INLINE_VISIBILITY
4891bool
4892operator>=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4893{
4894    return !(__x < __y);
4895}
4896
4897template<class _Tp>
4898inline _LIBCPP_INLINE_VISIBILITY
4899bool
4900operator==(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4901{
4902    return !__x;
4903}
4904
4905template<class _Tp>
4906inline _LIBCPP_INLINE_VISIBILITY
4907bool
4908operator==(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4909{
4910    return !__x;
4911}
4912
4913template<class _Tp>
4914inline _LIBCPP_INLINE_VISIBILITY
4915bool
4916operator!=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4917{
4918    return static_cast<bool>(__x);
4919}
4920
4921template<class _Tp>
4922inline _LIBCPP_INLINE_VISIBILITY
4923bool
4924operator!=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4925{
4926    return static_cast<bool>(__x);
4927}
4928
4929template<class _Tp>
4930inline _LIBCPP_INLINE_VISIBILITY
4931bool
4932operator<(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4933{
4934    return less<_Tp*>()(__x.get(), nullptr);
4935}
4936
4937template<class _Tp>
4938inline _LIBCPP_INLINE_VISIBILITY
4939bool
4940operator<(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4941{
4942    return less<_Tp*>()(nullptr, __x.get());
4943}
4944
4945template<class _Tp>
4946inline _LIBCPP_INLINE_VISIBILITY
4947bool
4948operator>(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4949{
4950    return nullptr < __x;
4951}
4952
4953template<class _Tp>
4954inline _LIBCPP_INLINE_VISIBILITY
4955bool
4956operator>(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4957{
4958    return __x < nullptr;
4959}
4960
4961template<class _Tp>
4962inline _LIBCPP_INLINE_VISIBILITY
4963bool
4964operator<=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4965{
4966    return !(nullptr < __x);
4967}
4968
4969template<class _Tp>
4970inline _LIBCPP_INLINE_VISIBILITY
4971bool
4972operator<=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4973{
4974    return !(__x < nullptr);
4975}
4976
4977template<class _Tp>
4978inline _LIBCPP_INLINE_VISIBILITY
4979bool
4980operator>=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4981{
4982    return !(__x < nullptr);
4983}
4984
4985template<class _Tp>
4986inline _LIBCPP_INLINE_VISIBILITY
4987bool
4988operator>=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4989{
4990    return !(nullptr < __x);
4991}
4992
4993template<class _Tp>
4994inline _LIBCPP_INLINE_VISIBILITY
4995void
4996swap(shared_ptr<_Tp>& __x, shared_ptr<_Tp>& __y) _NOEXCEPT
4997{
4998    __x.swap(__y);
4999}
5000
5001template<class _Tp, class _Up>
5002inline _LIBCPP_INLINE_VISIBILITY
5003typename enable_if
5004<
5005    !is_array<_Tp>::value && !is_array<_Up>::value,
5006    shared_ptr<_Tp>
5007>::type
5008static_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
5009{
5010    return shared_ptr<_Tp>(__r, static_cast<_Tp*>(__r.get()));
5011}
5012
5013template<class _Tp, class _Up>
5014inline _LIBCPP_INLINE_VISIBILITY
5015typename enable_if
5016<
5017    !is_array<_Tp>::value && !is_array<_Up>::value,
5018    shared_ptr<_Tp>
5019>::type
5020dynamic_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
5021{
5022    _Tp* __p = dynamic_cast<_Tp*>(__r.get());
5023    return __p ? shared_ptr<_Tp>(__r, __p) : shared_ptr<_Tp>();
5024}
5025
5026template<class _Tp, class _Up>
5027typename enable_if
5028<
5029    is_array<_Tp>::value == is_array<_Up>::value,
5030    shared_ptr<_Tp>
5031>::type
5032const_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
5033{
5034    typedef typename remove_extent<_Tp>::type _RTp;
5035    return shared_ptr<_Tp>(__r, const_cast<_RTp*>(__r.get()));
5036}
5037
5038#ifndef _LIBCPP_NO_RTTI
5039
5040template<class _Dp, class _Tp>
5041inline _LIBCPP_INLINE_VISIBILITY
5042_Dp*
5043get_deleter(const shared_ptr<_Tp>& __p) _NOEXCEPT
5044{
5045    return __p.template __get_deleter<_Dp>();
5046}
5047
5048#endif  // _LIBCPP_NO_RTTI
5049
5050template<class _Tp>
5051class _LIBCPP_TYPE_VIS_ONLY weak_ptr
5052{
5053public:
5054    typedef _Tp element_type;
5055private:
5056    element_type*        __ptr_;
5057    __shared_weak_count* __cntrl_;
5058
5059public:
5060    _LIBCPP_CONSTEXPR weak_ptr() _NOEXCEPT;
5061    template<class _Yp> weak_ptr(shared_ptr<_Yp> const& __r,
5062                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
5063                        _NOEXCEPT;
5064    weak_ptr(weak_ptr const& __r) _NOEXCEPT;
5065    template<class _Yp> weak_ptr(weak_ptr<_Yp> const& __r,
5066                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
5067                         _NOEXCEPT;
5068
5069#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5070    weak_ptr(weak_ptr&& __r) _NOEXCEPT;
5071    template<class _Yp> weak_ptr(weak_ptr<_Yp>&& __r,
5072                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
5073                         _NOEXCEPT;
5074#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5075    ~weak_ptr();
5076
5077    weak_ptr& operator=(weak_ptr const& __r) _NOEXCEPT;
5078    template<class _Yp>
5079        typename enable_if
5080        <
5081            is_convertible<_Yp*, element_type*>::value,
5082            weak_ptr&
5083        >::type
5084        operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT;
5085
5086#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5087
5088    weak_ptr& operator=(weak_ptr&& __r) _NOEXCEPT;
5089    template<class _Yp>
5090        typename enable_if
5091        <
5092            is_convertible<_Yp*, element_type*>::value,
5093            weak_ptr&
5094        >::type
5095        operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT;
5096
5097#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5098
5099    template<class _Yp>
5100        typename enable_if
5101        <
5102            is_convertible<_Yp*, element_type*>::value,
5103            weak_ptr&
5104        >::type
5105        operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT;
5106
5107    void swap(weak_ptr& __r) _NOEXCEPT;
5108    void reset() _NOEXCEPT;
5109
5110    _LIBCPP_INLINE_VISIBILITY
5111    long use_count() const _NOEXCEPT
5112        {return __cntrl_ ? __cntrl_->use_count() : 0;}
5113    _LIBCPP_INLINE_VISIBILITY
5114    bool expired() const _NOEXCEPT
5115        {return __cntrl_ == 0 || __cntrl_->use_count() == 0;}
5116    shared_ptr<_Tp> lock() const _NOEXCEPT;
5117    template<class _Up>
5118        _LIBCPP_INLINE_VISIBILITY
5119        bool owner_before(const shared_ptr<_Up>& __r) const
5120        {return __cntrl_ < __r.__cntrl_;}
5121    template<class _Up>
5122        _LIBCPP_INLINE_VISIBILITY
5123        bool owner_before(const weak_ptr<_Up>& __r) const
5124        {return __cntrl_ < __r.__cntrl_;}
5125
5126    template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY weak_ptr;
5127    template <class _Up> friend class _LIBCPP_TYPE_VIS_ONLY shared_ptr;
5128};
5129
5130template<class _Tp>
5131inline _LIBCPP_INLINE_VISIBILITY
5132_LIBCPP_CONSTEXPR
5133weak_ptr<_Tp>::weak_ptr() _NOEXCEPT
5134    : __ptr_(0),
5135      __cntrl_(0)
5136{
5137}
5138
5139template<class _Tp>
5140inline _LIBCPP_INLINE_VISIBILITY
5141weak_ptr<_Tp>::weak_ptr(weak_ptr const& __r) _NOEXCEPT
5142    : __ptr_(__r.__ptr_),
5143      __cntrl_(__r.__cntrl_)
5144{
5145    if (__cntrl_)
5146        __cntrl_->__add_weak();
5147}
5148
5149template<class _Tp>
5150template<class _Yp>
5151inline _LIBCPP_INLINE_VISIBILITY
5152weak_ptr<_Tp>::weak_ptr(shared_ptr<_Yp> const& __r,
5153                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
5154                         _NOEXCEPT
5155    : __ptr_(__r.__ptr_),
5156      __cntrl_(__r.__cntrl_)
5157{
5158    if (__cntrl_)
5159        __cntrl_->__add_weak();
5160}
5161
5162template<class _Tp>
5163template<class _Yp>
5164inline _LIBCPP_INLINE_VISIBILITY
5165weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp> const& __r,
5166                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
5167         _NOEXCEPT
5168    : __ptr_(__r.__ptr_),
5169      __cntrl_(__r.__cntrl_)
5170{
5171    if (__cntrl_)
5172        __cntrl_->__add_weak();
5173}
5174
5175#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5176
5177template<class _Tp>
5178inline _LIBCPP_INLINE_VISIBILITY
5179weak_ptr<_Tp>::weak_ptr(weak_ptr&& __r) _NOEXCEPT
5180    : __ptr_(__r.__ptr_),
5181      __cntrl_(__r.__cntrl_)
5182{
5183    __r.__ptr_ = 0;
5184    __r.__cntrl_ = 0;
5185}
5186
5187template<class _Tp>
5188template<class _Yp>
5189inline _LIBCPP_INLINE_VISIBILITY
5190weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp>&& __r,
5191                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
5192         _NOEXCEPT
5193    : __ptr_(__r.__ptr_),
5194      __cntrl_(__r.__cntrl_)
5195{
5196    __r.__ptr_ = 0;
5197    __r.__cntrl_ = 0;
5198}
5199
5200#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5201
5202template<class _Tp>
5203weak_ptr<_Tp>::~weak_ptr()
5204{
5205    if (__cntrl_)
5206        __cntrl_->__release_weak();
5207}
5208
5209template<class _Tp>
5210inline _LIBCPP_INLINE_VISIBILITY
5211weak_ptr<_Tp>&
5212weak_ptr<_Tp>::operator=(weak_ptr const& __r) _NOEXCEPT
5213{
5214    weak_ptr(__r).swap(*this);
5215    return *this;
5216}
5217
5218template<class _Tp>
5219template<class _Yp>
5220inline _LIBCPP_INLINE_VISIBILITY
5221typename enable_if
5222<
5223    is_convertible<_Yp*, _Tp*>::value,
5224    weak_ptr<_Tp>&
5225>::type
5226weak_ptr<_Tp>::operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT
5227{
5228    weak_ptr(__r).swap(*this);
5229    return *this;
5230}
5231
5232#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5233
5234template<class _Tp>
5235inline _LIBCPP_INLINE_VISIBILITY
5236weak_ptr<_Tp>&
5237weak_ptr<_Tp>::operator=(weak_ptr&& __r) _NOEXCEPT
5238{
5239    weak_ptr(_VSTD::move(__r)).swap(*this);
5240    return *this;
5241}
5242
5243template<class _Tp>
5244template<class _Yp>
5245inline _LIBCPP_INLINE_VISIBILITY
5246typename enable_if
5247<
5248    is_convertible<_Yp*, _Tp*>::value,
5249    weak_ptr<_Tp>&
5250>::type
5251weak_ptr<_Tp>::operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT
5252{
5253    weak_ptr(_VSTD::move(__r)).swap(*this);
5254    return *this;
5255}
5256
5257#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5258
5259template<class _Tp>
5260template<class _Yp>
5261inline _LIBCPP_INLINE_VISIBILITY
5262typename enable_if
5263<
5264    is_convertible<_Yp*, _Tp*>::value,
5265    weak_ptr<_Tp>&
5266>::type
5267weak_ptr<_Tp>::operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT
5268{
5269    weak_ptr(__r).swap(*this);
5270    return *this;
5271}
5272
5273template<class _Tp>
5274inline _LIBCPP_INLINE_VISIBILITY
5275void
5276weak_ptr<_Tp>::swap(weak_ptr& __r) _NOEXCEPT
5277{
5278    _VSTD::swap(__ptr_, __r.__ptr_);
5279    _VSTD::swap(__cntrl_, __r.__cntrl_);
5280}
5281
5282template<class _Tp>
5283inline _LIBCPP_INLINE_VISIBILITY
5284void
5285swap(weak_ptr<_Tp>& __x, weak_ptr<_Tp>& __y) _NOEXCEPT
5286{
5287    __x.swap(__y);
5288}
5289
5290template<class _Tp>
5291inline _LIBCPP_INLINE_VISIBILITY
5292void
5293weak_ptr<_Tp>::reset() _NOEXCEPT
5294{
5295    weak_ptr().swap(*this);
5296}
5297
5298template<class _Tp>
5299template<class _Yp>
5300shared_ptr<_Tp>::shared_ptr(const weak_ptr<_Yp>& __r,
5301                            typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat>::type)
5302    : __ptr_(__r.__ptr_),
5303      __cntrl_(__r.__cntrl_ ? __r.__cntrl_->lock() : __r.__cntrl_)
5304{
5305    if (__cntrl_ == 0)
5306#ifndef _LIBCPP_NO_EXCEPTIONS
5307        throw bad_weak_ptr();
5308#else
5309        assert(!"bad_weak_ptr");
5310#endif
5311}
5312
5313template<class _Tp>
5314shared_ptr<_Tp>
5315weak_ptr<_Tp>::lock() const _NOEXCEPT
5316{
5317    shared_ptr<_Tp> __r;
5318    __r.__cntrl_ = __cntrl_ ? __cntrl_->lock() : __cntrl_;
5319    if (__r.__cntrl_)
5320        __r.__ptr_ = __ptr_;
5321    return __r;
5322}
5323
5324template <class _Tp> struct owner_less;
5325
5326template <class _Tp>
5327struct _LIBCPP_TYPE_VIS_ONLY owner_less<shared_ptr<_Tp> >
5328    : binary_function<shared_ptr<_Tp>, shared_ptr<_Tp>, bool>
5329{
5330    typedef bool result_type;
5331    _LIBCPP_INLINE_VISIBILITY
5332    bool operator()(shared_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const
5333        {return __x.owner_before(__y);}
5334    _LIBCPP_INLINE_VISIBILITY
5335    bool operator()(shared_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const
5336        {return __x.owner_before(__y);}
5337    _LIBCPP_INLINE_VISIBILITY
5338    bool operator()(  weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const
5339        {return __x.owner_before(__y);}
5340};
5341
5342template <class _Tp>
5343struct _LIBCPP_TYPE_VIS_ONLY owner_less<weak_ptr<_Tp> >
5344    : binary_function<weak_ptr<_Tp>, weak_ptr<_Tp>, bool>
5345{
5346    typedef bool result_type;
5347    _LIBCPP_INLINE_VISIBILITY
5348    bool operator()(  weak_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const
5349        {return __x.owner_before(__y);}
5350    _LIBCPP_INLINE_VISIBILITY
5351    bool operator()(shared_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const
5352        {return __x.owner_before(__y);}
5353    _LIBCPP_INLINE_VISIBILITY
5354    bool operator()(  weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const
5355        {return __x.owner_before(__y);}
5356};
5357
5358template<class _Tp>
5359class _LIBCPP_TYPE_VIS_ONLY enable_shared_from_this
5360{
5361    mutable weak_ptr<_Tp> __weak_this_;
5362protected:
5363    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
5364    enable_shared_from_this() _NOEXCEPT {}
5365    _LIBCPP_INLINE_VISIBILITY
5366    enable_shared_from_this(enable_shared_from_this const&) _NOEXCEPT {}
5367    _LIBCPP_INLINE_VISIBILITY
5368    enable_shared_from_this& operator=(enable_shared_from_this const&) _NOEXCEPT
5369        {return *this;}
5370    _LIBCPP_INLINE_VISIBILITY
5371    ~enable_shared_from_this() {}
5372public:
5373    _LIBCPP_INLINE_VISIBILITY
5374    shared_ptr<_Tp> shared_from_this()
5375        {return shared_ptr<_Tp>(__weak_this_);}
5376    _LIBCPP_INLINE_VISIBILITY
5377    shared_ptr<_Tp const> shared_from_this() const
5378        {return shared_ptr<const _Tp>(__weak_this_);}
5379
5380    template <class _Up> friend class shared_ptr;
5381};
5382
5383template <class _Tp>
5384struct _LIBCPP_TYPE_VIS_ONLY hash<shared_ptr<_Tp> >
5385{
5386    typedef shared_ptr<_Tp>      argument_type;
5387    typedef size_t               result_type;
5388    _LIBCPP_INLINE_VISIBILITY
5389    result_type operator()(const argument_type& __ptr) const _NOEXCEPT
5390    {
5391        return hash<_Tp*>()(__ptr.get());
5392    }
5393};
5394
5395template<class _CharT, class _Traits, class _Yp>
5396inline _LIBCPP_INLINE_VISIBILITY
5397basic_ostream<_CharT, _Traits>&
5398operator<<(basic_ostream<_CharT, _Traits>& __os, shared_ptr<_Yp> const& __p);
5399
5400// TODO(EricWF): Enable this for both Clang and GCC. Currently it is only
5401// enabled with clang.
5402#if defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_NO_THREADS)
5403
5404class _LIBCPP_TYPE_VIS __sp_mut
5405{
5406    void* __lx;
5407public:
5408    void lock() _NOEXCEPT;
5409    void unlock() _NOEXCEPT;
5410
5411private:
5412    _LIBCPP_CONSTEXPR __sp_mut(void*) _NOEXCEPT;
5413    __sp_mut(const __sp_mut&);
5414    __sp_mut& operator=(const __sp_mut&);
5415
5416    friend _LIBCPP_FUNC_VIS __sp_mut& __get_sp_mut(const void*);
5417};
5418
5419_LIBCPP_FUNC_VIS __sp_mut& __get_sp_mut(const void*);
5420
5421template <class _Tp>
5422inline _LIBCPP_INLINE_VISIBILITY
5423bool
5424atomic_is_lock_free(const shared_ptr<_Tp>*)
5425{
5426    return false;
5427}
5428
5429template <class _Tp>
5430shared_ptr<_Tp>
5431atomic_load(const shared_ptr<_Tp>* __p)
5432{
5433    __sp_mut& __m = __get_sp_mut(__p);
5434    __m.lock();
5435    shared_ptr<_Tp> __q = *__p;
5436    __m.unlock();
5437    return __q;
5438}
5439
5440template <class _Tp>
5441inline _LIBCPP_INLINE_VISIBILITY
5442shared_ptr<_Tp>
5443atomic_load_explicit(const shared_ptr<_Tp>* __p, memory_order)
5444{
5445    return atomic_load(__p);
5446}
5447
5448template <class _Tp>
5449void
5450atomic_store(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
5451{
5452    __sp_mut& __m = __get_sp_mut(__p);
5453    __m.lock();
5454    __p->swap(__r);
5455    __m.unlock();
5456}
5457
5458template <class _Tp>
5459inline _LIBCPP_INLINE_VISIBILITY
5460void
5461atomic_store_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
5462{
5463    atomic_store(__p, __r);
5464}
5465
5466template <class _Tp>
5467shared_ptr<_Tp>
5468atomic_exchange(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
5469{
5470    __sp_mut& __m = __get_sp_mut(__p);
5471    __m.lock();
5472    __p->swap(__r);
5473    __m.unlock();
5474    return __r;
5475}
5476
5477template <class _Tp>
5478inline _LIBCPP_INLINE_VISIBILITY
5479shared_ptr<_Tp>
5480atomic_exchange_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
5481{
5482    return atomic_exchange(__p, __r);
5483}
5484
5485template <class _Tp>
5486bool
5487atomic_compare_exchange_strong(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
5488{
5489    __sp_mut& __m = __get_sp_mut(__p);
5490    __m.lock();
5491    if (__p->__owner_equivalent(*__v))
5492    {
5493        *__p = __w;
5494        __m.unlock();
5495        return true;
5496    }
5497    *__v = *__p;
5498    __m.unlock();
5499    return false;
5500}
5501
5502template <class _Tp>
5503inline _LIBCPP_INLINE_VISIBILITY
5504bool
5505atomic_compare_exchange_weak(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
5506{
5507    return atomic_compare_exchange_strong(__p, __v, __w);
5508}
5509
5510template <class _Tp>
5511inline _LIBCPP_INLINE_VISIBILITY
5512bool
5513atomic_compare_exchange_strong_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
5514                                        shared_ptr<_Tp> __w, memory_order, memory_order)
5515{
5516    return atomic_compare_exchange_strong(__p, __v, __w);
5517}
5518
5519template <class _Tp>
5520inline _LIBCPP_INLINE_VISIBILITY
5521bool
5522atomic_compare_exchange_weak_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
5523                                      shared_ptr<_Tp> __w, memory_order, memory_order)
5524{
5525    return atomic_compare_exchange_weak(__p, __v, __w);
5526}
5527
5528#endif  // defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_NO_THREADS)
5529
5530//enum class
5531struct _LIBCPP_TYPE_VIS pointer_safety
5532{
5533    enum __lx
5534    {
5535        relaxed,
5536        preferred,
5537        strict
5538    };
5539
5540    __lx __v_;
5541
5542    _LIBCPP_INLINE_VISIBILITY
5543    pointer_safety(__lx __v) : __v_(__v) {}
5544    _LIBCPP_INLINE_VISIBILITY
5545    operator int() const {return __v_;}
5546};
5547
5548_LIBCPP_FUNC_VIS void declare_reachable(void* __p);
5549_LIBCPP_FUNC_VIS void declare_no_pointers(char* __p, size_t __n);
5550_LIBCPP_FUNC_VIS void undeclare_no_pointers(char* __p, size_t __n);
5551_LIBCPP_FUNC_VIS pointer_safety get_pointer_safety() _NOEXCEPT;
5552_LIBCPP_FUNC_VIS void* __undeclare_reachable(void* __p);
5553
5554template <class _Tp>
5555inline _LIBCPP_INLINE_VISIBILITY
5556_Tp*
5557undeclare_reachable(_Tp* __p)
5558{
5559    return static_cast<_Tp*>(__undeclare_reachable(__p));
5560}
5561
5562_LIBCPP_FUNC_VIS void* align(size_t __align, size_t __sz, void*& __ptr, size_t& __space);
5563
5564// --- Helper for container swap --
5565template <typename _Alloc>
5566_LIBCPP_INLINE_VISIBILITY
5567void __swap_allocator(_Alloc & __a1, _Alloc & __a2)
5568#if _LIBCPP_STD_VER >= 14
5569    _NOEXCEPT
5570#else
5571    _NOEXCEPT_(__is_nothrow_swappable<_Alloc>::value)
5572#endif
5573{
5574    __swap_allocator(__a1, __a2,
5575      integral_constant<bool, _VSTD::allocator_traits<_Alloc>::propagate_on_container_swap::value>());
5576}
5577
5578template <typename _Alloc>
5579_LIBCPP_INLINE_VISIBILITY
5580void __swap_allocator(_Alloc & __a1, _Alloc & __a2, true_type)
5581#if _LIBCPP_STD_VER >= 14
5582    _NOEXCEPT
5583#else
5584    _NOEXCEPT_(__is_nothrow_swappable<_Alloc>::value)
5585#endif
5586{
5587    using _VSTD::swap;
5588    swap(__a1, __a2);
5589}
5590
5591template <typename _Alloc>
5592_LIBCPP_INLINE_VISIBILITY
5593void __swap_allocator(_Alloc &, _Alloc &, false_type) _NOEXCEPT {}
5594
5595template <typename _Alloc, typename _Traits=allocator_traits<_Alloc> >
5596struct __noexcept_move_assign_container : public integral_constant<bool,
5597    _Traits::propagate_on_container_move_assignment::value
5598#if _LIBCPP_STD_VER > 14
5599        || _Traits::is_always_equal::value
5600#else
5601        && is_nothrow_move_assignable<_Alloc>::value
5602#endif
5603    > {};
5604
5605_LIBCPP_END_NAMESPACE_STD
5606
5607#endif  // _LIBCPP_MEMORY
5608