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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;
167template <class T> T* addressof(const T&& r) noexcept = delete;
168
169template <class InputIterator, class ForwardIterator>
170ForwardIterator
171uninitialized_copy(InputIterator first, InputIterator last, ForwardIterator result);
172
173template <class InputIterator, class Size, class ForwardIterator>
174ForwardIterator
175uninitialized_copy_n(InputIterator first, Size n, ForwardIterator result);
176
177template <class ForwardIterator, class T>
178void uninitialized_fill(ForwardIterator first, ForwardIterator last, const T& x);
179
180template <class ForwardIterator, class Size, class T>
181ForwardIterator
182uninitialized_fill_n(ForwardIterator first, Size n, const T& x);
183
184template <class T>
185void destroy_at(T* location);
186
187template <class ForwardIterator>
188 void destroy(ForwardIterator first, ForwardIterator last);
189
190template <class ForwardIterator, class Size>
191 ForwardIterator destroy_n(ForwardIterator first, Size n);
192
193template <class InputIterator, class ForwardIterator>
194 ForwardIterator uninitialized_move(InputIterator first, InputIterator last, ForwardIterator result);
195
196template <class InputIterator, class Size, class ForwardIterator>
197 pair<InputIterator,ForwardIterator> uninitialized_move_n(InputIterator first, Size n, ForwardIterator result);
198
199template <class ForwardIterator>
200 void uninitialized_value_construct(ForwardIterator first, ForwardIterator last);
201
202template <class ForwardIterator, class Size>
203 ForwardIterator uninitialized_value_construct_n(ForwardIterator first, Size n);
204
205template <class ForwardIterator>
206 void uninitialized_default_construct(ForwardIterator first, ForwardIterator last);
207
208template <class ForwardIterator, class Size>
209 ForwardIterator uninitialized_default_construct_n(ForwardIterator first, Size n);
210
211template <class Y> struct auto_ptr_ref {};      // removed in C++17
212
213template<class X>
214class auto_ptr                                  // removed in C++17
215{
216public:
217    typedef X element_type;
218
219    explicit auto_ptr(X* p =0) throw();
220    auto_ptr(auto_ptr&) throw();
221    template<class Y> auto_ptr(auto_ptr<Y>&) throw();
222    auto_ptr& operator=(auto_ptr&) throw();
223    template<class Y> auto_ptr& operator=(auto_ptr<Y>&) throw();
224    auto_ptr& operator=(auto_ptr_ref<X> r) throw();
225    ~auto_ptr() throw();
226
227    typename add_lvalue_reference<X>::type operator*() const throw();
228    X* operator->() const throw();
229    X* get() const throw();
230    X* release() throw();
231    void reset(X* p =0) throw();
232
233    auto_ptr(auto_ptr_ref<X>) throw();
234    template<class Y> operator auto_ptr_ref<Y>() throw();
235    template<class Y> operator auto_ptr<Y>() throw();
236};
237
238template <class T>
239struct default_delete
240{
241    constexpr default_delete() noexcept = default;
242    template <class U> default_delete(const default_delete<U>&) noexcept;
243
244    void operator()(T*) const noexcept;
245};
246
247template <class T>
248struct default_delete<T[]>
249{
250    constexpr default_delete() noexcept = default;
251    void operator()(T*) const noexcept;
252    template <class U> void operator()(U*) const = delete;
253};
254
255template <class T, class D = default_delete<T>>
256class unique_ptr
257{
258public:
259    typedef see below pointer;
260    typedef T element_type;
261    typedef D deleter_type;
262
263    // constructors
264    constexpr unique_ptr() noexcept;
265    explicit unique_ptr(pointer p) noexcept;
266    unique_ptr(pointer p, see below d1) noexcept;
267    unique_ptr(pointer p, see below d2) noexcept;
268    unique_ptr(unique_ptr&& u) noexcept;
269    unique_ptr(nullptr_t) noexcept : unique_ptr() { }
270    template <class U, class E>
271        unique_ptr(unique_ptr<U, E>&& u) noexcept;
272    template <class U>
273        unique_ptr(auto_ptr<U>&& u) noexcept;       // removed in C++17
274
275    // destructor
276    ~unique_ptr();
277
278    // assignment
279    unique_ptr& operator=(unique_ptr&& u) noexcept;
280    template <class U, class E> unique_ptr& operator=(unique_ptr<U, E>&& u) noexcept;
281    unique_ptr& operator=(nullptr_t) noexcept;
282
283    // observers
284    typename add_lvalue_reference<T>::type operator*() const;
285    pointer operator->() const noexcept;
286    pointer get() const noexcept;
287    deleter_type& get_deleter() noexcept;
288    const deleter_type& get_deleter() const noexcept;
289    explicit operator bool() const noexcept;
290
291    // modifiers
292    pointer release() noexcept;
293    void reset(pointer p = pointer()) noexcept;
294    void swap(unique_ptr& u) noexcept;
295};
296
297template <class T, class D>
298class unique_ptr<T[], D>
299{
300public:
301    typedef implementation-defined pointer;
302    typedef T element_type;
303    typedef D deleter_type;
304
305    // constructors
306    constexpr unique_ptr() noexcept;
307    explicit unique_ptr(pointer p) noexcept;
308    unique_ptr(pointer p, see below d) noexcept;
309    unique_ptr(pointer p, see below d) noexcept;
310    unique_ptr(unique_ptr&& u) noexcept;
311    unique_ptr(nullptr_t) noexcept : unique_ptr() { }
312
313    // destructor
314    ~unique_ptr();
315
316    // assignment
317    unique_ptr& operator=(unique_ptr&& u) noexcept;
318    unique_ptr& operator=(nullptr_t) noexcept;
319
320    // observers
321    T& operator[](size_t i) const;
322    pointer get() const noexcept;
323    deleter_type& get_deleter() noexcept;
324    const deleter_type& get_deleter() const noexcept;
325    explicit operator bool() const noexcept;
326
327    // modifiers
328    pointer release() noexcept;
329    void reset(pointer p = pointer()) noexcept;
330    void reset(nullptr_t) noexcept;
331    template <class U> void reset(U) = delete;
332    void swap(unique_ptr& u) noexcept;
333};
334
335template <class T, class D>
336    void swap(unique_ptr<T, D>& x, unique_ptr<T, D>& y) noexcept;
337
338template <class T1, class D1, class T2, class D2>
339    bool operator==(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
340template <class T1, class D1, class T2, class D2>
341    bool operator!=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
342template <class T1, class D1, class T2, class D2>
343    bool operator<(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
344template <class T1, class D1, class T2, class D2>
345    bool operator<=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
346template <class T1, class D1, class T2, class D2>
347    bool operator>(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
348template <class T1, class D1, class T2, class D2>
349    bool operator>=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
350
351template <class T, class D>
352    bool operator==(const unique_ptr<T, D>& x, nullptr_t) noexcept;
353template <class T, class D>
354    bool operator==(nullptr_t, const unique_ptr<T, D>& y) noexcept;
355template <class T, class D>
356    bool operator!=(const unique_ptr<T, D>& x, nullptr_t) noexcept;
357template <class T, class D>
358    bool operator!=(nullptr_t, const unique_ptr<T, D>& y) noexcept;
359
360template <class T, class D>
361    bool operator<(const unique_ptr<T, D>& x, nullptr_t);
362template <class T, class D>
363    bool operator<(nullptr_t, const unique_ptr<T, D>& y);
364template <class T, class D>
365    bool operator<=(const unique_ptr<T, D>& x, nullptr_t);
366template <class T, class D>
367    bool operator<=(nullptr_t, const unique_ptr<T, D>& y);
368template <class T, class D>
369    bool operator>(const unique_ptr<T, D>& x, nullptr_t);
370template <class T, class D>
371    bool operator>(nullptr_t, const unique_ptr<T, D>& y);
372template <class T, class D>
373    bool operator>=(const unique_ptr<T, D>& x, nullptr_t);
374template <class T, class D>
375    bool operator>=(nullptr_t, const unique_ptr<T, D>& y);
376
377class bad_weak_ptr
378    : public std::exception
379{
380    bad_weak_ptr() noexcept;
381};
382
383template<class T, class... Args> unique_ptr<T> make_unique(Args&&... args);     // C++14
384template<class T>                unique_ptr<T> make_unique(size_t n);           // C++14
385template<class T, class... Args> unspecified   make_unique(Args&&...) = delete; // C++14, T == U[N]
386
387template<class T>
388class shared_ptr
389{
390public:
391    typedef T element_type;
392    typedef weak_ptr<T> weak_type; // C++17
393
394    // constructors:
395    constexpr shared_ptr() noexcept;
396    template<class Y> explicit shared_ptr(Y* p);
397    template<class Y, class D> shared_ptr(Y* p, D d);
398    template<class Y, class D, class A> shared_ptr(Y* p, D d, A a);
399    template <class D> shared_ptr(nullptr_t p, D d);
400    template <class D, class A> shared_ptr(nullptr_t p, D d, A a);
401    template<class Y> shared_ptr(const shared_ptr<Y>& r, T *p) noexcept;
402    shared_ptr(const shared_ptr& r) noexcept;
403    template<class Y> shared_ptr(const shared_ptr<Y>& r) noexcept;
404    shared_ptr(shared_ptr&& r) noexcept;
405    template<class Y> shared_ptr(shared_ptr<Y>&& r) noexcept;
406    template<class Y> explicit shared_ptr(const weak_ptr<Y>& r);
407    template<class Y> shared_ptr(auto_ptr<Y>&& r);          // removed in C++17
408    template <class Y, class D> shared_ptr(unique_ptr<Y, D>&& r);
409    shared_ptr(nullptr_t) : shared_ptr() { }
410
411    // destructor:
412    ~shared_ptr();
413
414    // assignment:
415    shared_ptr& operator=(const shared_ptr& r) noexcept;
416    template<class Y> shared_ptr& operator=(const shared_ptr<Y>& r) noexcept;
417    shared_ptr& operator=(shared_ptr&& r) noexcept;
418    template<class Y> shared_ptr& operator=(shared_ptr<Y>&& r);
419    template<class Y> shared_ptr& operator=(auto_ptr<Y>&& r); // removed in C++17
420    template <class Y, class D> shared_ptr& operator=(unique_ptr<Y, D>&& r);
421
422    // modifiers:
423    void swap(shared_ptr& r) noexcept;
424    void reset() noexcept;
425    template<class Y> void reset(Y* p);
426    template<class Y, class D> void reset(Y* p, D d);
427    template<class Y, class D, class A> void reset(Y* p, D d, A a);
428
429    // observers:
430    T* get() const noexcept;
431    T& operator*() const noexcept;
432    T* operator->() const noexcept;
433    long use_count() const noexcept;
434    bool unique() const noexcept;
435    explicit operator bool() const noexcept;
436    template<class U> bool owner_before(shared_ptr<U> const& b) const;
437    template<class U> bool owner_before(weak_ptr<U> const& b) const;
438};
439
440// shared_ptr comparisons:
441template<class T, class U>
442    bool operator==(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
443template<class T, class U>
444    bool operator!=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
445template<class T, class U>
446    bool operator<(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
447template<class T, class U>
448    bool operator>(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
449template<class T, class U>
450    bool operator<=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
451template<class T, class U>
452    bool operator>=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
453
454template <class T>
455    bool operator==(const shared_ptr<T>& x, nullptr_t) noexcept;
456template <class T>
457    bool operator==(nullptr_t, const shared_ptr<T>& y) noexcept;
458template <class T>
459    bool operator!=(const shared_ptr<T>& x, nullptr_t) noexcept;
460template <class T>
461    bool operator!=(nullptr_t, const shared_ptr<T>& y) noexcept;
462template <class T>
463    bool operator<(const shared_ptr<T>& x, nullptr_t) noexcept;
464template <class T>
465bool operator<(nullptr_t, const shared_ptr<T>& y) noexcept;
466template <class T>
467    bool operator<=(const shared_ptr<T>& x, nullptr_t) noexcept;
468template <class T>
469    bool operator<=(nullptr_t, const shared_ptr<T>& y) noexcept;
470template <class T>
471    bool operator>(const shared_ptr<T>& x, nullptr_t) noexcept;
472template <class T>
473    bool operator>(nullptr_t, const shared_ptr<T>& y) noexcept;
474template <class T>
475    bool operator>=(const shared_ptr<T>& x, nullptr_t) noexcept;
476template <class T>
477    bool operator>=(nullptr_t, const shared_ptr<T>& y) noexcept;
478
479// shared_ptr specialized algorithms:
480template<class T> void swap(shared_ptr<T>& a, shared_ptr<T>& b) noexcept;
481
482// shared_ptr casts:
483template<class T, class U>
484    shared_ptr<T> static_pointer_cast(shared_ptr<U> const& r) noexcept;
485template<class T, class U>
486    shared_ptr<T> dynamic_pointer_cast(shared_ptr<U> const& r) noexcept;
487template<class T, class U>
488    shared_ptr<T> const_pointer_cast(shared_ptr<U> const& r) noexcept;
489
490// shared_ptr I/O:
491template<class E, class T, class Y>
492    basic_ostream<E, T>& operator<< (basic_ostream<E, T>& os, shared_ptr<Y> const& p);
493
494// shared_ptr get_deleter:
495template<class D, class T> D* get_deleter(shared_ptr<T> const& p) noexcept;
496
497template<class T, class... Args>
498    shared_ptr<T> make_shared(Args&&... args);
499template<class T, class A, class... Args>
500    shared_ptr<T> allocate_shared(const A& a, Args&&... args);
501
502template<class T>
503class weak_ptr
504{
505public:
506    typedef T element_type;
507
508    // constructors
509    constexpr weak_ptr() noexcept;
510    template<class Y> weak_ptr(shared_ptr<Y> const& r) noexcept;
511    weak_ptr(weak_ptr const& r) noexcept;
512    template<class Y> weak_ptr(weak_ptr<Y> const& r) noexcept;
513    weak_ptr(weak_ptr&& r) noexcept;                      // C++14
514    template<class Y> weak_ptr(weak_ptr<Y>&& r) noexcept; // C++14
515
516    // destructor
517    ~weak_ptr();
518
519    // assignment
520    weak_ptr& operator=(weak_ptr const& r) noexcept;
521    template<class Y> weak_ptr& operator=(weak_ptr<Y> const& r) noexcept;
522    template<class Y> weak_ptr& operator=(shared_ptr<Y> const& r) noexcept;
523    weak_ptr& operator=(weak_ptr&& r) noexcept;                      // C++14
524    template<class Y> weak_ptr& operator=(weak_ptr<Y>&& r) noexcept; // C++14
525
526    // modifiers
527    void swap(weak_ptr& r) noexcept;
528    void reset() noexcept;
529
530    // observers
531    long use_count() const noexcept;
532    bool expired() const noexcept;
533    shared_ptr<T> lock() const noexcept;
534    template<class U> bool owner_before(shared_ptr<U> const& b) const;
535    template<class U> bool owner_before(weak_ptr<U> const& b) const;
536};
537
538// weak_ptr specialized algorithms:
539template<class T> void swap(weak_ptr<T>& a, weak_ptr<T>& b) noexcept;
540
541// class owner_less:
542template<class T> struct owner_less;
543
544template<class T>
545struct owner_less<shared_ptr<T>>
546    : binary_function<shared_ptr<T>, shared_ptr<T>, bool>
547{
548    typedef bool result_type;
549    bool operator()(shared_ptr<T> const&, shared_ptr<T> const&) const;
550    bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const;
551    bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const;
552};
553
554template<class T>
555struct owner_less<weak_ptr<T>>
556    : binary_function<weak_ptr<T>, weak_ptr<T>, bool>
557{
558    typedef bool result_type;
559    bool operator()(weak_ptr<T> const&, weak_ptr<T> const&) const;
560    bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const;
561    bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const;
562};
563
564template<class T>
565class enable_shared_from_this
566{
567protected:
568    constexpr enable_shared_from_this() noexcept;
569    enable_shared_from_this(enable_shared_from_this const&) noexcept;
570    enable_shared_from_this& operator=(enable_shared_from_this const&) noexcept;
571    ~enable_shared_from_this();
572public:
573    shared_ptr<T> shared_from_this();
574    shared_ptr<T const> shared_from_this() const;
575};
576
577template<class T>
578    bool atomic_is_lock_free(const shared_ptr<T>* p);
579template<class T>
580    shared_ptr<T> atomic_load(const shared_ptr<T>* p);
581template<class T>
582    shared_ptr<T> atomic_load_explicit(const shared_ptr<T>* p, memory_order mo);
583template<class T>
584    void atomic_store(shared_ptr<T>* p, shared_ptr<T> r);
585template<class T>
586    void atomic_store_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
587template<class T>
588    shared_ptr<T> atomic_exchange(shared_ptr<T>* p, shared_ptr<T> r);
589template<class T>
590    shared_ptr<T>
591    atomic_exchange_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
592template<class T>
593    bool
594    atomic_compare_exchange_weak(shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
595template<class T>
596    bool
597    atomic_compare_exchange_strong( shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
598template<class T>
599    bool
600    atomic_compare_exchange_weak_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
601                                          shared_ptr<T> w, memory_order success,
602                                          memory_order failure);
603template<class T>
604    bool
605    atomic_compare_exchange_strong_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
606                                            shared_ptr<T> w, memory_order success,
607                                            memory_order failure);
608// Hash support
609template <class T> struct hash;
610template <class T, class D> struct hash<unique_ptr<T, D> >;
611template <class T> struct hash<shared_ptr<T> >;
612
613// Pointer safety
614enum class pointer_safety { relaxed, preferred, strict };
615void declare_reachable(void *p);
616template <class T> T *undeclare_reachable(T *p);
617void declare_no_pointers(char *p, size_t n);
618void undeclare_no_pointers(char *p, size_t n);
619pointer_safety get_pointer_safety() noexcept;
620
621void* align(size_t alignment, size_t size, void*& ptr, size_t& space);
622
623}  // std
624
625*/
626
627#include <__config>
628#include <type_traits>
629#include <typeinfo>
630#include <cstddef>
631#include <cstdint>
632#include <new>
633#include <utility>
634#include <limits>
635#include <iterator>
636#include <__functional_base>
637#include <iosfwd>
638#include <tuple>
639#include <stdexcept>
640#include <cstring>
641
642#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
643#  include <atomic>
644#endif
645
646#include <__undef_min_max>
647
648#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
649#pragma GCC system_header
650#endif
651
652_LIBCPP_BEGIN_NAMESPACE_STD
653
654template <class _ValueType>
655inline _LIBCPP_ALWAYS_INLINE
656_ValueType __libcpp_relaxed_load(_ValueType const* __value) {
657#if !defined(_LIBCPP_HAS_NO_THREADS) && \
658    defined(__ATOMIC_RELAXED) &&        \
659    (__has_builtin(__atomic_load_n) || _GNUC_VER >= 407)
660    return __atomic_load_n(__value, __ATOMIC_RELAXED);
661#else
662    return *__value;
663#endif
664}
665
666template <class _ValueType>
667inline _LIBCPP_ALWAYS_INLINE
668_ValueType __libcpp_acquire_load(_ValueType const* __value) {
669#if !defined(_LIBCPP_HAS_NO_THREADS) && \
670    defined(__ATOMIC_ACQUIRE) &&        \
671    (__has_builtin(__atomic_load_n) || _GNUC_VER >= 407)
672    return __atomic_load_n(__value, __ATOMIC_ACQUIRE);
673#else
674    return *__value;
675#endif
676}
677
678// addressof moved to <type_traits>
679
680template <class _Tp> class allocator;
681
682template <>
683class _LIBCPP_TEMPLATE_VIS allocator<void>
684{
685public:
686    typedef void*             pointer;
687    typedef const void*       const_pointer;
688    typedef void              value_type;
689
690    template <class _Up> struct rebind {typedef allocator<_Up> other;};
691};
692
693template <>
694class _LIBCPP_TEMPLATE_VIS allocator<const void>
695{
696public:
697    typedef const void*       pointer;
698    typedef const void*       const_pointer;
699    typedef const void        value_type;
700
701    template <class _Up> struct rebind {typedef allocator<_Up> other;};
702};
703
704// pointer_traits
705
706template <class _Tp>
707struct __has_element_type
708{
709private:
710    struct __two {char __lx; char __lxx;};
711    template <class _Up> static __two __test(...);
712    template <class _Up> static char __test(typename _Up::element_type* = 0);
713public:
714    static const bool value = sizeof(__test<_Tp>(0)) == 1;
715};
716
717template <class _Ptr, bool = __has_element_type<_Ptr>::value>
718struct __pointer_traits_element_type;
719
720template <class _Ptr>
721struct __pointer_traits_element_type<_Ptr, true>
722{
723    typedef typename _Ptr::element_type type;
724};
725
726#ifndef _LIBCPP_HAS_NO_VARIADICS
727
728template <template <class, class...> class _Sp, class _Tp, class ..._Args>
729struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, true>
730{
731    typedef typename _Sp<_Tp, _Args...>::element_type type;
732};
733
734template <template <class, class...> class _Sp, class _Tp, class ..._Args>
735struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, false>
736{
737    typedef _Tp type;
738};
739
740#else  // _LIBCPP_HAS_NO_VARIADICS
741
742template <template <class> class _Sp, class _Tp>
743struct __pointer_traits_element_type<_Sp<_Tp>, true>
744{
745    typedef typename _Sp<_Tp>::element_type type;
746};
747
748template <template <class> class _Sp, class _Tp>
749struct __pointer_traits_element_type<_Sp<_Tp>, false>
750{
751    typedef _Tp type;
752};
753
754template <template <class, class> class _Sp, class _Tp, class _A0>
755struct __pointer_traits_element_type<_Sp<_Tp, _A0>, true>
756{
757    typedef typename _Sp<_Tp, _A0>::element_type type;
758};
759
760template <template <class, class> class _Sp, class _Tp, class _A0>
761struct __pointer_traits_element_type<_Sp<_Tp, _A0>, false>
762{
763    typedef _Tp type;
764};
765
766template <template <class, class, class> class _Sp, class _Tp, class _A0, class _A1>
767struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1>, true>
768{
769    typedef typename _Sp<_Tp, _A0, _A1>::element_type type;
770};
771
772template <template <class, class, class> class _Sp, class _Tp, class _A0, class _A1>
773struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1>, false>
774{
775    typedef _Tp type;
776};
777
778template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
779                                                           class _A1, class _A2>
780struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1, _A2>, true>
781{
782    typedef typename _Sp<_Tp, _A0, _A1, _A2>::element_type type;
783};
784
785template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
786                                                           class _A1, class _A2>
787struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1, _A2>, false>
788{
789    typedef _Tp type;
790};
791
792#endif  // _LIBCPP_HAS_NO_VARIADICS
793
794template <class _Tp>
795struct __has_difference_type
796{
797private:
798    struct __two {char __lx; char __lxx;};
799    template <class _Up> static __two __test(...);
800    template <class _Up> static char __test(typename _Up::difference_type* = 0);
801public:
802    static const bool value = sizeof(__test<_Tp>(0)) == 1;
803};
804
805template <class _Ptr, bool = __has_difference_type<_Ptr>::value>
806struct __pointer_traits_difference_type
807{
808    typedef ptrdiff_t type;
809};
810
811template <class _Ptr>
812struct __pointer_traits_difference_type<_Ptr, true>
813{
814    typedef typename _Ptr::difference_type type;
815};
816
817template <class _Tp, class _Up>
818struct __has_rebind
819{
820private:
821    struct __two {char __lx; char __lxx;};
822    template <class _Xp> static __two __test(...);
823    template <class _Xp> static char __test(typename _Xp::template rebind<_Up>* = 0);
824public:
825    static const bool value = sizeof(__test<_Tp>(0)) == 1;
826};
827
828template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
829struct __pointer_traits_rebind
830{
831#ifndef _LIBCPP_CXX03_LANG
832    typedef typename _Tp::template rebind<_Up> type;
833#else
834    typedef typename _Tp::template rebind<_Up>::other type;
835#endif
836};
837
838#ifndef _LIBCPP_HAS_NO_VARIADICS
839
840template <template <class, class...> class _Sp, class _Tp, class ..._Args, class _Up>
841struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, true>
842{
843#ifndef _LIBCPP_CXX03_LANG
844    typedef typename _Sp<_Tp, _Args...>::template rebind<_Up> type;
845#else
846    typedef typename _Sp<_Tp, _Args...>::template rebind<_Up>::other type;
847#endif
848};
849
850template <template <class, class...> class _Sp, class _Tp, class ..._Args, class _Up>
851struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, false>
852{
853    typedef _Sp<_Up, _Args...> type;
854};
855
856#else  // _LIBCPP_HAS_NO_VARIADICS
857
858template <template <class> class _Sp, class _Tp, class _Up>
859struct __pointer_traits_rebind<_Sp<_Tp>, _Up, true>
860{
861#ifndef _LIBCPP_CXX03_LANG
862    typedef typename _Sp<_Tp>::template rebind<_Up> type;
863#else
864    typedef typename _Sp<_Tp>::template rebind<_Up>::other type;
865#endif
866};
867
868template <template <class> class _Sp, class _Tp, class _Up>
869struct __pointer_traits_rebind<_Sp<_Tp>, _Up, false>
870{
871    typedef _Sp<_Up> type;
872};
873
874template <template <class, class> class _Sp, class _Tp, class _A0, class _Up>
875struct __pointer_traits_rebind<_Sp<_Tp, _A0>, _Up, true>
876{
877#ifndef _LIBCPP_CXX03_LANG
878    typedef typename _Sp<_Tp, _A0>::template rebind<_Up> type;
879#else
880    typedef typename _Sp<_Tp, _A0>::template rebind<_Up>::other type;
881#endif
882};
883
884template <template <class, class> class _Sp, class _Tp, class _A0, class _Up>
885struct __pointer_traits_rebind<_Sp<_Tp, _A0>, _Up, false>
886{
887    typedef _Sp<_Up, _A0> type;
888};
889
890template <template <class, class, class> class _Sp, class _Tp, class _A0,
891                                         class _A1, class _Up>
892struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1>, _Up, true>
893{
894#ifndef _LIBCPP_CXX03_LANG
895    typedef typename _Sp<_Tp, _A0, _A1>::template rebind<_Up> type;
896#else
897    typedef typename _Sp<_Tp, _A0, _A1>::template rebind<_Up>::other type;
898#endif
899};
900
901template <template <class, class, class> class _Sp, class _Tp, class _A0,
902                                         class _A1, class _Up>
903struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1>, _Up, false>
904{
905    typedef _Sp<_Up, _A0, _A1> type;
906};
907
908template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
909                                                class _A1, class _A2, class _Up>
910struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1, _A2>, _Up, true>
911{
912#ifndef _LIBCPP_CXX03_LANG
913    typedef typename _Sp<_Tp, _A0, _A1, _A2>::template rebind<_Up> type;
914#else
915    typedef typename _Sp<_Tp, _A0, _A1, _A2>::template rebind<_Up>::other type;
916#endif
917};
918
919template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
920                                                class _A1, class _A2, class _Up>
921struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1, _A2>, _Up, false>
922{
923    typedef _Sp<_Up, _A0, _A1, _A2> type;
924};
925
926#endif  // _LIBCPP_HAS_NO_VARIADICS
927
928template <class _Ptr>
929struct _LIBCPP_TEMPLATE_VIS pointer_traits
930{
931    typedef _Ptr                                                     pointer;
932    typedef typename __pointer_traits_element_type<pointer>::type    element_type;
933    typedef typename __pointer_traits_difference_type<pointer>::type difference_type;
934
935#ifndef _LIBCPP_CXX03_LANG
936    template <class _Up> using rebind = typename __pointer_traits_rebind<pointer, _Up>::type;
937#else
938    template <class _Up> struct rebind
939        {typedef typename __pointer_traits_rebind<pointer, _Up>::type other;};
940#endif  // _LIBCPP_CXX03_LANG
941
942private:
943    struct __nat {};
944public:
945    _LIBCPP_INLINE_VISIBILITY
946    static pointer pointer_to(typename conditional<is_void<element_type>::value,
947                                           __nat, element_type>::type& __r)
948        {return pointer::pointer_to(__r);}
949};
950
951template <class _Tp>
952struct _LIBCPP_TEMPLATE_VIS pointer_traits<_Tp*>
953{
954    typedef _Tp*      pointer;
955    typedef _Tp       element_type;
956    typedef ptrdiff_t difference_type;
957
958#ifndef _LIBCPP_CXX03_LANG
959    template <class _Up> using rebind = _Up*;
960#else
961    template <class _Up> struct rebind {typedef _Up* other;};
962#endif
963
964private:
965    struct __nat {};
966public:
967    _LIBCPP_INLINE_VISIBILITY
968    static pointer pointer_to(typename conditional<is_void<element_type>::value,
969                                      __nat, element_type>::type& __r) _NOEXCEPT
970        {return _VSTD::addressof(__r);}
971};
972
973template <class _From, class _To>
974struct __rebind_pointer {
975#ifndef _LIBCPP_CXX03_LANG
976    typedef typename pointer_traits<_From>::template rebind<_To>        type;
977#else
978    typedef typename pointer_traits<_From>::template rebind<_To>::other type;
979#endif
980};
981
982// allocator_traits
983
984namespace __has_pointer_type_imp
985{
986    template <class _Up> static __two __test(...);
987    template <class _Up> static char __test(typename _Up::pointer* = 0);
988}
989
990template <class _Tp>
991struct __has_pointer_type
992    : public integral_constant<bool, sizeof(__has_pointer_type_imp::__test<_Tp>(0)) == 1>
993{
994};
995
996namespace __pointer_type_imp
997{
998
999template <class _Tp, class _Dp, bool = __has_pointer_type<_Dp>::value>
1000struct __pointer_type
1001{
1002    typedef typename _Dp::pointer type;
1003};
1004
1005template <class _Tp, class _Dp>
1006struct __pointer_type<_Tp, _Dp, false>
1007{
1008    typedef _Tp* type;
1009};
1010
1011}  // __pointer_type_imp
1012
1013template <class _Tp, class _Dp>
1014struct __pointer_type
1015{
1016    typedef typename __pointer_type_imp::__pointer_type<_Tp, typename remove_reference<_Dp>::type>::type type;
1017};
1018
1019template <class _Tp>
1020struct __has_const_pointer
1021{
1022private:
1023    struct __two {char __lx; char __lxx;};
1024    template <class _Up> static __two __test(...);
1025    template <class _Up> static char __test(typename _Up::const_pointer* = 0);
1026public:
1027    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1028};
1029
1030template <class _Tp, class _Ptr, class _Alloc, bool = __has_const_pointer<_Alloc>::value>
1031struct __const_pointer
1032{
1033    typedef typename _Alloc::const_pointer type;
1034};
1035
1036template <class _Tp, class _Ptr, class _Alloc>
1037struct __const_pointer<_Tp, _Ptr, _Alloc, false>
1038{
1039#ifndef _LIBCPP_CXX03_LANG
1040    typedef typename pointer_traits<_Ptr>::template rebind<const _Tp> type;
1041#else
1042    typedef typename pointer_traits<_Ptr>::template rebind<const _Tp>::other type;
1043#endif
1044};
1045
1046template <class _Tp>
1047struct __has_void_pointer
1048{
1049private:
1050    struct __two {char __lx; char __lxx;};
1051    template <class _Up> static __two __test(...);
1052    template <class _Up> static char __test(typename _Up::void_pointer* = 0);
1053public:
1054    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1055};
1056
1057template <class _Ptr, class _Alloc, bool = __has_void_pointer<_Alloc>::value>
1058struct __void_pointer
1059{
1060    typedef typename _Alloc::void_pointer type;
1061};
1062
1063template <class _Ptr, class _Alloc>
1064struct __void_pointer<_Ptr, _Alloc, false>
1065{
1066#ifndef _LIBCPP_CXX03_LANG
1067    typedef typename pointer_traits<_Ptr>::template rebind<void> type;
1068#else
1069    typedef typename pointer_traits<_Ptr>::template rebind<void>::other type;
1070#endif
1071};
1072
1073template <class _Tp>
1074struct __has_const_void_pointer
1075{
1076private:
1077    struct __two {char __lx; char __lxx;};
1078    template <class _Up> static __two __test(...);
1079    template <class _Up> static char __test(typename _Up::const_void_pointer* = 0);
1080public:
1081    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1082};
1083
1084template <class _Ptr, class _Alloc, bool = __has_const_void_pointer<_Alloc>::value>
1085struct __const_void_pointer
1086{
1087    typedef typename _Alloc::const_void_pointer type;
1088};
1089
1090template <class _Ptr, class _Alloc>
1091struct __const_void_pointer<_Ptr, _Alloc, false>
1092{
1093#ifndef _LIBCPP_CXX03_LANG
1094    typedef typename pointer_traits<_Ptr>::template rebind<const void> type;
1095#else
1096    typedef typename pointer_traits<_Ptr>::template rebind<const void>::other type;
1097#endif
1098};
1099
1100template <class _Tp>
1101inline _LIBCPP_INLINE_VISIBILITY
1102_Tp*
1103__to_raw_pointer(_Tp* __p) _NOEXCEPT
1104{
1105    return __p;
1106}
1107
1108template <class _Pointer>
1109inline _LIBCPP_INLINE_VISIBILITY
1110typename pointer_traits<_Pointer>::element_type*
1111__to_raw_pointer(_Pointer __p) _NOEXCEPT
1112{
1113    return _VSTD::__to_raw_pointer(__p.operator->());
1114}
1115
1116template <class _Tp>
1117struct __has_size_type
1118{
1119private:
1120    struct __two {char __lx; char __lxx;};
1121    template <class _Up> static __two __test(...);
1122    template <class _Up> static char __test(typename _Up::size_type* = 0);
1123public:
1124    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1125};
1126
1127template <class _Alloc, class _DiffType, bool = __has_size_type<_Alloc>::value>
1128struct __size_type
1129{
1130    typedef typename make_unsigned<_DiffType>::type type;
1131};
1132
1133template <class _Alloc, class _DiffType>
1134struct __size_type<_Alloc, _DiffType, true>
1135{
1136    typedef typename _Alloc::size_type type;
1137};
1138
1139template <class _Tp>
1140struct __has_propagate_on_container_copy_assignment
1141{
1142private:
1143    struct __two {char __lx; char __lxx;};
1144    template <class _Up> static __two __test(...);
1145    template <class _Up> static char __test(typename _Up::propagate_on_container_copy_assignment* = 0);
1146public:
1147    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1148};
1149
1150template <class _Alloc, bool = __has_propagate_on_container_copy_assignment<_Alloc>::value>
1151struct __propagate_on_container_copy_assignment
1152{
1153    typedef false_type type;
1154};
1155
1156template <class _Alloc>
1157struct __propagate_on_container_copy_assignment<_Alloc, true>
1158{
1159    typedef typename _Alloc::propagate_on_container_copy_assignment type;
1160};
1161
1162template <class _Tp>
1163struct __has_propagate_on_container_move_assignment
1164{
1165private:
1166    struct __two {char __lx; char __lxx;};
1167    template <class _Up> static __two __test(...);
1168    template <class _Up> static char __test(typename _Up::propagate_on_container_move_assignment* = 0);
1169public:
1170    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1171};
1172
1173template <class _Alloc, bool = __has_propagate_on_container_move_assignment<_Alloc>::value>
1174struct __propagate_on_container_move_assignment
1175{
1176    typedef false_type type;
1177};
1178
1179template <class _Alloc>
1180struct __propagate_on_container_move_assignment<_Alloc, true>
1181{
1182    typedef typename _Alloc::propagate_on_container_move_assignment type;
1183};
1184
1185template <class _Tp>
1186struct __has_propagate_on_container_swap
1187{
1188private:
1189    struct __two {char __lx; char __lxx;};
1190    template <class _Up> static __two __test(...);
1191    template <class _Up> static char __test(typename _Up::propagate_on_container_swap* = 0);
1192public:
1193    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1194};
1195
1196template <class _Alloc, bool = __has_propagate_on_container_swap<_Alloc>::value>
1197struct __propagate_on_container_swap
1198{
1199    typedef false_type type;
1200};
1201
1202template <class _Alloc>
1203struct __propagate_on_container_swap<_Alloc, true>
1204{
1205    typedef typename _Alloc::propagate_on_container_swap type;
1206};
1207
1208template <class _Tp>
1209struct __has_is_always_equal
1210{
1211private:
1212    struct __two {char __lx; char __lxx;};
1213    template <class _Up> static __two __test(...);
1214    template <class _Up> static char __test(typename _Up::is_always_equal* = 0);
1215public:
1216    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1217};
1218
1219template <class _Alloc, bool = __has_is_always_equal<_Alloc>::value>
1220struct __is_always_equal
1221{
1222    typedef typename _VSTD::is_empty<_Alloc>::type type;
1223};
1224
1225template <class _Alloc>
1226struct __is_always_equal<_Alloc, true>
1227{
1228    typedef typename _Alloc::is_always_equal type;
1229};
1230
1231template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
1232struct __has_rebind_other
1233{
1234private:
1235    struct __two {char __lx; char __lxx;};
1236    template <class _Xp> static __two __test(...);
1237    template <class _Xp> static char __test(typename _Xp::template rebind<_Up>::other* = 0);
1238public:
1239    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1240};
1241
1242template <class _Tp, class _Up>
1243struct __has_rebind_other<_Tp, _Up, false>
1244{
1245    static const bool value = false;
1246};
1247
1248template <class _Tp, class _Up, bool = __has_rebind_other<_Tp, _Up>::value>
1249struct __allocator_traits_rebind
1250{
1251    typedef typename _Tp::template rebind<_Up>::other type;
1252};
1253
1254#ifndef _LIBCPP_HAS_NO_VARIADICS
1255
1256template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up>
1257struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, true>
1258{
1259    typedef typename _Alloc<_Tp, _Args...>::template rebind<_Up>::other type;
1260};
1261
1262template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up>
1263struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, false>
1264{
1265    typedef _Alloc<_Up, _Args...> type;
1266};
1267
1268#else  // _LIBCPP_HAS_NO_VARIADICS
1269
1270template <template <class> class _Alloc, class _Tp, class _Up>
1271struct __allocator_traits_rebind<_Alloc<_Tp>, _Up, true>
1272{
1273    typedef typename _Alloc<_Tp>::template rebind<_Up>::other type;
1274};
1275
1276template <template <class> class _Alloc, class _Tp, class _Up>
1277struct __allocator_traits_rebind<_Alloc<_Tp>, _Up, false>
1278{
1279    typedef _Alloc<_Up> type;
1280};
1281
1282template <template <class, class> class _Alloc, class _Tp, class _A0, class _Up>
1283struct __allocator_traits_rebind<_Alloc<_Tp, _A0>, _Up, true>
1284{
1285    typedef typename _Alloc<_Tp, _A0>::template rebind<_Up>::other type;
1286};
1287
1288template <template <class, class> class _Alloc, class _Tp, class _A0, class _Up>
1289struct __allocator_traits_rebind<_Alloc<_Tp, _A0>, _Up, false>
1290{
1291    typedef _Alloc<_Up, _A0> type;
1292};
1293
1294template <template <class, class, class> class _Alloc, class _Tp, class _A0,
1295                                         class _A1, class _Up>
1296struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1>, _Up, true>
1297{
1298    typedef typename _Alloc<_Tp, _A0, _A1>::template rebind<_Up>::other type;
1299};
1300
1301template <template <class, class, class> class _Alloc, class _Tp, class _A0,
1302                                         class _A1, class _Up>
1303struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1>, _Up, false>
1304{
1305    typedef _Alloc<_Up, _A0, _A1> type;
1306};
1307
1308template <template <class, class, class, class> class _Alloc, class _Tp, class _A0,
1309                                                class _A1, class _A2, class _Up>
1310struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1, _A2>, _Up, true>
1311{
1312    typedef typename _Alloc<_Tp, _A0, _A1, _A2>::template rebind<_Up>::other type;
1313};
1314
1315template <template <class, class, class, class> class _Alloc, class _Tp, class _A0,
1316                                                class _A1, class _A2, class _Up>
1317struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1, _A2>, _Up, false>
1318{
1319    typedef _Alloc<_Up, _A0, _A1, _A2> type;
1320};
1321
1322#endif  // _LIBCPP_HAS_NO_VARIADICS
1323
1324#ifndef _LIBCPP_CXX03_LANG
1325
1326template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1327auto
1328__has_allocate_hint_test(_Alloc&& __a, _SizeType&& __sz, _ConstVoidPtr&& __p)
1329    -> decltype(__a.allocate(__sz, __p), true_type());
1330
1331template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1332auto
1333__has_allocate_hint_test(const _Alloc& __a, _SizeType&& __sz, _ConstVoidPtr&& __p)
1334    -> false_type;
1335
1336template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1337struct __has_allocate_hint
1338    : integral_constant<bool,
1339        is_same<
1340            decltype(__has_allocate_hint_test(declval<_Alloc>(),
1341                                          declval<_SizeType>(),
1342                                          declval<_ConstVoidPtr>())),
1343            true_type>::value>
1344{
1345};
1346
1347#else  // _LIBCPP_CXX03_LANG
1348
1349template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1350struct __has_allocate_hint
1351    : true_type
1352{
1353};
1354
1355#endif  // _LIBCPP_CXX03_LANG
1356
1357#if !defined(_LIBCPP_CXX03_LANG)
1358
1359template <class _Alloc, class _Tp, class ..._Args>
1360decltype(_VSTD::declval<_Alloc>().construct(_VSTD::declval<_Tp*>(),
1361                                           _VSTD::declval<_Args>()...),
1362                                           true_type())
1363__has_construct_test(_Alloc&& __a, _Tp* __p, _Args&& ...__args);
1364
1365template <class _Alloc, class _Pointer, class ..._Args>
1366false_type
1367__has_construct_test(const _Alloc& __a, _Pointer&& __p, _Args&& ...__args);
1368
1369template <class _Alloc, class _Pointer, class ..._Args>
1370struct __has_construct
1371    : integral_constant<bool,
1372        is_same<
1373            decltype(__has_construct_test(declval<_Alloc>(),
1374                                          declval<_Pointer>(),
1375                                          declval<_Args>()...)),
1376            true_type>::value>
1377{
1378};
1379
1380template <class _Alloc, class _Pointer>
1381auto
1382__has_destroy_test(_Alloc&& __a, _Pointer&& __p)
1383    -> decltype(__a.destroy(__p), true_type());
1384
1385template <class _Alloc, class _Pointer>
1386auto
1387__has_destroy_test(const _Alloc& __a, _Pointer&& __p)
1388    -> false_type;
1389
1390template <class _Alloc, class _Pointer>
1391struct __has_destroy
1392    : integral_constant<bool,
1393        is_same<
1394            decltype(__has_destroy_test(declval<_Alloc>(),
1395                                        declval<_Pointer>())),
1396            true_type>::value>
1397{
1398};
1399
1400template <class _Alloc>
1401auto
1402__has_max_size_test(_Alloc&& __a)
1403    -> decltype(__a.max_size(), true_type());
1404
1405template <class _Alloc>
1406auto
1407__has_max_size_test(const volatile _Alloc& __a)
1408    -> false_type;
1409
1410template <class _Alloc>
1411struct __has_max_size
1412    : integral_constant<bool,
1413        is_same<
1414            decltype(__has_max_size_test(declval<_Alloc&>())),
1415            true_type>::value>
1416{
1417};
1418
1419template <class _Alloc>
1420auto
1421__has_select_on_container_copy_construction_test(_Alloc&& __a)
1422    -> decltype(__a.select_on_container_copy_construction(), true_type());
1423
1424template <class _Alloc>
1425auto
1426__has_select_on_container_copy_construction_test(const volatile _Alloc& __a)
1427    -> false_type;
1428
1429template <class _Alloc>
1430struct __has_select_on_container_copy_construction
1431    : integral_constant<bool,
1432        is_same<
1433            decltype(__has_select_on_container_copy_construction_test(declval<_Alloc&>())),
1434            true_type>::value>
1435{
1436};
1437
1438#else  // _LIBCPP_CXX03_LANG
1439
1440#ifndef _LIBCPP_HAS_NO_VARIADICS
1441
1442template <class _Alloc, class _Pointer, class ..._Args>
1443struct __has_construct
1444    : false_type
1445{
1446};
1447
1448#else  // _LIBCPP_HAS_NO_VARIADICS
1449
1450template <class _Alloc, class _Pointer, class _Args>
1451struct __has_construct
1452    : false_type
1453{
1454};
1455
1456#endif  // _LIBCPP_HAS_NO_VARIADICS
1457
1458template <class _Alloc, class _Pointer>
1459struct __has_destroy
1460    : false_type
1461{
1462};
1463
1464template <class _Alloc>
1465struct __has_max_size
1466    : true_type
1467{
1468};
1469
1470template <class _Alloc>
1471struct __has_select_on_container_copy_construction
1472    : false_type
1473{
1474};
1475
1476#endif  // _LIBCPP_CXX03_LANG
1477
1478template <class _Alloc, class _Ptr, bool = __has_difference_type<_Alloc>::value>
1479struct __alloc_traits_difference_type
1480{
1481    typedef typename pointer_traits<_Ptr>::difference_type type;
1482};
1483
1484template <class _Alloc, class _Ptr>
1485struct __alloc_traits_difference_type<_Alloc, _Ptr, true>
1486{
1487    typedef typename _Alloc::difference_type type;
1488};
1489
1490template <class _Alloc>
1491struct _LIBCPP_TEMPLATE_VIS allocator_traits
1492{
1493    typedef _Alloc                              allocator_type;
1494    typedef typename allocator_type::value_type value_type;
1495
1496    typedef typename __pointer_type<value_type, allocator_type>::type pointer;
1497    typedef typename __const_pointer<value_type, pointer, allocator_type>::type const_pointer;
1498    typedef typename __void_pointer<pointer, allocator_type>::type void_pointer;
1499    typedef typename __const_void_pointer<pointer, allocator_type>::type const_void_pointer;
1500
1501    typedef typename __alloc_traits_difference_type<allocator_type, pointer>::type difference_type;
1502    typedef typename __size_type<allocator_type, difference_type>::type size_type;
1503
1504    typedef typename __propagate_on_container_copy_assignment<allocator_type>::type
1505                     propagate_on_container_copy_assignment;
1506    typedef typename __propagate_on_container_move_assignment<allocator_type>::type
1507                     propagate_on_container_move_assignment;
1508    typedef typename __propagate_on_container_swap<allocator_type>::type
1509                     propagate_on_container_swap;
1510    typedef typename __is_always_equal<allocator_type>::type
1511                     is_always_equal;
1512
1513#ifndef _LIBCPP_CXX03_LANG
1514    template <class _Tp> using rebind_alloc =
1515                  typename __allocator_traits_rebind<allocator_type, _Tp>::type;
1516    template <class _Tp> using rebind_traits = allocator_traits<rebind_alloc<_Tp>>;
1517#else  // _LIBCPP_CXX03_LANG
1518    template <class _Tp> struct rebind_alloc
1519        {typedef typename __allocator_traits_rebind<allocator_type, _Tp>::type other;};
1520    template <class _Tp> struct rebind_traits
1521        {typedef allocator_traits<typename rebind_alloc<_Tp>::other> other;};
1522#endif  // _LIBCPP_CXX03_LANG
1523
1524    _LIBCPP_INLINE_VISIBILITY
1525    static pointer allocate(allocator_type& __a, size_type __n)
1526        {return __a.allocate(__n);}
1527    _LIBCPP_INLINE_VISIBILITY
1528    static pointer allocate(allocator_type& __a, size_type __n, const_void_pointer __hint)
1529        {return allocate(__a, __n, __hint,
1530            __has_allocate_hint<allocator_type, size_type, const_void_pointer>());}
1531
1532    _LIBCPP_INLINE_VISIBILITY
1533    static void deallocate(allocator_type& __a, pointer __p, size_type __n) _NOEXCEPT
1534        {__a.deallocate(__p, __n);}
1535
1536#ifndef _LIBCPP_HAS_NO_VARIADICS
1537    template <class _Tp, class... _Args>
1538        _LIBCPP_INLINE_VISIBILITY
1539        static void construct(allocator_type& __a, _Tp* __p, _Args&&... __args)
1540            {__construct(__has_construct<allocator_type, _Tp*, _Args...>(),
1541                         __a, __p, _VSTD::forward<_Args>(__args)...);}
1542#else  // _LIBCPP_HAS_NO_VARIADICS
1543    template <class _Tp>
1544        _LIBCPP_INLINE_VISIBILITY
1545        static void construct(allocator_type&, _Tp* __p)
1546            {
1547                ::new ((void*)__p) _Tp();
1548            }
1549    template <class _Tp, class _A0>
1550        _LIBCPP_INLINE_VISIBILITY
1551        static void construct(allocator_type&, _Tp* __p, const _A0& __a0)
1552            {
1553                ::new ((void*)__p) _Tp(__a0);
1554            }
1555    template <class _Tp, class _A0, class _A1>
1556        _LIBCPP_INLINE_VISIBILITY
1557        static void construct(allocator_type&, _Tp* __p, const _A0& __a0,
1558                              const _A1& __a1)
1559            {
1560                ::new ((void*)__p) _Tp(__a0, __a1);
1561            }
1562    template <class _Tp, class _A0, class _A1, class _A2>
1563        _LIBCPP_INLINE_VISIBILITY
1564        static void construct(allocator_type&, _Tp* __p, const _A0& __a0,
1565                              const _A1& __a1, const _A2& __a2)
1566            {
1567                ::new ((void*)__p) _Tp(__a0, __a1, __a2);
1568            }
1569#endif  // _LIBCPP_HAS_NO_VARIADICS
1570
1571    template <class _Tp>
1572        _LIBCPP_INLINE_VISIBILITY
1573        static void destroy(allocator_type& __a, _Tp* __p)
1574            {__destroy(__has_destroy<allocator_type, _Tp*>(), __a, __p);}
1575
1576    _LIBCPP_INLINE_VISIBILITY
1577    static size_type max_size(const allocator_type& __a) _NOEXCEPT
1578        {return __max_size(__has_max_size<const allocator_type>(), __a);}
1579
1580    _LIBCPP_INLINE_VISIBILITY
1581    static allocator_type
1582        select_on_container_copy_construction(const allocator_type& __a)
1583            {return select_on_container_copy_construction(
1584                __has_select_on_container_copy_construction<const allocator_type>(),
1585                __a);}
1586
1587    template <class _Ptr>
1588        _LIBCPP_INLINE_VISIBILITY
1589        static
1590        void
1591        __construct_forward(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __begin2)
1592        {
1593            for (; __begin1 != __end1; ++__begin1, ++__begin2)
1594                construct(__a, _VSTD::__to_raw_pointer(__begin2), _VSTD::move_if_noexcept(*__begin1));
1595        }
1596
1597    template <class _Tp>
1598        _LIBCPP_INLINE_VISIBILITY
1599        static
1600        typename enable_if
1601        <
1602            (is_same<allocator_type, allocator<_Tp> >::value
1603                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1604             is_trivially_move_constructible<_Tp>::value,
1605            void
1606        >::type
1607        __construct_forward(allocator_type&, _Tp* __begin1, _Tp* __end1, _Tp*& __begin2)
1608        {
1609            ptrdiff_t _Np = __end1 - __begin1;
1610            if (_Np > 0)
1611            {
1612                _VSTD::memcpy(__begin2, __begin1, _Np * sizeof(_Tp));
1613                __begin2 += _Np;
1614            }
1615        }
1616
1617    template <class _Iter, class _Ptr>
1618        _LIBCPP_INLINE_VISIBILITY
1619        static
1620        void
1621        __construct_range_forward(allocator_type& __a, _Iter __begin1, _Iter __end1, _Ptr& __begin2)
1622        {
1623            for (; __begin1 != __end1; ++__begin1, (void) ++__begin2)
1624                construct(__a, _VSTD::__to_raw_pointer(__begin2), *__begin1);
1625        }
1626
1627    template <class _Tp>
1628        _LIBCPP_INLINE_VISIBILITY
1629        static
1630        typename enable_if
1631        <
1632            (is_same<allocator_type, allocator<_Tp> >::value
1633                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1634             is_trivially_move_constructible<_Tp>::value,
1635            void
1636        >::type
1637        __construct_range_forward(allocator_type&, _Tp* __begin1, _Tp* __end1, _Tp*& __begin2)
1638        {
1639            typedef typename remove_const<_Tp>::type _Vp;
1640            ptrdiff_t _Np = __end1 - __begin1;
1641            if (_Np > 0)
1642            {
1643                _VSTD::memcpy(const_cast<_Vp*>(__begin2), __begin1, _Np * sizeof(_Tp));
1644                __begin2 += _Np;
1645            }
1646        }
1647
1648    template <class _Ptr>
1649        _LIBCPP_INLINE_VISIBILITY
1650        static
1651        void
1652        __construct_backward(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __end2)
1653        {
1654            while (__end1 != __begin1)
1655            {
1656                construct(__a, _VSTD::__to_raw_pointer(__end2-1), _VSTD::move_if_noexcept(*--__end1));
1657                --__end2;
1658            }
1659        }
1660
1661    template <class _Tp>
1662        _LIBCPP_INLINE_VISIBILITY
1663        static
1664        typename enable_if
1665        <
1666            (is_same<allocator_type, allocator<_Tp> >::value
1667                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1668             is_trivially_move_constructible<_Tp>::value,
1669            void
1670        >::type
1671        __construct_backward(allocator_type&, _Tp* __begin1, _Tp* __end1, _Tp*& __end2)
1672        {
1673            ptrdiff_t _Np = __end1 - __begin1;
1674            __end2 -= _Np;
1675            if (_Np > 0)
1676                _VSTD::memcpy(__end2, __begin1, _Np * sizeof(_Tp));
1677        }
1678
1679private:
1680
1681    _LIBCPP_INLINE_VISIBILITY
1682    static pointer allocate(allocator_type& __a, size_type __n,
1683        const_void_pointer __hint, true_type)
1684        {return __a.allocate(__n, __hint);}
1685    _LIBCPP_INLINE_VISIBILITY
1686    static pointer allocate(allocator_type& __a, size_type __n,
1687        const_void_pointer, false_type)
1688        {return __a.allocate(__n);}
1689
1690#ifndef _LIBCPP_HAS_NO_VARIADICS
1691    template <class _Tp, class... _Args>
1692        _LIBCPP_INLINE_VISIBILITY
1693        static void __construct(true_type, allocator_type& __a, _Tp* __p, _Args&&... __args)
1694            {__a.construct(__p, _VSTD::forward<_Args>(__args)...);}
1695    template <class _Tp, class... _Args>
1696        _LIBCPP_INLINE_VISIBILITY
1697        static void __construct(false_type, allocator_type&, _Tp* __p, _Args&&... __args)
1698            {
1699                ::new ((void*)__p) _Tp(_VSTD::forward<_Args>(__args)...);
1700            }
1701#endif  // _LIBCPP_HAS_NO_VARIADICS
1702
1703    template <class _Tp>
1704        _LIBCPP_INLINE_VISIBILITY
1705        static void __destroy(true_type, allocator_type& __a, _Tp* __p)
1706            {__a.destroy(__p);}
1707    template <class _Tp>
1708        _LIBCPP_INLINE_VISIBILITY
1709        static void __destroy(false_type, allocator_type&, _Tp* __p)
1710            {
1711                __p->~_Tp();
1712            }
1713
1714    _LIBCPP_INLINE_VISIBILITY
1715    static size_type __max_size(true_type, const allocator_type& __a)
1716            {return __a.max_size();}
1717    _LIBCPP_INLINE_VISIBILITY
1718    static size_type __max_size(false_type, const allocator_type&)
1719            {return numeric_limits<size_type>::max() / sizeof(value_type);}
1720
1721    _LIBCPP_INLINE_VISIBILITY
1722    static allocator_type
1723        select_on_container_copy_construction(true_type, const allocator_type& __a)
1724            {return __a.select_on_container_copy_construction();}
1725    _LIBCPP_INLINE_VISIBILITY
1726    static allocator_type
1727        select_on_container_copy_construction(false_type, const allocator_type& __a)
1728            {return __a;}
1729};
1730
1731template <class _Traits, class _Tp>
1732struct __rebind_alloc_helper
1733{
1734#ifndef _LIBCPP_CXX03_LANG
1735    typedef typename _Traits::template rebind_alloc<_Tp>        type;
1736#else
1737    typedef typename _Traits::template rebind_alloc<_Tp>::other type;
1738#endif
1739};
1740
1741// allocator
1742
1743template <class _Tp>
1744class _LIBCPP_TEMPLATE_VIS allocator
1745{
1746public:
1747    typedef size_t            size_type;
1748    typedef ptrdiff_t         difference_type;
1749    typedef _Tp*              pointer;
1750    typedef const _Tp*        const_pointer;
1751    typedef _Tp&              reference;
1752    typedef const _Tp&        const_reference;
1753    typedef _Tp               value_type;
1754
1755    typedef true_type propagate_on_container_move_assignment;
1756    typedef true_type is_always_equal;
1757
1758    template <class _Up> struct rebind {typedef allocator<_Up> other;};
1759
1760    _LIBCPP_INLINE_VISIBILITY allocator() _NOEXCEPT {}
1761    template <class _Up> _LIBCPP_INLINE_VISIBILITY allocator(const allocator<_Up>&) _NOEXCEPT {}
1762    _LIBCPP_INLINE_VISIBILITY pointer address(reference __x) const _NOEXCEPT
1763        {return _VSTD::addressof(__x);}
1764    _LIBCPP_INLINE_VISIBILITY const_pointer address(const_reference __x) const _NOEXCEPT
1765        {return _VSTD::addressof(__x);}
1766    _LIBCPP_INLINE_VISIBILITY pointer allocate(size_type __n, allocator<void>::const_pointer = 0)
1767        {
1768        if (__n > max_size())
1769            __throw_length_error("allocator<T>::allocate(size_t n)"
1770                                 " 'n' exceeds maximum supported size");
1771        return static_cast<pointer>(_VSTD::__allocate(__n * sizeof(_Tp)));
1772        }
1773    _LIBCPP_INLINE_VISIBILITY void deallocate(pointer __p, size_type) _NOEXCEPT
1774        {_VSTD::__libcpp_deallocate((void*)__p);}
1775    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT
1776        {return size_type(~0) / sizeof(_Tp);}
1777#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1778    template <class _Up, class... _Args>
1779        _LIBCPP_INLINE_VISIBILITY
1780        void
1781        construct(_Up* __p, _Args&&... __args)
1782        {
1783            ::new((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
1784        }
1785#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1786        _LIBCPP_INLINE_VISIBILITY
1787        void
1788        construct(pointer __p)
1789        {
1790            ::new((void*)__p) _Tp();
1791        }
1792# if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1793
1794    template <class _A0>
1795        _LIBCPP_INLINE_VISIBILITY
1796        void
1797        construct(pointer __p, _A0& __a0)
1798        {
1799            ::new((void*)__p) _Tp(__a0);
1800        }
1801    template <class _A0>
1802        _LIBCPP_INLINE_VISIBILITY
1803        void
1804        construct(pointer __p, const _A0& __a0)
1805        {
1806            ::new((void*)__p) _Tp(__a0);
1807        }
1808# endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1809    template <class _A0, class _A1>
1810        _LIBCPP_INLINE_VISIBILITY
1811        void
1812        construct(pointer __p, _A0& __a0, _A1& __a1)
1813        {
1814            ::new((void*)__p) _Tp(__a0, __a1);
1815        }
1816    template <class _A0, class _A1>
1817        _LIBCPP_INLINE_VISIBILITY
1818        void
1819        construct(pointer __p, const _A0& __a0, _A1& __a1)
1820        {
1821            ::new((void*)__p) _Tp(__a0, __a1);
1822        }
1823    template <class _A0, class _A1>
1824        _LIBCPP_INLINE_VISIBILITY
1825        void
1826        construct(pointer __p, _A0& __a0, const _A1& __a1)
1827        {
1828            ::new((void*)__p) _Tp(__a0, __a1);
1829        }
1830    template <class _A0, class _A1>
1831        _LIBCPP_INLINE_VISIBILITY
1832        void
1833        construct(pointer __p, const _A0& __a0, const _A1& __a1)
1834        {
1835            ::new((void*)__p) _Tp(__a0, __a1);
1836        }
1837#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1838    _LIBCPP_INLINE_VISIBILITY void destroy(pointer __p) {__p->~_Tp();}
1839};
1840
1841template <class _Tp>
1842class _LIBCPP_TEMPLATE_VIS allocator<const _Tp>
1843{
1844public:
1845    typedef size_t            size_type;
1846    typedef ptrdiff_t         difference_type;
1847    typedef const _Tp*        pointer;
1848    typedef const _Tp*        const_pointer;
1849    typedef const _Tp&        reference;
1850    typedef const _Tp&        const_reference;
1851    typedef const _Tp         value_type;
1852
1853    typedef true_type propagate_on_container_move_assignment;
1854    typedef true_type is_always_equal;
1855
1856    template <class _Up> struct rebind {typedef allocator<_Up> other;};
1857
1858    _LIBCPP_INLINE_VISIBILITY allocator() _NOEXCEPT {}
1859    template <class _Up> _LIBCPP_INLINE_VISIBILITY allocator(const allocator<_Up>&) _NOEXCEPT {}
1860    _LIBCPP_INLINE_VISIBILITY const_pointer address(const_reference __x) const _NOEXCEPT
1861        {return _VSTD::addressof(__x);}
1862    _LIBCPP_INLINE_VISIBILITY pointer allocate(size_type __n, allocator<void>::const_pointer = 0)
1863    {
1864        if (__n > max_size())
1865            __throw_length_error("allocator<const T>::allocate(size_t n)"
1866                                 " 'n' exceeds maximum supported size");
1867        return static_cast<pointer>(_VSTD::__allocate(__n * sizeof(_Tp)));
1868    }
1869    _LIBCPP_INLINE_VISIBILITY void deallocate(pointer __p, size_type) _NOEXCEPT
1870        {_VSTD::__libcpp_deallocate((void*)__p);}
1871    _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT
1872        {return size_type(~0) / sizeof(_Tp);}
1873#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1874    template <class _Up, class... _Args>
1875        _LIBCPP_INLINE_VISIBILITY
1876        void
1877        construct(_Up* __p, _Args&&... __args)
1878        {
1879            ::new((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
1880        }
1881#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1882        _LIBCPP_INLINE_VISIBILITY
1883        void
1884        construct(pointer __p)
1885        {
1886            ::new((void*)__p) _Tp();
1887        }
1888# if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1889
1890    template <class _A0>
1891        _LIBCPP_INLINE_VISIBILITY
1892        void
1893        construct(pointer __p, _A0& __a0)
1894        {
1895            ::new((void*)__p) _Tp(__a0);
1896        }
1897    template <class _A0>
1898        _LIBCPP_INLINE_VISIBILITY
1899        void
1900        construct(pointer __p, const _A0& __a0)
1901        {
1902            ::new((void*)__p) _Tp(__a0);
1903        }
1904# endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1905    template <class _A0, class _A1>
1906        _LIBCPP_INLINE_VISIBILITY
1907        void
1908        construct(pointer __p, _A0& __a0, _A1& __a1)
1909        {
1910            ::new((void*)__p) _Tp(__a0, __a1);
1911        }
1912    template <class _A0, class _A1>
1913        _LIBCPP_INLINE_VISIBILITY
1914        void
1915        construct(pointer __p, const _A0& __a0, _A1& __a1)
1916        {
1917            ::new((void*)__p) _Tp(__a0, __a1);
1918        }
1919    template <class _A0, class _A1>
1920        _LIBCPP_INLINE_VISIBILITY
1921        void
1922        construct(pointer __p, _A0& __a0, const _A1& __a1)
1923        {
1924            ::new((void*)__p) _Tp(__a0, __a1);
1925        }
1926    template <class _A0, class _A1>
1927        _LIBCPP_INLINE_VISIBILITY
1928        void
1929        construct(pointer __p, const _A0& __a0, const _A1& __a1)
1930        {
1931            ::new((void*)__p) _Tp(__a0, __a1);
1932        }
1933#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1934    _LIBCPP_INLINE_VISIBILITY void destroy(pointer __p) {__p->~_Tp();}
1935};
1936
1937template <class _Tp, class _Up>
1938inline _LIBCPP_INLINE_VISIBILITY
1939bool operator==(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return true;}
1940
1941template <class _Tp, class _Up>
1942inline _LIBCPP_INLINE_VISIBILITY
1943bool operator!=(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return false;}
1944
1945template <class _OutputIterator, class _Tp>
1946class _LIBCPP_TEMPLATE_VIS raw_storage_iterator
1947    : public iterator<output_iterator_tag,
1948                      _Tp,                                         // purposefully not C++03
1949                      ptrdiff_t,                                   // purposefully not C++03
1950                      _Tp*,                                        // purposefully not C++03
1951                      raw_storage_iterator<_OutputIterator, _Tp>&> // purposefully not C++03
1952{
1953private:
1954    _OutputIterator __x_;
1955public:
1956    _LIBCPP_INLINE_VISIBILITY explicit raw_storage_iterator(_OutputIterator __x) : __x_(__x) {}
1957    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator*() {return *this;}
1958    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(const _Tp& __element)
1959        {::new(&*__x_) _Tp(__element); return *this;}
1960#if _LIBCPP_STD_VER >= 14
1961    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(_Tp&& __element)
1962        {::new(&*__x_) _Tp(_VSTD::move(__element)); return *this;}
1963#endif
1964    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator++() {++__x_; return *this;}
1965    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator  operator++(int)
1966        {raw_storage_iterator __t(*this); ++__x_; return __t;}
1967#if _LIBCPP_STD_VER >= 14
1968    _LIBCPP_INLINE_VISIBILITY _OutputIterator base() const { return __x_; }
1969#endif
1970};
1971
1972template <class _Tp>
1973pair<_Tp*, ptrdiff_t>
1974get_temporary_buffer(ptrdiff_t __n) _NOEXCEPT
1975{
1976    pair<_Tp*, ptrdiff_t> __r(0, 0);
1977    const ptrdiff_t __m = (~ptrdiff_t(0) ^
1978                           ptrdiff_t(ptrdiff_t(1) << (sizeof(ptrdiff_t) * __CHAR_BIT__ - 1)))
1979                           / sizeof(_Tp);
1980    if (__n > __m)
1981        __n = __m;
1982    while (__n > 0)
1983    {
1984        __r.first = static_cast<_Tp*>(::operator new(__n * sizeof(_Tp), nothrow));
1985        if (__r.first)
1986        {
1987            __r.second = __n;
1988            break;
1989        }
1990        __n /= 2;
1991    }
1992    return __r;
1993}
1994
1995template <class _Tp>
1996inline _LIBCPP_INLINE_VISIBILITY
1997void return_temporary_buffer(_Tp* __p) _NOEXCEPT {::operator delete(__p);}
1998
1999#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
2000template <class _Tp>
2001struct auto_ptr_ref
2002{
2003    _Tp* __ptr_;
2004};
2005
2006template<class _Tp>
2007class _LIBCPP_TEMPLATE_VIS auto_ptr
2008{
2009private:
2010    _Tp* __ptr_;
2011public:
2012    typedef _Tp element_type;
2013
2014    _LIBCPP_INLINE_VISIBILITY explicit auto_ptr(_Tp* __p = 0) throw() : __ptr_(__p) {}
2015    _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr& __p) throw() : __ptr_(__p.release()) {}
2016    template<class _Up> _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr<_Up>& __p) throw()
2017        : __ptr_(__p.release()) {}
2018    _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr& __p) throw()
2019        {reset(__p.release()); return *this;}
2020    template<class _Up> _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr<_Up>& __p) throw()
2021        {reset(__p.release()); return *this;}
2022    _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr_ref<_Tp> __p) throw()
2023        {reset(__p.__ptr_); return *this;}
2024    _LIBCPP_INLINE_VISIBILITY ~auto_ptr() throw() {delete __ptr_;}
2025
2026    _LIBCPP_INLINE_VISIBILITY _Tp& operator*() const throw()
2027        {return *__ptr_;}
2028    _LIBCPP_INLINE_VISIBILITY _Tp* operator->() const throw() {return __ptr_;}
2029    _LIBCPP_INLINE_VISIBILITY _Tp* get() const throw() {return __ptr_;}
2030    _LIBCPP_INLINE_VISIBILITY _Tp* release() throw()
2031    {
2032        _Tp* __t = __ptr_;
2033        __ptr_ = 0;
2034        return __t;
2035    }
2036    _LIBCPP_INLINE_VISIBILITY void reset(_Tp* __p = 0) throw()
2037    {
2038        if (__ptr_ != __p)
2039            delete __ptr_;
2040        __ptr_ = __p;
2041    }
2042
2043    _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr_ref<_Tp> __p) throw() : __ptr_(__p.__ptr_) {}
2044    template<class _Up> _LIBCPP_INLINE_VISIBILITY operator auto_ptr_ref<_Up>() throw()
2045        {auto_ptr_ref<_Up> __t; __t.__ptr_ = release(); return __t;}
2046    template<class _Up> _LIBCPP_INLINE_VISIBILITY operator auto_ptr<_Up>() throw()
2047        {return auto_ptr<_Up>(release());}
2048};
2049
2050template <>
2051class _LIBCPP_TEMPLATE_VIS auto_ptr<void>
2052{
2053public:
2054    typedef void element_type;
2055};
2056#endif
2057
2058template <class _T1, class _T2, bool = is_same<typename remove_cv<_T1>::type,
2059                                                     typename remove_cv<_T2>::type>::value,
2060                                bool = is_empty<_T1>::value
2061                                       && !__libcpp_is_final<_T1>::value,
2062                                bool = is_empty<_T2>::value
2063                                       && !__libcpp_is_final<_T2>::value
2064         >
2065struct __libcpp_compressed_pair_switch;
2066
2067template <class _T1, class _T2, bool IsSame>
2068struct __libcpp_compressed_pair_switch<_T1, _T2, IsSame, false, false> {enum {value = 0};};
2069
2070template <class _T1, class _T2, bool IsSame>
2071struct __libcpp_compressed_pair_switch<_T1, _T2, IsSame, true, false>  {enum {value = 1};};
2072
2073template <class _T1, class _T2, bool IsSame>
2074struct __libcpp_compressed_pair_switch<_T1, _T2, IsSame, false, true>  {enum {value = 2};};
2075
2076template <class _T1, class _T2>
2077struct __libcpp_compressed_pair_switch<_T1, _T2, false, true, true>    {enum {value = 3};};
2078
2079template <class _T1, class _T2>
2080struct __libcpp_compressed_pair_switch<_T1, _T2, true, true, true>     {enum {value = 1};};
2081
2082template <class _T1, class _T2, unsigned = __libcpp_compressed_pair_switch<_T1, _T2>::value>
2083class __libcpp_compressed_pair_imp;
2084
2085template <class _T1, class _T2>
2086class __libcpp_compressed_pair_imp<_T1, _T2, 0>
2087{
2088private:
2089    _T1 __first_;
2090    _T2 __second_;
2091public:
2092    typedef _T1 _T1_param;
2093    typedef _T2 _T2_param;
2094
2095    typedef typename remove_reference<_T1>::type& _T1_reference;
2096    typedef typename remove_reference<_T2>::type& _T2_reference;
2097
2098    typedef const typename remove_reference<_T1>::type& _T1_const_reference;
2099    typedef const typename remove_reference<_T2>::type& _T2_const_reference;
2100
2101    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() : __first_(), __second_() {}
2102    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2103        : __first_(_VSTD::forward<_T1_param>(__t1)), __second_() {}
2104    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2105        : __first_(), __second_(_VSTD::forward<_T2_param>(__t2)) {}
2106    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2107        : __first_(_VSTD::forward<_T1_param>(__t1)), __second_(_VSTD::forward<_T2_param>(__t2)) {}
2108
2109#ifndef _LIBCPP_HAS_NO_VARIADICS
2110
2111    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2112        _LIBCPP_INLINE_VISIBILITY
2113        __libcpp_compressed_pair_imp(piecewise_construct_t,
2114                                     tuple<_Args1...> __first_args,
2115                                     tuple<_Args2...> __second_args,
2116                                     __tuple_indices<_I1...>,
2117                                     __tuple_indices<_I2...>)
2118            : __first_(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...),
2119              __second_(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...)
2120            {}
2121
2122#endif  // _LIBCPP_HAS_NO_VARIADICS
2123
2124    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return __first_;}
2125    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return __first_;}
2126
2127    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return __second_;}
2128    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return __second_;}
2129
2130    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp& __x)
2131        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2132                   __is_nothrow_swappable<_T2>::value)
2133    {
2134        using _VSTD::swap;
2135        swap(__first_, __x.__first_);
2136        swap(__second_, __x.__second_);
2137    }
2138};
2139
2140template <class _T1, class _T2>
2141class __libcpp_compressed_pair_imp<_T1, _T2, 1>
2142    : private _T1
2143{
2144private:
2145    _T2 __second_;
2146public:
2147    typedef _T1 _T1_param;
2148    typedef _T2 _T2_param;
2149
2150    typedef _T1&                                        _T1_reference;
2151    typedef typename remove_reference<_T2>::type& _T2_reference;
2152
2153    typedef const _T1&                                        _T1_const_reference;
2154    typedef const typename remove_reference<_T2>::type& _T2_const_reference;
2155
2156    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() : __second_() {}
2157    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2158        : _T1(_VSTD::forward<_T1_param>(__t1)), __second_() {}
2159    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2160        : __second_(_VSTD::forward<_T2_param>(__t2)) {}
2161    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2162        : _T1(_VSTD::forward<_T1_param>(__t1)), __second_(_VSTD::forward<_T2_param>(__t2)) {}
2163
2164#ifndef _LIBCPP_HAS_NO_VARIADICS
2165
2166    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2167        _LIBCPP_INLINE_VISIBILITY
2168        __libcpp_compressed_pair_imp(piecewise_construct_t,
2169                                     tuple<_Args1...> __first_args,
2170                                     tuple<_Args2...> __second_args,
2171                                     __tuple_indices<_I1...>,
2172                                     __tuple_indices<_I2...>)
2173            : _T1(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...),
2174              __second_(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...)
2175            {}
2176
2177#endif  // _LIBCPP_HAS_NO_VARIADICS
2178
2179    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return *this;}
2180    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return *this;}
2181
2182    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return __second_;}
2183    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return __second_;}
2184
2185    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp& __x)
2186        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2187                   __is_nothrow_swappable<_T2>::value)
2188    {
2189        using _VSTD::swap;
2190        swap(__second_, __x.__second_);
2191    }
2192};
2193
2194template <class _T1, class _T2>
2195class __libcpp_compressed_pair_imp<_T1, _T2, 2>
2196    : private _T2
2197{
2198private:
2199    _T1 __first_;
2200public:
2201    typedef _T1 _T1_param;
2202    typedef _T2 _T2_param;
2203
2204    typedef typename remove_reference<_T1>::type& _T1_reference;
2205    typedef _T2&                                        _T2_reference;
2206
2207    typedef const typename remove_reference<_T1>::type& _T1_const_reference;
2208    typedef const _T2&                                        _T2_const_reference;
2209
2210    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() : __first_() {}
2211    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2212        : __first_(_VSTD::forward<_T1_param>(__t1)) {}
2213    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2214        : _T2(_VSTD::forward<_T2_param>(__t2)), __first_() {}
2215    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2216        _NOEXCEPT_(is_nothrow_move_constructible<_T1>::value &&
2217                   is_nothrow_move_constructible<_T2>::value)
2218        : _T2(_VSTD::forward<_T2_param>(__t2)), __first_(_VSTD::forward<_T1_param>(__t1)) {}
2219
2220#ifndef _LIBCPP_HAS_NO_VARIADICS
2221
2222    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2223        _LIBCPP_INLINE_VISIBILITY
2224        __libcpp_compressed_pair_imp(piecewise_construct_t,
2225                                     tuple<_Args1...> __first_args,
2226                                     tuple<_Args2...> __second_args,
2227                                     __tuple_indices<_I1...>,
2228                                     __tuple_indices<_I2...>)
2229            : _T2(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...),
2230              __first_(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...)
2231
2232            {}
2233
2234#endif  // _LIBCPP_HAS_NO_VARIADICS
2235
2236    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return __first_;}
2237    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return __first_;}
2238
2239    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return *this;}
2240    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return *this;}
2241
2242    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp& __x)
2243        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2244                   __is_nothrow_swappable<_T2>::value)
2245    {
2246        using _VSTD::swap;
2247        swap(__first_, __x.__first_);
2248    }
2249};
2250
2251template <class _T1, class _T2>
2252class __libcpp_compressed_pair_imp<_T1, _T2, 3>
2253    : private _T1,
2254      private _T2
2255{
2256public:
2257    typedef _T1 _T1_param;
2258    typedef _T2 _T2_param;
2259
2260    typedef _T1& _T1_reference;
2261    typedef _T2& _T2_reference;
2262
2263    typedef const _T1& _T1_const_reference;
2264    typedef const _T2& _T2_const_reference;
2265
2266    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp() {}
2267    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T1_param __t1)
2268        : _T1(_VSTD::forward<_T1_param>(__t1)) {}
2269    _LIBCPP_INLINE_VISIBILITY explicit __libcpp_compressed_pair_imp(_T2_param __t2)
2270        : _T2(_VSTD::forward<_T2_param>(__t2)) {}
2271    _LIBCPP_INLINE_VISIBILITY __libcpp_compressed_pair_imp(_T1_param __t1, _T2_param __t2)
2272        : _T1(_VSTD::forward<_T1_param>(__t1)), _T2(_VSTD::forward<_T2_param>(__t2)) {}
2273
2274#ifndef _LIBCPP_HAS_NO_VARIADICS
2275
2276    template <class... _Args1, class... _Args2, size_t... _I1, size_t... _I2>
2277        _LIBCPP_INLINE_VISIBILITY
2278        __libcpp_compressed_pair_imp(piecewise_construct_t,
2279                                     tuple<_Args1...> __first_args,
2280                                     tuple<_Args2...> __second_args,
2281                                     __tuple_indices<_I1...>,
2282                                     __tuple_indices<_I2...>)
2283            : _T1(_VSTD::forward<_Args1>(_VSTD::get<_I1>(__first_args))...),
2284              _T2(_VSTD::forward<_Args2>(_VSTD::get<_I2>(__second_args))...)
2285            {}
2286
2287#endif  // _LIBCPP_HAS_NO_VARIADICS
2288
2289    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return *this;}
2290    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return *this;}
2291
2292    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return *this;}
2293    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return *this;}
2294
2295    _LIBCPP_INLINE_VISIBILITY void swap(__libcpp_compressed_pair_imp&)
2296        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2297                   __is_nothrow_swappable<_T2>::value)
2298    {
2299    }
2300};
2301
2302template <class _T1, class _T2>
2303class __compressed_pair
2304    : private __libcpp_compressed_pair_imp<_T1, _T2>
2305{
2306    typedef __libcpp_compressed_pair_imp<_T1, _T2> base;
2307public:
2308    typedef typename base::_T1_param _T1_param;
2309    typedef typename base::_T2_param _T2_param;
2310
2311    typedef typename base::_T1_reference _T1_reference;
2312    typedef typename base::_T2_reference _T2_reference;
2313
2314    typedef typename base::_T1_const_reference _T1_const_reference;
2315    typedef typename base::_T2_const_reference _T2_const_reference;
2316
2317    _LIBCPP_INLINE_VISIBILITY __compressed_pair() {}
2318    _LIBCPP_INLINE_VISIBILITY explicit __compressed_pair(_T1_param __t1)
2319        : base(_VSTD::forward<_T1_param>(__t1)) {}
2320    _LIBCPP_INLINE_VISIBILITY explicit __compressed_pair(_T2_param __t2)
2321        : base(_VSTD::forward<_T2_param>(__t2)) {}
2322    _LIBCPP_INLINE_VISIBILITY __compressed_pair(_T1_param __t1, _T2_param __t2)
2323        : base(_VSTD::forward<_T1_param>(__t1), _VSTD::forward<_T2_param>(__t2)) {}
2324
2325#ifndef _LIBCPP_HAS_NO_VARIADICS
2326
2327    template <class... _Args1, class... _Args2>
2328        _LIBCPP_INLINE_VISIBILITY
2329        __compressed_pair(piecewise_construct_t __pc, tuple<_Args1...> __first_args,
2330                                                      tuple<_Args2...> __second_args)
2331            : base(__pc, _VSTD::move(__first_args), _VSTD::move(__second_args),
2332                   typename __make_tuple_indices<sizeof...(_Args1)>::type(),
2333                   typename __make_tuple_indices<sizeof...(_Args2) >::type())
2334            {}
2335
2336#endif  // _LIBCPP_HAS_NO_VARIADICS
2337
2338    _LIBCPP_INLINE_VISIBILITY _T1_reference       first() _NOEXCEPT       {return base::first();}
2339    _LIBCPP_INLINE_VISIBILITY _T1_const_reference first() const _NOEXCEPT {return base::first();}
2340
2341    _LIBCPP_INLINE_VISIBILITY _T2_reference       second() _NOEXCEPT       {return base::second();}
2342    _LIBCPP_INLINE_VISIBILITY _T2_const_reference second() const _NOEXCEPT {return base::second();}
2343
2344    _LIBCPP_INLINE_VISIBILITY void swap(__compressed_pair& __x)
2345        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2346                   __is_nothrow_swappable<_T2>::value)
2347        {base::swap(__x);}
2348};
2349
2350template <class _T1, class _T2>
2351inline _LIBCPP_INLINE_VISIBILITY
2352void
2353swap(__compressed_pair<_T1, _T2>& __x, __compressed_pair<_T1, _T2>& __y)
2354        _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2355                   __is_nothrow_swappable<_T2>::value)
2356    {__x.swap(__y);}
2357
2358// __same_or_less_cv_qualified
2359
2360template <class _Ptr1, class _Ptr2,
2361          bool = is_same<typename remove_cv<typename pointer_traits<_Ptr1>::element_type>::type,
2362                         typename remove_cv<typename pointer_traits<_Ptr2>::element_type>::type
2363                        >::value
2364         >
2365struct __same_or_less_cv_qualified_imp
2366    : is_convertible<_Ptr1, _Ptr2> {};
2367
2368template <class _Ptr1, class _Ptr2>
2369struct __same_or_less_cv_qualified_imp<_Ptr1, _Ptr2, false>
2370    : false_type {};
2371
2372template <class _Ptr1, class _Ptr2, bool = is_pointer<_Ptr1>::value ||
2373                                           is_same<_Ptr1, _Ptr2>::value ||
2374                                           __has_element_type<_Ptr1>::value>
2375struct __same_or_less_cv_qualified
2376    : __same_or_less_cv_qualified_imp<_Ptr1, _Ptr2> {};
2377
2378template <class _Ptr1, class _Ptr2>
2379struct __same_or_less_cv_qualified<_Ptr1, _Ptr2, false>
2380    : false_type {};
2381
2382// default_delete
2383
2384template <class _Tp>
2385struct _LIBCPP_TEMPLATE_VIS default_delete
2386{
2387#ifndef _LIBCPP_CXX03_LANG
2388    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT = default;
2389#else
2390    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT {}
2391#endif
2392    template <class _Up>
2393        _LIBCPP_INLINE_VISIBILITY default_delete(const default_delete<_Up>&,
2394             typename enable_if<is_convertible<_Up*, _Tp*>::value>::type* = 0) _NOEXCEPT {}
2395    _LIBCPP_INLINE_VISIBILITY void operator() (_Tp* __ptr) const _NOEXCEPT
2396        {
2397            static_assert(sizeof(_Tp) > 0, "default_delete can not delete incomplete type");
2398            static_assert(!is_void<_Tp>::value, "default_delete can not delete incomplete type");
2399            delete __ptr;
2400        }
2401};
2402
2403template <class _Tp>
2404struct _LIBCPP_TEMPLATE_VIS default_delete<_Tp[]>
2405{
2406public:
2407#ifndef _LIBCPP_CXX03_LANG
2408    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT = default;
2409#else
2410    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR default_delete() _NOEXCEPT {}
2411#endif
2412    template <class _Up>
2413        _LIBCPP_INLINE_VISIBILITY default_delete(const default_delete<_Up[]>&,
2414             typename enable_if<__same_or_less_cv_qualified<_Up*, _Tp*>::value>::type* = 0) _NOEXCEPT {}
2415    template <class _Up>
2416        _LIBCPP_INLINE_VISIBILITY
2417        void operator() (_Up* __ptr,
2418                         typename enable_if<__same_or_less_cv_qualified<_Up*, _Tp*>::value>::type* = 0) const _NOEXCEPT
2419        {
2420            static_assert(sizeof(_Tp) > 0, "default_delete can not delete incomplete type");
2421            static_assert(!is_void<_Tp>::value, "default_delete can not delete void type");
2422            delete [] __ptr;
2423        }
2424};
2425
2426template <class _Tp, class _Dp = default_delete<_Tp> >
2427class _LIBCPP_TEMPLATE_VIS unique_ptr
2428{
2429public:
2430    typedef _Tp element_type;
2431    typedef _Dp deleter_type;
2432    typedef typename __pointer_type<_Tp, deleter_type>::type pointer;
2433private:
2434    __compressed_pair<pointer, deleter_type> __ptr_;
2435
2436#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2437    unique_ptr(unique_ptr&);
2438    template <class _Up, class _Ep>
2439        unique_ptr(unique_ptr<_Up, _Ep>&);
2440    unique_ptr& operator=(unique_ptr&);
2441    template <class _Up, class _Ep>
2442        unique_ptr& operator=(unique_ptr<_Up, _Ep>&);
2443#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2444
2445    struct __nat {int __for_bool_;};
2446
2447    typedef       typename remove_reference<deleter_type>::type& _Dp_reference;
2448    typedef const typename remove_reference<deleter_type>::type& _Dp_const_reference;
2449public:
2450    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT
2451        : __ptr_(pointer())
2452        {
2453            static_assert(!is_pointer<deleter_type>::value,
2454                "unique_ptr constructed with null function pointer deleter");
2455        }
2456    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT
2457        : __ptr_(pointer())
2458        {
2459            static_assert(!is_pointer<deleter_type>::value,
2460                "unique_ptr constructed with null function pointer deleter");
2461        }
2462    _LIBCPP_INLINE_VISIBILITY explicit unique_ptr(pointer __p) _NOEXCEPT
2463        : __ptr_(_VSTD::move(__p))
2464        {
2465            static_assert(!is_pointer<deleter_type>::value,
2466                "unique_ptr constructed with null function pointer deleter");
2467        }
2468
2469#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2470    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, typename conditional<
2471                                        is_reference<deleter_type>::value,
2472                                        deleter_type,
2473                                        typename add_lvalue_reference<const deleter_type>::type>::type __d)
2474             _NOEXCEPT
2475        : __ptr_(__p, __d) {}
2476
2477    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, typename remove_reference<deleter_type>::type&& __d)
2478             _NOEXCEPT
2479        : __ptr_(__p, _VSTD::move(__d))
2480        {
2481            static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
2482        }
2483    _LIBCPP_INLINE_VISIBILITY unique_ptr(unique_ptr&& __u) _NOEXCEPT
2484        : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
2485    template <class _Up, class _Ep>
2486        _LIBCPP_INLINE_VISIBILITY
2487        unique_ptr(unique_ptr<_Up, _Ep>&& __u,
2488                   typename enable_if
2489                      <
2490                        !is_array<_Up>::value &&
2491                         is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2492                         is_convertible<_Ep, deleter_type>::value &&
2493                         (
2494                            !is_reference<deleter_type>::value ||
2495                            is_same<deleter_type, _Ep>::value
2496                         ),
2497                         __nat
2498                      >::type = __nat()) _NOEXCEPT
2499            : __ptr_(__u.release(), _VSTD::forward<_Ep>(__u.get_deleter())) {}
2500
2501#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
2502    template <class _Up>
2503        _LIBCPP_INLINE_VISIBILITY unique_ptr(auto_ptr<_Up>&& __p,
2504                typename enable_if<
2505                                      is_convertible<_Up*, _Tp*>::value &&
2506                                      is_same<_Dp, default_delete<_Tp> >::value,
2507                                      __nat
2508                                  >::type = __nat()) _NOEXCEPT
2509            : __ptr_(__p.release())
2510            {
2511            }
2512#endif
2513
2514        _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT
2515            {
2516                reset(__u.release());
2517                __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
2518                return *this;
2519            }
2520
2521        template <class _Up, class _Ep>
2522            _LIBCPP_INLINE_VISIBILITY
2523            typename enable_if
2524            <
2525                !is_array<_Up>::value &&
2526                is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2527                is_assignable<deleter_type&, _Ep&&>::value,
2528                unique_ptr&
2529            >::type
2530            operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
2531            {
2532                reset(__u.release());
2533                __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2534                return *this;
2535            }
2536#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2537
2538    _LIBCPP_INLINE_VISIBILITY operator __rv<unique_ptr>()
2539    {
2540        return __rv<unique_ptr>(*this);
2541    }
2542
2543    _LIBCPP_INLINE_VISIBILITY unique_ptr(__rv<unique_ptr> __u)
2544        : __ptr_(__u->release(), _VSTD::forward<deleter_type>(__u->get_deleter())) {}
2545
2546    template <class _Up, class _Ep>
2547    _LIBCPP_INLINE_VISIBILITY
2548    typename enable_if<
2549        !is_array<_Up>::value &&
2550        is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2551        is_assignable<deleter_type&, _Ep&>::value,
2552        unique_ptr&
2553    >::type
2554    operator=(unique_ptr<_Up, _Ep> __u)
2555    {
2556        reset(__u.release());
2557        __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2558        return *this;
2559    }
2560
2561    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, deleter_type __d)
2562        : __ptr_(_VSTD::move(__p), _VSTD::move(__d)) {}
2563
2564#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
2565    template <class _Up>
2566        _LIBCPP_INLINE_VISIBILITY
2567                typename enable_if<
2568                                      is_convertible<_Up*, _Tp*>::value &&
2569                                      is_same<_Dp, default_delete<_Tp> >::value,
2570                                      unique_ptr&
2571                                  >::type
2572        operator=(auto_ptr<_Up> __p)
2573            {reset(__p.release()); return *this;}
2574#endif
2575#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2576    _LIBCPP_INLINE_VISIBILITY ~unique_ptr() {reset();}
2577
2578    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(nullptr_t) _NOEXCEPT
2579    {
2580        reset();
2581        return *this;
2582    }
2583
2584    _LIBCPP_INLINE_VISIBILITY typename add_lvalue_reference<_Tp>::type operator*() const
2585        {return *__ptr_.first();}
2586    _LIBCPP_INLINE_VISIBILITY pointer operator->() const _NOEXCEPT {return __ptr_.first();}
2587    _LIBCPP_INLINE_VISIBILITY pointer get() const _NOEXCEPT {return __ptr_.first();}
2588    _LIBCPP_INLINE_VISIBILITY       _Dp_reference get_deleter() _NOEXCEPT
2589        {return __ptr_.second();}
2590    _LIBCPP_INLINE_VISIBILITY _Dp_const_reference get_deleter() const _NOEXCEPT
2591        {return __ptr_.second();}
2592    _LIBCPP_INLINE_VISIBILITY
2593        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT
2594        {return __ptr_.first() != nullptr;}
2595
2596    _LIBCPP_INLINE_VISIBILITY pointer release() _NOEXCEPT
2597    {
2598        pointer __t = __ptr_.first();
2599        __ptr_.first() = pointer();
2600        return __t;
2601    }
2602
2603    _LIBCPP_INLINE_VISIBILITY void reset(pointer __p = pointer()) _NOEXCEPT
2604    {
2605        pointer __tmp = __ptr_.first();
2606        __ptr_.first() = __p;
2607        if (__tmp)
2608            __ptr_.second()(__tmp);
2609    }
2610
2611    _LIBCPP_INLINE_VISIBILITY void swap(unique_ptr& __u) _NOEXCEPT
2612        {__ptr_.swap(__u.__ptr_);}
2613};
2614
2615template <class _Tp, class _Dp>
2616class _LIBCPP_TEMPLATE_VIS unique_ptr<_Tp[], _Dp>
2617{
2618public:
2619    typedef _Tp element_type;
2620    typedef _Dp deleter_type;
2621    typedef typename __pointer_type<_Tp, deleter_type>::type pointer;
2622private:
2623    __compressed_pair<pointer, deleter_type> __ptr_;
2624
2625#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2626    unique_ptr(unique_ptr&);
2627    template <class _Up>
2628        unique_ptr(unique_ptr<_Up>&);
2629    unique_ptr& operator=(unique_ptr&);
2630    template <class _Up>
2631        unique_ptr& operator=(unique_ptr<_Up>&);
2632#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2633
2634    struct __nat {int __for_bool_;};
2635
2636    typedef       typename remove_reference<deleter_type>::type& _Dp_reference;
2637    typedef const typename remove_reference<deleter_type>::type& _Dp_const_reference;
2638public:
2639    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT
2640        : __ptr_(pointer())
2641        {
2642            static_assert(!is_pointer<deleter_type>::value,
2643                "unique_ptr constructed with null function pointer deleter");
2644        }
2645    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT
2646        : __ptr_(pointer())
2647        {
2648            static_assert(!is_pointer<deleter_type>::value,
2649                "unique_ptr constructed with null function pointer deleter");
2650        }
2651#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2652    template <class _Pp>
2653    _LIBCPP_INLINE_VISIBILITY explicit unique_ptr(_Pp __p,
2654            typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, __nat>::type = __nat()) _NOEXCEPT
2655        : __ptr_(__p)
2656        {
2657            static_assert(!is_pointer<deleter_type>::value,
2658                "unique_ptr constructed with null function pointer deleter");
2659        }
2660
2661    template <class _Pp>
2662    _LIBCPP_INLINE_VISIBILITY unique_ptr(_Pp __p, typename conditional<
2663                                       is_reference<deleter_type>::value,
2664                                       deleter_type,
2665                                       typename add_lvalue_reference<const deleter_type>::type>::type __d,
2666                                       typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, __nat>::type = __nat())
2667             _NOEXCEPT
2668        : __ptr_(__p, __d) {}
2669
2670    _LIBCPP_INLINE_VISIBILITY unique_ptr(nullptr_t, typename conditional<
2671                                       is_reference<deleter_type>::value,
2672                                       deleter_type,
2673                                       typename add_lvalue_reference<const deleter_type>::type>::type __d)
2674             _NOEXCEPT
2675        : __ptr_(pointer(), __d) {}
2676
2677    template <class _Pp>
2678    _LIBCPP_INLINE_VISIBILITY unique_ptr(_Pp __p,
2679                                         typename remove_reference<deleter_type>::type&& __d,
2680                                         typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, __nat>::type = __nat())
2681             _NOEXCEPT
2682        : __ptr_(__p, _VSTD::move(__d))
2683        {
2684            static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
2685        }
2686
2687    _LIBCPP_INLINE_VISIBILITY unique_ptr(nullptr_t, typename remove_reference<deleter_type>::type&& __d)
2688             _NOEXCEPT
2689        : __ptr_(pointer(), _VSTD::move(__d))
2690        {
2691            static_assert(!is_reference<deleter_type>::value, "rvalue deleter bound to reference");
2692        }
2693
2694    _LIBCPP_INLINE_VISIBILITY unique_ptr(unique_ptr&& __u) _NOEXCEPT
2695        : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
2696
2697    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT
2698        {
2699            reset(__u.release());
2700            __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
2701            return *this;
2702        }
2703
2704    template <class _Up, class _Ep>
2705        _LIBCPP_INLINE_VISIBILITY
2706        unique_ptr(unique_ptr<_Up, _Ep>&& __u,
2707                   typename enable_if
2708                            <
2709                                is_array<_Up>::value &&
2710                                __same_or_less_cv_qualified<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value
2711                                && is_convertible<_Ep, deleter_type>::value &&
2712                                (
2713                                    !is_reference<deleter_type>::value ||
2714                                    is_same<deleter_type, _Ep>::value
2715                                ),
2716                                __nat
2717                            >::type = __nat()
2718                  ) _NOEXCEPT
2719        : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {}
2720
2721
2722        template <class _Up, class _Ep>
2723            _LIBCPP_INLINE_VISIBILITY
2724            typename enable_if
2725            <
2726                is_array<_Up>::value &&
2727                __same_or_less_cv_qualified<typename unique_ptr<_Up, _Ep>::pointer, pointer>::value &&
2728                is_assignable<deleter_type&, _Ep&&>::value,
2729                unique_ptr&
2730            >::type
2731            operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
2732            {
2733                reset(__u.release());
2734                __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2735                return *this;
2736            }
2737#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2738
2739    _LIBCPP_INLINE_VISIBILITY explicit unique_ptr(pointer __p)
2740        : __ptr_(__p)
2741        {
2742            static_assert(!is_pointer<deleter_type>::value,
2743                "unique_ptr constructed with null function pointer deleter");
2744        }
2745
2746    _LIBCPP_INLINE_VISIBILITY unique_ptr(pointer __p, deleter_type __d)
2747        : __ptr_(__p, _VSTD::forward<deleter_type>(__d)) {}
2748
2749    _LIBCPP_INLINE_VISIBILITY unique_ptr(nullptr_t, deleter_type __d)
2750        : __ptr_(pointer(), _VSTD::forward<deleter_type>(__d)) {}
2751
2752    _LIBCPP_INLINE_VISIBILITY operator __rv<unique_ptr>()
2753    {
2754        return __rv<unique_ptr>(*this);
2755    }
2756
2757    _LIBCPP_INLINE_VISIBILITY unique_ptr(__rv<unique_ptr> __u)
2758        : __ptr_(__u->release(), _VSTD::forward<deleter_type>(__u->get_deleter())) {}
2759
2760    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(__rv<unique_ptr> __u)
2761    {
2762        reset(__u->release());
2763        __ptr_.second() = _VSTD::forward<deleter_type>(__u->get_deleter());
2764        return *this;
2765    }
2766
2767#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2768    _LIBCPP_INLINE_VISIBILITY ~unique_ptr() {reset();}
2769
2770    _LIBCPP_INLINE_VISIBILITY unique_ptr& operator=(nullptr_t) _NOEXCEPT
2771    {
2772        reset();
2773        return *this;
2774    }
2775
2776    _LIBCPP_INLINE_VISIBILITY typename add_lvalue_reference<_Tp>::type operator[](size_t __i) const
2777        {return __ptr_.first()[__i];}
2778    _LIBCPP_INLINE_VISIBILITY pointer get() const _NOEXCEPT {return __ptr_.first();}
2779    _LIBCPP_INLINE_VISIBILITY       _Dp_reference get_deleter() _NOEXCEPT
2780        {return __ptr_.second();}
2781    _LIBCPP_INLINE_VISIBILITY _Dp_const_reference get_deleter() const _NOEXCEPT
2782        {return __ptr_.second();}
2783    _LIBCPP_INLINE_VISIBILITY
2784        _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT
2785        {return __ptr_.first() != nullptr;}
2786
2787    _LIBCPP_INLINE_VISIBILITY pointer release() _NOEXCEPT
2788    {
2789        pointer __t = __ptr_.first();
2790        __ptr_.first() = pointer();
2791        return __t;
2792    }
2793
2794    template <class _Pp>
2795    _LIBCPP_INLINE_VISIBILITY
2796    typename enable_if<__same_or_less_cv_qualified<_Pp, pointer>::value, void>::type
2797    reset(_Pp __p) _NOEXCEPT
2798    {
2799        pointer __tmp = __ptr_.first();
2800        __ptr_.first() = __p;
2801        if (__tmp)
2802            __ptr_.second()(__tmp);
2803    }
2804    _LIBCPP_INLINE_VISIBILITY void reset(nullptr_t = nullptr) _NOEXCEPT
2805    {
2806        pointer __tmp = __ptr_.first();
2807        __ptr_.first() = nullptr;
2808        if (__tmp)
2809            __ptr_.second()(__tmp);
2810    }
2811
2812    _LIBCPP_INLINE_VISIBILITY void swap(unique_ptr& __u) {__ptr_.swap(__u.__ptr_);}
2813private:
2814
2815#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2816    template <class _Up>
2817        explicit unique_ptr(_Up);
2818    template <class _Up>
2819        unique_ptr(_Up __u,
2820                   typename conditional<
2821                                       is_reference<deleter_type>::value,
2822                                       deleter_type,
2823                                       typename add_lvalue_reference<const deleter_type>::type>::type,
2824                   typename enable_if
2825                      <
2826                         is_convertible<_Up, pointer>::value,
2827                         __nat
2828                      >::type = __nat());
2829#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
2830};
2831
2832template <class _Tp, class _Dp>
2833inline _LIBCPP_INLINE_VISIBILITY
2834typename enable_if<
2835    __is_swappable<_Dp>::value,
2836    void
2837>::type
2838swap(unique_ptr<_Tp, _Dp>& __x, unique_ptr<_Tp, _Dp>& __y) _NOEXCEPT {__x.swap(__y);}
2839
2840template <class _T1, class _D1, class _T2, class _D2>
2841inline _LIBCPP_INLINE_VISIBILITY
2842bool
2843operator==(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __x.get() == __y.get();}
2844
2845template <class _T1, class _D1, class _T2, class _D2>
2846inline _LIBCPP_INLINE_VISIBILITY
2847bool
2848operator!=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x == __y);}
2849
2850template <class _T1, class _D1, class _T2, class _D2>
2851inline _LIBCPP_INLINE_VISIBILITY
2852bool
2853operator< (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y)
2854{
2855    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
2856    typedef typename unique_ptr<_T2, _D2>::pointer _P2;
2857    typedef typename common_type<_P1, _P2>::type _Vp;
2858    return less<_Vp>()(__x.get(), __y.get());
2859}
2860
2861template <class _T1, class _D1, class _T2, class _D2>
2862inline _LIBCPP_INLINE_VISIBILITY
2863bool
2864operator> (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __y < __x;}
2865
2866template <class _T1, class _D1, class _T2, class _D2>
2867inline _LIBCPP_INLINE_VISIBILITY
2868bool
2869operator<=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__y < __x);}
2870
2871template <class _T1, class _D1, class _T2, class _D2>
2872inline _LIBCPP_INLINE_VISIBILITY
2873bool
2874operator>=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x < __y);}
2875
2876template <class _T1, class _D1>
2877inline _LIBCPP_INLINE_VISIBILITY
2878bool
2879operator==(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
2880{
2881    return !__x;
2882}
2883
2884template <class _T1, class _D1>
2885inline _LIBCPP_INLINE_VISIBILITY
2886bool
2887operator==(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
2888{
2889    return !__x;
2890}
2891
2892template <class _T1, class _D1>
2893inline _LIBCPP_INLINE_VISIBILITY
2894bool
2895operator!=(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
2896{
2897    return static_cast<bool>(__x);
2898}
2899
2900template <class _T1, class _D1>
2901inline _LIBCPP_INLINE_VISIBILITY
2902bool
2903operator!=(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
2904{
2905    return static_cast<bool>(__x);
2906}
2907
2908template <class _T1, class _D1>
2909inline _LIBCPP_INLINE_VISIBILITY
2910bool
2911operator<(const unique_ptr<_T1, _D1>& __x, nullptr_t)
2912{
2913    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
2914    return less<_P1>()(__x.get(), nullptr);
2915}
2916
2917template <class _T1, class _D1>
2918inline _LIBCPP_INLINE_VISIBILITY
2919bool
2920operator<(nullptr_t, const unique_ptr<_T1, _D1>& __x)
2921{
2922    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
2923    return less<_P1>()(nullptr, __x.get());
2924}
2925
2926template <class _T1, class _D1>
2927inline _LIBCPP_INLINE_VISIBILITY
2928bool
2929operator>(const unique_ptr<_T1, _D1>& __x, nullptr_t)
2930{
2931    return nullptr < __x;
2932}
2933
2934template <class _T1, class _D1>
2935inline _LIBCPP_INLINE_VISIBILITY
2936bool
2937operator>(nullptr_t, const unique_ptr<_T1, _D1>& __x)
2938{
2939    return __x < nullptr;
2940}
2941
2942template <class _T1, class _D1>
2943inline _LIBCPP_INLINE_VISIBILITY
2944bool
2945operator<=(const unique_ptr<_T1, _D1>& __x, nullptr_t)
2946{
2947    return !(nullptr < __x);
2948}
2949
2950template <class _T1, class _D1>
2951inline _LIBCPP_INLINE_VISIBILITY
2952bool
2953operator<=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
2954{
2955    return !(__x < nullptr);
2956}
2957
2958template <class _T1, class _D1>
2959inline _LIBCPP_INLINE_VISIBILITY
2960bool
2961operator>=(const unique_ptr<_T1, _D1>& __x, nullptr_t)
2962{
2963    return !(__x < nullptr);
2964}
2965
2966template <class _T1, class _D1>
2967inline _LIBCPP_INLINE_VISIBILITY
2968bool
2969operator>=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
2970{
2971    return !(nullptr < __x);
2972}
2973
2974#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
2975
2976template <class _Tp, class _Dp>
2977inline _LIBCPP_INLINE_VISIBILITY
2978unique_ptr<_Tp, _Dp>
2979move(unique_ptr<_Tp, _Dp>& __t)
2980{
2981    return unique_ptr<_Tp, _Dp>(__rv<unique_ptr<_Tp, _Dp> >(__t));
2982}
2983
2984#endif
2985
2986#if _LIBCPP_STD_VER > 11
2987
2988template<class _Tp>
2989struct __unique_if
2990{
2991    typedef unique_ptr<_Tp> __unique_single;
2992};
2993
2994template<class _Tp>
2995struct __unique_if<_Tp[]>
2996{
2997    typedef unique_ptr<_Tp[]> __unique_array_unknown_bound;
2998};
2999
3000template<class _Tp, size_t _Np>
3001struct __unique_if<_Tp[_Np]>
3002{
3003    typedef void __unique_array_known_bound;
3004};
3005
3006template<class _Tp, class... _Args>
3007inline _LIBCPP_INLINE_VISIBILITY
3008typename __unique_if<_Tp>::__unique_single
3009make_unique(_Args&&... __args)
3010{
3011    return unique_ptr<_Tp>(new _Tp(_VSTD::forward<_Args>(__args)...));
3012}
3013
3014template<class _Tp>
3015inline _LIBCPP_INLINE_VISIBILITY
3016typename __unique_if<_Tp>::__unique_array_unknown_bound
3017make_unique(size_t __n)
3018{
3019    typedef typename remove_extent<_Tp>::type _Up;
3020    return unique_ptr<_Tp>(new _Up[__n]());
3021}
3022
3023template<class _Tp, class... _Args>
3024    typename __unique_if<_Tp>::__unique_array_known_bound
3025    make_unique(_Args&&...) = delete;
3026
3027#endif  // _LIBCPP_STD_VER > 11
3028
3029template <class _Tp, class _Dp>
3030#ifdef _LIBCPP_CXX03_LANG
3031struct _LIBCPP_TEMPLATE_VIS hash<unique_ptr<_Tp, _Dp> >
3032#else
3033struct _LIBCPP_TEMPLATE_VIS hash<__enable_hash_helper<
3034    unique_ptr<_Tp, _Dp>, typename unique_ptr<_Tp, _Dp>::pointer>>
3035#endif
3036{
3037    typedef unique_ptr<_Tp, _Dp> argument_type;
3038    typedef size_t               result_type;
3039    _LIBCPP_INLINE_VISIBILITY
3040    result_type operator()(const argument_type& __ptr) const _NOEXCEPT
3041    {
3042        typedef typename argument_type::pointer pointer;
3043        return hash<pointer>()(__ptr.get());
3044    }
3045};
3046
3047struct __destruct_n
3048{
3049private:
3050    size_t size;
3051
3052    template <class _Tp>
3053    _LIBCPP_INLINE_VISIBILITY void __process(_Tp* __p, false_type) _NOEXCEPT
3054        {for (size_t __i = 0; __i < size; ++__i, ++__p) __p->~_Tp();}
3055
3056    template <class _Tp>
3057    _LIBCPP_INLINE_VISIBILITY void __process(_Tp*, true_type) _NOEXCEPT
3058        {}
3059
3060    _LIBCPP_INLINE_VISIBILITY void __incr(false_type) _NOEXCEPT
3061        {++size;}
3062    _LIBCPP_INLINE_VISIBILITY void __incr(true_type) _NOEXCEPT
3063        {}
3064
3065    _LIBCPP_INLINE_VISIBILITY void __set(size_t __s, false_type) _NOEXCEPT
3066        {size = __s;}
3067    _LIBCPP_INLINE_VISIBILITY void __set(size_t, true_type) _NOEXCEPT
3068        {}
3069public:
3070    _LIBCPP_INLINE_VISIBILITY explicit __destruct_n(size_t __s) _NOEXCEPT
3071        : size(__s) {}
3072
3073    template <class _Tp>
3074    _LIBCPP_INLINE_VISIBILITY void __incr(_Tp*) _NOEXCEPT
3075        {__incr(integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3076
3077    template <class _Tp>
3078    _LIBCPP_INLINE_VISIBILITY void __set(size_t __s, _Tp*) _NOEXCEPT
3079        {__set(__s, integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3080
3081    template <class _Tp>
3082    _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) _NOEXCEPT
3083        {__process(__p, integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3084};
3085
3086template <class _Alloc>
3087class __allocator_destructor
3088{
3089    typedef allocator_traits<_Alloc> __alloc_traits;
3090public:
3091    typedef typename __alloc_traits::pointer pointer;
3092    typedef typename __alloc_traits::size_type size_type;
3093private:
3094    _Alloc& __alloc_;
3095    size_type __s_;
3096public:
3097    _LIBCPP_INLINE_VISIBILITY __allocator_destructor(_Alloc& __a, size_type __s)
3098             _NOEXCEPT
3099        : __alloc_(__a), __s_(__s) {}
3100    _LIBCPP_INLINE_VISIBILITY
3101    void operator()(pointer __p) _NOEXCEPT
3102        {__alloc_traits::deallocate(__alloc_, __p, __s_);}
3103};
3104
3105template <class _InputIterator, class _ForwardIterator>
3106_ForwardIterator
3107uninitialized_copy(_InputIterator __f, _InputIterator __l, _ForwardIterator __r)
3108{
3109    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3110#ifndef _LIBCPP_NO_EXCEPTIONS
3111    _ForwardIterator __s = __r;
3112    try
3113    {
3114#endif
3115        for (; __f != __l; ++__f, (void) ++__r)
3116            ::new (static_cast<void*>(_VSTD::addressof(*__r))) value_type(*__f);
3117#ifndef _LIBCPP_NO_EXCEPTIONS
3118    }
3119    catch (...)
3120    {
3121        for (; __s != __r; ++__s)
3122            __s->~value_type();
3123        throw;
3124    }
3125#endif
3126    return __r;
3127}
3128
3129template <class _InputIterator, class _Size, class _ForwardIterator>
3130_ForwardIterator
3131uninitialized_copy_n(_InputIterator __f, _Size __n, _ForwardIterator __r)
3132{
3133    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3134#ifndef _LIBCPP_NO_EXCEPTIONS
3135    _ForwardIterator __s = __r;
3136    try
3137    {
3138#endif
3139        for (; __n > 0; ++__f, (void) ++__r, (void) --__n)
3140            ::new (static_cast<void*>(_VSTD::addressof(*__r))) value_type(*__f);
3141#ifndef _LIBCPP_NO_EXCEPTIONS
3142    }
3143    catch (...)
3144    {
3145        for (; __s != __r; ++__s)
3146            __s->~value_type();
3147        throw;
3148    }
3149#endif
3150    return __r;
3151}
3152
3153template <class _ForwardIterator, class _Tp>
3154void
3155uninitialized_fill(_ForwardIterator __f, _ForwardIterator __l, const _Tp& __x)
3156{
3157    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3158#ifndef _LIBCPP_NO_EXCEPTIONS
3159    _ForwardIterator __s = __f;
3160    try
3161    {
3162#endif
3163        for (; __f != __l; ++__f)
3164            ::new (static_cast<void*>(_VSTD::addressof(*__f))) value_type(__x);
3165#ifndef _LIBCPP_NO_EXCEPTIONS
3166    }
3167    catch (...)
3168    {
3169        for (; __s != __f; ++__s)
3170            __s->~value_type();
3171        throw;
3172    }
3173#endif
3174}
3175
3176template <class _ForwardIterator, class _Size, class _Tp>
3177_ForwardIterator
3178uninitialized_fill_n(_ForwardIterator __f, _Size __n, const _Tp& __x)
3179{
3180    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3181#ifndef _LIBCPP_NO_EXCEPTIONS
3182    _ForwardIterator __s = __f;
3183    try
3184    {
3185#endif
3186        for (; __n > 0; ++__f, (void) --__n)
3187            ::new (static_cast<void*>(_VSTD::addressof(*__f))) value_type(__x);
3188#ifndef _LIBCPP_NO_EXCEPTIONS
3189    }
3190    catch (...)
3191    {
3192        for (; __s != __f; ++__s)
3193            __s->~value_type();
3194        throw;
3195    }
3196#endif
3197    return __f;
3198}
3199
3200#if _LIBCPP_STD_VER > 14
3201
3202template <class _Tp>
3203inline _LIBCPP_INLINE_VISIBILITY
3204void destroy_at(_Tp* __loc) {
3205    _LIBCPP_ASSERT(__loc, "null pointer given to destroy_at");
3206    __loc->~_Tp();
3207}
3208
3209template <class _ForwardIterator>
3210inline _LIBCPP_INLINE_VISIBILITY
3211void destroy(_ForwardIterator __first, _ForwardIterator __last) {
3212    for (; __first != __last; ++__first)
3213        _VSTD::destroy_at(_VSTD::addressof(*__first));
3214}
3215
3216template <class _ForwardIterator, class _Size>
3217inline _LIBCPP_INLINE_VISIBILITY
3218_ForwardIterator destroy_n(_ForwardIterator __first, _Size __n) {
3219    for (; __n > 0; (void)++__first, --__n)
3220        _VSTD::destroy_at(_VSTD::addressof(*__first));
3221    return __first;
3222}
3223
3224template <class _ForwardIterator>
3225inline _LIBCPP_INLINE_VISIBILITY
3226void uninitialized_default_construct(_ForwardIterator __first, _ForwardIterator __last) {
3227    using _Vt = typename iterator_traits<_ForwardIterator>::value_type;
3228    auto __idx = __first;
3229#ifndef _LIBCPP_NO_EXCEPTIONS
3230    try {
3231#endif
3232    for (; __idx != __last; ++__idx)
3233        ::new((void*)_VSTD::addressof(*__idx)) _Vt;
3234#ifndef _LIBCPP_NO_EXCEPTIONS
3235    } catch (...) {
3236        _VSTD::destroy(__first, __idx);
3237        throw;
3238    }
3239#endif
3240}
3241
3242template <class _ForwardIterator, class _Size>
3243inline _LIBCPP_INLINE_VISIBILITY
3244_ForwardIterator uninitialized_default_construct_n(_ForwardIterator __first, _Size __n) {
3245    using _Vt = typename iterator_traits<_ForwardIterator>::value_type;
3246    auto __idx = __first;
3247#ifndef _LIBCPP_NO_EXCEPTIONS
3248    try {
3249#endif
3250    for (; __n > 0; (void)++__idx, --__n)
3251        ::new((void*)_VSTD::addressof(*__idx)) _Vt;
3252    return __idx;
3253#ifndef _LIBCPP_NO_EXCEPTIONS
3254    } catch (...) {
3255        _VSTD::destroy(__first, __idx);
3256        throw;
3257    }
3258#endif
3259}
3260
3261
3262template <class _ForwardIterator>
3263inline _LIBCPP_INLINE_VISIBILITY
3264void uninitialized_value_construct(_ForwardIterator __first, _ForwardIterator __last) {
3265    using _Vt = typename iterator_traits<_ForwardIterator>::value_type;
3266    auto __idx = __first;
3267#ifndef _LIBCPP_NO_EXCEPTIONS
3268    try {
3269#endif
3270    for (; __idx != __last; ++__idx)
3271        ::new((void*)_VSTD::addressof(*__idx)) _Vt();
3272#ifndef _LIBCPP_NO_EXCEPTIONS
3273    } catch (...) {
3274        _VSTD::destroy(__first, __idx);
3275        throw;
3276    }
3277#endif
3278}
3279
3280template <class _ForwardIterator, class _Size>
3281inline _LIBCPP_INLINE_VISIBILITY
3282_ForwardIterator uninitialized_value_construct_n(_ForwardIterator __first, _Size __n) {
3283    using _Vt = typename iterator_traits<_ForwardIterator>::value_type;
3284    auto __idx = __first;
3285#ifndef _LIBCPP_NO_EXCEPTIONS
3286    try {
3287#endif
3288    for (; __n > 0; (void)++__idx, --__n)
3289        ::new((void*)_VSTD::addressof(*__idx)) _Vt();
3290    return __idx;
3291#ifndef _LIBCPP_NO_EXCEPTIONS
3292    } catch (...) {
3293        _VSTD::destroy(__first, __idx);
3294        throw;
3295    }
3296#endif
3297}
3298
3299
3300template <class _InputIt, class _ForwardIt>
3301inline _LIBCPP_INLINE_VISIBILITY
3302_ForwardIt uninitialized_move(_InputIt __first, _InputIt __last, _ForwardIt __first_res) {
3303    using _Vt = typename iterator_traits<_ForwardIt>::value_type;
3304    auto __idx = __first_res;
3305#ifndef _LIBCPP_NO_EXCEPTIONS
3306    try {
3307#endif
3308    for (; __first != __last; (void)++__idx, ++__first)
3309        ::new((void*)_VSTD::addressof(*__idx)) _Vt(std::move(*__first));
3310    return __idx;
3311#ifndef _LIBCPP_NO_EXCEPTIONS
3312    } catch (...) {
3313        _VSTD::destroy(__first_res, __idx);
3314        throw;
3315    }
3316#endif
3317}
3318
3319template <class _InputIt, class _Size, class _ForwardIt>
3320inline _LIBCPP_INLINE_VISIBILITY
3321pair<_InputIt, _ForwardIt>
3322uninitialized_move_n(_InputIt __first, _Size __n, _ForwardIt __first_res) {
3323    using _Vt = typename iterator_traits<_ForwardIt>::value_type;
3324    auto __idx = __first_res;
3325#ifndef _LIBCPP_NO_EXCEPTIONS
3326    try {
3327#endif
3328    for (; __n > 0; ++__idx, (void)++__first, --__n)
3329        ::new((void*)_VSTD::addressof(*__idx)) _Vt(std::move(*__first));
3330    return {__first, __idx};
3331#ifndef _LIBCPP_NO_EXCEPTIONS
3332    } catch (...) {
3333        _VSTD::destroy(__first_res, __idx);
3334        throw;
3335    }
3336#endif
3337}
3338
3339
3340#endif // _LIBCPP_STD_VER > 14
3341
3342// NOTE: Relaxed and acq/rel atomics (for increment and decrement respectively)
3343// should be sufficient for thread safety.
3344// See https://bugs.llvm.org/show_bug.cgi?id=22803
3345#if defined(__clang__) && __has_builtin(__atomic_add_fetch)          \
3346                       && defined(__ATOMIC_RELAXED)                  \
3347                       && defined(__ATOMIC_ACQ_REL)
3348#   define _LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT
3349#elif !defined(__clang__) && defined(_GNUC_VER) && _GNUC_VER >= 407
3350#   define _LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT
3351#endif
3352
3353template <class _Tp>
3354inline _LIBCPP_INLINE_VISIBILITY _Tp
3355__libcpp_atomic_refcount_increment(_Tp& __t) _NOEXCEPT
3356{
3357#if defined(_LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT) && !defined(_LIBCPP_HAS_NO_THREADS)
3358    return __atomic_add_fetch(&__t, 1, __ATOMIC_RELAXED);
3359#else
3360    return __t += 1;
3361#endif
3362}
3363
3364template <class _Tp>
3365inline _LIBCPP_INLINE_VISIBILITY _Tp
3366__libcpp_atomic_refcount_decrement(_Tp& __t) _NOEXCEPT
3367{
3368#if defined(_LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT) && !defined(_LIBCPP_HAS_NO_THREADS)
3369    return __atomic_add_fetch(&__t, -1, __ATOMIC_ACQ_REL);
3370#else
3371    return __t -= 1;
3372#endif
3373}
3374
3375class _LIBCPP_EXCEPTION_ABI bad_weak_ptr
3376    : public std::exception
3377{
3378public:
3379    virtual ~bad_weak_ptr() _NOEXCEPT;
3380    virtual const char* what() const  _NOEXCEPT;
3381};
3382
3383_LIBCPP_NORETURN inline _LIBCPP_ALWAYS_INLINE
3384void __throw_bad_weak_ptr()
3385{
3386#ifndef _LIBCPP_NO_EXCEPTIONS
3387    throw bad_weak_ptr();
3388#else
3389    _VSTD::abort();
3390#endif
3391}
3392
3393template<class _Tp> class _LIBCPP_TEMPLATE_VIS weak_ptr;
3394
3395class _LIBCPP_TYPE_VIS __shared_count
3396{
3397    __shared_count(const __shared_count&);
3398    __shared_count& operator=(const __shared_count&);
3399
3400protected:
3401    long __shared_owners_;
3402    virtual ~__shared_count();
3403private:
3404    virtual void __on_zero_shared() _NOEXCEPT = 0;
3405
3406public:
3407    _LIBCPP_INLINE_VISIBILITY
3408    explicit __shared_count(long __refs = 0) _NOEXCEPT
3409        : __shared_owners_(__refs) {}
3410
3411#if defined(_LIBCPP_BUILDING_MEMORY) && \
3412    defined(_LIBCPP_DEPRECATED_ABI_LEGACY_LIBRARY_DEFINITIONS_FOR_INLINE_FUNCTIONS)
3413    void __add_shared() _NOEXCEPT;
3414    bool __release_shared() _NOEXCEPT;
3415#else
3416    _LIBCPP_INLINE_VISIBILITY
3417    void __add_shared() _NOEXCEPT {
3418      __libcpp_atomic_refcount_increment(__shared_owners_);
3419    }
3420    _LIBCPP_INLINE_VISIBILITY
3421    bool __release_shared() _NOEXCEPT {
3422      if (__libcpp_atomic_refcount_decrement(__shared_owners_) == -1) {
3423        __on_zero_shared();
3424        return true;
3425      }
3426      return false;
3427    }
3428#endif
3429    _LIBCPP_INLINE_VISIBILITY
3430    long use_count() const _NOEXCEPT {
3431        return __libcpp_relaxed_load(&__shared_owners_) + 1;
3432    }
3433};
3434
3435class _LIBCPP_TYPE_VIS __shared_weak_count
3436    : private __shared_count
3437{
3438    long __shared_weak_owners_;
3439
3440public:
3441    _LIBCPP_INLINE_VISIBILITY
3442    explicit __shared_weak_count(long __refs = 0) _NOEXCEPT
3443        : __shared_count(__refs),
3444          __shared_weak_owners_(__refs) {}
3445protected:
3446    virtual ~__shared_weak_count();
3447
3448public:
3449#if defined(_LIBCPP_BUILDING_MEMORY) && \
3450    defined(_LIBCPP_DEPRECATED_ABI_LEGACY_LIBRARY_DEFINITIONS_FOR_INLINE_FUNCTIONS)
3451    void __add_shared() _NOEXCEPT;
3452    void __add_weak() _NOEXCEPT;
3453    void __release_shared() _NOEXCEPT;
3454#else
3455    _LIBCPP_INLINE_VISIBILITY
3456    void __add_shared() _NOEXCEPT {
3457      __shared_count::__add_shared();
3458    }
3459    _LIBCPP_INLINE_VISIBILITY
3460    void __add_weak() _NOEXCEPT {
3461      __libcpp_atomic_refcount_increment(__shared_weak_owners_);
3462    }
3463    _LIBCPP_INLINE_VISIBILITY
3464    void __release_shared() _NOEXCEPT {
3465      if (__shared_count::__release_shared())
3466        __release_weak();
3467    }
3468#endif
3469    void __release_weak() _NOEXCEPT;
3470    _LIBCPP_INLINE_VISIBILITY
3471    long use_count() const _NOEXCEPT {return __shared_count::use_count();}
3472    __shared_weak_count* lock() _NOEXCEPT;
3473
3474    // Define the function out only if we build static libc++ without RTTI.
3475    // Otherwise we may break clients who need to compile their projects with
3476    // -fno-rtti and yet link against a libc++.dylib compiled
3477    // without -fno-rtti.
3478#if !defined(_LIBCPP_NO_RTTI) || !defined(_LIBCPP_BUILD_STATIC)
3479    virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
3480#endif
3481private:
3482    virtual void __on_zero_shared_weak() _NOEXCEPT = 0;
3483};
3484
3485template <class _Tp, class _Dp, class _Alloc>
3486class __shared_ptr_pointer
3487    : public __shared_weak_count
3488{
3489    __compressed_pair<__compressed_pair<_Tp, _Dp>, _Alloc> __data_;
3490public:
3491    _LIBCPP_INLINE_VISIBILITY
3492    __shared_ptr_pointer(_Tp __p, _Dp __d, _Alloc __a)
3493        :  __data_(__compressed_pair<_Tp, _Dp>(__p, _VSTD::move(__d)), _VSTD::move(__a)) {}
3494
3495#ifndef _LIBCPP_NO_RTTI
3496    virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
3497#endif
3498
3499private:
3500    virtual void __on_zero_shared() _NOEXCEPT;
3501    virtual void __on_zero_shared_weak() _NOEXCEPT;
3502};
3503
3504#ifndef _LIBCPP_NO_RTTI
3505
3506template <class _Tp, class _Dp, class _Alloc>
3507const void*
3508__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__get_deleter(const type_info& __t) const _NOEXCEPT
3509{
3510    return __t == typeid(_Dp) ? _VSTD::addressof(__data_.first().second()) : 0;
3511}
3512
3513#endif  // _LIBCPP_NO_RTTI
3514
3515template <class _Tp, class _Dp, class _Alloc>
3516void
3517__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared() _NOEXCEPT
3518{
3519    __data_.first().second()(__data_.first().first());
3520    __data_.first().second().~_Dp();
3521}
3522
3523template <class _Tp, class _Dp, class _Alloc>
3524void
3525__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
3526{
3527    typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_pointer>::type _Al;
3528    typedef allocator_traits<_Al> _ATraits;
3529    typedef pointer_traits<typename _ATraits::pointer> _PTraits;
3530
3531    _Al __a(__data_.second());
3532    __data_.second().~_Alloc();
3533    __a.deallocate(_PTraits::pointer_to(*this), 1);
3534}
3535
3536template <class _Tp, class _Alloc>
3537class __shared_ptr_emplace
3538    : public __shared_weak_count
3539{
3540    __compressed_pair<_Alloc, _Tp> __data_;
3541public:
3542#ifndef _LIBCPP_HAS_NO_VARIADICS
3543
3544    _LIBCPP_INLINE_VISIBILITY
3545    __shared_ptr_emplace(_Alloc __a)
3546        :  __data_(_VSTD::move(__a)) {}
3547
3548    template <class ..._Args>
3549        _LIBCPP_INLINE_VISIBILITY
3550        __shared_ptr_emplace(_Alloc __a, _Args&& ...__args)
3551            :  __data_(piecewise_construct, _VSTD::forward_as_tuple(__a),
3552                   _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...)) {}
3553
3554#else  // _LIBCPP_HAS_NO_VARIADICS
3555
3556    _LIBCPP_INLINE_VISIBILITY
3557    __shared_ptr_emplace(_Alloc __a)
3558        :  __data_(__a) {}
3559
3560    template <class _A0>
3561        _LIBCPP_INLINE_VISIBILITY
3562        __shared_ptr_emplace(_Alloc __a, _A0& __a0)
3563            :  __data_(__a, _Tp(__a0)) {}
3564
3565    template <class _A0, class _A1>
3566        _LIBCPP_INLINE_VISIBILITY
3567        __shared_ptr_emplace(_Alloc __a, _A0& __a0, _A1& __a1)
3568            :  __data_(__a, _Tp(__a0, __a1)) {}
3569
3570    template <class _A0, class _A1, class _A2>
3571        _LIBCPP_INLINE_VISIBILITY
3572        __shared_ptr_emplace(_Alloc __a, _A0& __a0, _A1& __a1, _A2& __a2)
3573            :  __data_(__a, _Tp(__a0, __a1, __a2)) {}
3574
3575#endif  // _LIBCPP_HAS_NO_VARIADICS
3576
3577private:
3578    virtual void __on_zero_shared() _NOEXCEPT;
3579    virtual void __on_zero_shared_weak() _NOEXCEPT;
3580public:
3581    _LIBCPP_INLINE_VISIBILITY
3582    _Tp* get() _NOEXCEPT {return &__data_.second();}
3583};
3584
3585template <class _Tp, class _Alloc>
3586void
3587__shared_ptr_emplace<_Tp, _Alloc>::__on_zero_shared() _NOEXCEPT
3588{
3589    __data_.second().~_Tp();
3590}
3591
3592template <class _Tp, class _Alloc>
3593void
3594__shared_ptr_emplace<_Tp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
3595{
3596    typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_emplace>::type _Al;
3597    typedef allocator_traits<_Al> _ATraits;
3598    typedef pointer_traits<typename _ATraits::pointer> _PTraits;
3599    _Al __a(__data_.first());
3600    __data_.first().~_Alloc();
3601    __a.deallocate(_PTraits::pointer_to(*this), 1);
3602}
3603
3604template<class _Tp> class _LIBCPP_TEMPLATE_VIS enable_shared_from_this;
3605
3606template<class _Tp>
3607class _LIBCPP_TEMPLATE_VIS shared_ptr
3608{
3609public:
3610    typedef _Tp element_type;
3611
3612#if _LIBCPP_STD_VER > 14
3613    typedef weak_ptr<_Tp> weak_type;
3614#endif
3615private:
3616    element_type*      __ptr_;
3617    __shared_weak_count* __cntrl_;
3618
3619    struct __nat {int __for_bool_;};
3620public:
3621    _LIBCPP_INLINE_VISIBILITY
3622    _LIBCPP_CONSTEXPR shared_ptr() _NOEXCEPT;
3623    _LIBCPP_INLINE_VISIBILITY
3624    _LIBCPP_CONSTEXPR shared_ptr(nullptr_t) _NOEXCEPT;
3625    template<class _Yp>
3626        explicit shared_ptr(_Yp* __p,
3627                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3628    template<class _Yp, class _Dp>
3629        shared_ptr(_Yp* __p, _Dp __d,
3630                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3631    template<class _Yp, class _Dp, class _Alloc>
3632        shared_ptr(_Yp* __p, _Dp __d, _Alloc __a,
3633                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3634    template <class _Dp> shared_ptr(nullptr_t __p, _Dp __d);
3635    template <class _Dp, class _Alloc> shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a);
3636    template<class _Yp> _LIBCPP_INLINE_VISIBILITY shared_ptr(const shared_ptr<_Yp>& __r, element_type* __p) _NOEXCEPT;
3637    _LIBCPP_INLINE_VISIBILITY
3638    shared_ptr(const shared_ptr& __r) _NOEXCEPT;
3639    template<class _Yp>
3640        _LIBCPP_INLINE_VISIBILITY
3641        shared_ptr(const shared_ptr<_Yp>& __r,
3642                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat())
3643                       _NOEXCEPT;
3644#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3645    _LIBCPP_INLINE_VISIBILITY
3646    shared_ptr(shared_ptr&& __r) _NOEXCEPT;
3647    template<class _Yp> _LIBCPP_INLINE_VISIBILITY  shared_ptr(shared_ptr<_Yp>&& __r,
3648                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat())
3649                       _NOEXCEPT;
3650#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3651    template<class _Yp> explicit shared_ptr(const weak_ptr<_Yp>& __r,
3652                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type= __nat());
3653#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
3654#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3655    template<class _Yp>
3656        shared_ptr(auto_ptr<_Yp>&& __r,
3657                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3658#else
3659    template<class _Yp>
3660        shared_ptr(auto_ptr<_Yp> __r,
3661                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3662#endif
3663#endif
3664#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3665    template <class _Yp, class _Dp>
3666        shared_ptr(unique_ptr<_Yp, _Dp>&&,
3667                   typename enable_if
3668                   <
3669                       !is_lvalue_reference<_Dp>::value &&
3670                       !is_array<_Yp>::value &&
3671                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3672                       __nat
3673                   >::type = __nat());
3674    template <class _Yp, class _Dp>
3675        shared_ptr(unique_ptr<_Yp, _Dp>&&,
3676                   typename enable_if
3677                   <
3678                       is_lvalue_reference<_Dp>::value &&
3679                       !is_array<_Yp>::value &&
3680                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3681                       __nat
3682                   >::type = __nat());
3683#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3684    template <class _Yp, class _Dp>
3685        shared_ptr(unique_ptr<_Yp, _Dp>,
3686                   typename enable_if
3687                   <
3688                       !is_lvalue_reference<_Dp>::value &&
3689                       !is_array<_Yp>::value &&
3690                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3691                       __nat
3692                   >::type = __nat());
3693    template <class _Yp, class _Dp>
3694        shared_ptr(unique_ptr<_Yp, _Dp>,
3695                   typename enable_if
3696                   <
3697                       is_lvalue_reference<_Dp>::value &&
3698                       !is_array<_Yp>::value &&
3699                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3700                       __nat
3701                   >::type = __nat());
3702#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3703
3704    ~shared_ptr();
3705
3706    _LIBCPP_INLINE_VISIBILITY
3707    shared_ptr& operator=(const shared_ptr& __r) _NOEXCEPT;
3708    template<class _Yp>
3709        typename enable_if
3710        <
3711            is_convertible<_Yp*, element_type*>::value,
3712            shared_ptr&
3713        >::type
3714        _LIBCPP_INLINE_VISIBILITY
3715        operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT;
3716#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3717    _LIBCPP_INLINE_VISIBILITY
3718    shared_ptr& operator=(shared_ptr&& __r) _NOEXCEPT;
3719    template<class _Yp>
3720        typename enable_if
3721        <
3722            is_convertible<_Yp*, element_type*>::value,
3723            shared_ptr<_Tp>&
3724        >::type
3725        _LIBCPP_INLINE_VISIBILITY
3726        operator=(shared_ptr<_Yp>&& __r);
3727#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
3728    template<class _Yp>
3729        _LIBCPP_INLINE_VISIBILITY
3730        typename enable_if
3731        <
3732            !is_array<_Yp>::value &&
3733            is_convertible<_Yp*, element_type*>::value,
3734            shared_ptr
3735        >::type&
3736        operator=(auto_ptr<_Yp>&& __r);
3737#endif
3738#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3739#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
3740    template<class _Yp>
3741        _LIBCPP_INLINE_VISIBILITY
3742        typename enable_if
3743        <
3744            !is_array<_Yp>::value &&
3745            is_convertible<_Yp*, element_type*>::value,
3746            shared_ptr&
3747        >::type
3748        operator=(auto_ptr<_Yp> __r);
3749#endif
3750#endif
3751    template <class _Yp, class _Dp>
3752        typename enable_if
3753        <
3754            !is_array<_Yp>::value &&
3755            is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3756            shared_ptr&
3757        >::type
3758#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3759        _LIBCPP_INLINE_VISIBILITY
3760        operator=(unique_ptr<_Yp, _Dp>&& __r);
3761#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3762        _LIBCPP_INLINE_VISIBILITY
3763        operator=(unique_ptr<_Yp, _Dp> __r);
3764#endif
3765
3766    _LIBCPP_INLINE_VISIBILITY
3767    void swap(shared_ptr& __r) _NOEXCEPT;
3768    _LIBCPP_INLINE_VISIBILITY
3769    void reset() _NOEXCEPT;
3770    template<class _Yp>
3771        typename enable_if
3772        <
3773            is_convertible<_Yp*, element_type*>::value,
3774            void
3775        >::type
3776        _LIBCPP_INLINE_VISIBILITY
3777        reset(_Yp* __p);
3778    template<class _Yp, class _Dp>
3779        typename enable_if
3780        <
3781            is_convertible<_Yp*, element_type*>::value,
3782            void
3783        >::type
3784        _LIBCPP_INLINE_VISIBILITY
3785        reset(_Yp* __p, _Dp __d);
3786    template<class _Yp, class _Dp, class _Alloc>
3787        typename enable_if
3788        <
3789            is_convertible<_Yp*, element_type*>::value,
3790            void
3791        >::type
3792        _LIBCPP_INLINE_VISIBILITY
3793        reset(_Yp* __p, _Dp __d, _Alloc __a);
3794
3795    _LIBCPP_INLINE_VISIBILITY
3796    element_type* get() const _NOEXCEPT {return __ptr_;}
3797    _LIBCPP_INLINE_VISIBILITY
3798    typename add_lvalue_reference<element_type>::type operator*() const _NOEXCEPT
3799        {return *__ptr_;}
3800    _LIBCPP_INLINE_VISIBILITY
3801    element_type* operator->() const _NOEXCEPT {return __ptr_;}
3802    _LIBCPP_INLINE_VISIBILITY
3803    long use_count() const _NOEXCEPT {return __cntrl_ ? __cntrl_->use_count() : 0;}
3804    _LIBCPP_INLINE_VISIBILITY
3805    bool unique() const _NOEXCEPT {return use_count() == 1;}
3806    _LIBCPP_INLINE_VISIBILITY
3807    _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {return get() != 0;}
3808    template <class _Up>
3809        _LIBCPP_INLINE_VISIBILITY
3810        bool owner_before(shared_ptr<_Up> const& __p) const
3811        {return __cntrl_ < __p.__cntrl_;}
3812    template <class _Up>
3813        _LIBCPP_INLINE_VISIBILITY
3814        bool owner_before(weak_ptr<_Up> const& __p) const
3815        {return __cntrl_ < __p.__cntrl_;}
3816    _LIBCPP_INLINE_VISIBILITY
3817    bool
3818    __owner_equivalent(const shared_ptr& __p) const
3819        {return __cntrl_ == __p.__cntrl_;}
3820
3821#ifndef _LIBCPP_NO_RTTI
3822    template <class _Dp>
3823        _LIBCPP_INLINE_VISIBILITY
3824        _Dp* __get_deleter() const _NOEXCEPT
3825            {return (_Dp*)(__cntrl_ ? __cntrl_->__get_deleter(typeid(_Dp)) : 0);}
3826#endif  // _LIBCPP_NO_RTTI
3827
3828#ifndef _LIBCPP_HAS_NO_VARIADICS
3829
3830    template<class ..._Args>
3831        static
3832        shared_ptr<_Tp>
3833        make_shared(_Args&& ...__args);
3834
3835    template<class _Alloc, class ..._Args>
3836        static
3837        shared_ptr<_Tp>
3838        allocate_shared(const _Alloc& __a, _Args&& ...__args);
3839
3840#else  // _LIBCPP_HAS_NO_VARIADICS
3841
3842    static shared_ptr<_Tp> make_shared();
3843
3844    template<class _A0>
3845        static shared_ptr<_Tp> make_shared(_A0&);
3846
3847    template<class _A0, class _A1>
3848        static shared_ptr<_Tp> make_shared(_A0&, _A1&);
3849
3850    template<class _A0, class _A1, class _A2>
3851        static shared_ptr<_Tp> make_shared(_A0&, _A1&, _A2&);
3852
3853    template<class _Alloc>
3854        static shared_ptr<_Tp>
3855        allocate_shared(const _Alloc& __a);
3856
3857    template<class _Alloc, class _A0>
3858        static shared_ptr<_Tp>
3859        allocate_shared(const _Alloc& __a, _A0& __a0);
3860
3861    template<class _Alloc, class _A0, class _A1>
3862        static shared_ptr<_Tp>
3863        allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1);
3864
3865    template<class _Alloc, class _A0, class _A1, class _A2>
3866        static shared_ptr<_Tp>
3867        allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2);
3868
3869#endif  // _LIBCPP_HAS_NO_VARIADICS
3870
3871private:
3872
3873    template <class _Yp, class _OrigPtr>
3874        _LIBCPP_INLINE_VISIBILITY
3875        void
3876        __enable_weak_this(const enable_shared_from_this<_Yp>* __e,
3877                           _OrigPtr* __ptr) _NOEXCEPT
3878        {
3879            typedef typename remove_cv<_Yp>::type _RawYp;
3880            if (__e && __e->__weak_this_.expired())
3881            {
3882                __e->__weak_this_ = shared_ptr<_RawYp>(*this,
3883                    const_cast<_RawYp*>(static_cast<const _Yp*>(__ptr)));
3884            }
3885        }
3886
3887    _LIBCPP_INLINE_VISIBILITY
3888    void __enable_weak_this(const volatile void*, const volatile void*) _NOEXCEPT {}
3889
3890    template <class _Up> friend class _LIBCPP_TEMPLATE_VIS shared_ptr;
3891    template <class _Up> friend class _LIBCPP_TEMPLATE_VIS weak_ptr;
3892};
3893
3894template<class _Tp>
3895inline
3896_LIBCPP_CONSTEXPR
3897shared_ptr<_Tp>::shared_ptr() _NOEXCEPT
3898    : __ptr_(0),
3899      __cntrl_(0)
3900{
3901}
3902
3903template<class _Tp>
3904inline
3905_LIBCPP_CONSTEXPR
3906shared_ptr<_Tp>::shared_ptr(nullptr_t) _NOEXCEPT
3907    : __ptr_(0),
3908      __cntrl_(0)
3909{
3910}
3911
3912template<class _Tp>
3913template<class _Yp>
3914shared_ptr<_Tp>::shared_ptr(_Yp* __p,
3915                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
3916    : __ptr_(__p)
3917{
3918    unique_ptr<_Yp> __hold(__p);
3919    typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk;
3920    __cntrl_ = new _CntrlBlk(__p, default_delete<_Yp>(), allocator<_Yp>());
3921    __hold.release();
3922    __enable_weak_this(__p, __p);
3923}
3924
3925template<class _Tp>
3926template<class _Yp, class _Dp>
3927shared_ptr<_Tp>::shared_ptr(_Yp* __p, _Dp __d,
3928                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
3929    : __ptr_(__p)
3930{
3931#ifndef _LIBCPP_NO_EXCEPTIONS
3932    try
3933    {
3934#endif  // _LIBCPP_NO_EXCEPTIONS
3935        typedef __shared_ptr_pointer<_Yp*, _Dp, allocator<_Yp> > _CntrlBlk;
3936        __cntrl_ = new _CntrlBlk(__p, __d, allocator<_Yp>());
3937        __enable_weak_this(__p, __p);
3938#ifndef _LIBCPP_NO_EXCEPTIONS
3939    }
3940    catch (...)
3941    {
3942        __d(__p);
3943        throw;
3944    }
3945#endif  // _LIBCPP_NO_EXCEPTIONS
3946}
3947
3948template<class _Tp>
3949template<class _Dp>
3950shared_ptr<_Tp>::shared_ptr(nullptr_t __p, _Dp __d)
3951    : __ptr_(0)
3952{
3953#ifndef _LIBCPP_NO_EXCEPTIONS
3954    try
3955    {
3956#endif  // _LIBCPP_NO_EXCEPTIONS
3957        typedef __shared_ptr_pointer<nullptr_t, _Dp, allocator<_Tp> > _CntrlBlk;
3958        __cntrl_ = new _CntrlBlk(__p, __d, allocator<_Tp>());
3959#ifndef _LIBCPP_NO_EXCEPTIONS
3960    }
3961    catch (...)
3962    {
3963        __d(__p);
3964        throw;
3965    }
3966#endif  // _LIBCPP_NO_EXCEPTIONS
3967}
3968
3969template<class _Tp>
3970template<class _Yp, class _Dp, class _Alloc>
3971shared_ptr<_Tp>::shared_ptr(_Yp* __p, _Dp __d, _Alloc __a,
3972                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
3973    : __ptr_(__p)
3974{
3975#ifndef _LIBCPP_NO_EXCEPTIONS
3976    try
3977    {
3978#endif  // _LIBCPP_NO_EXCEPTIONS
3979        typedef __shared_ptr_pointer<_Yp*, _Dp, _Alloc> _CntrlBlk;
3980        typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
3981        typedef __allocator_destructor<_A2> _D2;
3982        _A2 __a2(__a);
3983        unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
3984        ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
3985            _CntrlBlk(__p, __d, __a);
3986        __cntrl_ = _VSTD::addressof(*__hold2.release());
3987        __enable_weak_this(__p, __p);
3988#ifndef _LIBCPP_NO_EXCEPTIONS
3989    }
3990    catch (...)
3991    {
3992        __d(__p);
3993        throw;
3994    }
3995#endif  // _LIBCPP_NO_EXCEPTIONS
3996}
3997
3998template<class _Tp>
3999template<class _Dp, class _Alloc>
4000shared_ptr<_Tp>::shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a)
4001    : __ptr_(0)
4002{
4003#ifndef _LIBCPP_NO_EXCEPTIONS
4004    try
4005    {
4006#endif  // _LIBCPP_NO_EXCEPTIONS
4007        typedef __shared_ptr_pointer<nullptr_t, _Dp, _Alloc> _CntrlBlk;
4008        typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4009        typedef __allocator_destructor<_A2> _D2;
4010        _A2 __a2(__a);
4011        unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4012        ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4013            _CntrlBlk(__p, __d, __a);
4014        __cntrl_ = _VSTD::addressof(*__hold2.release());
4015#ifndef _LIBCPP_NO_EXCEPTIONS
4016    }
4017    catch (...)
4018    {
4019        __d(__p);
4020        throw;
4021    }
4022#endif  // _LIBCPP_NO_EXCEPTIONS
4023}
4024
4025template<class _Tp>
4026template<class _Yp>
4027inline
4028shared_ptr<_Tp>::shared_ptr(const shared_ptr<_Yp>& __r, element_type *__p) _NOEXCEPT
4029    : __ptr_(__p),
4030      __cntrl_(__r.__cntrl_)
4031{
4032    if (__cntrl_)
4033        __cntrl_->__add_shared();
4034}
4035
4036template<class _Tp>
4037inline
4038shared_ptr<_Tp>::shared_ptr(const shared_ptr& __r) _NOEXCEPT
4039    : __ptr_(__r.__ptr_),
4040      __cntrl_(__r.__cntrl_)
4041{
4042    if (__cntrl_)
4043        __cntrl_->__add_shared();
4044}
4045
4046template<class _Tp>
4047template<class _Yp>
4048inline
4049shared_ptr<_Tp>::shared_ptr(const shared_ptr<_Yp>& __r,
4050                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4051         _NOEXCEPT
4052    : __ptr_(__r.__ptr_),
4053      __cntrl_(__r.__cntrl_)
4054{
4055    if (__cntrl_)
4056        __cntrl_->__add_shared();
4057}
4058
4059#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4060
4061template<class _Tp>
4062inline
4063shared_ptr<_Tp>::shared_ptr(shared_ptr&& __r) _NOEXCEPT
4064    : __ptr_(__r.__ptr_),
4065      __cntrl_(__r.__cntrl_)
4066{
4067    __r.__ptr_ = 0;
4068    __r.__cntrl_ = 0;
4069}
4070
4071template<class _Tp>
4072template<class _Yp>
4073inline
4074shared_ptr<_Tp>::shared_ptr(shared_ptr<_Yp>&& __r,
4075                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4076         _NOEXCEPT
4077    : __ptr_(__r.__ptr_),
4078      __cntrl_(__r.__cntrl_)
4079{
4080    __r.__ptr_ = 0;
4081    __r.__cntrl_ = 0;
4082}
4083
4084#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4085
4086#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
4087template<class _Tp>
4088template<class _Yp>
4089#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4090shared_ptr<_Tp>::shared_ptr(auto_ptr<_Yp>&& __r,
4091#else
4092shared_ptr<_Tp>::shared_ptr(auto_ptr<_Yp> __r,
4093#endif
4094                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4095    : __ptr_(__r.get())
4096{
4097    typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk;
4098    __cntrl_ = new _CntrlBlk(__r.get(), default_delete<_Yp>(), allocator<_Yp>());
4099    __enable_weak_this(__r.get(), __r.get());
4100    __r.release();
4101}
4102#endif
4103
4104template<class _Tp>
4105template <class _Yp, class _Dp>
4106#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4107shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
4108#else
4109shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
4110#endif
4111                            typename enable_if
4112                            <
4113                                !is_lvalue_reference<_Dp>::value &&
4114                                !is_array<_Yp>::value &&
4115                                is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4116                                __nat
4117                            >::type)
4118    : __ptr_(__r.get())
4119{
4120#if _LIBCPP_STD_VER > 11
4121    if (__ptr_ == nullptr)
4122        __cntrl_ = nullptr;
4123    else
4124#endif
4125    {
4126        typedef __shared_ptr_pointer<_Yp*, _Dp, allocator<_Yp> > _CntrlBlk;
4127        __cntrl_ = new _CntrlBlk(__r.get(), __r.get_deleter(), allocator<_Yp>());
4128        __enable_weak_this(__r.get(), __r.get());
4129    }
4130    __r.release();
4131}
4132
4133template<class _Tp>
4134template <class _Yp, class _Dp>
4135#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4136shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
4137#else
4138shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
4139#endif
4140                            typename enable_if
4141                            <
4142                                is_lvalue_reference<_Dp>::value &&
4143                                !is_array<_Yp>::value &&
4144                                is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4145                                __nat
4146                            >::type)
4147    : __ptr_(__r.get())
4148{
4149#if _LIBCPP_STD_VER > 11
4150    if (__ptr_ == nullptr)
4151        __cntrl_ = nullptr;
4152    else
4153#endif
4154    {
4155        typedef __shared_ptr_pointer<_Yp*,
4156                                     reference_wrapper<typename remove_reference<_Dp>::type>,
4157                                     allocator<_Yp> > _CntrlBlk;
4158        __cntrl_ = new _CntrlBlk(__r.get(), ref(__r.get_deleter()), allocator<_Yp>());
4159        __enable_weak_this(__r.get(), __r.get());
4160    }
4161    __r.release();
4162}
4163
4164#ifndef _LIBCPP_HAS_NO_VARIADICS
4165
4166template<class _Tp>
4167template<class ..._Args>
4168shared_ptr<_Tp>
4169shared_ptr<_Tp>::make_shared(_Args&& ...__args)
4170{
4171    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4172    typedef allocator<_CntrlBlk> _A2;
4173    typedef __allocator_destructor<_A2> _D2;
4174    _A2 __a2;
4175    unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4176    ::new(__hold2.get()) _CntrlBlk(__a2, _VSTD::forward<_Args>(__args)...);
4177    shared_ptr<_Tp> __r;
4178    __r.__ptr_ = __hold2.get()->get();
4179    __r.__cntrl_ = __hold2.release();
4180    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4181    return __r;
4182}
4183
4184template<class _Tp>
4185template<class _Alloc, class ..._Args>
4186shared_ptr<_Tp>
4187shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _Args&& ...__args)
4188{
4189    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4190    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4191    typedef __allocator_destructor<_A2> _D2;
4192    _A2 __a2(__a);
4193    unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4194    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4195        _CntrlBlk(__a, _VSTD::forward<_Args>(__args)...);
4196    shared_ptr<_Tp> __r;
4197    __r.__ptr_ = __hold2.get()->get();
4198    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4199    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4200    return __r;
4201}
4202
4203#else  // _LIBCPP_HAS_NO_VARIADICS
4204
4205template<class _Tp>
4206shared_ptr<_Tp>
4207shared_ptr<_Tp>::make_shared()
4208{
4209    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4210    typedef allocator<_CntrlBlk> _Alloc2;
4211    typedef __allocator_destructor<_Alloc2> _D2;
4212    _Alloc2 __alloc2;
4213    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4214    ::new(__hold2.get()) _CntrlBlk(__alloc2);
4215    shared_ptr<_Tp> __r;
4216    __r.__ptr_ = __hold2.get()->get();
4217    __r.__cntrl_ = __hold2.release();
4218    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4219    return __r;
4220}
4221
4222template<class _Tp>
4223template<class _A0>
4224shared_ptr<_Tp>
4225shared_ptr<_Tp>::make_shared(_A0& __a0)
4226{
4227    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4228    typedef allocator<_CntrlBlk> _Alloc2;
4229    typedef __allocator_destructor<_Alloc2> _D2;
4230    _Alloc2 __alloc2;
4231    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4232    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0);
4233    shared_ptr<_Tp> __r;
4234    __r.__ptr_ = __hold2.get()->get();
4235    __r.__cntrl_ = __hold2.release();
4236    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4237    return __r;
4238}
4239
4240template<class _Tp>
4241template<class _A0, class _A1>
4242shared_ptr<_Tp>
4243shared_ptr<_Tp>::make_shared(_A0& __a0, _A1& __a1)
4244{
4245    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4246    typedef allocator<_CntrlBlk> _Alloc2;
4247    typedef __allocator_destructor<_Alloc2> _D2;
4248    _Alloc2 __alloc2;
4249    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4250    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0, __a1);
4251    shared_ptr<_Tp> __r;
4252    __r.__ptr_ = __hold2.get()->get();
4253    __r.__cntrl_ = __hold2.release();
4254    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4255    return __r;
4256}
4257
4258template<class _Tp>
4259template<class _A0, class _A1, class _A2>
4260shared_ptr<_Tp>
4261shared_ptr<_Tp>::make_shared(_A0& __a0, _A1& __a1, _A2& __a2)
4262{
4263    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4264    typedef allocator<_CntrlBlk> _Alloc2;
4265    typedef __allocator_destructor<_Alloc2> _D2;
4266    _Alloc2 __alloc2;
4267    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4268    ::new(__hold2.get()) _CntrlBlk(__alloc2, __a0, __a1, __a2);
4269    shared_ptr<_Tp> __r;
4270    __r.__ptr_ = __hold2.get()->get();
4271    __r.__cntrl_ = __hold2.release();
4272    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4273    return __r;
4274}
4275
4276template<class _Tp>
4277template<class _Alloc>
4278shared_ptr<_Tp>
4279shared_ptr<_Tp>::allocate_shared(const _Alloc& __a)
4280{
4281    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4282    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4283    typedef __allocator_destructor<_Alloc2> _D2;
4284    _Alloc2 __alloc2(__a);
4285    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4286    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4287        _CntrlBlk(__a);
4288    shared_ptr<_Tp> __r;
4289    __r.__ptr_ = __hold2.get()->get();
4290    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4291    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4292    return __r;
4293}
4294
4295template<class _Tp>
4296template<class _Alloc, class _A0>
4297shared_ptr<_Tp>
4298shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0)
4299{
4300    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4301    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4302    typedef __allocator_destructor<_Alloc2> _D2;
4303    _Alloc2 __alloc2(__a);
4304    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4305    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4306        _CntrlBlk(__a, __a0);
4307    shared_ptr<_Tp> __r;
4308    __r.__ptr_ = __hold2.get()->get();
4309    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4310    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4311    return __r;
4312}
4313
4314template<class _Tp>
4315template<class _Alloc, class _A0, class _A1>
4316shared_ptr<_Tp>
4317shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1)
4318{
4319    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4320    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4321    typedef __allocator_destructor<_Alloc2> _D2;
4322    _Alloc2 __alloc2(__a);
4323    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4324    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4325        _CntrlBlk(__a, __a0, __a1);
4326    shared_ptr<_Tp> __r;
4327    __r.__ptr_ = __hold2.get()->get();
4328    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4329    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4330    return __r;
4331}
4332
4333template<class _Tp>
4334template<class _Alloc, class _A0, class _A1, class _A2>
4335shared_ptr<_Tp>
4336shared_ptr<_Tp>::allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2)
4337{
4338    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4339    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _Alloc2;
4340    typedef __allocator_destructor<_Alloc2> _D2;
4341    _Alloc2 __alloc2(__a);
4342    unique_ptr<_CntrlBlk, _D2> __hold2(__alloc2.allocate(1), _D2(__alloc2, 1));
4343    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4344        _CntrlBlk(__a, __a0, __a1, __a2);
4345    shared_ptr<_Tp> __r;
4346    __r.__ptr_ = __hold2.get()->get();
4347    __r.__cntrl_ = _VSTD::addressof(*__hold2.release());
4348    __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
4349    return __r;
4350}
4351
4352#endif  // _LIBCPP_HAS_NO_VARIADICS
4353
4354template<class _Tp>
4355shared_ptr<_Tp>::~shared_ptr()
4356{
4357    if (__cntrl_)
4358        __cntrl_->__release_shared();
4359}
4360
4361template<class _Tp>
4362inline
4363shared_ptr<_Tp>&
4364shared_ptr<_Tp>::operator=(const shared_ptr& __r) _NOEXCEPT
4365{
4366    shared_ptr(__r).swap(*this);
4367    return *this;
4368}
4369
4370template<class _Tp>
4371template<class _Yp>
4372inline
4373typename enable_if
4374<
4375    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4376    shared_ptr<_Tp>&
4377>::type
4378shared_ptr<_Tp>::operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT
4379{
4380    shared_ptr(__r).swap(*this);
4381    return *this;
4382}
4383
4384#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4385
4386template<class _Tp>
4387inline
4388shared_ptr<_Tp>&
4389shared_ptr<_Tp>::operator=(shared_ptr&& __r) _NOEXCEPT
4390{
4391    shared_ptr(_VSTD::move(__r)).swap(*this);
4392    return *this;
4393}
4394
4395template<class _Tp>
4396template<class _Yp>
4397inline
4398typename enable_if
4399<
4400    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4401    shared_ptr<_Tp>&
4402>::type
4403shared_ptr<_Tp>::operator=(shared_ptr<_Yp>&& __r)
4404{
4405    shared_ptr(_VSTD::move(__r)).swap(*this);
4406    return *this;
4407}
4408
4409#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
4410template<class _Tp>
4411template<class _Yp>
4412inline
4413typename enable_if
4414<
4415    !is_array<_Yp>::value &&
4416    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4417    shared_ptr<_Tp>
4418>::type&
4419shared_ptr<_Tp>::operator=(auto_ptr<_Yp>&& __r)
4420{
4421    shared_ptr(_VSTD::move(__r)).swap(*this);
4422    return *this;
4423}
4424#endif
4425
4426template<class _Tp>
4427template <class _Yp, class _Dp>
4428inline
4429typename enable_if
4430<
4431    !is_array<_Yp>::value &&
4432    is_convertible<typename unique_ptr<_Yp, _Dp>::pointer,
4433                   typename shared_ptr<_Tp>::element_type*>::value,
4434    shared_ptr<_Tp>&
4435>::type
4436shared_ptr<_Tp>::operator=(unique_ptr<_Yp, _Dp>&& __r)
4437{
4438    shared_ptr(_VSTD::move(__r)).swap(*this);
4439    return *this;
4440}
4441
4442#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4443
4444#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
4445template<class _Tp>
4446template<class _Yp>
4447inline _LIBCPP_INLINE_VISIBILITY
4448typename enable_if
4449<
4450    !is_array<_Yp>::value &&
4451    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4452    shared_ptr<_Tp>&
4453>::type
4454shared_ptr<_Tp>::operator=(auto_ptr<_Yp> __r)
4455{
4456    shared_ptr(__r).swap(*this);
4457    return *this;
4458}
4459#endif
4460
4461template<class _Tp>
4462template <class _Yp, class _Dp>
4463inline _LIBCPP_INLINE_VISIBILITY
4464typename enable_if
4465<
4466    !is_array<_Yp>::value &&
4467    is_convertible<typename unique_ptr<_Yp, _Dp>::pointer,
4468                   typename shared_ptr<_Tp>::element_type*>::value,
4469    shared_ptr<_Tp>&
4470>::type
4471shared_ptr<_Tp>::operator=(unique_ptr<_Yp, _Dp> __r)
4472{
4473    shared_ptr(_VSTD::move(__r)).swap(*this);
4474    return *this;
4475}
4476
4477#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4478
4479template<class _Tp>
4480inline
4481void
4482shared_ptr<_Tp>::swap(shared_ptr& __r) _NOEXCEPT
4483{
4484    _VSTD::swap(__ptr_, __r.__ptr_);
4485    _VSTD::swap(__cntrl_, __r.__cntrl_);
4486}
4487
4488template<class _Tp>
4489inline
4490void
4491shared_ptr<_Tp>::reset() _NOEXCEPT
4492{
4493    shared_ptr().swap(*this);
4494}
4495
4496template<class _Tp>
4497template<class _Yp>
4498inline
4499typename enable_if
4500<
4501    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4502    void
4503>::type
4504shared_ptr<_Tp>::reset(_Yp* __p)
4505{
4506    shared_ptr(__p).swap(*this);
4507}
4508
4509template<class _Tp>
4510template<class _Yp, class _Dp>
4511inline
4512typename enable_if
4513<
4514    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4515    void
4516>::type
4517shared_ptr<_Tp>::reset(_Yp* __p, _Dp __d)
4518{
4519    shared_ptr(__p, __d).swap(*this);
4520}
4521
4522template<class _Tp>
4523template<class _Yp, class _Dp, class _Alloc>
4524inline
4525typename enable_if
4526<
4527    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4528    void
4529>::type
4530shared_ptr<_Tp>::reset(_Yp* __p, _Dp __d, _Alloc __a)
4531{
4532    shared_ptr(__p, __d, __a).swap(*this);
4533}
4534
4535#ifndef _LIBCPP_HAS_NO_VARIADICS
4536
4537template<class _Tp, class ..._Args>
4538inline _LIBCPP_INLINE_VISIBILITY
4539typename enable_if
4540<
4541    !is_array<_Tp>::value,
4542    shared_ptr<_Tp>
4543>::type
4544make_shared(_Args&& ...__args)
4545{
4546    return shared_ptr<_Tp>::make_shared(_VSTD::forward<_Args>(__args)...);
4547}
4548
4549template<class _Tp, class _Alloc, class ..._Args>
4550inline _LIBCPP_INLINE_VISIBILITY
4551typename enable_if
4552<
4553    !is_array<_Tp>::value,
4554    shared_ptr<_Tp>
4555>::type
4556allocate_shared(const _Alloc& __a, _Args&& ...__args)
4557{
4558    return shared_ptr<_Tp>::allocate_shared(__a, _VSTD::forward<_Args>(__args)...);
4559}
4560
4561#else  // _LIBCPP_HAS_NO_VARIADICS
4562
4563template<class _Tp>
4564inline _LIBCPP_INLINE_VISIBILITY
4565shared_ptr<_Tp>
4566make_shared()
4567{
4568    return shared_ptr<_Tp>::make_shared();
4569}
4570
4571template<class _Tp, class _A0>
4572inline _LIBCPP_INLINE_VISIBILITY
4573shared_ptr<_Tp>
4574make_shared(_A0& __a0)
4575{
4576    return shared_ptr<_Tp>::make_shared(__a0);
4577}
4578
4579template<class _Tp, class _A0, class _A1>
4580inline _LIBCPP_INLINE_VISIBILITY
4581shared_ptr<_Tp>
4582make_shared(_A0& __a0, _A1& __a1)
4583{
4584    return shared_ptr<_Tp>::make_shared(__a0, __a1);
4585}
4586
4587template<class _Tp, class _A0, class _A1, class _A2>
4588inline _LIBCPP_INLINE_VISIBILITY
4589shared_ptr<_Tp>
4590make_shared(_A0& __a0, _A1& __a1, _A2& __a2)
4591{
4592    return shared_ptr<_Tp>::make_shared(__a0, __a1, __a2);
4593}
4594
4595template<class _Tp, class _Alloc>
4596inline _LIBCPP_INLINE_VISIBILITY
4597shared_ptr<_Tp>
4598allocate_shared(const _Alloc& __a)
4599{
4600    return shared_ptr<_Tp>::allocate_shared(__a);
4601}
4602
4603template<class _Tp, class _Alloc, class _A0>
4604inline _LIBCPP_INLINE_VISIBILITY
4605shared_ptr<_Tp>
4606allocate_shared(const _Alloc& __a, _A0& __a0)
4607{
4608    return shared_ptr<_Tp>::allocate_shared(__a, __a0);
4609}
4610
4611template<class _Tp, class _Alloc, class _A0, class _A1>
4612inline _LIBCPP_INLINE_VISIBILITY
4613shared_ptr<_Tp>
4614allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1)
4615{
4616    return shared_ptr<_Tp>::allocate_shared(__a, __a0, __a1);
4617}
4618
4619template<class _Tp, class _Alloc, class _A0, class _A1, class _A2>
4620inline _LIBCPP_INLINE_VISIBILITY
4621shared_ptr<_Tp>
4622allocate_shared(const _Alloc& __a, _A0& __a0, _A1& __a1, _A2& __a2)
4623{
4624    return shared_ptr<_Tp>::allocate_shared(__a, __a0, __a1, __a2);
4625}
4626
4627#endif  // _LIBCPP_HAS_NO_VARIADICS
4628
4629template<class _Tp, class _Up>
4630inline _LIBCPP_INLINE_VISIBILITY
4631bool
4632operator==(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4633{
4634    return __x.get() == __y.get();
4635}
4636
4637template<class _Tp, class _Up>
4638inline _LIBCPP_INLINE_VISIBILITY
4639bool
4640operator!=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4641{
4642    return !(__x == __y);
4643}
4644
4645template<class _Tp, class _Up>
4646inline _LIBCPP_INLINE_VISIBILITY
4647bool
4648operator<(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4649{
4650    typedef typename common_type<_Tp*, _Up*>::type _Vp;
4651    return less<_Vp>()(__x.get(), __y.get());
4652}
4653
4654template<class _Tp, class _Up>
4655inline _LIBCPP_INLINE_VISIBILITY
4656bool
4657operator>(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4658{
4659    return __y < __x;
4660}
4661
4662template<class _Tp, class _Up>
4663inline _LIBCPP_INLINE_VISIBILITY
4664bool
4665operator<=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4666{
4667    return !(__y < __x);
4668}
4669
4670template<class _Tp, class _Up>
4671inline _LIBCPP_INLINE_VISIBILITY
4672bool
4673operator>=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4674{
4675    return !(__x < __y);
4676}
4677
4678template<class _Tp>
4679inline _LIBCPP_INLINE_VISIBILITY
4680bool
4681operator==(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4682{
4683    return !__x;
4684}
4685
4686template<class _Tp>
4687inline _LIBCPP_INLINE_VISIBILITY
4688bool
4689operator==(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4690{
4691    return !__x;
4692}
4693
4694template<class _Tp>
4695inline _LIBCPP_INLINE_VISIBILITY
4696bool
4697operator!=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4698{
4699    return static_cast<bool>(__x);
4700}
4701
4702template<class _Tp>
4703inline _LIBCPP_INLINE_VISIBILITY
4704bool
4705operator!=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4706{
4707    return static_cast<bool>(__x);
4708}
4709
4710template<class _Tp>
4711inline _LIBCPP_INLINE_VISIBILITY
4712bool
4713operator<(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4714{
4715    return less<_Tp*>()(__x.get(), nullptr);
4716}
4717
4718template<class _Tp>
4719inline _LIBCPP_INLINE_VISIBILITY
4720bool
4721operator<(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4722{
4723    return less<_Tp*>()(nullptr, __x.get());
4724}
4725
4726template<class _Tp>
4727inline _LIBCPP_INLINE_VISIBILITY
4728bool
4729operator>(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4730{
4731    return nullptr < __x;
4732}
4733
4734template<class _Tp>
4735inline _LIBCPP_INLINE_VISIBILITY
4736bool
4737operator>(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4738{
4739    return __x < nullptr;
4740}
4741
4742template<class _Tp>
4743inline _LIBCPP_INLINE_VISIBILITY
4744bool
4745operator<=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4746{
4747    return !(nullptr < __x);
4748}
4749
4750template<class _Tp>
4751inline _LIBCPP_INLINE_VISIBILITY
4752bool
4753operator<=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4754{
4755    return !(__x < nullptr);
4756}
4757
4758template<class _Tp>
4759inline _LIBCPP_INLINE_VISIBILITY
4760bool
4761operator>=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4762{
4763    return !(__x < nullptr);
4764}
4765
4766template<class _Tp>
4767inline _LIBCPP_INLINE_VISIBILITY
4768bool
4769operator>=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4770{
4771    return !(nullptr < __x);
4772}
4773
4774template<class _Tp>
4775inline _LIBCPP_INLINE_VISIBILITY
4776void
4777swap(shared_ptr<_Tp>& __x, shared_ptr<_Tp>& __y) _NOEXCEPT
4778{
4779    __x.swap(__y);
4780}
4781
4782template<class _Tp, class _Up>
4783inline _LIBCPP_INLINE_VISIBILITY
4784typename enable_if
4785<
4786    !is_array<_Tp>::value && !is_array<_Up>::value,
4787    shared_ptr<_Tp>
4788>::type
4789static_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
4790{
4791    return shared_ptr<_Tp>(__r, static_cast<_Tp*>(__r.get()));
4792}
4793
4794template<class _Tp, class _Up>
4795inline _LIBCPP_INLINE_VISIBILITY
4796typename enable_if
4797<
4798    !is_array<_Tp>::value && !is_array<_Up>::value,
4799    shared_ptr<_Tp>
4800>::type
4801dynamic_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
4802{
4803    _Tp* __p = dynamic_cast<_Tp*>(__r.get());
4804    return __p ? shared_ptr<_Tp>(__r, __p) : shared_ptr<_Tp>();
4805}
4806
4807template<class _Tp, class _Up>
4808typename enable_if
4809<
4810    is_array<_Tp>::value == is_array<_Up>::value,
4811    shared_ptr<_Tp>
4812>::type
4813const_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
4814{
4815    typedef typename remove_extent<_Tp>::type _RTp;
4816    return shared_ptr<_Tp>(__r, const_cast<_RTp*>(__r.get()));
4817}
4818
4819#ifndef _LIBCPP_NO_RTTI
4820
4821template<class _Dp, class _Tp>
4822inline _LIBCPP_INLINE_VISIBILITY
4823_Dp*
4824get_deleter(const shared_ptr<_Tp>& __p) _NOEXCEPT
4825{
4826    return __p.template __get_deleter<_Dp>();
4827}
4828
4829#endif  // _LIBCPP_NO_RTTI
4830
4831template<class _Tp>
4832class _LIBCPP_TEMPLATE_VIS weak_ptr
4833{
4834public:
4835    typedef _Tp element_type;
4836private:
4837    element_type*        __ptr_;
4838    __shared_weak_count* __cntrl_;
4839
4840public:
4841    _LIBCPP_INLINE_VISIBILITY
4842    _LIBCPP_CONSTEXPR weak_ptr() _NOEXCEPT;
4843    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(shared_ptr<_Yp> const& __r,
4844                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
4845                        _NOEXCEPT;
4846    _LIBCPP_INLINE_VISIBILITY
4847    weak_ptr(weak_ptr const& __r) _NOEXCEPT;
4848    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(weak_ptr<_Yp> const& __r,
4849                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
4850                         _NOEXCEPT;
4851
4852#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4853    _LIBCPP_INLINE_VISIBILITY
4854    weak_ptr(weak_ptr&& __r) _NOEXCEPT;
4855    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(weak_ptr<_Yp>&& __r,
4856                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
4857                         _NOEXCEPT;
4858#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4859    ~weak_ptr();
4860
4861    _LIBCPP_INLINE_VISIBILITY
4862    weak_ptr& operator=(weak_ptr const& __r) _NOEXCEPT;
4863    template<class _Yp>
4864        typename enable_if
4865        <
4866            is_convertible<_Yp*, element_type*>::value,
4867            weak_ptr&
4868        >::type
4869        _LIBCPP_INLINE_VISIBILITY
4870        operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT;
4871
4872#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4873
4874    _LIBCPP_INLINE_VISIBILITY
4875    weak_ptr& operator=(weak_ptr&& __r) _NOEXCEPT;
4876    template<class _Yp>
4877        typename enable_if
4878        <
4879            is_convertible<_Yp*, element_type*>::value,
4880            weak_ptr&
4881        >::type
4882        _LIBCPP_INLINE_VISIBILITY
4883        operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT;
4884
4885#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4886
4887    template<class _Yp>
4888        typename enable_if
4889        <
4890            is_convertible<_Yp*, element_type*>::value,
4891            weak_ptr&
4892        >::type
4893        _LIBCPP_INLINE_VISIBILITY
4894        operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT;
4895
4896    _LIBCPP_INLINE_VISIBILITY
4897    void swap(weak_ptr& __r) _NOEXCEPT;
4898    _LIBCPP_INLINE_VISIBILITY
4899    void reset() _NOEXCEPT;
4900
4901    _LIBCPP_INLINE_VISIBILITY
4902    long use_count() const _NOEXCEPT
4903        {return __cntrl_ ? __cntrl_->use_count() : 0;}
4904    _LIBCPP_INLINE_VISIBILITY
4905    bool expired() const _NOEXCEPT
4906        {return __cntrl_ == 0 || __cntrl_->use_count() == 0;}
4907    shared_ptr<_Tp> lock() const _NOEXCEPT;
4908    template<class _Up>
4909        _LIBCPP_INLINE_VISIBILITY
4910        bool owner_before(const shared_ptr<_Up>& __r) const
4911        {return __cntrl_ < __r.__cntrl_;}
4912    template<class _Up>
4913        _LIBCPP_INLINE_VISIBILITY
4914        bool owner_before(const weak_ptr<_Up>& __r) const
4915        {return __cntrl_ < __r.__cntrl_;}
4916
4917    template <class _Up> friend class _LIBCPP_TEMPLATE_VIS weak_ptr;
4918    template <class _Up> friend class _LIBCPP_TEMPLATE_VIS shared_ptr;
4919};
4920
4921template<class _Tp>
4922inline
4923_LIBCPP_CONSTEXPR
4924weak_ptr<_Tp>::weak_ptr() _NOEXCEPT
4925    : __ptr_(0),
4926      __cntrl_(0)
4927{
4928}
4929
4930template<class _Tp>
4931inline
4932weak_ptr<_Tp>::weak_ptr(weak_ptr const& __r) _NOEXCEPT
4933    : __ptr_(__r.__ptr_),
4934      __cntrl_(__r.__cntrl_)
4935{
4936    if (__cntrl_)
4937        __cntrl_->__add_weak();
4938}
4939
4940template<class _Tp>
4941template<class _Yp>
4942inline
4943weak_ptr<_Tp>::weak_ptr(shared_ptr<_Yp> const& __r,
4944                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
4945                         _NOEXCEPT
4946    : __ptr_(__r.__ptr_),
4947      __cntrl_(__r.__cntrl_)
4948{
4949    if (__cntrl_)
4950        __cntrl_->__add_weak();
4951}
4952
4953template<class _Tp>
4954template<class _Yp>
4955inline
4956weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp> const& __r,
4957                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
4958         _NOEXCEPT
4959    : __ptr_(__r.__ptr_),
4960      __cntrl_(__r.__cntrl_)
4961{
4962    if (__cntrl_)
4963        __cntrl_->__add_weak();
4964}
4965
4966#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4967
4968template<class _Tp>
4969inline
4970weak_ptr<_Tp>::weak_ptr(weak_ptr&& __r) _NOEXCEPT
4971    : __ptr_(__r.__ptr_),
4972      __cntrl_(__r.__cntrl_)
4973{
4974    __r.__ptr_ = 0;
4975    __r.__cntrl_ = 0;
4976}
4977
4978template<class _Tp>
4979template<class _Yp>
4980inline
4981weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp>&& __r,
4982                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
4983         _NOEXCEPT
4984    : __ptr_(__r.__ptr_),
4985      __cntrl_(__r.__cntrl_)
4986{
4987    __r.__ptr_ = 0;
4988    __r.__cntrl_ = 0;
4989}
4990
4991#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4992
4993template<class _Tp>
4994weak_ptr<_Tp>::~weak_ptr()
4995{
4996    if (__cntrl_)
4997        __cntrl_->__release_weak();
4998}
4999
5000template<class _Tp>
5001inline
5002weak_ptr<_Tp>&
5003weak_ptr<_Tp>::operator=(weak_ptr const& __r) _NOEXCEPT
5004{
5005    weak_ptr(__r).swap(*this);
5006    return *this;
5007}
5008
5009template<class _Tp>
5010template<class _Yp>
5011inline
5012typename enable_if
5013<
5014    is_convertible<_Yp*, _Tp*>::value,
5015    weak_ptr<_Tp>&
5016>::type
5017weak_ptr<_Tp>::operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT
5018{
5019    weak_ptr(__r).swap(*this);
5020    return *this;
5021}
5022
5023#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
5024
5025template<class _Tp>
5026inline
5027weak_ptr<_Tp>&
5028weak_ptr<_Tp>::operator=(weak_ptr&& __r) _NOEXCEPT
5029{
5030    weak_ptr(_VSTD::move(__r)).swap(*this);
5031    return *this;
5032}
5033
5034template<class _Tp>
5035template<class _Yp>
5036inline
5037typename enable_if
5038<
5039    is_convertible<_Yp*, _Tp*>::value,
5040    weak_ptr<_Tp>&
5041>::type
5042weak_ptr<_Tp>::operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT
5043{
5044    weak_ptr(_VSTD::move(__r)).swap(*this);
5045    return *this;
5046}
5047
5048#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
5049
5050template<class _Tp>
5051template<class _Yp>
5052inline
5053typename enable_if
5054<
5055    is_convertible<_Yp*, _Tp*>::value,
5056    weak_ptr<_Tp>&
5057>::type
5058weak_ptr<_Tp>::operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT
5059{
5060    weak_ptr(__r).swap(*this);
5061    return *this;
5062}
5063
5064template<class _Tp>
5065inline
5066void
5067weak_ptr<_Tp>::swap(weak_ptr& __r) _NOEXCEPT
5068{
5069    _VSTD::swap(__ptr_, __r.__ptr_);
5070    _VSTD::swap(__cntrl_, __r.__cntrl_);
5071}
5072
5073template<class _Tp>
5074inline _LIBCPP_INLINE_VISIBILITY
5075void
5076swap(weak_ptr<_Tp>& __x, weak_ptr<_Tp>& __y) _NOEXCEPT
5077{
5078    __x.swap(__y);
5079}
5080
5081template<class _Tp>
5082inline
5083void
5084weak_ptr<_Tp>::reset() _NOEXCEPT
5085{
5086    weak_ptr().swap(*this);
5087}
5088
5089template<class _Tp>
5090template<class _Yp>
5091shared_ptr<_Tp>::shared_ptr(const weak_ptr<_Yp>& __r,
5092                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
5093    : __ptr_(__r.__ptr_),
5094      __cntrl_(__r.__cntrl_ ? __r.__cntrl_->lock() : __r.__cntrl_)
5095{
5096    if (__cntrl_ == 0)
5097        __throw_bad_weak_ptr();
5098}
5099
5100template<class _Tp>
5101shared_ptr<_Tp>
5102weak_ptr<_Tp>::lock() const _NOEXCEPT
5103{
5104    shared_ptr<_Tp> __r;
5105    __r.__cntrl_ = __cntrl_ ? __cntrl_->lock() : __cntrl_;
5106    if (__r.__cntrl_)
5107        __r.__ptr_ = __ptr_;
5108    return __r;
5109}
5110
5111#if _LIBCPP_STD_VER > 14
5112template <class _Tp = void> struct owner_less;
5113#else
5114template <class _Tp> struct owner_less;
5115#endif
5116
5117template <class _Tp>
5118struct _LIBCPP_TEMPLATE_VIS owner_less<shared_ptr<_Tp> >
5119    : binary_function<shared_ptr<_Tp>, shared_ptr<_Tp>, bool>
5120{
5121    typedef bool result_type;
5122    _LIBCPP_INLINE_VISIBILITY
5123    bool operator()(shared_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const
5124        {return __x.owner_before(__y);}
5125    _LIBCPP_INLINE_VISIBILITY
5126    bool operator()(shared_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const
5127        {return __x.owner_before(__y);}
5128    _LIBCPP_INLINE_VISIBILITY
5129    bool operator()(  weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const
5130        {return __x.owner_before(__y);}
5131};
5132
5133template <class _Tp>
5134struct _LIBCPP_TEMPLATE_VIS owner_less<weak_ptr<_Tp> >
5135    : binary_function<weak_ptr<_Tp>, weak_ptr<_Tp>, bool>
5136{
5137    typedef bool result_type;
5138    _LIBCPP_INLINE_VISIBILITY
5139    bool operator()(  weak_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const
5140        {return __x.owner_before(__y);}
5141    _LIBCPP_INLINE_VISIBILITY
5142    bool operator()(shared_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const
5143        {return __x.owner_before(__y);}
5144    _LIBCPP_INLINE_VISIBILITY
5145    bool operator()(  weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const
5146        {return __x.owner_before(__y);}
5147};
5148
5149#if _LIBCPP_STD_VER > 14
5150template <>
5151struct _LIBCPP_TEMPLATE_VIS owner_less<void>
5152{
5153    template <class _Tp, class _Up>
5154    _LIBCPP_INLINE_VISIBILITY
5155    bool operator()( shared_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const
5156        {return __x.owner_before(__y);}
5157    template <class _Tp, class _Up>
5158    _LIBCPP_INLINE_VISIBILITY
5159    bool operator()( shared_ptr<_Tp> const& __x,  weak_ptr<_Up> const& __y) const
5160        {return __x.owner_before(__y);}
5161    template <class _Tp, class _Up>
5162    _LIBCPP_INLINE_VISIBILITY
5163    bool operator()(   weak_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const
5164        {return __x.owner_before(__y);}
5165    template <class _Tp, class _Up>
5166    _LIBCPP_INLINE_VISIBILITY
5167    bool operator()(   weak_ptr<_Tp> const& __x,   weak_ptr<_Up> const& __y) const
5168        {return __x.owner_before(__y);}
5169    typedef void is_transparent;
5170};
5171#endif
5172
5173template<class _Tp>
5174class _LIBCPP_TEMPLATE_VIS enable_shared_from_this
5175{
5176    mutable weak_ptr<_Tp> __weak_this_;
5177protected:
5178    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
5179    enable_shared_from_this() _NOEXCEPT {}
5180    _LIBCPP_INLINE_VISIBILITY
5181    enable_shared_from_this(enable_shared_from_this const&) _NOEXCEPT {}
5182    _LIBCPP_INLINE_VISIBILITY
5183    enable_shared_from_this& operator=(enable_shared_from_this const&) _NOEXCEPT
5184        {return *this;}
5185    _LIBCPP_INLINE_VISIBILITY
5186    ~enable_shared_from_this() {}
5187public:
5188    _LIBCPP_INLINE_VISIBILITY
5189    shared_ptr<_Tp> shared_from_this()
5190        {return shared_ptr<_Tp>(__weak_this_);}
5191    _LIBCPP_INLINE_VISIBILITY
5192    shared_ptr<_Tp const> shared_from_this() const
5193        {return shared_ptr<const _Tp>(__weak_this_);}
5194
5195#if _LIBCPP_STD_VER > 14
5196    _LIBCPP_INLINE_VISIBILITY
5197    weak_ptr<_Tp> weak_from_this() _NOEXCEPT
5198       { return __weak_this_; }
5199
5200    _LIBCPP_INLINE_VISIBILITY
5201    weak_ptr<const _Tp> weak_from_this() const _NOEXCEPT
5202        { return __weak_this_; }
5203#endif // _LIBCPP_STD_VER > 14
5204
5205    template <class _Up> friend class shared_ptr;
5206};
5207
5208template <class _Tp>
5209struct _LIBCPP_TEMPLATE_VIS hash<shared_ptr<_Tp> >
5210{
5211    typedef shared_ptr<_Tp>      argument_type;
5212    typedef size_t               result_type;
5213
5214    _LIBCPP_INLINE_VISIBILITY
5215    result_type operator()(const argument_type& __ptr) const _NOEXCEPT
5216    {
5217        return hash<_Tp*>()(__ptr.get());
5218    }
5219};
5220
5221template<class _CharT, class _Traits, class _Yp>
5222inline _LIBCPP_INLINE_VISIBILITY
5223basic_ostream<_CharT, _Traits>&
5224operator<<(basic_ostream<_CharT, _Traits>& __os, shared_ptr<_Yp> const& __p);
5225
5226
5227#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
5228
5229class _LIBCPP_TYPE_VIS __sp_mut
5230{
5231    void* __lx;
5232public:
5233    void lock() _NOEXCEPT;
5234    void unlock() _NOEXCEPT;
5235
5236private:
5237    _LIBCPP_CONSTEXPR __sp_mut(void*) _NOEXCEPT;
5238    __sp_mut(const __sp_mut&);
5239    __sp_mut& operator=(const __sp_mut&);
5240
5241    friend _LIBCPP_FUNC_VIS __sp_mut& __get_sp_mut(const void*);
5242};
5243
5244_LIBCPP_FUNC_VIS __sp_mut& __get_sp_mut(const void*);
5245
5246template <class _Tp>
5247inline _LIBCPP_INLINE_VISIBILITY
5248bool
5249atomic_is_lock_free(const shared_ptr<_Tp>*)
5250{
5251    return false;
5252}
5253
5254template <class _Tp>
5255shared_ptr<_Tp>
5256atomic_load(const shared_ptr<_Tp>* __p)
5257{
5258    __sp_mut& __m = __get_sp_mut(__p);
5259    __m.lock();
5260    shared_ptr<_Tp> __q = *__p;
5261    __m.unlock();
5262    return __q;
5263}
5264
5265template <class _Tp>
5266inline _LIBCPP_INLINE_VISIBILITY
5267shared_ptr<_Tp>
5268atomic_load_explicit(const shared_ptr<_Tp>* __p, memory_order)
5269{
5270    return atomic_load(__p);
5271}
5272
5273template <class _Tp>
5274void
5275atomic_store(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
5276{
5277    __sp_mut& __m = __get_sp_mut(__p);
5278    __m.lock();
5279    __p->swap(__r);
5280    __m.unlock();
5281}
5282
5283template <class _Tp>
5284inline _LIBCPP_INLINE_VISIBILITY
5285void
5286atomic_store_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
5287{
5288    atomic_store(__p, __r);
5289}
5290
5291template <class _Tp>
5292shared_ptr<_Tp>
5293atomic_exchange(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
5294{
5295    __sp_mut& __m = __get_sp_mut(__p);
5296    __m.lock();
5297    __p->swap(__r);
5298    __m.unlock();
5299    return __r;
5300}
5301
5302template <class _Tp>
5303inline _LIBCPP_INLINE_VISIBILITY
5304shared_ptr<_Tp>
5305atomic_exchange_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
5306{
5307    return atomic_exchange(__p, __r);
5308}
5309
5310template <class _Tp>
5311bool
5312atomic_compare_exchange_strong(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
5313{
5314    shared_ptr<_Tp> __temp;
5315    __sp_mut& __m = __get_sp_mut(__p);
5316    __m.lock();
5317    if (__p->__owner_equivalent(*__v))
5318    {
5319        _VSTD::swap(__temp, *__p);
5320        *__p = __w;
5321        __m.unlock();
5322        return true;
5323    }
5324    _VSTD::swap(__temp, *__v);
5325    *__v = *__p;
5326    __m.unlock();
5327    return false;
5328}
5329
5330template <class _Tp>
5331inline _LIBCPP_INLINE_VISIBILITY
5332bool
5333atomic_compare_exchange_weak(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
5334{
5335    return atomic_compare_exchange_strong(__p, __v, __w);
5336}
5337
5338template <class _Tp>
5339inline _LIBCPP_INLINE_VISIBILITY
5340bool
5341atomic_compare_exchange_strong_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
5342                                        shared_ptr<_Tp> __w, memory_order, memory_order)
5343{
5344    return atomic_compare_exchange_strong(__p, __v, __w);
5345}
5346
5347template <class _Tp>
5348inline _LIBCPP_INLINE_VISIBILITY
5349bool
5350atomic_compare_exchange_weak_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
5351                                      shared_ptr<_Tp> __w, memory_order, memory_order)
5352{
5353    return atomic_compare_exchange_weak(__p, __v, __w);
5354}
5355
5356#endif  // !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
5357
5358//enum class
5359#if defined(_LIBCPP_ABI_POINTER_SAFETY_ENUM_TYPE)
5360# ifndef _LIBCPP_CXX03_LANG
5361enum class pointer_safety : unsigned char {
5362  relaxed,
5363  preferred,
5364  strict
5365};
5366# endif
5367#else
5368struct _LIBCPP_TYPE_VIS pointer_safety
5369{
5370    enum __lx
5371    {
5372        relaxed,
5373        preferred,
5374        strict
5375    };
5376
5377    __lx __v_;
5378
5379    _LIBCPP_INLINE_VISIBILITY
5380    pointer_safety() : __v_() {}
5381
5382    _LIBCPP_INLINE_VISIBILITY
5383    pointer_safety(__lx __v) : __v_(__v) {}
5384    _LIBCPP_INLINE_VISIBILITY
5385    operator int() const {return __v_;}
5386};
5387#endif
5388
5389#if !defined(_LIBCPP_ABI_POINTER_SAFETY_ENUM_TYPE) && \
5390    defined(_LIBCPP_BUILDING_MEMORY)
5391_LIBCPP_FUNC_VIS pointer_safety get_pointer_safety() _NOEXCEPT;
5392#else
5393// This function is only offered in C++03 under ABI v1.
5394# if !defined(_LIBCPP_ABI_POINTER_SAFETY_ENUM_TYPE) || !defined(_LIBCPP_CXX03_LANG)
5395inline _LIBCPP_INLINE_VISIBILITY
5396pointer_safety get_pointer_safety() _NOEXCEPT {
5397  return pointer_safety::relaxed;
5398}
5399# endif
5400#endif
5401
5402
5403_LIBCPP_FUNC_VIS void declare_reachable(void* __p);
5404_LIBCPP_FUNC_VIS void declare_no_pointers(char* __p, size_t __n);
5405_LIBCPP_FUNC_VIS void undeclare_no_pointers(char* __p, size_t __n);
5406_LIBCPP_FUNC_VIS void* __undeclare_reachable(void* __p);
5407
5408template <class _Tp>
5409inline _LIBCPP_INLINE_VISIBILITY
5410_Tp*
5411undeclare_reachable(_Tp* __p)
5412{
5413    return static_cast<_Tp*>(__undeclare_reachable(__p));
5414}
5415
5416_LIBCPP_FUNC_VIS void* align(size_t __align, size_t __sz, void*& __ptr, size_t& __space);
5417
5418// --- Helper for container swap --
5419template <typename _Alloc>
5420inline _LIBCPP_INLINE_VISIBILITY
5421void __swap_allocator(_Alloc & __a1, _Alloc & __a2)
5422#if _LIBCPP_STD_VER >= 14
5423    _NOEXCEPT
5424#else
5425    _NOEXCEPT_(__is_nothrow_swappable<_Alloc>::value)
5426#endif
5427{
5428    __swap_allocator(__a1, __a2,
5429      integral_constant<bool, _VSTD::allocator_traits<_Alloc>::propagate_on_container_swap::value>());
5430}
5431
5432template <typename _Alloc>
5433_LIBCPP_INLINE_VISIBILITY
5434void __swap_allocator(_Alloc & __a1, _Alloc & __a2, true_type)
5435#if _LIBCPP_STD_VER >= 14
5436    _NOEXCEPT
5437#else
5438    _NOEXCEPT_(__is_nothrow_swappable<_Alloc>::value)
5439#endif
5440{
5441    using _VSTD::swap;
5442    swap(__a1, __a2);
5443}
5444
5445template <typename _Alloc>
5446inline _LIBCPP_INLINE_VISIBILITY
5447void __swap_allocator(_Alloc &, _Alloc &, false_type) _NOEXCEPT {}
5448
5449template <typename _Alloc, typename _Traits=allocator_traits<_Alloc> >
5450struct __noexcept_move_assign_container : public integral_constant<bool,
5451    _Traits::propagate_on_container_move_assignment::value
5452#if _LIBCPP_STD_VER > 14
5453        || _Traits::is_always_equal::value
5454#else
5455        && is_nothrow_move_assignable<_Alloc>::value
5456#endif
5457    > {};
5458
5459
5460#ifndef _LIBCPP_HAS_NO_VARIADICS
5461template <class _Tp, class _Alloc>
5462struct __temp_value {
5463    typedef allocator_traits<_Alloc> _Traits;
5464
5465    typename aligned_storage<sizeof(_Tp), alignof(_Tp)>::type __v;
5466    _Alloc &__a;
5467
5468    _Tp *__addr() { return reinterpret_cast<_Tp *>(addressof(__v)); }
5469    _Tp &   get() { return *__addr(); }
5470
5471    template<class... _Args>
5472    __temp_value(_Alloc &__alloc, _Args&& ... __args) : __a(__alloc)
5473    { _Traits::construct(__a, __addr(), _VSTD::forward<_Args>(__args)...); }
5474
5475    ~__temp_value() { _Traits::destroy(__a, __addr()); }
5476    };
5477#endif
5478
5479_LIBCPP_END_NAMESPACE_STD
5480
5481#endif  // _LIBCPP_MEMORY
5482