xref: /llvm-project-15.0.7/libcxx/include/memory (revision 8e63f35f)
1// -*- C++ -*-
2//===-------------------------- memory ------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_MEMORY
11#define _LIBCPP_MEMORY
12
13/*
14    memory synopsis
15
16namespace std
17{
18
19struct allocator_arg_t { };
20inline constexpr allocator_arg_t allocator_arg = allocator_arg_t();
21
22template <class T, class Alloc> struct uses_allocator;
23
24template <class Ptr>
25struct pointer_traits
26{
27    typedef Ptr pointer;
28    typedef <details> element_type;
29    typedef <details> difference_type;
30
31    template <class U> using rebind = <details>;
32
33    static pointer pointer_to(<details>);
34};
35
36template <class T>
37struct pointer_traits<T*>
38{
39    typedef T* pointer;
40    typedef T element_type;
41    typedef ptrdiff_t difference_type;
42
43    template <class U> using rebind = U*;
44
45    static pointer pointer_to(<details>) noexcept; // constexpr in C++20
46};
47
48template <class T> constexpr T* to_address(T* p) noexcept; // C++20
49template <class Ptr> auto to_address(const Ptr& p) noexcept; // C++20
50
51template <class Alloc>
52struct allocator_traits
53{
54    typedef Alloc                        allocator_type;
55    typedef typename allocator_type::value_type
56                                         value_type;
57
58    typedef Alloc::pointer | value_type* pointer;
59    typedef Alloc::const_pointer
60          | pointer_traits<pointer>::rebind<const value_type>
61                                         const_pointer;
62    typedef Alloc::void_pointer
63          | pointer_traits<pointer>::rebind<void>
64                                         void_pointer;
65    typedef Alloc::const_void_pointer
66          | pointer_traits<pointer>::rebind<const void>
67                                         const_void_pointer;
68    typedef Alloc::difference_type
69          | pointer_traits<pointer>::difference_type
70                                         difference_type;
71    typedef Alloc::size_type
72          | make_unsigned<difference_type>::type
73                                         size_type;
74    typedef Alloc::propagate_on_container_copy_assignment
75          | false_type                   propagate_on_container_copy_assignment;
76    typedef Alloc::propagate_on_container_move_assignment
77          | false_type                   propagate_on_container_move_assignment;
78    typedef Alloc::propagate_on_container_swap
79          | false_type                   propagate_on_container_swap;
80    typedef Alloc::is_always_equal
81          | is_empty                     is_always_equal;
82
83    template <class T> using rebind_alloc  = Alloc::rebind<T>::other | Alloc<T, Args...>;
84    template <class T> using rebind_traits = allocator_traits<rebind_alloc<T>>;
85
86    static pointer allocate(allocator_type& a, size_type n);                          // [[nodiscard]] in C++20
87    static pointer allocate(allocator_type& a, size_type n, const_void_pointer hint); // [[nodiscard]] in C++20
88
89    static void deallocate(allocator_type& a, pointer p, size_type n) noexcept;
90
91    template <class T, class... Args>
92        static void construct(allocator_type& a, T* p, Args&&... args);
93
94    template <class T>
95        static void destroy(allocator_type& a, T* p);
96
97    static size_type max_size(const allocator_type& a); // noexcept in C++14
98
99    static allocator_type
100        select_on_container_copy_construction(const allocator_type& a);
101};
102
103template <>
104class allocator<void> // deprecated in C++17, removed in C++20
105{
106public:
107    typedef void*                                 pointer;
108    typedef const void*                           const_pointer;
109    typedef void                                  value_type;
110
111    template <class _Up> struct rebind {typedef allocator<_Up> other;};
112};
113
114template <class T>
115class allocator
116{
117public:
118    typedef size_t    size_type;                         // deprecated in C++17, removed in C++20
119    typedef ptrdiff_t difference_type;                   // deprecated in C++17, removed in C++20
120    typedef T*        pointer;                           // deprecated in C++17, removed in C++20
121    typedef const T*  const_pointer;                     // deprecated in C++17, removed in C++20
122    typedef typename add_lvalue_reference<T>::type
123                      reference;                         // deprecated in C++17, removed in C++20
124    typedef typename add_lvalue_reference<const T>::type
125                      const_reference;                   // deprecated in C++17, removed in C++20
126
127    typedef T         value_type;
128
129    template <class U> struct rebind {typedef allocator<U> other;}; // deprecated in C++17, removed in C++20
130
131    typedef true_type propagate_on_container_move_assignment;
132    typedef true_type is_always_equal;
133
134    constexpr allocator() noexcept;                      // constexpr in C++20
135    constexpr allocator(const allocator&) noexcept;      // constexpr in C++20
136    template <class U>
137      constexpr allocator(const allocator<U>&) noexcept; // constexpr in C++20
138    ~allocator();
139    pointer address(reference x) const noexcept;             // deprecated in C++17, removed in C++20
140    const_pointer address(const_reference x) const noexcept; // deprecated in C++17, removed in C++20
141    T* allocate(size_t n, const void* hint);          // deprecated in C++17, removed in C++20
142    T* allocate(size_t n);
143    void deallocate(T* p, size_t n) noexcept;
144    size_type max_size() const noexcept;              // deprecated in C++17, removed in C++20
145    template<class U, class... Args>
146        void construct(U* p, Args&&... args);         // deprecated in C++17, removed in C++20
147    template <class U>
148        void destroy(U* p);                           // deprecated in C++17, removed in C++20
149};
150
151template <class T, class U>
152bool operator==(const allocator<T>&, const allocator<U>&) noexcept;
153
154template <class T, class U>
155bool operator!=(const allocator<T>&, const allocator<U>&) noexcept;
156
157template <class OutputIterator, class T>
158class raw_storage_iterator
159    : public iterator<output_iterator_tag,
160                      T,                               // purposefully not C++03
161                      ptrdiff_t,                       // purposefully not C++03
162                      T*,                              // purposefully not C++03
163                      raw_storage_iterator&>           // purposefully not C++03
164{
165public:
166    explicit raw_storage_iterator(OutputIterator x);
167    raw_storage_iterator& operator*();
168    raw_storage_iterator& operator=(const T& element);
169    raw_storage_iterator& operator++();
170    raw_storage_iterator  operator++(int);
171};
172
173template <class T> pair<T*,ptrdiff_t> get_temporary_buffer(ptrdiff_t n) noexcept;
174template <class T> void               return_temporary_buffer(T* p) noexcept;
175
176template <class T> T* addressof(T& r) noexcept;
177template <class T> T* addressof(const T&& r) noexcept = delete;
178
179template <class InputIterator, class ForwardIterator>
180ForwardIterator
181uninitialized_copy(InputIterator first, InputIterator last, ForwardIterator result);
182
183template <class InputIterator, class Size, class ForwardIterator>
184ForwardIterator
185uninitialized_copy_n(InputIterator first, Size n, ForwardIterator result);
186
187template <class ForwardIterator, class T>
188void uninitialized_fill(ForwardIterator first, ForwardIterator last, const T& x);
189
190template <class ForwardIterator, class Size, class T>
191ForwardIterator
192uninitialized_fill_n(ForwardIterator first, Size n, const T& x);
193
194template <class T>
195void destroy_at(T* location);
196
197template <class ForwardIterator>
198 void destroy(ForwardIterator first, ForwardIterator last);
199
200template <class ForwardIterator, class Size>
201 ForwardIterator destroy_n(ForwardIterator first, Size n);
202
203template <class InputIterator, class ForwardIterator>
204 ForwardIterator uninitialized_move(InputIterator first, InputIterator last, ForwardIterator result);
205
206template <class InputIterator, class Size, class ForwardIterator>
207 pair<InputIterator,ForwardIterator> uninitialized_move_n(InputIterator first, Size n, ForwardIterator result);
208
209template <class ForwardIterator>
210 void uninitialized_value_construct(ForwardIterator first, ForwardIterator last);
211
212template <class ForwardIterator, class Size>
213 ForwardIterator uninitialized_value_construct_n(ForwardIterator first, Size n);
214
215template <class ForwardIterator>
216 void uninitialized_default_construct(ForwardIterator first, ForwardIterator last);
217
218template <class ForwardIterator, class Size>
219 ForwardIterator uninitialized_default_construct_n(ForwardIterator first, Size n);
220
221template <class Y> struct auto_ptr_ref {};      // deprecated in C++11, removed in C++17
222
223template<class X>
224class auto_ptr                                  // deprecated in C++11, removed in C++17
225{
226public:
227    typedef X element_type;
228
229    explicit auto_ptr(X* p =0) throw();
230    auto_ptr(auto_ptr&) throw();
231    template<class Y> auto_ptr(auto_ptr<Y>&) throw();
232    auto_ptr& operator=(auto_ptr&) throw();
233    template<class Y> auto_ptr& operator=(auto_ptr<Y>&) throw();
234    auto_ptr& operator=(auto_ptr_ref<X> r) throw();
235    ~auto_ptr() throw();
236
237    typename add_lvalue_reference<X>::type operator*() const throw();
238    X* operator->() const throw();
239    X* get() const throw();
240    X* release() throw();
241    void reset(X* p =0) throw();
242
243    auto_ptr(auto_ptr_ref<X>) throw();
244    template<class Y> operator auto_ptr_ref<Y>() throw();
245    template<class Y> operator auto_ptr<Y>() throw();
246};
247
248template <class T>
249struct default_delete
250{
251    constexpr default_delete() noexcept = default;
252    template <class U> default_delete(const default_delete<U>&) noexcept;
253
254    void operator()(T*) const noexcept;
255};
256
257template <class T>
258struct default_delete<T[]>
259{
260    constexpr default_delete() noexcept = default;
261    void operator()(T*) const noexcept;
262    template <class U> void operator()(U*) const = delete;
263};
264
265template <class T, class D = default_delete<T>>
266class unique_ptr
267{
268public:
269    typedef see below pointer;
270    typedef T element_type;
271    typedef D deleter_type;
272
273    // constructors
274    constexpr unique_ptr() noexcept;
275    explicit unique_ptr(pointer p) noexcept;
276    unique_ptr(pointer p, see below d1) noexcept;
277    unique_ptr(pointer p, see below d2) noexcept;
278    unique_ptr(unique_ptr&& u) noexcept;
279    unique_ptr(nullptr_t) noexcept : unique_ptr() { }
280    template <class U, class E>
281        unique_ptr(unique_ptr<U, E>&& u) noexcept;
282    template <class U>
283        unique_ptr(auto_ptr<U>&& u) noexcept;       // removed in C++17
284
285    // destructor
286    ~unique_ptr();
287
288    // assignment
289    unique_ptr& operator=(unique_ptr&& u) noexcept;
290    template <class U, class E> unique_ptr& operator=(unique_ptr<U, E>&& u) noexcept;
291    unique_ptr& operator=(nullptr_t) noexcept;
292
293    // observers
294    typename add_lvalue_reference<T>::type operator*() const;
295    pointer operator->() const noexcept;
296    pointer get() const noexcept;
297    deleter_type& get_deleter() noexcept;
298    const deleter_type& get_deleter() const noexcept;
299    explicit operator bool() const noexcept;
300
301    // modifiers
302    pointer release() noexcept;
303    void reset(pointer p = pointer()) noexcept;
304    void swap(unique_ptr& u) noexcept;
305};
306
307template <class T, class D>
308class unique_ptr<T[], D>
309{
310public:
311    typedef implementation-defined pointer;
312    typedef T element_type;
313    typedef D deleter_type;
314
315    // constructors
316    constexpr unique_ptr() noexcept;
317    explicit unique_ptr(pointer p) noexcept;
318    unique_ptr(pointer p, see below d) noexcept;
319    unique_ptr(pointer p, see below d) noexcept;
320    unique_ptr(unique_ptr&& u) noexcept;
321    unique_ptr(nullptr_t) noexcept : unique_ptr() { }
322
323    // destructor
324    ~unique_ptr();
325
326    // assignment
327    unique_ptr& operator=(unique_ptr&& u) noexcept;
328    unique_ptr& operator=(nullptr_t) noexcept;
329
330    // observers
331    T& operator[](size_t i) const;
332    pointer get() const noexcept;
333    deleter_type& get_deleter() noexcept;
334    const deleter_type& get_deleter() const noexcept;
335    explicit operator bool() const noexcept;
336
337    // modifiers
338    pointer release() noexcept;
339    void reset(pointer p = pointer()) noexcept;
340    void reset(nullptr_t) noexcept;
341    template <class U> void reset(U) = delete;
342    void swap(unique_ptr& u) noexcept;
343};
344
345template <class T, class D>
346    void swap(unique_ptr<T, D>& x, unique_ptr<T, D>& y) noexcept;
347
348template <class T1, class D1, class T2, class D2>
349    bool operator==(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
350template <class T1, class D1, class T2, class D2>
351    bool operator!=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
352template <class T1, class D1, class T2, class D2>
353    bool operator<(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
354template <class T1, class D1, class T2, class D2>
355    bool operator<=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
356template <class T1, class D1, class T2, class D2>
357    bool operator>(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
358template <class T1, class D1, class T2, class D2>
359    bool operator>=(const unique_ptr<T1, D1>& x, const unique_ptr<T2, D2>& y);
360
361template <class T, class D>
362    bool operator==(const unique_ptr<T, D>& x, nullptr_t) noexcept;
363template <class T, class D>
364    bool operator==(nullptr_t, const unique_ptr<T, D>& y) noexcept;
365template <class T, class D>
366    bool operator!=(const unique_ptr<T, D>& x, nullptr_t) noexcept;
367template <class T, class D>
368    bool operator!=(nullptr_t, const unique_ptr<T, D>& y) noexcept;
369
370template <class T, class D>
371    bool operator<(const unique_ptr<T, D>& x, nullptr_t);
372template <class T, class D>
373    bool operator<(nullptr_t, const unique_ptr<T, D>& y);
374template <class T, class D>
375    bool operator<=(const unique_ptr<T, D>& x, nullptr_t);
376template <class T, class D>
377    bool operator<=(nullptr_t, const unique_ptr<T, D>& y);
378template <class T, class D>
379    bool operator>(const unique_ptr<T, D>& x, nullptr_t);
380template <class T, class D>
381    bool operator>(nullptr_t, const unique_ptr<T, D>& y);
382template <class T, class D>
383    bool operator>=(const unique_ptr<T, D>& x, nullptr_t);
384template <class T, class D>
385    bool operator>=(nullptr_t, const unique_ptr<T, D>& y);
386
387class bad_weak_ptr
388    : public std::exception
389{
390    bad_weak_ptr() noexcept;
391};
392
393template<class T, class... Args> unique_ptr<T> make_unique(Args&&... args);     // C++14
394template<class T>                unique_ptr<T> make_unique(size_t n);           // C++14
395template<class T, class... Args> unspecified   make_unique(Args&&...) = delete; // C++14, T == U[N]
396
397template<class E, class T, class Y, class D>
398    basic_ostream<E, T>& operator<< (basic_ostream<E, T>& os, unique_ptr<Y, D> const& p);
399
400template<class T>
401class shared_ptr
402{
403public:
404    typedef T element_type;
405    typedef weak_ptr<T> weak_type; // C++17
406
407    // constructors:
408    constexpr shared_ptr() noexcept;
409    template<class Y> explicit shared_ptr(Y* p);
410    template<class Y, class D> shared_ptr(Y* p, D d);
411    template<class Y, class D, class A> shared_ptr(Y* p, D d, A a);
412    template <class D> shared_ptr(nullptr_t p, D d);
413    template <class D, class A> shared_ptr(nullptr_t p, D d, A a);
414    template<class Y> shared_ptr(const shared_ptr<Y>& r, T *p) noexcept;
415    shared_ptr(const shared_ptr& r) noexcept;
416    template<class Y> shared_ptr(const shared_ptr<Y>& r) noexcept;
417    shared_ptr(shared_ptr&& r) noexcept;
418    template<class Y> shared_ptr(shared_ptr<Y>&& r) noexcept;
419    template<class Y> explicit shared_ptr(const weak_ptr<Y>& r);
420    template<class Y> shared_ptr(auto_ptr<Y>&& r);          // removed in C++17
421    template <class Y, class D> shared_ptr(unique_ptr<Y, D>&& r);
422    shared_ptr(nullptr_t) : shared_ptr() { }
423
424    // destructor:
425    ~shared_ptr();
426
427    // assignment:
428    shared_ptr& operator=(const shared_ptr& r) noexcept;
429    template<class Y> shared_ptr& operator=(const shared_ptr<Y>& r) noexcept;
430    shared_ptr& operator=(shared_ptr&& r) noexcept;
431    template<class Y> shared_ptr& operator=(shared_ptr<Y>&& r);
432    template<class Y> shared_ptr& operator=(auto_ptr<Y>&& r); // removed in C++17
433    template <class Y, class D> shared_ptr& operator=(unique_ptr<Y, D>&& r);
434
435    // modifiers:
436    void swap(shared_ptr& r) noexcept;
437    void reset() noexcept;
438    template<class Y> void reset(Y* p);
439    template<class Y, class D> void reset(Y* p, D d);
440    template<class Y, class D, class A> void reset(Y* p, D d, A a);
441
442    // observers:
443    T* get() const noexcept;
444    T& operator*() const noexcept;
445    T* operator->() const noexcept;
446    long use_count() const noexcept;
447    bool unique() const noexcept;
448    explicit operator bool() const noexcept;
449    template<class U> bool owner_before(shared_ptr<U> const& b) const noexcept;
450    template<class U> bool owner_before(weak_ptr<U> const& b) const noexcept;
451};
452
453template<class T>
454shared_ptr(weak_ptr<T>) -> shared_ptr<T>;
455template<class T, class D>
456shared_ptr(unique_ptr<T, D>) -> shared_ptr<T>;
457
458// shared_ptr comparisons:
459template<class T, class U>
460    bool operator==(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
461template<class T, class U>
462    bool operator!=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
463template<class T, class U>
464    bool operator<(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
465template<class T, class U>
466    bool operator>(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
467template<class T, class U>
468    bool operator<=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
469template<class T, class U>
470    bool operator>=(shared_ptr<T> const& a, shared_ptr<U> const& b) noexcept;
471
472template <class T>
473    bool operator==(const shared_ptr<T>& x, nullptr_t) noexcept;
474template <class T>
475    bool operator==(nullptr_t, const shared_ptr<T>& y) noexcept;
476template <class T>
477    bool operator!=(const shared_ptr<T>& x, nullptr_t) noexcept;
478template <class T>
479    bool operator!=(nullptr_t, const shared_ptr<T>& y) noexcept;
480template <class T>
481    bool operator<(const shared_ptr<T>& x, nullptr_t) noexcept;
482template <class T>
483bool operator<(nullptr_t, const shared_ptr<T>& y) noexcept;
484template <class T>
485    bool operator<=(const shared_ptr<T>& x, nullptr_t) noexcept;
486template <class T>
487    bool operator<=(nullptr_t, const shared_ptr<T>& y) noexcept;
488template <class T>
489    bool operator>(const shared_ptr<T>& x, nullptr_t) noexcept;
490template <class T>
491    bool operator>(nullptr_t, const shared_ptr<T>& y) noexcept;
492template <class T>
493    bool operator>=(const shared_ptr<T>& x, nullptr_t) noexcept;
494template <class T>
495    bool operator>=(nullptr_t, const shared_ptr<T>& y) noexcept;
496
497// shared_ptr specialized algorithms:
498template<class T> void swap(shared_ptr<T>& a, shared_ptr<T>& b) noexcept;
499
500// shared_ptr casts:
501template<class T, class U>
502    shared_ptr<T> static_pointer_cast(shared_ptr<U> const& r) noexcept;
503template<class T, class U>
504    shared_ptr<T> dynamic_pointer_cast(shared_ptr<U> const& r) noexcept;
505template<class T, class U>
506    shared_ptr<T> const_pointer_cast(shared_ptr<U> const& r) noexcept;
507
508// shared_ptr I/O:
509template<class E, class T, class Y>
510    basic_ostream<E, T>& operator<< (basic_ostream<E, T>& os, shared_ptr<Y> const& p);
511
512// shared_ptr get_deleter:
513template<class D, class T> D* get_deleter(shared_ptr<T> const& p) noexcept;
514
515template<class T, class... Args>
516    shared_ptr<T> make_shared(Args&&... args);
517template<class T, class A, class... Args>
518    shared_ptr<T> allocate_shared(const A& a, Args&&... args);
519
520template<class T>
521class weak_ptr
522{
523public:
524    typedef T element_type;
525
526    // constructors
527    constexpr weak_ptr() noexcept;
528    template<class Y> weak_ptr(shared_ptr<Y> const& r) noexcept;
529    weak_ptr(weak_ptr const& r) noexcept;
530    template<class Y> weak_ptr(weak_ptr<Y> const& r) noexcept;
531    weak_ptr(weak_ptr&& r) noexcept;                      // C++14
532    template<class Y> weak_ptr(weak_ptr<Y>&& r) noexcept; // C++14
533
534    // destructor
535    ~weak_ptr();
536
537    // assignment
538    weak_ptr& operator=(weak_ptr const& r) noexcept;
539    template<class Y> weak_ptr& operator=(weak_ptr<Y> const& r) noexcept;
540    template<class Y> weak_ptr& operator=(shared_ptr<Y> const& r) noexcept;
541    weak_ptr& operator=(weak_ptr&& r) noexcept;                      // C++14
542    template<class Y> weak_ptr& operator=(weak_ptr<Y>&& r) noexcept; // C++14
543
544    // modifiers
545    void swap(weak_ptr& r) noexcept;
546    void reset() noexcept;
547
548    // observers
549    long use_count() const noexcept;
550    bool expired() const noexcept;
551    shared_ptr<T> lock() const noexcept;
552    template<class U> bool owner_before(shared_ptr<U> const& b) const noexcept;
553    template<class U> bool owner_before(weak_ptr<U> const& b) const noexcept;
554};
555
556template<class T>
557weak_ptr(shared_ptr<T>) -> weak_ptr<T>;
558
559// weak_ptr specialized algorithms:
560template<class T> void swap(weak_ptr<T>& a, weak_ptr<T>& b) noexcept;
561
562// class owner_less:
563template<class T> struct owner_less;
564
565template<class T>
566struct owner_less<shared_ptr<T> >
567    : binary_function<shared_ptr<T>, shared_ptr<T>, bool>
568{
569    typedef bool result_type;
570    bool operator()(shared_ptr<T> const&, shared_ptr<T> const&) const noexcept;
571    bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const noexcept;
572    bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const noexcept;
573};
574
575template<class T>
576struct owner_less<weak_ptr<T> >
577    : binary_function<weak_ptr<T>, weak_ptr<T>, bool>
578{
579    typedef bool result_type;
580    bool operator()(weak_ptr<T> const&, weak_ptr<T> const&) const noexcept;
581    bool operator()(shared_ptr<T> const&, weak_ptr<T> const&) const noexcept;
582    bool operator()(weak_ptr<T> const&, shared_ptr<T> const&) const noexcept;
583};
584
585template <>  // Added in C++14
586struct owner_less<void>
587{
588    template <class _Tp, class _Up>
589    bool operator()( shared_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const noexcept;
590    template <class _Tp, class _Up>
591    bool operator()( shared_ptr<_Tp> const& __x,   weak_ptr<_Up> const& __y) const noexcept;
592    template <class _Tp, class _Up>
593    bool operator()(   weak_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const noexcept;
594    template <class _Tp, class _Up>
595    bool operator()(   weak_ptr<_Tp> const& __x,   weak_ptr<_Up> const& __y) const noexcept;
596
597    typedef void is_transparent;
598};
599
600template<class T>
601class enable_shared_from_this
602{
603protected:
604    constexpr enable_shared_from_this() noexcept;
605    enable_shared_from_this(enable_shared_from_this const&) noexcept;
606    enable_shared_from_this& operator=(enable_shared_from_this const&) noexcept;
607    ~enable_shared_from_this();
608public:
609    shared_ptr<T> shared_from_this();
610    shared_ptr<T const> shared_from_this() const;
611};
612
613template<class T>
614    bool atomic_is_lock_free(const shared_ptr<T>* p);
615template<class T>
616    shared_ptr<T> atomic_load(const shared_ptr<T>* p);
617template<class T>
618    shared_ptr<T> atomic_load_explicit(const shared_ptr<T>* p, memory_order mo);
619template<class T>
620    void atomic_store(shared_ptr<T>* p, shared_ptr<T> r);
621template<class T>
622    void atomic_store_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
623template<class T>
624    shared_ptr<T> atomic_exchange(shared_ptr<T>* p, shared_ptr<T> r);
625template<class T>
626    shared_ptr<T>
627    atomic_exchange_explicit(shared_ptr<T>* p, shared_ptr<T> r, memory_order mo);
628template<class T>
629    bool
630    atomic_compare_exchange_weak(shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
631template<class T>
632    bool
633    atomic_compare_exchange_strong( shared_ptr<T>* p, shared_ptr<T>* v, shared_ptr<T> w);
634template<class T>
635    bool
636    atomic_compare_exchange_weak_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
637                                          shared_ptr<T> w, memory_order success,
638                                          memory_order failure);
639template<class T>
640    bool
641    atomic_compare_exchange_strong_explicit(shared_ptr<T>* p, shared_ptr<T>* v,
642                                            shared_ptr<T> w, memory_order success,
643                                            memory_order failure);
644// Hash support
645template <class T> struct hash;
646template <class T, class D> struct hash<unique_ptr<T, D> >;
647template <class T> struct hash<shared_ptr<T> >;
648
649template <class T, class Alloc>
650  inline constexpr bool uses_allocator_v = uses_allocator<T, Alloc>::value;
651
652// Pointer safety
653enum class pointer_safety { relaxed, preferred, strict };
654void declare_reachable(void *p);
655template <class T> T *undeclare_reachable(T *p);
656void declare_no_pointers(char *p, size_t n);
657void undeclare_no_pointers(char *p, size_t n);
658pointer_safety get_pointer_safety() noexcept;
659
660void* align(size_t alignment, size_t size, void*& ptr, size_t& space);
661
662}  // std
663
664*/
665
666#include <__config>
667#include <type_traits>
668#include <typeinfo>
669#include <cstddef>
670#include <cstdint>
671#include <new>
672#include <utility>
673#include <limits>
674#include <iterator>
675#include <__functional_base>
676#include <iosfwd>
677#include <tuple>
678#include <stdexcept>
679#include <cstring>
680#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
681#  include <atomic>
682#endif
683#include <version>
684
685#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
686#pragma GCC system_header
687#endif
688
689_LIBCPP_PUSH_MACROS
690#include <__undef_macros>
691
692
693_LIBCPP_BEGIN_NAMESPACE_STD
694
695template <class _ValueType>
696inline _LIBCPP_INLINE_VISIBILITY
697_ValueType __libcpp_relaxed_load(_ValueType const* __value) {
698#if !defined(_LIBCPP_HAS_NO_THREADS) && \
699    defined(__ATOMIC_RELAXED) &&        \
700    (__has_builtin(__atomic_load_n) || defined(_LIBCPP_COMPILER_GCC))
701    return __atomic_load_n(__value, __ATOMIC_RELAXED);
702#else
703    return *__value;
704#endif
705}
706
707template <class _ValueType>
708inline _LIBCPP_INLINE_VISIBILITY
709_ValueType __libcpp_acquire_load(_ValueType const* __value) {
710#if !defined(_LIBCPP_HAS_NO_THREADS) && \
711    defined(__ATOMIC_ACQUIRE) &&        \
712    (__has_builtin(__atomic_load_n) || defined(_LIBCPP_COMPILER_GCC))
713    return __atomic_load_n(__value, __ATOMIC_ACQUIRE);
714#else
715    return *__value;
716#endif
717}
718
719// addressof moved to <type_traits>
720
721template <class _Tp> class allocator;
722
723#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS)
724template <>
725class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 allocator<void>
726{
727public:
728    typedef void*             pointer;
729    typedef const void*       const_pointer;
730    typedef void              value_type;
731
732    template <class _Up> struct rebind {typedef allocator<_Up> other;};
733};
734
735template <>
736class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX17 allocator<const void>
737{
738public:
739    typedef const void*       pointer;
740    typedef const void*       const_pointer;
741    typedef const void        value_type;
742
743    template <class _Up> struct rebind {typedef allocator<_Up> other;};
744};
745#endif
746
747// pointer_traits
748
749template <class _Tp, class = void>
750struct __has_element_type : false_type {};
751
752template <class _Tp>
753struct __has_element_type<_Tp,
754              typename __void_t<typename _Tp::element_type>::type> : true_type {};
755
756template <class _Ptr, bool = __has_element_type<_Ptr>::value>
757struct __pointer_traits_element_type;
758
759template <class _Ptr>
760struct __pointer_traits_element_type<_Ptr, true>
761{
762    typedef _LIBCPP_NODEBUG_TYPE typename _Ptr::element_type type;
763};
764
765#ifndef _LIBCPP_HAS_NO_VARIADICS
766
767template <template <class, class...> class _Sp, class _Tp, class ..._Args>
768struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, true>
769{
770    typedef _LIBCPP_NODEBUG_TYPE typename _Sp<_Tp, _Args...>::element_type type;
771};
772
773template <template <class, class...> class _Sp, class _Tp, class ..._Args>
774struct __pointer_traits_element_type<_Sp<_Tp, _Args...>, false>
775{
776    typedef _LIBCPP_NODEBUG_TYPE _Tp type;
777};
778
779#else  // _LIBCPP_HAS_NO_VARIADICS
780
781template <template <class> class _Sp, class _Tp>
782struct __pointer_traits_element_type<_Sp<_Tp>, true>
783{
784    typedef typename _Sp<_Tp>::element_type type;
785};
786
787template <template <class> class _Sp, class _Tp>
788struct __pointer_traits_element_type<_Sp<_Tp>, false>
789{
790    typedef _Tp type;
791};
792
793template <template <class, class> class _Sp, class _Tp, class _A0>
794struct __pointer_traits_element_type<_Sp<_Tp, _A0>, true>
795{
796    typedef typename _Sp<_Tp, _A0>::element_type type;
797};
798
799template <template <class, class> class _Sp, class _Tp, class _A0>
800struct __pointer_traits_element_type<_Sp<_Tp, _A0>, false>
801{
802    typedef _Tp type;
803};
804
805template <template <class, class, class> class _Sp, class _Tp, class _A0, class _A1>
806struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1>, true>
807{
808    typedef typename _Sp<_Tp, _A0, _A1>::element_type type;
809};
810
811template <template <class, class, class> class _Sp, class _Tp, class _A0, class _A1>
812struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1>, false>
813{
814    typedef _Tp type;
815};
816
817template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
818                                                           class _A1, class _A2>
819struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1, _A2>, true>
820{
821    typedef typename _Sp<_Tp, _A0, _A1, _A2>::element_type type;
822};
823
824template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
825                                                           class _A1, class _A2>
826struct __pointer_traits_element_type<_Sp<_Tp, _A0, _A1, _A2>, false>
827{
828    typedef _Tp type;
829};
830
831#endif  // _LIBCPP_HAS_NO_VARIADICS
832
833template <class _Tp, class = void>
834struct __has_difference_type : false_type {};
835
836template <class _Tp>
837struct __has_difference_type<_Tp,
838            typename __void_t<typename _Tp::difference_type>::type> : true_type {};
839
840template <class _Ptr, bool = __has_difference_type<_Ptr>::value>
841struct __pointer_traits_difference_type
842{
843    typedef _LIBCPP_NODEBUG_TYPE ptrdiff_t type;
844};
845
846template <class _Ptr>
847struct __pointer_traits_difference_type<_Ptr, true>
848{
849    typedef _LIBCPP_NODEBUG_TYPE typename _Ptr::difference_type type;
850};
851
852template <class _Tp, class _Up>
853struct __has_rebind
854{
855private:
856    struct __two {char __lx; char __lxx;};
857    template <class _Xp> static __two __test(...);
858    _LIBCPP_SUPPRESS_DEPRECATED_PUSH
859    template <class _Xp> static char __test(typename _Xp::template rebind<_Up>* = 0);
860    _LIBCPP_SUPPRESS_DEPRECATED_POP
861public:
862    static const bool value = sizeof(__test<_Tp>(0)) == 1;
863};
864
865template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
866struct __pointer_traits_rebind
867{
868#ifndef _LIBCPP_CXX03_LANG
869    typedef _LIBCPP_NODEBUG_TYPE typename _Tp::template rebind<_Up> type;
870#else
871    typedef _LIBCPP_NODEBUG_TYPE typename _Tp::template rebind<_Up>::other type;
872#endif
873};
874
875#ifndef _LIBCPP_HAS_NO_VARIADICS
876
877template <template <class, class...> class _Sp, class _Tp, class ..._Args, class _Up>
878struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, true>
879{
880#ifndef _LIBCPP_CXX03_LANG
881    typedef _LIBCPP_NODEBUG_TYPE typename _Sp<_Tp, _Args...>::template rebind<_Up> type;
882#else
883    typedef _LIBCPP_NODEBUG_TYPE typename _Sp<_Tp, _Args...>::template rebind<_Up>::other type;
884#endif
885};
886
887template <template <class, class...> class _Sp, class _Tp, class ..._Args, class _Up>
888struct __pointer_traits_rebind<_Sp<_Tp, _Args...>, _Up, false>
889{
890    typedef _Sp<_Up, _Args...> type;
891};
892
893#else  // _LIBCPP_HAS_NO_VARIADICS
894
895template <template <class> class _Sp, class _Tp, class _Up>
896struct __pointer_traits_rebind<_Sp<_Tp>, _Up, true>
897{
898#ifndef _LIBCPP_CXX03_LANG
899    typedef typename _Sp<_Tp>::template rebind<_Up> type;
900#else
901    typedef typename _Sp<_Tp>::template rebind<_Up>::other type;
902#endif
903};
904
905template <template <class> class _Sp, class _Tp, class _Up>
906struct __pointer_traits_rebind<_Sp<_Tp>, _Up, false>
907{
908    typedef _Sp<_Up> type;
909};
910
911template <template <class, class> class _Sp, class _Tp, class _A0, class _Up>
912struct __pointer_traits_rebind<_Sp<_Tp, _A0>, _Up, true>
913{
914#ifndef _LIBCPP_CXX03_LANG
915    typedef typename _Sp<_Tp, _A0>::template rebind<_Up> type;
916#else
917    typedef typename _Sp<_Tp, _A0>::template rebind<_Up>::other type;
918#endif
919};
920
921template <template <class, class> class _Sp, class _Tp, class _A0, class _Up>
922struct __pointer_traits_rebind<_Sp<_Tp, _A0>, _Up, false>
923{
924    typedef _Sp<_Up, _A0> type;
925};
926
927template <template <class, class, class> class _Sp, class _Tp, class _A0,
928                                         class _A1, class _Up>
929struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1>, _Up, true>
930{
931#ifndef _LIBCPP_CXX03_LANG
932    typedef typename _Sp<_Tp, _A0, _A1>::template rebind<_Up> type;
933#else
934    typedef typename _Sp<_Tp, _A0, _A1>::template rebind<_Up>::other type;
935#endif
936};
937
938template <template <class, class, class> class _Sp, class _Tp, class _A0,
939                                         class _A1, class _Up>
940struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1>, _Up, false>
941{
942    typedef _Sp<_Up, _A0, _A1> type;
943};
944
945template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
946                                                class _A1, class _A2, class _Up>
947struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1, _A2>, _Up, true>
948{
949#ifndef _LIBCPP_CXX03_LANG
950    typedef typename _Sp<_Tp, _A0, _A1, _A2>::template rebind<_Up> type;
951#else
952    typedef typename _Sp<_Tp, _A0, _A1, _A2>::template rebind<_Up>::other type;
953#endif
954};
955
956template <template <class, class, class, class> class _Sp, class _Tp, class _A0,
957                                                class _A1, class _A2, class _Up>
958struct __pointer_traits_rebind<_Sp<_Tp, _A0, _A1, _A2>, _Up, false>
959{
960    typedef _Sp<_Up, _A0, _A1, _A2> type;
961};
962
963#endif  // _LIBCPP_HAS_NO_VARIADICS
964
965template <class _Ptr>
966struct _LIBCPP_TEMPLATE_VIS pointer_traits
967{
968    typedef _Ptr                                                     pointer;
969    typedef typename __pointer_traits_element_type<pointer>::type    element_type;
970    typedef typename __pointer_traits_difference_type<pointer>::type difference_type;
971
972#ifndef _LIBCPP_CXX03_LANG
973    template <class _Up> using rebind = typename __pointer_traits_rebind<pointer, _Up>::type;
974#else
975    template <class _Up> struct rebind
976        {typedef typename __pointer_traits_rebind<pointer, _Up>::type other;};
977#endif  // _LIBCPP_CXX03_LANG
978
979private:
980    struct __nat {};
981public:
982    _LIBCPP_INLINE_VISIBILITY
983    static pointer pointer_to(typename conditional<is_void<element_type>::value,
984                                           __nat, element_type>::type& __r)
985        {return pointer::pointer_to(__r);}
986};
987
988template <class _Tp>
989struct _LIBCPP_TEMPLATE_VIS pointer_traits<_Tp*>
990{
991    typedef _Tp*      pointer;
992    typedef _Tp       element_type;
993    typedef ptrdiff_t difference_type;
994
995#ifndef _LIBCPP_CXX03_LANG
996    template <class _Up> using rebind = _Up*;
997#else
998    template <class _Up> struct rebind {typedef _Up* other;};
999#endif
1000
1001private:
1002    struct __nat {};
1003public:
1004    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1005    static pointer pointer_to(typename conditional<is_void<element_type>::value,
1006                                      __nat, element_type>::type& __r) _NOEXCEPT
1007        {return _VSTD::addressof(__r);}
1008};
1009
1010template <class _From, class _To>
1011struct __rebind_pointer {
1012#ifndef _LIBCPP_CXX03_LANG
1013    typedef typename pointer_traits<_From>::template rebind<_To>        type;
1014#else
1015    typedef typename pointer_traits<_From>::template rebind<_To>::other type;
1016#endif
1017};
1018
1019// allocator_traits
1020
1021template <class _Tp, class = void>
1022struct __has_pointer_type : false_type {};
1023
1024template <class _Tp>
1025struct __has_pointer_type<_Tp,
1026          typename __void_t<typename _Tp::pointer>::type> : true_type {};
1027
1028namespace __pointer_type_imp
1029{
1030
1031template <class _Tp, class _Dp, bool = __has_pointer_type<_Dp>::value>
1032struct __pointer_type
1033{
1034    typedef _LIBCPP_NODEBUG_TYPE typename _Dp::pointer type;
1035};
1036
1037template <class _Tp, class _Dp>
1038struct __pointer_type<_Tp, _Dp, false>
1039{
1040    typedef _LIBCPP_NODEBUG_TYPE _Tp* type;
1041};
1042
1043}  // __pointer_type_imp
1044
1045template <class _Tp, class _Dp>
1046struct __pointer_type
1047{
1048    typedef _LIBCPP_NODEBUG_TYPE typename __pointer_type_imp::__pointer_type<_Tp, typename remove_reference<_Dp>::type>::type type;
1049};
1050
1051template <class _Tp, class = void>
1052struct __has_const_pointer : false_type {};
1053
1054template <class _Tp>
1055struct __has_const_pointer<_Tp,
1056            typename __void_t<typename _Tp::const_pointer>::type> : true_type {};
1057
1058template <class _Tp, class _Ptr, class _Alloc, bool = __has_const_pointer<_Alloc>::value>
1059struct __const_pointer
1060{
1061    typedef _LIBCPP_NODEBUG_TYPE typename _Alloc::const_pointer type;
1062};
1063
1064template <class _Tp, class _Ptr, class _Alloc>
1065struct __const_pointer<_Tp, _Ptr, _Alloc, false>
1066{
1067#ifndef _LIBCPP_CXX03_LANG
1068    typedef _LIBCPP_NODEBUG_TYPE typename pointer_traits<_Ptr>::template rebind<const _Tp> type;
1069#else
1070    typedef typename pointer_traits<_Ptr>::template rebind<const _Tp>::other type;
1071#endif
1072};
1073
1074template <class _Tp, class = void>
1075struct __has_void_pointer : false_type {};
1076
1077template <class _Tp>
1078struct __has_void_pointer<_Tp,
1079               typename __void_t<typename _Tp::void_pointer>::type> : true_type {};
1080
1081template <class _Ptr, class _Alloc, bool = __has_void_pointer<_Alloc>::value>
1082struct __void_pointer
1083{
1084    typedef _LIBCPP_NODEBUG_TYPE typename _Alloc::void_pointer type;
1085};
1086
1087template <class _Ptr, class _Alloc>
1088struct __void_pointer<_Ptr, _Alloc, false>
1089{
1090#ifndef _LIBCPP_CXX03_LANG
1091    typedef _LIBCPP_NODEBUG_TYPE typename pointer_traits<_Ptr>::template rebind<void> type;
1092#else
1093    typedef _LIBCPP_NODEBUG_TYPE typename pointer_traits<_Ptr>::template rebind<void>::other type;
1094#endif
1095};
1096
1097template <class _Tp, class = void>
1098struct __has_const_void_pointer : false_type {};
1099
1100template <class _Tp>
1101struct __has_const_void_pointer<_Tp,
1102            typename __void_t<typename _Tp::const_void_pointer>::type> : true_type {};
1103
1104template <class _Ptr, class _Alloc, bool = __has_const_void_pointer<_Alloc>::value>
1105struct __const_void_pointer
1106{
1107    typedef _LIBCPP_NODEBUG_TYPE typename _Alloc::const_void_pointer type;
1108};
1109
1110template <class _Ptr, class _Alloc>
1111struct __const_void_pointer<_Ptr, _Alloc, false>
1112{
1113#ifndef _LIBCPP_CXX03_LANG
1114    typedef _LIBCPP_NODEBUG_TYPE typename pointer_traits<_Ptr>::template rebind<const void> type;
1115#else
1116    typedef _LIBCPP_NODEBUG_TYPE typename pointer_traits<_Ptr>::template rebind<const void>::other type;
1117#endif
1118};
1119
1120
1121template <bool _UsePointerTraits> struct __to_address_helper;
1122
1123template <> struct __to_address_helper<true> {
1124    template <class _Pointer>
1125    using __return_type = decltype(pointer_traits<_Pointer>::to_address(std::declval<const _Pointer&>()));
1126
1127    template <class _Pointer>
1128    _LIBCPP_CONSTEXPR
1129    static __return_type<_Pointer>
1130    __do_it(const _Pointer &__p) _NOEXCEPT { return pointer_traits<_Pointer>::to_address(__p); }
1131};
1132
1133template <class _Pointer, bool _Dummy = true>
1134using __choose_to_address = __to_address_helper<_IsValidExpansion<__to_address_helper<_Dummy>::template __return_type, _Pointer>::value>;
1135
1136
1137template <class _Tp>
1138inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1139_Tp*
1140__to_address(_Tp* __p) _NOEXCEPT
1141{
1142    static_assert(!is_function<_Tp>::value, "_Tp is a function type");
1143    return __p;
1144}
1145
1146template <class _Pointer>
1147inline _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
1148typename __choose_to_address<_Pointer>::template __return_type<_Pointer>
1149__to_address(const _Pointer& __p) _NOEXCEPT {
1150  return __choose_to_address<_Pointer>::__do_it(__p);
1151}
1152
1153template <> struct __to_address_helper<false> {
1154    template <class _Pointer>
1155    using __return_type = typename pointer_traits<_Pointer>::element_type*;
1156
1157    template <class _Pointer>
1158    _LIBCPP_CONSTEXPR
1159    static __return_type<_Pointer>
1160    __do_it(const _Pointer &__p) _NOEXCEPT { return std::__to_address(__p.operator->()); }
1161};
1162
1163
1164#if _LIBCPP_STD_VER > 17
1165template <class _Tp>
1166inline _LIBCPP_INLINE_VISIBILITY constexpr
1167_Tp*
1168to_address(_Tp* __p) _NOEXCEPT
1169{
1170    static_assert(!is_function_v<_Tp>, "_Tp is a function type");
1171    return __p;
1172}
1173
1174template <class _Pointer>
1175inline _LIBCPP_INLINE_VISIBILITY
1176auto
1177to_address(const _Pointer& __p) _NOEXCEPT
1178{
1179    return _VSTD::__to_address(__p);
1180}
1181#endif
1182
1183template <class _Tp, class = void>
1184struct __has_size_type : false_type {};
1185
1186template <class _Tp>
1187struct __has_size_type<_Tp,
1188               typename __void_t<typename _Tp::size_type>::type> : true_type {};
1189
1190template <class _Alloc, class _DiffType, bool = __has_size_type<_Alloc>::value>
1191struct __size_type
1192{
1193    typedef _LIBCPP_NODEBUG_TYPE typename make_unsigned<_DiffType>::type type;
1194};
1195
1196template <class _Alloc, class _DiffType>
1197struct __size_type<_Alloc, _DiffType, true>
1198{
1199    typedef _LIBCPP_NODEBUG_TYPE typename _Alloc::size_type type;
1200};
1201
1202template <class _Tp, class = void>
1203struct __has_propagate_on_container_copy_assignment : false_type {};
1204
1205template <class _Tp>
1206struct __has_propagate_on_container_copy_assignment<_Tp,
1207    typename __void_t<typename _Tp::propagate_on_container_copy_assignment>::type>
1208        : true_type {};
1209
1210template <class _Alloc, bool = __has_propagate_on_container_copy_assignment<_Alloc>::value>
1211struct __propagate_on_container_copy_assignment
1212{
1213    typedef _LIBCPP_NODEBUG_TYPE false_type type;
1214};
1215
1216template <class _Alloc>
1217struct __propagate_on_container_copy_assignment<_Alloc, true>
1218{
1219    typedef _LIBCPP_NODEBUG_TYPE typename _Alloc::propagate_on_container_copy_assignment type;
1220};
1221
1222template <class _Tp, class = void>
1223struct __has_propagate_on_container_move_assignment : false_type {};
1224
1225template <class _Tp>
1226struct __has_propagate_on_container_move_assignment<_Tp,
1227           typename __void_t<typename _Tp::propagate_on_container_move_assignment>::type>
1228               : true_type {};
1229
1230template <class _Alloc, bool = __has_propagate_on_container_move_assignment<_Alloc>::value>
1231struct __propagate_on_container_move_assignment
1232{
1233    typedef false_type type;
1234};
1235
1236template <class _Alloc>
1237struct __propagate_on_container_move_assignment<_Alloc, true>
1238{
1239    typedef _LIBCPP_NODEBUG_TYPE typename _Alloc::propagate_on_container_move_assignment type;
1240};
1241
1242template <class _Tp, class = void>
1243struct __has_propagate_on_container_swap : false_type {};
1244
1245template <class _Tp>
1246struct __has_propagate_on_container_swap<_Tp,
1247           typename __void_t<typename _Tp::propagate_on_container_swap>::type>
1248               : true_type {};
1249
1250template <class _Alloc, bool = __has_propagate_on_container_swap<_Alloc>::value>
1251struct __propagate_on_container_swap
1252{
1253    typedef false_type type;
1254};
1255
1256template <class _Alloc>
1257struct __propagate_on_container_swap<_Alloc, true>
1258{
1259    typedef _LIBCPP_NODEBUG_TYPE typename _Alloc::propagate_on_container_swap type;
1260};
1261
1262template <class _Tp, class = void>
1263struct __has_is_always_equal : false_type {};
1264
1265template <class _Tp>
1266struct __has_is_always_equal<_Tp,
1267           typename __void_t<typename _Tp::is_always_equal>::type>
1268               : true_type {};
1269
1270template <class _Alloc, bool = __has_is_always_equal<_Alloc>::value>
1271struct __is_always_equal
1272{
1273    typedef _LIBCPP_NODEBUG_TYPE typename _VSTD::is_empty<_Alloc>::type type;
1274};
1275
1276template <class _Alloc>
1277struct __is_always_equal<_Alloc, true>
1278{
1279    typedef _LIBCPP_NODEBUG_TYPE typename _Alloc::is_always_equal type;
1280};
1281
1282template <class _Tp, class _Up, bool = __has_rebind<_Tp, _Up>::value>
1283struct __has_rebind_other
1284{
1285private:
1286    struct __two {char __lx; char __lxx;};
1287    template <class _Xp> static __two __test(...);
1288    _LIBCPP_SUPPRESS_DEPRECATED_PUSH
1289    template <class _Xp> static char __test(typename _Xp::template rebind<_Up>::other* = 0);
1290    _LIBCPP_SUPPRESS_DEPRECATED_POP
1291public:
1292    static const bool value = sizeof(__test<_Tp>(0)) == 1;
1293};
1294
1295template <class _Tp, class _Up>
1296struct __has_rebind_other<_Tp, _Up, false>
1297{
1298    static const bool value = false;
1299};
1300
1301template <class _Tp, class _Up, bool = __has_rebind_other<_Tp, _Up>::value>
1302struct __allocator_traits_rebind
1303{
1304    _LIBCPP_SUPPRESS_DEPRECATED_PUSH
1305    typedef _LIBCPP_NODEBUG_TYPE typename _Tp::template rebind<_Up>::other type;
1306    _LIBCPP_SUPPRESS_DEPRECATED_POP
1307};
1308
1309#ifndef _LIBCPP_HAS_NO_VARIADICS
1310
1311template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up>
1312struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, true>
1313{
1314    _LIBCPP_SUPPRESS_DEPRECATED_PUSH
1315    typedef _LIBCPP_NODEBUG_TYPE typename _Alloc<_Tp, _Args...>::template rebind<_Up>::other type;
1316    _LIBCPP_SUPPRESS_DEPRECATED_POP
1317};
1318
1319template <template <class, class...> class _Alloc, class _Tp, class ..._Args, class _Up>
1320struct __allocator_traits_rebind<_Alloc<_Tp, _Args...>, _Up, false>
1321{
1322    typedef _LIBCPP_NODEBUG_TYPE _Alloc<_Up, _Args...> type;
1323};
1324
1325#else  // _LIBCPP_HAS_NO_VARIADICS
1326
1327template <template <class> class _Alloc, class _Tp, class _Up>
1328struct __allocator_traits_rebind<_Alloc<_Tp>, _Up, true>
1329{
1330    typedef typename _Alloc<_Tp>::template rebind<_Up>::other type;
1331};
1332
1333template <template <class> class _Alloc, class _Tp, class _Up>
1334struct __allocator_traits_rebind<_Alloc<_Tp>, _Up, false>
1335{
1336    typedef _Alloc<_Up> type;
1337};
1338
1339template <template <class, class> class _Alloc, class _Tp, class _A0, class _Up>
1340struct __allocator_traits_rebind<_Alloc<_Tp, _A0>, _Up, true>
1341{
1342    typedef typename _Alloc<_Tp, _A0>::template rebind<_Up>::other type;
1343};
1344
1345template <template <class, class> class _Alloc, class _Tp, class _A0, class _Up>
1346struct __allocator_traits_rebind<_Alloc<_Tp, _A0>, _Up, false>
1347{
1348    typedef _Alloc<_Up, _A0> type;
1349};
1350
1351template <template <class, class, class> class _Alloc, class _Tp, class _A0,
1352                                         class _A1, class _Up>
1353struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1>, _Up, true>
1354{
1355    typedef typename _Alloc<_Tp, _A0, _A1>::template rebind<_Up>::other type;
1356};
1357
1358template <template <class, class, class> class _Alloc, class _Tp, class _A0,
1359                                         class _A1, class _Up>
1360struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1>, _Up, false>
1361{
1362    typedef _Alloc<_Up, _A0, _A1> type;
1363};
1364
1365template <template <class, class, class, class> class _Alloc, class _Tp, class _A0,
1366                                                class _A1, class _A2, class _Up>
1367struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1, _A2>, _Up, true>
1368{
1369    typedef typename _Alloc<_Tp, _A0, _A1, _A2>::template rebind<_Up>::other type;
1370};
1371
1372template <template <class, class, class, class> class _Alloc, class _Tp, class _A0,
1373                                                class _A1, class _A2, class _Up>
1374struct __allocator_traits_rebind<_Alloc<_Tp, _A0, _A1, _A2>, _Up, false>
1375{
1376    typedef _Alloc<_Up, _A0, _A1, _A2> type;
1377};
1378
1379#endif  // _LIBCPP_HAS_NO_VARIADICS
1380
1381#ifndef _LIBCPP_CXX03_LANG
1382
1383_LIBCPP_SUPPRESS_DEPRECATED_PUSH
1384template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1385auto
1386__has_allocate_hint_test(_Alloc&& __a, _SizeType&& __sz, _ConstVoidPtr&& __p)
1387    -> decltype((void)__a.allocate(__sz, __p), true_type());
1388_LIBCPP_SUPPRESS_DEPRECATED_POP
1389
1390template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1391auto
1392__has_allocate_hint_test(const _Alloc& __a, _SizeType&& __sz, _ConstVoidPtr&& __p)
1393    -> false_type;
1394
1395template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1396struct __has_allocate_hint
1397    : decltype(_VSTD::__has_allocate_hint_test(declval<_Alloc>(),
1398                                               declval<_SizeType>(),
1399                                               declval<_ConstVoidPtr>()))
1400{
1401};
1402
1403#else  // _LIBCPP_CXX03_LANG
1404
1405template <class _Alloc, class _SizeType, class _ConstVoidPtr>
1406struct __has_allocate_hint
1407    : true_type
1408{
1409};
1410
1411#endif  // _LIBCPP_CXX03_LANG
1412
1413#if !defined(_LIBCPP_CXX03_LANG)
1414
1415_LIBCPP_SUPPRESS_DEPRECATED_PUSH
1416template <class _Alloc, class _Tp, class... _Args>
1417auto
1418__has_construct_test(_Alloc&& __a, _Tp* __p, _Args&&... __args)
1419    -> decltype(__a.construct(__p, _VSTD::forward<_Args>(__args)...), true_type());
1420_LIBCPP_SUPPRESS_DEPRECATED_POP
1421
1422template <class _Alloc, class _Pointer, class ..._Args>
1423auto
1424__has_construct_test(const _Alloc& __a, _Pointer&& __p, _Args&& ...__args)
1425    -> false_type;
1426
1427template <class _Alloc, class _Pointer, class ..._Args>
1428struct __has_construct
1429    : decltype(_VSTD::__has_construct_test(declval<_Alloc>(),
1430                                           declval<_Pointer>(),
1431                                           declval<_Args>()...))
1432{
1433};
1434
1435_LIBCPP_SUPPRESS_DEPRECATED_PUSH
1436template <class _Alloc, class _Pointer>
1437auto
1438__has_destroy_test(_Alloc&& __a, _Pointer&& __p)
1439    -> decltype(__a.destroy(__p), true_type());
1440_LIBCPP_SUPPRESS_DEPRECATED_POP
1441
1442template <class _Alloc, class _Pointer>
1443auto
1444__has_destroy_test(const _Alloc& __a, _Pointer&& __p)
1445    -> false_type;
1446
1447template <class _Alloc, class _Pointer>
1448struct __has_destroy
1449    : decltype(_VSTD::__has_destroy_test(declval<_Alloc>(),
1450                                         declval<_Pointer>()))
1451{
1452};
1453
1454_LIBCPP_SUPPRESS_DEPRECATED_PUSH
1455template <class _Alloc>
1456auto
1457__has_max_size_test(_Alloc&& __a)
1458    -> decltype(__a.max_size(), true_type());
1459_LIBCPP_SUPPRESS_DEPRECATED_POP
1460
1461template <class _Alloc>
1462auto
1463__has_max_size_test(const volatile _Alloc& __a)
1464    -> false_type;
1465
1466template <class _Alloc>
1467struct __has_max_size
1468    : decltype(_VSTD::__has_max_size_test(declval<_Alloc&>()))
1469{
1470};
1471
1472template <class _Alloc>
1473auto
1474__has_select_on_container_copy_construction_test(_Alloc&& __a)
1475    -> decltype(__a.select_on_container_copy_construction(), true_type());
1476
1477template <class _Alloc>
1478auto
1479__has_select_on_container_copy_construction_test(const volatile _Alloc& __a)
1480    -> false_type;
1481
1482template <class _Alloc>
1483struct __has_select_on_container_copy_construction
1484    : decltype(_VSTD::__has_select_on_container_copy_construction_test(declval<_Alloc&>()))
1485{
1486};
1487
1488#else  // _LIBCPP_CXX03_LANG
1489
1490template <class _Alloc, class _Pointer, class _Tp, class = void>
1491struct __has_construct : std::false_type {};
1492
1493template <class _Alloc, class _Pointer, class _Tp>
1494struct __has_construct<_Alloc, _Pointer, _Tp, typename __void_t<
1495    decltype(_VSTD::declval<_Alloc>().construct(_VSTD::declval<_Pointer>(), _VSTD::declval<_Tp>()))
1496>::type> : std::true_type {};
1497
1498template <class _Alloc, class _Pointer, class = void>
1499struct __has_destroy : false_type {};
1500
1501template <class _Alloc, class _Pointer>
1502struct __has_destroy<_Alloc, _Pointer, typename __void_t<
1503    decltype(_VSTD::declval<_Alloc>().destroy(_VSTD::declval<_Pointer>()))
1504>::type> : std::true_type {};
1505
1506template <class _Alloc>
1507struct __has_max_size
1508    : true_type
1509{
1510};
1511
1512template <class _Alloc>
1513struct __has_select_on_container_copy_construction
1514    : false_type
1515{
1516};
1517
1518#endif  // _LIBCPP_CXX03_LANG
1519
1520template <class _Alloc, class _Ptr, bool = __has_difference_type<_Alloc>::value>
1521struct __alloc_traits_difference_type
1522{
1523    typedef _LIBCPP_NODEBUG_TYPE typename pointer_traits<_Ptr>::difference_type type;
1524};
1525
1526template <class _Alloc, class _Ptr>
1527struct __alloc_traits_difference_type<_Alloc, _Ptr, true>
1528{
1529    typedef _LIBCPP_NODEBUG_TYPE typename _Alloc::difference_type type;
1530};
1531
1532template <class _Tp>
1533struct __is_default_allocator : false_type {};
1534
1535template <class _Tp>
1536struct __is_default_allocator<_VSTD::allocator<_Tp> > : true_type {};
1537
1538
1539
1540template <class _Alloc,
1541    bool = __has_construct<_Alloc, typename _Alloc::value_type*,  typename _Alloc::value_type&&>::value && !__is_default_allocator<_Alloc>::value
1542    >
1543struct __is_cpp17_move_insertable;
1544template <class _Alloc>
1545struct __is_cpp17_move_insertable<_Alloc, true> : std::true_type {};
1546template <class _Alloc>
1547struct __is_cpp17_move_insertable<_Alloc, false> : std::is_move_constructible<typename _Alloc::value_type> {};
1548
1549template <class _Alloc,
1550    bool = __has_construct<_Alloc, typename _Alloc::value_type*, const typename _Alloc::value_type&>::value && !__is_default_allocator<_Alloc>::value
1551    >
1552struct __is_cpp17_copy_insertable;
1553template <class _Alloc>
1554struct __is_cpp17_copy_insertable<_Alloc, true> : __is_cpp17_move_insertable<_Alloc> {};
1555template <class _Alloc>
1556struct __is_cpp17_copy_insertable<_Alloc, false> : integral_constant<bool,
1557    std::is_copy_constructible<typename _Alloc::value_type>::value &&
1558    __is_cpp17_move_insertable<_Alloc>::value>
1559  {};
1560
1561
1562
1563template <class _Alloc>
1564struct _LIBCPP_TEMPLATE_VIS allocator_traits
1565{
1566    typedef _Alloc                              allocator_type;
1567    typedef typename allocator_type::value_type value_type;
1568
1569    typedef typename __pointer_type<value_type, allocator_type>::type pointer;
1570    typedef typename __const_pointer<value_type, pointer, allocator_type>::type const_pointer;
1571    typedef typename __void_pointer<pointer, allocator_type>::type void_pointer;
1572    typedef typename __const_void_pointer<pointer, allocator_type>::type const_void_pointer;
1573
1574    typedef typename __alloc_traits_difference_type<allocator_type, pointer>::type difference_type;
1575    typedef typename __size_type<allocator_type, difference_type>::type size_type;
1576
1577    typedef typename __propagate_on_container_copy_assignment<allocator_type>::type
1578                     propagate_on_container_copy_assignment;
1579    typedef typename __propagate_on_container_move_assignment<allocator_type>::type
1580                     propagate_on_container_move_assignment;
1581    typedef typename __propagate_on_container_swap<allocator_type>::type
1582                     propagate_on_container_swap;
1583    typedef typename __is_always_equal<allocator_type>::type
1584                     is_always_equal;
1585
1586#ifndef _LIBCPP_CXX03_LANG
1587    template <class _Tp> using rebind_alloc =
1588                  typename __allocator_traits_rebind<allocator_type, _Tp>::type;
1589    template <class _Tp> using rebind_traits = allocator_traits<rebind_alloc<_Tp> >;
1590#else  // _LIBCPP_CXX03_LANG
1591    template <class _Tp> struct rebind_alloc
1592        {typedef typename __allocator_traits_rebind<allocator_type, _Tp>::type other;};
1593    template <class _Tp> struct rebind_traits
1594        {typedef allocator_traits<typename rebind_alloc<_Tp>::other> other;};
1595#endif  // _LIBCPP_CXX03_LANG
1596
1597    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
1598    static pointer allocate(allocator_type& __a, size_type __n)
1599        {return __a.allocate(__n);}
1600    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY
1601    static pointer allocate(allocator_type& __a, size_type __n, const_void_pointer __hint)
1602        {return __allocate(__a, __n, __hint,
1603            __has_allocate_hint<allocator_type, size_type, const_void_pointer>());}
1604
1605    _LIBCPP_INLINE_VISIBILITY
1606    static void deallocate(allocator_type& __a, pointer __p, size_type __n) _NOEXCEPT
1607        {__a.deallocate(__p, __n);}
1608
1609#ifndef _LIBCPP_HAS_NO_VARIADICS
1610    template <class _Tp, class... _Args>
1611        _LIBCPP_INLINE_VISIBILITY
1612        static void construct(allocator_type& __a, _Tp* __p, _Args&&... __args)
1613            {__construct(__has_construct<allocator_type, _Tp*, _Args...>(),
1614                         __a, __p, _VSTD::forward<_Args>(__args)...);}
1615#else  // _LIBCPP_HAS_NO_VARIADICS
1616    template <class _Tp>
1617        _LIBCPP_INLINE_VISIBILITY
1618        static void construct(allocator_type&, _Tp* __p)
1619            {
1620                ::new ((void*)__p) _Tp();
1621            }
1622    template <class _Tp, class _A0>
1623        _LIBCPP_INLINE_VISIBILITY
1624        static void construct(allocator_type& __a, _Tp* __p, const _A0& __a0)
1625            {
1626                __construct(__has_construct<allocator_type, _Tp*, const _A0&>(),
1627                            __a, __p, __a0);
1628            }
1629    template <class _Tp, class _A0, class _A1>
1630        _LIBCPP_INLINE_VISIBILITY
1631        static void construct(allocator_type&, _Tp* __p, const _A0& __a0,
1632                              const _A1& __a1)
1633            {
1634                ::new ((void*)__p) _Tp(__a0, __a1);
1635            }
1636    template <class _Tp, class _A0, class _A1, class _A2>
1637        _LIBCPP_INLINE_VISIBILITY
1638        static void construct(allocator_type&, _Tp* __p, const _A0& __a0,
1639                              const _A1& __a1, const _A2& __a2)
1640            {
1641                ::new ((void*)__p) _Tp(__a0, __a1, __a2);
1642            }
1643#endif  // _LIBCPP_HAS_NO_VARIADICS
1644
1645    template <class _Tp>
1646        _LIBCPP_INLINE_VISIBILITY
1647        static void destroy(allocator_type& __a, _Tp* __p)
1648            {__destroy(__has_destroy<allocator_type, _Tp*>(), __a, __p);}
1649
1650    _LIBCPP_INLINE_VISIBILITY
1651    static size_type max_size(const allocator_type& __a) _NOEXCEPT
1652        {return __max_size(__has_max_size<const allocator_type>(), __a);}
1653
1654    _LIBCPP_INLINE_VISIBILITY
1655    static allocator_type
1656        select_on_container_copy_construction(const allocator_type& __a)
1657            {return __select_on_container_copy_construction(
1658                __has_select_on_container_copy_construction<const allocator_type>(),
1659                __a);}
1660
1661    template <class _Ptr>
1662        _LIBCPP_INLINE_VISIBILITY
1663        static
1664        void
1665        __construct_forward_with_exception_guarantees(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __begin2)
1666        {
1667            static_assert(__is_cpp17_move_insertable<allocator_type>::value,
1668              "The specified type does not meet the requirements of Cpp17MoveInsertible");
1669            for (; __begin1 != __end1; ++__begin1, (void) ++__begin2)
1670              construct(__a, _VSTD::__to_address(__begin2),
1671#ifdef _LIBCPP_NO_EXCEPTIONS
1672                        _VSTD::move(*__begin1)
1673#else
1674                        _VSTD::move_if_noexcept(*__begin1)
1675#endif
1676                        );
1677        }
1678
1679    template <class _Tp>
1680        _LIBCPP_INLINE_VISIBILITY
1681        static
1682        typename enable_if
1683        <
1684            (__is_default_allocator<allocator_type>::value
1685                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1686             is_trivially_move_constructible<_Tp>::value,
1687            void
1688        >::type
1689        __construct_forward_with_exception_guarantees(allocator_type&, _Tp* __begin1, _Tp* __end1, _Tp*& __begin2)
1690        {
1691            ptrdiff_t _Np = __end1 - __begin1;
1692            if (_Np > 0)
1693            {
1694                _VSTD::memcpy(__begin2, __begin1, _Np * sizeof(_Tp));
1695                __begin2 += _Np;
1696            }
1697        }
1698
1699    template <class _Iter, class _Ptr>
1700        _LIBCPP_INLINE_VISIBILITY
1701        static
1702        void
1703        __construct_range_forward(allocator_type& __a, _Iter __begin1, _Iter __end1, _Ptr& __begin2)
1704        {
1705            for (; __begin1 != __end1; ++__begin1, (void) ++__begin2)
1706                construct(__a, _VSTD::__to_address(__begin2), *__begin1);
1707        }
1708
1709    template <class _SourceTp, class _DestTp,
1710              class _RawSourceTp = typename remove_const<_SourceTp>::type,
1711              class _RawDestTp = typename remove_const<_DestTp>::type>
1712        _LIBCPP_INLINE_VISIBILITY
1713        static
1714        typename enable_if
1715        <
1716            is_trivially_copy_constructible<_DestTp>::value &&
1717            is_same<_RawSourceTp, _RawDestTp>::value &&
1718            (__is_default_allocator<allocator_type>::value ||
1719             !__has_construct<allocator_type, _DestTp*, _SourceTp&>::value),
1720            void
1721        >::type
1722        __construct_range_forward(allocator_type&, _SourceTp* __begin1, _SourceTp* __end1, _DestTp*& __begin2)
1723        {
1724            ptrdiff_t _Np = __end1 - __begin1;
1725            if (_Np > 0)
1726            {
1727                _VSTD::memcpy(const_cast<_RawDestTp*>(__begin2), __begin1, _Np * sizeof(_DestTp));
1728                __begin2 += _Np;
1729            }
1730        }
1731
1732    template <class _Ptr>
1733        _LIBCPP_INLINE_VISIBILITY
1734        static
1735        void
1736        __construct_backward_with_exception_guarantees(allocator_type& __a, _Ptr __begin1, _Ptr __end1, _Ptr& __end2)
1737        {
1738            static_assert(__is_cpp17_move_insertable<allocator_type>::value,
1739              "The specified type does not meet the requirements of Cpp17MoveInsertable");
1740            while (__end1 != __begin1)
1741            {
1742              construct(__a, _VSTD::__to_address(__end2 - 1),
1743#ifdef _LIBCPP_NO_EXCEPTIONS
1744                        _VSTD::move(*--__end1)
1745#else
1746                        _VSTD::move_if_noexcept(*--__end1)
1747#endif
1748                        );
1749              --__end2;
1750            }
1751        }
1752
1753    template <class _Tp>
1754        _LIBCPP_INLINE_VISIBILITY
1755        static
1756        typename enable_if
1757        <
1758            (__is_default_allocator<allocator_type>::value
1759                || !__has_construct<allocator_type, _Tp*, _Tp>::value) &&
1760             is_trivially_move_constructible<_Tp>::value,
1761            void
1762        >::type
1763        __construct_backward_with_exception_guarantees(allocator_type&, _Tp* __begin1, _Tp* __end1, _Tp*& __end2)
1764        {
1765            ptrdiff_t _Np = __end1 - __begin1;
1766            __end2 -= _Np;
1767            if (_Np > 0)
1768                _VSTD::memcpy(__end2, __begin1, _Np * sizeof(_Tp));
1769        }
1770
1771private:
1772
1773    _LIBCPP_INLINE_VISIBILITY
1774    static pointer __allocate(allocator_type& __a, size_type __n,
1775        const_void_pointer __hint, true_type)
1776        {
1777            _LIBCPP_SUPPRESS_DEPRECATED_PUSH
1778            return __a.allocate(__n, __hint);
1779            _LIBCPP_SUPPRESS_DEPRECATED_POP
1780        }
1781    _LIBCPP_INLINE_VISIBILITY
1782    static pointer __allocate(allocator_type& __a, size_type __n,
1783        const_void_pointer, false_type)
1784        {return __a.allocate(__n);}
1785
1786#ifndef _LIBCPP_HAS_NO_VARIADICS
1787    template <class _Tp, class... _Args>
1788        _LIBCPP_INLINE_VISIBILITY
1789        static void __construct(true_type, allocator_type& __a, _Tp* __p, _Args&&... __args)
1790            {
1791                _LIBCPP_SUPPRESS_DEPRECATED_PUSH
1792                __a.construct(__p, _VSTD::forward<_Args>(__args)...);
1793                _LIBCPP_SUPPRESS_DEPRECATED_POP
1794            }
1795
1796    template <class _Tp, class... _Args>
1797        _LIBCPP_INLINE_VISIBILITY
1798        static void __construct(false_type, allocator_type&, _Tp* __p, _Args&&... __args)
1799            {
1800                ::new ((void*)__p) _Tp(_VSTD::forward<_Args>(__args)...);
1801            }
1802#else  // _LIBCPP_HAS_NO_VARIADICS
1803    template <class _Tp, class _A0>
1804        _LIBCPP_INLINE_VISIBILITY
1805        static void __construct(true_type, allocator_type& __a, _Tp* __p,
1806                                const _A0& __a0)
1807            {__a.construct(__p, __a0);}
1808    template <class _Tp, class _A0>
1809        _LIBCPP_INLINE_VISIBILITY
1810        static void __construct(false_type, allocator_type&, _Tp* __p,
1811                                const _A0& __a0)
1812            {
1813                ::new ((void*)__p) _Tp(__a0);
1814            }
1815#endif  // _LIBCPP_HAS_NO_VARIADICS
1816
1817    template <class _Tp>
1818        _LIBCPP_INLINE_VISIBILITY
1819        static void __destroy(true_type, allocator_type& __a, _Tp* __p)
1820            {
1821                _LIBCPP_SUPPRESS_DEPRECATED_PUSH
1822                __a.destroy(__p);
1823                _LIBCPP_SUPPRESS_DEPRECATED_POP
1824            }
1825    template <class _Tp>
1826        _LIBCPP_INLINE_VISIBILITY
1827        static void __destroy(false_type, allocator_type&, _Tp* __p)
1828            {
1829                __p->~_Tp();
1830            }
1831
1832    _LIBCPP_INLINE_VISIBILITY
1833    static size_type __max_size(true_type, const allocator_type& __a) _NOEXCEPT
1834            {
1835                _LIBCPP_SUPPRESS_DEPRECATED_PUSH
1836                return __a.max_size();
1837                _LIBCPP_SUPPRESS_DEPRECATED_POP
1838            }
1839
1840    _LIBCPP_INLINE_VISIBILITY
1841    static size_type __max_size(false_type, const allocator_type&) _NOEXCEPT
1842            {return numeric_limits<size_type>::max() / sizeof(value_type);}
1843
1844    _LIBCPP_INLINE_VISIBILITY
1845    static allocator_type
1846        __select_on_container_copy_construction(true_type, const allocator_type& __a)
1847            {return __a.select_on_container_copy_construction();}
1848    _LIBCPP_INLINE_VISIBILITY
1849    static allocator_type
1850        __select_on_container_copy_construction(false_type, const allocator_type& __a)
1851            {return __a;}
1852};
1853
1854template <class _Traits, class _Tp>
1855struct __rebind_alloc_helper
1856{
1857#ifndef _LIBCPP_CXX03_LANG
1858    typedef _LIBCPP_NODEBUG_TYPE typename _Traits::template rebind_alloc<_Tp>        type;
1859#else
1860    typedef typename _Traits::template rebind_alloc<_Tp>::other type;
1861#endif
1862};
1863
1864// allocator
1865
1866template <class _Tp>
1867class _LIBCPP_TEMPLATE_VIS allocator
1868{
1869public:
1870#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS)
1871    _LIBCPP_DEPRECATED_IN_CXX17 typedef size_t     size_type;
1872    _LIBCPP_DEPRECATED_IN_CXX17 typedef ptrdiff_t  difference_type;
1873    _LIBCPP_DEPRECATED_IN_CXX17 typedef _Tp*       pointer;
1874    _LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp* const_pointer;
1875    _LIBCPP_DEPRECATED_IN_CXX17 typedef _Tp&       reference;
1876    _LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp& const_reference;
1877
1878    template <class _Up> struct _LIBCPP_DEPRECATED_IN_CXX17 rebind {typedef allocator<_Up> other;};
1879#endif
1880
1881    typedef _Tp value_type;
1882
1883    typedef true_type propagate_on_container_move_assignment;
1884    typedef true_type is_always_equal;
1885
1886    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1887    allocator() _NOEXCEPT {}
1888
1889    template <class _Up>
1890    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
1891    allocator(const allocator<_Up>&) _NOEXCEPT {}
1892
1893#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS)
1894    _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY
1895    pointer address(reference __x) const _NOEXCEPT
1896        {return _VSTD::addressof(__x);}
1897    _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY
1898    const_pointer address(const_reference __x) const _NOEXCEPT
1899        {return _VSTD::addressof(__x);}
1900#endif
1901
1902    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _Tp* allocate(size_t __n)
1903        {
1904        // TODO(mpark): Replace with `allocator_traits<allocator>::max_size(*this)`.
1905        if (__n > (size_t(~0) / sizeof(_Tp)))
1906            __throw_length_error("allocator<T>::allocate(size_t n)"
1907                                 " 'n' exceeds maximum supported size");
1908        return static_cast<_Tp*>(_VSTD::__libcpp_allocate(__n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp)));
1909        }
1910
1911#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS)
1912    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _LIBCPP_DEPRECATED_IN_CXX17
1913    _Tp* allocate(size_t __n, const void*) { return allocate(__n); }
1914#endif
1915
1916    _LIBCPP_INLINE_VISIBILITY void deallocate(_Tp* __p, size_t __n) _NOEXCEPT
1917        {_VSTD::__libcpp_deallocate((void*)__p, __n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp));}
1918
1919#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS)
1920    _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT
1921        {return size_type(~0) / sizeof(_Tp);}
1922
1923#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1924    template <class _Up, class... _Args>
1925        _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY
1926        void
1927        construct(_Up* __p, _Args&&... __args)
1928        {
1929            ::new((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
1930        }
1931#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1932        _LIBCPP_INLINE_VISIBILITY
1933        void
1934        construct(pointer __p)
1935        {
1936            ::new((void*)__p) _Tp();
1937        }
1938# if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1939
1940    template <class _A0>
1941        _LIBCPP_INLINE_VISIBILITY
1942        void
1943        construct(pointer __p, _A0& __a0)
1944        {
1945            ::new((void*)__p) _Tp(__a0);
1946        }
1947    template <class _A0>
1948        _LIBCPP_INLINE_VISIBILITY
1949        void
1950        construct(pointer __p, const _A0& __a0)
1951        {
1952            ::new((void*)__p) _Tp(__a0);
1953        }
1954# endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
1955    template <class _A0, class _A1>
1956        _LIBCPP_INLINE_VISIBILITY
1957        void
1958        construct(pointer __p, _A0& __a0, _A1& __a1)
1959        {
1960            ::new((void*)__p) _Tp(__a0, __a1);
1961        }
1962    template <class _A0, class _A1>
1963        _LIBCPP_INLINE_VISIBILITY
1964        void
1965        construct(pointer __p, const _A0& __a0, _A1& __a1)
1966        {
1967            ::new((void*)__p) _Tp(__a0, __a1);
1968        }
1969    template <class _A0, class _A1>
1970        _LIBCPP_INLINE_VISIBILITY
1971        void
1972        construct(pointer __p, _A0& __a0, const _A1& __a1)
1973        {
1974            ::new((void*)__p) _Tp(__a0, __a1);
1975        }
1976    template <class _A0, class _A1>
1977        _LIBCPP_INLINE_VISIBILITY
1978        void
1979        construct(pointer __p, const _A0& __a0, const _A1& __a1)
1980        {
1981            ::new((void*)__p) _Tp(__a0, __a1);
1982        }
1983#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
1984    _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY void destroy(pointer __p) {__p->~_Tp();}
1985#endif
1986};
1987
1988template <class _Tp>
1989class _LIBCPP_TEMPLATE_VIS allocator<const _Tp>
1990{
1991public:
1992#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS)
1993    _LIBCPP_DEPRECATED_IN_CXX17 typedef size_t     size_type;
1994    _LIBCPP_DEPRECATED_IN_CXX17 typedef ptrdiff_t  difference_type;
1995    _LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp* pointer;
1996    _LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp* const_pointer;
1997    _LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp& reference;
1998    _LIBCPP_DEPRECATED_IN_CXX17 typedef const _Tp& const_reference;
1999
2000    template <class _Up> struct _LIBCPP_DEPRECATED_IN_CXX17 rebind {typedef allocator<_Up> other;};
2001#endif
2002
2003    typedef const _Tp value_type;
2004
2005    typedef true_type propagate_on_container_move_assignment;
2006    typedef true_type is_always_equal;
2007
2008    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2009    allocator() _NOEXCEPT {}
2010
2011    template <class _Up>
2012    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX17
2013    allocator(const allocator<_Up>&) _NOEXCEPT {}
2014
2015#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS)
2016    _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY
2017    const_pointer address(const_reference __x) const _NOEXCEPT
2018        {return _VSTD::addressof(__x);}
2019#endif
2020
2021    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY const _Tp* allocate(size_t __n)
2022    {
2023        // TODO(mpark): Replace with `allocator_traits<allocator>::max_size(*this)`.
2024        if (__n > (size_t(~0) / sizeof(_Tp)))
2025            __throw_length_error("allocator<const T>::allocate(size_t n)"
2026                                 " 'n' exceeds maximum supported size");
2027        return static_cast<const _Tp*>(_VSTD::__libcpp_allocate(__n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp)));
2028    }
2029
2030#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS)
2031    _LIBCPP_NODISCARD_AFTER_CXX17 _LIBCPP_INLINE_VISIBILITY _LIBCPP_DEPRECATED_IN_CXX17
2032    const _Tp* allocate(size_t __n, const void*) { return allocate(__n); }
2033#endif
2034
2035    _LIBCPP_INLINE_VISIBILITY void deallocate(const _Tp* __p, size_t __n)
2036        {_VSTD::__libcpp_deallocate((void*) const_cast<_Tp *>(__p), __n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp));}
2037
2038#if _LIBCPP_STD_VER <= 17 || defined(_LIBCPP_ENABLE_CXX20_REMOVED_ALLOCATOR_MEMBERS)
2039    _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY size_type max_size() const _NOEXCEPT
2040        {return size_type(~0) / sizeof(_Tp);}
2041
2042#if !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
2043    template <class _Up, class... _Args>
2044        _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY
2045        void
2046        construct(_Up* __p, _Args&&... __args)
2047        {
2048            ::new((void*)__p) _Up(_VSTD::forward<_Args>(__args)...);
2049        }
2050#else  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
2051        _LIBCPP_INLINE_VISIBILITY
2052        void
2053        construct(pointer __p)
2054        {
2055            ::new((void*) const_cast<_Tp *>(__p)) _Tp();
2056        }
2057# if defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2058
2059    template <class _A0>
2060        _LIBCPP_INLINE_VISIBILITY
2061        void
2062        construct(pointer __p, _A0& __a0)
2063        {
2064            ::new((void*) const_cast<_Tp *>(__p)) _Tp(__a0);
2065        }
2066    template <class _A0>
2067        _LIBCPP_INLINE_VISIBILITY
2068        void
2069        construct(pointer __p, const _A0& __a0)
2070        {
2071            ::new((void*) const_cast<_Tp *>(__p)) _Tp(__a0);
2072        }
2073# endif  // defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES)
2074    template <class _A0, class _A1>
2075        _LIBCPP_INLINE_VISIBILITY
2076        void
2077        construct(pointer __p, _A0& __a0, _A1& __a1)
2078        {
2079            ::new((void*) const_cast<_Tp *>(__p)) _Tp(__a0, __a1);
2080        }
2081    template <class _A0, class _A1>
2082        _LIBCPP_INLINE_VISIBILITY
2083        void
2084        construct(pointer __p, const _A0& __a0, _A1& __a1)
2085        {
2086            ::new((void*) const_cast<_Tp *>(__p)) _Tp(__a0, __a1);
2087        }
2088    template <class _A0, class _A1>
2089        _LIBCPP_INLINE_VISIBILITY
2090        void
2091        construct(pointer __p, _A0& __a0, const _A1& __a1)
2092        {
2093            ::new((void*) const_cast<_Tp *>(__p)) _Tp(__a0, __a1);
2094        }
2095    template <class _A0, class _A1>
2096        _LIBCPP_INLINE_VISIBILITY
2097        void
2098        construct(pointer __p, const _A0& __a0, const _A1& __a1)
2099        {
2100            ::new((void*) const_cast<_Tp *>(__p)) _Tp(__a0, __a1);
2101        }
2102#endif  // !defined(_LIBCPP_HAS_NO_RVALUE_REFERENCES) && !defined(_LIBCPP_HAS_NO_VARIADICS)
2103    _LIBCPP_DEPRECATED_IN_CXX17 _LIBCPP_INLINE_VISIBILITY void destroy(pointer __p) {__p->~_Tp();}
2104#endif
2105};
2106
2107template <class _Tp, class _Up>
2108inline _LIBCPP_INLINE_VISIBILITY
2109bool operator==(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return true;}
2110
2111template <class _Tp, class _Up>
2112inline _LIBCPP_INLINE_VISIBILITY
2113bool operator!=(const allocator<_Tp>&, const allocator<_Up>&) _NOEXCEPT {return false;}
2114
2115template <class _OutputIterator, class _Tp>
2116class _LIBCPP_TEMPLATE_VIS raw_storage_iterator
2117    : public iterator<output_iterator_tag,
2118                      _Tp,                                         // purposefully not C++03
2119                      ptrdiff_t,                                   // purposefully not C++03
2120                      _Tp*,                                        // purposefully not C++03
2121                      raw_storage_iterator<_OutputIterator, _Tp>&> // purposefully not C++03
2122{
2123private:
2124    _OutputIterator __x_;
2125public:
2126    _LIBCPP_INLINE_VISIBILITY explicit raw_storage_iterator(_OutputIterator __x) : __x_(__x) {}
2127    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator*() {return *this;}
2128    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(const _Tp& __element)
2129        {::new(_VSTD::addressof(*__x_)) _Tp(__element); return *this;}
2130#if _LIBCPP_STD_VER >= 14
2131    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator=(_Tp&& __element)
2132        {::new(_VSTD::addressof(*__x_)) _Tp(_VSTD::move(__element)); return *this;}
2133#endif
2134    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator& operator++() {++__x_; return *this;}
2135    _LIBCPP_INLINE_VISIBILITY raw_storage_iterator  operator++(int)
2136        {raw_storage_iterator __t(*this); ++__x_; return __t;}
2137#if _LIBCPP_STD_VER >= 14
2138    _LIBCPP_INLINE_VISIBILITY _OutputIterator base() const { return __x_; }
2139#endif
2140};
2141
2142template <class _Tp>
2143_LIBCPP_NODISCARD_EXT _LIBCPP_NO_CFI
2144pair<_Tp*, ptrdiff_t>
2145get_temporary_buffer(ptrdiff_t __n) _NOEXCEPT
2146{
2147    pair<_Tp*, ptrdiff_t> __r(0, 0);
2148    const ptrdiff_t __m = (~ptrdiff_t(0) ^
2149                           ptrdiff_t(ptrdiff_t(1) << (sizeof(ptrdiff_t) * __CHAR_BIT__ - 1)))
2150                           / sizeof(_Tp);
2151    if (__n > __m)
2152        __n = __m;
2153    while (__n > 0)
2154    {
2155#if !defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION)
2156    if (__is_overaligned_for_new(_LIBCPP_ALIGNOF(_Tp)))
2157        {
2158            std::align_val_t __al =
2159                std::align_val_t(std::alignment_of<_Tp>::value);
2160            __r.first = static_cast<_Tp*>(::operator new(
2161                __n * sizeof(_Tp), __al, nothrow));
2162        } else {
2163            __r.first = static_cast<_Tp*>(::operator new(
2164                __n * sizeof(_Tp), nothrow));
2165        }
2166#else
2167    if (__is_overaligned_for_new(_LIBCPP_ALIGNOF(_Tp)))
2168        {
2169            // Since aligned operator new is unavailable, return an empty
2170            // buffer rather than one with invalid alignment.
2171            return __r;
2172        }
2173
2174        __r.first = static_cast<_Tp*>(::operator new(__n * sizeof(_Tp), nothrow));
2175#endif
2176
2177        if (__r.first)
2178        {
2179            __r.second = __n;
2180            break;
2181        }
2182        __n /= 2;
2183    }
2184    return __r;
2185}
2186
2187template <class _Tp>
2188inline _LIBCPP_INLINE_VISIBILITY
2189void return_temporary_buffer(_Tp* __p) _NOEXCEPT
2190{
2191  _VSTD::__libcpp_deallocate_unsized((void*)__p, _LIBCPP_ALIGNOF(_Tp));
2192}
2193
2194#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
2195template <class _Tp>
2196struct _LIBCPP_DEPRECATED_IN_CXX11 auto_ptr_ref
2197{
2198    _Tp* __ptr_;
2199};
2200
2201template<class _Tp>
2202class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 auto_ptr
2203{
2204private:
2205    _Tp* __ptr_;
2206public:
2207    typedef _Tp element_type;
2208
2209    _LIBCPP_INLINE_VISIBILITY explicit auto_ptr(_Tp* __p = 0) _NOEXCEPT : __ptr_(__p) {}
2210    _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr& __p) _NOEXCEPT : __ptr_(__p.release()) {}
2211    template<class _Up> _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr<_Up>& __p) _NOEXCEPT
2212        : __ptr_(__p.release()) {}
2213    _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr& __p) _NOEXCEPT
2214        {reset(__p.release()); return *this;}
2215    template<class _Up> _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr<_Up>& __p) _NOEXCEPT
2216        {reset(__p.release()); return *this;}
2217    _LIBCPP_INLINE_VISIBILITY auto_ptr& operator=(auto_ptr_ref<_Tp> __p) _NOEXCEPT
2218        {reset(__p.__ptr_); return *this;}
2219    _LIBCPP_INLINE_VISIBILITY ~auto_ptr() _NOEXCEPT {delete __ptr_;}
2220
2221    _LIBCPP_INLINE_VISIBILITY _Tp& operator*() const _NOEXCEPT
2222        {return *__ptr_;}
2223    _LIBCPP_INLINE_VISIBILITY _Tp* operator->() const _NOEXCEPT {return __ptr_;}
2224    _LIBCPP_INLINE_VISIBILITY _Tp* get() const _NOEXCEPT {return __ptr_;}
2225    _LIBCPP_INLINE_VISIBILITY _Tp* release() _NOEXCEPT
2226    {
2227        _Tp* __t = __ptr_;
2228        __ptr_ = 0;
2229        return __t;
2230    }
2231    _LIBCPP_INLINE_VISIBILITY void reset(_Tp* __p = 0) _NOEXCEPT
2232    {
2233        if (__ptr_ != __p)
2234            delete __ptr_;
2235        __ptr_ = __p;
2236    }
2237
2238    _LIBCPP_INLINE_VISIBILITY auto_ptr(auto_ptr_ref<_Tp> __p) _NOEXCEPT : __ptr_(__p.__ptr_) {}
2239    template<class _Up> _LIBCPP_INLINE_VISIBILITY operator auto_ptr_ref<_Up>() _NOEXCEPT
2240        {auto_ptr_ref<_Up> __t; __t.__ptr_ = release(); return __t;}
2241    template<class _Up> _LIBCPP_INLINE_VISIBILITY operator auto_ptr<_Up>() _NOEXCEPT
2242        {return auto_ptr<_Up>(release());}
2243};
2244
2245template <>
2246class _LIBCPP_TEMPLATE_VIS _LIBCPP_DEPRECATED_IN_CXX11 auto_ptr<void>
2247{
2248public:
2249    typedef void element_type;
2250};
2251#endif
2252
2253// Tag used to default initialize one or both of the pair's elements.
2254struct __default_init_tag {};
2255struct __value_init_tag {};
2256
2257template <class _Tp, int _Idx,
2258          bool _CanBeEmptyBase =
2259              is_empty<_Tp>::value && !__libcpp_is_final<_Tp>::value>
2260struct __compressed_pair_elem {
2261  typedef _Tp _ParamT;
2262  typedef _Tp& reference;
2263  typedef const _Tp& const_reference;
2264
2265  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2266  __compressed_pair_elem(__default_init_tag) {}
2267  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2268  __compressed_pair_elem(__value_init_tag) : __value_() {}
2269
2270  template <class _Up, class = typename enable_if<
2271      !is_same<__compressed_pair_elem, typename decay<_Up>::type>::value
2272  >::type>
2273  _LIBCPP_INLINE_VISIBILITY
2274  _LIBCPP_CONSTEXPR explicit
2275  __compressed_pair_elem(_Up&& __u)
2276      : __value_(_VSTD::forward<_Up>(__u))
2277    {
2278    }
2279
2280
2281#ifndef _LIBCPP_CXX03_LANG
2282  template <class... _Args, size_t... _Indexes>
2283  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
2284  __compressed_pair_elem(piecewise_construct_t, tuple<_Args...> __args,
2285                         __tuple_indices<_Indexes...>)
2286      : __value_(_VSTD::forward<_Args>(_VSTD::get<_Indexes>(__args))...) {}
2287#endif
2288
2289
2290  _LIBCPP_INLINE_VISIBILITY reference __get() _NOEXCEPT { return __value_; }
2291  _LIBCPP_INLINE_VISIBILITY
2292  const_reference __get() const _NOEXCEPT { return __value_; }
2293
2294private:
2295  _Tp __value_;
2296};
2297
2298template <class _Tp, int _Idx>
2299struct __compressed_pair_elem<_Tp, _Idx, true> : private _Tp {
2300  typedef _Tp _ParamT;
2301  typedef _Tp& reference;
2302  typedef const _Tp& const_reference;
2303  typedef _Tp __value_type;
2304
2305  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR __compressed_pair_elem() = default;
2306  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2307  __compressed_pair_elem(__default_init_tag) {}
2308  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2309  __compressed_pair_elem(__value_init_tag) : __value_type() {}
2310
2311  template <class _Up, class = typename enable_if<
2312        !is_same<__compressed_pair_elem, typename decay<_Up>::type>::value
2313  >::type>
2314  _LIBCPP_INLINE_VISIBILITY
2315  _LIBCPP_CONSTEXPR explicit
2316  __compressed_pair_elem(_Up&& __u)
2317      : __value_type(_VSTD::forward<_Up>(__u))
2318  {}
2319
2320#ifndef _LIBCPP_CXX03_LANG
2321  template <class... _Args, size_t... _Indexes>
2322  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
2323  __compressed_pair_elem(piecewise_construct_t, tuple<_Args...> __args,
2324                         __tuple_indices<_Indexes...>)
2325      : __value_type(_VSTD::forward<_Args>(_VSTD::get<_Indexes>(__args))...) {}
2326#endif
2327
2328  _LIBCPP_INLINE_VISIBILITY reference __get() _NOEXCEPT { return *this; }
2329  _LIBCPP_INLINE_VISIBILITY
2330  const_reference __get() const _NOEXCEPT { return *this; }
2331};
2332
2333template <class _T1, class _T2>
2334class __compressed_pair : private __compressed_pair_elem<_T1, 0>,
2335                          private __compressed_pair_elem<_T2, 1> {
2336  typedef _LIBCPP_NODEBUG_TYPE __compressed_pair_elem<_T1, 0> _Base1;
2337  typedef _LIBCPP_NODEBUG_TYPE __compressed_pair_elem<_T2, 1> _Base2;
2338
2339  // NOTE: This static assert should never fire because __compressed_pair
2340  // is *almost never* used in a scenario where it's possible for T1 == T2.
2341  // (The exception is std::function where it is possible that the function
2342  //  object and the allocator have the same type).
2343  static_assert((!is_same<_T1, _T2>::value),
2344    "__compressed_pair cannot be instantated when T1 and T2 are the same type; "
2345    "The current implementation is NOT ABI-compatible with the previous "
2346    "implementation for this configuration");
2347
2348public:
2349    template <bool _Dummy = true,
2350      class = typename enable_if<
2351          __dependent_type<is_default_constructible<_T1>, _Dummy>::value &&
2352          __dependent_type<is_default_constructible<_T2>, _Dummy>::value
2353      >::type
2354  >
2355  _LIBCPP_INLINE_VISIBILITY
2356  _LIBCPP_CONSTEXPR __compressed_pair() : _Base1(__value_init_tag()), _Base2(__value_init_tag()) {}
2357
2358  template <class _U1, class _U2>
2359  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
2360  __compressed_pair(_U1&& __t1, _U2&& __t2)
2361      : _Base1(std::forward<_U1>(__t1)), _Base2(std::forward<_U2>(__t2)) {}
2362
2363#ifndef _LIBCPP_CXX03_LANG
2364  template <class... _Args1, class... _Args2>
2365  _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR_AFTER_CXX14
2366  __compressed_pair(piecewise_construct_t __pc, tuple<_Args1...> __first_args,
2367                    tuple<_Args2...> __second_args)
2368      : _Base1(__pc, _VSTD::move(__first_args),
2369               typename __make_tuple_indices<sizeof...(_Args1)>::type()),
2370        _Base2(__pc, _VSTD::move(__second_args),
2371               typename __make_tuple_indices<sizeof...(_Args2)>::type()) {}
2372#endif
2373
2374  _LIBCPP_INLINE_VISIBILITY
2375  typename _Base1::reference first() _NOEXCEPT {
2376    return static_cast<_Base1&>(*this).__get();
2377  }
2378
2379  _LIBCPP_INLINE_VISIBILITY
2380  typename _Base1::const_reference first() const _NOEXCEPT {
2381    return static_cast<_Base1 const&>(*this).__get();
2382  }
2383
2384  _LIBCPP_INLINE_VISIBILITY
2385  typename _Base2::reference second() _NOEXCEPT {
2386    return static_cast<_Base2&>(*this).__get();
2387  }
2388
2389  _LIBCPP_INLINE_VISIBILITY
2390  typename _Base2::const_reference second() const _NOEXCEPT {
2391    return static_cast<_Base2 const&>(*this).__get();
2392  }
2393
2394  _LIBCPP_INLINE_VISIBILITY
2395  void swap(__compressed_pair& __x)
2396    _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2397               __is_nothrow_swappable<_T2>::value)
2398  {
2399    using std::swap;
2400    swap(first(), __x.first());
2401    swap(second(), __x.second());
2402  }
2403};
2404
2405template <class _T1, class _T2>
2406inline _LIBCPP_INLINE_VISIBILITY
2407void swap(__compressed_pair<_T1, _T2>& __x, __compressed_pair<_T1, _T2>& __y)
2408    _NOEXCEPT_(__is_nothrow_swappable<_T1>::value &&
2409               __is_nothrow_swappable<_T2>::value) {
2410  __x.swap(__y);
2411}
2412
2413// default_delete
2414
2415template <class _Tp>
2416struct _LIBCPP_TEMPLATE_VIS default_delete {
2417    static_assert(!is_function<_Tp>::value,
2418                  "default_delete cannot be instantiated for function types");
2419#ifndef _LIBCPP_CXX03_LANG
2420  _LIBCPP_INLINE_VISIBILITY constexpr default_delete() _NOEXCEPT = default;
2421#else
2422  _LIBCPP_INLINE_VISIBILITY default_delete() {}
2423#endif
2424  template <class _Up>
2425  _LIBCPP_INLINE_VISIBILITY
2426  default_delete(const default_delete<_Up>&,
2427                 typename enable_if<is_convertible<_Up*, _Tp*>::value>::type* =
2428                     0) _NOEXCEPT {}
2429
2430  _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __ptr) const _NOEXCEPT {
2431    static_assert(sizeof(_Tp) > 0,
2432                  "default_delete can not delete incomplete type");
2433    static_assert(!is_void<_Tp>::value,
2434                  "default_delete can not delete incomplete type");
2435    delete __ptr;
2436  }
2437};
2438
2439template <class _Tp>
2440struct _LIBCPP_TEMPLATE_VIS default_delete<_Tp[]> {
2441private:
2442  template <class _Up>
2443  struct _EnableIfConvertible
2444      : enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value> {};
2445
2446public:
2447#ifndef _LIBCPP_CXX03_LANG
2448  _LIBCPP_INLINE_VISIBILITY constexpr default_delete() _NOEXCEPT = default;
2449#else
2450  _LIBCPP_INLINE_VISIBILITY default_delete() {}
2451#endif
2452
2453  template <class _Up>
2454  _LIBCPP_INLINE_VISIBILITY
2455  default_delete(const default_delete<_Up[]>&,
2456                 typename _EnableIfConvertible<_Up>::type* = 0) _NOEXCEPT {}
2457
2458  template <class _Up>
2459  _LIBCPP_INLINE_VISIBILITY
2460  typename _EnableIfConvertible<_Up>::type
2461  operator()(_Up* __ptr) const _NOEXCEPT {
2462    static_assert(sizeof(_Tp) > 0,
2463                  "default_delete can not delete incomplete type");
2464    static_assert(!is_void<_Tp>::value,
2465                  "default_delete can not delete void type");
2466    delete[] __ptr;
2467  }
2468};
2469
2470template <class _Deleter>
2471struct __unique_ptr_deleter_sfinae {
2472  static_assert(!is_reference<_Deleter>::value, "incorrect specialization");
2473  typedef const _Deleter& __lval_ref_type;
2474  typedef _Deleter&& __good_rval_ref_type;
2475  typedef true_type __enable_rval_overload;
2476};
2477
2478template <class _Deleter>
2479struct __unique_ptr_deleter_sfinae<_Deleter const&> {
2480  typedef const _Deleter& __lval_ref_type;
2481  typedef const _Deleter&& __bad_rval_ref_type;
2482  typedef false_type __enable_rval_overload;
2483};
2484
2485template <class _Deleter>
2486struct __unique_ptr_deleter_sfinae<_Deleter&> {
2487  typedef _Deleter& __lval_ref_type;
2488  typedef _Deleter&& __bad_rval_ref_type;
2489  typedef false_type __enable_rval_overload;
2490};
2491
2492template <class _Tp, class _Dp = default_delete<_Tp> >
2493class _LIBCPP_TEMPLATE_VIS unique_ptr {
2494public:
2495  typedef _Tp element_type;
2496  typedef _Dp deleter_type;
2497  typedef _LIBCPP_NODEBUG_TYPE typename __pointer_type<_Tp, deleter_type>::type pointer;
2498
2499  static_assert(!is_rvalue_reference<deleter_type>::value,
2500                "the specified deleter type cannot be an rvalue reference");
2501
2502private:
2503  __compressed_pair<pointer, deleter_type> __ptr_;
2504
2505  struct __nat { int __for_bool_; };
2506
2507  typedef _LIBCPP_NODEBUG_TYPE __unique_ptr_deleter_sfinae<_Dp> _DeleterSFINAE;
2508
2509  template <bool _Dummy>
2510  using _LValRefType _LIBCPP_NODEBUG_TYPE =
2511      typename __dependent_type<_DeleterSFINAE, _Dummy>::__lval_ref_type;
2512
2513  template <bool _Dummy>
2514  using _GoodRValRefType _LIBCPP_NODEBUG_TYPE =
2515      typename __dependent_type<_DeleterSFINAE, _Dummy>::__good_rval_ref_type;
2516
2517  template <bool _Dummy>
2518  using _BadRValRefType _LIBCPP_NODEBUG_TYPE  =
2519      typename __dependent_type<_DeleterSFINAE, _Dummy>::__bad_rval_ref_type;
2520
2521  template <bool _Dummy, class _Deleter = typename __dependent_type<
2522                             __identity<deleter_type>, _Dummy>::type>
2523  using _EnableIfDeleterDefaultConstructible _LIBCPP_NODEBUG_TYPE =
2524      typename enable_if<is_default_constructible<_Deleter>::value &&
2525                         !is_pointer<_Deleter>::value>::type;
2526
2527  template <class _ArgType>
2528  using _EnableIfDeleterConstructible _LIBCPP_NODEBUG_TYPE  =
2529      typename enable_if<is_constructible<deleter_type, _ArgType>::value>::type;
2530
2531  template <class _UPtr, class _Up>
2532  using _EnableIfMoveConvertible _LIBCPP_NODEBUG_TYPE  = typename enable_if<
2533      is_convertible<typename _UPtr::pointer, pointer>::value &&
2534      !is_array<_Up>::value
2535  >::type;
2536
2537  template <class _UDel>
2538  using _EnableIfDeleterConvertible _LIBCPP_NODEBUG_TYPE  = typename enable_if<
2539      (is_reference<_Dp>::value && is_same<_Dp, _UDel>::value) ||
2540      (!is_reference<_Dp>::value && is_convertible<_UDel, _Dp>::value)
2541    >::type;
2542
2543  template <class _UDel>
2544  using _EnableIfDeleterAssignable = typename enable_if<
2545      is_assignable<_Dp&, _UDel&&>::value
2546    >::type;
2547
2548public:
2549  template <bool _Dummy = true,
2550            class = _EnableIfDeleterDefaultConstructible<_Dummy> >
2551  _LIBCPP_INLINE_VISIBILITY
2552  _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT : __ptr_(pointer(), __default_init_tag()) {}
2553
2554  template <bool _Dummy = true,
2555            class = _EnableIfDeleterDefaultConstructible<_Dummy> >
2556  _LIBCPP_INLINE_VISIBILITY
2557  _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT : __ptr_(pointer(), __default_init_tag()) {}
2558
2559  template <bool _Dummy = true,
2560            class = _EnableIfDeleterDefaultConstructible<_Dummy> >
2561  _LIBCPP_INLINE_VISIBILITY
2562  explicit unique_ptr(pointer __p) _NOEXCEPT : __ptr_(__p, __default_init_tag()) {}
2563
2564  template <bool _Dummy = true,
2565            class = _EnableIfDeleterConstructible<_LValRefType<_Dummy> > >
2566  _LIBCPP_INLINE_VISIBILITY
2567  unique_ptr(pointer __p, _LValRefType<_Dummy> __d) _NOEXCEPT
2568      : __ptr_(__p, __d) {}
2569
2570  template <bool _Dummy = true,
2571            class = _EnableIfDeleterConstructible<_GoodRValRefType<_Dummy> > >
2572  _LIBCPP_INLINE_VISIBILITY
2573  unique_ptr(pointer __p, _GoodRValRefType<_Dummy> __d) _NOEXCEPT
2574      : __ptr_(__p, _VSTD::move(__d)) {
2575    static_assert(!is_reference<deleter_type>::value,
2576                  "rvalue deleter bound to reference");
2577  }
2578
2579  template <bool _Dummy = true,
2580            class = _EnableIfDeleterConstructible<_BadRValRefType<_Dummy> > >
2581  _LIBCPP_INLINE_VISIBILITY
2582  unique_ptr(pointer __p, _BadRValRefType<_Dummy> __d) = delete;
2583
2584  _LIBCPP_INLINE_VISIBILITY
2585  unique_ptr(unique_ptr&& __u) _NOEXCEPT
2586      : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {
2587  }
2588
2589  template <class _Up, class _Ep,
2590      class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
2591      class = _EnableIfDeleterConvertible<_Ep>
2592  >
2593  _LIBCPP_INLINE_VISIBILITY
2594  unique_ptr(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
2595      : __ptr_(__u.release(), _VSTD::forward<_Ep>(__u.get_deleter())) {}
2596
2597#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
2598  template <class _Up>
2599  _LIBCPP_INLINE_VISIBILITY
2600  unique_ptr(auto_ptr<_Up>&& __p,
2601             typename enable_if<is_convertible<_Up*, _Tp*>::value &&
2602                                    is_same<_Dp, default_delete<_Tp> >::value,
2603                                __nat>::type = __nat()) _NOEXCEPT
2604      : __ptr_(__p.release(), __default_init_tag()) {}
2605#endif
2606
2607  _LIBCPP_INLINE_VISIBILITY
2608  unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT {
2609    reset(__u.release());
2610    __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
2611    return *this;
2612  }
2613
2614  template <class _Up, class _Ep,
2615      class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
2616      class = _EnableIfDeleterAssignable<_Ep>
2617  >
2618  _LIBCPP_INLINE_VISIBILITY
2619  unique_ptr& operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT {
2620    reset(__u.release());
2621    __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2622    return *this;
2623  }
2624
2625#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
2626  template <class _Up>
2627  _LIBCPP_INLINE_VISIBILITY
2628      typename enable_if<is_convertible<_Up*, _Tp*>::value &&
2629                             is_same<_Dp, default_delete<_Tp> >::value,
2630                         unique_ptr&>::type
2631      operator=(auto_ptr<_Up> __p) {
2632    reset(__p.release());
2633    return *this;
2634  }
2635#endif
2636
2637#ifdef _LIBCPP_CXX03_LANG
2638  unique_ptr(unique_ptr const&) = delete;
2639  unique_ptr& operator=(unique_ptr const&) = delete;
2640#endif
2641
2642
2643  _LIBCPP_INLINE_VISIBILITY
2644  ~unique_ptr() { reset(); }
2645
2646  _LIBCPP_INLINE_VISIBILITY
2647  unique_ptr& operator=(nullptr_t) _NOEXCEPT {
2648    reset();
2649    return *this;
2650  }
2651
2652  _LIBCPP_INLINE_VISIBILITY
2653  typename add_lvalue_reference<_Tp>::type
2654  operator*() const {
2655    return *__ptr_.first();
2656  }
2657  _LIBCPP_INLINE_VISIBILITY
2658  pointer operator->() const _NOEXCEPT {
2659    return __ptr_.first();
2660  }
2661  _LIBCPP_INLINE_VISIBILITY
2662  pointer get() const _NOEXCEPT {
2663    return __ptr_.first();
2664  }
2665  _LIBCPP_INLINE_VISIBILITY
2666  deleter_type& get_deleter() _NOEXCEPT {
2667    return __ptr_.second();
2668  }
2669  _LIBCPP_INLINE_VISIBILITY
2670  const deleter_type& get_deleter() const _NOEXCEPT {
2671    return __ptr_.second();
2672  }
2673  _LIBCPP_INLINE_VISIBILITY
2674  _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {
2675    return __ptr_.first() != nullptr;
2676  }
2677
2678  _LIBCPP_INLINE_VISIBILITY
2679  pointer release() _NOEXCEPT {
2680    pointer __t = __ptr_.first();
2681    __ptr_.first() = pointer();
2682    return __t;
2683  }
2684
2685  _LIBCPP_INLINE_VISIBILITY
2686  void reset(pointer __p = pointer()) _NOEXCEPT {
2687    pointer __tmp = __ptr_.first();
2688    __ptr_.first() = __p;
2689    if (__tmp)
2690      __ptr_.second()(__tmp);
2691  }
2692
2693  _LIBCPP_INLINE_VISIBILITY
2694  void swap(unique_ptr& __u) _NOEXCEPT {
2695    __ptr_.swap(__u.__ptr_);
2696  }
2697};
2698
2699
2700template <class _Tp, class _Dp>
2701class _LIBCPP_TEMPLATE_VIS unique_ptr<_Tp[], _Dp> {
2702public:
2703  typedef _Tp element_type;
2704  typedef _Dp deleter_type;
2705  typedef typename __pointer_type<_Tp, deleter_type>::type pointer;
2706
2707private:
2708  __compressed_pair<pointer, deleter_type> __ptr_;
2709
2710  template <class _From>
2711  struct _CheckArrayPointerConversion : is_same<_From, pointer> {};
2712
2713  template <class _FromElem>
2714  struct _CheckArrayPointerConversion<_FromElem*>
2715      : integral_constant<bool,
2716          is_same<_FromElem*, pointer>::value ||
2717            (is_same<pointer, element_type*>::value &&
2718             is_convertible<_FromElem(*)[], element_type(*)[]>::value)
2719      >
2720  {};
2721
2722  typedef __unique_ptr_deleter_sfinae<_Dp> _DeleterSFINAE;
2723
2724  template <bool _Dummy>
2725  using _LValRefType _LIBCPP_NODEBUG_TYPE =
2726      typename __dependent_type<_DeleterSFINAE, _Dummy>::__lval_ref_type;
2727
2728  template <bool _Dummy>
2729  using _GoodRValRefType _LIBCPP_NODEBUG_TYPE =
2730      typename __dependent_type<_DeleterSFINAE, _Dummy>::__good_rval_ref_type;
2731
2732  template <bool _Dummy>
2733  using _BadRValRefType _LIBCPP_NODEBUG_TYPE =
2734      typename __dependent_type<_DeleterSFINAE, _Dummy>::__bad_rval_ref_type;
2735
2736  template <bool _Dummy, class _Deleter = typename __dependent_type<
2737                             __identity<deleter_type>, _Dummy>::type>
2738  using _EnableIfDeleterDefaultConstructible _LIBCPP_NODEBUG_TYPE  =
2739      typename enable_if<is_default_constructible<_Deleter>::value &&
2740                         !is_pointer<_Deleter>::value>::type;
2741
2742  template <class _ArgType>
2743  using _EnableIfDeleterConstructible _LIBCPP_NODEBUG_TYPE  =
2744      typename enable_if<is_constructible<deleter_type, _ArgType>::value>::type;
2745
2746  template <class _Pp>
2747  using _EnableIfPointerConvertible _LIBCPP_NODEBUG_TYPE  = typename enable_if<
2748      _CheckArrayPointerConversion<_Pp>::value
2749  >::type;
2750
2751  template <class _UPtr, class _Up,
2752        class _ElemT = typename _UPtr::element_type>
2753  using _EnableIfMoveConvertible _LIBCPP_NODEBUG_TYPE  = typename enable_if<
2754      is_array<_Up>::value &&
2755      is_same<pointer, element_type*>::value &&
2756      is_same<typename _UPtr::pointer, _ElemT*>::value &&
2757      is_convertible<_ElemT(*)[], element_type(*)[]>::value
2758    >::type;
2759
2760  template <class _UDel>
2761  using _EnableIfDeleterConvertible _LIBCPP_NODEBUG_TYPE  = typename enable_if<
2762      (is_reference<_Dp>::value && is_same<_Dp, _UDel>::value) ||
2763      (!is_reference<_Dp>::value && is_convertible<_UDel, _Dp>::value)
2764    >::type;
2765
2766  template <class _UDel>
2767  using _EnableIfDeleterAssignable _LIBCPP_NODEBUG_TYPE  = typename enable_if<
2768      is_assignable<_Dp&, _UDel&&>::value
2769    >::type;
2770
2771public:
2772  template <bool _Dummy = true,
2773            class = _EnableIfDeleterDefaultConstructible<_Dummy> >
2774  _LIBCPP_INLINE_VISIBILITY
2775  _LIBCPP_CONSTEXPR unique_ptr() _NOEXCEPT : __ptr_(pointer(), __default_init_tag()) {}
2776
2777  template <bool _Dummy = true,
2778            class = _EnableIfDeleterDefaultConstructible<_Dummy> >
2779  _LIBCPP_INLINE_VISIBILITY
2780  _LIBCPP_CONSTEXPR unique_ptr(nullptr_t) _NOEXCEPT : __ptr_(pointer(), __default_init_tag()) {}
2781
2782  template <class _Pp, bool _Dummy = true,
2783            class = _EnableIfDeleterDefaultConstructible<_Dummy>,
2784            class = _EnableIfPointerConvertible<_Pp> >
2785  _LIBCPP_INLINE_VISIBILITY
2786  explicit unique_ptr(_Pp __p) _NOEXCEPT
2787      : __ptr_(__p, __default_init_tag()) {}
2788
2789  template <class _Pp, bool _Dummy = true,
2790            class = _EnableIfDeleterConstructible<_LValRefType<_Dummy> >,
2791            class = _EnableIfPointerConvertible<_Pp> >
2792  _LIBCPP_INLINE_VISIBILITY
2793  unique_ptr(_Pp __p, _LValRefType<_Dummy> __d) _NOEXCEPT
2794      : __ptr_(__p, __d) {}
2795
2796  template <bool _Dummy = true,
2797            class = _EnableIfDeleterConstructible<_LValRefType<_Dummy> > >
2798  _LIBCPP_INLINE_VISIBILITY
2799  unique_ptr(nullptr_t, _LValRefType<_Dummy> __d) _NOEXCEPT
2800      : __ptr_(nullptr, __d) {}
2801
2802  template <class _Pp, bool _Dummy = true,
2803            class = _EnableIfDeleterConstructible<_GoodRValRefType<_Dummy> >,
2804            class = _EnableIfPointerConvertible<_Pp> >
2805  _LIBCPP_INLINE_VISIBILITY
2806  unique_ptr(_Pp __p, _GoodRValRefType<_Dummy> __d) _NOEXCEPT
2807      : __ptr_(__p, _VSTD::move(__d)) {
2808    static_assert(!is_reference<deleter_type>::value,
2809                  "rvalue deleter bound to reference");
2810  }
2811
2812  template <bool _Dummy = true,
2813            class = _EnableIfDeleterConstructible<_GoodRValRefType<_Dummy> > >
2814  _LIBCPP_INLINE_VISIBILITY
2815  unique_ptr(nullptr_t, _GoodRValRefType<_Dummy> __d) _NOEXCEPT
2816      : __ptr_(nullptr, _VSTD::move(__d)) {
2817    static_assert(!is_reference<deleter_type>::value,
2818                  "rvalue deleter bound to reference");
2819  }
2820
2821  template <class _Pp, bool _Dummy = true,
2822            class = _EnableIfDeleterConstructible<_BadRValRefType<_Dummy> >,
2823            class = _EnableIfPointerConvertible<_Pp> >
2824  _LIBCPP_INLINE_VISIBILITY
2825  unique_ptr(_Pp __p, _BadRValRefType<_Dummy> __d) = delete;
2826
2827  _LIBCPP_INLINE_VISIBILITY
2828  unique_ptr(unique_ptr&& __u) _NOEXCEPT
2829      : __ptr_(__u.release(), _VSTD::forward<deleter_type>(__u.get_deleter())) {
2830  }
2831
2832  _LIBCPP_INLINE_VISIBILITY
2833  unique_ptr& operator=(unique_ptr&& __u) _NOEXCEPT {
2834    reset(__u.release());
2835    __ptr_.second() = _VSTD::forward<deleter_type>(__u.get_deleter());
2836    return *this;
2837  }
2838
2839  template <class _Up, class _Ep,
2840      class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
2841      class = _EnableIfDeleterConvertible<_Ep>
2842  >
2843  _LIBCPP_INLINE_VISIBILITY
2844  unique_ptr(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT
2845      : __ptr_(__u.release(), _VSTD::forward<_Ep>(__u.get_deleter())) {
2846  }
2847
2848  template <class _Up, class _Ep,
2849      class = _EnableIfMoveConvertible<unique_ptr<_Up, _Ep>, _Up>,
2850      class = _EnableIfDeleterAssignable<_Ep>
2851  >
2852  _LIBCPP_INLINE_VISIBILITY
2853  unique_ptr&
2854  operator=(unique_ptr<_Up, _Ep>&& __u) _NOEXCEPT {
2855    reset(__u.release());
2856    __ptr_.second() = _VSTD::forward<_Ep>(__u.get_deleter());
2857    return *this;
2858  }
2859
2860#ifdef _LIBCPP_CXX03_LANG
2861  unique_ptr(unique_ptr const&) = delete;
2862  unique_ptr& operator=(unique_ptr const&) = delete;
2863#endif
2864
2865public:
2866  _LIBCPP_INLINE_VISIBILITY
2867  ~unique_ptr() { reset(); }
2868
2869  _LIBCPP_INLINE_VISIBILITY
2870  unique_ptr& operator=(nullptr_t) _NOEXCEPT {
2871    reset();
2872    return *this;
2873  }
2874
2875  _LIBCPP_INLINE_VISIBILITY
2876  typename add_lvalue_reference<_Tp>::type
2877  operator[](size_t __i) const {
2878    return __ptr_.first()[__i];
2879  }
2880  _LIBCPP_INLINE_VISIBILITY
2881  pointer get() const _NOEXCEPT {
2882    return __ptr_.first();
2883  }
2884
2885  _LIBCPP_INLINE_VISIBILITY
2886  deleter_type& get_deleter() _NOEXCEPT {
2887    return __ptr_.second();
2888  }
2889
2890  _LIBCPP_INLINE_VISIBILITY
2891  const deleter_type& get_deleter() const _NOEXCEPT {
2892    return __ptr_.second();
2893  }
2894  _LIBCPP_INLINE_VISIBILITY
2895  _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {
2896    return __ptr_.first() != nullptr;
2897  }
2898
2899  _LIBCPP_INLINE_VISIBILITY
2900  pointer release() _NOEXCEPT {
2901    pointer __t = __ptr_.first();
2902    __ptr_.first() = pointer();
2903    return __t;
2904  }
2905
2906  template <class _Pp>
2907  _LIBCPP_INLINE_VISIBILITY
2908  typename enable_if<
2909      _CheckArrayPointerConversion<_Pp>::value
2910  >::type
2911  reset(_Pp __p) _NOEXCEPT {
2912    pointer __tmp = __ptr_.first();
2913    __ptr_.first() = __p;
2914    if (__tmp)
2915      __ptr_.second()(__tmp);
2916  }
2917
2918  _LIBCPP_INLINE_VISIBILITY
2919  void reset(nullptr_t = nullptr) _NOEXCEPT {
2920    pointer __tmp = __ptr_.first();
2921    __ptr_.first() = nullptr;
2922    if (__tmp)
2923      __ptr_.second()(__tmp);
2924  }
2925
2926  _LIBCPP_INLINE_VISIBILITY
2927  void swap(unique_ptr& __u) _NOEXCEPT {
2928    __ptr_.swap(__u.__ptr_);
2929  }
2930
2931};
2932
2933template <class _Tp, class _Dp>
2934inline _LIBCPP_INLINE_VISIBILITY
2935typename enable_if<
2936    __is_swappable<_Dp>::value,
2937    void
2938>::type
2939swap(unique_ptr<_Tp, _Dp>& __x, unique_ptr<_Tp, _Dp>& __y) _NOEXCEPT {__x.swap(__y);}
2940
2941template <class _T1, class _D1, class _T2, class _D2>
2942inline _LIBCPP_INLINE_VISIBILITY
2943bool
2944operator==(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __x.get() == __y.get();}
2945
2946template <class _T1, class _D1, class _T2, class _D2>
2947inline _LIBCPP_INLINE_VISIBILITY
2948bool
2949operator!=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x == __y);}
2950
2951template <class _T1, class _D1, class _T2, class _D2>
2952inline _LIBCPP_INLINE_VISIBILITY
2953bool
2954operator< (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y)
2955{
2956    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
2957    typedef typename unique_ptr<_T2, _D2>::pointer _P2;
2958    typedef typename common_type<_P1, _P2>::type _Vp;
2959    return less<_Vp>()(__x.get(), __y.get());
2960}
2961
2962template <class _T1, class _D1, class _T2, class _D2>
2963inline _LIBCPP_INLINE_VISIBILITY
2964bool
2965operator> (const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return __y < __x;}
2966
2967template <class _T1, class _D1, class _T2, class _D2>
2968inline _LIBCPP_INLINE_VISIBILITY
2969bool
2970operator<=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__y < __x);}
2971
2972template <class _T1, class _D1, class _T2, class _D2>
2973inline _LIBCPP_INLINE_VISIBILITY
2974bool
2975operator>=(const unique_ptr<_T1, _D1>& __x, const unique_ptr<_T2, _D2>& __y) {return !(__x < __y);}
2976
2977template <class _T1, class _D1>
2978inline _LIBCPP_INLINE_VISIBILITY
2979bool
2980operator==(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
2981{
2982    return !__x;
2983}
2984
2985template <class _T1, class _D1>
2986inline _LIBCPP_INLINE_VISIBILITY
2987bool
2988operator==(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
2989{
2990    return !__x;
2991}
2992
2993template <class _T1, class _D1>
2994inline _LIBCPP_INLINE_VISIBILITY
2995bool
2996operator!=(const unique_ptr<_T1, _D1>& __x, nullptr_t) _NOEXCEPT
2997{
2998    return static_cast<bool>(__x);
2999}
3000
3001template <class _T1, class _D1>
3002inline _LIBCPP_INLINE_VISIBILITY
3003bool
3004operator!=(nullptr_t, const unique_ptr<_T1, _D1>& __x) _NOEXCEPT
3005{
3006    return static_cast<bool>(__x);
3007}
3008
3009template <class _T1, class _D1>
3010inline _LIBCPP_INLINE_VISIBILITY
3011bool
3012operator<(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3013{
3014    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
3015    return less<_P1>()(__x.get(), nullptr);
3016}
3017
3018template <class _T1, class _D1>
3019inline _LIBCPP_INLINE_VISIBILITY
3020bool
3021operator<(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3022{
3023    typedef typename unique_ptr<_T1, _D1>::pointer _P1;
3024    return less<_P1>()(nullptr, __x.get());
3025}
3026
3027template <class _T1, class _D1>
3028inline _LIBCPP_INLINE_VISIBILITY
3029bool
3030operator>(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3031{
3032    return nullptr < __x;
3033}
3034
3035template <class _T1, class _D1>
3036inline _LIBCPP_INLINE_VISIBILITY
3037bool
3038operator>(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3039{
3040    return __x < nullptr;
3041}
3042
3043template <class _T1, class _D1>
3044inline _LIBCPP_INLINE_VISIBILITY
3045bool
3046operator<=(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3047{
3048    return !(nullptr < __x);
3049}
3050
3051template <class _T1, class _D1>
3052inline _LIBCPP_INLINE_VISIBILITY
3053bool
3054operator<=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3055{
3056    return !(__x < nullptr);
3057}
3058
3059template <class _T1, class _D1>
3060inline _LIBCPP_INLINE_VISIBILITY
3061bool
3062operator>=(const unique_ptr<_T1, _D1>& __x, nullptr_t)
3063{
3064    return !(__x < nullptr);
3065}
3066
3067template <class _T1, class _D1>
3068inline _LIBCPP_INLINE_VISIBILITY
3069bool
3070operator>=(nullptr_t, const unique_ptr<_T1, _D1>& __x)
3071{
3072    return !(nullptr < __x);
3073}
3074
3075#if _LIBCPP_STD_VER > 11
3076
3077template<class _Tp>
3078struct __unique_if
3079{
3080    typedef unique_ptr<_Tp> __unique_single;
3081};
3082
3083template<class _Tp>
3084struct __unique_if<_Tp[]>
3085{
3086    typedef unique_ptr<_Tp[]> __unique_array_unknown_bound;
3087};
3088
3089template<class _Tp, size_t _Np>
3090struct __unique_if<_Tp[_Np]>
3091{
3092    typedef void __unique_array_known_bound;
3093};
3094
3095template<class _Tp, class... _Args>
3096inline _LIBCPP_INLINE_VISIBILITY
3097typename __unique_if<_Tp>::__unique_single
3098make_unique(_Args&&... __args)
3099{
3100    return unique_ptr<_Tp>(new _Tp(_VSTD::forward<_Args>(__args)...));
3101}
3102
3103template<class _Tp>
3104inline _LIBCPP_INLINE_VISIBILITY
3105typename __unique_if<_Tp>::__unique_array_unknown_bound
3106make_unique(size_t __n)
3107{
3108    typedef typename remove_extent<_Tp>::type _Up;
3109    return unique_ptr<_Tp>(new _Up[__n]());
3110}
3111
3112template<class _Tp, class... _Args>
3113    typename __unique_if<_Tp>::__unique_array_known_bound
3114    make_unique(_Args&&...) = delete;
3115
3116#endif  // _LIBCPP_STD_VER > 11
3117
3118template <class _Tp, class _Dp>
3119#ifdef _LIBCPP_CXX03_LANG
3120struct _LIBCPP_TEMPLATE_VIS hash<unique_ptr<_Tp, _Dp> >
3121#else
3122struct _LIBCPP_TEMPLATE_VIS hash<__enable_hash_helper<
3123    unique_ptr<_Tp, _Dp>, typename unique_ptr<_Tp, _Dp>::pointer> >
3124#endif
3125{
3126    typedef unique_ptr<_Tp, _Dp> argument_type;
3127    typedef size_t               result_type;
3128    _LIBCPP_INLINE_VISIBILITY
3129    result_type operator()(const argument_type& __ptr) const
3130    {
3131        typedef typename argument_type::pointer pointer;
3132        return hash<pointer>()(__ptr.get());
3133    }
3134};
3135
3136struct __destruct_n
3137{
3138private:
3139    size_t __size_;
3140
3141    template <class _Tp>
3142    _LIBCPP_INLINE_VISIBILITY void __process(_Tp* __p, false_type) _NOEXCEPT
3143        {for (size_t __i = 0; __i < __size_; ++__i, ++__p) __p->~_Tp();}
3144
3145    template <class _Tp>
3146    _LIBCPP_INLINE_VISIBILITY void __process(_Tp*, true_type) _NOEXCEPT
3147        {}
3148
3149    _LIBCPP_INLINE_VISIBILITY void __incr(false_type) _NOEXCEPT
3150        {++__size_;}
3151    _LIBCPP_INLINE_VISIBILITY void __incr(true_type) _NOEXCEPT
3152        {}
3153
3154    _LIBCPP_INLINE_VISIBILITY void __set(size_t __s, false_type) _NOEXCEPT
3155        {__size_ = __s;}
3156    _LIBCPP_INLINE_VISIBILITY void __set(size_t, true_type) _NOEXCEPT
3157        {}
3158public:
3159    _LIBCPP_INLINE_VISIBILITY explicit __destruct_n(size_t __s) _NOEXCEPT
3160        : __size_(__s) {}
3161
3162    template <class _Tp>
3163    _LIBCPP_INLINE_VISIBILITY void __incr(_Tp*) _NOEXCEPT
3164        {__incr(integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3165
3166    template <class _Tp>
3167    _LIBCPP_INLINE_VISIBILITY void __set(size_t __s, _Tp*) _NOEXCEPT
3168        {__set(__s, integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3169
3170    template <class _Tp>
3171    _LIBCPP_INLINE_VISIBILITY void operator()(_Tp* __p) _NOEXCEPT
3172        {__process(__p, integral_constant<bool, is_trivially_destructible<_Tp>::value>());}
3173};
3174
3175template <class _Alloc>
3176class __allocator_destructor
3177{
3178    typedef _LIBCPP_NODEBUG_TYPE allocator_traits<_Alloc> __alloc_traits;
3179public:
3180    typedef _LIBCPP_NODEBUG_TYPE typename __alloc_traits::pointer pointer;
3181    typedef _LIBCPP_NODEBUG_TYPE typename __alloc_traits::size_type size_type;
3182private:
3183    _Alloc& __alloc_;
3184    size_type __s_;
3185public:
3186    _LIBCPP_INLINE_VISIBILITY __allocator_destructor(_Alloc& __a, size_type __s)
3187             _NOEXCEPT
3188        : __alloc_(__a), __s_(__s) {}
3189    _LIBCPP_INLINE_VISIBILITY
3190    void operator()(pointer __p) _NOEXCEPT
3191        {__alloc_traits::deallocate(__alloc_, __p, __s_);}
3192};
3193
3194template <class _InputIterator, class _ForwardIterator>
3195_ForwardIterator
3196uninitialized_copy(_InputIterator __f, _InputIterator __l, _ForwardIterator __r)
3197{
3198    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3199#ifndef _LIBCPP_NO_EXCEPTIONS
3200    _ForwardIterator __s = __r;
3201    try
3202    {
3203#endif
3204        for (; __f != __l; ++__f, (void) ++__r)
3205            ::new (static_cast<void*>(_VSTD::addressof(*__r))) value_type(*__f);
3206#ifndef _LIBCPP_NO_EXCEPTIONS
3207    }
3208    catch (...)
3209    {
3210        for (; __s != __r; ++__s)
3211            __s->~value_type();
3212        throw;
3213    }
3214#endif
3215    return __r;
3216}
3217
3218template <class _InputIterator, class _Size, class _ForwardIterator>
3219_ForwardIterator
3220uninitialized_copy_n(_InputIterator __f, _Size __n, _ForwardIterator __r)
3221{
3222    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3223#ifndef _LIBCPP_NO_EXCEPTIONS
3224    _ForwardIterator __s = __r;
3225    try
3226    {
3227#endif
3228        for (; __n > 0; ++__f, (void) ++__r, (void) --__n)
3229            ::new (static_cast<void*>(_VSTD::addressof(*__r))) value_type(*__f);
3230#ifndef _LIBCPP_NO_EXCEPTIONS
3231    }
3232    catch (...)
3233    {
3234        for (; __s != __r; ++__s)
3235            __s->~value_type();
3236        throw;
3237    }
3238#endif
3239    return __r;
3240}
3241
3242template <class _ForwardIterator, class _Tp>
3243void
3244uninitialized_fill(_ForwardIterator __f, _ForwardIterator __l, const _Tp& __x)
3245{
3246    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3247#ifndef _LIBCPP_NO_EXCEPTIONS
3248    _ForwardIterator __s = __f;
3249    try
3250    {
3251#endif
3252        for (; __f != __l; ++__f)
3253            ::new (static_cast<void*>(_VSTD::addressof(*__f))) value_type(__x);
3254#ifndef _LIBCPP_NO_EXCEPTIONS
3255    }
3256    catch (...)
3257    {
3258        for (; __s != __f; ++__s)
3259            __s->~value_type();
3260        throw;
3261    }
3262#endif
3263}
3264
3265template <class _ForwardIterator, class _Size, class _Tp>
3266_ForwardIterator
3267uninitialized_fill_n(_ForwardIterator __f, _Size __n, const _Tp& __x)
3268{
3269    typedef typename iterator_traits<_ForwardIterator>::value_type value_type;
3270#ifndef _LIBCPP_NO_EXCEPTIONS
3271    _ForwardIterator __s = __f;
3272    try
3273    {
3274#endif
3275        for (; __n > 0; ++__f, (void) --__n)
3276            ::new (static_cast<void*>(_VSTD::addressof(*__f))) value_type(__x);
3277#ifndef _LIBCPP_NO_EXCEPTIONS
3278    }
3279    catch (...)
3280    {
3281        for (; __s != __f; ++__s)
3282            __s->~value_type();
3283        throw;
3284    }
3285#endif
3286    return __f;
3287}
3288
3289#if _LIBCPP_STD_VER > 14
3290
3291template <class _Tp>
3292inline _LIBCPP_INLINE_VISIBILITY
3293void destroy_at(_Tp* __loc) {
3294    _LIBCPP_ASSERT(__loc, "null pointer given to destroy_at");
3295    __loc->~_Tp();
3296}
3297
3298template <class _ForwardIterator>
3299inline _LIBCPP_INLINE_VISIBILITY
3300void destroy(_ForwardIterator __first, _ForwardIterator __last) {
3301    for (; __first != __last; ++__first)
3302        _VSTD::destroy_at(_VSTD::addressof(*__first));
3303}
3304
3305template <class _ForwardIterator, class _Size>
3306inline _LIBCPP_INLINE_VISIBILITY
3307_ForwardIterator destroy_n(_ForwardIterator __first, _Size __n) {
3308    for (; __n > 0; (void)++__first, --__n)
3309        _VSTD::destroy_at(_VSTD::addressof(*__first));
3310    return __first;
3311}
3312
3313template <class _ForwardIterator>
3314inline _LIBCPP_INLINE_VISIBILITY
3315void uninitialized_default_construct(_ForwardIterator __first, _ForwardIterator __last) {
3316    using _Vt = typename iterator_traits<_ForwardIterator>::value_type;
3317    auto __idx = __first;
3318#ifndef _LIBCPP_NO_EXCEPTIONS
3319    try {
3320#endif
3321    for (; __idx != __last; ++__idx)
3322        ::new((void*)_VSTD::addressof(*__idx)) _Vt;
3323#ifndef _LIBCPP_NO_EXCEPTIONS
3324    } catch (...) {
3325        _VSTD::destroy(__first, __idx);
3326        throw;
3327    }
3328#endif
3329}
3330
3331template <class _ForwardIterator, class _Size>
3332inline _LIBCPP_INLINE_VISIBILITY
3333_ForwardIterator uninitialized_default_construct_n(_ForwardIterator __first, _Size __n) {
3334    using _Vt = typename iterator_traits<_ForwardIterator>::value_type;
3335    auto __idx = __first;
3336#ifndef _LIBCPP_NO_EXCEPTIONS
3337    try {
3338#endif
3339    for (; __n > 0; (void)++__idx, --__n)
3340        ::new((void*)_VSTD::addressof(*__idx)) _Vt;
3341    return __idx;
3342#ifndef _LIBCPP_NO_EXCEPTIONS
3343    } catch (...) {
3344        _VSTD::destroy(__first, __idx);
3345        throw;
3346    }
3347#endif
3348}
3349
3350
3351template <class _ForwardIterator>
3352inline _LIBCPP_INLINE_VISIBILITY
3353void uninitialized_value_construct(_ForwardIterator __first, _ForwardIterator __last) {
3354    using _Vt = typename iterator_traits<_ForwardIterator>::value_type;
3355    auto __idx = __first;
3356#ifndef _LIBCPP_NO_EXCEPTIONS
3357    try {
3358#endif
3359    for (; __idx != __last; ++__idx)
3360        ::new((void*)_VSTD::addressof(*__idx)) _Vt();
3361#ifndef _LIBCPP_NO_EXCEPTIONS
3362    } catch (...) {
3363        _VSTD::destroy(__first, __idx);
3364        throw;
3365    }
3366#endif
3367}
3368
3369template <class _ForwardIterator, class _Size>
3370inline _LIBCPP_INLINE_VISIBILITY
3371_ForwardIterator uninitialized_value_construct_n(_ForwardIterator __first, _Size __n) {
3372    using _Vt = typename iterator_traits<_ForwardIterator>::value_type;
3373    auto __idx = __first;
3374#ifndef _LIBCPP_NO_EXCEPTIONS
3375    try {
3376#endif
3377    for (; __n > 0; (void)++__idx, --__n)
3378        ::new((void*)_VSTD::addressof(*__idx)) _Vt();
3379    return __idx;
3380#ifndef _LIBCPP_NO_EXCEPTIONS
3381    } catch (...) {
3382        _VSTD::destroy(__first, __idx);
3383        throw;
3384    }
3385#endif
3386}
3387
3388
3389template <class _InputIt, class _ForwardIt>
3390inline _LIBCPP_INLINE_VISIBILITY
3391_ForwardIt uninitialized_move(_InputIt __first, _InputIt __last, _ForwardIt __first_res) {
3392    using _Vt = typename iterator_traits<_ForwardIt>::value_type;
3393    auto __idx = __first_res;
3394#ifndef _LIBCPP_NO_EXCEPTIONS
3395    try {
3396#endif
3397    for (; __first != __last; (void)++__idx, ++__first)
3398        ::new((void*)_VSTD::addressof(*__idx)) _Vt(std::move(*__first));
3399    return __idx;
3400#ifndef _LIBCPP_NO_EXCEPTIONS
3401    } catch (...) {
3402        _VSTD::destroy(__first_res, __idx);
3403        throw;
3404    }
3405#endif
3406}
3407
3408template <class _InputIt, class _Size, class _ForwardIt>
3409inline _LIBCPP_INLINE_VISIBILITY
3410pair<_InputIt, _ForwardIt>
3411uninitialized_move_n(_InputIt __first, _Size __n, _ForwardIt __first_res) {
3412    using _Vt = typename iterator_traits<_ForwardIt>::value_type;
3413    auto __idx = __first_res;
3414#ifndef _LIBCPP_NO_EXCEPTIONS
3415    try {
3416#endif
3417    for (; __n > 0; ++__idx, (void)++__first, --__n)
3418        ::new((void*)_VSTD::addressof(*__idx)) _Vt(std::move(*__first));
3419    return {__first, __idx};
3420#ifndef _LIBCPP_NO_EXCEPTIONS
3421    } catch (...) {
3422        _VSTD::destroy(__first_res, __idx);
3423        throw;
3424    }
3425#endif
3426}
3427
3428
3429#endif // _LIBCPP_STD_VER > 14
3430
3431// NOTE: Relaxed and acq/rel atomics (for increment and decrement respectively)
3432// should be sufficient for thread safety.
3433// See https://bugs.llvm.org/show_bug.cgi?id=22803
3434#if defined(__clang__) && __has_builtin(__atomic_add_fetch)          \
3435                       && defined(__ATOMIC_RELAXED)                  \
3436                       && defined(__ATOMIC_ACQ_REL)
3437#   define _LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT
3438#elif defined(_LIBCPP_COMPILER_GCC)
3439#   define _LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT
3440#endif
3441
3442template <class _Tp>
3443inline _LIBCPP_INLINE_VISIBILITY _Tp
3444__libcpp_atomic_refcount_increment(_Tp& __t) _NOEXCEPT
3445{
3446#if defined(_LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT) && !defined(_LIBCPP_HAS_NO_THREADS)
3447    return __atomic_add_fetch(&__t, 1, __ATOMIC_RELAXED);
3448#else
3449    return __t += 1;
3450#endif
3451}
3452
3453template <class _Tp>
3454inline _LIBCPP_INLINE_VISIBILITY _Tp
3455__libcpp_atomic_refcount_decrement(_Tp& __t) _NOEXCEPT
3456{
3457#if defined(_LIBCPP_HAS_BUILTIN_ATOMIC_SUPPORT) && !defined(_LIBCPP_HAS_NO_THREADS)
3458    return __atomic_add_fetch(&__t, -1, __ATOMIC_ACQ_REL);
3459#else
3460    return __t -= 1;
3461#endif
3462}
3463
3464class _LIBCPP_EXCEPTION_ABI bad_weak_ptr
3465    : public std::exception
3466{
3467public:
3468    bad_weak_ptr() _NOEXCEPT = default;
3469    bad_weak_ptr(const bad_weak_ptr&) _NOEXCEPT = default;
3470    virtual ~bad_weak_ptr() _NOEXCEPT;
3471    virtual const char* what() const  _NOEXCEPT;
3472};
3473
3474_LIBCPP_NORETURN inline _LIBCPP_INLINE_VISIBILITY
3475void __throw_bad_weak_ptr()
3476{
3477#ifndef _LIBCPP_NO_EXCEPTIONS
3478    throw bad_weak_ptr();
3479#else
3480    _VSTD::abort();
3481#endif
3482}
3483
3484template<class _Tp> class _LIBCPP_TEMPLATE_VIS weak_ptr;
3485
3486class _LIBCPP_TYPE_VIS __shared_count
3487{
3488    __shared_count(const __shared_count&);
3489    __shared_count& operator=(const __shared_count&);
3490
3491protected:
3492    long __shared_owners_;
3493    virtual ~__shared_count();
3494private:
3495    virtual void __on_zero_shared() _NOEXCEPT = 0;
3496
3497public:
3498    _LIBCPP_INLINE_VISIBILITY
3499    explicit __shared_count(long __refs = 0) _NOEXCEPT
3500        : __shared_owners_(__refs) {}
3501
3502#if defined(_LIBCPP_BUILDING_LIBRARY) && \
3503    defined(_LIBCPP_DEPRECATED_ABI_LEGACY_LIBRARY_DEFINITIONS_FOR_INLINE_FUNCTIONS)
3504    void __add_shared() _NOEXCEPT;
3505    bool __release_shared() _NOEXCEPT;
3506#else
3507    _LIBCPP_INLINE_VISIBILITY
3508    void __add_shared() _NOEXCEPT {
3509      __libcpp_atomic_refcount_increment(__shared_owners_);
3510    }
3511    _LIBCPP_INLINE_VISIBILITY
3512    bool __release_shared() _NOEXCEPT {
3513      if (__libcpp_atomic_refcount_decrement(__shared_owners_) == -1) {
3514        __on_zero_shared();
3515        return true;
3516      }
3517      return false;
3518    }
3519#endif
3520    _LIBCPP_INLINE_VISIBILITY
3521    long use_count() const _NOEXCEPT {
3522        return __libcpp_relaxed_load(&__shared_owners_) + 1;
3523    }
3524};
3525
3526class _LIBCPP_TYPE_VIS __shared_weak_count
3527    : private __shared_count
3528{
3529    long __shared_weak_owners_;
3530
3531public:
3532    _LIBCPP_INLINE_VISIBILITY
3533    explicit __shared_weak_count(long __refs = 0) _NOEXCEPT
3534        : __shared_count(__refs),
3535          __shared_weak_owners_(__refs) {}
3536protected:
3537    virtual ~__shared_weak_count();
3538
3539public:
3540#if defined(_LIBCPP_BUILDING_LIBRARY) && \
3541    defined(_LIBCPP_DEPRECATED_ABI_LEGACY_LIBRARY_DEFINITIONS_FOR_INLINE_FUNCTIONS)
3542    void __add_shared() _NOEXCEPT;
3543    void __add_weak() _NOEXCEPT;
3544    void __release_shared() _NOEXCEPT;
3545#else
3546    _LIBCPP_INLINE_VISIBILITY
3547    void __add_shared() _NOEXCEPT {
3548      __shared_count::__add_shared();
3549    }
3550    _LIBCPP_INLINE_VISIBILITY
3551    void __add_weak() _NOEXCEPT {
3552      __libcpp_atomic_refcount_increment(__shared_weak_owners_);
3553    }
3554    _LIBCPP_INLINE_VISIBILITY
3555    void __release_shared() _NOEXCEPT {
3556      if (__shared_count::__release_shared())
3557        __release_weak();
3558    }
3559#endif
3560    void __release_weak() _NOEXCEPT;
3561    _LIBCPP_INLINE_VISIBILITY
3562    long use_count() const _NOEXCEPT {return __shared_count::use_count();}
3563    __shared_weak_count* lock() _NOEXCEPT;
3564
3565    // Define the function out only if we build static libc++ without RTTI.
3566    // Otherwise we may break clients who need to compile their projects with
3567    // -fno-rtti and yet link against a libc++.dylib compiled
3568    // without -fno-rtti.
3569#if !defined(_LIBCPP_NO_RTTI) || !defined(_LIBCPP_BUILD_STATIC)
3570    virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
3571#endif
3572private:
3573    virtual void __on_zero_shared_weak() _NOEXCEPT = 0;
3574};
3575
3576template <class _Tp, class _Dp, class _Alloc>
3577class __shared_ptr_pointer
3578    : public __shared_weak_count
3579{
3580    __compressed_pair<__compressed_pair<_Tp, _Dp>, _Alloc> __data_;
3581public:
3582    _LIBCPP_INLINE_VISIBILITY
3583    __shared_ptr_pointer(_Tp __p, _Dp __d, _Alloc __a)
3584        :  __data_(__compressed_pair<_Tp, _Dp>(__p, _VSTD::move(__d)), _VSTD::move(__a)) {}
3585
3586#ifndef _LIBCPP_NO_RTTI
3587    virtual const void* __get_deleter(const type_info&) const _NOEXCEPT;
3588#endif
3589
3590private:
3591    virtual void __on_zero_shared() _NOEXCEPT;
3592    virtual void __on_zero_shared_weak() _NOEXCEPT;
3593};
3594
3595#ifndef _LIBCPP_NO_RTTI
3596
3597template <class _Tp, class _Dp, class _Alloc>
3598const void*
3599__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__get_deleter(const type_info& __t) const _NOEXCEPT
3600{
3601    return __t == typeid(_Dp) ? _VSTD::addressof(__data_.first().second()) : nullptr;
3602}
3603
3604#endif  // _LIBCPP_NO_RTTI
3605
3606template <class _Tp, class _Dp, class _Alloc>
3607void
3608__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared() _NOEXCEPT
3609{
3610    __data_.first().second()(__data_.first().first());
3611    __data_.first().second().~_Dp();
3612}
3613
3614template <class _Tp, class _Dp, class _Alloc>
3615void
3616__shared_ptr_pointer<_Tp, _Dp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
3617{
3618    typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_pointer>::type _Al;
3619    typedef allocator_traits<_Al> _ATraits;
3620    typedef pointer_traits<typename _ATraits::pointer> _PTraits;
3621
3622    _Al __a(__data_.second());
3623    __data_.second().~_Alloc();
3624    __a.deallocate(_PTraits::pointer_to(*this), 1);
3625}
3626
3627template <class _Tp, class _Alloc>
3628class __shared_ptr_emplace
3629    : public __shared_weak_count
3630{
3631    __compressed_pair<_Alloc, _Tp> __data_;
3632public:
3633
3634    _LIBCPP_INLINE_VISIBILITY
3635    __shared_ptr_emplace(_Alloc __a)
3636        :  __data_(_VSTD::move(__a), __value_init_tag()) {}
3637
3638
3639#ifndef _LIBCPP_HAS_NO_VARIADICS
3640    template <class ..._Args>
3641        _LIBCPP_INLINE_VISIBILITY
3642        __shared_ptr_emplace(_Alloc __a, _Args&& ...__args)
3643            :  __data_(piecewise_construct, _VSTD::forward_as_tuple(__a),
3644                   _VSTD::forward_as_tuple(_VSTD::forward<_Args>(__args)...)) {}
3645#else  // _LIBCPP_HAS_NO_VARIADICS
3646
3647    template <class _A0>
3648        _LIBCPP_INLINE_VISIBILITY
3649        __shared_ptr_emplace(_Alloc __a, _A0& __a0)
3650            :  __data_(__a, _Tp(__a0)) {}
3651
3652    template <class _A0, class _A1>
3653        _LIBCPP_INLINE_VISIBILITY
3654        __shared_ptr_emplace(_Alloc __a, _A0& __a0, _A1& __a1)
3655            :  __data_(__a, _Tp(__a0, __a1)) {}
3656
3657    template <class _A0, class _A1, class _A2>
3658        _LIBCPP_INLINE_VISIBILITY
3659        __shared_ptr_emplace(_Alloc __a, _A0& __a0, _A1& __a1, _A2& __a2)
3660            :  __data_(__a, _Tp(__a0, __a1, __a2)) {}
3661
3662#endif  // _LIBCPP_HAS_NO_VARIADICS
3663
3664private:
3665    virtual void __on_zero_shared() _NOEXCEPT;
3666    virtual void __on_zero_shared_weak() _NOEXCEPT;
3667public:
3668    _LIBCPP_INLINE_VISIBILITY
3669    _Tp* get() _NOEXCEPT {return _VSTD::addressof(__data_.second());}
3670};
3671
3672template <class _Tp, class _Alloc>
3673void
3674__shared_ptr_emplace<_Tp, _Alloc>::__on_zero_shared() _NOEXCEPT
3675{
3676    __data_.second().~_Tp();
3677}
3678
3679template <class _Tp, class _Alloc>
3680void
3681__shared_ptr_emplace<_Tp, _Alloc>::__on_zero_shared_weak() _NOEXCEPT
3682{
3683    typedef typename __allocator_traits_rebind<_Alloc, __shared_ptr_emplace>::type _Al;
3684    typedef allocator_traits<_Al> _ATraits;
3685    typedef pointer_traits<typename _ATraits::pointer> _PTraits;
3686    _Al __a(__data_.first());
3687    __data_.first().~_Alloc();
3688    __a.deallocate(_PTraits::pointer_to(*this), 1);
3689}
3690
3691struct __shared_ptr_dummy_rebind_allocator_type;
3692template <>
3693class _LIBCPP_TEMPLATE_VIS allocator<__shared_ptr_dummy_rebind_allocator_type>
3694{
3695public:
3696    template <class _Other>
3697    struct rebind
3698    {
3699        typedef allocator<_Other> other;
3700    };
3701};
3702
3703template<class _Tp> class _LIBCPP_TEMPLATE_VIS enable_shared_from_this;
3704
3705template<class _Tp>
3706class _LIBCPP_TEMPLATE_VIS shared_ptr
3707{
3708public:
3709    typedef _Tp element_type;
3710
3711#if _LIBCPP_STD_VER > 14
3712    typedef weak_ptr<_Tp> weak_type;
3713#endif
3714private:
3715    element_type*      __ptr_;
3716    __shared_weak_count* __cntrl_;
3717
3718    struct __nat {int __for_bool_;};
3719public:
3720    _LIBCPP_INLINE_VISIBILITY
3721    _LIBCPP_CONSTEXPR shared_ptr() _NOEXCEPT;
3722    _LIBCPP_INLINE_VISIBILITY
3723    _LIBCPP_CONSTEXPR shared_ptr(nullptr_t) _NOEXCEPT;
3724    template<class _Yp>
3725        explicit shared_ptr(_Yp* __p,
3726                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3727    template<class _Yp, class _Dp>
3728        shared_ptr(_Yp* __p, _Dp __d,
3729                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3730    template<class _Yp, class _Dp, class _Alloc>
3731        shared_ptr(_Yp* __p, _Dp __d, _Alloc __a,
3732                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3733    template <class _Dp> shared_ptr(nullptr_t __p, _Dp __d);
3734    template <class _Dp, class _Alloc> shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a);
3735    template<class _Yp> _LIBCPP_INLINE_VISIBILITY shared_ptr(const shared_ptr<_Yp>& __r, element_type* __p) _NOEXCEPT;
3736    _LIBCPP_INLINE_VISIBILITY
3737    shared_ptr(const shared_ptr& __r) _NOEXCEPT;
3738    template<class _Yp>
3739        _LIBCPP_INLINE_VISIBILITY
3740        shared_ptr(const shared_ptr<_Yp>& __r,
3741                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat())
3742                       _NOEXCEPT;
3743#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3744    _LIBCPP_INLINE_VISIBILITY
3745    shared_ptr(shared_ptr&& __r) _NOEXCEPT;
3746    template<class _Yp> _LIBCPP_INLINE_VISIBILITY  shared_ptr(shared_ptr<_Yp>&& __r,
3747                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat())
3748                       _NOEXCEPT;
3749#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3750    template<class _Yp> explicit shared_ptr(const weak_ptr<_Yp>& __r,
3751                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type= __nat());
3752#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
3753#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3754    template<class _Yp>
3755        shared_ptr(auto_ptr<_Yp>&& __r,
3756                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3757#else
3758    template<class _Yp>
3759        shared_ptr(auto_ptr<_Yp> __r,
3760                   typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type = __nat());
3761#endif
3762#endif
3763#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3764    template <class _Yp, class _Dp>
3765        shared_ptr(unique_ptr<_Yp, _Dp>&&,
3766                   typename enable_if
3767                   <
3768                       !is_lvalue_reference<_Dp>::value &&
3769                       !is_array<_Yp>::value &&
3770                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3771                       __nat
3772                   >::type = __nat());
3773    template <class _Yp, class _Dp>
3774        shared_ptr(unique_ptr<_Yp, _Dp>&&,
3775                   typename enable_if
3776                   <
3777                       is_lvalue_reference<_Dp>::value &&
3778                       !is_array<_Yp>::value &&
3779                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3780                       __nat
3781                   >::type = __nat());
3782#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3783    template <class _Yp, class _Dp>
3784        shared_ptr(unique_ptr<_Yp, _Dp>,
3785                   typename enable_if
3786                   <
3787                       !is_lvalue_reference<_Dp>::value &&
3788                       !is_array<_Yp>::value &&
3789                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3790                       __nat
3791                   >::type = __nat());
3792    template <class _Yp, class _Dp>
3793        shared_ptr(unique_ptr<_Yp, _Dp>,
3794                   typename enable_if
3795                   <
3796                       is_lvalue_reference<_Dp>::value &&
3797                       !is_array<_Yp>::value &&
3798                       is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3799                       __nat
3800                   >::type = __nat());
3801#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3802
3803    ~shared_ptr();
3804
3805    _LIBCPP_INLINE_VISIBILITY
3806    shared_ptr& operator=(const shared_ptr& __r) _NOEXCEPT;
3807    template<class _Yp>
3808        typename enable_if
3809        <
3810            is_convertible<_Yp*, element_type*>::value,
3811            shared_ptr&
3812        >::type
3813        _LIBCPP_INLINE_VISIBILITY
3814        operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT;
3815#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3816    _LIBCPP_INLINE_VISIBILITY
3817    shared_ptr& operator=(shared_ptr&& __r) _NOEXCEPT;
3818    template<class _Yp>
3819        typename enable_if
3820        <
3821            is_convertible<_Yp*, element_type*>::value,
3822            shared_ptr<_Tp>&
3823        >::type
3824        _LIBCPP_INLINE_VISIBILITY
3825        operator=(shared_ptr<_Yp>&& __r);
3826#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
3827    template<class _Yp>
3828        _LIBCPP_INLINE_VISIBILITY
3829        typename enable_if
3830        <
3831            !is_array<_Yp>::value &&
3832            is_convertible<_Yp*, element_type*>::value,
3833            shared_ptr
3834        >::type&
3835        operator=(auto_ptr<_Yp>&& __r);
3836#endif
3837#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3838#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
3839    template<class _Yp>
3840        _LIBCPP_INLINE_VISIBILITY
3841        typename enable_if
3842        <
3843            !is_array<_Yp>::value &&
3844            is_convertible<_Yp*, element_type*>::value,
3845            shared_ptr&
3846        >::type
3847        operator=(auto_ptr<_Yp> __r);
3848#endif
3849#endif
3850    template <class _Yp, class _Dp>
3851        typename enable_if
3852        <
3853            !is_array<_Yp>::value &&
3854            is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
3855            shared_ptr&
3856        >::type
3857#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
3858        _LIBCPP_INLINE_VISIBILITY
3859        operator=(unique_ptr<_Yp, _Dp>&& __r);
3860#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
3861        _LIBCPP_INLINE_VISIBILITY
3862        operator=(unique_ptr<_Yp, _Dp> __r);
3863#endif
3864
3865    _LIBCPP_INLINE_VISIBILITY
3866    void swap(shared_ptr& __r) _NOEXCEPT;
3867    _LIBCPP_INLINE_VISIBILITY
3868    void reset() _NOEXCEPT;
3869    template<class _Yp>
3870        typename enable_if
3871        <
3872            is_convertible<_Yp*, element_type*>::value,
3873            void
3874        >::type
3875        _LIBCPP_INLINE_VISIBILITY
3876        reset(_Yp* __p);
3877    template<class _Yp, class _Dp>
3878        typename enable_if
3879        <
3880            is_convertible<_Yp*, element_type*>::value,
3881            void
3882        >::type
3883        _LIBCPP_INLINE_VISIBILITY
3884        reset(_Yp* __p, _Dp __d);
3885    template<class _Yp, class _Dp, class _Alloc>
3886        typename enable_if
3887        <
3888            is_convertible<_Yp*, element_type*>::value,
3889            void
3890        >::type
3891        _LIBCPP_INLINE_VISIBILITY
3892        reset(_Yp* __p, _Dp __d, _Alloc __a);
3893
3894    _LIBCPP_INLINE_VISIBILITY
3895    element_type* get() const _NOEXCEPT {return __ptr_;}
3896    _LIBCPP_INLINE_VISIBILITY
3897    typename add_lvalue_reference<element_type>::type operator*() const _NOEXCEPT
3898        {return *__ptr_;}
3899    _LIBCPP_INLINE_VISIBILITY
3900    element_type* operator->() const _NOEXCEPT {return __ptr_;}
3901    _LIBCPP_INLINE_VISIBILITY
3902    long use_count() const _NOEXCEPT {return __cntrl_ ? __cntrl_->use_count() : 0;}
3903    _LIBCPP_INLINE_VISIBILITY
3904    bool unique() const _NOEXCEPT {return use_count() == 1;}
3905    _LIBCPP_INLINE_VISIBILITY
3906    _LIBCPP_EXPLICIT operator bool() const _NOEXCEPT {return get() != 0;}
3907    template <class _Up>
3908        _LIBCPP_INLINE_VISIBILITY
3909        bool owner_before(shared_ptr<_Up> const& __p) const _NOEXCEPT
3910        {return __cntrl_ < __p.__cntrl_;}
3911    template <class _Up>
3912        _LIBCPP_INLINE_VISIBILITY
3913        bool owner_before(weak_ptr<_Up> const& __p) const _NOEXCEPT
3914        {return __cntrl_ < __p.__cntrl_;}
3915    _LIBCPP_INLINE_VISIBILITY
3916    bool
3917    __owner_equivalent(const shared_ptr& __p) const
3918        {return __cntrl_ == __p.__cntrl_;}
3919
3920#ifndef _LIBCPP_NO_RTTI
3921    template <class _Dp>
3922        _LIBCPP_INLINE_VISIBILITY
3923        _Dp* __get_deleter() const _NOEXCEPT
3924            {return static_cast<_Dp*>(__cntrl_
3925                    ? const_cast<void *>(__cntrl_->__get_deleter(typeid(_Dp)))
3926                      : nullptr);}
3927#endif  // _LIBCPP_NO_RTTI
3928
3929    template<class _Yp, class _CntrlBlk>
3930    static shared_ptr<_Tp>
3931    __create_with_control_block(_Yp* __p, _CntrlBlk* __cntrl)
3932    {
3933        shared_ptr<_Tp> __r;
3934        __r.__ptr_ = __p;
3935        __r.__cntrl_ = __cntrl;
3936        __r.__enable_weak_this(__r.__ptr_, __r.__ptr_);
3937        return __r;
3938    }
3939
3940private:
3941    template <class _Yp, bool = is_function<_Yp>::value>
3942        struct __shared_ptr_default_allocator
3943        {
3944            typedef allocator<_Yp> type;
3945        };
3946
3947    template <class _Yp>
3948        struct __shared_ptr_default_allocator<_Yp, true>
3949        {
3950            typedef allocator<__shared_ptr_dummy_rebind_allocator_type> type;
3951        };
3952
3953    template <class _Yp, class _OrigPtr>
3954        _LIBCPP_INLINE_VISIBILITY
3955        typename enable_if<is_convertible<_OrigPtr*,
3956                                          const enable_shared_from_this<_Yp>*
3957        >::value,
3958            void>::type
3959        __enable_weak_this(const enable_shared_from_this<_Yp>* __e,
3960                           _OrigPtr* __ptr) _NOEXCEPT
3961        {
3962            typedef typename remove_cv<_Yp>::type _RawYp;
3963            if (__e && __e->__weak_this_.expired())
3964            {
3965                __e->__weak_this_ = shared_ptr<_RawYp>(*this,
3966                    const_cast<_RawYp*>(static_cast<const _Yp*>(__ptr)));
3967            }
3968        }
3969
3970    _LIBCPP_INLINE_VISIBILITY void __enable_weak_this(...) _NOEXCEPT {}
3971
3972    template <class _Up> friend class _LIBCPP_TEMPLATE_VIS shared_ptr;
3973    template <class _Up> friend class _LIBCPP_TEMPLATE_VIS weak_ptr;
3974};
3975
3976#ifndef _LIBCPP_HAS_NO_DEDUCTION_GUIDES
3977template<class _Tp>
3978shared_ptr(weak_ptr<_Tp>) -> shared_ptr<_Tp>;
3979template<class _Tp, class _Dp>
3980shared_ptr(unique_ptr<_Tp, _Dp>) -> shared_ptr<_Tp>;
3981#endif
3982
3983template<class _Tp>
3984inline
3985_LIBCPP_CONSTEXPR
3986shared_ptr<_Tp>::shared_ptr() _NOEXCEPT
3987    : __ptr_(0),
3988      __cntrl_(0)
3989{
3990}
3991
3992template<class _Tp>
3993inline
3994_LIBCPP_CONSTEXPR
3995shared_ptr<_Tp>::shared_ptr(nullptr_t) _NOEXCEPT
3996    : __ptr_(0),
3997      __cntrl_(0)
3998{
3999}
4000
4001template<class _Tp>
4002template<class _Yp>
4003shared_ptr<_Tp>::shared_ptr(_Yp* __p,
4004                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4005    : __ptr_(__p)
4006{
4007    unique_ptr<_Yp> __hold(__p);
4008    typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
4009    typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, _AllocT > _CntrlBlk;
4010    __cntrl_ = new _CntrlBlk(__p, default_delete<_Yp>(), _AllocT());
4011    __hold.release();
4012    __enable_weak_this(__p, __p);
4013}
4014
4015template<class _Tp>
4016template<class _Yp, class _Dp>
4017shared_ptr<_Tp>::shared_ptr(_Yp* __p, _Dp __d,
4018                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4019    : __ptr_(__p)
4020{
4021#ifndef _LIBCPP_NO_EXCEPTIONS
4022    try
4023    {
4024#endif  // _LIBCPP_NO_EXCEPTIONS
4025        typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
4026        typedef __shared_ptr_pointer<_Yp*, _Dp, _AllocT > _CntrlBlk;
4027        __cntrl_ = new _CntrlBlk(__p, __d, _AllocT());
4028        __enable_weak_this(__p, __p);
4029#ifndef _LIBCPP_NO_EXCEPTIONS
4030    }
4031    catch (...)
4032    {
4033        __d(__p);
4034        throw;
4035    }
4036#endif  // _LIBCPP_NO_EXCEPTIONS
4037}
4038
4039template<class _Tp>
4040template<class _Dp>
4041shared_ptr<_Tp>::shared_ptr(nullptr_t __p, _Dp __d)
4042    : __ptr_(0)
4043{
4044#ifndef _LIBCPP_NO_EXCEPTIONS
4045    try
4046    {
4047#endif  // _LIBCPP_NO_EXCEPTIONS
4048        typedef typename __shared_ptr_default_allocator<_Tp>::type _AllocT;
4049        typedef __shared_ptr_pointer<nullptr_t, _Dp, _AllocT > _CntrlBlk;
4050        __cntrl_ = new _CntrlBlk(__p, __d, _AllocT());
4051#ifndef _LIBCPP_NO_EXCEPTIONS
4052    }
4053    catch (...)
4054    {
4055        __d(__p);
4056        throw;
4057    }
4058#endif  // _LIBCPP_NO_EXCEPTIONS
4059}
4060
4061template<class _Tp>
4062template<class _Yp, class _Dp, class _Alloc>
4063shared_ptr<_Tp>::shared_ptr(_Yp* __p, _Dp __d, _Alloc __a,
4064                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4065    : __ptr_(__p)
4066{
4067#ifndef _LIBCPP_NO_EXCEPTIONS
4068    try
4069    {
4070#endif  // _LIBCPP_NO_EXCEPTIONS
4071        typedef __shared_ptr_pointer<_Yp*, _Dp, _Alloc> _CntrlBlk;
4072        typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4073        typedef __allocator_destructor<_A2> _D2;
4074        _A2 __a2(__a);
4075        unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4076        ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4077            _CntrlBlk(__p, __d, __a);
4078        __cntrl_ = _VSTD::addressof(*__hold2.release());
4079        __enable_weak_this(__p, __p);
4080#ifndef _LIBCPP_NO_EXCEPTIONS
4081    }
4082    catch (...)
4083    {
4084        __d(__p);
4085        throw;
4086    }
4087#endif  // _LIBCPP_NO_EXCEPTIONS
4088}
4089
4090template<class _Tp>
4091template<class _Dp, class _Alloc>
4092shared_ptr<_Tp>::shared_ptr(nullptr_t __p, _Dp __d, _Alloc __a)
4093    : __ptr_(0)
4094{
4095#ifndef _LIBCPP_NO_EXCEPTIONS
4096    try
4097    {
4098#endif  // _LIBCPP_NO_EXCEPTIONS
4099        typedef __shared_ptr_pointer<nullptr_t, _Dp, _Alloc> _CntrlBlk;
4100        typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4101        typedef __allocator_destructor<_A2> _D2;
4102        _A2 __a2(__a);
4103        unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4104        ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4105            _CntrlBlk(__p, __d, __a);
4106        __cntrl_ = _VSTD::addressof(*__hold2.release());
4107#ifndef _LIBCPP_NO_EXCEPTIONS
4108    }
4109    catch (...)
4110    {
4111        __d(__p);
4112        throw;
4113    }
4114#endif  // _LIBCPP_NO_EXCEPTIONS
4115}
4116
4117template<class _Tp>
4118template<class _Yp>
4119inline
4120shared_ptr<_Tp>::shared_ptr(const shared_ptr<_Yp>& __r, element_type *__p) _NOEXCEPT
4121    : __ptr_(__p),
4122      __cntrl_(__r.__cntrl_)
4123{
4124    if (__cntrl_)
4125        __cntrl_->__add_shared();
4126}
4127
4128template<class _Tp>
4129inline
4130shared_ptr<_Tp>::shared_ptr(const shared_ptr& __r) _NOEXCEPT
4131    : __ptr_(__r.__ptr_),
4132      __cntrl_(__r.__cntrl_)
4133{
4134    if (__cntrl_)
4135        __cntrl_->__add_shared();
4136}
4137
4138template<class _Tp>
4139template<class _Yp>
4140inline
4141shared_ptr<_Tp>::shared_ptr(const shared_ptr<_Yp>& __r,
4142                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4143         _NOEXCEPT
4144    : __ptr_(__r.__ptr_),
4145      __cntrl_(__r.__cntrl_)
4146{
4147    if (__cntrl_)
4148        __cntrl_->__add_shared();
4149}
4150
4151#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4152
4153template<class _Tp>
4154inline
4155shared_ptr<_Tp>::shared_ptr(shared_ptr&& __r) _NOEXCEPT
4156    : __ptr_(__r.__ptr_),
4157      __cntrl_(__r.__cntrl_)
4158{
4159    __r.__ptr_ = 0;
4160    __r.__cntrl_ = 0;
4161}
4162
4163template<class _Tp>
4164template<class _Yp>
4165inline
4166shared_ptr<_Tp>::shared_ptr(shared_ptr<_Yp>&& __r,
4167                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4168         _NOEXCEPT
4169    : __ptr_(__r.__ptr_),
4170      __cntrl_(__r.__cntrl_)
4171{
4172    __r.__ptr_ = 0;
4173    __r.__cntrl_ = 0;
4174}
4175
4176#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4177
4178#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
4179template<class _Tp>
4180template<class _Yp>
4181#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4182shared_ptr<_Tp>::shared_ptr(auto_ptr<_Yp>&& __r,
4183#else
4184shared_ptr<_Tp>::shared_ptr(auto_ptr<_Yp> __r,
4185#endif
4186                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4187    : __ptr_(__r.get())
4188{
4189    typedef __shared_ptr_pointer<_Yp*, default_delete<_Yp>, allocator<_Yp> > _CntrlBlk;
4190    __cntrl_ = new _CntrlBlk(__r.get(), default_delete<_Yp>(), allocator<_Yp>());
4191    __enable_weak_this(__r.get(), __r.get());
4192    __r.release();
4193}
4194#endif
4195
4196template<class _Tp>
4197template <class _Yp, class _Dp>
4198#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4199shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
4200#else
4201shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
4202#endif
4203                            typename enable_if
4204                            <
4205                                !is_lvalue_reference<_Dp>::value &&
4206                                !is_array<_Yp>::value &&
4207                                is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4208                                __nat
4209                            >::type)
4210    : __ptr_(__r.get())
4211{
4212#if _LIBCPP_STD_VER > 11
4213    if (__ptr_ == nullptr)
4214        __cntrl_ = nullptr;
4215    else
4216#endif
4217    {
4218        typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
4219        typedef __shared_ptr_pointer<_Yp*, _Dp, _AllocT > _CntrlBlk;
4220        __cntrl_ = new _CntrlBlk(__r.get(), __r.get_deleter(), _AllocT());
4221        __enable_weak_this(__r.get(), __r.get());
4222    }
4223    __r.release();
4224}
4225
4226template<class _Tp>
4227template <class _Yp, class _Dp>
4228#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4229shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp>&& __r,
4230#else
4231shared_ptr<_Tp>::shared_ptr(unique_ptr<_Yp, _Dp> __r,
4232#endif
4233                            typename enable_if
4234                            <
4235                                is_lvalue_reference<_Dp>::value &&
4236                                !is_array<_Yp>::value &&
4237                                is_convertible<typename unique_ptr<_Yp, _Dp>::pointer, element_type*>::value,
4238                                __nat
4239                            >::type)
4240    : __ptr_(__r.get())
4241{
4242#if _LIBCPP_STD_VER > 11
4243    if (__ptr_ == nullptr)
4244        __cntrl_ = nullptr;
4245    else
4246#endif
4247    {
4248        typedef typename __shared_ptr_default_allocator<_Yp>::type _AllocT;
4249        typedef __shared_ptr_pointer<_Yp*,
4250                                     reference_wrapper<typename remove_reference<_Dp>::type>,
4251                                     _AllocT > _CntrlBlk;
4252        __cntrl_ = new _CntrlBlk(__r.get(), _VSTD::ref(__r.get_deleter()), _AllocT());
4253        __enable_weak_this(__r.get(), __r.get());
4254    }
4255    __r.release();
4256}
4257
4258template<class _Tp>
4259shared_ptr<_Tp>::~shared_ptr()
4260{
4261    if (__cntrl_)
4262        __cntrl_->__release_shared();
4263}
4264
4265template<class _Tp>
4266inline
4267shared_ptr<_Tp>&
4268shared_ptr<_Tp>::operator=(const shared_ptr& __r) _NOEXCEPT
4269{
4270    shared_ptr(__r).swap(*this);
4271    return *this;
4272}
4273
4274template<class _Tp>
4275template<class _Yp>
4276inline
4277typename enable_if
4278<
4279    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4280    shared_ptr<_Tp>&
4281>::type
4282shared_ptr<_Tp>::operator=(const shared_ptr<_Yp>& __r) _NOEXCEPT
4283{
4284    shared_ptr(__r).swap(*this);
4285    return *this;
4286}
4287
4288#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4289
4290template<class _Tp>
4291inline
4292shared_ptr<_Tp>&
4293shared_ptr<_Tp>::operator=(shared_ptr&& __r) _NOEXCEPT
4294{
4295    shared_ptr(_VSTD::move(__r)).swap(*this);
4296    return *this;
4297}
4298
4299template<class _Tp>
4300template<class _Yp>
4301inline
4302typename enable_if
4303<
4304    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4305    shared_ptr<_Tp>&
4306>::type
4307shared_ptr<_Tp>::operator=(shared_ptr<_Yp>&& __r)
4308{
4309    shared_ptr(_VSTD::move(__r)).swap(*this);
4310    return *this;
4311}
4312
4313#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
4314template<class _Tp>
4315template<class _Yp>
4316inline
4317typename enable_if
4318<
4319    !is_array<_Yp>::value &&
4320    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4321    shared_ptr<_Tp>
4322>::type&
4323shared_ptr<_Tp>::operator=(auto_ptr<_Yp>&& __r)
4324{
4325    shared_ptr(_VSTD::move(__r)).swap(*this);
4326    return *this;
4327}
4328#endif
4329
4330template<class _Tp>
4331template <class _Yp, class _Dp>
4332inline
4333typename enable_if
4334<
4335    !is_array<_Yp>::value &&
4336    is_convertible<typename unique_ptr<_Yp, _Dp>::pointer,
4337                   typename shared_ptr<_Tp>::element_type*>::value,
4338    shared_ptr<_Tp>&
4339>::type
4340shared_ptr<_Tp>::operator=(unique_ptr<_Yp, _Dp>&& __r)
4341{
4342    shared_ptr(_VSTD::move(__r)).swap(*this);
4343    return *this;
4344}
4345
4346#else  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4347
4348#if _LIBCPP_STD_VER <= 14 || defined(_LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR)
4349template<class _Tp>
4350template<class _Yp>
4351inline _LIBCPP_INLINE_VISIBILITY
4352typename enable_if
4353<
4354    !is_array<_Yp>::value &&
4355    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4356    shared_ptr<_Tp>&
4357>::type
4358shared_ptr<_Tp>::operator=(auto_ptr<_Yp> __r)
4359{
4360    shared_ptr(__r).swap(*this);
4361    return *this;
4362}
4363#endif
4364
4365template<class _Tp>
4366template <class _Yp, class _Dp>
4367inline _LIBCPP_INLINE_VISIBILITY
4368typename enable_if
4369<
4370    !is_array<_Yp>::value &&
4371    is_convertible<typename unique_ptr<_Yp, _Dp>::pointer,
4372                   typename shared_ptr<_Tp>::element_type*>::value,
4373    shared_ptr<_Tp>&
4374>::type
4375shared_ptr<_Tp>::operator=(unique_ptr<_Yp, _Dp> __r)
4376{
4377    shared_ptr(_VSTD::move(__r)).swap(*this);
4378    return *this;
4379}
4380
4381#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4382
4383template<class _Tp>
4384inline
4385void
4386shared_ptr<_Tp>::swap(shared_ptr& __r) _NOEXCEPT
4387{
4388    _VSTD::swap(__ptr_, __r.__ptr_);
4389    _VSTD::swap(__cntrl_, __r.__cntrl_);
4390}
4391
4392template<class _Tp>
4393inline
4394void
4395shared_ptr<_Tp>::reset() _NOEXCEPT
4396{
4397    shared_ptr().swap(*this);
4398}
4399
4400template<class _Tp>
4401template<class _Yp>
4402inline
4403typename enable_if
4404<
4405    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4406    void
4407>::type
4408shared_ptr<_Tp>::reset(_Yp* __p)
4409{
4410    shared_ptr(__p).swap(*this);
4411}
4412
4413template<class _Tp>
4414template<class _Yp, class _Dp>
4415inline
4416typename enable_if
4417<
4418    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4419    void
4420>::type
4421shared_ptr<_Tp>::reset(_Yp* __p, _Dp __d)
4422{
4423    shared_ptr(__p, __d).swap(*this);
4424}
4425
4426template<class _Tp>
4427template<class _Yp, class _Dp, class _Alloc>
4428inline
4429typename enable_if
4430<
4431    is_convertible<_Yp*, typename shared_ptr<_Tp>::element_type*>::value,
4432    void
4433>::type
4434shared_ptr<_Tp>::reset(_Yp* __p, _Dp __d, _Alloc __a)
4435{
4436    shared_ptr(__p, __d, __a).swap(*this);
4437}
4438
4439template<class _Tp, class ..._Args>
4440inline _LIBCPP_INLINE_VISIBILITY
4441typename enable_if
4442<
4443    !is_array<_Tp>::value,
4444    shared_ptr<_Tp>
4445>::type
4446make_shared(_Args&& ...__args)
4447{
4448    static_assert(is_constructible<_Tp, _Args...>::value, "Can't construct object in make_shared");
4449    typedef __shared_ptr_emplace<_Tp, allocator<_Tp> > _CntrlBlk;
4450    typedef allocator<_CntrlBlk> _A2;
4451    typedef __allocator_destructor<_A2> _D2;
4452
4453    _A2 __a2;
4454    unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4455    ::new(__hold2.get()) _CntrlBlk(__a2, _VSTD::forward<_Args>(__args)...);
4456
4457    _Tp *__ptr = __hold2.get()->get();
4458    return shared_ptr<_Tp>::__create_with_control_block(__ptr, __hold2.release());
4459}
4460
4461template<class _Tp, class _Alloc, class ..._Args>
4462inline _LIBCPP_INLINE_VISIBILITY
4463typename enable_if
4464<
4465    !is_array<_Tp>::value,
4466    shared_ptr<_Tp>
4467>::type
4468allocate_shared(const _Alloc& __a, _Args&& ...__args)
4469{
4470    static_assert( is_constructible<_Tp, _Args...>::value, "Can't construct object in allocate_shared");
4471
4472    typedef __shared_ptr_emplace<_Tp, _Alloc> _CntrlBlk;
4473    typedef typename __allocator_traits_rebind<_Alloc, _CntrlBlk>::type _A2;
4474    typedef __allocator_destructor<_A2> _D2;
4475
4476    _A2 __a2(__a);
4477    unique_ptr<_CntrlBlk, _D2> __hold2(__a2.allocate(1), _D2(__a2, 1));
4478    ::new(static_cast<void*>(_VSTD::addressof(*__hold2.get())))
4479        _CntrlBlk(__a, _VSTD::forward<_Args>(__args)...);
4480
4481    typename shared_ptr<_Tp>::element_type *__p = __hold2.get()->get();
4482    return shared_ptr<_Tp>::__create_with_control_block(__p, _VSTD::addressof(*__hold2.release()));
4483}
4484
4485template<class _Tp, class _Up>
4486inline _LIBCPP_INLINE_VISIBILITY
4487bool
4488operator==(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4489{
4490    return __x.get() == __y.get();
4491}
4492
4493template<class _Tp, class _Up>
4494inline _LIBCPP_INLINE_VISIBILITY
4495bool
4496operator!=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4497{
4498    return !(__x == __y);
4499}
4500
4501template<class _Tp, class _Up>
4502inline _LIBCPP_INLINE_VISIBILITY
4503bool
4504operator<(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4505{
4506#if _LIBCPP_STD_VER <= 11
4507    typedef typename common_type<_Tp*, _Up*>::type _Vp;
4508    return less<_Vp>()(__x.get(), __y.get());
4509#else
4510    return less<>()(__x.get(), __y.get());
4511#endif
4512
4513}
4514
4515template<class _Tp, class _Up>
4516inline _LIBCPP_INLINE_VISIBILITY
4517bool
4518operator>(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4519{
4520    return __y < __x;
4521}
4522
4523template<class _Tp, class _Up>
4524inline _LIBCPP_INLINE_VISIBILITY
4525bool
4526operator<=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4527{
4528    return !(__y < __x);
4529}
4530
4531template<class _Tp, class _Up>
4532inline _LIBCPP_INLINE_VISIBILITY
4533bool
4534operator>=(const shared_ptr<_Tp>& __x, const shared_ptr<_Up>& __y) _NOEXCEPT
4535{
4536    return !(__x < __y);
4537}
4538
4539template<class _Tp>
4540inline _LIBCPP_INLINE_VISIBILITY
4541bool
4542operator==(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4543{
4544    return !__x;
4545}
4546
4547template<class _Tp>
4548inline _LIBCPP_INLINE_VISIBILITY
4549bool
4550operator==(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4551{
4552    return !__x;
4553}
4554
4555template<class _Tp>
4556inline _LIBCPP_INLINE_VISIBILITY
4557bool
4558operator!=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4559{
4560    return static_cast<bool>(__x);
4561}
4562
4563template<class _Tp>
4564inline _LIBCPP_INLINE_VISIBILITY
4565bool
4566operator!=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4567{
4568    return static_cast<bool>(__x);
4569}
4570
4571template<class _Tp>
4572inline _LIBCPP_INLINE_VISIBILITY
4573bool
4574operator<(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4575{
4576    return less<_Tp*>()(__x.get(), nullptr);
4577}
4578
4579template<class _Tp>
4580inline _LIBCPP_INLINE_VISIBILITY
4581bool
4582operator<(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4583{
4584    return less<_Tp*>()(nullptr, __x.get());
4585}
4586
4587template<class _Tp>
4588inline _LIBCPP_INLINE_VISIBILITY
4589bool
4590operator>(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4591{
4592    return nullptr < __x;
4593}
4594
4595template<class _Tp>
4596inline _LIBCPP_INLINE_VISIBILITY
4597bool
4598operator>(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4599{
4600    return __x < nullptr;
4601}
4602
4603template<class _Tp>
4604inline _LIBCPP_INLINE_VISIBILITY
4605bool
4606operator<=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4607{
4608    return !(nullptr < __x);
4609}
4610
4611template<class _Tp>
4612inline _LIBCPP_INLINE_VISIBILITY
4613bool
4614operator<=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4615{
4616    return !(__x < nullptr);
4617}
4618
4619template<class _Tp>
4620inline _LIBCPP_INLINE_VISIBILITY
4621bool
4622operator>=(const shared_ptr<_Tp>& __x, nullptr_t) _NOEXCEPT
4623{
4624    return !(__x < nullptr);
4625}
4626
4627template<class _Tp>
4628inline _LIBCPP_INLINE_VISIBILITY
4629bool
4630operator>=(nullptr_t, const shared_ptr<_Tp>& __x) _NOEXCEPT
4631{
4632    return !(nullptr < __x);
4633}
4634
4635template<class _Tp>
4636inline _LIBCPP_INLINE_VISIBILITY
4637void
4638swap(shared_ptr<_Tp>& __x, shared_ptr<_Tp>& __y) _NOEXCEPT
4639{
4640    __x.swap(__y);
4641}
4642
4643template<class _Tp, class _Up>
4644inline _LIBCPP_INLINE_VISIBILITY
4645typename enable_if
4646<
4647    !is_array<_Tp>::value && !is_array<_Up>::value,
4648    shared_ptr<_Tp>
4649>::type
4650static_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
4651{
4652    return shared_ptr<_Tp>(__r, static_cast<_Tp*>(__r.get()));
4653}
4654
4655template<class _Tp, class _Up>
4656inline _LIBCPP_INLINE_VISIBILITY
4657typename enable_if
4658<
4659    !is_array<_Tp>::value && !is_array<_Up>::value,
4660    shared_ptr<_Tp>
4661>::type
4662dynamic_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
4663{
4664    _Tp* __p = dynamic_cast<_Tp*>(__r.get());
4665    return __p ? shared_ptr<_Tp>(__r, __p) : shared_ptr<_Tp>();
4666}
4667
4668template<class _Tp, class _Up>
4669typename enable_if
4670<
4671    is_array<_Tp>::value == is_array<_Up>::value,
4672    shared_ptr<_Tp>
4673>::type
4674const_pointer_cast(const shared_ptr<_Up>& __r) _NOEXCEPT
4675{
4676    typedef typename remove_extent<_Tp>::type _RTp;
4677    return shared_ptr<_Tp>(__r, const_cast<_RTp*>(__r.get()));
4678}
4679
4680#ifndef _LIBCPP_NO_RTTI
4681
4682template<class _Dp, class _Tp>
4683inline _LIBCPP_INLINE_VISIBILITY
4684_Dp*
4685get_deleter(const shared_ptr<_Tp>& __p) _NOEXCEPT
4686{
4687    return __p.template __get_deleter<_Dp>();
4688}
4689
4690#endif  // _LIBCPP_NO_RTTI
4691
4692template<class _Tp>
4693class _LIBCPP_TEMPLATE_VIS weak_ptr
4694{
4695public:
4696    typedef _Tp element_type;
4697private:
4698    element_type*        __ptr_;
4699    __shared_weak_count* __cntrl_;
4700
4701public:
4702    _LIBCPP_INLINE_VISIBILITY
4703    _LIBCPP_CONSTEXPR weak_ptr() _NOEXCEPT;
4704    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(shared_ptr<_Yp> const& __r,
4705                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
4706                        _NOEXCEPT;
4707    _LIBCPP_INLINE_VISIBILITY
4708    weak_ptr(weak_ptr const& __r) _NOEXCEPT;
4709    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(weak_ptr<_Yp> const& __r,
4710                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
4711                         _NOEXCEPT;
4712
4713#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4714    _LIBCPP_INLINE_VISIBILITY
4715    weak_ptr(weak_ptr&& __r) _NOEXCEPT;
4716    template<class _Yp> _LIBCPP_INLINE_VISIBILITY weak_ptr(weak_ptr<_Yp>&& __r,
4717                   typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type = 0)
4718                         _NOEXCEPT;
4719#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4720    ~weak_ptr();
4721
4722    _LIBCPP_INLINE_VISIBILITY
4723    weak_ptr& operator=(weak_ptr const& __r) _NOEXCEPT;
4724    template<class _Yp>
4725        typename enable_if
4726        <
4727            is_convertible<_Yp*, element_type*>::value,
4728            weak_ptr&
4729        >::type
4730        _LIBCPP_INLINE_VISIBILITY
4731        operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT;
4732
4733#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4734
4735    _LIBCPP_INLINE_VISIBILITY
4736    weak_ptr& operator=(weak_ptr&& __r) _NOEXCEPT;
4737    template<class _Yp>
4738        typename enable_if
4739        <
4740            is_convertible<_Yp*, element_type*>::value,
4741            weak_ptr&
4742        >::type
4743        _LIBCPP_INLINE_VISIBILITY
4744        operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT;
4745
4746#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4747
4748    template<class _Yp>
4749        typename enable_if
4750        <
4751            is_convertible<_Yp*, element_type*>::value,
4752            weak_ptr&
4753        >::type
4754        _LIBCPP_INLINE_VISIBILITY
4755        operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT;
4756
4757    _LIBCPP_INLINE_VISIBILITY
4758    void swap(weak_ptr& __r) _NOEXCEPT;
4759    _LIBCPP_INLINE_VISIBILITY
4760    void reset() _NOEXCEPT;
4761
4762    _LIBCPP_INLINE_VISIBILITY
4763    long use_count() const _NOEXCEPT
4764        {return __cntrl_ ? __cntrl_->use_count() : 0;}
4765    _LIBCPP_INLINE_VISIBILITY
4766    bool expired() const _NOEXCEPT
4767        {return __cntrl_ == 0 || __cntrl_->use_count() == 0;}
4768    shared_ptr<_Tp> lock() const _NOEXCEPT;
4769    template<class _Up>
4770        _LIBCPP_INLINE_VISIBILITY
4771        bool owner_before(const shared_ptr<_Up>& __r) const _NOEXCEPT
4772        {return __cntrl_ < __r.__cntrl_;}
4773    template<class _Up>
4774        _LIBCPP_INLINE_VISIBILITY
4775        bool owner_before(const weak_ptr<_Up>& __r) const _NOEXCEPT
4776        {return __cntrl_ < __r.__cntrl_;}
4777
4778    template <class _Up> friend class _LIBCPP_TEMPLATE_VIS weak_ptr;
4779    template <class _Up> friend class _LIBCPP_TEMPLATE_VIS shared_ptr;
4780};
4781
4782#ifndef _LIBCPP_HAS_NO_DEDUCTION_GUIDES
4783template<class _Tp>
4784weak_ptr(shared_ptr<_Tp>) -> weak_ptr<_Tp>;
4785#endif
4786
4787template<class _Tp>
4788inline
4789_LIBCPP_CONSTEXPR
4790weak_ptr<_Tp>::weak_ptr() _NOEXCEPT
4791    : __ptr_(0),
4792      __cntrl_(0)
4793{
4794}
4795
4796template<class _Tp>
4797inline
4798weak_ptr<_Tp>::weak_ptr(weak_ptr const& __r) _NOEXCEPT
4799    : __ptr_(__r.__ptr_),
4800      __cntrl_(__r.__cntrl_)
4801{
4802    if (__cntrl_)
4803        __cntrl_->__add_weak();
4804}
4805
4806template<class _Tp>
4807template<class _Yp>
4808inline
4809weak_ptr<_Tp>::weak_ptr(shared_ptr<_Yp> const& __r,
4810                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
4811                         _NOEXCEPT
4812    : __ptr_(__r.__ptr_),
4813      __cntrl_(__r.__cntrl_)
4814{
4815    if (__cntrl_)
4816        __cntrl_->__add_weak();
4817}
4818
4819template<class _Tp>
4820template<class _Yp>
4821inline
4822weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp> const& __r,
4823                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
4824         _NOEXCEPT
4825    : __ptr_(__r.__ptr_),
4826      __cntrl_(__r.__cntrl_)
4827{
4828    if (__cntrl_)
4829        __cntrl_->__add_weak();
4830}
4831
4832#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4833
4834template<class _Tp>
4835inline
4836weak_ptr<_Tp>::weak_ptr(weak_ptr&& __r) _NOEXCEPT
4837    : __ptr_(__r.__ptr_),
4838      __cntrl_(__r.__cntrl_)
4839{
4840    __r.__ptr_ = 0;
4841    __r.__cntrl_ = 0;
4842}
4843
4844template<class _Tp>
4845template<class _Yp>
4846inline
4847weak_ptr<_Tp>::weak_ptr(weak_ptr<_Yp>&& __r,
4848                        typename enable_if<is_convertible<_Yp*, _Tp*>::value, __nat*>::type)
4849         _NOEXCEPT
4850    : __ptr_(__r.__ptr_),
4851      __cntrl_(__r.__cntrl_)
4852{
4853    __r.__ptr_ = 0;
4854    __r.__cntrl_ = 0;
4855}
4856
4857#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4858
4859template<class _Tp>
4860weak_ptr<_Tp>::~weak_ptr()
4861{
4862    if (__cntrl_)
4863        __cntrl_->__release_weak();
4864}
4865
4866template<class _Tp>
4867inline
4868weak_ptr<_Tp>&
4869weak_ptr<_Tp>::operator=(weak_ptr const& __r) _NOEXCEPT
4870{
4871    weak_ptr(__r).swap(*this);
4872    return *this;
4873}
4874
4875template<class _Tp>
4876template<class _Yp>
4877inline
4878typename enable_if
4879<
4880    is_convertible<_Yp*, _Tp*>::value,
4881    weak_ptr<_Tp>&
4882>::type
4883weak_ptr<_Tp>::operator=(weak_ptr<_Yp> const& __r) _NOEXCEPT
4884{
4885    weak_ptr(__r).swap(*this);
4886    return *this;
4887}
4888
4889#ifndef _LIBCPP_HAS_NO_RVALUE_REFERENCES
4890
4891template<class _Tp>
4892inline
4893weak_ptr<_Tp>&
4894weak_ptr<_Tp>::operator=(weak_ptr&& __r) _NOEXCEPT
4895{
4896    weak_ptr(_VSTD::move(__r)).swap(*this);
4897    return *this;
4898}
4899
4900template<class _Tp>
4901template<class _Yp>
4902inline
4903typename enable_if
4904<
4905    is_convertible<_Yp*, _Tp*>::value,
4906    weak_ptr<_Tp>&
4907>::type
4908weak_ptr<_Tp>::operator=(weak_ptr<_Yp>&& __r) _NOEXCEPT
4909{
4910    weak_ptr(_VSTD::move(__r)).swap(*this);
4911    return *this;
4912}
4913
4914#endif  // _LIBCPP_HAS_NO_RVALUE_REFERENCES
4915
4916template<class _Tp>
4917template<class _Yp>
4918inline
4919typename enable_if
4920<
4921    is_convertible<_Yp*, _Tp*>::value,
4922    weak_ptr<_Tp>&
4923>::type
4924weak_ptr<_Tp>::operator=(shared_ptr<_Yp> const& __r) _NOEXCEPT
4925{
4926    weak_ptr(__r).swap(*this);
4927    return *this;
4928}
4929
4930template<class _Tp>
4931inline
4932void
4933weak_ptr<_Tp>::swap(weak_ptr& __r) _NOEXCEPT
4934{
4935    _VSTD::swap(__ptr_, __r.__ptr_);
4936    _VSTD::swap(__cntrl_, __r.__cntrl_);
4937}
4938
4939template<class _Tp>
4940inline _LIBCPP_INLINE_VISIBILITY
4941void
4942swap(weak_ptr<_Tp>& __x, weak_ptr<_Tp>& __y) _NOEXCEPT
4943{
4944    __x.swap(__y);
4945}
4946
4947template<class _Tp>
4948inline
4949void
4950weak_ptr<_Tp>::reset() _NOEXCEPT
4951{
4952    weak_ptr().swap(*this);
4953}
4954
4955template<class _Tp>
4956template<class _Yp>
4957shared_ptr<_Tp>::shared_ptr(const weak_ptr<_Yp>& __r,
4958                            typename enable_if<is_convertible<_Yp*, element_type*>::value, __nat>::type)
4959    : __ptr_(__r.__ptr_),
4960      __cntrl_(__r.__cntrl_ ? __r.__cntrl_->lock() : __r.__cntrl_)
4961{
4962    if (__cntrl_ == 0)
4963        __throw_bad_weak_ptr();
4964}
4965
4966template<class _Tp>
4967shared_ptr<_Tp>
4968weak_ptr<_Tp>::lock() const _NOEXCEPT
4969{
4970    shared_ptr<_Tp> __r;
4971    __r.__cntrl_ = __cntrl_ ? __cntrl_->lock() : __cntrl_;
4972    if (__r.__cntrl_)
4973        __r.__ptr_ = __ptr_;
4974    return __r;
4975}
4976
4977#if _LIBCPP_STD_VER > 14
4978template <class _Tp = void> struct owner_less;
4979#else
4980template <class _Tp> struct owner_less;
4981#endif
4982
4983template <class _Tp>
4984struct _LIBCPP_TEMPLATE_VIS owner_less<shared_ptr<_Tp> >
4985    : binary_function<shared_ptr<_Tp>, shared_ptr<_Tp>, bool>
4986{
4987    typedef bool result_type;
4988    _LIBCPP_INLINE_VISIBILITY
4989    bool operator()(shared_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const _NOEXCEPT
4990        {return __x.owner_before(__y);}
4991    _LIBCPP_INLINE_VISIBILITY
4992    bool operator()(shared_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const _NOEXCEPT
4993        {return __x.owner_before(__y);}
4994    _LIBCPP_INLINE_VISIBILITY
4995    bool operator()(  weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const _NOEXCEPT
4996        {return __x.owner_before(__y);}
4997};
4998
4999template <class _Tp>
5000struct _LIBCPP_TEMPLATE_VIS owner_less<weak_ptr<_Tp> >
5001    : binary_function<weak_ptr<_Tp>, weak_ptr<_Tp>, bool>
5002{
5003    typedef bool result_type;
5004    _LIBCPP_INLINE_VISIBILITY
5005    bool operator()(  weak_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const _NOEXCEPT
5006        {return __x.owner_before(__y);}
5007    _LIBCPP_INLINE_VISIBILITY
5008    bool operator()(shared_ptr<_Tp> const& __x,   weak_ptr<_Tp> const& __y) const _NOEXCEPT
5009        {return __x.owner_before(__y);}
5010    _LIBCPP_INLINE_VISIBILITY
5011    bool operator()(  weak_ptr<_Tp> const& __x, shared_ptr<_Tp> const& __y) const _NOEXCEPT
5012        {return __x.owner_before(__y);}
5013};
5014
5015#if _LIBCPP_STD_VER > 14
5016template <>
5017struct _LIBCPP_TEMPLATE_VIS owner_less<void>
5018{
5019    template <class _Tp, class _Up>
5020    _LIBCPP_INLINE_VISIBILITY
5021    bool operator()( shared_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const _NOEXCEPT
5022        {return __x.owner_before(__y);}
5023    template <class _Tp, class _Up>
5024    _LIBCPP_INLINE_VISIBILITY
5025    bool operator()( shared_ptr<_Tp> const& __x,   weak_ptr<_Up> const& __y) const _NOEXCEPT
5026        {return __x.owner_before(__y);}
5027    template <class _Tp, class _Up>
5028    _LIBCPP_INLINE_VISIBILITY
5029    bool operator()(   weak_ptr<_Tp> const& __x, shared_ptr<_Up> const& __y) const _NOEXCEPT
5030        {return __x.owner_before(__y);}
5031    template <class _Tp, class _Up>
5032    _LIBCPP_INLINE_VISIBILITY
5033    bool operator()(   weak_ptr<_Tp> const& __x,   weak_ptr<_Up> const& __y) const _NOEXCEPT
5034        {return __x.owner_before(__y);}
5035    typedef void is_transparent;
5036};
5037#endif
5038
5039template<class _Tp>
5040class _LIBCPP_TEMPLATE_VIS enable_shared_from_this
5041{
5042    mutable weak_ptr<_Tp> __weak_this_;
5043protected:
5044    _LIBCPP_INLINE_VISIBILITY _LIBCPP_CONSTEXPR
5045    enable_shared_from_this() _NOEXCEPT {}
5046    _LIBCPP_INLINE_VISIBILITY
5047    enable_shared_from_this(enable_shared_from_this const&) _NOEXCEPT {}
5048    _LIBCPP_INLINE_VISIBILITY
5049    enable_shared_from_this& operator=(enable_shared_from_this const&) _NOEXCEPT
5050        {return *this;}
5051    _LIBCPP_INLINE_VISIBILITY
5052    ~enable_shared_from_this() {}
5053public:
5054    _LIBCPP_INLINE_VISIBILITY
5055    shared_ptr<_Tp> shared_from_this()
5056        {return shared_ptr<_Tp>(__weak_this_);}
5057    _LIBCPP_INLINE_VISIBILITY
5058    shared_ptr<_Tp const> shared_from_this() const
5059        {return shared_ptr<const _Tp>(__weak_this_);}
5060
5061#if _LIBCPP_STD_VER > 14
5062    _LIBCPP_INLINE_VISIBILITY
5063    weak_ptr<_Tp> weak_from_this() _NOEXCEPT
5064       { return __weak_this_; }
5065
5066    _LIBCPP_INLINE_VISIBILITY
5067    weak_ptr<const _Tp> weak_from_this() const _NOEXCEPT
5068        { return __weak_this_; }
5069#endif // _LIBCPP_STD_VER > 14
5070
5071    template <class _Up> friend class shared_ptr;
5072};
5073
5074template <class _Tp>
5075struct _LIBCPP_TEMPLATE_VIS hash<shared_ptr<_Tp> >
5076{
5077    typedef shared_ptr<_Tp>      argument_type;
5078    typedef size_t               result_type;
5079
5080    _LIBCPP_INLINE_VISIBILITY
5081    result_type operator()(const argument_type& __ptr) const _NOEXCEPT
5082    {
5083        return hash<_Tp*>()(__ptr.get());
5084    }
5085};
5086
5087template<class _CharT, class _Traits, class _Yp>
5088inline _LIBCPP_INLINE_VISIBILITY
5089basic_ostream<_CharT, _Traits>&
5090operator<<(basic_ostream<_CharT, _Traits>& __os, shared_ptr<_Yp> const& __p);
5091
5092
5093#if !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
5094
5095class _LIBCPP_TYPE_VIS __sp_mut
5096{
5097    void* __lx;
5098public:
5099    void lock() _NOEXCEPT;
5100    void unlock() _NOEXCEPT;
5101
5102private:
5103    _LIBCPP_CONSTEXPR __sp_mut(void*) _NOEXCEPT;
5104    __sp_mut(const __sp_mut&);
5105    __sp_mut& operator=(const __sp_mut&);
5106
5107    friend _LIBCPP_FUNC_VIS __sp_mut& __get_sp_mut(const void*);
5108};
5109
5110_LIBCPP_FUNC_VIS _LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5111__sp_mut& __get_sp_mut(const void*);
5112
5113template <class _Tp>
5114inline _LIBCPP_INLINE_VISIBILITY
5115bool
5116atomic_is_lock_free(const shared_ptr<_Tp>*)
5117{
5118    return false;
5119}
5120
5121template <class _Tp>
5122_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5123shared_ptr<_Tp>
5124atomic_load(const shared_ptr<_Tp>* __p)
5125{
5126    __sp_mut& __m = __get_sp_mut(__p);
5127    __m.lock();
5128    shared_ptr<_Tp> __q = *__p;
5129    __m.unlock();
5130    return __q;
5131}
5132
5133template <class _Tp>
5134inline _LIBCPP_INLINE_VISIBILITY
5135_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5136shared_ptr<_Tp>
5137atomic_load_explicit(const shared_ptr<_Tp>* __p, memory_order)
5138{
5139    return atomic_load(__p);
5140}
5141
5142template <class _Tp>
5143_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5144void
5145atomic_store(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
5146{
5147    __sp_mut& __m = __get_sp_mut(__p);
5148    __m.lock();
5149    __p->swap(__r);
5150    __m.unlock();
5151}
5152
5153template <class _Tp>
5154inline _LIBCPP_INLINE_VISIBILITY
5155_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5156void
5157atomic_store_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
5158{
5159    atomic_store(__p, __r);
5160}
5161
5162template <class _Tp>
5163_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5164shared_ptr<_Tp>
5165atomic_exchange(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r)
5166{
5167    __sp_mut& __m = __get_sp_mut(__p);
5168    __m.lock();
5169    __p->swap(__r);
5170    __m.unlock();
5171    return __r;
5172}
5173
5174template <class _Tp>
5175inline _LIBCPP_INLINE_VISIBILITY
5176_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5177shared_ptr<_Tp>
5178atomic_exchange_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp> __r, memory_order)
5179{
5180    return atomic_exchange(__p, __r);
5181}
5182
5183template <class _Tp>
5184_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5185bool
5186atomic_compare_exchange_strong(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
5187{
5188    shared_ptr<_Tp> __temp;
5189    __sp_mut& __m = __get_sp_mut(__p);
5190    __m.lock();
5191    if (__p->__owner_equivalent(*__v))
5192    {
5193        _VSTD::swap(__temp, *__p);
5194        *__p = __w;
5195        __m.unlock();
5196        return true;
5197    }
5198    _VSTD::swap(__temp, *__v);
5199    *__v = *__p;
5200    __m.unlock();
5201    return false;
5202}
5203
5204template <class _Tp>
5205inline _LIBCPP_INLINE_VISIBILITY
5206_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5207bool
5208atomic_compare_exchange_weak(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v, shared_ptr<_Tp> __w)
5209{
5210    return atomic_compare_exchange_strong(__p, __v, __w);
5211}
5212
5213template <class _Tp>
5214inline _LIBCPP_INLINE_VISIBILITY
5215_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5216bool
5217atomic_compare_exchange_strong_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
5218                                        shared_ptr<_Tp> __w, memory_order, memory_order)
5219{
5220    return atomic_compare_exchange_strong(__p, __v, __w);
5221}
5222
5223template <class _Tp>
5224inline _LIBCPP_INLINE_VISIBILITY
5225_LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
5226bool
5227atomic_compare_exchange_weak_explicit(shared_ptr<_Tp>* __p, shared_ptr<_Tp>* __v,
5228                                      shared_ptr<_Tp> __w, memory_order, memory_order)
5229{
5230    return atomic_compare_exchange_weak(__p, __v, __w);
5231}
5232
5233#endif  // !defined(_LIBCPP_HAS_NO_ATOMIC_HEADER)
5234
5235//enum class
5236#if defined(_LIBCPP_ABI_POINTER_SAFETY_ENUM_TYPE)
5237# ifndef _LIBCPP_CXX03_LANG
5238enum class pointer_safety : unsigned char {
5239  relaxed,
5240  preferred,
5241  strict
5242};
5243# endif
5244#else
5245struct _LIBCPP_TYPE_VIS pointer_safety
5246{
5247    enum __lx
5248    {
5249        relaxed,
5250        preferred,
5251        strict
5252    };
5253
5254    __lx __v_;
5255
5256    _LIBCPP_INLINE_VISIBILITY
5257    pointer_safety() : __v_() {}
5258
5259    _LIBCPP_INLINE_VISIBILITY
5260    pointer_safety(__lx __v) : __v_(__v) {}
5261    _LIBCPP_INLINE_VISIBILITY
5262    operator int() const {return __v_;}
5263};
5264#endif
5265
5266#if !defined(_LIBCPP_ABI_POINTER_SAFETY_ENUM_TYPE) && \
5267    defined(_LIBCPP_BUILDING_LIBRARY)
5268_LIBCPP_FUNC_VIS pointer_safety get_pointer_safety() _NOEXCEPT;
5269#else
5270// This function is only offered in C++03 under ABI v1.
5271# if !defined(_LIBCPP_ABI_POINTER_SAFETY_ENUM_TYPE) || !defined(_LIBCPP_CXX03_LANG)
5272inline _LIBCPP_INLINE_VISIBILITY
5273pointer_safety get_pointer_safety() _NOEXCEPT {
5274  return pointer_safety::relaxed;
5275}
5276# endif
5277#endif
5278
5279
5280_LIBCPP_FUNC_VIS void declare_reachable(void* __p);
5281_LIBCPP_FUNC_VIS void declare_no_pointers(char* __p, size_t __n);
5282_LIBCPP_FUNC_VIS void undeclare_no_pointers(char* __p, size_t __n);
5283_LIBCPP_FUNC_VIS void* __undeclare_reachable(void* __p);
5284
5285template <class _Tp>
5286inline _LIBCPP_INLINE_VISIBILITY
5287_Tp*
5288undeclare_reachable(_Tp* __p)
5289{
5290    return static_cast<_Tp*>(__undeclare_reachable(__p));
5291}
5292
5293_LIBCPP_FUNC_VIS void* align(size_t __align, size_t __sz, void*& __ptr, size_t& __space);
5294
5295// --- Helper for container swap --
5296template <typename _Alloc>
5297inline _LIBCPP_INLINE_VISIBILITY
5298void __swap_allocator(_Alloc & __a1, _Alloc & __a2)
5299#if _LIBCPP_STD_VER >= 14
5300    _NOEXCEPT
5301#else
5302    _NOEXCEPT_(__is_nothrow_swappable<_Alloc>::value)
5303#endif
5304{
5305    __swap_allocator(__a1, __a2,
5306      integral_constant<bool, _VSTD::allocator_traits<_Alloc>::propagate_on_container_swap::value>());
5307}
5308
5309template <typename _Alloc>
5310_LIBCPP_INLINE_VISIBILITY
5311void __swap_allocator(_Alloc & __a1, _Alloc & __a2, true_type)
5312#if _LIBCPP_STD_VER >= 14
5313    _NOEXCEPT
5314#else
5315    _NOEXCEPT_(__is_nothrow_swappable<_Alloc>::value)
5316#endif
5317{
5318    using _VSTD::swap;
5319    swap(__a1, __a2);
5320}
5321
5322template <typename _Alloc>
5323inline _LIBCPP_INLINE_VISIBILITY
5324void __swap_allocator(_Alloc &, _Alloc &, false_type) _NOEXCEPT {}
5325
5326template <typename _Alloc, typename _Traits=allocator_traits<_Alloc> >
5327struct __noexcept_move_assign_container : public integral_constant<bool,
5328    _Traits::propagate_on_container_move_assignment::value
5329#if _LIBCPP_STD_VER > 14
5330        || _Traits::is_always_equal::value
5331#else
5332        && is_nothrow_move_assignable<_Alloc>::value
5333#endif
5334    > {};
5335
5336
5337#ifndef _LIBCPP_HAS_NO_VARIADICS
5338template <class _Tp, class _Alloc>
5339struct __temp_value {
5340    typedef allocator_traits<_Alloc> _Traits;
5341
5342    typename aligned_storage<sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp)>::type __v;
5343    _Alloc &__a;
5344
5345    _Tp *__addr() { return reinterpret_cast<_Tp *>(addressof(__v)); }
5346    _Tp &   get() { return *__addr(); }
5347
5348    template<class... _Args>
5349    _LIBCPP_NO_CFI
5350    __temp_value(_Alloc &__alloc, _Args&& ... __args) : __a(__alloc) {
5351      _Traits::construct(__a, reinterpret_cast<_Tp*>(addressof(__v)),
5352                         _VSTD::forward<_Args>(__args)...);
5353    }
5354
5355    ~__temp_value() { _Traits::destroy(__a, __addr()); }
5356    };
5357#endif
5358
5359template<typename _Alloc, typename = void, typename = void>
5360struct __is_allocator : false_type {};
5361
5362template<typename _Alloc>
5363struct __is_allocator<_Alloc,
5364       typename __void_t<typename _Alloc::value_type>::type,
5365       typename __void_t<decltype(_VSTD::declval<_Alloc&>().allocate(size_t(0)))>::type
5366     >
5367   : true_type {};
5368
5369// __builtin_new_allocator -- A non-templated helper for allocating and
5370// deallocating memory using __builtin_operator_new and
5371// __builtin_operator_delete. It should be used in preference to
5372// `std::allocator<T>` to avoid additional instantiations.
5373struct __builtin_new_allocator {
5374  struct __builtin_new_deleter {
5375    typedef void* pointer_type;
5376
5377    _LIBCPP_CONSTEXPR explicit __builtin_new_deleter(size_t __size, size_t __align)
5378        : __size_(__size), __align_(__align) {}
5379
5380    void operator()(void* p) const _NOEXCEPT {
5381        std::__libcpp_deallocate(p, __size_, __align_);
5382    }
5383
5384   private:
5385    size_t __size_;
5386    size_t __align_;
5387  };
5388
5389  typedef unique_ptr<void, __builtin_new_deleter> __holder_t;
5390
5391  static __holder_t __allocate_bytes(size_t __s, size_t __align) {
5392      return __holder_t(std::__libcpp_allocate(__s, __align),
5393                     __builtin_new_deleter(__s, __align));
5394  }
5395
5396  static void __deallocate_bytes(void* __p, size_t __s,
5397                                 size_t __align) _NOEXCEPT {
5398      std::__libcpp_deallocate(__p, __s, __align);
5399  }
5400
5401  template <class _Tp>
5402  _LIBCPP_NODEBUG _LIBCPP_ALWAYS_INLINE
5403  static __holder_t __allocate_type(size_t __n) {
5404      return __allocate_bytes(__n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp));
5405  }
5406
5407  template <class _Tp>
5408  _LIBCPP_NODEBUG _LIBCPP_ALWAYS_INLINE
5409  static void __deallocate_type(void* __p, size_t __n) _NOEXCEPT {
5410      __deallocate_bytes(__p, __n * sizeof(_Tp), _LIBCPP_ALIGNOF(_Tp));
5411  }
5412};
5413
5414
5415_LIBCPP_END_NAMESPACE_STD
5416
5417_LIBCPP_POP_MACROS
5418
5419#if defined(_LIBCPP_HAS_PARALLEL_ALGORITHMS) && _LIBCPP_STD_VER >= 17
5420#   include <__pstl_memory>
5421#endif
5422
5423#endif  // _LIBCPP_MEMORY
5424